1 files changed, 4 insertions, 1 deletions
diff --git a/include/clang/AST/DeclBase.h b/include/clang/AST/DeclBase.h
index 6382bf3694..6aef681d75 100644
--- a/include/clang/AST/DeclBase.h
+++ b/include/clang/AST/DeclBase.h
@@ -15,6 +15,7 @@
 #define LLVM_CLANG_AST_DECLBASE_H
 
 #include "clang/AST/Attr.h"
+#include "clang/AST/DeclarationName.h"
 #include "clang/AST/Type.h"
 #include "clang/Basic/Specifiers.h"
 #include "llvm/ADT/PointerUnion.h"
@@ -1411,7 +1412,9 @@ public:
   /// and enumerator names preceding any tag name. Note that this
   /// routine will not look into parent contexts.
   lookup_result lookup(DeclarationName Name);
-  lookup_const_result lookup(DeclarationName Name) const;
+  lookup_const_result lookup(DeclarationName Name) const {
+    return const_cast<DeclContext*>(this)->lookup(Name);
+  }
 
   /// \brief A simplistic name lookup mechanism that performs name lookup
   /// into this declaration context without consulting the external source.