rustc: Remove needless lifetimes

compiler/rustc_ast/src/util/comments.rs

@@ -51,7 +51,7 @@ pub fn beautify_doc_string(data: Symbol, kind: CommentKind) -> Symbol {
         if i != 0 || j != lines.len() { Some((i, j)) } else { None }
     }
 
-    fn get_horizontal_trim<'a>(lines: &'a [&str], kind: CommentKind) -> Option<String> {
+    fn get_horizontal_trim(lines: &[&str], kind: CommentKind) -> Option<String> {
         let mut i = usize::MAX;
         let mut first = true;
 

compiler/rustc_ast_lowering/src/lib.rs

@@ -414,7 +414,7 @@ fn compute_hir_hash(
     })
 }
 
-pub fn lower_to_hir<'hir>(tcx: TyCtxt<'hir>, (): ()) -> hir::Crate<'hir> {
+pub fn lower_to_hir(tcx: TyCtxt<'_>, (): ()) -> hir::Crate<'_> {
     let sess = tcx.sess;
     let krate = tcx.untracked_crate.steal();
     let mut resolver = tcx.resolver_for_lowering(()).steal();

compiler/rustc_borrowck/src/consumers.rs

@@ -28,10 +28,10 @@ pub use super::{
 ///     that shows how to do this at `src/test/run-make/obtain-borrowck/`.
 ///
 /// *   Polonius is highly unstable, so expect regular changes in its signature or other details.
-pub fn get_body_with_borrowck_facts<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub fn get_body_with_borrowck_facts(
+    tcx: TyCtxt<'_>,
     def: ty::WithOptConstParam<LocalDefId>,
-) -> BodyWithBorrowckFacts<'tcx> {
+) -> BodyWithBorrowckFacts<'_> {
     let (input_body, promoted) = tcx.mir_promoted(def);
     let infcx = tcx.infer_ctxt().with_opaque_type_inference(DefiningAnchor::Bind(def.did)).build();
     let input_body: &Body<'_> = &input_body.borrow();

compiler/rustc_borrowck/src/diagnostics/find_all_local_uses.rs

@@ -9,7 +9,7 @@ use rustc_middle::mir::{Body, Local, Location};
 /// Find all uses of (including assignments to) a [`Local`].
 ///
 /// Uses `BTreeSet` so output is deterministic.
-pub(super) fn find<'tcx>(body: &Body<'tcx>, local: Local) -> BTreeSet<Location> {
+pub(super) fn find(body: &Body<'_>, local: Local) -> BTreeSet<Location> {
     let mut visitor = AllLocalUsesVisitor { for_local: local, uses: BTreeSet::default() };
     visitor.visit_body(body);
     visitor.uses

compiler/rustc_borrowck/src/lib.rs

@@ -124,10 +124,7 @@ pub fn provide(providers: &mut Providers) {
     };
 }
 
-fn mir_borrowck<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    def: ty::WithOptConstParam<LocalDefId>,
-) -> &'tcx BorrowCheckResult<'tcx> {
+fn mir_borrowck(tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>) -> &BorrowCheckResult<'_> {
     let (input_body, promoted) = tcx.mir_promoted(def);
     debug!("run query mir_borrowck: {}", tcx.def_path_str(def.did.to_def_id()));
 

compiler/rustc_borrowck/src/type_check/free_region_relations.rs

@@ -85,7 +85,7 @@ impl UniversalRegionRelations<'_> {
     /// outlives `fr` and (b) is not local.
     ///
     /// (*) If there are multiple competing choices, we return all of them.
-    pub(crate) fn non_local_upper_bounds<'a>(&'a self, fr: RegionVid) -> Vec<RegionVid> {
+    pub(crate) fn non_local_upper_bounds(&self, fr: RegionVid) -> Vec<RegionVid> {
         debug!("non_local_upper_bound(fr={:?})", fr);
         let res = self.non_local_bounds(&self.inverse_outlives, fr);
         assert!(!res.is_empty(), "can't find an upper bound!?");
@@ -148,9 +148,9 @@ impl UniversalRegionRelations<'_> {
     /// Helper for `non_local_upper_bounds` and `non_local_lower_bounds`.
     /// Repeatedly invokes `postdom_parent` until we find something that is not
     /// local. Returns `None` if we never do so.
-    fn non_local_bounds<'a>(
+    fn non_local_bounds(
         &self,
-        relation: &'a TransitiveRelation<RegionVid>,
+        relation: &TransitiveRelation<RegionVid>,
         fr0: RegionVid,
     ) -> Vec<RegionVid> {
         // This method assumes that `fr0` is one of the universally

compiler/rustc_builtin_macros/src/asm.rs

@@ -352,7 +352,7 @@ pub fn parse_asm_args<'a>(
 ///
 /// This function must be called immediately after the option token is parsed.
 /// Otherwise, the suggestion will be incorrect.
-fn err_duplicate_option<'a>(p: &mut Parser<'a>, symbol: Symbol, span: Span) {
+fn err_duplicate_option(p: &mut Parser<'_>, symbol: Symbol, span: Span) {
     let mut err = p
         .sess
         .span_diagnostic

compiler/rustc_codegen_gcc/src/base.rs

@@ -52,7 +52,7 @@ pub fn linkage_to_gcc(linkage: Linkage) -> FunctionType {
     }
 }
 
-pub fn compile_codegen_unit<'tcx>(tcx: TyCtxt<'tcx>, cgu_name: Symbol, supports_128bit_integers: bool) -> (ModuleCodegen<GccContext>, u64) {
+pub fn compile_codegen_unit(tcx: TyCtxt<'_>, cgu_name: Symbol, supports_128bit_integers: bool) -> (ModuleCodegen<GccContext>, u64) {
     let prof_timer = tcx.prof.generic_activity("codegen_module");
     let start_time = Instant::now();
 

compiler/rustc_codegen_gcc/src/common.rs

@@ -44,7 +44,7 @@ pub fn bytes_in_context<'gcc, 'tcx>(cx: &CodegenCx<'gcc, 'tcx>, bytes: &[u8]) ->
     context.new_array_constructor(None, typ, &elements)
 }
 
-pub fn type_is_pointer<'gcc>(typ: Type<'gcc>) -> bool {
+pub fn type_is_pointer(typ: Type) -> bool {
     typ.get_pointee().is_some()
 }
 

compiler/rustc_codegen_gcc/src/lib.rs

@@ -161,7 +161,7 @@ impl ExtraBackendMethods for GccCodegenBackend {
         mods
     }
 
-    fn compile_codegen_unit<'tcx>(&self, tcx: TyCtxt<'tcx>, cgu_name: Symbol) -> (ModuleCodegen<Self::Module>, u64) {
+    fn compile_codegen_unit(&self, tcx: TyCtxt<'_>, cgu_name: Symbol) -> (ModuleCodegen<Self::Module>, u64) {
         base::compile_codegen_unit(tcx, cgu_name, *self.supports_128bit_integers.lock().expect("lock"))
     }
 

compiler/rustc_codegen_llvm/src/coverageinfo/mapgen.rs

@@ -30,7 +30,7 @@ use std::ffi::CString;
 /// implementing this Rust version, and though the format documentation is very explicit and
 /// detailed, some undocumented details in Clang's implementation (that may or may not be important)
 /// were also replicated for Rust's Coverage Map.
-pub fn finalize<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>) {
+pub fn finalize(cx: &CodegenCx<'_, '_>) {
     let tcx = cx.tcx;
 
     // Ensure the installed version of LLVM supports at least Coverage Map
@@ -284,7 +284,7 @@ fn save_function_record(
 /// "code coverage dead code cgu" during the partitioning process. This prevents us from generating
 /// code regions for the same function more than once which can lead to linker errors regarding
 /// duplicate symbols.
-fn add_unused_functions<'ll, 'tcx>(cx: &CodegenCx<'ll, 'tcx>) {
+fn add_unused_functions(cx: &CodegenCx<'_, '_>) {
     assert!(cx.codegen_unit.is_code_coverage_dead_code_cgu());
 
     let tcx = cx.tcx;

compiler/rustc_codegen_llvm/src/debuginfo/metadata.rs

@@ -111,7 +111,7 @@ macro_rules! return_if_di_node_created_in_meantime {
 
 /// Extract size and alignment from a TyAndLayout.
 #[inline]
-fn size_and_align_of<'tcx>(ty_and_layout: TyAndLayout<'tcx>) -> (Size, Align) {
+fn size_and_align_of(ty_and_layout: TyAndLayout<'_>) -> (Size, Align) {
     (ty_and_layout.size, ty_and_layout.align.abi)
 }
 

compiler/rustc_codegen_llvm/src/llvm/ffi.rs

@@ -2389,11 +2389,11 @@ extern "C" {
 
     pub fn LLVMRustSetDataLayoutFromTargetMachine<'a>(M: &'a Module, TM: &'a TargetMachine);
 
-    pub fn LLVMRustBuildOperandBundleDef<'a>(
+    pub fn LLVMRustBuildOperandBundleDef(
         Name: *const c_char,
-        Inputs: *const &'a Value,
+        Inputs: *const &'_ Value,
         NumInputs: c_uint,
-    ) -> &'a mut OperandBundleDef<'a>;
+    ) -> &mut OperandBundleDef<'_>;
     pub fn LLVMRustFreeOperandBundleDef<'a>(Bundle: &'a mut OperandBundleDef<'a>);
 
     pub fn LLVMRustPositionBuilderAtStart<'a>(B: &Builder<'a>, BB: &'a BasicBlock);

compiler/rustc_codegen_ssa/src/back/link.rs

@@ -607,21 +607,21 @@ fn link_dwarf_object<'a>(
     }
 
     impl<Relocations> ThorinSession<Relocations> {
-        fn alloc_mmap<'arena>(&'arena self, data: Mmap) -> &'arena Mmap {
+        fn alloc_mmap(&self, data: Mmap) -> &Mmap {
             (*self.arena_mmap.alloc(data)).borrow()
         }
     }
 
     impl<Relocations> thorin::Session<Relocations> for ThorinSession<Relocations> {
-        fn alloc_data<'arena>(&'arena self, data: Vec<u8>) -> &'arena [u8] {
+        fn alloc_data(&self, data: Vec<u8>) -> &[u8] {
             (*self.arena_data.alloc(data)).borrow()
         }
 
-        fn alloc_relocation<'arena>(&'arena self, data: Relocations) -> &'arena Relocations {
+        fn alloc_relocation(&self, data: Relocations) -> &Relocations {
             (*self.arena_relocations.alloc(data)).borrow()
         }
 
-        fn read_input<'arena>(&'arena self, path: &Path) -> std::io::Result<&'arena [u8]> {
+        fn read_input(&self, path: &Path) -> std::io::Result<&[u8]> {
             let file = File::open(&path)?;
             let mmap = (unsafe { Mmap::map(file) })?;
             Ok(self.alloc_mmap(mmap))

compiler/rustc_codegen_ssa/src/back/symbol_export.rs

@@ -163,10 +163,10 @@ fn is_reachable_non_generic_provider_extern(tcx: TyCtxt<'_>, def_id: DefId) -> b
     tcx.reachable_non_generics(def_id.krate).contains_key(&def_id)
 }
 
