Update from Gnulib

This incorporates:
2018-11-03 nstrftime: simplify test for mktime failure
2018-11-02 gnulib-common.m4: port _Noreturn to C++
2018-10-22 std-gnu11: Support Autoconf versions < 2.64
2018-10-22 Assume Autoconf >= 2.63
2018-10-16 Remove support for Ultrix
2018-10-16 getloadavg: Remove support for ConvexOS
2018-10-16 getloadavg: Remove support for Sony NEWS
2018-10-16 Remove support for Dynix/ptx
2018-10-16 fsusage: Remove support for AIX 3
2018-10-16 fsusage, stat-size, getloadavg: Remove support for AIX PS/2
2018-10-16 getloadavg: Remove support for HP-UX on m68k
2018-10-16 fsusage, mountlist: Remove support for DolphinOS
2018-10-16 getloadavg: Remove support for Alliant FX/2800
2018-10-16 getloadavg: Remove support for tek4300
2018-10-16 getloadavg: Remove support for Ardent
* build-aux/config.guess, build-aux/config.sub, lib/_Noreturn.h:
* lib/fsusage.c, lib/getgroups.c, lib/getloadavg.c:
* lib/nstrftime.c, lib/time.in.h, m4/errno_h.m4:
* m4/fsusage.m4, m4/getgroups.m4, m4/gnulib-common.m4, m4/longlong.m4:
* m4/std-gnu11.m4, m4/stdint.m4:
Copy from Gnulib.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate:

1 files changed, 2 insertions, 20 deletions

diff --git a/lib/nstrftime.c b/lib/nstrftime.c
index 46e806e6049..1dd49c0f782 100644
--- a/lib/nstrftime.c
+++ b/lib/nstrftime.c
@@ -1438,28 +1438,10 @@ __strftime_internal (STREAM_OR_CHAR_T *s, STRFTIME_ARG (size_t maxsize)
 # endif
 
                 ltm = *tp;
+                ltm.tm_wday = -1;
                 lt = mktime_z (tz, &ltm);
-
-                if (lt == (time_t) -1)
-                  {
-                    /* mktime returns -1 for errors, but -1 is also a
-                       valid time_t value.  Check whether an error really
-                       occurred.  */
-                    struct tm tm;
-
-                    if (! localtime_rz (tz, &lt, &tm)
-                        || ((ltm.tm_sec ^ tm.tm_sec)
-                            | (ltm.tm_min ^ tm.tm_min)
-                            | (ltm.tm_hour ^ tm.tm_hour)
-                            | (ltm.tm_mday ^ tm.tm_mday)
-                            | (ltm.tm_mon ^ tm.tm_mon)
-                            | (ltm.tm_year ^ tm.tm_year)))
-                      break;
-                  }
-
-                if (! localtime_rz (0, &lt, &gtm))
+                if (ltm.tm_wday < 0 || ! localtime_rz (0, &lt, &gtm))
                   break;
-
                 diff = tm_diff (&ltm, &gtm);
               }
 #endif