From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gnu.wildebeest.org (wildebeest.demon.nl [212.238.236.112]) by sourceware.org (Postfix) with ESMTPS id C69553858D33 for ; Sun, 28 Feb 2021 15:22:48 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org C69553858D33 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=klomp.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=mark@klomp.org Received: from librem (deer0x15.wildebeest.org [172.31.17.151]) (using TLSv1.2 with cipher ADH-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by gnu.wildebeest.org (Postfix) with ESMTPSA id 05B8330006D6; Sun, 28 Feb 2021 16:22:46 +0100 (CET) Received: by librem (Postfix, from userid 1000) id 42165C0C5F; Sun, 28 Feb 2021 16:21:34 +0100 (CET) Date: Sun, 28 Feb 2021 16:21:34 +0100 From: Mark Wielaard To: Tom de Vries Cc: dwz@sourceware.org, jakub@redhat.com, nickc@redhat.com Subject: Re: [PATCH][testsuite] Handle readelf following links by default Message-ID: <20210228152134.GH3014@wildebeest.org> References: <20210228073647.GA25615@delia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210228073647.GA25615@delia> User-Agent: Mutt/1.10.1 (2018-07-13) X-Spam-Status: No, score=-5.3 required=5.0 tests=BAYES_00, JMQ_SPF_NEUTRAL, KAM_DMARC_STATUS, SPF_HELO_NONE, SPF_PASS, TXREP autolearn=no autolearn_force=no version=3.4.2 X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on server2.sourceware.org X-BeenThere: dwz@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Dwz mailing list List-Unsubscribe: , List-Archive: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 28 Feb 2021 15:22:51 -0000 Hi, Added Nick to the CC since he seems to have introduced this new "default". On Sun, Feb 28, 2021 at 08:36:49AM +0100, Tom de Vries wrote: > Since binutils commit c46b706620e "Change the readelf and objdump programs so > that they will automatically follow links to separate debug info files." there > are a few FAILs in the dwz testsuite. > > In the case of gnu-debugaltlink-name.sh, I think this is caused by a binutils > bug, filed as PR27478. > > In the case of odr-struct-multifile.sh, this is just due to flipping the > default. > > Fix/workaround this by testing whether the new -Wn readelf flag is supported, > and if so, adding it to the readelf call. > > Any comments? I think this is an odd bug in binutils. --debug-dump=follow-links seems to confuses two separate concepts. First whether or not to show data that might be stored in a "linked" file. Like whether to show a DW_FORM_GNU_alt_strp value. This seems fine and should indeed be done by default (that is also what eu-readelf does). Second whether to dump whole sections from the linked files. That is IMHO something completely different and causes the bug you filed. This second use should not be the default. And probably should be called something different, maybe --debug-dump=dump-links. Since this is luckily not yet in any released binutils lets fix this in binutils instead of trying to work around it in dwz. I am pretty sure it will break various other testsuites that rely on binutils readelf --debug-dump output if it suddenly also dumped sections from other files by default. Cheers, Mark