diff --git a/src/wasm/wasm-js.cc b/src/wasm/wasm-js.cc
index 83009d7..8a4b2ff 100644
--- a/src/wasm/wasm-js.cc
+++ b/src/wasm/wasm-js.cc
@@ -34,7 +34,6 @@
   size_t size() { return static_cast<size_t>(end - start); }
 };
 
-
 RawBuffer GetRawBufferArgument(
     ErrorThrower& thrower, const v8::FunctionCallbackInfo<v8::Value>& args) {
   if (args.Length() < 1) {
@@ -77,7 +76,6 @@
   return {start, end};
 }
 
-
 void VerifyModule(const v8::FunctionCallbackInfo<v8::Value>& args) {
   HandleScope scope(args.GetIsolate());
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(args.GetIsolate());
@@ -98,7 +96,6 @@
   if (result.val) delete result.val;
 }
 
-
 void VerifyFunction(const v8::FunctionCallbackInfo<v8::Value>& args) {
   HandleScope scope(args.GetIsolate());
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(args.GetIsolate());
@@ -134,6 +131,11 @@
     return nullptr;
   }
 
+  if (info->scope()->declarations()->length() == 0) {
+    thrower->Error("Asm.js validation failed: no declarations in scope");
+    return nullptr;
+  }
+
   info->set_literal(
       info->scope()->declarations()->at(0)->AsFunctionDeclaration()->fun());
 
@@ -180,10 +182,10 @@
     thrower->Failed("", result);
   } else {
     // Success. Instantiate the module and return the object.
-    i::Handle<i::JSObject> ffi = i::Handle<i::JSObject>::null();
+    i::Handle<i::JSReceiver> ffi = i::Handle<i::JSObject>::null();
     if (args.Length() > 1 && args[1]->IsObject()) {
       Local<Object> obj = Local<Object>::Cast(args[1]);
-      ffi = i::Handle<i::JSObject>::cast(v8::Utils::OpenHandle(*obj));
+      ffi = i::Handle<i::JSReceiver>::cast(v8::Utils::OpenHandle(*obj));
     }
 
     i::MaybeHandle<i::JSObject> object =
@@ -197,7 +199,6 @@
   if (result.val) delete result.val;
 }
 
-
 void InstantiateModuleFromAsm(const v8::FunctionCallbackInfo<v8::Value>& args) {
   HandleScope scope(args.GetIsolate());
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(args.GetIsolate());
@@ -229,7 +230,6 @@
                           internal::wasm::kAsmJsOrigin);
 }
 
-
 void InstantiateModule(const v8::FunctionCallbackInfo<v8::Value>& args) {
   HandleScope scope(args.GetIsolate());
   i::Isolate* isolate = reinterpret_cast<i::Isolate*>(args.GetIsolate());
@@ -243,7 +243,6 @@
 }
 }  // namespace
 
-
 // TODO(titzer): we use the API to create the function template because the
 // internal guts are too ugly to replicate here.
 static i::Handle<i::FunctionTemplateInfo> NewTemplate(i::Isolate* i_isolate,
@@ -253,13 +252,11 @@
   return v8::Utils::OpenHandle(*local);
 }
 
-
 namespace internal {
 static Handle<String> v8_str(Isolate* isolate, const char* str) {
   return isolate->factory()->NewStringFromAsciiChecked(str);
 }
 
-
 static void InstallFunc(Isolate* isolate, Handle<JSObject> object,
                         const char* str, FunctionCallback func) {
   Handle<String> name = v8_str(isolate, str);
@@ -271,7 +268,6 @@
   JSObject::AddProperty(object, name, function, attributes);
 }
 
-
 void WasmJs::Install(Isolate* isolate, Handle<JSGlobalObject> global) {
   // Setup wasm function map.
   Handle<Context> context(global->native_context(), isolate);
@@ -294,8 +290,16 @@
   InstallFunc(isolate, wasm_object, "instantiateModule", InstantiateModule);
   InstallFunc(isolate, wasm_object, "instantiateModuleFromAsm",
               InstantiateModuleFromAsm);
-}
 
+  {
+    // Add the Wasm.experimentalVersion property.
+    Handle<String> name = v8_str(isolate, "experimentalVersion");
+    PropertyAttributes attributes =
+        static_cast<PropertyAttributes>(DONT_DELETE | READ_ONLY);
+    Handle<Smi> value = Handle<Smi>(Smi::FromInt(wasm::kWasmVersion), isolate);
+    JSObject::AddProperty(wasm_object, name, value, attributes);
+  }
+}
 
 void WasmJs::InstallWasmFunctionMap(Isolate* isolate, Handle<Context> context) {
   if (!context->get(Context::WASM_FUNCTION_MAP_INDEX)->IsMap()) {