diff --git a/src/list.c b/src/list.c
index 1dfaa21..9a348a8 100644
--- a/src/list.c
+++ b/src/list.c
@@ -479,9 +479,7 @@
  * Return FAIL when out of memory.
  */
     int
-list_append_list(list1, list2)
-    list_T	*list1;
-    list_T	*list2;
+list_append_list(list_T *list1, list_T *list2)
 {
     listitem_T	*li = listitem_alloc();