RE: multithreaded remote debugging

["Frank van Eijkelenburg" <frank.van.eijkelenburg@technolution.nl>]

> > > > Hi, I'm new to gdb. I try to remote debug an application:
> > > >
> > > > I have a linux machine with redhat installed (2.4.7-10), this
> > > is the host.
> > > > On the target an ARM processor is running with linux kernel
> 2.4.16. I
> > > > compiled gdb on the host (with target arm-linux). I also
> cross-compiled
> > > > gdbserver. My application (which I want to debug) is compiled
> > > with compiler
> > > > option -g. I can start the gdbserver on the target and gdb on
> > > the host and
> > > > have a connection by tcp/ip. The application is multithreaded
> > > and uses the
> > > > libpthread library. If I ignore the SIG32 signal (with "handle
> > > SIG32 nostop"
> > > > and "handle SIG32 noprint") I can run the application. However,
> > > if I try to
> > > > execute "info threads" I only get information about one
> thread (the main
> > > > thread??). I can put breakpoints in the main thread and
> step through the
> > > > code, but if I put a breakpoint in another thread, the debugger
> > > will stop,
> > > > but I cannot step through the code:
> > > >
> > > > Program received signal SIGTRAP, Trace/breakpoint trap.
> > > > 0x400ab2e4 in ?? ()
> > > > (gdb) n
> > > > Cannot find bounds of current function
> > > >
> > > > What do I wrong or is it not possible to step through the
> code of other
> > > > threads beside the main thread?
> > >
> > > You neglected to say what version you're using.  We only got support
> > > for remote thread debugging between GDB 5.2 and 5.3; if you aren't
> > > using 5.3, you should try it.
> > >
> >
> > Sorry about that. I am using GDB version 5.3 with the above described
> > problems.
>
> Do you have libthread_db installed on your target, and on your cross
> development system so that gdbserver can link to it?  Look at the
> output of "configure" in the gdbserver directory, or at config.log.
>

I think the problem is in the libraries. I tried some simple sample code and
debugged this on the host machine (it was linking /lib/libpthread.so.0).
This worked like I expected (I could see multiple threads with the "info
threads" command).
Gdbserver is crosscompiled with the libthread_db.so.1, which is also
installed at the target. But the application is linked against a
libpthread.a.