diff --git a/build.rs b/build.rs
index 9d05678f718c..f4426e190f22 100644
--- a/build.rs
+++ b/build.rs
@@ -13,6 +13,9 @@
 //! This build script was originally taken from the Rocket web framework:
 //! https://github.com/SergioBenitez/Rocket
 
+extern crate ansi_term;
+extern crate rustc_version;
+
 use ansi_term::Colour::Red;
 use rustc_version::{version_meta, version_meta_for, Channel, Version, VersionMeta};
 use std::env;