clang  8.0.0svn
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 
1395 /// Determine whether the module M is part of the current module from the
1396 /// perspective of a module-private visibility check.
1397 static bool isInCurrentModule(const Module *M, const LangOptions &LangOpts) {
1398  // If M is the global module fragment of a module that we've not yet finished
1399  // parsing, then it must be part of the current module.
1400  return M->getTopLevelModuleName() == LangOpts.CurrentModule ||
1401  (M->Kind == Module::GlobalModuleFragment && !M->Parent);
1402 }
1403 
1405  for (const Module *Merged : Context.getModulesWithMergedDefinition(Def))
1406  if (isModuleVisible(Merged))
1407  return true;
1408  return false;
1409 }
1410 
1412  for (const Module *Merged : Context.getModulesWithMergedDefinition(Def))
1413  if (isInCurrentModule(Merged, getLangOpts()))
1414  return true;
1415  return false;
1416 }
1417 
1418 template<typename ParmDecl>
1419 static bool
1420 hasVisibleDefaultArgument(Sema &S, const ParmDecl *D,
1422  if (!D->hasDefaultArgument())
1423  return false;
1424 
1425  while (D) {
1426  auto &DefaultArg = D->getDefaultArgStorage();
1427  if (!DefaultArg.isInherited() && S.isVisible(D))
1428  return true;
1429 
1430  if (!DefaultArg.isInherited() && Modules) {
1431  auto *NonConstD = const_cast<ParmDecl*>(D);
1432  Modules->push_back(S.getOwningModule(NonConstD));
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  }
1470 
1471  // Only return false if there is at least one redecl that is not filtered out.
1472  if (HasFilteredRedecls)
1473  return false;
1474 
1475  return true;
1476 }
1477 
1479  const NamedDecl *D, llvm::SmallVectorImpl<Module *> *Modules) {
1480  return hasVisibleDeclarationImpl(*this, D, Modules, [](const NamedDecl *D) {
1481  if (auto *RD = dyn_cast<CXXRecordDecl>(D))
1482  return RD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization;
1483  if (auto *FD = dyn_cast<FunctionDecl>(D))
1484  return FD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization;
1485  if (auto *VD = dyn_cast<VarDecl>(D))
1486  return VD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization;
1487  llvm_unreachable("unknown explicit specialization kind");
1488  });
1489 }
1490 
1492  const NamedDecl *D, llvm::SmallVectorImpl<Module *> *Modules) {
1493  assert(isa<CXXRecordDecl>(D->getDeclContext()) &&
1494  "not a member specialization");
1495  return hasVisibleDeclarationImpl(*this, D, Modules, [](const NamedDecl *D) {
1496  // If the specialization is declared at namespace scope, then it's a member
1497  // specialization declaration. If it's lexically inside the class
1498  // definition then it was instantiated.
1499  //
1500  // FIXME: This is a hack. There should be a better way to determine this.
1501  // FIXME: What about MS-style explicit specializations declared within a
1502  // class definition?
1503  return D->getLexicalDeclContext()->isFileContext();
1504  });
1505 }
1506 
1507 /// Determine whether a declaration is visible to name lookup.
1508 ///
1509 /// This routine determines whether the declaration D is visible in the current
1510 /// lookup context, taking into account the current template instantiation
1511 /// stack. During template instantiation, a declaration is visible if it is
1512 /// visible from a module containing any entity on the template instantiation
1513 /// path (by instantiating a template, you allow it to see the declarations that
1514 /// your module can see, including those later on in your module).
1515 bool LookupResult::isVisibleSlow(Sema &SemaRef, NamedDecl *D) {
1516  assert(D->isHidden() && "should not call this: not in slow case");
1517 
1518  Module *DeclModule = SemaRef.getOwningModule(D);
1519  assert(DeclModule && "hidden decl has no owning module");
1520 
1521  // If the owning module is visible, the decl is visible.
1522  if (SemaRef.isModuleVisible(DeclModule, D->isModulePrivate()))
1523  return true;
1524 
1525  // Determine whether a decl context is a file context for the purpose of
1526  // visibility. This looks through some (export and linkage spec) transparent
1527  // contexts, but not others (enums).
1528  auto IsEffectivelyFileContext = [](const DeclContext *DC) {
1529  return DC->isFileContext() || isa<LinkageSpecDecl>(DC) ||
1530  isa<ExportDecl>(DC);
1531  };
1532 
1533  // If this declaration is not at namespace scope
1534  // then it is visible if its lexical parent has a visible definition.
1536  if (DC && !IsEffectivelyFileContext(DC)) {
1537  // For a parameter, check whether our current template declaration's
1538  // lexical context is visible, not whether there's some other visible
1539  // definition of it, because parameters aren't "within" the definition.
1540  //
1541  // In C++ we need to check for a visible definition due to ODR merging,
1542  // and in C we must not because each declaration of a function gets its own
1543  // set of declarations for tags in prototype scope.
1544  bool VisibleWithinParent;
1545  if (D->isTemplateParameter() || isa<ParmVarDecl>(D) ||
1546  (isa<FunctionDecl>(DC) && !SemaRef.getLangOpts().CPlusPlus))
1547  VisibleWithinParent = isVisible(SemaRef, cast<NamedDecl>(DC));
1548  else if (D->isModulePrivate()) {
1549  // A module-private declaration is only visible if an enclosing lexical
1550  // parent was merged with another definition in the current module.
1551  VisibleWithinParent = false;
1552  do {
1553  if (SemaRef.hasMergedDefinitionInCurrentModule(cast<NamedDecl>(DC))) {
1554  VisibleWithinParent = true;
1555  break;
1556  }
1557  DC = DC->getLexicalParent();
1558  } while (!IsEffectivelyFileContext(DC));
1559  } else {
1560  VisibleWithinParent = SemaRef.hasVisibleDefinition(cast<NamedDecl>(DC));
1561  }
1562 
1563  if (VisibleWithinParent && SemaRef.CodeSynthesisContexts.empty() &&
1564  // FIXME: Do something better in this case.
1565  !SemaRef.getLangOpts().ModulesLocalVisibility) {
1566  // Cache the fact that this declaration is implicitly visible because
1567  // its parent has a visible definition.
1569  }
1570  return VisibleWithinParent;
1571  }
1572 
1573  return false;
1574 }
1575 
1576 bool Sema::isModuleVisible(const Module *M, bool ModulePrivate) {
1577  // The module might be ordinarily visible. For a module-private query, that
1578  // means it is part of the current module. For any other query, that means it
1579  // is in our visible module set.
1580  if (ModulePrivate) {
1581  if (isInCurrentModule(M, getLangOpts()))
1582  return true;
1583  } else {
1584  if (VisibleModules.isVisible(M))
1585  return true;
1586  }
1587 
1588  // Otherwise, it might be visible by virtue of the query being within a
1589  // template instantiation or similar that is permitted to look inside M.
1590 
1591  // Find the extra places where we need to look.
1592  const auto &LookupModules = getLookupModules();
1593  if (LookupModules.empty())
1594  return false;
1595 
1596  // If our lookup set contains the module, it's visible.
1597  if (LookupModules.count(M))
1598  return true;
1599 
1600  // For a module-private query, that's everywhere we get to look.
1601  if (ModulePrivate)
1602  return false;
1603 
1604  // Check whether M is transitively exported to an import of the lookup set.
1605  return std::any_of(LookupModules.begin(), LookupModules.end(),
1606  [&](const Module *LookupM) {
1607  return LookupM->isModuleVisible(M); });
1608 }
1609 
1610 bool Sema::isVisibleSlow(const NamedDecl *D) {
1611  return LookupResult::isVisible(*this, const_cast<NamedDecl*>(D));
1612 }
1613 
1614 bool Sema::shouldLinkPossiblyHiddenDecl(LookupResult &R, const NamedDecl *New) {
1615  // FIXME: If there are both visible and hidden declarations, we need to take
1616  // into account whether redeclaration is possible. Example:
1617  //
1618  // Non-imported module:
1619  // int f(T); // #1
1620  // Some TU:
1621  // static int f(U); // #2, not a redeclaration of #1
1622  // int f(T); // #3, finds both, should link with #1 if T != U, but
1623  // // with #2 if T == U; neither should be ambiguous.
1624  for (auto *D : R) {
1625  if (isVisible(D))
1626  return true;
1627  assert(D->isExternallyDeclarable() &&
1628  "should not have hidden, non-externally-declarable result here");
1629  }
1630 
1631  // This function is called once "New" is essentially complete, but before a
1632  // previous declaration is attached. We can't query the linkage of "New" in
1633  // general, because attaching the previous declaration can change the
1634  // linkage of New to match the previous declaration.
1635  //
1636  // However, because we've just determined that there is no *visible* prior
1637  // declaration, we can compute the linkage here. There are two possibilities:
1638  //
1639  // * This is not a redeclaration; it's safe to compute the linkage now.
1640  //
1641  // * This is a redeclaration of a prior declaration that is externally
1642  // redeclarable. In that case, the linkage of the declaration is not
1643  // changed by attaching the prior declaration, because both are externally
1644  // declarable (and thus ExternalLinkage or VisibleNoLinkage).
1645  //
1646  // FIXME: This is subtle and fragile.
1647  return New->isExternallyDeclarable();
1648 }
1649 
1650 /// Retrieve the visible declaration corresponding to D, if any.
1651 ///
1652 /// This routine determines whether the declaration D is visible in the current
1653 /// module, with the current imports. If not, it checks whether any
1654 /// redeclaration of D is visible, and if so, returns that declaration.
1655 ///
1656 /// \returns D, or a visible previous declaration of D, whichever is more recent
1657 /// and visible. If no declaration of D is visible, returns null.
1659  unsigned IDNS) {
1660  assert(!LookupResult::isVisible(SemaRef, D) && "not in slow case");
1661 
1662  for (auto RD : D->redecls()) {
1663  // Don't bother with extra checks if we already know this one isn't visible.
1664  if (RD == D)
1665  continue;
1666 
1667  auto ND = cast<NamedDecl>(RD);
1668  // FIXME: This is wrong in the case where the previous declaration is not
1669  // visible in the same scope as D. This needs to be done much more
1670  // carefully.
1671  if (ND->isInIdentifierNamespace(IDNS) &&
1672  LookupResult::isVisible(SemaRef, ND))
1673  return ND;
1674  }
1675 
1676  return nullptr;
1677 }
1678 
1681  assert(!isVisible(D) && "not in slow case");
1682  return hasVisibleDeclarationImpl(*this, D, Modules,
1683  [](const NamedDecl *) { return true; });
1684 }
1685 
1686 NamedDecl *LookupResult::getAcceptableDeclSlow(NamedDecl *D) const {
1687  if (auto *ND = dyn_cast<NamespaceDecl>(D)) {
1688  // Namespaces are a bit of a special case: we expect there to be a lot of
1689  // redeclarations of some namespaces, all declarations of a namespace are
1690  // essentially interchangeable, all declarations are found by name lookup
1691  // if any is, and namespaces are never looked up during template
1692  // instantiation. So we benefit from caching the check in this case, and
1693  // it is correct to do so.
1694  auto *Key = ND->getCanonicalDecl();
1695  if (auto *Acceptable = getSema().VisibleNamespaceCache.lookup(Key))
1696  return Acceptable;
1697  auto *Acceptable = isVisible(getSema(), Key)
1698  ? Key
1699  : findAcceptableDecl(getSema(), Key, IDNS);
1700  if (Acceptable)
1701  getSema().VisibleNamespaceCache.insert(std::make_pair(Key, Acceptable));
1702  return Acceptable;
1703  }
1704 
1705  return findAcceptableDecl(getSema(), D, IDNS);
1706 }
1707 
1708 /// Perform unqualified name lookup starting from a given
1709 /// scope.
1710 ///
1711 /// Unqualified name lookup (C++ [basic.lookup.unqual], C99 6.2.1) is
1712 /// used to find names within the current scope. For example, 'x' in
1713 /// @code
1714 /// int x;
1715 /// int f() {
1716 /// return x; // unqualified name look finds 'x' in the global scope
1717 /// }
1718 /// @endcode
1719 ///
1720 /// Different lookup criteria can find different names. For example, a
1721 /// particular scope can have both a struct and a function of the same
1722 /// name, and each can be found by certain lookup criteria. For more
1723 /// information about lookup criteria, see the documentation for the
1724 /// class LookupCriteria.
1725 ///
1726 /// @param S The scope from which unqualified name lookup will
1727 /// begin. If the lookup criteria permits, name lookup may also search
1728 /// in the parent scopes.
1729 ///
1730 /// @param [in,out] R Specifies the lookup to perform (e.g., the name to
1731 /// look up and the lookup kind), and is updated with the results of lookup
1732 /// including zero or more declarations and possibly additional information
1733 /// used to diagnose ambiguities.
1734 ///
1735 /// @returns \c true if lookup succeeded and false otherwise.
1736 bool Sema::LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation) {
1737  DeclarationName Name = R.getLookupName();
1738  if (!Name) return false;
1739 
1740  LookupNameKind NameKind = R.getLookupKind();
1741 
1742  if (!getLangOpts().CPlusPlus) {
1743  // Unqualified name lookup in C/Objective-C is purely lexical, so
1744  // search in the declarations attached to the name.
1745  if (NameKind == Sema::LookupRedeclarationWithLinkage) {
1746  // Find the nearest non-transparent declaration scope.
1747  while (!(S->getFlags() & Scope::DeclScope) ||
1748  (S->getEntity() && S->getEntity()->isTransparentContext()))
1749  S = S->getParent();
1750  }
1751 
1752  // When performing a scope lookup, we want to find local extern decls.
1753  FindLocalExternScope FindLocals(R);
1754 
1755  // Scan up the scope chain looking for a decl that matches this
1756  // identifier that is in the appropriate namespace. This search
1757  // should not take long, as shadowing of names is uncommon, and
1758  // deep shadowing is extremely uncommon.
1759  bool LeftStartingScope = false;
1760 
1761  for (IdentifierResolver::iterator I = IdResolver.begin(Name),
1762  IEnd = IdResolver.end();
1763  I != IEnd; ++I)
1764  if (NamedDecl *D = R.getAcceptableDecl(*I)) {
1765  if (NameKind == LookupRedeclarationWithLinkage) {
1766  // Determine whether this (or a previous) declaration is
1767  // out-of-scope.
1768  if (!LeftStartingScope && !S->isDeclScope(*I))
1769  LeftStartingScope = true;
1770 
1771  // If we found something outside of our starting scope that
1772  // does not have linkage, skip it.
1773  if (LeftStartingScope && !((*I)->hasLinkage())) {
1774  R.setShadowed();
1775  continue;
1776  }
1777  }
1778  else if (NameKind == LookupObjCImplicitSelfParam &&
1779  !isa<ImplicitParamDecl>(*I))
1780  continue;
1781 
1782  R.addDecl(D);
1783 
1784  // Check whether there are any other declarations with the same name
1785  // and in the same scope.
1786  if (I != IEnd) {
1787  // Find the scope in which this declaration was declared (if it
1788  // actually exists in a Scope).
1789  while (S && !S->isDeclScope(D))
1790  S = S->getParent();
1791 
1792  // If the scope containing the declaration is the translation unit,
1793  // then we'll need to perform our checks based on the matching
1794  // DeclContexts rather than matching scopes.
1796  S = nullptr;
1797 
1798  // Compute the DeclContext, if we need it.
1799  DeclContext *DC = nullptr;
1800  if (!S)
1801  DC = (*I)->getDeclContext()->getRedeclContext();
1802 
1803  IdentifierResolver::iterator LastI = I;
1804  for (++LastI; LastI != IEnd; ++LastI) {
1805  if (S) {
1806  // Match based on scope.
1807  if (!S->isDeclScope(*LastI))
1808  break;
1809  } else {
1810  // Match based on DeclContext.
1811  DeclContext *LastDC
1812  = (*LastI)->getDeclContext()->getRedeclContext();
1813  if (!LastDC->Equals(DC))
1814  break;
1815  }
1816 
1817  // If the declaration is in the right namespace and visible, add it.
1818  if (NamedDecl *LastD = R.getAcceptableDecl(*LastI))
1819  R.addDecl(LastD);
1820  }
1821 
1822  R.resolveKind();
1823  }
1824 
1825  return true;
1826  }
1827  } else {
1828  // Perform C++ unqualified name lookup.
1829  if (CppLookupName(R, S))
1830  return true;
1831  }
1832 
1833  // If we didn't find a use of this identifier, and if the identifier
1834  // corresponds to a compiler builtin, create the decl object for the builtin
1835  // now, injecting it into translation unit scope, and return it.
1836  if (AllowBuiltinCreation && LookupBuiltin(*this, R))
1837  return true;
1838 
1839  // If we didn't find a use of this identifier, the ExternalSource
1840  // may be able to handle the situation.
1841  // Note: some lookup failures are expected!
1842  // See e.g. R.isForRedeclaration().
1843  return (ExternalSource && ExternalSource->LookupUnqualified(R, S));
1844 }
1845 
1846 /// Perform qualified name lookup in the namespaces nominated by
1847 /// using directives by the given context.
1848 ///
1849 /// C++98 [namespace.qual]p2:
1850 /// Given X::m (where X is a user-declared namespace), or given \::m
1851 /// (where X is the global namespace), let S be the set of all
1852 /// declarations of m in X and in the transitive closure of all
1853 /// namespaces nominated by using-directives in X and its used
1854 /// namespaces, except that using-directives are ignored in any
1855 /// namespace, including X, directly containing one or more
1856 /// declarations of m. No namespace is searched more than once in
1857 /// the lookup of a name. If S is the empty set, the program is
1858 /// ill-formed. Otherwise, if S has exactly one member, or if the
1859 /// context of the reference is a using-declaration
1860 /// (namespace.udecl), S is the required set of declarations of
1861 /// m. Otherwise if the use of m is not one that allows a unique
1862 /// declaration to be chosen from S, the program is ill-formed.
1863 ///
1864 /// C++98 [namespace.qual]p5:
1865 /// During the lookup of a qualified namespace member name, if the
1866 /// lookup finds more than one declaration of the member, and if one
1867 /// declaration introduces a class name or enumeration name and the
1868 /// other declarations either introduce the same object, the same
1869 /// enumerator or a set of functions, the non-type name hides the
1870 /// class or enumeration name if and only if the declarations are
1871 /// from the same namespace; otherwise (the declarations are from
1872 /// different namespaces), the program is ill-formed.
1874  DeclContext *StartDC) {
1875  assert(StartDC->isFileContext() && "start context is not a file context");
1876 
1877  // We have not yet looked into these namespaces, much less added
1878  // their "using-children" to the queue.
1880 
1881  // We have at least added all these contexts to the queue.
1882  llvm::SmallPtrSet<DeclContext*, 8> Visited;
1883  Visited.insert(StartDC);
1884 
1885  // We have already looked into the initial namespace; seed the queue
1886  // with its using-children.
1887  for (auto *I : StartDC->using_directives()) {
1888  NamespaceDecl *ND = I->getNominatedNamespace()->getOriginalNamespace();
1889  if (S.isVisible(I) && Visited.insert(ND).second)
1890  Queue.push_back(ND);
1891  }
1892 
1893  // The easiest way to implement the restriction in [namespace.qual]p5
1894  // is to check whether any of the individual results found a tag
1895  // and, if so, to declare an ambiguity if the final result is not
1896  // a tag.
1897  bool FoundTag = false;
1898  bool FoundNonTag = false;
1899 
1901 
1902  bool Found = false;
1903  while (!Queue.empty()) {
1904  NamespaceDecl *ND = Queue.pop_back_val();
1905 
1906  // We go through some convolutions here to avoid copying results
1907  // between LookupResults.
1908  bool UseLocal = !R.empty();
1909  LookupResult &DirectR = UseLocal ? LocalR : R;
1910  bool FoundDirect = LookupDirect(S, DirectR, ND);
1911 
1912  if (FoundDirect) {
1913  // First do any local hiding.
