1use std::cell::Cell;
5use std::mem;
6use std::sync::Arc;
7
8use rustc_ast::expand::StrippedCfgItem;
9use rustc_ast::{self as ast, Crate, NodeId, attr};
10use rustc_ast_pretty::pprust;
11use rustc_attr_data_structures::StabilityLevel;
12use rustc_data_structures::intern::Interned;
13use rustc_errors::{Applicability, DiagCtxtHandle, StashKey};
14use rustc_expand::base::{
15 Annotatable, DeriveResolution, Indeterminate, ResolverExpand, SyntaxExtension,
16 SyntaxExtensionKind,
17};
18use rustc_expand::compile_declarative_macro;
19use rustc_expand::expand::{
20 AstFragment, AstFragmentKind, Invocation, InvocationKind, SupportsMacroExpansion,
21};
22use rustc_hir::def::{self, DefKind, Namespace, NonMacroAttrKind};
23use rustc_hir::def_id::{CrateNum, DefId, LocalDefId};
24use rustc_middle::middle::stability;
25use rustc_middle::ty::{RegisteredTools, TyCtxt, Visibility};
26use rustc_session::lint::BuiltinLintDiag;
27use rustc_session::lint::builtin::{
28 LEGACY_DERIVE_HELPERS, OUT_OF_SCOPE_MACRO_CALLS, UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES,
29 UNUSED_MACRO_RULES, UNUSED_MACROS,
30};
31use rustc_session::parse::feature_err;
32use rustc_span::edit_distance::find_best_match_for_name;
33use rustc_span::edition::Edition;
34use rustc_span::hygiene::{self, AstPass, ExpnData, ExpnKind, LocalExpnId, MacroKind};
35use rustc_span::{DUMMY_SP, Ident, Span, Symbol, kw, sym};
36
37use crate::Namespace::*;
38use crate::errors::{
39 self, AddAsNonDerive, CannotDetermineMacroResolution, CannotFindIdentInThisScope,
40 MacroExpectedFound, RemoveSurroundingDerive,
41};
42use crate::imports::Import;
43use crate::{
44 BindingKey, DeriveData, Determinacy, Finalize, InvocationParent, MacroData, ModuleKind,
45 ModuleOrUniformRoot, NameBinding, NameBindingKind, ParentScope, PathResult, ResolutionError,
46 Resolver, ScopeSet, Segment, ToNameBinding, Used,
47};
48
49type Res = def::Res<NodeId>;
50
51#[derive(Debug)]
54pub(crate) struct MacroRulesBinding<'ra> {
55 pub(crate) binding: NameBinding<'ra>,
56 pub(crate) parent_macro_rules_scope: MacroRulesScopeRef<'ra>,
58 pub(crate) ident: Ident,
59}
60
61#[derive(Copy, Clone, Debug)]
67pub(crate) enum MacroRulesScope<'ra> {
68 Empty,
70 Binding(&'ra MacroRulesBinding<'ra>),
72 Invocation(LocalExpnId),
75}
76
77pub(crate) type MacroRulesScopeRef<'ra> = Interned<'ra, Cell<MacroRulesScope<'ra>>>;
84
85pub(crate) fn sub_namespace_match(
89 candidate: Option<MacroKind>,
90 requirement: Option<MacroKind>,
91) -> bool {
92 #[derive(PartialEq)]
93 enum SubNS {
94 Bang,
95 AttrLike,
96 }
97 let sub_ns = |kind| match kind {
98 MacroKind::Bang => SubNS::Bang,
99 MacroKind::Attr | MacroKind::Derive => SubNS::AttrLike,
100 };
101 let candidate = candidate.map(sub_ns);
102 let requirement = requirement.map(sub_ns);
103 candidate.is_none() || requirement.is_none() || candidate == requirement
105}
106
107fn fast_print_path(path: &ast::Path) -> Symbol {
111 if let [segment] = path.segments.as_slice() {
112 segment.ident.name
113 } else {
114 let mut path_str = String::with_capacity(64);
115 for (i, segment) in path.segments.iter().enumerate() {
116 if i != 0 {
117 path_str.push_str("::");
118 }
119 if segment.ident.name != kw::PathRoot {
120 path_str.push_str(segment.ident.as_str())
121 }
122 }
123 Symbol::intern(&path_str)
124 }
125}
126
127pub(crate) fn registered_tools(tcx: TyCtxt<'_>, (): ()) -> RegisteredTools {
128 let (_, pre_configured_attrs) = &*tcx.crate_for_resolver(()).borrow();
129 registered_tools_ast(tcx.dcx(), pre_configured_attrs)
130}
131
132pub fn registered_tools_ast(
133 dcx: DiagCtxtHandle<'_>,
134 pre_configured_attrs: &[ast::Attribute],
135) -> RegisteredTools {
136 let mut registered_tools = RegisteredTools::default();
137 for attr in attr::filter_by_name(pre_configured_attrs, sym::register_tool) {
138 for meta_item_inner in attr.meta_item_list().unwrap_or_default() {
139 match meta_item_inner.ident() {
140 Some(ident) => {
141 if let Some(old_ident) = registered_tools.replace(ident) {
142 dcx.emit_err(errors::ToolWasAlreadyRegistered {
143 span: ident.span,
144 tool: ident,
145 old_ident_span: old_ident.span,
146 });
147 }
148 }
149 None => {
150 dcx.emit_err(errors::ToolOnlyAcceptsIdentifiers {
151 span: meta_item_inner.span(),
