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//===--- SemaExpr.cpp - Semantic Analysis for Expressions -----------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements semantic analysis for expressions.
//
//===----------------------------------------------------------------------===//
#include "TreeTransform.h"
#include "clang/AST/ASTConsumer.h"
#include "clang/AST/ASTContext.h"
#include "clang/AST/ASTLambda.h"
#include "clang/AST/ASTMutationListener.h"
#include "clang/AST/CXXInheritance.h"
#include "clang/AST/DeclObjC.h"
#include "clang/AST/DeclTemplate.h"
#include "clang/AST/EvaluatedExprVisitor.h"
#include "clang/AST/Expr.h"
#include "clang/AST/ExprCXX.h"
#include "clang/AST/ExprObjC.h"
#include "clang/AST/ExprOpenMP.h"
#include "clang/AST/RecursiveASTVisitor.h"
#include "clang/AST/TypeLoc.h"
#include "clang/Basic/PartialDiagnostic.h"
#include "clang/Basic/SourceManager.h"
#include "clang/Basic/TargetInfo.h"
#include "clang/Lex/LiteralSupport.h"
#include "clang/Lex/Preprocessor.h"
#include "clang/Sema/AnalysisBasedWarnings.h"
#include "clang/Sema/DeclSpec.h"
#include "clang/Sema/DelayedDiagnostic.h"
#include "clang/Sema/Designator.h"
#include "clang/Sema/Initialization.h"
#include "clang/Sema/Lookup.h"
#include "clang/Sema/Overload.h"
#include "clang/Sema/ParsedTemplate.h"
#include "clang/Sema/Scope.h"
#include "clang/Sema/ScopeInfo.h"
#include "clang/Sema/SemaFixItUtils.h"
#include "clang/Sema/SemaInternal.h"
#include "clang/Sema/Template.h"
#include "llvm/Support/ConvertUTF.h"
using namespace clang;
using namespace sema;
/// Determine whether the use of this declaration is valid, without
/// emitting diagnostics.
bool Sema::CanUseDecl(NamedDecl *D, bool TreatUnavailableAsInvalid) {
// See if this is an auto-typed variable whose initializer we are parsing.
if (ParsingInitForAutoVars.count(D))
return false;
// See if this is a deleted function.
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
if (FD->isDeleted())
return false;
// If the function has a deduced return type, and we can't deduce it,
// then we can't use it either.
if (getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
DeduceReturnType(FD, SourceLocation(), /*Diagnose*/ false))
return false;
}
// See if this function is unavailable.
if (TreatUnavailableAsInvalid && D->getAvailability() == AR_Unavailable &&
cast<Decl>(CurContext)->getAvailability() != AR_Unavailable)
return false;
return true;
}
static void DiagnoseUnusedOfDecl(Sema &S, NamedDecl *D, SourceLocation Loc) {
// Warn if this is used but marked unused.
if (const auto *A = D->getAttr<UnusedAttr>()) {
// [[maybe_unused]] should not diagnose uses, but __attribute__((unused))
// should diagnose them.
if (A->getSemanticSpelling() != UnusedAttr::CXX11_maybe_unused &&
A->getSemanticSpelling() != UnusedAttr::C2x_maybe_unused) {
const Decl *DC = cast_or_null<Decl>(S.getCurObjCLexicalContext());
if (DC && !DC->hasAttr<UnusedAttr>())
S.Diag(Loc, diag::warn_used_but_marked_unused) << D->getDeclName();
}
}
}
/// Emit a note explaining that this function is deleted.
void Sema::NoteDeletedFunction(FunctionDecl *Decl) {
assert(Decl->isDeleted());
CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Decl);
if (Method && Method->isDeleted() && Method->isDefaulted()) {
// If the method was explicitly defaulted, point at that declaration.
if (!Method->isImplicit())
Diag(Decl->getLocation(), diag::note_implicitly_deleted);
// Try to diagnose why this special member function was implicitly
// deleted. This might fail, if that reason no longer applies.
CXXSpecialMember CSM = getSpecialMember(Method);
if (CSM != CXXInvalid)
ShouldDeleteSpecialMember(Method, CSM, nullptr, /*Diagnose=*/true);
return;
}
auto *Ctor = dyn_cast<CXXConstructorDecl>(Decl);
if (Ctor && Ctor->isInheritingConstructor())
return NoteDeletedInheritingConstructor(Ctor);
Diag(Decl->getLocation(), diag::note_availability_specified_here)
<< Decl << true;
}
/// Determine whether a FunctionDecl was ever declared with an
/// explicit storage class.
static bool hasAnyExplicitStorageClass(const FunctionDecl *D) {
for (auto I : D->redecls()) {
if (I->getStorageClass() != SC_None)
return true;
}
return false;
}
/// Check whether we're in an extern inline function and referring to a
/// variable or function with internal linkage (C11 6.7.4p3).
///
/// This is only a warning because we used to silently accept this code, but
/// in many cases it will not behave correctly. This is not enabled in C++ mode
/// because the restriction language is a bit weaker (C++11 [basic.def.odr]p6)
/// and so while there may still be user mistakes, most of the time we can't
/// prove that there are errors.
static void diagnoseUseOfInternalDeclInInlineFunction(Sema &S,
const NamedDecl *D,
SourceLocation Loc) {
// This is disabled under C++; there are too many ways for this to fire in
// contexts where the warning is a false positive, or where it is technically
// correct but benign.
if (S.getLangOpts().CPlusPlus)
return;
// Check if this is an inlined function or method.
FunctionDecl *Current = S.getCurFunctionDecl();
if (!Current)
return;
if (!Current->isInlined())
return;
if (!Current->isExternallyVisible())
return;
// Check if the decl has internal linkage.
if (D->getFormalLinkage() != InternalLinkage)
return;
// Downgrade from ExtWarn to Extension if
// (1) the supposedly external inline function is in the main file,
// and probably won't be included anywhere else.
// (2) the thing we're referencing is a pure function.
// (3) the thing we're referencing is another inline function.
// This last can give us false negatives, but it's better than warning on
// wrappers for simple C library functions.
const FunctionDecl *UsedFn = dyn_cast<FunctionDecl>(D);
bool DowngradeWarning = S.getSourceManager().isInMainFile(Loc);
if (!DowngradeWarning && UsedFn)
DowngradeWarning = UsedFn->isInlined() || UsedFn->hasAttr<ConstAttr>();
S.Diag(Loc, DowngradeWarning ? diag::ext_internal_in_extern_inline_quiet
: diag::ext_internal_in_extern_inline)
<< /*IsVar=*/!UsedFn << D;
S.MaybeSuggestAddingStaticToDecl(Current);
S.Diag(D->getCanonicalDecl()->getLocation(), diag::note_entity_declared_at)
<< D;
}
void Sema::MaybeSuggestAddingStaticToDecl(const FunctionDecl *Cur) {
const FunctionDecl *First = Cur->getFirstDecl();
// Suggest "static" on the function, if possible.
if (!hasAnyExplicitStorageClass(First)) {
SourceLocation DeclBegin = First->getSourceRange().getBegin();
Diag(DeclBegin, diag::note_convert_inline_to_static)
<< Cur << FixItHint::CreateInsertion(DeclBegin, "static ");
}
}
/// Determine whether the use of this declaration is valid, and
/// emit any corresponding diagnostics.
///
/// This routine diagnoses various problems with referencing
/// declarations that can occur when using a declaration. For example,
/// it might warn if a deprecated or unavailable declaration is being
/// used, or produce an error (and return true) if a C++0x deleted
/// function is being used.
///
/// \returns true if there was an error (this declaration cannot be
/// referenced), false otherwise.
///
bool Sema::DiagnoseUseOfDecl(NamedDecl *D, ArrayRef<SourceLocation> Locs,
const ObjCInterfaceDecl *UnknownObjCClass,
bool ObjCPropertyAccess,
bool AvoidPartialAvailabilityChecks) {
SourceLocation Loc = Locs.front();
if (getLangOpts().CPlusPlus && isa<FunctionDecl>(D)) {
// If there were any diagnostics suppressed by template argument deduction,
// emit them now.
auto Pos = SuppressedDiagnostics.find(D->getCanonicalDecl());
if (Pos != SuppressedDiagnostics.end()) {
for (const PartialDiagnosticAt &Suppressed : Pos->second)
Diag(Suppressed.first, Suppressed.second);
// Clear out the list of suppressed diagnostics, so that we don't emit
// them again for this specialization. However, we don't obsolete this
// entry from the table, because we want to avoid ever emitting these
// diagnostics again.
Pos->second.clear();
}
// C++ [basic.start.main]p3:
// The function 'main' shall not be used within a program.
if (cast<FunctionDecl>(D)->isMain())
Diag(Loc, diag::ext_main_used);
}
// See if this is an auto-typed variable whose initializer we are parsing.
if (ParsingInitForAutoVars.count(D)) {
if (isa<BindingDecl>(D)) {
Diag(Loc, diag::err_binding_cannot_appear_in_own_initializer)
<< D->getDeclName();
} else {
Diag(Loc, diag::err_auto_variable_cannot_appear_in_own_initializer)
<< D->getDeclName() << cast<VarDecl>(D)->getType();
}
return true;
}
// See if this is a deleted function.
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
if (FD->isDeleted()) {
auto *Ctor = dyn_cast<CXXConstructorDecl>(FD);
if (Ctor && Ctor->isInheritingConstructor())
Diag(Loc, diag::err_deleted_inherited_ctor_use)
<< Ctor->getParent()
<< Ctor->getInheritedConstructor().getConstructor()->getParent();
else
Diag(Loc, diag::err_deleted_function_use);
NoteDeletedFunction(FD);
return true;
}
// If the function has a deduced return type, and we can't deduce it,
// then we can't use it either.
if (getLangOpts().CPlusPlus14 && FD->getReturnType()->isUndeducedType() &&
DeduceReturnType(FD, Loc))
return true;
if (getLangOpts().CUDA && !CheckCUDACall(Loc, FD))
return true;
}
auto getReferencedObjCProp = [](const NamedDecl *D) ->
const ObjCPropertyDecl * {
if (const auto *MD = dyn_cast<ObjCMethodDecl>(D))
return MD->findPropertyDecl();
return nullptr;
};
if (const ObjCPropertyDecl *ObjCPDecl = getReferencedObjCProp(D)) {
if (diagnoseArgIndependentDiagnoseIfAttrs(ObjCPDecl, Loc))
return true;
} else if (diagnoseArgIndependentDiagnoseIfAttrs(D, Loc)) {
return true;
}
// [OpenMP 4.0], 2.15 declare reduction Directive, Restrictions
// Only the variables omp_in and omp_out are allowed in the combiner.
// Only the variables omp_priv and omp_orig are allowed in the
// initializer-clause.
auto *DRD = dyn_cast<OMPDeclareReductionDecl>(CurContext);
if (LangOpts.OpenMP && DRD && !CurContext->containsDecl(D) &&
isa<VarDecl>(D)) {
Diag(Loc, diag::err_omp_wrong_var_in_declare_reduction)
<< getCurFunction()->HasOMPDeclareReductionCombiner;
Diag(D->getLocation(), diag::note_entity_declared_at) << D;
return true;
}
DiagnoseAvailabilityOfDecl(D, Locs, UnknownObjCClass, ObjCPropertyAccess,
AvoidPartialAvailabilityChecks);
DiagnoseUnusedOfDecl(*this, D, Loc);
diagnoseUseOfInternalDeclInInlineFunction(*this, D, Loc);
return false;
}
/// Retrieve the message suffix that should be added to a
/// diagnostic complaining about the given function being deleted or
/// unavailable.
std::string Sema::getDeletedOrUnavailableSuffix(const FunctionDecl *FD) {
std::string Message;
if (FD->getAvailability(&Message))
return ": " + Message;
return std::string();
}
/// DiagnoseSentinelCalls - This routine checks whether a call or
/// message-send is to a declaration with the sentinel attribute, and
/// if so, it checks that the requirements of the sentinel are
/// satisfied.
void Sema::DiagnoseSentinelCalls(NamedDecl *D, SourceLocation Loc,
ArrayRef<Expr *> Args) {
const SentinelAttr *attr = D->getAttr<SentinelAttr>();
if (!attr)
return;
// The number of formal parameters of the declaration.
unsigned numFormalParams;
// The kind of declaration. This is also an index into a %select in
// the diagnostic.
enum CalleeType { CT_Function, CT_Method, CT_Block } calleeType;
if (ObjCMethodDecl *MD = dyn_cast<ObjCMethodDecl>(D)) {
numFormalParams = MD->param_size();
calleeType = CT_Method;
} else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
numFormalParams = FD->param_size();
calleeType = CT_Function;
} else if (isa<VarDecl>(D)) {
QualType type = cast<ValueDecl>(D)->getType();
const FunctionType *fn = nullptr;
if (const PointerType *ptr = type->getAs<PointerType>()) {
fn = ptr->getPointeeType()->getAs<FunctionType>();
if (!fn) return;
calleeType = CT_Function;
} else if (const BlockPointerType *ptr = type->getAs<BlockPointerType>()) {
fn = ptr->getPointeeType()->castAs<FunctionType>();
calleeType = CT_Block;
} else {
return;
}
if (const FunctionProtoType *proto = dyn_cast<FunctionProtoType>(fn)) {
numFormalParams = proto->getNumParams();
} else {
numFormalParams = 0;
}
} else {
return;
}
// "nullPos" is the number of formal parameters at the end which
// effectively count as part of the variadic arguments. This is
// useful if you would prefer to not have *any* formal parameters,
// but the language forces you to have at least one.
unsigned nullPos = attr->getNullPos();
assert((nullPos == 0 || nullPos == 1) && "invalid null position on sentinel");
numFormalParams = (nullPos > numFormalParams ? 0 : numFormalParams - nullPos);
// The number of arguments which should follow the sentinel.
unsigned numArgsAfterSentinel = attr->getSentinel();
// If there aren't enough arguments for all the formal parameters,
// the sentinel, and the args after the sentinel, complain.
if (Args.size() < numFormalParams + numArgsAfterSentinel + 1) {
Diag(Loc, diag::warn_not_enough_argument) << D->getDeclName();
Diag(D->getLocation(), diag::note_sentinel_here) << int(calleeType);
return;
}
// Otherwise, find the sentinel expression.
Expr *sentinelExpr = Args[Args.size() - numArgsAfterSentinel - 1];
if (!sentinelExpr) return;
if (sentinelExpr->isValueDependent()) return;
if (Context.isSentinelNullExpr(sentinelExpr)) return;
// Pick a reasonable string to insert. Optimistically use 'nil', 'nullptr',
// or 'NULL' if those are actually defined in the context. Only use
// 'nil' for ObjC methods, where it's much more likely that the
// variadic arguments form a list of object pointers.
SourceLocation MissingNilLoc
= getLocForEndOfToken(sentinelExpr->getLocEnd());
std::string NullValue;
if (calleeType == CT_Method && PP.isMacroDefined("nil"))
NullValue = "nil";
else if (getLangOpts().CPlusPlus11)
NullValue = "nullptr";
else if (PP.isMacroDefined("NULL"))
NullValue = "NULL";
else
NullValue = "(void*) 0";
if (MissingNilLoc.isInvalid())
Diag(Loc, diag::warn_missing_sentinel) << int(calleeType);
else
Diag(MissingNilLoc, diag::warn_missing_sentinel)
<< int(calleeType)
<< FixItHint::CreateInsertion(MissingNilLoc, ", " + NullValue);
Diag(D->getLocation(), diag::note_sentinel_here) << int(calleeType);
}
SourceRange Sema::getExprRange(Expr *E) const {
return E ? E->getSourceRange() : SourceRange();
}
//===----------------------------------------------------------------------===//
// Standard Promotions and Conversions
//===----------------------------------------------------------------------===//
/// DefaultFunctionArrayConversion (C99 6.3.2.1p3, C99 6.3.2.1p4).
ExprResult Sema::DefaultFunctionArrayConversion(Expr *E, bool Diagnose) {
// Handle any placeholder expressions which made it here.
if (E->getType()->isPlaceholderType()) {
ExprResult result = CheckPlaceholderExpr(E);
if (result.isInvalid()) return ExprError();
E = result.get();
}
QualType Ty = E->getType();
assert(!Ty.isNull() && "DefaultFunctionArrayConversion - missing type");
if (Ty->isFunctionType()) {
if (auto *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts()))
if (auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl()))
if (!checkAddressOfFunctionIsAvailable(FD, Diagnose, E->getExprLoc()))
return ExprError();
E = ImpCastExprToType(E, Context.getPointerType(Ty),
CK_FunctionToPointerDecay).get();
} else if (Ty->isArrayType()) {
// In C90 mode, arrays only promote to pointers if the array expression is
// an lvalue. The relevant legalese is C90 6.2.2.1p3: "an lvalue that has
// type 'array of type' is converted to an expression that has type 'pointer
// to type'...". In C99 this was changed to: C99 6.3.2.1p3: "an expression
// that has type 'array of type' ...". The relevant change is "an lvalue"
// (C90) to "an expression" (C99).
//
// C++ 4.2p1:
// An lvalue or rvalue of type "array of N T" or "array of unknown bound of
// T" can be converted to an rvalue of type "pointer to T".
//
if (getLangOpts().C99 || getLangOpts().CPlusPlus || E->isLValue())
E = ImpCastExprToType(E, Context.getArrayDecayedType(Ty),
CK_ArrayToPointerDecay).get();
}
return E;
}
static void CheckForNullPointerDereference(Sema &S, Expr *E) {
// Check to see if we are dereferencing a null pointer. If so,
// and if not volatile-qualified, this is undefined behavior that the
// optimizer will delete, so warn about it. People sometimes try to use this
// to get a deterministic trap and are surprised by clang's behavior. This
// only handles the pattern "*null", which is a very syntactic check.
if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E->IgnoreParenCasts()))
if (UO->getOpcode() == UO_Deref &&
UO->getSubExpr()->IgnoreParenCasts()->
isNullPointerConstant(S.Context, Expr::NPC_ValueDependentIsNotNull) &&
!UO->getType().isVolatileQualified()) {
S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
S.PDiag(diag::warn_indirection_through_null)
<< UO->getSubExpr()->getSourceRange());
S.DiagRuntimeBehavior(UO->getOperatorLoc(), UO,
S.PDiag(diag::note_indirection_through_null));
}
}
static void DiagnoseDirectIsaAccess(Sema &S, const ObjCIvarRefExpr *OIRE,
SourceLocation AssignLoc,
const Expr* RHS) {
const ObjCIvarDecl *IV = OIRE->getDecl();
if (!IV)
return;
DeclarationName MemberName = IV->getDeclName();
IdentifierInfo *Member = MemberName.getAsIdentifierInfo();
if (!Member || !Member->isStr("isa"))
return;
const Expr *Base = OIRE->getBase();
QualType BaseType = Base->getType();
if (OIRE->isArrow())
BaseType = BaseType->getPointeeType();
if (const ObjCObjectType *OTy = BaseType->getAs<ObjCObjectType>())
if (ObjCInterfaceDecl *IDecl = OTy->getInterface()) {
ObjCInterfaceDecl *ClassDeclared = nullptr;
ObjCIvarDecl *IV = IDecl->lookupInstanceVariable(Member, ClassDeclared);
if (!ClassDeclared->getSuperClass()
&& (*ClassDeclared->ivar_begin()) == IV) {
if (RHS) {
NamedDecl *ObjectSetClass =
S.LookupSingleName(S.TUScope,
&S.Context.Idents.get("object_setClass"),
SourceLocation(), S.LookupOrdinaryName);
if (ObjectSetClass) {
SourceLocation RHSLocEnd = S.getLocForEndOfToken(RHS->getLocEnd());
S.Diag(OIRE->getExprLoc(), diag::warn_objc_isa_assign) <<
FixItHint::CreateInsertion(OIRE->getLocStart(), "object_setClass(") <<
FixItHint::CreateReplacement(SourceRange(OIRE->getOpLoc(),
AssignLoc), ",") <<
FixItHint::CreateInsertion(RHSLocEnd, ")");
}
else
S.Diag(OIRE->getLocation(), diag::warn_objc_isa_assign);
} else {
NamedDecl *ObjectGetClass =
S.LookupSingleName(S.TUScope,
&S.Context.Idents.get("object_getClass"),
SourceLocation(), S.LookupOrdinaryName);
if (ObjectGetClass)
S.Diag(OIRE->getExprLoc(), diag::warn_objc_isa_use) <<
FixItHint::CreateInsertion(OIRE->getLocStart(), "object_getClass(") <<
FixItHint::CreateReplacement(
SourceRange(OIRE->getOpLoc(),
OIRE->getLocEnd()), ")");
else
S.Diag(OIRE->getLocation(), diag::warn_objc_isa_use);
}
S.Diag(IV->getLocation(), diag::note_ivar_decl);
}
}
}
ExprResult Sema::DefaultLvalueConversion(Expr *E) {
// Handle any placeholder expressions which made it here.
if (E->getType()->isPlaceholderType()) {
ExprResult result = CheckPlaceholderExpr(E);
if (result.isInvalid()) return ExprError();
E = result.get();
}
// C++ [conv.lval]p1:
// A glvalue of a non-function, non-array type T can be
// converted to a prvalue.
if (!E->isGLValue()) return E;
QualType T = E->getType();
assert(!T.isNull() && "r-value conversion on typeless expression?");
// We don't want to throw lvalue-to-rvalue casts on top of
// expressions of certain types in C++.
if (getLangOpts().CPlusPlus &&
(E->getType() == Context.OverloadTy ||
T->isDependentType() ||
T->isRecordType()))
return E;
// The C standard is actually really unclear on this point, and
// DR106 tells us what the result should be but not why. It's
// generally best to say that void types just doesn't undergo
// lvalue-to-rvalue at all. Note that expressions of unqualified
// 'void' type are never l-values, but qualified void can be.
if (T->isVoidType())
return E;
// OpenCL usually rejects direct accesses to values of 'half' type.
if (getLangOpts().OpenCL && !getOpenCLOptions().isEnabled("cl_khr_fp16") &&
T->isHalfType()) {
Diag(E->getExprLoc(), diag::err_opencl_half_load_store)
<< 0 << T;
return ExprError();
}
CheckForNullPointerDereference(*this, E);
if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(E->IgnoreParenCasts())) {
NamedDecl *ObjectGetClass = LookupSingleName(TUScope,
&Context.Idents.get("object_getClass"),
SourceLocation(), LookupOrdinaryName);
if (ObjectGetClass)
Diag(E->getExprLoc(), diag::warn_objc_isa_use) <<
FixItHint::CreateInsertion(OISA->getLocStart(), "object_getClass(") <<
FixItHint::CreateReplacement(
SourceRange(OISA->getOpLoc(), OISA->getIsaMemberLoc()), ")");
else
Diag(E->getExprLoc(), diag::warn_objc_isa_use);
}
else if (const ObjCIvarRefExpr *OIRE =
dyn_cast<ObjCIvarRefExpr>(E->IgnoreParenCasts()))
DiagnoseDirectIsaAccess(*this, OIRE, SourceLocation(), /* Expr*/nullptr);
// C++ [conv.lval]p1:
// [...] If T is a non-class type, the type of the prvalue is the
// cv-unqualified version of T. Otherwise, the type of the
// rvalue is T.
//
// C99 6.3.2.1p2:
// If the lvalue has qualified type, the value has the unqualified
// version of the type of the lvalue; otherwise, the value has the
// type of the lvalue.
if (T.hasQualifiers())
T = T.getUnqualifiedType();
// Under the MS ABI, lock down the inheritance model now.
if (T->isMemberPointerType() &&
Context.getTargetInfo().getCXXABI().isMicrosoft())
(void)isCompleteType(E->getExprLoc(), T);
UpdateMarkingForLValueToRValue(E);
// Loading a __weak object implicitly retains the value, so we need a cleanup to
// balance that.
if (E->getType().getObjCLifetime() == Qualifiers::OCL_Weak)
Cleanup.setExprNeedsCleanups(true);
ExprResult Res = ImplicitCastExpr::Create(Context, T, CK_LValueToRValue, E,
nullptr, VK_RValue);
// C11 6.3.2.1p2:
// ... if the lvalue has atomic type, the value has the non-atomic version
// of the type of the lvalue ...
if (const AtomicType *Atomic = T->getAs<AtomicType>()) {
T = Atomic->getValueType().getUnqualifiedType();
Res = ImplicitCastExpr::Create(Context, T, CK_AtomicToNonAtomic, Res.get(),
nullptr, VK_RValue);
}
return Res;
}
ExprResult Sema::DefaultFunctionArrayLvalueConversion(Expr *E, bool Diagnose) {
ExprResult Res = DefaultFunctionArrayConversion(E, Diagnose);
if (Res.isInvalid())
return ExprError();
Res = DefaultLvalueConversion(Res.get());
if (Res.isInvalid())
return ExprError();
return Res;
}
/// CallExprUnaryConversions - a special case of an unary conversion
/// performed on a function designator of a call expression.
ExprResult Sema::CallExprUnaryConversions(Expr *E) {
QualType Ty = E->getType();
ExprResult Res = E;
// Only do implicit cast for a function type, but not for a pointer
// to function type.
if (Ty->isFunctionType()) {
Res = ImpCastExprToType(E, Context.getPointerType(Ty),
CK_FunctionToPointerDecay).get();
if (Res.isInvalid())
return ExprError();
}
Res = DefaultLvalueConversion(Res.get());
if (Res.isInvalid())
return ExprError();
return Res.get();
}
/// UsualUnaryConversions - Performs various conversions that are common to most
/// operators (C99 6.3). The conversions of array and function types are
/// sometimes suppressed. For example, the array->pointer conversion doesn't
/// apply if the array is an argument to the sizeof or address (&) operators.
/// In these instances, this routine should *not* be called.
ExprResult Sema::UsualUnaryConversions(Expr *E) {
// First, convert to an r-value.
ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
if (Res.isInvalid())
return ExprError();
E = Res.get();
QualType Ty = E->getType();
assert(!Ty.isNull() && "UsualUnaryConversions - missing type");
// Half FP have to be promoted to float unless it is natively supported
if (Ty->isHalfType() && !getLangOpts().NativeHalfType)
return ImpCastExprToType(Res.get(), Context.FloatTy, CK_FloatingCast);
// Try to perform integral promotions if the object has a theoretically
// promotable type.
if (Ty->isIntegralOrUnscopedEnumerationType()) {
// C99 6.3.1.1p2:
//
// The following may be used in an expression wherever an int or
// unsigned int may be used:
// - an object or expression with an integer type whose integer
// conversion rank is less than or equal to the rank of int
// and unsigned int.
// - A bit-field of type _Bool, int, signed int, or unsigned int.
//
// If an int can represent all values of the original type, the
// value is converted to an int; otherwise, it is converted to an
// unsigned int. These are called the integer promotions. All
// other types are unchanged by the integer promotions.
QualType PTy = Context.isPromotableBitField(E);
if (!PTy.isNull()) {
E = ImpCastExprToType(E, PTy, CK_IntegralCast).get();
return E;
}
if (Ty->isPromotableIntegerType()) {
QualType PT = Context.getPromotedIntegerType(Ty);
E = ImpCastExprToType(E, PT, CK_IntegralCast).get();
return E;
}
}
return E;
}
/// DefaultArgumentPromotion (C99 6.5.2.2p6). Used for function calls that
/// do not have a prototype. Arguments that have type float or __fp16
/// are promoted to double. All other argument types are converted by
/// UsualUnaryConversions().
ExprResult Sema::DefaultArgumentPromotion(Expr *E) {
QualType Ty = E->getType();
assert(!Ty.isNull() && "DefaultArgumentPromotion - missing type");
ExprResult Res = UsualUnaryConversions(E);
if (Res.isInvalid())
return ExprError();
E = Res.get();
// If this is a 'float' or '__fp16' (CVR qualified or typedef)
// promote to double.
// Note that default argument promotion applies only to float (and
// half/fp16); it does not apply to _Float16.
const BuiltinType *BTy = Ty->getAs<BuiltinType>();
if (BTy && (BTy->getKind() == BuiltinType::Half ||
BTy->getKind() == BuiltinType::Float)) {
if (getLangOpts().OpenCL &&
!getOpenCLOptions().isEnabled("cl_khr_fp64")) {
if (BTy->getKind() == BuiltinType::Half) {
E = ImpCastExprToType(E, Context.FloatTy, CK_FloatingCast).get();
}
} else {
E = ImpCastExprToType(E, Context.DoubleTy, CK_FloatingCast).get();
}
}
// C++ performs lvalue-to-rvalue conversion as a default argument
// promotion, even on class types, but note:
// C++11 [conv.lval]p2:
// When an lvalue-to-rvalue conversion occurs in an unevaluated
// operand or a subexpression thereof the value contained in the
// referenced object is not accessed. Otherwise, if the glvalue
// has a class type, the conversion copy-initializes a temporary
// of type T from the glvalue and the result of the conversion
// is a prvalue for the temporary.
// FIXME: add some way to gate this entire thing for correctness in
// potentially potentially evaluated contexts.
if (getLangOpts().CPlusPlus && E->isGLValue() && !isUnevaluatedContext()) {
ExprResult Temp = PerformCopyInitialization(
InitializedEntity::InitializeTemporary(E->getType()),
E->getExprLoc(), E);
if (Temp.isInvalid())
return ExprError();
E = Temp.get();
}
return E;
}
/// Determine the degree of POD-ness for an expression.
/// Incomplete types are considered POD, since this check can be performed
/// when we're in an unevaluated context.
Sema::VarArgKind Sema::isValidVarArgType(const QualType &Ty) {
if (Ty->isIncompleteType()) {
// C++11 [expr.call]p7:
// After these conversions, if the argument does not have arithmetic,
// enumeration, pointer, pointer to member, or class type, the program
// is ill-formed.
//
// Since we've already performed array-to-pointer and function-to-pointer
// decay, the only such type in C++ is cv void. This also handles
// initializer lists as variadic arguments.
if (Ty->isVoidType())
return VAK_Invalid;
if (Ty->isObjCObjectType())
return VAK_Invalid;
return VAK_Valid;
}
if (Ty.isDestructedType() == QualType::DK_nontrivial_c_struct)
return VAK_Invalid;
if (Ty.isCXX98PODType(Context))
return VAK_Valid;
// C++11 [expr.call]p7:
// Passing a potentially-evaluated argument of class type (Clause 9)
// having a non-trivial copy constructor, a non-trivial move constructor,
// or a non-trivial destructor, with no corresponding parameter,
// is conditionally-supported with implementation-defined semantics.
if (getLangOpts().CPlusPlus11 && !Ty->isDependentType())
if (CXXRecordDecl *Record = Ty->getAsCXXRecordDecl())
if (!Record->hasNonTrivialCopyConstructor() &&
!Record->hasNonTrivialMoveConstructor() &&
!Record->hasNonTrivialDestructor())
return VAK_ValidInCXX11;
if (getLangOpts().ObjCAutoRefCount && Ty->isObjCLifetimeType())
return VAK_Valid;
if (Ty->isObjCObjectType())
return VAK_Invalid;
if (getLangOpts().MSVCCompat)
return VAK_MSVCUndefined;
// FIXME: In C++11, these cases are conditionally-supported, meaning we're
// permitted to reject them. We should consider doing so.
return VAK_Undefined;
}
void Sema::checkVariadicArgument(const Expr *E, VariadicCallType CT) {
// Don't allow one to pass an Objective-C interface to a vararg.
const QualType &Ty = E->getType();
VarArgKind VAK = isValidVarArgType(Ty);
// Complain about passing non-POD types through varargs.
switch (VAK) {
case VAK_ValidInCXX11:
DiagRuntimeBehavior(
E->getLocStart(), nullptr,
PDiag(diag::warn_cxx98_compat_pass_non_pod_arg_to_vararg)
<< Ty << CT);
LLVM_FALLTHROUGH;
case VAK_Valid:
if (Ty->isRecordType()) {
// This is unlikely to be what the user intended. If the class has a
// 'c_str' member function, the user probably meant to call that.
DiagRuntimeBehavior(E->getLocStart(), nullptr,
PDiag(diag::warn_pass_class_arg_to_vararg)
<< Ty << CT << hasCStrMethod(E) << ".c_str()");
}
break;
case VAK_Undefined:
case VAK_MSVCUndefined:
DiagRuntimeBehavior(
E->getLocStart(), nullptr,
PDiag(diag::warn_cannot_pass_non_pod_arg_to_vararg)
<< getLangOpts().CPlusPlus11 << Ty << CT);
break;
case VAK_Invalid:
if (Ty.isDestructedType() == QualType::DK_nontrivial_c_struct)
Diag(E->getLocStart(),
diag::err_cannot_pass_non_trivial_c_struct_to_vararg) << Ty << CT;
else if (Ty->isObjCObjectType())
DiagRuntimeBehavior(
E->getLocStart(), nullptr,
PDiag(diag::err_cannot_pass_objc_interface_to_vararg)
<< Ty << CT);
else
Diag(E->getLocStart(), diag::err_cannot_pass_to_vararg)
<< isa<InitListExpr>(E) << Ty << CT;
break;
}
}
/// DefaultVariadicArgumentPromotion - Like DefaultArgumentPromotion, but
/// will create a trap if the resulting type is not a POD type.
ExprResult Sema::DefaultVariadicArgumentPromotion(Expr *E, VariadicCallType CT,
FunctionDecl *FDecl) {
if (const BuiltinType *PlaceholderTy = E->getType()->getAsPlaceholderType()) {
// Strip the unbridged-cast placeholder expression off, if applicable.
if (PlaceholderTy->getKind() == BuiltinType::ARCUnbridgedCast &&
(CT == VariadicMethod ||
(FDecl && FDecl->hasAttr<CFAuditedTransferAttr>()))) {
E = stripARCUnbridgedCast(E);
// Otherwise, do normal placeholder checking.
} else {
ExprResult ExprRes = CheckPlaceholderExpr(E);
if (ExprRes.isInvalid())
return ExprError();
E = ExprRes.get();
}
}
ExprResult ExprRes = DefaultArgumentPromotion(E);
if (ExprRes.isInvalid())
return ExprError();
E = ExprRes.get();
// Diagnostics regarding non-POD argument types are
// emitted along with format string checking in Sema::CheckFunctionCall().
if (isValidVarArgType(E->getType()) == VAK_Undefined) {
// Turn this into a trap.
CXXScopeSpec SS;
SourceLocation TemplateKWLoc;
UnqualifiedId Name;
Name.setIdentifier(PP.getIdentifierInfo("__builtin_trap"),
E->getLocStart());
ExprResult TrapFn = ActOnIdExpression(TUScope, SS, TemplateKWLoc,
Name, true, false);
if (TrapFn.isInvalid())
return ExprError();
ExprResult Call = ActOnCallExpr(TUScope, TrapFn.get(),
E->getLocStart(), None,
E->getLocEnd());
if (Call.isInvalid())
return ExprError();
ExprResult Comma = ActOnBinOp(TUScope, E->getLocStart(), tok::comma,
Call.get(), E);
if (Comma.isInvalid())
return ExprError();
return Comma.get();
}
if (!getLangOpts().CPlusPlus &&
RequireCompleteType(E->getExprLoc(), E->getType(),
diag::err_call_incomplete_argument))
return ExprError();
return E;
}
/// Converts an integer to complex float type. Helper function of
/// UsualArithmeticConversions()
///
/// \return false if the integer expression is an integer type and is
/// successfully converted to the complex type.
static bool handleIntegerToComplexFloatConversion(Sema &S, ExprResult &IntExpr,
ExprResult &ComplexExpr,
QualType IntTy,
QualType ComplexTy,
bool SkipCast) {
if (IntTy->isComplexType() || IntTy->isRealFloatingType()) return true;
if (SkipCast) return false;
if (IntTy->isIntegerType()) {
QualType fpTy = cast<ComplexType>(ComplexTy)->getElementType();
IntExpr = S.ImpCastExprToType(IntExpr.get(), fpTy, CK_IntegralToFloating);
IntExpr = S.ImpCastExprToType(IntExpr.get(), ComplexTy,
CK_FloatingRealToComplex);
} else {
assert(IntTy->isComplexIntegerType());
IntExpr = S.ImpCastExprToType(IntExpr.get(), ComplexTy,
CK_IntegralComplexToFloatingComplex);
}
return false;
}
/// Handle arithmetic conversion with complex types. Helper function of
/// UsualArithmeticConversions()
static QualType handleComplexFloatConversion(Sema &S, ExprResult &LHS,
ExprResult &RHS, QualType LHSType,
QualType RHSType,
bool IsCompAssign) {
// if we have an integer operand, the result is the complex type.
if (!handleIntegerToComplexFloatConversion(S, RHS, LHS, RHSType, LHSType,
/*skipCast*/false))
return LHSType;
if (!handleIntegerToComplexFloatConversion(S, LHS, RHS, LHSType, RHSType,
/*skipCast*/IsCompAssign))
return RHSType;
// This handles complex/complex, complex/float, or float/complex.
// When both operands are complex, the shorter operand is converted to the
// type of the longer, and that is the type of the result. This corresponds
// to what is done when combining two real floating-point operands.
// The fun begins when size promotion occur across type domains.
// From H&S 6.3.4: When one operand is complex and the other is a real
// floating-point type, the less precise type is converted, within it's
// real or complex domain, to the precision of the other type. For example,
// when combining a "long double" with a "double _Complex", the
// "double _Complex" is promoted to "long double _Complex".
// Compute the rank of the two types, regardless of whether they are complex.
int Order = S.Context.getFloatingTypeOrder(LHSType, RHSType);
auto *LHSComplexType = dyn_cast<ComplexType>(LHSType);
auto *RHSComplexType = dyn_cast<ComplexType>(RHSType);
QualType LHSElementType =
LHSComplexType ? LHSComplexType->getElementType() : LHSType;
QualType RHSElementType =
RHSComplexType ? RHSComplexType->getElementType() : RHSType;
QualType ResultType = S.Context.getComplexType(LHSElementType);
if (Order < 0) {
// Promote the precision of the LHS if not an assignment.
ResultType = S.Context.getComplexType(RHSElementType);
if (!IsCompAssign) {
if (LHSComplexType)
LHS =
S.ImpCastExprToType(LHS.get(), ResultType, CK_FloatingComplexCast);
else
LHS = S.ImpCastExprToType(LHS.get(), RHSElementType, CK_FloatingCast);
}
} else if (Order > 0) {
// Promote the precision of the RHS.
if (RHSComplexType)
RHS = S.ImpCastExprToType(RHS.get(), ResultType, CK_FloatingComplexCast);
else
RHS = S.ImpCastExprToType(RHS.get(), LHSElementType, CK_FloatingCast);
}
return ResultType;
}
/// Handle arithmetic conversion from integer to float. Helper function
/// of UsualArithmeticConversions()
static QualType handleIntToFloatConversion(Sema &S, ExprResult &FloatExpr,
ExprResult &IntExpr,
QualType FloatTy, QualType IntTy,
bool ConvertFloat, bool ConvertInt) {
if (IntTy->isIntegerType()) {
if (ConvertInt)
// Convert intExpr to the lhs floating point type.
IntExpr = S.ImpCastExprToType(IntExpr.get(), FloatTy,
CK_IntegralToFloating);
return FloatTy;
}
// Convert both sides to the appropriate complex float.
assert(IntTy->isComplexIntegerType());
QualType result = S.Context.getComplexType(FloatTy);
// _Complex int -> _Complex float
if (ConvertInt)
IntExpr = S.ImpCastExprToType(IntExpr.get(), result,
CK_IntegralComplexToFloatingComplex);
// float -> _Complex float
if (ConvertFloat)
FloatExpr = S.ImpCastExprToType(FloatExpr.get(), result,
CK_FloatingRealToComplex);
return result;
}
/// Handle arithmethic conversion with floating point types. Helper
/// function of UsualArithmeticConversions()
static QualType handleFloatConversion(Sema &S, ExprResult &LHS,
ExprResult &RHS, QualType LHSType,
QualType RHSType, bool IsCompAssign) {
bool LHSFloat = LHSType->isRealFloatingType();
bool RHSFloat = RHSType->isRealFloatingType();
// If we have two real floating types, convert the smaller operand
// to the bigger result.
if (LHSFloat && RHSFloat) {
int order = S.Context.getFloatingTypeOrder(LHSType, RHSType);
if (order > 0) {
RHS = S.ImpCastExprToType(RHS.get(), LHSType, CK_FloatingCast);
return LHSType;
}
assert(order < 0 && "illegal float comparison");
if (!IsCompAssign)
LHS = S.ImpCastExprToType(LHS.get(), RHSType, CK_FloatingCast);
return RHSType;
}
if (LHSFloat) {
// Half FP has to be promoted to float unless it is natively supported
if (LHSType->isHalfType() && !S.getLangOpts().NativeHalfType)
LHSType = S.Context.FloatTy;
return handleIntToFloatConversion(S, LHS, RHS, LHSType, RHSType,
/*convertFloat=*/!IsCompAssign,
/*convertInt=*/ true);
}
assert(RHSFloat);
return handleIntToFloatConversion(S, RHS, LHS, RHSType, LHSType,
/*convertInt=*/ true,
/*convertFloat=*/!IsCompAssign);
}
/// Diagnose attempts to convert between __float128 and long double if
/// there is no support for such conversion. Helper function of
/// UsualArithmeticConversions().
static bool unsupportedTypeConversion(const Sema &S, QualType LHSType,
QualType RHSType) {
/* No issue converting if at least one of the types is not a floating point
type or the two types have the same rank.
*/
if (!LHSType->isFloatingType() || !RHSType->isFloatingType() ||
S.Context.getFloatingTypeOrder(LHSType, RHSType) == 0)
return false;
assert(LHSType->isFloatingType() && RHSType->isFloatingType() &&
"The remaining types must be floating point types.");
auto *LHSComplex = LHSType->getAs<ComplexType>();
auto *RHSComplex = RHSType->getAs<ComplexType>();
QualType LHSElemType = LHSComplex ?
LHSComplex->getElementType() : LHSType;
QualType RHSElemType = RHSComplex ?
RHSComplex->getElementType() : RHSType;
// No issue if the two types have the same representation
if (&S.Context.getFloatTypeSemantics(LHSElemType) ==
&S.Context.getFloatTypeSemantics(RHSElemType))
return false;
bool Float128AndLongDouble = (LHSElemType == S.Context.Float128Ty &&
RHSElemType == S.Context.LongDoubleTy);
Float128AndLongDouble |= (LHSElemType == S.Context.LongDoubleTy &&
RHSElemType == S.Context.Float128Ty);
// We've handled the situation where __float128 and long double have the same
// representation. We allow all conversions for all possible long double types
// except PPC's double double.
return Float128AndLongDouble &&
(&S.Context.getFloatTypeSemantics(S.Context.LongDoubleTy) ==
&llvm::APFloat::PPCDoubleDouble());
}
typedef ExprResult PerformCastFn(Sema &S, Expr *operand, QualType toType);
namespace {
/// These helper callbacks are placed in an anonymous namespace to
/// permit their use as function template parameters.
ExprResult doIntegralCast(Sema &S, Expr *op, QualType toType) {
return S.ImpCastExprToType(op, toType, CK_IntegralCast);
}
ExprResult doComplexIntegralCast(Sema &S, Expr *op, QualType toType) {
return S.ImpCastExprToType(op, S.Context.getComplexType(toType),
CK_IntegralComplexCast);
}
}
/// Handle integer arithmetic conversions. Helper function of
/// UsualArithmeticConversions()
template <PerformCastFn doLHSCast, PerformCastFn doRHSCast>
static QualType handleIntegerConversion(Sema &S, ExprResult &LHS,
ExprResult &RHS, QualType LHSType,
QualType RHSType, bool IsCompAssign) {
// The rules for this case are in C99 6.3.1.8
int order = S.Context.getIntegerTypeOrder(LHSType, RHSType);
bool LHSSigned = LHSType->hasSignedIntegerRepresentation();
bool RHSSigned = RHSType->hasSignedIntegerRepresentation();
if (LHSSigned == RHSSigned) {
// Same signedness; use the higher-ranked type
if (order >= 0) {
RHS = (*doRHSCast)(S, RHS.get(), LHSType);
return LHSType;
} else if (!IsCompAssign)
LHS = (*doLHSCast)(S, LHS.get(), RHSType);
return RHSType;
} else if (order != (LHSSigned ? 1 : -1)) {
// The unsigned type has greater than or equal rank to the
// signed type, so use the unsigned type
if (RHSSigned) {
RHS = (*doRHSCast)(S, RHS.get(), LHSType);
return LHSType;
} else if (!IsCompAssign)
LHS = (*doLHSCast)(S, LHS.get(), RHSType);
return RHSType;
} else if (S.Context.getIntWidth(LHSType) != S.Context.getIntWidth(RHSType)) {
// The two types are different widths; if we are here, that
// means the signed type is larger than the unsigned type, so
// use the signed type.
if (LHSSigned) {
RHS = (*doRHSCast)(S, RHS.get(), LHSType);
return LHSType;
} else if (!IsCompAssign)
LHS = (*doLHSCast)(S, LHS.get(), RHSType);
return RHSType;
} else {
// The signed type is higher-ranked than the unsigned type,
// but isn't actually any bigger (like unsigned int and long
// on most 32-bit systems). Use the unsigned type corresponding
// to the signed type.
QualType result =
S.Context.getCorrespondingUnsignedType(LHSSigned ? LHSType : RHSType);
RHS = (*doRHSCast)(S, RHS.get(), result);
if (!IsCompAssign)
LHS = (*doLHSCast)(S, LHS.get(), result);
return result;
}
}
/// Handle conversions with GCC complex int extension. Helper function
/// of UsualArithmeticConversions()
static QualType handleComplexIntConversion(Sema &S, ExprResult &LHS,
ExprResult &RHS, QualType LHSType,
QualType RHSType,
bool IsCompAssign) {
const ComplexType *LHSComplexInt = LHSType->getAsComplexIntegerType();
const ComplexType *RHSComplexInt = RHSType->getAsComplexIntegerType();
if (LHSComplexInt && RHSComplexInt) {
QualType LHSEltType = LHSComplexInt->getElementType();
QualType RHSEltType = RHSComplexInt->getElementType();
QualType ScalarType =
handleIntegerConversion<doComplexIntegralCast, doComplexIntegralCast>
(S, LHS, RHS, LHSEltType, RHSEltType, IsCompAssign);
return S.Context.getComplexType(ScalarType);
}
if (LHSComplexInt) {
QualType LHSEltType = LHSComplexInt->getElementType();
QualType ScalarType =
handleIntegerConversion<doComplexIntegralCast, doIntegralCast>
(S, LHS, RHS, LHSEltType, RHSType, IsCompAssign);
QualType ComplexType = S.Context.getComplexType(ScalarType);
RHS = S.ImpCastExprToType(RHS.get(), ComplexType,
CK_IntegralRealToComplex);
return ComplexType;
}
assert(RHSComplexInt);
QualType RHSEltType = RHSComplexInt->getElementType();
QualType ScalarType =
handleIntegerConversion<doIntegralCast, doComplexIntegralCast>
(S, LHS, RHS, LHSType, RHSEltType, IsCompAssign);
QualType ComplexType = S.Context.getComplexType(ScalarType);
if (!IsCompAssign)
LHS = S.ImpCastExprToType(LHS.get(), ComplexType,
CK_IntegralRealToComplex);
return ComplexType;
}
/// UsualArithmeticConversions - Performs various conversions that are common to
/// binary operators (C99 6.3.1.8). If both operands aren't arithmetic, this
/// routine returns the first non-arithmetic type found. The client is
/// responsible for emitting appropriate error diagnostics.
QualType Sema::UsualArithmeticConversions(ExprResult &LHS, ExprResult &RHS,
bool IsCompAssign) {
if (!IsCompAssign) {
LHS = UsualUnaryConversions(LHS.get());
if (LHS.isInvalid())
return QualType();
}
RHS = UsualUnaryConversions(RHS.get());
if (RHS.isInvalid())
return QualType();
// For conversion purposes, we ignore any qualifiers.
// For example, "const float" and "float" are equivalent.
QualType LHSType =
Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType();
QualType RHSType =
Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType();
// For conversion purposes, we ignore any atomic qualifier on the LHS.
if (const AtomicType *AtomicLHS = LHSType->getAs<AtomicType>())
LHSType = AtomicLHS->getValueType();
// If both types are identical, no conversion is needed.
if (LHSType == RHSType)
return LHSType;
// If either side is a non-arithmetic type (e.g. a pointer), we are done.
// The caller can deal with this (e.g. pointer + int).
if (!LHSType->isArithmeticType() || !RHSType->isArithmeticType())
return QualType();
// Apply unary and bitfield promotions to the LHS's type.
QualType LHSUnpromotedType = LHSType;
if (LHSType->isPromotableIntegerType())
LHSType = Context.getPromotedIntegerType(LHSType);
QualType LHSBitfieldPromoteTy = Context.isPromotableBitField(LHS.get());
if (!LHSBitfieldPromoteTy.isNull())
LHSType = LHSBitfieldPromoteTy;
if (LHSType != LHSUnpromotedType && !IsCompAssign)
LHS = ImpCastExprToType(LHS.get(), LHSType, CK_IntegralCast);
// If both types are identical, no conversion is needed.
if (LHSType == RHSType)
return LHSType;
// At this point, we have two different arithmetic types.
// Diagnose attempts to convert between __float128 and long double where
// such conversions currently can't be handled.
if (unsupportedTypeConversion(*this, LHSType, RHSType))
return QualType();
// Handle complex types first (C99 6.3.1.8p1).
if (LHSType->isComplexType() || RHSType->isComplexType())
return handleComplexFloatConversion(*this, LHS, RHS, LHSType, RHSType,
IsCompAssign);
// Now handle "real" floating types (i.e. float, double, long double).
if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType())
return handleFloatConversion(*this, LHS, RHS, LHSType, RHSType,
IsCompAssign);
// Handle GCC complex int extension.
if (LHSType->isComplexIntegerType() || RHSType->isComplexIntegerType())
return handleComplexIntConversion(*this, LHS, RHS, LHSType, RHSType,
IsCompAssign);
// Finally, we have two differing integer types.
return handleIntegerConversion<doIntegralCast, doIntegralCast>
(*this, LHS, RHS, LHSType, RHSType, IsCompAssign);
}
//===----------------------------------------------------------------------===//
// Semantic Analysis for various Expression Types
//===----------------------------------------------------------------------===//
ExprResult
Sema::ActOnGenericSelectionExpr(SourceLocation KeyLoc,
SourceLocation DefaultLoc,
SourceLocation RParenLoc,
Expr *ControllingExpr,
ArrayRef<ParsedType> ArgTypes,
ArrayRef<Expr *> ArgExprs) {
unsigned NumAssocs = ArgTypes.size();
assert(NumAssocs == ArgExprs.size());
TypeSourceInfo **Types = new TypeSourceInfo*[NumAssocs];
for (unsigned i = 0; i < NumAssocs; ++i) {
if (ArgTypes[i])
(void) GetTypeFromParser(ArgTypes[i], &Types[i]);
else
Types[i] = nullptr;
}
ExprResult ER = CreateGenericSelectionExpr(KeyLoc, DefaultLoc, RParenLoc,
ControllingExpr,
llvm::makeArrayRef(Types, NumAssocs),
ArgExprs);
delete [] Types;
return ER;
}
ExprResult
Sema::CreateGenericSelectionExpr(SourceLocation KeyLoc,
SourceLocation DefaultLoc,
SourceLocation RParenLoc,
Expr *ControllingExpr,
ArrayRef<TypeSourceInfo *> Types,
ArrayRef<Expr *> Exprs) {
unsigned NumAssocs = Types.size();
assert(NumAssocs == Exprs.size());
// Decay and strip qualifiers for the controlling expression type, and handle
// placeholder type replacement. See committee discussion from WG14 DR423.
{
EnterExpressionEvaluationContext Unevaluated(
*this, Sema::ExpressionEvaluationContext::Unevaluated);
ExprResult R = DefaultFunctionArrayLvalueConversion(ControllingExpr);
if (R.isInvalid())
return ExprError();
ControllingExpr = R.get();
}
// The controlling expression is an unevaluated operand, so side effects are
// likely unintended.
if (!inTemplateInstantiation() &&
ControllingExpr->HasSideEffects(Context, false))
Diag(ControllingExpr->getExprLoc(),
diag::warn_side_effects_unevaluated_context);
bool TypeErrorFound = false,
IsResultDependent = ControllingExpr->isTypeDependent(),
ContainsUnexpandedParameterPack
= ControllingExpr->containsUnexpandedParameterPack();
for (unsigned i = 0; i < NumAssocs; ++i) {
if (Exprs[i]->containsUnexpandedParameterPack())
ContainsUnexpandedParameterPack = true;
if (Types[i]) {
if (Types[i]->getType()->containsUnexpandedParameterPack())
ContainsUnexpandedParameterPack = true;
if (Types[i]->getType()->isDependentType()) {
IsResultDependent = true;
} else {
// C11 6.5.1.1p2 "The type name in a generic association shall specify a
// complete object type other than a variably modified type."
unsigned D = 0;
if (Types[i]->getType()->isIncompleteType())
D = diag::err_assoc_type_incomplete;
else if (!Types[i]->getType()->isObjectType())
D = diag::err_assoc_type_nonobject;
else if (Types[i]->getType()->isVariablyModifiedType())
D = diag::err_assoc_type_variably_modified;
if (D != 0) {
Diag(Types[i]->getTypeLoc().getBeginLoc(), D)
<< Types[i]->getTypeLoc().getSourceRange()
<< Types[i]->getType();
TypeErrorFound = true;
}
// C11 6.5.1.1p2 "No two generic associations in the same generic
// selection shall specify compatible types."
for (unsigned j = i+1; j < NumAssocs; ++j)
if (Types[j] && !Types[j]->getType()->isDependentType() &&
Context.typesAreCompatible(Types[i]->getType(),
Types[j]->getType())) {
Diag(Types[j]->getTypeLoc().getBeginLoc(),
diag::err_assoc_compatible_types)
<< Types[j]->getTypeLoc().getSourceRange()
<< Types[j]->getType()
<< Types[i]->getType();
Diag(Types[i]->getTypeLoc().getBeginLoc(),
diag::note_compat_assoc)
<< Types[i]->getTypeLoc().getSourceRange()
<< Types[i]->getType();
TypeErrorFound = true;
}
}
}
}
if (TypeErrorFound)
return ExprError();
// If we determined that the generic selection is result-dependent, don't
// try to compute the result expression.
if (IsResultDependent)
return new (Context) GenericSelectionExpr(
Context, KeyLoc, ControllingExpr, Types, Exprs, DefaultLoc, RParenLoc,
ContainsUnexpandedParameterPack);
SmallVector<unsigned, 1> CompatIndices;
unsigned DefaultIndex = -1U;
for (unsigned i = 0; i < NumAssocs; ++i) {
if (!Types[i])
DefaultIndex = i;
else if (Context.typesAreCompatible(ControllingExpr->getType(),
Types[i]->getType()))
CompatIndices.push_back(i);
}
// C11 6.5.1.1p2 "The controlling expression of a generic selection shall have
// type compatible with at most one of the types named in its generic
// association list."
if (CompatIndices.size() > 1) {
// We strip parens here because the controlling expression is typically
// parenthesized in macro definitions.
ControllingExpr = ControllingExpr->IgnoreParens();
Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_multi_match)
<< ControllingExpr->getSourceRange() << ControllingExpr->getType()
<< (unsigned) CompatIndices.size();
for (unsigned I : CompatIndices) {
Diag(Types[I]->getTypeLoc().getBeginLoc(),
diag::note_compat_assoc)
<< Types[I]->getTypeLoc().getSourceRange()
<< Types[I]->getType();
}
return ExprError();
}
// C11 6.5.1.1p2 "If a generic selection has no default generic association,
// its controlling expression shall have type compatible with exactly one of
// the types named in its generic association list."
if (DefaultIndex == -1U && CompatIndices.size() == 0) {
// We strip parens here because the controlling expression is typically
// parenthesized in macro definitions.
ControllingExpr = ControllingExpr->IgnoreParens();
Diag(ControllingExpr->getLocStart(), diag::err_generic_sel_no_match)
<< ControllingExpr->getSourceRange() << ControllingExpr->getType();
return ExprError();
}
// C11 6.5.1.1p3 "If a generic selection has a generic association with a
// type name that is compatible with the type of the controlling expression,
// then the result expression of the generic selection is the expression
// in that generic association. Otherwise, the result expression of the
// generic selection is the expression in the default generic association."
unsigned ResultIndex =
CompatIndices.size() ? CompatIndices[0] : DefaultIndex;
return new (Context) GenericSelectionExpr(
Context, KeyLoc, ControllingExpr, Types, Exprs, DefaultLoc, RParenLoc,
ContainsUnexpandedParameterPack, ResultIndex);
}
/// getUDSuffixLoc - Create a SourceLocation for a ud-suffix, given the
/// location of the token and the offset of the ud-suffix within it.
static SourceLocation getUDSuffixLoc(Sema &S, SourceLocation TokLoc,
unsigned Offset) {
return Lexer::AdvanceToTokenCharacter(TokLoc, Offset, S.getSourceManager(),
S.getLangOpts());
}
/// BuildCookedLiteralOperatorCall - A user-defined literal was found. Look up
/// the corresponding cooked (non-raw) literal operator, and build a call to it.
static ExprResult BuildCookedLiteralOperatorCall(Sema &S, Scope *Scope,
IdentifierInfo *UDSuffix,
SourceLocation UDSuffixLoc,
ArrayRef<Expr*> Args,
SourceLocation LitEndLoc) {
assert(Args.size() <= 2 && "too many arguments for literal operator");
QualType ArgTy[2];
for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
ArgTy[ArgIdx] = Args[ArgIdx]->getType();
if (ArgTy[ArgIdx]->isArrayType())
ArgTy[ArgIdx] = S.Context.getArrayDecayedType(ArgTy[ArgIdx]);
}
DeclarationName OpName =
S.Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix);
DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
LookupResult R(S, OpName, UDSuffixLoc, Sema::LookupOrdinaryName);
if (S.LookupLiteralOperator(Scope, R, llvm::makeArrayRef(ArgTy, Args.size()),
/*AllowRaw*/ false, /*AllowTemplate*/ false,
/*AllowStringTemplate*/ false,
/*DiagnoseMissing*/ true) == Sema::LOLR_Error)
return ExprError();
return S.BuildLiteralOperatorCall(R, OpNameInfo, Args, LitEndLoc);
}
/// ActOnStringLiteral - The specified tokens were lexed as pasted string
/// fragments (e.g. "foo" "bar" L"baz"). The result string has to handle string
/// concatenation ([C99 5.1.1.2, translation phase #6]), so it may come from
/// multiple tokens. However, the common case is that StringToks points to one
/// string.
///
ExprResult
Sema::ActOnStringLiteral(ArrayRef<Token> StringToks, Scope *UDLScope) {
assert(!StringToks.empty() && "Must have at least one string!");
StringLiteralParser Literal(StringToks, PP);
if (Literal.hadError)
return ExprError();
SmallVector<SourceLocation, 4> StringTokLocs;
for (const Token &Tok : StringToks)
StringTokLocs.push_back(Tok.getLocation());
QualType CharTy = Context.CharTy;
StringLiteral::StringKind Kind = StringLiteral::Ascii;
if (Literal.isWide()) {
CharTy = Context.getWideCharType();
Kind = StringLiteral::Wide;
} else if (Literal.isUTF8()) {
if (getLangOpts().Char8)
CharTy = Context.Char8Ty;
Kind = StringLiteral::UTF8;
} else if (Literal.isUTF16()) {
CharTy = Context.Char16Ty;
Kind = StringLiteral::UTF16;
} else if (Literal.isUTF32()) {
CharTy = Context.Char32Ty;
Kind = StringLiteral::UTF32;
} else if (Literal.isPascal()) {
CharTy = Context.UnsignedCharTy;
}
QualType CharTyConst = CharTy;
// A C++ string literal has a const-qualified element type (C++ 2.13.4p1).
if (getLangOpts().CPlusPlus || getLangOpts().ConstStrings)
CharTyConst.addConst();
CharTyConst = Context.adjustStringLiteralBaseType(CharTyConst);
// Get an array type for the string, according to C99 6.4.5. This includes
// the nul terminator character as well as the string length for pascal
// strings.
QualType StrTy = Context.getConstantArrayType(
CharTyConst, llvm::APInt(32, Literal.GetNumStringChars() + 1),
ArrayType::Normal, 0);
// Pass &StringTokLocs[0], StringTokLocs.size() to factory!
StringLiteral *Lit = StringLiteral::Create(Context, Literal.GetString(),
Kind, Literal.Pascal, StrTy,
&StringTokLocs[0],
StringTokLocs.size());
if (Literal.getUDSuffix().empty())
return Lit;
// We're building a user-defined literal.
IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix());
SourceLocation UDSuffixLoc =
getUDSuffixLoc(*this, StringTokLocs[Literal.getUDSuffixToken()],
Literal.getUDSuffixOffset());
// Make sure we're allowed user-defined literals here.
if (!UDLScope)
return ExprError(Diag(UDSuffixLoc, diag::err_invalid_string_udl));
// C++11 [lex.ext]p5: The literal L is treated as a call of the form
// operator "" X (str, len)
QualType SizeType = Context.getSizeType();
DeclarationName OpName =
Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix);
DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
QualType ArgTy[] = {
Context.getArrayDecayedType(StrTy), SizeType
};
LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName);
switch (LookupLiteralOperator(UDLScope, R, ArgTy,
/*AllowRaw*/ false, /*AllowTemplate*/ false,
/*AllowStringTemplate*/ true,
/*DiagnoseMissing*/ true)) {
case LOLR_Cooked: {
llvm::APInt Len(Context.getIntWidth(SizeType), Literal.GetNumStringChars());
IntegerLiteral *LenArg = IntegerLiteral::Create(Context, Len, SizeType,
StringTokLocs[0]);
Expr *Args[] = { Lit, LenArg };
return BuildLiteralOperatorCall(R, OpNameInfo, Args, StringTokLocs.back());
}
case LOLR_StringTemplate: {
TemplateArgumentListInfo ExplicitArgs;
unsigned CharBits = Context.getIntWidth(CharTy);
bool CharIsUnsigned = CharTy->isUnsignedIntegerType();
llvm::APSInt Value(CharBits, CharIsUnsigned);
TemplateArgument TypeArg(CharTy);
TemplateArgumentLocInfo TypeArgInfo(Context.getTrivialTypeSourceInfo(CharTy));
ExplicitArgs.addArgument(TemplateArgumentLoc(TypeArg, TypeArgInfo));
for (unsigned I = 0, N = Lit->getLength(); I != N; ++I) {
Value = Lit->getCodeUnit(I);
TemplateArgument Arg(Context, Value, CharTy);
TemplateArgumentLocInfo ArgInfo;
ExplicitArgs.addArgument(TemplateArgumentLoc(Arg, ArgInfo));
}
return BuildLiteralOperatorCall(R, OpNameInfo, None, StringTokLocs.back(),
&ExplicitArgs);
}
case LOLR_Raw:
case LOLR_Template:
case LOLR_ErrorNoDiagnostic:
llvm_unreachable("unexpected literal operator lookup result");
case LOLR_Error:
return ExprError();
}
llvm_unreachable("unexpected literal operator lookup result");
}
ExprResult
Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
SourceLocation Loc,
const CXXScopeSpec *SS) {
DeclarationNameInfo NameInfo(D->getDeclName(), Loc);
return BuildDeclRefExpr(D, Ty, VK, NameInfo, SS);
}
/// BuildDeclRefExpr - Build an expression that references a
/// declaration that does not require a closure capture.
ExprResult
Sema::BuildDeclRefExpr(ValueDecl *D, QualType Ty, ExprValueKind VK,
const DeclarationNameInfo &NameInfo,
const CXXScopeSpec *SS, NamedDecl *FoundD,
const TemplateArgumentListInfo *TemplateArgs) {
bool RefersToCapturedVariable =
isa<VarDecl>(D) &&
NeedToCaptureVariable(cast<VarDecl>(D), NameInfo.getLoc());
DeclRefExpr *E;
if (isa<VarTemplateSpecializationDecl>(D)) {
VarTemplateSpecializationDecl *VarSpec =
cast<VarTemplateSpecializationDecl>(D);
E = DeclRefExpr::Create(Context, SS ? SS->getWithLocInContext(Context)
: NestedNameSpecifierLoc(),
VarSpec->getTemplateKeywordLoc(), D,
RefersToCapturedVariable, NameInfo.getLoc(), Ty, VK,
FoundD, TemplateArgs);
} else {
assert(!TemplateArgs && "No template arguments for non-variable"
" template specialization references");
E = DeclRefExpr::Create(Context, SS ? SS->getWithLocInContext(Context)
: NestedNameSpecifierLoc(),
SourceLocation(), D, RefersToCapturedVariable,
NameInfo, Ty, VK, FoundD);
}
MarkDeclRefReferenced(E);
if (getLangOpts().ObjCWeak && isa<VarDecl>(D) &&
Ty.getObjCLifetime() == Qualifiers::OCL_Weak && !isUnevaluatedContext() &&
!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, E->getLocStart()))
getCurFunction()->recordUseOfWeak(E);
FieldDecl *FD = dyn_cast<FieldDecl>(D);
if (IndirectFieldDecl *IFD = dyn_cast<IndirectFieldDecl>(D))
FD = IFD->getAnonField();
if (FD) {
UnusedPrivateFields.remove(FD);
// Just in case we're building an illegal pointer-to-member.
if (FD->isBitField())
E->setObjectKind(OK_BitField);
}
// C++ [expr.prim]/8: The expression [...] is a bit-field if the identifier
// designates a bit-field.
if (auto *BD = dyn_cast<BindingDecl>(D))
if (auto *BE = BD->getBinding())
E->setObjectKind(BE->getObjectKind());
return E;
}
/// Decomposes the given name into a DeclarationNameInfo, its location, and
/// possibly a list of template arguments.
///
/// If this produces template arguments, it is permitted to call
/// DecomposeTemplateName.
///
/// This actually loses a lot of source location information for
/// non-standard name kinds; we should consider preserving that in
/// some way.
void
Sema::DecomposeUnqualifiedId(const UnqualifiedId &Id,
TemplateArgumentListInfo &Buffer,
DeclarationNameInfo &NameInfo,
const TemplateArgumentListInfo *&TemplateArgs) {
if (Id.getKind() == UnqualifiedIdKind::IK_TemplateId) {
Buffer.setLAngleLoc(Id.TemplateId->LAngleLoc);
Buffer.setRAngleLoc(Id.TemplateId->RAngleLoc);
ASTTemplateArgsPtr TemplateArgsPtr(Id.TemplateId->getTemplateArgs(),
Id.TemplateId->NumArgs);
translateTemplateArguments(TemplateArgsPtr, Buffer);
TemplateName TName = Id.TemplateId->Template.get();
SourceLocation TNameLoc = Id.TemplateId->TemplateNameLoc;
NameInfo = Context.getNameForTemplate(TName, TNameLoc);
TemplateArgs = &Buffer;
} else {
NameInfo = GetNameFromUnqualifiedId(Id);
TemplateArgs = nullptr;
}
}
static void emitEmptyLookupTypoDiagnostic(
const TypoCorrection &TC, Sema &SemaRef, const CXXScopeSpec &SS,
DeclarationName Typo, SourceLocation TypoLoc, ArrayRef<Expr *> Args,
unsigned DiagnosticID, unsigned DiagnosticSuggestID) {
DeclContext *Ctx =
SS.isEmpty() ? nullptr : SemaRef.computeDeclContext(SS, false);
if (!TC) {
// Emit a special diagnostic for failed member lookups.
// FIXME: computing the declaration context might fail here (?)
if (Ctx)
SemaRef.Diag(TypoLoc, diag::err_no_member) << Typo << Ctx
<< SS.getRange();
else
SemaRef.Diag(TypoLoc, DiagnosticID) << Typo;
return;
}
std::string CorrectedStr = TC.getAsString(SemaRef.getLangOpts());
bool DroppedSpecifier =
TC.WillReplaceSpecifier() && Typo.getAsString() == CorrectedStr;
unsigned NoteID = TC.getCorrectionDeclAs<ImplicitParamDecl>()
? diag::note_implicit_param_decl
: diag::note_previous_decl;
if (!Ctx)
SemaRef.diagnoseTypo(TC, SemaRef.PDiag(DiagnosticSuggestID) << Typo,
SemaRef.PDiag(NoteID));
else
SemaRef.diagnoseTypo(TC, SemaRef.PDiag(diag::err_no_member_suggest)
<< Typo << Ctx << DroppedSpecifier
<< SS.getRange(),
SemaRef.PDiag(NoteID));
}
/// Diagnose an empty lookup.
///
/// \return false if new lookup candidates were found
bool
Sema::DiagnoseEmptyLookup(Scope *S, CXXScopeSpec &SS, LookupResult &R,
std::unique_ptr<CorrectionCandidateCallback> CCC,
TemplateArgumentListInfo *ExplicitTemplateArgs,
ArrayRef<Expr *> Args, TypoExpr **Out) {
DeclarationName Name = R.getLookupName();
unsigned diagnostic = diag::err_undeclared_var_use;
unsigned diagnostic_suggest = diag::err_undeclared_var_use_suggest;
if (Name.getNameKind() == DeclarationName::CXXOperatorName ||
Name.getNameKind() == DeclarationName::CXXLiteralOperatorName ||
Name.getNameKind() == DeclarationName::CXXConversionFunctionName) {
diagnostic = diag::err_undeclared_use;
diagnostic_suggest = diag::err_undeclared_use_suggest;
}
// If the original lookup was an unqualified lookup, fake an
// unqualified lookup. This is useful when (for example) the
// original lookup would not have found something because it was a
// dependent name.
DeclContext *DC = SS.isEmpty() ? CurContext : nullptr;
while (DC) {
if (isa<CXXRecordDecl>(DC)) {
LookupQualifiedName(R, DC);
if (!R.empty()) {
// Don't give errors about ambiguities in this lookup.
R.suppressDiagnostics();
// During a default argument instantiation the CurContext points
// to a CXXMethodDecl; but we can't apply a this-> fixit inside a
// function parameter list, hence add an explicit check.
bool isDefaultArgument =
!CodeSynthesisContexts.empty() &&
CodeSynthesisContexts.back().Kind ==
CodeSynthesisContext::DefaultFunctionArgumentInstantiation;
CXXMethodDecl *CurMethod = dyn_cast<CXXMethodDecl>(CurContext);
bool isInstance = CurMethod &&
CurMethod->isInstance() &&
DC == CurMethod->getParent() && !isDefaultArgument;
// Give a code modification hint to insert 'this->'.
// TODO: fixit for inserting 'Base<T>::' in the other cases.
// Actually quite difficult!
if (getLangOpts().MSVCCompat)
diagnostic = diag::ext_found_via_dependent_bases_lookup;
if (isInstance) {
Diag(R.getNameLoc(), diagnostic) << Name
<< FixItHint::CreateInsertion(R.getNameLoc(), "this->");
CheckCXXThisCapture(R.getNameLoc());
} else {
Diag(R.getNameLoc(), diagnostic) << Name;
}
// Do we really want to note all of these?
for (NamedDecl *D : R)
Diag(D->getLocation(), diag::note_dependent_var_use);
// Return true if we are inside a default argument instantiation
// and the found name refers to an instance member function, otherwise
// the function calling DiagnoseEmptyLookup will try to create an
// implicit member call and this is wrong for default argument.
if (isDefaultArgument && ((*R.begin())->isCXXInstanceMember())) {
Diag(R.getNameLoc(), diag::err_member_call_without_object);
return true;
}
// Tell the callee to try to recover.
return false;
}
R.clear();
}
// In Microsoft mode, if we are performing lookup from within a friend
// function definition declared at class scope then we must set
// DC to the lexical parent to be able to search into the parent
// class.
if (getLangOpts().MSVCCompat && isa<FunctionDecl>(DC) &&
cast<FunctionDecl>(DC)->getFriendObjectKind() &&
DC->getLexicalParent()->isRecord())
DC = DC->getLexicalParent();
else
DC = DC->getParent();
}
// We didn't find anything, so try to correct for a typo.
TypoCorrection Corrected;
if (S && Out) {
SourceLocation TypoLoc = R.getNameLoc();
assert(!ExplicitTemplateArgs &&
"Diagnosing an empty lookup with explicit template args!");
*Out = CorrectTypoDelayed(
R.getLookupNameInfo(), R.getLookupKind(), S, &SS, std::move(CCC),
[=](const TypoCorrection &TC) {
emitEmptyLookupTypoDiagnostic(TC, *this, SS, Name, TypoLoc, Args,
diagnostic, diagnostic_suggest);
},
nullptr, CTK_ErrorRecovery);
if (*Out)
return true;
} else if (S && (Corrected =
CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), S,
&SS, std::move(CCC), CTK_ErrorRecovery))) {
std::string CorrectedStr(Corrected.getAsString(getLangOpts()));
bool DroppedSpecifier =
Corrected.WillReplaceSpecifier() && Name.getAsString() == CorrectedStr;
R.setLookupName(Corrected.getCorrection());
bool AcceptableWithRecovery = false;
bool AcceptableWithoutRecovery = false;
NamedDecl *ND = Corrected.getFoundDecl();
if (ND) {
if (Corrected.isOverloaded()) {
OverloadCandidateSet OCS(R.getNameLoc(),
OverloadCandidateSet::CSK_Normal);
OverloadCandidateSet::iterator Best;
for (NamedDecl *CD : Corrected) {
if (FunctionTemplateDecl *FTD =
dyn_cast<FunctionTemplateDecl>(CD))
AddTemplateOverloadCandidate(
FTD, DeclAccessPair::make(FTD, AS_none), ExplicitTemplateArgs,
Args, OCS);
else if (FunctionDecl *FD = dyn_cast<FunctionDecl>(CD))
if (!ExplicitTemplateArgs || ExplicitTemplateArgs->size() == 0)
AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none),
Args, OCS);
}
switch (OCS.BestViableFunction(*this, R.getNameLoc(), Best)) {
case OR_Success:
ND = Best->FoundDecl;
Corrected.setCorrectionDecl(ND);
break;
default:
// FIXME: Arbitrarily pick the first declaration for the note.
Corrected.setCorrectionDecl(ND);
break;
}
}
R.addDecl(ND);
if (getLangOpts().CPlusPlus && ND->isCXXClassMember()) {
CXXRecordDecl *Record = nullptr;
if (Corrected.getCorrectionSpecifier()) {
const Type *Ty = Corrected.getCorrectionSpecifier()->getAsType();
Record = Ty->getAsCXXRecordDecl();
}
if (!Record)
Record = cast<CXXRecordDecl>(
ND->getDeclContext()->getRedeclContext());
R.setNamingClass(Record);
}
auto *UnderlyingND = ND->getUnderlyingDecl();
AcceptableWithRecovery = isa<ValueDecl>(UnderlyingND) ||
isa<FunctionTemplateDecl>(UnderlyingND);
// FIXME: If we ended up with a typo for a type name or
// Objective-C class name, we're in trouble because the parser
// is in the wrong place to recover. Suggest the typo
// correction, but don't make it a fix-it since we're not going
// to recover well anyway.
AcceptableWithoutRecovery =
isa<TypeDecl>(UnderlyingND) || isa<ObjCInterfaceDecl>(UnderlyingND);
} else {
// FIXME: We found a keyword. Suggest it, but don't provide a fix-it
// because we aren't able to recover.
AcceptableWithoutRecovery = true;
}
if (AcceptableWithRecovery || AcceptableWithoutRecovery) {
unsigned NoteID = Corrected.getCorrectionDeclAs<ImplicitParamDecl>()
? diag::note_implicit_param_decl
: diag::note_previous_decl;
if (SS.isEmpty())
diagnoseTypo(Corrected, PDiag(diagnostic_suggest) << Name,
PDiag(NoteID), AcceptableWithRecovery);
else
diagnoseTypo(Corrected, PDiag(diag::err_no_member_suggest)
<< Name << computeDeclContext(SS, false)
<< DroppedSpecifier << SS.getRange(),
PDiag(NoteID), AcceptableWithRecovery);
// Tell the callee whether to try to recover.
return !AcceptableWithRecovery;
}
}
R.clear();
// Emit a special diagnostic for failed member lookups.
// FIXME: computing the declaration context might fail here (?)
if (!SS.isEmpty()) {
Diag(R.getNameLoc(), diag::err_no_member)
<< Name << computeDeclContext(SS, false)
<< SS.getRange();
return true;
}
// Give up, we can't recover.
Diag(R.getNameLoc(), diagnostic) << Name;
return true;
}
/// In Microsoft mode, if we are inside a template class whose parent class has
/// dependent base classes, and we can't resolve an unqualified identifier, then
/// assume the identifier is a member of a dependent base class. We can only
/// recover successfully in static methods, instance methods, and other contexts
/// where 'this' is available. This doesn't precisely match MSVC's
/// instantiation model, but it's close enough.
static Expr *
recoverFromMSUnqualifiedLookup(Sema &S, ASTContext &Context,
DeclarationNameInfo &NameInfo,
SourceLocation TemplateKWLoc,
const TemplateArgumentListInfo *TemplateArgs) {
// Only try to recover from lookup into dependent bases in static methods or
// contexts where 'this' is available.
QualType ThisType = S.getCurrentThisType();
const CXXRecordDecl *RD = nullptr;
if (!ThisType.isNull())
RD = ThisType->getPointeeType()->getAsCXXRecordDecl();
else if (auto *MD = dyn_cast<CXXMethodDecl>(S.CurContext))
RD = MD->getParent();
if (!RD || !RD->hasAnyDependentBases())
return nullptr;
// Diagnose this as unqualified lookup into a dependent base class. If 'this'
// is available, suggest inserting 'this->' as a fixit.
SourceLocation Loc = NameInfo.getLoc();
auto DB = S.Diag(Loc, diag::ext_undeclared_unqual_id_with_dependent_base);
DB << NameInfo.getName() << RD;
if (!ThisType.isNull()) {
DB << FixItHint::CreateInsertion(Loc, "this->");
return CXXDependentScopeMemberExpr::Create(
Context, /*This=*/nullptr, ThisType, /*IsArrow=*/true,
/*Op=*/SourceLocation(), NestedNameSpecifierLoc(), TemplateKWLoc,
/*FirstQualifierInScope=*/nullptr, NameInfo, TemplateArgs);
}
// Synthesize a fake NNS that points to the derived class. This will
// perform name lookup during template instantiation.
CXXScopeSpec SS;
auto *NNS =
NestedNameSpecifier::Create(Context, nullptr, true, RD->getTypeForDecl());
SS.MakeTrivial(Context, NNS, SourceRange(Loc, Loc));
return DependentScopeDeclRefExpr::Create(
Context, SS.getWithLocInContext(Context), TemplateKWLoc, NameInfo,
TemplateArgs);
}
ExprResult
Sema::ActOnIdExpression(Scope *S, CXXScopeSpec &SS,
SourceLocation TemplateKWLoc, UnqualifiedId &Id,
bool HasTrailingLParen, bool IsAddressOfOperand,
std::unique_ptr<CorrectionCandidateCallback> CCC,
bool IsInlineAsmIdentifier, Token *KeywordReplacement) {
assert(!(IsAddressOfOperand && HasTrailingLParen) &&
"cannot be direct & operand and have a trailing lparen");
if (SS.isInvalid())
return ExprError();
TemplateArgumentListInfo TemplateArgsBuffer;
// Decompose the UnqualifiedId into the following data.
