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

@@ -205,22 +205,19 @@ 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 };
 
         VerboseTimingGuard::start(message, self.generic_activity(event_label))
     }
 
     /// 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| {