Fix oversight in my recent patch to allow ExecMakeFunctionResult to handle

materialize-mode set results.  Since it now uses the ReturnSetInfo node
to hold internal state, we need to be sure to set up the node even when
the immediately called function doesn't return set (but does have a set-valued
argument).  Per report from Anupama Aherrao.

src/backend/executor/execQual.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $PostgreSQL: pgsql/src/backend/executor/execQual.c,v 1.237 2008/11/15 20:52:35 petere Exp $
+ *	  $PostgreSQL: pgsql/src/backend/executor/execQual.c,v 1.238 2008/12/18 19:38:22 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -1433,23 +1433,6 @@ restart:
 		fcache->setArgsValid = false;
 	}
 
-	/*
-	 * If function returns set, prepare a resultinfo node for communication
-	 */
-	if (fcache->func.fn_retset)
-	{
-		fcinfo->resultinfo = (Node *) &rsinfo;
-		rsinfo.type = T_ReturnSetInfo;
-		rsinfo.econtext = econtext;
-		rsinfo.expectedDesc = fcache->funcResultDesc;
-		rsinfo.allowedModes = (int) (SFRM_ValuePerCall | SFRM_Materialize);
-		/* note we do not set SFRM_Materialize_Random or _Preferred */
-		rsinfo.returnMode = SFRM_ValuePerCall;
-		/* isDone is filled below */
-		rsinfo.setResult = NULL;
-		rsinfo.setDesc = NULL;
-	}
-
 	/*
 	 * Now call the function, passing the evaluated parameter values.
 	 */
@@ -1464,6 +1447,23 @@ restart:
 					(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
 					 errmsg("set-valued function called in context that cannot accept a set")));
 
+		/*
+		 * Prepare a resultinfo node for communication.  If the function
+		 * doesn't itself return set, we don't pass the resultinfo to the
+		 * function, but we need to fill it in anyway for internal use.
+		 */
+		if (fcache->func.fn_retset)
+			fcinfo->resultinfo = (Node *) &rsinfo;
+		rsinfo.type = T_ReturnSetInfo;
+		rsinfo.econtext = econtext;
+		rsinfo.expectedDesc = fcache->funcResultDesc;
+		rsinfo.allowedModes = (int) (SFRM_ValuePerCall | SFRM_Materialize);
+		/* note we do not set SFRM_Materialize_Random or _Preferred */
+		rsinfo.returnMode = SFRM_ValuePerCall;
+		/* isDone is filled below */
+		rsinfo.setResult = NULL;
+		rsinfo.setDesc = NULL;
+
 		/*
 		 * This loop handles the situation where we have both a set argument
 		 * and a set-valued function.  Once we have exhausted the function's