clang  10.0.0svn
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 
15 #include "TreeTransform.h"
16 #include "TypeLocBuilder.h"
17 #include "clang/AST/ASTContext.h"
18 #include "clang/AST/ASTLambda.h"
20 #include "clang/AST/CharUnits.h"
21 #include "clang/AST/DeclObjC.h"
22 #include "clang/AST/ExprCXX.h"
23 #include "clang/AST/ExprObjC.h"
25 #include "clang/AST/TypeLoc.h"
28 #include "clang/Basic/TargetInfo.h"
29 #include "clang/Lex/Preprocessor.h"
30 #include "clang/Sema/DeclSpec.h"
32 #include "clang/Sema/Lookup.h"
34 #include "clang/Sema/Scope.h"
35 #include "clang/Sema/ScopeInfo.h"
36 #include "clang/Sema/SemaLambda.h"
38 #include "llvm/ADT/APInt.h"
39 #include "llvm/ADT/STLExtras.h"
40 #include "llvm/Support/ErrorHandling.h"
41 using namespace clang;
42 using namespace sema;
43 
44 /// Handle the result of the special case name lookup for inheriting
45 /// constructor declarations. 'NS::X::X' and 'NS::X<...>::X' are treated as
46 /// constructor names in member using declarations, even if 'X' is not the
47 /// name of the corresponding type.
49  SourceLocation NameLoc,
50  IdentifierInfo &Name) {
51  NestedNameSpecifier *NNS = SS.getScopeRep();
52 
53  // Convert the nested-name-specifier into a type.
54  QualType Type;
55  switch (NNS->getKind()) {
58  Type = QualType(NNS->getAsType(), 0);
59  break;
60 
62  // Strip off the last layer of the nested-name-specifier and build a
63  // typename type for it.
64  assert(NNS->getAsIdentifier() == &Name && "not a constructor name");
65  Type = Context.getDependentNameType(ETK_None, NNS->getPrefix(),
66  NNS->getAsIdentifier());
67  break;
68 
73  llvm_unreachable("Nested name specifier is not a type for inheriting ctor");
74  }
75 
76  // This reference to the type is located entirely at the location of the
77  // final identifier in the qualified-id.
78  return CreateParsedType(Type,
79  Context.getTrivialTypeSourceInfo(Type, NameLoc));
80 }
81 
83  SourceLocation NameLoc,
84  Scope *S, CXXScopeSpec &SS,
85  bool EnteringContext) {
86  CXXRecordDecl *CurClass = getCurrentClass(S, &SS);
87  assert(CurClass && &II == CurClass->getIdentifier() &&
88  "not a constructor name");
89 
90  // When naming a constructor as a member of a dependent context (eg, in a
91  // friend declaration or an inherited constructor declaration), form an
92  // unresolved "typename" type.
93  if (CurClass->isDependentContext() && !EnteringContext && SS.getScopeRep()) {
94  QualType T = Context.getDependentNameType(ETK_None, SS.getScopeRep(), &II);
95  return ParsedType::make(T);
96  }
97 
98  if (SS.isNotEmpty() && RequireCompleteDeclContext(SS, CurClass))
99  return ParsedType();
100 
101  // Find the injected-class-name declaration. Note that we make no attempt to
102  // diagnose cases where the injected-class-name is shadowed: the only
103  // declaration that can validly shadow the injected-class-name is a
104  // non-static data member, and if the class contains both a non-static data
105  // member and a constructor then it is ill-formed (we check that in
106  // CheckCompletedCXXClass).
107  CXXRecordDecl *InjectedClassName = nullptr;
108  for (NamedDecl *ND : CurClass->lookup(&II)) {
109  auto *RD = dyn_cast<CXXRecordDecl>(ND);
110  if (RD && RD->isInjectedClassName()) {
111  InjectedClassName = RD;
112  break;
113  }
114  }
115  if (!InjectedClassName) {
116  if (!CurClass->isInvalidDecl()) {
117  // FIXME: RequireCompleteDeclContext doesn't check dependent contexts
118  // properly. Work around it here for now.
120  diag::err_incomplete_nested_name_spec) << CurClass << SS.getRange();
121  }
122  return ParsedType();
123  }
124 
125  QualType T = Context.getTypeDeclType(InjectedClassName);
126  DiagnoseUseOfDecl(InjectedClassName, NameLoc);
127  MarkAnyDeclReferenced(NameLoc, InjectedClassName, /*OdrUse=*/false);
128 
129  return ParsedType::make(T);
130 }
131 
133  IdentifierInfo &II,
134  SourceLocation NameLoc,
135  Scope *S, CXXScopeSpec &SS,
136  ParsedType ObjectTypePtr,
137  bool EnteringContext) {
138  // Determine where to perform name lookup.
