Rollup merge of #130294 - nnethercote:more-lifetimes, r=lcnr

Lifetime cleanups

The last commit is very opinionated, let's see how we go.

r? `@oli-obk`

compiler/rustc_arena/src/lib.rs

@@ -614,34 +614,34 @@ pub macro declare_arena([$($a:tt $name:ident: $ty:ty,)*]) {
 
     pub trait ArenaAllocatable<'tcx, C = rustc_arena::IsNotCopy>: Sized {
         #[allow(clippy::mut_from_ref)]
-        fn allocate_on<'a>(self, arena: &'a Arena<'tcx>) -> &'a mut Self;
+        fn allocate_on(self, arena: &'tcx Arena<'tcx>) -> &'tcx mut Self;
         #[allow(clippy::mut_from_ref)]
-        fn allocate_from_iter<'a>(
+        fn allocate_from_iter(
-            arena: &'a Arena<'tcx>,
+            arena: &'tcx Arena<'tcx>,
             iter: impl ::std::iter::IntoIterator<Item = Self>,
-        ) -> &'a mut [Self];
+        ) -> &'tcx mut [Self];
     }
 
     // Any type that impls `Copy` can be arena-allocated in the `DroplessArena`.
     impl<'tcx, T: Copy> ArenaAllocatable<'tcx, rustc_arena::IsCopy> for T {
         #[inline]
         #[allow(clippy::mut_from_ref)]
-        fn allocate_on<'a>(self, arena: &'a Arena<'tcx>) -> &'a mut Self {
+        fn allocate_on(self, arena: &'tcx Arena<'tcx>) -> &'tcx mut Self {
             arena.dropless.alloc(self)
         }
         #[inline]
         #[allow(clippy::mut_from_ref)]
-        fn allocate_from_iter<'a>(
+        fn allocate_from_iter(
-            arena: &'a Arena<'tcx>,
+            arena: &'tcx Arena<'tcx>,
             iter: impl ::std::iter::IntoIterator<Item = Self>,
-        ) -> &'a mut [Self] {
+        ) -> &'tcx mut [Self] {
             arena.dropless.alloc_from_iter(iter)
         }
     }
     $(
         impl<'tcx> ArenaAllocatable<'tcx, rustc_arena::IsNotCopy> for $ty {
             #[inline]
-            fn allocate_on<'a>(self, arena: &'a Arena<'tcx>) -> &'a mut Self {
+            fn allocate_on(self, arena: &'tcx Arena<'tcx>) -> &'tcx mut Self {
                 if !::std::mem::needs_drop::<Self>() {
                     arena.dropless.alloc(self)
                 } else {
@@ -651,10 +651,10 @@ pub macro declare_arena([$($a:tt $name:ident: $ty:ty,)*]) {
 
             #[inline]
             #[allow(clippy::mut_from_ref)]
-            fn allocate_from_iter<'a>(
+            fn allocate_from_iter(
-                arena: &'a Arena<'tcx>,
+                arena: &'tcx Arena<'tcx>,
                 iter: impl ::std::iter::IntoIterator<Item = Self>,
-            ) -> &'a mut [Self] {
+            ) -> &'tcx mut [Self] {
                 if !::std::mem::needs_drop::<Self>() {
                     arena.dropless.alloc_from_iter(iter)
                 } else {
@@ -667,7 +667,7 @@ pub macro declare_arena([$($a:tt $name:ident: $ty:ty,)*]) {
     impl<'tcx> Arena<'tcx> {
         #[inline]
         #[allow(clippy::mut_from_ref)]
-        pub fn alloc<T: ArenaAllocatable<'tcx, C>, C>(&self, value: T) -> &mut T {
+        pub fn alloc<T: ArenaAllocatable<'tcx, C>, C>(&'tcx self, value: T) -> &mut T {
             value.allocate_on(self)
         }
 
@@ -691,7 +691,7 @@ pub macro declare_arena([$($a:tt $name:ident: $ty:ty,)*]) {
 
         #[allow(clippy::mut_from_ref)]
         pub fn alloc_from_iter<T: ArenaAllocatable<'tcx, C>, C>(
-            &self,
+            &'tcx self,
             iter: impl ::std::iter::IntoIterator<Item = T>,
         ) -> &mut [T] {
             T::allocate_from_iter(self, iter)

compiler/rustc_borrowck/src/constraints/graph.rs

@@ -97,11 +97,11 @@ impl<D: ConstraintGraphDirection> ConstraintGraph<D> {
     /// Given the constraint set from which this graph was built
     /// creates a region graph so that you can iterate over *regions*
     /// and not constraints.
-    pub(crate) fn region_graph<'rg, 'tcx>(
+    pub(crate) fn region_graph<'a, 'tcx>(
-        &'rg self,
+        &'a self,
-        set: &'rg OutlivesConstraintSet<'tcx>,
+        set: &'a OutlivesConstraintSet<'tcx>,
         static_region: RegionVid,
-    ) -> RegionGraph<'rg, 'tcx, D> {
+    ) -> RegionGraph<'a, 'tcx, D> {
         RegionGraph::new(set, self, static_region)
     }
 
@@ -130,15 +130,15 @@ impl<D: ConstraintGraphDirection> ConstraintGraph<D> {
     }
 }
 
-pub(crate) struct Edges<'s, 'tcx, D: ConstraintGraphDirection> {
+pub(crate) struct Edges<'a, 'tcx, D: ConstraintGraphDirection> {
-    graph: &'s ConstraintGraph<D>,
+    graph: &'a ConstraintGraph<D>,
-    constraints: &'s OutlivesConstraintSet<'tcx>,
+    constraints: &'a OutlivesConstraintSet<'tcx>,
     pointer: Option<OutlivesConstraintIndex>,
     next_static_idx: Option<usize>,
     static_region: RegionVid,
 }
 
-impl<'s, 'tcx, D: ConstraintGraphDirection> Iterator for Edges<'s, 'tcx, D> {
+impl<'a, 'tcx, D: ConstraintGraphDirection> Iterator for Edges<'a, 'tcx, D> {
     type Item = OutlivesConstraint<'tcx>;
 
     fn next(&mut self) -> Option<Self::Item> {
@@ -171,20 +171,20 @@ impl<'s, 'tcx, D: ConstraintGraphDirection> Iterator for Edges<'s, 'tcx, D> {
 /// This struct brings together a constraint set and a (normal, not
 /// reverse) constraint graph. It implements the graph traits and is
 /// usd for doing the SCC computation.
-pub(crate) struct RegionGraph<'s, 'tcx, D: ConstraintGraphDirection> {
+pub(crate) struct RegionGraph<'a, 'tcx, D: ConstraintGraphDirection> {
-    set: &'s OutlivesConstraintSet<'tcx>,
+    set: &'a OutlivesConstraintSet<'tcx>,
-    constraint_graph: &'s ConstraintGraph<D>,
+    constraint_graph: &'a ConstraintGraph<D>,
     static_region: RegionVid,
 }
 
-impl<'s, 'tcx, D: ConstraintGraphDirection> RegionGraph<'s, 'tcx, D> {
+impl<'a, 'tcx, D: ConstraintGraphDirection> RegionGraph<'a, 'tcx, D> {
     /// Creates a "dependency graph" where each region constraint `R1:
     /// R2` is treated as an edge `R1 -> R2`. We use this graph to
     /// construct SCCs for region inference but also for error
     /// reporting.
     pub(crate) fn new(
-        set: &'s OutlivesConstraintSet<'tcx>,
+        set: &'a OutlivesConstraintSet<'tcx>,
-        constraint_graph: &'s ConstraintGraph<D>,
+        constraint_graph: &'a ConstraintGraph<D>,
         static_region: RegionVid,
     ) -> Self {
         Self { set, constraint_graph, static_region }
@@ -192,18 +192,18 @@ impl<'s, 'tcx, D: ConstraintGraphDirection> RegionGraph<'s, 'tcx, D> {
 
     /// Given a region `R`, iterate over all regions `R1` such that
     /// there exists a constraint `R: R1`.
-    pub(crate) fn outgoing_regions(&self, region_sup: RegionVid) -> Successors<'s, 'tcx, D> {
+    pub(crate) fn outgoing_regions(&self, region_sup: RegionVid) -> Successors<'a, 'tcx, D> {
         Successors {
             edges: self.constraint_graph.outgoing_edges(region_sup, self.set, self.static_region),
         }
     }
 }
 
-pub(crate) struct Successors<'s, 'tcx, D: ConstraintGraphDirection> {
+pub(crate) struct Successors<'a, 'tcx, D: ConstraintGraphDirection> {
-    edges: Edges<'s, 'tcx, D>,
+    edges: Edges<'a, 'tcx, D>,
 }
 
-impl<'s, 'tcx, D: ConstraintGraphDirection> Iterator for Successors<'s, 'tcx, D> {
+impl<'a, 'tcx, D: ConstraintGraphDirection> Iterator for Successors<'a, 'tcx, D> {
     type Item = RegionVid;
 
     fn next(&mut self) -> Option<Self::Item> {
@@ -211,7 +211,7 @@ impl<'s, 'tcx, D: ConstraintGraphDirection> Iterator for Successors<'s, 'tcx, D>
     }
 }
 
-impl<'s, 'tcx, D: ConstraintGraphDirection> graph::DirectedGraph for RegionGraph<'s, 'tcx, D> {
+impl<'a, 'tcx, D: ConstraintGraphDirection> graph::DirectedGraph for RegionGraph<'a, 'tcx, D> {
     type Node = RegionVid;
 
     fn num_nodes(&self) -> usize {
@@ -219,7 +219,7 @@ impl<'s, 'tcx, D: ConstraintGraphDirection> graph::DirectedGraph for RegionGraph
     }
 }
 
