diff --git a/src/fix_enforce2d.h b/src/fix_enforce2d.h
index cdead78f6a0755daa47bdf740ba3962ee95a602d..a3f79309dccd2f9b83d4f2ef02f4b311af7c40b7 100644
--- a/src/fix_enforce2d.h
+++ b/src/fix_enforce2d.h
@@ -36,7 +36,7 @@ class FixEnforce2D : public Fix {
   void post_force_respa(int, int, int);
   void min_post_force(int);
 
- private:
+ protected:
   int nfixlist;
   class Fix **flist;
 };