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=-12.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham 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 E3E94C433DB for ; Thu, 14 Jan 2021 07:40:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BA0D2238E7 for ; Thu, 14 Jan 2021 07:40:24 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727518AbhANHkE (ORCPT ); Thu, 14 Jan 2021 02:40:04 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33226 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727377AbhANHkD (ORCPT ); Thu, 14 Jan 2021 02:40:03 -0500 Received: from mail-io1-xd30.google.com (mail-io1-xd30.google.com [IPv6:2607:f8b0:4864:20::d30]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D2390C061786; Wed, 13 Jan 2021 23:39:22 -0800 (PST) Received: by mail-io1-xd30.google.com with SMTP id o6so9347296iob.10; Wed, 13 Jan 2021 23:39:22 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:reply-to:from:date:message-id :subject:to:cc; bh=pDkl50wKKXvlnFEMyoCOA4eiXkVtCkofqFa11F/2prs=; b=LZyONW5l41afxbiMWOMOs2HO+Ycvj/ZhU6K3xVqaHgQmQgTGvC1VQ1gc6kVTsnGFKJ cmL7EHu+N03GO+52M3MV2CNuYp5od3c08tcT4hFsrAZpMZ3bmTUxl8b+L7yv4UNwPdU+ TvSw9dtuJ/2nVUNZlFoy1x22WzDToEqa8CQB8oUIaZRUkFbzU51MT90mThiwyeodhDZM 0f2nX0dcifQEi3DsWP81K2g5pcFZpilE/644iPlx2Ie6SraPNbekg18NWSylqf0BSYCt /zrNRyt0B9abhw5pPdskxkXdremW4yHbcGPAr1aOBU+8Q9SfhmmByiTZ45JdMzj+IzMQ pJTA== 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:reply-to :from:date:message-id:subject:to:cc; bh=pDkl50wKKXvlnFEMyoCOA4eiXkVtCkofqFa11F/2prs=; b=SMXAXCxx2a9ipsBYY9Fw+bNmiyoR2HgGBuVUcjdkLKQo2AXb9xM3itEqUI7ptHhG58 XJdsT9ntvH6ORA4owA5YBawiSTZQuxhOPX/8KyqEHK+Blv+wWnh53neF4wMRjSdaVfdG NyByoa2JgoG/IS9TEFhXkKCflRxH01O+Qgzbz+ZKQv63wsbrA2Dk7p/BYSXA30KMiTkS 1kNH4r8d/czRl4ifGQ4Xl3F+F6BVUr073nC5Q2ttOF/spPLA2BSVHVpJTLJB1StvCgNR zVia1aSMI6uzyT/VEWi+eZigYISGXjmUlu1O2Ahp/V2yFvtgmXZ0psuJmeHbyRn1ZTK0 x5MA== X-Gm-Message-State: AOAM5337QjXeKf3nFZpEZJNw19wStoy9J3UiIwcIKEmLF9nDds/XVdiS kC0YuZT1uEzXv7lj6t69tazX+QAbZP8cBHtfB2I= X-Google-Smtp-Source: ABdhPJybXK0BLNSRQ7Ixe4ZXs/7KsiW13lw8MOehz5t9ImRNCgGZwZITi4quK9lNA4M+jLD8VYG7wr74zmhPCg8g1f8= X-Received: by 2002:a92:d990:: with SMTP id r16mr5718971iln.10.1610609962241; Wed, 13 Jan 2021 23:39:22 -0800 (PST) MIME-Version: 1.0 References: <20210114003447.7363-1-natechancellor@gmail.com> In-Reply-To: <20210114003447.7363-1-natechancellor@gmail.com> Reply-To: sedat.dilek@gmail.com From: Sedat Dilek Date: Thu, 14 Jan 2021 08:39:11 +0100 Message-ID: Subject: Re: [PATCH] Documentation/llvm: Add a section about supported architectures To: Nathan Chancellor Cc: Nick Desaulniers , Masahiro Yamada , Michal Marek , Jonathan Corbet , Clang-Built-Linux ML , linux-kbuild@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org, Miguel Ojeda Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Jan 14, 2021 at 1:35 AM Nathan Chancellor wrote: > > The most common question around building the Linux kernel with clang is > "does it work?" and the answer has always been "it depends on your > architecture, configuration, and LLVM version" with no hard answers for > users wanting to experiment. LLVM support has significantly improved > over the past couple of years, resulting in more architectures and > configurations supported, and continuous integration has made it easier > to see what works and what does not. > > Add a section that goes over what architectures are supported in the > current kernel version, how they should be built (with just clang or the > LLVM utilities as well), and the level of support they receive. This > will make it easier for people to try out building their kernel with > LLVM and reporting issues that come about from it. > Thanks, this was overdue and is definitely helpful for users and developers. For x86 64bit: Reviewed-by: Sedat Dilek Together with "[PATCH] kbuild: check the minimum compiler version in Kconfig" this looks very good to me. /o\ - Sedat - [1] https://marc.info/?t=161059811000001&r=1&w=2 > Suggested-by: Miguel Ojeda > Signed-off-by: Nathan Chancellor > --- > Documentation/kbuild/llvm.rst | 44 +++++++++++++++++++++++++++++++++++ > 1 file changed, 44 insertions(+) > > diff --git a/Documentation/kbuild/llvm.rst b/Documentation/kbuild/llvm.rst > index 21c847890d03..b18401d2ba82 100644 > --- a/Documentation/kbuild/llvm.rst > +++ b/Documentation/kbuild/llvm.rst > @@ -63,6 +63,50 @@ They can be enabled individually. The full list of the parameters: :: > Currently, the integrated assembler is disabled by default. You can pass > ``LLVM_IAS=1`` to enable it. > > +Supported Architectures > +----------------------- > + > +LLVM does not target all of the architectures that Linux supports and > +just because a target is supported in LLVM does not mean that the kernel > +will build or work without any issues. Below is a general summary of > +architectures that currently work with ``CC=clang`` or ``LLVM=1``. Level > +of support corresponds to "S" values in the MAINTAINERS files. If an > +architecture is not present, it either means that LLVM does not target > +it or there are known issues. Using the latest stable version of LLVM or > +even the development tree will generally yield the best results. > +An architecture's ``defconfig`` is generally expected to work well, > +certain configurations may have problems that have not been uncovered > +yet. Bug reports are always welcome at the issue tracker below! > + > +.. list-table:: > + :widths: 10 10 10 > + :header-rows: 1 > + > + * - Architecture > + - Level of support > + - ``make`` command > + * - arm > + - Supported > + - ``LLVM=1`` > + * - arm64 > + - Supported > + - ``LLVM=1`` > + * - mips > + - Maintained > + - ``CC=clang`` > + * - powerpc > + - Maintained > + - ``CC=clang`` > + * - riscv > + - Maintained > + - ``CC=clang`` > + * - s390 > + - Maintained > + - ``CC=clang`` > + * - x86 > + - Supported > + - ``LLVM=1`` > + > Getting Help > ------------ > > > base-commit: 7c53f6b671f4aba70ff15e1b05148b10d58c2837 > -- > 2.30.0 > > -- > You received this message because you are subscribed to the Google Groups "Clang Built Linux" group. > To unsubscribe from this group and stop receiving emails from it, send an email to clang-built-linux+unsubscribe@googlegroups.com. > To view this discussion on the web visit https://groups.google.com/d/msgid/clang-built-linux/20210114003447.7363-1-natechancellor%40gmail.com.