-fn exported_symbols_provider_local<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn exported_symbols_provider_local(
+    tcx: TyCtxt<'_>,
     cnum: CrateNum,
-) -> &'tcx [(ExportedSymbol<'tcx>, SymbolExportInfo)] {
+) -> &[(ExportedSymbol<'_>, SymbolExportInfo)] {
     assert_eq!(cnum, LOCAL_CRATE);
 
     if !tcx.sess.opts.output_types.should_codegen() {

compiler/rustc_codegen_ssa/src/debuginfo/mod.rs

@@ -10,7 +10,7 @@ pub mod type_names;
 /// NOTE: This is somewhat inconsistent right now: For empty enums and enums with a single
 ///       fieldless variant, we generate DW_TAG_struct_type, although a
 ///       DW_TAG_enumeration_type would be a better fit.
-pub fn wants_c_like_enum_debuginfo<'tcx>(enum_type_and_layout: TyAndLayout<'tcx>) -> bool {
+pub fn wants_c_like_enum_debuginfo(enum_type_and_layout: TyAndLayout<'_>) -> bool {
     match enum_type_and_layout.ty.kind() {
         ty::Adt(adt_def, _) => {
             if !adt_def.is_enum() {

compiler/rustc_codegen_ssa/src/meth.rs

@@ -65,7 +65,7 @@ impl<'a, 'tcx> VirtualIndex {
 
 /// This takes a valid `self` receiver type and extracts the principal trait
 /// ref of the type.
-fn expect_dyn_trait_in_self<'tcx>(ty: Ty<'tcx>) -> ty::PolyExistentialTraitRef<'tcx> {
+fn expect_dyn_trait_in_self(ty: Ty<'_>) -> ty::PolyExistentialTraitRef<'_> {
     for arg in ty.peel_refs().walk() {
         if let GenericArgKind::Type(ty) = arg.unpack() {
             if let ty::Dynamic(data, _, _) = ty.kind() {

compiler/rustc_codegen_ssa/src/target_features.rs

@@ -419,7 +419,7 @@ pub fn from_target_feature(
 
 /// Computes the set of target features used in a function for the purposes of
 /// inline assembly.
-fn asm_target_features<'tcx>(tcx: TyCtxt<'tcx>, did: DefId) -> &'tcx FxHashSet<Symbol> {
+fn asm_target_features(tcx: TyCtxt<'_>, did: DefId) -> &FxHashSet<Symbol> {
     let mut target_features = tcx.sess.unstable_target_features.clone();
     if tcx.def_kind(did).has_codegen_attrs() {
         let attrs = tcx.codegen_fn_attrs(did);

compiler/rustc_data_structures/src/profiling.rs

@@ -205,10 +205,7 @@ impl SelfProfilerRef {
     /// VerboseTimingGuard returned from this call is dropped. In addition to recording
     /// a measureme event, "verbose" generic activities also print a timing entry to
     /// stderr if the compiler is invoked with -Ztime-passes.
-    pub fn verbose_generic_activity<'a>(
-        &'a self,
-        event_label: &'static str,
-    ) -> VerboseTimingGuard<'a> {
+    pub fn verbose_generic_activity(&self, event_label: &'static str) -> VerboseTimingGuard<'_> {
         let message =
             if self.print_verbose_generic_activities { Some(event_label.to_owned()) } else { None };
 
@@ -216,11 +213,11 @@ impl SelfProfilerRef {
     }
 
     /// Like `verbose_generic_activity`, but with an extra arg.
-    pub fn verbose_generic_activity_with_arg<'a, A>(
-        &'a self,
+    pub fn verbose_generic_activity_with_arg<A>(
+        &self,
         event_label: &'static str,
         event_arg: A,
-    ) -> VerboseTimingGuard<'a>
+    ) -> VerboseTimingGuard<'_>
     where
         A: Borrow<str> + Into<String>,
     {

compiler/rustc_data_structures/src/transitive_relation.rs

@@ -199,7 +199,7 @@ impl<T: Eq + Hash + Copy> TransitiveRelation<T> {
     /// Viewing the relation as a graph, computes the "mutual
     /// immediate postdominator" of a set of points (if one
     /// exists). See `postdom_upper_bound` for details.
-    pub fn mutual_immediate_postdominator<'a>(&'a self, mut mubs: Vec<T>) -> Option<T> {
+    pub fn mutual_immediate_postdominator(&self, mut mubs: Vec<T>) -> Option<T> {
         loop {
             match mubs.len() {
                 0 => return None,

compiler/rustc_data_structures/src/unord.rs

@@ -178,7 +178,7 @@ impl<V: Eq + Hash> UnordSet<V> {
     }
 
     #[inline]
-    pub fn items<'a>(&'a self) -> UnordItems<&'a V, impl Iterator<Item = &'a V>> {
+    pub fn items(&self) -> UnordItems<&V, impl Iterator<Item = &V>> {
         UnordItems(self.inner.iter())
     }
 
@@ -255,7 +255,7 @@ impl<K: Eq + Hash, V> UnordMap<K, V> {
     }
 
     #[inline]
-    pub fn items<'a>(&'a self) -> UnordItems<(&'a K, &'a V), impl Iterator<Item = (&'a K, &'a V)>> {
+    pub fn items(&self) -> UnordItems<(&K, &V), impl Iterator<Item = (&K, &V)>> {
         UnordItems(self.inner.iter())
     }
 
@@ -311,7 +311,7 @@ impl<V> UnordBag<V> {
     }
 
     #[inline]
-    pub fn items<'a>(&'a self) -> UnordItems<&'a V, impl Iterator<Item = &'a V>> {
+    pub fn items(&self) -> UnordItems<&V, impl Iterator<Item = &V>> {
         UnordItems(self.inner.iter())
     }
 

compiler/rustc_error_messages/src/lib.rs

@@ -549,9 +549,7 @@ fn icu_locale_from_unic_langid(lang: LanguageIdentifier) -> Option<icu_locid::Lo
     icu_locid::Locale::try_from_bytes(lang.to_string().as_bytes()).ok()
 }
 
-pub fn fluent_value_from_str_list_sep_by_and<'source>(
-    l: Vec<Cow<'source, str>>,
-) -> FluentValue<'source> {
+pub fn fluent_value_from_str_list_sep_by_and(l: Vec<Cow<'_, str>>) -> FluentValue<'_> {
     // Fluent requires 'static value here for its AnyEq usages.
     #[derive(Clone, PartialEq, Debug)]
     struct FluentStrListSepByAnd(Vec<String>);

compiler/rustc_expand/src/mbe/quoted.rs

@@ -356,7 +356,7 @@ fn parse_sep_and_kleene_op(
 // `$$` or a meta-variable is the lhs of a macro but shouldn't.
 //
 // For example, `macro_rules! foo { ( ${length()} ) => {} }`
-fn span_dollar_dollar_or_metavar_in_the_lhs_err<'sess>(sess: &'sess ParseSess, token: &Token) {
+fn span_dollar_dollar_or_metavar_in_the_lhs_err(sess: &ParseSess, token: &Token) {
     sess.span_diagnostic
         .span_err(token.span, &format!("unexpected token: {}", pprust::token_to_string(token)));
     sess.span_diagnostic.span_note_without_error(

compiler/rustc_graphviz/src/lib.rs

@@ -164,7 +164,7 @@
 //!     fn node_id(&'a self, n: &Nd) -> dot::Id<'a> {
 //!         dot::Id::new(format!("N{}", n)).unwrap()
 //!     }
-//!     fn node_label<'b>(&'b self, n: &Nd) -> dot::LabelText<'b> {
+//!     fn node_label(&self, n: &Nd) -> dot::LabelText {
 //!         dot::LabelText::LabelStr(self.nodes[*n].into())
 //!     }
 //!     fn edge_label<'b>(&'b self, _: &Ed) -> dot::LabelText<'b> {

compiler/rustc_hir_analysis/src/check/check.rs

@@ -162,7 +162,7 @@ fn check_union_fields(tcx: TyCtxt<'_>, span: Span, item_def_id: LocalDefId) -> b
 }
 
 /// Check that a `static` is inhabited.
-fn check_static_inhabited<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) {
+fn check_static_inhabited(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     // Make sure statics are inhabited.
     // Other parts of the compiler assume that there are no uninhabited places. In principle it
     // would be enough to check this for `extern` statics, as statics with an initializer will
@@ -212,7 +212,7 @@ fn check_static_inhabited<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) {
 
 /// Checks that an opaque type does not contain cycles and does not use `Self` or `T::Foo`
 /// projections that would result in "inheriting lifetimes".
-fn check_opaque<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
+fn check_opaque(tcx: TyCtxt<'_>, id: hir::ItemId) {
     let item = tcx.hir().item(id);
     let hir::ItemKind::OpaqueTy(hir::OpaqueTy { origin, .. }) = item.kind else {
         tcx.sess.delay_span_bug(tcx.hir().span(id.hir_id()), "expected opaque item");
@@ -245,8 +245,8 @@ fn check_opaque<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
 /// Checks that an opaque type does not use `Self` or `T::Foo` projections that would result
 /// in "inheriting lifetimes".
 #[instrument(level = "debug", skip(tcx, span))]
-pub(super) fn check_opaque_for_inheriting_lifetimes<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub(super) fn check_opaque_for_inheriting_lifetimes(
+    tcx: TyCtxt<'_>,
     def_id: LocalDefId,
     span: Span,
 ) {
@@ -496,7 +496,7 @@ fn is_enum_of_nonnullable_ptr<'tcx>(
     matches!(field.ty(tcx, substs).kind(), ty::FnPtr(..) | ty::Ref(..))
 }
 
-fn check_static_linkage<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) {
+fn check_static_linkage(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     if tcx.codegen_fn_attrs(def_id).import_linkage.is_some() {
         if match tcx.type_of(def_id).kind() {
             ty::RawPtr(_) => false,
@@ -508,7 +508,7 @@ fn check_static_linkage<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) {
     }
 }
 
-fn check_item_type<'tcx>(tcx: TyCtxt<'tcx>, id: hir::ItemId) {
+fn check_item_type(tcx: TyCtxt<'_>, id: hir::ItemId) {
     debug!(
         "check_item_type(it.def_id={:?}, it.name={})",
         id.owner_id,
@@ -1160,7 +1160,7 @@ pub(super) fn check_transparent<'tcx>(tcx: TyCtxt<'tcx>, adt: ty::AdtDef<'tcx>)
 }
 
 #[allow(trivial_numeric_casts)]
-fn check_enum<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) {
+fn check_enum(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     let def = tcx.adt_def(def_id);
     def.destructor(tcx); // force the destructor to be evaluated
 

compiler/rustc_hir_analysis/src/check/compare_method.rs

@@ -1517,8 +1517,8 @@ fn compare_generic_param_kinds<'tcx>(
 }
 
 /// Use `tcx.compare_assoc_const_impl_item_with_trait_item` instead
-pub(crate) fn raw_compare_const_impl<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub(crate) fn raw_compare_const_impl(
+    tcx: TyCtxt<'_>,
     (impl_const_item_def, trait_const_item_def): (LocalDefId, DefId),
 ) -> Result<(), ErrorGuaranteed> {
     let impl_const_item = tcx.associated_item(impl_const_item_def);

compiler/rustc_hir_analysis/src/check/mod.rs

@@ -115,10 +115,10 @@ fn adt_destructor(tcx: TyCtxt<'_>, def_id: DefId) -> Option<ty::Destructor> {
 
 /// Given a `DefId` for an opaque type in return position, find its parent item's return
 /// expressions.
-fn get_owner_return_paths<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn get_owner_return_paths(
+    tcx: TyCtxt<'_>,
     def_id: LocalDefId,
-) -> Option<(LocalDefId, ReturnsVisitor<'tcx>)> {
+) -> Option<(LocalDefId, ReturnsVisitor<'_>)> {
     let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
     let parent_id = tcx.hir().get_parent_item(hir_id).def_id;
     tcx.hir().find_by_def_id(parent_id).and_then(|node| node.body_id()).map(|body_id| {

compiler/rustc_hir_analysis/src/check/wfcheck.rs

@@ -1673,7 +1673,7 @@ fn check_method_receiver<'tcx>(
     }
 }
 
-fn e0307<'tcx>(tcx: TyCtxt<'tcx>, span: Span, receiver_ty: Ty<'_>) {
+fn e0307(tcx: TyCtxt<'_>, span: Span, receiver_ty: Ty<'_>) {
     struct_span_err!(
         tcx.sess.diagnostic(),
         span,

compiler/rustc_hir_analysis/src/coherence/builtin.rs

@@ -171,7 +171,7 @@ fn visit_implementation_of_copy(tcx: TyCtxt<'_>, impl_did: LocalDefId) {
     }
 }
 
-fn visit_implementation_of_coerce_unsized<'tcx>(tcx: TyCtxt<'tcx>, impl_did: LocalDefId) {
+fn visit_implementation_of_coerce_unsized(tcx: TyCtxt<'_>, impl_did: LocalDefId) {
     debug!("visit_implementation_of_coerce_unsized: impl_did={:?}", impl_did);
 
