diff --git a/src/llv8-constants.cc b/src/llv8-constants.cc
index d56cfcf6..61cd36e0 100644
--- a/src/llv8-constants.cc
+++ b/src/llv8-constants.cc
@@ -496,6 +496,7 @@ void Types::Load() {
   kLastContextType = LoadConstant("LastContextType");
 
   kJSErrorType = LoadConstant("type_JSError__JS_ERROR_TYPE");
+  kJSPromiseType = LoadConstant("type_JSPromise__JS_PROMISE_TYPE");
   kHeapNumberType = LoadConstant("type_HeapNumber__HEAP_NUMBER_TYPE");
   kMapType = LoadConstant("type_Map__MAP_TYPE");
   kGlobalObjectType =
diff --git a/src/llv8-constants.h b/src/llv8-constants.h
index 41ea8f6a..8f1edb27 100644
--- a/src/llv8-constants.h
+++ b/src/llv8-constants.h
@@ -491,6 +491,7 @@ class Types : public Module {
   int64_t kLastContextType;
 
   int64_t kJSErrorType;
+  int64_t kJSPromiseType;
   int64_t kHeapNumberType;
   int64_t kMapType;
   int64_t kGlobalObjectType;
diff --git a/src/llv8-inl.h b/src/llv8-inl.h
index 994bc12d..ddcbdab3 100644
--- a/src/llv8-inl.h
+++ b/src/llv8-inl.h
@@ -239,6 +239,7 @@ inline bool JSObject::IsObjectType(LLV8* v8, int64_t type) {
   return type == v8->types()->kJSObjectType ||
          type == v8->types()->kJSAPIObjectType ||
          type == v8->types()->kJSErrorType ||
+         type == v8->types()->kJSPromiseType ||
          type == v8->types()->kJSSpecialAPIObjectType;
 }