maint: remove useless REPLACE_*_H macros There are still a few modules, like iconv_h.m4, that still use older paradigms where GNULIB_POSIXCHECK is unsupported and where gl_REPLACE_<HEADER>_H is still essential. But since we are moving away from that style, I see no reason to keep the idiom for the modules that don't need it. * m4/arpa_inet_h.m4 (gl_REPLACE_ARPA_INET_H): Delete. * m4/dirent_h.m4 (gl_REPLACE_DIRENT_H): Likewise. * m4/locale_h.m4 (gl_REPLACE_LOCALE_H): Likewise. * m4/poll_h.m4 (gl_REPLACE_POLL_H): Likewise. * m4/spawn_h.m4 (gl_REPLACE_SPAWN_H): Likewise. * m4/sys_ioctl_h.m4 (gl_REPLACE_SYS_IOCTL_H): Likewise. * m4/wchar_h.m4 (gl_REPLACE_WCHAR_H): Likewise. * m4/btowc.m4: Update callers. * m4/dirfd.m4: Likewise. * m4/duplocale.m4: Likewise. * m4/fchdir.m4: Likewise. * m4/fdopendir.m4: Likewise. * m4/inet_ntop.m4: Likewise. * m4/inet_pton.m4: Likewise. * m4/ioctl.m4: Likewise. * m4/mbrlen.m4: Likewise. * m4/mbrtowc.m4: Likewise. * m4/mbsinit.m4: Likewise. * m4/mbsnrtowcs.m4: Likewise. * m4/mbsrtowcs.m4: Likewise. * m4/poll.m4: Likewise. * m4/setlocale.m4: Likewise. * m4/wcrtomb.m4: Likewise. * m4/wcsnrtombs.m4: Likewise. * m4/wcsrtombs.m4: Likewise. * m4/wctob.m4: Likewise. * m4/wcwidth.m4: Likewise. * modules/posix_spawn: Likewise. * modules/posix_spawn_file_actions_addclose: Likewise. * modules/posix_spawn_file_actions_adddup2: Likewise. * modules/posix_spawn_file_actions_addopen: Likewise. * modules/posix_spawn_file_actions_destroy: Likewise. * modules/posix_spawn_file_actions_init: Likewise. * modules/posix_spawnattr_destroy: Likewise. * modules/posix_spawnattr_getflags: Likewise. * modules/posix_spawnattr_getpgroup: Likewise. * modules/posix_spawnattr_getschedparam: Likewise. * modules/posix_spawnattr_getschedpolicy: Likewise. * modules/posix_spawnattr_getsigdefault: Likewise. * modules/posix_spawnattr_getsigmask: Likewise. * modules/posix_spawnattr_init: Likewise. * modules/posix_spawnattr_setflags: Likewise. * modules/posix_spawnattr_setpgroup: Likewise. * modules/posix_spawnattr_setschedparam: Likewise. * modules/posix_spawnattr_setschedpolicy: Likewise. * modules/posix_spawnattr_setsigdefault: Likewise. * modules/posix_spawnattr_setsigmask: Likewise. * modules/posix_spawnp: Likewise. Signed-off-by: Eric Blake <eblake@redhat.com>

# duplocale.m4 serial 6
dnl Copyright (C) 2009-2011 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.

AC_DEFUN([gl_FUNC_DUPLOCALE],
[
  AC_REQUIRE([gl_LOCALE_H_DEFAULTS])
  AC_REQUIRE([AC_CANONICAL_HOST])
  AC_CHECK_FUNCS_ONCE([duplocale])
  if test $ac_cv_func_duplocale = yes; then
    dnl Check against glibc bug where duplocale crashes.
    dnl See <http://sourceware.org/bugzilla/show_bug.cgi?id=10969>.
    dnl Also, on AIX 7.1, duplocale(LC_GLOBAL_LOCALE) returns (locale_t)0 with
    dnl errno set to EINVAL.
    AC_REQUIRE([gl_LOCALE_H])
    AC_CACHE_CHECK([whether duplocale(LC_GLOBAL_LOCALE) works],
      [gl_cv_func_duplocale_works],
      [AC_RUN_IFELSE(
         [AC_LANG_SOURCE([[
#include <locale.h>
#if HAVE_XLOCALE_H
# include <xlocale.h>
#endif
int main ()
{
  if (duplocale (LC_GLOBAL_LOCALE) == (locale_t)0)
    return 1;
  return 0;
}]])],
         [gl_cv_func_duplocale_works=yes],
         [gl_cv_func_duplocale_works=no],
         [dnl Guess it works except on glibc < 2.12, uClibc, and AIX.
          case "$host_os" in
            aix*) gl_cv_func_duplocale_works="guessing no";;
            *-gnu*)
              AC_EGREP_CPP([Unlucky], [
#include <features.h>
#ifdef __GNU_LIBRARY__
 #if (__GLIBC__ == 2 && __GLIBC_MINOR__ < 12)
  Unlucky GNU user
 #endif
#endif
#ifdef __UCLIBC__
 Unlucky user
#endif
                ],
                [gl_cv_func_duplocale_works="guessing no"],
                [gl_cv_func_duplocale_works="guessing yes"])
              ;;
            *) gl_cv_func_duplocale_works="guessing yes";;
          esac
         ])
      ])
    case "$gl_cv_func_duplocale_works" in
      *no) REPLACE_DUPLOCALE=1 ;;
    esac
  else
    HAVE_DUPLOCALE=0
  fi
  if test $REPLACE_DUPLOCALE = 1; then
    AC_LIBOBJ([duplocale])
    gl_PREREQ_DUPLOCALE
  fi
])

# Prerequisites of lib/duplocale.c.
AC_DEFUN([gl_PREREQ_DUPLOCALE],
[
  :
])