diff --git a/src/screen.c b/src/screen.c
index 08e147d..e9bc792 100644
--- a/src/screen.c
+++ b/src/screen.c
@@ -2696,7 +2696,8 @@
 #endif
 
     entered = FALSE;
-    --RedrawingDisabled;
+    if (RedrawingDisabled > 0)
+	--RedrawingDisabled;
 
     /*
      * Do not apply autocommands more than 3 times to avoid an endless loop
@@ -4496,7 +4497,7 @@
 	return 0;
     else
 #endif
-	return ((!RedrawingDisabled
+	return ((RedrawingDisabled == 0
 #ifdef FEAT_EVAL
 		    || ignore_redraw_flag_for_testing
 #endif