|  | // RUN: %clang_cc1 -triple x86_64-apple-darwin10 -emit-llvm -o - %s | FileCheck -check-prefix=CHECK-X86-64 %s | 
|  |  | 
|  | __attribute__((weak_import)) @interface WeakRootClass @end | 
|  |  | 
|  | __attribute__((weak_import)) @interface WeakClass : WeakRootClass | 
|  | @end | 
|  |  | 
|  | @interface MySubclass : WeakClass @end | 
|  |  | 
|  | @implementation MySubclass @end | 
|  |  | 
|  | @implementation WeakClass(MyCategory) @end | 
|  |  | 
|  |  | 
|  | __attribute__((weak_import)) | 
|  | @interface WeakClass1 @end | 
|  |  | 
|  | @implementation WeakClass1(MyCategory) @end | 
|  |  | 
|  | @implementation WeakClass1(YourCategory) @end | 
|  |  | 
|  | __attribute__((weak_import)) | 
|  | @interface WeakClass3 | 
|  | + message; | 
|  | @end | 
|  |  | 
|  | int main() { | 
|  | [WeakClass3 message]; | 
|  | } | 
|  |  | 
|  | // CHECK-X86-64: OBJC_METACLASS_$_WeakRootClass" = extern_weak global | 
|  | // CHECK-X86-64: OBJC_METACLASS_$_WeakClass" = extern_weak global | 
|  | // CHECK-X86-64: OBJC_CLASS_$_WeakClass" = extern_weak global | 
|  | // CHECK-X86-64: OBJC_CLASS_$_WeakClass1" = extern_weak global | 
|  | // CHECK-X86-64: OBJC_CLASS_$_WeakClass3" = extern_weak global | 
|  |  | 
|  | // Root is being implemented here. No extern_weak. | 
|  | __attribute__((weak_import)) @interface Root @end | 
|  |  | 
|  | @interface Super : Root @end | 
|  |  | 
|  | @interface Sub : Super @end | 
|  |  | 
|  | @implementation Sub @end | 
|  |  | 
|  | @implementation Root @end | 
|  |  | 
|  | // CHECK-X86-64-NOT: OBJC_METACLASS_$_Root" = extern_weak global |