1// ignore-tidy-filelength2//! "Late resolution" is the pass that resolves most of names in a crate beside imports and macros.3//! It runs when the crate is fully expanded and its module structure is fully built.4//! So it just walks through the crate and resolves all the expressions, types, etc.5//!6//! If you wonder why there's no `early.rs`, that's because it's split into three files -7//! `build_reduced_graph.rs`, `macros.rs` and `imports.rs`.89use std::borrow::Cow;10use std::collections::hash_map::Entry;11use std::debug_assert_matches;12use std::mem::{replace, swap, take};13use std::ops::{ControlFlow, Range};1415use rustc_ast::visit::{16 AssocCtxt, BoundKind, FnCtxt, FnKind, Visitor, try_visit, visit_opt, walk_list,17};18use rustc_ast::*;19use rustc_data_structures::either::Either;20use rustc_data_structures::fx::{FxHashMap, FxHashSet, FxIndexMap};21use rustc_data_structures::unord::{UnordMap, UnordSet};22use rustc_errors::codes::*;23use rustc_errors::{24 Applicability, Diag, DiagArgValue, Diagnostic, ErrorGuaranteed, IntoDiagArg, MultiSpan,25 StashKey, Suggestions, elided_lifetime_in_path_suggestion, pluralize,26};27use rustc_hir::def::Namespace::{self, *};28use rustc_hir::def::{CtorKind, DefKind, LifetimeRes, NonMacroAttrKind, PartialRes, PerNS};29use rustc_hir::def_id::{CRATE_DEF_ID, DefId, LOCAL_CRATE, LocalDefId};30use rustc_hir::{MissingLifetimeKind, PrimTy};31use rustc_middle::middle::resolve_bound_vars::Set1;32use rustc_middle::ty::{AssocTag, DelegationInfo, Visibility};33use rustc_middle::{bug, span_bug};34use rustc_session::config::{CrateType, ResolveDocLinks};35use rustc_session::errors::feature_err;36use rustc_session::lint;37use rustc_span::{BytePos, DUMMY_SP, Ident, Span, Spanned, Symbol, kw, respan, sym};38use smallvec::{SmallVec, smallvec};39use thin_vec::ThinVec;40use tracing::{debug, instrument, trace};4142use crate::{43 BindingError, BindingKey, Decl, DelegationFnSig, Finalize, IdentKey, LateDecl, LocalModule,44 Module, ModuleOrUniformRoot, ParentScope, PathResult, Res, ResolutionError, Resolver, Segment,45 Stage, TyCtxt, UseError, Used, path_names_to_string, rustdoc, with_owner,46};4748mod diagnostics;4950use diagnostics::{ElisionFnParameter, LifetimeElisionCandidate, MissingLifetime};5152#[derive(Copy, Clone, Debug)]53struct BindingInfo {54 span: Span,55 annotation: BindingMode,56}5758#[derive(Copy, Clone, PartialEq, Eq, Debug)]59pub(crate) enum PatternSource {60 Match,61 Let,62 For,63 FnParam,64}6566#[derive(Copy, Clone, Debug, PartialEq, Eq)]67enum IsRepeatExpr {68 No,69 Yes,70}7172struct IsNeverPattern;7374/// Describes whether an `AnonConst` is a type level const arg or75/// some other form of anon const (i.e. inline consts or enum discriminants)76#[derive(Copy, Clone, Debug, PartialEq, Eq)]77enum AnonConstKind {78 EnumDiscriminant,79 FieldDefaultValue,80 InlineConst,81 ConstArg(IsRepeatExpr),82}8384impl PatternSource {85 fn descr(self) -> &'static str {86 match self {87 PatternSource::Match => "match binding",88 PatternSource::Let => "let binding",89 PatternSource::For => "for binding",90 PatternSource::FnParam => "function parameter",91 }92 }93}9495impl IntoDiagArg for PatternSource {96 fn into_diag_arg(self, _: &mut Option<std::path::PathBuf>) -> DiagArgValue {97 DiagArgValue::Str(Cow::Borrowed(self.descr()))98 }99}100101/// Denotes whether the context for the set of already bound bindings is a `Product`102/// or `Or` context. This is used in e.g., `fresh_binding` and `resolve_pattern_inner`.103/// See those functions for more information.104#[derive(PartialEq)]105enum PatBoundCtx {106 /// A product pattern context, e.g., `Variant(a, b)`.107 Product,108 /// An or-pattern context, e.g., `p_0 | ... | p_n`.109 Or,110}111112/// Tracks bindings resolved within a pattern. This serves two purposes:113///114/// - This tracks when identifiers are bound multiple times within a pattern. In a product context,115/// this is an error. In an or-pattern, this lets us reuse the same resolution for each instance.116/// See `fresh_binding` and `resolve_pattern_inner` for more information.117///118/// - The guard expression of a guard pattern may use bindings from within the guard pattern, but119/// not from elsewhere in the pattern containing it. This allows us to isolate the bindings in the120/// subpattern to construct the scope for the guard.121///122/// Each identifier must map to at most one distinct [`Res`].123type PatternBindings = SmallVec<[(PatBoundCtx, FxIndexMap<Ident, Res>); 1]>;124125/// Does this the item (from the item rib scope) allow generic parameters?126#[derive(Copy, Clone, Debug)]127pub(crate) enum HasGenericParams {128 Yes(Span),129 No,130}131132/// May this constant have generics?133#[derive(Copy, Clone, Debug, Eq, PartialEq)]134pub(crate) enum ConstantHasGenerics {135 Yes,136 No(NoConstantGenericsReason),137}138139impl ConstantHasGenerics {140 fn force_yes_if(self, b: bool) -> Self {141 if b { Self::Yes } else { self }142 }143}144145/// Reason for why an anon const is not allowed to reference generic parameters146#[derive(Copy, Clone, Debug, Eq, PartialEq)]147pub(crate) enum NoConstantGenericsReason {148 /// Const arguments are only allowed to use generic parameters when:149 /// - `feature(generic_const_exprs)` is enabled150 /// or151 /// - the const argument is a sole const generic parameter, i.e. `foo::<{ N }>()`152 ///153 /// If neither of the above are true then this is used as the cause.154 NonTrivialConstArg,155 /// Enum discriminants are not allowed to reference generic parameters ever, this156 /// is used when an anon const is in the following position:157 ///158 /// ```rust,compile_fail159 /// enum Foo<const N: isize> {160 /// Variant = { N }, // this anon const is not allowed to use generics161 /// }162 /// ```163 IsEnumDiscriminant,164}165166#[derive(Copy, Clone, Debug, Eq, PartialEq)]167pub(crate) enum ConstantItemKind {168 Const,169 Static,170}171172impl ConstantItemKind {173 pub(crate) fn as_str(&self) -> &'static str {174 match self {175 Self::Const => "const",176 Self::Static => "static",177 }178 }179}180181#[derive(Debug, Copy, Clone, PartialEq, Eq)]182enum RecordPartialRes {183 Yes,184 No,185}186187/// The rib kind restricts certain accesses,188/// e.g. to a `Res::Local` of an outer item.189#[derive(Copy, Clone, Debug)]190pub(crate) enum RibKind<'ra> {191 /// No restriction needs to be applied.192 Normal,193194 /// We passed through an `ast::Block`.195 /// Behaves like `Normal`, but also partially like `Module` if the block contains items.196 /// `Block(None)` must be always processed in the same way as `Block(Some(module))`197 /// with empty `module`. The module can be `None` only because creation of some definitely198 /// empty modules is skipped as an optimization.199 Block(Option<LocalModule<'ra>>),200201 /// We passed through an impl or trait and are now in one of its202 /// methods or associated types. Allow references to ty params that impl or trait203 /// binds. Disallow any other upvars (including other ty params that are204 /// upvars).205 AssocItem,206207 /// We passed through a function, closure or coroutine signature. Disallow labels.208 FnOrCoroutine,209210 /// We passed through an item scope. Disallow upvars.211 Item(HasGenericParams, DefKind),212213 /// We're in a constant item. Can't refer to dynamic stuff.214 ///215 /// The item may reference generic parameters in trivial constant expressions.216 /// All other constants aren't allowed to use generic params at all.217 ConstantItem(ConstantHasGenerics, Option<(Ident, ConstantItemKind)>),218219 /// We passed through a module item.220 Module(LocalModule<'ra>),221222 /// We passed through a `macro_rules!` statement223 MacroDefinition(DefId),224225 /// All bindings in this rib are generic parameters that can't be used226 /// from the default of a generic parameter because they're not declared227 /// before said generic parameter. Also see the `visit_generics` override.228 ForwardGenericParamBan(ForwardGenericParamBanReason),229230 /// We are inside of the type of a const parameter. Can't refer to any231 /// parameters.232 ConstParamTy,233234 /// We are inside a `sym` inline assembly operand. Can only refer to235 /// globals.236 InlineAsmSym,237}238239#[derive(Copy, Clone, PartialEq, Eq, Debug)]240pub(crate) enum ForwardGenericParamBanReason {241 Default,242 ConstParamTy,243}244245impl RibKind<'_> {246 /// Whether this rib kind contains generic parameters, as opposed to local247 /// variables.248 pub(crate) fn contains_params(&self) -> bool {249 match self {250 RibKind::Normal251 | RibKind::Block(..)252 | RibKind::FnOrCoroutine253 | RibKind::ConstantItem(..)254 | RibKind::Module(_)255 | RibKind::MacroDefinition(_)256 | RibKind::InlineAsmSym => false,257 RibKind::ConstParamTy258 | RibKind::AssocItem259 | RibKind::Item(..)260 | RibKind::ForwardGenericParamBan(_) => true,261 }262 }263264 /// This rib forbids referring to labels defined in upwards ribs.265 fn is_label_barrier(self) -> bool {266 match self {267 RibKind::Normal | RibKind::MacroDefinition(..) => false,268 RibKind::FnOrCoroutine | RibKind::ConstantItem(..) => true,269 kind => bug!("unexpected rib kind: {kind:?}"),270 }271 }272}273274/// A single local scope.275///276/// A rib represents a scope names can live in. Note that these appear in many places, not just277/// around braces. At any place where the list of accessible names (of the given namespace)278/// changes or a new restrictions on the name accessibility are introduced, a new rib is put onto a279/// stack. This may be, for example, a `let` statement (because it introduces variables), a macro,280/// etc.281///282/// Different [rib kinds](enum@RibKind) are transparent for different names.283///284/// The resolution keeps a separate stack of ribs as it traverses the AST for each namespace. When285/// resolving, the name is looked up from inside out.286#[derive(Debug)]287pub(crate) struct Rib<'ra, R = Res> {288 pub bindings: FxIndexMap<Ident, R>,289 pub patterns_with_skipped_bindings: UnordMap<DefId, Vec<(Span, Result<(), ErrorGuaranteed>)>>,290 pub kind: RibKind<'ra>,291}292293impl<'ra, R> Rib<'ra, R> {294 fn new(kind: RibKind<'ra>) -> Rib<'ra, R> {295 Rib {296 bindings: Default::default(),297 patterns_with_skipped_bindings: Default::default(),298 kind,299 }300 }301}302303#[derive(Clone, Copy, Debug)]304enum LifetimeUseSet {305 One { use_span: Span, use_ctxt: visit::LifetimeCtxt },306 Many,307}308309#[derive(Copy, Clone, Debug)]310enum LifetimeRibKind {311 // -- Ribs introducing named lifetimes312 //313 /// This rib declares generic parameters.314 /// Only for this kind the `LifetimeRib::bindings` field can be non-empty.315 Generics { binder: NodeId, span: Span, kind: LifetimeBinderKind },316317 // -- Ribs introducing unnamed lifetimes318 //319 /// Create a new anonymous lifetime parameter and reference it.320 ///321 /// If `report_in_path`, report an error when encountering lifetime elision in a path:322 /// ```compile_fail323 /// struct Foo<'a> { x: &'a () }324 /// async fn foo(x: Foo) {}325 /// ```326 ///327 /// Note: the error should not trigger when the elided lifetime is in a pattern or328 /// expression-position path:329 /// ```330 /// struct Foo<'a> { x: &'a () }331 /// async fn foo(Foo { x: _ }: Foo<'_>) {}332 /// ```333 AnonymousCreateParameter { binder: NodeId, report_in_path: bool },334335 /// Replace all anonymous lifetimes by provided lifetime.336 Elided(LifetimeRes),337338 // -- Barrier ribs that stop lifetime lookup, or continue it but produce an error later.339 //340 /// Give a hard error when either `&` or `'_` is written. Used to341 /// rule out things like `where T: Foo<'_>`. Does not imply an342 /// error on default object bounds (e.g., `Box<dyn Foo>`).343 AnonymousReportError,344345 /// Resolves elided lifetimes to `'static` if there are no other lifetimes in scope,346 /// otherwise give a warning that the previous behavior of introducing a new early-bound347 /// lifetime is a bug and will be removed (if `emit_lint` is enabled).348 StaticIfNoLifetimeInScope { lint_id: NodeId, emit_lint: bool },349350 /// Signal we cannot find which should be the anonymous lifetime.351 ElisionFailure,352353 /// This rib forbids usage of generic parameters inside of const parameter types.354 ///355 /// While this is desirable to support eventually, it is difficult to do and so is356 /// currently forbidden. See rust-lang/project-const-generics#28 for more info.357 ConstParamTy,358359 /// Usage of generic parameters is forbidden in various positions for anon consts:360 /// - const arguments when `generic_const_exprs` is not enabled361 /// - enum discriminant values362 ///363 /// This rib emits an error when a lifetime would resolve to a lifetime parameter.364 ConcreteAnonConst(NoConstantGenericsReason),365366 /// This rib acts as a barrier to forbid reference to lifetimes of a parent item.367 Item,368369 /// Lifetimes cannot be elided in `impl Trait` types without `#![feature(anonymous_lifetime_in_impl_trait)]`.370 ImplTrait,371}372373#[derive(Copy, Clone, Debug)]374enum LifetimeBinderKind {375 FnPtrType,376 PolyTrait,377 WhereBound,378 // Item covers foreign items, ADTs, type aliases, trait associated items and379 // trait alias associated items.380 Item,381 ConstItem,382 Function,383 Closure,384 ImplBlock,385 // Covers only `impl` associated types.386 ImplAssocType,387}388389impl LifetimeBinderKind {390 fn descr(self) -> &'static str {391 use LifetimeBinderKind::*;392 match self {393 FnPtrType => "type",394 PolyTrait => "bound",395 WhereBound => "bound",396 Item | ConstItem => "item",397 ImplAssocType => "associated type",398 ImplBlock => "impl block",399 Function => "function",400 Closure => "closure",401 }402 }403}404405#[derive(Debug)]406struct LifetimeRib {407 kind: LifetimeRibKind,408 // We need to preserve insertion order for async fns.409 bindings: FxIndexMap<Ident, (NodeId, LifetimeRes)>,410}411412impl LifetimeRib {413 fn new(kind: LifetimeRibKind) -> LifetimeRib {414 LifetimeRib { bindings: Default::default(), kind }415 }416}417418#[derive(Copy, Clone, PartialEq, Eq, Debug)]419pub(crate) enum AliasPossibility {420 No,421 Maybe,422}423424#[derive(Copy, Clone, Debug)]425pub(crate) enum PathSource<'a, 'ast, 'ra> {426 /// Type paths `Path`.427 Type,428 /// Trait paths in bounds or impls.429 Trait(AliasPossibility),430 /// Expression paths `path`, with optional parent context.431 Expr(Option<&'ast Expr>),432 /// Paths in path patterns `Path`.433 Pat,434 /// Paths in struct expressions and patterns `Path { .. }`.435 Struct(Option<&'a Expr>),436 /// Paths in tuple struct patterns `Path(..)`.437 TupleStruct(Span, &'ra [Span]),438 /// `m::A::B` in `<T as m::A>::B::C`.439 ///440 /// Second field holds the "cause" of this one, i.e. the context within441 /// which the trait item is resolved. Used for diagnostics.442 TraitItem(Namespace, &'a PathSource<'a, 'ast, 'ra>),443 /// Paths in delegation item444 Delegation,445 /// Paths in externally implementable item declarations.446 ExternItemImpl,447 /// An arg in a `use<'a, N>` precise-capturing bound.448 PreciseCapturingArg(Namespace),449 /// Paths that end with `(..)`, for return type notation.450 ReturnTypeNotation,451 /// Paths from `#[define_opaque]` attributes452 DefineOpaques,453 /// Resolving a macro454 Macro,455 /// Paths for module or crate root. Used for restrictions.456 Module,457}458459impl PathSource<'_, '_, '_> {460 fn namespace(self) -> Namespace {461 match self {462 PathSource::Type463 | PathSource::Trait(_)464 | PathSource::Struct(_)465 | PathSource::DefineOpaques466 | PathSource::Module => TypeNS,467 PathSource::Expr(..)468 | PathSource::Pat469 | PathSource::TupleStruct(..)470 | PathSource::Delegation471 | PathSource::ExternItemImpl472 | PathSource::ReturnTypeNotation => ValueNS,473 PathSource::TraitItem(ns, _) => ns,474 PathSource::PreciseCapturingArg(ns) => ns,475 PathSource::Macro => MacroNS,476 }477 }478479 fn defer_to_typeck(self) -> bool {480 match self {481 PathSource::Type482 | PathSource::Expr(..)483 | PathSource::Pat484 | PathSource::Struct(_)485 | PathSource::TupleStruct(..)486 | PathSource::ReturnTypeNotation => true,487 PathSource::Trait(_)488 | PathSource::TraitItem(..)489 | PathSource::DefineOpaques490 | PathSource::Delegation491 | PathSource::ExternItemImpl492 | PathSource::PreciseCapturingArg(..)493 | PathSource::Macro494 | PathSource::Module => false,495 }496 }497498 fn descr_expected(self) -> &'static str {499 match &self {500 PathSource::DefineOpaques => "type alias or associated type with opaqaue types",501 PathSource::Type => "type",502 PathSource::Trait(_) => "trait",503 PathSource::Pat => "unit struct, unit variant or constant",504 PathSource::Struct(_) => "struct, variant or union type",505 PathSource::TraitItem(ValueNS, PathSource::TupleStruct(..))506 | PathSource::TupleStruct(..) => "tuple struct or tuple variant",507 PathSource::TraitItem(ns, _) => match ns {508 TypeNS => "associated type",509 ValueNS => "method or associated constant",510 MacroNS => bug!