clang 22.0.0git
Lookup.h
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1//===- Lookup.h - Classes for name lookup -----------------------*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines the LookupResult class, which is integral to
10// Sema's name-lookup subsystem.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_CLANG_SEMA_LOOKUP_H
15#define LLVM_CLANG_SEMA_LOOKUP_H
16
17#include "clang/AST/Decl.h"
18#include "clang/AST/DeclBase.h"
19#include "clang/AST/DeclCXX.h"
21#include "clang/AST/Type.h"
23#include "clang/Basic/LLVM.h"
27#include "clang/Sema/Sema.h"
28#include "llvm/ADT/MapVector.h"
29#include "llvm/ADT/STLExtras.h"
30#include "llvm/Support/Casting.h"
31#include <cassert>
32#include <optional>
33#include <utility>
34
35namespace clang {
36
37class CXXBasePaths;
38
39enum class LookupResultKind {
40 /// No entity found met the criteria.
41 NotFound = 0,
42
43 /// No entity found met the criteria within the current
44 /// instantiation,, but there were dependent base classes of the
45 /// current instantiation that could not be searched.
47
48 /// Name lookup found a single declaration that met the
49 /// criteria. getFoundDecl() will return this declaration.
50 Found,
51
52 /// Name lookup found a set of overloaded functions that
53 /// met the criteria.
55
56 /// Name lookup found an unresolvable value declaration
57 /// and cannot yet complete. This only happens in C++ dependent
58 /// contexts with dependent using declarations.
60
61 /// Name lookup results in an ambiguity; use
62 /// getAmbiguityKind to figure out what kind of ambiguity
63 /// we have.
65};
66
68 /// Name lookup results in an ambiguity because multiple
69 /// entities that meet the lookup criteria were found in
70 /// subobjects of different types. For example:
71 /// @code
72 /// struct A { void f(int); }
73 /// struct B { void f(double); }
74 /// struct C : A, B { };
75 /// void test(C c) {
76 /// c.f(0); // error: A::f and B::f come from subobjects of different
77 /// // types. overload resolution is not performed.
78 /// }
79 /// @endcode
81
82 /// Name lookup results in an ambiguity because multiple
83 /// nonstatic entities that meet the lookup criteria were found
84 /// in different subobjects of the same type. For example:
85 /// @code
86 /// struct A { int x; };
87 /// struct B : A { };
88 /// struct C : A { };
89 /// struct D : B, C { };
90 /// int test(D d) {
91 /// return d.x; // error: 'x' is found in two A subobjects (of B and C)
92 /// }
93 /// @endcode
95
96 /// Name lookup results in an ambiguity because multiple definitions
97 /// of entity that meet the lookup criteria were found in different
98 /// declaration contexts.
99 /// @code
100 /// namespace A {
101 /// int i;
102 /// namespace B { int i; }
103 /// int test() {
104 /// using namespace B;
105 /// return i; // error 'i' is found in namespace A and A::B
106 /// }
107 /// }
108 /// @endcode
110
111 /// Name lookup results in an ambiguity because multiple placeholder
112 /// variables were found in the same scope.
113 /// @code
114 /// void f() {
115 /// int _ = 0;
116 /// int _ = 0;
117 /// return _; // ambiguous use of placeholder variable
118 /// }
119 /// @endcode
121
122 /// Name lookup results in an ambiguity because an entity with a
123 /// tag name was hidden by an entity with an ordinary name from
124 /// a different context.
125 /// @code
126 /// namespace A { struct Foo {}; }
127 /// namespace B { void Foo(); }
128 /// namespace C {
129 /// using namespace A;
130 /// using namespace B;
131 /// }
132 /// void test() {
133 /// C::Foo(); // error: tag 'A::Foo' is hidden by an object in a
134 /// // different namespace
135 /// }
136 /// @endcode
138};
139
140/// Represents the results of name lookup.
141///
142/// An instance of the LookupResult class captures the results of a
143/// single name lookup, which can return no result (nothing found),
144/// a single declaration, a set of overloaded functions, or an
145/// ambiguity. Use the getKind() method to determine which of these
146/// results occurred for a given lookup.
148public:
149 /// A little identifier for flagging temporary lookup results.
152 };
153
155
157 Sema &SemaRef, const DeclarationNameInfo &NameInfo,
158 Sema::LookupNameKind LookupKind,
159 RedeclarationKind Redecl = RedeclarationKind::NotForRedeclaration)
160 : SemaPtr(&SemaRef), NameInfo(NameInfo), LookupKind(LookupKind),
161 Redecl(Redecl != RedeclarationKind::NotForRedeclaration),
162 ExternalRedecl(Redecl == RedeclarationKind::ForExternalRedeclaration),
163 DiagnoseAccess(Redecl == RedeclarationKind::NotForRedeclaration),
164 DiagnoseAmbiguous(Redecl == RedeclarationKind::NotForRedeclaration) {
165 configure();
166 }
167
168 // TODO: consider whether this constructor should be restricted to take
169 // as input a const IdentifierInfo* (instead of Name),
170 // forcing other cases towards the constructor taking a DNInfo.
