From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 888 invoked by alias); 22 Oct 2008 13:08:01 -0000 Received: (qmail 753 invoked by uid 71); 22 Oct 2008 13:08:01 -0000 Resent-Date: 22 Oct 2008 13:08:01 -0000 Resent-Message-ID: <20081022130801.749.qmail@sourceware.org> Resent-From: gdb-gnats@sources.redhat.com (GNATS Filer) Resent-To: gdb-prs@sources.redhat.com Resent-Reply-To: gdb-gnats@sources.redhat.com, Daniel Jacobowitz Received: (qmail 12897 invoked by uid 22791); 22 Oct 2008 13:00:49 -0000 Received: from mail.codesourcery.com (HELO mail.codesourcery.com) (65.74.133.4) by sourceware.org (qpsmtpd/0.31) with ESMTP; Wed, 22 Oct 2008 13:00:13 +0000 Received: (qmail 32214 invoked from network); 22 Oct 2008 13:00:11 -0000 Received: from unknown (HELO localhost) (dan@127.0.0.2) by mail.codesourcery.com with ESMTPA; 22 Oct 2008 13:00:11 -0000 Message-Id: <20081022130006.GY14714@caradoc.them.org> Date: Wed, 22 Oct 2008 13:08:00 -0000 From: Daniel Jacobowitz To: julien.lincy@thomson.net Cc: gdb-gnats@sources.redhat.com In-Reply-To: <20081022114101.8603.qmail@sourceware.org> References: <20081022114101.8603.qmail@sourceware.org> Subject: pending/2542: Re: ARM single step problem with instruction 0xa5ffffeb Mailing-List: contact gdb-prs-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-prs-owner@sourceware.org X-SW-Source: 2008-q4/txt/msg00024.txt.bz2 >Number: 2542 >Category: pending >Synopsis: Re: ARM single step problem with instruction 0xa5ffffeb >Confidential: yes >Severity: serious >Priority: medium >Responsible: unassigned >State: open >Class: change-request >Submitter-Id: unknown >Arrival-Date: Wed Oct 22 13:08:01 UTC 2008 >Closed-Date: >Last-Modified: >Originator: >Release: >Organization: >Environment: >Description: On Wed, Oct 22, 2008 at 11:41:01AM -0000, julien.lincy@thomson.net wrote: > >Description: > I have a problem single stepping with a simple C program on ARM, with the instruction 0xa5ffffeb. > > 8538: a5ffffeb ldrgeb pc, [pc, #4075]! ; 952b <__clz_tab+0x6b> > > GDB stops with the error "Invalid update to pc in instruction". > > The C program i'm trying to test is attached. > The ARM I use is an ARM v1136 (a bit specific...). I think there's something wrong with your environment. That's not a valid instruction; PC is always aligned, so pc+4075 is unaligned. The middle of __clz_tab doesn't have function pointers in it. And you can't do PC-relative loads with writeback. GDB is right to complain about that instruction. -- Daniel Jacobowitz CodeSourcery >How-To-Repeat: >Fix: >Release-Note: >Audit-Trail: >Unformatted: