use CodeGenModule::EmitNullConstant in a couple of places.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@77915 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CodeGenModule.cpp b/lib/CodeGen/CodeGenModule.cpp
index ec9a97a..c37fbe2 100644
--- a/lib/CodeGen/CodeGenModule.cpp
+++ b/lib/CodeGen/CodeGenModule.cpp
@@ -810,6 +810,7 @@
     // exists. A use may still exists, however, so we still may need
     // to do a RAUW.
     assert(!ASTTy->isIncompleteType() && "Unexpected incomplete type");
+    Init = EmitNullConstant(D->getType());
     Init = llvm::Constant::getNullValue(getTypes().ConvertTypeForMem(ASTTy));
   } else {
     Init = EmitConstantExpr(D->getInit(), D->getType());