diff --git a/clang/lib/AST/DeclPrinter.cpp b/clang/lib/AST/DeclPrinter.cpp
--- a/clang/lib/AST/DeclPrinter.cpp
+++ b/clang/lib/AST/DeclPrinter.cpp
@@ -588,7 +588,7 @@
   }
   EOut << " ";
   EOut.flush();
-  Out << EOut.str();
+  Out << Proto;
 }
 
 void DeclPrinter::VisitFunctionDecl(FunctionDecl *D) {