1914  DirectR.resolveKind();
1915 
1916  // If the local result is a tag, remember that.
1917  if (DirectR.isSingleTagDecl())
1918  FoundTag = true;
1919  else
1920  FoundNonTag = true;
1921 
1922  // Append the local results to the total results if necessary.
1923  if (UseLocal) {
1924  R.addAllDecls(LocalR);
1925  LocalR.clear();
1926  }
1927  }
1928 
1929  // If we find names in this namespace, ignore its using directives.
1930  if (FoundDirect) {
1931  Found = true;
1932  continue;
1933  }
1934 
1935  for (auto I : ND->using_directives()) {
1936  NamespaceDecl *Nom = I->getNominatedNamespace();
1937  if (S.isVisible(I) && Visited.insert(Nom).second)
1938  Queue.push_back(Nom);
1939  }
1940  }
1941 
1942  if (Found) {
1943  if (FoundTag && FoundNonTag)
1945  else
1946  R.resolveKind();
1947  }
1948 
1949  return Found;
1950 }
1951 
1952 /// Callback that looks for any member of a class with the given name.
1954  CXXBasePath &Path, DeclarationName Name) {
1955  RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl();
1956 
1957  Path.Decls = BaseRecord->lookup(Name);
1958  return !Path.Decls.empty();
1959 }
1960 
1961 /// Determine whether the given set of member declarations contains only
1962 /// static members, nested types, and enumerators.
1963 template<typename InputIterator>
1964 static bool HasOnlyStaticMembers(InputIterator First, InputIterator Last) {
1965  Decl *D = (*First)->getUnderlyingDecl();
1966  if (isa<VarDecl>(D) || isa<TypeDecl>(D) || isa<EnumConstantDecl>(D))
1967  return true;
1968 
1969  if (isa<CXXMethodDecl>(D)) {
1970  // Determine whether all of the methods are static.
1971  bool AllMethodsAreStatic = true;
1972  for(; First != Last; ++First) {
1973  D = (*First)->getUnderlyingDecl();
1974 
1975  if (!isa<CXXMethodDecl>(D)) {
1976  assert(isa<TagDecl>(D) && "Non-function must be a tag decl");
1977  break;
1978  }
1979 
1980  if (!cast<CXXMethodDecl>(D)->isStatic()) {
1981  AllMethodsAreStatic = false;
1982  break;
1983  }
1984  }
1985 
1986  if (AllMethodsAreStatic)
1987  return true;
1988  }
1989 
1990  return false;
1991 }
1992 
1993 /// Perform qualified name lookup into a given context.
1994 ///
1995 /// Qualified name lookup (C++ [basic.lookup.qual]) is used to find
1996 /// names when the context of those names is explicit specified, e.g.,
1997 /// "std::vector" or "x->member", or as part of unqualified name lookup.
1998 ///
1999 /// Different lookup criteria can find different names. For example, a
2000 /// particular scope can have both a struct and a function of the same
2001 /// name, and each can be found by certain lookup criteria. For more
2002 /// information about lookup criteria, see the documentation for the
2003 /// class LookupCriteria.
2004 ///
2005 /// \param R captures both the lookup criteria and any lookup results found.
2006 ///
2007 /// \param LookupCtx The context in which qualified name lookup will
2008 /// search. If the lookup criteria permits, name lookup may also search
2009 /// in the parent contexts or (for C++ classes) base classes.
2010 ///
2011 /// \param InUnqualifiedLookup true if this is qualified name lookup that
2012 /// occurs as part of unqualified name lookup.
2013 ///
2014 /// \returns true if lookup succeeded, false if it failed.
2016  bool InUnqualifiedLookup) {
2017  assert(LookupCtx && "Sema::LookupQualifiedName requires a lookup context");
2018 
2019  if (!R.getLookupName())
2020  return false;
2021 
2022  // Make sure that the declaration context is complete.
2023  assert((!isa<TagDecl>(LookupCtx) ||
2024  LookupCtx->isDependentContext() ||
2025  cast<TagDecl>(LookupCtx)->isCompleteDefinition() ||
2026  cast<TagDecl>(LookupCtx)->isBeingDefined()) &&
2027  "Declaration context must already be complete!");
2028 
2029  struct QualifiedLookupInScope {
2030  bool oldVal;
2031  DeclContext *Context;
2032  // Set flag in DeclContext informing debugger that we're looking for qualified name
2033  QualifiedLookupInScope(DeclContext *ctx) : Context(ctx) {
2034  oldVal = ctx->setUseQualifiedLookup();
2035  }
2036  ~QualifiedLookupInScope() {
2037  Context->setUseQualifiedLookup(oldVal);
2038  }
2039  } QL(LookupCtx);
2040 
2041  if (LookupDirect(*this, R, LookupCtx)) {
2042  R.resolveKind();
2043  if (isa<CXXRecordDecl>(LookupCtx))
2044  R.setNamingClass(cast<CXXRecordDecl>(LookupCtx));
2045  return true;
2046  }
2047 
2048  // Don't descend into implied contexts for redeclarations.
2049  // C++98 [namespace.qual]p6:
2050  // In a declaration for a namespace member in which the
2051  // declarator-id is a qualified-id, given that the qualified-id
2052  // for the namespace member has the form
2053  // nested-name-specifier unqualified-id
2054  // the unqualified-id shall name a member of the namespace
2055  // designated by the nested-name-specifier.
2056  // See also [class.mfct]p5 and [class.static.data]p2.
2057  if (R.isForRedeclaration())
2058  return false;
2059 
2060  // If this is a namespace, look it up in the implied namespaces.
2061  if (LookupCtx->isFileContext())
2062  return LookupQualifiedNameInUsingDirectives(*this, R, LookupCtx);
2063 
2064  // If this isn't a C++ class, we aren't allowed to look into base
2065  // classes, we're done.
2066  CXXRecordDecl *LookupRec = dyn_cast<CXXRecordDecl>(LookupCtx);
2067  if (!LookupRec || !LookupRec->getDefinition())
2068  return false;
2069 
2070  // If we're performing qualified name lookup into a dependent class,
2071  // then we are actually looking into a current instantiation. If we have any
2072  // dependent base classes, then we either have to delay lookup until
2073  // template instantiation time (at which point all bases will be available)
2074  // or we have to fail.
2075  if (!InUnqualifiedLookup && LookupRec->isDependentContext() &&
2076  LookupRec->hasAnyDependentBases()) {
2078  return false;
2079  }
2080 
2081  // Perform lookup into our base classes.
2082  CXXBasePaths Paths;
2083  Paths.setOrigin(LookupRec);
2084 
2085  // Look for this member in our base classes
2086  bool (*BaseCallback)(const CXXBaseSpecifier *Specifier, CXXBasePath &Path,
2087  DeclarationName Name) = nullptr;
2088  switch (R.getLookupKind()) {
2089  case LookupObjCImplicitSelfParam:
2090  case LookupOrdinaryName:
2091  case LookupMemberName:
2092  case LookupRedeclarationWithLinkage:
2093  case LookupLocalFriendName:
2094  BaseCallback = &CXXRecordDecl::FindOrdinaryMember;
2095  break;
2096 
2097  case LookupTagName:
2098  BaseCallback = &CXXRecordDecl::FindTagMember;
2099  break;
2100 
2101  case LookupAnyName:
2102  BaseCallback = &LookupAnyMember;
2103  break;
2104 
2105  case LookupOMPReductionName:
2106  BaseCallback = &CXXRecordDecl::FindOMPReductionMember;
2107  break;
2108 
2109  case LookupUsingDeclName:
2110  // This lookup is for redeclarations only.
2111 
2112  case LookupOperatorName:
2113  case LookupNamespaceName:
2114  case LookupObjCProtocolName:
2115  case LookupLabel:
2116  // These lookups will never find a member in a C++ class (or base class).
2117  return false;
2118 
2119  case LookupNestedNameSpecifierName:
2121  break;
2122  }
2123 
2124  DeclarationName Name = R.getLookupName();
2125  if (!LookupRec->lookupInBases(
2126  [=](const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
2127  return BaseCallback(Specifier, Path, Name);
2128  },
2129  Paths))
2130  return false;
2131 
2132  R.setNamingClass(LookupRec);
2133 
2134  // C++ [class.member.lookup]p2:
2135  // [...] If the resulting set of declarations are not all from
2136  // sub-objects of the same type, or the set has a nonstatic member
2137  // and includes members from distinct sub-objects, there is an
2138  // ambiguity and the program is ill-formed. Otherwise that set is
2139  // the result of the lookup.
2140  QualType SubobjectType;
2141  int SubobjectNumber = 0;
2142  AccessSpecifier SubobjectAccess = AS_none;
2143 
2144  for (CXXBasePaths::paths_iterator Path = Paths.begin(), PathEnd = Paths.end();
2145  Path != PathEnd; ++Path) {
2146  const CXXBasePathElement &PathElement = Path->back();
2147 
2148  // Pick the best (i.e. most permissive i.e. numerically lowest) access
2149  // across all paths.
2150  SubobjectAccess = std::min(SubobjectAccess, Path->Access);
2151 
2152  // Determine whether we're looking at a distinct sub-object or not.
2153  if (SubobjectType.isNull()) {
2154  // This is the first subobject we've looked at. Record its type.
2155  SubobjectType = Context.getCanonicalType(PathElement.Base->getType());
2156  SubobjectNumber = PathElement.SubobjectNumber;
2157  continue;
2158  }
2159 
2160  if (SubobjectType
2161  != Context.getCanonicalType(PathElement.Base->getType())) {
2162  // We found members of the given name in two subobjects of
2163  // different types. If the declaration sets aren't the same, this
2164  // lookup is ambiguous.
2165  if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end())) {
2166  CXXBasePaths::paths_iterator FirstPath = Paths.begin();
2167  DeclContext::lookup_iterator FirstD = FirstPath->Decls.begin();
2168  DeclContext::lookup_iterator CurrentD = Path->Decls.begin();
2169 
2170  while (FirstD != FirstPath->Decls.end() &&
2171  CurrentD != Path->Decls.end()) {
2172  if ((*FirstD)->getUnderlyingDecl()->getCanonicalDecl() !=
2173  (*CurrentD)->getUnderlyingDecl()->getCanonicalDecl())
2174  break;
2175 
2176  ++FirstD;
2177  ++CurrentD;
2178  }
2179 
2180  if (FirstD == FirstPath->Decls.end() &&
2181  CurrentD == Path->Decls.end())
2182  continue;
2183  }
2184 
2186  return true;
2187  }
2188 
2189  if (SubobjectNumber != PathElement.SubobjectNumber) {
2190  // We have a different subobject of the same type.
2191 
2192  // C++ [class.member.lookup]p5:
2193  // A static member, a nested type or an enumerator defined in
2194  // a base class T can unambiguously be found even if an object
2195  // has more than one base class subobject of type T.
2196  if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end()))
2197  continue;
2198 
2199  // We have found a nonstatic member name in multiple, distinct
2200  // subobjects. Name lookup is ambiguous.
2201  R.setAmbiguousBaseSubobjects(Paths);
2202  return true;
2203  }
2204  }
2205 
2206  // Lookup in a base class succeeded; return these results.
2207 
2208  for (auto *D : Paths.front().Decls) {
2209  AccessSpecifier AS = CXXRecordDecl::MergeAccess(SubobjectAccess,
2210  D->getAccess());
2211  R.addDecl(D, AS);
2212  }
2213  R.resolveKind();
2214  return true;
2215 }
2216 
2217 /// Performs qualified name lookup or special type of lookup for
2218 /// "__super::" scope specifier.
2219 ///
2220 /// This routine is a convenience overload meant to be called from contexts
2221 /// that need to perform a qualified name lookup with an optional C++ scope
2222 /// specifier that might require special kind of lookup.
2223 ///
2224 /// \param R captures both the lookup criteria and any lookup results found.
2225 ///
2226 /// \param LookupCtx The context in which qualified name lookup will
2227 /// search.
2228 ///
2229 /// \param SS An optional C++ scope-specifier.
2230 ///
2231 /// \returns true if lookup succeeded, false if it failed.
2233  CXXScopeSpec &SS) {
2234  auto *NNS = SS.getScopeRep();
2235  if (NNS && NNS->getKind() == NestedNameSpecifier::Super)
2236  return LookupInSuper(R, NNS->getAsRecordDecl());
2237  else
2238 
2239  return LookupQualifiedName(R, LookupCtx);
2240 }
2241 
2242 /// Performs name lookup for a name that was parsed in the
2243 /// source code, and may contain a C++ scope specifier.
2244 ///
2245 /// This routine is a convenience routine meant to be called from
2246 /// contexts that receive a name and an optional C++ scope specifier
2247 /// (e.g., "N::M::x"). It will then perform either qualified or
2248 /// unqualified name lookup (with LookupQualifiedName or LookupName,
2249 /// respectively) on the given name and return those results. It will
2250 /// perform a special type of lookup for "__super::" scope specifier.
2251 ///
2252 /// @param S The scope from which unqualified name lookup will
2253 /// begin.
2254 ///
2255 /// @param SS An optional C++ scope-specifier, e.g., "::N::M".
2256 ///
2257 /// @param EnteringContext Indicates whether we are going to enter the
2258 /// context of the scope-specifier SS (if present).
2259 ///
2260 /// @returns True if any decls were found (but possibly ambiguous)
2262  bool AllowBuiltinCreation, bool EnteringContext) {
2263  if (SS && SS->isInvalid()) {
2264  // When the scope specifier is invalid, don't even look for
2265  // anything.
2266  return false;
2267  }
2268 
2269  if (SS && SS->isSet()) {
2270  NestedNameSpecifier *NNS = SS->getScopeRep();
2271  if (NNS->getKind() == NestedNameSpecifier::Super)
2272  return LookupInSuper(R, NNS->getAsRecordDecl());
2273 
2274  if (DeclContext *DC = computeDeclContext(*SS, EnteringContext)) {
2275  // We have resolved the scope specifier to a particular declaration
2276  // contex, and will perform name lookup in that context.
2277  if (!DC->isDependentContext() && RequireCompleteDeclContext(*SS, DC))
2278  return false;
2279 
2280  R.setContextRange(SS->getRange());
2281  return LookupQualifiedName(R, DC);
2282  }
2283 
2284  // We could not resolve the scope specified to a specific declaration
2285  // context, which means that SS refers to an unknown specialization.
2286  // Name lookup can't find anything in this case.
2288  R.setContextRange(SS->getRange());
2289  return false;
2290  }
2291 
2292  // Perform unqualified name lookup starting in the given scope.
2293  return LookupName(R, S, AllowBuiltinCreation);
2294 }
2295 
2296 /// Perform qualified name lookup into all base classes of the given
2297 /// class.
2298 ///
2299 /// \param R captures both the lookup criteria and any lookup results found.
2300 ///
2301 /// \param Class The context in which qualified name lookup will
2302 /// search. Name lookup will search in all base classes merging the results.
2303 ///
2304 /// @returns True if any decls were found (but possibly ambiguous)
2306  // The access-control rules we use here are essentially the rules for
2307  // doing a lookup in Class that just magically skipped the direct
2308  // members of Class itself. That is, the naming class is Class, and the
2309  // access includes the access of the base.
2310  for (const auto &BaseSpec : Class->bases()) {
2311  CXXRecordDecl *RD = cast<CXXRecordDecl>(
2312  BaseSpec.getType()->castAs<RecordType>()->getDecl());
2313  LookupResult Result(*this, R.getLookupNameInfo(), R.getLookupKind());
2314  Result.setBaseObjectType(Context.getRecordType(Class));
2315  LookupQualifiedName(Result, RD);
2316 
2317  // Copy the lookup results into the target, merging the base's access into
2318  // the path access.
2319  for (auto I = Result.begin(), E = Result.end(); I != E; ++I) {
2320  R.addDecl(I.getDecl(),
2321  CXXRecordDecl::MergeAccess(BaseSpec.getAccessSpecifier(),
2322  I.getAccess()));
2323  }
2324 
2325  Result.suppressDiagnostics();
2326  }
2327 
2328  R.resolveKind();
2329  R.setNamingClass(Class);
2330 
2331  return !R.empty();
2332 }
2333 
2334 /// Produce a diagnostic describing the ambiguity that resulted
2335 /// from name lookup.
2336 ///
2337 /// \param Result The result of the ambiguous lookup to be diagnosed.
2339  assert(Result.isAmbiguous() && "Lookup result must be ambiguous");
2340 
2341  DeclarationName Name = Result.getLookupName();
2342  SourceLocation NameLoc = Result.getNameLoc();
2343  SourceRange LookupRange = Result.getContextRange();
2344 
2345  switch (Result.getAmbiguityKind()) {
2347  CXXBasePaths *Paths = Result.getBasePaths();
2348  QualType SubobjectType = Paths->front().back().Base->getType();
2349  Diag(NameLoc, diag::err_ambiguous_member_multiple_subobjects)
2350  << Name << SubobjectType << getAmbiguousPathsDisplayString(*Paths)
2351  << LookupRange;
2352 
2353  DeclContext::lookup_iterator Found = Paths->front().Decls.begin();
2354  while (isa<CXXMethodDecl>(*Found) &&
2355  cast<CXXMethodDecl>(*Found)->isStatic())
2356  ++Found;
2357 
2358  Diag((*Found)->getLocation(), diag::note_ambiguous_member_found);
2359  break;
2360  }
2361 
2363  Diag(NameLoc, diag::err_ambiguous_member_multiple_subobject_types)
2364  << Name << LookupRange;
2365 
2366  CXXBasePaths *Paths = Result.getBasePaths();
2367  std::set<Decl *> DeclsPrinted;
2368  for (CXXBasePaths::paths_iterator Path = Paths->begin(),
2369  PathEnd = Paths->end();
2370  Path != PathEnd; ++Path) {
2371  Decl *D = Path->Decls.front();
2372  if (DeclsPrinted.insert(D).second)
2373  Diag(D->getLocation(), diag::note_ambiguous_member_found);
2374  }
2375  break;
2376  }
2377 
2379  Diag(NameLoc, diag::err_ambiguous_tag_hiding) << Name << LookupRange;
2380 
2381  llvm::SmallPtrSet<NamedDecl*, 8> TagDecls;
2382 
2383  for (auto *D : Result)
2384  if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
2385  TagDecls.insert(TD);
2386  Diag(TD->getLocation(), diag::note_hidden_tag);
2387  }
2388 
2389  for (auto *D : Result)
2390  if (!isa<TagDecl>(D))
2391  Diag(D->getLocation(), diag::note_hiding_object);
2392 
2393  // For recovery purposes, go ahead and implement the hiding.
2394  LookupResult::Filter F = Result.makeFilter();
2395  while (F.hasNext()) {
2396  if (TagDecls.count(F.next()))
2397  F.erase();
2398  }
2399  F.done();
2400  break;
2401  }
2402 
2404  Diag(NameLoc, diag::err_ambiguous_reference) << Name << LookupRange;
2405 
2406  for (auto *D : Result)
2407  Diag(D->getLocation(), diag::note_ambiguous_candidate) << D;
2408  break;
2409  }
2410  }
2411 }
2412 
2413 namespace {
2414  struct AssociatedLookup {
2415  AssociatedLookup(Sema &S, SourceLocation InstantiationLoc,
2416  Sema::AssociatedNamespaceSet &Namespaces,
2417  Sema::AssociatedClassSet &Classes)
2418  : S(S), Namespaces(Namespaces), Classes(Classes),
2419  InstantiationLoc(InstantiationLoc) {
2420  }
2421 
2422  Sema &S;
2423  Sema::AssociatedNamespaceSet &Namespaces;
2424  Sema::AssociatedClassSet &Classes;
2425  SourceLocation InstantiationLoc;
2426  };
2427 } // end anonymous namespace
2428 
2429 static void
2430 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType T);
2431 
2433  DeclContext *Ctx) {
2434  // Add the associated namespace for this class.
2435 
2436  // We don't use DeclContext::getEnclosingNamespaceContext() as this may
2437  // be a locally scoped record.
2438 
2439  // We skip out of inline namespaces. The innermost non-inline namespace
2440  // contains all names of all its nested inline namespaces anyway, so we can
2441  // replace the entire inline namespace tree with its root.
2442  while (Ctx->isRecord() || Ctx->isTransparentContext() ||
2443  Ctx->isInlineNamespace())
2444  Ctx = Ctx->getParent();
2445 
2446  if (Ctx->isFileContext())
2447  Namespaces.insert(Ctx->getPrimaryContext());
2448 }
2449 
2450 // Add the associated classes and namespaces for argument-dependent
2451 // lookup that involves a template argument (C++ [basic.lookup.koenig]p2).
2452 static void
2453 addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
2454  const TemplateArgument &Arg) {
2455  // C++ [basic.lookup.koenig]p2, last bullet:
2456  // -- [...] ;
2457  switch (Arg.getKind()) {
2459  break;
2460 
2462  // [...] the namespaces and classes associated with the types of the
2463  // template arguments provided for template type parameters (excluding
2464  // template template parameters)
2466  break;
2467 
2470  // [...] the namespaces in which any template template arguments are
2471  // defined; and the classes in which any member templates used as
2472  // template template arguments are defined.
2474  if (ClassTemplateDecl *ClassTemplate
2475  = dyn_cast<ClassTemplateDecl>(Template.getAsTemplateDecl())) {
2476  DeclContext *Ctx = ClassTemplate->getDeclContext();
2477  if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2478  Result.Classes.insert(EnclosingClass);
2479  // Add the associated namespace for this class.
2480  CollectEnclosingNamespace(Result.Namespaces, Ctx);
2481  }
2482  break;
2483  }
2484 
2489  // [Note: non-type template arguments do not contribute to the set of
2490  // associated namespaces. ]
2491  break;
2492 
2494  for (const auto &P : Arg.pack_elements())
2496  break;
2497  }
2498 }
2499 
2500 // Add the associated classes and namespaces for
2501 // argument-dependent lookup with an argument of class type
2502 // (C++ [basic.lookup.koenig]p2).
2503 static void
2504 addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
2505  CXXRecordDecl *Class) {
2506 
2507  // Just silently ignore anything whose name is __va_list_tag.
2508  if (Class->getDeclName() == Result.S.VAListTagName)
2509  return;
2510 
2511  // C++ [basic.lookup.koenig]p2:
2512  // [...]
2513  // -- If T is a class type (including unions), its associated
2514  // classes are: the class itself; the class of which it is a
2515  // member, if any; and its direct and indirect base
2516  // classes. Its associated namespaces are the namespaces in
2517  // which its associated classes are defined.
2518 
2519  // Add the class of which it is a member, if any.
2520  DeclContext *Ctx = Class->getDeclContext();
2521  if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2522  Result.Classes.insert(EnclosingClass);
2523  // Add the associated namespace for this class.
2524  CollectEnclosingNamespace(Result.Namespaces, Ctx);
2525 
2526  // Add the class itself. If we've already seen this class, we don't
2527  // need to visit base classes.
2528  //
2529  // FIXME: That's not correct, we may have added this class only because it
2530  // was the enclosing class of another class, and in that case we won't have
2531  // added its base classes yet.
2532  if (!Result.Classes.insert(Class))
2533  return;
2534 
2535  // -- If T is a template-id, its associated namespaces and classes are
2536  // the namespace in which the template is defined; for member
2537  // templates, the member template's class; the namespaces and classes
2538  // associated with the types of the template arguments provided for
2539  // template type parameters (excluding template template parameters); the
2540  // namespaces in which any template template arguments are defined; and
2541  // the classes in which any member templates used as template template
2542  // arguments are defined. [Note: non-type template arguments do not
2543  // contribute to the set of associated namespaces. ]
2545  = dyn_cast<ClassTemplateSpecializationDecl>(Class)) {
2546  DeclContext *Ctx = Spec->getSpecializedTemplate()->getDeclContext();
2547  if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2548  Result.Classes.insert(EnclosingClass);
2549  // Add the associated namespace for this class.
2550  CollectEnclosingNamespace(Result.Namespaces, Ctx);
2551 
2552  const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
2553  for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
2554  addAssociatedClassesAndNamespaces(Result, TemplateArgs[I]);
2555  }
2556 
2557  // Only recurse into base classes for complete types.
2558  if (!Result.S.isCompleteType(Result.InstantiationLoc,
2559  Result.S.Context.getRecordType(Class)))
2560  return;
2561 
2562  // Add direct and indirect base classes along with their associated
2563  // namespaces.
2565  Bases.push_back(Class);
2566  while (!Bases.empty()) {
2567  // Pop this class off the stack.
2568  Class = Bases.pop_back_val();
2569 
2570  // Visit the base classes.
2571  for (const auto &Base : Class->bases()) {
2572  const RecordType *BaseType = Base.getType()->getAs<RecordType>();
2573  // In dependent contexts, we do ADL twice, and the first time around,
2574  // the base type might be a dependent TemplateSpecializationType, or a
2575  // TemplateTypeParmType. If that happens, simply ignore it.
2576  // FIXME: If we want to support export, we probably need to add the
2577  // namespace of the template in a TemplateSpecializationType, or even
2578  // the classes and namespaces of known non-dependent arguments.
2579  if (!BaseType)
2580  continue;
2581  CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(BaseType->getDecl());
2582  if (Result.Classes.insert(BaseDecl)) {
2583  // Find the associated namespace for this base class.
2584  DeclContext *BaseCtx = BaseDecl->getDeclContext();
2585  CollectEnclosingNamespace(Result.Namespaces, BaseCtx);
2586 
2587  // Make sure we visit the bases of this base class.
2588  if (BaseDecl->bases_begin() != BaseDecl->bases_end())
2589  Bases.push_back(BaseDecl);
2590  }
2591  }
2592  }
2593 }
2594 
2595 // Add the associated classes and namespaces for
2596 // argument-dependent lookup with an argument of type T
2597 // (C++ [basic.lookup.koenig]p2).
2598 static void
2599 addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType Ty) {
2600  // C++ [basic.lookup.koenig]p2:
2601  //
2602  // For each argument type T in the function call, there is a set
2603  // of zero or more associated namespaces and a set of zero or more
2604  // associated classes to be considered. The sets of namespaces and
2605  // classes is determined entirely by the types of the function
2606  // arguments (and the namespace of any template template
2607  // argument). Typedef names and using-declarations used to specify
2608  // the types do not contribute to this set. The sets of namespaces
2609  // and classes are determined in the following way:
2610 
2612  const Type *T = Ty->getCanonicalTypeInternal().getTypePtr();
2613 
2614  while (true) {
2615  switch (T->getTypeClass()) {
2616 
2617 #define TYPE(Class, Base)
2618 #define DEPENDENT_TYPE(Class, Base) case Type::Class:
2619 #define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2620 #define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
2621 #define ABSTRACT_TYPE(Class, Base)
2622 #include "clang/AST/TypeNodes.def"
2623  // T is canonical. We can also ignore dependent types because
2624  // we don't need to do ADL at the definition point, but if we
2625  // wanted to implement template export (or if we find some other
2626  // use for associated classes and namespaces...) this would be
2627  // wrong.
2628  break;
2629 
2630  // -- If T is a pointer to U or an array of U, its associated
2631  // namespaces and classes are those associated with U.
2632  case Type::Pointer:
2633  T = cast<PointerType>(T)->getPointeeType().getTypePtr();
2634  continue;
2635  case Type::ConstantArray:
2636  case Type::IncompleteArray:
2637  case Type::VariableArray:
2638  T = cast<ArrayType>(T)->getElementType().getTypePtr();
2639  continue;
2640 
2641  // -- If T is a fundamental type, its associated sets of
2642  // namespaces and classes are both empty.
2643  case Type::Builtin:
2644  break;
2645 
2646  // -- If T is a class type (including unions), its associated
2647  // classes are: the class itself; the class of which it is a
2648  // member, if any; and its direct and indirect base
2649  // classes. Its associated namespaces are the namespaces in
2650  // which its associated classes are defined.
2651  case Type::Record: {
2652  CXXRecordDecl *Class =
2653  cast<CXXRecordDecl>(cast<RecordType>(T)->getDecl());
2654  addAssociatedClassesAndNamespaces(Result, Class);
2655  break;
2656  }
2657 
2658  // -- If T is an enumeration type, its associated namespace is
2659  // the namespace in which it is defined. If it is class
2660  // member, its associated class is the member's class; else
2661  // it has no associated class.
2662  case Type::Enum: {
2663  EnumDecl *Enum = cast<EnumType>(T)->getDecl();
2664 
2665  DeclContext *Ctx = Enum->getDeclContext();
2666  if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
2667  Result.Classes.insert(EnclosingClass);
2668 
2669  // Add the associated namespace for this class.
2670  CollectEnclosingNamespace(Result.Namespaces, Ctx);
2671 
2672  break;
2673  }
2674 
2675  // -- If T is a function type, its associated namespaces and
2676  // classes are those associated with the function parameter
2677  // types and those associated with the return type.
2678  case Type::FunctionProto: {
2679  const FunctionProtoType *Proto = cast<FunctionProtoType>(T);
2680  for (const auto &Arg : Proto->param_types())
2681  Queue.push_back(Arg.getTypePtr());
2682  // fallthrough
2683  LLVM_FALLTHROUGH;
2684  }
2685  case Type::FunctionNoProto: {
2686  const FunctionType *FnType = cast<FunctionType>(T);
2687  T = FnType->getReturnType().getTypePtr();
2688  continue;
2689  }
2690 
2691  // -- If T is a pointer to a member function of a class X, its
2692  // associated namespaces and classes are those associated
2693  // with the function parameter types and return type,
2694  // together with those associated with X.
2695  //
2696  // -- If T is a pointer to a data member of class X, its
2697  // associated namespaces and classes are those associated
2698  // with the member type together with those associated with
2699  // X.
2700  case Type::MemberPointer: {
2701  const MemberPointerType *MemberPtr = cast<MemberPointerType>(T);
2702 
2703  // Queue up the class type into which this points.
2704  Queue.push_back(MemberPtr->getClass());
2705 
2706  // And directly continue with the pointee type.
2707  T = MemberPtr->getPointeeType().getTypePtr();
2708  continue;
2709  }
2710 
2711  // As an extension, treat this like a normal pointer.
2712  case Type::BlockPointer:
2713  T = cast<BlockPointerType>(T)->getPointeeType().getTypePtr();
2714  continue;
2715 
2716  // References aren't covered by the standard, but that's such an
2717  // obvious defect that we cover them anyway.
2718  case Type::LValueReference:
2719  case Type::RValueReference:
2720  T = cast<ReferenceType>(T)->getPointeeType().getTypePtr();
2721  continue;
2722 
2723  // These are fundamental types.
2724  case Type::Vector:
2725  case Type::ExtVector:
2726  case Type::Complex:
2727  break;
2728 
2729  // Non-deduced auto types only get here for error cases.
2730  case Type::Auto:
2731  case Type::DeducedTemplateSpecialization:
2732  break;
2733 
2734  // If T is an Objective-C object or interface type, or a pointer to an
2735  // object or interface type, the associated namespace is the global
2736  // namespace.
2737  case Type::ObjCObject:
2738  case Type::ObjCInterface:
2739  case Type::ObjCObjectPointer:
2740  Result.Namespaces.insert(Result.S.Context.getTranslationUnitDecl());
2741  break;
2742 
2743  // Atomic types are just wrappers; use the associations of the
2744  // contained type.
2745  case Type::Atomic:
2746  T = cast<AtomicType>(T)->getValueType().getTypePtr();
2747  continue;
2748  case Type::Pipe:
2749  T = cast<PipeType>(T)->getElementType().getTypePtr();
2750  continue;
2751  }
2752 
2753  if (Queue.empty())
2754  break;
2755  T = Queue.pop_back_val();
2756  }
2757 }
2758 
2759 /// Find the associated classes and namespaces for
2760 /// argument-dependent lookup for a call with the given set of
2761 /// arguments.
2762 ///
2763 /// This routine computes the sets of associated classes and associated
2764 /// namespaces searched by argument-dependent lookup
2765 /// (C++ [basic.lookup.argdep]) for a given set of arguments.
2767  SourceLocation InstantiationLoc, ArrayRef<Expr *> Args,
2768  AssociatedNamespaceSet &AssociatedNamespaces,
2769  AssociatedClassSet &AssociatedClasses) {
2770  AssociatedNamespaces.clear();
2771  AssociatedClasses.clear();
2772 
2773  AssociatedLookup Result(*this, InstantiationLoc,
2774  AssociatedNamespaces, AssociatedClasses);
2775 
2776  // C++ [basic.lookup.koenig]p2:
2777  // For each argument type T in the function call, there is a set
2778  // of zero or more associated namespaces and a set of zero or more
2779  // associated classes to be considered. The sets of namespaces and
2780  // classes is determined entirely by the types of the function
2781  // arguments (and the namespace of any template template
2782  // argument).
2783  for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
2784  Expr *Arg = Args[ArgIdx];
2785 
2786  if (Arg->getType() != Context.OverloadTy) {
2788  continue;
2789  }
2790 
2791  // [...] In addition, if the argument is the name or address of a
2792  // set of overloaded functions and/or function templates, its
2793  // associated classes and namespaces are the union of those
2794  // associated with each of the members of the set: the namespace
2795  // in which the function or function template is defined and the
2796  // classes and namespaces associated with its (non-dependent)
2797  // parameter types and return type.
2798  Arg = Arg->IgnoreParens();
2799  if (UnaryOperator *unaryOp = dyn_cast<UnaryOperator>(Arg))
2800  if (unaryOp->getOpcode() == UO_AddrOf)
2801  Arg = unaryOp->getSubExpr();
2802 
2803  UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Arg);
2804  if (!ULE) continue;
2805 
2806  for (const auto *D : ULE->decls()) {
2807  // Look through any using declarations to find the underlying function.
2808  const FunctionDecl *FDecl = D->getUnderlyingDecl()->getAsFunction();
2809 
2810  // Add the classes and namespaces associated with the parameter
2811  // types and return type of this function.
2812  addAssociatedClassesAndNamespaces(Result, FDecl->getType());
2813  }
2814  }
2815 }
2816 
2818  SourceLocation Loc,
2819  LookupNameKind NameKind,
2820  RedeclarationKind Redecl) {
2821  LookupResult R(*this, Name, Loc, NameKind, Redecl);
2822  LookupName(R, S);
2823  return R.getAsSingle<NamedDecl>();
2824 }
2825 
2826 /// Find the protocol with the given name, if any.
2828  SourceLocation IdLoc,
2829  RedeclarationKind Redecl) {
2830  Decl *D = LookupSingleName(TUScope, II, IdLoc,
2831  LookupObjCProtocolName, Redecl);
2832  return cast_or_null<ObjCProtocolDecl>(D);
2833 }
2834 
2836  QualType T1, QualType T2,
2837  UnresolvedSetImpl &Functions) {
2838  // C++ [over.match.oper]p3:
2839  // -- The set of non-member candidates is the result of the
2840  // unqualified lookup of operator@ in the context of the
2841  // expression according to the usual rules for name lookup in
2842  // unqualified function calls (3.4.2) except that all member
2843  // functions are ignored.
2845  LookupResult Operators(*this, OpName, SourceLocation(), LookupOperatorName);
2846  LookupName(Operators, S);
2847 
2848  assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous");
2849  Functions.append(Operators.begin(), Operators.end());
2850 }
2851 
2854  bool ConstArg,
2855  bool VolatileArg,
2856  bool RValueThis,
2857  bool ConstThis,
2858  bool VolatileThis) {
2859  assert(CanDeclareSpecialMemberFunction(RD) &&
2860  "doing special member lookup into record that isn't fully complete");
2861  RD = RD->getDefinition();
2862  if (RValueThis || ConstThis || VolatileThis)
2863  assert((SM == CXXCopyAssignment || SM == CXXMoveAssignment) &&
2864  "constructors and destructors always have unqualified lvalue this");
2865  if (ConstArg || VolatileArg)
2866  assert((SM != CXXDefaultConstructor && SM != CXXDestructor) &&
2867  "parameter-less special members can't have qualified arguments");
2868 
2869  // FIXME: Get the caller to pass in a location for the lookup.
2870  SourceLocation LookupLoc = RD->getLocation();
2871 
2872  llvm::FoldingSetNodeID ID;
2873  ID.AddPointer(RD);
2874  ID.AddInteger(SM);
2875  ID.AddInteger(ConstArg);
2876  ID.AddInteger(VolatileArg);
2877  ID.AddInteger(RValueThis);
2878  ID.AddInteger(ConstThis);
2879  ID.AddInteger(VolatileThis);
2880 
2881  void *InsertPoint;
2883  SpecialMemberCache.FindNodeOrInsertPos(ID, InsertPoint);
2884 
2885  // This was already cached
2886  if (Result)
2887  return *Result;
2888 
2889  Result = BumpAlloc.Allocate<SpecialMemberOverloadResultEntry>();
2890  Result = new (Result) SpecialMemberOverloadResultEntry(ID);
2891  SpecialMemberCache.InsertNode(Result, InsertPoint);
2892 
2893  if (SM == CXXDestructor) {
2894  if (RD->needsImplicitDestructor())
2895  DeclareImplicitDestructor(RD);
2896  CXXDestructorDecl *DD = RD->getDestructor();
2897  assert(DD && "record without a destructor");
2898  Result->setMethod(DD);
2899  Result->setKind(DD->isDeleted() ?
2900  SpecialMemberOverloadResult::NoMemberOrDeleted :
2901  SpecialMemberOverloadResult::Success);
2902  return *Result;
2903  }
2904 
2905  // Prepare for overload resolution. Here we construct a synthetic argument
2906  // if necessary and make sure that implicit functions are declared.
2907  CanQualType CanTy = Context.getCanonicalType(Context.getTagDeclType(RD));
2908  DeclarationName Name;
2909  Expr *Arg = nullptr;
2910  unsigned NumArgs;
2911 
2912  QualType ArgType = CanTy;
2913  ExprValueKind VK = VK_LValue;
2914 
2915  if (SM == CXXDefaultConstructor) {
2916  Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
2917  NumArgs = 0;
2919  DeclareImplicitDefaultConstructor(RD);
2920  } else {
2921  if (SM == CXXCopyConstructor || SM == CXXMoveConstructor) {
2922  Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
2923  if (RD->needsImplicitCopyConstructor())
2924  DeclareImplicitCopyConstructor(RD);
2925  if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveConstructor())
2926  DeclareImplicitMoveConstructor(RD);
2927  } else {
2928  Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
2929  if (RD->needsImplicitCopyAssignment())
2930  DeclareImplicitCopyAssignment(RD);
2931  if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveAssignment())
2932  DeclareImplicitMoveAssignment(RD);
2933  }
2934 
2935  if (ConstArg)
2936  ArgType.addConst();
2937  if (VolatileArg)
2938  ArgType.addVolatile();
2939 
2940  // This isn't /really/ specified by the standard, but it's implied
2941  // we should be working from an RValue in the case of move to ensure
2942  // that we prefer to bind to rvalue references, and an LValue in the
2943  // case of copy to ensure we don't bind to rvalue references.
2944  // Possibly an XValue is actually correct in the case of move, but
2945  // there is no semantic difference for class types in this restricted
2946  // case.
