MDEV-27072 Subquery using the ALL keyword on date columns produces a wrong result

mysql-test/r/type_date.result

@@ -932,5 +932,17 @@ Warning	1292	Incorrect datetime value: '1995.0000000'
 Note	1003	select `test`.`t1`.`f` AS `f` from `test`.`t1` where '0000-00-00' between `test`.`t1`.`f` and <cache>('2012-12-12')
 DROP TABLE t1;
 #
+# MDEV-27072 Subquery using the ALL keyword on date columns produces a wrong result
+#
+CREATE TABLE t1 (d DATE);
+INSERT INTO t1 VALUES ('2021-11-17'), ('2021-10-17'),('2022-11-17'), ('2020-10-17');
+SELECT * FROM t1 WHERE d >= ALL (SELECT * FROM t1);
+d
+2022-11-17
+SELECT * FROM t1 WHERE d <= ALL (SELECT * FROM t1);
+d
+2020-10-17
+DROP TABLE t1;
+#
 # End of 10.2 tests
 #

mysql-test/t/type_date.test

@@ -647,6 +647,15 @@ INSERT INTO t1 VALUES ('2020-01-01'),('2020-01-02');
 EXPLAIN EXTENDED SELECT * FROM t1 WHERE 1995.0000000 BETWEEN f AND '2012-12-12';
 DROP TABLE t1;
 
+--echo #
+--echo # MDEV-27072 Subquery using the ALL keyword on date columns produces a wrong result
+--echo #
+
+CREATE TABLE t1 (d DATE);
+INSERT INTO t1 VALUES ('2021-11-17'), ('2021-10-17'),('2022-11-17'), ('2020-10-17');
+SELECT * FROM t1 WHERE d >= ALL (SELECT * FROM t1);
+SELECT * FROM t1 WHERE d <= ALL (SELECT * FROM t1);
+DROP TABLE t1;
 
 --echo #
 --echo # End of 10.2 tests

sql/sql_class.cc

@@ -3479,7 +3479,7 @@ bool select_max_min_finder_subselect::cmp_str()
     but added for safety
   */
   val1= cache->val_str(&buf1);
-  val2= maxmin->val_str(&buf1);
+  val2= maxmin->val_str(&buf2);
 
   /* Ignore NULLs for ANY and keep them for ALL subqueries */
   if (cache->null_value)