Split TypeVisitable from TypeFoldable

compiler/rustc_borrowck/src/constraint_generation.rs

@@ -5,8 +5,8 @@ use rustc_middle::mir::{
     BasicBlock, BasicBlockData, Body, Local, Location, Place, PlaceRef, ProjectionElem, Rvalue,
     SourceInfo, Statement, StatementKind, Terminator, TerminatorKind, UserTypeProjection,
 };
-use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::subst::SubstsRef;
+use rustc_middle::ty::visit::TypeVisitable;
 use rustc_middle::ty::{self, RegionVid, Ty};
 
 use crate::{
@@ -163,7 +163,7 @@ impl<'cx, 'cg, 'tcx> ConstraintGeneration<'cx, 'cg, 'tcx> {
     /// `location`.
     fn add_regular_live_constraint<T>(&mut self, live_ty: T, location: Location)
     where
-        T: TypeFoldable<'tcx>,
+        T: TypeVisitable<'tcx>,
     {
         debug!("add_regular_live_constraint(live_ty={:?}, location={:?})", live_ty, location);
 

compiler/rustc_borrowck/src/region_infer/mod.rs

@@ -19,7 +19,9 @@ use rustc_middle::mir::{
 };
 use rustc_middle::traits::ObligationCause;
 use rustc_middle::traits::ObligationCauseCode;
-use rustc_middle::ty::{self, subst::SubstsRef, RegionVid, Ty, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{
+    self, subst::SubstsRef, RegionVid, Ty, TyCtxt, TypeFoldable, TypeVisitable,
+};
 use rustc_span::Span;
 
 use crate::{

compiler/rustc_borrowck/src/region_infer/opaque_types.rs

@@ -2,7 +2,9 @@ use rustc_data_structures::vec_map::VecMap;
 use rustc_hir::def_id::DefId;
 use rustc_hir::OpaqueTyOrigin;
 use rustc_infer::infer::InferCtxt;
-use rustc_middle::ty::{self, OpaqueHiddenType, OpaqueTypeKey, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{
+    self, OpaqueHiddenType, OpaqueTypeKey, TyCtxt, TypeFoldable, TypeVisitable,
+};
 use rustc_trait_selection::opaque_types::InferCtxtExt;
 
 use super::RegionInferenceContext;

compiler/rustc_borrowck/src/type_check/constraint_conversion.rs

@@ -6,7 +6,7 @@ use rustc_infer::infer::region_constraints::{GenericKind, VerifyBound};
 use rustc_infer::infer::{self, InferCtxt, SubregionOrigin};
 use rustc_middle::mir::ConstraintCategory;
 use rustc_middle::ty::subst::GenericArgKind;
-use rustc_middle::ty::TypeFoldable;
+use rustc_middle::ty::TypeVisitable;
 use rustc_middle::ty::{self, TyCtxt};
 use rustc_span::{Span, DUMMY_SP};
 

compiler/rustc_borrowck/src/type_check/liveness/trace.rs

@@ -3,7 +3,7 @@ use rustc_index::bit_set::HybridBitSet;
 use rustc_index::interval::IntervalSet;
 use rustc_infer::infer::canonical::QueryRegionConstraints;
 use rustc_middle::mir::{BasicBlock, Body, ConstraintCategory, Local, Location};
-use rustc_middle::ty::{Ty, TypeFoldable};
+use rustc_middle::ty::{Ty, TypeVisitable};
 use rustc_trait_selection::traits::query::dropck_outlives::DropckOutlivesResult;
 use rustc_trait_selection::traits::query::type_op::outlives::DropckOutlives;
 use rustc_trait_selection::traits::query::type_op::{TypeOp, TypeOpOutput};
@@ -477,7 +477,7 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
     /// points `live_at`.
     fn add_use_live_facts_for(
         &mut self,
-        value: impl TypeFoldable<'tcx>,
+        value: impl TypeVisitable<'tcx>,
         live_at: &IntervalSet<PointIndex>,
     ) {
         debug!("add_use_live_facts_for(value={:?})", value);
@@ -542,7 +542,7 @@ impl<'tcx> LivenessContext<'_, '_, '_, 'tcx> {
     fn make_all_regions_live(
         elements: &RegionValueElements,
         typeck: &mut TypeChecker<'_, 'tcx>,
-        value: impl TypeFoldable<'tcx>,
+        value: impl TypeVisitable<'tcx>,
         live_at: &IntervalSet<PointIndex>,
     ) {
         debug!("make_all_regions_live(value={:?})", value);

compiler/rustc_borrowck/src/type_check/mod.rs

@@ -27,8 +27,8 @@ use rustc_middle::mir::AssertKind;
 use rustc_middle::mir::*;
 use rustc_middle::ty::adjustment::PointerCast;
 use rustc_middle::ty::cast::CastTy;
-use rustc_middle::ty::fold::TypeFoldable;
 use rustc_middle::ty::subst::{GenericArgKind, SubstsRef, UserSubsts};
+use rustc_middle::ty::visit::TypeVisitable;
 use rustc_middle::ty::{
     self, CanonicalUserTypeAnnotation, CanonicalUserTypeAnnotations, OpaqueHiddenType,
     OpaqueTypeKey, RegionVid, ToPredicate, Ty, TyCtxt, UserType, UserTypeAnnotationIndex,

compiler/rustc_codegen_cranelift/src/lib.rs

@@ -79,7 +79,7 @@ mod prelude {
     pub(crate) use rustc_middle::ty::layout::{self, LayoutOf, TyAndLayout};
     pub(crate) use rustc_middle::ty::{
         self, FloatTy, Instance, InstanceDef, IntTy, ParamEnv, Ty, TyCtxt, TypeAndMut,
-        TypeFoldable, UintTy,
+        TypeFoldable, TypeVisitable, UintTy,
     };
     pub(crate) use rustc_target::abi::{Abi, Scalar, Size, VariantIdx};
 

compiler/rustc_codegen_gcc/src/callee.rs

@@ -1,6 +1,6 @@
 use gccjit::{FunctionType, RValue};
 use rustc_codegen_ssa::traits::BaseTypeMethods;
-use rustc_middle::ty::{self, Instance, TypeFoldable};
+use rustc_middle::ty::{self, Instance, TypeVisitable};
 use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt};
 
 use crate::abi::FnAbiGccExt;

compiler/rustc_codegen_gcc/src/mono_item.rs

@@ -1,7 +1,7 @@
 use rustc_codegen_ssa::traits::PreDefineMethods;
 use rustc_middle::middle::codegen_fn_attrs::CodegenFnAttrFlags;
 use rustc_middle::mir::mono::{Linkage, Visibility};
-use rustc_middle::ty::{self, Instance, TypeFoldable};
+use rustc_middle::ty::{self, Instance, TypeVisitable};
 use rustc_middle::ty::layout::{FnAbiOf, LayoutOf};
 use rustc_span::def_id::DefId;
 

compiler/rustc_codegen_gcc/src/type_of.rs

@@ -3,7 +3,7 @@ use std::fmt::Write;
 use gccjit::{Struct, Type};
 use crate::rustc_codegen_ssa::traits::{BaseTypeMethods, DerivedTypeMethods, LayoutTypeMethods};
 use rustc_middle::bug;
-use rustc_middle::ty::{self, Ty, TypeFoldable};
+use rustc_middle::ty::{self, Ty, TypeVisitable};
 use rustc_middle::ty::layout::{FnAbiOf, LayoutOf, TyAndLayout};
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_target::abi::{self, Abi, F32, F64, FieldsShape, Int, Integer, Pointer, PointeeInfo, Size, TyAbiInterface, Variants};

compiler/rustc_codegen_llvm/src/callee.rs

@@ -13,7 +13,7 @@ use rustc_codegen_ssa::traits::*;
 use tracing::debug;
 
 use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt};
-use rustc_middle::ty::{self, Instance, TypeFoldable};
+use rustc_middle::ty::{self, Instance, TypeVisitable};
 
 /// Codegens a reference to a fn/method item, monomorphizing and
 /// inlining as it goes.