172 Sema &SemaRef, DeclarationName Name, SourceLocation NameLoc,
173 Sema::LookupNameKind LookupKind,
174 RedeclarationKind Redecl = RedeclarationKind::NotForRedeclaration)
175 : SemaPtr(&SemaRef), NameInfo(Name, NameLoc), LookupKind(LookupKind),
176 Redecl(Redecl != RedeclarationKind::NotForRedeclaration),
177 ExternalRedecl(Redecl == RedeclarationKind::ForExternalRedeclaration),
178 DiagnoseAccess(Redecl == RedeclarationKind::NotForRedeclaration),
179 DiagnoseAmbiguous(Redecl == RedeclarationKind::NotForRedeclaration) {
180 configure();
181 }
182
183 /// Creates a temporary lookup result, initializing its core data
184 /// using the information from another result. Diagnostics are always
185 /// disabled.
187 : SemaPtr(Other.SemaPtr), NameInfo(Other.NameInfo),
188 LookupKind(Other.LookupKind), IDNS(Other.IDNS), Redecl(Other.Redecl),
189 ExternalRedecl(Other.ExternalRedecl), HideTags(Other.HideTags),
190 AllowHidden(Other.AllowHidden),
191 TemplateNameLookup(Other.TemplateNameLookup) {}
192
193 // FIXME: Remove these deleted methods once the default build includes
194 // -Wdeprecated.
195 LookupResult(const LookupResult &) = delete;
197
199 : ResultKind(std::move(Other.ResultKind)),
200 Ambiguity(std::move(Other.Ambiguity)), Decls(std::move(Other.Decls)),
201 Paths(std::move(Other.Paths)),
202 NamingClass(std::move(Other.NamingClass)),
203 BaseObjectType(std::move(Other.BaseObjectType)),
204 SemaPtr(std::move(Other.SemaPtr)), NameInfo(std::move(Other.NameInfo)),
205 NameContextRange(std::move(Other.NameContextRange)),
206 LookupKind(std::move(Other.LookupKind)), IDNS(std::move(Other.IDNS)),
207 Redecl(std::move(Other.Redecl)),
208 ExternalRedecl(std::move(Other.ExternalRedecl)),
209 HideTags(std::move(Other.HideTags)),
210 DiagnoseAccess(std::move(Other.DiagnoseAccess)),
211 DiagnoseAmbiguous(std::move(Other.DiagnoseAmbiguous)),
212 AllowHidden(std::move(Other.AllowHidden)),
213 Shadowed(std::move(Other.Shadowed)),
214 TemplateNameLookup(std::move(Other.TemplateNameLookup)) {
215 Other.Paths = nullptr;
216 Other.DiagnoseAccess = false;
217 Other.DiagnoseAmbiguous = false;
218 }
219
221 ResultKind = std::move(Other.ResultKind);
222 Ambiguity = std::move(Other.Ambiguity);
223 Decls = std::move(Other.Decls);
224 Paths = std::move(Other.Paths);
225 NamingClass = std::move(Other.NamingClass);
226 BaseObjectType = std::move(Other.BaseObjectType);
227 SemaPtr = std::move(Other.SemaPtr);
228 NameInfo = std::move(Other.NameInfo);
229 NameContextRange = std::move(Other.NameContextRange);
230 LookupKind = std::move(Other.LookupKind);
231 IDNS = std::move(Other.IDNS);
232 Redecl = std::move(Other.Redecl);
233 ExternalRedecl = std::move(Other.ExternalRedecl);
234 HideTags = std::move(Other.HideTags);
235 DiagnoseAccess = std::move(Other.DiagnoseAccess);
236 DiagnoseAmbiguous = std::move(Other.DiagnoseAmbiguous);
237 AllowHidden = std::move(Other.AllowHidden);
238 Shadowed = std::move(Other.Shadowed);
239 TemplateNameLookup = std::move(Other.TemplateNameLookup);
240 Other.Paths = nullptr;
241 Other.DiagnoseAccess = false;
242 Other.DiagnoseAmbiguous = false;
243 return *this;
244 }
245
247 if (DiagnoseAccess)
248 diagnoseAccess();
249 if (DiagnoseAmbiguous)
250 diagnoseAmbiguous();
251 if (Paths) deletePaths(Paths);
252 }
253
254 /// Gets the name info to look up.
256 return NameInfo;
257 }
258
259 /// Sets the name info to look up.
261 this->NameInfo = NameInfo;
262 }
263
264 /// Gets the name to look up.
266 return NameInfo.getName();
267 }
268
269 /// Sets the name to look up.
271 NameInfo.setName(Name);
272 }
273
274 /// Gets the kind of lookup to perform.
276 return LookupKind;
277 }
278
279 /// True if this lookup is just looking for an existing declaration.
280 bool isForRedeclaration() const {
281 return Redecl;
282 }
283
284 /// True if this lookup is just looking for an existing declaration to link
285 /// against a declaration with external linkage.
287 return ExternalRedecl;
288 }
289
291 return ExternalRedecl ? RedeclarationKind::ForExternalRedeclaration
292 : Redecl ? RedeclarationKind::ForVisibleRedeclaration
293 : RedeclarationKind::NotForRedeclaration;
294 }
295
296 /// Specify whether hidden declarations are visible, e.g.,
297 /// for recovery reasons.
298 void setAllowHidden(bool AH) {
299 AllowHidden = AH;
300 }
301
302 /// Determine whether this lookup is permitted to see hidden
303 /// declarations, such as those in modules that have not yet been imported.
305 return AllowHidden ||
307 }
308
309 /// Sets whether tag declarations should be hidden by non-tag
310 /// declarations during resolution. The default is true.
311 void setHideTags(bool Hide) {
312 HideTags = Hide;
313 }
314
315 /// Sets whether this is a template-name lookup. For template-name lookups,
316 /// injected-class-names are treated as naming a template rather than a
317 /// template specialization.
319 TemplateNameLookup = TemplateName;
320 }
321
322 bool isTemplateNameLookup() const { return TemplateNameLookup; }
323
324 bool isAmbiguous() const {
326 }
327
328 /// Determines if this names a single result which is not an
329 /// unresolved value using decl. If so, it is safe to call
330 /// getFoundDecl().
331 bool isSingleResult() const {
333 }
334
335 /// Determines if the results are overloaded.
336 bool isOverloadedResult() const {
338 }
339
340 bool isUnresolvableResult() const {
342 }
343
345 assert(checkDebugAssumptions());
346 return ResultKind;
347 }
348
350 assert(isAmbiguous());
351 return Ambiguity;
352 }
353
355 return Decls;
356 }
357
358 iterator begin() const { return iterator(Decls.begin()); }
359 iterator end() const { return iterator(Decls.end()); }
360
361 /// Return true if no decls were found
362 bool empty() const { return Decls.empty(); }
363
364 /// Return the base paths structure that's associated with
365 /// these results, or null if none is.
367 return Paths;
368 }
369
370 /// Determine whether the given declaration is visible to the
371 /// program.
372 static bool isVisible(Sema &SemaRef, NamedDecl *D);
373
374 static bool isReachable(Sema &SemaRef, NamedDecl *D);
375
376 static bool isAcceptable(Sema &SemaRef, NamedDecl *D,
378 return Kind == Sema::AcceptableKind::Visible ? isVisible(SemaRef, D)
379 : isReachable(SemaRef, D);
380 }
381
382 /// Determine whether this lookup is permitted to see the declaration.
383 /// Note that a reachable but not visible declaration inhabiting a namespace
384 /// is not allowed to be seen during name lookup.
385 ///
386 /// For example:
387 /// ```
388 /// // m.cppm
389 /// export module m;
390 /// struct reachable { int v; }
391 /// export auto func() { return reachable{43}; }
392 /// // Use.cpp
393 /// import m;
394 /// auto Use() {
395 /// // Not valid. We couldn't see reachable here.
396 /// // So isAvailableForLookup would return false when we look
397 /// up 'reachable' here.
398 /// // return reachable(43).v;
399 /// // Valid. The field name 'v' is allowed during name lookup.
400 /// // So isAvailableForLookup would return true when we look up 'v' here.
401 /// return func().v;
402 /// }
403 /// ```
404 static bool isAvailableForLookup(Sema &SemaRef, NamedDecl *ND);
405
406 /// Retrieve the accepted (re)declaration of the given declaration,
407 /// if there is one.
409 if (!D->isInIdentifierNamespace(IDNS))
410 return nullptr;
411
413 return D;
414
415 return getAcceptableDeclSlow(D);
416 }
417
418private:
419 static bool isAcceptableSlow(Sema &SemaRef, NamedDecl *D,
421 static bool isReachableSlow(Sema &SemaRef, NamedDecl *D);
422 NamedDecl *getAcceptableDeclSlow(NamedDecl *D) const;
423
424public:
425 /// Returns the identifier namespace mask for this lookup.
426 unsigned getIdentifierNamespace() const {
427 return IDNS;
428 }
429
430 /// Returns whether these results arose from performing a
431 /// lookup into a class.
432 bool isClassLookup() const {
433 return NamingClass != nullptr;
434 }
435
436 /// Returns the 'naming class' for this lookup, i.e. the
437 /// class which was looked into to find these results.
438 ///
439 /// C++0x [class.access.base]p5:
440 /// The access to a member is affected by the class in which the
441 /// member is named. This naming class is the class in which the
442 /// member name was looked up and found. [Note: this class can be
443 /// explicit, e.g., when a qualified-id is used, or implicit,
444 /// e.g., when a class member access operator (5.2.5) is used
445 /// (including cases where an implicit "this->" is added). If both
446 /// a class member access operator and a qualified-id are used to
447 /// name the member (as in p->T::m), the class naming the member
448 /// is the class named by the nested-name-specifier of the
449 /// qualified-id (that is, T). -- end note ]
450 ///
451 /// This is set by the lookup routines when they find results in a class.
453 return NamingClass;
454 }
455
456 /// Sets the 'naming class' for this lookup.
458 NamingClass = Record;
459 }
460
461 /// Returns the base object type associated with this lookup;
462 /// important for [class.protected]. Most lookups do not have an
463 /// associated base object.
465 return BaseObjectType;
466 }
467
468 /// Sets the base object type for this lookup.
470 BaseObjectType = T;
471 }
472
473 /// Add a declaration to these results with its natural access.
474 /// Does not test the acceptance criteria.
476 addDecl(D, D->getAccess());
477 }
478
479 /// Add a declaration to these results with the given access.
480 /// Does not test the acceptance criteria.
482 Decls.addDecl(D, AS);
483 ResultKind = LookupResultKind::Found;
484 }
485
486 /// Add all the declarations from another set of lookup
487 /// results.
489 Decls.append(Other.Decls.begin(), Other.Decls.end());
490 ResultKind = LookupResultKind::Found;
491 }
492
493 /// Determine whether no result was found because we could not
494 /// search into dependent base classes of the current instantiation.
