Date: Sat, 30 Aug 2003 23:12:25 +0100 From: David Taylor <davidt@yadt.co.uk> To: Garrett Wollman <wollman@khavrinen.lcs.mit.edu> Cc: freebsd-bugs@FreeBSD.org Subject: Re: misc/56206: src/sys/sys/cdefs.h uses PreProcessor variables that aren't defined, causing noisy warnings. Message-ID: <20030830221225.GB8404@gattaca.yadt.co.uk> In-Reply-To: <200308302030.h7UKU5xO055369@freefall.freebsd.org> References: <200308302030.h7UKU5xO055369@freefall.freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
On Sat, 30 Aug 2003, Garrett Wollman wrote: > The following reply was made to PR misc/56206; it has been noted by GNATS. > > From: Garrett Wollman <wollman@khavrinen.lcs.mit.edu> > To: Larry Rosenman <ler@lerctr.org> > Cc: FreeBSD-gnats-submit@freebsd.org > Subject: Re: misc/56206: src/sys/sys/cdefs.h uses PreProcessor variables > that aren't defined, causing noisy warnings. > Date: Sat, 30 Aug 2003 16:26:52 -0400 (EDT) > >>>> -#if __STDC_VERSION__ < 199901 >>>> +#if defined(__STDC_VERSION__) && __STDC_VERSION__ < 199901 >>> >>> 0 < 199901 >> and doesn't the #if __STDC_VERSION__ < 199901 have the same effect, except > > Let me try to spell this out. > > When __STDC_VERSION__ is not defined, the preprocessor expression > `__STDC_VERSION < 199901' evaluates, by definition, to true, because > 0L < 199901L (which is why I consider this GCC warning to be bogus). > > When __STDC_VERSION__ is not defined, the preprocessor expression > `defined(__STDC_VERSION__) && __STDC_VERSION__ < 199901' evaluates to > false, because __STDC_VERSION__ is not defined. > > -GAWollman Presumably the patch: -#if __STDC_VERSION__ < 199901 +#if !defined(__STDC_VERSION__) || (__STDC_VERSION__ < 199901) Would keep the original behaviour, and silence GCC's warning. Whether you you want to apply the patch or change GCC, however, isn't a decision I am remotely qualified to make... -- David Taylor davidt@yadt.co.uk "The future just ain't what it used to be"
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20030830221225.GB8404>