Sizes of winpthreads structs
-------------------------------
                     pthread_t    8
               pthread_attr_t_   32
              pthread_mutex_t_   32
          pthread_mutexattr_t_    4
            pthread_barrier_t_   48
        pthread_barrierattr_t_    8
                pthread_key_t_    4
               pthread_cond_t_  176
           pthread_condattr_t_    4
             pthread_rwlock_t_   48
         pthread_rwlockattr_t_    4
               pthread_once_t_    4
                   sched_param    4
-------------------------------