From owner-cvs-all Sat Mar 11 0:42:40 2000 Delivered-To: cvs-all@freebsd.org Received: from finch-post-10.mail.demon.net (finch-post-10.mail.demon.net [194.217.242.38]) by hub.freebsd.org (Postfix) with ESMTP id 496CA37B785; Sat, 11 Mar 2000 00:42:25 -0800 (PST) (envelope-from dfr@nlsystems.com) Received: from nlsys.demon.co.uk ([158.152.125.33] helo=herring.nlsystems.com) by finch-post-10.mail.demon.net with esmtp (Exim 2.12 #1) id 12ThTR-000KQ2-0A; Sat, 11 Mar 2000 08:42:13 +0000 Received: from salmon.nlsystems.com (salmon.nlsystems.com [10.0.0.3]) by herring.nlsystems.com (8.9.3/8.8.8) with ESMTP id IAA48871; Sat, 11 Mar 2000 08:48:52 GMT (envelope-from dfr@nlsystems.com) Date: Sat, 11 Mar 2000 08:44:34 +0000 (GMT) From: Doug Rabson To: Martin Cracauer Cc: Alfred Perlstein , Garrett Wollman , Martin Cracauer , cvs-committers@FreeBSD.ORG, cvs-all@FreeBSD.ORG Subject: Re: cvs commit: src/sys/i386/include npx.h In-Reply-To: <20000310224726.B20522@cons.org> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-cvs-all@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Fri, 10 Mar 2000, Martin Cracauer wrote: > In <20000310140843.C14279@fw.wintelcom.net>, Alfred Perlstein wrote: > > * Garrett Wollman [000310 13:58] wrote: > > > < said: > > > > > > > Is there any reason for doing this other than so we can emulate > > > > linux's bog^H^H^H nifty ability to divide by zero? > > > > > > The fact that the IEEE standard says this is the default state. > > > > I haven't had the time to test this, but integer divide by zero is > > still trapped? And you're right, using fp on solaris/irix doesn't > > bomb out when doing / 0, but does for integer math. > > Integer math is not affected by the FPU mask (Although the exceptions > thown is SIGFPE). You can't mask it, the only thing you can do is to > longjump out of a SIGFPE signal handler. > > Yes, out of the major Unix derivates we were the last to default to > trap (Solaris, Linux, NetBSD, OpenBSD...). Again, you can't clearly > claime that IEEE754 is the holy thing since we violate it otherwise > due to C89 restrictions. Also, the alpha port of FreeBSD has had this behaviour for a very long time for compatibility with OSF1. -- Doug Rabson Mail: dfr@nlsystems.com Nonlinear Systems Ltd. Phone: +44 181 442 9037 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe cvs-all" in the body of the message