From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 11286 invoked by alias); 28 Apr 2003 16:14:50 -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 11279 invoked from network); 28 Apr 2003 16:14:49 -0000 Received: from unknown (HELO crack.them.org) (146.82.138.56) by sources.redhat.com with SMTP; 28 Apr 2003 16:14:49 -0000 Received: from nevyn.them.org ([66.93.61.169] ident=mail) by crack.them.org with asmtp (Exim 3.12 #1 (Debian)) id 19ABHT-0003HW-00; Mon, 28 Apr 2003 11:15:03 -0500 Received: from drow by nevyn.them.org with local (Exim 3.36 #1 (Debian)) id 19ABHA-0007um-00; Mon, 28 Apr 2003 12:14:44 -0400 Date: Mon, 28 Apr 2003 16:37:00 -0000 From: Daniel Jacobowitz To: Andrew Cagney Cc: Mark Kettenis , colins@google.com, gdb-patches@sources.redhat.com Subject: Re: patch for printing 64-bit values in i386 registers; STABS format Message-ID: <20030428161443.GA30324@nevyn.them.org> Mail-Followup-To: Andrew Cagney , Mark Kettenis , colins@google.com, gdb-patches@sources.redhat.com References: <20030425213548.GA22505@nevyn.them.org> <3EA9B6AE.90001@redhat.com> <20030426015010.GA25355@nevyn.them.org> <3EA9F295.2090803@redhat.com> <20030426030534.GA26304@nevyn.them.org> <3EA9FDDF.8070205@redhat.com> <200304272203.h3RM35Ur016419@elgar.kettenis.dyndns.org> <3EAD474C.6090403@redhat.com> <20030428153247.GA28501@nevyn.them.org> <3EAD51F1.8050605@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <3EAD51F1.8050605@redhat.com> User-Agent: Mutt/1.5.1i X-SW-Source: 2003-04/txt/msg00523.txt.bz2 On Mon, Apr 28, 2003 at 12:08:17PM -0400, Andrew Cagney wrote: > > >>The stabs reader will need to be modified so that it generates a proper > >>location description. Note that it is STABS centric. dwarf2 doesn't > >>need that mechanism since (presumably) GCC is generating the correct > >>info (....). > > > > > >No, that's incorrect. GDB wouldn't even be able to find half the value > >if GCC was putting out correct information. We can't fix that until > >GDB is ready to not choke on the result. We will have to handle the > >incorrect debug info probably forever. > > I made two assertions: > > - stabs > - dwarf2 (where I included a ``presumably'') > > You're saying that both are incorrect? I guess that depends where you draw the line between the two assertions :) - It's not stabs centric; I imagine that if someone went in to update mdebug or hp support they'd have the same problem. Well, maybe not hp. That's a real kitchen sink format from what I recall. - generated dwarf2 is not correct but - stabs would have to be modified (if we did this fixup in each and every debug reader, instead of in read_var_value and friends; I see good arguments both ways) > >This is one of the intended purposes of this mechanism, and as I > >>indicated, is needed by MIPS. Being able to project an arbitrary [debug > >>info] view of the registers onto the raw register buffer. > >> > >>BTW, what happens when there is an attempt to write a long long value? > >>GDB again assumes that it can write to contigious registers - the reason > >>why REGISTER_BYTE can't be killed. > > > > > >That ugliness could go away too with Mark's introduced method. GDB > >could be fixed to find the next register properly. > > GDB also uses it to encode offsets into a register. It also does not > help the MIPS where the debug register does need to be projected into > the raw registers. Why have add more mechanisms when the existing one > is sufficient. Focus the effort on fixing the real problem. > > BTW, my comment about no names was wrong. They can be named, that > restriction should have been removed by the introduction of reggroups. Well, in that case I guess it would work. Let's do it? It still feels much more like a hack to me than Mark's approach; I'll just quietly disagree I suppose. -- Daniel Jacobowitz MontaVista Software Debian GNU/Linux Developer