clang  14.0.0git
SemaExprCXX.cpp
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1 //===--- SemaExprCXX.cpp - Semantic Analysis for Expressions --------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 ///
9 /// \file
10 /// Implements semantic analysis for C++ expressions.
11 ///
12 //===----------------------------------------------------------------------===//
13 
14 #include "clang/Sema/Template.h"
16 #include "TreeTransform.h"
17 #include "TypeLocBuilder.h"
18 #include "clang/AST/ASTContext.h"
19 #include "clang/AST/ASTLambda.h"
21 #include "clang/AST/CharUnits.h"
22 #include "clang/AST/DeclObjC.h"
23 #include "clang/AST/ExprCXX.h"
24 #include "clang/AST/ExprObjC.h"
26 #include "clang/AST/TypeLoc.h"
29 #include "clang/Basic/TargetInfo.h"
30 #include "clang/Lex/Preprocessor.h"
31 #include "clang/Sema/DeclSpec.h"
33 #include "clang/Sema/Lookup.h"
35 #include "clang/Sema/Scope.h"
36 #include "clang/Sema/ScopeInfo.h"
37 #include "clang/Sema/SemaLambda.h"
39 #include "llvm/ADT/APInt.h"
40 #include "llvm/ADT/STLExtras.h"
41 #include "llvm/Support/ErrorHandling.h"
42 using namespace clang;
43 using namespace sema;
44 
45 /// Handle the result of the special case name lookup for inheriting
46 /// constructor declarations. 'NS::X::X' and 'NS::X<...>::X' are treated as
47 /// constructor names in member using declarations, even if 'X' is not the
48 /// name of the corresponding type.
50  SourceLocation NameLoc,
51  IdentifierInfo &Name) {
52  NestedNameSpecifier *NNS = SS.getScopeRep();
53 
54  // Convert the nested-name-specifier into a type.
55  QualType Type;
56  switch (NNS->getKind()) {
59  Type = QualType(NNS->getAsType(), 0);
60  break;
61 
63  // Strip off the last layer of the nested-name-specifier and build a
64  // typename type for it.
65  assert(NNS->getAsIdentifier() == &Name && "not a constructor name");
66  Type = Context.getDependentNameType(ETK_None, NNS->getPrefix(),
67  NNS->getAsIdentifier());
68  break;
69 
74  llvm_unreachable("Nested name specifier is not a type for inheriting ctor");
75  }
76 
77  // This reference to the type is located entirely at the location of the
78  // final identifier in the qualified-id.
79  return CreateParsedType(Type,
80  Context.getTrivialTypeSourceInfo(Type, NameLoc));
81 }
82 
84  SourceLocation NameLoc,
85  Scope *S, CXXScopeSpec &SS,
86  bool EnteringContext) {
87  CXXRecordDecl *CurClass = getCurrentClass(S, &SS);
88  assert(CurClass && &II == CurClass->getIdentifier() &&
89  "not a constructor name");
90 
91  // When naming a constructor as a member of a dependent context (eg, in a
92  // friend declaration or an inherited constructor declaration), form an
93  // unresolved "typename" type.
94  if (CurClass->isDependentContext() && !EnteringContext && SS.getScopeRep()) {
95  QualType T = Context.getDependentNameType(ETK_None, SS.getScopeRep(), &II);
96  return ParsedType::make(T);
97  }
98 
99  if (SS.isNotEmpty() && RequireCompleteDeclContext(SS, CurClass))
100  return ParsedType();
101 
102  // Find the injected-class-name declaration. Note that we make no attempt to
103  // diagnose cases where the injected-class-name is shadowed: the only
104  // declaration that can validly shadow the injected-class-name is a
105  // non-static data member, and if the class contains both a non-static data
106  // member and a constructor then it is ill-formed (we check that in
107  // CheckCompletedCXXClass).
108  CXXRecordDecl *InjectedClassName = nullptr;
109  for (NamedDecl *ND : CurClass->lookup(&II)) {
110  auto *RD = dyn_cast<CXXRecordDecl>(ND);
111  if (RD && RD->isInjectedClassName()) {
112  InjectedClassName = RD;
113  break;
114  }
115  }
116  if (!InjectedClassName) {
117  if (!CurClass->isInvalidDecl()) {
118  // FIXME: RequireCompleteDeclContext doesn't check dependent contexts
119  // properly. Work around it here for now.
121  diag::err_incomplete_nested_name_spec) << CurClass << SS.getRange();
122  }
123  return ParsedType();
124  }
125 
126  QualType T = Context.getTypeDeclType(InjectedClassName);
127  DiagnoseUseOfDecl(InjectedClassName, NameLoc);
128  MarkAnyDeclReferenced(NameLoc, InjectedClassName, /*OdrUse=*/false);
129 
130  return ParsedType::make(T);
131 }
132 
134  IdentifierInfo &II,
135  SourceLocation NameLoc,
136  Scope *S, CXXScopeSpec &SS,
137  ParsedType ObjectTypePtr,
138  bool EnteringContext) {
139  // Determine where to perform name lookup.
140 
141  // FIXME: This area of the standard is very messy, and the current
142  // wording is rather unclear about which scopes we search for the
143  // destructor name; see core issues 399 and 555. Issue 399 in
144  // particular shows where the current description of destructor name
145  // lookup is completely out of line with existing practice, e.g.,
146  // this appears to be ill-formed:
147  //
148  // namespace N {
149  // template <typename T> struct S {
150  // ~S();
151  // };
152  // }
153  //
154  // void f(N::S<int>* s) {
155  // s->N::S<int>::~S();
156  // }
157  //
158  // See also PR6358 and PR6359.
159  //
160  // For now, we accept all the cases in which the name given could plausibly
161  // be interpreted as a correct destructor name, issuing off-by-default
162  // extension diagnostics on the cases that don't strictly conform to the
163  // C++20 rules. This basically means we always consider looking in the
164  // nested-name-specifier prefix, the complete nested-name-specifier, and
165  // the scope, and accept if we find the expected type in any of the three
166  // places.
167 
168  if (SS.isInvalid())
169  return nullptr;
170 
171  // Whether we've failed with a diagnostic already.
172  bool Failed = false;
173 
176 
177  // If we have an object type, it's because we are in a
178  // pseudo-destructor-expression or a member access expression, and
179  // we know what type we're looking for.
180  QualType SearchType =
181  ObjectTypePtr ? GetTypeFromParser(ObjectTypePtr) : QualType();
182 
183  auto CheckLookupResult = [&](LookupResult &Found) -> ParsedType {
184  auto IsAcceptableResult = [&](NamedDecl *D) -> bool {
185  auto *Type = dyn_cast<TypeDecl>(D->getUnderlyingDecl());
186  if (!Type)
187  return false;
188 
189  if (SearchType.isNull() || SearchType->isDependentType())
190  return true;
191 
192  QualType T = Context.getTypeDeclType(Type);
193  return Context.hasSameUnqualifiedType(T, SearchType);
194  };
195 
196  unsigned NumAcceptableResults = 0;
197  for (NamedDecl *D : Found) {
198  if (IsAcceptableResult(D))
199  ++NumAcceptableResults;
200 
201  // Don't list a class twice in the lookup failure diagnostic if it's
202  // found by both its injected-class-name and by the name in the enclosing
203  // scope.
204  if (auto *RD = dyn_cast<CXXRecordDecl>(D))
205  if (RD->isInjectedClassName())
206  D = cast<NamedDecl>(RD->getParent());
207 
208  if (FoundDeclSet.insert(D).second)
209  FoundDecls.push_back(D);
210  }
211 
212  // As an extension, attempt to "fix" an ambiguity by erasing all non-type
213  // results, and all non-matching results if we have a search type. It's not
214  // clear what the right behavior is if destructor lookup hits an ambiguity,
215  // but other compilers do generally accept at least some kinds of
216  // ambiguity.
217  if (Found.isAmbiguous() && NumAcceptableResults == 1) {
218  Diag(NameLoc, diag::ext_dtor_name_ambiguous);
219  LookupResult::Filter F = Found.makeFilter();
220  while (F.hasNext()) {
221  NamedDecl *D = F.next();
222  if (auto *TD = dyn_cast<TypeDecl>(D->getUnderlyingDecl()))
223  Diag(D->getLocation(), diag::note_destructor_type_here)
224  << Context.getTypeDeclType(TD);
225  else
226  Diag(D->getLocation(), diag::note_destructor_nontype_here);
227 
228  if (!IsAcceptableResult(D))
229  F.erase();
230  }
231  F.done();
232  }
233 
234  if (Found.isAmbiguous())
235  Failed = true;
236 
237  if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) {
238  if (IsAcceptableResult(Type)) {
239  QualType T = Context.getTypeDeclType(Type);
240  MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
241  return CreateParsedType(T,
242  Context.getTrivialTypeSourceInfo(T, NameLoc));
243  }
244  }
245 
246  return nullptr;
247  };
248 
249  bool IsDependent = false;
250 
251  auto LookupInObjectType = [&]() -> ParsedType {
252  if (Failed || SearchType.isNull())
253  return nullptr;
254 
255  IsDependent |= SearchType->isDependentType();
256 
257  LookupResult Found(*this, &II, NameLoc, LookupDestructorName);
258  DeclContext *LookupCtx = computeDeclContext(SearchType);
259  if (!LookupCtx)
260  return nullptr;
261  LookupQualifiedName(Found, LookupCtx);
262  return CheckLookupResult(Found);
263  };
264 
265  auto LookupInNestedNameSpec = [&](CXXScopeSpec &LookupSS) -> ParsedType {
266  if (Failed)
267  return nullptr;
268 
269  IsDependent |= isDependentScopeSpecifier(LookupSS);
270  DeclContext *LookupCtx = computeDeclContext(LookupSS, EnteringContext);
271  if (!LookupCtx)
272  return nullptr;
273 
274  LookupResult Found(*this, &II, NameLoc, LookupDestructorName);
275  if (RequireCompleteDeclContext(LookupSS, LookupCtx)) {
276  Failed = true;
277  return nullptr;
278  }
279  LookupQualifiedName(Found, LookupCtx);
280  return CheckLookupResult(Found);
281  };
282 
283  auto LookupInScope = [&]() -> ParsedType {
284  if (Failed || !S)
285  return nullptr;
286 
287  LookupResult Found(*this, &II, NameLoc, LookupDestructorName);
288  LookupName(Found, S);
289  return CheckLookupResult(Found);
290  };
291 
292  // C++2a [basic.lookup.qual]p6:
293  // In a qualified-id of the form
294  //
295  // nested-name-specifier[opt] type-name :: ~ type-name
296  //
297  // the second type-name is looked up in the same scope as the first.
298  //
299  // We interpret this as meaning that if you do a dual-scope lookup for the
300  // first name, you also do a dual-scope lookup for the second name, per
301  // C++ [basic.lookup.classref]p4:
302  //
303  // If the id-expression in a class member access is a qualified-id of the
304  // form
305  //
306  // class-name-or-namespace-name :: ...
307  //
308  // the class-name-or-namespace-name following the . or -> is first looked
309  // up in the class of the object expression and the name, if found, is used.
310  // Otherwise, it is looked up in the context of the entire
311  // postfix-expression.
312  //
313  // This looks in the same scopes as for an unqualified destructor name:
314  //
315  // C++ [basic.lookup.classref]p3:
316  // If the unqualified-id is ~ type-name, the type-name is looked up
317  // in the context of the entire postfix-expression. If the type T
318  // of the object expression is of a class type C, the type-name is
319  // also looked up in the scope of class C. At least one of the
320  // lookups shall find a name that refers to cv T.
321  //
322  // FIXME: The intent is unclear here. Should type-name::~type-name look in
323  // the scope anyway if it finds a non-matching name declared in the class?
324  // If both lookups succeed and find a dependent result, which result should
325  // we retain? (Same question for p->~type-name().)
326 
327  if (NestedNameSpecifier *Prefix =
328  SS.isSet() ? SS.getScopeRep()->getPrefix() : nullptr) {
329  // This is
330  //
331  // nested-name-specifier type-name :: ~ type-name
332  //
333  // Look for the second type-name in the nested-name-specifier.
334  CXXScopeSpec PrefixSS;
335  PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data()));
336  if (ParsedType T = LookupInNestedNameSpec(PrefixSS))
337  return T;
338  } else {
339  // This is one of
340  //
341  // type-name :: ~ type-name
342  // ~ type-name
343  //
344  // Look in the scope and (if any) the object type.
345  if (ParsedType T = LookupInScope())
346  return T;
347  if (ParsedType T = LookupInObjectType())
348  return T;
349  }
350 
351  if (Failed)
352  return nullptr;
353 
354  if (IsDependent) {
355  // We didn't find our type, but that's OK: it's dependent anyway.
356 
357  // FIXME: What if we have no nested-name-specifier?
358  QualType T = CheckTypenameType(ETK_None, SourceLocation(),
359  SS.getWithLocInContext(Context),
360  II, NameLoc);
361  return ParsedType::make(T);
362  }
363 
364  // The remaining cases are all non-standard extensions imitating the behavior
365  // of various other compilers.
366  unsigned NumNonExtensionDecls = FoundDecls.size();
367 
368  if (SS.isSet()) {
369  // For compatibility with older broken C++ rules and existing code,
370  //
371  // nested-name-specifier :: ~ type-name
372  //
373  // also looks for type-name within the nested-name-specifier.
374  if (ParsedType T = LookupInNestedNameSpec(SS)) {
375  Diag(SS.getEndLoc(), diag::ext_dtor_named_in_wrong_scope)
376  << SS.getRange()
378  ("::" + II.getName()).str());
379  return T;
380  }
381 
382  // For compatibility with other compilers and older versions of Clang,
383  //
384  // nested-name-specifier type-name :: ~ type-name
385  //
386  // also looks for type-name in the scope. Unfortunately, we can't
387  // reasonably apply this fallback for dependent nested-name-specifiers.
388  if (SS.getScopeRep()->getPrefix()) {
389  if (ParsedType T = LookupInScope()) {
390  Diag(SS.getEndLoc(), diag::ext_qualified_dtor_named_in_lexical_scope)
392  Diag(FoundDecls.back()->getLocation(), diag::note_destructor_type_here)
393  << GetTypeFromParser(T);
394  return T;
395  }
396  }
397  }
398 
399  // We didn't find anything matching; tell the user what we did find (if
400  // anything).
401 
402  // Don't tell the user about declarations we shouldn't have found.
403  FoundDecls.resize(NumNonExtensionDecls);
404 
405  // List types before non-types.
406  std::stable_sort(FoundDecls.begin(), FoundDecls.end(),
407  [](NamedDecl *A, NamedDecl *B) {
408  return isa<TypeDecl>(A->getUnderlyingDecl()) >
409  isa<TypeDecl>(B->getUnderlyingDecl());
410  });
411 
412  // Suggest a fixit to properly name the destroyed type.
413  auto MakeFixItHint = [&]{
414  const CXXRecordDecl *Destroyed = nullptr;
415  // FIXME: If we have a scope specifier, suggest its last component?
416  if (!SearchType.isNull())
417  Destroyed = SearchType->getAsCXXRecordDecl();
418  else if (S)
419  Destroyed = dyn_cast_or_null<CXXRecordDecl>(S->getEntity());
420  if (Destroyed)
422  Destroyed->getNameAsString());
423  return FixItHint();
424  };
425 
426  if (FoundDecls.empty()) {
427  // FIXME: Attempt typo-correction?
428  Diag(NameLoc, diag::err_undeclared_destructor_name)
429  << &II << MakeFixItHint();
430  } else if (!SearchType.isNull() && FoundDecls.size() == 1) {
431  if (auto *TD = dyn_cast<TypeDecl>(FoundDecls[0]->getUnderlyingDecl())) {
432  assert(!SearchType.isNull() &&
433  "should only reject a type result if we have a search type");
434  QualType T = Context.getTypeDeclType(TD);
435  Diag(NameLoc, diag::err_destructor_expr_type_mismatch)
436  << T << SearchType << MakeFixItHint();
437  } else {
438  Diag(NameLoc, diag::err_destructor_expr_nontype)
439  << &II << MakeFixItHint();
440  }
441  } else {
442  Diag(NameLoc, SearchType.isNull() ? diag::err_destructor_name_nontype
443  : diag::err_destructor_expr_mismatch)
444  << &II << SearchType << MakeFixItHint();
445  }
446 
447  for (NamedDecl *FoundD : FoundDecls) {
448  if (auto *TD = dyn_cast<TypeDecl>(FoundD->getUnderlyingDecl()))
449  Diag(FoundD->getLocation(), diag::note_destructor_type_here)
450  << Context.getTypeDeclType(TD);
451  else
452  Diag(FoundD->getLocation(), diag::note_destructor_nontype_here)
453  << FoundD;
454  }
455 
456  return nullptr;
457 }
458 
460  ParsedType ObjectType) {
462  return nullptr;
463 
465  Diag(DS.getTypeSpecTypeLoc(), diag::err_decltype_auto_invalid);
466  return nullptr;
467  }
468 
469  assert(DS.getTypeSpecType() == DeclSpec::TST_decltype &&
470  "unexpected type in getDestructorType");
471  QualType T = BuildDecltypeType(DS.getRepAsExpr());
472 
473  // If we know the type of the object, check that the correct destructor
474  // type was named now; we can give better diagnostics this way.
475  QualType SearchType = GetTypeFromParser(ObjectType);
476  if (!SearchType.isNull() && !SearchType->isDependentType() &&
477  !Context.hasSameUnqualifiedType(T, SearchType)) {
478  Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch)
479  << T << SearchType;
480  return nullptr;
481  }
482 
483  return ParsedType::make(T);
484 }
485 
487  const UnqualifiedId &Name, bool IsUDSuffix) {
488  assert(Name.getKind() == UnqualifiedIdKind::IK_LiteralOperatorId);
489  if (!IsUDSuffix) {
490  // [over.literal] p8
491  //
492  // double operator""_Bq(long double); // OK: not a reserved identifier
493  // double operator"" _Bq(long double); // ill-formed, no diagnostic required
494  IdentifierInfo *II = Name.Identifier;
495  ReservedIdentifierStatus Status = II->isReserved(PP.getLangOpts());
496  SourceLocation Loc = Name.getEndLoc();
497  if (isReservedInAllContexts(Status) &&
498  !PP.getSourceManager().isInSystemHeader(Loc)) {
499  Diag(Loc, diag::warn_reserved_extern_symbol)
500  << II << static_cast<int>(Status)
502  Name.getSourceRange(),
503  (StringRef("operator\"\"") + II->getName()).str());
504  }
505  }
506 
507  if (!SS.isValid())
508  return false;
509 
510  switch (SS.getScopeRep()->getKind()) {
514  // Per C++11 [over.literal]p2, literal operators can only be declared at
515  // namespace scope. Therefore, this unqualified-id cannot name anything.
516  // Reject it early, because we have no AST representation for this in the
517  // case where the scope is dependent.
518  Diag(Name.getBeginLoc(), diag::err_literal_operator_id_outside_namespace)
519  << SS.getScopeRep();
520  return true;
521 
526  return false;
527  }
528 
529  llvm_unreachable("unknown nested name specifier kind");
530 }
531 
532 /// Build a C++ typeid expression with a type operand.
534  SourceLocation TypeidLoc,
535  TypeSourceInfo *Operand,
536  SourceLocation RParenLoc) {
537  // C++ [expr.typeid]p4:
538  // The top-level cv-qualifiers of the lvalue expression or the type-id
539  // that is the operand of typeid are always ignored.
540  // If the type of the type-id is a class type or a reference to a class
541  // type, the class shall be completely-defined.
542  Qualifiers Quals;
543  QualType T
544  = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(),
545  Quals);
546  if (T->getAs<RecordType>() &&
547  RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
548  return ExprError();
549 
550  if (T->isVariablyModifiedType())
551  return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid) << T);
552 
553  if (CheckQualifiedFunctionForTypeId(T, TypeidLoc))
554  return ExprError();
555 
556  return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), Operand,
557  SourceRange(TypeidLoc, RParenLoc));
558 }
559 
560 /// Build a C++ typeid expression with an expression operand.
562  SourceLocation TypeidLoc,
563  Expr *E,
564  SourceLocation RParenLoc) {
565  bool WasEvaluated = false;
566  if (E && !E->isTypeDependent()) {
567  if (E->getType()->isPlaceholderType()) {
568  ExprResult result = CheckPlaceholderExpr(E);
569  if (result.isInvalid()) return ExprError();
570  E = result.get();
571  }
572 
573  QualType T = E->getType();
574  if (const RecordType *RecordT = T->getAs<RecordType>()) {
575  CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl());
576  // C++ [expr.typeid]p3:
577  // [...] If the type of the expression is a class type, the class
578  // shall be completely-defined.
579  if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
580  return ExprError();
581 
582  // C++ [expr.typeid]p3:
583  // When typeid is applied to an expression other than an glvalue of a
584  // polymorphic class type [...] [the] expression is an unevaluated
585  // operand. [...]
586  if (RecordD->isPolymorphic() && E->isGLValue()) {
587  if (isUnevaluatedContext()) {
588  // The operand was processed in unevaluated context, switch the
589  // context and recheck the subexpression.
590  ExprResult Result = TransformToPotentiallyEvaluated(E);
591  if (Result.isInvalid())
592  return ExprError();
593  E = Result.get();
594  }
595 
596  // We require a vtable to query the type at run time.
597  MarkVTableUsed(TypeidLoc, RecordD);
598  WasEvaluated = true;
599  }
600  }
601 
602  ExprResult Result = CheckUnevaluatedOperand(E);
603  if (Result.isInvalid())
604  return ExprError();
605  E = Result.get();
606 
607  // C++ [expr.typeid]p4:
608  // [...] If the type of the type-id is a reference to a possibly
609  // cv-qualified type, the result of the typeid expression refers to a
610  // std::type_info object representing the cv-unqualified referenced
611  // type.
612  Qualifiers Quals;
613  QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals);
614  if (!Context.hasSameType(T, UnqualT)) {
615  T = UnqualT;
616  E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).get();
617  }
618  }
619 
620  if (E->getType()->isVariablyModifiedType())
621  return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid)
622  << E->getType());
623  else if (!inTemplateInstantiation() &&
624  E->HasSideEffects(Context, WasEvaluated)) {
625  // The expression operand for typeid is in an unevaluated expression
626  // context, so side effects could result in unintended consequences.
627  Diag(E->getExprLoc(), WasEvaluated
628  ? diag::warn_side_effects_typeid
629  : diag::warn_side_effects_unevaluated_context);
630  }
631 
632  return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), E,
633  SourceRange(TypeidLoc, RParenLoc));
634 }
635 
636 /// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression);
639  bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
640  // typeid is not supported in OpenCL.
641  if (getLangOpts().OpenCLCPlusPlus) {
642  return ExprError(Diag(OpLoc, diag::err_openclcxx_not_supported)
643  << "typeid");
644  }
645 
646  // Find the std::type_info type.
647  if (!getStdNamespace())
648  return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
649 
650  if (!CXXTypeInfoDecl) {
651  IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info");
652  LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName);
653  LookupQualifiedName(R, getStdNamespace());
654  CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
655  // Microsoft's typeinfo doesn't have type_info in std but in the global
656  // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153.
657  if (!CXXTypeInfoDecl && LangOpts.MSVCCompat) {
658  LookupQualifiedName(R, Context.getTranslationUnitDecl());
659  CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
660  }
661  if (!CXXTypeInfoDecl)
662  return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
663  }
664 
665  if (!getLangOpts().RTTI) {
666  return ExprError(Diag(OpLoc, diag::err_no_typeid_with_fno_rtti));
667  }
668 
669  QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl);
670 
671  if (isType) {
672  // The operand is a type; handle it as such.
673  TypeSourceInfo *TInfo = nullptr;
674  QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
675  &TInfo);
676  if (T.isNull())
677  return ExprError();
678 
679  if (!TInfo)
680  TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
681 
682  return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc);
683  }
684 
685  // The operand is an expression.
686  ExprResult Result =
687  BuildCXXTypeId(TypeInfoType, OpLoc, (Expr *)TyOrExpr, RParenLoc);
688 
689  if (!getLangOpts().RTTIData && !Result.isInvalid())
690  if (auto *CTE = dyn_cast<CXXTypeidExpr>(Result.get()))
691  if (CTE->isPotentiallyEvaluated() && !CTE->isMostDerived(Context))
692  Diag(OpLoc, diag::warn_no_typeid_with_rtti_disabled)
693  << (getDiagnostics().getDiagnosticOptions().getFormat() ==
695  return Result;
696 }
697 
698 /// Grabs __declspec(uuid()) off a type, or returns 0 if we cannot resolve to
699 /// a single GUID.
700 static void
703  // Optionally remove one level of pointer, reference or array indirection.
704  const Type *Ty = QT.getTypePtr();
705  if (QT->isPointerType() || QT->isReferenceType())
706  Ty = QT->getPointeeType().getTypePtr();
707  else if (QT->isArrayType())
708  Ty = Ty->getBaseElementTypeUnsafe();
709 
710  const auto *TD = Ty->getAsTagDecl();
711  if (!TD)
712  return;
713 
714  if (const auto *Uuid = TD->getMostRecentDecl()->getAttr<UuidAttr>()) {
715  UuidAttrs.insert(Uuid);
716  return;
717  }
718 
719  // __uuidof can grab UUIDs from template arguments.
720  if (const auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(TD)) {
721  const TemplateArgumentList &TAL = CTSD->getTemplateArgs();
722  for (const TemplateArgument &TA : TAL.asArray()) {
723  const UuidAttr *UuidForTA = nullptr;
724  if (TA.getKind() == TemplateArgument::Type)
725  getUuidAttrOfType(SemaRef, TA.getAsType(), UuidAttrs);
726  else if (TA.getKind() == TemplateArgument::Declaration)
727  getUuidAttrOfType(SemaRef, TA.getAsDecl()->getType(), UuidAttrs);
728 
729  if (UuidForTA)
730  UuidAttrs.insert(UuidForTA);
731  }
732  }
733 }
734 
735 /// Build a Microsoft __uuidof expression with a type operand.
