[PATCH] signal: Use <sigsetops.h> for sigemptyset, sigfillset

[Florian Weimer]

* Florian Weimer:

> * Adhemerval Zanella via Libc-alpha:
>
>> On 22/04/2020 07:02, Florian Weimer wrote:
>>> * Florian Weimer:
>>> 
>>>> * Andreas Schwab:
>>>>
>>>>> On Apr 22 2020, Florian Weimer wrote:
>>>>>
>>>>>> * Andreas Schwab:
>>>>>>
>>>>>>> On Apr 22 2020, Florian Weimer wrote:
>>>>>>>
>>>>>>>> This avoids changing the entire sigset_t structure.  Updating the
>>>>>>>> actually used part is sufficient.
>>>>>>>
>>>>>>> I'm not sure it's a good idea to leave most of the structure
>>>>>>> uninitialized.
>>>>>>
>>>>>> Would you please elaborate?  How is this different from padding?
>>>>>
>>>>> Padding is always unnamed.
>>>>
>>>> Not if it is called __glibc_reserved.  I obviously meant named
>>>> padding.
>>> 
>>> And sigprocmask has always left the padding uninitialized (even before
>>> Adhemerval's changes).
>>
>> Should we change __sigemptyset/__sigfillset to fill the ununsed bits
>> instead?
>
> We would have to change sigprocmask as well.

Just to be clear: I don't think writing more data in sigprocmask is a
useful change.  We might even have to introduce a new symbol version.