Instant operation fails when add column and collation change on non-indexed column

--source include/have_innodb.inc

CREATE TABLE t1 (a CHAR) ENGINE=InnoDB;

ALTER TABLE t1 DEFAULT COLLATE = latin1_general_cs;

ALTER TABLE t1 ADD b INT NOT NULL, MODIFY a CHAR, ALGORITHM=INSTANT;

# Cleanup

DROP TABLE t1;

mysqld: /data/src/10.4/storage/innobase/handler/handler0alter.cc:539: bool dict_table_t::instant_column(const dict_table_t&, const ulint*): Assertion `!((c.prtype ^ o->prtype) & ~(256U | (16384U|32768U) | 4096U))' failed.

190727 15:17:50 [ERROR] mysqld got signal 6 ;

#7  0x00007f0887c24f12 in __GI___assert_fail (assertion=0x560a812749d8 "!((c.prtype ^ o->prtype) & ~(256U | (16384U|32768U) | 4096U))", file=0x560a81273f38 "/data/src/10.4/storage/innobase/handler/handler0alter.cc", line=539, function=0x560a8127b800 <dict_table_t::instant_column(dict_table_t const&, unsigned long const*)::__PRETTY_FUNCTION__> "bool dict_table_t::instant_column(const dict_table_t&, const ulint*)") at assert.c:101

#8  0x0000560a80a347a7 in dict_table_t::instant_column (this=0x7f083800ac38, table=..., col_map=0x7f0838142330) at /data/src/10.4/storage/innobase/handler/handler0alter.cc:537

#9  0x0000560a80a374cc in ha_innobase_inplace_ctx::instant_column (this=0x7f08380148d8) at /data/src/10.4/storage/innobase/handler/handler0alter.cc:1080

#10 0x0000560a80a1c10f in innobase_instant_try (ha_alter_info=0x7f0880ff17c0, ctx=0x7f08380148d8, altered_table=0x7f0880ff1850, table=0x7f0838151630, trx=0x7f0881a8f268) at /data/src/10.4/storage/innobase/handler/handler0alter.cc:5645

#11 0x0000560a80a3a2e3 in commit_try_norebuild (ha_alter_info=0x7f0880ff17c0, ctx=0x7f08380148d8, altered_table=0x7f0880ff1850, old_table=0x7f0838151630, trx=0x7f0881a8f268, table_name=0x7f083800be8d "t1") at /data/src/10.4/storage/innobase/handler/handler0alter.cc:10170

#12 0x0000560a80a2c04d in ha_innobase::commit_inplace_alter_table (this=0x7f0838152498, altered_table=0x7f0880ff1850, ha_alter_info=0x7f0880ff17c0, commit=true) at /data/src/10.4/storage/innobase/handler/handler0alter.cc:10924

#13 0x0000560a807bdc8e in handler::ha_commit_inplace_alter_table (this=0x7f0838152498, altered_table=0x7f0880ff1850, ha_alter_info=0x7f0880ff17c0, commit=true) at /data/src/10.4/sql/handler.cc:4575

#14 0x0000560a8055a278 in mysql_inplace_alter_table (thd=0x7f0838000b00, table_list=0x7f0838013250, table=0x7f0838151630, altered_table=0x7f0880ff1850, ha_alter_info=0x7f0880ff17c0, inplace_supported=HA_ALTER_INPLACE_INSTANT, target_mdl_request=0x7f0880ff2620, alter_ctx=0x7f0880ff3150) at /data/src/10.4/sql/sql_table.cc:7718

#15 0x0000560a80560b25 in mysql_alter_table (thd=0x7f0838000b00, new_db=0x7f08380052b0, new_name=0x7f08380056b8, create_info=0x7f0880ff3d30, table_list=0x7f0838013250, alter_info=0x7f0880ff3c70, order_num=0, order=0x0, ignore=false) at /data/src/10.4/sql/sql_table.cc:10029

#16 0x0000560a805f2413 in Sql_cmd_alter_table::execute (this=0x7f0838013b48, thd=0x7f0838000b00) at /data/src/10.4/sql/sql_alter.cc:508

#17 0x0000560a804800e5 in mysql_execute_command (thd=0x7f0838000b00) at /data/src/10.4/sql/sql_parse.cc:6098

#18 0x0000560a80485355 in mysql_parse (thd=0x7f0838000b00, rawbuf=0x7f0838013118 "ALTER TABLE t1 ADD b INT NOT NULL, MODIFY a CHAR, ALGORITHM=INSTANT", length=67, parser_state=0x7f0880ff5180, is_com_multi=false, is_next_command=false) at /data/src/10.4/sql/sql_parse.cc:7908

#19 0x0000560a804715fe in dispatch_command (command=COM_QUERY, thd=0x7f0838000b00, packet=0x7f083819df71 "ALTER TABLE t1 ADD b INT NOT NULL, MODIFY a CHAR, ALGORITHM=INSTANT", packet_length=67, is_com_multi=false, is_next_command=false) at /data/src/10.4/sql/sql_parse.cc:1843

#20 0x0000560a8046fd44 in do_command (thd=0x7f0838000b00) at /data/src/10.4/sql/sql_parse.cc:1360

#21 0x0000560a805e9282 in do_handle_one_connection (connect=0x560a83c06950) at /data/src/10.4/sql/sql_connect.cc:1404

#22 0x0000560a805e8fd1 in handle_one_connection (arg=0x560a83c06950) at /data/src/10.4/sql/sql_connect.cc:1306

#23 0x0000560a80f1496f in pfs_spawn_thread (arg=0x560a83b852d0) at /data/src/10.4/storage/perfschema/pfs.cc:1862

#24 0x00007f08897994a4 in start_thread (arg=0x7f0880ff6700) at pthread_create.c:456

#25 0x00007f0887ce1d0f in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:97