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 AE1A2C8301B for ; Sun, 22 Nov 2020 22:55:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7CB1420773 for ; Sun, 22 Nov 2020 22:55:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726293AbgKVWyy (ORCPT ); Sun, 22 Nov 2020 17:54:54 -0500 Received: from kvm5.telegraphics.com.au ([98.124.60.144]:50556 "EHLO kvm5.telegraphics.com.au" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725782AbgKVWyx (ORCPT ); Sun, 22 Nov 2020 17:54:53 -0500 Received: from localhost (localhost.localdomain [127.0.0.1]) by kvm5.telegraphics.com.au (Postfix) with ESMTP id BF98E29DB3; Sun, 22 Nov 2020 17:54:47 -0500 (EST) Date: Mon, 23 Nov 2020 09:54:48 +1100 (AEDT) From: Finn Thain To: Miguel Ojeda cc: 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 , Joe Perches 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 Precedence: bulk List-ID: X-Mailing-List: linux-block@vger.kernel.org On Sun, 22 Nov 2020, Miguel Ojeda wrote: > > It isn't that much effort, isn't it? Plus we need to take into account > the future mistakes that it might prevent, too. We should also take into account optimisim about future improvements in tooling. > So even if there were zero problems found so far, it is still a positive > change. > It is if you want to spin it that way. > I would agree if these changes were high risk, though; but they are > almost trivial. > This is trivial: case 1: this(); + fallthrough; case 2: that(); But what we inevitably get is changes like this: case 3: this(); + break; case 4: hmmm(); Why? Mainly to silence the compiler. Also because the patch author argued successfully that they had found a theoretical bug, often in mature code. But is anyone keeping score of the regressions? If unreported bugs count, what about unreported regressions? > Cheers, > Miguel >