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, TraitCandidate};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, errors, path_names_to_string, rustdoc,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(r.local_def_id(node_id)),696 MaybeExported::Impl(Some(trait_def_id)) | MaybeExported::ImplItem(Ok(trait_def_id)) => {697 trait_def_id.as_local()698 }699 MaybeExported::Impl(None) => return true,700 MaybeExported::ImplItem(Err(vis)) | MaybeExported::NestedUse(vis) => {701 return vis.kind.is_pub();702 }703 };704 def_id.is_none_or(|def_id| r.effective_visibilities.is_exported(def_id))705 }706}707708/// Used for recording UnnecessaryQualification.709#[derive(Debug)]710pub(crate) struct UnnecessaryQualification<'ra> {711 pub decl: LateDecl<'ra>,712 pub node_id: NodeId,713 pub path_span: Span,714 pub removal_span: Span,715}716717#[derive(Default, Debug)]718pub(crate) struct DiagMetadata<'ast> {719 /// The current trait's associated items' ident, used for diagnostic suggestions.720 current_trait_assoc_items: Option<&'ast [Box<AssocItem>]>,721722 /// The current self type if inside an impl (used for better errors).723 pub(crate) current_self_type: Option<Ty>,724725 /// The current self item if inside an ADT (used for better errors).726 current_self_item: Option<NodeId>,727728 /// The current item being evaluated (used for suggestions and more detail in errors).729 pub(crate) current_item: Option<&'ast Item>,730731 /// When processing generic arguments and encountering an unresolved ident not found,732 /// suggest introducing a type or const param depending on the context.733 currently_processing_generic_args: bool,734735 /// The current enclosing (non-closure) function (used for better errors).736 current_function: Option<(FnKind<'ast>, Span)>,737738 /// A list of labels as of yet unused. Labels will be removed from this map when739 /// they are used (in a `break` or `continue` statement)740 unused_labels: FxIndexMap<NodeId, Span>,741742 /// Only used for better errors on `let <pat>: <expr, not type>;`.743 current_let_binding: Option<(Span, Option<Span>, Option<Span>)>,744745 current_pat: Option<&'ast Pat>,746747 /// Used to detect possible `if let` written without `let` and to provide structured suggestion.748 in_if_condition: Option<&'ast Expr>,749750 /// Used to detect possible new binding written without `let` and to provide structured suggestion.751 in_assignment: Option<&'ast Expr>,752 is_assign_rhs: bool,753754 /// If we are setting an associated type in trait impl, is it a non-GAT type?755 in_non_gat_assoc_type: Option<bool>,756757 /// Used to detect possible `.` -> `..` typo when calling methods.758 in_range: Option<(&'ast Expr, &'ast Expr)>,759760 /// If we are currently in a trait object definition. Used to point at the bounds when761 /// encountering a struct or enum.762 current_trait_object: Option<&'ast [ast::GenericBound]>,763764 /// Given `where <T as Bar>::Baz: String`, suggest `where T: Bar<Baz = String>`.765 current_where_predicate: Option<&'ast WherePredicate>,766767 current_type_path: Option<&'ast Ty>,768769 /// The current impl items (used to suggest).770 current_impl_items: Option<&'ast [Box<AssocItem>]>,771772 /// The current impl items (used to suggest).773 current_impl_item: Option<&'ast AssocItem>,774775 /// When processing impl trait776 currently_processing_impl_trait: Option<(TraitRef, Ty)>,777778 /// Accumulate the errors due to missed lifetime elision,779 /// and report them all at once for each function.780 current_elision_failures:781 Vec<(MissingLifetime, LifetimeElisionCandidate, Either<NodeId, Range<NodeId>>)>,782}783784struct LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {785 r: &'a mut Resolver<'ra, 'tcx>,786787 /// The module that represents the current item scope.788 parent_scope: ParentScope<'ra>,789790 /// The current set of local scopes for types and values.791 ribs: PerNS<Vec<Rib<'ra>>>,792793 /// Previous popped `rib`, only used for diagnostic.794 last_block_rib: Option<Rib<'ra>>,795796 /// The current set of local scopes, for labels.797 label_ribs: Vec<Rib<'ra, NodeId>>,798799 /// The current set of local scopes for lifetimes.800 lifetime_ribs: Vec<LifetimeRib>,801802 /// We are looking for lifetimes in an elision context.803 /// The set contains all the resolutions that we encountered so far.804 /// They will be used to determine the correct lifetime for the fn return type.805 /// The `LifetimeElisionCandidate` is used for diagnostics, to suggest introducing named806 /// lifetimes.807 lifetime_elision_candidates: Option<Vec<(LifetimeRes, LifetimeElisionCandidate)>>,808809 /// The trait that the current context can refer to.810 current_trait_ref: Option<(Module<'ra>, TraitRef)>,811812 /// Fields used to add information to diagnostic errors.813 diag_metadata: Box<DiagMetadata<'ast>>,814815 /// State used to know whether to ignore resolution errors for function bodies.816 ///817 /// In particular, rustdoc uses this to avoid giving errors for `cfg()` items.818 /// In most cases this will be `None`, in which case errors will always be reported.819 /// If it is `true`, then it will be updated when entering a nested function or trait body.820 in_func_body: bool,821822 /// Count the number of places a lifetime is used.823 lifetime_uses: FxHashMap<LocalDefId, LifetimeUseSet>,824}825826/// Walks the whole crate in DFS order, visiting each item, resolving names as it goes.827impl<'ast, 'ra, 'tcx> Visitor<'ast> for LateResolutionVisitor<'_, 'ast, 'ra, 'tcx> {828 fn visit_attribute(&mut