DeclarationNameInfo NameInfo;
const TemplateArgumentListInfo *TemplateArgs;
DecomposeUnqualifiedId(Id, TemplateArgsBuffer, NameInfo, TemplateArgs);
DeclarationName Name = NameInfo.getName();
IdentifierInfo *II = Name.getAsIdentifierInfo();
SourceLocation NameLoc = NameInfo.getLoc();
if (II && II->isEditorPlaceholder()) {
// FIXME: When typed placeholders are supported we can create a typed
// placeholder expression node.
return ExprError();
}
// C++ [temp.dep.expr]p3:
// An id-expression is type-dependent if it contains:
// -- an identifier that was declared with a dependent type,
// (note: handled after lookup)
// -- a template-id that is dependent,
// (note: handled in BuildTemplateIdExpr)
// -- a conversion-function-id that specifies a dependent type,
// -- a nested-name-specifier that contains a class-name that
// names a dependent type.
// Determine whether this is a member of an unknown specialization;
// we need to handle these differently.
bool DependentID = false;
if (Name.getNameKind() == DeclarationName::CXXConversionFunctionName &&
Name.getCXXNameType()->isDependentType()) {
DependentID = true;
} else if (SS.isSet()) {
if (DeclContext *DC = computeDeclContext(SS, false)) {
if (RequireCompleteDeclContext(SS, DC))
return ExprError();
} else {
DependentID = true;
}
}
if (DependentID)
return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
IsAddressOfOperand, TemplateArgs);
// Perform the required lookup.
LookupResult R(*this, NameInfo,
(Id.getKind() == UnqualifiedIdKind::IK_ImplicitSelfParam)
? LookupObjCImplicitSelfParam
: LookupOrdinaryName);
if (TemplateKWLoc.isValid() || TemplateArgs) {
// Lookup the template name again to correctly establish the context in
// which it was found. This is really unfortunate as we already did the
// lookup to determine that it was a template name in the first place. If
// this becomes a performance hit, we can work harder to preserve those
// results until we get here but it's likely not worth it.
bool MemberOfUnknownSpecialization;
if (LookupTemplateName(R, S, SS, QualType(), /*EnteringContext=*/false,
MemberOfUnknownSpecialization, TemplateKWLoc))
return ExprError();
if (MemberOfUnknownSpecialization ||
(R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation))
return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
IsAddressOfOperand, TemplateArgs);
} else {
bool IvarLookupFollowUp = II && !SS.isSet() && getCurMethodDecl();
LookupParsedName(R, S, &SS, !IvarLookupFollowUp);
// If the result might be in a dependent base class, this is a dependent
// id-expression.
if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)
return ActOnDependentIdExpression(SS, TemplateKWLoc, NameInfo,
IsAddressOfOperand, TemplateArgs);
// If this reference is in an Objective-C method, then we need to do
// some special Objective-C lookup, too.
if (IvarLookupFollowUp) {
ExprResult E(LookupInObjCMethod(R, S, II, true));
if (E.isInvalid())
return ExprError();
if (Expr *Ex = E.getAs<Expr>())
return Ex;
}
}
if (R.isAmbiguous())
return ExprError();
// This could be an implicitly declared function reference (legal in C90,
// extension in C99, forbidden in C++).
if (R.empty() && HasTrailingLParen && II && !getLangOpts().CPlusPlus) {
NamedDecl *D = ImplicitlyDefineFunction(NameLoc, *II, S);
if (D) R.addDecl(D);
}
// Determine whether this name might be a candidate for
// argument-dependent lookup.
bool ADL = UseArgumentDependentLookup(SS, R, HasTrailingLParen);
if (R.empty() && !ADL) {
if (SS.isEmpty() && getLangOpts().MSVCCompat) {
if (Expr *E = recoverFromMSUnqualifiedLookup(*this, Context, NameInfo,
TemplateKWLoc, TemplateArgs))
return E;
}
// Don't diagnose an empty lookup for inline assembly.
if (IsInlineAsmIdentifier)
return ExprError();
// If this name wasn't predeclared and if this is not a function
// call, diagnose the problem.
TypoExpr *TE = nullptr;
auto DefaultValidator = llvm::make_unique<CorrectionCandidateCallback>(
II, SS.isValid() ? SS.getScopeRep() : nullptr);
DefaultValidator->IsAddressOfOperand = IsAddressOfOperand;
assert((!CCC || CCC->IsAddressOfOperand == IsAddressOfOperand) &&
"Typo correction callback misconfigured");
if (CCC) {
// Make sure the callback knows what the typo being diagnosed is.
CCC->setTypoName(II);
if (SS.isValid())
CCC->setTypoNNS(SS.getScopeRep());
}
// FIXME: DiagnoseEmptyLookup produces bad diagnostics if we're looking for
// a template name, but we happen to have always already looked up the name
// before we get here if it must be a template name.
if (DiagnoseEmptyLookup(S, SS, R,
CCC ? std::move(CCC) : std::move(DefaultValidator),
nullptr, None, &TE)) {
if (TE && KeywordReplacement) {
auto &State = getTypoExprState(TE);
auto BestTC = State.Consumer->getNextCorrection();
if (BestTC.isKeyword()) {
auto *II = BestTC.getCorrectionAsIdentifierInfo();
if (State.DiagHandler)
State.DiagHandler(BestTC);
KeywordReplacement->startToken();
KeywordReplacement->setKind(II->getTokenID());
KeywordReplacement->setIdentifierInfo(II);
KeywordReplacement->setLocation(BestTC.getCorrectionRange().getBegin());
// Clean up the state associated with the TypoExpr, since it has
// now been diagnosed (without a call to CorrectDelayedTyposInExpr).
clearDelayedTypo(TE);
// Signal that a correction to a keyword was performed by returning a
// valid-but-null ExprResult.
return (Expr*)nullptr;
}
State.Consumer->resetCorrectionStream();
}
return TE ? TE : ExprError();
}
assert(!R.empty() &&
"DiagnoseEmptyLookup returned false but added no results");
// If we found an Objective-C instance variable, let
// LookupInObjCMethod build the appropriate expression to
// reference the ivar.
if (ObjCIvarDecl *Ivar = R.getAsSingle<ObjCIvarDecl>()) {
R.clear();
ExprResult E(LookupInObjCMethod(R, S, Ivar->getIdentifier()));
// In a hopelessly buggy code, Objective-C instance variable
// lookup fails and no expression will be built to reference it.
if (!E.isInvalid() && !E.get())
return ExprError();
return E;
}
}
// This is guaranteed from this point on.
assert(!R.empty() || ADL);
// Check whether this might be a C++ implicit instance member access.
// C++ [class.mfct.non-static]p3:
// When an id-expression that is not part of a class member access
// syntax and not used to form a pointer to member is used in the
// body of a non-static member function of class X, if name lookup
// resolves the name in the id-expression to a non-static non-type
// member of some class C, the id-expression is transformed into a
// class member access expression using (*this) as the
// postfix-expression to the left of the . operator.
//
// But we don't actually need to do this for '&' operands if R
// resolved to a function or overloaded function set, because the
// expression is ill-formed if it actually works out to be a
// non-static member function:
//
// C++ [expr.ref]p4:
// Otherwise, if E1.E2 refers to a non-static member function. . .
// [t]he expression can be used only as the left-hand operand of a
// member function call.
//
// There are other safeguards against such uses, but it's important
// to get this right here so that we don't end up making a
// spuriously dependent expression if we're inside a dependent
// instance method.
if (!R.empty() && (*R.begin())->isCXXClassMember()) {
bool MightBeImplicitMember;
if (!IsAddressOfOperand)
MightBeImplicitMember = true;
else if (!SS.isEmpty())
MightBeImplicitMember = false;
else if (R.isOverloadedResult())
MightBeImplicitMember = false;
else if (R.isUnresolvableResult())
MightBeImplicitMember = true;
else
MightBeImplicitMember = isa<FieldDecl>(R.getFoundDecl()) ||
isa<IndirectFieldDecl>(R.getFoundDecl()) ||
isa<MSPropertyDecl>(R.getFoundDecl());
if (MightBeImplicitMember)
return BuildPossibleImplicitMemberExpr(SS, TemplateKWLoc,
R, TemplateArgs, S);
}
if (TemplateArgs || TemplateKWLoc.isValid()) {
// In C++1y, if this is a variable template id, then check it
// in BuildTemplateIdExpr().
// The single lookup result must be a variable template declaration.
if (Id.getKind() == UnqualifiedIdKind::IK_TemplateId && Id.TemplateId &&
Id.TemplateId->Kind == TNK_Var_template) {
assert(R.getAsSingle<VarTemplateDecl>() &&
"There should only be one declaration found.");
}
return BuildTemplateIdExpr(SS, TemplateKWLoc, R, ADL, TemplateArgs);
}
return BuildDeclarationNameExpr(SS, R, ADL);
}
/// BuildQualifiedDeclarationNameExpr - Build a C++ qualified
/// declaration name, generally during template instantiation.
/// There's a large number of things which don't need to be done along
/// this path.
ExprResult Sema::BuildQualifiedDeclarationNameExpr(
CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo,
bool IsAddressOfOperand, const Scope *S, TypeSourceInfo **RecoveryTSI) {
DeclContext *DC = computeDeclContext(SS, false);
if (!DC)
return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
NameInfo, /*TemplateArgs=*/nullptr);
if (RequireCompleteDeclContext(SS, DC))
return ExprError();
LookupResult R(*this, NameInfo, LookupOrdinaryName);
LookupQualifiedName(R, DC);
if (R.isAmbiguous())
return ExprError();
if (R.getResultKind() == LookupResult::NotFoundInCurrentInstantiation)
return BuildDependentDeclRefExpr(SS, /*TemplateKWLoc=*/SourceLocation(),
NameInfo, /*TemplateArgs=*/nullptr);
if (R.empty()) {
Diag(NameInfo.getLoc(), diag::err_no_member)
<< NameInfo.getName() << DC << SS.getRange();
return ExprError();
}
if (const TypeDecl *TD = R.getAsSingle<TypeDecl>()) {
// Diagnose a missing typename if this resolved unambiguously to a type in
// a dependent context. If we can recover with a type, downgrade this to
// a warning in Microsoft compatibility mode.
unsigned DiagID = diag::err_typename_missing;
if (RecoveryTSI && getLangOpts().MSVCCompat)
DiagID = diag::ext_typename_missing;
SourceLocation Loc = SS.getBeginLoc();
auto D = Diag(Loc, DiagID);
D << SS.getScopeRep() << NameInfo.getName().getAsString()
<< SourceRange(Loc, NameInfo.getEndLoc());
// Don't recover if the caller isn't expecting us to or if we're in a SFINAE
// context.
if (!RecoveryTSI)
return ExprError();
// Only issue the fixit if we're prepared to recover.
D << FixItHint::CreateInsertion(Loc, "typename ");
// Recover by pretending this was an elaborated type.
QualType Ty = Context.getTypeDeclType(TD);
TypeLocBuilder TLB;
TLB.pushTypeSpec(Ty).setNameLoc(NameInfo.getLoc());
QualType ET = getElaboratedType(ETK_None, SS, Ty);
ElaboratedTypeLoc QTL = TLB.push<ElaboratedTypeLoc>(ET);
QTL.setElaboratedKeywordLoc(SourceLocation());
QTL.setQualifierLoc(SS.getWithLocInContext(Context));
*RecoveryTSI = TLB.getTypeSourceInfo(Context, ET);
return ExprEmpty();
}
// Defend against this resolving to an implicit member access. We usually
// won't get here if this might be a legitimate a class member (we end up in
// BuildMemberReferenceExpr instead), but this can be valid if we're forming
// a pointer-to-member or in an unevaluated context in C++11.
if (!R.empty() && (*R.begin())->isCXXClassMember() && !IsAddressOfOperand)
return BuildPossibleImplicitMemberExpr(SS,
/*TemplateKWLoc=*/SourceLocation(),
R, /*TemplateArgs=*/nullptr, S);
return BuildDeclarationNameExpr(SS, R, /* ADL */ false);
}
/// LookupInObjCMethod - The parser has read a name in, and Sema has
/// detected that we're currently inside an ObjC method. Perform some
/// additional lookup.
///
/// Ideally, most of this would be done by lookup, but there's
/// actually quite a lot of extra work involved.
///
/// Returns a null sentinel to indicate trivial success.
ExprResult
Sema::LookupInObjCMethod(LookupResult &Lookup, Scope *S,
IdentifierInfo *II, bool AllowBuiltinCreation) {
SourceLocation Loc = Lookup.getNameLoc();
ObjCMethodDecl *CurMethod = getCurMethodDecl();
// Check for error condition which is already reported.
if (!CurMethod)
return ExprError();
// There are two cases to handle here. 1) scoped lookup could have failed,
// in which case we should look for an ivar. 2) scoped lookup could have
// found a decl, but that decl is outside the current instance method (i.e.
// a global variable). In these two cases, we do a lookup for an ivar with
// this name, if the lookup sucedes, we replace it our current decl.
// If we're in a class method, we don't normally want to look for
// ivars. But if we don't find anything else, and there's an
// ivar, that's an error.
bool IsClassMethod = CurMethod->isClassMethod();
bool LookForIvars;
if (Lookup.empty())
LookForIvars = true;
else if (IsClassMethod)
LookForIvars = false;
else
LookForIvars = (Lookup.isSingleResult() &&
Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod());
ObjCInterfaceDecl *IFace = nullptr;
if (LookForIvars) {
IFace = CurMethod->getClassInterface();
ObjCInterfaceDecl *ClassDeclared;
ObjCIvarDecl *IV = nullptr;
if (IFace && (IV = IFace->lookupInstanceVariable(II, ClassDeclared))) {
// Diagnose using an ivar in a class method.
if (IsClassMethod)
return ExprError(Diag(Loc, diag::err_ivar_use_in_class_method)
<< IV->getDeclName());
// If we're referencing an invalid decl, just return this as a silent
// error node. The error diagnostic was already emitted on the decl.
if (IV->isInvalidDecl())
return ExprError();
// Check if referencing a field with __attribute__((deprecated)).
if (DiagnoseUseOfDecl(IV, Loc))
return ExprError();
// Diagnose the use of an ivar outside of the declaring class.
if (IV->getAccessControl() == ObjCIvarDecl::Private &&
!declaresSameEntity(ClassDeclared, IFace) &&
!getLangOpts().DebuggerSupport)
Diag(Loc, diag::err_private_ivar_access) << IV->getDeclName();
// FIXME: This should use a new expr for a direct reference, don't
// turn this into Self->ivar, just return a BareIVarExpr or something.
IdentifierInfo &II = Context.Idents.get("self");
UnqualifiedId SelfName;
SelfName.setIdentifier(&II, SourceLocation());
SelfName.setKind(UnqualifiedIdKind::IK_ImplicitSelfParam);
CXXScopeSpec SelfScopeSpec;
SourceLocation TemplateKWLoc;
ExprResult SelfExpr = ActOnIdExpression(S, SelfScopeSpec, TemplateKWLoc,
SelfName, false, false);
if (SelfExpr.isInvalid())
return ExprError();
SelfExpr = DefaultLvalueConversion(SelfExpr.get());
if (SelfExpr.isInvalid())
return ExprError();
MarkAnyDeclReferenced(Loc, IV, true);
ObjCMethodFamily MF = CurMethod->getMethodFamily();
if (MF != OMF_init && MF != OMF_dealloc && MF != OMF_finalize &&
!IvarBacksCurrentMethodAccessor(IFace, CurMethod, IV))
Diag(Loc, diag::warn_direct_ivar_access) << IV->getDeclName();
ObjCIvarRefExpr *Result = new (Context)
ObjCIvarRefExpr(IV, IV->getUsageType(SelfExpr.get()->getType()), Loc,
IV->getLocation(), SelfExpr.get(), true, true);
if (IV->getType().getObjCLifetime() == Qualifiers::OCL_Weak) {
if (!isUnevaluatedContext() &&
!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak, Loc))
getCurFunction()->recordUseOfWeak(Result);
}
if (getLangOpts().ObjCAutoRefCount) {
if (CurContext->isClosure())
Diag(Loc, diag::warn_implicitly_retains_self)
<< FixItHint::CreateInsertion(Loc, "self->");
}
return Result;
}
} else if (CurMethod->isInstanceMethod()) {
// We should warn if a local variable hides an ivar.
if (ObjCInterfaceDecl *IFace = CurMethod->getClassInterface()) {
ObjCInterfaceDecl *ClassDeclared;
if (ObjCIvarDecl *IV = IFace->lookupInstanceVariable(II, ClassDeclared)) {
if (IV->getAccessControl() != ObjCIvarDecl::Private ||
declaresSameEntity(IFace, ClassDeclared))
Diag(Loc, diag::warn_ivar_use_hidden) << IV->getDeclName();
}
}
} else if (Lookup.isSingleResult() &&
Lookup.getFoundDecl()->isDefinedOutsideFunctionOrMethod()) {
// If accessing a stand-alone ivar in a class method, this is an error.
if (const ObjCIvarDecl *IV = dyn_cast<ObjCIvarDecl>(Lookup.getFoundDecl()))
return ExprError(Diag(Loc, diag::err_ivar_use_in_class_method)
<< IV->getDeclName());
}
if (Lookup.empty() && II && AllowBuiltinCreation) {
// FIXME. Consolidate this with similar code in LookupName.
if (unsigned BuiltinID = II->getBuiltinID()) {
if (!(getLangOpts().CPlusPlus &&
Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))) {
NamedDecl *D = LazilyCreateBuiltin((IdentifierInfo *)II, BuiltinID,
S, Lookup.isForRedeclaration(),
Lookup.getNameLoc());
if (D) Lookup.addDecl(D);
}
}
}
// Sentinel value saying that we didn't do anything special.
return ExprResult((Expr *)nullptr);
}
/// Cast a base object to a member's actual type.
///
/// Logically this happens in three phases:
///
/// * First we cast from the base type to the naming class.
/// The naming class is the class into which we were looking
/// when we found the member; it's the qualifier type if a
/// qualifier was provided, and otherwise it's the base type.
///
/// * Next we cast from the naming class to the declaring class.
/// If the member we found was brought into a class's scope by
/// a using declaration, this is that class; otherwise it's
/// the class declaring the member.
///
/// * Finally we cast from the declaring class to the "true"
/// declaring class of the member. This conversion does not
/// obey access control.
ExprResult
Sema::PerformObjectMemberConversion(Expr *From,
NestedNameSpecifier *Qualifier,
NamedDecl *FoundDecl,
NamedDecl *Member) {
CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Member->getDeclContext());
if (!RD)
return From;
QualType DestRecordType;
QualType DestType;
QualType FromRecordType;
QualType FromType = From->getType();
bool PointerConversions = false;
if (isa<FieldDecl>(Member)) {
DestRecordType = Context.getCanonicalType(Context.getTypeDeclType(RD));
if (FromType->getAs<PointerType>()) {
DestType = Context.getPointerType(DestRecordType);
FromRecordType = FromType->getPointeeType();
PointerConversions = true;
} else {
DestType = DestRecordType;
FromRecordType = FromType;
}
} else if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Member)) {
if (Method->isStatic())
return From;
DestType = Method->getThisType(Context);
DestRecordType = DestType->getPointeeType();
if (FromType->getAs<PointerType>()) {
FromRecordType = FromType->getPointeeType();
PointerConversions = true;
} else {
FromRecordType = FromType;
DestType = DestRecordType;
}
} else {
// No conversion necessary.
return From;
}
if (DestType->isDependentType() || FromType->isDependentType())
return From;
// If the unqualified types are the same, no conversion is necessary.
if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType))
return From;
SourceRange FromRange = From->getSourceRange();
SourceLocation FromLoc = FromRange.getBegin();
ExprValueKind VK = From->getValueKind();
// C++ [class.member.lookup]p8:
// [...] Ambiguities can often be resolved by qualifying a name with its
// class name.
//
// If the member was a qualified name and the qualified referred to a
// specific base subobject type, we'll cast to that intermediate type
// first and then to the object in which the member is declared. That allows
// one to resolve ambiguities in, e.g., a diamond-shaped hierarchy such as:
//
// class Base { public: int x; };
// class Derived1 : public Base { };
// class Derived2 : public Base { };
// class VeryDerived : public Derived1, public Derived2 { void f(); };
//
// void VeryDerived::f() {
// x = 17; // error: ambiguous base subobjects
// Derived1::x = 17; // okay, pick the Base subobject of Derived1
// }
if (Qualifier && Qualifier->getAsType()) {
QualType QType = QualType(Qualifier->getAsType(), 0);
assert(QType->isRecordType() && "lookup done with non-record type");
QualType QRecordType = QualType(QType->getAs<RecordType>(), 0);
// In C++98, the qualifier type doesn't actually have to be a base
// type of the object type, in which case we just ignore it.
// Otherwise build the appropriate casts.
if (IsDerivedFrom(FromLoc, FromRecordType, QRecordType)) {
CXXCastPath BasePath;
if (CheckDerivedToBaseConversion(FromRecordType, QRecordType,
FromLoc, FromRange, &BasePath))
return ExprError();
if (PointerConversions)
QType = Context.getPointerType(QType);
From = ImpCastExprToType(From, QType, CK_UncheckedDerivedToBase,
VK, &BasePath).get();
FromType = QType;
FromRecordType = QRecordType;
// If the qualifier type was the same as the destination type,
// we're done.
if (Context.hasSameUnqualifiedType(FromRecordType, DestRecordType))
return From;
}
}
bool IgnoreAccess = false;
// If we actually found the member through a using declaration, cast
// down to the using declaration's type.
//
// Pointer equality is fine here because only one declaration of a
// class ever has member declarations.
if (FoundDecl->getDeclContext() != Member->getDeclContext()) {
assert(isa<UsingShadowDecl>(FoundDecl));
QualType URecordType = Context.getTypeDeclType(
cast<CXXRecordDecl>(FoundDecl->getDeclContext()));
// We only need to do this if the naming-class to declaring-class
// conversion is non-trivial.
if (!Context.hasSameUnqualifiedType(FromRecordType, URecordType)) {
assert(IsDerivedFrom(FromLoc, FromRecordType, URecordType));
CXXCastPath BasePath;
if (CheckDerivedToBaseConversion(FromRecordType, URecordType,
FromLoc, FromRange, &BasePath))
return ExprError();
QualType UType = URecordType;
if (PointerConversions)
UType = Context.getPointerType(UType);
From = ImpCastExprToType(From, UType, CK_UncheckedDerivedToBase,
VK, &BasePath).get();
FromType = UType;
FromRecordType = URecordType;
}
// We don't do access control for the conversion from the
// declaring class to the true declaring class.
IgnoreAccess = true;
}
CXXCastPath BasePath;
if (CheckDerivedToBaseConversion(FromRecordType, DestRecordType,
FromLoc, FromRange, &BasePath,
IgnoreAccess))
return ExprError();
return ImpCastExprToType(From, DestType, CK_UncheckedDerivedToBase,
VK, &BasePath);
}
bool Sema::UseArgumentDependentLookup(const CXXScopeSpec &SS,
const LookupResult &R,
bool HasTrailingLParen) {
// Only when used directly as the postfix-expression of a call.
if (!HasTrailingLParen)
return false;
// Never if a scope specifier was provided.
if (SS.isSet())
return false;
// Only in C++ or ObjC++.
if (!getLangOpts().CPlusPlus)
return false;
// Turn off ADL when we find certain kinds of declarations during
// normal lookup:
for (NamedDecl *D : R) {
// C++0x [basic.lookup.argdep]p3:
// -- a declaration of a class member
// Since using decls preserve this property, we check this on the
// original decl.
if (D->isCXXClassMember())
return false;
// C++0x [basic.lookup.argdep]p3:
// -- a block-scope function declaration that is not a
// using-declaration
// NOTE: we also trigger this for function templates (in fact, we
// don't check the decl type at all, since all other decl types
// turn off ADL anyway).
if (isa<UsingShadowDecl>(D))
D = cast<UsingShadowDecl>(D)->getTargetDecl();
else if (D->getLexicalDeclContext()->isFunctionOrMethod())
return false;
// C++0x [basic.lookup.argdep]p3:
// -- a declaration that is neither a function or a function
// template
// And also for builtin functions.
if (isa<FunctionDecl>(D)) {
FunctionDecl *FDecl = cast<FunctionDecl>(D);
// But also builtin functions.
if (FDecl->getBuiltinID() && FDecl->isImplicit())
return false;
} else if (!isa<FunctionTemplateDecl>(D))
return false;
}
return true;
}
/// Diagnoses obvious problems with the use of the given declaration
/// as an expression. This is only actually called for lookups that
/// were not overloaded, and it doesn't promise that the declaration
/// will in fact be used.
static bool CheckDeclInExpr(Sema &S, SourceLocation Loc, NamedDecl *D) {
if (D->isInvalidDecl())
return true;
if (isa<TypedefNameDecl>(D)) {
S.Diag(Loc, diag::err_unexpected_typedef) << D->getDeclName();
return true;
}
if (isa<ObjCInterfaceDecl>(D)) {
S.Diag(Loc, diag::err_unexpected_interface) << D->getDeclName();
return true;
}
if (isa<NamespaceDecl>(D)) {
S.Diag(Loc, diag::err_unexpected_namespace) << D->getDeclName();
return true;
}
return false;
}
// Certain multiversion types should be treated as overloaded even when there is
// only one result.
static bool ShouldLookupResultBeMultiVersionOverload(const LookupResult &R) {
assert(R.isSingleResult() && "Expected only a single result");
const auto *FD = dyn_cast<FunctionDecl>(R.getFoundDecl());
return FD &&
(FD->isCPUDispatchMultiVersion() || FD->isCPUSpecificMultiVersion());
}
ExprResult Sema::BuildDeclarationNameExpr(const CXXScopeSpec &SS,
LookupResult &R, bool NeedsADL,
bool AcceptInvalidDecl) {
// If this is a single, fully-resolved result and we don't need ADL,
// just build an ordinary singleton decl ref.
if (!NeedsADL && R.isSingleResult() &&
!R.getAsSingle<FunctionTemplateDecl>() &&
!ShouldLookupResultBeMultiVersionOverload(R))
return BuildDeclarationNameExpr(SS, R.getLookupNameInfo(), R.getFoundDecl(),
R.getRepresentativeDecl(), nullptr,
AcceptInvalidDecl);
// We only need to check the declaration if there's exactly one
// result, because in the overloaded case the results can only be
// functions and function templates.
if (R.isSingleResult() && !ShouldLookupResultBeMultiVersionOverload(R) &&
CheckDeclInExpr(*this, R.getNameLoc(), R.getFoundDecl()))
return ExprError();
// Otherwise, just build an unresolved lookup expression. Suppress
// any lookup-related diagnostics; we'll hash these out later, when
// we've picked a target.
R.suppressDiagnostics();
UnresolvedLookupExpr *ULE
= UnresolvedLookupExpr::Create(Context, R.getNamingClass(),
SS.getWithLocInContext(Context),
R.getLookupNameInfo(),
NeedsADL, R.isOverloadedResult(),
R.begin(), R.end());
return ULE;
}
static void
diagnoseUncapturableValueReference(Sema &S, SourceLocation loc,
ValueDecl *var, DeclContext *DC);
/// Complete semantic analysis for a reference to the given declaration.
ExprResult Sema::BuildDeclarationNameExpr(
const CXXScopeSpec &SS, const DeclarationNameInfo &NameInfo, NamedDecl *D,
NamedDecl *FoundD, const TemplateArgumentListInfo *TemplateArgs,
bool AcceptInvalidDecl) {
assert(D && "Cannot refer to a NULL declaration");
assert(!isa<FunctionTemplateDecl>(D) &&
"Cannot refer unambiguously to a function template");
SourceLocation Loc = NameInfo.getLoc();
if (CheckDeclInExpr(*this, Loc, D))
return ExprError();
if (TemplateDecl *Template = dyn_cast<TemplateDecl>(D)) {
// Specifically diagnose references to class templates that are missing
// a template argument list.
diagnoseMissingTemplateArguments(TemplateName(Template), Loc);
return ExprError();
}
// Make sure that we're referring to a value.
ValueDecl *VD = dyn_cast<ValueDecl>(D);
if (!VD) {
Diag(Loc, diag::err_ref_non_value)
<< D << SS.getRange();
Diag(D->getLocation(), diag::note_declared_at);
return ExprError();
}
// Check whether this declaration can be used. Note that we suppress
// this check when we're going to perform argument-dependent lookup
// on this function name, because this might not be the function
// that overload resolution actually selects.
if (DiagnoseUseOfDecl(VD, Loc))
return ExprError();
// Only create DeclRefExpr's for valid Decl's.
if (VD->isInvalidDecl() && !AcceptInvalidDecl)
return ExprError();
// Handle members of anonymous structs and unions. If we got here,
// and the reference is to a class member indirect field, then this
// must be the subject of a pointer-to-member expression.
if (IndirectFieldDecl *indirectField = dyn_cast<IndirectFieldDecl>(VD))
if (!indirectField->isCXXClassMember())
return BuildAnonymousStructUnionMemberReference(SS, NameInfo.getLoc(),
indirectField);
{
QualType type = VD->getType();
if (type.isNull())
return ExprError();
if (auto *FPT = type->getAs<FunctionProtoType>()) {
// C++ [except.spec]p17:
// An exception-specification is considered to be needed when:
// - in an expression, the function is the unique lookup result or
// the selected member of a set of overloaded functions.
ResolveExceptionSpec(Loc, FPT);
type = VD->getType();
}
ExprValueKind valueKind = VK_RValue;
switch (D->getKind()) {
// Ignore all the non-ValueDecl kinds.
#define ABSTRACT_DECL(kind)
#define VALUE(type, base)
#define DECL(type, base) \
case Decl::type:
#include "clang/AST/DeclNodes.inc"
llvm_unreachable("invalid value decl kind");
// These shouldn't make it here.
case Decl::ObjCAtDefsField:
case Decl::ObjCIvar:
llvm_unreachable("forming non-member reference to ivar?");
// Enum constants are always r-values and never references.
// Unresolved using declarations are dependent.
case Decl::EnumConstant:
case Decl::UnresolvedUsingValue:
case Decl::OMPDeclareReduction:
valueKind = VK_RValue;
break;
// Fields and indirect fields that got here must be for
// pointer-to-member expressions; we just call them l-values for
// internal consistency, because this subexpression doesn't really
// exist in the high-level semantics.
case Decl::Field:
case Decl::IndirectField:
assert(getLangOpts().CPlusPlus &&
"building reference to field in C?");
// These can't have reference type in well-formed programs, but
// for internal consistency we do this anyway.
type = type.getNonReferenceType();
valueKind = VK_LValue;
break;
// Non-type template parameters are either l-values or r-values
// depending on the type.
case Decl::NonTypeTemplateParm: {
if (const ReferenceType *reftype = type->getAs<ReferenceType>()) {
type = reftype->getPointeeType();
valueKind = VK_LValue; // even if the parameter is an r-value reference
break;
}
// For non-references, we need to strip qualifiers just in case
// the template parameter was declared as 'const int' or whatever.
valueKind = VK_RValue;
type = type.getUnqualifiedType();
break;
}
case Decl::Var:
case Decl::VarTemplateSpecialization:
case Decl::VarTemplatePartialSpecialization:
case Decl::Decomposition:
case Decl::OMPCapturedExpr:
// In C, "extern void blah;" is valid and is an r-value.
if (!getLangOpts().CPlusPlus &&
!type.hasQualifiers() &&
type->isVoidType()) {
valueKind = VK_RValue;
break;
}
LLVM_FALLTHROUGH;
case Decl::ImplicitParam:
case Decl::ParmVar: {
// These are always l-values.
valueKind = VK_LValue;
type = type.getNonReferenceType();
// FIXME: Does the addition of const really only apply in
// potentially-evaluated contexts? Since the variable isn't actually
// captured in an unevaluated context, it seems that the answer is no.
if (!isUnevaluatedContext()) {
QualType CapturedType = getCapturedDeclRefType(cast<VarDecl>(VD), Loc);
if (!CapturedType.isNull())
type = CapturedType;
}
break;
}
case Decl::Binding: {
// These are always lvalues.
valueKind = VK_LValue;
type = type.getNonReferenceType();
// FIXME: Support lambda-capture of BindingDecls, once CWG actually
// decides how that's supposed to work.
auto *BD = cast<BindingDecl>(VD);
if (BD->getDeclContext()->isFunctionOrMethod() &&
BD->getDeclContext() != CurContext)
diagnoseUncapturableValueReference(*this, Loc, BD, CurContext);
break;
}
case Decl::Function: {
if (unsigned BID = cast<FunctionDecl>(VD)->getBuiltinID()) {
if (!Context.BuiltinInfo.isPredefinedLibFunction(BID)) {
type = Context.BuiltinFnTy;
valueKind = VK_RValue;
break;
}
}
const FunctionType *fty = type->castAs<FunctionType>();
// If we're referring to a function with an __unknown_anytype
// result type, make the entire expression __unknown_anytype.
if (fty->getReturnType() == Context.UnknownAnyTy) {
type = Context.UnknownAnyTy;
valueKind = VK_RValue;
break;
}
// Functions are l-values in C++.
if (getLangOpts().CPlusPlus) {
valueKind = VK_LValue;
break;
}
// C99 DR 316 says that, if a function type comes from a
// function definition (without a prototype), that type is only
// used for checking compatibility. Therefore, when referencing
// the function, we pretend that we don't have the full function
// type.
if (!cast<FunctionDecl>(VD)->hasPrototype() &&
isa<FunctionProtoType>(fty))
type = Context.getFunctionNoProtoType(fty->getReturnType(),
fty->getExtInfo());
// Functions are r-values in C.
valueKind = VK_RValue;
break;
}
case Decl::CXXDeductionGuide:
llvm_unreachable("building reference to deduction guide");
case Decl::MSProperty:
valueKind = VK_LValue;
break;
case Decl::CXXMethod:
// If we're referring to a method with an __unknown_anytype
// result type, make the entire expression __unknown_anytype.
// This should only be possible with a type written directly.
if (const FunctionProtoType *proto
= dyn_cast<FunctionProtoType>(VD->getType()))
if (proto->getReturnType() == Context.UnknownAnyTy) {
type = Context.UnknownAnyTy;
valueKind = VK_RValue;
break;
}
// C++ methods are l-values if static, r-values if non-static.
if (cast<CXXMethodDecl>(VD)->isStatic()) {
valueKind = VK_LValue;
break;
}
LLVM_FALLTHROUGH;
case Decl::CXXConversion:
case Decl::CXXDestructor:
case Decl::CXXConstructor:
valueKind = VK_RValue;
break;
}
return BuildDeclRefExpr(VD, type, valueKind, NameInfo, &SS, FoundD,
TemplateArgs);
}
}
static void ConvertUTF8ToWideString(unsigned CharByteWidth, StringRef Source,
SmallString<32> &Target) {
Target.resize(CharByteWidth * (Source.size() + 1));
char *ResultPtr = &Target[0];
const llvm::UTF8 *ErrorPtr;
bool success =
llvm::ConvertUTF8toWide(CharByteWidth, Source, ResultPtr, ErrorPtr);
(void)success;
assert(success);
Target.resize(ResultPtr - &Target[0]);
}
ExprResult Sema::BuildPredefinedExpr(SourceLocation Loc,
PredefinedExpr::IdentType IT) {
// Pick the current block, lambda, captured statement or function.
Decl *currentDecl = nullptr;
if (const BlockScopeInfo *BSI = getCurBlock())
currentDecl = BSI->TheDecl;
else if (const LambdaScopeInfo *LSI = getCurLambda())
currentDecl = LSI->CallOperator;
else if (const CapturedRegionScopeInfo *CSI = getCurCapturedRegion())
currentDecl = CSI->TheCapturedDecl;
else
currentDecl = getCurFunctionOrMethodDecl();
if (!currentDecl) {
Diag(Loc, diag::ext_predef_outside_function);
currentDecl = Context.getTranslationUnitDecl();
}
QualType ResTy;
StringLiteral *SL = nullptr;
if (cast<DeclContext>(currentDecl)->isDependentContext())
ResTy = Context.DependentTy;
else {
// Pre-defined identifiers are of type char[x], where x is the length of
// the string.
auto Str = PredefinedExpr::ComputeName(IT, currentDecl);
unsigned Length = Str.length();
llvm::APInt LengthI(32, Length + 1);
if (IT == PredefinedExpr::LFunction || IT == PredefinedExpr::LFuncSig) {
ResTy =
Context.adjustStringLiteralBaseType(Context.WideCharTy.withConst());
SmallString<32> RawChars;
ConvertUTF8ToWideString(Context.getTypeSizeInChars(ResTy).getQuantity(),
Str, RawChars);
ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal,
/*IndexTypeQuals*/ 0);
SL = StringLiteral::Create(Context, RawChars, StringLiteral::Wide,
/*Pascal*/ false, ResTy, Loc);
} else {
ResTy = Context.adjustStringLiteralBaseType(Context.CharTy.withConst());
ResTy = Context.getConstantArrayType(ResTy, LengthI, ArrayType::Normal,
/*IndexTypeQuals*/ 0);
SL = StringLiteral::Create(Context, Str, StringLiteral::Ascii,
/*Pascal*/ false, ResTy, Loc);
}
}
return new (Context) PredefinedExpr(Loc, ResTy, IT, SL);
}
ExprResult Sema::ActOnPredefinedExpr(SourceLocation Loc, tok::TokenKind Kind) {
PredefinedExpr::IdentType IT;
switch (Kind) {
default: llvm_unreachable("Unknown simple primary expr!");
case tok::kw___func__: IT = PredefinedExpr::Func; break; // [C99 6.4.2.2]
case tok::kw___FUNCTION__: IT = PredefinedExpr::Function; break;
case tok::kw___FUNCDNAME__: IT = PredefinedExpr::FuncDName; break; // [MS]
case tok::kw___FUNCSIG__: IT = PredefinedExpr::FuncSig; break; // [MS]
case tok::kw_L__FUNCTION__: IT = PredefinedExpr::LFunction; break; // [MS]
case tok::kw_L__FUNCSIG__: IT = PredefinedExpr::LFuncSig; break; // [MS]
case tok::kw___PRETTY_FUNCTION__: IT = PredefinedExpr::PrettyFunction; break;
}
return BuildPredefinedExpr(Loc, IT);
}
ExprResult Sema::ActOnCharacterConstant(const Token &Tok, Scope *UDLScope) {
SmallString<16> CharBuffer;
bool Invalid = false;
StringRef ThisTok = PP.getSpelling(Tok, CharBuffer, &Invalid);
if (Invalid)
return ExprError();
CharLiteralParser Literal(ThisTok.begin(), ThisTok.end(), Tok.getLocation(),
PP, Tok.getKind());
if (Literal.hadError())
return ExprError();
QualType Ty;
if (Literal.isWide())
Ty = Context.WideCharTy; // L'x' -> wchar_t in C and C++.
else if (Literal.isUTF8() && getLangOpts().Char8)
Ty = Context.Char8Ty; // u8'x' -> char8_t when it exists.
else if (Literal.isUTF16())
Ty = Context.Char16Ty; // u'x' -> char16_t in C11 and C++11.
else if (Literal.isUTF32())
Ty = Context.Char32Ty; // U'x' -> char32_t in C11 and C++11.
else if (!getLangOpts().CPlusPlus || Literal.isMultiChar())
Ty = Context.IntTy; // 'x' -> int in C, 'wxyz' -> int in C++.
else
Ty = Context.CharTy; // 'x' -> char in C++
CharacterLiteral::CharacterKind Kind = CharacterLiteral::Ascii;
if (Literal.isWide())
Kind = CharacterLiteral::Wide;
else if (Literal.isUTF16())
Kind = CharacterLiteral::UTF16;
else if (Literal.isUTF32())
Kind = CharacterLiteral::UTF32;
else if (Literal.isUTF8())
Kind = CharacterLiteral::UTF8;
Expr *Lit = new (Context) CharacterLiteral(Literal.getValue(), Kind, Ty,
Tok.getLocation());
if (Literal.getUDSuffix().empty())
return Lit;
// We're building a user-defined literal.
IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix());
SourceLocation UDSuffixLoc =
getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset());
// Make sure we're allowed user-defined literals here.
if (!UDLScope)
return ExprError(Diag(UDSuffixLoc, diag::err_invalid_character_udl));
// C++11 [lex.ext]p6: The literal L is treated as a call of the form
// operator "" X (ch)
return BuildCookedLiteralOperatorCall(*this, UDLScope, UDSuffix, UDSuffixLoc,
Lit, Tok.getLocation());
}
ExprResult Sema::ActOnIntegerConstant(SourceLocation Loc, uint64_t Val) {
unsigned IntSize = Context.getTargetInfo().getIntWidth();
return IntegerLiteral::Create(Context, llvm::APInt(IntSize, Val),
Context.IntTy, Loc);
}
static Expr *BuildFloatingLiteral(Sema &S, NumericLiteralParser &Literal,
QualType Ty, SourceLocation Loc) {
const llvm::fltSemantics &Format = S.Context.getFloatTypeSemantics(Ty);
using llvm::APFloat;
APFloat Val(Format);
APFloat::opStatus result = Literal.GetFloatValue(Val);
// Overflow is always an error, but underflow is only an error if
// we underflowed to zero (APFloat reports denormals as underflow).
if ((result & APFloat::opOverflow) ||
((result & APFloat::opUnderflow) && Val.isZero())) {
unsigned diagnostic;
SmallString<20> buffer;
if (result & APFloat::opOverflow) {
diagnostic = diag::warn_float_overflow;
APFloat::getLargest(Format).toString(buffer);
} else {
diagnostic = diag::warn_float_underflow;
APFloat::getSmallest(Format).toString(buffer);
}
S.Diag(Loc, diagnostic)
<< Ty
<< StringRef(buffer.data(), buffer.size());
}
bool isExact = (result == APFloat::opOK);
return FloatingLiteral::Create(S.Context, Val, isExact, Ty, Loc);
}
bool Sema::CheckLoopHintExpr(Expr *E, SourceLocation Loc) {
assert(E && "Invalid expression");
if (E->isValueDependent())
return false;
QualType QT = E->getType();
if (!QT->isIntegerType() || QT->isBooleanType() || QT->isCharType()) {
Diag(E->getExprLoc(), diag::err_pragma_loop_invalid_argument_type) << QT;
return true;
}
llvm::APSInt ValueAPS;
ExprResult R = VerifyIntegerConstantExpression(E, &ValueAPS);
if (R.isInvalid())
return true;
bool ValueIsPositive = ValueAPS.isStrictlyPositive();
if (!ValueIsPositive || ValueAPS.getActiveBits() > 31) {
Diag(E->getExprLoc(), diag::err_pragma_loop_invalid_argument_value)
<< ValueAPS.toString(10) << ValueIsPositive;
return true;
}
return false;
}
ExprResult Sema::ActOnNumericConstant(const Token &Tok, Scope *UDLScope) {
// Fast path for a single digit (which is quite common). A single digit
// cannot have a trigraph, escaped newline, radix prefix, or suffix.
if (Tok.getLength() == 1) {
const char Val = PP.getSpellingOfSingleCharacterNumericConstant(Tok);
return ActOnIntegerConstant(Tok.getLocation(), Val-'0');
}
SmallString<128> SpellingBuffer;
// NumericLiteralParser wants to overread by one character. Add padding to
// the buffer in case the token is copied to the buffer. If getSpelling()
// returns a StringRef to the memory buffer, it should have a null char at
// the EOF, so it is also safe.
SpellingBuffer.resize(Tok.getLength() + 1);
// Get the spelling of the token, which eliminates trigraphs, etc.
bool Invalid = false;
StringRef TokSpelling = PP.getSpelling(Tok, SpellingBuffer, &Invalid);
if (Invalid)
return ExprError();
NumericLiteralParser Literal(TokSpelling, Tok.getLocation(), PP);
if (Literal.hadError)
return ExprError();
if (Literal.hasUDSuffix()) {
// We're building a user-defined literal.
IdentifierInfo *UDSuffix = &Context.Idents.get(Literal.getUDSuffix());
SourceLocation UDSuffixLoc =
getUDSuffixLoc(*this, Tok.getLocation(), Literal.getUDSuffixOffset());
// Make sure we're allowed user-defined literals here.
if (!UDLScope)
return ExprError(Diag(UDSuffixLoc, diag::err_invalid_numeric_udl));
QualType CookedTy;
if (Literal.isFloatingLiteral()) {
// C++11 [lex.ext]p4: If S contains a literal operator with parameter type
// long double, the literal is treated as a call of the form
// operator "" X (f L)
CookedTy = Context.LongDoubleTy;
} else {
// C++11 [lex.ext]p3: If S contains a literal operator with parameter type
// unsigned long long, the literal is treated as a call of the form
// operator "" X (n ULL)
CookedTy = Context.UnsignedLongLongTy;
}
DeclarationName OpName =
Context.DeclarationNames.getCXXLiteralOperatorName(UDSuffix);
DeclarationNameInfo OpNameInfo(OpName, UDSuffixLoc);
OpNameInfo.setCXXLiteralOperatorNameLoc(UDSuffixLoc);
SourceLocation TokLoc = Tok.getLocation();
// Perform literal operator lookup to determine if we're building a raw
// literal or a cooked one.
LookupResult R(*this, OpName, UDSuffixLoc, LookupOrdinaryName);
switch (LookupLiteralOperator(UDLScope, R, CookedTy,
/*AllowRaw*/ true, /*AllowTemplate*/ true,
/*AllowStringTemplate*/ false,
/*DiagnoseMissing*/ !Literal.isImaginary)) {
case LOLR_ErrorNoDiagnostic:
// Lookup failure for imaginary constants isn't fatal, there's still the
// GNU extension producing _Complex types.
break;
case LOLR_Error:
return ExprError();
case LOLR_Cooked: {
Expr *Lit;
if (Literal.isFloatingLiteral()) {
Lit = BuildFloatingLiteral(*this, Literal, CookedTy, Tok.getLocation());
} else {
llvm::APInt ResultVal(Context.getTargetInfo().getLongLongWidth(), 0);
if (Literal.GetIntegerValue(ResultVal))
Diag(Tok.getLocation(), diag::err_integer_literal_too_large)
<< /* Unsigned */ 1;
Lit = IntegerLiteral::Create(Context, ResultVal, CookedTy,
Tok.getLocation());
}
return BuildLiteralOperatorCall(R, OpNameInfo, Lit, TokLoc);
}
case LOLR_Raw: {
// C++11 [lit.ext]p3, p4: If S contains a raw literal operator, the
// literal is treated as a call of the form
// operator "" X ("n")
unsigned Length = Literal.getUDSuffixOffset();
QualType StrTy = Context.getConstantArrayType(
Context.adjustStringLiteralBaseType(Context.CharTy.withConst()),
llvm::APInt(32, Length + 1), ArrayType::Normal, 0);
Expr *Lit = StringLiteral::Create(
Context, StringRef(TokSpelling.data(), Length), StringLiteral::Ascii,
/*Pascal*/false, StrTy, &TokLoc, 1);
return BuildLiteralOperatorCall(R, OpNameInfo, Lit, TokLoc);
}
case LOLR_Template: {
// C++11 [lit.ext]p3, p4: Otherwise (S contains a literal operator
// template), L is treated as a call fo the form
// operator "" X <'c1', 'c2', ... 'ck'>()
// where n is the source character sequence c1 c2 ... ck.
TemplateArgumentListInfo ExplicitArgs;
unsigned CharBits = Context.getIntWidth(Context.CharTy);
bool CharIsUnsigned = Context.CharTy->isUnsignedIntegerType();
llvm::APSInt Value(CharBits, CharIsUnsigned);
for (unsigned I = 0, N = Literal.getUDSuffixOffset(); I != N; ++I) {
Value = TokSpelling[I];
TemplateArgument Arg(Context, Value, Context.CharTy);
TemplateArgumentLocInfo ArgInfo;
ExplicitArgs.addArgument(TemplateArgumentLoc(Arg, ArgInfo));
}
return BuildLiteralOperatorCall(R, OpNameInfo, None, TokLoc,
&ExplicitArgs);
}
case LOLR_StringTemplate:
llvm_unreachable("unexpected literal operator lookup result");
}
}
Expr *Res;
if (Literal.isFixedPointLiteral()) {
QualType Ty;
if (Literal.isAccum) {
if (Literal.isHalf) {
Ty = Context.ShortAccumTy;
} else if (Literal.isLong) {
Ty = Context.LongAccumTy;
} else {
Ty = Context.AccumTy;
}
} else if (Literal.isFract) {
if (Literal.isHalf) {
Ty = Context.ShortFractTy;
} else if (Literal.isLong) {
Ty = Context.LongFractTy;
} else {
Ty = Context.FractTy;
}
}
if (Literal.isUnsigned) Ty = Context.getCorrespondingUnsignedType(Ty);
bool isSigned = !Literal.isUnsigned;
unsigned scale = Context.getFixedPointScale(Ty);
unsigned ibits = Context.getFixedPointIBits(Ty);
unsigned bit_width = Context.getTypeInfo(Ty).Width;
llvm::APInt Val(bit_width, 0, isSigned);
bool Overflowed = Literal.GetFixedPointValue(Val, scale);
// Do not use bit_width since some types may have padding like _Fract or
// unsigned _Accums if PaddingOnUnsignedFixedPoint is set.
auto MaxVal = llvm::APInt::getMaxValue(ibits + scale).zextOrSelf(bit_width);
if (Literal.isFract && Val == MaxVal + 1)
// Clause 6.4.4 - The value of a constant shall be in the range of
// representable values for its type, with exception for constants of a
// fract type with a value of exactly 1; such a constant shall denote
// the maximal value for the type.
--Val;
else if (Val.ugt(MaxVal) || Overflowed)
Diag(Tok.getLocation(), diag::err_too_large_for_fixed_point);
Res = FixedPointLiteral::CreateFromRawInt(Context, Val, Ty,
Tok.getLocation(), scale);
} else if (Literal.isFloatingLiteral()) {
QualType Ty;
if (Literal.isHalf){
if (getOpenCLOptions().isEnabled("cl_khr_fp16"))
Ty = Context.HalfTy;
else {
Diag(Tok.getLocation(), diag::err_half_const_requires_fp16);
return ExprError();
}
} else if (Literal.isFloat)
Ty = Context.FloatTy;
else if (Literal.isLong)
Ty = Context.LongDoubleTy;
else if (Literal.isFloat16)
Ty = Context.Float16Ty;
else if (Literal.isFloat128)
Ty = Context.Float128Ty;
else
Ty = Context.DoubleTy;
Res = BuildFloatingLiteral(*this, Literal, Ty, Tok.getLocation());
if (Ty == Context.DoubleTy) {
if (getLangOpts().SinglePrecisionConstants) {
const BuiltinType *BTy = Ty->getAs<BuiltinType>();
if (BTy->getKind() != BuiltinType::Float) {
Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).get();
}
} else if (getLangOpts().OpenCL &&
!getOpenCLOptions().isEnabled("cl_khr_fp64")) {
// Impose single-precision float type when cl_khr_fp64 is not enabled.
Diag(Tok.getLocation(), diag::warn_double_const_requires_fp64);
Res = ImpCastExprToType(Res, Context.FloatTy, CK_FloatingCast).get();
}
}
} else if (!Literal.isIntegerLiteral()) {
return ExprError();
} else {
QualType Ty;
// 'long long' is a C99 or C++11 feature.
if (!getLangOpts().C99 && Literal.isLongLong) {
if (getLangOpts().CPlusPlus)
Diag(Tok.getLocation(),
getLangOpts().CPlusPlus11 ?
diag::warn_cxx98_compat_longlong : diag::ext_cxx11_longlong);
else
Diag(Tok.getLocation(), diag::ext_c99_longlong);
}
// Get the value in the widest-possible width.
unsigned MaxWidth = Context.getTargetInfo().getIntMaxTWidth();
llvm::APInt ResultVal(MaxWidth, 0);
if (Literal.GetIntegerValue(ResultVal)) {
// If this value didn't fit into uintmax_t, error and force to ull.
Diag(Tok.getLocation(), diag::err_integer_literal_too_large)
<< /* Unsigned */ 1;
Ty = Context.UnsignedLongLongTy;
assert(Context.getTypeSize(Ty) == ResultVal.getBitWidth() &&
"long long is not intmax_t?");
} else {
// If this value fits into a ULL, try to figure out what else it fits into
// according to the rules of C99 6.4.4.1p5.
// Octal, Hexadecimal, and integers with a U suffix are allowed to
// be an unsigned int.
bool AllowUnsigned = Literal.isUnsigned || Literal.getRadix() != 10;
// Check from smallest to largest, picking the smallest type we can.
unsigned Width = 0;
// Microsoft specific integer suffixes are explicitly sized.
if (Literal.MicrosoftInteger) {
if (Literal.MicrosoftInteger == 8 && !Literal.isUnsigned) {
Width = 8;
Ty = Context.CharTy;
} else {
Width = Literal.MicrosoftInteger;
Ty = Context.getIntTypeForBitwidth(Width,
/*Signed=*/!Literal.isUnsigned);
}
}
if (Ty.isNull() && !Literal.isLong && !Literal.isLongLong) {
// Are int/unsigned possibilities?
unsigned IntSize = Context.getTargetInfo().getIntWidth();
// Does it fit in a unsigned int?
if (ResultVal.isIntN(IntSize)) {
// Does it fit in a signed int?
if (!Literal.isUnsigned && ResultVal[IntSize-1] == 0)
Ty = Context.IntTy;
else if (AllowUnsigned)
Ty = Context.UnsignedIntTy;
Width = IntSize;
}
}
// Are long/unsigned long possibilities?
if (Ty.isNull() && !Literal.isLongLong) {
unsigned LongSize = Context.getTargetInfo().getLongWidth();
// Does it fit in a unsigned long?
if (ResultVal.isIntN(LongSize)) {
// Does it fit in a signed long?
if (!Literal.isUnsigned && ResultVal[LongSize-1] == 0)
Ty = Context.LongTy;
else if (AllowUnsigned)
Ty = Context.UnsignedLongTy;
// Check according to the rules of C90 6.1.3.2p5. C++03 [lex.icon]p2
// is compatible.
else if (!getLangOpts().C99 && !getLangOpts().CPlusPlus11) {
const unsigned LongLongSize =
Context.getTargetInfo().getLongLongWidth();
Diag(Tok.getLocation(),
getLangOpts().CPlusPlus
? Literal.isLong
? diag::warn_old_implicitly_unsigned_long_cxx
: /*C++98 UB*/ diag::
ext_old_implicitly_unsigned_long_cxx
: diag::warn_old_implicitly_unsigned_long)
<< (LongLongSize > LongSize ? /*will have type 'long long'*/ 0
: /*will be ill-formed*/ 1);
Ty = Context.UnsignedLongTy;
}
Width = LongSize;
}
}
// Check long long if needed.
if (Ty.isNull()) {
unsigned LongLongSize = Context.getTargetInfo().getLongLongWidth();
// Does it fit in a unsigned long long?
if (ResultVal.isIntN(LongLongSize)) {
// Does it fit in a signed long long?
// To be compatible with MSVC, hex integer literals ending with the
// LL or i64 suffix are always signed in Microsoft mode.
if (!Literal.isUnsigned && (ResultVal[LongLongSize-1] == 0 ||
(getLangOpts().MSVCCompat && Literal.isLongLong)))
Ty = Context.LongLongTy;
else if (AllowUnsigned)
Ty = Context.UnsignedLongLongTy;
Width = LongLongSize;
}
}
// If we still couldn't decide a type, we probably have something that
// does not fit in a signed long long, but has no U suffix.
if (Ty.isNull()) {
Diag(Tok.getLocation(), diag::ext_integer_literal_too_large_for_signed);
Ty = Context.UnsignedLongLongTy;
Width = Context.getTargetInfo().getLongLongWidth();
}
if (ResultVal.getBitWidth() != Width)
ResultVal = ResultVal.trunc(Width);
}
Res = IntegerLiteral::Create(Context, ResultVal, Ty, Tok.getLocation());
}
// If this is an imaginary literal, create the ImaginaryLiteral wrapper.
if (Literal.isImaginary) {
Res = new (Context) ImaginaryLiteral(Res,
Context.getComplexType(Res->getType()));
Diag(Tok.getLocation(), diag::ext_imaginary_constant);
}
return Res;
}
ExprResult Sema::ActOnParenExpr(SourceLocation L, SourceLocation R, Expr *E) {
assert(E && "ActOnParenExpr() missing expr");
return new (Context) ParenExpr(L, R, E);
}
static bool CheckVecStepTraitOperandType(Sema &S, QualType T,
SourceLocation Loc,
SourceRange ArgRange) {
// [OpenCL 1.1 6.11.12] "The vec_step built-in function takes a built-in
// scalar or vector data type argument..."
// Every built-in scalar type (OpenCL 1.1 6.1.1) is either an arithmetic
// type (C99 6.2.5p18) or void.
if (!(T->isArithmeticType() || T->isVoidType() || T->isVectorType())) {
S.Diag(Loc, diag::err_vecstep_non_scalar_vector_type)
<< T << ArgRange;
return true;
}
assert((T->isVoidType() || !T->isIncompleteType()) &&
"Scalar types should always be complete");
return false;
}
static bool CheckExtensionTraitOperandType(Sema &S, QualType T,
SourceLocation Loc,
SourceRange ArgRange,
UnaryExprOrTypeTrait TraitKind) {
// Invalid types must be hard errors for SFINAE in C++.
if (S.LangOpts.CPlusPlus)
return true;
// C99 6.5.3.4p1:
if (T->isFunctionType() &&
(TraitKind == UETT_SizeOf || TraitKind == UETT_AlignOf)) {
// sizeof(function)/alignof(function) is allowed as an extension.
S.Diag(Loc, diag::ext_sizeof_alignof_function_type)
<< TraitKind << ArgRange;
return false;
}
// Allow sizeof(void)/alignof(void) as an extension, unless in OpenCL where
// this is an error (OpenCL v1.1 s6.3.k)
if (T->isVoidType()) {
unsigned DiagID = S.LangOpts.OpenCL ? diag::err_opencl_sizeof_alignof_type
: diag::ext_sizeof_alignof_void_type;
S.Diag(Loc, DiagID) << TraitKind << ArgRange;
return false;
}
return true;
}
static bool CheckObjCTraitOperandConstraints(Sema &S, QualType T,
SourceLocation Loc,
SourceRange ArgRange,
UnaryExprOrTypeTrait TraitKind) {
// Reject sizeof(interface) and sizeof(interface<proto>) if the
// runtime doesn't allow it.
if (!S.LangOpts.ObjCRuntime.allowsSizeofAlignof() && T->isObjCObjectType()) {
S.Diag(Loc, diag::err_sizeof_nonfragile_interface)
<< T << (TraitKind == UETT_SizeOf)
<< ArgRange;
return true;
}
return false;
}
/// Check whether E is a pointer from a decayed array type (the decayed
/// pointer type is equal to T) and emit a warning if it is.
static void warnOnSizeofOnArrayDecay(Sema &S, SourceLocation Loc, QualType T,
Expr *E) {
// Don't warn if the operation changed the type.
if (T != E->getType())
return;
// Now look for array decays.
ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E);
if (!ICE || ICE->getCastKind() != CK_ArrayToPointerDecay)
return;
S.Diag(Loc, diag::warn_sizeof_array_decay) << ICE->getSourceRange()
<< ICE->getType()
<< ICE->getSubExpr()->getType();
}
/// Check the constraints on expression operands to unary type expression
/// and type traits.
///
/// Completes any types necessary and validates the constraints on the operand
/// expression. The logic mostly mirrors the type-based overload, but may modify
/// the expression as it completes the type for that expression through template
/// instantiation, etc.
bool Sema::CheckUnaryExprOrTypeTraitOperand(Expr *E,
UnaryExprOrTypeTrait ExprKind) {
QualType ExprTy = E->getType();
assert(!ExprTy->isReferenceType());
if (ExprKind == UETT_VecStep)
return CheckVecStepTraitOperandType(*this, ExprTy, E->getExprLoc(),
E->getSourceRange());
// Whitelist some types as extensions
if (!CheckExtensionTraitOperandType(*this, ExprTy, E->getExprLoc(),
E->getSourceRange(), ExprKind))
return false;
// 'alignof' applied to an expression only requires the base element type of
// the expression to be complete. 'sizeof' requires the expression's type to
// be complete (and will attempt to complete it if it's an array of unknown
// bound).
if (ExprKind == UETT_AlignOf) {
if (RequireCompleteType(E->getExprLoc(),
Context.getBaseElementType(E->getType()),
diag::err_sizeof_alignof_incomplete_type, ExprKind,
E->getSourceRange()))
return true;
} else {
if (RequireCompleteExprType(E, diag::err_sizeof_alignof_incomplete_type,
ExprKind, E->getSourceRange()))
return true;
}
// Completing the expression's type may have changed it.
ExprTy = E->getType();
assert(!ExprTy->isReferenceType());
if (ExprTy->isFunctionType()) {
Diag(E->getExprLoc(), diag::err_sizeof_alignof_function_type)
<< ExprKind << E->getSourceRange();
return true;
}
// The operand for sizeof and alignof is in an unevaluated expression context,
// so side effects could result in unintended consequences.
if ((ExprKind == UETT_SizeOf || ExprKind == UETT_AlignOf) &&
!inTemplateInstantiation() && E->HasSideEffects(Context, false))
Diag(E->getExprLoc(), diag::warn_side_effects_unevaluated_context);
if (CheckObjCTraitOperandConstraints(*this, ExprTy, E->getExprLoc(),
E->getSourceRange(), ExprKind))
return true;
if (ExprKind == UETT_SizeOf) {
if (DeclRefExpr *DeclRef = dyn_cast<DeclRefExpr>(E->IgnoreParens())) {
if (ParmVarDecl *PVD = dyn_cast<ParmVarDecl>(DeclRef->getFoundDecl())) {
QualType OType = PVD->getOriginalType();
QualType Type = PVD->getType();
if (Type->isPointerType() && OType->isArrayType()) {
Diag(E->getExprLoc(), diag::warn_sizeof_array_param)
<< Type << OType;
Diag(PVD->getLocation(), diag::note_declared_at);
}
}
}
// Warn on "sizeof(array op x)" and "sizeof(x op array)", where the array
// decays into a pointer and returns an unintended result. This is most
// likely a typo for "sizeof(array) op x".
if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E->IgnoreParens())) {
warnOnSizeofOnArrayDecay(*this, BO->getOperatorLoc(), BO->getType(),
BO->getLHS());
warnOnSizeofOnArrayDecay(*this, BO->getOperatorLoc(), BO->getType(),
BO->getRHS());
}
}
return false;
}
/// Check the constraints on operands to unary expression and type
/// traits.
///
/// This will complete any types necessary, and validate the various constraints
/// on those operands.
///
/// The UsualUnaryConversions() function is *not* called by this routine.
/// C99 6.3.2.1p[2-4] all state:
/// Except when it is the operand of the sizeof operator ...
///
/// C++ [expr.sizeof]p4
/// The lvalue-to-rvalue, array-to-pointer, and function-to-pointer
/// standard conversions are not applied to the operand of sizeof.
///
/// This policy is followed for all of the unary trait expressions.
bool Sema::CheckUnaryExprOrTypeTraitOperand(QualType ExprType,
SourceLocation OpLoc,
SourceRange ExprRange,
UnaryExprOrTypeTrait ExprKind) {
if (ExprType->isDependentType())
return false;
// C++ [expr.sizeof]p2:
// When applied to a reference or a reference type, the result
// is the size of the referenced type.
// C++11 [expr.alignof]p3:
// When alignof is applied to a reference type, the result
// shall be the alignment of the referenced type.
if (const ReferenceType *Ref = ExprType->getAs<ReferenceType>())
ExprType = Ref->getPointeeType();
// C11 6.5.3.4/3, C++11 [expr.alignof]p3:
// When alignof or _Alignof is applied to an array type, the result
// is the alignment of the element type.
if (ExprKind == UETT_AlignOf || ExprKind == UETT_OpenMPRequiredSimdAlign)
ExprType = Context.getBaseElementType(ExprType);
if (ExprKind == UETT_VecStep)
return CheckVecStepTraitOperandType(*this, ExprType, OpLoc, ExprRange);
// Whitelist some types as extensions
if (!CheckExtensionTraitOperandType(*this, ExprType, OpLoc, ExprRange,
ExprKind))
return false;
if (RequireCompleteType(OpLoc, ExprType,
diag::err_sizeof_alignof_incomplete_type,
ExprKind, ExprRange))
return true;
if (ExprType->isFunctionType()) {
Diag(OpLoc, diag::err_sizeof_alignof_function_type)
<< ExprKind << ExprRange;
return true;
}
if (CheckObjCTraitOperandConstraints(*this, ExprType, OpLoc, ExprRange,
ExprKind))
return true;
return false;
}
static bool CheckAlignOfExpr(Sema &S, Expr *E) {
E = E->IgnoreParens();
// Cannot know anything else if the expression is dependent.
if (E->isTypeDependent())
return false;
if (E->getObjectKind() == OK_BitField) {
S.Diag(E->getExprLoc(), diag::err_sizeof_alignof_typeof_bitfield)
<< 1 << E->getSourceRange();
return true;
}
ValueDecl *D = nullptr;
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
D = DRE->getDecl();
} else if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
D = ME->getMemberDecl();
}
// If it's a field, require the containing struct to have a
// complete definition so that we can compute the layout.
//
// This can happen in C++11 onwards, either by naming the member
// in a way that is not transformed into a member access expression
// (in an unevaluated operand, for instance), or by naming the member
// in a trailing-return-type.
//
// For the record, since __alignof__ on expressions is a GCC
// extension, GCC seems to permit this but always gives the
// nonsensical answer 0.
//
// We don't really need the layout here --- we could instead just
// directly check for all the appropriate alignment-lowing
// attributes --- but that would require duplicating a lot of
// logic that just isn't worth duplicating for such a marginal
// use-case.
if (FieldDecl *FD = dyn_cast_or_null<FieldDecl>(D)) {
// Fast path this check, since we at least know the record has a
// definition if we can find a member of it.
if (!FD->getParent()->isCompleteDefinition()) {
S.Diag(E->getExprLoc(), diag::err_alignof_member_of_incomplete_type)
<< E->getSourceRange();
return true;
}
// Otherwise, if it's a field, and the field doesn't have
// reference type, then it must have a complete type (or be a
// flexible array member, which we explicitly want to
// white-list anyway), which makes the following checks trivial.
if (!FD->getType()->isReferenceType())
return false;
}
return S.CheckUnaryExprOrTypeTraitOperand(E, UETT_AlignOf);
}
bool Sema::CheckVecStepExpr(Expr *E) {
E = E->IgnoreParens();
// Cannot know anything else if the expression is dependent.
if (E->isTypeDependent())
return false;
return CheckUnaryExprOrTypeTraitOperand(E, UETT_VecStep);
}
static void captureVariablyModifiedType(ASTContext &Context, QualType T,
CapturingScopeInfo *CSI) {
assert(T->isVariablyModifiedType());
assert(CSI != nullptr);
// We're going to walk down into the type and look for VLA expressions.
do {
const Type *Ty = T.getTypePtr();
switch (Ty->getTypeClass()) {
#define TYPE(Class, Base)
#define ABSTRACT_TYPE(Class, Base)
#define NON_CANONICAL_TYPE(Class, Base)
#define DEPENDENT_TYPE(Class, Base) case Type::Class:
#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base)
#include "clang/AST/TypeNodes.def"
T = QualType();
break;
// These types are never variably-modified.
case Type::Builtin:
case Type::Complex:
case Type::Vector:
case Type::ExtVector:
case Type::Record:
case Type::Enum:
case Type::Elaborated:
case Type::TemplateSpecialization:
case Type::ObjCObject:
case Type::ObjCInterface:
case Type::ObjCObjectPointer:
case Type::ObjCTypeParam:
case Type::Pipe:
llvm_unreachable("type class is never variably-modified!");
case Type::Adjusted:
T = cast<AdjustedType>(Ty)->getOriginalType();
break;
case Type::Decayed:
T = cast<DecayedType>(Ty)->getPointeeType();
break;
case Type::Pointer:
T = cast<PointerType>(Ty)->getPointeeType();
break;
case Type::BlockPointer:
T = cast<BlockPointerType>(Ty)->getPointeeType();
break;
case Type::LValueReference:
case Type::RValueReference:
T = cast<ReferenceType>(Ty)->getPointeeType();
break;
case Type::MemberPointer:
T = cast<MemberPointerType>(Ty)->getPointeeType();
break;
case Type::ConstantArray:
case Type::IncompleteArray:
// Losing element qualification here is fine.
T = cast<ArrayType>(Ty)->getElementType();
break;
case Type::VariableArray: {
// Losing element qualification here is fine.
const VariableArrayType *VAT = cast<VariableArrayType>(Ty);
// Unknown size indication requires no size computation.
// Otherwise, evaluate and record it.
if (auto Size = VAT->getSizeExpr()) {
if (!CSI->isVLATypeCaptured(VAT)) {
RecordDecl *CapRecord = nullptr;
if (auto LSI = dyn_cast<LambdaScopeInfo>(CSI)) {
CapRecord = LSI->Lambda;
} else if (auto CRSI = dyn_cast<CapturedRegionScopeInfo>(CSI)) {
CapRecord = CRSI->TheRecordDecl;
}
if (CapRecord) {
auto ExprLoc = Size->getExprLoc();
auto SizeType = Context.getSizeType();
// Build the non-static data member.
auto Field =
FieldDecl::Create(Context, CapRecord, ExprLoc, ExprLoc,
/*Id*/ nullptr, SizeType, /*TInfo*/ nullptr,
/*BW*/ nullptr, /*Mutable*/ false,
/*InitStyle*/ ICIS_NoInit);
Field->setImplicit(true);
Field->setAccess(AS_private);
Field->setCapturedVLAType(VAT);
CapRecord->addDecl(Field);
CSI->addVLATypeCapture(ExprLoc, SizeType);
}
}
}
T = VAT->getElementType();
break;
}
case Type::FunctionProto:
case Type::FunctionNoProto:
T = cast<FunctionType>(Ty)->getReturnType();
break;
case Type::Paren:
case Type::TypeOf:
case Type::UnaryTransform:
case Type::Attributed:
case Type::SubstTemplateTypeParm:
case Type::PackExpansion:
// Keep walking after single level desugaring.
T = T.getSingleStepDesugaredType(Context);
break;
case Type::Typedef:
T = cast<TypedefType>(Ty)->desugar();
break;
case Type::Decltype:
T = cast<DecltypeType>(Ty)->desugar();
break;
case Type::Auto:
case Type::DeducedTemplateSpecialization:
T = cast<DeducedType>(Ty)->getDeducedType();
break;
case Type::TypeOfExpr:
T = cast<TypeOfExprType>(Ty)->getUnderlyingExpr()->getType();
break;
case Type::Atomic:
T = cast<AtomicType>(Ty)->getValueType();
break;
}
} while (!T.isNull() && T->isVariablyModifiedType());
}
/// Build a sizeof or alignof expression given a type operand.
ExprResult
Sema::CreateUnaryExprOrTypeTraitExpr(TypeSourceInfo *TInfo,
SourceLocation OpLoc,
UnaryExprOrTypeTrait ExprKind,
SourceRange R) {
if (!TInfo)
return ExprError();
QualType T = TInfo->getType();
if (!T->isDependentType() &&
CheckUnaryExprOrTypeTraitOperand(T, OpLoc, R, ExprKind))
return ExprError();
if (T->isVariablyModifiedType() && FunctionScopes.size() > 1) {
if (auto *TT = T->getAs<TypedefType>()) {
for (auto I = FunctionScopes.rbegin(),
E = std::prev(FunctionScopes.rend());
I != E; ++I) {
auto *CSI = dyn_cast<CapturingScopeInfo>(*I);
if (CSI == nullptr)
break;
DeclContext *DC = nullptr;
if (auto *LSI = dyn_cast<LambdaScopeInfo>(CSI))
DC = LSI->CallOperator;
else if (auto *CRSI = dyn_cast<CapturedRegionScopeInfo>(CSI))
DC = CRSI->TheCapturedDecl;
else if (auto *BSI = dyn_cast<BlockScopeInfo>(CSI))
DC = BSI->TheDecl;
if (DC) {
if (DC->containsDecl(TT->getDecl()))
break;
captureVariablyModifiedType(Context, T, CSI);
}
}
}
}
// C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
return new (Context) UnaryExprOrTypeTraitExpr(
ExprKind, TInfo, Context.getSizeType(), OpLoc, R.getEnd());
}
/// Build a sizeof or alignof expression given an expression
/// operand.
ExprResult
Sema::CreateUnaryExprOrTypeTraitExpr(Expr *E, SourceLocation OpLoc,
UnaryExprOrTypeTrait ExprKind) {
ExprResult PE = CheckPlaceholderExpr(E);
if (PE.isInvalid())
return ExprError();
E = PE.get();
// Verify that the operand is valid.
bool isInvalid = false;
if (E->isTypeDependent()) {
// Delay type-checking for type-dependent expressions.
} else if (ExprKind == UETT_AlignOf) {
isInvalid = CheckAlignOfExpr(*this, E);
} else if (ExprKind == UETT_VecStep) {
isInvalid = CheckVecStepExpr(E);
} else if (ExprKind == UETT_OpenMPRequiredSimdAlign) {
Diag(E->getExprLoc(), diag::err_openmp_default_simd_align_expr);
isInvalid = true;
} else if (E->refersToBitField()) { // C99 6.5.3.4p1.
Diag(E->getExprLoc(), diag::err_sizeof_alignof_typeof_bitfield) << 0;
isInvalid = true;
} else {
isInvalid = CheckUnaryExprOrTypeTraitOperand(E, UETT_SizeOf);
}
if (isInvalid)
return ExprError();
if (ExprKind == UETT_SizeOf && E->getType()->isVariableArrayType()) {
PE = TransformToPotentiallyEvaluated(E);
if (PE.isInvalid()) return ExprError();
E = PE.get();
}
// C99 6.5.3.4p4: the type (an unsigned integer type) is size_t.
return new (Context) UnaryExprOrTypeTraitExpr(
ExprKind, E, Context.getSizeType(), OpLoc, E->getSourceRange().getEnd());
}
/// ActOnUnaryExprOrTypeTraitExpr - Handle @c sizeof(type) and @c sizeof @c
/// expr and the same for @c alignof and @c __alignof
/// Note that the ArgRange is invalid if isType is false.
ExprResult
Sema::ActOnUnaryExprOrTypeTraitExpr(SourceLocation OpLoc,
UnaryExprOrTypeTrait ExprKind, bool IsType,
void *TyOrEx, SourceRange ArgRange) {
// If error parsing type, ignore.
if (!TyOrEx) return ExprError();
if (IsType) {
TypeSourceInfo *TInfo;
(void) GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrEx), &TInfo);
return CreateUnaryExprOrTypeTraitExpr(TInfo, OpLoc, ExprKind, ArgRange);
}
Expr *ArgEx = (Expr *)TyOrEx;
ExprResult Result = CreateUnaryExprOrTypeTraitExpr(ArgEx, OpLoc, ExprKind);
return Result;
}
static QualType CheckRealImagOperand(Sema &S, ExprResult &V, SourceLocation Loc,
bool IsReal) {
if (V.get()->isTypeDependent())
return S.Context.DependentTy;
// _Real and _Imag are only l-values for normal l-values.
if (V.get()->getObjectKind() != OK_Ordinary) {
V = S.DefaultLvalueConversion(V.get());
if (V.isInvalid())
return QualType();
}
// These operators return the element type of a complex type.
if (const ComplexType *CT = V.get()->getType()->getAs<ComplexType>())
return CT->getElementType();
// Otherwise they pass through real integer and floating point types here.
if (V.get()->getType()->isArithmeticType())
return V.get()->getType();
// Test for placeholders.
ExprResult PR = S.CheckPlaceholderExpr(V.get());
if (PR.isInvalid()) return QualType();
if (PR.get() != V.get()) {
V = PR;
return CheckRealImagOperand(S, V, Loc, IsReal);
}
// Reject anything else.
S.Diag(Loc, diag::err_realimag_invalid_type) << V.get()->getType()
<< (IsReal ? "__real" : "__imag");
return QualType();
}
ExprResult
Sema::ActOnPostfixUnaryOp(Scope *S, SourceLocation OpLoc,
tok::TokenKind Kind, Expr *Input) {
UnaryOperatorKind Opc;
switch (Kind) {
default: llvm_unreachable("Unknown unary op!");
case tok::plusplus: Opc = UO_PostInc; break;
case tok::minusminus: Opc = UO_PostDec; break;
}
// Since this might is a postfix expression, get rid of ParenListExprs.
ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Input);
if (Result.isInvalid()) return ExprError();
Input = Result.get();
return BuildUnaryOp(S, OpLoc, Opc, Input);
}
/// Diagnose if arithmetic on the given ObjC pointer is illegal.
///
/// \return true on error
static bool checkArithmeticOnObjCPointer(Sema &S,
SourceLocation opLoc,
Expr *op) {
assert(op->getType()->isObjCObjectPointerType());
if (S.LangOpts.ObjCRuntime.allowsPointerArithmetic() &&
!S.LangOpts.ObjCSubscriptingLegacyRuntime)
return false;
S.Diag(opLoc, diag::err_arithmetic_nonfragile_interface)
<< op->getType()->castAs<ObjCObjectPointerType>()->getPointeeType()
<< op->getSourceRange();
return true;
}
static bool isMSPropertySubscriptExpr(Sema &S, Expr *Base) {
auto *BaseNoParens = Base->IgnoreParens();
if (auto *MSProp = dyn_cast<MSPropertyRefExpr>(BaseNoParens))
return MSProp->getPropertyDecl()->getType()->isArrayType();
return isa<MSPropertySubscriptExpr>(BaseNoParens);
}
ExprResult
Sema::ActOnArraySubscriptExpr(Scope *S, Expr *base, SourceLocation lbLoc,
Expr *idx, SourceLocation rbLoc) {
if (base && !base->getType().isNull() &&
base->getType()->isSpecificPlaceholderType(BuiltinType::OMPArraySection))
return ActOnOMPArraySectionExpr(base, lbLoc, idx, SourceLocation(),
/*Length=*/nullptr, rbLoc);
// Since this might be a postfix expression, get rid of ParenListExprs.
if (isa<ParenListExpr>(base)) {
ExprResult result = MaybeConvertParenListExprToParenExpr(S, base);
if (result.isInvalid()) return ExprError();
base = result.get();
}
// Handle any non-overload placeholder types in the base and index
// expressions. We can't handle overloads here because the other
// operand might be an overloadable type, in which case the overload
// resolution for the operator overload should get the first crack
// at the overload.
bool IsMSPropertySubscript = false;
if (base->getType()->isNonOverloadPlaceholderType()) {
IsMSPropertySubscript = isMSPropertySubscriptExpr(*this, base);
if (!IsMSPropertySubscript) {
ExprResult result = CheckPlaceholderExpr(base);
if (result.isInvalid())
return ExprError();
base = result.get();
}
}
if (idx->getType()->isNonOverloadPlaceholderType()) {
ExprResult result = CheckPlaceholderExpr(idx);
if (result.isInvalid()) return ExprError();
idx = result.get();
}
// Build an unanalyzed expression if either operand is type-dependent.
if (getLangOpts().CPlusPlus &&
(base->isTypeDependent() || idx->isTypeDependent())) {
return new (Context) ArraySubscriptExpr(base, idx, Context.DependentTy,
VK_LValue, OK_Ordinary, rbLoc);
}
// MSDN, property (C++)
// https://msdn.microsoft.com/en-us/library/yhfk0thd(v=vs.120).aspx
// This attribute can also be used in the declaration of an empty array in a
// class or structure definition. For example:
// __declspec(property(get=GetX, put=PutX)) int x[];
// The above statement indicates that x[] can be used with one or more array
// indices. In this case, i=p->x[a][b] will be turned into i=p->GetX(a, b),
// and p->x[a][b] = i will be turned into p->PutX(a, b, i);
if (IsMSPropertySubscript) {
// Build MS property subscript expression if base is MS property reference
// or MS property subscript.
return new (Context) MSPropertySubscriptExpr(
base, idx, Context.PseudoObjectTy, VK_LValue, OK_Ordinary, rbLoc);
}
// Use C++ overloaded-operator rules if either operand has record
// type. The spec says to do this if either type is *overloadable*,
// but enum types can't declare subscript operators or conversion
// operators, so there's nothing interesting for overload resolution
// to do if there aren't any record types involved.