737  SourceLocation TypeidLoc,
738  TypeSourceInfo *Operand,
739  SourceLocation RParenLoc) {
740  MSGuidDecl *Guid = nullptr;
741  if (!Operand->getType()->isDependentType()) {
743  getUuidAttrOfType(*this, Operand->getType(), UuidAttrs);
744  if (UuidAttrs.empty())
745  return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
746  if (UuidAttrs.size() > 1)
747  return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
748  Guid = UuidAttrs.back()->getGuidDecl();
749  }
750 
751  return new (Context)
752  CXXUuidofExpr(Type, Operand, Guid, SourceRange(TypeidLoc, RParenLoc));
753 }
754 
755 /// Build a Microsoft __uuidof expression with an expression operand.
757  Expr *E, SourceLocation RParenLoc) {
758  MSGuidDecl *Guid = nullptr;
759  if (!E->getType()->isDependentType()) {
761  // A null pointer results in {00000000-0000-0000-0000-000000000000}.
762  Guid = Context.getMSGuidDecl(MSGuidDecl::Parts{});
763  } else {
765  getUuidAttrOfType(*this, E->getType(), UuidAttrs);
766  if (UuidAttrs.empty())
767  return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
768  if (UuidAttrs.size() > 1)
769  return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
770  Guid = UuidAttrs.back()->getGuidDecl();
771  }
772  }
773 
774  return new (Context)
775  CXXUuidofExpr(Type, E, Guid, SourceRange(TypeidLoc, RParenLoc));
776 }
777 
778 /// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression);
781  bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
782  QualType GuidType = Context.getMSGuidType();
783  GuidType.addConst();
784 
785  if (isType) {
786  // The operand is a type; handle it as such.
787  TypeSourceInfo *TInfo = nullptr;
788  QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
789  &TInfo);
790  if (T.isNull())
791  return ExprError();
792 
793  if (!TInfo)
794  TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
795 
796  return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc);
797  }
798 
799  // The operand is an expression.
800  return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
801 }
802 
803 /// ActOnCXXBoolLiteral - Parse {true,false} literals.
806  assert((Kind == tok::kw_true || Kind == tok::kw_false) &&
807  "Unknown C++ Boolean value!");
808  return new (Context)
809  CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc);
810 }
811 
812 /// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
815  return new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
816 }
817 
818 /// ActOnCXXThrow - Parse throw expressions.
821  bool IsThrownVarInScope = false;
822  if (Ex) {
823  // C++0x [class.copymove]p31:
824  // When certain criteria are met, an implementation is allowed to omit the
825  // copy/move construction of a class object [...]
826  //
827  // - in a throw-expression, when the operand is the name of a
828  // non-volatile automatic object (other than a function or catch-
829  // clause parameter) whose scope does not extend beyond the end of the
830  // innermost enclosing try-block (if there is one), the copy/move
831  // operation from the operand to the exception object (15.1) can be
832  // omitted by constructing the automatic object directly into the
833  // exception object
834  if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens()))
835  if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
836  if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) {
837  for( ; S; S = S->getParent()) {
838  if (S->isDeclScope(Var)) {
839  IsThrownVarInScope = true;
840  break;
841  }
842 
843  if (S->getFlags() &
847  break;
848  }
849  }
850  }
851  }
852 
853  return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope);
854 }
855 
857  bool IsThrownVarInScope) {
858  // Don't report an error if 'throw' is used in system headers.
859  if (!getLangOpts().CXXExceptions &&
860  !getSourceManager().isInSystemHeader(OpLoc) && !getLangOpts().CUDA) {
861  // Delay error emission for the OpenMP device code.
862  targetDiag(OpLoc, diag::err_exceptions_disabled) << "throw";
863  }
864 
865  // Exceptions aren't allowed in CUDA device code.
866  if (getLangOpts().CUDA)
867  CUDADiagIfDeviceCode(OpLoc, diag::err_cuda_device_exceptions)
868  << "throw" << CurrentCUDATarget();
869 
870  if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
871  Diag(OpLoc, diag::err_omp_simd_region_cannot_use_stmt) << "throw";
872 
873  if (Ex && !Ex->isTypeDependent()) {
874  // Initialize the exception result. This implicitly weeds out
875  // abstract types or types with inaccessible copy constructors.
876 
877  // C++0x [class.copymove]p31:
878  // When certain criteria are met, an implementation is allowed to omit the
879  // copy/move construction of a class object [...]
880  //
881  // - in a throw-expression, when the operand is the name of a
882  // non-volatile automatic object (other than a function or
883  // catch-clause
884  // parameter) whose scope does not extend beyond the end of the
885  // innermost enclosing try-block (if there is one), the copy/move
886  // operation from the operand to the exception object (15.1) can be
887  // omitted by constructing the automatic object directly into the
888  // exception object
889  NamedReturnInfo NRInfo =
890  IsThrownVarInScope ? getNamedReturnInfo(Ex) : NamedReturnInfo();
891 
892  QualType ExceptionObjectTy = Context.getExceptionObjectType(Ex->getType());
893  if (CheckCXXThrowOperand(OpLoc, ExceptionObjectTy, Ex))
894  return ExprError();
895 
896  InitializedEntity Entity =
897  InitializedEntity::InitializeException(OpLoc, ExceptionObjectTy);
898  ExprResult Res = PerformMoveOrCopyInitialization(Entity, NRInfo, Ex);
899  if (Res.isInvalid())
900  return ExprError();
901  Ex = Res.get();
902  }
903 
904  // PPC MMA non-pointer types are not allowed as throw expr types.
905  if (Ex && Context.getTargetInfo().getTriple().isPPC64())
906  CheckPPCMMAType(Ex->getType(), Ex->getBeginLoc());
907 
908  return new (Context)
909  CXXThrowExpr(Ex, Context.VoidTy, OpLoc, IsThrownVarInScope);
910 }
911 
912 static void
914  llvm::DenseMap<CXXRecordDecl *, unsigned> &SubobjectsSeen,
915  llvm::SmallPtrSetImpl<CXXRecordDecl *> &VBases,
916  llvm::SetVector<CXXRecordDecl *> &PublicSubobjectsSeen,
917  bool ParentIsPublic) {
918  for (const CXXBaseSpecifier &BS : RD->bases()) {
919  CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
920  bool NewSubobject;
921  // Virtual bases constitute the same subobject. Non-virtual bases are
922  // always distinct subobjects.
923  if (BS.isVirtual())
924  NewSubobject = VBases.insert(BaseDecl).second;
925  else
926  NewSubobject = true;
927 
928  if (NewSubobject)
929  ++SubobjectsSeen[BaseDecl];
930 
931  // Only add subobjects which have public access throughout the entire chain.
932  bool PublicPath = ParentIsPublic && BS.getAccessSpecifier() == AS_public;
933  if (PublicPath)
934  PublicSubobjectsSeen.insert(BaseDecl);
935 
936  // Recurse on to each base subobject.
937  collectPublicBases(BaseDecl, SubobjectsSeen, VBases, PublicSubobjectsSeen,
938  PublicPath);
939  }
940 }
941 
944  llvm::DenseMap<CXXRecordDecl *, unsigned> SubobjectsSeen;
945  llvm::SmallSet<CXXRecordDecl *, 2> VBases;
946  llvm::SetVector<CXXRecordDecl *> PublicSubobjectsSeen;
947  SubobjectsSeen[RD] = 1;
948  PublicSubobjectsSeen.insert(RD);
949  collectPublicBases(RD, SubobjectsSeen, VBases, PublicSubobjectsSeen,
950  /*ParentIsPublic=*/true);
951 
952  for (CXXRecordDecl *PublicSubobject : PublicSubobjectsSeen) {
953  // Skip ambiguous objects.
954  if (SubobjectsSeen[PublicSubobject] > 1)
955  continue;
956 
957  Objects.push_back(PublicSubobject);
958  }
959 }
960 
961 /// CheckCXXThrowOperand - Validate the operand of a throw.
963  QualType ExceptionObjectTy, Expr *E) {
964  // If the type of the exception would be an incomplete type or a pointer
965  // to an incomplete type other than (cv) void the program is ill-formed.
966  QualType Ty = ExceptionObjectTy;
967  bool isPointer = false;
968  if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
969  Ty = Ptr->getPointeeType();
970  isPointer = true;
971  }
972  if (!isPointer || !Ty->isVoidType()) {
973  if (RequireCompleteType(ThrowLoc, Ty,
974  isPointer ? diag::err_throw_incomplete_ptr
975  : diag::err_throw_incomplete,
976  E->getSourceRange()))
977  return true;
978 
979  if (!isPointer && Ty->isSizelessType()) {
980  Diag(ThrowLoc, diag::err_throw_sizeless) << Ty << E->getSourceRange();
981  return true;
982  }
983 
984  if (RequireNonAbstractType(ThrowLoc, ExceptionObjectTy,
985  diag::err_throw_abstract_type, E))
986  return true;
987  }
988 
989  // If the exception has class type, we need additional handling.
990  CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
991  if (!RD)
992  return false;
993 
994  // If we are throwing a polymorphic class type or pointer thereof,
995  // exception handling will make use of the vtable.
996  MarkVTableUsed(ThrowLoc, RD);
997 
998  // If a pointer is thrown, the referenced object will not be destroyed.
999  if (isPointer)
1000  return false;
1001 
1002  // If the class has a destructor, we must be able to call it.
1003  if (!RD->hasIrrelevantDestructor()) {
1004  if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
1005  MarkFunctionReferenced(E->getExprLoc(), Destructor);
1006  CheckDestructorAccess(E->getExprLoc(), Destructor,
1007  PDiag(diag::err_access_dtor_exception) << Ty);
1008  if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
1009  return true;
1010  }
1011  }
1012 
1013  // The MSVC ABI creates a list of all types which can catch the exception
1014  // object. This list also references the appropriate copy constructor to call
1015  // if the object is caught by value and has a non-trivial copy constructor.
1016  if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
1017  // We are only interested in the public, unambiguous bases contained within
1018  // the exception object. Bases which are ambiguous or otherwise
1019  // inaccessible are not catchable types.
1020  llvm::SmallVector<CXXRecordDecl *, 2> UnambiguousPublicSubobjects;
1021  getUnambiguousPublicSubobjects(RD, UnambiguousPublicSubobjects);
1022 
1023  for (CXXRecordDecl *Subobject : UnambiguousPublicSubobjects) {
1024  // Attempt to lookup the copy constructor. Various pieces of machinery
1025  // will spring into action, like template instantiation, which means this
1026  // cannot be a simple walk of the class's decls. Instead, we must perform
1027  // lookup and overload resolution.
1028  CXXConstructorDecl *CD = LookupCopyingConstructor(Subobject, 0);
1029  if (!CD || CD->isDeleted())
1030  continue;
1031 
1032  // Mark the constructor referenced as it is used by this throw expression.
1033  MarkFunctionReferenced(E->getExprLoc(), CD);
1034 
1035  // Skip this copy constructor if it is trivial, we don't need to record it
1036  // in the catchable type data.
1037  if (CD->isTrivial())
1038  continue;
1039 
1040  // The copy constructor is non-trivial, create a mapping from this class
1041  // type to this constructor.
1042  // N.B. The selection of copy constructor is not sensitive to this
1043  // particular throw-site. Lookup will be performed at the catch-site to
1044  // ensure that the copy constructor is, in fact, accessible (via
1045  // friendship or any other means).
1046  Context.addCopyConstructorForExceptionObject(Subobject, CD);
1047 
1048  // We don't keep the instantiated default argument expressions around so
1049  // we must rebuild them here.
1050  for (unsigned I = 1, E = CD->getNumParams(); I != E; ++I) {
1051  if (CheckCXXDefaultArgExpr(ThrowLoc, CD, CD->getParamDecl(I)))
1052  return true;
1053  }
1054  }
1055  }
1056 
1057  // Under the Itanium C++ ABI, memory for the exception object is allocated by
1058  // the runtime with no ability for the compiler to request additional
1059  // alignment. Warn if the exception type requires alignment beyond the minimum
1060  // guaranteed by the target C++ runtime.
1061  if (Context.getTargetInfo().getCXXABI().isItaniumFamily()) {
1062  CharUnits TypeAlign = Context.getTypeAlignInChars(Ty);
1063  CharUnits ExnObjAlign = Context.getExnObjectAlignment();
1064  if (ExnObjAlign < TypeAlign) {
1065  Diag(ThrowLoc, diag::warn_throw_underaligned_obj);
1066  Diag(ThrowLoc, diag::note_throw_underaligned_obj)
1067  << Ty << (unsigned)TypeAlign.getQuantity()
1068  << (unsigned)ExnObjAlign.getQuantity();
1069  }
1070  }
1071 
1072  return false;
1073 }
1074 
1076  ArrayRef<FunctionScopeInfo *> FunctionScopes, QualType ThisTy,
1077  DeclContext *CurSemaContext, ASTContext &ASTCtx) {
1078 
1079  QualType ClassType = ThisTy->getPointeeType();
1080  LambdaScopeInfo *CurLSI = nullptr;
1081  DeclContext *CurDC = CurSemaContext;
1082 
1083  // Iterate through the stack of lambdas starting from the innermost lambda to
1084  // the outermost lambda, checking if '*this' is ever captured by copy - since
1085  // that could change the cv-qualifiers of the '*this' object.
1086  // The object referred to by '*this' starts out with the cv-qualifiers of its
1087  // member function. We then start with the innermost lambda and iterate
1088  // outward checking to see if any lambda performs a by-copy capture of '*this'
1089  // - and if so, any nested lambda must respect the 'constness' of that
1090  // capturing lamdbda's call operator.
1091  //
1092 
1093  // Since the FunctionScopeInfo stack is representative of the lexical
1094  // nesting of the lambda expressions during initial parsing (and is the best
1095  // place for querying information about captures about lambdas that are
1096  // partially processed) and perhaps during instantiation of function templates
1097  // that contain lambda expressions that need to be transformed BUT not
1098  // necessarily during instantiation of a nested generic lambda's function call
1099  // operator (which might even be instantiated at the end of the TU) - at which
1100  // time the DeclContext tree is mature enough to query capture information
1101  // reliably - we use a two pronged approach to walk through all the lexically
1102  // enclosing lambda expressions:
1103  //
1104  // 1) Climb down the FunctionScopeInfo stack as long as each item represents
1105  // a Lambda (i.e. LambdaScopeInfo) AND each LSI's 'closure-type' is lexically
1106  // enclosed by the call-operator of the LSI below it on the stack (while
1107  // tracking the enclosing DC for step 2 if needed). Note the topmost LSI on
1108  // the stack represents the innermost lambda.
1109  //
1110  // 2) If we run out of enclosing LSI's, check if the enclosing DeclContext
1111  // represents a lambda's call operator. If it does, we must be instantiating
1112  // a generic lambda's call operator (represented by the Current LSI, and
1113  // should be the only scenario where an inconsistency between the LSI and the
1114  // DeclContext should occur), so climb out the DeclContexts if they
1115  // represent lambdas, while querying the corresponding closure types
1116  // regarding capture information.
1117 
1118  // 1) Climb down the function scope info stack.
1119  for (int I = FunctionScopes.size();
1120  I-- && isa<LambdaScopeInfo>(FunctionScopes[I]) &&
1121  (!CurLSI || !CurLSI->Lambda || CurLSI->Lambda->getDeclContext() ==
1122  cast<LambdaScopeInfo>(FunctionScopes[I])->CallOperator);
1123  CurDC = getLambdaAwareParentOfDeclContext(CurDC)) {
1124  CurLSI = cast<LambdaScopeInfo>(FunctionScopes[I]);
1125 
1126  if (!CurLSI->isCXXThisCaptured())
1127  continue;
1128 
1129  auto C = CurLSI->getCXXThisCapture();
1130 
1131  if (C.isCopyCapture()) {
1133  if (CurLSI->CallOperator->isConst())
1134  ClassType.addConst();
1135  return ASTCtx.getPointerType(ClassType);
1136  }
1137  }
1138 
1139  // 2) We've run out of ScopeInfos but check 1. if CurDC is a lambda (which
1140  // can happen during instantiation of its nested generic lambda call
1141  // operator); 2. if we're in a lambda scope (lambda body).
1142  if (CurLSI && isLambdaCallOperator(CurDC)) {
1144  "While computing 'this' capture-type for a generic lambda, when we "
1145  "run out of enclosing LSI's, yet the enclosing DC is a "
1146  "lambda-call-operator we must be (i.e. Current LSI) in a generic "
1147  "lambda call oeprator");
1148  assert(CurDC == getLambdaAwareParentOfDeclContext(CurLSI->CallOperator));
1149 
1150  auto IsThisCaptured =
1151  [](CXXRecordDecl *Closure, bool &IsByCopy, bool &IsConst) {
1152  IsConst = false;
1153  IsByCopy = false;
1154  for (auto &&C : Closure->captures()) {
1155  if (C.capturesThis()) {
1156  if (C.getCaptureKind() == LCK_StarThis)
1157  IsByCopy = true;
1158  if (Closure->getLambdaCallOperator()->isConst())
1159  IsConst = true;
1160  return true;
1161  }
1162  }
1163  return false;
1164  };
1165 
1166  bool IsByCopyCapture = false;
1167  bool IsConstCapture = false;
1168  CXXRecordDecl *Closure = cast<CXXRecordDecl>(CurDC->getParent());
1169  while (Closure &&
1170  IsThisCaptured(Closure, IsByCopyCapture, IsConstCapture)) {
1171  if (IsByCopyCapture) {
1173  if (IsConstCapture)
1174  ClassType.addConst();
1175  return ASTCtx.getPointerType(ClassType);
1176  }
1177  Closure = isLambdaCallOperator(Closure->getParent())
1178  ? cast<CXXRecordDecl>(Closure->getParent()->getParent())
1179  : nullptr;
1180  }
1181  }
1182  return ASTCtx.getPointerType(ClassType);
1183 }
1184 
1186  DeclContext *DC = getFunctionLevelDeclContext();
1187  QualType ThisTy = CXXThisTypeOverride;
1188 
1189  if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) {
1190  if (method && method->isInstance())
1191  ThisTy = method->getThisType();
1192  }
1193 
1194  if (ThisTy.isNull() && isLambdaCallOperator(CurContext) &&
1195  inTemplateInstantiation() && isa<CXXRecordDecl>(DC)) {
1196 
1197  // This is a lambda call operator that is being instantiated as a default
1198  // initializer. DC must point to the enclosing class type, so we can recover
1199  // the 'this' type from it.
1200  QualType ClassTy = Context.getTypeDeclType(cast<CXXRecordDecl>(DC));
1201  // There are no cv-qualifiers for 'this' within default initializers,
1202  // per [expr.prim.general]p4.
1203  ThisTy = Context.getPointerType(ClassTy);
1204  }
1205 
1206  // If we are within a lambda's call operator, the cv-qualifiers of 'this'
1207  // might need to be adjusted if the lambda or any of its enclosing lambda's
1208  // captures '*this' by copy.
1209  if (!ThisTy.isNull() && isLambdaCallOperator(CurContext))
1210  return adjustCVQualifiersForCXXThisWithinLambda(FunctionScopes, ThisTy,
1211  CurContext, Context);
1212  return ThisTy;
1213 }
1214 
1216  Decl *ContextDecl,
1217  Qualifiers CXXThisTypeQuals,
1218  bool Enabled)
1219  : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false)
1220 {
1221  if (!Enabled || !ContextDecl)
1222  return;
1223 
1224  CXXRecordDecl *Record = nullptr;
1225  if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl))
1226  Record = Template->getTemplatedDecl();
1227  else
1228  Record = cast<CXXRecordDecl>(ContextDecl);
1229 
1230  QualType T = S.Context.getRecordType(Record);
1231  T = S.getASTContext().getQualifiedType(T, CXXThisTypeQuals);
1232 
1234 
1235  this->Enabled = true;
1236 }
1237 
1238 
1240  if (Enabled) {
1241  S.CXXThisTypeOverride = OldCXXThisTypeOverride;
1242  }
1243 }
1244 
1246  SourceLocation DiagLoc = LSI->IntroducerRange.getEnd();
1247  assert(!LSI->isCXXThisCaptured());
1248  // [=, this] {}; // until C++20: Error: this when = is the default
1250  !Sema.getLangOpts().CPlusPlus20)
1251  return;
1252  Sema.Diag(DiagLoc, diag::note_lambda_this_capture_fixit)
1254  DiagLoc, LSI->NumExplicitCaptures > 0 ? ", this" : "this");
1255 }
1256 
1257 bool Sema::CheckCXXThisCapture(SourceLocation Loc, const bool Explicit,
1258  bool BuildAndDiagnose, const unsigned *const FunctionScopeIndexToStopAt,
1259  const bool ByCopy) {
1260  // We don't need to capture this in an unevaluated context.
1261  if (isUnevaluatedContext() && !Explicit)
1262  return true;
1263 
1264  assert((!ByCopy || Explicit) && "cannot implicitly capture *this by value");
1265 
1266  const int MaxFunctionScopesIndex = FunctionScopeIndexToStopAt
1267  ? *FunctionScopeIndexToStopAt
1268  : FunctionScopes.size() - 1;
1269 
1270  // Check that we can capture the *enclosing object* (referred to by '*this')
1271  // by the capturing-entity/closure (lambda/block/etc) at
1272  // MaxFunctionScopesIndex-deep on the FunctionScopes stack.
1273 
1274  // Note: The *enclosing object* can only be captured by-value by a
1275  // closure that is a lambda, using the explicit notation:
1276  // [*this] { ... }.
1277  // Every other capture of the *enclosing object* results in its by-reference
1278  // capture.
1279 
1280  // For a closure 'L' (at MaxFunctionScopesIndex in the FunctionScopes
1281  // stack), we can capture the *enclosing object* only if:
1282  // - 'L' has an explicit byref or byval capture of the *enclosing object*
1283  // - or, 'L' has an implicit capture.
1284  // AND
1285  // -- there is no enclosing closure
1286  // -- or, there is some enclosing closure 'E' that has already captured the
1287  // *enclosing object*, and every intervening closure (if any) between 'E'
1288  // and 'L' can implicitly capture the *enclosing object*.
1289  // -- or, every enclosing closure can implicitly capture the
1290  // *enclosing object*
1291 
1292 
1293  unsigned NumCapturingClosures = 0;
1294  for (int idx = MaxFunctionScopesIndex; idx >= 0; idx--) {
1295  if (CapturingScopeInfo *CSI =
1296  dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) {
1297  if (CSI->CXXThisCaptureIndex != 0) {
1298  // 'this' is already being captured; there isn't anything more to do.
1299  CSI->Captures[CSI->CXXThisCaptureIndex - 1].markUsed(BuildAndDiagnose);
1300  break;
1301  }
1302  LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI);
1304  // This context can't implicitly capture 'this'; fail out.
1305  if (BuildAndDiagnose) {
1306  Diag(Loc, diag::err_this_capture)
1307  << (Explicit && idx == MaxFunctionScopesIndex);
1308  if (!Explicit)
1309  buildLambdaThisCaptureFixit(*this, LSI);
1310  }
1311  return true;
1312  }
1313  if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref ||
1314  CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval ||
1315  CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block ||
1316  CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_CapturedRegion ||
1317  (Explicit && idx == MaxFunctionScopesIndex)) {
1318  // Regarding (Explicit && idx == MaxFunctionScopesIndex): only the first
1319  // iteration through can be an explicit capture, all enclosing closures,
1320  // if any, must perform implicit captures.
1321 
1322  // This closure can capture 'this'; continue looking upwards.
1323  NumCapturingClosures++;
1324  continue;
1325  }
1326  // This context can't implicitly capture 'this'; fail out.
1327  if (BuildAndDiagnose)
1328  Diag(Loc, diag::err_this_capture)
1329  << (Explicit && idx == MaxFunctionScopesIndex);
1330 
1331  if (!Explicit)
1332  buildLambdaThisCaptureFixit(*this, LSI);
1333  return true;
1334  }
1335  break;
1336  }
1337  if (!BuildAndDiagnose) return false;
1338 
1339  // If we got here, then the closure at MaxFunctionScopesIndex on the
1340  // FunctionScopes stack, can capture the *enclosing object*, so capture it
1341  // (including implicit by-reference captures in any enclosing closures).
1342 
1343  // In the loop below, respect the ByCopy flag only for the closure requesting
1344  // the capture (i.e. first iteration through the loop below). Ignore it for
1345  // all enclosing closure's up to NumCapturingClosures (since they must be
1346  // implicitly capturing the *enclosing object* by reference (see loop
1347  // above)).
1348  assert((!ByCopy ||
1349  dyn_cast<LambdaScopeInfo>(FunctionScopes[MaxFunctionScopesIndex])) &&
1350  "Only a lambda can capture the enclosing object (referred to by "
1351  "*this) by copy");
1352  QualType ThisTy = getCurrentThisType();
1353  for (int idx = MaxFunctionScopesIndex; NumCapturingClosures;
1354  --idx, --NumCapturingClosures) {
1355  CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]);
1356 
1357  // The type of the corresponding data member (not a 'this' pointer if 'by
1358  // copy').
1359  QualType CaptureType = ThisTy;
1360  if (ByCopy) {
1361  // If we are capturing the object referred to by '*this' by copy, ignore
1362  // any cv qualifiers inherited from the type of the member function for
1363  // the type of the closure-type's corresponding data member and any use
1364  // of 'this'.
1365  CaptureType = ThisTy->getPointeeType();
1367  }
1368 
1369  bool isNested = NumCapturingClosures > 1;
1370  CSI->addThisCapture(isNested, Loc, CaptureType, ByCopy);
1371  }
1372  return false;
1373 }
1374 
1376  /// C++ 9.3.2: In the body of a non-static member function, the keyword this
1377  /// is a non-lvalue expression whose value is the address of the object for
1378  /// which the function is called.
1379 
1380  QualType ThisTy = getCurrentThisType();
1381  if (ThisTy.isNull())
1382  return Diag(Loc, diag::err_invalid_this_use);
1383  return BuildCXXThisExpr(Loc, ThisTy, /*IsImplicit=*/false);
1384 }
1385 
1387  bool IsImplicit) {
1388  auto *This = new (Context) CXXThisExpr(Loc, Type, IsImplicit);
1390  return This;
1391 }
1392 
1394  CheckCXXThisCapture(This->getExprLoc());
1395 }
1396 
1398  // If we're outside the body of a member function, then we'll have a specified
1399  // type for 'this'.
