Update from Gnulib

This incorporates:
2020-08-16 time_rz: remove unused functions
2020-08-16 time_rz: fix issues with mktime_z failures
2020-08-16 nstrftime: Guide inlining also on clang
2020-08-16 intprops: Avoid bogus warning on clang
2020-08-16 libc-config: Enable __REDIRECT macro also on clang
2020-08-16 regex: Use initializer shorthand syntax also with clang
2020-08-16 regex: Use space optimization also with clang
2020-08-16 Use _Static_assert and static_assert when present on clang
2020-08-16 Use 'throw ()' for optimization in C++ mode also on clang
2020-08-16 stdio: Don't break attribute 'scanf' on clang
2020-08-16 Fix "warning: 'format' attribute ...: rpl_printf"
2020-08-16 Fix "warning: attribute declaration must precede definition"
2020-08-16 Fix undesired warnings
2020-08-16 Don't use Autoconf quadrigraphsxo
2020-08-16 Fix quoting of AC_LANG_PROGRAM arguments
2020-08-16 Assume autoconf >= 2.64
2020-08-15 nstrftime: be more predictable about errno
2020-08-15 canonicalize: Fix autoconf test on MSVC/clang
2020-08-15 Support compiling without -loldnames on native Windows
2020-08-14 mktime, mktime-internal: Remove obsolete code
2020-08-14 Assume tzset exists
* lib/c++defs.h, lib/canonicalize-lgpl.c, lib/cdefs.h, lib/dup2.c:
* lib/fcntl.in.h, lib/getopt-cdefs.in.h, lib/intprops.h, lib/md5.h:
* lib/mktime.c, lib/nstrftime.c, lib/open.c, lib/regcomp.c:
* lib/regex_internal.h, lib/stdio.in.h, lib/stdlib.in.h:
* lib/strftime.h, lib/string.in.h, lib/sys_select.in.h:
* lib/sys_stat.in.h, lib/sys_time.in.h, lib/time.in.h, lib/time_rz.c:
* lib/unistd.in.h, lib/verify.h, m4/00gnulib.m4:
* m4/absolute-header.m4, m4/alloca.m4, m4/canonicalize.m4, m4/dup2.m4:
* m4/fchmodat.m4, m4/fcntl.m4, m4/fdopendir.m4, m4/fpending.m4:
* m4/futimens.m4, m4/getdtablesize.m4, m4/getloadavg.m4:
* m4/gnulib-common.m4, m4/include_next.m4, m4/largefile.m4:
* m4/manywarnings.m4, m4/mktime.m4, m4/nstrftime.m4, m4/open-slash.m4:
* m4/pselect.m4, m4/pthread_sigmask.m4, m4/time_h.m4, m4/utimens.m4:
* m4/utimensat.m4, m4/utimes.m4, m4/warnings.m4:
Copy from Gnulib.
* lib/gnulib.mk.in: Regenerate.

1 files changed, 17 insertions, 34 deletions

diff --git a/lib/time_rz.c b/lib/time_rz.c
index 5d85963c9ed..95438cf876e 100644
--- a/lib/time_rz.c
+++ b/lib/time_rz.c
@@ -54,31 +54,6 @@ enum { ABBR_SIZE_MIN = DEFAULT_MXFAST - offsetof (struct tm_zone, abbrs) };
    matters; the pointer is never dereferenced.  */
 static timezone_t const local_tz = (timezone_t) 1;
 
-#if HAVE_TM_ZONE || HAVE_TZNAME
-
-/* Return true if the values A and B differ according to the rules for
-   tm_isdst: A and B differ if one is zero and the other positive.  */
-static bool
-isdst_differ (int a, int b)
-{
-  return !a != !b && 0 <= a && 0 <= b;
-}
-
-/* Return true if A and B are equal.  */
-static int
-equal_tm (const struct tm *a, const struct tm *b)
-{
-  return ! ((a->tm_sec ^ b->tm_sec)
-            | (a->tm_min ^ b->tm_min)
-            | (a->tm_hour ^ b->tm_hour)
-            | (a->tm_mday ^ b->tm_mday)
-            | (a->tm_mon ^ b->tm_mon)
-            | (a->tm_year ^ b->tm_year)
-            | isdst_differ (a->tm_isdst, b->tm_isdst));
-}
-
-#endif
-
 /* Copy to ABBRS the abbreviation at ABBR with size ABBR_SIZE (this
    includes its trailing null byte).  Append an extra null byte to
    mark the end of ABBRS.  */
@@ -327,17 +302,25 @@ mktime_z (timezone_t tz, struct tm *tm)
       timezone_t old_tz = set_tz (tz);
       if (old_tz)
         {
-          time_t t = mktime (tm);
-#if HAVE_TM_ZONE || HAVE_TZNAME
-          time_t badtime = -1;
           struct tm tm_1;
-          if ((t != badtime
-               || (localtime_r (&t, &tm_1) && equal_tm (tm, &tm_1)))
-              && !save_abbr (tz, tm))
-            t = badtime;
+          tm_1.tm_sec = tm->tm_sec;
+          tm_1.tm_min = tm->tm_min;
+          tm_1.tm_hour = tm->tm_hour;
+          tm_1.tm_mday = tm->tm_mday;
+          tm_1.tm_mon = tm->tm_mon;
+          tm_1.tm_year = tm->tm_year;
+          tm_1.tm_yday = -1;
+          tm_1.tm_isdst = tm->tm_isdst;
+          time_t t = mktime (&tm_1);
+          bool ok = 0 <= tm_1.tm_yday;
+#if HAVE_TM_ZONE || HAVE_TZNAME
+          ok = ok && save_abbr (tz, &tm_1);
 #endif
-          if (revert_tz (old_tz))
-            return t;
+          if (revert_tz (old_tz) && ok)
+            {
+              *tm = tm_1;
+              return t;
+            }
         }
       return -1;
     }