*** pgsql/src/backend/executor/execMain.c	2009/12/09 21:57:51	1.336
--- pgsql/src/backend/executor/execMain.c	2009/12/11 18:14:43	1.337
***************
*** 26,32 ****
   *
   *
   * IDENTIFICATION
!  *	  $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.335 2009/11/20 20:38:10 tgl Exp $
   *
   *-------------------------------------------------------------------------
   */
--- 26,32 ----
   *
   *
   * IDENTIFICATION
!  *	  $PostgreSQL: pgsql/src/backend/executor/execMain.c,v 1.336 2009/12/09 21:57:51 tgl Exp $
   *
   *-------------------------------------------------------------------------
   */
*************** EvalPlanQual(EState *estate, EPQState *e
*** 1408,1413 ****
--- 1408,1423 ----
  	slot = EvalPlanQualNext(epqstate);
  
  	/*
+ 	 * If we got a tuple, force the slot to materialize the tuple so that
+ 	 * it is not dependent on any local state in the EPQ query (in particular,
+ 	 * it's highly likely that the slot contains references to any pass-by-ref
+ 	 * datums that may be present in copyTuple).  As with the next step,
+ 	 * this is to guard against early re-use of the EPQ query.
+ 	 */
+ 	if (!TupIsNull(slot))
+ 		(void) ExecMaterializeSlot(slot);
+ 
+ 	/*
  	 * Clear out the test tuple.  This is needed in case the EPQ query
  	 * is re-used to test a tuple for a different relation.  (Not clear
  	 * that can really happen, but let's be safe.)