Comment 4 for bug 1255147

wsrep-5.6 build seems to run as expected for me:

Server version: 5.6.15-debug-log Source distribution, wsrep_25.2.r4032

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Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> show tables;
Empty set (0.00 sec)

mysql> CREATE TABLE t(p INT AUTO_INCREMENT PRIMARY KEY, u INT UNIQUE KEY);
Query OK, 0 rows affected (0.02 sec)

mysql> INSERT INTO t VALUES(1, 1);
Query OK, 1 row affected (0.00 sec)

mysql> INSERT INTO t VALUES(2, 1);
ERROR 1062 (23000): Duplicate entry '1' for key 'u'
mysql> INSERT IGNORE INTO t VALUES(2, 1);
Query OK, 0 rows affected (0.00 sec)

mysql> INSERT INTO t VALUES(DEFAULT, 1);
ERROR 1062 (23000): Duplicate entry '1' for key 'u'
mysql> INSERT IGNORE INTO t VALUES(DEFAULT, 1);
Query OK, 0 rows affected (0.00 sec)

mysql> select * from t;
+---+------+
| p | u |
+---+------+
| 1 | 1 |
+---+------+
1 row in set (0.00 sec)