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Re: Fix exp in non-default rounding modes (bug 3976)
From: "Joseph S. Myers" <joseph@codesourcery.com>
Date: Wed, 29 Feb 2012 02:04:28 +0000 (UTC)
> On Tue, 28 Feb 2012, David Miller wrote:
>
>> From: "Joseph S. Myers" <joseph@codesourcery.com>
>> Date: Wed, 29 Feb 2012 01:51:31 +0000 (UTC)
>>
>> > No, it's not undefined;
>>
>> I'm just saying that this is the exact language I've seen in Sun's
>> documentation for libm, it's "undefined".
>
> I think C99 and C11 Annex F are what's relevant here, not Sun's libm
> documentation. The entire standard C library may be called in any
> rounding mode and must still meet the semantics given for each function.
Fair enough, perhaps someone can put in the effort to find algorithms
that don't give wildly inaccurate numbers in rounding modes other
than to-nearest.