Re: TLS on powerpc(32/64)

[Prosun Niyogi <niyogip@yahoo.com>]

How can I tell whether GDB is loading libthread_db?
"info threads" works... I would think libthread_db
must be loaded for that to work.
 
Also, in gdb(linux-thread_db.c) -
 
 __/* glibc doesn't provide the needed interface.  */
 if (!td_thr_tls_get_addr_p)
   throw_error (TLS_NO_LIBRARY_SUPPORT_ERROR,
                _("No TLS library support"));
 __/* Caller should have verified that lm != 0.  */
 gdb_assert (lm != 0);
 __/* Get info about the thread.  */
 thread_info = find_thread_pid (ptid);
 thread_db_map_id2thr (thread_info, 1);
 __/* Finally, get the address of the variable.  */
 err = td_thr_tls_get_addr_p
(&thread_info->private->th, (void *) lm,
                              offset, &address);
So the glibc interface is found... does that not mean
that libthread_db is loaded and found by GDB?
 
Apologies for the ignorance, just looking for how I
can check to see why td_thr_tls_get_addr_p() doesnt
return an appropriate value.
 
So judging from the tone of your comment, I should
expect to be able to print the value of a __thread
variable on ppc64, and there arent any known issues
preventing me from doing so? I have tried on SLES, FC,
and now cvs-head, and all three have failed.
 
Can you suggest where I should look next? I took a
quick look at libthread_db in glibc, and it looks like
none of the fuctions have changed in libc. 
 
Thanks,
 
Prosun Niyogi

--- Daniel Jacobowitz <drow@false.org> wrote:

> On Thu, Sep 21, 2006 at 04:20:47PM -0700, Prosun
> Niyogi wrote:
> > Hi, 
> > I've been struggling the last few days on getting
> gdb
> > to work correctly on a powerpc64 machine. Built as
> > ppc-64-linux, debugging ppc64 binaries linked
> against
> > libpthread. It seems to me that gdb's TLS access
> does
> > not work correctly on these platforms. Attempting
> to
> > print a variable of type __thread doesnt work. 
> 
> It looks to me like GDB has failed to load
> libthread_db for some
> reason.  I don't know why not; you'll have to look
> into it.
> 
> -- 
> Daniel Jacobowitz
> CodeSourcery
> 


__________________________________________________
Do You Yahoo!?
Tired of spam?  Yahoo! Mail has the best spam protection around 
http://mail.yahoo.com