BUG#57288: binlog_tmp_table fails sporadically: "Failed to write
the DROP statement ..." Problem: When using temporary tables and closing a session, an implicit DROP TEMPORARY TABLE IF EXISTS is written to the binary log (while cleaning up the context of the session THD - see: sql_class.cc:THD::cleanup which calls close_temporary_tables). close_temporary_tables, first checks if the binary log is opened and then proceeds to creating the DROP statements. Then, such statements, are written to the binary log through MYSQL_BIN_LOG::write(Log_event *). Inside, there is another check if the binary log is opened and if not an error is returned. This is where the faulty behavior is triggered. Given that the test case replays a binary log, with temp tables statements, and right after it issues RESET MASTER, there is a chance that is_open will report false (when the mysql session is closed and the temporary tables are written). is_open may return false, because MYSQL_BIN_LOG::reset_logs is not setting the correct flag (LOG_CLOSE_TO_BE_OPENED), on the MYSQL_LOG_BIN::log_state (instead it sets just the LOG_CLOSE_INDEX flag, leaving the log_state to LOG_CLOSED). Thence, when writing the DROP statement as part of the THD::cleanup, the thread could get a return value of false for is_open - inside MYSQL_BIN_LOG::write, ultimately reporting that it can't write the event to the binary log. Fix: We fix this by adding the correct flag, missing in the second close.
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