Don't invoke localtime_r or gmtime_r unless it's the GNU C library's localtime_r and gmtime_r; there are too many buggy implementations of localtime_r and gmtime_r out there, and it's not worth keeping track of all the different bugs. * mktime.c (__EXTENSIONS__, HAVE_LOCALTIME_R): Remove. (my_mktime_localtime_r): Renamed from localtime_r; all uses changed. Base it on localtime unless _LIBC.