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rustc_resolve/
ident.rs

1use std::ops::ControlFlow;
2
3use Determinacy::*;
4use Namespace::*;
5use rustc_ast::{self as ast, NodeId};
6use rustc_errors::ErrorGuaranteed;
7use rustc_hir::def::{DefKind, MacroKinds, Namespace, NonMacroAttrKind, PartialRes, PerNS};
8use rustc_middle::{bug, span_bug};
9use rustc_session::errors::feature_err;
10use rustc_session::lint::builtin::PROC_MACRO_DERIVE_RESOLUTION_FALLBACK;
11use rustc_span::edition::Edition;
12use rustc_span::hygiene::{ExpnId, ExpnKind, LocalExpnId, MacroKind, SyntaxContext};
13use rustc_span::{Ident, Span, kw, sym};
14use smallvec::SmallVec;
15use tracing::{debug, instrument};
16
17use crate::errors::{ParamKindInEnumDiscriminant, ParamKindInNonTrivialAnonConst};
18use crate::hygiene::Macros20NormalizedSyntaxContext;
19use crate::imports::{Import, NameResolution};
20use crate::late::{
21    ConstantHasGenerics, DiagMetadata, NoConstantGenericsReason, PathSource, Rib, RibKind,
22};
23use crate::macros::{MacroRulesScope, sub_namespace_match};
24use crate::{
25    AmbiguityError, AmbiguityKind, AmbiguityWarning, BindingKey, CmResolver, Decl, DeclKind,
26    Determinacy, Finalize, IdentKey, ImportKind, ImportSummary, LateDecl, LocalModule, Module,
27    ModuleKind, ModuleOrUniformRoot, ParentScope, PathResult, PrivacyError, Res, ResolutionError,
28    Resolver, Scope, ScopeSet, Segment, Stage, Symbol, Used, errors,
29};
30
31#[derive(#[automatically_derived]
impl ::core::marker::Copy for UsePrelude { }Copy, #[automatically_derived]
impl ::core::clone::Clone for UsePrelude {
    #[inline]
    fn clone(&self) -> UsePrelude { *self }
}Clone)]
32pub enum UsePrelude {
33    No,
34    Yes,
35}
36
37impl From<UsePrelude> for bool {
38    fn from(up: UsePrelude) -> bool {
39        #[allow(non_exhaustive_omitted_patterns)] match up {
    UsePrelude::Yes => true,
    _ => false,
}matches!(up, UsePrelude::Yes)
40    }
41}
42
43#[derive(#[automatically_derived]
impl ::core::fmt::Debug for Shadowing {
    #[inline]
    fn fmt(&self, f: &mut ::core::fmt::Formatter) -> ::core::fmt::Result {
        ::core::fmt::Formatter::write_str(f,
            match self {
                Shadowing::Restricted => "Restricted",
                Shadowing::Unrestricted => "Unrestricted",
            })
    }
}Debug, #[automatically_derived]
impl ::core::cmp::PartialEq for Shadowing {
    #[inline]
    fn eq(&self, other: &Shadowing) -> bool {
        let __self_discr = ::core::intrinsics::discriminant_value(self);
        let __arg1_discr = ::core::intrinsics::discriminant_value(other);
        __self_discr == __arg1_discr
    }
}PartialEq, #[automatically_derived]
impl ::core::clone::Clone for Shadowing {
    #[inline]
    fn clone(&self) -> Shadowing { *self }
}Clone, #[automatically_derived]
impl ::core::marker::Copy for Shadowing { }Copy)]
44enum Shadowing {
45    Restricted,
46    Unrestricted,
47}
48
49impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
50    /// A generic scope visitor.
51    /// Visits scopes in order to resolve some identifier in them or perform other actions.
52    /// If the callback returns `Some` result, we stop visiting scopes and return it.
53    pub(crate) fn visit_scopes<'r, T>(
54        mut self: CmResolver<'r, 'ra, 'tcx>,
55        scope_set: ScopeSet<'ra>,
56        parent_scope: &ParentScope<'ra>,
57        mut ctxt: Macros20NormalizedSyntaxContext,
58        orig_ident_span: Span,
59        derive_fallback_lint_id: Option<NodeId>,
60        mut visitor: impl FnMut(
61            CmResolver<'_, 'ra, 'tcx>,
62            Scope<'ra>,
63            UsePrelude,
64            Macros20NormalizedSyntaxContext,
65        ) -> ControlFlow<T>,
66    ) -> Option<T> {
67        // General principles:
68        // 1. Not controlled (user-defined) names should have higher priority than controlled names
69        //    built into the language or standard library. This way we can add new names into the
70        //    language or standard library without breaking user code.
71        // 2. "Closed set" below means new names cannot appear after the current resolution attempt.
72        // Places to search (in order of decreasing priority):
73        // (Type NS)
74        // 1. FIXME: Ribs (type parameters), there's no necessary infrastructure yet
75        //    (open set, not controlled).
76        // 2. Names in modules (both normal `mod`ules and blocks), loop through hygienic parents
77        //    (open, not controlled).
78        // 3. Extern prelude (open, the open part is from macro expansions, not controlled).
79        // 4. Tool modules (closed, controlled right now, but not in the future).
80        // 5. Standard library prelude (de-facto closed, controlled).
81        // 6. Language prelude (closed, controlled).
82        // (Value NS)
83        // 1. FIXME: Ribs (local variables), there's no necessary infrastructure yet
84        //    (open set, not controlled).
85        // 2. Names in modules (both normal `mod`ules and blocks), loop through hygienic parents
86        //    (open, not controlled).
87        // 3. Standard library prelude (de-facto closed, controlled).
88        // (Macro NS)
89        // 1-3. Derive helpers (open, not controlled). All ambiguities with other names
90        //    are currently reported as errors. They should be higher in priority than preludes
91        //    and probably even names in modules according to the "general principles" above. They
92        //    also should be subject to restricted shadowing because are effectively produced by
93        //    derives (you need to resolve the derive first to add helpers into scope), but they
94        //    should be available before the derive is expanded for compatibility.
95        //    It's mess in general, so we are being conservative for now.
96        // 1-3. `macro_rules` (open, not controlled), loop through `macro_rules` scopes. Have higher
97        //    priority than prelude macros, but create ambiguities with macros in modules.
98        // 1-3. Names in modules (both normal `mod`ules and blocks), loop through hygienic parents
99        //    (open, not controlled). Have higher priority than prelude macros, but create
100        //    ambiguities with `macro_rules`.
101        // 4. `macro_use` prelude (open, the open part is from macro expansions, not controlled).
102        // 4a. User-defined prelude from macro-use
103        //    (open, the open part is from macro expansions, not controlled).
104        // 4b. "Standard library prelude" part implemented through `macro-use` (closed, controlled).
105        // 4c. Standard library prelude (de-facto closed, controlled).
106        // 6. Language prelude: builtin attributes (closed, controlled).
107
108        let (ns, macro_kind) = match scope_set {
109            ScopeSet::All(ns)
110            | ScopeSet::Module(ns, _)
111            | ScopeSet::ModuleAndExternPrelude(ns, _) => (ns, None),
112            ScopeSet::ExternPrelude => (TypeNS, None),
113            ScopeSet::Macro(macro_kind) => (MacroNS, Some(macro_kind)),
114        };
115        let module = match scope_set {
116            // Start with the specified module.
117            ScopeSet::Module(_, module) | ScopeSet::ModuleAndExternPrelude(_, module) => module,
118            // Jump out of trait or enum modules, they do not act as scopes.
119            _ => parent_scope.module.nearest_item_scope(),
120        };
121        let module_only = #[allow(non_exhaustive_omitted_patterns)] match scope_set {
    ScopeSet::Module(..) => true,
    _ => false,
}matches!(scope_set, ScopeSet::Module(..));
122        let module_and_extern_prelude = #[allow(non_exhaustive_omitted_patterns)] match scope_set {
    ScopeSet::ModuleAndExternPrelude(..) => true,
    _ => false,
}matches!(scope_set, ScopeSet::ModuleAndExternPrelude(..));
123        let extern_prelude = #[allow(non_exhaustive_omitted_patterns)] match scope_set {
    ScopeSet::ExternPrelude => true,
    _ => false,
}matches!(scope_set, ScopeSet::ExternPrelude);
124        let mut scope = match ns {
125            _ if module_only || module_and_extern_prelude => Scope::ModuleNonGlobs(module, None),
126            _ if extern_prelude => Scope::ExternPreludeItems,
127            TypeNS | ValueNS => Scope::ModuleNonGlobs(module, None),
128            MacroNS => Scope::DeriveHelpers(parent_scope.expansion),
129        };
130        let mut use_prelude = !module.no_implicit_prelude;
131
132        loop {
133            let visit = match scope {
134                // Derive helpers are not in scope when resolving derives in the same container.
135                Scope::DeriveHelpers(expn_id) => {
136                    !(expn_id == parent_scope.expansion && macro_kind == Some(MacroKind::Derive))
137                }
138                Scope::DeriveHelpersCompat => true,
139                Scope::MacroRules(macro_rules_scope) => {
140                    // Use "path compression" on `macro_rules` scope chains. This is an optimization
141                    // used to avoid long scope chains, see the comments on `MacroRulesScopeRef`.
142                    // As another consequence of this optimization visitors never observe invocation
143                    // scopes for macros that were already expanded.
144                    while let MacroRulesScope::Invocation(invoc_id) = macro_rules_scope.get() {
145                        if let Some(next_scope) = self.output_macro_rules_scopes.get(&invoc_id) {
146                            macro_rules_scope.set(next_scope.get());
147                        } else {
148                            break;
149                        }
150                    }
151                    true
152                }
153                Scope::ModuleNonGlobs(..) | Scope::ModuleGlobs(..) => true,
154                Scope::MacroUsePrelude => use_prelude || orig_ident_span.is_rust_2015(),
155                Scope::BuiltinAttrs => true,
156                Scope::ExternPreludeItems | Scope::ExternPreludeFlags => {
157                    use_prelude || module_and_extern_prelude || extern_prelude
158                }
159                Scope::ToolPrelude => use_prelude,
160                Scope::StdLibPrelude => use_prelude || ns == MacroNS,
161                Scope::BuiltinTypes => true,
162            };
163
164            if visit {
165                let use_prelude = if use_prelude { UsePrelude::Yes } else { UsePrelude::No };
166                if let ControlFlow::Break(break_result) =
167                    visitor(self.reborrow(), scope, use_prelude, ctxt)
168                {
169                    return Some(break_result);
170                }
171            }
172
173            scope = match scope {
174                Scope::DeriveHelpers(LocalExpnId::ROOT) => Scope::DeriveHelpersCompat,
175                Scope::DeriveHelpers(expn_id) => {
176                    // Derive helpers are not visible to code generated by bang or derive macros.
177                    let expn_data = expn_id.expn_data();
178                    match expn_data.kind {
179                        ExpnKind::Root
180                        | ExpnKind::Macro(MacroKind::Bang | MacroKind::Derive, _) => {
181                            Scope::DeriveHelpersCompat
182                        }
183                        _ => Scope::DeriveHelpers(expn_data.parent.expect_local()),
184                    }
185                }
186                Scope::DeriveHelpersCompat => Scope::MacroRules(parent_scope.macro_rules),
187                Scope::MacroRules(macro_rules_scope) => match macro_rules_scope.get() {
188                    MacroRulesScope::Def(binding) => {
189                        Scope::MacroRules(binding.parent_macro_rules_scope)
190                    }
191                    MacroRulesScope::Invocation(invoc_id) => {
192                        Scope::MacroRules(self.invocation_parent_scopes[&invoc_id].macro_rules)
193                    }
194                    MacroRulesScope::Empty => Scope::ModuleNonGlobs(module, None),
195                },
196                Scope::ModuleNonGlobs(module, lint_id) => Scope::ModuleGlobs(module, lint_id),
197                Scope::ModuleGlobs(..) if module_only => break,
198                Scope::ModuleGlobs(..) if module_and_extern_prelude => match ns {
199                    TypeNS => {
200                        ctxt.update_unchecked(|ctxt| ctxt.adjust(ExpnId::root()));
201                        Scope::ExternPreludeItems
202                    }
203                    ValueNS | MacroNS => break,
204                },
205                Scope::ModuleGlobs(module, prev_lint_id) => {
206                    use_prelude = !module.no_implicit_prelude;
207                    match self.hygienic_lexical_parent(module, &mut ctxt, derive_fallback_lint_id) {
208                        Some((parent_module, lint_id)) => {
209                            Scope::ModuleNonGlobs(parent_module, lint_id.or(prev_lint_id))
210                        }
211                        None => {
212                            ctxt.update_unchecked(|ctxt| ctxt.adjust(ExpnId::root()));
213                            match ns {
214                                TypeNS => Scope::ExternPreludeItems,
215                                ValueNS => Scope::StdLibPrelude,
216                                MacroNS => Scope::MacroUsePrelude,
217                            }
218                        }
219                    }
220                }
221                Scope::MacroUsePrelude => Scope::StdLibPrelude,
222                Scope::BuiltinAttrs => break, // nowhere else to search
223                Scope::ExternPreludeItems => Scope::ExternPreludeFlags,
224                Scope::ExternPreludeFlags if module_and_extern_prelude || extern_prelude => break,
225                Scope::ExternPreludeFlags => Scope::ToolPrelude,
226                Scope::ToolPrelude => Scope::StdLibPrelude,
227                Scope::StdLibPrelude => match ns {
228                    TypeNS => Scope::BuiltinTypes,
229                    ValueNS => break, // nowhere else to search
230                    MacroNS => Scope::BuiltinAttrs,
231                },
232                Scope::BuiltinTypes => break, // nowhere else to search
233            };
234        }
235
236        None
237    }
238
239    fn hygienic_lexical_parent(
240        &self,
241        module: Module<'ra>,
242        ctxt: &mut Macros20NormalizedSyntaxContext,
243        derive_fallback_lint_id: Option<NodeId>,
244    ) -> Option<(Module<'ra>, Option<NodeId>)> {
245        if !module.expansion.outer_expn_is_descendant_of(**ctxt) {
246            let expn_id = ctxt.update_unchecked(|ctxt| ctxt.remove_mark());
247            return Some((self.expn_def_scope(expn_id), None));
248        }
249
250        if let ModuleKind::Block = module.kind {
251            return Some((module.parent.unwrap().nearest_item_scope(), None));
252        }
253
254        // We need to support the next case under a deprecation warning
255        // ```
256        // struct MyStruct;
257        // ---- begin: this comes from a proc macro derive
258        // mod implementation_details {
259        //     // Note that `MyStruct` is not in scope here.
260        //     impl SomeTrait for MyStruct { ... }
261        // }
262        // ---- end
263        // ```
264        // So we have to fall back to the module's parent during lexical resolution in this case.
265        if derive_fallback_lint_id.is_some()
266            && let Some(parent) = module.parent
267            // Inner module is inside the macro
268            && module.expansion != parent.expansion
269            // Parent module is outside of the macro
270            && module.expansion.is_descendant_of(parent.expansion)
271            // The macro is a proc macro derive
272            && let Some(def_id) = module.expansion.expn_data().macro_def_id
273        {
274            let ext = self.get_macro_by_def_id(def_id);
275            if ext.builtin_name.is_none()
276                && ext.macro_kinds() == MacroKinds::DERIVE
277                && parent.expansion.outer_expn_is_descendant_of(**ctxt)
278            {
279                return Some((parent, derive_fallback_lint_id));
280            }
281        }
282
283        None
284    }
285
286    /// This resolves the identifier `ident` in the namespace `ns` in the current lexical scope.
287    /// More specifically, we proceed up the hierarchy of scopes and return the binding for
288    /// `ident` in the first scope that defines it (or None if no scopes define it).
289    ///
290    /// A block's items are above its local variables in the scope hierarchy, regardless of where
291    /// the items are defined in the block. For example,
292    /// ```rust
293    /// fn f() {
294    ///    g(); // Since there are no local variables in scope yet, this resolves to the item.
295    ///    let g = || {};
296    ///    fn g() {}
297    ///    g(); // This resolves to the local variable `g` since it shadows the item.
