Re: RFC: skip_inline_frames failed assertion resuming from breakpoint on LynxOS

[Joel Brobecker <brobecker@adacore.com>]

> > gdb/gdbserver/ChangeLog:
> > 
> >         * lynx-low.c (lynx_resume): Use PTRACE_SINGLESTEP_ONE if N == 1.
> >         Remove FIXME comment about assumption about N.
> > 
> > OK to commit?
> 
> Sure, OK.

Thank you, pushed!

> GDB nowadays sends a single vCont packet that both steps thread A,
> continues thread B with a signal and continues all other threads with
> no signal (previously in some cases it'd just lose control of the
> inferior, or deliver the signal to the wrong thread).  Something like:
> 
>   vCont;s:A;C SIG:B;c
[...]
> Couldn't you iterate over the threads, and use PTRACE_STEP_ONE
> for the stepped threads, and PTRACE_CONT_ONE for the others,
> instead of PTRACE_CONT ?  For the case above, lynx_resume would
> end up issuing:
> 
>  PTRACE_STEP_ONE, thread A, sig 0
>  PTRACE_CONT_ONE, thread B, sig SIG
>  PTRACE_CONT_ONE, thread C, sig 0
>  PTRACE_CONT_ONE, thread D, sig 0

Interesting. Do you mean sending those requests without waiting
for the inferior to stop? I'd have to verify that it's possible
to send ptrace requests while the inferior is "in flight", but
wouldn't you then have possible race conditions?

-- 
Joel