On Thu, Oct 04, 2012 at 01:38:38PM -0400, Jason Merrill wrote:
> commit 18c01be0ec8b7a3cda6a16e86356e8e434c12f89
> Author: Jason Merrill <ja...@redhat.com>
> Date: Thu Sep 20 16:00:08 2012 -0400
>
> Support C++11 thread_local destructors.
> libstdc++-v3/
> * libsupc++/cxxabi.h: Declare __cxa_thread_atexit.
> * libsupc++/atexit_thread.cc: New.
> * libsupc++/Makefile.am (nested_exception.lo): Add it.
> * config/abi/pre/gnu.ver: Add __cxa_thread_atexit.
If we want to add it to glibc, then it shouldn't be exported
from libstdc++ (or perhaps only as a fallback implementation;
the question is what to do if non-Linux targets add __cxa_thread_atexit
to their C libraries). If this is a fallback implementation, then it
needs to have some destructor that will call pthread_key_delete
(well, its __gthread_* wrapper), so that it libstdc++.so is dlclosed,
things don't crash (well, they likely will anyway if the C++ shared
library using thread_local destructors is dlclosed with multiple running
threads, but in the libstdc++ case it is at least avoidable).
Jakub
