Fix bug in 64-bit xids.

Alexander Korotkov · Alexander Korotkov · commit 4614669f7f64 · 2017-05-10T17:10:27.000+03:00
Set xmax to heap tuple after setting infromask.
Previously, multixid could be messed up with normal xid.
diff --git a/src/backend/access/heap/heapam.c b/src/backend/access/heap/heapam.c
@@ -4442,9 +4442,9 @@ heap_update(Relation relation, ItemPointer otid, HeapTuple newtup,
 		HeapTupleClearHotUpdated(&oldtup);
 		/* ... and store info about transaction updating this tuple */
 		Assert(TransactionIdIsValid(xmax_lock_old_tuple));
-		HeapTupleSetXmax(&oldtup, xmax_lock_old_tuple);
 		oldtup.t_data->t_infomask |= infomask_lock_old_tuple;
 		oldtup.t_data->t_infomask2 |= infomask2_lock_old_tuple;
+		HeapTupleSetXmax(&oldtup, xmax_lock_old_tuple);
 		HeapTupleHeaderSetCmax(oldtup.t_data, cid, iscombo);
 
 		/* temporarily make it look not-updated, but locked */
