Rewrite mktime from scratch for performance, and for correctness
in the presence of leap seconds.
* time/mktime.c (ydhms_tm_diff, not_equal_tm, print_tm, check_result):
New functions.
(LEAP_SECONDS_POSSIBLE, CHAR_BIT, INT_MIN, INT_MAX,
TIME_T_MIN, TIME_T_MAX, TM_YEAR_BASE, EPOCH_YEAR): New macros.
<limits.h>, <stdlib.h>: New #includes.
(main): Support tests with given broken-down value; support benchmarks.
(__mon_lengths, debugging_enabled, printtm, dist_tm, doit,
do_normalization, normalize, BAD_STRUCT_TM, SKIP_VALUE,
<ctype.h>): Remove.
* time/time.h, time/mktime.c (__mktime_internal): New offset arg.
* time/mktime.c (mktime), time/timegm.c (timegm): Use it.
* time/mktime.c (__mon_yday): New variable; replaces `__mon_lengths'.
time/offtime.c (__offtime), time/tzset.c (compute_change): Use it.
* time/offtime.c (__offtime): Remove useless assignment
`tp->tm_isdst = -1'.
* manual/maint.texi: Update credits.
Fri Oct 6 00:28:53 1995 Roland McGrath <roland@churchy.gnu.ai.mit.edu>
* sysdeps/unix/common/readv.S: Moved to sysdeps/unix/bsd.
* sysdeps/unix/common/writev.S: Moved to sysdeps/unix/bsd.
* sysdeps/unix/sysv/linux/readv.c: File removed.
* sysdeps/unix/sysv/linux/writev.c: File removed.
* sysdeps/unix/configure.in: Check for readv and writev syscalls.
* sysdeps/unix/configure.in: If eval doesn't set $unix_srcname,
set it to $unix_syscall instead of $unix_function.
gettext code.
* sysdeps/unix/sysv/linux/sys/param.h: New file.
* sysdeps/unix/sysv/linux/Subdirs: File removed.
* libc-symbols.h (_LIBC): Define to 1, not just empty.
