From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 32214 invoked by alias); 17 Feb 2016 15:32:11 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Received: (qmail 32197 invoked by uid 89); 17 Feb 2016 15:32:10 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=BAYES_00,RP_MATCHES_RCVD,SPF_HELO_PASS autolearn=ham version=3.3.2 spammy=Hx-languages-length:1191, Want X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with (AES256-GCM-SHA384 encrypted) ESMTPS; Wed, 17 Feb 2016 15:32:09 +0000 Received: from int-mx09.intmail.prod.int.phx2.redhat.com (int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22]) by mx1.redhat.com (Postfix) with ESMTPS id 520E02DC372; Wed, 17 Feb 2016 15:32:08 +0000 (UTC) Received: from [127.0.0.1] (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1]) by int-mx09.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id u1HFW6XF003083; Wed, 17 Feb 2016 10:32:07 -0500 Message-ID: <56C49276.8080601@redhat.com> Date: Wed, 17 Feb 2016 15:32:00 -0000 From: Pedro Alves User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: "Metzger, Markus T" , Joel Brobecker CC: "gdb-patches@sourceware.org" Subject: Re: [PATCH v2 2/3] frame: use get_prev_frame_always in skip_tailcall_frames References: <1454681922-2228-1-git-send-email-markus.t.metzger@intel.com> <1454681922-2228-2-git-send-email-markus.t.metzger@intel.com> <20160207130057.GE20874@adacore.com> <56B9D08F.6060507@redhat.com> <20160209115819.GH15342@adacore.com> <56B9FA90.5030602@redhat.com> In-Reply-To: Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-SW-Source: 2016-02/txt/msg00512.txt.bz2 On 02/15/2016 09:50 AM, Metzger, Markus T wrote: > I'm wondering in which cases GDB should ignore the user-defined backtrace > limit. And if GDB should ignore it at all. > > If the limit is set, some aspects of GDB may not function any longer. But that's > to be expected, isn't it? > > GDB shouldn't crash, of course. But I'm not sure if it should ignore user settings > in too many cases. I'm starting to think the same way. Want to give it a try and see what breaks? > Maybe we should even switch back to get_prev_frame in > skip_artificial_frames and rely on handling the NULL return if we exceed the > backtrace limit? If all places will end up throwing an error, it may be the better to make skip_artificial_frames itself throw. We'd have to take a deeper look at each case though. We need to also keep in mind that there may be cases where skip_artificial_frames might be used in internal-facing code, where it might still be necessary get past inline frames to reach the real stack frame. I guess sticking a "set backtrace limit 1" in some of the inline tests would expose this. Thanks, Pedro Alves