self, _: &'ast Attribute) {829 // We do not want to resolve expressions that appear in attributes,830 // as they do not correspond to actual code.831 }832 fn visit_item(&mut self, item: &'ast Item) {833 let prev = replace(&mut self.diag_metadata.current_item, Some(item));834 // Always report errors in items we just entered.835 let old_ignore = replace(&mut self.in_func_body, false);836 self.with_lifetime_rib(LifetimeRibKind::Item, |this| this.resolve_item(item));837 self.in_func_body = old_ignore;838 self.diag_metadata.current_item = prev;839 }840 fn visit_arm(&mut self, arm: &'ast Arm) {841 self.resolve_arm(arm);842 }843 fn visit_block(&mut self, block: &'ast Block) {844 let old_macro_rules = self.parent_scope.macro_rules;845 self.resolve_block(block);846 self.parent_scope.macro_rules = old_macro_rules;847 }848 fn visit_anon_const(&mut self, constant: &'ast AnonConst) {849 bug!("encountered anon const without a manual call to `resolve_anon_const`: {constant:#?}");850 }851 fn visit_expr(&mut self, expr: &'ast Expr) {852 self.resolve_expr(expr, None);853 }854 fn visit_pat(&mut self, p: &'ast Pat) {855 let prev = self.diag_metadata.current_pat;856 self.diag_metadata.current_pat = Some(p);857858 if let PatKind::Guard(subpat, _) = &p.kind {859 // We walk the guard expression in `resolve_pattern_inner`. Don't resolve it twice.860 self.visit_pat(subpat);861 } else {862 visit::walk_pat(self, p);863 }864865 self.diag_metadata.current_pat = prev;866 }867 fn visit_local(&mut self, local: &'ast Local) {868 let local_spans = match local.pat.kind {869 // We check for this to avoid tuple struct fields.870 PatKind::Wild => None,871 _ => Some((872 local.pat.span,873 local.ty.as_ref().map(|ty| ty.span),874 local.kind.init().map(|init| init.span),875 )),876 };877 let original = replace(&mut self.diag_metadata.current_let_binding, local_spans);878 self.resolve_local(local);879 self.diag_metadata.current_let_binding = original;880 }881 fn visit_ty(&mut self, ty: &'ast Ty) {882 let prev = self.diag_metadata.current_trait_object;883 let prev_ty = self.diag_metadata.current_type_path;884 match &ty.kind {885 TyKind::Ref(None, _) | TyKind::PinnedRef(None, _) => {886 // Elided lifetime in reference: we resolve as if there was some lifetime `'_` with887 // NodeId `ty.id`.888 // This span will be used in case of elision failure.889 let span = self.r.tcx.sess.source_map().start_point(ty.span);890 self.resolve_elided_lifetime(ty.id, span);891 visit::walk_ty(self, ty);892 }893 TyKind::Path(qself, path) => {894 self.diag_metadata.current_type_path = Some(ty);895896 // If we have a path that ends with `(..)`, then it must be897 // return type notation. Resolve that path in the *value*898 // namespace.899 let source = if let Some(seg) = path.segments.last()900 && let Some(args) = &seg.args901 && matches!(**args, GenericArgs::ParenthesizedElided(..))902 {903 PathSource::ReturnTypeNotation904 } else {905 PathSource::Type906 };907908 self.smart_resolve_path(ty.id, qself, path, source);909910 // Check whether we should interpret this as a bare trait object.911 if qself.is_none()912 && let Some(partial_res) = self.r.partial_res_map.get(&ty.id)913 && let Some(Res::Def(DefKind::Trait | DefKind::TraitAlias, _)) =914 partial_res.full_res()915 {916 // This path is actually a bare trait object. In case of a bare `Fn`-trait917 // object with anonymous lifetimes, we need this rib to correctly place the918 // synthetic lifetimes.919 let span = ty.span.shrink_to_lo().to(path.span.shrink_to_lo());920 self.with_generic_param_rib(921 &[],922 RibKind::Normal,923 ty.id,924 LifetimeBinderKind::PolyTrait,925 span,926 |this| this.visit_path(path),927 );928 } else {929 visit::walk_ty(self, ty)930 }931 }932 TyKind::ImplicitSelf => {933 let self_ty = Ident::with_dummy_span(kw::SelfUpper);934 let res = self935 .resolve_ident_in_lexical_scope(936 self_ty,937 TypeNS,938 Some(Finalize::new(ty.id, ty.span)),939 None,940 )941 .map_or(Res::Err, |d| d.res());942 self.r.record_partial_res(ty.id, PartialRes::new(res));943 visit::walk_ty(self, ty)944 }945 TyKind::ImplTrait(..) => {946 let candidates = self.lifetime_elision_candidates.take();947 self.with_lifetime_rib(LifetimeRibKind::ImplTrait, |this| visit::walk_ty(this, ty));948 self.lifetime_elision_candidates = candidates;949 }950 TyKind::TraitObject(bounds, ..) => {951 self.diag_metadata.current_trait_object = Some(&bounds[..]);952 visit::walk_ty(self, ty)953 }954 TyKind::FnPtr(fn_ptr) => {955 let span = ty.span.shrink_to_lo().to(fn_ptr.decl_span.shrink_to_lo());956 self.with_generic_param_rib(957 &fn_ptr.generic_params,958 RibKind::Normal,959 ty.id,960 LifetimeBinderKind::FnPtrType,961 span,962 |this| {963 this.visit_generic_params(&fn_ptr.generic_params, false);964 this.resolve_fn_signature(965 ty.id,966 false,967 // We don't need to deal with patterns in parameters, because968 // they are not possible for foreign or bodiless functions.969 fn_ptr.decl.inputs.iter().map(|Param { ty, .. }| (None, &**ty)),970 &fn_ptr.decl.output,971 false,972 )973 },974 )975 }976 TyKind::UnsafeBinder(unsafe_binder) => {977 let span = ty.span.shrink_to_lo().to(unsafe_binder.inner_ty.span.shrink_to_lo());978 self.with_generic_param_rib(979 &unsafe_binder.generic_params,980 RibKind::Normal,981 ty.id,982 LifetimeBinderKind::FnPtrType,983 span,984 |this| {985 this.visit_generic_params(&unsafe_binder.generic_params, false);986 this.with_lifetime_rib(987 // We don't allow anonymous `unsafe &'_ ()` binders,988 // although I guess we could.989 LifetimeRibKind::AnonymousReportError,990 |this| this.visit_ty(&unsafe_binder.inner_ty),991 );992 },993 )994 }995 TyKind::Array(element_ty, length) => {996 self.visit_ty(element_ty);997 self.resolve_anon_const(length, AnonConstKind::ConstArg(IsRepeatExpr::No));998 }999 _ => visit::walk_ty(self, ty),1000 }1001 self.diag_metadata.current_trait_object = prev;1002 self.diag_metadata.current_type_path = prev_ty;1003 }10041005 fn visit_ty_pat(&mut self, t: &'ast TyPat) -> Self::Result {1006 match &t.kind {1007 TyPatKind::Range(start, end, _) => {1008 if let Some(start) = start {1009 self.resolve_anon_const(start, AnonConstKind::ConstArg(IsRepeatExpr::No));1010 }1011 if let Some(end) = end {1012 self.resolve_anon_const(end, AnonConstKind::ConstArg(IsRepeatExpr::No));1013 }1014 }1015 TyPatKind::Or(patterns) => {1016 for pat in patterns {1017 self.visit_ty_pat(pat)1018 }1019 }1020 TyPatKind::NotNull | TyPatKind::Err(_) => {}1021 }1022 }10231024 fn visit_poly_trait_ref(&mut self, tref: &'ast PolyTraitRef) {1025 let span = tref.span.shrink_to_lo().to(tref.trait_ref.path.span.shrink_to_lo());1026 self.with_generic_param_rib(1027 &tref.bound_generic_params,1028 RibKind::Normal,1029 tref.trait_ref.ref_id,1030 LifetimeBinderKind::PolyTrait,1031 span,1032 |this| {1033 this.visit_generic_params(&tref.bound_generic_params, false);1034 this.smart_resolve_path(1035 tref.trait_ref.ref_id,1036 &None,1037 &tref.trait_ref.path,1038 PathSource::Trait(AliasPossibility::Maybe),1039 );1040 this.visit_trait_ref(&tref.trait_ref);1041 },1042 );1043 }1044 fn visit_foreign_item(&mut self, foreign_item: &'ast ForeignItem) {1045 self.resolve_doc_links(&foreign_item.attrs, MaybeExported::Ok(foreign_item.id));1046 let def_kind = self.r.local_def_kind(foreign_item.id);1047 match foreign_item.kind {1048 ForeignItemKind::TyAlias(box TyAlias { ref generics, .. }) => {1049 self.with_generic_param_rib(1050 &generics.params,1051 RibKind::Item(HasGenericParams::Yes(generics.span), def_kind),1052 foreign_item.id,1053 LifetimeBinderKind::Item,1054 generics.span,1055 |this| visit::walk_item(this, foreign_item),1056 );1057 }1058 ForeignItemKind::Fn(box Fn { ref generics, .. }) => {1059 self.with_generic_param_rib(1060 &generics.params,1061 RibKind::Item(HasGenericParams::Yes(generics.span), def_kind),1062 foreign_item.id,1063 LifetimeBinderKind::Function,1064 generics.span,1065 |this| visit::walk_item(this, foreign_item),1066 );1067 }1068 ForeignItemKind::Static(..) => {1069 self.with_static_rib(def_kind, |this| visit::walk_item(this, foreign_item))1070 }1071 ForeignItemKind::MacCall(..) => {1072 panic!("unexpanded macro in resolve!")1073 }1074 }1075 }1076 fn visit_fn(&mut self, fn_kind: FnKind<'ast>, _: &AttrVec, sp: Span, fn_id: NodeId) {1077 let previous_value = self.diag_metadata.current_function;1078 match fn_kind {1079 // Bail if the function is foreign, and thus cannot validly have1080 // a body, or if there's no body for some other reason.1081 FnKind::Fn(FnCtxt::Foreign, _, Fn { sig, ident, generics, .. })1082 | FnKind::Fn(_, _, Fn { sig, ident, generics, body: None, .. }) => {1083 self.visit_fn_header(&sig.header);1084 self.visit_ident(ident);1085 self.visit_generics(generics);1086 self.resolve_fn_signature(1087 fn_id,1088 sig.decl.has_self(),1089 sig.decl.inputs.iter().map(|Param { ty, .. }| (None, &**ty)),1090 &sig.decl.output,1091 false,1092 );1093 return;1094 }1095 FnKind::Fn(..) => {1096 self.diag_metadata.current_function = Some((fn_kind, sp));1097 }1098 // Do not update `current_function` for closures: it suggests `self` parameters.1099 FnKind::Closure(..) => {}1100 };1101 debug!("(resolving function) entering function");11021103 if let FnKind::Fn(_, _, f) = fn_kind {1104 self.resolve_eii(&f.eii_impls);1105 }11061107 // Create a value rib for the function.1108 self.with_rib(ValueNS, RibKind::FnOrCoroutine, |this| {1109 // Create a label rib for the function.1110 this.with_label_rib(RibKind::FnOrCoroutine, |this| {1111 match fn_kind {1112 FnKind::Fn(_, _, Fn { sig, generics, contract, body, .. }) => {1113 this.visit_generics(generics);11141115 let declaration = &sig.decl;1116 let coro_node_id = sig1117 .header1118 .coroutine_kind1119 .map(|coroutine_kind| coroutine_kind.return_id());11201121 this.resolve_fn_signature(1122 fn_id,1123 declaration.has_self(),1124 declaration1125 .inputs1126 .iter()1127 .map(|Param { pat, ty, .. }| (Some(&**pat), &**ty)),1128 &declaration.output,1129 coro_node_id.is_some(),1130 );11311132 if let Some(contract) = contract {1133 this.visit_contract(contract);1134 }11351136 if let Some(body) = body {1137 // Ignore errors in function bodies if this is rustdoc1138 // Be sure not to set this until the function signature has been resolved.1139 let previous_state = replace(&mut this.in_func_body, true);1140 // We only care block in the same function1141 this.last_block_rib = None;1142 // Resolve the function body, potentially inside the body of an async closure1143 this.with_lifetime_rib(1144 LifetimeRibKind::Elided(LifetimeRes::Infer),1145 |this| this.visit_block(body),1146 );11471148 debug!