1 files changed, 12 insertions, 0 deletions
diff --git a/compiler/rustc_serialize/src/serialize.rs b/compiler/rustc_serialize/src/serialize.rs
index ecc8dae0480..e32e4493726 100644
--- a/compiler/rustc_serialize/src/serialize.rs
+++ b/compiler/rustc_serialize/src/serialize.rs
@@ -366,6 +366,18 @@ direct_serialize_impls! {
     char emit_char read_char
 }
 
+impl<S: Encoder> Encodable<S> for ! {
+    fn encode(&self, _s: &mut S) -> Result<(), S::Error> {
+        unreachable!()
+    }
+}
+
+impl<D: Decoder> Decodable<D> for ! {
+    fn decode(_d: &mut D) -> Result<!, D::Error> {
+        unreachable!()
+    }
+}
+
 impl<S: Encoder> Encodable<S> for ::std::num::NonZeroU32 {
     fn encode(&self, s: &mut S) -> Result<(), S::Error> {
         s.emit_u32(self.get())