clang  7.0.0svn
SemaLookup.cpp
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1 //===--------------------- SemaLookup.cpp - Name Lookup ------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements name lookup for C, C++, Objective-C, and
11 // Objective-C++.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "clang/AST/ASTContext.h"
17 #include "clang/AST/Decl.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/DeclLookups.h"
20 #include "clang/AST/DeclObjC.h"
21 #include "clang/AST/DeclTemplate.h"
22 #include "clang/AST/Expr.h"
23 #include "clang/AST/ExprCXX.h"
24 #include "clang/Basic/Builtins.h"
26 #include "clang/Lex/HeaderSearch.h"
27 #include "clang/Lex/ModuleLoader.h"
28 #include "clang/Lex/Preprocessor.h"
29 #include "clang/Sema/DeclSpec.h"
30 #include "clang/Sema/Lookup.h"
31 #include "clang/Sema/Overload.h"
32 #include "clang/Sema/Scope.h"
33 #include "clang/Sema/ScopeInfo.h"
34 #include "clang/Sema/Sema.h"
38 #include "llvm/ADT/STLExtras.h"
39 #include "llvm/ADT/SmallPtrSet.h"
40 #include "llvm/ADT/TinyPtrVector.h"
41 #include "llvm/ADT/edit_distance.h"
42 #include "llvm/Support/ErrorHandling.h"
43 #include <algorithm>
44 #include <iterator>
45 #include <list>
46 #include <set>
47 #include <utility>
48 #include <vector>
49 
50 using namespace clang;
51 using namespace sema;
52 
53 namespace {
54  class UnqualUsingEntry {
55  const DeclContext *Nominated;
56  const DeclContext *CommonAncestor;
57 
58  public:
59  UnqualUsingEntry(const DeclContext *Nominated,
60  const DeclContext *CommonAncestor)
61  : Nominated(Nominated), CommonAncestor(CommonAncestor) {
62  }
63 
64  const DeclContext *getCommonAncestor() const {
65  return CommonAncestor;
66  }
67 
68  const DeclContext *getNominatedNamespace() const {
69  return Nominated;
70  }
71 
72  // Sort by the pointer value of the common ancestor.
73  struct Comparator {
74  bool operator()(const UnqualUsingEntry &L, const UnqualUsingEntry &R) {
75  return L.getCommonAncestor() < R.getCommonAncestor();
76  }
77 
78  bool operator()(const UnqualUsingEntry &E, const DeclContext *DC) {
79  return E.getCommonAncestor() < DC;
80  }
81 
82  bool operator()(const DeclContext *DC, const UnqualUsingEntry &E) {
83  return DC < E.getCommonAncestor();
84  }
85  };
86  };
87 
88  /// A collection of using directives, as used by C++ unqualified
89  /// lookup.
90  class UnqualUsingDirectiveSet {
91  Sema &SemaRef;
92 
93  typedef SmallVector<UnqualUsingEntry, 8> ListTy;
94 
95  ListTy list;
96  llvm::SmallPtrSet<DeclContext*, 8> visited;
97 
98  public:
99  UnqualUsingDirectiveSet(Sema &SemaRef) : SemaRef(SemaRef) {}
100 
101  void visitScopeChain(Scope *S, Scope *InnermostFileScope) {
102  // C++ [namespace.udir]p1:
103  // During unqualified name lookup, the names appear as if they
104  // were declared in the nearest enclosing namespace which contains
105  // both the using-directive and the nominated namespace.
106  DeclContext *InnermostFileDC = InnermostFileScope->getEntity();
107  assert(InnermostFileDC && InnermostFileDC->isFileContext());
108 
109  for (; S; S = S->getParent()) {
110  // C++ [namespace.udir]p1:
111  // A using-directive shall not appear in class scope, but may
112  // appear in namespace scope or in block scope.
113  DeclContext *Ctx = S->getEntity();
114  if (Ctx && Ctx->isFileContext()) {
115  visit(Ctx, Ctx);
116  } else if (!Ctx || Ctx->isFunctionOrMethod()) {
117  for (auto *I : S->using_directives())
118  if (SemaRef.isVisible(I))
119  visit(I, InnermostFileDC);
120  }
121  }
122  }
123 
124  // Visits a context and collect all of its using directives
125  // recursively. Treats all using directives as if they were
126  // declared in the context.
127  //
128  // A given context is only every visited once, so it is important
129  // that contexts be visited from the inside out in order to get
130  // the effective DCs right.
131  void visit(DeclContext *DC, DeclContext *EffectiveDC) {
132  if (!visited.insert(DC).second)
133  return;
134 
135  addUsingDirectives(DC, EffectiveDC);
136  }
137 
138  // Visits a using directive and collects all of its using
139  // directives recursively. Treats all using directives as if they
140  // were declared in the effective DC.
141  void visit(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) {
143  if (!visited.insert(NS).second)
144  return;
145 
146  addUsingDirective(UD, EffectiveDC);
147  addUsingDirectives(NS, EffectiveDC);
148  }
149 
150  // Adds all the using directives in a context (and those nominated
151  // by its using directives, transitively) as if they appeared in
152  // the given effective context.
153  void addUsingDirectives(DeclContext *DC, DeclContext *EffectiveDC) {
155  while (true) {
156  for (auto UD : DC->using_directives()) {
158  if (SemaRef.isVisible(UD) && visited.insert(NS).second) {
159  addUsingDirective(UD, EffectiveDC);
160  queue.push_back(NS);
161  }
162  }
163 
164  if (queue.empty())
165  return;
166 
167  DC = queue.pop_back_val();
168  }
169  }
170 
171  // Add a using directive as if it had been declared in the given
172  // context. This helps implement C++ [namespace.udir]p3:
173  // The using-directive is transitive: if a scope contains a
174  // using-directive that nominates a second namespace that itself
175  // contains using-directives, the effect is as if the
176  // using-directives from the second namespace also appeared in
177  // the first.
178  void addUsingDirective(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) {
179  // Find the common ancestor between the effective context and
180  // the nominated namespace.
181  DeclContext *Common = UD->getNominatedNamespace();
182  while (!Common->Encloses(EffectiveDC))
183  Common = Common->getParent();
184  Common = Common->getPrimaryContext();
185 
186  list.push_back(UnqualUsingEntry(UD->getNominatedNamespace(), Common));
187  }
188 
189  void done() {
190  llvm::sort(list.begin(), list.end(), UnqualUsingEntry::Comparator());
191  }
192 
193  typedef ListTy::const_iterator const_iterator;
194 
195  const_iterator begin() const { return list.begin(); }
196  const_iterator end() const { return list.end(); }
197 
198  llvm::iterator_range<const_iterator>
199  getNamespacesFor(DeclContext *DC) const {
200  return llvm::make_range(std::equal_range(begin(), end(),
201  DC->getPrimaryContext(),
202  UnqualUsingEntry::Comparator()));
203  }
204  };
205 } // end anonymous namespace
206 
207 // Retrieve the set of identifier namespaces that correspond to a
208 // specific kind of name lookup.
209 static inline unsigned getIDNS(Sema::LookupNameKind NameKind,
210  bool CPlusPlus,
211  bool Redeclaration) {
212  unsigned IDNS = 0;
213  switch (NameKind) {
218  IDNS = Decl::IDNS_Ordinary;
219  if (CPlusPlus) {
221  if (Redeclaration)
223  }
224  if (Redeclaration)
225  IDNS |= Decl::IDNS_LocalExtern;
226  break;
227 
229  // Operator lookup is its own crazy thing; it is not the same
230  // as (e.g.) looking up an operator name for redeclaration.
231  assert(!Redeclaration && "cannot do redeclaration operator lookup");
233  break;
234 
235  case Sema::LookupTagName:
236  if (CPlusPlus) {
237  IDNS = Decl::IDNS_Type;
238 
239  // When looking for a redeclaration of a tag name, we add:
240  // 1) TagFriend to find undeclared friend decls
241  // 2) Namespace because they can't "overload" with tag decls.
242  // 3) Tag because it includes class templates, which can't
243  // "overload" with tag decls.
244  if (Redeclaration)
246  } else {
247  IDNS = Decl::IDNS_Tag;
248  }
249  break;
250 
251  case Sema::LookupLabel:
252  IDNS = Decl::IDNS_Label;
253  break;
254 
256  IDNS = Decl::IDNS_Member;
257  if (CPlusPlus)
259  break;
260 
263  break;
264 
266  IDNS = Decl::IDNS_Namespace;
267  break;
268 
270  assert(Redeclaration && "should only be used for redecl lookup");
274  break;
275 
278  break;
279 
282  break;
283 
284  case Sema::LookupAnyName:
287  | Decl::IDNS_Type;
288  break;
289  }
290  return IDNS;
291 }
292 
293 void LookupResult::configure() {
294  IDNS = getIDNS(LookupKind, getSema().getLangOpts().CPlusPlus,
295  isForRedeclaration());
296 
297  // If we're looking for one of the allocation or deallocation
298  // operators, make sure that the implicitly-declared new and delete
299  // operators can be found.
300  switch (NameInfo.getName().getCXXOverloadedOperator()) {
301  case OO_New:
302  case OO_Delete:
303  case OO_Array_New:
304  case OO_Array_Delete:
305  getSema().DeclareGlobalNewDelete();
306  break;
307 
308  default:
309  break;
310  }
311 
312  // Compiler builtins are always visible, regardless of where they end
313  // up being declared.
314  if (IdentifierInfo *Id = NameInfo.getName().getAsIdentifierInfo()) {
315  if (unsigned BuiltinID = Id->getBuiltinID()) {
316  if (!getSema().Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
317  AllowHidden = true;
318  }
319  }
320 }
321 
322 bool LookupResult::sanity() const {
323  // This function is never called by NDEBUG builds.
324  assert(ResultKind != NotFound || Decls.size() == 0);
325  assert(ResultKind != Found || Decls.size() == 1);
326  assert(ResultKind != FoundOverloaded || Decls.size() > 1 ||
327  (Decls.size() == 1 &&
328  isa<FunctionTemplateDecl>((*begin())->getUnderlyingDecl())));
329  assert(ResultKind != FoundUnresolvedValue || sanityCheckUnresolved());
330  assert(ResultKind != Ambiguous || Decls.size() > 1 ||
331  (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects ||
332  Ambiguity == AmbiguousBaseSubobjectTypes)));
333  assert((Paths != nullptr) == (ResultKind == Ambiguous &&
334  (Ambiguity == AmbiguousBaseSubobjectTypes ||
335  Ambiguity == AmbiguousBaseSubobjects)));
336  return true;
337 }
338 
339 // Necessary because CXXBasePaths is not complete in Sema.h
340 void LookupResult::deletePaths(CXXBasePaths *Paths) {
341  delete Paths;
342 }
343 
344 /// Get a representative context for a declaration such that two declarations
345 /// will have the same context if they were found within the same scope.
347  // For function-local declarations, use that function as the context. This
348  // doesn't account for scopes within the function; the caller must deal with
349  // those.
351  if (DC->isFunctionOrMethod())
352  return DC;
353 
354  // Otherwise, look at the semantic context of the declaration. The
355  // declaration must have been found there.
356  return D->getDeclContext()->getRedeclContext();
357 }
358 
359 /// Determine whether \p D is a better lookup result than \p Existing,
360 /// given that they declare the same entity.
362  NamedDecl *D, NamedDecl *Existing) {
363  // When looking up redeclarations of a using declaration, prefer a using
364  // shadow declaration over any other declaration of the same entity.
365  if (Kind == Sema::LookupUsingDeclName && isa<UsingShadowDecl>(D) &&
366  !isa<UsingShadowDecl>(Existing))
367  return true;
368 
369  auto *DUnderlying = D->getUnderlyingDecl();
370  auto *EUnderlying = Existing->getUnderlyingDecl();
371 
372  // If they have different underlying declarations, prefer a typedef over the
373  // original type (this happens when two type declarations denote the same
374  // type), per a generous reading of C++ [dcl.typedef]p3 and p4. The typedef
375  // might carry additional semantic information, such as an alignment override.
376  // However, per C++ [dcl.typedef]p5, when looking up a tag name, prefer a tag
377  // declaration over a typedef.
378  if (DUnderlying->getCanonicalDecl() != EUnderlying->getCanonicalDecl()) {
379  assert(isa<TypeDecl>(DUnderlying) && isa<TypeDecl>(EUnderlying));
380  bool HaveTag = isa<TagDecl>(EUnderlying);
381  bool WantTag = Kind == Sema::LookupTagName;
382  return HaveTag != WantTag;
383  }
384 
385  // Pick the function with more default arguments.
386  // FIXME: In the presence of ambiguous default arguments, we should keep both,
387  // so we can diagnose the ambiguity if the default argument is needed.
388  // See C++ [over.match.best]p3.
389  if (auto *DFD = dyn_cast<FunctionDecl>(DUnderlying)) {
390  auto *EFD = cast<FunctionDecl>(EUnderlying);
391  unsigned DMin = DFD->getMinRequiredArguments();
392  unsigned EMin = EFD->getMinRequiredArguments();
393  // If D has more default arguments, it is preferred.
394  if (DMin != EMin)
395  return DMin < EMin;
396  // FIXME: When we track visibility for default function arguments, check
397  // that we pick the declaration with more visible default arguments.
398  }
399 
400  // Pick the template with more default template arguments.
401  if (auto *DTD = dyn_cast<TemplateDecl>(DUnderlying)) {
402  auto *ETD = cast<TemplateDecl>(EUnderlying);
403  unsigned DMin = DTD->getTemplateParameters()->getMinRequiredArguments();
404  unsigned EMin = ETD->getTemplateParameters()->getMinRequiredArguments();
405  // If D has more default arguments, it is preferred. Note that default
406  // arguments (and their visibility) is monotonically increasing across the
407  // redeclaration chain, so this is a quick proxy for "is more recent".
408  if (DMin != EMin)
409  return DMin < EMin;
410  // If D has more *visible* default arguments, it is preferred. Note, an
411  // earlier default argument being visible does not imply that a later
412  // default argument is visible, so we can't just check the first one.
413  for (unsigned I = DMin, N = DTD->getTemplateParameters()->size();
414  I != N; ++I) {
416  ETD->getTemplateParameters()->getParam(I)) &&
418  DTD->getTemplateParameters()->getParam(I)))
419  return true;
420  }
421  }
422 
423  // VarDecl can have incomplete array types, prefer the one with more complete
424  // array type.
425  if (VarDecl *DVD = dyn_cast<VarDecl>(DUnderlying)) {
426  VarDecl *EVD = cast<VarDecl>(EUnderlying);
427  if (EVD->getType()->isIncompleteType() &&
428  !DVD->getType()->isIncompleteType()) {
429  // Prefer the decl with a more complete type if visible.
430  return S.isVisible(DVD);
431  }
432  return false; // Avoid picking up a newer decl, just because it was newer.
433  }
434 
435  // For most kinds of declaration, it doesn't really matter which one we pick.
436  if (!isa<FunctionDecl>(DUnderlying) && !isa<VarDecl>(DUnderlying)) {
437  // If the existing declaration is hidden, prefer the new one. Otherwise,
438  // keep what we've got.
439  return !S.isVisible(Existing);
440  }
441 
442  // Pick the newer declaration; it might have a more precise type.
443  for (Decl *Prev = DUnderlying->getPreviousDecl(); Prev;
444  Prev = Prev->getPreviousDecl())
445  if (Prev == EUnderlying)
446  return true;
447  return false;
448 }
449 
450 /// Determine whether \p D can hide a tag declaration.
451 static bool canHideTag(NamedDecl *D) {
452  // C++ [basic.scope.declarative]p4:
453  // Given a set of declarations in a single declarative region [...]
454  // exactly one declaration shall declare a class name or enumeration name
455  // that is not a typedef name and the other declarations shall all refer to
456  // the same variable, non-static data member, or enumerator, or all refer
457  // to functions and function templates; in this case the class name or
458  // enumeration name is hidden.
459  // C++ [basic.scope.hiding]p2:
460  // A class name or enumeration name can be hidden by the name of a
461  // variable, data member, function, or enumerator declared in the same
462  // scope.
463  // An UnresolvedUsingValueDecl always instantiates to one of these.
464  D = D->getUnderlyingDecl();
465  return isa<VarDecl>(D) || isa<EnumConstantDecl>(D) || isa<FunctionDecl>(D) ||
466  isa<FunctionTemplateDecl>(D) || isa<FieldDecl>(D) ||
467  isa<UnresolvedUsingValueDecl>(D);
468 }
469 
470 /// Resolves the result kind of this lookup.
472  unsigned N = Decls.size();
473 
474  // Fast case: no possible ambiguity.
475  if (N == 0) {
476  assert(ResultKind == NotFound ||
477  ResultKind == NotFoundInCurrentInstantiation);
478  return;
479  }
480 
481  // If there's a single decl, we need to examine it to decide what
482  // kind of lookup this is.
483  if (N == 1) {
484  NamedDecl *D = (*Decls.begin())->getUnderlyingDecl();
485  if (isa<FunctionTemplateDecl>(D))
486  ResultKind = FoundOverloaded;
487  else if (isa<UnresolvedUsingValueDecl>(D))
488  ResultKind = FoundUnresolvedValue;
489  return;
490  }
491 
492  // Don't do any extra resolution if we've already resolved as ambiguous.
493  if (ResultKind == Ambiguous) return;
494 
495  llvm::SmallDenseMap<NamedDecl*, unsigned, 16> Unique;
496  llvm::SmallDenseMap<QualType, unsigned, 16> UniqueTypes;
497 
498  bool Ambiguous = false;
499  bool HasTag = false, HasFunction = false;
500  bool HasFunctionTemplate = false, HasUnresolved = false;
501  NamedDecl *HasNonFunction = nullptr;
502 
503  llvm::SmallVector<NamedDecl*, 4> EquivalentNonFunctions;
504 
505  unsigned UniqueTagIndex = 0;
506 
507  unsigned I = 0;
508  while (I < N) {
509  NamedDecl *D = Decls[I]->getUnderlyingDecl();
510  D = cast<NamedDecl>(D->getCanonicalDecl());
511 
512  // Ignore an invalid declaration unless it's the only one left.
513  if (D->isInvalidDecl() && !(I == 0 && N == 1)) {
514  Decls[I] = Decls[--N];
515  continue;
516  }
517 
518  llvm::Optional<unsigned> ExistingI;
519 
520  // Redeclarations of types via typedef can occur both within a scope
521  // and, through using declarations and directives, across scopes. There is
522  // no ambiguity if they all refer to the same type, so unique based on the
523  // canonical type.
524  if (TypeDecl *TD = dyn_cast<TypeDecl>(D)) {
525  QualType T = getSema().Context.getTypeDeclType(TD);
526  auto UniqueResult = UniqueTypes.insert(
527  std::make_pair(getSema().Context.getCanonicalType(T), I));
528  if (!UniqueResult.second) {
529  // The type is not unique.
530  ExistingI = UniqueResult.first->second;
531  }
532  }
533 
534  // For non-type declarations, check for a prior lookup result naming this
535  // canonical declaration.
536  if (!ExistingI) {
537  auto UniqueResult = Unique.insert(std::make_pair(D, I));
538  if (!UniqueResult.second) {
539  // We've seen this entity before.
540  ExistingI = UniqueResult.first->second;
541  }
542  }
543 
544  if (ExistingI) {
545  // This is not a unique lookup result. Pick one of the results and
546  // discard the other.
547  if (isPreferredLookupResult(getSema(), getLookupKind(), Decls[I],
548  Decls[*ExistingI]))
549  Decls[*ExistingI] = Decls[I];
550  Decls[I] = Decls[--N];
551  continue;
552  }
553 
554  // Otherwise, do some decl type analysis and then continue.
555 
556  if (isa<UnresolvedUsingValueDecl>(D)) {
557  HasUnresolved = true;
558  } else if (isa<TagDecl>(D)) {
559  if (HasTag)
560  Ambiguous = true;
561  UniqueTagIndex = I;
562  HasTag = true;
563  } else if (isa<FunctionTemplateDecl>(D)) {
564  HasFunction = true;
565  HasFunctionTemplate = true;
566  } else if (isa<FunctionDecl>(D)) {
567  HasFunction = true;
568  } else {
569  if (HasNonFunction) {
570  // If we're about to create an ambiguity between two declarations that
571  // are equivalent, but one is an internal linkage declaration from one
572  // module and the other is an internal linkage declaration from another
573  // module, just skip it.
574  if (getSema().isEquivalentInternalLinkageDeclaration(HasNonFunction,
575  D)) {
576  EquivalentNonFunctions.push_back(D);
577  Decls[I] = Decls[--N];
578  continue;
579  }
580 
581  Ambiguous = true;
582  }
583  HasNonFunction = D;
584  }
585  I++;
586  }
587 
588  // C++ [basic.scope.hiding]p2:
589  // A class name or enumeration name can be hidden by the name of
590  // an object, function, or enumerator declared in the same
591  // scope. If a class or enumeration name and an object, function,
592  // or enumerator are declared in the same scope (in any order)
593  // with the same name, the class or enumeration name is hidden
594  // wherever the object, function, or enumerator name is visible.
595  // But it's still an error if there are distinct tag types found,
596  // even if they're not visible. (ref?)
597  if (N > 1 && HideTags && HasTag && !Ambiguous &&
598  (HasFunction || HasNonFunction || HasUnresolved)) {
599  NamedDecl *OtherDecl = Decls[UniqueTagIndex ? 0 : N - 1];
600  if (isa<TagDecl>(Decls[UniqueTagIndex]->getUnderlyingDecl()) &&
601  getContextForScopeMatching(Decls[UniqueTagIndex])->Equals(
602  getContextForScopeMatching(OtherDecl)) &&
603  canHideTag(OtherDecl))
604  Decls[UniqueTagIndex] = Decls[--N];
605  else
606  Ambiguous = true;
607  }
608 
609  // FIXME: This diagnostic should really be delayed until we're done with
610  // the lookup result, in case the ambiguity is resolved by the caller.
611  if (!EquivalentNonFunctions.empty() && !Ambiguous)
612  getSema().diagnoseEquivalentInternalLinkageDeclarations(
613  getNameLoc(), HasNonFunction, EquivalentNonFunctions);
614 
615  Decls.set_size(N);
616 
617  if (HasNonFunction && (HasFunction || HasUnresolved))
618  Ambiguous = true;
619 
620  if (Ambiguous)
621  setAmbiguous(LookupResult::AmbiguousReference);
622  else if (HasUnresolved)
624  else if (N > 1 || HasFunctionTemplate)
625  ResultKind = LookupResult::FoundOverloaded;
626  else
627  ResultKind = LookupResult::Found;
628 }
629 
630 void LookupResult::addDeclsFromBasePaths(const CXXBasePaths &P) {
632  for (I = P.begin(), E = P.end(); I != E; ++I)
633  for (DeclContext::lookup_iterator DI = I->Decls.begin(),
634  DE = I->Decls.end(); DI != DE; ++DI)
635  addDecl(*DI);
636 }
637 
639  Paths = new CXXBasePaths;
640  Paths->swap(P);
641  addDeclsFromBasePaths(*Paths);
642  resolveKind();
643  setAmbiguous(AmbiguousBaseSubobjects);
644 }
645 
647  Paths = new CXXBasePaths;
648  Paths->swap(P);
649  addDeclsFromBasePaths(*Paths);
650  resolveKind();
651  setAmbiguous(AmbiguousBaseSubobjectTypes);
652 }
653 
654 void LookupResult::print(raw_ostream &Out) {
655  Out << Decls.size() << " result(s)";
656  if (isAmbiguous()) Out << ", ambiguous";
657  if (Paths) Out << ", base paths present";
658 
659  for (iterator I = begin(), E = end(); I != E; ++I) {
660  Out << "\n";
661  (*I)->print(Out, 2);
662  }
663 }
664 
665 LLVM_DUMP_METHOD void LookupResult::dump() {
666  llvm::errs() << "lookup results for " << getLookupName().getAsString()
667  << ":\n";
668  for (NamedDecl *D : *this)
669  D->dump();
670 }
671 
672 /// Lookup a builtin function, when name lookup would otherwise
673 /// fail.
674 static bool LookupBuiltin(Sema &S, LookupResult &R) {
675  Sema::LookupNameKind NameKind = R.getLookupKind();
676 
677  // If we didn't find a use of this identifier, and if the identifier
678  // corresponds to a compiler builtin, create the decl object for the builtin
679  // now, injecting it into translation unit scope, and return it.
680  if (NameKind == Sema::LookupOrdinaryName ||
683  if (II) {
684  if (S.getLangOpts().CPlusPlus && NameKind == Sema::LookupOrdinaryName) {
685  if (II == S.getASTContext().getMakeIntegerSeqName()) {
687  return true;
688  } else if (II == S.getASTContext().getTypePackElementName()) {
690  return true;
691  }
692  }
693 
694  // If this is a builtin on this (or all) targets, create the decl.
695  if (unsigned BuiltinID = II->getBuiltinID()) {
696  // In C++ and OpenCL (spec v1.2 s6.9.f), we don't have any predefined
697  // library functions like 'malloc'. Instead, we'll just error.
698  if ((S.getLangOpts().CPlusPlus || S.getLangOpts().OpenCL) &&
700  return false;
701 
703  BuiltinID, S.TUScope,
704  R.isForRedeclaration(),
705  R.getNameLoc())) {
706  R.addDecl(D);
707  return true;
708  }
709  }
710  }
711  }
712 
713  return false;
714 }
715 
716 /// Determine whether we can declare a special member function within
717 /// the class at this point.
719  // We need to have a definition for the class.
720  if (!Class->getDefinition() || Class->isDependentContext())
721  return false;
722 
723  // We can't be in the middle of defining the class.
724  return !Class->isBeingDefined();
725 }
726 
729  return;
730 
731  // If the default constructor has not yet been declared, do so now.
732  if (Class->needsImplicitDefaultConstructor())
733  DeclareImplicitDefaultConstructor(Class);
734 
735  // If the copy constructor has not yet been declared, do so now.
736  if (Class->needsImplicitCopyConstructor())
737  DeclareImplicitCopyConstructor(Class);
738 
739  // If the copy assignment operator has not yet been declared, do so now.
740  if (Class->needsImplicitCopyAssignment())
741  DeclareImplicitCopyAssignment(Class);
742 
743  if (getLangOpts().CPlusPlus11) {
744  // If the move constructor has not yet been declared, do so now.
745  if (Class->needsImplicitMoveConstructor())
746  DeclareImplicitMoveConstructor(Class);
747 
748  // If the move assignment operator has not yet been declared, do so now.
749  if (Class->needsImplicitMoveAssignment())
750  DeclareImplicitMoveAssignment(Class);
751  }
752 
753  // If the destructor has not yet been declared, do so now.
754  if (Class->needsImplicitDestructor())
755  DeclareImplicitDestructor(Class);
756 }
757 
758 /// Determine whether this is the name of an implicitly-declared
759 /// special member function.
761  switch (Name.getNameKind()) {
764  return true;
765 
767  return Name.getCXXOverloadedOperator() == OO_Equal;
768 
769  default:
770  break;
771  }
772 
773  return false;
774 }
775 
776 /// If there are any implicit member functions with the given name
777 /// that need to be declared in the given declaration context, do so.
779  DeclarationName Name,
780  SourceLocation Loc,
781  const DeclContext *DC) {
782  if (!DC)
783  return;
784 
785  switch (Name.getNameKind()) {
787  if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
788  if (Record->getDefinition() && CanDeclareSpecialMemberFunction(Record)) {
789  CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record);
790  if (Record->needsImplicitDefaultConstructor())
792  if (Record->needsImplicitCopyConstructor())
794  if (S.getLangOpts().CPlusPlus11 &&
795  Record->needsImplicitMoveConstructor())
797  }
798  break;
799 
801  if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
802  if (Record->getDefinition() && Record->needsImplicitDestructor() &&
804  S.DeclareImplicitDestructor(const_cast<CXXRecordDecl *>(Record));
805  break;
806 
808  if (Name.getCXXOverloadedOperator() != OO_Equal)
809  break;
810 
811  if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) {
812  if (Record->getDefinition() && CanDeclareSpecialMemberFunction(Record)) {
813  CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record);
814  if (Record->needsImplicitCopyAssignment())
816  if (S.getLangOpts().CPlusPlus11 &&
817  Record->needsImplicitMoveAssignment())
819  }
820  }
821  break;
822 
825  break;
826 
827  default:
828  break;
829  }
830 }
831 
832 // Adds all qualifying matches for a name within a decl context to the
833 // given lookup result. Returns true if any matches were found.
