Re: [PATCH] sim: don't rely on inferior_ptid in gdbsim_target::wait

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

* Simon Marchi <simon.marchi@polymtl.ca> [2020-01-18 22:55:57 -0500]:

> When running a program with the simulator target, I get:
> 
>     /home/simark/src/binutils-gdb/gdb/inferior.c:279: internal-error: inferior* find_inferior_pid(process_stratum_target*, int): Assertion `pid != 0' failed.
> 
> This can be reproduced by building a GDB for --target=arm-none-gnueabi,
> and running with
> 
>     $ ./gdb -nx --data-directory=data-directory a.out -ex "target sim" -ex load -ex "b main" -ex r
> 
> Where a.out is any program with a main.
> 
> The problem is that gdbsim_target::wait assumes that inferior_ptid has
> the value of the thread it wants to report an event for.
> 
> Actually, it's the target's responsibility to come up with the ptid of
> the thread the event is for.  In the sim target, that ptid is stored in
> sim_inferior_data::remote_sim_ptid, so return that instead of
> inferior_ptid.
> 
> ChangeLog:
> 
> 	* remote-sim.c (gdbsim_target::wait): Return
> 	sim_data->remote_sim_ptid instead of inferior_ptid.

This makes sense.  LGTM.

Thanks,
Andrew


> ---
>  gdb/remote-sim.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/gdb/remote-sim.c b/gdb/remote-sim.c
> index fb05786d4e28..d43648bd5171 100644
> --- a/gdb/remote-sim.c
> +++ b/gdb/remote-sim.c
> @@ -1016,7 +1016,7 @@ gdbsim_target::wait (ptid_t ptid, struct target_waitstatus *status, int options)
>        break;
>      }
>  
> -  return inferior_ptid;
> +  return sim_data->remote_sim_ptid;
>  }
>  
>  /* Get ready to modify the registers array.  On machines which store
> -- 
> 2.24.1
>