compiler/rustc_codegen_llvm/src/debuginfo/mod.rs

@@ -27,7 +27,7 @@ use rustc_index::vec::IndexVec;
 use rustc_middle::mir;
 use rustc_middle::ty::layout::LayoutOf;
 use rustc_middle::ty::subst::{GenericArgKind, SubstsRef};
-use rustc_middle::ty::{self, Instance, ParamEnv, Ty, TypeFoldable};
+use rustc_middle::ty::{self, Instance, ParamEnv, Ty, TypeVisitable};
 use rustc_session::config::{self, DebugInfo};
 use rustc_session::Session;
 use rustc_span::symbol::Symbol;

compiler/rustc_codegen_llvm/src/mono_item.rs

@@ -8,7 +8,7 @@ use rustc_hir::def_id::{DefId, LOCAL_CRATE};
 pub use rustc_middle::mir::mono::MonoItem;
 use rustc_middle::mir::mono::{Linkage, Visibility};
 use rustc_middle::ty::layout::{FnAbiOf, LayoutOf};
-use rustc_middle::ty::{self, Instance, TypeFoldable};
+use rustc_middle::ty::{self, Instance, TypeVisitable};
 use rustc_session::config::CrateType;
 use rustc_target::spec::RelocModel;
 use tracing::debug;

compiler/rustc_codegen_llvm/src/type_of.rs

@@ -6,7 +6,7 @@ use rustc_codegen_ssa::traits::*;
 use rustc_middle::bug;
 use rustc_middle::ty::layout::{FnAbiOf, LayoutOf, TyAndLayout};
 use rustc_middle::ty::print::{with_no_trimmed_paths, with_no_visible_paths};
-use rustc_middle::ty::{self, Ty, TypeFoldable};
+use rustc_middle::ty::{self, Ty, TypeVisitable};
 use rustc_target::abi::{Abi, AddressSpace, Align, FieldsShape};
 use rustc_target::abi::{Int, Pointer, F32, F64};
 use rustc_target::abi::{PointeeInfo, Scalar, Size, TyAbiInterface, Variants};

compiler/rustc_codegen_ssa/src/mir/block.rs

@@ -17,7 +17,7 @@ use rustc_middle::mir::AssertKind;
 use rustc_middle::mir::{self, SwitchTargets};
 use rustc_middle::ty::layout::{HasTyCtxt, LayoutOf};
 use rustc_middle::ty::print::{with_no_trimmed_paths, with_no_visible_paths};
-use rustc_middle::ty::{self, Instance, Ty, TypeFoldable};
+use rustc_middle::ty::{self, Instance, Ty, TypeVisitable};
 use rustc_span::source_map::Span;
 use rustc_span::{sym, Symbol};
 use rustc_symbol_mangling::typeid_for_fnabi;

compiler/rustc_codegen_ssa/src/mir/mod.rs

@@ -2,7 +2,7 @@ use crate::traits::*;
 use rustc_middle::mir;
 use rustc_middle::mir::interpret::ErrorHandled;
 use rustc_middle::ty::layout::{FnAbiOf, HasTyCtxt, TyAndLayout};
-use rustc_middle::ty::{self, Instance, Ty, TypeFoldable};
+use rustc_middle::ty::{self, Instance, Ty, TypeFoldable, TypeVisitable};
 use rustc_symbol_mangling::typeid_for_fnabi;
 use rustc_target::abi::call::{FnAbi, PassMode};
 

compiler/rustc_const_eval/src/interpret/util.rs

@@ -1,5 +1,5 @@
 use rustc_middle::mir::interpret::InterpResult;
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeSuperFoldable, TypeVisitor};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeSuperVisitable, TypeVisitable, TypeVisitor};
 use std::convert::TryInto;
 use std::ops::ControlFlow;
 
@@ -10,7 +10,7 @@ use std::ops::ControlFlow;
 /// case these parameters are unused.
 pub(crate) fn ensure_monomorphic_enough<'tcx, T>(tcx: TyCtxt<'tcx>, ty: T) -> InterpResult<'tcx>
 where
-    T: TypeFoldable<'tcx>,
+    T: TypeVisitable<'tcx>,
 {
     debug!("ensure_monomorphic_enough: ty={:?}", ty);
     if !ty.needs_subst() {

compiler/rustc_const_eval/src/transform/check_consts/check.rs

@@ -10,7 +10,7 @@ use rustc_middle::mir::visit::{MutatingUseContext, NonMutatingUseContext, PlaceC
 use rustc_middle::mir::*;
 use rustc_middle::ty::subst::{GenericArgKind, InternalSubsts};
 use rustc_middle::ty::{self, adjustment::PointerCast, Instance, InstanceDef, Ty, TyCtxt};
-use rustc_middle::ty::{Binder, TraitPredicate, TraitRef, TypeFoldable};
+use rustc_middle::ty::{Binder, TraitPredicate, TraitRef, TypeVisitable};
 use rustc_mir_dataflow::{self, Analysis};
 use rustc_span::{sym, Span, Symbol};
 use rustc_trait_selection::traits::error_reporting::InferCtxtExt;

compiler/rustc_const_eval/src/transform/promote_consts.rs

@@ -17,7 +17,7 @@ use rustc_middle::mir::traversal::ReversePostorderIter;
 use rustc_middle::mir::visit::{MutVisitor, MutatingUseContext, PlaceContext, Visitor};
 use rustc_middle::mir::*;
 use rustc_middle::ty::subst::InternalSubsts;
-use rustc_middle::ty::{self, List, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{self, List, TyCtxt, TypeVisitable};
 use rustc_span::Span;
 
 use rustc_index::vec::{Idx, IndexVec};

compiler/rustc_const_eval/src/transform/validate.rs

@@ -12,7 +12,7 @@ use rustc_middle::mir::{
     Statement, StatementKind, Terminator, TerminatorKind, UnOp, START_BLOCK,
 };
 use rustc_middle::ty::fold::BottomUpFolder;
-use rustc_middle::ty::{self, InstanceDef, ParamEnv, Ty, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{self, InstanceDef, ParamEnv, Ty, TyCtxt, TypeFoldable, TypeVisitable};
 use rustc_mir_dataflow::impls::MaybeStorageLive;
 use rustc_mir_dataflow::storage::always_live_locals;
 use rustc_mir_dataflow::{Analysis, ResultsCursor};

compiler/rustc_infer/src/infer/combine.rs

@@ -37,7 +37,7 @@ use rustc_middle::traits::ObligationCause;
 use rustc_middle::ty::error::{ExpectedFound, TypeError};
 use rustc_middle::ty::relate::{self, Relate, RelateResult, TypeRelation};
 use rustc_middle::ty::subst::SubstsRef;
-use rustc_middle::ty::{self, InferConst, ToPredicate, Ty, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{self, InferConst, ToPredicate, Ty, TyCtxt, TypeVisitable};
 use rustc_middle::ty::{IntType, UintType};
 use rustc_span::{Span, DUMMY_SP};
 

compiler/rustc_infer/src/infer/error_reporting/mod.rs

@@ -68,7 +68,7 @@ use rustc_middle::dep_graph::DepContext;
 use rustc_middle::ty::print::with_no_trimmed_paths;
 use rustc_middle::ty::{
     self, error::TypeError, Binder, List, Region, Subst, Ty, TyCtxt, TypeFoldable,
-    TypeSuperFoldable,
+    TypeSuperVisitable, TypeVisitable,
 };
 use rustc_span::{sym, symbol::kw, BytePos, DesugaringKind, Pos, Span};
 use rustc_target::spec::abi;
@@ -1540,7 +1540,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
             }
         }
 
-        impl<'tcx> ty::fold::TypeVisitor<'tcx> for OpaqueTypesVisitor<'tcx> {
+        impl<'tcx> ty::visit::TypeVisitor<'tcx> for OpaqueTypesVisitor<'tcx> {
             fn visit_ty(&mut self, t: Ty<'tcx>) -> ControlFlow<Self::BreakTy> {
                 if let Some((kind, def_id)) = TyCategory::from_ty(self.tcx, t) {
                     let span = self.tcx.def_span(def_id);

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/static_impl_trait.rs

@@ -10,7 +10,7 @@ use rustc_hir::def_id::DefId;
 use rustc_hir::intravisit::{walk_ty, Visitor};
 use rustc_hir::{self as hir, GenericBound, Item, ItemKind, Lifetime, LifetimeName, Node, TyKind};
 use rustc_middle::ty::{
-    self, AssocItemContainer, StaticLifetimeVisitor, Ty, TyCtxt, TypeSuperFoldable, TypeVisitor,
+    self, AssocItemContainer, StaticLifetimeVisitor, Ty, TyCtxt, TypeSuperVisitable, TypeVisitor,
 };
 use rustc_span::symbol::Ident;
 use rustc_span::Span;

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/trait_impl_difference.rs

@@ -11,7 +11,7 @@ use rustc_hir::def_id::{DefId, LocalDefId};
 use rustc_hir::intravisit::Visitor;
 use rustc_middle::hir::nested_filter;
 use rustc_middle::ty::print::RegionHighlightMode;
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeSuperFoldable, TypeVisitor};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeSuperVisitable, TypeVisitor};
 use rustc_span::{Span, Symbol};
 
 use std::ops::ControlFlow;
@@ -88,7 +88,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
             }
         }
 
-        impl<'tcx> ty::fold::TypeVisitor<'tcx> for HighlightBuilder<'tcx> {
+        impl<'tcx> ty::visit::TypeVisitor<'tcx> for HighlightBuilder<'tcx> {
             fn visit_region(&mut self, r: ty::Region<'tcx>) -> ControlFlow<Self::BreakTy> {
                 if !r.has_name() && self.counter <= 3 {
                     self.highlight.highlighting_region(r, self.counter);

compiler/rustc_infer/src/infer/error_reporting/nice_region_error/util.rs

@@ -5,7 +5,7 @@ use crate::infer::error_reporting::nice_region_error::NiceRegionError;
 use crate::infer::TyCtxt;
 use rustc_hir as hir;
 use rustc_hir::def_id::LocalDefId;
-use rustc_middle::ty::{self, Binder, DefIdTree, Region, Ty, TypeFoldable};
+use rustc_middle::ty::{self, Binder, DefIdTree, Region, Ty, TypeVisitable};
 use rustc_span::Span;
 
 /// Information about the anonymous region we are searching for.
@@ -142,7 +142,7 @@ impl<'a, 'tcx> NiceRegionError<'a, 'tcx> {
 
     fn includes_region(
         &self,
-        ty: Binder<'tcx, impl TypeFoldable<'tcx>>,
+        ty: Binder<'tcx, impl TypeVisitable<'tcx>>,
         region: ty::BoundRegionKind,
     ) -> bool {
         let late_bound_regions = self.tcx().collect_referenced_late_bound_regions(&ty);

compiler/rustc_infer/src/infer/freshen.rs

@@ -34,7 +34,7 @@ use super::InferCtxt;
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::infer::unify_key::ToType;
 use rustc_middle::ty::fold::TypeFolder;
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeSuperFoldable};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable, TypeSuperFoldable, TypeVisitable};
 use std::collections::hash_map::Entry;
 
 pub struct TypeFreshener<'a, 'tcx> {

compiler/rustc_infer/src/infer/mod.rs

@@ -25,6 +25,7 @@ use rustc_middle::ty::error::{ExpectedFound, TypeError};
 use rustc_middle::ty::fold::{TypeFoldable, TypeFolder, TypeSuperFoldable};
 use rustc_middle::ty::relate::RelateResult;
 use rustc_middle::ty::subst::{GenericArg, GenericArgKind, InternalSubsts, SubstsRef};
+use rustc_middle::ty::visit::TypeVisitable;
 pub use rustc_middle::ty::IntVarValue;
 use rustc_middle::ty::{self, GenericParamDefKind, InferConst, Ty, TyCtxt};
 use rustc_middle::ty::{ConstVid, FloatVid, IntVid, TyVid};
@@ -318,7 +319,7 @@ pub struct InferCtxt<'a, 'tcx> {
 }
 
 /// See the `error_reporting` module for more details.
-#[derive(Clone, Copy, Debug, PartialEq, Eq, TypeFoldable)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq, TypeFoldable, TypeVisitable)]
 pub enum ValuePairs<'tcx> {
     Regions(ExpectedFound<ty::Region<'tcx>>),
     Terms(ExpectedFound<ty::Term<'tcx>>),
@@ -1438,7 +1439,7 @@ impl<'a, 'tcx> InferCtxt<'a, 'tcx> {
     /// `resolve_vars_if_possible()`.
     pub fn unresolved_type_vars<T>(&self, value: &T) -> Option<(Ty<'tcx>, Option<Span>)>
     where
-        T: TypeFoldable<'tcx>,
+        T: TypeVisitable<'tcx>,
     {
         value.visit_with(&mut resolve::UnresolvedTypeFinder::new(self)).break_value()
     }