834 static bool LookupDirect(Sema &S, LookupResult &R, const DeclContext *DC) {
835  bool Found = false;
836 
837  // Lazily declare C++ special member functions.
838  if (S.getLangOpts().CPlusPlus)
840  DC);
841 
842  // Perform lookup into this declaration context.
844  for (NamedDecl *D : DR) {
845  if ((D = R.getAcceptableDecl(D))) {
846  R.addDecl(D);
847  Found = true;
848  }
849  }
850 
851  if (!Found && DC->isTranslationUnit() && LookupBuiltin(S, R))
852  return true;
853 
854  if (R.getLookupName().getNameKind()
857  !isa<CXXRecordDecl>(DC))
858  return Found;
859 
860  // C++ [temp.mem]p6:
861  // A specialization of a conversion function template is not found by
862  // name lookup. Instead, any conversion function templates visible in the
863  // context of the use are considered. [...]
864  const CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
865  if (!Record->isCompleteDefinition())
866  return Found;
867 
868  // For conversion operators, 'operator auto' should only match
869  // 'operator auto'. Since 'auto' is not a type, it shouldn't be considered
870  // as a candidate for template substitution.
871  auto *ContainedDeducedType =
873  if (R.getLookupName().getNameKind() ==
875  ContainedDeducedType && ContainedDeducedType->isUndeducedType())
876  return Found;
877 
879  UEnd = Record->conversion_end(); U != UEnd; ++U) {
880  FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(*U);
881  if (!ConvTemplate)
882  continue;
883 
884  // When we're performing lookup for the purposes of redeclaration, just
885  // add the conversion function template. When we deduce template
886  // arguments for specializations, we'll end up unifying the return
887  // type of the new declaration with the type of the function template.
888  if (R.isForRedeclaration()) {
889  R.addDecl(ConvTemplate);
890  Found = true;
891  continue;
892  }
893 
894  // C++ [temp.mem]p6:
895  // [...] For each such operator, if argument deduction succeeds
896  // (14.9.2.3), the resulting specialization is used as if found by
897  // name lookup.
898  //
899  // When referencing a conversion function for any purpose other than
900  // a redeclaration (such that we'll be building an expression with the
901  // result), perform template argument deduction and place the
902  // specialization into the result set. We do this to avoid forcing all
903  // callers to perform special deduction for conversion functions.
905  FunctionDecl *Specialization = nullptr;
906 
907  const FunctionProtoType *ConvProto
908  = ConvTemplate->getTemplatedDecl()->getType()->getAs<FunctionProtoType>();
909  assert(ConvProto && "Nonsensical conversion function template type");
910 
911  // Compute the type of the function that we would expect the conversion
912  // function to have, if it were to match the name given.
913  // FIXME: Calling convention!
915  EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC_C);
916  EPI.ExceptionSpec = EST_None;
917  QualType ExpectedType
919  None, EPI);
920 
921  // Perform template argument deduction against the type that we would
922  // expect the function to have.
923  if (R.getSema().DeduceTemplateArguments(ConvTemplate, nullptr, ExpectedType,
924  Specialization, Info)
925  == Sema::TDK_Success) {
926  R.addDecl(Specialization);
927  Found = true;
928  }
929  }
930 
931  return Found;
932 }
933 
934 // Performs C++ unqualified lookup into the given file context.
935 static bool
937  DeclContext *NS, UnqualUsingDirectiveSet &UDirs) {
938 
939  assert(NS && NS->isFileContext() && "CppNamespaceLookup() requires namespace!");
940 
941  // Perform direct name lookup into the LookupCtx.
942  bool Found = LookupDirect(S, R, NS);
943 
944  // Perform direct name lookup into the namespaces nominated by the
945  // using directives whose common ancestor is this namespace.
946  for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(NS))
947  if (LookupDirect(S, R, UUE.getNominatedNamespace()))
948  Found = true;
949 
950  R.resolveKind();
951 
952  return Found;
953 }
954 
956  if (DeclContext *Ctx = S->getEntity())
957  return Ctx->isFileContext();
958  return false;
959 }
960 
961 // Find the next outer declaration context from this scope. This
962 // routine actually returns the semantic outer context, which may
963 // differ from the lexical context (encoded directly in the Scope
964 // stack) when we are parsing a member of a class template. In this
965 // case, the second element of the pair will be true, to indicate that
966 // name lookup should continue searching in this semantic context when
967 // it leaves the current template parameter scope.
968 static std::pair<DeclContext *, bool> findOuterContext(Scope *S) {
969  DeclContext *DC = S->getEntity();
970  DeclContext *Lexical = nullptr;
971  for (Scope *OuterS = S->getParent(); OuterS;
972  OuterS = OuterS->getParent()) {
973  if (OuterS->getEntity()) {
974  Lexical = OuterS->getEntity();
975  break;
976  }
977  }
978 
979  // C++ [temp.local]p8:
980  // In the definition of a member of a class template that appears
981  // outside of the namespace containing the class template
982  // definition, the name of a template-parameter hides the name of
983  // a member of this namespace.
984  //
985  // Example:
986  //
987  // namespace N {
988  // class C { };
989  //
990  // template<class T> class B {
991  // void f(T);
992  // };
993  // }
994  //
995  // template<class C> void N::B<C>::f(C) {
996  // C b; // C is the template parameter, not N::C
997  // }
998  //
999  // In this example, the lexical context we return is the
1000  // TranslationUnit, while the semantic context is the namespace N.
1001  if (!Lexical || !DC || !S->getParent() ||
1003  return std::make_pair(Lexical, false);
1004 
1005  // Find the outermost template parameter scope.
1006  // For the example, this is the scope for the template parameters of
1007  // template<class C>.
1008  Scope *OutermostTemplateScope = S->getParent();
1009  while (OutermostTemplateScope->getParent() &&
1010  OutermostTemplateScope->getParent()->isTemplateParamScope())
1011  OutermostTemplateScope = OutermostTemplateScope->getParent();
1012 
1013  // Find the namespace context in which the original scope occurs. In
1014  // the example, this is namespace N.
1015  DeclContext *Semantic = DC;
1016  while (!Semantic->isFileContext())
1017  Semantic = Semantic->getParent();
1018 
1019  // Find the declaration context just outside of the template
1020  // parameter scope. This is the context in which the template is
1021  // being lexically declaration (a namespace context). In the
1022  // example, this is the global scope.
1023  if (Lexical->isFileContext() && !Lexical->Equals(Semantic) &&
1024  Lexical->Encloses(Semantic))
1025  return std::make_pair(Semantic, true);
1026 
1027  return std::make_pair(Lexical, false);
1028 }
1029 
1030 namespace {
1031 /// An RAII object to specify that we want to find block scope extern
1032 /// declarations.
1033 struct FindLocalExternScope {
1034  FindLocalExternScope(LookupResult &R)
1035  : R(R), OldFindLocalExtern(R.getIdentifierNamespace() &
1039  }
1040  void restore() {
1041  R.setFindLocalExtern(OldFindLocalExtern);
1042  }
1043  ~FindLocalExternScope() {
1044  restore();
1045  }
1046  LookupResult &R;
1047  bool OldFindLocalExtern;
1048 };
1049 } // end anonymous namespace
1050 
1051 bool Sema::CppLookupName(LookupResult &R, Scope *S) {
1052  assert(getLangOpts().CPlusPlus && "Can perform only C++ lookup");
1053 
1054  DeclarationName Name = R.getLookupName();
1055  Sema::LookupNameKind NameKind = R.getLookupKind();
1056 
1057  // If this is the name of an implicitly-declared special member function,
1058  // go through the scope stack to implicitly declare
1060  for (Scope *PreS = S; PreS; PreS = PreS->getParent())
1061  if (DeclContext *DC = PreS->getEntity())
1062  DeclareImplicitMemberFunctionsWithName(*this, Name, R.getNameLoc(), DC);
1063  }
1064 
1065  // Implicitly declare member functions with the name we're looking for, if in
1066  // fact we are in a scope where it matters.
1067 
1068  Scope *Initial = S;
1070  I = IdResolver.begin(Name),
1071  IEnd = IdResolver.end();
1072 
1073  // First we lookup local scope.
1074  // We don't consider using-directives, as per 7.3.4.p1 [namespace.udir]
1075  // ...During unqualified name lookup (3.4.1), the names appear as if
1076  // they were declared in the nearest enclosing namespace which contains
1077  // both the using-directive and the nominated namespace.
1078  // [Note: in this context, "contains" means "contains directly or
1079  // indirectly".
1080  //
1081  // For example:
1082  // namespace A { int i; }
1083  // void foo() {
1084  // int i;
1085  // {
1086  // using namespace A;
1087  // ++i; // finds local 'i', A::i appears at global scope
1088  // }
1089  // }
1090  //
1091  UnqualUsingDirectiveSet UDirs(*this);
1092  bool VisitedUsingDirectives = false;
1093  bool LeftStartingScope = false;
1094  DeclContext *OutsideOfTemplateParamDC = nullptr;
1095 
1096  // When performing a scope lookup, we want to find local extern decls.
1097  FindLocalExternScope FindLocals(R);
1098 
1099  for (; S && !isNamespaceOrTranslationUnitScope(S); S = S->getParent()) {
1100  DeclContext *Ctx = S->getEntity();
1101  bool SearchNamespaceScope = true;
1102  // Check whether the IdResolver has anything in this scope.
1103  for (; I != IEnd && S->isDeclScope(*I); ++I) {
1104  if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
1105  if (NameKind == LookupRedeclarationWithLinkage &&
1106  !(*I)->isTemplateParameter()) {
1107  // If it's a template parameter, we still find it, so we can diagnose
1108  // the invalid redeclaration.
1109 
1110  // Determine whether this (or a previous) declaration is
1111  // out-of-scope.
1112  if (!LeftStartingScope && !Initial->isDeclScope(*I))
1113  LeftStartingScope = true;
1114 
1115  // If we found something outside of our starting scope that
1116  // does not have linkage, skip it.
1117  if (LeftStartingScope && !((*I)->hasLinkage())) {
1118  R.setShadowed();
1119  continue;
1120  }
1121  } else {
1122  // We found something in this scope, we should not look at the
1123  // namespace scope
1124  SearchNamespaceScope = false;
1125  }
1126  R.addDecl(ND);
1127  }
1128  }
1129  if (!SearchNamespaceScope) {
1130  R.resolveKind();
1131  if (S->isClassScope())
1132  if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(Ctx))
1133  R.setNamingClass(Record);
1134  return true;
1135  }
1136 
1137  if (NameKind == LookupLocalFriendName && !S->isClassScope()) {
1138  // C++11 [class.friend]p11:
1139  // If a friend declaration appears in a local class and the name
1140  // specified is an unqualified name, a prior declaration is
1141  // looked up without considering scopes that are outside the
1142  // innermost enclosing non-class scope.
1143  return false;
1144  }
1145 
1146  if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
1147  S->getParent() && !S->getParent()->isTemplateParamScope()) {
1148  // We've just searched the last template parameter scope and
1149  // found nothing, so look into the contexts between the
1150  // lexical and semantic declaration contexts returned by
1151  // findOuterContext(). This implements the name lookup behavior
1152  // of C++ [temp.local]p8.
1153  Ctx = OutsideOfTemplateParamDC;
1154  OutsideOfTemplateParamDC = nullptr;
1155  }
1156 
1157  if (Ctx) {
1158  DeclContext *OuterCtx;
1159  bool SearchAfterTemplateScope;
1160  std::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
1161  if (SearchAfterTemplateScope)
1162  OutsideOfTemplateParamDC = OuterCtx;
1163 
1164  for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
1165  // We do not directly look into transparent contexts, since
1166  // those entities will be found in the nearest enclosing
1167  // non-transparent context.
1168  if (Ctx->isTransparentContext())
1169  continue;
1170 
1171  // We do not look directly into function or method contexts,
1172  // since all of the local variables and parameters of the
1173  // function/method are present within the Scope.
1174  if (Ctx->isFunctionOrMethod()) {
1175  // If we have an Objective-C instance method, look for ivars
1176  // in the corresponding interface.
1177  if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
1178  if (Method->isInstanceMethod() && Name.getAsIdentifierInfo())
1179  if (ObjCInterfaceDecl *Class = Method->getClassInterface()) {
1180  ObjCInterfaceDecl *ClassDeclared;
1181  if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(
1182  Name.getAsIdentifierInfo(),
1183  ClassDeclared)) {
1184  if (NamedDecl *ND = R.getAcceptableDecl(Ivar)) {
1185  R.addDecl(ND);
1186  R.resolveKind();
1187  return true;
1188  }
1189  }
1190  }
1191  }
1192 
1193  continue;
1194  }
1195 
1196  // If this is a file context, we need to perform unqualified name
1197  // lookup considering using directives.
1198  if (Ctx->isFileContext()) {
1199  // If we haven't handled using directives yet, do so now.
1200  if (!VisitedUsingDirectives) {
1201  // Add using directives from this context up to the top level.
1202  for (DeclContext *UCtx = Ctx; UCtx; UCtx = UCtx->getParent()) {
1203  if (UCtx->isTransparentContext())
1204  continue;
1205 
1206  UDirs.visit(UCtx, UCtx);
1207  }
1208 
1209  // Find the innermost file scope, so we can add using directives
1210  // from local scopes.
1211  Scope *InnermostFileScope = S;
1212  while (InnermostFileScope &&
1213  !isNamespaceOrTranslationUnitScope(InnermostFileScope))
1214  InnermostFileScope = InnermostFileScope->getParent();
1215  UDirs.visitScopeChain(Initial, InnermostFileScope);
1216 
1217  UDirs.done();
1218 
1219  VisitedUsingDirectives = true;
1220  }
1221 
1222  if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs)) {
1223  R.resolveKind();
1224  return true;
1225  }
1226 
1227  continue;
1228  }
1229 
1230  // Perform qualified name lookup into this context.
1231  // FIXME: In some cases, we know that every name that could be found by
1232  // this qualified name lookup will also be on the identifier chain. For
1233  // example, inside a class without any base classes, we never need to
1234  // perform qualified lookup because all of the members are on top of the
1235  // identifier chain.
1236  if (LookupQualifiedName(R, Ctx, /*InUnqualifiedLookup=*/true))
1237  return true;
1238  }
1239  }
1240  }
1241 
1242  // Stop if we ran out of scopes.
1243  // FIXME: This really, really shouldn't be happening.
1244  if (!S) return false;
1245 
1246  // If we are looking for members, no need to look into global/namespace scope.
1247  if (NameKind == LookupMemberName)
1248  return false;
1249 
1250  // Collect UsingDirectiveDecls in all scopes, and recursively all
1251  // nominated namespaces by those using-directives.
1252  //
1253  // FIXME: Cache this sorted list in Scope structure, and DeclContext, so we
1254  // don't build it for each lookup!
1255  if (!VisitedUsingDirectives) {
1256  UDirs.visitScopeChain(Initial, S);
1257  UDirs.done();
1258  }
1259 
1260  // If we're not performing redeclaration lookup, do not look for local
1261  // extern declarations outside of a function scope.
1262  if (!R.isForRedeclaration())
1263  FindLocals.restore();
1264 
1265  // Lookup namespace scope, and global scope.
1266  // Unqualified name lookup in C++ requires looking into scopes
1267  // that aren't strictly lexical, and therefore we walk through the
1268  // context as well as walking through the scopes.
1269  for (; S; S = S->getParent()) {
1270  // Check whether the IdResolver has anything in this scope.
1271  bool Found = false;
1272  for (; I != IEnd && S->isDeclScope(*I); ++I) {
1273  if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
1274  // We found something. Look for anything else in our scope
1275  // with this same name and in an acceptable identifier
1276  // namespace, so that we can construct an overload set if we
1277  // need to.
1278  Found = true;
1279  R.addDecl(ND);
1280  }
1281  }
1282 
1283  if (Found && S->isTemplateParamScope()) {
1284  R.resolveKind();
1285  return true;
1286  }
1287 
1288  DeclContext *Ctx = S->getEntity();
1289  if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
1290  S->getParent() && !S->getParent()->isTemplateParamScope()) {
1291  // We've just searched the last template parameter scope and
1292  // found nothing, so look into the contexts between the
1293  // lexical and semantic declaration contexts returned by
1294  // findOuterContext(). This implements the name lookup behavior
1295  // of C++ [temp.local]p8.
1296  Ctx = OutsideOfTemplateParamDC;
1297  OutsideOfTemplateParamDC = nullptr;
1298  }
1299 
1300  if (Ctx) {
1301  DeclContext *OuterCtx;
1302  bool SearchAfterTemplateScope;
1303  std::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
1304  if (SearchAfterTemplateScope)
1305  OutsideOfTemplateParamDC = OuterCtx;
1306 
1307  for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
1308  // We do not directly look into transparent contexts, since
1309  // those entities will be found in the nearest enclosing
1310  // non-transparent context.
1311  if (Ctx->isTransparentContext())
1312  continue;
1313 
1314  // If we have a context, and it's not a context stashed in the
1315  // template parameter scope for an out-of-line definition, also
1316  // look into that context.
1317  if (!(Found && S->isTemplateParamScope())) {
1318  assert(Ctx->isFileContext() &&
1319  "We should have been looking only at file context here already.");
1320 
1321  // Look into context considering using-directives.
1322  if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs))
1323  Found = true;
1324  }
1325 
1326  if (Found) {
1327  R.resolveKind();
1328  return true;
1329  }
1330 
1331  if (R.isForRedeclaration() && !Ctx->isTransparentContext())
1332  return false;
1333  }
1334  }
1335 
1336  if (R.isForRedeclaration() && Ctx && !Ctx->isTransparentContext())
1337  return false;
1338  }
1339 
1340  return !R.empty();
1341 }
1342 
1344  if (auto *M = getCurrentModule())
1345  Context.mergeDefinitionIntoModule(ND, M);
1346  else
1347  // We're not building a module; just make the definition visible.
1349 
1350  // If ND is a template declaration, make the template parameters
1351  // visible too. They're not (necessarily) within a mergeable DeclContext.
1352  if (auto *TD = dyn_cast<TemplateDecl>(ND))
1353  for (auto *Param : *TD->getTemplateParameters())
1354  makeMergedDefinitionVisible(Param);
1355 }
1356 
1357 /// Find the module in which the given declaration was defined.
1358 static Module *getDefiningModule(Sema &S, Decl *Entity) {
1359  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Entity)) {
1360  // If this function was instantiated from a template, the defining module is
1361  // the module containing the pattern.
1362  if (FunctionDecl *Pattern = FD->getTemplateInstantiationPattern())
1363  Entity = Pattern;
1364  } else if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Entity)) {
1365  if (CXXRecordDecl *Pattern = RD->getTemplateInstantiationPattern())
1366  Entity = Pattern;
1367  } else if (EnumDecl *ED = dyn_cast<EnumDecl>(Entity)) {
1368  if (auto *Pattern = ED->getTemplateInstantiationPattern())
1369  Entity = Pattern;
1370  } else if (VarDecl *VD = dyn_cast<VarDecl>(Entity)) {
1371  if (VarDecl *Pattern = VD->getTemplateInstantiationPattern())
1372  Entity = Pattern;
1373  }
1374 
1375  // Walk up to the containing context. That might also have been instantiated
1376  // from a template.
1377  DeclContext *Context = Entity->getLexicalDeclContext();
1378  if (Context->isFileContext())
1379  return S.getOwningModule(Entity);
1380  return getDefiningModule(S, cast<Decl>(Context));
1381 }
1382 
1384  unsigned N = CodeSynthesisContexts.size();
1385  for (unsigned I = CodeSynthesisContextLookupModules.size();
1386  I != N; ++I) {
1387  Module *M = getDefiningModule(*this, CodeSynthesisContexts[I].Entity);
1388  if (M && !LookupModulesCache.insert(M).second)
1389  M = nullptr;
1390  CodeSynthesisContextLookupModules.push_back(M);
1391  }
1392  return LookupModulesCache;
1393 }
1394 
1396  for (Module *Merged : Context.getModulesWithMergedDefinition(Def))
1397  if (isModuleVisible(Merged))
1398  return true;
1399  return false;
1400 }
1401 
1403  // FIXME: When not in local visibility mode, we can't tell the difference
1404  // between a declaration being visible because we merged a local copy of
1405  // the same declaration into it, and it being visible because its owning
1406  // module is visible.
1408  getLangOpts().ModulesLocalVisibility)
1409  return true;
1410  for (Module *Merged : Context.getModulesWithMergedDefinition(Def))
1411  if (Merged->getTopLevelModuleName() == getLangOpts().CurrentModule)
1412  return true;
1413  return false;
1414 }
1415 
1416 template<typename ParmDecl>
1417 static bool
1418 hasVisibleDefaultArgument(Sema &S, const ParmDecl *D,
1420  if (!D->hasDefaultArgument())
1421  return false;
1422 
1423  while (D) {
1424  auto &DefaultArg = D->getDefaultArgStorage();
1425  if (!DefaultArg.isInherited() && S.isVisible(D))
1426  return true;
1427 
1428  if (!DefaultArg.isInherited() && Modules) {
1429  auto *NonConstD = const_cast<ParmDecl*>(D);
1430  Modules->push_back(S.getOwningModule(NonConstD));
1431  const auto &Merged = S.Context.getModulesWithMergedDefinition(NonConstD);
1432  Modules->insert(Modules->end(), Merged.begin(), Merged.end());
1433  }
1434 
1435  // If there was a previous default argument, maybe its parameter is visible.
1436  D = DefaultArg.getInheritedFrom();
1437  }
1438  return false;
1439 }
1440 
1443  if (auto *P = dyn_cast<TemplateTypeParmDecl>(D))
1444  return ::hasVisibleDefaultArgument(*this, P, Modules);
1445  if (auto *P = dyn_cast<NonTypeTemplateParmDecl>(D))
1446  return ::hasVisibleDefaultArgument(*this, P, Modules);
1447  return ::hasVisibleDefaultArgument(*this, cast<TemplateTemplateParmDecl>(D),
1448  Modules);
1449 }
1450 
1451 template<typename Filter>
1452 static bool hasVisibleDeclarationImpl(Sema &S, const NamedDecl *D,
1454  Filter F) {
1455  bool HasFilteredRedecls = false;
1456 
1457  for (auto *Redecl : D->redecls()) {
1458  auto *R = cast<NamedDecl>(Redecl);
1459  if (!F(R))
1460  continue;
1461 
1462  if (S.isVisible(R))
1463  return true;
1464 
1465  HasFilteredRedecls = true;
1466 
1467  if (Modules) {
1468  Modules->push_back(R->getOwningModule());
1469  const auto &Merged = S.Context.getModulesWithMergedDefinition(R);
1470  Modules->insert(Modules->end(), Merged.begin(), Merged.end());
1471  }
1472  }
1473 
1474  // Only return false if there is at least one redecl that is not filtered out.
1475  if (HasFilteredRedecls)
1476  return false;
1477 
1478  return true;
1479 }
1480 
1482  const NamedDecl *D, llvm::SmallVectorImpl<Module *> *Modules) {
1483  return hasVisibleDeclarationImpl(*this, D, Modules, [](const NamedDecl *D) {
1484  if (auto *RD = dyn_cast<CXXRecordDecl>(D))
1485  return RD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization;
1486  if (auto *FD = dyn_cast<FunctionDecl>(D))
1487  return FD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization;
1488  if (auto *VD = dyn_cast<VarDecl>(D))
1489  return VD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization;
1490  llvm_unreachable("unknown explicit specialization kind");
1491  });
1492 }
1493 
1495  const NamedDecl *D, llvm::SmallVectorImpl<Module *> *Modules) {
1496  assert(isa<CXXRecordDecl>(D->getDeclContext()) &&
1497  "not a member specialization");
1498  return hasVisibleDeclarationImpl(*this, D, Modules, [](const NamedDecl *D) {
1499  // If the specialization is declared at namespace scope, then it's a member
1500  // specialization declaration. If it's lexically inside the class
1501  // definition then it was instantiated.
1502  //
1503  // FIXME: This is a hack. There should be a better way to determine this.
1504  // FIXME: What about MS-style explicit specializations declared within a
1505  // class definition?
1506  return D->getLexicalDeclContext()->isFileContext();
1507  });
1508 }
1509 
1510 /// Determine whether a declaration is visible to name lookup.
1511 ///
1512 /// This routine determines whether the declaration D is visible in the current
1513 /// lookup context, taking into account the current template instantiation
1514 /// stack. During template instantiation, a declaration is visible if it is
1515 /// visible from a module containing any entity on the template instantiation
1516 /// path (by instantiating a template, you allow it to see the declarations that
1517 /// your module can see, including those later on in your module).
1518 bool LookupResult::isVisibleSlow(Sema &SemaRef, NamedDecl *D) {
1519  assert(D->isHidden() && "should not call this: not in slow case");
1520 
1521  Module *DeclModule = SemaRef.getOwningModule(D);
1522  if (!DeclModule) {
1523  // A module-private declaration with no owning module means this is in the
1524  // global module in the C++ Modules TS. This is visible within the same
1525  // translation unit only.
1526  // FIXME: Don't assume that "same translation unit" means the same thing
1527  // as "not from an AST file".
1528  assert(D->isModulePrivate() && "hidden decl has no module");
1529  if (!D->isFromASTFile() || SemaRef.hasMergedDefinitionInCurrentModule(D))
1530  return true;
1531  } else {
1532  // If the owning module is visible, and the decl is not module private,
1533  // then the decl is visible too. (Module private is ignored within the same
1534  // top-level module.)
1535  if (D->isModulePrivate()
1536  ? DeclModule->getTopLevelModuleName() ==
1537  SemaRef.getLangOpts().CurrentModule ||
1539  : SemaRef.isModuleVisible(DeclModule) ||
1540  SemaRef.hasVisibleMergedDefinition(D))
1541  return true;
1542  }
1543 
1544  // Determine whether a decl context is a file context for the purpose of
1545  // visibility. This looks through some (export and linkage spec) transparent
1546  // contexts, but not others (enums).
1547  auto IsEffectivelyFileContext = [](const DeclContext *DC) {
1548  return DC->isFileContext() || isa<LinkageSpecDecl>(DC) ||
1549  isa<ExportDecl>(DC);
1550  };
1551 
1552  // If this declaration is not at namespace scope
1553  // then it is visible if its lexical parent has a visible definition.
1555  if (DC && !IsEffectivelyFileContext(DC)) {
1556  // For a parameter, check whether our current template declaration's
1557  // lexical context is visible, not whether there's some other visible
1558  // definition of it, because parameters aren't "within" the definition.
1559  //
1560  // In C++ we need to check for a visible definition due to ODR merging,
1561  // and in C we must not because each declaration of a function gets its own
1562  // set of declarations for tags in prototype scope.
1563  bool VisibleWithinParent;
1564  if (D->isTemplateParameter() || isa<ParmVarDecl>(D) ||
1565  (isa<FunctionDecl>(DC) && !SemaRef.getLangOpts().CPlusPlus))
1566  VisibleWithinParent = isVisible(SemaRef, cast<NamedDecl>(DC));
1567  else if (D->isModulePrivate()) {
1568  // A module-private declaration is only visible if an enclosing lexical
1569  // parent was merged with another definition in the current module.
1570  VisibleWithinParent = false;
1571  do {
1572  if (SemaRef.hasMergedDefinitionInCurrentModule(cast<NamedDecl>(DC))) {
1573  VisibleWithinParent = true;
1574  break;
1575  }
1576  DC = DC->getLexicalParent();
1577  } while (!IsEffectivelyFileContext(DC));
1578  } else {
1579  VisibleWithinParent = SemaRef.hasVisibleDefinition(cast<NamedDecl>(DC));
1580  }
1581 
1582  if (VisibleWithinParent && SemaRef.CodeSynthesisContexts.empty() &&
1583  // FIXME: Do something better in this case.
1584  !SemaRef.getLangOpts().ModulesLocalVisibility) {
1585  // Cache the fact that this declaration is implicitly visible because
1586  // its parent has a visible definition.
1588  }
1589  return VisibleWithinParent;
1590  }
1591 
1592  // FIXME: All uses of DeclModule below this point should also check merged
1593  // modules.
1594  if (!DeclModule)
1595  return false;
1596 
1597  // Find the extra places where we need to look.
1598  const auto &LookupModules = SemaRef.getLookupModules();
1599  if (LookupModules.empty())
1600  return false;
1601 
1602  // If our lookup set contains the decl's module, it's visible.
