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 [170.10.129.124]) by sourceware.org (Postfix) with ESMTPS id B69DF3858D33 for ; Mon, 2 May 2022 08:26:22 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.1 sourceware.org B69DF3858D33 Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-661-zKqy9C2NMZKjnMrHRmobqQ-1; Mon, 02 May 2022 04:26:21 -0400 X-MC-Unique: zKqy9C2NMZKjnMrHRmobqQ-1 Received: from smtp.corp.redhat.com (int-mx07.intmail.prod.int.rdu2.redhat.com [10.11.54.7]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id 1127B8015BA; Mon, 2 May 2022 08:26:21 +0000 (UTC) Received: from oldenburg.str.redhat.com (unknown [10.39.192.59]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 3F69F14C26A2; Mon, 2 May 2022 08:26:20 +0000 (UTC) From: Florian Weimer To: Fangrui Song Cc: Fangrui Song via Libc-alpha Subject: Re: [PATCH] elf: Remove fallback to the start of DT_STRTAB for dladdr References: <20220501215049.2143788-1-maskray@google.com> <87sfps8lt6.fsf@oldenburg.str.redhat.com> <20220502070415.kv62bjtdhhcyefjn@google.com> <87k0b48kmw.fsf@oldenburg.str.redhat.com> <20220502073034.tnhl25h43me2oggu@google.com> Date: Mon, 02 May 2022 10:26:18 +0200 In-Reply-To: <20220502073034.tnhl25h43me2oggu@google.com> (Fangrui Song's message of "Mon, 2 May 2022 00:30:34 -0700") Message-ID: <87fsls8hn9.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 2.85 on 10.11.54.7 X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain X-Spam-Status: No, score=-5.1 required=5.0 tests=BAYES_00, DKIMWL_WL_HIGH, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, RCVD_IN_DNSWL_LOW, SPF_HELO_NONE, SPF_NONE, TXREP, T_SCC_BODY_TEXT_LINE 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: Mon, 02 May 2022 08:26:24 -0000 * Fangrui Song: > If we argue that DT_HASH is mandatory, then --hash-style=gnu breaks the ELF > specification as well. For the GNU ABI, one of them must be available for dynamic linking. > My point is that a normal dynamic linking object always has either > .hash or .gnu.hash . If neither is present, it seems pretty fair for > dladdr to not give a symbol, just like symbol search (including > relocation resolving and dl(v)sym) won't give any result. Okay, let me have another look at the patch then. Thanks, Florian