From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on dcvr.yhbt.net X-Spam-Level: X-Spam-ASN: AS4713 221.184.0.0/13 X-Spam-Status: No, score=-2.5 required=3.0 tests=AWL,BAYES_00, DKIM_ADSP_CUSTOM_MED,FORGED_GMAIL_RCVD,FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED,SPF_HELO_NONE,SPF_PASS,UNPARSEABLE_RELAY shortcircuit=no autolearn=no autolearn_force=no version=3.4.2 Received: from neon.ruby-lang.org (neon.ruby-lang.org [221.186.184.75]) by dcvr.yhbt.net (Postfix) with ESMTP id 45D331F4B4 for ; Thu, 15 Apr 2021 01:34:29 +0000 (UTC) Received: from neon.ruby-lang.org (localhost [IPv6:::1]) by neon.ruby-lang.org (Postfix) with ESMTP id 0AC3C120C94; Thu, 15 Apr 2021 10:33:27 +0900 (JST) Received: from xtrwkhkc.outbound-mail.sendgrid.net (xtrwkhkc.outbound-mail.sendgrid.net [167.89.16.28]) by neon.ruby-lang.org (Postfix) with ESMTPS id D7AAD120B4C for ; Thu, 15 Apr 2021 10:33:24 +0900 (JST) Received: by filterdrecv-54f669f855-fzzfk with SMTP id filterdrecv-54f669f855-fzzfk-14-6077981F-14 2021-04-15 01:34:23.338791185 +0000 UTC m=+189573.834513561 Received: from herokuapp.com (unknown) by ismtpd0165p1mdw1.sendgrid.net (SG) with ESMTP id fN3pS7svRdqDIVfFS6-QiQ for ; Thu, 15 Apr 2021 01:34:23.147 +0000 (UTC) Date: Thu, 15 Apr 2021 01:34:23 +0000 (UTC) From: xtkoba+ruby@gmail.com Message-ID: References: Mime-Version: 1.0 X-Redmine-Project: ruby-master X-Redmine-Issue-Tracker: Bug X-Redmine-Issue-Id: 17804 X-Redmine-Issue-Author: chasonr X-Redmine-Sender: xtkoba X-Mailer: Redmine X-Redmine-Host: bugs.ruby-lang.org X-Redmine-Site: Ruby Issue Tracking System X-Auto-Response-Suppress: All Auto-Submitted: auto-generated X-Redmine-MailingListIntegration-Message-Ids: 79502 X-SG-EID: =?us-ascii?Q?75w3+RXRrinEP3ykAS=2F1WzD2vTMrJdTeEiaFbXc9IwUpa82uS+TZ3ob5EOcZS4?= =?us-ascii?Q?IOlK8mZCK+oNPu+Ntuv3m9Cef4fOC+aNyuk4lxI?= =?us-ascii?Q?xLH+5pTbpWIBS9V8=2FNOb8yCc6BlvS9lCm9BvPvh?= =?us-ascii?Q?N48mwA25dZ6VrGJlgdnf367bZJpm58IVyf6WxMx?= =?us-ascii?Q?9+ECm3zuC+3GBs7mcev9D=2F2Ji6NGVuo3LBg=3D=3D?= To: ruby-core@ruby-lang.org X-Entity-ID: b/2+PoftWZ6GuOu3b0IycA== X-ML-Name: ruby-core X-Mail-Count: 103456 Subject: [ruby-core:103456] [Ruby master Bug#17804] Math.cbrt(0.0) returns NaN X-BeenThere: ruby-core@ruby-lang.org X-Mailman-Version: 2.1.15 Precedence: list Reply-To: Ruby developers List-Id: Ruby developers List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: ruby-core-bounces@ruby-lang.org Sender: "ruby-core" Issue #17804 has been updated by xtkoba (Tee KOBAYASHI). FWIW, that code was introduced by commit commit:c995315153f7403636ec0d6119b7885668b32039. ---------------------------------------- Bug #17804: Math.cbrt(0.0) returns NaN https://bugs.ruby-lang.org/issues/17804#change-91551 * Author: chasonr (Ray Chason) * Status: Open * Priority: Normal * ruby -v: ruby 3.0.1p64 (2021-04-05 revision 0fb782ee38) [x86_64-linux] * Backport: 2.6: UNKNOWN, 2.7: UNKNOWN, 3.0: UNKNOWN ---------------------------------------- Math.cbrt(0.0) returns NaN. It should return 0.0. >From reading the implementation, I expect this bug to happen only if glibc is in use. The failing section reads: #if defined __GLIBC__ if (isfinite(r)) { r = (2.0 * r + (f / r / r)) / 3.0; } #endif and this produces a NaN when f and r are both 0. -- https://bugs.ruby-lang.org/