152 tool: sym::register_tool,
153 });
154 }
155 }
156 }
157 }
158 let predefined_tools =
161 [sym::clippy, sym::rustfmt, sym::diagnostic, sym::miri, sym::rust_analyzer];
162 registered_tools.extend(predefined_tools.iter().cloned().map(Ident::with_dummy_span));
163 registered_tools
164}
165
166impl<'ra, 'tcx> ResolverExpand for Resolver<'ra, 'tcx> {
167 fn next_node_id(&mut self) -> NodeId {
168 self.next_node_id()
169 }
170
171 fn invocation_parent(&self, id: LocalExpnId) -> LocalDefId {
172 self.invocation_parents[&id].parent_def
173 }
174
175 fn resolve_dollar_crates(&mut self) {
176 hygiene::update_dollar_crate_names(|ctxt| {
177 let ident = Ident::new(kw::DollarCrate, DUMMY_SP.with_ctxt(ctxt));
178 match self.resolve_crate_root(ident).kind {
179 ModuleKind::Def(.., name) if let Some(name) = name => name,
180 _ => kw::Crate,
181 }
182 });
183 }
184
185 fn visit_ast_fragment_with_placeholders(
186 &mut self,
187 expansion: LocalExpnId,
188 fragment: &AstFragment,
189 ) {
190 let parent_scope = ParentScope { expansion, ..self.invocation_parent_scopes[&expansion] };
193 let output_macro_rules_scope = self.build_reduced_graph(fragment, parent_scope);
194 self.output_macro_rules_scopes.insert(expansion, output_macro_rules_scope);
195
196 parent_scope.module.unexpanded_invocations.borrow_mut().remove(&expansion);
197 if let Some(unexpanded_invocations) =
198 self.impl_unexpanded_invocations.get_mut(&self.invocation_parent(expansion))
199 {
200 unexpanded_invocations.remove(&expansion);
201 }
202 }
203
204 fn register_builtin_macro(&mut self, name: Symbol, ext: SyntaxExtensionKind) {
205 if self.builtin_macros.insert(name, ext).is_some() {
206 self.dcx().bug(format!("built-in macro `{name}` was already registered"));
207 }
208 }
209
210 fn expansion_for_ast_pass(
213 &mut self,
214 call_site: Span,
215 pass: AstPass,
216 features: &[Symbol],
217 parent_module_id: Option<NodeId>,
218 ) -> LocalExpnId {
219 let parent_module =
220 parent_module_id.map(|module_id| self.local_def_id(module_id).to_def_id());
221 let expn_id = LocalExpnId::fresh(
222 ExpnData::allow_unstable(
223 ExpnKind::AstPass(pass),
224 call_site,
225 self.tcx.sess.edition(),
226 features.into(),
227 None,
228 parent_module,
229 ),
230 self.create_stable_hashing_context(),
231 );
232
233 let parent_scope =
234 parent_module.map_or(self.empty_module, |def_id| self.expect_module(def_id));
235 self.ast_transform_scopes.insert(expn_id, parent_scope);
236
237 expn_id
238 }
239
240 fn resolve_imports(&mut self) {
241 self.resolve_imports()
242 }
243
244 fn resolve_macro_invocation(
245 &mut self,
246 invoc: &Invocation,
247 eager_expansion_root: LocalExpnId,
248 force: bool,
249 ) -> Result<Arc<SyntaxExtension>, Indeterminate> {
250 let invoc_id = invoc.expansion_data.id;
251 let parent_scope = match self.invocation_parent_scopes.get(&invoc_id) {
252 Some(parent_scope) => *parent_scope,
253 None => {
254 let parent_scope = *self
258 .invocation_parent_scopes
259 .get(&eager_expansion_root)
260 .expect("non-eager expansion without a parent scope");
261 self.invocation_parent_scopes.insert(invoc_id, parent_scope);
262 parent_scope
263 }
264 };
265
266 let (mut derives, mut inner_attr, mut deleg_impl) = (&[][..], false, None);
267 let (path, kind) = match invoc.kind {
268 InvocationKind::Attr { ref attr, derives: ref attr_derives, .. } => {
269 derives = self.arenas.alloc_ast_paths(attr_derives);
270 inner_attr = attr.style == ast::AttrStyle::Inner;
271 (&attr.get_normal_item().path, MacroKind::Attr)
272 }
273 InvocationKind::Bang { ref mac, .. } => (&mac.path, MacroKind::Bang),
274 InvocationKind::Derive { ref path, .. } => (path, MacroKind::Derive),
275 InvocationKind::GlobDelegation { ref item, .. } => {
276 let ast::AssocItemKind::DelegationMac(deleg) = &item.kind else { unreachable!() };
277 deleg_impl = Some(self.invocation_parent(invoc_id));
278 (&deleg.prefix, MacroKind::Bang)
280 }
281 };
282
283 let parent_scope = &ParentScope { derives, ..parent_scope };
285 let supports_macro_expansion = invoc.fragment_kind.supports_macro_expansion();
286 let node_id = invoc.expansion_data.lint_node_id;
287 let looks_like_invoc_in_mod_inert_attr = self
289 .invocation_parents
290 .get(&invoc_id)
291 .or_else(|| self.invocation_parents.get(&eager_expansion_root))
292 .filter(|&&InvocationParent { parent_def: mod_def_id, in_attr, .. }| {
293 in_attr
294 && invoc.fragment_kind == AstFragmentKind::Expr
295 && self.tcx.def_kind(mod_def_id) == DefKind::Mod
296 })
297 .map(|&InvocationParent { parent_def: mod_def_id, .. }| mod_def_id);
298 let sugg_span = match &invoc.kind {
299 InvocationKind::Attr { item: Annotatable::Item(item), .. }
300 if !item.span.from_expansion() =>
301 {
302 Some(item.span.shrink_to_lo())
303 }
304 _ => None,
305 };
306 let (ext, res) = self.smart_resolve_macro_path(
307 path,
308 kind,
309 supports_macro_expansion,
310 inner_attr,
311 parent_scope,
312 node_id,
313 force,
314 deleg_impl,
315 looks_like_invoc_in_mod_inert_attr,
316 sugg_span,
317 )?;
318
319 let span = invoc.span();
320 let def_id = if deleg_impl.is_some() { None } else { res.opt_def_id() };
321 invoc_id.set_expn_data(
322 ext.expn_data(
323 parent_scope.expansion,
324 span,
325 fast_print_path(path),
326 def_id,
327 def_id.map(|def_id| self.macro_def_scope(def_id).nearest_parent_mod()),
328 ),
329 self.create_stable_hashing_context(),
330 );
331
332 Ok(ext)
333 }
334
335 fn record_macro_rule_usage(&mut self, id: NodeId, rule_i: usize) {
336 if let Some(rules) = self.unused_macro_rules.get_mut(&id) {
337 rules.remove(rule_i);
338 }
339 }
340
341 fn check_unused_macros(&mut self) {
342 for (_, &(node_id, ident)) in self.unused_macros.iter() {
343 self.lint_buffer.buffer_lint(
344 UNUSED_MACROS,
345 node_id,
346 ident.span,
347 BuiltinLintDiag::UnusedMacroDefinition(ident.name),
348 );
349 self.unused_macro_rules.swap_remove(&node_id);
351 }
352
353 for (&node_id, unused_arms) in self.unused_macro_rules.iter() {
354 if unused_arms.is_empty() {
355 continue;
356 }
357 let def_id = self.local_def_id(node_id).to_def_id();
358 let m = &self.macro_map[&def_id];
359 let SyntaxExtensionKind::LegacyBang(ref ext) = m.ext.kind else {
360 continue;
361 };
362 for arm_i in unused_arms.iter() {
363 if let Some((ident, rule_span)) = ext.get_unused_rule(arm_i) {
364 self.lint_buffer.buffer_lint(
365 UNUSED_MACRO_RULES,
366 node_id,
367 rule_span,
368 BuiltinLintDiag::MacroRuleNeverUsed(arm_i, ident.name),
369 );
370 }
371 }
372 }
373 }
374
375 fn has_derive_copy(&self, expn_id: LocalExpnId) -> bool {
376 self.containers_deriving_copy.contains(&expn_id)
377 }
378
379 fn resolve_derives(
380 &mut self,
381 expn_id: LocalExpnId,
382 force: bool,
383 derive_paths: &dyn Fn() -> Vec<DeriveResolution>,
384 ) -> Result<(), Indeterminate> {
385 let mut derive_data = mem::take(&mut self.derive_data);
393 let entry = derive_data.entry(expn_id).or_insert_with(|| DeriveData {
394 resolutions: derive_paths(),
395 helper_attrs: Vec::new(),
396 has_derive_copy: false,
397 });
398 let parent_scope = self.invocation_parent_scopes[&expn_id];
399 for (i, resolution) in entry.resolutions.iter_mut().enumerate() {
400 if resolution.exts.is_none() {
401 resolution.exts = Some(
402 match self.resolve_macro_path(
403 &resolution.path,
404 Some(MacroKind::Derive),
405 &parent_scope,
406 true,
407 force,
408 None,
409 None,
410 ) {
411 Ok((Some(ext), _)) => {
412 if !ext.helper_attrs.is_empty() {
413 let last_seg = resolution.path.segments.last().unwrap();
414 let span = last_seg.ident.span.normalize_to_macros_2_0();
415 entry.helper_attrs.extend(
416 ext.helper_attrs
417 .iter()
418 .map(|name| (i, Ident::new(*name, span))),
419 );
420 }
421 entry.has_derive_copy |= ext.builtin_name == Some(sym::Copy);
422 ext
423 }
424 Ok(_) | Err(Determinacy::Determined) => self.dummy_ext(MacroKind::Derive),
425 Err(Determinacy::Undetermined) => {
426 assert!(self.derive_data.is_empty());
427 self.derive_data = derive_data;
428 return Err(Indeterminate);
429 }
430 },
431 );
432 }
433 }
434 entry.helper_attrs.sort_by_key(|(i, _)| *i);
436 let helper_attrs = entry
437 .helper_attrs
438 .iter()
439 .map(|(_, ident)| {
440 let res = Res::NonMacroAttr(NonMacroAttrKind::DeriveHelper);
441 let binding = (res, Visibility::<DefId>::Public, ident.span, expn_id)
442 .to_name_binding(self.arenas);
443 (*ident, binding)
444 })
445 .collect();
446 self.helper_attrs.insert(expn_id, helper_attrs);
447 if entry.has_derive_copy || self.has_derive_copy(parent_scope.expansion) {
