Update from gnulib

This incorporates:
2020-01-10 fix major regression from 2020-01-04
2020-01-05 tests: avoid GCC over-optimization
2020-01-04 fix AC_CHECK_DECL so it deactivates clang's built-ins
2020-01-03 getopt-posix: fix compilation failure in testdirs
2020-01-03 doc: mention the 64-bit inode number problem
2020-01-02 wchar: make the HP-UX workaround work on HP-UX 11.31
* build-aux/config.guess, build-aux/config.sub, lib/inttypes.in.h:
* lib/stdlib.in.h, lib/unistd.in.h, m4/00gnulib.m4, m4/largefile.m4:
* m4/unistd_h.m4: Copy from Gnulib
* lib/gnulib.mk.in, m4/gnulib-comp.m4: Regenerate.

4 files changed, 73 insertions, 5 deletions

diff --git a/m4/00gnulib.m4 b/m4/00gnulib.m4
index 1a1a1d74f7e..58bc4efb9c5 100644
--- a/m4/00gnulib.m4
+++ b/m4/00gnulib.m4
@@ -1,13 +1,14 @@
-# 00gnulib.m4 serial 3
+# 00gnulib.m4 serial 5
 dnl Copyright (C) 2009-2020 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
 dnl This file must be named something that sorts before all other
-dnl gnulib-provided .m4 files.  It is needed until such time as we can
-dnl assume Autoconf 2.64, with its improved AC_DEFUN_ONCE and
-dnl m4_divert semantics.
+dnl gnulib-provided .m4 files.  The first part is needed until such time
+dnl as we can assume Autoconf 2.64, with its improved AC_DEFUN_ONCE and
+dnl m4_divert semantics.  The second part is needed until the clang fix
+dnl has been included in Autoconf.
 
 # Until autoconf 2.63, handling of the diversion stack required m4_init
 # to be called first; but this does not happen with aclocal.  Wrapping
@@ -39,6 +40,67 @@ m4_version_prereq([2.63.263], [],
       [m4_indir([_gl_DEFUN_ONCE([$1])])])])]dnl
 [AC][_DEFUN([_gl_DEFUN_ONCE([$1])], [$2])])])
 
