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Re: [PATCH/gfortran] Fix rounding in constant folding


On Sat, Apr 09, 2005 at 09:13:52PM +0200, Tobias Schl?ter wrote:
> Tobias Schl?ter wrote:
> > Steve Kargl wrote:
> > 
> >>>In order of increasing probability: Does mpfr round incorrectly? Do we do
> >>>something wrong?  Or am I being stupid?
> > 
> > 
> > Further investigation proved the last of these options to be the case.
> 
> Hm, upon looking at this again, this is not the case, and therefore is the
> case again.  The important conclusion is that our implementation of NEAREST is
> wrong:

I suspect we'll need to revisit all of these types of 
intrinsics (ie., nearest, rrspacing, ceiling, etc).
When I changed gfortran from mpf to mpfr, I did not
consider the robustness of the algorithms.  I did
a straight forward translation.

-- 
Steve


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