diff --git a/lib/CodeGen/CGObjCRuntime.h b/lib/CodeGen/CGObjCRuntime.h
index e478394..64e6808 100644
--- a/lib/CodeGen/CGObjCRuntime.h
+++ b/lib/CodeGen/CGObjCRuntime.h
@@ -167,6 +167,9 @@
   /// Return the runtime function for setting properties.
   virtual llvm::Constant *GetPropertySetFunction() = 0;
 
+  // API for atomic copying of qualified aggregates in setter/getter.
+  virtual llvm::Constant *GetCopyStructFunction() = 0;
+  
   /// GetClass - Return a reference to the class for the given
   /// interface decl.
   virtual llvm::Value *GetClass(CGBuilderTy &Builder,