From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 32043 invoked by alias); 31 May 2005 12:17:13 -0000 Mailing-List: contact gcc-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Archive: List-Post: List-Help: Sender: gcc-owner@gcc.gnu.org Received: (qmail 31933 invoked by uid 22791); 31 May 2005 12:17:04 -0000 Received: from vinc17.net4.nerim.net (HELO ay.vinc17.org) (62.212.121.106) by sourceware.org (qpsmtpd/0.30-dev) with ESMTP; Tue, 31 May 2005 12:17:04 +0000 Received: from lefevre by ay.vinc17.org with local (Exim 4.50) id 1Dd5g5-0006F3-7x; Tue, 31 May 2005 14:17:01 +0200 Date: Tue, 31 May 2005 12:51:00 -0000 From: Vincent Lefevre To: gcc@gcc.gnu.org Subject: Re: What is wrong with Bugzilla? [Was: Re: GCC and Floating-Point] Message-ID: <20050531121701.GQ3541@ay.vinc17.org> Mail-Followup-To: gcc@gcc.gnu.org References: <002d01c5643c$cfcc1140$bebc2997@bagio> <26669933.1117479096256.JavaMail.root@dtm1eusosrv72.dtm.ops.eu.uu.net> <429B7506.8010107@moene.indiv.nluug.nl> Mime-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <429B7506.8010107@moene.indiv.nluug.nl> X-Mailer-Info: http://www.vinc17.org/mutt/ User-Agent: Mutt/1.5.9-vl-20050401i X-SW-Source: 2005-05/txt/msg01678.txt.bz2 On 2005-05-30 22:18:14 +0200, Toon Moene wrote: > Vincent Lefevre wrote: [...] > >First there is a bug in GCC concerning casts and assignments > >(see ISO/IEC 9899: 5.1.2.3#13, 6.3.1.5#2 and 6.3.1.8#2). > > > >But even this were fixed, many users would still complain. > >That's why I think that the Linux kernel should set the CPU > >in double-precision mode, like some other OS's (MS Windows, > >*BSD) -- but this is off-topic here. > > It's not off-topic. In fact, Jim Wilson argued this point here: > > http://gcc.gnu.org/ml/gcc/2003-08/msg01282.html > > "The best pragmatic solution is probably to set the rounding control > to 64-bits, [double precision -- 64-bits isn't correct since it's the sign + 53-bit mantissa + extended exponent range internally] Will gcc do that? This isn't up to the user himself to do that. > but then we lose access to long double which some people need, > and we still have excess precision problems for float." But as I said on my page, this isn't much a problem since users who really need *extended* precision can still set the rounding precision to extended precision; this isn't portable, but extended precision isn't portable anyway. -- Vincent Lefèvre - Web: 100% accessible validated (X)HTML - Blog: Work: CR INRIA - computer arithmetic / SPACES project at LORIA