450 self.containers_deriving_copy.insert(expn_id);
451 }
452 assert!(self.derive_data.is_empty());
453 self.derive_data = derive_data;
454 Ok(())
455 }
456
457 fn take_derive_resolutions(&mut self, expn_id: LocalExpnId) -> Option<Vec<DeriveResolution>> {
458 self.derive_data.remove(&expn_id).map(|data| data.resolutions)
459 }
460
461 fn cfg_accessible(
466 &mut self,
467 expn_id: LocalExpnId,
468 path: &ast::Path,
469 ) -> Result<bool, Indeterminate> {
470 self.path_accessible(expn_id, path, &[TypeNS, ValueNS, MacroNS])
471 }
472
473 fn macro_accessible(
474 &mut self,
475 expn_id: LocalExpnId,
476 path: &ast::Path,
477 ) -> Result<bool, Indeterminate> {
478 self.path_accessible(expn_id, path, &[MacroNS])
479 }
480
481 fn get_proc_macro_quoted_span(&self, krate: CrateNum, id: usize) -> Span {
482 self.cstore().get_proc_macro_quoted_span_untracked(krate, id, self.tcx.sess)
483 }
484
485 fn declare_proc_macro(&mut self, id: NodeId) {
486 self.proc_macros.push(self.local_def_id(id))
487 }
488
489 fn append_stripped_cfg_item(&mut self, parent_node: NodeId, ident: Ident, cfg: ast::MetaItem) {
490 self.stripped_cfg_items.push(StrippedCfgItem { parent_module: parent_node, ident, cfg });
491 }
492
493 fn registered_tools(&self) -> &RegisteredTools {
494 self.registered_tools
495 }
496
497 fn register_glob_delegation(&mut self, invoc_id: LocalExpnId) {
498 self.glob_delegation_invoc_ids.insert(invoc_id);
499 }
500
501 fn glob_delegation_suffixes(
502 &mut self,
503 trait_def_id: DefId,
504 impl_def_id: LocalDefId,
505 ) -> Result<Vec<(Ident, Option<Ident>)>, Indeterminate> {
506 let target_trait = self.expect_module(trait_def_id);
507 if !target_trait.unexpanded_invocations.borrow().is_empty() {
508 return Err(Indeterminate);
509 }
510 if let Some(unexpanded_invocations) = self.impl_unexpanded_invocations.get(&impl_def_id)
517 && !unexpanded_invocations.is_empty()
518 {
519 return Err(Indeterminate);
520 }
521
522 let mut idents = Vec::new();
523 target_trait.for_each_child(self, |this, ident, ns, _binding| {
524 if let Some(overriding_keys) = this.impl_binding_keys.get(&impl_def_id)
526 && overriding_keys.contains(&BindingKey::new(ident.normalize_to_macros_2_0(), ns))
527 {
528 } else {
530 idents.push((ident, None));
531 }
532 });
533 Ok(idents)
534 }
535
536 fn insert_impl_trait_name(&mut self, id: NodeId, name: Symbol) {
537 self.impl_trait_names.insert(id, name);
538 }
539}
540
541impl<'ra, 'tcx> Resolver<'ra, 'tcx> {
542 fn smart_resolve_macro_path(
546 &mut self,
547 path: &ast::Path,
548 kind: MacroKind,
549 supports_macro_expansion: SupportsMacroExpansion,
550 inner_attr: bool,
551 parent_scope: &ParentScope<'ra>,
552 node_id: NodeId,
553 force: bool,
554 deleg_impl: Option<LocalDefId>,
555 invoc_in_mod_inert_attr: Option<LocalDefId>,
556 suggestion_span: Option<Span>,
557 ) -> Result<(Arc<SyntaxExtension>, Res), Indeterminate> {
558 let (ext, res) = match self.resolve_macro_or_delegation_path(
559 path,
560 Some(kind),
561 parent_scope,
562 true,
563 force,
564 deleg_impl,
565 invoc_in_mod_inert_attr.map(|def_id| (def_id, node_id)),
566 None,
567 suggestion_span,
568 ) {
569 Ok((Some(ext), res)) => (ext, res),
570 Ok((None, res)) => (self.dummy_ext(kind), res),
571 Err(Determinacy::Determined) => (self.dummy_ext(kind), Res::Err),
572 Err(Determinacy::Undetermined) => return Err(Indeterminate),
573 };
574
575 if deleg_impl.is_some() {
577 if !matches!(res, Res::Err | Res::Def(DefKind::Trait, _)) {
578 self.dcx().emit_err(MacroExpectedFound {
579 span: path.span,
580 expected: "trait",
581 article: "a",
582 found: res.descr(),
583 macro_path: &pprust::path_to_string(path),
584 remove_surrounding_derive: None,
585 add_as_non_derive: None,
586 });
587 return Ok((self.dummy_ext(kind), Res::Err));
588 }
589
590 return Ok((ext, res));
591 }
592
593 for segment in &path.segments {
595 if let Some(args) = &segment.args {
596 self.dcx().emit_err(errors::GenericArgumentsInMacroPath { span: args.span() });
597 }
598 if kind == MacroKind::Attr && segment.ident.as_str().starts_with("rustc") {
599 self.dcx().emit_err(errors::AttributesStartingWithRustcAreReserved {
600 span: segment.ident.span,
601 });
602 }
603 }
604
605 match res {
606 Res::Def(DefKind::Macro(_), def_id) => {
607 if let Some(def_id) = def_id.as_local() {
608 self.unused_macros.swap_remove(&def_id);
609 if self.proc_macro_stubs.contains(&def_id) {
610 self.dcx().emit_err(errors::ProcMacroSameCrate {
611 span: path.span,
612 is_test: self.tcx.sess.is_test_crate(),
613 });
614 }
615 }
616 }
617 Res::NonMacroAttr(..) | Res::Err => {}
618 _ => panic!("expected `DefKind::Macro` or `Res::NonMacroAttr`"),
619 };
620
621 self.check_stability_and_deprecation(&ext, path, node_id);
622
623 let unexpected_res = if ext.macro_kind() != kind {
624 Some((kind.article(), kind.descr_expected()))
625 } else if matches!(res, Res::Def(..)) {
626 match supports_macro_expansion {
627 SupportsMacroExpansion::No => Some(("a", "non-macro attribute")),
628 SupportsMacroExpansion::Yes { supports_inner_attrs } => {
629 if inner_attr && !supports_inner_attrs {
630 Some(("a", "non-macro inner attribute"))
631 } else {
632 None
633 }
634 }
635 }
636 } else {
637 None
638 };
639 if let Some((article, expected)) = unexpected_res {
640 let path_str = pprust::path_to_string(path);
641
642 let mut err = MacroExpectedFound {
643 span: path.span,
644 expected,
645 article,
646 found: res.descr(),
647 macro_path: &path_str,
648 remove_surrounding_derive: None,
649 add_as_non_derive: None,
650 };
651
652 if !path.span.from_expansion()
654 && kind == MacroKind::Derive
655 && ext.macro_kind() != MacroKind::Derive
656 {
657 err.remove_surrounding_derive = Some(RemoveSurroundingDerive { span: path.span });
658 err.add_as_non_derive = Some(AddAsNonDerive { macro_path: &path_str });
659 }
660
661 self.dcx().emit_err(err);
662
663 return Ok((self.dummy_ext(kind), Res::Err));
664 }
665
666 if res != Res::Err && inner_attr && !self.tcx.features().custom_inner_attributes() {
668 let is_macro = match res {
669 Res::Def(..) => true,
670 Res::NonMacroAttr(..) => false,
671 _ => unreachable!(),
672 };
673 let msg = if is_macro {
674 "inner macro attributes are unstable"
675 } else {
676 "custom inner attributes are unstable"
677 };
678 feature_err(&self.tcx.sess, sym::custom_inner_attributes, path.span, msg).emit();
679 }
680
681 if res == Res::NonMacroAttr(NonMacroAttrKind::Tool)
682 && let [namespace, attribute, ..] = &*path.segments
683 && namespace.ident.name == sym::diagnostic
684 && ![sym::on_unimplemented, sym::do_not_recommend].contains(&attribute.ident.name)
685 {
686 let typo_name = find_best_match_for_name(
687 &[sym::on_unimplemented, sym::do_not_recommend],
688 attribute.ident.name,
689 Some(5),
690 );
691
692 self.tcx.sess.psess.buffer_lint(
693 UNKNOWN_OR_MALFORMED_DIAGNOSTIC_ATTRIBUTES,
694 attribute.span(),
695 node_id,
696 BuiltinLintDiag::UnknownDiagnosticAttribute { span: attribute.span(), typo_name },
697 );
698 }
699
700 Ok((ext, res))
701 }
702
703 pub(crate) fn resolve_macro_path(
704 &mut self,
705 path: &ast::Path,
706 kind: Option<MacroKind>,
707 parent_scope: &ParentScope<'ra>,
708 trace: bool,
709 force: bool,
710 ignore_import: Option<Import<'ra>>,
711 suggestion_span: Option<Span>,
712 ) -> Result<(Option<Arc<SyntaxExtension>>, Res), Determinacy> {
713 self.resolve_macro_or_delegation_path(
714 path,
715 kind,
716 parent_scope,
717 trace,
718 force,
719 None,
720 None,
721 ignore_import,
722 suggestion_span,
723 )
724 }
725
726 fn resolve_macro_or_delegation_path(
727 &mut self,
728 ast_path: &ast::Path,
729 kind: Option<MacroKind>,
730 parent_scope: &ParentScope<'ra>,
731 trace: bool,
732 force: bool,
733 deleg_impl: Option<LocalDefId>,
734 invoc_in_mod_inert_attr: Option<(LocalDefId, NodeId)>,
735 ignore_import: Option<Import<'ra>>,
736 suggestion_span: Option<Span>,
737 ) -> Result<(Option<Arc<SyntaxExtension>>, Res), Determinacy> {
738 let path_span = ast_path.span;
739 let mut path = Segment::from_path(ast_path);
740
741 if deleg_impl.is_none()
743 && kind == Some(MacroKind::Bang)
744 && let [segment] = path.as_slice()
745 && segment.ident.span.ctxt().outer_expn_data().local_inner_macros
746 {
747 let root = Ident::new(kw::DollarCrate, segment.ident.span);
748 path.insert(0, Segment::from_ident(root));
749 }
750
751 let res = if deleg_impl.is_some() || path.len() > 1 {
752 let ns = if deleg_impl.is_some() { TypeNS } else { MacroNS };
753 let res = match self.maybe_resolve_path(&path, Some(ns), parent_scope, ignore_import) {