298    /// }
299    /// ```
300    ///
301    /// Invariant: This must only be called during main resolution, not during
302    /// import resolution.
303    #[allow(clippy :: suspicious_else_formatting)]
{
    let __tracing_attr_span;
    let __tracing_attr_guard;
    if ::tracing::Level::DEBUG <= ::tracing::level_filters::STATIC_MAX_LEVEL
                &&
                ::tracing::Level::DEBUG <=
                    ::tracing::level_filters::LevelFilter::current() ||
            { false } {
        __tracing_attr_span =
            {
                use ::tracing::__macro_support::Callsite as _;
                static __CALLSITE: ::tracing::callsite::DefaultCallsite =
                    {
                        static META: ::tracing::Metadata<'static> =
                            {
                                ::tracing_core::metadata::Metadata::new("resolve_ident_in_lexical_scope",
                                    "rustc_resolve::ident", ::tracing::Level::DEBUG,
                                    ::tracing_core::__macro_support::Option::Some("compiler/rustc_resolve/src/ident.rs"),
                                    ::tracing_core::__macro_support::Option::Some(303u32),
                                    ::tracing_core::__macro_support::Option::Some("rustc_resolve::ident"),
                                    ::tracing_core::field::FieldSet::new(&["ident", "ns",
                                                    "parent_scope", "finalize", "ignore_decl", "diag_metadata"],
                                        ::tracing_core::callsite::Identifier(&__CALLSITE)),
                                    ::tracing::metadata::Kind::SPAN)
                            };
                        ::tracing::callsite::DefaultCallsite::new(&META)
                    };
                let mut interest = ::tracing::subscriber::Interest::never();
                if ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::STATIC_MAX_LEVEL &&
                                ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::LevelFilter::current() &&
                            { interest = __CALLSITE.interest(); !interest.is_never() }
                        &&
                        ::tracing::__macro_support::__is_enabled(__CALLSITE.metadata(),
                            interest) {
                    let meta = __CALLSITE.metadata();
                    ::tracing::Span::new(meta,
                        &{
                                #[allow(unused_imports)]
                                use ::tracing::field::{debug, display, Value};
                                let mut iter = meta.fields().iter();
                                meta.fields().value_set(&[(&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ident)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ns)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&parent_scope)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&finalize)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ignore_decl)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&diag_metadata)
                                                            as &dyn Value))])
                            })
                } else {
                    let span =
                        ::tracing::__macro_support::__disabled_span(__CALLSITE.metadata());
                    {};
                    span
                }
            };
        __tracing_attr_guard = __tracing_attr_span.enter();
    }

    #[warn(clippy :: suspicious_else_formatting)]
    {

        #[allow(unknown_lints, unreachable_code, clippy ::
        diverging_sub_expression, clippy :: empty_loop, clippy ::
        let_unit_value, clippy :: let_with_type_underscore, clippy ::
        needless_return, clippy :: unreachable)]
        if false {
            let __tracing_attr_fake_return: Option<LateDecl<'ra>> = loop {};
            return __tracing_attr_fake_return;
        }
        {
            let orig_ident = ident;
            let (general_span, normalized_span) =
                if ident.name == kw::SelfUpper {
                    let empty_span =
                        ident.span.with_ctxt(SyntaxContext::root());
                    (empty_span, empty_span)
                } else if ns == TypeNS {
                    let normalized_span = ident.span.normalize_to_macros_2_0();
                    (normalized_span, normalized_span)
                } else {
                    (ident.span.normalize_to_macro_rules(),
                        ident.span.normalize_to_macros_2_0())
                };
            ident.span = general_span;
            let normalized_ident = Ident { span: normalized_span, ..ident };
            for (i, rib) in ribs.iter().enumerate().rev() {
                {
                    use ::tracing::__macro_support::Callsite as _;
                    static __CALLSITE: ::tracing::callsite::DefaultCallsite =
                        {
                            static META: ::tracing::Metadata<'static> =
                                {
                                    ::tracing_core::metadata::Metadata::new("event compiler/rustc_resolve/src/ident.rs:330",
                                        "rustc_resolve::ident", ::tracing::Level::DEBUG,
                                        ::tracing_core::__macro_support::Option::Some("compiler/rustc_resolve/src/ident.rs"),
                                        ::tracing_core::__macro_support::Option::Some(330u32),
                                        ::tracing_core::__macro_support::Option::Some("rustc_resolve::ident"),
                                        ::tracing_core::field::FieldSet::new(&["message"],
                                            ::tracing_core::callsite::Identifier(&__CALLSITE)),
                                        ::tracing::metadata::Kind::EVENT)
                                };
                            ::tracing::callsite::DefaultCallsite::new(&META)
                        };
                    let enabled =
                        ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::STATIC_MAX_LEVEL &&
                                ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::LevelFilter::current() &&
                            {
                                let interest = __CALLSITE.interest();
                                !interest.is_never() &&
                                    ::tracing::__macro_support::__is_enabled(__CALLSITE.metadata(),
                                        interest)
                            };
                    if enabled {
                        (|value_set: ::tracing::field::ValueSet|
                                    {
                                        let meta = __CALLSITE.metadata();
                                        ::tracing::Event::dispatch(meta, &value_set);
                                        ;
                                    })({
                                #[allow(unused_imports)]
                                use ::tracing::field::{debug, display, Value};
                                let mut iter = __CALLSITE.metadata().fields().iter();
                                __CALLSITE.metadata().fields().value_set(&[(&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&format_args!("walk rib\n{0:?}",
                                                                    rib.bindings) as &dyn Value))])
                            });
                    } else { ; }
                };
                let rib_ident =
                    if rib.kind.contains_params() {
                        normalized_ident
                    } else { ident };
                if let Some((original_rib_ident_def, res)) =
                        rib.bindings.get_key_value(&rib_ident) {
                    return Some(LateDecl::RibDef(self.validate_res_from_ribs(i,
                                    rib_ident, *res, finalize.map(|_| general_span),
                                    *original_rib_ident_def, ribs, diag_metadata)));
                } else if let RibKind::Block(Some(module)) = rib.kind &&
                        let Ok(binding) =
                            self.cm().resolve_ident_in_scope_set(ident,
                                ScopeSet::Module(ns, module.to_module()), parent_scope,
                                finalize.map(|finalize|
                                        Finalize { used: Used::Scope, ..finalize }), ignore_decl,
                                None) {
                    return Some(LateDecl::Decl(binding));
                } else if let RibKind::Module(module) = rib.kind {
                    let parent_scope =
                        &ParentScope {
                                module: module.to_module(),
                                ..*parent_scope
                            };
                    let finalize =
                        finalize.map(|f| Finalize { stage: Stage::Late, ..f });
                    return self.cm().resolve_ident_in_scope_set(orig_ident,
                                    ScopeSet::All(ns), parent_scope, finalize, ignore_decl,
                                    None).ok().map(LateDecl::Decl);
                }
                if let RibKind::MacroDefinition(def) = rib.kind &&
                        def == self.macro_def(ident.span.ctxt()) {
                    ident.span.remove_mark();
                }
            }
            ::core::panicking::panic("internal error: entered unreachable code")
        }
    }
}#[instrument(level = "debug", skip(self, ribs))]
304    pub(crate) fn resolve_ident_in_lexical_scope(
305        &mut self,
306        mut ident: Ident,
307        ns: Namespace,
308        parent_scope: &ParentScope<'ra>,
309        finalize: Option<Finalize>,
310        ribs: &[Rib<'ra>],
311        ignore_decl: Option<Decl<'ra>>,
312        diag_metadata: Option<&DiagMetadata<'_>>,
313    ) -> Option<LateDecl<'ra>> {
314        let orig_ident = ident;
315        let (general_span, normalized_span) = if ident.name == kw::SelfUpper {
316            // FIXME(jseyfried) improve `Self` hygiene
317            let empty_span = ident.span.with_ctxt(SyntaxContext::root());
318            (empty_span, empty_span)
319        } else if ns == TypeNS {
320            let normalized_span = ident.span.normalize_to_macros_2_0();
321            (normalized_span, normalized_span)
322        } else {
323            (ident.span.normalize_to_macro_rules(), ident.span.normalize_to_macros_2_0())
324        };
325        ident.span = general_span;
326        let normalized_ident = Ident { span: normalized_span, ..ident };
327
328        // Walk backwards up the ribs in scope.
329        for (i, rib) in ribs.iter().enumerate().rev() {
330            debug!("walk rib\n{:?}", rib.bindings);
331            // Use the rib kind to determine whether we are resolving parameters
332            // (macro 2.0 hygiene) or local variables (`macro_rules` hygiene).
333            let rib_ident = if rib.kind.contains_params() { normalized_ident } else { ident };
334            if let Some((original_rib_ident_def, res)) = rib.bindings.get_key_value(&rib_ident) {
335                // The ident resolves to a type parameter or local variable.
336                return Some(LateDecl::RibDef(self.validate_res_from_ribs(
337                    i,
338                    rib_ident,
339                    *res,
340                    finalize.map(|_| general_span),
341                    *original_rib_ident_def,
342                    ribs,
343                    diag_metadata,
344                )));
345            } else if let RibKind::Block(Some(module)) = rib.kind
346                && let Ok(binding) = self.cm().resolve_ident_in_scope_set(
347                    ident,
348                    ScopeSet::Module(ns, module.to_module()),
349                    parent_scope,
350                    finalize.map(|finalize| Finalize { used: Used::Scope, ..finalize }),
351                    ignore_decl,
352                    None,
353                )
354            {
355                // The ident resolves to an item in a block.
356                return Some(LateDecl::Decl(binding));
357            } else if let RibKind::Module(module) = rib.kind {
358                // Encountered a module item, abandon ribs and look into that module and preludes.
359                let parent_scope = &ParentScope { module: module.to_module(), ..*parent_scope };
360                let finalize = finalize.map(|f| Finalize { stage: Stage::Late, ..f });
361                return self
362                    .cm()
363                    .resolve_ident_in_scope_set(
364                        orig_ident,
365                        ScopeSet::All(ns),
366                        parent_scope,
367                        finalize,
368                        ignore_decl,
369                        None,
370                    )
371                    .ok()
372                    .map(LateDecl::Decl);
373            }
374
375            if let RibKind::MacroDefinition(def) = rib.kind
376                && def == self.macro_def(ident.span.ctxt())
377            {
378                // If an invocation of this macro created `ident`, give up on `ident`
379                // and switch to `ident`'s source from the macro definition.
380                ident.span.remove_mark();
381            }
382        }
383
384        unreachable!()
385    }
386
387    /// Resolve an identifier in the specified set of scopes.
388    pub(crate) fn resolve_ident_in_scope_set<'r>(
389        self: CmResolver<'r, 'ra, 'tcx>,
390        orig_ident: Ident,
391        scope_set: ScopeSet<'ra>,
392        parent_scope: &ParentScope<'ra>,
393        finalize: Option<Finalize>,
394        ignore_decl: Option<Decl<'ra>>,
395        ignore_import: Option<Import<'ra>>,
396    ) -> Result<Decl<'ra>, Determinacy> {
397        self.resolve_ident_in_scope_set_inner(
398            IdentKey::new(orig_ident),
399            orig_ident.span,
400            scope_set,
401            parent_scope,
402            finalize,
403            ignore_decl,
404            ignore_import,
405        )
406    }
407
408    fn resolve_ident_in_scope_set_inner<'r>(
409        self: CmResolver<'r, 'ra, 'tcx>,
410        ident: IdentKey,
411        orig_ident_span: Span,
412        scope_set: ScopeSet<'ra>,
413        parent_scope: &ParentScope<'ra>,
414        finalize: Option<Finalize>,
415        ignore_decl: Option<Decl<'ra>>,
416        ignore_import: Option<Import<'ra>>,
417    ) -> Result<Decl<'ra>, Determinacy> {
418        // Make sure `self`, `super` etc produce an error when passed to here.
419        if !#[allow(non_exhaustive_omitted_patterns)] match scope_set {
    ScopeSet::Module(..) => true,
    _ => false,
}matches!(scope_set, ScopeSet::Module(..)) && ident.name.is_path_segment_keyword() {
420            return Err(Determinacy::Determined);
421        }
422
423        let (ns, macro_kind) = match scope_set {
424            ScopeSet::All(ns)
425            | ScopeSet::Module(ns, _)
426            | ScopeSet::ModuleAndExternPrelude(ns, _) => (ns, None),
427            ScopeSet::ExternPrelude => (TypeNS, None),
428            ScopeSet::Macro(macro_kind) => (MacroNS, Some(macro_kind)),
429        };
430        let derive_fallback_lint_id = match finalize {
431            Some(Finalize { node_id, stage: Stage::Late, .. }) => Some(node_id),
432            _ => None,
433        };
434
435        // This is *the* result, resolution from the scope closest to the resolved identifier.
436        // However, sometimes this result is "weak" because it comes from a glob import or
437        // a macro expansion, and in this case it cannot shadow names from outer scopes, e.g.
438        // mod m { ... } // solution in outer scope
439        // {
440        //     use prefix::*; // imports another `m` - innermost solution
441        //                    // weak, cannot shadow the outer `m`, need to report ambiguity error
442        //     m::mac!();
443        // }
444        // So we have to save the innermost solution and continue searching in outer scopes
445        // to detect potential ambiguities.
446        let mut innermost_results: SmallVec<[(Decl<'_>, Scope<'_>); 2]> = SmallVec::new();
447        let mut determinacy = Determinacy::Determined;
448
449        // Go through all the scopes and try to resolve the name.
450        let break_result = self.visit_scopes(
451            scope_set,
452            parent_scope,
453            ident.ctxt,
454            orig_ident_span,
455            derive_fallback_lint_id,
456            |mut this, scope, use_prelude, ctxt| {
457                let ident = IdentKey { name: ident.name, ctxt };
458                let res = match this.reborrow().resolve_ident_in_scope(
459                    ident,
460                    orig_ident_span,
461                    ns,
462                    scope,
463                    use_prelude,
464                    scope_set,
465                    parent_scope,
466                    // Shadowed decls don't need to be marked as used or non-speculatively loaded.
467                    if innermost_results.is_empty() { finalize } else { None },
468                    ignore_decl,
469                    ignore_import,
470                ) {
471                    Ok(decl) => Ok(decl),
472                    // We can break with an error at this step, it means we cannot determine the
473                    // resolution right now, but we must block and wait until we can, instead of
474                    // considering outer scopes. Although there's no need to do that if we already
475                    // have a better solution.
476                    Err(ControlFlow::Break(determinacy)) if innermost_results.is_empty() => {
477                        return ControlFlow::Break(Err(determinacy));
478                    }
479                    Err(determinacy) => Err(determinacy.into_value()),
480                };
481                match res {
482                    Ok(decl) if sub_namespace_match(decl.macro_kinds(), macro_kind) => {
483                        // Below we report various ambiguity errors.
484                        // We do not need to report them if we are either in speculative resolution,
485                        // or in late resolution when everything is already imported and expanded
486                        // and no ambiguities exist.
487                        let import = match finalize {
488                            None | Some(Finalize { stage: Stage::Late, .. }) => {
489                                return ControlFlow::Break(Ok(decl));
490                            }
491                            Some(Finalize { import, .. }) => import,
492                        };
493                        this.get_mut().maybe_push_glob_vs_glob_vis_ambiguity(
494                            ident,
495                            orig_ident_span,
496                            decl,
497                            import,
498                        );
499
500                        if let Some(&(innermost_decl, _)) = innermost_results.first() {
501                            // Found another solution, if the first one was "weak", report an error.
502                            if this.get_mut().maybe_push_ambiguity(
503                                ident,
504                                orig_ident_span,
505                                ns,
506                                scope_set,
507                                parent_scope,
508                                decl,
509                                scope,
510                                &innermost_results,
511                                import,
512                            ) {
513                                // No need to search for more potential ambiguities, one is enough.
514                                return ControlFlow::Break(Ok(innermost_decl));
515                            }
516                        }
517
518                        innermost_results.push((decl, scope));
519                    }
520                    Ok(_) | Err(Determinacy::Determined) => {}
521                    Err(Determinacy::Undetermined) => determinacy = Determinacy::Undetermined,
522                }
523
524                ControlFlow::Continue(())
525            },
526        );
527
528        // Scope visiting returned some result early.
