// if ((errcode=pthread_key_delete(xbt_self_thread_key)))
// THROWF(system_error,errcode,"pthread_key_delete failed for xbt_self_thread_key");
// if ((errcode=pthread_key_delete(xbt_self_thread_key)))
// THROWF(system_error,errcode,"pthread_key_delete failed for xbt_self_thread_key");