diff --git a/src/lib.rs b/src/lib.rs
index ca7e4a6..9e1a575 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -15,6 +15,8 @@
 #![feature(macro_rules, asm, globs)]
 #![no_std]
 
+extern crate core;
+
 #[cfg(test)]
 extern crate std;