compare_iov
if (!TEST_true(compare_iov(data_1 + 4, 3, iov, num_iov)))
if (!TEST_true(compare_iov(data_1, sizeof(data_1), iov, num_iov)))
if (!TEST_true(compare_iov(data_1 + 8, sizeof(data_1) - 8, iov, num_iov)))