diff --git a/src/elements.cc b/src/elements.cc
index 499af83078..373af84433 100644
--- a/src/elements.cc
+++ b/src/elements.cc
@@ -3339,7 +3339,8 @@ class TypedElementsAccessor
     // them.
     if (source_proto->IsNull(isolate)) return false;
     if (source_proto->IsJSProxy()) return true;
-    if (!context->is_initial_array_prototype(JSObject::cast(source_proto))) {
+    if (!context->native_context()->is_initial_array_prototype(
+            JSObject::cast(source_proto))) {
       return true;
     }
 
diff --git a/test/mjsunit/regress/regress-804288.js b/test/mjsunit/regress/regress-804288.js
new file mode 100644
index 0000000000..6f7855d68c
--- /dev/null
+++ b/test/mjsunit/regress/regress-804288.js
@@ -0,0 +1,9 @@
+// Copyright 2018 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+var arr = [{}];
+Object.setPrototypeOf(arr, {});
+var ta = new Uint8Array(arr);
+
+let kDeclNoLocals = 0;