1 files changed, 15 insertions, 1 deletions
diff --git a/compiler/rustc_hir/src/def.rs b/compiler/rustc_hir/src/def.rs
index cca5ead0f83..f1801a0f844 100644
--- a/compiler/rustc_hir/src/def.rs
+++ b/compiler/rustc_hir/src/def.rs
@@ -2,6 +2,8 @@ use crate::hir;
 
 use rustc_ast as ast;
 use rustc_ast::NodeId;
+use rustc_data_structures::fx::FxHashMap;
+use rustc_data_structures::stable_hasher::ToStableHashKey;
 use rustc_macros::HashStable_Generic;
 use rustc_span::def_id::{DefId, LocalDefId};
 use rustc_span::hygiene::MacroKind;
@@ -472,7 +474,8 @@ impl PartialRes {
 
 /// Different kinds of symbols can coexist even if they share the same textual name.
 /// Therefore, they each have a separate universe (known as a "namespace").
-#[derive(Copy, Clone, PartialEq, Eq, Hash, Debug)]
+#[derive(Copy, Clone, PartialEq, Eq, PartialOrd, Ord, Hash, Debug, Encodable, Decodable)]
+#[derive(HashStable_Generic)]
 pub enum Namespace {
     /// The type namespace includes `struct`s, `enum`s, `union`s, `trait`s, and `mod`s
     /// (and, by extension, crates).
@@ -499,6 +502,15 @@ impl Namespace {
     }
 }
 
+impl<CTX: crate::HashStableContext> ToStableHashKey<CTX> for Namespace {
+    type KeyType = Namespace;
+
+    #[inline]
+    fn to_stable_hash_key(&self, _: &CTX) -> Namespace {
+        *self
+    }
+}
+
 /// Just a helper ‒ separate structure for each namespace.
 #[derive(Copy, Clone, Default, Debug)]
 pub struct PerNS<T> {
@@ -760,3 +772,5 @@ pub enum LifetimeRes {
     /// HACK: This is used to recover the NodeId of an elided lifetime.
     ElidedAnchor { start: NodeId, end: NodeId },
 }
+
+pub type DocLinkResMap = FxHashMap<(Symbol, Namespace), Option<Res<NodeId>>>;