Remove Expr sugar decorating the CXXUuidofExpr node.

Summary: Sugar, like ConstantExpr, causes an infinite expansion of the template object.

Reviewers: rsmith, aaron.ballman

Reviewed By: aaron.ballman

Subscribers: riccibruno, aaron.ballman, cfe-commits, tzik, rnk

Differential Revision: https://reviews.llvm.org/D57114

llvm-svn: 352307
diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 54a01b7..2e73096 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -6308,7 +6308,7 @@
       // -- a predefined __func__ variable
       if (auto *E = Value.getLValueBase().dyn_cast<const Expr*>()) {
         if (isa<CXXUuidofExpr>(E)) {
-          Converted = TemplateArgument(ArgResult.get());
+          Converted = TemplateArgument(ArgResult.get()->IgnoreImpCasts());
           break;
         }
         Diag(Arg->getBeginLoc(), diag::err_template_arg_not_decl_ref)