1  /* Test of <stddef.h> substitute.
       2     Copyright (C) 2009-2022 Free Software Foundation, Inc.
       3  
       4     This program is free software: you can redistribute it and/or modify
       5     it under the terms of the GNU General Public License as published by
       6     the Free Software Foundation, either version 3 of the License, or
       7     (at your option) any later version.
       8  
       9     This program is distributed in the hope that it will be useful,
      10     but WITHOUT ANY WARRANTY; without even the implied warranty of
      11     MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
      12     GNU General Public License for more details.
      13  
      14     You should have received a copy of the GNU General Public License
      15     along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
      16  
      17  /* Written by Eric Blake <ebb9@byu.net>, 2009.  */
      18  
      19  #include <config.h>
      20  
      21  #include <stddef.h>
      22  #include <limits.h>
      23  #include <stdalign.h>
      24  
      25  /* Check that appropriate types are defined.  */
      26  wchar_t a = 'c';
      27  ptrdiff_t b = 1;
      28  size_t c = 2;
      29  max_align_t x;
      30  
      31  /* Check that NULL can be passed through varargs as a pointer type,
      32     per POSIX 2008.  */
      33  static_assert (sizeof NULL == sizeof (void *));
      34  
      35  /* Check that offsetof produces integer constants with correct type.  */
      36  struct d
      37  {
      38    char e;
      39    char f;
      40  };
      41  /* Solaris 10 has a bug where offsetof is under-parenthesized, and
      42     cannot be used as an arbitrary expression.  However, since it is
      43     unlikely to bite real code, we ignore that short-coming.  */
      44  /* static_assert (sizeof offsetof (struct d, e) == sizeof (size_t)); */
      45  static_assert (sizeof (offsetof (struct d, e)) == sizeof (size_t));
      46  static_assert (offsetof (struct d, f) == 1);
      47  
      48  /* offsetof promotes to an unsigned integer if and only if sizes do
      49     not fit in int.  */
      50  static_assert ((offsetof (struct d, e) < -1) == (INT_MAX < (size_t) -1));
      51  
      52  /* Check max_align_t's alignment.  */
      53  static_assert (alignof (double) <= alignof (max_align_t));
      54  static_assert (alignof (int) <= alignof (max_align_t));
      55  static_assert (alignof (long double) <= alignof (max_align_t));
      56  static_assert (alignof (long int) <= alignof (max_align_t));
      57  static_assert (alignof (ptrdiff_t) <= alignof (max_align_t));
      58  static_assert (alignof (size_t) <= alignof (max_align_t));
      59  static_assert (alignof (wchar_t) <= alignof (max_align_t));
      60  static_assert (alignof (struct d) <= alignof (max_align_t));
      61  #if defined __GNUC__ || defined __clang__ || defined __IBM__ALIGNOF__
      62  static_assert (__alignof__ (double) <= __alignof__ (max_align_t));
      63  static_assert (__alignof__ (int) <= __alignof__ (max_align_t));
      64  static_assert (__alignof__ (long double) <= __alignof__ (max_align_t));
      65  static_assert (__alignof__ (long int) <= __alignof__ (max_align_t));
      66  static_assert (__alignof__ (ptrdiff_t) <= __alignof__ (max_align_t));
      67  static_assert (__alignof__ (size_t) <= __alignof__ (max_align_t));
      68  static_assert (__alignof__ (wchar_t) <= __alignof__ (max_align_t));
      69  static_assert (__alignof__ (struct d) <= __alignof__ (max_align_t));
      70  #endif
      71  
      72  int
      73  main (void)
      74  {
      75    return 0;
      76  }