InnoDB: Failing assertion: result != FTS_INVALID in fts_trx_row_get_new_state

--source include/have_innodb.inc

CREATE TABLE t1 (pk INT PRIMARY KEY, a VARCHAR(1), b VARCHAR(1), KEY (a), FULLTEXT (a)) ENGINE=InnoDB;

INSERT INTO t1 VALUES (1,'i','i'),(2,'i','i');

SET FOREIGN_KEY_CHECKS= OFF;

ALTER TABLE t1 ADD FOREIGN KEY (b) REFERENCES x (xx);

SET FOREIGN_KEY_CHECKS= ON;

ALTER TABLE t1 ADD FOREIGN KEY (a) REFERENCES t1 (b) ON DELETE SET NULL;

START TRANSACTION;

DELETE FROM t1;

# Cleanup

DROP TABLE t1;

2020-09-11 17:08:08 0x7fd544904700  InnoDB: Assertion failure in file /data/src/10.2/storage/innobase/fts/fts0fts.cc line 2218

InnoDB: Failing assertion: result != FTS_INVALID

#6  0x0000561a06103b27 in ut_dbg_assertion_failed (expr=0x561a0677820c "result != FTS_INVALID", file=0x561a06777738 "/data/src/10.2/storage/innobase/fts/fts0fts.cc", line=2218) at /data/src/10.2/storage/innobase/ut/ut0dbg.cc:60

#7  0x0000561a0621e8ef in fts_trx_row_get_new_state (old_state=FTS_DELETE, event=FTS_DELETE) at /data/src/10.2/storage/innobase/fts/fts0fts.cc:2218

#8  0x0000561a0621ed4f in fts_trx_table_add_op (ftt=0x7fd4ec09a010, doc_id=2, state=FTS_DELETE, fts_indexes=0x0) at /data/src/10.2/storage/innobase/fts/fts0fts.cc:2408

#9  0x0000561a0621eea8 in fts_trx_add_op (trx=0x7fd5454d8140, table=0x7fd4ec091f90, doc_id=2, state=FTS_DELETE, fts_indexes=0x0) at /data/src/10.2/storage/innobase/fts/fts0fts.cc:2455

#10 0x0000561a06039147 in row_fts_update_or_delete (prebuilt=0x7fd4ec0a6560) at /data/src/10.2/storage/innobase/row/row0mysql.cc:1677

#11 0x0000561a060398a0 in row_update_for_mysql (prebuilt=0x7fd4ec0a6560) at /data/src/10.2/storage/innobase/row/row0mysql.cc:1857

#12 0x0000561a05efa53d in ha_innobase::delete_row (this=0x7fd4ec098368, record=0x7fd4ec0a01a0 "\375\002") at /data/src/10.2/storage/innobase/handler/ha_innodb.cc:9057

#13 0x0000561a05cfb726 in handler::ha_delete_row (this=0x7fd4ec098368, buf=0x7fd4ec0a01a0 "\375\002") at /data/src/10.2/sql/handler.cc:6168

#14 0x0000561a05e7f6c1 in mysql_delete (thd=0x7fd4ec000d90, table_list=0x7fd4ec0127c0, conds=0x0, order_list=0x7fd4ec005328, limit=18446744073709551614, options=0, result=0x0) at /data/src/10.2/sql/sql_delete.cc:583

#15 0x0000561a05a6ce9c in mysql_execute_command (thd=0x7fd4ec000d90) at /data/src/10.2/sql/sql_parse.cc:4362

#16 0x0000561a05a77a57 in mysql_parse (thd=0x7fd4ec000d90, rawbuf=0x7fd4ec0126f8 "DELETE FROM t1", length=14, parser_state=0x7fd5449035f0, is_com_multi=false, is_next_command=false) at /data/src/10.2/sql/sql_parse.cc:7733

#17 0x0000561a05a65d66 in dispatch_command (command=COM_QUERY, thd=0x7fd4ec000d90, packet=0x7fd4ec008b51 "DELETE FROM t1", packet_length=14, is_com_multi=false, is_next_command=false) at /data/src/10.2/sql/sql_parse.cc:1823

#18 0x0000561a05a64861 in do_command (thd=0x7fd4ec000d90) at /data/src/10.2/sql/sql_parse.cc:1377

#19 0x0000561a05bbe233 in do_handle_one_connection (connect=0x561a0961c660) at /data/src/10.2/sql/sql_connect.cc:1336

#20 0x0000561a05bbdf98 in handle_one_connection (arg=0x561a0961c660) at /data/src/10.2/sql/sql_connect.cc:1241

#21 0x0000561a063e24d2 in pfs_spawn_thread (arg=0x561a09b334a0) at /data/src/10.2/storage/perfschema/pfs.cc:1869

#22 0x00007fd54a9b0609 in start_thread (arg=<optimized out>) at pthread_create.c:477

#23 0x00007fd54a58a103 in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:95