Use derive macro for HashStable

1 files changed, 10 insertions, 0 deletions

diff --git a/src/librustc_data_structures/thin_vec.rs b/src/librustc_data_structures/thin_vec.rs
index ed57c528f51..52f23f4893e 100644
--- a/src/librustc_data_structures/thin_vec.rs
+++ b/src/librustc_data_structures/thin_vec.rs
@@ -1,3 +1,5 @@
+use crate::stable_hasher::{StableHasher, StableHasherResult, HashStable};
+
 /// A vector type optimized for cases where this size is usually 0 (cf. `SmallVector`).
 /// The `Option<Box<..>>` wrapping allows us to represent a zero sized vector with `None`,
 /// which uses only a single (null) pointer.
@@ -56,3 +58,11 @@ impl<T> Extend<T> for ThinVec<T> {
         }
     }
 }
+
+impl<T: HashStable<CTX>, CTX> HashStable<CTX> for ThinVec<T> {
+    fn hash_stable<W: StableHasherResult>(&self,
+                                          hcx: &mut CTX,
+                                          hasher: &mut StableHasher<W>) {
+        (**self).hash_stable(hcx, hasher)
+    }
+}