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 C0A073857C77 for ; Sat, 13 Mar 2021 07:05:15 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org C0A073857C77 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-83-ySBm3ajsPby4BB0tCZfrBA-1; Sat, 13 Mar 2021 02:05:12 -0500 X-MC-Unique: ySBm3ajsPby4BB0tCZfrBA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 69BB78189C8; Sat, 13 Mar 2021 07:05:11 +0000 (UTC) Received: from oldenburg.str.redhat.com (ovpn-112-77.ams2.redhat.com [10.36.112.77]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 908C3614FF; Sat, 13 Mar 2021 07:05:10 +0000 (UTC) From: Florian Weimer To: Alessandro Carminati via Libc-help Cc: Alessandro Carminati Subject: Re: Fwd: MIPSEL GLIBC sem_init() not shared References: <87a6r87il4.fsf@oldenburg.str.redhat.com> <87sg505zy0.fsf@oldenburg.str.redhat.com> <87im5w4av2.fsf@oldenburg.str.redhat.com> Date: Sat, 13 Mar 2021 08:05:24 +0100 In-Reply-To: (Alessandro Carminati via Libc-help's message of "Sat, 13 Mar 2021 07:53:38 +0100") Message-ID: <87r1kjy1mz.fsf@oldenburg.str.redhat.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/27.1 (gnu/linux) MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-Spam-Status: No, score=-6.5 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_H3, RCVD_IN_MSPIKE_WL, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=ham 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-help@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Libc-help mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 13 Mar 2021 07:05:17 -0000 * Alessandro Carminati via Libc-help: > Reflecting on my scenario I see that the dynamic linker finds quite unusual > situation where the symbol is required and there's no dependency on the DSO > containing it, and no indication (.gnu.version_r) about how to handle it. > My assumption was that the double @@ would handle these situation, but it > is reasonable that this situation to have another handling. > For this reason my current understanding is that the dynamic linker would > use default the double @@ indicated function, where the .gnu.version_r is > present but not populated, and use the older symbol where > the .gnu.version_r is missing. This way it would handle correctly the > situation where old executables do not have the section because it didn't > exist yet. We could have done this for glibc itself perhaps, but it would break in the case of another shared object adding symbol versions after a release without symbols. Thanks, Florian