497 }
498
499 /// Note that while no result was found in the current instantiation,
500 /// there were dependent base classes that could not be searched.
502 assert((ResultKind == LookupResultKind::NotFound ||
504 Decls.empty());
506 }
507
508 /// Determine whether the lookup result was shadowed by some other
509 /// declaration that lookup ignored.
510 bool isShadowed() const { return Shadowed; }
511
512 /// Note that we found and ignored a declaration while performing
513 /// lookup.
514 void setShadowed() { Shadowed = true; }
515
516 /// Resolves the result kind of the lookup, possibly hiding
517 /// decls.
518 ///
519 /// This should be called in any environment where lookup might
520 /// generate multiple lookup results.
521 void resolveKind();
522
523 /// Re-resolves the result kind of the lookup after a set of
524 /// removals has been performed.
526 if (Decls.empty()) {
528 ResultKind = LookupResultKind::NotFound;
529
530 if (Paths) {
531 deletePaths(Paths);
532 Paths = nullptr;
533 }
534 } else {
535 std::optional<LookupAmbiguityKind> SavedAK;
536 bool WasAmbiguous = false;
537 if (ResultKind == LookupResultKind::Ambiguous) {
538 SavedAK = Ambiguity;
539 WasAmbiguous = true;
540 }
541 ResultKind = LookupResultKind::Found;
542 resolveKind();
543
544 // If we didn't make the lookup unambiguous, restore the old
545 // ambiguity kind.
546 if (ResultKind == LookupResultKind::Ambiguous) {
547 (void)WasAmbiguous;
548 assert(WasAmbiguous);
549 Ambiguity = *SavedAK;
550 } else if (Paths) {
551 deletePaths(Paths);
552 Paths = nullptr;
553 }
554 }
555 }
556
557 template <class DeclClass>
558 DeclClass *getAsSingle() const {
560 return nullptr;
561 return dyn_cast<DeclClass>(getFoundDecl());
562 }
563
564 /// Fetch the unique decl found by this lookup. Asserts
565 /// that one was found.
566 ///
567 /// This is intended for users who have examined the result kind
568 /// and are certain that there is only one result.
571 "getFoundDecl called on non-unique result");
572 return (*begin())->getUnderlyingDecl();
573 }
574
575 /// Fetches a representative decl. Useful for lazy diagnostics.
577 assert(!Decls.empty() && "cannot get representative of empty set");
578 return *begin();
579 }
580
581 /// Asks if the result is a single tag decl.
582 bool isSingleTagDecl() const {
584 isa<TagDecl>(getFoundDecl());
585 }
586
587 /// Make these results show that the name was found in
588 /// base classes of different types.
589 ///
590 /// The given paths object is copied and invalidated.
592
593 /// Make these results show that the name was found in
594 /// distinct base classes of the same type.
595 ///
596 /// The given paths object is copied and invalidated.
598
599 /// Make these results show that the name was found in
600 /// different contexts and a tag decl was hidden by an ordinary
601 /// decl in a different context.
604 }
605
606 /// Clears out any current state.
607 LLVM_ATTRIBUTE_REINITIALIZES void clear() {
608 ResultKind = LookupResultKind::NotFound;
609 Decls.clear();
610 if (Paths) deletePaths(Paths);
611 Paths = nullptr;
612 NamingClass = nullptr;
613 Shadowed = false;
614 }
615
616 /// Clears out any current state and re-initializes for a
617 /// different kind of lookup.
619 clear();
620 LookupKind = Kind;
621 configure();
622 }
623
624 /// Change this lookup's redeclaration kind.
626 Redecl = (RK != RedeclarationKind::NotForRedeclaration);
627 ExternalRedecl = (RK == RedeclarationKind::ForExternalRedeclaration);
628 configure();
629 }
630
631 void dump();
632 void print(raw_ostream &);
633
634 /// Suppress the diagnostics that would normally fire because of this
635 /// lookup. This happens during (e.g.) redeclaration lookups.
637 DiagnoseAccess = false;
638 DiagnoseAmbiguous = false;
639 }
640
641 /// Suppress the diagnostics that would normally fire because of this
642 /// lookup due to access control violations.
643 void suppressAccessDiagnostics() { DiagnoseAccess = false; }
644
645 /// Determines whether this lookup is suppressing access control diagnostics.
646 bool isSuppressingAccessDiagnostics() const { return !DiagnoseAccess; }
647
648 /// Determines whether this lookup is suppressing ambiguous lookup
649 /// diagnostics.
650 bool isSuppressingAmbiguousDiagnostics() const { return !DiagnoseAmbiguous; }
651
652 /// Sets a 'context' source range.
654 NameContextRange = SR;
655 }
656
657 /// Gets the source range of the context of this name; for C++
658 /// qualified lookups, this is the source range of the scope
659 /// specifier.
661 return NameContextRange;
662 }
663
664 /// Gets the location of the identifier. This isn't always defined:
665 /// sometimes we're doing lookups on synthesized names.
667 return NameInfo.getLoc();
668 }
669
670 /// Get the Sema object that this lookup result is searching
671 /// with.
672 Sema &getSema() const { return *SemaPtr; }
673
674 /// A class for iterating through a result set and possibly
675 /// filtering out results. The results returned are possibly
676 /// sugared.