1603  if (LookupModules.count(DeclModule))
1604  return true;
1605 
1606  // If the declaration isn't exported, it's not visible in any other module.
1607  if (D->isModulePrivate())
1608  return false;
1609 
1610  // Check whether DeclModule is transitively exported to an import of
1611  // the lookup set.
1612  return std::any_of(LookupModules.begin(), LookupModules.end(),
1613  [&](const Module *M) {
1614  return M->isModuleVisible(DeclModule); });
1615 }
1616 
1617 bool Sema::isVisibleSlow(const NamedDecl *D) {
1618  return LookupResult::isVisible(*this, const_cast<NamedDecl*>(D));
1619 }
1620 
1621 bool Sema::shouldLinkPossiblyHiddenDecl(LookupResult &R, const NamedDecl *New) {
1622  // FIXME: If there are both visible and hidden declarations, we need to take
1623  // into account whether redeclaration is possible. Example:
1624  //
1625  // Non-imported module:
1626  // int f(T); // #1
1627  // Some TU:
1628  // static int f(U); // #2, not a redeclaration of #1
1629  // int f(T); // #3, finds both, should link with #1 if T != U, but
1630  // // with #2 if T == U; neither should be ambiguous.
1631  for (auto *D : R) {
1632  if (isVisible(D))
1633  return true;
1634  assert(D->isExternallyDeclarable() &&
1635  "should not have hidden, non-externally-declarable result here");
1636  }
1637 
1638  // This function is called once "New" is essentially complete, but before a
1639  // previous declaration is attached. We can't query the linkage of "New" in
1640  // general, because attaching the previous declaration can change the
1641  // linkage of New to match the previous declaration.
1642  //
1643  // However, because we've just determined that there is no *visible* prior
1644  // declaration, we can compute the linkage here. There are two possibilities:
1645  //
1646  // * This is not a redeclaration; it's safe to compute the linkage now.
1647  //
1648  // * This is a redeclaration of a prior declaration that is externally
1649  // redeclarable. In that case, the linkage of the declaration is not
1650  // changed by attaching the prior declaration, because both are externally
1651  // declarable (and thus ExternalLinkage or VisibleNoLinkage).
1652  //
1653  // FIXME: This is subtle and fragile.
1654  return New->isExternallyDeclarable();
1655 }
1656 
1657 /// Retrieve the visible declaration corresponding to D, if any.
1658 ///
1659 /// This routine determines whether the declaration D is visible in the current
1660 /// module, with the current imports. If not, it checks whether any
1661 /// redeclaration of D is visible, and if so, returns that declaration.
1662 ///
1663 /// \returns D, or a visible previous declaration of D, whichever is more recent
1664 /// and visible. If no declaration of D is visible, returns null.
1666  unsigned IDNS) {
1667  assert(!LookupResult::isVisible(SemaRef, D) && "not in slow case");
1668 
1669  for (auto RD : D->redecls()) {
1670  // Don't bother with extra checks if we already know this one isn't visible.
1671  if (RD == D)
1672  continue;
1673 
1674  auto ND = cast<NamedDecl>(RD);
1675  // FIXME: This is wrong in the case where the previous declaration is not
1676  // visible in the same scope as D. This needs to be done much more
1677  // carefully.
1678  if (ND->isInIdentifierNamespace(IDNS) &&
1679  LookupResult::isVisible(SemaRef, ND))
1680  return ND;
1681  }
1682 
1683  return nullptr;
1684 }
1685 
1688  assert(!isVisible(D) && "not in slow case");
1689  return hasVisibleDeclarationImpl(*this, D, Modules,
1690  [](const NamedDecl *) { return true; });
1691 }
1692 
1693 NamedDecl *LookupResult::getAcceptableDeclSlow(NamedDecl *D) const {
1694  if (auto *ND = dyn_cast<NamespaceDecl>(D)) {
1695  // Namespaces are a bit of a special case: we expect there to be a lot of
1696  // redeclarations of some namespaces, all declarations of a namespace are
1697  // essentially interchangeable, all declarations are found by name lookup
1698  // if any is, and namespaces are never looked up during template
1699  // instantiation. So we benefit from caching the check in this case, and
1700  // it is correct to do so.
1701  auto *Key = ND->getCanonicalDecl();
1702  if (auto *Acceptable = getSema().VisibleNamespaceCache.lookup(Key))
1703  return Acceptable;
1704  auto *Acceptable = isVisible(getSema(), Key)
1705  ? Key
1706  : findAcceptableDecl(getSema(), Key, IDNS);
1707  if (Acceptable)
1708  getSema().VisibleNamespaceCache.insert(std::make_pair(Key, Acceptable));
1709  return Acceptable;
1710  }
1711 
1712  return findAcceptableDecl(getSema(), D, IDNS);
1713 }
1714 
1715 /// Perform unqualified name lookup starting from a given
1716 /// scope.
1717 ///
1718 /// Unqualified name lookup (C++ [basic.lookup.unqual], C99 6.2.1) is
1719 /// used to find names within the current scope. For example, 'x' in
1720 /// @code
1721 /// int x;
1722 /// int f() {
1723 /// return x; // unqualified name look finds 'x' in the global scope
1724 /// }
1725 /// @endcode
1726 ///
1727 /// Different lookup criteria can find different names. For example, a
1728 /// particular scope can have both a struct and a function of the same
1729 /// name, and each can be found by certain lookup criteria. For more
1730 /// information about lookup criteria, see the documentation for the
1731 /// class LookupCriteria.
1732 ///
1733 /// @param S The scope from which unqualified name lookup will
1734 /// begin. If the lookup criteria permits, name lookup may also search
1735 /// in the parent scopes.
1736 ///
1737 /// @param [in,out] R Specifies the lookup to perform (e.g., the name to
1738 /// look up and the lookup kind), and is updated with the results of lookup
1739 /// including zero or more declarations and possibly additional information
1740 /// used to diagnose ambiguities.
1741 ///
1742 /// @returns \c true if lookup succeeded and false otherwise.
1743 bool Sema::LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation) {
1744  DeclarationName Name = R.getLookupName();
1745  if (!Name) return false;
1746 
1747  LookupNameKind NameKind = R.getLookupKind();
1748 
1749  if (!getLangOpts().CPlusPlus) {
1750  // Unqualified name lookup in C/Objective-C is purely lexical, so
1751  // search in the declarations attached to the name.
1752  if (NameKind == Sema::LookupRedeclarationWithLinkage) {
1753  // Find the nearest non-transparent declaration scope.
1754  while (!(S->getFlags() & Scope::DeclScope) ||
1755  (S->getEntity() && S->getEntity()->isTransparentContext()))
1756  S = S->getParent();
1757  }
1758 
1759  // When performing a scope lookup, we want to find local extern decls.
1760  FindLocalExternScope FindLocals(R);
1761 
1762  // Scan up the scope chain looking for a decl that matches this
1763  // identifier that is in the appropriate namespace. This search
1764  // should not take long, as shadowing of names is uncommon, and
1765  // deep shadowing is extremely uncommon.
1766  bool LeftStartingScope = false;
1767 
1768  for (IdentifierResolver::iterator I = IdResolver.begin(Name),
1769  IEnd = IdResolver.end();
1770  I != IEnd; ++I)
1771  if (NamedDecl *D = R.getAcceptableDecl(*I)) {
1772  if (NameKind == LookupRedeclarationWithLinkage) {
1773  // Determine whether this (or a previous) declaration is
1774  // out-of-scope.
1775  if (!LeftStartingScope && !S->isDeclScope(*I))
1776  LeftStartingScope = true;
1777 
1778  // If we found something outside of our starting scope that
1779  // does not have linkage, skip it.
1780  if (LeftStartingScope && !((*I)->hasLinkage())) {
1781  R.setShadowed();
1782  continue;
1783  }
1784  }
1785  else if (NameKind == LookupObjCImplicitSelfParam &&
1786  !isa<ImplicitParamDecl>(*I))
1787  continue;
1788 
1789  R.addDecl(D);
1790 
1791  // Check whether there are any other declarations with the same name
1792  // and in the same scope.
1793  if (I != IEnd) {
1794  // Find the scope in which this declaration was declared (if it
1795  // actually exists in a Scope).
1796  while (S && !S->isDeclScope(D))
1797  S = S->getParent();
1798 
1799  // If the scope containing the declaration is the translation unit,
1800  // then we'll need to perform our checks based on the matching
1801  // DeclContexts rather than matching scopes.
1803  S = nullptr;
1804 
1805  // Compute the DeclContext, if we need it.
1806  DeclContext *DC = nullptr;
1807  if (!S)
1808  DC = (*I)->getDeclContext()->getRedeclContext();
1809 
1810  IdentifierResolver::iterator LastI = I;
1811  for (++LastI; LastI != IEnd; ++LastI) {
1812  if (S) {
1813  // Match based on scope.
1814  if (!S->isDeclScope(*LastI))
1815  break;
1816  } else {
1817  // Match based on DeclContext.
1818  DeclContext *LastDC
1819  = (*LastI)->getDeclContext()->getRedeclContext();
1820  if (!LastDC->Equals(DC))
1821  break;
1822  }
1823 
1824  // If the declaration is in the right namespace and visible, add it.
1825  if (NamedDecl *LastD = R.getAcceptableDecl(*LastI))
1826  R.addDecl(LastD);
1827  }
1828 
1829  R.resolveKind();
1830  }
1831 
1832  return true;
1833  }
1834  } else {
1835  // Perform C++ unqualified name lookup.
1836  if (CppLookupName(R, S))
1837  return true;
1838  }
1839 
1840  // If we didn't find a use of this identifier, and if the identifier
1841  // corresponds to a compiler builtin, create the decl object for the builtin
1842  // now, injecting it into translation unit scope, and return it.
1843  if (AllowBuiltinCreation && LookupBuiltin(*this, R))
1844  return true;
1845 
1846  // If we didn't find a use of this identifier, the ExternalSource
1847  // may be able to handle the situation.
1848  // Note: some lookup failures are expected!
1849  // See e.g. R.isForRedeclaration().
1850  return (ExternalSource && ExternalSource->LookupUnqualified(R, S));
1851 }
1852 
1853 /// Perform qualified name lookup in the namespaces nominated by
1854 /// using directives by the given context.
1855 ///
1856 /// C++98 [namespace.qual]p2:
1857 /// Given X::m (where X is a user-declared namespace), or given \::m
1858 /// (where X is the global namespace), let S be the set of all
1859 /// declarations of m in X and in the transitive closure of all
1860 /// namespaces nominated by using-directives in X and its used
1861 /// namespaces, except that using-directives are ignored in any
1862 /// namespace, including X, directly containing one or more
1863 /// declarations of m. No namespace is searched more than once in
1864 /// the lookup of a name. If S is the empty set, the program is
1865 /// ill-formed. Otherwise, if S has exactly one member, or if the
1866 /// context of the reference is a using-declaration
1867 /// (namespace.udecl), S is the required set of declarations of
1868 /// m. Otherwise if the use of m is not one that allows a unique
1869 /// declaration to be chosen from S, the program is ill-formed.
1870 ///
1871 /// C++98 [namespace.qual]p5:
1872 /// During the lookup of a qualified namespace member name, if the
1873 /// lookup finds more than one declaration of the member, and if one
1874 /// declaration introduces a class name or enumeration name and the
1875 /// other declarations either introduce the same object, the same
1876 /// enumerator or a set of functions, the non-type name hides the
1877 /// class or enumeration name if and only if the declarations are
1878 /// from the same namespace; otherwise (the declarations are from
1879 /// different namespaces), the program is ill-formed.
1881  DeclContext *StartDC) {
1882  assert(StartDC->isFileContext() && "start context is not a file context");
1883 
1884  // We have not yet looked into these namespaces, much less added
1885  // their "using-children" to the queue.
1887 
1888  // We have at least added all these contexts to the queue.
1889  llvm::SmallPtrSet<DeclContext*, 8> Visited;
1890  Visited.insert(StartDC);
1891 
1892  // We have already looked into the initial namespace; seed the queue
1893  // with its using-children.
1894  for (auto *I : StartDC->using_directives()) {
1895  NamespaceDecl *ND = I->getNominatedNamespace()->getOriginalNamespace();
1896  if (S.isVisible(I) && Visited.insert(ND).second)
1897  Queue.push_back(ND);
1898  }
1899 
1900  // The easiest way to implement the restriction in [namespace.qual]p5
1901  // is to check whether any of the individual results found a tag
1902  // and, if so, to declare an ambiguity if the final result is not
1903  // a tag.
1904  bool FoundTag = false;
1905  bool FoundNonTag = false;
1906 
1908 
1909  bool Found = false;
1910  while (!Queue.empty()) {
1911  NamespaceDecl *ND = Queue.pop_back_val();
1912 
1913  // We go through some convolutions here to avoid copying results
1914  // between LookupResults.
1915  bool UseLocal = !R.empty();
1916  LookupResult &DirectR = UseLocal ? LocalR : R;
1917  bool FoundDirect = LookupDirect(S, DirectR, ND);
1918 
1919  if (FoundDirect) {
1920  // First do any local hiding.
1921  DirectR.resolveKind();
1922 
1923  // If the local result is a tag, remember that.
1924  if (DirectR.isSingleTagDecl())
1925  FoundTag = true;
1926  else
1927  FoundNonTag = true;
1928 
1929  // Append the local results to the total results if necessary.
1930  if (UseLocal) {
1931  R.addAllDecls(LocalR);
1932  LocalR.clear();
1933  }
1934  }
1935 
1936  // If we find names in this namespace, ignore its using directives.
1937  if (FoundDirect) {
1938  Found = true;
1939  continue;
1940  }
1941 
1942  for (auto I : ND->using_directives()) {
1943  NamespaceDecl *Nom = I->getNominatedNamespace();
1944  if (S.isVisible(I) && Visited.insert(Nom).second)
1945  Queue.push_back(Nom);
1946  }
1947  }
1948 
1949  if (Found) {
1950  if (FoundTag && FoundNonTag)
1952  else
1953  R.resolveKind();
1954  }
1955 
1956  return Found;
1957 }
1958 
1959 /// Callback that looks for any member of a class with the given name.
1961  CXXBasePath &Path, DeclarationName Name) {
1962  RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl();
1963 
1964  Path.Decls = BaseRecord->lookup(Name);
1965  return !Path.Decls.empty();
1966 }
1967 
1968 /// Determine whether the given set of member declarations contains only
1969 /// static members, nested types, and enumerators.
1970 template<typename InputIterator>
1971 static bool HasOnlyStaticMembers(InputIterator First, InputIterator Last) {
1972  Decl *D = (*First)->getUnderlyingDecl();
1973  if (isa<VarDecl>(D) || isa<TypeDecl>(D) || isa<EnumConstantDecl>(D))
1974  return true;
1975 
1976  if (isa<CXXMethodDecl>(D)) {
1977  // Determine whether all of the methods are static.
1978  bool AllMethodsAreStatic = true;
1979  for(; First != Last; ++First) {
1980  D = (*First)->getUnderlyingDecl();
1981 
1982  if (!isa<CXXMethodDecl>(D)) {
1983  assert(isa<TagDecl>(D) && "Non-function must be a tag decl");
1984  break;
1985  }
1986 
1987  if (!cast<CXXMethodDecl>(D)->isStatic()) {
1988  AllMethodsAreStatic = false;
1989  break;
1990  }
1991  }
1992 
1993  if (AllMethodsAreStatic)
1994  return true;
1995  }
1996 
1997  return false;
1998 }
1999 
2000 /// Perform qualified name lookup into a given context.
2001 ///
2002 /// Qualified name lookup (C++ [basic.lookup.qual]) is used to find
2003 /// names when the context of those names is explicit specified, e.g.,
2004 /// "std::vector" or "x->member", or as part of unqualified name lookup.
2005 ///
2006 /// Different lookup criteria can find different names. For example, a
2007 /// particular scope can have both a struct and a function of the same
2008 /// name, and each can be found by certain lookup criteria. For more
2009 /// information about lookup criteria, see the documentation for the
2010 /// class LookupCriteria.
2011 ///
2012 /// \param R captures both the lookup criteria and any lookup results found.
2013 ///
2014 /// \param LookupCtx The context in which qualified name lookup will
2015 /// search. If the lookup criteria permits, name lookup may also search
2016 /// in the parent contexts or (for C++ classes) base classes.
2017 ///
2018 /// \param InUnqualifiedLookup true if this is qualified name lookup that
2019 /// occurs as part of unqualified name lookup.
2020 ///
2021 /// \returns true if lookup succeeded, false if it failed.
2023  bool InUnqualifiedLookup) {
2024  assert(LookupCtx && "Sema::LookupQualifiedName requires a lookup context");
2025 
2026  if (!R.getLookupName())
2027  return false;
2028 
2029  // Make sure that the declaration context is complete.
2030  assert((!isa<TagDecl>(LookupCtx) ||
2031  LookupCtx->isDependentContext() ||
2032  cast<TagDecl>(LookupCtx)->isCompleteDefinition() ||
2033  cast<TagDecl>(LookupCtx)->isBeingDefined()) &&
2034  "Declaration context must already be complete!");
2035 
2036  struct QualifiedLookupInScope {
2037  bool oldVal;
2038  DeclContext *Context;
2039  // Set flag in DeclContext informing debugger that we're looking for qualified name
2040  QualifiedLookupInScope(DeclContext *ctx) : Context(ctx) {
2041  oldVal = ctx->setUseQualifiedLookup();
2042  }
2043  ~QualifiedLookupInScope() {
2044  Context->setUseQualifiedLookup(oldVal);
2045  }
2046  } QL(LookupCtx);
2047 
2048  if (LookupDirect(*this, R, LookupCtx)) {
2049  R.resolveKind();
2050  if (isa<CXXRecordDecl>(LookupCtx))
2051  R.setNamingClass(cast<CXXRecordDecl>(LookupCtx));
2052  return true;
2053  }
2054 
2055  // Don't descend into implied contexts for redeclarations.
2056  // C++98 [namespace.qual]p6:
2057  // In a declaration for a namespace member in which the
2058  // declarator-id is a qualified-id, given that the qualified-id
2059  // for the namespace member has the form
2060  // nested-name-specifier unqualified-id
2061  // the unqualified-id shall name a member of the namespace
2062  // designated by the nested-name-specifier.
2063  // See also [class.mfct]p5 and [class.static.data]p2.
2064  if (R.isForRedeclaration())
2065  return false;
2066 
2067  // If this is a namespace, look it up in the implied namespaces.
2068  if (LookupCtx->isFileContext())
2069  return LookupQualifiedNameInUsingDirectives(*this, R, LookupCtx);
2070 
2071  // If this isn't a C++ class, we aren't allowed to look into base
2072  // classes, we're done.
2073  CXXRecordDecl *LookupRec = dyn_cast<CXXRecordDecl>(LookupCtx);
2074  if (!LookupRec || !LookupRec->getDefinition())
2075  return false;
2076 
2077  // If we're performing qualified name lookup into a dependent class,
2078  // then we are actually looking into a current instantiation. If we have any
2079  // dependent base classes, then we either have to delay lookup until
2080  // template instantiation time (at which point all bases will be available)
2081  // or we have to fail.
2082  if (!InUnqualifiedLookup && LookupRec->isDependentContext() &&
2083  LookupRec->hasAnyDependentBases()) {
2085  return false;
2086  }
2087 
2088  // Perform lookup into our base classes.
2089  CXXBasePaths Paths;
2090  Paths.setOrigin(LookupRec);
2091 
2092  // Look for this member in our base classes
2093  bool (*BaseCallback)(const CXXBaseSpecifier *Specifier, CXXBasePath &Path,
2094  DeclarationName Name) = nullptr;
2095  switch (R.getLookupKind()) {
2096  case LookupObjCImplicitSelfParam:
2097  case LookupOrdinaryName:
2098  case LookupMemberName:
2099  case LookupRedeclarationWithLinkage:
2100  case LookupLocalFriendName:
2101  BaseCallback = &CXXRecordDecl::FindOrdinaryMember;
2102  break;
2103 
2104  case LookupTagName:
2105  BaseCallback = &CXXRecordDecl::FindTagMember;
2106  break;
2107 
2108  case LookupAnyName:
2109  BaseCallback = &LookupAnyMember;
2110  break;
2111 
2112  case LookupOMPReductionName:
2113  BaseCallback = &CXXRecordDecl::FindOMPReductionMember;
2114  break;
2115 
2116  case LookupUsingDeclName:
2117  // This lookup is for redeclarations only.
2118 
2119  case LookupOperatorName:
2120  case LookupNamespaceName:
2121  case LookupObjCProtocolName:
2122  case LookupLabel:
2123  // These lookups will never find a member in a C++ class (or base class).
2124  return false;
2125 
2126  case LookupNestedNameSpecifierName:
2128  break;
2129  }
2130 
2131  DeclarationName Name = R.getLookupName();
2132  if (!LookupRec->lookupInBases(
2133  [=](const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
2134  return BaseCallback(Specifier, Path, Name);
2135  },
2136  Paths))
2137  return false;
2138 
2139  R.setNamingClass(LookupRec);
2140 
2141  // C++ [class.member.lookup]p2:
2142  // [...] If the resulting set of declarations are not all from
2143  // sub-objects of the same type, or the set has a nonstatic member
2144  // and includes members from distinct sub-objects, there is an
2145  // ambiguity and the program is ill-formed. Otherwise that set is
2146  // the result of the lookup.
2147  QualType SubobjectType;
2148  int SubobjectNumber = 0;
2149  AccessSpecifier SubobjectAccess = AS_none;
2150 
2151  for (CXXBasePaths::paths_iterator Path = Paths.begin(), PathEnd = Paths.end();
2152  Path != PathEnd; ++Path) {
2153  const CXXBasePathElement &PathElement = Path->back();
2154 
2155  // Pick the best (i.e. most permissive i.e. numerically lowest) access
2156  // across all paths.
2157  SubobjectAccess = std::min(SubobjectAccess, Path->Access);
2158 
2159  // Determine whether we're looking at a distinct sub-object or not.
2160  if (SubobjectType.isNull()) {
2161  // This is the first subobject we've looked at. Record its type.
2162  SubobjectType = Context.getCanonicalType(PathElement.Base->getType());
2163  SubobjectNumber = PathElement.SubobjectNumber;
2164  continue;
2165  }
2166 
2167  if (SubobjectType
2168  != Context.getCanonicalType(PathElement.Base->getType())) {
2169  // We found members of the given name in two subobjects of
2170  // different types. If the declaration sets aren't the same, this
2171  // lookup is ambiguous.
2172  if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end())) {
2173  CXXBasePaths::paths_iterator FirstPath = Paths.begin();
2174  DeclContext::lookup_iterator FirstD = FirstPath->Decls.begin();
2175  DeclContext::lookup_iterator CurrentD = Path->Decls.begin();
2176 
2177  while (FirstD != FirstPath->Decls.end() &&
2178  CurrentD != Path->Decls.end()) {
2179  if ((*FirstD)->getUnderlyingDecl()->getCanonicalDecl() !=
2180  (*CurrentD)->getUnderlyingDecl()->getCanonicalDecl())
2181  break;
2182 
2183  ++FirstD;
2184  ++CurrentD;
2185  }
2186 
2187  if (FirstD == FirstPath->Decls.end() &&
2188  CurrentD == Path->Decls.end())
2189  continue;
2190  }
2191 
2193  return true;
2194  }
2195 
2196  if (SubobjectNumber != PathElement.SubobjectNumber) {
2197  // We have a different subobject of the same type.
2198 
2199  // C++ [class.member.lookup]p5:
2200  // A static member, a nested type or an enumerator defined in
2201  // a base class T can unambiguously be found even if an object
2202  // has more than one base class subobject of type T.
2203  if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end()))
2204  continue;
2205 
2206  // We have found a nonstatic member name in multiple, distinct
2207  // subobjects. Name lookup is ambiguous.
2208  R.setAmbiguousBaseSubobjects(Paths);
2209  return true;
2210  }
2211  }
2212 
2213  // Lookup in a base class succeeded; return these results.
2214 
2215  for (auto *D : Paths.front().Decls) {
2216  AccessSpecifier AS = CXXRecordDecl::MergeAccess(SubobjectAccess,
2217  D->getAccess());
2218  R.addDecl(D, AS);
2219  }
2220  R.resolveKind();
2221  return true;
2222 }
2223 
2224 /// Performs qualified name lookup or special type of lookup for
2225 /// "__super::" scope specifier.
2226 ///
2227 /// This routine is a convenience overload meant to be called from contexts
2228 /// that need to perform a qualified name lookup with an optional C++ scope
2229 /// specifier that might require special kind of lookup.
2230 ///
2231 /// \param R captures both the lookup criteria and any lookup results found.
2232 ///
2233 /// \param LookupCtx The context in which qualified name lookup will
2234 /// search.
2235 ///
2236 /// \param SS An optional C++ scope-specifier.
2237 ///
2238 /// \returns true if lookup succeeded, false if it failed.
2240  CXXScopeSpec &SS) {
2241  auto *NNS = SS.getScopeRep();
2242  if (NNS && NNS->getKind() == NestedNameSpecifier::Super)
2243  return LookupInSuper(R, NNS->getAsRecordDecl());
2244  else
2245 
2246  return LookupQualifiedName(R, LookupCtx);
2247 }
2248 
2249 /// Performs name lookup for a name that was parsed in the
2250 /// source code, and may contain a C++ scope specifier.
2251 ///
2252 /// This routine is a convenience routine meant to be called from
2253 /// contexts that receive a name and an optional C++ scope specifier
2254 /// (e.g., "N::M::x"). It will then perform either qualified or
2255 /// unqualified name lookup (with LookupQualifiedName or LookupName,
2256 /// respectively) on the given name and return those results. It will
2257 /// perform a special type of lookup for "__super::" scope specifier.
2258 ///
2259 /// @param S The scope from which unqualified name lookup will
2260 /// begin.
2261 ///
2262 /// @param SS An optional C++ scope-specifier, e.g., "::N::M".
2263 ///
2264 /// @param EnteringContext Indicates whether we are going to enter the
2265 /// context of the scope-specifier SS (if present).
2266 ///
2267 /// @returns True if any decls were found (but possibly ambiguous)
2269  bool AllowBuiltinCreation, bool EnteringContext) {
2270  if (SS && SS->isInvalid()) {
2271  // When the scope specifier is invalid, don't even look for
2272  // anything.
2273  return false;
2274  }
2275 
2276  if (SS && SS->isSet()) {
2277  NestedNameSpecifier *NNS = SS->getScopeRep();
2278  if (NNS->getKind() == NestedNameSpecifier::Super)
2279  return LookupInSuper(R, NNS->getAsRecordDecl());
2280 
2281  if (DeclContext *DC = computeDeclContext(*SS, EnteringContext)) {
2282  // We have resolved the scope specifier to a particular declaration
2283  // contex, and will perform name lookup in that context.
2284  if (!DC->isDependentContext() && RequireCompleteDeclContext(*SS, DC))
2285  return false;
2286 
2287  R.setContextRange(SS->getRange());
2288  return LookupQualifiedName(R, DC);
2289  }
2290 
2291  // We could not resolve the scope specified to a specific declaration
2292  // context, which means that SS refers to an unknown specialization.
2293  // Name lookup can't find anything in this case.
2295  R.setContextRange(SS->getRange());
2296  return false;
2297  }
2298 
2299  // Perform unqualified name lookup starting in the given scope.
2300  return LookupName(R, S, AllowBuiltinCreation);
2301 }
2302 
2303 /// Perform qualified name lookup into all base classes of the given
2304 /// class.
2305 ///
2306 /// \param R captures both the lookup criteria and any lookup results found.
2307 ///
2308 /// \param Class The context in which qualified name lookup will
2309 /// search. Name lookup will search in all base classes merging the results.
2310 ///
2311 /// @returns True if any decls were found (but possibly ambiguous)
2313  // The access-control rules we use here are essentially the rules for
2314  // doing a lookup in Class that just magically skipped the direct
2315  // members of Class itself. That is, the naming class is Class, and the
2316  // access includes the access of the base.
2317  for (const auto &BaseSpec : Class->bases()) {
2318  CXXRecordDecl *RD = cast<CXXRecordDecl>(
2319  BaseSpec.getType()->castAs<RecordType>()->getDecl());
2320  LookupResult Result(*this, R.getLookupNameInfo(), R.getLookupKind());
2321  Result.setBaseObjectType(Context.getRecordType(Class));
2322  LookupQualifiedName(Result, RD);
2323 
2324  // Copy the lookup results into the target, merging the base's access into
2325  // the path access.
