diff --git a/src/librustc/hir/check_attr.rs b/src/librustc/hir/check_attr.rs
index d5acde2f463..6fbb8d783d4 100644
--- a/src/librustc/hir/check_attr.rs
+++ b/src/librustc/hir/check_attr.rs
@@ -107,7 +107,7 @@ impl Target {
         }
     }
 
-    fn from_trait_item(trait_item: &TraitItem) -> Target {
+    fn from_trait_item(trait_item: &TraitItem<'_>) -> Target {
         match trait_item.kind {
             TraitItemKind::Const(..) => Target::AssocConst,
             TraitItemKind::Method(_, hir::TraitMethod::Required(_)) => {
@@ -498,7 +498,7 @@ impl Visitor<'tcx> for CheckAttrVisitor<'tcx> {
         intravisit::walk_item(self, item)
     }
 
-    fn visit_trait_item(&mut self, trait_item: &'tcx TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &'tcx TraitItem<'tcx>) {
         let target = Target::from_trait_item(trait_item);
         self.check_attributes(trait_item.hir_id, &trait_item.attrs, &trait_item.span, target, None);
         intravisit::walk_trait_item(self, trait_item)
diff --git a/src/librustc/hir/intravisit.rs b/src/librustc/hir/intravisit.rs
index d10b5cd0373..6143e2281e4 100644
--- a/src/librustc/hir/intravisit.rs
+++ b/src/librustc/hir/intravisit.rs
@@ -295,7 +295,7 @@ pub trait Visitor<'v>: Sized {
     fn visit_use(&mut self, path: &'v Path, hir_id: HirId) {
         walk_use(self, path, hir_id)
     }
-    fn visit_trait_item(&mut self, ti: &'v TraitItem) {
+    fn visit_trait_item(&mut self, ti: &'v TraitItem<'v>) {
         walk_trait_item(self, ti)
     }
     fn visit_trait_item_ref(&mut self, ii: &'v TraitItemRef) {
@@ -849,9 +849,9 @@ pub fn walk_fn<'v, V: Visitor<'v>>(visitor: &mut V,
     visitor.visit_nested_body(body_id)
 }
 
-pub fn walk_trait_item<'v, V: Visitor<'v>>(visitor: &mut V, trait_item: &'v TraitItem) {
+pub fn walk_trait_item<'v, V: Visitor<'v>>(visitor: &mut V, trait_item: &'v TraitItem<'v>) {
     visitor.visit_ident(trait_item.ident);
-    walk_list!(visitor, visit_attribute, &trait_item.attrs);
+    walk_list!(visitor, visit_attribute, trait_item.attrs);
     visitor.visit_generics(&trait_item.generics);
     match trait_item.kind {
         TraitItemKind::Const(ref ty, default) => {
diff --git a/src/librustc/hir/itemlikevisit.rs b/src/librustc/hir/itemlikevisit.rs
index 4d3fd5e05b4..723cede0be6 100644
--- a/src/librustc/hir/itemlikevisit.rs
+++ b/src/librustc/hir/itemlikevisit.rs
@@ -46,7 +46,7 @@ use super::intravisit::Visitor;
 /// needed.
 pub trait ItemLikeVisitor<'hir> {
     fn visit_item(&mut self, item: &'hir Item<'hir>);
-    fn visit_trait_item(&mut self, trait_item: &'hir TraitItem);
+    fn visit_trait_item(&mut self, trait_item: &'hir TraitItem<'hir>);
     fn visit_impl_item(&mut self, impl_item: &'hir ImplItem);
 }
 
@@ -69,7 +69,7 @@ impl<'v, 'hir, V> ItemLikeVisitor<'hir> for DeepVisitor<'v, V>
         self.visitor.visit_item(item);
     }
 
-    fn visit_trait_item(&mut self, trait_item: &'hir TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &'hir TraitItem<'hir>) {
         self.visitor.visit_trait_item(trait_item);
     }
 
@@ -81,7 +81,7 @@ impl<'v, 'hir, V> ItemLikeVisitor<'hir> for DeepVisitor<'v, V>
 /// A parallel variant of `ItemLikeVisitor`.
 pub trait ParItemLikeVisitor<'hir> {
     fn visit_item(&self, item: &'hir Item<'hir>);
-    fn visit_trait_item(&self, trait_item: &'hir TraitItem);
+    fn visit_trait_item(&self, trait_item: &'hir TraitItem<'hir>);
     fn visit_impl_item(&self, impl_item: &'hir ImplItem);
 }
 
@@ -99,7 +99,7 @@ impl<'hir, V> ParItemLikeVisitor<'hir> for ParDeepVisitor<V>
         self.0.into_visitor().visit_item(item);
     }
 
-    fn visit_trait_item(&self, trait_item: &'hir TraitItem) {
+    fn visit_trait_item(&self, trait_item: &'hir TraitItem<'hir>) {
         self.0.into_visitor().visit_trait_item(trait_item);
     }
 
diff --git a/src/librustc/hir/lowering.rs b/src/librustc/hir/lowering.rs
index 522f9adbaef..d380b87916c 100644
--- a/src/librustc/hir/lowering.rs
+++ b/src/librustc/hir/lowering.rs
@@ -97,7 +97,7 @@ pub struct LoweringContext<'a, 'hir: 'a> {
     /// The items being lowered are collected here.
     items: BTreeMap<hir::HirId, hir::Item<'hir>>,
 
-    trait_items: BTreeMap<hir::TraitItemId, hir::TraitItem>,
+    trait_items: BTreeMap<hir::TraitItemId, hir::TraitItem<'hir>>,
     impl_items: BTreeMap<hir::ImplItemId, hir::ImplItem>,
     bodies: BTreeMap<hir::BodyId, hir::Body>,
     exported_macros: Vec<hir::MacroDef<'hir>>,
diff --git a/src/librustc/hir/lowering/item.rs b/src/librustc/hir/lowering/item.rs
index a19ddd5fd94..35a4f7cde6f 100644
--- a/src/librustc/hir/lowering/item.rs
+++ b/src/librustc/hir/lowering/item.rs
@@ -816,14 +816,14 @@ impl LoweringContext<'_, 'hir> {
         }
     }
 
-    fn lower_trait_item(&mut self, i: &AssocItem) -> hir::TraitItem {
+    fn lower_trait_item(&mut self, i: &AssocItem) -> hir::TraitItem<'hir> {
         let trait_item_def_id = self.resolver.definitions().local_def_id(i.id);
 
         let (generics, kind) = match i.kind {
             AssocItemKind::Const(ref ty, ref default) => (
                 self.lower_generics(&i.generics, ImplTraitContext::disallowed()),
                 hir::TraitItemKind::Const(
-                    self.lower_ty(ty, ImplTraitContext::disallowed()),
+                    self.arena.alloc(self.lower_ty(ty, ImplTraitContext::disallowed()).into_inner()),
                     default
                         .as_ref()
                         .map(|x| self.lower_const_body(i.span, Some(x))),
@@ -852,12 +852,13 @@ impl LoweringContext<'_, 'hir> {
                 (generics, hir::TraitItemKind::Method(sig, hir::TraitMethod::Provided(body_id)))
             }
             AssocItemKind::TyAlias(ref bounds, ref default) => {
+                let ty = default.as_ref().map(|x| -> &'hir hir::Ty { self.arena.alloc(
+                        self.lower_ty(x, ImplTraitContext::disallowed()).into_inner())
+                });
                 let generics = self.lower_generics(&i.generics, ImplTraitContext::disallowed());
                 let kind = hir::TraitItemKind::Type(
                     self.lower_param_bounds(bounds, ImplTraitContext::disallowed()),
-                    default
-                        .as_ref()
-                        .map(|x| self.lower_ty(x, ImplTraitContext::disallowed())),
+                    ty,
                 );
 
                 (generics, kind)
@@ -868,7 +869,7 @@ impl LoweringContext<'_, 'hir> {
         hir::TraitItem {
             hir_id: self.lower_node_id(i.id),
             ident: i.ident,
-            attrs: self.lower_attrs(&i.attrs),
+            attrs: self.lower_attrs_arena(&i.attrs),
             generics,
             kind,
             span: i.span,
diff --git a/src/librustc/hir/map/blocks.rs b/src/librustc/hir/map/blocks.rs
index ee2c3b9879f..a9388825f16 100644
--- a/src/librustc/hir/map/blocks.rs
+++ b/src/librustc/hir/map/blocks.rs
@@ -53,7 +53,7 @@ impl MaybeFnLike for ast::ImplItem {
     }
 }
 
-impl MaybeFnLike for ast::TraitItem {
+impl MaybeFnLike for ast::TraitItem<'_> {
     fn is_fn_like(&self) -> bool {
         match self.kind {
             ast::TraitItemKind::Method(_, ast::TraitMethod::Provided(_)) => true,
diff --git a/src/librustc/hir/map/collector.rs b/src/librustc/hir/map/collector.rs
index c29ad49aca1..95b44ba403a 100644
--- a/src/librustc/hir/map/collector.rs
+++ b/src/librustc/hir/map/collector.rs
@@ -398,7 +398,7 @@ impl<'a, 'hir> Visitor<'hir> for NodeCollector<'a, 'hir> {
         intravisit::walk_generic_param(self, param);
     }
 
-    fn visit_trait_item(&mut self, ti: &'hir TraitItem) {
+    fn visit_trait_item(&mut self, ti: &'hir TraitItem<'hir>) {
         debug_assert_eq!(ti.hir_id.owner,
                          self.definitions.opt_def_index(self.hir_to_node_id[&ti.hir_id]).unwrap());
         self.with_dep_node_owner(ti.hir_id.owner, ti, |this| {
diff --git a/src/librustc/hir/map/hir_id_validator.rs b/src/librustc/hir/map/hir_id_validator.rs
index 865b0198493..4657f8b03b0 100644
--- a/src/librustc/hir/map/hir_id_validator.rs
+++ b/src/librustc/hir/map/hir_id_validator.rs
@@ -58,7 +58,7 @@ impl<'a, 'hir> ItemLikeVisitor<'hir> for OuterVisitor<'a, 'hir> {
         inner_visitor.check(i.hir_id, |this| intravisit::walk_item(this, i));
     }
 
-    fn visit_trait_item(&mut self, i: &'hir hir::TraitItem) {
+    fn visit_trait_item(&mut self, i: &'hir hir::TraitItem<'hir>) {
         let mut inner_visitor = self.new_inner_visitor(self.hir_map);
         inner_visitor.check(i.hir_id, |this| intravisit::walk_trait_item(this, i));
     }
diff --git a/src/librustc/hir/map/mod.rs b/src/librustc/hir/map/mod.rs
index df4bc7cc817..d15d59b2210 100644
--- a/src/librustc/hir/map/mod.rs
+++ b/src/librustc/hir/map/mod.rs
@@ -443,7 +443,7 @@ impl<'hir> Map<'hir> {
         self.forest.krate()
     }
 
-    pub fn trait_item(&self, id: TraitItemId) -> &'hir TraitItem {
+    pub fn trait_item(&self, id: TraitItemId) -> &'hir TraitItem<'hir> {
         self.read(id.hir_id);
 
         // N.B., intentionally bypass `self.forest.krate()` so that we
@@ -973,7 +973,7 @@ impl<'hir> Map<'hir> {
         }
     }
 
