isdst_differ      499 lib/mktime.c     if (isdst_differ (isdst, tm.tm_isdst))
isdst_differ      537 lib/mktime.c                 if (! isdst_differ (isdst, otm.tm_isdst))
isdst_differ      613 lib/mktime.c             | isdst_differ (a->tm_isdst, b->tm_isdst));