From 95d181936a19882ee1ca82b65cc40ef8ebf45905 Mon Sep 17 00:00:00 2001
From: Ted Kremenek <kremenek@apple.com>
Date: Tue, 12 May 2009 04:53:03 +0000
Subject: [PATCH] Fix <rdar://problem/6877235> Classes typedef-ed to CF objects
 should get the same treatment as CF objects

This was accomplished by having	'isTypeRef' recursively walk the typedef stack.

llvm-svn: 71538
---
 clang/lib/Analysis/CFRefCount.cpp    | 14 +++++++++++---
 clang/test/Analysis/retain-release.m | 21 +++++++++++++++++++++
 2 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/clang/lib/Analysis/CFRefCount.cpp b/clang/lib/Analysis/CFRefCount.cpp
index bc140077dc76..5120d4f0fc50 100644
--- a/clang/lib/Analysis/CFRefCount.cpp
+++ b/clang/lib/Analysis/CFRefCount.cpp
@@ -225,9 +225,17 @@ static bool hasSuffix(const char* s, const char* suffix) {
 static bool isRefType(QualType RetTy, const char* prefix,
                       ASTContext* Ctx = 0, const char* name = 0) {
   
-  if (TypedefType* TD = dyn_cast<TypedefType>(RetTy.getTypePtr())) {
-    const char* TDName = TD->getDecl()->getIdentifier()->getName();
-    return hasPrefix(TDName, prefix) && hasSuffix(TDName, "Ref");
+  // Recursively walk the typedef stack, allowing typedefs of reference types.
+  while (1) {
+    if (TypedefType* TD = dyn_cast<TypedefType>(RetTy.getTypePtr())) {
+      const char* TDName = TD->getDecl()->getIdentifier()->getName();
+      if (hasPrefix(TDName, prefix) && hasSuffix(TDName, "Ref"))
+        return true;
+      
+      RetTy = TD->getDecl()->getUnderlyingType();
+      continue;
+    }
+    break;
   }
 
   if (!Ctx || !name)
diff --git a/clang/test/Analysis/retain-release.m b/clang/test/Analysis/retain-release.m
index f4c2d2505414..5f2a1c8f8581 100644
--- a/clang/test/Analysis/retain-release.m
+++ b/clang/test/Analysis/retain-release.m
@@ -528,6 +528,27 @@ void rdar_6866843() {
  [pool drain];
 }
 
+
+//===----------------------------------------------------------------------===//
+// <rdar://problem/6877235> Classes typedef-ed to CF objects should get the same treatment as CF objects
+//===----------------------------------------------------------------------===//
+
+typedef CFTypeRef OtherRef;
+
+@interface RDar6877235 : NSObject {}
+- (CFTypeRef)_copyCFTypeRef;
+- (OtherRef)_copyOtherRef;
+@end
+
+@implementation RDar6877235
+- (CFTypeRef)_copyCFTypeRef {
+  return [[NSString alloc] init]; // no-warning
+}
+- (OtherRef)_copyOtherRef {
+  return [[NSString alloc] init]; // no-warning
+}
+@end
+
 //===----------------------------------------------------------------------===//
 // Tests of ownership attributes.
 //===----------------------------------------------------------------------===//