     // Just compute this for the side-effects, in particular reporting
@@ -181,7 +181,7 @@ fn visit_implementation_of_coerce_unsized<'tcx>(tcx: TyCtxt<'tcx>, impl_did: Loc
     tcx.at(span).coerce_unsized_info(impl_did);
 }
 
-fn visit_implementation_of_dispatch_from_dyn<'tcx>(tcx: TyCtxt<'tcx>, impl_did: LocalDefId) {
+fn visit_implementation_of_dispatch_from_dyn(tcx: TyCtxt<'_>, impl_did: LocalDefId) {
     debug!("visit_implementation_of_dispatch_from_dyn: impl_did={:?}", impl_did);
 
     let impl_hir_id = tcx.hir().local_def_id_to_hir_id(impl_did);

compiler/rustc_hir_analysis/src/collect.rs

@@ -839,7 +839,7 @@ fn convert_variant(
     )
 }
 
-fn adt_def<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> ty::AdtDef<'tcx> {
+fn adt_def(tcx: TyCtxt<'_>, def_id: DefId) -> ty::AdtDef<'_> {
     use rustc_hir::*;
 
     let def_id = def_id.expect_local();

compiler/rustc_hir_analysis/src/collect/lifetimes.rs

@@ -276,7 +276,7 @@ fn resolve_lifetimes(tcx: TyCtxt<'_>, local_def_id: hir::OwnerId) -> ResolveLife
     rl
 }
 
-fn late_region_as_bound_region<'tcx>(tcx: TyCtxt<'tcx>, region: &Region) -> ty::BoundVariableKind {
+fn late_region_as_bound_region(tcx: TyCtxt<'_>, region: &Region) -> ty::BoundVariableKind {
     match region {
         Region::LateBound(_, _, def_id) => {
             let name = tcx.hir().name(tcx.hir().local_def_id_to_hir_id(def_id.expect_local()));
@@ -1018,7 +1018,7 @@ impl<'a, 'tcx> Visitor<'tcx> for LifetimeContext<'a, 'tcx> {
     }
 }
 
-fn object_lifetime_default<'tcx>(tcx: TyCtxt<'tcx>, param_def_id: DefId) -> ObjectLifetimeDefault {
+fn object_lifetime_default(tcx: TyCtxt<'_>, param_def_id: DefId) -> ObjectLifetimeDefault {
     debug_assert_eq!(tcx.def_kind(param_def_id), DefKind::TyParam);
     let param_def_id = param_def_id.expect_local();
     let parent_def_id = tcx.local_parent(param_def_id);

compiler/rustc_hir_analysis/src/collect/predicates_of.rs

@@ -318,10 +318,10 @@ fn gather_explicit_predicates_of(tcx: TyCtxt<'_>, def_id: DefId) -> ty::GenericP
     }
 }
 
-fn const_evaluatable_predicates_of<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn const_evaluatable_predicates_of(
+    tcx: TyCtxt<'_>,
     def_id: LocalDefId,
-) -> FxIndexSet<(ty::Predicate<'tcx>, Span)> {
+) -> FxIndexSet<(ty::Predicate<'_>, Span)> {
     struct ConstCollector<'tcx> {
         tcx: TyCtxt<'tcx>,
         preds: FxIndexSet<(ty::Predicate<'tcx>, Span)>,

compiler/rustc_hir_analysis/src/impl_wf_check/min_specialization.rs

@@ -157,11 +157,11 @@ fn check_constness(tcx: TyCtxt<'_>, impl1_def_id: LocalDefId, impl2_node: Node,
 /// ```
 ///
 /// Would return `S1 = [C]` and `S2 = [Vec<C>, C]`.
-fn get_impl_substs<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn get_impl_substs(
+    tcx: TyCtxt<'_>,
     impl1_def_id: LocalDefId,
     impl2_node: Node,
-) -> Option<(SubstsRef<'tcx>, SubstsRef<'tcx>)> {
+) -> Option<(SubstsRef<'_>, SubstsRef<'_>)> {
     let infcx = &tcx.infer_ctxt().build();
     let ocx = ObligationCtxt::new(infcx);
     let param_env = tcx.param_env(impl1_def_id);

compiler/rustc_hir_analysis/src/outlives/implicit_infer.rs

@@ -13,9 +13,9 @@ use super::utils::*;
 /// `global_inferred_outlives`: this is initially the empty map that
 ///     was generated by walking the items in the crate. This will
 ///     now be filled with inferred predicates.
-pub(super) fn infer_predicates<'tcx>(
-    tcx: TyCtxt<'tcx>,
-) -> FxHashMap<DefId, ty::EarlyBinder<RequiredPredicates<'tcx>>> {
+pub(super) fn infer_predicates(
+    tcx: TyCtxt<'_>,
+) -> FxHashMap<DefId, ty::EarlyBinder<RequiredPredicates<'_>>> {
     debug!("infer_predicates");
 
     let mut explicit_map = ExplicitPredicatesMap::new();

compiler/rustc_hir_typeck/src/coercion.rs

@@ -118,7 +118,7 @@ fn identity(_: Ty<'_>) -> Vec<Adjustment<'_>> {
     vec![]
 }
 
-fn simple<'tcx>(kind: Adjust<'tcx>) -> impl FnOnce(Ty<'tcx>) -> Vec<Adjustment<'tcx>> {
+fn simple<'tcx>(kind: Adjust<'tcx>) -> impl FnOnce(Ty<'tcx>) -> Vec<Adjustment<'_>> {
     move |target| vec![Adjustment { kind, target }]
 }
 

compiler/rustc_hir_typeck/src/expr_use_visitor.rs

@@ -756,8 +756,8 @@ impl<'a, 'tcx> ExprUseVisitor<'a, 'tcx> {
     /// - When reporting the Place back to the Delegate, ensure that the UpvarId uses the enclosing
     /// closure as the DefId.
     fn walk_captures(&mut self, closure_expr: &hir::Closure<'_>) {
-        fn upvar_is_local_variable<'tcx>(
-            upvars: Option<&'tcx FxIndexMap<hir::HirId, hir::Upvar>>,
+        fn upvar_is_local_variable(
+            upvars: Option<&FxIndexMap<hir::HirId, hir::Upvar>>,
             upvar_id: hir::HirId,
             body_owner_is_closure: bool,
         ) -> bool {

compiler/rustc_hir_typeck/src/generator_interior/drop_ranges/mod.rs

@@ -79,7 +79,7 @@ pub fn compute_drop_ranges<'a, 'tcx>(
 /// result of `foo`. On the other hand, if `place` points to `x` then `f` will
 /// be called both on the `ExprKind::Path` node that represents the expression
 /// as well as the HirId of the local `x` itself.
-fn for_each_consumable<'tcx>(hir: Map<'tcx>, place: TrackedValue, mut f: impl FnMut(TrackedValue)) {
+fn for_each_consumable(hir: Map<'_>, place: TrackedValue, mut f: impl FnMut(TrackedValue)) {
     f(place);
     let node = hir.find(place.hir_id());
     if let Some(Node::Expr(expr)) = node {

compiler/rustc_hir_typeck/src/lib.rs

@@ -462,8 +462,8 @@ fn fatally_break_rust(sess: &Session) {
     ));
 }
 
-fn has_expected_num_generic_args<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn has_expected_num_generic_args(
+    tcx: TyCtxt<'_>,
     trait_did: Option<DefId>,
     expected: usize,
 ) -> bool {

compiler/rustc_hir_typeck/src/op.rs

@@ -904,7 +904,7 @@ enum Op {
 }
 
 /// Dereferences a single level of immutable referencing.
-fn deref_ty_if_possible<'tcx>(ty: Ty<'tcx>) -> Ty<'tcx> {
+fn deref_ty_if_possible(ty: Ty<'_>) -> Ty<'_> {
     match ty.kind() {
         ty::Ref(_, ty, hir::Mutability::Not) => *ty,
         _ => ty,

compiler/rustc_hir_typeck/src/upvar.rs

@@ -1675,7 +1675,7 @@ fn apply_capture_kind_on_capture_ty<'tcx>(
 }
 
 /// Returns the Span of where the value with the provided HirId would be dropped
-fn drop_location_span<'tcx>(tcx: TyCtxt<'tcx>, hir_id: hir::HirId) -> Span {
+fn drop_location_span(tcx: TyCtxt<'_>, hir_id: hir::HirId) -> Span {
     let owner_id = tcx.hir().get_enclosing_scope(hir_id).unwrap();
 
     let owner_node = tcx.hir().get(owner_id);
@@ -1843,10 +1843,10 @@ fn restrict_precision_for_drop_types<'a, 'tcx>(
 /// - No projections are applied to raw pointers, since these require unsafe blocks. We capture
 ///   them completely.
 /// - No projections are applied on top of Union ADTs, since these require unsafe blocks.
-fn restrict_precision_for_unsafe<'tcx>(
-    mut place: Place<'tcx>,
+fn restrict_precision_for_unsafe(
+    mut place: Place<'_>,
     mut curr_mode: ty::UpvarCapture,
-) -> (Place<'tcx>, ty::UpvarCapture) {
+) -> (Place<'_>, ty::UpvarCapture) {
     if place.base_ty.is_unsafe_ptr() {
         truncate_place_to_len_and_update_capture_kind(&mut place, &mut curr_mode, 0);
     }
@@ -1876,10 +1876,10 @@ fn restrict_precision_for_unsafe<'tcx>(
 /// - No Index projections are captured, since arrays are captured completely.
 /// - No unsafe block is required to capture `place`
 /// Returns the truncated place and updated capture mode.
-fn restrict_capture_precision<'tcx>(
-    place: Place<'tcx>,
+fn restrict_capture_precision(
+    place: Place<'_>,
     curr_mode: ty::UpvarCapture,
-) -> (Place<'tcx>, ty::UpvarCapture) {
+) -> (Place<'_>, ty::UpvarCapture) {
     let (mut place, mut curr_mode) = restrict_precision_for_unsafe(place, curr_mode);
 
     if place.projections.is_empty() {
@@ -1904,10 +1904,10 @@ fn restrict_capture_precision<'tcx>(
 }
 
 /// Truncate deref of any reference.
-fn adjust_for_move_closure<'tcx>(
-    mut place: Place<'tcx>,
+fn adjust_for_move_closure(
+    mut place: Place<'_>,
     mut kind: ty::UpvarCapture,
-) -> (Place<'tcx>, ty::UpvarCapture) {
+) -> (Place<'_>, ty::UpvarCapture) {
     let first_deref = place.projections.iter().position(|proj| proj.kind == ProjectionKind::Deref);
 
     if let Some(idx) = first_deref {
@@ -1919,10 +1919,10 @@ fn adjust_for_move_closure<'tcx>(
 
 /// Adjust closure capture just that if taking ownership of data, only move data
 /// from enclosing stack frame.
-fn adjust_for_non_move_closure<'tcx>(
-    mut place: Place<'tcx>,
+fn adjust_for_non_move_closure(
+    mut place: Place<'_>,
     mut kind: ty::UpvarCapture,
-) -> (Place<'tcx>, ty::UpvarCapture) {
+) -> (Place<'_>, ty::UpvarCapture) {
     let contains_deref =
         place.projections.iter().position(|proj| proj.kind == ProjectionKind::Deref);
 
@@ -2225,10 +2225,10 @@ fn determine_place_ancestry_relation<'tcx>(
 ///     // it is constrained to `'a`
 /// }
 /// ```
-fn truncate_capture_for_optimization<'tcx>(
-    mut place: Place<'tcx>,
+fn truncate_capture_for_optimization(
+    mut place: Place<'_>,
     mut curr_mode: ty::UpvarCapture,
-) -> (Place<'tcx>, ty::UpvarCapture) {
+) -> (Place<'_>, ty::UpvarCapture) {
     let is_shared_ref = |ty: Ty<'_>| matches!(ty.kind(), ty::Ref(.., hir::Mutability::Not));
 
