Import Cobalt 19.master.0.203780

Includes the following patches:
  https://cobalt-review.googlesource.com/c/cobalt/+/5210
    by errong.leng@samsung.com
  https://cobalt-review.googlesource.com/c/cobalt/+/5270
    by linus.wang@samsung.com
diff --git a/src/third_party/llvm-project/libcxx/include/__config b/src/third_party/llvm-project/libcxx/include/__config
new file mode 100644
index 0000000..738d891
--- /dev/null
+++ b/src/third_party/llvm-project/libcxx/include/__config
@@ -0,0 +1,1376 @@
+// -*- C++ -*-
+//===--------------------------- __config ---------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is dual licensed under the MIT and the University of Illinois Open
+// Source Licenses. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef _LIBCPP_CONFIG
+#define _LIBCPP_CONFIG
+
+#if defined(_MSC_VER) && !defined(__clang__)
+#  if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
+#    define _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+#  endif
+#endif
+
+#ifndef _LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER
+#pragma GCC system_header
+#endif
+
+#ifdef __cplusplus
+
+#ifdef __GNUC__
+#  define _GNUC_VER (__GNUC__ * 100 + __GNUC_MINOR__)
+// The _GNUC_VER_NEW macro better represents the new GCC versioning scheme
+// introduced in GCC 5.0.
+#  define _GNUC_VER_NEW (_GNUC_VER * 10 + __GNUC_PATCHLEVEL__)
+#else
+#  define _GNUC_VER 0
+#  define _GNUC_VER_NEW 0
+#endif
+
+#define _LIBCPP_VERSION 7000
+
+#ifndef _LIBCPP_ABI_VERSION
+#  ifdef __Fuchsia__
+#    define _LIBCPP_ABI_VERSION 2
+#  else
+#    define _LIBCPP_ABI_VERSION 1
+#  endif
+#endif
+
+#ifndef _LIBCPP_STD_VER
+#  if  __cplusplus <= 201103L
+#    define _LIBCPP_STD_VER 11
+#  elif __cplusplus <= 201402L
+#    define _LIBCPP_STD_VER 14
+#  elif __cplusplus <= 201703L
+#    define _LIBCPP_STD_VER 17
+#  else
+#    define _LIBCPP_STD_VER 18  // current year, or date of c++2a ratification
+#  endif
+#endif  // _LIBCPP_STD_VER
+
+#if defined(__ELF__)
+#  define _LIBCPP_OBJECT_FORMAT_ELF   1
+#elif defined(__MACH__)
+#  define _LIBCPP_OBJECT_FORMAT_MACHO 1
+#elif defined(_WIN32)
+#  define _LIBCPP_OBJECT_FORMAT_COFF  1
+#elif defined(__wasm__)
+#  define _LIBCPP_OBJECT_FORMAT_WASM  1
+#else
+#  error Unknown object file format
+#endif
+
+#if defined(_LIBCPP_ABI_UNSTABLE) || _LIBCPP_ABI_VERSION >= 2
+// Change short string representation so that string data starts at offset 0,
+// improving its alignment in some cases.
+#  define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
+// Fix deque iterator type in order to support incomplete types.
+#  define _LIBCPP_ABI_INCOMPLETE_TYPES_IN_DEQUE
+// Fix undefined behavior in how std::list stores its linked nodes.
+#  define _LIBCPP_ABI_LIST_REMOVE_NODE_POINTER_UB
+// Fix undefined behavior in  how __tree stores its end and parent nodes.
+#  define _LIBCPP_ABI_TREE_REMOVE_NODE_POINTER_UB
+// Fix undefined behavior in how __hash_table stores its pointer types.
+#  define _LIBCPP_ABI_FIX_UNORDERED_NODE_POINTER_UB
+#  define _LIBCPP_ABI_FORWARD_LIST_REMOVE_NODE_POINTER_UB
+#  define _LIBCPP_ABI_FIX_UNORDERED_CONTAINER_SIZE_TYPE
+// Don't use a nullptr_t simulation type in C++03 instead using C++11 nullptr
+// provided under the alternate keyword __nullptr, which changes the mangling
+// of nullptr_t. This option is ABI incompatible with GCC in C++03 mode.
+#  define _LIBCPP_ABI_ALWAYS_USE_CXX11_NULLPTR
+// Define the `pointer_safety` enum as a C++11 strongly typed enumeration
+// instead of as a class simulating an enum. If this option is enabled
+// `pointer_safety` and `get_pointer_safety()` will no longer be available
+// in C++03.
+#  define _LIBCPP_ABI_POINTER_SAFETY_ENUM_TYPE
+// Define a key function for `bad_function_call` in the library, to centralize
+// its vtable and typeinfo to libc++ rather than having all other libraries
+// using that class define their own copies.
+#  define _LIBCPP_ABI_BAD_FUNCTION_CALL_KEY_FUNCTION
+// Enable optimized version of __do_get_(un)signed which avoids redundant copies.
+#  define _LIBCPP_ABI_OPTIMIZED_LOCALE_NUM_GET
+// Use the smallest possible integer type to represent the index of the variant.
+// Previously libc++ used "unsigned int" exclusivly.
+#  define _LIBCPP_ABI_VARIANT_INDEX_TYPE_OPTIMIZATION
+#elif _LIBCPP_ABI_VERSION == 1
+#  if !defined(_LIBCPP_OBJECT_FORMAT_COFF)
+// Enable compiling copies of now inline methods into the dylib to support
+// applications compiled against older libraries. This is unnecessary with
+// COFF dllexport semantics, since dllexport forces a non-inline definition
+// of inline functions to be emitted anyway. Our own non-inline copy would
+// conflict with the dllexport-emitted copy, so we disable it.
+#    define _LIBCPP_DEPRECATED_ABI_LEGACY_LIBRARY_DEFINITIONS_FOR_INLINE_FUNCTIONS
+#  endif
+// Feature macros for disabling pre ABI v1 features. All of these options
+// are deprecated.
+#  if defined(__FreeBSD__)
+#    define _LIBCPP_DEPRECATED_ABI_DISABLE_PAIR_TRIVIAL_COPY_CTOR
+#  endif
+#endif
+
+#ifdef _LIBCPP_TRIVIAL_PAIR_COPY_CTOR
+#error "_LIBCPP_TRIVIAL_PAIR_COPY_CTOR" is no longer supported. \
+       use _LIBCPP_DEPRECATED_ABI_DISABLE_PAIR_TRIVIAL_COPY_CTOR instead
+#endif
+
+#define _LIBCPP_CONCAT1(_LIBCPP_X,_LIBCPP_Y) _LIBCPP_X##_LIBCPP_Y
+#define _LIBCPP_CONCAT(_LIBCPP_X,_LIBCPP_Y) _LIBCPP_CONCAT1(_LIBCPP_X,_LIBCPP_Y)
+
+#define _LIBCPP_NAMESPACE _LIBCPP_CONCAT(__,_LIBCPP_ABI_VERSION)
+
+#if __cplusplus < 201103L
+#define _LIBCPP_CXX03_LANG
+#endif
+
+#ifndef __has_attribute
+#define __has_attribute(__x) 0
+#endif
+
+#ifndef __has_builtin
+#define __has_builtin(__x) 0
+#endif
+
+#ifndef __has_extension
+#define __has_extension(__x) 0
+#endif
+
+#ifndef __has_feature
+#define __has_feature(__x) 0
+#endif
+
+#ifndef __has_cpp_attribute
+#define __has_cpp_attribute(__x) 0
+#endif
+
+// '__is_identifier' returns '0' if '__x' is a reserved identifier provided by
+// the compiler and '1' otherwise.
