Date: Tue, 25 Apr 2000 00:05:23 -0700 From: Brooks Davis <brooks@one-eyed-alien.net> To: Nate Lawson <nate@elite.net> Cc: freebsd-hackers@FreeBSD.ORG, freebsd-ports@FreeBSD.ORG, davidm@hpl.hp.com Subject: Re: floating point exceptions Message-ID: <20000425000523.A17224@orion.ac.hmc.edu> In-Reply-To: <Pine.BSD.3.91.1000424233753.13392A-100000@almond.elite.net>; from nate@elite.net on Mon, Apr 24, 2000 at 11:44:59PM -0700 References: <Pine.BSD.3.91.1000424233753.13392A-100000@almond.elite.net>
next in thread | previous in thread | raw e-mail | index | archive | help
On Mon, Apr 24, 2000 at 11:44:59PM -0700, Nate Lawson wrote:
> I am running FreeBSD 4.0-RELEASE on x86 with gcc 2.95.2 and the
> httperf-0.6 port gives a SIGFPE and dumps core when run against a system
> that has no web server running. (The default behavior is to measure
> localhost when no arguments are specified).
>
> It seems this is caused by a divide by zero error since the delta between
> connections ends up being zero. The author suggest that the divide
> should return a defined value, Inf, according to the IEEE floating point
> standard. FreeBSD generates SIGFPE. I temporarily patched the code
> locally to check for a delta of zero and arbitrarily set it to 1.0 so
> that the divide succeeds and everything comes out ok without crashing.
>
> Is FreeBSD's behavior correct? Why or why not? You can use the included
> code snippet to verify that this occurs.
FreeBSD has traditionaly violated the IEEE FP standard in this regard.
This is fixed in 5.0 and I think in 4.0-STABLE (though I can't remember
what file this is in so I can't check.) If upgrading to -stable isn't
an option you can add a call to fpsetmask(3) in the application as
follows (this will work on Solaris and Irix as well):
#include <ieeefp.h>
<...>
main() {
<declare things>
fpsetmask(0);
<...>
}
-- Brooks
--
Any statement of the form "X is the one, true Y" is FALSE.
To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-ports" in the body of the message
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20000425000523.A17224>