diff --git a/src/libcore/convert.rs b/src/libcore/convert.rs
index 06f2b7bab12eb..3cd2337ee59a5 100644
--- a/src/libcore/convert.rs
+++ b/src/libcore/convert.rs
@@ -554,6 +554,18 @@ impl<T> From<T> for T {
     fn from(t: T) -> T { t }
 }
 
+/// **Stability note:** This impl does not yet exist, but we are
+/// "reserving space" to add it in the future. See
+/// [rust-lang/rust#64715][#64715] for details.
+///
+/// [#64715]: https://github.com/rust-lang/rust/issues/64715
+#[stable(feature = "convert_infallible", since = "1.34.0")]
+#[cfg(not(bootstrap))]
+#[rustc_reservation_impl="permitting this impl would forbid us from adding \
+`impl<T> From<!> for T` later; see rust-lang/rust#64715 for details"]
+impl<T> From<!> for T {
+    fn from(t: !) -> T { t }
+}
 
 // TryFrom implies TryInto
 #[stable(feature = "try_from", since = "1.34.0")]
diff --git a/src/librustc/infer/canonical/canonicalizer.rs b/src/librustc/infer/canonical/canonicalizer.rs
index db724875b8aa3..bd003735a892c 100644
--- a/src/librustc/infer/canonical/canonicalizer.rs
+++ b/src/librustc/infer/canonical/canonicalizer.rs
@@ -343,7 +343,7 @@ impl<'cx, 'tcx> TypeFolder<'tcx> for Canonicalizer<'cx, 'tcx> {
     }
 
     fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
-        match t.sty {
+        match t.kind {
             ty::Infer(ty::TyVar(vid)) => {
                 debug!("canonical: type var found with vid {:?}", vid);
                 match self.infcx.unwrap().probe_ty_var(vid) {
diff --git a/src/librustc/infer/canonical/query_response.rs b/src/librustc/infer/canonical/query_response.rs
index 79c5538626be1..ae1624fc5a242 100644
--- a/src/librustc/infer/canonical/query_response.rs
+++ b/src/librustc/infer/canonical/query_response.rs
@@ -471,7 +471,7 @@ impl<'cx, 'tcx> InferCtxt<'cx, 'tcx> {
             match result_value.unpack() {
                 UnpackedKind::Type(result_value) => {
                     // e.g., here `result_value` might be `?0` in the example above...
-                    if let ty::Bound(debruijn, b) = result_value.sty {
+                    if let ty::Bound(debruijn, b) = result_value.kind {
                         // ...in which case we would set `canonical_vars[0]` to `Some(?U)`.
 
                         // We only allow a `ty::INNERMOST` index in substitutions.
diff --git a/src/librustc/infer/combine.rs b/src/librustc/infer/combine.rs
index 966c5810171af..6f73275d455f5 100644
--- a/src/librustc/infer/combine.rs
+++ b/src/librustc/infer/combine.rs
@@ -70,7 +70,7 @@ impl<'infcx, 'tcx> InferCtxt<'infcx, 'tcx> {
     {
         let a_is_expected = relation.a_is_expected();
 
-        match (&a.sty, &b.sty) {
+        match (&a.kind, &b.kind) {
             // Relate integral variables to other types
             (&ty::Infer(ty::IntVar(a_id)), &ty::Infer(ty::IntVar(b_id))) => {
                 self.int_unification_table
@@ -486,7 +486,7 @@ impl TypeRelation<'tcx> for Generalizer<'_, 'tcx> {
         // any other type variable related to `vid` via
         // subtyping. This is basically our "occurs check", preventing
         // us from creating infinitely sized types.
-        match t.sty {
+        match t.kind {
             ty::Infer(ty::TyVar(vid)) => {
                 let mut variables = self.infcx.type_variables.borrow_mut();
                 let vid = variables.root_var(vid);
diff --git a/src/librustc/infer/equate.rs b/src/librustc/infer/equate.rs
index 6065387647fa7..aea58acab5450 100644
--- a/src/librustc/infer/equate.rs
+++ b/src/librustc/infer/equate.rs
@@ -68,7 +68,7 @@ impl TypeRelation<'tcx> for Equate<'combine, 'infcx, 'tcx> {
 
         debug!("{}.tys: replacements ({:?}, {:?})", self.tag(), a, b);
 
-        match (&a.sty, &b.sty) {
+        match (&a.kind, &b.kind) {
             (&ty::Infer(TyVar(a_id)), &ty::Infer(TyVar(b_id))) => {
                 infcx.type_variables.borrow_mut().equate(a_id, b_id);
             }
diff --git a/src/librustc/infer/error_reporting/mod.rs b/src/librustc/infer/error_reporting/mod.rs
index 0b6740d7bbbc8..15a664cb33b6f 100644
--- a/src/librustc/infer/error_reporting/mod.rs
+++ b/src/librustc/infer/error_reporting/mod.rs
@@ -589,7 +589,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                 // if they are both "path types", there's a chance of ambiguity
                 // due to different versions of the same crate
                 if let (&ty::Adt(exp_adt, _), &ty::Adt(found_adt, _))
-                     = (&exp_found.expected.sty, &exp_found.found.sty)
+                     = (&exp_found.expected.kind, &exp_found.found.kind)
                 {
                     report_path_match(err, exp_adt.did, found_adt.did);
                 }
@@ -803,7 +803,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                 self.highlight_outer(&mut t1_out, &mut t2_out, path, sub, i, &other_ty);
                 return Some(());
             }
-            if let &ty::Adt(def, _) = &ta.sty {
+            if let &ty::Adt(def, _) = &ta.kind {
                 let path_ = self.tcx.def_path_str(def.did.clone());
                 if path_ == other_path {
                     self.highlight_outer(&mut t1_out, &mut t2_out, path, sub, i, &other_ty);
@@ -868,7 +868,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
     /// relevant differences, and return two representation of those types for highlighted printing.
     fn cmp(&self, t1: Ty<'tcx>, t2: Ty<'tcx>) -> (DiagnosticStyledString, DiagnosticStyledString) {
         fn equals<'tcx>(a: Ty<'tcx>, b: Ty<'tcx>) -> bool {
-            match (&a.sty, &b.sty) {
+            match (&a.kind, &b.kind) {
                 (a, b) if *a == *b => true,
                 (&ty::Int(_), &ty::Infer(ty::InferTy::IntVar(_)))
                 | (&ty::Infer(ty::InferTy::IntVar(_)), &ty::Int(_))
@@ -902,7 +902,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             s.push_normal(ty.to_string());
         }
 
-        match (&t1.sty, &t2.sty) {
+        match (&t1.kind, &t2.kind) {
             (&ty::Adt(def1, sub1), &ty::Adt(def2, sub2)) => {
                 let sub_no_defaults_1 = self.strip_generic_default_params(def1.did, sub1);
                 let sub_no_defaults_2 = self.strip_generic_default_params(def2.did, sub2);
@@ -1138,7 +1138,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             match (terr, is_simple_error, expected == found) {
                 (&TypeError::Sorts(ref values), false, true) => {
                     let sort_string = | a_type: Ty<'tcx> |
-                        if let ty::Opaque(def_id, _) = a_type.sty {
+                        if let ty::Opaque(def_id, _) = a_type.kind {
                             format!(" (opaque type at {})", self.tcx.sess.source_map()
                                 .mk_substr_filename(self.tcx.def_span(def_id)))
                         } else {
@@ -1179,9 +1179,9 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         exp_found: &ty::error::ExpectedFound<Ty<'tcx>>,
         diag: &mut DiagnosticBuilder<'tcx>,
     ) {
-        match (&exp_found.expected.sty, &exp_found.found.sty) {
+        match (&exp_found.expected.kind, &exp_found.found.kind) {
             (ty::Adt(exp_def, exp_substs), ty::Ref(_, found_ty, _)) => {
-                if let ty::Adt(found_def, found_substs) = found_ty.sty {
+                if let ty::Adt(found_def, found_substs) = found_ty.kind {
                     let path_str = format!("{:?}", exp_def);
                     if exp_def == &found_def {
                         let opt_msg = "you can convert from `&Option<T>` to `Option<&T>` using \
@@ -1203,9 +1203,9 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                         {
                             let mut show_suggestion = true;
                             for (exp_ty, found_ty) in exp_substs.types().zip(found_substs.types()) {
-                                match exp_ty.sty {
+                                match exp_ty.kind {
                                     ty::Ref(_, exp_ty, _) => {
-                                        match (&exp_ty.sty, &found_ty.sty) {
+                                        match (&exp_ty.kind, &found_ty.kind) {
                                             (_, ty::Param(_)) |
                                             (_, ty::Infer(_)) |
                                             (ty::Param(_), _) |
diff --git a/src/librustc/infer/error_reporting/need_type_info.rs b/src/librustc/infer/error_reporting/need_type_info.rs
index 7068fe3601a62..d56a6cf1f7bcb 100644
--- a/src/librustc/infer/error_reporting/need_type_info.rs
+++ b/src/librustc/infer/error_reporting/need_type_info.rs
@@ -44,7 +44,7 @@ impl<'a, 'tcx> FindLocalByTypeVisitor<'a, 'tcx> {
             Some(ty) => {
                 let ty = self.infcx.resolve_vars_if_possible(&ty);
                 if ty.walk().any(|inner_ty| {
-                    inner_ty == self.target_ty || match (&inner_ty.sty, &self.target_ty.sty) {
+                    inner_ty == self.target_ty || match (&inner_ty.kind, &self.target_ty.kind) {
                         (&Infer(TyVar(a_vid)), &Infer(TyVar(b_vid))) => {
                             self.infcx
                                 .type_variables
@@ -151,7 +151,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         ty: Ty<'tcx>,
         highlight: Option<ty::print::RegionHighlightMode>,
     ) -> (String, Option<Span>) {
-        if let ty::Infer(ty::TyVar(ty_vid)) = ty.sty {
+        if let ty::Infer(ty::TyVar(ty_vid)) = ty.kind {
             let ty_vars = self.type_variables.borrow();
             let var_origin = ty_vars.var_origin(ty_vid);
             if let TypeVariableOriginKind::TypeParameterDefinition(name) = var_origin.kind {
@@ -219,7 +219,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         };
 
         let ty_msg = match local_visitor.found_ty {
-            Some(ty::TyS { sty: ty::Closure(def_id, substs), .. }) => {
+            Some(ty::TyS { kind: ty::Closure(def_id, substs), .. }) => {
                 let fn_sig = substs.closure_sig(*def_id, self.tcx);
                 let args = closure_args(&fn_sig);
                 let ret = fn_sig.output().skip_binder().to_string();
@@ -254,7 +254,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         );
 
         let suffix = match local_visitor.found_ty {
-            Some(ty::TyS { sty: ty::Closure(def_id, substs), .. }) => {
+            Some(ty::TyS { kind: ty::Closure(def_id, substs), .. }) => {
                 let fn_sig = substs.closure_sig(*def_id, self.tcx);
                 let ret = fn_sig.output().skip_binder().to_string();
 
diff --git a/src/librustc/infer/error_reporting/nice_region_error/util.rs b/src/librustc/infer/error_reporting/nice_region_error/util.rs
index 668c99da0034f..a2e48cf07cb7c 100644
--- a/src/librustc/infer/error_reporting/nice_region_error/util.rs
+++ b/src/librustc/infer/error_reporting/nice_region_error/util.rs
@@ -109,7 +109,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
         decl: &hir::FnDecl,
     ) -> Option<Span> {
         let ret_ty = self.tcx().type_of(scope_def_id);
-        if let ty::FnDef(_, _) = ret_ty.sty {
+        if let ty::FnDef(_, _) = ret_ty.kind {
             let sig = ret_ty.fn_sig(self.tcx());
             let late_bound_regions = self.tcx()
                 .collect_referenced_late_bound_regions(&sig.output());
diff --git a/src/librustc/infer/freshen.rs b/src/librustc/infer/freshen.rs
index 400a538baa965..9e9220cc3d8cc 100644
--- a/src/librustc/infer/freshen.rs
+++ b/src/librustc/infer/freshen.rs
@@ -153,7 +153,7 @@ impl<'a, 'tcx> TypeFolder<'tcx> for TypeFreshener<'a, 'tcx> {
 
         let tcx = self.infcx.tcx;
 
-        match t.sty {
+        match t.kind {
             ty::Infer(ty::TyVar(v)) => {
                 let opt_ty = self.infcx.type_variables.borrow_mut().probe(v).known();
                 self.freshen_ty(
diff --git a/src/librustc/infer/fudge.rs b/src/librustc/infer/fudge.rs
index 658a9c1d88805..e27766f461697 100644
--- a/src/librustc/infer/fudge.rs
+++ b/src/librustc/infer/fudge.rs
@@ -148,7 +148,7 @@ impl<'a, 'tcx> TypeFolder<'tcx> for InferenceFudger<'a, 'tcx> {
     }
 
     fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> {
-        match ty.sty {
+        match ty.kind {
             ty::Infer(ty::InferTy::TyVar(vid)) => {
                 if self.type_vars.0.contains(&vid) {
                     // This variable was created during the fudging.
diff --git a/src/librustc/infer/lattice.rs b/src/librustc/infer/lattice.rs
index 68cbef4407677..39701231aad7e 100644
--- a/src/librustc/infer/lattice.rs
+++ b/src/librustc/infer/lattice.rs
@@ -61,7 +61,7 @@ where
     let infcx = this.infcx();
     let a = infcx.type_variables.borrow_mut().replace_if_possible(a);
     let b = infcx.type_variables.borrow_mut().replace_if_possible(b);
-    match (&a.sty, &b.sty) {
+    match (&a.kind, &b.kind) {
         // If one side is known to be a variable and one is not,
         // create a variable (`v`) to represent the LUB. Make sure to
         // relate `v` to the non-type-variable first (by passing it
diff --git a/src/librustc/infer/mod.rs b/src/librustc/infer/mod.rs
index 5d556485c15f3..c1782f53f0d2f 100644
--- a/src/librustc/infer/mod.rs
+++ b/src/librustc/infer/mod.rs
@@ -614,7 +614,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
     }
 
     pub fn type_var_diverges(&'a self, ty: Ty<'_>) -> bool {
-        match ty.sty {
+        match ty.kind {
             ty::Infer(ty::TyVar(vid)) => self.type_variables.borrow().var_diverges(vid),
             _ => false,
         }
@@ -627,7 +627,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
     pub fn type_is_unconstrained_numeric(&'a self, ty: Ty<'_>) -> UnconstrainedNumeric {
         use crate::ty::error::UnconstrainedNumeric::Neither;
         use crate::ty::error::UnconstrainedNumeric::{UnconstrainedFloat, UnconstrainedInt};
-        match ty.sty {
+        match ty.kind {
             ty::Infer(ty::IntVar(vid)) => {
                 if self.int_unification_table
                     .borrow_mut()
@@ -1563,7 +1563,7 @@ impl<'a, 'tcx> ShallowResolver<'a, 'tcx> {
     }
 
     pub fn shallow_resolve(&mut self, typ: Ty<'tcx>) -> Ty<'tcx> {
-        match typ.sty {
+        match typ.kind {
             ty::Infer(ty::TyVar(v)) => {
                 // Not entirely obvious: if `typ` is a type variable,
                 // it can be resolved to an int/float variable, which
@@ -1604,7 +1604,7 @@ impl<'a, 'tcx> ShallowResolver<'a, 'tcx> {
     // are extremely hot.
     #[inline(always)]
     pub fn shallow_resolve_changed(&mut self, typ: Ty<'tcx>) -> bool {
-        match typ.sty {
+        match typ.kind {
             ty::Infer(ty::TyVar(v)) => {
                 use self::type_variable::TypeVariableValue;
 
diff --git a/src/librustc/infer/nll_relate/mod.rs b/src/librustc/infer/nll_relate/mod.rs
index 5d521def65b0b..50a2c95ed6f22 100644
--- a/src/librustc/infer/nll_relate/mod.rs
+++ b/src/librustc/infer/nll_relate/mod.rs
@@ -274,7 +274,7 @@ where
         use crate::traits::WhereClause;
         use syntax_pos::DUMMY_SP;
 
-        match value_ty.sty {
+        match value_ty.kind {
             ty::Projection(other_projection_ty) => {
                 let var = self.infcx.next_ty_var(TypeVariableOrigin {
                     kind: TypeVariableOriginKind::MiscVariable,
@@ -328,7 +328,7 @@ where
         // This only presently applies to chalk integration, as NLL
         // doesn't permit type variables to appear on both sides (and
         // doesn't use lazy norm).
-        match value_ty.sty {
+        match value_ty.kind {
             ty::Infer(ty::TyVar(value_vid)) => {
                 // Two type variables: just equate them.
                 self.infcx
@@ -548,7 +548,7 @@ where
             b = self.infcx.shallow_resolve(b);
         }
 
-        match (&a.sty, &b.sty) {
+        match (&a.kind, &b.kind) {
             (_, &ty::Infer(ty::TyVar(vid))) => {
                 if D::forbid_inference_vars() {
                     // Forbid inference variables in the RHS.
@@ -878,7 +878,7 @@ where
 
         debug!("TypeGeneralizer::tys(a={:?})", a);
 
-        match a.sty {
+        match a.kind {
             ty::Infer(ty::TyVar(_)) | ty::Infer(ty::IntVar(_)) | ty::Infer(ty::FloatVar(_))
                 if D::forbid_inference_vars() =>
             {
diff --git a/src/librustc/infer/opaque_types/mod.rs b/src/librustc/infer/opaque_types/mod.rs
index 129cfc8bcb23f..9b447f192a97a 100644
--- a/src/librustc/infer/opaque_types/mod.rs
+++ b/src/librustc/infer/opaque_types/mod.rs
@@ -720,7 +720,7 @@ where
             return false; // keep visiting
         }
 
-        match ty.sty {
+        match ty.kind {
             ty::Closure(def_id, ref substs) => {
                 // Skip lifetime parameters of the enclosing item(s)
 
@@ -857,7 +857,7 @@ impl TypeFolder<'tcx> for ReverseMapper<'tcx> {
     }
 
     fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> {
-        match ty.sty {
+        match ty.kind {
             ty::Closure(def_id, substs) => {
                 // I am a horrible monster and I pray for death. When
                 // we encounter a closure here, it is always a closure
@@ -990,7 +990,7 @@ impl<'a, 'tcx> Instantiator<'a, 'tcx> {
             ty_op: |ty| {
                 if ty.references_error() {
                     return tcx.types.err;
-                } else if let ty::Opaque(def_id, substs) = ty.sty {
+                } else if let ty::Opaque(def_id, substs) = ty.kind {
                     // Check that this is `impl Trait` type is
                     // declared by `parent_def_id` -- i.e., one whose
                     // value we are inferring.  At present, this is
diff --git a/src/librustc/infer/outlives/obligations.rs b/src/librustc/infer/outlives/obligations.rs
index e1470e4ef0232..df491aef54fb9 100644
--- a/src/librustc/infer/outlives/obligations.rs
+++ b/src/librustc/infer/outlives/obligations.rs
@@ -403,7 +403,7 @@ where
         // 'a` in the environment but `trait Foo<'b> { type Item: 'b
         // }` in the trait definition.
         approx_env_bounds.retain(|bound| {
-            match bound.0.sty {
+            match bound.0.kind {
                 ty::Projection(projection_ty) => {
                     self.verify_bound.projection_declared_bounds_from_trait(projection_ty)
                         .all(|r| r != bound.1)
diff --git a/src/librustc/infer/outlives/verify.rs b/src/librustc/infer/outlives/verify.rs
index f23e52fcfe499..3110b027c5bbe 100644
--- a/src/librustc/infer/outlives/verify.rs
+++ b/src/librustc/infer/outlives/verify.rs
@@ -44,7 +44,7 @@ impl<'cx, 'tcx> VerifyBoundCx<'cx, 'tcx> {
     }
 
     fn type_bound(&self, ty: Ty<'tcx>) -> VerifyBound<'tcx> {
-        match ty.sty {
+        match ty.kind {
             ty::Param(p) => self.param_bound(p),
             ty::Projection(data) => self.projection_bound(data),
             _ => self.recursive_type_bound(ty),
@@ -87,7 +87,7 @@ impl<'cx, 'tcx> VerifyBoundCx<'cx, 'tcx> {
         let projection_ty = GenericKind::Projection(projection_ty).to_ty(self.tcx);
         let erased_projection_ty = self.tcx.erase_regions(&projection_ty);
         self.declared_generic_bounds_from_env_with_compare_fn(|ty| {
-            if let ty::Projection(..) = ty.sty {
+            if let ty::Projection(..) = ty.kind {
                 let erased_ty = self.tcx.erase_regions(&ty);
                 erased_ty == erased_projection_ty
             } else {
diff --git a/src/librustc/infer/resolve.rs b/src/librustc/infer/resolve.rs
index 7e553d7666b22..2db18674e2f53 100644
--- a/src/librustc/infer/resolve.rs
+++ b/src/librustc/infer/resolve.rs
@@ -118,7 +118,7 @@ impl<'a, 'tcx> TypeVisitor<'tcx> for UnresolvedTypeFinder<'a, 'tcx> {
     fn visit_ty(&mut self, t: Ty<'tcx>) -> bool {
         let t = self.infcx.shallow_resolve(t);
         if t.has_infer_types() {
-            if let ty::Infer(infer_ty) = t.sty {
+            if let ty::Infer(infer_ty) = t.kind {
                 // Since we called `shallow_resolve` above, this must
                 // be an (as yet...) unresolved inference variable.
                 let ty_var_span =
@@ -188,7 +188,7 @@ impl<'a, 'tcx> TypeFolder<'tcx> for FullTypeResolver<'a, 'tcx> {
               // defaulted tuples.
         } else {
             let t = self.infcx.shallow_resolve(t);
-            match t.sty {
+            match t.kind {
                 ty::Infer(ty::TyVar(vid)) => {
                     self.err = Some(FixupError::UnresolvedTy(vid));
                     self.tcx().types.err
diff --git a/src/librustc/infer/sub.rs b/src/librustc/infer/sub.rs
index 67c97ef5d8b29..21c847e80f413 100644
--- a/src/librustc/infer/sub.rs
+++ b/src/librustc/infer/sub.rs
@@ -71,7 +71,7 @@ impl TypeRelation<'tcx> for Sub<'combine, 'infcx, 'tcx> {
         let infcx = self.fields.infcx;
         let a = infcx.type_variables.borrow_mut().replace_if_possible(a);
         let b = infcx.type_variables.borrow_mut().replace_if_possible(b);
-        match (&a.sty, &b.sty) {
+        match (&a.kind, &b.kind) {
             (&ty::Infer(TyVar(a_vid)), &ty::Infer(TyVar(b_vid))) => {
                 // Shouldn't have any LBR here, so we can safely put
                 // this under a binder below without fear of accidental
diff --git a/src/librustc/infer/type_variable.rs b/src/librustc/infer/type_variable.rs
index dd09e9a8f58a4..ce1b54bb1c81d 100644
--- a/src/librustc/infer/type_variable.rs
+++ b/src/librustc/infer/type_variable.rs
@@ -247,7 +247,7 @@ impl<'tcx> TypeVariableTable<'tcx> {
     /// instantiated, then return the with which it was
     /// instantiated. Otherwise, returns `t`.
     pub fn replace_if_possible(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
-        match t.sty {
+        match t.kind {
             ty::Infer(ty::TyVar(v)) => {
                 match self.probe(v) {
                     TypeVariableValue::Unknown { .. } => t,
diff --git a/src/librustc/lint/context.rs b/src/librustc/lint/context.rs
index f6063875ac402..e2582346de84c 100644
--- a/src/librustc/lint/context.rs
+++ b/src/librustc/lint/context.rs
@@ -829,7 +829,7 @@ impl<'a, 'tcx> LateContext<'a, 'tcx> {
                 trait_ref: Option<ty::TraitRef<'tcx>>,
             ) -> Result<Self::Path, Self::Error> {
                 if trait_ref.is_none() {
-                    if let ty::Adt(def, substs) = self_ty.sty {
+                    if let ty::Adt(def, substs) = self_ty.kind {
                         return self.print_def_path(def.did, substs);
                     }
                 }
diff --git a/src/librustc/middle/dead.rs b/src/librustc/middle/dead.rs
index 2746794e2a2c1..821ede37229b5 100644
--- a/src/librustc/middle/dead.rs
+++ b/src/librustc/middle/dead.rs
@@ -117,7 +117,7 @@ impl<'a, 'tcx> MarkSymbolVisitor<'a, 'tcx> {
     }
 
     fn handle_field_access(&mut self, lhs: &hir::Expr, hir_id: hir::HirId) {
-        match self.tables.expr_ty_adjusted(lhs).sty {
+        match self.tables.expr_ty_adjusted(lhs).kind {
             ty::Adt(def, _) => {
                 let index = self.tcx.field_index(hir_id, self.tables);
                 self.insert_def_id(def.non_enum_variant().fields[index].did);
@@ -128,7 +128,7 @@ impl<'a, 'tcx> MarkSymbolVisitor<'a, 'tcx> {
     }
 
     fn handle_field_pattern_match(&mut self, lhs: &hir::Pat, res: Res, pats: &[hir::FieldPat]) {
-        let variant = match self.tables.node_type(lhs.hir_id).sty {
+        let variant = match self.tables.node_type(lhs.hir_id).kind {
             ty::Adt(adt, _) => adt.variant_of_res(res),
             _ => span_bug!(lhs.span, "non-ADT in struct pattern")
         };
@@ -248,7 +248,7 @@ impl<'a, 'tcx> Visitor<'tcx> for MarkSymbolVisitor<'a, 'tcx> {
                 self.handle_field_access(&lhs, expr.hir_id);
             }
             hir::ExprKind::Struct(_, ref fields, _) => {
-                if let ty::Adt(ref adt, _) = self.tables.expr_ty(expr).sty {
+                if let ty::Adt(ref adt, _) = self.tables.expr_ty(expr).kind {
                     self.mark_as_used_if_union(adt, fields);
                 }
             }
diff --git a/src/librustc/middle/expr_use_visitor.rs b/src/librustc/middle/expr_use_visitor.rs
index a3110c000fb22..1b1491a8febff 100644
--- a/src/librustc/middle/expr_use_visitor.rs
+++ b/src/librustc/middle/expr_use_visitor.rs
@@ -455,7 +455,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
                 // make sure that the thing we are pointing out stays valid
                 // for the lifetime `scope_r` of the resulting ptr:
                 let expr_ty = return_if_err!(self.mc.expr_ty(expr));
-                if let ty::Ref(r, _, _) = expr_ty.sty {
+                if let ty::Ref(r, _, _) = expr_ty.kind {
                     let bk = ty::BorrowKind::from_mutbl(m);
                     self.borrow_expr(&base, r, bk, AddrOf);
                 }
@@ -553,7 +553,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
         let callee_ty = return_if_err!(self.mc.expr_ty_adjusted(callee));
         debug!("walk_callee: callee={:?} callee_ty={:?}",
                callee, callee_ty);
-        match callee_ty.sty {
+        match callee_ty.kind {
             ty::FnDef(..) | ty::FnPtr(_) => {
                 self.consume_expr(callee);
             }
@@ -658,7 +658,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
 
         // Select just those fields of the `with`
         // expression that will actually be used
-        match with_cmt.ty.sty {
+        match with_cmt.ty.kind {
             ty::Adt(adt, substs) if adt.is_struct() => {
                 // Consume those fields of the with expression that are needed.
                 for (f_index, with_field) in adt.non_enum_variant().fields.iter().enumerate() {
@@ -863,7 +863,7 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
                     // It is also a borrow or copy/move of the value being matched.
                     match bm {
                         ty::BindByReference(m) => {
-                            if let ty::Ref(r, _, _) = pat_ty.sty {
+                            if let ty::Ref(r, _, _) = pat_ty.kind {
                                 let bk = ty::BorrowKind::from_mutbl(m);
                                 delegate.borrow(pat.hir_id, pat.span, &cmt_pat, r, bk, RefBinding);
                             }
diff --git a/src/librustc/middle/intrinsicck.rs b/src/librustc/middle/intrinsicck.rs
index 1cc96c549e724..73a2e7dff6b15 100644
--- a/src/librustc/middle/intrinsicck.rs
+++ b/src/librustc/middle/intrinsicck.rs
@@ -37,7 +37,7 @@ struct ExprVisitor<'tcx> {
 /// If the type is `Option<T>`, it will return `T`, otherwise
 /// the type itself. Works on most `Option`-like types.
 fn unpack_option_like<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Ty<'tcx> {
-    let (def, substs) = match ty.sty {
+    let (def, substs) = match ty.kind {
         ty::Adt(def, substs) => (def, substs),
         _ => return ty
     };
@@ -83,7 +83,7 @@ impl ExprVisitor<'tcx> {
             // Special-case transmutting from `typeof(function)` and
             // `Option<typeof(function)>` to present a clearer error.
             let from = unpack_option_like(self.tcx.global_tcx(), from);
-            if let (&ty::FnDef(..), SizeSkeleton::Known(size_to)) = (&from.sty, sk_to) {
+            if let (&ty::FnDef(..), SizeSkeleton::Known(size_to)) = (&from.kind, sk_to) {
                 if size_to == Pointer.size(&self.tcx) {
                     struct_span_err!(self.tcx.sess, span, E0591,
                                      "can't transmute zero-sized type")
diff --git a/src/librustc/middle/mem_categorization.rs b/src/librustc/middle/mem_categorization.rs
index 73ca981bbe868..e0149a3b9de55 100644
--- a/src/librustc/middle/mem_categorization.rs
+++ b/src/librustc/middle/mem_categorization.rs
@@ -738,7 +738,7 @@ impl<'a, 'tcx> MemCategorizationContext<'a, 'tcx> {
             LocalDefId::from_def_id(closure_expr_def_id),
         );
         let ty = self.node_ty(fn_hir_id)?;
-        let kind = match ty.sty {
+        let kind = match ty.kind {
             ty::Generator(..) => ty::ClosureKind::FnOnce,
             ty::Closure(closure_def_id, closure_substs) => {
                 match self.infcx {
@@ -900,7 +900,7 @@ impl<'a, 'tcx> MemCategorizationContext<'a, 'tcx> {
         debug!("cat_rvalue_node: promotable = {:?}", promotable);
 
         // Always promote `[T; 0]` (even when e.g., borrowed mutably).
-        let promotable = match expr_ty.sty {
+        let promotable = match expr_ty.kind {
             ty::Array(_, len) if len.try_eval_usize(self.tcx, self.param_env) == Some(0) => true,
             _ => promotable,
         };
@@ -974,7 +974,7 @@ impl<'a, 'tcx> MemCategorizationContext<'a, 'tcx> {
         let place_ty = self.expr_ty(expr)?;
         let base_ty = self.expr_ty_adjusted(base)?;
 
-        let (region, mutbl) = match base_ty.sty {
+        let (region, mutbl) = match base_ty.kind {
             ty::Ref(region, _, mutbl) => (region, mutbl),
             _ => span_bug!(expr.span, "cat_overloaded_place: base is not a reference")
         };
@@ -1004,7 +1004,7 @@ impl<'a, 'tcx> MemCategorizationContext<'a, 'tcx> {
             }
         };
 
-        let ptr = match base_cmt.ty.sty {
+        let ptr = match base_cmt.ty.kind {
             ty::Adt(def, ..) if def.is_box() => Unique,
             ty::RawPtr(ref mt) => UnsafePtr(mt.mutbl),
             ty::Ref(r, _, mutbl) => {
@@ -1230,7 +1230,7 @@ impl<'a, 'tcx> MemCategorizationContext<'a, 'tcx> {
                     Res::Def(DefKind::Ctor(CtorOf::Struct, CtorKind::Fn), _)
                     | Res::SelfCtor(..) => {
                         let ty = self.pat_ty_unadjusted(&pat)?;
-                        match ty.sty {
+                        match ty.kind {
                             ty::Adt(adt_def, _) => {
                                 (cmt, adt_def.non_enum_variant().fields.len())
                             }
@@ -1303,7 +1303,7 @@ impl<'a, 'tcx> MemCategorizationContext<'a, 'tcx> {
             PatKind::Tuple(ref subpats, ddpos) => {
                 // (p1, ..., pN)
                 let ty = self.pat_ty_unadjusted(&pat)?;
-                let expected_len = match ty.sty {
+                let expected_len = match ty.kind {
                     ty::Tuple(ref tys) => tys.len(),
                     _ => span_bug!(pat.span, "tuple pattern unexpected type {:?}", ty),
                 };
diff --git a/src/librustc/mir/tcx.rs b/src/librustc/mir/tcx.rs
index d776809839743..26f718e858da8 100644
--- a/src/librustc/mir/tcx.rs
+++ b/src/librustc/mir/tcx.rs
@@ -34,7 +34,7 @@ impl<'tcx> PlaceTy<'tcx> {
     ///
     /// Note that the resulting type has not been normalized.
     pub fn field_ty(self, tcx: TyCtxt<'tcx>, f: &Field) -> Ty<'tcx> {
-        let answer = match self.ty.sty {
+        let answer = match self.ty.kind {
             ty::Adt(adt_def, substs) => {
                 let variant_def = match self.variant_index {
                     None => adt_def.non_enum_variant(),
@@ -89,7 +89,7 @@ impl<'tcx> PlaceTy<'tcx> {
             ProjectionElem::Index(_) | ProjectionElem::ConstantIndex { .. } =>
                 PlaceTy::from_ty(self.ty.builtin_index().unwrap()),
             ProjectionElem::Subslice { from, to } => {
-                PlaceTy::from_ty(match self.ty.sty {
+                PlaceTy::from_ty(match self.ty.kind {
                     ty::Array(inner, size) => {
                         let size = size.eval_usize(tcx, param_env);
                         let len = size - (from as u64) - (to as u64);
@@ -195,7 +195,7 @@ impl<'tcx> Rvalue<'tcx> {
             }
             Rvalue::Discriminant(ref place) => {
                 let ty = place.ty(local_decls, tcx).ty;
-                match ty.sty {
+                match ty.kind {
                     ty::Adt(adt_def, _) => adt_def.repr.discr_type().to_ty(tcx),
                     ty::Generator(_, substs, _) => substs.discr_ty(tcx),
                     _ => {
diff --git a/src/librustc/query/mod.rs b/src/librustc/query/mod.rs
index 6cd1be460d7c6..38af38b828238 100644
--- a/src/librustc/query/mod.rs
+++ b/src/librustc/query/mod.rs
@@ -290,7 +290,7 @@ rustc_queries! {
         query associated_item(_: DefId) -> ty::AssocItem {}
 
         query impl_trait_ref(_: DefId) -> Option<ty::TraitRef<'tcx>> {}
-        query impl_polarity(_: DefId) -> hir::ImplPolarity {}
+        query impl_polarity(_: DefId) -> ty::ImplPolarity {}
 
         query issue33140_self_ty(_: DefId) -> Option<ty::Ty<'tcx>> {}
     }
diff --git a/src/librustc/traits/auto_trait.rs b/src/librustc/traits/auto_trait.rs
index d89cf8eb3e843..9faf58aee6f92 100644
--- a/src/librustc/traits/auto_trait.rs
+++ b/src/librustc/traits/auto_trait.rs
@@ -321,7 +321,7 @@ impl AutoTraitFinder<'tcx> {
                     match vtable {
                         Vtable::VtableImpl(VtableImplData { impl_def_id, .. }) => {
                             // Blame tidy for the weird bracket placement
-                            if infcx.tcx.impl_polarity(*impl_def_id) == hir::ImplPolarity::Negative
+                            if infcx.tcx.impl_polarity(*impl_def_id) == ty::ImplPolarity::Negative
                             {
                                 debug!("evaluate_nested_obligations: Found explicit negative impl\
                                         {:?}, bailing out", impl_def_id);
@@ -601,7 +601,7 @@ impl AutoTraitFinder<'tcx> {
     }
 
     pub fn is_of_param(&self, ty: Ty<'_>) -> bool {
-        return match ty.sty {
+        return match ty.kind {
             ty::Param(_) => true,
             ty::Projection(p) => self.is_of_param(p.self_ty()),
             _ => false,
@@ -609,7 +609,7 @@ impl AutoTraitFinder<'tcx> {
     }
 
     fn is_self_referential_projection(&self, p: ty::PolyProjectionPredicate<'_>) -> bool {
-        match p.ty().skip_binder().sty {
+        match p.ty().skip_binder().kind {
             ty::Projection(proj) if proj == p.skip_binder().projection_ty => {
                 true
             },
diff --git a/src/librustc/traits/coherence.rs b/src/librustc/traits/coherence.rs
index ee318b127ae66..039973d80dbf1 100644
--- a/src/librustc/traits/coherence.rs
+++ b/src/librustc/traits/coherence.rs
@@ -383,7 +383,7 @@ fn orphan_check_trait_ref<'tcx>(
             if ty_is_local(tcx, input_ty, in_crate) {
                 debug!("orphan_check_trait_ref: ty_is_local `{:?}`", input_ty);
                 return Ok(());
-            } else if let ty::Param(_) = input_ty.sty {
+            } else if let ty::Param(_) = input_ty.kind {
                 debug!("orphan_check_trait_ref: uncovered ty: `{:?}`", input_ty);
                 return Err(OrphanCheckErr::UncoveredTy(input_ty))
             }
@@ -444,7 +444,7 @@ fn uncovered_tys<'tcx>(tcx: TyCtxt<'_>, ty: Ty<'tcx>, in_crate: InCrate) -> Vec<
 }
 
 fn is_possibly_remote_type(ty: Ty<'_>, _in_crate: InCrate) -> bool {
-    match ty.sty {
+    match ty.kind {
         ty::Projection(..) | ty::Param(..) => true,
         _ => false,
     }
@@ -456,7 +456,7 @@ fn ty_is_local(tcx: TyCtxt<'_>, ty: Ty<'_>, in_crate: InCrate) -> bool {
 }
 
 fn fundamental_ty(ty: Ty<'_>) -> bool {
-    match ty.sty {
+    match ty.kind {
         ty::Ref(..) => true,
         ty::Adt(def, _) => def.is_fundamental(),
         _ => false
@@ -475,7 +475,7 @@ fn def_id_is_local(def_id: DefId, in_crate: InCrate) -> bool {
 fn ty_is_local_constructor(tcx: TyCtxt<'_>, ty: Ty<'_>, in_crate: InCrate) -> bool {
     debug!("ty_is_local_constructor({:?})", ty);
 
-    match ty.sty {
+    match ty.kind {
         ty::Bool |
         ty::Char |
         ty::Int(..) |
diff --git a/src/librustc/traits/error_reporting.rs b/src/librustc/traits/error_reporting.rs
index 08fea75739978..0683940af985e 100644
--- a/src/librustc/traits/error_reporting.rs
+++ b/src/librustc/traits/error_reporting.rs
@@ -258,7 +258,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         /// returns the fuzzy category of a given type, or None
         /// if the type can be equated to any type.
         fn type_category(t: Ty<'_>) -> Option<u32> {
-            match t.sty {
+            match t.kind {
                 ty::Bool => Some(0),
                 ty::Char => Some(1),
                 ty::Str => Some(2),
@@ -288,7 +288,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         }
 
         match (type_category(a), type_category(b)) {
-            (Some(cat_a), Some(cat_b)) => match (&a.sty, &b.sty) {
+            (Some(cat_a), Some(cat_b)) => match (&a.kind, &b.kind) {
                 (&ty::Adt(def_a, _), &ty::Adt(def_b, _)) => def_a == def_b,
                 _ => cat_a == cat_b
             },
@@ -419,7 +419,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             flags.push((sym::_Self, Some("{integral}".to_owned())));
         }
 
-        if let ty::Array(aty, len) = self_ty.sty {
+        if let ty::Array(aty, len) = self_ty.kind {
             flags.push((sym::_Self, Some("[]".to_owned())));
             flags.push((sym::_Self, Some(format!("[{}]", aty))));
             if let Some(def) = aty.ty_adt_def() {
@@ -876,7 +876,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
 
                 let found_trait_ty = found_trait_ref.self_ty();
 
-                let found_did = match found_trait_ty.sty {
+                let found_did = match found_trait_ty.kind {
                     ty::Closure(did, _) | ty::Foreign(did) | ty::FnDef(did, _) => Some(did),
                     ty::Adt(def, _) => Some(def.did),
                     _ => None,
@@ -886,13 +886,13 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
                     self.tcx.hir().span_if_local(did)
                 ).map(|sp| self.tcx.sess.source_map().def_span(sp)); // the sp could be an fn def
 
-                let found = match found_trait_ref.skip_binder().substs.type_at(1).sty {
+                let found = match found_trait_ref.skip_binder().substs.type_at(1).kind {
                     ty::Tuple(ref tys) => vec![ArgKind::empty(); tys.len()],
                     _ => vec![ArgKind::empty()],
                 };
 
                 let expected_ty = expected_trait_ref.skip_binder().substs.type_at(1);
-                let expected = match expected_ty.sty {
+                let expected = match expected_ty.kind {
                     ty::Tuple(ref tys) => tys.iter()
                         .map(|t| ArgKind::from_expected_ty(t.expect_ty(), Some(span))).collect(),
                     _ => vec![ArgKind::Arg("_".to_owned(), expected_ty.to_string())],
@@ -979,7 +979,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
         points_at_arg: bool,
     ) {
         let self_ty = trait_ref.self_ty();
-        match self_ty.sty {
+        match self_ty.kind {
             ty::FnDef(def_id, _) => {
                 // We tried to apply the bound to an `fn`. Check whether calling it would evaluate
                 // to a type that *would* satisfy the trait binding. If it would, suggest calling
@@ -1066,7 +1066,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             let mut trait_type = trait_ref.self_ty();
 
             for refs_remaining in 0..refs_number {
-                if let ty::Ref(_, t_type, _) = trait_type.sty {
+                if let ty::Ref(_, t_type, _) = trait_type.kind {
                     trait_type = t_type;
 
                     let substs = self.tcx.mk_substs_trait(trait_type, &[]);
@@ -1340,7 +1340,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
     ) -> DiagnosticBuilder<'tcx> {
         fn build_fn_sig_string<'tcx>(tcx: TyCtxt<'tcx>, trait_ref: &ty::TraitRef<'tcx>) -> String {
             let inputs = trait_ref.substs.type_at(1);
-            let sig = if let ty::Tuple(inputs) = inputs.sty {
+            let sig = if let ty::Tuple(inputs) = inputs.kind {
                 tcx.mk_fn_sig(
                     inputs.iter().map(|k| k.expect_ty()),
                     tcx.mk_ty_infer(ty::TyVar(ty::TyVid { index: 0 })),
@@ -1463,7 +1463,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             ty::Predicate::Trait(ref data) => {
                 let trait_ref = data.to_poly_trait_ref();
                 let self_ty = trait_ref.self_ty();
-                debug!("self_ty {:?} {:?} trait_ref {:?}", self_ty, self_ty.sty, trait_ref);
+                debug!("self_ty {:?} {:?} trait_ref {:?}", self_ty, self_ty.kind, trait_ref);
 
                 if predicate.references_error() {
                     return;
@@ -1564,7 +1564,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             fn tcx<'b>(&'b self) -> TyCtxt<'tcx> { self.infcx.tcx }
 
             fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> {
-                if let ty::Param(ty::ParamTy {name, .. }) = ty.sty {
+                if let ty::Param(ty::ParamTy {name, .. }) = ty.kind {
                     let infcx = self.infcx;
                     self.var_map.entry(ty).or_insert_with(||
                         infcx.next_ty_var(
@@ -1834,7 +1834,7 @@ impl ArgKind {
     /// Creates an `ArgKind` from the expected type of an
     /// argument. It has no name (`_`) and an optional source span.
     pub fn from_expected_ty(t: Ty<'_>, span: Option<Span>) -> ArgKind {
-        match t.sty {
+        match t.kind {
             ty::Tuple(ref tys) => ArgKind::Tuple(
                 span,
                 tys.iter()
diff --git a/src/librustc/traits/fulfill.rs b/src/librustc/traits/fulfill.rs
index 6c421e9df6800..0a190af1f986d 100644
--- a/src/librustc/traits/fulfill.rs
+++ b/src/librustc/traits/fulfill.rs
@@ -548,7 +548,7 @@ fn trait_ref_type_vars<'a, 'tcx>(
      .map(|t| selcx.infcx().resolve_vars_if_possible(&t))
      .filter(|t| t.has_infer_types())
      .flat_map(|t| t.walk())
-     .filter(|t| match t.sty { ty::Infer(_) => true, _ => false })
+     .filter(|t| match t.kind { ty::Infer(_) => true, _ => false })
      .collect()
 }
 
diff --git a/src/librustc/traits/object_safety.rs b/src/librustc/traits/object_safety.rs
index a7990c4af69fd..e0ef179911b6c 100644
--- a/src/librustc/traits/object_safety.rs
+++ b/src/librustc/traits/object_safety.rs
@@ -677,7 +677,7 @@ impl<'tcx> TyCtxt<'tcx> {
         let mut error = false;
         let self_ty = self.types.self_param;
         ty.maybe_walk(|ty| {
-            match ty.sty {
+            match ty.kind {
                 ty::Param(_) => {
                     if ty == self_ty {
                         error = true;
diff --git a/src/librustc/traits/project.rs b/src/librustc/traits/project.rs
index 87a23f655a8f3..57077bcdffa72 100644
--- a/src/librustc/traits/project.rs
+++ b/src/librustc/traits/project.rs
@@ -337,7 +337,7 @@ impl<'a, 'b, 'tcx> TypeFolder<'tcx> for AssocTypeNormalizer<'a, 'b, 'tcx> {
         // should occur eventually).
 
         let ty = ty.super_fold_with(self);
-        match ty.sty {
+        match ty.kind {
             ty::Opaque(def_id, substs) if !substs.has_escaping_bound_vars() => { // (*)
                 // Only normalize `impl Trait` after type-checking, usually in codegen.
                 match self.param_env.reveal {
@@ -921,7 +921,7 @@ fn assemble_candidates_from_trait_def<'cx, 'tcx>(
 
     let tcx = selcx.tcx();
     // Check whether the self-type is itself a projection.
-    let (def_id, substs) = match obligation_trait_ref.self_ty().sty {
+    let (def_id, substs) = match obligation_trait_ref.self_ty().kind {
         ty::Projection(ref data) => {
             (data.trait_ref(tcx).def_id, data.substs)
         }
@@ -1199,7 +1199,7 @@ fn confirm_object_candidate<'cx, 'tcx>(
     let object_ty = selcx.infcx().shallow_resolve(self_ty);
     debug!("confirm_object_candidate(object_ty={:?})",
            object_ty);
-    let data = match object_ty.sty {
+    let data = match object_ty.kind {
         ty::Dynamic(ref data, ..) => data,
         _ => {
             span_bug!(
diff --git a/src/librustc/traits/query/dropck_outlives.rs b/src/librustc/traits/query/dropck_outlives.rs
index 46403a38c99bd..673cae1ca0309 100644
--- a/src/librustc/traits/query/dropck_outlives.rs
+++ b/src/librustc/traits/query/dropck_outlives.rs
@@ -186,7 +186,7 @@ impl_stable_hash_for!(struct DtorckConstraint<'tcx> {
 /// Note also that `needs_drop` requires a "global" type (i.e., one
 /// with erased regions), but this function does not.
 pub fn trivial_dropck_outlives<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> bool {
-    match ty.sty {
+    match ty.kind {
         // None of these types have a destructor and hence they do not
         // require anything in particular to outlive the dtor's
         // execution.
diff --git a/src/librustc/traits/query/normalize.rs b/src/librustc/traits/query/normalize.rs
index c31ff3ab1b55d..b334e6dd8f84e 100644
--- a/src/librustc/traits/query/normalize.rs
+++ b/src/librustc/traits/query/normalize.rs
@@ -88,7 +88,7 @@ impl<'cx, 'tcx> TypeFolder<'tcx> for QueryNormalizer<'cx, 'tcx> {
 
     fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> {
         let ty = ty.super_fold_with(self);
-        match ty.sty {
+        match ty.kind {
             ty::Opaque(def_id, substs) if !substs.has_escaping_bound_vars() => {
                 // (*)
                 // Only normalize `impl Trait` after type-checking, usually in codegen.
diff --git a/src/librustc/traits/select.rs b/src/librustc/traits/select.rs
index 386a5677f5f17..911ecef802425 100644
--- a/src/librustc/traits/select.rs
+++ b/src/librustc/traits/select.rs
@@ -43,6 +43,8 @@ use crate::hir;
 use rustc_data_structures::bit_set::GrowableBitSet;
 use rustc_data_structures::sync::Lock;
 use rustc_target::spec::abi::Abi;
+use syntax::attr;
+use syntax::symbol::sym;
 use std::cell::{Cell, RefCell};
 use std::cmp;
 use std::fmt::{self, Display};
@@ -99,6 +101,9 @@ pub enum IntercrateAmbiguityCause {
         trait_desc: String,
         self_desc: Option<String>,
     },
+    ReservationImpl {
+        message: String
+    },
 }
 
 impl IntercrateAmbiguityCause {
@@ -139,6 +144,11 @@ impl IntercrateAmbiguityCause {
                     trait_desc, self_desc
                 )
             }
+            &IntercrateAmbiguityCause::ReservationImpl {
+                ref message
+            } => {
+                message.clone()
+            }
         }
     }
 }
@@ -1326,17 +1336,38 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         (result, dep_node)
     }
 
-    // Treat negative impls as unimplemented
-    fn filter_negative_impls(
-        &self,
+    // Treat negative impls as unimplemented, and reservation impls as ambiguity.
+    fn filter_negative_and_reservation_impls(
+        &mut self,
         candidate: SelectionCandidate<'tcx>,
     ) -> SelectionResult<'tcx, SelectionCandidate<'tcx>> {
         if let ImplCandidate(def_id) = candidate {
-            if !self.allow_negative_impls
-                && self.tcx().impl_polarity(def_id) == hir::ImplPolarity::Negative
-            {
-                return Err(Unimplemented);
-            }
+            let tcx = self.tcx();
+            match tcx.impl_polarity(def_id) {
+                ty::ImplPolarity::Negative if !self.allow_negative_impls => {
+                    return Err(Unimplemented);
+                }
+                ty::ImplPolarity::Reservation => {
+                    if let Some(intercrate_ambiguity_clauses)
+                        = &mut self.intercrate_ambiguity_causes
+                    {
+                        let attrs = tcx.get_attrs(def_id);
+                        let attr = attr::find_by_name(&attrs, sym::rustc_reservation_impl);
+                        let value = attr.and_then(|a| a.value_str());
+                        if let Some(value) = value {
+                            debug!("filter_negative_and_reservation_impls: \
+                                    reservation impl ambiguity on {:?}", def_id);
+                            intercrate_ambiguity_clauses.push(
+                                IntercrateAmbiguityCause::ReservationImpl {
+                                    message: value.to_string()
+                                }
+                            );
+                        }
+                    }
+                    return Ok(None);
+                }
+                _ => {}
+            };
         }
         Ok(Some(candidate))
     }
@@ -1453,7 +1484,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         // Instead, we select the right impl now but report `Bar does
         // not implement Clone`.
         if candidates.len() == 1 {
-            return self.filter_negative_impls(candidates.pop().unwrap());
+            return self.filter_negative_and_reservation_impls(candidates.pop().unwrap());
         }
 
         // Winnow, but record the exact outcome of evaluation, which
@@ -1528,7 +1559,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         }
 
         // Just one candidate left.
-        self.filter_negative_impls(candidates.pop().unwrap().candidate)
+        self.filter_negative_and_reservation_impls(candidates.pop().unwrap().candidate)
     }
 
     fn is_knowable<'o>(&mut self, stack: &TraitObligationStack<'o, 'tcx>) -> Option<Conflict> {
@@ -1785,7 +1816,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
         // before we go into the whole placeholder thing, just
         // quickly check if the self-type is a projection at all.
-        match obligation.predicate.skip_binder().trait_ref.self_ty().sty {
+        match obligation.predicate.skip_binder().trait_ref.self_ty().kind {
             ty::Projection(_) | ty::Opaque(..) => {}
             ty::Infer(ty::TyVar(_)) => {
                 span_bug!(
@@ -1823,7 +1854,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             placeholder_trait_predicate,
         );
 
-        let (def_id, substs) = match placeholder_trait_predicate.trait_ref.self_ty().sty {
+        let (def_id, substs) = match placeholder_trait_predicate.trait_ref.self_ty().kind {
             ty::Projection(ref data) => (data.trait_ref(self.tcx()).def_id, data.substs),
             ty::Opaque(def_id, substs) => (def_id, substs),
             _ => {
@@ -1971,7 +2002,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         // touch bound regions, they just capture the in-scope
         // type/region parameters.
         let self_ty = *obligation.self_ty().skip_binder();
-        match self_ty.sty {
+        match self_ty.kind {
             ty::Generator(..) => {
                 debug!(
                     "assemble_generator_candidates: self_ty={:?} obligation={:?}",
@@ -2014,7 +2045,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         // Okay to skip binder because the substs on closure types never
         // touch bound regions, they just capture the in-scope
         // type/region parameters
-        match obligation.self_ty().skip_binder().sty {
+        match obligation.self_ty().skip_binder().kind {
             ty::Closure(closure_def_id, closure_substs) => {
                 debug!(
                     "assemble_unboxed_candidates: kind={:?} obligation={:?}",
@@ -2063,7 +2094,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
         // Okay to skip binder because what we are inspecting doesn't involve bound regions
         let self_ty = *obligation.self_ty().skip_binder();
-        match self_ty.sty {
+        match self_ty.kind {
             ty::Infer(ty::TyVar(_)) => {
                 debug!("assemble_fn_pointer_candidates: ambiguous self-type");
                 candidates.ambiguous = true; // could wind up being a fn() type
@@ -2125,7 +2156,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         let def_id = obligation.predicate.def_id();
 
         if self.tcx().trait_is_auto(def_id) {
-            match self_ty.sty {
+            match self_ty.kind {
                 ty::Dynamic(..) => {
                     // For object types, we don't know what the closed
                     // over types are. This means we conservatively
@@ -2198,7 +2229,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             // self-ty here doesn't escape this probe, so just erase
             // any LBR.
             let self_ty = self.tcx().erase_late_bound_regions(&obligation.self_ty());
-            let poly_trait_ref = match self_ty.sty {
+            let poly_trait_ref = match self_ty.kind {
                 ty::Dynamic(ref data, ..) => {
                     if data.auto_traits()
                         .any(|did| did == obligation.predicate.def_id())
@@ -2294,7 +2325,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             source, target
         );
 
-        let may_apply = match (&source.sty, &target.sty) {
+        let may_apply = match (&source.kind, &target.kind) {
             // Trait+Kx+'a -> Trait+Ky+'b (upcasts).
             (&ty::Dynamic(ref data_a, ..), &ty::Dynamic(ref data_b, ..)) => {
                 // Upcasts permit two things:
@@ -2532,7 +2563,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         let self_ty = self.infcx
             .shallow_resolve(obligation.predicate.skip_binder().self_ty());
 
-        match self_ty.sty {
+        match self_ty.kind {
             ty::Infer(ty::IntVar(_))
             | ty::Infer(ty::FloatVar(_))
             | ty::Uint(_)
@@ -2598,7 +2629,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
 
         use self::BuiltinImplConditions::{Ambiguous, None, Where};
 
-        match self_ty.sty {
+        match self_ty.kind {
             ty::Infer(ty::IntVar(_))
             | ty::Infer(ty::FloatVar(_))
             | ty::FnDef(..)
@@ -2680,7 +2711,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
     /// Zed<i32> where enum Zed { A(T), B(u32) } -> [i32, u32]
     /// ```
     fn constituent_types_for_ty(&self, t: Ty<'tcx>) -> Vec<Ty<'tcx>> {
-        match t.sty {
+        match t.kind {
             ty::Uint(_)
             | ty::Int(_)
             | ty::Bool
@@ -3118,7 +3149,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         // results.
         let self_ty = self.infcx
             .shallow_resolve(*obligation.self_ty().skip_binder());
-        let poly_trait_ref = match self_ty.sty {
+        let poly_trait_ref = match self_ty.kind {
             ty::Dynamic(ref data, ..) =>
                 data.principal().unwrap_or_else(|| {
                     span_bug!(obligation.cause.span, "object candidate with no principal")
@@ -3252,7 +3283,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         // touch bound regions, they just capture the in-scope
         // type/region parameters.
         let self_ty = self.infcx.shallow_resolve(*obligation.self_ty().skip_binder());
-        let (generator_def_id, substs) = match self_ty.sty {
+        let (generator_def_id, substs) = match self_ty.kind {
             ty::Generator(id, substs, _) => (id, substs),
             _ => bug!("closure candidate for non-closure {:?}", obligation),
         };
@@ -3309,7 +3340,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         // touch bound regions, they just capture the in-scope
         // type/region parameters.
         let self_ty = self.infcx.shallow_resolve(*obligation.self_ty().skip_binder());
-        let (closure_def_id, substs) = match self_ty.sty {
+        let (closure_def_id, substs) = match self_ty.kind {
             ty::Closure(id, substs) => (id, substs),
             _ => bug!("closure candidate for non-closure {:?}", obligation),
         };
@@ -3418,7 +3449,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
         );
 
         let mut nested = vec![];
-        match (&source.sty, &target.sty) {
+        match (&source.kind, &target.kind) {
             // Trait+Kx+'a -> Trait+Ky+'b (upcasts).
             (&ty::Dynamic(ref data_a, r_a), &ty::Dynamic(ref data_b, r_b)) => {
                 // See assemble_candidates_for_unsizing for more info.
@@ -3550,7 +3581,7 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
                 let mut ty_params = GrowableBitSet::new_empty();
                 let mut found = false;
                 for ty in field.walk() {
-                    if let ty::Param(p) = ty.sty {
+                    if let ty::Param(p) = ty.kind {
                         ty_params.insert(p.index as usize);
                         found = true;
                     }
@@ -3728,6 +3759,13 @@ impl<'cx, 'tcx> SelectionContext<'cx, 'tcx> {
             return Err(());
         }
 
+        if self.intercrate.is_none()
+            && self.tcx().impl_polarity(impl_def_id) == ty::ImplPolarity::Reservation
+        {
+            debug!("match_impl: reservation impls only apply in intercrate mode");
+            return Err(());
+        }
+
         debug!("match_impl: success impl_substs={:?}", impl_substs);
         Ok(Normalized {
             value: impl_substs,
diff --git a/src/librustc/traits/specialize/specialization_graph.rs b/src/librustc/traits/specialize/specialization_graph.rs
index c9a40db41dfde..8cbadebaea5a5 100644
--- a/src/librustc/traits/specialize/specialization_graph.rs
+++ b/src/librustc/traits/specialize/specialization_graph.rs
@@ -85,11 +85,11 @@ impl<'tcx> Children {
     /// Insert an impl into this set of children without comparing to any existing impls.
     fn insert_blindly(&mut self, tcx: TyCtxt<'tcx>, impl_def_id: DefId) {
         let trait_ref = tcx.impl_trait_ref(impl_def_id).unwrap();
-        if let Some(sty) = fast_reject::simplify_type(tcx, trait_ref.self_ty(), false) {
-            debug!("insert_blindly: impl_def_id={:?} sty={:?}", impl_def_id, sty);
-            self.nonblanket_impls.entry(sty).or_default().push(impl_def_id)
+        if let Some(st) = fast_reject::simplify_type(tcx, trait_ref.self_ty(), false) {
+            debug!("insert_blindly: impl_def_id={:?} st={:?}", impl_def_id, st);
+            self.nonblanket_impls.entry(st).or_default().push(impl_def_id)
         } else {
-            debug!("insert_blindly: impl_def_id={:?} sty=None", impl_def_id);
+            debug!("insert_blindly: impl_def_id={:?} st=None", impl_def_id);
             self.blanket_impls.push(impl_def_id)
         }
     }
@@ -100,11 +100,11 @@ impl<'tcx> Children {
     fn remove_existing(&mut self, tcx: TyCtxt<'tcx>, impl_def_id: DefId) {
         let trait_ref = tcx.impl_trait_ref(impl_def_id).unwrap();
         let vec: &mut Vec<DefId>;
-        if let Some(sty) = fast_reject::simplify_type(tcx, trait_ref.self_ty(), false) {
-            debug!("remove_existing: impl_def_id={:?} sty={:?}", impl_def_id, sty);
-            vec = self.nonblanket_impls.get_mut(&sty).unwrap();
+        if let Some(st) = fast_reject::simplify_type(tcx, trait_ref.self_ty(), false) {
+            debug!("remove_existing: impl_def_id={:?} st={:?}", impl_def_id, st);
+            vec = self.nonblanket_impls.get_mut(&st).unwrap();
         } else {
-            debug!("remove_existing: impl_def_id={:?} sty=None", impl_def_id);
+            debug!("remove_existing: impl_def_id={:?} st=None", impl_def_id);
             vec = &mut self.blanket_impls;
         }
 
@@ -130,7 +130,7 @@ impl<'tcx> Children {
         );
 
         let possible_siblings = match simplified_self {
-            Some(sty) => PotentialSiblings::Filtered(self.filtered(sty)),
+            Some(st) => PotentialSiblings::Filtered(self.filtered(st)),
             None => PotentialSiblings::Unfiltered(self.iter()),
         };
 
@@ -249,8 +249,8 @@ impl<'tcx> Children {
         self.blanket_impls.iter().chain(nonblanket).cloned()
     }
 
-    fn filtered(&mut self, sty: SimplifiedType) -> impl Iterator<Item = DefId> + '_ {
-        let nonblanket = self.nonblanket_impls.entry(sty).or_default().iter();
+    fn filtered(&mut self, st: SimplifiedType) -> impl Iterator<Item = DefId> + '_ {
+        let nonblanket = self.nonblanket_impls.entry(st).or_default().iter();
         self.blanket_impls.iter().chain(nonblanket).cloned()
     }
 }
diff --git a/src/librustc/traits/structural_impls.rs b/src/librustc/traits/structural_impls.rs
index c0d8230999dd8..dab62a6bcb5b1 100644
--- a/src/librustc/traits/structural_impls.rs
+++ b/src/librustc/traits/structural_impls.rs
@@ -312,7 +312,7 @@ impl<'tcx> TypeVisitor<'tcx> for BoundNamesCollector {
     }
 
     fn visit_ty(&mut self, t: Ty<'tcx>) -> bool {
-        match t.sty {
+        match t.kind {
             ty::Bound(debruijn, bound_ty) if debruijn == self.binder_index => {
                 self.types.insert(
                     bound_ty.var.as_u32(),
diff --git a/src/librustc/ty/_match.rs b/src/librustc/ty/_match.rs
index f800a70e0becf..a0d22789dae35 100644
--- a/src/librustc/ty/_match.rs
+++ b/src/librustc/ty/_match.rs
@@ -59,7 +59,7 @@ impl TypeRelation<'tcx> for Match<'tcx> {
                a, b);
         if a == b { return Ok(a); }
 
-        match (&a.sty, &b.sty) {
+        match (&a.kind, &b.kind) {
             (_, &ty::Infer(ty::FreshTy(_))) |
             (_, &ty::Infer(ty::FreshIntTy(_))) |
             (_, &ty::Infer(ty::FreshFloatTy(_))) => {
diff --git a/src/librustc/ty/cast.rs b/src/librustc/ty/cast.rs
index 7ea5c73c5b749..bc12412312deb 100644
--- a/src/librustc/ty/cast.rs
+++ b/src/librustc/ty/cast.rs
@@ -52,7 +52,7 @@ impl<'tcx> CastTy<'tcx> {
     /// Returns `Some` for integral/pointer casts.
     /// casts like unsizing casts will return `None`
     pub fn from_ty(t: Ty<'tcx>) -> Option<CastTy<'tcx>> {
-        match t.sty {
+        match t.kind {
             ty::Bool => Some(CastTy::Int(IntTy::Bool)),
             ty::Char => Some(CastTy::Int(IntTy::Char)),
             ty::Int(_) => Some(CastTy::Int(IntTy::I)),
diff --git a/src/librustc/ty/codec.rs b/src/librustc/ty/codec.rs
index 1aa21501129c8..bd4913c88fd1f 100644
--- a/src/librustc/ty/codec.rs
+++ b/src/librustc/ty/codec.rs
@@ -31,7 +31,7 @@ pub trait EncodableWithShorthand: Clone + Eq + Hash {
 impl<'tcx> EncodableWithShorthand for Ty<'tcx> {
     type Variant = ty::TyKind<'tcx>;
     fn variant(&self) -> &Self::Variant {
-        &self.sty
+        &self.kind
     }
 }
 
diff --git a/src/librustc/ty/context.rs b/src/librustc/ty/context.rs
index a25ef21d6978f..8a466567319e7 100644
--- a/src/librustc/ty/context.rs
+++ b/src/librustc/ty/context.rs
@@ -138,7 +138,7 @@ impl<'tcx> CtxtInterners<'tcx> {
             let flags = super::flags::FlagComputation::for_sty(&st);
 
             let ty_struct = TyS {
-                sty: st,
+                kind: st,
                 flags: flags.flags,
                 outer_exclusive_binder: flags.outer_exclusive_binder,
             };
@@ -828,7 +828,7 @@ impl CanonicalUserType<'tcx> {
 
                 user_substs.substs.iter().zip(BoundVar::new(0)..).all(|(kind, cvar)| {
                     match kind.unpack() {
-                        UnpackedKind::Type(ty) => match ty.sty {
+                        UnpackedKind::Type(ty) => match ty.kind {
                             ty::Bound(debruijn, b) => {
                                 // We only allow a `ty::INNERMOST` index in substitutions.
                                 assert_eq!(debruijn, ty::INNERMOST);
@@ -890,7 +890,7 @@ EnumLiftImpl! {
 
 impl<'tcx> CommonTypes<'tcx> {
     fn new(interners: &CtxtInterners<'tcx>) -> CommonTypes<'tcx> {
-        let mk = |sty| interners.intern_ty(sty);
+        let mk = |ty| interners.intern_ty(ty);
 
         CommonTypes {
             unit: mk(Tuple(List::empty())),
@@ -1565,7 +1565,7 @@ impl<'tcx> TyCtxt<'tcx> {
         }
 
         let ret_ty = self.type_of(scope_def_id);
-        match ret_ty.sty {
+        match ret_ty.kind {
             ty::FnDef(_, _) => {
                 let sig = ret_ty.fn_sig(*self);
                 let output = self.erase_late_bound_regions(&sig.output());
@@ -2011,7 +2011,7 @@ macro_rules! sty_debug_print {
                 let shards = tcx.interners.type_.lock_shards();
                 let types = shards.iter().flat_map(|shard| shard.keys());
                 for &Interned(t) in types {
-                    let variant = match t.sty {
+                    let variant = match t.kind {
                         ty::Bool | ty::Char | ty::Int(..) | ty::Uint(..) |
                             ty::Float(..) | ty::Str | ty::Never => continue,
                         ty::Error => /* unimportant */ continue,
@@ -2080,10 +2080,10 @@ impl<'tcx, T: 'tcx+?Sized> Clone for Interned<'tcx, T> {
 }
 impl<'tcx, T: 'tcx+?Sized> Copy for Interned<'tcx, T> {}
 
-// N.B., an `Interned<Ty>` compares and hashes as a sty.
+// N.B., an `Interned<Ty>` compares and hashes as a `TyKind`.
 impl<'tcx> PartialEq for Interned<'tcx, TyS<'tcx>> {
     fn eq(&self, other: &Interned<'tcx, TyS<'tcx>>) -> bool {
-        self.0.sty == other.0.sty
+        self.0.kind == other.0.kind
     }
 }
 
@@ -2091,14 +2091,14 @@ impl<'tcx> Eq for Interned<'tcx, TyS<'tcx>> {}
 
 impl<'tcx> Hash for Interned<'tcx, TyS<'tcx>> {
     fn hash<H: Hasher>(&self, s: &mut H) {
-        self.0.sty.hash(s)
+        self.0.kind.hash(s)
     }
 }
 
 #[allow(rustc::usage_of_ty_tykind)]
 impl<'tcx> Borrow<TyKind<'tcx>> for Interned<'tcx, TyS<'tcx>> {
     fn borrow<'a>(&'a self) -> &'a TyKind<'tcx> {
-        &self.0.sty
+        &self.0.kind
     }
 }
 
@@ -2292,7 +2292,7 @@ impl<'tcx> TyCtxt<'tcx> {
     /// It cannot convert a closure that requires unsafe.
     pub fn coerce_closure_fn_ty(self, sig: PolyFnSig<'tcx>, unsafety: hir::Unsafety) -> Ty<'tcx> {
         let converted_sig = sig.map_bound(|s| {
-            let params_iter = match s.inputs()[0].sty {
+            let params_iter = match s.inputs()[0].kind {
                 ty::Tuple(params) => {
                     params.into_iter().map(|k| k.expect_ty())
                 }
diff --git a/src/librustc/ty/error.rs b/src/librustc/ty/error.rs
index 125c48f5f31d7..d12039de3136e 100644
--- a/src/librustc/ty/error.rs
+++ b/src/librustc/ty/error.rs
@@ -185,7 +185,7 @@ impl<'tcx> fmt::Display for TypeError<'tcx> {
 
 impl<'tcx> ty::TyS<'tcx> {
     pub fn sort_string(&self, tcx: TyCtxt<'_>) -> Cow<'static, str> {
-        match self.sty {
+        match self.kind {
             ty::Bool | ty::Char | ty::Int(_) |
             ty::Uint(_) | ty::Float(_) | ty::Str | ty::Never => self.to_string().into(),
             ty::Tuple(ref tys) if tys.is_empty() => self.to_string().into(),
@@ -275,7 +275,7 @@ impl<'tcx> TyCtxt<'tcx> {
                                  `.await`ing on both of them");
                     }
                 }
-                match (&values.expected.sty, &values.found.sty) {
+                match (&values.expected.kind, &values.found.kind) {
                     (ty::Float(_), ty::Infer(ty::IntVar(_))) => if let Ok( // Issue #53280
                         snippet,
                     ) = self.sess.source_map().span_to_snippet(sp) {
@@ -373,9 +373,9 @@ impl Trait for X {
                 debug!(
                     "note_and_explain_type_err expected={:?} ({:?}) found={:?} ({:?})",
                     values.expected,
-                    values.expected.sty,
+                    values.expected.kind,
                     values.found,
-                    values.found.sty,
+                    values.found.kind,
                 );
             },
             CyclicTy(ty) => {
diff --git a/src/librustc/ty/fast_reject.rs b/src/librustc/ty/fast_reject.rs
index ee0d33dbe345c..7d6ae3f815af1 100644
--- a/src/librustc/ty/fast_reject.rs
+++ b/src/librustc/ty/fast_reject.rs
@@ -60,7 +60,7 @@ pub fn simplify_type(
     ty: Ty<'_>,
     can_simplify_params: bool,
 ) -> Option<SimplifiedType> {
-    match ty.sty {
+    match ty.kind {
         ty::Bool => Some(BoolSimplifiedType),
         ty::Char => Some(CharSimplifiedType),
         ty::Int(int_type) => Some(IntSimplifiedType(int_type)),
diff --git a/src/librustc/ty/fold.rs b/src/librustc/ty/fold.rs
index 1e08ae45951d1..f6a5092d30d40 100644
--- a/src/librustc/ty/fold.rs
+++ b/src/librustc/ty/fold.rs
@@ -472,7 +472,7 @@ impl<'a, 'tcx> TypeFolder<'tcx> for BoundVarReplacer<'a, 'tcx> {
     }
 
     fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
-        match t.sty {
+        match t.kind {
             ty::Bound(debruijn, bound_ty) => {
                 if debruijn == self.current_index {
                     let fld_t = &mut self.fld_t;
@@ -776,7 +776,7 @@ impl TypeFolder<'tcx> for Shifter<'tcx> {
     }
 
     fn fold_ty(&mut self, ty: Ty<'tcx>) -> Ty<'tcx> {
-        match ty.sty {
+        match ty.kind {
             ty::Bound(debruijn, bound_ty) => {
                 if self.amount == 0 || debruijn < self.current_index {
                     ty
@@ -985,7 +985,7 @@ impl<'tcx> TypeVisitor<'tcx> for LateBoundRegionsCollector {
         // ignore the inputs to a projection, as they may not appear
         // in the normalized form
         if self.just_constrained {
-            match t.sty {
+            match t.kind {
                 ty::Projection(..) | ty::Opaque(..) => { return false; }
                 _ => { }
             }
diff --git a/src/librustc/ty/inhabitedness/mod.rs b/src/librustc/ty/inhabitedness/mod.rs
index 1a0e351733877..bc0cf4deaa47b 100644
--- a/src/librustc/ty/inhabitedness/mod.rs
+++ b/src/librustc/ty/inhabitedness/mod.rs
@@ -181,7 +181,7 @@ impl<'tcx> FieldDef {
 impl<'tcx> TyS<'tcx> {
     /// Calculates the forest of `DefId`s from which this type is visibly uninhabited.
     fn uninhabited_from(&self, tcx: TyCtxt<'tcx>) -> DefIdForest {
-        match self.sty {
+        match self.kind {
             Adt(def, substs) => def.uninhabited_from(tcx, substs),
 
             Never => DefIdForest::full(tcx),
diff --git a/src/librustc/ty/instance.rs b/src/librustc/ty/instance.rs
index a26fa72f33041..ecb512b0cd1a2 100644
--- a/src/librustc/ty/instance.rs
+++ b/src/librustc/ty/instance.rs
@@ -54,7 +54,7 @@ impl<'tcx> Instance<'tcx> {
 
     fn fn_sig_noadjust(&self, tcx: TyCtxt<'tcx>) -> PolyFnSig<'tcx> {
         let ty = self.ty(tcx);
-        match ty.sty {
+        match ty.kind {
             ty::FnDef(..) |
             // Shims currently have type FnPtr. Not sure this should remain.
             ty::FnPtr(_) => ty.fn_sig(tcx),
@@ -255,7 +255,7 @@ impl<'tcx> Instance<'tcx> {
                 &ty,
             );
 
-            let def = match item_type.sty {
+            let def = match item_type.kind {
                 ty::FnDef(..) if {
                     let f = item_type.fn_sig(tcx);
                     f.abi() == Abi::RustIntrinsic ||
diff --git a/src/librustc/ty/layout.rs b/src/librustc/ty/layout.rs
index e52feea1624c1..790b0c5cb48f4 100644
--- a/src/librustc/ty/layout.rs
+++ b/src/librustc/ty/layout.rs
@@ -520,7 +520,7 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
         };
         debug_assert!(!ty.has_infer_types());
 
-        Ok(match ty.sty {
+        Ok(match ty.kind {
             // Basic scalars.
             ty::Bool => {
                 tcx.intern_layout(LayoutDetails::scalar(self, Scalar {
@@ -573,7 +573,7 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
                 }
 
                 let unsized_part = tcx.struct_tail_erasing_lifetimes(pointee, param_env);
-                let metadata = match unsized_part.sty {
+                let metadata = match unsized_part.kind {
                     ty::Foreign(..) => {
                         return Ok(tcx.intern_layout(LayoutDetails::scalar(self, data_ptr)));
                     }
@@ -1618,7 +1618,7 @@ impl<'tcx> LayoutCx<'tcx, TyCtxt<'tcx>> {
                                                                    variants);
         };
 
-        let adt_def = match layout.ty.sty {
+        let adt_def = match layout.ty.kind {
             ty::Adt(ref adt_def, _) => {
                 debug!("print-type-size t: `{:?}` process adt", layout.ty);
                 adt_def
@@ -1759,12 +1759,12 @@ impl<'tcx> SizeSkeleton<'tcx> {
             Err(err) => err
         };
 
-        match ty.sty {
+        match ty.kind {
             ty::Ref(_, pointee, _) |
             ty::RawPtr(ty::TypeAndMut { ty: pointee, .. }) => {
                 let non_zero = !ty.is_unsafe_ptr();
                 let tail = tcx.struct_tail_erasing_lifetimes(pointee, param_env);
-                match tail.sty {
+                match tail.kind {
                     ty::Param(_) | ty::Projection(_) => {
                         debug_assert!(tail.has_param_types());
                         Ok(SizeSkeleton::Pointer {
@@ -2040,7 +2040,7 @@ where
                     assert_eq!(layout.variants, Variants::Single { index });
                 }
 
-                let fields = match this.ty.sty {
+                let fields = match this.ty.kind {
                     ty::Adt(def, _) => def.variants[variant_index].fields.len(),
                     _ => bug!()
                 };
@@ -2078,7 +2078,7 @@ where
             }))
         };
 
-        cx.layout_of(match this.ty.sty {
+        cx.layout_of(match this.ty.kind {
             ty::Bool |
             ty::Char |
             ty::Int(_) |
@@ -2115,7 +2115,7 @@ where
                     }));
                 }
 
-                match tcx.struct_tail_erasing_lifetimes(pointee, cx.param_env()).sty {
+                match tcx.struct_tail_erasing_lifetimes(pointee, cx.param_env()).kind {
                     ty::Slice(_) |
                     ty::Str => tcx.types.usize,
                     ty::Dynamic(_, _) => {
@@ -2202,7 +2202,7 @@ where
         cx: &C,
         offset: Size,
     ) -> Option<PointeeInfo> {
-        match this.ty.sty {
+        match this.ty.kind {
             ty::RawPtr(mt) if offset.bytes() == 0 => {
                 cx.layout_of(mt.ty).to_result().ok()
                     .map(|layout| PointeeInfo {
@@ -2309,7 +2309,7 @@ where
 
                 // FIXME(eddyb) This should be for `ptr::Unique<T>`, not `Box<T>`.
                 if let Some(ref mut pointee) = result {
-                    if let ty::Adt(def, _) = this.ty.sty {
+                    if let ty::Adt(def, _) = this.ty.kind {
                         if def.is_box() && offset.bytes() == 0 {
                             pointee.safe = Some(PointerKind::UniqueOwned);
                         }
@@ -2641,7 +2641,7 @@ where
         let extra_args = if sig.abi == RustCall {
             assert!(!sig.c_variadic && extra_args.is_empty());
 
-            match sig.inputs().last().unwrap().sty {
+            match sig.inputs().last().unwrap().kind {
                 ty::Tuple(tupled_arguments) => {
                     inputs = &sig.inputs()[0..sig.inputs().len() - 1];
                     tupled_arguments.iter().map(|k| k.expect_ty()).collect()
@@ -2753,7 +2753,7 @@ where
                             Some(did) => did,
                             None => bug!("`va_list` lang item required for C-variadic functions"),
                         };
-                        match ty.sty {
+                        match ty.kind {
                             ty::Adt(def, _) if def.did == va_list_did => {
                                 // This is the "spoofed" `VaListImpl`. Set the arguments mode
                                 // so that it will be ignored.
diff --git a/src/librustc/ty/mod.rs b/src/librustc/ty/mod.rs
index 61483fa8a498e..bd5ac5e5ab478 100644
--- a/src/librustc/ty/mod.rs
+++ b/src/librustc/ty/mod.rs
@@ -167,6 +167,19 @@ pub struct ImplHeader<'tcx> {
     pub predicates: Vec<Predicate<'tcx>>,
 }
 
+#[derive(Copy, Clone, PartialEq, RustcEncodable, RustcDecodable, HashStable)]
+pub enum ImplPolarity {
+    /// `impl Trait for Type`
+    Positive,
+    /// `impl !Trait for Type`
+    Negative,
+    /// `#[rustc_reservation_impl] impl Trait for Type`
+    ///
+    /// This is a "stability hack", not a real Rust feature.
+    /// See #64631 for details.
+    Reservation,
+}
+
 #[derive(Copy, Clone, Debug, PartialEq, HashStable)]
 pub struct AssocItem {
     pub def_id: DefId,
@@ -479,7 +492,7 @@ bitflags! {
 
 #[allow(rustc::usage_of_ty_tykind)]
 pub struct TyS<'tcx> {
-    pub sty: TyKind<'tcx>,
+    pub kind: TyKind<'tcx>,
     pub flags: TypeFlags,
 
     /// This is a kind of confusing thing: it stores the smallest
@@ -508,13 +521,13 @@ static_assert_size!(TyS<'_>, 32);
 
 impl<'tcx> Ord for TyS<'tcx> {
     fn cmp(&self, other: &TyS<'tcx>) -> Ordering {
-        self.sty.cmp(&other.sty)
+        self.kind.cmp(&other.kind)
     }
 }
 
 impl<'tcx> PartialOrd for TyS<'tcx> {
     fn partial_cmp(&self, other: &TyS<'tcx>) -> Option<Ordering> {
-        Some(self.sty.cmp(&other.sty))
+        Some(self.kind.cmp(&other.kind))
     }
 }
 
@@ -534,7 +547,7 @@ impl<'tcx> Hash for TyS<'tcx> {
 
 impl<'tcx> TyS<'tcx> {
     pub fn is_primitive_ty(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Bool |
             Char |
             Int(_) |
@@ -550,7 +563,7 @@ impl<'tcx> TyS<'tcx> {
     }
 
     pub fn is_suggestable(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Opaque(..) |
             FnDef(..) |
             FnPtr(..) |
@@ -568,16 +581,16 @@ impl<'a, 'tcx> HashStable<StableHashingContext<'a>> for ty::TyS<'tcx> {
                                           hcx: &mut StableHashingContext<'a>,
                                           hasher: &mut StableHasher<W>) {
         let ty::TyS {
-            ref sty,
+            ref kind,
 
             // The other fields just provide fast access to information that is
-            // also contained in `sty`, so no need to hash them.
+            // also contained in `kind`, so no need to hash them.
             flags: _,
 
             outer_exclusive_binder: _,
         } = *self;
 
-        sty.hash_stable(hcx, hasher);
+        kind.hash_stable(hcx, hasher);
     }
 }
 
@@ -2494,7 +2507,7 @@ impl<'tcx> AdtDef {
     }
 
     fn sized_constraint_for_ty(&self, tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> Vec<Ty<'tcx>> {
-        let result = match ty.sty {
+        let result = match ty.kind {
             Bool | Char | Int(..) | Uint(..) | Float(..) |
             RawPtr(..) | Ref(..) | FnDef(..) | FnPtr(_) |
             Array(..) | Closure(..) | Generator(..) | Never => {
@@ -2911,7 +2924,26 @@ impl<'tcx> TyCtxt<'tcx> {
             return Some(ImplOverlapKind::Permitted);
         }
 
-        let is_legit = if self.features().overlapping_marker_traits {
+        match (self.impl_polarity(def_id1), self.impl_polarity(def_id2)) {
+            (ImplPolarity::Reservation, _) |
+            (_, ImplPolarity::Reservation) => {
+                // `#[rustc_reservation_impl]` impls don't overlap with anything
+                debug!("impls_are_allowed_to_overlap({:?}, {:?}) = Some(Permitted) (reservations)",
+                       def_id1, def_id2);
+                return Some(ImplOverlapKind::Permitted);
+            }
+            (ImplPolarity::Positive, ImplPolarity::Negative) |
+            (ImplPolarity::Negative, ImplPolarity::Positive) => {
+                // `impl AutoTrait for Type` + `impl !AutoTrait for Type`
+                debug!("impls_are_allowed_to_overlap({:?}, {:?}) - None (differing polarities)",
+                       def_id1, def_id2);
+                return None;
+            }
+            (ImplPolarity::Positive, ImplPolarity::Positive) |
+            (ImplPolarity::Negative, ImplPolarity::Negative) => {}
+        };
+
+        let is_marker_overlap = if self.features().overlapping_marker_traits {
             let trait1_is_empty = self.impl_trait_ref(def_id1)
                 .map_or(false, |trait_ref| {
                     self.associated_item_def_ids(trait_ref.def_id).is_empty()
@@ -2920,22 +2952,19 @@ impl<'tcx> TyCtxt<'tcx> {
                 .map_or(false, |trait_ref| {
                     self.associated_item_def_ids(trait_ref.def_id).is_empty()
                 });
-            self.impl_polarity(def_id1) == self.impl_polarity(def_id2)
-                && trait1_is_empty
-                && trait2_is_empty
+            trait1_is_empty && trait2_is_empty
         } else {
             let is_marker_impl = |def_id: DefId| -> bool {
                 let trait_ref = self.impl_trait_ref(def_id);
                 trait_ref.map_or(false, |tr| self.trait_def(tr.def_id).is_marker)
             };
-            self.impl_polarity(def_id1) == self.impl_polarity(def_id2)
-                && is_marker_impl(def_id1)
-                && is_marker_impl(def_id2)
+            is_marker_impl(def_id1) && is_marker_impl(def_id2)
         };
 
-        if is_legit {
-            debug!("impls_are_allowed_to_overlap({:?}, {:?}) = Some(Permitted)",
-                  def_id1, def_id2);
+
+        if is_marker_overlap {
+            debug!("impls_are_allowed_to_overlap({:?}, {:?}) = Some(Permitted) (marker overlap)",
+                   def_id1, def_id2);
             Some(ImplOverlapKind::Permitted)
         } else {
             if let Some(self_ty1) = self.issue33140_self_ty(def_id1) {
@@ -3317,7 +3346,7 @@ fn issue33140_self_ty(tcx: TyCtxt<'_>, def_id: DefId) -> Option<Ty<'_>> {
     debug!("issue33140_self_ty({:?}), trait-ref={:?}", def_id, trait_ref);
 
     let is_marker_like =
-        tcx.impl_polarity(def_id) == hir::ImplPolarity::Positive &&
+        tcx.impl_polarity(def_id) == ty::ImplPolarity::Positive &&
         tcx.associated_item_def_ids(trait_ref.def_id).is_empty();
 
     // Check whether these impls would be ok for a marker trait.
@@ -3339,7 +3368,7 @@ fn issue33140_self_ty(tcx: TyCtxt<'_>, def_id: DefId) -> Option<Ty<'_>> {
     }
 
     let self_ty = trait_ref.self_ty();
-    let self_ty_matches = match self_ty.sty {
+    let self_ty_matches = match self_ty.kind {
         ty::Dynamic(ref data, ty::ReStatic) => data.principal().is_none(),
         _ => false
     };
diff --git a/src/librustc/ty/outlives.rs b/src/librustc/ty/outlives.rs
index 7d1403d1e9662..9a2e30f7f45ed 100644
--- a/src/librustc/ty/outlives.rs
+++ b/src/librustc/ty/outlives.rs
@@ -60,7 +60,7 @@ impl<'tcx> TyCtxt<'tcx> {
         // with `collect()` because of the need to sometimes skip subtrees
         // in the `subtys` iterator (e.g., when encountering a
         // projection).
-        match ty.sty {
+        match ty.kind {
             ty::Closure(def_id, ref substs) => {
                 for upvar_ty in substs.upvar_tys(def_id, *self) {
                     self.compute_components(upvar_ty, out);
diff --git a/src/librustc/ty/print/mod.rs b/src/librustc/ty/print/mod.rs
index 50789bf6213b6..727397d7a29ab 100644
--- a/src/librustc/ty/print/mod.rs
+++ b/src/librustc/ty/print/mod.rs
@@ -266,7 +266,7 @@ pub trait Printer<'tcx>: Sized {
 /// type. It's just a heuristic so it makes some questionable
 /// decisions and we may want to adjust it later.
 pub fn characteristic_def_id_of_type(ty: Ty<'_>) -> Option<DefId> {
-    match ty.sty {
+    match ty.kind {
         ty::Adt(adt_def, _) => Some(adt_def.did),
 
         ty::Dynamic(data, ..) => data.principal_def_id(),
diff --git a/src/librustc/ty/print/obsolete.rs b/src/librustc/ty/print/obsolete.rs
index b68e6a744872f..d7d43b8203f6f 100644
--- a/src/librustc/ty/print/obsolete.rs
+++ b/src/librustc/ty/print/obsolete.rs
@@ -34,7 +34,7 @@ impl DefPathBasedNames<'tcx> {
     // When being used for codegen purposes, `debug` should be set to `false`
     // in order to catch unexpected types that should never end up in a type name.
     pub fn push_type_name(&self, t: Ty<'tcx>, output: &mut String, debug: bool) {
-        match t.sty {
+        match t.kind {
             ty::Bool => output.push_str("bool"),
             ty::Char => output.push_str("char"),
             ty::Str => output.push_str("str"),
diff --git a/src/librustc/ty/print/pretty.rs b/src/librustc/ty/print/pretty.rs
index d99580116e4ae..a38a00ff5b759 100644
--- a/src/librustc/ty/print/pretty.rs
+++ b/src/librustc/ty/print/pretty.rs
@@ -414,7 +414,7 @@ pub trait PrettyPrinter<'tcx>:
             // Inherent impls. Try to print `Foo::bar` for an inherent
             // impl on `Foo`, but fallback to `<Foo>::bar` if self-type is
             // anything other than a simple path.
-            match self_ty.sty {
+            match self_ty.kind {
                 ty::Adt(..) | ty::Foreign(_) |
                 ty::Bool | ty::Char | ty::Str |
                 ty::Int(_) | ty::Uint(_) | ty::Float(_) => {
@@ -463,7 +463,7 @@ pub trait PrettyPrinter<'tcx>:
     ) -> Result<Self::Type, Self::Error> {
         define_scoped_cx!(self);
 
-        match ty.sty {
+        match ty.kind {
             ty::Bool => p!(write("bool")),
             ty::Char => p!(write("char")),
             ty::Int(t) => p!(write("{}", t.ty_to_string())),
@@ -739,7 +739,7 @@ pub trait PrettyPrinter<'tcx>:
             // Special-case `Fn(...) -> ...` and resugar it.
             let fn_trait_kind = self.tcx().lang_items().fn_trait_kind(principal.def_id);
             if !self.tcx().sess.verbose() && fn_trait_kind.is_some() {
-                if let ty::Tuple(ref args) = principal.substs.type_at(0).sty {
+                if let ty::Tuple(ref args) = principal.substs.type_at(0).kind {
                     let mut projections = predicates.projection_bounds();
                     if let (Some(proj), None) = (projections.next(), projections.next()) {
                         let tys: Vec<_> = args.iter().map(|k| k.expect_ty()).collect();
@@ -856,7 +856,7 @@ pub trait PrettyPrinter<'tcx>:
         define_scoped_cx!(self);
 
         let u8 = self.tcx().types.u8;
-        if let ty::FnDef(did, substs) = ct.ty.sty {
+        if let ty::FnDef(did, substs) = ct.ty.kind {
             p!(print_value_path(did, substs));
             return Ok(self);
         }
@@ -887,7 +887,7 @@ pub trait PrettyPrinter<'tcx>:
             return Ok(self);
         }
         if let ConstValue::Scalar(Scalar::Raw { data, .. }) = ct.val {
-            match ct.ty.sty {
+            match ct.ty.kind {
                 ty::Bool => {
                     p!(write("{}", if data == 0 { "false" } else { "true" }));
                     return Ok(self);
@@ -935,8 +935,8 @@ pub trait PrettyPrinter<'tcx>:
                 _ => {},
             }
         }
-        if let ty::Ref(_, ref_ty, _) = ct.ty.sty {
-            let byte_str = match (ct.val, &ref_ty.sty) {
+        if let ty::Ref(_, ref_ty, _) = ct.ty.kind {
+            let byte_str = match (ct.val, &ref_ty.kind) {
                 (ConstValue::Scalar(Scalar::Ptr(ptr)), ty::Array(t, n)) if *t == u8 => {
                     let n = n.eval_usize(self.tcx(), ty::ParamEnv::empty());
                     Some(self.tcx()
diff --git a/src/librustc/ty/relate.rs b/src/librustc/ty/relate.rs
index 565447dd7e1af..d6bd4eeb7367a 100644
--- a/src/librustc/ty/relate.rs
+++ b/src/librustc/ty/relate.rs
@@ -349,7 +349,7 @@ pub fn super_relate_tys<R: TypeRelation<'tcx>>(
 ) -> RelateResult<'tcx, Ty<'tcx>> {
     let tcx = relation.tcx();
     debug!("super_relate_tys: a={:?} b={:?}", a, b);
-    match (&a.sty, &b.sty) {
+    match (&a.kind, &b.kind) {
         (&ty::Infer(_), _) |
         (_, &ty::Infer(_)) =>
         {
diff --git a/src/librustc/ty/structural_impls.rs b/src/librustc/ty/structural_impls.rs
index ec7cf1a13c596..42d632d120ea1 100644
--- a/src/librustc/ty/structural_impls.rs
+++ b/src/librustc/ty/structural_impls.rs
@@ -1023,7 +1023,7 @@ impl<'tcx> TypeFoldable<'tcx> for interpret::GlobalId<'tcx> {
 
 impl<'tcx> TypeFoldable<'tcx> for Ty<'tcx> {
     fn super_fold_with<F: TypeFolder<'tcx>>(&self, folder: &mut F) -> Self {
-        let sty = match self.sty {
+        let kind = match self.kind {
             ty::RawPtr(tm) => ty::RawPtr(tm.fold_with(folder)),
             ty::Array(typ, sz) => ty::Array(typ.fold_with(folder), sz.fold_with(folder)),
             ty::Slice(typ) => ty::Slice(typ.fold_with(folder)),
@@ -1064,13 +1064,13 @@ impl<'tcx> TypeFoldable<'tcx> for Ty<'tcx> {
             ty::Bound(..) |
             ty::Placeholder(..) |
             ty::Never |
-            ty::Foreign(..) => return self
+            ty::Foreign(..) => return self,
         };
 
-        if self.sty == sty {
+        if self.kind == kind {
             self
         } else {
-            folder.tcx().mk_ty(sty)
+            folder.tcx().mk_ty(kind)
         }
     }
 
@@ -1079,7 +1079,7 @@ impl<'tcx> TypeFoldable<'tcx> for Ty<'tcx> {
     }
 
     fn super_visit_with<V: TypeVisitor<'tcx>>(&self, visitor: &mut V) -> bool {
-        match self.sty {
+        match self.kind {
             ty::RawPtr(ref tm) => tm.visit_with(visitor),
             ty::Array(typ, sz) => typ.visit_with(visitor) || sz.visit_with(visitor),
             ty::Slice(typ) => typ.visit_with(visitor),
diff --git a/src/librustc/ty/sty.rs b/src/librustc/ty/sty.rs
index 036f41a4043d4..6510aea8c256d 100644
--- a/src/librustc/ty/sty.rs
+++ b/src/librustc/ty/sty.rs
@@ -384,9 +384,9 @@ impl<'tcx> ClosureSubsts<'tcx> {
     /// If you have an inference context, use `infcx.closure_sig()`.
     pub fn closure_sig(self, def_id: DefId, tcx: TyCtxt<'tcx>) -> ty::PolyFnSig<'tcx> {
         let ty = self.closure_sig_ty(def_id, tcx);
-        match ty.sty {
+        match ty.kind {
             ty::FnPtr(sig) => sig,
-            _ => bug!("closure_sig_ty is not a fn-ptr: {:?}", ty.sty),
+            _ => bug!("closure_sig_ty is not a fn-ptr: {:?}", ty.kind),
         }
     }
 }
@@ -1678,7 +1678,7 @@ impl RegionKind {
 impl<'tcx> TyS<'tcx> {
     #[inline]
     pub fn is_unit(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Tuple(ref tys) => tys.is_empty(),
             _ => false,
         }
@@ -1686,7 +1686,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_never(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Never => true,
             _ => false,
         }
@@ -1701,7 +1701,7 @@ impl<'tcx> TyS<'tcx> {
     pub fn conservative_is_privately_uninhabited(&self, tcx: TyCtxt<'tcx>) -> bool {
         // FIXME(varkor): we can make this less conversative by substituting concrete
         // type arguments.
-        match self.sty {
+        match self.kind {
             ty::Never => true,
             ty::Adt(def, _) if def.is_union() => {
                 // For now, `union`s are never considered uninhabited.
@@ -1741,7 +1741,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_primitive(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Bool | Char | Int(_) | Uint(_) | Float(_) => true,
             _ => false,
         }
@@ -1749,7 +1749,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_ty_var(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Infer(TyVar(_)) => true,
             _ => false,
         }
@@ -1757,7 +1757,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_ty_infer(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Infer(_) => true,
             _ => false,
         }
@@ -1765,7 +1765,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_phantom_data(&self) -> bool {
-        if let Adt(def, _) = self.sty {
+        if let Adt(def, _) = self.kind {
             def.is_phantom_data()
         } else {
             false
@@ -1773,11 +1773,11 @@ impl<'tcx> TyS<'tcx> {
     }
 
     #[inline]
-    pub fn is_bool(&self) -> bool { self.sty == Bool }
+    pub fn is_bool(&self) -> bool { self.kind == Bool }
 
     #[inline]
     pub fn is_param(&self, index: u32) -> bool {
-        match self.sty {
+        match self.kind {
             ty::Param(ref data) => data.index == index,
             _ => false,
         }
@@ -1785,8 +1785,8 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_slice(&self) -> bool {
-        match self.sty {
-            RawPtr(TypeAndMut { ty, .. }) | Ref(_, ty, _) => match ty.sty {
+        match self.kind {
+            RawPtr(TypeAndMut { ty, .. }) | Ref(_, ty, _) => match ty.kind {
                 Slice(_) | Str => true,
                 _ => false,
             },
@@ -1796,14 +1796,14 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_simd(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Adt(def, _) => def.repr.simd(),
             _ => false,
         }
     }
 
     pub fn sequence_element_type(&self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
-        match self.sty {
+        match self.kind {
             Array(ty, _) | Slice(ty) => ty,
             Str => tcx.mk_mach_uint(ast::UintTy::U8),
             _ => bug!("sequence_element_type called on non-sequence value: {}", self),
@@ -1811,7 +1811,7 @@ impl<'tcx> TyS<'tcx> {
     }
 
     pub fn simd_type(&self, tcx: TyCtxt<'tcx>) -> Ty<'tcx> {
-        match self.sty {
+        match self.kind {
             Adt(def, substs) => {
                 def.non_enum_variant().fields[0].ty(tcx, substs)
             }
@@ -1820,7 +1820,7 @@ impl<'tcx> TyS<'tcx> {
     }
 
     pub fn simd_size(&self, _cx: TyCtxt<'_>) -> usize {
-        match self.sty {
+        match self.kind {
             Adt(def, _) => def.non_enum_variant().fields.len(),
             _ => bug!("simd_size called on invalid type")
         }
@@ -1828,7 +1828,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_region_ptr(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Ref(..) => true,
             _ => false,
         }
@@ -1836,7 +1836,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_mutable_ptr(&self) -> bool {
-        match self.sty {
+        match self.kind {
             RawPtr(TypeAndMut { mutbl: hir::Mutability::MutMutable, .. }) |
             Ref(_, _, hir::Mutability::MutMutable) => true,
             _ => false
@@ -1845,7 +1845,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_unsafe_ptr(&self) -> bool {
-        match self.sty {
+        match self.kind {
             RawPtr(_) => return true,
             _ => return false,
         }
@@ -1860,7 +1860,7 @@ impl<'tcx> TyS<'tcx> {
     /// Returns `true` if this type is an `Arc<T>`.
     #[inline]
     pub fn is_arc(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Adt(def, _) => def.is_arc(),
             _ => false,
         }
@@ -1869,7 +1869,7 @@ impl<'tcx> TyS<'tcx> {
     /// Returns `true` if this type is an `Rc<T>`.
     #[inline]
     pub fn is_rc(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Adt(def, _) => def.is_rc(),
             _ => false,
         }
@@ -1877,7 +1877,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_box(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Adt(def, _) => def.is_box(),
             _ => false,
         }
@@ -1885,7 +1885,7 @@ impl<'tcx> TyS<'tcx> {
 
     /// panics if called on any type other than `Box<T>`
     pub fn boxed_ty(&self) -> Ty<'tcx> {
-        match self.sty {
+        match self.kind {
             Adt(def, substs) if def.is_box() => substs.type_at(0),
             _ => bug!("`boxed_ty` is called on non-box type {:?}", self),
         }
@@ -1896,7 +1896,7 @@ impl<'tcx> TyS<'tcx> {
     /// contents are abstract to rustc.)
     #[inline]
     pub fn is_scalar(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Bool | Char | Int(_) | Float(_) | Uint(_) |
             Infer(IntVar(_)) | Infer(FloatVar(_)) |
             FnDef(..) | FnPtr(_) | RawPtr(_) => true,
@@ -1907,7 +1907,7 @@ impl<'tcx> TyS<'tcx> {
     /// Returns `true` if this type is a floating point type.
     #[inline]
     pub fn is_floating_point(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Float(_) |
             Infer(FloatVar(_)) => true,
             _ => false,
@@ -1916,7 +1916,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_trait(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Dynamic(..) => true,
             _ => false,
         }
@@ -1924,7 +1924,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_enum(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Adt(adt_def, _) => {
                 adt_def.is_enum()
             }
@@ -1934,7 +1934,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_closure(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Closure(..) => true,
             _ => false,
         }
@@ -1942,7 +1942,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_generator(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Generator(..) => true,
             _ => false,
         }
@@ -1950,7 +1950,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_integral(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Infer(IntVar(_)) | Int(_) | Uint(_) => true,
             _ => false
         }
@@ -1958,7 +1958,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_fresh_ty(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Infer(FreshTy(_)) => true,
             _ => false,
         }
@@ -1966,7 +1966,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_fresh(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Infer(FreshTy(_)) => true,
             Infer(FreshIntTy(_)) => true,
             Infer(FreshFloatTy(_)) => true,
@@ -1976,7 +1976,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_char(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Char => true,
             _ => false,
         }
@@ -1989,7 +1989,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_signed(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Int(_) => true,
             _ => false,
         }
@@ -1997,7 +1997,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_ptr_sized_integral(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Int(ast::IntTy::Isize) | Uint(ast::UintTy::Usize) => true,
             _ => false,
         }
@@ -2005,7 +2005,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_machine(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Int(..) | Uint(..) | Float(..) => true,
             _ => false,
         }
@@ -2013,7 +2013,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn has_concrete_skeleton(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Param(_) | Infer(_) | Error => false,
             _ => true,
         }
@@ -2024,7 +2024,7 @@ impl<'tcx> TyS<'tcx> {
     /// The parameter `explicit` indicates if this is an *explicit* dereference.
     /// Some types -- notably unsafe ptrs -- can only be dereferenced explicitly.
     pub fn builtin_deref(&self, explicit: bool) -> Option<TypeAndMut<'tcx>> {
-        match self.sty {
+        match self.kind {
             Adt(def, _) if def.is_box() => {
                 Some(TypeAndMut {
                     ty: self.boxed_ty(),
@@ -2039,14 +2039,14 @@ impl<'tcx> TyS<'tcx> {
 
     /// Returns the type of `ty[i]`.
     pub fn builtin_index(&self) -> Option<Ty<'tcx>> {
-        match self.sty {
+        match self.kind {
             Array(ty, _) | Slice(ty) => Some(ty),
             _ => None,
         }
     }
 
     pub fn fn_sig(&self, tcx: TyCtxt<'tcx>) -> PolyFnSig<'tcx> {
-        match self.sty {
+        match self.kind {
             FnDef(def_id, substs) => {
                 tcx.fn_sig(def_id).subst(tcx, substs)
             }
@@ -2063,7 +2063,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_fn(&self) -> bool {
-        match self.sty {
+        match self.kind {
             FnDef(..) | FnPtr(_) => true,
             _ => false,
         }
@@ -2071,7 +2071,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_fn_ptr(&self) -> bool {
-        match self.sty {
+        match self.kind {
             FnPtr(_) => true,
             _ => false,
         }
@@ -2079,7 +2079,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn is_impl_trait(&self) -> bool {
-        match self.sty {
+        match self.kind {
             Opaque(..) => true,
             _ => false,
         }
@@ -2087,7 +2087,7 @@ impl<'tcx> TyS<'tcx> {
 
     #[inline]
     pub fn ty_adt_def(&self) -> Option<&'tcx AdtDef> {
-        match self.sty {
+        match self.kind {
             Adt(adt, _) => Some(adt),
             _ => None,
         }
@@ -2096,7 +2096,7 @@ impl<'tcx> TyS<'tcx> {
     /// Iterates over tuple fields.
     /// Panics when called on anything but a tuple.
     pub fn tuple_fields(&self) -> impl DoubleEndedIterator<Item=Ty<'tcx>> {
-        match self.sty {
+        match self.kind {
             Tuple(substs) => substs.iter().map(|field| field.expect_ty()),
             _ => bug!("tuple_fields called on non-tuple"),
         }
@@ -2106,7 +2106,7 @@ impl<'tcx> TyS<'tcx> {
     /// FIXME This requires the optimized MIR in the case of generators.
     #[inline]
     pub fn variant_range(&self, tcx: TyCtxt<'tcx>) -> Option<Range<VariantIdx>> {
-        match self.sty {
+        match self.kind {
             TyKind::Adt(adt, _) => Some(adt.variant_range()),
             TyKind::Generator(def_id, substs, _) => Some(substs.variant_range(def_id, tcx)),
             _ => None,
@@ -2122,7 +2122,7 @@ impl<'tcx> TyS<'tcx> {
         tcx: TyCtxt<'tcx>,
         variant_index: VariantIdx,
     ) -> Option<Discr<'tcx>> {
-        match self.sty {
+        match self.kind {
             TyKind::Adt(adt, _) => Some(adt.discriminant_for_variant(tcx, variant_index)),
             TyKind::Generator(def_id, substs, _) =>
                 Some(substs.discriminant_for_variant(def_id, tcx, variant_index)),
@@ -2134,7 +2134,7 @@ impl<'tcx> TyS<'tcx> {
     /// types reachable from this type via `walk_tys`). This ignores late-bound
     /// regions binders.
     pub fn push_regions(&self, out: &mut SmallVec<[ty::Region<'tcx>; 4]>) {
-        match self.sty {
+        match self.kind {
             Ref(region, _, _) => {
                 out.push(region);
             }
@@ -2190,7 +2190,7 @@ impl<'tcx> TyS<'tcx> {
     /// inferred. Once upvar inference (in `src/librustc_typeck/check/upvar.rs`)
     /// is complete, that type variable will be unified.
     pub fn to_opt_closure_kind(&self) -> Option<ty::ClosureKind> {
-        match self.sty {
+        match self.kind {
             Int(int_ty) => match int_ty {
                 ast::IntTy::I8 => Some(ty::ClosureKind::Fn),
                 ast::IntTy::I16 => Some(ty::ClosureKind::FnMut),
@@ -2211,7 +2211,7 @@ impl<'tcx> TyS<'tcx> {
     /// Returning true means the type is known to be sized. Returning
     /// `false` means nothing -- could be sized, might not be.
     pub fn is_trivially_sized(&self, tcx: TyCtxt<'tcx>) -> bool {
-        match self.sty {
+        match self.kind {
             ty::Infer(ty::IntVar(_)) | ty::Infer(ty::FloatVar(_)) |
             ty::Uint(_) | ty::Int(_) | ty::Bool | ty::Float(_) |
             ty::FnDef(..) | ty::FnPtr(_) | ty::RawPtr(..) |
diff --git a/src/librustc/ty/subst.rs b/src/librustc/ty/subst.rs
index ea829da783e9b..b5debc179e923 100644
--- a/src/librustc/ty/subst.rs
+++ b/src/librustc/ty/subst.rs
@@ -501,7 +501,7 @@ impl<'a, 'tcx> TypeFolder<'tcx> for SubstFolder<'a, 'tcx> {
         }
         self.ty_stack_depth += 1;
 
-        let t1 = match t.sty {
+        let t1 = match t.kind {
             ty::Param(p) => {
                 self.ty_for_param(p, t)
             }
diff --git a/src/librustc/ty/util.rs b/src/librustc/ty/util.rs
index 78d94df4fa03b..714ebf4c42ff8 100644
--- a/src/librustc/ty/util.rs
+++ b/src/librustc/ty/util.rs
@@ -33,7 +33,7 @@ pub struct Discr<'tcx> {
 
 impl<'tcx> fmt::Display for Discr<'tcx> {
     fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
-        match self.ty.sty {
+        match self.ty.kind {
             ty::Int(ity) => {
                 let size = ty::tls::with(|tcx| {
                     Integer::from_attr(&tcx, SignedInt(ity)).size()
@@ -54,7 +54,7 @@ impl<'tcx> Discr<'tcx> {
         self.checked_add(tcx, 1).0
     }
     pub fn checked_add(self, tcx: TyCtxt<'tcx>, n: u128) -> (Self, bool) {
-        let (int, signed) = match self.ty.sty {
+        let (int, signed) = match self.ty.kind {
             Int(ity) => (Integer::from_attr(&tcx, SignedInt(ity)), true),
             Uint(uty) => (Integer::from_attr(&tcx, UnsignedInt(uty)), false),
             _ => bug!("non integer discriminant"),
@@ -179,7 +179,7 @@ impl<'tcx> ty::ParamEnv<'tcx> {
     ) -> Result<(), CopyImplementationError<'tcx>> {
         // FIXME: (@jroesch) float this code up
         tcx.infer_ctxt().enter(|infcx| {
-            let (adt, substs) = match self_type.sty {
+            let (adt, substs) = match self_type.kind {
                 // These types used to have a builtin impl.
                 // Now libcore provides that impl.
                 ty::Uint(_) | ty::Int(_) | ty::Bool | ty::Float(_) |
@@ -246,10 +246,10 @@ impl<'tcx> TyCtxt<'tcx> {
 
 impl<'tcx> TyCtxt<'tcx> {
     pub fn has_error_field(self, ty: Ty<'tcx>) -> bool {
-        if let ty::Adt(def, substs) = ty.sty {
+        if let ty::Adt(def, substs) = ty.kind {
             for field in def.all_fields() {
                 let field_ty = field.ty(self, substs);
-                if let Error = field_ty.sty {
+                if let Error = field_ty.kind {
                     return true;
                 }
             }
@@ -298,7 +298,7 @@ impl<'tcx> TyCtxt<'tcx> {
                                       -> Ty<'tcx>
     {
         loop {
-            match ty.sty {
+            match ty.kind {
                 ty::Adt(def, substs) => {
                     if !def.is_struct() {
                         break;
@@ -370,7 +370,7 @@ impl<'tcx> TyCtxt<'tcx> {
     {
         let (mut a, mut b) = (source, target);
         loop {
-            match (&a.sty, &b.sty) {
+            match (&a.kind, &b.kind) {
                 (&Adt(a_def, a_substs), &Adt(b_def, b_substs))
                         if a_def == b_def && a_def.is_struct() => {
                     if let Some(f) = a_def.non_enum_variant().fields.last() {
@@ -544,12 +544,12 @@ impl<'tcx> TyCtxt<'tcx> {
         // <P1, P2, P0>, and then look up which of the impl substs refer to
         // parameters marked as pure.
 
-        let impl_substs = match self.type_of(impl_def_id).sty {
+        let impl_substs = match self.type_of(impl_def_id).kind {
             ty::Adt(def_, substs) if def_ == def => substs,
             _ => bug!()
         };
 
-        let item_substs = match self.type_of(def.did).sty {
+        let item_substs = match self.type_of(def.did).kind {
             ty::Adt(def_, substs) if def_ == def => substs,
             _ => bug!()
         };
@@ -561,7 +561,7 @@ impl<'tcx> TyCtxt<'tcx> {
                         !impl_generics.region_param(ebr, self).pure_wrt_drop
                     }
                     UnpackedKind::Type(&ty::TyS {
-                        sty: ty::Param(ref pt), ..
+                        kind: ty::Param(ref pt), ..
                     }) => {
                         !impl_generics.type_param(pt, self).pure_wrt_drop
                     }
@@ -733,7 +733,7 @@ impl<'tcx> TyCtxt<'tcx> {
             }
 
             fn fold_ty(&mut self, t: Ty<'tcx>) -> Ty<'tcx> {
-                if let ty::Opaque(def_id, substs) = t.sty {
+                if let ty::Opaque(def_id, substs) = t.kind {
                     self.expand_opaque_ty(def_id, substs).unwrap_or(t)
                 } else {
                     t.super_fold_with(self)
@@ -811,7 +811,7 @@ impl<'tcx> ty::TyS<'tcx> {
     }
 
     pub fn same_type(a: Ty<'tcx>, b: Ty<'tcx>) -> bool {
-        match (&a.sty, &b.sty) {
+        match (&a.kind, &b.kind) {
             (&Adt(did_a, substs_a), &Adt(did_b, substs_b)) => {
                 if did_a != did_b {
                     return false;
@@ -846,7 +846,7 @@ impl<'tcx> ty::TyS<'tcx> {
             representable_cache: &mut FxHashMap<Ty<'tcx>, Representability>,
             ty: Ty<'tcx>,
         ) -> Representability {
-            match ty.sty {
+            match ty.kind {
                 Tuple(..) => {
                     // Find non representable
                     fold_repr(ty.tuple_fields().map(|ty| {
@@ -889,7 +889,7 @@ impl<'tcx> ty::TyS<'tcx> {
         }
 
         fn same_struct_or_enum<'tcx>(ty: Ty<'tcx>, def: &'tcx ty::AdtDef) -> bool {
-            match ty.sty {
+            match ty.kind {
                 Adt(ty_def, _) => {
                      ty_def == def
                 }
@@ -927,7 +927,7 @@ impl<'tcx> ty::TyS<'tcx> {
             representable_cache: &mut FxHashMap<Ty<'tcx>, Representability>,
             ty: Ty<'tcx>,
         ) -> Representability {
-            match ty.sty {
+            match ty.kind {
                 Adt(def, _) => {
                     {
                         // Iterate through stack of previously seen types.
@@ -1009,7 +1009,7 @@ impl<'tcx> ty::TyS<'tcx> {
     /// - `&'a *const &'b u8 -> *const &'b u8`
     pub fn peel_refs(&'tcx self) -> Ty<'tcx> {
         let mut ty = self;
-        while let Ref(_, inner_ty, _) = ty.sty {
+        while let Ref(_, inner_ty, _) = ty.kind {
             ty = inner_ty;
         }
         ty
@@ -1067,7 +1067,7 @@ fn needs_drop_raw<'tcx>(tcx: TyCtxt<'tcx>, query: ty::ParamEnvAnd<'tcx, Ty<'tcx>
 
     assert!(!ty.needs_infer());
 
-    NeedsDrop(match ty.sty {
+    NeedsDrop(match ty.kind {
         // Fast-path for primitive types
         ty::Infer(ty::FreshIntTy(_)) | ty::Infer(ty::FreshFloatTy(_)) |
         ty::Bool | ty::Int(_) | ty::Uint(_) | ty::Float(_) | ty::Never |
@@ -1170,7 +1170,7 @@ impl<'tcx> ExplicitSelf<'tcx> {
     {
         use self::ExplicitSelf::*;
 
-        match self_arg_ty.sty {
+        match self_arg_ty.kind {
             _ if is_self_ty(self_arg_ty) => ByValue,
             ty::Ref(region, ty, mutbl) if is_self_ty(ty) => {
                 ByReference(region, mutbl)
diff --git a/src/librustc/ty/walk.rs b/src/librustc/ty/walk.rs
index 8c3110792a8b4..12f0d80cd0e1c 100644
--- a/src/librustc/ty/walk.rs
+++ b/src/librustc/ty/walk.rs
@@ -69,7 +69,7 @@ pub fn walk_shallow(ty: Ty<'_>) -> smallvec::IntoIter<TypeWalkerArray<'_>> {
 // natural order one would expect (basically, the order of the
 // types as they are written).
 fn push_subtypes<'tcx>(stack: &mut TypeWalkerStack<'tcx>, parent_ty: Ty<'tcx>) {
-    match parent_ty.sty {
+    match parent_ty.kind {
         ty::Bool | ty::Char | ty::Int(_) | ty::Uint(_) | ty::Float(_) |
         ty::Str | ty::Infer(_) | ty::Param(_) | ty::Never | ty::Error |
         ty::Placeholder(..) | ty::Bound(..) | ty::Foreign(..) => {
diff --git a/src/librustc/ty/wf.rs b/src/librustc/ty/wf.rs
index d6de217f79c29..020926e7c8de8 100644
--- a/src/librustc/ty/wf.rs
+++ b/src/librustc/ty/wf.rs
@@ -236,7 +236,7 @@ impl<'a, 'tcx> WfPredicates<'a, 'tcx> {
         let mut subtys = ty0.walk();
         let param_env = self.param_env;
         while let Some(ty) = subtys.next() {
-            match ty.sty {
+            match ty.kind {
                 ty::Bool |
                 ty::Char |
                 ty::Int(..) |
@@ -407,7 +407,7 @@ impl<'a, 'tcx> WfPredicates<'a, 'tcx> {
                 //    is satisfied to ensure termination.)
                 ty::Infer(_) => {
                     let ty = self.infcx.shallow_resolve(ty);
-                    if let ty::Infer(_) = ty.sty { // not yet resolved...
+                    if let ty::Infer(_) = ty.kind { // not yet resolved...
                         if ty == ty0 { // ...this is the type we started from! no progress.
                             return false;
                         }
diff --git a/src/librustc_ast_borrowck/borrowck/check_loans.rs b/src/librustc_ast_borrowck/borrowck/check_loans.rs
index 3d824ee6ce1e8..fcede3eae976f 100644
--- a/src/librustc_ast_borrowck/borrowck/check_loans.rs
+++ b/src/librustc_ast_borrowck/borrowck/check_loans.rs
@@ -615,7 +615,7 @@ impl<'a, 'tcx> CheckLoanCtxt<'a, 'tcx> {
                 self.check_if_assigned_path_is_moved(id, lp_base);
             }
             LpExtend(ref lp_base, _, LpInterior(_, InteriorField(_))) => {
-                match lp_base.to_type().sty {
+                match lp_base.to_type().kind {
                     ty::Adt(def, _) if def.has_dtor(self.tcx()) => {
                         // In the case where the owner implements drop, then
                         // the path must be initialized to prevent a case of
diff --git a/src/librustc_ast_borrowck/borrowck/gather_loans/gather_moves.rs b/src/librustc_ast_borrowck/borrowck/gather_loans/gather_moves.rs
index 617161109b573..2239bf56bbed2 100644
--- a/src/librustc_ast_borrowck/borrowck/gather_loans/gather_moves.rs
+++ b/src/librustc_ast_borrowck/borrowck/gather_loans/gather_moves.rs
@@ -108,7 +108,7 @@ fn check_and_get_illegal_move_origin<'a, 'tcx>(bccx: &BorrowckCtxt<'a, 'tcx>,
         Categorization::Downcast(ref b, _) |
         Categorization::Interior(ref b, mc::InteriorField(_)) |
         Categorization::Interior(ref b, mc::InteriorElement(Kind::Pattern)) => {
-            match b.ty.sty {
+            match b.ty.kind {
                 ty::Adt(def, _) => {
                     if def.has_dtor(bccx.tcx) {
                         Some(cmt.clone())
diff --git a/src/librustc_ast_borrowck/borrowck/gather_loans/restrictions.rs b/src/librustc_ast_borrowck/borrowck/gather_loans/restrictions.rs
index 545c27b17bd58..ee5099a97d57f 100644
--- a/src/librustc_ast_borrowck/borrowck/gather_loans/restrictions.rs
+++ b/src/librustc_ast_borrowck/borrowck/gather_loans/restrictions.rs
@@ -89,7 +89,7 @@ impl<'a, 'tcx> RestrictionsContext<'a, 'tcx> {
                 let base_ty = cmt_base.ty;
                 let result = self.restrict(&cmt_base);
                 // Borrowing one union field automatically borrows all its fields.
-                match base_ty.sty {
+                match base_ty.kind {
                     ty::Adt(adt_def, _) if adt_def.is_union() => match result {
                         RestrictionResult::Safe => RestrictionResult::Safe,
                         RestrictionResult::SafeIf(base_lp, mut base_vec) => {
diff --git a/src/librustc_ast_borrowck/borrowck/move_data.rs b/src/librustc_ast_borrowck/borrowck/move_data.rs
index 67d818161b1b5..6bc42348bcf6c 100644
--- a/src/librustc_ast_borrowck/borrowck/move_data.rs
+++ b/src/librustc_ast_borrowck/borrowck/move_data.rs
@@ -309,7 +309,7 @@ impl MoveData<'tcx> {
         let mut lp = orig_lp.clone();
         while let LpExtend(ref base_lp, mutbl, lp_elem) = lp.clone().kind {
             if let (&ty::Adt(adt_def, _), LpInterior(opt_variant_id, interior))
-                    = (&base_lp.ty.sty, lp_elem) {
+                    = (&base_lp.ty.kind, lp_elem) {
                 if adt_def.is_union() {
                     for (i, field) in adt_def.non_enum_variant().fields.iter().enumerate() {
                         let field =
@@ -361,7 +361,7 @@ impl MoveData<'tcx> {
     ) {
         // Assigning to one union field automatically assigns to all its fields.
         if let LpExtend(ref base_lp, mutbl, LpInterior(opt_variant_id, interior)) = lp.kind {
-            if let ty::Adt(adt_def, _) = base_lp.ty.sty {
+            if let ty::Adt(adt_def, _) = base_lp.ty.kind {
                 if adt_def.is_union() {
                     for (i, field) in adt_def.non_enum_variant().fields.iter().enumerate() {
                         let field =
diff --git a/src/librustc_codegen_llvm/builder.rs b/src/librustc_codegen_llvm/builder.rs
index 423a01ad1f937..b8b0e77d09830 100644
--- a/src/librustc_codegen_llvm/builder.rs
+++ b/src/librustc_codegen_llvm/builder.rs
@@ -324,7 +324,7 @@ impl BuilderMethods<'a, 'tcx> for Builder<'a, 'll, 'tcx> {
         use syntax::ast::UintTy::*;
         use rustc::ty::{Int, Uint};
 
-        let new_sty = match ty.sty {
+        let new_sty = match ty.kind {
             Int(Isize) => Int(self.tcx.sess.target.isize_ty),
             Uint(Usize) => Uint(self.tcx.sess.target.usize_ty),
             ref t @ Uint(_) | ref t @ Int(_) => t.clone(),
diff --git a/src/librustc_codegen_llvm/consts.rs b/src/librustc_codegen_llvm/consts.rs
index e71d1fc16924b..4fd971ca1153d 100644
--- a/src/librustc_codegen_llvm/consts.rs
+++ b/src/librustc_codegen_llvm/consts.rs
@@ -134,7 +134,7 @@ fn check_and_apply_linkage(
         // extern "C" fn() from being non-null, so we can't just declare a
         // static and call it a day. Some linkages (like weak) will make it such
         // that the static actually has a null value.
-        let llty2 = if let ty::RawPtr(ref mt) = ty.sty {
+        let llty2 = if let ty::RawPtr(ref mt) = ty.kind {
             cx.layout_of(mt.ty).llvm_type(cx)
         } else {
             cx.sess().span_fatal(
diff --git a/src/librustc_codegen_llvm/debuginfo/metadata.rs b/src/librustc_codegen_llvm/debuginfo/metadata.rs
index d0b607bd88ee4..02d68f47c7e7d 100644
--- a/src/librustc_codegen_llvm/debuginfo/metadata.rs
+++ b/src/librustc_codegen_llvm/debuginfo/metadata.rs
@@ -340,7 +340,7 @@ fn fixed_vec_metadata(
 
     let (size, align) = cx.size_and_align_of(array_or_slice_type);
 
-    let upper_bound = match array_or_slice_type.sty {
+    let upper_bound = match array_or_slice_type.kind {
         ty::Array(_, len) => len.eval_usize(cx.tcx, ty::ParamEnv::reveal_all()) as c_longlong,
         _ => -1
     };
@@ -427,7 +427,7 @@ fn subroutine_type_metadata(
 
     let signature_metadata: Vec<_> = iter::once(
         // return type
-        match signature.output().sty {
+        match signature.output().kind {
             ty::Tuple(ref tys) if tys.is_empty() => None,
             _ => Some(type_metadata(cx, signature.output(), span))
         }
@@ -466,7 +466,7 @@ fn trait_pointer_metadata(
     // type is assigned the correct name, size, namespace, and source location.
     // However, it does not describe the trait's methods.
 
