diff --git a/src/structs.h b/src/structs.h
index 330bb53..90e7620 100644
--- a/src/structs.h
+++ b/src/structs.h
@@ -3889,13 +3889,13 @@
  */
 typedef struct
 {
-    buf_T	*save_curbuf;	// saved curbuf
-    int		use_aucmd_win;	// using aucmd_win
-    win_T	*save_curwin;	// saved curwin
-    win_T	*new_curwin;	// new curwin
-    win_T	*save_prevwin;	// saved prevwin
-    bufref_T	new_curbuf;	// new curbuf
-    char_u	*globaldir;	// saved value of globaldir
+    buf_T	*save_curbuf;	    // saved curbuf
+    int		use_aucmd_win;	    // using aucmd_win
+    int		save_curwin_id;	    // ID of saved curwin
+    int		new_curwin_id;	    // ID of new curwin
+    int		save_prevwin_id;    // ID of saved prevwin
+    bufref_T	new_curbuf;	    // new curbuf
+    char_u	*globaldir;	    // saved value of globaldir
 } aco_save_T;
 
 /*