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=-2.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED 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 F17E5C63798 for ; Thu, 26 Nov 2020 17:06:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AD23F2145D for ; Thu, 26 Nov 2020 17:06:22 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="YymqsvqK" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2404129AbgKZRGA (ORCPT ); Thu, 26 Nov 2020 12:06:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34004 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2391424AbgKZRF7 (ORCPT ); Thu, 26 Nov 2020 12:05:59 -0500 Received: from mail-yb1-xb2d.google.com (mail-yb1-xb2d.google.com [IPv6:2607:f8b0:4864:20::b2d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 04566C0613D4; Thu, 26 Nov 2020 09:05:57 -0800 (PST) Received: by mail-yb1-xb2d.google.com with SMTP id x17so2187795ybr.8; Thu, 26 Nov 2020 09:05:57 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=O/jaIJrbif54isUECHds/J8Ujq0NdoNxUTCCwJWwQ80=; b=YymqsvqKytU8xghgrWvO9q2MBm/qo/QfMLfSKpWw4/r/4uRHhZxuPq9ek+nW3ctzYi vs3zi1yLEuFoGUDgrnF15wpJAK9RqJ1aO9sTXa0PjOzjLe+d4O/pTFiiO013Mx2qKoL4 SkUMUUIjag5bjqwHGLYc9f20TwOaOWbGTale/6i8ahvnaZymX26ArF3ReuQKFVdof495 iKDDkr6mQvIIbdynQAd2wxd2GUAuBku/vDm4jIdtOw4Ph7wkJ5rD2TxigEVm3yQ5C9tu pJCfZKqtAfLebSyeKrm6VDCN2G4oKvj4TFU9uFOnavPNoLjuB5eIt+ODZ6yyvDDDthAD GeSQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=O/jaIJrbif54isUECHds/J8Ujq0NdoNxUTCCwJWwQ80=; b=ScBlCqi4skIArtaR4kQcEReg7TVxKUYNW4pi4FYLC5rulM07nX25oVtlH/2cTnijF4 TtBFON/rzKW94Se+Uip6M9QpoTkK+i4836J+lKBHdIRVhoL0mQ+dnVmSEUi1/rYYfEp4 odTvu+JuN/BrJBeO3W4MTXOlQ0kgzBctn3igcF0Vox/QNuBn7Op2XN35D7PtLUe52jHL xQlR/iGtM+WK1yK0IRO3HQhU7L9VqgSbFCrlwhc0uQWK9eUG6TmYm2dONVvQuX3qSsxF 4kHEyPc2drxo/eXh9+7ViWb2b5VcBaL35fPogGuJZZJwnYUk32JWBWIyqMptzG2vSMri plRg== X-Gm-Message-State: AOAM532PwbWdlo7rWyap8WUQBVbMWdhlBwS/33tpH4BVpsBrz8rDOGGu YTPyy/jp37XbILz2iM+bvXdY+A6oHTD1VECges4= X-Google-Smtp-Source: ABdhPJxMy5ncXEZ6TSWkZ0cAXTnkQ7iw+jjdg+cNNUWTZPlZcmFMrQQcJd2JAoeBontKFrtwmzLazAacI3fdsjx9xvQ= X-Received: by 2002:a5b:40e:: with SMTP id m14mr4835621ybp.33.1606410357153; Thu, 26 Nov 2020 09:05:57 -0800 (PST) MIME-Version: 1.0 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> <1c7d7fde126bc0acf825766de64bf2f9b888f216.camel@HansenPartnership.com> <4993259d01a0064f8bb22770503490f9252f3659.camel@HansenPartnership.com> <44005bde-f6d4-5eaa-39b8-1a5efeedb2d3@gmail.com> In-Reply-To: From: Miguel Ojeda Date: Thu, 26 Nov 2020 18:05:45 +0100 Message-ID: Subject: Re: [PATCH 000/141] Fix fall-through warnings for Clang To: Geert Uytterhoeven Cc: Edward Cree , ALSA Development Mailing List , linux-atm-general@lists.sourceforge.net, reiserfs-devel@vger.kernel.org, linux-iio@vger.kernel.org, linux-wireless , Linux Fbdev development list , dri-devel , "Gustavo A. R. Silva" , James Bottomley , linux-ide@vger.kernel.org, dm-devel@redhat.com, keyrings@vger.kernel.org, MTD Maling List , GR-everest-linux-l2@marvell.com, wcn36xx@lists.infradead.org, samba-technical@lists.samba.org, linux-i3c@lists.infradead.org, linux1394-devel@lists.sourceforge.net, linux-afs@lists.infradead.org, usb-storage@lists.one-eyed-alien.net, Lars Ellenberg , driverdevel , linux-cifs@vger.kernel.org, rds-devel@oss.oracle.com, Nick Desaulniers , scsi , Nathan Chancellor , linux-rdma , oss-drivers@netronome.com, bridge@lists.linux-foundation.org, linux-security-module , amd-gfx list , linux-stm32@st-md-mailman.stormreply.com, cluster-devel@redhat.com, ACPI Devel Maling List , coreteam@netfilter.org, intel-wired-lan@lists.osuosl.org, linux-input , Miguel Ojeda , Jakub Kicinski , Ext4 Developers List , Linux Media Mailing List , Kees Cook , selinux@vger.kernel.org, linux-arm-msm , Intel Graphics Development , linux-geode@lists.infradead.org, linux-can@vger.kernel.org, linux-block@vger.kernel.org, "open list:GPIO SUBSYSTEM" , op-tee@lists.trustedfirmware.org, linux-mediatek@lists.infradead.org, xen-devel@lists.xenproject.org, Nouveau Dev , linux-hams@vger.kernel.org, ceph-devel , virtualization@lists.linux-foundation.org, Linux ARM , linux-hwmon@vger.kernel.org, Linux Watchdog Mailing List , "open list:NFS, SUNRPC, AND..." , GR-Linux-NIC-Dev@marvell.com, tipc-discussion@lists.sourceforge.net, Linux-MM , Network Development , linux-decnet-user@lists.sourceforge.net, Linux MMC List , linux-kernel , "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , Linux-Renesas , linux-sctp@vger.kernel.org, USB list , NetFilter , Linux Crypto Mailing List , patches@opensource.cirrus.com, Joe Perches , linux-integrity , target-devel , linux-hardening@vger.kernel.org Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-sctp@vger.kernel.org On Thu, Nov 26, 2020 at 4:28 PM Geert Uytterhoeven wrote: > > The maintainer is not necessarily the owner/author of the code, and > thus may not know the intent of the code. Agreed, I was not blaming maintainers -- just trying to point out that the problem is there :-) In those cases, it is still very useful: we add the `fallthrough` and a comment saying `FIXME: fallthrough intended? Figure this out...`. Thus a previous unknown unknown is now a known unknown. And no new unknown unknowns will be introduced since we enabled the warning globally. > BTW, you cannot mindlessly fix the latter, as you cannot know if > "(a == b)" or "((a = b))" was intended, without understanding the code > (and the (possibly unavailable) data sheet, and the hardware, ...). That's right, I was referring to the cases where the compiler saves someone time from a typo they just made. Cheers, Miguel