From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gdb-prs-return-14234-listarch-gdb-prs=sources.redhat.com@sourceware.org>
Received: (qmail 13671 invoked by alias); 27 Aug 2013 17:04:12 -0000
Mailing-List: contact gdb-prs-help@sourceware.org; run by ezmlm
Precedence: bulk
List-Id: <gdb-prs.sourceware.org>
List-Subscribe: <mailto:gdb-prs-subscribe@sourceware.org>
List-Archive: <http://sourceware.org/ml/gdb-prs/>
List-Post: <mailto:gdb-prs@sourceware.org>
List-Help: <mailto:gdb-prs-help@sourceware.org>, <http://sourceware.org/lists.html#faqs>
Sender: gdb-prs-owner@sourceware.org
Received: (qmail 13647 invoked by uid 48); 27 Aug 2013 17:04:12 -0000
From: "jeremy.bennett at embecosm dot com" <sourceware-bugzilla@sourceware.org>
To: gdb-prs@sourceware.org
Subject: [Bug breakpoints/15902] New: Hardware watchpoints on remote targets
 do not automatically fall back to software watchpoints
Date: Tue, 27 Aug 2013 17:04:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: new
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gdb
X-Bugzilla-Component: breakpoints
X-Bugzilla-Version: HEAD
X-Bugzilla-Keywords: 
X-Bugzilla-Severity: normal
X-Bugzilla-Who: jeremy.bennett at embecosm dot com
X-Bugzilla-Status: NEW
X-Bugzilla-Priority: P2
X-Bugzilla-Assigned-To: unassigned at sourceware dot org
X-Bugzilla-Target-Milestone: ---
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields: bug_id short_desc product version bug_status
 bug_severity priority component assigned_to reporter attachments.created
Message-ID: <bug-15902-4717@http.sourceware.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://sourceware.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2013-q3/txt/msg00268.txt.bz2

https://sourceware.org/bugzilla/show_bug.cgi?id=15902

            Bug ID: 15902
           Summary: Hardware watchpoints on remote targets do not
                    automatically fall back to software watchpoints
           Product: gdb
           Version: HEAD
            Status: NEW
          Severity: normal
          Priority: P2
         Component: breakpoints
          Assignee: unassigned at sourceware dot org
          Reporter: jeremy.bennett at embecosm dot com

Created attachment 7168
  --> https://sourceware.org/bugzilla/attachment.cgi?id=7168&action=edit
Patch to update user manual for this issue.

The GDB manual (section 5.1.2, "Setting Watchpoints") states: "If gdb cannot
set a hardware watchpoint, it sets a software watchpoint,..."

This appears to only be true for native targets. On a remote target connecting
over Remote Serial Protocol, GDB will just report that hardware breakpoints are
not supported.

  Could not insert hardware breakpoints:
  You may have requested too many hardware breakpoints/watchpoints

The user must explicitly request software watchpoints using

  set can-use-hw-watchpoints 0

Problem found using GDB for ARC.

This really needs fixing in remote.c, but in the meantime, I attach a small
patch to the documentation:

2013-05-13  Jeremy Bennett  <jeremy.bennett@embecosm.com>

    * doc/gdb.texinfo (Setting Watchpoints): Note that automatic
    fallback to software watchpoints does not happen with remote
    targets.

-- 
You are receiving this mail because:
You are on the CC list for the bug.