diff --git a/packages/compiler-sfc/src/script/resolveType.ts b/packages/compiler-sfc/src/script/resolveType.ts
index 1324b916911..171e6a7a3d3 100644
--- a/packages/compiler-sfc/src/script/resolveType.ts
+++ b/packages/compiler-sfc/src/script/resolveType.ts
@@ -341,7 +341,7 @@ function resolveInterfaceMembers(
           }
         }
         if (calls) {
-          ;(base.calls || (base.calls = [])).push(...calls)
+          ;(base.calls ||= [])).push(...calls)
         }
       } catch (e) {
         ctx.error(