diff --git a/bigint/src/lib.rs b/bigint/src/lib.rs
index 4f5b0a3..443e8a2 100644
--- a/bigint/src/lib.rs
+++ b/bigint/src/lib.rs
@@ -79,6 +79,7 @@ use std::num::ParseIntError;
 use std::ops::{Add, BitAnd, BitOr, BitXor, Div, Mul, Neg, Rem, Shl, Shr, Sub};
 use std::str::{self, FromStr};
 use std::fmt;
+#[cfg(test)]
 use std::hash;
 use std::cmp::Ordering::{self, Less, Greater, Equal};
 use std::{f32, f64};
diff --git a/rational/src/lib.rs b/rational/src/lib.rs
index 09ecafb..529ff74 100644
--- a/rational/src/lib.rs
+++ b/rational/src/lib.rs
@@ -21,6 +21,7 @@ extern crate num_integer as integer;
 use std::cmp;
 use std::error::Error;
 use std::fmt;
+#[cfg(test)]
 use std::hash;
 use std::ops::{Add, Div, Mul, Neg, Rem, Sub};
 use std::str::FromStr;