("associated macro"),511 },512 PathSource::Expr(parent) => match parent.as_ref().map(|p| &p.kind) {513 // "function" here means "anything callable" rather than `DefKind::Fn`,514 // this is not precise but usually more helpful than just "value".515 Some(ExprKind::Call(call_expr, _)) => match &call_expr.kind {516 // the case of `::some_crate()`517 ExprKind::Path(_, path)518 if let [segment, _] = path.segments.as_slice()519 && segment.ident.name == kw::PathRoot =>520 {521 "external crate"522 }523 ExprKind::Path(_, path)524 if let Some(segment) = path.segments.last()525 && let Some(c) = segment.ident.to_string().chars().next()526 && c.is_uppercase() =>527 {528 "function, tuple struct or tuple variant"529 }530 _ => "function",531 },532 _ => "value",533 },534 PathSource::ReturnTypeNotation | PathSource::Delegation => "function",535 PathSource::ExternItemImpl => "function or static",536 PathSource::PreciseCapturingArg(..) => "type or const parameter",537 PathSource::Macro => "macro",538 PathSource::Module => "module",539 }540 }541542 fn is_call(self) -> bool {543 matches!(self, PathSource::Expr(Some(&Expr { kind: ExprKind::Call(..), .. })))544 }545546 pub(crate) fn is_expected(self, res: Res) -> bool {547 match self {548 PathSource::DefineOpaques => {549 matches!(550 res,551 Res::Def(552 DefKind::Struct553 | DefKind::Union554 | DefKind::Enum555 | DefKind::TyAlias556 | DefKind::AssocTy,557 _558 ) | Res::SelfTyAlias { .. }559 )560 }561 PathSource::Type => matches!(562 res,563 Res::Def(564 DefKind::Struct565 | DefKind::Union566 | DefKind::Enum567 | DefKind::Trait568 | DefKind::TraitAlias569 | DefKind::TyAlias570 | DefKind::AssocTy571 | DefKind::TyParam572 | DefKind::OpaqueTy573 | DefKind::ForeignTy,574 _,575 ) | Res::PrimTy(..)576 | Res::SelfTyParam { .. }577 | Res::SelfTyAlias { .. }578 ),579 PathSource::Trait(AliasPossibility::No) => matches!(res, Res::Def(DefKind::Trait, _)),580 PathSource::Trait(AliasPossibility::Maybe) => {581 matches!(res, Res::Def(DefKind::Trait | DefKind::TraitAlias, _))582 }583 PathSource::Expr(..) => matches!(584 res,585 Res::Def(586 DefKind::Ctor(_, CtorKind::Const | CtorKind::Fn)587 | DefKind::Const { .. }588 | DefKind::Static { .. }589 | DefKind::Fn590 | DefKind::AssocFn591 | DefKind::AssocConst { .. }592 | DefKind::ConstParam,593 _,594 ) | Res::Local(..)595 | Res::SelfCtor(..)596 ),597 PathSource::Pat => {598 res.expected_in_unit_struct_pat()599 || matches!(600 res,601 Res::Def(DefKind::Const { .. } | DefKind::AssocConst { .. }, _)602 )603 }604 PathSource::TupleStruct(..) => res.expected_in_tuple_struct_pat(),605 PathSource::Struct(_) => matches!(606 res,607 Res::Def(608 DefKind::Struct609 | DefKind::Union610 | DefKind::Variant611 | DefKind::TyAlias612 | DefKind::AssocTy,613 _,614 ) | Res::SelfTyParam { .. }615 | Res::SelfTyAlias { .. }616 ),617 PathSource::TraitItem(ns, _) => match res {618 Res::Def(DefKind::AssocConst { .. } | DefKind::AssocFn, _) if ns == ValueNS => true,619 Res::Def(DefKind::AssocTy, _) if ns == TypeNS => true,620 _ => false,621 },622 PathSource::ReturnTypeNotation => match res {623 Res::Def(DefKind::AssocFn, _) => true,624 _ => false,625 },626 PathSource::Delegation => matches!(res, Res::Def(DefKind::Fn | DefKind::AssocFn, _)),627 PathSource::ExternItemImpl => {628 matches!(629 res,630 Res::Def(631 DefKind::Fn | DefKind::AssocFn | DefKind::Ctor(..) | DefKind::Static { .. },632 _633 )634 )635 }636 PathSource::PreciseCapturingArg(ValueNS) => {637 matches!(res, Res::Def(DefKind::ConstParam, _))638 }639 // We allow `SelfTyAlias` here so we can give a more descriptive error later.640 PathSource::PreciseCapturingArg(TypeNS) => matches!(641 res,642 Res::Def(DefKind::TyParam, _) | Res::SelfTyParam { .. } | Res::SelfTyAlias { .. }643 ),644 PathSource::PreciseCapturingArg(MacroNS) => false,645 PathSource::Macro => matches!(res, Res::Def(DefKind::Macro(_), _)),646 PathSource::Module => matches!(res, Res::Def(DefKind::Mod, _)),647 }648 }649650 fn error_code(self, has_unexpected_resolution: bool) -> ErrCode {651 match (self, has_unexpected_resolution) {652 (PathSource::Trait(_), true) => E0404,653 (PathSource::Trait(_), false) => E0405,654 (PathSource::Type | PathSource::DefineOpaques, true) => E0573,655 (PathSource::Type | PathSource::DefineOpaques, false) => E0425,656 (PathSource::Struct(_), true) => E0574,657 (PathSource::Struct(_), false) => E0422,658 (PathSource::Expr(..), true)659 | (PathSource::Delegation, true)660 | (PathSource::ExternItemImpl, true) => E0423,661 (PathSource::Expr(..), false)662 | (PathSource::Delegation, false)663 | (PathSource::ExternItemImpl, false) => E0425,664 (PathSource::Pat | PathSource::TupleStruct(..), true) => E0532,665 (PathSource::Pat | PathSource::TupleStruct(..), false) => E0531,666 (PathSource::TraitItem(..) | PathSource::ReturnTypeNotation, true) => E0575,667 (PathSource::TraitItem(..) | PathSource::ReturnTypeNotation, false) => E0576,668 (PathSource::PreciseCapturingArg(..), true) => E0799,669 (PathSource::PreciseCapturingArg(..), false) => E0800,670 (PathSource::Macro, _) => E0425,671 // FIXME: There is no dedicated error code for this case yet.672 // E0577 already covers the same situation for visibilities,673 // so we reuse it here for now. It may make sense to generalize674 // it for restrictions in the future.675 (PathSource::Module, true) => E0577,676 (PathSource::Module, false) => E0433,677 }678 }679}680681/// At this point for most items we can answer whether that item is exported or not,682/// but some items like impls require type information to determine exported-ness, so we make a683/// conservative estimate for them (e.g. based on nominal visibility).684#[derive(Clone, Copy)]685enum MaybeExported<'a> {686 Ok(NodeId),687 Impl(Option<DefId>),688 ImplItem(Result<DefId, &'a ast::Visibility>),689 NestedUse(&'a ast::Visibility),690}691692impl MaybeExported<'_> {693 fn eval(self, r: &Resolver<'_, '_>) -> bool {694 let def_id = match self {695 MaybeExported::Ok(node_id) => Some(if r.current_owner.id == node_id {696 r.current_owner.def_id697 } else {698 r.current_owner.node_id_to_def_id[&node_id]699 }),700 MaybeExported::Impl(Some(trait_def_id)) | MaybeExported::ImplItem(Ok(trait_def_id)) => {701 trait_def_id.as_local()702 }703 MaybeExported::Impl(None) => return true,704 MaybeExported::ImplItem(Err(vis)) | MaybeExported::NestedUse(vis) => {705 return vis.kind.is_pub();706 }707 };708 def_id.is_none_or(|def_id| r.effective_visibilities.is_exported(def_id))709 }710}711712/// Used for recording UnnecessaryQualification.713#[derive(Debug)]714pub(crate) struct UnnecessaryQualification<'ra> {715 pub decl: LateDecl<'ra>,716 pub node_id: NodeId,717 pub path_span: Span,718 pub removal_span: Span,719}720721#[derive(Default, Debug)]722pub(crate) struct DiagMetadata<'ast> {723 /// The current trait's associated items' ident, used for diagnostic suggestions.724 current_trait_assoc_items: Option<&'ast [Box<AssocItem>]>,725726 /// The current self type if inside an impl (used for better errors).727 pub(crate) current_self_type: Option<&'ast Ty>,728729 /// The current self item if inside an ADT (used for better errors).730 current_self_item: Option<NodeId>,731732 /// The current item being evaluated (used for suggestions and more detail in errors).733 pub(crate) current_item: Option<&'ast Item>,734735 /// When processing generic arguments and encountering an unresolved ident not found,736 /// suggest introducing a type or const param depending on the context.737 currently_processing_generic_args: bool,738739 /// The current enclosing (non-closure) function (used for better errors).740 current_function: Option<(FnKind<'ast>, Span)>,741742 /// A list of labels as of yet unused. Labels will be removed from this map when743 /// they are used (in a `break` or `continue` statement)744 unused_labels: FxIndexMap<NodeId, Span>,745746 /// Only used for better errors on `let <pat>: <expr, not type>;`.747 current_let_binding: Option<(Span, Option<Span>, Option<Span>)>,748749 current_pat: Option<&'ast Pat>,750751 /// Used to detect possible `if let` written without `let` and to provide structured suggestion.752 in_if_condition: Option<&'ast Expr>,753754 /// Used to detect possible new binding written without `let` and to provide structured suggestion.755 in_assignment: Option<&'ast Expr>,756 is_assign_rhs: bool,757758 /// If we are setting an associated type in trait impl, is it a non-GAT type?759 in_non_gat_assoc_type: Option<bool>,760761 /// Used to detect possible `.