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Date: Fri, 5 Aug 2005 10:01:57 -0700
From: Steve Kargl <sgk@troutmask.apl.washington.edu>
To: Denis Antrushin <DAntrushin@mail.ru>
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Cc: freebsd-hackers@freebsd.org
Subject: Re: Number of significand bits in long double?
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On Fri, Aug 05, 2005 at 08:37:44PM +0400, Denis Antrushin wrote:
> Steve Kargl wrote:
> >On Fri, Aug 05, 2005 at 05:15:33PM +0400, Denis Antrushin wrote:
> >
> >>Steve Kargl wrote:
> >>
> >>>Can someone confirm or refute that the working number
> >>>of bits in the significand of long double type is 53
> >>>on i386?
> >>>
> >>
> >>Yes, this is what IEEE 754 requires.
> >>(See http://docs.sun.com/source/806-3568/ncg_goldberg.html,
> >>section 'The IEEE Standard')
> >>
> >
> >BZZZT.
> >
> >You're not even close to correct.  See Table 1 in the IEEE
> >754 standard and then read section 3.4.
> >
> 
> Well, you know the answer then ;-)

I know what IEEE-754 specifies.  I don't know what FreeBSD
implements.  In particular, float.h misrepresents long double
on i386.

-- 
Steve