Update from Gnulib

This incorporates:
2018-09-10 timespec: fix resolution confusion
2018-09-09 mktime: simplify in prep for glibc merge
2018-09-07 intprops: minor clarification of code
2018-09-06 stddef: Override max_align_t on NetBSD 8.0/x86
2018-09-06 fcntl: Fix F_DUPFD_CLOEXEC behaviour on Haiku
2018-09-06 strtoll, strtoull: Rely on limits-h module
2018-09-06 limits-h: Provide numerical limits macros
2018-09-06 fcntl: Don't access nonexistent optional argument
2018-09-02 mktime: fix unlikely race+overflow bug
2018-08-31 mktime, timegm: simplify glibc time64_t
2018-08-31 mktime, timegm: simplify merge to glibc
* build-aux/config.guess, build-aux/config.sub:
* lib/dtotimespec.c, lib/fcntl.c, lib/intprops.h:
* lib/limits.in.h, lib/mktime-internal.h, lib/mktime.c:
* lib/stat-time.h, lib/strtol.c, lib/timegm.c:
* lib/timespec-add.c, lib/timespec-sub.c, lib/timespec.h:
* lib/utimens.c, m4/limits-h.m4, m4/stddef_h.m4:
Copy from Gnulib.

2 files changed, 35 insertions, 10 deletions

diff --git a/m4/limits-h.m4 b/m4/limits-h.m4
index 83886634396..3a2cd91ead0 100644
--- a/m4/limits-h.m4
+++ b/m4/limits-h.m4
@@ -11,14 +11,18 @@ AC_DEFUN_ONCE([gl_LIMITS_H],
 [
   gl_CHECK_NEXT_HEADERS([limits.h])
 
-  AC_CACHE_CHECK([whether limits.h has ULLONG_WIDTH etc.],
+  AC_CACHE_CHECK([whether limits.h has LLONG_MAX, WORD_BIT, ULLONG_WIDTH etc.],
     [gl_cv_header_limits_width],
     [AC_COMPILE_IFELSE(
-       [AC_LANG_PROGRAM([[#ifndef __STDC_WANT_IEC_60559_BFP_EXT__
-                           #define __STDC_WANT_IEC_60559_BFP_EXT__ 1
-                          #endif
-                          #include <limits.h>
-                          int ullw = ULLONG_WIDTH;]])],
+       [AC_LANG_PROGRAM(
+          [[#ifndef __STDC_WANT_IEC_60559_BFP_EXT__
+             #define __STDC_WANT_IEC_60559_BFP_EXT__ 1
+            #endif
+            #include <limits.h>
+            long long llm = LLONG_MAX;
+            int wb = WORD_BIT;
+            int ullw = ULLONG_WIDTH;
+          ]])],
        [gl_cv_header_limits_width=yes],
        [gl_cv_header_limits_width=no])])
   if test "$gl_cv_header_limits_width" = yes; then
diff --git a/m4/stddef_h.m4 b/m4/stddef_h.m4
index ba3d201cf37..07b040abdf1 100644
--- a/m4/stddef_h.m4
+++ b/m4/stddef_h.m4
@@ -1,5 +1,5 @@
 dnl A placeholder for <stddef.h>, for platforms that have issues.
-# stddef_h.m4 serial 5
+# stddef_h.m4 serial 6
 dnl Copyright (C) 2009-2018 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -10,13 +10,33 @@ AC_DEFUN([gl_STDDEF_H],
   AC_REQUIRE([gl_STDDEF_H_DEFAULTS])
   AC_REQUIRE([gt_TYPE_WCHAR_T])
   STDDEF_H=
-  AC_CHECK_TYPE([max_align_t], [], [HAVE_MAX_ALIGN_T=0; STDDEF_H=stddef.h],
-    [[#include <stddef.h>
-    ]])
+
+  dnl Test whether the type max_align_t exists and whether its alignment
+  dnl "is as great as is supported by the implementation in all contexts".
+  AC_CACHE_CHECK([for good max_align_t],
+    [gl_cv_type_max_align_t],
+    [AC_COMPILE_IFELSE(
+       [AC_LANG_PROGRAM(
+          [[#include <stddef.h>
+            unsigned int s = sizeof (max_align_t);
+            #if defined __GNUC__ || defined __IBM__ALIGNOF__
+            int check1[2 * (__alignof__ (double) <= __alignof__ (max_align_t)) - 1];
+            int check2[2 * (__alignof__ (long double) <= __alignof__ (max_align_t)) - 1];
+            #endif
+          ]])],
+       [gl_cv_type_max_align_t=yes],
+       [gl_cv_type_max_align_t=no])
+    ])
+  if test $gl_cv_type_max_align_t = no; then
+    HAVE_MAX_ALIGN_T=0
+    STDDEF_H=stddef.h
+  fi
+
   if test $gt_cv_c_wchar_t = no; then
     HAVE_WCHAR_T=0
     STDDEF_H=stddef.h
   fi
+
   AC_CACHE_CHECK([whether NULL can be used in arbitrary expressions],
     [gl_cv_decl_null_works],
     [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stddef.h>
@@ -28,6 +48,7 @@ AC_DEFUN([gl_STDDEF_H],
     REPLACE_NULL=1
     STDDEF_H=stddef.h
   fi
+
   AC_SUBST([STDDEF_H])
   AM_CONDITIONAL([GL_GENERATE_STDDEF_H], [test -n "$STDDEF_H"])
   if test -n "$STDDEF_H"; then