[review v2] infrun: handle already-exited threads when attempting to stop

[Tankut Baris Aktemur (Code Review)]

Tankut Baris Aktemur has posted comments on this change.

Change URL: https://gnutoolchain-gerrit.osci.io/r/c/binutils-gdb/+/133
......................................................................


Patch Set 2:

(1 comment)

> Patch Set 2:
> 
> FTR, I build patchset 2 and tested the example from PR25478, and hit an assert:
> ...

I was not able to repeat the problematic scenario with the current master.  The multi-target feature seems to have changed the behavior.  I'll need to first look into whether I can reproduce the infinite loop.

| --- gdb/infrun.c
| +++ gdb/infrun.c
| @@ -4494,0 +4500,19 @@ stop_all_threads (void)
| +
| +		  /* Set the threads as non-executing to avoid infinitely
| +		     waiting for them to stop.  */
| +		  mark_non_executing_threads (event_ptid, ws);
| +
| +		  if (ws.kind == TARGET_WAITKIND_NO_RESUMED)
| +		    {
| +		      /* Do nothing.  Already marked the threads.  */
| +		    }
| +		  if (ws.kind == TARGET_WAITKIND_THREAD_EXITED)

PS2, Line 4509:

Oops, yes.  Thanks for spotting that.

| +		    delete_thread (t);
| +		  else
| +		    {
| +		      /* TARGET_WAITKIND_EXITED or
| +			 TARGET_WAITKIND_SIGNALLED.  */
| +		      /* Need to restore the context because
| +			 handle_inferior_exit switches it.  */
| +		      scoped_restore_current_pspace_and_thread restore;
| +		      handle_inferior_exit (event_ptid, ws);

-- 
Gerrit-Project: binutils-gdb
Gerrit-Branch: master
Gerrit-Change-Id: I7cec98f40283773b79255d998511da434e9cd408
Gerrit-Change-Number: 133
Gerrit-PatchSet: 2
Gerrit-Owner: Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
Gerrit-Reviewer: Luis Machado <luis.machado@linaro.org>
Gerrit-Reviewer: Pedro Alves <palves@redhat.com>
Gerrit-Reviewer: Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
Gerrit-CC: Tom de Vries <tdevries@suse.de>
Gerrit-Comment-Date: Thu, 30 Jan 2020 16:30:06 +0000
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Comment-In-Reply-To: Tom de Vries <tdevries@suse.de>
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