From 7671e53b668093edbf3f20fc5e43a341626c743a Mon Sep 17 00:00:00 2001
From: Douglas Gregor <dgregor@apple.com>
Date: Fri, 16 Dec 2011 16:34:57 +0000
Subject: [PATCH] If there is a definition of an ObjCInterfaceDecl, make it the
 Decl returned from the corresponding ObjCInterfaceType

llvm-svn: 146740
---
 clang/include/clang/AST/Type.h | 3 ++-
 clang/lib/AST/ASTContext.cpp   | 4 ++++
 clang/lib/AST/DeclObjC.cpp     | 6 +++++-
 3 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/clang/include/clang/AST/Type.h b/clang/include/clang/AST/Type.h
index c9bee81..de58396 100644
--- a/clang/include/clang/AST/Type.h
+++ b/clang/include/clang/AST/Type.h
@@ -4139,12 +4139,13 @@ inline ObjCProtocolDecl **ObjCObjectType::getProtocolStorage() {
 ///   - It is its own base type.  That is, if T is an ObjCInterfaceType*,
 ///     T->getBaseType() == QualType(T, 0).
 class ObjCInterfaceType : public ObjCObjectType {
-  ObjCInterfaceDecl *Decl;
+  mutable ObjCInterfaceDecl *Decl;
 
   ObjCInterfaceType(const ObjCInterfaceDecl *D)
     : ObjCObjectType(Nonce_ObjCInterface),
       Decl(const_cast<ObjCInterfaceDecl*>(D)) {}
   friend class ASTContext;  // ASTContext creates these.
+  friend class ObjCInterfaceDecl;
 
 public:
   /// getDecl - Get the declaration of this interface.
diff --git a/clang/lib/AST/ASTContext.cpp b/clang/lib/AST/ASTContext.cpp
index de0250c..9784191 100644
--- a/clang/lib/AST/ASTContext.cpp
+++ b/clang/lib/AST/ASTContext.cpp
@@ -2819,6 +2819,10 @@ QualType ASTContext::getObjCInterfaceType(const ObjCInterfaceDecl *Decl,
     return QualType(PrevDecl->TypeForDecl, 0);
   }
 
+  // Prefer the definition, if there is one.
+  if (const ObjCInterfaceDecl *Def = Decl->getDefinition())
+    Decl = Def;
+  
   void *Mem = Allocate(sizeof(ObjCInterfaceType), TypeAlignment);
   ObjCInterfaceType *T = new (Mem) ObjCInterfaceType(Decl);
   Decl->TypeForDecl = T;
diff --git a/clang/lib/AST/DeclObjC.cpp b/clang/lib/AST/DeclObjC.cpp
index 317dc95..02cc988 100644
--- a/clang/lib/AST/DeclObjC.cpp
+++ b/clang/lib/AST/DeclObjC.cpp
@@ -225,7 +225,11 @@ void ObjCInterfaceDecl::mergeClassExtensionProtocolList(
 void ObjCInterfaceDecl::allocateDefinitionData() {
   assert(!hasDefinition() && "ObjC class already has a definition");
   Data = new (getASTContext()) DefinitionData();
-  Data->Definition = this;  
+  Data->Definition = this;
+
+  // Make the type point at the definition, now that we have one.
+  if (TypeForDecl)
+    cast<ObjCInterfaceType>(TypeForDecl)->Decl = this;
 }
 
 void ObjCInterfaceDecl::startDefinition() {
-- 
2.7.4