-    pub fn expect_trait_item(&self, id: HirId) -> &'hir TraitItem {
+    pub fn expect_trait_item(&self, id: HirId) -> &'hir TraitItem<'hir> {
         match self.find(id) {
             Some(Node::TraitItem(item)) => item,
             _ => bug!("expected trait item, found {}", self.node_to_string(id))
@@ -1252,7 +1252,7 @@ impl Named for Item<'_> { fn name(&self) -> Name { self.ident.name } }
 impl Named for ForeignItem<'_> { fn name(&self) -> Name { self.ident.name } }
 impl Named for Variant { fn name(&self) -> Name { self.ident.name } }
 impl Named for StructField { fn name(&self) -> Name { self.ident.name } }
-impl Named for TraitItem { fn name(&self) -> Name { self.ident.name } }
+impl Named for TraitItem<'_> { fn name(&self) -> Name { self.ident.name } }
 impl Named for ImplItem { fn name(&self) -> Name { self.ident.name } }
 
 pub fn map_crate<'hir>(sess: &crate::session::Session,
diff --git a/src/librustc/hir/mod.rs b/src/librustc/hir/mod.rs
index d3137ee6ac1..991e51e6dc3 100644
--- a/src/librustc/hir/mod.rs
+++ b/src/librustc/hir/mod.rs
@@ -758,7 +758,7 @@ pub struct Crate<'hir> {
     // slightly different results.
     pub items: BTreeMap<HirId, Item<'hir>>,
 
-    pub trait_items: BTreeMap<TraitItemId, TraitItem>,
+    pub trait_items: BTreeMap<TraitItemId, TraitItem<'hir>>,
     pub impl_items: BTreeMap<ImplItemId, ImplItem>,
     pub bodies: BTreeMap<BodyId, Body>,
     pub trait_impls: BTreeMap<DefId, Vec<HirId>>,
@@ -779,7 +779,7 @@ impl Crate<'hir> {
         &self.items[&id]
     }
 
-    pub fn trait_item(&self, id: TraitItemId) -> &TraitItem {
+    pub fn trait_item(&self, id: TraitItemId) -> &TraitItem<'hir> {
         &self.trait_items[&id]
     }
 
@@ -1897,12 +1897,12 @@ pub struct TraitItemId {
 /// either required (meaning it doesn't have an implementation, just a
 /// signature) or provided (meaning it has a default implementation).
 #[derive(RustcEncodable, RustcDecodable, Debug)]
-pub struct TraitItem {
+pub struct TraitItem<'hir> {
     pub ident: Ident,
     pub hir_id: HirId,
-    pub attrs: HirVec<Attribute>,
+    pub attrs: &'hir [Attribute],
     pub generics: Generics,
-    pub kind: TraitItemKind,
+    pub kind: TraitItemKind<'hir>,
     pub span: Span,
 }
 
@@ -1918,14 +1918,14 @@ pub enum TraitMethod {
 
 /// Represents a trait method or associated constant or type
 #[derive(RustcEncodable, RustcDecodable, Debug, HashStable)]
-pub enum TraitItemKind {
+pub enum TraitItemKind<'hir> {
     /// An associated constant with an optional value (otherwise `impl`s must contain a value).
-    Const(P<Ty>, Option<BodyId>),
+    Const(&'hir Ty, Option<BodyId>),
     /// A method with an optional body.
     Method(FnSig, TraitMethod),
     /// An associated type with (possibly empty) bounds and optional concrete
     /// type.
-    Type(GenericBounds, Option<P<Ty>>),
+    Type(GenericBounds, Option<&'hir Ty>),
 }
 
 // The bodies for items are stored "out of line", in a separate
@@ -2789,7 +2789,7 @@ pub enum Node<'hir> {
     Param(&'hir Param),
     Item(&'hir Item<'hir>),
     ForeignItem(&'hir ForeignItem<'hir>),
-    TraitItem(&'hir TraitItem),
+    TraitItem(&'hir TraitItem<'hir>),
     ImplItem(&'hir ImplItem),
     Variant(&'hir Variant),
     Field(&'hir StructField),
diff --git a/src/librustc/hir/print.rs b/src/librustc/hir/print.rs
index b6f7f840d08..d24d08575e7 100644
--- a/src/librustc/hir/print.rs
+++ b/src/librustc/hir/print.rs
@@ -846,7 +846,7 @@ impl<'a> State<'a> {
                       body_id)
     }
 
-    pub fn print_trait_item(&mut self, ti: &hir::TraitItem) {
+    pub fn print_trait_item(&mut self, ti: &hir::TraitItem<'_>) {
         self.ann.pre(self, AnnNode::SubItem(ti.hir_id));
         self.hardbreak_if_not_bol();
         self.maybe_print_comment(ti.span.lo());
diff --git a/src/librustc/ich/impls_hir.rs b/src/librustc/ich/impls_hir.rs
index f2e893ec055..149e647ca74 100644
--- a/src/librustc/ich/impls_hir.rs
+++ b/src/librustc/ich/impls_hir.rs
@@ -150,7 +150,7 @@ impl<'a> HashStable<StableHashingContext<'a>> for hir::Expr {
     }
 }
 
-impl<'a> HashStable<StableHashingContext<'a>> for hir::TraitItem {
+impl<'a> HashStable<StableHashingContext<'a>> for hir::TraitItem<'_> {
     fn hash_stable(&self, hcx: &mut StableHashingContext<'a>, hasher: &mut StableHasher) {
         let hir::TraitItem {
             hir_id: _,
diff --git a/src/librustc/infer/error_reporting/mod.rs b/src/librustc/infer/error_reporting/mod.rs
index 1a1c718e55a..f5e52c4d4b2 100644
--- a/src/librustc/infer/error_reporting/mod.rs
+++ b/src/librustc/infer/error_reporting/mod.rs
@@ -264,7 +264,7 @@ impl<'tcx> TyCtxt<'tcx> {
         }
     }
 
-    fn trait_item_scope_tag(item: &hir::TraitItem) -> &'static str {
+    fn trait_item_scope_tag(item: &hir::TraitItem<'_>) -> &'static str {
         match item.kind {
             hir::TraitItemKind::Method(..) => "method body",
             hir::TraitItemKind::Const(..) | hir::TraitItemKind::Type(..) => "associated item",
diff --git a/src/librustc/lint/context.rs b/src/librustc/lint/context.rs
index c3cd50b4885..8327977d9b0 100644
--- a/src/librustc/lint/context.rs
+++ b/src/librustc/lint/context.rs
@@ -1072,7 +1072,7 @@ for LateContextAndPass<'a, 'tcx, T> {
         hir_visit::walk_poly_trait_ref(self, t, m);
     }
 
-    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
         let generics = self.context.generics.take();
         self.context.generics = Some(&trait_item.generics);
         self.with_lint_attrs(trait_item.hir_id, &trait_item.attrs, |cx| {
diff --git a/src/librustc/lint/mod.rs b/src/librustc/lint/mod.rs
index 79fb53c92b0..3dad72543f5 100644
--- a/src/librustc/lint/mod.rs
+++ b/src/librustc/lint/mod.rs
@@ -124,8 +124,8 @@ macro_rules! late_lint_methods {
                 d: Span,
                 e: hir::HirId
             );
-            fn check_trait_item(a: &$hir hir::TraitItem);
-            fn check_trait_item_post(a: &$hir hir::TraitItem);
+            fn check_trait_item(a: &$hir hir::TraitItem<$hir>);
+            fn check_trait_item_post(a: &$hir hir::TraitItem<$hir>);
             fn check_impl_item(a: &$hir hir::ImplItem);
             fn check_impl_item_post(a: &$hir hir::ImplItem);
             fn check_struct_def(a: &$hir hir::VariantData);
@@ -649,7 +649,7 @@ impl intravisit::Visitor<'tcx> for LintLevelMapBuilder<'_, 'tcx> {
         })
     }
 
-    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
         self.with_lint_attrs(trait_item.hir_id, &trait_item.attrs, |builder| {
             intravisit::walk_trait_item(builder, trait_item);
         });
diff --git a/src/librustc/middle/diagnostic_items.rs b/src/librustc/middle/diagnostic_items.rs
index 57b1f09626f..466c7a37d0f 100644
--- a/src/librustc/middle/diagnostic_items.rs
+++ b/src/librustc/middle/diagnostic_items.rs
@@ -29,7 +29,7 @@ impl<'v, 'tcx> ItemLikeVisitor<'v> for DiagnosticItemCollector<'tcx> {
         self.observe_item(&item.attrs, item.hir_id);
     }
 
-    fn visit_trait_item(&mut self, trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &hir::TraitItem<'_>) {
         self.observe_item(&trait_item.attrs, trait_item.hir_id);
     }
 
diff --git a/src/librustc/middle/lang_items.rs b/src/librustc/middle/lang_items.rs
index cfb54b15b3b..dadc9261a3e 100644
--- a/src/librustc/middle/lang_items.rs
+++ b/src/librustc/middle/lang_items.rs
@@ -151,7 +151,7 @@ impl ItemLikeVisitor<'v> for LanguageItemCollector<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {
         // At present, lang items are always items, not trait items.
     }
 
diff --git a/src/librustc/middle/reachable.rs b/src/librustc/middle/reachable.rs
index 9f045a59df6..643c92185c8 100644
--- a/src/librustc/middle/reachable.rs
+++ b/src/librustc/middle/reachable.rs
@@ -387,7 +387,7 @@ impl<'a, 'tcx> ItemLikeVisitor<'tcx> for CollectPrivateImplItemsVisitor<'a, 'tcx
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {}
+    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {}
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
         // processed in visit_item above
diff --git a/src/librustc/middle/resolve_lifetime.rs b/src/librustc/middle/resolve_lifetime.rs
index 7a852ef9ef4..c6a4a926ae4 100644
--- a/src/librustc/middle/resolve_lifetime.rs
+++ b/src/librustc/middle/resolve_lifetime.rs
@@ -771,7 +771,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
         use self::hir::TraitItemKind::*;
         match trait_item.kind {
             Method(ref sig, _) => {
diff --git a/src/librustc/middle/stability.rs b/src/librustc/middle/stability.rs
index 27830c86ed1..03c6abfbb84 100644
--- a/src/librustc/middle/stability.rs
+++ b/src/librustc/middle/stability.rs
@@ -283,7 +283,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Annotator<'a, 'tcx> {
         self.in_trait_impl = orig_in_trait_impl;
     }
 
-    fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem<'tcx>) {
         self.annotate(ti.hir_id, &ti.attrs, ti.span, AnnotationKind::Required, |v| {
             intravisit::walk_trait_item(v, ti);
         });
@@ -368,7 +368,7 @@ impl<'a, 'tcx> Visitor<'tcx> for MissingStabilityAnnotations<'a, 'tcx> {
         intravisit::walk_item(self, i)
     }
 
-    fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem<'tcx>) {
         self.check_missing_stability(ti.hir_id, ti.span, "item");
         intravisit::walk_trait_item(self, ti);
     }
diff --git a/src/librustc_codegen_utils/symbol_names_test.rs b/src/librustc_codegen_utils/symbol_names_test.rs
index d468717fe7c..1a21be66c43 100644
--- a/src/librustc_codegen_utils/symbol_names_test.rs
+++ b/src/librustc_codegen_utils/symbol_names_test.rs
@@ -61,7 +61,7 @@ impl hir::itemlikevisit::ItemLikeVisitor<'tcx> for SymbolNamesTest<'tcx> {
         self.process_attrs(item.hir_id);
     }
 
-    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
         self.process_attrs(trait_item.hir_id);
     }
 
diff --git a/src/librustc_incremental/assert_dep_graph.rs b/src/librustc_incremental/assert_dep_graph.rs
index 8b016b12550..db64e736a5c 100644
--- a/src/librustc_incremental/assert_dep_graph.rs
+++ b/src/librustc_incremental/assert_dep_graph.rs
@@ -167,7 +167,7 @@ impl Visitor<'tcx> for IfThisChanged<'tcx> {
         intravisit::walk_item(self, item);
     }
 
-    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
         self.process_attrs(trait_item.hir_id, &trait_item.attrs);
         intravisit::walk_trait_item(self, trait_item);
     }
diff --git a/src/librustc_incremental/persist/dirty_clean.rs b/src/librustc_incremental/persist/dirty_clean.rs
index adb67b84087..b8f58ca2e91 100644
--- a/src/librustc_incremental/persist/dirty_clean.rs
+++ b/src/librustc_incremental/persist/dirty_clean.rs
@@ -536,7 +536,7 @@ impl ItemLikeVisitor<'tcx> for DirtyCleanVisitor<'tcx> {
         self.check_item(item.hir_id, item.span);
     }
 
-    fn visit_trait_item(&mut self, item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, item: &hir::TraitItem<'_>) {
         self.check_item(item.hir_id, item.span);
     }
 
diff --git a/src/librustc_interface/proc_macro_decls.rs b/src/librustc_interface/proc_macro_decls.rs
index 9c2e8a3d47e..c13dd595834 100644
--- a/src/librustc_interface/proc_macro_decls.rs
+++ b/src/librustc_interface/proc_macro_decls.rs
@@ -30,7 +30,7 @@ impl<'v> ItemLikeVisitor<'v> for Finder {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {
     }
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
diff --git a/src/librustc_lint/builtin.rs b/src/librustc_lint/builtin.rs
index 030fb8dc339..0a38ca55a24 100644
--- a/src/librustc_lint/builtin.rs
+++ b/src/librustc_lint/builtin.rs
@@ -436,7 +436,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MissingDoc {
         self.check_missing_docs_attrs(cx, Some(it.hir_id), &it.attrs, it.span, desc);
     }
 
-    fn check_trait_item(&mut self, cx: &LateContext<'_, '_>, trait_item: &hir::TraitItem) {
+    fn check_trait_item(&mut self, cx: &LateContext<'_, '_>, trait_item: &hir::TraitItem<'_>) {
         if self.private_traits.contains(&trait_item.hir_id) {
             return;
         }
diff --git a/src/librustc_lint/nonstandard_style.rs b/src/librustc_lint/nonstandard_style.rs
index 7235321b2b3..e4805f1217b 100644
--- a/src/librustc_lint/nonstandard_style.rs
+++ b/src/librustc_lint/nonstandard_style.rs
@@ -331,7 +331,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for NonSnakeCase {
         }
     }
 
-    fn check_trait_item(&mut self, cx: &LateContext<'_, '_>, item: &hir::TraitItem) {
+    fn check_trait_item(&mut self, cx: &LateContext<'_, '_>, item: &hir::TraitItem<'_>) {
         if let hir::TraitItemKind::Method(_, hir::TraitMethod::Required(pnames)) = &item.kind {
             self.check_snake_case(cx, "trait method", &item.ident);
             for param_name in pnames {
@@ -398,7 +398,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for NonUpperCaseGlobals {
         }
     }
 
-    fn check_trait_item(&mut self, cx: &LateContext<'_, '_>, ti: &hir::TraitItem) {
+    fn check_trait_item(&mut self, cx: &LateContext<'_, '_>, ti: &hir::TraitItem<'_>) {
         if let hir::TraitItemKind::Const(..) = ti.kind {
             NonUpperCaseGlobals::check_upper_case(cx, "associated constant", &ti.ident);
         }
diff --git a/src/librustc_metadata/foreign_modules.rs b/src/librustc_metadata/foreign_modules.rs
index acfcdd9a87f..14f83642f9c 100644
--- a/src/librustc_metadata/foreign_modules.rs
+++ b/src/librustc_metadata/foreign_modules.rs
@@ -33,6 +33,6 @@ impl ItemLikeVisitor<'tcx> for Collector<'tcx> {
         });
     }
 
-    fn visit_trait_item(&mut self, _it: &'tcx hir::TraitItem) {}
+    fn visit_trait_item(&mut self, _it: &'tcx hir::TraitItem<'tcx>) {}
     fn visit_impl_item(&mut self, _it: &'tcx hir::ImplItem) {}
 }
diff --git a/src/librustc_metadata/link_args.rs b/src/librustc_metadata/link_args.rs
index 2283b772ea8..2fb0790cb46 100644
--- a/src/librustc_metadata/link_args.rs
+++ b/src/librustc_metadata/link_args.rs
@@ -45,7 +45,7 @@ impl<'tcx> ItemLikeVisitor<'tcx> for Collector {
         }
     }
 
-    fn visit_trait_item(&mut self, _it: &'tcx hir::TraitItem) {}
+    fn visit_trait_item(&mut self, _it: &'tcx hir::TraitItem<'tcx>) {}
     fn visit_impl_item(&mut self, _it: &'tcx hir::ImplItem) {}
 }
 
diff --git a/src/librustc_metadata/native_libs.rs b/src/librustc_metadata/native_libs.rs
index c9c3be46101..d8230b67037 100644
--- a/src/librustc_metadata/native_libs.rs
+++ b/src/librustc_metadata/native_libs.rs
@@ -129,7 +129,7 @@ impl ItemLikeVisitor<'tcx> for Collector<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _it: &'tcx hir::TraitItem) {}
+    fn visit_trait_item(&mut self, _it: &'tcx hir::TraitItem<'tcx>) {}
     fn visit_impl_item(&mut self, _it: &'tcx hir::ImplItem) {}
 }
 
diff --git a/src/librustc_metadata/rmeta/encoder.rs b/src/librustc_metadata/rmeta/encoder.rs
index 93e04c18f5f..0f168ff906f 100644
--- a/src/librustc_metadata/rmeta/encoder.rs
+++ b/src/librustc_metadata/rmeta/encoder.rs
@@ -864,7 +864,7 @@ impl EncodeContext<'tcx> {
         });
         record!(self.per_def.visibility[def_id] <- trait_item.vis);
         record!(self.per_def.span[def_id] <- ast_item.span);
-        record!(self.per_def.attributes[def_id] <- &ast_item.attrs);
+        record!(self.per_def.attributes[def_id] <- ast_item.attrs);
         self.encode_stability(def_id);
         self.encode_const_stability(def_id);
         self.encode_deprecation(def_id);
@@ -1725,7 +1725,7 @@ impl<'tcx, 'v> ItemLikeVisitor<'v> for ImplVisitor<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &'v hir::TraitItem) {}
+    fn visit_trait_item(&mut self, _trait_item: &'v hir::TraitItem<'v>) {}
 
     fn visit_impl_item(&mut self, _impl_item: &'v hir::ImplItem) {
         // handled in `visit_item` above
diff --git a/src/librustc_mir/build/mod.rs b/src/librustc_mir/build/mod.rs
index df8e2b21285..9645607e5ac 100644
--- a/src/librustc_mir/build/mod.rs
+++ b/src/librustc_mir/build/mod.rs
@@ -59,7 +59,10 @@ pub fn mir_build(tcx: TyCtxt<'_>, def_id: DefId) -> BodyAndCache<'_> {
             (*body_id, ty.span)
         }
         | Node::ImplItem(hir::ImplItem { kind: hir::ImplItemKind::Const(ty, body_id), .. })
-        | Node::TraitItem(
+        => {
+            (*body_id, ty.span)
+        }
+        Node::TraitItem(
             hir::TraitItem { kind: hir::TraitItemKind::Const(ty, Some(body_id)), .. }
         ) => {
             (*body_id, ty.span)
diff --git a/src/librustc_mir/monomorphize/collector.rs b/src/librustc_mir/monomorphize/collector.rs
index d2b18ae0103..18b811be465 100644
--- a/src/librustc_mir/monomorphize/collector.rs
+++ b/src/librustc_mir/monomorphize/collector.rs
@@ -1059,7 +1059,7 @@ impl ItemLikeVisitor<'v> for RootCollector<'_, 'v> {
         }
     }
 
-    fn visit_trait_item(&mut self, _: &'v hir::TraitItem) {
+    fn visit_trait_item(&mut self, _: &'v hir::TraitItem<'v>) {
         // Even if there's a default body with no explicit generics,
         // it's still generic over some `Self: Trait`, so not a root.
     }
diff --git a/src/librustc_passes/dead.rs b/src/librustc_passes/dead.rs
index ee67e44afc8..b36db76c7df 100644
--- a/src/librustc_passes/dead.rs
+++ b/src/librustc_passes/dead.rs
@@ -417,7 +417,7 @@ impl<'v, 'k, 'tcx> ItemLikeVisitor<'v> for LifeSeeder<'k, 'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, _item: &hir::TraitItem<'_>) {
         // ignore: we are handling this in `visit_item` above
     }
 
@@ -662,7 +662,7 @@ impl Visitor<'tcx> for DeadVisitor<'tcx> {
     }
 
     // Overwrite so that we don't warn the trait item itself.
-    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
         match trait_item.kind {
             hir::TraitItemKind::Const(_, Some(body_id)) |
             hir::TraitItemKind::Method(_, hir::TraitMethod::Provided(body_id)) => {
diff --git a/src/librustc_passes/entry.rs b/src/librustc_passes/entry.rs
index 89c1cc8e6b4..ad9a924d5d3 100644
--- a/src/librustc_passes/entry.rs
+++ b/src/librustc_passes/entry.rs
@@ -40,7 +40,7 @@ impl<'a, 'tcx> ItemLikeVisitor<'tcx> for EntryContext<'a, 'tcx> {
         find_item(item, self, at_root);
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &'tcx TraitItem) {
+    fn visit_trait_item(&mut self, _trait_item: &'tcx TraitItem<'tcx>) {
         // Entry fn is never a trait item.
     }
 
diff --git a/src/librustc_passes/hir_stats.rs b/src/librustc_passes/hir_stats.rs
index 4cde255fc83..5598613e5c9 100644
--- a/src/librustc_passes/hir_stats.rs
+++ b/src/librustc_passes/hir_stats.rs
@@ -188,7 +188,7 @@ impl<'v> hir_visit::Visitor<'v> for StatCollector<'v> {
         hir_visit::walk_where_predicate(self, predicate)
     }
 
-    fn visit_trait_item(&mut self, ti: &'v hir::TraitItem) {
+    fn visit_trait_item(&mut self, ti: &'v hir::TraitItem<'v>) {
         self.record("TraitItem", Id::Node(ti.hir_id), ti);
         hir_visit::walk_trait_item(self, ti)
     }
diff --git a/src/librustc_passes/layout_test.rs b/src/librustc_passes/layout_test.rs
index 0e0725ccd67..24b6753c0c7 100644
--- a/src/librustc_passes/layout_test.rs
+++ b/src/librustc_passes/layout_test.rs
@@ -40,7 +40,7 @@ impl ItemLikeVisitor<'tcx> for VarianceTest<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem) {}
+    fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem<'tcx>) {}
     fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem) {}
 }
 
diff --git a/src/librustc_plugin_impl/build.rs b/src/librustc_plugin_impl/build.rs
index 02e2266d8f4..6da3e872628 100644
--- a/src/librustc_plugin_impl/build.rs
+++ b/src/librustc_plugin_impl/build.rs
@@ -22,7 +22,7 @@ impl<'v> ItemLikeVisitor<'v> for RegistrarFinder {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {
     }
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
diff --git a/src/librustc_privacy/lib.rs b/src/librustc_privacy/lib.rs
index 5963561c5bb..b7c06609fa3 100644
--- a/src/librustc_privacy/lib.rs
+++ b/src/librustc_privacy/lib.rs
@@ -1013,7 +1013,7 @@ impl<'a, 'tcx> Visitor<'tcx> for NamePrivacyVisitor<'a, 'tcx> {
         self.tables = orig_tables;
     }
 
-    fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem<'tcx>) {
         let orig_tables =
             mem::replace(&mut self.tables, item_tables(self.tcx, ti.hir_id, self.empty_tables));
         intravisit::walk_trait_item(self, ti);
@@ -1295,7 +1295,7 @@ impl<'a, 'tcx> Visitor<'tcx> for TypePrivacyVisitor<'a, 'tcx> {
         self.current_item = orig_current_item;
     }
 
-    fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, ti: &'tcx hir::TraitItem<'tcx>) {
         let orig_tables =
             mem::replace(&mut self.tables, item_tables(self.tcx, ti.hir_id, self.empty_tables));
         intravisit::walk_trait_item(self, ti);
diff --git a/src/librustc_traits/lowering/mod.rs b/src/librustc_traits/lowering/mod.rs
index ecd3112cd79..1f5958ef8fb 100644
--- a/src/librustc_traits/lowering/mod.rs
+++ b/src/librustc_traits/lowering/mod.rs
@@ -674,7 +674,7 @@ impl Visitor<'tcx> for ClauseDumper<'tcx> {
         intravisit::walk_item(self, item);
     }
 
-    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
         self.process_attrs(trait_item.hir_id, &trait_item.attrs);
         intravisit::walk_trait_item(self, trait_item);
     }
diff --git a/src/librustc_typeck/check/method/suggest.rs b/src/librustc_typeck/check/method/suggest.rs
index 99525cc30fd..3c6e6d974d9 100644
--- a/src/librustc_typeck/check/method/suggest.rs
+++ b/src/librustc_typeck/check/method/suggest.rs
@@ -1013,7 +1013,7 @@ fn compute_all_traits(tcx: TyCtxt<'_>) -> Vec<DefId> {
             }
         }
 
-        fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {}
+        fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {}
 
         fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {}
     }
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index 4c83ee1c644..ce5a385b587 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -754,7 +754,7 @@ impl ItemLikeVisitor<'tcx> for CheckItemTypesVisitor<'tcx> {
     fn visit_item(&mut self, i: &'tcx hir::Item<'tcx>) {
         check_item_type(self.tcx, i);
     }
-    fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem) { }
+    fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem<'tcx>) { }
     fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem) { }
 }
 
diff --git a/src/librustc_typeck/check/wfcheck.rs b/src/librustc_typeck/check/wfcheck.rs
index 9e69b0a2908..207db48860f 100644
--- a/src/librustc_typeck/check/wfcheck.rs
+++ b/src/librustc_typeck/check/wfcheck.rs
@@ -1087,7 +1087,7 @@ impl ParItemLikeVisitor<'tcx> for CheckTypeWellFormedVisitor<'tcx> {
         self.tcx.ensure().check_item_well_formed(def_id);
     }
 
-    fn visit_trait_item(&self, trait_item: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&self, trait_item: &'tcx hir::TraitItem<'tcx>) {
         debug!("visit_trait_item: {:?}", trait_item);
         let def_id = self.tcx.hir().local_def_id(trait_item.hir_id);
         self.tcx.ensure().check_trait_item_well_formed(def_id);
diff --git a/src/librustc_typeck/check_unused.rs b/src/librustc_typeck/check_unused.rs
index bbb743cd3c7..950954a66ef 100644
--- a/src/librustc_typeck/check_unused.rs
+++ b/src/librustc_typeck/check_unused.rs
@@ -38,7 +38,7 @@ impl ItemLikeVisitor<'v> for CheckVisitor<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {
     }
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
@@ -231,7 +231,7 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for CollectExternCrateVisitor<'a, 'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {
     }
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
diff --git a/src/librustc_typeck/coherence/inherent_impls.rs b/src/librustc_typeck/coherence/inherent_impls.rs
index 13af3865225..2e4c25cf0df 100644
--- a/src/librustc_typeck/coherence/inherent_impls.rs
+++ b/src/librustc_typeck/coherence/inherent_impls.rs
@@ -254,7 +254,7 @@ impl ItemLikeVisitor<'v> for InherentCollect<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {
     }
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
diff --git a/src/librustc_typeck/coherence/inherent_impls_overlap.rs b/src/librustc_typeck/coherence/inherent_impls_overlap.rs
index 84ae0b296a1..11bd0209c0d 100644
--- a/src/librustc_typeck/coherence/inherent_impls_overlap.rs
+++ b/src/librustc_typeck/coherence/inherent_impls_overlap.rs
@@ -98,7 +98,7 @@ impl ItemLikeVisitor<'v> for InherentOverlapChecker<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'v>) {
     }
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
diff --git a/src/librustc_typeck/coherence/orphan.rs b/src/librustc_typeck/coherence/orphan.rs
index 17487244ee7..85e5dad0ccd 100644
--- a/src/librustc_typeck/coherence/orphan.rs
+++ b/src/librustc_typeck/coherence/orphan.rs
@@ -218,7 +218,7 @@ impl ItemLikeVisitor<'v> for OrphanChecker<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {
     }
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
diff --git a/src/librustc_typeck/coherence/unsafety.rs b/src/librustc_typeck/coherence/unsafety.rs
index 5335253f5d6..0a7c907fe5d 100644
--- a/src/librustc_typeck/coherence/unsafety.rs
+++ b/src/librustc_typeck/coherence/unsafety.rs
@@ -78,7 +78,7 @@ impl ItemLikeVisitor<'v> for UnsafetyChecker<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, _trait_item: &hir::TraitItem<'_>) {
     }
 
     fn visit_impl_item(&mut self, _impl_item: &hir::ImplItem) {
diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs
index 02831784c96..c09d56b3984 100644
--- a/src/librustc_typeck/collect.rs
+++ b/src/librustc_typeck/collect.rs
@@ -145,7 +145,7 @@ impl Visitor<'tcx> for CollectItemTypesVisitor<'tcx> {
         intravisit::walk_expr(self, expr);
     }
 
-    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &'tcx hir::TraitItem<'tcx>) {
         convert_trait_item(self.tcx, trait_item.hir_id);
         intravisit::walk_trait_item(self, trait_item);
     }
@@ -1711,7 +1711,7 @@ fn find_opaque_ty_constraints(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
                 intravisit::walk_impl_item(self, it);
             }
         }
-        fn visit_trait_item(&mut self, it: &'tcx TraitItem) {
+        fn visit_trait_item(&mut self, it: &'tcx TraitItem<'tcx>) {
             debug!("find_existential_constraints: visiting {:?}", it);
             let def_id = self.tcx.hir().local_def_id(it.hir_id);
             self.check(def_id);
diff --git a/src/librustc_typeck/impl_wf_check.rs b/src/librustc_typeck/impl_wf_check.rs
index 98438945d11..b7691189865 100644
--- a/src/librustc_typeck/impl_wf_check.rs
+++ b/src/librustc_typeck/impl_wf_check.rs
@@ -89,7 +89,7 @@ impl ItemLikeVisitor<'tcx> for ImplWfCheck<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &'tcx hir::TraitItem) { }
+    fn visit_trait_item(&mut self, _trait_item: &'tcx hir::TraitItem<'tcx>) { }
 
     fn visit_impl_item(&mut self, _impl_item: &'tcx hir::ImplItem) { }
 }
diff --git a/src/librustc_typeck/outlives/implicit_infer.rs b/src/librustc_typeck/outlives/implicit_infer.rs
index 4ed631232b4..edf83b1de1d 100644
--- a/src/librustc_typeck/outlives/implicit_infer.rs
+++ b/src/librustc_typeck/outlives/implicit_infer.rs
@@ -113,7 +113,7 @@ impl<'cx, 'tcx> ItemLikeVisitor<'tcx> for InferVisitor<'cx, 'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _trait_item: &'tcx hir::TraitItem) {}
+    fn visit_trait_item(&mut self, _trait_item: &'tcx hir::TraitItem<'tcx>) {}
 
     fn visit_impl_item(&mut self, _impl_item: &'tcx hir::ImplItem) {}
 }
diff --git a/src/librustc_typeck/outlives/test.rs b/src/librustc_typeck/outlives/test.rs
index 86f61158f5f..a8c4f9c0ebb 100644
--- a/src/librustc_typeck/outlives/test.rs
+++ b/src/librustc_typeck/outlives/test.rs
@@ -33,6 +33,6 @@ impl ItemLikeVisitor<'tcx> for OutlivesTest<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem) {}
+    fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem<'tcx>) {}
     fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem) {}
 }
diff --git a/src/librustc_typeck/variance/constraints.rs b/src/librustc_typeck/variance/constraints.rs
index d15d8d09df7..ff29c3ca4bd 100644
--- a/src/librustc_typeck/variance/constraints.rs
+++ b/src/librustc_typeck/variance/constraints.rs
@@ -104,7 +104,7 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for ConstraintContext<'a, 'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &hir::TraitItem<'_>) {
         if let hir::TraitItemKind::Method(..) = trait_item.kind {
             self.visit_node_helper(trait_item.hir_id);
         }
diff --git a/src/librustc_typeck/variance/terms.rs b/src/librustc_typeck/variance/terms.rs
index 7567bb791fa..4de16e71553 100644
--- a/src/librustc_typeck/variance/terms.rs
+++ b/src/librustc_typeck/variance/terms.rs
@@ -167,7 +167,7 @@ impl<'a, 'tcx, 'v> ItemLikeVisitor<'v> for TermsContext<'a, 'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, trait_item: &hir::TraitItem) {
+    fn visit_trait_item(&mut self, trait_item: &hir::TraitItem<'_>) {
         if let hir::TraitItemKind::Method(..) = trait_item.kind {
             self.add_inferreds_for_item(trait_item.hir_id);
         }
diff --git a/src/librustc_typeck/variance/test.rs b/src/librustc_typeck/variance/test.rs
index 01088db0efb..416cb91c232 100644
--- a/src/librustc_typeck/variance/test.rs
+++ b/src/librustc_typeck/variance/test.rs
@@ -29,6 +29,6 @@ impl ItemLikeVisitor<'tcx> for VarianceTest<'tcx> {
         }
     }
 
-    fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem) { }
+    fn visit_trait_item(&mut self, _: &'tcx hir::TraitItem<'tcx>) { }
     fn visit_impl_item(&mut self, _: &'tcx hir::ImplItem) { }
 }
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index cebfd99452a..5dd82689369 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -70,6 +70,12 @@ impl<T: Clean<U>, U, V: Idx> Clean<IndexVec<V, U>> for IndexVec<V, T> {
     }
 }
 
+impl<T: Clean<U>, U> Clean<U> for &T {
+    fn clean(&self, cx: &DocContext<'_>) -> U {
+        (**self).clean(cx)
+    }
+}
+
 impl<T: Clean<U>, U> Clean<U> for P<T> {
     fn clean(&self, cx: &DocContext<'_>) -> U {
         (**self).clean(cx)
@@ -1080,7 +1086,7 @@ impl Clean<PolyTrait> for hir::PolyTraitRef {
     }
 }
 
-impl Clean<Item> for hir::TraitItem {
+impl Clean<Item> for hir::TraitItem<'_> {
     fn clean(&self, cx: &DocContext<'_>) -> Item {
         let inner = match self.kind {
             hir::TraitItemKind::Const(ref ty, default) => {
@@ -2386,12 +2392,6 @@ impl Clean<Stability> for attr::Stability {
     }
 }
 
-impl<'a> Clean<Stability> for &'a attr::Stability {
-    fn clean(&self, dc: &DocContext<'_>) -> Stability {
-        (**self).clean(dc)
-    }
-}
-
 impl Clean<Deprecation> for attr::Deprecation {
     fn clean(&self, _: &DocContext<'_>) -> Deprecation {
         Deprecation {
diff --git a/src/librustdoc/doctree.rs b/src/librustdoc/doctree.rs
index 57208bd5966..f5de869cf13 100644
--- a/src/librustdoc/doctree.rs
+++ b/src/librustdoc/doctree.rs
@@ -179,7 +179,7 @@ pub struct Trait<'hir> {
     pub is_auto: hir::IsAuto,
     pub unsafety: hir::Unsafety,
     pub name: Name,
-    pub items: Vec<&'hir hir::TraitItem>,
+    pub items: Vec<&'hir hir::TraitItem<'hir>>,
     pub generics: &'hir hir::Generics,
     pub bounds: &'hir [hir::GenericBound],
     pub attrs: &'hir [ast::Attribute],