2947  if (SM == CXXCopyConstructor || SM == CXXCopyAssignment)
2948  VK = VK_LValue;
2949  else
2950  VK = VK_RValue;
2951  }
2952 
2953  OpaqueValueExpr FakeArg(LookupLoc, ArgType, VK);
2954 
2955  if (SM != CXXDefaultConstructor) {
2956  NumArgs = 1;
2957  Arg = &FakeArg;
2958  }
2959 
2960  // Create the object argument
2961  QualType ThisTy = CanTy;
2962  if (ConstThis)
2963  ThisTy.addConst();
2964  if (VolatileThis)
2965  ThisTy.addVolatile();
2966  Expr::Classification Classification =
2967  OpaqueValueExpr(LookupLoc, ThisTy,
2968  RValueThis ? VK_RValue : VK_LValue).Classify(Context);
2969 
2970  // Now we perform lookup on the name we computed earlier and do overload
2971  // resolution. Lookup is only performed directly into the class since there
2972  // will always be a (possibly implicit) declaration to shadow any others.
2974  DeclContext::lookup_result R = RD->lookup(Name);
2975 
2976  if (R.empty()) {
2977  // We might have no default constructor because we have a lambda's closure
2978  // type, rather than because there's some other declared constructor.
2979  // Every class has a copy/move constructor, copy/move assignment, and
2980  // destructor.
2981  assert(SM == CXXDefaultConstructor &&
2982  "lookup for a constructor or assignment operator was empty");
2983  Result->setMethod(nullptr);
2984  Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
2985  return *Result;
2986  }
2987 
2988  // Copy the candidates as our processing of them may load new declarations
2989  // from an external source and invalidate lookup_result.
2990  SmallVector<NamedDecl *, 8> Candidates(R.begin(), R.end());
2991 
2992  for (NamedDecl *CandDecl : Candidates) {
2993  if (CandDecl->isInvalidDecl())
2994  continue;
2995 
2996  DeclAccessPair Cand = DeclAccessPair::make(CandDecl, AS_public);
2997  auto CtorInfo = getConstructorInfo(Cand);
2998  if (CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(Cand->getUnderlyingDecl())) {
2999  if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
3000  AddMethodCandidate(M, Cand, RD, ThisTy, Classification,
3001  llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
3002  else if (CtorInfo)
3003  AddOverloadCandidate(CtorInfo.Constructor, CtorInfo.FoundDecl,
3004  llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
3005  else
3006  AddOverloadCandidate(M, Cand, llvm::makeArrayRef(&Arg, NumArgs), OCS,
3007  true);
3008  } else if (FunctionTemplateDecl *Tmpl =
3009  dyn_cast<FunctionTemplateDecl>(Cand->getUnderlyingDecl())) {
3010  if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
3011  AddMethodTemplateCandidate(
3012  Tmpl, Cand, RD, nullptr, ThisTy, Classification,
3013  llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
3014  else if (CtorInfo)
3015  AddTemplateOverloadCandidate(
3016  CtorInfo.ConstructorTmpl, CtorInfo.FoundDecl, nullptr,
3017  llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
3018  else
3019  AddTemplateOverloadCandidate(
3020  Tmpl, Cand, nullptr, llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
3021  } else {
3022  assert(isa<UsingDecl>(Cand.getDecl()) &&
3023  "illegal Kind of operator = Decl");
3024  }
3025  }
3026 
3028  switch (OCS.BestViableFunction(*this, LookupLoc, Best)) {
3029  case OR_Success:
3030  Result->setMethod(cast<CXXMethodDecl>(Best->Function));
3031  Result->setKind(SpecialMemberOverloadResult::Success);
3032  break;
3033 
3034  case OR_Deleted:
3035  Result->setMethod(cast<CXXMethodDecl>(Best->Function));
3036  Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
3037  break;
3038 
3039  case OR_Ambiguous:
3040  Result->setMethod(nullptr);
3041  Result->setKind(SpecialMemberOverloadResult::Ambiguous);
3042  break;
3043 
3044  case OR_No_Viable_Function:
3045  Result->setMethod(nullptr);
3046  Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
3047  break;
3048  }
3049 
3050  return *Result;
3051 }
3052 
3053 /// Look up the default constructor for the given class.
3056  LookupSpecialMember(Class, CXXDefaultConstructor, false, false, false,
3057  false, false);
3058 
3059  return cast_or_null<CXXConstructorDecl>(Result.getMethod());
3060 }
3061 
3062 /// Look up the copying constructor for the given class.
3064  unsigned Quals) {
3065  assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3066  "non-const, non-volatile qualifiers for copy ctor arg");
3068  LookupSpecialMember(Class, CXXCopyConstructor, Quals & Qualifiers::Const,
3069  Quals & Qualifiers::Volatile, false, false, false);
3070 
3071  return cast_or_null<CXXConstructorDecl>(Result.getMethod());
3072 }
3073 
3074 /// Look up the moving constructor for the given class.
3076  unsigned Quals) {
3078  LookupSpecialMember(Class, CXXMoveConstructor, Quals & Qualifiers::Const,
3079  Quals & Qualifiers::Volatile, false, false, false);
3080 
3081  return cast_or_null<CXXConstructorDecl>(Result.getMethod());
3082 }
3083 
3084 /// Look up the constructors for the given class.
3086  // If the implicit constructors have not yet been declared, do so now.
3087  if (CanDeclareSpecialMemberFunction(Class)) {
3088  if (Class->needsImplicitDefaultConstructor())
3089  DeclareImplicitDefaultConstructor(Class);
3090  if (Class->needsImplicitCopyConstructor())
3091  DeclareImplicitCopyConstructor(Class);
3092  if (getLangOpts().CPlusPlus11 && Class->needsImplicitMoveConstructor())
3093  DeclareImplicitMoveConstructor(Class);
3094  }
3095 
3096  CanQualType T = Context.getCanonicalType(Context.getTypeDeclType(Class));
3098  return Class->lookup(Name);
3099 }
3100 
3101 /// Look up the copying assignment operator for the given class.
3103  unsigned Quals, bool RValueThis,
3104  unsigned ThisQuals) {
3105  assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3106  "non-const, non-volatile qualifiers for copy assignment arg");
3107  assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3108  "non-const, non-volatile qualifiers for copy assignment this");
3110  LookupSpecialMember(Class, CXXCopyAssignment, Quals & Qualifiers::Const,
3111  Quals & Qualifiers::Volatile, RValueThis,
3112  ThisQuals & Qualifiers::Const,
3113  ThisQuals & Qualifiers::Volatile);
3114 
3115  return Result.getMethod();
3116 }
3117 
3118 /// Look up the moving assignment operator for the given class.
3120  unsigned Quals,
3121  bool RValueThis,
3122  unsigned ThisQuals) {
3123  assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&
3124  "non-const, non-volatile qualifiers for copy assignment this");
3126  LookupSpecialMember(Class, CXXMoveAssignment, Quals & Qualifiers::Const,
3127  Quals & Qualifiers::Volatile, RValueThis,
3128  ThisQuals & Qualifiers::Const,
3129  ThisQuals & Qualifiers::Volatile);
3130 
3131  return Result.getMethod();
3132 }
3133 
3134 /// Look for the destructor of the given class.
3135 ///
3136 /// During semantic analysis, this routine should be used in lieu of
3137 /// CXXRecordDecl::getDestructor().
3138 ///
3139 /// \returns The destructor for this class.
3141  return cast<CXXDestructorDecl>(LookupSpecialMember(Class, CXXDestructor,
3142  false, false, false,
3143  false, false).getMethod());
3144 }
3145 
3146 /// LookupLiteralOperator - Determine which literal operator should be used for
3147 /// a user-defined literal, per C++11 [lex.ext].
3148 ///
3149 /// Normal overload resolution is not used to select which literal operator to
3150 /// call for a user-defined literal. Look up the provided literal operator name,
3151 /// and filter the results to the appropriate set for the given argument types.
3154  ArrayRef<QualType> ArgTys,
3155  bool AllowRaw, bool AllowTemplate,
3156  bool AllowStringTemplate, bool DiagnoseMissing) {
3157  LookupName(R, S);
3158  assert(R.getResultKind() != LookupResult::Ambiguous &&
3159  "literal operator lookup can't be ambiguous");
3160 
3161  // Filter the lookup results appropriately.
3163 
3164  bool FoundRaw = false;
3165  bool FoundTemplate = false;
3166  bool FoundStringTemplate = false;
3167  bool FoundExactMatch = false;
3168 
3169  while (F.hasNext()) {
3170  Decl *D = F.next();
3171  if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(D))
3172  D = USD->getTargetDecl();
3173 
3174  // If the declaration we found is invalid, skip it.
3175  if (D->isInvalidDecl()) {
3176  F.erase();
3177  continue;
3178  }
3179 
3180  bool IsRaw = false;
3181  bool IsTemplate = false;
3182  bool IsStringTemplate = false;
3183  bool IsExactMatch = false;
3184 
3185  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
3186  if (FD->getNumParams() == 1 &&
3187  FD->getParamDecl(0)->getType()->getAs<PointerType>())
3188  IsRaw = true;
3189  else if (FD->getNumParams() == ArgTys.size()) {
3190  IsExactMatch = true;
3191  for (unsigned ArgIdx = 0; ArgIdx != ArgTys.size(); ++ArgIdx) {
3192  QualType ParamTy = FD->getParamDecl(ArgIdx)->getType();
3193  if (!Context.hasSameUnqualifiedType(ArgTys[ArgIdx], ParamTy)) {
3194  IsExactMatch = false;
3195  break;
3196  }
3197  }
3198  }
3199  }
3200  if (FunctionTemplateDecl *FD = dyn_cast<FunctionTemplateDecl>(D)) {
3201  TemplateParameterList *Params = FD->getTemplateParameters();
3202  if (Params->size() == 1)
3203  IsTemplate = true;
3204  else
3205  IsStringTemplate = true;
3206  }
3207 
3208  if (IsExactMatch) {
3209  FoundExactMatch = true;
3210  AllowRaw = false;
3211  AllowTemplate = false;
3212  AllowStringTemplate = false;
3213  if (FoundRaw || FoundTemplate || FoundStringTemplate) {
3214  // Go through again and remove the raw and template decls we've
3215  // already found.
3216  F.restart();
3217  FoundRaw = FoundTemplate = FoundStringTemplate = false;
3218  }
3219  } else if (AllowRaw && IsRaw) {
3220  FoundRaw = true;
3221  } else if (AllowTemplate && IsTemplate) {
3222  FoundTemplate = true;
3223  } else if (AllowStringTemplate && IsStringTemplate) {
3224  FoundStringTemplate = true;
3225  } else {
3226  F.erase();
3227  }
3228  }
3229 
3230  F.done();
3231 
3232  // C++11 [lex.ext]p3, p4: If S contains a literal operator with a matching
3233  // parameter type, that is used in preference to a raw literal operator
3234  // or literal operator template.
3235  if (FoundExactMatch)
3236  return LOLR_Cooked;
3237 
3238  // C++11 [lex.ext]p3, p4: S shall contain a raw literal operator or a literal
3239  // operator template, but not both.
3240  if (FoundRaw && FoundTemplate) {
3241  Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call) << R.getLookupName();
3242  for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
3243  NoteOverloadCandidate(*I, (*I)->getUnderlyingDecl()->getAsFunction());
3244  return LOLR_Error;
3245  }
3246 
3247  if (FoundRaw)
3248  return LOLR_Raw;
3249 
3250  if (FoundTemplate)
3251  return LOLR_Template;
3252 
3253  if (FoundStringTemplate)
3254  return LOLR_StringTemplate;
3255 
3256  // Didn't find anything we could use.
3257  if (DiagnoseMissing) {
3258  Diag(R.getNameLoc(), diag::err_ovl_no_viable_literal_operator)
3259  << R.getLookupName() << (int)ArgTys.size() << ArgTys[0]
3260  << (ArgTys.size() == 2 ? ArgTys[1] : QualType()) << AllowRaw
3261  << (AllowTemplate || AllowStringTemplate);
3262  return LOLR_Error;
3263  }
3264 
3265  return LOLR_ErrorNoDiagnostic;
3266 }
3267 
3269  NamedDecl *&Old = Decls[cast<NamedDecl>(New->getCanonicalDecl())];
3270 
3271  // If we haven't yet seen a decl for this key, or the last decl
3272  // was exactly this one, we're done.
3273  if (Old == nullptr || Old == New) {
3274  Old = New;
3275  return;
3276  }
3277 
3278  // Otherwise, decide which is a more recent redeclaration.
3279  FunctionDecl *OldFD = Old->getAsFunction();
3280  FunctionDecl *NewFD = New->getAsFunction();
3281 
3282  FunctionDecl *Cursor = NewFD;
3283  while (true) {
3284  Cursor = Cursor->getPreviousDecl();
3285 
3286  // If we got to the end without finding OldFD, OldFD is the newer
3287  // declaration; leave things as they are.
3288  if (!Cursor) return;
3289 
3290  // If we do find OldFD, then NewFD is newer.
3291  if (Cursor == OldFD) break;
3292 
3293  // Otherwise, keep looking.
3294  }
3295 
3296  Old = New;
3297 }
3298 
3300  ArrayRef<Expr *> Args, ADLResult &Result) {
3301  // Find all of the associated namespaces and classes based on the
3302  // arguments we have.
3303  AssociatedNamespaceSet AssociatedNamespaces;
3304  AssociatedClassSet AssociatedClasses;
3305  FindAssociatedClassesAndNamespaces(Loc, Args,
3306  AssociatedNamespaces,
3307  AssociatedClasses);
3308 
3309  // C++ [basic.lookup.argdep]p3:
3310  // Let X be the lookup set produced by unqualified lookup (3.4.1)
3311  // and let Y be the lookup set produced by argument dependent
3312  // lookup (defined as follows). If X contains [...] then Y is
3313  // empty. Otherwise Y is the set of declarations found in the
3314  // namespaces associated with the argument types as described
3315  // below. The set of declarations found by the lookup of the name
3316  // is the union of X and Y.
3317  //
3318  // Here, we compute Y and add its members to the overloaded
3319  // candidate set.
3320  for (auto *NS : AssociatedNamespaces) {
3321  // When considering an associated namespace, the lookup is the
3322  // same as the lookup performed when the associated namespace is
3323  // used as a qualifier (3.4.3.2) except that:
3324  //
3325  // -- Any using-directives in the associated namespace are
3326  // ignored.
3327  //
3328  // -- Any namespace-scope friend functions declared in
3329  // associated classes are visible within their respective
3330  // namespaces even if they are not visible during an ordinary
3331  // lookup (11.4).
3332  DeclContext::lookup_result R = NS->lookup(Name);
3333  for (auto *D : R) {
3334  auto *Underlying = D;
3335  if (auto *USD = dyn_cast<UsingShadowDecl>(D))
3336  Underlying = USD->getTargetDecl();
3337 
3338  if (!isa<FunctionDecl>(Underlying) &&
3339  !isa<FunctionTemplateDecl>(Underlying))
3340  continue;
3341 
3342  if (!isVisible(D)) {
3343  D = findAcceptableDecl(
3345  if (!D)
3346  continue;
3347  if (auto *USD = dyn_cast<UsingShadowDecl>(D))
3348  Underlying = USD->getTargetDecl();
3349  }
3350 
3351  // If the only declaration here is an ordinary friend, consider
3352  // it only if it was declared in an associated classes.
3353  if ((D->getIdentifierNamespace() & Decl::IDNS_Ordinary) == 0) {
3354  // If it's neither ordinarily visible nor a friend, we can't find it.
3356  continue;
3357 
3358  bool DeclaredInAssociatedClass = false;
3359  for (Decl *DI = D; DI; DI = DI->getPreviousDecl()) {
3360  DeclContext *LexDC = DI->getLexicalDeclContext();
3361  if (isa<CXXRecordDecl>(LexDC) &&
3362  AssociatedClasses.count(cast<CXXRecordDecl>(LexDC)) &&
3363  isVisible(cast<NamedDecl>(DI))) {
3364  DeclaredInAssociatedClass = true;
3365  break;
3366  }
3367  }
3368  if (!DeclaredInAssociatedClass)
3369  continue;
3370  }
3371 
3372  // FIXME: Preserve D as the FoundDecl.
3373  Result.insert(Underlying);
3374  }
3375  }
3376 }
3377 
3378 //----------------------------------------------------------------------------
3379 // Search for all visible declarations.
3380 //----------------------------------------------------------------------------
3382 
3383 bool VisibleDeclConsumer::includeHiddenDecls() const { return false; }
3384 
3385 namespace {
3386 
3387 class ShadowContextRAII;
3388 
3389 class VisibleDeclsRecord {
3390 public:
3391  /// An entry in the shadow map, which is optimized to store a
3392  /// single declaration (the common case) but can also store a list
3393  /// of declarations.
3394  typedef llvm::TinyPtrVector<NamedDecl*> ShadowMapEntry;
3395 
3396 private:
3397  /// A mapping from declaration names to the declarations that have
3398  /// this name within a particular scope.
3399  typedef llvm::DenseMap<DeclarationName, ShadowMapEntry> ShadowMap;
3400 
3401  /// A list of shadow maps, which is used to model name hiding.
3402  std::list<ShadowMap> ShadowMaps;
3403 
3404  /// The declaration contexts we have already visited.
3405  llvm::SmallPtrSet<DeclContext *, 8> VisitedContexts;
3406 
3407  friend class ShadowContextRAII;
3408 
3409 public:
3410  /// Determine whether we have already visited this context
3411  /// (and, if not, note that we are going to visit that context now).
3412  bool visitedContext(DeclContext *Ctx) {
3413  return !VisitedContexts.insert(Ctx).second;
3414  }
3415 
3416  bool alreadyVisitedContext(DeclContext *Ctx) {
3417  return VisitedContexts.count(Ctx);
3418  }
3419 
3420  /// Determine whether the given declaration is hidden in the
3421  /// current scope.
3422  ///
3423  /// \returns the declaration that hides the given declaration, or
3424  /// NULL if no such declaration exists.
3425  NamedDecl *checkHidden(NamedDecl *ND);
3426 
3427  /// Add a declaration to the current shadow map.
3428  void add(NamedDecl *ND) {
3429  ShadowMaps.back()[ND->getDeclName()].push_back(ND);
3430  }
3431 };
3432 
3433 /// RAII object that records when we've entered a shadow context.
3434 class ShadowContextRAII {
3435  VisibleDeclsRecord &Visible;
3436 
3437  typedef VisibleDeclsRecord::ShadowMap ShadowMap;
3438 
3439 public:
3440  ShadowContextRAII(VisibleDeclsRecord &Visible) : Visible(Visible) {
3441  Visible.ShadowMaps.emplace_back();
3442  }
3443 
3444  ~ShadowContextRAII() {
3445  Visible.ShadowMaps.pop_back();
3446  }
3447 };
3448 
3449 } // end anonymous namespace
3450 
3451 NamedDecl *VisibleDeclsRecord::checkHidden(NamedDecl *ND) {
3452  unsigned IDNS = ND->getIdentifierNamespace();
3453  std::list<ShadowMap>::reverse_iterator SM = ShadowMaps.rbegin();
3454  for (std::list<ShadowMap>::reverse_iterator SMEnd = ShadowMaps.rend();
3455  SM != SMEnd; ++SM) {
3456  ShadowMap::iterator Pos = SM->find(ND->getDeclName());
3457  if (Pos == SM->end())
3458  continue;
3459 
3460  for (auto *D : Pos->second) {
3461  // A tag declaration does not hide a non-tag declaration.
3462  if (D->hasTagIdentifierNamespace() &&
3465  continue;
3466 
3467  // Protocols are in distinct namespaces from everything else.
3469  || (IDNS & Decl::IDNS_ObjCProtocol)) &&
3470  D->getIdentifierNamespace() != IDNS)
3471  continue;
3472 
3473  // Functions and function templates in the same scope overload
3474  // rather than hide. FIXME: Look for hiding based on function
3475  // signatures!
3478  SM == ShadowMaps.rbegin())
3479  continue;
3480 
3481  // A shadow declaration that's created by a resolved using declaration
3482  // is not hidden by the same using declaration.
3483  if (isa<UsingShadowDecl>(ND) && isa<UsingDecl>(D) &&
3484  cast<UsingShadowDecl>(ND)->getUsingDecl() == D)
3485  continue;
3486 
3487  // We've found a declaration that hides this one.
