From mboxrd@z Thu Jan  1 00:00:00 1970
From: Michael Snyder <msnyder@cygnus.com>
To: Eli Zaretskii <eliz@is.elta.co.il>
Cc: Jim Blandy <jimb@cygnus.com>, gdb-patches@sources.redhat.com
Subject: Re: RFA: don't try to compare IEEE NaN's
Date: Thu, 07 Jun 2001 10:38:00 -0000
Message-id: <3B1FBC02.2865152D@cygnus.com>
References: <Pine.SUN.3.91.1010607091954.28343B-100000@is>
X-SW-Source: 2001-06/msg00137.html

Eli Zaretskii wrote:
> 
> On 6 Jun 2001, Jim Blandy wrote:
> 
> > What you're saying is that, between this:
> >
> >         union {
> >           float f;
> >           char bytes[80];
> >         } u;
> >
> >         for (i = 0; i < 80; i++)
> >           u.bytes[i] = something interesting;
> >
> > and this:
> >
> >         u.f = 2.7182818284590452354;
> >
> > that you're more concerned that the latter will put a NaN in u.f than
> > the former.
> 
> Yes.
> 
> > When, in fact, the exact problem I'm trying to fix is
> > that someone's first shot at the former strategy produced a NaN.
> 
> That's because the bit pattern used by the original code was a bit
> pattern of a NaN in the first place.  In other words, we've got
> exactly what we were asking for.  You cannot expect that with a
> literal FP constant like the one you used.

I was not specifically trying to create a NaN -- 
just a recognizeable bit pattern.

Michael