assert(cb_data == NULL);
 
        if (starts_with(refname, "refs/replace/")) {
-               unsigned char original_sha1[20];
+               struct object_id original_oid;
                if (!check_replace_refs)
                        return 0;
-               if (get_sha1_hex(refname + 13, original_sha1)) {
+               if (get_oid_hex(refname + 13, &original_oid)) {
                        warning("invalid replace ref %s", refname);
                        return 0;
                }
-               obj = parse_object(original_sha1);
+               obj = parse_object(original_oid.hash);
                if (obj)
                        add_name_decoration(DECORATION_GRAFTED, "replaced", obj);
                return 0;