1401  return false;
1402 
1403  // Determine whether we're looking into a class that's currently being
1404  // defined.
1405  CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl();
1406  return Class && Class->isBeingDefined();
1407 }
1408 
1409 /// Parse construction of a specified type.
1410 /// Can be interpreted either as function-style casting ("int(x)")
1411 /// or class type construction ("ClassType(x,y,z)")
1412 /// or creation of a value-initialized type ("int()").
1413 ExprResult
1415  SourceLocation LParenOrBraceLoc,
1416  MultiExprArg exprs,
1417  SourceLocation RParenOrBraceLoc,
1418  bool ListInitialization) {
1419  if (!TypeRep)
1420  return ExprError();
1421 
1422  TypeSourceInfo *TInfo;
1423  QualType Ty = GetTypeFromParser(TypeRep, &TInfo);
1424  if (!TInfo)
1426 
1427  auto Result = BuildCXXTypeConstructExpr(TInfo, LParenOrBraceLoc, exprs,
1428  RParenOrBraceLoc, ListInitialization);
1429  // Avoid creating a non-type-dependent expression that contains typos.
1430  // Non-type-dependent expressions are liable to be discarded without
1431  // checking for embedded typos.
1432  if (!Result.isInvalid() && Result.get()->isInstantiationDependent() &&
1433  !Result.get()->isTypeDependent())
1434  Result = CorrectDelayedTyposInExpr(Result.get());
1435  else if (Result.isInvalid())
1436  Result = CreateRecoveryExpr(TInfo->getTypeLoc().getBeginLoc(),
1437  RParenOrBraceLoc, exprs, Ty);
1438  return Result;
1439 }
1440 
1441 ExprResult
1443  SourceLocation LParenOrBraceLoc,
1444  MultiExprArg Exprs,
1445  SourceLocation RParenOrBraceLoc,
1446  bool ListInitialization) {
1447  QualType Ty = TInfo->getType();
1448  SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc();
1449 
1450  assert((!ListInitialization ||
1451  (Exprs.size() == 1 && isa<InitListExpr>(Exprs[0]))) &&
1452  "List initialization must have initializer list as expression.");
1453  SourceRange FullRange = SourceRange(TyBeginLoc, RParenOrBraceLoc);
1454 
1455  InitializedEntity Entity =
1458  Exprs.size()
1459  ? ListInitialization
1461  TyBeginLoc, LParenOrBraceLoc, RParenOrBraceLoc)
1462  : InitializationKind::CreateDirect(TyBeginLoc, LParenOrBraceLoc,
1463  RParenOrBraceLoc)
1464  : InitializationKind::CreateValue(TyBeginLoc, LParenOrBraceLoc,
1465  RParenOrBraceLoc);
1466 
1467  // C++1z [expr.type.conv]p1:
1468  // If the type is a placeholder for a deduced class type, [...perform class
1469  // template argument deduction...]
1470  DeducedType *Deduced = Ty->getContainedDeducedType();
1471  if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
1473  Kind, Exprs);
1474  if (Ty.isNull())
1475  return ExprError();
1476  Entity = InitializedEntity::InitializeTemporary(TInfo, Ty);
1477  }
1478 
1480  // FIXME: CXXUnresolvedConstructExpr does not model list-initialization
1481  // directly. We work around this by dropping the locations of the braces.
1482  SourceRange Locs = ListInitialization
1483  ? SourceRange()
1484  : SourceRange(LParenOrBraceLoc, RParenOrBraceLoc);
1486  TInfo, Locs.getBegin(), Exprs,
1487  Locs.getEnd());
1488  }
1489 
1490  // C++ [expr.type.conv]p1:
1491  // If the expression list is a parenthesized single expression, the type
1492  // conversion expression is equivalent (in definedness, and if defined in
1493  // meaning) to the corresponding cast expression.
1494  if (Exprs.size() == 1 && !ListInitialization &&
1495  !isa<InitListExpr>(Exprs[0])) {
1496  Expr *Arg = Exprs[0];
1497  return BuildCXXFunctionalCastExpr(TInfo, Ty, LParenOrBraceLoc, Arg,
1498  RParenOrBraceLoc);
1499  }
1500 
1501  // For an expression of the form T(), T shall not be an array type.
1502  QualType ElemTy = Ty;
1503  if (Ty->isArrayType()) {
1504  if (!ListInitialization)
1505  return ExprError(Diag(TyBeginLoc, diag::err_value_init_for_array_type)
1506  << FullRange);
1507  ElemTy = Context.getBaseElementType(Ty);
1508  }
1509 
1510  // Only construct objects with object types.
1511  // The standard doesn't explicitly forbid function types here, but that's an
1512  // obvious oversight, as there's no way to dynamically construct a function
1513  // in general.
1514  if (Ty->isFunctionType())
1515  return ExprError(Diag(TyBeginLoc, diag::err_init_for_function_type)
1516  << Ty << FullRange);
1517 
1518  // C++17 [expr.type.conv]p2:
1519  // If the type is cv void and the initializer is (), the expression is a
1520  // prvalue of the specified type that performs no initialization.
1521  if (!Ty->isVoidType() &&
1522  RequireCompleteType(TyBeginLoc, ElemTy,
1523  diag::err_invalid_incomplete_type_use, FullRange))
1524  return ExprError();
1525 
1526  // Otherwise, the expression is a prvalue of the specified type whose
1527  // result object is direct-initialized (11.6) with the initializer.
1528  InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
1529  ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Exprs);
1530 
1531  if (Result.isInvalid())
1532  return Result;
1533 
1534  Expr *Inner = Result.get();
1535  if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Inner))
1536  Inner = BTE->getSubExpr();
1537  if (!isa<CXXTemporaryObjectExpr>(Inner) &&
1538  !isa<CXXScalarValueInitExpr>(Inner)) {
1539  // If we created a CXXTemporaryObjectExpr, that node also represents the
1540  // functional cast. Otherwise, create an explicit cast to represent
1541  // the syntactic form of a functional-style cast that was used here.
1542  //
1543  // FIXME: Creating a CXXFunctionalCastExpr around a CXXConstructExpr
1544  // would give a more consistent AST representation than using a
1545  // CXXTemporaryObjectExpr. It's also weird that the functional cast
1546  // is sometimes handled by initialization and sometimes not.
1547  QualType ResultType = Result.get()->getType();
1548  SourceRange Locs = ListInitialization
1549  ? SourceRange()
1550  : SourceRange(LParenOrBraceLoc, RParenOrBraceLoc);
1552  Context, ResultType, Expr::getValueKindForType(Ty), TInfo, CK_NoOp,
1553  Result.get(), /*Path=*/nullptr, CurFPFeatureOverrides(),
1554  Locs.getBegin(), Locs.getEnd());
1555  }
1556 
1557  return Result;
1558 }
1559 
1561  // [CUDA] Ignore this function, if we can't call it.
1562  const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext);
1563  if (getLangOpts().CUDA) {
1564  auto CallPreference = IdentifyCUDAPreference(Caller, Method);
1565  // If it's not callable at all, it's not the right function.
1566  if (CallPreference < CFP_WrongSide)
1567  return false;
1568  if (CallPreference == CFP_WrongSide) {
1569  // Maybe. We have to check if there are better alternatives.
1571  Method->getDeclContext()->lookup(Method->getDeclName());
1572  for (const auto *D : R) {
1573  if (const auto *FD = dyn_cast<FunctionDecl>(D)) {
1574  if (IdentifyCUDAPreference(Caller, FD) > CFP_WrongSide)
1575  return false;
1576  }
1577  }
1578  // We've found no better variants.
1579  }
1580  }
1581 
1583  bool Result = Method->isUsualDeallocationFunction(PreventedBy);
1584 
1585  if (Result || !getLangOpts().CUDA || PreventedBy.empty())
1586  return Result;
1587 
1588  // In case of CUDA, return true if none of the 1-argument deallocator
1589  // functions are actually callable.
1590  return llvm::none_of(PreventedBy, [&](const FunctionDecl *FD) {
1591  assert(FD->getNumParams() == 1 &&
1592  "Only single-operand functions should be in PreventedBy");
1593  return IdentifyCUDAPreference(Caller, FD) >= CFP_HostDevice;
1594  });
1595 }
1596 
1597 /// Determine whether the given function is a non-placement
1598 /// deallocation function.
1600  if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD))
1601  return S.isUsualDeallocationFunction(Method);
1602 
1603  if (FD->getOverloadedOperator() != OO_Delete &&
1604  FD->getOverloadedOperator() != OO_Array_Delete)
1605  return false;
1606 
1607  unsigned UsualParams = 1;
1608 
1609  if (S.getLangOpts().SizedDeallocation && UsualParams < FD->getNumParams() &&
1611  FD->getParamDecl(UsualParams)->getType(),
1612  S.Context.getSizeType()))
1613  ++UsualParams;
1614 
1615  if (S.getLangOpts().AlignedAllocation && UsualParams < FD->getNumParams() &&
1617  FD->getParamDecl(UsualParams)->getType(),
1619  ++UsualParams;
1620 
1621  return UsualParams == FD->getNumParams();
1622 }
1623 
1624 namespace {
1625  struct UsualDeallocFnInfo {
1626  UsualDeallocFnInfo() : Found(), FD(nullptr) {}
1627  UsualDeallocFnInfo(Sema &S, DeclAccessPair Found)
1628  : Found(Found), FD(dyn_cast<FunctionDecl>(Found->getUnderlyingDecl())),
1629  Destroying(false), HasSizeT(false), HasAlignValT(false),
1630  CUDAPref(Sema::CFP_Native) {
1631  // A function template declaration is never a usual deallocation function.
1632  if (!FD)
1633  return;
1634  unsigned NumBaseParams = 1;
1635  if (FD->isDestroyingOperatorDelete()) {
1636  Destroying = true;
1637  ++NumBaseParams;
1638  }
1639 
1640  if (NumBaseParams < FD->getNumParams() &&
1642  FD->getParamDecl(NumBaseParams)->getType(),
1643  S.Context.getSizeType())) {
1644  ++NumBaseParams;
1645  HasSizeT = true;
1646  }
1647 
1648  if (NumBaseParams < FD->getNumParams() &&
1649  FD->getParamDecl(NumBaseParams)->getType()->isAlignValT()) {
1650  ++NumBaseParams;
1651  HasAlignValT = true;
1652  }
1653 
1654  // In CUDA, determine how much we'd like / dislike to call this.
1655  if (S.getLangOpts().CUDA)
1656  if (auto *Caller = dyn_cast<FunctionDecl>(S.CurContext))
1657  CUDAPref = S.IdentifyCUDAPreference(Caller, FD);
1658  }
1659 
1660  explicit operator bool() const { return FD; }
1661 
1662  bool isBetterThan(const UsualDeallocFnInfo &Other, bool WantSize,
1663  bool WantAlign) const {
1664  // C++ P0722:
1665  // A destroying operator delete is preferred over a non-destroying
1666  // operator delete.
1667  if (Destroying != Other.Destroying)
1668  return Destroying;
1669 
1670  // C++17 [expr.delete]p10:
1671  // If the type has new-extended alignment, a function with a parameter
1672  // of type std::align_val_t is preferred; otherwise a function without
1673  // such a parameter is preferred
1674  if (HasAlignValT != Other.HasAlignValT)
1675  return HasAlignValT == WantAlign;
1676 
1677  if (HasSizeT != Other.HasSizeT)
1678  return HasSizeT == WantSize;
1679 
1680  // Use CUDA call preference as a tiebreaker.
1681  return CUDAPref > Other.CUDAPref;
1682  }
1683 
1684  DeclAccessPair Found;
1685  FunctionDecl *FD;
1686  bool Destroying, HasSizeT, HasAlignValT;
1688  };
1689 }
1690 
1691 /// Determine whether a type has new-extended alignment. This may be called when
1692 /// the type is incomplete (for a delete-expression with an incomplete pointee
1693 /// type), in which case it will conservatively return false if the alignment is
1694 /// not known.
1695 static bool hasNewExtendedAlignment(Sema &S, QualType AllocType) {
1696  return S.getLangOpts().AlignedAllocation &&
1697  S.getASTContext().getTypeAlignIfKnown(AllocType) >
1699 }
1700 
1701 /// Select the correct "usual" deallocation function to use from a selection of
1702 /// deallocation functions (either global or class-scope).
1703 static UsualDeallocFnInfo resolveDeallocationOverload(
1704  Sema &S, LookupResult &R, bool WantSize, bool WantAlign,
1705  llvm::SmallVectorImpl<UsualDeallocFnInfo> *BestFns = nullptr) {
1706  UsualDeallocFnInfo Best;
1707 
1708  for (auto I = R.begin(), E = R.end(); I != E; ++I) {
1709  UsualDeallocFnInfo Info(S, I.getPair());
1710  if (!Info || !isNonPlacementDeallocationFunction(S, Info.FD) ||
1711  Info.CUDAPref == Sema::CFP_Never)
1712  continue;
1713 
1714  if (!Best) {
1715  Best = Info;
1716  if (BestFns)
1717  BestFns->push_back(Info);
1718  continue;
1719  }
1720 
1721  if (Best.isBetterThan(Info, WantSize, WantAlign))
1722  continue;
1723 
1724  // If more than one preferred function is found, all non-preferred
1725  // functions are eliminated from further consideration.
1726  if (BestFns && Info.isBetterThan(Best, WantSize, WantAlign))
1727  BestFns->clear();
1728 
1729  Best = Info;
1730  if (BestFns)
1731  BestFns->push_back(Info);
1732  }
1733 
1734  return Best;
1735 }
1736 
1737 /// Determine whether a given type is a class for which 'delete[]' would call
1738 /// a member 'operator delete[]' with a 'size_t' parameter. This implies that
1739 /// we need to store the array size (even if the type is
1740 /// trivially-destructible).
1742  QualType allocType) {
1743  const RecordType *record =
1744  allocType->getBaseElementTypeUnsafe()->getAs<RecordType>();
1745  if (!record) return false;
1746 
1747  // Try to find an operator delete[] in class scope.
1748 
1749  DeclarationName deleteName =
1750  S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete);
1751  LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName);
1752  S.LookupQualifiedName(ops, record->getDecl());
1753 
1754  // We're just doing this for information.
1755  ops.suppressDiagnostics();
1756 
1757  // Very likely: there's no operator delete[].
1758  if (ops.empty()) return false;
1759 
1760  // If it's ambiguous, it should be illegal to call operator delete[]
1761  // on this thing, so it doesn't matter if we allocate extra space or not.
1762  if (ops.isAmbiguous()) return false;
1763 
1764  // C++17 [expr.delete]p10:
1765  // If the deallocation functions have class scope, the one without a
1766  // parameter of type std::size_t is selected.
1767  auto Best = resolveDeallocationOverload(
1768  S, ops, /*WantSize*/false,
1769  /*WantAlign*/hasNewExtendedAlignment(S, allocType));
1770  return Best && Best.HasSizeT;
1771 }
1772 
1773 /// Parsed a C++ 'new' expression (C++ 5.3.4).
1774 ///
1775 /// E.g.:
1776 /// @code new (memory) int[size][4] @endcode
1777 /// or
1778 /// @code ::new Foo(23, "hello") @endcode
1779 ///
1780 /// \param StartLoc The first location of the expression.
1781 /// \param UseGlobal True if 'new' was prefixed with '::'.
1782 /// \param PlacementLParen Opening paren of the placement arguments.
1783 /// \param PlacementArgs Placement new arguments.
1784 /// \param PlacementRParen Closing paren of the placement arguments.
1785 /// \param TypeIdParens If the type is in parens, the source range.
1786 /// \param D The type to be allocated, as well as array dimensions.
1787 /// \param Initializer The initializing expression or initializer-list, or null
1788 /// if there is none.
1789 ExprResult
1790 Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
1791  SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
1792  SourceLocation PlacementRParen, SourceRange TypeIdParens,
1793  Declarator &D, Expr *Initializer) {
1794  Optional<Expr *> ArraySize;
1795  // If the specified type is an array, unwrap it and save the expression.
1796  if (D.getNumTypeObjects() > 0 &&
1798  DeclaratorChunk &Chunk = D.getTypeObject(0);
1799  if (D.getDeclSpec().hasAutoTypeSpec())
1800  return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto)
1801  << D.getSourceRange());
1802  if (Chunk.Arr.hasStatic)
1803  return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
1804  << D.getSourceRange());
1805  if (!Chunk.Arr.NumElts && !Initializer)
1806  return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
1807  << D.getSourceRange());
1808 
1809  ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
1810  D.DropFirstTypeObject();
1811  }
1812 
1813  // Every dimension shall be of constant size.
1814  if (ArraySize) {
1815  for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
1817  break;
1818 
1820  if (Expr *NumElts = (Expr *)Array.NumElts) {
1821  if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
1822  // FIXME: GCC permits constant folding here. We should either do so consistently
1823  // or not do so at all, rather than changing behavior in C++14 onwards.
1824  if (getLangOpts().CPlusPlus14) {
1825  // C++1y [expr.new]p6: Every constant-expression in a noptr-new-declarator
1826  // shall be a converted constant expression (5.19) of type std::size_t
1827  // and shall evaluate to a strictly positive value.
1829  Array.NumElts
1832  .get();
1833  } else {
1834  Array.NumElts =
1836  NumElts, nullptr, diag::err_new_array_nonconst, AllowFold)
1837  .get();
1838  }
1839  if (!Array.NumElts)
1840  return ExprError();
1841  }
1842  }
1843  }
1844  }
1845 
1846  TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/nullptr);
1847  QualType AllocType = TInfo->getType();
1848  if (D.isInvalidType())
1849  return ExprError();
1850 
1851  SourceRange DirectInitRange;
1852  if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer))
1853  DirectInitRange = List->getSourceRange();
1854 
1855  return BuildCXXNew(SourceRange(StartLoc, D.getEndLoc()), UseGlobal,
1856  PlacementLParen, PlacementArgs, PlacementRParen,
1857  TypeIdParens, AllocType, TInfo, ArraySize, DirectInitRange,
1858  Initializer);
1859 }
1860 
1862  Expr *Init) {
1863  if (!Init)
1864  return true;
1865  if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init))
1866  return PLE->getNumExprs() == 0;
1867  if (isa<ImplicitValueInitExpr>(Init))
1868  return true;
1869  else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init))
1870  return !CCE->isListInitialization() &&
1871  CCE->getConstructor()->isDefaultConstructor();
1872  else if (Style == CXXNewExpr::ListInit) {
1873  assert(isa<InitListExpr>(Init) &&
1874  "Shouldn't create list CXXConstructExprs for arrays.");
1875  return true;
1876  }
1877  return false;
1878 }
1879 
1880 bool
1882  if (!getLangOpts().AlignedAllocationUnavailable)
1883  return false;
1884  if (FD.isDefined())
1885  return false;
1886  Optional<unsigned> AlignmentParam;
1887  if (FD.isReplaceableGlobalAllocationFunction(&AlignmentParam) &&
1888  AlignmentParam.hasValue())
1889  return true;
1890  return false;
1891 }
1892 
1893 // Emit a diagnostic if an aligned allocation/deallocation function that is not
1894 // implemented in the standard library is selected.
1896  SourceLocation Loc) {
1898  const llvm::Triple &T = getASTContext().getTargetInfo().getTriple();
1899  StringRef OSName = AvailabilityAttr::getPlatformNameSourceSpelling(
1900  getASTContext().getTargetInfo().getPlatformName());
1901  VersionTuple OSVersion = alignedAllocMinVersion(T.getOS());
1902 
1904  bool IsDelete = Kind == OO_Delete || Kind == OO_Array_Delete;
1905  Diag(Loc, diag::err_aligned_allocation_unavailable)
1906  << IsDelete << FD.getType().getAsString() << OSName
1907  << OSVersion.getAsString() << OSVersion.empty();
1908  Diag(Loc, diag::note_silence_aligned_allocation_unavailable);
1909  }
1910 }
1911 
1912 ExprResult
1913 Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
1914  SourceLocation PlacementLParen,
1915  MultiExprArg PlacementArgs,
1916  SourceLocation PlacementRParen,
1917  SourceRange TypeIdParens,
1918  QualType AllocType,
1919  TypeSourceInfo *AllocTypeInfo,
1920  Optional<Expr *> ArraySize,
1921  SourceRange DirectInitRange,
1922  Expr *Initializer) {
1923  SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange();
1924  SourceLocation StartLoc = Range.getBegin();
1925 
1927  if (DirectInitRange.isValid()) {
1928  assert(Initializer && "Have parens but no initializer.");
1929  initStyle = CXXNewExpr::CallInit;
1930  } else if (Initializer && isa<InitListExpr>(Initializer))
1931  initStyle = CXXNewExpr::ListInit;
1932  else {
1933  assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) ||
1934  isa<CXXConstructExpr>(Initializer)) &&
1935  "Initializer expression that cannot have been implicitly created.");
1936  initStyle = CXXNewExpr::NoInit;
1937  }
1938 
1939  Expr **Inits = &Initializer;
1940  unsigned NumInits = Initializer ? 1 : 0;
1941  if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) {
1942  assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init");
1943  Inits = List->getExprs();
1944  NumInits = List->getNumExprs();
1945  }
1946 
1947  // C++11 [expr.new]p15:
1948  // A new-expression that creates an object of type T initializes that
1949  // object as follows:
1951  // - If the new-initializer is omitted, the object is default-
1952  // initialized (8.5); if no initialization is performed,
1953  // the object has indeterminate value
1954  = initStyle == CXXNewExpr::NoInit
1956  // - Otherwise, the new-initializer is interpreted according to
1957  // the
1958  // initialization rules of 8.5 for direct-initialization.
1959  : initStyle == CXXNewExpr::ListInit
1961  TypeRange.getBegin(), Initializer->getBeginLoc(),
1962  Initializer->getEndLoc())
1964  DirectInitRange.getBegin(),
1965  DirectInitRange.getEnd());
1966 
1967  // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
1968  auto *Deduced = AllocType->getContainedDeducedType();
1969  if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
1970  if (ArraySize)
1971  return ExprError(
1972  Diag(*ArraySize ? (*ArraySize)->getExprLoc() : TypeRange.getBegin(),
1973  diag::err_deduced_class_template_compound_type)
1974  << /*array*/ 2
1975  << (*ArraySize ? (*ArraySize)->getSourceRange() : TypeRange));
1976 
1977  InitializedEntity Entity
1978  = InitializedEntity::InitializeNew(StartLoc, AllocType);
1980  AllocTypeInfo, Entity, Kind, MultiExprArg(Inits, NumInits));
1981  if (AllocType.isNull())
1982  return ExprError();
1983  } else if (Deduced) {
1984  bool Braced = (initStyle == CXXNewExpr::ListInit);
1985  if (NumInits == 1) {
1986  if (auto p = dyn_cast_or_null<InitListExpr>(Inits[0])) {
1987  Inits = p->getInits();
1988  NumInits = p->getNumInits();
1989  Braced = true;
1990  }
1991  }
1992 
1993  if (initStyle == CXXNewExpr::NoInit || NumInits == 0)
1994  return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg)
1995  << AllocType << TypeRange);
1996  if (NumInits > 1) {
1997  Expr *FirstBad = Inits[1];
1998  return ExprError(Diag(FirstBad->getBeginLoc(),
1999  diag::err_auto_new_ctor_multiple_expressions)
2000  << AllocType << TypeRange);
2001  }
2002  if (Braced && !getLangOpts().CPlusPlus17)
2003  Diag(Initializer->getBeginLoc(), diag::ext_auto_new_list_init)
2004  << AllocType << TypeRange;
2005  Expr *Deduce = Inits[0];
2007  if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed)
2008  return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure)
2009  << AllocType << Deduce->getType()
2010  << TypeRange << Deduce->getSourceRange());
2011  if (DeducedType.isNull())
2012  return ExprError();
2013  AllocType = DeducedType;
2014  }
2015 
2016  // Per C++0x [expr.new]p5, the type being constructed may be a
2017  // typedef of an array type.
2018  if (!ArraySize) {
2019  if (const ConstantArrayType *Array
2020  = Context.getAsConstantArrayType(AllocType)) {
2021  ArraySize = IntegerLiteral::Create(Context, Array->getSize(),
2022  Context.getSizeType(),
2023  TypeRange.getEnd());
2024  AllocType = Array->getElementType();
2025  }
2026  }
2027 
2028  if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange))
2029  return ExprError();
2030 
2031  // In ARC, infer 'retaining' for the allocated
2032  if (getLangOpts().ObjCAutoRefCount &&
2033  AllocType.getObjCLifetime() == Qualifiers::OCL_None &&
2034  AllocType->isObjCLifetimeType()) {
2035  AllocType = Context.getLifetimeQualifiedType(AllocType,
2036  AllocType->getObjCARCImplicitLifetime());
2037  }
2038 
2039  QualType ResultType = Context.getPointerType(AllocType);
2040 
2041  if (ArraySize && *ArraySize &&
2042  (*ArraySize)->getType()->isNonOverloadPlaceholderType()) {
2043  ExprResult result = CheckPlaceholderExpr(*ArraySize);
2044  if (result.isInvalid()) return ExprError();
2045  ArraySize = result.get();
2046  }
2047  // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have
2048  // integral or enumeration type with a non-negative value."
2049  // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped
2050  // enumeration type, or a class type for which a single non-explicit
2051  // conversion function to integral or unscoped enumeration type exists.
2052  // C++1y [expr.new]p6: The expression [...] is implicitly converted to
2053  // std::size_t.
2054  llvm::Optional<uint64_t> KnownArraySize;
2055  if (ArraySize && *ArraySize && !(*ArraySize)->isTypeDependent()) {
2056  ExprResult ConvertedSize;
2057  if (getLangOpts().CPlusPlus14) {
2058  assert(Context.getTargetInfo().getIntWidth() && "Builtin type of size 0?");
2059 
2060  ConvertedSize = PerformImplicitConversion(*ArraySize, Context.getSizeType(),
2061  AA_Converting);
2062 
2063  if (!ConvertedSize.isInvalid() &&
2064  (*ArraySize)->getType()->getAs<RecordType>())
2065  // Diagnose the compatibility of this conversion.
2066  Diag(StartLoc, diag::warn_cxx98_compat_array_size_conversion)
2067  << (*ArraySize)->getType() << 0 << "'size_t'";
2068  } else {
2069  class SizeConvertDiagnoser : public ICEConvertDiagnoser {
2070  protected:
2071  Expr *ArraySize;
2072 
2073  public:
2074  SizeConvertDiagnoser(Expr *ArraySize)
2075  : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false, false, false),
2076  ArraySize(ArraySize) {}
2077 
2078  SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
2079  QualType T) override {
2080  return S.Diag(Loc, diag::err_array_size_not_integral)
2081  << S.getLangOpts().CPlusPlus11 << T;
2082  }
2083 
2084  SemaDiagnosticBuilder diagnoseIncomplete(
2085  Sema &S, SourceLocation Loc, QualType T) override {
2086  return S.Diag(Loc, diag::err_array_size_incomplete_type)
2087  << T << ArraySize->getSourceRange();
2088  }
2089 
2090  SemaDiagnosticBuilder diagnoseExplicitConv(
2091  Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
2092  return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy;
2093  }
2094 
2095  SemaDiagnosticBuilder noteExplicitConv(
2096  Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
2097  return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
2098  << ConvTy->isEnumeralType() << ConvTy;
2099  }
2100 
2101  SemaDiagnosticBuilder diagnoseAmbiguous(
2102  Sema &S, SourceLocation Loc, QualType T) override {
2103  return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T;
2104  }
2105 
2106  SemaDiagnosticBuilder noteAmbiguous(
2107  Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
2108  return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
2109  << ConvTy->isEnumeralType() << ConvTy;
2110  }
2111 
2112  SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
2113  QualType T,
2114  QualType ConvTy) override {
2115  return S.Diag(Loc,
2116  S.getLangOpts().CPlusPlus11
2117  ? diag::warn_cxx98_compat_array_size_conversion
2118  : diag::ext_array_size_conversion)
2119  << T << ConvTy->isEnumeralType() << ConvTy;
2120  }
2121  } SizeDiagnoser(*ArraySize);
2122 
2123  ConvertedSize = PerformContextualImplicitConversion(StartLoc, *ArraySize,
2124  SizeDiagnoser);
2125  }
2126  if (ConvertedSize.isInvalid())
2127  return ExprError();
2128 
2129  ArraySize = ConvertedSize.get();
2130  QualType SizeType = (*ArraySize)->getType();
2131 
2132  if (!SizeType->isIntegralOrUnscopedEnumerationType())
2133  return ExprError();
2134 
2135  // C++98 [expr.new]p7:
2136  // The expression in a direct-new-declarator shall have integral type
2137  // with a non-negative value.
2138  //
2139  // Let's see if this is a constant < 0. If so, we reject it out of hand,
2140  // per CWG1464. Otherwise, if it's not a constant, we must have an
2141  // unparenthesized array type.
2142 
2143  // We've already performed any required implicit conversion to integer or
2144  // unscoped enumeration type.
2145  // FIXME: Per CWG1464, we are required to check the value prior to
2146  // converting to size_t. This will never find a negative array size in
2147  // C++14 onwards, because Value is always unsigned here!
2149  (*ArraySize)->getIntegerConstantExpr(Context)) {
2150  if (Value->isSigned() && Value->isNegative()) {
2151  return ExprError(Diag((*ArraySize)->getBeginLoc(),
2152  diag::err_typecheck_negative_array_size)
2153  << (*ArraySize)->getSourceRange());
2154  }
2155 
2156  if (!AllocType->isDependentType()) {
2157  unsigned ActiveSizeBits =
2159  if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context))
2160  return ExprError(
2161  Diag((*ArraySize)->getBeginLoc(), diag::err_array_too_large)
2162  << toString(*Value, 10) << (*ArraySize)->getSourceRange());
2163  }
2164 
2165  KnownArraySize = Value->getZExtValue();
2166  } else if (TypeIdParens.isValid()) {
2167  // Can't have dynamic array size when the type-id is in parentheses.
2168  Diag((*ArraySize)->getBeginLoc(), diag::ext_new_paren_array_nonconst)
2169  << (*ArraySize)->getSourceRange()
2170  << FixItHint::CreateRemoval(TypeIdParens.getBegin())
2171  << FixItHint::CreateRemoval(TypeIdParens.getEnd());
2172 
2173  TypeIdParens = SourceRange();
2174  }
2175 
2176  // Note that we do *not* convert the argument in any way. It can
2177  // be signed, larger than size_t, whatever.
2178  }
2179 
2180  FunctionDecl *OperatorNew = nullptr;
2181  FunctionDecl *OperatorDelete = nullptr;
2182  unsigned Alignment =
2183  AllocType->isDependentType() ? 0 : Context.getTypeAlign(AllocType);
2184  unsigned NewAlignment = Context.getTargetInfo().getNewAlign();
2185  bool PassAlignment = getLangOpts().AlignedAllocation &&
2186  Alignment > NewAlignment;
2187 
2189  if (!AllocType->isDependentType() &&
2190  !Expr::hasAnyTypeDependentArguments(PlacementArgs) &&
2192  StartLoc, SourceRange(PlacementLParen, PlacementRParen), Scope, Scope,
2193  AllocType, ArraySize.hasValue(), PassAlignment, PlacementArgs,
2194  OperatorNew, OperatorDelete))
2195  return ExprError();
2196 
2197  // If this is an array allocation, compute whether the usual array
2198  // deallocation function for the type has a size_t parameter.
2199  bool UsualArrayDeleteWantsSize = false;
2200  if (ArraySize && !AllocType->isDependentType())
2201  UsualArrayDeleteWantsSize =
2202  doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType);
2203 
2204  SmallVector<Expr *, 8> AllPlaceArgs;
2205  if (OperatorNew) {
2206  auto *Proto = OperatorNew->getType()->castAs<FunctionProtoType>();
2207  VariadicCallType CallType = Proto->isVariadic() ? VariadicFunction
2209 
2210  // We've already converted the placement args, just fill in any default
2211  // arguments. Skip the first parameter because we don't have a corresponding
2212  // argument. Skip the second parameter too if we're passing in the
2213  // alignment; we've already filled it in.
2214  unsigned NumImplicitArgs = PassAlignment ? 2 : 1;
2215  if (GatherArgumentsForCall(PlacementLParen, OperatorNew, Proto,
2216  NumImplicitArgs, PlacementArgs, AllPlaceArgs,
2217  CallType))
2218  return ExprError();
2219 
2220  if (!AllPlaceArgs.empty())
2221  PlacementArgs = AllPlaceArgs;
2222 
2223  // We would like to perform some checking on the given `operator new` call,
2224  // but the PlacementArgs does not contain the implicit arguments,
2225  // namely allocation size and maybe allocation alignment,
2226  // so we need to conjure them.
2227 
2228  QualType SizeTy = Context.getSizeType();
2229  unsigned SizeTyWidth = Context.getTypeSize(SizeTy);
2230 
2231  llvm::APInt SingleEltSize(
2232  SizeTyWidth, Context.getTypeSizeInChars(AllocType).getQuantity());
2233 
2234  // How many bytes do we want to allocate here?
2235  llvm::Optional<llvm::APInt> AllocationSize;
2236  if (!ArraySize.hasValue() && !AllocType->isDependentType()) {
2237  // For non-array operator new, we only want to allocate one element.
2238  AllocationSize = SingleEltSize;
2239  } else if (KnownArraySize.hasValue() && !AllocType->isDependentType()) {
2240  // For array operator new, only deal with static array size case.
2241  bool Overflow;
2242  AllocationSize = llvm::APInt(SizeTyWidth, *KnownArraySize)
2243  .umul_ov(SingleEltSize, Overflow);
2244  (void)Overflow;
2245  assert(
2246  !Overflow &&
2247  "Expected that all the overflows would have been handled already.");
2248  }
2249 
2250  IntegerLiteral AllocationSizeLiteral(
2251  Context, AllocationSize.getValueOr(llvm::APInt::getZero(SizeTyWidth)),
2252  SizeTy, SourceLocation());
2253  // Otherwise, if we failed to constant-fold the allocation size, we'll
2254  // just give up and pass-in something opaque, that isn't a null pointer.
2255  OpaqueValueExpr OpaqueAllocationSize(SourceLocation(), SizeTy, VK_PRValue,
2256  OK_Ordinary, /*SourceExpr=*/nullptr);
2257 
2258  // Let's synthesize the alignment argument in case we will need it.
2259  // Since we *really* want to allocate these on stack, this is slightly ugly
2260  // because there might not be a `std::align_val_t` type.
2262  QualType AlignValT =
2264  IntegerLiteral AlignmentLiteral(
2265  Context,
2267  Alignment / Context.getCharWidth()),
2268  SizeTy, SourceLocation());
2269  ImplicitCastExpr DesiredAlignment(ImplicitCastExpr::OnStack, AlignValT,
2270  CK_IntegralCast, &AlignmentLiteral,
2272 
2273  // Adjust placement args by prepending conjured size and alignment exprs.
2275  CallArgs.reserve(NumImplicitArgs + PlacementArgs.size());
2276  CallArgs.emplace_back(AllocationSize.hasValue()
2277  ? static_cast<Expr *>(&AllocationSizeLiteral)
2278  : &OpaqueAllocationSize);
2279  if (PassAlignment)
2280  CallArgs.emplace_back(&DesiredAlignment);
2281  CallArgs.insert(CallArgs.end(), PlacementArgs.begin(), PlacementArgs.end());
2282 
2283  DiagnoseSentinelCalls(OperatorNew, PlacementLParen, CallArgs);
2284 
2285  checkCall(OperatorNew, Proto, /*ThisArg=*/nullptr, CallArgs,
2286  /*IsMemberFunction=*/false, StartLoc, Range, CallType);
2287 
2288  // Warn if the type is over-aligned and is being allocated by (unaligned)
2289  // global operator new.
2290  if (PlacementArgs.empty() && !PassAlignment &&
2291  (OperatorNew->isImplicit() ||
2292  (OperatorNew->getBeginLoc().isValid() &&
2293  getSourceManager().isInSystemHeader(OperatorNew->getBeginLoc())))) {
2294  if (Alignment > NewAlignment)
2295  Diag(StartLoc, diag::warn_overaligned_type)
2296  << AllocType
2297  << unsigned(Alignment / Context.getCharWidth())
2298  << unsigned(NewAlignment / Context.getCharWidth());
2299  }
2300  }
2301 
2302  // Array 'new' can't have any initializers except empty parentheses.
2303  // Initializer lists are also allowed, in C++11. Rely on the parser for the
2304  // dialect distinction.
2305  if (ArraySize && !isLegalArrayNewInitializer(initStyle, Initializer)) {
2306  SourceRange InitRange(Inits[0]->getBeginLoc(),
2307  Inits[NumInits - 1]->getEndLoc());
2308  Diag(StartLoc, diag::err_new_array_init_args) << InitRange;
2309  return ExprError();
2310  }
2311 
2312  // If we can perform the initialization, and we've not already done so,
2313  // do it now.
2314  if (!AllocType->isDependentType() &&
2316  llvm::makeArrayRef(Inits, NumInits))) {
2317  // The type we initialize is the complete type, including the array bound.
2318  QualType InitType;
2319  if (KnownArraySize)
2320  InitType = Context.getConstantArrayType(
2321  AllocType,
2323  *KnownArraySize),
2324  *ArraySize, ArrayType::Normal, 0);
2325  else if (ArraySize)
2326  InitType =
2328  else
2329  InitType = AllocType;
2330 
2331  InitializedEntity Entity
2332  = InitializedEntity::InitializeNew(StartLoc, InitType);
2333  InitializationSequence InitSeq(*this, Entity, Kind,
2334  MultiExprArg(Inits, NumInits));
2335  ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind,
2336  MultiExprArg(Inits, NumInits));
2337  if (FullInit.isInvalid())
2338  return ExprError();
2339 
2340  // FullInit is our initializer; strip off CXXBindTemporaryExprs, because
2341  // we don't want the initialized object to be destructed.
2342  // FIXME: We should not create these in the first place.
2343  if (CXXBindTemporaryExpr *Binder =
2344  dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get()))
2345  FullInit = Binder->getSubExpr();
2346 
2347  Initializer = FullInit.get();
2348 
2349  // FIXME: If we have a KnownArraySize, check that the array bound of the
2350  // initializer is no greater than that constant value.
2351 
2352  if (ArraySize && !*ArraySize) {
2353  auto *CAT = Context.getAsConstantArrayType(Initializer->getType());
2354  if (CAT) {
2355  // FIXME: Track that the array size was inferred rather than explicitly
2356  // specified.
2357  ArraySize = IntegerLiteral::Create(
2358  Context, CAT->getSize(), Context.getSizeType(), TypeRange.getEnd());
2359  } else {
2360  Diag(TypeRange.getEnd(), diag::err_new_array_size_unknown_from_init)
2361  << Initializer->getSourceRange();
2362  }
2363  }
2364  }
2365 
2366  // Mark the new and delete operators as referenced.
2367  if (OperatorNew) {
2368  if (DiagnoseUseOfDecl(OperatorNew, StartLoc))
2369  return ExprError();
2370  MarkFunctionReferenced(StartLoc, OperatorNew);
2371  }
2372  if (OperatorDelete) {
2373  if (DiagnoseUseOfDecl(OperatorDelete, StartLoc))
2374  return ExprError();
2375  MarkFunctionReferenced(StartLoc, OperatorDelete);
2376  }
2377 
2378  return CXXNewExpr::Create(Context, UseGlobal, OperatorNew, OperatorDelete,
2379  PassAlignment, UsualArrayDeleteWantsSize,
2380  PlacementArgs, TypeIdParens, ArraySize, initStyle,
2381  Initializer, ResultType, AllocTypeInfo, Range,
2382  DirectInitRange);
2383 }
2384 
2385 /// Checks that a type is suitable as the allocated type
2386 /// in a new-expression.
2388  SourceRange R) {
2389  // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
2390  // abstract class type or array thereof.
2391  if (AllocType->isFunctionType())
2392  return Diag(Loc, diag::err_bad_new_type)
2393  << AllocType << 0 << R;
2394  else if (AllocType->isReferenceType())
2395  return Diag(Loc, diag::err_bad_new_type)
2396  << AllocType << 1 << R;
2397  else if (!AllocType->isDependentType() &&
2399  Loc, AllocType, diag::err_new_incomplete_or_sizeless_type, R))
2400  return true;
2401  else if (RequireNonAbstractType(Loc, AllocType,
2402  diag::err_allocation_of_abstract_type))
2403  return true;
2404  else if (AllocType->isVariablyModifiedType())
2405  return Diag(Loc, diag::err_variably_modified_new_type)
2406  << AllocType;
2407  else if (AllocType.getAddressSpace() != LangAS::Default &&
2408  !getLangOpts().OpenCLCPlusPlus)
2409  return Diag(Loc, diag::err_address_space_qualified_new)
2410  << AllocType.getUnqualifiedType()
2412  else if (getLangOpts().ObjCAutoRefCount) {
2413  if (const ArrayType *AT = Context.getAsArrayType(AllocType)) {
2414  QualType BaseAllocType = Context.getBaseElementType(AT);
2415  if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None &&
2416  BaseAllocType->isObjCLifetimeType())
2417  return Diag(Loc, diag::err_arc_new_array_without_ownership)
2418  << BaseAllocType;
2419  }
2420  }
2421 
2422  return false;
2423 }
2424 
2427  bool &PassAlignment, FunctionDecl *&Operator,
2428  OverloadCandidateSet *AlignedCandidates, Expr *AlignArg, bool Diagnose) {
2429  OverloadCandidateSet Candidates(R.getNameLoc(),
2431  for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
2432  Alloc != AllocEnd; ++Alloc) {
2433  // Even member operator new/delete are implicitly treated as
2434  // static, so don't use AddMemberCandidate.
2435  NamedDecl *D = (*Alloc)->getUnderlyingDecl();
2436 
2437  if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
2438  S.AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(),
2439  /*ExplicitTemplateArgs=*/nullptr, Args,
2440  Candidates,
2441  /*SuppressUserConversions=*/false);
2442  continue;
2443  }
2444 
2445  FunctionDecl *Fn = cast<FunctionDecl>(D);
2446  S.AddOverloadCandidate(Fn, Alloc.getPair(), Args, Candidates,
2447  /*SuppressUserConversions=*/false);
2448  }
2449 
2450  // Do the resolution.
2452  switch (Candidates.BestViableFunction(S, R.getNameLoc(), Best)) {
2453  case OR_Success: {
2454  // Got one!
2455  FunctionDecl *FnDecl = Best->Function;
2456  if (S.CheckAllocationAccess(R.getNameLoc(), Range, R.getNamingClass(),
2457  Best->FoundDecl) == Sema::AR_inaccessible)
2458  return true;
2459 
2460  Operator = FnDecl;
2461  return false;
2462  }
2463 
2464  case OR_No_Viable_Function:
2465  // C++17 [expr.new]p13:
2466  // If no matching function is found and the allocated object type has
2467  // new-extended alignment, the alignment argument is removed from the
2468  // argument list, and overload resolution is performed again.
2469  if (PassAlignment) {
2470  PassAlignment = false;
2471  AlignArg = Args[1];
2472  Args.erase(Args.begin() + 1);
2473  return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2474  Operator, &Candidates, AlignArg,
2475  Diagnose);
2476  }
2477 
2478  // MSVC will fall back on trying to find a matching global operator new
2479  // if operator new[] cannot be found. Also, MSVC will leak by not
2480  // generating a call to operator delete or operator delete[], but we
2481  // will not replicate that bug.
2482  // FIXME: Find out how this interacts with the std::align_val_t fallback
2483  // once MSVC implements it.
2484  if (R.getLookupName().getCXXOverloadedOperator() == OO_Array_New &&
2485  S.Context.getLangOpts().MSVCCompat) {
2486  R.clear();
2489  // FIXME: This will give bad diagnostics pointing at the wrong functions.
2490  return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2491  Operator, /*Candidates=*/nullptr,
2492  /*AlignArg=*/nullptr, Diagnose);
2493  }
2494 
2495  if (Diagnose) {
2496  // If this is an allocation of the form 'new (p) X' for some object
2497  // pointer p (or an expression that will decay to such a pointer),
2498  // diagnose the missing inclusion of <new>.
2499  if (!R.isClassLookup() && Args.size() == 2 &&
2500  (Args[1]->getType()->isObjectPointerType() ||
2501  Args[1]->getType()->isArrayType())) {
2502  S.Diag(R.getNameLoc(), diag::err_need_header_before_placement_new)
2503  << R.getLookupName() << Range;
2504  // Listing the candidates is unlikely to be useful; skip it.
2505  return true;
2506  }
2507 
2508  // Finish checking all candidates before we note any. This checking can
2509  // produce additional diagnostics so can't be interleaved with our
2510  // emission of notes.
2511  //
2512  // For an aligned allocation, separately check the aligned and unaligned
2513  // candidates with their respective argument lists.
2516  llvm::SmallVector<Expr*, 4> AlignedArgs;
2517  if (AlignedCandidates) {
2518  auto IsAligned = [](OverloadCandidate &C) {
2519  return C.Function->getNumParams() > 1 &&
2520  C.Function->getParamDecl(1)->getType()->isAlignValT();
2521  };
2522  auto IsUnaligned = [&](OverloadCandidate &C) { return !IsAligned(C); };
2523 
2524  AlignedArgs.reserve(Args.size() + 1);
2525  AlignedArgs.push_back(Args[0]);
2526  AlignedArgs.push_back(AlignArg);
2527  AlignedArgs.append(Args.begin() + 1, Args.end());
2528  AlignedCands = AlignedCandidates->CompleteCandidates(
2529  S, OCD_AllCandidates, AlignedArgs, R.getNameLoc(), IsAligned);
2530 
2531  Cands = Candidates.CompleteCandidates(S, OCD_AllCandidates, Args,
2532  R.getNameLoc(), IsUnaligned);
2533  } else {
2534  Cands = Candidates.CompleteCandidates(S, OCD_AllCandidates, Args,
2535  R.getNameLoc());
2536  }
2537 
2538  S.Diag(R.getNameLoc(), diag::err_ovl_no_viable_function_in_call)
2539  << R.getLookupName() << Range;
2540  if (AlignedCandidates)
2541  AlignedCandidates->NoteCandidates(S, AlignedArgs, AlignedCands, "",
2542  R.getNameLoc());
2543  Candidates.NoteCandidates(S, Args, Cands, "", R.getNameLoc());
2544  }
2545  return true;
2546 
2547  case OR_Ambiguous:
2548  if (Diagnose) {
2549  Candidates.NoteCandidates(
2551  S.PDiag(diag::err_ovl_ambiguous_call)
2552  << R.getLookupName() << Range),
2553  S, OCD_AmbiguousCandidates, Args);
2554  }
2555  return true;
2556 
2557  case OR_Deleted: {
2558  if (Diagnose) {
2559  Candidates.NoteCandidates(
2561  S.PDiag(diag::err_ovl_deleted_call)
2562  << R.getLookupName() << Range),
2563  S, OCD_AllCandidates, Args);
2564  }
2565  return true;
2566  }
2567  }
2568  llvm_unreachable("Unreachable, bad result from BestViableFunction");
2569 }
2570 
2572  AllocationFunctionScope NewScope,
2573  AllocationFunctionScope DeleteScope,
2574  QualType AllocType, bool IsArray,
2575  bool &PassAlignment, MultiExprArg PlaceArgs,
2576  FunctionDecl *&OperatorNew,
2577  FunctionDecl *&OperatorDelete,
2578  bool Diagnose) {
2579  // --- Choosing an allocation function ---
2580  // C++ 5.3.4p8 - 14 & 18
2581  // 1) If looking in AFS_Global scope for allocation functions, only look in
2582  // the global scope. Else, if AFS_Class, only look in the scope of the
2583  // allocated class. If AFS_Both, look in both.
2584  // 2) If an array size is given, look for operator new[], else look for
2585  // operator new.
2586  // 3) The first argument is always size_t. Append the arguments from the
2587  // placement form.
2588 
2589  SmallVector<Expr*, 8> AllocArgs;
2590  AllocArgs.reserve((PassAlignment ? 2 : 1) + PlaceArgs.size());
2591 
2592  // We don't care about the actual value of these arguments.
2593  // FIXME: Should the Sema create the expression and embed it in the syntax
2594  // tree? Or should the consumer just recalculate the value?
2595  // FIXME: Using a dummy value will interact poorly with attribute enable_if.
2596  IntegerLiteral Size(
2597  Context, llvm::APInt::getZero(Context.getTargetInfo().getPointerWidth(0)),
2599  AllocArgs.push_back(&Size);
2600 
2601  QualType AlignValT = Context.VoidTy;
2602  if (PassAlignment) {
2604  AlignValT = Context.getTypeDeclType(getStdAlignValT());
2605  }
2606  CXXScalarValueInitExpr Align(AlignValT, nullptr, SourceLocation());
2607  if (PassAlignment)
2608  AllocArgs.push_back(&Align);
2609 
2610  AllocArgs.insert(AllocArgs.end(), PlaceArgs.begin(), PlaceArgs.end());
2611 
2612  // C++ [expr.new]p8:
2613  // If the allocated type is a non-array type, the allocation
2614  // function's name is operator new and the deallocation function's
2615  // name is operator delete. If the allocated type is an array
2616  // type, the allocation function's name is operator new[] and the
2617  // deallocation function's name is operator delete[].
2619  IsArray ? OO_Array_New : OO_New);
2620 
2621  QualType AllocElemType = Context.getBaseElementType(AllocType);
2622 
2623  // Find the allocation function.
2624  {
2625  LookupResult R(*this, NewName, StartLoc, LookupOrdinaryName);
2626 
2627  // C++1z [expr.new]p9:
2628  // If the new-expression begins with a unary :: operator, the allocation
2629  // function's name is looked up in the global scope. Otherwise, if the
2630  // allocated type is a class type T or array thereof, the allocation
2631  // function's name is looked up in the scope of T.
2632  if (AllocElemType->isRecordType() && NewScope != AFS_Global)
2633  LookupQualifiedName(R, AllocElemType->getAsCXXRecordDecl());
2634 
2635  // We can see ambiguity here if the allocation function is found in
2636  // multiple base classes.
2637  if (R.isAmbiguous())
2638  return true;
2639 
2640  // If this lookup fails to find the name, or if the allocated type is not
2641  // a class type, the allocation function's name is looked up in the
2642  // global scope.
2643  if (R.empty()) {
2644  if (NewScope == AFS_Class)
2645  return true;
2646 
2648  }
2649 
2650  if (getLangOpts().OpenCLCPlusPlus && R.empty()) {
2651  if (PlaceArgs.empty()) {
2652  Diag(StartLoc, diag::err_openclcxx_not_supported) << "default new";
2653  } else {
2654  Diag(StartLoc, diag::err_openclcxx_placement_new);
2655  }
2656  return true;
2657  }
2658 
2659  assert(!R.empty() && "implicitly declared allocation functions not found");
2660  assert(!R.isAmbiguous() && "global allocation functions are ambiguous");
2661 
2662  // We do our own custom access checks below.
2663  R.suppressDiagnostics();
2664 
2665  if (resolveAllocationOverload(*this, R, Range, AllocArgs, PassAlignment,
2666  OperatorNew, /*Candidates=*/nullptr,
2667  /*AlignArg=*/nullptr, Diagnose))
2668  return true;
2669  }
2670 
2671  // We don't need an operator delete if we're running under -fno-exceptions.
2672  if (!getLangOpts().Exceptions) {
2673  OperatorDelete = nullptr;
2674  return false;
2675  }
2676 
2677  // Note, the name of OperatorNew might have been changed from array to
2678  // non-array by resolveAllocationOverload.
2680  OperatorNew->getDeclName().getCXXOverloadedOperator() == OO_Array_New
2681  ? OO_Array_Delete
2682  : OO_Delete);
2683 
2684  // C++ [expr.new]p19:
2685  //
2686  // If the new-expression begins with a unary :: operator, the
2687  // deallocation function's name is looked up in the global
2688  // scope. Otherwise, if the allocated type is a class type T or an
2689  // array thereof, the deallocation function's name is looked up in
2690  // the scope of T. If this lookup fails to find the name, or if
2691  // the allocated type is not a class type or array thereof, the
2692  // deallocation function's name is looked up in the global scope.