+#ifndef __is_identifier
+#define __is_identifier(__x) 1
+#endif
+
+#ifndef __has_declspec_attribute
+#define __has_declspec_attribute(__x) 0
+#endif
+
+#define __has_keyword(__x) !(__is_identifier(__x))
+
+#ifndef __has_include
+#define __has_include(...) 0
+#endif
+
+#if defined(__clang__)
+#  define _LIBCPP_COMPILER_CLANG
+#  ifndef __apple_build_version__
+#    define _LIBCPP_CLANG_VER (__clang_major__ * 100 + __clang_minor__)
+#  endif
+#elif defined(__GNUC__)
+#  define _LIBCPP_COMPILER_GCC
+#elif defined(_MSC_VER)
+#  define _LIBCPP_COMPILER_MSVC
+#elif defined(__IBMCPP__)
+#  define _LIBCPP_COMPILER_IBM
+#endif
+
+#ifndef _LIBCPP_CLANG_VER
+#define _LIBCPP_CLANG_VER 0
+#endif
+
+// FIXME: ABI detection should be done via compiler builtin macros. This
+// is just a placeholder until Clang implements such macros. For now assume
+// that Windows compilers pretending to be MSVC++ target the Microsoft ABI,
+// and allow the user to explicitly specify the ABI to handle cases where this
+// heuristic falls short.
+#if defined(_LIBCPP_ABI_FORCE_ITANIUM) && defined(_LIBCPP_ABI_FORCE_MICROSOFT)
+#  error "Only one of _LIBCPP_ABI_FORCE_ITANIUM and _LIBCPP_ABI_FORCE_MICROSOFT can be defined"
+#elif defined(_LIBCPP_ABI_FORCE_ITANIUM)
+#  define _LIBCPP_ABI_ITANIUM
+#elif defined(_LIBCPP_ABI_FORCE_MICROSOFT)
+#  define _LIBCPP_ABI_MICROSOFT
+#else
+#  if defined(_WIN32) && defined(_MSC_VER)
+#    define _LIBCPP_ABI_MICROSOFT
+#  else
+#    define _LIBCPP_ABI_ITANIUM
+#  endif
+#endif
+
+// Need to detect which libc we're using if we're on Linux.
+#if defined(__linux__)
+#  include <features.h>
+#  if defined(__GLIBC_PREREQ)
+#    define _LIBCPP_GLIBC_PREREQ(a, b) __GLIBC_PREREQ(a, b)
+#  else
+#    define _LIBCPP_GLIBC_PREREQ(a, b) 0
+#  endif // defined(__GLIBC_PREREQ)
+#endif // defined(__linux__)
+
+#ifdef __LITTLE_ENDIAN__
+#  if __LITTLE_ENDIAN__
+#    define _LIBCPP_LITTLE_ENDIAN
+#  endif  // __LITTLE_ENDIAN__
+#endif  // __LITTLE_ENDIAN__
+
+#ifdef __BIG_ENDIAN__
+#  if __BIG_ENDIAN__
+#    define _LIBCPP_BIG_ENDIAN
+#  endif  // __BIG_ENDIAN__
+#endif  // __BIG_ENDIAN__
+
+#ifdef __BYTE_ORDER__
+#  if __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
+#    define _LIBCPP_LITTLE_ENDIAN
+#  elif __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#    define _LIBCPP_BIG_ENDIAN
+#  endif // __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__
+#endif // __BYTE_ORDER__
+
+#ifdef __FreeBSD__
+#  include <sys/endian.h>
+#  if _BYTE_ORDER == _LITTLE_ENDIAN
+#    define _LIBCPP_LITTLE_ENDIAN
+#  else  // _BYTE_ORDER == _LITTLE_ENDIAN
+#    define _LIBCPP_BIG_ENDIAN
+#  endif  // _BYTE_ORDER == _LITTLE_ENDIAN
+#  ifndef __LONG_LONG_SUPPORTED
+#    define _LIBCPP_HAS_NO_LONG_LONG
+#  endif  // __LONG_LONG_SUPPORTED
+#endif  // __FreeBSD__
+
+#ifdef __NetBSD__
+#  include <sys/endian.h>
+#  if _BYTE_ORDER == _LITTLE_ENDIAN
+#    define _LIBCPP_LITTLE_ENDIAN
+#  else  // _BYTE_ORDER == _LITTLE_ENDIAN
+#    define _LIBCPP_BIG_ENDIAN
+#  endif  // _BYTE_ORDER == _LITTLE_ENDIAN
+#  define _LIBCPP_HAS_QUICK_EXIT
+#endif  // __NetBSD__
+
+#if defined(_WIN32)
+#  define _LIBCPP_WIN32API
+#  define _LIBCPP_LITTLE_ENDIAN
+#  define _LIBCPP_SHORT_WCHAR   1
+// Both MinGW and native MSVC provide a "MSVC"-like enviroment
+#  define _LIBCPP_MSVCRT_LIKE
+// If mingw not explicitly detected, assume using MS C runtime only if
+// a MS compatibility version is specified.
+#  if defined(_MSC_VER) && !defined(__MINGW32__)
+#    define _LIBCPP_MSVCRT // Using Microsoft's C Runtime library
+#  endif
+#  if (defined(_M_AMD64) || defined(__x86_64__)) || (defined(_M_ARM) || defined(__arm__))
+#    define _LIBCPP_HAS_BITSCAN64
+#  endif
+#  define _LIBCPP_HAS_OPEN_WITH_WCHAR
+#  if defined(_LIBCPP_MSVCRT)
+#    define _LIBCPP_HAS_QUICK_EXIT
+#  endif
+
+// Some CRT APIs are unavailable to store apps
+#  if defined(WINAPI_FAMILY)
+#    include <winapifamily.h>
+#    if !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP) &&                  \
+        (!defined(WINAPI_PARTITION_SYSTEM) ||                                  \
+         !WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_SYSTEM))
+#      define _LIBCPP_WINDOWS_STORE_APP
+#    endif
+#  endif
+#endif // defined(_WIN32)
+
+#ifdef __sun__
+#  include <sys/isa_defs.h>
+#  ifdef _LITTLE_ENDIAN
+#    define _LIBCPP_LITTLE_ENDIAN
+#  else
+#    define _LIBCPP_BIG_ENDIAN
+#  endif
+#endif // __sun__
+
+#if defined(__CloudABI__)
+   // Certain architectures provide arc4random(). Prefer using
+   // arc4random() over /dev/{u,}random to make it possible to obtain
+   // random data even when using sandboxing mechanisms such as chroots,
+   // Capsicum, etc.
+#  define _LIBCPP_USING_ARC4_RANDOM
+#elif defined(__Fuchsia__)
+#  define _LIBCPP_USING_GETENTROPY
+#elif defined(__native_client__)
+   // NaCl's sandbox (which PNaCl also runs in) doesn't allow filesystem access,
+   // including accesses to the special files under /dev. C++11's
+   // std::random_device is instead exposed through a NaCl syscall.
+#  define _LIBCPP_USING_NACL_RANDOM
+#elif defined(_LIBCPP_WIN32API)
+#  define _LIBCPP_USING_WIN32_RANDOM
+#else
+#  define _LIBCPP_USING_DEV_RANDOM
+#endif
+
+#if !defined(_LIBCPP_LITTLE_ENDIAN) && !defined(_LIBCPP_BIG_ENDIAN)
+#  include <endian.h>
+#  if __BYTE_ORDER == __LITTLE_ENDIAN
+#    define _LIBCPP_LITTLE_ENDIAN
+#  elif __BYTE_ORDER == __BIG_ENDIAN
+#    define _LIBCPP_BIG_ENDIAN
+#  else  // __BYTE_ORDER == __BIG_ENDIAN
+#    error unable to determine endian
+#  endif
+#endif  // !defined(_LIBCPP_LITTLE_ENDIAN) && !defined(_LIBCPP_BIG_ENDIAN)
+
+#if __has_attribute(__no_sanitize__) && !defined(_LIBCPP_COMPILER_GCC)
+#  define _LIBCPP_NO_CFI __attribute__((__no_sanitize__("cfi")))
+#else
+#  define _LIBCPP_NO_CFI
+#endif
+
+#if __ISO_C_VISIBLE >= 2011 || __cplusplus >= 201103L
+#  if defined(__FreeBSD__)
+#    define _LIBCPP_HAS_QUICK_EXIT
+#    define _LIBCPP_HAS_C11_FEATURES
+#  elif defined(__Fuchsia__)
+#    define _LIBCPP_HAS_QUICK_EXIT
+#    define _LIBCPP_HAS_TIMESPEC_GET
+#    define _LIBCPP_HAS_C11_FEATURES
+#  elif defined(__linux__)
+#    if !defined(_LIBCPP_HAS_MUSL_LIBC)
+#      if _LIBCPP_GLIBC_PREREQ(2, 15) || defined(__BIONIC__)
+#        define _LIBCPP_HAS_QUICK_EXIT
+#      endif
+#      if _LIBCPP_GLIBC_PREREQ(2, 17)
+#        define _LIBCPP_HAS_C11_FEATURES
+#        define _LIBCPP_HAS_TIMESPEC_GET
+#      endif
+#    else // defined(_LIBCPP_HAS_MUSL_LIBC)
+#      define _LIBCPP_HAS_QUICK_EXIT
+#      define _LIBCPP_HAS_TIMESPEC_GET
+#      define _LIBCPP_HAS_C11_FEATURES
+#    endif
+#  endif // __linux__
+#endif
+
+#if defined(_LIBCPP_COMPILER_CLANG)
+
+// _LIBCPP_ALTERNATE_STRING_LAYOUT is an old name for
+// _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT left here for backward compatibility.
