From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 13617 invoked by alias); 1 Oct 2012 18:54:45 -0000 Received: (qmail 13608 invoked by uid 22791); 1 Oct 2012 18:54:44 -0000 X-SWARE-Spam-Status: No, hits=-7.4 required=5.0 tests=AWL,BAYES_00,KHOP_RCVD_UNTRUST,RCVD_IN_DNSWL_HI,RCVD_IN_HOSTKARMA_W,RP_MATCHES_RCVD,SPF_HELO_PASS X-Spam-Check-By: sourceware.org Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 01 Oct 2012 18:54:33 +0000 Received: from int-mx12.intmail.prod.int.phx2.redhat.com (int-mx12.intmail.prod.int.phx2.redhat.com [10.5.11.25]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id q91IsV2A009811 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK); Mon, 1 Oct 2012 14:54:31 -0400 Received: from host2.jankratochvil.net (ovpn-116-34.ams2.redhat.com [10.36.116.34]) by int-mx12.intmail.prod.int.phx2.redhat.com (8.14.4/8.14.4) with ESMTP id q91Irspk024826 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NO); Mon, 1 Oct 2012 14:53:57 -0400 Date: Mon, 01 Oct 2012 18:54:00 -0000 From: Jan Kratochvil To: Joshua Watt Cc: Joel Brobecker , gdb@sourceware.org Subject: Re: Option to disable frame checking Message-ID: <20121001185353.GA6119@host2.jankratochvil.net> References: <20121001172117.GG30746@adacore.com> <20121001172618.GA23158@host2.jankratochvil.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-IsSubscribed: yes Mailing-List: contact gdb-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-owner@sourceware.org X-SW-Source: 2012-10/txt/msg00015.txt.bz2 On Mon, 01 Oct 2012 20:38:54 +0200, Joshua Watt wrote: > I'm not sure how that would be accomplished. AFAIK, there isn't any sort of > information in the DWARF debugging format that could be used to (definitively) > indicate the thread has jumped stacks, so I think it would have to be determined > by something external to the code being debugged. I think that such a heuristic > approach could be difficult to get correct in all cases, In such case the "alternate stack" feature is insufficiently designed and it should be extended for its debuggability. Debuggability is a normal associated part of any new ABI feature. > hence the idea of making it a user configurable option. Every user configurable option is just a last resort workaround. In the best world there would be no configuration options, ever. > I won't claim to be an expert in the DWARF debugging format though, It does not always have to be in DWARF. For example the gcc -fsplit-stack did not need any DWARF extensions (it was enough to verify specific ELF symbol). http://sourceware.org/git/?p=gdb.git;a=commitdiff;h=457da755a718113dcbc339f7823af0d439fa62c7 Thanks, Jan