From: Andoni Arregi <andoni.arregui@gtd-gmbh.de>
To: Paul Zimmermann <Paul.Zimmermann@inria.fr>, newlib@sourceware.org
Subject: Re: regression in Newlib 4.2.0 (lgammaf)
Date: Wed, 09 Feb 2022 17:49:55 +0100 [thread overview]
Message-ID: <f53e6bcd894c9760210625eb9084c02ac04fbb9a.camel@gtd-gmbh.de> (raw)
In-Reply-To: <mw35kxbyxz.fsf@tomate.loria.fr>
Dear Paul,
here again, although we can provide a fix, we cannot understand well
enough why this didn't seem to be present in Newlib 4.1.0. The source
code regarding the incorrect limit at |x|<2**-70 has been there since
decades.
Best regards
On Sat, 2022-02-05 at 07:38 +0100, Paul Zimmermann wrote:
> Hi,
>
> a third regression in Newlib 4.2.0 for single precision:
>
> Checking lgamma with newlib-4.2.0.20211231
> MPFR library: 4.1.0
> MPFR header: 4.1.0 (based on 4.1.0)
> Checking function mylgammaf with MPFR_RNDN
> libm wrong by up to 8.93e+43 ulp(s) for x=-0x1p-70
> mylgamma gives inf
> mpfr_mylgamma gives 0x1.842994p+5
>
> The largest error for lgammaf in Newlib 4.1.0 was 7.50e6 ulps
> (for x=-0x1.3a7fcap+1).
>
> Paul
--
Andoni Arregi
Geschäftsführer
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http://www.gtd-gmbh.de andoni.arregi@gtd-gmbh.de
next prev parent reply other threads:[~2022-02-09 16:52 UTC|newest]
Thread overview: 15+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-02-05 6:38 Paul Zimmermann
2022-02-09 16:28 ` [PATCH 1/2] Improve lgammaf range for very small cases Andoni Arregi
2022-02-10 14:58 ` Corinna Vinschen
2022-02-10 16:07 ` [PATCH 0/2] Fix lgammaf and lgamma for small ranges and in [2, 3[ Andoni Arregi
2022-02-10 16:10 ` [PATCH 1/2] Improve lgammaf range for very small cases Andoni Arregi
2022-02-10 16:21 ` Paul Zimmermann
2022-02-10 16:12 ` [PATCH 2/2] Add a missing default case in lgamma Andoni Arregi
2022-02-10 17:29 ` Paul Zimmermann
2022-02-11 11:14 ` Andoni Arregi
2022-02-10 16:16 ` [PATCH 1/2] Improve lgammaf range for very small cases Andoni Arregi
2022-02-11 11:19 ` Andoni Arregi
2022-02-09 16:30 ` [PATCH 2/2] Add a missing default case in lgamma Andoni Arregi
2022-02-09 16:49 ` Andoni Arregi [this message]
2022-02-11 11:16 ` [PATCH] Improve lgammaf range for very small cases Andoni Arregi
2022-02-14 13:46 ` Corinna Vinschen
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