diff --git a/src/backend/optimizer/plan/initsplan.c b/src/backend/optimizer/plan/initsplan.c
index 8e913c92d8..8dc39765f2 100644
--- a/src/backend/optimizer/plan/initsplan.c
+++ b/src/backend/optimizer/plan/initsplan.c
@@ -355,7 +355,8 @@ create_aggregate_grouped_var_infos(PlannerInfo *root)
 	Assert(root->grouped_var_list == NIL);
 
 	tlist_exprs = pull_var_clause((Node *) root->processed_tlist,
-								  PVC_INCLUDE_AGGREGATES);
+								  PVC_INCLUDE_AGGREGATES |
+								  PVC_RECURSE_WINDOWFUNCS);
 
 	/*
 	 * Although GroupingFunc is related to root->parse->groupingSets, this