[PATCH] Fix "#pragma clang __debug overflow_stack" for MSVC builds

[Rafael Ávila de Espíndola]

There is a FIXME in test/Makefile about moving the ULIMIT setting from the Makefile to lit. The Make bug you found is another reason to do it, but that can be in another patch.

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Comment at: lib/Lex/Pragma.cpp:929
@@ -928,2 +928,3 @@
   static void DebugOverflowStack() {
+    void* StackUser = &StackUser;
     void (*volatile Self)() = DebugOverflowStack;
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http://reviews.llvm.org/D5109