Merge from gnulib

This incorporates:
2015-10-18 stdalign: work around pre-4.9 GCC x86 bug
2015-10-18 time_rz: avoid warning from bleeding-edge gcc's -Wnonnull
* doc/misc/texinfo.tex, lib/stdalign.in.h, lib/time_rz.c:
Copy from gnulib.

2 files changed, 7 insertions, 7 deletions

diff --git a/lib/stdalign.in.h b/lib/stdalign.in.h
index c6115b6dbe0..ce1e793e273 100644
--- a/lib/stdalign.in.h
+++ b/lib/stdalign.in.h
@@ -52,7 +52,10 @@
 #undef _Alignas
 #undef _Alignof
 
-#if !defined __STDC_VERSION__ || __STDC_VERSION__ < 201112
+/* GCC releases before GCC 4.9 had a bug in _Alignof.  See GCC bug 52023
+   <http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52023>.  */
+#if (!defined __STDC_VERSION__ || __STDC_VERSION__ < 201112 \
+     || (defined __GNUC__ && __GNUC__ < 4 + (__GNUC_MINOR__ < 9)))
 # ifdef __cplusplus
 #  if 201103 <= __cplusplus
 #   define _Alignof(type) alignof (type)
diff --git a/lib/time_rz.c b/lib/time_rz.c
index f94893aa2c1..a89b7e70f14 100644
--- a/lib/time_rz.c
+++ b/lib/time_rz.c
@@ -90,8 +90,7 @@ extend_abbrs (char *abbrs, char const *abbr, size_t abbr_size)
 }
 
 /* Return a newly allocated time zone for NAME, or NULL on failure.
-   As a special case, return a nonzero constant for wall clock time, a
-   constant that survives freeing.  */
+   A null NAME stands for wall clock time (which is like unset TZ).  */
 timezone_t
 tzalloc (char const *name)
 {
@@ -288,10 +287,8 @@ localtime_rz (timezone_t tz, time_t const *t, struct tm *tm)
       timezone_t old_tz = set_tz (tz);
       if (old_tz)
         {
-          tm = localtime_r (t, tm);
-          if (tm && !save_abbr (tz, tm))
-            tm = NULL;
-          if (revert_tz (old_tz))
+          bool abbr_saved = localtime_r (t, tm) && save_abbr (tz, tm);
+          if (revert_tz (old_tz) && abbr_saved)
             return tm;
         }
       return NULL;