Files
calc/have_unused.c
2017-05-21 15:38:57 -07:00

90 lines
2.2 KiB
C

/*
* have_unused - Determine if we want or can support the unused attribute
*
* Copyright (C) 2004 Landon Curt Noll
*
* Calc is open software; you can redistribute it and/or modify it under
* the terms of the version 2.1 of the GNU Lesser General Public License
* as published by the Free Software Foundation.
*
* Calc is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General
* Public License for more details.
*
* A copy of version 2.1 of the GNU Lesser General Public License is
* distributed with calc under the filename COPYING-LGPL. You should have
* received a copy with calc; if not, write to Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
* @(#) $Revision: 30.1 $
* @(#) $Id: have_unused.c,v 30.1 2007/03/16 11:09:46 chongo Exp $
* @(#) $Source: /usr/local/src/bin/calc/RCS/have_unused.c,v $
*
* Under source code control: 2004/02/22 22:36:10
* File existed as early as: 2004
*
* chongo <was here> /\oo/\ http://www.isthe.com/chongo/
* Share and enjoy! :-) http://www.isthe.com/chongo/tech/comp/calc/
*/
/*
* usage:
* have_unused
*
* Not all compilers support the unused attribute, so this may not compile
* on your system.
*
* This prog outputs several defines:
*
* HAVE_UNUSED
* defined ==> ok to use unused
* undefined ==> do not use unused
*
* UNUSED
* unused ==> use unused
* (nothing) ==> unused not used
*/
#include <stdio.h>
#if !defined(HAVE_NO_UNUSED)
/* make sure that we can use the __attribute__((unused)) in #define's */
#undef UNUSED
#define UNUSED __attribute__((unused))
/*
* unused_str - a function with an unused argument
*/
static char *
unused_str(char UNUSED *str)
{
return "__attribute__((unused))";
}
#endif /* !HAVE_NO_UNUSED */
int
main(void)
{
#if defined(HAVE_NO_UNUSED)
printf("#undef HAVE_UNUSED /* no */\n");
printf("#undef UNUSED\n");
printf("#define UNUSED /* no */\n");
#else /* HAVE_NO_UNUSED */
printf("#define HAVE_UNUSED /* yes */\n");
printf("#undef UNUSED\n");
printf("#define UNUSED %s /* yes */\n", unused_str(NULL));
#endif /* HAVE_NO_UNUSED */
/* exit(0); */
return 0;
}