` -> `..` typo when calling methods.762 in_range: Option<(&'ast Expr, &'ast Expr)>,763764 /// If we are currently in a trait object definition. Used to point at the bounds when765 /// encountering a struct or enum.766 current_trait_object: Option<&'ast [ast::GenericBound]>,767768 /// Given `where <T as Bar>::Baz: String`, suggest `where T: Bar<Baz = String>`.769 current_where_predicate: Option<&'ast WherePredicate>,770771 /// Whether we are visiting an associated type equality binding like `Trait<Assoc = &T>`.772 in_assoc_ty_binding: bool,773774 current_type_path: Option<&'ast Ty>,775776 /// The current impl items (used to suggest).777 current_impl_items: Option<&'ast [Box<AssocItem>]>,778779 /// The current impl items (used to suggest).780 current_impl_item: Option<&'ast AssocItem>,781782 /// When processing impl trait783 currently_processing_impl_trait: Option<(TraitRef, Ty)>,784785 /// Accumulate the errors due to missed lifetime elision,786 /// and report them all at once for each function.787 current_elision_failures: Vec<(MissingLifetime, Either<NodeId, Range<NodeId>>)>,788}789790struct LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {791 r: &'a mut Resolver<'ra, 'tcx>,792793 /// The module that represents the current item scope.794 parent_scope: ParentScope<'ra>,795796 /// The current set of local scopes for types and values.797 ribs: PerNS<Vec<Rib<'ra>>>,798799 /// Previous popped `rib`, only used for diagnostic.800 last_block_rib: Option<Rib<'ra>>,801802 /// The current set of local scopes, for labels.803 label_ribs: Vec<Rib<'ra, NodeId>>,804805 /// The current set of local scopes for lifetimes.806 lifetime_ribs: Vec<LifetimeRib>,807808 /// We are looking for lifetimes in an elision context.809 /// The set contains all the resolutions that we encountered so far.810 /// They will be used to determine the correct lifetime for the fn return type.811 /// The `LifetimeElisionCandidate` is used for diagnostics, to suggest introducing named812 /// lifetimes.813 lifetime_elision_candidates: Option<Vec<(LifetimeRes, LifetimeElisionCandidate)>>,814815 /// The trait that the current context can refer to.816 current_trait_ref: Option<(Module<'ra>, TraitRef)>,817818 /// Fields used to add information to diagnostic errors.819 diag_metadata: Box<DiagMetadata<'ast>>,820821 /// State used to know whether to ignore resolution errors for function bodies.822 ///823 /// In particular, rustdoc uses this to avoid giving errors for `cfg()` items.824 /// In most cases this will be `None`, in which case errors will always be reported.825 /// If it is `true`, then it will be updated when entering a nested function or trait body.826 in_func_body: bool,827828 /// Count the number of places a lifetime is used.829 lifetime_uses: FxHashMap<LocalDefId, LifetimeUseSet>,830}831832impl<'ra, 'tcx> AsRef<Resolver<'ra, 'tcx>> for LateResolutionVisitor<'_, '_, 'ra, 'tcx> {833 fn as_ref(&self) -> &Resolver<'ra, 'tcx> {834 &self.r835 }836}837impl<'ra, 'tcx> AsMut<Resolver<'ra, 'tcx>> for LateResolutionVisitor<'_, '_, 'ra, 'tcx> {838 fn as_mut(&mut self) -> &mut Resolver<'ra, 'tcx> {839 &mut self.r840 }841}842843/// Walks the whole crate in DFS order, visiting each item, resolving names as it goes.844impl<'ast, 'ra, 'tcx> Visitor<'ast> for LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> {845 fn visit_attribute(&mut self, _: &'ast Attribute) {846 // We do not want to resolve expressions that appear in attributes,847 // as they do not correspond to actual code.848 }849 fn visit_item(&mut self, item: &'ast Item) {850 let prev = replace(&mut self.diag_metadata.current_item, Some(item));851 // Always report errors in items we just entered.852 let old_ignore = replace(&mut self.in_func_body, false);853 with_owner(self, item.id, |this| {854 this.with_lifetime_rib(LifetimeRibKind::Item, |this| this.resolve_item(item))855 });856 self.in_func_body = old_ignore;857 self.diag_metadata.current_item = prev;858 }859 fn visit_arm(&mut self, arm: &'ast Arm) {860 self.resolve_arm(arm);861 }862 fn visit_block(&mut self, block: &'ast Block) {863 let old_macro_rules = self.parent_scope.macro_rules;864 self.resolve_block(block);865 self.parent_scope.macro_rules = old_macro_rules;866 }867 fn visit_anon_const(&mut self, constant: &'ast AnonConst) {868 bug!("encountered anon const without a manual call to `resolve_anon_const`: {constant:#?}");869 }870 fn visit_expr(&mut self, expr: &'ast Expr) {871 self.resolve_expr(expr, None);872 }873 fn visit_pat(&mut self, p: &'ast Pat) {874 let prev = self.diag_metadata.current_pat;875 self.diag_metadata.current_pat = Some(p);876877 if let PatKind::Guard(subpat, _) = &p.kind {878 // We walk the guard expression in `resolve_pattern_inner`. Don't resolve it twice.879 self.visit_pat(subpat);880 } else {881 visit::walk_pat(self, p);882 }883884 self.diag_metadata.current_pat = prev;885 }886 fn visit_local(&mut self, local: &'ast Local) {887 let local_spans = match local.pat.kind {888 // We check for this to avoid tuple struct fields.889 PatKind::Wild => None,890 _ => Some((891 local.pat.span,892 local.ty.as_ref().map(|ty| ty.span),893 local.kind.init().map(|init| init.span),894 )),895 };896 let original = replace(&mut self.diag_metadata.current_let_binding, local_spans);897 self.resolve_local(local);898 self.diag_metadata.current_let_binding = original;899 }900 fn visit_ty(&mut self, ty: &'ast Ty) {901 let prev = self.diag_metadata.current_trait_object;902 let prev_ty = self.diag_metadata.current_type_path;903 match &ty.kind {904 TyKind::Ref(None, _) | TyKind::PinnedRef(None, _) => {905 // Elided lifetime in reference: we resolve as if there was some lifetime `'_` with906 // NodeId `ty.id`.907 // This span will be used in case of elision failure.908 let span = self.r.tcx.sess.source_map().start_point(ty.span);909 self.resolve_elided_lifetime(ty.id, span);910 visit::walk_ty(self, ty);911 }912 TyKind::Path(qself, path) => {913 self.diag_metadata.current_type_path = Some(ty);914915 // If we have a path that ends with `(..)`, then it must be916 // return type notation. Resolve that path in the *value*917 // namespace.918 let source = if let Some(seg) = path.segments.last()919 && let Some(args) = &seg.args920 && matches!(**args, GenericArgs::ParenthesizedElided(..))921 {922 PathSource::ReturnTypeNotation923 } else {924 PathSource::Type925 };926927 self.smart_resolve_path(ty.id, qself, path, source);928929 // Check whether we should interpret this as a bare trait object.930 if qself.is_none()931 && let Some(partial_res) = self.r.partial_res_map.get(&ty.id)932 && let Some(Res::Def(DefKind::Trait | DefKind::TraitAlias, _)) =933 partial_res.full_res()934 {935 // This path is actually a bare trait object. In case of a bare `Fn`-trait936 // object with anonymous lifetimes, we need this rib to correctly place the937 // synthetic lifetimes.938 let span = ty.span.shrink_to_lo().to(path.span.shrink_to_lo());939 self.with_generic_param_rib(940 &[],941 RibKind::Normal,942 ty.id,943 LifetimeBinderKind::PolyTrait,944 span,945 |this| this.visit_path(path),946 );947 } else {948 visit::walk_ty(self, ty)949 }950 }951 TyKind::ImplicitSelf => {952 let self_ty = Ident::with_dummy_span(kw::SelfUpper);953 let res = self954 .resolve_ident_in_lexical_scope(955 self_ty,956 TypeNS,957 Some(Finalize::new(ty.id, ty.span)),958 None,959 )960 .map_or(Res::Err, |d| d.res());961 self.r.record_partial_res(ty.id, PartialRes::new(res));962 visit::walk_ty(self, ty)963 }964 TyKind::ImplTrait(..) => {965 let candidates = self.lifetime_elision_candidates.take();966 self.with_lifetime_rib(LifetimeRibKind::ImplTrait, |this| visit::walk_ty(this, ty));967 self.lifetime_elision_candidates = candidates;968 }969 TyKind::TraitObject(bounds, ..) => {970 self.diag_metadata.current_trait_object = Some(&bounds[..]);971 visit::walk_ty(self, ty)972 }973 TyKind::FnPtr(fn_ptr) => {974 let span = ty.span.shrink_to_lo().to(fn_ptr.decl_span.shrink_to_lo());975 self.with_generic_param_rib(976 &fn_ptr.generic_params,977 RibKind::Normal,978 ty.id,979 LifetimeBinderKind::FnPtrType,980 span,981 |this| {982 this.visit_generic_params(&fn_ptr.generic_params, false);983 this.resolve_fn_signature(984 ty.id,985 false,986 // We don't need to deal with patterns in parameters, because987 // they are not possible for foreign or bodiless functions.988 