139 
140  // FIXME: This area of the standard is very messy, and the current
141  // wording is rather unclear about which scopes we search for the
142  // destructor name; see core issues 399 and 555. Issue 399 in
143  // particular shows where the current description of destructor name
144  // lookup is completely out of line with existing practice, e.g.,
145  // this appears to be ill-formed:
146  //
147  // namespace N {
148  // template <typename T> struct S {
149  // ~S();
150  // };
151  // }
152  //
153  // void f(N::S<int>* s) {
154  // s->N::S<int>::~S();
155  // }
156  //
157  // See also PR6358 and PR6359.
158  // For this reason, we're currently only doing the C++03 version of this
159  // code; the C++0x version has to wait until we get a proper spec.
160  QualType SearchType;
161  DeclContext *LookupCtx = nullptr;
162  bool isDependent = false;
163  bool LookInScope = false;
164 
165  if (SS.isInvalid())
166  return nullptr;
167 
168  // If we have an object type, it's because we are in a
169  // pseudo-destructor-expression or a member access expression, and
170  // we know what type we're looking for.
171  if (ObjectTypePtr)
172  SearchType = GetTypeFromParser(ObjectTypePtr);
173 
174  if (SS.isSet()) {
175  NestedNameSpecifier *NNS = SS.getScopeRep();
176 
177  bool AlreadySearched = false;
178  bool LookAtPrefix = true;
179  // C++11 [basic.lookup.qual]p6:
180  // If a pseudo-destructor-name (5.2.4) contains a nested-name-specifier,
181  // the type-names are looked up as types in the scope designated by the
182  // nested-name-specifier. Similarly, in a qualified-id of the form:
183  //
184  // nested-name-specifier[opt] class-name :: ~ class-name
185  //
186  // the second class-name is looked up in the same scope as the first.
187  //
188  // Here, we determine whether the code below is permitted to look at the
189  // prefix of the nested-name-specifier.
190  DeclContext *DC = computeDeclContext(SS, EnteringContext);
191  if (DC && DC->isFileContext()) {
192  AlreadySearched = true;
193  LookupCtx = DC;
194  isDependent = false;
195  } else if (DC && isa<CXXRecordDecl>(DC)) {
196  LookAtPrefix = false;
197  LookInScope = true;
198  }
199 
200  // The second case from the C++03 rules quoted further above.
201  NestedNameSpecifier *Prefix = nullptr;
202  if (AlreadySearched) {
203  // Nothing left to do.
204  } else if (LookAtPrefix && (Prefix = NNS->getPrefix())) {
205  CXXScopeSpec PrefixSS;
206  PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data()));
207  LookupCtx = computeDeclContext(PrefixSS, EnteringContext);
208  isDependent = isDependentScopeSpecifier(PrefixSS);
209  } else if (ObjectTypePtr) {
210  LookupCtx = computeDeclContext(SearchType);
211  isDependent = SearchType->isDependentType();
212  } else {
213  LookupCtx = computeDeclContext(SS, EnteringContext);
214  isDependent = LookupCtx && LookupCtx->isDependentContext();
215  }
216  } else if (ObjectTypePtr) {
217  // C++ [basic.lookup.classref]p3:
218  // If the unqualified-id is ~type-name, the type-name is looked up
219  // in the context of the entire postfix-expression. If the type T
220  // of the object expression is of a class type C, the type-name is
221  // also looked up in the scope of class C. At least one of the
222  // lookups shall find a name that refers to (possibly
223  // cv-qualified) T.
224  LookupCtx = computeDeclContext(SearchType);
225  isDependent = SearchType->isDependentType();
226  assert((isDependent || !SearchType->isIncompleteType()) &&
227  "Caller should have completed object type");
228 
229  LookInScope = true;
230  } else {
231  // Perform lookup into the current scope (only).
232  LookInScope = true;
233  }
234 
235  TypeDecl *NonMatchingTypeDecl = nullptr;
236  LookupResult Found(*this, &II, NameLoc, LookupOrdinaryName);
237  for (unsigned Step = 0; Step != 2; ++Step) {
238  // Look for the name first in the computed lookup context (if we
239  // have one) and, if that fails to find a match, in the scope (if
240  // we're allowed to look there).
