Remote debugging with GDB...

QNX USERS QNX6 - OS
1

Has anybody ever set up remote debugging using XEmacs (on Win32) and GDB (on QNX)? I’m particularly interested in QNX on non-x86 targets.

2

You want to use XEmacs on Win32 and have the Momentics SE/PE tools installed on Win32 and you want to target a remote QNX machine?

3

Yep, that’s it exactly. I have XEmacs and Momentics SE installed on my Win32 machine; I would like to use gud-mode to interact with a remote QNX machine. (I’ll be targeting both x86 and sh4 platforms, if that makes any difference.)

4

We have our own extension protocol to gdb for talking to pdebug (our debug agent). So if you simply tell Xemacs to use nto-gdb and then use the “target qnx hostname:port” command to get gdb to connect. On the remote target have both qconn and pdebug in your boot image and simply have qconn running. Then use the hostname/ip of your target on port 8000.

5

OK, I’ve told Xemacs to use ntox86-gdb, and it starts up ok.

But when I try to set the target, I get:

(gdb) target qnx 192.168.1.66:8000
Remote debugging using 192.168.1.66:8000
MsgNak received - resending

This doesn’t look good. When I try to load the executable, I get
(gdb) load
Loading section .interp, size 0x14 lma 0x80480f4
Memory access error while loading section .interp.

Well, that doesn’t look good. What am I doing wrong?

6

Are you running qconn/pdebug on the remote target?

7

QConn is running, although psin doesn’t seem to find pdebug.

8

You only need to check for pdebug once you have connected with gdb. Just to eliminate Xemacs, if you do this from the command line in a bash session, does it work any better?

9

Just tried this from the command line, and I get the same results:
(gdb) target qnx 192.168.1.66:8000
Remote debugging using 192.168.1.66:8000
MsgNak received - resending
(gdb) load
Loading section .interp, size 0x14 lma 0x80480f4
Memory access error while loading section .interp.
(gdb)

One question - where in the file system does the program get copied to? Or am I supposed to copy the program over manually before running gdb?

If I copy the program manually, how does gdb know what the remote file name is?

10

qnx.com/developer/docs/momen … html#DEBUG

Read that. :slight_smile:

11

Hi,

I’m trying to debug a programm at a remote qnx-machine.

I go through the following steps:

  • devc-pty -n 32 & (remote target)

  • pdebug 8000 & (remote target)

    (host qnx-system)

  • gdb -quiet

  • (gdb) target qnx 192.168.50.12:8000
    Remote debugging using 192.168.50.12:8000

  • upload program /tmp/program

  • (gdb) sym program
    Reading symbols from program…done.

  • (gdb) run /tmp/program
    Starting program: /tmp/program

  • (gdb) break main
    Breakpoint 1 at 0x804c11e: file program.cpp, line 5.

  • (gdb) c
    Continuing.

After the last step the debug session stops…nothing happens.
How can I resolve this problem?

12

do

  • (gdb) break main
    earlier than
  • (gdb) run /tmp/program

all is going well.

When you run, very fast main will be executed. typing break cannot catch it. right.
I am doing based on qconn on target, and gdb, actually ntoppc-gdb, run on host. trying to integrate it with code::blocks IDE… :smiley: :smiley: