[PATCH 1/3] nptl: Move pthread_sigmask implementation to libc

[Adhemerval Zanella]

On 13/03/2020 06:51, Florian Weimer wrote:
> * Adhemerval Zanella via Libc-alpha:
> 
>> diff --git a/sysdeps/unix/sysv/linux/aarch64/libc.abilist b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
>> index a4c31932cb..694efeb1e4 100644
>> --- a/sysdeps/unix/sysv/linux/aarch64/libc.abilist
>> +++ b/sysdeps/unix/sysv/linux/aarch64/libc.abilist
>> @@ -1447,6 +1447,7 @@ GLIBC_2.17 pthread_self F
>>  GLIBC_2.17 pthread_setcancelstate F
>>  GLIBC_2.17 pthread_setcanceltype F
>>  GLIBC_2.17 pthread_setschedparam F
>> +GLIBC_2.17 pthread_sigmask F
>>  GLIBC_2.17 ptrace F
>>  GLIBC_2.17 ptsname F
>>  GLIBC_2.17 ptsname_r F
>> diff --git a/sysdeps/unix/sysv/linux/aarch64/libpthread.abilist b/sysdeps/unix/sysv/linux/aarch64/libpthread.abilist
>> index d65beba958..48b368acb1 100644
>> --- a/sysdeps/unix/sysv/linux/aarch64/libpthread.abilist
>> +++ b/sysdeps/unix/sysv/linux/aarch64/libpthread.abilist
>> @@ -156,7 +156,6 @@ GLIBC_2.17 pthread_setconcurrency F
>>  GLIBC_2.17 pthread_setname_np F
>>  GLIBC_2.17 pthread_setschedprio F
>>  GLIBC_2.17 pthread_setspecific F
>> -GLIBC_2.17 pthread_sigmask F
>>  GLIBC_2.17 pthread_sigqueue F
>>  GLIBC_2.17 pthread_spin_destroy F
>>  GLIBC_2.17 pthread_spin_init F
> 
> This change is not fully compatible: Newly-linked programs may incur
> lazy binding failures on older glibc versions because pthread_sigmask
> is not present in libc.so.6.

But backward compatibility is not a fully support scenario. Do we
really need to handle such cases for the libpthread removal
project?

> 
> In other cases, we have added a compat symbol and a new symbol
> version.
>