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From: Martin Stromberg <Martin DOT Stromberg AT epl DOT ericsson DOT se>
Message-Id: <200303180858.JAA03661@lws256.lu.erisoft.se>
Subject: Re: isnan and isinf
To: djgpp-workers AT delorie DOT com
Date: Tue, 18 Mar 2003 09:58:34 +0100 (MET)
In-Reply-To: <7704-Tue18Mar2003082230+0200-eliz@elta.co.il> from "Eli Zaretskii" at Mar 18, 2003 08:22:30 AM
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Hello.

Eli said:
> > From: <ams AT ludd DOT luth DOT se>
> > Date: Mon, 17 Mar 2003 19:13:29 +0100 (CET)
> > 
> > Now that isnan() and isinf() and their friends are in C99, should the
> > code in libm be moved into libc?
> 
> IMHO, we should indeed have these functions in libc.a, but perhaps a
> simpler code could be written to implement them.  While at that, how
> about supporting IA32-specific bit patterns for Inf's and NaN's (see
> the Intel manual for details)?

Huh!? 

1. Are you saying isnan() doesn't detect all possible nans? The code
in src/libm/math/sf_isnan.c looks correct to me.

2. The code in src/libm/math/sf_isnan.c doesn't look overly
complex. In fact it looks like it will be hard to improve it.

3. I only know about one bit pattern for inf and another one for
-inf. Are there other ones?


Right,

						MartinS