Index: lib/Sema/Sema.cpp
===================================================================
--- lib/Sema/Sema.cpp
+++ lib/Sema/Sema.cpp
@@ -369,6 +369,13 @@
     }
   }
 
+  // If we are casting pointers, we need to make sure we deal with address
+  // spaces properly.
+  if (Kind == CK_NoOp && ExprTy->isPointerType() && TypeTy->isPointerType() &&
+      ExprTy->getPointeeType().getAddressSpace() !=
+          TypeTy->getPointeeType().getAddressSpace())
+    Kind = CK_AddressSpaceConversion;
+
   return ImplicitCastExpr::Create(Context, Ty, Kind, E, BasePath, VK);
 }