Re: main thread pthread_exit/sys_exit bug!

[Oleg Nesterov <oleg@redhat.com>]

On 02/05, Roland McGrath wrote:
>
> I wrote this test case for it.  Is there any problem other than this one?

I don't know about other problems with the zombie leaders.

Except, I am worried whether the fix I have in mind is correct ;)
It is simple, wait_task_stopped() should do

	if we tracer:

		check ->state, eat ->exit_code

	else:
		check SIGNAL_STOP_STOPPED, use ->group_exit_code

This looks logical, and should fix the problem. But this is
the user-visible change. For example,

	$ sleep 100
	^Z
	[1]+  Stopped                 sleep 100
	$ strace -p `pidof sleep`
	Process 11442 attached - interrupt to quit

strace hangs in do_wait(). But after the fix strace will happily
proceed. I can't know whether this behaviour change is bad or not.

Oleg.