Avoid palloc(0) when MaxBackends = 1.

diff --git a/src/backend/storage/lmgr/deadlock.c b/src/backend/storage/lmgr/deadlock.c
index 155b1a4..ca892b2 100644 (file)
--- a/src/backend/storage/lmgr/deadlock.c
+++ b/src/backend/storage/lmgr/deadlock.c
@@ -12,7 +12,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/storage/lmgr/deadlock.c,v 1.13 2002/09/04 20:31:25 momjian Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/storage/lmgr/deadlock.c,v 1.14 2002/10/03 19:17:55 tgl Exp $
  *
  *     Interface:
  *
@@ -125,9 +125,11 @@ InitDeadLockChecking(void)
         * We need to consider rearranging at most MaxBackends/2 wait queues
         * (since it takes at least two waiters in a queue to create a soft
         * edge), and the expanded form of the wait queues can't involve more
-        * than MaxBackends total waiters.
+        * than MaxBackends total waiters.  (But avoid palloc(0) if
+        * MaxBackends = 1.)
         */
-       waitOrders = (WAIT_ORDER *) palloc((MaxBackends / 2) * sizeof(WAIT_ORDER));
+       waitOrders = (WAIT_ORDER *)
+               palloc(((MaxBackends + 1) / 2) * sizeof(WAIT_ORDER));
        waitOrderProcs = (PGPROC **) palloc(MaxBackends * sizeof(PGPROC *));
 
        /*