From owner-freebsd-bugs@FreeBSD.ORG Mon Jul 7 19:12:21 2014 Return-Path: Delivered-To: freebsd-bugs@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 84B081D0 for ; Mon, 7 Jul 2014 19:12:21 +0000 (UTC) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 5314C26D6 for ; Mon, 7 Jul 2014 19:12:21 +0000 (UTC) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.14.8/8.14.8) with ESMTP id s67JCLe1081152 for ; Mon, 7 Jul 2014 20:12:21 +0100 (BST) (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 191719] New: bin/expr doesn't detect some overflow errors with multiplication Date: Mon, 07 Jul 2014 19:12:21 +0000 X-Bugzilla-Reason: AssignedTo X-Bugzilla-Type: new X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: Base System X-Bugzilla-Component: bin X-Bugzilla-Version: 11.0-CURRENT X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Some People X-Bugzilla-Who: yaneurabeya@gmail.com X-Bugzilla-Status: Needs Triage X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: bug_id short_desc product version rep_platform op_sys bug_status bug_severity priority component assigned_to reporter Message-ID: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-Bugzilla-URL: https://bugs.freebsd.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 X-BeenThere: freebsd-bugs@freebsd.org X-Mailman-Version: 2.1.18 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 07 Jul 2014 19:12:21 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=191719 Bug ID: 191719 Summary: bin/expr doesn't detect some overflow errors with multiplication Product: Base System Version: 11.0-CURRENT Hardware: Any OS: Any Status: Needs Triage Severity: Affects Some People Priority: --- Component: bin Assignee: freebsd-bugs@FreeBSD.org Reporter: yaneurabeya@gmail.com If I do the following case, it doesn't fail on FreeBSD like it does NetBSD: % expr -- -4611686018427387904 \* 3 4611686018427387904 # python2 -c 'print -4611686018427387904 * 3' -13835058055282163712 This is could be fixed by adding a signage check to assert_times, like what's in assert_plus: if the signage of two numbers is not the same, i.e. one is negative, the other is positive -- then the value must be negative. 395 void 396 assert_plus(intmax_t a, intmax_t b, intmax_t r) 397 { 398 /* 399 * sum of two positive numbers must be positive, 400 * sum of two negative numbers must be negative 401 */ 402 if ((a > 0 && b > 0 && r <= 0) || 403 (a < 0 && b < 0 && r >= 0)) 404 errx(ERR_EXIT, "overflow"); 405 } ... 447 void 448 assert_times(intmax_t a, intmax_t b, intmax_t r) 449 { 450 /* 451 * if first operand is 0, no overflow is possible, 452 * else result of division test must match second operand 453 */ 454 if (a != 0 && r / a != b) 455 errx(ERR_EXIT, "overflow"); 456 } -- You are receiving this mail because: You are the assignee for the bug.