GDB 6.8 not working in remote debugging

[Michael Snyder]

You will need to take this issue up with whomever
supplied you with this gdb.  We dropped support for
version 6.8 a year ago.


Nikola Ikonic wrote:
> Hello,
> 
> I am trying to get GDB 6.8 work for remote debugging on ARC processor
> (TCP connection to gdbserver). I know that GDB has stopped supporting
> ARC, but there are some (or maybe have been) other parties that do
> develop support for this processor. I am writing this mail in hope
> that you will have some kind of idea where I could look for the
> solution of my problem. I would be very grateful for any kind of clue
> you could give me. So, the problem is following:
> 
> I have been using successfully GDB 6.6 for remote debugging (on ARC)
> so far, and have received 6.8 GDB for ARC, but it has problems
> connecting with the board. To be more precise, when I do
> 
> "target remote:2331"
> 
> I get this:
> 
> (gdb) target remote:2331
> Remote debugging using :2331
> 0x70000018 in ?? (),
> 
> where 0x70000018 is value of PC register. This value is wrong. I know
> that because when I do same thing in 6.6 GDB I get more reasonable
> values that are appropriate.
> 
> My first guess is that register numbers are not correct (e.g. PC
> register has wrong id or something similar).
> 
> I have tried to debug GDB 6.8 and put some breakpoints on functions
> that do JTAG reg_read and reg_write in order to see which register
> number is used for each register. But, it never hits those
> breakpoints, no matter what I do. It seems to me that register values
> are acquired through some kind of "frame history" (frame unwinding)
> and not through direct access on JTAG. Is my assumption correct?
> 
> So, I have couple of questions:
> 
> 1) Beside inappropriate register numbers, what else do you think could
> be wrong in having wrong PC value and connection to the board?
> 
> 2) Are JTAG functions actually used when accessing board through gdbserver?
> 
> 3) Through which functions (or modules in general) are registers
> accessed in remote debugging (we are talking about TCP connection to
> gdbserver)?
> 
> 4) If I am right about register Ids, do you have any ideas how could
> you determine this? Just some general idea wold be fine.
> 
> I know I have asked couple of overall questions that could overlap,
> but I would like to get clearer picture. Any suggestion would be much
> appreciated.
> 
> 
> Thank you very much in advance.
> 
> Best regards,
> 	Nikola