Assertion `*nulls < null_mask' failed in rec_convert_dtuple_to_rec_comp

--source include/have_innodb.inc

SELECT * FROM information_schema.columns WHERE table_name = 'DUMMY';

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

CREATE TABLE t1 (a CHAR NULL, g GEOMETRY NOT NULL /*!100201 DEFAULT ST_GEOMFROMTEXT('Point(1 1)') */, i TINYINT NOT NULL DEFAULT 0) ENGINE=InnoDB;

ALTER TABLE t1 MODIFY a DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP FIRST ;

ALTER TABLE t1 MODIFY a DATETIME NULL DEFAULT '2000-01-01 00:00:00' FIRST ;

--connection default

INSERT INTO t1 (a) VALUES ( NOW() );

# Cleanup

--disconnect con1

--connection default

DROP TABLE t1;

mysqld: /data/src/bb-10.4-MDEV-17520/storage/innobase/rem/rem0rec.cc:1622: void rec_convert_dtuple_to_rec_comp(rec_t*, const dict_index_t*, const dfield_t*, ulint, rec_comp_status_t, bool) [with bool mblob = false; rec_t = unsigned char; ulint = long unsigned int]: Assertion `*nulls < null_mask' failed.

181204 11:37:34 [ERROR] mysqld got signal 6 ;

#7  0x00007fd015fceee2 in __assert_fail () from /lib/x86_64-linux-gnu/libc.so.6

#8  0x00005632888f07fb in rec_convert_dtuple_to_rec_comp<false> (rec=0x7fcfa40086fe "", index=0x7fcfa803dbe8, field=0x7fcfa4042338, n_fields=6, status=REC_STATUS_ORDINARY, temp=false) at /data/src/bb-10.4-MDEV-17520/storage/innobase/rem/rem0rec.cc:1622

#9  0x00005632888e8bca in rec_convert_dtuple_to_rec_new (buf=0x7fcfa40086fe "", index=0x7fcfa803dbe8, dtuple=0x7fcfa40422a8) at /data/src/bb-10.4-MDEV-17520/storage/innobase/rem/rem0rec.cc:1730

#10 0x00005632888e8cdf in rec_convert_dtuple_to_rec (buf=0x7fcfa40086f8 "\217\217", format=REC_FMT_LEAF, index=0x7fcfa803dbe8, dtuple=0x7fcfa40422a8, n_ext=0) at /data/src/bb-10.4-MDEV-17520/storage/innobase/rem/rem0rec.cc:1756

#11 0x0000563288a2035f in page_cur_tuple_insert (cursor=0x7fd00b307ad8, tuple=0x7fcfa40422a8, index=0x7fcfa803dbe8, offsets=0x7fd00b307a68, heap=0x7fd00b307a60, n_ext=0, mtr=0x7fd00b307ef0) at /data/src/bb-10.4-MDEV-17520/storage/innobase/include/page0cur.ic:282

#12 0x0000563288a2c0dc in btr_cur_optimistic_insert (flags=0, cursor=0x7fd00b307ad0, offsets=0x7fd00b307a68, heap=0x7fd00b307a60, entry=0x7fcfa40422a8, rec=0x7fd00b307a70, big_rec=0x7fd00b307a58, n_ext=0, thr=0x7fcfa80466d8, mtr=0x7fd00b307ef0) at /data/src/bb-10.4-MDEV-17520/storage/innobase/btr/btr0cur.cc:3513

#13 0x0000563288913540 in row_ins_clust_index_entry_low (flags=0, mode=2, index=0x7fcfa803dbe8, n_uniq=0, entry=0x7fcfa40422a8, n_ext=0, thr=0x7fcfa80466d8, dup_chk_only=false) at /data/src/bb-10.4-MDEV-17520/storage/innobase/row/row0ins.cc:2756

#14 0x0000563288914d14 in row_ins_clust_index_entry (index=0x7fcfa803dbe8, entry=0x7fcfa40422a8, thr=0x7fcfa80466d8, n_ext=0, dup_chk_only=false) at /data/src/bb-10.4-MDEV-17520/storage/innobase/row/row0ins.cc:3262

#15 0x00005632889151ca in row_ins_index_entry (index=0x7fcfa803dbe8, entry=0x7fcfa40422a8, thr=0x7fcfa80466d8) at /data/src/bb-10.4-MDEV-17520/storage/innobase/row/row0ins.cc:3387

#16 0x00005632889158a0 in row_ins_index_entry_step (node=0x7fcfa8046440, thr=0x7fcfa80466d8) at /data/src/bb-10.4-MDEV-17520/storage/innobase/row/row0ins.cc:3555

#17 0x0000563288915cd4 in row_ins (node=0x7fcfa8046440, thr=0x7fcfa80466d8) at /data/src/bb-10.4-MDEV-17520/storage/innobase/row/row0ins.cc:3698

#18 0x00005632889164d4 in row_ins_step (thr=0x7fcfa80466d8) at /data/src/bb-10.4-MDEV-17520/storage/innobase/row/row0ins.cc:3943

#19 0x0000563288935fcf in row_insert_for_mysql (mysql_rec=0x7fcfa8044790 "\376\231\241\210\271b\031", prebuilt=0x7fcfa8045ec8, ins_mode=ROW_INS_NORMAL) at /data/src/bb-10.4-MDEV-17520/storage/innobase/row/row0mysql.cc:1460

#20 0x00005632887cf830 in ha_innobase::write_row (this=0x7fcfa8044be8, record=0x7fcfa8044790 "\376\231\241\210\271b\031") at /data/src/bb-10.4-MDEV-17520/storage/innobase/handler/ha_innodb.cc:8045

#21 0x00005632884af6cc in handler::ha_write_row (this=0x7fcfa8044be8, buf=0x7fcfa8044790 "\376\231\241\210\271b\031") at /data/src/bb-10.4-MDEV-17520/sql/handler.cc:6238

#22 0x0000563288154a9b in write_record (thd=0x7fcfa4000b00, table=0x7fcfa8043b50, info=0x7fd00b308b80) at /data/src/bb-10.4-MDEV-17520/sql/sql_insert.cc:2022

#23 0x0000563288151e27 in mysql_insert (thd=0x7fcfa4000b00, table_list=0x7fcfa4014ea0, fields=..., values_list=..., update_fields=..., update_values=..., duplic=DUP_ERROR, ignore=false) at /data/src/bb-10.4-MDEV-17520/sql/sql_insert.cc:1063

#24 0x000056328819822f in mysql_execute_command (thd=0x7fcfa4000b00) at /data/src/bb-10.4-MDEV-17520/sql/sql_parse.cc:4732

#25 0x00005632881a2dee in mysql_parse (thd=0x7fcfa4000b00, rawbuf=0x7fcfa4014da8 "INSERT INTO t1 (a) VALUES ( NOW() )", length=35, parser_state=0x7fd00b309600, is_com_multi=false, is_next_command=false) at /data/src/bb-10.4-MDEV-17520/sql/sql_parse.cc:8092

#26 0x00005632881900dc in dispatch_command (command=COM_QUERY, thd=0x7fcfa4000b00, packet=0x7fcfa400b411 "INSERT INTO t1 (a) VALUES ( NOW() )", packet_length=35, is_com_multi=false, is_next_command=false) at /data/src/bb-10.4-MDEV-17520/sql/sql_parse.cc:1851

#27 0x000056328818eb00 in do_command (thd=0x7fcfa4000b00) at /data/src/bb-10.4-MDEV-17520/sql/sql_parse.cc:1396

#28 0x00005632882fa1ce in do_handle_one_connection (connect=0x56328aeac840) at /data/src/bb-10.4-MDEV-17520/sql/sql_connect.cc:1402

#29 0x00005632882f9f52 in handle_one_connection (arg=0x56328aeac840) at /data/src/bb-10.4-MDEV-17520/sql/sql_connect.cc:1308

#30 0x00005632887ae41c in pfs_spawn_thread (arg=0x56328af31bc0) at /data/src/bb-10.4-MDEV-17520/storage/perfschema/pfs.cc:1862

#31 0x00007fd017a8a494 in start_thread (arg=0x7fd00b30a700) at pthread_create.c:333

#32 0x00007fd01608b93f in clone () from /lib/x86_64-linux-gnu/libc.so.6