//
// ObjC pointers have their own subscripting logic that is not tied
// to overload resolution and so should not take this path.
if (getLangOpts().CPlusPlus &&
(base->getType()->isRecordType() ||
(!base->getType()->isObjCObjectPointerType() &&
idx->getType()->isRecordType()))) {
return CreateOverloadedArraySubscriptExpr(lbLoc, rbLoc, base, idx);
}
return CreateBuiltinArraySubscriptExpr(base, lbLoc, idx, rbLoc);
}
ExprResult Sema::ActOnOMPArraySectionExpr(Expr *Base, SourceLocation LBLoc,
Expr *LowerBound,
SourceLocation ColonLoc, Expr *Length,
SourceLocation RBLoc) {
if (Base->getType()->isPlaceholderType() &&
!Base->getType()->isSpecificPlaceholderType(
BuiltinType::OMPArraySection)) {
ExprResult Result = CheckPlaceholderExpr(Base);
if (Result.isInvalid())
return ExprError();
Base = Result.get();
}
if (LowerBound && LowerBound->getType()->isNonOverloadPlaceholderType()) {
ExprResult Result = CheckPlaceholderExpr(LowerBound);
if (Result.isInvalid())
return ExprError();
Result = DefaultLvalueConversion(Result.get());
if (Result.isInvalid())
return ExprError();
LowerBound = Result.get();
}
if (Length && Length->getType()->isNonOverloadPlaceholderType()) {
ExprResult Result = CheckPlaceholderExpr(Length);
if (Result.isInvalid())
return ExprError();
Result = DefaultLvalueConversion(Result.get());
if (Result.isInvalid())
return ExprError();
Length = Result.get();
}
// Build an unanalyzed expression if either operand is type-dependent.
if (Base->isTypeDependent() ||
(LowerBound &&
(LowerBound->isTypeDependent() || LowerBound->isValueDependent())) ||
(Length && (Length->isTypeDependent() || Length->isValueDependent()))) {
return new (Context)
OMPArraySectionExpr(Base, LowerBound, Length, Context.DependentTy,
VK_LValue, OK_Ordinary, ColonLoc, RBLoc);
}
// Perform default conversions.
QualType OriginalTy = OMPArraySectionExpr::getBaseOriginalType(Base);
QualType ResultTy;
if (OriginalTy->isAnyPointerType()) {
ResultTy = OriginalTy->getPointeeType();
} else if (OriginalTy->isArrayType()) {
ResultTy = OriginalTy->getAsArrayTypeUnsafe()->getElementType();
} else {
return ExprError(
Diag(Base->getExprLoc(), diag::err_omp_typecheck_section_value)
<< Base->getSourceRange());
}
// C99 6.5.2.1p1
if (LowerBound) {
auto Res = PerformOpenMPImplicitIntegerConversion(LowerBound->getExprLoc(),
LowerBound);
if (Res.isInvalid())
return ExprError(Diag(LowerBound->getExprLoc(),
diag::err_omp_typecheck_section_not_integer)
<< 0 << LowerBound->getSourceRange());
LowerBound = Res.get();
if (LowerBound->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
LowerBound->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
Diag(LowerBound->getExprLoc(), diag::warn_omp_section_is_char)
<< 0 << LowerBound->getSourceRange();
}
if (Length) {
auto Res =
PerformOpenMPImplicitIntegerConversion(Length->getExprLoc(), Length);
if (Res.isInvalid())
return ExprError(Diag(Length->getExprLoc(),
diag::err_omp_typecheck_section_not_integer)
<< 1 << Length->getSourceRange());
Length = Res.get();
if (Length->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
Length->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
Diag(Length->getExprLoc(), diag::warn_omp_section_is_char)
<< 1 << Length->getSourceRange();
}
// C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly,
// C++ [expr.sub]p1: The type "T" shall be a completely-defined object
// type. Note that functions are not objects, and that (in C99 parlance)
// incomplete types are not object types.
if (ResultTy->isFunctionType()) {
Diag(Base->getExprLoc(), diag::err_omp_section_function_type)
<< ResultTy << Base->getSourceRange();
return ExprError();
}
if (RequireCompleteType(Base->getExprLoc(), ResultTy,
diag::err_omp_section_incomplete_type, Base))
return ExprError();
if (LowerBound && !OriginalTy->isAnyPointerType()) {
llvm::APSInt LowerBoundValue;
if (LowerBound->EvaluateAsInt(LowerBoundValue, Context)) {
// OpenMP 4.5, [2.4 Array Sections]
// The array section must be a subset of the original array.
if (LowerBoundValue.isNegative()) {
Diag(LowerBound->getExprLoc(), diag::err_omp_section_not_subset_of_array)
<< LowerBound->getSourceRange();
return ExprError();
}
}
}
if (Length) {
llvm::APSInt LengthValue;
if (Length->EvaluateAsInt(LengthValue, Context)) {
// OpenMP 4.5, [2.4 Array Sections]
// The length must evaluate to non-negative integers.
if (LengthValue.isNegative()) {
Diag(Length->getExprLoc(), diag::err_omp_section_length_negative)
<< LengthValue.toString(/*Radix=*/10, /*Signed=*/true)
<< Length->getSourceRange();
return ExprError();
}
}
} else if (ColonLoc.isValid() &&
(OriginalTy.isNull() || (!OriginalTy->isConstantArrayType() &&
!OriginalTy->isVariableArrayType()))) {
// OpenMP 4.5, [2.4 Array Sections]
// When the size of the array dimension is not known, the length must be
// specified explicitly.
Diag(ColonLoc, diag::err_omp_section_length_undefined)
<< (!OriginalTy.isNull() && OriginalTy->isArrayType());
return ExprError();
}
if (!Base->getType()->isSpecificPlaceholderType(
BuiltinType::OMPArraySection)) {
ExprResult Result = DefaultFunctionArrayLvalueConversion(Base);
if (Result.isInvalid())
return ExprError();
Base = Result.get();
}
return new (Context)
OMPArraySectionExpr(Base, LowerBound, Length, Context.OMPArraySectionTy,
VK_LValue, OK_Ordinary, ColonLoc, RBLoc);
}
ExprResult
Sema::CreateBuiltinArraySubscriptExpr(Expr *Base, SourceLocation LLoc,
Expr *Idx, SourceLocation RLoc) {
Expr *LHSExp = Base;
Expr *RHSExp = Idx;
ExprValueKind VK = VK_LValue;
ExprObjectKind OK = OK_Ordinary;
// Per C++ core issue 1213, the result is an xvalue if either operand is
// a non-lvalue array, and an lvalue otherwise.
if (getLangOpts().CPlusPlus11) {
for (auto *Op : {LHSExp, RHSExp}) {
Op = Op->IgnoreImplicit();
if (Op->getType()->isArrayType() && !Op->isLValue())
VK = VK_XValue;
}
}
// Perform default conversions.
if (!LHSExp->getType()->getAs<VectorType>()) {
ExprResult Result = DefaultFunctionArrayLvalueConversion(LHSExp);
if (Result.isInvalid())
return ExprError();
LHSExp = Result.get();
}
ExprResult Result = DefaultFunctionArrayLvalueConversion(RHSExp);
if (Result.isInvalid())
return ExprError();
RHSExp = Result.get();
QualType LHSTy = LHSExp->getType(), RHSTy = RHSExp->getType();
// C99 6.5.2.1p2: the expression e1[e2] is by definition precisely equivalent
// to the expression *((e1)+(e2)). This means the array "Base" may actually be
// in the subscript position. As a result, we need to derive the array base
// and index from the expression types.
Expr *BaseExpr, *IndexExpr;
QualType ResultType;
if (LHSTy->isDependentType() || RHSTy->isDependentType()) {
BaseExpr = LHSExp;
IndexExpr = RHSExp;
ResultType = Context.DependentTy;
} else if (const PointerType *PTy = LHSTy->getAs<PointerType>()) {
BaseExpr = LHSExp;
IndexExpr = RHSExp;
ResultType = PTy->getPointeeType();
} else if (const ObjCObjectPointerType *PTy =
LHSTy->getAs<ObjCObjectPointerType>()) {
BaseExpr = LHSExp;
IndexExpr = RHSExp;
// Use custom logic if this should be the pseudo-object subscript
// expression.
if (!LangOpts.isSubscriptPointerArithmetic())
return BuildObjCSubscriptExpression(RLoc, BaseExpr, IndexExpr, nullptr,
nullptr);
ResultType = PTy->getPointeeType();
} else if (const PointerType *PTy = RHSTy->getAs<PointerType>()) {
// Handle the uncommon case of "123[Ptr]".
BaseExpr = RHSExp;
IndexExpr = LHSExp;
ResultType = PTy->getPointeeType();
} else if (const ObjCObjectPointerType *PTy =
RHSTy->getAs<ObjCObjectPointerType>()) {
// Handle the uncommon case of "123[Ptr]".
BaseExpr = RHSExp;
IndexExpr = LHSExp;
ResultType = PTy->getPointeeType();
if (!LangOpts.isSubscriptPointerArithmetic()) {
Diag(LLoc, diag::err_subscript_nonfragile_interface)
<< ResultType << BaseExpr->getSourceRange();
return ExprError();
}
} else if (const VectorType *VTy = LHSTy->getAs<VectorType>()) {
BaseExpr = LHSExp; // vectors: V[123]
IndexExpr = RHSExp;
// We apply C++ DR1213 to vector subscripting too.
if (getLangOpts().CPlusPlus11 && LHSExp->getValueKind() == VK_RValue) {
ExprResult Materialized = TemporaryMaterializationConversion(LHSExp);
if (Materialized.isInvalid())
return ExprError();
LHSExp = Materialized.get();
}
VK = LHSExp->getValueKind();
if (VK != VK_RValue)
OK = OK_VectorComponent;
ResultType = VTy->getElementType();
QualType BaseType = BaseExpr->getType();
Qualifiers BaseQuals = BaseType.getQualifiers();
Qualifiers MemberQuals = ResultType.getQualifiers();
Qualifiers Combined = BaseQuals + MemberQuals;
if (Combined != MemberQuals)
ResultType = Context.getQualifiedType(ResultType, Combined);
} else if (LHSTy->isArrayType()) {
// If we see an array that wasn't promoted by
// DefaultFunctionArrayLvalueConversion, it must be an array that
// wasn't promoted because of the C90 rule that doesn't
// allow promoting non-lvalue arrays. Warn, then
// force the promotion here.
Diag(LHSExp->getLocStart(), diag::ext_subscript_non_lvalue) <<
LHSExp->getSourceRange();
LHSExp = ImpCastExprToType(LHSExp, Context.getArrayDecayedType(LHSTy),
CK_ArrayToPointerDecay).get();
LHSTy = LHSExp->getType();
BaseExpr = LHSExp;
IndexExpr = RHSExp;
ResultType = LHSTy->getAs<PointerType>()->getPointeeType();
} else if (RHSTy->isArrayType()) {
// Same as previous, except for 123[f().a] case
Diag(RHSExp->getLocStart(), diag::ext_subscript_non_lvalue) <<
RHSExp->getSourceRange();
RHSExp = ImpCastExprToType(RHSExp, Context.getArrayDecayedType(RHSTy),
CK_ArrayToPointerDecay).get();
RHSTy = RHSExp->getType();
BaseExpr = RHSExp;
IndexExpr = LHSExp;
ResultType = RHSTy->getAs<PointerType>()->getPointeeType();
} else {
return ExprError(Diag(LLoc, diag::err_typecheck_subscript_value)
<< LHSExp->getSourceRange() << RHSExp->getSourceRange());
}
// C99 6.5.2.1p1
if (!IndexExpr->getType()->isIntegerType() && !IndexExpr->isTypeDependent())
return ExprError(Diag(LLoc, diag::err_typecheck_subscript_not_integer)
<< IndexExpr->getSourceRange());
if ((IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_S) ||
IndexExpr->getType()->isSpecificBuiltinType(BuiltinType::Char_U))
&& !IndexExpr->isTypeDependent())
Diag(LLoc, diag::warn_subscript_is_char) << IndexExpr->getSourceRange();
// C99 6.5.2.1p1: "shall have type "pointer to *object* type". Similarly,
// C++ [expr.sub]p1: The type "T" shall be a completely-defined object
// type. Note that Functions are not objects, and that (in C99 parlance)
// incomplete types are not object types.
if (ResultType->isFunctionType()) {
Diag(BaseExpr->getLocStart(), diag::err_subscript_function_type)
<< ResultType << BaseExpr->getSourceRange();
return ExprError();
}
if (ResultType->isVoidType() && !getLangOpts().CPlusPlus) {
// GNU extension: subscripting on pointer to void
Diag(LLoc, diag::ext_gnu_subscript_void_type)
<< BaseExpr->getSourceRange();
// C forbids expressions of unqualified void type from being l-values.
// See IsCForbiddenLValueType.
if (!ResultType.hasQualifiers()) VK = VK_RValue;
} else if (!ResultType->isDependentType() &&
RequireCompleteType(LLoc, ResultType,
diag::err_subscript_incomplete_type, BaseExpr))
return ExprError();
assert(VK == VK_RValue || LangOpts.CPlusPlus ||
!ResultType.isCForbiddenLValueType());
return new (Context)
ArraySubscriptExpr(LHSExp, RHSExp, ResultType, VK, OK, RLoc);
}
bool Sema::CheckCXXDefaultArgExpr(SourceLocation CallLoc, FunctionDecl *FD,
ParmVarDecl *Param) {
if (Param->hasUnparsedDefaultArg()) {
Diag(CallLoc,
diag::err_use_of_default_argument_to_function_declared_later) <<
FD << cast<CXXRecordDecl>(FD->getDeclContext())->getDeclName();
Diag(UnparsedDefaultArgLocs[Param],
diag::note_default_argument_declared_here);
return true;
}
if (Param->hasUninstantiatedDefaultArg()) {
Expr *UninstExpr = Param->getUninstantiatedDefaultArg();
EnterExpressionEvaluationContext EvalContext(
*this, ExpressionEvaluationContext::PotentiallyEvaluated, Param);
// Instantiate the expression.
//
// FIXME: Pass in a correct Pattern argument, otherwise
// getTemplateInstantiationArgs uses the lexical context of FD, e.g.
//
// template<typename T>
// struct A {
// static int FooImpl();
//
// template<typename Tp>
// // bug: default argument A<T>::FooImpl() is evaluated with 2-level
// // template argument list [[T], [Tp]], should be [[Tp]].
// friend A<Tp> Foo(int a);
// };
//
// template<typename T>
// A<T> Foo(int a = A<T>::FooImpl());
MultiLevelTemplateArgumentList MutiLevelArgList
= getTemplateInstantiationArgs(FD, nullptr, /*RelativeToPrimary=*/true);
InstantiatingTemplate Inst(*this, CallLoc, Param,
MutiLevelArgList.getInnermost());
if (Inst.isInvalid())
return true;
if (Inst.isAlreadyInstantiating()) {
Diag(Param->getLocStart(), diag::err_recursive_default_argument) << FD;
Param->setInvalidDecl();
return true;
}
ExprResult Result;
{
// C++ [dcl.fct.default]p5:
// The names in the [default argument] expression are bound, and
// the semantic constraints are checked, at the point where the
// default argument expression appears.
ContextRAII SavedContext(*this, FD);
LocalInstantiationScope Local(*this);
Result = SubstInitializer(UninstExpr, MutiLevelArgList,
/*DirectInit*/false);
}
if (Result.isInvalid())
return true;
// Check the expression as an initializer for the parameter.
InitializedEntity Entity
= InitializedEntity::InitializeParameter(Context, Param);
InitializationKind Kind
= InitializationKind::CreateCopy(Param->getLocation(),
/*FIXME:EqualLoc*/UninstExpr->getLocStart());
Expr *ResultE = Result.getAs<Expr>();
InitializationSequence InitSeq(*this, Entity, Kind, ResultE);
Result = InitSeq.Perform(*this, Entity, Kind, ResultE);
if (Result.isInvalid())
return true;
Result = ActOnFinishFullExpr(Result.getAs<Expr>(),
Param->getOuterLocStart());
if (Result.isInvalid())
return true;
// Remember the instantiated default argument.
Param->setDefaultArg(Result.getAs<Expr>());
if (ASTMutationListener *L = getASTMutationListener()) {
L->DefaultArgumentInstantiated(Param);
}
}
// If the default argument expression is not set yet, we are building it now.
if (!Param->hasInit()) {
Diag(Param->getLocStart(), diag::err_recursive_default_argument) << FD;
Param->setInvalidDecl();
return true;
}
// If the default expression creates temporaries, we need to
// push them to the current stack of expression temporaries so they'll
// be properly destroyed.
// FIXME: We should really be rebuilding the default argument with new
// bound temporaries; see the comment in PR5810.
// We don't need to do that with block decls, though, because
// blocks in default argument expression can never capture anything.
if (auto Init = dyn_cast<ExprWithCleanups>(Param->getInit())) {
// Set the "needs cleanups" bit regardless of whether there are
// any explicit objects.
Cleanup.setExprNeedsCleanups(Init->cleanupsHaveSideEffects());
// Append all the objects to the cleanup list. Right now, this
// should always be a no-op, because blocks in default argument
// expressions should never be able to capture anything.
assert(!Init->getNumObjects() &&
"default argument expression has capturing blocks?");
}
// We already type-checked the argument, so we know it works.
// Just mark all of the declarations in this potentially-evaluated expression
// as being "referenced".
MarkDeclarationsReferencedInExpr(Param->getDefaultArg(),
/*SkipLocalVariables=*/true);
return false;
}
ExprResult Sema::BuildCXXDefaultArgExpr(SourceLocation CallLoc,
FunctionDecl *FD, ParmVarDecl *Param) {
if (CheckCXXDefaultArgExpr(CallLoc, FD, Param))
return ExprError();
return CXXDefaultArgExpr::Create(Context, CallLoc, Param);
}
Sema::VariadicCallType
Sema::getVariadicCallType(FunctionDecl *FDecl, const FunctionProtoType *Proto,
Expr *Fn) {
if (Proto && Proto->isVariadic()) {
if (dyn_cast_or_null<CXXConstructorDecl>(FDecl))
return VariadicConstructor;
else if (Fn && Fn->getType()->isBlockPointerType())
return VariadicBlock;
else if (FDecl) {
if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl))
if (Method->isInstance())
return VariadicMethod;
} else if (Fn && Fn->getType() == Context.BoundMemberTy)
return VariadicMethod;
return VariadicFunction;
}
return VariadicDoesNotApply;
}
namespace {
class FunctionCallCCC : public FunctionCallFilterCCC {
public:
FunctionCallCCC(Sema &SemaRef, const IdentifierInfo *FuncName,
unsigned NumArgs, MemberExpr *ME)
: FunctionCallFilterCCC(SemaRef, NumArgs, false, ME),
FunctionName(FuncName) {}
bool ValidateCandidate(const TypoCorrection &candidate) override {
if (!candidate.getCorrectionSpecifier() ||
candidate.getCorrectionAsIdentifierInfo() != FunctionName) {
return false;
}
return FunctionCallFilterCCC::ValidateCandidate(candidate);
}
private:
const IdentifierInfo *const FunctionName;
};
}
static TypoCorrection TryTypoCorrectionForCall(Sema &S, Expr *Fn,
FunctionDecl *FDecl,
ArrayRef<Expr *> Args) {
MemberExpr *ME = dyn_cast<MemberExpr>(Fn);
DeclarationName FuncName = FDecl->getDeclName();
SourceLocation NameLoc = ME ? ME->getMemberLoc() : Fn->getLocStart();
if (TypoCorrection Corrected = S.CorrectTypo(
DeclarationNameInfo(FuncName, NameLoc), Sema::LookupOrdinaryName,
S.getScopeForContext(S.CurContext), nullptr,
llvm::make_unique<FunctionCallCCC>(S, FuncName.getAsIdentifierInfo(),
Args.size(), ME),
Sema::CTK_ErrorRecovery)) {
if (NamedDecl *ND = Corrected.getFoundDecl()) {
if (Corrected.isOverloaded()) {
OverloadCandidateSet OCS(NameLoc, OverloadCandidateSet::CSK_Normal);
OverloadCandidateSet::iterator Best;
for (NamedDecl *CD : Corrected) {
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(CD))
S.AddOverloadCandidate(FD, DeclAccessPair::make(FD, AS_none), Args,
OCS);
}
switch (OCS.BestViableFunction(S, NameLoc, Best)) {
case OR_Success:
ND = Best->FoundDecl;
Corrected.setCorrectionDecl(ND);
break;
default:
break;
}
}
ND = ND->getUnderlyingDecl();
if (isa<ValueDecl>(ND) || isa<FunctionTemplateDecl>(ND))
return Corrected;
}
}
return TypoCorrection();
}
/// ConvertArgumentsForCall - Converts the arguments specified in
/// Args/NumArgs to the parameter types of the function FDecl with
/// function prototype Proto. Call is the call expression itself, and
/// Fn is the function expression. For a C++ member function, this
/// routine does not attempt to convert the object argument. Returns
/// true if the call is ill-formed.
bool
Sema::ConvertArgumentsForCall(CallExpr *Call, Expr *Fn,
FunctionDecl *FDecl,
const FunctionProtoType *Proto,
ArrayRef<Expr *> Args,
SourceLocation RParenLoc,
bool IsExecConfig) {
// Bail out early if calling a builtin with custom typechecking.
if (FDecl)
if (unsigned ID = FDecl->getBuiltinID())
if (Context.BuiltinInfo.hasCustomTypechecking(ID))
return false;
// C99 6.5.2.2p7 - the arguments are implicitly converted, as if by
// assignment, to the types of the corresponding parameter, ...
unsigned NumParams = Proto->getNumParams();
bool Invalid = false;
unsigned MinArgs = FDecl ? FDecl->getMinRequiredArguments() : NumParams;
unsigned FnKind = Fn->getType()->isBlockPointerType()
? 1 /* block */
: (IsExecConfig ? 3 /* kernel function (exec config) */
: 0 /* function */);
// If too few arguments are available (and we don't have default
// arguments for the remaining parameters), don't make the call.
if (Args.size() < NumParams) {
if (Args.size() < MinArgs) {
TypoCorrection TC;
if (FDecl && (TC = TryTypoCorrectionForCall(*this, Fn, FDecl, Args))) {
unsigned diag_id =
MinArgs == NumParams && !Proto->isVariadic()
? diag::err_typecheck_call_too_few_args_suggest
: diag::err_typecheck_call_too_few_args_at_least_suggest;
diagnoseTypo(TC, PDiag(diag_id) << FnKind << MinArgs
<< static_cast<unsigned>(Args.size())
<< TC.getCorrectionRange());
} else if (MinArgs == 1 && FDecl && FDecl->getParamDecl(0)->getDeclName())
Diag(RParenLoc,
MinArgs == NumParams && !Proto->isVariadic()
? diag::err_typecheck_call_too_few_args_one
: diag::err_typecheck_call_too_few_args_at_least_one)
<< FnKind << FDecl->getParamDecl(0) << Fn->getSourceRange();
else
Diag(RParenLoc, MinArgs == NumParams && !Proto->isVariadic()
? diag::err_typecheck_call_too_few_args
: diag::err_typecheck_call_too_few_args_at_least)
<< FnKind << MinArgs << static_cast<unsigned>(Args.size())
<< Fn->getSourceRange();
// Emit the location of the prototype.
if (!TC && FDecl && !FDecl->getBuiltinID() && !IsExecConfig)
Diag(FDecl->getLocStart(), diag::note_callee_decl)
<< FDecl;
return true;
}
Call->setNumArgs(Context, NumParams);
}
// If too many are passed and not variadic, error on the extras and drop
// them.
if (Args.size() > NumParams) {
if (!Proto->isVariadic()) {
TypoCorrection TC;
if (FDecl && (TC = TryTypoCorrectionForCall(*this, Fn, FDecl, Args))) {
unsigned diag_id =
MinArgs == NumParams && !Proto->isVariadic()
? diag::err_typecheck_call_too_many_args_suggest
: diag::err_typecheck_call_too_many_args_at_most_suggest;
diagnoseTypo(TC, PDiag(diag_id) << FnKind << NumParams
<< static_cast<unsigned>(Args.size())
<< TC.getCorrectionRange());
} else if (NumParams == 1 && FDecl &&
FDecl->getParamDecl(0)->getDeclName())
Diag(Args[NumParams]->getLocStart(),
MinArgs == NumParams
? diag::err_typecheck_call_too_many_args_one
: diag::err_typecheck_call_too_many_args_at_most_one)
<< FnKind << FDecl->getParamDecl(0)
<< static_cast<unsigned>(Args.size()) << Fn->getSourceRange()
<< SourceRange(Args[NumParams]->getLocStart(),
Args.back()->getLocEnd());
else
Diag(Args[NumParams]->getLocStart(),
MinArgs == NumParams
? diag::err_typecheck_call_too_many_args
: diag::err_typecheck_call_too_many_args_at_most)
<< FnKind << NumParams << static_cast<unsigned>(Args.size())
<< Fn->getSourceRange()
<< SourceRange(Args[NumParams]->getLocStart(),
Args.back()->getLocEnd());
// Emit the location of the prototype.
if (!TC && FDecl && !FDecl->getBuiltinID() && !IsExecConfig)
Diag(FDecl->getLocStart(), diag::note_callee_decl)
<< FDecl;
// This deletes the extra arguments.
Call->setNumArgs(Context, NumParams);
return true;
}
}
SmallVector<Expr *, 8> AllArgs;
VariadicCallType CallType = getVariadicCallType(FDecl, Proto, Fn);
Invalid = GatherArgumentsForCall(Call->getLocStart(), FDecl,
Proto, 0, Args, AllArgs, CallType);
if (Invalid)
return true;
unsigned TotalNumArgs = AllArgs.size();
for (unsigned i = 0; i < TotalNumArgs; ++i)
Call->setArg(i, AllArgs[i]);
return false;
}
bool Sema::GatherArgumentsForCall(SourceLocation CallLoc, FunctionDecl *FDecl,
const FunctionProtoType *Proto,
unsigned FirstParam, ArrayRef<Expr *> Args,
SmallVectorImpl<Expr *> &AllArgs,
VariadicCallType CallType, bool AllowExplicit,
bool IsListInitialization) {
unsigned NumParams = Proto->getNumParams();
bool Invalid = false;
size_t ArgIx = 0;
// Continue to check argument types (even if we have too few/many args).
for (unsigned i = FirstParam; i < NumParams; i++) {
QualType ProtoArgType = Proto->getParamType(i);
Expr *Arg;
ParmVarDecl *Param = FDecl ? FDecl->getParamDecl(i) : nullptr;
if (ArgIx < Args.size()) {
Arg = Args[ArgIx++];
if (RequireCompleteType(Arg->getLocStart(),
ProtoArgType,
diag::err_call_incomplete_argument, Arg))
return true;
// Strip the unbridged-cast placeholder expression off, if applicable.
bool CFAudited = false;
if (Arg->getType() == Context.ARCUnbridgedCastTy &&
FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() &&
(!Param || !Param->hasAttr<CFConsumedAttr>()))
Arg = stripARCUnbridgedCast(Arg);
else if (getLangOpts().ObjCAutoRefCount &&
FDecl && FDecl->hasAttr<CFAuditedTransferAttr>() &&
(!Param || !Param->hasAttr<CFConsumedAttr>()))
CFAudited = true;
if (Proto->getExtParameterInfo(i).isNoEscape())
if (auto *BE = dyn_cast<BlockExpr>(Arg->IgnoreParenNoopCasts(Context)))
BE->getBlockDecl()->setDoesNotEscape();
InitializedEntity Entity =
Param ? InitializedEntity::InitializeParameter(Context, Param,
ProtoArgType)
: InitializedEntity::InitializeParameter(
Context, ProtoArgType, Proto->isParamConsumed(i));
// Remember that parameter belongs to a CF audited API.
if (CFAudited)
Entity.setParameterCFAudited();
ExprResult ArgE = PerformCopyInitialization(
Entity, SourceLocation(), Arg, IsListInitialization, AllowExplicit);
if (ArgE.isInvalid())
return true;
Arg = ArgE.getAs<Expr>();
} else {
assert(Param && "can't use default arguments without a known callee");
ExprResult ArgExpr =
BuildCXXDefaultArgExpr(CallLoc, FDecl, Param);
if (ArgExpr.isInvalid())
return true;
Arg = ArgExpr.getAs<Expr>();
}
// Check for array bounds violations for each argument to the call. This
// check only triggers warnings when the argument isn't a more complex Expr
// with its own checking, such as a BinaryOperator.
CheckArrayAccess(Arg);
// Check for violations of C99 static array rules (C99 6.7.5.3p7).
CheckStaticArrayArgument(CallLoc, Param, Arg);
AllArgs.push_back(Arg);
}
// If this is a variadic call, handle args passed through "...".
if (CallType != VariadicDoesNotApply) {
// Assume that extern "C" functions with variadic arguments that
// return __unknown_anytype aren't *really* variadic.
if (Proto->getReturnType() == Context.UnknownAnyTy && FDecl &&
FDecl->isExternC()) {
for (Expr *A : Args.slice(ArgIx)) {
QualType paramType; // ignored
ExprResult arg = checkUnknownAnyArg(CallLoc, A, paramType);
Invalid |= arg.isInvalid();
AllArgs.push_back(arg.get());
}
// Otherwise do argument promotion, (C99 6.5.2.2p7).
} else {
for (Expr *A : Args.slice(ArgIx)) {
ExprResult Arg = DefaultVariadicArgumentPromotion(A, CallType, FDecl);
Invalid |= Arg.isInvalid();
AllArgs.push_back(Arg.get());
}
}
// Check for array bounds violations.
for (Expr *A : Args.slice(ArgIx))
CheckArrayAccess(A);
}
return Invalid;
}
static void DiagnoseCalleeStaticArrayParam(Sema &S, ParmVarDecl *PVD) {
TypeLoc TL = PVD->getTypeSourceInfo()->getTypeLoc();
if (DecayedTypeLoc DTL = TL.getAs<DecayedTypeLoc>())
TL = DTL.getOriginalLoc();
if (ArrayTypeLoc ATL = TL.getAs<ArrayTypeLoc>())
S.Diag(PVD->getLocation(), diag::note_callee_static_array)
<< ATL.getLocalSourceRange();
}
/// CheckStaticArrayArgument - If the given argument corresponds to a static
/// array parameter, check that it is non-null, and that if it is formed by
/// array-to-pointer decay, the underlying array is sufficiently large.
///
/// C99 6.7.5.3p7: If the keyword static also appears within the [ and ] of the
/// array type derivation, then for each call to the function, the value of the
/// corresponding actual argument shall provide access to the first element of
/// an array with at least as many elements as specified by the size expression.
void
Sema::CheckStaticArrayArgument(SourceLocation CallLoc,
ParmVarDecl *Param,
const Expr *ArgExpr) {
// Static array parameters are not supported in C++.
if (!Param || getLangOpts().CPlusPlus)
return;
QualType OrigTy = Param->getOriginalType();
const ArrayType *AT = Context.getAsArrayType(OrigTy);
if (!AT || AT->getSizeModifier() != ArrayType::Static)
return;
if (ArgExpr->isNullPointerConstant(Context,
Expr::NPC_NeverValueDependent)) {
Diag(CallLoc, diag::warn_null_arg) << ArgExpr->getSourceRange();
DiagnoseCalleeStaticArrayParam(*this, Param);
return;
}
const ConstantArrayType *CAT = dyn_cast<ConstantArrayType>(AT);
if (!CAT)
return;
const ConstantArrayType *ArgCAT =
Context.getAsConstantArrayType(ArgExpr->IgnoreParenImpCasts()->getType());
if (!ArgCAT)
return;
if (ArgCAT->getSize().ult(CAT->getSize())) {
Diag(CallLoc, diag::warn_static_array_too_small)
<< ArgExpr->getSourceRange()
<< (unsigned) ArgCAT->getSize().getZExtValue()
<< (unsigned) CAT->getSize().getZExtValue();
DiagnoseCalleeStaticArrayParam(*this, Param);
}
}
/// Given a function expression of unknown-any type, try to rebuild it
/// to have a function type.
static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *fn);
/// Is the given type a placeholder that we need to lower out
/// immediately during argument processing?
static bool isPlaceholderToRemoveAsArg(QualType type) {
// Placeholders are never sugared.
const BuiltinType *placeholder = dyn_cast<BuiltinType>(type);
if (!placeholder) return false;
switch (placeholder->getKind()) {
// Ignore all the non-placeholder types.
#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
case BuiltinType::Id:
#include "clang/Basic/OpenCLImageTypes.def"
#define PLACEHOLDER_TYPE(ID, SINGLETON_ID)
#define BUILTIN_TYPE(ID, SINGLETON_ID) case BuiltinType::ID:
#include "clang/AST/BuiltinTypes.def"
return false;
// We cannot lower out overload sets; they might validly be resolved
// by the call machinery.
case BuiltinType::Overload:
return false;
// Unbridged casts in ARC can be handled in some call positions and
// should be left in place.
case BuiltinType::ARCUnbridgedCast:
return false;
// Pseudo-objects should be converted as soon as possible.
case BuiltinType::PseudoObject:
return true;
// The debugger mode could theoretically but currently does not try
// to resolve unknown-typed arguments based on known parameter types.
case BuiltinType::UnknownAny:
return true;
// These are always invalid as call arguments and should be reported.
case BuiltinType::BoundMember:
case BuiltinType::BuiltinFn:
case BuiltinType::OMPArraySection:
return true;
}
llvm_unreachable("bad builtin type kind");
}
/// Check an argument list for placeholders that we won't try to
/// handle later.
static bool checkArgsForPlaceholders(Sema &S, MultiExprArg args) {
// Apply this processing to all the arguments at once instead of
// dying at the first failure.
bool hasInvalid = false;
for (size_t i = 0, e = args.size(); i != e; i++) {
if (isPlaceholderToRemoveAsArg(args[i]->getType())) {
ExprResult result = S.CheckPlaceholderExpr(args[i]);
if (result.isInvalid()) hasInvalid = true;
else args[i] = result.get();
} else if (hasInvalid) {
(void)S.CorrectDelayedTyposInExpr(args[i]);
}
}
return hasInvalid;
}
/// If a builtin function has a pointer argument with no explicit address
/// space, then it should be able to accept a pointer to any address
/// space as input. In order to do this, we need to replace the
/// standard builtin declaration with one that uses the same address space
/// as the call.
///
/// \returns nullptr If this builtin is not a candidate for a rewrite i.e.
/// it does not contain any pointer arguments without
/// an address space qualifer. Otherwise the rewritten
/// FunctionDecl is returned.
/// TODO: Handle pointer return types.
static FunctionDecl *rewriteBuiltinFunctionDecl(Sema *Sema, ASTContext &Context,
const FunctionDecl *FDecl,
MultiExprArg ArgExprs) {
QualType DeclType = FDecl->getType();
const FunctionProtoType *FT = dyn_cast<FunctionProtoType>(DeclType);
if (!Context.BuiltinInfo.hasPtrArgsOrResult(FDecl->getBuiltinID()) ||
!FT || FT->isVariadic() || ArgExprs.size() != FT->getNumParams())
return nullptr;
bool NeedsNewDecl = false;
unsigned i = 0;
SmallVector<QualType, 8> OverloadParams;
for (QualType ParamType : FT->param_types()) {
// Convert array arguments to pointer to simplify type lookup.
ExprResult ArgRes =
Sema->DefaultFunctionArrayLvalueConversion(ArgExprs[i++]);
if (ArgRes.isInvalid())
return nullptr;
Expr *Arg = ArgRes.get();
QualType ArgType = Arg->getType();
if (!ParamType->isPointerType() ||
ParamType.getQualifiers().hasAddressSpace() ||
!ArgType->isPointerType() ||
!ArgType->getPointeeType().getQualifiers().hasAddressSpace()) {
OverloadParams.push_back(ParamType);
continue;
}
NeedsNewDecl = true;
LangAS AS = ArgType->getPointeeType().getAddressSpace();
QualType PointeeType = ParamType->getPointeeType();
PointeeType = Context.getAddrSpaceQualType(PointeeType, AS);
OverloadParams.push_back(Context.getPointerType(PointeeType));
}
if (!NeedsNewDecl)
return nullptr;
FunctionProtoType::ExtProtoInfo EPI;
QualType OverloadTy = Context.getFunctionType(FT->getReturnType(),
OverloadParams, EPI);
DeclContext *Parent = Context.getTranslationUnitDecl();
FunctionDecl *OverloadDecl = FunctionDecl::Create(Context, Parent,
FDecl->getLocation(),
FDecl->getLocation(),
FDecl->getIdentifier(),
OverloadTy,
/*TInfo=*/nullptr,
SC_Extern, false,
/*hasPrototype=*/true);
SmallVector<ParmVarDecl*, 16> Params;
FT = cast<FunctionProtoType>(OverloadTy);
for (unsigned i = 0, e = FT->getNumParams(); i != e; ++i) {
QualType ParamType = FT->getParamType(i);
ParmVarDecl *Parm =
ParmVarDecl::Create(Context, OverloadDecl, SourceLocation(),
SourceLocation(), nullptr, ParamType,
/*TInfo=*/nullptr, SC_None, nullptr);
Parm->setScopeInfo(0, i);
Params.push_back(Parm);
}
OverloadDecl->setParams(Params);
return OverloadDecl;
}
static void checkDirectCallValidity(Sema &S, const Expr *Fn,
FunctionDecl *Callee,
MultiExprArg ArgExprs) {
// `Callee` (when called with ArgExprs) may be ill-formed. enable_if (and
// similar attributes) really don't like it when functions are called with an
// invalid number of args.
if (S.TooManyArguments(Callee->getNumParams(), ArgExprs.size(),
/*PartialOverloading=*/false) &&
!Callee->isVariadic())
return;
if (Callee->getMinRequiredArguments() > ArgExprs.size())
return;
if (const EnableIfAttr *Attr = S.CheckEnableIf(Callee, ArgExprs, true)) {
S.Diag(Fn->getLocStart(),
isa<CXXMethodDecl>(Callee)
? diag::err_ovl_no_viable_member_function_in_call
: diag::err_ovl_no_viable_function_in_call)
<< Callee << Callee->getSourceRange();
S.Diag(Callee->getLocation(),
diag::note_ovl_candidate_disabled_by_function_cond_attr)
<< Attr->getCond()->getSourceRange() << Attr->getMessage();
return;
}
}
static bool enclosingClassIsRelatedToClassInWhichMembersWereFound(
const UnresolvedMemberExpr *const UME, Sema &S) {
const auto GetFunctionLevelDCIfCXXClass =
[](Sema &S) -> const CXXRecordDecl * {
const DeclContext *const DC = S.getFunctionLevelDeclContext();
if (!DC || !DC->getParent())
return nullptr;
// If the call to some member function was made from within a member
// function body 'M' return return 'M's parent.
if (const auto *MD = dyn_cast<CXXMethodDecl>(DC))
return MD->getParent()->getCanonicalDecl();
// else the call was made from within a default member initializer of a
// class, so return the class.
if (const auto *RD = dyn_cast<CXXRecordDecl>(DC))
return RD->getCanonicalDecl();
return nullptr;
};
// If our DeclContext is neither a member function nor a class (in the
// case of a lambda in a default member initializer), we can't have an
// enclosing 'this'.
const CXXRecordDecl *const CurParentClass = GetFunctionLevelDCIfCXXClass(S);
if (!CurParentClass)
return false;
// The naming class for implicit member functions call is the class in which
// name lookup starts.
const CXXRecordDecl *const NamingClass =
UME->getNamingClass()->getCanonicalDecl();
assert(NamingClass && "Must have naming class even for implicit access");
// If the unresolved member functions were found in a 'naming class' that is
// related (either the same or derived from) to the class that contains the
// member function that itself contained the implicit member access.
return CurParentClass == NamingClass ||
CurParentClass->isDerivedFrom(NamingClass);
}
static void
tryImplicitlyCaptureThisIfImplicitMemberFunctionAccessWithDependentArgs(
Sema &S, const UnresolvedMemberExpr *const UME, SourceLocation CallLoc) {
if (!UME)
return;
LambdaScopeInfo *const CurLSI = S.getCurLambda();
// Only try and implicitly capture 'this' within a C++ Lambda if it hasn't
// already been captured, or if this is an implicit member function call (if
// it isn't, an attempt to capture 'this' should already have been made).
if (!CurLSI || CurLSI->ImpCaptureStyle == CurLSI->ImpCap_None ||
!UME->isImplicitAccess() || CurLSI->isCXXThisCaptured())
return;
// Check if the naming class in which the unresolved members were found is
// related (same as or is a base of) to the enclosing class.
if (!enclosingClassIsRelatedToClassInWhichMembersWereFound(UME, S))
return;
DeclContext *EnclosingFunctionCtx = S.CurContext->getParent()->getParent();
// If the enclosing function is not dependent, then this lambda is
// capture ready, so if we can capture this, do so.
if (!EnclosingFunctionCtx->isDependentContext()) {
// If the current lambda and all enclosing lambdas can capture 'this' -
// then go ahead and capture 'this' (since our unresolved overload set
// contains at least one non-static member function).
if (!S.CheckCXXThisCapture(CallLoc, /*Explcit*/ false, /*Diagnose*/ false))
S.CheckCXXThisCapture(CallLoc);
} else if (S.CurContext->isDependentContext()) {
// ... since this is an implicit member reference, that might potentially
// involve a 'this' capture, mark 'this' for potential capture in
// enclosing lambdas.
if (CurLSI->ImpCaptureStyle != CurLSI->ImpCap_None)
CurLSI->addPotentialThisCapture(CallLoc);
}
}
/// ActOnCallExpr - Handle a call to Fn with the specified array of arguments.
/// This provides the location of the left/right parens and a list of comma
/// locations.
ExprResult Sema::ActOnCallExpr(Scope *Scope, Expr *Fn, SourceLocation LParenLoc,
MultiExprArg ArgExprs, SourceLocation RParenLoc,
Expr *ExecConfig, bool IsExecConfig) {
// Since this might be a postfix expression, get rid of ParenListExprs.
ExprResult Result = MaybeConvertParenListExprToParenExpr(Scope, Fn);
if (Result.isInvalid()) return ExprError();
Fn = Result.get();
if (checkArgsForPlaceholders(*this, ArgExprs))
return ExprError();
if (getLangOpts().CPlusPlus) {
// If this is a pseudo-destructor expression, build the call immediately.
if (isa<CXXPseudoDestructorExpr>(Fn)) {
if (!ArgExprs.empty()) {
// Pseudo-destructor calls should not have any arguments.
Diag(Fn->getLocStart(), diag::err_pseudo_dtor_call_with_args)
<< FixItHint::CreateRemoval(
SourceRange(ArgExprs.front()->getLocStart(),
ArgExprs.back()->getLocEnd()));
}
return new (Context)
CallExpr(Context, Fn, None, Context.VoidTy, VK_RValue, RParenLoc);
}
if (Fn->getType() == Context.PseudoObjectTy) {
ExprResult result = CheckPlaceholderExpr(Fn);
if (result.isInvalid()) return ExprError();
Fn = result.get();
}
// Determine whether this is a dependent call inside a C++ template,
// in which case we won't do any semantic analysis now.
bool Dependent = false;
if (Fn->isTypeDependent())
Dependent = true;
else if (Expr::hasAnyTypeDependentArguments(ArgExprs))
Dependent = true;
if (Dependent) {
if (ExecConfig) {
return new (Context) CUDAKernelCallExpr(
Context, Fn, cast<CallExpr>(ExecConfig), ArgExprs,
Context.DependentTy, VK_RValue, RParenLoc);
} else {
tryImplicitlyCaptureThisIfImplicitMemberFunctionAccessWithDependentArgs(
*this, dyn_cast<UnresolvedMemberExpr>(Fn->IgnoreParens()),
Fn->getLocStart());
return new (Context) CallExpr(
Context, Fn, ArgExprs, Context.DependentTy, VK_RValue, RParenLoc);
}
}
// Determine whether this is a call to an object (C++ [over.call.object]).
if (Fn->getType()->isRecordType())
return BuildCallToObjectOfClassType(Scope, Fn, LParenLoc, ArgExprs,
RParenLoc);
if (Fn->getType() == Context.UnknownAnyTy) {
ExprResult result = rebuildUnknownAnyFunction(*this, Fn);
if (result.isInvalid()) return ExprError();
Fn = result.get();
}
if (Fn->getType() == Context.BoundMemberTy) {
return BuildCallToMemberFunction(Scope, Fn, LParenLoc, ArgExprs,
RParenLoc);
}
}
// Check for overloaded calls. This can happen even in C due to extensions.
if (Fn->getType() == Context.OverloadTy) {
OverloadExpr::FindResult find = OverloadExpr::find(Fn);
// We aren't supposed to apply this logic if there's an '&' involved.
if (!find.HasFormOfMemberPointer) {
if (Expr::hasAnyTypeDependentArguments(ArgExprs))
return new (Context) CallExpr(
Context, Fn, ArgExprs, Context.DependentTy, VK_RValue, RParenLoc);
OverloadExpr *ovl = find.Expression;
if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(ovl))
return BuildOverloadedCallExpr(
Scope, Fn, ULE, LParenLoc, ArgExprs, RParenLoc, ExecConfig,
/*AllowTypoCorrection=*/true, find.IsAddressOfOperand);
return BuildCallToMemberFunction(Scope, Fn, LParenLoc, ArgExprs,
RParenLoc);
}
}
// If we're directly calling a function, get the appropriate declaration.
if (Fn->getType() == Context.UnknownAnyTy) {
ExprResult result = rebuildUnknownAnyFunction(*this, Fn);
if (result.isInvalid()) return ExprError();
Fn = result.get();
}
Expr *NakedFn = Fn->IgnoreParens();
bool CallingNDeclIndirectly = false;
NamedDecl *NDecl = nullptr;
if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(NakedFn)) {
if (UnOp->getOpcode() == UO_AddrOf) {
CallingNDeclIndirectly = true;
NakedFn = UnOp->getSubExpr()->IgnoreParens();
}
}
if (isa<DeclRefExpr>(NakedFn)) {
NDecl = cast<DeclRefExpr>(NakedFn)->getDecl();
FunctionDecl *FDecl = dyn_cast<FunctionDecl>(NDecl);
if (FDecl && FDecl->getBuiltinID()) {
// Rewrite the function decl for this builtin by replacing parameters
// with no explicit address space with the address space of the arguments
// in ArgExprs.
if ((FDecl =
rewriteBuiltinFunctionDecl(this, Context, FDecl, ArgExprs))) {
NDecl = FDecl;
Fn = DeclRefExpr::Create(
Context, FDecl->getQualifierLoc(), SourceLocation(), FDecl, false,
SourceLocation(), FDecl->getType(), Fn->getValueKind(), FDecl);
}
}
} else if (isa<MemberExpr>(NakedFn))
NDecl = cast<MemberExpr>(NakedFn)->getMemberDecl();
if (FunctionDecl *FD = dyn_cast_or_null<FunctionDecl>(NDecl)) {
if (CallingNDeclIndirectly &&
!checkAddressOfFunctionIsAvailable(FD, /*Complain=*/true,
Fn->getLocStart()))
return ExprError();
if (getLangOpts().OpenCL && checkOpenCLDisabledDecl(*FD, *Fn))
return ExprError();
checkDirectCallValidity(*this, Fn, FD, ArgExprs);
}
return BuildResolvedCallExpr(Fn, NDecl, LParenLoc, ArgExprs, RParenLoc,
ExecConfig, IsExecConfig);
}
/// ActOnAsTypeExpr - create a new asType (bitcast) from the arguments.
///
/// __builtin_astype( value, dst type )
///
ExprResult Sema::ActOnAsTypeExpr(Expr *E, ParsedType ParsedDestTy,
SourceLocation BuiltinLoc,
SourceLocation RParenLoc) {
ExprValueKind VK = VK_RValue;
ExprObjectKind OK = OK_Ordinary;
QualType DstTy = GetTypeFromParser(ParsedDestTy);
QualType SrcTy = E->getType();
if (Context.getTypeSize(DstTy) != Context.getTypeSize(SrcTy))
return ExprError(Diag(BuiltinLoc,
diag::err_invalid_astype_of_different_size)
<< DstTy
<< SrcTy
<< E->getSourceRange());
return new (Context) AsTypeExpr(E, DstTy, VK, OK, BuiltinLoc, RParenLoc);
}
/// ActOnConvertVectorExpr - create a new convert-vector expression from the
/// provided arguments.
///
/// __builtin_convertvector( value, dst type )
///
ExprResult Sema::ActOnConvertVectorExpr(Expr *E, ParsedType ParsedDestTy,
SourceLocation BuiltinLoc,
SourceLocation RParenLoc) {
TypeSourceInfo *TInfo;
GetTypeFromParser(ParsedDestTy, &TInfo);
return SemaConvertVectorExpr(E, TInfo, BuiltinLoc, RParenLoc);
}
/// BuildResolvedCallExpr - Build a call to a resolved expression,
/// i.e. an expression not of \p OverloadTy. The expression should
/// unary-convert to an expression of function-pointer or
/// block-pointer type.
///
/// \param NDecl the declaration being called, if available
ExprResult
Sema::BuildResolvedCallExpr(Expr *Fn, NamedDecl *NDecl,
SourceLocation LParenLoc,
ArrayRef<Expr *> Args,
SourceLocation RParenLoc,
Expr *Config, bool IsExecConfig) {
FunctionDecl *FDecl = dyn_cast_or_null<FunctionDecl>(NDecl);
unsigned BuiltinID = (FDecl ? FDecl->getBuiltinID() : 0);
// Functions with 'interrupt' attribute cannot be called directly.
if (FDecl && FDecl->hasAttr<AnyX86InterruptAttr>()) {
Diag(Fn->getExprLoc(), diag::err_anyx86_interrupt_called);
return ExprError();
}
// Interrupt handlers don't save off the VFP regs automatically on ARM,
// so there's some risk when calling out to non-interrupt handler functions
// that the callee might not preserve them. This is easy to diagnose here,
// but can be very challenging to debug.
if (auto *Caller = getCurFunctionDecl())
if (Caller->hasAttr<ARMInterruptAttr>()) {
bool VFP = Context.getTargetInfo().hasFeature("vfp");
if (VFP && (!FDecl || !FDecl->hasAttr<ARMInterruptAttr>()))
Diag(Fn->getExprLoc(), diag::warn_arm_interrupt_calling_convention);
}
// Promote the function operand.
// We special-case function promotion here because we only allow promoting
// builtin functions to function pointers in the callee of a call.
ExprResult Result;
if (BuiltinID &&
Fn->getType()->isSpecificBuiltinType(BuiltinType::BuiltinFn)) {
Result = ImpCastExprToType(Fn, Context.getPointerType(FDecl->getType()),
CK_BuiltinFnToFnPtr).get();
} else {
Result = CallExprUnaryConversions(Fn);
}
if (Result.isInvalid())
return ExprError();
Fn = Result.get();
// Make the call expr early, before semantic checks. This guarantees cleanup
// of arguments and function on error.
CallExpr *TheCall;
if (Config)
TheCall = new (Context) CUDAKernelCallExpr(Context, Fn,
cast<CallExpr>(Config), Args,
Context.BoolTy, VK_RValue,
RParenLoc);
else
TheCall = new (Context) CallExpr(Context, Fn, Args, Context.BoolTy,
VK_RValue, RParenLoc);
if (!getLangOpts().CPlusPlus) {
// C cannot always handle TypoExpr nodes in builtin calls and direct
// function calls as their argument checking don't necessarily handle
// dependent types properly, so make sure any TypoExprs have been
// dealt with.
ExprResult Result = CorrectDelayedTyposInExpr(TheCall);
if (!Result.isUsable()) return ExprError();
TheCall = dyn_cast<CallExpr>(Result.get());
if (!TheCall) return Result;
Args = llvm::makeArrayRef(TheCall->getArgs(), TheCall->getNumArgs());
}
// Bail out early if calling a builtin with custom typechecking.
if (BuiltinID && Context.BuiltinInfo.hasCustomTypechecking(BuiltinID))
return CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall);
retry:
const FunctionType *FuncT;
if (const PointerType *PT = Fn->getType()->getAs<PointerType>()) {
// C99 6.5.2.2p1 - "The expression that denotes the called function shall
// have type pointer to function".
FuncT = PT->getPointeeType()->getAs<FunctionType>();
if (!FuncT)
return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function)
<< Fn->getType() << Fn->getSourceRange());
} else if (const BlockPointerType *BPT =
Fn->getType()->getAs<BlockPointerType>()) {
FuncT = BPT->getPointeeType()->castAs<FunctionType>();
} else {
// Handle calls to expressions of unknown-any type.
if (Fn->getType() == Context.UnknownAnyTy) {
ExprResult rewrite = rebuildUnknownAnyFunction(*this, Fn);
if (rewrite.isInvalid()) return ExprError();
Fn = rewrite.get();
TheCall->setCallee(Fn);
goto retry;
}
return ExprError(Diag(LParenLoc, diag::err_typecheck_call_not_function)
<< Fn->getType() << Fn->getSourceRange());
}
if (getLangOpts().CUDA) {
if (Config) {
// CUDA: Kernel calls must be to global functions
if (FDecl && !FDecl->hasAttr<CUDAGlobalAttr>())
return ExprError(Diag(LParenLoc,diag::err_kern_call_not_global_function)
<< FDecl << Fn->getSourceRange());
// CUDA: Kernel function must have 'void' return type
if (!FuncT->getReturnType()->isVoidType())
return ExprError(Diag(LParenLoc, diag::err_kern_type_not_void_return)
<< Fn->getType() << Fn->getSourceRange());
} else {
// CUDA: Calls to global functions must be configured
if (FDecl && FDecl->hasAttr<CUDAGlobalAttr>())
return ExprError(Diag(LParenLoc, diag::err_global_call_not_config)
<< FDecl << Fn->getSourceRange());
}
}
// Check for a valid return type
if (CheckCallReturnType(FuncT->getReturnType(), Fn->getLocStart(), TheCall,
FDecl))
return ExprError();
// We know the result type of the call, set it.
TheCall->setType(FuncT->getCallResultType(Context));
TheCall->setValueKind(Expr::getValueKindForType(FuncT->getReturnType()));
const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FuncT);
if (Proto) {
if (ConvertArgumentsForCall(TheCall, Fn, FDecl, Proto, Args, RParenLoc,
IsExecConfig))
return ExprError();
} else {
assert(isa<FunctionNoProtoType>(FuncT) && "Unknown FunctionType!");
if (FDecl) {
// Check if we have too few/too many template arguments, based
// on our knowledge of the function definition.
const FunctionDecl *Def = nullptr;
if (FDecl->hasBody(Def) && Args.size() != Def->param_size()) {
Proto = Def->getType()->getAs<FunctionProtoType>();
if (!Proto || !(Proto->isVariadic() && Args.size() >= Def->param_size()))
Diag(RParenLoc, diag::warn_call_wrong_number_of_arguments)
<< (Args.size() > Def->param_size()) << FDecl << Fn->getSourceRange();
}
// If the function we're calling isn't a function prototype, but we have
// a function prototype from a prior declaratiom, use that prototype.
if (!FDecl->hasPrototype())
Proto = FDecl->getType()->getAs<FunctionProtoType>();
}
// Promote the arguments (C99 6.5.2.2p6).
for (unsigned i = 0, e = Args.size(); i != e; i++) {
Expr *Arg = Args[i];
if (Proto && i < Proto->getNumParams()) {
InitializedEntity Entity = InitializedEntity::InitializeParameter(
Context, Proto->getParamType(i), Proto->isParamConsumed(i));
ExprResult ArgE =
PerformCopyInitialization(Entity, SourceLocation(), Arg);
if (ArgE.isInvalid())
return true;
Arg = ArgE.getAs<Expr>();
} else {
ExprResult ArgE = DefaultArgumentPromotion(Arg);
if (ArgE.isInvalid())
return true;
Arg = ArgE.getAs<Expr>();
}
if (RequireCompleteType(Arg->getLocStart(),
Arg->getType(),
diag::err_call_incomplete_argument, Arg))
return ExprError();
TheCall->setArg(i, Arg);
}
}
if (CXXMethodDecl *Method = dyn_cast_or_null<CXXMethodDecl>(FDecl))
if (!Method->isStatic())
return ExprError(Diag(LParenLoc, diag::err_member_call_without_object)
<< Fn->getSourceRange());
// Check for sentinels
if (NDecl)
DiagnoseSentinelCalls(NDecl, LParenLoc, Args);
// Do special checking on direct calls to functions.
if (FDecl) {
if (CheckFunctionCall(FDecl, TheCall, Proto))
return ExprError();
if (BuiltinID)
return CheckBuiltinFunctionCall(FDecl, BuiltinID, TheCall);
} else if (NDecl) {
if (CheckPointerCall(NDecl, TheCall, Proto))
return ExprError();
} else {
if (CheckOtherCall(TheCall, Proto))
return ExprError();
}
return MaybeBindToTemporary(TheCall);
}
ExprResult
Sema::ActOnCompoundLiteral(SourceLocation LParenLoc, ParsedType Ty,
SourceLocation RParenLoc, Expr *InitExpr) {
assert(Ty && "ActOnCompoundLiteral(): missing type");
assert(InitExpr && "ActOnCompoundLiteral(): missing expression");
TypeSourceInfo *TInfo;
QualType literalType = GetTypeFromParser(Ty, &TInfo);
if (!TInfo)
TInfo = Context.getTrivialTypeSourceInfo(literalType);
return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, InitExpr);
}
ExprResult
Sema::BuildCompoundLiteralExpr(SourceLocation LParenLoc, TypeSourceInfo *TInfo,
SourceLocation RParenLoc, Expr *LiteralExpr) {
QualType literalType = TInfo->getType();
if (literalType->isArrayType()) {
if (RequireCompleteType(LParenLoc, Context.getBaseElementType(literalType),
diag::err_illegal_decl_array_incomplete_type,
SourceRange(LParenLoc,
LiteralExpr->getSourceRange().getEnd())))
return ExprError();
if (literalType->isVariableArrayType())
return ExprError(Diag(LParenLoc, diag::err_variable_object_no_init)
<< SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd()));
} else if (!literalType->isDependentType() &&
RequireCompleteType(LParenLoc, literalType,
diag::err_typecheck_decl_incomplete_type,
SourceRange(LParenLoc, LiteralExpr->getSourceRange().getEnd())))
return ExprError();
InitializedEntity Entity
= InitializedEntity::InitializeCompoundLiteralInit(TInfo);
InitializationKind Kind
= InitializationKind::CreateCStyleCast(LParenLoc,
SourceRange(LParenLoc, RParenLoc),
/*InitList=*/true);
InitializationSequence InitSeq(*this, Entity, Kind, LiteralExpr);
ExprResult Result = InitSeq.Perform(*this, Entity, Kind, LiteralExpr,
&literalType);
if (Result.isInvalid())
return ExprError();
LiteralExpr = Result.get();
bool isFileScope = !CurContext->isFunctionOrMethod();
if (isFileScope &&
!LiteralExpr->isTypeDependent() &&
!LiteralExpr->isValueDependent() &&
!literalType->isDependentType()) { // 6.5.2.5p3
if (CheckForConstantInitializer(LiteralExpr, literalType))
return ExprError();
}
// In C, compound literals are l-values for some reason.
// For GCC compatibility, in C++, file-scope array compound literals with
// constant initializers are also l-values, and compound literals are
// otherwise prvalues.
//
// (GCC also treats C++ list-initialized file-scope array prvalues with
// constant initializers as l-values, but that's non-conforming, so we don't
// follow it there.)
//
// FIXME: It would be better to handle the lvalue cases as materializing and
// lifetime-extending a temporary object, but our materialized temporaries
// representation only supports lifetime extension from a variable, not "out
// of thin air".
// FIXME: For C++, we might want to instead lifetime-extend only if a pointer
// is bound to the result of applying array-to-pointer decay to the compound
// literal.
// FIXME: GCC supports compound literals of reference type, which should
// obviously have a value kind derived from the kind of reference involved.
ExprValueKind VK =
(getLangOpts().CPlusPlus && !(isFileScope && literalType->isArrayType()))
? VK_RValue
: VK_LValue;
return MaybeBindToTemporary(
new (Context) CompoundLiteralExpr(LParenLoc, TInfo, literalType,
VK, LiteralExpr, isFileScope));
}
ExprResult
Sema::ActOnInitList(SourceLocation LBraceLoc, MultiExprArg InitArgList,
SourceLocation RBraceLoc) {
// Immediately handle non-overload placeholders. Overloads can be
// resolved contextually, but everything else here can't.
for (unsigned I = 0, E = InitArgList.size(); I != E; ++I) {
if (InitArgList[I]->getType()->isNonOverloadPlaceholderType()) {
ExprResult result = CheckPlaceholderExpr(InitArgList[I]);
// Ignore failures; dropping the entire initializer list because
// of one failure would be terrible for indexing/etc.
if (result.isInvalid()) continue;
InitArgList[I] = result.get();
}
}
// Semantic analysis for initializers is done by ActOnDeclarator() and
// CheckInitializer() - it requires knowledge of the object being initialized.
InitListExpr *E = new (Context) InitListExpr(Context, LBraceLoc, InitArgList,
RBraceLoc);
E->setType(Context.VoidTy); // FIXME: just a place holder for now.
return E;
}
/// Do an explicit extend of the given block pointer if we're in ARC.
void Sema::maybeExtendBlockObject(ExprResult &E) {
assert(E.get()->getType()->isBlockPointerType());
assert(E.get()->isRValue());
// Only do this in an r-value context.
if (!getLangOpts().ObjCAutoRefCount) return;
E = ImplicitCastExpr::Create(Context, E.get()->getType(),
CK_ARCExtendBlockObject, E.get(),
/*base path*/ nullptr, VK_RValue);
Cleanup.setExprNeedsCleanups(true);
}
/// Prepare a conversion of the given expression to an ObjC object
/// pointer type.
CastKind Sema::PrepareCastToObjCObjectPointer(ExprResult &E) {
QualType type = E.get()->getType();
if (type->isObjCObjectPointerType()) {
return CK_BitCast;
} else if (type->isBlockPointerType()) {
maybeExtendBlockObject(E);
return CK_BlockPointerToObjCPointerCast;
} else {
assert(type->isPointerType());
return CK_CPointerToObjCPointerCast;
}
}
/// Prepares for a scalar cast, performing all the necessary stages
/// except the final cast and returning the kind required.
CastKind Sema::PrepareScalarCast(ExprResult &Src, QualType DestTy) {
// Both Src and Dest are scalar types, i.e. arithmetic or pointer.
// Also, callers should have filtered out the invalid cases with
// pointers. Everything else should be possible.
QualType SrcTy = Src.get()->getType();
if (Context.hasSameUnqualifiedType(SrcTy, DestTy))
return CK_NoOp;
switch (Type::ScalarTypeKind SrcKind = SrcTy->getScalarTypeKind()) {
case Type::STK_MemberPointer:
llvm_unreachable("member pointer type in C");
case Type::STK_CPointer:
case Type::STK_BlockPointer:
case Type::STK_ObjCObjectPointer:
switch (DestTy->getScalarTypeKind()) {
case Type::STK_CPointer: {
LangAS SrcAS = SrcTy->getPointeeType().getAddressSpace();
LangAS DestAS = DestTy->getPointeeType().getAddressSpace();
if (SrcAS != DestAS)
return CK_AddressSpaceConversion;
return CK_BitCast;
}
case Type::STK_BlockPointer:
return (SrcKind == Type::STK_BlockPointer
? CK_BitCast : CK_AnyPointerToBlockPointerCast);
case Type::STK_ObjCObjectPointer:
if (SrcKind == Type::STK_ObjCObjectPointer)
return CK_BitCast;
if (SrcKind == Type::STK_CPointer)
return CK_CPointerToObjCPointerCast;
maybeExtendBlockObject(Src);
return CK_BlockPointerToObjCPointerCast;
case Type::STK_Bool:
return CK_PointerToBoolean;
case Type::STK_Integral:
return CK_PointerToIntegral;
case Type::STK_Floating:
case Type::STK_FloatingComplex:
case Type::STK_IntegralComplex:
case Type::STK_MemberPointer:
llvm_unreachable("illegal cast from pointer");
}
llvm_unreachable("Should have returned before this");
case Type::STK_Bool: // casting from bool is like casting from an integer
case Type::STK_Integral:
switch (DestTy->getScalarTypeKind()) {
case Type::STK_CPointer:
case Type::STK_ObjCObjectPointer:
case Type::STK_BlockPointer:
if (Src.get()->isNullPointerConstant(Context,
Expr::NPC_ValueDependentIsNull))
return CK_NullToPointer;
return CK_IntegralToPointer;
case Type::STK_Bool:
return CK_IntegralToBoolean;
case Type::STK_Integral:
return CK_IntegralCast;
case Type::STK_Floating:
return CK_IntegralToFloating;
case Type::STK_IntegralComplex:
Src = ImpCastExprToType(Src.get(),
DestTy->castAs<ComplexType>()->getElementType(),
CK_IntegralCast);
return CK_IntegralRealToComplex;
case Type::STK_FloatingComplex:
Src = ImpCastExprToType(Src.get(),
DestTy->castAs<ComplexType>()->getElementType(),
CK_IntegralToFloating);
return CK_FloatingRealToComplex;
case Type::STK_MemberPointer:
llvm_unreachable("member pointer type in C");
}
llvm_unreachable("Should have returned before this");
case Type::STK_Floating:
switch (DestTy->getScalarTypeKind()) {
case Type::STK_Floating:
return CK_FloatingCast;
case Type::STK_Bool:
return CK_FloatingToBoolean;
case Type::STK_Integral:
return CK_FloatingToIntegral;
case Type::STK_FloatingComplex:
Src = ImpCastExprToType(Src.get(),
DestTy->castAs<ComplexType>()->getElementType(),
CK_FloatingCast);
return CK_FloatingRealToComplex;
case Type::STK_IntegralComplex:
Src = ImpCastExprToType(Src.get(),
DestTy->castAs<ComplexType>()->getElementType(),
CK_FloatingToIntegral);
return CK_IntegralRealToComplex;
case Type::STK_CPointer:
case Type::STK_ObjCObjectPointer:
case Type::STK_BlockPointer:
llvm_unreachable("valid float->pointer cast?");
case Type::STK_MemberPointer:
llvm_unreachable("member pointer type in C");
}
llvm_unreachable("Should have returned before this");
case Type::STK_FloatingComplex:
switch (DestTy->getScalarTypeKind()) {
case Type::STK_FloatingComplex:
return CK_FloatingComplexCast;
case Type::STK_IntegralComplex:
return CK_FloatingComplexToIntegralComplex;
case Type::STK_Floating: {
QualType ET = SrcTy->castAs<ComplexType>()->getElementType();
if (Context.hasSameType(ET, DestTy))
return CK_FloatingComplexToReal;
Src = ImpCastExprToType(Src.get(), ET, CK_FloatingComplexToReal);
return CK_FloatingCast;
}
case Type::STK_Bool:
return CK_FloatingComplexToBoolean;
case Type::STK_Integral:
Src = ImpCastExprToType(Src.get(),
SrcTy->castAs<ComplexType>()->getElementType(),
CK_FloatingComplexToReal);
return CK_FloatingToIntegral;
case Type::STK_CPointer:
case Type::STK_ObjCObjectPointer:
case Type::STK_BlockPointer:
llvm_unreachable("valid complex float->pointer cast?");
case Type::STK_MemberPointer:
llvm_unreachable("member pointer type in C");
}
llvm_unreachable("Should have returned before this");
case Type::STK_IntegralComplex:
switch (DestTy->getScalarTypeKind()) {
case Type::STK_FloatingComplex:
return CK_IntegralComplexToFloatingComplex;
case Type::STK_IntegralComplex:
return CK_IntegralComplexCast;
case Type::STK_Integral: {
QualType ET = SrcTy->castAs<ComplexType>()->getElementType();
if (Context.hasSameType(ET, DestTy))
return CK_IntegralComplexToReal;
Src = ImpCastExprToType(Src.get(), ET, CK_IntegralComplexToReal);
return CK_IntegralCast;
}
case Type::STK_Bool:
return CK_IntegralComplexToBoolean;
case Type::STK_Floating:
Src = ImpCastExprToType(Src.get(),
SrcTy->castAs<ComplexType>()->getElementType(),
CK_IntegralComplexToReal);
return CK_IntegralToFloating;
case Type::STK_CPointer:
case Type::STK_ObjCObjectPointer:
case Type::STK_BlockPointer:
llvm_unreachable("valid complex int->pointer cast?");
case Type::STK_MemberPointer:
llvm_unreachable("member pointer type in C");
}
llvm_unreachable("Should have returned before this");
}
llvm_unreachable("Unhandled scalar cast");
}
static bool breakDownVectorType(QualType type, uint64_t &len,
QualType &eltType) {
// Vectors are simple.
if (const VectorType *vecType = type->getAs<VectorType>()) {
len = vecType->getNumElements();
eltType = vecType->getElementType();
assert(eltType->isScalarType());
return true;
}
// We allow lax conversion to and from non-vector types, but only if
// they're real types (i.e. non-complex, non-pointer scalar types).
if (!type->isRealType()) return false;
len = 1;
eltType = type;
return true;
}
/// Are the two types lax-compatible vector types? That is, given
/// that one of them is a vector, do they have equal storage sizes,
/// where the storage size is the number of elements times the element
/// size?
///
/// This will also return false if either of the types is neither a
/// vector nor a real type.
bool Sema::areLaxCompatibleVectorTypes(QualType srcTy, QualType destTy) {
assert(destTy->isVectorType() || srcTy->isVectorType());
// Disallow lax conversions between scalars and ExtVectors (these
// conversions are allowed for other vector types because common headers
// depend on them). Most scalar OP ExtVector cases are handled by the
// splat path anyway, which does what we want (convert, not bitcast).
// What this rules out for ExtVectors is crazy things like char4*float.
if (srcTy->isScalarType() && destTy->isExtVectorType()) return false;
if (destTy->isScalarType() && srcTy->isExtVectorType()) return false;
uint64_t srcLen, destLen;
QualType srcEltTy, destEltTy;
if (!breakDownVectorType(srcTy, srcLen, srcEltTy)) return false;
if (!breakDownVectorType(destTy, destLen, destEltTy)) return false;
// ASTContext::getTypeSize will return the size rounded up to a
// power of 2, so instead of using that, we need to use the raw
// element size multiplied by the element count.
uint64_t srcEltSize = Context.getTypeSize(srcEltTy);
uint64_t destEltSize = Context.getTypeSize(destEltTy);
return (srcLen * srcEltSize == destLen * destEltSize);
}
/// Is this a legal conversion between two types, one of which is
/// known to be a vector type?
bool Sema::isLaxVectorConversion(QualType srcTy, QualType destTy) {
assert(destTy->isVectorType() || srcTy->isVectorType());
if (!Context.getLangOpts().LaxVectorConversions)
return false;
return areLaxCompatibleVectorTypes(srcTy, destTy);
}
bool Sema::CheckVectorCast(SourceRange R, QualType VectorTy, QualType Ty,
CastKind &Kind) {
assert(VectorTy->isVectorType() && "Not a vector type!");
if (Ty->isVectorType() || Ty->isIntegralType(Context)) {
if (!areLaxCompatibleVectorTypes(Ty, VectorTy))
return Diag(R.getBegin(),
Ty->isVectorType() ?
diag::err_invalid_conversion_between_vectors :
diag::err_invalid_conversion_between_vector_and_integer)
<< VectorTy << Ty << R;
} else
return Diag(R.getBegin(),
diag::err_invalid_conversion_between_vector_and_scalar)
<< VectorTy << Ty << R;
Kind = CK_BitCast;
return false;
}
ExprResult Sema::prepareVectorSplat(QualType VectorTy, Expr *SplattedExpr) {
QualType DestElemTy = VectorTy->castAs<VectorType>()->getElementType();
if (DestElemTy == SplattedExpr->getType())
return SplattedExpr;
assert(DestElemTy->isFloatingType() ||
DestElemTy->isIntegralOrEnumerationType());
CastKind CK;
if (VectorTy->isExtVectorType() && SplattedExpr->getType()->isBooleanType()) {
// OpenCL requires that we convert `true` boolean expressions to -1, but
// only when splatting vectors.
if (DestElemTy->isFloatingType()) {
// To avoid having to have a CK_BooleanToSignedFloating cast kind, we cast
// in two steps: boolean to signed integral, then to floating.
ExprResult CastExprRes = ImpCastExprToType(SplattedExpr, Context.IntTy,
CK_BooleanToSignedIntegral);
SplattedExpr = CastExprRes.get();
CK = CK_IntegralToFloating;
} else {
CK = CK_BooleanToSignedIntegral;
}
} else {
ExprResult CastExprRes = SplattedExpr;
CK = PrepareScalarCast(CastExprRes, DestElemTy);
if (CastExprRes.isInvalid())
return ExprError();
SplattedExpr = CastExprRes.get();
}
return ImpCastExprToType(SplattedExpr, DestElemTy, CK);
}
ExprResult Sema::CheckExtVectorCast(SourceRange R, QualType DestTy,
Expr *CastExpr, CastKind &Kind) {
assert(DestTy->isExtVectorType() && "Not an extended vector type!");
QualType SrcTy = CastExpr->getType();
// If SrcTy is a VectorType, the total size must match to explicitly cast to
// an ExtVectorType.
// In OpenCL, casts between vectors of different types are not allowed.
// (See OpenCL 6.2).
if (SrcTy->isVectorType()) {
if (!areLaxCompatibleVectorTypes(SrcTy, DestTy) ||
(getLangOpts().OpenCL &&
!Context.hasSameUnqualifiedType(DestTy, SrcTy))) {
Diag(R.getBegin(),diag::err_invalid_conversion_between_ext_vectors)
<< DestTy << SrcTy << R;
return ExprError();
}
Kind = CK_BitCast;
return CastExpr;
}
// All non-pointer scalars can be cast to ExtVector type. The appropriate
// conversion will take place first from scalar to elt type, and then
// splat from elt type to vector.
if (SrcTy->isPointerType())
return Diag(R.getBegin(),
diag::err_invalid_conversion_between_vector_and_scalar)
<< DestTy << SrcTy << R;
Kind = CK_VectorSplat;
return prepareVectorSplat(DestTy, CastExpr);
}
ExprResult
Sema::ActOnCastExpr(Scope *S, SourceLocation LParenLoc,
Declarator &D, ParsedType &Ty,
SourceLocation RParenLoc, Expr *CastExpr) {
assert(!D.isInvalidType() && (CastExpr != nullptr) &&
"ActOnCastExpr(): missing type or expr");
TypeSourceInfo *castTInfo = GetTypeForDeclaratorCast(D, CastExpr->getType());
if (D.isInvalidType())
return ExprError();
if (getLangOpts().CPlusPlus) {
// Check that there are no default arguments (C++ only).
CheckExtraCXXDefaultArguments(D);
} else {
// Make sure any TypoExprs have been dealt with.
ExprResult Res = CorrectDelayedTyposInExpr(CastExpr);
if (!Res.isUsable())
return ExprError();
CastExpr = Res.get();
}
checkUnusedDeclAttributes(D);
QualType castType = castTInfo->getType();
Ty = CreateParsedType(castType, castTInfo);
bool isVectorLiteral = false;
// Check for an altivec or OpenCL literal,
// i.e. all the elements are integer constants.
ParenExpr *PE = dyn_cast<ParenExpr>(CastExpr);
ParenListExpr *PLE = dyn_cast<ParenListExpr>(CastExpr);
if ((getLangOpts().AltiVec || getLangOpts().ZVector || getLangOpts().OpenCL)
&& castType->isVectorType() && (PE || PLE)) {
if (PLE && PLE->getNumExprs() == 0) {
Diag(PLE->getExprLoc(), diag::err_altivec_empty_initializer);
return ExprError();
}
if (PE || PLE->getNumExprs() == 1) {
Expr *E = (PE ? PE->getSubExpr() : PLE->getExpr(0));
if (!E->getType()->isVectorType())
isVectorLiteral = true;
}
else
isVectorLiteral = true;
}
// If this is a vector initializer, '(' type ')' '(' init, ..., init ')'
// then handle it as such.
if (isVectorLiteral)
return BuildVectorLiteral(LParenLoc, RParenLoc, CastExpr, castTInfo);
// If the Expr being casted is a ParenListExpr, handle it specially.
// This is not an AltiVec-style cast, so turn the ParenListExpr into a
// sequence of BinOp comma operators.
if (isa<ParenListExpr>(CastExpr)) {
ExprResult Result = MaybeConvertParenListExprToParenExpr(S, CastExpr);
if (Result.isInvalid()) return ExprError();
CastExpr = Result.get();
}
if (getLangOpts().CPlusPlus && !castType->isVoidType() &&
!getSourceManager().isInSystemMacro(LParenLoc))
Diag(LParenLoc, diag::warn_old_style_cast) << CastExpr->getSourceRange();
CheckTollFreeBridgeCast(castType, CastExpr);
CheckObjCBridgeRelatedCast(castType, CastExpr);
DiscardMisalignedMemberAddress(castType.getTypePtr(), CastExpr);
return BuildCStyleCastExpr(LParenLoc, castTInfo, RParenLoc, CastExpr);
}
ExprResult Sema::BuildVectorLiteral(SourceLocation LParenLoc,
SourceLocation RParenLoc, Expr *E,
TypeSourceInfo *TInfo) {
assert((isa<ParenListExpr>(E) || isa<ParenExpr>(E)) &&
"Expected paren or paren list expression");
Expr **exprs;
unsigned numExprs;
Expr *subExpr;
SourceLocation LiteralLParenLoc, LiteralRParenLoc;
if (ParenListExpr *PE = dyn_cast<ParenListExpr>(E)) {
LiteralLParenLoc = PE->getLParenLoc();
LiteralRParenLoc = PE->getRParenLoc();
exprs = PE->getExprs();
numExprs = PE->getNumExprs();
} else { // isa<ParenExpr> by assertion at function entrance
LiteralLParenLoc = cast<ParenExpr>(E)->getLParen();
LiteralRParenLoc = cast<ParenExpr>(E)->getRParen();
subExpr = cast<ParenExpr>(E)->getSubExpr();
exprs = &subExpr;
numExprs = 1;
}
QualType Ty = TInfo->getType();
assert(Ty->isVectorType() && "Expected vector type");
SmallVector<Expr *, 8> initExprs;
const VectorType *VTy = Ty->getAs<VectorType>();
unsigned numElems = Ty->getAs<VectorType>()->getNumElements();
// '(...)' form of vector initialization in AltiVec: the number of
// initializers must be one or must match the size of the vector.
