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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 2E221C433EF for ; Mon, 28 Feb 2022 18:41:02 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 63AA710E1B9; Mon, 28 Feb 2022 18:41:01 +0000 (UTC) Received: from mail-lf1-x131.google.com (mail-lf1-x131.google.com [IPv6:2a00:1450:4864:20::131]) by gabe.freedesktop.org (Postfix) with ESMTPS id 919FA10E192 for ; Mon, 28 Feb 2022 18:41:00 +0000 (UTC) Received: by mail-lf1-x131.google.com with SMTP id bu29so23061479lfb.0 for ; Mon, 28 Feb 2022 10:41:00 -0800 (PST) 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=B+acwbp8IAqy4EQhdzrRR6UrvnBSYJWdfAOCkLBEf6s=; b=LvJ51tK8OGXmUdrq1FTGfGhAU7kyWg6aDacet+/T6m1xcdm96SFLNin6cqkfGY+rbg A+4gdF9QL3th8X1CIPS6F2KrwGpjUcAkZFh2wMRAAEhyIS9gK5hzhXTjv7RRLGY5VhDN /ORnVKar4p0KNDioI7O/8vsyY3PJ0BwGF0c/w= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=B+acwbp8IAqy4EQhdzrRR6UrvnBSYJWdfAOCkLBEf6s=; b=rQ/UToh2Jgujf2RVMLexvBei4FUgunuvWEruS23Lx0JQwpAeaho/T4LhEHQBf3mhqs Vus8vOvywR1eM+PLsVvvRewEsmKbtgqwndbPwWpr8vWXdZzOBboq4K7fu+FRogDkX3Sg oZfbr188hom+S5+29A4tlDiggDK77MUHY+xnBn2NKFgU5QK1ThTIOEPi4t3AR7M3nl2W qlc1I0QVmvQjAoNReO9SNvTHPh3RAQDAIjVOHKQQc7ZWsTAoAFJRhTm1Pgt1Ea6BD7kJ EMspuyxG8s69dkG6WohSICIun6D7j+LcRQuEIYgnvQIehS++YIsm/LJdS3IWhWTenJHm DLWA== X-Gm-Message-State: AOAM531ZEvrC9QfZthry9/7ktDvel+42EzvVz4kK6j9ionVtGtBzk/W6 /OFMT9kmgC9kXtwYzyMG7pQ2mdVMAVnN+8YfAVk= X-Google-Smtp-Source: ABdhPJwLsa+ztivsm2NfYPIP+bKuEM2FsCt6oGnMUjT0+sY4W+9cjMZw08rw0TE+EHlNEgKHuKoB6w== X-Received: by 2002:ac2:5de4:0:b0:443:5b80:d4c4 with SMTP id z4-20020ac25de4000000b004435b80d4c4mr13345842lfq.373.1646073658414; Mon, 28 Feb 2022 10:40:58 -0800 (PST) Received: from mail-lf1-f54.google.com (mail-lf1-f54.google.com. [209.85.167.54]) by smtp.gmail.com with ESMTPSA id n13-20020a056512388d00b00443ecf806c5sm1083845lft.104.2022.02.28.10.40.55 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 28 Feb 2022 10:40:56 -0800 (PST) Received: by mail-lf1-f54.google.com with SMTP id t13so10936432lfd.9 for ; Mon, 28 Feb 2022 10:40:55 -0800 (PST) X-Received: by 2002:ac2:4c8c:0:b0:445:6c26:3cff with SMTP id d12-20020ac24c8c000000b004456c263cffmr13670491lfl.435.1646073655129; Mon, 28 Feb 2022 10:40:55 -0800 (PST) MIME-Version: 1.0 References: <20220228103142.3301082-1-arnd@kernel.org> In-Reply-To: From: Linus Torvalds Date: Mon, 28 Feb 2022 10:40:38 -0800 X-Gmail-Original-Message-ID: Message-ID: To: Arnd Bergmann Content-Type: text/plain; charset="UTF-8" Subject: Re: [Intel-gfx] [PATCH] [v2] Kbuild: move to -std=gnu11 X-BeenThere: intel-gfx@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Intel graphics driver community testing & development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Marco Elver , Michal Marek , "open list:DOCUMENTATION" , Arnd Bergmann , Jonathan Corbet , linux-staging@lists.linux.dev, Masahiro Yamada , llvm@lists.linux.dev, Nick Desaulniers , Linux Kernel Mailing List , dri-devel , greybus-dev@lists.linaro.org, Alex Shi , Federico Vaga , Hu Haowen , linux-btrfs , Intel Graphics , linux-doc-tw-discuss@lists.sourceforge.net, Linux Kbuild mailing list , Linux ARM Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" On Mon, Feb 28, 2022 at 3:37 AM Arnd Bergmann wrote: > > I think the KBUILD_USERCFLAGS portion and the modpost.c fix for it > make sense regardless of the -std=gnu11 change I do think they make sense, but I want to note again that people doing cross builds obviously use different tools for user builds than for the kernel. In fact, even not cross-building, we've had situations where the "kbuild" compiler is different from the host compiler, because people have upgraded one but not the other (upgrading the kernel build environment is actually much easier than upgrading the host build environment, because you don't need all the random libraries etc, and you can literally _just_ build your own gcc and binutils) And we have *not* necessarily required that the host tools match the kernel tools. So I could well imagine that there are people who build their kernels, but their host build environment might be old enough that -std=gnu11 is problematic for that part. And note how any change to KBUILD_USERCFLAGS is reflected in KBUILD_HOSTCFLAGS. So I would suggest that the KBUILD_USERCFLAGS part of the patch (and the modpost.c change that goes with it) be done as a separate commit. Because we might end up reverting that part. Hmm? Linus From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ej1-f49.google.com (mail-ej1-f49.google.com [209.85.218.49]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6AD2C15C1 for ; Mon, 28 Feb 2022 18:47:16 +0000 (UTC) Received: by mail-ej1-f49.google.com with SMTP id a23so26708782eju.3 for ; Mon, 28 Feb 2022 10:47:16 -0800 (PST) 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=B+acwbp8IAqy4EQhdzrRR6UrvnBSYJWdfAOCkLBEf6s=; b=LvJ51tK8OGXmUdrq1FTGfGhAU7kyWg6aDacet+/T6m1xcdm96SFLNin6cqkfGY+rbg A+4gdF9QL3th8X1CIPS6F2KrwGpjUcAkZFh2wMRAAEhyIS9gK5hzhXTjv7RRLGY5VhDN /ORnVKar4p0KNDioI7O/8vsyY3PJ0BwGF0c/w= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=B+acwbp8IAqy4EQhdzrRR6UrvnBSYJWdfAOCkLBEf6s=; b=qFDrpfkwk4G3yeHRQ267byrlVQSqNH591AP334GGN3r/w7dwtd7dBafiNLvh6AvJyf 4uyLKRcWaL07PBTBYE9tmTCVHXbb6ceyIGJUSyd0qnneUXnw9t4ecR9H1yuc2XPSYdGp 3YaJpvkp3Pmmu9bbZJxdCgiEuta85Q4GanUiWCo59FMRRscHPG1R47N9IWwrLXDI60hP +A8y5xbNVsdUFkWcXdk4AMDJk3oSGzj+94vJlng1kQwWDxksMJXr6v8Uhh0RJy/JtiR8 dmE3l9/1J46U6tv3qOD5r4mNG8eJ2ufFtgRDxpTO9oGqDFEDb2cssZJ1jHwtSCJdLheM MC4Q== X-Gm-Message-State: AOAM530N2NY4BxGOejlM0BH9Uo0oE7yEP0KlPpv+p3+qBIQGkXxCIDLb hXsEFZ2YTZsMN9VvYAP8fY8SIRCDihmVeE49jGQ= X-Google-Smtp-Source: ABdhPJxkYL3nqKaqt+trqpgpUQUUxQiXqamn02Oc2Zxk/76POf+63+pMykCoEIBhLlEzCfVZ0Y+EOg== X-Received: by 2002:a17:907:9043:b0:6cc:2e9d:233e with SMTP id az3-20020a170907904300b006cc2e9d233emr15542967ejc.53.1646074034476; Mon, 28 Feb 2022 10:47:14 -0800 (PST) Received: from mail-wr1-f53.google.com (mail-wr1-f53.google.com. [209.85.221.53]) by smtp.gmail.com with ESMTPSA id a8-20020a170906244800b006ce72bed2e5sm4653792ejb.143.2022.02.28.10.47.14 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 28 Feb 2022 10:47:14 -0800 (PST) Received: by mail-wr1-f53.google.com with SMTP id u1so16882630wrg.11 for ; Mon, 28 Feb 2022 10:47:14 -0800 (PST) X-Received: by 2002:ac2:4c8c:0:b0:445:6c26:3cff with SMTP id d12-20020ac24c8c000000b004456c263cffmr13670491lfl.435.1646073655129; Mon, 28 Feb 2022 10:40:55 -0800 (PST) Precedence: bulk X-Mailing-List: linux-staging@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 References: <20220228103142.3301082-1-arnd@kernel.org> In-Reply-To: From: Linus Torvalds Date: Mon, 28 Feb 2022 10:40:38 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] [v2] Kbuild: move to -std=gnu11 To: Arnd Bergmann Cc: Mark Rutland , Linux Kbuild mailing list , Arnd Bergmann , Masahiro Yamada , llvm@lists.linux.dev, Jonathan Corbet , Federico Vaga , Alex Shi , Hu Haowen , Michal Marek , Nick Desaulniers , "open list:DOCUMENTATION" , Linux Kernel Mailing List , linux-doc-tw-discuss@lists.sourceforge.net, Linux ARM , Intel Graphics , dri-devel , greybus-dev@lists.linaro.org, linux-staging@lists.linux.dev, linux-btrfs , Marco Elver Content-Type: text/plain; charset="UTF-8" On Mon, Feb 28, 2022 at 3:37 AM Arnd Bergmann wrote: > > I think the KBUILD_USERCFLAGS portion and the modpost.c fix for it > make sense regardless of the -std=gnu11 change I do think they make sense, but I want to note again that people doing cross builds obviously use different tools for user builds than for the kernel. In fact, even not cross-building, we've had situations where the "kbuild" compiler is different from the host compiler, because people have upgraded one but not the other (upgrading the kernel build environment is actually much easier than upgrading the host build environment, because you don't need all the random libraries etc, and you can literally _just_ build your own gcc and binutils) And we have *not* necessarily required that the host tools match the kernel tools. So I could well imagine that there are people who build their kernels, but their host build environment might be old enough that -std=gnu11 is problematic for that part. And note how any change to KBUILD_USERCFLAGS is reflected in KBUILD_HOSTCFLAGS. So I would suggest that the KBUILD_USERCFLAGS part of the patch (and the modpost.c change that goes with it) be done as a separate commit. Because we might end up reverting that part. Hmm? Linus 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 Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id D5B79C433EF for ; Mon, 28 Feb 2022 18:46:15 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 247D810E34F; Mon, 28 Feb 2022 18:46:15 +0000 (UTC) Received: from mail-ej1-x632.google.com (mail-ej1-x632.google.com [IPv6:2a00:1450:4864:20::632]) by