compiler/rustc_infer/src/infer/nll_relate/mod.rs

@@ -27,8 +27,8 @@ use crate::infer::{ConstVarValue, ConstVariableValue};
 use crate::infer::{TypeVariableOrigin, TypeVariableOriginKind};
 use rustc_data_structures::fx::FxHashMap;
 use rustc_middle::ty::error::TypeError;
-use rustc_middle::ty::fold::{TypeFoldable, TypeSuperFoldable, TypeVisitor};
 use rustc_middle::ty::relate::{self, Relate, RelateResult, TypeRelation};
+use rustc_middle::ty::visit::{TypeSuperVisitable, TypeVisitable, TypeVisitor};
 use rustc_middle::ty::{self, InferConst, Ty, TyCtxt};
 use rustc_span::Span;
 use std::fmt::Debug;
@@ -810,7 +810,7 @@ struct ScopeInstantiator<'me, 'tcx> {
 }
 
 impl<'me, 'tcx> TypeVisitor<'tcx> for ScopeInstantiator<'me, 'tcx> {
-    fn visit_binder<T: TypeFoldable<'tcx>>(
+    fn visit_binder<T: TypeVisitable<'tcx>>(
         &mut self,
         t: &ty::Binder<'tcx, T>,
     ) -> ControlFlow<Self::BreakTy> {

compiler/rustc_infer/src/infer/opaque_types.rs

@@ -9,7 +9,8 @@ use rustc_middle::traits::ObligationCause;
 use rustc_middle::ty::fold::BottomUpFolder;
 use rustc_middle::ty::subst::{GenericArgKind, Subst};
 use rustc_middle::ty::{
-    self, OpaqueHiddenType, OpaqueTypeKey, Ty, TyCtxt, TypeFoldable, TypeSuperFoldable, TypeVisitor,
+    self, OpaqueHiddenType, OpaqueTypeKey, Ty, TyCtxt, TypeFoldable, TypeSuperVisitable,
+    TypeVisitable, TypeVisitor,
 };
 use rustc_span::Span;
 
@@ -461,7 +462,7 @@ impl<'tcx, OP> TypeVisitor<'tcx> for ConstrainOpaqueTypeRegionVisitor<OP>
 where
     OP: FnMut(ty::Region<'tcx>),
 {
-    fn visit_binder<T: TypeFoldable<'tcx>>(
+    fn visit_binder<T: TypeVisitable<'tcx>>(
         &mut self,
         t: &ty::Binder<'tcx, T>,
     ) -> ControlFlow<Self::BreakTy> {

compiler/rustc_infer/src/infer/outlives/components.rs

@@ -4,7 +4,7 @@
 
 use rustc_data_structures::sso::SsoHashSet;
 use rustc_middle::ty::subst::{GenericArg, GenericArgKind};
-use rustc_middle::ty::{self, Ty, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{self, Ty, TyCtxt, TypeVisitable};
 use smallvec::{smallvec, SmallVec};
 
 #[derive(Debug)]

compiler/rustc_infer/src/infer/outlives/obligations.rs

@@ -69,7 +69,7 @@ use crate::infer::{
 use crate::traits::{ObligationCause, ObligationCauseCode};
 use rustc_data_structures::undo_log::UndoLogs;
 use rustc_middle::ty::subst::GenericArgKind;
-use rustc_middle::ty::{self, Region, Ty, TyCtxt, TypeFoldable};
+use rustc_middle::ty::{self, Region, Ty, TyCtxt, TypeVisitable};
 use smallvec::smallvec;
 
 impl<'cx, 'tcx> InferCtxt<'cx, 'tcx> {

compiler/rustc_infer/src/infer/outlives/test_type_match.rs

@@ -1,7 +1,7 @@
 use std::collections::hash_map::Entry;
 
 use rustc_data_structures::fx::FxHashMap;
-use rustc_middle::ty::TypeFoldable;
+use rustc_middle::ty::TypeVisitable;
 use rustc_middle::ty::{
     self,
     error::TypeError,