diff --git a/TAO/TAO_IDL/ast/ast_visitor.cpp b/TAO/TAO_IDL/ast/ast_visitor.cpp
index d90421c3d8201..b7192087fba19 100644
--- a/TAO/TAO_IDL/ast/ast_visitor.cpp
+++ b/TAO/TAO_IDL/ast/ast_visitor.cpp
@@ -18,3 +18,8 @@ int ast_visitor::visit_annotation_decl (AST_Annotation_Decl *)
 {
   return 0;
 }
+
+int ast_visitor::visit_map (AST_Map *);
+{
+  return 0;
+}
diff --git a/TAO/TAO_IDL/include/ast_visitor.h b/TAO/TAO_IDL/include/ast_visitor.h
index e3e3beef1848d..59ea51b7dfbb7 100644
--- a/TAO/TAO_IDL/include/ast_visitor.h
+++ b/TAO/TAO_IDL/include/ast_visitor.h
@@ -134,14 +134,17 @@ class TAO_IDL_FE_Export ast_visitor
   virtual int visit_enum_val (AST_EnumVal *node) = 0;
   virtual int visit_array (AST_Array *node) = 0;
   virtual int visit_sequence (AST_Sequence *node) = 0;
-  virtual int visit_map (AST_Map *node) = 0;
   virtual int visit_string (AST_String *node) = 0;
   virtual int visit_typedef (AST_Typedef *node) = 0;
   virtual int visit_root (AST_Root *node) = 0;
   virtual int visit_native (AST_Native *node) = 0;
   virtual int visit_valuebox (AST_ValueBox *node) = 0;
+
+  // These are implemented as nops for backwards compatibility. New node types
+  // should go here.
   virtual int visit_fixed (AST_Fixed *node);
   virtual int visit_annotation_decl (AST_Annotation_Decl *node);
+  virtual int visit_map (AST_Map *node);
 
 protected:
   // For abstract class.