{
        struct commit *head = lookup_commit_or_die(head_sha1, "HEAD");
        struct commit *branch = lookup_commit_or_die(remote->old_sha1, remote->name);
-       struct commit_list *merge_bases = get_merge_bases(head, branch, 1);
 
-       return (merge_bases && !merge_bases->next && merge_bases->item == branch);
+       return in_merge_bases(branch, head);
 }
 
 static int delete_remote_branch(const char *pattern, int force)