diff --git a/src/backend/executor/nodeLimit.c b/src/backend/executor/nodeLimit.c
index 12cfc5177b..99d33fbc21 100644
--- a/src/backend/executor/nodeLimit.c
+++ b/src/backend/executor/nodeLimit.c
@@ -212,6 +212,8 @@ ExecLimit(PlanState *pstate)
 				node->position--;
 				break;
 			}
+			Assert(node->lstate == LIMIT_WINDOWEND_TIES);
+			/* fall-through */
 
 		case LIMIT_WINDOWEND_TIES:
 			if (ScanDirectionIsForward(direction))