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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 7110AC3A5A2 for ; Tue, 3 Sep 2019 19:33:35 +0000 (UTC) Received: from lists.ozlabs.org (lists.ozlabs.org [203.11.71.2]) (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 EEBBE217D7 for ; Tue, 3 Sep 2019 19:33:34 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org EEBBE217D7 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Received: from bilbo.ozlabs.org (lists.ozlabs.org [IPv6:2401:3900:2:1::3]) by lists.ozlabs.org (Postfix) with ESMTP id 46NHDr0TDWzDqlr for ; Wed, 4 Sep 2019 05:33:32 +1000 (AEST) Authentication-Results: lists.ozlabs.org; spf=permerror (mailfrom) smtp.mailfrom=kernel.crashing.org (client-ip=63.228.1.57; helo=gate.crashing.org; envelope-from=segher@kernel.crashing.org; receiver=) Authentication-Results: lists.ozlabs.org; dmarc=none (p=none dis=none) header.from=kernel.crashing.org Received: from gate.crashing.org (gate.crashing.org [63.228.1.57]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 46NHBj5kDBzDqlg for ; Wed, 4 Sep 2019 05:31:41 +1000 (AEST) Received: from gate.crashing.org (localhost.localdomain [127.0.0.1]) by gate.crashing.org (8.14.1/8.14.1) with ESMTP id x83JVTV8020900; Tue, 3 Sep 2019 14:31:29 -0500 Received: (from segher@localhost) by gate.crashing.org (8.14.1/8.14.1/Submit) id x83JVTPO020899; Tue, 3 Sep 2019 14:31:29 -0500 X-Authentication-Warning: gate.crashing.org: segher set sender to segher@kernel.crashing.org using -f Date: Tue, 3 Sep 2019 14:31:28 -0500 From: Segher Boessenkool To: Nathan Chancellor Subject: Re: [PATCH] powerpc: Avoid clang warnings around setjmp and longjmp Message-ID: <20190903193128.GC9749@gate.crashing.org> References: <20190812023214.107817-1-natechancellor@gmail.com> <878srdv206.fsf@mpe.ellerman.id.au> <20190828175322.GA121833@archlinux-threadripper> <20190828184529.GC127646@archlinux-threadripper> <6801a83ed6d54d95b87a41c57ef6e6b0@AcuMS.aculab.com> <20190903055553.GC60296@archlinux-threadripper> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190903055553.GC60296@archlinux-threadripper> User-Agent: Mutt/1.4.2.3i X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Nick Desaulniers , LKML , "# 3.4.x" , clang-built-linux , David Laight , Paul Mackerras , linuxppc-dev Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Mon, Sep 02, 2019 at 10:55:53PM -0700, Nathan Chancellor wrote: > On Thu, Aug 29, 2019 at 09:59:48AM +0000, David Laight wrote: > > From: Nathan Chancellor > > > Sent: 28 August 2019 19:45 > > ... > > > However, I think that -fno-builtin-* would be appropriate here because > > > we are providing our own setjmp implementation, meaning clang should not > > > be trying to do anything with the builtin implementation like building a > > > declaration for it. > > > > Isn't implementing setjmp impossible unless you tell the compiler that > > you function is 'setjmp-like' ? > > No idea, PowerPC is the only architecture that does such a thing. Since setjmp can return more than once, yes, exciting things can happen if you do not tell the compiler about this. Segher