ha_innodb.cc, handler.cc:

  Fix the BDB crash in the previous push; to save CPU remove duplicate calls of commit in InnoDB

sql/handler.cc

@@ -209,44 +209,26 @@ void ha_close_connection(THD* thd)
 
 /*
   This is used to commit or rollback a single statement depending on the value
-  of error. If the autocommit is on, then we will commit or rollback the whole
-  transaction (= the statement). The autocommit mechanism built into handlers
-  is based on counting locks, but if the user has used LOCK TABLES then that
-  mechanism does not know to do the commit.
+  of error. Note that if the autocommit is on, then the following call inside
+  InnoDB will commit or rollback the whole transaction (= the statement). The
+  autocommit mechanism built into InnoDB is based on counting locks, but if
+  the user has used LOCK TABLES then that mechanism does not know to do the
+  commit.
 */
 
 int ha_autocommit_or_rollback(THD *thd, int error)
 {
-  bool do_autocommit=FALSE;
-
   DBUG_ENTER("ha_autocommit_or_rollback");
 #ifdef USING_TRANSACTIONS
-
-  if (!(thd->options & (OPTION_NOT_AUTOCOMMIT | OPTION_BEGIN)))
-    do_autocommit=TRUE;  /* We can commit or rollback the whole transaction */
-
   if (opt_using_transactions)
   {
     if (!error)
-    {
-      if (do_autocommit)
-      {
-	if (ha_commit(thd))
-	  error=1;
-      }
-      else
     {
       if (ha_commit_stmt(thd))
 	error=1;
     }
-    }
-    else
-    {
-      if (do_autocommit)
-	(void) ha_rollback(thd);
     else
       (void) ha_rollback_stmt(thd);
-    }
 
     thd->variables.tx_isolation=thd->session_tx_isolation;
   }