3488  return D;
3489  }
3490  }
3491 
3492  return nullptr;
3493 }
3494 
3495 static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
3496  bool QualifiedNameLookup,
3497  bool InBaseClass,
3498  VisibleDeclConsumer &Consumer,
3499  VisibleDeclsRecord &Visited,
3500  bool IncludeDependentBases,
3501  bool LoadExternal) {
3502  if (!Ctx)
3503  return;
3504 
3505  // Make sure we don't visit the same context twice.
3506  if (Visited.visitedContext(Ctx->getPrimaryContext()))
3507  return;
3508 
3509  Consumer.EnteredContext(Ctx);
3510 
3511  // Outside C++, lookup results for the TU live on identifiers.
3512  if (isa<TranslationUnitDecl>(Ctx) &&
3513  !Result.getSema().getLangOpts().CPlusPlus) {
3514  auto &S = Result.getSema();
3515  auto &Idents = S.Context.Idents;
3516 
3517  // Ensure all external identifiers are in the identifier table.
3518  if (LoadExternal)
3519  if (IdentifierInfoLookup *External = Idents.getExternalIdentifierLookup()) {
3520  std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
3521  for (StringRef Name = Iter->Next(); !Name.empty(); Name = Iter->Next())
3522  Idents.get(Name);
3523  }
3524 
3525  // Walk all lookup results in the TU for each identifier.
3526  for (const auto &Ident : Idents) {
3527  for (auto I = S.IdResolver.begin(Ident.getValue()),
3528  E = S.IdResolver.end();
3529  I != E; ++I) {
3530  if (S.IdResolver.isDeclInScope(*I, Ctx)) {
3531  if (NamedDecl *ND = Result.getAcceptableDecl(*I)) {
3532  Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
3533  Visited.add(ND);
3534  }
3535  }
3536  }
3537  }
3538 
3539  return;
3540  }
3541 
3542  if (CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(Ctx))
3544 
3545  // We sometimes skip loading namespace-level results (they tend to be huge).
3546  bool Load = LoadExternal ||
3547  !(isa<TranslationUnitDecl>(Ctx) || isa<NamespaceDecl>(Ctx));
3548  // Enumerate all of the results in this context.
3549  for (DeclContextLookupResult R :
3550  Load ? Ctx->lookups()
3551  : Ctx->noload_lookups(/*PreserveInternalState=*/false)) {
3552  for (auto *D : R) {
3553  if (auto *ND = Result.getAcceptableDecl(D)) {
3554  Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
3555  Visited.add(ND);
3556  }
3557  }
3558  }
3559 
3560  // Traverse using directives for qualified name lookup.
3561  if (QualifiedNameLookup) {
3562  ShadowContextRAII Shadow(Visited);
3563  for (auto I : Ctx->using_directives()) {
3564  if (!Result.getSema().isVisible(I))
3565  continue;
3566  LookupVisibleDecls(I->getNominatedNamespace(), Result,
3567  QualifiedNameLookup, InBaseClass, Consumer, Visited,
3568  IncludeDependentBases, LoadExternal);
3569  }
3570  }
3571 
3572  // Traverse the contexts of inherited C++ classes.
3573  if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) {
3574  if (!Record->hasDefinition())
3575  return;
3576 
3577  for (const auto &B : Record->bases()) {
3578  QualType BaseType = B.getType();
3579 
3580  RecordDecl *RD;
3581  if (BaseType->isDependentType()) {
3582  if (!IncludeDependentBases) {
3583  // Don't look into dependent bases, because name lookup can't look
3584  // there anyway.
3585  continue;
3586  }
3587  const auto *TST = BaseType->getAs<TemplateSpecializationType>();
3588  if (!TST)
3589  continue;
3590  TemplateName TN = TST->getTemplateName();
3591  const auto *TD =
3592  dyn_cast_or_null<ClassTemplateDecl>(TN.getAsTemplateDecl());
3593  if (!TD)
3594  continue;
3595  RD = TD->getTemplatedDecl();
3596  } else {
3597  const auto *Record = BaseType->getAs<RecordType>();
3598  if (!Record)
3599  continue;
3600  RD = Record->getDecl();
3601  }
3602 
3603  // FIXME: It would be nice to be able to determine whether referencing
3604  // a particular member would be ambiguous. For example, given
3605  //
3606  // struct A { int member; };
3607  // struct B { int member; };
3608  // struct C : A, B { };
3609  //
3610  // void f(C *c) { c->### }
3611  //
3612  // accessing 'member' would result in an ambiguity. However, we
3613  // could be smart enough to qualify the member with the base
3614  // class, e.g.,
3615  //
3616  // c->B::member
3617  //
3618  // or
3619  //
3620  // c->A::member
3621 
3622  // Find results in this base class (and its bases).
3623  ShadowContextRAII Shadow(Visited);
3624  LookupVisibleDecls(RD, Result, QualifiedNameLookup, true, Consumer,
3625  Visited, IncludeDependentBases, LoadExternal);
3626  }
3627  }
3628 
3629  // Traverse the contexts of Objective-C classes.
3630  if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(Ctx)) {
3631  // Traverse categories.
3632  for (auto *Cat : IFace->visible_categories()) {
3633  ShadowContextRAII Shadow(Visited);
3634  LookupVisibleDecls(Cat, Result, QualifiedNameLookup, false, Consumer,
3635  Visited, IncludeDependentBases, LoadExternal);
3636  }
3637 
3638  // Traverse protocols.
3639  for (auto *I : IFace->all_referenced_protocols()) {
3640  ShadowContextRAII Shadow(Visited);
3641  LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3642  Visited, IncludeDependentBases, LoadExternal);
3643  }
3644 
3645  // Traverse the superclass.
3646  if (IFace->getSuperClass()) {
3647  ShadowContextRAII Shadow(Visited);
3648  LookupVisibleDecls(IFace->getSuperClass(), Result, QualifiedNameLookup,
3649  true, Consumer, Visited, IncludeDependentBases,
3650  LoadExternal);
3651  }
3652 
3653  // If there is an implementation, traverse it. We do this to find
3654  // synthesized ivars.
3655  if (IFace->getImplementation()) {
3656  ShadowContextRAII Shadow(Visited);
3657  LookupVisibleDecls(IFace->getImplementation(), Result,
3658  QualifiedNameLookup, InBaseClass, Consumer, Visited,
3659  IncludeDependentBases, LoadExternal);
3660  }
3661  } else if (ObjCProtocolDecl *Protocol = dyn_cast<ObjCProtocolDecl>(Ctx)) {
3662  for (auto *I : Protocol->protocols()) {
3663  ShadowContextRAII Shadow(Visited);
3664  LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3665  Visited, IncludeDependentBases, LoadExternal);
3666  }
3667  } else if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(Ctx)) {
3668  for (auto *I : Category->protocols()) {
3669  ShadowContextRAII Shadow(Visited);
3670  LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
3671  Visited, IncludeDependentBases, LoadExternal);
3672  }
3673 
3674  // If there is an implementation, traverse it.
3675  if (Category->getImplementation()) {
3676  ShadowContextRAII Shadow(Visited);
3677  LookupVisibleDecls(Category->getImplementation(), Result,
3678  QualifiedNameLookup, true, Consumer, Visited,
3679  IncludeDependentBases, LoadExternal);
3680  }
3681  }
3682 }
3683 
3684 static void LookupVisibleDecls(Scope *S, LookupResult &Result,
3685  UnqualUsingDirectiveSet &UDirs,
3686  VisibleDeclConsumer &Consumer,
3687  VisibleDeclsRecord &Visited,
3688  bool LoadExternal) {
3689  if (!S)
3690  return;
3691 
3692  if (!S->getEntity() ||
3693  (!S->getParent() &&
3694  !Visited.alreadyVisitedContext(S->getEntity())) ||
3695  (S->getEntity())->isFunctionOrMethod()) {
3696  FindLocalExternScope FindLocals(Result);
3697  // Walk through the declarations in this Scope. The consumer might add new
3698  // decls to the scope as part of deserialization, so make a copy first.
3699  SmallVector<Decl *, 8> ScopeDecls(S->decls().begin(), S->decls().end());
3700  for (Decl *D : ScopeDecls) {
3701  if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
3702  if ((ND = Result.getAcceptableDecl(ND))) {
3703  Consumer.FoundDecl(ND, Visited.checkHidden(ND), nullptr, false);
3704  Visited.add(ND);
3705  }
3706  }
3707  }
3708 
3709  // FIXME: C++ [temp.local]p8
3710  DeclContext *Entity = nullptr;
3711  if (S->getEntity()) {
3712  // Look into this scope's declaration context, along with any of its
3713  // parent lookup contexts (e.g., enclosing classes), up to the point
3714  // where we hit the context stored in the next outer scope.
3715  Entity = S->getEntity();
3716  DeclContext *OuterCtx = findOuterContext(S).first; // FIXME
3717 
3718  for (DeclContext *Ctx = Entity; Ctx && !Ctx->Equals(OuterCtx);
3719  Ctx = Ctx->getLookupParent()) {
3720  if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
3721  if (Method->isInstanceMethod()) {
3722  // For instance methods, look for ivars in the method's interface.
3723  LookupResult IvarResult(Result.getSema(), Result.getLookupName(),
3725  if (ObjCInterfaceDecl *IFace = Method->getClassInterface()) {
3726  LookupVisibleDecls(IFace, IvarResult, /*QualifiedNameLookup=*/false,
3727  /*InBaseClass=*/false, Consumer, Visited,
3728  /*IncludeDependentBases=*/false, LoadExternal);
3729  }
3730  }
3731 
3732  // We've already performed all of the name lookup that we need
3733  // to for Objective-C methods; the next context will be the
3734  // outer scope.
3735  break;
3736  }
3737 
3738  if (Ctx->isFunctionOrMethod())
3739  continue;
3740 
3741  LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/false,
3742  /*InBaseClass=*/false, Consumer, Visited,
3743  /*IncludeDependentBases=*/false, LoadExternal);
3744  }
3745  } else if (!S->getParent()) {
3746  // Look into the translation unit scope. We walk through the translation
3747  // unit's declaration context, because the Scope itself won't have all of
3748  // the declarations if we loaded a precompiled header.
3749  // FIXME: We would like the translation unit's Scope object to point to the
3750  // translation unit, so we don't need this special "if" branch. However,
3751  // doing so would force the normal C++ name-lookup code to look into the
3752  // translation unit decl when the IdentifierInfo chains would suffice.
3753  // Once we fix that problem (which is part of a more general "don't look
3754  // in DeclContexts unless we have to" optimization), we can eliminate this.
3755  Entity = Result.getSema().Context.getTranslationUnitDecl();
3756  LookupVisibleDecls(Entity, Result, /*QualifiedNameLookup=*/false,
3757  /*InBaseClass=*/false, Consumer, Visited,
3758  /*IncludeDependentBases=*/false, LoadExternal);
3759  }
3760 
3761  if (Entity) {
3762  // Lookup visible declarations in any namespaces found by using
3763  // directives.
3764  for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(Entity))
3765  LookupVisibleDecls(const_cast<DeclContext *>(UUE.getNominatedNamespace()),
3766  Result, /*QualifiedNameLookup=*/false,
3767  /*InBaseClass=*/false, Consumer, Visited,
3768  /*IncludeDependentBases=*/false, LoadExternal);
3769  }
3770 
3771  // Lookup names in the parent scope.
3772  ShadowContextRAII Shadow(Visited);
3773  LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited,
3774  LoadExternal);
3775 }
3776 
3778  VisibleDeclConsumer &Consumer,
3779  bool IncludeGlobalScope, bool LoadExternal) {
3780  // Determine the set of using directives available during
3781  // unqualified name lookup.
3782  Scope *Initial = S;
3783  UnqualUsingDirectiveSet UDirs(*this);
3784  if (getLangOpts().CPlusPlus) {
3785  // Find the first namespace or translation-unit scope.
3786  while (S && !isNamespaceOrTranslationUnitScope(S))
3787  S = S->getParent();
3788 
3789  UDirs.visitScopeChain(Initial, S);
3790  }
3791  UDirs.done();
3792 
3793  // Look for visible declarations.
3794  LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
3795  Result.setAllowHidden(Consumer.includeHiddenDecls());
3796  VisibleDeclsRecord Visited;
3797  if (!IncludeGlobalScope)
3798  Visited.visitedContext(Context.getTranslationUnitDecl());
3799  ShadowContextRAII Shadow(Visited);
3800  ::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited, LoadExternal);
3801 }
3802 
3804  VisibleDeclConsumer &Consumer,
3805  bool IncludeGlobalScope,
3806  bool IncludeDependentBases, bool LoadExternal) {
3807  LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
3808  Result.setAllowHidden(Consumer.includeHiddenDecls());
3809  VisibleDeclsRecord Visited;
3810  if (!IncludeGlobalScope)
3811  Visited.visitedContext(Context.getTranslationUnitDecl());
3812  ShadowContextRAII Shadow(Visited);
3813  ::LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/true,
3814  /*InBaseClass=*/false, Consumer, Visited,
3815  IncludeDependentBases, LoadExternal);
3816 }
3817 
3818 /// LookupOrCreateLabel - Do a name lookup of a label with the specified name.
3819 /// If GnuLabelLoc is a valid source location, then this is a definition
3820 /// of an __label__ label name, otherwise it is a normal label definition
3821 /// or use.
3823  SourceLocation GnuLabelLoc) {
3824  // Do a lookup to see if we have a label with this name already.
3825  NamedDecl *Res = nullptr;
3826 
3827  if (GnuLabelLoc.isValid()) {
3828  // Local label definitions always shadow existing labels.
3829  Res = LabelDecl::Create(Context, CurContext, Loc, II, GnuLabelLoc);
3830  Scope *S = CurScope;
3831  PushOnScopeChains(Res, S, true);
3832  return cast<LabelDecl>(Res);
3833  }
3834 
3835  // Not a GNU local label.
3836  Res = LookupSingleName(CurScope, II, Loc, LookupLabel, NotForRedeclaration);
3837  // If we found a label, check to see if it is in the same context as us.
3838  // When in a Block, we don't want to reuse a label in an enclosing function.
3839  if (Res && Res->getDeclContext() != CurContext)
3840  Res = nullptr;
3841  if (!Res) {
3842  // If not forward referenced or defined already, create the backing decl.
3843  Res = LabelDecl::Create(Context, CurContext, Loc, II);
3844  Scope *S = CurScope->getFnParent();
3845  assert(S && "Not in a function?");
3846  PushOnScopeChains(Res, S, true);
3847  }
3848  return cast<LabelDecl>(Res);
3849 }
3850 
3851 //===----------------------------------------------------------------------===//
3852 // Typo correction
3853 //===----------------------------------------------------------------------===//
3854 
3856  TypoCorrection &Candidate) {
3857  Candidate.setCallbackDistance(CCC.RankCandidate(Candidate));
3858  return Candidate.getEditDistance(false) != TypoCorrection::InvalidDistance;
3859 }
3860 
3861 static void LookupPotentialTypoResult(Sema &SemaRef,
3862  LookupResult &Res,
3863  IdentifierInfo *Name,
3864  Scope *S, CXXScopeSpec *SS,
3866  bool EnteringContext,
3867  bool isObjCIvarLookup,
3868  bool FindHidden);
3869 
3870 /// Check whether the declarations found for a typo correction are
3871 /// visible. Set the correction's RequiresImport flag to true if none of the
3872 /// declarations are visible, false otherwise.
3873 static void checkCorrectionVisibility(Sema &SemaRef, TypoCorrection &TC) {
3874  TypoCorrection::decl_iterator DI = TC.begin(), DE = TC.end();
3875 
3876  for (/**/; DI != DE; ++DI)
3877  if (!LookupResult::isVisible(SemaRef, *DI))
3878  break;
3879  // No filtering needed if all decls are visible.
3880  if (DI == DE) {
3881  TC.setRequiresImport(false);
3882  return;
3883  }
3884 
3885  llvm::SmallVector<NamedDecl*, 4> NewDecls(TC.begin(), DI);
3886  bool AnyVisibleDecls = !NewDecls.empty();
3887 
3888  for (/**/; DI != DE; ++DI) {
3889  if (LookupResult::isVisible(SemaRef, *DI)) {
3890  if (!AnyVisibleDecls) {
3891  // Found a visible decl, discard all hidden ones.
3892  AnyVisibleDecls = true;
3893  NewDecls.clear();
3894  }
3895  NewDecls.push_back(*DI);
3896  } else if (!AnyVisibleDecls && !(*DI)->isModulePrivate())
3897  NewDecls.push_back(*DI);
3898  }
3899 
3900  if (NewDecls.empty())
3901  TC = TypoCorrection();
3902  else {
3903  TC.setCorrectionDecls(NewDecls);
3904  TC.setRequiresImport(!AnyVisibleDecls);
3905  }
3906 }
3907 
3908 // Fill the supplied vector with the IdentifierInfo pointers for each piece of
3909 // the given NestedNameSpecifier (i.e. given a NestedNameSpecifier "foo::bar::",
3910 // fill the vector with the IdentifierInfo pointers for "foo" and "bar").
3912  NestedNameSpecifier *NNS,
3914  if (NestedNameSpecifier *Prefix = NNS->getPrefix())
3915  getNestedNameSpecifierIdentifiers(Prefix, Identifiers);
3916  else
3917  Identifiers.clear();
3918 
3919  const IdentifierInfo *II = nullptr;
3920 
3921  switch (NNS->getKind()) {
3923  II = NNS->getAsIdentifier();
3924  break;
3925 
3927  if (NNS->getAsNamespace()->isAnonymousNamespace())
3928  return;
3929  II = NNS->getAsNamespace()->getIdentifier();
3930  break;
3931 
3933  II = NNS->getAsNamespaceAlias()->getIdentifier();
3934  break;
3935 
3938  II = QualType(NNS->getAsType(), 0).getBaseTypeIdentifier();
3939  break;
3940 
3943  return;
3944  }
3945 
3946  if (II)
3947  Identifiers.push_back(II);
3948 }
3949 
3951  DeclContext *Ctx, bool InBaseClass) {
3952  // Don't consider hidden names for typo correction.
3953  if (Hiding)
3954  return;
3955 
3956  // Only consider entities with identifiers for names, ignoring
3957  // special names (constructors, overloaded operators, selectors,
3958  // etc.).
3959  IdentifierInfo *Name = ND->getIdentifier();
3960  if (!Name)
3961  return;
3962 
3963  // Only consider visible declarations and declarations from modules with
3964  // names that exactly match.
3965  if (!LookupResult::isVisible(SemaRef, ND) && Name != Typo)
3966  return;
3967 
3968  FoundName(Name->getName());
3969 }
3970 
3972  // Compute the edit distance between the typo and the name of this
3973  // entity, and add the identifier to the list of results.
3974  addName(Name, nullptr);
3975 }
3976 
3978  // Compute the edit distance between the typo and this keyword,
3979  // and add the keyword to the list of results.
3980  addName(Keyword, nullptr, nullptr, true);
3981 }
3982 
3983 void TypoCorrectionConsumer::addName(StringRef Name, NamedDecl *ND,
3984  NestedNameSpecifier *NNS, bool isKeyword) {
3985  // Use a simple length-based heuristic to determine the minimum possible
3986  // edit distance. If the minimum isn't good enough, bail out early.
3987  StringRef TypoStr = Typo->getName();
3988  unsigned MinED = abs((int)Name.size() - (int)TypoStr.size());
3989  if (MinED && TypoStr.size() / MinED < 3)
3990  return;
3991 
3992  // Compute an upper bound on the allowable edit distance, so that the
3993  // edit-distance algorithm can short-circuit.
