mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-24 07:20:37 +00:00
55 lines
1.8 KiB
Plaintext
55 lines
1.8 KiB
Plaintext
# time_rz.m4
|
|
# serial 2
|
|
dnl Copyright (C) 2015-2024 Free Software Foundation, Inc.
|
|
dnl This file is free software; the Free Software Foundation
|
|
dnl gives unlimited permission to copy and/or distribute it,
|
|
dnl with or without modifications, as long as this notice is preserved.
|
|
|
|
dnl Time zone functions: tzalloc, localtime_rz, etc.
|
|
|
|
dnl Written by Paul Eggert.
|
|
|
|
AC_DEFUN([gl_TIME_RZ],
|
|
[
|
|
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
|
|
AC_REQUIRE([gl_TIME_H_DEFAULTS])
|
|
|
|
# On Mac OS X 10.6, localtime loops forever with some time_t values.
|
|
# See Bug#27706, Bug#27736, and
|
|
# https://lists.gnu.org/r/bug-gnulib/2017-07/msg00142.html
|
|
AC_CACHE_CHECK([whether localtime works even near extrema],
|
|
[gl_cv_func_localtime_works],
|
|
[gl_cv_func_localtime_works=yes
|
|
AC_RUN_IFELSE(
|
|
[AC_LANG_PROGRAM(
|
|
[[#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <time.h>
|
|
]], [[
|
|
time_t t = -67768038400666600;
|
|
struct tm *tm;
|
|
char *tz = getenv ("TZ");
|
|
if (! (tz && strcmp (tz, "QQQ0") == 0))
|
|
return 0;
|
|
alarm (2);
|
|
tm = localtime (&t);
|
|
/* Use TM and *TM to suppress over-optimization. */
|
|
return tm && tm->tm_isdst;
|
|
]])],
|
|
[(TZ=QQQ0 ./conftest$EXEEXT) >/dev/null 2>&1 ||
|
|
gl_cv_func_localtime_works=no],
|
|
[],
|
|
[gl_cv_func_localtime_works="guessing yes"])])
|
|
if test "$gl_cv_func_localtime_works" = no; then
|
|
AC_DEFINE([HAVE_LOCALTIME_INFLOOP_BUG], 1,
|
|
[Define if localtime-like functions can loop forever on
|
|
extreme arguments.])
|
|
fi
|
|
|
|
AC_CHECK_TYPES([timezone_t], [], [], [[#include <time.h>]])
|
|
if test "$ac_cv_type_timezone_t" = yes; then
|
|
HAVE_TIMEZONE_T=1
|
|
fi
|
|
])
|