// If a single value is specified in the initializer then it will be
// replicated to all the components of the vector
if (VTy->getVectorKind() == VectorType::AltiVecVector) {
// The number of initializers must be one or must match the size of the
// vector. If a single value is specified in the initializer then it will
// be replicated to all the components of the vector
if (numExprs == 1) {
QualType ElemTy = Ty->getAs<VectorType>()->getElementType();
ExprResult Literal = DefaultLvalueConversion(exprs[0]);
if (Literal.isInvalid())
return ExprError();
Literal = ImpCastExprToType(Literal.get(), ElemTy,
PrepareScalarCast(Literal, ElemTy));
return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.get());
}
else if (numExprs < numElems) {
Diag(E->getExprLoc(),
diag::err_incorrect_number_of_vector_initializers);
return ExprError();
}
else
initExprs.append(exprs, exprs + numExprs);
}
else {
// For OpenCL, when the number of initializers is a single value,
// it will be replicated to all components of the vector.
if (getLangOpts().OpenCL &&
VTy->getVectorKind() == VectorType::GenericVector &&
numExprs == 1) {
QualType ElemTy = Ty->getAs<VectorType>()->getElementType();
ExprResult Literal = DefaultLvalueConversion(exprs[0]);
if (Literal.isInvalid())
return ExprError();
Literal = ImpCastExprToType(Literal.get(), ElemTy,
PrepareScalarCast(Literal, ElemTy));
return BuildCStyleCastExpr(LParenLoc, TInfo, RParenLoc, Literal.get());
}
initExprs.append(exprs, exprs + numExprs);
}
// FIXME: This means that pretty-printing the final AST will produce curly
// braces instead of the original commas.
InitListExpr *initE = new (Context) InitListExpr(Context, LiteralLParenLoc,
initExprs, LiteralRParenLoc);
initE->setType(Ty);
return BuildCompoundLiteralExpr(LParenLoc, TInfo, RParenLoc, initE);
}
/// This is not an AltiVec-style cast or or C++ direct-initialization, so turn
/// the ParenListExpr into a sequence of comma binary operators.
ExprResult
Sema::MaybeConvertParenListExprToParenExpr(Scope *S, Expr *OrigExpr) {
ParenListExpr *E = dyn_cast<ParenListExpr>(OrigExpr);
if (!E)
return OrigExpr;
ExprResult Result(E->getExpr(0));
for (unsigned i = 1, e = E->getNumExprs(); i != e && !Result.isInvalid(); ++i)
Result = ActOnBinOp(S, E->getExprLoc(), tok::comma, Result.get(),
E->getExpr(i));
if (Result.isInvalid()) return ExprError();
return ActOnParenExpr(E->getLParenLoc(), E->getRParenLoc(), Result.get());
}
ExprResult Sema::ActOnParenListExpr(SourceLocation L,
SourceLocation R,
MultiExprArg Val) {
Expr *expr = new (Context) ParenListExpr(Context, L, Val, R);
return expr;
}
/// Emit a specialized diagnostic when one expression is a null pointer
/// constant and the other is not a pointer. Returns true if a diagnostic is
/// emitted.
bool Sema::DiagnoseConditionalForNull(Expr *LHSExpr, Expr *RHSExpr,
SourceLocation QuestionLoc) {
Expr *NullExpr = LHSExpr;
Expr *NonPointerExpr = RHSExpr;
Expr::NullPointerConstantKind NullKind =
NullExpr->isNullPointerConstant(Context,
Expr::NPC_ValueDependentIsNotNull);
if (NullKind == Expr::NPCK_NotNull) {
NullExpr = RHSExpr;
NonPointerExpr = LHSExpr;
NullKind =
NullExpr->isNullPointerConstant(Context,
Expr::NPC_ValueDependentIsNotNull);
}
if (NullKind == Expr::NPCK_NotNull)
return false;
if (NullKind == Expr::NPCK_ZeroExpression)
return false;
if (NullKind == Expr::NPCK_ZeroLiteral) {
// In this case, check to make sure that we got here from a "NULL"
// string in the source code.
NullExpr = NullExpr->IgnoreParenImpCasts();
SourceLocation loc = NullExpr->getExprLoc();
if (!findMacroSpelling(loc, "NULL"))
return false;
}
int DiagType = (NullKind == Expr::NPCK_CXX11_nullptr);
Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands_null)
<< NonPointerExpr->getType() << DiagType
<< NonPointerExpr->getSourceRange();
return true;
}
/// Return false if the condition expression is valid, true otherwise.
static bool checkCondition(Sema &S, Expr *Cond, SourceLocation QuestionLoc) {
QualType CondTy = Cond->getType();
// OpenCL v1.1 s6.3.i says the condition cannot be a floating point type.
if (S.getLangOpts().OpenCL && CondTy->isFloatingType()) {
S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_nonfloat)
<< CondTy << Cond->getSourceRange();
return true;
}
// C99 6.5.15p2
if (CondTy->isScalarType()) return false;
S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_scalar)
<< CondTy << Cond->getSourceRange();
return true;
}
/// Handle when one or both operands are void type.
static QualType checkConditionalVoidType(Sema &S, ExprResult &LHS,
ExprResult &RHS) {
Expr *LHSExpr = LHS.get();
Expr *RHSExpr = RHS.get();
if (!LHSExpr->getType()->isVoidType())
S.Diag(RHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void)
<< RHSExpr->getSourceRange();
if (!RHSExpr->getType()->isVoidType())
S.Diag(LHSExpr->getLocStart(), diag::ext_typecheck_cond_one_void)
<< LHSExpr->getSourceRange();
LHS = S.ImpCastExprToType(LHS.get(), S.Context.VoidTy, CK_ToVoid);
RHS = S.ImpCastExprToType(RHS.get(), S.Context.VoidTy, CK_ToVoid);
return S.Context.VoidTy;
}
/// Return false if the NullExpr can be promoted to PointerTy,
/// true otherwise.
static bool checkConditionalNullPointer(Sema &S, ExprResult &NullExpr,
QualType PointerTy) {
if ((!PointerTy->isAnyPointerType() && !PointerTy->isBlockPointerType()) ||
!NullExpr.get()->isNullPointerConstant(S.Context,
Expr::NPC_ValueDependentIsNull))
return true;
NullExpr = S.ImpCastExprToType(NullExpr.get(), PointerTy, CK_NullToPointer);
return false;
}
/// Checks compatibility between two pointers and return the resulting
/// type.
static QualType checkConditionalPointerCompatibility(Sema &S, ExprResult &LHS,
ExprResult &RHS,
SourceLocation Loc) {
QualType LHSTy = LHS.get()->getType();
QualType RHSTy = RHS.get()->getType();
if (S.Context.hasSameType(LHSTy, RHSTy)) {
// Two identical pointers types are always compatible.
return LHSTy;
}
QualType lhptee, rhptee;
// Get the pointee types.
bool IsBlockPointer = false;
if (const BlockPointerType *LHSBTy = LHSTy->getAs<BlockPointerType>()) {
lhptee = LHSBTy->getPointeeType();
rhptee = RHSTy->castAs<BlockPointerType>()->getPointeeType();
IsBlockPointer = true;
} else {
lhptee = LHSTy->castAs<PointerType>()->getPointeeType();
rhptee = RHSTy->castAs<PointerType>()->getPointeeType();
}
// C99 6.5.15p6: If both operands are pointers to compatible types or to
// differently qualified versions of compatible types, the result type is
// a pointer to an appropriately qualified version of the composite
// type.
// Only CVR-qualifiers exist in the standard, and the differently-qualified
// clause doesn't make sense for our extensions. E.g. address space 2 should
// be incompatible with address space 3: they may live on different devices or
// anything.
Qualifiers lhQual = lhptee.getQualifiers();
Qualifiers rhQual = rhptee.getQualifiers();
LangAS ResultAddrSpace = LangAS::Default;
LangAS LAddrSpace = lhQual.getAddressSpace();
LangAS RAddrSpace = rhQual.getAddressSpace();
if (S.getLangOpts().OpenCL) {
// OpenCL v1.1 s6.5 - Conversion between pointers to distinct address
// spaces is disallowed.
if (lhQual.isAddressSpaceSupersetOf(rhQual))
ResultAddrSpace = LAddrSpace;
else if (rhQual.isAddressSpaceSupersetOf(lhQual))
ResultAddrSpace = RAddrSpace;
else {
S.Diag(Loc,
diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
<< LHSTy << RHSTy << 2 << LHS.get()->getSourceRange()
<< RHS.get()->getSourceRange();
return QualType();
}
}
unsigned MergedCVRQual = lhQual.getCVRQualifiers() | rhQual.getCVRQualifiers();
auto LHSCastKind = CK_BitCast, RHSCastKind = CK_BitCast;
lhQual.removeCVRQualifiers();
rhQual.removeCVRQualifiers();
// OpenCL v2.0 specification doesn't extend compatibility of type qualifiers
// (C99 6.7.3) for address spaces. We assume that the check should behave in
// the same manner as it's defined for CVR qualifiers, so for OpenCL two
// qual types are compatible iff
// * corresponded types are compatible
// * CVR qualifiers are equal
// * address spaces are equal
// Thus for conditional operator we merge CVR and address space unqualified
// pointees and if there is a composite type we return a pointer to it with
// merged qualifiers.
if (S.getLangOpts().OpenCL) {
LHSCastKind = LAddrSpace == ResultAddrSpace
? CK_BitCast
: CK_AddressSpaceConversion;
RHSCastKind = RAddrSpace == ResultAddrSpace
? CK_BitCast
: CK_AddressSpaceConversion;
lhQual.removeAddressSpace();
rhQual.removeAddressSpace();
}
lhptee = S.Context.getQualifiedType(lhptee.getUnqualifiedType(), lhQual);
rhptee = S.Context.getQualifiedType(rhptee.getUnqualifiedType(), rhQual);
QualType CompositeTy = S.Context.mergeTypes(lhptee, rhptee);
if (CompositeTy.isNull()) {
// In this situation, we assume void* type. No especially good
// reason, but this is what gcc does, and we do have to pick
// to get a consistent AST.
QualType incompatTy;
incompatTy = S.Context.getPointerType(
S.Context.getAddrSpaceQualType(S.Context.VoidTy, ResultAddrSpace));
LHS = S.ImpCastExprToType(LHS.get(), incompatTy, LHSCastKind);
RHS = S.ImpCastExprToType(RHS.get(), incompatTy, RHSCastKind);
// FIXME: For OpenCL the warning emission and cast to void* leaves a room
// for casts between types with incompatible address space qualifiers.
// For the following code the compiler produces casts between global and
// local address spaces of the corresponded innermost pointees:
// local int *global *a;
// global int *global *b;
// a = (0 ? a : b); // see C99 6.5.16.1.p1.
S.Diag(Loc, diag::ext_typecheck_cond_incompatible_pointers)
<< LHSTy << RHSTy << LHS.get()->getSourceRange()
<< RHS.get()->getSourceRange();
return incompatTy;
}
// The pointer types are compatible.
// In case of OpenCL ResultTy should have the address space qualifier
// which is a superset of address spaces of both the 2nd and the 3rd
// operands of the conditional operator.
QualType ResultTy = [&, ResultAddrSpace]() {
if (S.getLangOpts().OpenCL) {
Qualifiers CompositeQuals = CompositeTy.getQualifiers();
CompositeQuals.setAddressSpace(ResultAddrSpace);
return S.Context
.getQualifiedType(CompositeTy.getUnqualifiedType(), CompositeQuals)
.withCVRQualifiers(MergedCVRQual);
}
return CompositeTy.withCVRQualifiers(MergedCVRQual);
}();
if (IsBlockPointer)
ResultTy = S.Context.getBlockPointerType(ResultTy);
else
ResultTy = S.Context.getPointerType(ResultTy);
LHS = S.ImpCastExprToType(LHS.get(), ResultTy, LHSCastKind);
RHS = S.ImpCastExprToType(RHS.get(), ResultTy, RHSCastKind);
return ResultTy;
}
/// Return the resulting type when the operands are both block pointers.
static QualType checkConditionalBlockPointerCompatibility(Sema &S,
ExprResult &LHS,
ExprResult &RHS,
SourceLocation Loc) {
QualType LHSTy = LHS.get()->getType();
QualType RHSTy = RHS.get()->getType();
if (!LHSTy->isBlockPointerType() || !RHSTy->isBlockPointerType()) {
if (LHSTy->isVoidPointerType() || RHSTy->isVoidPointerType()) {
QualType destType = S.Context.getPointerType(S.Context.VoidTy);
LHS = S.ImpCastExprToType(LHS.get(), destType, CK_BitCast);
RHS = S.ImpCastExprToType(RHS.get(), destType, CK_BitCast);
return destType;
}
S.Diag(Loc, diag::err_typecheck_cond_incompatible_operands)
<< LHSTy << RHSTy << LHS.get()->getSourceRange()
<< RHS.get()->getSourceRange();
return QualType();
}
// We have 2 block pointer types.
return checkConditionalPointerCompatibility(S, LHS, RHS, Loc);
}
/// Return the resulting type when the operands are both pointers.
static QualType
checkConditionalObjectPointersCompatibility(Sema &S, ExprResult &LHS,
ExprResult &RHS,
SourceLocation Loc) {
// get the pointer types
QualType LHSTy = LHS.get()->getType();
QualType RHSTy = RHS.get()->getType();
// get the "pointed to" types
QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType();
QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType();
// ignore qualifiers on void (C99 6.5.15p3, clause 6)
if (lhptee->isVoidType() && rhptee->isIncompleteOrObjectType()) {
// Figure out necessary qualifiers (C99 6.5.15p6)
QualType destPointee
= S.Context.getQualifiedType(lhptee, rhptee.getQualifiers());
QualType destType = S.Context.getPointerType(destPointee);
// Add qualifiers if necessary.
LHS = S.ImpCastExprToType(LHS.get(), destType, CK_NoOp);
// Promote to void*.
RHS = S.ImpCastExprToType(RHS.get(), destType, CK_BitCast);
return destType;
}
if (rhptee->isVoidType() && lhptee->isIncompleteOrObjectType()) {
QualType destPointee
= S.Context.getQualifiedType(rhptee, lhptee.getQualifiers());
QualType destType = S.Context.getPointerType(destPointee);
// Add qualifiers if necessary.
RHS = S.ImpCastExprToType(RHS.get(), destType, CK_NoOp);
// Promote to void*.
LHS = S.ImpCastExprToType(LHS.get(), destType, CK_BitCast);
return destType;
}
return checkConditionalPointerCompatibility(S, LHS, RHS, Loc);
}
/// Return false if the first expression is not an integer and the second
/// expression is not a pointer, true otherwise.
static bool checkPointerIntegerMismatch(Sema &S, ExprResult &Int,
Expr* PointerExpr, SourceLocation Loc,
bool IsIntFirstExpr) {
if (!PointerExpr->getType()->isPointerType() ||
!Int.get()->getType()->isIntegerType())
return false;
Expr *Expr1 = IsIntFirstExpr ? Int.get() : PointerExpr;
Expr *Expr2 = IsIntFirstExpr ? PointerExpr : Int.get();
S.Diag(Loc, diag::ext_typecheck_cond_pointer_integer_mismatch)
<< Expr1->getType() << Expr2->getType()
<< Expr1->getSourceRange() << Expr2->getSourceRange();
Int = S.ImpCastExprToType(Int.get(), PointerExpr->getType(),
CK_IntegralToPointer);
return true;
}
/// Simple conversion between integer and floating point types.
///
/// Used when handling the OpenCL conditional operator where the
/// condition is a vector while the other operands are scalar.
///
/// OpenCL v1.1 s6.3.i and s6.11.6 together require that the scalar
/// types are either integer or floating type. Between the two
/// operands, the type with the higher rank is defined as the "result
/// type". The other operand needs to be promoted to the same type. No
/// other type promotion is allowed. We cannot use
/// UsualArithmeticConversions() for this purpose, since it always
/// promotes promotable types.
static QualType OpenCLArithmeticConversions(Sema &S, ExprResult &LHS,
ExprResult &RHS,
SourceLocation QuestionLoc) {
LHS = S.DefaultFunctionArrayLvalueConversion(LHS.get());
if (LHS.isInvalid())
return QualType();
RHS = S.DefaultFunctionArrayLvalueConversion(RHS.get());
if (RHS.isInvalid())
return QualType();
// For conversion purposes, we ignore any qualifiers.
// For example, "const float" and "float" are equivalent.
QualType LHSType =
S.Context.getCanonicalType(LHS.get()->getType()).getUnqualifiedType();
QualType RHSType =
S.Context.getCanonicalType(RHS.get()->getType()).getUnqualifiedType();
if (!LHSType->isIntegerType() && !LHSType->isRealFloatingType()) {
S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_int_float)
<< LHSType << LHS.get()->getSourceRange();
return QualType();
}
if (!RHSType->isIntegerType() && !RHSType->isRealFloatingType()) {
S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_int_float)
<< RHSType << RHS.get()->getSourceRange();
return QualType();
}
// If both types are identical, no conversion is needed.
if (LHSType == RHSType)
return LHSType;
// Now handle "real" floating types (i.e. float, double, long double).
if (LHSType->isRealFloatingType() || RHSType->isRealFloatingType())
return handleFloatConversion(S, LHS, RHS, LHSType, RHSType,
/*IsCompAssign = */ false);
// Finally, we have two differing integer types.
return handleIntegerConversion<doIntegralCast, doIntegralCast>
(S, LHS, RHS, LHSType, RHSType, /*IsCompAssign = */ false);
}
/// Convert scalar operands to a vector that matches the
/// condition in length.
///
/// Used when handling the OpenCL conditional operator where the
/// condition is a vector while the other operands are scalar.
///
/// We first compute the "result type" for the scalar operands
/// according to OpenCL v1.1 s6.3.i. Both operands are then converted
/// into a vector of that type where the length matches the condition
/// vector type. s6.11.6 requires that the element types of the result
/// and the condition must have the same number of bits.
static QualType
OpenCLConvertScalarsToVectors(Sema &S, ExprResult &LHS, ExprResult &RHS,
QualType CondTy, SourceLocation QuestionLoc) {
QualType ResTy = OpenCLArithmeticConversions(S, LHS, RHS, QuestionLoc);
if (ResTy.isNull()) return QualType();
const VectorType *CV = CondTy->getAs<VectorType>();
assert(CV);
// Determine the vector result type
unsigned NumElements = CV->getNumElements();
QualType VectorTy = S.Context.getExtVectorType(ResTy, NumElements);
// Ensure that all types have the same number of bits
if (S.Context.getTypeSize(CV->getElementType())
!= S.Context.getTypeSize(ResTy)) {
// Since VectorTy is created internally, it does not pretty print
// with an OpenCL name. Instead, we just print a description.
std::string EleTyName = ResTy.getUnqualifiedType().getAsString();
SmallString<64> Str;
llvm::raw_svector_ostream OS(Str);
OS << "(vector of " << NumElements << " '" << EleTyName << "' values)";
S.Diag(QuestionLoc, diag::err_conditional_vector_element_size)
<< CondTy << OS.str();
return QualType();
}
// Convert operands to the vector result type
LHS = S.ImpCastExprToType(LHS.get(), VectorTy, CK_VectorSplat);
RHS = S.ImpCastExprToType(RHS.get(), VectorTy, CK_VectorSplat);
return VectorTy;
}
/// Return false if this is a valid OpenCL condition vector
static bool checkOpenCLConditionVector(Sema &S, Expr *Cond,
SourceLocation QuestionLoc) {
// OpenCL v1.1 s6.11.6 says the elements of the vector must be of
// integral type.
const VectorType *CondTy = Cond->getType()->getAs<VectorType>();
assert(CondTy);
QualType EleTy = CondTy->getElementType();
if (EleTy->isIntegerType()) return false;
S.Diag(QuestionLoc, diag::err_typecheck_cond_expect_nonfloat)
<< Cond->getType() << Cond->getSourceRange();
return true;
}
/// Return false if the vector condition type and the vector
/// result type are compatible.
///
/// OpenCL v1.1 s6.11.6 requires that both vector types have the same
/// number of elements, and their element types have the same number
/// of bits.
static bool checkVectorResult(Sema &S, QualType CondTy, QualType VecResTy,
SourceLocation QuestionLoc) {
const VectorType *CV = CondTy->getAs<VectorType>();
const VectorType *RV = VecResTy->getAs<VectorType>();
assert(CV && RV);
if (CV->getNumElements() != RV->getNumElements()) {
S.Diag(QuestionLoc, diag::err_conditional_vector_size)
<< CondTy << VecResTy;
return true;
}
QualType CVE = CV->getElementType();
QualType RVE = RV->getElementType();
if (S.Context.getTypeSize(CVE) != S.Context.getTypeSize(RVE)) {
S.Diag(QuestionLoc, diag::err_conditional_vector_element_size)
<< CondTy << VecResTy;
return true;
}
return false;
}
/// Return the resulting type for the conditional operator in
/// OpenCL (aka "ternary selection operator", OpenCL v1.1
/// s6.3.i) when the condition is a vector type.
static QualType
OpenCLCheckVectorConditional(Sema &S, ExprResult &Cond,
ExprResult &LHS, ExprResult &RHS,
SourceLocation QuestionLoc) {
Cond = S.DefaultFunctionArrayLvalueConversion(Cond.get());
if (Cond.isInvalid())
return QualType();
QualType CondTy = Cond.get()->getType();
if (checkOpenCLConditionVector(S, Cond.get(), QuestionLoc))
return QualType();
// If either operand is a vector then find the vector type of the
// result as specified in OpenCL v1.1 s6.3.i.
if (LHS.get()->getType()->isVectorType() ||
RHS.get()->getType()->isVectorType()) {
QualType VecResTy = S.CheckVectorOperands(LHS, RHS, QuestionLoc,
/*isCompAssign*/false,
/*AllowBothBool*/true,
/*AllowBoolConversions*/false);
if (VecResTy.isNull()) return QualType();
// The result type must match the condition type as specified in
// OpenCL v1.1 s6.11.6.
if (checkVectorResult(S, CondTy, VecResTy, QuestionLoc))
return QualType();
return VecResTy;
}
// Both operands are scalar.
return OpenCLConvertScalarsToVectors(S, LHS, RHS, CondTy, QuestionLoc);
}
/// Return true if the Expr is block type
static bool checkBlockType(Sema &S, const Expr *E) {
if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
QualType Ty = CE->getCallee()->getType();
if (Ty->isBlockPointerType()) {
S.Diag(E->getExprLoc(), diag::err_opencl_ternary_with_block);
return true;
}
}
return false;
}
/// Note that LHS is not null here, even if this is the gnu "x ?: y" extension.
/// In that case, LHS = cond.
/// C99 6.5.15
QualType Sema::CheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
ExprResult &RHS, ExprValueKind &VK,
ExprObjectKind &OK,
SourceLocation QuestionLoc) {
ExprResult LHSResult = CheckPlaceholderExpr(LHS.get());
if (!LHSResult.isUsable()) return QualType();
LHS = LHSResult;
ExprResult RHSResult = CheckPlaceholderExpr(RHS.get());
if (!RHSResult.isUsable()) return QualType();
RHS = RHSResult;
// C++ is sufficiently different to merit its own checker.
if (getLangOpts().CPlusPlus)
return CXXCheckConditionalOperands(Cond, LHS, RHS, VK, OK, QuestionLoc);
VK = VK_RValue;
OK = OK_Ordinary;
// The OpenCL operator with a vector condition is sufficiently
// different to merit its own checker.
if (getLangOpts().OpenCL && Cond.get()->getType()->isVectorType())
return OpenCLCheckVectorConditional(*this, Cond, LHS, RHS, QuestionLoc);
// First, check the condition.
Cond = UsualUnaryConversions(Cond.get());
if (Cond.isInvalid())
return QualType();
if (checkCondition(*this, Cond.get(), QuestionLoc))
return QualType();
// Now check the two expressions.
if (LHS.get()->getType()->isVectorType() ||
RHS.get()->getType()->isVectorType())
return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false,
/*AllowBothBool*/true,
/*AllowBoolConversions*/false);
QualType ResTy = UsualArithmeticConversions(LHS, RHS);
if (LHS.isInvalid() || RHS.isInvalid())
return QualType();
QualType LHSTy = LHS.get()->getType();
QualType RHSTy = RHS.get()->getType();
// Diagnose attempts to convert between __float128 and long double where
// such conversions currently can't be handled.
if (unsupportedTypeConversion(*this, LHSTy, RHSTy)) {
Diag(QuestionLoc,
diag::err_typecheck_cond_incompatible_operands) << LHSTy << RHSTy
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
return QualType();
}
// OpenCL v2.0 s6.12.5 - Blocks cannot be used as expressions of the ternary
// selection operator (?:).
if (getLangOpts().OpenCL &&
(checkBlockType(*this, LHS.get()) | checkBlockType(*this, RHS.get()))) {
return QualType();
}
// If both operands have arithmetic type, do the usual arithmetic conversions
// to find a common type: C99 6.5.15p3,5.
if (LHSTy->isArithmeticType() && RHSTy->isArithmeticType()) {
LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
return ResTy;
}
// If both operands are the same structure or union type, the result is that
// type.
if (const RecordType *LHSRT = LHSTy->getAs<RecordType>()) { // C99 6.5.15p3
if (const RecordType *RHSRT = RHSTy->getAs<RecordType>())
if (LHSRT->getDecl() == RHSRT->getDecl())
// "If both the operands have structure or union type, the result has
// that type." This implies that CV qualifiers are dropped.
return LHSTy.getUnqualifiedType();
// FIXME: Type of conditional expression must be complete in C mode.
}
// C99 6.5.15p5: "If both operands have void type, the result has void type."
// The following || allows only one side to be void (a GCC-ism).
if (LHSTy->isVoidType() || RHSTy->isVoidType()) {
return checkConditionalVoidType(*this, LHS, RHS);
}
// C99 6.5.15p6 - "if one operand is a null pointer constant, the result has
// the type of the other operand."
if (!checkConditionalNullPointer(*this, RHS, LHSTy)) return LHSTy;
if (!checkConditionalNullPointer(*this, LHS, RHSTy)) return RHSTy;
// All objective-c pointer type analysis is done here.
QualType compositeType = FindCompositeObjCPointerType(LHS, RHS,
QuestionLoc);
if (LHS.isInvalid() || RHS.isInvalid())
return QualType();
if (!compositeType.isNull())
return compositeType;
// Handle block pointer types.
if (LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType())
return checkConditionalBlockPointerCompatibility(*this, LHS, RHS,
QuestionLoc);
// Check constraints for C object pointers types (C99 6.5.15p3,6).
if (LHSTy->isPointerType() && RHSTy->isPointerType())
return checkConditionalObjectPointersCompatibility(*this, LHS, RHS,
QuestionLoc);
// GCC compatibility: soften pointer/integer mismatch. Note that
// null pointers have been filtered out by this point.
if (checkPointerIntegerMismatch(*this, LHS, RHS.get(), QuestionLoc,
/*isIntFirstExpr=*/true))
return RHSTy;
if (checkPointerIntegerMismatch(*this, RHS, LHS.get(), QuestionLoc,
/*isIntFirstExpr=*/false))
return LHSTy;
// Emit a better diagnostic if one of the expressions is a null pointer
// constant and the other is not a pointer type. In this case, the user most
// likely forgot to take the address of the other expression.
if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
return QualType();
// Otherwise, the operands are not compatible.
Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
<< LHSTy << RHSTy << LHS.get()->getSourceRange()
<< RHS.get()->getSourceRange();
return QualType();
}
/// FindCompositeObjCPointerType - Helper method to find composite type of
/// two objective-c pointer types of the two input expressions.
QualType Sema::FindCompositeObjCPointerType(ExprResult &LHS, ExprResult &RHS,
SourceLocation QuestionLoc) {
QualType LHSTy = LHS.get()->getType();
QualType RHSTy = RHS.get()->getType();
// Handle things like Class and struct objc_class*. Here we case the result
// to the pseudo-builtin, because that will be implicitly cast back to the
// redefinition type if an attempt is made to access its fields.
if (LHSTy->isObjCClassType() &&
(Context.hasSameType(RHSTy, Context.getObjCClassRedefinitionType()))) {
RHS = ImpCastExprToType(RHS.get(), LHSTy, CK_CPointerToObjCPointerCast);
return LHSTy;
}
if (RHSTy->isObjCClassType() &&
(Context.hasSameType(LHSTy, Context.getObjCClassRedefinitionType()))) {
LHS = ImpCastExprToType(LHS.get(), RHSTy, CK_CPointerToObjCPointerCast);
return RHSTy;
}
// And the same for struct objc_object* / id
if (LHSTy->isObjCIdType() &&
(Context.hasSameType(RHSTy, Context.getObjCIdRedefinitionType()))) {
RHS = ImpCastExprToType(RHS.get(), LHSTy, CK_CPointerToObjCPointerCast);
return LHSTy;
}
if (RHSTy->isObjCIdType() &&
(Context.hasSameType(LHSTy, Context.getObjCIdRedefinitionType()))) {
LHS = ImpCastExprToType(LHS.get(), RHSTy, CK_CPointerToObjCPointerCast);
return RHSTy;
}
// And the same for struct objc_selector* / SEL
if (Context.isObjCSelType(LHSTy) &&
(Context.hasSameType(RHSTy, Context.getObjCSelRedefinitionType()))) {
RHS = ImpCastExprToType(RHS.get(), LHSTy, CK_BitCast);
return LHSTy;
}
if (Context.isObjCSelType(RHSTy) &&
(Context.hasSameType(LHSTy, Context.getObjCSelRedefinitionType()))) {
LHS = ImpCastExprToType(LHS.get(), RHSTy, CK_BitCast);
return RHSTy;
}
// Check constraints for Objective-C object pointers types.
if (LHSTy->isObjCObjectPointerType() && RHSTy->isObjCObjectPointerType()) {
if (Context.getCanonicalType(LHSTy) == Context.getCanonicalType(RHSTy)) {
// Two identical object pointer types are always compatible.
return LHSTy;
}
const ObjCObjectPointerType *LHSOPT = LHSTy->castAs<ObjCObjectPointerType>();
const ObjCObjectPointerType *RHSOPT = RHSTy->castAs<ObjCObjectPointerType>();
QualType compositeType = LHSTy;
// If both operands are interfaces and either operand can be
// assigned to the other, use that type as the composite
// type. This allows
// xxx ? (A*) a : (B*) b
// where B is a subclass of A.
//
// Additionally, as for assignment, if either type is 'id'
// allow silent coercion. Finally, if the types are
// incompatible then make sure to use 'id' as the composite
// type so the result is acceptable for sending messages to.
// FIXME: Consider unifying with 'areComparableObjCPointerTypes'.
// It could return the composite type.
if (!(compositeType =
Context.areCommonBaseCompatible(LHSOPT, RHSOPT)).isNull()) {
// Nothing more to do.
} else if (Context.canAssignObjCInterfaces(LHSOPT, RHSOPT)) {
compositeType = RHSOPT->isObjCBuiltinType() ? RHSTy : LHSTy;
} else if (Context.canAssignObjCInterfaces(RHSOPT, LHSOPT)) {
compositeType = LHSOPT->isObjCBuiltinType() ? LHSTy : RHSTy;
} else if ((LHSTy->isObjCQualifiedIdType() ||
RHSTy->isObjCQualifiedIdType()) &&
Context.ObjCQualifiedIdTypesAreCompatible(LHSTy, RHSTy, true)) {
// Need to handle "id<xx>" explicitly.
// GCC allows qualified id and any Objective-C type to devolve to
// id. Currently localizing to here until clear this should be
// part of ObjCQualifiedIdTypesAreCompatible.
compositeType = Context.getObjCIdType();
} else if (LHSTy->isObjCIdType() || RHSTy->isObjCIdType()) {
compositeType = Context.getObjCIdType();
} else {
Diag(QuestionLoc, diag::ext_typecheck_cond_incompatible_operands)
<< LHSTy << RHSTy
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
QualType incompatTy = Context.getObjCIdType();
LHS = ImpCastExprToType(LHS.get(), incompatTy, CK_BitCast);
RHS = ImpCastExprToType(RHS.get(), incompatTy, CK_BitCast);
return incompatTy;
}
// The object pointer types are compatible.
LHS = ImpCastExprToType(LHS.get(), compositeType, CK_BitCast);
RHS = ImpCastExprToType(RHS.get(), compositeType, CK_BitCast);
return compositeType;
}
// Check Objective-C object pointer types and 'void *'
if (LHSTy->isVoidPointerType() && RHSTy->isObjCObjectPointerType()) {
if (getLangOpts().ObjCAutoRefCount) {
// ARC forbids the implicit conversion of object pointers to 'void *',
// so these types are not compatible.
Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
LHS = RHS = true;
return QualType();
}
QualType lhptee = LHSTy->getAs<PointerType>()->getPointeeType();
QualType rhptee = RHSTy->getAs<ObjCObjectPointerType>()->getPointeeType();
QualType destPointee
= Context.getQualifiedType(lhptee, rhptee.getQualifiers());
QualType destType = Context.getPointerType(destPointee);
// Add qualifiers if necessary.
LHS = ImpCastExprToType(LHS.get(), destType, CK_NoOp);
// Promote to void*.
RHS = ImpCastExprToType(RHS.get(), destType, CK_BitCast);
return destType;
}
if (LHSTy->isObjCObjectPointerType() && RHSTy->isVoidPointerType()) {
if (getLangOpts().ObjCAutoRefCount) {
// ARC forbids the implicit conversion of object pointers to 'void *',
// so these types are not compatible.
Diag(QuestionLoc, diag::err_cond_voidptr_arc) << LHSTy << RHSTy
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
LHS = RHS = true;
return QualType();
}
QualType lhptee = LHSTy->getAs<ObjCObjectPointerType>()->getPointeeType();
QualType rhptee = RHSTy->getAs<PointerType>()->getPointeeType();
QualType destPointee
= Context.getQualifiedType(rhptee, lhptee.getQualifiers());
QualType destType = Context.getPointerType(destPointee);
// Add qualifiers if necessary.
RHS = ImpCastExprToType(RHS.get(), destType, CK_NoOp);
// Promote to void*.
LHS = ImpCastExprToType(LHS.get(), destType, CK_BitCast);
return destType;
}
return QualType();
}
/// SuggestParentheses - Emit a note with a fixit hint that wraps
/// ParenRange in parentheses.
static void SuggestParentheses(Sema &Self, SourceLocation Loc,
const PartialDiagnostic &Note,
SourceRange ParenRange) {
SourceLocation EndLoc = Self.getLocForEndOfToken(ParenRange.getEnd());
if (ParenRange.getBegin().isFileID() && ParenRange.getEnd().isFileID() &&
EndLoc.isValid()) {
Self.Diag(Loc, Note)
<< FixItHint::CreateInsertion(ParenRange.getBegin(), "(")
<< FixItHint::CreateInsertion(EndLoc, ")");
} else {
// We can't display the parentheses, so just show the bare note.
Self.Diag(Loc, Note) << ParenRange;
}
}
static bool IsArithmeticOp(BinaryOperatorKind Opc) {
return BinaryOperator::isAdditiveOp(Opc) ||
BinaryOperator::isMultiplicativeOp(Opc) ||
BinaryOperator::isShiftOp(Opc);
}
/// IsArithmeticBinaryExpr - Returns true if E is an arithmetic binary
/// expression, either using a built-in or overloaded operator,
/// and sets *OpCode to the opcode and *RHSExprs to the right-hand side
/// expression.
static bool IsArithmeticBinaryExpr(Expr *E, BinaryOperatorKind *Opcode,
Expr **RHSExprs) {
// Don't strip parenthesis: we should not warn if E is in parenthesis.
E = E->IgnoreImpCasts();
E = E->IgnoreConversionOperator();
E = E->IgnoreImpCasts();
if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(E)) {
E = MTE->GetTemporaryExpr();
E = E->IgnoreImpCasts();
}
// Built-in binary operator.
if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E)) {
if (IsArithmeticOp(OP->getOpcode())) {
*Opcode = OP->getOpcode();
*RHSExprs = OP->getRHS();
return true;
}
}
// Overloaded operator.
if (CXXOperatorCallExpr *Call = dyn_cast<CXXOperatorCallExpr>(E)) {
if (Call->getNumArgs() != 2)
return false;
// Make sure this is really a binary operator that is safe to pass into
// BinaryOperator::getOverloadedOpcode(), e.g. it's not a subscript op.
OverloadedOperatorKind OO = Call->getOperator();
if (OO < OO_Plus || OO > OO_Arrow ||
OO == OO_PlusPlus || OO == OO_MinusMinus)
return false;
BinaryOperatorKind OpKind = BinaryOperator::getOverloadedOpcode(OO);
if (IsArithmeticOp(OpKind)) {
*Opcode = OpKind;
*RHSExprs = Call->getArg(1);
return true;
}
}
return false;
}
/// ExprLooksBoolean - Returns true if E looks boolean, i.e. it has boolean type
/// or is a logical expression such as (x==y) which has int type, but is
/// commonly interpreted as boolean.
static bool ExprLooksBoolean(Expr *E) {
E = E->IgnoreParenImpCasts();
if (E->getType()->isBooleanType())
return true;
if (BinaryOperator *OP = dyn_cast<BinaryOperator>(E))
return OP->isComparisonOp() || OP->isLogicalOp();
if (UnaryOperator *OP = dyn_cast<UnaryOperator>(E))
return OP->getOpcode() == UO_LNot;
if (E->getType()->isPointerType())
return true;
// FIXME: What about overloaded operator calls returning "unspecified boolean
// type"s (commonly pointer-to-members)?
return false;
}
/// DiagnoseConditionalPrecedence - Emit a warning when a conditional operator
/// and binary operator are mixed in a way that suggests the programmer assumed
/// the conditional operator has higher precedence, for example:
/// "int x = a + someBinaryCondition ? 1 : 2".
static void DiagnoseConditionalPrecedence(Sema &Self,
SourceLocation OpLoc,
Expr *Condition,
Expr *LHSExpr,
Expr *RHSExpr) {
BinaryOperatorKind CondOpcode;
Expr *CondRHS;
if (!IsArithmeticBinaryExpr(Condition, &CondOpcode, &CondRHS))
return;
if (!ExprLooksBoolean(CondRHS))
return;
// The condition is an arithmetic binary expression, with a right-
// hand side that looks boolean, so warn.
Self.Diag(OpLoc, diag::warn_precedence_conditional)
<< Condition->getSourceRange()
<< BinaryOperator::getOpcodeStr(CondOpcode);
SuggestParentheses(Self, OpLoc,
Self.PDiag(diag::note_precedence_silence)
<< BinaryOperator::getOpcodeStr(CondOpcode),
SourceRange(Condition->getLocStart(), Condition->getLocEnd()));
SuggestParentheses(Self, OpLoc,
Self.PDiag(diag::note_precedence_conditional_first),
SourceRange(CondRHS->getLocStart(), RHSExpr->getLocEnd()));
}
/// Compute the nullability of a conditional expression.
static QualType computeConditionalNullability(QualType ResTy, bool IsBin,
QualType LHSTy, QualType RHSTy,
ASTContext &Ctx) {
if (!ResTy->isAnyPointerType())
return ResTy;
auto GetNullability = [&Ctx](QualType Ty) {
Optional<NullabilityKind> Kind = Ty->getNullability(Ctx);
if (Kind)
return *Kind;
return NullabilityKind::Unspecified;
};
auto LHSKind = GetNullability(LHSTy), RHSKind = GetNullability(RHSTy);
NullabilityKind MergedKind;
// Compute nullability of a binary conditional expression.
if (IsBin) {
if (LHSKind == NullabilityKind::NonNull)
MergedKind = NullabilityKind::NonNull;
else
MergedKind = RHSKind;
// Compute nullability of a normal conditional expression.
} else {
if (LHSKind == NullabilityKind::Nullable ||
RHSKind == NullabilityKind::Nullable)
MergedKind = NullabilityKind::Nullable;
else if (LHSKind == NullabilityKind::NonNull)
MergedKind = RHSKind;
else if (RHSKind == NullabilityKind::NonNull)
MergedKind = LHSKind;
else
MergedKind = NullabilityKind::Unspecified;
}
// Return if ResTy already has the correct nullability.
if (GetNullability(ResTy) == MergedKind)
return ResTy;
// Strip all nullability from ResTy.
while (ResTy->getNullability(Ctx))
ResTy = ResTy.getSingleStepDesugaredType(Ctx);
// Create a new AttributedType with the new nullability kind.
auto NewAttr = AttributedType::getNullabilityAttrKind(MergedKind);
return Ctx.getAttributedType(NewAttr, ResTy, ResTy);
}
/// ActOnConditionalOp - Parse a ?: operation. Note that 'LHS' may be null
/// in the case of a the GNU conditional expr extension.
ExprResult Sema::ActOnConditionalOp(SourceLocation QuestionLoc,
SourceLocation ColonLoc,
Expr *CondExpr, Expr *LHSExpr,
Expr *RHSExpr) {
if (!getLangOpts().CPlusPlus) {
// C cannot handle TypoExpr nodes in the condition because it
// doesn't handle dependent types properly, so make sure any TypoExprs have
// been dealt with before checking the operands.
ExprResult CondResult = CorrectDelayedTyposInExpr(CondExpr);
ExprResult LHSResult = CorrectDelayedTyposInExpr(LHSExpr);
ExprResult RHSResult = CorrectDelayedTyposInExpr(RHSExpr);
if (!CondResult.isUsable())
return ExprError();
if (LHSExpr) {
if (!LHSResult.isUsable())
return ExprError();
}
if (!RHSResult.isUsable())
return ExprError();
CondExpr = CondResult.get();
LHSExpr = LHSResult.get();
RHSExpr = RHSResult.get();
}
// If this is the gnu "x ?: y" extension, analyze the types as though the LHS
// was the condition.
OpaqueValueExpr *opaqueValue = nullptr;
Expr *commonExpr = nullptr;
if (!LHSExpr) {
commonExpr = CondExpr;
// Lower out placeholder types first. This is important so that we don't
// try to capture a placeholder. This happens in few cases in C++; such
// as Objective-C++'s dictionary subscripting syntax.
if (commonExpr->hasPlaceholderType()) {
ExprResult result = CheckPlaceholderExpr(commonExpr);
if (!result.isUsable()) return ExprError();
commonExpr = result.get();
}
// We usually want to apply unary conversions *before* saving, except
// in the special case of a C++ l-value conditional.
if (!(getLangOpts().CPlusPlus
&& !commonExpr->isTypeDependent()
&& commonExpr->getValueKind() == RHSExpr->getValueKind()
&& commonExpr->isGLValue()
&& commonExpr->isOrdinaryOrBitFieldObject()
&& RHSExpr->isOrdinaryOrBitFieldObject()
&& Context.hasSameType(commonExpr->getType(), RHSExpr->getType()))) {
ExprResult commonRes = UsualUnaryConversions(commonExpr);
if (commonRes.isInvalid())
return ExprError();
commonExpr = commonRes.get();
}
// If the common expression is a class or array prvalue, materialize it
// so that we can safely refer to it multiple times.
if (commonExpr->isRValue() && (commonExpr->getType()->isRecordType() ||
commonExpr->getType()->isArrayType())) {
ExprResult MatExpr = TemporaryMaterializationConversion(commonExpr);
if (MatExpr.isInvalid())
return ExprError();
commonExpr = MatExpr.get();
}
opaqueValue = new (Context) OpaqueValueExpr(commonExpr->getExprLoc(),
commonExpr->getType(),
commonExpr->getValueKind(),
commonExpr->getObjectKind(),
commonExpr);
LHSExpr = CondExpr = opaqueValue;
}
QualType LHSTy = LHSExpr->getType(), RHSTy = RHSExpr->getType();
ExprValueKind VK = VK_RValue;
ExprObjectKind OK = OK_Ordinary;
ExprResult Cond = CondExpr, LHS = LHSExpr, RHS = RHSExpr;
QualType result = CheckConditionalOperands(Cond, LHS, RHS,
VK, OK, QuestionLoc);
if (result.isNull() || Cond.isInvalid() || LHS.isInvalid() ||
RHS.isInvalid())
return ExprError();
DiagnoseConditionalPrecedence(*this, QuestionLoc, Cond.get(), LHS.get(),
RHS.get());
CheckBoolLikeConversion(Cond.get(), QuestionLoc);
result = computeConditionalNullability(result, commonExpr, LHSTy, RHSTy,
Context);
if (!commonExpr)
return new (Context)
ConditionalOperator(Cond.get(), QuestionLoc, LHS.get(), ColonLoc,
RHS.get(), result, VK, OK);
return new (Context) BinaryConditionalOperator(
commonExpr, opaqueValue, Cond.get(), LHS.get(), RHS.get(), QuestionLoc,
ColonLoc, result, VK, OK);
}
// checkPointerTypesForAssignment - This is a very tricky routine (despite
// being closely modeled after the C99 spec:-). The odd characteristic of this
// routine is it effectively iqnores the qualifiers on the top level pointee.
// This circumvents the usual type rules specified in 6.2.7p1 & 6.7.5.[1-3].
// FIXME: add a couple examples in this comment.
static Sema::AssignConvertType
checkPointerTypesForAssignment(Sema &S, QualType LHSType, QualType RHSType) {
assert(LHSType.isCanonical() && "LHS not canonicalized!");
assert(RHSType.isCanonical() && "RHS not canonicalized!");
// get the "pointed to" type (ignoring qualifiers at the top level)
const Type *lhptee, *rhptee;
Qualifiers lhq, rhq;
std::tie(lhptee, lhq) =
cast<PointerType>(LHSType)->getPointeeType().split().asPair();
std::tie(rhptee, rhq) =
cast<PointerType>(RHSType)->getPointeeType().split().asPair();
Sema::AssignConvertType ConvTy = Sema::Compatible;
// C99 6.5.16.1p1: This following citation is common to constraints
// 3 & 4 (below). ...and the type *pointed to* by the left has all the
// qualifiers of the type *pointed to* by the right;
// As a special case, 'non-__weak A *' -> 'non-__weak const *' is okay.
if (lhq.getObjCLifetime() != rhq.getObjCLifetime() &&
lhq.compatiblyIncludesObjCLifetime(rhq)) {
// Ignore lifetime for further calculation.
lhq.removeObjCLifetime();
rhq.removeObjCLifetime();
}
if (!lhq.compatiblyIncludes(rhq)) {
// Treat address-space mismatches as fatal. TODO: address subspaces
if (!lhq.isAddressSpaceSupersetOf(rhq))
ConvTy = Sema::IncompatiblePointerDiscardsQualifiers;
// It's okay to add or remove GC or lifetime qualifiers when converting to
// and from void*.
else if (lhq.withoutObjCGCAttr().withoutObjCLifetime()
.compatiblyIncludes(
rhq.withoutObjCGCAttr().withoutObjCLifetime())
&& (lhptee->isVoidType() || rhptee->isVoidType()))
; // keep old
// Treat lifetime mismatches as fatal.
else if (lhq.getObjCLifetime() != rhq.getObjCLifetime())
ConvTy = Sema::IncompatiblePointerDiscardsQualifiers;
// For GCC/MS compatibility, other qualifier mismatches are treated
// as still compatible in C.
else ConvTy = Sema::CompatiblePointerDiscardsQualifiers;
}
// C99 6.5.16.1p1 (constraint 4): If one operand is a pointer to an object or
// incomplete type and the other is a pointer to a qualified or unqualified
// version of void...
if (lhptee->isVoidType()) {
if (rhptee->isIncompleteOrObjectType())
return ConvTy;
// As an extension, we allow cast to/from void* to function pointer.
assert(rhptee->isFunctionType());
return Sema::FunctionVoidPointer;
}
if (rhptee->isVoidType()) {
if (lhptee->isIncompleteOrObjectType())
return ConvTy;
// As an extension, we allow cast to/from void* to function pointer.
assert(lhptee->isFunctionType());
return Sema::FunctionVoidPointer;
}
// C99 6.5.16.1p1 (constraint 3): both operands are pointers to qualified or
// unqualified versions of compatible types, ...
QualType ltrans = QualType(lhptee, 0), rtrans = QualType(rhptee, 0);
if (!S.Context.typesAreCompatible(ltrans, rtrans)) {
// Check if the pointee types are compatible ignoring the sign.
// We explicitly check for char so that we catch "char" vs
// "unsigned char" on systems where "char" is unsigned.
if (lhptee->isCharType())
ltrans = S.Context.UnsignedCharTy;
else if (lhptee->hasSignedIntegerRepresentation())
ltrans = S.Context.getCorrespondingUnsignedType(ltrans);
if (rhptee->isCharType())
rtrans = S.Context.UnsignedCharTy;
else if (rhptee->hasSignedIntegerRepresentation())
rtrans = S.Context.getCorrespondingUnsignedType(rtrans);
if (ltrans == rtrans) {
// Types are compatible ignoring the sign. Qualifier incompatibility
// takes priority over sign incompatibility because the sign
// warning can be disabled.
if (ConvTy != Sema::Compatible)
return ConvTy;
return Sema::IncompatiblePointerSign;
}
// If we are a multi-level pointer, it's possible that our issue is simply
// one of qualification - e.g. char ** -> const char ** is not allowed. If
// the eventual target type is the same and the pointers have the same
// level of indirection, this must be the issue.
if (isa<PointerType>(lhptee) && isa<PointerType>(rhptee)) {
do {
lhptee = cast<PointerType>(lhptee)->getPointeeType().getTypePtr();
rhptee = cast<PointerType>(rhptee)->getPointeeType().getTypePtr();
} while (isa<PointerType>(lhptee) && isa<PointerType>(rhptee));
if (lhptee == rhptee)
return Sema::IncompatibleNestedPointerQualifiers;
}
// General pointer incompatibility takes priority over qualifiers.
return Sema::IncompatiblePointer;
}
if (!S.getLangOpts().CPlusPlus &&
S.IsFunctionConversion(ltrans, rtrans, ltrans))
return Sema::IncompatiblePointer;
return ConvTy;
}
/// checkBlockPointerTypesForAssignment - This routine determines whether two
/// block pointer types are compatible or whether a block and normal pointer
/// are compatible. It is more restrict than comparing two function pointer
// types.
static Sema::AssignConvertType
checkBlockPointerTypesForAssignment(Sema &S, QualType LHSType,
QualType RHSType) {
assert(LHSType.isCanonical() && "LHS not canonicalized!");
assert(RHSType.isCanonical() && "RHS not canonicalized!");
QualType lhptee, rhptee;
// get the "pointed to" type (ignoring qualifiers at the top level)
lhptee = cast<BlockPointerType>(LHSType)->getPointeeType();
rhptee = cast<BlockPointerType>(RHSType)->getPointeeType();
// In C++, the types have to match exactly.
if (S.getLangOpts().CPlusPlus)
return Sema::IncompatibleBlockPointer;
Sema::AssignConvertType ConvTy = Sema::Compatible;
// For blocks we enforce that qualifiers are identical.
Qualifiers LQuals = lhptee.getLocalQualifiers();
Qualifiers RQuals = rhptee.getLocalQualifiers();
if (S.getLangOpts().OpenCL) {
LQuals.removeAddressSpace();
RQuals.removeAddressSpace();
}
if (LQuals != RQuals)
ConvTy = Sema::CompatiblePointerDiscardsQualifiers;
// FIXME: OpenCL doesn't define the exact compile time semantics for a block
// assignment.
// The current behavior is similar to C++ lambdas. A block might be
// assigned to a variable iff its return type and parameters are compatible
// (C99 6.2.7) with the corresponding return type and parameters of the LHS of
// an assignment. Presumably it should behave in way that a function pointer
// assignment does in C, so for each parameter and return type:
// * CVR and address space of LHS should be a superset of CVR and address
// space of RHS.
// * unqualified types should be compatible.
if (S.getLangOpts().OpenCL) {
if (!S.Context.typesAreBlockPointerCompatible(
S.Context.getQualifiedType(LHSType.getUnqualifiedType(), LQuals),
S.Context.getQualifiedType(RHSType.getUnqualifiedType(), RQuals)))
return Sema::IncompatibleBlockPointer;
} else if (!S.Context.typesAreBlockPointerCompatible(LHSType, RHSType))
return Sema::IncompatibleBlockPointer;
return ConvTy;
}
/// checkObjCPointerTypesForAssignment - Compares two objective-c pointer types
/// for assignment compatibility.
static Sema::AssignConvertType
checkObjCPointerTypesForAssignment(Sema &S, QualType LHSType,
QualType RHSType) {
assert(LHSType.isCanonical() && "LHS was not canonicalized!");
assert(RHSType.isCanonical() && "RHS was not canonicalized!");
if (LHSType->isObjCBuiltinType()) {
// Class is not compatible with ObjC object pointers.
if (LHSType->isObjCClassType() && !RHSType->isObjCBuiltinType() &&
!RHSType->isObjCQualifiedClassType())
return Sema::IncompatiblePointer;
return Sema::Compatible;
}
if (RHSType->isObjCBuiltinType()) {
if (RHSType->isObjCClassType() && !LHSType->isObjCBuiltinType() &&
!LHSType->isObjCQualifiedClassType())
return Sema::IncompatiblePointer;
return Sema::Compatible;
}
QualType lhptee = LHSType->getAs<ObjCObjectPointerType>()->getPointeeType();
QualType rhptee = RHSType->getAs<ObjCObjectPointerType>()->getPointeeType();
if (!lhptee.isAtLeastAsQualifiedAs(rhptee) &&
// make an exception for id<P>
!LHSType->isObjCQualifiedIdType())
return Sema::CompatiblePointerDiscardsQualifiers;
if (S.Context.typesAreCompatible(LHSType, RHSType))
return Sema::Compatible;
if (LHSType->isObjCQualifiedIdType() || RHSType->isObjCQualifiedIdType())
return Sema::IncompatibleObjCQualifiedId;
return Sema::IncompatiblePointer;
}
Sema::AssignConvertType
Sema::CheckAssignmentConstraints(SourceLocation Loc,
QualType LHSType, QualType RHSType) {
// Fake up an opaque expression. We don't actually care about what
// cast operations are required, so if CheckAssignmentConstraints
// adds casts to this they'll be wasted, but fortunately that doesn't
// usually happen on valid code.
OpaqueValueExpr RHSExpr(Loc, RHSType, VK_RValue);
ExprResult RHSPtr = &RHSExpr;
CastKind K;
return CheckAssignmentConstraints(LHSType, RHSPtr, K, /*ConvertRHS=*/false);
}
/// This helper function returns true if QT is a vector type that has element
/// type ElementType.
static bool isVector(QualType QT, QualType ElementType) {
if (const VectorType *VT = QT->getAs<VectorType>())
return VT->getElementType() == ElementType;
return false;
}
/// CheckAssignmentConstraints (C99 6.5.16) - This routine currently
/// has code to accommodate several GCC extensions when type checking
/// pointers. Here are some objectionable examples that GCC considers warnings:
///
/// int a, *pint;
/// short *pshort;
/// struct foo *pfoo;
///
/// pint = pshort; // warning: assignment from incompatible pointer type
/// a = pint; // warning: assignment makes integer from pointer without a cast
/// pint = a; // warning: assignment makes pointer from integer without a cast
/// pint = pfoo; // warning: assignment from incompatible pointer type
///
/// As a result, the code for dealing with pointers is more complex than the
/// C99 spec dictates.
///
/// Sets 'Kind' for any result kind except Incompatible.
Sema::AssignConvertType
Sema::CheckAssignmentConstraints(QualType LHSType, ExprResult &RHS,
CastKind &Kind, bool ConvertRHS) {
QualType RHSType = RHS.get()->getType();
QualType OrigLHSType = LHSType;
// Get canonical types. We're not formatting these types, just comparing
// them.
LHSType = Context.getCanonicalType(LHSType).getUnqualifiedType();
RHSType = Context.getCanonicalType(RHSType).getUnqualifiedType();
// Common case: no conversion required.
if (LHSType == RHSType) {
Kind = CK_NoOp;
return Compatible;
}
// If we have an atomic type, try a non-atomic assignment, then just add an
// atomic qualification step.
if (const AtomicType *AtomicTy = dyn_cast<AtomicType>(LHSType)) {
Sema::AssignConvertType result =
CheckAssignmentConstraints(AtomicTy->getValueType(), RHS, Kind);
if (result != Compatible)
return result;
if (Kind != CK_NoOp && ConvertRHS)
RHS = ImpCastExprToType(RHS.get(), AtomicTy->getValueType(), Kind);
Kind = CK_NonAtomicToAtomic;
return Compatible;
}
// If the left-hand side is a reference type, then we are in a
// (rare!) case where we've allowed the use of references in C,
// e.g., as a parameter type in a built-in function. In this case,
// just make sure that the type referenced is compatible with the
// right-hand side type. The caller is responsible for adjusting
// LHSType so that the resulting expression does not have reference
// type.
if (const ReferenceType *LHSTypeRef = LHSType->getAs<ReferenceType>()) {
if (Context.typesAreCompatible(LHSTypeRef->getPointeeType(), RHSType)) {
Kind = CK_LValueBitCast;
return Compatible;
}
return Incompatible;
}
// Allow scalar to ExtVector assignments, and assignments of an ExtVector type
// to the same ExtVector type.
if (LHSType->isExtVectorType()) {
if (RHSType->isExtVectorType())
return Incompatible;
if (RHSType->isArithmeticType()) {
// CK_VectorSplat does T -> vector T, so first cast to the element type.
if (ConvertRHS)
RHS = prepareVectorSplat(LHSType, RHS.get());
Kind = CK_VectorSplat;
return Compatible;
}
}
// Conversions to or from vector type.
if (LHSType->isVectorType() || RHSType->isVectorType()) {
if (LHSType->isVectorType() && RHSType->isVectorType()) {
// Allow assignments of an AltiVec vector type to an equivalent GCC
// vector type and vice versa
if (Context.areCompatibleVectorTypes(LHSType, RHSType)) {
Kind = CK_BitCast;
return Compatible;
}
// If we are allowing lax vector conversions, and LHS and RHS are both
// vectors, the total size only needs to be the same. This is a bitcast;
// no bits are changed but the result type is different.
if (isLaxVectorConversion(RHSType, LHSType)) {
Kind = CK_BitCast;
return IncompatibleVectors;
}
}
// When the RHS comes from another lax conversion (e.g. binops between
// scalars and vectors) the result is canonicalized as a vector. When the
// LHS is also a vector, the lax is allowed by the condition above. Handle
// the case where LHS is a scalar.
if (LHSType->isScalarType()) {
const VectorType *VecType = RHSType->getAs<VectorType>();
if (VecType && VecType->getNumElements() == 1 &&
isLaxVectorConversion(RHSType, LHSType)) {
ExprResult *VecExpr = &RHS;
*VecExpr = ImpCastExprToType(VecExpr->get(), LHSType, CK_BitCast);
Kind = CK_BitCast;
return Compatible;
}
}
return Incompatible;
}
// Diagnose attempts to convert between __float128 and long double where
// such conversions currently can't be handled.
if (unsupportedTypeConversion(*this, LHSType, RHSType))
return Incompatible;
// Disallow assigning a _Complex to a real type in C++ mode since it simply
// discards the imaginary part.
if (getLangOpts().CPlusPlus && RHSType->getAs<ComplexType>() &&
!LHSType->getAs<ComplexType>())
return Incompatible;
// Arithmetic conversions.
if (LHSType->isArithmeticType() && RHSType->isArithmeticType() &&
!(getLangOpts().CPlusPlus && LHSType->isEnumeralType())) {
if (ConvertRHS)
Kind = PrepareScalarCast(RHS, LHSType);
return Compatible;
}
// Conversions to normal pointers.
if (const PointerType *LHSPointer = dyn_cast<PointerType>(LHSType)) {
// U* -> T*
if (isa<PointerType>(RHSType)) {
LangAS AddrSpaceL = LHSPointer->getPointeeType().getAddressSpace();
LangAS AddrSpaceR = RHSType->getPointeeType().getAddressSpace();
Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
return checkPointerTypesForAssignment(*this, LHSType, RHSType);
}
// int -> T*
if (RHSType->isIntegerType()) {
Kind = CK_IntegralToPointer; // FIXME: null?
return IntToPointer;
}
// C pointers are not compatible with ObjC object pointers,
// with two exceptions:
if (isa<ObjCObjectPointerType>(RHSType)) {
// - conversions to void*
if (LHSPointer->getPointeeType()->isVoidType()) {
Kind = CK_BitCast;
return Compatible;
}
// - conversions from 'Class' to the redefinition type
if (RHSType->isObjCClassType() &&
Context.hasSameType(LHSType,
Context.getObjCClassRedefinitionType())) {
Kind = CK_BitCast;
return Compatible;
}
Kind = CK_BitCast;
return IncompatiblePointer;
}
// U^ -> void*
if (RHSType->getAs<BlockPointerType>()) {
if (LHSPointer->getPointeeType()->isVoidType()) {
LangAS AddrSpaceL = LHSPointer->getPointeeType().getAddressSpace();
LangAS AddrSpaceR = RHSType->getAs<BlockPointerType>()
->getPointeeType()
.getAddressSpace();
Kind =
AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
return Compatible;
}
}
return Incompatible;
}
// Conversions to block pointers.
if (isa<BlockPointerType>(LHSType)) {
// U^ -> T^
if (RHSType->isBlockPointerType()) {
LangAS AddrSpaceL = LHSType->getAs<BlockPointerType>()
->getPointeeType()
.getAddressSpace();
LangAS AddrSpaceR = RHSType->getAs<BlockPointerType>()
->getPointeeType()
.getAddressSpace();
Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
return checkBlockPointerTypesForAssignment(*this, LHSType, RHSType);
}
// int or null -> T^
if (RHSType->isIntegerType()) {
Kind = CK_IntegralToPointer; // FIXME: null
return IntToBlockPointer;
}
// id -> T^
if (getLangOpts().ObjC1 && RHSType->isObjCIdType()) {
Kind = CK_AnyPointerToBlockPointerCast;
return Compatible;
}
// void* -> T^
if (const PointerType *RHSPT = RHSType->getAs<PointerType>())
if (RHSPT->getPointeeType()->isVoidType()) {
Kind = CK_AnyPointerToBlockPointerCast;
return Compatible;
}
return Incompatible;
}
// Conversions to Objective-C pointers.
if (isa<ObjCObjectPointerType>(LHSType)) {
// A* -> B*
if (RHSType->isObjCObjectPointerType()) {
Kind = CK_BitCast;
Sema::AssignConvertType result =
checkObjCPointerTypesForAssignment(*this, LHSType, RHSType);
if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
result == Compatible &&
!CheckObjCARCUnavailableWeakConversion(OrigLHSType, RHSType))
result = IncompatibleObjCWeakRef;
return result;
}
// int or null -> A*
if (RHSType->isIntegerType()) {
Kind = CK_IntegralToPointer; // FIXME: null
return IntToPointer;
}
// In general, C pointers are not compatible with ObjC object pointers,
// with two exceptions:
if (isa<PointerType>(RHSType)) {
Kind = CK_CPointerToObjCPointerCast;
// - conversions from 'void*'
if (RHSType->isVoidPointerType()) {
return Compatible;
}
// - conversions to 'Class' from its redefinition type
if (LHSType->isObjCClassType() &&
Context.hasSameType(RHSType,
Context.getObjCClassRedefinitionType())) {
return Compatible;
}
return IncompatiblePointer;
}
// Only under strict condition T^ is compatible with an Objective-C pointer.
if (RHSType->isBlockPointerType() &&
LHSType->isBlockCompatibleObjCPointerType(Context)) {
if (ConvertRHS)
maybeExtendBlockObject(RHS);
Kind = CK_BlockPointerToObjCPointerCast;
return Compatible;
}
return Incompatible;
}
// Conversions from pointers that are not covered by the above.
if (isa<PointerType>(RHSType)) {
// T* -> _Bool
if (LHSType == Context.BoolTy) {
Kind = CK_PointerToBoolean;
return Compatible;
}
// T* -> int
if (LHSType->isIntegerType()) {
Kind = CK_PointerToIntegral;
return PointerToInt;
}
return Incompatible;
}
// Conversions from Objective-C pointers that are not covered by the above.
if (isa<ObjCObjectPointerType>(RHSType)) {
// T* -> _Bool
if (LHSType == Context.BoolTy) {
Kind = CK_PointerToBoolean;
return Compatible;
}
// T* -> int
if (LHSType->isIntegerType()) {
Kind = CK_PointerToIntegral;
return PointerToInt;
}
return Incompatible;
}
// struct A -> struct B
if (isa<TagType>(LHSType) && isa<TagType>(RHSType)) {
if (Context.typesAreCompatible(LHSType, RHSType)) {
Kind = CK_NoOp;
return Compatible;
}
}
if (LHSType->isSamplerT() && RHSType->isIntegerType()) {
Kind = CK_IntToOCLSampler;
return Compatible;
}
return Incompatible;
}
/// Constructs a transparent union from an expression that is
/// used to initialize the transparent union.
static void ConstructTransparentUnion(Sema &S, ASTContext &C,
ExprResult &EResult, QualType UnionType,
FieldDecl *Field) {
// Build an initializer list that designates the appropriate member
// of the transparent union.
Expr *E = EResult.get();
InitListExpr *Initializer = new (C) InitListExpr(C, SourceLocation(),
E, SourceLocation());
Initializer->setType(UnionType);
Initializer->setInitializedFieldInUnion(Field);
// Build a compound literal constructing a value of the transparent
// union type from this initializer list.
TypeSourceInfo *unionTInfo = C.getTrivialTypeSourceInfo(UnionType);
EResult = new (C) CompoundLiteralExpr(SourceLocation(), unionTInfo, UnionType,
VK_RValue, Initializer, false);
}
Sema::AssignConvertType
Sema::CheckTransparentUnionArgumentConstraints(QualType ArgType,
ExprResult &RHS) {
QualType RHSType = RHS.get()->getType();
// If the ArgType is a Union type, we want to handle a potential
// transparent_union GCC extension.
const RecordType *UT = ArgType->getAsUnionType();
if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>())
return Incompatible;
// The field to initialize within the transparent union.
RecordDecl *UD = UT->getDecl();
FieldDecl *InitField = nullptr;
// It's compatible if the expression matches any of the fields.
for (auto *it : UD->fields()) {
if (it->getType()->isPointerType()) {
// If the transparent union contains a pointer type, we allow:
// 1) void pointer
// 2) null pointer constant
if (RHSType->isPointerType())
if (RHSType->castAs<PointerType>()->getPointeeType()->isVoidType()) {
RHS = ImpCastExprToType(RHS.get(), it->getType(), CK_BitCast);
InitField = it;
break;
}
if (RHS.get()->isNullPointerConstant(Context,
Expr::NPC_ValueDependentIsNull)) {
RHS = ImpCastExprToType(RHS.get(), it->getType(),
CK_NullToPointer);
InitField = it;
break;
}
}
CastKind Kind;
if (CheckAssignmentConstraints(it->getType(), RHS, Kind)
== Compatible) {
RHS = ImpCastExprToType(RHS.get(), it->getType(), Kind);
InitField = it;
break;
}
}
if (!InitField)
return Incompatible;
ConstructTransparentUnion(*this, Context, RHS, ArgType, InitField);
return Compatible;
}
Sema::AssignConvertType
Sema::CheckSingleAssignmentConstraints(QualType LHSType, ExprResult &CallerRHS,
bool Diagnose,
bool DiagnoseCFAudited,
bool ConvertRHS) {
// We need to be able to tell the caller whether we diagnosed a problem, if
// they ask us to issue diagnostics.
assert((ConvertRHS || !Diagnose) && "can't indicate whether we diagnosed");
// If ConvertRHS is false, we want to leave the caller's RHS untouched. Sadly,
// we can't avoid *all* modifications at the moment, so we need some somewhere
// to put the updated value.
ExprResult LocalRHS = CallerRHS;
ExprResult &RHS = ConvertRHS ? CallerRHS : LocalRHS;
if (getLangOpts().CPlusPlus) {
if (!LHSType->isRecordType() && !LHSType->isAtomicType()) {
// C++ 5.17p3: If the left operand is not of class type, the
// expression is implicitly converted (C++ 4) to the
// cv-unqualified type of the left operand.
QualType RHSType = RHS.get()->getType();
if (Diagnose) {
RHS = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(),
AA_Assigning);
} else {
ImplicitConversionSequence ICS =
TryImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(),
/*SuppressUserConversions=*/false,
/*AllowExplicit=*/false,
/*InOverloadResolution=*/false,
/*CStyle=*/false,
/*AllowObjCWritebackConversion=*/false);
if (ICS.isFailure())
return Incompatible;
RHS = PerformImplicitConversion(RHS.get(), LHSType.getUnqualifiedType(),
ICS, AA_Assigning);
}
if (RHS.isInvalid())
return Incompatible;
Sema::AssignConvertType result = Compatible;
if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
!CheckObjCARCUnavailableWeakConversion(LHSType, RHSType))
result = IncompatibleObjCWeakRef;
return result;
}
// FIXME: Currently, we fall through and treat C++ classes like C
// structures.
// FIXME: We also fall through for atomics; not sure what should
// happen there, though.
} else if (RHS.get()->getType() == Context.OverloadTy) {
// As a set of extensions to C, we support overloading on functions. These
// functions need to be resolved here.
DeclAccessPair DAP;
if (FunctionDecl *FD = ResolveAddressOfOverloadedFunction(
RHS.get(), LHSType, /*Complain=*/false, DAP))
RHS = FixOverloadedFunctionReference(RHS.get(), DAP, FD);
else
return Incompatible;
}
// C99 6.5.16.1p1: the left operand is a pointer and the right is
// a null pointer constant.
if ((LHSType->isPointerType() || LHSType->isObjCObjectPointerType() ||
LHSType->isBlockPointerType()) &&
RHS.get()->isNullPointerConstant(Context,
Expr::NPC_ValueDependentIsNull)) {
if (Diagnose || ConvertRHS) {
CastKind Kind;
CXXCastPath Path;
CheckPointerConversion(RHS.get(), LHSType, Kind, Path,
/*IgnoreBaseAccess=*/false, Diagnose);
if (ConvertRHS)
RHS = ImpCastExprToType(RHS.get(), LHSType, Kind, VK_RValue, &Path);
}
return Compatible;
}
// This check seems unnatural, however it is necessary to ensure the proper
// conversion of functions/arrays. If the conversion were done for all
// DeclExpr's (created by ActOnIdExpression), it would mess up the unary
// expressions that suppress this implicit conversion (&, sizeof).
//
// Suppress this for references: C++ 8.5.3p5.
if (!LHSType->isReferenceType()) {
// FIXME: We potentially allocate here even if ConvertRHS is false.
RHS = DefaultFunctionArrayLvalueConversion(RHS.get(), Diagnose);
if (RHS.isInvalid())
return Incompatible;
}
Expr *PRE = RHS.get()->IgnoreParenCasts();
if (Diagnose && isa<ObjCProtocolExpr>(PRE)) {
ObjCProtocolDecl *PDecl = cast<ObjCProtocolExpr>(PRE)->getProtocol();
if (PDecl && !PDecl->hasDefinition()) {
Diag(PRE->getExprLoc(), diag::warn_atprotocol_protocol) << PDecl;
Diag(PDecl->getLocation(), diag::note_entity_declared_at) << PDecl;
}
}
CastKind Kind;
Sema::AssignConvertType result =
CheckAssignmentConstraints(LHSType, RHS, Kind, ConvertRHS);
// C99 6.5.16.1p2: The value of the right operand is converted to the
// type of the assignment expression.
// CheckAssignmentConstraints allows the left-hand side to be a reference,
// so that we can use references in built-in functions even in C.
// The getNonReferenceType() call makes sure that the resulting expression
// does not have reference type.
if (result != Incompatible && RHS.get()->getType() != LHSType) {
QualType Ty = LHSType.getNonLValueExprType(Context);
Expr *E = RHS.get();
// Check for various Objective-C errors. If we are not reporting
// diagnostics and just checking for errors, e.g., during overload
// resolution, return Incompatible to indicate the failure.
if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
CheckObjCConversion(SourceRange(), Ty, E, CCK_ImplicitConversion,
Diagnose, DiagnoseCFAudited) != ACR_okay) {
if (!Diagnose)
return Incompatible;
}
if (getLangOpts().ObjC1 &&
(CheckObjCBridgeRelatedConversions(E->getLocStart(), LHSType,
E->getType(), E, Diagnose) ||
ConversionToObjCStringLiteralCheck(LHSType, E, Diagnose))) {
if (!Diagnose)
return Incompatible;
// Replace the expression with a corrected version and continue so we
// can find further errors.
RHS = E;
return Compatible;
}
if (ConvertRHS)
RHS = ImpCastExprToType(E, Ty, Kind);
}
return result;
}
namespace {
/// The original operand to an operator, prior to the application of the usual
/// arithmetic conversions and converting the arguments of a builtin operator
/// candidate.
struct OriginalOperand {
explicit OriginalOperand(Expr *Op) : Orig(Op), Conversion(nullptr) {
if (auto *MTE = dyn_cast<MaterializeTemporaryExpr>(Op))
Op = MTE->GetTemporaryExpr();
if (auto *BTE = dyn_cast<CXXBindTemporaryExpr>(Op))
Op = BTE->getSubExpr();
if (auto *ICE = dyn_cast<ImplicitCastExpr>(Op)) {
Orig = ICE->getSubExprAsWritten();
Conversion = ICE->getConversionFunction();
}
}
QualType getType() const { return Orig->getType(); }
Expr *Orig;
NamedDecl *Conversion;
};
}
QualType Sema::InvalidOperands(SourceLocation Loc, ExprResult &LHS,
ExprResult &RHS) {
OriginalOperand OrigLHS(LHS.get()), OrigRHS(RHS.get());
Diag(Loc, diag::err_typecheck_invalid_operands)
<< OrigLHS.getType() << OrigRHS.getType()
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
// If a user-defined conversion was applied to either of the operands prior
// to applying the built-in operator rules, tell the user about it.
if (OrigLHS.Conversion) {
Diag(OrigLHS.Conversion->getLocation(),
diag::note_typecheck_invalid_operands_converted)
<< 0 << LHS.get()->getType();
}
if (OrigRHS.Conversion) {
Diag(OrigRHS.Conversion->getLocation(),
diag::note_typecheck_invalid_operands_converted)
<< 1 << RHS.get()->getType();
}
return QualType();
}
// Diagnose cases where a scalar was implicitly converted to a vector and
// diagnose the underlying types. Otherwise, diagnose the error
// as invalid vector logical operands for non-C++ cases.
QualType Sema::InvalidLogicalVectorOperands(SourceLocation Loc, ExprResult &LHS,
ExprResult &RHS) {
QualType LHSType = LHS.get()->IgnoreImpCasts()->getType();
QualType RHSType = RHS.get()->IgnoreImpCasts()->getType();
bool LHSNatVec = LHSType->isVectorType();
bool RHSNatVec = RHSType->isVectorType();
if (!(LHSNatVec && RHSNatVec)) {
Expr *Vector = LHSNatVec ? LHS.get() : RHS.get();
Expr *NonVector = !LHSNatVec ? LHS.get() : RHS.get();
Diag(Loc, diag::err_typecheck_logical_vector_expr_gnu_cpp_restrict)
<< 0 << Vector->getType() << NonVector->IgnoreImpCasts()->getType()
<< Vector->getSourceRange();
return QualType();
}
Diag(Loc, diag::err_typecheck_logical_vector_expr_gnu_cpp_restrict)
<< 1 << LHSType << RHSType << LHS.get()->getSourceRange()
<< RHS.get()->getSourceRange();
return QualType();
}
/// Try to convert a value of non-vector type to a vector type by converting
/// the type to the element type of the vector and then performing a splat.
/// If the language is OpenCL, we only use conversions that promote scalar
/// rank; for C, Obj-C, and C++ we allow any real scalar conversion except
/// for float->int.
///
/// OpenCL V2.0 6.2.6.p2:
/// An error shall occur if any scalar operand type has greater rank
/// than the type of the vector element.
///
/// \param scalar - if non-null, actually perform the conversions
/// \return true if the operation fails (but without diagnosing the failure)
static bool tryVectorConvertAndSplat(Sema &S, ExprResult *scalar,
QualType scalarTy,
QualType vectorEltTy,
QualType vectorTy,
unsigned &DiagID) {
// The conversion to apply to the scalar before splatting it,
// if necessary.
CastKind scalarCast = CK_NoOp;
if (vectorEltTy->isIntegralType(S.Context)) {
if (S.getLangOpts().OpenCL && (scalarTy->isRealFloatingType() ||
(scalarTy->isIntegerType() &&
S.Context.getIntegerTypeOrder(vectorEltTy, scalarTy) < 0))) {
DiagID = diag::err_opencl_scalar_type_rank_greater_than_vector_type;
return true;
}
if (!scalarTy->isIntegralType(S.Context))
return true;
scalarCast = CK_IntegralCast;
} else if (vectorEltTy->isRealFloatingType()) {
if (scalarTy->isRealFloatingType()) {
if (S.getLangOpts().OpenCL &&
S.Context.getFloatingTypeOrder(vectorEltTy, scalarTy) < 0) {
DiagID = diag::err_opencl_scalar_type_rank_greater_than_vector_type;
return true;
}
scalarCast = CK_FloatingCast;
}
else if (scalarTy->isIntegralType(S.Context))
scalarCast = CK_IntegralToFloating;
else
return true;
} else {
return true;
}
// Adjust scalar if desired.
if (scalar) {
if (scalarCast != CK_NoOp)
*scalar = S.ImpCastExprToType(scalar->get(), vectorEltTy, scalarCast);
*scalar = S.ImpCastExprToType(scalar->get(), vectorTy, CK_VectorSplat);
}
return false;
}
/// Convert vector E to a vector with the same number of elements but different
/// element type.
static ExprResult convertVector(Expr *E, QualType ElementType, Sema &S) {
const auto *VecTy = E->getType()->getAs<VectorType>();
assert(VecTy && "Expression E must be a vector");
QualType NewVecTy = S.Context.getVectorType(ElementType,
VecTy->getNumElements(),
VecTy->getVectorKind());
// Look through the implicit cast. Return the subexpression if its type is
// NewVecTy.
if (auto *ICE = dyn_cast<ImplicitCastExpr>(E))
if (ICE->getSubExpr()->getType() == NewVecTy)
return ICE->getSubExpr();
auto Cast = ElementType->isIntegerType() ? CK_IntegralCast : CK_FloatingCast;
return S.ImpCastExprToType(E, NewVecTy, Cast);
}
/// Test if a (constant) integer Int can be casted to another integer type
/// IntTy without losing precision.
static bool canConvertIntToOtherIntTy(Sema &S, ExprResult *Int,
QualType OtherIntTy) {
QualType IntTy = Int->get()->getType().getUnqualifiedType();
// Reject cases where the value of the Int is unknown as that would
// possibly cause truncation, but accept cases where the scalar can be
// demoted without loss of precision.
llvm::APSInt Result;
bool CstInt = Int->get()->EvaluateAsInt(Result, S.Context);
int Order = S.Context.getIntegerTypeOrder(OtherIntTy, IntTy);
bool IntSigned = IntTy->hasSignedIntegerRepresentation();
bool OtherIntSigned = OtherIntTy->hasSignedIntegerRepresentation();
if (CstInt) {
// If the scalar is constant and is of a higher order and has more active
// bits that the vector element type, reject it.
unsigned NumBits = IntSigned
? (Result.isNegative() ? Result.getMinSignedBits()
: Result.getActiveBits())
: Result.getActiveBits();
if (Order < 0 && S.Context.getIntWidth(OtherIntTy) < NumBits)
return true;
// If the signedness of the scalar type and the vector element type
// differs and the number of bits is greater than that of the vector
// element reject it.
return (IntSigned != OtherIntSigned &&
NumBits > S.Context.getIntWidth(OtherIntTy));
}
// Reject cases where the value of the scalar is not constant and it's
// order is greater than that of the vector element type.
return (Order < 0);
}
/// Test if a (constant) integer Int can be casted to floating point type
/// FloatTy without losing precision.
static bool canConvertIntTyToFloatTy(Sema &S, ExprResult *Int,
QualType FloatTy) {
QualType IntTy = Int->get()->getType().getUnqualifiedType();
// Determine if the integer constant can be expressed as a floating point
// number of the appropriate type.
llvm::APSInt Result;
bool CstInt = Int->get()->EvaluateAsInt(Result, S.Context);
uint64_t Bits = 0;
if (CstInt) {
// Reject constants that would be truncated if they were converted to
// the floating point type. Test by simple to/from conversion.
