diff --git a/src/mark.c b/src/mark.c
index e7addbe..ade5a10 100644
--- a/src/mark.c
+++ b/src/mark.c
@@ -1484,7 +1484,7 @@
 {
     buf_T	*buf = NULL;
 
-    if (rettv_list_alloc(rettv) != OK)
+    if (rettv_list_alloc(rettv) == FAIL)
 	return;
 
     if (in_vim9script() && check_for_opt_buffer_arg(argvars, 0) == FAIL)