1 files changed, 1 insertions, 0 deletions
diff --git a/env.h b/env.h
index 388c946933..c47c01d9db 100644
--- a/env.h
+++ b/env.h
@@ -25,6 +25,7 @@ extern struct FRAME {
     struct RNode *node;
     int iter;
     int flags;
+    unsigned long uniq;
 } *ruby_frame;
 
 void rb_gc_mark_frame _((struct FRAME *));