3994  unsigned UpperBound = (TypoStr.size() + 2) / 3;
3995  unsigned ED = TypoStr.edit_distance(Name, true, UpperBound);
3996  if (ED > UpperBound) return;
3997 
3998  TypoCorrection TC(&SemaRef.Context.Idents.get(Name), ND, NNS, ED);
3999  if (isKeyword) TC.makeKeyword();
4000  TC.setCorrectionRange(nullptr, Result.getLookupNameInfo());
4001  addCorrection(TC);
4002 }
4003 
4004 static const unsigned MaxTypoDistanceResultSets = 5;
4005 
4007  StringRef TypoStr = Typo->getName();
4008  StringRef Name = Correction.getCorrectionAsIdentifierInfo()->getName();
4009 
4010  // For very short typos, ignore potential corrections that have a different
4011  // base identifier from the typo or which have a normalized edit distance
4012  // longer than the typo itself.
4013  if (TypoStr.size() < 3 &&
4014  (Name != TypoStr || Correction.getEditDistance(true) > TypoStr.size()))
4015  return;
4016 
4017  // If the correction is resolved but is not viable, ignore it.
4018  if (Correction.isResolved()) {
4019  checkCorrectionVisibility(SemaRef, Correction);
4020  if (!Correction || !isCandidateViable(*CorrectionValidator, Correction))
4021  return;
4022  }
4023 
4024  TypoResultList &CList =
4025  CorrectionResults[Correction.getEditDistance(false)][Name];
4026 
4027  if (!CList.empty() && !CList.back().isResolved())
4028  CList.pop_back();
4029  if (NamedDecl *NewND = Correction.getCorrectionDecl()) {
4030  std::string CorrectionStr = Correction.getAsString(SemaRef.getLangOpts());
4031  for (TypoResultList::iterator RI = CList.begin(), RIEnd = CList.end();
4032  RI != RIEnd; ++RI) {
4033  // If the Correction refers to a decl already in the result list,
4034  // replace the existing result if the string representation of Correction
4035  // comes before the current result alphabetically, then stop as there is
4036  // nothing more to be done to add Correction to the candidate set.
4037  if (RI->getCorrectionDecl() == NewND) {
4038  if (CorrectionStr < RI->getAsString(SemaRef.getLangOpts()))
4039  *RI = Correction;
4040  return;
4041  }
4042  }
4043  }
4044  if (CList.empty() || Correction.isResolved())
4045  CList.push_back(Correction);
4046 
4047  while (CorrectionResults.size() > MaxTypoDistanceResultSets)
4048  CorrectionResults.erase(std::prev(CorrectionResults.end()));
4049 }
4050 
4052  const llvm::MapVector<NamespaceDecl *, bool> &KnownNamespaces) {
4053  SearchNamespaces = true;
4054 
4055  for (auto KNPair : KnownNamespaces)
4056  Namespaces.addNameSpecifier(KNPair.first);
4057 
4058  bool SSIsTemplate = false;
4059  if (NestedNameSpecifier *NNS =
4060  (SS && SS->isValid()) ? SS->getScopeRep() : nullptr) {
4061  if (const Type *T = NNS->getAsType())
4062  SSIsTemplate = T->getTypeClass() == Type::TemplateSpecialization;
4063  }
4064  // Do not transform this into an iterator-based loop. The loop body can
4065  // trigger the creation of further types (through lazy deserialization) and
4066  // invalide iterators into this list.
4067  auto &Types = SemaRef.getASTContext().getTypes();
4068  for (unsigned I = 0; I != Types.size(); ++I) {
4069  const auto *TI = Types[I];
4070  if (CXXRecordDecl *CD = TI->getAsCXXRecordDecl()) {
4071  CD = CD->getCanonicalDecl();
4072  if (!CD->isDependentType() && !CD->isAnonymousStructOrUnion() &&
4073  !CD->isUnion() && CD->getIdentifier() &&
4074  (SSIsTemplate || !isa<ClassTemplateSpecializationDecl>(CD)) &&
4075  (CD->isBeingDefined() || CD->isCompleteDefinition()))
4076  Namespaces.addNameSpecifier(CD);
4077  }
4078  }
4079 }
4080 
4082  if (++CurrentTCIndex < ValidatedCorrections.size())
4083  return ValidatedCorrections[CurrentTCIndex];
4084 
4085  CurrentTCIndex = ValidatedCorrections.size();
4086  while (!CorrectionResults.empty()) {
4087  auto DI = CorrectionResults.begin();
4088  if (DI->second.empty()) {
4089  CorrectionResults.erase(DI);
4090  continue;
4091  }
4092 
4093  auto RI = DI->second.begin();
4094  if (RI->second.empty()) {
4095  DI->second.erase(RI);
4096  performQualifiedLookups();
4097  continue;
4098  }
4099 
4100  TypoCorrection TC = RI->second.pop_back_val();
4101  if (TC.isResolved() || TC.requiresImport() || resolveCorrection(TC)) {
4102  ValidatedCorrections.push_back(TC);
4103  return ValidatedCorrections[CurrentTCIndex];
4104  }
4105  }
4106  return ValidatedCorrections[0]; // The empty correction.
4107 }
4108 
4109 bool TypoCorrectionConsumer::resolveCorrection(TypoCorrection &Candidate) {
4110  IdentifierInfo *Name = Candidate.getCorrectionAsIdentifierInfo();
4111  DeclContext *TempMemberContext = MemberContext;
4112  CXXScopeSpec *TempSS = SS.get();
4113 retry_lookup:
4114  LookupPotentialTypoResult(SemaRef, Result, Name, S, TempSS, TempMemberContext,
4115  EnteringContext,
4116  CorrectionValidator->IsObjCIvarLookup,
4117  Name == Typo && !Candidate.WillReplaceSpecifier());
4118  switch (Result.getResultKind()) {
4122  if (TempSS) {
4123  // Immediately retry the lookup without the given CXXScopeSpec
4124  TempSS = nullptr;
4125  Candidate.WillReplaceSpecifier(true);
4126  goto retry_lookup;
4127  }
4128  if (TempMemberContext) {
4129  if (SS && !TempSS)
4130  TempSS = SS.get();
4131  TempMemberContext = nullptr;
4132  goto retry_lookup;
4133  }
4134  if (SearchNamespaces)
4135  QualifiedResults.push_back(Candidate);
4136  break;
4137 
4139  // We don't deal with ambiguities.
4140  break;
4141 
4142  case LookupResult::Found:
4144  // Store all of the Decls for overloaded symbols
4145  for (auto *TRD : Result)
4146  Candidate.addCorrectionDecl(TRD);
4147  checkCorrectionVisibility(SemaRef, Candidate);
4148  if (!isCandidateViable(*CorrectionValidator, Candidate)) {
4149  if (SearchNamespaces)
4150  QualifiedResults.push_back(Candidate);
4151  break;
4152  }
4153  Candidate.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
4154  return true;
4155  }
4156  return false;
4157 }
4158 
4159 void TypoCorrectionConsumer::performQualifiedLookups() {
4160  unsigned TypoLen = Typo->getName().size();
4161  for (const TypoCorrection &QR : QualifiedResults) {
4162  for (const auto &NSI : Namespaces) {
4163  DeclContext *Ctx = NSI.DeclCtx;
4164  const Type *NSType = NSI.NameSpecifier->getAsType();
4165 
4166  // If the current NestedNameSpecifier refers to a class and the
4167  // current correction candidate is the name of that class, then skip
4168  // it as it is unlikely a qualified version of the class' constructor
4169  // is an appropriate correction.
4170  if (CXXRecordDecl *NSDecl = NSType ? NSType->getAsCXXRecordDecl() :
4171  nullptr) {
4172  if (NSDecl->getIdentifier() == QR.getCorrectionAsIdentifierInfo())
4173  continue;
4174  }
4175 
4176  TypoCorrection TC(QR);
4177  TC.ClearCorrectionDecls();
4178  TC.setCorrectionSpecifier(NSI.NameSpecifier);
4179  TC.setQualifierDistance(NSI.EditDistance);
4180  TC.setCallbackDistance(0); // Reset the callback distance
4181 
4182  // If the current correction candidate and namespace combination are
4183  // too far away from the original typo based on the normalized edit
4184  // distance, then skip performing a qualified name lookup.
4185  unsigned TmpED = TC.getEditDistance(true);
4186  if (QR.getCorrectionAsIdentifierInfo() != Typo && TmpED &&
4187  TypoLen / TmpED < 3)
4188  continue;
4189 
4190  Result.clear();
4191  Result.setLookupName(QR.getCorrectionAsIdentifierInfo());
4192  if (!SemaRef.LookupQualifiedName(Result, Ctx))
4193  continue;
4194 
4195  // Any corrections added below will be validated in subsequent
4196  // iterations of the main while() loop over the Consumer's contents.
4197  switch (Result.getResultKind()) {
4198  case LookupResult::Found:
4200  if (SS && SS->isValid()) {
4201  std::string NewQualified = TC.getAsString(SemaRef.getLangOpts());
4202  std::string OldQualified;
4203  llvm::raw_string_ostream OldOStream(OldQualified);
4204  SS->getScopeRep()->print(OldOStream, SemaRef.getPrintingPolicy());
4205  OldOStream << Typo->getName();
4206  // If correction candidate would be an identical written qualified
4207  // identifer, then the existing CXXScopeSpec probably included a
4208  // typedef that didn't get accounted for properly.
4209  if (OldOStream.str() == NewQualified)
4210  break;
4211  }
4212  for (LookupResult::iterator TRD = Result.begin(), TRDEnd = Result.end();
4213  TRD != TRDEnd; ++TRD) {
4214  if (SemaRef.CheckMemberAccess(TC.getCorrectionRange().getBegin(),
4215  NSType ? NSType->getAsCXXRecordDecl()
4216  : nullptr,
4217  TRD.getPair()) == Sema::AR_accessible)
4218  TC.addCorrectionDecl(*TRD);
4219  }
4220  if (TC.isResolved()) {
4221  TC.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
4222  addCorrection(TC);
4223  }
4224  break;
4225  }
4230  break;
4231  }
4232  }
4233  }
4234  QualifiedResults.clear();
4235 }
4236 
4237 TypoCorrectionConsumer::NamespaceSpecifierSet::NamespaceSpecifierSet(
4238  ASTContext &Context, DeclContext *CurContext, CXXScopeSpec *CurScopeSpec)
4239  : Context(Context), CurContextChain(buildContextChain(CurContext)) {
4240  if (NestedNameSpecifier *NNS =
4241  CurScopeSpec ? CurScopeSpec->getScopeRep() : nullptr) {
4242  llvm::raw_string_ostream SpecifierOStream(CurNameSpecifier);
4243  NNS->print(SpecifierOStream, Context.getPrintingPolicy());
4244 
4245  getNestedNameSpecifierIdentifiers(NNS, CurNameSpecifierIdentifiers);
4246  }
4247  // Build the list of identifiers that would be used for an absolute
4248  // (from the global context) NestedNameSpecifier referring to the current
4249  // context.
4250  for (DeclContext *C : llvm::reverse(CurContextChain)) {
4251  if (auto *ND = dyn_cast_or_null<NamespaceDecl>(C))
4252  CurContextIdentifiers.push_back(ND->getIdentifier());
4253  }
4254 
4255  // Add the global context as a NestedNameSpecifier
4256  SpecifierInfo SI = {cast<DeclContext>(Context.getTranslationUnitDecl()),
4258  DistanceMap[1].push_back(SI);
4259 }
4260 
4261 auto TypoCorrectionConsumer::NamespaceSpecifierSet::buildContextChain(
4262  DeclContext *Start) -> DeclContextList {
4263  assert(Start && "Building a context chain from a null context");
4264  DeclContextList Chain;
4265  for (DeclContext *DC = Start->getPrimaryContext(); DC != nullptr;
4266  DC = DC->getLookupParent()) {
4267  NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(DC);
4268  if (!DC->isInlineNamespace() && !DC->isTransparentContext() &&
4269  !(ND && ND->isAnonymousNamespace()))
4270  Chain.push_back(DC->getPrimaryContext());
4271  }
4272  return Chain;
4273 }
4274 
4275 unsigned
4276 TypoCorrectionConsumer::NamespaceSpecifierSet::buildNestedNameSpecifier(
4277  DeclContextList &DeclChain, NestedNameSpecifier *&NNS) {
4278  unsigned NumSpecifiers = 0;
4279  for (DeclContext *C : llvm::reverse(DeclChain)) {
4280  if (auto *ND = dyn_cast_or_null<NamespaceDecl>(C)) {
4281  NNS = NestedNameSpecifier::Create(Context, NNS, ND);
4282  ++NumSpecifiers;
4283  } else if (auto *RD = dyn_cast_or_null<RecordDecl>(C)) {
4284  NNS = NestedNameSpecifier::Create(Context, NNS, RD->isTemplateDecl(),
4285  RD->getTypeForDecl());
4286  ++NumSpecifiers;
4287  }
4288  }
4289  return NumSpecifiers;
4290 }
4291 
4292 void TypoCorrectionConsumer::NamespaceSpecifierSet::addNameSpecifier(
4293  DeclContext *Ctx) {
4294  NestedNameSpecifier *NNS = nullptr;
4295  unsigned NumSpecifiers = 0;
4296  DeclContextList NamespaceDeclChain(buildContextChain(Ctx));
4297  DeclContextList FullNamespaceDeclChain(NamespaceDeclChain);
4298 
4299  // Eliminate common elements from the two DeclContext chains.
4300  for (DeclContext *C : llvm::reverse(CurContextChain)) {
4301  if (NamespaceDeclChain.empty() || NamespaceDeclChain.back() != C)
4302  break;
4303  NamespaceDeclChain.pop_back();
4304  }
4305 
4306  // Build the NestedNameSpecifier from what is left of the NamespaceDeclChain
4307  NumSpecifiers = buildNestedNameSpecifier(NamespaceDeclChain, NNS);
4308 
4309  // Add an explicit leading '::' specifier if needed.
4310  if (NamespaceDeclChain.empty()) {
4311  // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
4312  NNS = NestedNameSpecifier::GlobalSpecifier(Context);
4313  NumSpecifiers =
4314  buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
4315  } else if (NamedDecl *ND =
4316  dyn_cast_or_null<NamedDecl>(NamespaceDeclChain.back())) {
4317  IdentifierInfo *Name = ND->getIdentifier();
4318  bool SameNameSpecifier = false;
4319  if (std::find(CurNameSpecifierIdentifiers.begin(),
4320  CurNameSpecifierIdentifiers.end(),
4321  Name) != CurNameSpecifierIdentifiers.end()) {
4322  std::string NewNameSpecifier;
4323  llvm::raw_string_ostream SpecifierOStream(NewNameSpecifier);
4324  SmallVector<const IdentifierInfo *, 4> NewNameSpecifierIdentifiers;
4325  getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
4326  NNS->print(SpecifierOStream, Context.getPrintingPolicy());
4327  SpecifierOStream.flush();
4328  SameNameSpecifier = NewNameSpecifier == CurNameSpecifier;
4329  }
4330  if (SameNameSpecifier ||
4331  std::find(CurContextIdentifiers.begin(), CurContextIdentifiers.end(),
4332  Name) != CurContextIdentifiers.end()) {
4333  // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
4334  NNS = NestedNameSpecifier::GlobalSpecifier(Context);
4335  NumSpecifiers =
4336  buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
4337  }
4338  }
4339 
4340  // If the built NestedNameSpecifier would be replacing an existing
4341  // NestedNameSpecifier, use the number of component identifiers that
4342  // would need to be changed as the edit distance instead of the number
4343  // of components in the built NestedNameSpecifier.
4344  if (NNS && !CurNameSpecifierIdentifiers.empty()) {
4345  SmallVector<const IdentifierInfo*, 4> NewNameSpecifierIdentifiers;
4346  getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
4347  NumSpecifiers = llvm::ComputeEditDistance(
4348  llvm::makeArrayRef(CurNameSpecifierIdentifiers),
4349  llvm::makeArrayRef(NewNameSpecifierIdentifiers));
4350  }
4351 
4352  SpecifierInfo SI = {Ctx, NNS, NumSpecifiers};
4353  DistanceMap[NumSpecifiers].push_back(SI);
4354 }
4355 
4356 /// Perform name lookup for a possible result for typo correction.
4357 static void LookupPotentialTypoResult(Sema &SemaRef,
4358  LookupResult &Res,
4359  IdentifierInfo *Name,
4360  Scope *S, CXXScopeSpec *SS,
4361  DeclContext *MemberContext,
4362  bool EnteringContext,
4363  bool isObjCIvarLookup,
4364  bool FindHidden) {
4365  Res.suppressDiagnostics();
4366  Res.clear();
4367  Res.setLookupName(Name);
4368  Res.setAllowHidden(FindHidden);
4369  if (MemberContext) {
4370  if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(MemberContext)) {
4371  if (isObjCIvarLookup) {
4372  if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(Name)) {
4373  Res.addDecl(Ivar);
4374  Res.resolveKind();
4375  return;
4376  }
4377  }
4378 
4379  if (ObjCPropertyDecl *Prop = Class->FindPropertyDeclaration(
4381  Res.addDecl(Prop);
4382  Res.resolveKind();
4383  return;
4384  }
4385  }
4386 
4387  SemaRef.LookupQualifiedName(Res, MemberContext);
4388  return;
4389  }
4390 
4391  SemaRef.LookupParsedName(Res, S, SS, /*AllowBuiltinCreation=*/false,
4392  EnteringContext);
4393 
4394  // Fake ivar lookup; this should really be part of
4395  // LookupParsedName.
4396  if (ObjCMethodDecl *Method = SemaRef.getCurMethodDecl()) {
4397  if (Method->isInstanceMethod() && Method->getClassInterface() &&
4398  (Res.empty() ||
4399  (Res.isSingleResult() &&
4401  if (ObjCIvarDecl *IV
4402  = Method->getClassInterface()->lookupInstanceVariable(Name)) {
4403  Res.addDecl(IV);
4404  Res.resolveKind();
4405  }
4406  }
4407  }
4408 }
4409 
4410 /// Add keywords to the consumer as possible typo corrections.
4411 static void AddKeywordsToConsumer(Sema &SemaRef,
4412  TypoCorrectionConsumer &Consumer,
4414  bool AfterNestedNameSpecifier) {
4415  if (AfterNestedNameSpecifier) {
4416  // For 'X::', we know exactly which keywords can appear next.
4417  Consumer.addKeywordResult("template");
4418  if (CCC.WantExpressionKeywords)
4419  Consumer.addKeywordResult("operator");
4420  return;
4421  }
4422 
4423  if (CCC.WantObjCSuper)
4424  Consumer.addKeywordResult("super");
4425 
4426  if (CCC.WantTypeSpecifiers) {
4427  // Add type-specifier keywords to the set of results.
