From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 1896 invoked by alias); 20 May 2011 19:26:10 -0000 Received: (qmail 1882 invoked by uid 22791); 20 May 2011 19:26:09 -0000 X-SWARE-Spam-Status: No, hits=-6.9 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_HI,SPF_HELO_PASS,T_RP_MATCHES_RCVD 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; Fri, 20 May 2011 19:25:51 +0000 Received: from int-mx01.intmail.prod.int.phx2.redhat.com (int-mx01.intmail.prod.int.phx2.redhat.com [10.5.11.11]) by mx1.redhat.com (8.14.4/8.14.4) with ESMTP id p4KJPpSm024338 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK) for ; Fri, 20 May 2011 15:25:51 -0400 Received: from ns3.rdu.redhat.com (ns3.rdu.redhat.com [10.11.255.199]) by int-mx01.intmail.prod.int.phx2.redhat.com (8.13.8/8.13.8) with ESMTP id p4KJPoJk002013; Fri, 20 May 2011 15:25:51 -0400 Received: from opsy.redhat.com (ovpn01.gateway.prod.ext.phx2.redhat.com [10.5.9.1]) by ns3.rdu.redhat.com (8.13.8/8.13.8) with ESMTP id p4KJPoxe009805; Fri, 20 May 2011 15:25:50 -0400 Received: by opsy.redhat.com (Postfix, from userid 500) id EC751378D08; Fri, 20 May 2011 13:25:49 -0600 (MDT) From: Tom Tromey To: Keith Seitz Cc: gdb-patches@sourceware.org Subject: Re: The future of dwarf2_physname References: <4DD44983.7060406@redhat.com> <20110519205943.GA7479@caradoc.them.org> Date: Fri, 20 May 2011 19:26:00 -0000 In-Reply-To: <20110519205943.GA7479@caradoc.them.org> (Daniel Jacobowitz's message of "Thu, 19 May 2011 16:59:43 -0400") Message-ID: User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/23.2 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii 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: 2011-05/txt/msg00498.txt.bz2 >>>>> "Daniel" == Daniel Jacobowitz writes: Daniel> In general, the sort of cross-check Jan has implemented could never Daniel> reliably pass without extensions to DWARF. Once you get up into Daniel> templates, especially, there are template arguments that are hard Daniel> or impossible to represent in template parameter DIEs. DWARF 4 added some stuff to help with this, but I think g++ hasn't yet caught up. What problems do you know about? I know of this: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=41736 ... namely, that g++ doesn't emit a value for a pointer-to-member template parameter. But this is a g++ bug, not a DWARF omission. Also there is: http://gcc.gnu.org/bugzilla/show_bug.cgi?id=33861 I don't think I totally understand the issues with this one, but the DWARF just has an address, so presumably in some scenarios we can wind up with an odd canonical name (if we can't find the name corresponding to that address). It seems to me that if the DWARF spec is incomplete, then that is an argument in favor of either (1) fixing DWARF and g++ or (2) keeping DW_AT_linkage_name in g++ -- but not just dropping linkage-name, as that would cause user-visible regressions. Tom