diff --git a/src/frame.h b/src/frame.h
index 3c4c9dc08bf..2411341598a 100644
--- a/src/frame.h
+++ b/src/frame.h
@@ -472,6 +472,10 @@ struct frame
 
   /* Set to non-zero when current redisplay has updated frame.  */
   unsigned updated_p : 1;
+
+  /* Set to non-zero to minimize tool-bar height even when
+     auto-resize-tool-bar is set to grow-only.  */
+  unsigned minimize_tool_bar_window_p : 1;
 };
 
 #ifdef MULTI_KBOARD