Set a bit in IMAGE_INFO to indicate that we don't contain any

@synthesized ivars for superclasses.
 - <rdar://problem/6806371> [clang] Mark code without miscompiled
   @synthesized properties

llvm-svn: 69581

clang/lib/CodeGen/CGObjCMac.cpp

@@ -2426,9 +2426,15 @@ llvm::Value *CGObjCMac::EmitIvarOffset(CodeGen::CodeGenFunction &CGF,
 ///   unsigned flags;
 /// };
 enum ImageInfoFlags {
-  eImageInfo_FixAndContinue   = (1 << 0), // FIXME: Not sure what this implies
-  eImageInfo_GarbageCollected = (1 << 1), 
-  eImageInfo_GCOnly           = (1 << 2)  
+  eImageInfo_FixAndContinue      = (1 << 0), // FIXME: Not sure what
+                                             // this implies.
+  eImageInfo_GarbageCollected    = (1 << 1), 
+  eImageInfo_GCOnly              = (1 << 2),  
+  eImageInfo_OptimizedByDyld     = (1 << 3), // FIXME: When is this set.
+
+  // A flag indicating that the module has no instances of an
+  // @synthesize of a superclass variable. <rdar://problem/6803242>
+  eImageInfo_CorrectedSynthesize = (1 << 4)
 };
 
 void CGObjCMac::EmitImageInfo() {
@@ -2440,6 +2446,9 @@ void CGObjCMac::EmitImageInfo() {
     flags |= eImageInfo_GarbageCollected;
   if (CGM.getLangOptions().getGCMode() == LangOptions::GCOnly)
     flags |= eImageInfo_GCOnly;
+  
+  // We never allow @synthesize of a superclass property.
+  flags |= eImageInfo_CorrectedSynthesize;
 
   // Emitted as int[2];
   llvm::Constant *values[2] = {

clang/test/CodeGenObjC/image-info.m

@@ -0,0 +1,2 @@
+// RUN: clang-cc -triple x86_64-apple-darwin-10 -emit-llvm -o %t %s &&
+// RUN: grep -F '@"\01L_OBJC_IMAGE_INFO" = internal constant [2 x i32] [i32 0, i32 16], section "__OBJC, __image_info,regular"' %t