2326  for (auto I = Result.begin(), E = Result.end(); I != E; ++I) {
2327  R.addDecl(I.getDecl(),
2328  CXXRecordDecl::MergeAccess(BaseSpec.getAccessSpecifier(),
2329  I.getAccess()));
2330  }
2331 
2332  Result.suppressDiagnostics();
2333  }
2334 
2335  R.resolveKind();
2336  R.setNamingClass(Class);
2337 
2338  return !R.empty();
2339 }
2340 
2341 /// Produce a diagnostic describing the ambiguity that resulted
2342 /// from name lookup.
2343 ///
2344 /// \param Result The result of the ambiguous lookup to be diagnosed.
2346  assert(Result.isAmbiguous() && "Lookup result must be ambiguous");
2347 
2348  DeclarationName Name = Result.getLookupName();
2349  SourceLocation NameLoc = Result.getNameLoc();
2350  SourceRange LookupRange = Result.getContextRange();
2351 
2352  switch (Result.getAmbiguityKind()) {
2354  CXXBasePaths *Paths = Result.getBasePaths();
2355  QualType SubobjectType = Paths->front().back().Base->getType();
2356  Diag(NameLoc, diag::err_ambiguous_member_multiple_subobjects)
2357  << Name << SubobjectType << getAmbiguousPathsDisplayString(*Paths)
2358  << LookupRange;
2359 
2360  DeclContext::lookup_iterator Found = Paths->front().Decls.begin();
2361  while (isa<CXXMethodDecl>(*Found) &&
2362  cast<CXXMethodDecl>(*Found)->isStatic())
2363  ++Found;
2364 
2365  Diag((*Found)->getLocation(), diag::note_ambiguous_member_found);
2366  break;
2367  }
2368 
2370  Diag(NameLoc, diag::err_ambiguous_member_multiple_subobject_types)
2371  << Name << LookupRange;
2372 
2373  CXXBasePaths *Paths = Result.getBasePaths();
2374  std::set<Decl *> DeclsPrinted;
2375  for (CXXBasePaths::paths_iterator Path = Paths->begin(),
2376  PathEnd = Paths->end();
2377  Path != PathEnd; ++Path) {
2378  Decl *D = Path->Decls.front();
2379  if (DeclsPrinted.insert(D).second)
2380  Diag(D->getLocation(), diag::note_ambiguous_member_found);
2381  }
2382  break;
2383  }
2384 
2386  Diag(NameLoc, diag::err_ambiguous_tag_hiding) << Name << LookupRange;
2387 
2388  llvm::SmallPtrSet<NamedDecl*, 8> TagDecls;
2389 
2390  for (auto *D : Result)
2391  if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
2392  TagDecls.insert(TD);
2393  Diag(TD->getLocation(), diag::note_hidden_tag);
2394  }
2395 
2396  for (auto *D : Result)
2397  if (!isa<TagDecl>(D))
2398  Diag(D->getLocation(), diag::note_hiding_object);
2399 
2400  // For recovery purposes, go ahead and implement the hiding.
2401  LookupResult::Filter F = Result.makeFilter();
2402  while (F.hasNext()) {
2403  if (TagDecls.count(F.next()))
2404  F.erase();
2405  }
2406  F.done();
2407  break;
2408  }
2409 
2411  Diag(NameLoc, diag::err_ambiguous_reference) << Name << LookupRange;
2412 
2413  for (auto *D : Result)
2414  Diag(D->getLocation(), diag::note_ambiguous_candidate) << D;
2415  break;
2416  }
2417  }
2418 }
2419 
2420 namespace {
2421  struct AssociatedLookup {
2422  AssociatedLookup(Sema &S, SourceLocation InstantiationLoc,
2423  Sema::AssociatedNamespaceSet &Namespaces,
2424  Sema::AssociatedClassSet &Classes)
2425  : S(S), Namespaces(Namespaces), Classes(Classes),
2426  InstantiationLoc(InstantiationLoc) {
2427  }
2428 
2429  Sema &S;
2430  Sema::AssociatedNamespaceSet &Namespaces;
2431  Sema::AssociatedClassSet &Classes;
2432  SourceLocation InstantiationLoc;
2433  };
2434 } // end anonymous namespace
2435 
2436 static void
2437 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType T);
2438 
2440  DeclContext *Ctx) {
2441  // Add the associated namespace for this class.
2442 
2443  // We don't use DeclContext::getEnclosingNamespaceContext() as this may
2444  // be a locally scoped record.
2445 
2446  // We skip out of inline namespaces. The innermost non-inline namespace
2447  // contains all names of all its nested inline namespaces anyway, so we can
2448  // replace the entire inline namespace tree with its root.
2449  while (Ctx->isRecord() || Ctx->isTransparentContext() ||
2450  Ctx->isInlineNamespace())
2451  Ctx = Ctx->getParent();
2452 
2453  if (Ctx->isFileContext())
2454  Namespaces.insert(Ctx->getPrimaryContext());
2455 }
2456 
2457 // Add the associated classes and namespaces for argument-dependent
2458 // lookup that involves a template argument (C++ [basic.lookup.koenig]p2).
2459 static void
2460 addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
2461  const TemplateArgument &Arg) {
2462  // C++ [basic.lookup.koenig]p2, last bullet:
2463  // -- [...] ;
2464  switch (Arg.getKind()) {
2466  break;
2467 
2469  // [...] the namespaces and classes associated with the types of the
2470  // template arguments provided for template type parameters (excluding
2471  // template template parameters)
2473  break;
2474 
2477  // [...] the namespaces in which any template template arguments are
2478  // defined; and the classes in which any member templates used as
2479  // template template arguments are defined.
2481  if (ClassTemplateDecl *ClassTemplate
2482  = dyn_cast<ClassTemplateDecl>(Template.getAsTemplateDecl())) {
2483  DeclContext *Ctx = ClassTemplate->getDeclContext();
2484  if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2485  Result.Classes.insert(EnclosingClass);
2486  // Add the associated namespace for this class.
2487  CollectEnclosingNamespace(Result.Namespaces, Ctx);
2488  }
2489  break;
2490  }
2491 
2496  // [Note: non-type template arguments do not contribute to the set of
2497  // associated namespaces. ]
2498  break;
2499 
2501  for (const auto &P : Arg.pack_elements())
2503  break;
2504  }
2505 }
2506 
2507 // Add the associated classes and namespaces for
2508 // argument-dependent lookup with an argument of class type
2509 // (C++ [basic.lookup.koenig]p2).
2510 static void
2511 addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
2512  CXXRecordDecl *Class) {
2513 
2514  // Just silently ignore anything whose name is __va_list_tag.
2515  if (Class->getDeclName() == Result.S.VAListTagName)
2516  return;
2517 
2518  // C++ [basic.lookup.koenig]p2:
2519  // [...]
2520  // -- If T is a class type (including unions), its associated
2521  // classes are: the class itself; the class of which it is a
2522  // member, if any; and its direct and indirect base
2523  // classes. Its associated namespaces are the namespaces in
2524  // which its associated classes are defined.
2525 
2526  // Add the class of which it is a member, if any.
2527  DeclContext *Ctx = Class->getDeclContext();
2528  if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2529  Result.Classes.insert(EnclosingClass);
2530  // Add the associated namespace for this class.
2531  CollectEnclosingNamespace(Result.Namespaces, Ctx);
2532 
2533  // Add the class itself. If we've already seen this class, we don't
2534  // need to visit base classes.
2535  //
2536  // FIXME: That's not correct, we may have added this class only because it
2537  // was the enclosing class of another class, and in that case we won't have
2538  // added its base classes yet.
2539  if (!Result.Classes.insert(Class))
2540  return;
2541 
2542  // -- If T is a template-id, its associated namespaces and classes are
2543  // the namespace in which the template is defined; for member
2544  // templates, the member template's class; the namespaces and classes
2545  // associated with the types of the template arguments provided for
2546  // template type parameters (excluding template template parameters); the
2547  // namespaces in which any template template arguments are defined; and
2548  // the classes in which any member templates used as template template
2549  // arguments are defined. [Note: non-type template arguments do not
2550  // contribute to the set of associated namespaces. ]
2552  = dyn_cast<ClassTemplateSpecializationDecl>(Class)) {
2553  DeclContext *Ctx = Spec->getSpecializedTemplate()->getDeclContext();
2554  if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2555  Result.Classes.insert(EnclosingClass);
2556  // Add the associated namespace for this class.
2557  CollectEnclosingNamespace(Result.Namespaces, Ctx);
2558 
2559  const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
2560  for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
2561  addAssociatedClassesAndNamespaces(Result, TemplateArgs[I]);
2562  }
2563 
2564  // Only recurse into base classes for complete types.
2565  if (!Result.S.isCompleteType(Result.InstantiationLoc,
2566  Result.S.Context.getRecordType(Class)))
2567  return;
2568 
2569  // Add direct and indirect base classes along with their associated
2570  // namespaces.
2572  Bases.push_back(Class);
2573  while (!Bases.empty()) {
2574  // Pop this class off the stack.
2575  Class = Bases.pop_back_val();
2576 
2577  // Visit the base classes.
2578  for (const auto &Base : Class->bases()) {
2579  const RecordType *BaseType = Base.getType()->getAs<RecordType>();
2580  // In dependent contexts, we do ADL twice, and the first time around,
2581  // the base type might be a dependent TemplateSpecializationType, or a
2582  // TemplateTypeParmType. If that happens, simply ignore it.
2583  // FIXME: If we want to support export, we probably need to add the
2584  // namespace of the template in a TemplateSpecializationType, or even
2585  // the classes and namespaces of known non-dependent arguments.
2586  if (!BaseType)
2587  continue;
2588  CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(BaseType->getDecl());
2589  if (Result.Classes.insert(BaseDecl)) {
2590  // Find the associated namespace for this base class.
2591  DeclContext *BaseCtx = BaseDecl->getDeclContext();
2592  CollectEnclosingNamespace(Result.Namespaces, BaseCtx);
2593 
2594  // Make sure we visit the bases of this base class.
2595  if (BaseDecl->bases_begin() != BaseDecl->bases_end())
2596  Bases.push_back(BaseDecl);
2597  }
2598  }
2599  }
2600 }
2601 
2602 // Add the associated classes and namespaces for
2603 // argument-dependent lookup with an argument of type T
2604 // (C++ [basic.lookup.koenig]p2).
2605 static void
2606 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType Ty) {
2607  // C++ [basic.lookup.koenig]p2:
2608  //
2609  // For each argument type T in the function call, there is a set
2610  // of zero or more associated namespaces and a set of zero or more
2611  // associated classes to be considered. The sets of namespaces and
2612  // classes is determined entirely by the types of the function
2613  // arguments (and the namespace of any template template
2614  // argument). Typedef names and using-declarations used to specify
2615  // the types do not contribute to this set. The sets of namespaces
2616  // and classes are determined in the following way:
2617 
2619  const Type *T = Ty->getCanonicalTypeInternal().getTypePtr();
2620 
2621  while (true) {
2622  switch (T->getTypeClass()) {
2623 
2624 #define TYPE(Class, Base)
2625 #define DEPENDENT_TYPE(Class, Base) case Type::Class:
2626 #define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2627 #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
2628 #define ABSTRACT_TYPE(Class, Base)
2629 #include "clang/AST/TypeNodes.def"
2630  // T is canonical. We can also ignore dependent types because
2631  // we don't need to do ADL at the definition point, but if we
2632  // wanted to implement template export (or if we find some other
2633  // use for associated classes and namespaces...) this would be
2634  // wrong.
2635  break;
2636 
2637  // -- If T is a pointer to U or an array of U, its associated
2638  // namespaces and classes are those associated with U.
2639  case Type::Pointer:
2640  T = cast<PointerType>(T)->getPointeeType().getTypePtr();
2641  continue;
2642  case Type::ConstantArray:
2643  case Type::IncompleteArray:
2644  case Type::VariableArray:
2645  T = cast<ArrayType>(T)->getElementType().getTypePtr();
2646  continue;
2647 
2648  // -- If T is a fundamental type, its associated sets of
2649  // namespaces and classes are both empty.
2650  case Type::Builtin:
2651  break;
2652 
2653  // -- If T is a class type (including unions), its associated
2654  // classes are: the class itself; the class of which it is a
2655  // member, if any; and its direct and indirect base
2656  // classes. Its associated namespaces are the namespaces in
2657  // which its associated classes are defined.
2658  case Type::Record: {
2659  CXXRecordDecl *Class =
2660  cast<CXXRecordDecl>(cast<RecordType>(T)->getDecl());
2661  addAssociatedClassesAndNamespaces(Result, Class);
2662  break;
2663  }
2664 
2665  // -- If T is an enumeration type, its associated namespace is
2666  // the namespace in which it is defined. If it is class
2667  // member, its associated class is the member's class; else
2668  // it has no associated class.
2669  case Type::Enum: {
2670  EnumDecl *Enum = cast<EnumType>(T)->getDecl();
2671 
2672  DeclContext *Ctx = Enum->getDeclContext();
2673  if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2674  Result.Classes.insert(EnclosingClass);
2675 
2676  // Add the associated namespace for this class.
2677  CollectEnclosingNamespace(Result.Namespaces, Ctx);
2678 
2679  break;
2680  }
2681 
2682  // -- If T is a function type, its associated namespaces and
2683  // classes are those associated with the function parameter
2684  // types and those associated with the return type.
2685  case Type::FunctionProto: {
2686  const FunctionProtoType *Proto = cast<FunctionProtoType>(T);
2687  for (const auto &Arg : Proto->param_types())
2688  Queue.push_back(Arg.getTypePtr());
2689  // fallthrough
2690  LLVM_FALLTHROUGH;
2691  }
2692  case Type::FunctionNoProto: {
2693  const FunctionType *FnType = cast<FunctionType>(T);
2694  T = FnType->getReturnType().getTypePtr();
2695  continue;
2696  }
2697 
2698  // -- If T is a pointer to a member function of a class X, its
2699  // associated namespaces and classes are those associated
2700  // with the function parameter types and return type,
2701  // together with those associated with X.
2702  //
2703  // -- If T is a pointer to a data member of class X, its
2704  // associated namespaces and classes are those associated
2705  // with the member type together with those associated with
2706  // X.
2707  case Type::MemberPointer: {
2708  const MemberPointerType *MemberPtr = cast<MemberPointerType>(T);
2709 
2710  // Queue up the class type into which this points.
2711  Queue.push_back(MemberPtr->getClass());
2712 
2713  // And directly continue with the pointee type.
2714  T = MemberPtr->getPointeeType().getTypePtr();
2715  continue;
2716  }
2717 
2718  // As an extension, treat this like a normal pointer.
2719  case Type::BlockPointer:
2720  T = cast<BlockPointerType>(T)->getPointeeType().getTypePtr();
2721  continue;
2722 
2723  // References aren't covered by the standard, but that's such an
2724  // obvious defect that we cover them anyway.
2725  case Type::LValueReference:
2726  case Type::RValueReference:
2727  T = cast<ReferenceType>(T)->getPointeeType().getTypePtr();
2728  continue;
2729 
2730  // These are fundamental types.
2731  case Type::Vector:
2732  case Type::ExtVector:
2733  case Type::Complex:
2734  break;
2735 
2736  // Non-deduced auto types only get here for error cases.
2737  case Type::Auto:
2738  case Type::DeducedTemplateSpecialization:
2739  break;
2740 
2741  // If T is an Objective-C object or interface type, or a pointer to an
2742  // object or interface type, the associated namespace is the global
2743  // namespace.
2744  case Type::ObjCObject:
2745  case Type::ObjCInterface:
2746  case Type::ObjCObjectPointer:
2747  Result.Namespaces.insert(Result.S.Context.getTranslationUnitDecl());
2748  break;
2749 
2750  // Atomic types are just wrappers; use the associations of the
2751  // contained type.
2752  case Type::Atomic:
2753  T = cast<AtomicType>(T)->getValueType().getTypePtr();
2754  continue;
2755  case Type::Pipe:
2756  T = cast<PipeType>(T)->getElementType().getTypePtr();
2757  continue;
2758  }
2759 
2760  if (Queue.empty())
2761  break;
2762  T = Queue.pop_back_val();
2763  }
2764 }
2765 
2766 /// Find the associated classes and namespaces for
2767 /// argument-dependent lookup for a call with the given set of
2768 /// arguments.
2769 ///
2770 /// This routine computes the sets of associated classes and associated
2771 /// namespaces searched by argument-dependent lookup
2772 /// (C++ [basic.lookup.argdep]) for a given set of arguments.
2774  SourceLocation InstantiationLoc, ArrayRef<Expr *> Args,
2775  AssociatedNamespaceSet &AssociatedNamespaces,
2776  AssociatedClassSet &AssociatedClasses) {
2777  AssociatedNamespaces.clear();
2778  AssociatedClasses.clear();
2779 
2780  AssociatedLookup Result(*this, InstantiationLoc,
2781  AssociatedNamespaces, AssociatedClasses);
2782 
2783  // C++ [basic.lookup.koenig]p2:
2784  // For each argument type T in the function call, there is a set
2785  // of zero or more associated namespaces and a set of zero or more
2786  // associated classes to be considered. The sets of namespaces and
2787  // classes is determined entirely by the types of the function
2788  // arguments (and the namespace of any template template
2789  // argument).
2790  for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
2791  Expr *Arg = Args[ArgIdx];
2792 
2793  if (Arg->getType() != Context.OverloadTy) {
2795  continue;
2796  }
2797 
2798  // [...] In addition, if the argument is the name or address of a
2799  // set of overloaded functions and/or function templates, its
2800  // associated classes and namespaces are the union of those
2801  // associated with each of the members of the set: the namespace
2802  // in which the function or function template is defined and the
2803  // classes and namespaces associated with its (non-dependent)
2804  // parameter types and return type.
2805  Arg = Arg->IgnoreParens();
2806  if (UnaryOperator *unaryOp = dyn_cast<UnaryOperator>(Arg))
2807  if (unaryOp->getOpcode() == UO_AddrOf)
2808  Arg = unaryOp->getSubExpr();
2809 
2810  UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Arg);
2811  if (!ULE) continue;
2812 
2813  for (const auto *D : ULE->decls()) {
2814  // Look through any using declarations to find the underlying function.
2815  const FunctionDecl *FDecl = D->getUnderlyingDecl()->getAsFunction();
2816 
2817  // Add the classes and namespaces associated with the parameter
2818  // types and return type of this function.
2819  addAssociatedClassesAndNamespaces(Result, FDecl->getType());
2820  }
2821  }
2822 }
2823 
2825  SourceLocation Loc,
2826  LookupNameKind NameKind,
2827  RedeclarationKind Redecl) {
2828  LookupResult R(*this, Name, Loc, NameKind, Redecl);
2829  LookupName(R, S);
2830  return R.getAsSingle<NamedDecl>();
2831 }
2832 
2833 /// Find the protocol with the given name, if any.
2835  SourceLocation IdLoc,
2836  RedeclarationKind Redecl) {
2837  Decl *D = LookupSingleName(TUScope, II, IdLoc,
2838  LookupObjCProtocolName, Redecl);
2839  return cast_or_null<ObjCProtocolDecl>(D);
2840 }
2841 
2843  QualType T1, QualType T2,
2844  UnresolvedSetImpl &Functions) {
2845  // C++ [over.match.oper]p3:
2846  // -- The set of non-member candidates is the result of the
2847  // unqualified lookup of operator@ in the context of the
2848  // expression according to the usual rules for name lookup in
2849  // unqualified function calls (3.4.2) except that all member
2850  // functions are ignored.
2852  LookupResult Operators(*this, OpName, SourceLocation(), LookupOperatorName);
2853  LookupName(Operators, S);
2854 
2855  assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous");
2856  Functions.append(Operators.begin(), Operators.end());
2857 }
2858 
2861  bool ConstArg,
2862  bool VolatileArg,
2863  bool RValueThis,
2864  bool ConstThis,
2865  bool VolatileThis) {
2866  assert(CanDeclareSpecialMemberFunction(RD) &&
2867  "doing special member lookup into record that isn't fully complete");
2868  RD = RD->getDefinition();
2869  if (RValueThis || ConstThis || VolatileThis)
2870  assert((SM == CXXCopyAssignment || SM == CXXMoveAssignment) &&
2871  "constructors and destructors always have unqualified lvalue this");
2872  if (ConstArg || VolatileArg)
2873  assert((SM != CXXDefaultConstructor && SM != CXXDestructor) &&
2874  "parameter-less special members can't have qualified arguments");
2875 
2876  // FIXME: Get the caller to pass in a location for the lookup.
2877  SourceLocation LookupLoc = RD->getLocation();
2878 
2879  llvm::FoldingSetNodeID ID;
2880  ID.AddPointer(RD);
2881  ID.AddInteger(SM);
2882  ID.AddInteger(ConstArg);
2883  ID.AddInteger(VolatileArg);
2884  ID.AddInteger(RValueThis);
2885  ID.AddInteger(ConstThis);
2886  ID.AddInteger(VolatileThis);
2887 
2888  void *InsertPoint;
2890  SpecialMemberCache.FindNodeOrInsertPos(ID, InsertPoint);
2891 
2892  // This was already cached
2893  if (Result)
2894  return *Result;
2895 
2896  Result = BumpAlloc.Allocate<SpecialMemberOverloadResultEntry>();
2897  Result = new (Result) SpecialMemberOverloadResultEntry(ID);
2898  SpecialMemberCache.InsertNode(Result, InsertPoint);
2899 
2900  if (SM == CXXDestructor) {
2901  if (RD->needsImplicitDestructor())
2902  DeclareImplicitDestructor(RD);
2903  CXXDestructorDecl *DD = RD->getDestructor();
2904  assert(DD && "record without a destructor");
2905  Result->setMethod(DD);
2906  Result->setKind(DD->isDeleted() ?
2907  SpecialMemberOverloadResult::NoMemberOrDeleted :
2908  SpecialMemberOverloadResult::Success);
2909  return *Result;
2910  }
2911 
2912  // Prepare for overload resolution. Here we construct a synthetic argument
2913  // if necessary and make sure that implicit functions are declared.
2914  CanQualType CanTy = Context.getCanonicalType(Context.getTagDeclType(RD));
2915  DeclarationName Name;
2916  Expr *Arg = nullptr;
2917  unsigned NumArgs;
2918 
2919  QualType ArgType = CanTy;
2920  ExprValueKind VK = VK_LValue;
2921 
2922  if (SM == CXXDefaultConstructor) {
2923  Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
2924  NumArgs = 0;
2926  DeclareImplicitDefaultConstructor(RD);
2927  } else {
2928  if (SM == CXXCopyConstructor || SM == CXXMoveConstructor) {
2929  Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
2930  if (RD->needsImplicitCopyConstructor())
2931  DeclareImplicitCopyConstructor(RD);
2932  if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveConstructor())
2933  DeclareImplicitMoveConstructor(RD);
2934  } else {
2935  Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
2936  if (RD->needsImplicitCopyAssignment())
2937  DeclareImplicitCopyAssignment(RD);
2938  if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveAssignment())
2939  DeclareImplicitMoveAssignment(RD);
2940  }
2941 
2942  if (ConstArg)
2943  ArgType.addConst();
2944  if (VolatileArg)
2945  ArgType.addVolatile();
2946 
2947  // This isn't /really/ specified by the standard, but it's implied
2948  // we should be working from an RValue in the case of move to ensure
2949  // that we prefer to bind to rvalue references, and an LValue in the
2950  // case of copy to ensure we don't bind to rvalue references.
2951  // Possibly an XValue is actually correct in the case of move, but
2952  // there is no semantic difference for class types in this restricted
2953  // case.
2954  if (SM == CXXCopyConstructor || SM == CXXCopyAssignment)
2955  VK = VK_LValue;
2956  else
2957  VK = VK_RValue;
2958  }
2959 
2960  OpaqueValueExpr FakeArg(LookupLoc, ArgType, VK);
2961 
2962  if (SM != CXXDefaultConstructor) {
2963  NumArgs = 1;
2964  Arg = &FakeArg;
2965  }
2966 
2967  // Create the object argument
2968  QualType ThisTy = CanTy;
2969  if (ConstThis)
2970  ThisTy.addConst();
2971  if (VolatileThis)
2972  ThisTy.addVolatile();
2973  Expr::Classification Classification =
2974  OpaqueValueExpr(LookupLoc, ThisTy,
2975  RValueThis ? VK_RValue : VK_LValue).Classify(Context);
2976 
2977  // Now we perform lookup on the name we computed earlier and do overload
2978  // resolution. Lookup is only performed directly into the class since there
2979  // will always be a (possibly implicit) declaration to shadow any others.
2981  DeclContext::lookup_result R = RD->lookup(Name);
2982 
2983  if (R.empty()) {
2984  // We might have no default constructor because we have a lambda's closure
2985  // type, rather than because there's some other declared constructor.
2986  // Every class has a copy/move constructor, copy/move assignment, and
2987  // destructor.
2988  assert(SM == CXXDefaultConstructor &&
2989  "lookup for a constructor or assignment operator was empty");
2990  Result->setMethod(nullptr);
2991  Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
2992  return *Result;
2993  }
2994 
2995  // Copy the candidates as our processing of them may load new declarations
2996  // from an external source and invalidate lookup_result.
2997  SmallVector<NamedDecl *, 8> Candidates(R.begin(), R.end());
2998 
2999  for (NamedDecl *CandDecl : Candidates) {
3000  if (CandDecl->isInvalidDecl())
3001  continue;
3002 
3003  DeclAccessPair Cand = DeclAccessPair::make(CandDecl, AS_public);
3004  auto CtorInfo = getConstructorInfo(Cand);
3005  if (CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(Cand->getUnderlyingDecl())) {
3006  if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
3007  AddMethodCandidate(M, Cand, RD, ThisTy, Classification,
3008  llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
3009  else if (CtorInfo)
3010  AddOverloadCandidate(CtorInfo.Constructor, CtorInfo.FoundDecl,
3011  llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
3012  else
3013  AddOverloadCandidate(M, Cand, llvm::makeArrayRef(&Arg, NumArgs), OCS,
3014  true);
3015  } else if (FunctionTemplateDecl *Tmpl =
3016  dyn_cast<FunctionTemplateDecl>(Cand->getUnderlyingDecl())) {
3017  if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
3018  AddMethodTemplateCandidate(
3019  Tmpl, Cand, RD, nullptr, ThisTy, Classification,
3020  llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
3021  else if (CtorInfo)
3022  AddTemplateOverloadCandidate(
3023  CtorInfo.ConstructorTmpl, CtorInfo.FoundDecl, nullptr,
3024  llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
3025  else
3026  AddTemplateOverloadCandidate(
3027  Tmpl, Cand, nullptr, llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
3028  } else {
3029  assert(isa<UsingDecl>(Cand.getDecl()) &&
3030  "illegal Kind of operator = Decl");
3031  }
3032  }
3033 
3035  switch (OCS.BestViableFunction(*this, LookupLoc, Best)) {
3036  case OR_Success:
3037  Result->setMethod(cast<CXXMethodDecl>(Best->Function));
3038  Result->setKind(SpecialMemberOverloadResult::Success);
3039  break;
3040 
3041  case OR_Deleted:
3042  Result->setMethod(cast<CXXMethodDecl>(Best->Function));
3043  Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
3044  break;
3045 
3046  case OR_Ambiguous:
3047  Result->setMethod(nullptr);
3048  Result->setKind(SpecialMemberOverloadResult::Ambiguous);
3049  break;
3050 
3051  case OR_No_Viable_Function:
3052  Result->setMethod(nullptr);
3053  Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
3054  break;
3055  }
3056 
3057  return *Result;
3058 }
3059 
3060 /// Look up the default constructor for the given class.
3063  LookupSpecialMember(Class, CXXDefaultConstructor, false, false, false,
3064  false, false);
3065 
3066  return cast_or_null<CXXConstructorDecl>(Result.getMethod());
3067 }
3068 
3069 /// Look up the copying constructor for the given class.
3071  unsigned Quals) {
3072  assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3073  "non-const, non-volatile qualifiers for copy ctor arg");
3075  LookupSpecialMember(Class, CXXCopyConstructor, Quals & Qualifiers::Const,
3076  Quals & Qualifiers::Volatile, false, false, false);
3077 
3078  return cast_or_null<CXXConstructorDecl>(Result.getMethod());
3079 }
3080 
3081 /// Look up the moving constructor for the given class.
