BUG#33429: No check for maxvalue before adding partition

mysql-test/r/partition_range.result

 drop table if exists t1, t2;
+create table t1 (a int)
+partition by range (a)
+( partition p0 values less than (maxvalue));
+alter table t1 add partition (partition p1 values less than (100000));
+ERROR HY000: MAXVALUE can only be used in last partition definition
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` int(11) DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1 /*!50100 PARTITION BY RANGE (a) (PARTITION p0 VALUES LESS THAN MAXVALUE ENGINE = MyISAM) */
+drop table t1;
 create table t1 (a int unsigned)
 partition by range (a)
 (partition pnull values less than (0),

mysql-test/t/partition_range.test

@@ -9,6 +9,17 @@
 drop table if exists t1, t2;
 --enable_warnings
 
+#
+# BUG 33429: Succeeds in  adding partition when maxvalue on last partition
+#
+create table t1 (a int)
+partition by range (a)
+( partition p0 values less than (maxvalue));
+--error ER_PARTITION_MAXVALUE_ERROR
+alter table t1 add partition (partition p1 values less than (100000));
+show create table t1;
+drop table t1;
+
 #
 # BUG 18198: Various tests for partition functions
 #

sql/sql_partition.cc

@@ -4313,7 +4313,12 @@ uint prep_alter_part_table(THD *thd, TABLE *table, Alter_info *alter_info,
       {
         my_error(ER_NO_BINLOG_ERROR, MYF(0));
         DBUG_RETURN(TRUE);
-      } 
+      }
+      if (tab_part_info->defined_max_value)
+      {
+        my_error(ER_PARTITION_MAXVALUE_ERROR, MYF(0));
+        DBUG_RETURN(TRUE);
+      }
       if (no_new_partitions == 0)
       {
         my_error(ER_ADD_PARTITION_NO_NEW_PARTITION, MYF(0));