Update from Gnulib

This incorporates:
2020-07-30 work around some Oracle Studio attribute bugs
2020-07-29 fsusage, regex, stat-size: remove Cray support
2020-07-26 inttypes: remove support for AIX 4
2020-07-26 gettimeofday: remove workaround for Mac OS X 10.0
2020-07-26 don't require gl_LOCALTIME_BUFFER_DEFAULTS
2020-07-26 alloca: remove Cray-2 and Cray Y-MP support
2020-07-26 libgmp: remove dependency on havelib
2020-07-26 libgmp: remove HAVE_GMP, LIB_GMP
2020-07-25 multiarch: prepare for x86_64+arm64 universal in macOS 11
2020-07-25 sigprocmask: small autoconf macro improvement
2020-07-25 small autoconf macro improvements
2020-07-24 timespec: remove dependence on ‘verify’
2020-07-24 optimize a few more three-valued comparisons
2020-07-24 fix _GL_CMP parenthesization typo
2020-07-23 optimize three-valued comparison between integers
2020-07-24 doc: update for Mac OS X 10.13
2020-07-23 fchmodat, lchmod: use /proc on Cygwin
2020-07-21 inttypes: fix PRI*PTR and SCN*PTR on 64-bit native Windows
2020-07-12 libgmp: avoid warning when --without-libgmp is used
2020-07-12 libgmp: link to the correct shared library
* lib/mini-gmp-gnulib.c: Ignore -Wsuggest-attribute=malloc only for
* build-aux/config.guess, build-aux/config.sub:
* build-aux/install-sh, doc/misc/texinfo.tex, lib/c-strcasecmp.c:
* lib/c-strncasecmp.c, lib/fchmodat.c, lib/fsusage.c:
* lib/gettimeofday.c, lib/inttypes.in.h, lib/lchmod.c:
* lib/mini-gmp-gnulib.c, lib/nstrftime.c, lib/regex.h, lib/timespec.h:
* m4/alloca.m4, m4/getgroups.m4, m4/gettimeofday.m4:
* m4/gnulib-common.m4, m4/inttypes.m4, m4/libgmp.m4, m4/mktime.m4:
* m4/multiarch.m4:
Copy from Gnulib.
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.
* src/Makefile.in, test/Makefile.in (LIBGMP):
Rename from LIB_GMP for compatibility with Gnulib.
All uses changed.

m4/gnulib-common.m4

@@ -1,4 +1,4 @@
-# gnulib-common.m4 serial 50
+# gnulib-common.m4 serial 52
 dnl Copyright (C) 2007-2020 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -120,9 +120,14 @@ AC_DEFUN([gl_COMMON_BODY], [
 #endif
 
 /* Avoid __attribute__ ((cold)) on MinGW; see thread starting at
-   <https://lists.gnu.org/r/emacs-devel/2019-04/msg01152.html>. */
+   <https://lists.gnu.org/r/emacs-devel/2019-04/msg01152.html>.
+   Also, Oracle Studio 12.6 requires 'cold' not '__cold__'.  */
 #if _GL_HAS_ATTRIBUTE (cold) && !defined __MINGW32__
-# define _GL_ATTRIBUTE_COLD __attribute__ ((__cold__))
+# ifndef __SUNPRO_C
+#  define _GL_ATTRIBUTE_COLD __attribute__ ((__cold__))
+# else
+#  define _GL_ATTRIBUTE_COLD __attribute__ ((cold))
+# endif
 #else
 # define _GL_ATTRIBUTE_COLD
 #endif
@@ -176,7 +181,8 @@ AC_DEFUN([gl_COMMON_BODY], [
 # define _GL_ATTRIBUTE_LEAF
 #endif
 
-#if _GL_HAS_ATTRIBUTE (may_alias)
+/* Oracle Studio 12.6 mishandles may_alias despite __has_attribute OK.  */
+#if _GL_HAS_ATTRIBUTE (may_alias) && !defined __SUNPRO_C
 # define _GL_ATTRIBUTE_MAY_ALIAS __attribute__ ((__may_alias__))
 #else
 # define _GL_ATTRIBUTE_MAY_ALIAS
@@ -292,6 +298,20 @@ AC_DEFUN([gl_COMMON_BODY], [
        that may clobber errno, it needs to save and restore the value of
        errno.  */
 #define _GL_ASYNC_SAFE
+])
+  AH_VERBATIM([micro_optimizations],
+[/* _GL_CMP (n1, n2) performs a three-valued comparison on n1 vs. n2.
+   It returns
+     1  if n1 > n2
+     0  if n1 == n2
+     -1 if n1 < n2
+   The naïve code   (n1 > n2 ? 1 : n1 < n2 ? -1 : 0)  produces a conditional
+   jump with nearly all GCC versions up to GCC 10.
+   This variant     (n1 < n2 ? -1 : n1 > n2)  produces a conditional with many
+   GCC versions up to GCC 9.
+   The better code  (n1 > n2) - (n1 < n2)  from Hacker's Delight § 2-9
+   avoids conditional jumps in all GCC versions >= 3.4.  */
+#define _GL_CMP(n1, n2) (((n1) > (n2)) - ((n1) < (n2)))
 ])
   dnl Hint which direction to take regarding cross-compilation guesses:
   dnl When a user installs a program on a platform they are not intimately
@@ -612,6 +632,15 @@ AC_DEFUN([gl_BIGENDIAN],
   AC_C_BIGENDIAN
 ])
 
+# gl_SILENT(command)
+# executes command, but without the normal configure output.
+AC_DEFUN([gl_SILENT],
+[
+  {
+    $1
+  } AS_MESSAGE_FD>/dev/null
+])
+
 # gl_CACHE_VAL_SILENT(cache-id, command-to-set-it)
 # is like AC_CACHE_VAL(cache-id, command-to-set-it), except that it does not
 # output a spurious "(cached)" mark in the midst of other configure output.