Constant expression evaluation: support for default arguments.

llvm-svn: 144156
diff --git a/clang/lib/AST/ExprConstant.cpp b/clang/lib/AST/ExprConstant.cpp
index d6e263b..aa94990 100644
--- a/clang/lib/AST/ExprConstant.cpp
+++ b/clang/lib/AST/ExprConstant.cpp
@@ -935,6 +935,8 @@
     { return StmtVisitorTy::Visit(E->getResultExpr()); }
   RetTy VisitSubstNonTypeTemplateParmExpr(const SubstNonTypeTemplateParmExpr *E)
     { return StmtVisitorTy::Visit(E->getReplacement()); }
+  RetTy VisitCXXDefaultArgExpr(const CXXDefaultArgExpr *E)
+    { return StmtVisitorTy::Visit(E->getExpr()); }
 
   RetTy VisitBinaryConditionalOperator(const BinaryConditionalOperator *E) {
     OpaqueValueEvaluation opaque(Info, E->getOpaqueValue(), E->getCommon());