From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 75F00C64E69 for ; Tue, 24 Nov 2020 02:49:16 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 23CD020720 for ; Tue, 24 Nov 2020 02:49:15 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 23CD020720 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=telegraphics.com.au Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.35343.66822 (Exim 4.92) (envelope-from ) id 1khONl-0004Li-2m; Tue, 24 Nov 2020 02:48:41 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 35343.66822; Tue, 24 Nov 2020 02:48:41 +0000 X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1khONk-0004Lb-Uu; Tue, 24 Nov 2020 02:48:40 +0000 Received: by outflank-mailman (input) for mailman id 35343; Tue, 24 Nov 2020 02:48:39 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1khONj-0004LW-LG for xen-devel@lists.xenproject.org; Tue, 24 Nov 2020 02:48:39 +0000 Received: from kvm5.telegraphics.com.au (unknown [98.124.60.144]) by us1-rack-iad1.inumbo.com (Halon) with ESMTP id 0ff3c3fd-67c8-4c3f-94a2-bc2cd37df513; Tue, 24 Nov 2020 02:48:38 +0000 (UTC) Received: from localhost (localhost.localdomain [127.0.0.1]) by kvm5.telegraphics.com.au (Postfix) with ESMTP id EF15F2AA0D; Mon, 23 Nov 2020 21:48:35 -0500 (EST) Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1khONj-0004LW-LG for xen-devel@lists.xenproject.org; Tue, 24 Nov 2020 02:48:39 +0000 X-Inumbo-ID: 0ff3c3fd-67c8-4c3f-94a2-bc2cd37df513 Received: from kvm5.telegraphics.com.au (unknown [98.124.60.144]) by us1-rack-iad1.inumbo.com (Halon) with ESMTP id 0ff3c3fd-67c8-4c3f-94a2-bc2cd37df513; Tue, 24 Nov 2020 02:48:38 +0000 (UTC) Received: from localhost (localhost.localdomain [127.0.0.1]) by kvm5.telegraphics.com.au (Postfix) with ESMTP id EF15F2AA0D; Mon, 23 Nov 2020 21:48:35 -0500 (EST) Date: Tue, 24 Nov 2020 13:48:34 +1100 (AEDT) From: Finn Thain To: Joe Perches cc: Miguel Ojeda , James Bottomley , Kees Cook , Jakub Kicinski , "Gustavo A. R. Silva" , linux-kernel , alsa-devel@alsa-project.org, amd-gfx@lists.freedesktop.org, bridge@lists.linux-foundation.org, ceph-devel@vger.kernel.org, cluster-devel@redhat.com, coreteam@netfilter.org, devel@driverdev.osuosl.org, dm-devel@redhat.com, drbd-dev@lists.linbit.com, dri-devel@lists.freedesktop.org, GR-everest-linux-l2@marvell.com, GR-Linux-NIC-Dev@marvell.com, intel-gfx@lists.freedesktop.org, intel-wired-lan@lists.osuosl.org, keyrings@vger.kernel.org, linux1394-devel@lists.sourceforge.net, linux-acpi@vger.kernel.org, linux-afs@lists.infradead.org, Linux ARM , linux-arm-msm@vger.kernel.org, linux-atm-general@lists.sourceforge.net, linux-block@vger.kernel.org, linux-can@vger.kernel.org, linux-cifs@vger.kernel.org, Linux Crypto Mailing List , linux-decnet-user@lists.sourceforge.net, Ext4 Developers List , linux-fbdev@vger.kernel.org, linux-geode@lists.infradead.org, linux-gpio@vger.kernel.org, linux-hams@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-i3c@lists.infradead.org, linux-ide@vger.kernel.org, linux-iio@vger.kernel.org, linux-input , linux-integrity@vger.kernel.org, linux-mediatek@lists.infradead.org, Linux Media Mailing List , linux-mmc@vger.kernel.org, Linux-MM , linux-mtd@lists.infradead.org, linux-nfs@vger.kernel.org, linux-rdma@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-sctp@vger.kernel.org, linux-security-module@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-usb@vger.kernel.org, linux-watchdog@vger.kernel.org, linux-wireless , Network Development , netfilter-devel@vger.kernel.org, nouveau@lists.freedesktop.org, op-tee@lists.trustedfirmware.org, oss-drivers@netronome.com, patches@opensource.cirrus.com, rds-devel@oss.oracle.com, reiserfs-devel@vger.kernel.org, samba-technical@lists.samba.org, selinux@vger.kernel.org, target-devel@vger.kernel.org, tipc-discussion@lists.sourceforge.net, usb-storage@lists.one-eyed-alien.net, virtualization@lists.linux-foundation.org, wcn36xx@lists.infradead.org, "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , xen-devel@lists.xenproject.org, linux-hardening@vger.kernel.org, Nick Desaulniers , Nathan Chancellor , Miguel Ojeda Subject: Re: [PATCH 000/141] Fix fall-through warnings for Clang In-Reply-To: Message-ID: References: <20201120105344.4345c14e@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <202011201129.B13FDB3C@keescook> <20201120115142.292999b2@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <202011220816.8B6591A@keescook> <9b57fd4914b46f38d54087d75e072d6e947cb56d.camel@HansenPartnership.com> MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII On Mon, 23 Nov 2020, Joe Perches wrote: > On Tue, 2020-11-24 at 11:58 +1100, Finn Thain wrote: > > it's not for me to prove that such patches don't affect code > > generation. That's for the patch author and (unfortunately) for > > reviewers. > > Ideally, that proof would be provided by the compilation system itself > and not patch authors nor reviewers nor maintainers. > > Unfortunately gcc does not guarantee repeatability or deterministic > output. To my knowledge, neither does clang. > Yes, I've said the same thing myself. But having attempted it, I now think this is a hard problem. YMMV. https://lore.kernel.org/linux-scsi/alpine.LNX.2.22.394.2004281017310.12@nippy.intranet/ https://lore.kernel.org/linux-scsi/alpine.LNX.2.22.394.2005211358460.8@nippy.intranet/