view config/bitfields.m4 @ 158:494b0b89df80 default tip

author Shinji KONO <>
date Mon, 25 May 2020 18:13:55 +0900
parents 04ced10e8804
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dnl Copyright (C) 2015 Free Software Foundation, Inc.
dnl This file is free software, distributed under the terms of the GNU
dnl General Public License.  As a special exception to the GNU General
dnl Public License, this file may be distributed as part of a program
dnl that contains a configuration script generated by Autoconf, under
dnl the same distribution terms as the rest of that program.

# Define HAVE_BITFIELD_TYPE_MATTERS if the type of bitfields effects their
# alignment.

  AC_CACHE_CHECK([if the type of bitfields matters], gt_cv_bitfield_type_matters,
      [struct foo1 { char x; char y:1; char z; };
struct foo2 { char x; long long int y:1; char z; };
int foo1test[ sizeof (struct foo1) < sizeof (struct foo2) ? 1 : -1 ]; ],
      [], gt_cv_bitfield_type_matters=yes, gt_cv_bitfield_type_matters=no)
  if test $gt_cv_bitfield_type_matters = yes; then
      [Define if the type of bitfields effects alignment.])