K5_PTHREADS_LOADED
# define K5_PTHREADS_LOADED (&pthread_once != 0)
# define K5_PTHREADS_LOADED (&pthread_mutexattr_setrobust_np != 0)
# define K5_PTHREADS_LOADED (1)
# define K5_PTHREADS_LOADED (1)