fn_ptr.decl.inputs.iter().map(|Param { ty, .. }| (None, &**ty)),989 &fn_ptr.decl.output,990 false,991 )992 },993 )994 }995 TyKind::UnsafeBinder(unsafe_binder) => {996 let span = ty.span.shrink_to_lo().to(unsafe_binder.inner_ty.span.shrink_to_lo());997 self.with_generic_param_rib(998 &unsafe_binder.generic_params,999 RibKind::Normal,1000 ty.id,1001 LifetimeBinderKind::FnPtrType,1002 span,1003 |this| {1004 this.visit_generic_params(&unsafe_binder.generic_params, false);1005 this.with_lifetime_rib(1006 // We don't allow anonymous `unsafe &'_ ()` binders,1007 // although I guess we could.1008 LifetimeRibKind::AnonymousReportError,1009 |this| this.visit_ty(&unsafe_binder.inner_ty),1010 );1011 },1012 )1013 }1014 TyKind::Array(element_ty, length) => {1015 self.visit_ty(element_ty);1016 self.resolve_anon_const(length, AnonConstKind::ConstArg(IsRepeatExpr::No));1017 }1018 _ => visit::walk_ty(self, ty),1019 }1020 self.diag_metadata.current_trait_object = prev;1021 self.diag_metadata.current_type_path = prev_ty;1022 }10231024 fn visit_ty_pat(&mut self, t: &'ast TyPat) -> Self::Result {1025 match &t.kind {1026 TyPatKind::Range(start, end, _) => {1027 if let Some(start) = start {1028 self.resolve_anon_const(start, AnonConstKind::ConstArg(IsRepeatExpr::No));1029 }1030 if let Some(end) = end {1031 self.resolve_anon_const(end, AnonConstKind::ConstArg(IsRepeatExpr::No));1032 }1033 }1034 TyPatKind::Or(patterns) => {1035 for pat in patterns {1036 self.visit_ty_pat(pat)1037 }1038 }1039 TyPatKind::NotNull | TyPatKind::Err(_) => {}1040 }1041 }10421043 fn visit_poly_trait_ref(&mut self, tref: &'ast PolyTraitRef) {1044 let span = tref.span.shrink_to_lo().to(tref.trait_ref.path.span.shrink_to_lo());1045 self.with_generic_param_rib(1046 &tref.bound_generic_params,1047 RibKind::Normal,1048 tref.trait_ref.ref_id,1049 LifetimeBinderKind::PolyTrait,1050 span,1051 |this| {1052 this.visit_generic_params(&tref.bound_generic_params, false);1053 this.smart_resolve_path(1054 tref.trait_ref.ref_id,1055 &None,1056 &tref.trait_ref.path,1057 PathSource::Trait(AliasPossibility::Maybe),1058 );1059 this.visit_trait_ref(&tref.trait_ref);1060 },1061 );1062 }1063 fn visit_foreign_item(&mut self, foreign_item: &'ast ForeignItem) {1064 with_owner(self, foreign_item.id, |this| {1065 this.resolve_doc_links(&foreign_item.attrs, MaybeExported::Ok(foreign_item.id));1066 let def_kind = this.r.tcx.def_kind(this.r.current_owner.def_id);1067 match foreign_item.kind {1068 ForeignItemKind::TyAlias(TyAlias { ref generics, .. }) => {1069 this.with_generic_param_rib(1070 &generics.params,1071 RibKind::Item(HasGenericParams::Yes(generics.span), def_kind),1072 foreign_item.id,1073 LifetimeBinderKind::Item,1074 generics.span,1075 |this| visit::walk_item(this, foreign_item),1076 );1077 }1078 ForeignItemKind::Fn(Fn { ref generics, .. }) => {1079 this.with_generic_param_rib(1080 &generics.params,1081 RibKind::Item(HasGenericParams::Yes(generics.span), def_kind),1082 foreign_item.id,1083 LifetimeBinderKind::Function,1084 generics.span,1085 |this| visit::walk_item(this, foreign_item),1086 );1087 }1088 ForeignItemKind::Static(..) => {1089 this.with_static_rib(def_kind, |this| visit::walk_item(this, foreign_item))1090 }1091 ForeignItemKind::MacCall(..) => {1092 panic!("unexpanded macro in resolve!")1093 }1094 }1095 })1096 }1097 fn visit_fn(&mut self, fn_kind: FnKind<'ast>, _: &AttrVec, sp: Span, fn_id: NodeId) {1098 let previous_value = self.diag_metadata.current_function;1099 match fn_kind {1100 // Bail if the function is foreign, and thus cannot validly have1101 // a body, or if there's no body for some other reason.1102 FnKind::Fn(FnCtxt::Foreign, _, Fn { sig, ident, generics, .. })1103 | FnKind::Fn(_, _, Fn { sig, ident, generics, body: None, .. }) => {1104 self.visit_fn_header(&sig.header);1105 self.visit_ident(ident);1106 self.visit_generics(generics);1107 self.resolve_fn_signature(1108 fn_id,1109 sig.decl.has_self(),1110 sig.decl.inputs.iter().map(|Param { ty, .. }| (None, &**ty)),1111 &sig.decl.output,1112 false,1113 );1114 return;1115 }1116 FnKind::Fn(..) => {1117 self.diag_metadata.current_function = Some((fn_kind, sp));1118 }1119 // Do not update `current_function` for closures: it suggests `self` parameters.1120 FnKind::Closure(..) => {}1121 };1122 debug!("(resolving function) entering function");11231124 if let FnKind::Fn(_, _, f) = fn_kind {1125 self.resolve_eii(&f.eii_impls);1126 }11271128 // Create a value rib for the function.1129 self.with_rib(ValueNS, RibKind::FnOrCoroutine, |this| {1130 // Create a label rib for the function.1131 this.with_label_rib(RibKind::FnOrCoroutine, |this| {1132 match fn_kind {1133 FnKind::Fn(_, _, Fn { sig, generics, contract, body, .. }) => {1134 this.visit_generics(generics);11351136 let declaration = &sig.decl;1137 let coro_node_id = sig1138 .header1139 .coroutine_kind1140 .map(|coroutine_kind| coroutine_kind.return_id());11411142 this.resolve_fn_signature(1143 fn_id,1144 declaration.has_self(),1145 declaration1146 .inputs1147 .iter()1148 .map(|Param { pat, ty, .. }| (Some(&**pat), &**ty)),1149 &declaration.output,1150 coro_node_id.is_some(),1151 );11521153 if let Some(contract) = contract {1154 this.visit_contract(contract);1155 }11561157 if let Some(body) = body {1158 // Ignore errors in function bodies if this is rustdoc1159 // Be sure not to set this until the function signature has been resolved.1160 let previous_state = replace(&mut this.in_func_body, true);1161 // We only care block in the same function1162 this.last_block_rib = None;1163 // Resolve the function body, potentially inside the body of an async closure1164 this.with_lifetime_rib(1165 LifetimeRibKind::Elided(LifetimeRes::Infer),1166 |this| this.visit_block(body),1167 );11681169 debug!("(resolving function) leaving function");1170 this.in_func_body = previous_state;1171 }1172 }1173 FnKind::Closure(binder, _, declaration, body) => {1174 this.visit_closure_binder(binder);11751176 this.with_lifetime_rib(1177 match binder {1178 // We do not have any explicit generic lifetime parameter.1179 ClosureBinder::NotPresent => {1180 LifetimeRibKind::AnonymousCreateParameter {1181 binder: fn_id,1182 report_in_path: false,1183 }1184 }1185 ClosureBinder::For { .. } => LifetimeRibKind::AnonymousReportError,1186 },1187 // Add each argument to the rib.1188 |this| this.resolve_params(&declaration.inputs),1189 );1190 this.with_lifetime_rib(1191 match binder {1192 ClosureBinder::NotPresent => {1193 LifetimeRibKind::Elided(LifetimeRes::Infer)1194 }1195 ClosureBinder::For { .. } => LifetimeRibKind::AnonymousReportError,1196 },1197 |this| visit::walk_fn_ret_ty(this, &declaration.output),1198 );11991200 // Ignore errors in function bodies if this is rustdoc1201 // Be sure not to set this until the function signature has been resolved.1202 let previous_state = replace(&mut this.in_func_body, true);1203 // Resolve the function body, potentially inside the body of an async closure1204 this.with_lifetime_rib(1205 LifetimeRibKind::Elided(LifetimeRes::Infer),1206 |this| this.visit_expr(body),1207 );12081209 debug!("(resolving function) leaving function");1210 this.in_func_body = previous_state;1211 }1212 }1213 })1214 });1215 self.diag_metadata.current_function = previous_value;1216 }12171218 fn visit_lifetime(&mut self, lifetime: &'ast Lifetime, use_ctxt: visit::LifetimeCtxt) {1219 self.resolve_lifetime(lifetime, use_ctxt)1220 }12211222 fn visit_precise_capturing_arg(&mut self, arg: &'ast PreciseCapturingArg) {1223 match arg {1224 // Lower the lifetime regularly; we'll resolve the lifetime and check1225 // it's a parameter later on in HIR lowering.1226 PreciseCapturingArg::Lifetime(_) => {}12271228 PreciseCapturingArg::Arg(path, id) => {1229 // we want `impl use<C>` to try to resolve `C` as both a type parameter or1230 // a const parameter. Since the resolver specifically doesn't allow having1231 // two generic params with the same name, even if they're a different namespace,1232 // it doesn't really matter which we try resolving first, but just like1233 // `Ty::Param` we just fall back to the value namespace only if it's missing1234 // from the type namespace.1235 let mut check_ns = |ns| {1236 self.maybe_resolve_ident_in_lexical_scope(path.segments[0].ident, ns).is_some()1237 };1238 // Like `Ty::Param`, we try resolving this as both a const and a type.1239 if !check_ns(TypeNS) && check_ns(ValueNS) {1240 self.smart_resolve_path(1241 *id,1242 &None,1243 path,1244 PathSource::PreciseCapturingArg(ValueNS),1245 );1246 } else {1247 self.smart_resolve_path(1248 *id,1249 &None,1250 path,1251 PathSource::PreciseCapturingArg(TypeNS),1252 );1253 }1254 }1255 }12561257 visit::walk_precise_capturing_arg(self, arg)1258 }12591260 fn visit_generics(&mut self, generics: &'ast Generics) {1261 self.visit_generic_params(&generics.params, self.diag_metadata.current_self_item.is_some());1262 for p in &generics.where_clause.predicates {1263 self.visit_where_predicate(p);1264 }1265 }12661267 fn visit_closure_binder(&mut self, b: &'ast ClosureBinder) {1268 match b {1269 ClosureBinder::NotPresent => {}1270 ClosureBinder::For { generic_params, .. } => {1271 self.visit_generic_params(1272 generic_params,1273 self.diag_metadata.current_self_item.is_some(),1274 );1275 }1276 }1277 }12781279 fn visit_generic_arg(&mut self, arg: &'ast GenericArg) {1280 debug!("visit_generic_arg({:?})", arg);1281 let prev = replace(&mut self.diag_metadata.currently_processing_generic_args, true);1282 match arg {1283 GenericArg::Type(ty) => {1284 // We parse const arguments as path types as we cannot distinguish them during1285 // parsing. We try to resolve that ambiguity by attempting resolution the type1286 // namespace first, and if that fails we try again in the value namespace. If1287 // resolution in the value namespace succeeds, we have an generic const argument on1288 // our hands.1289 if let TyKind::Path(None, ref path) = ty.kind1290 // We cannot disambiguate multi-segment paths right now as that requires type1291 // checking.1292 && path.is_potential_trivial_const_arg()1293 {1294 let mut check_ns = |ns| {1295 self.maybe_resolve_ident_in_lexical_scope(path.segments[0].ident, ns)1296 .is_some()1297 };1298 if !check_ns(TypeNS) && check_ns(ValueNS) {1299 self.resolve_anon_const_manual(1300 true,1301 AnonConstKind::ConstArg(IsRepeatExpr::No),1302 |this| {1303 this.smart_resolve_path(ty.id, &None, path, PathSource::Expr(None));1304 this.visit_path(path);1305 },1306 );13071308 self.diag_metadata.currently_processing_generic_args = prev;1309 return;1310 }1311 }13121313 self.visit_ty(ty);1314 }1315 GenericArg::Lifetime(lt) => self.visit_lifetime(lt, visit::LifetimeCtxt::GenericArg),1316 GenericArg::Const(ct) => {1317 self.resolve_anon_const(ct, AnonConstKind::ConstArg(IsRepeatExpr::No))1318 }1319 }1320 self.diag_metadata.currently_processing_generic_args = prev;1321 }13221323 fn visit_assoc_item_constraint(&mut self, constraint: &'ast AssocItemConstraint) {1324 self.visit_ident(&constraint.ident);1325 if let Some(ref gen_args) = constraint.gen_args {1326 // Forbid anonymous lifetimes in GAT parameters until proper semantics are decided.1327 self.with_lifetime_rib(LifetimeRibKind::AnonymousReportError, |this| {1328 this.visit_generic_args(gen_args)1329 });1330 }1331 match constraint.kind {1332 AssocItemConstraintKind::Equality { ref term } => match term {1333 Term::Ty(ty) => {1334 let prev = replace(&mut self.diag_metadata.in_assoc_ty_binding, true);1335 self.visit_ty(ty);1336 self.diag_metadata.in_assoc_ty_binding = prev;1337 }1338 Term::Const(c) => {1339 self.resolve_anon_const(c, AnonConstKind::ConstArg(IsRepeatExpr::No))1340 }1341 },1342 AssocItemConstraintKind::Bound { ref bounds } => {1343 walk_list!(self, visit_param_bound, bounds, BoundKind::Bound);1344 }1345 }1346 }13471348 fn visit_path_segment(&mut self, path_segment: &'ast PathSegment) {1349 let Some(ref args) = path_segment.args else {1350 return;1351 };13521353 match &**args {1354 GenericArgs::AngleBracketed(..) => visit::walk_generic_args(self, args),1355 GenericArgs::Parenthesized(p_args) => {1356 // Probe the lifetime ribs to know how to behave.1357 for rib in self.lifetime_ribs.iter().rev() {1358 match rib.kind {1359 // We are inside a `PolyTraitRef`. The lifetimes are1360 // to be introduced in that (maybe implicit) `for<>` binder.1361 LifetimeRibKind::Generics {1362 binder,1363 kind: LifetimeBinderKind::PolyTrait,1364 ..1365 } => {1366 self.resolve_fn_signature(1367 binder,1368 false,1369 p_args.inputs.iter().map(|ty| (None, &**ty)),1370 &p_args.output,1371 false,1372 );1373 break;1374 }1375 // We have nowhere to introduce generics. Code is malformed,1376 // so use regular lifetime resolution to avoid spurious errors.1377 LifetimeRibKind::Item | LifetimeRibKind::Generics { .. } => {1378 visit::walk_generic_args(self, args);1379 break;1380 }1381 LifetimeRibKind::AnonymousCreateParameter { .. }1382 | LifetimeRibKind::AnonymousReportError1383 | LifetimeRibKind::StaticIfNoLifetimeInScope { .. }1384 | LifetimeRibKind::ImplTrait1385 | LifetimeRibKind::Elided(_)1386 | LifetimeRibKind::ElisionFailure1387 | LifetimeRibKind::ConcreteAnonConst(_)1388 | LifetimeRibKind::ConstParamTy => {}1389 }1390 }1391 }1392 GenericArgs::ParenthesizedElided(_) => {}1393 }1394 }13951396 fn visit_where_predicate(&mut self, p: &'ast WherePredicate) {1397 debug!("visit_where_predicate {:?}", p);1398 let previous_value = replace(&mut self.diag_metadata.current_where_predicate, Some(p));1399 self.with_lifetime_rib(LifetimeRibKind::AnonymousReportError, |this| {1400 if let WherePredicateKind::BoundPredicate(WhereBoundPredicate {1401 bounded_ty,1402 bounds,1403 bound_generic_params,1404 ..1405 }) = &p.kind1406 {1407 let span = p.span.shrink_to_lo().to(bounded_ty.span.shrink_to_lo());1408 this.with_generic_param_rib(1409 bound_generic_params,1410 RibKind::Normal,1411 bounded_ty.id,1412 LifetimeBinderKind::WhereBound,1413 span,1414 |this| {1415 this.visit_generic_params(bound_generic_params, false);1416 this.visit_ty(bounded_ty);1417 for bound in bounds {1418 this.visit_param_bound(bound, BoundKind::Bound)1419 }1420 },1421 );1422 } else {1423 visit::walk_where_predicate(this, p);1424 }1425 });1426 self.diag_metadata.current_where_predicate = previous_value;1427 }14281429 fn visit_inline_asm(&mut self, asm: &'ast InlineAsm) {1430 for (op, _) in &asm.operands {1431 match op {1432 InlineAsmOperand::In { expr, .. }1433 | InlineAsmOperand::Out { expr: Some(expr), .. }1434 | InlineAsmOperand::InOut { expr, .. } => self.visit_expr(expr),1435 InlineAsmOperand::Out { expr: None, .. } => {}1436 InlineAsmOperand::SplitInOut { in_expr, out_expr, .. } => {1437 self.visit_expr(in_expr);1438 if let Some(out_expr) = out_expr {1439 self.visit_expr(out_expr);1440 }1441 }1442 InlineAsmOperand::Const { anon_const, .. } => {1443 // Although this is `DefKind::AnonConst`, it is allowed to reference outer1444 // generic parameters like an inline const.1445 self.resolve_anon_const(anon_const, AnonConstKind::InlineConst);1446 }1447 InlineAsmOperand::Sym { sym } => self.visit_inline_asm_sym(sym),1448 InlineAsmOperand::Label { block } => self.visit_block(block),1449 }1450 }1451 }14521453 fn visit_inline_asm_sym(&mut self, sym: &'ast InlineAsmSym) {1454 // This is similar to the code for AnonConst.1455 self.with_rib(ValueNS, RibKind::InlineAsmSym, |this| {1456 this.with_rib(TypeNS, RibKind::InlineAsmSym, |this| {1457 this.with_label_rib(RibKind::InlineAsmSym, |this| {1458 this.smart_resolve_path(sym.id, &sym.qself, &sym.path, PathSource::Expr(None));1459 visit::walk_inline_asm_sym(this, sym);1460 });1461 })1462 });1463 }14641465 fn visit_variant(&mut self, v: &'ast Variant) {1466 self.resolve_doc_links(&v.attrs, MaybeExported::Ok(v.id));1467 self.visit_id(v.id);1468 walk_list!(self, visit_attribute, &v.attrs);1469 self.visit_vis(&v.vis);1470 self.visit_ident(&v.ident);1471 self.visit_variant_data(&v.data);1472 if let Some(discr) = &v.disr_expr {1473 self.resolve_anon_const(discr, AnonConstKind::EnumDiscriminant);1474 }1475 }14761477 fn visit_field_def(&mut self, f: &'ast FieldDef) {1478 self.resolve_doc_links(&f.attrs, MaybeExported::Ok(f.id));1479 let FieldDef {1480 attrs,1481 id: _,1482 span: _,1483 vis,1484 ident,1485 ty,1486 is_placeholder: _,1487 default,1488 mut_restriction: _,1489 safety: _,1490 } = f;1491 walk_list!(self, visit_attribute, attrs);1492 try_visit!(self.visit_vis(vis));1493 visit_opt!(self, visit_ident, ident);1494 try_visit!