3083  unsigned Quals) {
3085  LookupSpecialMember(Class, CXXMoveConstructor, Quals & Qualifiers::Const,
3086  Quals & Qualifiers::Volatile, false, false, false);
3087 
3088  return cast_or_null<CXXConstructorDecl>(Result.getMethod());
3089 }
3090 
3091 /// Look up the constructors for the given class.
3093  // If the implicit constructors have not yet been declared, do so now.
3094  if (CanDeclareSpecialMemberFunction(Class)) {
3095  if (Class->needsImplicitDefaultConstructor())
3096  DeclareImplicitDefaultConstructor(Class);
3097  if (Class->needsImplicitCopyConstructor())
3098  DeclareImplicitCopyConstructor(Class);
3099  if (getLangOpts().CPlusPlus11 && Class->needsImplicitMoveConstructor())
3100  DeclareImplicitMoveConstructor(Class);
3101  }
3102 
3103  CanQualType T = Context.getCanonicalType(Context.getTypeDeclType(Class));
3105  return Class->lookup(Name);
3106 }
3107 
3108 /// Look up the copying assignment operator for the given class.
3110  unsigned Quals, bool RValueThis,
3111  unsigned ThisQuals) {
3112  assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3113  "non-const, non-volatile qualifiers for copy assignment arg");
3114  assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3115  "non-const, non-volatile qualifiers for copy assignment this");
3117  LookupSpecialMember(Class, CXXCopyAssignment, Quals & Qualifiers::Const,
3118  Quals & Qualifiers::Volatile, RValueThis,
3119  ThisQuals & Qualifiers::Const,
3120  ThisQuals & Qualifiers::Volatile);
3121 
3122  return Result.getMethod();
3123 }
3124 
3125 /// Look up the moving assignment operator for the given class.
3127  unsigned Quals,
3128  bool RValueThis,
3129  unsigned ThisQuals) {
3130  assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3131  "non-const, non-volatile qualifiers for copy assignment this");
3133  LookupSpecialMember(Class, CXXMoveAssignment, Quals & Qualifiers::Const,
3134  Quals & Qualifiers::Volatile, RValueThis,
3135  ThisQuals & Qualifiers::Const,
3136  ThisQuals & Qualifiers::Volatile);
3137 
3138  return Result.getMethod();
3139 }
3140 
3141 /// Look for the destructor of the given class.
3142 ///
3143 /// During semantic analysis, this routine should be used in lieu of
3144 /// CXXRecordDecl::getDestructor().
3145 ///
3146 /// \returns The destructor for this class.
3148  return cast<CXXDestructorDecl>(LookupSpecialMember(Class, CXXDestructor,
3149  false, false, false,
3150  false, false).getMethod());
3151 }
3152 
3153 /// LookupLiteralOperator - Determine which literal operator should be used for
3154 /// a user-defined literal, per C++11 [lex.ext].
3155 ///
3156 /// Normal overload resolution is not used to select which literal operator to
3157 /// call for a user-defined literal. Look up the provided literal operator name,
3158 /// and filter the results to the appropriate set for the given argument types.
3161  ArrayRef<QualType> ArgTys,
3162  bool AllowRaw, bool AllowTemplate,
3163  bool AllowStringTemplate, bool DiagnoseMissing) {
3164  LookupName(R, S);
3165  assert(R.getResultKind() != LookupResult::Ambiguous &&
3166  "literal operator lookup can't be ambiguous");
3167 
3168  // Filter the lookup results appropriately.
3170 
3171  bool FoundRaw = false;
3172  bool FoundTemplate = false;
3173  bool FoundStringTemplate = false;
3174  bool FoundExactMatch = false;
3175 
3176  while (F.hasNext()) {
3177  Decl *D = F.next();
3178  if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(D))
3179  D = USD->getTargetDecl();
3180 
3181  // If the declaration we found is invalid, skip it.
3182  if (D->isInvalidDecl()) {
3183  F.erase();
3184  continue;
3185  }
3186 
3187  bool IsRaw = false;
3188  bool IsTemplate = false;
3189  bool IsStringTemplate = false;
3190  bool IsExactMatch = false;
3191 
3192  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
3193  if (FD->getNumParams() == 1 &&
3194  FD->getParamDecl(0)->getType()->getAs<PointerType>())
3195  IsRaw = true;
3196  else if (FD->getNumParams() == ArgTys.size()) {
3197  IsExactMatch = true;
3198  for (unsigned ArgIdx = 0; ArgIdx != ArgTys.size(); ++ArgIdx) {
3199  QualType ParamTy = FD->getParamDecl(ArgIdx)->getType();
3200  if (!Context.hasSameUnqualifiedType(ArgTys[ArgIdx], ParamTy)) {
3201  IsExactMatch = false;
3202  break;
3203  }
3204  }
3205  }
3206  }
3207  if (FunctionTemplateDecl *FD = dyn_cast<FunctionTemplateDecl>(D)) {
3208  TemplateParameterList *Params = FD->getTemplateParameters();
3209  if (Params->size() == 1)
3210  IsTemplate = true;
3211  else
3212  IsStringTemplate = true;
3213  }
3214 
3215  if (IsExactMatch) {
3216  FoundExactMatch = true;
3217  AllowRaw = false;
3218  AllowTemplate = false;
3219  AllowStringTemplate = false;
3220  if (FoundRaw || FoundTemplate || FoundStringTemplate) {
3221  // Go through again and remove the raw and template decls we've
3222  // already found.
3223  F.restart();
3224  FoundRaw = FoundTemplate = FoundStringTemplate = false;
3225  }
3226  } else if (AllowRaw && IsRaw) {
3227  FoundRaw = true;
3228  } else if (AllowTemplate && IsTemplate) {
3229  FoundTemplate = true;
3230  } else if (AllowStringTemplate && IsStringTemplate) {
3231  FoundStringTemplate = true;
3232  } else {
3233  F.erase();
3234  }
3235  }
3236 
3237  F.done();
3238 
3239  // C++11 [lex.ext]p3, p4: If S contains a literal operator with a matching
3240  // parameter type, that is used in preference to a raw literal operator
3241  // or literal operator template.
3242  if (FoundExactMatch)
3243  return LOLR_Cooked;
3244 
3245  // C++11 [lex.ext]p3, p4: S shall contain a raw literal operator or a literal
3246  // operator template, but not both.
3247  if (FoundRaw && FoundTemplate) {
3248  Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call) << R.getLookupName();
3249  for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
3250  NoteOverloadCandidate(*I, (*I)->getUnderlyingDecl()->getAsFunction());
3251  return LOLR_Error;
3252  }
3253 
3254  if (FoundRaw)
3255  return LOLR_Raw;
3256 
3257  if (FoundTemplate)
3258  return LOLR_Template;
3259 
3260  if (FoundStringTemplate)
3261  return LOLR_StringTemplate;
3262 
3263  // Didn't find anything we could use.
3264  if (DiagnoseMissing) {
3265  Diag(R.getNameLoc(), diag::err_ovl_no_viable_literal_operator)
3266  << R.getLookupName() << (int)ArgTys.size() << ArgTys[0]
3267  << (ArgTys.size() == 2 ? ArgTys[1] : QualType()) << AllowRaw
3268  << (AllowTemplate || AllowStringTemplate);
3269  return LOLR_Error;
3270  }
3271 
3272  return LOLR_ErrorNoDiagnostic;
3273 }
3274 
3276  NamedDecl *&Old = Decls[cast<NamedDecl>(New->getCanonicalDecl())];
3277 
3278  // If we haven't yet seen a decl for this key, or the last decl
3279  // was exactly this one, we're done.
3280  if (Old == nullptr || Old == New) {
3281  Old = New;
3282  return;
3283  }
3284 
3285  // Otherwise, decide which is a more recent redeclaration.
3286  FunctionDecl *OldFD = Old->getAsFunction();
3287  FunctionDecl *NewFD = New->getAsFunction();
3288 
3289  FunctionDecl *Cursor = NewFD;
3290  while (true) {
3291  Cursor = Cursor->getPreviousDecl();
3292 
3293  // If we got to the end without finding OldFD, OldFD is the newer
3294  // declaration; leave things as they are.
3295  if (!Cursor) return;
3296 
3297  // If we do find OldFD, then NewFD is newer.
3298  if (Cursor == OldFD) break;
3299 
3300  // Otherwise, keep looking.
3301  }
3302 
3303  Old = New;
3304 }
3305 
3307  ArrayRef<Expr *> Args, ADLResult &Result) {
3308  // Find all of the associated namespaces and classes based on the
3309  // arguments we have.
3310  AssociatedNamespaceSet AssociatedNamespaces;
3311  AssociatedClassSet AssociatedClasses;
3312  FindAssociatedClassesAndNamespaces(Loc, Args,
3313  AssociatedNamespaces,
3314  AssociatedClasses);
3315 
3316  // C++ [basic.lookup.argdep]p3:
3317  // Let X be the lookup set produced by unqualified lookup (3.4.1)
3318  // and let Y be the lookup set produced by argument dependent
3319  // lookup (defined as follows). If X contains [...] then Y is
3320  // empty. Otherwise Y is the set of declarations found in the
3321  // namespaces associated with the argument types as described
3322  // below. The set of declarations found by the lookup of the name
3323  // is the union of X and Y.
3324  //
3325  // Here, we compute Y and add its members to the overloaded
3326  // candidate set.
3327  for (auto *NS : AssociatedNamespaces) {
3328  // When considering an associated namespace, the lookup is the
3329  // same as the lookup performed when the associated namespace is
3330  // used as a qualifier (3.4.3.2) except that:
3331  //
3332  // -- Any using-directives in the associated namespace are
3333  // ignored.
3334  //
3335  // -- Any namespace-scope friend functions declared in
3336  // associated classes are visible within their respective
3337  // namespaces even if they are not visible during an ordinary
3338  // lookup (11.4).
3339  DeclContext::lookup_result R = NS->lookup(Name);
3340  for (auto *D : R) {
3341  auto *Underlying = D;
3342  if (auto *USD = dyn_cast<UsingShadowDecl>(D))
3343  Underlying = USD->getTargetDecl();
3344 
3345  if (!isa<FunctionDecl>(Underlying) &&
3346  !isa<FunctionTemplateDecl>(Underlying))
3347  continue;
3348 
3349  if (!isVisible(D)) {
3350  D = findAcceptableDecl(
3352  if (!D)
3353  continue;
3354  if (auto *USD = dyn_cast<UsingShadowDecl>(D))
3355  Underlying = USD->getTargetDecl();
3356  }
3357 
3358  // If the only declaration here is an ordinary friend, consider
3359  // it only if it was declared in an associated classes.
3360  if ((D->getIdentifierNamespace() & Decl::IDNS_Ordinary) == 0) {
3361  // If it's neither ordinarily visible nor a friend, we can't find it.
3363  continue;
3364 
3365  bool DeclaredInAssociatedClass = false;
3366  for (Decl *DI = D; DI; DI = DI->getPreviousDecl()) {
3367  DeclContext *LexDC = DI->getLexicalDeclContext();
3368  if (isa<CXXRecordDecl>(LexDC) &&
3369  AssociatedClasses.count(cast<CXXRecordDecl>(LexDC)) &&
3370  isVisible(cast<NamedDecl>(DI))) {
3371  DeclaredInAssociatedClass = true;
3372  break;
3373  }
3374  }
3375  if (!DeclaredInAssociatedClass)
3376  continue;
3377  }
3378 
3379  // FIXME: Preserve D as the FoundDecl.
3380  Result.insert(Underlying);
3381  }
3382  }
3383 }
3384 
3385 //----------------------------------------------------------------------------
3386 // Search for all visible declarations.
3387 //----------------------------------------------------------------------------
3389 
3390 bool VisibleDeclConsumer::includeHiddenDecls() const { return false; }
3391 
3392 namespace {
3393 
3394 class ShadowContextRAII;
3395 
3396 class VisibleDeclsRecord {
3397 public:
3398  /// An entry in the shadow map, which is optimized to store a
3399  /// single declaration (the common case) but can also store a list
3400  /// of declarations.
3401  typedef llvm::TinyPtrVector<NamedDecl*> ShadowMapEntry;
3402 
3403 private:
3404  /// A mapping from declaration names to the declarations that have
3405  /// this name within a particular scope.
3406  typedef llvm::DenseMap<DeclarationName, ShadowMapEntry> ShadowMap;
3407 
3408  /// A list of shadow maps, which is used to model name hiding.
3409  std::list<ShadowMap> ShadowMaps;
3410 
3411  /// The declaration contexts we have already visited.
3412  llvm::SmallPtrSet<DeclContext *, 8> VisitedContexts;
3413 
3414  friend class ShadowContextRAII;
3415 
3416 public:
3417  /// Determine whether we have already visited this context
3418  /// (and, if not, note that we are going to visit that context now).
3419  bool visitedContext(DeclContext *Ctx) {
3420  return !VisitedContexts.insert(Ctx).second;
3421  }
3422 
3423  bool alreadyVisitedContext(DeclContext *Ctx) {
3424  return VisitedContexts.count(Ctx);
3425  }
3426 
3427  /// Determine whether the given declaration is hidden in the
3428  /// current scope.
3429  ///
3430  /// \returns the declaration that hides the given declaration, or
3431  /// NULL if no such declaration exists.
3432  NamedDecl *checkHidden(NamedDecl *ND);
3433 
3434  /// Add a declaration to the current shadow map.
3435  void add(NamedDecl *ND) {
3436  ShadowMaps.back()[ND->getDeclName()].push_back(ND);
3437  }
3438 };
3439 
3440 /// RAII object that records when we've entered a shadow context.
3441 class ShadowContextRAII {
3442  VisibleDeclsRecord &Visible;
3443 
3444  typedef VisibleDeclsRecord::ShadowMap ShadowMap;
3445 
3446 public:
3447  ShadowContextRAII(VisibleDeclsRecord &Visible) : Visible(Visible) {
3448  Visible.ShadowMaps.emplace_back();
3449  }
3450 
3451  ~ShadowContextRAII() {
3452  Visible.ShadowMaps.pop_back();
3453  }
3454 };
3455 
3456 } // end anonymous namespace
3457 
3458 NamedDecl *VisibleDeclsRecord::checkHidden(NamedDecl *ND) {
3459  unsigned IDNS = ND->getIdentifierNamespace();
3460  std::list<ShadowMap>::reverse_iterator SM = ShadowMaps.rbegin();
3461  for (std::list<ShadowMap>::reverse_iterator SMEnd = ShadowMaps.rend();
3462  SM != SMEnd; ++SM) {
3463  ShadowMap::iterator Pos = SM->find(ND->getDeclName());
3464  if (Pos == SM->end())
3465  continue;
3466 
3467  for (auto *D : Pos->second) {
3468  // A tag declaration does not hide a non-tag declaration.
3469  if (D->hasTagIdentifierNamespace() &&
3472  continue;
3473 
3474  // Protocols are in distinct namespaces from everything else.
3476  || (IDNS & Decl::IDNS_ObjCProtocol)) &&
3477  D->getIdentifierNamespace() != IDNS)
3478  continue;
3479 
3480  // Functions and function templates in the same scope overload
3481  // rather than hide. FIXME: Look for hiding based on function
3482  // signatures!
3485  SM == ShadowMaps.rbegin())
3486  continue;
3487 
3488  // A shadow declaration that's created by a resolved using declaration
3489  // is not hidden by the same using declaration.
3490  if (isa<UsingShadowDecl>(ND) && isa<UsingDecl>(D) &&
3491  cast<UsingShadowDecl>(ND)->getUsingDecl() == D)
3492  continue;
3493 
3494  // We've found a declaration that hides this one.
3495  return D;
3496  }
3497  }
3498 
3499  return nullptr;
3500 }
3501 
3502 static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
3503  bool QualifiedNameLookup,
3504  bool InBaseClass,
3505  VisibleDeclConsumer &Consumer,
3506  VisibleDeclsRecord &Visited,
3507  bool IncludeDependentBases,
3508  bool LoadExternal) {
3509  if (!Ctx)
3510  return;
3511 
3512  // Make sure we don't visit the same context twice.
3513  if (Visited.visitedContext(Ctx->getPrimaryContext()))
3514  return;
3515 
3516  Consumer.EnteredContext(Ctx);
3517 
3518  // Outside C++, lookup results for the TU live on identifiers.
3519  if (isa<TranslationUnitDecl>(Ctx) &&
3520  !Result.getSema().getLangOpts().CPlusPlus) {
3521  auto &S = Result.getSema();
3522  auto &Idents = S.Context.Idents;
3523 
3524  // Ensure all external identifiers are in the identifier table.
3525  if (LoadExternal)
3526  if (IdentifierInfoLookup *External = Idents.getExternalIdentifierLookup()) {
3527  std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
3528  for (StringRef Name = Iter->Next(); !Name.empty(); Name = Iter->Next())
3529  Idents.get(Name);
3530  }
3531 
3532  // Walk all lookup results in the TU for each identifier.
3533  for (const auto &Ident : Idents) {
3534  for (auto I = S.IdResolver.begin(Ident.getValue()),
3535  E = S.IdResolver.end();
3536  I != E; ++I) {
3537  if (S.IdResolver.isDeclInScope(*I, Ctx)) {
3538  if (NamedDecl *ND = Result.getAcceptableDecl(*I)) {
3539  Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
3540  Visited.add(ND);
3541  }
3542  }
3543  }
3544  }
3545 
3546  return;
3547  }
3548 
3549  if (CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(Ctx))
3551 
3552  // We sometimes skip loading namespace-level results (they tend to be huge).
3553  bool Load = LoadExternal ||
3554  !(isa<TranslationUnitDecl>(Ctx) || isa<NamespaceDecl>(Ctx));
3555  // Enumerate all of the results in this context.
3556  for (DeclContextLookupResult R :
3557  Load ? Ctx->lookups()
3558  : Ctx->noload_lookups(/*PreserveInternalState=*/false)) {
3559  for (auto *D : R) {
3560  if (auto *ND = Result.getAcceptableDecl(D)) {
3561  Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
3562  Visited.add(ND);
3563  }
3564  }
3565  }
3566 
3567  // Traverse using directives for qualified name lookup.
3568  if (QualifiedNameLookup) {
3569  ShadowContextRAII Shadow(Visited);
3570  for (auto I : Ctx->using_directives()) {
3571  if (!Result.getSema().isVisible(I))
3572  continue;
3573  LookupVisibleDecls(I->getNominatedNamespace(), Result,
3574  QualifiedNameLookup, InBaseClass, Consumer, Visited,
3575  IncludeDependentBases, LoadExternal);
3576  }
3577  }
3578 
3579  // Traverse the contexts of inherited C++ classes.
3580  if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) {
3581  if (!Record->hasDefinition())
3582  return;
3583 
3584  for (const auto &B : Record->bases()) {
3585  QualType BaseType = B.getType();
3586 
3587  RecordDecl *RD;
3588  if (BaseType->isDependentType()) {
3589  if (!IncludeDependentBases) {
3590  // Don't look into dependent bases, because name lookup can't look
3591  // there anyway.
3592  continue;
3593  }
3594  const auto *TST = BaseType->getAs<TemplateSpecializationType>();
3595  if (!TST)
3596  continue;
3597  TemplateName TN = TST->getTemplateName();
3598  const auto *TD =
3599  dyn_cast_or_null<ClassTemplateDecl>(TN.getAsTemplateDecl());
3600  if (!TD)
3601  continue;
3602  RD = TD->getTemplatedDecl();
3603  } else {
3604  const auto *Record = BaseType->getAs<RecordType>();
3605  if (!Record)
3606  continue;
3607  RD = Record->getDecl();
3608  }
3609 
3610  // FIXME: It would be nice to be able to determine whether referencing
3611  // a particular member would be ambiguous. For example, given
3612  //
3613  // struct A { int member; };
3614  // struct B { int member; };
3615  // struct C : A, B { };
3616  //
3617  // void f(C *c) { c->### }
3618  //
3619  // accessing 'member' would result in an ambiguity. However, we
3620  // could be smart enough to qualify the member with the base
3621  // class, e.g.,
3622  //
3623  // c->B::member
3624  //
3625  // or
3626  //
3627  // c->A::member
3628 
3629  // Find results in this base class (and its bases).
3630  ShadowContextRAII Shadow(Visited);
3631  LookupVisibleDecls(RD, Result, QualifiedNameLookup, true, Consumer,
3632  Visited, IncludeDependentBases, LoadExternal);
3633  }
3634  }
3635 
3636  // Traverse the contexts of Objective-C classes.
3637  if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(Ctx)) {
3638  // Traverse categories.
3639  for (auto *Cat : IFace->visible_categories()) {
3640  ShadowContextRAII Shadow(Visited);
3641  LookupVisibleDecls(Cat, Result, QualifiedNameLookup, false, Consumer,
3642  Visited, IncludeDependentBases, LoadExternal);
3643  }
3644 
3645  // Traverse protocols.
3646  for (auto *I : IFace->all_referenced_protocols()) {
3647  ShadowContextRAII Shadow(Visited);
3648  LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3649  Visited, IncludeDependentBases, LoadExternal);
3650  }
3651 
3652  // Traverse the superclass.
3653  if (IFace->getSuperClass()) {
3654  ShadowContextRAII Shadow(Visited);
3655  LookupVisibleDecls(IFace->getSuperClass(), Result, QualifiedNameLookup,
3656  true, Consumer, Visited, IncludeDependentBases,
3657  LoadExternal);
3658  }
3659 
3660  // If there is an implementation, traverse it. We do this to find
3661  // synthesized ivars.
3662  if (IFace->getImplementation()) {
3663  ShadowContextRAII Shadow(Visited);
3664  LookupVisibleDecls(IFace->getImplementation(), Result,
3665  QualifiedNameLookup, InBaseClass, Consumer, Visited,
3666  IncludeDependentBases, LoadExternal);
3667  }
3668  } else if (ObjCProtocolDecl *Protocol = dyn_cast<ObjCProtocolDecl>(Ctx)) {
3669  for (auto *I : Protocol->protocols()) {
3670  ShadowContextRAII Shadow(Visited);
3671  LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3672  Visited, IncludeDependentBases, LoadExternal);
3673  }
3674  } else if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(Ctx)) {
3675  for (auto *I : Category->protocols()) {
3676  ShadowContextRAII Shadow(Visited);
3677  LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3678  Visited, IncludeDependentBases, LoadExternal);
3679  }
3680 
3681  // If there is an implementation, traverse it.
3682  if (Category->getImplementation()) {
3683  ShadowContextRAII Shadow(Visited);
3684  LookupVisibleDecls(Category->getImplementation(), Result,
3685  QualifiedNameLookup, true, Consumer, Visited,
3686  IncludeDependentBases, LoadExternal);
3687  }
3688  }
3689 }
3690 
3691 static void LookupVisibleDecls(Scope *S, LookupResult &Result,
3692  UnqualUsingDirectiveSet &UDirs,
3693  VisibleDeclConsumer &Consumer,
3694  VisibleDeclsRecord &Visited,
3695  bool LoadExternal) {
3696  if (!S)
3697  return;
3698 
3699  if (!S->getEntity() ||
3700  (!S->getParent() &&
3701  !Visited.alreadyVisitedContext(S->getEntity())) ||
3702  (S->getEntity())->isFunctionOrMethod()) {
3703  FindLocalExternScope FindLocals(Result);
3704  // Walk through the declarations in this Scope. The consumer might add new
3705  // decls to the scope as part of deserialization, so make a copy first.
3706  SmallVector<Decl *, 8> ScopeDecls(S->decls().begin(), S->decls().end());
3707  for (Decl *D : ScopeDecls) {
3708  if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
3709  if ((ND = Result.getAcceptableDecl(ND))) {
3710  Consumer.FoundDecl(ND, Visited.checkHidden(ND), nullptr, false);
3711  Visited.add(ND);
3712  }
3713  }
3714  }
3715 
3716  // FIXME: C++ [temp.local]p8
3717  DeclContext *Entity = nullptr;
3718  if (S->getEntity()) {
3719  // Look into this scope's declaration context, along with any of its
3720  // parent lookup contexts (e.g., enclosing classes), up to the point
3721  // where we hit the context stored in the next outer scope.
3722  Entity = S->getEntity();
3723  DeclContext *OuterCtx = findOuterContext(S).first; // FIXME
3724 
3725  for (DeclContext *Ctx = Entity; Ctx && !Ctx->Equals(OuterCtx);
3726  Ctx = Ctx->getLookupParent()) {
3727  if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
3728  if (Method->isInstanceMethod()) {
3729  // For instance methods, look for ivars in the method's interface.
3730  LookupResult IvarResult(Result.getSema(), Result.getLookupName(),
3732  if (ObjCInterfaceDecl *IFace = Method->getClassInterface()) {
3733  LookupVisibleDecls(IFace, IvarResult, /*QualifiedNameLookup=*/false,
3734  /*InBaseClass=*/false, Consumer, Visited,
3735  /*IncludeDependentBases=*/false, LoadExternal);
3736  }
3737  }
3738 
3739  // We've already performed all of the name lookup that we need
3740  // to for Objective-C methods; the next context will be the
3741  // outer scope.
3742  break;
3743  }
3744 
3745  if (Ctx->isFunctionOrMethod())
3746  continue;
3747 
3748  LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/false,
3749  /*InBaseClass=*/false, Consumer, Visited,
3750  /*IncludeDependentBases=*/false, LoadExternal);
3751  }
3752  } else if (!S->getParent()) {
3753  // Look into the translation unit scope. We walk through the translation
3754  // unit's declaration context, because the Scope itself won't have all of
3755  // the declarations if we loaded a precompiled header.
3756  // FIXME: We would like the translation unit's Scope object to point to the
3757  // translation unit, so we don't need this special "if" branch. However,
3758  // doing so would force the normal C++ name-lookup code to look into the
3759  // translation unit decl when the IdentifierInfo chains would suffice.
3760  // Once we fix that problem (which is part of a more general "don't look
3761  // in DeclContexts unless we have to" optimization), we can eliminate this.
3762  Entity = Result.getSema().Context.getTranslationUnitDecl();
3763  LookupVisibleDecls(Entity, Result, /*QualifiedNameLookup=*/false,
3764  /*InBaseClass=*/false, Consumer, Visited,
3765  /*IncludeDependentBases=*/false, LoadExternal);
3766  }
3767 
3768  if (Entity) {
3769  // Lookup visible declarations in any namespaces found by using
3770  // directives.
3771  for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(Entity))
3772  LookupVisibleDecls(const_cast<DeclContext *>(UUE.getNominatedNamespace()),
3773  Result, /*QualifiedNameLookup=*/false,
3774  /*InBaseClass=*/false, Consumer, Visited,
3775  /*IncludeDependentBases=*/false, LoadExternal);
3776  }
3777 
3778  // Lookup names in the parent scope.
3779  ShadowContextRAII Shadow(Visited);
3780  LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited,
3781  LoadExternal);
3782 }
3783 
3785  VisibleDeclConsumer &Consumer,
3786  bool IncludeGlobalScope, bool LoadExternal) {
3787  // Determine the set of using directives available during
3788  // unqualified name lookup.
3789  Scope *Initial = S;
3790  UnqualUsingDirectiveSet UDirs(*this);
3791  if (getLangOpts().CPlusPlus) {
3792  // Find the first namespace or translation-unit scope.
3793  while (S && !isNamespaceOrTranslationUnitScope(S))
3794  S = S->getParent();
3795 
3796  UDirs.visitScopeChain(Initial, S);
3797  }
3798  UDirs.done();
3799 
3800  // Look for visible declarations.
3801  LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
3802  Result.setAllowHidden(Consumer.includeHiddenDecls());
3803  VisibleDeclsRecord Visited;
3804  if (!IncludeGlobalScope)
3805  Visited.visitedContext(Context.getTranslationUnitDecl());
3806  ShadowContextRAII Shadow(Visited);
3807  ::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited, LoadExternal);
3808 }
3809 
3811  VisibleDeclConsumer &Consumer,
3812  bool IncludeGlobalScope,
3813  bool IncludeDependentBases, bool LoadExternal) {
3814  LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
3815  Result.setAllowHidden(Consumer.includeHiddenDecls());
3816  VisibleDeclsRecord Visited;
3817  if (!IncludeGlobalScope)
3818  Visited.visitedContext(Context.getTranslationUnitDecl());
3819  ShadowContextRAII Shadow(Visited);
3820  ::LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/true,
3821  /*InBaseClass=*/false, Consumer, Visited,
3822  IncludeDependentBases, LoadExternal);
3823 }
3824 
3825 /// LookupOrCreateLabel - Do a name lookup of a label with the specified name.
