int quiet = 0;
        int prefixlen = 0;
        struct option options[] = {
-               OPT_BOOLEAN('p', "stdout", &to_stdout, N_("send results to standard output")),
+               OPT_BOOL('p', "stdout", &to_stdout, N_("send results to standard output")),
                OPT_SET_INT(0, "diff3", &xmp.style, N_("use a diff3 based merge"), XDL_MERGE_DIFF3),
                OPT_SET_INT(0, "ours", &xmp.favor, N_("for conflicts, use our version"),
                            XDL_MERGE_FAVOR_OURS),