-    let containing_scope = match trait_type.sty {
+    let containing_scope = match trait_type.kind {
         ty::Dynamic(ref data, ..) =>
             data.principal_def_id().map(|did| get_namespace_for_item(cx, did)),
         _ => {
@@ -563,7 +563,7 @@ pub fn type_metadata(
     debug!("type_metadata: {:?}", t);
 
     let ptr_metadata = |ty: Ty<'tcx>| {
-        match ty.sty {
+        match ty.kind {
             ty::Slice(typ) => {
                 Ok(vec_slice_metadata(cx, t, typ, unique_type_id, usage_site_span))
             }
@@ -591,7 +591,7 @@ pub fn type_metadata(
         }
     };
 
-    let MetadataCreationResult { metadata, already_stored_in_typemap } = match t.sty {
+    let MetadataCreationResult { metadata, already_stored_in_typemap } = match t.kind {
         ty::Never    |
         ty::Bool     |
         ty::Char     |
@@ -835,7 +835,7 @@ fn file_metadata_raw(cx: &CodegenCx<'ll, '_>,
 fn basic_type_metadata(cx: &CodegenCx<'ll, 'tcx>, t: Ty<'tcx>) -> &'ll DIType {
     debug!("basic_type_metadata: {:?}", t);
 
-    let (name, encoding) = match t.sty {
+    let (name, encoding) = match t.kind {
         ty::Never => ("!", DW_ATE_unsigned),
         ty::Tuple(ref elements) if elements.is_empty() =>
             ("()", DW_ATE_unsigned),
@@ -1145,7 +1145,7 @@ fn prepare_struct_metadata(
 ) -> RecursiveTypeDescription<'ll, 'tcx> {
     let struct_name = compute_debuginfo_type_name(cx.tcx, struct_type, false);
 
-    let (struct_def_id, variant) = match struct_type.sty {
+    let (struct_def_id, variant) = match struct_type.kind {
         ty::Adt(def, _) => (def.did, def.non_enum_variant()),
         _ => bug!("prepare_struct_metadata on a non-ADT")
     };
@@ -1268,7 +1268,7 @@ fn prepare_union_metadata(
 ) -> RecursiveTypeDescription<'ll, 'tcx> {
     let union_name = compute_debuginfo_type_name(cx.tcx, union_type, false);
 
-    let (union_def_id, variant) = match union_type.sty {
+    let (union_def_id, variant) = match union_type.kind {
         ty::Adt(def, _) => (def.did, def.non_enum_variant()),
         _ => bug!("prepare_union_metadata on a non-ADT")
     };
@@ -1334,7 +1334,7 @@ impl EnumMemberDescriptionFactory<'ll, 'tcx> {
     fn create_member_descriptions(&self, cx: &CodegenCx<'ll, 'tcx>)
                                   -> Vec<MemberDescription<'ll>> {
         let variant_info_for = |index: VariantIdx| {
-            match &self.enum_type.sty {
+            match &self.enum_type.kind {
                 ty::Adt(adt, _) => VariantInfo::Adt(&adt.variants[index]),
                 ty::Generator(def_id, substs, _) => {
                     let generator_layout = cx.tcx.generator_layout(*def_id);
@@ -1354,7 +1354,7 @@ impl EnumMemberDescriptionFactory<'ll, 'tcx> {
 
         match self.layout.variants {
             layout::Variants::Single { index } => {
-                if let ty::Adt(adt, _) = &self.enum_type.sty {
+                if let ty::Adt(adt, _) = &self.enum_type.kind {
                     if adt.variants.is_empty() {
                         return vec![];
                     }
@@ -1747,7 +1747,7 @@ fn prepare_enum_metadata(
     let file_metadata = unknown_file_metadata(cx);
 
     let discriminant_type_metadata = |discr: layout::Primitive| {
-        let enumerators_metadata: Vec<_> = match enum_type.sty {
+        let enumerators_metadata: Vec<_> = match enum_type.kind {
             ty::Adt(def, _) => def
                 .discriminants(cx.tcx)
                 .zip(&def.variants)
@@ -1790,7 +1790,7 @@ fn prepare_enum_metadata(
                 let discriminant_base_type_metadata =
                     type_metadata(cx, discr.to_ty(cx.tcx), syntax_pos::DUMMY_SP);
 
-                let discriminant_name = match enum_type.sty {
+                let discriminant_name = match enum_type.kind {
                     ty::Adt(..) => SmallCStr::new(&cx.tcx.item_name(enum_def_id).as_str()),
                     ty::Generator(..) => SmallCStr::new(&enum_name),
                     _ => bug!(),
@@ -1881,7 +1881,7 @@ fn prepare_enum_metadata(
         );
     }
 
-    let discriminator_name = match &enum_type.sty {
+    let discriminator_name = match &enum_type.kind {
         ty::Generator(..) => Some(SmallCStr::new(&"__state")),
         _ => None,
     };
@@ -2091,7 +2091,7 @@ fn set_members_of_composite_type(cx: &CodegenCx<'ll, 'tcx>,
 // Compute the type parameters for a type, if any, for the given
 // metadata.
 fn compute_type_parameters(cx: &CodegenCx<'ll, 'tcx>, ty: Ty<'tcx>) -> Option<&'ll DIArray> {
-    if let ty::Adt(def, substs) = ty.sty {
+    if let ty::Adt(def, substs) = ty.kind {
         if !substs.types().next().is_none() {
             let generics = cx.tcx.generics_of(def.did);
             let names = get_parameter_names(cx, generics);
diff --git a/src/librustc_codegen_llvm/debuginfo/mod.rs b/src/librustc_codegen_llvm/debuginfo/mod.rs
index 6dedf10f0ab83..08a37ce9bbfc8 100644
--- a/src/librustc_codegen_llvm/debuginfo/mod.rs
+++ b/src/librustc_codegen_llvm/debuginfo/mod.rs
@@ -377,7 +377,7 @@ impl DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
             let mut signature = Vec::with_capacity(sig.inputs().len() + 1);
 
             // Return type -- llvm::DIBuilder wants this at index 0
-            signature.push(match sig.output().sty {
+            signature.push(match sig.output().kind {
                 ty::Tuple(ref tys) if tys.is_empty() => None,
                 _ => Some(type_metadata(cx, sig.output(), syntax_pos::DUMMY_SP))
             });
@@ -401,7 +401,7 @@ impl DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
                 // This transformed type is wrong, but these function types are
                 // already inaccurate due to ABI adjustments (see #42800).
                 signature.extend(inputs.iter().map(|&t| {
-                    let t = match t.sty {
+                    let t = match t.kind {
                         ty::Array(ct, _)
                             if (ct == cx.tcx.types.u8) || cx.layout_of(ct).is_zst() => {
                             cx.tcx.mk_imm_ptr(ct)
@@ -417,7 +417,7 @@ impl DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
             }
 
             if sig.abi == Abi::RustCall && !sig.inputs().is_empty() {
-                if let ty::Tuple(args) = sig.inputs()[sig.inputs().len() - 1].sty {
+                if let ty::Tuple(args) = sig.inputs()[sig.inputs().len() - 1].kind {
                     signature.extend(
                         args.iter().map(|argument_type| {
                             Some(type_metadata(cx, argument_type.expect_ty(), syntax_pos::DUMMY_SP))
@@ -516,7 +516,7 @@ impl DebugInfoMethods<'tcx> for CodegenCx<'ll, 'tcx> {
 
                     // Only "class" methods are generally understood by LLVM,
                     // so avoid methods on other types (e.g., `<*mut T>::null`).
-                    match impl_self_ty.sty {
+                    match impl_self_ty.kind {
                         ty::Adt(def, ..) if !def.is_box() => {
                             Some(type_metadata(cx, impl_self_ty, syntax_pos::DUMMY_SP))
                         }
diff --git a/src/librustc_codegen_llvm/intrinsic.rs b/src/librustc_codegen_llvm/intrinsic.rs
index 3f3c5ac1460a3..b7a410c3760cd 100644
--- a/src/librustc_codegen_llvm/intrinsic.rs
+++ b/src/librustc_codegen_llvm/intrinsic.rs
@@ -91,7 +91,7 @@ impl IntrinsicCallMethods<'tcx> for Builder<'a, 'll, 'tcx> {
         let tcx = self.tcx;
         let callee_ty = instance.ty(tcx);
 
-        let (def_id, substs) = match callee_ty.sty {
+        let (def_id, substs) = match callee_ty.kind {
             ty::FnDef(def_id, substs) => (def_id, substs),
             _ => bug!("expected fn item type, found {}", callee_ty)
         };
@@ -1074,7 +1074,7 @@ fn generic_simd_intrinsic(
 
     if name == "simd_select_bitmask" {
         let in_ty = arg_tys[0];
-        let m_len = match in_ty.sty {
+        let m_len = match in_ty.kind {
             // Note that this `.unwrap()` crashes for isize/usize, that's sort
             // of intentional as there's not currently a use case for that.
             ty::Int(i) => i.bit_width().unwrap(),
@@ -1203,7 +1203,7 @@ fn generic_simd_intrinsic(
                  "mismatched lengths: mask length `{}` != other vector length `{}`",
                  m_len, v_len
         );
-        match m_elem_ty.sty {
+        match m_elem_ty.kind {
             ty::Int(_) => {},
             _ => return_error!("mask element type is `{}`, expected `i_`", m_elem_ty)
         }
@@ -1223,7 +1223,7 @@ fn generic_simd_intrinsic(
         // If the vector has less than 8 lanes, an u8 is returned with zeroed
         // trailing bits.
         let expected_int_bits = in_len.max(8);
-        match ret_ty.sty {
+        match ret_ty.kind {
            ty::Uint(i) if i.bit_width() == Some(expected_int_bits) => (),
             _ => return_error!(
                 "bitmask `{}`, expected `u{}`",
@@ -1232,7 +1232,7 @@ fn generic_simd_intrinsic(
         }
 
         // Integer vector <i{in_bitwidth} x in_len>:
-        let (i_xn, in_elem_bitwidth) = match in_elem.sty {
+        let (i_xn, in_elem_bitwidth) = match in_elem.kind {
             ty::Int(i) => (
                 args[0].immediate(),
                 i.bit_width().unwrap_or(bx.data_layout().pointer_size.bits() as _)
@@ -1288,7 +1288,7 @@ fn generic_simd_intrinsic(
                 }
             }
         }
-        let ety = match in_elem.sty {
+        let ety = match in_elem.kind {
             ty::Float(f) if f.bit_width() == 32 => {
                 if in_len < 2 || in_len > 16 {
                     return_error!(
@@ -1375,7 +1375,7 @@ fn generic_simd_intrinsic(
     //  https://github.com/llvm-mirror/llvm/blob/master/include/llvm/IR/Intrinsics.h#L81
     fn llvm_vector_str(elem_ty: Ty<'_>, vec_len: usize, no_pointers: usize) -> String {
         let p0s: String = "p0".repeat(no_pointers);
-        match elem_ty.sty {
+        match elem_ty.kind {
             ty::Int(v) => format!("v{}{}i{}", vec_len, p0s, v.bit_width().unwrap()),
             ty::Uint(v) => format!("v{}{}i{}", vec_len, p0s, v.bit_width().unwrap()),
             ty::Float(v) => format!("v{}{}f{}", vec_len, p0s, v.bit_width()),
@@ -1386,7 +1386,7 @@ fn generic_simd_intrinsic(
     fn llvm_vector_ty(cx: &CodegenCx<'ll, '_>, elem_ty: Ty<'_>, vec_len: usize,
                       mut no_pointers: usize) -> &'ll Type {
         // FIXME: use cx.layout_of(ty).llvm_type() ?
-        let mut elem_ty = match elem_ty.sty {
+        let mut elem_ty = match elem_ty.kind {
             ty::Int(v) => cx.type_int_from_ty( v),
             ty::Uint(v) => cx.type_uint_from_ty( v),
             ty::Float(v) => cx.type_float_from_ty( v),
@@ -1430,7 +1430,7 @@ fn generic_simd_intrinsic(
 
         // This counts how many pointers
         fn ptr_count(t: Ty<'_>) -> usize {
-            match t.sty {
+            match t.kind {
                 ty::RawPtr(p) => 1 + ptr_count(p.ty),
                 _ => 0,
             }
@@ -1438,7 +1438,7 @@ fn generic_simd_intrinsic(
 
         // Non-ptr type
         fn non_ptr(t: Ty<'_>) -> Ty<'_> {
-            match t.sty {
+            match t.kind {
                 ty::RawPtr(p) => non_ptr(p.ty),
                 _ => t,
             }
@@ -1446,7 +1446,7 @@ fn generic_simd_intrinsic(
 
         // The second argument must be a simd vector with an element type that's a pointer
         // to the element type of the first argument
-        let (pointer_count, underlying_ty) = match arg_tys[1].simd_type(tcx).sty {
+        let (pointer_count, underlying_ty) = match arg_tys[1].simd_type(tcx).kind {
             ty::RawPtr(p) if p.ty == in_elem => (ptr_count(arg_tys[1].simd_type(tcx)),
                                                  non_ptr(arg_tys[1].simd_type(tcx))),
             _ => {
@@ -1463,7 +1463,7 @@ fn generic_simd_intrinsic(
         assert_eq!(underlying_ty, non_ptr(arg_tys[0].simd_type(tcx)));
 
         // The element type of the third argument must be a signed integer type of any width:
-        match arg_tys[2].simd_type(tcx).sty {
+        match arg_tys[2].simd_type(tcx).kind {
             ty::Int(_) => (),
             _ => {
                 require!(false, "expected element type `{}` of third argument `{}` \
@@ -1529,7 +1529,7 @@ fn generic_simd_intrinsic(
 
         // This counts how many pointers
         fn ptr_count(t: Ty<'_>) -> usize {
-            match t.sty {
+            match t.kind {
                 ty::RawPtr(p) => 1 + ptr_count(p.ty),
                 _ => 0,
             }
@@ -1537,7 +1537,7 @@ fn generic_simd_intrinsic(
 
         // Non-ptr type
         fn non_ptr(t: Ty<'_>) -> Ty<'_> {
-            match t.sty {
+            match t.kind {
                 ty::RawPtr(p) => non_ptr(p.ty),
                 _ => t,
             }
@@ -1545,7 +1545,7 @@ fn generic_simd_intrinsic(
 
         // The second argument must be a simd vector with an element type that's a pointer
         // to the element type of the first argument
-        let (pointer_count, underlying_ty) = match arg_tys[1].simd_type(tcx).sty {
+        let (pointer_count, underlying_ty) = match arg_tys[1].simd_type(tcx).kind {
             ty::RawPtr(p) if p.ty == in_elem && p.mutbl == hir::MutMutable
                 => (ptr_count(arg_tys[1].simd_type(tcx)),
                     non_ptr(arg_tys[1].simd_type(tcx))),
@@ -1563,7 +1563,7 @@ fn generic_simd_intrinsic(
         assert_eq!(underlying_ty, non_ptr(arg_tys[0].simd_type(tcx)));
 
         // The element type of the third argument must be a signed integer type of any width:
-        match arg_tys[2].simd_type(tcx).sty {
+        match arg_tys[2].simd_type(tcx).kind {
             ty::Int(_) => (),
             _ => {
                 require!(false, "expected element type `{}` of third argument `{}` \
@@ -1612,7 +1612,7 @@ fn generic_simd_intrinsic(
                 require!(ret_ty == in_elem,
                          "expected return type `{}` (element of input `{}`), found `{}`",
                          in_elem, in_ty, ret_ty);
-                return match in_elem.sty {
+                return match in_elem.kind {
                     ty::Int(_) | ty::Uint(_) => {
                         let r = bx.$integer_reduce(args[0].immediate());
                         if $ordered {
@@ -1669,7 +1669,7 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
                 require!(ret_ty == in_elem,
                          "expected return type `{}` (element of input `{}`), found `{}`",
                          in_elem, in_ty, ret_ty);
-                return match in_elem.sty {
+                return match in_elem.kind {
                     ty::Int(_i) => {
                         Ok(bx.$int_red(args[0].immediate(), true))
                     },
@@ -1704,7 +1704,7 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
                              in_elem, in_ty, ret_ty);
                     args[0].immediate()
                 } else {
-                    match in_elem.sty {
+                    match in_elem.kind {
                         ty::Int(_) | ty::Uint(_) => {},
                         _ => {
                             return_error!("unsupported {} from `{}` with element `{}` to `{}`",
@@ -1717,7 +1717,7 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
                     let i1xn = bx.type_vector(i1, in_len as u64);
                     bx.trunc(args[0].immediate(), i1xn)
                 };
-                return match in_elem.sty {
+                return match in_elem.kind {
                     ty::Int(_) | ty::Uint(_) => {
                         let r = bx.$red(input);
                         Ok(
@@ -1758,7 +1758,7 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
 
         enum Style { Float, Int(/* is signed? */ bool), Unsupported }
 
-        let (in_style, in_width) = match in_elem.sty {
+        let (in_style, in_width) = match in_elem.kind {
             // vectors of pointer-sized integers should've been
             // disallowed before here, so this unwrap is safe.
             ty::Int(i) => (Style::Int(true), i.bit_width().unwrap()),
@@ -1766,7 +1766,7 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
             ty::Float(f) => (Style::Float, f.bit_width()),
             _ => (Style::Unsupported, 0)
         };
-        let (out_style, out_width) = match out_elem.sty {
+        let (out_style, out_width) = match out_elem.kind {
             ty::Int(i) => (Style::Int(true), i.bit_width().unwrap()),
             ty::Uint(u) => (Style::Int(false), u.bit_width().unwrap()),
             ty::Float(f) => (Style::Float, f.bit_width()),
@@ -1816,7 +1816,7 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
     macro_rules! arith {
         ($($name: ident: $($($p: ident),* => $call: ident),*;)*) => {
             $(if name == stringify!($name) {
-                match in_elem.sty {
+                match in_elem.kind {
                     $($(ty::$p(_))|* => {
                         return Ok(bx.$call(args[0].immediate(), args[1].immediate()))
                     })*
@@ -1850,7 +1850,7 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
         let rhs = args[1].immediate();
         let is_add = name == "simd_saturating_add";
         let ptr_bits = bx.tcx().data_layout.pointer_size.bits() as _;
-        let (signed, elem_width, elem_ty) = match in_elem.sty {
+        let (signed, elem_width, elem_ty) = match in_elem.kind {
             ty::Int(i) =>
                 (
                     true,
@@ -1896,7 +1896,7 @@ unsupported {} from `{}` with element `{}` of size `{}` to `{}`"#,
 // FIXME: there’s multiple of this functions, investigate using some of the already existing
 // stuffs.
 fn int_type_width_signed(ty: Ty<'_>, cx: &CodegenCx<'_, '_>) -> Option<(u64, bool)> {
-    match ty.sty {
+    match ty.kind {
         ty::Int(t) => Some((match t {
             ast::IntTy::Isize => cx.tcx.sess.target.isize_ty.bit_width().unwrap() as u64,
             ast::IntTy::I8 => 8,
@@ -1920,7 +1920,7 @@ fn int_type_width_signed(ty: Ty<'_>, cx: &CodegenCx<'_, '_>) -> Option<(u64, boo
 // Returns the width of a float Ty
 // Returns None if the type is not a float
 fn float_type_width(ty: Ty<'_>) -> Option<u64> {
-    match ty.sty {
+    match ty.kind {
         ty::Float(t) => Some(t.bit_width() as u64),
         _ => None,
     }
diff --git a/src/librustc_codegen_llvm/type_of.rs b/src/librustc_codegen_llvm/type_of.rs
index 36a9ff0a2d2e5..81a99bc5019b3 100644
--- a/src/librustc_codegen_llvm/type_of.rs
+++ b/src/librustc_codegen_llvm/type_of.rs
@@ -43,7 +43,7 @@ fn uncached_llvm_type<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
         layout::Abi::Aggregate { .. } => {}
     }
 
-    let name = match layout.ty.sty {
+    let name = match layout.ty.kind {
         ty::Closure(..) |
         ty::Generator(..) |
         ty::Adt(..) |
@@ -56,14 +56,14 @@ fn uncached_llvm_type<'a, 'tcx>(cx: &CodegenCx<'a, 'tcx>,
             let printer = DefPathBasedNames::new(cx.tcx, true, true);
             printer.push_type_name(layout.ty, &mut name, false);
             if let (&ty::Adt(def, _), &layout::Variants::Single { index })
-                 = (&layout.ty.sty, &layout.variants)
+                 = (&layout.ty.kind, &layout.variants)
             {
                 if def.is_enum() && !def.variants.is_empty() {
                     write!(&mut name, "::{}", def.variants[index].ident).unwrap();
                 }
             }
             if let (&ty::Generator(_, substs, _), &layout::Variants::Single { index })
-                 = (&layout.ty.sty, &layout.variants)
+                 = (&layout.ty.kind, &layout.variants)
             {
                 write!(&mut name, "::{}", substs.variant_name(index)).unwrap();
             }
@@ -226,7 +226,7 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyLayout<'tcx> {
             if let Some(&llty) = cx.scalar_lltypes.borrow().get(&self.ty) {
                 return llty;
             }
-            let llty = match self.ty.sty {
+            let llty = match self.ty.kind {
                 ty::Ref(_, ty, _) |
                 ty::RawPtr(ty::TypeAndMut { ty, .. }) => {
                     cx.type_ptr_to(cx.layout_of(ty).llvm_type(cx))
@@ -318,7 +318,7 @@ impl<'tcx> LayoutLlvmExt<'tcx> for TyLayout<'tcx> {
                                          index: usize, immediate: bool) -> &'a Type {
         // HACK(eddyb) special-case fat pointers until LLVM removes
         // pointee types, to avoid bitcasting every `OperandRef::deref`.
-        match self.ty.sty {
+        match self.ty.kind {
             ty::Ref(..) |
             ty::RawPtr(_) => {
                 return self.field(cx, index).llvm_type(cx);
diff --git a/src/librustc_codegen_ssa/base.rs b/src/librustc_codegen_ssa/base.rs
index 98d3022a4185d..8f7f769f6b996 100644
--- a/src/librustc_codegen_ssa/base.rs
+++ b/src/librustc_codegen_ssa/base.rs
@@ -96,7 +96,7 @@ pub fn compare_simd_types<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     ret_ty: Bx::Type,
     op: hir::BinOpKind,
 ) -> Bx::Value {
-    let signed = match t.sty {
+    let signed = match t.kind {
         ty::Float(_) => {
             let cmp = bin_op_to_fcmp_predicate(op);
             let cmp = bx.fcmp(cmp, lhs, rhs);
@@ -130,7 +130,7 @@ pub fn unsized_info<'tcx, Cx: CodegenMethods<'tcx>>(
 ) -> Cx::Value {
     let (source, target) =
         cx.tcx().struct_lockstep_tails_erasing_lifetimes(source, target, cx.param_env());
-    match (&source.sty, &target.sty) {
+    match (&source.kind, &target.kind) {
         (&ty::Array(_, len), &ty::Slice(_)) => {
             cx.const_usize(len.eval_usize(cx.tcx(), ty::ParamEnv::reveal_all()))
         }
@@ -160,7 +160,7 @@ pub fn unsize_thin_ptr<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
     dst_ty: Ty<'tcx>,
 ) -> (Bx::Value, Bx::Value) {
     debug!("unsize_thin_ptr: {:?} => {:?}", src_ty, dst_ty);
-    match (&src_ty.sty, &dst_ty.sty) {
+    match (&src_ty.kind, &dst_ty.kind) {
         (&ty::Ref(_, a, _),
          &ty::Ref(_, b, _)) |
         (&ty::Ref(_, a, _),
@@ -232,7 +232,7 @@ pub fn coerce_unsized_into<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
         };
         OperandValue::Pair(base, info).store(bx, dst);
     };
-    match (&src_ty.sty, &dst_ty.sty) {
+    match (&src_ty.kind, &dst_ty.kind) {
         (&ty::Ref(..), &ty::Ref(..)) |
         (&ty::Ref(..), &ty::RawPtr(..)) |
         (&ty::RawPtr(..), &ty::RawPtr(..)) => {
diff --git a/src/librustc_codegen_ssa/debuginfo/type_names.rs b/src/librustc_codegen_ssa/debuginfo/type_names.rs
index 9b5ad94ecd7cb..d875c60959cba 100644
--- a/src/librustc_codegen_ssa/debuginfo/type_names.rs
+++ b/src/librustc_codegen_ssa/debuginfo/type_names.rs
@@ -32,7 +32,7 @@ pub fn push_debuginfo_type_name<'tcx>(
     // .natvis visualizers (and perhaps other existing native debuggers?)
     let cpp_like_names = tcx.sess.target.target.options.is_like_msvc;
 
-    match t.sty {
+    match t.kind {
         ty::Bool => output.push_str("bool"),
         ty::Char => output.push_str("char"),
         ty::Str => output.push_str("str"),
diff --git a/src/librustc_codegen_ssa/glue.rs b/src/librustc_codegen_ssa/glue.rs
index 7fd9f67e2f45b..9818bb78e757b 100644
--- a/src/librustc_codegen_ssa/glue.rs
+++ b/src/librustc_codegen_ssa/glue.rs
@@ -20,7 +20,7 @@ pub fn size_and_align_of_dst<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
         let align = bx.const_usize(layout.align.abi.bytes());
         return (size, align);
     }
-    match t.sty {
+    match t.kind {
         ty::Dynamic(..) => {
             // load size/align from vtable
             let vtable = info.unwrap();
@@ -64,7 +64,7 @@ pub fn size_and_align_of_dst<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
             let size = bx.add(sized_size, unsized_size);
 
             // Packed types ignore the alignment of their fields.
-            if let ty::Adt(def, _) = t.sty {
+            if let ty::Adt(def, _) = t.kind {
                 if def.repr.packed() {
                     unsized_align = sized_align;
                 }
diff --git a/src/librustc_codegen_ssa/mir/analyze.rs b/src/librustc_codegen_ssa/mir/analyze.rs
index d192f2ffb6fba..05896523863c2 100644
--- a/src/librustc_codegen_ssa/mir/analyze.rs
+++ b/src/librustc_codegen_ssa/mir/analyze.rs
@@ -218,7 +218,7 @@ impl<'mir, 'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> Visitor<'tcx>
             mir::TerminatorKind::Call {
                 func: mir::Operand::Constant(ref c),
                 ref args, ..
-            } => match c.literal.ty.sty {
+            } => match c.literal.ty.kind {
                 ty::FnDef(did, _) => Some((did, args)),
                 _ => None,
             },
diff --git a/src/librustc_codegen_ssa/mir/block.rs b/src/librustc_codegen_ssa/mir/block.rs
index 1bb0ea5dae44b..3069199a21256 100644
--- a/src/librustc_codegen_ssa/mir/block.rs
+++ b/src/librustc_codegen_ssa/mir/block.rs
@@ -323,7 +323,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             args1 = [place.llval];
             &args1[..]
         };
-        let (drop_fn, fn_ty) = match ty.sty {
+        let (drop_fn, fn_ty) = match ty.kind {
             ty::Dynamic(..) => {
                 let sig = drop_fn.fn_sig(self.cx.tcx());
                 let sig = self.cx.tcx().normalize_erasing_late_bound_regions(
@@ -455,7 +455,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         // Create the callee. This is a fn ptr or zero-sized and hence a kind of scalar.
         let callee = self.codegen_operand(&mut bx, func);
 
-        let (instance, mut llfn) = match callee.layout.ty.sty {
+        let (instance, mut llfn) = match callee.layout.ty.kind {
             ty::FnDef(def_id, substs) => {
                 (Some(ty::Instance::resolve(bx.tcx(),
                                             ty::ParamEnv::reveal_all(),
diff --git a/src/librustc_codegen_ssa/mir/constant.rs b/src/librustc_codegen_ssa/mir/constant.rs
index 216e5a4645a46..9cfe410fcc5e0 100644
--- a/src/librustc_codegen_ssa/mir/constant.rs
+++ b/src/librustc_codegen_ssa/mir/constant.rs
@@ -40,7 +40,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
         constant
             .map(|c| {
                 let field_ty = c.ty.builtin_index().unwrap();
-                let fields = match c.ty.sty {
+                let fields = match c.ty.kind {
                     ty::Array(_, n) => n.eval_usize(bx.tcx(), ty::ParamEnv::reveal_all()),
                     _ => bug!("invalid simd shuffle type: {}", c.ty),
                 };
diff --git a/src/librustc_codegen_ssa/mir/mod.rs b/src/librustc_codegen_ssa/mir/mod.rs
index aa3971a1da81a..c341c0685c6a7 100644
--- a/src/librustc_codegen_ssa/mir/mod.rs
+++ b/src/librustc_codegen_ssa/mir/mod.rs
@@ -467,7 +467,7 @@ fn arg_local_refs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
             // individual LLVM function arguments.
 
             let arg_ty = fx.monomorphize(&arg_decl.ty);
-            let tupled_arg_tys = match arg_ty.sty {
+            let tupled_arg_tys = match arg_ty.kind {
                 ty::Tuple(ref tys) => tys,
                 _ => bug!("spread argument isn't a tuple?!")
             };
@@ -573,7 +573,7 @@ fn arg_local_refs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
                     Some(did) => did,
                     None => bug!("`va_list` lang item required for C-variadic functions"),
                 };
-                match arg_decl.ty.sty {
+                match arg_decl.ty.kind {
                     ty::Adt(def, _) if def.did == va_list_did => {
                         // Call `va_start` on the spoofed `VaListImpl`.
                         bx.va_start(tmp.llval);
@@ -612,11 +612,11 @@ fn arg_local_refs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
 
             let pin_did = tcx.lang_items().pin_type();
             // Or is it the closure environment?
-            let (closure_layout, env_ref) = match arg.layout.ty.sty {
+            let (closure_layout, env_ref) = match arg.layout.ty.kind {
                 ty::RawPtr(ty::TypeAndMut { ty, .. }) |
                 ty::Ref(_, ty, _)  => (bx.layout_of(ty), true),
                 ty::Adt(def, substs) if Some(def.did) == pin_did => {
-                    match substs.type_at(0).sty {
+                    match substs.type_at(0).kind {
                         ty::Ref(_, ty, _)  => (bx.layout_of(ty), true),
                         _ => (arg.layout, false),
                     }
@@ -624,7 +624,7 @@ fn arg_local_refs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
                 _ => (arg.layout, false)
             };
 
-            let (def_id, upvar_substs) = match closure_layout.ty.sty {
+            let (def_id, upvar_substs) = match closure_layout.ty.kind {
                 ty::Closure(def_id, substs) => (def_id, UpvarSubsts::Closure(substs)),
                 ty::Generator(def_id, substs, _) => (def_id, UpvarSubsts::Generator(substs)),
                 _ => bug!("upvar debuginfo with non-closure arg0 type `{}`", closure_layout.ty)
@@ -641,7 +641,7 @@ fn arg_local_refs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
                     });
 
                 let generator_fields = mir.generator_layout.as_ref().map(|generator_layout| {
-                    let (def_id, gen_substs) = match closure_layout.ty.sty {
+                    let (def_id, gen_substs) = match closure_layout.ty.kind {
                         ty::Generator(def_id, substs, _) => (def_id, substs),
                         _ => bug!("generator layout without generator substs"),
                     };
@@ -695,7 +695,7 @@ fn arg_local_refs<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>>(
                 // The environment and the capture can each be indirect.
                 let mut ops = if env_ref { &ops[..] } else { &ops[1..] };
 
-                let ty = if let (true, &ty::Ref(_, ty, _)) = (by_ref, &ty.sty) {
+                let ty = if let (true, &ty::Ref(_, ty, _)) = (by_ref, &ty.kind) {
                     ty
                 } else {
                     ops = &ops[..ops.len() - 1];
diff --git a/src/librustc_codegen_ssa/mir/place.rs b/src/librustc_codegen_ssa/mir/place.rs
index a4b4cb53bb1fb..2d97f828f073d 100644
--- a/src/librustc_codegen_ssa/mir/place.rs
+++ b/src/librustc_codegen_ssa/mir/place.rs
@@ -144,7 +144,7 @@ impl<'a, 'tcx, V: CodegenObject> PlaceRef<'tcx, V> {
         //   * no metadata available - just log the case
         //   * known alignment - sized types, `[T]`, `str` or a foreign type
         //   * packed struct - there is no alignment padding
-        match field.ty.sty {
+        match field.ty.kind {
             _ if self.llextra.is_none() => {
                 debug!("unsized field `{}`, of `{:?}` has no metadata for adjustment",
                     ix, self.llval);
diff --git a/src/librustc_codegen_ssa/mir/rvalue.rs b/src/librustc_codegen_ssa/mir/rvalue.rs
index f21836a953c22..9b69383b455cf 100644
--- a/src/librustc_codegen_ssa/mir/rvalue.rs
+++ b/src/librustc_codegen_ssa/mir/rvalue.rs
@@ -184,7 +184,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
 
                 let val = match *kind {
                     mir::CastKind::Pointer(PointerCast::ReifyFnPointer) => {
-                        match operand.layout.ty.sty {
+                        match operand.layout.ty.kind {
                             ty::FnDef(def_id, substs) => {
                                 if bx.cx().tcx().has_attr(def_id, sym::rustc_args_required_const) {
                                     bug!("reifying a fn ptr that requires const arguments");
@@ -198,7 +198,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
                         }
                     }
                     mir::CastKind::Pointer(PointerCast::ClosureFnPointer(_)) => {
-                        match operand.layout.ty.sty {
+                        match operand.layout.ty.kind {
                             ty::Closure(def_id, substs) => {
                                 let instance = Instance::resolve_closure(
                                     bx.cx().tcx(), def_id, substs, ty::ClosureKind::FnOnce);
@@ -525,7 +525,7 @@ impl<'a, 'tcx, Bx: BuilderMethods<'a, 'tcx>> FunctionCx<'a, 'tcx, Bx> {
             projection: box [],
         } = *place {
             if let LocalRef::Operand(Some(op)) = self.locals[index] {
-                if let ty::Array(_, n) = op.layout.ty.sty {
+                if let ty::Array(_, n) = op.layout.ty.kind {
                     let n = n.eval_usize(bx.cx().tcx(), ty::ParamEnv::reveal_all());
                     return bx.cx().const_usize(n);
                 }
diff --git a/src/librustc_codegen_ssa/traits/type_.rs b/src/librustc_codegen_ssa/traits/type_.rs
index 13f72e23819a1..19d41c6b37cbb 100644
--- a/src/librustc_codegen_ssa/traits/type_.rs
+++ b/src/librustc_codegen_ssa/traits/type_.rs
@@ -83,7 +83,7 @@ pub trait DerivedTypeMethods<'tcx>: BaseTypeMethods<'tcx> + MiscMethods<'tcx> {
         }
 
         let tail = self.tcx().struct_tail_erasing_lifetimes(ty, param_env);
-        match tail.sty {
+        match tail.kind {
             ty::Foreign(..) => false,
             ty::Str | ty::Slice(..) | ty::Dynamic(..) => true,
             _ => bug!("unexpected unsized tail: {:?}", tail),
diff --git a/src/librustc_codegen_utils/symbol_names/legacy.rs b/src/librustc_codegen_utils/symbol_names/legacy.rs
index 22b7e0a2fb0c9..1b094e26c2443 100644
--- a/src/librustc_codegen_utils/symbol_names/legacy.rs
+++ b/src/librustc_codegen_utils/symbol_names/legacy.rs
@@ -111,7 +111,7 @@ fn get_symbol_hash<'tcx>(
         // If this is a function, we hash the signature as well.
         // This is not *strictly* needed, but it may help in some
         // situations, see the `run-make/a-b-a-linker-guard` test.
-        if let ty::FnDef(..) = item_type.sty {
+        if let ty::FnDef(..) = item_type.kind {
             item_type.fn_sig(tcx).hash_stable(&mut hcx, &mut hasher);
         }
 
@@ -218,7 +218,7 @@ impl Printer<'tcx> for SymbolPrinter<'tcx> {
         self,
         ty: Ty<'tcx>,
     ) -> Result<Self::Type, Self::Error> {
-        match ty.sty {
+        match ty.kind {
             // Print all nominal types as paths (unlike `pretty_print_type`).
             ty::FnDef(def_id, substs) |
             ty::Opaque(def_id, substs) |
@@ -275,7 +275,7 @@ impl Printer<'tcx> for SymbolPrinter<'tcx> {
     ) -> Result<Self::Path, Self::Error> {
         // Similar to `pretty_path_qualified`, but for the other
         // types that are printed as paths (see `print_type` above).
-        match self_ty.sty {
+        match self_ty.kind {
             ty::FnDef(..) |
             ty::Opaque(..) |
             ty::Projection(_) |
diff --git a/src/librustc_codegen_utils/symbol_names/v0.rs b/src/librustc_codegen_utils/symbol_names/v0.rs
index 8d6a1d757e014..f1f5913425d01 100644
--- a/src/librustc_codegen_utils/symbol_names/v0.rs
+++ b/src/librustc_codegen_utils/symbol_names/v0.rs
@@ -323,7 +323,7 @@ impl Printer<'tcx> for SymbolMangler<'tcx> {
         ty: Ty<'tcx>,
     ) -> Result<Self::Type, Self::Error> {
         // Basic types, never cached (single-character).
-        let basic_type = match ty.sty {
+        let basic_type = match ty.kind {
             ty::Bool => "b",
             ty::Char => "c",
             ty::Str => "e",
@@ -360,7 +360,7 @@ impl Printer<'tcx> for SymbolMangler<'tcx> {
         }
         let start = self.out.len();
 
-        match ty.sty {
+        match ty.kind {
             // Basic types, handled above.
             ty::Bool | ty::Char | ty::Str |
             ty::Int(_) | ty::Uint(_) | ty::Float(_) |
@@ -511,7 +511,7 @@ impl Printer<'tcx> for SymbolMangler<'tcx> {
         }
         let start = self.out.len();
 
-        match ct.ty.sty {
+        match ct.ty.kind {
             ty::Uint(_) => {}
             _ => {
                 bug!("symbol_names: unsupported constant of type `{}` ({:?})",
diff --git a/src/librustc_lint/builtin.rs b/src/librustc_lint/builtin.rs
index cf19a9eb147a8..d08fd47dc169e 100644
--- a/src/librustc_lint/builtin.rs
+++ b/src/librustc_lint/builtin.rs
@@ -918,7 +918,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for MutableTransmutes {
 
         let msg = "mutating transmuted &mut T from &T may cause undefined behavior, \
                    consider instead using an UnsafeCell";
-        match get_transmute_from_to(cx, expr).map(|(ty1, ty2)| (&ty1.sty, &ty2.sty)) {
+        match get_transmute_from_to(cx, expr).map(|(ty1, ty2)| (&ty1.kind, &ty2.kind)) {
             Some((&ty::Ref(_, _, from_mt), &ty::Ref(_, _, to_mt))) => {
                 if to_mt == hir::Mutability::MutMutable &&
                    from_mt == hir::Mutability::MutImmutable {
@@ -1954,7 +1954,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for InvalidValue {
             init: InitKind,
         ) -> Option<InitError> {
             use rustc::ty::TyKind::*;
-            match ty.sty {
+            match ty.kind {
                 // Primitive types that don't like 0 as a value.
                 Ref(..) => Some((format!("References must be non-null"), None)),
                 Adt(..) if ty.is_box() => Some((format!("`Box` must be non-null"), None)),
diff --git a/src/librustc_lint/types.rs b/src/librustc_lint/types.rs
index 40261f6d13739..3a037b4dfff1f 100644
--- a/src/librustc_lint/types.rs
+++ b/src/librustc_lint/types.rs
@@ -227,7 +227,7 @@ fn get_type_suggestion(t: Ty<'_>, val: u128, negative: bool) -> Option<String> {
             }
         }
     }
-    match t.sty {
+    match t.kind {
         ty::Int(i) => find_fit!(i, val, negative,
                       I8 => [U8] => [I16, I32, I64, I128],
                       I16 => [U16] => [I32, I64, I128],
@@ -320,7 +320,7 @@ fn lint_uint_literal<'a, 'tcx>(
         if let Node::Expr(par_e) = cx.tcx.hir().get(parent_id) {
             match par_e.node {
                 hir::ExprKind::Cast(..) => {
-                    if let ty::Char = cx.tables.expr_ty(par_e).sty {
+                    if let ty::Char = cx.tables.expr_ty(par_e).kind {
                         let mut err = cx.struct_span_lint(
                             OVERFLOWING_LITERALS,
                             par_e.span,
@@ -364,7 +364,7 @@ fn lint_literal<'a, 'tcx>(
     e: &'tcx hir::Expr,
     lit: &hir::Lit,
 ) {
-    match cx.tables.node_type(e.hir_id).sty {
+    match cx.tables.node_type(e.hir_id).kind {
         ty::Int(t) => {
             match lit.node {
                 ast::LitKind::Int(v, ast::LitIntType::Signed(_)) |
@@ -453,7 +453,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for TypeLimits {
             // Normalize the binop so that the literal is always on the RHS in
             // the comparison
             let norm_binop = if swap { rev_binop(binop) } else { binop };
-            match cx.tables.node_type(expr.hir_id).sty {
+            match cx.tables.node_type(expr.hir_id).kind {
                 ty::Int(int_ty) => {
                     let (min, max) = int_ty_range(int_ty);
                     let lit_val: i128 = match lit.node {
@@ -526,7 +526,7 @@ fn is_zst<'tcx>(tcx: TyCtxt<'tcx>, did: DefId, ty: Ty<'tcx>) -> bool {
 }
 
 fn ty_is_known_nonnull<'tcx>(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> bool {
-    match ty.sty {
+    match ty.kind {
         ty::FnPtr(_) => true,
         ty::Ref(..) => true,
         ty::Adt(field_def, substs) if field_def.repr.transparent() && !field_def.is_union() => {
@@ -615,7 +615,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
             return FfiSafe;
         }
 
-        match ty.sty {
+        match ty.kind {
             ty::Adt(def, substs) => {
                 if def.is_phantom_data() {
                     return FfiPhantom(ty);
@@ -876,7 +876,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
             diag.help(help);
         }
         diag.note(note);
-        if let ty::Adt(def, _) = ty.sty {
+        if let ty::Adt(def, _) = ty.kind {
             if let Some(sp) = self.cx.tcx.hir().span_if_local(def.did) {
                 diag.span_note(sp, "type defined here");
             }
@@ -893,7 +893,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
 
         impl<'tcx> ty::fold::TypeVisitor<'tcx> for ProhibitOpaqueTypes<'tcx> {
             fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
-                if let ty::Opaque(..) = ty.sty {
+                if let ty::Opaque(..) = ty.kind {
                     self.ty = Some(ty);
                     true
                 } else {
diff --git a/src/librustc_lint/unused.rs b/src/librustc_lint/unused.rs
index 2d4af2f606a2c..86df0b9f681e4 100644
--- a/src/librustc_lint/unused.rs
+++ b/src/librustc_lint/unused.rs
@@ -145,7 +145,7 @@ impl<'a, 'tcx> LateLintPass<'a, 'tcx> for UnusedResults {
 
             let plural_suffix = pluralise!(plural_len);
 
-            match ty.sty {
+            match ty.kind {
                 ty::Adt(..) if ty.is_box() => {
                     let boxed_ty = ty.boxed_ty();
                     let descr_pre = &format!("{}boxed ", descr_pre);
diff --git a/src/librustc_metadata/decoder.rs b/src/librustc_metadata/decoder.rs
index 247748eb3eba5..3c6a1c4744696 100644
--- a/src/librustc_metadata/decoder.rs
+++ b/src/librustc_metadata/decoder.rs
@@ -722,7 +722,7 @@ impl<'a, 'tcx> CrateMetadata {
         self.get_impl_data(id).parent_impl
     }
 
-    pub fn get_impl_polarity(&self, id: DefIndex) -> hir::ImplPolarity {
+    pub fn get_impl_polarity(&self, id: DefIndex) -> ty::ImplPolarity {
         self.get_impl_data(id).polarity
     }
 
diff --git a/src/librustc_metadata/encoder.rs b/src/librustc_metadata/encoder.rs
index 965a8658c9592..8a68581ff8b14 100644
--- a/src/librustc_metadata/encoder.rs
+++ b/src/librustc_metadata/encoder.rs
@@ -1175,8 +1175,9 @@ impl EncodeContext<'tcx> {
                     ctor_sig: None,
                 }), repr_options)
             }
-            hir::ItemKind::Impl(_, polarity, defaultness, ..) => {
+            hir::ItemKind::Impl(_, _, defaultness, ..) => {
                 let trait_ref = tcx.impl_trait_ref(def_id);
+                let polarity = tcx.impl_polarity(def_id);
                 let parent = if let Some(trait_ref) = trait_ref {
                     let trait_def = tcx.trait_def(trait_ref.def_id);
                     trait_def.ancestors(tcx, def_id).nth(1).and_then(|node| {
@@ -1427,7 +1428,7 @@ impl EncodeContext<'tcx> {
 
         let tables = self.tcx.typeck_tables_of(def_id);
         let hir_id = self.tcx.hir().as_local_hir_id(def_id).unwrap();
-        let kind = match tables.node_type(hir_id).sty {
+        let kind = match tables.node_type(hir_id).kind {
             ty::Generator(def_id, ..) => {
                 let layout = self.tcx.generator_layout(def_id);
                 let data = GeneratorData {
@@ -1978,7 +1979,7 @@ pub fn encode_metadata(tcx: TyCtxt<'_>) -> EncodedMetadata {
 
 pub fn get_repr_options(tcx: TyCtxt<'_>, did: DefId) -> ReprOptions {
     let ty = tcx.type_of(did);
-    match ty.sty {
+    match ty.kind {
         ty::Adt(ref def, _) => return def.repr,
         _ => bug!("{} is not an ADT", ty),
     }
diff --git a/src/librustc_metadata/schema.rs b/src/librustc_metadata/schema.rs
index 92534ab056a8b..4be70c6203569 100644
--- a/src/librustc_metadata/schema.rs
+++ b/src/librustc_metadata/schema.rs
@@ -328,7 +328,7 @@ pub struct TraitAliasData<'tcx> {
 
 #[derive(RustcEncodable, RustcDecodable)]
 pub struct ImplData<'tcx> {
-    pub polarity: hir::ImplPolarity,
+    pub polarity: ty::ImplPolarity,
     pub defaultness: hir::Defaultness,
     pub parent_impl: Option<DefId>,
 
diff --git a/src/librustc_mir/borrow_check/conflict_errors.rs b/src/librustc_mir/borrow_check/conflict_errors.rs
index 599a0ad0d0c52..87b99ee47641b 100644
--- a/src/librustc_mir/borrow_check/conflict_errors.rs
+++ b/src/librustc_mir/borrow_check/conflict_errors.rs
@@ -105,9 +105,6 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 format!("{} occurs due to use{}", desired_action.as_noun(), use_spans.describe()),
             );
 
-            // This error should not be downgraded to a warning,
-            // even in migrate mode.
-            self.disable_error_downgrading();
             err.buffer(&mut self.errors_buffer);
         } else {
             if let Some((reported_place, _)) = self.move_error_reported.get(&move_out_indices) {
@@ -211,7 +208,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             let ty =
                 Place::ty_from(used_place.base, used_place.projection, self.body, self.infcx.tcx)
                     .ty;
-            let needs_note = match ty.sty {
+            let needs_note = match ty.kind {
                 ty::Closure(id, _) => {
                     let tables = self.infcx.tcx.typeck_tables_of(id);
                     let hir_id = self.infcx.tcx.hir().as_local_hir_id(id).unwrap();
@@ -232,7 +229,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     Some(ref name) => format!("`{}`", name),
                     None => "value".to_owned(),
                 };
-                if let ty::Param(param_ty) = ty.sty {
+                if let ty::Param(param_ty) = ty.kind {
                     let tcx = self.infcx.tcx;
                     let generics = tcx.generics_of(self.mir_def_id);
                     let def_id = generics.type_param(&param_ty, tcx).def_id;
@@ -1243,7 +1240,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let escapes_from = if tcx.is_closure(self.mir_def_id) {
             let tables = tcx.typeck_tables_of(self.mir_def_id);
             let mir_hir_id = tcx.hir().def_index_to_hir_id(self.mir_def_id.index);
-            match tables.node_type(mir_hir_id).sty {
+            match tables.node_type(mir_hir_id).kind {
                 ty::Closure(..) => "closure",
                 ty::Generator(..) => "generator",
                 _ => bug!("Closure body doesn't have a closure or generator type"),
@@ -1543,7 +1540,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     },
                     ProjectionElem::Field(..) | ProjectionElem::Downcast(..) => {
                         let base_ty = Place::ty_from(&place.base, proj_base, self.body, tcx).ty;
-                        match base_ty.sty {
+                        match base_ty.kind {
                             ty::Adt(def, _) if def.has_dtor(tcx) => {
                                 // Report the outermost adt with a destructor
                                 match base_access {
@@ -1579,7 +1576,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 None
             } else {
                 let ty = self.infcx.tcx.type_of(self.mir_def_id);
-                match ty.sty {
+                match ty.kind {
                     ty::FnDef(_, _) | ty::FnPtr(_) => self.annotate_fn_sig(
                         self.mir_def_id,
                         self.infcx.tcx.fn_sig(self.mir_def_id),
@@ -1834,13 +1831,13 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         // 3. The return type is not a reference. In this case, we don't highlight
         //    anything.
         let return_ty = sig.output();
-        match return_ty.skip_binder().sty {
+        match return_ty.skip_binder().kind {
             ty::Ref(return_region, _, _) if return_region.has_name() && !is_closure => {
                 // This is case 1 from above, return type is a named reference so we need to
                 // search for relevant arguments.
                 let mut arguments = Vec::new();
                 for (index, argument) in sig.inputs().skip_binder().iter().enumerate() {
-                    if let ty::Ref(argument_region, _, _) = argument.sty {
+                    if let ty::Ref(argument_region, _, _) = argument.kind {
                         if argument_region == return_region {
                             // Need to use the `rustc::ty` types to compare against the
                             // `return_region`. Then use the `rustc::hir` type to get only
@@ -1886,9 +1883,9 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 
                 // Closure arguments are wrapped in a tuple, so we need to get the first
                 // from that.
-                if let ty::Tuple(elems) = argument_ty.sty {
+                if let ty::Tuple(elems) = argument_ty.kind {
                     let argument_ty = elems.first()?.expect_ty();
-                    if let ty::Ref(_, _, _) = argument_ty.sty {
+                    if let ty::Ref(_, _, _) = argument_ty.kind {
                         return Some(AnnotatedBorrowFnSignature::Closure {
                             argument_ty,
                             argument_span,
@@ -1908,7 +1905,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 let return_ty = *sig.output().skip_binder();
 
                 // We expect the first argument to be a reference.
-                match argument_ty.sty {
+                match argument_ty.kind {
                     ty::Ref(_, _, _) => {}
                     _ => return None,
                 }
diff --git a/src/librustc_mir/borrow_check/error_reporting.rs b/src/librustc_mir/borrow_check/error_reporting.rs
index 5bccd2835c980..c0c0e7a32b672 100644
--- a/src/librustc_mir/borrow_check/error_reporting.rs
+++ b/src/librustc_mir/borrow_check/error_reporting.rs
@@ -58,7 +58,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         if let TerminatorKind::Call {
             func: Operand::Constant(box Constant {
                 literal: ty::Const {
-                    ty: &ty::TyS { sty: ty::FnDef(id, _), ..  },
+                    ty: &ty::TyS { kind: ty::FnDef(id, _), ..  },
                     ..
                 },
                 ..
@@ -76,7 +76,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 };
 
                 debug!("add_moved_or_invoked_closure_note: closure={:?}", closure);
-                if let ty::Closure(did, _) = self.body.local_decls[closure].ty.sty {
+                if let ty::Closure(did, _) = self.body.local_decls[closure].ty.kind {
                     let hir_id = self.infcx.tcx.hir().as_local_hir_id(did).unwrap();
 
                     if let Some((span, name)) = self.infcx.tcx.typeck_tables_of(did)
@@ -99,7 +99,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
 
         // Check if we are just moving a closure after it has been invoked.
         if let Some(target) = target {
-            if let ty::Closure(did, _) = self.body.local_decls[target].ty.sty {
+            if let ty::Closure(did, _) = self.body.local_decls[target].ty.kind {
                 let hir_id = self.infcx.tcx.hir().as_local_hir_id(did).unwrap();
 
                 if let Some((span, name)) = self.infcx.tcx.typeck_tables_of(did)
@@ -400,7 +400,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
             // If the type is a box, the field is described from the boxed type
             self.describe_field_from_ty(&ty.boxed_ty(), field, variant_index)
         } else {
-            match ty.sty {
+            match ty.kind {
                 ty::Adt(def, _) => {
                     let variant = if let Some(idx) = variant_index {
                         assert!(def.is_enum());
@@ -558,7 +558,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         // We need to add synthesized lifetimes where appropriate. We do
         // this by hooking into the pretty printer and telling it to label the
         // lifetimes without names with the value `'0`.
-        match ty.sty {
+        match ty.kind {
             ty::Ref(ty::RegionKind::ReLateBound(_, br), _, _)
             | ty::Ref(
                 ty::RegionKind::RePlaceholder(ty::PlaceholderRegion { name: br, .. }),
@@ -578,7 +578,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
         let mut s = String::new();
         let mut printer = ty::print::FmtPrinter::new(self.infcx.tcx, &mut s, Namespace::TypeNS);
 
-        let region = match ty.sty {
+        let region = match ty.kind {
             ty::Ref(region, _, _) => {
                 match region {
                     ty::RegionKind::ReLateBound(_, br)
@@ -754,7 +754,7 @@ impl BorrowedContentSource<'tcx> {
     }
 
     fn from_call(func: Ty<'tcx>, tcx: TyCtxt<'tcx>) -> Option<Self> {
-        match func.sty {
+        match func.kind {
             ty::FnDef(def_id, substs) => {
                 let trait_id = tcx.trait_of_item(def_id)?;
 
diff --git a/src/librustc_mir/borrow_check/mod.rs b/src/librustc_mir/borrow_check/mod.rs
index 32c6dd67a4b5a..5f18d4d774dc0 100644
--- a/src/librustc_mir/borrow_check/mod.rs
+++ b/src/librustc_mir/borrow_check/mod.rs
@@ -7,7 +7,6 @@ use rustc::hir::def_id::DefId;
 use rustc::infer::InferCtxt;
 use rustc::lint::builtin::UNUSED_MUT;
 use rustc::lint::builtin::{MUTABLE_BORROW_RESERVATION_CONFLICT};
-use rustc::middle::borrowck::SignalledError;
 use rustc::mir::{AggregateKind, BasicBlock, BorrowCheckResult, BorrowKind};
 use rustc::mir::{
     ClearCrossCrate, Local, Location, Body, Mutability, Operand, Place, PlaceBase, PlaceElem,
@@ -18,7 +17,7 @@ use rustc::mir::{Terminator, TerminatorKind};
 use rustc::ty::query::Providers;
 use rustc::ty::{self, TyCtxt};
 
-use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder, Level};
+use rustc_errors::{Applicability, Diagnostic, DiagnosticBuilder};
 use rustc_data_structures::bit_set::BitSet;
 use rustc_data_structures::fx::{FxHashMap, FxHashSet};
 use rustc_data_structures::graph::dominators::Dominators;
@@ -259,10 +258,6 @@ fn do_mir_borrowck<'a, 'tcx>(
         move_error_reported: BTreeMap::new(),
         uninitialized_error_reported: Default::default(),
         errors_buffer,
-        // Only downgrade errors on Rust 2015 and refuse to do so on Rust 2018.
-        // FIXME(Centril): In Rust 1.40.0, refuse doing so on 2015 as well and
-        // proceed to throwing out the migration infrastructure.
-        disable_error_downgrading: body.span.rust_2018(),
         nonlexical_regioncx: regioncx,
         used_mut: Default::default(),
         used_mut_upvars: SmallVec::new(),
@@ -374,33 +369,6 @@ fn do_mir_borrowck<'a, 'tcx>(
     if !mbcx.errors_buffer.is_empty() {
         mbcx.errors_buffer.sort_by_key(|diag| diag.span.primary_span());
 
-        if !mbcx.disable_error_downgrading && tcx.migrate_borrowck() {
-            // When borrowck=migrate, check if AST-borrowck would
-            // error on the given code.
-
-            // rust-lang/rust#55492, rust-lang/rust#58776 check the base def id
-            // for errors. AST borrowck is responsible for aggregating
-            // `signalled_any_error` from all of the nested closures here.
-            let base_def_id = tcx.closure_base_def_id(def_id);
-
-            match tcx.borrowck(base_def_id).signalled_any_error {
-                SignalledError::NoErrorsSeen => {
-                    // if AST-borrowck signalled no errors, then
-                    // downgrade all the buffered MIR-borrowck errors
-                    // to warnings.
-
-                    for err in mbcx.errors_buffer.iter_mut() {
-                        downgrade_if_error(err);
-                    }
-                }
-                SignalledError::SawSomeError => {
-                    // if AST-borrowck signalled a (cancelled) error,
-                    // then we will just emit the buffered
-                    // MIR-borrowck errors as normal.
-                }
-            }
-        }
-
         for diag in mbcx.errors_buffer.drain(..) {
             mbcx.infcx.tcx.sess.diagnostic().emit_diagnostic(&diag);
         }
@@ -416,21 +384,6 @@ fn do_mir_borrowck<'a, 'tcx>(
     result
 }
 
-fn downgrade_if_error(diag: &mut Diagnostic) {
-    if diag.is_error() {
-        diag.level = Level::Warning;
-        diag.warn(
-            "this error has been downgraded to a warning for backwards \
-            compatibility with previous releases",
-        ).warn(
-            "this represents potential undefined behavior in your code and \
-            this warning will become a hard error in the future",
-        ).note(
-            "for more information, try `rustc --explain E0729`"
-        );
-    }
-}
-
 crate struct MirBorrowckCtxt<'cx, 'tcx> {
     crate infcx: &'cx InferCtxt<'cx, 'tcx>,
     body: &'cx Body<'tcx>,
@@ -491,9 +444,6 @@ crate struct MirBorrowckCtxt<'cx, 'tcx> {
     uninitialized_error_reported: FxHashSet<PlaceRef<'cx, 'tcx>>,
     /// Errors to be reported buffer
     errors_buffer: Vec<Diagnostic>,
-    /// If there are no errors reported by the HIR borrow checker, we downgrade
-    /// all NLL errors to warnings. Setting this flag disables downgrading.
-    disable_error_downgrading: bool,
     /// This field keeps track of all the local variables that are declared mut and are mutated.
     /// Used for the warning issued by an unused mutable local variable.
     used_mut: FxHashSet<Local>,
@@ -934,12 +884,6 @@ impl InitializationRequiringAction {
 }
 
 impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
-    /// If there are no errors reported by the HIR borrow checker, we downgrade
-    /// all NLL errors to warnings. Calling this disables downgrading.
-    crate fn disable_error_downgrading(&mut self)  {
-        self.disable_error_downgrading = true;
-    }
-
     /// Checks an access to the given place to see if it is allowed. Examines the set of borrows
     /// that are in scope, as well as which paths have been initialized, to ensure that (a) the
     /// place is initialized and (b) it is not borrowed in some way that would prevent this
@@ -1796,7 +1740,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                     // be already initialized
                     let tcx = self.infcx.tcx;
                     let base_ty = Place::ty_from(&place.base, proj_base, self.body, tcx).ty;
-                    match base_ty.sty {
+                    match base_ty.kind {
                         ty::Adt(def, _) if def.has_dtor(tcx) => {
                             self.check_if_path_or_subpath_is_moved(
                                 location, InitializationRequiringAction::Assignment,
@@ -1902,7 +1846,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                 // of the union - we should error in that case.
                 let tcx = this.infcx.tcx;
                 if let ty::Adt(def, _) =
-                    Place::ty_from(base.base, base.projection, this.body, tcx).ty.sty
+                    Place::ty_from(base.base, base.projection, this.body, tcx).ty.kind
                 {
                     if def.is_union() {
                         if this.move_data.path_map[mpi].iter().any(|moi| {
@@ -2195,7 +2139,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                             Place::ty_from(place.base, proj_base, self.body, self.infcx.tcx).ty;
 
                         // Check the kind of deref to decide
-                        match base_ty.sty {
+                        match base_ty.kind {
                             ty::Ref(_, _, mutbl) => {
                                 match mutbl {
                                     // Shared borrowed data is never mutable
diff --git a/src/librustc_mir/borrow_check/move_errors.rs b/src/librustc_mir/borrow_check/move_errors.rs
index aa732b0092a22..bf5bddadd16f1 100644
--- a/src/librustc_mir/borrow_check/move_errors.rs
+++ b/src/librustc_mir/borrow_check/move_errors.rs
@@ -335,7 +335,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
         }
 
         debug!("report: ty={:?}", ty);
-        let mut err = match ty.sty {
+        let mut err = match ty.kind {
             ty::Array(..) | ty::Slice(..) =>
                 self.cannot_move_out_of_interior_noncopy(span, ty, None),
             ty::Closure(def_id, closure_substs)
diff --git a/src/librustc_mir/borrow_check/mutability_errors.rs b/src/librustc_mir/borrow_check/mutability_errors.rs
index 14b76d97b3e57..c3aed74bcaad2 100644
--- a/src/librustc_mir/borrow_check/mutability_errors.rs
+++ b/src/librustc_mir/borrow_check/mutability_errors.rs
@@ -283,7 +283,7 @@ impl<'a, 'tcx> MirBorrowckCtxt<'a, 'tcx> {
                         // for a `self: &mut Self` to suggest removing the `&mut`.
                         if let ty::Ref(
                             _, _, hir::Mutability::MutMutable
-                        ) = local_decl.ty.sty {
+                        ) = local_decl.ty.kind {
                             true
                         } else {
                             false
@@ -630,8 +630,8 @@ fn annotate_struct_field(
     field: &mir::Field,
 ) -> Option<(Span, String)> {
     // Expect our local to be a reference to a struct of some kind.
-    if let ty::Ref(_, ty, _) = ty.sty {
-        if let ty::Adt(def, _) = ty.sty {
+    if let ty::Ref(_, ty, _) = ty.kind {
+        if let ty::Adt(def, _) = ty.kind {
             let field = def.all_fields().nth(field.index())?;
             // Use the HIR types to construct the diagnostic message.
             let hir_id = tcx.hir().as_local_hir_id(field.did)?;
diff --git a/src/librustc_mir/borrow_check/nll/explain_borrow/mod.rs b/src/librustc_mir/borrow_check/nll/explain_borrow/mod.rs
index eae2f832ba791..ff4243df6e9b8 100644
--- a/src/librustc_mir/borrow_check/nll/explain_borrow/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/explain_borrow/mod.rs
@@ -95,7 +95,7 @@ impl BorrowExplanation {
                 should_note_order,
             } => {
                 let local_decl = &body.local_decls[dropped_local];
-                let (dtor_desc, type_desc) = match local_decl.ty.sty {
+                let (dtor_desc, type_desc) = match local_decl.ty.kind {
                     // If type is an ADT that implements Drop, then
                     // simplify output by reporting just the ADT name.
                     ty::Adt(adt, _substs) if adt.has_dtor(tcx) && !adt.is_box() => (
@@ -612,7 +612,7 @@ impl<'cx, 'tcx> MirBorrowckCtxt<'cx, 'tcx> {
                             {
                                 debug!("was_captured_by_trait_object: ty={:?}", ty);
                                 // Check the type for a trait object.
-                                return match ty.sty {
+                                return match ty.kind {
                                     // `&dyn Trait`
                                     ty::Ref(_, ty, _) if ty.is_trait() => true,
                                     // `Box<dyn Trait>`
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs
index 26a89b4e7a8d1..e29e9232012bc 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/mod.rs
@@ -627,7 +627,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             (self.to_error_region(fr), self.to_error_region(outlived_fr))
         {
             if let Some(ty::TyS {
-                sty: ty::Opaque(did, substs),
+                kind: ty::Opaque(did, substs),
                 ..
             }) = infcx
                 .tcx
diff --git a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs
index 6fa94269107f5..ff77083a34dfa 100644
--- a/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs
+++ b/src/librustc_mir/borrow_check/nll/region_infer/error_reporting/region_name.rs
@@ -527,7 +527,7 @@ impl<'tcx> RegionInferenceContext<'tcx> {
             &mut vec![(argument_ty, argument_hir_ty)];
 
         while let Some((ty, hir_ty)) = search_stack.pop() {
-            match (&ty.sty, &hir_ty.node) {
+            match (&ty.kind, &hir_ty.node) {
                 // Check if the `argument_ty` is `&'X ..` where `'X`
                 // is the region we are looking for -- if so, and we have a `&T`
                 // on the RHS, then we want to highlight the `&` like so:
diff --git a/src/librustc_mir/borrow_check/nll/type_check/mod.rs b/src/librustc_mir/borrow_check/nll/type_check/mod.rs
index 6a764b19c4ddf..eadc58cc80027 100644
--- a/src/librustc_mir/borrow_check/nll/type_check/mod.rs
+++ b/src/librustc_mir/borrow_check/nll/type_check/mod.rs
@@ -314,7 +314,7 @@ impl<'a, 'b, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'tcx> {
                     );
                 }
             }
-            if let ty::FnDef(def_id, substs) = constant.literal.ty.sty {
+            if let ty::FnDef(def_id, substs) = constant.literal.ty.kind {
                 let tcx = self.tcx();
 
                 let instantiated_predicates = tcx
@@ -342,7 +342,7 @@ impl<'a, 'b, 'tcx> Visitor<'tcx> for TypeVerifier<'a, 'b, 'tcx> {
             let ty = if !local_decl.is_nonref_binding() {
                 // If we have a binding of the form `let ref x: T = ..` then remove the outermost
                 // reference so we can check the type annotation for the remaining type.
-                if let ty::Ref(_, rty, _) = local_decl.ty.sty {
+                if let ty::Ref(_, rty, _) = local_decl.ty.kind {
                     rty
                 } else {
                     bug!("{:?} with ref binding has wrong type {}", local, local_decl.ty);
@@ -424,15 +424,15 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
         let mut place_ty = match &place.base {
             PlaceBase::Local(index) =>
                 PlaceTy::from_ty(self.body.local_decls[*index].ty),
-            PlaceBase::Static(box Static { kind, ty: sty, def_id }) => {
-                let sty = self.sanitize_type(place, sty);
+            PlaceBase::Static(box Static { kind, ty, def_id }) => {
+                let san_ty = self.sanitize_type(place, ty);
                 let check_err =
                     |verifier: &mut TypeVerifier<'a, 'b, 'tcx>,
                      place: &Place<'tcx>,
                      ty,
-                     sty| {
+                     san_ty| {
                         if let Err(terr) = verifier.cx.eq_types(
-                            sty,
+                            san_ty,
                             ty,
                             location.to_locations(),
                             ConstraintCategory::Boring,
@@ -442,7 +442,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                             place,
                             "bad promoted type ({:?}: {:?}): {:?}",
                             ty,
-                            sty,
+                            san_ty,
                             terr
                         );
                         };
@@ -454,17 +454,17 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                             self.sanitize_promoted(promoted_body, location);
 
                             let promoted_ty = promoted_body.return_ty();
-                            check_err(self, place, promoted_ty, sty);
+                            check_err(self, place, promoted_ty, san_ty);
                         }
                     }
                     StaticKind::Static => {
                         let ty = self.tcx().type_of(*def_id);
                         let ty = self.cx.normalize(ty, location);
 
-                        check_err(self, place, ty, sty);
+                        check_err(self, place, ty, san_ty);
                     }
                 }
-                PlaceTy::from_ty(sty)
+                PlaceTy::from_ty(san_ty)
             }
         };
 
@@ -637,7 +637,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                 )
             }
             ProjectionElem::Subslice { from, to } => PlaceTy::from_ty(
-                match base_ty.sty {
+                match base_ty.kind {
                     ty::Array(inner, size) => {
                         let size = size.eval_usize(tcx, self.cx.param_env);
                         let min_size = (from as u64) + (to as u64);
@@ -656,7 +656,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                     _ => span_mirbug_and_err!(self, place, "slice of non-array {:?}", base_ty),
                 },
             ),
-            ProjectionElem::Downcast(maybe_name, index) => match base_ty.sty {
+            ProjectionElem::Downcast(maybe_name, index) => match base_ty.kind {
                 ty::Adt(adt_def, _substs) if adt_def.is_enum() => {
                     if index.as_usize() >= adt_def.variants.len() {
                         PlaceTy::from_ty(
@@ -738,7 +738,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
         let tcx = self.tcx();
 
         let (variant, substs) = match base_ty {
-            PlaceTy { ty, variant_index: Some(variant_index) } => match ty.sty {
+            PlaceTy { ty, variant_index: Some(variant_index) } => match ty.kind {
                 ty::Adt(adt_def, substs) => (&adt_def.variants[variant_index], substs),
                 ty::Generator(def_id, substs, _) => {
                     let mut variants = substs.state_tys(def_id, tcx);
@@ -759,7 +759,7 @@ impl<'a, 'b, 'tcx> TypeVerifier<'a, 'b, 'tcx> {
                 }
                 _ => bug!("can't have downcast of non-adt non-generator type"),
             }
-            PlaceTy { ty, variant_index: None } => match ty.sty {
+            PlaceTy { ty, variant_index: None } => match ty.kind {
                 ty::Adt(adt_def, substs) if !adt_def.is_enum() =>
                     (&adt_def.variants[VariantIdx::new(0)], substs),
                 ty::Closure(def_id, substs) => {
@@ -1142,7 +1142,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
         category: ConstraintCategory,
     ) -> Fallible<()> {
         if let Err(terr) = self.sub_types(sub, sup, locations, category) {
-            if let ty::Opaque(..) = sup.sty {
+            if let ty::Opaque(..) = sup.kind {
                 // When you have `let x: impl Foo = ...` in a closure,
                 // the resulting inferend values are stored with the
                 // def-id of the base function.
@@ -1430,7 +1430,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                 variant_index,
             } => {
                 let place_type = place.ty(body, tcx).ty;
-                let adt = match place_type.sty {
+                let adt = match place_type.kind {
                     ty::Adt(adt, _) if adt.is_enum() => adt,
                     _ => {
                         span_bug!(
@@ -1559,7 +1559,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             } => {
                 let func_ty = func.ty(body, tcx);
                 debug!("check_terminator: call, func_ty={:?}", func_ty);
-                let sig = match func_ty.sty {
+                let sig = match func_ty.kind {
                     ty::FnDef(..) | ty::FnPtr(_) => func_ty.fn_sig(tcx),
                     _ => {
                         span_mirbug!(self, term, "call to non-function {:?}", func_ty);
@@ -2056,7 +2056,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                     }
 
                     CastKind::Pointer(PointerCast::ClosureFnPointer(unsafety)) => {
-                        let sig = match op.ty(body, tcx).sty {
+                        let sig = match op.ty(body, tcx).kind {
                             ty::Closure(def_id, substs) => {
                                 substs.closure_sig_ty(def_id, tcx).fn_sig(tcx)
                             }
@@ -2125,7 +2125,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                     }
 
                     CastKind::Pointer(PointerCast::MutToConstPointer) => {
-                        let ty_from = match op.ty(body, tcx).sty {
+                        let ty_from = match op.ty(body, tcx).kind {
                             ty::RawPtr(ty::TypeAndMut {
                                 ty: ty_from,
                                 mutbl: hir::MutMutable,
@@ -2140,7 +2140,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                                 return;
                             }
                         };
-                        let ty_to = match ty.sty {
+                        let ty_to = match ty.kind {
                             ty::RawPtr(ty::TypeAndMut {
                                 ty: ty_to,
                                 mutbl: hir::MutImmutable,
@@ -2173,11 +2173,11 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                     }
 
                     CastKind::Misc => {
-                        if let ty::Ref(_, mut ty_from, _) = op.ty(body, tcx).sty {
+                        if let ty::Ref(_, mut ty_from, _) = op.ty(body, tcx).kind {
                             let (mut ty_to, mutability) = if let ty::RawPtr(ty::TypeAndMut {
                                 ty: ty_to,
                                 mutbl,
-                            }) = ty.sty {
+                            }) = ty.kind {
                                 (ty_to, mutbl)
                             } else {
                                 span_mirbug!(
@@ -2192,9 +2192,9 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
 
                             // Handle the direct cast from `&[T; N]` to `*const T` by unwrapping
                             // any array we find.
-                            while let ty::Array(ty_elem_from, _) = ty_from.sty {
+                            while let ty::Array(ty_elem_from, _) = ty_from.kind {
                                 ty_from = ty_elem_from;
-                                if let ty::Array(ty_elem_to, _) = ty_to.sty {
+                                if let ty::Array(ty_elem_to, _) = ty_to.kind {
                                     ty_to = ty_elem_to;
                                 } else {
                                     break;
@@ -2250,7 +2250,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
             | Rvalue::BinaryOp(BinOp::Gt, left, right)
             | Rvalue::BinaryOp(BinOp::Ge, left, right) => {
                 let ty_left = left.ty(body, tcx);
-                if let ty::RawPtr(_) | ty::FnPtr(_) = ty_left.sty {
+                if let ty::RawPtr(_) | ty::FnPtr(_) = ty_left.kind {
                     let ty_right = right.ty(body, tcx);
                     let common_ty = self.infcx.next_ty_var(
                         TypeVariableOrigin {
@@ -2431,7 +2431,7 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
                     let base_ty = Place::ty_from(&borrowed_place.base, proj_base, body, tcx).ty;
 
                     debug!("add_reborrow_constraint - base_ty = {:?}", base_ty);
-                    match base_ty.sty {
+                    match base_ty.kind {
                         ty::Ref(ref_region, _, mutbl) => {
                             constraints.outlives_constraints.push(OutlivesConstraint {
                                 sup: ref_region.to_region_vid(),
diff --git a/src/librustc_mir/borrow_check/nll/universal_regions.rs b/src/librustc_mir/borrow_check/nll/universal_regions.rs
index 3e090aed52270..b5af97a2217e8 100644
--- a/src/librustc_mir/borrow_check/nll/universal_regions.rs
+++ b/src/librustc_mir/borrow_check/nll/universal_regions.rs
@@ -486,7 +486,7 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
                 let defining_ty = self.infcx
                     .replace_free_regions_with_nll_infer_vars(FR, &defining_ty);
 
-                match defining_ty.sty {
+                match defining_ty.kind {
                     ty::Closure(def_id, substs) => DefiningTy::Closure(def_id, substs),
                     ty::Generator(def_id, substs, movability) => {
                         DefiningTy::Generator(def_id, substs, movability)
@@ -573,7 +573,7 @@ impl<'cx, 'tcx> UniversalRegionsBuilder<'cx, 'tcx> {
                         // flattens this tuple.
                         let (&output, tuplized_inputs) = inputs_and_output.split_last().unwrap();
                         assert_eq!(tuplized_inputs.len(), 1, "multiple closure inputs");
-                        let inputs = match tuplized_inputs[0].sty {
+                        let inputs = match tuplized_inputs[0].kind {
                             ty::Tuple(inputs) => inputs,
                             _ => bug!("closure inputs not a tuple: {:?}", tuplized_inputs[0]),
                         };
diff --git a/src/librustc_mir/borrow_check/place_ext.rs b/src/librustc_mir/borrow_check/place_ext.rs
index 411fa5b596765..f437c7172966b 100644
--- a/src/librustc_mir/borrow_check/place_ext.rs
+++ b/src/librustc_mir/borrow_check/place_ext.rs
@@ -57,7 +57,7 @@ impl<'tcx> PlaceExt<'tcx> for Place<'tcx> {
 
             if *elem == ProjectionElem::Deref {
                 let ty = Place::ty_from(&self.base, proj_base, body, tcx).ty;
-                if let ty::RawPtr(..) | ty::Ref(_, _, hir::MutImmutable) = ty.sty {
+                if let ty::RawPtr(..) | ty::Ref(_, _, hir::MutImmutable) = ty.kind {
                     // For both derefs of raw pointers and `&T`
                     // references, the original path is `Copy` and
                     // therefore not significant.  In particular,
diff --git a/src/librustc_mir/borrow_check/places_conflict.rs b/src/librustc_mir/borrow_check/places_conflict.rs
index dafa0b6631fe2..9dd3e119c217a 100644
--- a/src/librustc_mir/borrow_check/places_conflict.rs
+++ b/src/librustc_mir/borrow_check/places_conflict.rs
@@ -231,7 +231,7 @@ fn place_components_conflict<'tcx>(
             let proj_base = &borrow_place.projection[..access_place.projection.len() + i];
             let base_ty = Place::ty_from(borrow_base, proj_base, body, tcx).ty;
 
-            match (elem, &base_ty.sty, access) {
+            match (elem, &base_ty.kind, access) {
                 (_, _, Shallow(Some(ArtificialField::ArrayLength)))
                 | (_, _, Shallow(Some(ArtificialField::ShallowBorrow))) => {
                     // The array length is like  additional fields on the
@@ -349,7 +349,7 @@ fn place_base_conflict<'tcx>(
                 },
                 (StaticKind::Promoted(promoted_1, _), StaticKind::Promoted(promoted_2, _)) => {
                     if promoted_1 == promoted_2 {
-                        if let ty::Array(_, len) = s1.ty.sty {
+                        if let ty::Array(_, len) = s1.ty.kind {
                             if let Some(0) = len.try_eval_usize(tcx, param_env) {
                                 // Ignore conflicts with promoted [T; 0].
                                 debug!("place_element_conflict: IGNORE-LEN-0-PROMOTED");
@@ -404,7 +404,7 @@ fn place_projection_conflict<'tcx>(
                 Overlap::EqualOrDisjoint
             } else {
                 let ty = Place::ty_from(pi1_base, pi1_proj_base, body, tcx).ty;
-                match ty.sty {
+                match ty.kind {
                     ty::Adt(def, _) if def.is_union() => {
                         // Different fields of a union, we are basically stuck.
                         debug!("place_element_conflict: STUCK-UNION");
diff --git a/src/librustc_mir/borrow_check/prefixes.rs b/src/librustc_mir/borrow_check/prefixes.rs
index 0a268ec134023..a46a1cc5647a9 100644
--- a/src/librustc_mir/borrow_check/prefixes.rs
+++ b/src/librustc_mir/borrow_check/prefixes.rs
@@ -144,7 +144,7 @@ impl<'cx, 'tcx> Iterator for Prefixes<'cx, 'tcx> {
                     // reference.
 
                     let ty = Place::ty_from(cursor.base, proj_base, self.body, self.tcx).ty;
-                    match ty.sty {
+                    match ty.kind {
                         ty::RawPtr(_) |
                         ty::Ref(
                             _, /*rgn*/
diff --git a/src/librustc_mir/build/expr/into.rs b/src/librustc_mir/build/expr/into.rs
index 30d53502b11ff..8a6bc5a2a764e 100644
--- a/src/librustc_mir/build/expr/into.rs
+++ b/src/librustc_mir/build/expr/into.rs
@@ -196,7 +196,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
                 exit_block.unit()
             }
             ExprKind::Call { ty, fun, args, from_hir_call } => {
-                let intrinsic = match ty.sty {
+                let intrinsic = match ty.kind {
                     ty::FnDef(def_id, _) => {
                         let f = ty.fn_sig(this.hir.tcx());
                         if f.abi() == Abi::RustIntrinsic || f.abi() == Abi::PlatformIntrinsic {
diff --git a/src/librustc_mir/build/matches/simplify.rs b/src/librustc_mir/build/matches/simplify.rs
index 8d049b53988a9..224b1a2b4efee 100644
--- a/src/librustc_mir/build/matches/simplify.rs
+++ b/src/librustc_mir/build/matches/simplify.rs
@@ -109,7 +109,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             }
 
             PatternKind::Range(PatternRange { lo, hi, end }) => {
-                let (range, bias) = match lo.ty.sty {
+                let (range, bias) = match lo.ty.kind {
                     ty::Char => {
                         (Some(('\u{0000}' as u128, '\u{10FFFF}' as u128, Size::from_bits(32))), 0)
                     }
diff --git a/src/librustc_mir/build/matches/test.rs b/src/librustc_mir/build/matches/test.rs
index d5890d00ea80f..03f9e4ccc970b 100644
--- a/src/librustc_mir/build/matches/test.rs
+++ b/src/librustc_mir/build/matches/test.rs
@@ -229,7 +229,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
 
             TestKind::SwitchInt { switch_ty, ref options, indices: _ } => {
                 let target_blocks = make_target_blocks(self);
-                let terminator = if switch_ty.sty == ty::Bool {
+                let terminator = if switch_ty.kind == ty::Bool {
                     assert!(options.len() > 0 && options.len() <= 2);
                     if let [first_bb, second_bb] = *target_blocks {
                         let (true_bb, false_bb) = match options[0] {
@@ -400,8 +400,8 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
         // We want to do this even when the scrutinee is a reference to an
         // array, so we can call `<[u8]>::eq` rather than having to find an
         // `<[u8; N]>::eq`.
-        let unsize = |ty: Ty<'tcx>| match ty.sty {
-            ty::Ref(region, rty, _) => match rty.sty {
+        let unsize = |ty: Ty<'tcx>| match ty.kind {
+            ty::Ref(region, rty, _) => match rty.kind {
                 ty::Array(inner_ty, n) => Some((region, inner_ty, n)),
                 _ => None,
             },
@@ -438,7 +438,7 @@ impl<'a, 'tcx> Builder<'a, 'tcx> {
             },
         }
 
-        let deref_ty = match ty.sty {
+        let deref_ty = match ty.kind {
             ty::Ref(_, deref_ty, _) => deref_ty,
             _ => bug!("non_scalar_compare called on non-reference type: {}", ty),
         };
diff --git a/src/librustc_mir/build/mod.rs b/src/librustc_mir/build/mod.rs
index 647d7515fe98d..b0572df9d0853 100644
--- a/src/librustc_mir/build/mod.rs
+++ b/src/librustc_mir/build/mod.rs
@@ -73,7 +73,7 @@ pub fn mir_build(tcx: TyCtxt<'_>, def_id: DefId) -> Body<'_> {
 
             let ty = tcx.type_of(fn_def_id);
             let mut abi = fn_sig.abi;
-            let implicit_argument = match ty.sty {
+            let implicit_argument = match ty.kind {
                 ty::Closure(..) => {
                     // HACK(eddyb) Avoid having RustCall on closures,
                     // as it adds unnecessary (and wrong) auto-tupling.
@@ -127,7 +127,7 @@ pub fn mir_build(tcx: TyCtxt<'_>, def_id: DefId) -> Body<'_> {
             let arguments = implicit_argument.into_iter().chain(explicit_arguments);
 
             let (yield_ty, return_ty) = if body.generator_kind.is_some() {
-                let gen_sig = match ty.sty {
+                let gen_sig = match ty.kind {
                     ty::Generator(gen_def_id, gen_substs, ..) =>
                         gen_substs.sig(gen_def_id, tcx),
                     _ =>
@@ -178,7 +178,7 @@ fn liberated_closure_env_ty(
 ) -> Ty<'_> {
     let closure_ty = tcx.body_tables(body_id).node_type(closure_expr_id);
 
-    let (closure_def_id, closure_substs) = match closure_ty.sty {
+    let (closure_def_id, closure_substs) = match closure_ty.kind {
         ty::Closure(closure_def_id, closure_substs) => (closure_def_id, closure_substs),
         _ => bug!("closure expr does not have closure type: {:?}", closure_ty)
     };
diff --git a/src/librustc_mir/const_eval.rs b/src/librustc_mir/const_eval.rs
index 435159827e6c3..ca238867421ab 100644
--- a/src/librustc_mir/const_eval.rs
+++ b/src/librustc_mir/const_eval.rs
@@ -63,8 +63,8 @@ fn op_to_const<'tcx>(
     // `Undef` situation.
     let try_as_immediate = match op.layout.abi {
         layout::Abi::Scalar(..) => true,
-        layout::Abi::ScalarPair(..) => match op.layout.ty.sty {
-            ty::Ref(_, inner, _) => match inner.sty {
+        layout::Abi::ScalarPair(..) => match op.layout.ty.kind {
+            ty::Ref(_, inner, _) => match inner.kind {
                 ty::Slice(elem) => elem == ecx.tcx.types.u8,
                 ty::Str => true,
                 _ => false,
@@ -608,7 +608,7 @@ pub fn const_eval_provider<'tcx>(
     // Catch such calls and evaluate them instead of trying to load a constant's MIR.
     if let ty::InstanceDef::Intrinsic(def_id) = key.value.instance.def {
         let ty = key.value.instance.ty(tcx);
-        let substs = match ty.sty {
+        let substs = match ty.kind {
             ty::FnDef(_, substs) => substs,
             _ => bug!("intrinsic with type {:?}", ty),
         };
diff --git a/src/librustc_mir/dataflow/drop_flag_effects.rs b/src/librustc_mir/dataflow/drop_flag_effects.rs
index 444cc008ae785..51b717b69e9c1 100644
--- a/src/librustc_mir/dataflow/drop_flag_effects.rs
+++ b/src/librustc_mir/dataflow/drop_flag_effects.rs
@@ -50,7 +50,7 @@ fn place_contents_drop_state_cannot_differ<'tcx>(
     place: &mir::Place<'tcx>,
 ) -> bool {
     let ty = place.ty(body, tcx).ty;
-    match ty.sty {
+    match ty.kind {
         ty::Array(..) => {
             debug!("place_contents_drop_state_cannot_differ place: {:?} ty: {:?} => false",
                    place, ty);
diff --git a/src/librustc_mir/dataflow/move_paths/builder.rs b/src/librustc_mir/dataflow/move_paths/builder.rs
index 698c50166270a..d9119253cae5f 100644
--- a/src/librustc_mir/dataflow/move_paths/builder.rs
+++ b/src/librustc_mir/dataflow/move_paths/builder.rs
@@ -106,7 +106,7 @@ impl<'b, 'a, 'tcx> Gatherer<'b, 'a, 'tcx> {
             let body = self.builder.body;
             let tcx = self.builder.tcx;
             let place_ty = Place::ty_from(&place.base, proj_base, body, tcx).ty;
-            match place_ty.sty {
+            match place_ty.kind {
                 ty::Ref(..) | ty::RawPtr(..) => {
                     let proj = &place.projection[..i+1];
                     return Err(MoveError::cannot_move_out_of(
@@ -438,7 +438,7 @@ impl<'b, 'a, 'tcx> Gatherer<'b, 'a, 'tcx> {
         // of the union so it is marked as initialized again.
         if let [proj_base @ .., ProjectionElem::Field(_, _)] = place.projection {
             if let ty::Adt(def, _) =
-                Place::ty_from(place.base, proj_base, self.builder.body, self.builder.tcx).ty.sty
+                Place::ty_from(place.base, proj_base, self.builder.body, self.builder.tcx).ty.kind
             {
                 if def.is_union() {
                     place = PlaceRef { base: place.base, projection: proj_base }
diff --git a/src/librustc_mir/hair/constant.rs b/src/librustc_mir/hair/constant.rs
index bc01e3ee95b97..956716f8ceaf7 100644
--- a/src/librustc_mir/hair/constant.rs
+++ b/src/librustc_mir/hair/constant.rs
@@ -49,7 +49,7 @@ crate fn lit_to_const<'tcx>(
             parse_float(n, fty, neg).map_err(|_| LitToConstError::UnparseableFloat)?
         }
         LitKind::FloatUnsuffixed(n) => {
-            let fty = match ty.sty {
+            let fty = match ty.kind {
                 ty::Float(fty) => fty,
                 _ => bug!()
             };
diff --git a/src/librustc_mir/hair/cx/expr.rs b/src/librustc_mir/hair/cx/expr.rs
index bdfcacd0f4629..a24b14598eb59 100644
--- a/src/librustc_mir/hair/cx/expr.rs
+++ b/src/librustc_mir/hair/cx/expr.rs
@@ -442,7 +442,7 @@ fn make_mirror_unadjusted<'a, 'tcx>(
         }
 
         hir::ExprKind::Struct(ref qpath, ref fields, ref base) => {
-            match expr_ty.sty {
+            match expr_ty.kind {
                 ty::Adt(adt, substs) => {
                     match adt.adt_kind() {
                         AdtKind::Struct | AdtKind::Union => {
@@ -505,7 +505,7 @@ fn make_mirror_unadjusted<'a, 'tcx>(
 
         hir::ExprKind::Closure(..) => {
             let closure_ty = cx.tables().expr_ty(expr);
-            let (def_id, substs, movability) = match closure_ty.sty {
+            let (def_id, substs, movability) = match closure_ty.kind {
                 ty::Closure(def_id, substs) => (def_id, UpvarSubsts::Closure(substs), None),
                 ty::Generator(def_id, substs, movability) => {
                     (def_id, UpvarSubsts::Generator(substs), Some(movability))
@@ -938,7 +938,7 @@ fn convert_path_expr<'a, 'tcx>(
             let user_provided_type = user_provided_types.get(expr.hir_id).map(|u_ty| *u_ty);
             debug!("convert_path_expr: user_provided_type={:?}", user_provided_type);
             let ty = cx.tables().node_type(expr.hir_id);
-            match ty.sty {
+            match ty.kind {
                 // A unit struct/variant which is used as a value.
                 // We return a completely different ExprKind here to account for this special case.
                 ty::Adt(adt_def, substs) => {
@@ -1001,7 +1001,7 @@ fn convert_var(
             });
             let region = cx.tcx.mk_region(region);
 
-            let self_expr = if let ty::Closure(_, closure_substs) = closure_ty.sty {
+            let self_expr = if let ty::Closure(_, closure_substs) = closure_ty.kind {
                 match cx.infcx.closure_kind(closure_def_id, closure_substs).unwrap() {
                     ty::ClosureKind::Fn => {
                         let ref_closure_ty = cx.tcx.mk_ref(region,
@@ -1147,7 +1147,7 @@ fn overloaded_place<'a, 'tcx>(
     // Reconstruct the output assuming it's a reference with the
     // same region and mutability as the receiver. This holds for
     // `Deref(Mut)::Deref(_mut)` and `Index(Mut)::index(_mut)`.
-    let (region, mutbl) = match recv_ty.sty {
+    let (region, mutbl) = match recv_ty.kind {
         ty::Ref(region, _, mutbl) => (region, mutbl),
         _ => span_bug!(expr.span, "overloaded_place: receiver is not a reference"),
     };
diff --git a/src/librustc_mir/hair/pattern/_match.rs b/src/librustc_mir/hair/pattern/_match.rs
index a6d955f336910..e570ace8df1d2 100644
--- a/src/librustc_mir/hair/pattern/_match.rs
+++ b/src/librustc_mir/hair/pattern/_match.rs
@@ -213,7 +213,7 @@ impl LiteralExpander<'tcx> {
         crty: Ty<'tcx>,
     ) -> ConstValue<'tcx> {
         debug!("fold_const_value_deref {:?} {:?} {:?}", val, rty, crty);
-        match (val, &crty.sty, &rty.sty) {
+        match (val, &crty.kind, &rty.kind) {
             // the easy case, deref a reference
             (ConstValue::Scalar(Scalar::Ptr(p)), x, y) if x == y => {
                 let alloc = self.tcx.alloc_map.lock().unwrap_memory(p.alloc_id);
@@ -244,13 +244,13 @@ impl LiteralExpander<'tcx> {
 
 impl PatternFolder<'tcx> for LiteralExpander<'tcx> {
     fn fold_pattern(&mut self, pat: &Pattern<'tcx>) -> Pattern<'tcx> {
-        debug!("fold_pattern {:?} {:?} {:?}", pat, pat.ty.sty, pat.kind);
-        match (&pat.ty.sty, &*pat.kind) {
+        debug!("fold_pattern {:?} {:?} {:?}", pat, pat.ty.kind, pat.kind);
+        match (&pat.ty.kind, &*pat.kind) {
             (
                 &ty::Ref(_, rty, _),
                 &PatternKind::Constant { value: Const {
                     val,
-                    ty: ty::TyS { sty: ty::Ref(_, crty, _), .. },
+                    ty: ty::TyS { kind: ty::Ref(_, crty, _), .. },
                 } },
             ) => {
                 Pattern {
@@ -406,14 +406,14 @@ impl<'a, 'tcx> MatchCheckCtxt<'a, 'tcx> {
     }
 
     fn is_non_exhaustive_enum(&self, ty: Ty<'tcx>) -> bool {
-        match ty.sty {
+        match ty.kind {
             ty::Adt(adt_def, ..) => adt_def.is_variant_list_non_exhaustive(),
             _ => false,
         }
     }
 
     fn is_local(&self, ty: Ty<'tcx>) -> bool {
-        match ty.sty {
+        match ty.kind {
             ty::Adt(adt_def, ..) => adt_def.did.is_local(),
             _ => false,
         }
@@ -565,7 +565,7 @@ impl<'tcx> Witness<'tcx> {
             let len = self.0.len() as u64;
             let mut pats = self.0.drain((len - arity) as usize..).rev();
 
-            match ty.sty {
+            match ty.kind {
                 ty::Adt(..) |
                 ty::Tuple(..) => {
                     let pats = pats.enumerate().map(|(i, p)| {
@@ -575,7 +575,7 @@ impl<'tcx> Witness<'tcx> {
                         }
                     }).collect();
 
-                    if let ty::Adt(adt, substs) = ty.sty {
+                    if let ty::Adt(adt, substs) = ty.kind {
                         if adt.is_enum() {
                             PatternKind::Variant {
                                 adt_def: adt,
@@ -639,7 +639,7 @@ fn all_constructors<'a, 'tcx>(
     pcx: PatternContext<'tcx>,
 ) -> Vec<Constructor<'tcx>> {
     debug!("all_constructors({:?})", pcx.ty);
-    let ctors = match pcx.ty.sty {
+    let ctors = match pcx.ty.kind {
         ty::Bool => {
             [true, false].iter().map(|&b| {
                 ConstantValue(ty::Const::from_bool(cx.tcx, b))
@@ -785,7 +785,7 @@ where
         match *row.kind {
             PatternKind::Constant { value } => {
                 // extract the length of an array/slice from a constant
-                match (value.val, &value.ty.sty) {
+                match (value.val, &value.ty.kind) {
                     (_, ty::Array(_, n)) => max_fixed_len = cmp::max(
                         max_fixed_len,
                         n.eval_usize(cx.tcx, cx.param_env),
@@ -837,7 +837,7 @@ impl<'tcx> IntRange<'tcx> {
         // Floating-point ranges are permitted and we don't want
         // to consider them when constructing integer ranges.
         fn is_integral(ty: Ty<'_>) -> bool {
-            match ty.sty {
+            match ty.kind {
                 ty::Char | ty::Int(_) | ty::Uint(_) => true,
                 _ => false,
             }
@@ -896,7 +896,7 @@ impl<'tcx> IntRange<'tcx> {
 
     // The return value of `signed_bias` should be XORed with an endpoint to encode/decode it.
     fn signed_bias(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>) -> u128 {
-        match ty.sty {
+        match ty.kind {
             ty::Int(ity) => {
                 let bits = Integer::from_attr(&tcx, SignedInt(ity)).size().bits() as u128;
                 1u128 << (bits - 1)
@@ -1345,7 +1345,7 @@ fn pat_constructors<'tcx>(cx: &mut MatchCheckCtxt<'_, 'tcx>,
                 lo.ty,
                 end,
             )]),
-        PatternKind::Array { .. } => match pcx.ty.sty {
+        PatternKind::Array { .. } => match pcx.ty.kind {
             ty::Array(_, length) => Some(vec![
                 Slice(length.eval_usize(cx.tcx, cx.param_env))
             ]),
@@ -1372,7 +1372,7 @@ fn pat_constructors<'tcx>(cx: &mut MatchCheckCtxt<'_, 'tcx>,
 /// A struct pattern's arity is the number of fields it contains, etc.
 fn constructor_arity(cx: &MatchCheckCtxt<'a, 'tcx>, ctor: &Constructor<'tcx>, ty: Ty<'tcx>) -> u64 {
     debug!("constructor_arity({:#?}, {:?})", ctor, ty);
-    match ty.sty {
+    match ty.kind {
         ty::Tuple(ref fs) => fs.len() as u64,
         ty::Slice(..) | ty::Array(..) => match *ctor {
             Slice(length) => length,
@@ -1397,7 +1397,7 @@ fn constructor_sub_pattern_tys<'a, 'tcx>(
     ty: Ty<'tcx>,
 ) -> Vec<Ty<'tcx>> {
     debug!("constructor_sub_pattern_tys({:#?}, {:?})", ctor, ty);
-    match ty.sty {
+    match ty.kind {
         ty::Tuple(ref fs) => fs.into_iter().map(|t| t.expect_ty()).collect(),
         ty::Slice(ty) | ty::Array(ty, _) => match *ctor {
             Slice(length) => (0..length).map(|_| ty).collect(),
@@ -1415,7 +1415,7 @@ fn constructor_sub_pattern_tys<'a, 'tcx>(
                         || field.vis.is_accessible_from(cx.module, cx.tcx);
                     if is_visible {
                         let ty = field.ty(cx.tcx, substs);
-                        match ty.sty {
+                        match ty.kind {
                             // If the field type returned is an array of an unknown
                             // size return an TyErr.
                             ty::Array(_, len)
@@ -1451,7 +1451,7 @@ fn slice_pat_covered_by_const<'tcx>(
     suffix: &[Pattern<'tcx>],
     param_env: ty::ParamEnv<'tcx>,
 ) -> Result<bool, ErrorReported> {
-    let data: &[u8] = match (const_val.val, &const_val.ty.sty) {
+    let data: &[u8] = match (const_val.val, &const_val.ty.kind) {
         (ConstValue::ByRef { offset, alloc, .. }, ty::Array(t, n)) => {
             assert_eq!(*t, tcx.types.u8);
             let n = n.eval_usize(tcx, param_env);
@@ -1503,7 +1503,7 @@ fn should_treat_range_exhaustively(tcx: TyCtxt<'tcx>, ctor: &Constructor<'tcx>)
         ConstantRange(_, _, ty, _) => ty,
         _ => return false,
     };
-    if let ty::Char | ty::Int(_) | ty::Uint(_) = ty.sty {
+    if let ty::Char | ty::Int(_) | ty::Uint(_) = ty.kind {
         !ty.is_ptr_sized_integral() || tcx.features().precise_pointer_size_matching
     } else {
         false
@@ -1775,7 +1775,7 @@ fn specialize<'p, 'a: 'p, 'tcx>(
                     // necessarily point to memory, they are usually just integers. The only time
                     // they should be pointing to memory is when they are subslices of nonzero
                     // slices
-                    let (alloc, offset, n, ty) = match value.ty.sty {
+                    let (alloc, offset, n, ty) = match value.ty.kind {
                         ty::Array(t, n) => {
                             match value.val {
                                 ConstValue::ByRef { offset, alloc, .. } => (
diff --git a/src/librustc_mir/hair/pattern/check_match.rs b/src/librustc_mir/hair/pattern/check_match.rs
index 6301d9c390b02..3791ae1c41e4a 100644
--- a/src/librustc_mir/hair/pattern/check_match.rs
+++ b/src/librustc_mir/hair/pattern/check_match.rs
@@ -186,7 +186,7 @@ impl<'tcx> MatchVisitor<'_, 'tcx> {
                 let scrutinee_is_uninhabited = if self.tcx.features().exhaustive_patterns {
                     self.tcx.is_ty_uninhabited_from(module, pat_ty)
                 } else {
-                    match pat_ty.sty {
+                    match pat_ty.kind {
                         ty::Never => true,
                         ty::Adt(def, _) => {
                             def_span = self.tcx.hir().span_if_local(def.did);
@@ -293,7 +293,7 @@ fn check_for_bindings_named_same_as_variants(cx: &MatchVisitor<'_, '_>, pat: &Pa
                     return true;
                 }
                 let pat_ty = cx.tables.pat_ty(p);
-                if let ty::Adt(edef, _) = pat_ty.sty {
+                if let ty::Adt(edef, _) = pat_ty.kind {
                     if edef.is_enum() && edef.variants.iter().any(|variant| {
                         variant.ident == ident && variant.ctor_kind == CtorKind::Const
                     }) {
@@ -487,7 +487,7 @@ fn adt_defined_here(
     witnesses: &[Pattern<'_>],
 ) {
     let ty = ty.peel_refs();
-    if let ty::Adt(def, _) = ty.sty {
+    if let ty::Adt(def, _) = ty.kind {
         if let Some(sp) = cx.tcx.hir().span_if_local(def.did) {
             err.span_label(sp, format!("`{}` defined here", ty));
         }
@@ -502,7 +502,7 @@ fn adt_defined_here(
 
 fn maybe_point_at_variant(ty: Ty<'_>, patterns: &[Pattern<'_>]) -> Vec<Span> {
     let mut covered = vec![];
-    if let ty::Adt(def, _) = ty.sty {
+    if let ty::Adt(def, _) = ty.kind {
         // Don't point at variants that have already been covered due to other patterns to avoid
         // visual clutter.
         for pattern in patterns {
diff --git a/src/librustc_mir/hair/pattern/mod.rs b/src/librustc_mir/hair/pattern/mod.rs
index 4aaa5e8ee259a..162251bf76e7f 100644
--- a/src/librustc_mir/hair/pattern/mod.rs
+++ b/src/librustc_mir/hair/pattern/mod.rs
@@ -231,7 +231,7 @@ impl<'tcx> fmt::Display for Pattern<'tcx> {
                     PatternKind::Variant { adt_def, variant_index, .. } => {
                         Some(&adt_def.variants[variant_index])
                     }
-                    _ => if let ty::Adt(adt, _) = self.ty.sty {
+                    _ => if let ty::Adt(adt, _) = self.ty.kind {
                         if !adt.is_enum() {
                             Some(&adt.variants[VariantIdx::new(0)])
                         } else {
@@ -295,7 +295,7 @@ impl<'tcx> fmt::Display for Pattern<'tcx> {
                 Ok(())
             }
             PatternKind::Deref { ref subpattern } => {
-                match self.ty.sty {
+                match self.ty.kind {
                     ty::Adt(def, _) if def.is_box() => write!(f, "box ")?,
                     ty::Ref(_, _, mutbl) => {
                         write!(f, "&")?;
@@ -548,7 +548,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
             }
 
             PatKind::Slice(ref prefix, ref slice, ref suffix) => {
-                match ty.sty {
+                match ty.kind {
                     ty::Ref(_, ty, _) =>
                         PatternKind::Deref {
                             subpattern: Pattern {
@@ -573,7 +573,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
             }
 
             PatKind::Tuple(ref subpatterns, ddpos) => {
-                match ty.sty {
+                match ty.kind {
                     ty::Tuple(ref tys) => {
                         let subpatterns =
                             subpatterns.iter()
@@ -595,7 +595,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
 
             PatKind::Binding(_, id, ident, ref sub) => {
                 let var_ty = self.tables.node_type(pat.hir_id);
-                if let ty::Error = var_ty.sty {
+                if let ty::Error = var_ty.kind {
                     // Avoid ICE
                     return Pattern { span: pat.span, ty, kind: Box::new(PatternKind::Wild) };
                 };
@@ -617,7 +617,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
                 // A ref x pattern is the same node used for x, and as such it has
                 // x's type, which is &T, where we want T (the type being matched).
                 if let ty::BindByReference(_) = bm {
-                    if let ty::Ref(_, rty, _) = ty.sty {
+                    if let ty::Ref(_, rty, _) = ty.kind {
                         ty = rty;
                     } else {
                         bug!("`ref {}` has wrong type {}", ident, ty);
@@ -636,7 +636,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
 
             PatKind::TupleStruct(ref qpath, ref subpatterns, ddpos) => {
                 let res = self.tables.qpath_res(qpath, pat.hir_id);
-                let adt_def = match ty.sty {
+                let adt_def = match ty.kind {
                     ty::Adt(adt_def, _) => adt_def,
                     ty::Error => { // Avoid ICE (#50585)
                         return Pattern { span: pat.span, ty, kind: Box::new(PatternKind::Wild) };
@@ -747,7 +747,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
         let (prefix, slice, suffix) =
             self.flatten_nested_slice_patterns(prefix, slice, suffix);
 
-        match ty.sty {
+        match ty.kind {
             ty::Slice(..) => {
                 // matching a slice or fixed-length array
                 PatternKind::Slice { prefix: prefix, slice: slice, suffix: suffix }
@@ -787,7 +787,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
                 let enum_id = self.tcx.parent(variant_id).unwrap();
                 let adt_def = self.tcx.adt_def(enum_id);
                 if adt_def.is_enum() {
-                    let substs = match ty.sty {
+                    let substs = match ty.kind {
                         ty::Adt(_, substs) |
                         ty::FnDef(_, substs) => substs,
                         ty::Error => {  // Avoid ICE (#50585)
@@ -1077,7 +1077,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
         };
 
 
-        let kind = match cv.ty.sty {
+        let kind = match cv.ty.kind {
             ty::Float(_) => {
                 self.tcx.lint_hir(
                     ::rustc::lint::builtin::ILLEGAL_FLOATING_POINT_LITERAL_PATTERN,
@@ -1109,7 +1109,7 @@ impl<'a, 'tcx> PatternContext<'a, 'tcx> {
                 PatternKind::Wild
             }
             // keep old code until future-compat upgraded to errors.
-            ty::Ref(_, ty::TyS { sty: ty::Adt(adt_def, _), .. }, _)
+            ty::Ref(_, ty::TyS { kind: ty::Adt(adt_def, _), .. }, _)
             if !self.tcx.has_attr(adt_def.did, sym::structural_match) => {
                 // HACK(estebank): Side-step ICE #53708, but anything other than erroring here
                 // would be wrong. Returnging `PatternKind::Wild` is not technically correct.
@@ -1224,7 +1224,7 @@ fn search_for_adt_without_structural_match<'tcx>(tcx: TyCtxt<'tcx>,
         fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
             debug!("Search visiting ty: {:?}", ty);
 
-            let (adt_def, substs) = match ty.sty {
+            let (adt_def, substs) = match ty.kind {
                 ty::Adt(adt_def, substs) => (adt_def, substs),
                 ty::RawPtr(..) => {
                     // `#[structural_match]` ignores substructure of
@@ -1501,7 +1501,7 @@ pub fn compare_const_vals<'tcx>(
 
     if let (Some(a), Some(b)) = (a_bits, b_bits) {
         use ::rustc_apfloat::Float;
-        return match ty.sty {
+        return match ty.kind {
             ty::Float(ast::FloatTy::F32) => {
                 let l = ::rustc_apfloat::ieee::Single::from_bits(a);
                 let r = ::rustc_apfloat::ieee::Single::from_bits(b);
@@ -1524,7 +1524,7 @@ pub fn compare_const_vals<'tcx>(
         }
     }
 
-    if let ty::Str = ty.sty {
+    if let ty::Str = ty.kind {
         match (a.val, b.val) {
             (
                 ConstValue::Slice { data: alloc_a, start: offset_a, end: end_a },
diff --git a/src/librustc_mir/hair/util.rs b/src/librustc_mir/hair/util.rs
index 4e014855df5e0..d63541f7a3f56 100644
--- a/src/librustc_mir/hair/util.rs
+++ b/src/librustc_mir/hair/util.rs
@@ -17,7 +17,7 @@ crate trait UserAnnotatedTyHelpers<'tcx> {
         let mut user_ty = *user_provided_types.get(hir_id)?;
         debug!("user_subts_applied_to_ty_of_hir_id: user_ty={:?}", user_ty);
         let ty = self.tables().node_type(hir_id);
-        match ty.sty {
+        match ty.kind {
             ty::Adt(adt_def, ..) => {
                 if let UserType::TypeOf(ref mut did, _) = &mut user_ty.value {
                     *did = adt_def.did;
diff --git a/src/librustc_mir/interpret/cast.rs b/src/librustc_mir/interpret/cast.rs
index 210647ac1e9a3..d120412c901a6 100644
--- a/src/librustc_mir/interpret/cast.rs
+++ b/src/librustc_mir/interpret/cast.rs
@@ -34,7 +34,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
 
             Pointer(PointerCast::ReifyFnPointer) => {
                 // The src operand does not matter, just its type
-                match src.layout.ty.sty {
+                match src.layout.ty.kind {
                     ty::FnDef(def_id, substs) => {
                         // All reifications must be monomorphic, bail out otherwise.
                         if src.layout.ty.needs_subst() {
@@ -54,7 +54,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
 
             Pointer(PointerCast::UnsafeFnPointer) => {
                 let src = self.read_immediate(src)?;
-                match dest.layout.ty.sty {
+                match dest.layout.ty.kind {
                     ty::FnPtr(_) => {
                         // No change to value
                         self.write_immediate(*src, dest)?;
@@ -65,7 +65,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
 
             Pointer(PointerCast::ClosureFnPointer(_)) => {
                 // The src operand does not matter, just its type
-                match src.layout.ty.sty {
+                match src.layout.ty.kind {
                     ty::Closure(def_id, substs) => {
                         // All reifications must be monomorphic, bail out otherwise.
                         if src.layout.ty.needs_subst() {
@@ -97,7 +97,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         use rustc::ty::TyKind::*;
         trace!("Casting {:?}: {:?} to {:?}", *src, src.layout.ty, dest_layout.ty);
 
-        match src.layout.ty.sty {
+        match src.layout.ty.kind {
             // Floating point
             Float(FloatTy::F32) =>
                 return Ok(self.cast_from_float(src.to_scalar()?.to_f32()?, dest_layout.ty)?.into()),
@@ -176,7 +176,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         };
         trace!("cast_from_int: {}, {}, {}", v, src_layout.ty, dest_layout.ty);
         use rustc::ty::TyKind::*;
-        match dest_layout.ty.sty {
+        match dest_layout.ty.kind {
             Int(_) | Uint(_) | RawPtr(_) => {
                 let v = self.truncate(v, dest_layout);
                 Ok(Scalar::from_uint(v, dest_layout.size))
@@ -214,7 +214,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
     where F: Float + Into<Scalar<M::PointerTag>> + FloatConvert<Single> + FloatConvert<Double>
     {
         use rustc::ty::TyKind::*;
-        match dest_ty.sty {
+        match dest_ty.kind {
             // float -> uint
             Uint(t) => {
                 let width = t.bit_width().unwrap_or_else(|| self.pointer_size().bits() as usize);
@@ -244,14 +244,14 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         src: OpTy<'tcx, M::PointerTag>,
         dest: PlaceTy<'tcx, M::PointerTag>,
         // The pointee types
-        sty: Ty<'tcx>,
-        dty: Ty<'tcx>,
+        source_ty: Ty<'tcx>,
+        dest_ty: Ty<'tcx>,
     ) -> InterpResult<'tcx> {
         // A<Struct> -> A<Trait> conversion
         let (src_pointee_ty, dest_pointee_ty) =
-            self.tcx.struct_lockstep_tails_erasing_lifetimes(sty, dty, self.param_env);
+            self.tcx.struct_lockstep_tails_erasing_lifetimes(source_ty, dest_ty, self.param_env);
 
-        match (&src_pointee_ty.sty, &dest_pointee_ty.sty) {
+        match (&src_pointee_ty.kind, &dest_pointee_ty.kind) {
             (&ty::Array(_, length), &ty::Slice(_)) => {
                 let ptr = self.read_immediate(src)?.to_scalar_ptr()?;
                 // u64 cast is from usize to u64, which is always good
@@ -287,7 +287,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         dest: PlaceTy<'tcx, M::PointerTag>,
     ) -> InterpResult<'tcx> {
         trace!("Unsizing {:?} into {:?}", src, dest);
-        match (&src.layout.ty.sty, &dest.layout.ty.sty) {
+        match (&src.layout.ty.kind, &dest.layout.ty.kind) {
             (&ty::Ref(_, s, _), &ty::Ref(_, d, _)) |
             (&ty::Ref(_, s, _), &ty::RawPtr(TypeAndMut { ty: d, .. })) |
             (&ty::RawPtr(TypeAndMut { ty: s, .. }),
diff --git a/src/librustc_mir/interpret/eval_context.rs b/src/librustc_mir/interpret/eval_context.rs
index 78996ed6939d8..fdf85260c3d96 100644
--- a/src/librustc_mir/interpret/eval_context.rs
+++ b/src/librustc_mir/interpret/eval_context.rs
@@ -387,7 +387,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         if !layout.is_unsized() {
             return Ok(Some((layout.size, layout.align.abi)));
         }
-        match layout.ty.sty {
+        match layout.ty.kind {
             ty::Adt(..) | ty::Tuple(..) => {
                 // First get the size of all statically known fields.
                 // Don't use type_of::sizing_type_of because that expects t to be sized,
diff --git a/src/librustc_mir/interpret/intern.rs b/src/librustc_mir/interpret/intern.rs
index 95647ce642c5b..ec06b6298e112 100644
--- a/src/librustc_mir/interpret/intern.rs
+++ b/src/librustc_mir/interpret/intern.rs
@@ -192,13 +192,13 @@ for
         // Handle Reference types, as these are the only relocations supported by const eval.
         // Raw pointers (and boxes) are handled by the `leftover_relocations` logic.
         let ty = mplace.layout.ty;
-        if let ty::Ref(_, referenced_ty, mutability) = ty.sty {
+        if let ty::Ref(_, referenced_ty, mutability) = ty.kind {
             let value = self.ecx.read_immediate(mplace.into())?;
             // Handle trait object vtables
             if let Ok(meta) = value.to_meta() {
                 if let ty::Dynamic(..) =
                     self.ecx.tcx.struct_tail_erasing_lifetimes(
-                        referenced_ty, self.ecx.param_env).sty
+                        referenced_ty, self.ecx.param_env).kind
                 {
                     if let Ok(vtable) = meta.unwrap().to_ptr() {
                         // explitly choose `Immutable` here, since vtables are immutable, even
@@ -228,7 +228,7 @@ for
                     // we statically prevent `&mut T` via `const_qualif` and double check this here
                     (InternMode::ConstBase, hir::Mutability::MutMutable) |
                     (InternMode::Const, hir::Mutability::MutMutable) => {
-                        match referenced_ty.sty {
+                        match referenced_ty.kind {
                             ty::Array(_, n)
                                 if n.eval_usize(self.ecx.tcx.tcx, self.ecx.param_env) == 0 => {}
                             ty::Slice(_)
diff --git a/src/librustc_mir/interpret/intrinsics/type_name.rs b/src/librustc_mir/interpret/intrinsics/type_name.rs
index 1e765a4ed982c..a6b3b4e0ff67d 100644
--- a/src/librustc_mir/interpret/intrinsics/type_name.rs
+++ b/src/librustc_mir/interpret/intrinsics/type_name.rs
@@ -32,7 +32,7 @@ impl<'tcx> Printer<'tcx> for AbsolutePathPrinter<'tcx> {
     }
 
     fn print_type(mut self, ty: Ty<'tcx>) -> Result<Self::Type, Self::Error> {
-        match ty.sty {
+        match ty.kind {
             // Types without identity.
             | ty::Bool
             | ty::Char
diff --git a/src/librustc_mir/interpret/operand.rs b/src/librustc_mir/interpret/operand.rs
index afaf9d7ed9d67..f5d1ec3eb7556 100644
--- a/src/librustc_mir/interpret/operand.rs
+++ b/src/librustc_mir/interpret/operand.rs
@@ -664,7 +664,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                     bits_discr
                 };
                 // Make sure we catch invalid discriminants
-                let index = match &rval.layout.ty.sty {
+                let index = match &rval.layout.ty.kind {
                     ty::Adt(adt, _) => adt
                         .discriminants(self.tcx.tcx)
                         .find(|(_, var)| var.val == real_discr),
diff --git a/src/librustc_mir/interpret/operator.rs b/src/librustc_mir/interpret/operator.rs
index 470cc9346ee21..176b084f22587 100644
--- a/src/librustc_mir/interpret/operator.rs
+++ b/src/librustc_mir/interpret/operator.rs
@@ -274,7 +274,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         trace!("Running binary op {:?}: {:?} ({:?}), {:?} ({:?})",
             bin_op, *left, left.layout.ty, *right, right.layout.ty);
 
-        match left.layout.ty.sty {
+        match left.layout.ty.kind {
             ty::Char => {
                 assert_eq!(left.layout.ty, right.layout.ty);
                 let left = left.to_scalar()?;
@@ -348,7 +348,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         let val = val.to_scalar()?;
         trace!("Running unary op {:?}: {:?} ({:?})", un_op, val, layout.ty);
 
-        match layout.ty.sty {
+        match layout.ty.kind {
             ty::Bool => {
                 let val = val.to_bool()?;
                 let res = match un_op {
diff --git a/src/librustc_mir/interpret/place.rs b/src/librustc_mir/interpret/place.rs
index c3660fb7a2e28..2f1b35757fe9c 100644
--- a/src/librustc_mir/interpret/place.rs
+++ b/src/librustc_mir/interpret/place.rs
@@ -193,7 +193,7 @@ impl<'tcx, Tag> MPlaceTy<'tcx, Tag> {
     pub(super) fn len(self, cx: &impl HasDataLayout) -> InterpResult<'tcx, u64> {
         if self.layout.is_unsized() {
             // We need to consult `meta` metadata
-            match self.layout.ty.sty {
+            match self.layout.ty.kind {
                 ty::Slice(..) | ty::Str =>
                     return self.mplace.meta.unwrap().to_usize(cx),
                 _ => bug!("len not supported on unsized type {:?}", self.layout.ty),
@@ -210,7 +210,7 @@ impl<'tcx, Tag> MPlaceTy<'tcx, Tag> {
 
     #[inline]
     pub(super) fn vtable(self) -> Scalar<Tag> {
-        match self.layout.ty.sty {
+        match self.layout.ty.kind {
             ty::Dynamic(..) => self.mplace.meta.unwrap(),
             _ => bug!("vtable not supported on type {:?}", self.layout.ty),
         }
@@ -459,7 +459,7 @@ where
 
         // Compute meta and new layout
         let inner_len = len - to - from;
-        let (meta, ty) = match base.layout.ty.sty {
+        let (meta, ty) = match base.layout.ty.kind {
             // It is not nice to match on the type, but that seems to be the only way to
             // implement this.
             ty::Array(inner, _) =>
diff --git a/src/librustc_mir/interpret/terminator.rs b/src/librustc_mir/interpret/terminator.rs
index 8666c937ce4c2..ef6b7d626e7a4 100644
--- a/src/librustc_mir/interpret/terminator.rs
+++ b/src/librustc_mir/interpret/terminator.rs
@@ -75,7 +75,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 };
 
                 let func = self.eval_operand(func, None)?;
-                let (fn_val, abi) = match func.layout.ty.sty {
+                let (fn_val, abi) = match func.layout.ty.kind {
                     ty::FnPtr(sig) => {
                         let caller_abi = sig.abi();
                         let fn_ptr = self.read_scalar(func)?.not_undef()?;
@@ -272,7 +272,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
                 {
                     let callee_abi = {
                         let instance_ty = instance.ty(*self.tcx);
-                        match instance_ty.sty {
+                        match instance_ty.kind {
                             ty::FnDef(..) =>
                                 instance_ty.fn_sig(*self.tcx).abi(),
                             ty::Closure(..) => Abi::RustCall,
@@ -479,7 +479,7 @@ impl<'mir, 'tcx, M: Machine<'mir, 'tcx>> InterpCx<'mir, 'tcx, M> {
         // implementation fail -- a problem shared by rustc.
         let place = self.force_allocation(place)?;
 
-        let (instance, place) = match place.layout.ty.sty {
+        let (instance, place) = match place.layout.ty.kind {
             ty::Dynamic(..) => {
                 // Dropping a trait object.
                 self.unpack_dyn_trait(place)?
diff --git a/src/librustc_mir/interpret/validity.rs b/src/librustc_mir/interpret/validity.rs
index 3e14ba3efcc58..e6fa833c7b25b 100644
--- a/src/librustc_mir/interpret/validity.rs
+++ b/src/librustc_mir/interpret/validity.rs
@@ -188,7 +188,7 @@ impl<'rt, 'mir, 'tcx, M: Machine<'mir, 'tcx>> ValidityVisitor<'rt, 'mir, 'tcx, M
         layout: TyLayout<'tcx>,
         field: usize,
     ) -> PathElem {
-        match layout.ty.sty {
+        match layout.ty.kind {
             // generators and closures.
             ty::Closure(def_id, _) | ty::Generator(def_id, _, _) => {
                 let mut name = None;
@@ -263,7 +263,7 @@ impl<'rt, 'mir, 'tcx, M: Machine<'mir, 'tcx>> ValidityVisitor<'rt, 'mir, 'tcx, M
         pointee: TyLayout<'tcx>,
     ) -> InterpResult<'tcx> {
         let tail = self.ecx.tcx.struct_tail_erasing_lifetimes(pointee.ty, self.ecx.param_env);
-        match tail.sty {
+        match tail.kind {
             ty::Dynamic(..) => {
                 let vtable = meta.unwrap();
                 try_validation!(
@@ -327,7 +327,7 @@ impl<'rt, 'mir, 'tcx, M: Machine<'mir, 'tcx>> ValueVisitor<'mir, 'tcx, M>
         variant_id: VariantIdx,
         new_op: OpTy<'tcx, M::PointerTag>
     ) -> InterpResult<'tcx> {
-        let name = match old_op.layout.ty.sty {
+        let name = match old_op.layout.ty.kind {
             ty::Adt(adt, _) => PathElem::Variant(adt.variants[variant_id].ident.name),
             // Generators also have variants
             ty::Generator(..) => PathElem::GeneratorState(variant_id),
@@ -362,7 +362,7 @@ impl<'rt, 'mir, 'tcx, M: Machine<'mir, 'tcx>> ValueVisitor<'mir, 'tcx, M>
         let value = self.ecx.read_immediate(value)?;
         // Go over all the primitive types
         let ty = value.layout.ty;
-        match ty.sty {
+        match ty.kind {
             ty::Bool => {
                 let value = value.to_scalar_or_undef();
                 try_validation!(value.to_bool(),
@@ -581,7 +581,7 @@ impl<'rt, 'mir, 'tcx, M: Machine<'mir, 'tcx>> ValueVisitor<'mir, 'tcx, M>
         op: OpTy<'tcx, M::PointerTag>,
         fields: impl Iterator<Item=InterpResult<'tcx, Self::V>>,
     ) -> InterpResult<'tcx> {
-        match op.layout.ty.sty {
+        match op.layout.ty.kind {
             ty::Str => {
                 let mplace = op.assert_mem_place(); // strings are never immediate
                 try_validation!(self.ecx.read_str(mplace),
@@ -590,7 +590,7 @@ impl<'rt, 'mir, 'tcx, M: Machine<'mir, 'tcx>> ValueVisitor<'mir, 'tcx, M>
             ty::Array(tys, ..) | ty::Slice(tys) if {
                 // This optimization applies only for integer and floating point types
                 // (i.e., types that can hold arbitrary bytes).
-                match tys.sty {
+                match tys.kind {
                     ty::Int(..) | ty::Uint(..) | ty::Float(..) => true,
                     _ => false,
                 }
diff --git a/src/librustc_mir/interpret/visitor.rs b/src/librustc_mir/interpret/visitor.rs
index 91fbd307db121..427f94f4fbb02 100644
--- a/src/librustc_mir/interpret/visitor.rs
+++ b/src/librustc_mir/interpret/visitor.rs
@@ -239,7 +239,7 @@ macro_rules! make_value_visitor {
 
                 // Even for single variants, we might be able to get a more refined type:
                 // If it is a trait object, switch to the actual type that was used to create it.
-                match v.layout().ty.sty {
+                match v.layout().ty.kind {
                     ty::Dynamic(..) => {
                         // immediate trait objects are not a thing
                         let dest = v.to_op(self.ecx())?.assert_mem_place();
diff --git a/src/librustc_mir/lints.rs b/src/librustc_mir/lints.rs
index 8c815a51b5d65..4f978051eaccd 100644
--- a/src/librustc_mir/lints.rs
+++ b/src/librustc_mir/lints.rs
@@ -86,7 +86,7 @@ fn check_fn_for_unconditional_recursion(
                 TerminatorKind::Call { ref func, .. } => {
                     let func_ty = func.ty(body, tcx);
 
-                    if let ty::FnDef(fn_def_id, substs) = func_ty.sty {
+                    if let ty::FnDef(fn_def_id, substs) = func_ty.kind {
                         let (call_fn_id, call_substs) =
                             if let Some(instance) = Instance::resolve(tcx,
                                                                         param_env,
diff --git a/src/librustc_mir/monomorphize/collector.rs b/src/librustc_mir/monomorphize/collector.rs
index 1f7efebfda819..d7a837e7ede66 100644
--- a/src/librustc_mir/monomorphize/collector.rs
+++ b/src/librustc_mir/monomorphize/collector.rs
@@ -578,7 +578,7 @@ impl<'a, 'tcx> MirVisitor<'tcx> for MirNeighborCollector<'a, 'tcx> {
                     ty::ParamEnv::reveal_all(),
                     &source_ty,
                 );
-                match source_ty.sty {
+                match source_ty.kind {
                     ty::Closure(def_id, substs) => {
                         let instance = Instance::resolve_closure(
                             self.tcx, def_id, substs, ty::ClosureKind::FnOnce);
@@ -712,7 +712,7 @@ fn visit_fn_use<'tcx>(
     is_direct_call: bool,
     output: &mut Vec<MonoItem<'tcx>>,
 ) {
-    if let ty::FnDef(def_id, substs) = ty.sty {
+    if let ty::FnDef(def_id, substs) = ty.kind {
         let instance = ty::Instance::resolve(tcx,
                                              ty::ParamEnv::reveal_all(),
                                              def_id,
@@ -874,7 +874,7 @@ fn find_vtable_types_for_unsizing<'tcx>(
                 return false;
             }
             let tail = tcx.struct_tail_erasing_lifetimes(ty, param_env);
-            match tail.sty {
+            match tail.kind {
                 ty::Foreign(..) => false,
                 ty::Str | ty::Slice(..) | ty::Dynamic(..) => true,
                 _ => bug!("unexpected unsized tail: {:?}", tail),
@@ -887,7 +887,7 @@ fn find_vtable_types_for_unsizing<'tcx>(
         }
     };
 
-    match (&source_ty.sty, &target_ty.sty) {
+    match (&source_ty.kind, &target_ty.kind) {
         (&ty::Ref(_, a, _),
          &ty::Ref(_, b, _)) |
         (&ty::Ref(_, a, _),
@@ -945,7 +945,7 @@ fn create_mono_items_for_vtable_methods<'tcx>(
     assert!(!trait_ty.needs_subst() && !trait_ty.has_escaping_bound_vars() &&
             !impl_ty.needs_subst() && !impl_ty.has_escaping_bound_vars());
 
-    if let ty::Dynamic(ref trait_ty, ..) = trait_ty.sty {
+    if let ty::Dynamic(ref trait_ty, ..) = trait_ty.kind {
         if let Some(principal) = trait_ty.principal() {
             let poly_trait_ref = principal.with_self_ty(tcx, impl_ty);
             assert!(!poly_trait_ref.has_escaping_bound_vars());
diff --git a/src/librustc_mir/shim.rs b/src/librustc_mir/shim.rs
index 6daca5e261431..f5eb07882fe32 100644
--- a/src/librustc_mir/shim.rs
+++ b/src/librustc_mir/shim.rs
@@ -167,7 +167,7 @@ fn build_drop_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, ty: Option<Ty<'tcx>>)
     debug!("build_drop_shim(def_id={:?}, ty={:?})", def_id, ty);
 
     // Check if this is a generator, if so, return the drop glue for it
-    if let Some(&ty::TyS { sty: ty::Generator(gen_def_id, substs, _), .. }) = ty {
+    if let Some(&ty::TyS { kind: ty::Generator(gen_def_id, substs, _), .. }) = ty {
         let body = &**tcx.optimized_mir(gen_def_id).generator_drop.as_ref().unwrap();
         return body.subst(tcx, substs.substs);
     }
@@ -311,7 +311,7 @@ fn build_clone_shim<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId, self_ty: Ty<'tcx>) -
     let dest = Place::return_place();
     let src = Place::from(Local::new(1+0)).deref();
 
-    match self_ty.sty {
+    match self_ty.kind {
         _ if is_copy => builder.copy_shim(),
         ty::Array(ty, len) => {
             let len = len.eval_usize(tcx, param_env);
@@ -857,7 +857,7 @@ pub fn build_adt_ctor(tcx: TyCtxt<'_>, ctor_id: DefId) -> &Body<'_> {
         .expect("LBR in ADT constructor signature");
     let sig = tcx.normalize_erasing_regions(param_env, sig);
 
-    let (adt_def, substs) = match sig.output().sty {
+    let (adt_def, substs) = match sig.output().kind {
         ty::Adt(adt_def, substs) => (adt_def, substs),
         _ => bug!("unexpected type for ADT ctor {:?}", sig.output())
     };
diff --git a/src/librustc_mir/transform/add_retag.rs b/src/librustc_mir/transform/add_retag.rs
index 833c8b1646bb6..b56a1b263fd6a 100644
--- a/src/librustc_mir/transform/add_retag.rs
+++ b/src/librustc_mir/transform/add_retag.rs
@@ -37,7 +37,7 @@ fn is_stable(
 
 /// Determine whether this type may be a reference (or box), and thus needs retagging.
 fn may_be_reference<'tcx>(ty: Ty<'tcx>) -> bool {
-    match ty.sty {
+    match ty.kind {
         // Primitive types that are not references
         ty::Bool | ty::Char |
         ty::Float(_) | ty::Int(_) | ty::Uint(_) |
diff --git a/src/librustc_mir/transform/check_unsafety.rs b/src/librustc_mir/transform/check_unsafety.rs
index 61e32ca8de522..faec8c7cbe400 100644
--- a/src/librustc_mir/transform/check_unsafety.rs
+++ b/src/librustc_mir/transform/check_unsafety.rs
@@ -182,7 +182,7 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
             // result of a comparison of addresses would differ between runtime and compile-time.
             Rvalue::BinaryOp(_, ref lhs, _)
             if self.const_context && self.tcx.features().const_compare_raw_pointers => {
-                if let ty::RawPtr(_) | ty::FnPtr(..) = lhs.ty(self.body, self.tcx).sty {
+                if let ty::RawPtr(_) | ty::FnPtr(..) = lhs.ty(self.body, self.tcx).kind {
                     self.register_violations(&[UnsafetyViolation {
                         source_info: self.source_info,
                         description: InternedString::intern("pointer operation"),
@@ -274,7 +274,7 @@ impl<'a, 'tcx> Visitor<'tcx> for UnsafetyChecker<'a, 'tcx> {
                 }
             }
             let base_ty = Place::ty_from(&place.base, proj_base, self.body, self.tcx).ty;
-            match base_ty.sty {
+            match base_ty.kind {
                 ty::RawPtr(..) => {
                     self.require_unsafe("dereference of raw pointer",
                         "raw pointers may be NULL, dangling or unaligned; they can violate \
@@ -416,7 +416,7 @@ impl<'a, 'tcx> UnsafetyChecker<'a, 'tcx> {
                     let ty =
                         Place::ty_from(&place.base, proj_base, &self.body.local_decls, self.tcx)
                             .ty;
-                    match ty.sty {
+                    match ty.kind {
                         ty::Adt(def, _) => match self.tcx.layout_scalar_valid_range(def.did) {
                             (Bound::Unbounded, Bound::Unbounded) => {},
                             _ => {
diff --git a/src/librustc_mir/transform/const_prop.rs b/src/librustc_mir/transform/const_prop.rs
index 614d5d2a4a2fb..857757ada53b7 100644
--- a/src/librustc_mir/transform/const_prop.rs
+++ b/src/librustc_mir/transform/const_prop.rs
@@ -372,7 +372,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
                 let place = self.eval_place(&place, source_info)?;
                 let mplace = place.try_as_mplace().ok()?;
 
-                if let ty::Slice(_) = mplace.layout.ty.sty {
+                if let ty::Slice(_) = mplace.layout.ty.kind {
                     let len = mplace.meta.unwrap().to_usize(&self.ecx).unwrap();
 
                     Some(ImmTy::from_uint(
@@ -380,7 +380,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
                         self.tcx.layout_of(self.param_env.and(self.tcx.types.usize)).ok()?,
                     ).into())
                 } else {
-                    trace!("not slice: {:?}", mplace.layout.ty.sty);
+                    trace!("not slice: {:?}", mplace.layout.ty.kind);
                     None
                 }
             },
@@ -552,7 +552,7 @@ impl<'mir, 'tcx> ConstPropagator<'mir, 'tcx> {
                     ScalarMaybeUndef::Scalar(one),
                     ScalarMaybeUndef::Scalar(two)
                 ) => {
-                    let ty = &value.layout.ty.sty;
+                    let ty = &value.layout.ty.kind;
                     if let ty::Tuple(substs) = ty {
                         *rval = Rvalue::Aggregate(
                             Box::new(AggregateKind::Tuple),
diff --git a/src/librustc_mir/transform/generator.rs b/src/librustc_mir/transform/generator.rs
index caf588af851dd..2b66e602370cc 100644
--- a/src/librustc_mir/transform/generator.rs
+++ b/src/librustc_mir/transform/generator.rs
@@ -711,7 +711,7 @@ fn compute_layout<'tcx>(
     // Erase regions from the types passed in from typeck so we can compare them with
     // MIR types
     let allowed_upvars = tcx.erase_regions(upvars);
-    let allowed = match interior.sty {
+    let allowed = match interior.kind {
         ty::GeneratorWitness(s) => tcx.erase_late_bound_regions(&s),
         _ => bug!(),
     };
@@ -1124,7 +1124,7 @@ impl<'tcx> MirPass<'tcx> for StateTransform {
         let gen_ty = body.local_decls.raw[1].ty;
 
         // Get the interior types and substs which typeck computed
-        let (upvars, interior, discr_ty, movable) = match gen_ty.sty {
+        let (upvars, interior, discr_ty, movable) = match gen_ty.kind {
             ty::Generator(_, substs, movability) => {
                 (substs.upvar_tys(def_id, tcx).collect(),
                  substs.witness(def_id, tcx),
diff --git a/src/librustc_mir/transform/inline.rs b/src/librustc_mir/transform/inline.rs
index 5ad026dc143c9..7f56c6f7986aa 100644
--- a/src/librustc_mir/transform/inline.rs
+++ b/src/librustc_mir/transform/inline.rs
@@ -177,7 +177,7 @@ impl Inliner<'tcx> {
         // Only consider direct calls to functions
         let terminator = bb_data.terminator();
         if let TerminatorKind::Call { func: ref op, .. } = terminator.kind {
-            if let ty::FnDef(callee_def_id, substs) = op.ty(caller_body, self.tcx).sty {
+            if let ty::FnDef(callee_def_id, substs) = op.ty(caller_body, self.tcx).kind {
                 let instance = Instance::resolve(self.tcx,
                                                  param_env,
                                                  callee_def_id,
@@ -328,7 +328,7 @@ impl Inliner<'tcx> {
                 }
 
                 TerminatorKind::Call {func: Operand::Constant(ref f), .. } => {
-                    if let ty::FnDef(def_id, _) = f.literal.ty.sty {
+                    if let ty::FnDef(def_id, _) = f.literal.ty.kind {
                         // Don't give intrinsics the extra penalty for calls
                         let f = tcx.fn_sig(def_id);
                         if f.abi() == Abi::RustIntrinsic || f.abi() == Abi::PlatformIntrinsic {
@@ -546,7 +546,7 @@ impl Inliner<'tcx> {
             assert!(args.next().is_none());
 
             let tuple = Place::from(tuple);
-            let tuple_tys = if let ty::Tuple(s) = tuple.ty(caller_body, tcx).ty.sty {
+            let tuple_tys = if let ty::Tuple(s) = tuple.ty(caller_body, tcx).ty.kind {
                 s
             } else {
                 bug!("Closure arguments are not passed as a tuple");
diff --git a/src/librustc_mir/transform/instcombine.rs b/src/librustc_mir/transform/instcombine.rs
index 0e04e63af4522..6b609e25ec042 100644
--- a/src/librustc_mir/transform/instcombine.rs
+++ b/src/librustc_mir/transform/instcombine.rs
@@ -102,7 +102,7 @@ impl Visitor<'tcx> for OptimizationFinder<'b, 'tcx> {
 
         if let Rvalue::Len(ref place) = *rvalue {
             let place_ty = place.ty(&self.body.local_decls, self.tcx).ty;
-            if let ty::Array(_, len) = place_ty.sty {
+            if let ty::Array(_, len) = place_ty.kind {
                 let span = self.body.source_info(location).span;
                 let constant = Constant { span, literal: len, user_ty: None };
                 self.optimizations.arrays_lengths.insert(location, constant);
diff --git a/src/librustc_mir/transform/qualify_consts.rs b/src/librustc_mir/transform/qualify_consts.rs
index 8a6dcd1d2b476..abe2d2f4a549e 100644
--- a/src/librustc_mir/transform/qualify_consts.rs
+++ b/src/librustc_mir/transform/qualify_consts.rs
@@ -294,7 +294,7 @@ trait Qualif {
                 if let box [proj_base @ .., elem] = &place.projection {
                     if ProjectionElem::Deref == *elem {
                         let base_ty = Place::ty_from(&place.base, proj_base, cx.body, cx.tcx).ty;
-                        if let ty::Ref(..) = base_ty.sty {
+                        if let ty::Ref(..) = base_ty.kind {
                             return Self::in_place(cx, PlaceRef {
                                 base: &place.base,
                                 projection: proj_base,
@@ -365,11 +365,11 @@ impl Qualif for HasMutInterior {
                     // is allowed right now, and only in functions.
                     if cx.mode == Mode::StaticMut {
                         // Inside a `static mut`, &mut [...] is also allowed.
-                        match ty.sty {
+                        match ty.kind {
                             ty::Array(..) | ty::Slice(_) => {}
                             _ => return true,
                         }
-                    } else if let ty::Array(_, len) = ty.sty {
+                    } else if let ty::Array(_, len) = ty.kind {
                         // FIXME(eddyb) the `cx.mode == Mode::NonConstFn` condition
                         // seems unnecessary, given that this is merely a ZST.
                         match len.try_eval_usize(cx.tcx, cx.param_env) {
@@ -500,7 +500,7 @@ impl Qualif for IsNotPromotable {
             }
 
             Rvalue::BinaryOp(op, ref lhs, _) if cx.mode == Mode::NonConstFn => {
-                if let ty::RawPtr(_) | ty::FnPtr(..) = lhs.ty(cx.body, cx.tcx).sty {
+                if let ty::RawPtr(_) | ty::FnPtr(..) = lhs.ty(cx.body, cx.tcx).kind {
                     assert!(op == BinOp::Eq || op == BinOp::Ne ||
                             op == BinOp::Le || op == BinOp::Lt ||
                             op == BinOp::Ge || op == BinOp::Gt ||
@@ -526,7 +526,7 @@ impl Qualif for IsNotPromotable {
         _return_ty: Ty<'tcx>,
     ) -> bool {
         let fn_ty = callee.ty(cx.body, cx.tcx);
-        match fn_ty.sty {
+        match fn_ty.kind {
             ty::FnDef(def_id, _) => {
                 match cx.tcx.fn_sig(def_id).abi() {
                     Abi::RustIntrinsic |
@@ -599,7 +599,7 @@ impl Qualif for IsNotImplicitlyPromotable {
         _return_ty: Ty<'tcx>,
     ) -> bool {
         if cx.mode == Mode::NonConstFn {
-            if let ty::FnDef(def_id, _) = callee.ty(cx.body, cx.tcx).sty {
+            if let ty::FnDef(def_id, _) = callee.ty(cx.body, cx.tcx).kind {
                 // Never promote runtime `const fn` calls of
                 // functions without `#[rustc_promotable]`.
                 if !cx.tcx.is_promotable_const_fn(def_id) {
@@ -1108,7 +1108,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Checker<'a, 'tcx> {
                     match self.mode {
                         Mode::NonConstFn => {},
                         _ => {
-                            if let ty::RawPtr(_) = base_ty.sty {
+                            if let ty::RawPtr(_) = base_ty.kind {
                                 if !self.tcx.features().const_raw_ptr_deref {
                                     emit_feature_err(
                                         &self.tcx.sess.parse_sess, sym::const_raw_ptr_deref,
@@ -1188,7 +1188,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Checker<'a, 'tcx> {
             if let box [proj_base @ .., elem] = &place.projection {
                 if *elem == ProjectionElem::Deref {
                     let base_ty = Place::ty_from(&place.base, proj_base, self.body, self.tcx).ty;
-                    if let ty::Ref(..) = base_ty.sty {
+                    if let ty::Ref(..) = base_ty.kind {
                         reborrow_place = Some(proj_base);
                     }
                 }
@@ -1257,7 +1257,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Checker<'a, 'tcx> {
             }
 
             Rvalue::BinaryOp(op, ref lhs, _) => {
-                if let ty::RawPtr(_) | ty::FnPtr(..) = lhs.ty(self.body, self.tcx).sty {
+                if let ty::RawPtr(_) | ty::FnPtr(..) = lhs.ty(self.body, self.tcx).kind {
                     assert!(op == BinOp::Eq || op == BinOp::Ne ||
                             op == BinOp::Le || op == BinOp::Lt ||
                             op == BinOp::Ge || op == BinOp::Gt ||
@@ -1316,7 +1316,7 @@ impl<'a, 'tcx> Visitor<'tcx> for Checker<'a, 'tcx> {
             let fn_ty = func.ty(self.body, self.tcx);
             let mut callee_def_id = None;
             let mut is_shuffle = false;
-            match fn_ty.sty {
+            match fn_ty.kind {
                 ty::FnDef(def_id, _) => {
                     callee_def_id = Some(def_id);
                     match self.tcx.fn_sig(def_id).abi() {
diff --git a/src/librustc_mir/transform/qualify_min_const_fn.rs b/src/librustc_mir/transform/qualify_min_const_fn.rs
index be83c823d4242..cf0ee1bf09222 100644
--- a/src/librustc_mir/transform/qualify_min_const_fn.rs
+++ b/src/librustc_mir/transform/qualify_min_const_fn.rs
@@ -32,7 +32,7 @@ pub fn is_min_const_fn(tcx: TyCtxt<'tcx>, def_id: DefId, body: &'a Body<'tcx>) -
                     if Some(pred.def_id()) == tcx.lang_items().sized_trait() {
                         continue;
                     }
-                    match pred.skip_binder().self_ty().sty {
+                    match pred.skip_binder().self_ty().kind {
                         ty::Param(ref p) => {
                             let generics = tcx.generics_of(current);
                             let def = generics.type_param(p, tcx);
@@ -79,7 +79,7 @@ pub fn is_min_const_fn(tcx: TyCtxt<'tcx>, def_id: DefId, body: &'a Body<'tcx>) -
 
 fn check_ty(tcx: TyCtxt<'tcx>, ty: Ty<'tcx>, span: Span, fn_def_id: DefId) -> McfResult {
     for ty in ty.walk() {
-        match ty.sty {
+        match ty.kind {
             ty::Ref(_, _, hir::Mutability::MutMutable) => return Err((
                 span,
                 "mutable references in const fn are unstable".into(),
@@ -342,7 +342,7 @@ fn check_terminator(
             cleanup: _,
         } => {
             let fn_ty = func.ty(body, tcx);
-            if let ty::FnDef(def_id, _) = fn_ty.sty {
+            if let ty::FnDef(def_id, _) = fn_ty.kind {
 
                 // some intrinsics are waved through if called inside the
                 // standard library. Users never need to call them directly
diff --git a/src/librustc_mir/transform/rustc_peek.rs b/src/librustc_mir/transform/rustc_peek.rs
index 68fa082d29407..539645d0227f4 100644
--- a/src/librustc_mir/transform/rustc_peek.rs
+++ b/src/librustc_mir/transform/rustc_peek.rs
@@ -224,7 +224,7 @@ fn is_rustc_peek<'a, 'tcx>(
     if let Some(mir::Terminator { ref kind, source_info, .. }) = *terminator {
         if let mir::TerminatorKind::Call { func: ref oper, ref args, .. } = *kind {
             if let mir::Operand::Constant(ref func) = *oper {
-                if let ty::FnDef(def_id, _) = func.literal.ty.sty {
+                if let ty::FnDef(def_id, _) = func.literal.ty.kind {
                     let abi = tcx.fn_sig(def_id).abi();
                     let name = tcx.item_name(def_id);
                     if abi == Abi::RustIntrinsic && name == sym::rustc_peek {
diff --git a/src/librustc_mir/transform/uniform_array_move_out.rs b/src/librustc_mir/transform/uniform_array_move_out.rs
index 34ad5cb5dc787..eb61cd2f657a2 100644
--- a/src/librustc_mir/transform/uniform_array_move_out.rs
+++ b/src/librustc_mir/transform/uniform_array_move_out.rs
@@ -69,7 +69,7 @@ impl<'a, 'tcx> Visitor<'tcx> for UniformArrayMoveOutVisitor<'a, 'tcx> {
                 } else {
                     let place_ty =
                         Place::ty_from(&src_place.base, proj_base, self.body, self.tcx).ty;
-                    if let ty::Array(item_ty, const_size) = place_ty.sty {
+                    if let ty::Array(item_ty, const_size) = place_ty.kind {
                         if let Some(size) = const_size.try_eval_usize(self.tcx, self.param_env) {
                             assert!(size <= u32::max_value() as u64,
                                     "uniform array move out doesn't supported
@@ -224,7 +224,7 @@ impl<'tcx> MirPass<'tcx> for RestoreSubsliceArrayMoveOut {
                         let opt_size = opt_src_place.and_then(|src_place| {
                             let src_ty =
                                 Place::ty_from(src_place.base, src_place.projection, body, tcx).ty;
-                            if let ty::Array(_, ref size_o) = src_ty.sty {
+                            if let ty::Array(_, ref size_o) = src_ty.kind {
                                 size_o.try_eval_usize(tcx, param_env)
                             } else {
                                 None
diff --git a/src/librustc_mir/util/alignment.rs b/src/librustc_mir/util/alignment.rs
index a75c1af04f047..1bad85ec42d08 100644
--- a/src/librustc_mir/util/alignment.rs
+++ b/src/librustc_mir/util/alignment.rs
@@ -47,7 +47,7 @@ where
             ProjectionElem::Deref => break,
             ProjectionElem::Field(..) => {
                 let ty = Place::ty_from(&place.base, proj_base, local_decls, tcx).ty;
-                match ty.sty {
+                match ty.kind {
                     ty::Adt(def, _) if def.repr.packed() => {
                         return true
                     }
diff --git a/src/librustc_mir/util/borrowck_errors.rs b/src/librustc_mir/util/borrowck_errors.rs
index cf9ef55c17b34..96ba829358280 100644
--- a/src/librustc_mir/util/borrowck_errors.rs
+++ b/src/librustc_mir/util/borrowck_errors.rs
@@ -324,7 +324,7 @@ impl<'cx, 'tcx> crate::borrow_check::MirBorrowckCtxt<'cx, 'tcx> {
         ty: Ty<'_>,
         is_index: Option<bool>,
     ) -> DiagnosticBuilder<'cx> {
-        let type_name = match (&ty.sty, is_index) {
+        let type_name = match (&ty.kind, is_index) {
             (&ty::Array(_, _), Some(true)) | (&ty::Array(_, _), None) => "array",
             (&ty::Slice(_), _) => "slice",
             _ => span_bug!(move_from_span, "this path should not cause illegal move"),
diff --git a/src/librustc_mir/util/elaborate_drops.rs b/src/librustc_mir/util/elaborate_drops.rs
index 52ad97bbde1d7..e1015edfa8eec 100644
--- a/src/librustc_mir/util/elaborate_drops.rs
+++ b/src/librustc_mir/util/elaborate_drops.rs
@@ -786,7 +786,7 @@ where
     /// ADT, both in the success case or if one of the destructors fail.
     fn open_drop(&mut self) -> BasicBlock {
         let ty = self.place_ty(self.place);
-        match ty.sty {
+        match ty.kind {
             ty::Closure(def_id, substs) => {
                 let tys : Vec<_> = substs.upvar_tys(def_id, self.tcx()).collect();
                 self.open_drop_for_tuple(&tys)
diff --git a/src/librustc_passes/rvalue_promotion.rs b/src/librustc_passes/rvalue_promotion.rs
index 12978cd117b52..d4c3dc917e5e9 100644
--- a/src/librustc_passes/rvalue_promotion.rs
+++ b/src/librustc_passes/rvalue_promotion.rs
@@ -273,7 +273,7 @@ fn check_expr_kind<'a, 'tcx>(
     v: &mut CheckCrateVisitor<'a, 'tcx>,
     e: &'tcx hir::Expr, node_ty: Ty<'tcx>) -> Promotability {
 
-    let ty_result = match node_ty.sty {
+    let ty_result = match node_ty.kind {
         ty::Adt(def, _) if def.has_dtor(v.tcx) => {
             NotPromotable
         }
@@ -298,7 +298,7 @@ fn check_expr_kind<'a, 'tcx>(
             if v.tables.is_method_call(e) {
                 return NotPromotable;
             }
-            match v.tables.node_type(lhs.hir_id).sty {
+            match v.tables.node_type(lhs.hir_id).kind {
                 ty::RawPtr(_) | ty::FnPtr(..) => {
                     assert!(op.node == hir::BinOpKind::Eq || op.node == hir::BinOpKind::Ne ||
                             op.node == hir::BinOpKind::Le || op.node == hir::BinOpKind::Lt ||
@@ -427,7 +427,7 @@ fn check_expr_kind<'a, 'tcx>(
             if let Some(ref expr) = *option_expr {
                 struct_result &= v.check_expr(&expr);
             }
-            if let ty::Adt(adt, ..) = v.tables.expr_ty(e).sty {
+            if let ty::Adt(adt, ..) = v.tables.expr_ty(e).kind {
                 // unsafe_cell_type doesn't necessarily exist with no_core
                 if Some(adt.did) == v.tcx.lang_items().unsafe_cell_type() {
                     return NotPromotable;
diff --git a/src/librustc_privacy/lib.rs b/src/librustc_privacy/lib.rs
index 1e61f78c357df..d7f5fdeb00c52 100644
--- a/src/librustc_privacy/lib.rs
+++ b/src/librustc_privacy/lib.rs
@@ -129,7 +129,7 @@ where
     fn visit_ty(&mut self, ty: Ty<'tcx>) -> bool {
         let tcx = self.def_id_visitor.tcx();
         // InternalSubsts are not visited here because they are visited below in `super_visit_with`.
-        match ty.sty {
+        match ty.kind {
             ty::Adt(&ty::AdtDef { did: def_id, .. }, ..) |
             ty::Foreign(def_id) |
             ty::FnDef(def_id, ..) |
@@ -144,7 +144,7 @@ where
                 // Default type visitor doesn't visit signatures of fn types.
                 // Something like `fn() -> Priv {my_func}` is considered a private type even if
                 // `my_func` is public, so we need to visit signatures.
-                if let ty::FnDef(..) = ty.sty {
+                if let ty::FnDef(..) = ty.kind {
                     if tcx.fn_sig(def_id).visit_with(self) {
                         return true;
                     }
diff --git a/src/librustc_save_analysis/lib.rs b/src/librustc_save_analysis/lib.rs
index 055ccf6c2c4f8..7b1a6a9765b80 100644
--- a/src/librustc_save_analysis/lib.rs
+++ b/src/librustc_save_analysis/lib.rs
@@ -515,7 +515,7 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
         let expr_hir_id = self.tcx.hir().node_to_hir_id(expr.id);
         let hir_node = self.tcx.hir().expect_expr(expr_hir_id);
         let ty = self.tables.expr_ty_adjusted_opt(&hir_node);
-        if ty.is_none() || ty.unwrap().sty == ty::Error {
+        if ty.is_none() || ty.unwrap().kind == ty::Error {
             return None;
         }
         match expr.node {
@@ -532,7 +532,7 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
                         return None;
                     }
                 };
-                match self.tables.expr_ty_adjusted(&hir_node).sty {
+                match self.tables.expr_ty_adjusted(&hir_node).kind {
                     ty::Adt(def, _) if !def.is_enum() => {
                         let variant = &def.non_enum_variant();
                         let index = self.tcx.find_field_index(ident, variant).unwrap();
@@ -552,7 +552,7 @@ impl<'l, 'tcx> SaveContext<'l, 'tcx> {
                 }
             }
             ast::ExprKind::Struct(ref path, ..) => {
-                match self.tables.expr_ty_adjusted(&hir_node).sty {
+                match self.tables.expr_ty_adjusted(&hir_node).kind {
                     ty::Adt(def, _) if !def.is_enum() => {
                         let sub_span = path.segments.last().unwrap().ident.span;
                         filter!(self.span_utils, sub_span);
diff --git a/src/librustc_traits/chalk_context/mod.rs b/src/librustc_traits/chalk_context/mod.rs
index 5c23ad4a4edfb..fe66b1932d5e8 100644
--- a/src/librustc_traits/chalk_context/mod.rs
+++ b/src/librustc_traits/chalk_context/mod.rs
@@ -278,7 +278,7 @@ impl context::ContextOps<ChalkArenas<'tcx>> for ChalkContext<'tcx> {
                     }
                     _ => false,
                 },
-                UnpackedKind::Type(ty) => match ty.sty {
+                UnpackedKind::Type(ty) => match ty.kind {
                     ty::Bound(debruijn, bound_ty) => {
                         debug_assert_eq!(debruijn, ty::INNERMOST);
                         cvar == bound_ty.var
diff --git a/src/librustc_traits/chalk_context/program_clauses/builtin.rs b/src/librustc_traits/chalk_context/program_clauses/builtin.rs
index 71e18d2b6f949..cc5ca3d92c9c1 100644
--- a/src/librustc_traits/chalk_context/program_clauses/builtin.rs
+++ b/src/librustc_traits/chalk_context/program_clauses/builtin.rs
@@ -49,7 +49,7 @@ crate fn assemble_builtin_unsize_impls<'tcx>(
     target: Ty<'tcx>,
     clauses: &mut Vec<Clause<'tcx>>,
 ) {
-    match (&source.sty, &target.sty) {
+    match (&source.kind, &target.kind) {
         (ty::Dynamic(data_a, ..), ty::Dynamic(data_b, ..)) => {
             if data_a.principal_def_id() != data_b.principal_def_id()
                 || data_b.auto_traits().any(|b| data_a.auto_traits().all(|a| a != b))
@@ -130,7 +130,7 @@ crate fn assemble_builtin_sized_impls<'tcx>(
         clauses.push(Clause::ForAll(ty::Binder::bind(clause)));
     };
 
-    match &ty.sty {
+    match &ty.kind {
         // Non parametric primitive types.
         ty::Bool |
         ty::Char |
@@ -234,7 +234,7 @@ crate fn assemble_builtin_copy_clone_impls<'tcx>(
         clauses.push(Clause::ForAll(ty::Binder::bind(clause)));
     };
 
-    match &ty.sty {
+    match &ty.kind {
         // Implementations provided in libcore.
         ty::Bool |
         ty::Char |
@@ -264,7 +264,7 @@ crate fn assemble_builtin_copy_clone_impls<'tcx>(
         }
         &ty::Closure(def_id, ..) => {
             let closure_ty = generic_types::closure(tcx, def_id);
-            let upvar_tys: Vec<_> = match &closure_ty.sty {
+            let upvar_tys: Vec<_> = match &closure_ty.kind {
                 ty::Closure(_, substs) => {
                     substs.upvar_tys(def_id, tcx).map(|ty| Kind::from(ty)).collect()
                 },
diff --git a/src/librustc_traits/chalk_context/program_clauses/mod.rs b/src/librustc_traits/chalk_context/program_clauses/mod.rs
index a49ca400f5a21..1b6a5902be69b 100644
--- a/src/librustc_traits/chalk_context/program_clauses/mod.rs
+++ b/src/librustc_traits/chalk_context/program_clauses/mod.rs
@@ -176,7 +176,7 @@ impl ChalkInferenceContext<'cx, 'tcx> {
                 //   associated type (rule `WellFormed-AssocTy`)
                 // * custom rules for built-in types
                 // * the type definition otherwise (rule `WellFormed-Type`)
-                let clauses = match ty.sty {
+                let clauses = match ty.kind {
                     ty::Projection(data) => {
                         self.infcx.tcx.program_clauses_for(data.item_def_id)
                     }
diff --git a/src/librustc_traits/chalk_context/resolvent_ops.rs b/src/librustc_traits/chalk_context/resolvent_ops.rs
index c7aa6fe105e54..a871ad4b160e9 100644
--- a/src/librustc_traits/chalk_context/resolvent_ops.rs
+++ b/src/librustc_traits/chalk_context/resolvent_ops.rs
@@ -212,7 +212,7 @@ impl TypeRelation<'tcx> for AnswerSubstitutor<'cx, 'tcx> {
         let b = self.infcx.shallow_resolve(b);
         debug!("AnswerSubstitutor::tys(a = {:?}, b = {:?})", a, b);
 
-        if let &ty::Bound(debruijn, bound_ty) = &a.sty {
+        if let &ty::Bound(debruijn, bound_ty) = &a.kind {
             // Free bound var
             if debruijn == self.binder_index {
                 self.unify_free_answer_var(bound_ty.var, b.into())?;
@@ -220,7 +220,7 @@ impl TypeRelation<'tcx> for AnswerSubstitutor<'cx, 'tcx> {
             }
         }
 
-        match (&a.sty, &b.sty) {
+        match (&a.kind, &b.kind) {
             (&ty::Bound(a_debruijn, a_bound), &ty::Bound(b_debruijn, b_bound)) => {
                 assert_eq!(a_debruijn, b_debruijn);
                 assert_eq!(a_bound.var, b_bound.var);
diff --git a/src/librustc_traits/dropck_outlives.rs b/src/librustc_traits/dropck_outlives.rs
index ecd888b606981..a36b381bed343 100644
--- a/src/librustc_traits/dropck_outlives.rs
+++ b/src/librustc_traits/dropck_outlives.rs
@@ -105,7 +105,7 @@ fn dropck_outlives<'tcx>(
 
                             debug!("dropck_outlives: ty from dtorck_types = {:?}", ty);
 
-                            match ty.sty {
+                            match ty.kind {
                                 // All parameters live for the duration of the
                                 // function.
                                 ty::Param(..) => {}
@@ -166,7 +166,7 @@ fn dtorck_constraint_for_ty<'tcx>(
         });
     }
 
-    let result = match ty.sty {
+    let result = match ty.kind {
         ty::Bool
         | ty::Char
         | ty::Int(_)
diff --git a/src/librustc_traits/lowering/environment.rs b/src/librustc_traits/lowering/environment.rs
index 9ff685bb4ee8a..759eced131981 100644
--- a/src/librustc_traits/lowering/environment.rs
+++ b/src/librustc_traits/lowering/environment.rs
@@ -25,7 +25,7 @@ impl ClauseVisitor<'a, 'tcx> {
     }
 
     fn visit_ty(&mut self, ty: Ty<'tcx>) {
-        match ty.sty {
+        match ty.kind {
             ty::Projection(data) => {
                 self.round.extend(
                     self.tcx.program_clauses_for(data.item_def_id)
diff --git a/src/librustc_traits/lowering/mod.rs b/src/librustc_traits/lowering/mod.rs
index 1558ce1bced52..4c30227150fb1 100644
--- a/src/librustc_traits/lowering/mod.rs
+++ b/src/librustc_traits/lowering/mod.rs
@@ -4,7 +4,7 @@ use rustc::hir::def::DefKind;
 use rustc::hir::def_id::DefId;
 use rustc::hir::intravisit::{self, NestedVisitorMap, Visitor};
 use rustc::hir::map::definitions::DefPathData;
-use rustc::hir::{self, ImplPolarity};
+use rustc::hir;
 use rustc::traits::{
     Clause,
     Clauses,
@@ -295,7 +295,7 @@ fn program_clauses_for_trait(tcx: TyCtxt<'_>, def_id: DefId) -> Clauses<'_> {
 }
 
 fn program_clauses_for_impl(tcx: TyCtxt<'tcx>, def_id: DefId) -> Clauses<'tcx> {
-    if let ImplPolarity::Negative = tcx.impl_polarity(def_id) {
+    if let ty::ImplPolarity::Negative = tcx.impl_polarity(def_id) {
         return List::empty();
     }
 
diff --git a/src/librustc_typeck/astconv.rs b/src/librustc_typeck/astconv.rs
index 718d12484f741..2cd74281306f1 100644
--- a/src/librustc_typeck/astconv.rs
+++ b/src/librustc_typeck/astconv.rs
@@ -1608,7 +1608,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
 
         // Check if we have an enum variant.
         let mut variant_resolution = None;
-        if let ty::Adt(adt_def, _) = qself_ty.sty {
+        if let ty::Adt(adt_def, _) = qself_ty.kind {
             if adt_def.is_enum() {
                 let variant_def = adt_def.variants.iter().find(|vd| {
                     tcx.hygienic_eq(assoc_ident, vd.ident, adt_def.did)
@@ -1626,7 +1626,7 @@ impl<'o, 'tcx> dyn AstConv<'tcx> + 'o {
 
         // Find the type of the associated item, and the trait where the associated
         // item is declared.
-        let bound = match (&qself_ty.sty, qself_res) {
+        let bound = match (&qself_ty.kind, qself_res) {
             (_, Res::SelfTy(Some(_), Some(impl_def_id))) => {
                 // `Self` in an impl of a trait -- we have a concrete self type and a
                 // trait reference.
diff --git a/src/librustc_typeck/check/autoderef.rs b/src/librustc_typeck/check/autoderef.rs
index ecdf28e5d7f0b..ab5cabcaa4f7f 100644
--- a/src/librustc_typeck/check/autoderef.rs
+++ b/src/librustc_typeck/check/autoderef.rs
@@ -189,7 +189,7 @@ impl<'a, 'tcx> Autoderef<'a, 'tcx> {
                 fcx.try_overloaded_deref(self.span, source, needs)
                     .and_then(|InferOk { value: method, obligations: o }| {
                         obligations.extend(o);
-                        if let ty::Ref(region, _, mutbl) = method.sig.output().sty {
+                        if let ty::Ref(region, _, mutbl) = method.sig.output().kind {
                             Some(OverloadedDeref {
                                 region,
                                 mutbl,
diff --git a/src/librustc_typeck/check/callee.rs b/src/librustc_typeck/check/callee.rs
index 710d847384e6c..e1f239d3d08dd 100644
--- a/src/librustc_typeck/check/callee.rs
+++ b/src/librustc_typeck/check/callee.rs
@@ -90,7 +90,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         );
 
         // If the callee is a bare function or a closure, then we're all set.
-        match adjusted_ty.sty {
+        match adjusted_ty.kind {
             ty::FnDef(..) | ty::FnPtr(_) => {
                 let adjustments = autoderef.adjust_steps(self, Needs::None);
                 self.apply_adjustments(callee_expr, adjustments);
@@ -212,7 +212,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 let method = self.register_infer_ok_obligations(ok);
                 let mut autoref = None;
                 if borrow {
-                    if let ty::Ref(region, _, mutbl) = method.sig.inputs()[0].sty {
+                    if let ty::Ref(region, _, mutbl) = method.sig.inputs()[0].kind {
                         let mutbl = match mutbl {
                             hir::MutImmutable => AutoBorrowMutability::Immutable,
                             hir::MutMutable => AutoBorrowMutability::Mutable {
@@ -268,7 +268,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         arg_exprs: &'tcx [hir::Expr],
         expected: Expectation<'tcx>,
     ) -> Ty<'tcx> {
-        let (fn_sig, def_span) = match callee_ty.sty {
+        let (fn_sig, def_span) = match callee_ty.kind {
             ty::FnDef(def_id, _) => (
                 callee_ty.fn_sig(self.tcx),
                 self.tcx.hir().span_if_local(def_id),
diff --git a/src/librustc_typeck/check/cast.rs b/src/librustc_typeck/check/cast.rs
index c216cc92b1e58..dfeb5fb958cd8 100644
--- a/src/librustc_typeck/check/cast.rs
+++ b/src/librustc_typeck/check/cast.rs
@@ -93,7 +93,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             return Ok(Some(PointerKind::Thin));
         }
 
-        Ok(match t.sty {
+        Ok(match t.kind {
             ty::Slice(_) | ty::Str => Some(PointerKind::Length),
             ty::Dynamic(ref tty, ..) =>
                 Some(PointerKind::Vtable(tty.principal_def_id())),
@@ -192,7 +192,7 @@ impl<'a, 'tcx> CastCheck<'tcx> {
         // For better error messages, check for some obviously unsized
         // cases now. We do a more thorough check at the end, once
         // inference is more completely known.
-        match cast_ty.sty {
+        match cast_ty.kind {
             ty::Dynamic(..) | ty::Slice(..) => {
                 check.report_cast_to_unsized_type(fcx);
                 Err(ErrorReported)
@@ -339,7 +339,7 @@ impl<'a, 'tcx> CastCheck<'tcx> {
                                          "cast to unsized type: `{}` as `{}`",
                                          fcx.resolve_vars_if_possible(&self.expr_ty),
                                          tstr);
-        match self.expr_ty.sty {
+        match self.expr_ty.kind {
             ty::Ref(_, _, mt) => {
                 let mtstr = match mt {
                     hir::MutMutable => "mut ",
@@ -455,7 +455,7 @@ impl<'a, 'tcx> CastCheck<'tcx> {
             (Some(t_from), Some(t_cast)) => (t_from, t_cast),
             // Function item types may need to be reified before casts.
             (None, Some(t_cast)) => {
-                if let ty::FnDef(..) = self.expr_ty.sty {
+                if let ty::FnDef(..) = self.expr_ty.kind {
                     // Attempt a coercion to a fn pointer type.
                     let f = self.expr_ty.fn_sig(fcx.tcx);
                     let res = fcx.try_coerce(self.expr,
@@ -505,7 +505,7 @@ impl<'a, 'tcx> CastCheck<'tcx> {
             (FnPtr, Int(_)) => Ok(CastKind::FnPtrAddrCast),
             (RPtr(p), Int(_)) |
             (RPtr(p), Float) => {
-                match p.ty.sty {
+                match p.ty.kind {
                     ty::Int(_) |
                     ty::Uint(_) |
                     ty::Float(_) => {
@@ -616,7 +616,7 @@ impl<'a, 'tcx> CastCheck<'tcx> {
         // array-ptr-cast.
 
         if m_expr.mutbl == hir::MutImmutable && m_cast.mutbl == hir::MutImmutable {
-            if let ty::Array(ety, _) = m_expr.ty.sty {
+            if let ty::Array(ety, _) = m_expr.ty.kind {
                 // Due to the limitations of LLVM global constants,
                 // region pointers end up pointing at copies of
                 // vector elements instead of the original values.
diff --git a/src/librustc_typeck/check/closure.rs b/src/librustc_typeck/check/closure.rs
index d626bff150020..bdf8f3b1d4ae6 100644
--- a/src/librustc_typeck/check/closure.rs
+++ b/src/librustc_typeck/check/closure.rs
@@ -186,7 +186,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             expected_ty
         );
 
-        match expected_ty.sty {
+        match expected_ty.kind {
             ty::Dynamic(ref object_type, ..) => {
                 let sig = object_type
                     .projection_bounds()
@@ -288,7 +288,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             let arg_param_ty = self.resolve_vars_if_possible(&arg_param_ty);
             debug!("deduce_sig_from_projection: arg_param_ty={:?}", arg_param_ty);
 
-            match arg_param_ty.sty {
+            match arg_param_ty.kind {
                 ty::Tuple(tys) => tys.into_iter().map(|k| k.expect_ty()).collect::<Vec<_>>(),
                 _ => return None,
             }
diff --git a/src/librustc_typeck/check/coercion.rs b/src/librustc_typeck/check/coercion.rs
index dc536329251ca..564a0eac75539 100644
--- a/src/librustc_typeck/check/coercion.rs
+++ b/src/librustc_typeck/check/coercion.rs
@@ -206,7 +206,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
         //
         // Note: does not attempt to resolve type variables we encounter.
         // See above for details.
-        match b.sty {
+        match b.kind {
             ty::RawPtr(mt_b) => {
                 return self.coerce_unsafe_ptr(a, b, mt_b.mutbl);
             }
@@ -219,7 +219,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
             _ => {}
         }
 
-        match a.sty {
+        match a.kind {
             ty::FnDef(..) => {
                 // Function items are coercible to any closure
                 // type; function pointers are not (that would
@@ -264,7 +264,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
         // to type check, we will construct the type that `&M*expr` would
         // yield.
 
-        let (r_a, mt_a) = match a.sty {
+        let (r_a, mt_a) = match a.kind {
             ty::Ref(r_a, ty, mutbl) => {
                 let mt_a = ty::TypeAndMut { ty, mutbl };
                 coerce_mutbls(mt_a.mutbl, mt_b.mutbl)?;
@@ -426,7 +426,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
 
         // Now apply the autoref. We have to extract the region out of
         // the final ref type we got.
-        let r_borrow = match ty.sty {
+        let r_borrow = match ty.kind {
             ty::Ref(r_borrow, _, _) => r_borrow,
             _ => span_bug!(span, "expected a ref type, got {:?}", ty),
         };
@@ -470,7 +470,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
         // that, at which point we will need extra checks on the target here.
 
         // Handle reborrows before selecting `Source: CoerceUnsized<Target>`.
-        let reborrow = match (&source.sty, &target.sty) {
+        let reborrow = match (&source.kind, &target.kind) {
             (&ty::Ref(_, ty_a, mutbl_a), &ty::Ref(_, _, mutbl_b)) => {
                 coerce_mutbls(mutbl_a, mutbl_b)?;
 
@@ -566,15 +566,14 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
             let obligation = queue.remove(0);
             debug!("coerce_unsized resolve step: {:?}", obligation);
             let trait_ref = match obligation.predicate {
-                ty::Predicate::Trait(ref tr) if traits.contains(&tr.def_id()) => {
-                    if unsize_did == tr.def_id() {
-                        let sty = &tr.skip_binder().input_types().nth(1).unwrap().sty;
-                        if let ty::Tuple(..) = sty {
+                ty::Predicate::Trait(ref t) if traits.contains(&t.def_id()) => {
+                    if unsize_did == t.def_id() {
+                        if let ty::Tuple(..) = &t.skip_binder().input_types().nth(1).unwrap().kind {
                             debug!("coerce_unsized: found unsized tuple coercion");
                             has_unsized_tuple_coercion = true;
                         }
                     }
-                    tr.clone()
+                    t.clone()
                 }
                 _ => {
                     coercion.obligations.push(obligation);
@@ -589,7 +588,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
                         let self_ty = trait_ref.skip_binder().self_ty();
                         let unsize_ty = trait_ref.skip_binder().input_types().nth(1).unwrap();
                         debug!("coerce_unsized: ambiguous unsize case for {:?}", trait_ref);
-                        match (&self_ty.sty, &unsize_ty.sty) {
+                        match (&self_ty.kind, &unsize_ty.kind) {
                             (ty::Infer(ty::TyVar(v)),
                              ty::Dynamic(..)) if self.type_var_is_sized(*v) => {
                                 debug!("coerce_unsized: have sized infer {:?}", v);
@@ -650,7 +649,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
         where F: FnOnce(Ty<'tcx>) -> Vec<Adjustment<'tcx>>,
               G: FnOnce(Ty<'tcx>) -> Vec<Adjustment<'tcx>>
     {
-        if let ty::FnPtr(fn_ty_b) = b.sty {
+        if let ty::FnPtr(fn_ty_b) = b.kind {
             if let (hir::Unsafety::Normal, hir::Unsafety::Unsafe)
                 = (fn_ty_a.unsafety(), fn_ty_b.unsafety())
             {
@@ -687,7 +686,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
         let b = self.shallow_resolve(b);
         debug!("coerce_from_fn_item(a={:?}, b={:?})", a, b);
 
-        match b.sty {
+        match b.kind {
             ty::FnPtr(_) => {
                 let a_sig = a.fn_sig(self.tcx);
                 // Intrinsics are not coercible to function pointers
@@ -737,7 +736,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
 
         let b = self.shallow_resolve(b);
 
-        match b.sty {
+        match b.kind {
             ty::FnPtr(fn_ty) if self.tcx.upvars(def_id_a).map_or(true, |v| v.is_empty()) => {
                 // We coerce the closure, which has fn type
                 //     `extern "rust-call" fn((arg0,arg1,...)) -> _`
@@ -765,7 +764,7 @@ impl<'f, 'tcx> Coerce<'f, 'tcx> {
                          -> CoerceResult<'tcx> {
         debug!("coerce_unsafe_ptr(a={:?}, b={:?})", a, b);
 
-        let (is_ref, mt_a) = match a.sty {
+        let (is_ref, mt_a) = match a.kind {
             ty::Ref(_, ty, mutbl) => (true, ty::TypeAndMut { ty, mutbl }),
             ty::RawPtr(mt) => (false, mt),
             _ => return self.unify_and(a, b, identity)
@@ -860,7 +859,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         // Special-case that coercion alone cannot handle:
         // Two function item types of differing IDs or InternalSubsts.
-        if let (&ty::FnDef(..), &ty::FnDef(..)) = (&prev_ty.sty, &new_ty.sty) {
+        if let (&ty::FnDef(..), &ty::FnDef(..)) = (&prev_ty.kind, &new_ty.kind) {
             // Don't reify if the function types have a LUB, i.e., they
             // are the same function and their parameters have a LUB.
             let lub_ty = self.commit_if_ok(|_| {
@@ -929,7 +928,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     Adjustment { kind: Adjust::Deref(_), .. },
                     Adjustment { kind: Adjust::Borrow(AutoBorrow::Ref(_, mutbl_adj)), .. }
                 ] => {
-                    match self.node_ty(expr.hir_id).sty {
+                    match self.node_ty(expr.hir_id).kind {
                         ty::Ref(_, _, mt_orig) => {
                             let mutbl_adj: hir::Mutability = mutbl_adj.into();
                             // Reborrow that we can safely ignore, because
diff --git a/src/librustc_typeck/check/demand.rs b/src/librustc_typeck/check/demand.rs
index 63137bad52ff8..6c94f833196fb 100644
--- a/src/librustc_typeck/check/demand.rs
+++ b/src/librustc_typeck/check/demand.rs
@@ -150,7 +150,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expected: Ty<'tcx>,
         expr_ty: Ty<'tcx>,
     ) {
-        if let ty::Adt(expected_adt, substs) = expected.sty {
+        if let ty::Adt(expected_adt, substs) = expected.kind {
             if !expected_adt.is_enum() {
                 return;
             }
@@ -351,8 +351,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         // and make a good suggestion, so don't bother.
         let is_macro = sp.from_expansion();
 
-        match (&expr.node, &expected.sty, &checked_ty.sty) {
-            (_, &ty::Ref(_, exp, _), &ty::Ref(_, check, _)) => match (&exp.sty, &check.sty) {
+        match (&expr.node, &expected.kind, &checked_ty.kind) {
+            (_, &ty::Ref(_, exp, _), &ty::Ref(_, check, _)) => match (&exp.kind, &check.kind) {
                 (&ty::Str, &ty::Array(arr, _)) |
                 (&ty::Str, &ty::Slice(arr)) if arr == self.tcx.types.u8 => {
                     if let hir::ExprKind::Lit(_) = expr.node {
@@ -650,8 +650,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 "{}{}{}{}",
                 if needs_paren { "(" } else { "" },
                 if let (ty::Int(_), ty::Float(_)) | (ty::Uint(_), ty::Float(_)) = (
-                    &expected_ty.sty,
-                    &checked_ty.sty,
+                    &expected_ty.kind,
+                    &checked_ty.kind,
                 ) {
                     // Remove fractional part from literal, for example `42.0f32` into `42`
                     let src = src.trim_end_matches(&checked_ty.to_string());
@@ -695,7 +695,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 );
             };
 
-            match (&expected_ty.sty, &checked_ty.sty) {
+            match (&expected_ty.kind, &checked_ty.kind) {
                 (&ty::Int(ref exp), &ty::Int(ref found)) => {
                     let is_fallible = match (found.bit_width(), exp.bit_width()) {
                         (Some(found), Some(exp)) if found > exp => true,
diff --git a/src/librustc_typeck/check/dropck.rs b/src/librustc_typeck/check/dropck.rs
index babffe479bc2e..a144e5938c3a8 100644
--- a/src/librustc_typeck/check/dropck.rs
+++ b/src/librustc_typeck/check/dropck.rs
@@ -32,7 +32,7 @@ use syntax_pos::Span;
 pub fn check_drop_impl(tcx: TyCtxt<'_>, drop_impl_did: DefId) -> Result<(), ErrorReported> {
     let dtor_self_type = tcx.type_of(drop_impl_did);
     let dtor_predicates = tcx.predicates_of(drop_impl_did);
-    match dtor_self_type.sty {
+    match dtor_self_type.kind {
         ty::Adt(adt_def, self_to_impl_substs) => {
             ensure_drop_params_and_item_params_correspond(
                 tcx,
diff --git a/src/librustc_typeck/check/expr.rs b/src/librustc_typeck/check/expr.rs
index 6b694bfc8da25..97fcfd7151a1c 100644
--- a/src/librustc_typeck/check/expr.rs
+++ b/src/librustc_typeck/check/expr.rs
@@ -305,7 +305,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
     fn check_expr_box(&self, expr: &'tcx hir::Expr, expected: Expectation<'tcx>) -> Ty<'tcx> {
         let expected_inner = expected.to_option(self).map_or(NoExpectation, |ty| {
-            match ty.sty {
+            match ty.kind {
                 ty::Adt(def, _) if def.is_box()
                     => Expectation::rvalue_hint(self, ty.boxed_ty()),
                 _ => NoExpectation
@@ -343,7 +343,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     } else if let Some(ok) = self.try_overloaded_deref(
                             expr.span, oprnd_t, needs) {
                         let method = self.register_infer_ok_obligations(ok);
-                        if let ty::Ref(region, _, mutbl) = method.sig.inputs()[0].sty {
+                        if let ty::Ref(region, _, mutbl) = method.sig.inputs()[0].kind {
                             let mutbl = match mutbl {
                                 hir::MutImmutable => AutoBorrowMutability::Immutable,
                                 hir::MutMutable => AutoBorrowMutability::Mutable {
@@ -386,7 +386,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 hir::UnNot => {
                     let result = self.check_user_unop(expr, oprnd_t, unop);
                     // If it's builtin, we can reuse the type, this helps inference.
-                    if !(oprnd_t.is_integral() || oprnd_t.sty == ty::Bool) {
+                    if !(oprnd_t.is_integral() || oprnd_t.kind == ty::Bool) {
                         oprnd_t = result;
                     }
                 }
@@ -410,7 +410,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expr: &'tcx hir::Expr,
     ) -> Ty<'tcx> {
         let hint = expected.only_has_type(self).map_or(NoExpectation, |ty| {
-            match ty.sty {
+            match ty.kind {
                 ty::Ref(_, ty, _) | ty::RawPtr(ty::TypeAndMut { ty, .. }) => {
                     if oprnd.is_place_expr() {
                         // Places may legitimately have unsized types.
@@ -464,7 +464,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             _ => self.instantiate_value_path(segs, opt_ty, res, expr.span, expr.hir_id).0,
         };
 
-        if let ty::FnDef(..) = ty.sty {
+        if let ty::FnDef(..) = ty.kind {
             let fn_sig = ty.fn_sig(tcx);
             if !tcx.features().unsized_locals {
                 // We want to remove some Sized bounds from std functions,
@@ -556,7 +556,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     assert!(e_ty.is_unit());
                     let ty = coerce.expected_ty();
                     coerce.coerce_forced_unit(self, &cause, &mut |err| {
-                        let val = match ty.sty {
+                        let val = match ty.kind {
                             ty::Bool => "true",
                             ty::Char => "'a'",
                             ty::Int(_) | ty::Uint(_) => "42",
@@ -838,7 +838,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             error,
             Some(args),
         ) {
-            if let ty::Adt(..) = rcvr_t.sty {
+            if let ty::Adt(..) = rcvr_t.kind {
                 // Try alternative arbitrary self types that could fulfill this call.
                 // FIXME: probe for all types that *could* be arbitrary self-types, not
                 // just this whitelist.
@@ -889,7 +889,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         expr: &'tcx hir::Expr
     ) -> Ty<'tcx> {
         let uty = expected.to_option(self).and_then(|uty| {
-            match uty.sty {
+            match uty.kind {
                 ty::Array(ty, _) | ty::Slice(ty) => Some(ty),
                 _ => None
             }
@@ -949,7 +949,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         let uty = match expected {
             ExpectHasType(uty) => {
-                match uty.sty {
+                match uty.kind {
                     ty::Array(ty, _) | ty::Slice(ty) => Some(ty),
                     _ => None
                 }
@@ -989,7 +989,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     ) -> Ty<'tcx> {
         let flds = expected.only_has_type(self).and_then(|ty| {
             let ty = self.resolve_type_vars_with_obligations(ty);
-            match ty.sty {
+            match ty.kind {
                 ty::Tuple(ref flds) => Some(&flds[..]),
                 _ => None
             }
@@ -1055,7 +1055,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             // when certain fields are assumed to exist that in fact do not.
             if !error_happened {
                 self.check_expr_has_type_or_error(base_expr, adt_ty);
-                match adt_ty.sty {
+                match adt_ty.kind {
                     ty::Adt(adt, substs) if adt.is_struct() => {
                         let fru_field_types = adt.non_enum_variant().fields.iter().map(|f| {
                             self.normalize_associated_types_in(expr.span, &f.ty(self.tcx, substs))
@@ -1095,7 +1095,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         // re-link the regions that EIfEO can erase.
         self.demand_eqtype(span, adt_ty_hint, adt_ty);
 
-        let (substs, adt_kind, kind_name) = match &adt_ty.sty {
+        let (substs, adt_kind, kind_name) = match &adt_ty.kind {
             &ty::Adt(adt, substs) => {
                 (substs, adt.adt_kind(), adt.variant_descr())
             }
@@ -1217,7 +1217,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         }
         let mut err = self.type_error_struct_with_diag(
             field.ident.span,
-            |actual| match ty.sty {
+            |actual| match ty.kind {
                 ty::Adt(adt, ..) if adt.is_enum() => {
                     struct_span_err!(self.tcx.sess, field.ident.span, E0559,
                                      "{} `{}::{}` has no field named `{}`",
@@ -1256,7 +1256,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                         Applicability::MaybeIncorrect,
                     );
                 } else {
-                    match ty.sty {
+                    match ty.kind {
                         ty::Adt(adt, ..) => {
                             if adt.is_enum() {
                                 err.span_label(field.ident.span, format!(
@@ -1338,7 +1338,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let mut private_candidate = None;
         let mut autoderef = self.autoderef(expr.span, expr_t);
         while let Some((base_t, _)) = autoderef.next() {
-            match base_t.sty {
+            match base_t.kind {
                 ty::Adt(base_def, substs) if !base_def.is_enum() => {
                     debug!("struct named {:?}",  base_t);
                     let (ident, def_scope) =
@@ -1392,7 +1392,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         } else if !expr_t.is_primitive_ty() {
             let mut err = self.no_such_field_err(field.span, field, expr_t);
 
-            match expr_t.sty {
+            match expr_t.kind {
                 ty::Adt(def, _) if !def.is_enum() => {
                     self.suggest_fields_on_recordish(&mut err, def, field);
                 }
@@ -1600,7 +1600,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                             "cannot index into a value of type `{}`",
                                             base_t);
                     // Try to give some advice about indexing tuples.
-                    if let ty::Tuple(..) = base_t.sty {
+                    if let ty::Tuple(..) = base_t.kind {
                         let mut needs_note = true;
                         // If the index is an integer, we can show the actual
                         // fixed expression:
diff --git a/src/librustc_typeck/check/method/confirm.rs b/src/librustc_typeck/check/method/confirm.rs
index 5df0010b63eb2..5d4893ae75483 100644
--- a/src/librustc_typeck/check/method/confirm.rs
+++ b/src/librustc_typeck/check/method/confirm.rs
@@ -277,7 +277,7 @@ impl<'a, 'tcx> ConfirmContext<'a, 'tcx> {
             .autoderef(self.span, self_ty)
             .include_raw_pointers()
             .filter_map(|(ty, _)|
-                match ty.sty {
+                match ty.kind {
                     ty::Dynamic(ref data, ..) => {
                         Some(closure(self, ty, data.principal().unwrap_or_else(|| {
                             span_bug!(self.span, "calling trait method on empty object?")
@@ -467,7 +467,7 @@ impl<'a, 'tcx> ConfirmContext<'a, 'tcx> {
                     if let Adjust::Deref(Some(ref mut deref)) = adjustment.kind {
                         if let Some(ok) = self.try_overloaded_deref(expr.span, source, needs) {
                             let method = self.register_infer_ok_obligations(ok);
-                            if let ty::Ref(region, _, mutbl) = method.sig.output().sty {
+                            if let ty::Ref(region, _, mutbl) = method.sig.output().kind {
                                 *deref = OverloadedDeref {
                                     region,
                                     mutbl,
@@ -526,7 +526,7 @@ impl<'a, 'tcx> ConfirmContext<'a, 'tcx> {
         debug!("convert_place_op_to_mutable: method={:?}", method);
         self.write_method_call(expr.hir_id, method);
 
-        let (region, mutbl) = if let ty::Ref(r, _, mutbl) = method.sig.inputs()[0].sty {
+        let (region, mutbl) = if let ty::Ref(r, _, mutbl) = method.sig.inputs()[0].kind {
             (r, mutbl)
         } else {
             span_bug!(expr.span, "input to place op is not a ref?");
@@ -592,7 +592,7 @@ impl<'a, 'tcx> ConfirmContext<'a, 'tcx> {
                 }
             })
             .any(|trait_pred| {
-                match trait_pred.skip_binder().self_ty().sty {
+                match trait_pred.skip_binder().self_ty().kind {
                     ty::Dynamic(..) => true,
                     _ => false,
                 }
diff --git a/src/librustc_typeck/check/method/mod.rs b/src/librustc_typeck/check/method/mod.rs
index 1509c0f8a2196..2be311127214d 100644
--- a/src/librustc_typeck/check/method/mod.rs
+++ b/src/librustc_typeck/check/method/mod.rs
@@ -410,7 +410,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let tcx = self.tcx;
 
         // Check if we have an enum variant.
-        if let ty::Adt(adt_def, _) = self_ty.sty {
+        if let ty::Adt(adt_def, _) = self_ty.kind {
             if adt_def.is_enum() {
                 let variant_def = adt_def.variants.iter().find(|vd| {
                     tcx.hygienic_eq(method_name, vd.ident, adt_def.did)
diff --git a/src/librustc_typeck/check/method/probe.rs b/src/librustc_typeck/check/method/probe.rs
index c8838311e8dbf..593cf77a4a6c7 100644
--- a/src/librustc_typeck/check/method/probe.rs
+++ b/src/librustc_typeck/check/method/probe.rs
@@ -419,7 +419,7 @@ fn method_autoderef_steps<'tcx>(
                     from_unsafe_deref: reached_raw_pointer,
                     unsize: false,
                 };
-                if let ty::RawPtr(_) = ty.sty {
+                if let ty::RawPtr(_) = ty.kind {
                     // all the subsequent steps will be from_unsafe_deref
                     reached_raw_pointer = true;
                 }
@@ -428,7 +428,7 @@ fn method_autoderef_steps<'tcx>(
             .collect();
 
         let final_ty = autoderef.maybe_ambiguous_final_ty();
-        let opt_bad_ty = match final_ty.sty {
+        let opt_bad_ty = match final_ty.kind {
             ty::Infer(ty::TyVar(_)) |
             ty::Error => {
                 Some(MethodAutoderefBadTy {
@@ -541,7 +541,7 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
         debug!("assemble_probe: self_ty={:?}", self_ty);
         let lang_items = self.tcx.lang_items();
 
-        match self_ty.value.value.sty {
+        match self_ty.value.value.kind {
             ty::Dynamic(ref data, ..) => {
                 if let Some(p) = data.principal() {
                     // Subtle: we can't use `instantiate_query_response` here: using it will
@@ -735,7 +735,7 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
         debug!("assemble_inherent_candidates_from_object(self_ty={:?})",
                self_ty);
 
-        let principal = match self_ty.sty {
+        let principal = match self_ty.kind {
             ty::Dynamic(ref data, ..) => Some(data),
             _ => None
         }.and_then(|data| data.principal()).unwrap_or_else(|| {
@@ -773,7 +773,7 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
             .filter_map(|predicate| {
                 match *predicate {
                     ty::Predicate::Trait(ref trait_predicate) => {
-                        match trait_predicate.skip_binder().trait_ref.self_ty().sty {
+                        match trait_predicate.skip_binder().trait_ref.self_ty().kind {
                             ty::Param(ref p) if *p == param_ty => {
                                 Some(trait_predicate.to_poly_trait_ref())
                             }
@@ -1073,7 +1073,7 @@ impl<'a, 'tcx> ProbeContext<'a, 'tcx> {
                 pick.autoderefs = step.autoderefs;
 
                 // Insert a `&*` or `&mut *` if this is a reference type:
-                if let ty::Ref(_, _, mutbl) = step.self_ty.value.value.sty {
+                if let ty::Ref(_, _, mutbl) = step.self_ty.value.value.kind {
                     pick.autoderefs += 1;
                     pick.autoref = Some(mutbl);
                 }
diff --git a/src/librustc_typeck/check/method/suggest.rs b/src/librustc_typeck/check/method/suggest.rs
index 4c681544978e5..408532d1d1ee8 100644
--- a/src/librustc_typeck/check/method/suggest.rs
+++ b/src/librustc_typeck/check/method/suggest.rs
@@ -26,7 +26,7 @@ use super::probe::Mode;
 impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     fn is_fn_ty(&self, ty: Ty<'tcx>, span: Span) -> bool {
         let tcx = self.tcx;
-        match ty.sty {
+        match ty.kind {
             // Not all of these (e.g., unsafe fns) implement `FnOnce`,
             // so we look for these beforehand.
             ty::Closure(..) |
@@ -339,7 +339,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 );
                             }
                         }
-                        if let ty::RawPtr(_) = &actual.sty {
+                        if let ty::RawPtr(_) = &actual.kind {
                             err.note("try using `<*const T>::as_ref()` to get a reference to the \
                                       type behind the pointer: https://doc.rust-lang.org/std/\
                                       primitive.pointer.html#method.as_ref");
@@ -372,7 +372,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 if let SelfSource::MethodCall(expr) = source {
                     let field_receiver = self
                         .autoderef(span, rcvr_ty)
-                        .find_map(|(ty, _)| match ty.sty {
+                        .find_map(|(ty, _)| match ty.kind {
                             ty::Adt(def, substs) if !def.is_enum() => {
                                 let variant = &def.non_enum_variant();
                                 self.tcx.find_field_index(item_name, variant).map(|index| {
@@ -701,9 +701,9 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             candidates.sort_by(|a, b| a.cmp(b).reverse());
             candidates.dedup();
 
-            let param_type = match rcvr_ty.sty {
+            let param_type = match rcvr_ty.kind {
                 ty::Param(param) => Some(param),
-                ty::Ref(_, ty, _) => match ty.sty {
+                ty::Ref(_, ty, _) => match ty.kind {
                     ty::Param(param) => Some(param),
                     _ => None,
                 }
@@ -815,7 +815,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             rcvr_ty: Ty<'tcx>,
                             source: SelfSource<'_>) -> bool {
         fn is_local(ty: Ty<'_>) -> bool {
-            match ty.sty {
+            match ty.kind {
                 ty::Adt(def, _) => def.did.is_local(),
                 ty::Foreign(did) => did.is_local(),
 
diff --git a/src/librustc_typeck/check/mod.rs b/src/librustc_typeck/check/mod.rs
index 02f4f2a3744c6..1d572c141211b 100644
--- a/src/librustc_typeck/check/mod.rs
+++ b/src/librustc_typeck/check/mod.rs
@@ -316,7 +316,7 @@ impl<'a, 'tcx> Expectation<'tcx> {
     /// See the test case `test/ui/coerce-expect-unsized.rs` and #20169
     /// for examples of where this comes up,.
     fn rvalue_hint(fcx: &FnCtxt<'a, 'tcx>, ty: Ty<'tcx>) -> Expectation<'tcx> {
-        match fcx.tcx.struct_tail_without_normalization(ty).sty {
+        match fcx.tcx.struct_tail_without_normalization(ty).kind {
             ty::Slice(_) | ty::Str | ty::Dynamic(..) => {
                 ExpectRvalueLikeUnsized(ty)
             }
@@ -1230,7 +1230,7 @@ fn check_fn<'a, 'tcx>(
                 // only happens if compilation succeeded
                 fcx.tcx.sess.has_panic_handler.try_set_same(true);
 
-                if declared_ret_ty.sty != ty::Never {
+                if declared_ret_ty.kind != ty::Never {
                     fcx.tcx.sess.span_err(
                         decl.output.span(),
                         "return type should be `!`",
@@ -1240,8 +1240,8 @@ fn check_fn<'a, 'tcx>(
                 let inputs = fn_sig.inputs();
                 let span = fcx.tcx.hir().span(fn_id);
                 if inputs.len() == 1 {
-                    let arg_is_panic_info = match inputs[0].sty {
-                        ty::Ref(region, ty, mutbl) => match ty.sty {
+                    let arg_is_panic_info = match inputs[0].kind {
+                        ty::Ref(region, ty, mutbl) => match ty.kind {
                             ty::Adt(ref adt, _) => {
                                 adt.did == panic_info_did &&
                                     mutbl == hir::Mutability::MutImmutable &&
@@ -1283,7 +1283,7 @@ fn check_fn<'a, 'tcx>(
     if let Some(alloc_error_handler_did) = fcx.tcx.lang_items().oom() {
         if alloc_error_handler_did == fcx.tcx.hir().local_def_id(fn_id) {
             if let Some(alloc_layout_did) = fcx.tcx.lang_items().alloc_layout() {
-                if declared_ret_ty.sty != ty::Never {
+                if declared_ret_ty.kind != ty::Never {
                     fcx.tcx.sess.span_err(
                         decl.output.span(),
                         "return type should be `!`",
@@ -1293,7 +1293,7 @@ fn check_fn<'a, 'tcx>(
                 let inputs = fn_sig.inputs();
                 let span = fcx.tcx.hir().span(fn_id);
                 if inputs.len() == 1 {
-                    let arg_is_alloc_layout = match inputs[0].sty {
+                    let arg_is_alloc_layout = match inputs[0].kind {
                         ty::Adt(ref adt, _) => {
                             adt.did == alloc_layout_did
                         },
@@ -1458,7 +1458,7 @@ fn check_opaque_for_cycles<'tcx>(
                 "opaque type expands to a recursive type",
             );
             err.span_label(span, "expands to a recursive type");
-            if let ty::Opaque(..) = partially_expanded_type.sty {
+            if let ty::Opaque(..) = partially_expanded_type.kind {
                 err.note("type resolves to itself");
             } else {
                 err.note(&format!("expanded type is `{}`", partially_expanded_type));
@@ -1884,7 +1884,7 @@ fn check_representable(tcx: TyCtxt<'_>, sp: Span, item_def_id: DefId) -> bool {
 
 pub fn check_simd(tcx: TyCtxt<'_>, sp: Span, def_id: DefId) {
     let t = tcx.type_of(def_id);
-    if let ty::Adt(def, substs) = t.sty {
+    if let ty::Adt(def, substs) = t.kind {
         if def.is_struct() {
             let fields = &def.non_enum_variant().fields;
             if fields.is_empty() {
@@ -1898,7 +1898,7 @@ pub fn check_simd(tcx: TyCtxt<'_>, sp: Span, def_id: DefId) {
                                 .emit();
                 return;
             }
-            match e.sty {
+            match e.kind {
                 ty::Param(_) => { /* struct<T>(T, T, T, T) is ok */ }
                 _ if e.is_machine() => { /* struct(u8, u8, u8, u8) is ok */ }
                 _ => {
@@ -1945,7 +1945,7 @@ fn check_packed_inner(tcx: TyCtxt<'_>, def_id: DefId, stack: &mut Vec<DefId>) ->
         debug!("check_packed_inner: {:?} is recursive", t);
         return false;
     }
-    if let ty::Adt(def, substs) = t.sty {
+    if let ty::Adt(def, substs) = t.kind {
         if def.is_struct() || def.is_union() {
             if tcx.adt_def(def.did).repr.align.is_some() {
                 return true;
@@ -1954,7 +1954,7 @@ fn check_packed_inner(tcx: TyCtxt<'_>, def_id: DefId, stack: &mut Vec<DefId>) ->
             stack.push(def_id);
             for field in &def.non_enum_variant().fields {
                 let f = field.ty(tcx, substs);
-                if let ty::Adt(def, _) = f.sty {
+                if let ty::Adt(def, _) = f.kind {
                     if check_packed_inner(tcx, def.did, stack) {
                         return true;
                     }
@@ -2974,7 +2974,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             let mut self_ty = adjusted_ty;
             if unsize {
                 // We only unsize arrays here.
-                if let ty::Array(element_ty, _) = adjusted_ty.sty {
+                if let ty::Array(element_ty, _) = adjusted_ty.kind {
                     self_ty = self.tcx.mk_slice(element_ty);
                 } else {
                     continue;
@@ -2996,7 +2996,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 let method = self.register_infer_ok_obligations(ok);
 
                 let mut adjustments = autoderef.adjust_steps(self, needs);
-                if let ty::Ref(region, _, r_mutbl) = method.sig.inputs()[0].sty {
+                if let ty::Ref(region, _, r_mutbl) = method.sig.inputs()[0].kind {
                     let mutbl = match r_mutbl {
                         hir::MutImmutable => AutoBorrowMutability::Immutable,
                         hir::MutMutable => AutoBorrowMutability::Mutable {
@@ -3147,7 +3147,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             "self_type_matches_expected_vid(trait_ref={:?}, self_ty={:?}, expected_vid={:?})",
             trait_ref, self_ty, expected_vid
         );
-        match self_ty.sty {
+        match self_ty.kind {
             ty::Infer(ty::TyVar(found_vid)) => {
                 // FIXME: consider using `sub_root_var` here so we
                 // can see through subtyping.
@@ -3272,7 +3272,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         let formal_tys = if tuple_arguments == TupleArguments {
             let tuple_type = self.structurally_resolved_type(sp, fn_inputs[0]);
-            match tuple_type.sty {
+            match tuple_type.kind {
                 ty::Tuple(arg_types) if arg_types.len() != args.len() => {
                     param_count_error(arg_types.len(), args.len(), "E0057", false, false);
                     expected_arg_tys = vec![];
@@ -3280,7 +3280,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 }
                 ty::Tuple(arg_types) => {
                     expected_arg_tys = match expected_arg_tys.get(0) {
-                        Some(&ty) => match ty.sty {
+                        Some(&ty) => match ty.kind {
                             ty::Tuple(ref tys) => tys.iter().map(|k| k.expect_ty()).collect(),
                             _ => vec![],
                         },
@@ -3421,7 +3421,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 // There are a few types which get autopromoted when passed via varargs
                 // in C but we just error out instead and require explicit casts.
                 let arg_ty = self.structurally_resolved_type(arg.span, arg_ty);
-                match arg_ty.sty {
+                match arg_ty.kind {
                     ty::Float(ast::FloatTy::F32) => {
                         variadic_error(tcx.sess, arg.span, arg_ty, "c_double");
                     }
@@ -3548,7 +3548,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             ast::LitKind::Int(_, ast::LitIntType::Unsigned(t)) => tcx.mk_mach_uint(t),
             ast::LitKind::Int(_, ast::LitIntType::Unsuffixed) => {
                 let opt_ty = expected.to_option(self).and_then(|ty| {
-                    match ty.sty {
+                    match ty.kind {
                         ty::Int(_) | ty::Uint(_) => Some(ty),
                         ty::Char => Some(tcx.types.u8),
                         ty::RawPtr(..) => Some(tcx.types.usize),
@@ -3561,7 +3561,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             ast::LitKind::Float(_, t) => tcx.mk_mach_float(t),
             ast::LitKind::FloatUnsuffixed(_) => {
                 let opt_ty = expected.to_option(self).and_then(|ty| {
-                    match ty.sty {
+                    match ty.kind {
                         ty::Float(_) => Some(ty),
                         _ => None
                     }
@@ -3657,7 +3657,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 return None;
             }
             Res::Def(DefKind::Variant, _) => {
-                match ty.sty {
+                match ty.kind {
                     ty::Adt(adt, substs) => {
                         Some((adt.variant_of_res(def), adt.did, substs))
                     }
@@ -3669,7 +3669,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             | Res::Def(DefKind::TyAlias, _)
             | Res::Def(DefKind::AssocTy, _)
             | Res::SelfTy(..) => {
-                match ty.sty {
+                match ty.kind {
                     ty::Adt(adt, substs) if !adt.is_enum() => {
                         Some((adt.non_enum_variant(), adt.did, substs))
                     }
@@ -4163,13 +4163,13 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         found: Ty<'tcx>,
     ) -> bool {
         let hir = self.tcx.hir();
-        let (def_id, sig) = match found.sty {
+        let (def_id, sig) = match found.kind {
             ty::FnDef(def_id, _) => (def_id, found.fn_sig(self.tcx)),
             ty::Closure(def_id, substs) => {
                 // We don't use `closure_sig` to account for malformed closures like
                 // `|_: [_; continue]| {}` and instead we don't suggest anything.
                 let closure_sig_ty = substs.closure_sig_ty(def_id, self.tcx);
-                (def_id, match closure_sig_ty.sty {
+                (def_id, match closure_sig_ty.kind {
                     ty::FnPtr(sig) => sig,
                     _ => return false,
                 })
@@ -4283,7 +4283,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 Applicability::MachineApplicable,
             );
         } else if let (ty::FnDef(def_id, ..), true) = (
-            &found.sty,
+            &found.kind,
             self.suggest_fn_call(err, expr, expected, found),
         ) {
             if let Some(sp) = self.tcx.hir().span_if_local(*def_id) {
@@ -4453,7 +4453,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 let ty = AstConv::ast_ty_to_ty(self, ty);
                 debug!("suggest_missing_return_type: return type {:?}", ty);
                 debug!("suggest_missing_return_type: expected type {:?}", ty);
-                if ty.sty == expected.sty {
+                if ty.kind == expected.kind {
                     err.span_label(sp, format!("expected `{}` because of return type",
                                                expected));
                     return true;
@@ -4699,7 +4699,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             let ty = self.impl_self_ty(span, impl_def_id).ty;
             let adt_def = ty.ty_adt_def();
 
-            match ty.sty {
+            match ty.kind {
                 ty::Adt(adt_def, substs) if adt_def.has_ctor() => {
                     let variant = adt_def.non_enum_variant();
                     let ctor_def_id = variant.ctor_def_id.unwrap();
@@ -4999,10 +4999,10 @@ pub fn check_bounds_are_used<'tcx>(tcx: TyCtxt<'tcx>, generics: &ty::Generics, t
     let mut types_used = vec![false; own_counts.types];
 
     for leaf_ty in ty.walk() {
-        if let ty::Param(ty::ParamTy { index, .. }) = leaf_ty.sty {
+        if let ty::Param(ty::ParamTy { index, .. }) = leaf_ty.kind {
             debug!("found use of ty param num {}", index);
             types_used[index as usize - own_counts.lifetimes] = true;
-        } else if let ty::Error = leaf_ty.sty {
+        } else if let ty::Error = leaf_ty.kind {
             // If there is already another error, do not emit
             // an error for not using a type parameter.
             assert!(tcx.sess.has_errors());
diff --git a/src/librustc_typeck/check/op.rs b/src/librustc_typeck/check/op.rs
index 956d04ff6229b..f9df2d1d848ff 100644
--- a/src/librustc_typeck/check/op.rs
+++ b/src/librustc_typeck/check/op.rs
@@ -202,7 +202,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             Ok(method) => {
                 let by_ref_binop = !op.node.is_by_value();
                 if is_assign == IsAssign::Yes || by_ref_binop {
-                    if let ty::Ref(region, _, mutbl) = method.sig.inputs()[0].sty {
+                    if let ty::Ref(region, _, mutbl) = method.sig.inputs()[0].kind {
                         let mutbl = match mutbl {
                             hir::MutImmutable => AutoBorrowMutability::Immutable,
                             hir::MutMutable => AutoBorrowMutability::Mutable {
@@ -219,7 +219,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                     }
                 }
                 if by_ref_binop {
-                    if let ty::Ref(region, _, mutbl) = method.sig.inputs()[1].sty {
+                    if let ty::Ref(region, _, mutbl) = method.sig.inputs()[1].kind {
                         let mutbl = match mutbl {
                             hir::MutImmutable => AutoBorrowMutability::Immutable,
                             hir::MutMutable => AutoBorrowMutability::Mutable {
@@ -268,7 +268,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                 op.node.as_str(), lhs_ty),
                             );
                             let mut suggested_deref = false;
-                            if let Ref(_, rty, _) = lhs_ty.sty {
+                            if let Ref(_, rty, _) = lhs_ty.kind {
                                 if {
                                     self.infcx.type_is_copy_modulo_regions(self.param_env,
                                                                            rty,
@@ -315,7 +315,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                     // This has nothing here because it means we did string
                                     // concatenation (e.g., "Hello " += "World!"). This means
                                     // we don't want the note in the else clause to be emitted
-                                } else if let ty::Param(_) = lhs_ty.sty {
+                                } else if let ty::Param(_) = lhs_ty.kind {
                                     // FIXME: point to span of param
                                     err.note(&format!(
                                         "`{}` might need a bound for `{}`",
@@ -358,7 +358,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                             }
 
                             let mut suggested_deref = false;
-                            if let Ref(_, rty, _) = lhs_ty.sty {
+                            if let Ref(_, rty, _) = lhs_ty.kind {
                                 if {
                                     self.infcx.type_is_copy_modulo_regions(self.param_env,
                                                                            rty,
@@ -406,7 +406,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                     // This has nothing here because it means we did string
                                     // concatenation (e.g., "Hello " + "World!"). This means
                                     // we don't want the note in the else clause to be emitted
-                                } else if let ty::Param(_) = lhs_ty.sty {
+                                } else if let ty::Param(_) = lhs_ty.kind {
                                     // FIXME: point to span of param
                                     err.note(&format!(
                                         "`{}` might need a bound for `{}`",
@@ -443,7 +443,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         is_assign: IsAssign,
     ) -> bool /* did we suggest to call a function because of missing parenthesis? */ {
         err.span_label(span, ty.to_string());
-        if let FnDef(def_id, _) = ty.sty {
+        if let FnDef(def_id, _) = ty.kind {
             let source_map = self.tcx.sess.source_map();
             let hir_id = match self.tcx.hir().as_local_hir_id(def_id) {
                 Some(hir_id) => hir_id,
@@ -461,7 +461,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 }
             };
 
-            let other_ty = if let FnDef(def_id, _) = other_ty.sty {
+            let other_ty = if let FnDef(def_id, _) = other_ty.kind {
                 let hir_id = match self.tcx.hir().as_local_hir_id(def_id) {
                     Some(hir_id) => hir_id,
                     None => return false,
@@ -531,10 +531,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         let is_std_string = |ty| &format!("{:?}", ty) == "std::string::String";
 
-        match (&lhs_ty.sty, &rhs_ty.sty) {
+        match (&lhs_ty.kind, &rhs_ty.kind) {
             (&Ref(_, l_ty, _), &Ref(_, r_ty, _)) // &str or &String + &str, &String or &&str
-                if (l_ty.sty == Str || is_std_string(l_ty)) && (
-                        r_ty.sty == Str || is_std_string(r_ty) ||
+                if (l_ty.kind == Str || is_std_string(l_ty)) && (
+                        r_ty.kind == Str || is_std_string(r_ty) ||
                         &format!("{:?}", rhs_ty) == "&&str"
                     ) =>
             {
@@ -568,7 +568,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                 true
             }
             (&Ref(_, l_ty, _), &Adt(..)) // Handle `&str` & `&String` + `String`
-                if (l_ty.sty == Str || is_std_string(l_ty)) && is_std_string(rhs_ty) =>
+                if (l_ty.kind == Str || is_std_string(l_ty)) && is_std_string(rhs_ty) =>
             {
                 err.span_label(
                     op.span,
@@ -626,12 +626,12 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
                                      op.as_str(), actual);
                     err.span_label(ex.span, format!("cannot apply unary \
                                                     operator `{}`", op.as_str()));
-                    match actual.sty {
+                    match actual.kind {
                         Uint(_) if op == hir::UnNeg => {
                             err.note("unsigned values cannot be negated");
                         },
                         Str | Never | Char | Tuple(_) | Array(_,_) => {},
-                        Ref(_, ref lty, _) if lty.sty == Str => {},
+                        Ref(_, ref lty, _) if lty.kind == Str => {},
                         _ => {
                             let missing_trait = match op {
                                 hir::UnNeg => "std::ops::Neg",
diff --git a/src/librustc_typeck/check/pat.rs b/src/librustc_typeck/check/pat.rs
index a2f7a8fe4febc..af3259b987a2e 100644
--- a/src/librustc_typeck/check/pat.rs
+++ b/src/librustc_typeck/check/pat.rs
@@ -213,7 +213,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             PatKind::Slice(..) => true,
             PatKind::Lit(ref lt) => {
                 let ty = self.check_expr(lt);
-                match ty.sty {
+                match ty.kind {
                     ty::Ref(..) => false,
                     _ => true,
                 }
@@ -262,7 +262,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         //
         // See the examples in `ui/match-defbm*.rs`.
         let mut pat_adjustments = vec![];
-        while let ty::Ref(_, inner_ty, inner_mutability) = expected.sty {
+        while let ty::Ref(_, inner_ty, inner_mutability) = expected.kind {
             debug!("inspecting {:?}", expected);
 
             debug!("current discriminant is Ref, inserting implicit deref");
@@ -309,8 +309,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         if let hir::ExprKind::Lit(ref lt) = lt.node {
             if let ast::LitKind::ByteStr(_) = lt.node {
                 let expected_ty = self.structurally_resolved_type(span, expected);
-                if let ty::Ref(_, r_ty, _) = expected_ty.sty {
-                    if let ty::Slice(_) = r_ty.sty {
+                if let ty::Ref(_, r_ty, _) = expected_ty.kind {
+                    if let ty::Slice(_) = r_ty.kind {
                         let tcx = self.tcx;
                         pat_ty = tcx.mk_imm_ref(
                             tcx.lifetimes.re_static,
@@ -507,7 +507,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     pub fn check_dereferencable(&self, span: Span, expected: Ty<'tcx>, inner: &Pat) -> bool {
         if let PatKind::Binding(..) = inner.node {
             if let Some(mt) = self.shallow_resolve(expected).builtin_deref(true) {
-                if let ty::Dynamic(..) = mt.ty.sty {
+                if let ty::Dynamic(..) = mt.ty.kind {
                     // This is "x = SomeTrait" being reduced from
                     // "let &x = &SomeTrait" or "let box x = Box<SomeTrait>", an error.
                     let type_str = self.ty_to_string(expected);
@@ -673,7 +673,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         if subpats.len() == variant.fields.len()
             || subpats.len() < variant.fields.len() && ddpos.is_some()
         {
-            let substs = match pat_ty.sty {
+            let substs = match pat_ty.kind {
                 ty::Adt(_, substs) => substs,
                 _ => bug!("unexpected pattern type {:?}", pat_ty),
             };
@@ -727,10 +727,10 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         // More generally, the expected type wants a tuple variant with one field of an
         // N-arity-tuple, e.g., `V_i((p_0, .., p_N))`. Meanwhile, the user supplied a pattern
         // with the subpatterns directly in the tuple variant pattern, e.g., `V_i(p_0, .., p_N)`.
-        let missing_parenthesis = match expected.sty {
+        let missing_parenthesis = match expected.kind {
             ty::Adt(_, substs) if fields.len() == 1 => {
                 let field_ty = fields[0].ty(self.tcx, substs);
-                match field_ty.sty {
+                match field_ty.kind {
                     ty::Tuple(_) => field_ty.tuple_fields().count() == subpats.len(),
                     _ => false,
                 }
@@ -790,7 +790,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         let mut expected_len = elements.len();
         if ddpos.is_some() {
             // Require known type only when `..` is present.
-            if let ty::Tuple(ref tys) = self.structurally_resolved_type(span, expected).sty {
+            if let ty::Tuple(ref tys) = self.structurally_resolved_type(span, expected).kind {
                 expected_len = tys.len();
             }
         }
@@ -837,7 +837,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     ) -> bool {
         let tcx = self.tcx;
 
-        let (substs, adt) = match adt_ty.sty {
+        let (substs, adt) = match adt_ty.kind {
             ty::Adt(adt, substs) => (substs, adt),
             _ => span_bug!(span, "struct pattern is not an ADT")
         };
@@ -1075,7 +1075,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             // to avoid creating needless variables. This also helps with
             // the bad  interactions of the given hack detailed in (note_1).
             debug!("check_pat_ref: expected={:?}", expected);
-            match expected.sty {
+            match expected.kind {
                 ty::Ref(_, r_ty, r_mutbl) if r_mutbl == mutbl => (expected, r_ty),
                 _ => {
                     let inner_ty = self.next_ty_var(
@@ -1123,7 +1123,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     ) -> Ty<'tcx> {
         let tcx = self.tcx;
         let expected_ty = self.structurally_resolved_type(span, expected);
-        let (inner_ty, slice_ty) = match expected_ty.sty {
+        let (inner_ty, slice_ty) = match expected_ty.kind {
             ty::Array(inner_ty, size) => {
                 let slice_ty = if let Some(size) = size.try_eval_usize(tcx, self.param_env) {
                     let min_len = before.len() as u64 + after.len() as u64;
@@ -1212,8 +1212,8 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             "expected an array or slice, found `{}`",
             expected_ty
         );
-        if let ty::Ref(_, ty, _) = expected_ty.sty {
-            if let ty::Array(..) | ty::Slice(..) = ty.sty {
+        if let ty::Ref(_, ty, _) = expected_ty.kind {
+            if let ty::Array(..) | ty::Slice(..) = ty.kind {
                 err.help("the semantics of slice patterns changed recently; see issue #62254");
             }
         }
diff --git a/src/librustc_typeck/check/regionck.rs b/src/librustc_typeck/check/regionck.rs
index 6fa8a016b5458..ac9f9f1ea25b1 100644
--- a/src/librustc_typeck/check/regionck.rs
+++ b/src/librustc_typeck/check/regionck.rs
@@ -621,7 +621,7 @@ impl<'a, 'tcx> Visitor<'tcx> for RegionCtxt<'a, 'tcx> {
                 // For overloaded derefs, base_ty is the input to `Deref::deref`,
                 // but it's a reference type uing the same region as the output.
                 let base_ty = self.resolve_expr_type_adjusted(base);
-                if let ty::Ref(r_ptr, _, _) = base_ty.sty {
+                if let ty::Ref(r_ptr, _, _) = base_ty.kind {
                     self.mk_subregion_due_to_dereference(expr.span, expr_region, r_ptr);
                 }
 
@@ -720,7 +720,7 @@ impl<'a, 'tcx> RegionCtxt<'a, 'tcx> {
 
     fn walk_cast(&mut self, cast_expr: &hir::Expr, from_ty: Ty<'tcx>, to_ty: Ty<'tcx>) {
         debug!("walk_cast(from_ty={:?}, to_ty={:?})", from_ty, to_ty);
-        match (&from_ty.sty, &to_ty.sty) {
+        match (&from_ty.kind, &to_ty.kind) {
             /*From:*/
             (&ty::Ref(from_r, from_ty, _), /*To:  */ &ty::Ref(to_r, to_ty, _)) => {
                 // Target cannot outlive source, naturally.
@@ -754,7 +754,7 @@ impl<'a, 'tcx> RegionCtxt<'a, 'tcx> {
 
     fn constrain_callee(&mut self, callee_expr: &hir::Expr) {
         let callee_ty = self.resolve_node_type(callee_expr.hir_id);
-        match callee_ty.sty {
+        match callee_ty.kind {
             ty::FnDef(..) | ty::FnPtr(_) => {}
             _ => {
                 // this should not happen, but it does if the program is
@@ -966,8 +966,8 @@ impl<'a, 'tcx> RegionCtxt<'a, 'tcx> {
             id: index_expr.hir_id.local_id,
             data: region::ScopeData::Node,
         });
-        if let ty::Ref(r_ptr, r_ty, _) = indexed_ty.sty {
-            match r_ty.sty {
+        if let ty::Ref(r_ptr, r_ty, _) = indexed_ty.kind {
+            match r_ty.kind {
                 ty::Slice(_) | ty::Str => {
                     self.sub_regions(
                         infer::IndexSlice(index_expr.span),
@@ -1160,7 +1160,7 @@ impl<'a, 'tcx> RegionCtxt<'a, 'tcx> {
         );
 
         let rptr_ty = self.resolve_node_type(id);
-        if let ty::Ref(r, _, _) = rptr_ty.sty {
+        if let ty::Ref(r, _, _) = rptr_ty.kind {
             debug!("rptr_ty={}", rptr_ty);
             self.link_region(span, r, ty::BorrowKind::from_mutbl(mutbl), cmt_borrowed);
         }
diff --git a/src/librustc_typeck/check/upvar.rs b/src/librustc_typeck/check/upvar.rs
index 155cabb27a92f..d57fec9947db1 100644
--- a/src/librustc_typeck/check/upvar.rs
+++ b/src/librustc_typeck/check/upvar.rs
@@ -95,7 +95,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
 
         // Extract the type of the closure.
         let ty = self.node_ty(closure_hir_id);
-        let (closure_def_id, substs) = match ty.sty {
+        let (closure_def_id, substs) = match ty.kind {
             ty::Closure(def_id, substs) => (def_id, UpvarSubsts::Closure(substs)),
             ty::Generator(def_id, substs, _) => (def_id, UpvarSubsts::Generator(substs)),
             ty::Error => {
diff --git a/src/librustc_typeck/check/wfcheck.rs b/src/librustc_typeck/check/wfcheck.rs
index 265d0676fa8d1..a5864a32d2c54 100644
--- a/src/librustc_typeck/check/wfcheck.rs
+++ b/src/librustc_typeck/check/wfcheck.rs
@@ -94,20 +94,27 @@ pub fn check_item_well_formed(tcx: TyCtxt<'_>, def_id: DefId) {
         //
         // won't be allowed unless there's an *explicit* implementation of `Send`
         // for `T`
-        hir::ItemKind::Impl(_, polarity, defaultness, _, ref trait_ref, ref self_ty, _) => {
+        hir::ItemKind::Impl(_, _, defaultness, _, ref trait_ref, ref self_ty, _) => {
             let is_auto = tcx.impl_trait_ref(tcx.hir().local_def_id(item.hir_id))
-                                .map_or(false, |trait_ref| tcx.trait_is_auto(trait_ref.def_id));
+                .map_or(false, |trait_ref| tcx.trait_is_auto(trait_ref.def_id));
+            let polarity = tcx.impl_polarity(def_id);
             if let (hir::Defaultness::Default { .. }, true) = (defaultness, is_auto) {
                 tcx.sess.span_err(item.span, "impls of auto traits cannot be default");
             }
-            if polarity == hir::ImplPolarity::Positive {
-                check_impl(tcx, item, self_ty, trait_ref);
-            } else {
-                // FIXME(#27579): what amount of WF checking do we need for neg impls?
-                if trait_ref.is_some() && !is_auto {
-                    span_err!(tcx.sess, item.span, E0192,
-                              "negative impls are only allowed for \
-                               auto traits (e.g., `Send` and `Sync`)")
+            match polarity {
+                ty::ImplPolarity::Positive => {
+                    check_impl(tcx, item, self_ty, trait_ref);
+                }
+                ty::ImplPolarity::Negative => {
+                    // FIXME(#27579): what amount of WF checking do we need for neg impls?
+                    if trait_ref.is_some() && !is_auto {
+                        span_err!(tcx.sess, item.span, E0192,
+                                  "negative impls are only allowed for \
+                                   auto traits (e.g., `Send` and `Sync`)")
+                    }
+                }
+                ty::ImplPolarity::Reservation => {
+                    // FIXME: what amount of WF checking do we need for reservation impls?
                 }
             }
         }
@@ -366,7 +373,7 @@ fn check_item_type(
         let mut forbid_unsized = true;
         if allow_foreign_ty {
             let tail = fcx.tcx.struct_tail_erasing_lifetimes(item_ty, fcx.param_env);
-            if let ty::Foreign(_) = tail.sty {
+            if let ty::Foreign(_) = tail.kind {
                 forbid_unsized = false;
             }
         }
@@ -398,16 +405,19 @@ fn check_impl<'tcx>(
 
         match *ast_trait_ref {
             Some(ref ast_trait_ref) => {
+                // `#[rustc_reservation_impl]` impls are not real impls and
+                // therefore don't need to be WF (the trait's `Self: Trait` predicate
+                // won't hold).
                 let trait_ref = fcx.tcx.impl_trait_ref(item_def_id).unwrap();
                 let trait_ref =
                     fcx.normalize_associated_types_in(
                         ast_trait_ref.path.span, &trait_ref);
                 let obligations =
                     ty::wf::trait_obligations(fcx,
-                                                fcx.param_env,
-                                                fcx.body_id,
-                                                &trait_ref,
-                                                ast_trait_ref.path.span);
+                                              fcx.param_env,
+                                              fcx.body_id,
+                                              &trait_ref,
+                                              ast_trait_ref.path.span);
                 for obligation in obligations {
                     fcx.register_predicate(obligation);
                 }
@@ -511,7 +521,7 @@ fn check_where_clauses<'tcx, 'fcx>(
         struct CountParams { params: FxHashSet<u32> }
         impl<'tcx> ty::fold::TypeVisitor<'tcx> for CountParams {
             fn visit_ty(&mut self, t: Ty<'tcx>) -> bool {
-                if let ty::Param(param) = t.sty {
+                if let ty::Param(param) = t.kind {
                     self.params.insert(param.index);
                 }
                 t.super_visit_with(self)
@@ -635,7 +645,7 @@ fn check_opaque_types<'fcx, 'tcx>(
     ty.fold_with(&mut ty::fold::BottomUpFolder {
         tcx: fcx.tcx,
         ty_op: |ty| {
-            if let ty::Opaque(def_id, substs) = ty.sty {
+            if let ty::Opaque(def_id, substs) = ty.kind {
                 trace!("check_opaque_types: opaque_ty, {:?}, {:?}", def_id, substs);
                 let generics = tcx.generics_of(def_id);
                 // Only check named `impl Trait` types defined in this crate.
@@ -646,7 +656,7 @@ fn check_opaque_types<'fcx, 'tcx>(
                         let mut seen: FxHashMap<_, Vec<_>> = FxHashMap::default();
                         for (subst, param) in substs.iter().zip(&generics.params) {
                             match subst.unpack() {
-                                ty::subst::UnpackedKind::Type(ty) => match ty.sty {
+                                ty::subst::UnpackedKind::Type(ty) => match ty.kind {
                                     ty::Param(..) => {}
                                     // Prevent `fn foo() -> Foo<u32>` from being defining.
                                     _ => {
diff --git a/src/librustc_typeck/check/writeback.rs b/src/librustc_typeck/check/writeback.rs
index 1cc71ea5649de..f3ee64e9d1368 100644
--- a/src/librustc_typeck/check/writeback.rs
+++ b/src/librustc_typeck/check/writeback.rs
@@ -190,7 +190,7 @@ impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> {
             let mut tables = self.fcx.tables.borrow_mut();
 
             // All valid indexing looks like this; might encounter non-valid indexes at this point
-            if let ty::Ref(_, base_ty, _) = tables.expr_ty_adjusted(&base).sty {
+            if let ty::Ref(_, base_ty, _) = tables.expr_ty_adjusted(&base).kind {
                 let index_ty = tables.expr_ty_adjusted(&index);
                 let index_ty = self.fcx.resolve_vars_if_possible(&index_ty);
 
@@ -454,7 +454,7 @@ impl<'cx, 'tcx> WritebackCx<'cx, 'tcx> {
 
             let mut skip_add = false;
 
-            if let ty::Opaque(defin_ty_def_id, _substs) = definition_ty.sty {
+            if let ty::Opaque(defin_ty_def_id, _substs) = definition_ty.kind {
                 if def_id == defin_ty_def_id {
                     debug!("Skipping adding concrete definition for opaque type {:?} {:?}",
                            opaque_defn, defin_ty_def_id);
diff --git a/src/librustc_typeck/coherence/builtin.rs b/src/librustc_typeck/coherence/builtin.rs
index a95b9a03dcf77..9054c2b80102a 100644
--- a/src/librustc_typeck/coherence/builtin.rs
+++ b/src/librustc_typeck/coherence/builtin.rs
@@ -47,7 +47,7 @@ impl<'tcx> Checker<'tcx> {
 }
 
 fn visit_implementation_of_drop(tcx: TyCtxt<'_>, impl_did: DefId) {
-    if let ty::Adt(..) = tcx.type_of(impl_did).sty {
+    if let ty::Adt(..) = tcx.type_of(impl_did).kind {
         /* do nothing */
     } else {
         // Destructors only work on nominal types.
@@ -186,7 +186,7 @@ fn visit_implementation_of_dispatch_from_dyn(tcx: TyCtxt<'_>, impl_did: DefId) {
             let cause = ObligationCause::misc(span, impl_hir_id);
 
             use ty::TyKind::*;
-            match (&source.sty, &target.sty) {
+            match (&source.kind, &target.kind) {
                 (&Ref(r_a, _, mutbl_a), Ref(r_b, _, mutbl_b))
                     if infcx.at(&cause, param_env).eq(r_a, r_b).is_ok()
                     && mutbl_a == *mutbl_b => (),
@@ -367,7 +367,7 @@ pub fn coerce_unsized_info<'tcx>(gcx: TyCtxt<'tcx>, impl_did: DefId) -> CoerceUn
             }
             (mt_a.ty, mt_b.ty, unsize_trait, None)
         };
-        let (source, target, trait_def_id, kind) = match (&source.sty, &target.sty) {
+        let (source, target, trait_def_id, kind) = match (&source.kind, &target.kind) {
             (&ty::Ref(r_a, ty_a, mutbl_a), &ty::Ref(r_b, ty_b, mutbl_b)) => {
                 infcx.sub_regions(infer::RelateObjectBound(span), r_b, r_a);
                 let mt_a = ty::TypeAndMut { ty: ty_a, mutbl: mutbl_a };
diff --git a/src/librustc_typeck/coherence/inherent_impls.rs b/src/librustc_typeck/coherence/inherent_impls.rs
index e7c2126cfd727..d2651317da948 100644
--- a/src/librustc_typeck/coherence/inherent_impls.rs
+++ b/src/librustc_typeck/coherence/inherent_impls.rs
@@ -57,7 +57,7 @@ impl ItemLikeVisitor<'v> for InherentCollect<'tcx> {
         let def_id = self.tcx.hir().local_def_id(item.hir_id);
         let self_ty = self.tcx.type_of(def_id);
         let lang_items = self.tcx.lang_items();
-        match self_ty.sty {
+        match self_ty.kind {
             ty::Adt(def, _) => {
                 self.check_def_id(item, def.did);
             }
diff --git a/src/librustc_typeck/coherence/mod.rs b/src/librustc_typeck/coherence/mod.rs
index 1d0e433f07b3a..a44c475e0f8a9 100644
--- a/src/librustc_typeck/coherence/mod.rs
+++ b/src/librustc_typeck/coherence/mod.rs
@@ -167,7 +167,7 @@ fn check_impl_overlap<'tcx>(tcx: TyCtxt<'tcx>, hir_id: HirId) {
     tcx.specialization_graph_of(trait_def_id);
 
     // check for overlap with the automatic `impl Trait for Trait`
-    if let ty::Dynamic(ref data, ..) = trait_ref.self_ty().sty {
+    if let ty::Dynamic(ref data, ..) = trait_ref.self_ty().kind {
         // This is something like impl Trait1 for Trait2. Illegal
         // if Trait1 is a supertrait of Trait2 or Trait2 is not object safe.
 
diff --git a/src/librustc_typeck/coherence/orphan.rs b/src/librustc_typeck/coherence/orphan.rs
index 299e18337bd30..8969bf894e0f6 100644
--- a/src/librustc_typeck/coherence/orphan.rs
+++ b/src/librustc_typeck/coherence/orphan.rs
@@ -102,7 +102,7 @@ impl ItemLikeVisitor<'v> for OrphanChecker<'tcx> {
             if self.tcx.trait_is_auto(trait_def_id) &&
                !trait_def_id.is_local() {
                 let self_ty = trait_ref.self_ty();
-                let opt_self_def_id = match self_ty.sty {
+                let opt_self_def_id = match self_ty.kind {
                     ty::Adt(self_def, _) => Some(self_def.did),
                     ty::Foreign(did) => Some(did),
                     _ => None,
diff --git a/src/librustc_typeck/collect.rs b/src/librustc_typeck/collect.rs
index e6e0cb88fbd23..d1643cbb87aba 100644
--- a/src/librustc_typeck/collect.rs
+++ b/src/librustc_typeck/collect.rs
@@ -1581,7 +1581,7 @@ fn find_opaque_ty_constraints(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
                 // their positions.
                 for (idx, subst) in substs.iter().enumerate() {
                     if let UnpackedKind::Type(ty) = subst.unpack() {
-                        if let ty::Param(p) = ty.sty {
+                        if let ty::Param(p) = ty.kind {
                             if index_map.insert(p, idx).is_some() {
                                 // There was already an entry for `p`, meaning a generic parameter
                                 // was used twice.
@@ -1611,11 +1611,11 @@ fn find_opaque_ty_constraints(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
                 let indices = concrete_type
                     .subst(self.tcx, substs)
                     .walk()
-                    .filter_map(|t| match &t.sty {
+                    .filter_map(|t| match &t.kind {
                         ty::Param(p) => Some(*index_map.get(p).unwrap()),
                         _ => None,
                     }).collect();
-                let is_param = |ty: Ty<'_>| match ty.sty {
+                let is_param = |ty: Ty<'_>| match ty.kind {
                     ty::Param(_) => true,
                     _ => false,
                 };
@@ -1627,7 +1627,7 @@ fn find_opaque_ty_constraints(tcx: TyCtxt<'_>, def_id: DefId) -> Ty<'_> {
                 } else if let Some((prev_span, prev_ty, ref prev_indices)) = self.found {
                     let mut ty = concrete_type.walk().fuse();
                     let mut p_ty = prev_ty.walk().fuse();
-                    let iter_eq = (&mut ty).zip(&mut p_ty).all(|(t, p)| match (&t.sty, &p.sty) {
+                    let iter_eq = (&mut ty).zip(&mut p_ty).all(|(t, p)| match (&t.kind, &p.kind) {
                         // Type parameters are equal to any other type parameter for the purpose of
                         // concrete type equality, as it is possible to obtain the same type just
                         // by passing matching parameters to a function.
@@ -1889,10 +1889,30 @@ fn impl_trait_ref(tcx: TyCtxt<'_>, def_id: DefId) -> Option<ty::TraitRef<'_>> {
     }
 }
 
-fn impl_polarity(tcx: TyCtxt<'_>, def_id: DefId) -> hir::ImplPolarity {
+fn impl_polarity(tcx: TyCtxt<'_>, def_id: DefId) -> ty::ImplPolarity {
     let hir_id = tcx.hir().as_local_hir_id(def_id).unwrap();
-    match tcx.hir().expect_item(hir_id).node {
-        hir::ItemKind::Impl(_, polarity, ..) => polarity,
+    let is_rustc_reservation = tcx.has_attr(def_id, sym::rustc_reservation_impl);
+    let item = tcx.hir().expect_item(hir_id);
+    match &item.node {
+        hir::ItemKind::Impl(_, hir::ImplPolarity::Negative, ..) => {
+            if is_rustc_reservation {
+                tcx.sess.span_err(item.span, "reservation impls can't be negative");
+            }
+            ty::ImplPolarity::Negative
+        }
+        hir::ItemKind::Impl(_, hir::ImplPolarity::Positive, _, _, None, _, _) => {
+            if is_rustc_reservation {
+                tcx.sess.span_err(item.span, "reservation impls can't be inherent");
+            }
+            ty::ImplPolarity::Positive
+        }
+        hir::ItemKind::Impl(_, hir::ImplPolarity::Positive, _, _, Some(_tr), _, _) => {
+            if is_rustc_reservation {
+                ty::ImplPolarity::Reservation
+            } else {
+                ty::ImplPolarity::Positive
+            }
+        }
         ref item => bug!("impl_polarity: {:?} not an impl", item),
     }
 }
@@ -2198,7 +2218,7 @@ fn explicit_predicates_of(
                 // That way, `where Ty:` is not a complete noop (see #53696) and `Ty`
                 // is still checked for WF.
                 if bound_pred.bounds.is_empty() {
-                    if let ty::Param(_) = ty.sty {
+                    if let ty::Param(_) = ty.kind {
                         // This is a `where T:`, which can be in the HIR from the
                         // transformation that moves `?Sized` to `T`'s declaration.
                         // We can skip the predicate because type parameters are
diff --git a/src/librustc_typeck/constrained_generic_params.rs b/src/librustc_typeck/constrained_generic_params.rs
index dd44f86717fe5..31476eb731798 100644
--- a/src/librustc_typeck/constrained_generic_params.rs
+++ b/src/librustc_typeck/constrained_generic_params.rs
@@ -55,7 +55,7 @@ struct ParameterCollector {
 
 impl<'tcx> TypeVisitor<'tcx> for ParameterCollector {
     fn visit_ty(&mut self, t: Ty<'tcx>) -> bool {
-        match t.sty {
+        match t.kind {
             ty::Projection(..) | ty::Opaque(..) if !self.include_nonconstraining => {
                 // projections are not injective
                 return false;
diff --git a/src/librustc_typeck/lib.rs b/src/librustc_typeck/lib.rs
index e97d6db5db08c..dbff1e91617e5 100644
--- a/src/librustc_typeck/lib.rs
+++ b/src/librustc_typeck/lib.rs
@@ -159,7 +159,7 @@ fn check_main_fn_ty(tcx: TyCtxt<'_>, main_def_id: DefId) {
     let main_id = tcx.hir().as_local_hir_id(main_def_id).unwrap();
     let main_span = tcx.def_span(main_def_id);
     let main_t = tcx.type_of(main_def_id);
-    match main_t.sty {
+    match main_t.kind {
         ty::FnDef(..) => {
             if let Some(Node::Item(it)) = tcx.hir().find(main_id) {
                 if let hir::ItemKind::Fn(.., ref generics, _) = it.node {
@@ -224,7 +224,7 @@ fn check_start_fn_ty(tcx: TyCtxt<'_>, start_def_id: DefId) {
     let start_id = tcx.hir().as_local_hir_id(start_def_id).unwrap();
     let start_span = tcx.def_span(start_def_id);
     let start_t = tcx.type_of(start_def_id);
-    match start_t.sty {
+    match start_t.kind {
         ty::FnDef(..) => {
             if let Some(Node::Item(it)) = tcx.hir().find(start_id) {
                 if let hir::ItemKind::Fn(.., ref generics, _) = it.node {
diff --git a/src/librustc_typeck/outlives/implicit_infer.rs b/src/librustc_typeck/outlives/implicit_infer.rs
index 644d723ded5d9..f8d92f625c301 100644
--- a/src/librustc_typeck/outlives/implicit_infer.rs
+++ b/src/librustc_typeck/outlives/implicit_infer.rs
@@ -123,7 +123,7 @@ fn insert_required_predicates_to_be_wf<'tcx>(
     explicit_map: &mut ExplicitPredicatesMap<'tcx>,
 ) {
     for ty in field_ty.walk() {
-        match ty.sty {
+        match ty.kind {
             // The field is of type &'a T which means that we will have
             // a predicate requirement of T: 'a (T outlives 'a).
             //
diff --git a/src/librustc_typeck/variance/constraints.rs b/src/librustc_typeck/variance/constraints.rs
index 7ed9d6606f646..16d5fde815f6a 100644
--- a/src/librustc_typeck/variance/constraints.rs
+++ b/src/librustc_typeck/variance/constraints.rs
@@ -140,7 +140,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
         let id = tcx.hir().as_local_hir_id(def_id).unwrap();
         let inferred_start = self.terms_cx.inferred_starts[&id];
         let current_item = &CurrentItem { inferred_start };
-        match tcx.type_of(def_id).sty {
+        match tcx.type_of(def_id).kind {
             ty::Adt(def, _) => {
                 // Not entirely obvious: constraints on structs/enums do not
                 // affect the variance of their type parameters. See discussion
@@ -256,7 +256,7 @@ impl<'a, 'tcx> ConstraintContext<'a, 'tcx> {
                ty,
                variance);
 
-        match ty.sty {
+        match ty.kind {
             ty::Bool | ty::Char | ty::Int(_) | ty::Uint(_) | ty::Float(_) |
             ty::Str | ty::Never | ty::Foreign(..) => {
                 // leaf type -- noop
diff --git a/src/librustc_typeck/variance/solve.rs b/src/librustc_typeck/variance/solve.rs
index 1176c5ebb3d30..fbd476ef832c4 100644
--- a/src/librustc_typeck/variance/solve.rs
+++ b/src/librustc_typeck/variance/solve.rs
@@ -109,7 +109,7 @@ impl<'a, 'tcx> SolveContext<'a, 'tcx> {
             self.enforce_const_invariance(generics, variances);
 
             // Functions are permitted to have unused generic parameters: make those invariant.
-            if let ty::FnDef(..) = tcx.type_of(def_id).sty {
+            if let ty::FnDef(..) = tcx.type_of(def_id).kind {
                 for variance in variances.iter_mut() {
                     if *variance == ty::Bivariant {
                         *variance = ty::Invariant;
diff --git a/src/librustdoc/clean/blanket_impl.rs b/src/librustdoc/clean/blanket_impl.rs
index 4cd1cc1a1cf50..afed11e7fab26 100644
--- a/src/librustdoc/clean/blanket_impl.rs
+++ b/src/librustdoc/clean/blanket_impl.rs
@@ -41,7 +41,7 @@ impl<'a, 'tcx> BlanketImplFinder<'a, 'tcx> {
                         trait_def_id, impl_def_id);
                 let trait_ref = self.cx.tcx.impl_trait_ref(impl_def_id).unwrap();
                 let may_apply = self.cx.tcx.infer_ctxt().enter(|infcx| {
-                    match trait_ref.self_ty().sty {
+                    match trait_ref.self_ty().kind {
                         ty::Param(_) => {},
                         _ => return false,
                     }
diff --git a/src/librustdoc/clean/mod.rs b/src/librustdoc/clean/mod.rs
index d1a9b740d62ab..3972d77385dc8 100644
--- a/src/librustdoc/clean/mod.rs
+++ b/src/librustdoc/clean/mod.rs
@@ -1108,7 +1108,7 @@ fn external_generic_args(
             None
         }
         UnpackedKind::Type(ty) => {
-            ty_sty = Some(&ty.sty);
+            ty_sty = Some(&ty.kind);
             Some(GenericArg::Type(ty.clean(cx)))
         }
         UnpackedKind::Const(ct) => Some(GenericArg::Const(ct.clean(cx))),
@@ -1124,7 +1124,7 @@ fn external_generic_args(
             };
             let output = None;
             // FIXME(#20299) return type comes from a projection now
-            // match types[1].sty {
+            // match types[1].kind {
             //     ty::Tuple(ref v) if v.is_empty() => None, // -> ()
             //     _ => Some(types[1].clean(cx))
             // };
@@ -1162,9 +1162,9 @@ impl<'a, 'tcx> Clean<GenericBound> for (&'a ty::TraitRef<'tcx>, Vec<TypeBinding>
         // collect any late bound regions
         let mut late_bounds = vec![];
         for ty_s in trait_ref.input_types().skip(1) {
-            if let ty::Tuple(ts) = ty_s.sty {
+            if let ty::Tuple(ts) = ty_s.kind {
                 for &ty_s in ts {
-                    if let ty::Ref(ref reg, _, _) = ty_s.expect_ty().sty {
+                    if let ty::Ref(ref reg, _, _) = ty_s.expect_ty().kind {
                         if let &ty::RegionKind::ReLateBound(..) = *reg {
                             debug!("  hit an ReLateBound {:?}", reg);
                             if let Some(Lifetime(name)) = reg.clean(cx) {
@@ -1705,15 +1705,15 @@ impl<'a, 'tcx> Clean<Generics> for (&'a ty::Generics,
                 let mut projection = None;
                 let param_idx = (|| {
                     if let Some(trait_ref) = p.to_opt_poly_trait_ref() {
-                        if let ty::Param(param) = trait_ref.self_ty().sty {
+                        if let ty::Param(param) = trait_ref.self_ty().kind {
                             return Some(param.index);
                         }
                     } else if let Some(outlives) = p.to_opt_type_outlives() {
-                        if let ty::Param(param) = outlives.skip_binder().0.sty {
+                        if let ty::Param(param) = outlives.skip_binder().0.kind {
                             return Some(param.index);
                         }
                     } else if let ty::Predicate::Projection(p) = p {
-                        if let ty::Param(param) = p.skip_binder().projection_ty.self_ty().sty {
+                        if let ty::Param(param) = p.skip_binder().projection_ty.self_ty().kind {
                             projection = Some(p);
                             return Some(param.index);
                         }
@@ -2380,7 +2380,7 @@ impl Clean<Item> for ty::AssocItem {
                     let self_arg_ty = *sig.input(0).skip_binder();
                     if self_arg_ty == self_ty {
                         decl.inputs.values[0].type_ = Generic(String::from("Self"));
-                    } else if let ty::Ref(_, ty, _) = self_arg_ty.sty {
+                    } else if let ty::Ref(_, ty, _) = self_arg_ty.kind {
                         if ty == self_ty {
                             match decl.inputs.values[0].type_ {
                                 BorrowedRef{ref mut type_, ..} => {
@@ -3000,7 +3000,7 @@ impl Clean<Type> for hir::Ty {
             TyKind::Path(hir::QPath::TypeRelative(ref qself, ref segment)) => {
                 let mut res = Res::Err;
                 let ty = hir_ty_to_ty(cx.tcx, self);
-                if let ty::Projection(proj) = ty.sty {
+                if let ty::Projection(proj) = ty.kind {
                     res = Res::Def(DefKind::Trait, proj.trait_ref(cx.tcx).def_id);
                 }
                 let trait_path = hir::Path {
@@ -3040,7 +3040,7 @@ impl Clean<Type> for hir::Ty {
 impl<'tcx> Clean<Type> for Ty<'tcx> {
     fn clean(&self, cx: &DocContext<'_>) -> Type {
         debug!("cleaning type: {:?}", self);
-        match self.sty {
+        match self.kind {
             ty::Never => Never,
             ty::Bool => Primitive(PrimitiveType::Bool),
             ty::Char => Primitive(PrimitiveType::Char),
@@ -3855,11 +3855,13 @@ pub enum ImplPolarity {
     Negative,
 }
 
-impl Clean<ImplPolarity> for hir::ImplPolarity {
+impl Clean<ImplPolarity> for ty::ImplPolarity {
     fn clean(&self, _: &DocContext<'_>) -> ImplPolarity {
         match self {
-            &hir::ImplPolarity::Positive => ImplPolarity::Positive,
-            &hir::ImplPolarity::Negative => ImplPolarity::Negative,
+            &ty::ImplPolarity::Positive |
+            // FIXME: do we want to do something else here?
+            &ty::ImplPolarity::Reservation => ImplPolarity::Positive,
+            &ty::ImplPolarity::Negative => ImplPolarity::Negative,
         }
     }
 }
@@ -3891,6 +3893,7 @@ impl Clean<Vec<Item>> for doctree::Impl<'_> {
         let mut ret = Vec::new();
         let trait_ = self.trait_.clean(cx);
         let items = self.items.iter().map(|ii| ii.clean(cx)).collect::<Vec<_>>();
+        let def_id = cx.tcx.hir().local_def_id(self.id);
 
         // If this impl block is an implementation of the Deref trait, then we
         // need to try inlining the target's inherent impl blocks as well.
@@ -3909,7 +3912,7 @@ impl Clean<Vec<Item>> for doctree::Impl<'_> {
             name: None,
             attrs: self.attrs.clean(cx),
             source: self.whence.clean(cx),
-            def_id: cx.tcx.hir().local_def_id(self.id),
+            def_id,
             visibility: self.vis.clean(cx),
             stability: cx.stability(self.id).clean(cx),
             deprecation: cx.deprecation(self.id).clean(cx),
@@ -3920,7 +3923,7 @@ impl Clean<Vec<Item>> for doctree::Impl<'_> {
                 trait_,
                 for_: self.for_.clean(cx),
                 items,
-                polarity: Some(self.polarity.clean(cx)),
+                polarity: Some(cx.tcx.impl_polarity(def_id).clean(cx)),
                 synthetic: false,
                 blanket_impl: None,
             })
diff --git a/src/librustdoc/passes/collect_intra_doc_links.rs b/src/librustdoc/passes/collect_intra_doc_links.rs
index b67f39d328015..9186ed514202f 100644
--- a/src/librustdoc/passes/collect_intra_doc_links.rs
+++ b/src/librustdoc/passes/collect_intra_doc_links.rs
@@ -155,7 +155,7 @@ impl<'a, 'tcx> LinkCollector<'a, 'tcx> {
                         };
                         Ok((ty_res, Some(format!("{}.{}", out, item_name))))
                     } else {
-                        match cx.tcx.type_of(did).sty {
+                        match cx.tcx.type_of(did).kind {
                             ty::Adt(def, _) => {
                                 if let Some(item) = if def.is_enum() {
                                     def.all_fields().find(|item| item.ident.name == item_name)
diff --git a/src/libstd/sys/unix/process/mod.rs b/src/libstd/sys/unix/process/mod.rs
index 056a20345f404..553e980f08e97 100644
--- a/src/libstd/sys/unix/process/mod.rs
+++ b/src/libstd/sys/unix/process/mod.rs
@@ -1,5 +1,5 @@
-pub use self::process_common::{Command, ExitStatus, ExitCode, Stdio, StdioPipes};
-pub use self::process_inner::Process;
+pub use self::process_common::{Command, ExitCode, Stdio, StdioPipes};
+pub use self::process_inner::{ExitStatus, Process};
 pub use crate::ffi::OsString as EnvKey;
 
 mod process_common;
diff --git a/src/libstd/sys/unix/process/process_common.rs b/src/libstd/sys/unix/process/process_common.rs
index 713d308555956..4edd2ebf8c598 100644
--- a/src/libstd/sys/unix/process/process_common.rs
+++ b/src/libstd/sys/unix/process/process_common.rs
@@ -393,57 +393,6 @@ impl fmt::Debug for Command {
     }
 }
 
-/// Unix exit statuses
-#[derive(PartialEq, Eq, Clone, Copy, Debug)]
-pub struct ExitStatus(c_int);
-
-impl ExitStatus {
-    pub fn new(status: c_int) -> ExitStatus {
-        ExitStatus(status)
-    }
-
-    fn exited(&self) -> bool {
-        unsafe { libc::WIFEXITED(self.0) }
-    }
-
-    pub fn success(&self) -> bool {
-        self.code() == Some(0)
-    }
-
-    pub fn code(&self) -> Option<i32> {
-        if self.exited() {
-            Some(unsafe { libc::WEXITSTATUS(self.0) })
-        } else {
-            None
-        }
-    }
-
-    pub fn signal(&self) -> Option<i32> {
-        if !self.exited() {
-            Some(unsafe { libc::WTERMSIG(self.0) })
-        } else {
-            None
-        }
-    }
-}
-
-impl From<c_int> for ExitStatus {
-    fn from(a: c_int) -> ExitStatus {
-        ExitStatus(a)
-    }
-}
-
-impl fmt::Display for ExitStatus {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        if let Some(code) = self.code() {
-            write!(f, "exit code: {}", code)
-        } else {
-            let signal = self.signal().unwrap();
-            write!(f, "signal: {}", signal)
-        }
-    }
-}
-
 #[derive(PartialEq, Eq, Clone, Copy, Debug)]
 pub struct ExitCode(u8);
 
diff --git a/src/libstd/sys/unix/process/process_fuchsia.rs b/src/libstd/sys/unix/process/process_fuchsia.rs
index fff9fc6b3bbc8..2b1a3ecfd70f5 100644
--- a/src/libstd/sys/unix/process/process_fuchsia.rs
+++ b/src/libstd/sys/unix/process/process_fuchsia.rs
@@ -1,11 +1,13 @@
+use crate::convert::TryInto;
 use crate::io;
+use crate::fmt;
 use crate::mem;
 use crate::ptr;
 
 use crate::sys::process::zircon::{Handle, zx_handle_t};
 use crate::sys::process::process_common::*;
 
-use libc::size_t;
+use libc::{c_int, size_t};
 
 ////////////////////////////////////////////////////////////////////////////////
 // Command
@@ -160,7 +162,7 @@ impl Process {
             return Err(io::Error::new(io::ErrorKind::InvalidData,
                                       "Failed to get exit status of process"));
         }
-        Ok(ExitStatus::new(proc_info.rec.return_code))
+        Ok(ExitStatus(proc_info.return_code))
     }
 
     pub fn try_wait(&mut self) -> io::Result<Option<ExitStatus>> {
@@ -190,6 +192,36 @@ impl Process {
             return Err(io::Error::new(io::ErrorKind::InvalidData,
                                       "Failed to get exit status of process"));
         }
-        Ok(Some(ExitStatus::new(proc_info.rec.return_code)))
+        Ok(Some(ExitStatus(proc_info.return_code)))
+    }
+}
+
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+pub struct ExitStatus(i64);
+
+impl ExitStatus {
+    pub fn success(&self) -> bool {
+        self.code() == Some(0)
+    }
+
+    pub fn code(&self) -> Option<i32> {
+        // FIXME: support extracting return code as an i64
+        self.0.try_into().ok()
+    }
+
+    pub fn signal(&self) -> Option<i32> {
+        None
+    }
+}
+
+impl From<c_int> for ExitStatus {
+    fn from(a: c_int) -> ExitStatus {
+        ExitStatus(a as i64)
+    }
+}
+
+impl fmt::Display for ExitStatus {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "exit code: {}", self.0)
     }
 }
diff --git a/src/libstd/sys/unix/process/process_unix.rs b/src/libstd/sys/unix/process/process_unix.rs
index e6a742bd45d0b..507dc6892613a 100644
--- a/src/libstd/sys/unix/process/process_unix.rs
+++ b/src/libstd/sys/unix/process/process_unix.rs
@@ -1,3 +1,4 @@
+use crate::fmt;
 use crate::io::{self, Error, ErrorKind};
 use crate::ptr;
 use crate::sys::cvt;
@@ -441,3 +442,54 @@ impl Process {
         }
     }
 }
+
+/// Unix exit statuses
+#[derive(PartialEq, Eq, Clone, Copy, Debug)]
+pub struct ExitStatus(c_int);
+
+impl ExitStatus {
+    pub fn new(status: c_int) -> ExitStatus {
+        ExitStatus(status)
+    }
+
+    fn exited(&self) -> bool {
+        unsafe { libc::WIFEXITED(self.0) }
+    }
+
+    pub fn success(&self) -> bool {
+        self.code() == Some(0)
+    }
+
+    pub fn code(&self) -> Option<i32> {
+        if self.exited() {
+            Some(unsafe { libc::WEXITSTATUS(self.0) })
+        } else {
+            None
+        }
+    }
+
+    pub fn signal(&self) -> Option<i32> {
+        if !self.exited() {
+            Some(unsafe { libc::WTERMSIG(self.0) })
+        } else {
+            None
+        }
+    }
+}
+
+impl From<c_int> for ExitStatus {
+    fn from(a: c_int) -> ExitStatus {
+        ExitStatus(a)
+    }
+}
+
+impl fmt::Display for ExitStatus {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        if let Some(code) = self.code() {
+            write!(f, "exit code: {}", code)
+        } else {
+            let signal = self.signal().unwrap();
+            write!(f, "signal: {}", signal)
+        }
+    }
+}
diff --git a/src/libstd/sys/unix/process/zircon.rs b/src/libstd/sys/unix/process/zircon.rs
index 1ba48de3c0785..188a6b5f2da4a 100644
--- a/src/libstd/sys/unix/process/zircon.rs
+++ b/src/libstd/sys/unix/process/zircon.rs
@@ -65,29 +65,14 @@ impl Drop for Handle {
     }
 }
 
-// Common ZX_INFO header
-#[derive(Default)]
-#[repr(C)]
-pub struct zx_info_header_t {
-    pub topic: u32,              // identifies the info struct
-    pub avail_topic_size: u16,   // “native” size of the struct
-    pub topic_size: u16,         // size of the returned struct (<=topic_size)
-    pub avail_count: u32,        // number of records the kernel has
-    pub count: u32,              // number of records returned (limited by buffer size)
-}
-
-#[derive(Default)]
-#[repr(C)]
-pub struct zx_record_process_t {
-    pub return_code: c_int,
-}
-
 // Returned for topic ZX_INFO_PROCESS
 #[derive(Default)]
 #[repr(C)]
 pub struct zx_info_process_t {
-    pub hdr: zx_info_header_t,
-    pub rec: zx_record_process_t,
+    pub return_code: i64,
+    pub started: bool,
+    pub exited: bool,
+    pub debugger_attached: bool,
 }
 
 extern {
diff --git a/src/libsyntax/feature_gate/builtin_attrs.rs b/src/libsyntax/feature_gate/builtin_attrs.rs
index b6e13200f32af..d14afc6deaa69 100644
--- a/src/libsyntax/feature_gate/builtin_attrs.rs
+++ b/src/libsyntax/feature_gate/builtin_attrs.rs
@@ -457,7 +457,6 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
     // ==========================================================================
     // Internal attributes, Misc:
     // ==========================================================================
-
     gated!(
         lang, Normal, template!(NameValueStr: "name"), lang_items,
         "language items are subject to change",
@@ -498,6 +497,10 @@ pub const BUILTIN_ATTRIBUTES: &[BuiltinAttribute] = &[
         overflow checking behavior of several libcore functions that are inlined \
         across crates and will never be stable",
     ),
+    rustc_attr!(rustc_reservation_impl, Normal, template!(NameValueStr: "reservation message"),
+                "the `#[rustc_reservation_impl]` attribute is internally used \
+                 for reserving for `for<T> From<!> for T` impl"
+    ),
     rustc_attr!(
         rustc_test_marker, Normal, template!(Word),
         "the `#[rustc_test_marker]` attribute is used internally to track tests",
diff --git a/src/libsyntax_pos/symbol.rs b/src/libsyntax_pos/symbol.rs
index 597ae83572cee..32af930ffb884 100644
--- a/src/libsyntax_pos/symbol.rs
+++ b/src/libsyntax_pos/symbol.rs
@@ -606,6 +606,7 @@ symbols! {
         rustc_std_internal_symbol,
         rustc_symbol_name,
         rustc_synthetic,
+        rustc_reservation_impl,
         rustc_test_marker,
         rustc_then_this_would_need,
         rustc_variance,
diff --git a/src/test/ui-fulldeps/internal-lints/ty_tykind_usage.rs b/src/test/ui-fulldeps/internal-lints/ty_tykind_usage.rs
index c6bd122f4e548..f716a78a031f2 100644
--- a/src/test/ui-fulldeps/internal-lints/ty_tykind_usage.rs
+++ b/src/test/ui-fulldeps/internal-lints/ty_tykind_usage.rs
@@ -8,9 +8,9 @@ use rustc::ty::{self, Ty, TyKind};
 
 #[deny(rustc::usage_of_ty_tykind)]
 fn main() {
-    let sty = TyKind::Bool; //~ ERROR usage of `ty::TyKind::<kind>`
+    let kind = TyKind::Bool; //~ ERROR usage of `ty::TyKind::<kind>`
 
-    match sty {
+    match kind {
         TyKind::Bool => (), //~ ERROR usage of `ty::TyKind::<kind>`
         TyKind::Char => (), //~ ERROR usage of `ty::TyKind::<kind>`
         TyKind::Int(..) => (), //~ ERROR usage of `ty::TyKind::<kind>`
@@ -41,9 +41,9 @@ fn main() {
         TyKind::Error => (), //~ ERROR usage of `ty::TyKind::<kind>`
     }
 
-    if let ty::Int(int_ty) = sty {}
+    if let ty::Int(int_ty) = kind {}
 
-    if let TyKind::Int(int_ty) = sty {} //~ ERROR usage of `ty::TyKind::<kind>`
+    if let TyKind::Int(int_ty) = kind {} //~ ERROR usage of `ty::TyKind::<kind>`
 
     fn ty_kind(ty_bad: TyKind<'_>, ty_good: Ty<'_>) {} //~ ERROR usage of `ty::TyKind`
 }
diff --git a/src/test/ui-fulldeps/internal-lints/ty_tykind_usage.stderr b/src/test/ui-fulldeps/internal-lints/ty_tykind_usage.stderr
index 8add4252c4103..28c837adac3a1 100644
--- a/src/test/ui-fulldeps/internal-lints/ty_tykind_usage.stderr
+++ b/src/test/ui-fulldeps/internal-lints/ty_tykind_usage.stderr
@@ -1,8 +1,8 @@
 error: usage of `ty::TyKind::<kind>`
-  --> $DIR/ty_tykind_usage.rs:11:15
+  --> $DIR/ty_tykind_usage.rs:11:16
    |
-LL |     let sty = TyKind::Bool;
-   |               ^^^^^^ help: try using ty::<kind> directly: `ty`
+LL |     let kind = TyKind::Bool;
+   |                ^^^^^^ help: try using ty::<kind> directly: `ty`
    |
 note: lint level defined here
   --> $DIR/ty_tykind_usage.rs:9:8
@@ -181,7 +181,7 @@ LL |         TyKind::Error => (),
 error: usage of `ty::TyKind::<kind>`
   --> $DIR/ty_tykind_usage.rs:46:12
    |
-LL |     if let TyKind::Int(int_ty) = sty {}
+LL |     if let TyKind::Int(int_ty) = kind {}
    |            ^^^^^^ help: try using ty::<kind> directly: `ty`
 
 error: usage of `ty::TyKind`
diff --git a/src/test/ui/borrowck/borrowck-anon-fields-variant.nll.stderr b/src/test/ui/borrowck/borrowck-anon-fields-variant.nll.stderr
deleted file mode 100644
index f66994b3f100a..0000000000000
--- a/src/test/ui/borrowck/borrowck-anon-fields-variant.nll.stderr
+++ /dev/null
@@ -1,40 +0,0 @@
-error[E0503]: cannot use `y` because it was mutably borrowed
-  --> $DIR/borrowck-anon-fields-variant.rs:17:7
-   |
-LL |       Foo::Y(ref mut a, _) => a,
-   |              --------- borrow of `y.0` occurs here
-...
-LL |       Foo::Y(_, ref mut b) => b,
-   |       ^^^^^^^^^^^^^^^^^^^^ use of borrowed `y.0`
-...
-LL |     *a += 1;
-   |     ------- borrow later used here
-
-error[E0503]: cannot use `y` because it was mutably borrowed
-  --> $DIR/borrowck-anon-fields-variant.rs:37:7
-   |
-LL |       Foo::Y(ref mut a, _) => a,
-   |              --------- borrow of `y.0` occurs here
-...
-LL |       Foo::Y(ref mut b, _) => b,
-   |       ^^^^^^^^^^^^^^^^^^^^ use of borrowed `y.0`
-...
-LL |     *a += 1;
-   |     ------- borrow later used here
-
-error[E0499]: cannot borrow `y.0` as mutable more than once at a time
-  --> $DIR/borrowck-anon-fields-variant.rs:37:14
-   |
-LL |       Foo::Y(ref mut a, _) => a,
-   |              --------- first mutable borrow occurs here
-...
-LL |       Foo::Y(ref mut b, _) => b,
-   |              ^^^^^^^^^ second mutable borrow occurs here
-...
-LL |     *a += 1;
-   |     ------- first borrow later used here
-
-error: aborting due to 3 previous errors
-
-Some errors have detailed explanations: E0499, E0503.
-For more information about an error, try `rustc --explain E0499`.
diff --git a/src/test/ui/borrowck/borrowck-anon-fields-variant.rs b/src/test/ui/borrowck/borrowck-anon-fields-variant.rs
index 695809f58c551..cecc278e1931c 100644
--- a/src/test/ui/borrowck/borrowck-anon-fields-variant.rs
+++ b/src/test/ui/borrowck/borrowck-anon-fields-variant.rs
@@ -15,9 +15,7 @@ fn distinct_variant() {
     // reference.
     let b = match y {
       Foo::Y(_, ref mut b) => b,
-      //~^ WARNING cannot use `y`
-      //~| WARNING this error has been downgraded to a warning
-      //~| WARNING this warning will become a hard error in the future
+      //~^ ERROR cannot use `y`
       Foo::X => panic!()
     };
 
diff --git a/src/test/ui/borrowck/borrowck-anon-fields-variant.stderr b/src/test/ui/borrowck/borrowck-anon-fields-variant.stderr
index e2d3e417ac3ac..2caeed1bd44ea 100644
--- a/src/test/ui/borrowck/borrowck-anon-fields-variant.stderr
+++ b/src/test/ui/borrowck/borrowck-anon-fields-variant.stderr
@@ -1,4 +1,4 @@
-warning[E0503]: cannot use `y` because it was mutably borrowed
+error[E0503]: cannot use `y` because it was mutably borrowed
   --> $DIR/borrowck-anon-fields-variant.rs:17:7
    |
 LL |       Foo::Y(ref mut a, _) => a,
@@ -9,13 +9,9 @@ LL |       Foo::Y(_, ref mut b) => b,
 ...
 LL |     *a += 1;
    |     ------- borrow later used here
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
 
 error[E0503]: cannot use `y` because it was mutably borrowed
-  --> $DIR/borrowck-anon-fields-variant.rs:37:7
+  --> $DIR/borrowck-anon-fields-variant.rs:35:7
    |
 LL |       Foo::Y(ref mut a, _) => a,
    |              --------- borrow of `y.0` occurs here
@@ -27,7 +23,7 @@ LL |     *a += 1;
    |     ------- borrow later used here
 
 error[E0499]: cannot borrow `y.0` as mutable more than once at a time
-  --> $DIR/borrowck-anon-fields-variant.rs:37:14
+  --> $DIR/borrowck-anon-fields-variant.rs:35:14
    |
 LL |       Foo::Y(ref mut a, _) => a,
    |              --------- first mutable borrow occurs here
@@ -38,7 +34,7 @@ LL |       Foo::Y(ref mut b, _) => b,
 LL |     *a += 1;
    |     ------- first borrow later used here
 
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 
 Some errors have detailed explanations: E0499, E0503.
 For more information about an error, try `rustc --explain E0499`.
diff --git a/src/test/ui/borrowck/borrowck-describe-lvalue.nll.stderr b/src/test/ui/borrowck/borrowck-describe-lvalue.nll.stderr
deleted file mode 100644
index 20f05353d4633..0000000000000
--- a/src/test/ui/borrowck/borrowck-describe-lvalue.nll.stderr
+++ /dev/null
@@ -1,366 +0,0 @@
-error[E0499]: cannot borrow `x` as mutable more than once at a time
-  --> $DIR/borrowck-describe-lvalue.rs:262:13
-   |
-LL |             let y = &mut x;
-   |                     ------ first mutable borrow occurs here
-LL |             &mut x;
-   |             ^^^^^^ second mutable borrow occurs here
-LL |             *y = 1;
-   |             ------ first borrow later used here
-
-error[E0499]: cannot borrow `x` as mutable more than once at a time
-  --> $DIR/borrowck-describe-lvalue.rs:272:20
-   |
-LL |                    let y = &mut x;
-   |                            ------ first mutable borrow occurs here
-LL |                    &mut x;
-   |                    ^^^^^^ second mutable borrow occurs here
-LL |                    *y = 1;
-   |                    ------ first borrow later used here
-
-error: captured variable cannot escape `FnMut` closure body
-  --> $DIR/borrowck-describe-lvalue.rs:270:16
-   |
-LL |              || {
-   |               - inferred to be a `FnMut` closure
-LL | /                || {
-LL | |                    let y = &mut x;
-LL | |                    &mut x;
-LL | |                    *y = 1;
-LL | |                    drop(y);
-LL | |                 }
-   | |_________________^ returns a closure that contains a reference to a captured variable, which then escapes the closure body
-   |
-   = note: `FnMut` closures only have access to their captured variables while they are executing...
-   = note: ...therefore, they cannot allow references to captured variables to escape
-
-error[E0503]: cannot use `f.x` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:41:9
-   |
-LL |         let x = f.x();
-   |                 - borrow of `f` occurs here
-LL |         f.x;
-   |         ^^^ use of borrowed `f`
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `g.0` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:48:9
-   |
-LL |         let x = g.x();
-   |                 - borrow of `g` occurs here
-LL |         g.0;
-   |         ^^^ use of borrowed `g`
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `h.0` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:55:9
-   |
-LL |         let x = &mut h.0;
-   |                 -------- borrow of `h.0` occurs here
-LL |         h.0;
-   |         ^^^ use of borrowed `h.0`
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `e.0` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:63:20
-   |
-LL |         let x = e.x();
-   |                 - borrow of `e` occurs here
-LL |         match e {
-LL |             Baz::X(value) => value
-   |                    ^^^^^ use of borrowed `e`
-LL |         };
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `u.a` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:71:9
-   |
-LL |         let x = &mut u.a;
-   |                 -------- borrow of `u.a` occurs here
-LL |         u.a;
-   |         ^^^ use of borrowed `u.a`
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `f.x` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:78:9
-   |
-LL |         let x = f.x();
-   |                 - borrow of `*f` occurs here
-LL |         f.x;
-   |         ^^^ use of borrowed `*f`
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `g.0` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:85:9
-   |
-LL |         let x = g.x();
-   |                 - borrow of `*g` occurs here
-LL |         g.0;
-   |         ^^^ use of borrowed `*g`
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `h.0` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:92:9
-   |
-LL |         let x = &mut h.0;
-   |                 -------- borrow of `h.0` occurs here
-LL |         h.0;
-   |         ^^^ use of borrowed `h.0`
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `e.0` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:100:20
-   |
-LL |         let x = e.x();
-   |                 - borrow of `*e` occurs here
-LL |         match *e {
-LL |             Baz::X(value) => value
-   |                    ^^^^^ use of borrowed `*e`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `u.a` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:109:9
-   |
-LL |         let x = &mut u.a;
-   |                 -------- borrow of `u.a` occurs here
-LL |         u.a;
-   |         ^^^ use of borrowed `u.a`
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `v[..]` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:117:15
-   |
-LL |         let x = &mut v;
-   |                 ------ borrow of `v` occurs here
-LL |         match v {
-LL |             &[x, _, .., _, _] => println!("{}", x),
-   |               ^ use of borrowed `v`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `v[..]` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:122:18
-   |
-LL |         let x = &mut v;
-   |                 ------ borrow of `v` occurs here
-...
-LL |             &[_, x, .., _, _] => println!("{}", x),
-   |                  ^ use of borrowed `v`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `v[..]` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:127:25
-   |
-LL |         let x = &mut v;
-   |                 ------ borrow of `v` occurs here
-...
-LL |             &[_, _, .., x, _] => println!("{}", x),
-   |                         ^ use of borrowed `v`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `v[..]` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:132:28
-   |
-LL |         let x = &mut v;
-   |                 ------ borrow of `v` occurs here
-...
-LL |             &[_, _, .., _, x] => println!("{}", x),
-   |                            ^ use of borrowed `v`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `v[..]` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:143:15
-   |
-LL |         let x = &mut v;
-   |                 ------ borrow of `v` occurs here
-LL |         match v {
-LL |             &[x @ ..] => println!("{:?}", x),
-   |               ^^^^^^ use of borrowed `v`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `v[..]` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:148:18
-   |
-LL |         let x = &mut v;
-   |                 ------ borrow of `v` occurs here
-...
-LL |             &[_, x @ ..] => println!("{:?}", x),
-   |                  ^^^^^^ use of borrowed `v`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `v[..]` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:153:15
-   |
-LL |         let x = &mut v;
-   |                 ------ borrow of `v` occurs here
-...
-LL |             &[x @ .., _] => println!("{:?}", x),
-   |               ^^^^^^ use of borrowed `v`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `v[..]` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:158:18
-   |
-LL |         let x = &mut v;
-   |                 ------ borrow of `v` occurs here
-...
-LL |             &[_, x @ .., _] => println!("{:?}", x),
-   |                  ^^^^^^ use of borrowed `v`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `e` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:171:13
-   |
-LL |         let x = &mut e;
-   |                 ------ borrow of `e` occurs here
-LL |         match e {
-LL |             E::A(ref ax) =>
-   |             ^^^^^^^^^^^^ use of borrowed `e`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0502]: cannot borrow `e.0` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-describe-lvalue.rs:171:18
-   |
-LL |         let x = &mut e;
-   |                 ------ mutable borrow occurs here
-LL |         match e {
-LL |             E::A(ref ax) =>
-   |                  ^^^^^^ immutable borrow occurs here
-...
-LL |         drop(x);
-   |              - mutable borrow later used here
-
-error[E0502]: cannot borrow `e.x` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-describe-lvalue.rs:175:23
-   |
-LL |         let x = &mut e;
-   |                 ------ mutable borrow occurs here
-...
-LL |             E::B { x: ref bx } =>
-   |                       ^^^^^^ immutable borrow occurs here
-...
-LL |         drop(x);
-   |              - mutable borrow later used here
-
-error[E0502]: cannot borrow `s.y.0` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-describe-lvalue.rs:188:22
-   |
-LL |         let x = &mut s;
-   |                 ------ mutable borrow occurs here
-LL |         match s {
-LL |             S  { y: (ref y0, _), .. } =>
-   |                      ^^^^^^ immutable borrow occurs here
-...
-LL |         drop(x);
-   |              - mutable borrow later used here
-
-error[E0502]: cannot borrow `s.x.y` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-describe-lvalue.rs:194:28
-   |
-LL |         let x = &mut s;
-   |                 ------ mutable borrow occurs here
-...
-LL |             S  { x: F { y: ref x0, .. }, .. } =>
-   |                            ^^^^^^ immutable borrow occurs here
-...
-LL |         drop(x);
-   |              - mutable borrow later used here
-
-error[E0503]: cannot use `*v` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:240:9
-   |
-LL |         let x = &mut v;
-   |                 ------ borrow of `v` occurs here
-LL |         v[0].y;
-   |         ^^^^ use of borrowed `v`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0503]: cannot use `v[_].y` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:240:9
-   |
-LL |         let x = &mut v;
-   |                 ------ borrow of `v` occurs here
-LL |         v[0].y;
-   |         ^^^^^^ use of borrowed `v`
-...
-LL |         drop(x);
-   |              - borrow later used here
-
-error[E0502]: cannot borrow `v[..].x` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-describe-lvalue.rs:251:24
-   |
-LL |         let x = &mut v;
-   |                 ------ mutable borrow occurs here
-LL |         match v {
-LL |             &[_, F {x: ref xf, ..}] => println!("{}", xf),
-   |                        ^^^^^^ immutable borrow occurs here
-...
-LL |         drop(x);
-   |              - mutable borrow later used here
-
-error[E0502]: cannot borrow `*block.current` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-describe-lvalue.rs:210:29
-   |
-LL |             let x = &mut block;
-   |                     ---------- mutable borrow occurs here
-LL |             let p: &'a u8 = &*block.current;
-   |                             ^^^^^^^^^^^^^^^ immutable borrow occurs here
-...
-LL |             drop(x);
-   |                  - mutable borrow later used here
-
-error[E0502]: cannot borrow `*block.current` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-describe-lvalue.rs:227:33
-   |
-LL |             let x = &mut block;
-   |                     ---------- mutable borrow occurs here
-LL |             let p : *const u8 = &*(*block).current;
-   |                                 ^^^^^^^^^^^^^^^^^^ immutable borrow occurs here
-...
-LL |             drop(x);
-   |                  - mutable borrow later used here
-
-error[E0382]: use of moved value: `x`
-  --> $DIR/borrowck-describe-lvalue.rs:282:22
-   |
-LL |                 drop(x);
-   |                      - value moved here
-LL |                 drop(x);
-   |                      ^ value used here after move
-   |
-   = note: move occurs because `x` has type `std::vec::Vec<i32>`, which does not implement the `Copy` trait
-
-error: aborting due to 32 previous errors
-
-Some errors have detailed explanations: E0382, E0499, E0502, E0503.
-For more information about an error, try `rustc --explain E0382`.
diff --git a/src/test/ui/borrowck/borrowck-describe-lvalue.rs b/src/test/ui/borrowck/borrowck-describe-lvalue.rs
index c27d9519dc798..8425960aa8600 100644
--- a/src/test/ui/borrowck/borrowck-describe-lvalue.rs
+++ b/src/test/ui/borrowck/borrowck-describe-lvalue.rs
@@ -208,10 +208,8 @@ fn main() {
         fn bump<'a>(mut block: &mut Block<'a>) {
             let x = &mut block;
             let p: &'a u8 = &*block.current;
-            //~^ WARNING cannot borrow `*block.current` as immutable because it is also borrowed as mutable
-            //~| this error has been downgraded
-            //~| this warning will become a hard error in the future
-            // Warning because of issue rust#38899
+            //~^ ERROR cannot borrow `*block.current` as immutable because it is also borrowed as mutable
+            // See issue rust#38899
             drop(x);
         }
     }
@@ -225,10 +223,8 @@ fn main() {
         unsafe fn bump2(mut block: *mut Block2) {
             let x = &mut block;
             let p : *const u8 = &*(*block).current;
-            //~^ WARNING cannot borrow `*block.current` as immutable because it is also borrowed as mutable
-            //~| this error has been downgraded
-            //~| this warning will become a hard error in the future
-            // Warning because of issue rust#38899
+            //~^ ERROR cannot borrow `*block.current` as immutable because it is also borrowed as mutable
+            // See issue rust#38899
             drop(x);
         }
     }
diff --git a/src/test/ui/borrowck/borrowck-describe-lvalue.stderr b/src/test/ui/borrowck/borrowck-describe-lvalue.stderr
index 38d847a90ff95..4213523d2fa4b 100644
--- a/src/test/ui/borrowck/borrowck-describe-lvalue.stderr
+++ b/src/test/ui/borrowck/borrowck-describe-lvalue.stderr
@@ -1,5 +1,5 @@
 error[E0499]: cannot borrow `x` as mutable more than once at a time
-  --> $DIR/borrowck-describe-lvalue.rs:262:13
+  --> $DIR/borrowck-describe-lvalue.rs:258:13
    |
 LL |             let y = &mut x;
    |                     ------ first mutable borrow occurs here
@@ -9,7 +9,7 @@ LL |             *y = 1;
    |             ------ first borrow later used here
 
 error[E0499]: cannot borrow `x` as mutable more than once at a time
-  --> $DIR/borrowck-describe-lvalue.rs:272:20
+  --> $DIR/borrowck-describe-lvalue.rs:268:20
    |
 LL |                    let y = &mut x;
    |                            ------ first mutable borrow occurs here
@@ -19,7 +19,7 @@ LL |                    *y = 1;
    |                    ------ first borrow later used here
 
 error: captured variable cannot escape `FnMut` closure body
-  --> $DIR/borrowck-describe-lvalue.rs:270:16
+  --> $DIR/borrowck-describe-lvalue.rs:266:16
    |
 LL |              || {
    |               - inferred to be a `FnMut` closure
@@ -295,7 +295,7 @@ LL |         drop(x);
    |              - mutable borrow later used here
 
 error[E0503]: cannot use `*v` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:240:9
+  --> $DIR/borrowck-describe-lvalue.rs:236:9
    |
 LL |         let x = &mut v;
    |                 ------ borrow of `v` occurs here
@@ -306,7 +306,7 @@ LL |         drop(x);
    |              - borrow later used here
 
 error[E0503]: cannot use `v[_].y` because it was mutably borrowed
-  --> $DIR/borrowck-describe-lvalue.rs:240:9
+  --> $DIR/borrowck-describe-lvalue.rs:236:9
    |
 LL |         let x = &mut v;
    |                 ------ borrow of `v` occurs here
@@ -317,7 +317,7 @@ LL |         drop(x);
    |              - borrow later used here
 
 error[E0502]: cannot borrow `v[..].x` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-describe-lvalue.rs:251:24
+  --> $DIR/borrowck-describe-lvalue.rs:247:24
    |
 LL |         let x = &mut v;
    |                 ------ mutable borrow occurs here
@@ -328,7 +328,7 @@ LL |             &[_, F {x: ref xf, ..}] => println!("{}", xf),
 LL |         drop(x);
    |              - mutable borrow later used here
 
-warning[E0502]: cannot borrow `*block.current` as immutable because it is also borrowed as mutable
+error[E0502]: cannot borrow `*block.current` as immutable because it is also borrowed as mutable
   --> $DIR/borrowck-describe-lvalue.rs:210:29
    |
 LL |             let x = &mut block;
@@ -338,13 +338,9 @@ LL |             let p: &'a u8 = &*block.current;
 ...
 LL |             drop(x);
    |                  - mutable borrow later used here
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
 
-warning[E0502]: cannot borrow `*block.current` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-describe-lvalue.rs:227:33
+error[E0502]: cannot borrow `*block.current` as immutable because it is also borrowed as mutable
+  --> $DIR/borrowck-describe-lvalue.rs:225:33
    |
 LL |             let x = &mut block;
    |                     ---------- mutable borrow occurs here
@@ -353,13 +349,9 @@ LL |             let p : *const u8 = &*(*block).current;
 ...
 LL |             drop(x);
    |                  - mutable borrow later used here
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
 
 error[E0382]: use of moved value: `x`
-  --> $DIR/borrowck-describe-lvalue.rs:282:22
+  --> $DIR/borrowck-describe-lvalue.rs:278:22
    |
 LL |                 drop(x);
    |                      - value moved here
@@ -368,7 +360,7 @@ LL |                 drop(x);
    |
    = note: move occurs because `x` has type `std::vec::Vec<i32>`, which does not implement the `Copy` trait
 
-error: aborting due to 30 previous errors
+error: aborting due to 32 previous errors
 
 Some errors have detailed explanations: E0382, E0499, E0502, E0503.
 For more information about an error, try `rustc --explain E0382`.
diff --git a/src/test/ui/borrowck/borrowck-migrate-to-nll.edition.stderr b/src/test/ui/borrowck/borrowck-migrate-to-nll.edition.stderr
deleted file mode 100644
index 58f2cadcc6573..0000000000000
--- a/src/test/ui/borrowck/borrowck-migrate-to-nll.edition.stderr
+++ /dev/null
@@ -1,14 +0,0 @@
-error[E0502]: cannot borrow `*block.current` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-migrate-to-nll.rs:29:21
-   |
-LL |     let x = &mut block;
-   |             ---------- mutable borrow occurs here
-LL |     let p: &'a u8 = &*block.current;
-   |                     ^^^^^^^^^^^^^^^ immutable borrow occurs here
-...
-LL |     drop(x);
-   |          - mutable borrow later used here
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0502`.
diff --git a/src/test/ui/borrowck/borrowck-migrate-to-nll.rs b/src/test/ui/borrowck/borrowck-migrate-to-nll.rs
deleted file mode 100644
index 6587dfdbc03f3..0000000000000
--- a/src/test/ui/borrowck/borrowck-migrate-to-nll.rs
+++ /dev/null
@@ -1,36 +0,0 @@
-// This is a test of the borrowck migrate mode. It leverages #38899, a
-// bug that is fixed by NLL: this code is (unsoundly) accepted by
-// AST-borrowck, but is correctly rejected by the NLL borrowck.
-//
-// Therefore, for backwards-compatiblity, under borrowck=migrate the
-// NLL checks will be emitted as *warnings*.
-//
-// In Rust 2018, no errors will be downgraded to warnings.
-
-// NLL mode makes this compile-fail; we cannot currently encode a
-// test that is run-pass or compile-fail based on compare-mode. So
-// just ignore it instead:
-
-// ignore-compare-mode-nll
-// ignore-compare-mode-polonius
-
-// revisions: zflag edition
-//[zflag]compile-flags: -Z borrowck=migrate
-//[edition]edition:2018
-//[zflag] check-pass
-
-pub struct Block<'a> {
-    current: &'a u8,
-    unrelated: &'a u8,
-}
-
-fn bump<'a>(mut block: &mut Block<'a>) {
-    let x = &mut block;
-    let p: &'a u8 = &*block.current;
-    //[edition]~^ ERROR cannot borrow `*block.current` as immutable
-    // (use `x` and `p` so enabling NLL doesn't assign overly short lifetimes)
-    drop(x);
-    drop(p);
-}
-
-fn main() {}
diff --git a/src/test/ui/borrowck/borrowck-migrate-to-nll.zflag.stderr b/src/test/ui/borrowck/borrowck-migrate-to-nll.zflag.stderr
deleted file mode 100644
index ace336a3bf32a..0000000000000
--- a/src/test/ui/borrowck/borrowck-migrate-to-nll.zflag.stderr
+++ /dev/null
@@ -1,15 +0,0 @@
-warning[E0502]: cannot borrow `*block.current` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowck-migrate-to-nll.rs:29:21
-   |
-LL |     let x = &mut block;
-   |             ---------- mutable borrow occurs here
-LL |     let p: &'a u8 = &*block.current;
-   |                     ^^^^^^^^^^^^^^^ immutable borrow occurs here
-...
-LL |     drop(x);
-   |          - mutable borrow later used here
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
-
diff --git a/src/test/ui/borrowck/issue-53432-nested-closure-outlives-borrowed-value.rs b/src/test/ui/borrowck/issue-53432-nested-closure-outlives-borrowed-value.rs
new file mode 100644
index 0000000000000..f1fd1b507c71e
--- /dev/null
+++ b/src/test/ui/borrowck/issue-53432-nested-closure-outlives-borrowed-value.rs
@@ -0,0 +1,7 @@
+fn main() {
+    let f = move || {};
+    let _action = move || {
+        || f() // The `nested` closure
+        //~^ ERROR lifetime may not live long enough
+    };
+}
diff --git a/src/test/ui/borrowck/issue-53432-nested-closure-outlives-borrowed-value.stderr b/src/test/ui/borrowck/issue-53432-nested-closure-outlives-borrowed-value.stderr
new file mode 100644
index 0000000000000..3781691ff41dc
--- /dev/null
+++ b/src/test/ui/borrowck/issue-53432-nested-closure-outlives-borrowed-value.stderr
@@ -0,0 +1,15 @@
+error: lifetime may not live long enough
+  --> $DIR/issue-53432-nested-closure-outlives-borrowed-value.rs:4:9
+   |
+LL |     let _action = move || {
+   |                   -------
+   |                   |     |
+   |                   |     return type of closure is [closure@$DIR/issue-53432-nested-closure-outlives-borrowed-value.rs:4:9: 4:15 f:&'2 [closure@$DIR/issue-53432-nested-closure-outlives-borrowed-value.rs:2:13: 2:23]]
+   |                   lifetime `'1` represents this closure's body
+LL |         || f() // The `nested` closure
+   |         ^^^^^^ returning this value requires that `'1` must outlive `'2`
+   |
+   = note: closure implements `Fn`, so references to captured variables can't escape the closure
+
+error: aborting due to previous error
+
diff --git a/src/test/ui/consts/min_const_fn/min_const_fn.nll.stderr b/src/test/ui/consts/min_const_fn/min_const_fn.nll.stderr
deleted file mode 100644
index 4b43a0d0a1a1b..0000000000000
--- a/src/test/ui/consts/min_const_fn/min_const_fn.nll.stderr
+++ /dev/null
@@ -1,328 +0,0 @@
-error[E0493]: destructors cannot be evaluated at compile-time
-  --> $DIR/min_const_fn.rs:37:25
-   |
-LL |     const fn into_inner(self) -> T { self.0 }
-   |                         ^^^^ constant functions cannot evaluate destructors
-
-error[E0723]: mutable references in const fn are unstable
-  --> $DIR/min_const_fn.rs:39:36
-   |
-LL |     const fn get_mut(&mut self) -> &mut T { &mut self.0 }
-   |                                    ^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0493]: destructors cannot be evaluated at compile-time
-  --> $DIR/min_const_fn.rs:44:28
-   |
-LL |     const fn into_inner_lt(self) -> T { self.0 }
-   |                            ^^^^ constant functions cannot evaluate destructors
-
-error[E0723]: mutable references in const fn are unstable
-  --> $DIR/min_const_fn.rs:46:42
-   |
-LL |     const fn get_mut_lt(&'a mut self) -> &mut T { &mut self.0 }
-   |                                          ^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0493]: destructors cannot be evaluated at compile-time
-  --> $DIR/min_const_fn.rs:51:27
-   |
-LL |     const fn into_inner_s(self) -> T { self.0 }
-   |                           ^^^^ constant functions cannot evaluate destructors
-
-error[E0723]: mutable references in const fn are unstable
-  --> $DIR/min_const_fn.rs:53:38
-   |
-LL |     const fn get_mut_s(&mut self) -> &mut T { &mut self.0 }
-   |                                      ^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: mutable references in const fn are unstable
-  --> $DIR/min_const_fn.rs:58:39
-   |
-LL |     const fn get_mut_sq(&mut self) -> &mut T { &mut self.0 }
-   |                                       ^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:76:16
-   |
-LL | const fn foo11<T: std::fmt::Display>(t: T) -> T { t }
-   |                ^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:78:18
-   |
-LL | const fn foo11_2<T: Send>(t: T) -> T { t }
-   |                  ^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: only int, `bool` and `char` operations are stable in const fn
-  --> $DIR/min_const_fn.rs:80:33
-   |
-LL | const fn foo19(f: f32) -> f32 { f * 2.0 }
-   |                                 ^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: only int, `bool` and `char` operations are stable in const fn
-  --> $DIR/min_const_fn.rs:82:35
-   |
-LL | const fn foo19_2(f: f32) -> f32 { 2.0 - f }
-   |                                   ^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: only int and `bool` operations are stable in const fn
-  --> $DIR/min_const_fn.rs:84:35
-   |
-LL | const fn foo19_3(f: f32) -> f32 { -f }
-   |                                   ^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: only int, `bool` and `char` operations are stable in const fn
-  --> $DIR/min_const_fn.rs:86:43
-   |
-LL | const fn foo19_4(f: f32, g: f32) -> f32 { f / g }
-   |                                           ^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: cannot access `static` items in const fn
-  --> $DIR/min_const_fn.rs:90:27
-   |
-LL | const fn foo25() -> u32 { BAR }
-   |                           ^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: cannot access `static` items in const fn
-  --> $DIR/min_const_fn.rs:91:36
-   |
-LL | const fn foo26() -> &'static u32 { &BAR }
-   |                                    ^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: casting pointers to ints is unstable in const fn
-  --> $DIR/min_const_fn.rs:92:42
-   |
-LL | const fn foo30(x: *const u32) -> usize { x as usize }
-   |                                          ^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: casting pointers to ints is unstable in const fn
-  --> $DIR/min_const_fn.rs:94:63
-   |
-LL | const fn foo30_with_unsafe(x: *const u32) -> usize { unsafe { x as usize } }
-   |                                                               ^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: casting pointers to ints is unstable in const fn
-  --> $DIR/min_const_fn.rs:96:42
-   |
-LL | const fn foo30_2(x: *mut u32) -> usize { x as usize }
-   |                                          ^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: casting pointers to ints is unstable in const fn
-  --> $DIR/min_const_fn.rs:98:63
-   |
-LL | const fn foo30_2_with_unsafe(x: *mut u32) -> usize { unsafe { x as usize } }
-   |                                                               ^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: loops and conditional expressions are not stable in const fn
-  --> $DIR/min_const_fn.rs:100:38
-   |
-LL | const fn foo30_4(b: bool) -> usize { if b { 1 } else { 42 } }
-   |                                      ^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: loops are not allowed in const fn
-  --> $DIR/min_const_fn.rs:102:29
-   |
-LL | const fn foo30_5(b: bool) { while b { } }
-   |                             ^^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: loops and conditional expressions are not stable in const fn
-  --> $DIR/min_const_fn.rs:105:44
-   |
-LL | const fn foo36(a: bool, b: bool) -> bool { a && b }
-   |                                            ^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: loops and conditional expressions are not stable in const fn
-  --> $DIR/min_const_fn.rs:107:44
-   |
-LL | const fn foo37(a: bool, b: bool) -> bool { a || b }
-   |                                            ^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: mutable references in const fn are unstable
-  --> $DIR/min_const_fn.rs:109:14
-   |
-LL | const fn inc(x: &mut i32) { *x += 1 }
-   |              ^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:114:6
-   |
-LL | impl<T: std::fmt::Debug> Foo<T> {
-   |      ^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:119:6
-   |
-LL | impl<T: std::fmt::Debug + Sized> Foo<T> {
-   |      ^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:124:6
-   |
-LL | impl<T: Sync + Sized> Foo<T> {
-   |      ^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: `impl Trait` in const fn is unstable
-  --> $DIR/min_const_fn.rs:130:24
-   |
-LL | const fn no_rpit2() -> AlanTuring<impl std::fmt::Debug> { AlanTuring(0) }
-   |                        ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:132:34
-   |
-LL | const fn no_apit2(_x: AlanTuring<impl std::fmt::Debug>) {}
-   |                                  ^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:134:22
-   |
-LL | const fn no_apit(_x: impl std::fmt::Debug) {}
-   |                      ^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: `impl Trait` in const fn is unstable
-  --> $DIR/min_const_fn.rs:135:23
-   |
-LL | const fn no_rpit() -> impl std::fmt::Debug {}
-   |                       ^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:136:23
-   |
-LL | const fn no_dyn_trait(_x: &dyn std::fmt::Debug) {}
-   |                       ^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:137:32
-   |
-LL | const fn no_dyn_trait_ret() -> &'static dyn std::fmt::Debug { &() }
-   |                                ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0515]: cannot return reference to temporary value
-  --> $DIR/min_const_fn.rs:137:63
-   |
-LL | const fn no_dyn_trait_ret() -> &'static dyn std::fmt::Debug { &() }
-   |                                                               ^--
-   |                                                               ||
-   |                                                               |temporary value created here
-   |                                                               returns a reference to data owned by the current function
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:145:41
-   |
-LL | const fn really_no_traits_i_mean_it() { (&() as &dyn std::fmt::Debug, ()).1 }
-   |                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: function pointers in const fn are unstable
-  --> $DIR/min_const_fn.rs:148:21
-   |
-LL | const fn no_fn_ptrs(_x: fn()) {}
-   |                     ^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: function pointers in const fn are unstable
-  --> $DIR/min_const_fn.rs:150:27
-   |
-LL | const fn no_fn_ptrs2() -> fn() { fn foo() {} foo }
-   |                           ^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error: aborting due to 37 previous errors
-
-Some errors have detailed explanations: E0515, E0723.
-For more information about an error, try `rustc --explain E0515`.
diff --git a/src/test/ui/consts/min_const_fn/min_const_fn.rs b/src/test/ui/consts/min_const_fn/min_const_fn.rs
index 8b423da788292..d0f63b148ff2b 100644
--- a/src/test/ui/consts/min_const_fn/min_const_fn.rs
+++ b/src/test/ui/consts/min_const_fn/min_const_fn.rs
@@ -136,9 +136,7 @@ const fn no_rpit() -> impl std::fmt::Debug {} //~ ERROR `impl Trait` in const fn
 const fn no_dyn_trait(_x: &dyn std::fmt::Debug) {} //~ ERROR trait bounds other than `Sized`
 const fn no_dyn_trait_ret() -> &'static dyn std::fmt::Debug { &() }
 //~^ ERROR trait bounds other than `Sized`
-//~| WARNING cannot return reference to temporary value
-//~| WARNING this error has been downgraded to a warning
-//~| WARNING this warning will become a hard error in the future
+//~| ERROR cannot return reference to temporary value
 
 const fn no_unsafe() { unsafe {} }
 
diff --git a/src/test/ui/consts/min_const_fn/min_const_fn.stderr b/src/test/ui/consts/min_const_fn/min_const_fn.stderr
index 211902b687b1b..7919cfe987cfc 100644
--- a/src/test/ui/consts/min_const_fn/min_const_fn.stderr
+++ b/src/test/ui/consts/min_const_fn/min_const_fn.stderr
@@ -286,7 +286,7 @@ LL | const fn no_dyn_trait_ret() -> &'static dyn std::fmt::Debug { &() }
    = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
    = help: add `#![feature(const_fn)]` to the crate attributes to enable
 
-warning[E0515]: cannot return reference to temporary value
+error[E0515]: cannot return reference to temporary value
   --> $DIR/min_const_fn.rs:137:63
    |
 LL | const fn no_dyn_trait_ret() -> &'static dyn std::fmt::Debug { &() }
@@ -294,13 +294,9 @@ LL | const fn no_dyn_trait_ret() -> &'static dyn std::fmt::Debug { &() }
    |                                                               ||
    |                                                               |temporary value created here
    |                                                               returns a reference to data owned by the current function
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
 
 error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn.rs:145:41
+  --> $DIR/min_const_fn.rs:143:41
    |
 LL | const fn really_no_traits_i_mean_it() { (&() as &dyn std::fmt::Debug, ()).1 }
    |                                         ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
@@ -309,7 +305,7 @@ LL | const fn really_no_traits_i_mean_it() { (&() as &dyn std::fmt::Debug, ()).1
    = help: add `#![feature(const_fn)]` to the crate attributes to enable
 
 error[E0723]: function pointers in const fn are unstable
-  --> $DIR/min_const_fn.rs:148:21
+  --> $DIR/min_const_fn.rs:146:21
    |
 LL | const fn no_fn_ptrs(_x: fn()) {}
    |                     ^^
@@ -318,7 +314,7 @@ LL | const fn no_fn_ptrs(_x: fn()) {}
    = help: add `#![feature(const_fn)]` to the crate attributes to enable
 
 error[E0723]: function pointers in const fn are unstable
-  --> $DIR/min_const_fn.rs:150:27
+  --> $DIR/min_const_fn.rs:148:27
    |
 LL | const fn no_fn_ptrs2() -> fn() { fn foo() {} foo }
    |                           ^^^^
@@ -326,7 +322,7 @@ LL | const fn no_fn_ptrs2() -> fn() { fn foo() {} foo }
    = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
    = help: add `#![feature(const_fn)]` to the crate attributes to enable
 
-error: aborting due to 36 previous errors
+error: aborting due to 37 previous errors
 
 Some errors have detailed explanations: E0515, E0723.
 For more information about an error, try `rustc --explain E0515`.
diff --git a/src/test/ui/consts/min_const_fn/min_const_fn_dyn.nll.stderr b/src/test/ui/consts/min_const_fn/min_const_fn_dyn.nll.stderr
deleted file mode 100644
index 0ea950d678f87..0000000000000
--- a/src/test/ui/consts/min_const_fn/min_const_fn_dyn.nll.stderr
+++ /dev/null
@@ -1,31 +0,0 @@
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn_dyn.rs:9:5
-   |
-LL |     x.0.field;
-   |     ^^^^^^^^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0723]: trait bounds other than `Sized` on const fn parameters are unstable
-  --> $DIR/min_const_fn_dyn.rs:12:66
-   |
-LL | const fn no_inner_dyn_trait_ret() -> Hide { Hide(HasDyn { field: &0 }) }
-   |                                                                  ^^
-   |
-   = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
-   = help: add `#![feature(const_fn)]` to the crate attributes to enable
-
-error[E0716]: temporary value dropped while borrowed
-  --> $DIR/min_const_fn_dyn.rs:12:67
-   |
-LL | const fn no_inner_dyn_trait_ret() -> Hide { Hide(HasDyn { field: &0 }) }
-   |                                                                  -^    - temporary value is freed at the end of this statement
-   |                                                                  ||
-   |                                                                  |creates a temporary which is freed while still in use
-   |                                                                  cast requires that borrow lasts for `'static`
-
-error: aborting due to 3 previous errors
-
-Some errors have detailed explanations: E0716, E0723.
-For more information about an error, try `rustc --explain E0716`.
diff --git a/src/test/ui/consts/min_const_fn/min_const_fn_dyn.rs b/src/test/ui/consts/min_const_fn/min_const_fn_dyn.rs
index 75b67192f0081..3833510c0b3b5 100644
--- a/src/test/ui/consts/min_const_fn/min_const_fn_dyn.rs
+++ b/src/test/ui/consts/min_const_fn/min_const_fn_dyn.rs
@@ -11,8 +11,6 @@ const fn no_inner_dyn_trait2(x: Hide) {
 }
 const fn no_inner_dyn_trait_ret() -> Hide { Hide(HasDyn { field: &0 }) }
 //~^ ERROR trait bounds other than `Sized`
-//~| WARNING temporary value dropped while borrowed
-//~| WARNING this error has been downgraded to a warning
-//~| WARNING this warning will become a hard error in the future
+//~| ERROR temporary value dropped while borrowed
 
 fn main() {}
diff --git a/src/test/ui/consts/min_const_fn/min_const_fn_dyn.stderr b/src/test/ui/consts/min_const_fn/min_const_fn_dyn.stderr
index 02ddb0395296c..0ea950d678f87 100644
--- a/src/test/ui/consts/min_const_fn/min_const_fn_dyn.stderr
+++ b/src/test/ui/consts/min_const_fn/min_const_fn_dyn.stderr
@@ -16,7 +16,7 @@ LL | const fn no_inner_dyn_trait_ret() -> Hide { Hide(HasDyn { field: &0 }) }
    = note: for more information, see issue https://github.com/rust-lang/rust/issues/57563
    = help: add `#![feature(const_fn)]` to the crate attributes to enable
 
-warning[E0716]: temporary value dropped while borrowed
+error[E0716]: temporary value dropped while borrowed
   --> $DIR/min_const_fn_dyn.rs:12:67
    |
 LL | const fn no_inner_dyn_trait_ret() -> Hide { Hide(HasDyn { field: &0 }) }
@@ -24,12 +24,8 @@ LL | const fn no_inner_dyn_trait_ret() -> Hide { Hide(HasDyn { field: &0 }) }
    |                                                                  ||
    |                                                                  |creates a temporary which is freed while still in use
    |                                                                  cast requires that borrow lasts for `'static`
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
 
-error: aborting due to 2 previous errors
+error: aborting due to 3 previous errors
 
 Some errors have detailed explanations: E0716, E0723.
 For more information about an error, try `rustc --explain E0716`.
diff --git a/src/test/ui/feature-gates/feature-gate-nll.rs b/src/test/ui/feature-gates/feature-gate-nll.rs
index 8ec752409ab00..fd6c5b67ef69e 100644
--- a/src/test/ui/feature-gates/feature-gate-nll.rs
+++ b/src/test/ui/feature-gates/feature-gate-nll.rs
@@ -1,20 +1,18 @@
 // There isn't a great way to test feature(nll), since it just disables migrate
-// mode and changes some error messages. We just test for migrate mode.
+// mode and changes some error messages.
+
+// FIXME(Centril): This test is probably obsolete now and `nll` should become
+// `accepted`.
 
 // Don't use compare-mode=nll, since that turns on NLL.
 // ignore-compare-mode-nll
 // ignore-compare-mode-polonius
 
-#![feature(rustc_attrs)]
-
-#[rustc_error]
-fn main() { //~ ERROR compilation successful
+fn main() {
     let mut x = (33, &0);
 
     let m = &mut x;
     let p = &*x.1;
-    //~^ WARNING cannot borrow
-    //~| WARNING this error has been downgraded to a warning
-    //~| WARNING this warning will become a hard error in the future
+    //~^ ERROR cannot borrow
     m;
 }
diff --git a/src/test/ui/feature-gates/feature-gate-nll.stderr b/src/test/ui/feature-gates/feature-gate-nll.stderr
index e5b28bbfa2477..edfc22c32c936 100644
--- a/src/test/ui/feature-gates/feature-gate-nll.stderr
+++ b/src/test/ui/feature-gates/feature-gate-nll.stderr
@@ -1,29 +1,13 @@
-warning[E0502]: cannot borrow `*x.1` as immutable because it is also borrowed as mutable
+error[E0502]: cannot borrow `*x.1` as immutable because it is also borrowed as mutable
   --> $DIR/feature-gate-nll.rs:15:13
    |
 LL |     let m = &mut x;
    |             ------ mutable borrow occurs here
 LL |     let p = &*x.1;
    |             ^^^^^ immutable borrow occurs here
-...
+LL |
 LL |     m;
    |     - mutable borrow later used here
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
-
-error: compilation successful
-  --> $DIR/feature-gate-nll.rs:11:1
-   |
-LL | / fn main() {
-LL | |     let mut x = (33, &0);
-LL | |
-LL | |     let m = &mut x;
-...  |
-LL | |     m;
-LL | | }
-   | |_^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-27282-move-match-input-into-guard.rs b/src/test/ui/issues/issue-27282-move-match-input-into-guard.rs
index 0721b051bcbd8..71f1f15654b55 100644
--- a/src/test/ui/issues/issue-27282-move-match-input-into-guard.rs
+++ b/src/test/ui/issues/issue-27282-move-match-input-into-guard.rs
@@ -7,8 +7,6 @@
 // reaches the panic code when executed, despite the compiler warning
 // about that match arm being unreachable.
 
-#![feature(nll)]
-
 fn main() {
     let b = &mut true;
     match b {
diff --git a/src/test/ui/issues/issue-27282-move-match-input-into-guard.stderr b/src/test/ui/issues/issue-27282-move-match-input-into-guard.stderr
index 6993419326c8e..51f9b464d7660 100644
--- a/src/test/ui/issues/issue-27282-move-match-input-into-guard.stderr
+++ b/src/test/ui/issues/issue-27282-move-match-input-into-guard.stderr
@@ -1,5 +1,5 @@
 error[E0382]: use of moved value: `b`
-  --> $DIR/issue-27282-move-match-input-into-guard.rs:18:14
+  --> $DIR/issue-27282-move-match-input-into-guard.rs:16:14
    |
 LL |     let b = &mut true;
    |         - move occurs because `b` has type `&mut bool`, which does not implement the `Copy` trait
diff --git a/src/test/ui/issues/issue-27282-move-ref-mut-into-guard.rs b/src/test/ui/issues/issue-27282-move-ref-mut-into-guard.rs
index e570b04a2bead..afa0ba780de46 100644
--- a/src/test/ui/issues/issue-27282-move-ref-mut-into-guard.rs
+++ b/src/test/ui/issues/issue-27282-move-ref-mut-into-guard.rs
@@ -1,11 +1,6 @@
 // Issue 27282: Example 1: This sidesteps the AST checks disallowing
 // mutable borrows in match guards by hiding the mutable borrow in a
 // guard behind a move (of the ref mut pattern id) within a closure.
-//
-// This example is not rejected by AST borrowck (and then reliably
-// segfaults when executed).
-
-#![feature(nll)]
 
 fn main() {
     match Some(&4) {
diff --git a/src/test/ui/issues/issue-27282-move-ref-mut-into-guard.stderr b/src/test/ui/issues/issue-27282-move-ref-mut-into-guard.stderr
index c5a9dd98a1596..30cf0d66afaff 100644
--- a/src/test/ui/issues/issue-27282-move-ref-mut-into-guard.stderr
+++ b/src/test/ui/issues/issue-27282-move-ref-mut-into-guard.stderr
@@ -1,5 +1,5 @@
 error[E0507]: cannot move out of `foo` in pattern guard
-  --> $DIR/issue-27282-move-ref-mut-into-guard.rs:14:19
+  --> $DIR/issue-27282-move-ref-mut-into-guard.rs:9:19
    |
 LL |             if { (|| { let bar = foo; bar.take() })(); false } => {},
    |                   ^^             ---
diff --git a/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-1.rs b/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-1.rs
index 3fb13d66ccb32..d17d6f07f6870 100644
--- a/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-1.rs
+++ b/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-1.rs
@@ -9,8 +9,6 @@
 // diverges, and therefore a single final fake-read at the very end
 // after the final match arm would not suffice.
 
-#![feature(nll)]
-
 struct ForceFnOnce;
 
 fn main() {
diff --git a/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-1.stderr b/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-1.stderr
index 199407ad77463..188f0b25c3084 100644
--- a/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-1.stderr
+++ b/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-1.stderr
@@ -1,5 +1,5 @@
 error[E0510]: cannot mutably borrow `x` in match guard
-  --> $DIR/issue-27282-mutate-before-diverging-arm-1.rs:23:14
+  --> $DIR/issue-27282-mutate-before-diverging-arm-1.rs:21:14
    |
 LL |     match x {
    |           - value is immutable in match guard
diff --git a/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-2.rs b/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-2.rs
index f5eaae925db01..9c3e7e9978ec7 100644
--- a/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-2.rs
+++ b/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-2.rs
@@ -13,8 +13,6 @@
 // occurs in the pattern-match itself, and not in the guard
 // expression.
 