677 class Filter {
678 friend class LookupResult;
679
680 LookupResult &Results;
682 bool Changed = false;
683 bool CalledDone = false;
684
685 Filter(LookupResult &Results) : Results(Results), I(Results.begin()) {}
686
687 public:
689 : Results(F.Results), I(F.I), Changed(F.Changed),
690 CalledDone(F.CalledDone) {
691 F.CalledDone = true;
692 }
693
694 // The move assignment operator is defined as deleted pending
695 // further motivation.
696 Filter &operator=(Filter &&) = delete;
697
698 // The copy constrcutor and copy assignment operator is defined as deleted
699 // pending further motivation.
700 Filter(const Filter &) = delete;
701 Filter &operator=(const Filter &) = delete;
702
704 assert(CalledDone &&
705 "LookupResult::Filter destroyed without done() call");
706 }
707
708 bool hasNext() const {
709 return I != Results.end();
710 }
711
713 assert(I != Results.end() && "next() called on empty filter");
714 return *I++;
715 }
716
717 /// Restart the iteration.
718 void restart() {
719 I = Results.begin();
720 }
721
722 /// Erase the last element returned from this iterator.
723 void erase() {
724 Results.Decls.erase(--I);
725 Changed = true;
726 }
727
728 /// Replaces the current entry with the given one, preserving the
729 /// access bits.
731 Results.Decls.replace(I-1, D);
732 Changed = true;
733 }
734
735 /// Replaces the current entry with the given one.
737 Results.Decls.replace(I-1, D, AS);
738 Changed = true;
739 }
740
741 void done() {
742 assert(!CalledDone && "done() called twice");
743 CalledDone = true;
744
745 if (Changed)
746 Results.resolveKindAfterFilter();
747 }
748 };
749
750 /// Create a filter for this result set.
752 return Filter(*this);
753 }
754
755 void setFindLocalExtern(bool FindLocalExtern) {
756 if (FindLocalExtern)
758 else
759 IDNS &= ~Decl::IDNS_LocalExtern;
760 }
761
762private:
763 void diagnoseAccess() {
764 if (!isAmbiguous() && isClassLookup() &&
765 getSema().getLangOpts().AccessControl)
766 getSema().CheckLookupAccess(*this);
767 }
768
769 void diagnoseAmbiguous() {
770 if (isAmbiguous())
772 }
773
774 void setAmbiguous(LookupAmbiguityKind AK) {
775 ResultKind = LookupResultKind::Ambiguous;
776 Ambiguity = AK;
777 }
778
779 void addDeclsFromBasePaths(const CXXBasePaths &P);
780 void configure();
781
782 bool checkDebugAssumptions() const;
783
784 bool checkUnresolved() const {
785 for (iterator I = begin(), E = end(); I != E; ++I)
786 if (isa<UnresolvedUsingValueDecl>((*I)->getUnderlyingDecl()))
787 return true;
788 return false;
789 }
790
791 static void deletePaths(CXXBasePaths *);
792
793 // Results.
795 // ill-defined unless ambiguous. Still need to be initialized it will be
796 // copied/moved.
797 LookupAmbiguityKind Ambiguity = {};
798 UnresolvedSet<8> Decls;
799 CXXBasePaths *Paths = nullptr;
800 CXXRecordDecl *NamingClass = nullptr;
801 QualType BaseObjectType;
802
803 // Parameters.
804 Sema *SemaPtr;
805 DeclarationNameInfo NameInfo;
806 SourceRange NameContextRange;
807 Sema::LookupNameKind LookupKind;
808 unsigned IDNS = 0; // set by configure()
809
810 bool Redecl;
811 bool ExternalRedecl;
812
813 /// True if tag declarations should be hidden if non-tags
814 /// are present
815 bool HideTags = true;
816
817 bool DiagnoseAccess = false;
818 bool DiagnoseAmbiguous = false;
819
820 /// True if we should allow hidden declarations to be 'visible'.
821 bool AllowHidden = false;
822
823 /// True if the found declarations were shadowed by some other
824 /// declaration that we skipped. This only happens when \c LookupKind
825 /// is \c LookupRedeclarationWithLinkage.
826 bool Shadowed = false;
827
828 /// True if we're looking up a template-name.
829 bool TemplateNameLookup = false;
830};
831
832/// Consumes visible declarations found when searching for
833/// all visible names within a given scope or context.
834///
835/// This abstract class is meant to be subclassed by clients of \c
836/// Sema::LookupVisibleDecls(), each of which should override the \c
837/// FoundDecl() function to process declarations as they are found.
839public:
840 /// Destroys the visible declaration consumer.
841 virtual ~VisibleDeclConsumer();
842
843 /// Determine whether hidden declarations (from unimported
844 /// modules) should be given to this consumer. By default, they
845 /// are not included.
846 virtual bool includeHiddenDecls() const;
847
848 /// Invoked each time \p Sema::LookupVisibleDecls() finds a
849 /// declaration visible from the current scope or context.
850 ///
851 /// \param ND the declaration found.
852 ///
853 /// \param Hiding a declaration that hides the declaration \p ND,
854 /// or NULL if no such declaration exists.
855 ///
856 /// \param Ctx the original context from which the lookup started.
857 ///
858 /// \param InBaseClass whether this declaration was found in base
859 /// class of the context we searched.
860 virtual void FoundDecl(NamedDecl *ND, NamedDecl *Hiding, DeclContext *Ctx,
861 bool InBaseClass) = 0;
862
863 /// Callback to inform the client that Sema entered into a new context
864 /// to find a visible declaration.