2693  LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName);
2694  if (AllocElemType->isRecordType() && DeleteScope != AFS_Global) {
2695  auto *RD =
2696  cast<CXXRecordDecl>(AllocElemType->castAs<RecordType>()->getDecl());
2697  LookupQualifiedName(FoundDelete, RD);
2698  }
2699  if (FoundDelete.isAmbiguous())
2700  return true; // FIXME: clean up expressions?
2701 
2702  // Filter out any destroying operator deletes. We can't possibly call such a
2703  // function in this context, because we're handling the case where the object
2704  // was not successfully constructed.
2705  // FIXME: This is not covered by the language rules yet.
2706  {
2707  LookupResult::Filter Filter = FoundDelete.makeFilter();
2708  while (Filter.hasNext()) {
2709  auto *FD = dyn_cast<FunctionDecl>(Filter.next()->getUnderlyingDecl());
2710  if (FD && FD->isDestroyingOperatorDelete())
2711  Filter.erase();
2712  }
2713  Filter.done();
2714  }
2715 
2716  bool FoundGlobalDelete = FoundDelete.empty();
2717  if (FoundDelete.empty()) {
2718  FoundDelete.clear(LookupOrdinaryName);
2719 
2720  if (DeleteScope == AFS_Class)
2721  return true;
2722 
2725  }
2726 
2727  FoundDelete.suppressDiagnostics();
2728 
2730 
2731  // Whether we're looking for a placement operator delete is dictated
2732  // by whether we selected a placement operator new, not by whether
2733  // we had explicit placement arguments. This matters for things like
2734  // struct A { void *operator new(size_t, int = 0); ... };
2735  // A *a = new A()
2736  //
2737  // We don't have any definition for what a "placement allocation function"
2738  // is, but we assume it's any allocation function whose
2739  // parameter-declaration-clause is anything other than (size_t).
2740  //
2741  // FIXME: Should (size_t, std::align_val_t) also be considered non-placement?
2742  // This affects whether an exception from the constructor of an overaligned
2743  // type uses the sized or non-sized form of aligned operator delete.
2744  bool isPlacementNew = !PlaceArgs.empty() || OperatorNew->param_size() != 1 ||
2745  OperatorNew->isVariadic();
2746 
2747  if (isPlacementNew) {
2748  // C++ [expr.new]p20:
2749  // A declaration of a placement deallocation function matches the
2750  // declaration of a placement allocation function if it has the
2751  // same number of parameters and, after parameter transformations
2752  // (8.3.5), all parameter types except the first are
2753  // identical. [...]
2754  //
2755  // To perform this comparison, we compute the function type that
2756  // the deallocation function should have, and use that type both
2757  // for template argument deduction and for comparison purposes.
2758  QualType ExpectedFunctionType;
2759  {
2760  auto *Proto = OperatorNew->getType()->castAs<FunctionProtoType>();
2761 
2762  SmallVector<QualType, 4> ArgTypes;
2763  ArgTypes.push_back(Context.VoidPtrTy);
2764  for (unsigned I = 1, N = Proto->getNumParams(); I < N; ++I)
2765  ArgTypes.push_back(Proto->getParamType(I));
2766 
2768  // FIXME: This is not part of the standard's rule.
2769  EPI.Variadic = Proto->isVariadic();
2770 
2771  ExpectedFunctionType
2772  = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI);
2773  }
2774 
2775  for (LookupResult::iterator D = FoundDelete.begin(),
2776  DEnd = FoundDelete.end();
2777  D != DEnd; ++D) {
2778  FunctionDecl *Fn = nullptr;
2779  if (FunctionTemplateDecl *FnTmpl =
2780  dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) {
2781  // Perform template argument deduction to try to match the
2782  // expected function type.
2783  TemplateDeductionInfo Info(StartLoc);
2784  if (DeduceTemplateArguments(FnTmpl, nullptr, ExpectedFunctionType, Fn,
2785  Info))
2786  continue;
2787  } else
2788  Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl());
2789 
2791  ExpectedFunctionType,
2792  /*AdjustExcpetionSpec*/true),
2793  ExpectedFunctionType))
2794  Matches.push_back(std::make_pair(D.getPair(), Fn));
2795  }
2796 
2797  if (getLangOpts().CUDA)
2798  EraseUnwantedCUDAMatches(dyn_cast<FunctionDecl>(CurContext), Matches);
2799  } else {
2800  // C++1y [expr.new]p22:
2801  // For a non-placement allocation function, the normal deallocation
2802  // function lookup is used
2803  //
2804  // Per [expr.delete]p10, this lookup prefers a member operator delete
2805  // without a size_t argument, but prefers a non-member operator delete
2806  // with a size_t where possible (which it always is in this case).
2808  UsualDeallocFnInfo Selected = resolveDeallocationOverload(
2809  *this, FoundDelete, /*WantSize*/ FoundGlobalDelete,
2810  /*WantAlign*/ hasNewExtendedAlignment(*this, AllocElemType),
2811  &BestDeallocFns);
2812  if (Selected)
2813  Matches.push_back(std::make_pair(Selected.Found, Selected.FD));
2814  else {
2815  // If we failed to select an operator, all remaining functions are viable
2816  // but ambiguous.
2817  for (auto Fn : BestDeallocFns)
2818  Matches.push_back(std::make_pair(Fn.Found, Fn.FD));
2819  }
2820  }
2821 
2822  // C++ [expr.new]p20:
2823  // [...] If the lookup finds a single matching deallocation
2824  // function, that function will be called; otherwise, no
2825  // deallocation function will be called.
2826  if (Matches.size() == 1) {
2827  OperatorDelete = Matches[0].second;
2828 
2829  // C++1z [expr.new]p23:
2830  // If the lookup finds a usual deallocation function (3.7.4.2)
2831  // with a parameter of type std::size_t and that function, considered
2832  // as a placement deallocation function, would have been
2833  // selected as a match for the allocation function, the program
2834  // is ill-formed.
2835  if (getLangOpts().CPlusPlus11 && isPlacementNew &&
2836  isNonPlacementDeallocationFunction(*this, OperatorDelete)) {
2837  UsualDeallocFnInfo Info(*this,
2838  DeclAccessPair::make(OperatorDelete, AS_public));
2839  // Core issue, per mail to core reflector, 2016-10-09:
2840  // If this is a member operator delete, and there is a corresponding
2841  // non-sized member operator delete, this isn't /really/ a sized
2842  // deallocation function, it just happens to have a size_t parameter.
2843  bool IsSizedDelete = Info.HasSizeT;
2844  if (IsSizedDelete && !FoundGlobalDelete) {
2845  auto NonSizedDelete =
2846  resolveDeallocationOverload(*this, FoundDelete, /*WantSize*/false,
2847  /*WantAlign*/Info.HasAlignValT);
2848  if (NonSizedDelete && !NonSizedDelete.HasSizeT &&
2849  NonSizedDelete.HasAlignValT == Info.HasAlignValT)
2850  IsSizedDelete = false;
2851  }
2852 
2853  if (IsSizedDelete) {
2854  SourceRange R = PlaceArgs.empty()
2855  ? SourceRange()
2856  : SourceRange(PlaceArgs.front()->getBeginLoc(),
2857  PlaceArgs.back()->getEndLoc());
2858  Diag(StartLoc, diag::err_placement_new_non_placement_delete) << R;
2859  if (!OperatorDelete->isImplicit())
2860  Diag(OperatorDelete->getLocation(), diag::note_previous_decl)
2861  << DeleteName;
2862  }
2863  }
2864 
2865  CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(),
2866  Matches[0].first);
2867  } else if (!Matches.empty()) {
2868  // We found multiple suitable operators. Per [expr.new]p20, that means we
2869  // call no 'operator delete' function, but we should at least warn the user.
2870  // FIXME: Suppress this warning if the construction cannot throw.
2871  Diag(StartLoc, diag::warn_ambiguous_suitable_delete_function_found)
2872  << DeleteName << AllocElemType;
2873 
2874  for (auto &Match : Matches)
2875  Diag(Match.second->getLocation(),
2876  diag::note_member_declared_here) << DeleteName;
2877  }
2878 
2879  return false;
2880 }
2881 
2882 /// DeclareGlobalNewDelete - Declare the global forms of operator new and
2883 /// delete. These are:
2884 /// @code
2885 /// // C++03:
2886 /// void* operator new(std::size_t) throw(std::bad_alloc);
2887 /// void* operator new[](std::size_t) throw(std::bad_alloc);
2888 /// void operator delete(void *) throw();
2889 /// void operator delete[](void *) throw();
2890 /// // C++11:
2891 /// void* operator new(std::size_t);
2892 /// void* operator new[](std::size_t);
2893 /// void operator delete(void *) noexcept;
2894 /// void operator delete[](void *) noexcept;
2895 /// // C++1y:
2896 /// void* operator new(std::size_t);
2897 /// void* operator new[](std::size_t);
2898 /// void operator delete(void *) noexcept;
2899 /// void operator delete[](void *) noexcept;
2900 /// void operator delete(void *, std::size_t) noexcept;
2901 /// void operator delete[](void *, std::size_t) noexcept;
2902 /// @endcode
2903 /// Note that the placement and nothrow forms of new are *not* implicitly
2904 /// declared. Their use requires including <new>.
2907  return;
2908 
2909  // The implicitly declared new and delete operators
2910  // are not supported in OpenCL.
2911  if (getLangOpts().OpenCLCPlusPlus)
2912  return;
2913 
2914  // C++ [basic.std.dynamic]p2:
2915  // [...] The following allocation and deallocation functions (18.4) are
2916  // implicitly declared in global scope in each translation unit of a
2917  // program
2918  //
2919  // C++03:
2920  // void* operator new(std::size_t) throw(std::bad_alloc);
2921  // void* operator new[](std::size_t) throw(std::bad_alloc);
2922  // void operator delete(void*) throw();
2923  // void operator delete[](void*) throw();
2924  // C++11:
2925  // void* operator new(std::size_t);
2926  // void* operator new[](std::size_t);
2927  // void operator delete(void*) noexcept;
2928  // void operator delete[](void*) noexcept;
2929  // C++1y:
2930  // void* operator new(std::size_t);
2931  // void* operator new[](std::size_t);
2932  // void operator delete(void*) noexcept;
2933  // void operator delete[](void*) noexcept;
2934  // void operator delete(void*, std::size_t) noexcept;
2935  // void operator delete[](void*, std::size_t) noexcept;
2936  //
2937  // These implicit declarations introduce only the function names operator
2938  // new, operator new[], operator delete, operator delete[].
2939  //
2940  // Here, we need to refer to std::bad_alloc, so we will implicitly declare
2941  // "std" or "bad_alloc" as necessary to form the exception specification.
2942  // However, we do not make these implicit declarations visible to name
2943  // lookup.
2944  if (!StdBadAlloc && !getLangOpts().CPlusPlus11) {
2945  // The "std::bad_alloc" class has not yet been declared, so build it
2946  // implicitly.
2950  &PP.getIdentifierTable().get("bad_alloc"),
2951  nullptr);
2952  getStdBadAlloc()->setImplicit(true);
2953  }
2954  if (!StdAlignValT && getLangOpts().AlignedAllocation) {
2955  // The "std::align_val_t" enum class has not yet been declared, so build it
2956  // implicitly.
2957  auto *AlignValT = EnumDecl::Create(
2959  &PP.getIdentifierTable().get("align_val_t"), nullptr, true, true, true);
2960  AlignValT->setIntegerType(Context.getSizeType());
2961  AlignValT->setPromotionType(Context.getSizeType());
2962  AlignValT->setImplicit(true);
2963  StdAlignValT = AlignValT;
2964  }
2965 
2966  GlobalNewDeleteDeclared = true;
2967 
2969  QualType SizeT = Context.getSizeType();
2970 
2971  auto DeclareGlobalAllocationFunctions = [&](OverloadedOperatorKind Kind,
2972  QualType Return, QualType Param) {
2974  Params.push_back(Param);
2975 
2976  // Create up to four variants of the function (sized/aligned).
2977  bool HasSizedVariant = getLangOpts().SizedDeallocation &&
2978  (Kind == OO_Delete || Kind == OO_Array_Delete);
2979  bool HasAlignedVariant = getLangOpts().AlignedAllocation;
2980 
2981  int NumSizeVariants = (HasSizedVariant ? 2 : 1);
2982  int NumAlignVariants = (HasAlignedVariant ? 2 : 1);
2983  for (int Sized = 0; Sized < NumSizeVariants; ++Sized) {
2984  if (Sized)
2985  Params.push_back(SizeT);
2986 
2987  for (int Aligned = 0; Aligned < NumAlignVariants; ++Aligned) {
2988  if (Aligned)
2989  Params.push_back(Context.getTypeDeclType(getStdAlignValT()));
2990 
2992  Context.DeclarationNames.getCXXOperatorName(Kind), Return, Params);
2993 
2994  if (Aligned)
2995  Params.pop_back();
2996  }
2997  }
2998  };
2999 
3000  DeclareGlobalAllocationFunctions(OO_New, VoidPtr, SizeT);
3001  DeclareGlobalAllocationFunctions(OO_Array_New, VoidPtr, SizeT);
3002  DeclareGlobalAllocationFunctions(OO_Delete, Context.VoidTy, VoidPtr);
3003  DeclareGlobalAllocationFunctions(OO_Array_Delete, Context.VoidTy, VoidPtr);
3004 }
3005 
3006 /// DeclareGlobalAllocationFunction - Declares a single implicit global
3007 /// allocation function if it doesn't already exist.
3009  QualType Return,
3010  ArrayRef<QualType> Params) {
3012 
3013  // Check if this function is already declared.
3014  DeclContext::lookup_result R = GlobalCtx->lookup(Name);
3015  for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end();
3016  Alloc != AllocEnd; ++Alloc) {
3017  // Only look at non-template functions, as it is the predefined,
3018  // non-templated allocation function we are trying to declare here.
3019  if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
3020  if (Func->getNumParams() == Params.size()) {
3021  llvm::SmallVector<QualType, 3> FuncParams;
3022  for (auto *P : Func->parameters())
3023  FuncParams.push_back(
3024  Context.getCanonicalType(P->getType().getUnqualifiedType()));
3025  if (llvm::makeArrayRef(FuncParams) == Params) {
3026  // Make the function visible to name lookup, even if we found it in
3027  // an unimported module. It either is an implicitly-declared global
3028  // allocation function, or is suppressing that function.
3029  Func->setVisibleDespiteOwningModule();
3030  return;
3031  }
3032  }
3033  }
3034  }
3035 
3037  /*IsVariadic=*/false, /*IsCXXMethod=*/false, /*IsBuiltin=*/true));
3038 
3039  QualType BadAllocType;
3040  bool HasBadAllocExceptionSpec
3041  = (Name.getCXXOverloadedOperator() == OO_New ||
3042  Name.getCXXOverloadedOperator() == OO_Array_New);
3043  if (HasBadAllocExceptionSpec) {
3044  if (!getLangOpts().CPlusPlus11) {
3045  BadAllocType = Context.getTypeDeclType(getStdBadAlloc());
3046  assert(StdBadAlloc && "Must have std::bad_alloc declared");
3048  EPI.ExceptionSpec.Exceptions = llvm::makeArrayRef(BadAllocType);
3049  }
3050  if (getLangOpts().NewInfallible) {
3052  }
3053  } else {
3054  EPI.ExceptionSpec =
3055  getLangOpts().CPlusPlus11 ? EST_BasicNoexcept : EST_DynamicNone;
3056  }
3057 
3058  auto CreateAllocationFunctionDecl = [&](Attr *ExtraAttr) {
3059  QualType FnType = Context.getFunctionType(Return, Params, EPI);
3061  Context, GlobalCtx, SourceLocation(), SourceLocation(), Name, FnType,
3062  /*TInfo=*/nullptr, SC_None, getCurFPFeatures().isFPConstrained(), false,
3063  true);
3064  Alloc->setImplicit();
3065  // Global allocation functions should always be visible.
3067 
3068  if (HasBadAllocExceptionSpec && getLangOpts().NewInfallible)
3069  Alloc->addAttr(
3070  ReturnsNonNullAttr::CreateImplicit(Context, Alloc->getLocation()));
3071 
3072  Alloc->addAttr(VisibilityAttr::CreateImplicit(
3073  Context, LangOpts.GlobalAllocationFunctionVisibilityHidden
3074  ? VisibilityAttr::Hidden
3075  : VisibilityAttr::Default));
3076 
3078  for (QualType T : Params) {
3079  ParamDecls.push_back(ParmVarDecl::Create(
3080  Context, Alloc, SourceLocation(), SourceLocation(), nullptr, T,
3081  /*TInfo=*/nullptr, SC_None, nullptr));
3082  ParamDecls.back()->setImplicit();
3083  }
3084  Alloc->setParams(ParamDecls);
3085  if (ExtraAttr)
3086  Alloc->addAttr(ExtraAttr);
3089  IdResolver.tryAddTopLevelDecl(Alloc, Name);
3090  };
3091 
3092  if (!LangOpts.CUDA)
3093  CreateAllocationFunctionDecl(nullptr);
3094  else {
3095  // Host and device get their own declaration so each can be
3096  // defined or re-declared independently.
3097  CreateAllocationFunctionDecl(CUDAHostAttr::CreateImplicit(Context));
3098  CreateAllocationFunctionDecl(CUDADeviceAttr::CreateImplicit(Context));
3099  }
3100 }
3101 
3103  bool CanProvideSize,
3104  bool Overaligned,
3105  DeclarationName Name) {
3107 
3108  LookupResult FoundDelete(*this, Name, StartLoc, LookupOrdinaryName);
3110 
3111  // FIXME: It's possible for this to result in ambiguity, through a
3112  // user-declared variadic operator delete or the enable_if attribute. We
3113  // should probably not consider those cases to be usual deallocation
3114  // functions. But for now we just make an arbitrary choice in that case.
3115  auto Result = resolveDeallocationOverload(*this, FoundDelete, CanProvideSize,
3116  Overaligned);
3117  assert(Result.FD && "operator delete missing from global scope?");
3118  return Result.FD;
3119 }
3120 
3122  CXXRecordDecl *RD) {
3124 
3125  FunctionDecl *OperatorDelete = nullptr;
3126  if (FindDeallocationFunction(Loc, RD, Name, OperatorDelete))
3127  return nullptr;
3128  if (OperatorDelete)
3129  return OperatorDelete;
3130 
3131  // If there's no class-specific operator delete, look up the global
3132  // non-array delete.
3134  Loc, true, hasNewExtendedAlignment(*this, Context.getRecordType(RD)),
3135  Name);
3136 }
3137 
3139  DeclarationName Name,
3140  FunctionDecl *&Operator, bool Diagnose) {
3141  LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
3142  // Try to find operator delete/operator delete[] in class scope.
3143  LookupQualifiedName(Found, RD);
3144 
3145  if (Found.isAmbiguous())
3146  return true;
3147 
3148  Found.suppressDiagnostics();
3149 
3150  bool Overaligned = hasNewExtendedAlignment(*this, Context.getRecordType(RD));
3151 
3152  // C++17 [expr.delete]p10:
3153  // If the deallocation functions have class scope, the one without a
3154  // parameter of type std::size_t is selected.
3156  resolveDeallocationOverload(*this, Found, /*WantSize*/ false,
3157  /*WantAlign*/ Overaligned, &Matches);
3158 
3159  // If we could find an overload, use it.
3160  if (Matches.size() == 1) {
3161  Operator = cast<CXXMethodDecl>(Matches[0].FD);
3162 
3163  // FIXME: DiagnoseUseOfDecl?
3164  if (Operator->isDeleted()) {
3165  if (Diagnose) {
3166  Diag(StartLoc, diag::err_deleted_function_use);
3167  NoteDeletedFunction(Operator);
3168  }
3169  return true;
3170  }
3171 
3172  if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(),
3173  Matches[0].Found, Diagnose) == AR_inaccessible)
3174  return true;
3175 
3176  return false;
3177  }
3178 
3179  // We found multiple suitable operators; complain about the ambiguity.
3180  // FIXME: The standard doesn't say to do this; it appears that the intent
3181  // is that this should never happen.
3182  if (!Matches.empty()) {
3183  if (Diagnose) {
3184  Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found)
3185  << Name << RD;
3186  for (auto &Match : Matches)
3187  Diag(Match.FD->getLocation(), diag::note_member_declared_here) << Name;
3188  }
3189  return true;
3190  }
3191 
3192  // We did find operator delete/operator delete[] declarations, but
3193  // none of them were suitable.
3194  if (!Found.empty()) {
3195  if (Diagnose) {
3196  Diag(StartLoc, diag::err_no_suitable_delete_member_function_found)
3197  << Name << RD;
3198 
3199  for (NamedDecl *D : Found)
3200  Diag(D->getUnderlyingDecl()->getLocation(),
3201  diag::note_member_declared_here) << Name;
3202  }
3203  return true;
3204  }
3205 
3206  Operator = nullptr;
3207  return false;
3208 }
3209 
3210 namespace {
3211 /// Checks whether delete-expression, and new-expression used for
3212 /// initializing deletee have the same array form.
3213 class MismatchingNewDeleteDetector {
3214 public:
3215  enum MismatchResult {
3216  /// Indicates that there is no mismatch or a mismatch cannot be proven.
3217  NoMismatch,
3218  /// Indicates that variable is initialized with mismatching form of \a new.
3219  VarInitMismatches,
3220  /// Indicates that member is initialized with mismatching form of \a new.
3221  MemberInitMismatches,
3222  /// Indicates that 1 or more constructors' definitions could not been
3223  /// analyzed, and they will be checked again at the end of translation unit.
3224  AnalyzeLater
3225  };
3226 
3227  /// \param EndOfTU True, if this is the final analysis at the end of
3228  /// translation unit. False, if this is the initial analysis at the point
3229  /// delete-expression was encountered.
3230  explicit MismatchingNewDeleteDetector(bool EndOfTU)
3231  : Field(nullptr), IsArrayForm(false), EndOfTU(EndOfTU),
3232  HasUndefinedConstructors(false) {}
3233 
3234  /// Checks whether pointee of a delete-expression is initialized with
3235  /// matching form of new-expression.
3236  ///
3237  /// If return value is \c VarInitMismatches or \c MemberInitMismatches at the
3238  /// point where delete-expression is encountered, then a warning will be
3239  /// issued immediately. If return value is \c AnalyzeLater at the point where
3240  /// delete-expression is seen, then member will be analyzed at the end of
3241  /// translation unit. \c AnalyzeLater is returned iff at least one constructor
3242  /// couldn't be analyzed. If at least one constructor initializes the member
3243  /// with matching type of new, the return value is \c NoMismatch.
3244  MismatchResult analyzeDeleteExpr(const CXXDeleteExpr *DE);
3245  /// Analyzes a class member.
3246  /// \param Field Class member to analyze.
3247  /// \param DeleteWasArrayForm Array form-ness of the delete-expression used
3248  /// for deleting the \p Field.
3249  MismatchResult analyzeField(FieldDecl *Field, bool DeleteWasArrayForm);
3250  FieldDecl *Field;
3251  /// List of mismatching new-expressions used for initialization of the pointee
3253  /// Indicates whether delete-expression was in array form.
3254  bool IsArrayForm;
3255 
3256 private:
3257  const bool EndOfTU;
3258  /// Indicates that there is at least one constructor without body.
3259  bool HasUndefinedConstructors;
3260  /// Returns \c CXXNewExpr from given initialization expression.
3261  /// \param E Expression used for initializing pointee in delete-expression.
3262  /// E can be a single-element \c InitListExpr consisting of new-expression.
3263  const CXXNewExpr *getNewExprFromInitListOrExpr(const Expr *E);
3264  /// Returns whether member is initialized with mismatching form of
3265  /// \c new either by the member initializer or in-class initialization.
3266  ///
3267  /// If bodies of all constructors are not visible at the end of translation
3268  /// unit or at least one constructor initializes member with the matching
3269  /// form of \c new, mismatch cannot be proven, and this function will return
3270  /// \c NoMismatch.
3271  MismatchResult analyzeMemberExpr(const MemberExpr *ME);
3272  /// Returns whether variable is initialized with mismatching form of
3273  /// \c new.
3274  ///
3275  /// If variable is initialized with matching form of \c new or variable is not
3276  /// initialized with a \c new expression, this function will return true.
3277  /// If variable is initialized with mismatching form of \c new, returns false.
3278  /// \param D Variable to analyze.
3279  bool hasMatchingVarInit(const DeclRefExpr *D);
3280  /// Checks whether the constructor initializes pointee with mismatching
3281  /// form of \c new.
3282  ///
3283  /// Returns true, if member is initialized with matching form of \c new in
3284  /// member initializer list. Returns false, if member is initialized with the
3285  /// matching form of \c new in this constructor's initializer or given
3286  /// constructor isn't defined at the point where delete-expression is seen, or
3287  /// member isn't initialized by the constructor.
3288  bool hasMatchingNewInCtor(const CXXConstructorDecl *CD);
3289  /// Checks whether member is initialized with matching form of
3290  /// \c new in member initializer list.
3291  bool hasMatchingNewInCtorInit(const CXXCtorInitializer *CI);
3292  /// Checks whether member is initialized with mismatching form of \c new by
3293  /// in-class initializer.
