From owner-freebsd-toolchain@freebsd.org Fri May 26 00:29:14 2017 Return-Path: Delivered-To: freebsd-toolchain@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 0B8F4D7AFA0 for ; Fri, 26 May 2017 00:29:14 +0000 (UTC) (envelope-from markmi@dsl-only.net) Received: from asp.reflexion.net (outbound-mail-210-62.reflexion.net [208.70.210.62]) (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 AFBD9118C for ; Fri, 26 May 2017 00:29:13 +0000 (UTC) (envelope-from markmi@dsl-only.net) Received: (qmail 15302 invoked from network); 26 May 2017 00:29:11 -0000 Received: from unknown (HELO mail-cs-01.app.dca.reflexion.local) (10.81.19.1) by 0 (rfx-qmail) with SMTP; 26 May 2017 00:29:11 -0000 Received: by mail-cs-01.app.dca.reflexion.local (Reflexion email security v8.40.0) with SMTP; Thu, 25 May 2017 20:29:12 -0400 (EDT) Received: (qmail 6258 invoked from network); 26 May 2017 00:29:11 -0000 Received: from unknown (HELO iron2.pdx.net) (69.64.224.71) by 0 (rfx-qmail) with (AES256-SHA encrypted) SMTP; 26 May 2017 00:29:11 -0000 Received: from [192.168.1.114] (c-76-115-7-162.hsd1.or.comcast.net [76.115.7.162]) by iron2.pdx.net (Postfix) with ESMTPSA id 1A3FAEC7D4D; Thu, 25 May 2017 17:29:11 -0700 (PDT) Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 10.3 \(3273\)) Subject: Re: llvm FreeBSD powerpc ABI target bug fix: Re: [Bug 26519] Clang 4.0.0's "Target: powerpc-unknown-freebsd11.0" code generation is violating the SVR4 ABI (SEGV can result) From: Mark Millard In-Reply-To: <45696549-B3B7-4080-AB2B-7A1DC0966C81@FreeBSD.org> Date: Thu, 25 May 2017 17:29:10 -0700 Cc: FreeBSD Toolchain , FreeBSD PowerPC ML Content-Transfer-Encoding: 7bit Message-Id: References: <0103401A-CEEA-4992-A45E-E60EA151119B@dsl-only.net> <893ECA11-7C80-4D24-A496-92ADC7978A07@FreeBSD.org> <408D3509-3D62-4413-986B-6C1171FB6138@dsl-only.net> <45696549-B3B7-4080-AB2B-7A1DC0966C81@FreeBSD.org> To: Dimitry Andric X-Mailer: Apple Mail (2.3273) X-BeenThere: freebsd-toolchain@freebsd.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Maintenance of FreeBSD's integrated toolchain List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 26 May 2017 00:29:14 -0000 On 2017-May-25, at 4:31 PM, Dimitry Andric wrote: > On 25 May 2017, at 23:59, Mark Millard wrote: >> >> Is llvm bugzilla's latest 26519 fix going to make it >> into release/11.1.0 ? This fixes the last known stack >> handling ABI violation for targeting powerpc FreeBSD >> (32-bit). > > I just committed it in r318906. It should make 11.1-RELEASE. Would be > nice if we can finally close PR 206990. :) To my knowledge there are no more stack handling problems and use of the update should provide evidence that 206990 can be closed. But it may be a while before I update to direct use of something after head -r317820. . . I've frozen at head -317820 while trying to get evidence for a periodic powerpc kernel panic in that version (kernel built with gcc 4.2.1, worlds via both compilers). Small adjustments that change the kernel memory layout a little tend to change the behavior, usually meaning no obvious symptoms. So updating to some other version likely just hides the problem. Unfortunately it frequently takes hours for the panic to occur and so a long time to conclude the panic is not likely to happen in any test that I have running. It may be that I just will not identify anything that points at anything fairly specific to fix but I've not given up yet. What I know of for powerpc's clang status with the stack handling fixes in place is: A) Handling thrown C++ exceptions crashes for code generated by clang. (powerpc64 also has this property.) B) A clang-based kernel fails to start /sbin/init and then gets a data alignment panic. Past investigations relative to (A) suggest multiple problems are around that contribute, it is not just one simple problem. I've not looked at (B) yet. === Mark Millard markmi at dsl-only.net