529        if let Some(break_result) = break_result {
530            return break_result;
531        }
532
533        // Scope visiting walked all the scopes and maybe found something in one of them.
534        match innermost_results.first() {
535            Some(&(decl, ..)) => Ok(decl),
536            None => Err(determinacy),
537        }
538    }
539
540    fn resolve_ident_in_scope<'r>(
541        mut self: CmResolver<'r, 'ra, 'tcx>,
542        ident: IdentKey,
543        orig_ident_span: Span,
544        ns: Namespace,
545        scope: Scope<'ra>,
546        use_prelude: UsePrelude,
547        scope_set: ScopeSet<'ra>,
548        parent_scope: &ParentScope<'ra>,
549        finalize: Option<Finalize>,
550        ignore_decl: Option<Decl<'ra>>,
551        ignore_import: Option<Import<'ra>>,
552    ) -> Result<Decl<'ra>, ControlFlow<Determinacy, Determinacy>> {
553        let ret = match scope {
554            Scope::DeriveHelpers(expn_id) => {
555                if let Some(decl) = self
556                    .helper_attrs
557                    .get(&expn_id)
558                    .and_then(|attrs| attrs.iter().rfind(|(i, ..)| ident == *i).map(|(.., d)| *d))
559                {
560                    Ok(decl)
561                } else {
562                    Err(Determinacy::Determined)
563                }
564            }
565            Scope::DeriveHelpersCompat => {
566                let mut result = Err(Determinacy::Determined);
567                for derive in parent_scope.derives {
568                    let parent_scope = &ParentScope { derives: &[], ..*parent_scope };
569                    match self.reborrow().resolve_derive_macro_path(
570                        derive,
571                        parent_scope,
572                        false,
573                        ignore_import,
574                    ) {
575                        Ok((Some(ext), _)) => {
576                            if ext.helper_attrs.contains(&ident.name) {
577                                let decl = self.arenas.new_pub_def_decl(
578                                    Res::NonMacroAttr(NonMacroAttrKind::DeriveHelperCompat),
579                                    derive.span,
580                                    LocalExpnId::ROOT,
581                                );
582                                result = Ok(decl);
583                                break;
584                            }
585                        }
586                        Ok(_) | Err(Determinacy::Determined) => {}
587                        Err(Determinacy::Undetermined) => result = Err(Determinacy::Undetermined),
588                    }
589                }
590                result
591            }
592            Scope::MacroRules(macro_rules_scope) => match macro_rules_scope.get() {
593                MacroRulesScope::Def(macro_rules_def) if ident == macro_rules_def.ident => {
594                    Ok(macro_rules_def.decl)
595                }
596                MacroRulesScope::Invocation(_) => Err(Determinacy::Undetermined),
597                _ => Err(Determinacy::Determined),
598            },
599            Scope::ModuleNonGlobs(module, derive_fallback_lint_id) => {
600                let (adjusted_parent_scope, adjusted_finalize) = if #[allow(non_exhaustive_omitted_patterns)] match scope_set {
    ScopeSet::Module(..) | ScopeSet::ModuleAndExternPrelude(..) => true,
    _ => false,
}matches!(
601                    scope_set,
602                    ScopeSet::Module(..) | ScopeSet::ModuleAndExternPrelude(..)
603                ) {
604                    (parent_scope, finalize)
605                } else {
606                    (
607                        &ParentScope { module, ..*parent_scope },
608                        finalize.map(|f| Finalize { used: Used::Scope, ..f }),
609                    )
610                };
611                let decl = self.reborrow().resolve_ident_in_module_non_globs_unadjusted(
612                    module,
613                    ident,
614                    orig_ident_span,
615                    ns,
616                    adjusted_parent_scope,
617                    if #[allow(non_exhaustive_omitted_patterns)] match scope_set {
    ScopeSet::Module(..) => true,
    _ => false,
}matches!(scope_set, ScopeSet::Module(..)) {
618                        Shadowing::Unrestricted
619                    } else {
620                        Shadowing::Restricted
621                    },
622                    adjusted_finalize,
623                    ignore_decl,
624                    ignore_import,
625                );
626                match decl {
627                    Ok(decl) => {
628                        if let Some(lint_id) = derive_fallback_lint_id {
629                            self.get_mut().lint_buffer.buffer_lint(
630                                PROC_MACRO_DERIVE_RESOLUTION_FALLBACK,
631                                lint_id,
632                                orig_ident_span,
633                                errors::ProcMacroDeriveResolutionFallback {
634                                    span: orig_ident_span,
635                                    ns_descr: ns.descr(),
636                                    ident: ident.name,
637                                },
638                            );
639                        }
640                        Ok(decl)
641                    }
642                    Err(ControlFlow::Continue(determinacy)) => Err(determinacy),
643                    Err(ControlFlow::Break(..)) => return decl,
644                }
645            }
646            Scope::ModuleGlobs(module, _) if !module.is_local() => {
647                // Fast path: external module decoding only creates non-glob declarations.
648                Err(Determined)
649            }
650            Scope::ModuleGlobs(module, derive_fallback_lint_id) => {
651                let (adjusted_parent_scope, adjusted_finalize) = if #[allow(non_exhaustive_omitted_patterns)] match scope_set {
    ScopeSet::Module(..) | ScopeSet::ModuleAndExternPrelude(..) => true,
    _ => false,
}matches!(
652                    scope_set,
653                    ScopeSet::Module(..) | ScopeSet::ModuleAndExternPrelude(..)
654                ) {
655                    (parent_scope, finalize)
656                } else {
657                    (
658                        &ParentScope { module, ..*parent_scope },
659                        finalize.map(|f| Finalize { used: Used::Scope, ..f }),
660                    )
661                };
662                let binding = self.reborrow().resolve_ident_in_module_globs_unadjusted(
663                    module.expect_local(),
664                    ident,
665                    orig_ident_span,
666                    ns,
667                    adjusted_parent_scope,
668                    if #[allow(non_exhaustive_omitted_patterns)] match scope_set {
    ScopeSet::Module(..) => true,
    _ => false,
}matches!(scope_set, ScopeSet::Module(..)) {
669                        Shadowing::Unrestricted
670                    } else {
671                        Shadowing::Restricted
672                    },
673                    adjusted_finalize,
674                    ignore_decl,
675                    ignore_import,
676                );
677                match binding {
678                    Ok(binding) => {
679                        if let Some(lint_id) = derive_fallback_lint_id {
680                            self.get_mut().lint_buffer.buffer_lint(
681                                PROC_MACRO_DERIVE_RESOLUTION_FALLBACK,
682                                lint_id,
683                                orig_ident_span,
684                                errors::ProcMacroDeriveResolutionFallback {
685                                    span: orig_ident_span,
686                                    ns_descr: ns.descr(),
687                                    ident: ident.name,
688                                },
689                            );
690                        }
691                        Ok(binding)
692                    }
693                    Err(ControlFlow::Continue(determinacy)) => Err(determinacy),
694                    Err(ControlFlow::Break(..)) => return binding,
695                }
696            }
697            Scope::MacroUsePrelude => match self.macro_use_prelude.get(&ident.name).cloned() {
698                Some(decl) => Ok(decl),
699                None => Err(Determinacy::determined(!self.graph_root.has_unexpanded_invocations())),
700            },
701            Scope::BuiltinAttrs => match self.builtin_attr_decls.get(&ident.name) {
702                Some(decl) => Ok(*decl),
703                None => Err(Determinacy::Determined),
704            },
705            Scope::ExternPreludeItems => {
706                match self.reborrow().extern_prelude_get_item(
707                    ident,
708                    orig_ident_span,
709                    finalize.is_some(),
710                ) {
711                    Some(decl) => Ok(decl),
712                    None => {
713                        Err(Determinacy::determined(!self.graph_root.has_unexpanded_invocations()))
714                    }
715                }
716            }
717            Scope::ExternPreludeFlags => {
718                match self.extern_prelude_get_flag(ident, orig_ident_span, finalize.is_some()) {
719                    Some(decl) => Ok(decl),
720                    None => Err(Determinacy::Determined),
721                }
722            }
723            Scope::ToolPrelude => match self.registered_tool_decls.get(&ident) {
724                Some(decl) => Ok(*decl),
725                None => Err(Determinacy::Determined),
726            },
727            Scope::StdLibPrelude => {
728                let mut result = Err(Determinacy::Determined);
729                if let Some(prelude) = self.prelude
730                    && let Ok(decl) = self.reborrow().resolve_ident_in_scope_set_inner(
731                        ident,
732                        orig_ident_span,
733                        ScopeSet::Module(ns, prelude),
734                        parent_scope,
735                        None,
736                        ignore_decl,
737                        ignore_import,
738                    )
739                    && (#[allow(non_exhaustive_omitted_patterns)] match use_prelude {
    UsePrelude::Yes => true,
    _ => false,
}matches!(use_prelude, UsePrelude::Yes) || self.is_builtin_macro(decl.res()))
740                {
741                    result = Ok(decl)
742                }
743
744                result
745            }
746            Scope::BuiltinTypes => match self.builtin_type_decls.get(&ident.name) {
747                Some(decl) => {
748                    if #[allow(non_exhaustive_omitted_patterns)] match ident.name {
    sym::f16 => true,
    _ => false,
}matches!(ident.name, sym::f16)
749                        && !self.tcx.features().f16()
750                        && !orig_ident_span.allows_unstable(sym::f16)
751                        && finalize.is_some()
752                    {
753                        feature_err(
754                            self.tcx.sess,
755                            sym::f16,
756                            orig_ident_span,
757                            "the type `f16` is unstable",
758                        )
759                        .emit();
760                    }
761                    if #[allow(non_exhaustive_omitted_patterns)] match ident.name {
    sym::f128 => true,
    _ => false,
}matches!(ident.name, sym::f128)
762                        && !self.tcx.features().f128()
763                        && !orig_ident_span.allows_unstable(sym::f128)
764                        && finalize.is_some()
765                    {
766                        feature_err(
767                            self.tcx.sess,
768                            sym::f128,
769                            orig_ident_span,
770                            "the type `f128` is unstable",
771                        )
772                        .emit();
773                    }
774                    Ok(*decl)
775                }
776                None => Err(Determinacy::Determined),
777            },
778        };
779
780        ret.map_err(ControlFlow::Continue)
781    }
782
783    fn maybe_push_glob_vs_glob_vis_ambiguity(
784        &mut self,
785        ident: IdentKey,
786        orig_ident_span: Span,
787        decl: Decl<'ra>,
788        import: Option<ImportSummary>,
789    ) {
790        let Some(import) = import else { return };
791        let vis1 = self.import_decl_vis(decl, import);
792        let vis2 = self.import_decl_vis_ext(decl, import, true);
793        if vis1 != vis2 {
794            self.ambiguity_errors.push(AmbiguityError {
795                kind: AmbiguityKind::GlobVsGlob,
796                ambig_vis: Some((vis1, vis2)),
797                ident: ident.orig(orig_ident_span),
798                b1: decl.ambiguity_vis_max.get().unwrap_or(decl),
799                b2: decl.ambiguity_vis_min.get().unwrap_or(decl),
800                scope1: Scope::ModuleGlobs(decl.parent_module.unwrap(), None),
801                scope2: Scope::ModuleGlobs(decl.parent_module.unwrap(), None),
802                warning: Some(AmbiguityWarning::GlobImport),
803            });
804        }
805    }
806
807    fn maybe_push_ambiguity(
808        &mut self,
809        ident: IdentKey,
810        orig_ident_span: Span,
811        ns: Namespace,
812        scope_set: ScopeSet<'ra>,
813        parent_scope: &ParentScope<'ra>,
814        decl: Decl<'ra>,
815        scope: Scope<'ra>,
816        innermost_results: &[(Decl<'ra>, Scope<'ra>)],
817        import: Option<ImportSummary>,
818    ) -> bool {
819        let (innermost_decl, innermost_scope) = innermost_results[0];
820        let (res, innermost_res) = (decl.res(), innermost_decl.res());
821        let ambig_vis = if res != innermost_res {
822            None
823        } else if let Some(import) = import
824            && let vis1 = self.import_decl_vis(decl, import)
825            && let vis2 = self.import_decl_vis(innermost_decl, import)
826            && vis1 != vis2
827        {
828            Some((vis1, vis2))
829        } else {
830            return false;
831        };
832
833        // FIXME: Use `scope` instead of `res` to detect built-in attrs and derive helpers,
834        // it will exclude imports, make slightly more code legal, and will require lang approval.
835        let module_only = #[allow(non_exhaustive_omitted_patterns)] match scope_set {
    ScopeSet::Module(..) => true,
    _ => false,
}matches!(scope_set, ScopeSet::Module(..));
836        let is_builtin = |res| #[allow(non_exhaustive_omitted_patterns)] match res {
    Res::NonMacroAttr(NonMacroAttrKind::Builtin(..)) => true,
    _ => false,
}matches!(res, Res::NonMacroAttr(NonMacroAttrKind::Builtin(..)));
837        let derive_helper = Res::NonMacroAttr(NonMacroAttrKind::DeriveHelper);
838        let derive_helper_compat = Res::NonMacroAttr(NonMacroAttrKind::DeriveHelperCompat);
839
840        let ambiguity_error_kind = if is_builtin(innermost_res) || is_builtin(res) {
841            Some(AmbiguityKind::BuiltinAttr)
842        } else if innermost_res == derive_helper_compat {
843            Some(AmbiguityKind::DeriveHelper)
844        } else if res == derive_helper_compat && innermost_res != derive_helper {
845            ::rustc_middle::util::bug::span_bug_fmt(orig_ident_span,
    format_args!("impossible inner resolution kind"))span_bug!(orig_ident_span, "impossible inner resolution kind")
846        } else if #[allow(non_exhaustive_omitted_patterns)] match innermost_scope {
    Scope::MacroRules(_) => true,
    _ => false,
}matches!(innermost_scope, Scope::MacroRules(_))
847            && #[allow(non_exhaustive_omitted_patterns)] match scope {
    Scope::ModuleNonGlobs(..) | Scope::ModuleGlobs(..) => true,
    _ => false,
}matches!(scope, Scope::ModuleNonGlobs(..) | Scope::ModuleGlobs(..))
848            && !self.disambiguate_macro_rules_vs_modularized(innermost_decl, decl)
849        {
850            Some(AmbiguityKind::MacroRulesVsModularized)
851        } else if #[allow(non_exhaustive_omitted_patterns)] match scope {
    Scope::MacroRules(_) => true,
    _ => false,
}matches!(scope, Scope::MacroRules(_))
852            && #[allow(non_exhaustive_omitted_patterns)] match innermost_scope {
    Scope::ModuleNonGlobs(..) | Scope::ModuleGlobs(..) => true,
    _ => false,
}matches!(innermost_scope, Scope::ModuleNonGlobs(..) | Scope::ModuleGlobs(..))
853        {
854            // should be impossible because of visitation order in
855            // visit_scopes
856            //
857            // we visit all macro_rules scopes (e.g. textual scope macros)
858            // before we visit any modules (e.g. path-based scope macros)
859            ::rustc_middle::util::bug::span_bug_fmt(orig_ident_span,
    format_args!("ambiguous scoped macro resolutions with path-based scope resolution as first candidate"))span_bug!(
860                orig_ident_span,
861                "ambiguous scoped macro resolutions with path-based \
862                                        scope resolution as first candidate"
863            )
864        } else if innermost_decl.is_glob_import() {
865            Some(AmbiguityKind::GlobVsOuter)
866        } else if !module_only && innermost_decl.may_appear_after(parent_scope.expansion, decl) {
867            Some(AmbiguityKind::MoreExpandedVsOuter)
868        } else if innermost_decl.expansion != LocalExpnId::ROOT
869            && (!module_only || ns == MacroNS)
870            && let Scope::ModuleGlobs(m1, _) = scope
871            && let Scope::ModuleNonGlobs(m2, _) = innermost_scope
872            && m1 == m2
873        {
874            // FIXME: this error is too conservative and technically unnecessary now when module
875            // scope is split into two scopes, at least when not resolving in `ScopeSet::Module`,
876            // remove it with lang team approval.
