SIGSEGV in ha_spider::update_create_info & SIGSEGV in my_hash_insert on ALTER

INSTALL PLUGIN Spider SONAME 'ha_spider.so';

CREATE SERVER srv FOREIGN DATA WRAPPER MYSQL OPTIONS (SOCKET '../socket.sock',DATABASE'',USER'',PASSWORD'');

CREATE TABLE t1 (c1 TIME) ENGINE=Spider PARTITION BY HASH(EXTRACT(HOUR_SECOND FROM c1));

CREATE TABLE t2 (c1 INT) ENGINE=MyISAM;

CREATE TABLE t3 (c1 INT,c2 INT) ENGINE=Spider COMMENT='WRAPPER "mysql",SRV "srv",TABLE "t1"';

INSERT INTO t2 SELECT * FROM t3;

SELECT * FROM t3;

ALTER TABLE t1 CHANGE COLUMN c1 d1 INT;

Core was generated by `/test/MD200724-mariadb-11.2.5-linux-x86_64-dbg/bin/mariadbd --no-defaults --max'.

Program terminated with signal SIGSEGV, Segmentation fault.

#0  ha_spider::update_create_info (this=0x153fe403ab30, create_info=0x1540280e3630)at /test/11.2_dbg/storage/spider/ha_spider.cc:8610

Downloading source file /test/11.2_dbg/storage/spider/ha_spider.cc...

[Current thread is 1 (LWP 1347742)]

(gdb) bt

#0  ha_spider::update_create_info (this=0x153fe403ab30, create_info=0x1540280e3630)at /test/11.2_dbg/storage/spider/ha_spider.cc:8610

#1  0x000055e0629d05d8 in ha_partition::update_create_info (this=0x153fe403a250, create_info=<optimized out>)at /test/11.2_dbg/sql/ha_partition.cc:2372

#2  0x000055e062504368 in mysql_prepare_alter_table (thd=thd@entry=0x153fe8000d58, table=table@entry=0x153fe40399e8, create_info=create_info@entry=0x1540280e6340, alter_info=alter_info@entry=0x1540280e61d0, alter_ctx=alter_ctx@entry=0x1540280e54b0)at /test/11.2_dbg/sql/sql_table.cc:9237

#3  0x000055e062512cec in mysql_alter_table (thd=thd@entry=0x153fe8000d58, new_db=<optimized out>, new_name=new_name@entry=0x153fe8005fd8, create_info=create_info@entry=0x1540280e6340, table_list=<optimized out>, table_list@entry=0x153fe8013738, recreate_info=recreate_info@entry=0x1540280e6190, alter_info=<optimized out>, order_num=<optimized out>, order=<optimized out>, ignore=<optimized out>, if_exists=<optimized out>)at /test/11.2_dbg/sql/sql_table.cc:10878

#4  0x000055e06259b609 in Sql_cmd_alter_table::execute (this=<optimized out>, thd=0x153fe8000d58) at /test/11.2_dbg/sql/sql_alter.cc:701

#5  0x000055e062425db3 in mysql_execute_command (thd=thd@entry=0x153fe8000d58, is_called_from_prepared_stmt=is_called_from_prepared_stmt@entry=false)at /test/11.2_dbg/sql/sql_parse.cc:5876

#6  0x000055e062427753 in mysql_parse (thd=thd@entry=0x153fe8000d58, rawbuf=<optimized out>, length=<optimized out>, parser_state=parser_state@entry=0x1540280e72e0)at /test/11.2_dbg/sql/sql_parse.cc:7920

#7  0x000055e062429ada in dispatch_command (command=command@entry=COM_QUERY, thd=thd@entry=0x153fe8000d58, packet=packet@entry=0x153fe800b309 "ALTER TABLE t1 CHANGE COLUMN c1 d1 INT", packet_length=packet_length@entry=38, blocking=blocking@entry=true)at /test/11.2_dbg/sql/sql_class.h:247

#8  0x000055e06242bdff in do_command (thd=0x153fe8000d58, blocking=blocking@entry=true) at /test/11.2_dbg/sql/sql_parse.cc:1407

#9  0x000055e062592e61 in do_handle_one_connection (connect=<optimized out>, connect@entry=0x55e064df09a8, put_in_cache=put_in_cache@entry=true)at /test/11.2_dbg/sql/sql_connect.cc:1439

#10 0x000055e062593156 in handle_one_connection (arg=arg@entry=0x55e064df09a8)at /test/11.2_dbg/sql/sql_connect.cc:1341

#11 0x000055e0629e4192 in pfs_spawn_thread (arg=0x55e064dbfb68)at /test/11.2_dbg/storage/perfschema/pfs.cc:2201

#12 0x0000154031c97ada in start_thread (arg=<optimized out>)at ./nptl/pthread_create.c:444

#13 0x0000154031d2847c in clone3 ()at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78