Panic when hashing node IDs

Author: Zoxc

src/librustc/ich/hcx.rs

@@ -219,12 +219,9 @@ impl<'a> ToStableHashKey<StableHashingContext<'a>> for hir::HirId {
     }
 }
 
-impl<'a> ToStableHashKey<StableHashingContext<'a>> for ast::NodeId {
-    type KeyType = Self;
-
-    #[inline]
-    fn to_stable_hash_key(&self, _: &StableHashingContext<'a>) -> Self {
-        *self
+impl<'a> HashStable<StableHashingContext<'a>> for ast::NodeId {
+    fn hash_stable(&self, _: &mut StableHashingContext<'a>, _: &mut StableHasher) {
+        panic!("Node IDs should not appear in incremental state");
     }
 }
 

src/libsyntax/node_id.rs

@@ -1,10 +1,8 @@
-use rustc_macros::HashStable_Generic;
 use rustc_serialize::{Decoder, Encoder};
 use rustc_span::ExpnId;
 use std::fmt;
 
 rustc_index::newtype_index! {
-    #[derive(HashStable_Generic)]
     pub struct NodeId {
         ENCODABLE = custom
         DEBUG_FORMAT = "NodeId({})"