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=-5.8 required=3.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS 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 92028C433E0 for ; Fri, 3 Jul 2020 13:25:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 541DE20760 for ; Fri, 3 Jul 2020 13:25:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="zDmqGVF3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726318AbgGCNZe (ORCPT ); Fri, 3 Jul 2020 09:25:34 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33270 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726022AbgGCNZe (ORCPT ); Fri, 3 Jul 2020 09:25:34 -0400 Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:8b0:10b:1231::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id BACF4C08C5C1; Fri, 3 Jul 2020 06:25:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=merlin.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=mTUdInrl0UZ5/CAUTtR8K6FDHzAHWr9fq3pJX4MJ7Gs=; b=zDmqGVF3FOX7aSDK4H8sAB/UGf KrxUneT0wbec5AHPOWFWgsQ58J7O+x9kLSh6PJJns7NSEVQU5N9HLWo16vbkLGQakk7aa0dWh7QcL grhzH9Vhd13yLmAKDlzxBAGgMJUMhc2N63hyENk4ip1OBwF3lMnThKgxhGjHOf93UVGDhIJabxxdh PUNVs3yxqSKjZQoFoCbxqN8YldUcpszlAWVdmsX979wqXUgCBvBmOoPH/nHcee/NLh6hdRgtBFf9u OxuXx54Xhpa+MCreoZf20laWaE2S6iSRhTAi9+Q78S4yOV4Vk9Mo0GC1/n+tL0uvPfxff2DnoUFjs DrqF4xAQ==; Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jrLgy-0002iy-Rt; Fri, 03 Jul 2020 13:25:25 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 718DD301124; Fri, 3 Jul 2020 15:25:23 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 5F59B20A9E7A6; Fri, 3 Jul 2020 15:25:23 +0200 (CEST) Date: Fri, 3 Jul 2020 15:25:23 +0200 From: Peter Zijlstra To: "Paul E. McKenney" Cc: Marco Elver , Nick Desaulniers , Sami Tolvanen , Masahiro Yamada , Will Deacon , Greg Kroah-Hartman , Kees Cook , clang-built-linux , Kernel Hardening , linux-arch , Linux ARM , Linux Kbuild mailing list , LKML , linux-pci@vger.kernel.org, "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" Subject: Re: [PATCH 00/22] add support for Clang LTO Message-ID: <20200703132523.GM117543@hirez.programming.kicks-ass.net> References: <20200630201243.GD4817@hirez.programming.kicks-ass.net> <20200630203016.GI9247@paulmck-ThinkPad-P72> <20200701114027.GO4800@hirez.programming.kicks-ass.net> <20200701140654.GL9247@paulmck-ThinkPad-P72> <20200701150512.GH4817@hirez.programming.kicks-ass.net> <20200701160338.GN9247@paulmck-ThinkPad-P72> <20200702082040.GB4781@hirez.programming.kicks-ass.net> <20200702175948.GV9247@paulmck-ThinkPad-P72> <20200703131330.GX4800@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200703131330.GX4800@hirez.programming.kicks-ass.net> Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Jul 03, 2020 at 03:13:30PM +0200, Peter Zijlstra wrote: > > The prototype for GCC is here: https://github.com/AKG001/gcc/ > > Thanks! Those test cases are somewhat over qualified though: > > static volatile _Atomic (TYPE) * _Dependent_ptr a; \ One question though; since its a qualifier, and we've recently spend a whole lot of effort to strip qualifiers in say READ_ONCE(), how does, and how do we want, this qualifier to behave. C++ has very convenient means of manipulating qualifiers, so it's not much of a problem there, but for C it is, as we've found, really quite cumbersome. Even with _Generic() we can't manipulate individual qualifiers afaict. 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=-6.