3826 /// If GnuLabelLoc is a valid source location, then this is a definition
3827 /// of an __label__ label name, otherwise it is a normal label definition
3828 /// or use.
3830  SourceLocation GnuLabelLoc) {
3831  // Do a lookup to see if we have a label with this name already.
3832  NamedDecl *Res = nullptr;
3833 
3834  if (GnuLabelLoc.isValid()) {
3835  // Local label definitions always shadow existing labels.
3836  Res = LabelDecl::Create(Context, CurContext, Loc, II, GnuLabelLoc);
3837  Scope *S = CurScope;
3838  PushOnScopeChains(Res, S, true);
3839  return cast<LabelDecl>(Res);
3840  }
3841 
3842  // Not a GNU local label.
3843  Res = LookupSingleName(CurScope, II, Loc, LookupLabel, NotForRedeclaration);
3844  // If we found a label, check to see if it is in the same context as us.
3845  // When in a Block, we don't want to reuse a label in an enclosing function.
3846  if (Res && Res->getDeclContext() != CurContext)
3847  Res = nullptr;
3848  if (!Res) {
3849  // If not forward referenced or defined already, create the backing decl.
3850  Res = LabelDecl::Create(Context, CurContext, Loc, II);
3851  Scope *S = CurScope->getFnParent();
3852  assert(S && "Not in a function?");
3853  PushOnScopeChains(Res, S, true);
3854  }
3855  return cast<LabelDecl>(Res);
3856 }
3857 
3858 //===----------------------------------------------------------------------===//
3859 // Typo correction
3860 //===----------------------------------------------------------------------===//
3861 
3863  TypoCorrection &Candidate) {
3864  Candidate.setCallbackDistance(CCC.RankCandidate(Candidate));
3865  return Candidate.getEditDistance(false) != TypoCorrection::InvalidDistance;
3866 }
3867 
3868 static void LookupPotentialTypoResult(Sema &SemaRef,
3869  LookupResult &Res,
3870  IdentifierInfo *Name,
3871  Scope *S, CXXScopeSpec *SS,
3873  bool EnteringContext,
3874  bool isObjCIvarLookup,
3875  bool FindHidden);
3876 
3877 /// Check whether the declarations found for a typo correction are
3878 /// visible. Set the correction's RequiresImport flag to true if none of the
3879 /// declarations are visible, false otherwise.
3880 static void checkCorrectionVisibility(Sema &SemaRef, TypoCorrection &TC) {
3881  TypoCorrection::decl_iterator DI = TC.begin(), DE = TC.end();
3882 
3883  for (/**/; DI != DE; ++DI)
3884  if (!LookupResult::isVisible(SemaRef, *DI))
3885  break;
3886  // No filtering needed if all decls are visible.
3887  if (DI == DE) {
3888  TC.setRequiresImport(false);
3889  return;
3890  }
3891 
3892  llvm::SmallVector<NamedDecl*, 4> NewDecls(TC.begin(), DI);
3893  bool AnyVisibleDecls = !NewDecls.empty();
3894 
3895  for (/**/; DI != DE; ++DI) {
3896  if (LookupResult::isVisible(SemaRef, *DI)) {
3897  if (!AnyVisibleDecls) {
3898  // Found a visible decl, discard all hidden ones.
3899  AnyVisibleDecls = true;
3900  NewDecls.clear();
3901  }
3902  NewDecls.push_back(*DI);
3903  } else if (!AnyVisibleDecls && !(*DI)->isModulePrivate())
3904  NewDecls.push_back(*DI);
3905  }
3906 
3907  if (NewDecls.empty())
3908  TC = TypoCorrection();
3909  else {
3910  TC.setCorrectionDecls(NewDecls);
3911  TC.setRequiresImport(!AnyVisibleDecls);
3912  }
3913 }
3914 
3915 // Fill the supplied vector with the IdentifierInfo pointers for each piece of
3916 // the given NestedNameSpecifier (i.e. given a NestedNameSpecifier "foo::bar::",
3917 // fill the vector with the IdentifierInfo pointers for "foo" and "bar").
3919  NestedNameSpecifier *NNS,
3921  if (NestedNameSpecifier *Prefix = NNS->getPrefix())
3922  getNestedNameSpecifierIdentifiers(Prefix, Identifiers);
3923  else
3924  Identifiers.clear();
3925 
3926  const IdentifierInfo *II = nullptr;
3927 
3928  switch (NNS->getKind()) {
3930  II = NNS->getAsIdentifier();
3931  break;
3932 
3934  if (NNS->getAsNamespace()->isAnonymousNamespace())
3935  return;
3936  II = NNS->getAsNamespace()->getIdentifier();
3937  break;
3938 
3940  II = NNS->getAsNamespaceAlias()->getIdentifier();
3941  break;
3942 
3945  II = QualType(NNS->getAsType(), 0).getBaseTypeIdentifier();
3946  break;
3947 
3950  return;
3951  }
3952 
3953  if (II)
3954  Identifiers.push_back(II);
3955 }
3956 
3958  DeclContext *Ctx, bool InBaseClass) {
3959  // Don't consider hidden names for typo correction.
3960  if (Hiding)
3961  return;
3962 
3963  // Only consider entities with identifiers for names, ignoring
3964  // special names (constructors, overloaded operators, selectors,
3965  // etc.).
3966  IdentifierInfo *Name = ND->getIdentifier();
3967  if (!Name)
3968  return;
3969 
3970  // Only consider visible declarations and declarations from modules with
3971  // names that exactly match.
3972  if (!LookupResult::isVisible(SemaRef, ND) && Name != Typo)
3973  return;
3974 
3975  FoundName(Name->getName());
3976 }
3977 
3979  // Compute the edit distance between the typo and the name of this
3980  // entity, and add the identifier to the list of results.
3981  addName(Name, nullptr);
3982 }
3983 
3985  // Compute the edit distance between the typo and this keyword,
3986  // and add the keyword to the list of results.
3987  addName(Keyword, nullptr, nullptr, true);
3988 }
3989 
3990 void TypoCorrectionConsumer::addName(StringRef Name, NamedDecl *ND,
3991  NestedNameSpecifier *NNS, bool isKeyword) {
3992  // Use a simple length-based heuristic to determine the minimum possible
3993  // edit distance. If the minimum isn't good enough, bail out early.
3994  StringRef TypoStr = Typo->getName();
3995  unsigned MinED = abs((int)Name.size() - (int)TypoStr.size());
3996  if (MinED && TypoStr.size() / MinED < 3)
3997  return;
3998 
3999  // Compute an upper bound on the allowable edit distance, so that the
4000  // edit-distance algorithm can short-circuit.
4001  unsigned UpperBound = (TypoStr.size() + 2) / 3 + 1;
4002  unsigned ED = TypoStr.edit_distance(Name, true, UpperBound);
4003  if (ED >= UpperBound) return;
4004 
4005  TypoCorrection TC(&SemaRef.Context.Idents.get(Name), ND, NNS, ED);
4006  if (isKeyword) TC.makeKeyword();
4007  TC.setCorrectionRange(nullptr, Result.getLookupNameInfo());
4008  addCorrection(TC);
4009 }
4010 
4011 static const unsigned MaxTypoDistanceResultSets = 5;
4012 
4014  StringRef TypoStr = Typo->getName();
4015  StringRef Name = Correction.getCorrectionAsIdentifierInfo()->getName();
4016 
4017  // For very short typos, ignore potential corrections that have a different
4018  // base identifier from the typo or which have a normalized edit distance
4019  // longer than the typo itself.
4020  if (TypoStr.size() < 3 &&
4021  (Name != TypoStr || Correction.getEditDistance(true) > TypoStr.size()))
4022  return;
4023 
4024  // If the correction is resolved but is not viable, ignore it.
4025  if (Correction.isResolved()) {
4026  checkCorrectionVisibility(SemaRef, Correction);
4027  if (!Correction || !isCandidateViable(*CorrectionValidator, Correction))
4028  return;
4029  }
4030 
4031  TypoResultList &CList =
4032  CorrectionResults[Correction.getEditDistance(false)][Name];
4033 
4034  if (!CList.empty() && !CList.back().isResolved())
4035  CList.pop_back();
4036  if (NamedDecl *NewND = Correction.getCorrectionDecl()) {
4037  std::string CorrectionStr = Correction.getAsString(SemaRef.getLangOpts());
4038  for (TypoResultList::iterator RI = CList.begin(), RIEnd = CList.end();
4039  RI != RIEnd; ++RI) {
4040  // If the Correction refers to a decl already in the result list,
4041  // replace the existing result if the string representation of Correction
4042  // comes before the current result alphabetically, then stop as there is
4043  // nothing more to be done to add Correction to the candidate set.
4044  if (RI->getCorrectionDecl() == NewND) {
4045  if (CorrectionStr < RI->getAsString(SemaRef.getLangOpts()))
4046  *RI = Correction;
4047  return;
4048  }
4049  }
4050  }
4051  if (CList.empty() || Correction.isResolved())
4052  CList.push_back(Correction);
4053 
4054  while (CorrectionResults.size() > MaxTypoDistanceResultSets)
4055  CorrectionResults.erase(std::prev(CorrectionResults.end()));
4056 }
4057 
4059  const llvm::MapVector<NamespaceDecl *, bool> &KnownNamespaces) {
4060  SearchNamespaces = true;
4061 
4062  for (auto KNPair : KnownNamespaces)
4063  Namespaces.addNameSpecifier(KNPair.first);
4064 
4065  bool SSIsTemplate = false;
4066  if (NestedNameSpecifier *NNS =
4067  (SS && SS->isValid()) ? SS->getScopeRep() : nullptr) {
4068  if (const Type *T = NNS->getAsType())
4069  SSIsTemplate = T->getTypeClass() == Type::TemplateSpecialization;
4070  }
4071  // Do not transform this into an iterator-based loop. The loop body can
4072  // trigger the creation of further types (through lazy deserialization) and
4073  // invalide iterators into this list.
4074  auto &Types = SemaRef.getASTContext().getTypes();
4075  for (unsigned I = 0; I != Types.size(); ++I) {
4076  const auto *TI = Types[I];
4077  if (CXXRecordDecl *CD = TI->getAsCXXRecordDecl()) {
4078  CD = CD->getCanonicalDecl();
4079  if (!CD->isDependentType() && !CD->isAnonymousStructOrUnion() &&
4080  !CD->isUnion() && CD->getIdentifier() &&
4081  (SSIsTemplate || !isa<ClassTemplateSpecializationDecl>(CD)) &&
4082  (CD->isBeingDefined() || CD->isCompleteDefinition()))
4083  Namespaces.addNameSpecifier(CD);
4084  }
4085  }
4086 }
4087 
4089  if (++CurrentTCIndex < ValidatedCorrections.size())
4090  return ValidatedCorrections[CurrentTCIndex];
4091 
4092  CurrentTCIndex = ValidatedCorrections.size();
4093  while (!CorrectionResults.empty()) {
4094  auto DI = CorrectionResults.begin();
4095  if (DI->second.empty()) {
4096  CorrectionResults.erase(DI);
4097  continue;
4098  }
4099 
4100  auto RI = DI->second.begin();
4101  if (RI->second.empty()) {
4102  DI->second.erase(RI);
4103  performQualifiedLookups();
4104  continue;
4105  }
4106 
4107  TypoCorrection TC = RI->second.pop_back_val();
4108  if (TC.isResolved() || TC.requiresImport() || resolveCorrection(TC)) {
4109  ValidatedCorrections.push_back(TC);
4110  return ValidatedCorrections[CurrentTCIndex];
4111  }
4112  }
4113  return ValidatedCorrections[0]; // The empty correction.
4114 }
4115 
4116 bool TypoCorrectionConsumer::resolveCorrection(TypoCorrection &Candidate) {
4117  IdentifierInfo *Name = Candidate.getCorrectionAsIdentifierInfo();
4118  DeclContext *TempMemberContext = MemberContext;
4119  CXXScopeSpec *TempSS = SS.get();
4120 retry_lookup:
4121  LookupPotentialTypoResult(SemaRef, Result, Name, S, TempSS, TempMemberContext,
4122  EnteringContext,
4123  CorrectionValidator->IsObjCIvarLookup,
4124  Name == Typo && !Candidate.WillReplaceSpecifier());
4125  switch (Result.getResultKind()) {
4129  if (TempSS) {
4130  // Immediately retry the lookup without the given CXXScopeSpec
4131  TempSS = nullptr;
4132  Candidate.WillReplaceSpecifier(true);
4133  goto retry_lookup;
4134  }
4135  if (TempMemberContext) {
4136  if (SS && !TempSS)
4137  TempSS = SS.get();
4138  TempMemberContext = nullptr;
4139  goto retry_lookup;
4140  }
4141  if (SearchNamespaces)
4142  QualifiedResults.push_back(Candidate);
4143  break;
4144 
4146  // We don't deal with ambiguities.
4147  break;
4148 
4149  case LookupResult::Found:
4151  // Store all of the Decls for overloaded symbols
4152  for (auto *TRD : Result)
4153  Candidate.addCorrectionDecl(TRD);
4154  checkCorrectionVisibility(SemaRef, Candidate);
4155  if (!isCandidateViable(*CorrectionValidator, Candidate)) {
4156  if (SearchNamespaces)
4157  QualifiedResults.push_back(Candidate);
4158  break;
4159  }
4160  Candidate.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
4161  return true;
4162  }
4163  return false;
4164 }
4165 
4166 void TypoCorrectionConsumer::performQualifiedLookups() {
4167  unsigned TypoLen = Typo->getName().size();
4168  for (const TypoCorrection &QR : QualifiedResults) {
4169  for (const auto &NSI : Namespaces) {
4170  DeclContext *Ctx = NSI.DeclCtx;
4171  const Type *NSType = NSI.NameSpecifier->getAsType();
4172 
4173  // If the current NestedNameSpecifier refers to a class and the
4174  // current correction candidate is the name of that class, then skip
4175  // it as it is unlikely a qualified version of the class' constructor
4176  // is an appropriate correction.
4177  if (CXXRecordDecl *NSDecl = NSType ? NSType->getAsCXXRecordDecl() :
4178  nullptr) {
4179  if (NSDecl->getIdentifier() == QR.getCorrectionAsIdentifierInfo())
4180  continue;
4181  }
4182 
4183  TypoCorrection TC(QR);
4184  TC.ClearCorrectionDecls();
4185  TC.setCorrectionSpecifier(NSI.NameSpecifier);
4186  TC.setQualifierDistance(NSI.EditDistance);
4187  TC.setCallbackDistance(0); // Reset the callback distance
4188 
4189  // If the current correction candidate and namespace combination are
4190  // too far away from the original typo based on the normalized edit
4191  // distance, then skip performing a qualified name lookup.
4192  unsigned TmpED = TC.getEditDistance(true);
4193  if (QR.getCorrectionAsIdentifierInfo() != Typo && TmpED &&
4194  TypoLen / TmpED < 3)
4195  continue;
4196 
4197  Result.clear();
4198  Result.setLookupName(QR.getCorrectionAsIdentifierInfo());
4199  if (!SemaRef.LookupQualifiedName(Result, Ctx))
4200  continue;
4201 
4202  // Any corrections added below will be validated in subsequent
4203  // iterations of the main while() loop over the Consumer's contents.
4204  switch (Result.getResultKind()) {
4205  case LookupResult::Found:
4207  if (SS && SS->isValid()) {
4208  std::string NewQualified = TC.getAsString(SemaRef.getLangOpts());
4209  std::string OldQualified;
4210  llvm::raw_string_ostream OldOStream(OldQualified);
4211  SS->getScopeRep()->print(OldOStream, SemaRef.getPrintingPolicy());
4212  OldOStream << Typo->getName();
4213  // If correction candidate would be an identical written qualified
4214  // identifer, then the existing CXXScopeSpec probably included a
4215  // typedef that didn't get accounted for properly.
4216  if (OldOStream.str() == NewQualified)
4217  break;
4218  }
4219  for (LookupResult::iterator TRD = Result.begin(), TRDEnd = Result.end();
4220  TRD != TRDEnd; ++TRD) {
4221  if (SemaRef.CheckMemberAccess(TC.getCorrectionRange().getBegin(),
4222  NSType ? NSType->getAsCXXRecordDecl()
4223  : nullptr,
4224  TRD.getPair()) == Sema::AR_accessible)
4225  TC.addCorrectionDecl(*TRD);
4226  }
4227  if (TC.isResolved()) {
4228  TC.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
4229  addCorrection(TC);
4230  }
4231  break;
4232  }
4237  break;
4238  }
4239  }
4240  }
4241  QualifiedResults.clear();
4242 }
4243 
4244 TypoCorrectionConsumer::NamespaceSpecifierSet::NamespaceSpecifierSet(
4245  ASTContext &Context, DeclContext *CurContext, CXXScopeSpec *CurScopeSpec)
4246  : Context(Context), CurContextChain(buildContextChain(CurContext)) {
4247  if (NestedNameSpecifier *NNS =
4248  CurScopeSpec ? CurScopeSpec->getScopeRep() : nullptr) {
4249  llvm::raw_string_ostream SpecifierOStream(CurNameSpecifier);
4250  NNS->print(SpecifierOStream, Context.getPrintingPolicy());
4251 
4252  getNestedNameSpecifierIdentifiers(NNS, CurNameSpecifierIdentifiers);
4253  }
4254  // Build the list of identifiers that would be used for an absolute
4255  // (from the global context) NestedNameSpecifier referring to the current
4256  // context.
4257  for (DeclContext *C : llvm::reverse(CurContextChain)) {
4258  if (auto *ND = dyn_cast_or_null<NamespaceDecl>(C))
4259  CurContextIdentifiers.push_back(ND->getIdentifier());
4260  }
4261 
4262  // Add the global context as a NestedNameSpecifier
4263  SpecifierInfo SI = {cast<DeclContext>(Context.getTranslationUnitDecl()),
4265  DistanceMap[1].push_back(SI);
4266 }
4267 
4268 auto TypoCorrectionConsumer::NamespaceSpecifierSet::buildContextChain(
4269  DeclContext *Start) -> DeclContextList {
4270  assert(Start && "Building a context chain from a null context");
4271  DeclContextList Chain;
4272  for (DeclContext *DC = Start->getPrimaryContext(); DC != nullptr;
4273  DC = DC->getLookupParent()) {
4274  NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(DC);
4275  if (!DC->isInlineNamespace() && !DC->isTransparentContext() &&
4276  !(ND && ND->isAnonymousNamespace()))
4277  Chain.push_back(DC->getPrimaryContext());
4278  }
4279  return Chain;
4280 }
4281 
4282 unsigned
4283 TypoCorrectionConsumer::NamespaceSpecifierSet::buildNestedNameSpecifier(
4284  DeclContextList &DeclChain, NestedNameSpecifier *&NNS) {
4285  unsigned NumSpecifiers = 0;
4286  for (DeclContext *C : llvm::reverse(DeclChain)) {
4287  if (auto *ND = dyn_cast_or_null<NamespaceDecl>(C)) {
4288  NNS = NestedNameSpecifier::Create(Context, NNS, ND);
4289  ++NumSpecifiers;
4290  } else if (auto *RD = dyn_cast_or_null<RecordDecl>(C)) {
4291  NNS = NestedNameSpecifier::Create(Context, NNS, RD->isTemplateDecl(),
4292  RD->getTypeForDecl());
4293  ++NumSpecifiers;
4294  }
4295  }
4296  return NumSpecifiers;
4297 }
4298 
4299 void TypoCorrectionConsumer::NamespaceSpecifierSet::addNameSpecifier(
4300  DeclContext *Ctx) {
4301  NestedNameSpecifier *NNS = nullptr;
4302  unsigned NumSpecifiers = 0;
4303  DeclContextList NamespaceDeclChain(buildContextChain(Ctx));
4304  DeclContextList FullNamespaceDeclChain(NamespaceDeclChain);
4305 
4306  // Eliminate common elements from the two DeclContext chains.
4307  for (DeclContext *C : llvm::reverse(CurContextChain)) {
4308  if (NamespaceDeclChain.empty() || NamespaceDeclChain.back() != C)
4309  break;
4310  NamespaceDeclChain.pop_back();
4311  }
4312 
4313  // Build the NestedNameSpecifier from what is left of the NamespaceDeclChain
4314  NumSpecifiers = buildNestedNameSpecifier(NamespaceDeclChain, NNS);
4315 
4316  // Add an explicit leading '::' specifier if needed.
4317  if (NamespaceDeclChain.empty()) {
4318  // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
4319  NNS = NestedNameSpecifier::GlobalSpecifier(Context);
4320  NumSpecifiers =
4321  buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
4322  } else if (NamedDecl *ND =
4323  dyn_cast_or_null<NamedDecl>(NamespaceDeclChain.back())) {
4324  IdentifierInfo *Name = ND->getIdentifier();
4325  bool SameNameSpecifier = false;
4326  if (std::find(CurNameSpecifierIdentifiers.begin(),
4327  CurNameSpecifierIdentifiers.end(),
4328  Name) != CurNameSpecifierIdentifiers.end()) {
4329  std::string NewNameSpecifier;
4330  llvm::raw_string_ostream SpecifierOStream(NewNameSpecifier);
4331  SmallVector<const IdentifierInfo *, 4> NewNameSpecifierIdentifiers;
4332  getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
4333  NNS->print(SpecifierOStream, Context.getPrintingPolicy());
4334  SpecifierOStream.flush();
4335  SameNameSpecifier = NewNameSpecifier == CurNameSpecifier;
4336  }
4337  if (SameNameSpecifier ||
4338  std::find(CurContextIdentifiers.begin(), CurContextIdentifiers.end(),
4339  Name) != CurContextIdentifiers.end()) {
4340  // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
4341  NNS = NestedNameSpecifier::GlobalSpecifier(Context);
4342  NumSpecifiers =
4343  buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
4344  }
4345  }
4346 
4347  // If the built NestedNameSpecifier would be replacing an existing
4348  // NestedNameSpecifier, use the number of component identifiers that
4349  // would need to be changed as the edit distance instead of the number
4350  // of components in the built NestedNameSpecifier.
4351  if (NNS && !CurNameSpecifierIdentifiers.empty()) {
4352  SmallVector<const IdentifierInfo*, 4> NewNameSpecifierIdentifiers;
4353  getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
4354  NumSpecifiers = llvm::ComputeEditDistance(
4355  llvm::makeArrayRef(CurNameSpecifierIdentifiers),
4356  llvm::makeArrayRef(NewNameSpecifierIdentifiers));
4357  }
4358 
4359  SpecifierInfo SI = {Ctx, NNS, NumSpecifiers};
4360  DistanceMap[NumSpecifiers].push_back(SI);
4361 }
4362 
4363 /// Perform name lookup for a possible result for typo correction.
4364 static void LookupPotentialTypoResult(Sema &SemaRef,
4365  LookupResult &Res,
4366  IdentifierInfo *Name,
4367  Scope *S, CXXScopeSpec *SS,
4368  DeclContext *MemberContext,
4369  bool EnteringContext,
4370  bool isObjCIvarLookup,
4371  bool FindHidden) {
4372  Res.suppressDiagnostics();
4373  Res.clear();
4374  Res.setLookupName(Name);
4375  Res.setAllowHidden(FindHidden);
4376  if (MemberContext) {
4377  if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(MemberContext)) {
4378  if (isObjCIvarLookup) {
4379  if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(Name)) {
4380  Res.addDecl(Ivar);
4381  Res.resolveKind();
4382  return;
4383  }
4384  }
4385 
4386  if (ObjCPropertyDecl *Prop = Class->FindPropertyDeclaration(
4388  Res.addDecl(Prop);
4389  Res.resolveKind();
4390  return;
4391  }
4392  }
4393 
4394  SemaRef.LookupQualifiedName(Res, MemberContext);
4395  return;
4396  }
4397 
4398  SemaRef.LookupParsedName(Res, S, SS, /*AllowBuiltinCreation=*/false,
4399  EnteringContext);
4400 
4401  // Fake ivar lookup; this should really be part of
4402  // LookupParsedName.
4403  if (ObjCMethodDecl *Method = SemaRef.getCurMethodDecl()) {
4404  if (Method->isInstanceMethod() && Method->getClassInterface() &&
4405  (Res.empty() ||
4406  (Res.isSingleResult() &&
4408  if (ObjCIvarDecl *IV
4409  = Method->getClassInterface()->lookupInstanceVariable(Name)) {
4410  Res.addDecl(IV);
4411  Res.resolveKind();
4412  }
4413  }
4414  }
4415 }
4416 
4417 /// Add keywords to the consumer as possible typo corrections.
4418 static void AddKeywordsToConsumer(Sema &SemaRef,
4419  TypoCorrectionConsumer &Consumer,
4421  bool AfterNestedNameSpecifier) {
4422  if (AfterNestedNameSpecifier) {
4423  // For 'X::', we know exactly which keywords can appear next.
4424  Consumer.addKeywordResult("template");
4425  if (CCC.WantExpressionKeywords)
4426  Consumer.addKeywordResult("operator");
4427  return;
4428  }
4429 
4430  if (CCC.WantObjCSuper)
4431  Consumer.addKeywordResult("super");
4432 
4433  if (CCC.WantTypeSpecifiers) {
4434  // Add type-specifier keywords to the set of results.
4435  static const char *const CTypeSpecs[] = {
4436  "char", "const", "double", "enum", "float", "int", "long", "short",
4437  "signed", "struct", "union", "unsigned", "void", "volatile",
4438  "_Complex", "_Imaginary",
4439  // storage-specifiers as well
4440  "extern", "inline", "static", "typedef"
4441  };
4442 
4443  const unsigned NumCTypeSpecs = llvm::array_lengthof(CTypeSpecs);
4444  for (unsigned I = 0; I != NumCTypeSpecs; ++I)
4445  Consumer.addKeywordResult(CTypeSpecs[I]);
4446 
4447  if (SemaRef.getLangOpts().C99)
4448  Consumer.addKeywordResult("restrict");
4449  if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus)
4450  Consumer.addKeywordResult("bool");
4451  else if (SemaRef.getLangOpts().C99)
4452  Consumer.addKeywordResult("_Bool");
4453 
4454  if (SemaRef.getLangOpts().CPlusPlus) {
4455  Consumer.addKeywordResult("class");
4456  Consumer.addKeywordResult("typename");
4457  Consumer.addKeywordResult("wchar_t");
4458 
4459  if (SemaRef.getLangOpts().CPlusPlus11) {
4460  Consumer.addKeywordResult("char16_t");
4461  Consumer.addKeywordResult("char32_t");
4462  Consumer.addKeywordResult("constexpr");
4463  Consumer.addKeywordResult("decltype");
4464  Consumer.addKeywordResult("thread_local");
4465  }
4466  }
4467 
4468  if (SemaRef.getLangOpts().GNUKeywords)
4469  Consumer.addKeywordResult("typeof");
4470  } else if (CCC.WantFunctionLikeCasts) {
4471  static const char *const CastableTypeSpecs[] = {
4472  "char", "double", "float", "int", "long", "short",
4473  "signed", "unsigned", "void"
4474  };
4475  for (auto *kw : CastableTypeSpecs)
4476  Consumer.addKeywordResult(kw);
4477  }
4478 
4479  if (CCC.WantCXXNamedCasts && SemaRef.getLangOpts().CPlusPlus) {
4480  Consumer.addKeywordResult("const_cast");
4481  Consumer.addKeywordResult("dynamic_cast");
4482  Consumer.addKeywordResult("reinterpret_cast");
4483  Consumer.addKeywordResult("static_cast");
4484  }
4485 
4486  if (CCC.WantExpressionKeywords) {
4487  Consumer.addKeywordResult("sizeof");
4488  if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus) {
4489  Consumer.addKeywordResult("false");
4490  Consumer.addKeywordResult("true");
4491  }
4492 
4493  if (SemaRef.getLangOpts().CPlusPlus) {
4494  static const char *const CXXExprs[] = {
4495  "delete", "new", "operator", "throw", "typeid"
4496  };
4497  const unsigned NumCXXExprs = llvm::array_lengthof(CXXExprs);
4498  for (unsigned I = 0; I != NumCXXExprs; ++I)
4499  Consumer.addKeywordResult(CXXExprs[I]);
4500 
4501  if (isa<CXXMethodDecl>(SemaRef.CurContext) &&
4502  cast<CXXMethodDecl>(SemaRef.CurContext)->isInstance())
4503  Consumer.addKeywordResult("this");
4504 
4505  if (SemaRef.getLangOpts().CPlusPlus11) {
4506  Consumer.addKeywordResult("alignof");
4507  Consumer.addKeywordResult("nullptr");
4508  }
4509  }
4510 
4511  if (SemaRef.getLangOpts().C11) {
4512  // FIXME: We should not suggest _Alignof if the alignof macro
4513  // is present.