// FIXME: Ideally the conversion to an APFloat and from an APFloat
// could be avoided if there was a convertFromAPInt method
// which could signal back if implicit truncation occurred.
llvm::APFloat Float(S.Context.getFloatTypeSemantics(FloatTy));
Float.convertFromAPInt(Result, IntTy->hasSignedIntegerRepresentation(),
llvm::APFloat::rmTowardZero);
llvm::APSInt ConvertBack(S.Context.getIntWidth(IntTy),
!IntTy->hasSignedIntegerRepresentation());
bool Ignored = false;
Float.convertToInteger(ConvertBack, llvm::APFloat::rmNearestTiesToEven,
&Ignored);
if (Result != ConvertBack)
return true;
} else {
// Reject types that cannot be fully encoded into the mantissa of
// the float.
Bits = S.Context.getTypeSize(IntTy);
unsigned FloatPrec = llvm::APFloat::semanticsPrecision(
S.Context.getFloatTypeSemantics(FloatTy));
if (Bits > FloatPrec)
return true;
}
return false;
}
/// Attempt to convert and splat Scalar into a vector whose types matches
/// Vector following GCC conversion rules. The rule is that implicit
/// conversion can occur when Scalar can be casted to match Vector's element
/// type without causing truncation of Scalar.
static bool tryGCCVectorConvertAndSplat(Sema &S, ExprResult *Scalar,
ExprResult *Vector) {
QualType ScalarTy = Scalar->get()->getType().getUnqualifiedType();
QualType VectorTy = Vector->get()->getType().getUnqualifiedType();
const VectorType *VT = VectorTy->getAs<VectorType>();
assert(!isa<ExtVectorType>(VT) &&
"ExtVectorTypes should not be handled here!");
QualType VectorEltTy = VT->getElementType();
// Reject cases where the vector element type or the scalar element type are
// not integral or floating point types.
if (!VectorEltTy->isArithmeticType() || !ScalarTy->isArithmeticType())
return true;
// The conversion to apply to the scalar before splatting it,
// if necessary.
CastKind ScalarCast = CK_NoOp;
// Accept cases where the vector elements are integers and the scalar is
// an integer.
// FIXME: Notionally if the scalar was a floating point value with a precise
// integral representation, we could cast it to an appropriate integer
// type and then perform the rest of the checks here. GCC will perform
// this conversion in some cases as determined by the input language.
// We should accept it on a language independent basis.
if (VectorEltTy->isIntegralType(S.Context) &&
ScalarTy->isIntegralType(S.Context) &&
S.Context.getIntegerTypeOrder(VectorEltTy, ScalarTy)) {
if (canConvertIntToOtherIntTy(S, Scalar, VectorEltTy))
return true;
ScalarCast = CK_IntegralCast;
} else if (VectorEltTy->isRealFloatingType()) {
if (ScalarTy->isRealFloatingType()) {
// Reject cases where the scalar type is not a constant and has a higher
// Order than the vector element type.
llvm::APFloat Result(0.0);
bool CstScalar = Scalar->get()->EvaluateAsFloat(Result, S.Context);
int Order = S.Context.getFloatingTypeOrder(VectorEltTy, ScalarTy);
if (!CstScalar && Order < 0)
return true;
// If the scalar cannot be safely casted to the vector element type,
// reject it.
if (CstScalar) {
bool Truncated = false;
Result.convert(S.Context.getFloatTypeSemantics(VectorEltTy),
llvm::APFloat::rmNearestTiesToEven, &Truncated);
if (Truncated)
return true;
}
ScalarCast = CK_FloatingCast;
} else if (ScalarTy->isIntegralType(S.Context)) {
if (canConvertIntTyToFloatTy(S, Scalar, VectorEltTy))
return true;
ScalarCast = CK_IntegralToFloating;
} else
return true;
}
// Adjust scalar if desired.
if (Scalar) {
if (ScalarCast != CK_NoOp)
*Scalar = S.ImpCastExprToType(Scalar->get(), VectorEltTy, ScalarCast);
*Scalar = S.ImpCastExprToType(Scalar->get(), VectorTy, CK_VectorSplat);
}
return false;
}
QualType Sema::CheckVectorOperands(ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc, bool IsCompAssign,
bool AllowBothBool,
bool AllowBoolConversions) {
if (!IsCompAssign) {
LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
if (LHS.isInvalid())
return QualType();
}
RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
if (RHS.isInvalid())
return QualType();
// For conversion purposes, we ignore any qualifiers.
// For example, "const float" and "float" are equivalent.
QualType LHSType = LHS.get()->getType().getUnqualifiedType();
QualType RHSType = RHS.get()->getType().getUnqualifiedType();
const VectorType *LHSVecType = LHSType->getAs<VectorType>();
const VectorType *RHSVecType = RHSType->getAs<VectorType>();
assert(LHSVecType || RHSVecType);
// AltiVec-style "vector bool op vector bool" combinations are allowed
// for some operators but not others.
if (!AllowBothBool &&
LHSVecType && LHSVecType->getVectorKind() == VectorType::AltiVecBool &&
RHSVecType && RHSVecType->getVectorKind() == VectorType::AltiVecBool)
return InvalidOperands(Loc, LHS, RHS);
// If the vector types are identical, return.
if (Context.hasSameType(LHSType, RHSType))
return LHSType;
// If we have compatible AltiVec and GCC vector types, use the AltiVec type.
if (LHSVecType && RHSVecType &&
Context.areCompatibleVectorTypes(LHSType, RHSType)) {
if (isa<ExtVectorType>(LHSVecType)) {
RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
return LHSType;
}
if (!IsCompAssign)
LHS = ImpCastExprToType(LHS.get(), RHSType, CK_BitCast);
return RHSType;
}
// AllowBoolConversions says that bool and non-bool AltiVec vectors
// can be mixed, with the result being the non-bool type. The non-bool
// operand must have integer element type.
if (AllowBoolConversions && LHSVecType && RHSVecType &&
LHSVecType->getNumElements() == RHSVecType->getNumElements() &&
(Context.getTypeSize(LHSVecType->getElementType()) ==
Context.getTypeSize(RHSVecType->getElementType()))) {
if (LHSVecType->getVectorKind() == VectorType::AltiVecVector &&
LHSVecType->getElementType()->isIntegerType() &&
RHSVecType->getVectorKind() == VectorType::AltiVecBool) {
RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
return LHSType;
}
if (!IsCompAssign &&
LHSVecType->getVectorKind() == VectorType::AltiVecBool &&
RHSVecType->getVectorKind() == VectorType::AltiVecVector &&
RHSVecType->getElementType()->isIntegerType()) {
LHS = ImpCastExprToType(LHS.get(), RHSType, CK_BitCast);
return RHSType;
}
}
// If there's a vector type and a scalar, try to convert the scalar to
// the vector element type and splat.
unsigned DiagID = diag::err_typecheck_vector_not_convertable;
if (!RHSVecType) {
if (isa<ExtVectorType>(LHSVecType)) {
if (!tryVectorConvertAndSplat(*this, &RHS, RHSType,
LHSVecType->getElementType(), LHSType,
DiagID))
return LHSType;
} else {
if (!tryGCCVectorConvertAndSplat(*this, &RHS, &LHS))
return LHSType;
}
}
if (!LHSVecType) {
if (isa<ExtVectorType>(RHSVecType)) {
if (!tryVectorConvertAndSplat(*this, (IsCompAssign ? nullptr : &LHS),
LHSType, RHSVecType->getElementType(),
RHSType, DiagID))
return RHSType;
} else {
if (LHS.get()->getValueKind() == VK_LValue ||
!tryGCCVectorConvertAndSplat(*this, &LHS, &RHS))
return RHSType;
}
}
// FIXME: The code below also handles conversion between vectors and
// non-scalars, we should break this down into fine grained specific checks
// and emit proper diagnostics.
QualType VecType = LHSVecType ? LHSType : RHSType;
const VectorType *VT = LHSVecType ? LHSVecType : RHSVecType;
QualType OtherType = LHSVecType ? RHSType : LHSType;
ExprResult *OtherExpr = LHSVecType ? &RHS : &LHS;
if (isLaxVectorConversion(OtherType, VecType)) {
// If we're allowing lax vector conversions, only the total (data) size
// needs to be the same. For non compound assignment, if one of the types is
// scalar, the result is always the vector type.
if (!IsCompAssign) {
*OtherExpr = ImpCastExprToType(OtherExpr->get(), VecType, CK_BitCast);
return VecType;
// In a compound assignment, lhs += rhs, 'lhs' is a lvalue src, forbidding
// any implicit cast. Here, the 'rhs' should be implicit casted to 'lhs'
// type. Note that this is already done by non-compound assignments in
// CheckAssignmentConstraints. If it's a scalar type, only bitcast for
// <1 x T> -> T. The result is also a vector type.
} else if (OtherType->isExtVectorType() || OtherType->isVectorType() ||
(OtherType->isScalarType() && VT->getNumElements() == 1)) {
ExprResult *RHSExpr = &RHS;
*RHSExpr = ImpCastExprToType(RHSExpr->get(), LHSType, CK_BitCast);
return VecType;
}
}
// Okay, the expression is invalid.
// If there's a non-vector, non-real operand, diagnose that.
if ((!RHSVecType && !RHSType->isRealType()) ||
(!LHSVecType && !LHSType->isRealType())) {
Diag(Loc, diag::err_typecheck_vector_not_convertable_non_scalar)
<< LHSType << RHSType
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
return QualType();
}
// OpenCL V1.1 6.2.6.p1:
// If the operands are of more than one vector type, then an error shall
// occur. Implicit conversions between vector types are not permitted, per
// section 6.2.1.
if (getLangOpts().OpenCL &&
RHSVecType && isa<ExtVectorType>(RHSVecType) &&
LHSVecType && isa<ExtVectorType>(LHSVecType)) {
Diag(Loc, diag::err_opencl_implicit_vector_conversion) << LHSType
<< RHSType;
return QualType();
}
// If there is a vector type that is not a ExtVector and a scalar, we reach
// this point if scalar could not be converted to the vector's element type
// without truncation.
if ((RHSVecType && !isa<ExtVectorType>(RHSVecType)) ||
(LHSVecType && !isa<ExtVectorType>(LHSVecType))) {
QualType Scalar = LHSVecType ? RHSType : LHSType;
QualType Vector = LHSVecType ? LHSType : RHSType;
unsigned ScalarOrVector = LHSVecType && RHSVecType ? 1 : 0;
Diag(Loc,
diag::err_typecheck_vector_not_convertable_implict_truncation)
<< ScalarOrVector << Scalar << Vector;
return QualType();
}
// Otherwise, use the generic diagnostic.
Diag(Loc, DiagID)
<< LHSType << RHSType
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
return QualType();
}
// checkArithmeticNull - Detect when a NULL constant is used improperly in an
// expression. These are mainly cases where the null pointer is used as an
// integer instead of a pointer.
static void checkArithmeticNull(Sema &S, ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc, bool IsCompare) {
// The canonical way to check for a GNU null is with isNullPointerConstant,
// but we use a bit of a hack here for speed; this is a relatively
// hot path, and isNullPointerConstant is slow.
bool LHSNull = isa<GNUNullExpr>(LHS.get()->IgnoreParenImpCasts());
bool RHSNull = isa<GNUNullExpr>(RHS.get()->IgnoreParenImpCasts());
QualType NonNullType = LHSNull ? RHS.get()->getType() : LHS.get()->getType();
// Avoid analyzing cases where the result will either be invalid (and
// diagnosed as such) or entirely valid and not something to warn about.
if ((!LHSNull && !RHSNull) || NonNullType->isBlockPointerType() ||
NonNullType->isMemberPointerType() || NonNullType->isFunctionType())
return;
// Comparison operations would not make sense with a null pointer no matter
// what the other expression is.
if (!IsCompare) {
S.Diag(Loc, diag::warn_null_in_arithmetic_operation)
<< (LHSNull ? LHS.get()->getSourceRange() : SourceRange())
<< (RHSNull ? RHS.get()->getSourceRange() : SourceRange());
return;
}
// The rest of the operations only make sense with a null pointer
// if the other expression is a pointer.
if (LHSNull == RHSNull || NonNullType->isAnyPointerType() ||
NonNullType->canDecayToPointerType())
return;
S.Diag(Loc, diag::warn_null_in_comparison_operation)
<< LHSNull /* LHS is NULL */ << NonNullType
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
}
static void DiagnoseBadDivideOrRemainderValues(Sema& S, ExprResult &LHS,
ExprResult &RHS,
SourceLocation Loc, bool IsDiv) {
// Check for division/remainder by zero.
llvm::APSInt RHSValue;
if (!RHS.get()->isValueDependent() &&
RHS.get()->EvaluateAsInt(RHSValue, S.Context) && RHSValue == 0)
S.DiagRuntimeBehavior(Loc, RHS.get(),
S.PDiag(diag::warn_remainder_division_by_zero)
<< IsDiv << RHS.get()->getSourceRange());
}
QualType Sema::CheckMultiplyDivideOperands(ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc,
bool IsCompAssign, bool IsDiv) {
checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
if (LHS.get()->getType()->isVectorType() ||
RHS.get()->getType()->isVectorType())
return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
/*AllowBothBool*/getLangOpts().AltiVec,
/*AllowBoolConversions*/false);
QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign);
if (LHS.isInvalid() || RHS.isInvalid())
return QualType();
if (compType.isNull() || !compType->isArithmeticType())
return InvalidOperands(Loc, LHS, RHS);
if (IsDiv)
DiagnoseBadDivideOrRemainderValues(*this, LHS, RHS, Loc, IsDiv);
return compType;
}
QualType Sema::CheckRemainderOperands(
ExprResult &LHS, ExprResult &RHS, SourceLocation Loc, bool IsCompAssign) {
checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
if (LHS.get()->getType()->isVectorType() ||
RHS.get()->getType()->isVectorType()) {
if (LHS.get()->getType()->hasIntegerRepresentation() &&
RHS.get()->getType()->hasIntegerRepresentation())
return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
/*AllowBothBool*/getLangOpts().AltiVec,
/*AllowBoolConversions*/false);
return InvalidOperands(Loc, LHS, RHS);
}
QualType compType = UsualArithmeticConversions(LHS, RHS, IsCompAssign);
if (LHS.isInvalid() || RHS.isInvalid())
return QualType();
if (compType.isNull() || !compType->isIntegerType())
return InvalidOperands(Loc, LHS, RHS);
DiagnoseBadDivideOrRemainderValues(*this, LHS, RHS, Loc, false /* IsDiv */);
return compType;
}
/// Diagnose invalid arithmetic on two void pointers.
static void diagnoseArithmeticOnTwoVoidPointers(Sema &S, SourceLocation Loc,
Expr *LHSExpr, Expr *RHSExpr) {
S.Diag(Loc, S.getLangOpts().CPlusPlus
? diag::err_typecheck_pointer_arith_void_type
: diag::ext_gnu_void_ptr)
<< 1 /* two pointers */ << LHSExpr->getSourceRange()
<< RHSExpr->getSourceRange();
}
/// Diagnose invalid arithmetic on a void pointer.
static void diagnoseArithmeticOnVoidPointer(Sema &S, SourceLocation Loc,
Expr *Pointer) {
S.Diag(Loc, S.getLangOpts().CPlusPlus
? diag::err_typecheck_pointer_arith_void_type
: diag::ext_gnu_void_ptr)
<< 0 /* one pointer */ << Pointer->getSourceRange();
}
/// Diagnose invalid arithmetic on a null pointer.
///
/// If \p IsGNUIdiom is true, the operation is using the 'p = (i8*)nullptr + n'
/// idiom, which we recognize as a GNU extension.
///
static void diagnoseArithmeticOnNullPointer(Sema &S, SourceLocation Loc,
Expr *Pointer, bool IsGNUIdiom) {
if (IsGNUIdiom)
S.Diag(Loc, diag::warn_gnu_null_ptr_arith)
<< Pointer->getSourceRange();
else
S.Diag(Loc, diag::warn_pointer_arith_null_ptr)
<< S.getLangOpts().CPlusPlus << Pointer->getSourceRange();
}
/// Diagnose invalid arithmetic on two function pointers.
static void diagnoseArithmeticOnTwoFunctionPointers(Sema &S, SourceLocation Loc,
Expr *LHS, Expr *RHS) {
assert(LHS->getType()->isAnyPointerType());
assert(RHS->getType()->isAnyPointerType());
S.Diag(Loc, S.getLangOpts().CPlusPlus
? diag::err_typecheck_pointer_arith_function_type
: diag::ext_gnu_ptr_func_arith)
<< 1 /* two pointers */ << LHS->getType()->getPointeeType()
// We only show the second type if it differs from the first.
<< (unsigned)!S.Context.hasSameUnqualifiedType(LHS->getType(),
RHS->getType())
<< RHS->getType()->getPointeeType()
<< LHS->getSourceRange() << RHS->getSourceRange();
}
/// Diagnose invalid arithmetic on a function pointer.
static void diagnoseArithmeticOnFunctionPointer(Sema &S, SourceLocation Loc,
Expr *Pointer) {
assert(Pointer->getType()->isAnyPointerType());
S.Diag(Loc, S.getLangOpts().CPlusPlus
? diag::err_typecheck_pointer_arith_function_type
: diag::ext_gnu_ptr_func_arith)
<< 0 /* one pointer */ << Pointer->getType()->getPointeeType()
<< 0 /* one pointer, so only one type */
<< Pointer->getSourceRange();
}
/// Emit error if Operand is incomplete pointer type
///
/// \returns True if pointer has incomplete type
static bool checkArithmeticIncompletePointerType(Sema &S, SourceLocation Loc,
Expr *Operand) {
QualType ResType = Operand->getType();
if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
ResType = ResAtomicType->getValueType();
assert(ResType->isAnyPointerType() && !ResType->isDependentType());
QualType PointeeTy = ResType->getPointeeType();
return S.RequireCompleteType(Loc, PointeeTy,
diag::err_typecheck_arithmetic_incomplete_type,
PointeeTy, Operand->getSourceRange());
}
/// Check the validity of an arithmetic pointer operand.
///
/// If the operand has pointer type, this code will check for pointer types
/// which are invalid in arithmetic operations. These will be diagnosed
/// appropriately, including whether or not the use is supported as an
/// extension.
///
/// \returns True when the operand is valid to use (even if as an extension).
static bool checkArithmeticOpPointerOperand(Sema &S, SourceLocation Loc,
Expr *Operand) {
QualType ResType = Operand->getType();
if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
ResType = ResAtomicType->getValueType();
if (!ResType->isAnyPointerType()) return true;
QualType PointeeTy = ResType->getPointeeType();
if (PointeeTy->isVoidType()) {
diagnoseArithmeticOnVoidPointer(S, Loc, Operand);
return !S.getLangOpts().CPlusPlus;
}
if (PointeeTy->isFunctionType()) {
diagnoseArithmeticOnFunctionPointer(S, Loc, Operand);
return !S.getLangOpts().CPlusPlus;
}
if (checkArithmeticIncompletePointerType(S, Loc, Operand)) return false;
return true;
}
/// Check the validity of a binary arithmetic operation w.r.t. pointer
/// operands.
///
/// This routine will diagnose any invalid arithmetic on pointer operands much
/// like \see checkArithmeticOpPointerOperand. However, it has special logic
/// for emitting a single diagnostic even for operations where both LHS and RHS
/// are (potentially problematic) pointers.
///
/// \returns True when the operand is valid to use (even if as an extension).
static bool checkArithmeticBinOpPointerOperands(Sema &S, SourceLocation Loc,
Expr *LHSExpr, Expr *RHSExpr) {
bool isLHSPointer = LHSExpr->getType()->isAnyPointerType();
bool isRHSPointer = RHSExpr->getType()->isAnyPointerType();
if (!isLHSPointer && !isRHSPointer) return true;
QualType LHSPointeeTy, RHSPointeeTy;
if (isLHSPointer) LHSPointeeTy = LHSExpr->getType()->getPointeeType();
if (isRHSPointer) RHSPointeeTy = RHSExpr->getType()->getPointeeType();
// if both are pointers check if operation is valid wrt address spaces
if (S.getLangOpts().OpenCL && isLHSPointer && isRHSPointer) {
const PointerType *lhsPtr = LHSExpr->getType()->getAs<PointerType>();
const PointerType *rhsPtr = RHSExpr->getType()->getAs<PointerType>();
if (!lhsPtr->isAddressSpaceOverlapping(*rhsPtr)) {
S.Diag(Loc,
diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
<< LHSExpr->getType() << RHSExpr->getType() << 1 /*arithmetic op*/
<< LHSExpr->getSourceRange() << RHSExpr->getSourceRange();
return false;
}
}
// Check for arithmetic on pointers to incomplete types.
bool isLHSVoidPtr = isLHSPointer && LHSPointeeTy->isVoidType();
bool isRHSVoidPtr = isRHSPointer && RHSPointeeTy->isVoidType();
if (isLHSVoidPtr || isRHSVoidPtr) {
if (!isRHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, LHSExpr);
else if (!isLHSVoidPtr) diagnoseArithmeticOnVoidPointer(S, Loc, RHSExpr);
else diagnoseArithmeticOnTwoVoidPointers(S, Loc, LHSExpr, RHSExpr);
return !S.getLangOpts().CPlusPlus;
}
bool isLHSFuncPtr = isLHSPointer && LHSPointeeTy->isFunctionType();
bool isRHSFuncPtr = isRHSPointer && RHSPointeeTy->isFunctionType();
if (isLHSFuncPtr || isRHSFuncPtr) {
if (!isRHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc, LHSExpr);
else if (!isLHSFuncPtr) diagnoseArithmeticOnFunctionPointer(S, Loc,
RHSExpr);
else diagnoseArithmeticOnTwoFunctionPointers(S, Loc, LHSExpr, RHSExpr);
return !S.getLangOpts().CPlusPlus;
}
if (isLHSPointer && checkArithmeticIncompletePointerType(S, Loc, LHSExpr))
return false;
if (isRHSPointer && checkArithmeticIncompletePointerType(S, Loc, RHSExpr))
return false;
return true;
}
/// diagnoseStringPlusInt - Emit a warning when adding an integer to a string
/// literal.
static void diagnoseStringPlusInt(Sema &Self, SourceLocation OpLoc,
Expr *LHSExpr, Expr *RHSExpr) {
StringLiteral* StrExpr = dyn_cast<StringLiteral>(LHSExpr->IgnoreImpCasts());
Expr* IndexExpr = RHSExpr;
if (!StrExpr) {
StrExpr = dyn_cast<StringLiteral>(RHSExpr->IgnoreImpCasts());
IndexExpr = LHSExpr;
}
bool IsStringPlusInt = StrExpr &&
IndexExpr->getType()->isIntegralOrUnscopedEnumerationType();
if (!IsStringPlusInt || IndexExpr->isValueDependent())
return;
llvm::APSInt index;
if (IndexExpr->EvaluateAsInt(index, Self.getASTContext())) {
unsigned StrLenWithNull = StrExpr->getLength() + 1;
if (index.isNonNegative() &&
index <= llvm::APSInt(llvm::APInt(index.getBitWidth(), StrLenWithNull),
index.isUnsigned()))
return;
}
SourceRange DiagRange(LHSExpr->getLocStart(), RHSExpr->getLocEnd());
Self.Diag(OpLoc, diag::warn_string_plus_int)
<< DiagRange << IndexExpr->IgnoreImpCasts()->getType();
// Only print a fixit for "str" + int, not for int + "str".
if (IndexExpr == RHSExpr) {
SourceLocation EndLoc = Self.getLocForEndOfToken(RHSExpr->getLocEnd());
Self.Diag(OpLoc, diag::note_string_plus_scalar_silence)
<< FixItHint::CreateInsertion(LHSExpr->getLocStart(), "&")
<< FixItHint::CreateReplacement(SourceRange(OpLoc), "[")
<< FixItHint::CreateInsertion(EndLoc, "]");
} else
Self.Diag(OpLoc, diag::note_string_plus_scalar_silence);
}
/// Emit a warning when adding a char literal to a string.
static void diagnoseStringPlusChar(Sema &Self, SourceLocation OpLoc,
Expr *LHSExpr, Expr *RHSExpr) {
const Expr *StringRefExpr = LHSExpr;
const CharacterLiteral *CharExpr =
dyn_cast<CharacterLiteral>(RHSExpr->IgnoreImpCasts());
if (!CharExpr) {
CharExpr = dyn_cast<CharacterLiteral>(LHSExpr->IgnoreImpCasts());
StringRefExpr = RHSExpr;
}
if (!CharExpr || !StringRefExpr)
return;
const QualType StringType = StringRefExpr->getType();
// Return if not a PointerType.
if (!StringType->isAnyPointerType())
return;
// Return if not a CharacterType.
if (!StringType->getPointeeType()->isAnyCharacterType())
return;
ASTContext &Ctx = Self.getASTContext();
SourceRange DiagRange(LHSExpr->getLocStart(), RHSExpr->getLocEnd());
const QualType CharType = CharExpr->getType();
if (!CharType->isAnyCharacterType() &&
CharType->isIntegerType() &&
llvm::isUIntN(Ctx.getCharWidth(), CharExpr->getValue())) {
Self.Diag(OpLoc, diag::warn_string_plus_char)
<< DiagRange << Ctx.CharTy;
} else {
Self.Diag(OpLoc, diag::warn_string_plus_char)
<< DiagRange << CharExpr->getType();
}
// Only print a fixit for str + char, not for char + str.
if (isa<CharacterLiteral>(RHSExpr->IgnoreImpCasts())) {
SourceLocation EndLoc = Self.getLocForEndOfToken(RHSExpr->getLocEnd());
Self.Diag(OpLoc, diag::note_string_plus_scalar_silence)
<< FixItHint::CreateInsertion(LHSExpr->getLocStart(), "&")
<< FixItHint::CreateReplacement(SourceRange(OpLoc), "[")
<< FixItHint::CreateInsertion(EndLoc, "]");
} else {
Self.Diag(OpLoc, diag::note_string_plus_scalar_silence);
}
}
/// Emit error when two pointers are incompatible.
static void diagnosePointerIncompatibility(Sema &S, SourceLocation Loc,
Expr *LHSExpr, Expr *RHSExpr) {
assert(LHSExpr->getType()->isAnyPointerType());
assert(RHSExpr->getType()->isAnyPointerType());
S.Diag(Loc, diag::err_typecheck_sub_ptr_compatible)
<< LHSExpr->getType() << RHSExpr->getType() << LHSExpr->getSourceRange()
<< RHSExpr->getSourceRange();
}
// C99 6.5.6
QualType Sema::CheckAdditionOperands(ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc, BinaryOperatorKind Opc,
QualType* CompLHSTy) {
checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
if (LHS.get()->getType()->isVectorType() ||
RHS.get()->getType()->isVectorType()) {
QualType compType = CheckVectorOperands(
LHS, RHS, Loc, CompLHSTy,
/*AllowBothBool*/getLangOpts().AltiVec,
/*AllowBoolConversions*/getLangOpts().ZVector);
if (CompLHSTy) *CompLHSTy = compType;
return compType;
}
QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy);
if (LHS.isInvalid() || RHS.isInvalid())
return QualType();
// Diagnose "string literal" '+' int and string '+' "char literal".
if (Opc == BO_Add) {
diagnoseStringPlusInt(*this, Loc, LHS.get(), RHS.get());
diagnoseStringPlusChar(*this, Loc, LHS.get(), RHS.get());
}
// handle the common case first (both operands are arithmetic).
if (!compType.isNull() && compType->isArithmeticType()) {
if (CompLHSTy) *CompLHSTy = compType;
return compType;
}
// Type-checking. Ultimately the pointer's going to be in PExp;
// note that we bias towards the LHS being the pointer.
Expr *PExp = LHS.get(), *IExp = RHS.get();
bool isObjCPointer;
if (PExp->getType()->isPointerType()) {
isObjCPointer = false;
} else if (PExp->getType()->isObjCObjectPointerType()) {
isObjCPointer = true;
} else {
std::swap(PExp, IExp);
if (PExp->getType()->isPointerType()) {
isObjCPointer = false;
} else if (PExp->getType()->isObjCObjectPointerType()) {
isObjCPointer = true;
} else {
return InvalidOperands(Loc, LHS, RHS);
}
}
assert(PExp->getType()->isAnyPointerType());
if (!IExp->getType()->isIntegerType())
return InvalidOperands(Loc, LHS, RHS);
// Adding to a null pointer results in undefined behavior.
if (PExp->IgnoreParenCasts()->isNullPointerConstant(
Context, Expr::NPC_ValueDependentIsNotNull)) {
// In C++ adding zero to a null pointer is defined.
llvm::APSInt KnownVal;
if (!getLangOpts().CPlusPlus ||
(!IExp->isValueDependent() &&
(!IExp->EvaluateAsInt(KnownVal, Context) || KnownVal != 0))) {
// Check the conditions to see if this is the 'p = nullptr + n' idiom.
bool IsGNUIdiom = BinaryOperator::isNullPointerArithmeticExtension(
Context, BO_Add, PExp, IExp);
diagnoseArithmeticOnNullPointer(*this, Loc, PExp, IsGNUIdiom);
}
}
if (!checkArithmeticOpPointerOperand(*this, Loc, PExp))
return QualType();
if (isObjCPointer && checkArithmeticOnObjCPointer(*this, Loc, PExp))
return QualType();
// Check array bounds for pointer arithemtic
CheckArrayAccess(PExp, IExp);
if (CompLHSTy) {
QualType LHSTy = Context.isPromotableBitField(LHS.get());
if (LHSTy.isNull()) {
LHSTy = LHS.get()->getType();
if (LHSTy->isPromotableIntegerType())
LHSTy = Context.getPromotedIntegerType(LHSTy);
}
*CompLHSTy = LHSTy;
}
return PExp->getType();
}
// C99 6.5.6
QualType Sema::CheckSubtractionOperands(ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc,
QualType* CompLHSTy) {
checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
if (LHS.get()->getType()->isVectorType() ||
RHS.get()->getType()->isVectorType()) {
QualType compType = CheckVectorOperands(
LHS, RHS, Loc, CompLHSTy,
/*AllowBothBool*/getLangOpts().AltiVec,
/*AllowBoolConversions*/getLangOpts().ZVector);
if (CompLHSTy) *CompLHSTy = compType;
return compType;
}
QualType compType = UsualArithmeticConversions(LHS, RHS, CompLHSTy);
if (LHS.isInvalid() || RHS.isInvalid())
return QualType();
// Enforce type constraints: C99 6.5.6p3.
// Handle the common case first (both operands are arithmetic).
if (!compType.isNull() && compType->isArithmeticType()) {
if (CompLHSTy) *CompLHSTy = compType;
return compType;
}
// Either ptr - int or ptr - ptr.
if (LHS.get()->getType()->isAnyPointerType()) {
QualType lpointee = LHS.get()->getType()->getPointeeType();
// Diagnose bad cases where we step over interface counts.
if (LHS.get()->getType()->isObjCObjectPointerType() &&
checkArithmeticOnObjCPointer(*this, Loc, LHS.get()))
return QualType();
// The result type of a pointer-int computation is the pointer type.
if (RHS.get()->getType()->isIntegerType()) {
// Subtracting from a null pointer should produce a warning.
// The last argument to the diagnose call says this doesn't match the
// GNU int-to-pointer idiom.
if (LHS.get()->IgnoreParenCasts()->isNullPointerConstant(Context,
Expr::NPC_ValueDependentIsNotNull)) {
// In C++ adding zero to a null pointer is defined.
llvm::APSInt KnownVal;
if (!getLangOpts().CPlusPlus ||
(!RHS.get()->isValueDependent() &&
(!RHS.get()->EvaluateAsInt(KnownVal, Context) || KnownVal != 0))) {
diagnoseArithmeticOnNullPointer(*this, Loc, LHS.get(), false);
}
}
if (!checkArithmeticOpPointerOperand(*this, Loc, LHS.get()))
return QualType();
// Check array bounds for pointer arithemtic
CheckArrayAccess(LHS.get(), RHS.get(), /*ArraySubscriptExpr*/nullptr,
/*AllowOnePastEnd*/true, /*IndexNegated*/true);
if (CompLHSTy) *CompLHSTy = LHS.get()->getType();
return LHS.get()->getType();
}
// Handle pointer-pointer subtractions.
if (const PointerType *RHSPTy
= RHS.get()->getType()->getAs<PointerType>()) {
QualType rpointee = RHSPTy->getPointeeType();
if (getLangOpts().CPlusPlus) {
// Pointee types must be the same: C++ [expr.add]
if (!Context.hasSameUnqualifiedType(lpointee, rpointee)) {
diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get());
}
} else {
// Pointee types must be compatible C99 6.5.6p3
if (!Context.typesAreCompatible(
Context.getCanonicalType(lpointee).getUnqualifiedType(),
Context.getCanonicalType(rpointee).getUnqualifiedType())) {
diagnosePointerIncompatibility(*this, Loc, LHS.get(), RHS.get());
return QualType();
}
}
if (!checkArithmeticBinOpPointerOperands(*this, Loc,
LHS.get(), RHS.get()))
return QualType();
// FIXME: Add warnings for nullptr - ptr.
// The pointee type may have zero size. As an extension, a structure or
// union may have zero size or an array may have zero length. In this
// case subtraction does not make sense.
if (!rpointee->isVoidType() && !rpointee->isFunctionType()) {
CharUnits ElementSize = Context.getTypeSizeInChars(rpointee);
if (ElementSize.isZero()) {
Diag(Loc,diag::warn_sub_ptr_zero_size_types)
<< rpointee.getUnqualifiedType()
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
}
}
if (CompLHSTy) *CompLHSTy = LHS.get()->getType();
return Context.getPointerDiffType();
}
}
return InvalidOperands(Loc, LHS, RHS);
}
static bool isScopedEnumerationType(QualType T) {
if (const EnumType *ET = T->getAs<EnumType>())
return ET->getDecl()->isScoped();
return false;
}
static void DiagnoseBadShiftValues(Sema& S, ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc, BinaryOperatorKind Opc,
QualType LHSType) {
// OpenCL 6.3j: shift values are effectively % word size of LHS (more defined),
// so skip remaining warnings as we don't want to modify values within Sema.
if (S.getLangOpts().OpenCL)
return;
llvm::APSInt Right;
// Check right/shifter operand
if (RHS.get()->isValueDependent() ||
!RHS.get()->EvaluateAsInt(Right, S.Context))
return;
if (Right.isNegative()) {
S.DiagRuntimeBehavior(Loc, RHS.get(),
S.PDiag(diag::warn_shift_negative)
<< RHS.get()->getSourceRange());
return;
}
llvm::APInt LeftBits(Right.getBitWidth(),
S.Context.getTypeSize(LHS.get()->getType()));
if (Right.uge(LeftBits)) {
S.DiagRuntimeBehavior(Loc, RHS.get(),
S.PDiag(diag::warn_shift_gt_typewidth)
<< RHS.get()->getSourceRange());
return;
}
if (Opc != BO_Shl)
return;
// When left shifting an ICE which is signed, we can check for overflow which
// according to C++ has undefined behavior ([expr.shift] 5.8/2). Unsigned
// integers have defined behavior modulo one more than the maximum value
// representable in the result type, so never warn for those.
llvm::APSInt Left;
if (LHS.get()->isValueDependent() ||
LHSType->hasUnsignedIntegerRepresentation() ||
!LHS.get()->EvaluateAsInt(Left, S.Context))
return;
// If LHS does not have a signed type and non-negative value
// then, the behavior is undefined. Warn about it.
if (Left.isNegative() && !S.getLangOpts().isSignedOverflowDefined()) {
S.DiagRuntimeBehavior(Loc, LHS.get(),
S.PDiag(diag::warn_shift_lhs_negative)
<< LHS.get()->getSourceRange());
return;
}
llvm::APInt ResultBits =
static_cast<llvm::APInt&>(Right) + Left.getMinSignedBits();
if (LeftBits.uge(ResultBits))
return;
llvm::APSInt Result = Left.extend(ResultBits.getLimitedValue());
Result = Result.shl(Right);
// Print the bit representation of the signed integer as an unsigned
// hexadecimal number.
SmallString<40> HexResult;
Result.toString(HexResult, 16, /*Signed =*/false, /*Literal =*/true);
// If we are only missing a sign bit, this is less likely to result in actual
// bugs -- if the result is cast back to an unsigned type, it will have the
// expected value. Thus we place this behind a different warning that can be
// turned off separately if needed.
if (LeftBits == ResultBits - 1) {
S.Diag(Loc, diag::warn_shift_result_sets_sign_bit)
<< HexResult << LHSType
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
return;
}
S.Diag(Loc, diag::warn_shift_result_gt_typewidth)
<< HexResult.str() << Result.getMinSignedBits() << LHSType
<< Left.getBitWidth() << LHS.get()->getSourceRange()
<< RHS.get()->getSourceRange();
}
/// Return the resulting type when a vector is shifted
/// by a scalar or vector shift amount.
static QualType checkVectorShift(Sema &S, ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc, bool IsCompAssign) {
// OpenCL v1.1 s6.3.j says RHS can be a vector only if LHS is a vector.
if ((S.LangOpts.OpenCL || S.LangOpts.ZVector) &&
!LHS.get()->getType()->isVectorType()) {
S.Diag(Loc, diag::err_shift_rhs_only_vector)
<< RHS.get()->getType() << LHS.get()->getType()
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
return QualType();
}
if (!IsCompAssign) {
LHS = S.UsualUnaryConversions(LHS.get());
if (LHS.isInvalid()) return QualType();
}
RHS = S.UsualUnaryConversions(RHS.get());
if (RHS.isInvalid()) return QualType();
QualType LHSType = LHS.get()->getType();
// Note that LHS might be a scalar because the routine calls not only in
// OpenCL case.
const VectorType *LHSVecTy = LHSType->getAs<VectorType>();
QualType LHSEleType = LHSVecTy ? LHSVecTy->getElementType() : LHSType;
// Note that RHS might not be a vector.
QualType RHSType = RHS.get()->getType();
const VectorType *RHSVecTy = RHSType->getAs<VectorType>();
QualType RHSEleType = RHSVecTy ? RHSVecTy->getElementType() : RHSType;
// The operands need to be integers.
if (!LHSEleType->isIntegerType()) {
S.Diag(Loc, diag::err_typecheck_expect_int)
<< LHS.get()->getType() << LHS.get()->getSourceRange();
return QualType();
}
if (!RHSEleType->isIntegerType()) {
S.Diag(Loc, diag::err_typecheck_expect_int)
<< RHS.get()->getType() << RHS.get()->getSourceRange();
return QualType();
}
if (!LHSVecTy) {
assert(RHSVecTy);
if (IsCompAssign)
return RHSType;
if (LHSEleType != RHSEleType) {
LHS = S.ImpCastExprToType(LHS.get(),RHSEleType, CK_IntegralCast);
LHSEleType = RHSEleType;
}
QualType VecTy =
S.Context.getExtVectorType(LHSEleType, RHSVecTy->getNumElements());
LHS = S.ImpCastExprToType(LHS.get(), VecTy, CK_VectorSplat);
LHSType = VecTy;
} else if (RHSVecTy) {
// OpenCL v1.1 s6.3.j says that for vector types, the operators
// are applied component-wise. So if RHS is a vector, then ensure
// that the number of elements is the same as LHS...
if (RHSVecTy->getNumElements() != LHSVecTy->getNumElements()) {
S.Diag(Loc, diag::err_typecheck_vector_lengths_not_equal)
<< LHS.get()->getType() << RHS.get()->getType()
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
return QualType();
}
if (!S.LangOpts.OpenCL && !S.LangOpts.ZVector) {
const BuiltinType *LHSBT = LHSEleType->getAs<clang::BuiltinType>();
const BuiltinType *RHSBT = RHSEleType->getAs<clang::BuiltinType>();
if (LHSBT != RHSBT &&
S.Context.getTypeSize(LHSBT) != S.Context.getTypeSize(RHSBT)) {
S.Diag(Loc, diag::warn_typecheck_vector_element_sizes_not_equal)
<< LHS.get()->getType() << RHS.get()->getType()
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
}
}
} else {
// ...else expand RHS to match the number of elements in LHS.
QualType VecTy =
S.Context.getExtVectorType(RHSEleType, LHSVecTy->getNumElements());
RHS = S.ImpCastExprToType(RHS.get(), VecTy, CK_VectorSplat);
}
return LHSType;
}
// C99 6.5.7
QualType Sema::CheckShiftOperands(ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc, BinaryOperatorKind Opc,
bool IsCompAssign) {
checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
// Vector shifts promote their scalar inputs to vector type.
if (LHS.get()->getType()->isVectorType() ||
RHS.get()->getType()->isVectorType()) {
if (LangOpts.ZVector) {
// The shift operators for the z vector extensions work basically
// like general shifts, except that neither the LHS nor the RHS is
// allowed to be a "vector bool".
if (auto LHSVecType = LHS.get()->getType()->getAs<VectorType>())
if (LHSVecType->getVectorKind() == VectorType::AltiVecBool)
return InvalidOperands(Loc, LHS, RHS);
if (auto RHSVecType = RHS.get()->getType()->getAs<VectorType>())
if (RHSVecType->getVectorKind() == VectorType::AltiVecBool)
return InvalidOperands(Loc, LHS, RHS);
}
return checkVectorShift(*this, LHS, RHS, Loc, IsCompAssign);
}
// Shifts don't perform usual arithmetic conversions, they just do integer
// promotions on each operand. C99 6.5.7p3
// For the LHS, do usual unary conversions, but then reset them away
// if this is a compound assignment.
ExprResult OldLHS = LHS;
LHS = UsualUnaryConversions(LHS.get());
if (LHS.isInvalid())
return QualType();
QualType LHSType = LHS.get()->getType();
if (IsCompAssign) LHS = OldLHS;
// The RHS is simpler.
RHS = UsualUnaryConversions(RHS.get());
if (RHS.isInvalid())
return QualType();
QualType RHSType = RHS.get()->getType();
// C99 6.5.7p2: Each of the operands shall have integer type.
if (!LHSType->hasIntegerRepresentation() ||
!RHSType->hasIntegerRepresentation())
return InvalidOperands(Loc, LHS, RHS);
// C++0x: Don't allow scoped enums. FIXME: Use something better than
// hasIntegerRepresentation() above instead of this.
if (isScopedEnumerationType(LHSType) ||
isScopedEnumerationType(RHSType)) {
return InvalidOperands(Loc, LHS, RHS);
}
// Sanity-check shift operands
DiagnoseBadShiftValues(*this, LHS, RHS, Loc, Opc, LHSType);
// "The type of the result is that of the promoted left operand."
return LHSType;
}
/// If two different enums are compared, raise a warning.
static void checkEnumComparison(Sema &S, SourceLocation Loc, Expr *LHS,
Expr *RHS) {
QualType LHSStrippedType = LHS->IgnoreParenImpCasts()->getType();
QualType RHSStrippedType = RHS->IgnoreParenImpCasts()->getType();
const EnumType *LHSEnumType = LHSStrippedType->getAs<EnumType>();
if (!LHSEnumType)
return;
const EnumType *RHSEnumType = RHSStrippedType->getAs<EnumType>();
if (!RHSEnumType)
return;
// Ignore anonymous enums.
if (!LHSEnumType->getDecl()->getIdentifier() &&
!LHSEnumType->getDecl()->getTypedefNameForAnonDecl())
return;
if (!RHSEnumType->getDecl()->getIdentifier() &&
!RHSEnumType->getDecl()->getTypedefNameForAnonDecl())
return;
if (S.Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType))
return;
S.Diag(Loc, diag::warn_comparison_of_mixed_enum_types)
<< LHSStrippedType << RHSStrippedType
<< LHS->getSourceRange() << RHS->getSourceRange();
}
/// Diagnose bad pointer comparisons.
static void diagnoseDistinctPointerComparison(Sema &S, SourceLocation Loc,
ExprResult &LHS, ExprResult &RHS,
bool IsError) {
S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_distinct_pointers
: diag::ext_typecheck_comparison_of_distinct_pointers)
<< LHS.get()->getType() << RHS.get()->getType()
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
}
/// Returns false if the pointers are converted to a composite type,
/// true otherwise.
static bool convertPointersToCompositeType(Sema &S, SourceLocation Loc,
ExprResult &LHS, ExprResult &RHS) {
// C++ [expr.rel]p2:
// [...] Pointer conversions (4.10) and qualification
// conversions (4.4) are performed on pointer operands (or on
// a pointer operand and a null pointer constant) to bring
// them to their composite pointer type. [...]
//
// C++ [expr.eq]p1 uses the same notion for (in)equality
// comparisons of pointers.
QualType LHSType = LHS.get()->getType();
QualType RHSType = RHS.get()->getType();
assert(LHSType->isPointerType() || RHSType->isPointerType() ||
LHSType->isMemberPointerType() || RHSType->isMemberPointerType());
QualType T = S.FindCompositePointerType(Loc, LHS, RHS);
if (T.isNull()) {
if ((LHSType->isPointerType() || LHSType->isMemberPointerType()) &&
(RHSType->isPointerType() || RHSType->isMemberPointerType()))
diagnoseDistinctPointerComparison(S, Loc, LHS, RHS, /*isError*/true);
else
S.InvalidOperands(Loc, LHS, RHS);
return true;
}
LHS = S.ImpCastExprToType(LHS.get(), T, CK_BitCast);
RHS = S.ImpCastExprToType(RHS.get(), T, CK_BitCast);
return false;
}
static void diagnoseFunctionPointerToVoidComparison(Sema &S, SourceLocation Loc,
ExprResult &LHS,
ExprResult &RHS,
bool IsError) {
S.Diag(Loc, IsError ? diag::err_typecheck_comparison_of_fptr_to_void
: diag::ext_typecheck_comparison_of_fptr_to_void)
<< LHS.get()->getType() << RHS.get()->getType()
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
}
static bool isObjCObjectLiteral(ExprResult &E) {
switch (E.get()->IgnoreParenImpCasts()->getStmtClass()) {
case Stmt::ObjCArrayLiteralClass:
case Stmt::ObjCDictionaryLiteralClass:
case Stmt::ObjCStringLiteralClass:
case Stmt::ObjCBoxedExprClass:
return true;
default:
// Note that ObjCBoolLiteral is NOT an object literal!
return false;
}
}
static bool hasIsEqualMethod(Sema &S, const Expr *LHS, const Expr *RHS) {
const ObjCObjectPointerType *Type =
LHS->getType()->getAs<ObjCObjectPointerType>();
// If this is not actually an Objective-C object, bail out.
if (!Type)
return false;
// Get the LHS object's interface type.
QualType InterfaceType = Type->getPointeeType();
// If the RHS isn't an Objective-C object, bail out.
if (!RHS->getType()->isObjCObjectPointerType())
return false;
// Try to find the -isEqual: method.
Selector IsEqualSel = S.NSAPIObj->getIsEqualSelector();
ObjCMethodDecl *Method = S.LookupMethodInObjectType(IsEqualSel,
InterfaceType,
/*instance=*/true);
if (!Method) {
if (Type->isObjCIdType()) {
// For 'id', just check the global pool.
Method = S.LookupInstanceMethodInGlobalPool(IsEqualSel, SourceRange(),
/*receiverId=*/true);
} else {
// Check protocols.
Method = S.LookupMethodInQualifiedType(IsEqualSel, Type,
/*instance=*/true);
}
}
if (!Method)
return false;
QualType T = Method->parameters()[0]->getType();
if (!T->isObjCObjectPointerType())
return false;
QualType R = Method->getReturnType();
if (!R->isScalarType())
return false;
return true;
}
Sema::ObjCLiteralKind Sema::CheckLiteralKind(Expr *FromE) {
FromE = FromE->IgnoreParenImpCasts();
switch (FromE->getStmtClass()) {
default:
break;
case Stmt::ObjCStringLiteralClass:
// "string literal"
return LK_String;
case Stmt::ObjCArrayLiteralClass:
// "array literal"
return LK_Array;
case Stmt::ObjCDictionaryLiteralClass:
// "dictionary literal"
return LK_Dictionary;
case Stmt::BlockExprClass:
return LK_Block;
case Stmt::ObjCBoxedExprClass: {
Expr *Inner = cast<ObjCBoxedExpr>(FromE)->getSubExpr()->IgnoreParens();
switch (Inner->getStmtClass()) {
case Stmt::IntegerLiteralClass:
case Stmt::FloatingLiteralClass:
case Stmt::CharacterLiteralClass:
case Stmt::ObjCBoolLiteralExprClass:
case Stmt::CXXBoolLiteralExprClass:
// "numeric literal"
return LK_Numeric;
case Stmt::ImplicitCastExprClass: {
CastKind CK = cast<CastExpr>(Inner)->getCastKind();
// Boolean literals can be represented by implicit casts.
if (CK == CK_IntegralToBoolean || CK == CK_IntegralCast)
return LK_Numeric;
break;
}
default:
break;
}
return LK_Boxed;
}
}
return LK_None;
}
static void diagnoseObjCLiteralComparison(Sema &S, SourceLocation Loc,
ExprResult &LHS, ExprResult &RHS,
BinaryOperator::Opcode Opc){
Expr *Literal;
Expr *Other;
if (isObjCObjectLiteral(LHS)) {
Literal = LHS.get();
Other = RHS.get();
} else {
Literal = RHS.get();
Other = LHS.get();
}
// Don't warn on comparisons against nil.
Other = Other->IgnoreParenCasts();
if (Other->isNullPointerConstant(S.getASTContext(),
Expr::NPC_ValueDependentIsNotNull))
return;
// This should be kept in sync with warn_objc_literal_comparison.
// LK_String should always be after the other literals, since it has its own
// warning flag.
Sema::ObjCLiteralKind LiteralKind = S.CheckLiteralKind(Literal);
assert(LiteralKind != Sema::LK_Block);
if (LiteralKind == Sema::LK_None) {
llvm_unreachable("Unknown Objective-C object literal kind");
}
if (LiteralKind == Sema::LK_String)
S.Diag(Loc, diag::warn_objc_string_literal_comparison)
<< Literal->getSourceRange();
else
S.Diag(Loc, diag::warn_objc_literal_comparison)
<< LiteralKind << Literal->getSourceRange();
if (BinaryOperator::isEqualityOp(Opc) &&
hasIsEqualMethod(S, LHS.get(), RHS.get())) {
SourceLocation Start = LHS.get()->getLocStart();
SourceLocation End = S.getLocForEndOfToken(RHS.get()->getLocEnd());
CharSourceRange OpRange =
CharSourceRange::getCharRange(Loc, S.getLocForEndOfToken(Loc));
S.Diag(Loc, diag::note_objc_literal_comparison_isequal)
<< FixItHint::CreateInsertion(Start, Opc == BO_EQ ? "[" : "![")
<< FixItHint::CreateReplacement(OpRange, " isEqual:")
<< FixItHint::CreateInsertion(End, "]");
}
}
/// Warns on !x < y, !x & y where !(x < y), !(x & y) was probably intended.
static void diagnoseLogicalNotOnLHSofCheck(Sema &S, ExprResult &LHS,
ExprResult &RHS, SourceLocation Loc,
BinaryOperatorKind Opc) {
// Check that left hand side is !something.
UnaryOperator *UO = dyn_cast<UnaryOperator>(LHS.get()->IgnoreImpCasts());
if (!UO || UO->getOpcode() != UO_LNot) return;
// Only check if the right hand side is non-bool arithmetic type.
if (RHS.get()->isKnownToHaveBooleanValue()) return;
// Make sure that the something in !something is not bool.
Expr *SubExpr = UO->getSubExpr()->IgnoreImpCasts();
if (SubExpr->isKnownToHaveBooleanValue()) return;
// Emit warning.
bool IsBitwiseOp = Opc == BO_And || Opc == BO_Or || Opc == BO_Xor;
S.Diag(UO->getOperatorLoc(), diag::warn_logical_not_on_lhs_of_check)
<< Loc << IsBitwiseOp;
// First note suggest !(x < y)
SourceLocation FirstOpen = SubExpr->getLocStart();
SourceLocation FirstClose = RHS.get()->getLocEnd();
FirstClose = S.getLocForEndOfToken(FirstClose);
if (FirstClose.isInvalid())
FirstOpen = SourceLocation();
S.Diag(UO->getOperatorLoc(), diag::note_logical_not_fix)
<< IsBitwiseOp
<< FixItHint::CreateInsertion(FirstOpen, "(")
<< FixItHint::CreateInsertion(FirstClose, ")");
// Second note suggests (!x) < y
SourceLocation SecondOpen = LHS.get()->getLocStart();
SourceLocation SecondClose = LHS.get()->getLocEnd();
SecondClose = S.getLocForEndOfToken(SecondClose);
if (SecondClose.isInvalid())
SecondOpen = SourceLocation();
S.Diag(UO->getOperatorLoc(), diag::note_logical_not_silence_with_parens)
<< FixItHint::CreateInsertion(SecondOpen, "(")
<< FixItHint::CreateInsertion(SecondClose, ")");
}
// Get the decl for a simple expression: a reference to a variable,
// an implicit C++ field reference, or an implicit ObjC ivar reference.
static ValueDecl *getCompareDecl(Expr *E) {
if (DeclRefExpr *DR = dyn_cast<DeclRefExpr>(E))
return DR->getDecl();
if (ObjCIvarRefExpr *Ivar = dyn_cast<ObjCIvarRefExpr>(E)) {
if (Ivar->isFreeIvar())
return Ivar->getDecl();
}
if (MemberExpr *Mem = dyn_cast<MemberExpr>(E)) {
if (Mem->isImplicitAccess())
return Mem->getMemberDecl();
}
return nullptr;
}
/// Diagnose some forms of syntactically-obvious tautological comparison.
static void diagnoseTautologicalComparison(Sema &S, SourceLocation Loc,
Expr *LHS, Expr *RHS,
BinaryOperatorKind Opc) {
Expr *LHSStripped = LHS->IgnoreParenImpCasts();
Expr *RHSStripped = RHS->IgnoreParenImpCasts();
QualType LHSType = LHS->getType();
QualType RHSType = RHS->getType();
if (LHSType->hasFloatingRepresentation() ||
(LHSType->isBlockPointerType() && !BinaryOperator::isEqualityOp(Opc)) ||
LHS->getLocStart().isMacroID() || RHS->getLocStart().isMacroID() ||
S.inTemplateInstantiation())
return;
// Comparisons between two array types are ill-formed for operator<=>, so
// we shouldn't emit any additional warnings about it.
if (Opc == BO_Cmp && LHSType->isArrayType() && RHSType->isArrayType())
return;
// For non-floating point types, check for self-comparisons of the form
// x == x, x != x, x < x, etc. These always evaluate to a constant, and
// often indicate logic errors in the program.
//
// NOTE: Don't warn about comparison expressions resulting from macro
// expansion. Also don't warn about comparisons which are only self
// comparisons within a template instantiation. The warnings should catch
// obvious cases in the definition of the template anyways. The idea is to
// warn when the typed comparison operator will always evaluate to the same
// result.
ValueDecl *DL = getCompareDecl(LHSStripped);
ValueDecl *DR = getCompareDecl(RHSStripped);
if (DL && DR && declaresSameEntity(DL, DR)) {
StringRef Result;
switch (Opc) {
case BO_EQ: case BO_LE: case BO_GE:
Result = "true";
break;
case BO_NE: case BO_LT: case BO_GT:
Result = "false";
break;
case BO_Cmp:
Result = "'std::strong_ordering::equal'";
break;
default:
break;
}
S.DiagRuntimeBehavior(Loc, nullptr,
S.PDiag(diag::warn_comparison_always)
<< 0 /*self-comparison*/ << !Result.empty()
<< Result);
} else if (DL && DR &&
DL->getType()->isArrayType() && DR->getType()->isArrayType() &&
!DL->isWeak() && !DR->isWeak()) {
// What is it always going to evaluate to?
StringRef Result;
switch(Opc) {
case BO_EQ: // e.g. array1 == array2
Result = "false";
break;
case BO_NE: // e.g. array1 != array2
Result = "true";
break;
default: // e.g. array1 <= array2
// The best we can say is 'a constant'
break;
}
S.DiagRuntimeBehavior(Loc, nullptr,
S.PDiag(diag::warn_comparison_always)
<< 1 /*array comparison*/
<< !Result.empty() << Result);
}
if (isa<CastExpr>(LHSStripped))
LHSStripped = LHSStripped->IgnoreParenCasts();
if (isa<CastExpr>(RHSStripped))
RHSStripped = RHSStripped->IgnoreParenCasts();
// Warn about comparisons against a string constant (unless the other
// operand is null); the user probably wants strcmp.
Expr *LiteralString = nullptr;
Expr *LiteralStringStripped = nullptr;
if ((isa<StringLiteral>(LHSStripped) || isa<ObjCEncodeExpr>(LHSStripped)) &&
!RHSStripped->isNullPointerConstant(S.Context,
Expr::NPC_ValueDependentIsNull)) {
LiteralString = LHS;
LiteralStringStripped = LHSStripped;
} else if ((isa<StringLiteral>(RHSStripped) ||
isa<ObjCEncodeExpr>(RHSStripped)) &&
!LHSStripped->isNullPointerConstant(S.Context,
Expr::NPC_ValueDependentIsNull)) {
LiteralString = RHS;
LiteralStringStripped = RHSStripped;
}
if (LiteralString) {
S.DiagRuntimeBehavior(Loc, nullptr,
S.PDiag(diag::warn_stringcompare)
<< isa<ObjCEncodeExpr>(LiteralStringStripped)
<< LiteralString->getSourceRange());
}
}
static ImplicitConversionKind castKindToImplicitConversionKind(CastKind CK) {
switch (CK) {
default: {
#ifndef NDEBUG
llvm::errs() << "unhandled cast kind: " << CastExpr::getCastKindName(CK)
<< "\n";
#endif
llvm_unreachable("unhandled cast kind");
}
case CK_UserDefinedConversion:
return ICK_Identity;
case CK_LValueToRValue:
return ICK_Lvalue_To_Rvalue;
case CK_ArrayToPointerDecay:
return ICK_Array_To_Pointer;
case CK_FunctionToPointerDecay:
return ICK_Function_To_Pointer;
case CK_IntegralCast:
return ICK_Integral_Conversion;
case CK_FloatingCast:
return ICK_Floating_Conversion;
case CK_IntegralToFloating:
case CK_FloatingToIntegral:
return ICK_Floating_Integral;
case CK_IntegralComplexCast:
case CK_FloatingComplexCast:
case CK_FloatingComplexToIntegralComplex:
case CK_IntegralComplexToFloatingComplex:
return ICK_Complex_Conversion;
case CK_FloatingComplexToReal:
case CK_FloatingRealToComplex:
case CK_IntegralComplexToReal:
case CK_IntegralRealToComplex:
return ICK_Complex_Real;
}
}
static bool checkThreeWayNarrowingConversion(Sema &S, QualType ToType, Expr *E,
QualType FromType,
SourceLocation Loc) {
// Check for a narrowing implicit conversion.
StandardConversionSequence SCS;
SCS.setAsIdentityConversion();
SCS.setToType(0, FromType);
SCS.setToType(1, ToType);
if (const auto *ICE = dyn_cast<ImplicitCastExpr>(E))
SCS.Second = castKindToImplicitConversionKind(ICE->getCastKind());
APValue PreNarrowingValue;
QualType PreNarrowingType;
switch (SCS.getNarrowingKind(S.Context, E, PreNarrowingValue,
PreNarrowingType,
/*IgnoreFloatToIntegralConversion*/ true)) {
case NK_Dependent_Narrowing:
// Implicit conversion to a narrower type, but the expression is
// value-dependent so we can't tell whether it's actually narrowing.
case NK_Not_Narrowing:
return false;
case NK_Constant_Narrowing:
// Implicit conversion to a narrower type, and the value is not a constant
// expression.
S.Diag(E->getLocStart(), diag::err_spaceship_argument_narrowing)
<< /*Constant*/ 1
<< PreNarrowingValue.getAsString(S.Context, PreNarrowingType) << ToType;
return true;
case NK_Variable_Narrowing:
// Implicit conversion to a narrower type, and the value is not a constant
// expression.
case NK_Type_Narrowing:
S.Diag(E->getLocStart(), diag::err_spaceship_argument_narrowing)
<< /*Constant*/ 0 << FromType << ToType;
// TODO: It's not a constant expression, but what if the user intended it
// to be? Can we produce notes to help them figure out why it isn't?
return true;
}
llvm_unreachable("unhandled case in switch");
}
static QualType checkArithmeticOrEnumeralThreeWayCompare(Sema &S,
ExprResult &LHS,
ExprResult &RHS,
SourceLocation Loc) {
using CCT = ComparisonCategoryType;
QualType LHSType = LHS.get()->getType();
QualType RHSType = RHS.get()->getType();
// Dig out the original argument type and expression before implicit casts
// were applied. These are the types/expressions we need to check the
// [expr.spaceship] requirements against.
ExprResult LHSStripped = LHS.get()->IgnoreParenImpCasts();
ExprResult RHSStripped = RHS.get()->IgnoreParenImpCasts();
QualType LHSStrippedType = LHSStripped.get()->getType();
QualType RHSStrippedType = RHSStripped.get()->getType();
// C++2a [expr.spaceship]p3: If one of the operands is of type bool and the
// other is not, the program is ill-formed.
if (LHSStrippedType->isBooleanType() != RHSStrippedType->isBooleanType()) {
S.InvalidOperands(Loc, LHSStripped, RHSStripped);
return QualType();
}
int NumEnumArgs = (int)LHSStrippedType->isEnumeralType() +
RHSStrippedType->isEnumeralType();
if (NumEnumArgs == 1) {
bool LHSIsEnum = LHSStrippedType->isEnumeralType();
QualType OtherTy = LHSIsEnum ? RHSStrippedType : LHSStrippedType;
if (OtherTy->hasFloatingRepresentation()) {
S.InvalidOperands(Loc, LHSStripped, RHSStripped);
return QualType();
}
}
if (NumEnumArgs == 2) {
// C++2a [expr.spaceship]p5: If both operands have the same enumeration
// type E, the operator yields the result of converting the operands
// to the underlying type of E and applying <=> to the converted operands.
if (!S.Context.hasSameUnqualifiedType(LHSStrippedType, RHSStrippedType)) {
S.InvalidOperands(Loc, LHS, RHS);
return QualType();
}
QualType IntType =
LHSStrippedType->getAs<EnumType>()->getDecl()->getIntegerType();
assert(IntType->isArithmeticType());
// We can't use `CK_IntegralCast` when the underlying type is 'bool', so we
// promote the boolean type, and all other promotable integer types, to
// avoid this.
if (IntType->isPromotableIntegerType())
IntType = S.Context.getPromotedIntegerType(IntType);
LHS = S.ImpCastExprToType(LHS.get(), IntType, CK_IntegralCast);
RHS = S.ImpCastExprToType(RHS.get(), IntType, CK_IntegralCast);
LHSType = RHSType = IntType;
}
// C++2a [expr.spaceship]p4: If both operands have arithmetic types, the
// usual arithmetic conversions are applied to the operands.
QualType Type = S.UsualArithmeticConversions(LHS, RHS);
if (LHS.isInvalid() || RHS.isInvalid())
return QualType();
if (Type.isNull())
return S.InvalidOperands(Loc, LHS, RHS);
assert(Type->isArithmeticType() || Type->isEnumeralType());
bool HasNarrowing = checkThreeWayNarrowingConversion(
S, Type, LHS.get(), LHSType, LHS.get()->getLocStart());
HasNarrowing |= checkThreeWayNarrowingConversion(
S, Type, RHS.get(), RHSType, RHS.get()->getLocStart());
if (HasNarrowing)
return QualType();
assert(!Type.isNull() && "composite type for <=> has not been set");
auto TypeKind = [&]() {
if (const ComplexType *CT = Type->getAs<ComplexType>()) {
if (CT->getElementType()->hasFloatingRepresentation())
return CCT::WeakEquality;
return CCT::StrongEquality;
}
if (Type->isIntegralOrEnumerationType())
return CCT::StrongOrdering;
if (Type->hasFloatingRepresentation())
return CCT::PartialOrdering;
llvm_unreachable("other types are unimplemented");
}();
return S.CheckComparisonCategoryType(TypeKind, Loc);
}
static QualType checkArithmeticOrEnumeralCompare(Sema &S, ExprResult &LHS,
ExprResult &RHS,
SourceLocation Loc,
BinaryOperatorKind Opc) {
if (Opc == BO_Cmp)
return checkArithmeticOrEnumeralThreeWayCompare(S, LHS, RHS, Loc);
// C99 6.5.8p3 / C99 6.5.9p4
QualType Type = S.UsualArithmeticConversions(LHS, RHS);
if (LHS.isInvalid() || RHS.isInvalid())
return QualType();
if (Type.isNull())
return S.InvalidOperands(Loc, LHS, RHS);
assert(Type->isArithmeticType() || Type->isEnumeralType());
checkEnumComparison(S, Loc, LHS.get(), RHS.get());
if (Type->isAnyComplexType() && BinaryOperator::isRelationalOp(Opc))
return S.InvalidOperands(Loc, LHS, RHS);
// Check for comparisons of floating point operands using != and ==.
if (Type->hasFloatingRepresentation() && BinaryOperator::isEqualityOp(Opc))
S.CheckFloatComparison(Loc, LHS.get(), RHS.get());
// The result of comparisons is 'bool' in C++, 'int' in C.
return S.Context.getLogicalOperationType();
}
// C99 6.5.8, C++ [expr.rel]
QualType Sema::CheckCompareOperands(ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc,
BinaryOperatorKind Opc) {
bool IsRelational = BinaryOperator::isRelationalOp(Opc);
bool IsThreeWay = Opc == BO_Cmp;
auto IsAnyPointerType = [](ExprResult E) {
QualType Ty = E.get()->getType();
return Ty->isPointerType() || Ty->isMemberPointerType();
};
// C++2a [expr.spaceship]p6: If at least one of the operands is of pointer
// type, array-to-pointer, ..., conversions are performed on both operands to
// bring them to their composite type.
// Otherwise, all comparisons expect an rvalue, so convert to rvalue before
// any type-related checks.
if (!IsThreeWay || IsAnyPointerType(LHS) || IsAnyPointerType(RHS)) {
LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
if (LHS.isInvalid())
return QualType();
RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
if (RHS.isInvalid())
return QualType();
} else {
LHS = DefaultLvalueConversion(LHS.get());
if (LHS.isInvalid())
return QualType();
RHS = DefaultLvalueConversion(RHS.get());
if (RHS.isInvalid())
return QualType();
}
checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/true);
// Handle vector comparisons separately.
if (LHS.get()->getType()->isVectorType() ||
RHS.get()->getType()->isVectorType())
return CheckVectorCompareOperands(LHS, RHS, Loc, Opc);
diagnoseLogicalNotOnLHSofCheck(*this, LHS, RHS, Loc, Opc);
diagnoseTautologicalComparison(*this, Loc, LHS.get(), RHS.get(), Opc);
QualType LHSType = LHS.get()->getType();
QualType RHSType = RHS.get()->getType();
if ((LHSType->isArithmeticType() || LHSType->isEnumeralType()) &&
(RHSType->isArithmeticType() || RHSType->isEnumeralType()))
return checkArithmeticOrEnumeralCompare(*this, LHS, RHS, Loc, Opc);
const Expr::NullPointerConstantKind LHSNullKind =
LHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull);
const Expr::NullPointerConstantKind RHSNullKind =
RHS.get()->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull);
bool LHSIsNull = LHSNullKind != Expr::NPCK_NotNull;
bool RHSIsNull = RHSNullKind != Expr::NPCK_NotNull;
auto computeResultTy = [&]() {
if (Opc != BO_Cmp)
return Context.getLogicalOperationType();
assert(getLangOpts().CPlusPlus);
assert(Context.hasSameType(LHS.get()->getType(), RHS.get()->getType()));
QualType CompositeTy = LHS.get()->getType();
assert(!CompositeTy->isReferenceType());
auto buildResultTy = [&](ComparisonCategoryType Kind) {
return CheckComparisonCategoryType(Kind, Loc);
};
// C++2a [expr.spaceship]p7: If the composite pointer type is a function
// pointer type, a pointer-to-member type, or std::nullptr_t, the
// result is of type std::strong_equality
if (CompositeTy->isFunctionPointerType() ||
CompositeTy->isMemberPointerType() || CompositeTy->isNullPtrType())
// FIXME: consider making the function pointer case produce
// strong_ordering not strong_equality, per P0946R0-Jax18 discussion
// and direction polls
return buildResultTy(ComparisonCategoryType::StrongEquality);
// C++2a [expr.spaceship]p8: If the composite pointer type is an object
// pointer type, p <=> q is of type std::strong_ordering.
if (CompositeTy->isPointerType()) {
// P0946R0: Comparisons between a null pointer constant and an object
// pointer result in std::strong_equality
if (LHSIsNull != RHSIsNull)
return buildResultTy(ComparisonCategoryType::StrongEquality);
return buildResultTy(ComparisonCategoryType::StrongOrdering);
}
// C++2a [expr.spaceship]p9: Otherwise, the program is ill-formed.
// TODO: Extend support for operator<=> to ObjC types.
return InvalidOperands(Loc, LHS, RHS);
};
if (!IsRelational && LHSIsNull != RHSIsNull) {
bool IsEquality = Opc == BO_EQ;
if (RHSIsNull)
DiagnoseAlwaysNonNullPointer(LHS.get(), RHSNullKind, IsEquality,
RHS.get()->getSourceRange());
else
DiagnoseAlwaysNonNullPointer(RHS.get(), LHSNullKind, IsEquality,
LHS.get()->getSourceRange());
}
if ((LHSType->isIntegerType() && !LHSIsNull) ||
(RHSType->isIntegerType() && !RHSIsNull)) {
// Skip normal pointer conversion checks in this case; we have better
// diagnostics for this below.
} else if (getLangOpts().CPlusPlus) {
// Equality comparison of a function pointer to a void pointer is invalid,
// but we allow it as an extension.
// FIXME: If we really want to allow this, should it be part of composite
// pointer type computation so it works in conditionals too?
if (!IsRelational &&
((LHSType->isFunctionPointerType() && RHSType->isVoidPointerType()) ||
(RHSType->isFunctionPointerType() && LHSType->isVoidPointerType()))) {
// This is a gcc extension compatibility comparison.
// In a SFINAE context, we treat this as a hard error to maintain
// conformance with the C++ standard.
diagnoseFunctionPointerToVoidComparison(
*this, Loc, LHS, RHS, /*isError*/ (bool)isSFINAEContext());
if (isSFINAEContext())
return QualType();
RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
return computeResultTy();
}
// C++ [expr.eq]p2:
// If at least one operand is a pointer [...] bring them to their
// composite pointer type.
// C++ [expr.spaceship]p6
// If at least one of the operands is of pointer type, [...] bring them
// to their composite pointer type.
// C++ [expr.rel]p2:
// If both operands are pointers, [...] bring them to their composite
// pointer type.
if ((int)LHSType->isPointerType() + (int)RHSType->isPointerType() >=
(IsRelational ? 2 : 1) &&
(!LangOpts.ObjCAutoRefCount || !(LHSType->isObjCObjectPointerType() ||
RHSType->isObjCObjectPointerType()))) {
if (convertPointersToCompositeType(*this, Loc, LHS, RHS))
return QualType();
return computeResultTy();
}
} else if (LHSType->isPointerType() &&
RHSType->isPointerType()) { // C99 6.5.8p2
// All of the following pointer-related warnings are GCC extensions, except
// when handling null pointer constants.
QualType LCanPointeeTy =
LHSType->castAs<PointerType>()->getPointeeType().getCanonicalType();
QualType RCanPointeeTy =
RHSType->castAs<PointerType>()->getPointeeType().getCanonicalType();
// C99 6.5.9p2 and C99 6.5.8p2
if (Context.typesAreCompatible(LCanPointeeTy.getUnqualifiedType(),
RCanPointeeTy.getUnqualifiedType())) {
// Valid unless a relational comparison of function pointers
if (IsRelational && LCanPointeeTy->isFunctionType()) {
Diag(Loc, diag::ext_typecheck_ordered_comparison_of_function_pointers)
<< LHSType << RHSType << LHS.get()->getSourceRange()
<< RHS.get()->getSourceRange();
}
} else if (!IsRelational &&
(LCanPointeeTy->isVoidType() || RCanPointeeTy->isVoidType())) {
// Valid unless comparison between non-null pointer and function pointer
if ((LCanPointeeTy->isFunctionType() || RCanPointeeTy->isFunctionType())
&& !LHSIsNull && !RHSIsNull)
diagnoseFunctionPointerToVoidComparison(*this, Loc, LHS, RHS,
/*isError*/false);
} else {
// Invalid
diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS, /*isError*/false);
}
if (LCanPointeeTy != RCanPointeeTy) {
// Treat NULL constant as a special case in OpenCL.
if (getLangOpts().OpenCL && !LHSIsNull && !RHSIsNull) {
const PointerType *LHSPtr = LHSType->getAs<PointerType>();
if (!LHSPtr->isAddressSpaceOverlapping(*RHSType->getAs<PointerType>())) {
Diag(Loc,
diag::err_typecheck_op_on_nonoverlapping_address_space_pointers)
<< LHSType << RHSType << 0 /* comparison */
<< LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
}
}
LangAS AddrSpaceL = LCanPointeeTy.getAddressSpace();
LangAS AddrSpaceR = RCanPointeeTy.getAddressSpace();
CastKind Kind = AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion
: CK_BitCast;
if (LHSIsNull && !RHSIsNull)
LHS = ImpCastExprToType(LHS.get(), RHSType, Kind);
else
RHS = ImpCastExprToType(RHS.get(), LHSType, Kind);
}
return computeResultTy();
}
if (getLangOpts().CPlusPlus) {
// C++ [expr.eq]p4:
// Two operands of type std::nullptr_t or one operand of type
// std::nullptr_t and the other a null pointer constant compare equal.
if (!IsRelational && LHSIsNull && RHSIsNull) {
if (LHSType->isNullPtrType()) {
RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
return computeResultTy();
}
if (RHSType->isNullPtrType()) {
LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
return computeResultTy();
}
}
// Comparison of Objective-C pointers and block pointers against nullptr_t.
// These aren't covered by the composite pointer type rules.
if (!IsRelational && RHSType->isNullPtrType() &&
(LHSType->isObjCObjectPointerType() || LHSType->isBlockPointerType())) {
RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
return computeResultTy();
}
if (!IsRelational && LHSType->isNullPtrType() &&
(RHSType->isObjCObjectPointerType() || RHSType->isBlockPointerType())) {
LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
return computeResultTy();
}
if (IsRelational &&
((LHSType->isNullPtrType() && RHSType->isPointerType()) ||
(RHSType->isNullPtrType() && LHSType->isPointerType()))) {
// HACK: Relational comparison of nullptr_t against a pointer type is
// invalid per DR583, but we allow it within std::less<> and friends,
// since otherwise common uses of it break.
// FIXME: Consider removing this hack once LWG fixes std::less<> and
// friends to have std::nullptr_t overload candidates.
DeclContext *DC = CurContext;
if (isa<FunctionDecl>(DC))
DC = DC->getParent();
if (auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(DC)) {
if (CTSD->isInStdNamespace() &&
llvm::StringSwitch<bool>(CTSD->getName())
.Cases("less", "less_equal", "greater", "greater_equal", true)
.Default(false)) {
if (RHSType->isNullPtrType())
RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
else
LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
return computeResultTy();
}
}
}
// C++ [expr.eq]p2:
// If at least one operand is a pointer to member, [...] bring them to
// their composite pointer type.
if (!IsRelational &&
(LHSType->isMemberPointerType() || RHSType->isMemberPointerType())) {
if (convertPointersToCompositeType(*this, Loc, LHS, RHS))
return QualType();
else
return computeResultTy();
}
}
// Handle block pointer types.
if (!IsRelational && LHSType->isBlockPointerType() &&
RHSType->isBlockPointerType()) {
QualType lpointee = LHSType->castAs<BlockPointerType>()->getPointeeType();
QualType rpointee = RHSType->castAs<BlockPointerType>()->getPointeeType();
if (!LHSIsNull && !RHSIsNull &&
!Context.typesAreCompatible(lpointee, rpointee)) {
Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks)
<< LHSType << RHSType << LHS.get()->getSourceRange()
<< RHS.get()->getSourceRange();
}
RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
return computeResultTy();
}
// Allow block pointers to be compared with null pointer constants.
if (!IsRelational
&& ((LHSType->isBlockPointerType() && RHSType->isPointerType())
|| (LHSType->isPointerType() && RHSType->isBlockPointerType()))) {
if (!LHSIsNull && !RHSIsNull) {
if (!((RHSType->isPointerType() && RHSType->castAs<PointerType>()
->getPointeeType()->isVoidType())
|| (LHSType->isPointerType() && LHSType->castAs<PointerType>()
->getPointeeType()->isVoidType())))
Diag(Loc, diag::err_typecheck_comparison_of_distinct_blocks)
<< LHSType << RHSType << LHS.get()->getSourceRange()
<< RHS.get()->getSourceRange();
}
if (LHSIsNull && !RHSIsNull)
LHS = ImpCastExprToType(LHS.get(), RHSType,
RHSType->isPointerType() ? CK_BitCast
: CK_AnyPointerToBlockPointerCast);
else
RHS = ImpCastExprToType(RHS.get(), LHSType,
LHSType->isPointerType() ? CK_BitCast
: CK_AnyPointerToBlockPointerCast);
return computeResultTy();
}
if (LHSType->isObjCObjectPointerType() ||
RHSType->isObjCObjectPointerType()) {
const PointerType *LPT = LHSType->getAs<PointerType>();
const PointerType *RPT = RHSType->getAs<PointerType>();
if (LPT || RPT) {
bool LPtrToVoid = LPT ? LPT->getPointeeType()->isVoidType() : false;
bool RPtrToVoid = RPT ? RPT->getPointeeType()->isVoidType() : false;
if (!LPtrToVoid && !RPtrToVoid &&
!Context.typesAreCompatible(LHSType, RHSType)) {
diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS,
/*isError*/false);
}
if (LHSIsNull && !RHSIsNull) {
Expr *E = LHS.get();
if (getLangOpts().ObjCAutoRefCount)
CheckObjCConversion(SourceRange(), RHSType, E,
CCK_ImplicitConversion);
LHS = ImpCastExprToType(E, RHSType,
RPT ? CK_BitCast :CK_CPointerToObjCPointerCast);
}
else {
Expr *E = RHS.get();
if (getLangOpts().ObjCAutoRefCount)
CheckObjCConversion(SourceRange(), LHSType, E, CCK_ImplicitConversion,
/*Diagnose=*/true,
/*DiagnoseCFAudited=*/false, Opc);
RHS = ImpCastExprToType(E, LHSType,
LPT ? CK_BitCast :CK_CPointerToObjCPointerCast);
}
return computeResultTy();
}
if (LHSType->isObjCObjectPointerType() &&
RHSType->isObjCObjectPointerType()) {
if (!Context.areComparableObjCPointerTypes(LHSType, RHSType))
diagnoseDistinctPointerComparison(*this, Loc, LHS, RHS,
/*isError*/false);
if (isObjCObjectLiteral(LHS) || isObjCObjectLiteral(RHS))
diagnoseObjCLiteralComparison(*this, Loc, LHS, RHS, Opc);
if (LHSIsNull && !RHSIsNull)
LHS = ImpCastExprToType(LHS.get(), RHSType, CK_BitCast);
else
RHS = ImpCastExprToType(RHS.get(), LHSType, CK_BitCast);
return computeResultTy();
}
if (!IsRelational && LHSType->isBlockPointerType() &&
RHSType->isBlockCompatibleObjCPointerType(Context)) {
LHS = ImpCastExprToType(LHS.get(), RHSType,
CK_BlockPointerToObjCPointerCast);
return computeResultTy();
} else if (!IsRelational &&
LHSType->isBlockCompatibleObjCPointerType(Context) &&
RHSType->isBlockPointerType()) {
RHS = ImpCastExprToType(RHS.get(), LHSType,
CK_BlockPointerToObjCPointerCast);
return computeResultTy();
}
}
if ((LHSType->isAnyPointerType() && RHSType->isIntegerType()) ||
(LHSType->isIntegerType() && RHSType->isAnyPointerType())) {
unsigned DiagID = 0;
bool isError = false;
if (LangOpts.DebuggerSupport) {
// Under a debugger, allow the comparison of pointers to integers,
// since users tend to want to compare addresses.
