SIGSEGV in Field_iterator_table::set_table on re-prepare of trigger SET NEW = (subquery) after DDL on referenced table

CREATE TABLE t1 (a INT, b INT);

CREATE TABLE t2 (a INT, b INT);

CREATE TRIGGER tr BEFORE INSERT ON t2 FOR EACH ROW SET NEW = (SELECT a,b FROM t1);

INSERT INTO t2 VALUES (1,1);

ALTER TABLE t1 FORCE;

INSERT INTO t2 VALUES (2,2);  

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

Program terminated with signal SIGSEGV, Segmentation fault.

#0  Field_iterator_table::set_table (table=0x0, this=<optimized out>)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/table.h:3360

[Current thread is 1 (LWP 1366660)]

(gdb) bt

#0  Field_iterator_table::set_table (table=0x0, this=<optimized out>)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/table.h:3360

#1  Item_trigger_row::populate_with_trigger_fields (this=this@entry=0x6bdc2c077d90, thd=thd@entry=0x6bdc2c000c70)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/item.cc:11167

#2  0x000063ab5125a465 in Item_trigger_row::fix_fields (this=0x6bdc2c077d90, thd=0x6bdc2c000c70, it=<optimized out>)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/item.cc:11134

#3  0x000063ab5125a780 in Item::fix_fields_if_needed (this=0x6bdc2c077d90, thd=0x6bdc2c000c70, ref=0x0)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/item.h:1153

#4  Item_trigger_row::set_value (this=0x6bdc2c077d90, thd=0x6bdc2c000c70, ctx=<optimized out>, it=0x6bdc2c02a2e8)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/item.cc:11199

#5  0x000063ab5115a0d9 in sp_instr_set_trigger_row::exec_core (this=0x6bdc2c02a210, thd=0x6bdc2c000c70, nextp=0x73dd44406554)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sp_instr.cc:1777

#6  0x000063ab5115738a in sp_lex_keeper::reset_lex_and_exec_core (this=this@entry=0x6bdc2c02a248, thd=thd@entry=0x6bdc2c000c70, nextp=nextp@entry=0x73dd44406554, open_tables=true, instr=instr@entry=0x6bdc2c02a210, rerun_the_same_instr=<optimized out>)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sp_instr.cc:420

#7  0x000063ab511579b6 in sp_lex_keeper::validate_lex_and_exec_core (this=0x6bdc2c02a248, thd=0x6bdc2c000c70, nextp=0x73dd44406554, open_tables=<optimized out>, instr=0x6bdc2c02a210)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sp_instr.cc:624

#8  0x000063ab50f005aa in sp_head::execute (this=this@entry=0x6bdc2c028470, thd=thd@entry=0x6bdc2c000c70, merge_da_on_success=false)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sp_head.cc:1347

#9  0x000063ab50f01642 in sp_head::execute_trigger (this=0x6bdc2c028470, thd=0x6bdc2c000c70, db_name=<optimized out>, table_name=<optimized out>, grant_info=<optimized out>)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sp_head.cc:1863

#10 0x000063ab5107ad86 in Table_triggers_list::process_triggers (this=0x6bdc2c033f80, thd=0x6bdc2c000c70, event=TRG_EVENT_INSERT, time_type=<optimized out>, old_row_is_record1=<optimized out>, skip_row_indicator=0x73dd44406f08, fields_in_update_stmt=0x0)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sql_trigger.cc:2918

#11 0x000063ab50f42401 in fill_record_n_invoke_before_triggers (thd=thd@entry=0x6bdc2c000c70, table=0x6bdc2c022780, ptr=0x6bdc2c033ba0, values=@0x6bdc2c0189e0: {<base_list> = {<Sql_alloc> = {<No data fields>}, first = 0x6bdc2c018aa0, last = 0x6bdc2c018b50, elements = 2}, <No data fields>}, ignore_errors=<optimized out>, event=event@entry=TRG_EVENT_INSERT, skip_row_indicator=0x73dd44406f08)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sql_base.cc:9946

#12 0x000063ab50f710ff in mysql_insert (thd=thd@entry=0x6bdc2c000c70, table_list=0x6bdc2c017d80, fields=@0x6bdc2c006208: {<base_list> = {<Sql_alloc> = {<No data fields>}, first = 0x63ab522a63c8 <end_of_list>, last = 0x6bdc2c006208, elements = 0}, <No data fields>}, values_list=@0x6bdc2c006250: {<base_list> = {<Sql_alloc> = {<No data fields>}, first = 0x6bdc2c018b60, last = 0x6bdc2c018b60, elements = 1}, <No data fields>}, update_fields=@0x6bdc2c006238: {<base_list> = {<Sql_alloc> = {<No data fields>}, first = 0x63ab522a63c8 <end_of_list>, last = 0x6bdc2c006238, elements = 0}, <No data fields>}, update_values=@0x6bdc2c006220: {<base_list> = {<Sql_alloc> = {<No data fields>}, first = 0x63ab522a63c8 <end_of_list>, last = 0x6bdc2c006220, elements = 0}, <No data fields>}, duplic=DUP_ERROR, ignore=<optimized out>, result=0x0)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sql_insert.cc:1193

#13 0x000063ab50fb1f66 in mysql_execute_command (thd=thd@entry=0x6bdc2c000c70, is_called_from_prepared_stmt=false)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sql_parse.cc:4549

#14 0x000063ab50faa8e2 in mysql_parse (thd=thd@entry=0x6bdc2c000c70, rawbuf=<optimized out>, length=<optimized out>, parser_state=parser_state@entry=0x73dd44407580)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sql_parse.cc:8005

#15 0x000063ab50fa8e98 in dispatch_command (command=command@entry=COM_QUERY, thd=thd@entry=0x6bdc2c000c70, packet=packet@entry=0x6bdc2c008ea1 "INSERT INTO t2 VALUES (2,2)", packet_length=packet_length@entry=27, blocking=true)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sql_parse.cc:1903

#16 0x000063ab50faad61 in do_command (thd=thd@entry=0x6bdc2c000c70, blocking=true)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sql_parse.cc:1437

#17 0x000063ab510d79bd in do_handle_one_connection (connect=<optimized out>, connect@entry=0x63ab7544cd80, put_in_cache=true)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sql_connect.cc:1514

#18 0x000063ab510d77f2 in handle_one_connection (arg=arg@entry=0x63ab7544cd80)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/sql/sql_connect.cc:1426

#19 0x000063ab51485d83 in pfs_spawn_thread (arg=0x63ab7546d770)at /test/mtest/MDEV-34723/bb-MDEV-34723-rucha_opt/storage/perfschema/pfs.cc:2198

#20 0x000073dd4609cb84 in start_thread (arg=<optimized out>)at ./nptl/pthread_create.c:447

#21 0x000073dd46129ecc in clone3 ()at ../sysdeps/unix/sysv/linux/x86_64/clone3.S:78