Re: [PATCH] nptl: Move pthread_attr_getdetachstate implementation into libc

[Florian Weimer <fweimer at redhat dot com>]

* Adhemerval Zanella:

> Why do we need this on libc? Can't we just remove the FORWARD and make
> it only on libpthread?

That would be a hard ABI break.

> My understanding is we need to move pthread_* implementation to libc only
> when they are actually used in libc.so, otherwise we can just cleanup the
> fowards instead.

I'm sorry, but that's not possible.  For example, pthread_mutex_lock is
used by many programs which do not link against libpthread.

My eventual goal is to make libpthread completely empty except for the
odd compatibility symbol, and advise programmers to use
__libc_single_threaded for atomics optmizations.  Using the presence of
libpthread hasn't worked well for quite a while because libpthread is
loaded pervasively, even by single-threaded programs.

Once pthread_create is in libc, we can move timer_create into libc as
well, greatly reducing the risk of underlinking and its hard-to-diagnose
error.

Thanks,
Florian