Re: [PATCH v2 3/6] gdb/infcall: in condition evaluation register target back after infcall.

[Andrew Burgess <andrew.burgess@embecosm.com>]

* Natalia Saiapova via Gdb-patches <gdb-patches@sourceware.org> [2020-10-09 13:27:15 +0200]:

> After an inferior call is finished, the target is unregistered from
> the event loop.  However, if the inferior call has happened during
> the condition evaluation, we still want to get `stop` events from
> other threads in `wait_one`.  So, register the target back.

My first question after reading this patch and the commit message is,
why don't we stop the unregistering for the case when we shouldn't
unregister.

There's probably a really good answer, and you probably have all the
knowledge in your head.... but the commit message is a little terse.

Could you explain why it's better to let GDB do the wrong thing and
then patch it up, instead of just doing to right thing all along?

Also, it feels like this change should have a test.

Thanks,
Andrew





> 
> gdb/ChangeLog:
> 2020-08-26  Natalia Saiapova  <natalia.saiapova@intel.com>
> 	    Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
> 
> 	* infcall.c (run_inferior_call): In condition evaluation,
> 	register the target back after the infcall.
> 
> Co-authored-by: Natalia Saiapova <natalia.saiapova@intel.com>
> Co-authored-by: Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
> 
> Signed-off-by: Natalia Saiapova <natalia.saiapova@intel.com>
> ---
>  gdb/infcall.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/gdb/infcall.c b/gdb/infcall.c
> index 399b1724ea2..0b0226f8e82 100644
> --- a/gdb/infcall.c
> +++ b/gdb/infcall.c
> @@ -667,6 +667,9 @@ run_inferior_call (struct call_thread_fsm *sm,
>  
>    call_thread->control.in_infcall = saved_in_infcall;
>  
> +  if (call_thread->control.in_cond_eval && target_can_async_p ())
> +    target_async (true);
> +
>    return caught_error;
>  }
>  
> -- 
> 2.17.1
> 
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