From 6dd3f39daeff5c14bf8cacad786d74463b800948 Mon Sep 17 00:00:00 2001
From: Fariborz Jahanian <fjahanian@apple.com>
Date: Tue, 6 Sep 2011 23:32:40 +0000
Subject: [PATCH] objc-gc: Adds support for  "weak" property attribute under
 GC. // rdar://10073896

llvm-svn: 139203
---
 clang/lib/Sema/SemaObjCProperty.cpp        |  6 +++++
 clang/test/CodeGenObjC/gc-weak-attribute.m | 28 ++++++++++++++++++++++
 2 files changed, 34 insertions(+)
 create mode 100644 clang/test/CodeGenObjC/gc-weak-attribute.m

diff --git a/clang/lib/Sema/SemaObjCProperty.cpp b/clang/lib/Sema/SemaObjCProperty.cpp
index 84052fd9d835..bf4939d9fd66 100644
--- a/clang/lib/Sema/SemaObjCProperty.cpp
+++ b/clang/lib/Sema/SemaObjCProperty.cpp
@@ -594,6 +594,12 @@ Decl *Sema::ActOnPropertyImplDecl(Scope *S,
     ObjCPropertyDecl::PropertyAttributeKind kind 
       = property->getPropertyAttributes();
     QualType PropType = Context.getCanonicalType(property->getType());
+    bool PropertyIsGCWeak = (kind & ObjCPropertyDecl::OBJC_PR_weak &&
+                             !getLangOptions().ObjCAutoRefCount &&
+                             getLangOptions().getGCMode() != 
+                             LangOptions::NonGC);
+    if (PropertyIsGCWeak)
+      PropType = Context.getObjCGCQualType(PropType, Qualifiers::Weak);
     QualType PropertyIvarType = PropType;
     if (PropType->isReferenceType())
       PropertyIvarType = cast<ReferenceType>(PropType)->getPointeeType();
diff --git a/clang/test/CodeGenObjC/gc-weak-attribute.m b/clang/test/CodeGenObjC/gc-weak-attribute.m
new file mode 100644
index 000000000000..44a91776637b
--- /dev/null
+++ b/clang/test/CodeGenObjC/gc-weak-attribute.m
@@ -0,0 +1,28 @@
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10 -fobjc-gc -fobjc-nonfragile-abi -emit-llvm -o - %s | FileCheck %s
+// rdar://10073896
+
+@interface I
+{
+  __weak id wObject;
+}
+@property (readwrite, weak) id representedObject;
+@property (readwrite, weak) id wObject;
+@property (readwrite, weak) __weak id wRandom;
+@property (readwrite, assign) __weak id wAnother;
+@end
+
+@implementation I
+@synthesize representedObject;
+@synthesize wObject;
+@synthesize wRandom;
+@synthesize wAnother;
+@end
+// CHECK:  call i8* @objc_read_weak
+// CHECK:  call i8* @objc_assign_weak
+// CHECK:  call i8* @objc_read_weak
+// CHECK:  call i8* @objc_assign_weak
+// CHECK:  call i8* @objc_read_weak
+// CHECK:  call i8* @objc_assign_weak
+// CHECK:  call i8* @objc_read_weak
+// CHECK:  call i8* @objc_assign_weak
+