From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from simark.ca (simark.ca [158.69.221.121]) by sourceware.org (Postfix) with ESMTPS id F35C7383F851 for ; Mon, 15 Jun 2020 14:58:08 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.3.2 sourceware.org F35C7383F851 Authentication-Results: sourceware.org; dmarc=none (p=none dis=none) header.from=simark.ca Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=simark@simark.ca Received: from [172.16.0.95] (192-222-181-218.qc.cable.ebox.net [192.222.181.218]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by simark.ca (Postfix) with ESMTPSA id 4E9051E5F9; Mon, 15 Jun 2020 10:58:07 -0400 (EDT) Subject: Re: [PATCH] Fixing get_builder() function in dwarf2/read.c To: watashiwaher , gdb-patches@sourceware.org References: From: Simon Marchi Message-ID: <95d33ff4-2215-d9f1-2093-2f75bb48cd99@simark.ca> Date: Mon, 15 Jun 2020 10:58:06 -0400 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.8.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: tl Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-8.5 required=5.0 tests=BAYES_00, KAM_DMARC_STATUS, SPF_HELO_PASS, 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: 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: Mon, 15 Jun 2020 14:58:10 -0000 On 2020-06-14 1:07 p.m., watashiwaher wrote: > It is a shame. But it seems I can't. Also I am not so strong in dwarf2. > The binary was so huge and so private, that I was so dumb to understand what actually inside binary got wrong :( > All I just noticed, it is that get_builder() calls itself recursively, in such manner: > ptr1 -> ptr2 -> ptr1 -> ptr2 -> ... > And tho I made a small patch that: > 1) eliminate recursion > 2) uses tortoise algorithm to break out of loop > All I can say, that I really had a halt in this function due to the recursion, because I debugged that halt in GDB... Could you at least provide a backtrace of GDB in this endless loop? Then we can maybe understand what got it that way and build a reproducer from that. Simon