1dnl A placeholder for <stddef.h>, for platforms that have issues.
2# stddef_h.m4 serial 5
3dnl Copyright (C) 2009-2015 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  AC_CHECK_TYPE([max_align_t], [], [HAVE_MAX_ALIGN_T=0; STDDEF_H=stddef.h],
14    [[#include <stddef.h>
15    ]])
16  if test $gt_cv_c_wchar_t = no; then
17    HAVE_WCHAR_T=0
18    STDDEF_H=stddef.h
19  fi
20  AC_CACHE_CHECK([whether NULL can be used in arbitrary expressions],
21    [gl_cv_decl_null_works],
22    [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <stddef.h>
23      int test[2 * (sizeof NULL == sizeof (void *)) -1];
24]])],
25      [gl_cv_decl_null_works=yes],
26      [gl_cv_decl_null_works=no])])
27  if test $gl_cv_decl_null_works = no; then
28    REPLACE_NULL=1
29    STDDEF_H=stddef.h
30  fi
31  AC_SUBST([STDDEF_H])
32  AM_CONDITIONAL([GL_GENERATE_STDDEF_H], [test -n "$STDDEF_H"])
33  if test -n "$STDDEF_H"; then
34    gl_NEXT_HEADERS([stddef.h])
35  fi
36])
37
38AC_DEFUN([gl_STDDEF_MODULE_INDICATOR],
39[
40  dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
41  AC_REQUIRE([gl_STDDEF_H_DEFAULTS])
42  gl_MODULE_INDICATOR_SET_VARIABLE([$1])
43])
44
45AC_DEFUN([gl_STDDEF_H_DEFAULTS],
46[
47  dnl Assume proper GNU behavior unless another module says otherwise.
48  REPLACE_NULL=0;                AC_SUBST([REPLACE_NULL])
49  HAVE_MAX_ALIGN_T=1;            AC_SUBST([HAVE_MAX_ALIGN_T])
50  HAVE_WCHAR_T=1;                AC_SUBST([HAVE_WCHAR_T])
51])
52