(self.visit_ty(ty));1495 if let Some(v) = &default {1496 self.resolve_anon_const(v, AnonConstKind::FieldDefaultValue);1497 }1498 }1499}15001501impl<'a, 'ast, 'ra, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {1502 fn new(resolver: &'a mut Resolver<'ra, 'tcx>) -> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {1503 // During late resolution we only track the module component of the parent scope,1504 // although it may be useful to track other components as well for diagnostics.1505 let graph_root = resolver.graph_root;1506 let parent_scope = ParentScope::module(graph_root, resolver.arenas);1507 let start_rib_kind = RibKind::Module(graph_root);1508 LateResolutionVisitor {1509 r: resolver,1510 parent_scope,1511 ribs: PerNS {1512 value_ns: vec![Rib::new(start_rib_kind)],1513 type_ns: vec![Rib::new(start_rib_kind)],1514 macro_ns: vec![Rib::new(start_rib_kind)],1515 },1516 last_block_rib: None,1517 label_ribs: Vec::new(),1518 lifetime_ribs: Vec::new(),1519 lifetime_elision_candidates: None,1520 current_trait_ref: None,1521 diag_metadata: Default::default(),1522 // errors at module scope should always be reported1523 in_func_body: false,1524 lifetime_uses: Default::default(),1525 }1526 }15271528 fn maybe_resolve_ident_in_lexical_scope(1529 &mut self,1530 ident: Ident,1531 ns: Namespace,1532 ) -> Option<LateDecl<'ra>> {1533 self.r.resolve_ident_in_lexical_scope(1534 ident,1535 ns,1536 &self.parent_scope,1537 None,1538 &self.ribs[ns],1539 None,1540 Some(&self.diag_metadata),1541 )1542 }15431544 fn resolve_ident_in_lexical_scope(1545 &mut self,1546 ident: Ident,1547 ns: Namespace,1548 finalize: Option<Finalize>,1549 ignore_decl: Option<Decl<'ra>>,1550 ) -> Option<LateDecl<'ra>> {1551 self.r.resolve_ident_in_lexical_scope(1552 ident,1553 ns,1554 &self.parent_scope,1555 finalize,1556 &self.ribs[ns],1557 ignore_decl,1558 Some(&self.diag_metadata),1559 )1560 }15611562 fn resolve_path(1563 &mut self,1564 path: &[Segment],1565 opt_ns: Option<Namespace>, // `None` indicates a module path in import1566 finalize: Option<Finalize>,1567 source: PathSource<'_, 'ast, 'ra>,1568 ) -> PathResult<'ra> {1569 self.r.cm().resolve_path_with_ribs(1570 path,1571 opt_ns,1572 &self.parent_scope,1573 Some(source),1574 finalize.map(|finalize| Finalize { stage: Stage::Late, ..finalize }),1575 Some(&self.ribs),1576 None,1577 None,1578 Some(&self.diag_metadata),1579 )1580 }15811582 // AST resolution1583 //1584 // We maintain a list of value ribs and type ribs.1585 //1586 // Simultaneously, we keep track of the current position in the module1587 // graph in the `parent_scope.module` pointer. When we go to resolve a name in1588 // the value or type namespaces, we first look through all the ribs and1589 // then query the module graph. When we resolve a name in the module1590 // namespace, we can skip all the ribs (since nested modules are not1591 // allowed within blocks in Rust) and jump straight to the current module1592 // graph node.1593 //1594 // Named implementations are handled separately. When we find a method1595 // call, we consult the module node to find all of the implementations in1596 // scope. This information is lazily cached in the module node. We then1597 // generate a fake "implementation scope" containing all the1598 // implementations thus found, for compatibility with old resolve pass.15991600 /// Do some `work` within a new innermost rib of the given `kind` in the given namespace (`ns`).1601 fn with_rib<T>(1602 &mut self,1603 ns: Namespace,1604 kind: RibKind<'ra>,1605 work: impl FnOnce(&mut Self) -> T,1606 ) -> T {1607 self.ribs[ns].push(Rib::new(kind));1608 let ret = work(self);1609 self.ribs[ns].pop();1610 ret1611 }16121613 fn visit_generic_params(&mut self, params: &'ast [GenericParam], add_self_upper: bool) {1614 // For type parameter defaults, we have to ban access1615 // to following type parameters, as the GenericArgs can only1616 // provide previous type parameters as they're built. We1617 // put all the parameters on the ban list and then remove1618 // them one by one as they are processed and become available.1619 let mut forward_ty_ban_rib =1620 Rib::new(RibKind::ForwardGenericParamBan(ForwardGenericParamBanReason::Default));1621 let mut forward_const_ban_rib =1622 Rib::new(RibKind::ForwardGenericParamBan(ForwardGenericParamBanReason::Default));1623 for param in params.iter() {1624 match param.kind {1625 GenericParamKind::Type { .. } => {1626 forward_ty_ban_rib1627 .bindings1628 .insert(Ident::with_dummy_span(param.ident.name), Res::Err);1629 }1630 GenericParamKind::Const { .. } => {1631 forward_const_ban_rib1632 .bindings1633 .insert(Ident::with_dummy_span(param.ident.name), Res::Err);1634 }1635 GenericParamKind::Lifetime => {}1636 }1637 }16381639 // rust-lang/rust#61631: The type `Self` is essentially1640 // another type parameter. For ADTs, we consider it1641 // well-defined only after all of the ADT type parameters have1642 // been provided. Therefore, we do not allow use of `Self`1643 // anywhere in ADT type parameter defaults.1644 //1645 // (We however cannot ban `Self` for defaults on *all* generic1646 // lists; e.g. trait generics can usefully refer to `Self`,1647 // such as in the case of `trait Add<Rhs = Self>`.)1648 if add_self_upper {1649 // (`Some` if + only if we are in ADT's generics.)1650 forward_ty_ban_rib.bindings.insert(Ident::with_dummy_span(kw::SelfUpper), Res::Err);1651 }16521653 // NOTE: We use different ribs here not for a technical reason, but just1654 // for better diagnostics.1655 let mut forward_ty_ban_rib_const_param_ty = Rib {1656 bindings: forward_ty_ban_rib.bindings.clone(),1657 patterns_with_skipped_bindings: Default::default(),1658 kind: RibKind::ForwardGenericParamBan(ForwardGenericParamBanReason::ConstParamTy),1659 };1660 let mut forward_const_ban_rib_const_param_ty = Rib {1661 bindings: forward_const_ban_rib.bindings.clone(),1662 patterns_with_skipped_bindings: Default::default(),1663 kind: RibKind::ForwardGenericParamBan(ForwardGenericParamBanReason::ConstParamTy),1664 };1665 // We'll ban these with a `ConstParamTy` rib, so just clear these ribs for better1666 // diagnostics, so we don't mention anything about const param tys having generics at all.1667 if !self.r.tcx.features().generic_const_parameter_types() {1668 forward_ty_ban_rib_const_param_ty.bindings.clear();1669 forward_const_ban_rib_const_param_ty.bindings.clear();1670 }16711672 self.with_lifetime_rib(LifetimeRibKind::AnonymousReportError, |this| {1673 for param in params {1674 match param.kind {1675 GenericParamKind::Lifetime => {1676 for bound in ¶m.bounds {1677 this.visit_param_bound(bound, BoundKind::Bound);1678 }1679 }1680 GenericParamKind::Type { ref default } => {1681 for bound in ¶m.bounds {1682 this.visit_param_bound(bound, BoundKind::Bound);1683 }16841685 if let Some(ty) = default {1686 this.ribs[TypeNS].push(forward_ty_ban_rib);1687 this.ribs[ValueNS].push(forward_const_ban_rib);1688 this.visit_ty(ty);1689 forward_const_ban_rib = this.ribs[ValueNS].pop().unwrap();1690 forward_ty_ban_rib = this.ribs[TypeNS].pop().unwrap();1691 }16921693 // Allow all following defaults to refer to this type parameter.1694 let i = &Ident::with_dummy_span(param.ident.name);1695 forward_ty_ban_rib.bindings.swap_remove(i);1696 forward_ty_ban_rib_const_param_ty.bindings.swap_remove(i);1697 }1698 GenericParamKind::Const { ref ty, span: _, ref default } => {1699 // Const parameters can't have param bounds.1700 assert!(param.bounds.is_empty());17011702 this.ribs[TypeNS].push(forward_ty_ban_rib_const_param_ty);1703 this.ribs[ValueNS].push(forward_const_ban_rib_const_param_ty);1704 if this.r.tcx.features().generic_const_parameter_types() {1705 this.visit_ty(ty)1706 } else {1707 this.ribs[TypeNS].push(Rib::new(RibKind::ConstParamTy));1708 this.ribs[ValueNS].push(Rib::new(RibKind::ConstParamTy));1709 this.with_lifetime_rib(LifetimeRibKind::ConstParamTy, |this| {1710 this.visit_ty(ty)1711 });1712 this.ribs[TypeNS].pop().unwrap();1713 this.ribs[ValueNS].pop().unwrap();1714 }1715 forward_const_ban_rib_const_param_ty = this.ribs[ValueNS].pop().unwrap();1716 forward_ty_ban_rib_const_param_ty = this.ribs[TypeNS].pop().unwrap();17171718 if let Some(expr) = default {1719 this.ribs[TypeNS].push(forward_ty_ban_rib);1720 this.ribs[ValueNS].push(forward_const_ban_rib);1721 this.resolve_anon_const(1722 expr,1723 AnonConstKind::ConstArg(IsRepeatExpr::No),1724 );1725 forward_const_ban_rib = this.ribs[ValueNS].pop().unwrap();1726 forward_ty_ban_rib = this.ribs[TypeNS].pop().unwrap();1727 }17281729 // Allow all following defaults to refer to this const parameter.1730 let i = &Ident::with_dummy_span(param.ident.name);1731 forward_const_ban_rib.bindings.swap_remove(i);1732 forward_const_ban_rib_const_param_ty.bindings.swap_remove(i);1733 }1734 }1735 }1736 })1737 }17381739 #[instrument(level = "debug", skip(self, work))]1740 fn with_lifetime_rib<T>(1741 &mut self,1742 kind: LifetimeRibKind,1743 work: impl FnOnce(&mut Self) -> T,1744 ) -> T {1745 self.lifetime_ribs.push(LifetimeRib::new(kind));1746 let outer_elision_candidates = self.lifetime_elision_candidates.take();1747 let ret = work(self);1748 self.lifetime_elision_candidates = outer_elision_candidates;1749 self.lifetime_ribs.pop();1750 ret1751 }17521753 #[instrument(level = "debug", skip(self))]1754 fn resolve_lifetime(&mut self, lifetime: &'ast Lifetime, use_ctxt: visit::LifetimeCtxt) {1755 let ident = lifetime.ident;17561757 if ident.name == kw::StaticLifetime {1758 self.record_lifetime_use(1759 lifetime.id,1760 LifetimeRes::Static,1761 LifetimeElisionCandidate::Ignore,1762 );1763 return;1764 }17651766 if ident.name == kw::UnderscoreLifetime {1767 return self.resolve_anonymous_lifetime(lifetime, lifetime.id, false);1768 }17691770 let mut lifetime_rib_iter = self.lifetime_ribs.iter().rev();1771 while let Some(rib) = lifetime_rib_iter.next() {1772 let normalized_ident = ident.normalize_to_macros_2_0();1773 if let Some(&(_, res)) = rib.bindings.get(&normalized_ident) {1774 self.record_lifetime_use(lifetime.id, res, LifetimeElisionCandidate::Ignore);17751776 if let LifetimeRes::Param { param, binder } = res {1777 match self.lifetime_uses.entry(param) {1778 Entry::Vacant(v) => {1779 debug!