("(resolving function) leaving function");1149 this.in_func_body = previous_state;1150 }1151 }1152 FnKind::Closure(binder, _, declaration, body) => {1153 this.visit_closure_binder(binder);11541155 this.with_lifetime_rib(1156 match binder {1157 // We do not have any explicit generic lifetime parameter.1158 ClosureBinder::NotPresent => {1159 LifetimeRibKind::AnonymousCreateParameter {1160 binder: fn_id,1161 report_in_path: false,1162 }1163 }1164 ClosureBinder::For { .. } => LifetimeRibKind::AnonymousReportError,1165 },1166 // Add each argument to the rib.1167 |this| this.resolve_params(&declaration.inputs),1168 );1169 this.with_lifetime_rib(1170 match binder {1171 ClosureBinder::NotPresent => {1172 LifetimeRibKind::Elided(LifetimeRes::Infer)1173 }1174 ClosureBinder::For { .. } => LifetimeRibKind::AnonymousReportError,1175 },1176 |this| visit::walk_fn_ret_ty(this, &declaration.output),1177 );11781179 // Ignore errors in function bodies if this is rustdoc1180 // Be sure not to set this until the function signature has been resolved.1181 let previous_state = replace(&mut this.in_func_body, true);1182 // Resolve the function body, potentially inside the body of an async closure1183 this.with_lifetime_rib(1184 LifetimeRibKind::Elided(LifetimeRes::Infer),1185 |this| this.visit_expr(body),1186 );11871188 debug!("(resolving function) leaving function");1189 this.in_func_body = previous_state;1190 }1191 }1192 })1193 });1194 self.diag_metadata.current_function = previous_value;1195 }11961197 fn visit_lifetime(&mut self, lifetime: &'ast Lifetime, use_ctxt: visit::LifetimeCtxt) {1198 self.resolve_lifetime(lifetime, use_ctxt)1199 }12001201 fn visit_precise_capturing_arg(&mut self, arg: &'ast PreciseCapturingArg) {1202 match arg {1203 // Lower the lifetime regularly; we'll resolve the lifetime and check1204 // it's a parameter later on in HIR lowering.1205 PreciseCapturingArg::Lifetime(_) => {}12061207 PreciseCapturingArg::Arg(path, id) => {1208 // we want `impl use<C>` to try to resolve `C` as both a type parameter or1209 // a const parameter. Since the resolver specifically doesn't allow having1210 // two generic params with the same name, even if they're a different namespace,1211 // it doesn't really matter which we try resolving first, but just like1212 // `Ty::Param` we just fall back to the value namespace only if it's missing1213 // from the type namespace.1214 let mut check_ns = |ns| {1215 self.maybe_resolve_ident_in_lexical_scope(path.segments[0].ident, ns).is_some()1216 };1217 // Like `Ty::Param`, we try resolving this as both a const and a type.1218 if !check_ns(TypeNS) && check_ns(ValueNS) {1219 self.smart_resolve_path(1220 *id,1221 &None,1222 path,1223 PathSource::PreciseCapturingArg(ValueNS),1224 );1225 } else {1226 self.smart_resolve_path(1227 *id,1228 &None,1229 path,1230 PathSource::PreciseCapturingArg(TypeNS),1231 );1232 }1233 }1234 }12351236 visit::walk_precise_capturing_arg(self, arg)1237 }12381239 fn visit_generics(&mut self, generics: &'ast Generics) {1240 self.visit_generic_params(&generics.params, self.diag_metadata.current_self_item.is_some());1241 for p in &generics.where_clause.predicates {1242 self.visit_where_predicate(p);1243 }1244 }12451246 fn visit_closure_binder(&mut self, b: &'ast ClosureBinder) {1247 match b {1248 ClosureBinder::NotPresent => {}1249 ClosureBinder::For { generic_params, .. } => {1250 self.visit_generic_params(1251 generic_params,1252 self.diag_metadata.current_self_item.is_some(),1253 );1254 }1255 }1256 }12571258 fn visit_generic_arg(&mut self, arg: &'ast GenericArg) {1259 debug!("visit_generic_arg({:?})", arg);1260 let prev = replace(&mut self.diag_metadata.currently_processing_generic_args, true);1261 match arg {1262 GenericArg::Type(ty) => {1263 // We parse const arguments as path types as we cannot distinguish them during1264 // parsing. We try to resolve that ambiguity by attempting resolution the type1265 // namespace first, and if that fails we try again in the value namespace. If1266 // resolution in the value namespace succeeds, we have an generic const argument on1267 // our hands.1268 if let TyKind::Path(None, ref path) = ty.kind1269 // We cannot disambiguate multi-segment paths right now as that requires type1270 // checking.1271 && path.is_potential_trivial_const_arg()1272 {1273 let mut check_ns = |ns| {1274 self.maybe_resolve_ident_in_lexical_scope(path.segments[0].ident, ns)1275 .is_some()1276 };1277 if !check_ns(TypeNS) && check_ns(ValueNS) {1278 self.resolve_anon_const_manual(1279 true,1280 AnonConstKind::ConstArg(IsRepeatExpr::No),1281 |this| {1282 this.smart_resolve_path(ty.id, &None, path, PathSource::Expr(None));1283 this.visit_path(path);1284 },1285 );12861287 self.diag_metadata.currently_processing_generic_args = prev;1288 return;1289 }1290 }12911292 self.visit_ty(ty);1293 }1294 GenericArg::Lifetime(lt) => self.visit_lifetime(lt, visit::LifetimeCtxt::GenericArg),1295 GenericArg::Const(ct) => {1296 self.resolve_anon_const(ct, AnonConstKind::ConstArg(IsRepeatExpr::No))1297 }1298 }1299 self.diag_metadata.currently_processing_generic_args = prev;1300 }13011302 fn visit_assoc_item_constraint(&mut self, constraint: &'ast AssocItemConstraint) {1303 self.visit_ident(&constraint.ident);1304 if let Some(ref gen_args) = constraint.gen_args {1305 // Forbid anonymous lifetimes in GAT parameters until proper semantics are decided.1306 self.with_lifetime_rib(LifetimeRibKind::AnonymousReportError, |this| {1307 this.visit_generic_args(gen_args)1308 });1309 }1310 match constraint.kind {1311 AssocItemConstraintKind::Equality { ref term } => match term {1312 Term::Ty(ty) => self.visit_ty(ty),1313 Term::Const(c) => {1314 self.resolve_anon_const(c, AnonConstKind::ConstArg(IsRepeatExpr::No))1315 }1316 },1317 AssocItemConstraintKind::Bound { ref bounds } => {1318 walk_list!(self, visit_param_bound, bounds, BoundKind::Bound);1319 }1320 }1321 }13221323 fn visit_path_segment(&mut self, path_segment: &'ast PathSegment) {1324 let Some(ref args) = path_segment.args else {1325 return;1326 };13271328 match &**args {1329 GenericArgs::AngleBracketed(..) => visit::walk_generic_args(self, args),1330 GenericArgs::Parenthesized(p_args) => {1331 // Probe the lifetime ribs to know how to behave.1332 for rib in self.lifetime_ribs.iter().rev() {1333 match rib.kind {1334 // We are inside a `PolyTraitRef`. The lifetimes are1335 // to be introduced in that (maybe implicit) `for<>` binder.1336 LifetimeRibKind::Generics {1337 binder,1338 kind: LifetimeBinderKind::PolyTrait,1339 ..1340 } => {1341 self.resolve_fn_signature(1342 binder,1343 false,1344 p_args.inputs.iter().map(|ty| (None, &**ty)),1345 &p_args.output,1346 false,1347 );1348 break;1349 }1350 // We have nowhere to introduce generics. Code is malformed,1351 // so use regular lifetime resolution to avoid spurious errors.1352 LifetimeRibKind::Item | LifetimeRibKind::Generics { .. } => {1353 visit::walk_generic_args(self, args);1354 break;1355 }1356 LifetimeRibKind::AnonymousCreateParameter { .. }1357 | LifetimeRibKind::AnonymousReportError1358 | LifetimeRibKind::StaticIfNoLifetimeInScope { .. }1359 | LifetimeRibKind::ImplTrait1360 | LifetimeRibKind::Elided(_)1361 | LifetimeRibKind::ElisionFailure1362 | LifetimeRibKind::ConcreteAnonConst(_)1363 | LifetimeRibKind::ConstParamTy => {}1364 }1365 }1366 }1367 GenericArgs::ParenthesizedElided(_) => {}1368 }1369 }13701371 fn visit_where_predicate(&mut self, p: &'ast WherePredicate) {1372 debug!("visit_where_predicate {:?}", p);1373 let previous_value = replace(&mut self.diag_metadata.current_where_predicate, Some(p));1374 self.with_lifetime_rib(LifetimeRibKind::AnonymousReportError, |this| {1375 if let WherePredicateKind::BoundPredicate(WhereBoundPredicate {1376 bounded_ty,1377 bounds,1378 bound_generic_params,1379 ..1380 }) = &p.kind1381 {1382 let span = p.span.shrink_to_lo().to(bounded_ty.span.shrink_to_lo());1383 this.with_generic_param_rib(1384 bound_generic_params,1385 RibKind::Normal,1386 bounded_ty.id,1387 LifetimeBinderKind::WhereBound,1388 span,1389 |this| {1390 this.visit_generic_params(bound_generic_params, false);1391 this.visit_ty(bounded_ty);1392 for bound in bounds {1393 this.visit_param_bound(bound, BoundKind::Bound)1394 }1395 },1396 );1397 } else {1398 visit::walk_where_predicate(this, p);1399 }1400 });1401 self.diag_metadata.current_where_predicate = previous_value;1402 }14031404 fn visit_inline_asm(&mut self, asm: &'ast InlineAsm) {1405 for (op, _) in &asm.operands {1406 match op {1407 InlineAsmOperand::In { expr, .. }1408 | InlineAsmOperand::Out { expr: Some(expr), .. }1409 | InlineAsmOperand::InOut { expr, .. } => self.visit_expr(expr),1410 InlineAsmOperand::Out { expr: None, .. } => {}1411 InlineAsmOperand::SplitInOut { in_expr, out_expr, .. } => {1412 self.visit_expr(in_expr);1413 if let Some(out_expr) = out_expr {1414 self.visit_expr(out_expr);1415 }1416 }1417 InlineAsmOperand::Const { anon_const, .. } => {1418 // Although this is `DefKind::AnonConst`, it is allowed to reference outer1419 // generic parameters like an inline const.1420 self.resolve_anon_const(anon_const, AnonConstKind::InlineConst);1421 }1422 InlineAsmOperand::Sym { sym } => self.visit_inline_asm_sym(sym),1423 InlineAsmOperand::Label { block } => self.visit_block(block),1424 }1425 }1426 }14271428 fn visit_inline_asm_sym(&mut self, sym: &'ast InlineAsmSym) {1429 // This is similar to the code for AnonConst.1430 self.with_rib(ValueNS, RibKind::InlineAsmSym, |this| {1431 this.with_rib(TypeNS, RibKind::InlineAsmSym, |this| {1432 this.with_label_rib(RibKind::InlineAsmSym, |this| {1433 this.smart_resolve_path(sym.id, &sym.qself, &sym.path, PathSource::Expr(None));1434 visit::walk_inline_asm_sym(this, sym);1435 });1436 })1437 });1438 }14391440 fn visit_variant(&mut self, v: &'ast Variant) {1441 self.resolve_doc_links(&v.attrs, MaybeExported::Ok(v.id));1442 self.visit_id(v.id);1443 walk_list!(self, visit_attribute, &v.attrs);1444 self.visit_vis(&v.vis);1445 self.visit_ident(&v.ident);1446 self.visit_variant_data(&v.data);1447 if let Some(discr) = &v.disr_expr {1448 self.resolve_anon_const(discr, AnonConstKind::EnumDiscriminant);1449 }1450 }14511452 fn visit_field_def(&mut self, f: &'ast FieldDef) {1453 self.resolve_doc_links(&f.attrs, MaybeExported::Ok(f.id));1454 let FieldDef {1455 attrs,1456 id: _,1457 span: _,1458 vis,1459 ident,1460 ty,1461 is_placeholder: _,1462 default,1463 safety: _,1464 } = f;1465 walk_list!(self, visit_attribute, attrs);1466 try_visit!(self.visit_vis(vis));1467 visit_opt!(self, visit_ident, ident);1468 try_visit!(self.visit_ty(ty));1469 if let Some(v) = &default {1470 self.resolve_anon_const(v, AnonConstKind::FieldDefaultValue);1471 }1472 }1473}14741475impl<'a, 'ast, 'ra, 'tcx> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {1476 fn new(resolver: &'a mut Resolver<'ra, 'tcx>) -> LateResolutionVisitor<'a, 'ast, 'ra, 'tcx> {1477 // During late resolution we only track the module component of the parent scope,1478 // although it may be useful to track other components as well for diagnostics.1479 let graph_root = resolver.graph_root;1480 let parent_scope = ParentScope::module(graph_root.to_module(), resolver.arenas);1481 let start_rib_kind = RibKind::Module(graph_root);1482 LateResolutionVisitor {1483 r: resolver,1484 parent_scope,1485 ribs: PerNS {1486 value_ns: vec![Rib::new(start_rib_kind)],1487 type_ns: vec![Rib::new(start_rib_kind)],1488 macro_ns: vec![Rib::new(start_rib_kind)],1489 },1490 last_block_rib: None,1491 label_ribs: Vec::new(),1492 lifetime_ribs: Vec::new(),1493 lifetime_elision_candidates: None,1494 current_trait_ref: None,1495 diag_metadata: Default::default(),1496 // errors at module scope should always be reported1497 in_func_body: false,1498 lifetime_uses: Default::default(),1499 }1500 }15011502 fn maybe_resolve_ident_in_lexical_scope(1503 &mut self,1504 ident: Ident,1505 ns: Namespace,1506 ) -> Option<LateDecl<'ra>> {1507 self.r.resolve_ident_in_lexical_scope(1508 ident,1509 ns,1510 &self.parent_scope,1511 None,1512 &self.ribs[ns],1513 None,1514 Some(&self.diag_metadata),1515 )1516 }15171518 fn resolve_ident_in_lexical_scope(1519 &mut self,1520 ident: Ident,1521 ns: Namespace,1522 finalize: Option<Finalize>,1523 ignore_decl: Option<Decl<'ra>>,1524 ) -> Option<LateDecl<'ra>> {1525 self.r.resolve_ident_in_lexical_scope(1526 ident,1527 ns,1528 &self.parent_scope,1529 finalize,1530 &self.ribs[ns],1531 ignore_decl,1532 Some(&self.diag_metadata),1533 )1534 }15351536 fn resolve_path(1537 &mut self,1538 path: &[Segment],1539 opt_ns: Option<Namespace>, // `None` indicates a module path in import1540 finalize: Option<Finalize>,1541 source: PathSource<'_, 'ast, 'ra>,1542 ) -> PathResult<'ra> {1543 self.r.cm().resolve_path_with_ribs(1544 path,1545 opt_ns,1546 &self.parent_scope,1547 Some(source),1548 finalize.map(|finalize| Finalize { stage: Stage::Late, ..finalize }),1549 Some(&self.ribs),1550 None,1551 None,1552 Some(&self.diag_metadata),1553 )1554 }15551556 // AST resolution1557 //1558 // We maintain a list of value ribs and type ribs.1559 //1560 // Simultaneously, we keep track of the current position in the module1561 // graph in the `parent_scope.module` pointer. When we go to resolve a name in1562 // the value or type namespaces, we first look through all the ribs and1563 // then query the module graph. When we resolve a name in the module1564 // namespace, we can skip all the ribs (since nested modules are not1565 // allowed within blocks in Rust) and jump straight to the current module1566 // graph node.1567 //1568 // Named implementations are handled separately. When we find a method1569 // call, we consult the module node to find all of the implementations in1570 // scope. This information is lazily cached in the module node. We then1571 // generate a fake "implementation scope" containing all the1572 // implementations thus found, for compatibility with old resolve pass.15731574 /// Do some `work` within a new innermost rib of the given `kind` in the given namespace (`ns`).1575 fn with_rib<T>(1576 &mut self,1577 ns: Namespace,1578 kind: RibKind<'ra>,1579 work: impl FnOnce(&mut Self) -> T,1580 ) -> T {1581 self.ribs[ns].push(Rib::new(kind));1582 let ret = work(self);1583 self.ribs[ns].pop();1584 ret1585 }15861587 fn visit_generic_params(&mut self, params: &'ast [GenericParam], add_self_upper: bool) {1588 // For type parameter defaults, we have to ban access1589 // to following type parameters, as the GenericArgs can only1590 // provide previous type parameters as they're built. We1591 // put all the parameters on the ban list and then remove1592 // them one by one as they are processed and become available.1593 let mut forward_ty_ban_rib =1594 Rib::new(RibKind::ForwardGenericParamBan(ForwardGenericParamBanReason::Default));1595 let mut forward_const_ban_rib =1596 Rib::new(RibKind::ForwardGenericParamBan(ForwardGenericParamBanReason::Default));1597 for param in params.iter() {1598 match param.kind {1599 GenericParamKind::Type { .. } => {1600 forward_ty_ban_rib1601 .bindings1602 .insert(Ident::with_dummy_span(param.ident.name), Res::Err);1603 }1604 GenericParamKind::Const { .. } => {1605 forward_const_ban_rib1606 .bindings1607 .insert(Ident::with_dummy_span(param.ident.name), Res::Err);1608 }1609 GenericParamKind::Lifetime => {}1610 }1611 }16121613 // rust-lang/rust#61631: The type `Self` is essentially1614 // another type parameter. For ADTs, we consider it1615 // well-defined only after all of the ADT type parameters have1616 // been provided. Therefore, we do not allow use of `Self`1617 // anywhere in ADT type parameter defaults.1618 //1619 // (We however cannot ban `Self` for defaults on *all* generic1620 // lists; e.g. trait generics can usefully refer to `Self`,1621 // such as in the case of `trait Add<Rhs = Self>`.)1622 if add_self_upper {1623 // (`Some` if + only if we are in ADT's generics.)1624 forward_ty_ban_rib.bindings.insert(Ident::with_dummy_span(kw::SelfUpper), Res::Err);1625 }16261627 // NOTE: We use different ribs here not for a technical reason, but just1628 // for better diagnostics.1629 let mut forward_ty_ban_rib_const_param_ty = Rib {1630 bindings: forward_ty_ban_rib.bindings.clone(),1631 patterns_with_skipped_bindings: Default::default(),1632 kind: RibKind::ForwardGenericParamBan(ForwardGenericParamBanReason::ConstParamTy),1633 };1634 let mut forward_const_ban_rib_const_param_ty = Rib {1635 bindings: forward_const_ban_rib.bindings.clone(),1636 patterns_with_skipped_bindings: Default::default(),1637 kind: RibKind::ForwardGenericParamBan(ForwardGenericParamBanReason::ConstParamTy),1638 };1639 // We'll ban these with a `ConstParamTy` rib, so just clear these ribs for better1640 // diagnostics, so we don't mention anything about const param tys having generics at all.1641 if !self.r.tcx.features().generic_const_parameter_types() {1642 forward_ty_ban_rib_const_param_ty.bindings.clear();1643 forward_const_ban_rib_const_param_ty.bindings.clear();1644 }16451646 self.with_lifetime_rib(LifetimeRibKind::AnonymousReportError, |this| {1647 for param in params {1648 match param.kind {1649 GenericParamKind::Lifetime => {1650 for bound in ¶m.bounds {1651 this.visit_param_bound(bound, BoundKind::Bound);1652 }1653 }1654 GenericParamKind::Type { ref default } => {1655 for bound in ¶m.bounds {1656 this.visit_param_bound(bound, BoundKind::Bound);1657 }16581659 if let Some(ty) = default {1660 this.ribs[TypeNS].push(forward_ty_ban_rib);1661 this.ribs[ValueNS].push(forward_const_ban_rib);1662 this.visit_ty(ty);1663 forward_const_ban_rib = this.ribs[ValueNS].pop().unwrap();1664 forward_ty_ban_rib = this.ribs[TypeNS].pop().unwrap();1665 }16661667 // Allow all following defaults to refer to this type parameter.1668 let i = &Ident::with_dummy_span(param.ident.name);1669 forward_ty_ban_rib.bindings.swap_remove(i);1670 forward_ty_ban_rib_const_param_ty.bindings.swap_remove(i);1671 }1672 GenericParamKind::Const { ref ty, span: _, ref default } => {1673 // Const parameters can't have param bounds.1674 assert!(param.bounds.is_empty());16751676 this.ribs[TypeNS].push(forward_ty_ban_rib_const_param_ty);1677 this.ribs[ValueNS].push(forward_const_ban_rib_const_param_ty);1678 if this.r.tcx.features().generic_const_parameter_types() {1679 this.visit_ty(ty)1680 } else {1681 this.ribs[TypeNS].push(Rib::new(RibKind::ConstParamTy));1682 this.ribs[ValueNS].push(Rib::new(RibKind::ConstParamTy));1683 this.with_lifetime_rib(LifetimeRibKind::ConstParamTy, |this| {1684 this.visit_ty(ty)1685 });1686 this.ribs[TypeNS].pop().unwrap();1687 this.ribs[ValueNS].pop().unwrap();1688 }1689 forward_const_ban_rib_const_param_ty = this.ribs[ValueNS].pop().unwrap();1690 forward_ty_ban_rib_const_param_ty = this.ribs[TypeNS].pop().unwrap();16911692 if let Some(expr) = default {1693 this.ribs[TypeNS].push(forward_ty_ban_rib);1694 this.ribs[ValueNS].push(forward_const_ban_rib);1695 this.resolve_anon_const(1696 expr,1697 AnonConstKind::ConstArg(IsRepeatExpr::No),1698 );1699 forward_const_ban_rib = this.ribs[ValueNS].pop().unwrap();1700 forward_ty_ban_rib = this.ribs[TypeNS].pop().unwrap();1701 }17021703 // Allow all following defaults to refer to this const parameter.1704 let i = &Ident::with_dummy_span(param.ident.name);1705 forward_const_ban_rib.bindings.swap_remove(i);1706 forward_const_ban_rib_const_param_ty.bindings.swap_remove(i);1707 }1708 }1709 }1710 })1711 }17121713 #[instrument(level = "debug", skip(self, work))]1714 fn with_lifetime_rib<T>(1715 &mut self,1716 kind: LifetimeRibKind,1717 work: impl FnOnce(&mut Self) -> T,1718 ) -> T {1719 self.lifetime_ribs.push(LifetimeRib::new(kind));1720 let outer_elision_candidates = self.lifetime_elision_candidates.take();1721 let ret = work(self);1722 self.lifetime_elision_candidates = outer_elision_candidates;1723 self.lifetime_ribs.pop();1724 ret1725 }17261727 #[instrument(level = "debug", skip(self))]1728 fn resolve_lifetime(&mut self, lifetime: &'ast Lifetime, use_ctxt: visit::LifetimeCtxt) {1729 let ident = lifetime.ident;17301731 if ident.name == kw::StaticLifetime {1732 self.record_lifetime_res(1733 lifetime.id,1734 LifetimeRes::Static,1735 LifetimeElisionCandidate::Named,1736 );1737 return;1738 }17391740 if ident.name == kw::UnderscoreLifetime {1741 return self.resolve_anonymous_lifetime(lifetime, lifetime.id, false);1742 }17431744 let mut lifetime_rib_iter = self.lifetime_ribs.iter().rev();1745 while let Some(rib) = lifetime_rib_iter.next() {1746 let normalized_ident = ident.normalize_to_macros_2_0();1747 if let Some(&(_, res)) = rib.bindings.get(&normalized_ident) {1748 self.record_lifetime_res(lifetime.id, res, LifetimeElisionCandidate::Named);17491750 if let LifetimeRes::Param { param, binder } = res {1751 match self.lifetime_uses.entry(param) {1752 Entry::Vacant(v) => {1753 debug!("First use of {:?} at {:?}", res, ident.span);1754 let use_set = self1755 .lifetime_ribs1756 .iter()1757 .rev()1758 .find_map(|rib| match rib.kind {1759 // Do not suggest eliding a lifetime where an anonymous1760 // lifetime would be illegal.1761 LifetimeRibKind::Item1762 | LifetimeRibKind::AnonymousReportError1763 | LifetimeRibKind::StaticIfNoLifetimeInScope { .. }1764 | LifetimeRibKind::ElisionFailure => Some(LifetimeUseSet::Many),1765 // An anonymous lifetime is legal here, and bound to the right1766 // place, go ahead.1767 LifetimeRibKind::AnonymousCreateParameter {1768 binder: anon_binder,1769 ..1770 } => Some(if binder == anon_binder {1771 LifetimeUseSet::One { use_span: ident.span, use_ctxt }1772 } else {1773 LifetimeUseSet::Many1774 }),1775 // Only report if eliding the lifetime would have the same1776 // semantics.1777 LifetimeRibKind::Elided(r) => Some(if res == r {1778 LifetimeUseSet::One { use_span: ident.span, use_ctxt }1779 } else {1780 LifetimeUseSet::Many1781 }),1782 LifetimeRibKind::Generics { .. }1783 | LifetimeRibKind::ConstParamTy => None,1784 LifetimeRibKind::ConcreteAnonConst(_) => {1785 span_bug!(ident.span, "unexpected rib kind: {:?}", rib.kind)1786 }17871788 LifetimeRibKind::ImplTrait => {1789 if self.r.tcx.features().anonymous_lifetime_in_impl_trait()1790 {1791 None1792 } else {1793 Some(LifetimeUseSet::Many)1794 }1795 }1796 })1797 .unwrap_or(LifetimeUseSet::Many);1798 debug!(?use_ctxt, ?use_set);1799 v.insert(use_set);1800 }1801 Entry::Occupied(mut o) => {1802 debug!("Many uses of {:?} at {:?}", res, ident.span);1803 *o.get_mut() = LifetimeUseSet::Many;1804 }1805 }1806 }1807 return;1808 }18091810 match rib.kind {1811 LifetimeRibKind::Item => break,1812 LifetimeRibKind::ConstParamTy => {1813 let guar = self.emit_non_static_lt_in_const_param_ty_error(lifetime);1814 self.record_lifetime_res(1815 lifetime.id,1816 LifetimeRes::Error(guar),1817 LifetimeElisionCandidate::Ignore,1818 );1819 return;1820 }1821 LifetimeRibKind::ConcreteAnonConst(cause) => {1822 let guar = self.emit_forbidden_non_static_lifetime_error(cause, lifetime);1823 self.record_lifetime_res(1824 lifetime.id,1825 LifetimeRes::Error(guar),1826 LifetimeElisionCandidate::Ignore,1827 );1828 return;1829 }1830 LifetimeRibKind::AnonymousCreateParameter { .. }1831 | LifetimeRibKind::Elided(_)1832 | LifetimeRibKind::Generics { .. }1833 | LifetimeRibKind::ElisionFailure1834 | LifetimeRibKind::AnonymousReportError1835 | LifetimeRibKind::ImplTrait1836 | LifetimeRibKind::StaticIfNoLifetimeInScope { .. } => {}1837 }1838 }18391840 let normalized_ident = ident.normalize_to_macros_2_0();1841 let outer_res = lifetime_rib_iter1842 .find_map(|rib| rib.bindings.get_key_value(&normalized_ident).map(|(&outer, _)| outer));18431844 let guar = self.emit_undeclared_lifetime_error(lifetime, outer_res);1845 self.record_lifetime_res(1846 lifetime.id,1847 LifetimeRes::Error(guar),1848 LifetimeElisionCandidate::Named,1849 );1850 }18511852 #[instrument(level = "debug", skip(self))]1853 fn resolve_anonymous_lifetime(1854 &mut self,1855 lifetime: &Lifetime,1856 id_for_lint: NodeId,1857 elided: bool,1858 ) {1859 debug_assert_eq!(lifetime.ident.name, kw::UnderscoreLifetime);18601861 let kind =1862 if elided { MissingLifetimeKind::Ampersand } else { MissingLifetimeKind::Underscore };1863 let missing_lifetime = MissingLifetime {1864 id: lifetime.id,1865 span: lifetime.ident.span,1866 kind,1867 count: 1,1868 id_for_lint,1869 };1870 let elision_candidate = LifetimeElisionCandidate::Missing(missing_lifetime);1871 for (i, rib) in self.lifetime_ribs.iter().enumerate().rev() {1872 debug!(?rib.kind);1873 match rib.kind {1874 LifetimeRibKind::AnonymousCreateParameter { binder, .. } => {1875 let res = self.create_fresh_lifetime(lifetime.ident, binder, kind);1876 self.record_lifetime_res(lifetime.id, res, elision_candidate);1877 return;1878 }1879 LifetimeRibKind::StaticIfNoLifetimeInScope { lint_id: node_id, emit_lint } => {1880 let mut lifetimes_in_scope = vec![];1881 for rib in self.lifetime_ribs[..i].iter().rev() {1882 lifetimes_in_scope.extend(rib.bindings.iter().map(|(ident, _)| ident.span));1883 // Consider any anonymous lifetimes, too1884 if let LifetimeRibKind::AnonymousCreateParameter { binder, .. } = rib.kind1885 && let Some(extra) = self.r.extra_lifetime_params_map.get(&binder)1886 {1887 lifetimes_in_scope.extend(extra.iter().map(|(ident, _, _)| ident.span));1888 }1889 if let LifetimeRibKind::Item = rib.kind {1890 break;1891 }1892 }1893 if lifetimes_in_scope.is_empty() {1894 self.record_lifetime_res(1895 lifetime.id,1896 LifetimeRes::Static,1897 elision_candidate,1898 );1899 return;1900 } else if emit_lint {1901 let lt_span = if elided {1902 lifetime.ident.span.shrink_to_hi()1903 } else {1904 lifetime.ident.span1905 };1906 let code = if elided { "'static " } else { "'static" };19071908 self.r.lint_buffer.buffer_lint(1909 lint::builtin::ELIDED_LIFETIMES_IN_ASSOCIATED_CONSTANT,1910 node_id,1911 lifetime.ident.span,1912 crate::errors::AssociatedConstElidedLifetime {1913 elided,1914 code,1915 span: lt_span,1916 lifetimes_in_scope: lifetimes_in_scope.into(),1917 },1918 );1919 }1920 }1921 LifetimeRibKind::AnonymousReportError => {1922 let guar = if elided {1923 let suggestion = self.lifetime_ribs[i..].iter().rev().find_map(|rib| {1924 if let LifetimeRibKind::Generics {1925 span,1926 kind: LifetimeBinderKind::PolyTrait | LifetimeBinderKind::WhereBound,1927 ..1928 } = rib.kind1929 {1930 Some(errors::ElidedAnonymousLifetimeReportErrorSuggestion {1931 lo: span.shrink_to_lo(),1932 hi: lifetime.ident.span.shrink_to_hi(),1933 })1934 } else {1935 None1936 }1937 });1938 // are we trying to use an anonymous lifetime1939 // on a non GAT associated trait type?1940 if !self.in_func_body1941 && let Some((module, _)) = &self.current_trait_ref1942 && let Some(ty) = &self.diag_metadata.current_self_type1943 && Some(true) == self.diag_metadata.in_non_gat_assoc_type1944 && let crate::ModuleKind::Def(DefKind::Trait, trait_id, _, _) =1945 module.kind1946 {1947 if def_id_matches_path(1948 self.r.tcx,1949 trait_id,1950 &["core", "iter", "traits", "iterator", "Iterator"],1951 ) {1952 self.r.dcx().emit_err(errors::LendingIteratorReportError {1953 lifetime: lifetime.ident.span,1954 ty: ty.span,1955 })1956 } else {1957 let decl = if !trait_id.is_local()1958 && let Some(assoc) = self.diag_metadata.current_impl_item1959 && let AssocItemKind::Type(_) = assoc.kind1960 && let assocs = self.r.tcx.associated_items(trait_id)1961 && let Some(ident) = assoc.kind.ident()1962 && let Some(assoc) = assocs.find_by_ident_and_kind(1963 self.r.tcx,1964 ident,1965 AssocTag::Type,1966 trait_id,1967 ) {1968 let mut decl: MultiSpan =1969 self.r.tcx.def_span(assoc.def_id).into();1970 decl.push_span_label(1971 self.r.tcx.def_span(trait_id),1972 String::new(),1973 );1974 decl1975 } else {1976 DUMMY_SP.into()1977 };1978 let mut err = self.r.dcx().create_err(1979 errors::AnonymousLifetimeNonGatReportError {1980 lifetime: lifetime.ident.span,1981 decl,1982 },1983 );1984 self.point_at_impl_lifetimes(&mut err, i, lifetime.ident.span);1985 err.emit()1986 }1987 } else {1988 self.r.dcx().emit_err(errors::ElidedAnonymousLifetimeReportError {1989 span: lifetime.ident.span,1990 suggestion,1991 })1992 }1993 } else {1994 self.r.dcx().emit_err(errors::ExplicitAnonymousLifetimeReportError {1995 span: lifetime.ident.span,1996 })1997 };1998 self.record_lifetime_res(1999 lifetime.id,2000 LifetimeRes::Error(guar),
Findings
✓ No findings reported for this file.