diff --git a/packages/compiler-sfc/src/parse.ts b/packages/compiler-sfc/src/parse.ts
index 98b08a208..01d0794e0 100644
--- a/packages/compiler-sfc/src/parse.ts
+++ b/packages/compiler-sfc/src/parse.ts
@@ -84,7 +84,7 @@ export interface SFCDescriptor {
    */
   slotted: boolean
 
-  vapor: boolean
+  vapor?: boolean
 
   /**
    * compare with an existing descriptor to determine whether HMR should perform