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,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 F035AC433DF for ; Fri, 3 Jul 2020 13:26:46 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (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 BCE9720760 for ; Fri, 3 Jul 2020 13:26:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="w/o3qa0b" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org BCE9720760 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.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=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References:Message-ID: Subject:To:From:Date:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=BZFo7QBh/hPvThYOcpd9v3hP8MWwAqYeMfEPAtPX168=; b=w/o3qa0brpHyFndsAq8tuM5GH JSlisWx0hZgCpzSU8yDT2a43ISbCjpn2FSx283A5WJzSzPOr05opDaxFXm8x6pcGNni3WH1lVkGxE y3fuphvMhIcpACVhpa0ZKJ0EB+Gfz94RTyAjZwgSbAR1FmB+cQLrVfSkGnFRpRfV6todOK3W/Fapo PCG9c5Q0apYYEIYQ6hYwNQA4emNmCzXTuvRQNLqJe4oHAAb/nBbp1JxopIozgYhSFX8pOpVH38eBB lTgqG+CJY3rOHW6ARP5393NxoAtLKQmgA6UTiVnHbZQ6TPq+6ZWWchOU97V+lSFRqXfQxUr5zWMKO 4djBZiWVg==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jrLh2-0002kC-QS; Fri, 03 Jul 2020 13:25:28 +0000 Received: from j217100.upc-j.chello.nl ([24.132.217.100] helo=noisy.programming.kicks-ass.net) by merlin.infradead.org with esmtpsa (Exim 4.92.3 #3 (Red Hat Linux)) id 1jrLgy-0002iy-Rt; Fri, 03 Jul 2020 13:25:25 +0000 Received: from hirez.programming.kicks-ass.net (hirez.programming.kicks-ass.net [192.168.1.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by noisy.programming.kicks-ass.net (Postfix) with ESMTPS id 718DD301124; Fri, 3 Jul 2020 15:25:23 +0200 (CEST) Received: by hirez.programming.kicks-ass.net (Postfix, from userid 1000) id 5F59B20A9E7A6; Fri, 3 Jul 2020 15:25:23 +0200 (CEST) Date: Fri, 3 Jul 2020 15:25:23 +0200 From: Peter Zijlstra To: "Paul E. McKenney" Subject: Re: [PATCH 00/22] add support for Clang LTO Message-ID: <20200703132523.GM117543@hirez.programming.kicks-ass.net> References: <20200630201243.GD4817@hirez.programming.kicks-ass.net> <20200630203016.GI9247@paulmck-ThinkPad-P72> <20200701114027.GO4800@hirez.programming.kicks-ass.net> <20200701140654.GL9247@paulmck-ThinkPad-P72> <20200701150512.GH4817@hirez.programming.kicks-ass.net> <20200701160338.GN9247@paulmck-ThinkPad-P72> <20200702082040.GB4781@hirez.programming.kicks-ass.net> <20200702175948.GV9247@paulmck-ThinkPad-P72> <20200703131330.GX4800@hirez.programming.kicks-ass.net> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20200703131330.GX4800@hirez.programming.kicks-ass.net> X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch , Marco Elver , "maintainer:X86 ARCHITECTURE \(32-BIT AND 64-BIT\)" , Kees Cook , Kernel Hardening , Greg Kroah-Hartman , Masahiro Yamada , Linux Kbuild mailing list , Nick Desaulniers , LKML , clang-built-linux , Sami Tolvanen , linux-pci@vger.kernel.org, Will Deacon , Linux ARM 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 Fri, Jul 03, 2020 at 03:13:30PM +0200, Peter Zijlstra wrote: > > The prototype for GCC is here: https://github.com/AKG001/gcc/ > > Thanks! Those test cases are somewhat over qualified though: > > static volatile _Atomic (TYPE) * _Dependent_ptr a; \ One question though; since its a qualifier, and we've recently spend a whole lot of effort to strip qualifiers in say READ_ONCE(), how does, and how do we want, this qualifier to behave. C++ has very convenient means of manipulating qualifiers, so it's not much of a problem there, but for C it is, as we've found, really quite cumbersome. Even with _Generic() we can't manipulate individual qualifiers afaict. _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel