diff --git a/src/backend/utils/mmgr/portalmem.c b/src/backend/utils/mmgr/portalmem.c
index 7409593c968..47437db1224 100644
--- a/src/backend/utils/mmgr/portalmem.c
+++ b/src/backend/utils/mmgr/portalmem.c
@@ -1151,6 +1151,9 @@ pg_cursor(PG_FUNCTION_ARGS)
 		/* report only "visible" entries */
 		if (!portal->visible)
 			continue;
+		/* also ignore it if PortalDefineQuery hasn't been called yet */
+		if (!portal->sourceText)
+			continue;
 
 		MemSet(nulls, 0, sizeof(nulls));