4514  Consumer.addKeywordResult("_Alignof");
4515  }
4516  }
4517 
4518  if (CCC.WantRemainingKeywords) {
4519  if (SemaRef.getCurFunctionOrMethodDecl() || SemaRef.getCurBlock()) {
4520  // Statements.
4521  static const char *const CStmts[] = {
4522  "do", "else", "for", "goto", "if", "return", "switch", "while" };
4523  const unsigned NumCStmts = llvm::array_lengthof(CStmts);
4524  for (unsigned I = 0; I != NumCStmts; ++I)
4525  Consumer.addKeywordResult(CStmts[I]);
4526 
4527  if (SemaRef.getLangOpts().CPlusPlus) {
4528  Consumer.addKeywordResult("catch");
4529  Consumer.addKeywordResult("try");
4530  }
4531 
4532  if (S && S->getBreakParent())
4533  Consumer.addKeywordResult("break");
4534 
4535  if (S && S->getContinueParent())
4536  Consumer.addKeywordResult("continue");
4537 
4538  if (SemaRef.getCurFunction() &&
4539  !SemaRef.getCurFunction()->SwitchStack.empty()) {
4540  Consumer.addKeywordResult("case");
4541  Consumer.addKeywordResult("default");
4542  }
4543  } else {
4544  if (SemaRef.getLangOpts().CPlusPlus) {
4545  Consumer.addKeywordResult("namespace");
4546  Consumer.addKeywordResult("template");
4547  }
4548 
4549  if (S && S->isClassScope()) {
4550  Consumer.addKeywordResult("explicit");
4551  Consumer.addKeywordResult("friend");
4552  Consumer.addKeywordResult("mutable");
4553  Consumer.addKeywordResult("private");
4554  Consumer.addKeywordResult("protected");
4555  Consumer.addKeywordResult("public");
4556  Consumer.addKeywordResult("virtual");
4557  }
4558  }
4559 
4560  if (SemaRef.getLangOpts().CPlusPlus) {
4561  Consumer.addKeywordResult("using");
4562 
4563  if (SemaRef.getLangOpts().CPlusPlus11)
4564  Consumer.addKeywordResult("static_assert");
4565  }
4566  }
4567 }
4568 
4569 std::unique_ptr<TypoCorrectionConsumer> Sema::makeTypoCorrectionConsumer(
4570  const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
4571  Scope *S, CXXScopeSpec *SS,
4572  std::unique_ptr<CorrectionCandidateCallback> CCC,
4573  DeclContext *MemberContext, bool EnteringContext,
4574  const ObjCObjectPointerType *OPT, bool ErrorRecovery) {
4575 
4576  if (Diags.hasFatalErrorOccurred() || !getLangOpts().SpellChecking ||
4577  DisableTypoCorrection)
4578  return nullptr;
4579 
4580  // In Microsoft mode, don't perform typo correction in a template member
4581  // function dependent context because it interferes with the "lookup into
4582  // dependent bases of class templates" feature.
4583  if (getLangOpts().MSVCCompat && CurContext->isDependentContext() &&
4584  isa<CXXMethodDecl>(CurContext))
4585  return nullptr;
4586 
4587  // We only attempt to correct typos for identifiers.
4588  IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4589  if (!Typo)
4590  return nullptr;
4591 
4592  // If the scope specifier itself was invalid, don't try to correct
4593  // typos.
4594  if (SS && SS->isInvalid())
4595  return nullptr;
4596 
4597  // Never try to correct typos during any kind of code synthesis.
4598  if (!CodeSynthesisContexts.empty())
4599  return nullptr;
4600 
4601  // Don't try to correct 'super'.
4602  if (S && S->isInObjcMethodScope() && Typo == getSuperIdentifier())
4603  return nullptr;
4604 
4605  // Abort if typo correction already failed for this specific typo.
4606  IdentifierSourceLocations::iterator locs = TypoCorrectionFailures.find(Typo);
4607  if (locs != TypoCorrectionFailures.end() &&
4608  locs->second.count(TypoName.getLoc()))
4609  return nullptr;
4610 
4611  // Don't try to correct the identifier "vector" when in AltiVec mode.
4612  // TODO: Figure out why typo correction misbehaves in this case, fix it, and
4613  // remove this workaround.
4614  if ((getLangOpts().AltiVec || getLangOpts().ZVector) && Typo->isStr("vector"))
4615  return nullptr;
4616 
4617  // Provide a stop gap for files that are just seriously broken. Trying
4618  // to correct all typos can turn into a HUGE performance penalty, causing
4619  // some files to take minutes to get rejected by the parser.
4620  unsigned Limit = getDiagnostics().getDiagnosticOptions().SpellCheckingLimit;
4621  if (Limit && TyposCorrected >= Limit)
4622  return nullptr;
4623  ++TyposCorrected;
4624 
4625  // If we're handling a missing symbol error, using modules, and the
4626  // special search all modules option is used, look for a missing import.
4627  if (ErrorRecovery && getLangOpts().Modules &&
4628  getLangOpts().ModulesSearchAll) {
4629  // The following has the side effect of loading the missing module.
4630  getModuleLoader().lookupMissingImports(Typo->getName(),
4631  TypoName.getLocStart());
4632  }
4633 
4634  CorrectionCandidateCallback &CCCRef = *CCC;
4635  auto Consumer = llvm::make_unique<TypoCorrectionConsumer>(
4636  *this, TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4637  EnteringContext);
4638 
4639  // Perform name lookup to find visible, similarly-named entities.
4640  bool IsUnqualifiedLookup = false;
4641  DeclContext *QualifiedDC = MemberContext;
4642  if (MemberContext) {
4643  LookupVisibleDecls(MemberContext, LookupKind, *Consumer);
4644 
4645  // Look in qualified interfaces.
4646  if (OPT) {
4647  for (auto *I : OPT->quals())
4648  LookupVisibleDecls(I, LookupKind, *Consumer);
4649  }
4650  } else if (SS && SS->isSet()) {
4651  QualifiedDC = computeDeclContext(*SS, EnteringContext);
4652  if (!QualifiedDC)
4653  return nullptr;
4654 
4655  LookupVisibleDecls(QualifiedDC, LookupKind, *Consumer);
4656  } else {
4657  IsUnqualifiedLookup = true;
4658  }
4659 
4660  // Determine whether we are going to search in the various namespaces for
4661  // corrections.
4662  bool SearchNamespaces
4663  = getLangOpts().CPlusPlus &&
4664  (IsUnqualifiedLookup || (SS && SS->isSet()));
4665 
4666  if (IsUnqualifiedLookup || SearchNamespaces) {
4667  // For unqualified lookup, look through all of the names that we have
4668  // seen in this translation unit.
4669  // FIXME: Re-add the ability to skip very unlikely potential corrections.
4670  for (const auto &I : Context.Idents)
4671  Consumer->FoundName(I.getKey());
4672 
4673  // Walk through identifiers in external identifier sources.
4674  // FIXME: Re-add the ability to skip very unlikely potential corrections.
4675  if (IdentifierInfoLookup *External
4676  = Context.Idents.getExternalIdentifierLookup()) {
4677  std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
4678  do {
4679  StringRef Name = Iter->Next();
4680  if (Name.empty())
4681  break;
4682 
4683  Consumer->FoundName(Name);
4684  } while (true);
4685  }
4686  }
4687 
4688  AddKeywordsToConsumer(*this, *Consumer, S, CCCRef, SS && SS->isNotEmpty());
4689 
4690  // Build the NestedNameSpecifiers for the KnownNamespaces, if we're going
4691  // to search those namespaces.
4692  if (SearchNamespaces) {
4693  // Load any externally-known namespaces.
4694  if (ExternalSource && !LoadedExternalKnownNamespaces) {
4695  SmallVector<NamespaceDecl *, 4> ExternalKnownNamespaces;
4696  LoadedExternalKnownNamespaces = true;
4697  ExternalSource->ReadKnownNamespaces(ExternalKnownNamespaces);
4698  for (auto *N : ExternalKnownNamespaces)
4699  KnownNamespaces[N] = true;
4700  }
4701 
4702  Consumer->addNamespaces(KnownNamespaces);
4703  }
4704 
4705  return Consumer;
4706 }
4707 
4708 /// Try to "correct" a typo in the source code by finding
4709 /// visible declarations whose names are similar to the name that was
4710 /// present in the source code.
4711 ///
4712 /// \param TypoName the \c DeclarationNameInfo structure that contains
4713 /// the name that was present in the source code along with its location.
4714 ///
4715 /// \param LookupKind the name-lookup criteria used to search for the name.
4716 ///
4717 /// \param S the scope in which name lookup occurs.
4718 ///
4719 /// \param SS the nested-name-specifier that precedes the name we're
4720 /// looking for, if present.
4721 ///
4722 /// \param CCC A CorrectionCandidateCallback object that provides further
4723 /// validation of typo correction candidates. It also provides flags for
4724 /// determining the set of keywords permitted.
4725 ///
4726 /// \param MemberContext if non-NULL, the context in which to look for
4727 /// a member access expression.
4728 ///
4729 /// \param EnteringContext whether we're entering the context described by
4730 /// the nested-name-specifier SS.
4731 ///
4732 /// \param OPT when non-NULL, the search for visible declarations will
4733 /// also walk the protocols in the qualified interfaces of \p OPT.
4734 ///
4735 /// \returns a \c TypoCorrection containing the corrected name if the typo
4736 /// along with information such as the \c NamedDecl where the corrected name
4737 /// was declared, and any additional \c NestedNameSpecifier needed to access
4738 /// it (C++ only). The \c TypoCorrection is empty if there is no correction.
4740  Sema::LookupNameKind LookupKind,
4741  Scope *S, CXXScopeSpec *SS,
4742  std::unique_ptr<CorrectionCandidateCallback> CCC,
4743  CorrectTypoKind Mode,
4744  DeclContext *MemberContext,
4745  bool EnteringContext,
4746  const ObjCObjectPointerType *OPT,
4747  bool RecordFailure) {
4748  assert(CCC && "CorrectTypo requires a CorrectionCandidateCallback");
4749 
4750  // Always let the ExternalSource have the first chance at correction, even
4751  // if we would otherwise have given up.
4752  if (ExternalSource) {
4753  if (TypoCorrection Correction = ExternalSource->CorrectTypo(
4754  TypoName, LookupKind, S, SS, *CCC, MemberContext, EnteringContext, OPT))
4755  return Correction;
4756  }
4757 
4758  // Ugly hack equivalent to CTC == CTC_ObjCMessageReceiver;
4759  // WantObjCSuper is only true for CTC_ObjCMessageReceiver and for
4760  // some instances of CTC_Unknown, while WantRemainingKeywords is true
4761  // for CTC_Unknown but not for CTC_ObjCMessageReceiver.
4762  bool ObjCMessageReceiver = CCC->WantObjCSuper && !CCC->WantRemainingKeywords;
4763 
4764  IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4765  auto Consumer = makeTypoCorrectionConsumer(
4766  TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4767  EnteringContext, OPT, Mode == CTK_ErrorRecovery);
4768 
4769  if (!Consumer)
4770  return TypoCorrection();
4771 
4772  // If we haven't found anything, we're done.
4773  if (Consumer->empty())
4774  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4775 
4776  // Make sure the best edit distance (prior to adding any namespace qualifiers)
4777  // is not more that about a third of the length of the typo's identifier.
4778  unsigned ED = Consumer->getBestEditDistance(true);
4779  unsigned TypoLen = Typo->getName().size();
4780  if (ED > 0 && TypoLen / ED < 3)
4781  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4782 
4783  TypoCorrection BestTC = Consumer->getNextCorrection();
4784  TypoCorrection SecondBestTC = Consumer->getNextCorrection();
4785  if (!BestTC)
4786  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4787 
4788  ED = BestTC.getEditDistance();
4789 
4790  if (TypoLen >= 3 && ED > 0 && TypoLen / ED < 3) {
4791  // If this was an unqualified lookup and we believe the callback
4792  // object wouldn't have filtered out possible corrections, note
4793  // that no correction was found.
4794  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4795  }
4796 
4797  // If only a single name remains, return that result.
4798  if (!SecondBestTC ||
4799  SecondBestTC.getEditDistance(false) > BestTC.getEditDistance(false)) {
4800  const TypoCorrection &Result = BestTC;
4801 
4802  // Don't correct to a keyword that's the same as the typo; the keyword
4803  // wasn't actually in scope.
4804  if (ED == 0 && Result.isKeyword())
4805  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4806 
4807  TypoCorrection TC = Result;
4808  TC.setCorrectionRange(SS, TypoName);
4809  checkCorrectionVisibility(*this, TC);
4810  return TC;
4811  } else if (SecondBestTC && ObjCMessageReceiver) {
4812  // Prefer 'super' when we're completing in a message-receiver
4813  // context.
4814 
4815  if (BestTC.getCorrection().getAsString() != "super") {
4816  if (SecondBestTC.getCorrection().getAsString() == "super")
4817  BestTC = SecondBestTC;
4818  else if ((*Consumer)["super"].front().isKeyword())
4819  BestTC = (*Consumer)["super"].front();
4820  }
4821  // Don't correct to a keyword that's the same as the typo; the keyword
4822  // wasn't actually in scope.
4823  if (BestTC.getEditDistance() == 0 ||
4824  BestTC.getCorrection().getAsString() != "super")
4825  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4826 
4827  BestTC.setCorrectionRange(SS, TypoName);
4828  return BestTC;
4829  }
4830 
4831  // Record the failure's location if needed and return an empty correction. If
4832  // this was an unqualified lookup and we believe the callback object did not
4833  // filter out possible corrections, also cache the failure for the typo.
4834  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure && !SecondBestTC);
4835 }
4836 
4837 /// Try to "correct" a typo in the source code by finding
4838 /// visible declarations whose names are similar to the name that was
4839 /// present in the source code.
4840 ///
4841 /// \param TypoName the \c DeclarationNameInfo structure that contains
4842 /// the name that was present in the source code along with its location.
4843 ///
4844 /// \param LookupKind the name-lookup criteria used to search for the name.
4845 ///
4846 /// \param S the scope in which name lookup occurs.
4847 ///
4848 /// \param SS the nested-name-specifier that precedes the name we're
4849 /// looking for, if present.
4850 ///
4851 /// \param CCC A CorrectionCandidateCallback object that provides further
4852 /// validation of typo correction candidates. It also provides flags for
4853 /// determining the set of keywords permitted.
4854 ///
4855 /// \param TDG A TypoDiagnosticGenerator functor that will be used to print
4856 /// diagnostics when the actual typo correction is attempted.
4857 ///
4858 /// \param TRC A TypoRecoveryCallback functor that will be used to build an
4859 /// Expr from a typo correction candidate.
4860 ///
4861 /// \param MemberContext if non-NULL, the context in which to look for
4862 /// a member access expression.
4863 ///
4864 /// \param EnteringContext whether we're entering the context described by
4865 /// the nested-name-specifier SS.
4866 ///
4867 /// \param OPT when non-NULL, the search for visible declarations will
4868 /// also walk the protocols in the qualified interfaces of \p OPT.
4869 ///
4870 /// \returns a new \c TypoExpr that will later be replaced in the AST with an
4871 /// Expr representing the result of performing typo correction, or nullptr if
4872 /// typo correction is not possible. If nullptr is returned, no diagnostics will
4873 /// be emitted and it is the responsibility of the caller to emit any that are
4874 /// needed.
4876  const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
4877  Scope *S, CXXScopeSpec *SS,
4878  std::unique_ptr<CorrectionCandidateCallback> CCC,
4880  DeclContext *MemberContext, bool EnteringContext,
4881  const ObjCObjectPointerType *OPT) {
4882  assert(CCC && "CorrectTypoDelayed requires a CorrectionCandidateCallback");
4883 
4884  auto Consumer = makeTypoCorrectionConsumer(
4885  TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4886  EnteringContext, OPT, Mode == CTK_ErrorRecovery);
4887 
4888  // Give the external sema source a chance to correct the typo.
4889  TypoCorrection ExternalTypo;
4890  if (ExternalSource && Consumer) {
4891  ExternalTypo = ExternalSource->CorrectTypo(
4892  TypoName, LookupKind, S, SS, *Consumer->getCorrectionValidator(),
4893  MemberContext, EnteringContext, OPT);
4894  if (ExternalTypo)
4895  Consumer->addCorrection(ExternalTypo);
4896  }
4897 
4898  if (!Consumer || Consumer->empty())
4899  return nullptr;
4900 
4901  // Make sure the best edit distance (prior to adding any namespace qualifiers)
4902  // is not more that about a third of the length of the typo's identifier.
4903  unsigned ED = Consumer->getBestEditDistance(true);
4904  IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4905  if (!ExternalTypo && ED > 0 && Typo->getName().size() / ED < 3)
4906  return nullptr;
4907 
4908  ExprEvalContexts.back().NumTypos++;
4909  return createDelayedTypo(std::move(Consumer), std::move(TDG), std::move(TRC));
4910 }
4911 
4913  if (!CDecl) return;
4914 
4915  if (isKeyword())
4916  CorrectionDecls.clear();
4917 
4918  CorrectionDecls.push_back(CDecl);
4919 
4920  if (!CorrectionName)
4921  CorrectionName = CDecl->getDeclName();
4922 }
4923 
4924 std::string TypoCorrection::getAsString(const LangOptions &LO) const {
4925  if (CorrectionNameSpec) {
4926  std::string tmpBuffer;
4927  llvm::raw_string_ostream PrefixOStream(tmpBuffer);
4928  CorrectionNameSpec->print(PrefixOStream, PrintingPolicy(LO));
4929  PrefixOStream << CorrectionName;
4930  return PrefixOStream.str();
4931  }
4932 
4933  return CorrectionName.getAsString();
4934 }
4935 
4937  const TypoCorrection &candidate) {
4938  if (!candidate.isResolved())
4939  return true;
4940 
4941  if (candidate.isKeyword())
4942  return WantTypeSpecifiers || WantExpressionKeywords || WantCXXNamedCasts ||
4943  WantRemainingKeywords || WantObjCSuper;
4944 
4945  bool HasNonType = false;
4946  bool HasStaticMethod = false;
4947  bool HasNonStaticMethod = false;
4948  for (Decl *D : candidate) {
4949  if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(D))
4950  D = FTD->getTemplatedDecl();
4951  if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
4952  if (Method->isStatic())
4953  HasStaticMethod = true;
4954  else
4955  HasNonStaticMethod = true;
4956  }
4957  if (!isa<TypeDecl>(D))
4958  HasNonType = true;
4959  }
4960 
4961  if (IsAddressOfOperand && HasNonStaticMethod && !HasStaticMethod &&
4962  !candidate.getCorrectionSpecifier())
4963  return false;
4964 
4965  return WantTypeSpecifiers || HasNonType;
4966 }
4967 
4969  bool HasExplicitTemplateArgs,
4970  MemberExpr *ME)
4971  : NumArgs(NumArgs), HasExplicitTemplateArgs(HasExplicitTemplateArgs),
4972  CurContext(SemaRef.CurContext), MemberFn(ME) {
4973  WantTypeSpecifiers = false;
4974  WantFunctionLikeCasts = SemaRef.getLangOpts().CPlusPlus && NumArgs == 1;
4975  WantRemainingKeywords = false;
4976 }
4977 
4979  if (!candidate.getCorrectionDecl())
4980  return candidate.isKeyword();
4981 
4982  for (auto *C : candidate) {
4983  FunctionDecl *FD = nullptr;
4984  NamedDecl *ND = C->getUnderlyingDecl();
4985  if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
4986  FD = FTD->getTemplatedDecl();
4987  if (!HasExplicitTemplateArgs && !FD) {
4988  if (!(FD = dyn_cast<FunctionDecl>(ND)) && isa<ValueDecl>(ND)) {
4989  // If the Decl is neither a function nor a template function,
4990  // determine if it is a pointer or reference to a function. If so,
4991  // check against the number of arguments expected for the pointee.
4992  QualType ValType = cast<ValueDecl>(ND)->getType();
4993  if (ValType->isAnyPointerType() || ValType->isReferenceType())
4994  ValType = ValType->getPointeeType();
4995  if (const FunctionProtoType *FPT = ValType->getAs<FunctionProtoType>())
4996  if (FPT->getNumParams() == NumArgs)
4997  return true;
4998  }
4999  }
5000 
5001  // Skip the current candidate if it is not a FunctionDecl or does not accept
5002  // the current number of arguments.
5003  if (!FD || !(FD->getNumParams() >= NumArgs &&
5004  FD->getMinRequiredArguments() <= NumArgs))
5005  continue;
5006 
5007  // If the current candidate is a non-static C++ method, skip the candidate
5008  // unless the method being corrected--or the current DeclContext, if the
5009  // function being corrected is not a method--is a method in the same class
5010  // or a descendent class of the candidate's parent class.
5011  if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5012  if (MemberFn || !MD->isStatic()) {
5013  CXXMethodDecl *CurMD =
5014  MemberFn
5015  ? dyn_cast_or_null<CXXMethodDecl>(MemberFn->getMemberDecl())
5016  : dyn_cast_or_null<CXXMethodDecl>(CurContext);
5017  CXXRecordDecl *CurRD =
5018  CurMD ? CurMD->getParent()->getCanonicalDecl() : nullptr;
5019  CXXRecordDecl *RD = MD->getParent()->getCanonicalDecl();
5020  if (!CurRD || (CurRD != RD && !CurRD->isDerivedFrom(RD)))
5021  continue;
5022  }
5023  }
5024  return true;
5025  }
5026  return false;
5027 }
5028 
5029 void Sema::diagnoseTypo(const TypoCorrection &Correction,
5030  const PartialDiagnostic &TypoDiag,
5031  bool ErrorRecovery) {
5032  diagnoseTypo(Correction, TypoDiag, PDiag(diag::note_previous_decl),
5033  ErrorRecovery);
5034 }
5035 
5036 /// Find which declaration we should import to provide the definition of
5037 /// the given declaration.
5039  if (VarDecl *VD = dyn_cast<VarDecl>(D))
5040  return VD->getDefinition();
5041  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
5042  return FD->getDefinition();
5043  if (TagDecl *TD = dyn_cast<TagDecl>(D))
5044  return TD->getDefinition();
5045  if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(D))
5046  return ID->getDefinition();
5047  if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl>(D))
5048  return PD->getDefinition();
5049  if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
5050  return getDefinitionToImport(TD->getTemplatedDecl());
5051  return nullptr;
5052 }
5053 
5055  MissingImportKind MIK, bool Recover) {
5056  // Suggest importing a module providing the definition of this entity, if
5057  // possible.
5058  NamedDecl *Def = getDefinitionToImport(Decl);
5059  if (!Def)
5060  Def = Decl;
5061 
5062  Module *Owner = getOwningModule(Decl);
5063  assert(Owner && "definition of hidden declaration is not in a module");
5064 
5065  llvm::SmallVector<Module*, 8> OwningModules;
5066  OwningModules.push_back(Owner);
5067  auto Merged = Context.getModulesWithMergedDefinition(Decl);
5068  OwningModules.insert(OwningModules.end(), Merged.begin(), Merged.end());
5069 
5070  diagnoseMissingImport(Loc, Decl, Decl->getLocation(), OwningModules, MIK,
5071  Recover);
5072 }
5073 
5074 /// Get a "quoted.h" or <angled.h> include path to use in a diagnostic
5075 /// suggesting the addition of a #include of the specified file.
5077  const FileEntry *E) {
5078  bool IsSystem;
5079  auto Path =
5081  return (IsSystem ? '<' : '"') + Path + (IsSystem ? '>' : '"');
5082 }
5083 
5085  SourceLocation DeclLoc,
5086  ArrayRef<Module *> Modules,
5087  MissingImportKind MIK, bool Recover) {
5088  assert(!Modules.empty());
5089 
5090  // Weed out duplicates from module list.
5091  llvm::SmallVector<Module*, 8> UniqueModules;
5092  llvm::SmallDenseSet<Module*, 8> UniqueModuleSet;
5093  for (auto *M : Modules)
5094  if (UniqueModuleSet.insert(M).second)
5095  UniqueModules.push_back(M);
5096  Modules = UniqueModules;
5097 
5098  if (Modules.size() > 1) {
5099  std::string ModuleList;
5100  unsigned N = 0;
5101  for (Module *M : Modules) {
5102  ModuleList += "\n ";
5103  if (++N == 5 && N != Modules.size()) {
5104  ModuleList += "[...]";
5105  break;
5106  }
5107  ModuleList += M->getFullModuleName();
5108  }
5109 
5110  Diag(UseLoc, diag::err_module_unimported_use_multiple)
5111  << (int)MIK << Decl << ModuleList;
5112  } else if (const FileEntry *E = PP.getModuleHeaderToIncludeForDiagnostics(
5113  UseLoc, Modules[0], DeclLoc)) {
5114  // The right way to make the declaration visible is to include a header;
5115  // suggest doing so.
5116  //
5117  // FIXME: Find a smart place to suggest inserting a #include, and add
5118  // a FixItHint there.
5119  Diag(UseLoc, diag::err_module_unimported_use_header)
5120  << (int)MIK << Decl << Modules[0]->getFullModuleName()
5121  << getIncludeStringForHeader(PP, E);
5122  } else {
5123  // FIXME: Add a FixItHint that imports the corresponding module.
5124  Diag(UseLoc, diag::err_module_unimported_use)
5125  << (int)MIK << Decl << Modules[0]->getFullModuleName();
5126  }
5127 
5128  unsigned DiagID;
5129  switch (MIK) {
5130  case MissingImportKind::Declaration:
5131  DiagID = diag::note_previous_declaration;
5132  break;
5133  case MissingImportKind::Definition:
5134  DiagID = diag::note_previous_definition;
5135  break;
5136  case MissingImportKind::DefaultArgument:
5137  DiagID = diag::note_default_argument_declared_here;
5138  break;
5139  case MissingImportKind::ExplicitSpecialization:
5140  DiagID = diag::note_explicit_specialization_declared_here;
5141  break;
5142  case MissingImportKind::PartialSpecialization:
5143  DiagID = diag::note_partial_specialization_declared_here;
5144  break;
5145  }
5146  Diag(DeclLoc, DiagID);
5147 
5148  // Try to recover by implicitly importing this module.
5149  if (Recover)
5150  createImplicitModuleImportForErrorRecovery(UseLoc, Modules[0]);
5151 }
5152 
5153 /// Diagnose a successfully-corrected typo. Separated from the correction
5154 /// itself to allow external validation of the result, etc.
5155 ///
5156 /// \param Correction The result of performing typo correction.
5157 /// \param TypoDiag The diagnostic to produce. This will have the corrected
5158 /// string added to it (and usually also a fixit).
5159 /// \param PrevNote A note to use when indicating the location of the entity to
5160 /// which we are correcting. Will have the correction string added to it.
5161 /// \param ErrorRecovery If \c true (the default), the caller is going to
5162 /// recover from the typo as if the corrected string had been typed.
5163 /// In this case, \c PDiag must be an error, and we will attach a fixit
5164 /// to it.
5165 void Sema::diagnoseTypo(const TypoCorrection &Correction,
5166  const PartialDiagnostic &TypoDiag,
5167  const PartialDiagnostic &PrevNote,
5168  bool ErrorRecovery) {
5169  std::string CorrectedStr = Correction.getAsString(getLangOpts());
5170  std::string CorrectedQuotedStr = Correction.getQuoted(getLangOpts());
5172  Correction.getCorrectionRange(), CorrectedStr);
5173 
5174  // Maybe we're just missing a module import.