241  Found.clear();
242  if (Step == 0 && LookupCtx) {
243  if (RequireCompleteDeclContext(SS, LookupCtx))
244  return nullptr;
245  LookupQualifiedName(Found, LookupCtx);
246  } else if (Step == 1 && LookInScope && S) {
247  LookupName(Found, S);
248  } else {
249  continue;
250  }
251 
252  // FIXME: Should we be suppressing ambiguities here?
253  if (Found.isAmbiguous())
254  return nullptr;
255 
256  if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) {
257  QualType T = Context.getTypeDeclType(Type);
258  MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
259 
260  if (SearchType.isNull() || SearchType->isDependentType() ||
261  Context.hasSameUnqualifiedType(T, SearchType)) {
262  // We found our type!
263 
264  return CreateParsedType(T,
265  Context.getTrivialTypeSourceInfo(T, NameLoc));
266  }
267 
268  if (!SearchType.isNull())
269  NonMatchingTypeDecl = Type;
270  }
271 
272  // If the name that we found is a class template name, and it is
273  // the same name as the template name in the last part of the
274  // nested-name-specifier (if present) or the object type, then
275  // this is the destructor for that class.
276  // FIXME: This is a workaround until we get real drafting for core
277  // issue 399, for which there isn't even an obvious direction.
278  if (ClassTemplateDecl *Template = Found.getAsSingle<ClassTemplateDecl>()) {
279  QualType MemberOfType;
280  if (SS.isSet()) {
281  if (DeclContext *Ctx = computeDeclContext(SS, EnteringContext)) {
282  // Figure out the type of the context, if it has one.
283  if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx))
284  MemberOfType = Context.getTypeDeclType(Record);
285  }
286  }
287  if (MemberOfType.isNull())
288  MemberOfType = SearchType;
289 
290  if (MemberOfType.isNull())
291  continue;
292 
293  // We're referring into a class template specialization. If the
294  // class template we found is the same as the template being
295  // specialized, we found what we are looking for.
296  if (const RecordType *Record = MemberOfType->getAs<RecordType>()) {
298  = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) {
299  if (Spec->getSpecializedTemplate()->getCanonicalDecl() ==
300  Template->getCanonicalDecl())
301  return CreateParsedType(
302  MemberOfType,
303  Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
304  }
305 
306  continue;
307  }
308 
309  // We're referring to an unresolved class template
310  // specialization. Determine whether we class template we found
311  // is the same as the template being specialized or, if we don't
312  // know which template is being specialized, that it at least
313  // has the same name.
314  if (const TemplateSpecializationType *SpecType
315  = MemberOfType->getAs<TemplateSpecializationType>()) {
316  TemplateName SpecName = SpecType->getTemplateName();
317 
318  // The class template we found is the same template being
319  // specialized.
320  if (TemplateDecl *SpecTemplate = SpecName.getAsTemplateDecl()) {
321  if (SpecTemplate->getCanonicalDecl() == Template->getCanonicalDecl())
322  return CreateParsedType(
323  MemberOfType,
324  Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
325 
326  continue;
327  }
328 
329  // The class template we found has the same name as the
330  // (dependent) template name being specialized.
331  if (DependentTemplateName *DepTemplate
332  = SpecName.getAsDependentTemplateName()) {
333  if (DepTemplate->isIdentifier() &&
334  DepTemplate->getIdentifier() == Template->getIdentifier())
335  return CreateParsedType(
336  MemberOfType,
337  Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
338 
339  continue;
340  }
341  }
342  }
343  }
344 
345  if (isDependent) {
346  // We didn't find our type, but that's okay: it's dependent
347  // anyway.
348 
349  // FIXME: What if we have no nested-name-specifier?
350  QualType T = CheckTypenameType(ETK_None, SourceLocation(),
351  SS.getWithLocInContext(Context),
352  II, NameLoc);
353  return ParsedType::make(T);
354  }
355 
356  if (NonMatchingTypeDecl) {
357  QualType T = Context.getTypeDeclType(NonMatchingTypeDecl);
358  Diag(NameLoc, diag::err_destructor_expr_type_mismatch)
359  << T << SearchType;
360  Diag(NonMatchingTypeDecl->getLocation(), diag::note_destructor_type_here)
361  << T;
362  } else if (ObjectTypePtr)
363  Diag(NameLoc, diag::err_ident_in_dtor_not_a_type)
364  << &II;
365  else {
366  SemaDiagnosticBuilder DtorDiag = Diag(NameLoc,
367  diag::err_destructor_class_name);
368  if (S) {
369  const DeclContext *Ctx = S->getEntity();
370  if (const CXXRecordDecl *Class = dyn_cast_or_null<CXXRecordDecl>(Ctx))
371  DtorDiag << FixItHint::CreateReplacement(SourceRange(NameLoc),
372  Class->getNameAsString());
373  }
374  }
375 
376  return nullptr;
377 }
378 
380  ParsedType ObjectType) {
382  return nullptr;
383 
385  Diag(DS.getTypeSpecTypeLoc(), diag::err_decltype_auto_invalid);
386  return nullptr;
387  }
388 
389  assert(DS.getTypeSpecType() == DeclSpec::TST_decltype &&
390  "unexpected type in getDestructorType");
391  QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
392 
393  // If we know the type of the object, check that the correct destructor
394  // type was named now; we can give better diagnostics this way.
395  QualType SearchType = GetTypeFromParser(ObjectType);
396  if (!SearchType.isNull() && !SearchType->isDependentType() &&
397  !Context.hasSameUnqualifiedType(T, SearchType)) {
398  Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch)
399  << T << SearchType;
400  return nullptr;
401  }
402 
403  return ParsedType::make(T);
404 }
405 
407  const UnqualifiedId &Name) {
409 
410  if (!SS.isValid())
411  return false;
412 
413  switch (SS.getScopeRep()->getKind()) {
417  // Per C++11 [over.literal]p2, literal operators can only be declared at
418  // namespace scope. Therefore, this unqualified-id cannot name anything.
419  // Reject it early, because we have no AST representation for this in the
420  // case where the scope is dependent.
421  Diag(Name.getBeginLoc(), diag::err_literal_operator_id_outside_namespace)
422  << SS.getScopeRep();
423  return true;
424 
429  return false;
430  }
431 
432  llvm_unreachable("unknown nested name specifier kind");
433 }
434 
435 /// Build a C++ typeid expression with a type operand.
437  SourceLocation TypeidLoc,
438  TypeSourceInfo *Operand,
439  SourceLocation RParenLoc) {
440  // C++ [expr.typeid]p4:
441  // The top-level cv-qualifiers of the lvalue expression or the type-id
442  // that is the operand of typeid are always ignored.
443  // If the type of the type-id is a class type or a reference to a class
444  // type, the class shall be completely-defined.
445  Qualifiers Quals;
446  QualType T
447  = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(),
448  Quals);
449  if (T->getAs<RecordType>() &&
450  RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
451  return ExprError();
452 
453  if (T->isVariablyModifiedType())
454  return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid) << T);
455 
456  return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), Operand,
457  SourceRange(TypeidLoc, RParenLoc));
458 }
459 
460 /// Build a C++ typeid expression with an expression operand.
462  SourceLocation TypeidLoc,
463  Expr *E,
464  SourceLocation RParenLoc) {
465  bool WasEvaluated = false;
466  if (E && !E->isTypeDependent()) {
467  if (E->getType()->isPlaceholderType()) {
468  ExprResult result = CheckPlaceholderExpr(E);
469  if (result.isInvalid()) return ExprError();
470  E = result.get();
471  }
472 
473  QualType T = E->getType();
474  if (const RecordType *RecordT = T->getAs<RecordType>()) {
475  CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl());
476  // C++ [expr.typeid]p3:
477  // [...] If the type of the expression is a class type, the class
478  // shall be completely-defined.
479  if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
480  return ExprError();
481 
482  // C++ [expr.typeid]p3:
483  // When typeid is applied to an expression other than an glvalue of a
484  // polymorphic class type [...] [the] expression is an unevaluated
485  // operand. [...]
486  if (RecordD->isPolymorphic() && E->isGLValue()) {
487  // The subexpression is potentially evaluated; switch the context
488  // and recheck the subexpression.
489  ExprResult Result = TransformToPotentiallyEvaluated(E);
490  if (Result.isInvalid()) return ExprError();
491  E = Result.get();
492 
493  // We require a vtable to query the type at run time.
494  MarkVTableUsed(TypeidLoc, RecordD);
495  WasEvaluated = true;
496  }
497  }
498 
499  // C++ [expr.typeid]p4:
500  // [...] If the type of the type-id is a reference to a possibly
501  // cv-qualified type, the result of the typeid expression refers to a
502  // std::type_info object representing the cv-unqualified referenced
503  // type.
