From 33fa96244135d64e13d964401f3089c251a4aa0b Mon Sep 17 00:00:00 2001
From: Fariborz Jahanian <fjahanian@apple.com>
Date: Tue, 28 Jan 2014 20:41:15 +0000
Subject: [PATCH] Objective-C. provide legacy encoding of *id and *Class types
 instead of crashing.  // rdar://15824769.

llvm-svn: 200338
---
 clang/lib/AST/ASTContext.cpp         | 14 +++++++++++++-
 clang/test/CodeGenObjC/encode-test.m |  8 ++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index ad3bf5105dd2..9ee624c98b30 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -5440,7 +5440,19 @@ void ASTContext::getObjCEncodingForTypeImpl(QualType T, std::string& S,
     return;
   }
 
-  case Type::ObjCObject:
+  case Type::ObjCObject: {
+    // hack to match legacy encoding of *id and *Class
+    QualType Ty = getObjCObjectPointerType(CT);
+    if (Ty->isObjCIdType()) {
+      S += "{objc_object=}";
+      return;
+    }
+    else if (Ty->isObjCClassType()) {
+      S += "{objc_class=}";
+      return;
+    }
+  }
+  
   case Type::ObjCInterface: {
     // Ignore protocol qualifiers when mangling at this level.
     T = T->castAs<ObjCObjectType>()->getBaseType();
diff --git a/clang/test/CodeGenObjC/encode-test.m b/clang/test/CodeGenObjC/encode-test.m
index d6e7b6dfccad..a310a621ecf4 100644
--- a/clang/test/CodeGenObjC/encode-test.m
+++ b/clang/test/CodeGenObjC/encode-test.m
@@ -169,3 +169,11 @@ const char g11[] = @encode(void);
 // PR14628
 // CHECK: @g12 = constant [3 x i8] c"Ai\00"
 const char g12[] = @encode(_Atomic(int));
+
+// rdar://15824769
+id test_id = 0;
+Class test_class = 0;
+const char g13[] = @encode(__typeof__(*test_class));
+const char g14[] = @encode(__typeof__(*test_id));
+// CHECK: constant [14 x i8] c"{objc_class=}\00"
+// CHECK: constant [15 x i8] c"{objc_object=}\00"