From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757962AbcAYVlj (ORCPT ); Mon, 25 Jan 2016 16:41:39 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:33000 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756184AbcAYVlh (ORCPT ); Mon, 25 Jan 2016 16:41:37 -0500 Date: Mon, 25 Jan 2016 13:41:36 -0800 From: Andrew Morton To: Andrey Ryabinin Cc: , , Subject: Re: [PATCH] ubsan: fix tree-wide -Wmaybe-uninitialized false positives Message-Id: <20160125134136.cee4919a8453c4753f177c3b@linux-foundation.org> In-Reply-To: <1453737694-19138-1-git-send-email-aryabinin@virtuozzo.com> References: <201601251528.rosikkYN%fengguang.wu@intel.com> <1453737694-19138-1-git-send-email-aryabinin@virtuozzo.com> X-Mailer: Sylpheed 3.4.1 (GTK+ 2.24.23; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 25 Jan 2016 19:01:34 +0300 Andrey Ryabinin wrote: > -fsanitize=* options makes GCC less smart than usual and increase number > of 'maybe-uninitialized' false-positives. So this patch does two things: > * Add -Wno-maybe-uninitialized to CFLAGS_UBSAN which will disable all > such warnings for instrumented files. > * Remove CONFIG_UBSAN_SANITIZE_ALL from all[yes|mod]config builds. So > the all[yes|mod]config build goes without -fsanitize=* and still with > -Wmaybe-uninitialized. hm, that's a bit sad. We have no means of working out whether we should re-enable maybe-uninitialized for later gcc's, as they become smarter about this. What do we do, just "remember" to try it later on? Do you know if this issue is on the gcc developer' radar?