Date: Thu, 12 Jun 2003 14:14:19 +1000 From: Tim Robbins <tjr@FreeBSD.ORG> To: Kris Kennaway <kris@obsecurity.org> Cc: current@freebsd.org Subject: Re: CSTD=c99 breaks package creation Message-ID: <20030612141419.A54664@dilbert.robbins.dropbear.id.au> In-Reply-To: <20030612023701.GA33532@rot13.obsecurity.org>; from kris@obsecurity.org on Wed, Jun 11, 2003 at 07:37:01PM -0700 References: <20030610113858.GA99227@rot13.obsecurity.org> <20030612023701.GA33532@rot13.obsecurity.org>
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--9jxsPFA5p3P2qPhR Content-Type: text/plain; charset=us-ascii Content-Disposition: inline On Wed, Jun 11, 2003 at 07:37:01PM -0700, Kris Kennaway wrote: > It's possible that there's either a bug in gcc or there is C code in > the system that has a different meaning when interpreted to C99 > standards. I think I may have found the problem, and I think it's in GNU tar. GNU tar does this: #ifndef __attribute__ /* This feature is available in gcc versions 2.5 and later. */ # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5) || __STRICT_ANSI__ # define __attribute__(Spec) /* empty */ # endif #endif machine/_types.h does this: typedef int __attribute__((__mode__(__DI__))) __int64_t; typedef unsigned int __attribute__((__mode__(__DI__))) __uint64_t; If __attribute__ is empty, __int64_t becomes a synonym for int. Bad. Attached is a test program. Compile it w/o a -std option and see that the output, which is sizeof(int64_t), is 8 as expected. Compile with -std=c99 and see that sizeof(int64_t) is 4. Tim --9jxsPFA5p3P2qPhR Content-Type: text/plain; charset=us-ascii Content-Disposition: attachment; filename="test.c" #ifndef __attribute__ /* This feature is available in gcc versions 2.5 and later. */ # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 5) || __STRICT_ANSI__ # define __attribute__(Spec) /* empty */ # endif #endif #include <sys/types.h> #include <stdio.h> #include <stdint.h> #include <stdlib.h> int main(int argc, char *argv[]) { (void)__bswap64((uint64_t)3); printf("%d\n", (int)sizeof(uint64_t)); exit(0); } --9jxsPFA5p3P2qPhR--
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