Re: [PATCH v8] linux: Do not spawn a new thread for SIGEV_THREAD (BZ 30558, 27895, 29705, 32833)

On 7/8/26 4:04 PM, Carlos O'Donell wrote:
> On 7/8/26 3:45 PM, Adhemerval Zanella Netto wrote:
>>
>>
>> On 08/07/26 15:05, Carlos O'Donell wrote:
>>> On 7/7/26 11:59 AM, Adhemerval Zanella wrote:
>>>> The current timer_create SIGEV_THREAD implementation has some
>>>> downsides:
>>>
>>> Test rt/tst-timer8.c fails if pause() is removed indicating something is
>>> wrong with the asynchronous cancellation.
>>>
>>> Note that pause() should be removed because it's a cancellation point
>>> which causes the thread to test for cancellation, and it will see the
>>> bits set by pthread_cancel and cancel.
>>>
>>> I don't know why the newe implementation fails to cancel the thread, I just
>>> know that without pause it should still cancel but doesn't.
>> It is because the test is built with -fexception and gcc gives the notification
>> function a DWARF/LSDA unwind whose cleanup actions exist only at call sites.
>> Asynchronous cancellation that interrupts a PC not inside any call-site region
>> finds no landing pad there (the while (1)), so the personality routine performs
>> no cleanup for that frame (the on_cancel registered with pthread_cleanup_push)
>> and the unwind proceeds straight to thread termination.
> 
> Agreed, this means the test needs -fasynchronous-unwind-tables.

The test already has "-fasynchronous-unwind-tables"?

-- 
Cheers,
Carlos.