_rtld_free_tls
_rtld_free_tls(oldtcb, 2 * sizeof(uintptr_t),
__weak_reference(__libc_free_tls, _rtld_free_tls);
void _rtld_free_tls(void *tls, size_t tcbsize, size_t tcbalign);
_rtld_free_tls(tcb, TLS_TCB_SIZE, TLS_TCB_ALIGN);
void _rtld_free_tls(void *tcb, size_t tcbsize, size_t tcbalign) __exported;