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=-4.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,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 243BBC433B4 for ; Sun, 2 May 2021 21:10:24 +0000 (UTC) Received: from desiato.infradead.org (desiato.infradead.org [90.155.92.199]) (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 92A0C6112F for ; Sun, 2 May 2021 21:10:23 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 92A0C6112F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=desiato.20200630; h=Sender:Content-Transfer-Encoding :Content-Type:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:Cc:To:Subject:Message-ID:Date:From:In-Reply-To: References:MIME-Version:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=bxhx0dZd1QgOrB/S1AK2cfTzicJxYvDJLzQkXMfnSyg=; b=i1LuAD1YLybXqwqMYurVPqo+m JBgureaXogrmzoIE/5fBDUVoYIO/DoXPzdXE0syhipPtf61FMQbFgZ0308S+izJy4/vYQlTXAWeoa 6Ztlg/n7ElnI7ZdOM174JZZRxbLqvfuRTSAPxHjVArWzUxZF0MuDD/rROYpCqbRsQ3W06HfKWkwqT 5eP9PNW5IEnYbquFHgO9bEsZ/8DtMrI92xy3FiRhHwAZiznII3J4yTQH/3IOHLDWDjKebXvsBk67s V4ANUjvtAs6067CDzi5MoD834sijsNTsC7CyQtgi4oXx/oXJbwN9rjbs5rMaAhEopfU1wD316Ysav 5x5kvRF9g==; Received: from localhost ([::1] helo=desiato.infradead.org) by desiato.infradead.org with esmtp (Exim 4.94 #2 (Red Hat Linux)) id 1ldJKj-00CUKk-3f; Sun, 02 May 2021 21:08:57 +0000 Received: from bombadil.infradead.org ([2607:7c80:54:e::133]) by desiato.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1ldJKf-00CUKJ-R4 for linux-arm-kernel@desiato.infradead.org; Sun, 02 May 2021 21:08:54 +0000 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Content-Type:Cc:To:Subject:Message-ID :Date:From:In-Reply-To:References:MIME-Version:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=ztLe0PUCKTK2LtdP2HGMOWnOHEgLtC71r4QQFdpNTzw=; b=cUv8XVXvn2SeCFlM18xdScY5oO XGs3R3Bt5MPutHv2VDTDyzPcvAvjOpfkS3O90Wk3sGgcR9CIgMGael6F5C8itOibGd7WVu4J4Ke7v G+PizJTxRaQ8EhTr+tm82RR9f1Lvv9Nk/a7dhzCPrYFDTH89iR42kFjqgnuN1Hkz1XWyAQ3Fg4+tU vj1sk+ByLHbvIYHdMxpMUCvhOX0MRnP6Cb4+14Xses2Pw9rIjgPL5wxqejF1D6Ccxw76luMx+gvcF MAKssQXLCQ95bAicTHhjkQ8CV7Y8A8JaWQyaszOnxjJF4GuC4M2kr3mGfKr88Di93ukwdXs4niWxS VvM0Cg0A==; Received: from mail-lf1-x134.google.com ([2a00:1450:4864:20::134]) by bombadil.infradead.org with esmtps (Exim 4.94 #2 (Red Hat Linux)) id 1ldJKd-002gld-3k for linux-arm-kernel@lists.infradead.org; Sun, 02 May 2021 21:08:52 +0000 Received: by mail-lf1-x134.google.com with SMTP id j4so5264174lfp.0 for ; Sun, 02 May 2021 14:08:50 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=ztLe0PUCKTK2LtdP2HGMOWnOHEgLtC71r4QQFdpNTzw=; b=YBiD6aB1h/sCqYhKTphH+dg0wIZGGo6mw2O+h2UbBPaKs2j+amxCQcnTb6T4EcSFDi 569RK7dsnKNOuJGN1Zq3Sl1+5gAq1k0k2Eo073vJURqtQ79ulv+UTiBKQN1QHx0TnXJL 8kMigLRMuOZq6Z9mW4YA2S0oPDLTJFBkJG6AU= 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=ztLe0PUCKTK2LtdP2HGMOWnOHEgLtC71r4QQFdpNTzw=; b=eKMD99+sGHCX4Aj6oDcSK+5qqjy0xihzNOOuxTCbLbpVn/GhuYEcaXwRj2FWel2FOH nUCUp+Ikr+SLWbisun/k21hPsLwZVrvo3ZEgJOUHqFtTKNoZM0yr6UBUK3dmfHTmZbDr pU+ow9H+Wr1JSKtFbPpthL4uE7VOsW8bzyWR+NAVTYL+1NKFdYMYBl9WkoXxxbZGr1Uk kf6Xn7IZ9Sax0bzflEGpc8ZXeXY9zGHbKl45NY01/cJnl+jVOelXuci6YHVmSpl6Evhm zrivyzhu70Gs1ihY3No13LkdnwwkTHikUpfbT3xIRS8aBsD6bIFu5fLQ/MSiLhZ6BeeT Syxw== X-Gm-Message-State: AOAM5325mMtrVH2kyGHlERoyfwqzX8S9orwrnbXANQlow3tVuJ3NpSiN WGXb5yR82xPGUxEtGP0FCH1jo+N3ayZJT6b4 X-Google-Smtp-Source: ABdhPJx3piWgm8QixbWpPo5rOMtEkvd+7IHhPWxg2QL1aY0UpOrqc3zlzE5RerHTu8rGfbhM5fSQEA== X-Received: by 2002:a19:ca04:: with SMTP id a4mr11913476lfg.588.1619989728728; Sun, 02 May 2021 14:08:48 -0700 (PDT) Received: from mail-lj1-f182.google.com (mail-lj1-f182.google.com. [209.85.208.182]) by smtp.gmail.com with ESMTPSA id z4sm1034615ljk.1.2021.05.02.14.08.47 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 02 May 2021 14:08:47 -0700 (PDT) Received: by mail-lj1-f182.google.com with SMTP id d15so4482066ljo.12 for ; Sun, 02 May 2021 14:08:47 -0700 (PDT) X-Received: by 2002:a2e:330f:: with SMTP id d15mr11126850ljc.251.1619989727157; Sun, 02 May 2021 14:08:47 -0700 (PDT) MIME-Version: 1.0 References: <20210501151538.145449-1-masahiroy@kernel.org> <3943bc020f6227c8801907317fc113aa13ad4bad.camel@perches.com> <20210502183030.GF10366@gate.crashing.org> <81a926a3bdb70debe3ae2b13655ea8d249fb9991.camel@perches.com> <20210502203253.GH10366@gate.crashing.org> In-Reply-To: <20210502203253.GH10366@gate.crashing.org> From: Linus Torvalds Date: Sun, 2 May 2021 14:08:31 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] Raise the minimum GCC version to 5.2 To: Segher Boessenkool Cc: Joe Perches , Miguel Ojeda , Masahiro Yamada , Albert Ou , Arnd Bergmann , Linux Kbuild mailing list , Greg Kroah-Hartman , Jonathan Corbet , Linux Doc Mailing List , linux-kernel , Palmer Dabbelt , Paul Walmsley , Catalin Marinas , Miguel Ojeda , Paul Mackerras , linux-riscv@lists.infradead.org, linuxppc-dev , Will Deacon , Linux ARM X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210502_140851_176896_7B48E28C X-CRM114-Status: GOOD ( 19.91 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Sun, May 2, 2021 at 1:38 PM Segher Boessenkool wrote: > > The point is, you inconvenience users if you require a compiler version > they do not already have. Five years might be fine, but three years is > not. So this should be our main issue - not how old a compiler is, but how our compiler version limitations end up possibly making it harder for users to upgrade. Of course, one issue there is whether said users would have upgraded regardless - if you have a very old distribution, how likely are you to upgrade the kernel at all? But we do very much want to encourage people to upgrade their kernels, even if they might be running otherwise fairly old user space. If for no other reason than that it's good for our kernel coverage testing - the more different distributions people test a new kernel with, the better. And some of the less common architectures have their own issues, with distros possibly not even supporting them any more (if they ever did - considering all the odd ad-hoc cross-compiler builds people have had..) This is why "our clang support requires a very recent version of clang" is not relevant - distributions won't have old versions of clang anyway, and even if they do, such distributions will be gcc-based, so "build the kernel with clang" for that situation is perhaps an exercise for some intrepid person who is willing to do odd and unusual things, and might as well build their own clang version too. So I really wish people didn't get hung about some "three years ago" or similar. It's not relevant. What is relevant is what version of gcc various distributions actually have reasonably easily available, and how old and relevant the distributions are. We did decide that (just as an example) RHEL 7 was too old to worry about when we updated the gcc version requirement last time. Last year, Arnd and Kirill (maybe others were involved too) made a list of distros and older gcc versions. But I don't think anybody actually _maintains_ such a list. It would be perhaps interesting to have some way to check what compiler versions are being offered by different distros. Linus _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel