Fixed build on Mac, where g++ is a bit too dumb to see that a variable is always initialized.

Review URL: http://codereview.chromium.org/6893105

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@7709 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/ia32/code-stubs-ia32.cc

@@ -533,7 +533,7 @@ const char* TypeRecordingUnaryOpStub::GetName() {
       kMaxNameLength);
   if (name_ == NULL) return "OOM";
   const char* op_name = Token::Name(op_);
-  const char* overwrite_name;
+  const char* overwrite_name = NULL;  // Make g++ on Mac happy.
   switch (mode_) {
     case UNARY_NO_OVERWRITE: overwrite_name = "Alloc"; break;
     case UNARY_OVERWRITE: overwrite_name = "Overwrite"; break;