-impl<'s, 'tcx, D: ConstraintGraphDirection> graph::Successors for RegionGraph<'s, 'tcx, D> {
+impl<'a, 'tcx, D: ConstraintGraphDirection> graph::Successors for RegionGraph<'a, 'tcx, D> {
     fn successors(&self, node: Self::Node) -> impl Iterator<Item = Self::Node> {
         self.outgoing_regions(node)
     }

compiler/rustc_borrowck/src/dataflow.rs

@@ -112,16 +112,16 @@ pub struct Borrows<'a, 'tcx> {
     borrows_out_of_scope_at_location: FxIndexMap<Location, Vec<BorrowIndex>>,
 }
 
-struct OutOfScopePrecomputer<'mir, 'tcx> {
+struct OutOfScopePrecomputer<'a, 'tcx> {
     visited: BitSet<mir::BasicBlock>,
     visit_stack: Vec<mir::BasicBlock>,
-    body: &'mir Body<'tcx>,
+    body: &'a Body<'tcx>,
-    regioncx: &'mir RegionInferenceContext<'tcx>,
+    regioncx: &'a RegionInferenceContext<'tcx>,
     borrows_out_of_scope_at_location: FxIndexMap<Location, Vec<BorrowIndex>>,
 }
 
-impl<'mir, 'tcx> OutOfScopePrecomputer<'mir, 'tcx> {
+impl<'a, 'tcx> OutOfScopePrecomputer<'a, 'tcx> {
-    fn new(body: &'mir Body<'tcx>, regioncx: &'mir RegionInferenceContext<'tcx>) -> Self {
+    fn new(body: &'a Body<'tcx>, regioncx: &'a RegionInferenceContext<'tcx>) -> Self {
         OutOfScopePrecomputer {
             visited: BitSet::new_empty(body.basic_blocks.len()),
             visit_stack: vec![],
@@ -224,17 +224,17 @@ pub fn calculate_borrows_out_of_scope_at_location<'tcx>(
     prec.borrows_out_of_scope_at_location
 }
 
-struct PoloniusOutOfScopePrecomputer<'mir, 'tcx> {
+struct PoloniusOutOfScopePrecomputer<'a, 'tcx> {
     visited: BitSet<mir::BasicBlock>,
     visit_stack: Vec<mir::BasicBlock>,
-    body: &'mir Body<'tcx>,
+    body: &'a Body<'tcx>,
-    regioncx: &'mir RegionInferenceContext<'tcx>,
+    regioncx: &'a RegionInferenceContext<'tcx>,
 
     loans_out_of_scope_at_location: FxIndexMap<Location, Vec<BorrowIndex>>,
 }
 
-impl<'mir, 'tcx> PoloniusOutOfScopePrecomputer<'mir, 'tcx> {
+impl<'a, 'tcx> PoloniusOutOfScopePrecomputer<'a, 'tcx> {
-    fn new(body: &'mir Body<'tcx>, regioncx: &'mir RegionInferenceContext<'tcx>) -> Self {
+    fn new(body: &'a Body<'tcx>, regioncx: &'a RegionInferenceContext<'tcx>) -> Self {
         Self {
             visited: BitSet::new_empty(body.basic_blocks.len()),
             visit_stack: vec![],

compiler/rustc_borrowck/src/diagnostics/conflict_errors.rs

@@ -3553,7 +3553,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
         location: Location,
         mpi: MovePathIndex,
     ) -> (Vec<MoveSite>, Vec<Location>) {
-        fn predecessor_locations<'tcx, 'a>(
+        fn predecessor_locations<'a, 'tcx>(
             body: &'a mir::Body<'tcx>,
             location: Location,
         ) -> impl Iterator<Item = Location> + Captures<'tcx> + 'a {

compiler/rustc_borrowck/src/diagnostics/find_use.rs

@@ -21,15 +21,15 @@ pub(crate) fn find<'tcx>(
     uf.find()
 }
 
-struct UseFinder<'cx, 'tcx> {
+struct UseFinder<'a, 'tcx> {
-    body: &'cx Body<'tcx>,
+    body: &'a Body<'tcx>,
-    regioncx: &'cx Rc<RegionInferenceContext<'tcx>>,
+    regioncx: &'a Rc<RegionInferenceContext<'tcx>>,
     tcx: TyCtxt<'tcx>,
     region_vid: RegionVid,
     start_point: Location,
 }
 
-impl<'cx, 'tcx> UseFinder<'cx, 'tcx> {
+impl<'a, 'tcx> UseFinder<'a, 'tcx> {
     fn find(&mut self) -> Option<Cause> {
         let mut queue = VecDeque::new();
         let mut visited = FxIndexSet::default();
@@ -93,8 +93,8 @@ impl<'cx, 'tcx> UseFinder<'cx, 'tcx> {
     }
 }
 
-struct DefUseVisitor<'cx, 'tcx> {
+struct DefUseVisitor<'a, 'tcx> {
-    body: &'cx Body<'tcx>,
+    body: &'a Body<'tcx>,
     tcx: TyCtxt<'tcx>,
     region_vid: RegionVid,
     def_use_result: Option<DefUseResult>,
@@ -106,7 +106,7 @@ enum DefUseResult {
     UseDrop { local: Local },
 }
 
-impl<'cx, 'tcx> Visitor<'tcx> for DefUseVisitor<'cx, 'tcx> {
+impl<'a, 'tcx> Visitor<'tcx> for DefUseVisitor<'a, 'tcx> {
     fn visit_local(&mut self, local: Local, context: PlaceContext, _: Location) {
         let local_ty = self.body.local_decls[local].ty;
 

compiler/rustc_borrowck/src/diagnostics/mutability_errors.rs

@@ -558,7 +558,7 @@ impl<'infcx, 'tcx> MirBorrowckCtxt<'_, 'infcx, 'tcx> {
                 ty: Ty<'tcx>,
                 suggested: bool,
             }
-            impl<'a, 'cx, 'tcx> Visitor<'tcx> for SuggestIndexOperatorAlternativeVisitor<'a, 'cx, 'tcx> {
+            impl<'a, 'infcx, 'tcx> Visitor<'tcx> for SuggestIndexOperatorAlternativeVisitor<'a, 'infcx, 'tcx> {
                 fn visit_stmt(&mut self, stmt: &'tcx hir::Stmt<'tcx>) {
                     hir::intravisit::walk_stmt(self, stmt);
                     let expr = match stmt.kind {

compiler/rustc_borrowck/src/polonius/loan_invalidations.rs

@@ -32,18 +32,18 @@ pub(super) fn emit_loan_invalidations<'tcx>(
     visitor.visit_body(body);
 }
 
-struct LoanInvalidationsGenerator<'cx, 'tcx> {
+struct LoanInvalidationsGenerator<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
-    all_facts: &'cx mut AllFacts,
+    all_facts: &'a mut AllFacts,
-    location_table: &'cx LocationTable,
+    location_table: &'a LocationTable,
-    body: &'cx Body<'tcx>,
+    body: &'a Body<'tcx>,
-    dominators: &'cx Dominators<BasicBlock>,
+    dominators: &'a Dominators<BasicBlock>,
-    borrow_set: &'cx BorrowSet<'tcx>,
+    borrow_set: &'a BorrowSet<'tcx>,
 }
 
 /// Visits the whole MIR and generates `invalidates()` facts.
 /// Most of the code implementing this was stolen from `borrow_check/mod.rs`.
-impl<'cx, 'tcx> Visitor<'tcx> for LoanInvalidationsGenerator<'cx, 'tcx> {
+impl<'a, 'tcx> Visitor<'tcx> for LoanInvalidationsGenerator<'a, 'tcx> {
     fn visit_statement(&mut self, statement: &Statement<'tcx>, location: Location) {
         self.check_activations(location);
 
@@ -212,7 +212,7 @@ impl<'cx, 'tcx> Visitor<'tcx> for LoanInvalidationsGenerator<'cx, 'tcx> {
     }
 }
 
-impl<'cx, 'tcx> LoanInvalidationsGenerator<'cx, 'tcx> {
+impl<'a, 'tcx> LoanInvalidationsGenerator<'a, 'tcx> {
     /// Simulates mutation of a place.
     fn mutate_place(&mut self, location: Location, place: Place<'tcx>, kind: AccessDepth) {
         self.access_place(

compiler/rustc_borrowck/src/polonius/loan_kills.rs

@@ -25,15 +25,15 @@ pub(super) fn emit_loan_kills<'tcx>(
     }
 }
 
-struct LoanKillsGenerator<'cx, 'tcx> {
+struct LoanKillsGenerator<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
-    all_facts: &'cx mut AllFacts,
+    all_facts: &'a mut AllFacts,
-    location_table: &'cx LocationTable,
+    location_table: &'a LocationTable,
-    borrow_set: &'cx BorrowSet<'tcx>,
+    borrow_set: &'a BorrowSet<'tcx>,
-    body: &'cx Body<'tcx>,
+    body: &'a Body<'tcx>,
 }
 
-impl<'cx, 'tcx> Visitor<'tcx> for LoanKillsGenerator<'cx, 'tcx> {
+impl<'a, 'tcx> Visitor<'tcx> for LoanKillsGenerator<'a, 'tcx> {
     fn visit_statement(&mut self, statement: &Statement<'tcx>, location: Location) {
         // Also record CFG facts here.
         self.all_facts.cfg_edge.push((

compiler/rustc_borrowck/src/type_check/free_region_relations.rs

@@ -181,12 +181,12 @@ impl UniversalRegionRelations<'_> {
     }
 }
 
-struct UniversalRegionRelationsBuilder<'this, 'tcx> {
+struct UniversalRegionRelationsBuilder<'a, 'tcx> {
-    infcx: &'this InferCtxt<'tcx>,
+    infcx: &'a InferCtxt<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
     universal_regions: Rc<UniversalRegions<'tcx>>,
     implicit_region_bound: ty::Region<'tcx>,
-    constraints: &'this mut MirTypeckRegionConstraints<'tcx>,
+    constraints: &'a mut MirTypeckRegionConstraints<'tcx>,
 
     // outputs:
     outlives: TransitiveRelationBuilder<RegionVid>,

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

@@ -148,12 +148,12 @@ fn record_regular_live_regions<'tcx>(
 }
 
 /// Visitor looking for regions that should be live within rvalues or calls.
-struct LiveVariablesVisitor<'cx, 'tcx> {
+struct LiveVariablesVisitor<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
-    liveness_constraints: &'cx mut LivenessValues,
+    liveness_constraints: &'a mut LivenessValues,
 }
 
-impl<'cx, 'tcx> Visitor<'tcx> for LiveVariablesVisitor<'cx, 'tcx> {
+impl<'a, 'tcx> Visitor<'tcx> for LiveVariablesVisitor<'a, 'tcx> {
     /// We sometimes have `args` within an rvalue, or within a
     /// call. Make them live at the location where they appear.
     fn visit_args(&mut self, args: &GenericArgsRef<'tcx>, location: Location) {
@@ -188,7 +188,7 @@ impl<'cx, 'tcx> Visitor<'tcx> for LiveVariablesVisitor<'cx, 'tcx> {
     }
 }
 
-impl<'cx, 'tcx> LiveVariablesVisitor<'cx, 'tcx> {
+impl<'a, 'tcx> LiveVariablesVisitor<'a, 'tcx> {
     /// Some variable is "regular live" at `location` -- i.e., it may be used later. This means that
     /// all regions appearing in the type of `value` must be live at `location`.
     fn record_regions_live_at<T>(&mut self, value: T, location: Location)

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

@@ -11,13 +11,13 @@ use crate::location::{LocationIndex, LocationTable};
 type VarPointRelation = Vec<(Local, LocationIndex)>;
 type PathPointRelation = Vec<(MovePathIndex, LocationIndex)>;
 
-struct UseFactsExtractor<'me, 'tcx> {
+struct UseFactsExtractor<'a, 'tcx> {
-    var_defined_at: &'me mut VarPointRelation,
+    var_defined_at: &'a mut VarPointRelation,
-    var_used_at: &'me mut VarPointRelation,
+    var_used_at: &'a mut VarPointRelation,
-    location_table: &'me LocationTable,
+    location_table: &'a LocationTable,
-    var_dropped_at: &'me mut VarPointRelation,
+    var_dropped_at: &'a mut VarPointRelation,
-    move_data: &'me MoveData<'tcx>,
+    move_data: &'a MoveData<'tcx>,
-    path_accessed_at_base: &'me mut PathPointRelation,
+    path_accessed_at_base: &'a mut PathPointRelation,
 }
 
 // A Visitor to walk through the MIR and extract point-wise facts

compiler/rustc_borrowck/src/type_check/relate_tys.rs

@@ -58,8 +58,8 @@ impl<'a, 'tcx> TypeChecker<'a, 'tcx> {
     }
 }
 
-struct NllTypeRelating<'me, 'bccx, 'tcx> {
+struct NllTypeRelating<'a, 'b, 'tcx> {
-    type_checker: &'me mut TypeChecker<'bccx, 'tcx>,
+    type_checker: &'a mut TypeChecker<'b, 'tcx>,
 
     /// Where (and why) is this relation taking place?
     locations: Locations,
@@ -82,9 +82,9 @@ struct NllTypeRelating<'me, 'bccx, 'tcx> {
     ambient_variance_info: ty::VarianceDiagInfo<TyCtxt<'tcx>>,
 }
 
-impl<'me, 'bccx, 'tcx> NllTypeRelating<'me, 'bccx, 'tcx> {
+impl<'a, 'b, 'tcx> NllTypeRelating<'a, 'b, 'tcx> {
     fn new(
-        type_checker: &'me mut TypeChecker<'bccx, 'tcx>,
+        type_checker: &'a mut TypeChecker<'b, 'tcx>,
         locations: Locations,
         category: ConstraintCategory<'tcx>,
         universe_info: UniverseInfo<'tcx>,
@@ -309,7 +309,7 @@ impl<'me, 'bccx, 'tcx> NllTypeRelating<'me, 'bccx, 'tcx> {
     }
 }
 
-impl<'bccx, 'tcx> TypeRelation<TyCtxt<'tcx>> for NllTypeRelating<'_, 'bccx, 'tcx> {
+impl<'b, 'tcx> TypeRelation<TyCtxt<'tcx>> for NllTypeRelating<'_, 'b, 'tcx> {
     fn cx(&self) -> TyCtxt<'tcx> {
         self.type_checker.infcx.tcx
     }
@@ -520,7 +520,7 @@ impl<'bccx, 'tcx> TypeRelation<TyCtxt<'tcx>> for NllTypeRelating<'_, 'bccx, 'tcx
     }
 }
 
-impl<'bccx, 'tcx> PredicateEmittingRelation<InferCtxt<'tcx>> for NllTypeRelating<'_, 'bccx, 'tcx> {
+impl<'b, 'tcx> PredicateEmittingRelation<InferCtxt<'tcx>> for NllTypeRelating<'_, 'b, 'tcx> {
     fn span(&self) -> Span {
         self.locations.span(self.type_checker.body)
     }

compiler/rustc_builtin_macros/src/global_allocator.rs

@@ -65,7 +65,7 @@ struct AllocFnFactory<'a, 'b> {
     span: Span,
     ty_span: Span,
     global: Ident,
-    cx: &'b ExtCtxt<'a>,
+    cx: &'a ExtCtxt<'b>,
 }
 
 impl AllocFnFactory<'_, '_> {

compiler/rustc_const_eval/src/check_consts/check.rs

@@ -166,12 +166,12 @@ impl<'mir, 'tcx> Qualifs<'mir, 'tcx> {
     }
 }
 
-struct LocalReturnTyVisitor<'ck, 'mir, 'tcx> {
+struct LocalReturnTyVisitor<'a, 'mir, 'tcx> {
     kind: LocalKind,
-    checker: &'ck mut Checker<'mir, 'tcx>,
+    checker: &'a mut Checker<'mir, 'tcx>,
 }
 
-impl<'ck, 'mir, 'tcx> TypeVisitor<TyCtxt<'tcx>> for LocalReturnTyVisitor<'ck, 'mir, 'tcx> {
+impl<'a, 'mir, 'tcx> TypeVisitor<TyCtxt<'tcx>> for LocalReturnTyVisitor<'a, 'mir, 'tcx> {
     fn visit_ty(&mut self, t: Ty<'tcx>) {
         match t.kind() {
             ty::FnPtr(..) => {}

compiler/rustc_const_eval/src/interpret/memory.rs

@@ -1114,7 +1114,7 @@ impl<'a, 'tcx, M: Machine<'tcx>> std::fmt::Debug for DumpAllocs<'a, 'tcx, M> {
 }
 
 /// Reading and writing.
-impl<'tcx, 'a, Prov: Provenance, Extra, Bytes: AllocBytes>
+impl<'a, 'tcx, Prov: Provenance, Extra, Bytes: AllocBytes>
     AllocRefMut<'a, 'tcx, Prov, Extra, Bytes>
 {
     pub fn as_ref<'b>(&'b self) -> AllocRef<'b, 'tcx, Prov, Extra, Bytes> {
@@ -1162,7 +1162,7 @@ impl<'tcx, 'a, Prov: Provenance, Extra, Bytes: AllocBytes>
     }
 }
 
-impl<'tcx, 'a, Prov: Provenance, Extra, Bytes: AllocBytes> AllocRef<'a, 'tcx, Prov, Extra, Bytes> {
+impl<'a, 'tcx, Prov: Provenance, Extra, Bytes: AllocBytes> AllocRef<'a, 'tcx, Prov, Extra, Bytes> {
     /// `range` is relative to this allocation reference, not the base of the allocation.
     pub fn read_scalar(
         &self,

compiler/rustc_const_eval/src/interpret/projection.rs

@@ -101,7 +101,7 @@ pub trait Projectable<'tcx, Prov: Provenance>: Sized + std::fmt::Debug {
 }
 
 /// A type representing iteration over the elements of an array.
-pub struct ArrayIterator<'tcx, 'a, Prov: Provenance, P: Projectable<'tcx, Prov>> {
+pub struct ArrayIterator<'a, 'tcx, Prov: Provenance, P: Projectable<'tcx, Prov>> {
     base: &'a P,
     range: Range<u64>,
     stride: Size,
@@ -109,7 +109,7 @@ pub struct ArrayIterator<'tcx, 'a, Prov: Provenance, P: Projectable<'tcx, Prov>>
     _phantom: PhantomData<Prov>, // otherwise it says `Prov` is never used...
 }
 
