1# wmemchr.m4 serial 4
2dnl Copyright (C) 2011-2020 Free Software Foundation, Inc.
3dnl This file is free software; the Free Software Foundation
4dnl gives unlimited permission to copy and/or distribute it,
5dnl with or without modifications, as long as this notice is preserved.
6
7AC_DEFUN([gl_FUNC_WMEMCHR],
8[
9  AC_REQUIRE([gl_WCHAR_H_DEFAULTS])
10  dnl We cannot use AC_CHECK_FUNCS here, because the MSVC 9 header files
11  dnl provide this function as an inline function definition.
12  AC_CACHE_CHECK([for wmemchr], [gl_cv_func_wmemchr],
13    [AC_LINK_IFELSE(
14       [AC_LANG_PROGRAM([[
15/* Tru64 with Desktop Toolkit C has a bug: <stdio.h> must be included before
16   <wchar.h>.
17   BSD/OS 4.0.1 has a bug: <stddef.h>, <stdio.h> and <time.h> must be included
18   before <wchar.h>.  */
19#include <stddef.h>
20#include <stdio.h>
21#include <time.h>
22#include <wchar.h>
23]],
24          [[return ! wmemchr ((const wchar_t *) 0, (wchar_t) ' ', 0);]])
25       ],
26       [gl_cv_func_wmemchr=yes],
27       [gl_cv_func_wmemchr=no])
28    ])
29  if test $gl_cv_func_wmemchr = no; then
30    HAVE_WMEMCHR=0
31  fi
32])
33