Re: debug of multithreaded program turns to be impossible during execution

On 08/14/2014 04:52 PM, Avi Gozlan wrote:
> GDB 7.8 yields a similar behavior:
> 
> (gdb) c
> Continuing.
> ...
> [New Thread 0x43c05940 (LWP 3311)]
> [New Thread 0x44606940 (LWP 3312)]
> ...
> [Thread 0x44606940 (LWP 3312) exited]
> [Switching to Thread 0x43c05940 (LWP 3311)]
> Cannot remove breakpoints because program is no longer writable.
> Further execution is probably impossible.
> 0x00002aaaab98348f in start_thread () from /lib64/libpthread.so.0
> ptrace: No such process.
> (gdb) [Thread 0x46409940 (LWP 3315) exited]
> [Thread 0x45a08940 (LWP 3314) exited]
> [Thread 0x43c05940 (LWP 3311) exited]
> [Inferior 1 (process 3268) exited normally]
> 
> The only difference is that in 7.8 case, GDB continues automatically after giving the ptrace message.

Any chance you could try your reproducer with a more recent
system?  Mainly, I'm wondering whether kernel/glibc are at play here.

Also, a run with:

 set debug infrun 1
 set debug target 1
 set debug lin-lwp 1

may help diagnose the issue.

Thanks,
Pedro Alves