3294  MismatchResult analyzeInClassInitializer();
3295 };
3296 }
3297 
3298 MismatchingNewDeleteDetector::MismatchResult
3299 MismatchingNewDeleteDetector::analyzeDeleteExpr(const CXXDeleteExpr *DE) {
3300  NewExprs.clear();
3301  assert(DE && "Expected delete-expression");
3302  IsArrayForm = DE->isArrayForm();
3303  const Expr *E = DE->getArgument()->IgnoreParenImpCasts();
3304  if (const MemberExpr *ME = dyn_cast<const MemberExpr>(E)) {
3305  return analyzeMemberExpr(ME);
3306  } else if (const DeclRefExpr *D = dyn_cast<const DeclRefExpr>(E)) {
3307  if (!hasMatchingVarInit(D))
3308  return VarInitMismatches;
3309  }
3310  return NoMismatch;
3311 }
3312 
3313 const CXXNewExpr *
3314 MismatchingNewDeleteDetector::getNewExprFromInitListOrExpr(const Expr *E) {
3315  assert(E != nullptr && "Expected a valid initializer expression");
3316  E = E->IgnoreParenImpCasts();
3317  if (const InitListExpr *ILE = dyn_cast<const InitListExpr>(E)) {
3318  if (ILE->getNumInits() == 1)
3319  E = dyn_cast<const CXXNewExpr>(ILE->getInit(0)->IgnoreParenImpCasts());
3320  }
3321 
3322  return dyn_cast_or_null<const CXXNewExpr>(E);
3323 }
3324 
3325 bool MismatchingNewDeleteDetector::hasMatchingNewInCtorInit(
3326  const CXXCtorInitializer *CI) {
3327  const CXXNewExpr *NE = nullptr;
3328  if (Field == CI->getMember() &&
3329  (NE = getNewExprFromInitListOrExpr(CI->getInit()))) {
3330  if (NE->isArray() == IsArrayForm)
3331  return true;
3332  else
3333  NewExprs.push_back(NE);
3334  }
3335  return false;
3336 }
3337 
3338 bool MismatchingNewDeleteDetector::hasMatchingNewInCtor(
3339  const CXXConstructorDecl *CD) {
3340  if (CD->isImplicit())
3341  return false;
3342  const FunctionDecl *Definition = CD;
3343  if (!CD->isThisDeclarationADefinition() && !CD->isDefined(Definition)) {
3344  HasUndefinedConstructors = true;
3345  return EndOfTU;
3346  }
3347  for (const auto *CI : cast<const CXXConstructorDecl>(Definition)->inits()) {
3348  if (hasMatchingNewInCtorInit(CI))
3349  return true;
3350  }
3351  return false;
3352 }
3353 
3354 MismatchingNewDeleteDetector::MismatchResult
3355 MismatchingNewDeleteDetector::analyzeInClassInitializer() {
3356  assert(Field != nullptr && "This should be called only for members");
3357  const Expr *InitExpr = Field->getInClassInitializer();
3358  if (!InitExpr)
3359  return EndOfTU ? NoMismatch : AnalyzeLater;
3360  if (const CXXNewExpr *NE = getNewExprFromInitListOrExpr(InitExpr)) {
3361  if (NE->isArray() != IsArrayForm) {
3362  NewExprs.push_back(NE);
3363  return MemberInitMismatches;
3364  }
3365  }
3366  return NoMismatch;
3367 }
3368 
3369 MismatchingNewDeleteDetector::MismatchResult
3370 MismatchingNewDeleteDetector::analyzeField(FieldDecl *Field,
3371  bool DeleteWasArrayForm) {
3372  assert(Field != nullptr && "Analysis requires a valid class member.");
3373  this->Field = Field;
3374  IsArrayForm = DeleteWasArrayForm;
3375  const CXXRecordDecl *RD = cast<const CXXRecordDecl>(Field->getParent());
3376  for (const auto *CD : RD->ctors()) {
3377  if (hasMatchingNewInCtor(CD))
3378  return NoMismatch;
3379  }
3380  if (HasUndefinedConstructors)
3381  return EndOfTU ? NoMismatch : AnalyzeLater;
3382  if (!NewExprs.empty())
3383  return MemberInitMismatches;
3384  return Field->hasInClassInitializer() ? analyzeInClassInitializer()
3385  : NoMismatch;
3386 }
3387 
3388 MismatchingNewDeleteDetector::MismatchResult
3389 MismatchingNewDeleteDetector::analyzeMemberExpr(const MemberExpr *ME) {
3390  assert(ME != nullptr && "Expected a member expression");
3391  if (FieldDecl *F = dyn_cast<FieldDecl>(ME->getMemberDecl()))
3392  return analyzeField(F, IsArrayForm);
3393  return NoMismatch;
3394 }
3395 
3396 bool MismatchingNewDeleteDetector::hasMatchingVarInit(const DeclRefExpr *D) {
3397  const CXXNewExpr *NE = nullptr;
3398  if (const VarDecl *VD = dyn_cast<const VarDecl>(D->getDecl())) {
3399  if (VD->hasInit() && (NE = getNewExprFromInitListOrExpr(VD->getInit())) &&
3400  NE->isArray() != IsArrayForm) {
3401  NewExprs.push_back(NE);
3402  }
3403  }
3404  return NewExprs.empty();
3405 }
3406 
3407 static void
3409  const MismatchingNewDeleteDetector &Detector) {
3410  SourceLocation EndOfDelete = SemaRef.getLocForEndOfToken(DeleteLoc);
3411  FixItHint H;
3412  if (!Detector.IsArrayForm)
3413  H = FixItHint::CreateInsertion(EndOfDelete, "[]");
3414  else {
3416  DeleteLoc, tok::l_square, SemaRef.getSourceManager(),
3417  SemaRef.getLangOpts(), true);
3418  if (RSquare.isValid())
3419  H = FixItHint::CreateRemoval(SourceRange(EndOfDelete, RSquare));
3420  }
3421  SemaRef.Diag(DeleteLoc, diag::warn_mismatched_delete_new)
3422  << Detector.IsArrayForm << H;
3423 
3424  for (const auto *NE : Detector.NewExprs)
3425  SemaRef.Diag(NE->getExprLoc(), diag::note_allocated_here)
3426  << Detector.IsArrayForm;
3427 }
3428 
3429 void Sema::AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE) {
3430  if (Diags.isIgnored(diag::warn_mismatched_delete_new, SourceLocation()))
3431  return;
3432  MismatchingNewDeleteDetector Detector(/*EndOfTU=*/false);
3433  switch (Detector.analyzeDeleteExpr(DE)) {
3434  case MismatchingNewDeleteDetector::VarInitMismatches:
3435  case MismatchingNewDeleteDetector::MemberInitMismatches: {
3436  DiagnoseMismatchedNewDelete(*this, DE->getBeginLoc(), Detector);
3437  break;
3438  }
3439  case MismatchingNewDeleteDetector::AnalyzeLater: {
3440  DeleteExprs[Detector.Field].push_back(
3441  std::make_pair(DE->getBeginLoc(), DE->isArrayForm()));
3442  break;
3443  }
3444  case MismatchingNewDeleteDetector::NoMismatch:
3445  break;
3446  }
3447 }
3448 
3449 void Sema::AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
3450  bool DeleteWasArrayForm) {
3451  MismatchingNewDeleteDetector Detector(/*EndOfTU=*/true);
3452  switch (Detector.analyzeField(Field, DeleteWasArrayForm)) {
3453  case MismatchingNewDeleteDetector::VarInitMismatches:
3454  llvm_unreachable("This analysis should have been done for class members.");
3455  case MismatchingNewDeleteDetector::AnalyzeLater:
3456  llvm_unreachable("Analysis cannot be postponed any point beyond end of "
3457  "translation unit.");
3458  case MismatchingNewDeleteDetector::MemberInitMismatches:
3459  DiagnoseMismatchedNewDelete(*this, DeleteLoc, Detector);
3460  break;
3461  case MismatchingNewDeleteDetector::NoMismatch:
3462  break;
3463  }
3464 }
3465 
3466 /// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in:
3467 /// @code ::delete ptr; @endcode
3468 /// or
3469 /// @code delete [] ptr; @endcode
3470 ExprResult
3471 Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
3472  bool ArrayForm, Expr *ExE) {
3473  // C++ [expr.delete]p1:
3474  // The operand shall have a pointer type, or a class type having a single
3475  // non-explicit conversion function to a pointer type. The result has type
3476  // void.
3477  //
3478  // DR599 amends "pointer type" to "pointer to object type" in both cases.
3479 
3480  ExprResult Ex = ExE;
3481  FunctionDecl *OperatorDelete = nullptr;
3482  bool ArrayFormAsWritten = ArrayForm;
3483  bool UsualArrayDeleteWantsSize = false;
3484 
3485  if (!Ex.get()->isTypeDependent()) {
3486  // Perform lvalue-to-rvalue cast, if needed.
3487  Ex = DefaultLvalueConversion(Ex.get());
3488  if (Ex.isInvalid())
3489  return ExprError();
3490 
3491  QualType Type = Ex.get()->getType();
3492 
3493  class DeleteConverter : public ContextualImplicitConverter {
3494  public:
3495  DeleteConverter() : ContextualImplicitConverter(false, true) {}
3496 
3497  bool match(QualType ConvType) override {
3498  // FIXME: If we have an operator T* and an operator void*, we must pick
3499  // the operator T*.
3500  if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
3501  if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType())
3502  return true;
3503  return false;
3504  }
3505 
3506  SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
3507  QualType T) override {
3508  return S.Diag(Loc, diag::err_delete_operand) << T;
3509  }
3510 
3511  SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
3512  QualType T) override {
3513  return S.Diag(Loc, diag::err_delete_incomplete_class_type) << T;
3514  }
3515 
3516  SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
3517  QualType T,
3518  QualType ConvTy) override {
3519  return S.Diag(Loc, diag::err_delete_explicit_conversion) << T << ConvTy;
3520  }
3521 
3522  SemaDiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
3523  QualType ConvTy) override {
3524  return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3525  << ConvTy;
3526  }
3527 
3528  SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
3529  QualType T) override {
3530  return S.Diag(Loc, diag::err_ambiguous_delete_operand) << T;
3531  }
3532 
3533  SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
3534  QualType ConvTy) override {
3535  return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3536  << ConvTy;
3537  }
3538 
3539  SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
3540  QualType T,
3541  QualType ConvTy) override {
3542  llvm_unreachable("conversion functions are permitted");
3543  }
3544  } Converter;
3545 
3546  Ex = PerformContextualImplicitConversion(StartLoc, Ex.get(), Converter);
3547  if (Ex.isInvalid())
3548  return ExprError();
3549  Type = Ex.get()->getType();
3550  if (!Converter.match(Type))
3551  // FIXME: PerformContextualImplicitConversion should return ExprError
3552  // itself in this case.
3553  return ExprError();
3554 
3555  QualType Pointee = Type->castAs<PointerType>()->getPointeeType();
3556  QualType PointeeElem = Context.getBaseElementType(Pointee);
3557 
3558  if (Pointee.getAddressSpace() != LangAS::Default &&
3559  !getLangOpts().OpenCLCPlusPlus)
3560  return Diag(Ex.get()->getBeginLoc(),
3561  diag::err_address_space_qualified_delete)
3562  << Pointee.getUnqualifiedType()
3564 
3565  CXXRecordDecl *PointeeRD = nullptr;
3566  if (Pointee->isVoidType() && !isSFINAEContext()) {
3567  // The C++ standard bans deleting a pointer to a non-object type, which
3568  // effectively bans deletion of "void*". However, most compilers support
3569  // this, so we treat it as a warning unless we're in a SFINAE context.
3570  Diag(StartLoc, diag::ext_delete_void_ptr_operand)
3571  << Type << Ex.get()->getSourceRange();
3572  } else if (Pointee->isFunctionType() || Pointee->isVoidType() ||
3573  Pointee->isSizelessType()) {
3574  return ExprError(Diag(StartLoc, diag::err_delete_operand)
3575  << Type << Ex.get()->getSourceRange());
3576  } else if (!Pointee->isDependentType()) {
3577  // FIXME: This can result in errors if the definition was imported from a
3578  // module but is hidden.
3579  if (!RequireCompleteType(StartLoc, Pointee,
3580  diag::warn_delete_incomplete, Ex.get())) {
3581  if (const RecordType *RT = PointeeElem->getAs<RecordType>())
3582  PointeeRD = cast<CXXRecordDecl>(RT->getDecl());
3583  }
3584  }
3585 
3586  if (Pointee->isArrayType() && !ArrayForm) {
3587  Diag(StartLoc, diag::warn_delete_array_type)
3588  << Type << Ex.get()->getSourceRange()
3589  << FixItHint::CreateInsertion(getLocForEndOfToken(StartLoc), "[]");
3590  ArrayForm = true;
3591  }
3592 
3594  ArrayForm ? OO_Array_Delete : OO_Delete);
3595 
3596  if (PointeeRD) {
3597  if (!UseGlobal &&
3598  FindDeallocationFunction(StartLoc, PointeeRD, DeleteName,
3599  OperatorDelete))
3600  return ExprError();
3601 
3602  // If we're allocating an array of records, check whether the
3603  // usual operator delete[] has a size_t parameter.
3604  if (ArrayForm) {
3605  // If the user specifically asked to use the global allocator,
3606  // we'll need to do the lookup into the class.
3607  if (UseGlobal)
3608  UsualArrayDeleteWantsSize =
3609  doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem);
3610 
3611  // Otherwise, the usual operator delete[] should be the
3612  // function we just found.
3613  else if (OperatorDelete && isa<CXXMethodDecl>(OperatorDelete))
3614  UsualArrayDeleteWantsSize =
3615  UsualDeallocFnInfo(*this,
3616  DeclAccessPair::make(OperatorDelete, AS_public))
3617  .HasSizeT;
3618  }
3619 
3620  if (!PointeeRD->hasIrrelevantDestructor())
3621  if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3622  MarkFunctionReferenced(StartLoc,
3623  const_cast<CXXDestructorDecl*>(Dtor));
3624  if (DiagnoseUseOfDecl(Dtor, StartLoc))
3625  return ExprError();
3626  }
3627 
3628  CheckVirtualDtorCall(PointeeRD->getDestructor(), StartLoc,
3629  /*IsDelete=*/true, /*CallCanBeVirtual=*/true,
3630  /*WarnOnNonAbstractTypes=*/!ArrayForm,
3631  SourceLocation());
3632  }
3633 
3634  if (!OperatorDelete) {
3635  if (getLangOpts().OpenCLCPlusPlus) {
3636  Diag(StartLoc, diag::err_openclcxx_not_supported) << "default delete";
3637  return ExprError();
3638  }
3639 
3640  bool IsComplete = isCompleteType(StartLoc, Pointee);
3641  bool CanProvideSize =
3642  IsComplete && (!ArrayForm || UsualArrayDeleteWantsSize ||
3643  Pointee.isDestructedType());
3644  bool Overaligned = hasNewExtendedAlignment(*this, Pointee);
3645 
3646  // Look for a global declaration.
3647  OperatorDelete = FindUsualDeallocationFunction(StartLoc, CanProvideSize,
3648  Overaligned, DeleteName);
3649  }
3650 
3651  MarkFunctionReferenced(StartLoc, OperatorDelete);
3652 
3653  // Check access and ambiguity of destructor if we're going to call it.
3654  // Note that this is required even for a virtual delete.
3655  bool IsVirtualDelete = false;
3656  if (PointeeRD) {
3657  if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3658  CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor,
3659  PDiag(diag::err_access_dtor) << PointeeElem);
3660  IsVirtualDelete = Dtor->isVirtual();
3661  }
3662  }
3663 
3664  DiagnoseUseOfDecl(OperatorDelete, StartLoc);
3665 
3666  // Convert the operand to the type of the first parameter of operator
3667  // delete. This is only necessary if we selected a destroying operator
3668  // delete that we are going to call (non-virtually); converting to void*
3669  // is trivial and left to AST consumers to handle.
3670  QualType ParamType = OperatorDelete->getParamDecl(0)->getType();
3671  if (!IsVirtualDelete && !ParamType->getPointeeType()->isVoidType()) {
3672  Qualifiers Qs = Pointee.getQualifiers();
3673  if (Qs.hasCVRQualifiers()) {
3674  // Qualifiers are irrelevant to this conversion; we're only looking
3675  // for access and ambiguity.
3676  Qs.removeCVRQualifiers();
3677  QualType Unqual = Context.getPointerType(
3679  Ex = ImpCastExprToType(Ex.get(), Unqual, CK_NoOp);
3680  }
3681  Ex = PerformImplicitConversion(Ex.get(), ParamType, AA_Passing);
3682  if (Ex.isInvalid())
3683  return ExprError();
3684  }
3685  }
3686 
3687  CXXDeleteExpr *Result = new (Context) CXXDeleteExpr(
3688  Context.VoidTy, UseGlobal, ArrayForm, ArrayFormAsWritten,
3689  UsualArrayDeleteWantsSize, OperatorDelete, Ex.get(), StartLoc);
3690  AnalyzeDeleteExprMismatch(Result);
3691  return Result;
3692 }
3693 
3695  bool IsDelete,
3696  FunctionDecl *&Operator) {
3697 
3699  IsDelete ? OO_Delete : OO_New);
3700 
3701  LookupResult R(S, NewName, TheCall->getBeginLoc(), Sema::LookupOrdinaryName);
3703  assert(!R.empty() && "implicitly declared allocation functions not found");
3704  assert(!R.isAmbiguous() && "global allocation functions are ambiguous");
3705 
3706  // We do our own custom access checks below.
3707  R.suppressDiagnostics();
3708 
3709  SmallVector<Expr *, 8> Args(TheCall->arg_begin(), TheCall->arg_end());
3710  OverloadCandidateSet Candidates(R.getNameLoc(),
3712  for (LookupResult::iterator FnOvl = R.begin(), FnOvlEnd = R.end();
3713  FnOvl != FnOvlEnd; ++FnOvl) {
3714  // Even member operator new/delete are implicitly treated as
3715  // static, so don't use AddMemberCandidate.
3716  NamedDecl *D = (*FnOvl)->getUnderlyingDecl();
3717 
3718  if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
3719  S.AddTemplateOverloadCandidate(FnTemplate, FnOvl.getPair(),
3720  /*ExplicitTemplateArgs=*/nullptr, Args,
3721  Candidates,
3722  /*SuppressUserConversions=*/false);
3723  continue;
3724  }
3725 
3726  FunctionDecl *Fn = cast<FunctionDecl>(D);
3727  S.AddOverloadCandidate(Fn, FnOvl.getPair(), Args, Candidates,
3728  /*SuppressUserConversions=*/false);
3729  }
3730 
3731  SourceRange Range = TheCall->getSourceRange();
3732 
3733  // Do the resolution.
3735  switch (Candidates.BestViableFunction(S, R.getNameLoc(), Best)) {
3736  case OR_Success: {
3737  // Got one!
3738  FunctionDecl *FnDecl = Best->Function;
3739  assert(R.getNamingClass() == nullptr &&
3740  "class members should not be considered");
3741 
3742  if (!FnDecl->isReplaceableGlobalAllocationFunction()) {
3743  S.Diag(R.getNameLoc(), diag::err_builtin_operator_new_delete_not_usual)
3744  << (IsDelete ? 1 : 0) << Range;
3745  S.Diag(FnDecl->getLocation(), diag::note_non_usual_function_declared_here)
3746  << R.getLookupName() << FnDecl->getSourceRange();
3747  return true;
3748  }
3749 
3750  Operator = FnDecl;
3751  return false;
3752  }
3753 
3754  case OR_No_Viable_Function:
3755  Candidates.NoteCandidates(
3757  S.PDiag(diag::err_ovl_no_viable_function_in_call)
3758  << R.getLookupName() << Range),
3759  S, OCD_AllCandidates, Args);
3760  return true;
3761 
3762  case OR_Ambiguous:
3763  Candidates.NoteCandidates(
3765  S.PDiag(diag::err_ovl_ambiguous_call)
3766  << R.getLookupName() << Range),
3767  S, OCD_AmbiguousCandidates, Args);
3768  return true;
3769 
3770  case OR_Deleted: {
3771  Candidates.NoteCandidates(
3772  PartialDiagnosticAt(R.getNameLoc(), S.PDiag(diag::err_ovl_deleted_call)
3773  << R.getLookupName() << Range),
3774  S, OCD_AllCandidates, Args);
3775  return true;
3776  }
3777  }
3778  llvm_unreachable("Unreachable, bad result from BestViableFunction");
3779 }
3780 
3781 ExprResult
3782 Sema::SemaBuiltinOperatorNewDeleteOverloaded(ExprResult TheCallResult,
3783  bool IsDelete) {
3784  CallExpr *TheCall = cast<CallExpr>(TheCallResult.get());
3785  if (!getLangOpts().CPlusPlus) {
3786  Diag(TheCall->getExprLoc(), diag::err_builtin_requires_language)
3787  << (IsDelete ? "__builtin_operator_delete" : "__builtin_operator_new")
3788  << "C++";
3789  return ExprError();
3790  }
3791  // CodeGen assumes it can find the global new and delete to call,
3792  // so ensure that they are declared.
3794 
3795  FunctionDecl *OperatorNewOrDelete = nullptr;
3796  if (resolveBuiltinNewDeleteOverload(*this, TheCall, IsDelete,
3797  OperatorNewOrDelete))
3798  return ExprError();
3799  assert(OperatorNewOrDelete && "should be found");
3800 
3801  DiagnoseUseOfDecl(OperatorNewOrDelete, TheCall->getExprLoc());
3802  MarkFunctionReferenced(TheCall->getExprLoc(), OperatorNewOrDelete);
3803 
3804  TheCall->setType(OperatorNewOrDelete->getReturnType());
3805  for (unsigned i = 0; i != TheCall->getNumArgs(); ++i) {
3806  QualType ParamTy = OperatorNewOrDelete->getParamDecl(i)->getType();
3807  InitializedEntity Entity =
3810  Entity, TheCall->getArg(i)->getBeginLoc(), TheCall->getArg(i));
3811  if (Arg.isInvalid())
3812  return ExprError();
3813  TheCall->setArg(i, Arg.get());
3814  }
3815  auto Callee = dyn_cast<ImplicitCastExpr>(TheCall->getCallee());
3816  assert(Callee && Callee->getCastKind() == CK_BuiltinFnToFnPtr &&
3817  "Callee expected to be implicit cast to a builtin function pointer");
3818  Callee->setType(OperatorNewOrDelete->getType());
3819 
3820  return TheCallResult;
3821 }
3822 
3824  bool IsDelete, bool CallCanBeVirtual,
3825  bool WarnOnNonAbstractTypes,
3826  SourceLocation DtorLoc) {
3827  if (!dtor || dtor->isVirtual() || !CallCanBeVirtual || isUnevaluatedContext())
3828  return;
3829 
3830  // C++ [expr.delete]p3:
3831  // In the first alternative (delete object), if the static type of the
3832  // object to be deleted is different from its dynamic type, the static
3833  // type shall be a base class of the dynamic type of the object to be
3834  // deleted and the static type shall have a virtual destructor or the
3835  // behavior is undefined.
3836  //
3837  const CXXRecordDecl *PointeeRD = dtor->getParent();
3838  // Note: a final class cannot be derived from, no issue there
3839  if (!PointeeRD->isPolymorphic() || PointeeRD->hasAttr<FinalAttr>())
3840  return;
3841 
3842  // If the superclass is in a system header, there's nothing that can be done.
3843  // The `delete` (where we emit the warning) can be in a system header,
3844  // what matters for this warning is where the deleted type is defined.
3845  if (getSourceManager().isInSystemHeader(PointeeRD->getLocation()))
3846  return;
3847 
3848  QualType ClassType = dtor->getThisType()->getPointeeType();
3849  if (PointeeRD->isAbstract()) {
3850  // If the class is abstract, we warn by default, because we're
3851  // sure the code has undefined behavior.
3852  Diag(Loc, diag::warn_delete_abstract_non_virtual_dtor) << (IsDelete ? 0 : 1)
3853  << ClassType;
3854  } else if (WarnOnNonAbstractTypes) {
3855  // Otherwise, if this is not an array delete, it's a bit suspect,
3856  // but not necessarily wrong.
3857  Diag(Loc, diag::warn_delete_non_virtual_dtor) << (IsDelete ? 0 : 1)
3858  << ClassType;
3859  }
3860  if (!IsDelete) {
3861  std::string TypeStr;
3862  ClassType.getAsStringInternal(TypeStr, getPrintingPolicy());
3863  Diag(DtorLoc, diag::note_delete_non_virtual)
3864  << FixItHint::CreateInsertion(DtorLoc, TypeStr + "::");
3865  }
3866 }
3867 
3869  SourceLocation StmtLoc,
3870  ConditionKind CK) {
3871  ExprResult E =
3872  CheckConditionVariable(cast<VarDecl>(ConditionVar), StmtLoc, CK);
3873  if (E.isInvalid())
3874  return ConditionError();
3875  return ConditionResult(*this, ConditionVar, MakeFullExpr(E.get(), StmtLoc),
3877 }
3878 
3879 /// Check the use of the given variable as a C++ condition in an if,
3880 /// while, do-while, or switch statement.
3882  SourceLocation StmtLoc,
3883  ConditionKind CK) {
3884  if (ConditionVar->isInvalidDecl())
3885  return ExprError();
3886 
3887  QualType T = ConditionVar->getType();
3888 
3889  // C++ [stmt.select]p2:
3890  // The declarator shall not specify a function or an array.
3891  if (T->isFunctionType())
3892  return ExprError(Diag(ConditionVar->getLocation(),
3893  diag::err_invalid_use_of_function_type)
3894  << ConditionVar->getSourceRange());
3895  else if (T->isArrayType())
3896  return ExprError(Diag(ConditionVar->getLocation(),
3897  diag::err_invalid_use_of_array_type)
3898  << ConditionVar->getSourceRange());
3899 
3901  ConditionVar, ConditionVar->getType().getNonReferenceType(), VK_LValue,
3902  ConditionVar->getLocation());
3903 
3904  switch (CK) {
3906  return CheckBooleanCondition(StmtLoc, Condition.get());
3907 
3909  return CheckBooleanCondition(StmtLoc, Condition.get(), true);
3910 
3911  case ConditionKind::Switch:
3912  return CheckSwitchCondition(StmtLoc, Condition.get());
3913  }
3914 
3915  llvm_unreachable("unexpected condition kind");
3916 }
3917 
3918 /// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
3919 ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr, bool IsConstexpr) {
3920  // C++11 6.4p4:
3921  // The value of a condition that is an initialized declaration in a statement
3922  // other than a switch statement is the value of the declared variable
3923  // implicitly converted to type bool. If that conversion is ill-formed, the
3924  // program is ill-formed.
3925  // The value of a condition that is an expression is the value of the
3926  // expression, implicitly converted to bool.
3927  //
3928  // C++2b 8.5.2p2
3929  // If the if statement is of the form if constexpr, the value of the condition
3930  // is contextually converted to bool and the converted expression shall be
3931  // a constant expression.
3932  //
3933 
3935  if (!IsConstexpr || E.isInvalid() || E.get()->isValueDependent())
3936  return E;
3937 
3938  // FIXME: Return this value to the caller so they don't need to recompute it.
