c++ thread_local destructors with pthread destructors

I want to do some work after all C++ thread_local destructors called. This is platform specific – Android, so I have access to pthreads.

The question is, when pthread_key_created destructors should be called, before or after C++ thread_local destructors? Or they can be interleaved?

I tested On Linux Mint and pthread destructors called after C++ ‘s.

Answer

bionic/pthread_exit.cpp currently has the same order:

void pthread_exit(void* return_value) {
  // Call dtors for thread_local objects first.
  __cxa_thread_finalize();
  // Call the TLS destructors.
  pthread_key_clean_all();

However, this is not documented behavior and you should not build something relying on it.