+#if (defined(__APPLE__) && !defined(__i386__) && !defined(__x86_64__) &&       \
+     (!defined(__arm__) || __ARM_ARCH_7K__ >= 2)) ||                           \
+    defined(_LIBCPP_ALTERNATE_STRING_LAYOUT)
+#define _LIBCPP_ABI_ALTERNATE_STRING_LAYOUT
+#endif
+
+#if __has_feature(cxx_alignas)
+#  define _ALIGNAS_TYPE(x) alignas(x)
+#  define _ALIGNAS(x) alignas(x)
+#else
+#  define _ALIGNAS_TYPE(x) __attribute__((__aligned__(__alignof(x))))
+#  define _ALIGNAS(x) __attribute__((__aligned__(x)))
+#endif
+
+#if __cplusplus < 201103L
+typedef __char16_t char16_t;
+typedef __char32_t char32_t;
+#endif
+
+#if !(__has_feature(cxx_exceptions)) && !defined(_LIBCPP_NO_EXCEPTIONS)
+#define _LIBCPP_NO_EXCEPTIONS
+#endif
+
+#if !(__has_feature(cxx_rtti)) && !defined(_LIBCPP_NO_RTTI)
+#define _LIBCPP_NO_RTTI
+#endif
+
+#if !(__has_feature(cxx_strong_enums))
+#define _LIBCPP_HAS_NO_STRONG_ENUMS
+#endif
+
+#if !(__has_feature(cxx_decltype))
+#define _LIBCPP_HAS_NO_DECLTYPE
+#endif
+
+#if __has_feature(cxx_attributes)
+#  define _LIBCPP_NORETURN [[noreturn]]
+#else
+#  define _LIBCPP_NORETURN __attribute__ ((noreturn))
+#endif
+
+#if !(__has_feature(cxx_lambdas))
+#define _LIBCPP_HAS_NO_LAMBDAS
+#endif
+
+#if !(__has_feature(cxx_nullptr))
+#  if (__has_extension(cxx_nullptr) || __has_keyword(__nullptr)) && defined(_LIBCPP_ABI_ALWAYS_USE_CXX11_NULLPTR)
+#    define nullptr __nullptr
+#  else
+#    define _LIBCPP_HAS_NO_NULLPTR
+#  endif
+#endif
+
+#if !(__has_feature(cxx_rvalue_references))
+#define _LIBCPP_HAS_NO_RVALUE_REFERENCES
+#endif
+
+#if !(__has_feature(cxx_auto_type))
+#define _LIBCPP_HAS_NO_AUTO_TYPE
+#endif
+
+#if !(__has_feature(cxx_variadic_templates))
+#define _LIBCPP_HAS_NO_VARIADICS
+#endif
+
+#if !(__has_feature(cxx_generalized_initializers))
+#define _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
+#endif
+
+#if __has_feature(is_base_of)
+#define _LIBCPP_HAS_IS_BASE_OF
+#endif
+
+#if __has_feature(is_final)
+#define _LIBCPP_HAS_IS_FINAL
+#endif
+
+// Objective-C++ features (opt-in)
+#if __has_feature(objc_arc)
+#define _LIBCPP_HAS_OBJC_ARC
+#endif
+
+#if __has_feature(objc_arc_weak)
+#define _LIBCPP_HAS_OBJC_ARC_WEAK
+#endif
+
+#if !(__has_feature(cxx_constexpr))
+#define _LIBCPP_HAS_NO_CONSTEXPR
+#endif
+
+#if !(__has_feature(cxx_relaxed_constexpr))
+#define _LIBCPP_HAS_NO_CXX14_CONSTEXPR
+#endif
+
+#if !(__has_feature(cxx_variable_templates))
+#define _LIBCPP_HAS_NO_VARIABLE_TEMPLATES
+#endif
+
+#if !(__has_feature(cxx_noexcept))
+#define _LIBCPP_HAS_NO_NOEXCEPT
+#endif
+
+#if __has_feature(underlying_type)
+#define _LIBCPP_UNDERLYING_TYPE(T) __underlying_type(T)
+#endif
+
+#if __has_feature(is_literal)
+#define _LIBCPP_IS_LITERAL(T) __is_literal(T)
+#endif
+
+// Inline namespaces are available in Clang regardless of C++ dialect.
+#define _LIBCPP_BEGIN_NAMESPACE_STD namespace std {inline namespace _LIBCPP_NAMESPACE {
+#define _LIBCPP_END_NAMESPACE_STD  } }
+#define _VSTD std::_LIBCPP_NAMESPACE
+
+namespace std {
+  inline namespace _LIBCPP_NAMESPACE {
+  }
+}
+
+#if !defined(_LIBCPP_HAS_NO_ASAN) && !__has_feature(address_sanitizer)
+#define _LIBCPP_HAS_NO_ASAN
+#endif
+
+// Allow for build-time disabling of unsigned integer sanitization
+#if !defined(_LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK) && __has_attribute(no_sanitize)
+#define _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK __attribute__((__no_sanitize__("unsigned-integer-overflow")))
+#endif
+
+#if __has_builtin(__builtin_launder)
+#define _LIBCPP_COMPILER_HAS_BUILTIN_LAUNDER
+#endif
+
+#if !__is_identifier(__has_unique_object_representations)
+#define _LIBCPP_HAS_UNIQUE_OBJECT_REPRESENTATIONS
+#endif
+
+#define _LIBCPP_ALWAYS_INLINE __attribute__ ((__always_inline__))
+
+#elif defined(_LIBCPP_COMPILER_GCC)
+
+#define _ALIGNAS(x) __attribute__((__aligned__(x)))
+#define _ALIGNAS_TYPE(x) __attribute__((__aligned__(__alignof(x))))
+
+#define _LIBCPP_NORETURN __attribute__((noreturn))
+
+#if _GNUC_VER >= 407
+#define _LIBCPP_UNDERLYING_TYPE(T) __underlying_type(T)
+#define _LIBCPP_IS_LITERAL(T) __is_literal_type(T)
+#define _LIBCPP_HAS_IS_FINAL
+#endif
+
+#if defined(__GNUC__) && _GNUC_VER >= 403
+#define _LIBCPP_HAS_IS_BASE_OF
+#endif
+
+#if !__EXCEPTIONS && !defined(_LIBCPP_NO_EXCEPTIONS)
+#define _LIBCPP_NO_EXCEPTIONS
+#endif
+
+// constexpr was added to GCC in 4.6.
+#if _GNUC_VER < 406
+#  define _LIBCPP_HAS_NO_CONSTEXPR
+// Can only use constexpr in c++11 mode.
