diff --git a/openssl/src/x509/mod.rs b/openssl/src/x509/mod.rs
index 31a6cae890820ed8e459bb55250e89c75ce345a1..1319b75c7c567b6e05d4b086b5612c7d60119fe7 100644
--- a/openssl/src/x509/mod.rs
+++ b/openssl/src/x509/mod.rs
@@ -10,7 +10,10 @@ use std::collections::HashMap;
 use std::marker::PhantomData;
 
 use HashTypeInternals;
-use asn1::{Asn1Time, Asn1TimeRef};
+use asn1::Asn1Time;
+#[cfg(feature = "x509_expiry")]
+use asn1::Asn1TimeRef;
+
 use bio::{MemBio, MemBioSlice};
 use crypto::hash;
 use crypto::hash::Type as HashType;