754 PathResult::NonModule(path_res) if let Some(res) = path_res.full_res() => Ok(res),
755 PathResult::Indeterminate if !force => return Err(Determinacy::Undetermined),
756 PathResult::NonModule(..)
757 | PathResult::Indeterminate
758 | PathResult::Failed { .. } => Err(Determinacy::Determined),
759 PathResult::Module(ModuleOrUniformRoot::Module(module)) => {
760 Ok(module.res().unwrap())
761 }
762 PathResult::Module(..) => unreachable!(),
763 };
764
765 if trace {
766 let kind = kind.expect("macro kind must be specified if tracing is enabled");
767 self.multi_segment_macro_resolutions.push((
768 path,
769 path_span,
770 kind,
771 *parent_scope,
772 res.ok(),
773 ns,
774 ));
775 }
776
777 self.prohibit_imported_non_macro_attrs(None, res.ok(), path_span);
778 res
779 } else {
780 let scope_set = kind.map_or(ScopeSet::All(MacroNS), ScopeSet::Macro);
781 let binding = self.early_resolve_ident_in_lexical_scope(
782 path[0].ident,
783 scope_set,
784 parent_scope,
785 None,
786 force,
787 None,
788 None,
789 );
790 if let Err(Determinacy::Undetermined) = binding {
791 return Err(Determinacy::Undetermined);
792 }
793
794 if trace {
795 let kind = kind.expect("macro kind must be specified if tracing is enabled");
796 self.single_segment_macro_resolutions.push((
797 path[0].ident,
798 kind,
799 *parent_scope,
800 binding.ok(),
801 suggestion_span,
802 ));
803 }
804
805 let res = binding.map(|binding| binding.res());
806 self.prohibit_imported_non_macro_attrs(binding.ok(), res.ok(), path_span);
807 self.report_out_of_scope_macro_calls(
808 ast_path,
809 parent_scope,
810 invoc_in_mod_inert_attr,
811 binding.ok(),
812 );
813 res
814 };
815
816 let res = res?;
817 let ext = match deleg_impl {
818 Some(impl_def_id) => match res {
819 def::Res::Def(DefKind::Trait, def_id) => {
820 let edition = self.tcx.sess.edition();
821 Some(Arc::new(SyntaxExtension::glob_delegation(def_id, impl_def_id, edition)))
822 }
823 _ => None,
824 },
825 None => self.get_macro(res).map(|macro_data| Arc::clone(¯o_data.ext)),
826 };
827 Ok((ext, res))
828 }
829
830 pub(crate) fn finalize_macro_resolutions(&mut self, krate: &Crate) {
831 let check_consistency = |this: &mut Self,
832 path: &[Segment],
833 span,
834 kind: MacroKind,
835 initial_res: Option<Res>,
836 res: Res| {
837 if let Some(initial_res) = initial_res {
838 if res != initial_res {
839 this.dcx().span_delayed_bug(span, "inconsistent resolution for a macro");
843 }
844 } else if this.tcx.dcx().has_errors().is_none() && this.privacy_errors.is_empty() {
845 let err = this.dcx().create_err(CannotDetermineMacroResolution {
854 span,
855 kind: kind.descr(),
856 path: Segment::names_to_string(path),
857 });
858 err.stash(span, StashKey::UndeterminedMacroResolution);
859 }
860 };
861
862 let macro_resolutions = mem::take(&mut self.multi_segment_macro_resolutions);
863 for (mut path, path_span, kind, parent_scope, initial_res, ns) in macro_resolutions {
864 for seg in &mut path {
866 seg.id = None;
867 }
868 match self.resolve_path(
869 &path,
870 Some(ns),
871 &parent_scope,
872 Some(Finalize::new(ast::CRATE_NODE_ID, path_span)),
873 None,
874 None,
875 ) {
876 PathResult::NonModule(path_res) if let Some(res) = path_res.full_res() => {
877 check_consistency(self, &path, path_span, kind, initial_res, res)
878 }
879 PathResult::Module(ModuleOrUniformRoot::Module(module)) => check_consistency(
881 self,
882 &path,
883 path_span,
884 kind,
885 initial_res,
886 module.res().unwrap(),
887 ),
888 path_res @ (PathResult::NonModule(..) | PathResult::Failed { .. }) => {
889 let mut suggestion = None;
890 let (span, label, module, segment) =
891 if let PathResult::Failed { span, label, module, segment_name, .. } =
892 path_res
893 {
894 if let PathResult::NonModule(partial_res) =
896 self.maybe_resolve_path(&path, Some(ValueNS), &parent_scope, None)
897 && partial_res.unresolved_segments() == 0
898 {
899 let sm = self.tcx.sess.source_map();
900 let exclamation_span = sm.next_point(span);
901 suggestion = Some((
902 vec![(exclamation_span, "".to_string())],
903 format!(
904 "{} is not a macro, but a {}, try to remove `!`",
