Re: [PATCH v2 02/10] Finish move of clock_* functions to libc.

[Adhemerval Zanella <adhemerval.zanella@linaro.org>]

On 03/09/2019 10:31, Florian Weimer wrote:
> * Adhemerval Zanella:
> 
>> On 03/09/2019 04:29, Florian Weimer wrote:
>>> * Zack Weinberg:
>>>
>>>> diff --git a/rt/Versions b/rt/Versions
>>>> index 91e3fd2a20..84d1345420 100644
>>>> --- a/rt/Versions
>>>> +++ b/rt/Versions
>>>> @@ -1,15 +1,3 @@
>>>> -libc {
>>>> -  GLIBC_2.17 {
>>>> -    # c*
>>>> -    clock_getres; clock_gettime; clock_settime; clock_getcpuclockid;
>>>> -    clock_nanosleep;
>>>> -  }
>>>> -  GLIBC_PRIVATE {
>>>> -    __clock_getres; __clock_gettime; __clock_settime; __clock_getcpuclockid;
>>>> -    __clock_nanosleep;
>>>> -  }
>>>> -}
>>>
>>> Sorry, you cannot remove the GLIBC_2.17 symbol version in this way,
>>> otherwise old binaries will fail to load.  You need to leave behind a
>>> dummy function definition.  See __libpthread_version_placeholder for how
>>> I handled this in the libpthread/vfork case.
>>
>> Are you sure about it?
> 
> Yes. 8-)  But I missed that this block was just moved to time/Versions.
> Either place will work and generate the same symbol versions.

Right, because that was my understanding (the symbol versions will still
be generated correctly on libc).

> 
> For librt proper, the problem does not arise because sem_open is still
> present at the same symbol version, keeping the version present and
> alive.
> 
> Zack, please disregard my comment about rt/Versions.
> 
> Thanks,
> Florian
>