1 files changed, 13 insertions, 1 deletions
diff --git a/compiler/rustc_data_structures/src/stable_hasher.rs b/compiler/rustc_data_structures/src/stable_hasher.rs
index 0c1fb7518fa..6d75b0fb8a0 100644
--- a/compiler/rustc_data_structures/src/stable_hasher.rs
+++ b/compiler/rustc_data_structures/src/stable_hasher.rs
@@ -1,6 +1,6 @@
 use crate::sip128::SipHasher128;
 use rustc_index::bit_set::{self, BitSet};
-use rustc_index::{Idx, IndexVec};
+use rustc_index::{Idx, IndexSlice, IndexVec};
 use smallvec::SmallVec;
 use std::fmt;
 use std::hash::{BuildHasher, Hash, Hasher};
@@ -597,6 +597,18 @@ where
     }
 }
 
+impl<I: Idx, T, CTX> HashStable<CTX> for IndexSlice<I, T>
+where
+    T: HashStable<CTX>,
+{
+    fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher) {
+        self.len().hash_stable(ctx, hasher);
+        for v in &self.raw {
+            v.hash_stable(ctx, hasher);
+        }
+    }
+}
+
 impl<I: Idx, T, CTX> HashStable<CTX> for IndexVec<I, T>
 where
     T: HashStable<CTX>,