From owner-freebsd-current@FreeBSD.ORG Thu May 22 12:08:22 2003 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 0E68637B401 for ; Thu, 22 May 2003 12:08:20 -0700 (PDT) Received: from HAL9000.homeunix.com (12-233-57-131.client.attbi.com [12.233.57.131]) by mx1.FreeBSD.org (Postfix) with ESMTP id 5748E43F85 for ; Thu, 22 May 2003 12:08:19 -0700 (PDT) (envelope-from das@FreeBSD.ORG) Received: from HAL9000.homeunix.com (localhost [127.0.0.1]) by HAL9000.homeunix.com (8.12.9/8.12.5) with ESMTP id h4MJ8HXD002422; Thu, 22 May 2003 12:08:17 -0700 (PDT) (envelope-from das@FreeBSD.ORG) Received: (from das@localhost) by HAL9000.homeunix.com (8.12.9/8.12.5/Submit) id h4MJ8Hij002421; Thu, 22 May 2003 12:08:17 -0700 (PDT) (envelope-from das@FreeBSD.ORG) Date: Thu, 22 May 2003 12:08:17 -0700 From: David Schultz To: Anti Message-ID: <20030522190817.GB2295@HAL9000.homeunix.com> Mail-Followup-To: Anti , freebsd-current@freebsd.org References: <200305201025.30296.jlido@goof.com> <200305201512.27174.jlido@goof.com> <20030522011014.GC27806@dragon.nuxi.com> <200305221010.59718.jlido@goof.com> <20030522093623.30915ed0.fearow@attbi.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20030522093623.30915ed0.fearow@attbi.com> cc: freebsd-current@FreeBSD.ORG Subject: Re: gcc/libm floating-point bug? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 22 May 2003 19:08:22 -0000 On Thu, May 22, 2003, Anti wrote: > > > > I feel some will screem if we take away the ability to use > > > -march=pentium4 in places they know for sure will work. Unix is about > > > mechanisms, not policy. > > > > Well, we've got a compiler here with a broken mechanism. Deciding whether or > > not to act on it sounds like a policy decision to me. I just hope 5.1 > > doesn't get shipped with such an easy way to break stuff. > > > p4 should expand to "-march=pentium4 -mno-sse2" (could set it to pentium3, but > then people would see pentium3 being used when they specified p4 and think it's > a bug)... > > any educated person with a legit reason to use -march=pentium4 without disabling > sse2 can always add it to CFLAGS instead of setting it in CPUTYPE... > > don't see why anyone wouldn't want to put an end to all the breakage and bug > reports due to this when the fix is so simple and of no real harm... When I last checked, -march=pentium4 was slower than -march=pentium3, and -msse2 was pretty much a wash in terms of performance, even though SSE2 shaved a few bytes off of FP code size. This implies that downgrading to -march=pentium3 is the better option, unless our goal is to dupe people who don't know well enough to read the documentation.