} else if ((LHSIsNull && LHSType->isIntegerType()) ||
(RHSIsNull && RHSType->isIntegerType())) {
if (IsRelational) {
isError = getLangOpts().CPlusPlus;
DiagID =
isError ? diag::err_typecheck_ordered_comparison_of_pointer_and_zero
: diag::ext_typecheck_ordered_comparison_of_pointer_and_zero;
}
} else if (getLangOpts().CPlusPlus) {
DiagID = diag::err_typecheck_comparison_of_pointer_integer;
isError = true;
} else if (IsRelational)
DiagID = diag::ext_typecheck_ordered_comparison_of_pointer_integer;
else
DiagID = diag::ext_typecheck_comparison_of_pointer_integer;
if (DiagID) {
Diag(Loc, DiagID)
<< LHSType << RHSType << LHS.get()->getSourceRange()
<< RHS.get()->getSourceRange();
if (isError)
return QualType();
}
if (LHSType->isIntegerType())
LHS = ImpCastExprToType(LHS.get(), RHSType,
LHSIsNull ? CK_NullToPointer : CK_IntegralToPointer);
else
RHS = ImpCastExprToType(RHS.get(), LHSType,
RHSIsNull ? CK_NullToPointer : CK_IntegralToPointer);
return computeResultTy();
}
// Handle block pointers.
if (!IsRelational && RHSIsNull
&& LHSType->isBlockPointerType() && RHSType->isIntegerType()) {
RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
return computeResultTy();
}
if (!IsRelational && LHSIsNull
&& LHSType->isIntegerType() && RHSType->isBlockPointerType()) {
LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
return computeResultTy();
}
if (getLangOpts().OpenCLVersion >= 200) {
if (LHSIsNull && RHSType->isQueueT()) {
LHS = ImpCastExprToType(LHS.get(), RHSType, CK_NullToPointer);
return computeResultTy();
}
if (LHSType->isQueueT() && RHSIsNull) {
RHS = ImpCastExprToType(RHS.get(), LHSType, CK_NullToPointer);
return computeResultTy();
}
}
return InvalidOperands(Loc, LHS, RHS);
}
// Return a signed ext_vector_type that is of identical size and number of
// elements. For floating point vectors, return an integer type of identical
// size and number of elements. In the non ext_vector_type case, search from
// the largest type to the smallest type to avoid cases where long long == long,
// where long gets picked over long long.
QualType Sema::GetSignedVectorType(QualType V) {
const VectorType *VTy = V->getAs<VectorType>();
unsigned TypeSize = Context.getTypeSize(VTy->getElementType());
if (isa<ExtVectorType>(VTy)) {
if (TypeSize == Context.getTypeSize(Context.CharTy))
return Context.getExtVectorType(Context.CharTy, VTy->getNumElements());
else if (TypeSize == Context.getTypeSize(Context.ShortTy))
return Context.getExtVectorType(Context.ShortTy, VTy->getNumElements());
else if (TypeSize == Context.getTypeSize(Context.IntTy))
return Context.getExtVectorType(Context.IntTy, VTy->getNumElements());
else if (TypeSize == Context.getTypeSize(Context.LongTy))
return Context.getExtVectorType(Context.LongTy, VTy->getNumElements());
assert(TypeSize == Context.getTypeSize(Context.LongLongTy) &&
"Unhandled vector element size in vector compare");
return Context.getExtVectorType(Context.LongLongTy, VTy->getNumElements());
}
if (TypeSize == Context.getTypeSize(Context.LongLongTy))
return Context.getVectorType(Context.LongLongTy, VTy->getNumElements(),
VectorType::GenericVector);
else if (TypeSize == Context.getTypeSize(Context.LongTy))
return Context.getVectorType(Context.LongTy, VTy->getNumElements(),
VectorType::GenericVector);
else if (TypeSize == Context.getTypeSize(Context.IntTy))
return Context.getVectorType(Context.IntTy, VTy->getNumElements(),
VectorType::GenericVector);
else if (TypeSize == Context.getTypeSize(Context.ShortTy))
return Context.getVectorType(Context.ShortTy, VTy->getNumElements(),
VectorType::GenericVector);
assert(TypeSize == Context.getTypeSize(Context.CharTy) &&
"Unhandled vector element size in vector compare");
return Context.getVectorType(Context.CharTy, VTy->getNumElements(),
VectorType::GenericVector);
}
/// CheckVectorCompareOperands - vector comparisons are a clang extension that
/// operates on extended vector types. Instead of producing an IntTy result,
/// like a scalar comparison, a vector comparison produces a vector of integer
/// types.
QualType Sema::CheckVectorCompareOperands(ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc,
BinaryOperatorKind Opc) {
// Check to make sure we're operating on vectors of the same type and width,
// Allowing one side to be a scalar of element type.
QualType vType = CheckVectorOperands(LHS, RHS, Loc, /*isCompAssign*/false,
/*AllowBothBool*/true,
/*AllowBoolConversions*/getLangOpts().ZVector);
if (vType.isNull())
return vType;
QualType LHSType = LHS.get()->getType();
// If AltiVec, the comparison results in a numeric type, i.e.
// bool for C++, int for C
if (getLangOpts().AltiVec &&
vType->getAs<VectorType>()->getVectorKind() == VectorType::AltiVecVector)
return Context.getLogicalOperationType();
// For non-floating point types, check for self-comparisons of the form
// x == x, x != x, x < x, etc. These always evaluate to a constant, and
// often indicate logic errors in the program.
diagnoseTautologicalComparison(*this, Loc, LHS.get(), RHS.get(), Opc);
// Check for comparisons of floating point operands using != and ==.
if (BinaryOperator::isEqualityOp(Opc) &&
LHSType->hasFloatingRepresentation()) {
assert(RHS.get()->getType()->hasFloatingRepresentation());
CheckFloatComparison(Loc, LHS.get(), RHS.get());
}
// Return a signed type for the vector.
return GetSignedVectorType(vType);
}
QualType Sema::CheckVectorLogicalOperands(ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc) {
// Ensure that either both operands are of the same vector type, or
// one operand is of a vector type and the other is of its element type.
QualType vType = CheckVectorOperands(LHS, RHS, Loc, false,
/*AllowBothBool*/true,
/*AllowBoolConversions*/false);
if (vType.isNull())
return InvalidOperands(Loc, LHS, RHS);
if (getLangOpts().OpenCL && getLangOpts().OpenCLVersion < 120 &&
vType->hasFloatingRepresentation())
return InvalidOperands(Loc, LHS, RHS);
// FIXME: The check for C++ here is for GCC compatibility. GCC rejects the
// usage of the logical operators && and || with vectors in C. This
// check could be notionally dropped.
if (!getLangOpts().CPlusPlus &&
!(isa<ExtVectorType>(vType->getAs<VectorType>())))
return InvalidLogicalVectorOperands(Loc, LHS, RHS);
return GetSignedVectorType(LHS.get()->getType());
}
inline QualType Sema::CheckBitwiseOperands(ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc,
BinaryOperatorKind Opc) {
checkArithmeticNull(*this, LHS, RHS, Loc, /*isCompare=*/false);
bool IsCompAssign =
Opc == BO_AndAssign || Opc == BO_OrAssign || Opc == BO_XorAssign;
if (LHS.get()->getType()->isVectorType() ||
RHS.get()->getType()->isVectorType()) {
if (LHS.get()->getType()->hasIntegerRepresentation() &&
RHS.get()->getType()->hasIntegerRepresentation())
return CheckVectorOperands(LHS, RHS, Loc, IsCompAssign,
/*AllowBothBool*/true,
/*AllowBoolConversions*/getLangOpts().ZVector);
return InvalidOperands(Loc, LHS, RHS);
}
if (Opc == BO_And)
diagnoseLogicalNotOnLHSofCheck(*this, LHS, RHS, Loc, Opc);
ExprResult LHSResult = LHS, RHSResult = RHS;
QualType compType = UsualArithmeticConversions(LHSResult, RHSResult,
IsCompAssign);
if (LHSResult.isInvalid() || RHSResult.isInvalid())
return QualType();
LHS = LHSResult.get();
RHS = RHSResult.get();
if (!compType.isNull() && compType->isIntegralOrUnscopedEnumerationType())
return compType;
return InvalidOperands(Loc, LHS, RHS);
}
// C99 6.5.[13,14]
inline QualType Sema::CheckLogicalOperands(ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc,
BinaryOperatorKind Opc) {
// Check vector operands differently.
if (LHS.get()->getType()->isVectorType() || RHS.get()->getType()->isVectorType())
return CheckVectorLogicalOperands(LHS, RHS, Loc);
// Diagnose cases where the user write a logical and/or but probably meant a
// bitwise one. We do this when the LHS is a non-bool integer and the RHS
// is a constant.
if (LHS.get()->getType()->isIntegerType() &&
!LHS.get()->getType()->isBooleanType() &&
RHS.get()->getType()->isIntegerType() && !RHS.get()->isValueDependent() &&
// Don't warn in macros or template instantiations.
!Loc.isMacroID() && !inTemplateInstantiation()) {
// If the RHS can be constant folded, and if it constant folds to something
// that isn't 0 or 1 (which indicate a potential logical operation that
// happened to fold to true/false) then warn.
// Parens on the RHS are ignored.
llvm::APSInt Result;
if (RHS.get()->EvaluateAsInt(Result, Context))
if ((getLangOpts().Bool && !RHS.get()->getType()->isBooleanType() &&
!RHS.get()->getExprLoc().isMacroID()) ||
(Result != 0 && Result != 1)) {
Diag(Loc, diag::warn_logical_instead_of_bitwise)
<< RHS.get()->getSourceRange()
<< (Opc == BO_LAnd ? "&&" : "||");
// Suggest replacing the logical operator with the bitwise version
Diag(Loc, diag::note_logical_instead_of_bitwise_change_operator)
<< (Opc == BO_LAnd ? "&" : "|")
<< FixItHint::CreateReplacement(SourceRange(
Loc, getLocForEndOfToken(Loc)),
Opc == BO_LAnd ? "&" : "|");
if (Opc == BO_LAnd)
// Suggest replacing "Foo() && kNonZero" with "Foo()"
Diag(Loc, diag::note_logical_instead_of_bitwise_remove_constant)
<< FixItHint::CreateRemoval(
SourceRange(getLocForEndOfToken(LHS.get()->getLocEnd()),
RHS.get()->getLocEnd()));
}
}
if (!Context.getLangOpts().CPlusPlus) {
// OpenCL v1.1 s6.3.g: The logical operators and (&&), or (||) do
// not operate on the built-in scalar and vector float types.
if (Context.getLangOpts().OpenCL &&
Context.getLangOpts().OpenCLVersion < 120) {
if (LHS.get()->getType()->isFloatingType() ||
RHS.get()->getType()->isFloatingType())
return InvalidOperands(Loc, LHS, RHS);
}
LHS = UsualUnaryConversions(LHS.get());
if (LHS.isInvalid())
return QualType();
RHS = UsualUnaryConversions(RHS.get());
if (RHS.isInvalid())
return QualType();
if (!LHS.get()->getType()->isScalarType() ||
!RHS.get()->getType()->isScalarType())
return InvalidOperands(Loc, LHS, RHS);
return Context.IntTy;
}
// The following is safe because we only use this method for
// non-overloadable operands.
// C++ [expr.log.and]p1
// C++ [expr.log.or]p1
// The operands are both contextually converted to type bool.
ExprResult LHSRes = PerformContextuallyConvertToBool(LHS.get());
if (LHSRes.isInvalid())
return InvalidOperands(Loc, LHS, RHS);
LHS = LHSRes;
ExprResult RHSRes = PerformContextuallyConvertToBool(RHS.get());
if (RHSRes.isInvalid())
return InvalidOperands(Loc, LHS, RHS);
RHS = RHSRes;
// C++ [expr.log.and]p2
// C++ [expr.log.or]p2
// The result is a bool.
return Context.BoolTy;
}
static bool IsReadonlyMessage(Expr *E, Sema &S) {
const MemberExpr *ME = dyn_cast<MemberExpr>(E);
if (!ME) return false;
if (!isa<FieldDecl>(ME->getMemberDecl())) return false;
ObjCMessageExpr *Base = dyn_cast<ObjCMessageExpr>(
ME->getBase()->IgnoreImplicit()->IgnoreParenImpCasts());
if (!Base) return false;
return Base->getMethodDecl() != nullptr;
}
/// Is the given expression (which must be 'const') a reference to a
/// variable which was originally non-const, but which has become
/// 'const' due to being captured within a block?
enum NonConstCaptureKind { NCCK_None, NCCK_Block, NCCK_Lambda };
static NonConstCaptureKind isReferenceToNonConstCapture(Sema &S, Expr *E) {
assert(E->isLValue() && E->getType().isConstQualified());
E = E->IgnoreParens();
// Must be a reference to a declaration from an enclosing scope.
DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E);
if (!DRE) return NCCK_None;
if (!DRE->refersToEnclosingVariableOrCapture()) return NCCK_None;
// The declaration must be a variable which is not declared 'const'.
VarDecl *var = dyn_cast<VarDecl>(DRE->getDecl());
if (!var) return NCCK_None;
if (var->getType().isConstQualified()) return NCCK_None;
assert(var->hasLocalStorage() && "capture added 'const' to non-local?");
// Decide whether the first capture was for a block or a lambda.
DeclContext *DC = S.CurContext, *Prev = nullptr;
// Decide whether the first capture was for a block or a lambda.
while (DC) {
// For init-capture, it is possible that the variable belongs to the
// template pattern of the current context.
if (auto *FD = dyn_cast<FunctionDecl>(DC))
if (var->isInitCapture() &&
FD->getTemplateInstantiationPattern() == var->getDeclContext())
break;
if (DC == var->getDeclContext())
break;
Prev = DC;
DC = DC->getParent();
}
// Unless we have an init-capture, we've gone one step too far.
if (!var->isInitCapture())
DC = Prev;
return (isa<BlockDecl>(DC) ? NCCK_Block : NCCK_Lambda);
}
static bool IsTypeModifiable(QualType Ty, bool IsDereference) {
Ty = Ty.getNonReferenceType();
if (IsDereference && Ty->isPointerType())
Ty = Ty->getPointeeType();
return !Ty.isConstQualified();
}
// Update err_typecheck_assign_const and note_typecheck_assign_const
// when this enum is changed.
enum {
ConstFunction,
ConstVariable,
ConstMember,
ConstMethod,
NestedConstMember,
ConstUnknown, // Keep as last element
};
/// Emit the "read-only variable not assignable" error and print notes to give
/// more information about why the variable is not assignable, such as pointing
/// to the declaration of a const variable, showing that a method is const, or
/// that the function is returning a const reference.
static void DiagnoseConstAssignment(Sema &S, const Expr *E,
SourceLocation Loc) {
SourceRange ExprRange = E->getSourceRange();
// Only emit one error on the first const found. All other consts will emit
// a note to the error.
bool DiagnosticEmitted = false;
// Track if the current expression is the result of a dereference, and if the
// next checked expression is the result of a dereference.
bool IsDereference = false;
bool NextIsDereference = false;
// Loop to process MemberExpr chains.
while (true) {
IsDereference = NextIsDereference;
E = E->IgnoreImplicit()->IgnoreParenImpCasts();
if (const MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
NextIsDereference = ME->isArrow();
const ValueDecl *VD = ME->getMemberDecl();
if (const FieldDecl *Field = dyn_cast<FieldDecl>(VD)) {
// Mutable fields can be modified even if the class is const.
if (Field->isMutable()) {
assert(DiagnosticEmitted && "Expected diagnostic not emitted.");
break;
}
if (!IsTypeModifiable(Field->getType(), IsDereference)) {
if (!DiagnosticEmitted) {
S.Diag(Loc, diag::err_typecheck_assign_const)
<< ExprRange << ConstMember << false /*static*/ << Field
<< Field->getType();
DiagnosticEmitted = true;
}
S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
<< ConstMember << false /*static*/ << Field << Field->getType()
<< Field->getSourceRange();
}
E = ME->getBase();
continue;
} else if (const VarDecl *VDecl = dyn_cast<VarDecl>(VD)) {
if (VDecl->getType().isConstQualified()) {
if (!DiagnosticEmitted) {
S.Diag(Loc, diag::err_typecheck_assign_const)
<< ExprRange << ConstMember << true /*static*/ << VDecl
<< VDecl->getType();
DiagnosticEmitted = true;
}
S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
<< ConstMember << true /*static*/ << VDecl << VDecl->getType()
<< VDecl->getSourceRange();
}
// Static fields do not inherit constness from parents.
break;
}
break; // End MemberExpr
} else if (const ArraySubscriptExpr *ASE =
dyn_cast<ArraySubscriptExpr>(E)) {
E = ASE->getBase()->IgnoreParenImpCasts();
continue;
} else if (const ExtVectorElementExpr *EVE =
dyn_cast<ExtVectorElementExpr>(E)) {
E = EVE->getBase()->IgnoreParenImpCasts();
continue;
}
break;
}
if (const CallExpr *CE = dyn_cast<CallExpr>(E)) {
// Function calls
const FunctionDecl *FD = CE->getDirectCallee();
if (FD && !IsTypeModifiable(FD->getReturnType(), IsDereference)) {
if (!DiagnosticEmitted) {
S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange
<< ConstFunction << FD;
DiagnosticEmitted = true;
}
S.Diag(FD->getReturnTypeSourceRange().getBegin(),
diag::note_typecheck_assign_const)
<< ConstFunction << FD << FD->getReturnType()
<< FD->getReturnTypeSourceRange();
}
} else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
// Point to variable declaration.
if (const ValueDecl *VD = DRE->getDecl()) {
if (!IsTypeModifiable(VD->getType(), IsDereference)) {
if (!DiagnosticEmitted) {
S.Diag(Loc, diag::err_typecheck_assign_const)
<< ExprRange << ConstVariable << VD << VD->getType();
DiagnosticEmitted = true;
}
S.Diag(VD->getLocation(), diag::note_typecheck_assign_const)
<< ConstVariable << VD << VD->getType() << VD->getSourceRange();
}
}
} else if (isa<CXXThisExpr>(E)) {
if (const DeclContext *DC = S.getFunctionLevelDeclContext()) {
if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(DC)) {
if (MD->isConst()) {
if (!DiagnosticEmitted) {
S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange
<< ConstMethod << MD;
DiagnosticEmitted = true;
}
S.Diag(MD->getLocation(), diag::note_typecheck_assign_const)
<< ConstMethod << MD << MD->getSourceRange();
}
}
}
}
if (DiagnosticEmitted)
return;
// Can't determine a more specific message, so display the generic error.
S.Diag(Loc, diag::err_typecheck_assign_const) << ExprRange << ConstUnknown;
}
enum OriginalExprKind {
OEK_Variable,
OEK_Member,
OEK_LValue
};
static void DiagnoseRecursiveConstFields(Sema &S, const ValueDecl *VD,
const RecordType *Ty,
SourceLocation Loc, SourceRange Range,
OriginalExprKind OEK,
bool &DiagnosticEmitted,
bool IsNested = false) {
// We walk the record hierarchy breadth-first to ensure that we print
// diagnostics in field nesting order.
// First, check every field for constness.
for (const FieldDecl *Field : Ty->getDecl()->fields()) {
if (Field->getType().isConstQualified()) {
if (!DiagnosticEmitted) {
S.Diag(Loc, diag::err_typecheck_assign_const)
<< Range << NestedConstMember << OEK << VD
<< IsNested << Field;
DiagnosticEmitted = true;
}
S.Diag(Field->getLocation(), diag::note_typecheck_assign_const)
<< NestedConstMember << IsNested << Field
<< Field->getType() << Field->getSourceRange();
}
}
// Then, recurse.
for (const FieldDecl *Field : Ty->getDecl()->fields()) {
QualType FTy = Field->getType();
if (const RecordType *FieldRecTy = FTy->getAs<RecordType>())
DiagnoseRecursiveConstFields(S, VD, FieldRecTy, Loc, Range,
OEK, DiagnosticEmitted, true);
}
}
/// Emit an error for the case where a record we are trying to assign to has a
/// const-qualified field somewhere in its hierarchy.
static void DiagnoseRecursiveConstFields(Sema &S, const Expr *E,
SourceLocation Loc) {
QualType Ty = E->getType();
assert(Ty->isRecordType() && "lvalue was not record?");
SourceRange Range = E->getSourceRange();
const RecordType *RTy = Ty.getCanonicalType()->getAs<RecordType>();
bool DiagEmitted = false;
if (const MemberExpr *ME = dyn_cast<MemberExpr>(E))
DiagnoseRecursiveConstFields(S, ME->getMemberDecl(), RTy, Loc,
Range, OEK_Member, DiagEmitted);
else if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
DiagnoseRecursiveConstFields(S, DRE->getDecl(), RTy, Loc,
Range, OEK_Variable, DiagEmitted);
else
DiagnoseRecursiveConstFields(S, nullptr, RTy, Loc,
Range, OEK_LValue, DiagEmitted);
if (!DiagEmitted)
DiagnoseConstAssignment(S, E, Loc);
}
/// CheckForModifiableLvalue - Verify that E is a modifiable lvalue. If not,
/// emit an error and return true. If so, return false.
static bool CheckForModifiableLvalue(Expr *E, SourceLocation Loc, Sema &S) {
assert(!E->hasPlaceholderType(BuiltinType::PseudoObject));
S.CheckShadowingDeclModification(E, Loc);
SourceLocation OrigLoc = Loc;
Expr::isModifiableLvalueResult IsLV = E->isModifiableLvalue(S.Context,
&Loc);
if (IsLV == Expr::MLV_ClassTemporary && IsReadonlyMessage(E, S))
IsLV = Expr::MLV_InvalidMessageExpression;
if (IsLV == Expr::MLV_Valid)
return false;
unsigned DiagID = 0;
bool NeedType = false;
switch (IsLV) { // C99 6.5.16p2
case Expr::MLV_ConstQualified:
// Use a specialized diagnostic when we're assigning to an object
// from an enclosing function or block.
if (NonConstCaptureKind NCCK = isReferenceToNonConstCapture(S, E)) {
if (NCCK == NCCK_Block)
DiagID = diag::err_block_decl_ref_not_modifiable_lvalue;
else
DiagID = diag::err_lambda_decl_ref_not_modifiable_lvalue;
break;
}
// In ARC, use some specialized diagnostics for occasions where we
// infer 'const'. These are always pseudo-strong variables.
if (S.getLangOpts().ObjCAutoRefCount) {
DeclRefExpr *declRef = dyn_cast<DeclRefExpr>(E->IgnoreParenCasts());
if (declRef && isa<VarDecl>(declRef->getDecl())) {
VarDecl *var = cast<VarDecl>(declRef->getDecl());
// Use the normal diagnostic if it's pseudo-__strong but the
// user actually wrote 'const'.
if (var->isARCPseudoStrong() &&
(!var->getTypeSourceInfo() ||
!var->getTypeSourceInfo()->getType().isConstQualified())) {
// There are two pseudo-strong cases:
// - self
ObjCMethodDecl *method = S.getCurMethodDecl();
if (method && var == method->getSelfDecl())
DiagID = method->isClassMethod()
? diag::err_typecheck_arc_assign_self_class_method
: diag::err_typecheck_arc_assign_self;
// - fast enumeration variables
else
DiagID = diag::err_typecheck_arr_assign_enumeration;
SourceRange Assign;
if (Loc != OrigLoc)
Assign = SourceRange(OrigLoc, OrigLoc);
S.Diag(Loc, DiagID) << E->getSourceRange() << Assign;
// We need to preserve the AST regardless, so migration tool
// can do its job.
return false;
}
}
}
// If none of the special cases above are triggered, then this is a
// simple const assignment.
if (DiagID == 0) {
DiagnoseConstAssignment(S, E, Loc);
return true;
}
break;
case Expr::MLV_ConstAddrSpace:
DiagnoseConstAssignment(S, E, Loc);
return true;
case Expr::MLV_ConstQualifiedField:
DiagnoseRecursiveConstFields(S, E, Loc);
return true;
case Expr::MLV_ArrayType:
case Expr::MLV_ArrayTemporary:
DiagID = diag::err_typecheck_array_not_modifiable_lvalue;
NeedType = true;
break;
case Expr::MLV_NotObjectType:
DiagID = diag::err_typecheck_non_object_not_modifiable_lvalue;
NeedType = true;
break;
case Expr::MLV_LValueCast:
DiagID = diag::err_typecheck_lvalue_casts_not_supported;
break;
case Expr::MLV_Valid:
llvm_unreachable("did not take early return for MLV_Valid");
case Expr::MLV_InvalidExpression:
case Expr::MLV_MemberFunction:
case Expr::MLV_ClassTemporary:
DiagID = diag::err_typecheck_expression_not_modifiable_lvalue;
break;
case Expr::MLV_IncompleteType:
case Expr::MLV_IncompleteVoidType:
return S.RequireCompleteType(Loc, E->getType(),
diag::err_typecheck_incomplete_type_not_modifiable_lvalue, E);
case Expr::MLV_DuplicateVectorComponents:
DiagID = diag::err_typecheck_duplicate_vector_components_not_mlvalue;
break;
case Expr::MLV_NoSetterProperty:
llvm_unreachable("readonly properties should be processed differently");
case Expr::MLV_InvalidMessageExpression:
DiagID = diag::err_readonly_message_assignment;
break;
case Expr::MLV_SubObjCPropertySetting:
DiagID = diag::err_no_subobject_property_setting;
break;
}
SourceRange Assign;
if (Loc != OrigLoc)
Assign = SourceRange(OrigLoc, OrigLoc);
if (NeedType)
S.Diag(Loc, DiagID) << E->getType() << E->getSourceRange() << Assign;
else
S.Diag(Loc, DiagID) << E->getSourceRange() << Assign;
return true;
}
static void CheckIdentityFieldAssignment(Expr *LHSExpr, Expr *RHSExpr,
SourceLocation Loc,
Sema &Sema) {
if (Sema.inTemplateInstantiation())
return;
if (Sema.isUnevaluatedContext())
return;
if (Loc.isInvalid() || Loc.isMacroID())
return;
if (LHSExpr->getExprLoc().isMacroID() || RHSExpr->getExprLoc().isMacroID())
return;
// C / C++ fields
MemberExpr *ML = dyn_cast<MemberExpr>(LHSExpr);
MemberExpr *MR = dyn_cast<MemberExpr>(RHSExpr);
if (ML && MR) {
if (!(isa<CXXThisExpr>(ML->getBase()) && isa<CXXThisExpr>(MR->getBase())))
return;
const ValueDecl *LHSDecl =
cast<ValueDecl>(ML->getMemberDecl()->getCanonicalDecl());
const ValueDecl *RHSDecl =
cast<ValueDecl>(MR->getMemberDecl()->getCanonicalDecl());
if (LHSDecl != RHSDecl)
return;
if (LHSDecl->getType().isVolatileQualified())
return;
if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>())
if (RefTy->getPointeeType().isVolatileQualified())
return;
Sema.Diag(Loc, diag::warn_identity_field_assign) << 0;
}
// Objective-C instance variables
ObjCIvarRefExpr *OL = dyn_cast<ObjCIvarRefExpr>(LHSExpr);
ObjCIvarRefExpr *OR = dyn_cast<ObjCIvarRefExpr>(RHSExpr);
if (OL && OR && OL->getDecl() == OR->getDecl()) {
DeclRefExpr *RL = dyn_cast<DeclRefExpr>(OL->getBase()->IgnoreImpCasts());
DeclRefExpr *RR = dyn_cast<DeclRefExpr>(OR->getBase()->IgnoreImpCasts());
if (RL && RR && RL->getDecl() == RR->getDecl())
Sema.Diag(Loc, diag::warn_identity_field_assign) << 1;
}
}
// C99 6.5.16.1
QualType Sema::CheckAssignmentOperands(Expr *LHSExpr, ExprResult &RHS,
SourceLocation Loc,
QualType CompoundType) {
assert(!LHSExpr->hasPlaceholderType(BuiltinType::PseudoObject));
// Verify that LHS is a modifiable lvalue, and emit error if not.
if (CheckForModifiableLvalue(LHSExpr, Loc, *this))
return QualType();
QualType LHSType = LHSExpr->getType();
QualType RHSType = CompoundType.isNull() ? RHS.get()->getType() :
CompoundType;
// OpenCL v1.2 s6.1.1.1 p2:
// The half data type can only be used to declare a pointer to a buffer that
// contains half values
if (getLangOpts().OpenCL && !getOpenCLOptions().isEnabled("cl_khr_fp16") &&
LHSType->isHalfType()) {
Diag(Loc, diag::err_opencl_half_load_store) << 1
<< LHSType.getUnqualifiedType();
return QualType();
}
AssignConvertType ConvTy;
if (CompoundType.isNull()) {
Expr *RHSCheck = RHS.get();
CheckIdentityFieldAssignment(LHSExpr, RHSCheck, Loc, *this);
QualType LHSTy(LHSType);
ConvTy = CheckSingleAssignmentConstraints(LHSTy, RHS);
if (RHS.isInvalid())
return QualType();
// Special case of NSObject attributes on c-style pointer types.
if (ConvTy == IncompatiblePointer &&
((Context.isObjCNSObjectType(LHSType) &&
RHSType->isObjCObjectPointerType()) ||
(Context.isObjCNSObjectType(RHSType) &&
LHSType->isObjCObjectPointerType())))
ConvTy = Compatible;
if (ConvTy == Compatible &&
LHSType->isObjCObjectType())
Diag(Loc, diag::err_objc_object_assignment)
<< LHSType;
// If the RHS is a unary plus or minus, check to see if they = and + are
// right next to each other. If so, the user may have typo'd "x =+ 4"
// instead of "x += 4".
if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(RHSCheck))
RHSCheck = ICE->getSubExpr();
if (UnaryOperator *UO = dyn_cast<UnaryOperator>(RHSCheck)) {
if ((UO->getOpcode() == UO_Plus ||
UO->getOpcode() == UO_Minus) &&
Loc.isFileID() && UO->getOperatorLoc().isFileID() &&
// Only if the two operators are exactly adjacent.
Loc.getLocWithOffset(1) == UO->getOperatorLoc() &&
// And there is a space or other character before the subexpr of the
// unary +/-. We don't want to warn on "x=-1".
Loc.getLocWithOffset(2) != UO->getSubExpr()->getLocStart() &&
UO->getSubExpr()->getLocStart().isFileID()) {
Diag(Loc, diag::warn_not_compound_assign)
<< (UO->getOpcode() == UO_Plus ? "+" : "-")
<< SourceRange(UO->getOperatorLoc(), UO->getOperatorLoc());
}
}
if (ConvTy == Compatible) {
if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong) {
// Warn about retain cycles where a block captures the LHS, but
// not if the LHS is a simple variable into which the block is
// being stored...unless that variable can be captured by reference!
const Expr *InnerLHS = LHSExpr->IgnoreParenCasts();
const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(InnerLHS);
if (!DRE || DRE->getDecl()->hasAttr<BlocksAttr>())
checkRetainCycles(LHSExpr, RHS.get());
}
if (LHSType.getObjCLifetime() == Qualifiers::OCL_Strong ||
LHSType.isNonWeakInMRRWithObjCWeak(Context)) {
// It is safe to assign a weak reference into a strong variable.
// Although this code can still have problems:
// id x = self.weakProp;
// id y = self.weakProp;
// we do not warn to warn spuriously when 'x' and 'y' are on separate
// paths through the function. This should be revisited if
// -Wrepeated-use-of-weak is made flow-sensitive.
// For ObjCWeak only, we do not warn if the assign is to a non-weak
// variable, which will be valid for the current autorelease scope.
if (!Diags.isIgnored(diag::warn_arc_repeated_use_of_weak,
RHS.get()->getLocStart()))
getCurFunction()->markSafeWeakUse(RHS.get());
} else if (getLangOpts().ObjCAutoRefCount || getLangOpts().ObjCWeak) {
checkUnsafeExprAssigns(Loc, LHSExpr, RHS.get());
}
}
} else {
// Compound assignment "x += y"
ConvTy = CheckAssignmentConstraints(Loc, LHSType, RHSType);
}
if (DiagnoseAssignmentResult(ConvTy, Loc, LHSType, RHSType,
RHS.get(), AA_Assigning))
return QualType();
CheckForNullPointerDereference(*this, LHSExpr);
// C99 6.5.16p3: The type of an assignment expression is the type of the
// left operand unless the left operand has qualified type, in which case
// it is the unqualified version of the type of the left operand.
// C99 6.5.16.1p2: In simple assignment, the value of the right operand
// is converted to the type of the assignment expression (above).
// C++ 5.17p1: the type of the assignment expression is that of its left
// operand.
return (getLangOpts().CPlusPlus
? LHSType : LHSType.getUnqualifiedType());
}
// Only ignore explicit casts to void.
static bool IgnoreCommaOperand(const Expr *E) {
E = E->IgnoreParens();
if (const CastExpr *CE = dyn_cast<CastExpr>(E)) {
if (CE->getCastKind() == CK_ToVoid) {
return true;
}
}
return false;
}
// Look for instances where it is likely the comma operator is confused with
// another operator. There is a whitelist of acceptable expressions for the
// left hand side of the comma operator, otherwise emit a warning.
void Sema::DiagnoseCommaOperator(const Expr *LHS, SourceLocation Loc) {
// No warnings in macros
if (Loc.isMacroID())
return;
// Don't warn in template instantiations.
if (inTemplateInstantiation())
return;
// Scope isn't fine-grained enough to whitelist the specific cases, so
// instead, skip more than needed, then call back into here with the
// CommaVisitor in SemaStmt.cpp.
// The whitelisted locations are the initialization and increment portions
// of a for loop. The additional checks are on the condition of
// if statements, do/while loops, and for loops.
const unsigned ForIncrementFlags =
Scope::ControlScope | Scope::ContinueScope | Scope::BreakScope;
const unsigned ForInitFlags = Scope::ControlScope | Scope::DeclScope;
const unsigned ScopeFlags = getCurScope()->getFlags();
if ((ScopeFlags & ForIncrementFlags) == ForIncrementFlags ||
(ScopeFlags & ForInitFlags) == ForInitFlags)
return;
// If there are multiple comma operators used together, get the RHS of the
// of the comma operator as the LHS.
while (const BinaryOperator *BO = dyn_cast<BinaryOperator>(LHS)) {
if (BO->getOpcode() != BO_Comma)
break;
LHS = BO->getRHS();
}
// Only allow some expressions on LHS to not warn.
if (IgnoreCommaOperand(LHS))
return;
Diag(Loc, diag::warn_comma_operator);
Diag(LHS->getLocStart(), diag::note_cast_to_void)
<< LHS->getSourceRange()
<< FixItHint::CreateInsertion(LHS->getLocStart(),
LangOpts.CPlusPlus ? "static_cast<void>("
: "(void)(")
<< FixItHint::CreateInsertion(PP.getLocForEndOfToken(LHS->getLocEnd()),
")");
}
// C99 6.5.17
static QualType CheckCommaOperands(Sema &S, ExprResult &LHS, ExprResult &RHS,
SourceLocation Loc) {
LHS = S.CheckPlaceholderExpr(LHS.get());
RHS = S.CheckPlaceholderExpr(RHS.get());
if (LHS.isInvalid() || RHS.isInvalid())
return QualType();
// C's comma performs lvalue conversion (C99 6.3.2.1) on both its
// operands, but not unary promotions.
// C++'s comma does not do any conversions at all (C++ [expr.comma]p1).
// So we treat the LHS as a ignored value, and in C++ we allow the
// containing site to determine what should be done with the RHS.
LHS = S.IgnoredValueConversions(LHS.get());
if (LHS.isInvalid())
return QualType();
S.DiagnoseUnusedExprResult(LHS.get());
if (!S.getLangOpts().CPlusPlus) {
RHS = S.DefaultFunctionArrayLvalueConversion(RHS.get());
if (RHS.isInvalid())
return QualType();
if (!RHS.get()->getType()->isVoidType())
S.RequireCompleteType(Loc, RHS.get()->getType(),
diag::err_incomplete_type);
}
if (!S.getDiagnostics().isIgnored(diag::warn_comma_operator, Loc))
S.DiagnoseCommaOperator(LHS.get(), Loc);
return RHS.get()->getType();
}
/// CheckIncrementDecrementOperand - unlike most "Check" methods, this routine
/// doesn't need to call UsualUnaryConversions or UsualArithmeticConversions.
static QualType CheckIncrementDecrementOperand(Sema &S, Expr *Op,
ExprValueKind &VK,
ExprObjectKind &OK,
SourceLocation OpLoc,
bool IsInc, bool IsPrefix) {
if (Op->isTypeDependent())
return S.Context.DependentTy;
QualType ResType = Op->getType();
// Atomic types can be used for increment / decrement where the non-atomic
// versions can, so ignore the _Atomic() specifier for the purpose of
// checking.
if (const AtomicType *ResAtomicType = ResType->getAs<AtomicType>())
ResType = ResAtomicType->getValueType();
assert(!ResType.isNull() && "no type for increment/decrement expression");
if (S.getLangOpts().CPlusPlus && ResType->isBooleanType()) {
// Decrement of bool is not allowed.
if (!IsInc) {
S.Diag(OpLoc, diag::err_decrement_bool) << Op->getSourceRange();
return QualType();
}
// Increment of bool sets it to true, but is deprecated.
S.Diag(OpLoc, S.getLangOpts().CPlusPlus17 ? diag::ext_increment_bool
: diag::warn_increment_bool)
<< Op->getSourceRange();
} else if (S.getLangOpts().CPlusPlus && ResType->isEnumeralType()) {
// Error on enum increments and decrements in C++ mode
S.Diag(OpLoc, diag::err_increment_decrement_enum) << IsInc << ResType;
return QualType();
} else if (ResType->isRealType()) {
// OK!
} else if (ResType->isPointerType()) {
// C99 6.5.2.4p2, 6.5.6p2
if (!checkArithmeticOpPointerOperand(S, OpLoc, Op))
return QualType();
} else if (ResType->isObjCObjectPointerType()) {
// On modern runtimes, ObjC pointer arithmetic is forbidden.
// Otherwise, we just need a complete type.
if (checkArithmeticIncompletePointerType(S, OpLoc, Op) ||
checkArithmeticOnObjCPointer(S, OpLoc, Op))
return QualType();
} else if (ResType->isAnyComplexType()) {
// C99 does not support ++/-- on complex types, we allow as an extension.
S.Diag(OpLoc, diag::ext_integer_increment_complex)
<< ResType << Op->getSourceRange();
} else if (ResType->isPlaceholderType()) {
ExprResult PR = S.CheckPlaceholderExpr(Op);
if (PR.isInvalid()) return QualType();
return CheckIncrementDecrementOperand(S, PR.get(), VK, OK, OpLoc,
IsInc, IsPrefix);
} else if (S.getLangOpts().AltiVec && ResType->isVectorType()) {
// OK! ( C/C++ Language Extensions for CBEA(Version 2.6) 10.3 )
} else if (S.getLangOpts().ZVector && ResType->isVectorType() &&
(ResType->getAs<VectorType>()->getVectorKind() !=
VectorType::AltiVecBool)) {
// The z vector extensions allow ++ and -- for non-bool vectors.
} else if(S.getLangOpts().OpenCL && ResType->isVectorType() &&
ResType->getAs<VectorType>()->getElementType()->isIntegerType()) {
// OpenCL V1.2 6.3 says dec/inc ops operate on integer vector types.
} else {
S.Diag(OpLoc, diag::err_typecheck_illegal_increment_decrement)
<< ResType << int(IsInc) << Op->getSourceRange();
return QualType();
}
// At this point, we know we have a real, complex or pointer type.
// Now make sure the operand is a modifiable lvalue.
if (CheckForModifiableLvalue(Op, OpLoc, S))
return QualType();
// In C++, a prefix increment is the same type as the operand. Otherwise
// (in C or with postfix), the increment is the unqualified type of the
// operand.
if (IsPrefix && S.getLangOpts().CPlusPlus) {
VK = VK_LValue;
OK = Op->getObjectKind();
return ResType;
} else {
VK = VK_RValue;
return ResType.getUnqualifiedType();
}
}
/// getPrimaryDecl - Helper function for CheckAddressOfOperand().
/// This routine allows us to typecheck complex/recursive expressions
/// where the declaration is needed for type checking. We only need to
/// handle cases when the expression references a function designator
/// or is an lvalue. Here are some examples:
/// - &(x) => x
/// - &*****f => f for f a function designator.
/// - &s.xx => s
/// - &s.zz[1].yy -> s, if zz is an array
/// - *(x + 1) -> x, if x is an array
/// - &"123"[2] -> 0
/// - & __real__ x -> x
static ValueDecl *getPrimaryDecl(Expr *E) {
switch (E->getStmtClass()) {
case Stmt::DeclRefExprClass:
return cast<DeclRefExpr>(E)->getDecl();
case Stmt::MemberExprClass:
// If this is an arrow operator, the address is an offset from
// the base's value, so the object the base refers to is
// irrelevant.
if (cast<MemberExpr>(E)->isArrow())
return nullptr;
// Otherwise, the expression refers to a part of the base
return getPrimaryDecl(cast<MemberExpr>(E)->getBase());
case Stmt::ArraySubscriptExprClass: {
// FIXME: This code shouldn't be necessary! We should catch the implicit
// promotion of register arrays earlier.
Expr* Base = cast<ArraySubscriptExpr>(E)->getBase();
if (ImplicitCastExpr* ICE = dyn_cast<ImplicitCastExpr>(Base)) {
if (ICE->getSubExpr()->getType()->isArrayType())
return getPrimaryDecl(ICE->getSubExpr());
}
return nullptr;
}
case Stmt::UnaryOperatorClass: {
UnaryOperator *UO = cast<UnaryOperator>(E);
switch(UO->getOpcode()) {
case UO_Real:
case UO_Imag:
case UO_Extension:
return getPrimaryDecl(UO->getSubExpr());
default:
return nullptr;
}
}
case Stmt::ParenExprClass:
return getPrimaryDecl(cast<ParenExpr>(E)->getSubExpr());
case Stmt::ImplicitCastExprClass:
// If the result of an implicit cast is an l-value, we care about
// the sub-expression; otherwise, the result here doesn't matter.
return getPrimaryDecl(cast<ImplicitCastExpr>(E)->getSubExpr());
default:
return nullptr;
}
}
namespace {
enum {
AO_Bit_Field = 0,
AO_Vector_Element = 1,
AO_Property_Expansion = 2,
AO_Register_Variable = 3,
AO_No_Error = 4
};
}
/// Diagnose invalid operand for address of operations.
///
/// \param Type The type of operand which cannot have its address taken.
static void diagnoseAddressOfInvalidType(Sema &S, SourceLocation Loc,
Expr *E, unsigned Type) {
S.Diag(Loc, diag::err_typecheck_address_of) << Type << E->getSourceRange();
}
/// CheckAddressOfOperand - The operand of & must be either a function
/// designator or an lvalue designating an object. If it is an lvalue, the
/// object cannot be declared with storage class register or be a bit field.
/// Note: The usual conversions are *not* applied to the operand of the &
/// operator (C99 6.3.2.1p[2-4]), and its result is never an lvalue.
/// In C++, the operand might be an overloaded function name, in which case
/// we allow the '&' but retain the overloaded-function type.
QualType Sema::CheckAddressOfOperand(ExprResult &OrigOp, SourceLocation OpLoc) {
if (const BuiltinType *PTy = OrigOp.get()->getType()->getAsPlaceholderType()){
if (PTy->getKind() == BuiltinType::Overload) {
Expr *E = OrigOp.get()->IgnoreParens();
if (!isa<OverloadExpr>(E)) {
assert(cast<UnaryOperator>(E)->getOpcode() == UO_AddrOf);
Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof_addrof_function)
<< OrigOp.get()->getSourceRange();
return QualType();
}
OverloadExpr *Ovl = cast<OverloadExpr>(E);
if (isa<UnresolvedMemberExpr>(Ovl))
if (!ResolveSingleFunctionTemplateSpecialization(Ovl)) {
Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
<< OrigOp.get()->getSourceRange();
return QualType();
}
return Context.OverloadTy;
}
if (PTy->getKind() == BuiltinType::UnknownAny)
return Context.UnknownAnyTy;
if (PTy->getKind() == BuiltinType::BoundMember) {
Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
<< OrigOp.get()->getSourceRange();
return QualType();
}
OrigOp = CheckPlaceholderExpr(OrigOp.get());
if (OrigOp.isInvalid()) return QualType();
}
if (OrigOp.get()->isTypeDependent())
return Context.DependentTy;
assert(!OrigOp.get()->getType()->isPlaceholderType());
// Make sure to ignore parentheses in subsequent checks
Expr *op = OrigOp.get()->IgnoreParens();
// In OpenCL captures for blocks called as lambda functions
// are located in the private address space. Blocks used in
// enqueue_kernel can be located in a different address space
// depending on a vendor implementation. Thus preventing
// taking an address of the capture to avoid invalid AS casts.
if (LangOpts.OpenCL) {
auto* VarRef = dyn_cast<DeclRefExpr>(op);
if (VarRef && VarRef->refersToEnclosingVariableOrCapture()) {
Diag(op->getExprLoc(), diag::err_opencl_taking_address_capture);
return QualType();
}
}
if (getLangOpts().C99) {
// Implement C99-only parts of addressof rules.
if (UnaryOperator* uOp = dyn_cast<UnaryOperator>(op)) {
if (uOp->getOpcode() == UO_Deref)
// Per C99 6.5.3.2, the address of a deref always returns a valid result
// (assuming the deref expression is valid).
return uOp->getSubExpr()->getType();
}
// Technically, there should be a check for array subscript
// expressions here, but the result of one is always an lvalue anyway.
}
ValueDecl *dcl = getPrimaryDecl(op);
if (auto *FD = dyn_cast_or_null<FunctionDecl>(dcl))
if (!checkAddressOfFunctionIsAvailable(FD, /*Complain=*/true,
op->getLocStart()))
return QualType();
Expr::LValueClassification lval = op->ClassifyLValue(Context);
unsigned AddressOfError = AO_No_Error;
if (lval == Expr::LV_ClassTemporary || lval == Expr::LV_ArrayTemporary) {
bool sfinae = (bool)isSFINAEContext();
Diag(OpLoc, isSFINAEContext() ? diag::err_typecheck_addrof_temporary
: diag::ext_typecheck_addrof_temporary)
<< op->getType() << op->getSourceRange();
if (sfinae)
return QualType();
// Materialize the temporary as an lvalue so that we can take its address.
OrigOp = op =
CreateMaterializeTemporaryExpr(op->getType(), OrigOp.get(), true);
} else if (isa<ObjCSelectorExpr>(op)) {
return Context.getPointerType(op->getType());
} else if (lval == Expr::LV_MemberFunction) {
// If it's an instance method, make a member pointer.
// The expression must have exactly the form &A::foo.
// If the underlying expression isn't a decl ref, give up.
if (!isa<DeclRefExpr>(op)) {
Diag(OpLoc, diag::err_invalid_form_pointer_member_function)
<< OrigOp.get()->getSourceRange();
return QualType();
}
DeclRefExpr *DRE = cast<DeclRefExpr>(op);
CXXMethodDecl *MD = cast<CXXMethodDecl>(DRE->getDecl());
// The id-expression was parenthesized.
if (OrigOp.get() != DRE) {
Diag(OpLoc, diag::err_parens_pointer_member_function)
<< OrigOp.get()->getSourceRange();
// The method was named without a qualifier.
} else if (!DRE->getQualifier()) {
if (MD->getParent()->getName().empty())
Diag(OpLoc, diag::err_unqualified_pointer_member_function)
<< op->getSourceRange();
else {
SmallString<32> Str;
StringRef Qual = (MD->getParent()->getName() + "::").toStringRef(Str);
Diag(OpLoc, diag::err_unqualified_pointer_member_function)
<< op->getSourceRange()
<< FixItHint::CreateInsertion(op->getSourceRange().getBegin(), Qual);
}
}
// Taking the address of a dtor is illegal per C++ [class.dtor]p2.
if (isa<CXXDestructorDecl>(MD))
Diag(OpLoc, diag::err_typecheck_addrof_dtor) << op->getSourceRange();
QualType MPTy = Context.getMemberPointerType(
op->getType(), Context.getTypeDeclType(MD->getParent()).getTypePtr());
// Under the MS ABI, lock down the inheritance model now.
if (Context.getTargetInfo().getCXXABI().isMicrosoft())
(void)isCompleteType(OpLoc, MPTy);
return MPTy;
} else if (lval != Expr::LV_Valid && lval != Expr::LV_IncompleteVoidType) {
// C99 6.5.3.2p1
// The operand must be either an l-value or a function designator
if (!op->getType()->isFunctionType()) {
// Use a special diagnostic for loads from property references.
if (isa<PseudoObjectExpr>(op)) {
AddressOfError = AO_Property_Expansion;
} else {
Diag(OpLoc, diag::err_typecheck_invalid_lvalue_addrof)
<< op->getType() << op->getSourceRange();
return QualType();
}
}
} else if (op->getObjectKind() == OK_BitField) { // C99 6.5.3.2p1
// The operand cannot be a bit-field
AddressOfError = AO_Bit_Field;
} else if (op->getObjectKind() == OK_VectorComponent) {
// The operand cannot be an element of a vector
AddressOfError = AO_Vector_Element;
} else if (dcl) { // C99 6.5.3.2p1
// We have an lvalue with a decl. Make sure the decl is not declared
// with the register storage-class specifier.
if (const VarDecl *vd = dyn_cast<VarDecl>(dcl)) {
// in C++ it is not error to take address of a register
// variable (c++03 7.1.1P3)
if (vd->getStorageClass() == SC_Register &&
!getLangOpts().CPlusPlus) {
AddressOfError = AO_Register_Variable;
}
} else if (isa<MSPropertyDecl>(dcl)) {
AddressOfError = AO_Property_Expansion;
} else if (isa<FunctionTemplateDecl>(dcl)) {
return Context.OverloadTy;
} else if (isa<FieldDecl>(dcl) || isa<IndirectFieldDecl>(dcl)) {
// Okay: we can take the address of a field.
// Could be a pointer to member, though, if there is an explicit
// scope qualifier for the class.
if (isa<DeclRefExpr>(op) && cast<DeclRefExpr>(op)->getQualifier()) {
DeclContext *Ctx = dcl->getDeclContext();
if (Ctx && Ctx->isRecord()) {
if (dcl->getType()->isReferenceType()) {
Diag(OpLoc,
diag::err_cannot_form_pointer_to_member_of_reference_type)
<< dcl->getDeclName() << dcl->getType();
return QualType();
}
while (cast<RecordDecl>(Ctx)->isAnonymousStructOrUnion())
Ctx = Ctx->getParent();
QualType MPTy = Context.getMemberPointerType(
op->getType(),
Context.getTypeDeclType(cast<RecordDecl>(Ctx)).getTypePtr());
// Under the MS ABI, lock down the inheritance model now.
if (Context.getTargetInfo().getCXXABI().isMicrosoft())
(void)isCompleteType(OpLoc, MPTy);
return MPTy;
}
}
} else if (!isa<FunctionDecl>(dcl) && !isa<NonTypeTemplateParmDecl>(dcl) &&
!isa<BindingDecl>(dcl))
llvm_unreachable("Unknown/unexpected decl type");
}
if (AddressOfError != AO_No_Error) {
diagnoseAddressOfInvalidType(*this, OpLoc, op, AddressOfError);
return QualType();
}
if (lval == Expr::LV_IncompleteVoidType) {
// Taking the address of a void variable is technically illegal, but we
// allow it in cases which are otherwise valid.
// Example: "extern void x; void* y = &x;".
Diag(OpLoc, diag::ext_typecheck_addrof_void) << op->getSourceRange();
}
// If the operand has type "type", the result has type "pointer to type".
if (op->getType()->isObjCObjectType())
return Context.getObjCObjectPointerType(op->getType());
CheckAddressOfPackedMember(op);
return Context.getPointerType(op->getType());
}
static void RecordModifiableNonNullParam(Sema &S, const Expr *Exp) {
const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Exp);
if (!DRE)
return;
const Decl *D = DRE->getDecl();
if (!D)
return;
const ParmVarDecl *Param = dyn_cast<ParmVarDecl>(D);
if (!Param)
return;
if (const FunctionDecl* FD = dyn_cast<FunctionDecl>(Param->getDeclContext()))
if (!FD->hasAttr<NonNullAttr>() && !Param->hasAttr<NonNullAttr>())
return;
if (FunctionScopeInfo *FD = S.getCurFunction())
if (!FD->ModifiedNonNullParams.count(Param))
FD->ModifiedNonNullParams.insert(Param);
}
/// CheckIndirectionOperand - Type check unary indirection (prefix '*').
static QualType CheckIndirectionOperand(Sema &S, Expr *Op, ExprValueKind &VK,
SourceLocation OpLoc) {
if (Op->isTypeDependent())
return S.Context.DependentTy;
ExprResult ConvResult = S.UsualUnaryConversions(Op);
if (ConvResult.isInvalid())
return QualType();
Op = ConvResult.get();
QualType OpTy = Op->getType();
QualType Result;
if (isa<CXXReinterpretCastExpr>(Op)) {
QualType OpOrigType = Op->IgnoreParenCasts()->getType();
S.CheckCompatibleReinterpretCast(OpOrigType, OpTy, /*IsDereference*/true,
Op->getSourceRange());
}
if (const PointerType *PT = OpTy->getAs<PointerType>())
{
Result = PT->getPointeeType();
}
else if (const ObjCObjectPointerType *OPT =
OpTy->getAs<ObjCObjectPointerType>())
Result = OPT->getPointeeType();
else {
ExprResult PR = S.CheckPlaceholderExpr(Op);
if (PR.isInvalid()) return QualType();
if (PR.get() != Op)
return CheckIndirectionOperand(S, PR.get(), VK, OpLoc);
}
if (Result.isNull()) {
S.Diag(OpLoc, diag::err_typecheck_indirection_requires_pointer)
<< OpTy << Op->getSourceRange();
return QualType();
}
// Note that per both C89 and C99, indirection is always legal, even if Result
// is an incomplete type or void. It would be possible to warn about
// dereferencing a void pointer, but it's completely well-defined, and such a
// warning is unlikely to catch any mistakes. In C++, indirection is not valid
// for pointers to 'void' but is fine for any other pointer type:
//
// C++ [expr.unary.op]p1:
// [...] the expression to which [the unary * operator] is applied shall
// be a pointer to an object type, or a pointer to a function type
if (S.getLangOpts().CPlusPlus && Result->isVoidType())
S.Diag(OpLoc, diag::ext_typecheck_indirection_through_void_pointer)
<< OpTy << Op->getSourceRange();
// Dereferences are usually l-values...
VK = VK_LValue;
// ...except that certain expressions are never l-values in C.
if (!S.getLangOpts().CPlusPlus && Result.isCForbiddenLValueType())
VK = VK_RValue;
return Result;
}
BinaryOperatorKind Sema::ConvertTokenKindToBinaryOpcode(tok::TokenKind Kind) {
BinaryOperatorKind Opc;
switch (Kind) {
default: llvm_unreachable("Unknown binop!");
case tok::periodstar: Opc = BO_PtrMemD; break;
case tok::arrowstar: Opc = BO_PtrMemI; break;
case tok::star: Opc = BO_Mul; break;
case tok::slash: Opc = BO_Div; break;
case tok::percent: Opc = BO_Rem; break;
case tok::plus: Opc = BO_Add; break;
case tok::minus: Opc = BO_Sub; break;
case tok::lessless: Opc = BO_Shl; break;
case tok::greatergreater: Opc = BO_Shr; break;
case tok::lessequal: Opc = BO_LE; break;
case tok::less: Opc = BO_LT; break;
case tok::greaterequal: Opc = BO_GE; break;
case tok::greater: Opc = BO_GT; break;
case tok::exclaimequal: Opc = BO_NE; break;
case tok::equalequal: Opc = BO_EQ; break;
case tok::spaceship: Opc = BO_Cmp; break;
case tok::amp: Opc = BO_And; break;
case tok::caret: Opc = BO_Xor; break;
case tok::pipe: Opc = BO_Or; break;
case tok::ampamp: Opc = BO_LAnd; break;
case tok::pipepipe: Opc = BO_LOr; break;
case tok::equal: Opc = BO_Assign; break;
case tok::starequal: Opc = BO_MulAssign; break;
case tok::slashequal: Opc = BO_DivAssign; break;
case tok::percentequal: Opc = BO_RemAssign; break;
case tok::plusequal: Opc = BO_AddAssign; break;
case tok::minusequal: Opc = BO_SubAssign; break;
case tok::lesslessequal: Opc = BO_ShlAssign; break;
case tok::greatergreaterequal: Opc = BO_ShrAssign; break;
case tok::ampequal: Opc = BO_AndAssign; break;
case tok::caretequal: Opc = BO_XorAssign; break;
case tok::pipeequal: Opc = BO_OrAssign; break;
case tok::comma: Opc = BO_Comma; break;
}
return Opc;
}
static inline UnaryOperatorKind ConvertTokenKindToUnaryOpcode(
tok::TokenKind Kind) {
UnaryOperatorKind Opc;
switch (Kind) {
default: llvm_unreachable("Unknown unary op!");
case tok::plusplus: Opc = UO_PreInc; break;
case tok::minusminus: Opc = UO_PreDec; break;
case tok::amp: Opc = UO_AddrOf; break;
case tok::star: Opc = UO_Deref; break;
case tok::plus: Opc = UO_Plus; break;
case tok::minus: Opc = UO_Minus; break;
case tok::tilde: Opc = UO_Not; break;
case tok::exclaim: Opc = UO_LNot; break;
case tok::kw___real: Opc = UO_Real; break;
case tok::kw___imag: Opc = UO_Imag; break;
case tok::kw___extension__: Opc = UO_Extension; break;
}
return Opc;
}
/// DiagnoseSelfAssignment - Emits a warning if a value is assigned to itself.
/// This warning suppressed in the event of macro expansions.
static void DiagnoseSelfAssignment(Sema &S, Expr *LHSExpr, Expr *RHSExpr,
SourceLocation OpLoc, bool IsBuiltin) {
if (S.inTemplateInstantiation())
return;
if (S.isUnevaluatedContext())
return;
if (OpLoc.isInvalid() || OpLoc.isMacroID())
return;
LHSExpr = LHSExpr->IgnoreParenImpCasts();
RHSExpr = RHSExpr->IgnoreParenImpCasts();
const DeclRefExpr *LHSDeclRef = dyn_cast<DeclRefExpr>(LHSExpr);
const DeclRefExpr *RHSDeclRef = dyn_cast<DeclRefExpr>(RHSExpr);
if (!LHSDeclRef || !RHSDeclRef ||
LHSDeclRef->getLocation().isMacroID() ||
RHSDeclRef->getLocation().isMacroID())
return;
const ValueDecl *LHSDecl =
cast<ValueDecl>(LHSDeclRef->getDecl()->getCanonicalDecl());
const ValueDecl *RHSDecl =
cast<ValueDecl>(RHSDeclRef->getDecl()->getCanonicalDecl());
if (LHSDecl != RHSDecl)
return;
if (LHSDecl->getType().isVolatileQualified())
return;
if (const ReferenceType *RefTy = LHSDecl->getType()->getAs<ReferenceType>())
if (RefTy->getPointeeType().isVolatileQualified())
return;
S.Diag(OpLoc, IsBuiltin ? diag::warn_self_assignment_builtin
: diag::warn_self_assignment_overloaded)
<< LHSDeclRef->getType() << LHSExpr->getSourceRange()
<< RHSExpr->getSourceRange();
}
/// Check if a bitwise-& is performed on an Objective-C pointer. This
/// is usually indicative of introspection within the Objective-C pointer.
static void checkObjCPointerIntrospection(Sema &S, ExprResult &L, ExprResult &R,
SourceLocation OpLoc) {
if (!S.getLangOpts().ObjC1)
return;
const Expr *ObjCPointerExpr = nullptr, *OtherExpr = nullptr;
const Expr *LHS = L.get();
const Expr *RHS = R.get();
if (LHS->IgnoreParenCasts()->getType()->isObjCObjectPointerType()) {
ObjCPointerExpr = LHS;
OtherExpr = RHS;
}
else if (RHS->IgnoreParenCasts()->getType()->isObjCObjectPointerType()) {
ObjCPointerExpr = RHS;
OtherExpr = LHS;
}
// This warning is deliberately made very specific to reduce false
// positives with logic that uses '&' for hashing. This logic mainly
// looks for code trying to introspect into tagged pointers, which
// code should generally never do.
if (ObjCPointerExpr && isa<IntegerLiteral>(OtherExpr->IgnoreParenCasts())) {
unsigned Diag = diag::warn_objc_pointer_masking;
// Determine if we are introspecting the result of performSelectorXXX.
const Expr *Ex = ObjCPointerExpr->IgnoreParenCasts();
// Special case messages to -performSelector and friends, which
// can return non-pointer values boxed in a pointer value.
// Some clients may wish to silence warnings in this subcase.
if (const ObjCMessageExpr *ME = dyn_cast<ObjCMessageExpr>(Ex)) {
Selector S = ME->getSelector();
StringRef SelArg0 = S.getNameForSlot(0);
if (SelArg0.startswith("performSelector"))
Diag = diag::warn_objc_pointer_masking_performSelector;
}
S.Diag(OpLoc, Diag)
<< ObjCPointerExpr->getSourceRange();
}
}
static NamedDecl *getDeclFromExpr(Expr *E) {
if (!E)
return nullptr;
if (auto *DRE = dyn_cast<DeclRefExpr>(E))
return DRE->getDecl();
if (auto *ME = dyn_cast<MemberExpr>(E))
return ME->getMemberDecl();
if (auto *IRE = dyn_cast<ObjCIvarRefExpr>(E))
return IRE->getDecl();
return nullptr;
}
// This helper function promotes a binary operator's operands (which are of a
// half vector type) to a vector of floats and then truncates the result to
// a vector of either half or short.
static ExprResult convertHalfVecBinOp(Sema &S, ExprResult LHS, ExprResult RHS,
BinaryOperatorKind Opc, QualType ResultTy,
ExprValueKind VK, ExprObjectKind OK,
bool IsCompAssign, SourceLocation OpLoc,
FPOptions FPFeatures) {
auto &Context = S.getASTContext();
assert((isVector(ResultTy, Context.HalfTy) ||
isVector(ResultTy, Context.ShortTy)) &&
"Result must be a vector of half or short");
assert(isVector(LHS.get()->getType(), Context.HalfTy) &&
isVector(RHS.get()->getType(), Context.HalfTy) &&
"both operands expected to be a half vector");
RHS = convertVector(RHS.get(), Context.FloatTy, S);
QualType BinOpResTy = RHS.get()->getType();
// If Opc is a comparison, ResultType is a vector of shorts. In that case,
// change BinOpResTy to a vector of ints.
if (isVector(ResultTy, Context.ShortTy))
BinOpResTy = S.GetSignedVectorType(BinOpResTy);
if (IsCompAssign)
return new (Context) CompoundAssignOperator(
LHS.get(), RHS.get(), Opc, ResultTy, VK, OK, BinOpResTy, BinOpResTy,
OpLoc, FPFeatures);
LHS = convertVector(LHS.get(), Context.FloatTy, S);
auto *BO = new (Context) BinaryOperator(LHS.get(), RHS.get(), Opc, BinOpResTy,
VK, OK, OpLoc, FPFeatures);
return convertVector(BO, ResultTy->getAs<VectorType>()->getElementType(), S);
}
static std::pair<ExprResult, ExprResult>
CorrectDelayedTyposInBinOp(Sema &S, BinaryOperatorKind Opc, Expr *LHSExpr,
Expr *RHSExpr) {
ExprResult LHS = LHSExpr, RHS = RHSExpr;
if (!S.getLangOpts().CPlusPlus) {
// C cannot handle TypoExpr nodes on either side of a binop because it
// doesn't handle dependent types properly, so make sure any TypoExprs have
// been dealt with before checking the operands.
LHS = S.CorrectDelayedTyposInExpr(LHS);
RHS = S.CorrectDelayedTyposInExpr(RHS, [Opc, LHS](Expr *E) {
if (Opc != BO_Assign)
return ExprResult(E);
// Avoid correcting the RHS to the same Expr as the LHS.
Decl *D = getDeclFromExpr(E);
return (D && D == getDeclFromExpr(LHS.get())) ? ExprError() : E;
});
}
return std::make_pair(LHS, RHS);
}
/// Returns true if conversion between vectors of halfs and vectors of floats
/// is needed.
static bool needsConversionOfHalfVec(bool OpRequiresConversion, ASTContext &Ctx,
QualType SrcType) {
return OpRequiresConversion && !Ctx.getLangOpts().NativeHalfType &&
!Ctx.getTargetInfo().useFP16ConversionIntrinsics() &&
isVector(SrcType, Ctx.HalfTy);
}
/// CreateBuiltinBinOp - Creates a new built-in binary operation with
/// operator @p Opc at location @c TokLoc. This routine only supports
/// built-in operations; ActOnBinOp handles overloaded operators.
ExprResult Sema::CreateBuiltinBinOp(SourceLocation OpLoc,
BinaryOperatorKind Opc,
Expr *LHSExpr, Expr *RHSExpr) {
if (getLangOpts().CPlusPlus11 && isa<InitListExpr>(RHSExpr)) {
// The syntax only allows initializer lists on the RHS of assignment,
// so we don't need to worry about accepting invalid code for
// non-assignment operators.
// C++11 5.17p9:
// The meaning of x = {v} [...] is that of x = T(v) [...]. The meaning
// of x = {} is x = T().
InitializationKind Kind = InitializationKind::CreateDirectList(
RHSExpr->getLocStart(), RHSExpr->getLocStart(), RHSExpr->getLocEnd());
InitializedEntity Entity =
InitializedEntity::InitializeTemporary(LHSExpr->getType());
InitializationSequence InitSeq(*this, Entity, Kind, RHSExpr);
ExprResult Init = InitSeq.Perform(*this, Entity, Kind, RHSExpr);
if (Init.isInvalid())
return Init;
RHSExpr = Init.get();
}
ExprResult LHS = LHSExpr, RHS = RHSExpr;
QualType ResultTy; // Result type of the binary operator.
// The following two variables are used for compound assignment operators
QualType CompLHSTy; // Type of LHS after promotions for computation
QualType CompResultTy; // Type of computation result
ExprValueKind VK = VK_RValue;
ExprObjectKind OK = OK_Ordinary;
bool ConvertHalfVec = false;
std::tie(LHS, RHS) = CorrectDelayedTyposInBinOp(*this, Opc, LHSExpr, RHSExpr);
if (!LHS.isUsable() || !RHS.isUsable())
return ExprError();
if (getLangOpts().OpenCL) {
QualType LHSTy = LHSExpr->getType();
QualType RHSTy = RHSExpr->getType();
// OpenCLC v2.0 s6.13.11.1 allows atomic variables to be initialized by
// the ATOMIC_VAR_INIT macro.
if (LHSTy->isAtomicType() || RHSTy->isAtomicType()) {
SourceRange SR(LHSExpr->getLocStart(), RHSExpr->getLocEnd());
if (BO_Assign == Opc)
Diag(OpLoc, diag::err_opencl_atomic_init) << 0 << SR;
else
ResultTy = InvalidOperands(OpLoc, LHS, RHS);
return ExprError();
}
// OpenCL special types - image, sampler, pipe, and blocks are to be used
// only with a builtin functions and therefore should be disallowed here.
if (LHSTy->isImageType() || RHSTy->isImageType() ||
LHSTy->isSamplerT() || RHSTy->isSamplerT() ||
LHSTy->isPipeType() || RHSTy->isPipeType() ||
LHSTy->isBlockPointerType() || RHSTy->isBlockPointerType()) {
ResultTy = InvalidOperands(OpLoc, LHS, RHS);
return ExprError();
}
}
switch (Opc) {
case BO_Assign:
ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, QualType());
if (getLangOpts().CPlusPlus &&
LHS.get()->getObjectKind() != OK_ObjCProperty) {
VK = LHS.get()->getValueKind();
OK = LHS.get()->getObjectKind();
}
if (!ResultTy.isNull()) {
DiagnoseSelfAssignment(*this, LHS.get(), RHS.get(), OpLoc, true);
DiagnoseSelfMove(LHS.get(), RHS.get(), OpLoc);
}
RecordModifiableNonNullParam(*this, LHS.get());
break;
case BO_PtrMemD:
case BO_PtrMemI:
ResultTy = CheckPointerToMemberOperands(LHS, RHS, VK, OpLoc,
Opc == BO_PtrMemI);
break;
case BO_Mul:
case BO_Div:
ConvertHalfVec = true;
ResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, false,
Opc == BO_Div);
break;
case BO_Rem:
ResultTy = CheckRemainderOperands(LHS, RHS, OpLoc);
break;
case BO_Add:
ConvertHalfVec = true;
ResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc);
break;
case BO_Sub:
ConvertHalfVec = true;
ResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc);
break;
case BO_Shl:
case BO_Shr:
ResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc);
break;
case BO_LE:
case BO_LT:
case BO_GE:
case BO_GT:
ConvertHalfVec = true;
ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc);
break;
case BO_EQ:
case BO_NE:
ConvertHalfVec = true;
ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc);
break;
case BO_Cmp:
ConvertHalfVec = true;
ResultTy = CheckCompareOperands(LHS, RHS, OpLoc, Opc);
assert(ResultTy.isNull() || ResultTy->getAsCXXRecordDecl());
break;
case BO_And:
checkObjCPointerIntrospection(*this, LHS, RHS, OpLoc);
LLVM_FALLTHROUGH;
case BO_Xor:
case BO_Or:
ResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc, Opc);
break;
case BO_LAnd:
case BO_LOr:
ConvertHalfVec = true;
ResultTy = CheckLogicalOperands(LHS, RHS, OpLoc, Opc);
break;
case BO_MulAssign:
case BO_DivAssign:
ConvertHalfVec = true;
CompResultTy = CheckMultiplyDivideOperands(LHS, RHS, OpLoc, true,
Opc == BO_DivAssign);
CompLHSTy = CompResultTy;
if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
break;
case BO_RemAssign:
CompResultTy = CheckRemainderOperands(LHS, RHS, OpLoc, true);
CompLHSTy = CompResultTy;
if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
break;
case BO_AddAssign:
ConvertHalfVec = true;
CompResultTy = CheckAdditionOperands(LHS, RHS, OpLoc, Opc, &CompLHSTy);
if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
break;
case BO_SubAssign:
ConvertHalfVec = true;
CompResultTy = CheckSubtractionOperands(LHS, RHS, OpLoc, &CompLHSTy);
if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
break;
case BO_ShlAssign:
case BO_ShrAssign:
CompResultTy = CheckShiftOperands(LHS, RHS, OpLoc, Opc, true);
CompLHSTy = CompResultTy;
if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
break;
case BO_AndAssign:
case BO_OrAssign: // fallthrough
DiagnoseSelfAssignment(*this, LHS.get(), RHS.get(), OpLoc, true);
LLVM_FALLTHROUGH;
case BO_XorAssign:
CompResultTy = CheckBitwiseOperands(LHS, RHS, OpLoc, Opc);
CompLHSTy = CompResultTy;
if (!CompResultTy.isNull() && !LHS.isInvalid() && !RHS.isInvalid())
ResultTy = CheckAssignmentOperands(LHS.get(), RHS, OpLoc, CompResultTy);
break;
case BO_Comma:
ResultTy = CheckCommaOperands(*this, LHS, RHS, OpLoc);
if (getLangOpts().CPlusPlus && !RHS.isInvalid()) {
VK = RHS.get()->getValueKind();
OK = RHS.get()->getObjectKind();
}
break;
}
if (ResultTy.isNull() || LHS.isInvalid() || RHS.isInvalid())
return ExprError();
// Some of the binary operations require promoting operands of half vector to
// float vectors and truncating the result back to half vector. For now, we do
// this only when HalfArgsAndReturn is set (that is, when the target is arm or
// arm64).
assert(isVector(RHS.get()->getType(), Context.HalfTy) ==
isVector(LHS.get()->getType(), Context.HalfTy) &&
"both sides are half vectors or neither sides are");
ConvertHalfVec = needsConversionOfHalfVec(ConvertHalfVec, Context,
LHS.get()->getType());
// Check for array bounds violations for both sides of the BinaryOperator
CheckArrayAccess(LHS.get());
CheckArrayAccess(RHS.get());
if (const ObjCIsaExpr *OISA = dyn_cast<ObjCIsaExpr>(LHS.get()->IgnoreParenCasts())) {
NamedDecl *ObjectSetClass = LookupSingleName(TUScope,
&Context.Idents.get("object_setClass"),
SourceLocation(), LookupOrdinaryName);
if (ObjectSetClass && isa<ObjCIsaExpr>(LHS.get())) {
SourceLocation RHSLocEnd = getLocForEndOfToken(RHS.get()->getLocEnd());
Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign) <<
FixItHint::CreateInsertion(LHS.get()->getLocStart(), "object_setClass(") <<
FixItHint::CreateReplacement(SourceRange(OISA->getOpLoc(), OpLoc), ",") <<
FixItHint::CreateInsertion(RHSLocEnd, ")");
}
else
Diag(LHS.get()->getExprLoc(), diag::warn_objc_isa_assign);
}
else if (const ObjCIvarRefExpr *OIRE =
dyn_cast<ObjCIvarRefExpr>(LHS.get()->IgnoreParenCasts()))
DiagnoseDirectIsaAccess(*this, OIRE, OpLoc, RHS.get());
// Opc is not a compound assignment if CompResultTy is null.
if (CompResultTy.isNull()) {
if (ConvertHalfVec)
return convertHalfVecBinOp(*this, LHS, RHS, Opc, ResultTy, VK, OK, false,
OpLoc, FPFeatures);
return new (Context) BinaryOperator(LHS.get(), RHS.get(), Opc, ResultTy, VK,
OK, OpLoc, FPFeatures);
}
// Handle compound assignments.
if (getLangOpts().CPlusPlus && LHS.get()->getObjectKind() !=
OK_ObjCProperty) {
VK = VK_LValue;
OK = LHS.get()->getObjectKind();
}
if (ConvertHalfVec)
return convertHalfVecBinOp(*this, LHS, RHS, Opc, ResultTy, VK, OK, true,
OpLoc, FPFeatures);
return new (Context) CompoundAssignOperator(
LHS.get(), RHS.get(), Opc, ResultTy, VK, OK, CompLHSTy, CompResultTy,
OpLoc, FPFeatures);
}
/// DiagnoseBitwisePrecedence - Emit a warning when bitwise and comparison
/// operators are mixed in a way that suggests that the programmer forgot that
/// comparison operators have higher precedence. The most typical example of
/// such code is "flags & 0x0020 != 0", which is equivalent to "flags & 1".
static void DiagnoseBitwisePrecedence(Sema &Self, BinaryOperatorKind Opc,
SourceLocation OpLoc, Expr *LHSExpr,
Expr *RHSExpr) {
BinaryOperator *LHSBO = dyn_cast<BinaryOperator>(LHSExpr);
BinaryOperator *RHSBO = dyn_cast<BinaryOperator>(RHSExpr);
// Check that one of the sides is a comparison operator and the other isn't.
bool isLeftComp = LHSBO && LHSBO->isComparisonOp();
bool isRightComp = RHSBO && RHSBO->isComparisonOp();
if (isLeftComp == isRightComp)
return;
// Bitwise operations are sometimes used as eager logical ops.
// Don't diagnose this.
bool isLeftBitwise = LHSBO && LHSBO->isBitwiseOp();
bool isRightBitwise = RHSBO && RHSBO->isBitwiseOp();
if (isLeftBitwise || isRightBitwise)
return;
SourceRange DiagRange = isLeftComp ? SourceRange(LHSExpr->getLocStart(),
OpLoc)
: SourceRange(OpLoc, RHSExpr->getLocEnd());
StringRef OpStr = isLeftComp ? LHSBO->getOpcodeStr() : RHSBO->getOpcodeStr();
SourceRange ParensRange = isLeftComp ?
SourceRange(LHSBO->getRHS()->getLocStart(), RHSExpr->getLocEnd())
: SourceRange(LHSExpr->getLocStart(), RHSBO->getLHS()->getLocEnd());
Self.Diag(OpLoc, diag::warn_precedence_bitwise_rel)
<< DiagRange << BinaryOperator::getOpcodeStr(Opc) << OpStr;
SuggestParentheses(Self, OpLoc,
Self.PDiag(diag::note_precedence_silence) << OpStr,
(isLeftComp ? LHSExpr : RHSExpr)->getSourceRange());
SuggestParentheses(Self, OpLoc,
Self.PDiag(diag::note_precedence_bitwise_first)
<< BinaryOperator::getOpcodeStr(Opc),
ParensRange);
}
/// It accepts a '&&' expr that is inside a '||' one.
