1dnl A placeholder for POSIX 2008 <stddef.h>, for platforms that have issues.
2# stddef_h.m4 serial 4
3dnl Copyright (C) 2009-2012 Free Software Foundation, Inc.
4dnl This file is free software; the Free Software Foundation
5dnl gives unlimited permission to copy and/or distribute it,
6dnl with or without modifications, as long as this notice is preserved.
7
8AC_DEFUN([gl_STDDEF_H],
9[
10  AC_REQUIRE([gl_STDDEF_H_DEFAULTS])
11  AC_REQUIRE([gt_TYPE_WCHAR_T])
12  STDDEF_H=
13  if test $gt_cv_c_wchar_t = no; then
14    HAVE_WCHAR_T=0
15    STDDEF_H=stddef.h
16  fi
17  AC_CACHE_CHECK([whether NULL can be used in arbitrary expressions],
18    [gl_cv_decl_null_works],
19    [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stddef.h>
20      int test[2 * (sizeof NULL == sizeof (void *)) -1];
21]])],
22      [gl_cv_decl_null_works=yes],
23      [gl_cv_decl_null_works=no])])
24  if test $gl_cv_decl_null_works = no; then
25    REPLACE_NULL=1
26    STDDEF_H=stddef.h
27  fi
28  AC_SUBST([STDDEF_H])
29  AM_CONDITIONAL([GL_GENERATE_STDDEF_H], [test -n "$STDDEF_H"])
30  if test -n "$STDDEF_H"; then
31    gl_NEXT_HEADERS([stddef.h])
32  fi
33])
34
35AC_DEFUN([gl_STDDEF_MODULE_INDICATOR],
36[
37  dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
38  AC_REQUIRE([gl_STDDEF_H_DEFAULTS])
39  gl_MODULE_INDICATOR_SET_VARIABLE([$1])
40])
41
42AC_DEFUN([gl_STDDEF_H_DEFAULTS],
43[
44  dnl Assume proper GNU behavior unless another module says otherwise.
45  REPLACE_NULL=0;                AC_SUBST([REPLACE_NULL])
46  HAVE_WCHAR_T=1;                AC_SUBST([HAVE_WCHAR_T])
47])
48