5175  if (Correction.requiresImport()) {
5176  NamedDecl *Decl = Correction.getFoundDecl();
5177  assert(Decl && "import required but no declaration to import");
5178 
5179  diagnoseMissingImport(Correction.getCorrectionRange().getBegin(), Decl,
5180  MissingImportKind::Declaration, ErrorRecovery);
5181  return;
5182  }
5183 
5184  Diag(Correction.getCorrectionRange().getBegin(), TypoDiag)
5185  << CorrectedQuotedStr << (ErrorRecovery ? FixTypo : FixItHint());
5186 
5187  NamedDecl *ChosenDecl =
5188  Correction.isKeyword() ? nullptr : Correction.getFoundDecl();
5189  if (PrevNote.getDiagID() && ChosenDecl)
5190  Diag(ChosenDecl->getLocation(), PrevNote)
5191  << CorrectedQuotedStr << (ErrorRecovery ? FixItHint() : FixTypo);
5192 
5193  // Add any extra diagnostics.
5194  for (const PartialDiagnostic &PD : Correction.getExtraDiagnostics())
5195  Diag(Correction.getCorrectionRange().getBegin(), PD);
5196 }
5197 
5198 TypoExpr *Sema::createDelayedTypo(std::unique_ptr<TypoCorrectionConsumer> TCC,
5200  TypoRecoveryCallback TRC) {
5201  assert(TCC && "createDelayedTypo requires a valid TypoCorrectionConsumer");
5202  auto TE = new (Context) TypoExpr(Context.DependentTy);
5203  auto &State = DelayedTypos[TE];
5204  State.Consumer = std::move(TCC);
5205  State.DiagHandler = std::move(TDG);
5206  State.RecoveryHandler = std::move(TRC);
5207  return TE;
5208 }
5209 
5210 const Sema::TypoExprState &Sema::getTypoExprState(TypoExpr *TE) const {
5211  auto Entry = DelayedTypos.find(TE);
5212  assert(Entry != DelayedTypos.end() &&
5213  "Failed to get the state for a TypoExpr!");
5214  return Entry->second;
5215 }
5216 
5218  DelayedTypos.erase(TE);
5219 }
5220 
5222  DeclarationNameInfo Name(II, IILoc);
5223  LookupResult R(*this, Name, LookupAnyName, Sema::NotForRedeclaration);
5224  R.suppressDiagnostics();
5225  R.setHideTags(false);
5226  LookupName(R, S);
5227  R.dump();
5228 }
SourceLocation getLoc() const
getLoc - Returns the main location of the declaration name.
Defines the clang::ASTContext interface.
Name lookup results in an ambiguity because multiple definitions of entity that meet the lookup crite...
Definition: Lookup.h:119
Represents a function declaration or definition.
Definition: Decl.h:1714
FunctionCallFilterCCC(Sema &SemaRef, unsigned NumArgs, bool HasExplicitTemplateArgs, MemberExpr *ME=nullptr)
Name lookup found a set of overloaded functions that met the criteria.
Definition: Lookup.h:64
static DiagnosticBuilder Diag(DiagnosticsEngine *Diags, const LangOptions &Features, FullSourceLoc TokLoc, const char *TokBegin, const char *TokRangeBegin, const char *TokRangeEnd, unsigned DiagID)
Produce a diagnostic highlighting some portion of a literal.
bool isForRedeclaration() const
True if this lookup is just looking for an existing declaration.
Definition: Lookup.h:256
SourceRange getCorrectionRange() const
bool isPredefinedLibFunction(unsigned ID) const
Determines whether this builtin is a predefined libc/libm function, such as "malloc", where we know the signature a priori.
Definition: Builtins.h:141
void setOrigin(CXXRecordDecl *Rec)
CXXMethodDecl * getMethod() const
Definition: Sema.h:1041
no exception specification
PointerType - C99 6.7.5.1 - Pointer Declarators.
Definition: Type.h:2375
A (possibly-)qualified type.
Definition: Type.h:655
Simple class containing the result of Sema::CorrectTypo.
base_class_range bases()
Definition: DeclCXX.h:811
ValueDecl * getMemberDecl() const
Retrieve the member declaration to which this expression refers.
Definition: Expr.h:2561
bool hasVisibleDeclarationSlow(const NamedDecl *D, llvm::SmallVectorImpl< Module *> *Modules)
CorrectTypoKind
Definition: Sema.h:3209
virtual unsigned RankCandidate(const TypoCorrection &candidate)
Method used by Sema::CorrectTypo to assign an "edit distance" rank to a candidate (where a lower valu...
static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result, bool QualifiedNameLookup, bool InBaseClass, VisibleDeclConsumer &Consumer, VisibleDeclsRecord &Visited, bool IncludeDependentBases, bool LoadExternal)
Template argument deduction was successful.
Definition: Sema.h:6905
Ordinary name lookup, which finds ordinary names (functions, variables, typedefs, etc...
Definition: Sema.h:2993
DeclarationName getCXXConstructorName(CanQualType Ty)
getCXXConstructorName - Returns the name of a C++ constructor for the given Type. ...
void setLookupName(DeclarationName Name)
Sets the name to look up.
Definition: Lookup.h:246
bool LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation=false)
Perform unqualified name lookup starting from a given scope.
AmbiguityKind getAmbiguityKind() const
Definition: Lookup.h:315
Look up the name of an Objective-C protocol.
Definition: Sema.h:3027
Filter makeFilter()
Create a filter for this result set.
Definition: Lookup.h:671
CXXMethodDecl * LookupMovingAssignment(CXXRecordDecl *Class, unsigned Quals, bool RValueThis, unsigned ThisQuals)
Look up the moving assignment operator for the given class.
FunctionType - C99 6.7.5.3 - Function Declarators.
Definition: Type.h:3148
Provides information about an attempted template argument deduction, whose success or failure was des...
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee...
Definition: Type.cpp:460
void addConst()
Add the const type qualifier to this QualType.
Definition: Type.h:817
Microsoft&#39;s &#39;__super&#39; specifier, stored as a CXXRecordDecl* of the class it appeared in...
void ForceDeclarationOfImplicitMembers(CXXRecordDecl *Class)
Force the declaration of any implicitly-declared members of this class.
Definition: SemaLookup.cpp:727
The template argument is an expression, and we&#39;ve not resolved it to one of the other forms yet...
Definition: TemplateBase.h:87
unsigned size() const
Retrieve the number of template arguments in this template argument list.
Definition: DeclTemplate.h:270
bool isSingleTagDecl() const
Asks if the result is a single tag decl.
Definition: Lookup.h:519
void erase()
Erase the last element returned from this iterator.
Definition: Lookup.h:643
ConstructorInfo getConstructorInfo(NamedDecl *ND)
Definition: Overload.h:983
Decl - This represents one declaration (or definition), e.g.
Definition: DeclBase.h:86
__DEVICE__ long long abs(long long __n)
A reference to a name which we were able to look up during parsing but could not resolve to a specifi...
Definition: ExprCXX.h:2739
NestedNameSpecifier * getPrefix() const
Return the prefix of this nested name specifier.
SmallVectorImpl< NamedDecl * >::iterator decl_iterator
Name lookup results in an ambiguity because multiple nonstatic entities that meet the lookup criteria...
Definition: Lookup.h:104
Defines the C++ template declaration subclasses.
bool LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS, bool AllowBuiltinCreation=false, bool EnteringContext=false)
Performs name lookup for a name that was parsed in the source code, and may contain a C++ scope speci...
StringRef P
Classification Classify(ASTContext &Ctx) const
Classify - Classify this expression according to the C++11 expression taxonomy.
Definition: Expr.h:377
bool isTemplateParamScope() const
isTemplateParamScope - Return true if this scope is a C++ template parameter scope.
Definition: Scope.h:375
Scope * TUScope
Translation Unit Scope - useful to Objective-C actions that need to lookup file scope declarations in...
Definition: Sema.h:805
void swap(CXXBasePaths &Other)
Swap this data structure&#39;s contents with another CXXBasePaths object.
SmallVector< CodeSynthesisContext, 16 > CodeSynthesisContexts
List of active code synthesis contexts.
Definition: Sema.h:7239
static bool hasVisibleDeclarationImpl(Sema &S, const NamedDecl *D, llvm::SmallVectorImpl< Module *> *Modules, Filter F)
Decl * getPreviousDecl()
Retrieve the previous declaration that declares the same entity as this declaration, or NULL if there is no previous declaration.
Definition: DeclBase.h:958
NamedDecl * getDecl() const
The base class of the type hierarchy.
Definition: Type.h:1421
MissingImportKind
Kinds of missing import.
Definition: Sema.h:2085
bool isDerivedFrom(const CXXRecordDecl *Base) const
Determine whether this class is derived from the class Base.
The template argument is a declaration that was provided for a pointer, reference, or pointer to member non-type template parameter.
Definition: TemplateBase.h:64
Represent a C++ namespace.
Definition: Decl.h:514
RedeclarationKind
Specifies whether (or how) name lookup is being performed for a redeclaration (vs.
Definition: Sema.h:3038
Ambiguous candidates found.
Definition: Overload.h:60
decl_iterator begin()
AccessSpecifier
A C++ access specifier (public, private, protected), plus the special value "none" which means differ...
Definition: Specifiers.h:98
const NestedNameSpecifier * Specifier
Look up of a name that precedes the &#39;::&#39; scope resolution operator in C++.
Definition: Sema.h:3009
void makeKeyword()
Mark this TypoCorrection as being a keyword.
bool needsImplicitMoveAssignment() const
Determine whether this class should get an implicit move assignment operator or if any existing speci...
Definition: DeclCXX.h:1152
Scope * getContinueParent()
getContinueParent - Return the closest scope that a continue statement would be affected by...
Definition: Scope.h:239
void setCorrectionSpecifier(NestedNameSpecifier *NNS)
bool hasNext() const
Definition: Lookup.h:628
Represents a path from a specific derived class (which is not represented as part of the path) to a p...
LiteralOperatorLookupResult
The possible outcomes of name lookup for a literal operator.
Definition: Sema.h:3063
unsigned getIdentifierNamespace() const
Definition: DeclBase.h:797
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2463
bool isCompleteDefinition() const
Return true if this decl has its body fully specified.
Definition: Decl.h:3157
lookups_range noload_lookups(bool PreserveInternalState) const
Definition: DeclLookups.h:90
Look up a namespace name within a C++ using directive or namespace alias definition, ignoring non-namespace names (C++ [basic.lookup.udir]p1).
Definition: Sema.h:3013
CXXMethodDecl * DeclareImplicitMoveAssignment(CXXRecordDecl *ClassDecl)
Declare the implicit move assignment operator for the given class.
Consumes visible declarations found when searching for all visible names within a given scope or cont...
Definition: Lookup.h:749
An identifier, stored as an IdentifierInfo*.
CXXConstructorDecl * LookupMovingConstructor(CXXRecordDecl *Class, unsigned Quals)
Look up the moving constructor for the given class.
std::list< CXXBasePath >::iterator paths_iterator
DeclContext::lookup_result Decls
The set of declarations found inside this base class subobject.
static bool LookupBuiltin(Sema &S, LookupResult &R)
Lookup a builtin function, when name lookup would otherwise fail.
Definition: SemaLookup.cpp:674
Represents a variable declaration or definition.
Definition: Decl.h:812
NamedDecl * LazilyCreateBuiltin(IdentifierInfo *II, unsigned ID, Scope *S, bool ForRedeclaration, SourceLocation Loc)
LazilyCreateBuiltin - The specified Builtin-ID was first used at file scope.
Definition: SemaDecl.cpp:1947
CXXMethodDecl * LookupCopyingAssignment(CXXRecordDecl *Class, unsigned Quals, bool RValueThis, unsigned ThisQuals)
Look up the copying assignment operator for the given class.
static NestedNameSpecifier * Create(const ASTContext &Context, NestedNameSpecifier *Prefix, IdentifierInfo *II)
Builds a specifier combining a prefix and an identifier.
SmallVector< SwitchStmt *, 8 > SwitchStack
SwitchStack - This is the current set of active switch statements in the block.
Definition: ScopeInfo.h:180
DeclarationName getLookupName() const
Gets the name to look up.
Definition: Lookup.h:241
QualType getCXXNameType() const
getCXXNameType - If this name is one of the C++ names (of a constructor, destructor, or conversion function), return the type associated with that name.
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:6456
PrintingPolicy getPrintingPolicy() const
Retrieve a suitable printing policy for diagnostics.
Definition: Sema.h:2118
static bool HasOnlyStaticMembers(InputIterator First, InputIterator Last)
Determine whether the given set of member declarations contains only static members, nested types, and enumerators.
bool isInObjcMethodScope() const
isInObjcMethodScope - Return true if this scope is, or is contained in, an Objective-C method body...
Definition: Scope.h:353
Represents an empty template argument, e.g., one that has not been deduced.
Definition: TemplateBase.h:57
Extra information about a function prototype.
Definition: Type.h:3488
static bool CanDeclareSpecialMemberFunction(const CXXRecordDecl *Class)
Determine whether we can declare a special member function within the class at this point...
Definition: SemaLookup.cpp:718
bool needsImplicitCopyAssignment() const
Determine whether this class needs an implicit copy assignment operator to be lazily declared...
Definition: DeclCXX.h:1103
void setNotFoundInCurrentInstantiation()
Note that while no result was found in the current instantiation, there were dependent base classes t...
Definition: Lookup.h:441
ObjCMethodDecl - Represents an instance or class method declaration.
Definition: DeclObjC.h:139
NamedDecl * getUnderlyingDecl()
Looks through UsingDecls and ObjCCompatibleAliasDecls for the underlying named decl.
Definition: Decl.h:431
bool isAmbiguous() const
Definition: Lookup.h:290
static bool FindOMPReductionMember(const CXXBaseSpecifier *Specifier, CXXBasePath &Path, DeclarationName Name)
Base-class lookup callback that determines whether there exists an OpenMP declare reduction member wi...
A namespace, stored as a NamespaceDecl*.
bool isInvalidDecl() const
Definition: DeclBase.h:547
Stores a list of template parameters for a TemplateDecl and its derived classes.
Definition: DeclTemplate.h:68
Describes how types, statements, expressions, and declarations should be printed. ...
Definition: PrettyPrinter.h:38
SpecifierKind getKind() const
Determine what kind of nested name specifier is stored.
Look up an ordinary name that is going to be redeclared as a name with linkage.
Definition: Sema.h:3022
Defines the clang::Expr interface and subclasses for C++ expressions.
void addKeywordResult(StringRef Keyword)
void setMethod(CXXMethodDecl *MD)
Definition: Sema.h:1042
IdentifierInfo * getIdentifier() const
Get the identifier that names this declaration, if there is one.
Definition: Decl.h:269
Types, declared with &#39;struct foo&#39;, typedefs, etc.
Definition: DeclBase.h:130
Represents a struct/union/class.
Definition: Decl.h:3548
bool LookupInSuper(LookupResult &R, CXXRecordDecl *Class)
Perform qualified name lookup into all base classes of the given class.
DeclarationName getDeclName() const
Get the actual, stored name of the declaration, which may be a special name.
Definition: Decl.h:297
bool Encloses(const DeclContext *DC) const
Determine whether this declaration context encloses the declaration context DC.
Definition: DeclBase.cpp:1110
FunctionType::ExtInfo ExtInfo
Definition: Type.h:3489
Represents a class template specialization, which refers to a class template with a given set of temp...
One of these records is kept for each identifier that is lexed.
Name lookup results in an ambiguity; use getAmbiguityKind to figure out what kind of ambiguity we hav...
Definition: Lookup.h:74
bool isStr(const char(&Str)[StrLen]) const
Return true if this is the identifier for the specified string.
std::string getQuoted(const LangOptions &LO) const
Holds long-lived AST nodes (such as types and decls) that can be referred to throughout the semantic ...
Definition: ASTContext.h:150
DeclarationName getCorrection() const
Gets the DeclarationName of the typo correction.
The results of name lookup within a DeclContext.
Definition: DeclBase.h:1188
LineState State
The template argument is an integral value stored in an llvm::APSInt that was provided for an integra...
Definition: TemplateBase.h:72
TemplateDecl * getAsTemplateDecl() const
Retrieve the underlying template declaration that this template name refers to, if known...
Base class for callback objects used by Sema::CorrectTypo to check the validity of a potential typo c...
sema::BlockScopeInfo * getCurBlock()
Retrieve the current block, if any.
Definition: Sema.cpp:1456
void setAmbiguousBaseSubobjectTypes(CXXBasePaths &P)
Make these results show that the name was found in base classes of different types.
Definition: SemaLookup.cpp:646
const Type * getAsType() const
Retrieve the type stored in this nested name specifier.
void FoundDecl(NamedDecl *ND, NamedDecl *Hiding, DeclContext *Ctx, bool InBaseClass) override
Invoked each time Sema::LookupVisibleDecls() finds a declaration visible from the current scope or co...
This declaration is a friend function.
Definition: DeclBase.h:152
void setVisibleDespiteOwningModule()
Set that this declaration is globally visible, even if it came from a module that is not visible...
Definition: DeclBase.h:778
const DeclarationNameInfo & getLookupNameInfo() const
Gets the name info to look up.
Definition: Lookup.h:231
conversion_iterator conversion_end() const
Definition: DeclCXX.h:1257
bool isReferenceType() const
Definition: Type.h:6061
The iterator over UnresolvedSets.
Definition: UnresolvedSet.h:32
void addCorrectionDecl(NamedDecl *CDecl)
Add the given NamedDecl to the list of NamedDecls that are the declarations associated with the Decla...
bool isDefinedOutsideFunctionOrMethod() const
isDefinedOutsideFunctionOrMethod - This predicate returns true if this scoped decl is defined outside...
Definition: DeclBase.h:853
int Category
Definition: Format.cpp:1601
bool Equals(const DeclContext *DC) const
Determine whether this declaration context is equivalent to the declaration context DC...
Definition: DeclBase.h:1461
bool isExternallyDeclarable() const
Determine whether this declaration can be redeclared in a different translation unit.
Definition: Decl.h:385
LookupResultKind getResultKind() const
Definition: Lookup.h:310
Keeps track of the various options that can be enabled, which controls the dialect of C or C++ that i...
Definition: LangOptions.h:50
Scope * getBreakParent()
getBreakParent - Return the closest scope that a break statement would be affected by...
Definition: Scope.h:249
No entity found met the criteria within the current instantiation,, but there were dependent base cla...
Definition: Lookup.h:56
bool requiresImport() const
Returns whether this typo correction is correcting to a declaration that was declared in a module tha...
Describes a module or submodule.
Definition: Module.h:65
IdentifierTable & Idents
Definition: ASTContext.h:538
TemplateDecl * getCXXDeductionGuideTemplate() const
If this name is the name of a C++ deduction guide, return the template associated with that name...
SpecialMemberOverloadResult - The overloading result for a special member function.
Definition: Sema.h:1025
void setCallbackDistance(unsigned ED)
An r-value expression (a pr-value in the C++11 taxonomy) produces a temporary value.
Definition: Specifiers.h:110
DeclClass * getAsSingle() const
Definition: Lookup.h:496
bool isModuleVisible(const Module *M)
Definition: Sema.h:1547
CXXBasePaths * getBasePaths() const
Return the base paths structure that&#39;s associated with these results, or null if none is...
Definition: Lookup.h:332
CXXRecordDecl * getAsRecordDecl() const
Retrieve the record declaration stored in this nested name specifier.
Look up implicit &#39;self&#39; parameter of an objective-c method.
Definition: Sema.h:3029
IdentifierInfo * getAsIdentifier() const
Retrieve the identifier stored in this nested name specifier.
void resolveKind()
Resolves the result kind of the lookup, possibly hiding decls.
Definition: SemaLookup.cpp:471
Represents the results of name lookup.
Definition: Lookup.h:47
void setAmbiguousBaseSubobjects(CXXBasePaths &P)
Make these results show that the name was found in distinct base classes of the same type...
Definition: SemaLookup.cpp:638
static DeclAccessPair make(NamedDecl *D, AccessSpecifier AS)
virtual bool includeHiddenDecls() const
Determine whether hidden declarations (from unimported modules) should be given to this consumer...
ObjCMethodDecl * getCurMethodDecl()
getCurMethodDecl - If inside of a method body, this returns a pointer to the method decl for the meth...
Definition: Sema.cpp:1201
Namespaces, declared with &#39;namespace foo {}&#39;.
Definition: DeclBase.h:140
static void LookupPotentialTypoResult(Sema &SemaRef, LookupResult &Res, IdentifierInfo *Name, Scope *S, CXXScopeSpec *SS, DeclContext *MemberContext, bool EnteringContext, bool isObjCIvarLookup, bool FindHidden)
Perform name lookup for a possible result for typo correction.
HeaderSearch & getHeaderSearchInfo() const
Definition: Preprocessor.h:821
void setQualifierDistance(unsigned ED)
bool hasTagIdentifierNamespace() const
Definition: DeclBase.h:807
Succeeded, but refers to a deleted function.
Definition: Overload.h:63
bool ValidateCandidate(const TypoCorrection &candidate) override
Simple predicate used by the default RankCandidate to determine whether to return an edit distance of...
Module * getOwningModule(Decl *Entity)
Get the module owning an entity.
Definition: Sema.h:1541
CXXConstructorDecl * DeclareImplicitMoveConstructor(CXXRecordDecl *ClassDecl)
Declare the implicit move constructor for the given class.
ModuleOwnershipKind getModuleOwnershipKind() const
Get the kind of module ownership for this declaration.
Definition: DeclBase.h:784
Look up all declarations in a scope with the given name, including resolved using declarations...
Definition: Sema.h:3017
static NamedDecl * getDefinitionToImport(NamedDecl *D)
Find which declaration we should import to provide the definition of the given declaration.
NamespaceAliasDecl * getAsNamespaceAlias() const
Retrieve the namespace alias stored in this nested name specifier.
const clang::PrintingPolicy & getPrintingPolicy() const
Definition: ASTContext.h:636
IdentifierInfoLookup * getExternalIdentifierLookup() const
Retrieve the external identifier lookup object, if any.
Represents a declaration of a type.
Definition: Decl.h:2816
A set of unresolved declarations.
Definition: UnresolvedSet.h:61
static unsigned getIDNS(Sema::LookupNameKind NameKind, bool CPlusPlus, bool Redeclaration)
Definition: SemaLookup.cpp:209
const Type * getClass() const
Definition: Type.h:2628
Look up the name of an OpenMP user-defined reduction operation.
Definition: Sema.h:3031
std::function< ExprResult(Sema &, TypoExpr *, TypoCorrection)> TypoRecoveryCallback
Definition: Sema.h:3094
Scope - A scope is a transient data structure that is used while parsing the program.
Definition: Scope.h:40
void DiagnoseAmbiguousLookup(LookupResult &Result)
Produce a diagnostic describing the ambiguity that resulted from name lookup.
const Type * getTypePtr() const
Retrieves a pointer to the underlying (unqualified) type.
Definition: Type.h:5825
CXXRecordDecl * getCanonicalDecl() override
Retrieves the "canonical" declaration of the given declaration.
Definition: DeclCXX.h:728
TypoExpr - Internal placeholder for expressions where typo correction still needs to be performed and...
Definition: Expr.h:5312
using_directives_range using_directives()
Definition: Scope.h:464
void append(iterator I, iterator E)
Represents a C++ nested-name-specifier or a global scope specifier.
Definition: DeclSpec.h:63
base_class_iterator bases_begin()
Definition: DeclCXX.h:818
Represents an Objective-C protocol declaration.
Definition: DeclObjC.h:2083
lookups_range lookups() const
Definition: DeclLookups.h:76
DeclContext * getLexicalDeclContext()
getLexicalDeclContext - The declaration context where this Decl was lexically declared (LexicalDC)...
Definition: DeclBase.h:826
LabelDecl * LookupOrCreateLabel(IdentifierInfo *II, SourceLocation IdentLoc, SourceLocation GnuLabelLoc=SourceLocation())
LookupOrCreateLabel - Do a name lookup of a label with the specified name.
const LangOptions & getLangOpts() const
Definition: Sema.h:1193
Labels, declared with &#39;x:&#39; and referenced with &#39;goto x&#39;.
Definition: DeclBase.h:117
const TypoCorrection & getNextCorrection()
Return the next typo correction that passes all internal filters and is deemed valid by the consumer&#39;...
CXXDestructorDecl * getDestructor() const
Returns the destructor decl for this class.
Definition: DeclCXX.cpp:1663
Represents an ObjC class declaration.
Definition: DeclObjC.h:1191
void addDecl(NamedDecl *D)
Add a declaration to these results with its natural access.
Definition: Lookup.h:415
Member name lookup, which finds the names of class/struct/union members.
Definition: Sema.h:3001
NameKind getNameKind() const
getNameKind - Determine what kind of name this is.
Ordinary names.
Definition: DeclBase.h:144
virtual Decl * getCanonicalDecl()
Retrieves the "canonical" declaration of the given declaration.
Definition: DeclBase.h:875
lookup_result lookup(DeclarationName Name) const
lookup - Find the declarations (if any) with the given Name in this context.
Definition: DeclBase.cpp:1539
ExtInfo withCallingConv(CallingConv cc) const
Definition: Type.h:3278
static const unsigned InvalidDistance
CXXSpecialMember
Kinds of C++ special members.
Definition: Sema.h:1129
unsigned getFlags() const
getFlags - Return the flags for this scope.
Definition: Scope.h:217
void LookupVisibleDecls(Scope *S, LookupNameKind Kind, VisibleDeclConsumer &Consumer, bool IncludeGlobalScope=true, bool LoadExternal=true)
Sema - This implements semantic analysis and AST building for C.
Definition: Sema.h:276
udir_range using_directives() const
Returns iterator range [First, Last) of UsingDirectiveDecls stored within this context.
Definition: DeclBase.cpp:1823
NamedDecl * getFoundDecl() const
Get the correction declaration found by name lookup (before we looked through using shadow declaratio...
void setNamingClass(CXXRecordDecl *Record)
Sets the &#39;naming class&#39; for this lookup.
Definition: Lookup.h:397
ArrayRef< Module * > getModulesWithMergedDefinition(const NamedDecl *Def)
Get the additional modules in which the definition Def has been merged.
Definition: ASTContext.h:972
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...
CXXRecordDecl * getAsCXXRecordDecl() const
Retrieves the CXXRecordDecl that this type refers to, either because the type is a RecordType or beca...
Definition: Type.cpp:1590
Represents a prototype with parameter type info, e.g.
Definition: Type.h:3369
std::string CurrentModule
The name of the current module, of which the main source file is a part.
Definition: LangOptions.h:183
This declaration is a C++ operator declared in a non-class context.
Definition: DeclBase.h:168
Objective C @protocol.
Definition: DeclBase.h:147
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:778
bool hasMergedDefinitionInCurrentModule(NamedDecl *Def)
The return type of classify().
Definition: Expr.h:302
DeclarationNameTable DeclarationNames
Definition: ASTContext.h:541
OverloadedOperatorKind getCXXOverloadedOperator() const
getCXXOverloadedOperator - If this name is the name of an overloadable operator in C++ (e...
Provides lookups to, and iteration over, IdentiferInfo objects.
SourceRange getRange() const
Definition: DeclSpec.h:68
void print(raw_ostream &OS, const PrintingPolicy &Policy) const
Print this nested name specifier to the given output stream.
unsigned getEditDistance(bool Normalized=true) const
Gets the "edit distance" of the typo correction from the typo.
std::function< void(const TypoCorrection &)> TypoDiagnosticGenerator
Definition: Sema.h:3092
This declaration is a friend class.
Definition: DeclBase.h:157
std::string getAsString(const LangOptions &LO) const
static bool LookupAnyMember(const CXXBaseSpecifier *Specifier, CXXBasePath &Path, DeclarationName Name)
Callback that looks for any member of a class with the given name.
virtual bool ValidateCandidate(const TypoCorrection &candidate)
Simple predicate used by the default RankCandidate to determine whether to return an edit distance of...
void ArgumentDependentLookup(DeclarationName Name, SourceLocation Loc, ArrayRef< Expr *> Args, ADLResult &Functions)
bool isInlineNamespace() const
Definition: DeclBase.cpp:1019
static bool LookupQualifiedNameInUsingDirectives(Sema &S, LookupResult &R, DeclContext *StartDC)
Perform qualified name lookup in the namespaces nominated by using directives by the given context...
DeclContext * getLexicalParent()
getLexicalParent - Returns the containing lexical DeclContext.
Definition: DeclBase.h:1357
NamespaceDecl * getAsNamespace() const
Retrieve the namespace stored in this nested name specifier.
Expr - This represents one expression.
Definition: Expr.h:106
Defines the clang::LangOptions interface.
LookupNameKind
Describes the kind of name lookup to perform.
Definition: