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Re: test release gsl-1.9.90.tar.gz


At Thu, 13 Sep 2007 10:30:14 -0600,
Patrick Alken wrote:
> I am wondering if maybe the version of gcc (3.2.3) is causing the
> problem. I tried make check again on another 64 bit machine with gcc
> 4.1.1 and everything went ok.

It's possible, but it doesn't necessarily indicate a problem with the
compiler itself.  It depends whether the value was computed with SSE
or X87 instructions.

The starting values of the recurrence were O(1e-310).  These would
underflow to zero in SSE arithmetic, which does not have denormalised
numbers, so the final result would be zero.  With X87 instructions,
there wouldn't be any underflow, and the final result comes out ok.

-- 
Brian Gough


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