877            Some(AmbiguityKind::GlobVsExpanded)
878        } else {
879            None
880        };
881
882        if let Some(kind) = ambiguity_error_kind {
883            // Skip ambiguity errors for extern flag bindings "overridden"
884            // by extern item bindings.
885            // FIXME: Remove with lang team approval.
886            let issue_145575_hack = #[allow(non_exhaustive_omitted_patterns)] match scope {
    Scope::ExternPreludeFlags => true,
    _ => false,
}matches!(scope, Scope::ExternPreludeFlags)
887                && innermost_results[1..]
888                    .iter()
889                    .any(|(b, s)| #[allow(non_exhaustive_omitted_patterns)] match s {
    Scope::ExternPreludeItems => true,
    _ => false,
}matches!(s, Scope::ExternPreludeItems) && *b != innermost_decl);
890            // Skip ambiguity errors for nonglob module bindings "overridden"
891            // by glob module bindings in the same module.
892            // FIXME: Remove with lang team approval.
893            let issue_149681_hack = match scope {
894                Scope::ModuleGlobs(m1, _)
895                    if innermost_results[1..]
896                        .iter()
897                        .any(|(_, s)| #[allow(non_exhaustive_omitted_patterns)] match *s {
    Scope::ModuleNonGlobs(m2, _) if m1 == m2 => true,
    _ => false,
}matches!(*s, Scope::ModuleNonGlobs(m2, _) if m1 == m2)) =>
898                {
899                    true
900                }
901                _ => false,
902            };
903
904            if issue_145575_hack || issue_149681_hack {
905                self.issue_145575_hack_applied = true;
906            } else {
907                // Turn ambiguity errors for core vs std panic into warnings.
908                // FIXME: Remove with lang team approval.
909                let is_issue_147319_hack = orig_ident_span.edition() <= Edition::Edition2024
910                    && #[allow(non_exhaustive_omitted_patterns)] match ident.name {
    sym::panic => true,
    _ => false,
}matches!(ident.name, sym::panic)
911                    && #[allow(non_exhaustive_omitted_patterns)] match scope {
    Scope::StdLibPrelude => true,
    _ => false,
}matches!(scope, Scope::StdLibPrelude)
912                    && #[allow(non_exhaustive_omitted_patterns)] match innermost_scope {
    Scope::ModuleGlobs(_, _) => true,
    _ => false,
}matches!(innermost_scope, Scope::ModuleGlobs(_, _))
913                    && ((self.is_specific_builtin_macro(res, sym::std_panic)
914                        && self.is_specific_builtin_macro(innermost_res, sym::core_panic))
915                        || (self.is_specific_builtin_macro(res, sym::core_panic)
916                            && self.is_specific_builtin_macro(innermost_res, sym::std_panic)));
917
918                let warning = if ambig_vis.is_some() {
919                    Some(AmbiguityWarning::GlobImport)
920                } else if is_issue_147319_hack {
921                    Some(AmbiguityWarning::PanicImport)
922                } else {
923                    None
924                };
925
926                self.ambiguity_errors.push(AmbiguityError {
927                    kind,
928                    ambig_vis,
929                    ident: ident.orig(orig_ident_span),
930                    b1: innermost_decl,
931                    b2: decl,
932                    scope1: innermost_scope,
933                    scope2: scope,
934                    warning,
935                });
936                return true;
937            }
938        }
939
940        false
941    }
942
943    #[allow(clippy :: suspicious_else_formatting)]
{
    let __tracing_attr_span;
    let __tracing_attr_guard;
    if ::tracing::Level::DEBUG <= ::tracing::level_filters::STATIC_MAX_LEVEL
                &&
                ::tracing::Level::DEBUG <=
                    ::tracing::level_filters::LevelFilter::current() ||
            { false } {
        __tracing_attr_span =
            {
                use ::tracing::__macro_support::Callsite as _;
                static __CALLSITE: ::tracing::callsite::DefaultCallsite =
                    {
                        static META: ::tracing::Metadata<'static> =
                            {
                                ::tracing_core::metadata::Metadata::new("maybe_resolve_ident_in_module",
                                    "rustc_resolve::ident", ::tracing::Level::DEBUG,
                                    ::tracing_core::__macro_support::Option::Some("compiler/rustc_resolve/src/ident.rs"),
                                    ::tracing_core::__macro_support::Option::Some(943u32),
                                    ::tracing_core::__macro_support::Option::Some("rustc_resolve::ident"),
                                    ::tracing_core::field::FieldSet::new(&["module", "ident",
                                                    "ns", "parent_scope", "ignore_import"],
                                        ::tracing_core::callsite::Identifier(&__CALLSITE)),
                                    ::tracing::metadata::Kind::SPAN)
                            };
                        ::tracing::callsite::DefaultCallsite::new(&META)
                    };
                let mut interest = ::tracing::subscriber::Interest::never();
                if ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::STATIC_MAX_LEVEL &&
                                ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::LevelFilter::current() &&
                            { interest = __CALLSITE.interest(); !interest.is_never() }
                        &&
                        ::tracing::__macro_support::__is_enabled(__CALLSITE.metadata(),
                            interest) {
                    let meta = __CALLSITE.metadata();
                    ::tracing::Span::new(meta,
                        &{
                                #[allow(unused_imports)]
                                use ::tracing::field::{debug, display, Value};
                                let mut iter = meta.fields().iter();
                                meta.fields().value_set(&[(&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&module)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ident)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ns)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&parent_scope)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ignore_import)
                                                            as &dyn Value))])
                            })
                } else {
                    let span =
                        ::tracing::__macro_support::__disabled_span(__CALLSITE.metadata());
                    {};
                    span
                }
            };
        __tracing_attr_guard = __tracing_attr_span.enter();
    }

    #[warn(clippy :: suspicious_else_formatting)]
    {

        #[allow(unknown_lints, unreachable_code, clippy ::
        diverging_sub_expression, clippy :: empty_loop, clippy ::
        let_unit_value, clippy :: let_with_type_underscore, clippy ::
        needless_return, clippy :: unreachable)]
        if false {
            let __tracing_attr_fake_return: Result<Decl<'ra>, Determinacy> =
                loop {};
            return __tracing_attr_fake_return;
        }
        {
            self.resolve_ident_in_module(module, ident, ns, parent_scope,
                None, None, ignore_import)
        }
    }
}#[instrument(level = "debug", skip(self))]
944    pub(crate) fn maybe_resolve_ident_in_module<'r>(
945        self: CmResolver<'r, 'ra, 'tcx>,
946        module: ModuleOrUniformRoot<'ra>,
947        ident: Ident,
948        ns: Namespace,
949        parent_scope: &ParentScope<'ra>,
950        ignore_import: Option<Import<'ra>>,
951    ) -> Result<Decl<'ra>, Determinacy> {
952        self.resolve_ident_in_module(module, ident, ns, parent_scope, None, None, ignore_import)
953    }
954
955    fn resolve_super_in_module(
956        &self,
957        ident: Ident,
958        module: Option<Module<'ra>>,
959        parent_scope: &ParentScope<'ra>,
960    ) -> Option<Module<'ra>> {
961        let mut ctxt = ident.span.ctxt().normalize_to_macros_2_0();
962        module
963            .unwrap_or_else(|| self.resolve_self(&mut ctxt, parent_scope.module))
964            .parent
965            .map(|parent| self.resolve_self(&mut ctxt, parent))
966    }
967
968    pub(crate) fn path_root_is_crate_root(&self, ident: Ident) -> bool {
969        ident.name == kw::PathRoot && ident.span.is_rust_2015() && self.tcx.sess.is_rust_2015()
970    }
971
972    #[allow(clippy :: suspicious_else_formatting)]
{
    let __tracing_attr_span;
    let __tracing_attr_guard;
    if ::tracing::Level::DEBUG <= ::tracing::level_filters::STATIC_MAX_LEVEL
                &&
                ::tracing::Level::DEBUG <=
                    ::tracing::level_filters::LevelFilter::current() ||
            { false } {
        __tracing_attr_span =
            {
                use ::tracing::__macro_support::Callsite as _;
                static __CALLSITE: ::tracing::callsite::DefaultCallsite =
                    {
                        static META: ::tracing::Metadata<'static> =
                            {
                                ::tracing_core::metadata::Metadata::new("resolve_ident_in_module",
                                    "rustc_resolve::ident", ::tracing::Level::DEBUG,
                                    ::tracing_core::__macro_support::Option::Some("compiler/rustc_resolve/src/ident.rs"),
                                    ::tracing_core::__macro_support::Option::Some(972u32),
                                    ::tracing_core::__macro_support::Option::Some("rustc_resolve::ident"),
                                    ::tracing_core::field::FieldSet::new(&["module", "ident",
                                                    "ns", "parent_scope", "finalize", "ignore_decl",
                                                    "ignore_import"],
                                        ::tracing_core::callsite::Identifier(&__CALLSITE)),
                                    ::tracing::metadata::Kind::SPAN)
                            };
                        ::tracing::callsite::DefaultCallsite::new(&META)
                    };
                let mut interest = ::tracing::subscriber::Interest::never();
                if ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::STATIC_MAX_LEVEL &&
                                ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::LevelFilter::current() &&
                            { interest = __CALLSITE.interest(); !interest.is_never() }
                        &&
                        ::tracing::__macro_support::__is_enabled(__CALLSITE.metadata(),
                            interest) {
                    let meta = __CALLSITE.metadata();
                    ::tracing::Span::new(meta,
                        &{
                                #[allow(unused_imports)]
                                use ::tracing::field::{debug, display, Value};
                                let mut iter = meta.fields().iter();
                                meta.fields().value_set(&[(&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&module)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ident)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ns)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&parent_scope)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&finalize)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ignore_decl)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ignore_import)
                                                            as &dyn Value))])
                            })
                } else {
                    let span =
                        ::tracing::__macro_support::__disabled_span(__CALLSITE.metadata());
                    {};
                    span
                }
            };
        __tracing_attr_guard = __tracing_attr_span.enter();
    }

    #[warn(clippy :: suspicious_else_formatting)]
    {

        #[allow(unknown_lints, unreachable_code, clippy ::
        diverging_sub_expression, clippy :: empty_loop, clippy ::
        let_unit_value, clippy :: let_with_type_underscore, clippy ::
        needless_return, clippy :: unreachable)]
        if false {
            let __tracing_attr_fake_return: Result<Decl<'ra>, Determinacy> =
                loop {};
            return __tracing_attr_fake_return;
        }
        {
            match module {
                ModuleOrUniformRoot::Module(module) => {
                    if ns == TypeNS {
                        if ident.name == kw::SelfLower {
                            return Ok(module.self_decl.unwrap());
                        }
                        if ident.name == kw::Super &&
                                let Some(module) =
                                    self.resolve_super_in_module(ident, Some(module),
                                        parent_scope) {
                            return Ok(module.self_decl.unwrap());
                        }
                    }
                    let (ident_key, def) =
                        IdentKey::new_adjusted(ident, module.expansion);
                    let adjusted_parent_scope =
                        match def {
                            Some(def) =>
                                ParentScope {
                                    module: self.expn_def_scope(def),
                                    ..*parent_scope
                                },
                            None => *parent_scope,
                        };
                    self.resolve_ident_in_scope_set_inner(ident_key, ident.span,
                        ScopeSet::Module(ns, module), &adjusted_parent_scope,
                        finalize, ignore_decl, ignore_import)
                }
                ModuleOrUniformRoot::OpenModule(sym) => {
                    let open_ns_name =
                        ::alloc::__export::must_use({
                                ::alloc::fmt::format(format_args!("{0}::{1}", sym.as_str(),
                                        ident.name))
                            });
                    let ns_ident =
                        IdentKey::with_root_ctxt(Symbol::intern(&open_ns_name));
                    match self.extern_prelude_get_flag(ns_ident, ident.span,
                            finalize.is_some()) {
                        Some(decl) => Ok(decl),
                        None => Err(Determinacy::Determined),
                    }
                }
                ModuleOrUniformRoot::ModuleAndExternPrelude(module) =>
                    self.resolve_ident_in_scope_set(ident,
                        ScopeSet::ModuleAndExternPrelude(ns, module), parent_scope,
                        finalize, ignore_decl, ignore_import),
                ModuleOrUniformRoot::ExternPrelude => {
                    if ns != TypeNS {
                        Err(Determined)
                    } else {
                        self.resolve_ident_in_scope_set_inner(IdentKey::new_adjusted(ident,
                                    ExpnId::root()).0, ident.span, ScopeSet::ExternPrelude,
                            parent_scope, finalize, ignore_decl, ignore_import)
                    }
                }
                ModuleOrUniformRoot::CurrentScope => {
                    if ns == TypeNS {
                        if ident.name == kw::SelfLower {
                            let mut ctxt = ident.span.ctxt().normalize_to_macros_2_0();
                            let module =
                                self.resolve_self(&mut ctxt, parent_scope.module);
                            return Ok(module.self_decl.unwrap());
                        }
                        if ident.name == kw::Super &&
                                let Some(module) =
                                    self.resolve_super_in_module(ident, None, parent_scope) {
                            return Ok(module.self_decl.unwrap());
                        }
                        if ident.name == kw::Crate || ident.name == kw::DollarCrate
                                || self.path_root_is_crate_root(ident) {
                            let module = self.resolve_crate_root(ident);
                            return Ok(module.self_decl.unwrap());
                        } else if ident.name == kw::Super {}
                    }
                    self.resolve_ident_in_scope_set(ident, ScopeSet::All(ns),
                        parent_scope, finalize, ignore_decl, ignore_import)
                }
            }
        }
    }
}#[instrument(level = "debug", skip(self))]
973    pub(crate) fn resolve_ident_in_module<'r>(
974        self: CmResolver<'r, 'ra, 'tcx>,
975        module: ModuleOrUniformRoot<'ra>,
976        ident: Ident,
977        ns: Namespace,
978        parent_scope: &ParentScope<'ra>,
979        finalize: Option<Finalize>,
980        ignore_decl: Option<Decl<'ra>>,
981        ignore_import: Option<Import<'ra>>,
982    ) -> Result<Decl<'ra>, Determinacy> {
983        match module {
984            ModuleOrUniformRoot::Module(module) => {
985                if ns == TypeNS {
986                    if ident.name == kw::SelfLower {
987                        return Ok(module.self_decl.unwrap());
988                    }
989                    if ident.name == kw::Super
990                        && let Some(module) =
991                            self.resolve_super_in_module(ident, Some(module), parent_scope)
992                    {
993                        return Ok(module.self_decl.unwrap());
994                    }
995                }
996
997                let (ident_key, def) = IdentKey::new_adjusted(ident, module.expansion);
998                let adjusted_parent_scope = match def {
999                    Some(def) => ParentScope { module: self.expn_def_scope(def), ..*parent_scope },
1000                    None => *parent_scope,
1001                };
1002                self.resolve_ident_in_scope_set_inner(
1003                    ident_key,
1004                    ident.span,
1005                    ScopeSet::Module(ns, module),
1006                    &adjusted_parent_scope,
1007                    finalize,
1008                    ignore_decl,
1009                    ignore_import,
1010                )
1011            }
1012            ModuleOrUniformRoot::OpenModule(sym) => {
1013                let open_ns_name = format!("{}::{}", sym.as_str(), ident.name);
1014                let ns_ident = IdentKey::with_root_ctxt(Symbol::intern(&open_ns_name));
1015                match self.extern_prelude_get_flag(ns_ident, ident.span, finalize.is_some()) {
1016                    Some(decl) => Ok(decl),
1017                    None => Err(Determinacy::Determined),
1018                }
1019            }
1020            ModuleOrUniformRoot::ModuleAndExternPrelude(module) => self.resolve_ident_in_scope_set(
1021                ident,
1022                ScopeSet::ModuleAndExternPrelude(ns, module),
1023                parent_scope,
1024                finalize,
1025                ignore_decl,
1026                ignore_import,
1027            ),
1028            ModuleOrUniformRoot::ExternPrelude => {
1029                if ns != TypeNS {
1030                    Err(Determined)
1031                } else {
1032                    self.resolve_ident_in_scope_set_inner(
1033                        IdentKey::new_adjusted(ident, ExpnId::root()).0,
1034                        ident.span,
1035                        ScopeSet::ExternPrelude,
1036                        parent_scope,
1037                        finalize,
1038                        ignore_decl,
1039                        ignore_import,
1040                    )
1041                }
1042            }
1043            ModuleOrUniformRoot::CurrentScope => {
1044                if ns == TypeNS {
1045                    if ident.name == kw::SelfLower {
1046                        let mut ctxt = ident.span.ctxt().normalize_to_macros_2_0();
1047                        let module = self.resolve_self(&mut ctxt, parent_scope.module);
1048                        return Ok(module.self_decl.unwrap());
1049                    }
1050                    if ident.name == kw::Super
1051                        && let Some(module) =
1052                            self.resolve_super_in_module(ident, None, parent_scope)
1053                    {
1054                        return Ok(module.self_decl.unwrap());
1055                    }
1056                    if ident.name == kw::Crate
1057                        || ident.name == kw::DollarCrate
1058                        || self.path_root_is_crate_root(ident)
1059                    {
1060                        let module = self.resolve_crate_root(ident);
1061                        return Ok(module.self_decl.unwrap());
1062                    } else if ident.name == kw::Super {
1063                        // FIXME: Implement these with renaming requirements so that e.g.
