[PATCH v2 1/4] support: Add support_wait_for_thread_exit

[Adhemerval Zanella]

On 29/09/2021 17:27, Florian Weimer via Libc-alpha wrote:
> * Florian Weimer via Libc-alpha:
> 
>> +      int task_tid = atoi (e->d_name);
>> +      if (task_tid <= 0)
>> +        FAIL_EXIT1 ("Invalid /proc/self/task entry: %s", e->d_name);
> 
> There's a kernel bug that causes /proc/self/task/0 to be listed
> due to concurrent task exit in the kernel.
> 
> =====FAIL: nptl/tst-pthread_cancel-exited.out=====
> error: support_wait_for_thread_exit.c:51: Invalid /proc/self/task entry: 0
> error: 1 test failures
> =====FAIL: nptl/tst-pthread_cancel-exited.test-result=====
> 
> Should work around this in our test code?

I have see this failures in some tests run and I was about to bring
this to you.  Can we safely mitigate it by ignoring the tid '0'?