Program received signal SIGTRAP, Trace/breakpoint ...

Article View: gnu.gdb.bug

Article #1302

#1302

From: David Xu
Date: Wed, 07 Jul 2004 06:33

24 lines
2612 bytes

I am writting pthread target module for FreeBSD 5,  I have patch for
gdb 5.2, that works fine, but because recently they imported gdb 6.1
into tree, I have updated my patch for gdb 6.1, and found it does not
work well,  when debugging a threaded process, I always get message
"Program received signal SIGTRAP, Trace/breakpoint ", 
<http://sources.redhat.com/ml/gdb/2003-05/msg00239.html>
and if I type "next", program crashes with SIGSEGV.
Deeply digging into gdb 6.1 source code, found that in file
infrun.c, function adjust_pc_after_break() sometimes does not
adjust pc, this happens when a new thread hits a breakpoint after
'next' command,
in the case, the following condition are true in adjust_pc_after_break() :
  software_breakpoint_inserted_here_p (stop_pc)
  currently_stepping (ecs)
  prev_pc != stop_pc
  step_range_end
the following condition is false:
   INNER_THAN (read_sp (), (step_sp - 16))

If I remove 'INNER_THAN' from the function, everything works again,
is the INNER_THAN condition meanful for new thread while inferior_ptid
is still referencing the previous waited ptid ?

David Xu

Technical Details

Message-ID: <mailman.65.1089181960.22971.bug-gdb@gnu.org>

Path: arc1-ca.pugleaf.net!g2news1.google.com!news1.google.com!newsfeed.stanford.edu!shelby.stanford.edu!not-for-mail

Show Full Headers

Complete Article Headers

X-Google-Thread: f5053,deb368898f79424a,start
X-Google-Attributes: gidf5053,public
X-Google-Language: ENGLISH,ASCII-7-bit
Path: arc1-ca.pugleaf.net!g2news1.google.com!news1.google.com!newsfeed.stanford.edu!shelby.stanford.edu!not-for-mail
From: David Xu <davidxu@freebsd.org>
Newsgroups: gnu.gdb.bug
Subject: Program received signal SIGTRAP, Trace/breakpoint ...
Date: Wed, 07 Jul 2004 14:33:23 +0800
Lines: 28
Approved: bug-gdb@gnu.org
Message-ID: <mailman.65.1089181960.22971.bug-gdb@gnu.org>
NNTP-Posting-Host: lists.gnu.org
Mime-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
X-Trace: news.Stanford.EDU 1089181833 25824 199.232.76.165 (7 Jul 2004 06:30:33 GMT)
X-Complaints-To: news@news.stanford.edu
To: bug-gdb@gnu.org
Envelope-to: bug-gdb@gnu.org
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US;
 rv:1.5b) Gecko/20030723 Thunderbird/0.1
X-Accept-Language: en-us, en
X-BeenThere: bug-gdb@gnu.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: "Bug reports for GDB, the GNU debugger" <bug-gdb.gnu.org>
List-Unsubscribe: <http://lists.gnu.org/mailman/listinfo/bug-gdb>,
 <mailto:bug-gdb-request@gnu.org?subject=unsubscribe>
List-Archive: <http://lists.gnu.org/pipermail/bug-gdb>
List-Post: <mailto:bug-gdb@gnu.org>
List-Help: <mailto:bug-gdb-request@gnu.org?subject=help>
List-Subscribe: <http://lists.gnu.org/mailman/listinfo/bug-gdb>,
 <mailto:bug-gdb-request@gnu.org?subject=subscribe>