mysqld: /data/src/10.2/sql/sql_base.cc:730: void close_thread_tables(THD*): Assertion `thd->transaction.stmt.is_empty() || thd->in_sub_stmt || (thd->state_flags & Open_tables_state::BACKUPS_AVAIL)' failed.

170407  2:13:06 [ERROR] mysqld got signal 6 ;

#7  0x00007f3b838a4312 in __GI___assert_fail (assertion=0x7f3b8699dc18 "thd->transaction.stmt.is_empty() || thd->in_sub_stmt || (thd->state_flags & Open_tables_state::BACKUPS_AVAIL)", file=0x7f3b8699d9f0 "/data/src/10.2/sql/sql_base.cc", line=730, function=0x7f3b8699f5b0 <close_thread_tables(THD*)::__PRETTY_FUNCTION__> "void close_thread_tables(THD*)") at assert.c:101

#8  0x00007f3b85ed7bc8 in close_thread_tables (thd=0x7f3b18000b00) at /data/src/10.2/sql/sql_base.cc:729

#9  0x00007f3b860c5aab in flush_tables_with_read_lock (thd=0x7f3b18000b00, all_tables=0x7f3b18010f58) at /data/src/10.2/sql/sql_reload.cc:588

#10 0x00007f3b85f51188 in mysql_execute_command (thd=0x7f3b18000b00) at /data/src/10.2/sql/sql_parse.cc:5320

#11 0x00007f3b85f589da in mysql_parse (thd=0x7f3b18000b00, rawbuf=0x7f3b18010e78 "FLUSH TABLE t1 FOR EXPORT", length=25, parser_state=0x7f3b85811260, is_com_multi=false, is_next_command=false) at /data/src/10.2/sql/sql_parse.cc:7874

#12 0x00007f3b85f46ab2 in dispatch_command (command=COM_QUERY, thd=0x7f3b18000b00, packet=0x7f3b18017fa1 "FLUSH TABLE t1 FOR EXPORT", packet_length=25, is_com_multi=false, is_next_command=false) at /data/src/10.2/sql/sql_parse.cc:1812

#13 0x00007f3b85f45422 in do_command (thd=0x7f3b18000b00) at /data/src/10.2/sql/sql_parse.cc:1362

#14 0x00007f3b8608f9e9 in do_handle_one_connection (connect=0x7f3b89175470) at /data/src/10.2/sql/sql_connect.cc:1354

#15 0x00007f3b8608f776 in handle_one_connection (arg=0x7f3b89175470) at /data/src/10.2/sql/sql_connect.cc:1260

#16 0x00007f3b8556e064 in start_thread (arg=0x7f3b85812700) at pthread_create.c:309

#17 0x00007f3b8395e62d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:111

INSTALL SONAME 'ha_rocksdb';

CREATE TABLE t1 (i INT) ENGINE=RocksDB;

FLUSH TABLE t1 FOR EXPORT;