MATCH_ARG_INIT   3782 regexec.c        MATCH_ARG_INIT(msa, option, region, at, at);
MATCH_ARG_INIT   4260 regexec.c            MATCH_ARG_INIT(msa, option, region, start, start);
MATCH_ARG_INIT   4276 regexec.c        MATCH_ARG_INIT(msa, option, region, start, global_pos);