+#elif !defined(__GXX_EXPERIMENTAL_CXX0X__) && __cplusplus < 201103L
+#  define _LIBCPP_HAS_NO_CONSTEXPR
+#endif
+
+// Determine if GCC supports relaxed constexpr
+#if !defined(__cpp_constexpr) || __cpp_constexpr < 201304L
+#define _LIBCPP_HAS_NO_CXX14_CONSTEXPR
+#endif
+
+// GCC 5 will support variable templates
+#if !defined(__cpp_variable_templates) || __cpp_variable_templates < 201304L
+#define _LIBCPP_HAS_NO_VARIABLE_TEMPLATES
+#endif
+
+#ifndef __GXX_EXPERIMENTAL_CXX0X__
+
+#define _LIBCPP_HAS_NO_DECLTYPE
+#define _LIBCPP_HAS_NO_NULLPTR
+#define _LIBCPP_HAS_NO_UNICODE_CHARS
+#define _LIBCPP_HAS_NO_VARIADICS
+#define _LIBCPP_HAS_NO_RVALUE_REFERENCES
+#define _LIBCPP_HAS_NO_STRONG_ENUMS
+#define _LIBCPP_HAS_NO_NOEXCEPT
+
+#else  // __GXX_EXPERIMENTAL_CXX0X__
+
+#if _GNUC_VER < 403
+#define _LIBCPP_HAS_NO_RVALUE_REFERENCES
+#endif
+
+
+#if _GNUC_VER < 404
+#define _LIBCPP_HAS_NO_DECLTYPE
+#define _LIBCPP_HAS_NO_UNICODE_CHARS
+#define _LIBCPP_HAS_NO_VARIADICS
+#define _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
+#endif  // _GNUC_VER < 404
+
+#if _GNUC_VER < 406
+#define _LIBCPP_HAS_NO_NOEXCEPT
+#define _LIBCPP_HAS_NO_NULLPTR
+#endif
+
+#endif  // __GXX_EXPERIMENTAL_CXX0X__
+
+#define _LIBCPP_BEGIN_NAMESPACE_STD namespace std { inline namespace _LIBCPP_NAMESPACE {
+#define _LIBCPP_END_NAMESPACE_STD  } }
+#define _VSTD std::_LIBCPP_NAMESPACE
+
+namespace std {
+  inline namespace _LIBCPP_NAMESPACE {
+  }
+}
+
+#if !defined(_LIBCPP_HAS_NO_ASAN) && !defined(__SANITIZE_ADDRESS__)
+#define _LIBCPP_HAS_NO_ASAN
+#endif
+
+#if _GNUC_VER >= 700
+#define _LIBCPP_COMPILER_HAS_BUILTIN_LAUNDER
+#endif
+
+#if _GNUC_VER >= 700
+#define _LIBCPP_HAS_UNIQUE_OBJECT_REPRESENTATIONS
+#endif
+
+#define _LIBCPP_ALWAYS_INLINE __attribute__ ((__always_inline__))
+
+#elif defined(_LIBCPP_COMPILER_MSVC)
+
+#define _LIBCPP_TOSTRING2(x) #x
+#define _LIBCPP_TOSTRING(x) _LIBCPP_TOSTRING2(x)
+#define _LIBCPP_WARNING(x) __pragma(message(__FILE__ "(" _LIBCPP_TOSTRING(__LINE__) ") : warning note: " x))
+
+#if _MSC_VER < 1900
+#error "MSVC versions prior to Visual Studio 2015 are not supported"
+#endif
+
+#define _LIBCPP_HAS_IS_BASE_OF
+#define _LIBCPP_HAS_NO_CONSTEXPR
+#define _LIBCPP_HAS_NO_CXX14_CONSTEXPR
+#define _LIBCPP_HAS_NO_VARIABLE_TEMPLATES
+#define _LIBCPP_HAS_NO_NOEXCEPT
+#define __alignof__ __alignof
+#define _LIBCPP_NORETURN __declspec(noreturn)
+#define _ALIGNAS(x) __declspec(align(x))
+#define _ALIGNAS_TYPE(x) alignas(x)
+#define _LIBCPP_HAS_NO_VARIADICS
+
+#define _LIBCPP_BEGIN_NAMESPACE_STD namespace std {
+#define _LIBCPP_END_NAMESPACE_STD  }
+#define _VSTD std
+
+namespace std {
+}
+
+#define _LIBCPP_WEAK
+
+#define _LIBCPP_HAS_NO_ASAN
+
+#define _LIBCPP_ALWAYS_INLINE __forceinline
+
+#define _LIBCPP_HAS_NO_VECTOR_EXTENSION
+
+#elif defined(_LIBCPP_COMPILER_IBM)
+
+#define _ALIGNAS(x) __attribute__((__aligned__(x)))
+#define _ALIGNAS_TYPE(x) __attribute__((__aligned__(__alignof(x))))
+#define _ATTRIBUTE(x) __attribute__((x))
+#define _LIBCPP_NORETURN __attribute__((noreturn))
+
+#define _LIBCPP_HAS_NO_GENERALIZED_INITIALIZERS
+#define _LIBCPP_HAS_NO_NOEXCEPT
+#define _LIBCPP_HAS_NO_NULLPTR
+#define _LIBCPP_HAS_NO_UNICODE_CHARS
+#define _LIBCPP_HAS_IS_BASE_OF
+#define _LIBCPP_HAS_IS_FINAL
+#define _LIBCPP_HAS_NO_VARIABLE_TEMPLATES
+
+#if defined(_AIX)
+#define __MULTILOCALE_API
+#endif
+
+#define _LIBCPP_BEGIN_NAMESPACE_STD namespace std {inline namespace _LIBCPP_NAMESPACE {
+#define _LIBCPP_END_NAMESPACE_STD  } }
+#define _VSTD std::_LIBCPP_NAMESPACE
+
+namespace std {
+  inline namespace _LIBCPP_NAMESPACE {
+  }
+}
+
+#define _LIBCPP_HAS_NO_ASAN
+
+#define _LIBCPP_ALWAYS_INLINE __attribute__ ((__always_inline__))
+
+#define _LIBCPP_HAS_NO_VECTOR_EXTENSION
+
+#endif // _LIBCPP_COMPILER_[CLANG|GCC|MSVC|IBM]
+
+#if _LIBCPP_STD_VER >= 17
+#define _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM \
+  _LIBCPP_BEGIN_NAMESPACE_STD inline namespace __fs { namespace filesystem {
+#else
+#define _LIBCPP_BEGIN_NAMESPACE_FILESYSTEM \
+  _LIBCPP_BEGIN_NAMESPACE_STD namespace __fs { namespace filesystem {
+#endif
+
+#define _LIBCPP_END_NAMESPACE_FILESYSTEM \
+  _LIBCPP_END_NAMESPACE_STD } }
+
+#define _VSTD_FS _VSTD::__fs::filesystem
+
+
+#if defined(_LIBCPP_OBJECT_FORMAT_COFF)
+
+#ifdef _DLL
+#  define _LIBCPP_CRT_FUNC __declspec(dllimport)
+#else
+#  define _LIBCPP_CRT_FUNC
+#endif
+
+#if defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+#  define _LIBCPP_DLL_VIS
+#  define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
+#  define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
+#  define _LIBCPP_OVERRIDABLE_FUNC_VIS
+#elif defined(_LIBCPP_BUILDING_LIBRARY)
+#  define _LIBCPP_DLL_VIS __declspec(dllexport)
+#  define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
+#  define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS _LIBCPP_DLL_VIS
+#  define _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_DLL_VIS
+#else
+#  define _LIBCPP_DLL_VIS __declspec(dllimport)
+#  define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS _LIBCPP_DLL_VIS
+#  define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
+#  define _LIBCPP_OVERRIDABLE_FUNC_VIS
+#endif
+
+#define _LIBCPP_TYPE_VIS            _LIBCPP_DLL_VIS
+#define _LIBCPP_FUNC_VIS            _LIBCPP_DLL_VIS
+#define _LIBCPP_EXTERN_VIS          _LIBCPP_DLL_VIS
+#define _LIBCPP_EXCEPTION_ABI       _LIBCPP_DLL_VIS
+#define _LIBCPP_HIDDEN
+#define _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
+#define _LIBCPP_TEMPLATE_VIS
+#define _LIBCPP_ENUM_VIS
+
+#if defined(_LIBCPP_COMPILER_MSVC)
+#  define _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY __forceinline
+#else
+#  define _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY __attribute__ ((__always_inline__))
+#endif
+
+#endif // defined(_LIBCPP_OBJECT_FORMAT_COFF)
+
+#ifndef _LIBCPP_HIDDEN
+#  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+#    define _LIBCPP_HIDDEN __attribute__ ((__visibility__("hidden")))
+#  else
+#    define _LIBCPP_HIDDEN
+#  endif
+#endif
+
+#ifndef _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
+#  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+// The inline should be removed once PR32114 is resolved
+#    define _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS inline _LIBCPP_HIDDEN
+#  else
+#    define _LIBCPP_METHOD_TEMPLATE_IMPLICIT_INSTANTIATION_VIS
+#  endif
+#endif
+
+#ifndef _LIBCPP_FUNC_VIS
+#  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+#    define _LIBCPP_FUNC_VIS __attribute__ ((__visibility__("default")))
+#  else
+#    define _LIBCPP_FUNC_VIS
+#  endif
+#endif
+
+#ifndef _LIBCPP_TYPE_VIS
+#  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+#    define _LIBCPP_TYPE_VIS __attribute__ ((__visibility__("default")))
+#  else
+#    define _LIBCPP_TYPE_VIS
+#  endif
+#endif
+
+#ifndef _LIBCPP_TEMPLATE_VIS
+#  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+#    if __has_attribute(__type_visibility__)
+#      define _LIBCPP_TEMPLATE_VIS __attribute__ ((__type_visibility__("default")))
+#    else
+#      define _LIBCPP_TEMPLATE_VIS __attribute__ ((__visibility__("default")))
+#    endif
+#  else
+#    define _LIBCPP_TEMPLATE_VIS
+#  endif
+#endif
+
+#ifndef _LIBCPP_EXTERN_VIS
+#define _LIBCPP_EXTERN_VIS
+#endif
+
+#ifndef _LIBCPP_OVERRIDABLE_FUNC_VIS
+#define _LIBCPP_OVERRIDABLE_FUNC_VIS _LIBCPP_FUNC_VIS
+#endif
+
+#ifndef _LIBCPP_EXCEPTION_ABI
+#  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+#    define _LIBCPP_EXCEPTION_ABI __attribute__ ((__visibility__("default")))
+#  else
+#    define _LIBCPP_EXCEPTION_ABI
+#  endif
+#endif
+
+#ifndef _LIBCPP_ENUM_VIS
+#  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS) && __has_attribute(__type_visibility__)
+#    define _LIBCPP_ENUM_VIS __attribute__ ((__type_visibility__("default")))
+#  else
+#    define _LIBCPP_ENUM_VIS
+#  endif
+#endif
+
+#ifndef _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
+#  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS) && __has_attribute(__type_visibility__)
+#    define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS __attribute__ ((__visibility__("default")))
+#  else
+#    define _LIBCPP_EXTERN_TEMPLATE_TYPE_VIS
+#  endif
+#endif
+
+#ifndef _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
+#define _LIBCPP_CLASS_TEMPLATE_INSTANTIATION_VIS
+#endif
+
+#if __has_attribute(internal_linkage)
+#  define _LIBCPP_INTERNAL_LINKAGE __attribute__ ((internal_linkage))
+#else
+#  define _LIBCPP_INTERNAL_LINKAGE _LIBCPP_ALWAYS_INLINE
+#endif
+
+#ifndef _LIBCPP_HIDE_FROM_ABI_PER_TU
+#  ifndef _LIBCPP_HIDE_FROM_ABI_PER_TU_BY_DEFAULT
+#    define _LIBCPP_HIDE_FROM_ABI_PER_TU 0
+#  else
+#    define _LIBCPP_HIDE_FROM_ABI_PER_TU 1
+#  endif
+#endif
+
+#ifndef _LIBCPP_HIDE_FROM_ABI
+#  if _LIBCPP_HIDE_FROM_ABI_PER_TU
+#    define _LIBCPP_HIDE_FROM_ABI _LIBCPP_HIDDEN _LIBCPP_INTERNAL_LINKAGE
+#  else
+#    define _LIBCPP_HIDE_FROM_ABI _LIBCPP_HIDDEN _LIBCPP_ALWAYS_INLINE
+#  endif
+#endif
+
+// Just so we can migrate to _LIBCPP_HIDE_FROM_ABI gradually.
+#define _LIBCPP_INLINE_VISIBILITY _LIBCPP_HIDE_FROM_ABI
+
+#ifndef _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY
+#  if !defined(_LIBCPP_DISABLE_VISIBILITY_ANNOTATIONS)
+#    define _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY __attribute__((__visibility__("default"), __always_inline__))
+#  else
+#    define _LIBCPP_EXTERN_TEMPLATE_INLINE_VISIBILITY __attribute__((__always_inline__))
+#  endif
+#endif
+
+#ifndef _LIBCPP_PREFERRED_OVERLOAD
+#  if __has_attribute(__enable_if__)
+#    define _LIBCPP_PREFERRED_OVERLOAD __attribute__ ((__enable_if__(true, "")))
+#  endif
+#endif
+
+#ifndef _LIBCPP_HAS_NO_NOEXCEPT
+#  define _NOEXCEPT noexcept
+#  define _NOEXCEPT_(x) noexcept(x)
+#else
+#  define _NOEXCEPT throw()
+#  define _NOEXCEPT_(x)
+#endif
+
+#if defined(_LIBCPP_DEBUG_USE_EXCEPTIONS)
+#  if !defined(_LIBCPP_DEBUG)
+#    error cannot use _LIBCPP_DEBUG_USE_EXCEPTIONS unless _LIBCPP_DEBUG is defined
+#  endif
+#  ifdef _LIBCPP_HAS_NO_NOEXCEPT
+#    define _NOEXCEPT_DEBUG
+#    define _NOEXCEPT_DEBUG_(x)
+#  else
+#    define _NOEXCEPT_DEBUG noexcept(false)
+#    define _NOEXCEPT_DEBUG_(x) noexcept(false)
+#  endif
+#else
+#  define _NOEXCEPT_DEBUG _NOEXCEPT
+#  define _NOEXCEPT_DEBUG_(x) _NOEXCEPT_(x)
+#endif
+
+#ifdef _LIBCPP_HAS_NO_UNICODE_CHARS
+typedef unsigned short char16_t;
+typedef unsigned int   char32_t;
+#endif  // _LIBCPP_HAS_NO_UNICODE_CHARS
+
+#ifndef __SIZEOF_INT128__
+#define _LIBCPP_HAS_NO_INT128
+#endif
+
+#ifdef _LIBCPP_CXX03_LANG
+#  if __has_extension(c_static_assert)
+#    define static_assert(__b, __m) _Static_assert(__b, __m)
+#  else
+extern "C++" {
+template <bool> struct __static_assert_test;
+template <> struct __static_assert_test<true> {};
+template <unsigned> struct __static_assert_check {};
+}
+#    define static_assert(__b, __m) \
+       typedef __static_assert_check<sizeof(__static_assert_test<(__b)>)> \
+       _LIBCPP_CONCAT(__t, __LINE__)
+#  endif // __has_extension(c_static_assert)
+#endif  // _LIBCPP_CXX03_LANG
+
+#ifdef _LIBCPP_HAS_NO_DECLTYPE
+// GCC 4.6 provides __decltype in all standard modes.
+#  if __has_keyword(__decltype) || _LIBCPP_CLANG_VER >= 304 || _GNUC_VER >= 406
+#    define decltype(__x) __decltype(__x)
+#  else
+#    define decltype(__x) __typeof__(__x)
+#  endif
+#endif
+
+#ifdef _LIBCPP_HAS_NO_CONSTEXPR
+#  define _LIBCPP_CONSTEXPR
+#else
+#  define _LIBCPP_CONSTEXPR constexpr
+#endif
+
+#ifdef _LIBCPP_CXX03_LANG
+#  define _LIBCPP_DEFAULT {}
+#else
+#  define _LIBCPP_DEFAULT = default;
+#endif
+
+#ifdef _LIBCPP_CXX03_LANG
+#  define _LIBCPP_EQUAL_DELETE
+#else
+#  define _LIBCPP_EQUAL_DELETE = delete
+#endif
+
+#ifdef __GNUC__
+#  define _NOALIAS __attribute__((__malloc__))
+#else
+#  define _NOALIAS
+#endif
+
+#if __has_feature(cxx_explicit_conversions) || defined(__IBMCPP__) || \
+    (!defined(_LIBCPP_CXX03_LANG) && defined(__GNUC__)) // All supported GCC versions
+#  define _LIBCPP_EXPLICIT explicit
+#else
+#  define _LIBCPP_EXPLICIT
+#endif
+
+#if !__has_builtin(__builtin_operator_new) || !__has_builtin(__builtin_operator_delete)
+#define _LIBCPP_HAS_NO_BUILTIN_OPERATOR_NEW_DELETE
+#endif
+
+#ifdef _LIBCPP_HAS_NO_STRONG_ENUMS
+#  define _LIBCPP_DECLARE_STRONG_ENUM(x) struct _LIBCPP_TYPE_VIS x { enum __lx
+#  define _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(x) \
+     __lx __v_; \
+     _LIBCPP_INLINE_VISIBILITY x(__lx __v) : __v_(__v) {} \
+     _LIBCPP_INLINE_VISIBILITY explicit x(int __v) : __v_(static_cast<__lx>(__v)) {} \
+     _LIBCPP_INLINE_VISIBILITY operator int() const {return __v_;} \
+     };
+#else  // _LIBCPP_HAS_NO_STRONG_ENUMS
+#  define _LIBCPP_DECLARE_STRONG_ENUM(x) enum class _LIBCPP_ENUM_VIS x
+#  define _LIBCPP_DECLARE_STRONG_ENUM_EPILOG(x)
+#endif  // _LIBCPP_HAS_NO_STRONG_ENUMS
+
+#ifdef _LIBCPP_DEBUG
+#  if _LIBCPP_DEBUG == 0
+#    define _LIBCPP_DEBUG_LEVEL 1
+#  elif _LIBCPP_DEBUG == 1
+#    define _LIBCPP_DEBUG_LEVEL 2
+#  else
+#    error Supported values for _LIBCPP_DEBUG are 0 and 1
+#  endif
+#  if !defined(_LIBCPP_BUILDING_LIBRARY)
+#    define _LIBCPP_EXTERN_TEMPLATE(...)
+#  endif
+#endif
+
+#ifdef _LIBCPP_DISABLE_EXTERN_TEMPLATE
+#define _LIBCPP_EXTERN_TEMPLATE(...)
+#define _LIBCPP_EXTERN_TEMPLATE2(...)
+#endif
+
+#ifndef _LIBCPP_EXTERN_TEMPLATE
+#define _LIBCPP_EXTERN_TEMPLATE(...) extern template __VA_ARGS__;
+#endif
+
+#ifndef _LIBCPP_EXTERN_TEMPLATE2
+#define _LIBCPP_EXTERN_TEMPLATE2(...) extern template __VA_ARGS__;
+#endif
+
+#if defined(__APPLE__) && defined(__LP64__) && !defined(__x86_64__)
+#define _LIBCPP_NONUNIQUE_RTTI_BIT (1ULL << 63)
+#endif
+
+#if defined(__APPLE__) || defined(__FreeBSD__) || defined(_LIBCPP_MSVCRT_LIKE) || \
+    defined(__sun__) || defined(__NetBSD__) || defined(__CloudABI__)
+#define _LIBCPP_LOCALE__L_EXTENSIONS 1
+#endif
+
+#if defined(__unix__) || (defined(__APPLE__) && defined(__MACH__))
+// Most unix variants have catopen.  These are the specific ones that don't.
+#  if !defined(__BIONIC__) && !defined(_NEWLIB_VERSION)
+#    define _LIBCPP_HAS_CATOPEN 1
+#  endif
+#endif
+
+#ifdef __FreeBSD__
+#define _DECLARE_C99_LDBL_MATH 1
+#endif
+
+// If we are getting operator new from the MSVC CRT, then allocation overloads
+// for align_val_t were added in 19.12, aka VS 2017 version 15.3.
+#if defined(_LIBCPP_MSVCRT) && defined(_MSC_VER) && _MSC_VER < 1912
+#define _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
+#endif
+
+#if defined(__APPLE__)
+#  if !defined(__MAC_OS_X_VERSION_MIN_REQUIRED) && \
+      defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__)
+#    define __MAC_OS_X_VERSION_MIN_REQUIRED __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__
+#  endif
+#  if defined(__MAC_OS_X_VERSION_MIN_REQUIRED)
+#    if __MAC_OS_X_VERSION_MIN_REQUIRED < 1060
+#      define _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
+#    endif
+#  endif
+#endif // defined(__APPLE__)
+
+#if !defined(_LIBCPP_HAS_NO_ALIGNED_ALLOCATION) && \
+    !defined(_LIBCPP_BUILDING_LIBRARY) && \
+    (!defined(__cpp_aligned_new) || __cpp_aligned_new < 201606)
+#  define _LIBCPP_HAS_NO_ALIGNED_ALLOCATION
+#endif
+
+#if defined(__APPLE__) || defined(__FreeBSD__)
+#define _LIBCPP_HAS_DEFAULTRUNELOCALE
+#endif
+
+#if defined(__APPLE__) || defined(__FreeBSD__) || defined(__sun__)
+#define _LIBCPP_WCTYPE_IS_MASK
+#endif
+
+#if _LIBCPP_STD_VER > 11
+#  define _LIBCPP_DEPRECATED [[deprecated]]
+#else
+#  define _LIBCPP_DEPRECATED
+#endif
+
+#if _LIBCPP_STD_VER <= 11
+#  define _LIBCPP_EXPLICIT_AFTER_CXX11
+#  define _LIBCPP_DEPRECATED_AFTER_CXX11
+#else
+#  define _LIBCPP_EXPLICIT_AFTER_CXX11 explicit
+#  define _LIBCPP_DEPRECATED_AFTER_CXX11 [[deprecated]]
+#endif
+
+#if _LIBCPP_STD_VER > 11 && !defined(_LIBCPP_HAS_NO_CXX14_CONSTEXPR)
+#  define _LIBCPP_CONSTEXPR_AFTER_CXX11 constexpr
+#else
+#  define _LIBCPP_CONSTEXPR_AFTER_CXX11
+#endif
+
+#if _LIBCPP_STD_VER > 14 && !defined(_LIBCPP_HAS_NO_CXX14_CONSTEXPR)
+#  define _LIBCPP_CONSTEXPR_AFTER_CXX14 constexpr
+#else
+#  define _LIBCPP_CONSTEXPR_AFTER_CXX14
+#endif
+
+#if _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_HAS_NO_CXX14_CONSTEXPR)
+#  define _LIBCPP_CONSTEXPR_AFTER_CXX17 constexpr
+#else
+#  define _LIBCPP_CONSTEXPR_AFTER_CXX17
+#endif
+
+#if __has_cpp_attribute(nodiscard) && _LIBCPP_STD_VER > 17 && !defined(_LIBCPP_DISABLE_NODISCARD_AFTER_CXX17)
+#  define _LIBCPP_NODISCARD_AFTER_CXX17 [[nodiscard]]
+#else
+#  define _LIBCPP_NODISCARD_AFTER_CXX17
+#endif
+
+#if _LIBCPP_STD_VER > 14 && defined(__cpp_inline_variables) && (__cpp_inline_variables >= 201606L)
+#  define _LIBCPP_INLINE_VAR inline
+#else
+#  define _LIBCPP_INLINE_VAR
+#endif
+
+#ifdef _LIBCPP_HAS_NO_RVALUE_REFERENCES
+#  define _LIBCPP_EXPLICIT_MOVE(x) _VSTD::move(x)
+#else
+#  define _LIBCPP_EXPLICIT_MOVE(x) (x)
+#endif
+
+#ifndef _LIBCPP_CONSTEXPR_IF_NODEBUG
+#if defined(_LIBCPP_DEBUG) || defined(_LIBCPP_HAS_NO_CXX14_CONSTEXPR)
+#define _LIBCPP_CONSTEXPR_IF_NODEBUG
+#else
+#define _LIBCPP_CONSTEXPR_IF_NODEBUG constexpr
+#endif
+#endif
+
+#ifndef _LIBCPP_HAS_NO_ASAN
+_LIBCPP_FUNC_VIS extern "C" void __sanitizer_annotate_contiguous_container(
+  const void *, const void *, const void *, const void *);
+#endif
+
+// Try to find out if RTTI is disabled.