865 //
866 /// \param Ctx the context which Sema entered.
867 virtual void EnteredContext(DeclContext *Ctx) {}
868};
869
870/// A class for storing results from argument-dependent lookup.
872private:
873 /// A map from canonical decls to the 'most recent' decl.
874 llvm::MapVector<NamedDecl*, NamedDecl*> Decls;
875
876 struct select_second {
877 NamedDecl *operator()(std::pair<NamedDecl*, NamedDecl*> P) const {
878 return P.second;
879 }
880 };
881
882public:
883 /// Adds a new ADL candidate to this map.
884 void insert(NamedDecl *D);
885
886 /// Removes any data associated with a given decl.
888 Decls.erase(cast<NamedDecl>(D->getCanonicalDecl()));
889 }
890
891 using iterator =
892 llvm::mapped_iterator<decltype(Decls)::iterator, select_second>;
893
894 iterator begin() { return iterator(Decls.begin(), select_second()); }
895 iterator end() { return iterator(Decls.end(), select_second()); }
896};
897
898} // namespace clang
899
900#endif // LLVM_CLANG_SEMA_LOOKUP_H
StringRef P
const Decl * D
enum clang::sema::@1840::IndirectLocalPathEntry::EntryKind Kind
Expr * E
Defines the C++ Decl subclasses, other than those for templates (found in DeclTemplate....
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified.
Defines the clang::LangOptions interface.
llvm::MachO::Record Record
Definition: MachO.h:31
RedeclarationKind
Specifies whether (or how) name lookup is being performed for a redeclaration (vs.
Definition: Redeclaration.h:18
@ NotForRedeclaration
The lookup is a reference to this name that is not for the purpose of redeclaring the name.
@ ForExternalRedeclaration
The lookup results will be used for redeclaration of a name with external linkage; non-visible lookup...
Defines the clang::SourceLocation class and associated facilities.
Defines various enumerations that describe declaration and type specifiers.
C Language Family Type Representation.
A class for storing results from argument-dependent lookup.
Definition: Lookup.h:871
iterator end()
Definition: Lookup.h:895
void insert(NamedDecl *D)
Adds a new ADL candidate to this map.
void erase(NamedDecl *D)
Removes any data associated with a given decl.
Definition: Lookup.h:887
iterator begin()
Definition: Lookup.h:894
llvm::mapped_iterator< decltype(Decls)::iterator, select_second > iterator
Definition: Lookup.h:892
BasePaths - Represents the set of paths from a derived class to one of its (direct or indirect) bases...
Represents a C++ struct/union/class.
Definition: DeclCXX.h:258
DeclContext - This is used only as base class of specific decl types that can act as declaration cont...
Definition: DeclBase.h:1449
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:86
@ IDNS_LocalExtern
This declaration is a function-local extern declaration of a variable or function.
Definition: DeclBase.h:175
The name of a declaration.
A class for iterating through a result set and possibly filtering out results.
Definition: Lookup.h:677
void replace(NamedDecl *D)
Replaces the current entry with the given one, preserving the access bits.
Definition: Lookup.h:730
void restart()
Restart the iteration.
Definition: Lookup.h:718
Filter & operator=(const Filter &)=delete
Filter & operator=(Filter &&)=delete
void erase()
Erase the last element returned from this iterator.
Definition: Lookup.h:723
void replace(NamedDecl *D, AccessSpecifier AS)
Replaces the current entry with the given one.
Definition: Lookup.h:736
bool hasNext() const
Definition: Lookup.h:708
Filter(const Filter &)=delete
NamedDecl * next()
Definition: Lookup.h:712
Represents the results of name lookup.
Definition: Lookup.h:147
void setLookupNameInfo(const DeclarationNameInfo &NameInfo)
Sets the name info to look up.
Definition: Lookup.h:260
void resolveKindAfterFilter()
Re-resolves the result kind of the lookup after a set of removals has been performed.
Definition: Lookup.h:525
void addAllDecls(const LookupResult &Other)
Add all the declarations from another set of lookup results.
Definition: Lookup.h:488
RedeclarationKind redeclarationKind() const
Definition: Lookup.h:290
bool wasNotFoundInCurrentInstantiation() const
Determine whether no result was found because we could not search into dependent base classes of the ...
Definition: Lookup.h:495
void setShadowed()
Note that we found and ignored a declaration while performing lookup.
Definition: Lookup.h:514
static bool isAvailableForLookup(Sema &SemaRef, NamedDecl *ND)
Determine whether this lookup is permitted to see the declaration.
bool isSuppressingAccessDiagnostics() const
Determines whether this lookup is suppressing access control diagnostics.
Definition: Lookup.h:646
LLVM_ATTRIBUTE_REINITIALIZES void clear()
Clears out any current state.
Definition: Lookup.h:607
LookupResult(TemporaryToken _, const LookupResult &Other)
Creates a temporary lookup result, initializing its core data using the information from another resu...
Definition: Lookup.h:186
SourceRange getContextRange() const
Gets the source range of the context of this name; for C++ qualified lookups, this is the source rang...
Definition: Lookup.h:660
void setTemplateNameLookup(bool TemplateName)
Sets whether this is a template-name lookup.
Definition: Lookup.h:318
void setFindLocalExtern(bool FindLocalExtern)
Definition: Lookup.h:755
bool isUnresolvableResult() const
Definition: Lookup.h:340
void setBaseObjectType(QualType T)
Sets the base object type for this lookup.