1064                        // `use super;` doesn't work, but `use super as name;` does.
1065                        // Fall through here to get an error from `early_resolve_...`.
1066                    }
1067                }
1068
1069                self.resolve_ident_in_scope_set(
1070                    ident,
1071                    ScopeSet::All(ns),
1072                    parent_scope,
1073                    finalize,
1074                    ignore_decl,
1075                    ignore_import,
1076                )
1077            }
1078        }
1079    }
1080
1081    /// Attempts to resolve `ident` in namespace `ns` of non-glob bindings in `module`.
1082    fn resolve_ident_in_module_non_globs_unadjusted<'r>(
1083        mut self: CmResolver<'r, 'ra, 'tcx>,
1084        module: Module<'ra>,
1085        ident: IdentKey,
1086        orig_ident_span: Span,
1087        ns: Namespace,
1088        parent_scope: &ParentScope<'ra>,
1089        shadowing: Shadowing,
1090        finalize: Option<Finalize>,
1091        // This binding should be ignored during in-module resolution, so that we don't get
1092        // "self-confirming" import resolutions during import validation and checking.
1093        ignore_decl: Option<Decl<'ra>>,
1094        ignore_import: Option<Import<'ra>>,
1095    ) -> Result<Decl<'ra>, ControlFlow<Determinacy, Determinacy>> {
1096        let key = BindingKey::new(ident, ns);
1097        // `try_borrow_mut` is required to ensure exclusive access, even if the resulting binding
1098        // doesn't need to be mutable. It will fail when there is a cycle of imports, and without
1099        // the exclusive access infinite recursion will crash the compiler with stack overflow.
1100        let resolution = &*self
1101            .resolution_or_default(module, key, orig_ident_span)
1102            .try_borrow_mut_unchecked()
1103            .map_err(|_| ControlFlow::Continue(Determined))?;
1104
1105        let binding = resolution.non_glob_decl.filter(|b| Some(*b) != ignore_decl);
1106
1107        if let Some(finalize) = finalize {
1108            return self.get_mut().finalize_module_binding(
1109                ident,
1110                orig_ident_span,
1111                binding,
1112                parent_scope,
1113                finalize,
1114                shadowing,
1115            );
1116        }
1117
1118        // Items and single imports are not shadowable, if we have one, then it's determined.
1119        if let Some(binding) = binding {
1120            let accessible = self.is_accessible_from(binding.vis(), parent_scope.module);
1121            return if accessible { Ok(binding) } else { Err(ControlFlow::Break(Determined)) };
1122        }
1123
1124        // In extern modules everything is determined from the start.
1125        if !module.is_local() {
1126            return Err(ControlFlow::Continue(Determined));
1127        };
1128
1129        // Check if one of single imports can still define the name, block if it can.
1130        if self.reborrow().single_import_can_define_name(
1131            &resolution,
1132            None,
1133            ns,
1134            ignore_import,
1135            ignore_decl,
1136            parent_scope,
1137        ) {
1138            return Err(ControlFlow::Break(Undetermined));
1139        }
1140
1141        // Check if one of unexpanded macros can still define the name.
1142        if module.has_unexpanded_invocations() {
1143            return Err(ControlFlow::Continue(Undetermined));
1144        }
1145
1146        // No resolution and no one else can define the name - determinate error.
1147        Err(ControlFlow::Continue(Determined))
1148    }
1149
1150    /// Attempts to resolve `ident` in namespace `ns` of glob bindings in `module`.
1151    fn resolve_ident_in_module_globs_unadjusted<'r>(
1152        mut self: CmResolver<'r, 'ra, 'tcx>,
1153        module: LocalModule<'ra>,
1154        ident: IdentKey,
1155        orig_ident_span: Span,
1156        ns: Namespace,
1157        parent_scope: &ParentScope<'ra>,
1158        shadowing: Shadowing,
1159        finalize: Option<Finalize>,
1160        ignore_decl: Option<Decl<'ra>>,
1161        ignore_import: Option<Import<'ra>>,
1162    ) -> Result<Decl<'ra>, ControlFlow<Determinacy, Determinacy>> {
1163        let key = BindingKey::new(ident, ns);
1164        // `try_borrow_mut` is required to ensure exclusive access, even if the resulting binding
1165        // doesn't need to be mutable. It will fail when there is a cycle of imports, and without
1166        // the exclusive access infinite recursion will crash the compiler with stack overflow.
1167        let resolution = &*self
1168            .resolution_or_default(module.to_module(), key, orig_ident_span)
1169            .try_borrow_mut_unchecked()
1170            .map_err(|_| ControlFlow::Continue(Determined))?;
1171
1172        let binding = resolution.glob_decl.filter(|b| Some(*b) != ignore_decl);
1173
1174        if let Some(finalize) = finalize {
1175            return self.get_mut().finalize_module_binding(
1176                ident,
1177                orig_ident_span,
1178                binding,
1179                parent_scope,
1180                finalize,
1181                shadowing,
1182            );
1183        }
1184
1185        // Check if one of single imports can still define the name,
1186        // if it can then our result is not determined and can be invalidated.
1187        if self.reborrow().single_import_can_define_name(
1188            &resolution,
1189            binding,
1190            ns,
1191            ignore_import,
1192            ignore_decl,
1193            parent_scope,
1194        ) {
1195            return Err(ControlFlow::Break(Undetermined));
1196        }
1197
1198        // So we have a resolution that's from a glob import. This resolution is determined
1199        // if it cannot be shadowed by some new item/import expanded from a macro.
1200        // This happens either if there are no unexpanded macros, or expanded names cannot
1201        // shadow globs (that happens in macro namespace or with restricted shadowing).
1202        //
1203        // Additionally, any macro in any module can plant names in the root module if it creates
1204        // `macro_export` macros, so the root module effectively has unresolved invocations if any
1205        // module has unresolved invocations.
1206        // However, it causes resolution/expansion to stuck too often (#53144), so, to make
1207        // progress, we have to ignore those potential unresolved invocations from other modules
1208        // and prohibit access to macro-expanded `macro_export` macros instead (unless restricted
1209        // shadowing is enabled, see `macro_expanded_macro_export_errors`).
1210        if let Some(binding) = binding {
1211            return if binding.determined() || ns == MacroNS || shadowing == Shadowing::Restricted {
1212                let accessible = self.is_accessible_from(binding.vis(), parent_scope.module);
1213                if accessible { Ok(binding) } else { Err(ControlFlow::Break(Determined)) }
1214            } else {
1215                Err(ControlFlow::Break(Undetermined))
1216            };
1217        }
1218
1219        // Now we are in situation when new item/import can appear only from a glob or a macro
1220        // expansion. With restricted shadowing names from globs and macro expansions cannot
1221        // shadow names from outer scopes, so we can freely fallback from module search to search
1222        // in outer scopes. For `resolve_ident_in_scope_set` to continue search in outer
1223        // scopes we return `Undetermined` with `ControlFlow::Continue`.
1224        // Check if one of unexpanded macros can still define the name,
1225        // if it can then our "no resolution" result is not determined and can be invalidated.
1226        if module.has_unexpanded_invocations() {
1227            return Err(ControlFlow::Continue(Undetermined));
1228        }
1229
1230        // Check if one of glob imports can still define the name,
1231        // if it can then our "no resolution" result is not determined and can be invalidated.
1232        for glob_import in module.globs.borrow().iter() {
1233            if ignore_import == Some(*glob_import) {
1234                continue;
1235            }
1236            if !self.is_accessible_from(glob_import.vis, parent_scope.module) {
1237                continue;
1238            }
1239            let module = match glob_import.imported_module.get() {
1240                Some(ModuleOrUniformRoot::Module(module)) => module,
1241                Some(_) => continue,
1242                None => return Err(ControlFlow::Continue(Undetermined)),
1243            };
1244            let tmp_parent_scope;
1245            let (mut adjusted_parent_scope, mut adjusted_ident) = (parent_scope, ident);
1246            match adjusted_ident
1247                .ctxt
1248                .update_unchecked(|ctxt| ctxt.glob_adjust(module.expansion, glob_import.span))
1249            {
1250                Some(Some(def)) => {
1251                    tmp_parent_scope =
1252                        ParentScope { module: self.expn_def_scope(def), ..*parent_scope };
1253                    adjusted_parent_scope = &tmp_parent_scope;
1254                }
1255                Some(None) => {}
1256                None => continue,
1257            };
1258            let result = self.reborrow().resolve_ident_in_scope_set_inner(
1259                adjusted_ident,
1260                orig_ident_span,
1261                ScopeSet::Module(ns, module),
1262                adjusted_parent_scope,
1263                None,
1264                ignore_decl,
1265                ignore_import,
1266            );
1267
1268            match result {
1269                Err(Determined) => continue,
1270                Ok(binding)
1271                    if !self.is_accessible_from(binding.vis(), glob_import.parent_scope.module) =>
1272                {
1273                    continue;
1274                }
1275                Ok(_) | Err(Undetermined) => return Err(ControlFlow::Continue(Undetermined)),
1276            }
1277        }
1278
1279        // No resolution and no one else can define the name - determinate error.
1280        Err(ControlFlow::Continue(Determined))
1281    }
1282
1283    fn finalize_module_binding(
1284        &mut self,
1285        ident: IdentKey,
1286        orig_ident_span: Span,
1287        binding: Option<Decl<'ra>>,
1288        parent_scope: &ParentScope<'ra>,
1289        finalize: Finalize,
1290        shadowing: Shadowing,
1291    ) -> Result<Decl<'ra>, ControlFlow<Determinacy, Determinacy>> {
1292        let Finalize { path_span, report_private, used, root_span, .. } = finalize;
1293
1294        let Some(binding) = binding else {
1295            return Err(ControlFlow::Continue(Determined));
1296        };
1297
1298        let ident = ident.orig(orig_ident_span);
1299        if !self.is_accessible_from(binding.vis(), parent_scope.module) {
1300            if report_private {
1301                self.privacy_errors.push(PrivacyError {
1302                    ident,
1303                    decl: binding,
1304                    dedup_span: path_span,
1305                    outermost_res: None,
1306                    source: None,
1307                    parent_scope: *parent_scope,
1308                    single_nested: path_span != root_span,
1309                });
1310            } else {
1311                return Err(ControlFlow::Break(Determined));
1312            }
1313        }
1314
1315        if shadowing == Shadowing::Unrestricted
1316            && binding.expansion != LocalExpnId::ROOT
1317            && let DeclKind::Import { import, .. } = binding.kind
1318            && #[allow(non_exhaustive_omitted_patterns)] match import.kind {
    ImportKind::MacroExport => true,
    _ => false,
}matches!(import.kind, ImportKind::MacroExport)
1319        {
1320            self.macro_expanded_macro_export_errors.insert((path_span, binding.span));
1321        }
1322
1323        self.record_use(ident, binding, used);
1324        return Ok(binding);
1325    }
1326
1327    // Checks if a single import can define the `Ident` corresponding to `binding`.
1328    // This is used to check whether we can definitively accept a glob as a resolution.
1329    fn single_import_can_define_name<'r>(
1330        mut self: CmResolver<'r, 'ra, 'tcx>,
1331        resolution: &NameResolution<'ra>,
1332        binding: Option<Decl<'ra>>,
1333        ns: Namespace,
1334        ignore_import: Option<Import<'ra>>,
1335        ignore_decl: Option<Decl<'ra>>,
1336        parent_scope: &ParentScope<'ra>,
1337    ) -> bool {
1338        for single_import in &resolution.single_imports {
1339            if let Some(decl) = resolution.non_glob_decl
1340                && let DeclKind::Import { import, .. } = decl.kind
1341                && import == *single_import
1342            {
1343                // Single import has already defined the name and we are aware of it,
1344                // no need to block the globs.
1345                continue;
1346            }
1347            if ignore_import == Some(*single_import) {
1348                continue;
1349            }
1350            if !self.is_accessible_from(single_import.vis, parent_scope.module) {
1351                continue;
1352            }
1353            if let Some(ignored) = ignore_decl
1354                && let DeclKind::Import { import, .. } = ignored.kind
1355                && import == *single_import
1356            {
1357                continue;
1358            }
1359
1360            let Some(module) = single_import.imported_module.get() else {
1361                return true;
1362            };
1363            let ImportKind::Single { source, target, decls, .. } = &single_import.kind else {
1364                ::core::panicking::panic("internal error: entered unreachable code");unreachable!();
1365            };
1366            if source != target {
1367                if decls.iter().all(|d| d.get().decl().is_none()) {
1368                    return true;
1369                } else if decls[ns].get().decl().is_none() && binding.is_some() {
1370                    return true;
1371                }
1372            }
1373
1374            match self.reborrow().resolve_ident_in_module(
1375                module,
1376                *source,
1377                ns,
1378                &single_import.parent_scope,
1379                None,
1380                ignore_decl,
1381                None,
1382            ) {
1383                Err(Determined) => continue,
1384                Ok(binding)
1385                    if !self
1386                        .is_accessible_from(binding.vis(), single_import.parent_scope.module) =>
1387                {
1388                    continue;
1389                }
1390                Ok(_) | Err(Undetermined) => return true,
1391            }
1392        }
1393
1394        false
1395    }
1396
1397    /// Validate a local resolution (from ribs).
1398    #[allow(clippy :: suspicious_else_formatting)]
{
    let __tracing_attr_span;
    let __tracing_attr_guard;
    if ::tracing::Level::DEBUG <= ::tracing::level_filters::STATIC_MAX_LEVEL
                &&
                ::tracing::Level::DEBUG <=
                    ::tracing::level_filters::LevelFilter::current() ||
            { false } {
        __tracing_attr_span =
            {
                use ::tracing::__macro_support::Callsite as _;
                static __CALLSITE: ::tracing::callsite::DefaultCallsite =
                    {
                        static META: ::tracing::Metadata<'static> =
                            {
                                ::tracing_core::metadata::Metadata::new("validate_res_from_ribs",
                                    "rustc_resolve::ident", ::tracing::Level::DEBUG,
                                    ::tracing_core::__macro_support::Option::Some("compiler/rustc_resolve/src/ident.rs"),
                                    ::tracing_core::__macro_support::Option::Some(1398u32),
                                    ::tracing_core::__macro_support::Option::Some("rustc_resolve::ident"),
                                    ::tracing_core::field::FieldSet::new(&["rib_index",
                                                    "rib_ident", "res", "finalize", "original_rib_ident_def",
                                                    "diag_metadata"],
                                        ::tracing_core::callsite::Identifier(&__CALLSITE)),
                                    ::tracing::metadata::Kind::SPAN)
                            };
                        ::tracing::callsite::DefaultCallsite::new(&META)
                    };
                let mut interest = ::tracing::subscriber::Interest::never();
                if ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::STATIC_MAX_LEVEL &&
                                ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::LevelFilter::current() &&
                            { interest = __CALLSITE.interest(); !interest.is_never() }
                        &&
                        ::tracing::__macro_support::__is_enabled(__CALLSITE.metadata(),
                            interest) {
                    let meta = __CALLSITE.metadata();
                    ::tracing::Span::new(meta,
                        &{
                                #[allow(unused_imports)]
                                use ::tracing::field::{debug, display, Value};
                                let mut iter = meta.fields().iter();
                                meta.fields().value_set(&[(&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&rib_index as
                                                            &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&rib_ident)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&res)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&finalize)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&original_rib_ident_def)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&diag_metadata)
                                                            as &dyn Value))])
                            })
                } else {
                    let span =
                        ::tracing::__macro_support::__disabled_span(__CALLSITE.metadata());
                    {};
                    span
                }
            };
        __tracing_attr_guard = __tracing_attr_span.enter();
    }

    #[warn(clippy :: suspicious_else_formatting)]
    {

        #[allow(unknown_lints, unreachable_code, clippy ::
        diverging_sub_expression, clippy :: empty_loop, clippy ::
        let_unit_value, clippy :: let_with_type_underscore, clippy ::
        needless_return, clippy :: unreachable)]
        if false {
            let __tracing_attr_fake_return: Res = loop {};
            return __tracing_attr_fake_return;
        }
        {
            {
                use ::tracing::__macro_support::Callsite as _;
                static __CALLSITE: ::tracing::callsite::DefaultCallsite =
                    {
                        static META: ::tracing::Metadata<'static> =
                            {
                                ::tracing_core::metadata::Metadata::new("event compiler/rustc_resolve/src/ident.rs:1409",
                                    "rustc_resolve::ident", ::tracing::Level::DEBUG,
                                    ::tracing_core::__macro_support::Option::Some("compiler/rustc_resolve/src/ident.rs"),
                                    ::tracing_core::__macro_support::Option::Some(1409u32),
                                    ::tracing_core::__macro_support::Option::Some("rustc_resolve::ident"),
                                    ::tracing_core::field::FieldSet::new(&["message"],
                                        ::tracing_core::callsite::Identifier(&__CALLSITE)),
                                    ::tracing::metadata::Kind::EVENT)
                            };
                        ::tracing::callsite::DefaultCallsite::new(&META)
                    };
                let enabled =
                    ::tracing::Level::DEBUG <=
                                ::tracing::level_filters::STATIC_MAX_LEVEL &&
                            ::tracing::Level::DEBUG <=
                                ::tracing::level_filters::LevelFilter::current() &&
                        {
                            let interest = __CALLSITE.interest();
                            !interest.is_never() &&
                                ::tracing::__macro_support::__is_enabled(__CALLSITE.metadata(),
                                    interest)
                        };
                if enabled {
                    (|value_set: ::tracing::field::ValueSet|
                                {
                                    let meta = __CALLSITE.metadata();
                                    ::tracing::Event::dispatch(meta, &value_set);
                                    ;
                                })({
                            #[allow(unused_imports)]
                            use ::tracing::field::{debug, display, Value};
                            let mut iter = __CALLSITE.metadata().fields().iter();
                            __CALLSITE.metadata().fields().value_set(&[(&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                ::tracing::__macro_support::Option::Some(&format_args!("validate_res_from_ribs({0:?})",
                                                                res) as &dyn Value))])
                        });
                } else { ; }
            };
            let ribs = &all_ribs[rib_index + 1..];
            if let RibKind::ForwardGenericParamBan(reason) =
                    all_ribs[rib_index].kind {
                if let Some(span) = finalize {
                    let res_error =
                        if rib_ident.name == kw::SelfUpper {
                            ResolutionError::ForwardDeclaredSelf(reason)
                        } else {
                            ResolutionError::ForwardDeclaredGenericParam(rib_ident.name,
                                reason)
                        };
                    self.report_error(span, res_error);
                }
                match (&res, &Res::Err) {
                    (left_val, right_val) => {
                        if !(*left_val == *right_val) {
                            let kind = ::core::panicking::AssertKind::Eq;
                            ::core::panicking::assert_failed(kind, &*left_val,
                                &*right_val, ::core::option::Option::None);
                        }
                    }
                };
                return Res::Err;
            }
            match res {
                Res::Local(_) => {
                    use ResolutionError::*;
                    let mut res_err = None;
                    for rib in ribs {
                        match rib.kind {
                            RibKind::Normal | RibKind::Block(..) |
                                RibKind::FnOrCoroutine | RibKind::Module(..) |
                                RibKind::MacroDefinition(..) |
                                RibKind::ForwardGenericParamBan(_) => {}
                            RibKind::Item(..) | RibKind::AssocItem => {
                                if let Some(span) = finalize {
                                    res_err =
                                        Some((span, CannotCaptureDynamicEnvironmentInFnItem));
                                }
                            }
                            RibKind::ConstantItem(_, item) => {
                                if let Some(span) = finalize {
                                    let (span, resolution_error) =
                                        match item {
                                            None if rib_ident.name == kw::SelfLower => {
                                                (span, LowercaseSelf)
                                            }
                                            None => {
                                                let sm = self.tcx.sess.source_map();
                                                let type_span =
                                                    match sm.span_followed_by(original_rib_ident_def.span, ":")
                                                        {
                                                        None => { Some(original_rib_ident_def.span.shrink_to_hi()) }
                                                        Some(_) => None,
                                                    };
                                                (rib_ident.span,
                                                    AttemptToUseNonConstantValueInConstant {
                                                        ident: original_rib_ident_def,
                                                        suggestion: "const",
                                                        current: "let",
                                                        type_span,
                                                    })
                                            }
                                            Some((ident, kind)) =>
                                                (span,
                                                    AttemptToUseNonConstantValueInConstant {
                                                        ident,
                                                        suggestion: "let",
                                                        current: kind.as_str(),
                                                        type_span: None,
                                                    }),
                                        };
                                    self.report_error(span, resolution_error);
                                }
                                return Res::Err;
                            }
                            RibKind::ConstParamTy => {
                                if let Some(span) = finalize {
                                    self.report_error(span,
                                        ParamInTyOfConstParam { name: rib_ident.name });
                                }
                                return Res::Err;
                            }
                            RibKind::InlineAsmSym => {
                                if let Some(span) = finalize {
                                    self.report_error(span, InvalidAsmSym);
                                }
                                return Res::Err;
                            }
                        }
                    }
                    if let Some((span, res_err)) = res_err {
                        self.report_error(span, res_err);
                        return Res::Err;
                    }
                }
                Res::Def(DefKind::TyParam, _) | Res::SelfTyParam { .. } |
                    Res::SelfTyAlias { .. } => {
                    for rib in ribs {
                        let (has_generic_params, def_kind) =
                            match rib.kind {
                                RibKind::Normal | RibKind::Block(..) |
                                    RibKind::FnOrCoroutine | RibKind::Module(..) |
                                    RibKind::MacroDefinition(..) | RibKind::InlineAsmSym |
                                    RibKind::AssocItem | RibKind::ForwardGenericParamBan(_) => {
                                    continue;
                                }
                                RibKind::ConstParamTy => {
                                    if !self.tcx.features().generic_const_parameter_types() {
                                        if let Some(span) = finalize {
                                            self.report_error(span,
                                                ResolutionError::ParamInTyOfConstParam {
                                                    name: rib_ident.name,
                                                });
                                        }
                                        return Res::Err;
                                    } else { continue; }
                                }
                                RibKind::ConstantItem(trivial, _) => {
                                    if let ConstantHasGenerics::No(cause) = trivial &&
                                            !#[allow(non_exhaustive_omitted_patterns)] match res {
                                                    Res::SelfTyAlias { .. } => true,
                                                    _ => false,
                                                } {
                                        if let Some(span) = finalize {
                                            let error =
                                                match cause {
                                                    NoConstantGenericsReason::IsEnumDiscriminant => {
                                                        ResolutionError::ParamInEnumDiscriminant {
                                                            name: rib_ident.name,
                                                            param_kind: ParamKindInEnumDiscriminant::Type,
                                                        }
                                                    }
                                                    NoConstantGenericsReason::NonTrivialConstArg => {
                                                        ResolutionError::ParamInNonTrivialAnonConst {
                                                            is_gca: self.tcx.features().generic_const_args(),
                                                            name: rib_ident.name,
                                                            param_kind: ParamKindInNonTrivialAnonConst::Type,
                                                        }
                                                    }
                                                };
                                            let _: ErrorGuaranteed = self.report_error(span, error);
                                        }
                                        return Res::Err;
                                    }
                                    continue;
                                }
                                RibKind::Item(has_generic_params, def_kind) => {
                                    (has_generic_params, def_kind)
                                }
                            };
                        if let Some(span) = finalize {
                            let item =
                                if let Some(diag_metadata) = diag_metadata &&
                                        let Some(current_item) = diag_metadata.current_item {
                                    let label_span =
                                        current_item.kind.ident().map(|i|
                                                    i.span).unwrap_or(current_item.span);
                                    Some((label_span, current_item.span,
                                            current_item.kind.clone()))
                                } else { None };
                            self.report_error(span,
                                ResolutionError::GenericParamsFromOuterItem {
                                    outer_res: res,
                                    has_generic_params,
                                    def_kind,
                                    inner_item: item,
                                    current_self_ty: diag_metadata.and_then(|m|
                                                m.current_self_type.as_ref()).and_then(|ty|
                                            {
                                                self.tcx.sess.source_map().span_to_snippet(ty.span).ok()
                                            }),
                                });
                        }
                        return Res::Err;
                    }
                }
                Res::Def(DefKind::ConstParam, _) => {
                    for rib in ribs {
                        let (has_generic_params, def_kind) =
                            match rib.kind {
                                RibKind::Normal | RibKind::Block(..) |
                                    RibKind::FnOrCoroutine | RibKind::Module(..) |
                                    RibKind::MacroDefinition(..) | RibKind::InlineAsmSym |
                                    RibKind::AssocItem | RibKind::ForwardGenericParamBan(_) =>
                                    continue,
                                RibKind::ConstParamTy => {
                                    if !self.tcx.features().generic_const_parameter_types() {
                                        if let Some(span) = finalize {
                                            self.report_error(span,
                                                ResolutionError::ParamInTyOfConstParam {
                                                    name: rib_ident.name,
                                                });
                                        }
                                        return Res::Err;
                                    } else { continue; }
                                }
                                RibKind::ConstantItem(trivial, _) => {
                                    if let ConstantHasGenerics::No(cause) = trivial {
                                        if let Some(span) = finalize {
                                            let error =
                                                match cause {
                                                    NoConstantGenericsReason::IsEnumDiscriminant => {
                                                        ResolutionError::ParamInEnumDiscriminant {
                                                            name: rib_ident.name,
                                                            param_kind: ParamKindInEnumDiscriminant::Const,
                                                        }
                                                    }
                                                    NoConstantGenericsReason::NonTrivialConstArg => {
                                                        ResolutionError::ParamInNonTrivialAnonConst {
                                                            is_gca: self.tcx.features().generic_const_args(),
                                                            name: rib_ident.name,
                                                            param_kind: ParamKindInNonTrivialAnonConst::Const {
                                                                name: rib_ident.name,
                                                            },
                                                        }
                                                    }
                                                };
                                            self.report_error(span, error);
                                        }
                                        return Res::Err;
                                    }
                                    continue;
                                }
                                RibKind::Item(has_generic_params, def_kind) => {
                                    (has_generic_params, def_kind)
                                }
                            };
                        if let Some(span) = finalize {
                            let item =
                                if let Some(diag_metadata) = diag_metadata &&
                                        let Some(current_item) = diag_metadata.current_item {
                                    let label_span =
                                        current_item.kind.ident().map(|i|
                                                    i.span).unwrap_or(current_item.span);
                                    Some((label_span, current_item.span,
                                            current_item.kind.clone()))
                                } else { None };
                            self.report_error(span,
                                ResolutionError::GenericParamsFromOuterItem {
                                    outer_res: res,
                                    has_generic_params,
                                    def_kind,
                                    inner_item: item,
                                    current_self_ty: diag_metadata.and_then(|m|
                                                m.current_self_type.as_ref()).and_then(|ty|
                                            {
                                                self.tcx.sess.source_map().span_to_snippet(ty.span).ok()
                                            }),
                                });
                        }
                        return Res::Err;
                    }
                }
                _ => {}
            }
            res
        }
    }
}#[instrument(level = "debug", skip(self, all_ribs))]
1399    fn validate_res_from_ribs(
1400        &mut self,
1401        rib_index: usize,
1402        rib_ident: Ident,
1403        res: Res,
1404        finalize: Option<Span>,
1405        original_rib_ident_def: Ident,
1406        all_ribs: &[Rib<'ra>],
1407        diag_metadata: Option<&DiagMetadata<'_>>,
1408    ) -> Res {
1409        debug!("validate_res_from_ribs({:?})", res);
1410        let ribs = &all_ribs[rib_index + 1..];
1411
1412        // An invalid forward use of a generic parameter from a previous default
1413        // or in a const param ty.
1414        if let RibKind::ForwardGenericParamBan(reason) = all_ribs[rib_index].kind {
1415            if let Some(span) = finalize {
1416                let res_error = if rib_ident.name == kw::SelfUpper {
1417                    ResolutionError::ForwardDeclaredSelf(reason)
1418                } else {
1419                    ResolutionError::ForwardDeclaredGenericParam(rib_ident.name, reason)
1420                };
1421                self.report_error(span, res_error);
1422            }
1423            assert_eq!(res, Res::Err);
1424            return Res::Err;
1425        }
1426
1427        match res {
1428            Res::Local(_) => {
1429                use ResolutionError::*;
1430                let mut res_err = None;
1431
1432                for rib in ribs {
1433                    match rib.kind {
1434                        RibKind::Normal
1435                        | RibKind::Block(..)
1436                        | RibKind::FnOrCoroutine
1437                        | RibKind::Module(..)
1438                        | RibKind::MacroDefinition(..)
1439                        | RibKind::ForwardGenericParamBan(_) => {
1440                            // Nothing to do. Continue.
1441                        }
1442                        RibKind::Item(..) | RibKind::AssocItem => {
1443                            // This was an attempt to access an upvar inside a
1444                            // named function item. This is not allowed, so we
1445                            // report an error.
1446                            if let Some(span) = finalize {
1447                                // We don't immediately trigger a resolve error, because
1448                                // we want certain other resolution errors (namely those
1449                                // emitted for `ConstantItemRibKind` below) to take
1450                                // precedence.
1451                                res_err = Some((span, CannotCaptureDynamicEnvironmentInFnItem));
1452                            }
1453                        }
1454                        RibKind::ConstantItem(_, item) => {
1455                            // Still doesn't deal with upvars
1456                            if let Some(span) = finalize {
1457                                let (span, resolution_error) = match item {
1458                                    None if rib_ident.name == kw::SelfLower => {
1459                                        (span, LowercaseSelf)
1460                                    }
1461                                    None => {
1462                                        // If we have a `let name = expr;`, we have the span for
1463                                        // `name` and use that to see if it is followed by a type
1464                                        // specifier. If not, then we know we need to suggest
1465                                        // `const name: Ty = expr;`. This is a heuristic, it will
1466                                        // break down in the presence of macros.
