Error 1248: Every derived table must have its own alias - mysql

Question

Please see my code, below. I get the error:
Error 1248: Every derived table must have its own alias
What am I doing wrong?
CREATE PROCEDURE `insert_seance` (IN compared_id INT)
BLOCK1: BEGIN
CREATE TEMPORARY TABLE log
LIKE seance_log;
CREATE TEMPORARY TABLE compared_log
LIKE seance_log;
BLOCK2: BEGIN
DECLARE done, inner_done BOOLEAN DEFAULT FALSE;
DECLARE diff BOOL DEFAULT TRUE;
DECLARE current_id, se_id, q_id, ans INT;
DECLARE compared CURSOR FOR
SELECT seance_id, question_id, answer FROM seance_log
WHERE seance_id = compared_id;
DECLARE seance CURSOR FOR
SELECT seance_id FROM seances
WHERE seance_id <> compared_id;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET done = TRUE;
OPEN compared;
WHILE NOT done DO
FETCH compared INTO se_id, q_id, ans;
INSERT INTO compared_log (seance_id, question_id, answer)
VALUES (se_id, q_id, ans);
END WHILE;
CLOSE compared;
SET done = FALSE;
OPEN seance;
WHILE NOT done DO
FETCH seance INTO current_id;
DELETE FROM log;
BLOCK3: BEGIN
DECLARE answers CURSOR FOR
SELECT seance_id, question_id, answer FROM seance_log
WHERE seance_id = current_id;
DECLARE CONTINUE HANDLER FOR NOT FOUND SET inner_done = TRUE;
DELETE FROM log;
OPEN answers;
WHILE NOT inner_done DO
FETCH answers INTO se_id, q_id, ans;
INSERT INTO log (seance_id, question_id, answer)
VALUES (se_id, q_id, ans);
END WHILE;
CLOSE answers;
SELECT IF ((SELECT COUNT(*) FROM (SELECT 'log' AS `set`, l.*
FROM log l
WHERE ROW(l.seance_id, l.question_id, l.answer) NOT IN
(SELECT * FROM compared_log)
UNION ALL
SELECT 'compared_log' AS `set`, cl.*
FROM compared_log cl
WHERE ROW(cl.seance_id, cl.question_id, cl.answer) NOT IN
(SELECT * FROM log)
)),FALSE,TRUE) INTO diff;
CASE WHEN diff = FALSE
THEN DELETE FROM seance_log
WHERE seance_id = compared_id;
UPDATE seances SET count = count + 1
WHERE seance_id = compared_id;
END CASE;
SET done = NOT diff;
END BLOCK3;
END WHILE;
CLOSE seance;
END BLOCK2;
END BLOCK1