lp:1312618: follow up patch to fix a segfault

[Nirbhay Choubey]

http://bazaar.launchpad.net/~codership/codership-mysql/wsrep-5.5/revision/3994

Suggested fix:

=== modified file 'sql/event_data_objects.cc'
--- sql/event_data_objects.cc 2014-06-19 22:48:20 +0000
+++ sql/event_data_objects.cc 2014-06-25 15:22:01 +0000
@@ -1473,20 +1473,23 @@
       thd->tx_read_only= false;

 #ifdef WITH_WSREP
- // sql_print_information("sizeof(LEX) = %d", sizeof(struct LEX));
- // sizeof(LEX) = 4512, so it's relatively safe to allocate it on stack.
- LEX lex;
- lex.sql_command = SQLCOM_DROP_EVENT;
- thd->lex = &lex;
- WSREP_TO_ISOLATION_BEGIN(WSREP_MYSQL_DB, NULL, NULL);
+ if (WSREP(thd)) {
+ // sql_print_information("sizeof(LEX) = %d", sizeof(struct LEX));
+ // sizeof(LEX) = 4512, so it's relatively safe to allocate it on stack.
+ LEX *old_lex= thd->lex, new_lex;
+ new_lex.sql_command= SQLCOM_DROP_EVENT;
+ thd->lex= &new_lex;
+ WSREP_TO_ISOLATION_BEGIN(WSREP_MYSQL_DB, NULL, NULL);
+ thd->lex= old_lex;
+ }
 #endif
-
+
       ret= Events::drop_event(thd, dbname, name, FALSE);

-#ifdef WITH_WSREP
+#ifdef WITH_WSREP
       WSREP_TO_ISOLATION_END;
   error:
-#endif
+#endif
       thd->tx_read_only= save_tx_read_only;
       thd->security_ctx->master_access= saved_master_access;
     }

[Yan Zhang (yan.zhang)]

fixed in
http://bazaar.launchpad.net/~codership/codership-mysql/wsrep-5.5/revision/4003
http://bazaar.launchpad.net/~codership/codership-mysql/5.6/revision/4102

[Shahriyar Rzayev (rzayev-sehriyar)]

Percona now uses JIRA for bug reports so this bug report is migrated to: https://jira.percona.com/browse/PXC-1010