1467                                        let sm = self.tcx.sess.source_map();
1468                                        let type_span = match sm
1469                                            .span_followed_by(original_rib_ident_def.span, ":")
1470                                        {
1471                                            None => {
1472                                                Some(original_rib_ident_def.span.shrink_to_hi())
1473                                            }
1474                                            Some(_) => None,
1475                                        };
1476                                        (
1477                                            rib_ident.span,
1478                                            AttemptToUseNonConstantValueInConstant {
1479                                                ident: original_rib_ident_def,
1480                                                suggestion: "const",
1481                                                current: "let",
1482                                                type_span,
1483                                            },
1484                                        )
1485                                    }
1486                                    Some((ident, kind)) => (
1487                                        span,
1488                                        AttemptToUseNonConstantValueInConstant {
1489                                            ident,
1490                                            suggestion: "let",
1491                                            current: kind.as_str(),
1492                                            type_span: None,
1493                                        },
1494                                    ),
1495                                };
1496                                self.report_error(span, resolution_error);
1497                            }
1498                            return Res::Err;
1499                        }
1500                        RibKind::ConstParamTy => {
1501                            if let Some(span) = finalize {
1502                                self.report_error(
1503                                    span,
1504                                    ParamInTyOfConstParam { name: rib_ident.name },
1505                                );
1506                            }
1507                            return Res::Err;
1508                        }
1509                        RibKind::InlineAsmSym => {
1510                            if let Some(span) = finalize {
1511                                self.report_error(span, InvalidAsmSym);
1512                            }
1513                            return Res::Err;
1514                        }
1515                    }
1516                }
1517                if let Some((span, res_err)) = res_err {
1518                    self.report_error(span, res_err);
1519                    return Res::Err;
1520                }
1521            }
1522            Res::Def(DefKind::TyParam, _) | Res::SelfTyParam { .. } | Res::SelfTyAlias { .. } => {
1523                for rib in ribs {
1524                    let (has_generic_params, def_kind) = match rib.kind {
1525                        RibKind::Normal
1526                        | RibKind::Block(..)
1527                        | RibKind::FnOrCoroutine
1528                        | RibKind::Module(..)
1529                        | RibKind::MacroDefinition(..)
1530                        | RibKind::InlineAsmSym
1531                        | RibKind::AssocItem
1532                        | RibKind::ForwardGenericParamBan(_) => {
1533                            // Nothing to do. Continue.
1534                            continue;
1535                        }
1536
1537                        RibKind::ConstParamTy => {
1538                            if !self.tcx.features().generic_const_parameter_types() {
1539                                if let Some(span) = finalize {
1540                                    self.report_error(
1541                                        span,
1542                                        ResolutionError::ParamInTyOfConstParam {
1543                                            name: rib_ident.name,
1544                                        },
1545                                    );
1546                                }
1547                                return Res::Err;
1548                            } else {
1549                                continue;
1550                            }
1551                        }
1552
1553                        RibKind::ConstantItem(trivial, _) => {
1554                            if let ConstantHasGenerics::No(cause) = trivial
1555                                && !matches!(res, Res::SelfTyAlias { .. })
1556                            {
1557                                if let Some(span) = finalize {
1558                                    let error = match cause {
1559                                        NoConstantGenericsReason::IsEnumDiscriminant => {
1560                                            ResolutionError::ParamInEnumDiscriminant {
1561                                                name: rib_ident.name,
1562                                                param_kind: ParamKindInEnumDiscriminant::Type,
1563                                            }
1564                                        }
1565                                        NoConstantGenericsReason::NonTrivialConstArg => {
1566                                            ResolutionError::ParamInNonTrivialAnonConst {
1567                                                is_gca: self.tcx.features().generic_const_args(),
1568                                                name: rib_ident.name,
1569                                                param_kind: ParamKindInNonTrivialAnonConst::Type,
1570                                            }
1571                                        }
1572                                    };
1573                                    let _: ErrorGuaranteed = self.report_error(span, error);
1574                                }
1575
1576                                return Res::Err;
1577                            }
1578
1579                            continue;
1580                        }
1581
1582                        // This was an attempt to use a type parameter outside its scope.
1583                        RibKind::Item(has_generic_params, def_kind) => {
1584                            (has_generic_params, def_kind)
1585                        }
1586                    };
1587
1588                    if let Some(span) = finalize {
1589                        let item = if let Some(diag_metadata) = diag_metadata
1590                            && let Some(current_item) = diag_metadata.current_item
1591                        {
1592                            let label_span = current_item
1593                                .kind
1594                                .ident()
1595                                .map(|i| i.span)
1596                                .unwrap_or(current_item.span);
1597                            Some((label_span, current_item.span, current_item.kind.clone()))
1598                        } else {
1599                            None
1600                        };
1601                        self.report_error(
1602                            span,
1603                            ResolutionError::GenericParamsFromOuterItem {
1604                                outer_res: res,
1605                                has_generic_params,
1606                                def_kind,
1607                                inner_item: item,
1608                                current_self_ty: diag_metadata
1609                                    .and_then(|m| m.current_self_type.as_ref())
1610                                    .and_then(|ty| {
1611                                        self.tcx.sess.source_map().span_to_snippet(ty.span).ok()
1612                                    }),
1613                            },
1614                        );
1615                    }
1616                    return Res::Err;
1617                }
1618            }
1619            Res::Def(DefKind::ConstParam, _) => {
1620                for rib in ribs {
1621                    let (has_generic_params, def_kind) = match rib.kind {
1622                        RibKind::Normal
1623                        | RibKind::Block(..)
1624                        | RibKind::FnOrCoroutine
1625                        | RibKind::Module(..)
1626                        | RibKind::MacroDefinition(..)
1627                        | RibKind::InlineAsmSym
1628                        | RibKind::AssocItem
1629                        | RibKind::ForwardGenericParamBan(_) => continue,
1630
1631                        RibKind::ConstParamTy => {
1632                            if !self.tcx.features().generic_const_parameter_types() {
1633                                if let Some(span) = finalize {
1634                                    self.report_error(
1635                                        span,
1636                                        ResolutionError::ParamInTyOfConstParam {
1637                                            name: rib_ident.name,
1638                                        },
1639                                    );
1640                                }
1641                                return Res::Err;
1642                            } else {
1643                                continue;
1644                            }
1645                        }
1646
1647                        RibKind::ConstantItem(trivial, _) => {
1648                            if let ConstantHasGenerics::No(cause) = trivial {
1649                                if let Some(span) = finalize {
1650                                    let error = match cause {
1651                                        NoConstantGenericsReason::IsEnumDiscriminant => {
1652                                            ResolutionError::ParamInEnumDiscriminant {
1653                                                name: rib_ident.name,
1654                                                param_kind: ParamKindInEnumDiscriminant::Const,
1655                                            }
1656                                        }
1657                                        NoConstantGenericsReason::NonTrivialConstArg => {
1658                                            ResolutionError::ParamInNonTrivialAnonConst {
1659                                                is_gca: self.tcx.features().generic_const_args(),
1660                                                name: rib_ident.name,
1661                                                param_kind: ParamKindInNonTrivialAnonConst::Const {
1662                                                    name: rib_ident.name,
1663                                                },
1664                                            }
1665                                        }
1666                                    };
1667                                    self.report_error(span, error);
1668                                }
1669
1670                                return Res::Err;
1671                            }
1672
1673                            continue;
1674                        }
1675
1676                        RibKind::Item(has_generic_params, def_kind) => {
1677                            (has_generic_params, def_kind)
1678                        }
1679                    };
1680
1681                    // This was an attempt to use a const parameter outside its scope.
1682                    if let Some(span) = finalize {
1683                        let item = if let Some(diag_metadata) = diag_metadata
1684                            && let Some(current_item) = diag_metadata.current_item
1685                        {
1686                            let label_span = current_item
1687                                .kind
1688                                .ident()
1689                                .map(|i| i.span)
1690                                .unwrap_or(current_item.span);
1691                            Some((label_span, current_item.span, current_item.kind.clone()))
1692                        } else {
1693                            None
1694                        };
1695                        self.report_error(
1696                            span,
1697                            ResolutionError::GenericParamsFromOuterItem {
1698                                outer_res: res,
1699                                has_generic_params,
1700                                def_kind,
1701                                inner_item: item,
1702                                current_self_ty: diag_metadata
1703                                    .and_then(|m| m.current_self_type.as_ref())
1704                                    .and_then(|ty| {
1705                                        self.tcx.sess.source_map().span_to_snippet(ty.span).ok()
1706                                    }),
1707                            },
1708                        );
1709                    }
1710                    return Res::Err;
1711                }
1712            }
1713            _ => {}
1714        }
1715
1716        res
1717    }
1718
1719    #[allow(clippy :: suspicious_else_formatting)]
{
    let __tracing_attr_span;
    let __tracing_attr_guard;
    if ::tracing::Level::DEBUG <= ::tracing::level_filters::STATIC_MAX_LEVEL
                &&
                ::tracing::Level::DEBUG <=
                    ::tracing::level_filters::LevelFilter::current() ||
            { false } {
        __tracing_attr_span =
            {
                use ::tracing::__macro_support::Callsite as _;
                static __CALLSITE: ::tracing::callsite::DefaultCallsite =
                    {
                        static META: ::tracing::Metadata<'static> =
                            {
                                ::tracing_core::metadata::Metadata::new("maybe_resolve_path",
                                    "rustc_resolve::ident", ::tracing::Level::DEBUG,
                                    ::tracing_core::__macro_support::Option::Some("compiler/rustc_resolve/src/ident.rs"),
                                    ::tracing_core::__macro_support::Option::Some(1719u32),
                                    ::tracing_core::__macro_support::Option::Some("rustc_resolve::ident"),
                                    ::tracing_core::field::FieldSet::new(&["path", "opt_ns",
                                                    "parent_scope", "ignore_import"],
                                        ::tracing_core::callsite::Identifier(&__CALLSITE)),
                                    ::tracing::metadata::Kind::SPAN)
                            };
                        ::tracing::callsite::DefaultCallsite::new(&META)
                    };
                let mut interest = ::tracing::subscriber::Interest::never();
                if ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::STATIC_MAX_LEVEL &&
                                ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::LevelFilter::current() &&
                            { interest = __CALLSITE.interest(); !interest.is_never() }
                        &&
                        ::tracing::__macro_support::__is_enabled(__CALLSITE.metadata(),
                            interest) {
                    let meta = __CALLSITE.metadata();
                    ::tracing::Span::new(meta,
                        &{
                                #[allow(unused_imports)]
                                use ::tracing::field::{debug, display, Value};
                                let mut iter = meta.fields().iter();
                                meta.fields().value_set(&[(&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&path)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&opt_ns)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&parent_scope)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ignore_import)
                                                            as &dyn Value))])
                            })
                } else {
                    let span =
                        ::tracing::__macro_support::__disabled_span(__CALLSITE.metadata());
                    {};
                    span
                }
            };
        __tracing_attr_guard = __tracing_attr_span.enter();
    }

    #[warn(clippy :: suspicious_else_formatting)]
    {

        #[allow(unknown_lints, unreachable_code, clippy ::
        diverging_sub_expression, clippy :: empty_loop, clippy ::
        let_unit_value, clippy :: let_with_type_underscore, clippy ::
        needless_return, clippy :: unreachable)]
        if false {
            let __tracing_attr_fake_return: PathResult<'ra> = loop {};
            return __tracing_attr_fake_return;
        }
        {
            self.resolve_path_with_ribs(path, opt_ns, parent_scope, None,
                None, None, None, ignore_import, None)
        }
    }
}#[instrument(level = "debug", skip(self))]
1720    pub(crate) fn maybe_resolve_path<'r>(
1721        self: CmResolver<'r, 'ra, 'tcx>,
1722        path: &[Segment],
1723        opt_ns: Option<Namespace>, // `None` indicates a module path in import
1724        parent_scope: &ParentScope<'ra>,
1725        ignore_import: Option<Import<'ra>>,
1726    ) -> PathResult<'ra> {
1727        self.resolve_path_with_ribs(
1728            path,
1729            opt_ns,
1730            parent_scope,
1731            None,
1732            None,
1733            None,
1734            None,
1735            ignore_import,
1736            None,
1737        )
1738    }
1739    #[allow(clippy :: suspicious_else_formatting)]
{
    let __tracing_attr_span;
    let __tracing_attr_guard;
    if ::tracing::Level::DEBUG <= ::tracing::level_filters::STATIC_MAX_LEVEL
                &&
                ::tracing::Level::DEBUG <=
                    ::tracing::level_filters::LevelFilter::current() ||
            { false } {
        __tracing_attr_span =
            {
                use ::tracing::__macro_support::Callsite as _;
                static __CALLSITE: ::tracing::callsite::DefaultCallsite =
                    {
                        static META: ::tracing::Metadata<'static> =
                            {
                                ::tracing_core::metadata::Metadata::new("resolve_path",
                                    "rustc_resolve::ident", ::tracing::Level::DEBUG,
                                    ::tracing_core::__macro_support::Option::Some("compiler/rustc_resolve/src/ident.rs"),
                                    ::tracing_core::__macro_support::Option::Some(1739u32),
                                    ::tracing_core::__macro_support::Option::Some("rustc_resolve::ident"),
                                    ::tracing_core::field::FieldSet::new(&["path", "opt_ns",
                                                    "parent_scope", "finalize", "ignore_decl", "ignore_import"],
                                        ::tracing_core::callsite::Identifier(&__CALLSITE)),
                                    ::tracing::metadata::Kind::SPAN)
                            };
                        ::tracing::callsite::DefaultCallsite::new(&META)
                    };
                let mut interest = ::tracing::subscriber::Interest::never();
                if ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::STATIC_MAX_LEVEL &&
                                ::tracing::Level::DEBUG <=
                                    ::tracing::level_filters::LevelFilter::current() &&
                            { interest = __CALLSITE.interest(); !interest.is_never() }
                        &&
                        ::tracing::__macro_support::__is_enabled(__CALLSITE.metadata(),
                            interest) {
                    let meta = __CALLSITE.metadata();
                    ::tracing::Span::new(meta,
                        &{
                                #[allow(unused_imports)]
                                use ::tracing::field::{debug, display, Value};
                                let mut iter = meta.fields().iter();
                                meta.fields().value_set(&[(&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&path)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&opt_ns)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&parent_scope)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&finalize)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ignore_decl)
                                                            as &dyn Value)),
                                                (&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                                    ::tracing::__macro_support::Option::Some(&::tracing::field::debug(&ignore_import)
                                                            as &dyn Value))])
                            })
                } else {
                    let span =
                        ::tracing::__macro_support::__disabled_span(__CALLSITE.metadata());
                    {};
                    span
                }
            };
        __tracing_attr_guard = __tracing_attr_span.enter();
    }

    #[warn(clippy :: suspicious_else_formatting)]
    {

        #[allow(unknown_lints, unreachable_code, clippy ::
        diverging_sub_expression, clippy :: empty_loop, clippy ::
        let_unit_value, clippy :: let_with_type_underscore, clippy ::
        needless_return, clippy :: unreachable)]
        if false {
            let __tracing_attr_fake_return: PathResult<'ra> = loop {};
            return __tracing_attr_fake_return;
        }
        {
            self.resolve_path_with_ribs(path, opt_ns, parent_scope, None,
                finalize, None, ignore_decl, ignore_import, None)
        }
    }
}#[instrument(level = "debug", skip(self))]
1740    pub(crate) fn resolve_path<'r>(
1741        self: CmResolver<'r, 'ra, 'tcx>,
1742        path: &[Segment],
1743        opt_ns: Option<Namespace>, // `None` indicates a module path in import
1744        parent_scope: &ParentScope<'ra>,
1745        finalize: Option<Finalize>,
1746        ignore_decl: Option<Decl<'ra>>,
1747        ignore_import: Option<Import<'ra>>,
1748    ) -> PathResult<'ra> {
1749        self.resolve_path_with_ribs(
1750            path,
1751            opt_ns,
1752            parent_scope,
1753            None,
1754            finalize,
1755            None,
1756            ignore_decl,
1757            ignore_import,
1758            None,
1759        )
1760    }
1761
1762    pub(crate) fn resolve_path_with_ribs<'r>(
1763        mut self: CmResolver<'r, 'ra, 'tcx>,
1764        path: &[Segment],
1765        opt_ns: Option<Namespace>, // `None` indicates a module path in import
1766        parent_scope: &ParentScope<'ra>,
1767        source: Option<PathSource<'_, '_, '_>>,
1768        finalize: Option<Finalize>,
1769        ribs: Option<&PerNS<Vec<Rib<'ra>>>>,
1770        ignore_decl: Option<Decl<'ra>>,
1771        ignore_import: Option<Import<'ra>>,
1772        diag_metadata: Option<&DiagMetadata<'_>>,
1773    ) -> PathResult<'ra> {
1774        let mut module = None;
1775        let mut module_had_parse_errors = !self.mods_with_parse_errors.is_empty()
1776            && self.mods_with_parse_errors.contains(&parent_scope.module.nearest_parent_mod());
1777        let mut allow_super = true;
1778        let mut second_binding = None;
1779
1780        // We'll provide more context to the privacy errors later, up to `len`.
