Skip site navigation (1)Skip section navigation (2)
Date:      Sat, 18 Dec 1999 16:42:37 +1100 (EST)
From:      Bruce Evans <bde@zeta.org.au>
To:        Pascal Hofstee <daeron@Wit401305.student.utwente.nl>
Cc:        freebsd-current@FreeBSD.ORG
Subject:   Re: minor gcc-issue ?
Message-ID:  <Pine.BSF.4.10.9912181625070.3027-100000@alphplex.bde.org>
In-Reply-To: <Pine.BSF.4.21.9912171646310.39670-100000@shadowmere.student.utwente.nl>

next in thread | previous in thread | raw e-mail | index | archive | help
On Fri, 17 Dec 1999, Pascal Hofstee wrote:

> On Sat, 18 Dec 1999, Bruce Evans wrote:
> 
> > 0301 is an old (bad) way of spelling
> > MASK_80387 | MASK_IEEE_FP | MASK_FLOAT_RETURNS.  Cygnus finally fixed it in
> > in gcc/config/i386/freebsd.h on 1999/03/23 (see the ChangeLog), but FreeBSD
> > hasn't merged the change.
> 
> Thanks ... I do have on eother question though ... does this mean that
> FreeBSD by default compiles with the -mieee-fp compile switch. As that is

Yes.

> the solution (for SIGFPE issues) suggested by some Mozilla people on
> Bugzilla.

Very unlikely.  -mieee-fp just fixes comparisons of Quiet NaNs with 0, at
a small cost in efficiency.  As a side effect, this prevents SIGFPEs for
comparisons of Quiet NaNs with 0 when the invalid-operand exception is
not masked, but if you have a Quiet NaN, then you are probably running
with invalid-operand exceptions masked and wouldn't be worried about
SIGFPEs.  Quiet NaNs are normally generated by invalid operations, e.g.,
0.0/0.0 when the invalid-operand exception is masked.  If this exception
is unmasked, then 0.0/0.0 generates a SIGFPE and leaves the operands on
the FPU stack.

Bruce



To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message




Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?Pine.BSF.4.10.9912181625070.3027-100000>