Index: include/clang/AST/DeclBase.h
===================================================================
--- include/clang/AST/DeclBase.h
+++ include/clang/AST/DeclBase.h
@@ -949,7 +949,7 @@
   /// \brief Determine whether this is a block-scope declaration with linkage.
   /// This will either be a local variable declaration declared 'extern', or a
   /// local function declaration.
-  bool isLocalExternDecl() {
+  bool isLocalExternDecl() const {
     return IdentifierNamespace & IDNS_LocalExtern;
   }