/// Emit a diagnostic together with a fixit hint that wraps the '&&' expression
/// in parentheses.
static void
EmitDiagnosticForLogicalAndInLogicalOr(Sema &Self, SourceLocation OpLoc,
BinaryOperator *Bop) {
assert(Bop->getOpcode() == BO_LAnd);
Self.Diag(Bop->getOperatorLoc(), diag::warn_logical_and_in_logical_or)
<< Bop->getSourceRange() << OpLoc;
SuggestParentheses(Self, Bop->getOperatorLoc(),
Self.PDiag(diag::note_precedence_silence)
<< Bop->getOpcodeStr(),
Bop->getSourceRange());
}
/// Returns true if the given expression can be evaluated as a constant
/// 'true'.
static bool EvaluatesAsTrue(Sema &S, Expr *E) {
bool Res;
return !E->isValueDependent() &&
E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && Res;
}
/// Returns true if the given expression can be evaluated as a constant
/// 'false'.
static bool EvaluatesAsFalse(Sema &S, Expr *E) {
bool Res;
return !E->isValueDependent() &&
E->EvaluateAsBooleanCondition(Res, S.getASTContext()) && !Res;
}
/// Look for '&&' in the left hand of a '||' expr.
static void DiagnoseLogicalAndInLogicalOrLHS(Sema &S, SourceLocation OpLoc,
Expr *LHSExpr, Expr *RHSExpr) {
if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(LHSExpr)) {
if (Bop->getOpcode() == BO_LAnd) {
// If it's "a && b || 0" don't warn since the precedence doesn't matter.
if (EvaluatesAsFalse(S, RHSExpr))
return;
// If it's "1 && a || b" don't warn since the precedence doesn't matter.
if (!EvaluatesAsTrue(S, Bop->getLHS()))
return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop);
} else if (Bop->getOpcode() == BO_LOr) {
if (BinaryOperator *RBop = dyn_cast<BinaryOperator>(Bop->getRHS())) {
// If it's "a || b && 1 || c" we didn't warn earlier for
// "a || b && 1", but warn now.
if (RBop->getOpcode() == BO_LAnd && EvaluatesAsTrue(S, RBop->getRHS()))
return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, RBop);
}
}
}
}
/// Look for '&&' in the right hand of a '||' expr.
static void DiagnoseLogicalAndInLogicalOrRHS(Sema &S, SourceLocation OpLoc,
Expr *LHSExpr, Expr *RHSExpr) {
if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(RHSExpr)) {
if (Bop->getOpcode() == BO_LAnd) {
// If it's "0 || a && b" don't warn since the precedence doesn't matter.
if (EvaluatesAsFalse(S, LHSExpr))
return;
// If it's "a || b && 1" don't warn since the precedence doesn't matter.
if (!EvaluatesAsTrue(S, Bop->getRHS()))
return EmitDiagnosticForLogicalAndInLogicalOr(S, OpLoc, Bop);
}
}
}
/// Look for bitwise op in the left or right hand of a bitwise op with
/// lower precedence and emit a diagnostic together with a fixit hint that wraps
/// the '&' expression in parentheses.
static void DiagnoseBitwiseOpInBitwiseOp(Sema &S, BinaryOperatorKind Opc,
SourceLocation OpLoc, Expr *SubExpr) {
if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(SubExpr)) {
if (Bop->isBitwiseOp() && Bop->getOpcode() < Opc) {
S.Diag(Bop->getOperatorLoc(), diag::warn_bitwise_op_in_bitwise_op)
<< Bop->getOpcodeStr() << BinaryOperator::getOpcodeStr(Opc)
<< Bop->getSourceRange() << OpLoc;
SuggestParentheses(S, Bop->getOperatorLoc(),
S.PDiag(diag::note_precedence_silence)
<< Bop->getOpcodeStr(),
Bop->getSourceRange());
}
}
}
static void DiagnoseAdditionInShift(Sema &S, SourceLocation OpLoc,
Expr *SubExpr, StringRef Shift) {
if (BinaryOperator *Bop = dyn_cast<BinaryOperator>(SubExpr)) {
if (Bop->getOpcode() == BO_Add || Bop->getOpcode() == BO_Sub) {
StringRef Op = Bop->getOpcodeStr();
S.Diag(Bop->getOperatorLoc(), diag::warn_addition_in_bitshift)
<< Bop->getSourceRange() << OpLoc << Shift << Op;
SuggestParentheses(S, Bop->getOperatorLoc(),
S.PDiag(diag::note_precedence_silence) << Op,
Bop->getSourceRange());
}
}
}
static void DiagnoseShiftCompare(Sema &S, SourceLocation OpLoc,
Expr *LHSExpr, Expr *RHSExpr) {
CXXOperatorCallExpr *OCE = dyn_cast<CXXOperatorCallExpr>(LHSExpr);
if (!OCE)
return;
FunctionDecl *FD = OCE->getDirectCallee();
if (!FD || !FD->isOverloadedOperator())
return;
OverloadedOperatorKind Kind = FD->getOverloadedOperator();
if (Kind != OO_LessLess && Kind != OO_GreaterGreater)
return;
S.Diag(OpLoc, diag::warn_overloaded_shift_in_comparison)
<< LHSExpr->getSourceRange() << RHSExpr->getSourceRange()
<< (Kind == OO_LessLess);
SuggestParentheses(S, OCE->getOperatorLoc(),
S.PDiag(diag::note_precedence_silence)
<< (Kind == OO_LessLess ? "<<" : ">>"),
OCE->getSourceRange());
SuggestParentheses(S, OpLoc,
S.PDiag(diag::note_evaluate_comparison_first),
SourceRange(OCE->getArg(1)->getLocStart(),
RHSExpr->getLocEnd()));
}
/// DiagnoseBinOpPrecedence - Emit warnings for expressions with tricky
/// precedence.
static void DiagnoseBinOpPrecedence(Sema &Self, BinaryOperatorKind Opc,
SourceLocation OpLoc, Expr *LHSExpr,
Expr *RHSExpr){
// Diagnose "arg1 'bitwise' arg2 'eq' arg3".
if (BinaryOperator::isBitwiseOp(Opc))
DiagnoseBitwisePrecedence(Self, Opc, OpLoc, LHSExpr, RHSExpr);
// Diagnose "arg1 & arg2 | arg3"
if ((Opc == BO_Or || Opc == BO_Xor) &&
!OpLoc.isMacroID()/* Don't warn in macros. */) {
DiagnoseBitwiseOpInBitwiseOp(Self, Opc, OpLoc, LHSExpr);
DiagnoseBitwiseOpInBitwiseOp(Self, Opc, OpLoc, RHSExpr);
}
// Warn about arg1 || arg2 && arg3, as GCC 4.3+ does.
// We don't warn for 'assert(a || b && "bad")' since this is safe.
if (Opc == BO_LOr && !OpLoc.isMacroID()/* Don't warn in macros. */) {
DiagnoseLogicalAndInLogicalOrLHS(Self, OpLoc, LHSExpr, RHSExpr);
DiagnoseLogicalAndInLogicalOrRHS(Self, OpLoc, LHSExpr, RHSExpr);
}
if ((Opc == BO_Shl && LHSExpr->getType()->isIntegralType(Self.getASTContext()))
|| Opc == BO_Shr) {
StringRef Shift = BinaryOperator::getOpcodeStr(Opc);
DiagnoseAdditionInShift(Self, OpLoc, LHSExpr, Shift);
DiagnoseAdditionInShift(Self, OpLoc, RHSExpr, Shift);
}
// Warn on overloaded shift operators and comparisons, such as:
// cout << 5 == 4;
if (BinaryOperator::isComparisonOp(Opc))
DiagnoseShiftCompare(Self, OpLoc, LHSExpr, RHSExpr);
}
// Binary Operators. 'Tok' is the token for the operator.
ExprResult Sema::ActOnBinOp(Scope *S, SourceLocation TokLoc,
tok::TokenKind Kind,
Expr *LHSExpr, Expr *RHSExpr) {
BinaryOperatorKind Opc = ConvertTokenKindToBinaryOpcode(Kind);
assert(LHSExpr && "ActOnBinOp(): missing left expression");
assert(RHSExpr && "ActOnBinOp(): missing right expression");
// Emit warnings for tricky precedence issues, e.g. "bitfield & 0x4 == 0"
DiagnoseBinOpPrecedence(*this, Opc, TokLoc, LHSExpr, RHSExpr);
return BuildBinOp(S, TokLoc, Opc, LHSExpr, RHSExpr);
}
/// Build an overloaded binary operator expression in the given scope.
static ExprResult BuildOverloadedBinOp(Sema &S, Scope *Sc, SourceLocation OpLoc,
BinaryOperatorKind Opc,
Expr *LHS, Expr *RHS) {
switch (Opc) {
case BO_Assign:
case BO_DivAssign:
case BO_RemAssign:
case BO_SubAssign:
case BO_AndAssign:
case BO_OrAssign:
case BO_XorAssign:
DiagnoseSelfAssignment(S, LHS, RHS, OpLoc, false);
CheckIdentityFieldAssignment(LHS, RHS, OpLoc, S);
break;
default:
break;
}
// Find all of the overloaded operators visible from this
// point. We perform both an operator-name lookup from the local
// scope and an argument-dependent lookup based on the types of
// the arguments.
UnresolvedSet<16> Functions;
OverloadedOperatorKind OverOp
= BinaryOperator::getOverloadedOperator(Opc);
if (Sc && OverOp != OO_None && OverOp != OO_Equal)
S.LookupOverloadedOperatorName(OverOp, Sc, LHS->getType(),
RHS->getType(), Functions);
// Build the (potentially-overloaded, potentially-dependent)
// binary operation.
return S.CreateOverloadedBinOp(OpLoc, Opc, Functions, LHS, RHS);
}
ExprResult Sema::BuildBinOp(Scope *S, SourceLocation OpLoc,
BinaryOperatorKind Opc,
Expr *LHSExpr, Expr *RHSExpr) {
ExprResult LHS, RHS;
std::tie(LHS, RHS) = CorrectDelayedTyposInBinOp(*this, Opc, LHSExpr, RHSExpr);
if (!LHS.isUsable() || !RHS.isUsable())
return ExprError();
LHSExpr = LHS.get();
RHSExpr = RHS.get();
// We want to end up calling one of checkPseudoObjectAssignment
// (if the LHS is a pseudo-object), BuildOverloadedBinOp (if
// both expressions are overloadable or either is type-dependent),
// or CreateBuiltinBinOp (in any other case). We also want to get
// any placeholder types out of the way.
// Handle pseudo-objects in the LHS.
if (const BuiltinType *pty = LHSExpr->getType()->getAsPlaceholderType()) {
// Assignments with a pseudo-object l-value need special analysis.
if (pty->getKind() == BuiltinType::PseudoObject &&
BinaryOperator::isAssignmentOp(Opc))
return checkPseudoObjectAssignment(S, OpLoc, Opc, LHSExpr, RHSExpr);
// Don't resolve overloads if the other type is overloadable.
if (getLangOpts().CPlusPlus && pty->getKind() == BuiltinType::Overload) {
// We can't actually test that if we still have a placeholder,
// though. Fortunately, none of the exceptions we see in that
// code below are valid when the LHS is an overload set. Note
// that an overload set can be dependently-typed, but it never
// instantiates to having an overloadable type.
ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr);
if (resolvedRHS.isInvalid()) return ExprError();
RHSExpr = resolvedRHS.get();
if (RHSExpr->isTypeDependent() ||
RHSExpr->getType()->isOverloadableType())
return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
}
// If we're instantiating "a.x < b" or "A::x < b" and 'x' names a function
// template, diagnose the missing 'template' keyword instead of diagnosing
// an invalid use of a bound member function.
//
// Note that "A::x < b" might be valid if 'b' has an overloadable type due
// to C++1z [over.over]/1.4, but we already checked for that case above.
if (Opc == BO_LT && inTemplateInstantiation() &&
(pty->getKind() == BuiltinType::BoundMember ||
pty->getKind() == BuiltinType::Overload)) {
auto *OE = dyn_cast<OverloadExpr>(LHSExpr);
if (OE && !OE->hasTemplateKeyword() && !OE->hasExplicitTemplateArgs() &&
std::any_of(OE->decls_begin(), OE->decls_end(), [](NamedDecl *ND) {
return isa<FunctionTemplateDecl>(ND);
})) {
Diag(OE->getQualifier() ? OE->getQualifierLoc().getBeginLoc()
: OE->getNameLoc(),
diag::err_template_kw_missing)
<< OE->getName().getAsString() << "";
return ExprError();
}
}
ExprResult LHS = CheckPlaceholderExpr(LHSExpr);
if (LHS.isInvalid()) return ExprError();
LHSExpr = LHS.get();
}
// Handle pseudo-objects in the RHS.
if (const BuiltinType *pty = RHSExpr->getType()->getAsPlaceholderType()) {
// An overload in the RHS can potentially be resolved by the type
// being assigned to.
if (Opc == BO_Assign && pty->getKind() == BuiltinType::Overload) {
if (getLangOpts().CPlusPlus &&
(LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent() ||
LHSExpr->getType()->isOverloadableType()))
return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr);
}
// Don't resolve overloads if the other type is overloadable.
if (getLangOpts().CPlusPlus && pty->getKind() == BuiltinType::Overload &&
LHSExpr->getType()->isOverloadableType())
return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
ExprResult resolvedRHS = CheckPlaceholderExpr(RHSExpr);
if (!resolvedRHS.isUsable()) return ExprError();
RHSExpr = resolvedRHS.get();
}
if (getLangOpts().CPlusPlus) {
// If either expression is type-dependent, always build an
// overloaded op.
if (LHSExpr->isTypeDependent() || RHSExpr->isTypeDependent())
return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
// Otherwise, build an overloaded op if either expression has an
// overloadable type.
if (LHSExpr->getType()->isOverloadableType() ||
RHSExpr->getType()->isOverloadableType())
return BuildOverloadedBinOp(*this, S, OpLoc, Opc, LHSExpr, RHSExpr);
}
// Build a built-in binary operation.
return CreateBuiltinBinOp(OpLoc, Opc, LHSExpr, RHSExpr);
}
static bool isOverflowingIntegerType(ASTContext &Ctx, QualType T) {
if (T.isNull() || T->isDependentType())
return false;
if (!T->isPromotableIntegerType())
return true;
return Ctx.getIntWidth(T) >= Ctx.getIntWidth(Ctx.IntTy);
}
ExprResult Sema::CreateBuiltinUnaryOp(SourceLocation OpLoc,
UnaryOperatorKind Opc,
Expr *InputExpr) {
ExprResult Input = InputExpr;
ExprValueKind VK = VK_RValue;
ExprObjectKind OK = OK_Ordinary;
QualType resultType;
bool CanOverflow = false;
bool ConvertHalfVec = false;
if (getLangOpts().OpenCL) {
QualType Ty = InputExpr->getType();
// The only legal unary operation for atomics is '&'.
if ((Opc != UO_AddrOf && Ty->isAtomicType()) ||
// OpenCL special types - image, sampler, pipe, and blocks are to be used
// only with a builtin functions and therefore should be disallowed here.
(Ty->isImageType() || Ty->isSamplerT() || Ty->isPipeType()
|| Ty->isBlockPointerType())) {
return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
<< InputExpr->getType()
<< Input.get()->getSourceRange());
}
}
switch (Opc) {
case UO_PreInc:
case UO_PreDec:
case UO_PostInc:
case UO_PostDec:
resultType = CheckIncrementDecrementOperand(*this, Input.get(), VK, OK,
OpLoc,
Opc == UO_PreInc ||
Opc == UO_PostInc,
Opc == UO_PreInc ||
Opc == UO_PreDec);
CanOverflow = isOverflowingIntegerType(Context, resultType);
break;
case UO_AddrOf:
resultType = CheckAddressOfOperand(Input, OpLoc);
RecordModifiableNonNullParam(*this, InputExpr);
break;
case UO_Deref: {
Input = DefaultFunctionArrayLvalueConversion(Input.get());
if (Input.isInvalid()) return ExprError();
resultType = CheckIndirectionOperand(*this, Input.get(), VK, OpLoc);
break;
}
case UO_Plus:
case UO_Minus:
CanOverflow = Opc == UO_Minus &&
isOverflowingIntegerType(Context, Input.get()->getType());
Input = UsualUnaryConversions(Input.get());
if (Input.isInvalid()) return ExprError();
// Unary plus and minus require promoting an operand of half vector to a
// float vector and truncating the result back to a half vector. For now, we
// do this only when HalfArgsAndReturns is set (that is, when the target is
// arm or arm64).
ConvertHalfVec =
needsConversionOfHalfVec(true, Context, Input.get()->getType());
// If the operand is a half vector, promote it to a float vector.
if (ConvertHalfVec)
Input = convertVector(Input.get(), Context.FloatTy, *this);
resultType = Input.get()->getType();
if (resultType->isDependentType())
break;
if (resultType->isArithmeticType()) // C99 6.5.3.3p1
break;
else if (resultType->isVectorType() &&
// The z vector extensions don't allow + or - with bool vectors.
(!Context.getLangOpts().ZVector ||
resultType->getAs<VectorType>()->getVectorKind() !=
VectorType::AltiVecBool))
break;
else if (getLangOpts().CPlusPlus && // C++ [expr.unary.op]p6
Opc == UO_Plus &&
resultType->isPointerType())
break;
return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
<< resultType << Input.get()->getSourceRange());
case UO_Not: // bitwise complement
Input = UsualUnaryConversions(Input.get());
if (Input.isInvalid())
return ExprError();
resultType = Input.get()->getType();
if (resultType->isDependentType())
break;
// C99 6.5.3.3p1. We allow complex int and float as a GCC extension.
if (resultType->isComplexType() || resultType->isComplexIntegerType())
// C99 does not support '~' for complex conjugation.
Diag(OpLoc, diag::ext_integer_complement_complex)
<< resultType << Input.get()->getSourceRange();
else if (resultType->hasIntegerRepresentation())
break;
else if (resultType->isExtVectorType() && Context.getLangOpts().OpenCL) {
// OpenCL v1.1 s6.3.f: The bitwise operator not (~) does not operate
// on vector float types.
QualType T = resultType->getAs<ExtVectorType>()->getElementType();
if (!T->isIntegerType())
return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
<< resultType << Input.get()->getSourceRange());
} else {
return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
<< resultType << Input.get()->getSourceRange());
}
break;
case UO_LNot: // logical negation
// Unlike +/-/~, integer promotions aren't done here (C99 6.5.3.3p5).
Input = DefaultFunctionArrayLvalueConversion(Input.get());
if (Input.isInvalid()) return ExprError();
resultType = Input.get()->getType();
// Though we still have to promote half FP to float...
if (resultType->isHalfType() && !Context.getLangOpts().NativeHalfType) {
Input = ImpCastExprToType(Input.get(), Context.FloatTy, CK_FloatingCast).get();
resultType = Context.FloatTy;
}
if (resultType->isDependentType())
break;
if (resultType->isScalarType() && !isScopedEnumerationType(resultType)) {
// C99 6.5.3.3p1: ok, fallthrough;
if (Context.getLangOpts().CPlusPlus) {
// C++03 [expr.unary.op]p8, C++0x [expr.unary.op]p9:
// operand contextually converted to bool.
Input = ImpCastExprToType(Input.get(), Context.BoolTy,
ScalarTypeToBooleanCastKind(resultType));
} else if (Context.getLangOpts().OpenCL &&
Context.getLangOpts().OpenCLVersion < 120) {
// OpenCL v1.1 6.3.h: The logical operator not (!) does not
// operate on scalar float types.
if (!resultType->isIntegerType() && !resultType->isPointerType())
return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
<< resultType << Input.get()->getSourceRange());
}
} else if (resultType->isExtVectorType()) {
if (Context.getLangOpts().OpenCL &&
Context.getLangOpts().OpenCLVersion < 120) {
// OpenCL v1.1 6.3.h: The logical operator not (!) does not
// operate on vector float types.
QualType T = resultType->getAs<ExtVectorType>()->getElementType();
if (!T->isIntegerType())
return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
<< resultType << Input.get()->getSourceRange());
}
// Vector logical not returns the signed variant of the operand type.
resultType = GetSignedVectorType(resultType);
break;
} else {
// FIXME: GCC's vector extension permits the usage of '!' with a vector
// type in C++. We should allow that here too.
return ExprError(Diag(OpLoc, diag::err_typecheck_unary_expr)
<< resultType << Input.get()->getSourceRange());
}
// LNot always has type int. C99 6.5.3.3p5.
// In C++, it's bool. C++ 5.3.1p8
resultType = Context.getLogicalOperationType();
break;
case UO_Real:
case UO_Imag:
resultType = CheckRealImagOperand(*this, Input, OpLoc, Opc == UO_Real);
// _Real maps ordinary l-values into ordinary l-values. _Imag maps ordinary
// complex l-values to ordinary l-values and all other values to r-values.
if (Input.isInvalid()) return ExprError();
if (Opc == UO_Real || Input.get()->getType()->isAnyComplexType()) {
if (Input.get()->getValueKind() != VK_RValue &&
Input.get()->getObjectKind() == OK_Ordinary)
VK = Input.get()->getValueKind();
} else if (!getLangOpts().CPlusPlus) {
// In C, a volatile scalar is read by __imag. In C++, it is not.
Input = DefaultLvalueConversion(Input.get());
}
break;
case UO_Extension:
resultType = Input.get()->getType();
VK = Input.get()->getValueKind();
OK = Input.get()->getObjectKind();
break;
case UO_Coawait:
// It's unnecessary to represent the pass-through operator co_await in the
// AST; just return the input expression instead.
assert(!Input.get()->getType()->isDependentType() &&
"the co_await expression must be non-dependant before "
"building operator co_await");
return Input;
}
if (resultType.isNull() || Input.isInvalid())
return ExprError();
// Check for array bounds violations in the operand of the UnaryOperator,
// except for the '*' and '&' operators that have to be handled specially
// by CheckArrayAccess (as there are special cases like &array[arraysize]
// that are explicitly defined as valid by the standard).
if (Opc != UO_AddrOf && Opc != UO_Deref)
CheckArrayAccess(Input.get());
auto *UO = new (Context)
UnaryOperator(Input.get(), Opc, resultType, VK, OK, OpLoc, CanOverflow);
// Convert the result back to a half vector.
if (ConvertHalfVec)
return convertVector(UO, Context.HalfTy, *this);
return UO;
}
/// Determine whether the given expression is a qualified member
/// access expression, of a form that could be turned into a pointer to member
/// with the address-of operator.
bool Sema::isQualifiedMemberAccess(Expr *E) {
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
if (!DRE->getQualifier())
return false;
ValueDecl *VD = DRE->getDecl();
if (!VD->isCXXClassMember())
return false;
if (isa<FieldDecl>(VD) || isa<IndirectFieldDecl>(VD))
return true;
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(VD))
return Method->isInstance();
return false;
}
if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) {
if (!ULE->getQualifier())
return false;
for (NamedDecl *D : ULE->decls()) {
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
if (Method->isInstance())
return true;
} else {
// Overload set does not contain methods.
break;
}
}
return false;
}
return false;
}
ExprResult Sema::BuildUnaryOp(Scope *S, SourceLocation OpLoc,
UnaryOperatorKind Opc, Expr *Input) {
// First things first: handle placeholders so that the
// overloaded-operator check considers the right type.
if (const BuiltinType *pty = Input->getType()->getAsPlaceholderType()) {
// Increment and decrement of pseudo-object references.
if (pty->getKind() == BuiltinType::PseudoObject &&
UnaryOperator::isIncrementDecrementOp(Opc))
return checkPseudoObjectIncDec(S, OpLoc, Opc, Input);
// extension is always a builtin operator.
if (Opc == UO_Extension)
return CreateBuiltinUnaryOp(OpLoc, Opc, Input);
// & gets special logic for several kinds of placeholder.
// The builtin code knows what to do.
if (Opc == UO_AddrOf &&
(pty->getKind() == BuiltinType::Overload ||
pty->getKind() == BuiltinType::UnknownAny ||
pty->getKind() == BuiltinType::BoundMember))
return CreateBuiltinUnaryOp(OpLoc, Opc, Input);
// Anything else needs to be handled now.
ExprResult Result = CheckPlaceholderExpr(Input);
if (Result.isInvalid()) return ExprError();
Input = Result.get();
}
if (getLangOpts().CPlusPlus && Input->getType()->isOverloadableType() &&
UnaryOperator::getOverloadedOperator(Opc) != OO_None &&
!(Opc == UO_AddrOf && isQualifiedMemberAccess(Input))) {
// Find all of the overloaded operators visible from this
// point. We perform both an operator-name lookup from the local
// scope and an argument-dependent lookup based on the types of
// the arguments.
UnresolvedSet<16> Functions;
OverloadedOperatorKind OverOp = UnaryOperator::getOverloadedOperator(Opc);
if (S && OverOp != OO_None)
LookupOverloadedOperatorName(OverOp, S, Input->getType(), QualType(),
Functions);
return CreateOverloadedUnaryOp(OpLoc, Opc, Functions, Input);
}
return CreateBuiltinUnaryOp(OpLoc, Opc, Input);
}
// Unary Operators. 'Tok' is the token for the operator.
ExprResult Sema::ActOnUnaryOp(Scope *S, SourceLocation OpLoc,
tok::TokenKind Op, Expr *Input) {
return BuildUnaryOp(S, OpLoc, ConvertTokenKindToUnaryOpcode(Op), Input);
}
/// ActOnAddrLabel - Parse the GNU address of label extension: "&&foo".
ExprResult Sema::ActOnAddrLabel(SourceLocation OpLoc, SourceLocation LabLoc,
LabelDecl *TheDecl) {
TheDecl->markUsed(Context);
// Create the AST node. The address of a label always has type 'void*'.
return new (Context) AddrLabelExpr(OpLoc, LabLoc, TheDecl,
Context.getPointerType(Context.VoidTy));
}
/// Given the last statement in a statement-expression, check whether
/// the result is a producing expression (like a call to an
/// ns_returns_retained function) and, if so, rebuild it to hoist the
/// release out of the full-expression. Otherwise, return null.
/// Cannot fail.
static Expr *maybeRebuildARCConsumingStmt(Stmt *Statement) {
// Should always be wrapped with one of these.
ExprWithCleanups *cleanups = dyn_cast<ExprWithCleanups>(Statement);
if (!cleanups) return nullptr;
ImplicitCastExpr *cast = dyn_cast<ImplicitCastExpr>(cleanups->getSubExpr());
if (!cast || cast->getCastKind() != CK_ARCConsumeObject)
return nullptr;
// Splice out the cast. This shouldn't modify any interesting
// features of the statement.
Expr *producer = cast->getSubExpr();
assert(producer->getType() == cast->getType());
assert(producer->getValueKind() == cast->getValueKind());
cleanups->setSubExpr(producer);
return cleanups;
}
void Sema::ActOnStartStmtExpr() {
PushExpressionEvaluationContext(ExprEvalContexts.back().Context);
}
void Sema::ActOnStmtExprError() {
// Note that function is also called by TreeTransform when leaving a
// StmtExpr scope without rebuilding anything.
DiscardCleanupsInEvaluationContext();
PopExpressionEvaluationContext();
}
ExprResult
Sema::ActOnStmtExpr(SourceLocation LPLoc, Stmt *SubStmt,
SourceLocation RPLoc) { // "({..})"
assert(SubStmt && isa<CompoundStmt>(SubStmt) && "Invalid action invocation!");
CompoundStmt *Compound = cast<CompoundStmt>(SubStmt);
if (hasAnyUnrecoverableErrorsInThisFunction())
DiscardCleanupsInEvaluationContext();
assert(!Cleanup.exprNeedsCleanups() &&
"cleanups within StmtExpr not correctly bound!");
PopExpressionEvaluationContext();
// FIXME: there are a variety of strange constraints to enforce here, for
// example, it is not possible to goto into a stmt expression apparently.
// More semantic analysis is needed.
// If there are sub-stmts in the compound stmt, take the type of the last one
// as the type of the stmtexpr.
QualType Ty = Context.VoidTy;
bool StmtExprMayBindToTemp = false;
if (!Compound->body_empty()) {
Stmt *LastStmt = Compound->body_back();
LabelStmt *LastLabelStmt = nullptr;
// If LastStmt is a label, skip down through into the body.
while (LabelStmt *Label = dyn_cast<LabelStmt>(LastStmt)) {
LastLabelStmt = Label;
LastStmt = Label->getSubStmt();
}
if (Expr *LastE = dyn_cast<Expr>(LastStmt)) {
// Do function/array conversion on the last expression, but not
// lvalue-to-rvalue. However, initialize an unqualified type.
ExprResult LastExpr = DefaultFunctionArrayConversion(LastE);
if (LastExpr.isInvalid())
return ExprError();
Ty = LastExpr.get()->getType().getUnqualifiedType();
if (!Ty->isDependentType() && !LastExpr.get()->isTypeDependent()) {
// In ARC, if the final expression ends in a consume, splice
// the consume out and bind it later. In the alternate case
// (when dealing with a retainable type), the result
// initialization will create a produce. In both cases the
// result will be +1, and we'll need to balance that out with
// a bind.
if (Expr *rebuiltLastStmt
= maybeRebuildARCConsumingStmt(LastExpr.get())) {
LastExpr = rebuiltLastStmt;
} else {
LastExpr = PerformCopyInitialization(
InitializedEntity::InitializeStmtExprResult(LPLoc, Ty),
SourceLocation(), LastExpr);
}
if (LastExpr.isInvalid())
return ExprError();
if (LastExpr.get() != nullptr) {
if (!LastLabelStmt)
Compound->setLastStmt(LastExpr.get());
else
LastLabelStmt->setSubStmt(LastExpr.get());
StmtExprMayBindToTemp = true;
}
}
}
}
// FIXME: Check that expression type is complete/non-abstract; statement
// expressions are not lvalues.
Expr *ResStmtExpr = new (Context) StmtExpr(Compound, Ty, LPLoc, RPLoc);
if (StmtExprMayBindToTemp)
return MaybeBindToTemporary(ResStmtExpr);
return ResStmtExpr;
}
ExprResult Sema::BuildBuiltinOffsetOf(SourceLocation BuiltinLoc,
TypeSourceInfo *TInfo,
ArrayRef<OffsetOfComponent> Components,
SourceLocation RParenLoc) {
QualType ArgTy = TInfo->getType();
bool Dependent = ArgTy->isDependentType();
SourceRange TypeRange = TInfo->getTypeLoc().getLocalSourceRange();
// We must have at least one component that refers to the type, and the first
// one is known to be a field designator. Verify that the ArgTy represents
// a struct/union/class.
if (!Dependent && !ArgTy->isRecordType())
return ExprError(Diag(BuiltinLoc, diag::err_offsetof_record_type)
<< ArgTy << TypeRange);
// Type must be complete per C99 7.17p3 because a declaring a variable
// with an incomplete type would be ill-formed.
if (!Dependent
&& RequireCompleteType(BuiltinLoc, ArgTy,
diag::err_offsetof_incomplete_type, TypeRange))
return ExprError();
bool DidWarnAboutNonPOD = false;
QualType CurrentType = ArgTy;
SmallVector<OffsetOfNode, 4> Comps;
SmallVector<Expr*, 4> Exprs;
for (const OffsetOfComponent &OC : Components) {
if (OC.isBrackets) {
// Offset of an array sub-field. TODO: Should we allow vector elements?
if (!CurrentType->isDependentType()) {
const ArrayType *AT = Context.getAsArrayType(CurrentType);
if(!AT)
return ExprError(Diag(OC.LocEnd, diag::err_offsetof_array_type)
<< CurrentType);
CurrentType = AT->getElementType();
} else
CurrentType = Context.DependentTy;
ExprResult IdxRval = DefaultLvalueConversion(static_cast<Expr*>(OC.U.E));
if (IdxRval.isInvalid())
return ExprError();
Expr *Idx = IdxRval.get();
// The expression must be an integral expression.
// FIXME: An integral constant expression?
if (!Idx->isTypeDependent() && !Idx->isValueDependent() &&
!Idx->getType()->isIntegerType())
return ExprError(Diag(Idx->getLocStart(),
diag::err_typecheck_subscript_not_integer)
<< Idx->getSourceRange());
// Record this array index.
Comps.push_back(OffsetOfNode(OC.LocStart, Exprs.size(), OC.LocEnd));
Exprs.push_back(Idx);
continue;
}
// Offset of a field.
if (CurrentType->isDependentType()) {
// We have the offset of a field, but we can't look into the dependent
// type. Just record the identifier of the field.
Comps.push_back(OffsetOfNode(OC.LocStart, OC.U.IdentInfo, OC.LocEnd));
CurrentType = Context.DependentTy;
continue;
}
// We need to have a complete type to look into.
if (RequireCompleteType(OC.LocStart, CurrentType,
diag::err_offsetof_incomplete_type))
return ExprError();
// Look for the designated field.
const RecordType *RC = CurrentType->getAs<RecordType>();
if (!RC)
return ExprError(Diag(OC.LocEnd, diag::err_offsetof_record_type)
<< CurrentType);
RecordDecl *RD = RC->getDecl();
// C++ [lib.support.types]p5:
// The macro offsetof accepts a restricted set of type arguments in this
// International Standard. type shall be a POD structure or a POD union
// (clause 9).
// C++11 [support.types]p4:
// If type is not a standard-layout class (Clause 9), the results are
// undefined.
if (CXXRecordDecl *CRD = dyn_cast<CXXRecordDecl>(RD)) {
bool IsSafe = LangOpts.CPlusPlus11? CRD->isStandardLayout() : CRD->isPOD();
unsigned DiagID =
LangOpts.CPlusPlus11? diag::ext_offsetof_non_standardlayout_type
: diag::ext_offsetof_non_pod_type;
if (!IsSafe && !DidWarnAboutNonPOD &&
DiagRuntimeBehavior(BuiltinLoc, nullptr,
PDiag(DiagID)
<< SourceRange(Components[0].LocStart, OC.LocEnd)
<< CurrentType))
DidWarnAboutNonPOD = true;
}
// Look for the field.
LookupResult R(*this, OC.U.IdentInfo, OC.LocStart, LookupMemberName);
LookupQualifiedName(R, RD);
FieldDecl *MemberDecl = R.getAsSingle<FieldDecl>();
IndirectFieldDecl *IndirectMemberDecl = nullptr;
if (!MemberDecl) {
if ((IndirectMemberDecl = R.getAsSingle<IndirectFieldDecl>()))
MemberDecl = IndirectMemberDecl->getAnonField();
}
if (!MemberDecl)
return ExprError(Diag(BuiltinLoc, diag::err_no_member)
<< OC.U.IdentInfo << RD << SourceRange(OC.LocStart,
OC.LocEnd));
// C99 7.17p3:
// (If the specified member is a bit-field, the behavior is undefined.)
//
// We diagnose this as an error.
if (MemberDecl->isBitField()) {
Diag(OC.LocEnd, diag::err_offsetof_bitfield)
<< MemberDecl->getDeclName()
<< SourceRange(BuiltinLoc, RParenLoc);
Diag(MemberDecl->getLocation(), diag::note_bitfield_decl);
return ExprError();
}
RecordDecl *Parent = MemberDecl->getParent();
if (IndirectMemberDecl)
Parent = cast<RecordDecl>(IndirectMemberDecl->getDeclContext());
// If the member was found in a base class, introduce OffsetOfNodes for
// the base class indirections.
CXXBasePaths Paths;
if (IsDerivedFrom(OC.LocStart, CurrentType, Context.getTypeDeclType(Parent),
Paths)) {
if (Paths.getDetectedVirtual()) {
Diag(OC.LocEnd, diag::err_offsetof_field_of_virtual_base)
<< MemberDecl->getDeclName()
<< SourceRange(BuiltinLoc, RParenLoc);
return ExprError();
}
CXXBasePath &Path = Paths.front();
for (const CXXBasePathElement &B : Path)
Comps.push_back(OffsetOfNode(B.Base));
}
if (IndirectMemberDecl) {
for (auto *FI : IndirectMemberDecl->chain()) {
assert(isa<FieldDecl>(FI));
Comps.push_back(OffsetOfNode(OC.LocStart,
cast<FieldDecl>(FI), OC.LocEnd));
}
} else
Comps.push_back(OffsetOfNode(OC.LocStart, MemberDecl, OC.LocEnd));
CurrentType = MemberDecl->getType().getNonReferenceType();
}
return OffsetOfExpr::Create(Context, Context.getSizeType(), BuiltinLoc, TInfo,
Comps, Exprs, RParenLoc);
}
ExprResult Sema::ActOnBuiltinOffsetOf(Scope *S,
SourceLocation BuiltinLoc,
SourceLocation TypeLoc,
ParsedType ParsedArgTy,
ArrayRef<OffsetOfComponent> Components,
SourceLocation RParenLoc) {
TypeSourceInfo *ArgTInfo;
QualType ArgTy = GetTypeFromParser(ParsedArgTy, &ArgTInfo);
if (ArgTy.isNull())
return ExprError();
if (!ArgTInfo)
ArgTInfo = Context.getTrivialTypeSourceInfo(ArgTy, TypeLoc);
return BuildBuiltinOffsetOf(BuiltinLoc, ArgTInfo, Components, RParenLoc);
}
ExprResult Sema::ActOnChooseExpr(SourceLocation BuiltinLoc,
Expr *CondExpr,
Expr *LHSExpr, Expr *RHSExpr,
SourceLocation RPLoc) {
assert((CondExpr && LHSExpr && RHSExpr) && "Missing type argument(s)");
ExprValueKind VK = VK_RValue;
ExprObjectKind OK = OK_Ordinary;
QualType resType;
bool ValueDependent = false;
bool CondIsTrue = false;
if (CondExpr->isTypeDependent() || CondExpr->isValueDependent()) {
resType = Context.DependentTy;
ValueDependent = true;
} else {
// The conditional expression is required to be a constant expression.
llvm::APSInt condEval(32);
ExprResult CondICE
= VerifyIntegerConstantExpression(CondExpr, &condEval,
diag::err_typecheck_choose_expr_requires_constant, false);
if (CondICE.isInvalid())
return ExprError();
CondExpr = CondICE.get();
CondIsTrue = condEval.getZExtValue();
// If the condition is > zero, then the AST type is the same as the LHSExpr.
Expr *ActiveExpr = CondIsTrue ? LHSExpr : RHSExpr;
resType = ActiveExpr->getType();
ValueDependent = ActiveExpr->isValueDependent();
VK = ActiveExpr->getValueKind();
OK = ActiveExpr->getObjectKind();
}
return new (Context)
ChooseExpr(BuiltinLoc, CondExpr, LHSExpr, RHSExpr, resType, VK, OK, RPLoc,
CondIsTrue, resType->isDependentType(), ValueDependent);
}
//===----------------------------------------------------------------------===//
// Clang Extensions.
//===----------------------------------------------------------------------===//
/// ActOnBlockStart - This callback is invoked when a block literal is started.
void Sema::ActOnBlockStart(SourceLocation CaretLoc, Scope *CurScope) {
BlockDecl *Block = BlockDecl::Create(Context, CurContext, CaretLoc);
if (LangOpts.CPlusPlus) {
Decl *ManglingContextDecl;
if (MangleNumberingContext *MCtx =
getCurrentMangleNumberContext(Block->getDeclContext(),
ManglingContextDecl)) {
unsigned ManglingNumber = MCtx->getManglingNumber(Block);
Block->setBlockMangling(ManglingNumber, ManglingContextDecl);
}
}
PushBlockScope(CurScope, Block);
CurContext->addDecl(Block);
if (CurScope)
PushDeclContext(CurScope, Block);
else
CurContext = Block;
getCurBlock()->HasImplicitReturnType = true;
// Enter a new evaluation context to insulate the block from any
// cleanups from the enclosing full-expression.
PushExpressionEvaluationContext(
ExpressionEvaluationContext::PotentiallyEvaluated);
}
void Sema::ActOnBlockArguments(SourceLocation CaretLoc, Declarator &ParamInfo,
Scope *CurScope) {
assert(ParamInfo.getIdentifier() == nullptr &&
"block-id should have no identifier!");
assert(ParamInfo.getContext() == DeclaratorContext::BlockLiteralContext);
BlockScopeInfo *CurBlock = getCurBlock();
TypeSourceInfo *Sig = GetTypeForDeclarator(ParamInfo, CurScope);
QualType T = Sig->getType();
// FIXME: We should allow unexpanded parameter packs here, but that would,
// in turn, make the block expression contain unexpanded parameter packs.
if (DiagnoseUnexpandedParameterPack(CaretLoc, Sig, UPPC_Block)) {
// Drop the parameters.
FunctionProtoType::ExtProtoInfo EPI;
EPI.HasTrailingReturn = false;
EPI.TypeQuals |= DeclSpec::TQ_const;
T = Context.getFunctionType(Context.DependentTy, None, EPI);
Sig = Context.getTrivialTypeSourceInfo(T);
}
// GetTypeForDeclarator always produces a function type for a block
// literal signature. Furthermore, it is always a FunctionProtoType
// unless the function was written with a typedef.
assert(T->isFunctionType() &&
"GetTypeForDeclarator made a non-function block signature");
// Look for an explicit signature in that function type.
FunctionProtoTypeLoc ExplicitSignature;
if ((ExplicitSignature =
Sig->getTypeLoc().getAsAdjusted<FunctionProtoTypeLoc>())) {
// Check whether that explicit signature was synthesized by
// GetTypeForDeclarator. If so, don't save that as part of the
// written signature.
if (ExplicitSignature.getLocalRangeBegin() ==
ExplicitSignature.getLocalRangeEnd()) {
// This would be much cheaper if we stored TypeLocs instead of
// TypeSourceInfos.
TypeLoc Result = ExplicitSignature.getReturnLoc();
unsigned Size = Result.getFullDataSize();
Sig = Context.CreateTypeSourceInfo(Result.getType(), Size);
Sig->getTypeLoc().initializeFullCopy(Result, Size);
ExplicitSignature = FunctionProtoTypeLoc();
}
}
CurBlock->TheDecl->setSignatureAsWritten(Sig);
CurBlock->FunctionType = T;
const FunctionType *Fn = T->getAs<FunctionType>();
QualType RetTy = Fn->getReturnType();
bool isVariadic =
(isa<FunctionProtoType>(Fn) && cast<FunctionProtoType>(Fn)->isVariadic());
CurBlock->TheDecl->setIsVariadic(isVariadic);
// Context.DependentTy is used as a placeholder for a missing block
// return type. TODO: what should we do with declarators like:
// ^ * { ... }
// If the answer is "apply template argument deduction"....
if (RetTy != Context.DependentTy) {
CurBlock->ReturnType = RetTy;
CurBlock->TheDecl->setBlockMissingReturnType(false);
CurBlock->HasImplicitReturnType = false;
}
// Push block parameters from the declarator if we had them.
SmallVector<ParmVarDecl*, 8> Params;
if (ExplicitSignature) {
for (unsigned I = 0, E = ExplicitSignature.getNumParams(); I != E; ++I) {
ParmVarDecl *Param = ExplicitSignature.getParam(I);
if (Param->getIdentifier() == nullptr &&
!Param->isImplicit() &&
!Param->isInvalidDecl() &&
!getLangOpts().CPlusPlus)
Diag(Param->getLocation(), diag::err_parameter_name_omitted);
Params.push_back(Param);
}
// Fake up parameter variables if we have a typedef, like
// ^ fntype { ... }
} else if (const FunctionProtoType *Fn = T->getAs<FunctionProtoType>()) {
for (const auto &I : Fn->param_types()) {
ParmVarDecl *Param = BuildParmVarDeclForTypedef(
CurBlock->TheDecl, ParamInfo.getLocStart(), I);
Params.push_back(Param);
}
}
// Set the parameters on the block decl.
if (!Params.empty()) {
CurBlock->TheDecl->setParams(Params);
CheckParmsForFunctionDef(CurBlock->TheDecl->parameters(),
/*CheckParameterNames=*/false);
}
// Finally we can process decl attributes.
ProcessDeclAttributes(CurScope, CurBlock->TheDecl, ParamInfo);
// Put the parameter variables in scope.
for (auto AI : CurBlock->TheDecl->parameters()) {
AI->setOwningFunction(CurBlock->TheDecl);
// If this has an identifier, add it to the scope stack.
if (AI->getIdentifier()) {
CheckShadow(CurBlock->TheScope, AI);
PushOnScopeChains(AI, CurBlock->TheScope);
}
}
}
/// ActOnBlockError - If there is an error parsing a block, this callback
/// is invoked to pop the information about the block from the action impl.
void Sema::ActOnBlockError(SourceLocation CaretLoc, Scope *CurScope) {
// Leave the expression-evaluation context.
DiscardCleanupsInEvaluationContext();
PopExpressionEvaluationContext();
// Pop off CurBlock, handle nested blocks.
PopDeclContext();
PopFunctionScopeInfo();
}
/// ActOnBlockStmtExpr - This is called when the body of a block statement
/// literal was successfully completed. ^(int x){...}
ExprResult Sema::ActOnBlockStmtExpr(SourceLocation CaretLoc,
Stmt *Body, Scope *CurScope) {
// If blocks are disabled, emit an error.
if (!LangOpts.Blocks)
Diag(CaretLoc, diag::err_blocks_disable) << LangOpts.OpenCL;
// Leave the expression-evaluation context.
if (hasAnyUnrecoverableErrorsInThisFunction())
DiscardCleanupsInEvaluationContext();
assert(!Cleanup.exprNeedsCleanups() &&
"cleanups within block not correctly bound!");
PopExpressionEvaluationContext();
BlockScopeInfo *BSI = cast<BlockScopeInfo>(FunctionScopes.back());
if (BSI->HasImplicitReturnType)
deduceClosureReturnType(*BSI);
PopDeclContext();
QualType RetTy = Context.VoidTy;
if (!BSI->ReturnType.isNull())
RetTy = BSI->ReturnType;
bool NoReturn = BSI->TheDecl->hasAttr<NoReturnAttr>();
QualType BlockTy;
// Set the captured variables on the block.
// FIXME: Share capture structure between BlockDecl and CapturingScopeInfo!
SmallVector<BlockDecl::Capture, 4> Captures;
for (Capture &Cap : BSI->Captures) {
if (Cap.isThisCapture())
continue;
BlockDecl::Capture NewCap(Cap.getVariable(), Cap.isBlockCapture(),
Cap.isNested(), Cap.getInitExpr());
Captures.push_back(NewCap);
}
BSI->TheDecl->setCaptures(Context, Captures, BSI->CXXThisCaptureIndex != 0);
// If the user wrote a function type in some form, try to use that.
if (!BSI->FunctionType.isNull()) {
const FunctionType *FTy = BSI->FunctionType->getAs<FunctionType>();
FunctionType::ExtInfo Ext = FTy->getExtInfo();
if (NoReturn && !Ext.getNoReturn()) Ext = Ext.withNoReturn(true);
// Turn protoless block types into nullary block types.
if (isa<FunctionNoProtoType>(FTy)) {
FunctionProtoType::ExtProtoInfo EPI;
EPI.ExtInfo = Ext;
BlockTy = Context.getFunctionType(RetTy, None, EPI);
// Otherwise, if we don't need to change anything about the function type,
// preserve its sugar structure.
} else if (FTy->getReturnType() == RetTy &&
(!NoReturn || FTy->getNoReturnAttr())) {
BlockTy = BSI->FunctionType;
// Otherwise, make the minimal modifications to the function type.
} else {
const FunctionProtoType *FPT = cast<FunctionProtoType>(FTy);
FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
EPI.TypeQuals = 0; // FIXME: silently?
EPI.ExtInfo = Ext;
BlockTy = Context.getFunctionType(RetTy, FPT->getParamTypes(), EPI);
}
// If we don't have a function type, just build one from nothing.
} else {
FunctionProtoType::ExtProtoInfo EPI;
EPI.ExtInfo = FunctionType::ExtInfo().withNoReturn(NoReturn);
BlockTy = Context.getFunctionType(RetTy, None, EPI);
}
DiagnoseUnusedParameters(BSI->TheDecl->parameters());
BlockTy = Context.getBlockPointerType(BlockTy);
// If needed, diagnose invalid gotos and switches in the block.
if (getCurFunction()->NeedsScopeChecking() &&
!PP.isCodeCompletionEnabled())
DiagnoseInvalidJumps(cast<CompoundStmt>(Body));
BSI->TheDecl->setBody(cast<CompoundStmt>(Body));
if (Body && getCurFunction()->HasPotentialAvailabilityViolations)
DiagnoseUnguardedAvailabilityViolations(BSI->TheDecl);
// Try to apply the named return value optimization. We have to check again
// if we can do this, though, because blocks keep return statements around
// to deduce an implicit return type.
if (getLangOpts().CPlusPlus && RetTy->isRecordType() &&
!BSI->TheDecl->isDependentContext())
computeNRVO(Body, BSI);
BlockExpr *Result = new (Context) BlockExpr(BSI->TheDecl, BlockTy);
AnalysisBasedWarnings::Policy WP = AnalysisWarnings.getDefaultPolicy();
PopFunctionScopeInfo(&WP, Result->getBlockDecl(), Result);
// If the block isn't obviously global, i.e. it captures anything at
// all, then we need to do a few things in the surrounding context:
if (Result->getBlockDecl()->hasCaptures()) {
// First, this expression has a new cleanup object.
ExprCleanupObjects.push_back(Result->getBlockDecl());
Cleanup.setExprNeedsCleanups(true);
// It also gets a branch-protected scope if any of the captured
// variables needs destruction.
for (const auto &CI : Result->getBlockDecl()->captures()) {
const VarDecl *var = CI.getVariable();
if (var->getType().isDestructedType() != QualType::DK_none) {
setFunctionHasBranchProtectedScope();
break;
}
}
}
return Result;
}
ExprResult Sema::ActOnVAArg(SourceLocation BuiltinLoc, Expr *E, ParsedType Ty,
SourceLocation RPLoc) {
TypeSourceInfo *TInfo;
GetTypeFromParser(Ty, &TInfo);
return BuildVAArgExpr(BuiltinLoc, E, TInfo, RPLoc);
}
ExprResult Sema::BuildVAArgExpr(SourceLocation BuiltinLoc,
Expr *E, TypeSourceInfo *TInfo,
SourceLocation RPLoc) {
Expr *OrigExpr = E;
bool IsMS = false;
// CUDA device code does not support varargs.
if (getLangOpts().CUDA && getLangOpts().CUDAIsDevice) {
if (const FunctionDecl *F = dyn_cast<FunctionDecl>(CurContext)) {
CUDAFunctionTarget T = IdentifyCUDATarget(F);
if (T == CFT_Global || T == CFT_Device || T == CFT_HostDevice)
return ExprError(Diag(E->getLocStart(), diag::err_va_arg_in_device));
}
}
// It might be a __builtin_ms_va_list. (But don't ever mark a va_arg()
// as Microsoft ABI on an actual Microsoft platform, where
// __builtin_ms_va_list and __builtin_va_list are the same.)
if (!E->isTypeDependent() && Context.getTargetInfo().hasBuiltinMSVaList() &&
Context.getTargetInfo().getBuiltinVaListKind() != TargetInfo::CharPtrBuiltinVaList) {
QualType MSVaListType = Context.getBuiltinMSVaListType();
if (Context.hasSameType(MSVaListType, E->getType())) {
if (CheckForModifiableLvalue(E, BuiltinLoc, *this))
return ExprError();
IsMS = true;
}
}
// Get the va_list type
QualType VaListType = Context.getBuiltinVaListType();
if (!IsMS) {
if (VaListType->isArrayType()) {
// Deal with implicit array decay; for example, on x86-64,
// va_list is an array, but it's supposed to decay to
// a pointer for va_arg.
VaListType = Context.getArrayDecayedType(VaListType);
// Make sure the input expression also decays appropriately.
ExprResult Result = UsualUnaryConversions(E);
if (Result.isInvalid())
return ExprError();
E = Result.get();
} else if (VaListType->isRecordType() && getLangOpts().CPlusPlus) {
// If va_list is a record type and we are compiling in C++ mode,
// check the argument using reference binding.
InitializedEntity Entity = InitializedEntity::InitializeParameter(
Context, Context.getLValueReferenceType(VaListType), false);
ExprResult Init = PerformCopyInitialization(Entity, SourceLocation(), E);
if (Init.isInvalid())
return ExprError();
E = Init.getAs<Expr>();
} else {
// Otherwise, the va_list argument must be an l-value because
// it is modified by va_arg.
if (!E->isTypeDependent() &&
CheckForModifiableLvalue(E, BuiltinLoc, *this))
return ExprError();
}
}
if (!IsMS && !E->isTypeDependent() &&
!Context.hasSameType(VaListType, E->getType()))
return ExprError(Diag(E->getLocStart(),
diag::err_first_argument_to_va_arg_not_of_type_va_list)
<< OrigExpr->getType() << E->getSourceRange());
if (!TInfo->getType()->isDependentType()) {
if (RequireCompleteType(TInfo->getTypeLoc().getBeginLoc(), TInfo->getType(),
diag::err_second_parameter_to_va_arg_incomplete,
TInfo->getTypeLoc()))
return ExprError();
if (RequireNonAbstractType(TInfo->getTypeLoc().getBeginLoc(),
TInfo->getType(),
diag::err_second_parameter_to_va_arg_abstract,
TInfo->getTypeLoc()))
return ExprError();
if (!TInfo->getType().isPODType(Context)) {
Diag(TInfo->getTypeLoc().getBeginLoc(),
TInfo->getType()->isObjCLifetimeType()
? diag::warn_second_parameter_to_va_arg_ownership_qualified
: diag::warn_second_parameter_to_va_arg_not_pod)
<< TInfo->getType()
<< TInfo->getTypeLoc().getSourceRange();
}
// Check for va_arg where arguments of the given type will be promoted
// (i.e. this va_arg is guaranteed to have undefined behavior).
QualType PromoteType;
if (TInfo->getType()->isPromotableIntegerType()) {
PromoteType = Context.getPromotedIntegerType(TInfo->getType());
if (Context.typesAreCompatible(PromoteType, TInfo->getType()))
PromoteType = QualType();
}
if (TInfo->getType()->isSpecificBuiltinType(BuiltinType::Float))
PromoteType = Context.DoubleTy;
if (!PromoteType.isNull())
DiagRuntimeBehavior(TInfo->getTypeLoc().getBeginLoc(), E,
PDiag(diag::warn_second_parameter_to_va_arg_never_compatible)
<< TInfo->getType()
<< PromoteType
<< TInfo->getTypeLoc().getSourceRange());
}
QualType T = TInfo->getType().getNonLValueExprType(Context);
return new (Context) VAArgExpr(BuiltinLoc, E, TInfo, RPLoc, T, IsMS);
}
ExprResult Sema::ActOnGNUNullExpr(SourceLocation TokenLoc) {
// The type of __null will be int or long, depending on the size of
// pointers on the target.
QualType Ty;
unsigned pw = Context.getTargetInfo().getPointerWidth(0);
if (pw == Context.getTargetInfo().getIntWidth())
Ty = Context.IntTy;
else if (pw == Context.getTargetInfo().getLongWidth())
Ty = Context.LongTy;
else if (pw == Context.getTargetInfo().getLongLongWidth())
Ty = Context.LongLongTy;
else {
llvm_unreachable("I don't know size of pointer!");
}
return new (Context) GNUNullExpr(Ty, TokenLoc);
}
bool Sema::ConversionToObjCStringLiteralCheck(QualType DstType, Expr *&Exp,
bool Diagnose) {
if (!getLangOpts().ObjC1)
return false;
const ObjCObjectPointerType *PT = DstType->getAs<ObjCObjectPointerType>();
if (!PT)
return false;
if (!PT->isObjCIdType()) {
// Check if the destination is the 'NSString' interface.
const ObjCInterfaceDecl *ID = PT->getInterfaceDecl();
if (!ID || !ID->getIdentifier()->isStr("NSString"))
return false;
}
// Ignore any parens, implicit casts (should only be
// array-to-pointer decays), and not-so-opaque values. The last is
// important for making this trigger for property assignments.
Expr *SrcExpr = Exp->IgnoreParenImpCasts();
if (OpaqueValueExpr *OV = dyn_cast<OpaqueValueExpr>(SrcExpr))
if (OV->getSourceExpr())
SrcExpr = OV->getSourceExpr()->IgnoreParenImpCasts();
StringLiteral *SL = dyn_cast<StringLiteral>(SrcExpr);
if (!SL || !SL->isAscii())
return false;
if (Diagnose) {
Diag(SL->getLocStart(), diag::err_missing_atsign_prefix)
<< FixItHint::CreateInsertion(SL->getLocStart(), "@");
Exp = BuildObjCStringLiteral(SL->getLocStart(), SL).get();
}
return true;
}
static bool maybeDiagnoseAssignmentToFunction(Sema &S, QualType DstType,
const Expr *SrcExpr) {
if (!DstType->isFunctionPointerType() ||
!SrcExpr->getType()->isFunctionType())
return false;
auto *DRE = dyn_cast<DeclRefExpr>(SrcExpr->IgnoreParenImpCasts());
if (!DRE)
return false;
auto *FD = dyn_cast<FunctionDecl>(DRE->getDecl());
if (!FD)
return false;
return !S.checkAddressOfFunctionIsAvailable(FD,
/*Complain=*/true,
SrcExpr->getLocStart());
}
bool Sema::DiagnoseAssignmentResult(AssignConvertType ConvTy,
SourceLocation Loc,
QualType DstType, QualType SrcType,
Expr *SrcExpr, AssignmentAction Action,
bool *Complained) {
if (Complained)
*Complained = false;
// Decode the result (notice that AST's are still created for extensions).
bool CheckInferredResultType = false;
bool isInvalid = false;
unsigned DiagKind = 0;
FixItHint Hint;
ConversionFixItGenerator ConvHints;
bool MayHaveConvFixit = false;
bool MayHaveFunctionDiff = false;
const ObjCInterfaceDecl *IFace = nullptr;
const ObjCProtocolDecl *PDecl = nullptr;
switch (ConvTy) {
case Compatible:
DiagnoseAssignmentEnum(DstType, SrcType, SrcExpr);
return false;
case PointerToInt:
DiagKind = diag::ext_typecheck_convert_pointer_int;
ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
MayHaveConvFixit = true;
break;
case IntToPointer:
DiagKind = diag::ext_typecheck_convert_int_pointer;
ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
MayHaveConvFixit = true;
break;
case IncompatiblePointer:
if (Action == AA_Passing_CFAudited)
DiagKind = diag::err_arc_typecheck_convert_incompatible_pointer;
else if (SrcType->isFunctionPointerType() &&
DstType->isFunctionPointerType())
DiagKind = diag::ext_typecheck_convert_incompatible_function_pointer;
else
DiagKind = diag::ext_typecheck_convert_incompatible_pointer;
CheckInferredResultType = DstType->isObjCObjectPointerType() &&
SrcType->isObjCObjectPointerType();
if (Hint.isNull() && !CheckInferredResultType) {
ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
}
else if (CheckInferredResultType) {
SrcType = SrcType.getUnqualifiedType();
DstType = DstType.getUnqualifiedType();
}
MayHaveConvFixit = true;
break;
case IncompatiblePointerSign:
DiagKind = diag::ext_typecheck_convert_incompatible_pointer_sign;
break;
case FunctionVoidPointer:
DiagKind = diag::ext_typecheck_convert_pointer_void_func;
break;
case IncompatiblePointerDiscardsQualifiers: {
// Perform array-to-pointer decay if necessary.
if (SrcType->isArrayType()) SrcType = Context.getArrayDecayedType(SrcType);
Qualifiers lhq = SrcType->getPointeeType().getQualifiers();
Qualifiers rhq = DstType->getPointeeType().getQualifiers();
if (lhq.getAddressSpace() != rhq.getAddressSpace()) {
DiagKind = diag::err_typecheck_incompatible_address_space;
break;
} else if (lhq.getObjCLifetime() != rhq.getObjCLifetime()) {
DiagKind = diag::err_typecheck_incompatible_ownership;
break;
}
llvm_unreachable("unknown error case for discarding qualifiers!");
// fallthrough
}
case CompatiblePointerDiscardsQualifiers:
// If the qualifiers lost were because we were applying the
// (deprecated) C++ conversion from a string literal to a char*
// (or wchar_t*), then there was no error (C++ 4.2p2). FIXME:
// Ideally, this check would be performed in
// checkPointerTypesForAssignment. However, that would require a
// bit of refactoring (so that the second argument is an
// expression, rather than a type), which should be done as part
// of a larger effort to fix checkPointerTypesForAssignment for
// C++ semantics.
if (getLangOpts().CPlusPlus &&
IsStringLiteralToNonConstPointerConversion(SrcExpr, DstType))
return false;
DiagKind = diag::ext_typecheck_convert_discards_qualifiers;
break;
case IncompatibleNestedPointerQualifiers:
DiagKind = diag::ext_nested_pointer_qualifier_mismatch;
break;
case IntToBlockPointer:
DiagKind = diag::err_int_to_block_pointer;
break;
case IncompatibleBlockPointer:
DiagKind = diag::err_typecheck_convert_incompatible_block_pointer;
break;
case IncompatibleObjCQualifiedId: {
if (SrcType->isObjCQualifiedIdType()) {
const ObjCObjectPointerType *srcOPT =
SrcType->getAs<ObjCObjectPointerType>();
for (auto *srcProto : srcOPT->quals()) {
PDecl = srcProto;
break;
}
if (const ObjCInterfaceType *IFaceT =
DstType->getAs<ObjCObjectPointerType>()->getInterfaceType())
IFace = IFaceT->getDecl();
}
else if (DstType->isObjCQualifiedIdType()) {
const ObjCObjectPointerType *dstOPT =
DstType->getAs<ObjCObjectPointerType>();
for (auto *dstProto : dstOPT->quals()) {
PDecl = dstProto;
break;
}
if (const ObjCInterfaceType *IFaceT =
SrcType->getAs<ObjCObjectPointerType>()->getInterfaceType())
IFace = IFaceT->getDecl();
}
DiagKind = diag::warn_incompatible_qualified_id;
break;
}
case IncompatibleVectors:
DiagKind = diag::warn_incompatible_vectors;
break;
case IncompatibleObjCWeakRef:
DiagKind = diag::err_arc_weak_unavailable_assign;
break;
case Incompatible:
if (maybeDiagnoseAssignmentToFunction(*this, DstType, SrcExpr)) {
if (Complained)
*Complained = true;
return true;
}
DiagKind = diag::err_typecheck_convert_incompatible;
ConvHints.tryToFixConversion(SrcExpr, SrcType, DstType, *this);
MayHaveConvFixit = true;
isInvalid = true;
MayHaveFunctionDiff = true;
break;
}
QualType FirstType, SecondType;
switch (Action) {
case AA_Assigning:
case AA_Initializing:
// The destination type comes first.
FirstType = DstType;
SecondType = SrcType;
break;
case AA_Returning:
case AA_Passing:
case AA_Passing_CFAudited:
case AA_Converting:
case AA_Sending:
case AA_Casting:
// The source type comes first.
FirstType = SrcType;
SecondType = DstType;
break;
}
PartialDiagnostic FDiag = PDiag(DiagKind);
if (Action == AA_Passing_CFAudited)
FDiag << FirstType << SecondType << AA_Passing << SrcExpr->getSourceRange();
else
FDiag << FirstType << SecondType << Action << SrcExpr->getSourceRange();
// If we can fix the conversion, suggest the FixIts.
assert(ConvHints.isNull() || Hint.isNull());
if (!ConvHints.isNull()) {
for (FixItHint &H : ConvHints.Hints)
FDiag << H;
} else {
FDiag << Hint;
}
if (MayHaveConvFixit) { FDiag << (unsigned) (ConvHints.Kind); }
if (MayHaveFunctionDiff)
HandleFunctionTypeMismatch(FDiag, SecondType, FirstType);
Diag(Loc, FDiag);
if (DiagKind == diag::warn_incompatible_qualified_id &&
PDecl && IFace && !IFace->hasDefinition())
Diag(IFace->getLocation(), diag::note_incomplete_class_and_qualified_id)
<< IFace << PDecl;
if (SecondType == Context.OverloadTy)
NoteAllOverloadCandidates(OverloadExpr::find(SrcExpr).Expression,
FirstType, /*TakingAddress=*/true);
if (CheckInferredResultType)
EmitRelatedResultTypeNote(SrcExpr);
if (Action == AA_Returning && ConvTy == IncompatiblePointer)
EmitRelatedResultTypeNoteForReturn(DstType);
if (Complained)
*Complained = true;
return isInvalid;
}
ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
llvm::APSInt *Result) {
class SimpleICEDiagnoser : public VerifyICEDiagnoser {
public:
void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) override {
S.Diag(Loc, diag::err_expr_not_ice) << S.LangOpts.CPlusPlus << SR;
}
} Diagnoser;
return VerifyIntegerConstantExpression(E, Result, Diagnoser);
}
ExprResult Sema::VerifyIntegerConstantExpression(Expr *E,
llvm::APSInt *Result,
unsigned DiagID,
bool AllowFold) {
class IDDiagnoser : public VerifyICEDiagnoser {
unsigned DiagID;
public:
IDDiagnoser(unsigned DiagID)
: VerifyICEDiagnoser(DiagID == 0), DiagID(DiagID) { }
void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) override {
S.Diag(Loc, DiagID) << SR;
}
} Diagnoser(DiagID);
return VerifyIntegerConstantExpression(E, Result, Diagnoser, AllowFold);
}
void Sema::VerifyICEDiagnoser::diagnoseFold(Sema &S, SourceLocation Loc,
SourceRange SR) {
S.Diag(Loc, diag::ext_expr_not_ice) << SR << S.LangOpts.CPlusPlus;
}
ExprResult
Sema::VerifyIntegerConstantExpression(Expr *E, llvm::APSInt *Result,
VerifyICEDiagnoser &Diagnoser,
bool AllowFold) {
SourceLocation DiagLoc = E->getLocStart();
if (getLangOpts().CPlusPlus11) {
// C++11 [expr.const]p5:
// If an expression of literal class type is used in a context where an
// integral constant expression is required, then that class type shall
// have a single non-explicit conversion function to an integral or
// unscoped enumeration type
ExprResult Converted;
class CXX11ConvertDiagnoser : public ICEConvertDiagnoser {
public:
CXX11ConvertDiagnoser(bool Silent)
: ICEConvertDiagnoser(/*AllowScopedEnumerations*/false,
Silent, true) {}
SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
QualType T) override {
return S.Diag(Loc, diag::err_ice_not_integral) << T;
}
SemaDiagnosticBuilder diagnoseIncomplete(
Sema &S, SourceLocation Loc, QualType T) override {
return S.Diag(Loc, diag::err_ice_incomplete_type) << T;
}
SemaDiagnosticBuilder diagnoseExplicitConv(
Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
return S.Diag(Loc, diag::err_ice_explicit_conversion) << T << ConvTy;
}
SemaDiagnosticBuilder noteExplicitConv(
Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here)
<< ConvTy->isEnumeralType() << ConvTy;
}
SemaDiagnosticBuilder diagnoseAmbiguous(
Sema &S, SourceLocation Loc, QualType T) override {
return S.Diag(Loc, diag::err_ice_ambiguous_conversion) << T;
}
SemaDiagnosticBuilder noteAmbiguous(
Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
return S.Diag(Conv->getLocation(), diag::note_ice_conversion_here)
<< ConvTy->isEnumeralType() << ConvTy;
}
SemaDiagnosticBuilder diagnoseConversion(
Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
llvm_unreachable("conversion functions are permitted");
}
} ConvertDiagnoser(Diagnoser.Suppress);
Converted = PerformContextualImplicitConversion(DiagLoc, E,
ConvertDiagnoser);
if (Converted.isInvalid())
return Converted;
E = Converted.get();
if (!E->getType()->isIntegralOrUnscopedEnumerationType())
return ExprError();
} else if (!E->getType()->isIntegralOrUnscopedEnumerationType()) {
// An ICE must be of integral or unscoped enumeration type.
if (!Diagnoser.Suppress)
Diagnoser.diagnoseNotICE(*this, DiagLoc, E->getSourceRange());
return ExprError();
}
// Circumvent ICE checking in C++11 to avoid evaluating the expression twice
// in the non-ICE case.
if (!getLangOpts().CPlusPlus11 && E->isIntegerConstantExpr(Context)) {
if (Result)
*Result = E->EvaluateKnownConstInt(Context);
return E;
}
Expr::EvalResult EvalResult;
SmallVector<PartialDiagnosticAt, 8> Notes;
EvalResult.Diag = &Notes;
// Try to evaluate the expression, and produce diagnostics explaining why it's
// not a constant expression as a side-effect.
bool Folded = E->EvaluateAsRValue(EvalResult, Context) &&
EvalResult.Val.isInt() && !EvalResult.HasSideEffects;
// In C++11, we can rely on diagnostics being produced for any expression
// which is not a constant expression. If no diagnostics were produced, then
// this is a constant expression.
if (Folded && getLangOpts().CPlusPlus11 && Notes.empty()) {
if (Result)
*Result = EvalResult.Val.getInt();
return E;
}
// If our only note is the usual "invalid subexpression" note, just point
// the caret at its location rather than producing an essentially
// redundant note.
if (Notes.size() == 1 && Notes[0].second.getDiagID() ==
diag::note_invalid_subexpr_in_const_expr) {
DiagLoc = Notes[0].first;
Notes.clear();
}
if (!Folded || !AllowFold) {
if (!Diagnoser.Suppress) {
Diagnoser.diagnoseNotICE(*this, DiagLoc, E->getSourceRange());
for (const PartialDiagnosticAt &Note : Notes)
Diag(Note.first, Note.second);
}
return ExprError();
}
Diagnoser.diagnoseFold(*this, DiagLoc, E->getSourceRange());
for (const PartialDiagnosticAt &Note : Notes)
Diag(Note.first, Note.second);
if (Result)
*Result = EvalResult.Val.getInt();
return E;
}
namespace {
// Handle the case where we conclude a expression which we speculatively
// considered to be unevaluated is actually evaluated.
class TransformToPE : public TreeTransform<TransformToPE> {
typedef TreeTransform<TransformToPE> BaseTransform;
public:
TransformToPE(Sema &SemaRef) : BaseTransform(SemaRef) { }
// Make sure we redo semantic analysis
bool AlwaysRebuild() { return true; }
// Make sure we handle LabelStmts correctly.
// FIXME: This does the right thing, but maybe we need a more general
// fix to TreeTransform?
StmtResult TransformLabelStmt(LabelStmt *S) {
S->getDecl()->setStmt(nullptr);
return BaseTransform::TransformLabelStmt(S);
}
// We need to special-case DeclRefExprs referring to FieldDecls which
// are not part of a member pointer formation; normal TreeTransforming
// doesn't catch this case because of the way we represent them in the AST.
// FIXME: This is a bit ugly; is it really the best way to handle this
// case?
//
// Error on DeclRefExprs referring to FieldDecls.
ExprResult TransformDeclRefExpr(DeclRefExpr *E) {
if (isa<FieldDecl>(E->getDecl()) &&
!SemaRef.isUnevaluatedContext())
return SemaRef.Diag(E->getLocation(),
diag::err_invalid_non_static_member_use)
<< E->getDecl() << E->getSourceRange();
return BaseTransform::TransformDeclRefExpr(E);
}
// Exception: filter out member pointer formation
ExprResult TransformUnaryOperator(UnaryOperator *E) {
if (E->getOpcode() == UO_AddrOf && E->getType()->isMemberPointerType())
return E;
return BaseTransform::TransformUnaryOperator(E);
}
ExprResult TransformLambdaExpr(LambdaExpr *E) {
// Lambdas never need to be transformed.
return E;
}
};
}
ExprResult Sema::TransformToPotentiallyEvaluated(Expr *E) {
assert(isUnevaluatedContext() &&
"Should only transform unevaluated expressions");
ExprEvalContexts.back().Context =
ExprEvalContexts[ExprEvalContexts.size()-2].Context;
if (isUnevaluatedContext())
return E;
return TransformToPE(*this).TransformExpr(E);
}
void
Sema::PushExpressionEvaluationContext(
ExpressionEvaluationContext NewContext, Decl *LambdaContextDecl,
ExpressionEvaluationContextRecord::ExpressionKind ExprContext) {
ExprEvalContexts.emplace_back(NewContext, ExprCleanupObjects.size(), Cleanup,
LambdaContextDecl, ExprContext);
Cleanup.reset();
if (!MaybeODRUseExprs.empty())
std::swap(MaybeODRUseExprs, ExprEvalContexts.back().SavedMaybeODRUseExprs);
}
void
Sema::PushExpressionEvaluationContext(
ExpressionEvaluationContext NewContext, ReuseLambdaContextDecl_t,
ExpressionEvaluationContextRecord::ExpressionKind ExprContext) {
Decl *ClosureContextDecl = ExprEvalContexts.back().ManglingContextDecl;
PushExpressionEvaluationContext(NewContext, ClosureContextDecl, ExprContext);
}
void Sema::PopExpressionEvaluationContext() {
ExpressionEvaluationContextRecord& Rec = ExprEvalContexts.back();
unsigned NumTypos = Rec.NumTypos;
if (!Rec.Lambdas.empty()) {
using ExpressionKind = ExpressionEvaluationContextRecord::ExpressionKind;
if (Rec.ExprContext == ExpressionKind::EK_TemplateArgument || Rec.isUnevaluated() ||
(Rec.isConstantEvaluated() && !getLangOpts().CPlusPlus17)) {
unsigned D;
if (Rec.isUnevaluated()) {
// C++11 [expr.prim.lambda]p2:
// A lambda-expression shall not appear in an unevaluated operand
// (Clause 5).
D = diag::err_lambda_unevaluated_operand;
} else if (Rec.isConstantEvaluated() && !getLangOpts().CPlusPlus17) {
// C++1y [expr.const]p2:
// A conditional-expression e is a core constant expression unless the
// evaluation of e, following the rules of the abstract machine, would
// evaluate [...] a lambda-expression.
D = diag::err_lambda_in_constant_expression;
} else if (Rec.ExprContext == ExpressionKind::EK_TemplateArgument) {
// C++17 [expr.prim.lamda]p2:
// A lambda-expression shall not appear [...] in a template-argument.
D = diag::err_lambda_in_invalid_context;
} else
llvm_unreachable("Couldn't infer lambda error message.");
for (const auto *L : Rec.Lambdas)
Diag(L->getLocStart(), D);
} else {
// Mark the capture expressions odr-used. This was deferred
// during lambda expression creation.
for (auto *Lambda : Rec.Lambdas) {
for (auto *C : Lambda->capture_inits())
MarkDeclarationsReferencedInExpr(C);
}
}
}
// When are coming out of an unevaluated context, clear out any
// temporaries that we may have created as part of the evaluation of
// the expression in that context: they aren't relevant because they
// will never be constructed.
if (Rec.isUnevaluated() || Rec.isConstantEvaluated()) {
ExprCleanupObjects.erase(ExprCleanupObjects.begin() + Rec.NumCleanupObjects,
ExprCleanupObjects.end());
Cleanup = Rec.ParentCleanup;
CleanupVarDeclMarking();
std::swap(MaybeODRUseExprs, Rec.SavedMaybeODRUseExprs);
// Otherwise, merge the contexts together.
} else {
Cleanup.mergeFrom(Rec.ParentCleanup);
MaybeODRUseExprs.insert(Rec.SavedMaybeODRUseExprs.begin(),
Rec.SavedMaybeODRUseExprs.end());
}
// Pop the current expression evaluation context off the stack.
ExprEvalContexts.pop_back();
if (!ExprEvalContexts.empty())
ExprEvalContexts.back().NumTypos += NumTypos;
else
assert(NumTypos == 0 && "There are outstanding typos after popping the "
"last ExpressionEvaluationContextRecord");
}
void Sema::DiscardCleanupsInEvaluationContext() {
ExprCleanupObjects.erase(
ExprCleanupObjects.begin() + ExprEvalContexts.back().NumCleanupObjects,
ExprCleanupObjects.end());
Cleanup.reset();
MaybeODRUseExprs.clear();
}
ExprResult Sema::HandleExprEvaluationContextForTypeof(Expr *E) {
if (!E->getType()->isVariablyModifiedType())
return E;
return TransformToPotentiallyEvaluated(E);
}
/// Are we within a context in which some evaluation could be performed (be it
/// constant evaluation or runtime evaluation)? Sadly, this notion is not quite
/// captured by C++'s idea of an "unevaluated context".
static bool isEvaluatableContext(Sema &SemaRef) {
switch (SemaRef.ExprEvalContexts.back().Context) {
case Sema::ExpressionEvaluationContext::Unevaluated:
case Sema::ExpressionEvaluationContext::UnevaluatedAbstract:
// Expressions in this context are never evaluated.
return false;
case Sema::ExpressionEvaluationContext::UnevaluatedList:
case Sema::ExpressionEvaluationContext::ConstantEvaluated:
case Sema::ExpressionEvaluationContext::PotentiallyEvaluated:
case Sema::ExpressionEvaluationContext::DiscardedStatement:
// Expressions in this context could be evaluated.
return true;
case Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
// Referenced declarations will only be used if the construct in the
// containing expression is used, at which point we'll be given another
// turn to mark them.
return false;
}
llvm_unreachable("Invalid context");
}
/// Are we within a context in which references to resolved functions or to
/// variables result in odr-use?
static bool isOdrUseContext(Sema &SemaRef, bool SkipDependentUses = true) {
// An expression in a template is not really an expression until it's been
// instantiated, so it doesn't trigger odr-use.
if (SkipDependentUses && SemaRef.CurContext->isDependentContext())
return false;
switch (SemaRef.ExprEvalContexts.back().Context) {
case Sema::ExpressionEvaluationContext::Unevaluated:
case Sema::ExpressionEvaluationContext::UnevaluatedList:
case Sema::ExpressionEvaluationContext::UnevaluatedAbstract:
case Sema::ExpressionEvaluationContext::DiscardedStatement:
return false;
case Sema::ExpressionEvaluationContext::ConstantEvaluated:
case Sema::ExpressionEvaluationContext::PotentiallyEvaluated:
return true;
case Sema::ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
return false;
}
llvm_unreachable("Invalid context");
}
static bool isImplicitlyDefinableConstexprFunction(FunctionDecl *Func) {
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Func);
return Func->isConstexpr() &&
(Func->isImplicitlyInstantiable() || (MD && !MD->isUserProvided()));
}
/// Mark a function referenced, and check whether it is odr-used
/// (C++ [basic.def.odr]p2, C99 6.9p3)
void Sema::MarkFunctionReferenced(SourceLocation Loc, FunctionDecl *Func,
bool MightBeOdrUse) {
assert(Func && "No function?");
Func->setReferenced();
// C++11 [basic.def.odr]p3:
// A function whose name appears as a potentially-evaluated expression is
// odr-used if it is the unique lookup result or the selected member of a
// set of overloaded functions [...].
//
// We (incorrectly) mark overload resolution as an unevaluated context, so we
// can just check that here.
bool OdrUse = MightBeOdrUse && isOdrUseContext(*this);
// Determine whether we require a function definition to exist, per
// C++11 [temp.inst]p3:
// Unless a function template specialization has been explicitly
// instantiated or explicitly specialized, the function template
// specialization is implicitly instantiated when the specialization is
// referenced in a context that requires a function definition to exist.
//
// That is either when this is an odr-use, or when a usage of a constexpr
// function occurs within an evaluatable context.
bool NeedDefinition =
OdrUse || (isEvaluatableContext(*this) &&
isImplicitlyDefinableConstexprFunction(Func));
// C++14 [temp.expl.spec]p6:
// If a template [...] is explicitly specialized then that specialization
// shall be declared before the first use of that specialization that would
// cause an implicit instantiation to take place, in every translation unit
// in which such a use occurs
if (NeedDefinition &&
(Func->getTemplateSpecializationKind() != TSK_Undeclared ||
Func->getMemberSpecializationInfo()))
checkSpecializationVisibility(Loc, Func);
// C++14 [except.spec]p17:
// An exception-specification is considered to be needed when:
// - the function is odr-used or, if it appears in an unevaluated operand,
// would be odr-used if the expression were potentially-evaluated;
//
// Note, we do this even if MightBeOdrUse is false. That indicates that the
// function is a pure virtual function we're calling, and in that case the
// function was selected by overload resolution and we need to resolve its
// exception specification for a different reason.
const FunctionProtoType *FPT = Func->getType()->getAs<FunctionProtoType>();
if (FPT && isUnresolvedExceptionSpec(FPT->getExceptionSpecType()))
ResolveExceptionSpec(Loc, FPT);
// If we don't need to mark the function as used, and we don't need to
// try to provide a definition, there's nothing more to do.
if ((Func->isUsed(/*CheckUsedAttr=*/false) || !OdrUse) &&
(!NeedDefinition || Func->getBody()))
return;
// Note that this declaration has been used.
if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Func)) {
Constructor = cast<CXXConstructorDecl>(Constructor->getFirstDecl());
if (Constructor->isDefaulted() && !Constructor->isDeleted()) {
if (Constructor->isDefaultConstructor()) {
if (Constructor->isTrivial() && !Constructor->hasAttr<DLLExportAttr>())
return;
DefineImplicitDefaultConstructor(Loc, Constructor);
} else if (Constructor->isCopyConstructor()) {
DefineImplicitCopyConstructor(Loc, Constructor);
} else if (Constructor->isMoveConstructor()) {
DefineImplicitMoveConstructor(Loc, Constructor);
}
} else if (Constructor->getInheritedConstructor()) {
DefineInheritingConstructor(Loc, Constructor);
}
} else if (CXXDestructorDecl *Destructor =
dyn_cast<CXXDestructorDecl>(Func)) {
Destructor = cast<CXXDestructorDecl>(Destructor->getFirstDecl());
if (Destructor->isDefaulted() && !Destructor->isDeleted()) {
if (Destructor->isTrivial() && !Destructor->hasAttr<DLLExportAttr>())
return;
DefineImplicitDestructor(Loc, Destructor);
}
if (Destructor->isVirtual() && getLangOpts().AppleKext)
MarkVTableUsed(Loc, Destructor->getParent());
} else if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(Func)) {
if (MethodDecl->isOverloadedOperator() &&
MethodDecl->getOverloadedOperator() == OO_Equal) {
MethodDecl = cast<CXXMethodDecl>(MethodDecl->getFirstDecl());
if (MethodDecl->isDefaulted() && !MethodDecl->isDeleted()) {
if (MethodDecl->isCopyAssignmentOperator())
DefineImplicitCopyAssignment(Loc, MethodDecl);
else if (MethodDecl->isMoveAssignmentOperator())
DefineImplicitMoveAssignment(Loc, MethodDecl);
}
} else if (isa<CXXConversionDecl>(MethodDecl) &&
MethodDecl->getParent()->isLambda()) {
CXXConversionDecl *Conversion =
cast<CXXConversionDecl>(MethodDecl->getFirstDecl());
if (Conversion->isLambdaToBlockPointerConversion())
DefineImplicitLambdaToBlockPointerConversion(Loc, Conversion);
else
DefineImplicitLambdaToFunctionPointerConversion(Loc, Conversion);
} else if (MethodDecl->isVirtual() && getLangOpts().AppleKext)
MarkVTableUsed(Loc, MethodDecl->getParent());
}
// Recursive functions should be marked when used from another function.