-impl<'tcx, 'a, Prov: Provenance, P: Projectable<'tcx, Prov>> ArrayIterator<'tcx, 'a, Prov, P> {
+impl<'a, 'tcx, Prov: Provenance, P: Projectable<'tcx, Prov>> ArrayIterator<'a, 'tcx, Prov, P> {
     /// Should be the same `ecx` on each call, and match the one used to create the iterator.
     pub fn next<M: Machine<'tcx, Provenance = Prov>>(
         &mut self,
@@ -286,7 +286,7 @@ where
     pub fn project_array_fields<'a, P: Projectable<'tcx, M::Provenance>>(
         &self,
         base: &'a P,
-    ) -> InterpResult<'tcx, ArrayIterator<'tcx, 'a, M::Provenance, P>> {
+    ) -> InterpResult<'tcx, ArrayIterator<'a, 'tcx, M::Provenance, P>> {
         let abi::FieldsShape::Array { stride, .. } = base.layout().fields else {
             span_bug!(self.cur_span(), "project_array_fields: expected an array layout");
         };

compiler/rustc_driver_impl/src/lib.rs

@@ -207,17 +207,17 @@ pub fn diagnostics_registry() -> Registry {
 }
 
 /// This is the primary entry point for rustc.
-pub struct RunCompiler<'a, 'b> {
+pub struct RunCompiler<'a> {
     at_args: &'a [String],
-    callbacks: &'b mut (dyn Callbacks + Send),
+    callbacks: &'a mut (dyn Callbacks + Send),
     file_loader: Option<Box<dyn FileLoader + Send + Sync>>,
     make_codegen_backend:
         Option<Box<dyn FnOnce(&config::Options) -> Box<dyn CodegenBackend> + Send>>,
     using_internal_features: Arc<std::sync::atomic::AtomicBool>,
 }
 
-impl<'a, 'b> RunCompiler<'a, 'b> {
+impl<'a> RunCompiler<'a> {
-    pub fn new(at_args: &'a [String], callbacks: &'b mut (dyn Callbacks + Send)) -> Self {
+    pub fn new(at_args: &'a [String], callbacks: &'a mut (dyn Callbacks + Send)) -> Self {
         Self {
             at_args,
             callbacks,

compiler/rustc_expand/src/proc_macro.rs

@@ -43,9 +43,9 @@ pub struct BangProcMacro {
 }
 
 impl base::BangProcMacro for BangProcMacro {
-    fn expand<'cx>(
+    fn expand(
         &self,
-        ecx: &'cx mut ExtCtxt<'_>,
+        ecx: &mut ExtCtxt<'_>,
         span: Span,
         input: TokenStream,
     ) -> Result<TokenStream, ErrorGuaranteed> {
@@ -73,9 +73,9 @@ pub struct AttrProcMacro {
 }
 
 impl base::AttrProcMacro for AttrProcMacro {
-    fn expand<'cx>(
+    fn expand(
         &self,
-        ecx: &'cx mut ExtCtxt<'_>,
+        ecx: &mut ExtCtxt<'_>,
         span: Span,
         annotation: TokenStream,
         annotated: TokenStream,

compiler/rustc_hir_typeck/src/errors.rs

@@ -711,7 +711,7 @@ pub(crate) struct CastThinPointerToFatPointer<'tcx> {
 
 #[derive(Diagnostic)]
 #[diag(hir_typeck_pass_to_variadic_function, code = E0617)]
-pub(crate) struct PassToVariadicFunction<'tcx, 'a> {
+pub(crate) struct PassToVariadicFunction<'a, 'tcx> {
     #[primary_span]
     pub span: Span,
     pub ty: Ty<'tcx>,

compiler/rustc_hir_typeck/src/fallback.rs

@@ -603,12 +603,12 @@ fn compute_unsafe_infer_vars<'a, 'tcx>(
         root_ctxt.tcx.hir().maybe_body_owned_by(body_id).expect("body id must have an owner");
     let mut res = UnordMap::default();
 
-    struct UnsafeInferVarsVisitor<'a, 'tcx, 'r> {
+    struct UnsafeInferVarsVisitor<'a, 'tcx> {
         root_ctxt: &'a TypeckRootCtxt<'tcx>,
-        res: &'r mut UnordMap<ty::TyVid, (HirId, Span, UnsafeUseReason)>,
+        res: &'a mut UnordMap<ty::TyVid, (HirId, Span, UnsafeUseReason)>,
     }
 
-    impl Visitor<'_> for UnsafeInferVarsVisitor<'_, '_, '_> {
+    impl Visitor<'_> for UnsafeInferVarsVisitor<'_, '_> {
         fn visit_expr(&mut self, ex: &'_ hir::Expr<'_>) {
             let typeck_results = self.root_ctxt.typeck_results.borrow();
 

compiler/rustc_hir_typeck/src/fn_ctxt/_impl.rs

@@ -1234,7 +1234,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
             infer_args_for_err: &'a FxHashSet<usize>,
             segments: &'tcx [hir::PathSegment<'tcx>],
         }
-        impl<'tcx, 'a> GenericArgsLowerer<'a, 'tcx> for CtorGenericArgsCtxt<'a, 'tcx> {
+        impl<'a, 'tcx> GenericArgsLowerer<'a, 'tcx> for CtorGenericArgsCtxt<'a, 'tcx> {
             fn args_for_def_id(
                 &mut self,
                 def_id: DefId,

compiler/rustc_hir_typeck/src/pat.rs

@@ -83,7 +83,7 @@ struct TopInfo<'tcx> {
 }
 
 #[derive(Copy, Clone)]
-struct PatInfo<'tcx, 'a> {
+struct PatInfo<'a, 'tcx> {
     binding_mode: ByRef,
     max_ref_mutbl: MutblCap,
     top_info: &'a TopInfo<'tcx>,
@@ -222,7 +222,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
     /// Outside of this module, `check_pat_top` should always be used.
     /// Conversely, inside this module, `check_pat_top` should never be used.
     #[instrument(level = "debug", skip(self, pat_info))]
-    fn check_pat(&self, pat: &'tcx Pat<'tcx>, expected: Ty<'tcx>, pat_info: PatInfo<'tcx, '_>) {
+    fn check_pat(&self, pat: &'tcx Pat<'tcx>, expected: Ty<'tcx>, pat_info: PatInfo<'_, 'tcx>) {
         let PatInfo { binding_mode, max_ref_mutbl, top_info: ti, current_depth, .. } = pat_info;
 
         let path_res = match &pat.kind {
@@ -668,7 +668,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         ident: Ident,
         sub: Option<&'tcx Pat<'tcx>>,
         expected: Ty<'tcx>,
-        pat_info: PatInfo<'tcx, '_>,
+        pat_info: PatInfo<'_, 'tcx>,
     ) -> Ty<'tcx> {
         let PatInfo { binding_mode: def_br, top_info: ti, .. } = pat_info;
 
@@ -981,7 +981,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         fields: &'tcx [hir::PatField<'tcx>],
         has_rest_pat: bool,
         expected: Ty<'tcx>,
-        pat_info: PatInfo<'tcx, '_>,
+        pat_info: PatInfo<'_, 'tcx>,
     ) -> Ty<'tcx> {
         // Resolve the path and check the definition for errors.
         let (variant, pat_ty) = match self.check_struct_path(qpath, pat.hir_id) {
@@ -1184,7 +1184,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         subpats: &'tcx [Pat<'tcx>],
         ddpos: hir::DotDotPos,
         expected: Ty<'tcx>,
-        pat_info: PatInfo<'tcx, '_>,
+        pat_info: PatInfo<'_, 'tcx>,
     ) -> Ty<'tcx> {
         let tcx = self.tcx;
         let on_error = |e| {
@@ -1441,7 +1441,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         elements: &'tcx [Pat<'tcx>],
         ddpos: hir::DotDotPos,
         expected: Ty<'tcx>,
-        pat_info: PatInfo<'tcx, '_>,
+        pat_info: PatInfo<'_, 'tcx>,
     ) -> Ty<'tcx> {
         let tcx = self.tcx;
         let mut expected_len = elements.len();
@@ -1479,7 +1479,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         variant: &'tcx ty::VariantDef,
         fields: &'tcx [hir::PatField<'tcx>],
         has_rest_pat: bool,
-        pat_info: PatInfo<'tcx, '_>,
+        pat_info: PatInfo<'_, 'tcx>,
     ) -> Result<(), ErrorGuaranteed> {
         let tcx = self.tcx;
 
@@ -2070,7 +2070,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         span: Span,
         inner: &'tcx Pat<'tcx>,
         expected: Ty<'tcx>,
-        pat_info: PatInfo<'tcx, '_>,
+        pat_info: PatInfo<'_, 'tcx>,
     ) -> Ty<'tcx> {
         let tcx = self.tcx;
         let (box_ty, inner_ty) = self
@@ -2096,7 +2096,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         span: Span,
         inner: &'tcx Pat<'tcx>,
         expected: Ty<'tcx>,
-        pat_info: PatInfo<'tcx, '_>,
+        pat_info: PatInfo<'_, 'tcx>,
     ) -> Ty<'tcx> {
         let tcx = self.tcx;
         // Register a `DerefPure` bound, which is required by all `deref!()` pats.
@@ -2137,7 +2137,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         inner: &'tcx Pat<'tcx>,
         pat_mutbl: Mutability,
         mut expected: Ty<'tcx>,
-        mut pat_info: PatInfo<'tcx, '_>,
+        mut pat_info: PatInfo<'_, 'tcx>,
     ) -> Ty<'tcx> {
         let tcx = self.tcx;
         let features = tcx.features();
@@ -2345,7 +2345,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         slice: Option<&'tcx Pat<'tcx>>,
         after: &'tcx [Pat<'tcx>],
         expected: Ty<'tcx>,
-        pat_info: PatInfo<'tcx, '_>,
+        pat_info: PatInfo<'_, 'tcx>,
     ) -> Ty<'tcx> {
         let expected = self.try_structurally_resolve_type(span, expected);
 
@@ -2517,7 +2517,7 @@ impl<'a, 'tcx> FnCtxt<'a, 'tcx> {
         &self,
         span: Span,
         expected_ty: Ty<'tcx>,
-        pat_info: PatInfo<'tcx, '_>,
+        pat_info: PatInfo<'_, 'tcx>,
     ) -> ErrorGuaranteed {
         let PatInfo { top_info: ti, current_depth, .. } = pat_info;
 

compiler/rustc_lint/src/lints.rs

@@ -267,16 +267,16 @@ pub(crate) struct MacroExprFragment2024 {
     pub suggestion: Span,
 }
 
-pub(crate) struct BuiltinTypeAliasBounds<'a, 'hir> {
+pub(crate) struct BuiltinTypeAliasBounds<'hir> {
     pub in_where_clause: bool,
     pub label: Span,
     pub enable_feat_help: bool,
     pub suggestions: Vec<(Span, String)>,
     pub preds: &'hir [hir::WherePredicate<'hir>],
-    pub ty: Option<&'a hir::Ty<'hir>>,
+    pub ty: Option<&'hir hir::Ty<'hir>>,
 }
 
-impl<'a> LintDiagnostic<'a, ()> for BuiltinTypeAliasBounds<'_, '_> {
+impl<'a> LintDiagnostic<'a, ()> for BuiltinTypeAliasBounds<'_> {
     fn decorate_lint<'b>(self, diag: &'b mut Diag<'a, ()>) {
         diag.primary_message(if self.in_where_clause {
             fluent::lint_builtin_type_alias_bounds_where_clause

compiler/rustc_lint/src/tail_expr_drop_order.rs

@@ -143,18 +143,18 @@ impl<'tcx> LateLintPass<'tcx> for TailExprDropOrder {
     }
 }
 
-struct LintVisitor<'tcx, 'a> {
+struct LintVisitor<'a, 'tcx> {
     cx: &'a LateContext<'tcx>,
     // We only record locals that have significant drops
     locals: Vec<Span>,
 }
 
-struct LocalCollector<'tcx, 'a> {
+struct LocalCollector<'a, 'tcx> {
     cx: &'a LateContext<'tcx>,
     locals: &'a mut Vec<Span>,
 }
 
-impl<'tcx, 'a> Visitor<'tcx> for LocalCollector<'tcx, 'a> {
+impl<'a, 'tcx> Visitor<'tcx> for LocalCollector<'a, 'tcx> {
     type Result = ();
     fn visit_pat(&mut self, pat: &'tcx Pat<'tcx>) {
         if let PatKind::Binding(_binding_mode, id, ident, pat) = pat.kind {
@@ -171,7 +171,7 @@ impl<'tcx, 'a> Visitor<'tcx> for LocalCollector<'tcx, 'a> {
     }
 }
 
-impl<'tcx, 'a> Visitor<'tcx> for LintVisitor<'tcx, 'a> {
+impl<'a, 'tcx> Visitor<'tcx> for LintVisitor<'a, 'tcx> {
     fn visit_block(&mut self, block: &'tcx Block<'tcx>) {
         let mut locals = <_>::default();
         swap(&mut locals, &mut self.locals);
@@ -183,7 +183,7 @@ impl<'tcx, 'a> Visitor<'tcx> for LintVisitor<'tcx, 'a> {
     }
 }
 
-impl<'tcx, 'a> LintVisitor<'tcx, 'a> {
+impl<'a, 'tcx> LintVisitor<'a, 'tcx> {
     fn check_block_inner(&mut self, block: &Block<'tcx>) {
         if !block.span.at_least_rust_2024() {
             // We only lint for Edition 2024 onwards
@@ -205,13 +205,13 @@ impl<'tcx, 'a> LintVisitor<'tcx, 'a> {
     }
 }
 
-struct LintTailExpr<'tcx, 'a> {
+struct LintTailExpr<'a, 'tcx> {
     cx: &'a LateContext<'tcx>,
     is_root_tail_expr: bool,
     locals: &'a [Span],
 }
 
-impl<'tcx, 'a> LintTailExpr<'tcx, 'a> {
+impl<'a, 'tcx> LintTailExpr<'a, 'tcx> {
     fn expr_eventually_point_into_local(mut expr: &Expr<'tcx>) -> bool {
         loop {
             match expr.kind {
@@ -239,7 +239,7 @@ impl<'tcx, 'a> LintTailExpr<'tcx, 'a> {
     }
 }
 
-impl<'tcx, 'a> Visitor<'tcx> for LintTailExpr<'tcx, 'a> {
+impl<'a, 'tcx> Visitor<'tcx> for LintTailExpr<'a, 'tcx> {
     fn visit_expr(&mut self, expr: &'tcx Expr<'tcx>) {
         if self.is_root_tail_expr {
             self.is_root_tail_expr = false;

compiler/rustc_lint/src/types.rs

@@ -1713,13 +1713,13 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
         hir_ty: &hir::Ty<'tcx>,
         ty: Ty<'tcx>,
     ) -> Vec<(Ty<'tcx>, Span)> {
-        struct FnPtrFinder<'parent, 'a, 'tcx> {
+        struct FnPtrFinder<'a, 'b, 'tcx> {
-            visitor: &'parent ImproperCTypesVisitor<'a, 'tcx>,
+            visitor: &'a ImproperCTypesVisitor<'b, 'tcx>,
             spans: Vec<Span>,
             tys: Vec<Ty<'tcx>>,
         }
 
-        impl<'parent, 'a, 'tcx> hir::intravisit::Visitor<'_> for FnPtrFinder<'parent, 'a, 'tcx> {
+        impl<'a, 'b, 'tcx> hir::intravisit::Visitor<'_> for FnPtrFinder<'a, 'b, 'tcx> {
             fn visit_ty(&mut self, ty: &'_ hir::Ty<'_>) {
                 debug!(?ty);
                 if let hir::TyKind::BareFn(hir::BareFnTy { abi, .. }) = ty.kind
@@ -1732,7 +1732,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
             }
         }
 
-        impl<'vis, 'a, 'tcx> ty::visit::TypeVisitor<TyCtxt<'tcx>> for FnPtrFinder<'vis, 'a, 'tcx> {
+        impl<'a, 'b, 'tcx> ty::visit::TypeVisitor<TyCtxt<'tcx>> for FnPtrFinder<'a, 'b, 'tcx> {
             type Result = ControlFlow<Ty<'tcx>>;
 
             fn visit_ty(&mut self, ty: Ty<'tcx>) -> Self::Result {
@@ -1746,7 +1746,7 @@ impl<'a, 'tcx> ImproperCTypesVisitor<'a, 'tcx> {
             }
         }
 
-        let mut visitor = FnPtrFinder { visitor: &*self, spans: Vec::new(), tys: Vec::new() };
+        let mut visitor = FnPtrFinder { visitor: self, spans: Vec::new(), tys: Vec::new() };
         ty.visit_with(&mut visitor);
         hir::intravisit::Visitor::visit_ty(&mut visitor, hir_ty);
 

compiler/rustc_mir_build/src/build/custom/mod.rs

@@ -134,13 +134,12 @@ fn parse_attribute(attr: &Attribute) -> MirPhase {
     MirPhase::parse(dialect, phase)
 }
 
-struct ParseCtxt<'tcx, 'body> {
+struct ParseCtxt<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     param_env: ParamEnv<'tcx>,
-    thir: &'body Thir<'tcx>,
+    thir: &'a Thir<'tcx>,
     source_scope: SourceScope,
-
+    body: &'a mut Body<'tcx>,
-    body: &'body mut Body<'tcx>,
     local_map: FxHashMap<LocalVarId, Local>,
     block_map: FxHashMap<LocalVarId, BasicBlock>,
 }
@@ -151,7 +150,7 @@ struct ParseError {
     expected: String,
 }
 
-impl<'tcx, 'body> ParseCtxt<'tcx, 'body> {
+impl<'a, 'tcx> ParseCtxt<'a, 'tcx> {
     fn expr_error(&self, expr: ExprId, expected: &'static str) -> ParseError {
         let expr = &self.thir[expr];
         ParseError {

compiler/rustc_mir_build/src/build/custom/parse.rs

@@ -68,7 +68,7 @@ macro_rules! parse_by_kind {
 }
 pub(crate) use parse_by_kind;
 
-impl<'tcx, 'body> ParseCtxt<'tcx, 'body> {
+impl<'a, 'tcx> ParseCtxt<'a, 'tcx> {
     /// Expressions should only ever be matched on after preparsing them. This removes extra scopes
     /// we don't care about.
     fn preparse(&self, expr_id: ExprId) -> ExprId {

compiler/rustc_mir_build/src/build/custom/parse/instruction.rs

@@ -12,7 +12,7 @@ use super::{parse_by_kind, PResult, ParseCtxt};
 use crate::build::custom::ParseError;
 use crate::build::expr::as_constant::as_constant_inner;
 
-impl<'tcx, 'body> ParseCtxt<'tcx, 'body> {
+impl<'a, 'tcx> ParseCtxt<'a, 'tcx> {
     pub(crate) fn parse_statement(&self, expr_id: ExprId) -> PResult<StatementKind<'tcx>> {
         parse_by_kind!(self, expr_id, _, "statement",
             @call(mir_storage_live, args) => {

compiler/rustc_mir_dataflow/src/elaborate_drops.rs

@@ -155,11 +155,11 @@ pub trait DropElaborator<'a, 'tcx>: fmt::Debug {
 }
 
 #[derive(Debug)]
-struct DropCtxt<'l, 'b, 'tcx, D>
+struct DropCtxt<'a, 'b, 'tcx, D>
 where
     D: DropElaborator<'b, 'tcx>,
 {
-    elaborator: &'l mut D,
+    elaborator: &'a mut D,
 
     source_info: SourceInfo,
 
@@ -192,7 +192,7 @@ pub fn elaborate_drop<'b, 'tcx, D>(
     DropCtxt { elaborator, source_info, place, path, succ, unwind }.elaborate_drop(bb)
 }
 