3939  llvm::APSInt Cond;
3941  E.get(), &Cond,
3942  diag::err_constexpr_if_condition_expression_is_not_constant);
3943  return E;
3944 }
3945 
3946 /// Helper function to determine whether this is the (deprecated) C++
3947 /// conversion from a string literal to a pointer to non-const char or
3948 /// non-const wchar_t (for narrow and wide string literals,
3949 /// respectively).
3950 bool
3952  // Look inside the implicit cast, if it exists.
3953  if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From))
3954  From = Cast->getSubExpr();
3955 
3956  // A string literal (2.13.4) that is not a wide string literal can
3957  // be converted to an rvalue of type "pointer to char"; a wide
3958  // string literal can be converted to an rvalue of type "pointer
3959  // to wchar_t" (C++ 4.2p2).
3960  if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens()))
3961  if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
3962  if (const BuiltinType *ToPointeeType
3963  = ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
3964  // This conversion is considered only when there is an
3965  // explicit appropriate pointer target type (C++ 4.2p2).
3966  if (!ToPtrType->getPointeeType().hasQualifiers()) {
3967  switch (StrLit->getKind()) {
3968  case StringLiteral::UTF8:
3969  case StringLiteral::UTF16:
3970  case StringLiteral::UTF32:
3971  // We don't allow UTF literals to be implicitly converted
3972  break;
3973  case StringLiteral::Ascii:
3974  return (ToPointeeType->getKind() == BuiltinType::Char_U ||
3975  ToPointeeType->getKind() == BuiltinType::Char_S);
3976  case StringLiteral::Wide:
3978  QualType(ToPointeeType, 0));
3979  }
3980  }
3981  }
3982 
3983  return false;
3984 }
3985 
3987  SourceLocation CastLoc,
3988  QualType Ty,
3989  CastKind Kind,
3990  CXXMethodDecl *Method,
3991  DeclAccessPair FoundDecl,
3992  bool HadMultipleCandidates,
3993  Expr *From) {
3994  switch (Kind) {
3995  default: llvm_unreachable("Unhandled cast kind!");
3996  case CK_ConstructorConversion: {
3997  CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method);
3998  SmallVector<Expr*, 8> ConstructorArgs;
3999 
4000  if (S.RequireNonAbstractType(CastLoc, Ty,
4001  diag::err_allocation_of_abstract_type))
4002  return ExprError();
4003 
4004  if (S.CompleteConstructorCall(Constructor, Ty, From, CastLoc,
4005  ConstructorArgs))
4006  return ExprError();
4007 
4008  S.CheckConstructorAccess(CastLoc, Constructor, FoundDecl,
4010  if (S.DiagnoseUseOfDecl(Method, CastLoc))
4011  return ExprError();
4012 
4013  ExprResult Result = S.BuildCXXConstructExpr(
4014  CastLoc, Ty, FoundDecl, cast<CXXConstructorDecl>(Method),
4015  ConstructorArgs, HadMultipleCandidates,
4016  /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
4018  if (Result.isInvalid())
4019  return ExprError();
4020 
4021  return S.MaybeBindToTemporary(Result.getAs<Expr>());
4022  }
4023 
4024  case CK_UserDefinedConversion: {
4025  assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
4026 
4027  S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ nullptr, FoundDecl);
4028  if (S.DiagnoseUseOfDecl(Method, CastLoc))
4029  return ExprError();
4030 
4031  // Create an implicit call expr that calls it.
4032  CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method);
4033  ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv,
4034  HadMultipleCandidates);
4035  if (Result.isInvalid())
4036  return ExprError();
4037  // Record usage of conversion in an implicit cast.
4038  Result = ImplicitCastExpr::Create(S.Context, Result.get()->getType(),
4039  CK_UserDefinedConversion, Result.get(),
4040  nullptr, Result.get()->getValueKind(),
4041  S.CurFPFeatureOverrides());
4042 
4043  return S.MaybeBindToTemporary(Result.get());
4044  }
4045  }
4046 }
4047 
4048 /// PerformImplicitConversion - Perform an implicit conversion of the
4049 /// expression From to the type ToType using the pre-computed implicit
4050 /// conversion sequence ICS. Returns the converted
4051 /// expression. Action is the kind of conversion we're performing,
4052 /// used in the error message.
4053 ExprResult
4055  const ImplicitConversionSequence &ICS,
4056  AssignmentAction Action,
4057  CheckedConversionKind CCK) {
4058  // C++ [over.match.oper]p7: [...] operands of class type are converted [...]
4059  if (CCK == CCK_ForBuiltinOverloadedOp && !From->getType()->isRecordType())
4060  return From;
4061 
4062  switch (ICS.getKind()) {
4064  ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard,
4065  Action, CCK);
4066  if (Res.isInvalid())
4067  return ExprError();
4068  From = Res.get();
4069  break;
4070  }
4071 
4073 
4076  QualType BeforeToType;
4077  assert(FD && "no conversion function for user-defined conversion seq");
4078  if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) {
4079  CastKind = CK_UserDefinedConversion;
4080 
4081  // If the user-defined conversion is specified by a conversion function,
4082  // the initial standard conversion sequence converts the source type to
4083  // the implicit object parameter of the conversion function.
4084  BeforeToType = Context.getTagDeclType(Conv->getParent());
4085  } else {
4086  const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD);
4087  CastKind = CK_ConstructorConversion;
4088  // Do no conversion if dealing with ... for the first conversion.
4089  if (!ICS.UserDefined.EllipsisConversion) {
4090  // If the user-defined conversion is specified by a constructor, the
4091  // initial standard conversion sequence converts the source type to
4092  // the type required by the argument of the constructor
4093  BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType();
4094  }
4095  }
4096  // Watch out for ellipsis conversion.
4097  if (!ICS.UserDefined.EllipsisConversion) {
4098  ExprResult Res =
4099  PerformImplicitConversion(From, BeforeToType,
4101  CCK);
4102  if (Res.isInvalid())
4103  return ExprError();
4104  From = Res.get();
4105  }
4106 
4107  ExprResult CastArg = BuildCXXCastArgument(
4108  *this, From->getBeginLoc(), ToType.getNonReferenceType(), CastKind,
4109  cast<CXXMethodDecl>(FD), ICS.UserDefined.FoundConversionFunction,
4111 
4112  if (CastArg.isInvalid())
4113  return ExprError();
4114 
4115  From = CastArg.get();
4116 
4117  // C++ [over.match.oper]p7:
4118  // [...] the second standard conversion sequence of a user-defined
4119  // conversion sequence is not applied.
4120  if (CCK == CCK_ForBuiltinOverloadedOp)
4121  return From;
4122 
4123  return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
4124  AA_Converting, CCK);
4125  }
4126 
4128  ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(),
4129  PDiag(diag::err_typecheck_ambiguous_condition)
4130  << From->getSourceRange());
4131  return ExprError();
4132 
4134  llvm_unreachable("Cannot perform an ellipsis conversion");
4135 
4137  Sema::AssignConvertType ConvTy =
4138  CheckAssignmentConstraints(From->getExprLoc(), ToType, From->getType());
4139  bool Diagnosed = DiagnoseAssignmentResult(
4140  ConvTy == Compatible ? Incompatible : ConvTy, From->getExprLoc(),
4141  ToType, From->getType(), From, Action);
4142  assert(Diagnosed && "failed to diagnose bad conversion"); (void)Diagnosed;
4143  return ExprError();
4144  }
4145 
4146  // Everything went well.
4147  return From;
4148 }
4149 
4150 /// PerformImplicitConversion - Perform an implicit conversion of the
4151 /// expression From to the type ToType by following the standard
4152 /// conversion sequence SCS. Returns the converted
4153 /// expression. Flavor is the context in which we're performing this
4154 /// conversion, for use in error messages.
4155 ExprResult
4157  const StandardConversionSequence& SCS,
4158  AssignmentAction Action,
4159  CheckedConversionKind CCK) {
4160  bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast);
4161 
4162  // Overall FIXME: we are recomputing too many types here and doing far too
4163  // much extra work. What this means is that we need to keep track of more
4164  // information that is computed when we try the implicit conversion initially,
4165  // so that we don't need to recompute anything here.
4166  QualType FromType = From->getType();
4167 
4168  if (SCS.CopyConstructor) {
4169  // FIXME: When can ToType be a reference type?
4170  assert(!ToType->isReferenceType());
4171  if (SCS.Second == ICK_Derived_To_Base) {
4172  SmallVector<Expr*, 8> ConstructorArgs;
4174  cast<CXXConstructorDecl>(SCS.CopyConstructor), ToType, From,
4175  /*FIXME:ConstructLoc*/ SourceLocation(), ConstructorArgs))
4176  return ExprError();
4177  return BuildCXXConstructExpr(
4178  /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
4180  ConstructorArgs, /*HadMultipleCandidates*/ false,
4181  /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
4183  }
4184  return BuildCXXConstructExpr(
4185  /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
4187  From, /*HadMultipleCandidates*/ false,
4188  /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
4190  }
4191 
4192  // Resolve overloaded function references.
4193  if (Context.hasSameType(FromType, Context.OverloadTy)) {
4194  DeclAccessPair Found;
4196  true, Found);
4197  if (!Fn)
4198  return ExprError();
4199 
4200  if (DiagnoseUseOfDecl(Fn, From->getBeginLoc()))
4201  return ExprError();
4202 
4203  From = FixOverloadedFunctionReference(From, Found, Fn);
4204  FromType = From->getType();
4205  }
4206 
4207  // If we're converting to an atomic type, first convert to the corresponding
4208  // non-atomic type.
4209  QualType ToAtomicType;
4210  if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) {
4211  ToAtomicType = ToType;
4212  ToType = ToAtomic->getValueType();
4213  }
4214 
4215  QualType InitialFromType = FromType;
4216  // Perform the first implicit conversion.
4217  switch (SCS.First) {
4218  case ICK_Identity:
4219  if (const AtomicType *FromAtomic = FromType->getAs<AtomicType>()) {
4220  FromType = FromAtomic->getValueType().getUnqualifiedType();
4221  From = ImplicitCastExpr::Create(Context, FromType, CK_AtomicToNonAtomic,
4222  From, /*BasePath=*/nullptr, VK_PRValue,
4223  FPOptionsOverride());
4224  }
4225  break;
4226 
4227  case ICK_Lvalue_To_Rvalue: {
4228  assert(From->getObjectKind() != OK_ObjCProperty);
4229  ExprResult FromRes = DefaultLvalueConversion(From);
4230  if (FromRes.isInvalid())
4231  return ExprError();
4232 
4233  From = FromRes.get();
4234  FromType = From->getType();
4235  break;
4236  }
4237 
4238  case ICK_Array_To_Pointer:
4239  FromType = Context.getArrayDecayedType(FromType);
4240  From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay, VK_PRValue,
4241  /*BasePath=*/nullptr, CCK)
4242  .get();
4243  break;
4244 
4246  FromType = Context.getPointerType(FromType);
4247  From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay,
4248  VK_PRValue, /*BasePath=*/nullptr, CCK)
4249  .get();
4250  break;
4251 
4252  default:
4253  llvm_unreachable("Improper first standard conversion");
4254  }
4255 
4256  // Perform the second implicit conversion
4257  switch (SCS.Second) {
4258  case ICK_Identity:
4259  // C++ [except.spec]p5:
4260  // [For] assignment to and initialization of pointers to functions,
4261  // pointers to member functions, and references to functions: the
4262  // target entity shall allow at least the exceptions allowed by the
4263  // source value in the assignment or initialization.
4264  switch (Action) {
4265  case AA_Assigning:
4266  case AA_Initializing:
4267  // Note, function argument passing and returning are initialization.
4268  case AA_Passing:
4269  case AA_Returning:
4270  case AA_Sending:
4271  case AA_Passing_CFAudited:
4272  if (CheckExceptionSpecCompatibility(From, ToType))
4273  return ExprError();
4274  break;
4275 
4276  case AA_Casting:
4277  case AA_Converting:
4278  // Casts and implicit conversions are not initialization, so are not
4279  // checked for exception specification mismatches.
4280  break;
4281  }
4282  // Nothing else to do.
4283  break;
4284 
4287  if (ToType->isBooleanType()) {
4288  assert(FromType->castAs<EnumType>()->getDecl()->isFixed() &&
4289  SCS.Second == ICK_Integral_Promotion &&
4290  "only enums with fixed underlying type can promote to bool");
4291  From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean, VK_PRValue,
4292  /*BasePath=*/nullptr, CCK)
4293  .get();
4294  } else {
4295  From = ImpCastExprToType(From, ToType, CK_IntegralCast, VK_PRValue,
4296  /*BasePath=*/nullptr, CCK)
4297  .get();
4298  }
4299  break;
4300 
4303  From = ImpCastExprToType(From, ToType, CK_FloatingCast, VK_PRValue,
4304  /*BasePath=*/nullptr, CCK)
4305  .get();
4306  break;
4307 
4308  case ICK_Complex_Promotion:
4309  case ICK_Complex_Conversion: {
4310  QualType FromEl = From->getType()->castAs<ComplexType>()->getElementType();
4311  QualType ToEl = ToType->castAs<ComplexType>()->getElementType();
4312  CastKind CK;
4313  if (FromEl->isRealFloatingType()) {
4314  if (ToEl->isRealFloatingType())
4315  CK = CK_FloatingComplexCast;
4316  else
4317  CK = CK_FloatingComplexToIntegralComplex;
4318  } else if (ToEl->isRealFloatingType()) {
4319  CK = CK_IntegralComplexToFloatingComplex;
4320  } else {
4321  CK = CK_IntegralComplexCast;
4322  }
4323  From = ImpCastExprToType(From, ToType, CK, VK_PRValue, /*BasePath=*/nullptr,
4324  CCK)
4325  .get();
4326  break;
4327  }
4328 
4329  case ICK_Floating_Integral:
4330  if (ToType->isRealFloatingType())
4331  From = ImpCastExprToType(From, ToType, CK_IntegralToFloating, VK_PRValue,
4332  /*BasePath=*/nullptr, CCK)
4333  .get();
4334  else
4335  From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral, VK_PRValue,
4336  /*BasePath=*/nullptr, CCK)
4337  .get();
4338  break;
4339 
4341  From = ImpCastExprToType(From, ToType, CK_NoOp, From->getValueKind(),
4342  /*BasePath=*/nullptr, CCK).get();
4343  break;
4344 
4346  case ICK_Pointer_Conversion: {
4347  if (SCS.IncompatibleObjC && Action != AA_Casting) {
4348  // Diagnose incompatible Objective-C conversions
4349  if (Action == AA_Initializing || Action == AA_Assigning)
4350  Diag(From->getBeginLoc(),
4351  diag::ext_typecheck_convert_incompatible_pointer)
4352  << ToType << From->getType() << Action << From->getSourceRange()
4353  << 0;
4354  else
4355  Diag(From->getBeginLoc(),
4356  diag::ext_typecheck_convert_incompatible_pointer)
4357  << From->getType() << ToType << Action << From->getSourceRange()
4358  << 0;
4359 
4360  if (From->getType()->isObjCObjectPointerType() &&
4361  ToType->isObjCObjectPointerType())
4363  } else if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
4365  From->getType())) {
4366  if (Action == AA_Initializing)
4367  Diag(From->getBeginLoc(), diag::err_arc_weak_unavailable_assign);
4368  else
4369  Diag(From->getBeginLoc(), diag::err_arc_convesion_of_weak_unavailable)
4370  << (Action == AA_Casting) << From->getType() << ToType
4371  << From->getSourceRange();
4372  }
4373 
4374  // Defer address space conversion to the third conversion.
4375  QualType FromPteeType = From->getType()->getPointeeType();
4376  QualType ToPteeType = ToType->getPointeeType();
4377  QualType NewToType = ToType;
4378  if (!FromPteeType.isNull() && !ToPteeType.isNull() &&
4379  FromPteeType.getAddressSpace() != ToPteeType.getAddressSpace()) {
4380  NewToType = Context.removeAddrSpaceQualType(ToPteeType);
4381  NewToType = Context.getAddrSpaceQualType(NewToType,
4382  FromPteeType.getAddressSpace());
4383  if (ToType->isObjCObjectPointerType())
4384  NewToType = Context.getObjCObjectPointerType(NewToType);
4385  else if (ToType->isBlockPointerType())
4386  NewToType = Context.getBlockPointerType(NewToType);
4387  else
4388  NewToType = Context.getPointerType(NewToType);
4389  }
4390 
4391  CastKind Kind;
4392  CXXCastPath BasePath;
4393  if (CheckPointerConversion(From, NewToType, Kind, BasePath, CStyle))
4394  return ExprError();
4395 
4396  // Make sure we extend blocks if necessary.
4397  // FIXME: doing this here is really ugly.
4398  if (Kind == CK_BlockPointerToObjCPointerCast) {
4399  ExprResult E = From;
4401  From = E.get();
4402  }
4404  CheckObjCConversion(SourceRange(), NewToType, From, CCK);
4405  From = ImpCastExprToType(From, NewToType, Kind, VK_PRValue, &BasePath, CCK)
4406  .get();
4407  break;
4408  }
4409 
4410  case ICK_Pointer_Member: {
4411  CastKind Kind;
4412  CXXCastPath BasePath;
4413  if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle))
4414  return ExprError();
4415  if (CheckExceptionSpecCompatibility(From, ToType))
4416  return ExprError();
4417 
4418  // We may not have been able to figure out what this member pointer resolved
4419  // to up until this exact point. Attempt to lock-in it's inheritance model.
4421  (void)isCompleteType(From->getExprLoc(), From->getType());
4422  (void)isCompleteType(From->getExprLoc(), ToType);
4423  }
4424 
4425  From =
4426  ImpCastExprToType(From, ToType, Kind, VK_PRValue, &BasePath, CCK).get();
4427  break;
4428  }
4429 
4431  // Perform half-to-boolean conversion via float.
4432  if (From->getType()->isHalfType()) {
4433  From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).get();
4434  FromType = Context.FloatTy;
4435  }
4436 
4437  From = ImpCastExprToType(From, Context.BoolTy,
4439  /*BasePath=*/nullptr, CCK)
4440  .get();
4441  break;
4442 
4443  case ICK_Derived_To_Base: {
4444  CXXCastPath BasePath;
4446  From->getType(), ToType.getNonReferenceType(), From->getBeginLoc(),
4447  From->getSourceRange(), &BasePath, CStyle))
4448  return ExprError();
4449 
4450  From = ImpCastExprToType(From, ToType.getNonReferenceType(),
4451  CK_DerivedToBase, From->getValueKind(),
4452  &BasePath, CCK).get();
4453  break;
4454  }
4455 
4456  case ICK_Vector_Conversion:
4457  From = ImpCastExprToType(From, ToType, CK_BitCast, VK_PRValue,
4458  /*BasePath=*/nullptr, CCK)
4459  .get();
4460  break;
4461 
4463  From = ImpCastExprToType(From, ToType, CK_BitCast, VK_PRValue,
4464  /*BasePath=*/nullptr, CCK)
4465  .get();
4466  break;
4467 
4468  case ICK_Vector_Splat: {
4469  // Vector splat from any arithmetic type to a vector.
4470  Expr *Elem = prepareVectorSplat(ToType, From).get();
4471  From = ImpCastExprToType(Elem, ToType, CK_VectorSplat, VK_PRValue,
4472  /*BasePath=*/nullptr, CCK)
4473  .get();
4474  break;
4475  }
4476 
4477  case ICK_Complex_Real:
4478  // Case 1. x -> _Complex y
4479  if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) {
4480  QualType ElType = ToComplex->getElementType();
4481  bool isFloatingComplex = ElType->isRealFloatingType();
4482 
4483  // x -> y
4484  if (Context.hasSameUnqualifiedType(ElType, From->getType())) {
4485  // do nothing
4486  } else if (From->getType()->isRealFloatingType()) {
4487  From = ImpCastExprToType(From, ElType,
4488  isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).get();
4489  } else {
4490  assert(From->getType()->isIntegerType());
4491  From = ImpCastExprToType(From, ElType,
4492  isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).get();
4493  }
4494  // y -> _Complex y
4495  From = ImpCastExprToType(From, ToType,
4496  isFloatingComplex ? CK_FloatingRealToComplex
4497  : CK_IntegralRealToComplex).get();
4498 
4499  // Case 2. _Complex x -> y
4500  } else {
4501  auto *FromComplex = From->getType()->castAs<ComplexType>();
4502  QualType ElType = FromComplex->getElementType();
4503  bool isFloatingComplex = ElType->isRealFloatingType();
4504 
4505  // _Complex x -> x
4506  From = ImpCastExprToType(From, ElType,
4507  isFloatingComplex ? CK_FloatingComplexToReal
4508  : CK_IntegralComplexToReal,
4509  VK_PRValue, /*BasePath=*/nullptr, CCK)
4510  .get();
4511 
4512  // x -> y
4513  if (Context.hasSameUnqualifiedType(ElType, ToType)) {
4514  // do nothing
4515  } else if (ToType->isRealFloatingType()) {
4516  From = ImpCastExprToType(From, ToType,
4517  isFloatingComplex ? CK_FloatingCast
4518  : CK_IntegralToFloating,
4519  VK_PRValue, /*BasePath=*/nullptr, CCK)
4520  .get();
4521  } else {
4522  assert(ToType->isIntegerType());
4523  From = ImpCastExprToType(From, ToType,
4524  isFloatingComplex ? CK_FloatingToIntegral
4525  : CK_IntegralCast,
4526  VK_PRValue, /*BasePath=*/nullptr, CCK)
4527  .get();
4528  }
4529  }
4530  break;
4531 
4533  LangAS AddrSpaceL =
4534  ToType->castAs<BlockPointerType>()->getPointeeType().getAddressSpace();
4535  LangAS AddrSpaceR =
4536  FromType->castAs<BlockPointerType>()->getPointeeType().getAddressSpace();
4537  assert(Qualifiers::isAddressSpaceSupersetOf(AddrSpaceL, AddrSpaceR) &&
4538  "Invalid cast");
4539  CastKind Kind =
4540  AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
4541  From = ImpCastExprToType(From, ToType.getUnqualifiedType(), Kind,
4542  VK_PRValue, /*BasePath=*/nullptr, CCK)
4543  .get();
4544  break;
4545  }
4546 
4548  ExprResult FromRes = From;
4549  Sema::AssignConvertType ConvTy =
4551  if (FromRes.isInvalid())
4552  return ExprError();
4553  From = FromRes.get();
4554  assert ((ConvTy == Sema::Compatible) &&
4555  "Improper transparent union conversion");
4556  (void)ConvTy;
4557  break;
4558  }
4559 
4562  From = ImpCastExprToType(From, ToType,
4563  CK_ZeroToOCLOpaqueType,
4564  From->getValueKind()).get();
4565  break;
4566 
4567  case ICK_Lvalue_To_Rvalue:
4568  case ICK_Array_To_Pointer:
4571  case ICK_Qualification:
4573  case ICK_C_Only_Conversion:
4575  llvm_unreachable("Improper second standard conversion");
4576  }
4577 
4578  switch (SCS.Third) {
4579  case ICK_Identity:
4580  // Nothing to do.
4581  break;
4582 
4584  // If both sides are functions (or pointers/references to them), there could
4585  // be incompatible exception declarations.
4586  if (CheckExceptionSpecCompatibility(From, ToType))
4587  return ExprError();
4588 
4589  From = ImpCastExprToType(From, ToType, CK_NoOp, VK_PRValue,
4590  /*BasePath=*/nullptr, CCK)
4591  .get();
4592  break;
4593 
4594  case ICK_Qualification: {
4595  ExprValueKind VK = From->getValueKind();
4596  CastKind CK = CK_NoOp;
4597 
4598  if (ToType->isReferenceType() &&
4599  ToType->getPointeeType().getAddressSpace() !=
4600  From->getType().getAddressSpace())
4601  CK = CK_AddressSpaceConversion;
4602 
4603  if (ToType->isPointerType() &&
4604  ToType->getPointeeType().getAddressSpace() !=
4605  From->getType()->getPointeeType().getAddressSpace())
4606  CK = CK_AddressSpaceConversion;
4607 
4608  From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context), CK, VK,
4609  /*BasePath=*/nullptr, CCK)
4610  .get();
4611 
4613  !getLangOpts().WritableStrings) {
4614  Diag(From->getBeginLoc(),
4616  ? diag::ext_deprecated_string_literal_conversion
4617  : diag::warn_deprecated_string_literal_conversion)
4618  << ToType.getNonReferenceType();
4619  }
4620 
4621  break;
4622  }
4623 
4624  default:
4625  llvm_unreachable("Improper third standard conversion");
4626  }
4627 
4628  // If this conversion sequence involved a scalar -> atomic conversion, perform
4629  // that conversion now.
4630  if (!ToAtomicType.isNull()) {
4631  assert(Context.hasSameType(
4632  ToAtomicType->castAs<AtomicType>()->getValueType(), From->getType()));
4633  From = ImpCastExprToType(From, ToAtomicType, CK_NonAtomicToAtomic,
4634  VK_PRValue, nullptr, CCK)
4635  .get();
4636  }
4637 
4638  // Materialize a temporary if we're implicitly converting to a reference
4639  // type. This is not required by the C++ rules but is necessary to maintain
4640  // AST invariants.
4641  if (ToType->isReferenceType() && From->isPRValue()) {
4643  if (Res.isInvalid())
4644  return ExprError();
4645  From = Res.get();
4646  }
4647 
4648  // If this conversion sequence succeeded and involved implicitly converting a
4649  // _Nullable type to a _Nonnull one, complain.
4650  if (!isCast(CCK))
4651  diagnoseNullableToNonnullConversion(ToType, InitialFromType,
4652  From->getBeginLoc());
4653 
4654  return From;
4655 }
4656 
4657 /// Check the completeness of a type in a unary type trait.
4658 ///
4659 /// If the particular type trait requires a complete type, tries to complete
4660 /// it. If completing the type fails, a diagnostic is emitted and false
4661 /// returned. If completing the type succeeds or no completion was required,
4662 /// returns true.
4664  SourceLocation Loc,
4665  QualType ArgTy) {
4666  // C++0x [meta.unary.prop]p3:
4667  // For all of the class templates X declared in this Clause, instantiating
4668  // that template with a template argument that is a class template
4669  // specialization may result in the implicit instantiation of the template
4670  // argument if and only if the semantics of X require that the argument
4671  // must be a complete type.
