At least busybox's cron implements it that way:
if (line->cl_Mins[ptm->tm_min] && line->cl_Hrs[ptm->tm_hour] && (line->cl_Days[ptm->tm_mday] || line->cl_Dow[ptm->tm_wday]) && line->cl_Mons[ptm->tm_mon] ) {
But first I‘d check the behavior of other crons ;-)
At least busybox's cron implements it that way: