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 BD4373844031 for ; Thu, 22 Apr 2021 15:38:55 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org BD4373844031 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-315-5Px9eEEIOrS2sPLBSRzKkQ-1; Thu, 22 Apr 2021 11:38:50 -0400 X-MC-Unique: 5Px9eEEIOrS2sPLBSRzKkQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.phx2.redhat.com [10.5.11.22]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 364AA343AB; Thu, 22 Apr 2021 15:38:49 +0000 (UTC) Received: from oldenburg.str.redhat.com (ovpn-113-20.ams2.redhat.com [10.36.113.20]) by smtp.corp.redhat.com (Postfix) with ESMTPS id E974F100760B; Thu, 22 Apr 2021 15:38:47 +0000 (UTC) From: Florian Weimer To: Szabolcs Nagy Cc: Pedro Alves , Florian Weimer via Libc-alpha , gdb-patches@sourceware.org Subject: Re: [PATCH v3] nptl_db: Support different libpthread/ld.so load orders (bug 27744) References: <87tuo24kxi.fsf@oldenburg.str.redhat.com> <87czunoo5m.fsf@oldenburg.str.redhat.com> <20210422072821.GE9028@arm.com> <87o8e6k9br.fsf@oldenburg.str.redhat.com> <20210422090501.GH9028@arm.com> <20210422094808.GJ9028@arm.com> <87pmymildh.fsf@oldenburg.str.redhat.com> <20210422124455.GK9028@arm.com> <20210422142030.GL9028@arm.com> <87pmymgzuy.fsf@oldenburg.str.redhat.com> <20210422153008.GM9028@arm.com> Date: Thu, 22 Apr 2021 17:39:05 +0200 In-Reply-To: <20210422153008.GM9028@arm.com> (Szabolcs Nagy's message of "Thu, 22 Apr 2021 16:30:10 +0100") Message-ID: <87a6pqgwh2.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 2.84 on 10.5.11.22 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: quoted-printable X-Spam-Status: No, score=-6.4 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_PASS, TXREP autolearn=unavailable autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) 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: Thu, 22 Apr 2021 15:38:56 -0000 * Szabolcs Nagy: >> Would you please check if the issue goes away if you replace >>=20 >> "add-symbol-file %1$s/nptl/tst-pthread-gdb-attach\n" >>=20 >> with >> "file %1$s/nptl/tst-pthread-gdb-attach\n" >>=20 >> ? >>=20 >> (I assume this happens without --enable-hardcoded-path-in-tests.) > > yes, it seems gdb does not work with > > ld.so ./exe > > if exe is pie. i could not get it to work wit file either. > > add-symbol-file fails even without ld.so, just pie exe fails. But =E2=80=9Cfile=E2=80=9D works? > you have to use -o offset argument to add-symbol-file and > manually fish out the base offset from info proc map, i don't > think that can be easily scripted. Oh, it's essentially a self-attach (after fork), so we can just read the base address from the running process. If there's an easy way to do that. In theory, it's just looking at a symbol at the main program and subtracting its virtual offset, but I don't know how to get that. Thanks, Florian