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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,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 C4A90C43387 for ; Mon, 17 Dec 2018 21:03:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9B256217D9 for ; Mon, 17 Dec 2018 21:03:37 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389328AbeLQVDg (ORCPT ); Mon, 17 Dec 2018 16:03:36 -0500 Received: from mga12.intel.com ([192.55.52.136]:55417 "EHLO mga12.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388589AbeLQVDe (ORCPT ); Mon, 17 Dec 2018 16:03:34 -0500 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from fmsmga006.fm.intel.com ([10.253.24.20]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 17 Dec 2018 13:03:34 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.56,366,1539673200"; d="scan'208";a="302953560" Received: from tassilo.jf.intel.com (HELO tassilo.localdomain) ([10.7.201.137]) by fmsmga006.fm.intel.com with ESMTP; 17 Dec 2018 13:03:34 -0800 Received: by tassilo.localdomain (Postfix, from userid 1000) id 30335300B49; Mon, 17 Dec 2018 13:03:34 -0800 (PST) Date: Mon, 17 Dec 2018 13:03:34 -0800 From: Andi Kleen To: Josh Poimboeuf Cc: Arnd Bergmann , Peter Zijlstra , Linux Kernel Mailing List , the arch/x86 maintainers , Steven Rostedt , Miroslav Benes Subject: Re: objtool warnings for kernel/trace/trace_selftest_dynamic.o Message-ID: <20181217210334.GW25620@tassilo.jf.intel.com> References: <20181217173900.ygifx7khwmzn2gv2@treble> <20181217180434.GS25620@tassilo.jf.intel.com> <20181217181638.dfexg6mkmbfyzfli@treble> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20181217181638.dfexg6mkmbfyzfli@treble> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > That seems weird. > > > > Are you sure it's not just because they are empty? AFAIK > > gcc doesn't necessarily generate frame pointers for empty functions. > > I suspected that it was because they're empty, however I didn't see this > warning for other leaf functions. The sancov plugin is presumably > taking care of adding frame pointers where needed. Also, adding That would surprise me. > -mno-omit-leaf-frame-pointer didn't fix it. > > And anyway I confirmed that it was fixed by removing __noclone. So this is with a plugin? Maybe the plugin does something wrong? I thought this was just a standard build. I'm not sure the problem is well enough understood yet to really do anything. Do you have a simple standalone test case to show the compiler behavior? -Andi