905 Segment::names_to_string(&path),
906 partial_res.base_res().descr()
907 ),
908 Applicability::MaybeIncorrect,
909 ));
910 }
911 (span, label, module, segment_name)
912 } else {
913 (
914 path_span,
915 format!(
916 "partially resolved path in {} {}",
917 kind.article(),
918 kind.descr()
919 ),
920 None,
921 path.last().map(|segment| segment.ident.name).unwrap(),
922 )
923 };
924 self.report_error(
925 span,
926 ResolutionError::FailedToResolve {
927 segment: Some(segment),
928 label,
929 suggestion,
930 module,
931 },
932 );
933 }
934 PathResult::Module(..) | PathResult::Indeterminate => unreachable!(),
935 }
936 }
937
938 let macro_resolutions = mem::take(&mut self.single_segment_macro_resolutions);
939 for (ident, kind, parent_scope, initial_binding, sugg_span) in macro_resolutions {
940 match self.early_resolve_ident_in_lexical_scope(
941 ident,
942 ScopeSet::Macro(kind),
943 &parent_scope,
944 Some(Finalize::new(ast::CRATE_NODE_ID, ident.span)),
945 true,
946 None,
947 None,
948 ) {
949 Ok(binding) => {
950 let initial_res = initial_binding.map(|initial_binding| {
951 self.record_use(ident, initial_binding, Used::Other);
952 initial_binding.res()
953 });
954 let res = binding.res();
955 let seg = Segment::from_ident(ident);
956 check_consistency(self, &[seg], ident.span, kind, initial_res, res);
957 if res == Res::NonMacroAttr(NonMacroAttrKind::DeriveHelperCompat) {
958 let node_id = self
959 .invocation_parents
960 .get(&parent_scope.expansion)
961 .map_or(ast::CRATE_NODE_ID, |parent| {
962 self.def_id_to_node_id(parent.parent_def)
963 });
964 self.lint_buffer.buffer_lint(
965 LEGACY_DERIVE_HELPERS,
966 node_id,
967 ident.span,
968 BuiltinLintDiag::LegacyDeriveHelpers(binding.span),
969 );
970 }
971 }
972 Err(..) => {
973 let expected = kind.descr_expected();
974
975 let mut err = self.dcx().create_err(CannotFindIdentInThisScope {
976 span: ident.span,
977 expected,
978 ident,
979 });
980 self.unresolved_macro_suggestions(
981 &mut err,
982 kind,
983 &parent_scope,
984 ident,
985 krate,
986 sugg_span,
987 );
988 err.emit();
989 }
990 }
991 }
992
993 let builtin_attrs = mem::take(&mut self.builtin_attrs);
994 for (ident, parent_scope) in builtin_attrs {
995 let _ = self.early_resolve_ident_in_lexical_scope(
996 ident,
997 ScopeSet::Macro(MacroKind::Attr),
998 &parent_scope,
999 Some(Finalize::new(ast::CRATE_NODE_ID, ident.span)),
1000 true,
1001 None,
1002 None,
1003 );
1004 }
1005 }
1006
1007 fn check_stability_and_deprecation(
1008 &mut self,
1009 ext: &SyntaxExtension,
1010 path: &ast::Path,
1011 node_id: NodeId,
1012 ) {
1013 let span = path.span;
1014 if let Some(stability) = &ext.stability {
1015 if let StabilityLevel::Unstable { reason, issue, is_soft, implied_by, .. } =
1016 stability.level
1017 {
1018 let feature = stability.feature;
1019
1020 let is_allowed =
1021 |feature| self.tcx.features().enabled(feature) || span.allows_unstable(feature);
1022 let allowed_by_implication = implied_by.is_some_and(|feature| is_allowed(feature));
1023 if !is_allowed(feature) && !allowed_by_implication {
1024 let lint_buffer = &mut self.lint_buffer;
1025 let soft_handler = |lint, span, msg: String| {
1026 lint_buffer.buffer_lint(
1027 lint,
1028 node_id,
1029 span,
1030 BuiltinLintDiag::UnstableFeature(
1031 msg.into(),
1033 ),
1034 )
1035 };
1036 stability::report_unstable(
1037 self.tcx.sess,
1038 feature,
1039 reason.to_opt_reason(),
1040 issue,
1041 None,
1042 is_soft,
1043 span,
1044 soft_handler,
1045 stability::UnstableKind::Regular,
1046 );
1047 }
1048 }
1049 }
1050 if let Some(depr) = &ext.deprecation {
1051 let path = pprust::path_to_string(path);
1052 stability::early_report_macro_deprecation(
1053 &mut self.lint_buffer,
1054 depr,
1055 span,
1056 node_id,
1057 path,
1058 );
1059 }
1060 }
1061
1062 fn prohibit_imported_non_macro_attrs(
1063 &self,
1064 binding: Option<NameBinding<'ra>>,
1065 res: Option<Res>,
1066 span: Span,
1067 ) {
1068 if let Some(Res::NonMacroAttr(kind)) = res {
1069 if kind != NonMacroAttrKind::Tool && binding.is_none_or(|b| b.is_import()) {
1070 let binding_span = binding.map(|binding| binding.span);
