| 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_COMPILE_IFELSE( | |
| [AC_LANG_PROGRAM([[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 | |
| ]) |