diff --git a/builtin/revert.c b/builtin/revert.c
index 8b452e810e..8409f4c886 100644
--- a/builtin/revert.c
+++ b/builtin/revert.c
@@ -664,8 +664,8 @@ static void read_and_refresh_cache(struct replay_opts *opts)
  *     assert(commit_list_count(list) == 2);
  *     return list;
  */
-struct commit_list **commit_list_append(struct commit *commit,
-					struct commit_list **next)
+static struct commit_list **commit_list_append(struct commit *commit,
+					       struct commit_list **next)
 {
 	struct commit_list *new = xmalloc(sizeof(struct commit_list));
 	new->item = commit;