2 files changed, 17 insertions, 2 deletions
diff --git a/lib/AST/DeclBase.cpp b/lib/AST/DeclBase.cpp
index b7941506b0..024f370c56 100644
--- a/lib/AST/DeclBase.cpp
+++ b/lib/AST/DeclBase.cpp
@@ -779,9 +779,16 @@ DeclContext *DeclContext::getPrimaryContext() {
     return this;
 
   case Decl::ObjCInterface:
+    if (ObjCInterfaceDecl *Def = cast<ObjCInterfaceDecl>(this)->getDefinition())
+      return Def;
+      
+    return this;
+      
   case Decl::ObjCProtocol:
+    // FIXME: Update when protocols properly model forward declarations.
+    // For now, it's fine to fall through
+      
   case Decl::ObjCCategory:
-    // FIXME: Can Objective-C interfaces be forward-declared?
     return this;
 
   case Decl::ObjCImplementation:
diff --git a/lib/AST/DeclObjC.cpp b/lib/AST/DeclObjC.cpp
index decbd54c6d..1da0fab0ba 100644
--- a/lib/AST/DeclObjC.cpp
+++ b/lib/AST/DeclObjC.cpp
@@ -224,7 +224,15 @@ void ObjCInterfaceDecl::mergeClassExtensionProtocolList(
 
 void ObjCInterfaceDecl::allocateDefinitionData() {
   assert(!hasDefinition() && "ObjC class already has a definition");
-  Definition = new (getASTContext()) DefinitionData();  
+  Definition.setPointer(new (getASTContext()) DefinitionData());
+  Definition.setInt(true);
+  
+  // Update all of the declarations with a pointer to the definition.
+  for (redecl_iterator RD = redecls_begin(), RDEnd = redecls_end();
+       RD != RDEnd; ++RD) {
+    if (*RD != this)
+      RD->Definition.setPointer(Definition.getPointer());
+  }
 }
 
 void ObjCInterfaceDecl::startDefinition() {