Server crashes in copy_data_between_tables or Assertion `thd->transaction.stmt.is_empty() || (thd->state_flags & Open_tables_state::BACKUPS_AVAIL)' fails in close_tables_for_reopen upon concurrent ALTER TABLE and FLUSH

--source include/have_innodb.inc

CREATE TABLE t1 (pk INT PRIMARY KEY, c INT) ENGINE=InnoDB;

CREATE TABLE t2 (pk INT PRIMARY KEY) ENGINE=InnoDB;

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

ALTER TABLE t1 DROP COLUMN IF EXISTS f;

--send

  ALTER TABLE t1 ADD FOREIGN KEY (c) REFERENCES t2 (pk);

--connection default

FLUSH TABLES;

# Cleanup

--connection con1

--reap

--disconnect con1

--connection default

DROP TABLE t1, t2;

#3  0x0000000000000000 in ?? ()

#4  0x00000000006ddafa in Copy_field::set (this=0x7f688c01feb8, to=0x7f688c02f458, from=0x7f688c02e458, save=<optimized out>) at /data/src/10.0/sql/field_conv.cc:644

#5  0x00000000005126cb in copy_data_between_tables (thd=0x7f6893f9d008, from=0x7f688c02f458, to=0x7f688c0d2008, create=..., ignore=56, order_num=182, order=0x0, copied=0x7f688c05f808, deleted=0x7f688c05f808, keys_onoff=Alter_info::LEAVE_AS_IS, alter_ctx=0x7f68a126e6d0) at /data/src/10.0/sql/sql_table.cc:9551

#6  0x0000000000622578 in mysql_alter_table (thd=0x7f6893f9d008, new_db=0x7f688c10d020 "", new_name=0x7f6893fa07a0 "\360\225\260", create_info=0x7f688c0d2008, table_list=0x7f688c01e138, alter_info=0xb6, order_num=0, order=0x0, ignore=false) at /data/src/10.0/sql/sql_table.cc:9150

#7  0x000000000065ff8d in Sql_cmd_alter_table::execute (this=0x7f688c02e458, thd=0x7f6893f9d008) at /data/src/10.0/sql/sql_alter.cc:312

#8  0x00000000005a5431 in mysql_execute_command (thd=0x7f6893f9d008) at /data/src/10.0/sql/sql_parse.cc:5118

#9  0x00000000005aba68 in mysql_parse (thd=0x7f6893f9d008, rawbuf=<optimized out>, length=53, parser_state=0x7f68a1270850) at /data/src/10.0/sql/sql_parse.cc:6637

#10 0x00000000005ad414 in dispatch_command (command=<optimized out>, thd=0x7f6893f9d008, packet=<optimized out>, packet_length=<optimized out>) at /data/src/10.0/sql/sql_parse.cc:1300

#11 0x00000000005add7f in do_command (thd=<optimized out>) at /data/src/10.0/sql/sql_parse.cc:1003

#12 0x000000000065d6d4 in do_handle_one_connection (thd_arg=thd_arg@entry=0x7f6893f9d008) at /data/src/10.0/sql/sql_connect.cc:1377

#13 0x000000000065d718 in handle_one_connection (arg=arg@entry=0x7f6893f9d008) at /data/src/10.0/sql/sql_connect.cc:1292

#14 0x0000000000891f14 in pfs_spawn_thread (arg=0x7f689e83fc08) at /data/src/10.0/storage/perfschema/pfs.cc:1861

#15 0x00007f68a0ef6494 in start_thread (arg=0x7f68a1271700) at pthread_create.c:333

#16 0x00007f689f4ca93f in clone () from /lib/x86_64-linux-gnu/libc.so.6

mysqld: /data/src/10.0/sql/sql_base.cc:5673: void close_tables_for_reopen(THD*, TABLE_LIST**, const MDL_savepoint&): Assertion `thd->transaction.stmt.is_empty() || (thd->state_flags & Open_tables_state::BACKUPS_AVAIL)' failed.

181101 21:39:48 [ERROR] mysqld got signal 6 ;

#7  0x00007fca51305ee2 in __assert_fail () from /lib/x86_64-linux-gnu/libc.so.6

#8  0x00000000005f1ed1 in close_tables_for_reopen (thd=0x7fca4576f070, tables=0x7fca3d4221a8, start_of_statement_svp=...) at /data/src/10.0/sql/sql_base.cc:5672

#9  0x00000000005effb2 in open_tables (thd=0x7fca4576f070, start=0x7fca3d4221a8, counter=0x7fca5316731c, flags=0, prelocking_strategy=0x7fca53167320) at /data/src/10.0/sql/sql_base.cc:4613

#10 0x0000000000707443 in mysql_alter_table (thd=0x7fca4576f070, new_db=0x7fca3d422780 "test", new_name=0x0, create_info=0x7fca531674e0, table_list=0x7fca3d4221a0, alter_info=0x7fca53167450, order_num=0, order=0x0, ignore=false) at /data/src/10.0/sql/sql_table.cc:9120

#11 0x000000000076fd75 in Sql_cmd_alter_table::execute (this=0x7fca3d422980, thd=0x7fca4576f070) at /data/src/10.0/sql/sql_alter.cc:312

#12 0x0000000000654b16 in mysql_execute_command (thd=0x7fca4576f070) at /data/src/10.0/sql/sql_parse.cc:5118

#13 0x000000000065816c in mysql_parse (thd=0x7fca4576f070, rawbuf=0x7fca3d422088 "ALTER TABLE t1 ADD FOREIGN KEY (c) REFERENCES t2 (pk)", length=53, parser_state=0x7fca53168640) at /data/src/10.0/sql/sql_parse.cc:6637

#14 0x000000000064aa8c in dispatch_command (command=COM_QUERY, thd=0x7fca4576f070, packet=0x7fca45775071 "ALTER TABLE t1 ADD FOREIGN KEY (c) REFERENCES t2 (pk)", packet_length=53) at /data/src/10.0/sql/sql_parse.cc:1300

#15 0x0000000000649d8c in do_command (thd=0x7fca4576f070) at /data/src/10.0/sql/sql_parse.cc:1003

#16 0x000000000076b4c8 in do_handle_one_connection (thd_arg=0x7fca4576f070) at /data/src/10.0/sql/sql_connect.cc:1377

#17 0x000000000076b23a in handle_one_connection (arg=0x7fca4576f070) at /data/src/10.0/sql/sql_connect.cc:1292

#18 0x0000000000accfe2 in pfs_spawn_thread (arg=0x7fca45719b70) at /data/src/10.0/storage/perfschema/pfs.cc:1861

#19 0x00007fca52dee494 in start_thread (arg=0x7fca53169700) at pthread_create.c:333

#20 0x00007fca513c293f in clone () from /lib/x86_64-linux-gnu/libc.so.6