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Date: Thu, 19 Mar 1998 09:56:06 +0100
From: Thomas Koehler <T DOT Koehler AT pfh DOT research DOT philips DOT com>
Organization: Philips
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To: Marc Lehmann <pcg AT goof DOT com>
CC: beastium-list AT desk DOT nl
Subject: Re: paranoia & extra precision [was -fno-float-store in pgcc]
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Marc Lehmann wrote:
> 
> On Fri, Mar 13, 1998 at 04:09:21PM +0100, Thomas Koehler wrote:
> 
> > so what is the difference between the behaviour of programs compiled
> > with -ffloat-store compared to setting the FPU-rounding mode to double
> > via __setfpucw? (except that the -ffloat-store variante is much slower).
> 
> you can still program ansi c.

I think you mean that I can program platform independent (which ansi c
rule is violated if I use __setfpucw in my programs?)

> 
> with setfpucw, you have to store the cw on almost every fpu operation.
> gcc already does this for integer concersions (for other reasons).

Interesting. If I set the fpucw on startup in main using __setfpucw
(e.g. because I want to get SIGFPE's), is it ensured that the rest of
the program is executed with this fpucw?

-- 



Thomas Koehler
Philips Research Laboratories
Division Technical Systems
Roentgenstrasse 24-26
D-22335 Hamburg
Germany

phone:  +40/5078-2103
e-mail: T DOT Koehler AT PFH DOT Research DOT Philips DOT com