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From: Roland McGrath <roland@redhat.com>
To: Oleg Nesterov <oleg@redhat.com>
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Cc: Kaz Kylheku <kkylheku@gmail.com>, linux-kernel@vger.kernel.org,
       Andrew Morton <akpm@linux-foundation.org>,
       Ulrich Drepper <drepper@redhat.com>
Subject: Re: main thread pthread_exit/sys_exit bug!
In-Reply-To: Oleg Nesterov's message of  Thursday, 5 February 2009 17:15:44 +0100 <20090205161544.GA24799@redhat.com>
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Date: Thu,  5 Feb 2009 13:22:34 -0800 (PST)
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> Yes we have the bug, and wait_task_stopped() should be fixed. But it is
> buggy anyway, even if we delay the death of the main thread. But I also
> think we shouldn't.

Sorry, I'd missed the actual bug report among all the tangential verbiage.
I wrote this test case for it.  Is there any problem other than this one?


Thanks,
Roland

==========

#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <signal.h>
#include <pthread.h>
#include <assert.h>

static void *
thfunc (void *arg)
{
  sleep (2);
  puts ("stopping");
  raise (SIGSTOP);
  puts ("resumed");
  exit (0);
}

int
main (void)
{
  pthread_t th;
  int rc = pthread_create (&th, NULL, &thfunc, NULL);
  assert_perror (rc);
  pthread_exit (0);
  /*NOTREACHED*/
  return 1;
}