SIGSEGV in Item_trigger_row::cleanup on FLUSH TABLES after a trigger runs DECLARE ROW TYPE OF cursor DEFAULT NEW

CREATE TABLE t1 (a INT);

DELIMITER |

CREATE TRIGGER tr BEFORE INSERT ON t1 FOR EACH ROW BEGIN DECLARE c CURSOR FOR SELECT 1; BEGIN DECLARE r ROW TYPE OF c DEFAULT NEW; END; END|

DELIMITER ;

INSERT INTO t1 VALUES (1);

FLUSH TABLES;

Core was generated by `/test/mtest/MDEV-34723/MD221026-mariadb-13.2.0-linux-x86_64-dbg/bin/mariadbd --'.

Program terminated with signal SIGSEGV, Segmentation fault.

#0  0x00005a9328806c11 in Item_trigger_row::cleanup (this=0x6955500478b0)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/item.h:8069

[Current thread is 1 (LWP 2308066)]

(gdb) bt

#0  0x00005a9328806c11 in Item_trigger_row::cleanup (this=0x6955500478b0)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/item.h:8069

#1  0x00005a93282acc8a in Item::delete_self (this=0x6955500478b0)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/item.h:2700

#2  0x00005a9328624cf0 in sp_instr_cursor_copy_struct::~sp_instr_cursor_copy_struct (this=0x695550047a20)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sp_instr.h:1825

#3  0x00005a9328624d39 in sp_instr_cursor_copy_struct::~sp_instr_cursor_copy_struct (this=0x695550047a20)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sp_instr.h:1823

#4  0x00005a93282018eb in sp_head::~sp_head (this=0x695550035460)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sp_head.cc:925

#5  0x00005a9328202c89 in sp_head::~sp_head (this=0x695550035460)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sp_head.cc:917

#6  0x00005a9328200dbd in sp_head::destroy (sp=0x695550035460)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sp_head.cc:551

#7  0x00005a9328496e59 in Trigger::~Trigger (this=0x69555003bd90)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_trigger.cc:369

#8  0x00005a932849a6c8 in Table_triggers_list::~Table_triggers_list (this=0x69555003b840)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_trigger.cc:1562

#9  0x00005a932869a2ae in intern_close_table (table=0x6955500329f0)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/table_cache.cc:228

#10 0x00005a932869a018 in tc_purge ()at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/table_cache.cc:324

#11 0x00005a932826366e in purge_tables ()at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_base.cc:338

#12 0x00005a9328263831 in close_cached_tables (thd=0x695550000d60, tables=0x0, wait_for_refresh=true, timeout=86400)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_base.cc:367

#13 0x00005a932857fef0 in reload_acl_and_cache (thd=0x695550000d60, options=4, tables=0x0, write_to_binlog=0x71566101ebc4)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_reload.cc:370

#14 0x00005a932834735f in mysql_execute_command (thd=0x695550000d60, is_called_from_prepared_stmt=false)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_parse.cc:5439

#15 0x00005a9328338a84 in mysql_parse (thd=0x695550000d60, rawbuf=0x69555001a4d0 "FLUSH TABLES", length=12, parser_state=0x71566101fa80)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_parse.cc:8005

#16 0x00005a9328335e4d in dispatch_command (command=COM_QUERY, thd=0x695550000d60, packet=0x69555000b701 "FLUSH TABLES", packet_length=12, blocking=true)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_parse.cc:1903

#17 0x00005a9328339633 in do_command (thd=0x695550000d60, blocking=true)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_parse.cc:1437

#18 0x00005a932853fd29 in do_handle_one_connection (connect=0x5a9348d063a0, put_in_cache=true)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_connect.cc:1514

#19 0x00005a932853face in handle_one_connection (arg=0x5a9348defbd0)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_dbg/sql/sql_connect.cc:1426

#20 0x000071568769cb84 in start_thread (arg=<optimized out>)at ./nptl/pthread_create.c:447

#21 0x0000715687729ecc in clone3 ()at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78