-impl<'l, 'b, 'tcx, D> DropCtxt<'l, 'b, 'tcx, D>
+impl<'a, 'b, 'tcx, D> DropCtxt<'a, 'b, 'tcx, D>
 where
     D: DropElaborator<'b, 'tcx>,
     'tcx: 'b,

compiler/rustc_mir_dataflow/src/impls/storage_liveness.rs

@@ -17,7 +17,7 @@ impl<'a> MaybeStorageLive<'a> {
     }
 }
 
-impl<'tcx, 'a> crate::AnalysisDomain<'tcx> for MaybeStorageLive<'a> {
+impl<'a, 'tcx> crate::AnalysisDomain<'tcx> for MaybeStorageLive<'a> {
     type Domain = BitSet<Local>;
 
     const NAME: &'static str = "maybe_storage_live";
@@ -39,7 +39,7 @@ impl<'tcx, 'a> crate::AnalysisDomain<'tcx> for MaybeStorageLive<'a> {
     }
 }
 
-impl<'tcx, 'a> crate::GenKillAnalysis<'tcx> for MaybeStorageLive<'a> {
+impl<'a, 'tcx> crate::GenKillAnalysis<'tcx> for MaybeStorageLive<'a> {
     type Idx = Local;
 
     fn domain_size(&self, body: &Body<'tcx>) -> usize {
@@ -89,7 +89,7 @@ impl<'a> MaybeStorageDead<'a> {
     }
 }
 
-impl<'tcx, 'a> crate::AnalysisDomain<'tcx> for MaybeStorageDead<'a> {
+impl<'a, 'tcx> crate::AnalysisDomain<'tcx> for MaybeStorageDead<'a> {
     type Domain = BitSet<Local>;
 
     const NAME: &'static str = "maybe_storage_dead";
@@ -110,7 +110,7 @@ impl<'tcx, 'a> crate::AnalysisDomain<'tcx> for MaybeStorageDead<'a> {
     }
 }
 
-impl<'tcx, 'a> crate::GenKillAnalysis<'tcx> for MaybeStorageDead<'a> {
+impl<'a, 'tcx> crate::GenKillAnalysis<'tcx> for MaybeStorageDead<'a> {
     type Idx = Local;
 
     fn domain_size(&self, body: &Body<'tcx>) -> usize {

compiler/rustc_mir_transform/src/check_alignment.rs

@@ -62,14 +62,14 @@ impl<'tcx> crate::MirPass<'tcx> for CheckAlignment {
     }
 }
 
-struct PointerFinder<'tcx, 'a> {
+struct PointerFinder<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     local_decls: &'a mut LocalDecls<'tcx>,
     param_env: ParamEnv<'tcx>,
     pointers: Vec<(Place<'tcx>, Ty<'tcx>)>,
 }
 
-impl<'tcx, 'a> Visitor<'tcx> for PointerFinder<'tcx, 'a> {
+impl<'a, 'tcx> Visitor<'tcx> for PointerFinder<'a, 'tcx> {
     fn visit_place(&mut self, place: &Place<'tcx>, context: PlaceContext, location: Location) {
         // We want to only check reads and writes to Places, so we specifically exclude
         // Borrow and RawBorrow.

compiler/rustc_mir_transform/src/dataflow_const_prop.rs

@@ -554,13 +554,13 @@ impl<'tcx> Patch<'tcx> {
     }
 }
 
-struct Collector<'tcx, 'locals> {
+struct Collector<'a, 'tcx> {
     patch: Patch<'tcx>,
-    local_decls: &'locals LocalDecls<'tcx>,
+    local_decls: &'a LocalDecls<'tcx>,
 }
 
-impl<'tcx, 'locals> Collector<'tcx, 'locals> {
+impl<'a, 'tcx> Collector<'a, 'tcx> {
-    pub(crate) fn new(tcx: TyCtxt<'tcx>, local_decls: &'locals LocalDecls<'tcx>) -> Self {
+    pub(crate) fn new(tcx: TyCtxt<'tcx>, local_decls: &'a LocalDecls<'tcx>) -> Self {
         Self { patch: Patch::new(tcx), local_decls }
     }
 
@@ -722,7 +722,7 @@ fn try_write_constant<'tcx>(
 
 impl<'mir, 'tcx>
     ResultsVisitor<'mir, 'tcx, Results<'tcx, ValueAnalysisWrapper<ConstAnalysis<'_, 'tcx>>>>
-    for Collector<'tcx, '_>
+    for Collector<'_, 'tcx>
 {
     type Domain = State<FlatSet<Scalar>>;
 
@@ -839,9 +839,9 @@ impl<'tcx> MutVisitor<'tcx> for Patch<'tcx> {
     }
 }
 
-struct OperandCollector<'a, 'locals, 'tcx> {
+struct OperandCollector<'a, 'b, 'tcx> {
     state: &'a State<FlatSet<Scalar>>,
-    visitor: &'a mut Collector<'tcx, 'locals>,
+    visitor: &'a mut Collector<'b, 'tcx>,
     ecx: &'a mut InterpCx<'tcx, DummyMachine>,
     map: &'a Map<'tcx>,
 }

compiler/rustc_mir_transform/src/deduplicate_blocks.rs

@@ -98,7 +98,7 @@ fn find_duplicates(body: &Body<'_>) -> FxHashMap<BasicBlock, BasicBlock> {
     duplicates
 }
 
-struct BasicBlockHashable<'tcx, 'a> {
+struct BasicBlockHashable<'a, 'tcx> {
     basic_block_data: &'a BasicBlockData<'tcx>,
 }
 

compiler/rustc_mir_transform/src/elaborate_box_derefs.rs

@@ -38,7 +38,7 @@ pub(super) fn build_projection<'tcx>(
     ]
 }
 
-struct ElaborateBoxDerefVisitor<'tcx, 'a> {
+struct ElaborateBoxDerefVisitor<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     unique_did: DefId,
     nonnull_did: DefId,
@@ -46,7 +46,7 @@ struct ElaborateBoxDerefVisitor<'tcx, 'a> {
     patch: MirPatch<'tcx>,
 }
 
-impl<'tcx, 'a> MutVisitor<'tcx> for ElaborateBoxDerefVisitor<'tcx, 'a> {
+impl<'a, 'tcx> MutVisitor<'tcx> for ElaborateBoxDerefVisitor<'a, 'tcx> {
     fn tcx(&self) -> TyCtxt<'tcx> {
         self.tcx
     }

compiler/rustc_mir_transform/src/errors.rs

@@ -89,7 +89,7 @@ pub(crate) struct FnItemRef {
     pub ident: String,
 }
 
-pub(crate) struct MustNotSupend<'tcx, 'a> {
+pub(crate) struct MustNotSupend<'a, 'tcx> {
     pub tcx: TyCtxt<'tcx>,
     pub yield_sp: Span,
     pub reason: Option<MustNotSuspendReason>,

compiler/rustc_mir_transform/src/instsimplify.rs

@@ -63,13 +63,13 @@ impl<'tcx> crate::MirPass<'tcx> for InstSimplify {
     }
 }
 
-struct InstSimplifyContext<'tcx, 'a> {
+struct InstSimplifyContext<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     local_decls: &'a LocalDecls<'tcx>,
     param_env: ParamEnv<'tcx>,
 }
 
-impl<'tcx> InstSimplifyContext<'tcx, '_> {
+impl<'tcx> InstSimplifyContext<'_, 'tcx> {
     fn should_simplify(&self, source_info: &SourceInfo, rvalue: &Rvalue<'tcx>) -> bool {
         self.should_simplify_custom(source_info, "Rvalue", rvalue)
     }

compiler/rustc_mir_transform/src/jump_threading.rs

@@ -117,7 +117,7 @@ struct ThreadingOpportunity {
     target: BasicBlock,
 }
 
-struct TOFinder<'tcx, 'a> {
+struct TOFinder<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
     ecx: InterpCx<'tcx, DummyMachine>,
@@ -183,7 +183,7 @@ impl<'a> ConditionSet<'a> {
     }
 }
 
-impl<'tcx, 'a> TOFinder<'tcx, 'a> {
+impl<'a, 'tcx> TOFinder<'a, 'tcx> {
     fn is_empty(&self, state: &State<ConditionSet<'a>>) -> bool {
         state.all_bottom()
     }

compiler/rustc_mir_transform/src/match_branches.rs

@@ -295,7 +295,7 @@ struct SimplifyToExp {
 }
 
 #[derive(Clone, Copy)]
-enum ExpectedTransformKind<'tcx, 'a> {
+enum ExpectedTransformKind<'a, 'tcx> {
     /// Identical statements.
     Same(&'a StatementKind<'tcx>),
     /// Assignment statements have the same value.

compiler/rustc_mir_transform/src/ssa.rs

@@ -235,7 +235,7 @@ impl SsaLocals {
     }
 }
 
-struct SsaVisitor<'tcx, 'a> {
+struct SsaVisitor<'a, 'tcx> {
     body: &'a Body<'tcx>,
     dominators: &'a Dominators<BasicBlock>,
     assignments: IndexVec<Local, Set1<DefLocation>>,
@@ -261,7 +261,7 @@ impl SsaVisitor<'_, '_> {
     }
 }
 
-impl<'tcx> Visitor<'tcx> for SsaVisitor<'tcx, '_> {
+impl<'tcx> Visitor<'tcx> for SsaVisitor<'_, 'tcx> {
     fn visit_local(&mut self, local: Local, ctxt: PlaceContext, loc: Location) {
         match ctxt {
             PlaceContext::MutatingUse(MutatingUseContext::Projection)

compiler/rustc_passes/src/errors.rs

@@ -1012,12 +1012,12 @@ pub(crate) struct FeatureStableTwice {
 
 #[derive(Diagnostic)]
 #[diag(passes_feature_previously_declared, code = E0711)]
-pub(crate) struct FeaturePreviouslyDeclared<'a, 'b> {
+pub(crate) struct FeaturePreviouslyDeclared<'a> {
     #[primary_span]
     pub span: Span,
     pub feature: Symbol,
     pub declared: &'a str,
-    pub prev_declared: &'b str,
+    pub prev_declared: &'a str,
 }
 
 pub(crate) struct BreakNonLoop<'a> {

compiler/rustc_passes/src/loops.rs

@@ -9,7 +9,6 @@ use rustc_middle::hir::nested_filter;
 use rustc_middle::query::Providers;
 use rustc_middle::span_bug;
 use rustc_middle::ty::TyCtxt;
-use rustc_session::Session;
 use rustc_span::hygiene::DesugaringKind;
 use rustc_span::{BytePos, Span};
 use Context::*;
@@ -64,8 +63,7 @@ impl fmt::Display for BreakContextKind {
 }
 
 #[derive(Clone)]
-struct CheckLoopVisitor<'a, 'tcx> {
+struct CheckLoopVisitor<'tcx> {
-    sess: &'a Session,
     tcx: TyCtxt<'tcx>,
     // Keep track of a stack of contexts, so that suggestions
     // are not made for contexts where it would be incorrect,
@@ -76,12 +74,8 @@ struct CheckLoopVisitor<'a, 'tcx> {
 }
 
 fn check_mod_loops(tcx: TyCtxt<'_>, module_def_id: LocalModDefId) {
-    let mut check = CheckLoopVisitor {
+    let mut check =
-        sess: tcx.sess,
+        CheckLoopVisitor { tcx, cx_stack: vec![Normal], block_breaks: Default::default() };
-        tcx,
-        cx_stack: vec![Normal],
-        block_breaks: Default::default(),
-    };
     tcx.hir().visit_item_likes_in_module(module_def_id, &mut check);
     check.report_outside_loop_error();
 }
@@ -90,7 +84,7 @@ pub(crate) fn provide(providers: &mut Providers) {
     *providers = Providers { check_mod_loops, ..*providers };
 }
 
-impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
+impl<'hir> Visitor<'hir> for CheckLoopVisitor<'hir> {
     type NestedFilter = nested_filter::OnlyBodies;
 
     fn nested_visit_map(&mut self) -> Self::Map {
@@ -129,7 +123,7 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
             hir::ExprKind::If(cond, then, else_opt) => {
                 self.visit_expr(cond);
 
-                let get_block = |ck_loop: &CheckLoopVisitor<'a, 'hir>,
+                let get_block = |ck_loop: &CheckLoopVisitor<'hir>,
                                  expr: &hir::Expr<'hir>|
                  -> Option<&hir::Block<'hir>> {
                     if let hir::ExprKind::Block(b, None) = expr.kind
@@ -213,7 +207,7 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
                     Ok(loop_id) => Some(loop_id),
                     Err(hir::LoopIdError::OutsideLoopScope) => None,
                     Err(hir::LoopIdError::UnlabeledCfInWhileCondition) => {
-                        self.sess.dcx().emit_err(UnlabeledCfInWhileCondition {
+                        self.tcx.dcx().emit_err(UnlabeledCfInWhileCondition {
                             span: e.span,
                             cf_type: "break",
                         });
@@ -248,7 +242,7 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
                                     .label
                                     .map_or_else(String::new, |l| format!(" {}", l.ident))
                             );
-                            self.sess.dcx().emit_err(BreakNonLoop {
+                            self.tcx.dcx().emit_err(BreakNonLoop {
                                 span: e.span,
                                 head,
                                 kind: kind.name(),
@@ -280,14 +274,14 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
                 match destination.target_id {
                     Ok(loop_id) => {
                         if let Node::Block(block) = self.tcx.hir_node(loop_id) {
-                            self.sess.dcx().emit_err(ContinueLabeledBlock {
+                            self.tcx.dcx().emit_err(ContinueLabeledBlock {
                                 span: e.span,
                                 block_span: block.span,
                             });
                         }
                     }
                     Err(hir::LoopIdError::UnlabeledCfInWhileCondition) => {
-                        self.sess.dcx().emit_err(UnlabeledCfInWhileCondition {
+                        self.tcx.dcx().emit_err(UnlabeledCfInWhileCondition {
                             span: e.span,
                             cf_type: "continue",
                         });
@@ -306,10 +300,10 @@ impl<'a, 'hir> Visitor<'hir> for CheckLoopVisitor<'a, 'hir> {
     }
 }
 
-impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
+impl<'hir> CheckLoopVisitor<'hir> {
     fn with_context<F>(&mut self, cx: Context, f: F)
     where
-        F: FnOnce(&mut CheckLoopVisitor<'a, 'hir>),
+        F: FnOnce(&mut CheckLoopVisitor<'hir>),
     {
         self.cx_stack.push(cx);
         f(self);
@@ -326,7 +320,7 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
         match self.cx_stack[cx_pos] {
             LabeledBlock | Loop(_) => {}
             Closure(closure_span) => {
-                self.sess.dcx().emit_err(BreakInsideClosure {
+                self.tcx.dcx().emit_err(BreakInsideClosure {
                     span,
                     closure_span,
                     name: &br_cx_kind.to_string(),
@@ -343,7 +337,7 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
                     hir::CoroutineSource::Closure => "closure",
                     hir::CoroutineSource::Fn => "function",
                 };
-                self.sess.dcx().emit_err(BreakInsideCoroutine {
+                self.tcx.dcx().emit_err(BreakInsideCoroutine {
                     span,
                     coroutine_span,
                     name: &br_cx_kind.to_string(),
@@ -366,7 +360,7 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
                 self.require_break_cx(br_cx_kind, span, break_span, cx_pos - 1);
             }
             Normal | AnonConst | Fn | UnlabeledBlock(_) | UnlabeledIfBlock(_) | ConstBlock => {
-                self.sess.dcx().emit_err(OutsideLoop {
+                self.tcx.dcx().emit_err(OutsideLoop {
                     spans: vec![span],
                     name: &br_cx_kind.to_string(),
                     is_break: br_cx_kind == BreakContextKind::Break,
@@ -386,7 +380,7 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
             && self.cx_stack.last() == Some(&LabeledBlock)
             && label.label.is_none()
         {
-            self.sess.dcx().emit_err(UnlabeledInLabeledBlock { span, cf_type });
+            self.tcx.dcx().emit_err(UnlabeledInLabeledBlock { span, cf_type });
             return true;
         }
         false
@@ -394,7 +388,7 @@ impl<'a, 'hir> CheckLoopVisitor<'a, 'hir> {
 
     fn report_outside_loop_error(&self) {
         for (s, block) in &self.block_breaks {
-            self.sess.dcx().emit_err(OutsideLoop {
+            self.tcx.dcx().emit_err(OutsideLoop {
                 spans: block.spans.clone(),
                 name: &block.name,
                 is_break: true,

compiler/rustc_privacy/src/lib.rs

@@ -852,12 +852,12 @@ impl<'tcx> DefIdVisitor<'tcx> for ReachEverythingInTheInterfaceVisitor<'_, 'tcx>
 ////////////////////////////////////////////////////////////////////////////////
 /// Visitor, used for EffectiveVisibilities table checking
 ////////////////////////////////////////////////////////////////////////////////
-pub struct TestReachabilityVisitor<'tcx, 'a> {
+pub struct TestReachabilityVisitor<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     effective_visibilities: &'a EffectiveVisibilities,
 }
 
-impl<'tcx, 'a> TestReachabilityVisitor<'tcx, 'a> {
+impl<'a, 'tcx> TestReachabilityVisitor<'a, 'tcx> {
     fn effective_visibility_diagnostic(&mut self, def_id: LocalDefId) {
         if self.tcx.has_attr(def_id, sym::rustc_effective_visibility) {
             let mut error_msg = String::new();
@@ -878,7 +878,7 @@ impl<'tcx, 'a> TestReachabilityVisitor<'tcx, 'a> {
     }
 }
 
-impl<'tcx, 'a> Visitor<'tcx> for TestReachabilityVisitor<'tcx, 'a> {
+impl<'a, 'tcx> Visitor<'tcx> for TestReachabilityVisitor<'a, 'tcx> {
     fn visit_item(&mut self, item: &'tcx hir::Item<'tcx>) {
         self.effective_visibility_diagnostic(item.owner_id.def_id);
 
@@ -1425,12 +1425,12 @@ impl<'tcx> DefIdVisitor<'tcx> for SearchInterfaceForPrivateItemsVisitor<'tcx> {
     }
 }
 
-struct PrivateItemsInPublicInterfacesChecker<'tcx, 'a> {
+struct PrivateItemsInPublicInterfacesChecker<'a, 'tcx> {
     tcx: TyCtxt<'tcx>,
     effective_visibilities: &'a EffectiveVisibilities,
 }
 
-impl<'tcx> PrivateItemsInPublicInterfacesChecker<'tcx, '_> {
+impl<'tcx> PrivateItemsInPublicInterfacesChecker<'_, 'tcx> {
     fn check(
         &self,
         def_id: LocalDefId,

compiler/rustc_query_impl/src/profiling_support.rs

@@ -19,18 +19,18 @@ impl QueryKeyStringCache {
     }
 }
 
-struct QueryKeyStringBuilder<'p, 'tcx> {
+struct QueryKeyStringBuilder<'a, 'tcx> {
-    profiler: &'p SelfProfiler,
+    profiler: &'a SelfProfiler,
     tcx: TyCtxt<'tcx>,
-    string_cache: &'p mut QueryKeyStringCache,
+    string_cache: &'a mut QueryKeyStringCache,
 }
 
-impl<'p, 'tcx> QueryKeyStringBuilder<'p, 'tcx> {
+impl<'a, 'tcx> QueryKeyStringBuilder<'a, 'tcx> {
     fn new(
-        profiler: &'p SelfProfiler,
+        profiler: &'a SelfProfiler,
         tcx: TyCtxt<'tcx>,
-        string_cache: &'p mut QueryKeyStringCache,
+        string_cache: &'a mut QueryKeyStringCache,
-    ) -> QueryKeyStringBuilder<'p, 'tcx> {
+    ) -> QueryKeyStringBuilder<'a, 'tcx> {
         QueryKeyStringBuilder { profiler, tcx, string_cache }
     }
 

compiler/rustc_trait_selection/src/error_reporting/infer/region.rs

@@ -842,14 +842,14 @@ impl<'a, 'tcx> TypeErrCtxt<'a, 'tcx> {
         lifetime: Region<'tcx>,
         add_lt_suggs: &mut Vec<(Span, String)>,
     ) -> String {
-        struct LifetimeReplaceVisitor<'tcx, 'a> {
+        struct LifetimeReplaceVisitor<'a, 'tcx> {
             tcx: TyCtxt<'tcx>,
             needle: hir::LifetimeName,
             new_lt: &'a str,
             add_lt_suggs: &'a mut Vec<(Span, String)>,
         }
 
-        impl<'hir, 'tcx> hir::intravisit::Visitor<'hir> for LifetimeReplaceVisitor<'tcx, '_> {
+        impl<'hir, 'tcx> hir::intravisit::Visitor<'hir> for LifetimeReplaceVisitor<'_, 'tcx> {
             fn visit_lifetime(&mut self, lt: &'hir hir::Lifetime) {
                 if lt.res == self.needle {
                     self.add_lt_suggs.push(lt.suggestion(self.new_lt));

compiler/rustc_trait_selection/src/error_reporting/traits/suggestions.rs

@@ -61,9 +61,9 @@ pub enum CoroutineInteriorOrUpvar {
 // This type provides a uniform interface to retrieve data on coroutines, whether it originated from
 // the local crate being compiled or from a foreign crate.
 #[derive(Debug)]
-struct CoroutineData<'tcx, 'a>(&'a TypeckResults<'tcx>);
+struct CoroutineData<'a, 'tcx>(&'a TypeckResults<'tcx>);
 
-impl<'tcx, 'a> CoroutineData<'tcx, 'a> {
+impl<'a, 'tcx> CoroutineData<'a, 'tcx> {
     /// Try to get information about variables captured by the coroutine that matches a type we are
     /// looking for with `ty_matches` function. We uses it to find upvar which causes a failure to
     /// meet an obligation

compiler/rustc_trait_selection/src/traits/query/normalize.rs

@@ -25,7 +25,7 @@ use crate::traits::{
 };
 
 #[extension(pub trait QueryNormalizeExt<'tcx>)]
-impl<'cx, 'tcx> At<'cx, 'tcx> {
+impl<'a, 'tcx> At<'a, 'tcx> {
     /// Normalize `value` in the context of the inference context,
     /// yielding a resulting type, or an error if `value` cannot be
     /// normalized. If you don't care about regions, you should prefer
@@ -160,9 +160,9 @@ impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for MaxEscapingBoundVarVisitor {
     }
 }
 
-struct QueryNormalizer<'cx, 'tcx> {
+struct QueryNormalizer<'a, 'tcx> {
-    infcx: &'cx InferCtxt<'tcx>,
+    infcx: &'a InferCtxt<'tcx>,
-    cause: &'cx ObligationCause<'tcx>,
+    cause: &'a ObligationCause<'tcx>,
     param_env: ty::ParamEnv<'tcx>,
     obligations: Vec<PredicateObligation<'tcx>>,
     cache: SsoHashMap<Ty<'tcx>, Ty<'tcx>>,
@@ -170,7 +170,7 @@ struct QueryNormalizer<'cx, 'tcx> {
     universes: Vec<Option<ty::UniverseIndex>>,
 }
 
-impl<'cx, 'tcx> FallibleTypeFolder<TyCtxt<'tcx>> for QueryNormalizer<'cx, 'tcx> {
+impl<'a, 'tcx> FallibleTypeFolder<TyCtxt<'tcx>> for QueryNormalizer<'a, 'tcx> {
     type Error = NoSolution;
 
     fn cx(&self) -> TyCtxt<'tcx> {

compiler/rustc_trait_selection/src/traits/util.rs

@@ -332,8 +332,8 @@ pub fn with_replaced_escaping_bound_vars<
     }
 }
 
-pub struct BoundVarReplacer<'me, 'tcx> {
+pub struct BoundVarReplacer<'a, 'tcx> {
-    infcx: &'me InferCtxt<'tcx>,
+    infcx: &'a InferCtxt<'tcx>,
     // These three maps track the bound variable that were replaced by placeholders. It might be
     // nice to remove these since we already have the `kind` in the placeholder; we really just need
     // the `var` (but we *could* bring that into scope if we were to track them as we pass them).
@@ -345,15 +345,15 @@ pub struct BoundVarReplacer<'me, 'tcx> {
     current_index: ty::DebruijnIndex,
     // The `UniverseIndex` of the binding levels above us. These are optional, since we are lazy:
     // we don't actually create a universe until we see a bound var we have to replace.
-    universe_indices: &'me mut Vec<Option<ty::UniverseIndex>>,
+    universe_indices: &'a mut Vec<Option<ty::UniverseIndex>>,
 }
 
-impl<'me, 'tcx> BoundVarReplacer<'me, 'tcx> {
+impl<'a, 'tcx> BoundVarReplacer<'a, 'tcx> {
     /// Returns `Some` if we *were* able to replace bound vars. If there are any bound vars that
     /// use a binding level above `universe_indices.len()`, we fail.
     pub fn replace_bound_vars<T: TypeFoldable<TyCtxt<'tcx>>>(
-        infcx: &'me InferCtxt<'tcx>,
+        infcx: &'a InferCtxt<'tcx>,
-        universe_indices: &'me mut Vec<Option<ty::UniverseIndex>>,
+        universe_indices: &'a mut Vec<Option<ty::UniverseIndex>>,
         value: T,
     ) -> (
         T,
@@ -479,22 +479,22 @@ impl<'tcx> TypeFolder<TyCtxt<'tcx>> for BoundVarReplacer<'_, 'tcx> {
 }
 
 /// The inverse of [`BoundVarReplacer`]: replaces placeholders with the bound vars from which they came.
-pub struct PlaceholderReplacer<'me, 'tcx> {
+pub struct PlaceholderReplacer<'a, 'tcx> {
-    infcx: &'me InferCtxt<'tcx>,
+    infcx: &'a InferCtxt<'tcx>,
     mapped_regions: FxIndexMap<ty::PlaceholderRegion, ty::BoundRegion>,
     mapped_types: FxIndexMap<ty::PlaceholderType, ty::BoundTy>,
     mapped_consts: BTreeMap<ty::PlaceholderConst, ty::BoundVar>,
-    universe_indices: &'me [Option<ty::UniverseIndex>],
+    universe_indices: &'a [Option<ty::UniverseIndex>],
     current_index: ty::DebruijnIndex,
 }
 
-impl<'me, 'tcx> PlaceholderReplacer<'me, 'tcx> {
+impl<'a, 'tcx> PlaceholderReplacer<'a, 'tcx> {
     pub fn replace_placeholders<T: TypeFoldable<TyCtxt<'tcx>>>(
-        infcx: &'me InferCtxt<'tcx>,
+        infcx: &'a InferCtxt<'tcx>,
         mapped_regions: FxIndexMap<ty::PlaceholderRegion, ty::BoundRegion>,
         mapped_types: FxIndexMap<ty::PlaceholderType, ty::BoundTy>,
         mapped_consts: BTreeMap<ty::PlaceholderConst, ty::BoundVar>,
-        universe_indices: &'me [Option<ty::UniverseIndex>],
+        universe_indices: &'a [Option<ty::UniverseIndex>],
         value: T,
     ) -> T {
         let mut replacer = PlaceholderReplacer {

compiler/rustc_ty_utils/src/layout_sanity_check.rs

@@ -28,7 +28,7 @@ pub(super) fn sanity_check_layout<'tcx>(
     }
 
     /// Yields non-ZST fields of the type
-    fn non_zst_fields<'tcx, 'a>(
+    fn non_zst_fields<'a, 'tcx>(
         cx: &'a LayoutCx<'tcx, TyCtxt<'tcx>>,
         layout: &'a TyAndLayout<'tcx>,
     ) -> impl Iterator<Item = (Size, TyAndLayout<'tcx>)> + 'a {

src/librustdoc/html/render/search_index.rs

@@ -847,7 +847,7 @@ enum SimplifiedParam {
 ///
 /// This function also works recursively.
 #[instrument(level = "trace", skip(tcx, res, rgen, cache))]
-fn simplify_fn_type<'tcx, 'a>(
+fn simplify_fn_type<'a, 'tcx>(
     self_: Option<&'a Type>,
     generics: &Generics,
     arg: &'a Type,
@@ -1192,7 +1192,7 @@ fn simplify_fn_type<'tcx, 'a>(
     }
 }
 
-fn simplify_fn_constraint<'tcx, 'a>(
+fn simplify_fn_constraint<'a, 'tcx>(
     self_: Option<&'a Type>,
     generics: &Generics,
     constraint: &'a clean::AssocItemConstraint,