     // Find the right-most deref (if any). All the projections that come after this

compiler/rustc_incremental/src/assert_dep_graph.rs

@@ -432,10 +432,7 @@ fn walk_between<'q>(
     }
 }
 
-fn filter_edges<'q>(
-    query: &'q DepGraphQuery,
-    nodes: &FxHashSet<DepKind>,
-) -> Vec<(DepKind, DepKind)> {
+fn filter_edges(query: &DepGraphQuery, nodes: &FxHashSet<DepKind>) -> Vec<(DepKind, DepKind)> {
     let uniq: FxHashSet<_> = query
         .edges()
         .into_iter()

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

@@ -2199,10 +2199,10 @@ impl<'tcx> TypeErrCtxt<'_, 'tcx> {
             );
         }
 
-        fn binding_suggestion<'tcx, S: fmt::Display>(
+        fn binding_suggestion<S: fmt::Display>(
             err: &mut Diagnostic,
             type_param_span: Option<(Span, bool)>,
-            bound_kind: GenericKind<'tcx>,
+            bound_kind: GenericKind<'_>,
             sub: S,
             add_lt_sugg: Option<(Span, String)>,
         ) {

compiler/rustc_lint/src/non_fmt_panic.rs

@@ -304,7 +304,7 @@ fn check_panic_str<'tcx>(
 
 /// Given the span of `some_macro!(args);`, gives the span of `(` and `)`,
 /// and the type of (opening) delimiter used.
-fn find_delimiters<'tcx>(cx: &LateContext<'tcx>, span: Span) -> Option<(Span, Span, char)> {
+fn find_delimiters(cx: &LateContext<'_>, span: Span) -> Option<(Span, Span, char)> {
     let snippet = cx.sess().parse_sess.source_map().span_to_snippet(span).ok()?;
     let (open, open_ch) = snippet.char_indices().find(|&(_, c)| "([{".contains(c))?;
     let close = snippet.rfind(|c| ")]}".contains(c))?;

compiler/rustc_lint_defs/src/builtin.rs

@@ -1405,7 +1405,7 @@ declare_lint! {
     /// struct S;
     ///
     /// impl S {
-    ///     fn late<'a, 'b>(self, _: &'a u8, _: &'b u8) {}
+    ///     fn late(self, _: &u8, _: &u8) {}
     /// }
     ///
     /// fn main() {

compiler/rustc_macros/src/diagnostics/subdiagnostic.rs

@@ -29,7 +29,7 @@ impl SubdiagnosticDeriveBuilder {
         Self { diag, f }
     }
 
-    pub(crate) fn into_tokens<'a>(self, mut structure: Structure<'a>) -> TokenStream {
+    pub(crate) fn into_tokens(self, mut structure: Structure<'_>) -> TokenStream {
         let implementation = {
             let ast = structure.ast();
             let span = ast.span().unwrap();

compiler/rustc_macros/src/diagnostics/utils.rs

@@ -385,7 +385,7 @@ impl quote::ToTokens for Applicability {
 
 /// Build the mapping of field names to fields. This allows attributes to peek values from
 /// other fields.
-pub(super) fn build_field_mapping<'v>(variant: &VariantInfo<'v>) -> HashMap<String, TokenStream> {
+pub(super) fn build_field_mapping(variant: &VariantInfo<'_>) -> HashMap<String, TokenStream> {
     let mut fields_map = FieldMap::new();
     for binding in variant.bindings() {
         if let Some(ident) = &binding.ast().ident {

compiler/rustc_metadata/src/creader.rs

@@ -520,8 +520,8 @@ impl<'a> CrateLoader<'a> {
         }))
     }
 
-    fn resolve_crate<'b>(
-        &'b mut self,
+    fn resolve_crate(
+        &mut self,
         name: Symbol,
         span: Span,
         dep_kind: CrateDepKind,

compiler/rustc_metadata/src/rmeta/encoder.rs

@@ -1093,7 +1093,7 @@ fn should_encode_const(def_kind: DefKind) -> bool {
     }
 }
 
-fn should_encode_trait_impl_trait_tys<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> bool {
+fn should_encode_trait_impl_trait_tys(tcx: TyCtxt<'_>, def_id: DefId) -> bool {
     if tcx.def_kind(def_id) != DefKind::AssocFn {
         return false;
     }

compiler/rustc_middle/src/dep_graph/dep_node.rs

@@ -175,7 +175,7 @@ impl DepNodeExt for DepNode {
     /// DepNode. Condition (2) might not be fulfilled if a DepNode
     /// refers to something from the previous compilation session that
     /// has been removed.
-    fn extract_def_id<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Option<DefId> {
+    fn extract_def_id(&self, tcx: TyCtxt<'_>) -> Option<DefId> {
         if tcx.fingerprint_style(self.kind) == FingerprintStyle::DefPathHash {
             Some(tcx.def_path_hash_to_def_id(DefPathHash(self.hash.into()), &mut || {
                 panic!("Failed to extract DefId: {:?} {}", self.kind, self.hash)

compiler/rustc_middle/src/hir/map/mod.rs

@@ -18,7 +18,7 @@ use rustc_span::Span;
 use rustc_target::spec::abi::Abi;
 
 #[inline]
-pub fn associated_body<'hir>(node: Node<'hir>) -> Option<BodyId> {
+pub fn associated_body(node: Node<'_>) -> Option<BodyId> {
     match node {
         Node::Item(Item {
             kind: ItemKind::Const(_, body) | ItemKind::Static(.., body) | ItemKind::Fn(.., body),
@@ -41,7 +41,7 @@ pub fn associated_body<'hir>(node: Node<'hir>) -> Option<BodyId> {
     }
 }
 
-fn is_body_owner<'hir>(node: Node<'hir>, hir_id: HirId) -> bool {
+fn is_body_owner(node: Node<'_>, hir_id: HirId) -> bool {
     match associated_body(node) {
         Some(b) => b.hir_id == hir_id,
         None => false,

compiler/rustc_middle/src/middle/stability.rs

@@ -223,8 +223,8 @@ pub fn deprecation_message_and_lint(
     )
 }
 
-pub fn early_report_deprecation<'a>(
-    lint_buffer: &'a mut LintBuffer,
+pub fn early_report_deprecation(
+    lint_buffer: &mut LintBuffer,
     message: &str,
     suggestion: Option<Symbol>,
     lint: &'static Lint,

compiler/rustc_middle/src/mir/mod.rs

@@ -1767,9 +1767,9 @@ impl SourceScope {
     /// Finds the original HirId this MIR item came from.
     /// This is necessary after MIR optimizations, as otherwise we get a HirId
     /// from the function that was inlined instead of the function call site.
-    pub fn lint_root<'tcx>(
+    pub fn lint_root(
         self,
-        source_scopes: &IndexVec<SourceScope, SourceScopeData<'tcx>>,
+        source_scopes: &IndexVec<SourceScope, SourceScopeData<'_>>,
     ) -> Option<HirId> {
         let mut data = &source_scopes[self];
         // FIXME(oli-obk): we should be able to just walk the `inlined_parent_scope`, but it

compiler/rustc_middle/src/mir/pretty.rs

@@ -88,7 +88,7 @@ pub fn dump_mir<'tcx, F>(
     dump_matched_mir_node(tcx, pass_num, pass_name, disambiguator, body, extra_data);
 }
 
-pub fn dump_enabled<'tcx>(tcx: TyCtxt<'tcx>, pass_name: &str, def_id: DefId) -> bool {
+pub fn dump_enabled(tcx: TyCtxt<'_>, pass_name: &str, def_id: DefId) -> bool {
     let Some(ref filters) = tcx.sess.opts.unstable_opts.dump_mir else {
         return false;
     };
@@ -421,7 +421,7 @@ impl<'tcx> ExtraComments<'tcx> {
     }
 }
 
-fn use_verbose<'tcx>(ty: Ty<'tcx>, fn_def: bool) -> bool {
+fn use_verbose(ty: Ty<'_>, fn_def: bool) -> bool {
     match *ty.kind() {
         ty::Int(_) | ty::Uint(_) | ty::Bool | ty::Char | ty::Float(_) => false,
         // Unit type

compiler/rustc_middle/src/mir/spanview.rs

@@ -230,7 +230,7 @@ where
 }
 
 /// Format a string showing the start line and column, and end line and column within a file.
-pub fn source_range_no_file<'tcx>(tcx: TyCtxt<'tcx>, span: Span) -> String {
+pub fn source_range_no_file(tcx: TyCtxt<'_>, span: Span) -> String {
     let source_map = tcx.sess.source_map();
     let start = source_map.lookup_char_pos(span.lo());
     let end = source_map.lookup_char_pos(span.hi());
@@ -322,7 +322,7 @@ fn block_span_viewable<'tcx>(
     Some(SpanViewable { bb, span, id, tooltip })
 }
 
-fn compute_block_span<'tcx>(data: &BasicBlockData<'tcx>, body_span: Span) -> Span {
+fn compute_block_span(data: &BasicBlockData<'_>, body_span: Span) -> Span {
     let mut span = data.terminator().source_info.span;
     for statement_span in data.statements.iter().map(|statement| statement.source_info.span) {
         // Only combine Spans from the root context, and within the function's body_span.
@@ -522,12 +522,7 @@ where
 }
 
 #[inline(always)]
-fn write_coverage_gap<'tcx, W>(
-    tcx: TyCtxt<'tcx>,
-    lo: BytePos,
-    hi: BytePos,
-    w: &mut W,
-) -> io::Result<()>
+fn write_coverage_gap<W>(tcx: TyCtxt<'_>, lo: BytePos, hi: BytePos, w: &mut W) -> io::Result<()>
 where
     W: Write,
 {
@@ -582,8 +577,8 @@ where
     Ok(())
 }
 
-fn make_html_snippet<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn make_html_snippet(
+    tcx: TyCtxt<'_>,
     span: Span,
     some_viewable: Option<&SpanViewable>,
 ) -> Option<String> {
@@ -664,7 +659,7 @@ fn trim_span_hi(span: Span, to_pos: BytePos) -> Span {
     if to_pos >= span.hi() { span } else { span.with_hi(cmp::max(span.lo(), to_pos)) }
 }
 
-fn fn_span<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Span {
+fn fn_span(tcx: TyCtxt<'_>, def_id: DefId) -> Span {
     let fn_decl_span = tcx.def_span(def_id);
     if let Some(body_span) = hir_body(tcx, def_id).map(|hir_body| hir_body.value.span) {
         if fn_decl_span.eq_ctxt(body_span) { fn_decl_span.to(body_span) } else { body_span }
@@ -673,7 +668,7 @@ fn fn_span<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Span {
     }
 }
 
-fn hir_body<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Option<&'tcx rustc_hir::Body<'tcx>> {
+fn hir_body(tcx: TyCtxt<'_>, def_id: DefId) -> Option<&rustc_hir::Body<'_>> {
     let hir_node = tcx.hir().get_if_local(def_id).expect("expected DefId is local");
     hir::map::associated_body(hir_node).map(|fn_body_id| tcx.hir().body(fn_body_id))
 }

compiler/rustc_middle/src/mir/traversal.rs

@@ -302,7 +302,7 @@ pub fn reachable<'a, 'tcx>(
 }
 
 /// Returns a `BitSet` containing all basic blocks reachable from the `START_BLOCK`.
-pub fn reachable_as_bitset<'tcx>(body: &Body<'tcx>) -> BitSet<BasicBlock> {
+pub fn reachable_as_bitset(body: &Body<'_>) -> BitSet<BasicBlock> {
     let mut iter = preorder(body);
     (&mut iter).for_each(drop);
     iter.visited

compiler/rustc_middle/src/traits/chalk.rs

@@ -210,7 +210,7 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         Box::new(chalk_ir::TyData { kind: ty, flags: flags })
     }
 
-    fn ty_data<'a>(self, ty: &'a Self::InternedType) -> &'a chalk_ir::TyData<Self> {
+    fn ty_data(self, ty: &Self::InternedType) -> &chalk_ir::TyData<Self> {
         ty
     }
 
@@ -218,10 +218,7 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         Box::new(lifetime)
     }
 
