Disable type merging with gc attributes.  This has a number of nasty 
properties at the moment:

1. It allows stuff like "__strong id x; __weak id x;".

2. For constructs like "__strong id x; id x;", subsequent references to 
x lose the objc_gc attribute.

3. This incorrectly allows merges involving the address_space attribute.

4. Constructs like "id x; /* some code using x */ __weak id x;" don't 
apply the objc_gc attribute consistently to all uses of x.

The first three can probably be fixed relatively easily; the fourth 
would be extremely difficult to fix.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@72683 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/AST/ASTContext.cpp b/lib/AST/ASTContext.cpp
index c719b0b..a4b9acc 100644
--- a/lib/AST/ASTContext.cpp
+++ b/lib/AST/ASTContext.cpp
@@ -3020,8 +3020,8 @@
   if (LHSCan.getCVRQualifiers() != RHSCan.getCVRQualifiers())
     return QualType();
 
-  Type::TypeClass LHSClass = LHSCan.getUnqualifiedType()->getTypeClass();
-  Type::TypeClass RHSClass = RHSCan.getUnqualifiedType()->getTypeClass();
+  Type::TypeClass LHSClass = LHSCan->getTypeClass();
+  Type::TypeClass RHSClass = RHSCan->getTypeClass();
 
   // We want to consider the two function types to be the same for these
   // comparisons, just force one to the other.
diff --git a/test/SemaObjC/objc2-merge-gc-attribue-decl.m b/test/SemaObjC/objc2-merge-gc-attribue-decl.m
index cdcd058..452d0cf 100644
--- a/test/SemaObjC/objc2-merge-gc-attribue-decl.m
+++ b/test/SemaObjC/objc2-merge-gc-attribue-decl.m
@@ -1,5 +1,7 @@
 // RUN: clang-cc -triple i386-apple-darwin9 -fobjc-gc -fsyntax-only -verify %s
-
+// This is really dangerous!  Disabling for now until we work out what's
+// supposed to happen here.
+// XFAIL
 @interface INTF @end
 
 extern INTF* p2;