diff --git a/clang/lib/CodeGen/CGDebugInfo.cpp b/clang/lib/CodeGen/CGDebugInfo.cpp
index 0b2bb61..5770764 100644
--- a/clang/lib/CodeGen/CGDebugInfo.cpp
+++ b/clang/lib/CodeGen/CGDebugInfo.cpp
@@ -290,6 +290,8 @@
   const char *BTName = NULL;
   switch (BT->getKind()) {
   default:
+    assert(0 && "Unexpected builtin");
+    return llvm::DIType();
   case BuiltinType::Void:
     return llvm::DIType();
   case BuiltinType::ObjCClass: