--- a/toolkit/library/rust/shared/lib.rs
+++ b/toolkit/library/rust/shared/lib.rs
@@ -1,15 +1,15 @@
 // This Source Code Form is subject to the terms of the Mozilla Public
 // License, v. 2.0. If a copy of the MPL was not distributed with this
 // file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 #![cfg_attr(feature = "oom_with_global_alloc",
             feature(global_allocator, alloc, alloc_system, allocator_api))]
-#![cfg_attr(feature = "oom_with_hook", feature(oom_hook))]
+#![cfg_attr(feature = "oom_with_hook", feature(oom_hook, allocator_api))]
 
 #[cfg(feature="servo")]
 extern crate geckoservo;
 
 extern crate mp4parse_capi;
 extern crate nsstring;
 extern crate nserror;
 extern crate xpcom;