("First use of {:?} at {:?}", res, ident.span);1780 let use_set = self1781 .lifetime_ribs1782 .iter()1783 .rev()1784 .find_map(|rib| match rib.kind {1785 // Do not suggest eliding a lifetime where an anonymous1786 // lifetime would be illegal.1787 LifetimeRibKind::Item1788 | LifetimeRibKind::AnonymousReportError1789 | LifetimeRibKind::StaticIfNoLifetimeInScope { .. }1790 | LifetimeRibKind::ElisionFailure => Some(LifetimeUseSet::Many),1791 // An anonymous lifetime is legal here, and bound to the right1792 // place, go ahead.1793 LifetimeRibKind::AnonymousCreateParameter {1794 binder: anon_binder,1795 ..1796 } => Some(if binder == anon_binder {1797 LifetimeUseSet::One { use_span: ident.span, use_ctxt }1798 } else {1799 LifetimeUseSet::Many1800 }),1801 // Only report if eliding the lifetime would have the same1802 // semantics.1803 LifetimeRibKind::Elided(r) => Some(if res == r {1804 LifetimeUseSet::One { use_span: ident.span, use_ctxt }1805 } else {1806 LifetimeUseSet::Many1807 }),1808 LifetimeRibKind::Generics { .. }1809 | LifetimeRibKind::ConstParamTy => None,1810 LifetimeRibKind::ConcreteAnonConst(_) => {1811 span_bug!(ident.span, "unexpected rib kind: {:?}", rib.kind)1812 }18131814 LifetimeRibKind::ImplTrait => {1815 if self.r.tcx.features().anonymous_lifetime_in_impl_trait()1816 {1817 None1818 } else {1819 Some(LifetimeUseSet::Many)1820 }1821 }1822 })1823 .unwrap_or(LifetimeUseSet::Many);1824 debug!(?use_ctxt, ?use_set);1825 v.insert(use_set);1826 }1827 Entry::Occupied(mut o) => {1828 debug!("Many uses of {:?} at {:?}", res, ident.span);1829 *o.get_mut() = LifetimeUseSet::Many;1830 }1831 }1832 }1833 return;1834 }18351836 match rib.kind {1837 LifetimeRibKind::Item => break,1838 LifetimeRibKind::ConstParamTy => {1839 let guar = self.emit_non_static_lt_in_const_param_ty_error(lifetime);1840 self.record_lifetime_err(lifetime.id, guar);1841 return;1842 }1843 LifetimeRibKind::ConcreteAnonConst(cause) => {1844 let guar = self.emit_forbidden_non_static_lifetime_error(cause, lifetime);1845 self.record_lifetime_err(lifetime.id, guar);1846 return;1847 }1848 LifetimeRibKind::AnonymousCreateParameter { .. }1849 | LifetimeRibKind::Elided(_)1850 | LifetimeRibKind::Generics { .. }1851 | LifetimeRibKind::ElisionFailure1852 | LifetimeRibKind::AnonymousReportError1853 | LifetimeRibKind::ImplTrait1854 | LifetimeRibKind::StaticIfNoLifetimeInScope { .. } => {}1855 }1856 }18571858 let normalized_ident = ident.normalize_to_macros_2_0();1859 let outer_res = lifetime_rib_iter1860 .find_map(|rib| rib.bindings.get_key_value(&normalized_ident).map(|(&outer, _)| outer));18611862 let guar = self.emit_undeclared_lifetime_error(lifetime, outer_res);1863 self.record_lifetime_err(lifetime.id, guar);1864 }18651866 #[instrument(level = "debug", skip(self))]1867 fn resolve_anonymous_lifetime(1868 &mut self,1869 lifetime: &Lifetime,1870 id_for_lint: NodeId,1871 elided: bool,1872 ) {1873 debug_assert_eq!(lifetime.ident.name, kw::UnderscoreLifetime);18741875 let kind =1876 if elided { MissingLifetimeKind::Ampersand } else { MissingLifetimeKind::Underscore };1877 let missing_lifetime = MissingLifetime {1878 id: lifetime.id,1879 span: lifetime.ident.span,1880 kind,1881 count: 1,1882 id_for_lint,1883 };1884 let elision_candidate = LifetimeElisionCandidate::Missing(missing_lifetime);1885 for (i, rib) in self.lifetime_ribs.iter().enumerate().rev() {1886 debug!(?rib.kind);1887 match rib.kind {1888 LifetimeRibKind::AnonymousCreateParameter { binder, .. } => {1889 let res = self.create_fresh_lifetime(lifetime.ident, binder, kind);1890 self.record_lifetime_use(lifetime.id, res, elision_candidate);1891 return;1892 }1893 LifetimeRibKind::StaticIfNoLifetimeInScope { lint_id: node_id, emit_lint } => {1894 let mut lifetimes_in_scope = vec![];1895 for rib in self.lifetime_ribs[..i].iter().rev() {1896 lifetimes_in_scope.extend(rib.bindings.iter().map(|(ident, _)| ident.span));1897 // Consider any anonymous lifetimes, too1898 if let LifetimeRibKind::AnonymousCreateParameter { binder, .. } = rib.kind1899 && let Some(extra) = self.r.extra_lifetime_params_map.get(&binder)1900 {1901 lifetimes_in_scope.extend(extra.iter().map(|(ident, _, _)| ident.span));1902 }1903 if let LifetimeRibKind::Item = rib.kind {1904 break;1905 }1906 }1907 if lifetimes_in_scope.is_empty() {1908 self.record_lifetime_use(1909 lifetime.id,1910 LifetimeRes::Static,1911 elision_candidate,1912 );1913 return;1914 } else if emit_lint {1915 let lt_span = if elided {1916 lifetime.ident.span.shrink_to_hi()1917 } else {1918 lifetime.ident.span1919 };1920 let code = if elided { "'static " } else { "'static" };19211922 self.r.lint_buffer.buffer_lint(1923 lint::builtin::ELIDED_LIFETIMES_IN_ASSOCIATED_CONSTANT,1924 node_id,1925 lifetime.ident.span,1926 crate::diagnostics::AssociatedConstElidedLifetime {1927 elided,1928 code,1929 span: lt_span,1930 lifetimes_in_scope: lifetimes_in_scope.into(),1931 },1932 );1933 }1934 }1935 LifetimeRibKind::AnonymousReportError => {1936 let guar = if elided {1937 let suggestion = if self.diag_metadata.in_assoc_ty_binding {1938 // In an associated type binding like `I: IntoIterator<Item = &T>`,1939 // introducing the lifetime on the trait ref would produce1940 // `I: for<'a> IntoIterator<Item = &'a T>`. Prefer a named lifetime1941 // from an enclosing item instead, so the assoc-ty-binding-specific path1942 // below builds that suggestion.1943 None1944 } else {1945 self.lifetime_ribs[i..].iter().rev().find_map(|rib| {1946 // Look for a `Generics` rib that represents a trait or where-bound1947 // binder (`T: Trait<&U>` or `where T: Trait<&U>`), since that is1948 // where the generic E0637 diagnostic can insert `for<'a>`.1949 if let LifetimeRibKind::Generics {1950 span,1951 kind:1952 LifetimeBinderKind::PolyTrait1953 | LifetimeBinderKind::WhereBound,1954 ..1955 } = rib.kind1956 {1957 Some(crate::diagnostics::ElidedAnonymousLifetimeReportErrorSuggestion {1958 lo: span.shrink_to_lo(),1959 hi: lifetime.ident.span.shrink_to_hi(),1960 })1961 } else {1962 None1963 }1964 })1965 };1966 // are we trying to use an anonymous lifetime1967 // on a non GAT associated trait type?1968 if !self.in_func_body1969 && let Some((module, _)) = &self.current_trait_ref1970 && let Some(ty) = &self.diag_metadata.current_self_type1971 && Some(true) == self.diag_metadata.in_non_gat_assoc_type1972 && let crate::ModuleKind::Def(DefKind::Trait, trait_id, _, _) =1973 module.kind1974 {1975 if def_id_matches_path(1976 self.r.tcx,1977 trait_id,1978 &["core", "iter", "traits", "iterator", "Iterator"],1979 ) {1980 self.r.dcx().emit_err(1981 crate::diagnostics::LendingIteratorReportError {1982 lifetime: lifetime.ident.span,1983 ty: ty.span,1984 },1985 )1986 } else {1987 let decl = if !trait_id.is_local()1988 && let Some(assoc) = self.diag_metadata.current_impl_item1989 && let AssocItemKind::Type(_) = assoc.kind1990 && let assocs = self.r.tcx.associated_items(trait_id)1991 && let Some(ident) = assoc.kind.ident()1992 && let Some(assoc) = assocs.find_by_ident_and_kind(1993 self.r.tcx,1994 ident,1995 AssocTag::Type,1996 trait_id,1997 ) {1998 let mut decl: MultiSpan =1999 self.r.tcx.def_span(assoc.def_id).into();2000 decl.push_span_label(
Findings
✓ No findings reported for this file.