diff --git a/src/backend/optimizer/plan/planagg.c b/src/backend/optimizer/plan/planagg.c
index 805aae7ee7a..4216fc4a6ea 100644
--- a/src/backend/optimizer/plan/planagg.c
+++ b/src/backend/optimizer/plan/planagg.c
@@ -103,6 +103,14 @@ preprocess_minmax_aggregates(PlannerInfo *root, List *tlist)
 		parse->hasWindowFuncs)
 		return;
 
+	/*
+	 * Reject if query contains any CTEs; there's no way to build an indexscan
+	 * on one so we couldn't succeed here.  (If the CTEs are unreferenced,
+	 * that's not true, but it doesn't seem worth expending cycles to check.)
+	 */
+	if (parse->cteList)
+		return;
+
 	/*
 	 * We also restrict the query to reference exactly one table, since join
 	 * conditions can't be handled reasonably.  (We could perhaps handle a
@@ -360,7 +368,6 @@ build_minmax_path(PlannerInfo *root, MinMaxAggInfo *mminfo,
 	subroot->plan_params = NIL;
 	subroot->outer_params = NULL;
 	subroot->init_plans = NIL;
-	subroot->cte_plan_ids = NIL;
 
 	subroot->parse = parse = (Query *) copyObject(root->parse);
 	IncrementVarSublevelsUp((Node *) parse, 1, 1);