static int opt_parse_rename_score(const struct option *opt, const char *arg, int unset)
 {
        const char **value = opt->value;
+
+       BUG_ON_OPT_NEG(unset);
+
        if (arg != NULL && *arg == '=')
                arg = arg + 1;
 
        if (status_format != STATUS_FORMAT_PORCELAIN &&
            status_format != STATUS_FORMAT_PORCELAIN_V2)
                progress_flag = REFRESH_PROGRESS;
-       read_index_preload(&the_index, &s.pathspec, progress_flag);
+       read_index(&the_index);
        refresh_index(&the_index,
                      REFRESH_QUIET|REFRESH_UNMERGED|progress_flag,
                      &s.pathspec, NULL, NULL);