Re: [PATCH] nptl: Add missing __pthread_cond_wait alias in static builds

[Florian Weimer <fweimer@redhat.com>]

* Jonathan Nieder:

> Hi,
>
> Florian Weimer wrote:
>
>> Fixes commit cf3fff1c195f859ba949a7ad86d4fca70bd99740 ("nptl: Move
>> cnd_wait into libc").
>>
>> I think this is the only missing strong_alias.  The other places either
>> have a matching versioned_symbol for the __pthread_ internal alias,
>> already define the strong alias, or there are no internal callers.
>>
>> Tested on i686-linux-gnu and x86_64-linux-gnu.  Built with
>> build-many-glibcs.py.
>>
>> Thanks,
>> Florian
>> ---
>>  nptl/pthread_cond_wait.c | 3 +++
>>  1 file changed, 3 insertions(+)
>>
>> diff --git a/nptl/pthread_cond_wait.c b/nptl/pthread_cond_wait.c
>> index 54e504a6b5..409a99ecb7 100644
>> --- a/nptl/pthread_cond_wait.c
>> +++ b/nptl/pthread_cond_wait.c
>> @@ -622,6 +622,9 @@ ___pthread_cond_wait (pthread_cond_t *cond, pthread_mutex_t *mutex)
>>  versioned_symbol (libc, ___pthread_cond_wait, pthread_cond_wait,
>>  		  GLIBC_2_3_2);
>>  libc_hidden_ver (___pthread_cond_wait, __pthread_cond_wait)
>> +#ifndef SHARED
>> +strong_alias (___pthread_cond_wait, __pthread_cond_wait)
>> +#endif
>
> It took me a while to catch what is going on here: the left-hand side
> has *three* underscores, while the right-hand side has the usual two.
> I think the three underscores means it's not meant to be exported, but
> I'm not sure; is there some documentation that covers the conventions
> in this area?
>
> In any event, this matches the code in similar cases, so in addition
> to getting the job done it's improving consistency. :)  So,
>
> Reviewed-by: Jonathan Nieder <jrnieder@gmail.com>

Thanks.

Unfortunately, there is no consistent convention.  We recently gained
the ability to set multiple symbol versions on the same symbol, and
before that, …_1 and …_2 aliases were sometimes used.  I hope get rid of
the macro bits eventually and switch to something more palatable, but I
don't know what that would like.  Maybe we should rewrite the object
files with the symbol data we want, I'm not sure.  Or generate source
code snippets that can be #include'd at the end of source files that
define a public function.

Florian