Definition: Lookup.h:469
void setAllowHidden(bool AH)
Specify whether hidden declarations are visible, e.g., for recovery reasons.
Definition: Lookup.h:298
DeclClass * getAsSingle() const
Definition: Lookup.h:558
void addDecl(NamedDecl *D, AccessSpecifier AS)
Add a declaration to these results with the given access.
Definition: Lookup.h:481
void setContextRange(SourceRange SR)
Sets a 'context' source range.
Definition: Lookup.h:653
static bool isAcceptable(Sema &SemaRef, NamedDecl *D, Sema::AcceptableKind Kind)
Definition: Lookup.h:376
void setAmbiguousQualifiedTagHiding()
Make these results show that the name was found in different contexts and a tag decl was hidden by an...
Definition: Lookup.h:602
bool isForExternalRedeclaration() const
True if this lookup is just looking for an existing declaration to link against a declaration with ex...
Definition: Lookup.h:286
void addDecl(NamedDecl *D)
Add a declaration to these results with its natural access.
Definition: Lookup.h:475
bool isTemplateNameLookup() const
Definition: Lookup.h:322
void setAmbiguousBaseSubobjects(CXXBasePaths &P)
Make these results show that the name was found in distinct base classes of the same type.
Definition: SemaLookup.cpp:667
bool isSingleTagDecl() const
Asks if the result is a single tag decl.
Definition: Lookup.h:582
void setLookupName(DeclarationName Name)
Sets the name to look up.
Definition: Lookup.h:270
bool empty() const
Return true if no decls were found.
Definition: Lookup.h:362
void resolveKind()
Resolves the result kind of the lookup, possibly hiding decls.
Definition: SemaLookup.cpp:488
void setRedeclarationKind(RedeclarationKind RK)
Change this lookup's redeclaration kind.
Definition: Lookup.h:625
bool isOverloadedResult() const
Determines if the results are overloaded.
Definition: Lookup.h:336
SourceLocation getNameLoc() const
Gets the location of the identifier.
Definition: Lookup.h:666
void setAmbiguousBaseSubobjectTypes(CXXBasePaths &P)
Make these results show that the name was found in base classes of different types.
Definition: SemaLookup.cpp:675
CXXBasePaths * getBasePaths() const
Return the base paths structure that's associated with these results, or null if none is.
Definition: Lookup.h:366
Filter makeFilter()
Create a filter for this result set.
Definition: Lookup.h:751
NamedDecl * getFoundDecl() const
Fetch the unique decl found by this lookup.
Definition: Lookup.h:569
void setHideTags(bool Hide)
Sets whether tag declarations should be hidden by non-tag declarations during resolution.
Definition: Lookup.h:311
bool isAmbiguous() const
Definition: Lookup.h:324
LookupResult & operator=(LookupResult &&Other)
Definition: Lookup.h:220
NamedDecl * getAcceptableDecl(NamedDecl *D) const
Retrieve the accepted (re)declaration of the given declaration, if there is one.
Definition: Lookup.h:408
bool isSingleResult() const
Determines if this names a single result which is not an unresolved value using decl.
Definition: Lookup.h:331
unsigned getIdentifierNamespace() const
Returns the identifier namespace mask for this lookup.
Definition: Lookup.h:426
CXXRecordDecl * getNamingClass() const
Returns the 'naming class' for this lookup, i.e.
Definition: Lookup.h:452
Sema::LookupNameKind getLookupKind() const
Gets the kind of lookup to perform.
Definition: Lookup.h:275
Sema & getSema() const
Get the Sema object that this lookup result is searching with.
Definition: Lookup.h:672
QualType getBaseObjectType() const
Returns the base object type associated with this lookup; important for [class.protected].
Definition: Lookup.h:464
LookupAmbiguityKind getAmbiguityKind() const
Definition: Lookup.h:349
LookupResult(const LookupResult &)=delete
void suppressAccessDiagnostics()
Suppress the diagnostics that would normally fire because of this lookup due to access control violat...
Definition: Lookup.h:643
LookupResult(Sema &SemaRef, DeclarationName Name, SourceLocation NameLoc, Sema::LookupNameKind LookupKind, RedeclarationKind Redecl=RedeclarationKind::NotForRedeclaration)
Definition: Lookup.h:171
LookupResult & operator=(const LookupResult &)=delete
const UnresolvedSetImpl & asUnresolvedSet() const
Definition: Lookup.h:354
UnresolvedSetImpl::iterator iterator
Definition: Lookup.h:154
void clear(Sema::LookupNameKind Kind)
Clears out any current state and re-initializes for a different kind of lookup.
Definition: Lookup.h:618
LookupResult(LookupResult &&Other)
Definition: Lookup.h:198
bool isClassLookup() const
Returns whether these results arose from performing a lookup into a class.
Definition: Lookup.h:432
bool isSuppressingAmbiguousDiagnostics() const
Determines whether this lookup is suppressing ambiguous lookup diagnostics.
Definition: Lookup.h:650
void setNamingClass(CXXRecordDecl *Record)
Sets the 'naming class' for this lookup.
Definition: Lookup.h:457
LookupResult(Sema &SemaRef, const DeclarationNameInfo &NameInfo, Sema::LookupNameKind LookupKind, RedeclarationKind Redecl=RedeclarationKind::NotForRedeclaration)
Definition: Lookup.h:156
NamedDecl * getRepresentativeDecl() const
Fetches a representative decl. Useful for lazy diagnostics.
