From owner-freebsd-bugs@freebsd.org Sun Sep 24 11:31:19 2017 Return-Path: Delivered-To: freebsd-bugs@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id C6F5EE25E71 for ; Sun, 24 Sep 2017 11:31:19 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from kenobi.freebsd.org (kenobi.freebsd.org [IPv6:2001:1900:2254:206a::16:76]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id B000972867 for ; Sun, 24 Sep 2017 11:31:19 +0000 (UTC) (envelope-from bugzilla-noreply@freebsd.org) Received: from bugs.freebsd.org ([127.0.1.118]) by kenobi.freebsd.org (8.15.2/8.15.2) with ESMTP id v8OBVJUf026969 for ; Sun, 24 Sep 2017 11:31:19 GMT (envelope-from bugzilla-noreply@freebsd.org) From: bugzilla-noreply@freebsd.org To: freebsd-bugs@FreeBSD.org Subject: [Bug 222551] Code generated by Clang using union aliasing results in segmentation fault Date: Sun, 24 Sep 2017 11:31:19 +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: 11.1-RELEASE X-Bugzilla-Keywords: X-Bugzilla-Severity: Affects Many People X-Bugzilla-Who: 1983-01-06@gmx.net X-Bugzilla-Status: New X-Bugzilla-Resolution: X-Bugzilla-Priority: --- X-Bugzilla-Assigned-To: freebsd-bugs@FreeBSD.org 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: quoted-printable 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: 2.1.23 Precedence: list List-Id: Bug reports List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 24 Sep 2017 11:31:19 -0000 https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=3D222551 Bug ID: 222551 Summary: Code generated by Clang using union aliasing results in segmentation fault Product: Base System Version: 11.1-RELEASE Hardware: i386 OS: Any Status: New Severity: Affects Many People Priority: --- Component: bin Assignee: freebsd-bugs@FreeBSD.org Reporter: 1983-01-06@gmx.net This was discovered while working on https://svnweb.freebsd.org/ports/head/lang/duktape/. Using a double and an int array with eight elements corrupts the union. The issue has been reported against duktape: https://github.com/svaarala/duktape/issues/1752 , though already known since 2103 (http://lists.llvm.org/pipermail/cfe-users/2013-December/000321.html) = and it turned out to be a Clang bug in FreeBSD which has been fixed in 5.0.0: https://bugs.llvm.org/show_bug.cgi?id=3D32056. I simple example is availabe at https://github.com/svaarala/duktape/blob/master/misc/clang_aliasing.c. The fix from Clang trunk requires a backport to 4.0.x and update in FreeBSD base. Unfortunately, there is no workaround to this issue unless you install llvm50 from ports. --=20 You are receiving this mail because: You are the assignee for the bug.=