From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gdb-return-40115-listarch-gdb=sources.redhat.com@sourceware.org>
Received: (qmail 8561 invoked by alias); 31 Oct 2011 17:20:57 -0000
Received: (qmail 8533 invoked by uid 22791); 31 Oct 2011 17:20:55 -0000
X-SWARE-Spam-Status: No, hits=0.7 required=5.0	tests=AWL,BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FROM,RCVD_IN_DNSWL_LOW
X-Spam-Check-By: sourceware.org
Received: from mail-vw0-f41.google.com (HELO mail-vw0-f41.google.com) (209.85.212.41)    by sourceware.org (qpsmtpd/0.43rc1) with ESMTP; Mon, 31 Oct 2011 17:20:42 +0000
Received: by vws16 with SMTP id 16so707310vws.0        for <gdb@sourceware.org>; Mon, 31 Oct 2011 10:20:41 -0700 (PDT)
MIME-Version: 1.0
Received: by 10.68.33.42 with SMTP id o10mr24513612pbi.52.1320081640992; Mon, 31 Oct 2011 10:20:40 -0700 (PDT)
Received: by 10.68.43.137 with HTTP; Mon, 31 Oct 2011 10:20:40 -0700 (PDT)
In-Reply-To: <CABexPfEfZvFigThr0bVM6ReqagFsjSxwo=eaoHGSkkxnLYMVXQ@mail.gmail.com>
References: <CABexPfEfZvFigThr0bVM6ReqagFsjSxwo=eaoHGSkkxnLYMVXQ@mail.gmail.com>
Date: Mon, 31 Oct 2011 17:26:00 -0000
Message-ID: <CABexPfFR=pCHKW8sQ8=w5n+9u3dNirrEZRApp8ZD9u7qhsEoLQ@mail.gmail.com>
Subject: How "can't compute CFA for this frame" and "No enough registers or memory available to unwind further" happens?
From: zhihua che <zhihua.che@gmail.com>
To: gdb <gdb@sourceware.org>
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
X-IsSubscribed: yes
Mailing-List: contact gdb-help@sourceware.org; run by ezmlm
Precedence: bulk
List-Id: <gdb.sourceware.org>
List-Subscribe: <mailto:gdb-subscribe@sourceware.org>
List-Archive: <http://sourceware.org/ml/gdb/>
List-Post: <mailto:gdb@sourceware.org>
List-Help: <mailto:gdb-help@sourceware.org>, <http://sourceware.org/ml/#faqs>
Sender: gdb-owner@sourceware.org
X-SW-Source: 2011-10/txt/msg00240.txt.bz2

Hi, everyone
=A0 =A0 =A0 =A0I'm not sure this is right place for the help. I'm writing a
toy os and coding with mixed assembly and C language, debugging with
GDB. But I'm trapped with an annoying problem. This is my situation:
During the os booting time, after the os control transfers from real
mode assembly codes to real mode C codes, I wish I can exam the stack
frames and local variable as I do in regular application program, but
I always get "can't compute CFA for this frame" or "No enough
registers or memory=A0available to further unwind" if I issue "print
xxx" or "backtrace" command respectivelly. The codes seem work, but I
can only exam registers or memory using "info reg" or "x" command,
it's way unfriendly and time-consuming. I have searched a lot but
don't figure out how these happen. I need your help. Thanks.
Harvey