From owner-freebsd-standards@FreeBSD.ORG Tue Oct 2 17:59:55 2007 Return-Path: Delivered-To: freebsd-standards@FreeBSD.ORG Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id F050B16A418 for ; Tue, 2 Oct 2007 17:59:55 +0000 (UTC) (envelope-from das@FreeBSD.ORG) Received: from VARK.MIT.EDU (VARK.MIT.EDU [18.95.3.179]) by mx1.freebsd.org (Postfix) with ESMTP id 9546413C45A for ; Tue, 2 Oct 2007 17:59:55 +0000 (UTC) (envelope-from das@FreeBSD.ORG) Received: from VARK.MIT.EDU (localhost [127.0.0.1]) by VARK.MIT.EDU (8.14.1/8.14.1) with ESMTP id l92HNIpL095269; Tue, 2 Oct 2007 13:23:18 -0400 (EDT) (envelope-from das@FreeBSD.ORG) Received: (from das@localhost) by VARK.MIT.EDU (8.14.1/8.14.1/Submit) id l92HNIPq095268; Tue, 2 Oct 2007 13:23:18 -0400 (EDT) (envelope-from das@FreeBSD.ORG) Date: Tue, 2 Oct 2007 13:23:18 -0400 From: David Schultz To: Steve Kargl Message-ID: <20071002172317.GA95181@VARK.MIT.EDU> Mail-Followup-To: Steve Kargl , Bruce Evans , freebsd-standards@FreeBSD.ORG References: <20070928152227.GA39233@troutmask.apl.washington.edu> <20071001173736.U1985@besplex.bde.org> <20071002001154.GA3782@troutmask.apl.washington.edu> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20071002001154.GA3782@troutmask.apl.washington.edu> Cc: freebsd-standards@FreeBSD.ORG Subject: Re: long double broken on i386? X-BeenThere: freebsd-standards@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list List-Id: Standards compliance List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Tue, 02 Oct 2007 17:59:56 -0000 Just a quick note... Although it would be nice to get all this stuff right the first time, very few people are going to care if our trig functions are accurate to within 1 ulp for huge inputs; many competing math libraries don't guarantee that anyway. A programmer who asks for sinl(1000000000*PI + 0.01) is going to be disappointed regardless, because you can't represent the input accurately using IEEE-754 floating point. Most people just care about taking a program that uses sinl() and getting it to compile and run on FreeBSD, and most of those programs don't call sinl() with huge arguments. Anyway, my point is that if you have something that works reasonably well and doesn't have egregious errors, my suggestion is to just commit it and not kill yourself over whether the argument reduction is correct in the last ulp.