Only store a LocalDefId in hir::MacroDef.

compiler/rustc_hir/src/hir.rs

@@ -761,16 +761,22 @@ impl Crate<'_> {
 /// A macro definition, in this crate or imported from another.
 ///
 /// Not parsed directly, but created on macro import or `macro_rules!` expansion.
-#[derive(Debug, HashStable_Generic)]
+#[derive(Debug)]
 pub struct MacroDef<'hir> {
     pub ident: Ident,
     pub vis: Visibility<'hir>,
     pub attrs: &'hir [Attribute],
-    pub hir_id: HirId,
+    pub def_id: LocalDefId,
     pub span: Span,
     pub ast: ast::MacroDef,
 }
 
+impl MacroDef<'_> {
+    pub fn hir_id(&self) -> HirId {
+        HirId::make_owner(self.def_id)
+    }
+}
+
 /// A block of statements `{ .. }`, which may have a label (in this case the
 /// `targeted_by_break` field will be `true`) and may be `unsafe` by means of
 /// the `rules` being anything but `DefaultBlock`.
@@ -2941,7 +2947,8 @@ impl<'hir> Node<'hir> {
             Node::Item(Item { def_id, .. })
             | Node::TraitItem(TraitItem { def_id, .. })
             | Node::ImplItem(ImplItem { def_id, .. })
-            | Node::ForeignItem(ForeignItem { def_id, .. }) => Some(HirId::make_owner(*def_id)),
+            | Node::ForeignItem(ForeignItem { def_id, .. })
+            | Node::MacroDef(MacroDef { def_id, .. }) => Some(HirId::make_owner(*def_id)),
             Node::Field(StructField { hir_id, .. })
             | Node::AnonConst(AnonConst { hir_id, .. })
             | Node::Expr(Expr { hir_id, .. })
@@ -2952,7 +2959,6 @@ impl<'hir> Node<'hir> {
             | Node::Arm(Arm { hir_id, .. })
             | Node::Block(Block { hir_id, .. })
             | Node::Local(Local { hir_id, .. })
-            | Node::MacroDef(MacroDef { hir_id, .. })
             | Node::Lifetime(Lifetime { hir_id, .. })
             | Node::Param(Param { hir_id, .. })
             | Node::GenericParam(GenericParam { hir_id, .. }) => Some(*hir_id),

compiler/rustc_hir/src/intravisit.rs

@@ -489,7 +489,7 @@ pub fn walk_crate<'v, V: Visitor<'v>>(visitor: &mut V, krate: &'v Crate<'v>) {
 }
 
 pub fn walk_macro_def<'v, V: Visitor<'v>>(visitor: &mut V, macro_def: &'v MacroDef<'v>) {
-    visitor.visit_id(macro_def.hir_id);
+    visitor.visit_id(macro_def.hir_id());
     visitor.visit_ident(macro_def.ident);
     walk_list!(visitor, visit_attribute, macro_def.attrs);
 }

compiler/rustc_hir/src/stable_hash_impls.rs

@@ -1,8 +1,8 @@
 use rustc_data_structures::stable_hasher::{HashStable, StableHasher, ToStableHashKey};
 
 use crate::hir::{
-    BodyId, Expr, ForeignItem, ForeignItemId, ImplItem, ImplItemId, Item, ItemId, Mod, TraitItem,
-    TraitItemId, Ty, VisibilityKind,
+    BodyId, Expr, ForeignItem, ForeignItemId, ImplItem, ImplItemId, Item, ItemId, MacroDef, Mod,
+    TraitItem, TraitItemId, Ty, VisibilityKind,
 };
 use crate::hir_id::{HirId, ItemLocalId};
 use rustc_span::def_id::{DefPathHash, LocalDefId};
@@ -203,3 +203,17 @@ impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for Item<'_> {
         });
     }
 }
+
+impl<HirCtx: crate::HashStableContext> HashStable<HirCtx> for MacroDef<'_> {
+    fn hash_stable(&self, hcx: &mut HirCtx, hasher: &mut StableHasher) {
+        let MacroDef { ident, ref attrs, def_id: _, ref ast, ref vis, span } = *self;
+
+        hcx.hash_hir_item_like(|hcx| {
+            ident.name.hash_stable(hcx, hasher);
+            attrs.hash_stable(hcx, hasher);
+            ast.hash_stable(hcx, hasher);
+            vis.hash_stable(hcx, hasher);
+            span.hash_stable(hcx, hasher);
+        });
+    }
+}