diff --git a/src/lib.rs b/src/lib.rs
index 29ddc0a..ea01ed6 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -283,7 +283,7 @@ impl Constraint {
 }
 
 /// Policy for resource allocation.
-#[derive(Copy, Clone, Debug, PartialEq)]
+#[derive(Copy, Clone, Debug, PartialEq, Eq)]
 pub enum AllocPolicy {
     /// Allocate the first matched entry.
     FirstMatch,