// FIXME: Is this really right?
if (CurContext == Func) return;
// Implicit instantiation of function templates and member functions of
// class templates.
if (Func->isImplicitlyInstantiable()) {
TemplateSpecializationKind TSK = Func->getTemplateSpecializationKind();
SourceLocation PointOfInstantiation = Func->getPointOfInstantiation();
bool FirstInstantiation = PointOfInstantiation.isInvalid();
if (FirstInstantiation) {
PointOfInstantiation = Loc;
Func->setTemplateSpecializationKind(TSK, PointOfInstantiation);
} else if (TSK != TSK_ImplicitInstantiation) {
// Use the point of use as the point of instantiation, instead of the
// point of explicit instantiation (which we track as the actual point of
// instantiation). This gives better backtraces in diagnostics.
PointOfInstantiation = Loc;
}
if (FirstInstantiation || TSK != TSK_ImplicitInstantiation ||
Func->isConstexpr()) {
if (isa<CXXRecordDecl>(Func->getDeclContext()) &&
cast<CXXRecordDecl>(Func->getDeclContext())->isLocalClass() &&
CodeSynthesisContexts.size())
PendingLocalImplicitInstantiations.push_back(
std::make_pair(Func, PointOfInstantiation));
else if (Func->isConstexpr())
// Do not defer instantiations of constexpr functions, to avoid the
// expression evaluator needing to call back into Sema if it sees a
// call to such a function.
InstantiateFunctionDefinition(PointOfInstantiation, Func);
else {
Func->setInstantiationIsPending(true);
PendingInstantiations.push_back(std::make_pair(Func,
PointOfInstantiation));
// Notify the consumer that a function was implicitly instantiated.
Consumer.HandleCXXImplicitFunctionInstantiation(Func);
}
}
} else {
// Walk redefinitions, as some of them may be instantiable.
for (auto i : Func->redecls()) {
if (!i->isUsed(false) && i->isImplicitlyInstantiable())
MarkFunctionReferenced(Loc, i, OdrUse);
}
}
if (!OdrUse) return;
// Keep track of used but undefined functions.
if (!Func->isDefined()) {
if (mightHaveNonExternalLinkage(Func))
UndefinedButUsed.insert(std::make_pair(Func->getCanonicalDecl(), Loc));
else if (Func->getMostRecentDecl()->isInlined() &&
!LangOpts.GNUInline &&
!Func->getMostRecentDecl()->hasAttr<GNUInlineAttr>())
UndefinedButUsed.insert(std::make_pair(Func->getCanonicalDecl(), Loc));
else if (isExternalWithNoLinkageType(Func))
UndefinedButUsed.insert(std::make_pair(Func->getCanonicalDecl(), Loc));
}
Func->markUsed(Context);
}
static void
diagnoseUncapturableValueReference(Sema &S, SourceLocation loc,
ValueDecl *var, DeclContext *DC) {
DeclContext *VarDC = var->getDeclContext();
// If the parameter still belongs to the translation unit, then
// we're actually just using one parameter in the declaration of
// the next.
if (isa<ParmVarDecl>(var) &&
isa<TranslationUnitDecl>(VarDC))
return;
// For C code, don't diagnose about capture if we're not actually in code
// right now; it's impossible to write a non-constant expression outside of
// function context, so we'll get other (more useful) diagnostics later.
//
// For C++, things get a bit more nasty... it would be nice to suppress this
// diagnostic for certain cases like using a local variable in an array bound
// for a member of a local class, but the correct predicate is not obvious.
if (!S.getLangOpts().CPlusPlus && !S.CurContext->isFunctionOrMethod())
return;
unsigned ValueKind = isa<BindingDecl>(var) ? 1 : 0;
unsigned ContextKind = 3; // unknown
if (isa<CXXMethodDecl>(VarDC) &&
cast<CXXRecordDecl>(VarDC->getParent())->isLambda()) {
ContextKind = 2;
} else if (isa<FunctionDecl>(VarDC)) {
ContextKind = 0;
} else if (isa<BlockDecl>(VarDC)) {
ContextKind = 1;
}
S.Diag(loc, diag::err_reference_to_local_in_enclosing_context)
<< var << ValueKind << ContextKind << VarDC;
S.Diag(var->getLocation(), diag::note_entity_declared_at)
<< var;
// FIXME: Add additional diagnostic info about class etc. which prevents
// capture.
}
static bool isVariableAlreadyCapturedInScopeInfo(CapturingScopeInfo *CSI, VarDecl *Var,
bool &SubCapturesAreNested,
QualType &CaptureType,
QualType &DeclRefType) {
// Check whether we've already captured it.
if (CSI->CaptureMap.count(Var)) {
// If we found a capture, any subcaptures are nested.
SubCapturesAreNested = true;
// Retrieve the capture type for this variable.
CaptureType = CSI->getCapture(Var).getCaptureType();
// Compute the type of an expression that refers to this variable.
DeclRefType = CaptureType.getNonReferenceType();
// Similarly to mutable captures in lambda, all the OpenMP captures by copy
// are mutable in the sense that user can change their value - they are
// private instances of the captured declarations.
const Capture &Cap = CSI->getCapture(Var);
if (Cap.isCopyCapture() &&
!(isa<LambdaScopeInfo>(CSI) && cast<LambdaScopeInfo>(CSI)->Mutable) &&
!(isa<CapturedRegionScopeInfo>(CSI) &&
cast<CapturedRegionScopeInfo>(CSI)->CapRegionKind == CR_OpenMP))
DeclRefType.addConst();
return true;
}
return false;
}
// Only block literals, captured statements, and lambda expressions can
// capture; other scopes don't work.
static DeclContext *getParentOfCapturingContextOrNull(DeclContext *DC, VarDecl *Var,
SourceLocation Loc,
const bool Diagnose, Sema &S) {
if (isa<BlockDecl>(DC) || isa<CapturedDecl>(DC) || isLambdaCallOperator(DC))
return getLambdaAwareParentOfDeclContext(DC);
else if (Var->hasLocalStorage()) {
if (Diagnose)
diagnoseUncapturableValueReference(S, Loc, Var, DC);
}
return nullptr;
}
// Certain capturing entities (lambdas, blocks etc.) are not allowed to capture
// certain types of variables (unnamed, variably modified types etc.)
// so check for eligibility.
static bool isVariableCapturable(CapturingScopeInfo *CSI, VarDecl *Var,
SourceLocation Loc,
const bool Diagnose, Sema &S) {
bool IsBlock = isa<BlockScopeInfo>(CSI);
bool IsLambda = isa<LambdaScopeInfo>(CSI);
// Lambdas are not allowed to capture unnamed variables
// (e.g. anonymous unions).
// FIXME: The C++11 rule don't actually state this explicitly, but I'm
// assuming that's the intent.
if (IsLambda && !Var->getDeclName()) {
if (Diagnose) {
S.Diag(Loc, diag::err_lambda_capture_anonymous_var);
S.Diag(Var->getLocation(), diag::note_declared_at);
}
return false;
}
// Prohibit variably-modified types in blocks; they're difficult to deal with.
if (Var->getType()->isVariablyModifiedType() && IsBlock) {
if (Diagnose) {
S.Diag(Loc, diag::err_ref_vm_type);
S.Diag(Var->getLocation(), diag::note_previous_decl)
<< Var->getDeclName();
}
return false;
}
// Prohibit structs with flexible array members too.
// We cannot capture what is in the tail end of the struct.
if (const RecordType *VTTy = Var->getType()->getAs<RecordType>()) {
if (VTTy->getDecl()->hasFlexibleArrayMember()) {
if (Diagnose) {
if (IsBlock)
S.Diag(Loc, diag::err_ref_flexarray_type);
else
S.Diag(Loc, diag::err_lambda_capture_flexarray_type)
<< Var->getDeclName();
S.Diag(Var->getLocation(), diag::note_previous_decl)
<< Var->getDeclName();
}
return false;
}
}
const bool HasBlocksAttr = Var->hasAttr<BlocksAttr>();
// Lambdas and captured statements are not allowed to capture __block
// variables; they don't support the expected semantics.
if (HasBlocksAttr && (IsLambda || isa<CapturedRegionScopeInfo>(CSI))) {
if (Diagnose) {
S.Diag(Loc, diag::err_capture_block_variable)
<< Var->getDeclName() << !IsLambda;
S.Diag(Var->getLocation(), diag::note_previous_decl)
<< Var->getDeclName();
}
return false;
}
// OpenCL v2.0 s6.12.5: Blocks cannot reference/capture other blocks
if (S.getLangOpts().OpenCL && IsBlock &&
Var->getType()->isBlockPointerType()) {
if (Diagnose)
S.Diag(Loc, diag::err_opencl_block_ref_block);
return false;
}
return true;
}
// Returns true if the capture by block was successful.
static bool captureInBlock(BlockScopeInfo *BSI, VarDecl *Var,
SourceLocation Loc,
const bool BuildAndDiagnose,
QualType &CaptureType,
QualType &DeclRefType,
const bool Nested,
Sema &S) {
Expr *CopyExpr = nullptr;
bool ByRef = false;
// Blocks are not allowed to capture arrays.
if (CaptureType->isArrayType()) {
if (BuildAndDiagnose) {
S.Diag(Loc, diag::err_ref_array_type);
S.Diag(Var->getLocation(), diag::note_previous_decl)
<< Var->getDeclName();
}
return false;
}
// Forbid the block-capture of autoreleasing variables.
if (CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) {
if (BuildAndDiagnose) {
S.Diag(Loc, diag::err_arc_autoreleasing_capture)
<< /*block*/ 0;
S.Diag(Var->getLocation(), diag::note_previous_decl)
<< Var->getDeclName();
}
return false;
}
// Warn about implicitly autoreleasing indirect parameters captured by blocks.
if (const auto *PT = CaptureType->getAs<PointerType>()) {
// This function finds out whether there is an AttributedType of kind
// attr_objc_ownership in Ty. The existence of AttributedType of kind
// attr_objc_ownership implies __autoreleasing was explicitly specified
// rather than being added implicitly by the compiler.
auto IsObjCOwnershipAttributedType = [](QualType Ty) {
while (const auto *AttrTy = Ty->getAs<AttributedType>()) {
if (AttrTy->getAttrKind() == AttributedType::attr_objc_ownership)
return true;
// Peel off AttributedTypes that are not of kind objc_ownership.
Ty = AttrTy->getModifiedType();
}
return false;
};
QualType PointeeTy = PT->getPointeeType();
if (PointeeTy->getAs<ObjCObjectPointerType>() &&
PointeeTy.getObjCLifetime() == Qualifiers::OCL_Autoreleasing &&
!IsObjCOwnershipAttributedType(PointeeTy)) {
if (BuildAndDiagnose) {
SourceLocation VarLoc = Var->getLocation();
S.Diag(Loc, diag::warn_block_capture_autoreleasing);
S.Diag(VarLoc, diag::note_declare_parameter_strong);
}
}
}
const bool HasBlocksAttr = Var->hasAttr<BlocksAttr>();
if (HasBlocksAttr || CaptureType->isReferenceType() ||
(S.getLangOpts().OpenMP && S.isOpenMPCapturedDecl(Var))) {
// Block capture by reference does not change the capture or
// declaration reference types.
ByRef = true;
} else {
// Block capture by copy introduces 'const'.
CaptureType = CaptureType.getNonReferenceType().withConst();
DeclRefType = CaptureType;
if (S.getLangOpts().CPlusPlus && BuildAndDiagnose) {
if (const RecordType *Record = DeclRefType->getAs<RecordType>()) {
// The capture logic needs the destructor, so make sure we mark it.
// Usually this is unnecessary because most local variables have
// their destructors marked at declaration time, but parameters are
// an exception because it's technically only the call site that
// actually requires the destructor.
if (isa<ParmVarDecl>(Var))
S.FinalizeVarWithDestructor(Var, Record);
// Enter a new evaluation context to insulate the copy
// full-expression.
EnterExpressionEvaluationContext scope(
S, Sema::ExpressionEvaluationContext::PotentiallyEvaluated);
// According to the blocks spec, the capture of a variable from
// the stack requires a const copy constructor. This is not true
// of the copy/move done to move a __block variable to the heap.
Expr *DeclRef = new (S.Context) DeclRefExpr(Var, Nested,
DeclRefType.withConst(),
VK_LValue, Loc);
ExprResult Result
= S.PerformCopyInitialization(
InitializedEntity::InitializeBlock(Var->getLocation(),
CaptureType, false),
Loc, DeclRef);
// Build a full-expression copy expression if initialization
// succeeded and used a non-trivial constructor. Recover from
// errors by pretending that the copy isn't necessary.
if (!Result.isInvalid() &&
!cast<CXXConstructExpr>(Result.get())->getConstructor()
->isTrivial()) {
Result = S.MaybeCreateExprWithCleanups(Result);
CopyExpr = Result.get();
}
}
}
}
// Actually capture the variable.
if (BuildAndDiagnose)
BSI->addCapture(Var, HasBlocksAttr, ByRef, Nested, Loc,
SourceLocation(), CaptureType, CopyExpr);
return true;
}
/// Capture the given variable in the captured region.
static bool captureInCapturedRegion(CapturedRegionScopeInfo *RSI,
VarDecl *Var,
SourceLocation Loc,
const bool BuildAndDiagnose,
QualType &CaptureType,
QualType &DeclRefType,
const bool RefersToCapturedVariable,
Sema &S) {
// By default, capture variables by reference.
bool ByRef = true;
// Using an LValue reference type is consistent with Lambdas (see below).
if (S.getLangOpts().OpenMP && RSI->CapRegionKind == CR_OpenMP) {
if (S.isOpenMPCapturedDecl(Var)) {
bool HasConst = DeclRefType.isConstQualified();
DeclRefType = DeclRefType.getUnqualifiedType();
// Don't lose diagnostics about assignments to const.
if (HasConst)
DeclRefType.addConst();
}
ByRef = S.isOpenMPCapturedByRef(Var, RSI->OpenMPLevel);
}
if (ByRef)
CaptureType = S.Context.getLValueReferenceType(DeclRefType);
else
CaptureType = DeclRefType;
Expr *CopyExpr = nullptr;
if (BuildAndDiagnose) {
// The current implementation assumes that all variables are captured
// by references. Since there is no capture by copy, no expression
// evaluation will be needed.
RecordDecl *RD = RSI->TheRecordDecl;
FieldDecl *Field
= FieldDecl::Create(S.Context, RD, Loc, Loc, nullptr, CaptureType,
S.Context.getTrivialTypeSourceInfo(CaptureType, Loc),
nullptr, false, ICIS_NoInit);
Field->setImplicit(true);
Field->setAccess(AS_private);
RD->addDecl(Field);
if (S.getLangOpts().OpenMP && RSI->CapRegionKind == CR_OpenMP)
S.setOpenMPCaptureKind(Field, Var, RSI->OpenMPLevel);
CopyExpr = new (S.Context) DeclRefExpr(Var, RefersToCapturedVariable,
DeclRefType, VK_LValue, Loc);
Var->setReferenced(true);
Var->markUsed(S.Context);
}
// Actually capture the variable.
if (BuildAndDiagnose)
RSI->addCapture(Var, /*isBlock*/false, ByRef, RefersToCapturedVariable, Loc,
SourceLocation(), CaptureType, CopyExpr);
return true;
}
/// Create a field within the lambda class for the variable
/// being captured.
static void addAsFieldToClosureType(Sema &S, LambdaScopeInfo *LSI,
QualType FieldType, QualType DeclRefType,
SourceLocation Loc,
bool RefersToCapturedVariable) {
CXXRecordDecl *Lambda = LSI->Lambda;
// Build the non-static data member.
FieldDecl *Field
= FieldDecl::Create(S.Context, Lambda, Loc, Loc, nullptr, FieldType,
S.Context.getTrivialTypeSourceInfo(FieldType, Loc),
nullptr, false, ICIS_NoInit);
Field->setImplicit(true);
Field->setAccess(AS_private);
Lambda->addDecl(Field);
}
/// Capture the given variable in the lambda.
static bool captureInLambda(LambdaScopeInfo *LSI,
VarDecl *Var,
SourceLocation Loc,
const bool BuildAndDiagnose,
QualType &CaptureType,
QualType &DeclRefType,
const bool RefersToCapturedVariable,
const Sema::TryCaptureKind Kind,
SourceLocation EllipsisLoc,
const bool IsTopScope,
Sema &S) {
// Determine whether we are capturing by reference or by value.
bool ByRef = false;
if (IsTopScope && Kind != Sema::TryCapture_Implicit) {
ByRef = (Kind == Sema::TryCapture_ExplicitByRef);
} else {
ByRef = (LSI->ImpCaptureStyle == LambdaScopeInfo::ImpCap_LambdaByref);
}
// Compute the type of the field that will capture this variable.
if (ByRef) {
// C++11 [expr.prim.lambda]p15:
// An entity is captured by reference if it is implicitly or
// explicitly captured but not captured by copy. It is
// unspecified whether additional unnamed non-static data
// members are declared in the closure type for entities
// captured by reference.
//
// FIXME: It is not clear whether we want to build an lvalue reference
// to the DeclRefType or to CaptureType.getNonReferenceType(). GCC appears
// to do the former, while EDG does the latter. Core issue 1249 will
// clarify, but for now we follow GCC because it's a more permissive and
// easily defensible position.
CaptureType = S.Context.getLValueReferenceType(DeclRefType);
} else {
// C++11 [expr.prim.lambda]p14:
// For each entity captured by copy, an unnamed non-static
// data member is declared in the closure type. The
// declaration order of these members is unspecified. The type
// of such a data member is the type of the corresponding
// captured entity if the entity is not a reference to an
// object, or the referenced type otherwise. [Note: If the
// captured entity is a reference to a function, the
// corresponding data member is also a reference to a
// function. - end note ]
if (const ReferenceType *RefType = CaptureType->getAs<ReferenceType>()){
if (!RefType->getPointeeType()->isFunctionType())
CaptureType = RefType->getPointeeType();
}
// Forbid the lambda copy-capture of autoreleasing variables.
if (CaptureType.getObjCLifetime() == Qualifiers::OCL_Autoreleasing) {
if (BuildAndDiagnose) {
S.Diag(Loc, diag::err_arc_autoreleasing_capture) << /*lambda*/ 1;
S.Diag(Var->getLocation(), diag::note_previous_decl)
<< Var->getDeclName();
}
return false;
}
// Make sure that by-copy captures are of a complete and non-abstract type.
if (BuildAndDiagnose) {
if (!CaptureType->isDependentType() &&
S.RequireCompleteType(Loc, CaptureType,
diag::err_capture_of_incomplete_type,
Var->getDeclName()))
return false;
if (S.RequireNonAbstractType(Loc, CaptureType,
diag::err_capture_of_abstract_type))
return false;
}
}
// Capture this variable in the lambda.
if (BuildAndDiagnose)
addAsFieldToClosureType(S, LSI, CaptureType, DeclRefType, Loc,
RefersToCapturedVariable);
// Compute the type of a reference to this captured variable.
if (ByRef)
DeclRefType = CaptureType.getNonReferenceType();
else {
// C++ [expr.prim.lambda]p5:
// The closure type for a lambda-expression has a public inline
// function call operator [...]. This function call operator is
// declared const (9.3.1) if and only if the lambda-expression's
// parameter-declaration-clause is not followed by mutable.
DeclRefType = CaptureType.getNonReferenceType();
if (!LSI->Mutable && !CaptureType->isReferenceType())
DeclRefType.addConst();
}
// Add the capture.
if (BuildAndDiagnose)
LSI->addCapture(Var, /*IsBlock=*/false, ByRef, RefersToCapturedVariable,
Loc, EllipsisLoc, CaptureType, /*CopyExpr=*/nullptr);
return true;
}
bool Sema::tryCaptureVariable(
VarDecl *Var, SourceLocation ExprLoc, TryCaptureKind Kind,
SourceLocation EllipsisLoc, bool BuildAndDiagnose, QualType &CaptureType,
QualType &DeclRefType, const unsigned *const FunctionScopeIndexToStopAt) {
// An init-capture is notionally from the context surrounding its
// declaration, but its parent DC is the lambda class.
DeclContext *VarDC = Var->getDeclContext();
if (Var->isInitCapture())
VarDC = VarDC->getParent();
DeclContext *DC = CurContext;
const unsigned MaxFunctionScopesIndex = FunctionScopeIndexToStopAt
? *FunctionScopeIndexToStopAt : FunctionScopes.size() - 1;
// We need to sync up the Declaration Context with the
// FunctionScopeIndexToStopAt
if (FunctionScopeIndexToStopAt) {
unsigned FSIndex = FunctionScopes.size() - 1;
while (FSIndex != MaxFunctionScopesIndex) {
DC = getLambdaAwareParentOfDeclContext(DC);
--FSIndex;
}
}
// If the variable is declared in the current context, there is no need to
// capture it.
if (VarDC == DC) return true;
// Capture global variables if it is required to use private copy of this
// variable.
bool IsGlobal = !Var->hasLocalStorage();
if (IsGlobal && !(LangOpts.OpenMP && isOpenMPCapturedDecl(Var)))
return true;
Var = Var->getCanonicalDecl();
// Walk up the stack to determine whether we can capture the variable,
// performing the "simple" checks that don't depend on type. We stop when
// we've either hit the declared scope of the variable or find an existing
// capture of that variable. We start from the innermost capturing-entity
// (the DC) and ensure that all intervening capturing-entities
// (blocks/lambdas etc.) between the innermost capturer and the variable`s
// declcontext can either capture the variable or have already captured
// the variable.
CaptureType = Var->getType();
DeclRefType = CaptureType.getNonReferenceType();
bool Nested = false;
bool Explicit = (Kind != TryCapture_Implicit);
unsigned FunctionScopesIndex = MaxFunctionScopesIndex;
do {
// Only block literals, captured statements, and lambda expressions can
// capture; other scopes don't work.
DeclContext *ParentDC = getParentOfCapturingContextOrNull(DC, Var,
ExprLoc,
BuildAndDiagnose,
*this);
// We need to check for the parent *first* because, if we *have*
// private-captured a global variable, we need to recursively capture it in
// intermediate blocks, lambdas, etc.
if (!ParentDC) {
if (IsGlobal) {
FunctionScopesIndex = MaxFunctionScopesIndex - 1;
break;
}
return true;
}
FunctionScopeInfo *FSI = FunctionScopes[FunctionScopesIndex];
CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FSI);
// Check whether we've already captured it.
if (isVariableAlreadyCapturedInScopeInfo(CSI, Var, Nested, CaptureType,
DeclRefType)) {
CSI->getCapture(Var).markUsed(BuildAndDiagnose);
break;
}
// If we are instantiating a generic lambda call operator body,
// we do not want to capture new variables. What was captured
// during either a lambdas transformation or initial parsing
// should be used.
if (isGenericLambdaCallOperatorSpecialization(DC)) {
if (BuildAndDiagnose) {
LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(CSI);
if (LSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None) {
Diag(ExprLoc, diag::err_lambda_impcap) << Var->getDeclName();
Diag(Var->getLocation(), diag::note_previous_decl)
<< Var->getDeclName();
Diag(LSI->Lambda->getLocStart(), diag::note_lambda_decl);
} else
diagnoseUncapturableValueReference(*this, ExprLoc, Var, DC);
}
return true;
}
// Certain capturing entities (lambdas, blocks etc.) are not allowed to capture
// certain types of variables (unnamed, variably modified types etc.)
// so check for eligibility.
if (!isVariableCapturable(CSI, Var, ExprLoc, BuildAndDiagnose, *this))
return true;
// Try to capture variable-length arrays types.
if (Var->getType()->isVariablyModifiedType()) {
// We're going to walk down into the type and look for VLA
// expressions.
QualType QTy = Var->getType();
if (ParmVarDecl *PVD = dyn_cast_or_null<ParmVarDecl>(Var))
QTy = PVD->getOriginalType();
captureVariablyModifiedType(Context, QTy, CSI);
}
if (getLangOpts().OpenMP) {
if (auto *RSI = dyn_cast<CapturedRegionScopeInfo>(CSI)) {
// OpenMP private variables should not be captured in outer scope, so
// just break here. Similarly, global variables that are captured in a
// target region should not be captured outside the scope of the region.
if (RSI->CapRegionKind == CR_OpenMP) {
bool IsOpenMPPrivateDecl = isOpenMPPrivateDecl(Var, RSI->OpenMPLevel);
auto IsTargetCap = !IsOpenMPPrivateDecl &&
isOpenMPTargetCapturedDecl(Var, RSI->OpenMPLevel);
// When we detect target captures we are looking from inside the
// target region, therefore we need to propagate the capture from the
// enclosing region. Therefore, the capture is not initially nested.
if (IsTargetCap)
adjustOpenMPTargetScopeIndex(FunctionScopesIndex, RSI->OpenMPLevel);
if (IsTargetCap || IsOpenMPPrivateDecl) {
Nested = !IsTargetCap;
DeclRefType = DeclRefType.getUnqualifiedType();
CaptureType = Context.getLValueReferenceType(DeclRefType);
break;
}
}
}
}
if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_None && !Explicit) {
// No capture-default, and this is not an explicit capture
// so cannot capture this variable.
if (BuildAndDiagnose) {
Diag(ExprLoc, diag::err_lambda_impcap) << Var->getDeclName();
Diag(Var->getLocation(), diag::note_previous_decl)
<< Var->getDeclName();
if (cast<LambdaScopeInfo>(CSI)->Lambda)
Diag(cast<LambdaScopeInfo>(CSI)->Lambda->getLocStart(),
diag::note_lambda_decl);
// FIXME: If we error out because an outer lambda can not implicitly
// capture a variable that an inner lambda explicitly captures, we
// should have the inner lambda do the explicit capture - because
// it makes for cleaner diagnostics later. This would purely be done
// so that the diagnostic does not misleadingly claim that a variable
// can not be captured by a lambda implicitly even though it is captured
// explicitly. Suggestion:
// - create const bool VariableCaptureWasInitiallyExplicit = Explicit
// at the function head
// - cache the StartingDeclContext - this must be a lambda
// - captureInLambda in the innermost lambda the variable.
}
return true;
}
FunctionScopesIndex--;
DC = ParentDC;
Explicit = false;
} while (!VarDC->Equals(DC));
// Walk back down the scope stack, (e.g. from outer lambda to inner lambda)
// computing the type of the capture at each step, checking type-specific
// requirements, and adding captures if requested.
// If the variable had already been captured previously, we start capturing
// at the lambda nested within that one.
for (unsigned I = ++FunctionScopesIndex, N = MaxFunctionScopesIndex + 1; I != N;
++I) {
CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[I]);
if (BlockScopeInfo *BSI = dyn_cast<BlockScopeInfo>(CSI)) {
if (!captureInBlock(BSI, Var, ExprLoc,
BuildAndDiagnose, CaptureType,
DeclRefType, Nested, *this))
return true;
Nested = true;
} else if (CapturedRegionScopeInfo *RSI = dyn_cast<CapturedRegionScopeInfo>(CSI)) {
if (!captureInCapturedRegion(RSI, Var, ExprLoc,
BuildAndDiagnose, CaptureType,
DeclRefType, Nested, *this))
return true;
Nested = true;
} else {
LambdaScopeInfo *LSI = cast<LambdaScopeInfo>(CSI);
if (!captureInLambda(LSI, Var, ExprLoc,
BuildAndDiagnose, CaptureType,
DeclRefType, Nested, Kind, EllipsisLoc,
/*IsTopScope*/I == N - 1, *this))
return true;
Nested = true;
}
}
return false;
}
bool Sema::tryCaptureVariable(VarDecl *Var, SourceLocation Loc,
TryCaptureKind Kind, SourceLocation EllipsisLoc) {
QualType CaptureType;
QualType DeclRefType;
return tryCaptureVariable(Var, Loc, Kind, EllipsisLoc,
/*BuildAndDiagnose=*/true, CaptureType,
DeclRefType, nullptr);
}
bool Sema::NeedToCaptureVariable(VarDecl *Var, SourceLocation Loc) {
QualType CaptureType;
QualType DeclRefType;
return !tryCaptureVariable(Var, Loc, TryCapture_Implicit, SourceLocation(),
/*BuildAndDiagnose=*/false, CaptureType,
DeclRefType, nullptr);
}
QualType Sema::getCapturedDeclRefType(VarDecl *Var, SourceLocation Loc) {
QualType CaptureType;
QualType DeclRefType;
// Determine whether we can capture this variable.
if (tryCaptureVariable(Var, Loc, TryCapture_Implicit, SourceLocation(),
/*BuildAndDiagnose=*/false, CaptureType,
DeclRefType, nullptr))
return QualType();
return DeclRefType;
}
// If either the type of the variable or the initializer is dependent,
// return false. Otherwise, determine whether the variable is a constant
// expression. Use this if you need to know if a variable that might or
// might not be dependent is truly a constant expression.
static inline bool IsVariableNonDependentAndAConstantExpression(VarDecl *Var,
ASTContext &Context) {
if (Var->getType()->isDependentType())
return false;
const VarDecl *DefVD = nullptr;
Var->getAnyInitializer(DefVD);
if (!DefVD)
return false;
EvaluatedStmt *Eval = DefVD->ensureEvaluatedStmt();
Expr *Init = cast<Expr>(Eval->Value);
if (Init->isValueDependent())
return false;
return IsVariableAConstantExpression(Var, Context);
}
void Sema::UpdateMarkingForLValueToRValue(Expr *E) {
// Per C++11 [basic.def.odr], a variable is odr-used "unless it is
// an object that satisfies the requirements for appearing in a
// constant expression (5.19) and the lvalue-to-rvalue conversion (4.1)
// is immediately applied." This function handles the lvalue-to-rvalue
// conversion part.
MaybeODRUseExprs.erase(E->IgnoreParens());
// If we are in a lambda, check if this DeclRefExpr or MemberExpr refers
// to a variable that is a constant expression, and if so, identify it as
// a reference to a variable that does not involve an odr-use of that
// variable.
if (LambdaScopeInfo *LSI = getCurLambda()) {
Expr *SansParensExpr = E->IgnoreParens();
VarDecl *Var = nullptr;
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(SansParensExpr))
Var = dyn_cast<VarDecl>(DRE->getFoundDecl());
else if (MemberExpr *ME = dyn_cast<MemberExpr>(SansParensExpr))
Var = dyn_cast<VarDecl>(ME->getMemberDecl());
if (Var && IsVariableNonDependentAndAConstantExpression(Var, Context))
LSI->markVariableExprAsNonODRUsed(SansParensExpr);
}
}
ExprResult Sema::ActOnConstantExpression(ExprResult Res) {
Res = CorrectDelayedTyposInExpr(Res);
if (!Res.isUsable())
return Res;
// If a constant-expression is a reference to a variable where we delay
// deciding whether it is an odr-use, just assume we will apply the
// lvalue-to-rvalue conversion. In the one case where this doesn't happen
// (a non-type template argument), we have special handling anyway.
UpdateMarkingForLValueToRValue(Res.get());
return Res;
}
void Sema::CleanupVarDeclMarking() {
for (Expr *E : MaybeODRUseExprs) {
VarDecl *Var;
SourceLocation Loc;
if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E)) {
Var = cast<VarDecl>(DRE->getDecl());
Loc = DRE->getLocation();
} else if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
Var = cast<VarDecl>(ME->getMemberDecl());
Loc = ME->getMemberLoc();
} else {
llvm_unreachable("Unexpected expression");
}
MarkVarDeclODRUsed(Var, Loc, *this,
/*MaxFunctionScopeIndex Pointer*/ nullptr);
}
MaybeODRUseExprs.clear();
}
static void DoMarkVarDeclReferenced(Sema &SemaRef, SourceLocation Loc,
VarDecl *Var, Expr *E) {
assert((!E || isa<DeclRefExpr>(E) || isa<MemberExpr>(E)) &&
"Invalid Expr argument to DoMarkVarDeclReferenced");
Var->setReferenced();
TemplateSpecializationKind TSK = Var->getTemplateSpecializationKind();
bool OdrUseContext = isOdrUseContext(SemaRef);
bool UsableInConstantExpr =
Var->isUsableInConstantExpressions(SemaRef.Context);
bool NeedDefinition =
OdrUseContext || (isEvaluatableContext(SemaRef) && UsableInConstantExpr);
VarTemplateSpecializationDecl *VarSpec =
dyn_cast<VarTemplateSpecializationDecl>(Var);
assert(!isa<VarTemplatePartialSpecializationDecl>(Var) &&
"Can't instantiate a partial template specialization.");
// If this might be a member specialization of a static data member, check
// the specialization is visible. We already did the checks for variable
// template specializations when we created them.
if (NeedDefinition && TSK != TSK_Undeclared &&
!isa<VarTemplateSpecializationDecl>(Var))
SemaRef.checkSpecializationVisibility(Loc, Var);
// Perform implicit instantiation of static data members, static data member
// templates of class templates, and variable template specializations. Delay
// instantiations of variable templates, except for those that could be used
// in a constant expression.
if (NeedDefinition && isTemplateInstantiation(TSK)) {
// Per C++17 [temp.explicit]p10, we may instantiate despite an explicit
// instantiation declaration if a variable is usable in a constant
// expression (among other cases).
bool TryInstantiating =
TSK == TSK_ImplicitInstantiation ||
(TSK == TSK_ExplicitInstantiationDeclaration && UsableInConstantExpr);
if (TryInstantiating) {
SourceLocation PointOfInstantiation = Var->getPointOfInstantiation();
bool FirstInstantiation = PointOfInstantiation.isInvalid();
if (FirstInstantiation) {
PointOfInstantiation = Loc;
Var->setTemplateSpecializationKind(TSK, PointOfInstantiation);
}
bool InstantiationDependent = false;
bool IsNonDependent =
VarSpec ? !TemplateSpecializationType::anyDependentTemplateArguments(
VarSpec->getTemplateArgsInfo(), InstantiationDependent)
: true;
// Do not instantiate specializations that are still type-dependent.
if (IsNonDependent) {
if (UsableInConstantExpr) {
// Do not defer instantiations of variables that could be used in a
// constant expression.
SemaRef.InstantiateVariableDefinition(PointOfInstantiation, Var);
} else if (FirstInstantiation ||
isa<VarTemplateSpecializationDecl>(Var)) {
// FIXME: For a specialization of a variable template, we don't
// distinguish between "declaration and type implicitly instantiated"
// and "implicit instantiation of definition requested", so we have
// no direct way to avoid enqueueing the pending instantiation
// multiple times.
SemaRef.PendingInstantiations
.push_back(std::make_pair(Var, PointOfInstantiation));
}
}
}
}
// Per C++11 [basic.def.odr], a variable is odr-used "unless it satisfies
// the requirements for appearing in a constant expression (5.19) and, if
// it is an object, the lvalue-to-rvalue conversion (4.1)
// is immediately applied." We check the first part here, and
// Sema::UpdateMarkingForLValueToRValue deals with the second part.
// Note that we use the C++11 definition everywhere because nothing in
// C++03 depends on whether we get the C++03 version correct. The second
// part does not apply to references, since they are not objects.
if (OdrUseContext && E &&
IsVariableAConstantExpression(Var, SemaRef.Context)) {
// A reference initialized by a constant expression can never be
// odr-used, so simply ignore it.
if (!Var->getType()->isReferenceType() ||
(SemaRef.LangOpts.OpenMP && SemaRef.isOpenMPCapturedDecl(Var)))
SemaRef.MaybeODRUseExprs.insert(E);
} else if (OdrUseContext) {
MarkVarDeclODRUsed(Var, Loc, SemaRef,
/*MaxFunctionScopeIndex ptr*/ nullptr);
} else if (isOdrUseContext(SemaRef, /*SkipDependentUses*/false)) {
// If this is a dependent context, we don't need to mark variables as
// odr-used, but we may still need to track them for lambda capture.
// FIXME: Do we also need to do this inside dependent typeid expressions
// (which are modeled as unevaluated at this point)?
const bool RefersToEnclosingScope =
(SemaRef.CurContext != Var->getDeclContext() &&
Var->getDeclContext()->isFunctionOrMethod() && Var->hasLocalStorage());
if (RefersToEnclosingScope) {
LambdaScopeInfo *const LSI =
SemaRef.getCurLambda(/*IgnoreNonLambdaCapturingScope=*/true);
if (LSI && (!LSI->CallOperator ||
!LSI->CallOperator->Encloses(Var->getDeclContext()))) {
// If a variable could potentially be odr-used, defer marking it so
// until we finish analyzing the full expression for any
// lvalue-to-rvalue
// or discarded value conversions that would obviate odr-use.
// Add it to the list of potential captures that will be analyzed
// later (ActOnFinishFullExpr) for eventual capture and odr-use marking
// unless the variable is a reference that was initialized by a constant
// expression (this will never need to be captured or odr-used).
assert(E && "Capture variable should be used in an expression.");
if (!Var->getType()->isReferenceType() ||
!IsVariableNonDependentAndAConstantExpression(Var, SemaRef.Context))
LSI->addPotentialCapture(E->IgnoreParens());
}
}
}
}
/// Mark a variable referenced, and check whether it is odr-used
/// (C++ [basic.def.odr]p2, C99 6.9p3). Note that this should not be
/// used directly for normal expressions referring to VarDecl.
void Sema::MarkVariableReferenced(SourceLocation Loc, VarDecl *Var) {
DoMarkVarDeclReferenced(*this, Loc, Var, nullptr);
}
static void MarkExprReferenced(Sema &SemaRef, SourceLocation Loc,
Decl *D, Expr *E, bool MightBeOdrUse) {
if (SemaRef.isInOpenMPDeclareTargetContext())
SemaRef.checkDeclIsAllowedInOpenMPTarget(E, D);
if (VarDecl *Var = dyn_cast<VarDecl>(D)) {
DoMarkVarDeclReferenced(SemaRef, Loc, Var, E);
return;
}
SemaRef.MarkAnyDeclReferenced(Loc, D, MightBeOdrUse);
// If this is a call to a method via a cast, also mark the method in the
// derived class used in case codegen can devirtualize the call.
const MemberExpr *ME = dyn_cast<MemberExpr>(E);
if (!ME)
return;
CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ME->getMemberDecl());
if (!MD)
return;
// Only attempt to devirtualize if this is truly a virtual call.
bool IsVirtualCall = MD->isVirtual() &&
ME->performsVirtualDispatch(SemaRef.getLangOpts());
if (!IsVirtualCall)
return;
// If it's possible to devirtualize the call, mark the called function
// referenced.
CXXMethodDecl *DM = MD->getDevirtualizedMethod(
ME->getBase(), SemaRef.getLangOpts().AppleKext);
if (DM)
SemaRef.MarkAnyDeclReferenced(Loc, DM, MightBeOdrUse);
}
/// Perform reference-marking and odr-use handling for a DeclRefExpr.
void Sema::MarkDeclRefReferenced(DeclRefExpr *E, const Expr *Base) {
// TODO: update this with DR# once a defect report is filed.
// C++11 defect. The address of a pure member should not be an ODR use, even
// if it's a qualified reference.
bool OdrUse = true;
if (const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(E->getDecl()))
if (Method->isVirtual() &&
!Method->getDevirtualizedMethod(Base, getLangOpts().AppleKext))
OdrUse = false;
MarkExprReferenced(*this, E->getLocation(), E->getDecl(), E, OdrUse);
}
/// Perform reference-marking and odr-use handling for a MemberExpr.
void Sema::MarkMemberReferenced(MemberExpr *E) {
// C++11 [basic.def.odr]p2:
// A non-overloaded function whose name appears as a potentially-evaluated
// expression or a member of a set of candidate functions, if selected by
// overload resolution when referred to from a potentially-evaluated
// expression, is odr-used, unless it is a pure virtual function and its
// name is not explicitly qualified.
bool MightBeOdrUse = true;
if (E->performsVirtualDispatch(getLangOpts())) {
if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(E->getMemberDecl()))
if (Method->isPure())
MightBeOdrUse = false;
}
SourceLocation Loc = E->getMemberLoc().isValid() ?
E->getMemberLoc() : E->getLocStart();
MarkExprReferenced(*this, Loc, E->getMemberDecl(), E, MightBeOdrUse);
}
/// Perform marking for a reference to an arbitrary declaration. It
/// marks the declaration referenced, and performs odr-use checking for
/// functions and variables. This method should not be used when building a
/// normal expression which refers to a variable.
void Sema::MarkAnyDeclReferenced(SourceLocation Loc, Decl *D,
bool MightBeOdrUse) {
if (MightBeOdrUse) {
if (auto *VD = dyn_cast<VarDecl>(D)) {
MarkVariableReferenced(Loc, VD);
return;
}
}
if (auto *FD = dyn_cast<FunctionDecl>(D)) {
MarkFunctionReferenced(Loc, FD, MightBeOdrUse);
return;
}
D->setReferenced();
}
namespace {
// Mark all of the declarations used by a type as referenced.
// FIXME: Not fully implemented yet! We need to have a better understanding
// of when we're entering a context we should not recurse into.
// FIXME: This is and EvaluatedExprMarker are more-or-less equivalent to
// TreeTransforms rebuilding the type in a new context. Rather than
// duplicating the TreeTransform logic, we should consider reusing it here.
// Currently that causes problems when rebuilding LambdaExprs.
class MarkReferencedDecls : public RecursiveASTVisitor<MarkReferencedDecls> {
Sema &S;
SourceLocation Loc;
public:
typedef RecursiveASTVisitor<MarkReferencedDecls> Inherited;
MarkReferencedDecls(Sema &S, SourceLocation Loc) : S(S), Loc(Loc) { }
bool TraverseTemplateArgument(const TemplateArgument &Arg);
};
}
bool MarkReferencedDecls::TraverseTemplateArgument(
const TemplateArgument &Arg) {
{
// A non-type template argument is a constant-evaluated context.
EnterExpressionEvaluationContext Evaluated(
S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
if (Arg.getKind() == TemplateArgument::Declaration) {
if (Decl *D = Arg.getAsDecl())
S.MarkAnyDeclReferenced(Loc, D, true);
} else if (Arg.getKind() == TemplateArgument::Expression) {
S.MarkDeclarationsReferencedInExpr(Arg.getAsExpr(), false);
}
}
return Inherited::TraverseTemplateArgument(Arg);
}
void Sema::MarkDeclarationsReferencedInType(SourceLocation Loc, QualType T) {
MarkReferencedDecls Marker(*this, Loc);
Marker.TraverseType(T);
}
namespace {
/// Helper class that marks all of the declarations referenced by
/// potentially-evaluated subexpressions as "referenced".
class EvaluatedExprMarker : public EvaluatedExprVisitor<EvaluatedExprMarker> {
Sema &S;
bool SkipLocalVariables;
public:
typedef EvaluatedExprVisitor<EvaluatedExprMarker> Inherited;
EvaluatedExprMarker(Sema &S, bool SkipLocalVariables)
: Inherited(S.Context), S(S), SkipLocalVariables(SkipLocalVariables) { }
void VisitDeclRefExpr(DeclRefExpr *E) {
// If we were asked not to visit local variables, don't.
if (SkipLocalVariables) {
if (VarDecl *VD = dyn_cast<VarDecl>(E->getDecl()))
if (VD->hasLocalStorage())
return;
}
S.MarkDeclRefReferenced(E);
}
void VisitMemberExpr(MemberExpr *E) {
S.MarkMemberReferenced(E);
Inherited::VisitMemberExpr(E);
}
void VisitCXXBindTemporaryExpr(CXXBindTemporaryExpr *E) {
S.MarkFunctionReferenced(E->getLocStart(),
const_cast<CXXDestructorDecl*>(E->getTemporary()->getDestructor()));
Visit(E->getSubExpr());
}
void VisitCXXNewExpr(CXXNewExpr *E) {
if (E->getOperatorNew())
S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorNew());
if (E->getOperatorDelete())
S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorDelete());
Inherited::VisitCXXNewExpr(E);
}
void VisitCXXDeleteExpr(CXXDeleteExpr *E) {
if (E->getOperatorDelete())
S.MarkFunctionReferenced(E->getLocStart(), E->getOperatorDelete());
QualType Destroyed = S.Context.getBaseElementType(E->getDestroyedType());
if (const RecordType *DestroyedRec = Destroyed->getAs<RecordType>()) {
CXXRecordDecl *Record = cast<CXXRecordDecl>(DestroyedRec->getDecl());
S.MarkFunctionReferenced(E->getLocStart(),
S.LookupDestructor(Record));
}
Inherited::VisitCXXDeleteExpr(E);
}
void VisitCXXConstructExpr(CXXConstructExpr *E) {
S.MarkFunctionReferenced(E->getLocStart(), E->getConstructor());
Inherited::VisitCXXConstructExpr(E);
}
void VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) {
Visit(E->getExpr());
}
void VisitImplicitCastExpr(ImplicitCastExpr *E) {
Inherited::VisitImplicitCastExpr(E);
if (E->getCastKind() == CK_LValueToRValue)
S.UpdateMarkingForLValueToRValue(E->getSubExpr());
}
};
}
/// Mark any declarations that appear within this expression or any
/// potentially-evaluated subexpressions as "referenced".
///
/// \param SkipLocalVariables If true, don't mark local variables as
/// 'referenced'.
void Sema::MarkDeclarationsReferencedInExpr(Expr *E,
bool SkipLocalVariables) {
EvaluatedExprMarker(*this, SkipLocalVariables).Visit(E);
}
/// Emit a diagnostic that describes an effect on the run-time behavior
/// of the program being compiled.
///
/// This routine emits the given diagnostic when the code currently being
/// type-checked is "potentially evaluated", meaning that there is a
/// possibility that the code will actually be executable. Code in sizeof()
/// expressions, code used only during overload resolution, etc., are not
/// potentially evaluated. This routine will suppress such diagnostics or,
/// in the absolutely nutty case of potentially potentially evaluated
/// expressions (C++ typeid), queue the diagnostic to potentially emit it
/// later.
///
/// This routine should be used for all diagnostics that describe the run-time
/// behavior of a program, such as passing a non-POD value through an ellipsis.
/// Failure to do so will likely result in spurious diagnostics or failures
/// during overload resolution or within sizeof/alignof/typeof/typeid.
bool Sema::DiagRuntimeBehavior(SourceLocation Loc, const Stmt *Statement,
const PartialDiagnostic &PD) {
switch (ExprEvalContexts.back().Context) {
case ExpressionEvaluationContext::Unevaluated:
case ExpressionEvaluationContext::UnevaluatedList:
case ExpressionEvaluationContext::UnevaluatedAbstract:
case ExpressionEvaluationContext::DiscardedStatement:
// The argument will never be evaluated, so don't complain.
break;
case ExpressionEvaluationContext::ConstantEvaluated:
// Relevant diagnostics should be produced by constant evaluation.
break;
case ExpressionEvaluationContext::PotentiallyEvaluated:
case ExpressionEvaluationContext::PotentiallyEvaluatedIfUsed:
if (Statement && getCurFunctionOrMethodDecl()) {
FunctionScopes.back()->PossiblyUnreachableDiags.
push_back(sema::PossiblyUnreachableDiag(PD, Loc, Statement));
return true;
}
// The initializer of a constexpr variable or of the first declaration of a
// static data member is not syntactically a constant evaluated constant,
// but nonetheless is always required to be a constant expression, so we
// can skip diagnosing.
// FIXME: Using the mangling context here is a hack.
if (auto *VD = dyn_cast_or_null<VarDecl>(
ExprEvalContexts.back().ManglingContextDecl)) {
if (VD->isConstexpr() ||
(VD->isStaticDataMember() && VD->isFirstDecl() && !VD->isInline()))
break;
// FIXME: For any other kind of variable, we should build a CFG for its
// initializer and check whether the context in question is reachable.
}
Diag(Loc, PD);
return true;
}
return false;
}
bool Sema::CheckCallReturnType(QualType ReturnType, SourceLocation Loc,
CallExpr *CE, FunctionDecl *FD) {
if (ReturnType->isVoidType() || !ReturnType->isIncompleteType())
return false;
// If we're inside a decltype's expression, don't check for a valid return
// type or construct temporaries until we know whether this is the last call.
if (ExprEvalContexts.back().ExprContext ==
ExpressionEvaluationContextRecord::EK_Decltype) {
ExprEvalContexts.back().DelayedDecltypeCalls.push_back(CE);
return false;
}
class CallReturnIncompleteDiagnoser : public TypeDiagnoser {
FunctionDecl *FD;
CallExpr *CE;
public:
CallReturnIncompleteDiagnoser(FunctionDecl *FD, CallExpr *CE)
: FD(FD), CE(CE) { }
void diagnose(Sema &S, SourceLocation Loc, QualType T) override {
if (!FD) {
S.Diag(Loc, diag::err_call_incomplete_return)
<< T << CE->getSourceRange();
return;
}
S.Diag(Loc, diag::err_call_function_incomplete_return)
<< CE->getSourceRange() << FD->getDeclName() << T;
S.Diag(FD->getLocation(), diag::note_entity_declared_at)
<< FD->getDeclName();
}
} Diagnoser(FD, CE);
if (RequireCompleteType(Loc, ReturnType, Diagnoser))
return true;
return false;
}
// Diagnose the s/=/==/ and s/\|=/!=/ typos. Note that adding parentheses
// will prevent this condition from triggering, which is what we want.
void Sema::DiagnoseAssignmentAsCondition(Expr *E) {
SourceLocation Loc;
unsigned diagnostic = diag::warn_condition_is_assignment;
bool IsOrAssign = false;
if (BinaryOperator *Op = dyn_cast<BinaryOperator>(E)) {
if (Op->getOpcode() != BO_Assign && Op->getOpcode() != BO_OrAssign)
return;
IsOrAssign = Op->getOpcode() == BO_OrAssign;
// Greylist some idioms by putting them into a warning subcategory.
if (ObjCMessageExpr *ME
= dyn_cast<ObjCMessageExpr>(Op->getRHS()->IgnoreParenCasts())) {
Selector Sel = ME->getSelector();
// self = [<foo> init...]
if (isSelfExpr(Op->getLHS()) && ME->getMethodFamily() == OMF_init)
diagnostic = diag::warn_condition_is_idiomatic_assignment;
// <foo> = [<bar> nextObject]
else if (Sel.isUnarySelector() && Sel.getNameForSlot(0) == "nextObject")
diagnostic = diag::warn_condition_is_idiomatic_assignment;
}
Loc = Op->getOperatorLoc();
} else if (CXXOperatorCallExpr *Op = dyn_cast<CXXOperatorCallExpr>(E)) {
if (Op->getOperator() != OO_Equal && Op->getOperator() != OO_PipeEqual)
return;
IsOrAssign = Op->getOperator() == OO_PipeEqual;
Loc = Op->getOperatorLoc();
} else if (PseudoObjectExpr *POE = dyn_cast<PseudoObjectExpr>(E))
return DiagnoseAssignmentAsCondition(POE->getSyntacticForm());
else {
// Not an assignment.
return;
}
Diag(Loc, diagnostic) << E->getSourceRange();
SourceLocation Open = E->getLocStart();
SourceLocation Close = getLocForEndOfToken(E->getSourceRange().getEnd());
Diag(Loc, diag::note_condition_assign_silence)
<< FixItHint::CreateInsertion(Open, "(")
<< FixItHint::CreateInsertion(Close, ")");
if (IsOrAssign)
Diag(Loc, diag::note_condition_or_assign_to_comparison)
<< FixItHint::CreateReplacement(Loc, "!=");
else
Diag(Loc, diag::note_condition_assign_to_comparison)
<< FixItHint::CreateReplacement(Loc, "==");
}
/// Redundant parentheses over an equality comparison can indicate
/// that the user intended an assignment used as condition.
void Sema::DiagnoseEqualityWithExtraParens(ParenExpr *ParenE) {
// Don't warn if the parens came from a macro.
SourceLocation parenLoc = ParenE->getLocStart();
if (parenLoc.isInvalid() || parenLoc.isMacroID())
return;
// Don't warn for dependent expressions.
if (ParenE->isTypeDependent())
return;
Expr *E = ParenE->IgnoreParens();
if (BinaryOperator *opE = dyn_cast<BinaryOperator>(E))
if (opE->getOpcode() == BO_EQ &&
opE->getLHS()->IgnoreParenImpCasts()->isModifiableLvalue(Context)
== Expr::MLV_Valid) {
SourceLocation Loc = opE->getOperatorLoc();
Diag(Loc, diag::warn_equality_with_extra_parens) << E->getSourceRange();
SourceRange ParenERange = ParenE->getSourceRange();
Diag(Loc, diag::note_equality_comparison_silence)
<< FixItHint::CreateRemoval(ParenERange.getBegin())
<< FixItHint::CreateRemoval(ParenERange.getEnd());
Diag(Loc, diag::note_equality_comparison_to_assign)
<< FixItHint::CreateReplacement(Loc, "=");
}
}
ExprResult Sema::CheckBooleanCondition(SourceLocation Loc, Expr *E,
bool IsConstexpr) {
DiagnoseAssignmentAsCondition(E);
if (ParenExpr *parenE = dyn_cast<ParenExpr>(E))
DiagnoseEqualityWithExtraParens(parenE);
ExprResult result = CheckPlaceholderExpr(E);
if (result.isInvalid()) return ExprError();
E = result.get();
if (!E->isTypeDependent()) {
if (getLangOpts().CPlusPlus)
return CheckCXXBooleanCondition(E, IsConstexpr); // C++ 6.4p4
ExprResult ERes = DefaultFunctionArrayLvalueConversion(E);
if (ERes.isInvalid())
return ExprError();
E = ERes.get();
QualType T = E->getType();
if (!T->isScalarType()) { // C99 6.8.4.1p1
Diag(Loc, diag::err_typecheck_statement_requires_scalar)
<< T << E->getSourceRange();
return ExprError();
}
CheckBoolLikeConversion(E, Loc);
}
return E;
}
Sema::ConditionResult Sema::ActOnCondition(Scope *S, SourceLocation Loc,
Expr *SubExpr, ConditionKind CK) {
// Empty conditions are valid in for-statements.
if (!SubExpr)
return ConditionResult();
ExprResult Cond;
switch (CK) {
case ConditionKind::Boolean:
Cond = CheckBooleanCondition(Loc, SubExpr);
break;
case ConditionKind::ConstexprIf:
Cond = CheckBooleanCondition(Loc, SubExpr, true);
break;
case ConditionKind::Switch:
Cond = CheckSwitchCondition(Loc, SubExpr);
break;
}
if (Cond.isInvalid())
return ConditionError();
// FIXME: FullExprArg doesn't have an invalid bit, so check nullness instead.
FullExprArg FullExpr = MakeFullExpr(Cond.get(), Loc);
if (!FullExpr.get())
return ConditionError();
return ConditionResult(*this, nullptr, FullExpr,
CK == ConditionKind::ConstexprIf);
}
namespace {
/// A visitor for rebuilding a call to an __unknown_any expression
/// to have an appropriate type.
struct RebuildUnknownAnyFunction
: StmtVisitor<RebuildUnknownAnyFunction, ExprResult> {
Sema &S;
RebuildUnknownAnyFunction(Sema &S) : S(S) {}
ExprResult VisitStmt(Stmt *S) {
llvm_unreachable("unexpected statement!");
}
ExprResult VisitExpr(Expr *E) {
S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_call)
<< E->getSourceRange();
return ExprError();
}
/// Rebuild an expression which simply semantically wraps another
/// expression which it shares the type and value kind of.
template <class T> ExprResult rebuildSugarExpr(T *E) {
ExprResult SubResult = Visit(E->getSubExpr());
if (SubResult.isInvalid()) return ExprError();
Expr *SubExpr = SubResult.get();
E->setSubExpr(SubExpr);
E->setType(SubExpr->getType());
E->setValueKind(SubExpr->getValueKind());
assert(E->getObjectKind() == OK_Ordinary);
return E;
}
ExprResult VisitParenExpr(ParenExpr *E) {
return rebuildSugarExpr(E);
}
ExprResult VisitUnaryExtension(UnaryOperator *E) {
return rebuildSugarExpr(E);
}
ExprResult VisitUnaryAddrOf(UnaryOperator *E) {
ExprResult SubResult = Visit(E->getSubExpr());
if (SubResult.isInvalid()) return ExprError();
Expr *SubExpr = SubResult.get();
E->setSubExpr(SubExpr);
E->setType(S.Context.getPointerType(SubExpr->getType()));
assert(E->getValueKind() == VK_RValue);
assert(E->getObjectKind() == OK_Ordinary);
return E;
}
ExprResult resolveDecl(Expr *E, ValueDecl *VD) {
if (!isa<FunctionDecl>(VD)) return VisitExpr(E);
E->setType(VD->getType());
assert(E->getValueKind() == VK_RValue);
if (S.getLangOpts().CPlusPlus &&
!(isa<CXXMethodDecl>(VD) &&
cast<CXXMethodDecl>(VD)->isInstance()))
E->setValueKind(VK_LValue);
return E;
}
ExprResult VisitMemberExpr(MemberExpr *E) {
return resolveDecl(E, E->getMemberDecl());
}
ExprResult VisitDeclRefExpr(DeclRefExpr *E) {
return resolveDecl(E, E->getDecl());
}
};
}
/// Given a function expression of unknown-any type, try to rebuild it
/// to have a function type.
static ExprResult rebuildUnknownAnyFunction(Sema &S, Expr *FunctionExpr) {
ExprResult Result = RebuildUnknownAnyFunction(S).Visit(FunctionExpr);
if (Result.isInvalid()) return ExprError();
return S.DefaultFunctionArrayConversion(Result.get());
}
namespace {
/// A visitor for rebuilding an expression of type __unknown_anytype
/// into one which resolves the type directly on the referring
/// expression. Strict preservation of the original source
/// structure is not a goal.
struct RebuildUnknownAnyExpr
: StmtVisitor<RebuildUnknownAnyExpr, ExprResult> {
Sema &S;
/// The current destination type.
QualType DestType;
RebuildUnknownAnyExpr(Sema &S, QualType CastType)
: S(S), DestType(CastType) {}
ExprResult VisitStmt(Stmt *S) {
llvm_unreachable("unexpected statement!");
}
ExprResult VisitExpr(Expr *E) {
S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr)
<< E->getSourceRange();
return ExprError();
}
ExprResult VisitCallExpr(CallExpr *E);
ExprResult VisitObjCMessageExpr(ObjCMessageExpr *E);
/// Rebuild an expression which simply semantically wraps another
/// expression which it shares the type and value kind of.
template <class T> ExprResult rebuildSugarExpr(T *E) {
ExprResult SubResult = Visit(E->getSubExpr());
if (SubResult.isInvalid()) return ExprError();
Expr *SubExpr = SubResult.get();
E->setSubExpr(SubExpr);
E->setType(SubExpr->getType());
E->setValueKind(SubExpr->getValueKind());
assert(E->getObjectKind() == OK_Ordinary);
return E;
}
ExprResult VisitParenExpr(ParenExpr *E) {
return rebuildSugarExpr(E);
}
ExprResult VisitUnaryExtension(UnaryOperator *E) {
return rebuildSugarExpr(E);
}
ExprResult VisitUnaryAddrOf(UnaryOperator *E) {
const PointerType *Ptr = DestType->getAs<PointerType>();
if (!Ptr) {
S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof)
<< E->getSourceRange();
return ExprError();
}
if (isa<CallExpr>(E->getSubExpr())) {
S.Diag(E->getOperatorLoc(), diag::err_unknown_any_addrof_call)
<< E->getSourceRange();
return ExprError();
}
assert(E->getValueKind() == VK_RValue);
assert(E->getObjectKind() == OK_Ordinary);
E->setType(DestType);
// Build the sub-expression as if it were an object of the pointee type.
DestType = Ptr->getPointeeType();
ExprResult SubResult = Visit(E->getSubExpr());
if (SubResult.isInvalid()) return ExprError();
E->setSubExpr(SubResult.get());
return E;
}
ExprResult VisitImplicitCastExpr(ImplicitCastExpr *E);
ExprResult resolveDecl(Expr *E, ValueDecl *VD);
ExprResult VisitMemberExpr(MemberExpr *E) {
return resolveDecl(E, E->getMemberDecl());
}
ExprResult VisitDeclRefExpr(DeclRefExpr *E) {
return resolveDecl(E, E->getDecl());
}
};
}
/// Rebuilds a call expression which yielded __unknown_anytype.
ExprResult RebuildUnknownAnyExpr::VisitCallExpr(CallExpr *E) {
Expr *CalleeExpr = E->getCallee();
enum FnKind {
FK_MemberFunction,
FK_FunctionPointer,
FK_BlockPointer
};
FnKind Kind;
QualType CalleeType = CalleeExpr->getType();
if (CalleeType == S.Context.BoundMemberTy) {
assert(isa<CXXMemberCallExpr>(E) || isa<CXXOperatorCallExpr>(E));
Kind = FK_MemberFunction;
CalleeType = Expr::findBoundMemberType(CalleeExpr);
} else if (const PointerType *Ptr = CalleeType->getAs<PointerType>()) {
CalleeType = Ptr->getPointeeType();
Kind = FK_FunctionPointer;
} else {
CalleeType = CalleeType->castAs<BlockPointerType>()->getPointeeType();
Kind = FK_BlockPointer;
}
const FunctionType *FnType = CalleeType->castAs<FunctionType>();
// Verify that this is a legal result type of a function.
if (DestType->isArrayType() || DestType->isFunctionType()) {
unsigned diagID = diag::err_func_returning_array_function;
if (Kind == FK_BlockPointer)
diagID = diag::err_block_returning_array_function;
S.Diag(E->getExprLoc(), diagID)
<< DestType->isFunctionType() << DestType;
return ExprError();
}
// Otherwise, go ahead and set DestType as the call's result.
E->setType(DestType.getNonLValueExprType(S.Context));
E->setValueKind(Expr::getValueKindForType(DestType));
assert(E->getObjectKind() == OK_Ordinary);
// Rebuild the function type, replacing the result type with DestType.
const FunctionProtoType *Proto = dyn_cast<FunctionProtoType>(FnType);
if (Proto) {
// __unknown_anytype(...) is a special case used by the debugger when
// it has no idea what a function's signature is.
//
// We want to build this call essentially under the K&R
// unprototyped rules, but making a FunctionNoProtoType in C++
// would foul up all sorts of assumptions. However, we cannot
// simply pass all arguments as variadic arguments, nor can we
// portably just call the function under a non-variadic type; see
// the comment on IR-gen's TargetInfo::isNoProtoCallVariadic.
// However, it turns out that in practice it is generally safe to
// call a function declared as "A foo(B,C,D);" under the prototype
// "A foo(B,C,D,...);". The only known exception is with the
// Windows ABI, where any variadic function is implicitly cdecl
// regardless of its normal CC. Therefore we change the parameter
// types to match the types of the arguments.
//
// This is a hack, but it is far superior to moving the
// corresponding target-specific code from IR-gen to Sema/AST.
ArrayRef<QualType> ParamTypes = Proto->getParamTypes();
SmallVector<QualType, 8> ArgTypes;
if (ParamTypes.empty() && Proto->isVariadic()) { // the special case
ArgTypes.reserve(E->getNumArgs());
for (unsigned i = 0, e = E->getNumArgs(); i != e; ++i) {
Expr *Arg = E->getArg(i);
QualType ArgType = Arg->getType();
if (E->isLValue()) {
ArgType = S.Context.getLValueReferenceType(ArgType);
} else if (E->isXValue()) {
ArgType = S.Context.getRValueReferenceType(ArgType);
}
ArgTypes.push_back(ArgType);
}
ParamTypes = ArgTypes;
}
DestType = S.Context.getFunctionType(DestType, ParamTypes,
Proto->getExtProtoInfo());
} else {
DestType = S.Context.getFunctionNoProtoType(DestType,
FnType->getExtInfo());
}
// Rebuild the appropriate pointer-to-function type.
switch (Kind) {
case FK_MemberFunction:
// Nothing to do.
break;
case FK_FunctionPointer:
DestType = S.Context.getPointerType(DestType);
break;
case FK_BlockPointer:
DestType = S.Context.getBlockPointerType(DestType);
break;
}
// Finally, we can recurse.
ExprResult CalleeResult = Visit(CalleeExpr);
if (!CalleeResult.isUsable()) return ExprError();
E->setCallee(CalleeResult.get());
// Bind a temporary if necessary.
return S.MaybeBindToTemporary(E);
}
ExprResult RebuildUnknownAnyExpr::VisitObjCMessageExpr(ObjCMessageExpr *E) {
// Verify that this is a legal result type of a call.
if (DestType->isArrayType() || DestType->isFunctionType()) {
S.Diag(E->getExprLoc(), diag::err_func_returning_array_function)
<< DestType->isFunctionType() << DestType;
return ExprError();
}
// Rewrite the method result type if available.
if (ObjCMethodDecl *Method = E->getMethodDecl()) {
assert(Method->getReturnType() == S.Context.UnknownAnyTy);
Method->setReturnType(DestType);
}
// Change the type of the message.
E->setType(DestType.getNonReferenceType());
E->setValueKind(Expr::getValueKindForType(DestType));
return S.MaybeBindToTemporary(E);
}
ExprResult RebuildUnknownAnyExpr::VisitImplicitCastExpr(ImplicitCastExpr *E) {
// The only case we should ever see here is a function-to-pointer decay.
if (E->getCastKind() == CK_FunctionToPointerDecay) {
assert(E->getValueKind() == VK_RValue);
assert(E->getObjectKind() == OK_Ordinary);
E->setType(DestType);
// Rebuild the sub-expression as the pointee (function) type.
DestType = DestType->castAs<PointerType>()->getPointeeType();
ExprResult Result = Visit(E->getSubExpr());
if (!Result.isUsable()) return ExprError();
E->setSubExpr(Result.get());
return E;
} else if (E->getCastKind() == CK_LValueToRValue) {
assert(E->getValueKind() == VK_RValue);
assert(E->getObjectKind() == OK_Ordinary);
assert(isa<BlockPointerType>(E->getType()));
E->setType(DestType);
// The sub-expression has to be a lvalue reference, so rebuild it as such.
DestType = S.Context.getLValueReferenceType(DestType);
ExprResult Result = Visit(E->getSubExpr());
if (!Result.isUsable()) return ExprError();
E->setSubExpr(Result.get());
return E;
} else {
llvm_unreachable("Unhandled cast type!");
}
}
ExprResult RebuildUnknownAnyExpr::resolveDecl(Expr *E, ValueDecl *VD) {
ExprValueKind ValueKind = VK_LValue;
QualType Type = DestType;
// We know how to make this work for certain kinds of decls:
// - functions
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(VD)) {
if (const PointerType *Ptr = Type->getAs<PointerType>()) {
DestType = Ptr->getPointeeType();
ExprResult Result = resolveDecl(E, VD);
if (Result.isInvalid()) return ExprError();
return S.ImpCastExprToType(Result.get(), Type,
CK_FunctionToPointerDecay, VK_RValue);
}
if (!Type->isFunctionType()) {
S.Diag(E->getExprLoc(), diag::err_unknown_any_function)
<< VD << E->getSourceRange();
return ExprError();
}
if (const FunctionProtoType *FT = Type->getAs<FunctionProtoType>()) {
// We must match the FunctionDecl's type to the hack introduced in
// RebuildUnknownAnyExpr::VisitCallExpr to vararg functions of unknown
// type. See the lengthy commentary in that routine.
QualType FDT = FD->getType();
const FunctionType *FnType = FDT->castAs<FunctionType>();
const FunctionProtoType *Proto = dyn_cast_or_null<FunctionProtoType>(FnType);
DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E);
if (DRE && Proto && Proto->getParamTypes().empty() && Proto->isVariadic()) {
SourceLocation Loc = FD->getLocation();
FunctionDecl *NewFD = FunctionDecl::Create(FD->getASTContext(),
FD->getDeclContext(),
Loc, Loc, FD->getNameInfo().getName(),
DestType, FD->getTypeSourceInfo(),
SC_None, false/*isInlineSpecified*/,
FD->hasPrototype(),
false/*isConstexprSpecified*/);
if (FD->getQualifier())
NewFD->setQualifierInfo(FD->getQualifierLoc());
SmallVector<ParmVarDecl*, 16> Params;
for (const auto &AI : FT->param_types()) {
ParmVarDecl *Param =
S.BuildParmVarDeclForTypedef(FD, Loc, AI);
Param->setScopeInfo(0, Params.size());
Params.push_back(Param);
}
NewFD->setParams(Params);
DRE->setDecl(NewFD);
VD = DRE->getDecl();
}
}
if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD))
if (MD->isInstance()) {
ValueKind = VK_RValue;
Type = S.Context.BoundMemberTy;
}
// Function references aren't l-values in C.
if (!S.getLangOpts().CPlusPlus)
ValueKind = VK_RValue;
// - variables
} else if (isa<VarDecl>(VD)) {
if (const ReferenceType *RefTy = Type->getAs<ReferenceType>()) {
Type = RefTy->getPointeeType();
} else if (Type->isFunctionType()) {
S.Diag(E->getExprLoc(), diag::err_unknown_any_var_function_type)
<< VD << E->getSourceRange();
return ExprError();
}
// - nothing else
} else {
S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_decl)
<< VD << E->getSourceRange();
return ExprError();
}
// Modifying the declaration like this is friendly to IR-gen but
// also really dangerous.
VD->setType(DestType);
E->setType(Type);
E->setValueKind(ValueKind);
return E;
}
/// Check a cast of an unknown-any type. We intentionally only
/// trigger this for C-style casts.
ExprResult Sema::checkUnknownAnyCast(SourceRange TypeRange, QualType CastType,
Expr *CastExpr, CastKind &CastKind,
ExprValueKind &VK, CXXCastPath &Path) {
// The type we're casting to must be either void or complete.
if (!CastType->isVoidType() &&
RequireCompleteType(TypeRange.getBegin(), CastType,
diag::err_typecheck_cast_to_incomplete))
return ExprError();
// Rewrite the casted expression from scratch.
ExprResult result = RebuildUnknownAnyExpr(*this, CastType).Visit(CastExpr);
if (!result.isUsable()) return ExprError();
CastExpr = result.get();
VK = CastExpr->getValueKind();
CastKind = CK_NoOp;
return CastExpr;
}
ExprResult Sema::forceUnknownAnyToType(Expr *E, QualType ToType) {
return RebuildUnknownAnyExpr(*this, ToType).Visit(E);
}
ExprResult Sema::checkUnknownAnyArg(SourceLocation callLoc,
Expr *arg, QualType &paramType) {
// If the syntactic form of the argument is not an explicit cast of
// any sort, just do default argument promotion.
ExplicitCastExpr *castArg = dyn_cast<ExplicitCastExpr>(arg->IgnoreParens());
if (!castArg) {
ExprResult result = DefaultArgumentPromotion(arg);
if (result.isInvalid()) return ExprError();
paramType = result.get()->getType();
return result;
}
// Otherwise, use the type that was written in the explicit cast.
assert(!arg->hasPlaceholderType());
paramType = castArg->getTypeAsWritten();
// Copy-initialize a parameter of that type.
InitializedEntity entity =
InitializedEntity::InitializeParameter(Context, paramType,
/*consumed*/ false);
return PerformCopyInitialization(entity, callLoc, arg);
}
static ExprResult diagnoseUnknownAnyExpr(Sema &S, Expr *E) {
Expr *orig = E;
unsigned diagID = diag::err_uncasted_use_of_unknown_any;
while (true) {
E = E->IgnoreParenImpCasts();
if (CallExpr *call = dyn_cast<CallExpr>(E)) {
E = call->getCallee();
diagID = diag::err_uncasted_call_of_unknown_any;
} else {
break;
}
}
SourceLocation loc;
NamedDecl *d;
if (DeclRefExpr *ref = dyn_cast<DeclRefExpr>(E)) {
loc = ref->getLocation();
d = ref->getDecl();
} else if (MemberExpr *mem = dyn_cast<MemberExpr>(E)) {
loc = mem->getMemberLoc();
d = mem->getMemberDecl();
} else if (ObjCMessageExpr *msg = dyn_cast<ObjCMessageExpr>(E)) {
diagID = diag::err_uncasted_call_of_unknown_any;
loc = msg->getSelectorStartLoc();
d = msg->getMethodDecl();
if (!d) {
S.Diag(loc, diag::err_uncasted_send_to_unknown_any_method)
<< static_cast<unsigned>(msg->isClassMessage()) << msg->getSelector()
<< orig->getSourceRange();
return ExprError();
}
} else {
S.Diag(E->getExprLoc(), diag::err_unsupported_unknown_any_expr)
<< E->getSourceRange();
return ExprError();
}
S.Diag(loc, diagID) << d << orig->getSourceRange();
// Never recoverable.
return ExprError();
}
/// Check for operands with placeholder types and complain if found.
/// Returns ExprError() if there was an error and no recovery was possible.
ExprResult Sema::CheckPlaceholderExpr(Expr *E) {
if (!getLangOpts().CPlusPlus) {
// C cannot handle TypoExpr nodes on either side of a binop because it
// doesn't handle dependent types properly, so make sure any TypoExprs have
// been dealt with before checking the operands.
ExprResult Result = CorrectDelayedTyposInExpr(E);
if (!Result.isUsable()) return ExprError();
E = Result.get();
}
const BuiltinType *placeholderType = E->getType()->getAsPlaceholderType();
if (!placeholderType) return E;
switch (placeholderType->getKind()) {
// Overloaded expressions.
case BuiltinType::Overload: {
// Try to resolve a single function template specialization.
// This is obligatory.
ExprResult Result = E;
if (ResolveAndFixSingleFunctionTemplateSpecialization(Result, false))
return Result;
// No guarantees that ResolveAndFixSingleFunctionTemplateSpecialization
// leaves Result unchanged on failure.
Result = E;
if (resolveAndFixAddressOfOnlyViableOverloadCandidate(Result))
return Result;
// If that failed, try to recover with a call.
tryToRecoverWithCall(Result, PDiag(diag::err_ovl_unresolvable),
/*complain*/ true);
return Result;
}
// Bound member functions.
case BuiltinType::BoundMember: {
ExprResult result = E;
const Expr *BME = E->IgnoreParens();
PartialDiagnostic PD = PDiag(diag::err_bound_member_function);
// Try to give a nicer diagnostic if it is a bound member that we recognize.
if (isa<CXXPseudoDestructorExpr>(BME)) {
PD = PDiag(diag::err_dtor_expr_without_call) << /*pseudo-destructor*/ 1;
} else if (const auto *ME = dyn_cast<MemberExpr>(BME)) {
if (ME->getMemberNameInfo().getName().getNameKind() ==
DeclarationName::CXXDestructorName)
PD = PDiag(diag::err_dtor_expr_without_call) << /*destructor*/ 0;
}
tryToRecoverWithCall(result, PD,
/*complain*/ true);
return result;
}
// ARC unbridged casts.
case BuiltinType::ARCUnbridgedCast: {
Expr *realCast = stripARCUnbridgedCast(E);
diagnoseARCUnbridgedCast(realCast);
return realCast;
}
// Expressions of unknown type.
case BuiltinType::UnknownAny:
return diagnoseUnknownAnyExpr(*this, E);
// Pseudo-objects.
case BuiltinType::PseudoObject:
return checkPseudoObjectRValue(E);
case BuiltinType::BuiltinFn: {
// Accept __noop without parens by implicitly converting it to a call expr.
auto *DRE = dyn_cast<DeclRefExpr>(E->IgnoreParenImpCasts());
if (DRE) {
auto *FD = cast<FunctionDecl>(DRE->getDecl());
if (FD->getBuiltinID() == Builtin::BI__noop) {
E = ImpCastExprToType(E, Context.getPointerType(FD->getType()),
CK_BuiltinFnToFnPtr).get();
return new (Context) CallExpr(Context, E, None, Context.IntTy,
VK_RValue, SourceLocation());
}
}
Diag(E->getLocStart(), diag::err_builtin_fn_use);
return ExprError();
}
// Expressions of unknown type.
case BuiltinType::OMPArraySection:
Diag(E->getLocStart(), diag::err_omp_array_section_use);
return ExprError();
// Everything else should be impossible.
#define IMAGE_TYPE(ImgType, Id, SingletonId, Access, Suffix) \
case BuiltinType::Id:
#include "clang/Basic/OpenCLImageTypes.def"
#define BUILTIN_TYPE(Id, SingletonId) case BuiltinType::Id:
#define PLACEHOLDER_TYPE(Id, SingletonId)
#include "clang/AST/BuiltinTypes.def"
break;
}
llvm_unreachable("invalid placeholder type!");
}
bool Sema::CheckCaseExpression(Expr *E) {
if (E->isTypeDependent())
return true;
if (E->isValueDependent() || E->isIntegerConstantExpr(Context))
return E->getType()->isIntegralOrEnumerationType();
return false;
}
/// ActOnObjCBoolLiteral - Parse {__objc_yes,__objc_no} literals.
ExprResult
Sema::ActOnObjCBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
assert((Kind == tok::kw___objc_yes || Kind == tok::kw___objc_no) &&
"Unknown Objective-C Boolean value!");
QualType BoolT = Context.ObjCBuiltinBoolTy;
if (!Context.getBOOLDecl()) {
LookupResult Result(*this, &Context.Idents.get("BOOL"), OpLoc,
Sema::LookupOrdinaryName);
if (LookupName(Result, getCurScope()) && Result.isSingleResult()) {
NamedDecl *ND = Result.getFoundDecl();
if (TypedefDecl *TD = dyn_cast<TypedefDecl>(ND))
Context.setBOOLDecl(TD);
}
}
if (Context.getBOOLDecl())
BoolT = Context.getBOOLType();
return new (Context)
ObjCBoolLiteralExpr(Kind == tok::kw___objc_yes, BoolT, OpLoc);
}
ExprResult Sema::ActOnObjCAvailabilityCheckExpr(
llvm::ArrayRef<AvailabilitySpec> AvailSpecs, SourceLocation AtLoc,
SourceLocation RParen) {
StringRef Platform = getASTContext().getTargetInfo().getPlatformName();
auto Spec = std::find_if(AvailSpecs.begin(), AvailSpecs.end(),
[&](const AvailabilitySpec &Spec) {
return Spec.getPlatform() == Platform;
});
VersionTuple Version;
if (Spec != AvailSpecs.end())
Version = Spec->getVersion();
// The use of `@available` in the enclosing function should be analyzed to
// warn when it's used inappropriately (i.e. not if(@available)).
if (getCurFunctionOrMethodDecl())
getEnclosingFunction()->HasPotentialAvailabilityViolations = true;
else if (getCurBlock() || getCurLambda())
getCurFunction()->HasPotentialAvailabilityViolations = true;
return new (Context)
ObjCAvailabilityCheckExpr(Version, AtLoc, RParen, Context.BoolTy);
}