Merge of fix for bug#59308 from mysql-5.1 -> mysql-5.5

mysql-test/r/order_by.result

@@ -1639,6 +1639,31 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	index	NULL	a	8	NULL	10	Using index; Using temporary; Using filesort
 1	SIMPLE	t2	eq_ref	PRIMARY	PRIMARY	4	test.t1.b	1	Using where
 DROP TABLE t1, t2;
+#
+# Bug #59110: Memory leak of QUICK_SELECT_I allocated memory 
+#  and
+# Bug #59308: Incorrect result for 
+SELECT DISTINCT <col>... ORDER BY <col> DESC 
+
+# Use Valgrind to detect #59110!
+#
+CREATE TABLE t1 (a INT,KEY (a));
+INSERT INTO t1 VALUES (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
+EXPLAIN SELECT DISTINCT a,1 FROM t1 WHERE a <> 1 ORDER BY a DESC;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	index	a	a	5	NULL	10	Using where; Using index; Using filesort
+SELECT DISTINCT a,1 FROM t1 WHERE a <> 1 ORDER BY a DESC;
+a	1
+10	1
+9	1
+8	1
+7	1
+6	1
+5	1
+4	1
+3	1
+2	1
+DROP TABLE t1;
 End of 5.1 tests
 #
 # Bug #38745: MySQL 5.1 optimizer uses filesort for ORDER BY

mysql-test/t/order_by.test

@@ -1493,6 +1493,23 @@ LIMIT 2;
 DROP TABLE t1, t2;
 
 
+--echo #
+--echo # Bug #59110: Memory leak of QUICK_SELECT_I allocated memory 
+--echo #  and
+--echo # Bug #59308: Incorrect result for 
+--echo               SELECT DISTINCT <col>... ORDER BY <col> DESC 
+--echo
+--echo # Use Valgrind to detect #59110!
+--echo #
+
+CREATE TABLE t1 (a INT,KEY (a));
+INSERT INTO t1 VALUES (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
+
+EXPLAIN SELECT DISTINCT a,1 FROM t1 WHERE a <> 1 ORDER BY a DESC;
+SELECT DISTINCT a,1 FROM t1 WHERE a <> 1 ORDER BY a DESC;
+
+DROP TABLE t1;
+
 --echo End of 5.1 tests