-    fn lifetime_data<'a>(
-        self,
-        lifetime: &'a Self::InternedLifetime,
-    ) -> &'a chalk_ir::LifetimeData<Self> {
+    fn lifetime_data(self, lifetime: &Self::InternedLifetime) -> &chalk_ir::LifetimeData<Self> {
         &lifetime
     }
 
@@ -229,7 +226,7 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         Box::new(constant)
     }
 
-    fn const_data<'a>(self, constant: &'a Self::InternedConst) -> &'a chalk_ir::ConstData<Self> {
+    fn const_data(self, constant: &Self::InternedConst) -> &chalk_ir::ConstData<Self> {
         &constant
     }
 
@@ -246,10 +243,7 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         Box::new(data)
     }
 
-    fn generic_arg_data<'a>(
-        self,
-        data: &'a Self::InternedGenericArg,
-    ) -> &'a chalk_ir::GenericArgData<Self> {
+    fn generic_arg_data(self, data: &Self::InternedGenericArg) -> &chalk_ir::GenericArgData<Self> {
         &data
     }
 
@@ -257,7 +251,7 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         Box::new(goal)
     }
 
-    fn goal_data<'a>(self, goal: &'a Self::InternedGoal) -> &'a chalk_ir::GoalData<Self> {
+    fn goal_data(self, goal: &Self::InternedGoal) -> &chalk_ir::GoalData<Self> {
         &goal
     }
 
@@ -268,7 +262,7 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         data.into_iter().collect::<Result<Vec<_>, _>>()
     }
 
-    fn goals_data<'a>(self, goals: &'a Self::InternedGoals) -> &'a [chalk_ir::Goal<Self>] {
+    fn goals_data(self, goals: &Self::InternedGoals) -> &[chalk_ir::Goal<Self>] {
         goals
     }
 
@@ -279,10 +273,10 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         data.into_iter().collect::<Result<Vec<_>, _>>()
     }
 
-    fn substitution_data<'a>(
+    fn substitution_data(
         self,
-        substitution: &'a Self::InternedSubstitution,
-    ) -> &'a [chalk_ir::GenericArg<Self>] {
+        substitution: &Self::InternedSubstitution,
+    ) -> &[chalk_ir::GenericArg<Self>] {
         substitution
     }
 
@@ -293,10 +287,10 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         Box::new(data)
     }
 
-    fn program_clause_data<'a>(
+    fn program_clause_data(
         self,
-        clause: &'a Self::InternedProgramClause,
-    ) -> &'a chalk_ir::ProgramClauseData<Self> {
+        clause: &Self::InternedProgramClause,
+    ) -> &chalk_ir::ProgramClauseData<Self> {
         &clause
     }
 
@@ -307,10 +301,10 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         data.into_iter().collect::<Result<Vec<_>, _>>()
     }
 
-    fn program_clauses_data<'a>(
+    fn program_clauses_data(
         self,
-        clauses: &'a Self::InternedProgramClauses,
-    ) -> &'a [chalk_ir::ProgramClause<Self>] {
+        clauses: &Self::InternedProgramClauses,
+    ) -> &[chalk_ir::ProgramClause<Self>] {
         clauses
     }
 
@@ -321,10 +315,10 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         data.into_iter().collect::<Result<Vec<_>, _>>()
     }
 
-    fn quantified_where_clauses_data<'a>(
+    fn quantified_where_clauses_data(
         self,
-        clauses: &'a Self::InternedQuantifiedWhereClauses,
-    ) -> &'a [chalk_ir::QuantifiedWhereClause<Self>] {
+        clauses: &Self::InternedQuantifiedWhereClauses,
+    ) -> &[chalk_ir::QuantifiedWhereClause<Self>] {
         clauses
     }
 
@@ -335,10 +329,10 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         data.into_iter().collect::<Result<Vec<_>, _>>()
     }
 
-    fn variable_kinds_data<'a>(
+    fn variable_kinds_data(
         self,
-        parameter_kinds: &'a Self::InternedVariableKinds,
-    ) -> &'a [chalk_ir::VariableKind<Self>] {
+        parameter_kinds: &Self::InternedVariableKinds,
+    ) -> &[chalk_ir::VariableKind<Self>] {
         parameter_kinds
     }
 
@@ -349,10 +343,10 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         data.into_iter().collect::<Result<Vec<_>, _>>()
     }
 
-    fn canonical_var_kinds_data<'a>(
+    fn canonical_var_kinds_data(
         self,
-        canonical_var_kinds: &'a Self::InternedCanonicalVarKinds,
-    ) -> &'a [chalk_ir::CanonicalVarKind<Self>] {
+        canonical_var_kinds: &Self::InternedCanonicalVarKinds,
+    ) -> &[chalk_ir::CanonicalVarKind<Self>] {
         canonical_var_kinds
     }
 
@@ -363,10 +357,10 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         data.into_iter().collect::<Result<Vec<_>, _>>()
     }
 
-    fn constraints_data<'a>(
+    fn constraints_data(
         self,
-        constraints: &'a Self::InternedConstraints,
-    ) -> &'a [chalk_ir::InEnvironment<chalk_ir::Constraint<Self>>] {
+        constraints: &Self::InternedConstraints,
+    ) -> &[chalk_ir::InEnvironment<chalk_ir::Constraint<Self>>] {
         constraints
     }
 
@@ -377,10 +371,7 @@ impl<'tcx> chalk_ir::interner::Interner for RustInterner<'tcx> {
         data.into_iter().collect::<Result<Vec<_>, _>>()
     }
 
-    fn variances_data<'a>(
-        self,
-        variances: &'a Self::InternedVariances,
-    ) -> &'a [chalk_ir::Variance] {
+    fn variances_data(self, variances: &Self::InternedVariances) -> &[chalk_ir::Variance] {
         variances
     }
 }

compiler/rustc_middle/src/traits/specialization_graph.rs

@@ -60,7 +60,7 @@ pub enum OverlapMode {
 }
 
 impl OverlapMode {
-    pub fn get<'tcx>(tcx: TyCtxt<'tcx>, trait_id: DefId) -> OverlapMode {
+    pub fn get(tcx: TyCtxt<'_>, trait_id: DefId) -> OverlapMode {
         let with_negative_coherence = tcx.features().with_negative_coherence;
         let strict_coherence = tcx.has_attr(trait_id, sym::rustc_strict_coherence);
 
@@ -253,11 +253,11 @@ impl<'tcx> Ancestors<'tcx> {
 ///
 /// Returns `Err` if an error was reported while building the specialization
 /// graph.
-pub fn ancestors<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub fn ancestors(
+    tcx: TyCtxt<'_>,
     trait_def_id: DefId,
     start_from_impl: DefId,
-) -> Result<Ancestors<'tcx>, ErrorGuaranteed> {
+) -> Result<Ancestors<'_>, ErrorGuaranteed> {
     let specialization_graph = tcx.specialization_graph_of(trait_def_id);
 
     if let Some(reported) = specialization_graph.has_errored {

compiler/rustc_middle/src/ty/closure.rs

@@ -238,10 +238,7 @@ impl<'tcx> CapturedPlace<'tcx> {
     }
 }
 
-fn symbols_for_closure_captures<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    def_id: (LocalDefId, LocalDefId),
-) -> Vec<Symbol> {
+fn symbols_for_closure_captures(tcx: TyCtxt<'_>, def_id: (LocalDefId, LocalDefId)) -> Vec<Symbol> {
     let typeck_results = tcx.typeck(def_id.0);
     let captures = typeck_results.closure_min_captures_flattened(def_id.1);
     captures.into_iter().map(|captured_place| captured_place.to_symbol(tcx)).collect()

compiler/rustc_middle/src/ty/consts.rs

@@ -239,7 +239,7 @@ impl<'tcx> Const<'tcx> {
     }
 }
 
-pub fn const_param_default<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Const<'tcx> {
+pub fn const_param_default(tcx: TyCtxt<'_>, def_id: DefId) -> Const<'_> {
     let default_def_id = match tcx.hir().get_by_def_id(def_id.expect_local()) {
         hir::Node::GenericParam(hir::GenericParam {
             kind: hir::GenericParamKind::Const { default: Some(ac), .. },

compiler/rustc_middle/src/ty/consts/int.rs

@@ -232,7 +232,7 @@ impl ScalarInt {
     }
 
     #[inline]
-    pub fn try_to_machine_usize<'tcx>(&self, tcx: TyCtxt<'tcx>) -> Result<u64, Size> {
+    pub fn try_to_machine_usize(&self, tcx: TyCtxt<'_>) -> Result<u64, Size> {
         Ok(self.to_bits(tcx.data_layout.pointer_size)? as u64)
     }
 

compiler/rustc_middle/src/ty/context.rs

@@ -1518,7 +1518,7 @@ impl<'tcx, T: 'tcx + ?Sized> IntoPointer for InternedInSet<'tcx, T> {
 
 #[allow(rustc::usage_of_ty_tykind)]
 impl<'tcx, T> Borrow<T> for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
-    fn borrow<'a>(&'a self) -> &'a T {
+    fn borrow(&self) -> &T {
         &self.0.internee
     }
 }
@@ -1541,7 +1541,7 @@ impl<'tcx, T: Hash> Hash for InternedInSet<'tcx, WithCachedTypeInfo<T>> {
 }
 
 impl<'tcx, T> Borrow<[T]> for InternedInSet<'tcx, List<T>> {
-    fn borrow<'a>(&'a self) -> &'a [T] {
+    fn borrow(&self) -> &[T] {
         &self.0[..]
     }
 }

compiler/rustc_middle/src/ty/flags.rs

@@ -22,7 +22,7 @@ impl FlagComputation {
         result
     }
 
-    pub fn for_predicate<'tcx>(binder: ty::Binder<'tcx, ty::PredicateKind<'_>>) -> FlagComputation {
+    pub fn for_predicate(binder: ty::Binder<'_, ty::PredicateKind<'_>>) -> FlagComputation {
         let mut result = FlagComputation::new();
         result.add_predicate(binder);
         result

compiler/rustc_middle/src/ty/layout.rs

@@ -993,7 +993,7 @@ where
 /// might (from a foreign exception or similar).
 #[inline]
 #[tracing::instrument(level = "debug", skip(tcx))]
-pub fn fn_can_unwind<'tcx>(tcx: TyCtxt<'tcx>, fn_def_id: Option<DefId>, abi: SpecAbi) -> bool {
+pub fn fn_can_unwind(tcx: TyCtxt<'_>, fn_def_id: Option<DefId>, abi: SpecAbi) -> bool {
     if let Some(did) = fn_def_id {
         // Special attribute for functions which can't unwind.
         if tcx.codegen_fn_attrs(did).flags.contains(CodegenFnAttrFlags::NEVER_UNWIND) {

compiler/rustc_middle/src/ty/util.rs

@@ -1248,7 +1248,7 @@ pub fn needs_drop_components<'tcx>(
     }
 }
 
-pub fn is_trivially_const_drop<'tcx>(ty: Ty<'tcx>) -> bool {
+pub fn is_trivially_const_drop(ty: Ty<'_>) -> bool {
     match *ty.kind() {
         ty::Bool
         | ty::Char

compiler/rustc_mir_build/src/build/expr/as_place.rs

@@ -81,8 +81,8 @@ pub(in crate::build) struct PlaceBuilder<'tcx> {
 /// ProjectionElems `Downcast`, `ConstantIndex`, `Index`, or `Subslice` because those will never be
 /// part of a path that is captured by a closure. We stop applying projections once we see the first
 /// projection that isn't captured by a closure.
-fn convert_to_hir_projections_and_truncate_for_capture<'tcx>(
-    mir_projections: &[PlaceElem<'tcx>],
+fn convert_to_hir_projections_and_truncate_for_capture(
+    mir_projections: &[PlaceElem<'_>],
 ) -> Vec<HirProjectionKind> {
     let mut hir_projections = Vec::new();
     let mut variant = None;

compiler/rustc_mir_build/src/build/mod.rs

@@ -28,10 +28,10 @@ use rustc_target::spec::abi::Abi;
 
 use super::lints;
 
