From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [216.205.24.124]) by sourceware.org (Postfix) with ESMTP id ECE2C3951858 for ; Wed, 21 Jul 2021 13:07:49 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org ECE2C3951858 Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-459-hIL72OyxONedNp9YJL_XIQ-1; Wed, 21 Jul 2021 09:07:46 -0400 X-MC-Unique: hIL72OyxONedNp9YJL_XIQ-1 Received: from smtp.corp.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 26538107394E; Wed, 21 Jul 2021 13:06:28 +0000 (UTC) Received: from oldenburg.str.redhat.com (ovpn-113-201.ams2.redhat.com [10.36.113.201]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 4DEE36E0B8; Wed, 21 Jul 2021 13:06:27 +0000 (UTC) From: Florian Weimer To: Martin Sebor via Libc-alpha Subject: Re: [RFC patch] avoid warning on accesses to hardwired address References: <59b05c40-d0a8-233a-27c5-104b24bdc9b4@gmail.com> <87sg0oj8q7.fsf@oldenburg.str.redhat.com> Date: Wed, 21 Jul 2021 15:06:25 +0200 In-Reply-To: <87sg0oj8q7.fsf@oldenburg.str.redhat.com> (Florian Weimer's message of "Fri, 09 Jul 2021 08:34:56 +0200") Message-ID: <87lf5zn7e6.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.2 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.11 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-Spam-Status: No, score=-7.3 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H4, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_NONE, TXREP autolearn=ham autolearn_force=no version=3.4.4 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 21 Jul 2021 13:07:51 -0000 * Florian Weimer: > * Martin Sebor via Libc-alpha: > >> Thanks to recent code refactoring in GCC 12, -Warray-bounds has >> started to diagnose accesses to constant addresses just like many >> other flow based warnings do (e.g., -Wstringop-overflow). >> The warnings are meant to help detect accesses resulting from >> invalid arithmetic on null pointers. There may be a better way >> to detect them but GCC doesn't have the detection yet. This >> warning change has in turn exposed Glibc's uses of this trick >> in the implementation of the THREAD_SELF macro. > > The warning needs to be disabled in GCC for named address spaces. Null > pointers are not special for them. Is there already a GCC PR for this warning regression? Thanks, Florian