+// g++ and cl.exe have RTTI on by default and define a macro when it is.
+// g++ only defines the macro in 4.3.2 and onwards.
+#if !defined(_LIBCPP_NO_RTTI)
+#  if defined(__GNUC__) && \
+      ((__GNUC__ >= 5) || \
+       (__GNUC__ == 4 && (__GNUC_MINOR__ >= 3 || __GNUC_PATCHLEVEL__ >= 2))) && \
+      !defined(__GXX_RTTI)
+#    define _LIBCPP_NO_RTTI
+#  elif defined(_LIBCPP_COMPILER_MSVC) && !defined(_CPPRTTI)
+#    define _LIBCPP_NO_RTTI
+#  endif
+#endif
+
+#ifndef _LIBCPP_WEAK
+#define _LIBCPP_WEAK __attribute__((__weak__))
+#endif
+
+// Thread API
+#if !defined(_LIBCPP_HAS_NO_THREADS) && \
+    !defined(_LIBCPP_HAS_THREAD_API_PTHREAD) && \
+    !defined(_LIBCPP_HAS_THREAD_API_WIN32) && \
+    !defined(_LIBCPP_HAS_THREAD_API_EXTERNAL)
+#  if defined(__FreeBSD__) || \
+      defined(__Fuchsia__) || \
+      defined(__NetBSD__) || \
+      defined(__linux__) || \
+      defined(__APPLE__) || \
+      defined(__CloudABI__) || \
+      defined(__sun__) || \
+      (defined(__MINGW32__) && __has_include(<pthread.h>))
+#    define _LIBCPP_HAS_THREAD_API_PTHREAD
+#  elif defined(_LIBCPP_WIN32API)
+#    define _LIBCPP_HAS_THREAD_API_WIN32
+#  else
+#    error "No thread API"
+#  endif // _LIBCPP_HAS_THREAD_API
+#endif // _LIBCPP_HAS_NO_THREADS
+
+#if defined(_LIBCPP_HAS_NO_THREADS) && defined(_LIBCPP_HAS_THREAD_API_PTHREAD)
+#error _LIBCPP_HAS_THREAD_API_PTHREAD may only be defined when \
+       _LIBCPP_HAS_NO_THREADS is not defined.
+#endif
+
+#if defined(_LIBCPP_HAS_NO_THREADS) && defined(_LIBCPP_HAS_THREAD_API_EXTERNAL)
+#error _LIBCPP_HAS_THREAD_API_EXTERNAL may not be defined when \
+       _LIBCPP_HAS_NO_THREADS is defined.
+#endif
+
+#if defined(_LIBCPP_HAS_NO_MONOTONIC_CLOCK) && !defined(_LIBCPP_HAS_NO_THREADS)
+#error _LIBCPP_HAS_NO_MONOTONIC_CLOCK may only be defined when \
+       _LIBCPP_HAS_NO_THREADS is defined.
+#endif
+
+// Systems that use capability-based security (FreeBSD with Capsicum,
+// Nuxi CloudABI) may only provide local filesystem access (using *at()).
+// Functions like open(), rename(), unlink() and stat() should not be
+// used, as they attempt to access the global filesystem namespace.
+#ifdef __CloudABI__
+#define _LIBCPP_HAS_NO_GLOBAL_FILESYSTEM_NAMESPACE
+#endif
+
+// CloudABI is intended for running networked services. Processes do not
+// have standard input and output channels.
+#ifdef __CloudABI__
+#define _LIBCPP_HAS_NO_STDIN
+#define _LIBCPP_HAS_NO_STDOUT
+#endif
+
+#if defined(__BIONIC__) || defined(__CloudABI__) ||                            \
+    defined(__Fuchsia__) || defined(_LIBCPP_HAS_MUSL_LIBC)
+#define _LIBCPP_PROVIDES_DEFAULT_RUNE_TABLE
+#endif
+
+// Thread-unsafe functions such as strtok() and localtime()
+// are not available.
+#ifdef __CloudABI__
+#define _LIBCPP_HAS_NO_THREAD_UNSAFE_C_FUNCTIONS
+#endif
+
+#if __has_feature(cxx_atomic) || __has_extension(c_atomic) || __has_keyword(_Atomic)
+#  define _LIBCPP_HAS_C_ATOMIC_IMP
+#elif _GNUC_VER > 407
+#  define _LIBCPP_HAS_GCC_ATOMIC_IMP
+#endif
+
+#if (!defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_GCC_ATOMIC_IMP)) \
+     || defined(_LIBCPP_HAS_NO_THREADS)
+#define _LIBCPP_HAS_NO_ATOMIC_HEADER
+#endif
+
+#ifndef _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
+#define _LIBCPP_DISABLE_UBSAN_UNSIGNED_INTEGER_CHECK
+#endif
+
+#if defined(_LIBCPP_ENABLE_THREAD_SAFETY_ANNOTATIONS)
+#  if defined(__clang__) && __has_attribute(acquire_capability)
+// Work around the attribute handling in clang.  When both __declspec and
+// __attribute__ are present, the processing goes awry preventing the definition
+// of the types.
+#    if !defined(_LIBCPP_OBJECT_FORMAT_COFF)
+#      define _LIBCPP_HAS_THREAD_SAFETY_ANNOTATIONS
+#    endif
+#  endif
+#endif
+
+#if __has_attribute(require_constant_initialization)
+#  define _LIBCPP_SAFE_STATIC __attribute__((__require_constant_initialization__))
+#else
+#  define _LIBCPP_SAFE_STATIC
+#endif
+
+#if !__has_builtin(__builtin_addressof) && _GNUC_VER < 700
+#define _LIBCPP_HAS_NO_BUILTIN_ADDRESSOF
+#endif
+
+#if !defined(_LIBCPP_HAS_NO_OFF_T_FUNCTIONS)
+#  if defined(_LIBCPP_MSVCRT) || defined(_NEWLIB_VERSION)
+#    define _LIBCPP_HAS_NO_OFF_T_FUNCTIONS
+#  endif
+#endif
+
+#if __has_attribute(diagnose_if) && !defined(_LIBCPP_DISABLE_ADDITIONAL_DIAGNOSTICS)
+#  define _LIBCPP_DIAGNOSE_WARNING(...) \
+     __attribute__((diagnose_if(__VA_ARGS__, "warning")))
+#  define _LIBCPP_DIAGNOSE_ERROR(...) \
+     __attribute__((diagnose_if(__VA_ARGS__, "error")))
+#else
+#  define _LIBCPP_DIAGNOSE_WARNING(...)
+#  define _LIBCPP_DIAGNOSE_ERROR(...)
+#endif
+
+#if __has_attribute(fallthough) || _GNUC_VER >= 700
+// Use a function like macro to imply that it must be followed by a semicolon
+#  define _LIBCPP_FALLTHROUGH() __attribute__((__fallthrough__))
+#else
+#  define _LIBCPP_FALLTHROUGH() ((void)0)
+#endif
+
+#if defined(_LIBCPP_ABI_MICROSOFT) && \
+    (defined(_LIBCPP_COMPILER_MSVC) || __has_declspec_attribute(empty_bases))
+#  define _LIBCPP_DECLSPEC_EMPTY_BASES __declspec(empty_bases)
+#else
+#  define _LIBCPP_DECLSPEC_EMPTY_BASES
+#endif
+
+#if defined(_LIBCPP_ENABLE_CXX17_REMOVED_FEATURES)
+#define _LIBCPP_ENABLE_CXX17_REMOVED_AUTO_PTR
+#define _LIBCPP_ENABLE_CXX17_REMOVED_UNEXPECTED_FUNCTIONS
+#define _LIBCPP_ENABLE_CXX17_REMOVED_RANDOM_SHUFFLE
+#define _LIBCPP_ENABLE_CXX17_REMOVED_BINDERS
+#endif // _LIBCPP_ENABLE_CXX17_REMOVED_FEATURES
+
+#if !defined(__cpp_deduction_guides) || __cpp_deduction_guides < 201611
+#define _LIBCPP_HAS_NO_DEDUCTION_GUIDES
+#endif
+
+#if !__has_keyword(__is_aggregate) && (_GNUC_VER_NEW < 7001)
+#define _LIBCPP_HAS_NO_IS_AGGREGATE
+#endif
+
+#if !defined(__cpp_coroutines) || __cpp_coroutines < 201703L
+#define _LIBCPP_HAS_NO_COROUTINES
+#endif
+
+// FIXME: Correct this macro when either (A) a feature test macro for the
+// spaceship operator is provided, or (B) a compiler provides a complete
+// implementation.
