From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from gateway23.websitewelcome.com (gateway23.websitewelcome.com [192.185.49.104]) by sourceware.org (Postfix) with ESMTPS id A9B54383E835 for ; Fri, 22 May 2020 21:01:12 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org A9B54383E835 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=tromey.com Authentication-Results: sourceware.org; spf=fail smtp.mailfrom=tom@tromey.com Received: from cm16.websitewelcome.com (cm16.websitewelcome.com [100.42.49.19]) by gateway23.websitewelcome.com (Postfix) with ESMTP id 5CEFAC5A7 for ; Fri, 22 May 2020 16:01:12 -0500 (CDT) Received: from box5379.bluehost.com ([162.241.216.53]) by cmsmtp with SMTP id cEn2jjYax8vkBcEn2jOoFI; Fri, 22 May 2020 16:01:12 -0500 X-Authority-Reason: nr=8 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=tromey.com; s=default; h=Content-Type:MIME-Version:Message-ID:In-Reply-To:Date: References:Subject:Cc:To:From:Sender:Reply-To:Content-Transfer-Encoding: Content-ID:Content-Description:Resent-Date:Resent-From:Resent-Sender: Resent-To:Resent-Cc:Resent-Message-ID:List-Id:List-Help:List-Unsubscribe: List-Subscribe:List-Post:List-Owner:List-Archive; bh=8fTFws/FLUOXXqFEjipcIGqZrroMNHgwwfKT+9CvmcU=; b=FfR971SE3v+QiU2ojqomp8qEmA h3k8gYJAoyQ2fmhb+AujnM27zZjmfMOHCVg7wPTxc11ffm83l5gB+pMNwNU00NWTQ2KqSQu+ymB8m EvdsD0RPDvpDwh9UCi5frd0tI; Received: from 174-16-104-48.hlrn.qwest.net ([174.16.104.48]:36238 helo=murgatroyd) by box5379.bluehost.com with esmtpsa (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.92) (envelope-from ) id 1jcEn2-004Bon-3E; Fri, 22 May 2020 15:01:12 -0600 From: Tom Tromey To: Simon Marchi via Gdb-patches Cc: Simon Marchi Subject: Re: [PATCH v2 41/42] Make mapped_debug_names independent of objfile References: <20200512210913.5593-1-simon.marchi@efficios.com> <20200512211824.6834-42-simon.marchi@efficios.com> X-Attribution: Tom Date: Fri, 22 May 2020 15:01:11 -0600 In-Reply-To: <20200512211824.6834-42-simon.marchi@efficios.com> (Simon Marchi via Gdb-patches's message of "Tue, 12 May 2020 17:18:23 -0400") Message-ID: <87imgn1y7c.fsf@tromey.com> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/28.0.50 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-AntiAbuse: This header was added to track abuse, please include it with any abuse report X-AntiAbuse: Primary Hostname - box5379.bluehost.com X-AntiAbuse: Original Domain - sourceware.org X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12] X-AntiAbuse: Sender Address Domain - tromey.com X-BWhitelist: no X-Source-IP: 174.16.104.48 X-Source-L: No X-Exim-ID: 1jcEn2-004Bon-3E X-Source: X-Source-Args: X-Source-Dir: X-Source-Sender: 174-16-104-48.hlrn.qwest.net (murgatroyd) [174.16.104.48]:36238 X-Source-Auth: tom+tromey.com X-Email-Count: 1 X-Source-Cap: ZWx5bnJvYmk7ZWx5bnJvYmk7Ym94NTM3OS5ibHVlaG9zdC5jb20= X-Local-Domain: yes X-Spam-Status: No, score=-0.8 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, JMQ_SPF_NEUTRAL, RCVD_IN_BARRACUDACENTRAL, RCVD_IN_DNSWL_NONE, SPF_HELO_PASS, SPF_NEUTRAL, 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: gdb-patches@sourceware.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Gdb-patches mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 22 May 2020 21:01:14 -0000 >>>>> "Simon" == Simon Marchi via Gdb-patches writes: Simon> Ultimately, the objfile only seems to be needed because we might need to Simon> read a string from the string section. For that, we might need to read Simon> in the section, and if it's a relocatable section, the objfile is needed Simon> in order to do the relocation. This pattern happens often (that we to Simon> pass an objfile only because a section might be read). I think it's a Simon> bit ugly, but I don't have a good alternative right now. A long time ago, I changed the DWARF reader to read all the sections lazily. Off and on I've wondered whether that was actually a mistake. For one thing, it requires passing stuff like this around. Also, it can slow down hot paths, since they need to call the method to make sure the section is mapped. There's also at least one bug in bugzilla related to this (if you unlink a .so, gdb can be unhappy). For my threading project, I removed this lazy reading. We should consider doing this sooner, perhaps. The idea here is just that, if gdb is going to read the debuginfo anyway, then loading at least the sections needed to read .debug_info makes sense. Tom