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=-6.1 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=unavailable 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 7ABCCC433E0 for ; Fri, 3 Jul 2020 13:25:50 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id CB1C920760 for ; Fri, 3 Jul 2020 13:25:49 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="zDmqGVF3" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org CB1C920760 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=infradead.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19207-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 26539 invoked by uid 550); 3 Jul 2020 13:25:42 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 26501 invoked from network); 3 Jul 2020 13:25:42 -0000 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==; 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> 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.