Teach libclang not to recursive into default argument expressions

llvm-svn: 112866
diff --git a/clang/tools/libclang/CIndex.cpp b/clang/tools/libclang/CIndex.cpp
index 2b3364c..89816ac 100644
--- a/clang/tools/libclang/CIndex.cpp
+++ b/clang/tools/libclang/CIndex.cpp
@@ -385,6 +385,7 @@
   // FIXME: InitListExpr (for the designators)
   // FIXME: DesignatedInitExpr
   bool VisitCXXTypeidExpr(CXXTypeidExpr *E);
+  bool VisitCXXDefaultArgExpr(CXXDefaultArgExpr *E) { return false; }
 };
 
 } // end anonymous namespace