Definition: Lookup.h:576
LookupResultKind getResultKind() const
Definition: Lookup.h:344
void print(raw_ostream &)
Definition: SemaLookup.cpp:683
static bool isReachable(Sema &SemaRef, NamedDecl *D)
TemporaryToken
A little identifier for flagging temporary lookup results.
Definition: Lookup.h:150
void suppressDiagnostics()
Suppress the diagnostics that would normally fire because of this lookup.
Definition: Lookup.h:636
bool isForRedeclaration() const
True if this lookup is just looking for an existing declaration.
Definition: Lookup.h:280
DeclarationName getLookupName() const
Gets the name to look up.
Definition: Lookup.h:265
bool isHiddenDeclarationVisible(NamedDecl *ND) const
Determine whether this lookup is permitted to see hidden declarations, such as those in modules that ...
Definition: Lookup.h:304
iterator end() const
Definition: Lookup.h:359
void setNotFoundInCurrentInstantiation()
Note that while no result was found in the current instantiation, there were dependent base classes t...
Definition: Lookup.h:501
static bool isVisible(Sema &SemaRef, NamedDecl *D)
Determine whether the given declaration is visible to the program.
iterator begin() const
Definition: Lookup.h:358
const DeclarationNameInfo & getLookupNameInfo() const
Gets the name info to look up.
Definition: Lookup.h:255
bool isShadowed() const
Determine whether the lookup result was shadowed by some other declaration that lookup ignored.
Definition: Lookup.h:510
This represents a decl that may have a name.
Definition: Decl.h:273
bool isExternallyDeclarable() const
Determine whether this declaration can be redeclared in a different translation unit.
Definition: Decl.h:438
A (possibly-)qualified type.
Definition: TypeBase.h:937
Sema - This implements semantic analysis and AST building for C.
Definition: Sema.h:850
LookupNameKind
Describes the kind of name lookup to perform.
Definition: Sema.h:9277
AcceptableKind
Definition: Sema.h:9269
void CheckLookupAccess(const LookupResult &R)
Checks access to all the declarations in the given result set.
void DiagnoseAmbiguousLookup(LookupResult &Result)
Produce a diagnostic describing the ambiguity that resulted from name lookup.
Encodes a location in the source.
A trivial tuple used to represent a source range.
Represents a C++ template name within the type system.
Definition: TemplateName.h:222
A set of unresolved declarations.
Definition: UnresolvedSet.h:62
UnresolvedSetIterator iterator
Definition: UnresolvedSet.h:80
void append(iterator I, iterator E)
void addDecl(NamedDecl *D)
Definition: UnresolvedSet.h:91
The iterator over UnresolvedSets.
Definition: UnresolvedSet.h:35
Consumes visible declarations found when searching for all visible names within a given scope or cont...
Definition: Lookup.h:838
virtual bool includeHiddenDecls() const
Determine whether hidden declarations (from unimported modules) should be given to this consumer.
virtual void EnteredContext(DeclContext *Ctx)
Callback to inform the client that Sema entered into a new context to find a visible declaration.
Definition: Lookup.h:867
virtual void FoundDecl(NamedDecl *ND, NamedDecl *Hiding, DeclContext *Ctx, bool InBaseClass)=0
Invoked each time Sema::LookupVisibleDecls() finds a declaration visible from the current scope or co...
virtual ~VisibleDeclConsumer()
Destroys the visible declaration consumer.
The JSON file list parser is used to communicate input to InstallAPI.
LookupResultKind
Definition: Lookup.h:39
@ Ambiguous
Name lookup results in an ambiguity; use getAmbiguityKind to figure out what kind of ambiguity we hav...
@ NotFound
No entity found met the criteria.
@ FoundOverloaded
Name lookup found a set of overloaded functions that met the criteria.
@ Found
Name lookup found a single declaration that met the criteria.
@ FoundUnresolvedValue
Name lookup found an unresolvable value declaration and cannot yet complete.
@ NotFoundInCurrentInstantiation
No entity found met the criteria within the current instantiation,, but there were dependent base cla...
AccessSpecifier
A C++ access specifier (public, private, protected), plus the special value "none" which means differ...
Definition: Specifiers.h:123
LookupAmbiguityKind
Definition: Lookup.h:67
@ AmbiguousBaseSubobjects
Name lookup results in an ambiguity because multiple nonstatic entities that meet the lookup criteria...
@ AmbiguousTagHiding
Name lookup results in an ambiguity because an entity with a tag name was hidden by an entity with an...
@ AmbiguousReferenceToPlaceholderVariable
Name lookup results in an ambiguity because multiple placeholder variables were found in the same sco...
@ AmbiguousReference
Name lookup results in an ambiguity because multiple definitions of entity that meet the lookup crite...
@ AmbiguousBaseSubobjectTypes
Name lookup results in an ambiguity because multiple entities that meet the lookup criteria were foun...
const FunctionProtoType * T
@ Other
Other implicit parameter.
DeclarationNameInfo - A collector data type for bundling together a DeclarationName and the correspon...
SourceLocation getLoc() const
getLoc - Returns the main location of the declaration name.
DeclarationName getName() const
getName - Returns the embedded declaration name.
void setName(DeclarationName N)
setName - Sets the embedded declaration name.