4672  // We apply this rule to all the type trait expressions used to implement
4673  // these class templates. We also try to follow any GCC documented behavior
4674  // in these expressions to ensure portability of standard libraries.
4675  switch (UTT) {
4676  default: llvm_unreachable("not a UTT");
4677  // is_complete_type somewhat obviously cannot require a complete type.
4678  case UTT_IsCompleteType:
4679  // Fall-through
4680 
4681  // These traits are modeled on the type predicates in C++0x
4682  // [meta.unary.cat] and [meta.unary.comp]. They are not specified as
4683  // requiring a complete type, as whether or not they return true cannot be
4684  // impacted by the completeness of the type.
4685  case UTT_IsVoid:
4686  case UTT_IsIntegral:
4687  case UTT_IsFloatingPoint:
4688  case UTT_IsArray:
4689  case UTT_IsPointer:
4690  case UTT_IsLvalueReference:
4691  case UTT_IsRvalueReference:
4692  case UTT_IsMemberFunctionPointer:
4693  case UTT_IsMemberObjectPointer:
4694  case UTT_IsEnum:
4695  case UTT_IsUnion:
4696  case UTT_IsClass:
4697  case UTT_IsFunction:
4698  case UTT_IsReference:
4699  case UTT_IsArithmetic:
4700  case UTT_IsFundamental:
4701  case UTT_IsObject:
4702  case UTT_IsScalar:
4703  case UTT_IsCompound:
4704  case UTT_IsMemberPointer:
4705  // Fall-through
4706 
4707  // These traits are modeled on type predicates in C++0x [meta.unary.prop]
4708  // which requires some of its traits to have the complete type. However,
4709  // the completeness of the type cannot impact these traits' semantics, and
4710  // so they don't require it. This matches the comments on these traits in
4711  // Table 49.
4712  case UTT_IsConst:
4713  case UTT_IsVolatile:
4714  case UTT_IsSigned:
4715  case UTT_IsUnsigned:
4716 
4717  // This type trait always returns false, checking the type is moot.
4718  case UTT_IsInterfaceClass:
4719  return true;
4720 
4721  // C++14 [meta.unary.prop]:
4722  // If T is a non-union class type, T shall be a complete type.
4723  case UTT_IsEmpty:
4724  case UTT_IsPolymorphic:
4725  case UTT_IsAbstract:
4726  if (const auto *RD = ArgTy->getAsCXXRecordDecl())
4727  if (!RD->isUnion())
4728  return !S.RequireCompleteType(
4729  Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4730  return true;
4731 
4732  // C++14 [meta.unary.prop]:
4733  // If T is a class type, T shall be a complete type.
4734  case UTT_IsFinal:
4735  case UTT_IsSealed:
4736  if (ArgTy->getAsCXXRecordDecl())
4737  return !S.RequireCompleteType(
4738  Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4739  return true;
4740 
4741  // C++1z [meta.unary.prop]:
4742  // remove_all_extents_t<T> shall be a complete type or cv void.
4743  case UTT_IsAggregate:
4744  case UTT_IsTrivial:
4745  case UTT_IsTriviallyCopyable:
4746  case UTT_IsStandardLayout:
4747  case UTT_IsPOD:
4748  case UTT_IsLiteral:
4749  // Per the GCC type traits documentation, T shall be a complete type, cv void,
4750  // or an array of unknown bound. But GCC actually imposes the same constraints
4751  // as above.
4752  case UTT_HasNothrowAssign:
4753  case UTT_HasNothrowMoveAssign:
4754  case UTT_HasNothrowConstructor:
4755  case UTT_HasNothrowCopy:
4756  case UTT_HasTrivialAssign:
4757  case UTT_HasTrivialMoveAssign:
4758  case UTT_HasTrivialDefaultConstructor:
4759  case UTT_HasTrivialMoveConstructor:
4760  case UTT_HasTrivialCopy:
4761  case UTT_HasTrivialDestructor:
4762  case UTT_HasVirtualDestructor:
4763  ArgTy = QualType(ArgTy->getBaseElementTypeUnsafe(), 0);
4764  LLVM_FALLTHROUGH;
4765 
4766  // C++1z [meta.unary.prop]:
4767  // T shall be a complete type, cv void, or an array of unknown bound.
4768  case UTT_IsDestructible:
4769  case UTT_IsNothrowDestructible:
4770  case UTT_IsTriviallyDestructible:
4771  case UTT_HasUniqueObjectRepresentations:
4772  if (ArgTy->isIncompleteArrayType() || ArgTy->isVoidType())
4773  return true;
4774 
4775  return !S.RequireCompleteType(
4776  Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4777  }
4778 }
4779 
4781  Sema &Self, SourceLocation KeyLoc, ASTContext &C,
4782  bool (CXXRecordDecl::*HasTrivial)() const,
4783  bool (CXXRecordDecl::*HasNonTrivial)() const,
4784  bool (CXXMethodDecl::*IsDesiredOp)() const)
4785 {
4786  CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
4787  if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)())
4788  return true;
4789 
4790  DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op);
4791  DeclarationNameInfo NameInfo(Name, KeyLoc);
4792  LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName);
4793  if (Self.LookupQualifiedName(Res, RD)) {
4794  bool FoundOperator = false;
4795  Res.suppressDiagnostics();
4796  for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end();
4797  Op != OpEnd; ++Op) {
4798  if (isa<FunctionTemplateDecl>(*Op))
4799  continue;
4800 
4801  CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op);
4802  if((Operator->*IsDesiredOp)()) {
4803  FoundOperator = true;
4804  auto *CPT = Operator->getType()->castAs<FunctionProtoType>();
4805  CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4806  if (!CPT || !CPT->isNothrow())
4807  return false;
4808  }
4809  }
4810  return FoundOperator;
4811  }
4812  return false;
4813 }
4814 
4815 static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
4816  SourceLocation KeyLoc, QualType T) {
4817  assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
4818 
4819  ASTContext &C = Self.Context;
4820  switch(UTT) {
4821  default: llvm_unreachable("not a UTT");
4822  // Type trait expressions corresponding to the primary type category
4823  // predicates in C++0x [meta.unary.cat].
4824  case UTT_IsVoid:
4825  return T->isVoidType();
4826  case UTT_IsIntegral:
4827  return T->isIntegralType(C);
4828  case UTT_IsFloatingPoint:
4829  return T->isFloatingType();
4830  case UTT_IsArray:
4831  return T->isArrayType();
4832  case UTT_IsPointer:
4833  return T->isAnyPointerType();
4834  case UTT_IsLvalueReference:
4835  return T->isLValueReferenceType();
4836  case UTT_IsRvalueReference:
4837  return T->isRValueReferenceType();
4838  case UTT_IsMemberFunctionPointer:
4839  return T->isMemberFunctionPointerType();
4840  case UTT_IsMemberObjectPointer:
4841  return T->isMemberDataPointerType();
4842  case UTT_IsEnum:
4843  return T->isEnumeralType();
4844  case UTT_IsUnion:
4845  return T->isUnionType();
4846  case UTT_IsClass:
4847  return T->isClassType() || T->isStructureType() || T->isInterfaceType();
4848  case UTT_IsFunction:
4849  return T->isFunctionType();
4850 
4851  // Type trait expressions which correspond to the convenient composition
4852  // predicates in C++0x [meta.unary.comp].
4853  case UTT_IsReference:
4854  return T->isReferenceType();
4855  case UTT_IsArithmetic:
4856  return T->isArithmeticType() && !T->isEnumeralType();
4857  case UTT_IsFundamental:
4858  return T->isFundamentalType();
4859  case UTT_IsObject:
4860  return T->isObjectType();
4861  case UTT_IsScalar:
4862  // Note: semantic analysis depends on Objective-C lifetime types to be
4863  // considered scalar types. However, such types do not actually behave
4864  // like scalar types at run time (since they may require retain/release
4865  // operations), so we report them as non-scalar.
4866  if (T->isObjCLifetimeType()) {
4867  switch (T.getObjCLifetime()) {
4868  case Qualifiers::OCL_None:
4870  return true;
4871 
4873  case Qualifiers::OCL_Weak:
4875  return false;
4876  }
4877  }
4878 
4879  return T->isScalarType();
4880  case UTT_IsCompound:
4881  return T->isCompoundType();
4882  case UTT_IsMemberPointer:
4883  return T->isMemberPointerType();
4884 
4885  // Type trait expressions which correspond to the type property predicates
4886  // in C++0x [meta.unary.prop].
4887  case UTT_IsConst:
4888  return T.isConstQualified();
4889  case UTT_IsVolatile:
4890  return T.isVolatileQualified();
4891  case UTT_IsTrivial:
4892  return T.isTrivialType(C);
4893  case UTT_IsTriviallyCopyable:
4894  return T.isTriviallyCopyableType(C);
4895  case UTT_IsStandardLayout:
4896  return T->isStandardLayoutType();
4897  case UTT_IsPOD:
4898  return T.isPODType(C);
4899  case UTT_IsLiteral:
4900  return T->isLiteralType(C);
4901  case UTT_IsEmpty:
4902  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4903  return !RD->isUnion() && RD->isEmpty();
4904  return false;
4905  case UTT_IsPolymorphic:
4906  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4907  return !RD->isUnion() && RD->isPolymorphic();
4908  return false;
4909  case UTT_IsAbstract:
4910  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4911  return !RD->isUnion() && RD->isAbstract();
4912  return false;
4913  case UTT_IsAggregate:
4914  // Report vector extensions and complex types as aggregates because they
4915  // support aggregate initialization. GCC mirrors this behavior for vectors
4916  // but not _Complex.
4917  return T->isAggregateType() || T->isVectorType() || T->isExtVectorType() ||
4918  T->isAnyComplexType();
4919  // __is_interface_class only returns true when CL is invoked in /CLR mode and
4920  // even then only when it is used with the 'interface struct ...' syntax
4921  // Clang doesn't support /CLR which makes this type trait moot.
4922  case UTT_IsInterfaceClass:
4923  return false;
4924  case UTT_IsFinal:
4925  case UTT_IsSealed:
4926  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4927  return RD->hasAttr<FinalAttr>();
4928  return false;
4929  case UTT_IsSigned:
4930  // Enum types should always return false.
4931  // Floating points should always return true.
4932  return T->isFloatingType() ||
4933  (T->isSignedIntegerType() && !T->isEnumeralType());
4934  case UTT_IsUnsigned:
4935  // Enum types should always return false.
4936  return T->isUnsignedIntegerType() && !T->isEnumeralType();
4937 
4938  // Type trait expressions which query classes regarding their construction,
4939  // destruction, and copying. Rather than being based directly on the
4940  // related type predicates in the standard, they are specified by both
4941  // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those
4942  // specifications.
4943  //
4944  // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
4945  // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4946  //
4947  // Note that these builtins do not behave as documented in g++: if a class
4948  // has both a trivial and a non-trivial special member of a particular kind,
4949  // they return false! For now, we emulate this behavior.
4950  // FIXME: This appears to be a g++ bug: more complex cases reveal that it
4951  // does not correctly compute triviality in the presence of multiple special
4952  // members of the same kind. Revisit this once the g++ bug is fixed.
4953  case UTT_HasTrivialDefaultConstructor:
4954  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4955  // If __is_pod (type) is true then the trait is true, else if type is
4956  // a cv class or union type (or array thereof) with a trivial default
4957  // constructor ([class.ctor]) then the trait is true, else it is false.
4958  if (T.isPODType(C))
4959  return true;
4960  if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4961  return RD->hasTrivialDefaultConstructor() &&
4963  return false;
4964  case UTT_HasTrivialMoveConstructor:
4965  // This trait is implemented by MSVC 2012 and needed to parse the
4966  // standard library headers. Specifically this is used as the logic
4967  // behind std::is_trivially_move_constructible (20.9.4.3).
4968  if (T.isPODType(C))
4969  return true;
4970  if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4972  return false;
4973  case UTT_HasTrivialCopy:
4974  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4975  // If __is_pod (type) is true or type is a reference type then
4976  // the trait is true, else if type is a cv class or union type
4977  // with a trivial copy constructor ([class.copy]) then the trait
4978  // is true, else it is false.
4979  if (T.isPODType(C) || T->isReferenceType())
4980  return true;
4981  if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4982  return RD->hasTrivialCopyConstructor() &&
4984  return false;
4985  case UTT_HasTrivialMoveAssign:
4986  // This trait is implemented by MSVC 2012 and needed to parse the
4987  // standard library headers. Specifically it is used as the logic
4988  // behind std::is_trivially_move_assignable (20.9.4.3)
4989  if (T.isPODType(C))
4990  return true;
4991  if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4993  return false;
4994  case UTT_HasTrivialAssign:
4995  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4996  // If type is const qualified or is a reference type then the
4997  // trait is false. Otherwise if __is_pod (type) is true then the
4998  // trait is true, else if type is a cv class or union type with
4999  // a trivial copy assignment ([class.copy]) then the trait is
5000  // true, else it is false.
5001  // Note: the const and reference restrictions are interesting,
5002  // given that const and reference members don't prevent a class
5003  // from having a trivial copy assignment operator (but do cause
5004  // errors if the copy assignment operator is actually used, q.v.
5005  // [class.copy]p12).
5006 
5007  if (T.isConstQualified())
5008  return false;
5009  if (T.isPODType(C))
5010  return true;
5011  if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5012  return RD->hasTrivialCopyAssignment() &&
5014  return false;
5015  case UTT_IsDestructible:
5016  case UTT_IsTriviallyDestructible:
5017  case UTT_IsNothrowDestructible:
5018  // C++14 [meta.unary.prop]:
5019  // For reference types, is_destructible<T>::value is true.
5020  if (T->isReferenceType())
5021  return true;
5022 
5023  // Objective-C++ ARC: autorelease types don't require destruction.
5024  if (T->isObjCLifetimeType() &&
5026  return true;
5027 
5028  // C++14 [meta.unary.prop]:
5029  // For incomplete types and function types, is_destructible<T>::value is
5030  // false.
5031  if (T->isIncompleteType() || T->isFunctionType())
5032  return false;
5033 
5034  // A type that requires destruction (via a non-trivial destructor or ARC
5035  // lifetime semantics) is not trivially-destructible.
5036  if (UTT == UTT_IsTriviallyDestructible && T.isDestructedType())
5037  return false;
5038 
5039  // C++14 [meta.unary.prop]:
5040  // For object types and given U equal to remove_all_extents_t<T>, if the
5041  // expression std::declval<U&>().~U() is well-formed when treated as an
5042  // unevaluated operand (Clause 5), then is_destructible<T>::value is true
5043  if (auto *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
5044  CXXDestructorDecl *Destructor = Self.LookupDestructor(RD);
5045  if (!Destructor)
5046  return false;
5047  // C++14 [dcl.fct.def.delete]p2:
5048  // A program that refers to a deleted function implicitly or
5049  // explicitly, other than to declare it, is ill-formed.
5050  if (Destructor->isDeleted())
5051  return false;
5052  if (C.getLangOpts().AccessControl && Destructor->getAccess() != AS_public)
5053  return false;
5054  if (UTT == UTT_IsNothrowDestructible) {
5055  auto *CPT = Destructor->getType()->castAs<FunctionProtoType>();
5056  CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
5057  if (!CPT || !CPT->isNothrow())
5058  return false;
5059  }
5060  }
5061  return true;
5062 
5063  case UTT_HasTrivialDestructor:
5064  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
5065  // If __is_pod (type) is true or type is a reference type
5066  // then the trait is true, else if type is a cv class or union
5067  // type (or array thereof) with a trivial destructor
5068  // ([class.dtor]) then the trait is true, else it is
5069  // false.
5070  if (T.isPODType(C) || T->isReferenceType())
5071  return true;
5072 
5073  // Objective-C++ ARC: autorelease types don't require destruction.
5074  if (T->isObjCLifetimeType() &&
5076  return true;
5077 
5078  if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
5079  return RD->hasTrivialDestructor();
5080  return false;
5081  // TODO: Propagate nothrowness for implicitly declared special members.
5082  case UTT_HasNothrowAssign:
5083  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5084  // If type is const qualified or is a reference type then the
5085  // trait is false. Otherwise if __has_trivial_assign (type)
5086  // is true then the trait is true, else if type is a cv class
5087  // or union type with copy assignment operators that are known
5088  // not to throw an exception then the trait is true, else it is
5089  // false.
5090  if (C.getBaseElementType(T).isConstQualified())
5091  return false;
5092  if (T->isReferenceType())
5093  return false;
5094  if (T.isPODType(C) || T->isObjCLifetimeType())
5095  return true;
5096 
5097  if (const RecordType *RT = T->getAs<RecordType>())
5098  return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
5102  return false;
5103  case UTT_HasNothrowMoveAssign:
5104  // This trait is implemented by MSVC 2012 and needed to parse the
5105  // standard library headers. Specifically this is used as the logic
5106  // behind std::is_nothrow_move_assignable (20.9.4.3).
5107  if (T.isPODType(C))
5108  return true;
5109 
5110  if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>())
5111  return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
5115  return false;
5116  case UTT_HasNothrowCopy:
5117  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5118  // If __has_trivial_copy (type) is true then the trait is true, else
5119  // if type is a cv class or union type with copy constructors that are
5120  // known not to throw an exception then the trait is true, else it is
5121  // false.
5122  if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
5123  return true;
5124  if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
5125  if (RD->hasTrivialCopyConstructor() &&
5127  return true;
5128 
5129  bool FoundConstructor = false;
5130  unsigned FoundTQs;
5131  for (const auto *ND : Self.LookupConstructors(RD)) {
5132  // A template constructor is never a copy constructor.
5133  // FIXME: However, it may actually be selected at the actual overload
5134  // resolution point.
5135  if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
5136  continue;
5137  // UsingDecl itself is not a constructor
5138  if (isa<UsingDecl>(ND))
5139  continue;
5140  auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
5141  if (Constructor->isCopyConstructor(FoundTQs)) {
5142  FoundConstructor = true;
5143  auto *CPT = Constructor->getType()->castAs<FunctionProtoType>();
5144  CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
5145  if (!CPT)
5146  return false;
5147  // TODO: check whether evaluating default arguments can throw.
5148  // For now, we'll be conservative and assume that they can throw.
5149  if (!CPT->isNothrow() || CPT->getNumParams() > 1)
5150  return false;
5151  }
5152  }
5153 
5154  return FoundConstructor;
5155  }
5156  return false;
5157  case UTT_HasNothrowConstructor:
5158  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
5159  // If __has_trivial_constructor (type) is true then the trait is
5160  // true, else if type is a cv class or union type (or array
5161  // thereof) with a default constructor that is known not to
5162  // throw an exception then the trait is true, else it is false.
5163  if (T.isPODType(C) || T->isObjCLifetimeType())
5164  return true;
5165  if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
5166  if (RD->hasTrivialDefaultConstructor() &&
5168  return true;
5169 
5170  bool FoundConstructor = false;
5171  for (const auto *ND : Self.LookupConstructors(RD)) {
5172  // FIXME: In C++0x, a constructor template can be a default constructor.
5173  if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
5174  continue;
5175  // UsingDecl itself is not a constructor
5176  if (isa<UsingDecl>(ND))
5177  continue;
5178  auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
5179  if (Constructor->isDefaultConstructor()) {
5180  FoundConstructor = true;
5181  auto *CPT = Constructor->getType()->castAs<FunctionProtoType>();
5182  CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
5183  if (!CPT)
5184  return false;
5185  // FIXME: check whether evaluating default arguments can throw.
5186  // For now, we'll be conservative and assume that they can throw.
5187  if (!CPT->isNothrow() || CPT->getNumParams() > 0)
5188  return false;
5189  }
5190  }
5191  return FoundConstructor;
5192  }
5193  return false;
5194  case UTT_HasVirtualDestructor:
5195  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
5196  // If type is a class type with a virtual destructor ([class.dtor])
5197  // then the trait is true, else it is false.
5198  if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
5199  if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
5200  return Destructor->isVirtual();
5201  return false;
5202 
5203  // These type trait expressions are modeled on the specifications for the
5204  // Embarcadero C++0x type trait functions:
5205  // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
5206  case UTT_IsCompleteType:
5207  // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_):
5208  // Returns True if and only if T is a complete type at the point of the
5209  // function call.
5210  return !T->isIncompleteType();
5211  case UTT_HasUniqueObjectRepresentations:
5212  return C.hasUniqueObjectRepresentations(T);
5213  }
5214 }
5215 
5216 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
5217  QualType RhsT, SourceLocation KeyLoc);
5218 
5221  SourceLocation RParenLoc) {
5222  if (Kind <= UTT_Last)
5223  return EvaluateUnaryTypeTrait(S, Kind, KWLoc, Args[0]->getType());
5224 
5225  // Evaluate BTT_ReferenceBindsToTemporary alongside the IsConstructible
5226  // traits to avoid duplication.
5227  if (Kind <= BTT_Last && Kind != BTT_ReferenceBindsToTemporary)
5228  return EvaluateBinaryTypeTrait(S, Kind, Args[0]->getType(),
5229  Args[1]->getType(), RParenLoc);
5230 
5231  switch (Kind) {
5232  case clang::BTT_ReferenceBindsToTemporary:
5233  case clang::TT_IsConstructible:
5234  case clang::TT_IsNothrowConstructible:
5235  case clang::TT_IsTriviallyConstructible: {
5236  // C++11 [meta.unary.prop]:
5237  // is_trivially_constructible is defined as:
5238  //
5239  // is_constructible<T, Args...>::value is true and the variable
5240  // definition for is_constructible, as defined below, is known to call
5241  // no operation that is not trivial.
5242  //
5243  // The predicate condition for a template specialization
5244  // is_constructible<T, Args...> shall be satisfied if and only if the
5245  // following variable definition would be well-formed for some invented
5246  // variable t:
5247  //
5248  // T t(create<Args>()...);
5249  assert(!Args.empty());
5250 
5251  // Precondition: T and all types in the parameter pack Args shall be
5252  // complete types, (possibly cv-qualified) void, or arrays of
5253  // unknown bound.
5254  for (const auto *TSI : Args) {
5255  QualType ArgTy = TSI->getType();
5256  if (ArgTy->isVoidType() || ArgTy->isIncompleteArrayType())
5257  continue;
5258 
5259  if (S.RequireCompleteType(KWLoc, ArgTy,
5260  diag::err_incomplete_type_used_in_type_trait_expr))
5261  return false;
5262  }
5263 
5264  // Make sure the first argument is not incomplete nor a function type.
5265  QualType T = Args[0]->getType();
5266  if (T->isIncompleteType() || T->isFunctionType())
5267  return false;
5268 
5269  // Make sure the first argument is not an abstract type.
5270  CXXRecordDecl *RD = T->getAsCXXRecordDecl();
5271  if (RD && RD->isAbstract())
5272  return false;
5273 
5274  llvm::BumpPtrAllocator OpaqueExprAllocator;
5275  SmallVector<Expr *, 2> ArgExprs;
5276  ArgExprs.reserve(Args.size() - 1);
5277  for (unsigned I = 1, N = Args.size(); I != N; ++I) {
5278  QualType ArgTy = Args[I]->getType();
5279  if (ArgTy->isObjectType() || ArgTy->isFunctionType())
5280  ArgTy = S.Context.getRValueReferenceType(ArgTy);
5281  ArgExprs.push_back(
5282  new (OpaqueExprAllocator.Allocate<OpaqueValueExpr>())
5283  OpaqueValueExpr(Args[I]->getTypeLoc().getBeginLoc(),
5284  ArgTy.getNonLValueExprType(S.Context),
5285  Expr::getValueKindForType(ArgTy)));
5286  }
5287 
5288  // Perform the initialization in an unevaluated context within a SFINAE
5289  // trap at translation unit scope.
5292  Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
5294  InitializedEntity To(
5297  RParenLoc));
5298  InitializationSequence Init(S, To, InitKind, ArgExprs);
5299  if (Init.Failed())
5300  return false;
5301 
5302  ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs);
5303  if (Result.isInvalid() || SFINAE.hasErrorOccurred())
5304  return false;
5305 
5306  if (Kind == clang::TT_IsConstructible)
5307  return true;
5308 
5309  if (Kind == clang::BTT_ReferenceBindsToTemporary) {
5310  if (!T->isReferenceType())
5311  return false;
5312 
5313  return !Init.isDirectReferenceBinding();
5314  }
5315 
5316  if (Kind == clang::TT_IsNothrowConstructible)
5317  return S.canThrow(Result.get()) == CT_Cannot;
5318 
5319  if (Kind == clang::TT_IsTriviallyConstructible) {
5320  // Under Objective-C ARC and Weak, if the destination has non-trivial
5321  // Objective-C lifetime, this is a non-trivial construction.
5323  return false;
5324 
5325  // The initialization succeeded; now make sure there are no non-trivial
5326  // calls.
5327  return !Result.get()->hasNonTrivialCall(S.Context);
5328  }
5329 
5330  llvm_unreachable("unhandled type trait");
5331  return false;
5332  }
5333  default: llvm_unreachable("not a TT");
5334  }
5335 
5336  return false;
5337 }
5338 
5341  SourceLocation RParenLoc) {
5342  QualType ResultType = Context.getLogicalOperationType();
5343 
5345  *this, Kind, KWLoc, Args[0]->getType()))
5346  return ExprError();
5347 
5348  bool Dependent = false;
5349  for (unsigned I = 0, N = Args.size(); I != N; ++I) {
5350  if (Args[I]->getType()->isDependentType()) {
5351  Dependent = true;
5352  break;
5353  }
5354  }
5355 
5356  bool Result = false;
5357  if (!Dependent)
5358  Result = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc);
5359 
5360  return TypeTraitExpr::Create(Context, ResultType, KWLoc, Kind, Args,
5361  RParenLoc, Result);
5362 }
5363 
5365  ArrayRef<ParsedType> Args,
5366  SourceLocation RParenLoc) {
5367  SmallVector<TypeSourceInfo *, 4> ConvertedArgs;
5368  ConvertedArgs.reserve(Args.size());
5369 
5370  for (unsigned I = 0, N = Args.size(); I != N; ++I) {
5371  TypeSourceInfo *TInfo;
5372  QualType T = GetTypeFromParser(Args[I], &TInfo);
5373  if (!TInfo)