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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_DEFUN([gt_BITFIELD_TYPE_MATTERS],
[
AC_CACHE_CHECK([if the type of bitfields matters], gt_cv_bitfield_type_matters,
[
AC_TRY_COMPILE(
[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
AC_DEFINE(HAVE_BITFIELD_TYPE_MATTERS, 1,
[Define if the type of bitfields effects alignment.])
fi
])
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