+# The following definitions arrange to use a compiler option
+# -Werror=implicit-function-declaration in AC_CHECK_DECL, when the
+# compiler is clang.  Without it, clang implicitly declares "known"
+# library functions in C mode, but not in C++ mode, which would cause
+# Gnulib to omit a declaration and thus later produce an error in C++
+# mode.  As of clang 9.0, these "known" functions are identified through
+# LIBBUILTIN invocations in the LLVM source file
+# llvm/tools/clang/include/clang/Basic/Builtins.def.
+AC_DEFUN([gl_COMPILER_CLANG],
+[
+  AC_REQUIRE([AC_PROG_CC])
+  AC_CACHE_CHECK([whether the compiler is clang],
+    [gl_cv_compiler_clang],
+    [AC_EGREP_CPP([barfbarf],[
+#ifdef __clang__
+barfbarf
+#endif
+       ],
+       [gl_cv_compiler_clang=yes],
+       [gl_cv_compiler_clang=no])
+    ])
+])
+AC_DEFUN_ONCE([gl_COMPILER_PREPARE_CHECK_DECL],
+[
+  AC_REQUIRE([AC_PROG_CC])
+  AC_REQUIRE([gl_COMPILER_CLANG])
+  AC_CACHE_CHECK([for compiler option needed when checking for declarations],
+    [gl_cv_compiler_check_decl_option],
+    [if test $gl_cv_compiler_clang = yes; then
+       dnl Test whether the compiler supports the option
+       dnl '-Werror=implicit-function-declaration'.
+       save_ac_compile="$ac_compile"
+       ac_compile="$ac_compile -Werror=implicit-function-declaration"
+       AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[]],[[]])],
+         [gl_cv_compiler_check_decl_option='-Werror=implicit-function-declaration'],
+         [gl_cv_compiler_check_decl_option=none])
+       ac_compile="$save_ac_compile"
+     else
+       gl_cv_compiler_check_decl_option=none
+     fi
+    ])
+  if test "x$gl_cv_compiler_check_decl_option" != xnone; then
+    ac_compile_for_check_decl="$ac_compile $gl_cv_compiler_check_decl_option"
+  else
+    ac_compile_for_check_decl="$ac_compile"
+  fi
+])
+dnl Redefine _AC_CHECK_DECL_BODY so that it references ac_compile_for_check_decl
+dnl instead of ac_compile.
+m4_define([_AC_CHECK_DECL_BODY],
+[  ac_save_ac_compile="$ac_compile"
+  ac_compile="$ac_compile_for_check_decl"]
+m4_defn([_AC_CHECK_DECL_BODY])[  ac_compile="$ac_save_ac_compile"
+])
+  ])
+dnl Redefine AC_CHECK_DECL so that it starts with an invocation of
+dnl gl_COMPILER_PREPARE_CHECK_DECL.
+m4_define([AC_CHECK_DECL],
+  [gl_COMPILER_PREPARE_CHECK_DECL dnl
+]m4_defn([AC_CHECK_DECL]))
+
 # gl_00GNULIB
 # -----------
 # Witness macro that this file has been included.  Needed to force
diff --git a/m4/gnulib-comp.m4 b/m4/gnulib-comp.m4
index 85a60569326..abaca719024 100644
--- a/m4/gnulib-comp.m4
+++ b/m4/gnulib-comp.m4
@@ -303,6 +303,7 @@ AC_DEFUN([gl_INIT],
     GNULIB_GL_UNISTD_H_GETOPT=1
   fi
   AC_SUBST([GNULIB_GL_UNISTD_H_GETOPT])
+  gl_UNISTD_MODULE_INDICATOR([getopt-posix])
   gl_GETTIME
   gl_FUNC_GETTIMEOFDAY
   if test $HAVE_GETTIMEOFDAY = 0 || test $REPLACE_GETTIMEOFDAY = 1; then
diff --git a/m4/largefile.m4 b/m4/largefile.m4
index 40b16bc0e54..e381339c40c 100644
--- a/m4/largefile.m4
+++ b/m4/largefile.m4
@@ -1,4 +1,5 @@
 # Enable large files on systems where this is not the default.
+# Enable support for files on Linux file systems with 64-bit inode numbers.
 
 # Copyright 1992-1996, 1998-2020 Free Software Foundation, Inc.
 # This file is free software; the Free Software Foundation
@@ -73,6 +74,9 @@ rm -rf conftest*[]dnl
 # one must use special compiler options to get large-file access to work.
 # For more details about this brain damage please see:
 # http://www.unix.org/version2/whatsnew/lfs20mar.html
+# Additionally, on Linux file systems with 64-bit inodes a file that happens
+# to have a 64-bit inode number cannot be accessed by 32-bit applications on
+# Linux x86/x86_64.  This can occur with file systems such as XFS and NFS.
 AC_DEFUN([AC_SYS_LARGEFILE],
 [AC_ARG_ENABLE(largefile,
                [  --disable-largefile     omit support for large files])
diff --git a/m4/unistd_h.m4 b/m4/unistd_h.m4
index 7453866df84..ea2bb016dbb 100644
--- a/m4/unistd_h.m4
+++ b/m4/unistd_h.m4
@@ -1,4 +1,4 @@
-# unistd_h.m4 serial 76
+# unistd_h.m4 serial 77
 dnl Copyright (C) 2006-2020 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -84,6 +84,7 @@ AC_DEFUN([gl_UNISTD_H_DEFAULTS],
   GNULIB_GETHOSTNAME=0;          AC_SUBST([GNULIB_GETHOSTNAME])
   GNULIB_GETLOGIN=0;             AC_SUBST([GNULIB_GETLOGIN])
   GNULIB_GETLOGIN_R=0;           AC_SUBST([GNULIB_GETLOGIN_R])
+  GNULIB_GETOPT_POSIX=0;         AC_SUBST([GNULIB_GETOPT_POSIX])
   GNULIB_GETPAGESIZE=0;          AC_SUBST([GNULIB_GETPAGESIZE])
   GNULIB_GETPASS=0;              AC_SUBST([GNULIB_GETPASS])
   GNULIB_GETUSERSHELL=0;         AC_SUBST([GNULIB_GETUSERSHELL])