From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 8918 invoked by alias); 5 May 2003 14:08:26 -0000 Mailing-List: contact gdb-patches-help@sources.redhat.com; run by ezmlm Precedence: bulk List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sources.redhat.com Received: (qmail 8907 invoked from network); 5 May 2003 14:08:25 -0000 Received: from unknown (HELO localhost.redhat.com) (207.219.125.105) by sources.redhat.com with SMTP; 5 May 2003 14:08:25 -0000 Received: from redhat.com (localhost [127.0.0.1]) by localhost.redhat.com (Postfix) with ESMTP id 460DB2B2F; Mon, 5 May 2003 10:08:22 -0400 (EDT) Message-ID: <3EB67056.4070209@redhat.com> Date: Mon, 05 May 2003 14:08:00 -0000 From: Andrew Cagney User-Agent: Mozilla/5.0 (X11; U; NetBSD macppc; en-US; rv:1.0.2) Gecko/20030223 X-Accept-Language: en-us, en MIME-Version: 1.0 To: Daniel Jacobowitz Cc: Mark Kettenis , gdb-patches@sources.redhat.com Subject: Re: [PATCH/i386newframe/RFC] DWARF CFI frame unwinder References: <200305042207.h44M7gNG023734@elgar.kettenis.dyndns.org> <3EB5DBFF.6030009@redhat.com> <20030505034242.GA21263@nevyn.them.org> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-SW-Source: 2003-05/txt/msg00060.txt.bz2 >> >> This isn't right. It should return DW_AT_frame_base. However, since >> dwarf2expr.c doesn't yet use these methods it doesn't [?] really matter. >> Only affects ``info frame''. > I don't think it should. Er ... > The frame's CFA is the basis for identifying the frame and locating > saved registers in the CFI. It is always present when you have CFI. > > DW_AT_frame_base is the basis for locating saved variables and locals. > It is generally present when you have DWARF-2 debug info. You and I went through all this not too long ago. frame-base is for this high level thingie, frame-unwind is for the low level register information. > The two are not necessarily related. I don't remember how we settled > on providing DW_AT_frame_base. Possibly a debug info auxiliary to the > function symbol or to the block. > > > By the way, I don't remember something else I believe we've > discussed... Does each target that wants to use the CFI unwinder have > to add it in its gdbarch initialization? At present yes. Given the amount of upheval required before a target will work with this code, it doesn't really matter. As I,and now Mark, discovered, it is something of an all or nothing afair. Andrew