RE: Error running remote gdb

[Michael Snyder <Michael.Snyder@palmsource.com>]

On Wed, 2006-09-06 at 04:47 -0700, Bizhan Gholikhamseh (bgholikh) wrote:
>  
> >The last message from gdb to the target, "$vCont;s:6098;c#67", doesn't
> seem to make sense.  Personally I don't >understand the semantics of
> vCont well enough to say for sure.
> >
> >Fortunately, vCont can be turned off.   ;-)
> >
> >Can you repeat the experiment approximately like this?
> >	% gdb test
> >	(gdb) set debug remote 1
> >	(gdb) set remote verbose-resume off
> >	(gdb) target remote 172.28.176.142:2001
> >	(gdb) break main
> >	(gdb) continue
> >	(gdb) where
> >	(gdb) step
> 
> >Send us the result just like before.
> 
> The output was too long to cut and paste so I attached the log file. 

Bizhan, you're changing too many things between one experiment
and the next.  This seems to be a completely different program
from the last one -- and you seem to have profiling turned on now, 
which wasn't present last time.

OK, well, here are the interesting parts:

(gdb) set debug remote 1
(gdb) set remote verbose-resume-packet off
(gdb) target remote 172.20.233.74:1234
0x30010390 in ?? ()
(gdb) break main
(gdb) continue
Continuing.
Sending packet: $M3000ce98,4:7d821008#b1...Ack
Packet received: OK
Sending packet: $m100413ec,4#be...Ack
Packet received: 3860000d
Sending packet: $M100413ec,4:7d821008#a6...Ack
Packet received: OK
Sending packet: $c#63...Ack

Set breakpoints at 3000ce98 and 100413ec, and continue.

Packet received: T0501:7ffff8e0;40:3000ce98;
Sending packet: $m3000ce98,4#c9...Ack
Packet received: 7d821008
Sending packet: $M3000ce98,4:9421fff0#15...Ack
Packet received: OK
Sending packet: $m100413ec,4#be...Ack
Packet received: 7d821008
Sending packet: $M100413ec,4:3860000d#9d...Ack
Packet received: OK

Trap at 3000ce98 -- remove breakpoints.

Sending packet: $s#73...Ack
Packet received: T0501:7ffff8d0;40:3000ce9c;thread:1e80;
Sending packet: $m3000ce98,4#c9...Ack
Packet received: 9421fff0
Sending packet: $M3000ce98,4:7d821008#b1...Ack
Packet received: OK
Sending packet: $m100413ec,4#be...Ack
Packet received: 3860000d
Sending packet: $M100413ec,4:7d821008#a6...Ack
Packet received: OK
Sending packet: $Hc0#db...Ack
Packet received: E01
Sending packet: $c#63...Ack
Packet received: T0501:7ffffe00;40:3000ce98;thread:1e80;

Single-step once to get past the breakpoint location.
Then re-insert the breakpoints, and continue.
Trap again at 3000ce98 -- remove the breakpoints.
This repeats a few more times.  

Finally...

Sending packet: $c#63...Ack
Packet received: T1b01:7ffffb30;40:30008a08;thread:1e80;
Sending packet: $C1b#d6...Ack

We received a signal 0x1b (SIGPROF), passed it on to the
target, and continued.

Packet received: T0501:7ffffe00;40:3000ce98;thread:1e80;
Sending packet: $m3000ce98,4#c9...Ack
Packet received: 7d821008
Sending packet: $M3000ce98,4:9421fff0#15...Ack
Packet received: OK
Sending packet: $m100413ec,4#be...Ack
Packet received: 7d821008
Sending packet: $M100413ec,4:3860000d#9d...Ack
Packet received: OK
Sending packet: $s#73...Ack
Packet received: T1b01:7ffffe00;40:3000ce98;thread:1e80;

We remove the breakpoints, single-step, but receive SIGPROF.


Sending packet: $S1b#e6...Ack
Packet received: T0501:7ffff8c0;40:0fed6adc;thread:1e80;

So we singlestep again, passing the SIGPROF on to the target.
However, after this singlestep, we seem to land in a random
location (0x0fed6adc).

Anyway, we re-insert the breakpoints, continue, and *eventually*...

Sending packet: $c#63...Ack
Packet received: T0501:7ffffdb0;40:100413ec;thread:1e80;
[Switching to thread 7808]

We arrive at main, remove the breakpoints, and stop.


Breakpoint 1, main (argc=1, argv=0x7ffffe44) at main_cma.cpp:13
13              signal(SIGPIPE, SIG_IGN);
(gdb) where
#0  main (argc=1, argv=0x7ffffe44) at main_cma.cpp:13
(gdb) step


And here's the funky part...

Sending packet: $m3000ce98,4#c9...Ack
Packet received: 9421fff0
Sending packet: $M3000ce98,4:7d821008#b1...Ack
Packet received: OK
Sending packet: $m100413ec,4#be...Ack
Packet received: 3860000d
Sending packet: $M100413ec,4:7d821008#a6...Ack
Packet received: OK
Sending packet: $s#73...Ack
Packet received: T0501:7ffffdb0;40:100413ec;thread:1e80;


At this point, gdb re-inserts the breakpoints, then single-steps.
Of course, it immediately encounters the breakpoint at main again.

This is incorrect behavior on gdb's part.  I don't readily know 
how to explain it.  Let's see... here's your configuration:

This GDB was configured as "--host=i686-pc-linux-gnu
--target=powerpc-linux-gnuspe"...



By the way, what does "powerpc-linux-gnuspe"... mean?