4428  static const char *const CTypeSpecs[] = {
4429  "char", "const", "double", "enum", "float", "int", "long", "short",
4430  "signed", "struct", "union", "unsigned", "void", "volatile",
4431  "_Complex", "_Imaginary",
4432  // storage-specifiers as well
4433  "extern", "inline", "static", "typedef"
4434  };
4435 
4436  const unsigned NumCTypeSpecs = llvm::array_lengthof(CTypeSpecs);
4437  for (unsigned I = 0; I != NumCTypeSpecs; ++I)
4438  Consumer.addKeywordResult(CTypeSpecs[I]);
4439 
4440  if (SemaRef.getLangOpts().C99)
4441  Consumer.addKeywordResult("restrict");
4442  if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus)
4443  Consumer.addKeywordResult("bool");
4444  else if (SemaRef.getLangOpts().C99)
4445  Consumer.addKeywordResult("_Bool");
4446 
4447  if (SemaRef.getLangOpts().CPlusPlus) {
4448  Consumer.addKeywordResult("class");
4449  Consumer.addKeywordResult("typename");
4450  Consumer.addKeywordResult("wchar_t");
4451 
4452  if (SemaRef.getLangOpts().CPlusPlus11) {
4453  Consumer.addKeywordResult("char16_t");
4454  Consumer.addKeywordResult("char32_t");
4455  Consumer.addKeywordResult("constexpr");
4456  Consumer.addKeywordResult("decltype");
4457  Consumer.addKeywordResult("thread_local");
4458  }
4459  }
4460 
4461  if (SemaRef.getLangOpts().GNUKeywords)
4462  Consumer.addKeywordResult("typeof");
4463  } else if (CCC.WantFunctionLikeCasts) {
4464  static const char *const CastableTypeSpecs[] = {
4465  "char", "double", "float", "int", "long", "short",
4466  "signed", "unsigned", "void"
4467  };
4468  for (auto *kw : CastableTypeSpecs)
4469  Consumer.addKeywordResult(kw);
4470  }
4471 
4472  if (CCC.WantCXXNamedCasts && SemaRef.getLangOpts().CPlusPlus) {
4473  Consumer.addKeywordResult("const_cast");
4474  Consumer.addKeywordResult("dynamic_cast");
4475  Consumer.addKeywordResult("reinterpret_cast");
4476  Consumer.addKeywordResult("static_cast");
4477  }
4478 
4479  if (CCC.WantExpressionKeywords) {
4480  Consumer.addKeywordResult("sizeof");
4481  if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus) {
4482  Consumer.addKeywordResult("false");
4483  Consumer.addKeywordResult("true");
4484  }
4485 
4486  if (SemaRef.getLangOpts().CPlusPlus) {
4487  static const char *const CXXExprs[] = {
4488  "delete", "new", "operator", "throw", "typeid"
4489  };
4490  const unsigned NumCXXExprs = llvm::array_lengthof(CXXExprs);
4491  for (unsigned I = 0; I != NumCXXExprs; ++I)
4492  Consumer.addKeywordResult(CXXExprs[I]);
4493 
4494  if (isa<CXXMethodDecl>(SemaRef.CurContext) &&
4495  cast<CXXMethodDecl>(SemaRef.CurContext)->isInstance())
4496  Consumer.addKeywordResult("this");
4497 
4498  if (SemaRef.getLangOpts().CPlusPlus11) {
4499  Consumer.addKeywordResult("alignof");
4500  Consumer.addKeywordResult("nullptr");
4501  }
4502  }
4503 
4504  if (SemaRef.getLangOpts().C11) {
4505  // FIXME: We should not suggest _Alignof if the alignof macro
4506  // is present.
4507  Consumer.addKeywordResult("_Alignof");
4508  }
4509  }
4510 
4511  if (CCC.WantRemainingKeywords) {
4512  if (SemaRef.getCurFunctionOrMethodDecl() || SemaRef.getCurBlock()) {
4513  // Statements.
4514  static const char *const CStmts[] = {
4515  "do", "else", "for", "goto", "if", "return", "switch", "while" };
4516  const unsigned NumCStmts = llvm::array_lengthof(CStmts);
4517  for (unsigned I = 0; I != NumCStmts; ++I)
4518  Consumer.addKeywordResult(CStmts[I]);
4519 
4520  if (SemaRef.getLangOpts().CPlusPlus) {
4521  Consumer.addKeywordResult("catch");
4522  Consumer.addKeywordResult("try");
4523  }
4524 
4525  if (S && S->getBreakParent())
4526  Consumer.addKeywordResult("break");
4527 
4528  if (S && S->getContinueParent())
4529  Consumer.addKeywordResult("continue");
4530 
4531  if (SemaRef.getCurFunction() &&
4532  !SemaRef.getCurFunction()->SwitchStack.empty()) {
4533  Consumer.addKeywordResult("case");
4534  Consumer.addKeywordResult("default");
4535  }
4536  } else {
4537  if (SemaRef.getLangOpts().CPlusPlus) {
4538  Consumer.addKeywordResult("namespace");
4539  Consumer.addKeywordResult("template");
4540  }
4541 
4542  if (S && S->isClassScope()) {
4543  Consumer.addKeywordResult("explicit");
4544  Consumer.addKeywordResult("friend");
4545  Consumer.addKeywordResult("mutable");
4546  Consumer.addKeywordResult("private");
4547  Consumer.addKeywordResult("protected");
4548  Consumer.addKeywordResult("public");
4549  Consumer.addKeywordResult("virtual");
4550  }
4551  }
4552 
4553  if (SemaRef.getLangOpts().CPlusPlus) {
4554  Consumer.addKeywordResult("using");
4555 
4556  if (SemaRef.getLangOpts().CPlusPlus11)
4557  Consumer.addKeywordResult("static_assert");
4558  }
4559  }
4560 }
4561 
4562 std::unique_ptr<TypoCorrectionConsumer> Sema::makeTypoCorrectionConsumer(
4563  const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
4564  Scope *S, CXXScopeSpec *SS,
4565  std::unique_ptr<CorrectionCandidateCallback> CCC,
4566  DeclContext *MemberContext, bool EnteringContext,
4567  const ObjCObjectPointerType *OPT, bool ErrorRecovery) {
4568 
4569  if (Diags.hasFatalErrorOccurred() || !getLangOpts().SpellChecking ||
4570  DisableTypoCorrection)
4571  return nullptr;
4572 
4573  // In Microsoft mode, don't perform typo correction in a template member
4574  // function dependent context because it interferes with the "lookup into
4575  // dependent bases of class templates" feature.
4576  if (getLangOpts().MSVCCompat && CurContext->isDependentContext() &&
4577  isa<CXXMethodDecl>(CurContext))
4578  return nullptr;
4579 
4580  // We only attempt to correct typos for identifiers.
4581  IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4582  if (!Typo)
4583  return nullptr;
4584 
4585  // If the scope specifier itself was invalid, don't try to correct
4586  // typos.
4587  if (SS && SS->isInvalid())
4588  return nullptr;
4589 
4590  // Never try to correct typos during any kind of code synthesis.
4591  if (!CodeSynthesisContexts.empty())
4592  return nullptr;
4593 
4594  // Don't try to correct 'super'.
4595  if (S && S->isInObjcMethodScope() && Typo == getSuperIdentifier())
4596  return nullptr;
4597 
4598  // Abort if typo correction already failed for this specific typo.
4599  IdentifierSourceLocations::iterator locs = TypoCorrectionFailures.find(Typo);
4600  if (locs != TypoCorrectionFailures.end() &&
4601  locs->second.count(TypoName.getLoc()))
4602  return nullptr;
4603 
4604  // Don't try to correct the identifier "vector" when in AltiVec mode.
4605  // TODO: Figure out why typo correction misbehaves in this case, fix it, and
4606  // remove this workaround.
4607  if ((getLangOpts().AltiVec || getLangOpts().ZVector) && Typo->isStr("vector"))
4608  return nullptr;
4609 
4610  // Provide a stop gap for files that are just seriously broken. Trying
4611  // to correct all typos can turn into a HUGE performance penalty, causing
4612  // some files to take minutes to get rejected by the parser.
4613  unsigned Limit = getDiagnostics().getDiagnosticOptions().SpellCheckingLimit;
4614  if (Limit && TyposCorrected >= Limit)
4615  return nullptr;
4616  ++TyposCorrected;
4617 
4618  // If we're handling a missing symbol error, using modules, and the
4619  // special search all modules option is used, look for a missing import.
4620  if (ErrorRecovery && getLangOpts().Modules &&
4621  getLangOpts().ModulesSearchAll) {
4622  // The following has the side effect of loading the missing module.
4623  getModuleLoader().lookupMissingImports(Typo->getName(),
4624  TypoName.getBeginLoc());
4625  }
4626 
4627  CorrectionCandidateCallback &CCCRef = *CCC;
4628  auto Consumer = llvm::make_unique<TypoCorrectionConsumer>(
4629  *this, TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4630  EnteringContext);
4631 
4632  // Perform name lookup to find visible, similarly-named entities.
4633  bool IsUnqualifiedLookup = false;
4634  DeclContext *QualifiedDC = MemberContext;
4635  if (MemberContext) {
4636  LookupVisibleDecls(MemberContext, LookupKind, *Consumer);
4637 
4638  // Look in qualified interfaces.
4639  if (OPT) {
4640  for (auto *I : OPT->quals())
4641  LookupVisibleDecls(I, LookupKind, *Consumer);
4642  }
4643  } else if (SS && SS->isSet()) {
4644  QualifiedDC = computeDeclContext(*SS, EnteringContext);
4645  if (!QualifiedDC)
4646  return nullptr;
4647 
4648  LookupVisibleDecls(QualifiedDC, LookupKind, *Consumer);
4649  } else {
4650  IsUnqualifiedLookup = true;
4651  }
4652 
4653  // Determine whether we are going to search in the various namespaces for
4654  // corrections.
4655  bool SearchNamespaces
4656  = getLangOpts().CPlusPlus &&
4657  (IsUnqualifiedLookup || (SS && SS->isSet()));
4658 
4659  if (IsUnqualifiedLookup || SearchNamespaces) {
4660  // For unqualified lookup, look through all of the names that we have
4661  // seen in this translation unit.
4662  // FIXME: Re-add the ability to skip very unlikely potential corrections.
4663  for (const auto &I : Context.Idents)
4664  Consumer->FoundName(I.getKey());
4665 
4666  // Walk through identifiers in external identifier sources.
4667  // FIXME: Re-add the ability to skip very unlikely potential corrections.
4668  if (IdentifierInfoLookup *External
4669  = Context.Idents.getExternalIdentifierLookup()) {
4670  std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
4671  do {
4672  StringRef Name = Iter->Next();
4673  if (Name.empty())
4674  break;
4675 
4676  Consumer->FoundName(Name);
4677  } while (true);
4678  }
4679  }
4680 
4681  AddKeywordsToConsumer(*this, *Consumer, S, CCCRef, SS && SS->isNotEmpty());
4682 
4683  // Build the NestedNameSpecifiers for the KnownNamespaces, if we're going
4684  // to search those namespaces.
4685  if (SearchNamespaces) {
4686  // Load any externally-known namespaces.
4687  if (ExternalSource && !LoadedExternalKnownNamespaces) {
4688  SmallVector<NamespaceDecl *, 4> ExternalKnownNamespaces;
4689  LoadedExternalKnownNamespaces = true;
4690  ExternalSource->ReadKnownNamespaces(ExternalKnownNamespaces);
4691  for (auto *N : ExternalKnownNamespaces)
4692  KnownNamespaces[N] = true;
4693  }
4694 
4695  Consumer->addNamespaces(KnownNamespaces);
4696  }
4697 
4698  return Consumer;
4699 }
4700 
4701 /// Try to "correct" a typo in the source code by finding
4702 /// visible declarations whose names are similar to the name that was
4703 /// present in the source code.
4704 ///
4705 /// \param TypoName the \c DeclarationNameInfo structure that contains
4706 /// the name that was present in the source code along with its location.
4707 ///
4708 /// \param LookupKind the name-lookup criteria used to search for the name.
4709 ///
4710 /// \param S the scope in which name lookup occurs.
4711 ///
4712 /// \param SS the nested-name-specifier that precedes the name we're
4713 /// looking for, if present.
4714 ///
4715 /// \param CCC A CorrectionCandidateCallback object that provides further
4716 /// validation of typo correction candidates. It also provides flags for
4717 /// determining the set of keywords permitted.
4718 ///
4719 /// \param MemberContext if non-NULL, the context in which to look for
4720 /// a member access expression.
4721 ///
4722 /// \param EnteringContext whether we're entering the context described by
4723 /// the nested-name-specifier SS.
4724 ///
4725 /// \param OPT when non-NULL, the search for visible declarations will
4726 /// also walk the protocols in the qualified interfaces of \p OPT.
4727 ///
4728 /// \returns a \c TypoCorrection containing the corrected name if the typo
4729 /// along with information such as the \c NamedDecl where the corrected name
4730 /// was declared, and any additional \c NestedNameSpecifier needed to access
4731 /// it (C++ only). The \c TypoCorrection is empty if there is no correction.
4733  Sema::LookupNameKind LookupKind,
4734  Scope *S, CXXScopeSpec *SS,
4735  std::unique_ptr<CorrectionCandidateCallback> CCC,
4736  CorrectTypoKind Mode,
4737  DeclContext *MemberContext,
4738  bool EnteringContext,
4739  const ObjCObjectPointerType *OPT,
4740  bool RecordFailure) {
4741  assert(CCC && "CorrectTypo requires a CorrectionCandidateCallback");
4742 
4743  // Always let the ExternalSource have the first chance at correction, even
4744  // if we would otherwise have given up.
4745  if (ExternalSource) {
4746  if (TypoCorrection Correction = ExternalSource->CorrectTypo(
4747  TypoName, LookupKind, S, SS, *CCC, MemberContext, EnteringContext, OPT))
4748  return Correction;
4749  }
4750 
4751  // Ugly hack equivalent to CTC == CTC_ObjCMessageReceiver;
4752  // WantObjCSuper is only true for CTC_ObjCMessageReceiver and for
4753  // some instances of CTC_Unknown, while WantRemainingKeywords is true
4754  // for CTC_Unknown but not for CTC_ObjCMessageReceiver.
4755  bool ObjCMessageReceiver = CCC->WantObjCSuper && !CCC->WantRemainingKeywords;
4756 
4757  IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4758  auto Consumer = makeTypoCorrectionConsumer(
4759  TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4760  EnteringContext, OPT, Mode == CTK_ErrorRecovery);
4761 
4762  if (!Consumer)
4763  return TypoCorrection();
4764 
4765  // If we haven't found anything, we're done.
4766  if (Consumer->empty())
4767  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4768 
4769  // Make sure the best edit distance (prior to adding any namespace qualifiers)
4770  // is not more that about a third of the length of the typo's identifier.
4771  unsigned ED = Consumer->getBestEditDistance(true);
4772  unsigned TypoLen = Typo->getName().size();
4773  if (ED > 0 && TypoLen / ED < 3)
4774  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4775 
4776  TypoCorrection BestTC = Consumer->getNextCorrection();
4777  TypoCorrection SecondBestTC = Consumer->getNextCorrection();
4778  if (!BestTC)
4779  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4780 
4781  ED = BestTC.getEditDistance();
4782 
4783  if (TypoLen >= 3 && ED > 0 && TypoLen / ED < 3) {
4784  // If this was an unqualified lookup and we believe the callback
4785  // object wouldn't have filtered out possible corrections, note
4786  // that no correction was found.
4787  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4788  }
4789 
4790  // If only a single name remains, return that result.
4791  if (!SecondBestTC ||
4792  SecondBestTC.getEditDistance(false) > BestTC.getEditDistance(false)) {
4793  const TypoCorrection &Result = BestTC;
4794 
4795  // Don't correct to a keyword that's the same as the typo; the keyword
4796  // wasn't actually in scope.
4797  if (ED == 0 && Result.isKeyword())
4798  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4799 
4800  TypoCorrection TC = Result;
4801  TC.setCorrectionRange(SS, TypoName);
4802  checkCorrectionVisibility(*this, TC);
4803  return TC;
4804  } else if (SecondBestTC && ObjCMessageReceiver) {
4805  // Prefer 'super' when we're completing in a message-receiver
4806  // context.
4807 
4808  if (BestTC.getCorrection().getAsString() != "super") {
4809  if (SecondBestTC.getCorrection().getAsString() == "super")
4810  BestTC = SecondBestTC;
4811  else if ((*Consumer)["super"].front().isKeyword())
4812  BestTC = (*Consumer)["super"].front();
4813  }
4814  // Don't correct to a keyword that's the same as the typo; the keyword
4815  // wasn't actually in scope.
4816  if (BestTC.getEditDistance() == 0 ||
4817  BestTC.getCorrection().getAsString() != "super")
4818  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
4819 
4820  BestTC.setCorrectionRange(SS, TypoName);
4821  return BestTC;
4822  }
4823 
4824  // Record the failure's location if needed and return an empty correction. If
4825  // this was an unqualified lookup and we believe the callback object did not
4826  // filter out possible corrections, also cache the failure for the typo.
4827  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure && !SecondBestTC);
4828 }
4829 
4830 /// Try to "correct" a typo in the source code by finding
4831 /// visible declarations whose names are similar to the name that was
4832 /// present in the source code.
4833 ///
4834 /// \param TypoName the \c DeclarationNameInfo structure that contains
4835 /// the name that was present in the source code along with its location.
4836 ///
4837 /// \param LookupKind the name-lookup criteria used to search for the name.
4838 ///
4839 /// \param S the scope in which name lookup occurs.
4840 ///
4841 /// \param SS the nested-name-specifier that precedes the name we're
4842 /// looking for, if present.
4843 ///
4844 /// \param CCC A CorrectionCandidateCallback object that provides further
4845 /// validation of typo correction candidates. It also provides flags for
4846 /// determining the set of keywords permitted.
4847 ///
4848 /// \param TDG A TypoDiagnosticGenerator functor that will be used to print
4849 /// diagnostics when the actual typo correction is attempted.
4850 ///
4851 /// \param TRC A TypoRecoveryCallback functor that will be used to build an
4852 /// Expr from a typo correction candidate.
4853 ///
4854 /// \param MemberContext if non-NULL, the context in which to look for
4855 /// a member access expression.
4856 ///
4857 /// \param EnteringContext whether we're entering the context described by
4858 /// the nested-name-specifier SS.
4859 ///
4860 /// \param OPT when non-NULL, the search for visible declarations will
4861 /// also walk the protocols in the qualified interfaces of \p OPT.
4862 ///
4863 /// \returns a new \c TypoExpr that will later be replaced in the AST with an
4864 /// Expr representing the result of performing typo correction, or nullptr if
4865 /// typo correction is not possible. If nullptr is returned, no diagnostics will
4866 /// be emitted and it is the responsibility of the caller to emit any that are
4867 /// needed.
4869  const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
4870  Scope *S, CXXScopeSpec *SS,
4871  std::unique_ptr<CorrectionCandidateCallback> CCC,
4873  DeclContext *MemberContext, bool EnteringContext,
4874  const ObjCObjectPointerType *OPT) {
4875  assert(CCC && "CorrectTypoDelayed requires a CorrectionCandidateCallback");
4876 
4877  auto Consumer = makeTypoCorrectionConsumer(
4878  TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
4879  EnteringContext, OPT, Mode == CTK_ErrorRecovery);
4880 
4881  // Give the external sema source a chance to correct the typo.
4882  TypoCorrection ExternalTypo;
4883  if (ExternalSource && Consumer) {
4884  ExternalTypo = ExternalSource->CorrectTypo(
4885  TypoName, LookupKind, S, SS, *Consumer->getCorrectionValidator(),
4886  MemberContext, EnteringContext, OPT);
4887  if (ExternalTypo)
4888  Consumer->addCorrection(ExternalTypo);
4889  }
4890 
4891  if (!Consumer || Consumer->empty())
4892  return nullptr;
4893 
4894  // Make sure the best edit distance (prior to adding any namespace qualifiers)
4895  // is not more that about a third of the length of the typo's identifier.
