From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gtd-gmbh.de (mail.gtd.eu [46.24.46.35]) by sourceware.org (Postfix) with ESMTPS id 1FA5E3858D28 for ; Wed, 9 Feb 2022 16:52:06 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org 1FA5E3858D28 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=gtd-gmbh.de Authentication-Results: sourceware.org; spf=none smtp.mailfrom=gtd-gmbh.de X-MDAV-Result: clean X-MDAV-Processed: gtd-gmbh.de, Wed, 09 Feb 2022 17:50:01 +0100 Received: by gtd-gmbh.de (MDaemon PRO v21.0.3) with ESMTPSA id md5001016213283.msg; Wed, 09 Feb 2022 17:50:00 +0100 X-Spam-Processed: gtd-gmbh.de, Wed, 09 Feb 2022 17:50:00 +0100 (not processed: message from trusted or authenticated source) X-MDRemoteIP: 109.90.104.197 X-MDArrival-Date: Wed, 09 Feb 2022 17:50:00 +0100 X-Authenticated-Sender: andoni.arregui@gtd-gmbh.de X-Return-Path: prvs=1039b972d0=andoni.arregui@gtd-gmbh.de X-Envelope-From: andoni.arregui@gtd-gmbh.de X-MDaemon-Deliver-To: newlib@sourceware.org Message-ID: Subject: Re: regression in Newlib 4.2.0 (lgammaf) From: Andoni Arregi Reply-To: andoni.arregui@gtd-gmbh.de To: Paul Zimmermann , newlib@sourceware.org Date: Wed, 09 Feb 2022 17:49:55 +0100 In-Reply-To: References: Organization: GTD GmbH Content-Type: text/plain; charset="UTF-8" User-Agent: Evolution 3.42.3 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-MDCFSigsAdded: gtd-gmbh.de X-Spam-Status: No, score=-2.9 required=5.0 tests=BAYES_00, BODY_8BITS, KAM_DMARC_STATUS, KAM_LAZY_DOMAIN_SECURITY, SPF_HELO_NONE, SPF_NONE, TXREP, T_SCC_BODY_TEXT_LINE autolearn=no autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: newlib@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Newlib mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 09 Feb 2022 16:52:08 -0000 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 GTD GmbH Ravensburger Str. 32a, 88677 Markdorf T: +49 7544 96440 22 | M: +49 151 65620499 | F: +49 7544 96440 29 http://www.gtd-gmbh.de andoni.arregi@gtd-gmbh.de