+#define _LIBCPP_HAS_NO_SPACESHIP_OPERATOR
+
+// Decide whether to use availability macros.
+#if !defined(_LIBCPP_BUILDING_LIBRARY) &&                                      \
+    !defined(_LIBCPP_DISABLE_AVAILABILITY) &&                                  \
+    __has_feature(attribute_availability_with_strict) &&                       \
+    __has_feature(attribute_availability_in_templates)
+#  ifdef __APPLE__
+#    define _LIBCPP_USE_AVAILABILITY_APPLE
+#  endif
+#endif
+
+// Define availability macros.
+#if defined(_LIBCPP_USE_AVAILABILITY_APPLE)
+#  define _LIBCPP_AVAILABILITY_SHARED_MUTEX                                    \
+     __attribute__((availability(macosx,strict,introduced=10.12)))             \
+     __attribute__((availability(ios,strict,introduced=10.0)))                 \
+     __attribute__((availability(tvos,strict,introduced=10.0)))                \
+     __attribute__((availability(watchos,strict,introduced=3.0)))
+#  define _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS __attribute__((unavailable))
+#  define _LIBCPP_AVAILABILITY_BAD_ARRAY_LENGTH __attribute__((unavailable))
+#  define _LIBCPP_AVAILABILITY_BAD_ANY_CAST __attribute__((unavailable))
+#  define _LIBCPP_AVAILABILITY_UNCAUGHT_EXCEPTIONS                             \
+     __attribute__((availability(macosx,strict,introduced=10.12)))             \
+     __attribute__((availability(ios,strict,introduced=10.0)))                 \
+     __attribute__((availability(tvos,strict,introduced=10.0)))                \
+     __attribute__((availability(watchos,strict,introduced=3.0)))
+#  define _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE                                \
+     __attribute__((availability(macosx,strict,introduced=10.12)))             \
+     __attribute__((availability(ios,strict,introduced=10.0)))                 \
+     __attribute__((availability(tvos,strict,introduced=10.0)))                \
+     __attribute__((availability(watchos,strict,introduced=3.0)))
+#  define _LIBCPP_AVAILABILITY_FUTURE_ERROR                                    \
+     __attribute__((availability(ios,strict,introduced=6.0)))
+#  define _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE                                 \
+     __attribute__((availability(macosx,strict,introduced=10.9)))              \
+     __attribute__((availability(ios,strict,introduced=7.0)))
+#  define _LIBCPP_AVAILABILITY_LOCALE_CATEGORY                                 \
+     __attribute__((availability(macosx,strict,introduced=10.9)))              \
+     __attribute__((availability(ios,strict,introduced=7.0)))
+#  define _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR                               \
+     __attribute__((availability(macosx,strict,introduced=10.9)))              \
+     __attribute__((availability(ios,strict,introduced=7.0)))
+#else
+#  define _LIBCPP_AVAILABILITY_SHARED_MUTEX
+#  define _LIBCPP_AVAILABILITY_BAD_OPTIONAL_ACCESS
+#  define _LIBCPP_AVAILABILITY_BAD_ARRAY_LENGTH
+#  define _LIBCPP_AVAILABILITY_BAD_ANY_CAST
+#  define _LIBCPP_AVAILABILITY_UNCAUGHT_EXCEPTIONS
+#  define _LIBCPP_AVAILABILITY_SIZED_NEW_DELETE
+#  define _LIBCPP_AVAILABILITY_FUTURE_ERROR
+#  define _LIBCPP_AVAILABILITY_TYPEINFO_VTABLE
+#  define _LIBCPP_AVAILABILITY_LOCALE_CATEGORY
+#  define _LIBCPP_AVAILABILITY_ATOMIC_SHARED_PTR
+#endif
+
+// Define availability that depends on _LIBCPP_NO_EXCEPTIONS.
+#ifdef _LIBCPP_NO_EXCEPTIONS
+#  define _LIBCPP_AVAILABILITY_DYNARRAY
+#  define _LIBCPP_AVAILABILITY_FUTURE
+#  define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST
+#else
+#  define _LIBCPP_AVAILABILITY_DYNARRAY _LIBCPP_AVAILABILITY_BAD_ARRAY_LENGTH
+#  define _LIBCPP_AVAILABILITY_FUTURE _LIBCPP_AVAILABILITY_FUTURE_ERROR
+#  define _LIBCPP_AVAILABILITY_THROW_BAD_ANY_CAST                              \
+     _LIBCPP_AVAILABILITY_BAD_ANY_CAST
+#endif
+
+// Availability of stream API in the dylib got dropped and re-added.  The
+// extern template should effectively be available at:
+//    availability(macosx,introduced=10.9)
+//    availability(ios,introduced=7.0)
+#if defined(_LIBCPP_USE_AVAILABILITY_APPLE) &&                                 \
+    ((defined(__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__) &&                \
+      __ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__ < 1090) ||                 \
+     (defined(__ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__) &&               \
+      __ENVIRONMENT_IPHONE_OS_VERSION_MIN_REQUIRED__ < 70000))
+#define _LIBCPP_AVAILABILITY_NO_STREAMS_EXTERN_TEMPLATE
+#endif
+
+#if defined(_LIBCPP_COMPILER_IBM)
+#define _LIBCPP_HAS_NO_PRAGMA_PUSH_POP_MACRO
+#endif
+
+#if defined(_LIBCPP_HAS_NO_PRAGMA_PUSH_POP_MACRO)
+#  define _LIBCPP_PUSH_MACROS
+#  define _LIBCPP_POP_MACROS
+#else
+  // Don't warn about macro conflicts when we can restore them at the
+  // end of the header.
+#  ifndef _LIBCPP_DISABLE_MACRO_CONFLICT_WARNINGS
+#    define _LIBCPP_DISABLE_MACRO_CONFLICT_WARNINGS
+#  endif
+#  if defined(_LIBCPP_COMPILER_MSVC)
+#    define _LIBCPP_PUSH_MACROS    \
+       __pragma(push_macro("min")) \
+       __pragma(push_macro("max"))
+#    define _LIBCPP_POP_MACROS     \
+       __pragma(pop_macro("min"))  \
+       __pragma(pop_macro("max"))
+#  else
+#    define _LIBCPP_PUSH_MACROS        \
+       _Pragma("push_macro(\"min\")")  \
+       _Pragma("push_macro(\"max\")")
+#    define _LIBCPP_POP_MACROS         \
+       _Pragma("pop_macro(\"min\")")   \
+       _Pragma("pop_macro(\"max\")")
+#  endif
+#endif // defined(_LIBCPP_HAS_NO_PRAGMA_PUSH_POP_MACRO)
+
+#ifndef _LIBCPP_NO_AUTO_LINK
+#  if defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_BUILDING_LIBRARY)
+#    if defined(_DLL)
+#      pragma comment(lib, "c++.lib")
+#    else
+#      pragma comment(lib, "libc++.lib")
+#    endif
+#  endif // defined(_LIBCPP_ABI_MICROSOFT) && !defined(_LIBCPP_BUILDING_LIBRARY)
+#endif // _LIBCPP_NO_AUTO_LINK
+
+#endif // __cplusplus
+
+#endif // _LIBCPP_CONFIG