gabe.freedesktop.org (Postfix) with ESMTPS id 57F6810E1D7 for ; Mon, 28 Feb 2022 18:46:14 +0000 (UTC) Received: by mail-ej1-x632.google.com with SMTP id d10so26678980eje.10 for ; Mon, 28 Feb 2022 10:46:14 -0800 (PST) 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=B+acwbp8IAqy4EQhdzrRR6UrvnBSYJWdfAOCkLBEf6s=; b=LvJ51tK8OGXmUdrq1FTGfGhAU7kyWg6aDacet+/T6m1xcdm96SFLNin6cqkfGY+rbg A+4gdF9QL3th8X1CIPS6F2KrwGpjUcAkZFh2wMRAAEhyIS9gK5hzhXTjv7RRLGY5VhDN /ORnVKar4p0KNDioI7O/8vsyY3PJ0BwGF0c/w= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=B+acwbp8IAqy4EQhdzrRR6UrvnBSYJWdfAOCkLBEf6s=; b=cPUk5N59UFq7QvDsNXQ4KYdtzu4tZW5mUbfEVH/xkauxev6OhkOZO2wSG9ea6ZmoFq 188H5GtfcLond38GB7AoJedXktkLkKdm25UZ/k4f05t7r0hyD4t842wbQgROIXyqd0JX 7I0gAh2btb45mZTU9pXKBSVyAEF5YUew/bFSamO4vqf8CeFMyfhNIhp5W5aUUnLnurG6 bf/D5aincnyxa+hPsUGcxaPkXfhBL6YqTE/h0lZpTWRwcDZGlffvScgKgHxadeaqJ0+0 LSsWBtHS5XrXClu2ibqovqDwP7CYP3Uj9swa3h/ynsz3o5JLVsh3sE2wZub7paGvknUV Ygqw== X-Gm-Message-State: AOAM5302zwoQQqf7SawAWMl0nIksnjD0MQNBQHPlH4CVrGbVcqqIv303 3gEIAXuN/V/pbO3aEOYRXujWIjLalTH5qrtMO5c= X-Google-Smtp-Source: ABdhPJxyLaQtSTuSikFRvCbu7YDrt7QGENNL8DfacR8dpCEYyvBWOOaILJ0n0Ttcb9baZEMKT/pSBw== X-Received: by 2002:a17:906:65d5:b0:6ba:3133:dfb9 with SMTP id z21-20020a17090665d500b006ba3133dfb9mr16603942ejn.56.1646073972362; Mon, 28 Feb 2022 10:46:12 -0800 (PST) Received: from mail-ej1-f50.google.com (mail-ej1-f50.google.com. [209.85.218.50]) by smtp.gmail.com with ESMTPSA id q16-20020a170906145000b006bdaf981589sm4611401ejc.81.2022.02.28.10.46.11 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 28 Feb 2022 10:46:11 -0800 (PST) Received: by mail-ej1-f50.google.com with SMTP id a23so26703304eju.3 for ; Mon, 28 Feb 2022 10:46:11 -0800 (PST) X-Received: by 2002:ac2:4c8c:0:b0:445:6c26:3cff with SMTP id d12-20020ac24c8c000000b004456c263cffmr13670491lfl.435.1646073655129; Mon, 28 Feb 2022 10:40:55 -0800 (PST) MIME-Version: 1.0 References: <20220228103142.3301082-1-arnd@kernel.org> In-Reply-To: From: Linus Torvalds Date: Mon, 28 Feb 2022 10:40:38 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] [v2] Kbuild: move to -std=gnu11 To: Arnd Bergmann Content-Type: text/plain; charset="UTF-8" X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Marco Elver , Michal Marek , "open list:DOCUMENTATION" , Arnd Bergmann , Jonathan Corbet , linux-staging@lists.linux.dev, Masahiro Yamada , llvm@lists.linux.dev, Nick Desaulniers , Linux Kernel Mailing List , dri-devel , greybus-dev@lists.linaro.org, Alex Shi , Federico Vaga , Hu Haowen , linux-btrfs , Intel Graphics , linux-doc-tw-discuss@lists.sourceforge.net, Linux Kbuild mailing list , Linux ARM Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Mon, Feb 28, 2022 at 3:37 AM Arnd Bergmann wrote: > > I think the KBUILD_USERCFLAGS portion and the modpost.c fix for it > make sense regardless of the -std=gnu11 change I do think they make sense, but I want to note again that people doing cross builds obviously use different tools for user builds than for the kernel. In fact, even not cross-building, we've had situations where the "kbuild" compiler is different from the host compiler, because people have upgraded one but not the other (upgrading the kernel build environment is actually much easier than upgrading the host build environment, because you don't need all the random libraries etc, and you can literally _just_ build your own gcc and binutils) And we have *not* necessarily required that the host tools match the kernel tools. So I could well imagine that there are people who build their kernels, but their host build environment might be old enough that -std=gnu11 is problematic for that part. And note how any change to KBUILD_USERCFLAGS is reflected in KBUILD_HOSTCFLAGS. So I would suggest that the KBUILD_USERCFLAGS part of the patch (and the modpost.c change that goes with it) be done as a separate commit. Because we might end up reverting that part. Hmm? Linus 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 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id F14FAC433F5 for ; Mon, 28 Feb 2022 18:49:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; 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=Gk5EG7uySDqhCTA55drKMmLeWhDGu+0gW/tprIG+R0Q=; b=szfj0m8E3xTrEw hllKMPPSG5V+kxqKeB9AmQ6jlIXRYtwZ5ETqKJjiQo0WMmiZxQrAAEjmmEL/ExRGMpi8+TaRo5y+w 4nHqyH5bE2zByIfOvR9QXafIK1LpNXo3CwMTqbL5zAFibfkG8R9vN9CS3MpdzxX+4BsWYR51QLiQy jRgki9F7rnADpcTDB1glbFpMtcKShU1spqIVAA56c+Eh4/u/PvYON36W3p9CxzP3BlKpA/shsBwo7 1wxT1LvGRAPcu7cCPKpJMzYpvbr7psob0U4ehbeo8Ui+2pbbsvtyn/wv/QolSwooQwV22pYVnE+D4 zHvKixdZzUss+h2LlOhA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nOl2x-00Dk6a-FJ; Mon, 28 Feb 2022 18:46:59 +0000 Received: from mail-ej1-x62f.google.com ([2a00:1450:4864:20::62f]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nOl2t-00Dk6A-Tu for linux-arm-kernel@lists.infradead.org; Mon, 28 Feb 2022 18:46:57 +0000 Received: by mail-ej1-x62f.google.com with SMTP id p14so26662177ejf.11 for ; Mon, 28 Feb 2022 10:46:55 -0800 (PST) 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=B+acwbp8IAqy4EQhdzrRR6UrvnBSYJWdfAOCkLBEf6s=; b=LvJ51tK8OGXmUdrq1FTGfGhAU7kyWg6aDacet+/T6m1xcdm96SFLNin6cqkfGY+rbg A+4gdF9QL3th8X1CIPS6F2KrwGpjUcAkZFh2wMRAAEhyIS9gK5hzhXTjv7RRLGY5VhDN /ORnVKar4p0KNDioI7O/8vsyY3PJ0BwGF0c/w= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=B+acwbp8IAqy4EQhdzrRR6UrvnBSYJWdfAOCkLBEf6s=; b=KTvcDfzX8kC0ON9P86JaLraoij+2tdT22C1q+LJ3K++3eiMjGaPdblc4Uohp1oGeDW 3s7fqx8YCPEIBtTuYRYJzWG0jkG99/odrOnTZ1fQNJ28udNDUhojr0XGghrWtVTkQckq 368SnmgHyqIiIioEc7c2Xz+/AH03Y255OUsWjLqE6YLpGbd+ymZupy6IrZ5RM6bIO0Vd 9Ml2EgrAT9/+YbHhlraJytajp3KLQaZkrkkWkMp96T6ykEfxJQWEZsUOLAKkU7GRIZju im6plbKFJBS0ArMuHCBVCSUC7CZid9mhqje4uVG1FXAwG8cHfuOBngwQWpxK0qcNG+Nr Euxg== X-Gm-Message-State: AOAM531B1PiMLPty3++kUTf+8lKEZky9g9mwEWw89GtHI3Gbdxz/1pOY x8KJNulCm/rRX5xiTC4qyfTXVbdpgpB8A4TNA+k= X-Google-Smtp-Source: ABdhPJwU87h15jFFYHjNjmmTMQKHw8+vxkcnrmbeIrZDQJvP1jAHfFSZaS85dVmjJLpYJ9e8Hq1WtQ== X-Received: by 2002:a17:906:edbd:b0:6b6:bd54:235c with SMTP id sa29-20020a170906edbd00b006b6bd54235cmr16240389ejb.363.1646074013910; Mon, 28 Feb 2022 10:46:53 -0800 (PST) Received: from mail-ej1-f41.google.com (mail-ej1-f41.google.com. [209.85.218.41]) by smtp.gmail.com with ESMTPSA id f6-20020a50fc86000000b0040f614e0906sm6371022edq.46.2022.02.28.10.46.53 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 28 Feb 2022 10:46:53 -0800 (PST) Received: by mail-ej1-f41.google.com with SMTP id hw13so26658231ejc.9 for ; Mon, 28 Feb 2022 10:46:53 -0800 (PST) X-Received: by 2002:ac2:4c8c:0:b0:445:6c26:3cff with SMTP id d12-20020ac24c8c000000b004456c263cffmr13670491lfl.435.1646073655129; Mon, 28 Feb 2022 10:40:55 -0800 (PST) MIME-Version: 1.0 References: <20220228103142.3301082-1-arnd@kernel.org> In-Reply-To: From: Linus Torvalds Date: Mon, 28 Feb 2022 10:40:38 -0800 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH] [v2] Kbuild: move to -std=gnu11 To: Arnd Bergmann Cc: Mark Rutland , Linux Kbuild mailing list , Arnd Bergmann , Masahiro Yamada , llvm@lists.linux.dev, Jonathan Corbet , Federico Vaga , Alex Shi , Hu Haowen , Michal Marek , Nick Desaulniers , "open list:DOCUMENTATION" , Linux Kernel Mailing List , linux-doc-tw-discuss@lists.sourceforge.net, Linux ARM , Intel Graphics , dri-devel , greybus-dev@lists.linaro.org, linux-staging@lists.linux.dev, linux-btrfs , Marco Elver X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220228_104655_982498_462CB8DD X-CRM114-Status: GOOD ( 15.83 ) 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 Mon, Feb 28, 2022 at 3:37 AM Arnd Bergmann wrote: > > I think the KBUILD_USERCFLAGS portion and the modpost.c fix for it > make sense regardless of the -std=gnu11 change I do think they make sense, but I want to note again that people doing cross builds obviously use different tools for user builds than for the kernel. In fact, even not cross-building, we've had situations where the "kbuild" compiler is different from the host compiler, because people have upgraded one but not the other (upgrading the kernel build environment is actually much easier than upgrading the host build environment, because you don't need all the random libraries etc, and you can literally _just_ build your own gcc and binutils) And we have *not* necessarily required that the host tools match the kernel tools. So I could well imagine that there are people who build their kernels, but their host build environment might be old enough that -std=gnu11 is problematic for that part. And note how any change to KBUILD_USERCFLAGS is reflected in KBUILD_HOSTCFLAGS. So I would suggest that the KBUILD_USERCFLAGS part of the patch (and the modpost.c change that goes with it) be done as a separate commit. Because we might end up reverting that part. Hmm? Linus _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel