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Mail Archives: cygwin/2007/04/19/13:54:47

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Date: Thu, 19 Apr 2007 10:54:28 -0700 (PDT)
From: "Cary R." <cygcary AT yahoo DOT com>
Subject: Re: newlib: pow function can produce incorrect results.
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Hmmm, something weird is going on at my end. I just
wrote a standalone C program to test just these cases
and some of them now work as expected! I do agree that
-1.0 to either +-infinity should be a nan, but then
using that same logic why is -1.1 to infinity and 0.9
to minus infinity equal to infinity and not nan?
Personally I don't really care which way it's done. I
just would like things to be consistent.

One of the newlib pow implementations has some
comments about how the special cases are handled, but
the comments don't match the behavior I'm getting with
either of my  programs. I guess I need to track down
exactly which pow is being called by each program.
Based on what things look like now I'm betting some
one redefined pow in the original program, grrr.

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