From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp.codeaurora.org by pdx-caf-mail.web.codeaurora.org (Dovecot) with LMTP id jDazATqFGVv1MgAAmS7hNA ; Thu, 07 Jun 2018 19:23:49 +0000 Received: by smtp.codeaurora.org (Postfix, from userid 1000) id C8E3D6074D; Thu, 7 Jun 2018 19:23:48 +0000 (UTC) Authentication-Results: smtp.codeaurora.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="tgzLe+C6" X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on pdx-caf-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.5 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,T_DKIMWL_WL_MED, USER_IN_DEF_DKIM_WL autolearn=ham autolearn_force=no version=3.4.0 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by smtp.codeaurora.org (Postfix) with ESMTP id 2CAD86063F; Thu, 7 Jun 2018 19:23:48 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 smtp.codeaurora.org 2CAD86063F Authentication-Results: pdx-caf-mail.web.codeaurora.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: pdx-caf-mail.web.codeaurora.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753028AbeFGTXp (ORCPT + 25 others); Thu, 7 Jun 2018 15:23:45 -0400 Received: from mail-pl0-f68.google.com ([209.85.160.68]:42648 "EHLO mail-pl0-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750903AbeFGTXo (ORCPT ); Thu, 7 Jun 2018 15:23:44 -0400 Received: by mail-pl0-f68.google.com with SMTP id w17-v6so6741177pll.9 for ; Thu, 07 Jun 2018 12:23:44 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=LKUq8EW8/jGY7z4VbTzriOkFRTwtP1HW5von+rEJnbE=; b=tgzLe+C60bZKyDRSzJp6c70lf/zHcgrDdI9FyvfHJflX69RUOqRzDx52Fnz2IjNQyN eE0F2toxcPOWVdg0A0KvDVaWN/qzSX97DFmerHwtzibe0bTm5EkOB5KN6EB+8DUb7lbO 9lUl/YPUfxx5VGCchyHFvKbVBdtsOknqgIMfqXF2/IwZOM4LZECeJytsWcixE/leH6Ir k8BYn2MD27TrGNFMFqS2Ip5VqkeKpaifJU7J+CYOipynwkr6d/PKexvZK8gVLl7EihLk cMzM/JYfq1Nc92IE/ElilQooam8C/LuLt7TTY2a9iWi1D7ARuKRi6nEjVG/0AjZFcHUr VGrw== 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=LKUq8EW8/jGY7z4VbTzriOkFRTwtP1HW5von+rEJnbE=; b=a0sXC55E0jtjWTekrIiYfP2gKfTNGJ+k0dB1OcyNvLn0g2U4HaAVkL23UYVc2jwjPJ PuKgvaTdGfuCLNK1+jUJhu3IELMonpRAwhN8+G9OApZIVqG/YUEuRxfCW9mNcRMekjoB L+UIZ0ui0K9JtQzZGWW5idV+i/mVWTX/6SNXFdAXcki54VYossxnJhj0GgAlBPh9q2QJ D/ZBB7YAuF1pF+Kvc67AkK4CFB/eEo3D2tFubIdNIbAimRAlVJ8BfhtDI9zoHodRVV4q NldSnx/FrlYuiCONFhDe3k5ufKSTFfPFe96ZMkRvK6nJYuKq9ljoPw7LzHzIIArqzJCl iRRQ== X-Gm-Message-State: APt69E1eDvBkm33stw4E/3jhZmmzRL42r0NBTYNKHspgn1rTdJlUVO5f xH/yGie4JxlMTSS0JGPlk7CjDCWdm3Z+MWm6vNeCmQ== X-Google-Smtp-Source: ADUXVKJGFNBiP6tjPayeWnjNgZKgqmw3GdobCysYRpvQkl21MaAlI0f+8YcO1qR2Yoy+2LpWoNQ1pKEmq/sohTrkNTI= X-Received: by 2002:a17:902:5409:: with SMTP id d9-v6mr3381543pli.0.1528399423292; Thu, 07 Jun 2018 12:23:43 -0700 (PDT) MIME-Version: 1.0 References: <20180402095033.nfzcrmxvpm46dhbl@gmail.com> <20180403085904.GY4082@hirez.programming.kicks-ass.net> <20180403095118.rpf7tj577dppvx7d@gmail.com> <20180403180658.GE87376@google.com> <20180404093823.GC25996@kroah.com> <20180404193247.lsoxe3xjcidwtlgv@treble> In-Reply-To: <20180404193247.lsoxe3xjcidwtlgv@treble> From: Nick Desaulniers Date: Thu, 7 Jun 2018 12:23:31 -0700 Message-ID: Subject: Re: [GIT PULL] x86/build changes for v4.17 To: Josh Poimboeuf Cc: Greg KH , Matthias Kaehlcke , Ingo Molnar , Peter Zijlstra , Linus Torvalds , LKML , Thomas Gleixner , Andrew Morton , James Y Knight , Chandler Carruth , Stephen Hines , Kees Cook , groeck@chromium.org, Greg Hackmann Content-Type: text/plain; charset="UTF-8" Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Apr 4, 2018 at 12:32 PM Josh Poimboeuf wrote: > > On Wed, Apr 04, 2018 at 04:53:52PM +0000, Nick Desaulniers wrote: > > (re-sending as plain text) > > > > On Wed, Apr 4, 2018 at 2:38 AM Greg KH wrote: > > > There are known-bugs with building a kernel with clang right now (I > > > pointed one out a few days ago about NULL checks being deleted from the > > > clang output for no good reason, which really is scary for obvious > > > reasons). > > > > Is this the thread you are referring to? > > https://lkml.org/lkml/2018/3/27/1286 > > > > It's definitely something curious that I'll need to sit down and > > investigate more. If there are other known instances, it would be good to > > let me know. > > As Matthias mentioned elsewhere, it sounds like they're planning to > implement -fno-delete-null-pointer-checks, which would presumably fix > the above issue. Just to follow this up, -fno-delete-null-pointer-checks is being added to clang in: https://reviews.llvm.org/D47894 https://reviews.llvm.org/D47895 -- Thanks, ~Nick Desaulniers