diff --git a/compiler/rustc_data_structures/src/stable_hasher.rs b/compiler/rustc_data_structures/src/stable_hasher.rs
index b8ad66901c6..5e07697f0dd 100644
--- a/compiler/rustc_data_structures/src/stable_hasher.rs
+++ b/compiler/rustc_data_structures/src/stable_hasher.rs
@@ -377,9 +377,8 @@ fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher) {
 
 impl<CTX> HashStable<CTX> for str {
     #[inline]
-    fn hash_stable(&self, _: &mut CTX, hasher: &mut StableHasher) {
-        self.len().hash(hasher);
-        self.as_bytes().hash(hasher);
+    fn hash_stable(&self, ctx: &mut CTX, hasher: &mut StableHasher) {
+        self.as_bytes().hash_stable(ctx, hasher);
     }
 }