From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 17608 invoked by alias); 10 Jun 2009 17:05:36 -0000 Received: (qmail 17584 invoked by uid 22791); 10 Jun 2009 17:05:31 -0000 X-SWARE-Spam-Status: No, hits=-2.4 required=5.0 tests=AWL,BAYES_00,SPF_PASS X-Spam-Check-By: sourceware.org Received: from mail.codesourcery.com (HELO mail.codesourcery.com) (65.74.133.4) by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Wed, 10 Jun 2009 17:05:20 +0000 Received: (qmail 22755 invoked from network); 10 Jun 2009 17:05:18 -0000 Received: from unknown (HELO orlando.local) (pedro@127.0.0.2) by mail.codesourcery.com with ESMTPA; 10 Jun 2009 17:05:18 -0000 From: Pedro Alves To: gdb-patches@sourceware.org, tromey@redhat.com Subject: Re: RFC: next/finish/etc -vs- exceptions Date: Wed, 10 Jun 2009 17:05:00 -0000 User-Agent: KMail/1.9.10 Cc: Joel Brobecker References: <20090610161204.GB25703@adacore.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Content-Disposition: inline Message-Id: <200906101806.31977.pedro@codesourcery.com> X-IsSubscribed: yes 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 X-SW-Source: 2009-06/txt/msg00264.txt.bz2 On Wednesday 10 June 2009 17:50:18, Tom Tromey wrote: > I was under the impression that Ada used longjmp to implement > exceptions, and so the existing longjmp support should work. =A0(Modulo > the odd bug or two -- I'm not sure if Pedro's fix for the glibc > pointer mangling went in or not.) It did not. Our longjmp support on glibc is still broken. I assume that exceptions have a property that raw longjmp doesn't, which is what makes stepping over longjmp complicated --- they never switch to alternate stacks? That was one reason why comparing frame/stack pointers with inner_than kind of comparisions is verboten (to know when the longjmp/exception is all inner to the step/next and can be ignored, for example). That, and frames crossing architectures, like on Cell. I did spot one such comparision by a quick look at the patch, but I don't know if it OK to do so in your case or not. I assume other people who know more about frames and unwinders than me can provide better input there. :-) --=20 Pedro Alves