Bogus warning ER_TRUNCATED_WRONG_VALUE with DESC key on partitioned Spider table

--source include/have_partition.inc

INSTALL SONAME 'ha_spider';

SET spider_same_server_link= 1;

CREATE TABLE t1 (id INT);

CREATE TABLE t2 (id INT);

eval 

CREATE TABLE t (id INT, PRIMARY KEY (id DESC))

ENGINE=SPIDER

COMMENT "host '127.0.0.1', port '$MASTER_MYPORT', user 'root'"

PARTITION BY RANGE (id)

(PARTITION p1 VALUES LESS THAN (100) COMMENT "table 't1'",

 PARTITION p2 VALUES LESS THAN (MAXVALUE) COMMENT "table 't2'");

INSERT INTO t (id) VALUES (1),(2);

SELECT MAX(id) FROM t;

SELECT MAX(id) FROM t;

MAX(id)

2

Warnings:

Warning	1292	Truncated incorrect INTEGER value: ''