1781        let privacy_errors_len = self.privacy_errors.len();
1782        fn record_segment_res<'r, 'ra, 'tcx>(
1783            mut this: CmResolver<'r, 'ra, 'tcx>,
1784            finalize: Option<Finalize>,
1785            res: Res,
1786            id: Option<NodeId>,
1787        ) {
1788            if finalize.is_some()
1789                && let Some(id) = id
1790                && !this.partial_res_map.contains_key(&id)
1791            {
1792                if !(id != ast::DUMMY_NODE_ID) {
    {
        ::core::panicking::panic_fmt(format_args!("Trying to resolve dummy id"));
    }
};assert!(id != ast::DUMMY_NODE_ID, "Trying to resolve dummy id");
1793                this.get_mut().record_partial_res(id, PartialRes::new(res));
1794            }
1795        }
1796
1797        for (segment_idx, &Segment { ident, id, .. }) in path.iter().enumerate() {
1798            {
    use ::tracing::__macro_support::Callsite as _;
    static __CALLSITE: ::tracing::callsite::DefaultCallsite =
        {
            static META: ::tracing::Metadata<'static> =
                {
                    ::tracing_core::metadata::Metadata::new("event compiler/rustc_resolve/src/ident.rs:1798",
                        "rustc_resolve::ident", ::tracing::Level::DEBUG,
                        ::tracing_core::__macro_support::Option::Some("compiler/rustc_resolve/src/ident.rs"),
                        ::tracing_core::__macro_support::Option::Some(1798u32),
                        ::tracing_core::__macro_support::Option::Some("rustc_resolve::ident"),
                        ::tracing_core::field::FieldSet::new(&["message"],
                            ::tracing_core::callsite::Identifier(&__CALLSITE)),
                        ::tracing::metadata::Kind::EVENT)
                };
            ::tracing::callsite::DefaultCallsite::new(&META)
        };
    let enabled =
        ::tracing::Level::DEBUG <= ::tracing::level_filters::STATIC_MAX_LEVEL
                &&
                ::tracing::Level::DEBUG <=
                    ::tracing::level_filters::LevelFilter::current() &&
            {
                let interest = __CALLSITE.interest();
                !interest.is_never() &&
                    ::tracing::__macro_support::__is_enabled(__CALLSITE.metadata(),
                        interest)
            };
    if enabled {
        (|value_set: ::tracing::field::ValueSet|
                    {
                        let meta = __CALLSITE.metadata();
                        ::tracing::Event::dispatch(meta, &value_set);
                        ;
                    })({
                #[allow(unused_imports)]
                use ::tracing::field::{debug, display, Value};
                let mut iter = __CALLSITE.metadata().fields().iter();
                __CALLSITE.metadata().fields().value_set(&[(&::tracing::__macro_support::Iterator::next(&mut iter).expect("FieldSet corrupted (this is a bug)"),
                                    ::tracing::__macro_support::Option::Some(&format_args!("resolve_path ident {0} {1:?} {2:?}",
                                                    segment_idx, ident, id) as &dyn Value))])
            });
    } else { ; }
};debug!("resolve_path ident {} {:?} {:?}", segment_idx, ident, id);
1799
1800            let is_last = segment_idx + 1 == path.len();
1801            let ns = if is_last { opt_ns.unwrap_or(TypeNS) } else { TypeNS };
1802            let name = ident.name;
1803
1804            allow_super &= ns == TypeNS && (name == kw::SelfLower || name == kw::Super);
1805
1806            if ns == TypeNS {
1807                if allow_super && name == kw::Super {
1808                    let parent = if segment_idx == 0 {
1809                        self.resolve_super_in_module(ident, None, parent_scope)
1810                    } else if let Some(ModuleOrUniformRoot::Module(module)) = module {
1811                        self.resolve_super_in_module(ident, Some(module), parent_scope)
1812                    } else {
1813                        None
1814                    };
1815                    if let Some(parent) = parent {
1816                        module = Some(ModuleOrUniformRoot::Module(parent));
1817                        continue;
1818                    }
1819                    return PathResult::failed(
1820                        ident,
1821                        false,
1822                        finalize.is_some(),
1823                        module_had_parse_errors,
1824                        module,
1825                        || {
1826                            (
1827                                "too many leading `super` keywords".to_string(),
1828                                "there are too many leading `super` keywords".to_string(),
1829                                None,
1830                                None,
1831                            )
1832                        },
1833                    );
1834                }
1835                if segment_idx == 0 {
1836                    if name == kw::SelfLower {
1837                        let mut ctxt = ident.span.ctxt().normalize_to_macros_2_0();
1838                        let self_mod = self.resolve_self(&mut ctxt, parent_scope.module);
1839                        if let Some(res) = self_mod.res() {
1840                            record_segment_res(self.reborrow(), finalize, res, id);
1841                        }
1842                        module = Some(ModuleOrUniformRoot::Module(self_mod));
1843                        continue;
1844                    }
1845                    if name == kw::PathRoot && ident.span.at_least_rust_2018() {
1846                        module = Some(ModuleOrUniformRoot::ExternPrelude);
1847                        continue;
1848                    }
1849                    if name == kw::PathRoot
1850                        && ident.span.is_rust_2015()
1851                        && self.tcx.sess.at_least_rust_2018()
1852                    {
1853                        // `::a::b` from 2015 macro on 2018 global edition
1854                        let crate_root = self.resolve_crate_root(ident);
1855                        module = Some(ModuleOrUniformRoot::ModuleAndExternPrelude(crate_root));
1856                        continue;
1857                    }
1858                    if name == kw::PathRoot || name == kw::Crate || name == kw::DollarCrate {
1859                        // `::a::b`, `crate::a::b` or `$crate::a::b`
1860                        let crate_root = self.resolve_crate_root(ident);
1861                        if let Some(res) = crate_root.res() {
1862                            record_segment_res(self.reborrow(), finalize, res, id);
1863                        }
1864                        module = Some(ModuleOrUniformRoot::Module(crate_root));
1865                        continue;
1866                    }
1867                }
1868            }
1869
1870            let allow_trailing_self = is_last && name == kw::SelfLower;
1871
1872            // Report special messages for path segment keywords in wrong positions.
1873            if ident.is_path_segment_keyword() && segment_idx != 0 && !allow_trailing_self {
1874                return PathResult::failed(
1875                    ident,
1876                    false,
1877                    finalize.is_some(),
1878                    module_had_parse_errors,
1879                    module,
1880                    || {
1881                        let name_str = if name == kw::PathRoot {
1882                            "the crate root".to_string()
1883                        } else {
1884                            ::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("`{0}`", name))
    })format!("`{name}`")
1885                        };
1886                        let (message, label) = if segment_idx == 1
1887                            && path[0].ident.name == kw::PathRoot
1888                        {
1889                            (
1890                                ::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("global paths cannot start with {0}",
                name_str))
    })format!("global paths cannot start with {name_str}"),
1891                                "cannot start with this".to_string(),
1892                            )
1893                        } else if name == kw::SelfLower {
1894                            (
1895                                ::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("`self` in paths can only be used in start position or last position"))
    })format!(
1896                                    "`self` in paths can only be used in start position or last position"
1897                                ),
1898                                "can only be used in path start position or last position"
1899                                    .to_string(),
1900                            )
1901                        } else {
1902                            (
1903                                ::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("{0} in paths can only be used in start position",
                name_str))
    })format!("{name_str} in paths can only be used in start position"),
1904                                "can only be used in path start position".to_string(),
1905                            )
1906                        };
1907                        (message, label, None, None)
1908                    },
1909                );
1910            }
1911
1912            let binding = if let Some(module) = module {
1913                self.reborrow().resolve_ident_in_module(
1914                    module,
1915                    ident,
1916                    ns,
1917                    parent_scope,
1918                    finalize,
1919                    ignore_decl,
1920                    ignore_import,
1921                )
1922            } else if let Some(ribs) = ribs
1923                && let Some(TypeNS | ValueNS) = opt_ns
1924            {
1925                if !ignore_import.is_none() {
    ::core::panicking::panic("assertion failed: ignore_import.is_none()")
};assert!(ignore_import.is_none());
1926                match self.get_mut().resolve_ident_in_lexical_scope(
1927                    ident,
1928                    ns,
1929                    parent_scope,
1930                    finalize,
1931                    &ribs[ns],
1932                    ignore_decl,
1933                    diag_metadata,
1934                ) {
1935                    // we found a locally-imported or available item/module
1936                    Some(LateDecl::Decl(binding)) => Ok(binding),
1937                    // we found a local variable or type param
1938                    Some(LateDecl::RibDef(res)) => {
1939                        record_segment_res(self.reborrow(), finalize, res, id);
1940                        return PathResult::NonModule(PartialRes::with_unresolved_segments(
1941                            res,
1942                            path.len() - 1,
1943                        ));
1944                    }
1945                    _ => Err(Determinacy::determined(finalize.is_some())),
1946                }
1947            } else {
1948                self.reborrow().resolve_ident_in_scope_set(
1949                    ident,
1950                    ScopeSet::All(ns),
1951                    parent_scope,
1952                    finalize,
1953                    ignore_decl,
1954                    ignore_import,
1955                )
1956            };
1957
1958            match binding {
1959                Ok(binding) => {
1960                    if segment_idx == 1 {
1961                        second_binding = Some(binding);
1962                    }
1963                    let res = binding.res();
1964
1965                    // Mark every privacy error in this path with the res to the last element. This allows us
1966                    // to detect the item the user cares about and either find an alternative import, or tell
1967                    // the user it is not accessible.
1968                    if finalize.is_some() {
1969                        for error in &mut self.get_mut().privacy_errors[privacy_errors_len..] {
1970                            error.outermost_res = Some((res, ident));
1971                            error.source = match source {
1972                                Some(PathSource::Struct(Some(expr)))
1973                                | Some(PathSource::Expr(Some(expr))) => Some(expr.clone()),
1974                                _ => None,
1975                            };
1976                        }
1977                    }
1978
1979                    let maybe_assoc = opt_ns != Some(MacroNS) && PathSource::Type.is_expected(res);
1980                    if let Res::OpenMod(sym) = binding.res() {
1981                        module = Some(ModuleOrUniformRoot::OpenModule(sym));
1982                        record_segment_res(self.reborrow(), finalize, res, id);
1983                    } else if let Some(def_id) = binding.res().module_like_def_id() {
1984                        if self.mods_with_parse_errors.contains(&def_id) {
1985                            module_had_parse_errors = true;
1986                        }
1987                        module = Some(ModuleOrUniformRoot::Module(self.expect_module(def_id)));
1988                        record_segment_res(self.reborrow(), finalize, res, id);
1989                    } else if res == Res::ToolMod && !is_last && opt_ns.is_some() {
1990                        if binding.is_import() {
1991                            self.dcx().emit_err(errors::ToolModuleImported {
1992                                span: ident.span,
1993                                import: binding.span,
1994                            });
1995                        }
1996                        let res = Res::NonMacroAttr(NonMacroAttrKind::Tool);
1997                        return PathResult::NonModule(PartialRes::new(res));
1998                    } else if res == Res::Err {
1999                        return PathResult::NonModule(PartialRes::new(Res::Err));
2000                    } else if opt_ns.is_some() && (is_last || maybe_assoc) {
2001                        if let Some(finalize) = finalize {
2002                            self.get_mut().lint_if_path_starts_with_module(
2003                                finalize,
2004                                path,
2005                                second_binding,
2006                            );
2007                        }
2008                        record_segment_res(self.reborrow(), finalize, res, id);
2009                        return PathResult::NonModule(PartialRes::with_unresolved_segments(
2010                            res,
2011                            path.len() - segment_idx - 1,
2012                        ));
2013                    } else {
2014                        return PathResult::failed(
2015                            ident,
2016                            is_last,
2017                            finalize.is_some(),
2018                            module_had_parse_errors,
2019                            module,
2020                            || {
2021                                let import_inherent_item_error_flag =
2022                                    self.tcx.features().import_trait_associated_functions()
2023                                        && #[allow(non_exhaustive_omitted_patterns)] match res {
    Res::Def(DefKind::Struct | DefKind::Enum | DefKind::Union |
        DefKind::ForeignTy, _) => true,
    _ => false,
}matches!(
2024                                            res,
2025                                            Res::Def(
2026                                                DefKind::Struct
2027                                                    | DefKind::Enum
2028                                                    | DefKind::Union
2029                                                    | DefKind::ForeignTy,
2030                                                _
2031                                            )
2032                                        );
2033                                // Show a different error message for items that can have associated items.
2034                                let label = ::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("`{3}` is {0} {1}, not a module{2}",
                res.article(), res.descr(),
                if import_inherent_item_error_flag {
                    " or a trait"
                } else { "" }, ident))
    })format!(
2035                                    "`{ident}` is {} {}, not a module{}",
2036                                    res.article(),
2037                                    res.descr(),
2038                                    if import_inherent_item_error_flag {
2039                                        " or a trait"
2040                                    } else {
2041                                        ""
2042                                    }
2043                                );
2044                                let scope = match &path[..segment_idx] {
2045                                    [.., prev] => {
2046                                        if prev.ident.name == kw::PathRoot {
2047                                            ::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("the crate root"))
    })format!("the crate root")
2048                                        } else {
2049                                            ::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("`{0}`", prev.ident))
    })format!("`{}`", prev.ident)
2050                                        }
2051                                    }
2052                                    _ => ::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("this scope"))
    })format!("this scope"),
2053                                };
2054                                // FIXME: reword, as the reason we expected a module is because of
2055                                // the following path segment.
2056                                let message = ::alloc::__export::must_use({
        ::alloc::fmt::format(format_args!("cannot find module `{0}` in {1}",
                ident, scope))
    })format!("cannot find module `{ident}` in {scope}");
2057                                let note = if import_inherent_item_error_flag {
2058                                    Some(
2059                                        "cannot import inherent associated items, only trait associated items".to_string(),
2060                                    )
2061                                } else {
2062                                    None
2063                                };
2064                                (message, label, None, note)
2065                            },
2066                        );
2067                    }
2068                }
2069                Err(Undetermined) if finalize.is_none() => return PathResult::Indeterminate,
2070                Err(Determined | Undetermined) => {
2071                    if let Some(ModuleOrUniformRoot::Module(module)) = module
2072                        && opt_ns.is_some()
2073                        && !module.is_normal()
2074                    {
2075                        return PathResult::NonModule(PartialRes::with_unresolved_segments(
2076                            module.res().unwrap(),
2077                            path.len() - segment_idx,
2078                        ));
2079                    }
2080
2081                    let mut this = self.reborrow();
2082                    return PathResult::failed(
2083                        ident,
2084                        is_last,
2085                        finalize.is_some(),
2086                        module_had_parse_errors,
2087                        module,
2088                        || {
2089                            let (message, label, suggestion) =
2090                                this.get_mut().report_path_resolution_error(
2091                                    path,
2092                                    opt_ns,
2093                                    parent_scope,
2094                                    ribs,
2095                                    ignore_decl,
2096                                    ignore_import,
2097                                    module,
2098                                    segment_idx,
2099                                    ident,
2100                                    diag_metadata,
2101                                );
2102                            (message, label, suggestion, None)
2103                        },
2104                    );
2105                }
2106            }
2107        }
2108
2109        if let Some(finalize) = finalize {
2110            self.get_mut().lint_if_path_starts_with_module(finalize, path, second_binding);
2111        }
2112
2113        PathResult::Module(match module {
2114            Some(module) => module,
2115            None if path.is_empty() => ModuleOrUniformRoot::CurrentScope,
2116            _ => ::rustc_middle::util::bug::bug_fmt(format_args!("resolve_path: non-empty path `{0:?}` has no module",
        path))bug!("resolve_path: non-empty path `{:?}` has no module", path),
2117        })
2118    }
2119}