Assertion `inited == NONE || table->open_by_handler' failed in int handler::ha_external_lock(THD *, int)

DELIMITER $$

CREATE FUNCTION f1() RETURNS INT BEGIN EXECUTE IMMEDIATE 'SELECT 1 INTO @x'; RETURN 5; END$$

DELIMITER ;

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

INSERT INTO t1 VALUES (1,2);

CREATE TRIGGER tr1 BEFORE UPDATE ON t1 FOR EACH ROW SET NEW.b = f1();

UPDATE t1 SET a = a + 1;

mariadbd: /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/handler.cc:8014: int handler::ha_external_lock(THD *, int): Assertion `inited == NONE || table->open_by_handler' failed.

Core was generated by `/test/mtest/MDEV-39518/MD020926-mariadb-13.1.0-linux-x86_64-dbg/bin/mariadbd --'.

Program terminated with signal SIGABRT, Aborted.

#0  __pthread_kill_implementation (no_tid=0, signo=6, threadid=<optimized out>)at ./nptl/pthread_kill.c:44

[Current thread is 1 (LWP 2245825)]

(gdb) bt

#0  __pthread_kill_implementation (no_tid=0, signo=6, threadid=<optimized out>)at ./nptl/pthread_kill.c:44

#1  __pthread_kill_internal (signo=6, threadid=<optimized out>)at ./nptl/pthread_kill.c:78

#2  __GI___pthread_kill (threadid=<optimized out>, signo=signo@entry=6)at ./nptl/pthread_kill.c:89

#3  0x00007b40cb64527e in __GI_raise (sig=sig@entry=6)at ../sysdeps/posix/raise.c:26

#4  0x00007b40cb6288ff in __GI_abort () at ./stdlib/abort.c:79

#5  0x00007b40cb62881b in __assert_fail_base (fmt=0x7b40cb7d01e8 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x56626313c64e "inited == NONE || table->open_by_handler", file=file@entry=0x56626313a119 "/test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/handler.cc", line=line@entry=8014, function=function@entry=0x56626313c54c "int handler::ha_external_lock(THD *, int)") at ./assert/assert.c:96

#6  0x00007b40cb63b517 in __assert_fail (assertion=0x56626313c64e "inited == NONE || table->open_by_handler", file=0x56626313a119 "/test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/handler.cc", line=8014, function=0x56626313c54c "int handler::ha_external_lock(THD *, int)")at ./assert/assert.c:105

#7  0x000056626239151e in handler::ha_external_lock (this=0x733f9404cae0, thd=0x733f94000d60, lock_type=2)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/handler.cc:8014

#8  0x0000566261d792e2 in handler::ha_external_unlock (this=0x733f9404cae0, thd=0x733f94000d60)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/handler.h:3773

#9  0x000056626256de83 in unlock_external (thd=0x733f94000d60, table=0x733f9401d620, count=1)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/lock.cc:791

#10 0x000056626256df62 in mysql_unlock_tables (thd=0x733f94000d60, sql_lock=0x733f9401d5f0, free_lock=false)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/lock.cc:482

#11 0x000056626256e11c in mysql_unlock_tables (thd=0x733f94000d60, sql_lock=0x733f9401d5f0)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/lock.cc:465

#12 0x0000566261e3bded in close_thread_tables (thd=0x733f94000d60)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_base.cc:993

#13 0x00005662621ee536 in sp_lex_keeper::reset_lex_and_exec_core (this=0x733f940a0ee0, thd=0x733f94000d60, nextp=0x7b40c80e4fa8, open_tables=true, instr=0x733f940a0ea0, rerun_the_same_instr=false)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sp_instr.cc:438

#14 0x00005662621eebbc in sp_lex_keeper::validate_lex_and_exec_core (this=0x733f940a0ee0, thd=0x733f94000d60, nextp=0x7b40c80e4fa8, open_tables=true, instr=0x733f940a0ea0)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sp_instr.cc:608

#15 0x00005662621f2a3f in sp_instr_set_trigger_field::execute (this=0x733f940a0ea0, thd=0x733f94000d60, nextp=0x7b40c80e4fa8)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sp_instr.cc:1717

#16 0x0000566261dda42c in sp_head::execute (this=0x733f9409f7b0, thd=0x733f94000d60, merge_da_on_success=false)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sp_head.cc:1346

#17 0x0000566261ddc30f in sp_head::execute_trigger (this=0x733f9409f7b0, thd=0x733f94000d60, db_name=0x733f940273c8, table_name=0x733f940273d8, grant_info=0x733f9404dd08)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sp_head.cc:1859

#18 0x00005662620731ac in Table_triggers_list::process_triggers (this=0x733f9404d770, thd=0x733f94000d60, event=TRG_EVENT_UPDATE, time_type=TRG_ACTION_BEFORE, old_row_is_record1=true, skip_row_indicator=0x7b40c80e5cfd, fields_in_update_stmt=0x733f94005e40)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_trigger.cc:2879

#19 0x0000566261e4ec98 in fill_record_n_invoke_before_triggers (thd=0x733f94000d60, table=0x733f94097ba0, fields=@0x733f94005e40: {<base_list> = {<Sql_alloc> = {<No data fields>}, first = 0x733f9401b100, last = 0x733f9401b100, elements = 1}, <No data fields>}, values=@0x733f940062e8: {<base_list> = {<Sql_alloc> = {<No data fields>}, first = 0x733f9401b110, last = 0x733f9401b110, elements = 1}, <No data fields>}, ignore_errors=false, event=TRG_EVENT_UPDATE, skip_row_indicator=0x7b40c80e5cfd)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_base.cc:9674

#20 0x000056626208e453 in Sql_cmd_update::update_single_table (this=0x733f9401b120, thd=0x733f94000d60)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_update.cc:1010

#21 0x0000566262096b67 in Sql_cmd_update::execute_inner (this=0x733f9401b120, thd=0x733f94000d60)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_update.cc:3320

#22 0x0000566261fe02f6 in Sql_cmd_dml::execute (this=0x733f9401b120, thd=0x733f94000d60)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_select.cc:35066

#23 0x0000566261f17ea6 in mysql_execute_command (thd=0x733f94000d60, is_called_from_prepared_stmt=false)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_parse.cc:4484

#24 0x0000566261f0dfd4 in mysql_parse (thd=0x733f94000d60, rawbuf=0x733f9401a490 "UPDATE t1 SET a = a + 1", length=23, parser_state=0x7b40c80e7a80)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_parse.cc:8000

#25 0x0000566261f0b2fd in dispatch_command (command=COM_QUERY, thd=0x733f94000d60, packet=0x733f9400b6c1 "UPDATE t1 SET a = a + 1", packet_length=23, blocking=true)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_parse.cc:1903

#26 0x0000566261f0eb83 in do_command (thd=0x733f94000d60, blocking=true)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_parse.cc:1437

#27 0x0000566262114619 in do_handle_one_connection (connect=0x56629cca6880, put_in_cache=true)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_connect.cc:1514

#28 0x00005662621143be in handle_one_connection (arg=0x56629cc45220)at /test/mtest/MDEV-39518/bb-13.1-bar-MDEV-39518_dbg/sql/sql_connect.cc:1426

#29 0x00007b40cb69cb84 in start_thread (arg=<optimized out>)at ./nptl/pthread_create.c:447

#30 0x00007b40cb729d6c in clone3 ()at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78