Manual merge

mysql-test/t/func_gconcat.test

@@ -310,6 +310,13 @@ select a, group_concat(b order by b) from t1 group by a with rollup;
 select a, group_concat(distinct b order by b) from t1 group by a with rollup;
 drop table t1;
 
+#
+# Bug #6475
+#
+create table t1 (a char(3), b char(20), primary key (a, b));
+insert into t1 values ('ABW', 'Dutch'), ('ABW', 'English');
+select group_concat(a) from t1 group by b;
+drop table t1;
 #
 # Bug #12095: GROUP_CONCAT for one row table 
 #