1071 self.dcx().emit_err(errors::CannotUseThroughAnImport {
1072 span,
1073 article: kind.article(),
1074 descr: kind.descr(),
1075 binding_span,
1076 });
1077 }
1078 }
1079 }
1080
1081 fn report_out_of_scope_macro_calls(
1082 &mut self,
1083 path: &ast::Path,
1084 parent_scope: &ParentScope<'ra>,
1085 invoc_in_mod_inert_attr: Option<(LocalDefId, NodeId)>,
1086 binding: Option<NameBinding<'ra>>,
1087 ) {
1088 if let Some((mod_def_id, node_id)) = invoc_in_mod_inert_attr
1089 && let Some(binding) = binding
1090 && let NameBindingKind::Res(res) = binding.kind
1092 && let Res::Def(DefKind::Macro(MacroKind::Bang), def_id) = res
1093 && self.tcx.is_descendant_of(def_id, mod_def_id.to_def_id())
1096 {
1097 let no_macro_rules = self.arenas.alloc_macro_rules_scope(MacroRulesScope::Empty);
1101 let fallback_binding = self.early_resolve_ident_in_lexical_scope(
1102 path.segments[0].ident,
1103 ScopeSet::Macro(MacroKind::Bang),
1104 &ParentScope { macro_rules: no_macro_rules, ..*parent_scope },
1105 None,
1106 false,
1107 None,
1108 None,
1109 );
1110 if fallback_binding.ok().and_then(|b| b.res().opt_def_id()) != Some(def_id) {
1111 let location = match parent_scope.module.kind {
1112 ModuleKind::Def(kind, def_id, name) => {
1113 if let Some(name) = name {
1114 format!("{} `{name}`", kind.descr(def_id))
1115 } else {
1116 "the crate root".to_string()
1117 }
1118 }
1119 ModuleKind::Block => "this scope".to_string(),
1120 };
1121 self.tcx.sess.psess.buffer_lint(
1122 OUT_OF_SCOPE_MACRO_CALLS,
1123 path.span,
1124 node_id,
1125 BuiltinLintDiag::OutOfScopeMacroCalls {
1126 span: path.span,
1127 path: pprust::path_to_string(path),
1128 location,
1129 },
1130 );
1131 }
1132 }
1133 }
1134
1135 pub(crate) fn check_reserved_macro_name(&mut self, ident: Ident, res: Res) {
1136 if ident.name == sym::cfg || ident.name == sym::cfg_attr {
1139 let macro_kind = self.get_macro(res).map(|macro_data| macro_data.ext.macro_kind());
1140 if macro_kind.is_some() && sub_namespace_match(macro_kind, Some(MacroKind::Attr)) {
1141 self.dcx()
1142 .emit_err(errors::NameReservedInAttributeNamespace { span: ident.span, ident });
1143 }
1144 }
1145 }
1146
1147 pub(crate) fn compile_macro(
1151 &mut self,
1152 macro_def: &ast::MacroDef,
1153 ident: Ident,
1154 attrs: &[rustc_hir::Attribute],
1155 span: Span,
1156 node_id: NodeId,
1157 edition: Edition,
1158 ) -> MacroData {
1159 let (mut ext, mut nrules) = compile_declarative_macro(
1160 self.tcx.sess,
1161 self.tcx.features(),
1162 macro_def,
1163 ident,
1164 attrs,
1165 span,
1166 node_id,
1167 edition,
1168 );
1169
1170 if let Some(builtin_name) = ext.builtin_name {
1171 if let Some(builtin_ext_kind) = self.builtin_macros.get(&builtin_name) {
1173 ext.kind = builtin_ext_kind.clone();
1176 nrules = 0;
1177 } else {
1178 self.dcx().emit_err(errors::CannotFindBuiltinMacroWithName { span, ident });
1179 }
1180 }
1181
1182 MacroData { ext: Arc::new(ext), nrules, macro_rules: macro_def.macro_rules }
1183 }
1184
1185 fn path_accessible(
1186 &mut self,
1187 expn_id: LocalExpnId,
1188 path: &ast::Path,
1189 namespaces: &[Namespace],
1190 ) -> Result<bool, Indeterminate> {
1191 let span = path.span;
1192 let path = &Segment::from_path(path);
1193 let parent_scope = self.invocation_parent_scopes[&expn_id];
1194
1195 let mut indeterminate = false;
1196 for ns in namespaces {
1197 match self.maybe_resolve_path(path, Some(*ns), &parent_scope, None) {
1198 PathResult::Module(ModuleOrUniformRoot::Module(_)) => return Ok(true),
1199 PathResult::NonModule(partial_res) if partial_res.unresolved_segments() == 0 => {
1200 return Ok(true);
1201 }
1202 PathResult::NonModule(..) |
1203 PathResult::Failed { is_error_from_last_segment: false, .. } => {
1205 self.dcx()
1206 .emit_err(errors::CfgAccessibleUnsure { span });
1207
1208 return Ok(false);
1211 }
1212 PathResult::Indeterminate => indeterminate = true,
1213 PathResult::Failed { .. } => {}
1216 PathResult::Module(_) => panic!("unexpected path resolution"),
1217 }
1218 }
1219
1220 if indeterminate {
1221 return Err(Indeterminate);
1222 }
1223
1224 Ok(false)
1225 }
1226}