Fix PR14321, a crash when Clang is built with GCC 4.7 at -O1 or greater.

GCC 4.7 reuses stack slots fairly aggressively, which exposes more temporary
lifetime bugs.

No new test, this was caught by the existing CodeGenCXX/mangle-ms-templates.cpp.

llvm-svn: 168124

clang/lib/AST/MicrosoftMangle.cpp

@@ -373,7 +373,7 @@ isTemplate(const NamedDecl *ND,
       dyn_cast<ClassTemplateSpecializationDecl>(ND)) {
     TypeSourceInfo *TSI = Spec->getTypeAsWritten();
     if (TSI) {
-      TemplateSpecializationTypeLoc &TSTL =
+      TemplateSpecializationTypeLoc TSTL =
         cast<TemplateSpecializationTypeLoc>(TSI->getTypeLoc());
       TemplateArgumentListInfo LI(TSTL.getLAngleLoc(), TSTL.getRAngleLoc());
       for (unsigned i = 0, e = TSTL.getNumArgs(); i != e; ++i)