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=-2.4 required=3.0 tests=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,USER_AGENT_MUTT 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 457DCC04AB6 for ; Sat, 1 Jun 2019 00:29:04 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 14F992708E for ; Sat, 1 Jun 2019 00:29:04 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="g7AQ2p/R" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726917AbfFAA3D (ORCPT ); Fri, 31 May 2019 20:29:03 -0400 Received: from mail-ed1-f68.google.com ([209.85.208.68]:36019 "EHLO mail-ed1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725883AbfFAA3C (ORCPT ); Fri, 31 May 2019 20:29:02 -0400 Received: by mail-ed1-f68.google.com with SMTP id a8so17117734edx.3 for ; Fri, 31 May 2019 17:29:01 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to:user-agent; bh=JNA+M2HNg5wC58bq9MZMCh6YyzsCVe0fiW59+AoI+uk=; b=g7AQ2p/RBhEEwukGt++EPQDzHYe3xAanZFkwZbDE2W/aOJnnVSHjYYJyumy9E3fGIK MOYIQP5P9hNJ/8I6BMNJauiYurLi7++SWUKkh10Q0nWDqa9uayZhElnX4el7hGmqoNvQ U7uDj2Hrst9GJYcVKnfWPPlSLGRmh66qyJC8yFR3EgO6/8uK/fwbLtw2klXXCQaeRD8/ cAOBe+wMbSvjmTJrdxom7WKJ/rNw/wJEXVVro9JNLuP15MDMgzMFcESSm4cOTSUSbSKn h8IjqqdAea5IqczJoAirb11KMsrKfU/IZIVZODIfcvwgHHbdNwEoNCf5v/lUFY04XvUp O2sw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to:user-agent; bh=JNA+M2HNg5wC58bq9MZMCh6YyzsCVe0fiW59+AoI+uk=; b=oKIR9DKWWLdoAEmUG9P01q/THR+GNtNVQgatyEZtGydU3Q8b3FVnN1zalthuX/8kx/ gAtDk6/1cu2JwBrg9UWUqoi7/B30a0FjAv9iC+0aylW1/2ikEcuRStv4JhSoSfQGoRzX rJKL8KrKohzjIAcBPMNFu+E8zgdZpW+IE1HY8SUHoRKZKrh0qDQ6oe1PeU4XkbqEJ33e ZHzujwu3oYWSyUtdA4EiDD6LVm16rdm9qnCmg1CzFBNToFcaqpFlK8hMEACd17ouGF/B SU8z3qM+54Gdqw99HxnTaRI9tB/ySISDte1LFF4JPsUKY4a1X5WStloOA6xFKGAGA0lm 9gyw== X-Gm-Message-State: APjAAAWSw5NpQNtK5F62Riy1fcnUoct5ZR+Q4GGTc9kxIrynvETVJqxm zJKZ/N9daGy6aDAThTV+A+Q= X-Google-Smtp-Source: APXvYqyjHBP6Ky2mspUst454rSxki3hW4y23rkcxYomBYUoZjYnk+QD/AlcwIriW+0mzpinwEfLa/w== X-Received: by 2002:a50:bb24:: with SMTP id y33mr14611589ede.116.1559348940661; Fri, 31 May 2019 17:29:00 -0700 (PDT) Received: from archlinux-epyc ([2a01:4f9:2b:2b15::2]) by smtp.gmail.com with ESMTPSA id h20sm1244729eja.37.2019.05.31.17.28.59 (version=TLS1_3 cipher=AEAD-AES256-GCM-SHA384 bits=256/256); Fri, 31 May 2019 17:29:00 -0700 (PDT) Date: Fri, 31 May 2019 17:28:58 -0700 From: Nathan Chancellor To: Arnd Bergmann Cc: Nick Desaulniers , Russell King , Nicolas Pitre , Stefan Agner , Linux ARM , Linux Kernel Mailing List , Ard Biesheuvel , clang-built-linux Subject: Re: [PATCH] ARM: xor-neon: Replace __GNUC__ checks with CONFIG_CC_IS_GCC Message-ID: <20190601002858.GA89184@archlinux-epyc> References: <20190528235742.105510-1-natechancellor@gmail.com> <20190531183227.GA34102@archlinux-epyc> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.12.0 (2019-05-25) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 31, 2019 at 11:03:19PM +0200, Arnd Bergmann wrote: > On Fri, May 31, 2019 at 10:06 PM 'Nick Desaulniers' via Clang Built > Linux wrote: > > > > On Fri, May 31, 2019 at 12:21 PM Arnd Bergmann wrote: > > > clang, I would suggest dropping your patch then, and instead adding > > > > I disagree. The minimum version of gcc required to build the kernel > > is 4.6, so the comment about older versions of gcc is irrelevant and > > should be removed. > > Sure, that's ok. It just feels wrong to remove a warning that points > to a real problem that still exists and can be detected at the moment. > > If we think that clang-9 is going to be fixed before its release, > the warning could be changed to test for that version as a minimum, > and point to the bugzilla entry for more details. > > Arnd I just tested the arm64 implementation and it shows the same warnings about cost as arm. However, I see a warning as something that can be resolved by the user. The GCC warning's solution is to just use a newer version of GCC (something fairly easily attainable). This new warning currently has no solution other than don't use clang. It is up to you and Nick but I would say unless we are going to prioritize fixing this, we shouldn't add a warning for it. I'd say it is more appropriate to fix it then add a warning saying upgrade to this version to fix it, like the GCC one (though I don't necessarily hate adding the warning assuming that clang 9 will have it fixed). Cheers, Nathan