4896  unsigned ED = Consumer->getBestEditDistance(true);
4897  IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
4898  if (!ExternalTypo && ED > 0 && Typo->getName().size() / ED < 3)
4899  return nullptr;
4900 
4901  ExprEvalContexts.back().NumTypos++;
4902  return createDelayedTypo(std::move(Consumer), std::move(TDG), std::move(TRC));
4903 }
4904 
4906  if (!CDecl) return;
4907 
4908  if (isKeyword())
4909  CorrectionDecls.clear();
4910 
4911  CorrectionDecls.push_back(CDecl);
4912 
4913  if (!CorrectionName)
4914  CorrectionName = CDecl->getDeclName();
4915 }
4916 
4917 std::string TypoCorrection::getAsString(const LangOptions &LO) const {
4918  if (CorrectionNameSpec) {
4919  std::string tmpBuffer;
4920  llvm::raw_string_ostream PrefixOStream(tmpBuffer);
4921  CorrectionNameSpec->print(PrefixOStream, PrintingPolicy(LO));
4922  PrefixOStream << CorrectionName;
4923  return PrefixOStream.str();
4924  }
4925 
4926  return CorrectionName.getAsString();
4927 }
4928 
4930  const TypoCorrection &candidate) {
4931  if (!candidate.isResolved())
4932  return true;
4933 
4934  if (candidate.isKeyword())
4935  return WantTypeSpecifiers || WantExpressionKeywords || WantCXXNamedCasts ||
4936  WantRemainingKeywords || WantObjCSuper;
4937 
4938  bool HasNonType = false;
4939  bool HasStaticMethod = false;
4940  bool HasNonStaticMethod = false;
4941  for (Decl *D : candidate) {
4942  if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(D))
4943  D = FTD->getTemplatedDecl();
4944  if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
4945  if (Method->isStatic())
4946  HasStaticMethod = true;
4947  else
4948  HasNonStaticMethod = true;
4949  }
4950  if (!isa<TypeDecl>(D))
4951  HasNonType = true;
4952  }
4953 
4954  if (IsAddressOfOperand && HasNonStaticMethod && !HasStaticMethod &&
4955  !candidate.getCorrectionSpecifier())
4956  return false;
4957 
4958  return WantTypeSpecifiers || HasNonType;
4959 }
4960 
4962  bool HasExplicitTemplateArgs,
4963  MemberExpr *ME)
4964  : NumArgs(NumArgs), HasExplicitTemplateArgs(HasExplicitTemplateArgs),
4965  CurContext(SemaRef.CurContext), MemberFn(ME) {
4966  WantTypeSpecifiers = false;
4967  WantFunctionLikeCasts = SemaRef.getLangOpts().CPlusPlus && NumArgs == 1;
4968  WantRemainingKeywords = false;
4969 }
4970 
4972  if (!candidate.getCorrectionDecl())
4973  return candidate.isKeyword();
4974 
4975  for (auto *C : candidate) {
4976  FunctionDecl *FD = nullptr;
4977  NamedDecl *ND = C->getUnderlyingDecl();
4978  if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
4979  FD = FTD->getTemplatedDecl();
4980  if (!HasExplicitTemplateArgs && !FD) {
4981  if (!(FD = dyn_cast<FunctionDecl>(ND)) && isa<ValueDecl>(ND)) {
4982  // If the Decl is neither a function nor a template function,
4983  // determine if it is a pointer or reference to a function. If so,
4984  // check against the number of arguments expected for the pointee.
4985  QualType ValType = cast<ValueDecl>(ND)->getType();
4986  if (ValType.isNull())
4987  continue;
4988  if (ValType->isAnyPointerType() || ValType->isReferenceType())
4989  ValType = ValType->getPointeeType();
4990  if (const FunctionProtoType *FPT = ValType->getAs<FunctionProtoType>())
4991  if (FPT->getNumParams() == NumArgs)
4992  return true;
4993  }
4994  }
4995 
4996  // Skip the current candidate if it is not a FunctionDecl or does not accept
4997  // the current number of arguments.
4998  if (!FD || !(FD->getNumParams() >= NumArgs &&
4999  FD->getMinRequiredArguments() <= NumArgs))
5000  continue;
5001 
5002  // If the current candidate is a non-static C++ method, skip the candidate
5003  // unless the method being corrected--or the current DeclContext, if the
5004  // function being corrected is not a method--is a method in the same class
5005  // or a descendent class of the candidate's parent class.
5006  if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
5007  if (MemberFn || !MD->isStatic()) {
5008  CXXMethodDecl *CurMD =
5009  MemberFn
5010  ? dyn_cast_or_null<CXXMethodDecl>(MemberFn->getMemberDecl())
5011  : dyn_cast_or_null<CXXMethodDecl>(CurContext);
5012  CXXRecordDecl *CurRD =
5013  CurMD ? CurMD->getParent()->getCanonicalDecl() : nullptr;
5014  CXXRecordDecl *RD = MD->getParent()->getCanonicalDecl();
5015  if (!CurRD || (CurRD != RD && !CurRD->isDerivedFrom(RD)))
5016  continue;
5017  }
5018  }
5019  return true;
5020  }
5021  return false;
5022 }
5023 
5024 void Sema::diagnoseTypo(const TypoCorrection &Correction,
5025  const PartialDiagnostic &TypoDiag,
5026  bool ErrorRecovery) {
5027  diagnoseTypo(Correction, TypoDiag, PDiag(diag::note_previous_decl),
5028  ErrorRecovery);
5029 }
5030 
5031 /// Find which declaration we should import to provide the definition of
5032 /// the given declaration.
5034  if (VarDecl *VD = dyn_cast<VarDecl>(D))
5035  return VD->getDefinition();
5036  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
5037  return FD->getDefinition();
5038  if (TagDecl *TD = dyn_cast<TagDecl>(D))
5039  return TD->getDefinition();
5040  if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(D))
5041  return ID->getDefinition();
5042  if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl>(D))
5043  return PD->getDefinition();
5044  if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
5045  return getDefinitionToImport(TD->getTemplatedDecl());
5046  return nullptr;
5047 }
5048 
5050  MissingImportKind MIK, bool Recover) {
5051  // Suggest importing a module providing the definition of this entity, if
5052  // possible.
5053  NamedDecl *Def = getDefinitionToImport(Decl);
5054  if (!Def)
5055  Def = Decl;
5056 
5057  Module *Owner = getOwningModule(Def);
5058  assert(Owner && "definition of hidden declaration is not in a module");
5059 
5060  llvm::SmallVector<Module*, 8> OwningModules;
5061  OwningModules.push_back(Owner);
5062  auto Merged = Context.getModulesWithMergedDefinition(Def);
5063  OwningModules.insert(OwningModules.end(), Merged.begin(), Merged.end());
5064 
5065  diagnoseMissingImport(Loc, Decl, Decl->getLocation(), OwningModules, MIK,
5066  Recover);
5067 }
5068 
5069 /// Get a "quoted.h" or <angled.h> include path to use in a diagnostic
5070 /// suggesting the addition of a #include of the specified file.
5072  const FileEntry *E) {
5073  bool IsSystem;
5074  auto Path =
5076  return (IsSystem ? '<' : '"') + Path + (IsSystem ? '>' : '"');
5077 }
5078 
5080  SourceLocation DeclLoc,
5081  ArrayRef<Module *> Modules,
5082  MissingImportKind MIK, bool Recover) {
5083  assert(!Modules.empty());
5084 
5085  // Weed out duplicates from module list.
5086  llvm::SmallVector<Module*, 8> UniqueModules;
5087  llvm::SmallDenseSet<Module*, 8> UniqueModuleSet;
5088  for (auto *M : Modules)
5089  if (UniqueModuleSet.insert(M).second)
5090  UniqueModules.push_back(M);
5091  Modules = UniqueModules;
5092 
5093  if (Modules.size() > 1) {
5094  std::string ModuleList;
5095  unsigned N = 0;
5096  for (Module *M : Modules) {
5097  ModuleList += "\n ";
5098  if (++N == 5 && N != Modules.size()) {
5099  ModuleList += "[...]";
5100  break;
5101  }
5102  ModuleList += M->getFullModuleName();
5103  }
5104 
5105  Diag(UseLoc, diag::err_module_unimported_use_multiple)
5106  << (int)MIK << Decl << ModuleList;
5107  } else if (const FileEntry *E = PP.getModuleHeaderToIncludeForDiagnostics(
5108  UseLoc, Modules[0], DeclLoc)) {
5109  // The right way to make the declaration visible is to include a header;
5110  // suggest doing so.
5111  //
5112  // FIXME: Find a smart place to suggest inserting a #include, and add
5113  // a FixItHint there.
5114  Diag(UseLoc, diag::err_module_unimported_use_header)
5115  << (int)MIK << Decl << Modules[0]->getFullModuleName()
5116  << getIncludeStringForHeader(PP, E);
5117  } else {
5118  // FIXME: Add a FixItHint that imports the corresponding module.
5119  Diag(UseLoc, diag::err_module_unimported_use)
5120  << (int)MIK << Decl << Modules[0]->getFullModuleName();
5121  }
5122 
5123  unsigned DiagID;
5124  switch (MIK) {
5125  case MissingImportKind::Declaration:
5126  DiagID = diag::note_previous_declaration;
5127  break;
5128  case MissingImportKind::Definition:
5129  DiagID = diag::note_previous_definition;
5130  break;
5131  case MissingImportKind::DefaultArgument:
5132  DiagID = diag::note_default_argument_declared_here;
5133  break;
5134  case MissingImportKind::ExplicitSpecialization:
5135  DiagID = diag::note_explicit_specialization_declared_here;
5136  break;
5137  case MissingImportKind::PartialSpecialization:
5138  DiagID = diag::note_partial_specialization_declared_here;
5139  break;
5140  }
5141  Diag(DeclLoc, DiagID);
5142 
5143  // Try to recover by implicitly importing this module.
5144  if (Recover)
5145  createImplicitModuleImportForErrorRecovery(UseLoc, Modules[0]);
5146 }
5147 
5148 /// Diagnose a successfully-corrected typo. Separated from the correction
5149 /// itself to allow external validation of the result, etc.
5150 ///
5151 /// \param Correction The result of performing typo correction.
5152 /// \param TypoDiag The diagnostic to produce. This will have the corrected
5153 /// string added to it (and usually also a fixit).
5154 /// \param PrevNote A note to use when indicating the location of the entity to
5155 /// which we are correcting. Will have the correction string added to it.
5156 /// \param ErrorRecovery If \c true (the default), the caller is going to
5157 /// recover from the typo as if the corrected string had been typed.
5158 /// In this case, \c PDiag must be an error, and we will attach a fixit
5159 /// to it.
5160 void Sema::diagnoseTypo(const TypoCorrection &Correction,
5161  const PartialDiagnostic &TypoDiag,
5162  const PartialDiagnostic &PrevNote,
5163  bool ErrorRecovery) {
5164  std::string CorrectedStr = Correction.getAsString(getLangOpts());
5165  std::string CorrectedQuotedStr = Correction.getQuoted(getLangOpts());
5167  Correction.getCorrectionRange(), CorrectedStr);
5168 
5169  // Maybe we're just missing a module import.
5170  if (Correction.requiresImport()) {
5171  NamedDecl *Decl = Correction.getFoundDecl();
5172  assert(Decl && "import required but no declaration to import");
5173 
5174  diagnoseMissingImport(Correction.getCorrectionRange().getBegin(), Decl,
5175  MissingImportKind::Declaration, ErrorRecovery);
5176  return;
5177  }
5178 
5179  Diag(Correction.getCorrectionRange().getBegin(), TypoDiag)
5180  << CorrectedQuotedStr << (ErrorRecovery ? FixTypo : FixItHint());
5181 
5182  NamedDecl *ChosenDecl =
5183  Correction.isKeyword() ? nullptr : Correction.getFoundDecl();
5184  if (PrevNote.getDiagID() && ChosenDecl)
5185  Diag(ChosenDecl->getLocation(), PrevNote)
5186  << CorrectedQuotedStr << (ErrorRecovery ? FixItHint() : FixTypo);
5187 
5188  // Add any extra diagnostics.
5189  for (const PartialDiagnostic &PD : Correction.getExtraDiagnostics())
5190  Diag(Correction.getCorrectionRange().getBegin(), PD);
5191 }
5192 
5193 TypoExpr *Sema::createDelayedTypo(std::unique_ptr<TypoCorrectionConsumer> TCC,
5195  TypoRecoveryCallback TRC) {
5196  assert(TCC && "createDelayedTypo requires a valid TypoCorrectionConsumer");
5197  auto TE = new (Context) TypoExpr(Context.DependentTy);
5198  auto &State = DelayedTypos[TE];
5199  State.Consumer = std::move(TCC);
5200  State.DiagHandler = std::move(TDG);
5201  State.RecoveryHandler = std::move(TRC);
5202  return TE;
5203 }
5204 
5205 const Sema::TypoExprState &Sema::getTypoExprState(TypoExpr *TE) const {
5206  auto Entry = DelayedTypos.find(TE);
5207  assert(Entry != DelayedTypos.end() &&
5208  "Failed to get the state for a TypoExpr!");
5209  return Entry->second;
5210 }
5211 
5213  DelayedTypos.erase(TE);
5214 }
5215 
5217  DeclarationNameInfo Name(II, IILoc);
5218  LookupResult R(*this, Name, LookupAnyName, Sema::NotForRedeclaration);
5219  R.suppressDiagnostics();
5220  R.setHideTags(false);
5221  LookupName(R, S);
5222  R.dump();
5223 }
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:1717
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:1060
no exception specification
PointerType - C99 6.7.5.1 - Pointer Declarators.
Definition: Type.h:2511
A (possibly-)qualified type.
Definition: Type.h:642
Simple class containing the result of Sema::CorrectTypo.
base_class_range bases()
Definition: DeclCXX.h:823
ValueDecl * getMemberDecl() const
Retrieve the member declaration to which this expression refers.
Definition: Expr.h:2563
bool hasVisibleDeclarationSlow(const NamedDecl *D, llvm::SmallVectorImpl< Module *> *Modules)
CorrectTypoKind
Definition: Sema.h:3242
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:6900
Ordinary name lookup, which finds ordinary names (functions, variables, typedefs, etc...
Definition: Sema.h:3026
DeclarationName getCXXConstructorName(CanQualType Ty)
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:3060
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:3329
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:497
void addConst()
Add the const type qualifier to this QualType.
Definition: Type.h:811
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:87
__DEVICE__ long long abs(long long __n)
bool isModuleVisible(const Module *M, bool ModulePrivate=false)
A reference to a name which we were able to look up during parsing but could not resolve to a specifi...
Definition: ExprCXX.h:2769
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:376
OverloadedOperatorKind getCXXOverloadedOperator() const
If this name is the name of an overloadable operator in C++ (e.g., operator+), retrieve the kind of o...
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:814
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:7241
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:959
NamedDecl * getDecl() const
The base class of the type hierarchy.
Definition: Type.h:1415
SourceLocation getBeginLoc() const
getBeginLoc - Retrieve the location of the first token.
MissingImportKind
Kinds of missing import.
Definition: Sema.h:2113
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:3071
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:3042
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:1164
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:3096
unsigned getIdentifierNamespace() const
Definition: DeclBase.h:798
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2480
bool isCompleteDefinition() const
Return true if this decl has its body fully specified.
Definition: Decl.h:3146
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:3046
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:1948
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.
DeclarationName getLookupName() const
Gets the name to look up.
Definition: Lookup.h:241
const T * getAs() const
Member-template getAs<specific type>&#39;.
Definition: Type.h:6590
PrintingPolicy getPrintingPolicy() const
Retrieve a suitable printing policy for diagnostics.
Definition: Sema.h:2146
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:3669
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:1115
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:548
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:3055
Defines the clang::Expr interface and subclasses for C++ expressions.
void addKeywordResult(StringRef Keyword)
void setMethod(CXXMethodDecl *MD)
Definition: Sema.h:1061
ModuleKind Kind
The kind of this module.
Definition: Module.h:87
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:131
Represents a struct/union/class.
Definition: Decl.h:3570
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:1127
FunctionType::ExtInfo ExtInfo
Definition: Type.h:3670
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:154
DeclarationName getCorrection() const
Gets the DeclarationName of the typo correction.
The results of name lookup within a DeclContext.
Definition: DeclBase.h:1192
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
NameKind getNameKind() const
Determine what kind of name this is.
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:153
void setVisibleDespiteOwningModule()
Set that this declaration is globally visible, even if it came from a module that is not visible...
Definition: DeclBase.h:779
const DeclarationNameInfo & getLookupNameInfo() const
Gets the name info to look up.
Definition: Lookup.h:231
conversion_iterator conversion_end() const
Definition: DeclCXX.h:1269
bool isReferenceType() const
Definition: Type.h:6189
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:854
int Category
Definition: Format.cpp:1605
bool Equals(const DeclContext *DC) const
Determine whether this declaration context is equivalent to the declaration context DC...
Definition: DeclBase.h:1878
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:565
SpecialMemberOverloadResult - The overloading result for a special member function.
Definition: Sema.h:1044
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
StringRef getTopLevelModuleName() const
Retrieve the name of the top-level module.
Definition: Module.h:461
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:3062
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:141
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:833
void setQualifierDistance(unsigned ED)
bool hasTagIdentifierNamespace() const
Definition: DeclBase.h:808
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:1559
CXXConstructorDecl * DeclareImplicitMoveConstructor(CXXRecordDecl *ClassDecl)
Declare the implicit move constructor for the given class.
Look up all declarations in a scope with the given name, including resolved using declarations...
Definition: Sema.h:3050
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:663
IdentifierInfoLookup * getExternalIdentifierLookup() const
Retrieve the external identifier lookup object, if any.
Represents a declaration of a type.
Definition: Decl.h:2851
A set of unresolved declarations.
Definition: UnresolvedSet.h:61
static unsigned getIDNS(Sema::LookupNameKind NameKind, bool CPlusPlus, bool Redeclaration)
Definition: SemaLookup.cpp:209
Module * Parent
The parent of this module.
Definition: Module.h:91
const Type * getClass() const
Definition: Type.h:2764
Look up the name of an OpenMP user-defined reduction operation.
Definition: Sema.h:3064
std::function< ExprResult(Sema &, TypoExpr *, TypoCorrection)> TypoRecoveryCallback
Definition: Sema.h:3127
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:5953
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:5359
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:830
Represents an Objective-C protocol declaration.
Definition: DeclObjC.h:2056
lookups_range lookups() const
Definition: DeclLookups.h:76
DeclContext * getLexicalDeclContext()
getLexicalDeclContext - The declaration context where this Decl was lexically declared (LexicalDC)...
Definition: DeclBase.h:827
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:1212
Labels, declared with &#39;x:&#39; and referenced with &#39;goto x&#39;.
Definition: DeclBase.h:118
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:1674
Represents an ObjC class declaration.
Definition: DeclObjC.h:1164
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:3034
Ordinary names.
Definition: DeclBase.h:145
virtual Decl * getCanonicalDecl()
Retrieves the "canonical" declaration of the given declaration.
Definition: DeclBase.h:876
lookup_result lookup(DeclarationName Name) const
lookup - Find the declarations (if any) with the given Name in this context.
Definition: DeclBase.cpp:1566
ExtInfo withCallingConv(CallingConv cc) const
Definition: Type.h:3459
static const unsigned InvalidDistance
CXXSpecialMember
Kinds of C++ special members.
Definition: Sema.h:1148
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:277
udir_range using_directives() const
Returns iterator range [First, Last) of UsingDirectiveDecls stored within this context.
Definition: DeclBase.cpp:1855
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:999
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:1605
Represents a prototype with parameter type info, e.g.
Definition: Type.h:3550
std::string CurrentModule
The name of the current module, of which the main source file is a part.
Definition: LangOptions.h:194
This declaration is a C++ operator declared in a non-class context.
Definition: DeclBase.h:169
Objective C @protocol.
Definition: DeclBase.h:148
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:301
DeclarationNameTable DeclarationNames
Definition: ASTContext.h:568
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:3125
This declaration is a friend class.
Definition: DeclBase.h:158
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:1036
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:1774
QualType getCXXNameType() const
If this name is one of the C++ names (of a constructor, destructor, or conversion function)...
NamespaceDecl * getAsNamespace() const
Retrieve the namespace stored in this nested name specifier.
This represents one expression.
Definition: Expr.h:105
Defines the clang::LangOptions interface.
LookupNameKind
Describes the kind of name lookup to perform.
Definition: Sema.h:3022
ExprValueKind
The categorization of expression values, currently following the C++11 scheme.
Definition: Specifiers.h:107
llvm::StringRef getAsString(SyncScope S)
Definition: SyncScope.h:51
bool isDeclScope(Decl *D)
isDeclScope - Return true if this is the scope that the specified decl is declared in...
Definition: Scope.h:320
int Id
Definition: ASTDiff.cpp:191
int SubobjectNumber
Identifies