-pub(crate) fn mir_built<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub(crate) fn mir_built(
+    tcx: TyCtxt<'_>,
     def: ty::WithOptConstParam<LocalDefId>,
-) -> &'tcx rustc_data_structures::steal::Steal<Body<'tcx>> {
+) -> &rustc_data_structures::steal::Steal<Body<'_>> {
     if let Some(def) = def.try_upgrade(tcx) {
         return tcx.mir_built(def);
     }
@@ -625,12 +625,12 @@ fn construct_const<'a, 'tcx>(
 ///
 /// This is required because we may still want to run MIR passes on an item
 /// with type errors, but normal MIR construction can't handle that in general.
-fn construct_error<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn construct_error(
+    tcx: TyCtxt<'_>,
     def: LocalDefId,
     body_owner_kind: hir::BodyOwnerKind,
     err: ErrorGuaranteed,
-) -> Body<'tcx> {
+) -> Body<'_> {
     let span = tcx.def_span(def);
     let hir_id = tcx.hir().local_def_id_to_hir_id(def);
     let generator_kind = tcx.generator_kind(def);

compiler/rustc_mir_build/src/check_unsafety.rs

@@ -703,7 +703,7 @@ impl UnsafeOpKind {
     }
 }
 
-pub fn check_unsafety<'tcx>(tcx: TyCtxt<'tcx>, def: ty::WithOptConstParam<LocalDefId>) {
+pub fn check_unsafety(tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>) {
     // THIR unsafeck is gated under `-Z thir-unsafeck`
     if !tcx.sess.opts.unstable_opts.thir_unsafeck {
         return;
@@ -749,7 +749,7 @@ pub fn check_unsafety<'tcx>(tcx: TyCtxt<'tcx>, def: ty::WithOptConstParam<LocalD
     visitor.visit_expr(&thir[expr]);
 }
 
-pub(crate) fn thir_check_unsafety<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) {
+pub(crate) fn thir_check_unsafety(tcx: TyCtxt<'_>, def_id: LocalDefId) {
     if let Some(def) = ty::WithOptConstParam::try_lookup(def_id, tcx) {
         tcx.thir_check_unsafety_for_const_arg(def)
     } else {
@@ -757,8 +757,8 @@ pub(crate) fn thir_check_unsafety<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) {
     }
 }
 
-pub(crate) fn thir_check_unsafety_for_const_arg<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub(crate) fn thir_check_unsafety_for_const_arg(
+    tcx: TyCtxt<'_>,
     (did, param_did): (LocalDefId, DefId),
 ) {
     check_unsafety(tcx, ty::WithOptConstParam { did, const_param_did: Some(param_did) })

compiler/rustc_mir_build/src/thir/cx/mod.rs

@@ -18,10 +18,10 @@ use rustc_middle::thir::*;
 use rustc_middle::ty::{self, RvalueScopes, TyCtxt};
 use rustc_span::Span;
 
-pub(crate) fn thir_body<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub(crate) fn thir_body(
+    tcx: TyCtxt<'_>,
     owner_def: ty::WithOptConstParam<LocalDefId>,
-) -> Result<(&'tcx Steal<Thir<'tcx>>, ExprId), ErrorGuaranteed> {
+) -> Result<(&Steal<Thir<'_>>, ExprId), ErrorGuaranteed> {
     let hir = tcx.hir();
     let body = hir.body(hir.body_owned_by(owner_def.did));
     let mut cx = Cx::new(tcx, owner_def);
@@ -52,10 +52,7 @@ pub(crate) fn thir_body<'tcx>(
     Ok((tcx.alloc_steal_thir(cx.thir), expr))
 }
 
-pub(crate) fn thir_tree<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    owner_def: ty::WithOptConstParam<LocalDefId>,
-) -> String {
+pub(crate) fn thir_tree(tcx: TyCtxt<'_>, owner_def: ty::WithOptConstParam<LocalDefId>) -> String {
     match thir_body(tcx, owner_def) {
         Ok((thir, _)) => format!("{:#?}", thir.steal()),
         Err(_) => "error".into(),

compiler/rustc_mir_build/src/thir/pattern/const_to_pat.rs

@@ -70,7 +70,7 @@ mod fallback_to_const_ref {
     /// hoops to get a reference to the value.
     pub(super) struct FallbackToConstRef(());
 
-    pub(super) fn fallback_to_const_ref<'tcx>(c2p: &super::ConstToPat<'tcx>) -> FallbackToConstRef {
+    pub(super) fn fallback_to_const_ref(c2p: &super::ConstToPat<'_>) -> FallbackToConstRef {
         assert!(c2p.behind_reference.get());
         FallbackToConstRef(())
     }

compiler/rustc_mir_build/src/thir/pattern/deconstruct_pat.rs

@@ -404,7 +404,7 @@ impl SplitIntRange {
     }
 
     /// Iterate over the contained ranges.
-    fn iter<'a>(&'a self) -> impl Iterator<Item = IntRange> + Captures<'a> {
+    fn iter(&self) -> impl Iterator<Item = IntRange> + Captures<'_> {
         use IntBorder::*;
 
         let self_range = Self::to_borders(self.range.clone());
@@ -612,7 +612,7 @@ impl SplitVarLenSlice {
     }
 
     /// Iterate over the partition of this slice.
-    fn iter<'a>(&'a self) -> impl Iterator<Item = Slice> + Captures<'a> {
+    fn iter(&self) -> impl Iterator<Item = Slice> + Captures<'_> {
         let smaller_lengths = match self.array_len {
             // The only admissible fixed-length slice is one of the array size. Whether `max_slice`
             // is fixed-length or variable-length, it will be the only relevant slice to output

compiler/rustc_mir_dataflow/src/impls/liveness.rs

@@ -149,7 +149,7 @@ enum DefUse {
 }
 
 impl DefUse {
-    fn apply<'tcx>(trans: &mut impl GenKill<Local>, place: Place<'tcx>, context: PlaceContext) {
+    fn apply(trans: &mut impl GenKill<Local>, place: Place<'_>, context: PlaceContext) {
         match DefUse::for_place(place, context) {
             Some(DefUse::Def) => trans.kill(place.local),
             Some(DefUse::Use) => trans.gen(place.local),
@@ -157,7 +157,7 @@ impl DefUse {
         }
     }
 
-    fn for_place<'tcx>(place: Place<'tcx>, context: PlaceContext) -> Option<DefUse> {
+    fn for_place(place: Place<'_>, context: PlaceContext) -> Option<DefUse> {
         match context {
             PlaceContext::NonUse(_) => None,
 

compiler/rustc_mir_dataflow/src/value_analysis.rs

@@ -823,7 +823,7 @@ fn iter_fields<'tcx>(
 }
 
 /// Returns all locals with projections that have their reference or address taken.
-fn excluded_locals<'tcx>(body: &Body<'tcx>) -> IndexVec<Local, bool> {
+fn excluded_locals(body: &Body<'_>) -> IndexVec<Local, bool> {
     struct Collector {
         result: IndexVec<Local, bool>,
     }

compiler/rustc_mir_transform/src/check_unsafety.rs

@@ -490,10 +490,10 @@ fn check_unused_unsafe(
     unused_unsafes
 }
 
-fn unsafety_check_result<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn unsafety_check_result(
+    tcx: TyCtxt<'_>,
     def: ty::WithOptConstParam<LocalDefId>,
-) -> &'tcx UnsafetyCheckResult {
+) -> &UnsafetyCheckResult {
     debug!("unsafety_violations({:?})", def);
 
     // N.B., this borrow is valid because all the consumers of

compiler/rustc_mir_transform/src/coverage/mod.rs

@@ -533,10 +533,10 @@ fn make_code_region(
     }
 }
 
-fn fn_sig_and_body<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn fn_sig_and_body(
+    tcx: TyCtxt<'_>,
     def_id: DefId,
-) -> (Option<&'tcx rustc_hir::FnSig<'tcx>>, &'tcx rustc_hir::Body<'tcx>) {
+) -> (Option<&rustc_hir::FnSig<'_>>, &rustc_hir::Body<'_>) {
     // FIXME(#79625): Consider improving MIR to provide the information needed, to avoid going back
     // to HIR for it.
     let hir_node = tcx.hir().get_if_local(def_id).expect("expected DefId is local");

compiler/rustc_mir_transform/src/coverage/query.rs

@@ -136,7 +136,7 @@ fn coverageinfo<'tcx>(tcx: TyCtxt<'tcx>, instance_def: ty::InstanceDef<'tcx>) ->
     coverage_visitor.info
 }
 
-fn covered_code_regions<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> Vec<&'tcx CodeRegion> {
+fn covered_code_regions(tcx: TyCtxt<'_>, def_id: DefId) -> Vec<&CodeRegion> {
     let body = mir_body(tcx, def_id);
     body.basic_blocks
         .iter()
@@ -163,7 +163,7 @@ fn is_inlined(body: &Body<'_>, statement: &Statement<'_>) -> bool {
 /// This function ensures we obtain the correct MIR for the given item irrespective of
 /// whether that means const mir or runtime mir. For `const fn` this opts for runtime
 /// mir.
-fn mir_body<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx mir::Body<'tcx> {
+fn mir_body(tcx: TyCtxt<'_>, def_id: DefId) -> &mir::Body<'_> {
     let id = ty::WithOptConstParam::unknown(def_id);
     let def = ty::InstanceDef::Item(id);
     tcx.instance_mir(def)

compiler/rustc_mir_transform/src/coverage/tests.rs

@@ -169,7 +169,7 @@ impl<'tcx> MockBlocks<'tcx> {
     }
 }
 
-fn debug_basic_blocks<'tcx>(mir_body: &Body<'tcx>) -> String {
+fn debug_basic_blocks(mir_body: &Body) -> String {
     format!(
         "{:?}",
         mir_body

compiler/rustc_mir_transform/src/deduce_param_attrs.rs

@@ -129,7 +129,7 @@ impl<'tcx> Visitor<'tcx> for DeduceReadOnly {
 }
 
 /// Returns true if values of a given type will never be passed indirectly, regardless of ABI.
-fn type_will_always_be_passed_directly<'tcx>(ty: Ty<'tcx>) -> bool {
+fn type_will_always_be_passed_directly(ty: Ty<'_>) -> bool {
     matches!(
         ty.kind(),
         ty::Bool

compiler/rustc_mir_transform/src/dest_prop.rs

@@ -658,7 +658,7 @@ impl WriteInfo {
         }
     }
 
-    fn add_place<'tcx>(&mut self, place: Place<'tcx>) {
+    fn add_place(&mut self, place: Place<'_>) {
         self.writes.push(place.local);
     }
 

compiler/rustc_mir_transform/src/lib.rs

@@ -266,10 +266,7 @@ fn mir_const_qualif(tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>) ->
 /// Make MIR ready for const evaluation. This is run on all MIR, not just on consts!
 /// FIXME(oli-obk): it's unclear whether we still need this phase (and its corresponding query).
 /// We used to have this for pre-miri MIR based const eval.
-fn mir_const<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    def: ty::WithOptConstParam<LocalDefId>,
-) -> &'tcx Steal<Body<'tcx>> {
+fn mir_const(tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>) -> &Steal<Body<'_>> {
     if let Some(def) = def.try_upgrade(tcx) {
         return tcx.mir_const(def);
     }
@@ -308,10 +305,10 @@ fn mir_const<'tcx>(
 }
 
 /// Compute the main MIR body and the list of MIR bodies of the promoteds.
-fn mir_promoted<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn mir_promoted(
+    tcx: TyCtxt<'_>,
     def: ty::WithOptConstParam<LocalDefId>,
-) -> (&'tcx Steal<Body<'tcx>>, &'tcx Steal<IndexVec<Promoted, Body<'tcx>>>) {
+) -> (&Steal<Body<'_>>, &Steal<IndexVec<Promoted, Body<'_>>>) {
     if let Some(def) = def.try_upgrade(tcx) {
         return tcx.mir_promoted(def);
     }
@@ -350,7 +347,7 @@ fn mir_promoted<'tcx>(
 }
 
 /// Compute the MIR that is used during CTFE (and thus has no optimizations run on it)
-fn mir_for_ctfe<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx Body<'tcx> {
+fn mir_for_ctfe(tcx: TyCtxt<'_>, def_id: DefId) -> &Body<'_> {
     let did = def_id.expect_local();
     if let Some(def) = ty::WithOptConstParam::try_lookup(did, tcx) {
         tcx.mir_for_ctfe_of_const_arg(def)
@@ -364,10 +361,7 @@ fn mir_for_ctfe<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> &'tcx Body<'tcx> {
 /// we'd get cycle errors with `mir_for_ctfe`, because typeck would need to typeck
 /// the const parameter while type checking the main body, which in turn would try
 /// to type check the main body again.
-fn mir_for_ctfe_of_const_arg<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    (did, param_did): (LocalDefId, DefId),
-) -> &'tcx Body<'tcx> {
+fn mir_for_ctfe_of_const_arg(tcx: TyCtxt<'_>, (did, param_did): (LocalDefId, DefId)) -> &Body<'_> {
     tcx.arena.alloc(inner_mir_for_ctfe(
         tcx,
         ty::WithOptConstParam { did, const_param_did: Some(param_did) },
@@ -424,10 +418,10 @@ fn inner_mir_for_ctfe(tcx: TyCtxt<'_>, def: ty::WithOptConstParam<LocalDefId>) -
 /// Obtain just the main MIR (no promoteds) and run some cleanups on it. This also runs
 /// mir borrowck *before* doing so in order to ensure that borrowck can be run and doesn't
 /// end up missing the source MIR due to stealing happening.
-fn mir_drops_elaborated_and_const_checked<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn mir_drops_elaborated_and_const_checked(
+    tcx: TyCtxt<'_>,
     def: ty::WithOptConstParam<LocalDefId>,
-) -> &'tcx Steal<Body<'tcx>> {
+) -> &Steal<Body<'_>> {
     if let Some(def) = def.try_upgrade(tcx) {
         return tcx.mir_drops_elaborated_and_const_checked(def);
     }
@@ -597,7 +591,7 @@ fn run_optimization_passes<'tcx>(tcx: TyCtxt<'tcx>, body: &mut Body<'tcx>) {
 }
 
 /// Optimize the MIR and prepare it for codegen.
-fn optimized_mir<'tcx>(tcx: TyCtxt<'tcx>, did: DefId) -> &'tcx Body<'tcx> {
+fn optimized_mir(tcx: TyCtxt<'_>, did: DefId) -> &Body<'_> {
     let did = did.expect_local();
     assert_eq!(ty::WithOptConstParam::try_lookup(did, tcx), None);
     tcx.arena.alloc(inner_optimized_mir(tcx, did))
@@ -634,10 +628,10 @@ fn inner_optimized_mir(tcx: TyCtxt<'_>, did: LocalDefId) -> Body<'_> {
 
 /// Fetch all the promoteds of an item and prepare their MIR bodies to be ready for
 /// constant evaluation once all substitutions become known.
-fn promoted_mir<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn promoted_mir(
+    tcx: TyCtxt<'_>,
     def: ty::WithOptConstParam<LocalDefId>,
-) -> &'tcx IndexVec<Promoted, Body<'tcx>> {
+) -> &IndexVec<Promoted, Body<'_>> {
     if tcx.is_constructor(def.did.to_def_id()) {
         return tcx.arena.alloc(IndexVec::new());
     }

compiler/rustc_mir_transform/src/simplify_try.rs

@@ -532,7 +532,7 @@ struct VarField<'tcx> {
 }
 
 /// Match on `((_LOCAL as Variant).FIELD: TY)`.
-fn match_variant_field_place<'tcx>(place: Place<'tcx>) -> Option<(Local, VarField<'tcx>)> {
+fn match_variant_field_place(place: Place<'_>) -> Option<(Local, VarField<'_>)> {
     match place.as_ref() {
         PlaceRef {
             local,

compiler/rustc_monomorphize/src/partitioning/mod.rs

@@ -345,10 +345,7 @@ where
     }
 }
 
-fn collect_and_partition_mono_items<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    (): (),
-) -> (&'tcx DefIdSet, &'tcx [CodegenUnit<'tcx>]) {
+fn collect_and_partition_mono_items(tcx: TyCtxt<'_>, (): ()) -> (&DefIdSet, &[CodegenUnit<'_>]) {
     let collection_mode = match tcx.sess.opts.unstable_opts.print_mono_items {
         Some(ref s) => {
             let mode_string = s.to_lowercase();
@@ -541,7 +538,7 @@ fn dump_mono_items_stats<'tcx>(
     Ok(())
 }
 
-fn codegened_and_inlined_items<'tcx>(tcx: TyCtxt<'tcx>, (): ()) -> &'tcx DefIdSet {
+fn codegened_and_inlined_items(tcx: TyCtxt<'_>, (): ()) -> &DefIdSet {
     let (items, cgus) = tcx.collect_and_partition_mono_items(());
     let mut visited = DefIdSet::default();
     let mut result = items.clone();

compiler/rustc_passes/src/dead.rs

@@ -571,7 +571,7 @@ fn check_item<'tcx>(
     }
 }
 
-fn check_trait_item<'tcx>(tcx: TyCtxt<'tcx>, worklist: &mut Vec<LocalDefId>, id: hir::TraitItemId) {
+fn check_trait_item(tcx: TyCtxt<'_>, worklist: &mut Vec<LocalDefId>, id: hir::TraitItemId) {
     use hir::TraitItemKind::{Const, Fn};
     if matches!(tcx.def_kind(id.owner_id), DefKind::AssocConst | DefKind::AssocFn) {
         let trait_item = tcx.hir().trait_item(id);
@@ -583,11 +583,7 @@ fn check_trait_item<'tcx>(tcx: TyCtxt<'tcx>, worklist: &mut Vec<LocalDefId>, id:
     }
 }
 
-fn check_foreign_item<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    worklist: &mut Vec<LocalDefId>,
-    id: hir::ForeignItemId,
-) {
+fn check_foreign_item(tcx: TyCtxt<'_>, worklist: &mut Vec<LocalDefId>, id: hir::ForeignItemId) {
     if matches!(tcx.def_kind(id.owner_id), DefKind::Static(_) | DefKind::Fn)
         && has_allow_dead_code_or_lang_attr(tcx, id.hir_id())
     {
@@ -595,8 +591,8 @@ fn check_foreign_item<'tcx>(
     }
 }
 
-fn create_and_seed_worklist<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn create_and_seed_worklist(
+    tcx: TyCtxt<'_>,
 ) -> (Vec<LocalDefId>, FxHashMap<LocalDefId, LocalDefId>) {
     let effective_visibilities = &tcx.effective_visibilities(());
     // see `MarkSymbolVisitor::struct_constructors`
@@ -626,8 +622,8 @@ fn create_and_seed_worklist<'tcx>(
     (worklist, struct_constructors)
 }
 
-fn live_symbols_and_ignored_derived_traits<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn live_symbols_and_ignored_derived_traits(
+    tcx: TyCtxt<'_>,
     (): (),
 ) -> (FxHashSet<LocalDefId>, FxHashMap<LocalDefId, Vec<(DefId, DefId)>>) {
     let (worklist, struct_constructors) = create_and_seed_worklist(tcx);

compiler/rustc_passes/src/debugger_visualizer.rs

@@ -15,8 +15,8 @@ use std::sync::Arc;
 
 use crate::errors::DebugVisualizerUnreadable;
 
-fn check_for_debugger_visualizer<'tcx>(
-    tcx: TyCtxt<'tcx>,
+fn check_for_debugger_visualizer(
+    tcx: TyCtxt<'_>,
     hir_id: HirId,
     debugger_visualizers: &mut FxHashSet<DebuggerVisualizerFile>,
 ) {
@@ -69,7 +69,7 @@ fn check_for_debugger_visualizer<'tcx>(
 }
 
 /// Traverses and collects the debugger visualizers for a specific crate.
-fn debugger_visualizers<'tcx>(tcx: TyCtxt<'tcx>, cnum: CrateNum) -> Vec<DebuggerVisualizerFile> {
+fn debugger_visualizers(tcx: TyCtxt<'_>, cnum: CrateNum) -> Vec<DebuggerVisualizerFile> {
     assert_eq!(cnum, LOCAL_CRATE);
 
     // Initialize the collector.

compiler/rustc_passes/src/diagnostic_items.rs

@@ -18,11 +18,7 @@ use rustc_span::symbol::{kw::Empty, sym, Symbol};
 
 use crate::errors::{DuplicateDiagnosticItem, DuplicateDiagnosticItemInCrate};
 
-fn observe_item<'tcx>(
-    tcx: TyCtxt<'tcx>,
-    diagnostic_items: &mut DiagnosticItems,
-    def_id: LocalDefId,
-) {
+fn observe_item(tcx: TyCtxt<'_>, diagnostic_items: &mut DiagnosticItems, def_id: LocalDefId) {
     let hir_id = tcx.hir().local_def_id_to_hir_id(def_id);
     let attrs = tcx.hir().attrs(hir_id);
     if let Some(name) = extract(attrs) {
@@ -63,7 +59,7 @@ fn extract(attrs: &[ast::Attribute]) -> Option<Symbol> {
 }
 
 /// Traverse and collect the diagnostic items in the current
-fn diagnostic_items<'tcx>(tcx: TyCtxt<'tcx>, cnum: CrateNum) -> DiagnosticItems {
+fn diagnostic_items(tcx: TyCtxt<'_>, cnum: CrateNum) -> DiagnosticItems {
     assert_eq!(cnum, LOCAL_CRATE);
 
     // Initialize the collector.
@@ -92,7 +88,7 @@ fn diagnostic_items<'tcx>(tcx: TyCtxt<'tcx>, cnum: CrateNum) -> DiagnosticItems
 }
 
 /// Traverse and collect all the diagnostic items in all crates.
-fn all_diagnostic_items<'tcx>(tcx: TyCtxt<'tcx>, (): ()) -> DiagnosticItems {
+fn all_diagnostic_items(tcx: TyCtxt<'_>, (): ()) -> DiagnosticItems {
     // Initialize the collector.
     let mut items = DiagnosticItems::default();
 

compiler/rustc_passes/src/layout_test.rs

@@ -26,7 +26,7 @@ pub fn test_layout(tcx: TyCtxt<'_>) {
     }
 }
 
-fn dump_layout_of<'tcx>(tcx: TyCtxt<'tcx>, item_def_id: LocalDefId, attr: &Attribute) {
+fn dump_layout_of(tcx: TyCtxt<'_>, item_def_id: LocalDefId, attr: &Attribute) {
     let tcx = tcx;
     let param_env = tcx.param_env(item_def_id);
     let ty = tcx.type_of(item_def_id);

compiler/rustc_passes/src/reachable.rs

@@ -347,7 +347,7 @@ fn check_item<'tcx>(
     }
 }
 
-fn has_custom_linkage<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> bool {
+fn has_custom_linkage(tcx: TyCtxt<'_>, def_id: LocalDefId) -> bool {
     // Anything which has custom linkage gets thrown on the worklist no
     // matter where it is in the crate, along with "special std symbols"
     // which are currently akin to allocator symbols.
@@ -364,7 +364,7 @@ fn has_custom_linkage<'tcx>(tcx: TyCtxt<'tcx>, def_id: LocalDefId) -> bool {
         || codegen_attrs.flags.contains(CodegenFnAttrFlags::USED_LINKER)
 }
 
-fn reachable_set<'tcx>(tcx: TyCtxt<'tcx>, (): ()) -> FxHashSet<LocalDefId> {
+fn reachable_set(tcx: TyCtxt<'_>, (): ()) -> FxHashSet<LocalDefId> {
     let effective_visibilities = &tcx.effective_visibilities(());
 
     let any_library =

compiler/rustc_passes/src/stability.rs

@@ -853,7 +853,7 @@ impl<'tcx> Visitor<'tcx> for Checker<'tcx> {
 /// Check whether a path is a `use` item that has been marked as unstable.
 ///
 /// See issue #94972 for details on why this is a special case
-fn is_unstable_reexport<'tcx>(tcx: TyCtxt<'tcx>, id: hir::HirId) -> bool {
+fn is_unstable_reexport(tcx: TyCtxt<'_>, id: hir::HirId) -> bool {
     // Get the LocalDefId so we can lookup the item to check the kind.
     let Some(def_id) = tcx.hir().opt_local_def_id(id) else { return false; };
 

compiler/rustc_passes/src/weak_lang_items.rs

@@ -11,7 +11,7 @@ use crate::errors::{MissingLangItem, MissingPanicHandler, UnknownExternLangItem}
 
 /// Checks the crate for usage of weak lang items, returning a vector of all the
 /// language items required by this crate, but not defined yet.
-pub fn check_crate<'tcx>(tcx: TyCtxt<'tcx>, items: &mut lang_items::LanguageItems) {
+pub fn check_crate(tcx: TyCtxt<'_>, items: &mut lang_items::LanguageItems) {
     // These are never called by user code, they're generated by the compiler.
     // They will never implicitly be added to the `missing` array unless we do
     // so here.
@@ -40,7 +40,7 @@ pub fn check_crate<'tcx>(tcx: TyCtxt<'tcx>, items: &mut lang_items::LanguageItem
     verify(tcx, items);
 }
 
-fn verify<'tcx>(tcx: TyCtxt<'tcx>, items: &lang_items::LanguageItems) {
+fn verify(tcx: TyCtxt<'_>, items: &lang_items::LanguageItems) {
     // We only need to check for the presence of weak lang items if we're
     // emitting something that's not an rlib.
     let needs_check = tcx.sess.crate_types().iter().any(|kind| match *kind {

compiler/rustc_query_impl/src/on_disk_cache.rs

@@ -227,7 +227,7 @@ impl<'sess> rustc_middle::ty::OnDiskCache<'sess> for OnDiskCache<'sess> {
         *self.serialized_data.write() = None;
     }
 
-    fn serialize<'tcx>(&self, tcx: TyCtxt<'tcx>, encoder: FileEncoder) -> FileEncodeResult {
+    fn serialize(&self, tcx: TyCtxt<'_>, encoder: FileEncoder) -> FileEncodeResult {
         // Serializing the `DepGraph` should not modify it.
         tcx.dep_graph.with_ignore(|| {
             // Allocate `SourceFileIndex`es.

compiler/rustc_query_impl/src/profiling_support.rs

@@ -278,7 +278,7 @@ pub(crate) fn alloc_self_profile_query_strings_for_query_cache<'tcx, C>(
 /// If we are recording only summary data, the ids will point to
 /// just the query names. If we are recording query keys too, we
 /// allocate the corresponding strings here.
-pub fn alloc_self_profile_query_strings<'tcx>(tcx: TyCtxt<'tcx>) {
+pub fn alloc_self_profile_query_strings(tcx: TyCtxt<'_>) {
     if !tcx.prof.enabled() {
         return;
     }

compiler/rustc_query_system/src/query/plumbing.rs

@@ -337,9 +337,9 @@ where
 /// which will be used if the query is not in the cache and we need
 /// to compute it.
 #[inline]
-pub fn try_get_cached<'a, Tcx, C, R, OnHit>(
+pub fn try_get_cached<Tcx, C, R, OnHit>(
     tcx: Tcx,
-    cache: &'a C,
+    cache: &C,
     key: &C::Key,
     // `on_hit` can be called while holding a lock to the query cache
     on_hit: OnHit,

compiler/rustc_save_analysis/src/lib.rs

@@ -957,10 +957,10 @@ impl SaveHandler for CallbackHandler<'_> {
     }
 }
 
-pub fn process_crate<'l, 'tcx, H: SaveHandler>(
-    tcx: TyCtxt<'tcx>,
+pub fn process_crate<H: SaveHandler>(
+    tcx: TyCtxt<'_>,
     cratename: Symbol,
-    input: &'l Input,
+    input: &Input,
     config: Option<Config>,
     mut handler: H,
 ) {

compiler/rustc_session/src/parse.rs

@@ -122,7 +122,7 @@ pub fn feature_err_issue<'a>(
 /// Construct a future incompatibility diagnostic for a feature gate.
 ///
 /// This diagnostic is only a warning and *does not cause compilation to fail*.
-pub fn feature_warn<'a>(sess: &'a ParseSess, feature: Symbol, span: Span, explain: &str) {
+pub fn feature_warn(sess: &ParseSess, feature: Symbol, span: Span, explain: &str) {
     feature_warn_issue(sess, feature, span, GateIssue::Language, explain);
 }
 
@@ -134,8 +134,8 @@ pub fn feature_warn<'a>(sess: &'a ParseSess, feature: Symbol, span: Span, explai
 /// Almost always, you want to use this for a language feature. If so, prefer `feature_warn`.
 #[allow(rustc::diagnostic_outside_of_impl)]
 #[allow(rustc::untranslatable_diagnostic)]
-pub fn feature_warn_issue<'a>(
-    sess: &'a ParseSess,
+pub fn feature_warn_issue(
+    sess: &ParseSess,
     feature: Symbol,
     span: Span,
     issue: GateIssue,
@@ -160,7 +160,7 @@ pub fn feature_warn_issue<'a>(
 }
 
 /// Adds the diagnostics for a feature to an existing error.
-pub fn add_feature_diagnostics<'a>(err: &mut Diagnostic, sess: &'a ParseSess, feature: Symbol) {
+pub fn add_feature_diagnostics(err: &mut Diagnostic, sess: &ParseSess, feature: Symbol) {
     add_feature_diagnostics_for_issue(err, sess, feature, GateIssue::Language);
 }
 
@@ -169,9 +169,9 @@ pub fn add_feature_diagnostics<'a>(err: &mut Diagnostic, sess: &'a ParseSess, fe
 /// This variant allows you to control whether it is a library or language feature.
 /// Almost always, you want to use this for a language feature. If so, prefer
 /// `add_feature_diagnostics`.
-pub fn add_feature_diagnostics_for_issue<'a>(
+pub fn add_feature_diagnostics_for_issue(
     err: &mut Diagnostic,
-    sess: &'a ParseSess,
+    sess: &ParseSess,
     feature: Symbol,
     issue: GateIssue,
 ) {

compiler/rustc_session/src/utils.rs

@@ -3,7 +3,7 @@ use rustc_data_structures::profiling::VerboseTimingGuard;
 use std::path::{Path, PathBuf};
 
 impl Session {
-    pub fn timer<'a>(&'a self, what: &'static str) -> VerboseTimingGuard<'a> {
+    pub fn timer(&self, what: &'static str) -> VerboseTimingGuard<'_> {
         self.prof.verbose_generic_activity(what)
     }
     pub fn time<R>(&self, what: &'static str, f: impl FnOnce() -> R) -> R {

compiler/rustc_symbol_mangling/src/typeid/typeid_itanium_cxx_abi.rs

@@ -338,7 +338,7 @@ fn encode_substs<'tcx>(
 }
 
 /// Encodes a ty:Ty name, including its crate and path disambiguators and names.
-fn encode_ty_name<'tcx>(tcx: TyCtxt<'tcx>, def_id: DefId) -> String {
+fn encode_ty_name(tcx: TyCtxt<'_>, def_id: DefId) -> String {
     // Encode <name> for use in u<length><name>[I<element-type1..element-typeN>E], where
     // <element-type> is <subst>, using v0's <path> without v0's extended form of paths:
     //

compiler/rustc_target/src/abi/call/loongarch.rs

@@ -19,7 +19,7 @@ enum FloatConv {
 #[derive(Copy, Clone)]
 struct CannotUseFpConv;
 
-fn is_loongarch_aggregate<'a, Ty>(arg: &ArgAbi<'a, Ty>) -> bool {
+fn is_loongarch_aggregate<Ty>(arg: &ArgAbi<'_, Ty>) -> bool {
     match arg.layout.abi {
         Abi::Vector { .. } => true,
         _ => arg.layout.is_aggregate(),
@@ -290,7 +290,7 @@ fn classify_arg<'a, Ty, C>(
     }
 }
 
-fn extend_integer_width<'a, Ty>(arg: &mut ArgAbi<'a, Ty>, xlen: u64) {
+fn extend_integer_width<Ty>(arg: &mut ArgAbi<'_, Ty>, xlen: u64) {
     if let Abi::Scalar(scalar) = arg.layout.abi {
         if let abi::Int(i, _) = scalar.primitive() {
             // 32-bit integers are always sign-extended

compiler/rustc_target/src/abi/call/riscv.rs

@@ -25,7 +25,7 @@ enum FloatConv {
 #[derive(Copy, Clone)]
 struct CannotUseFpConv;
 
-fn is_riscv_aggregate<'a, Ty>(arg: &ArgAbi<'a, Ty>) -> bool {
+fn is_riscv_aggregate<Ty>(arg: &ArgAbi<'_, Ty>) -> bool {
     match arg.layout.abi {
         Abi::Vector { .. } => true,
         _ => arg.layout.is_aggregate(),
@@ -296,7 +296,7 @@ fn classify_arg<'a, Ty, C>(
     }
 }
 
-fn extend_integer_width<'a, Ty>(arg: &mut ArgAbi<'a, Ty>, xlen: u64) {
+fn extend_integer_width<Ty>(arg: &mut ArgAbi<'_, Ty>, xlen: u64) {
     if let Abi::Scalar(scalar) = arg.layout.abi {
         if let abi::Int(i, _) = scalar.primitive() {
             // 32-bit integers are always sign-extended

compiler/rustc_target/src/spec/mod.rs

@@ -1319,7 +1319,7 @@ pub struct Target {
 }
 
 impl Target {
-    pub fn parse_data_layout<'a>(&'a self) -> Result<TargetDataLayout, TargetDataLayoutErrors<'a>> {
+    pub fn parse_data_layout(&self) -> Result<TargetDataLayout, TargetDataLayoutErrors<'_>> {
         let mut dl = TargetDataLayout::parse_from_llvm_datalayout_string(&self.data_layout)?;
 
         // Perform consistency checks against the Target information.

compiler/rustc_trait_selection/src/traits/coherence.rs

@@ -66,13 +66,13 @@ pub fn add_placeholder_note(err: &mut Diagnostic) {
 /// with a suitably-freshened `ImplHeader` with those types
 /// substituted. Otherwise, returns `None`.
 #[instrument(skip(tcx, skip_leak_check), level = "debug")]
-pub fn overlapping_impls<'tcx>(
-    tcx: TyCtxt<'tcx>,
+pub fn overlapping_impls(
+    tcx: TyCtxt<'_>,
     impl1_def_id: DefId,
     impl2_def_id: DefId,
     skip_leak_check: SkipLeakCheck,
     overlap_mode: OverlapMode,
-) -> Option<OverlapResult<'tcx>> {
+) -> Option<OverlapResult<'_>> {
     // Before doing expensive operations like entering an inference context, do
     // a quick check via fast_reject to tell if the impl headers could possibly
     // unify.
@@ -283,7 +283,7 @@ fn implicit_negative<'cx, 'tcx>(
 
 /// Given impl1 and impl2 check if both impls are never satisfied by a common type (including
 /// where-clauses) If so, return true, they are disjoint and false otherwise.
-fn negative_impl<'tcx>(tcx: TyCtxt<'tcx>, impl1_def_id: DefId, impl2_def_id: DefId) -> bool {
+fn negative_impl(tcx: TyCtxt<'_>, impl1_def_id: DefId, impl2_def_id: DefId) -> bool {
     debug!("negative_impl(impl1_def_id={:?}, impl2_def_id={:?})", impl1_def_id, impl2_def_id);
 
     // Create an infcx, taking the predicates of impl1 as assumptions:

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

@@ -3483,7 +3483,7 @@ fn hint_missing_borrow<'tcx>(
 
     let arg_spans = fn_decl.inputs.iter().map(|ty| ty.span);
 
-    fn get_deref_type_and_refs<'tcx>(mut ty: Ty<'tcx>) -> (Ty<'tcx>, usize) {
+    fn get_deref_type_and_refs(mut ty: Ty<'_>) -> (Ty<'_>, usize) {
         let mut refs = 0;
 
         while let ty::Ref(_, new_ty, _) = ty.kind() {