Assertion fails in Item_exists_subselect::exists2in_processor upon concurrent 2nd PS execution and DML

CREATE TABLE t1 (a INT, b VARCHAR(1)) ENGINE=MyISAM;

INSERT INTO t1 VALUES (1,NULL),(2,'y');

CREATE TABLE t2 (c INT) ENGINE=MyISAM;

INSERT INTO t2 VALUES (3),(4);

CREATE TABLE t3 (d INT, e VARCHAR(1)) ENGINE=MyISAM;

INSERT INTO t3 VALUES (5,NULL),(6,'y');

--connect (con1,localhost,root,,)

SET lock_wait_timeout= 0;

--let $run=10000

while ($run)

{

  --connection default

  --send

    UPDATE t3 JOIN t1 SET d = d+1;

  --connection con1

  PREPARE stmt FROM 'UPDATE t1 JOIN t2 SET t1.a = 1 WHERE EXISTS (SELECT 1 FROM t3 WHERE e = t1.b)';

  --error 0,ER_LOCK_WAIT_TIMEOUT

  EXECUTE stmt;

  --error 0,ER_LOCK_WAIT_TIMEOUT

  EXECUTE stmt;

  --connection default

  --reap

  --dec $run

}

DROP TABLE t1, t2, t3;

mariadbd: /data/bld/10.5-asan/sql/item_subselect.cc:3246: virtual bool Item_exists_subselect::exists2in_processor(void*): Assertion `thd->stmt_arena->is_stmt_prepare_or_first_stmt_execute() || thd->stmt_arena->is_conventional()' failed.

241013  1:20:22 [ERROR] mysqld got signal 6 ;

#9  0x00007f1ee4053e32 in __GI___assert_fail (assertion=0x557c5ccac0e0 "thd->stmt_arena->is_stmt_prepare_or_first_stmt_execute() || thd->stmt_arena->is_conventional()", file=0x557c5cca8b40 "/data/bld/11.6-asan/sql/item_subselect.cc", line=3338, function=0x557c5ccabe60 "virtual bool Item_exists_subselect::exists2in_processor(void*)") at ./assert/assert.c:101

#10 0x0000557c5afaf35e in Item_exists_subselect::exists2in_processor (this=0x62d00089d650, opt_arg=0x62c0000f0218) at /data/bld/11.6-asan/sql/item_subselect.cc:3338

#11 0x0000557c5af92856 in Item_subselect::walk (this=0x62d00089d650, processor=&virtual table offset 1048, walk_subquery=false, argument=0x62c0000f0218) at /data/bld/11.6-asan/sql/item_subselect.cc:782

#12 0x0000557c5adc5823 in Item_in_optimizer::walk (this=0x62d00089da70, processor=&virtual table offset 1048, walk_subquery=false, arg=0x62c0000f0218) at /data/bld/11.6-asan/sql/item_cmpfunc.cc:1543

#13 0x0000557c5a46ad5a in JOIN::optimize_inner (this=0x629000276550) at /data/bld/11.6-asan/sql/sql_select.cc:2237

#14 0x0000557c5a468b4b in JOIN::optimize (this=0x629000276550) at /data/bld/11.6-asan/sql/sql_select.cc:2003

#15 0x0000557c5a5586e7 in Sql_cmd_dml::execute_inner (this=0x62d00089bbd0, thd=0x62c0000f0218) at /data/bld/11.6-asan/sql/sql_select.cc:34312

#16 0x0000557c5a7231b0 in Sql_cmd_update::execute_inner (this=0x62d00089bbd0, thd=0x62c0000f0218) at /data/bld/11.6-asan/sql/sql_update.cc:3115

#17 0x0000557c5a55838c in Sql_cmd_dml::execute (this=0x62d00089bbd0, thd=0x62c0000f0218) at /data/bld/11.6-asan/sql/sql_select.cc:34261

#18 0x0000557c5a36f1aa in mysql_execute_command (thd=0x62c0000f0218, is_called_from_prepared_stmt=true) at /data/bld/11.6-asan/sql/sql_parse.cc:4403

#19 0x0000557c5a41b3e6 in Prepared_statement::execute (this=0x619000133d98, expanded_query=0x7f1ed76a15b0, open_cursor=false) at /data/bld/11.6-asan/sql/sql_prepare.cc:5050

#20 0x0000557c5a416349 in Prepared_statement::execute_loop (this=0x619000133d98, expanded_query=0x7f1ed76a15b0, open_cursor=false, packet=0x0, packet_end=0x0) at /data/bld/11.6-asan/sql/sql_prepare.cc:4427

#21 0x0000557c5a40f802 in mysql_sql_stmt_execute (thd=0x62c0000f0218) at /data/bld/11.6-asan/sql/sql_prepare.cc:3446

#22 0x0000557c5a36c833 in mysql_execute_command (thd=0x62c0000f0218, is_called_from_prepared_stmt=false) at /data/bld/11.6-asan/sql/sql_parse.cc:3970

#23 0x0000557c5a3874f4 in mysql_parse (thd=0x62c0000f0218, rawbuf=0x629000276238 "EXECUTE stmt", length=12, parser_state=0x7f1ed76a29f0) at /data/bld/11.6-asan/sql/sql_parse.cc:7885

#24 0x0000557c5a35e630 in dispatch_command (command=COM_QUERY, thd=0x62c0000f0218, packet=0x62900026c219 "EXECUTE stmt", packet_length=12, blocking=true) at /data/bld/11.6-asan/sql/sql_parse.cc:1892

#25 0x0000557c5a35b344 in do_command (thd=0x62c0000f0218, blocking=true) at /data/bld/11.6-asan/sql/sql_parse.cc:1405

#26 0x0000557c5a848f80 in do_handle_one_connection (connect=0x6080000036b8, put_in_cache=true) at /data/bld/11.6-asan/sql/sql_connect.cc:1448

#27 0x0000557c5a84893c in handle_one_connection (arg=0x6080000036b8) at /data/bld/11.6-asan/sql/sql_connect.cc:1350

#28 0x0000557c5b4d286c in pfs_spawn_thread (arg=0x617000005f18) at /data/bld/11.6-asan/storage/perfschema/pfs.cc:2198

#29 0x00007f1ee40a8044 in start_thread (arg=<optimized out>) at ./nptl/pthread_create.c:442

#30 0x00007f1ee412861c in clone3 () at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:81