From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 33950 invoked by alias); 9 Feb 2018 18:37:18 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 33924 invoked by uid 89); 9 Feb 2018 18:37:18 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-2.3 required=5.0 tests=AWL,BAYES_00,KAM_LAZY_DOMAIN_SECURITY,RCVD_IN_DNSWL_LOW,T_RP_MATCHES_RCVD autolearn=no version=3.3.2 spammy= X-HELO: mx1.redhat.com Received: from mx3-rdu2.redhat.com (HELO mx1.redhat.com) (66.187.233.73) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Fri, 09 Feb 2018 18:37:17 +0000 Received: from smtp.corp.redhat.com (int-mx06.intmail.prod.int.rdu2.redhat.com [10.11.54.6]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C3B8B401DE92 for ; Fri, 9 Feb 2018 18:37:15 +0000 (UTC) Received: from tucnak.zalov.cz (ovpn-116-56.ams2.redhat.com [10.36.116.56]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E8F532166BAE for ; Fri, 9 Feb 2018 18:37:06 +0000 (UTC) Received: from tucnak.zalov.cz (localhost [127.0.0.1]) by tucnak.zalov.cz (8.15.2/8.15.2) with ESMTP id w19I7lrA032033; Fri, 9 Feb 2018 19:07:48 +0100 Received: (from jakub@localhost) by tucnak.zalov.cz (8.15.2/8.15.2/Submit) id w19I7jTi032032; Fri, 9 Feb 2018 19:07:45 +0100 Date: Fri, 09 Feb 2018 18:37:00 -0000 From: Jakub Jelinek To: Richard Biener Cc: Paolo Bonzini , gcc-patches@gcc.gnu.org, marcandre.lureau@redhat.com, mliska@suse.cz Subject: Re: [PATCH] Improve dead code elimination with -fsanitize=address (PR84307) Message-ID: <20180209180745.GK5867@tucnak> Reply-To: Jakub Jelinek References: <1518192504-49084-1-git-send-email-bonzini@gnu.org> <2bd36577-88f0-2926-d777-ee9a11d315f4@gnu.org> <4FD5AE20-78E2-4741-A6CB-EA2B0AA3514F@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4FD5AE20-78E2-4741-A6CB-EA2B0AA3514F@gmail.com> User-Agent: Mutt/1.9.1 (2017-09-22) X-IsSubscribed: yes X-SW-Source: 2018-02/txt/msg00543.txt.bz2 On Fri, Feb 09, 2018 at 07:01:08PM +0100, Richard Biener wrote: > >which indeed fixes the testcase and seems not to break asan.exp. > > Huh. Need to double check why that makes sense ;) I think it does, for both ASAN_CHECK and ASAN_MARK the pointer argument is the second one, the first one is an integer argument with flags. And ASAN_MARK, both poison and unpoison, works kind like a clobber on the referenced variable, before unpoison it is generally inaccessible and after poison too. Jakub