diff --git a/src/conversions.rs b/src/conversions.rs
index c04a37c07..193b0be9b 100644
--- a/src/conversions.rs
+++ b/src/conversions.rs
@@ -27,6 +27,7 @@
 
 #![deny(missing_docs)]
 
+use core::nonzero::NonZero;
 use error::throw_type_error;
 use glue::RUST_JS_NumberValue;
 use jsapi::JSPROP_ENUMERATE;
@@ -619,3 +620,12 @@ impl ToJSValConvertible for *mut JSObject {
         assert!(JS_WrapValue(cx, rval));
     }
 }
+
+// https://heycam.github.io/webidl/#es-object
+impl ToJSValConvertible for NonZero<*mut JSObject> {
+    #[inline]
+    unsafe fn to_jsval(&self, cx: *mut JSContext, rval: MutableHandleValue) {
+        rval.set(ObjectValue(&***self));
+        assert!(JS_WrapValue(cx, rval));
+    }
+}
diff --git a/src/lib.rs b/src/lib.rs
index 5bc9edb3a..24f6c798b 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,13 +5,13 @@
 #![crate_name = "js"]
 #![crate_type = "rlib"]
 
-#![feature(filling_drop)]
 #![feature(link_args)]
+#![feature(nonzero)]
 #![feature(const_fn)]
 
-#![allow(drop_with_repr_extern)]
 #![allow(non_upper_case_globals, non_camel_case_types, non_snake_case, improper_ctypes)]
 
+extern crate core;
 #[macro_use]
 extern crate heapsize;
 #[macro_use]