-#![feature(nll)]
-
 struct ForceFnOnce;
 
 fn main() {
diff --git a/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-2.stderr b/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-2.stderr
index 3c72cb02015a0..f0a3151f4e12f 100644
--- a/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-2.stderr
+++ b/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-2.stderr
@@ -1,5 +1,5 @@
 error[E0510]: cannot mutably borrow `x` in match guard
-  --> $DIR/issue-27282-mutate-before-diverging-arm-2.rs:28:18
+  --> $DIR/issue-27282-mutate-before-diverging-arm-2.rs:26:18
    |
 LL |     match x {
    |           - value is immutable in match guard
diff --git a/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-3.rs b/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-3.rs
index 4cf5bcd6b4f68..cff9e963e2725 100644
--- a/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-3.rs
+++ b/src/test/ui/issues/issue-27282-mutate-before-diverging-arm-3.rs
@@ -8,7 +8,7 @@
 // This case is interesting because a borrow of **x is untracked, because **x is
 // immutable. However, for matches we care that **x refers to the same value
 // until we have chosen a match arm.
-#![feature(nll)]
+
 struct ForceFnOnce;
 fn main() {
     let mut x = &mut &Some(&2);
diff --git a/src/test/ui/issues/issue-29723.rs b/src/test/ui/issues/issue-29723.rs
index 41db52a1fadac..ce91022f093d4 100644
--- a/src/test/ui/issues/issue-29723.rs
+++ b/src/test/ui/issues/issue-29723.rs
@@ -1,5 +1,3 @@
-#![feature(nll)]
-
 // test for https://github.com/rust-lang/rust/issues/29723
 
 fn main() {
diff --git a/src/test/ui/issues/issue-29723.stderr b/src/test/ui/issues/issue-29723.stderr
index 7928af5d5a5cd..04915ab5f9510 100644
--- a/src/test/ui/issues/issue-29723.stderr
+++ b/src/test/ui/issues/issue-29723.stderr
@@ -1,5 +1,5 @@
 error[E0382]: use of moved value: `s`
-  --> $DIR/issue-29723.rs:12:13
+  --> $DIR/issue-29723.rs:10:13
    |
 LL |     let s = String::new();
    |         - move occurs because `s` has type `std::string::String`, which does not implement the `Copy` trait
diff --git a/src/test/ui/issues/issue-40510-1.migrate.stderr b/src/test/ui/issues/issue-40510-1.migrate.stderr
index 28aaa2a797e05..776a724d3106a 100644
--- a/src/test/ui/issues/issue-40510-1.migrate.stderr
+++ b/src/test/ui/issues/issue-40510-1.migrate.stderr
@@ -1,4 +1,4 @@
-warning: captured variable cannot escape `FnMut` closure body
+error: captured variable cannot escape `FnMut` closure body
   --> $DIR/issue-40510-1.rs:11:9
    |
 LL |     || {
@@ -8,15 +8,6 @@ LL |         &mut x
    |
    = note: `FnMut` closures only have access to their captured variables while they are executing...
    = note: ...therefore, they cannot allow references to captured variables to escape
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
-
-error: compilation successful
-  --> $DIR/issue-40510-1.rs:20:1
-   |
-LL | fn main() {}
-   | ^^^^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-40510-1.nll.stderr b/src/test/ui/issues/issue-40510-1.nll.stderr
deleted file mode 100644
index 776a724d3106a..0000000000000
--- a/src/test/ui/issues/issue-40510-1.nll.stderr
+++ /dev/null
@@ -1,13 +0,0 @@
-error: captured variable cannot escape `FnMut` closure body
-  --> $DIR/issue-40510-1.rs:11:9
-   |
-LL |     || {
-   |      - inferred to be a `FnMut` closure
-LL |         &mut x
-   |         ^^^^^^ returns a reference to a captured variable which escapes the closure body
-   |
-   = note: `FnMut` closures only have access to their captured variables while they are executing...
-   = note: ...therefore, they cannot allow references to captured variables to escape
-
-error: aborting due to previous error
-
diff --git a/src/test/ui/issues/issue-40510-1.rs b/src/test/ui/issues/issue-40510-1.rs
index 6ecbeefd88115..ca53dcd9b41fa 100644
--- a/src/test/ui/issues/issue-40510-1.rs
+++ b/src/test/ui/issues/issue-40510-1.rs
@@ -1,21 +1,12 @@
-#![feature(rustc_attrs)]
 #![allow(unused)]
 
-// revisions: migrate nll
-#![cfg_attr(nll, feature(nll))]
-
 fn f() {
     let mut x: Box<()> = Box::new(());
 
     || {
         &mut x
     };
-    //[migrate]~^^ WARNING captured variable cannot escape `FnMut` closure body
-    //[migrate]~| WARNING this error has been downgraded to a warning
-    //[migrate]~| WARNING this warning will become a hard error in the future
-    //[nll]~^^^^^ ERROR captured variable cannot escape `FnMut` closure body
+    //~^^ ERROR captured variable cannot escape `FnMut` closure body
 }
 
-#[rustc_error]
 fn main() {}
-//[migrate]~^ ERROR
diff --git a/src/test/ui/issues/issue-40510-1.migrate.nll.stderr b/src/test/ui/issues/issue-40510-1.stderr
similarity index 93%
rename from src/test/ui/issues/issue-40510-1.migrate.nll.stderr
rename to src/test/ui/issues/issue-40510-1.stderr
index 776a724d3106a..f4fda0abc2049 100644
--- a/src/test/ui/issues/issue-40510-1.migrate.nll.stderr
+++ b/src/test/ui/issues/issue-40510-1.stderr
@@ -1,5 +1,5 @@
 error: captured variable cannot escape `FnMut` closure body
-  --> $DIR/issue-40510-1.rs:11:9
+  --> $DIR/issue-40510-1.rs:7:9
    |
 LL |     || {
    |      - inferred to be a `FnMut` closure
diff --git a/src/test/ui/issues/issue-40510-3.migrate.stderr b/src/test/ui/issues/issue-40510-3.migrate.stderr
index f00690efc312c..a49475a8570a1 100644
--- a/src/test/ui/issues/issue-40510-3.migrate.stderr
+++ b/src/test/ui/issues/issue-40510-3.migrate.stderr
@@ -1,4 +1,4 @@
-warning: captured variable cannot escape `FnMut` closure body
+error: captured variable cannot escape `FnMut` closure body
   --> $DIR/issue-40510-3.rs:11:9
    |
 LL |       || {
@@ -10,15 +10,6 @@ LL | |         }
    |
    = note: `FnMut` closures only have access to their captured variables while they are executing...
    = note: ...therefore, they cannot allow references to captured variables to escape
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
-
-error: compilation successful
-  --> $DIR/issue-40510-3.rs:22:1
-   |
-LL | fn main() {}
-   | ^^^^^^^^^^^^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/issues/issue-40510-3.nll.stderr b/src/test/ui/issues/issue-40510-3.nll.stderr
deleted file mode 100644
index a49475a8570a1..0000000000000
--- a/src/test/ui/issues/issue-40510-3.nll.stderr
+++ /dev/null
@@ -1,15 +0,0 @@
-error: captured variable cannot escape `FnMut` closure body
-  --> $DIR/issue-40510-3.rs:11:9
-   |
-LL |       || {
-   |        - inferred to be a `FnMut` closure
-LL | /         || {
-LL | |             x.push(())
-LL | |         }
-   | |_________^ returns a closure that contains a reference to a captured variable, which then escapes the closure body
-   |
-   = note: `FnMut` closures only have access to their captured variables while they are executing...
-   = note: ...therefore, they cannot allow references to captured variables to escape
-
-error: aborting due to previous error
-
diff --git a/src/test/ui/issues/issue-40510-3.rs b/src/test/ui/issues/issue-40510-3.rs
index 205d982363128..181263adcbfa8 100644
--- a/src/test/ui/issues/issue-40510-3.rs
+++ b/src/test/ui/issues/issue-40510-3.rs
@@ -1,9 +1,5 @@
-#![feature(rustc_attrs)]
 #![allow(unused)]
 
-// revisions: migrate nll
-#![cfg_attr(nll, feature(nll))]
-
 fn f() {
     let mut x: Vec<()> = Vec::new();
 
@@ -11,13 +7,8 @@ fn f() {
         || {
             x.push(())
         }
-        //[migrate]~^^^ WARNING captured variable cannot escape `FnMut` closure body
-        //[migrate]~| WARNING this error has been downgraded to a warning
-        //[migrate]~| WARNING this warning will become a hard error in the future
-        //[nll]~^^^^^^ ERROR captured variable cannot escape `FnMut` closure body
+        //~^^^ ERROR captured variable cannot escape `FnMut` closure body
     };
 }
 
-#[rustc_error]
 fn main() {}
-//[migrate]~^ ERROR
diff --git a/src/test/ui/issues/issue-40510-3.migrate.nll.stderr b/src/test/ui/issues/issue-40510-3.stderr
similarity index 94%
rename from src/test/ui/issues/issue-40510-3.migrate.nll.stderr
rename to src/test/ui/issues/issue-40510-3.stderr
index a49475a8570a1..4bc7d0f5deac5 100644
--- a/src/test/ui/issues/issue-40510-3.migrate.nll.stderr
+++ b/src/test/ui/issues/issue-40510-3.stderr
@@ -1,5 +1,5 @@
 error: captured variable cannot escape `FnMut` closure body
-  --> $DIR/issue-40510-3.rs:11:9
+  --> $DIR/issue-40510-3.rs:7:9
    |
 LL |       || {
    |        - inferred to be a `FnMut` closure
diff --git a/src/test/ui/issues/issue-45157.rs b/src/test/ui/issues/issue-45157.rs
index 22ea254a769e8..bd18784289fe2 100644
--- a/src/test/ui/issues/issue-45157.rs
+++ b/src/test/ui/issues/issue-45157.rs
@@ -1,5 +1,4 @@
 #![allow(unused)]
-#![feature(nll)]
 
 // ignore-tidy-linelength
 
diff --git a/src/test/ui/issues/issue-45157.stderr b/src/test/ui/issues/issue-45157.stderr
index fbfa1d199566e..1b879e0b48c87 100644
--- a/src/test/ui/issues/issue-45157.stderr
+++ b/src/test/ui/issues/issue-45157.stderr
@@ -1,5 +1,5 @@
 error[E0502]: cannot borrow `u` (via `u.z.c`) as immutable because it is also borrowed as mutable (via `u.s.a`)
-  --> $DIR/issue-45157.rs:29:20
+  --> $DIR/issue-45157.rs:28:20
    |
 LL |         let mref = &mut u.s.a;
    |                    ---------- mutable borrow occurs here (via `u.s.a`)
diff --git a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.migrate.stderr b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.migrate.stderr
deleted file mode 100644
index 2e99572d01828..0000000000000
--- a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.migrate.stderr
+++ /dev/null
@@ -1,60 +0,0 @@
-warning[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:52:5
-   |
-LL | fn scribbled<'a>(s: Scribble<'a>) -> &'a mut u32 {
-   |              -- lifetime `'a` defined here
-LL |     &mut *s.0
-   |     ^^^^^^^^^ returning this value requires that `*s.0` is borrowed for `'a`
-...
-LL | }
-   | - here, drop of `s` needs exclusive access to `*s.0`, because the type `Scribble<'_>` implements the `Drop` trait
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
-
-warning[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:63:5
-   |
-LL | fn boxed_scribbled<'a>(s: Box<Scribble<'a>>) -> &'a mut u32 {
-   |                    -- lifetime `'a` defined here
-LL |     &mut *(*s).0
-   |     ^^^^^^^^^^^^ returning this value requires that `*s.0` is borrowed for `'a`
-...
-LL | }
-   | - here, drop of `s` needs exclusive access to `*s.0`, because the type `Scribble<'_>` implements the `Drop` trait
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
-
-warning[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:74:5
-   |
-LL | fn boxed_boxed_scribbled<'a>(s: Box<Box<Scribble<'a>>>) -> &'a mut u32 {
-   |                          -- lifetime `'a` defined here
-LL |     &mut *(**s).0
-   |     ^^^^^^^^^^^^^ returning this value requires that `*s.0` is borrowed for `'a`
-...
-LL | }
-   | - here, drop of `s` needs exclusive access to `*s.0`, because the type `Scribble<'_>` implements the `Drop` trait
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
-
-error: compilation successful
-  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:81:1
-   |
-LL | / fn main() {
-LL | |     let mut x = 1;
-LL | |     {
-LL | |         let mut long_lived = Scribble(&mut x);
-...  |
-LL | |     *boxed_boxed_scribbled(Box::new(Box::new(Scribble(&mut x)))) += 10;
-LL | | }
-   | |_^
-
-error: aborting due to previous error
-
-For more information about this error, try `rustc --explain E0713`.
diff --git a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.rs b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.rs
index 9f261884f3d2d..e9daf39262c2b 100644
--- a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.rs
+++ b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.rs
@@ -1,28 +1,15 @@
 // rust-lang/rust#45696: This test is checking that we *cannot* return
 // mutable borrows that would be scribbled over by destructors before
 // the return occurs.
-//
-// We will explicitly test NLL, and migration modes;
-// thus we will also skip the automated compare-mode=nll.
 
-// revisions: nll migrate
 // ignore-compare-mode-nll
 // ignore-compare-mode-polonius
 
-// This test is going to pass in the migrate revision, because the AST-borrowck
-// accepted this code in the past (see notes below). So we use `#[rustc_error]`
-// to keep the outcome as an error in all scenarios, and rely on the stderr
-// files to show what the actual behavior is. (See rust-lang/rust#49855.)
-#![feature(rustc_attrs)]
-
-#![cfg_attr(nll, feature(nll))]
-
 struct Scribble<'a>(&'a mut u32);
 
 impl<'a> Drop for Scribble<'a> { fn drop(&mut self) { *self.0 = 42; } }
 
-// this is okay, in both AST-borrowck and NLL: The `Scribble` here *has*
-// to strictly outlive `'a`
+// this is okay: The `Scribble` here *has* to strictly outlive `'a`
 fn borrowed_scribble<'a>(s: &'a mut Scribble) -> &'a mut u32 {
     &mut *s.0
 }
@@ -44,41 +31,21 @@ fn boxed_boxed_borrowed_scribble<'a>(s: Box<Box<&'a mut Scribble>>) -> &'a mut u
 // * (Maybe in the future the two-phase borrows system will be
 //   extended to support this case. But for now, it is an error in
 //   NLL, even with two-phase borrows.)
-//
-// In any case, the AST-borrowck was not smart enough to know that
-// this should be an error. (Which is perhaps the essence of why
-// rust-lang/rust#45696 arose in the first place.)
 fn scribbled<'a>(s: Scribble<'a>) -> &'a mut u32 {
-    &mut *s.0 //[nll]~ ERROR borrow may still be in use when destructor runs [E0713]
-    //[migrate]~^ WARNING borrow may still be in use when destructor runs [E0713]
-    //[migrate]~| WARNING this error has been downgraded to a warning for backwards compatibility
-    //[migrate]~| WARNING this represents potential undefined behavior in your code
+    &mut *s.0 //~ ERROR borrow may still be in use when destructor runs [E0713]
 }
 
 // This, by analogy to previous case, is *also* not okay.
-//
-// (But again, AST-borrowck was not smart enogh to know that this
-// should be an error.)
 fn boxed_scribbled<'a>(s: Box<Scribble<'a>>) -> &'a mut u32 {
-    &mut *(*s).0 //[nll]~ ERROR borrow may still be in use when destructor runs [E0713]
-    //[migrate]~^ WARNING borrow may still be in use when destructor runs [E0713]
-    //[migrate]~| WARNING this error has been downgraded to a warning for backwards compatibility
-    //[migrate]~| WARNING this represents potential undefined behavior in your code
+    &mut *(*s).0 //~ ERROR borrow may still be in use when destructor runs [E0713]
 }
 
 // This, by analogy to previous case, is *also* not okay.
-//
-// (But again, AST-borrowck was not smart enogh to know that this
-// should be an error.)
 fn boxed_boxed_scribbled<'a>(s: Box<Box<Scribble<'a>>>) -> &'a mut u32 {
-    &mut *(**s).0 //[nll]~ ERROR borrow may still be in use when destructor runs [E0713]
-    //[migrate]~^ WARNING borrow may still be in use when destructor runs [E0713]
-    //[migrate]~| WARNING this error has been downgraded to a warning for backwards compatibility
-    //[migrate]~| WARNING this represents potential undefined behavior in your code
+    &mut *(**s).0 //~ ERROR borrow may still be in use when destructor runs [E0713]
 }
 
-#[rustc_error]
-fn main() { //[migrate]~ ERROR compilation successful
+fn main() {
     let mut x = 1;
     {
         let mut long_lived = Scribble(&mut x);
diff --git a/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.stderr b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.stderr
new file mode 100644
index 0000000000000..18aa38899cb8e
--- /dev/null
+++ b/src/test/ui/issues/issue-45696-scribble-on-boxed-borrow.stderr
@@ -0,0 +1,33 @@
+error[E0713]: borrow may still be in use when destructor runs
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:35:5
+   |
+LL | fn scribbled<'a>(s: Scribble<'a>) -> &'a mut u32 {
+   |              -- lifetime `'a` defined here
+LL |     &mut *s.0
+   |     ^^^^^^^^^ returning this value requires that `*s.0` is borrowed for `'a`
+LL | }
+   | - here, drop of `s` needs exclusive access to `*s.0`, because the type `Scribble<'_>` implements the `Drop` trait
+
+error[E0713]: borrow may still be in use when destructor runs
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:40:5
+   |
+LL | fn boxed_scribbled<'a>(s: Box<Scribble<'a>>) -> &'a mut u32 {
+   |                    -- lifetime `'a` defined here
+LL |     &mut *(*s).0
+   |     ^^^^^^^^^^^^ returning this value requires that `*s.0` is borrowed for `'a`
+LL | }
+   | - here, drop of `s` needs exclusive access to `*s.0`, because the type `Scribble<'_>` implements the `Drop` trait
+
+error[E0713]: borrow may still be in use when destructor runs
+  --> $DIR/issue-45696-scribble-on-boxed-borrow.rs:45:5
+   |
+LL | fn boxed_boxed_scribbled<'a>(s: Box<Box<Scribble<'a>>>) -> &'a mut u32 {
+   |                          -- lifetime `'a` defined here
+LL |     &mut *(**s).0
+   |     ^^^^^^^^^^^^^ returning this value requires that `*s.0` is borrowed for `'a`
+LL | }
+   | - here, drop of `s` needs exclusive access to `*s.0`, because the type `Scribble<'_>` implements the `Drop` trait
+
+error: aborting due to 3 previous errors
+
+For more information about this error, try `rustc --explain E0713`.
diff --git a/src/test/ui/issues/issue-49824.nll.stderr b/src/test/ui/issues/issue-49824.nll.stderr
deleted file mode 100644
index 9c6f8d4532a70..0000000000000
--- a/src/test/ui/issues/issue-49824.nll.stderr
+++ /dev/null
@@ -1,18 +0,0 @@
-error: captured variable cannot escape `FnMut` closure body
-  --> $DIR/issue-49824.rs:10:9
-   |
-LL |       || {
-   |        - inferred to be a `FnMut` closure
-LL | /         || {
-LL | |
-LL | |
-LL | |
-LL | |             let _y = &mut x;
-LL | |         }
-   | |_________^ returns a closure that contains a reference to a captured variable, which then escapes the closure body
-   |
-   = note: `FnMut` closures only have access to their captured variables while they are executing...
-   = note: ...therefore, they cannot allow references to captured variables to escape
-
-error: aborting due to previous error
-
diff --git a/src/test/ui/issues/issue-49824.rs b/src/test/ui/issues/issue-49824.rs
index b0d01b3d98d51..bc1cd6856bc92 100644
--- a/src/test/ui/issues/issue-49824.rs
+++ b/src/test/ui/issues/issue-49824.rs
@@ -1,16 +1,8 @@
-#![feature(rustc_attrs)]
-
-// This test checks that a warning occurs with migrate mode.
-
-#[rustc_error]
 fn main() {
-    //~^ ERROR compilation successful
     let mut x = 0;
     || {
         || {
-        //~^ WARNING captured variable cannot escape `FnMut` closure body
-        //~| WARNING this error has been downgraded to a warning
-        //~| WARNING this warning will become a hard error in the future
+        //~^ ERROR captured variable cannot escape `FnMut` closure body
             let _y = &mut x;
         }
     };
diff --git a/src/test/ui/issues/issue-49824.stderr b/src/test/ui/issues/issue-49824.stderr
index d5f1af88e133a..6b486aafcdf40 100644
--- a/src/test/ui/issues/issue-49824.stderr
+++ b/src/test/ui/issues/issue-49824.stderr
@@ -1,33 +1,16 @@
-warning: captured variable cannot escape `FnMut` closure body
-  --> $DIR/issue-49824.rs:10:9
+error: captured variable cannot escape `FnMut` closure body
+  --> $DIR/issue-49824.rs:4:9
    |
 LL |       || {
    |        - inferred to be a `FnMut` closure
 LL | /         || {
 LL | |
-LL | |
-LL | |
 LL | |             let _y = &mut x;
 LL | |         }
    | |_________^ returns a closure that contains a reference to a captured variable, which then escapes the closure body
    |
    = note: `FnMut` closures only have access to their captured variables while they are executing...
    = note: ...therefore, they cannot allow references to captured variables to escape
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
-
-error: compilation successful
-  --> $DIR/issue-49824.rs:6:1
-   |
-LL | / fn main() {
-LL | |
-LL | |     let mut x = 0;
-LL | |     || {
-...  |
-LL | |     };
-LL | | }
-   | |_^
 
 error: aborting due to previous error
 
diff --git a/src/test/ui/never-from-impl-is-reserved.rs b/src/test/ui/never-from-impl-is-reserved.rs
new file mode 100644
index 0000000000000..9d16015bdc129
--- /dev/null
+++ b/src/test/ui/never-from-impl-is-reserved.rs
@@ -0,0 +1,12 @@
+// check that the `for<T> T: From<!>` impl is reserved
+
+#![feature(never_type)]
+
+pub struct MyFoo;
+pub trait MyTrait {}
+
+impl MyTrait for MyFoo {}
+// This will conflict with the first impl if we impl `for<T> T: From<!>`.
+impl<T> MyTrait for T where T: From<!> {} //~ ERROR conflicting implementation
+
+fn main() {}
diff --git a/src/test/ui/never-from-impl-is-reserved.stderr b/src/test/ui/never-from-impl-is-reserved.stderr
new file mode 100644
index 0000000000000..8b8d0f4ea73be
--- /dev/null
+++ b/src/test/ui/never-from-impl-is-reserved.stderr
@@ -0,0 +1,14 @@
+error[E0119]: conflicting implementations of trait `MyTrait` for type `MyFoo`:
+  --> $DIR/never-from-impl-is-reserved.rs:10:1
+   |
+LL | impl MyTrait for MyFoo {}
+   | ---------------------- first implementation here
+LL | // This will conflict with the first impl if we impl `for<T> T: From<!>`.
+LL | impl<T> MyTrait for T where T: From<!> {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `MyFoo`
+   |
+   = note: permitting this impl would forbid us from adding `impl<T> From<!> for T` later; see rust-lang/rust#64715 for details
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0119`.
diff --git a/src/test/ui/nll/borrowed-match-issue-45045.rs b/src/test/ui/nll/borrowed-match-issue-45045.rs
index 59516d8b444d1..0cd8e956d309f 100644
--- a/src/test/ui/nll/borrowed-match-issue-45045.rs
+++ b/src/test/ui/nll/borrowed-match-issue-45045.rs
@@ -1,7 +1,5 @@
 // Regression test for issue #45045
 
-#![feature(nll)]
-
 enum Xyz {
     A,
     B,
diff --git a/src/test/ui/nll/borrowed-match-issue-45045.stderr b/src/test/ui/nll/borrowed-match-issue-45045.stderr
index f8d4d56621deb..1607304e6716b 100644
--- a/src/test/ui/nll/borrowed-match-issue-45045.stderr
+++ b/src/test/ui/nll/borrowed-match-issue-45045.stderr
@@ -1,5 +1,5 @@
 error[E0503]: cannot use `e` because it was mutably borrowed
-  --> $DIR/borrowed-match-issue-45045.rs:15:9
+  --> $DIR/borrowed-match-issue-45045.rs:13:9
    |
 LL |     let f = &mut e;
    |             ------ borrow of `e` occurs here
diff --git a/src/test/ui/nll/borrowed-referent-issue-38899.rs b/src/test/ui/nll/borrowed-referent-issue-38899.rs
index d4b05fb793160..1fe1332832a14 100644
--- a/src/test/ui/nll/borrowed-referent-issue-38899.rs
+++ b/src/test/ui/nll/borrowed-referent-issue-38899.rs
@@ -1,7 +1,5 @@
 // Regression test for issue #38899
 
-#![feature(nll)]
-
 pub struct Block<'a> {
     current: &'a u8,
     unrelated: &'a u8,
diff --git a/src/test/ui/nll/borrowed-referent-issue-38899.stderr b/src/test/ui/nll/borrowed-referent-issue-38899.stderr
index 38a6e27a0e560..16588cbcfb285 100644
--- a/src/test/ui/nll/borrowed-referent-issue-38899.stderr
+++ b/src/test/ui/nll/borrowed-referent-issue-38899.stderr
@@ -1,5 +1,5 @@
 error[E0502]: cannot borrow `*block.current` as immutable because it is also borrowed as mutable
-  --> $DIR/borrowed-referent-issue-38899.rs:13:21
+  --> $DIR/borrowed-referent-issue-38899.rs:11:21
    |
 LL |     let x = &mut block;
    |             ---------- mutable borrow occurs here
diff --git a/src/test/ui/nll/do-not-ignore-lifetime-bounds-in-copy.rs b/src/test/ui/nll/do-not-ignore-lifetime-bounds-in-copy.rs
index 2a1321c25510f..99922cc51b0d1 100644
--- a/src/test/ui/nll/do-not-ignore-lifetime-bounds-in-copy.rs
+++ b/src/test/ui/nll/do-not-ignore-lifetime-bounds-in-copy.rs
@@ -1,7 +1,5 @@
 // Test that the 'static bound from the Copy impl is respected. Regression test for #29149.
 
-#![feature(nll)]
-
 #[derive(Clone)] struct Foo<'a>(&'a u32);
 impl Copy for Foo<'static> {}
 
diff --git a/src/test/ui/nll/do-not-ignore-lifetime-bounds-in-copy.stderr b/src/test/ui/nll/do-not-ignore-lifetime-bounds-in-copy.stderr
index bf5c571b455b3..b811ba4fd0cd2 100644
--- a/src/test/ui/nll/do-not-ignore-lifetime-bounds-in-copy.stderr
+++ b/src/test/ui/nll/do-not-ignore-lifetime-bounds-in-copy.stderr
@@ -1,5 +1,5 @@
 error[E0597]: `s` does not live long enough
-  --> $DIR/do-not-ignore-lifetime-bounds-in-copy.rs:10:17
+  --> $DIR/do-not-ignore-lifetime-bounds-in-copy.rs:8:17
    |
 LL |     let a = Foo(&s);
    |                 ^^ borrowed value does not live long enough
diff --git a/src/test/ui/nll/enum-drop-access.rs b/src/test/ui/nll/enum-drop-access.rs
index dc436d20fd857..5ef0c3fe73dbf 100644
--- a/src/test/ui/nll/enum-drop-access.rs
+++ b/src/test/ui/nll/enum-drop-access.rs
@@ -1,5 +1,3 @@
-#![feature(nll)]
-
 enum DropOption<T> {
     Some(T),
     None,
diff --git a/src/test/ui/nll/enum-drop-access.stderr b/src/test/ui/nll/enum-drop-access.stderr
index 699179fd52fd4..a532ae121a6ef 100644
--- a/src/test/ui/nll/enum-drop-access.stderr
+++ b/src/test/ui/nll/enum-drop-access.stderr
@@ -1,5 +1,5 @@
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/enum-drop-access.rs:15:31
+  --> $DIR/enum-drop-access.rs:13:31
    |
 LL | fn drop_enum(opt: DropOption<&mut i32>) -> Option<&mut i32> {
    |                              - let's call the lifetime of this reference `'1`
@@ -13,7 +13,7 @@ LL | }
    | - here, drop of `opt` needs exclusive access to `*opt.0`, because the type `DropOption<&mut i32>` implements the `Drop` trait
 
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/enum-drop-access.rs:24:36
+  --> $DIR/enum-drop-access.rs:22:36
    |
 LL | fn optional_drop_enum(opt: Option<DropOption<&mut i32>>) -> Option<&mut i32> {
    |                                              - let's call the lifetime of this reference `'1`
diff --git a/src/test/ui/nll/issue-21232-partial-init-and-use.rs b/src/test/ui/nll/issue-21232-partial-init-and-use.rs
index 7da47c85f5450..1836f766cc7ef 100644
--- a/src/test/ui/nll/issue-21232-partial-init-and-use.rs
+++ b/src/test/ui/nll/issue-21232-partial-init-and-use.rs
@@ -12,8 +12,6 @@
 // tests that are meant to continue failing to compile once
 // rust-lang/rust#54987 is implemented.
 
-#![feature(nll)]
-
 struct S<Y> {
     x: u32,
 
diff --git a/src/test/ui/nll/issue-21232-partial-init-and-use.stderr b/src/test/ui/nll/issue-21232-partial-init-and-use.stderr
index 32147898320c0..9e69262b38900 100644
--- a/src/test/ui/nll/issue-21232-partial-init-and-use.stderr
+++ b/src/test/ui/nll/issue-21232-partial-init-and-use.stderr
@@ -1,17 +1,17 @@
 error[E0381]: assign to part of possibly-uninitialized variable: `s`
-  --> $DIR/issue-21232-partial-init-and-use.rs:99:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:97:5
    |
 LL |     s.x = 10; s.y = Box::new(20);
    |     ^^^^^^^^ use of possibly-uninitialized `s`
 
 error[E0381]: assign to part of possibly-uninitialized variable: `t`
-  --> $DIR/issue-21232-partial-init-and-use.rs:106:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:104:5
    |
 LL |     t.0 = 10; t.1 = Box::new(20);
    |     ^^^^^^^^ use of possibly-uninitialized `t`
 
 error[E0382]: assign to part of moved value: `s`
-  --> $DIR/issue-21232-partial-init-and-use.rs:113:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:111:5
    |
 LL |     let mut s: S<B> = S::new(); drop(s);
    |         -----                        - value moved here
@@ -21,7 +21,7 @@ LL |     s.x = 10; s.y = Box::new(20);
    |     ^^^^^^^^ value partially assigned here after move
 
 error[E0382]: assign to part of moved value: `t`
-  --> $DIR/issue-21232-partial-init-and-use.rs:120:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:118:5
    |
 LL |     let mut t: T = (0, Box::new(0)); drop(t);
    |         -----                             - value moved here
@@ -31,19 +31,19 @@ LL |     t.0 = 10; t.1 = Box::new(20);
    |     ^^^^^^^^ value partially assigned here after move
 
 error[E0381]: assign to part of possibly-uninitialized variable: `s`
-  --> $DIR/issue-21232-partial-init-and-use.rs:127:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:125:5
    |
 LL |     s.x = 10;
    |     ^^^^^^^^ use of possibly-uninitialized `s`
 
 error[E0381]: assign to part of possibly-uninitialized variable: `t`
-  --> $DIR/issue-21232-partial-init-and-use.rs:134:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:132:5
    |
 LL |     t.0 = 10;
    |     ^^^^^^^^ use of possibly-uninitialized `t`
 
 error[E0382]: assign to part of moved value: `s`
-  --> $DIR/issue-21232-partial-init-and-use.rs:141:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:139:5
    |
 LL |     let mut s: S<B> = S::new(); drop(s);
    |         -----                        - value moved here
@@ -53,7 +53,7 @@ LL |     s.x = 10;
    |     ^^^^^^^^ value partially assigned here after move
 
 error[E0382]: assign to part of moved value: `t`
-  --> $DIR/issue-21232-partial-init-and-use.rs:148:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:146:5
    |
 LL |     let mut t: T = (0, Box::new(0)); drop(t);
    |         -----                             - value moved here
@@ -63,31 +63,31 @@ LL |     t.0 = 10;
    |     ^^^^^^^^ value partially assigned here after move
 
 error[E0381]: assign to part of possibly-uninitialized variable: `s`
-  --> $DIR/issue-21232-partial-init-and-use.rs:155:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:153:5
    |
 LL |     s.x = 10;
    |     ^^^^^^^^ use of possibly-uninitialized `s`
 
 error[E0381]: assign to part of possibly-uninitialized variable: `t`
-  --> $DIR/issue-21232-partial-init-and-use.rs:162:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:160:5
    |
 LL |     t.0 = 10;
    |     ^^^^^^^^ use of possibly-uninitialized `t`
 
 error[E0381]: assign to part of possibly-uninitialized variable: `q`
-  --> $DIR/issue-21232-partial-init-and-use.rs:178:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:176:5
    |
 LL |     q.r.f.x = 10; q.r.f.y = Box::new(20);
    |     ^^^^^^^^^^^^ use of possibly-uninitialized `q.r.f`
 
 error[E0381]: assign to part of possibly-uninitialized variable: `q`
-  --> $DIR/issue-21232-partial-init-and-use.rs:185:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:183:5
    |
 LL |     q.r.f.0 = 10; q.r.f.1 = Box::new(20);
    |     ^^^^^^^^^^^^ use of possibly-uninitialized `q.r.f`
 
 error[E0382]: assign to part of moved value: `q.r`
-  --> $DIR/issue-21232-partial-init-and-use.rs:192:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:190:5
    |
 LL |     let mut q: Q<S<B>> = Q::new(S::new()); drop(q.r);
    |                                                 --- value moved here
@@ -97,7 +97,7 @@ LL |     q.r.f.x = 10; q.r.f.y = Box::new(20);
    = note: move occurs because `q.r` has type `R<S<std::boxed::Box<u32>>>`, which does not implement the `Copy` trait
 
 error[E0382]: assign to part of moved value: `q.r`
-  --> $DIR/issue-21232-partial-init-and-use.rs:199:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:197:5
    |
 LL |     let mut q: Q<T> = Q::new((0, Box::new(0))); drop(q.r);
    |                                                      --- value moved here
@@ -107,19 +107,19 @@ LL |     q.r.f.0 = 10; q.r.f.1 = Box::new(20);
    = note: move occurs because `q.r` has type `R<(u32, std::boxed::Box<u32>)>`, which does not implement the `Copy` trait
 
 error[E0381]: assign to part of possibly-uninitialized variable: `q`
-  --> $DIR/issue-21232-partial-init-and-use.rs:206:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:204:5
    |
 LL |     q.r.f.x = 10;
    |     ^^^^^^^^^^^^ use of possibly-uninitialized `q.r.f`
 
 error[E0381]: assign to part of possibly-uninitialized variable: `q`
-  --> $DIR/issue-21232-partial-init-and-use.rs:213:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:211:5
    |
 LL |     q.r.f.0 = 10;
    |     ^^^^^^^^^^^^ use of possibly-uninitialized `q.r.f`
 
 error[E0382]: assign to part of moved value: `q.r`
-  --> $DIR/issue-21232-partial-init-and-use.rs:220:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:218:5
    |
 LL |     let mut q: Q<S<B>> = Q::new(S::new()); drop(q.r);
    |                                                 --- value moved here
@@ -129,7 +129,7 @@ LL |     q.r.f.x = 10;
    = note: move occurs because `q.r` has type `R<S<std::boxed::Box<u32>>>`, which does not implement the `Copy` trait
 
 error[E0382]: assign to part of moved value: `q.r`
-  --> $DIR/issue-21232-partial-init-and-use.rs:227:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:225:5
    |
 LL |     let mut q: Q<T> = Q::new((0, Box::new(0))); drop(q.r);
    |                                                      --- value moved here
@@ -139,19 +139,19 @@ LL |     q.r.f.0 = 10;
    = note: move occurs because `q.r` has type `R<(u32, std::boxed::Box<u32>)>`, which does not implement the `Copy` trait
 
 error[E0381]: assign to part of possibly-uninitialized variable: `q`
-  --> $DIR/issue-21232-partial-init-and-use.rs:234:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:232:5
    |
 LL |     q.r.f.x = 10;
    |     ^^^^^^^^^^^^ use of possibly-uninitialized `q.r.f`
 
 error[E0381]: assign to part of possibly-uninitialized variable: `q`
-  --> $DIR/issue-21232-partial-init-and-use.rs:241:5
+  --> $DIR/issue-21232-partial-init-and-use.rs:239:5
    |
 LL |     q.r.f.0 = 10;
    |     ^^^^^^^^^^^^ use of possibly-uninitialized `q.r.f`
 
 error[E0382]: assign to part of moved value: `c`
-  --> $DIR/issue-21232-partial-init-and-use.rs:259:13
+  --> $DIR/issue-21232-partial-init-and-use.rs:257:13
    |
 LL |     let mut c = (1, "".to_owned());
    |         ----- move occurs because `c` has type `(i32, std::string::String)`, which does not implement the `Copy` trait
@@ -162,7 +162,7 @@ LL |             c.0 = 2;
    |             ^^^^^^^ value partially assigned here after move
 
 error[E0382]: assign to part of moved value: `c`
-  --> $DIR/issue-21232-partial-init-and-use.rs:269:13
+  --> $DIR/issue-21232-partial-init-and-use.rs:267:13
    |
 LL |     let mut c = (1, (1, "".to_owned()));
    |         ----- move occurs because `c` has type `(i32, (i32, std::string::String))`, which does not implement the `Copy` trait
@@ -173,7 +173,7 @@ LL |             (c.1).0 = 2;
    |             ^^^^^^^^^^^ value partially assigned here after move
 
 error[E0382]: assign to part of moved value: `c.1`
-  --> $DIR/issue-21232-partial-init-and-use.rs:277:13
+  --> $DIR/issue-21232-partial-init-and-use.rs:275:13
    |
 LL |         c2 => {
    |         -- value moved here
diff --git a/src/test/ui/nll/issue-27868.rs b/src/test/ui/nll/issue-27868.rs
index b5cf20bc9f965..e436b22dbaad4 100644
--- a/src/test/ui/nll/issue-27868.rs
+++ b/src/test/ui/nll/issue-27868.rs
@@ -1,7 +1,5 @@
 // Regression test for issue #27868
 
-#![feature(nll)]
-
 use std::ops::AddAssign;
 
 struct MyVec<T>(Vec<T>);
diff --git a/src/test/ui/nll/issue-27868.stderr b/src/test/ui/nll/issue-27868.stderr
index c83cb0b300b25..e0b3b5494d0a5 100644
--- a/src/test/ui/nll/issue-27868.stderr
+++ b/src/test/ui/nll/issue-27868.stderr
@@ -1,5 +1,5 @@
 error[E0506]: cannot assign to `vecvec` because it is borrowed
-  --> $DIR/issue-27868.rs:26:9
+  --> $DIR/issue-27868.rs:24:9
    |
 LL |       vecvec[0] += {
    |       ------
diff --git a/src/test/ui/nll/issue-31567.rs b/src/test/ui/nll/issue-31567.rs
index c57a07a54d58a..623954e6d5b94 100644
--- a/src/test/ui/nll/issue-31567.rs
+++ b/src/test/ui/nll/issue-31567.rs
@@ -2,8 +2,6 @@
 // causing region relations not to be enforced at all the places where
 // they have to be enforced.
 
-#![feature(nll)]
-
 struct VecWrapper<'a>(&'a mut S);
 
 struct S(Box<u32>);
diff --git a/src/test/ui/nll/issue-31567.stderr b/src/test/ui/nll/issue-31567.stderr
index d098ff82d34f0..7d43383e89fd7 100644
--- a/src/test/ui/nll/issue-31567.stderr
+++ b/src/test/ui/nll/issue-31567.stderr
@@ -1,5 +1,5 @@
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-31567.rs:12:26
+  --> $DIR/issue-31567.rs:10:26
    |
 LL | fn get_dangling<'a>(v: VecWrapper<'a>) -> &'a u32 {
    |                 -- lifetime `'a` defined here
diff --git a/src/test/ui/nll/issue-48238.rs b/src/test/ui/nll/issue-48238.rs
index 2e64ea72db28b..d2e9285fa4137 100644
--- a/src/test/ui/nll/issue-48238.rs
+++ b/src/test/ui/nll/issue-48238.rs
@@ -1,7 +1,5 @@
 // Regression test for issue #48238
 
-#![feature(nll)]
-
 fn use_val<'a>(val: &'a u8) -> &'a u8 {
     val
 }
diff --git a/src/test/ui/nll/issue-48238.stderr b/src/test/ui/nll/issue-48238.stderr
index 05a90eec05c3f..0aa1eedad9fd9 100644
--- a/src/test/ui/nll/issue-48238.stderr
+++ b/src/test/ui/nll/issue-48238.stderr
@@ -1,5 +1,5 @@
 error: lifetime may not live long enough
-  --> $DIR/issue-48238.rs:11:13
+  --> $DIR/issue-48238.rs:9:13
    |
 LL |     move || use_val(&orig);
    |     ------- ^^^^^^^^^^^^^^ returning this value requires that `'1` must outlive `'2`
diff --git a/src/test/ui/nll/issue-52059-report-when-borrow-and-drop-conflict.rs b/src/test/ui/nll/issue-52059-report-when-borrow-and-drop-conflict.rs
index 58416c31edde7..7ea1c445d143e 100644
--- a/src/test/ui/nll/issue-52059-report-when-borrow-and-drop-conflict.rs
+++ b/src/test/ui/nll/issue-52059-report-when-borrow-and-drop-conflict.rs
@@ -3,8 +3,6 @@
 // one of its fields, it is useful to be reminded of the significance
 // of the fact that the type implements Drop.
 
-#![feature(nll)]
-
 pub struct S<'a> { url: &'a mut String }
 
 impl<'a> Drop for S<'a> { fn drop(&mut self) { } }
diff --git a/src/test/ui/nll/issue-52059-report-when-borrow-and-drop-conflict.stderr b/src/test/ui/nll/issue-52059-report-when-borrow-and-drop-conflict.stderr
index ce48457abe7ec..1a1250ff9353f 100644
--- a/src/test/ui/nll/issue-52059-report-when-borrow-and-drop-conflict.stderr
+++ b/src/test/ui/nll/issue-52059-report-when-borrow-and-drop-conflict.stderr
@@ -1,5 +1,5 @@
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-52059-report-when-borrow-and-drop-conflict.rs:13:5
+  --> $DIR/issue-52059-report-when-borrow-and-drop-conflict.rs:11:5
    |
 LL | fn finish_1(s: S) -> &mut String {
    |             - has type `S<'1>`
@@ -9,7 +9,7 @@ LL | }
    | - here, drop of `s` needs exclusive access to `*s.url`, because the type `S<'_>` implements the `Drop` trait
 
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-52059-report-when-borrow-and-drop-conflict.rs:18:13
+  --> $DIR/issue-52059-report-when-borrow-and-drop-conflict.rs:16:13
    |
 LL | fn finish_2(s: S) -> &mut String {
    |             - has type `S<'1>`
@@ -19,7 +19,7 @@ LL | }
    | - here, drop of `s` needs exclusive access to `*s.url`, because the type `S<'_>` implements the `Drop` trait
 
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-52059-report-when-borrow-and-drop-conflict.rs:23:21
+  --> $DIR/issue-52059-report-when-borrow-and-drop-conflict.rs:21:21
    |
 LL | fn finish_3(s: S) -> &mut String {
    |             - has type `S<'1>`
@@ -29,7 +29,7 @@ LL | }
    | - here, drop of `s` needs exclusive access to `*s.url`, because the type `S<'_>` implements the `Drop` trait
 
 error[E0509]: cannot move out of type `S<'_>`, which implements the `Drop` trait
-  --> $DIR/issue-52059-report-when-borrow-and-drop-conflict.rs:28:13
+  --> $DIR/issue-52059-report-when-borrow-and-drop-conflict.rs:26:13
    |
 LL |     let p = s.url; p
    |             ^^^^^
diff --git a/src/test/ui/nll/issue-53040.rs b/src/test/ui/nll/issue-53040.rs
index 8ce24c8ede9ac..e4ee6e913f683 100644
--- a/src/test/ui/nll/issue-53040.rs
+++ b/src/test/ui/nll/issue-53040.rs
@@ -1,5 +1,3 @@
-#![feature(nll)]
-
 fn main() {
     let mut v: Vec<()> = Vec::new();
     || &mut v;
diff --git a/src/test/ui/nll/issue-53040.stderr b/src/test/ui/nll/issue-53040.stderr
index 9e7e63af87db1..7cba32c67432c 100644
--- a/src/test/ui/nll/issue-53040.stderr
+++ b/src/test/ui/nll/issue-53040.stderr
@@ -1,5 +1,5 @@
 error: captured variable cannot escape `FnMut` closure body
-  --> $DIR/issue-53040.rs:5:8
+  --> $DIR/issue-53040.rs:3:8
    |
 LL |     || &mut v;
    |      - ^^^^^^ returns a reference to a captured variable which escapes the closure body
diff --git a/src/test/ui/nll/issue-53773.rs b/src/test/ui/nll/issue-53773.rs
index 62e1631dcf36f..ed971b6ce0e1b 100644
--- a/src/test/ui/nll/issue-53773.rs
+++ b/src/test/ui/nll/issue-53773.rs
@@ -1,5 +1,3 @@
-#![feature(nll)]
-
 struct Archive;
 struct ArchiveIterator<'a> {
     x: &'a Archive,
diff --git a/src/test/ui/nll/issue-53773.stderr b/src/test/ui/nll/issue-53773.stderr
index 1933ef7a2dbc7..45831460e5238 100644
--- a/src/test/ui/nll/issue-53773.stderr
+++ b/src/test/ui/nll/issue-53773.stderr
@@ -1,5 +1,5 @@
 error[E0713]: borrow may still be in use when destructor runs
-  --> $DIR/issue-53773.rs:43:22
+  --> $DIR/issue-53773.rs:41:22
    |
 LL |         members.push(child.raw);
    |                      ^^^^^^^^^
diff --git a/src/test/ui/nll/issue-57100.rs b/src/test/ui/nll/issue-57100.rs
index f669fe00956ef..c7f3e9d730367 100644
--- a/src/test/ui/nll/issue-57100.rs
+++ b/src/test/ui/nll/issue-57100.rs
@@ -1,5 +1,4 @@
 #![allow(unused)]
-#![feature(nll)]
 
 // ignore-tidy-linelength
 
diff --git a/src/test/ui/nll/issue-57100.stderr b/src/test/ui/nll/issue-57100.stderr
index 5d5c86c34875c..5f733c14036b0 100644
--- a/src/test/ui/nll/issue-57100.stderr
+++ b/src/test/ui/nll/issue-57100.stderr
@@ -1,5 +1,5 @@
 error[E0502]: cannot borrow `r.r2_union.f3_union` (via `r.r2_union.f3_union.s2_leaf.l1_u8`) as immutable because it is also borrowed as mutable (via `r.r2_union.f3_union.s1_leaf.l1_u8`)
-  --> $DIR/issue-57100.rs:44:20
+  --> $DIR/issue-57100.rs:43:20
    |
 LL |         let mref = &mut r.r2_union.f3_union.s1_leaf.l1_u8;
    |                    -------------------------------------- mutable borrow occurs here (via `r.r2_union.f3_union.s1_leaf.l1_u8`)
@@ -13,7 +13,7 @@ LL |         println!("{} {}", mref, nref)
    = note: `r.r2_union.f3_union.s2_leaf.l1_u8` is a field of the union `Second`, so it overlaps the field `r.r2_union.f3_union.s1_leaf.l1_u8`
 
 error[E0502]: cannot borrow `r.r2_union` (via `r.r2_union.f1_leaf.l1_u8`) as immutable because it is also borrowed as mutable (via `r.r2_union.f2_leaf.l1_u8`)
-  --> $DIR/issue-57100.rs:62:20
+  --> $DIR/issue-57100.rs:61:20
    |
 LL |         let mref = &mut r.r2_union.f2_leaf.l1_u8;
    |                    ----------------------------- mutable borrow occurs here (via `r.r2_union.f2_leaf.l1_u8`)
diff --git a/src/test/ui/nll/match-guards-always-borrow.rs b/src/test/ui/nll/match-guards-always-borrow.rs
index d423730bdbc35..87dba187ba2c2 100644
--- a/src/test/ui/nll/match-guards-always-borrow.rs
+++ b/src/test/ui/nll/match-guards-always-borrow.rs
@@ -1,5 +1,3 @@
-#![feature(nll)]
-
 // Here is arielb1's basic example from rust-lang/rust#27282
 // that AST borrowck is flummoxed by:
 
diff --git a/src/test/ui/nll/match-guards-always-borrow.stderr b/src/test/ui/nll/match-guards-always-borrow.stderr
index 5b49db45a52ec..15f94043b430f 100644
--- a/src/test/ui/nll/match-guards-always-borrow.stderr
+++ b/src/test/ui/nll/match-guards-always-borrow.stderr
@@ -1,5 +1,5 @@
 error[E0507]: cannot move out of `foo` in pattern guard
-  --> $DIR/match-guards-always-borrow.rs:10:14
+  --> $DIR/match-guards-always-borrow.rs:8:14
    |
 LL |             (|| { let bar = foo; bar.take() })();
    |              ^^             ---
diff --git a/src/test/ui/nll/match-on-borrowed.rs b/src/test/ui/nll/match-on-borrowed.rs
index edce2b185df34..aba0a7f71f5c1 100644
--- a/src/test/ui/nll/match-on-borrowed.rs
+++ b/src/test/ui/nll/match-on-borrowed.rs
@@ -5,8 +5,6 @@
 // Test that we don't allow mutating the value being matched on in a way that
 // changes which patterns it matches, until we have chosen an arm.
 
-#![feature(nll)]
-
 struct A(i32, i32);
 
 fn struct_example(mut a: A) {
diff --git a/src/test/ui/nll/match-on-borrowed.stderr b/src/test/ui/nll/match-on-borrowed.stderr
index 284a910a01b8a..f9c9a84632212 100644
--- a/src/test/ui/nll/match-on-borrowed.stderr
+++ b/src/test/ui/nll/match-on-borrowed.stderr
@@ -1,5 +1,5 @@
 error[E0503]: cannot use `e` because it was mutably borrowed
-  --> $DIR/match-on-borrowed.rs:51:9
+  --> $DIR/match-on-borrowed.rs:49:9
    |
 LL |         E::V(ref mut x, _) => x,
    |              --------- borrow of `e.0` occurs here
@@ -11,7 +11,7 @@ LL |     x;
    |     - borrow later used here
 
 error[E0503]: cannot use `*f` because it was mutably borrowed
-  --> $DIR/match-on-borrowed.rs:64:9
+  --> $DIR/match-on-borrowed.rs:62:9
    |
 LL |         E::V(ref mut x, _) => x,
    |              --------- borrow of `f.0` occurs here
@@ -23,7 +23,7 @@ LL |     x;
    |     - borrow later used here
 
 error[E0503]: cannot use `t` because it was mutably borrowed
-  --> $DIR/match-on-borrowed.rs:82:9
+  --> $DIR/match-on-borrowed.rs:80:9
    |
 LL |     let x = &mut t;
    |             ------ borrow of `t` occurs here
@@ -35,7 +35,7 @@ LL |     x;
    |     - borrow later used here
 
 error[E0381]: use of possibly-uninitialized variable: `n`
-  --> $DIR/match-on-borrowed.rs:92:11
+  --> $DIR/match-on-borrowed.rs:90:11
    |
 LL |     match n {}
    |           ^ use of possibly-uninitialized `n`
diff --git a/src/test/ui/pattern/pattern-bindings-after-at.nll.stderr b/src/test/ui/pattern/pattern-bindings-after-at.nll.stderr
deleted file mode 100644
index 35ee7877f2f78..0000000000000
--- a/src/test/ui/pattern/pattern-bindings-after-at.nll.stderr
+++ /dev/null
@@ -1,22 +0,0 @@
-error[E0303]: pattern bindings are not allowed after an `@`
-  --> $DIR/pattern-bindings-after-at.rs:8:31
-   |
-LL |         ref mut z @ &mut Some(ref a) => {
-   |                               ^^^^^ not allowed after `@`
-
-error[E0502]: cannot borrow `_` as immutable because it is also borrowed as mutable
-  --> $DIR/pattern-bindings-after-at.rs:8:31
-   |
-LL |         ref mut z @ &mut Some(ref a) => {
-   |         ----------------------^^^^^-
-   |         |                     |
-   |         |                     immutable borrow occurs here
-   |         mutable borrow occurs here
-...
-LL |             **z = None;
-   |             ---------- mutable borrow later used here
-
-error: aborting due to 2 previous errors
-
-Some errors have detailed explanations: E0303, E0502.
-For more information about an error, try `rustc --explain E0303`.
diff --git a/src/test/ui/pattern/pattern-bindings-after-at.rs b/src/test/ui/pattern/pattern-bindings-after-at.rs
index 20a1d017cdd18..aff7264752de2 100644
--- a/src/test/ui/pattern/pattern-bindings-after-at.rs
+++ b/src/test/ui/pattern/pattern-bindings-after-at.rs
@@ -7,9 +7,7 @@ fn main() {
     match &mut Some(1) {
         ref mut z @ &mut Some(ref a) => {
         //~^ ERROR pattern bindings are not allowed after an `@`
-        //~| WARN cannot borrow `_` as immutable because it is also borrowed as mutable
-        //~| WARN this error has been downgraded to a warning for backwards compatibility
-        //~| WARN this represents potential undefined behavior in your code and this warning will
+        //~| ERROR cannot borrow `_` as immutable because it is also borrowed as mutable
             **z = None;
             println!("{}", *a);
         }
diff --git a/src/test/ui/pattern/pattern-bindings-after-at.stderr b/src/test/ui/pattern/pattern-bindings-after-at.stderr
index 70452a930ee70..35ee7877f2f78 100644
--- a/src/test/ui/pattern/pattern-bindings-after-at.stderr
+++ b/src/test/ui/pattern/pattern-bindings-after-at.stderr
@@ -4,7 +4,7 @@ error[E0303]: pattern bindings are not allowed after an `@`
 LL |         ref mut z @ &mut Some(ref a) => {
    |                               ^^^^^ not allowed after `@`
 
-warning[E0502]: cannot borrow `_` as immutable because it is also borrowed as mutable
+error[E0502]: cannot borrow `_` as immutable because it is also borrowed as mutable
   --> $DIR/pattern-bindings-after-at.rs:8:31
    |
 LL |         ref mut z @ &mut Some(ref a) => {
@@ -15,12 +15,8 @@ LL |         ref mut z @ &mut Some(ref a) => {
 ...
 LL |             **z = None;
    |             ---------- mutable borrow later used here
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
 
-error: aborting due to previous error
+error: aborting due to 2 previous errors
 
 Some errors have detailed explanations: E0303, E0502.
 For more information about an error, try `rustc --explain E0303`.
diff --git a/src/test/ui/thread-local-in-ctfe.nll.stderr b/src/test/ui/thread-local-in-ctfe.nll.stderr
deleted file mode 100644
index 18d01b1879018..0000000000000
--- a/src/test/ui/thread-local-in-ctfe.nll.stderr
+++ /dev/null
@@ -1,49 +0,0 @@
-error[E0625]: thread-local statics cannot be accessed at compile-time
-  --> $DIR/thread-local-in-ctfe.rs:6:17
-   |
-LL | static B: u32 = A;
-   |                 ^
-
-error[E0625]: thread-local statics cannot be accessed at compile-time
-  --> $DIR/thread-local-in-ctfe.rs:9:18
-   |
-LL | static C: &u32 = &A;
-   |                  ^^
-
-error[E0712]: thread-local variable borrowed past end of function
-  --> $DIR/thread-local-in-ctfe.rs:9:18
-   |
-LL | static C: &u32 = &A;
-   |                  ^^- end of enclosing function is here
-   |                  |
-   |                  thread-local variables cannot be borrowed beyond the end of the function
-
-error[E0625]: thread-local statics cannot be accessed at compile-time
-  --> $DIR/thread-local-in-ctfe.rs:15:16
-   |
-LL | const D: u32 = A;
-   |                ^
-
-error[E0625]: thread-local statics cannot be accessed at compile-time
-  --> $DIR/thread-local-in-ctfe.rs:18:17
-   |
-LL | const E: &u32 = &A;
-   |                 ^^
-
-error[E0712]: thread-local variable borrowed past end of function
-  --> $DIR/thread-local-in-ctfe.rs:18:17
-   |
-LL | const E: &u32 = &A;
-   |                 ^^- end of enclosing function is here
-   |                 |
-   |                 thread-local variables cannot be borrowed beyond the end of the function
-
-error[E0625]: thread-local statics cannot be accessed at compile-time
-  --> $DIR/thread-local-in-ctfe.rs:25:5
-   |
-LL |     A
-   |     ^
-
-error: aborting due to 7 previous errors
-
-For more information about this error, try `rustc --explain E0712`.
diff --git a/src/test/ui/thread-local-in-ctfe.rs b/src/test/ui/thread-local-in-ctfe.rs
index 7ca1a2e7e90c2..722c3883fdda4 100644
--- a/src/test/ui/thread-local-in-ctfe.rs
+++ b/src/test/ui/thread-local-in-ctfe.rs
@@ -8,18 +8,14 @@ static B: u32 = A;
 
 static C: &u32 = &A;
 //~^ ERROR thread-local statics cannot be accessed at compile-time
-//~| WARNING thread-local variable borrowed past end of function
-//~| WARNING this error has been downgraded to a warning
-//~| WARNING this warning will become a hard error in the future
+//~| ERROR thread-local variable borrowed past end of function
 
 const D: u32 = A;
 //~^ ERROR thread-local statics cannot be accessed at compile-time
 
 const E: &u32 = &A;
 //~^ ERROR thread-local statics cannot be accessed at compile-time
-//~| WARNING thread-local variable borrowed past end of function
-//~| WARNING this error has been downgraded to a warning
-//~| WARNING this warning will become a hard error in the future
+//~| ERROR thread-local variable borrowed past end of function
 
 const fn f() -> u32 {
     A
diff --git a/src/test/ui/thread-local-in-ctfe.stderr b/src/test/ui/thread-local-in-ctfe.stderr
index 6869109e67fc0..2983ac3f60cf2 100644
--- a/src/test/ui/thread-local-in-ctfe.stderr
+++ b/src/test/ui/thread-local-in-ctfe.stderr
@@ -10,48 +10,40 @@ error[E0625]: thread-local statics cannot be accessed at compile-time
 LL | static C: &u32 = &A;
    |                  ^^
 
-warning[E0712]: thread-local variable borrowed past end of function
+error[E0712]: thread-local variable borrowed past end of function
   --> $DIR/thread-local-in-ctfe.rs:9:18
    |
 LL | static C: &u32 = &A;
    |                  ^^- end of enclosing function is here
    |                  |
    |                  thread-local variables cannot be borrowed beyond the end of the function
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
 
 error[E0625]: thread-local statics cannot be accessed at compile-time
-  --> $DIR/thread-local-in-ctfe.rs:15:16
+  --> $DIR/thread-local-in-ctfe.rs:13:16
    |
 LL | const D: u32 = A;
    |                ^
 
 error[E0625]: thread-local statics cannot be accessed at compile-time
-  --> $DIR/thread-local-in-ctfe.rs:18:17
+  --> $DIR/thread-local-in-ctfe.rs:16:17
    |
 LL | const E: &u32 = &A;
    |                 ^^
 
-warning[E0712]: thread-local variable borrowed past end of function
-  --> $DIR/thread-local-in-ctfe.rs:18:17
+error[E0712]: thread-local variable borrowed past end of function
+  --> $DIR/thread-local-in-ctfe.rs:16:17
    |
 LL | const E: &u32 = &A;
    |                 ^^- end of enclosing function is here
    |                 |
    |                 thread-local variables cannot be borrowed beyond the end of the function
-   |
-   = warning: this error has been downgraded to a warning for backwards compatibility with previous releases
-   = warning: this represents potential undefined behavior in your code and this warning will become a hard error in the future
-   = note: for more information, try `rustc --explain E0729`
 
 error[E0625]: thread-local statics cannot be accessed at compile-time
-  --> $DIR/thread-local-in-ctfe.rs:25:5
+  --> $DIR/thread-local-in-ctfe.rs:21:5
    |
 LL |     A
    |     ^
 
-error: aborting due to 5 previous errors
+error: aborting due to 7 previous errors
 
 For more information about this error, try `rustc --explain E0712`.
diff --git a/src/test/ui/traits/reservation-impls/reservation-impl-coherence-conflict.rs b/src/test/ui/traits/reservation-impls/reservation-impl-coherence-conflict.rs
new file mode 100644
index 0000000000000..775278c30cd4c
--- /dev/null
+++ b/src/test/ui/traits/reservation-impls/reservation-impl-coherence-conflict.rs
@@ -0,0 +1,16 @@
+// compile-fail
+
+// check that reservation impls are accounted for in negative reasoning.
+
+#![feature(rustc_attrs)]
+
+trait MyTrait {}
+#[rustc_reservation_impl="this impl is reserved"]
+impl MyTrait for () {}
+
+trait OtherTrait {}
+impl OtherTrait for () {}
+impl<T: MyTrait> OtherTrait for T {}
+//~^ ERROR conflicting implementations
+
+fn main() {}
diff --git a/src/test/ui/traits/reservation-impls/reservation-impl-coherence-conflict.stderr b/src/test/ui/traits/reservation-impls/reservation-impl-coherence-conflict.stderr
new file mode 100644
index 0000000000000..47e141bd048eb
--- /dev/null
+++ b/src/test/ui/traits/reservation-impls/reservation-impl-coherence-conflict.stderr
@@ -0,0 +1,13 @@
+error[E0119]: conflicting implementations of trait `OtherTrait` for type `()`:
+  --> $DIR/reservation-impl-coherence-conflict.rs:13:1
+   |
+LL | impl OtherTrait for () {}
+   | ---------------------- first implementation here
+LL | impl<T: MyTrait> OtherTrait for T {}
+   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ conflicting implementation for `()`
+   |
+   = note: this impl is reserved
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0119`.
diff --git a/src/test/ui/traits/reservation-impls/reservation-impl-no-use.rs b/src/test/ui/traits/reservation-impls/reservation-impl-no-use.rs
new file mode 100644
index 0000000000000..3391daaabe975
--- /dev/null
+++ b/src/test/ui/traits/reservation-impls/reservation-impl-no-use.rs
@@ -0,0 +1,14 @@
+// compile-fail
+
+// check that reservation impls can't be used as normal impls in positive reasoning.
+
+#![feature(rustc_attrs)]
+
+trait MyTrait { fn foo(&self); }
+#[rustc_reservation_impl = "foo"]
+impl MyTrait for () { fn foo(&self) {} }
+
+fn main() {
+    <() as MyTrait>::foo(&());
+    //~^ ERROR the trait bound `(): MyTrait` is not satisfied
+}
diff --git a/src/test/ui/traits/reservation-impls/reservation-impl-no-use.stderr b/src/test/ui/traits/reservation-impls/reservation-impl-no-use.stderr
new file mode 100644
index 0000000000000..0cd56b978f10c
--- /dev/null
+++ b/src/test/ui/traits/reservation-impls/reservation-impl-no-use.stderr
@@ -0,0 +1,15 @@
+error[E0277]: the trait bound `(): MyTrait` is not satisfied
+  --> $DIR/reservation-impl-no-use.rs:12:26
+   |
+LL | trait MyTrait { fn foo(&self); }
+   |                 -------------- required by `MyTrait::foo`
+...
+LL |     <() as MyTrait>::foo(&());
+   |                          ^^^ the trait `MyTrait` is not implemented for `()`
+   |
+   = help: the following implementations were found:
+             <() as MyTrait>
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0277`.
diff --git a/src/test/ui/traits/reservation-impls/reservation-impl-non-lattice-ok.rs b/src/test/ui/traits/reservation-impls/reservation-impl-non-lattice-ok.rs
new file mode 100644
index 0000000000000..f14589ccf846d
--- /dev/null
+++ b/src/test/ui/traits/reservation-impls/reservation-impl-non-lattice-ok.rs
@@ -0,0 +1,59 @@
+// build-pass
+
+// Check that a reservation impl does not force other impls to follow
+// a lattice discipline.
+
+// Why did we ever want to do this?
+//
+// We want to eventually add a `impl<T> From<!> for T` impl. That impl conflicts
+// with existing impls - at least the `impl<T> From<T> for T` impl. There are
+// 2 ways we thought of for dealing with that conflict:
+//
+// 1. Using specialization and doing some handling for the
+// overlap. The current thought is to require ["intersection
+// impls"][ii], specialization", which means providing an
+// (higher-priority) impl for the intersection of every 2 conflicting
+// impls that determines what happens in the intersection case. That's
+// the first thing we thought about - see e.g.
+// https://github.com/rust-lang/rust/issues/57012#issuecomment-452150775
+//
+// 2. The other way is to notice that `impl From<!> for T` is basically a
+// marker trait since its only method is uninhabited, and allow for "marker
+// trait overlap", where the conflict "doesn't matter" because it can't
+// actually cause any ambiguity.
+//
+// Now it turned out lattice specialization doesn't work it, because an
+// `impl<T> From<T> for Smaht<T>` would require a `impl From<!> for Smaht<!>`,
+// breaking backwards-compatibility in a fairly painful way. So if we want to
+// go with a known approach, we should go with a "marker trait overlap"-style
+// approach.
+//
+// [ii]: http://smallcultfollowing.com/babysteps/blog/2016/09/24/intersection-impls/
+
+#![feature(rustc_attrs, never_type)]
+
+trait MyTrait {}
+
+impl MyTrait for ! {}
+
+trait MyFrom<T> {
+    fn my_from(x: T) -> Self;
+}
+
+// Given the "normal" impls for From
+#[rustc_reservation_impl="this impl is reserved"]
+impl<T> MyFrom<!> for T {
+    fn my_from(x: !) -> Self { match x {} }
+}
+
+impl<T> MyFrom<T> for T {
+    fn my_from(x: T) -> Self { x }
+}
+
+// ... we *do* want to allow this common pattern, of `From<!> for MySmaht<T>`
+struct MySmaht<T>(T);
+impl<T> MyFrom<T> for MySmaht<T> {
+    fn my_from(x: T) -> Self { MySmaht(x) }
+}
+
+fn main() {}
diff --git a/src/test/ui/traits/reservation-impls/reservation-impl-ok.rs b/src/test/ui/traits/reservation-impls/reservation-impl-ok.rs
new file mode 100644
index 0000000000000..611c8d8841323
--- /dev/null
+++ b/src/test/ui/traits/reservation-impls/reservation-impl-ok.rs
@@ -0,0 +1,28 @@
+// run-pass
+
+// rpass test for reservation impls. Not 100% required because `From` uses them,
+// but still.
+
+#![feature(rustc_attrs)]
+
+use std::mem;
+
+trait MyTrait<S> {
+    fn foo(&self, s: S) -> usize;
+}
+
+#[rustc_reservation_impl = "foo"]
+impl<T> MyTrait<u64> for T {
+    fn foo(&self, _x: u64) -> usize { 0 }
+}
+
+// reservation impls don't create coherence conflicts, even with
+// non-chain overlap.
+impl<S> MyTrait<S> for u32 {
+    fn foo(&self, _x: S) -> usize { mem::size_of::<S>() }
+}
+
+fn main() {
+    // ...and the non-reservation impl gets picked.XS
+    assert_eq!(0u32.foo(0u64), mem::size_of::<u64>());
+}