504  Qualifiers Quals;
505  QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals);
506  if (!Context.hasSameType(T, UnqualT)) {
507  T = UnqualT;
508  E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).get();
509  }
510  }
511 
512  if (E->getType()->isVariablyModifiedType())
513  return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid)
514  << E->getType());
515  else if (!inTemplateInstantiation() &&
516  E->HasSideEffects(Context, WasEvaluated)) {
517  // The expression operand for typeid is in an unevaluated expression
518  // context, so side effects could result in unintended consequences.
519  Diag(E->getExprLoc(), WasEvaluated
520  ? diag::warn_side_effects_typeid
521  : diag::warn_side_effects_unevaluated_context);
522  }
523 
524  return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), E,
525  SourceRange(TypeidLoc, RParenLoc));
526 }
527 
528 /// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression);
531  bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
532  // typeid is not supported in OpenCL.
533  if (getLangOpts().OpenCLCPlusPlus) {
534  return ExprError(Diag(OpLoc, diag::err_openclcxx_not_supported)
535  << "typeid");
536  }
537 
538  // Find the std::type_info type.
539  if (!getStdNamespace())
540  return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
541 
542  if (!CXXTypeInfoDecl) {
543  IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info");
544  LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName);
545  LookupQualifiedName(R, getStdNamespace());
546  CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
547  // Microsoft's typeinfo doesn't have type_info in std but in the global
548  // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153.
549  if (!CXXTypeInfoDecl && LangOpts.MSVCCompat) {
550  LookupQualifiedName(R, Context.getTranslationUnitDecl());
551  CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
552  }
553  if (!CXXTypeInfoDecl)
554  return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
555  }
556 
557  if (!getLangOpts().RTTI) {
558  return ExprError(Diag(OpLoc, diag::err_no_typeid_with_fno_rtti));
559  }
560 
561  QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl);
562 
563  if (isType) {
564  // The operand is a type; handle it as such.
565  TypeSourceInfo *TInfo = nullptr;
566  QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
567  &TInfo);
568  if (T.isNull())
569  return ExprError();
570 
571  if (!TInfo)
572  TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
573 
574  return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc);
575  }
576 
577  // The operand is an expression.
578  return BuildCXXTypeId(TypeInfoType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
579 }
580 
581 /// Grabs __declspec(uuid()) off a type, or returns 0 if we cannot resolve to
582 /// a single GUID.
583 static void
586  // Optionally remove one level of pointer, reference or array indirection.
587  const Type *Ty = QT.getTypePtr();
588  if (QT->isPointerType() || QT->isReferenceType())
589  Ty = QT->getPointeeType().getTypePtr();
590  else if (QT->isArrayType())
591  Ty = Ty->getBaseElementTypeUnsafe();
592 
593  const auto *TD = Ty->getAsTagDecl();
594  if (!TD)
595  return;
596 
597  if (const auto *Uuid = TD->getMostRecentDecl()->getAttr<UuidAttr>()) {
598  UuidAttrs.insert(Uuid);
599  return;
600  }
601 
602  // __uuidof can grab UUIDs from template arguments.
603  if (const auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(TD)) {
604  const TemplateArgumentList &TAL = CTSD->getTemplateArgs();
605  for (const TemplateArgument &TA : TAL.asArray()) {
606  const UuidAttr *UuidForTA = nullptr;
607  if (TA.getKind() == TemplateArgument::Type)
608  getUuidAttrOfType(SemaRef, TA.getAsType(), UuidAttrs);
609  else if (TA.getKind() == TemplateArgument::Declaration)
610  getUuidAttrOfType(SemaRef, TA.getAsDecl()->getType(), UuidAttrs);
611 
612  if (UuidForTA)
613  UuidAttrs.insert(UuidForTA);
614  }
615  }
616 }
617 
618 /// Build a Microsoft __uuidof expression with a type operand.
620  SourceLocation TypeidLoc,
621  TypeSourceInfo *Operand,
622  SourceLocation RParenLoc) {
623  StringRef UuidStr;
624  if (!Operand->getType()->isDependentType()) {
626  getUuidAttrOfType(*this, Operand->getType(), UuidAttrs);
627  if (UuidAttrs.empty())
628  return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
629  if (UuidAttrs.size() > 1)
630  return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
631  UuidStr = UuidAttrs.back()->getGuid();
632  }
633 
634  return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), Operand, UuidStr,
635  SourceRange(TypeidLoc, RParenLoc));
636 }
637 
638 /// Build a Microsoft __uuidof expression with an expression operand.
640  SourceLocation TypeidLoc,
641  Expr *E,
642  SourceLocation RParenLoc) {
643  StringRef UuidStr;
644  if (!E->getType()->isDependentType()) {
646  UuidStr = "00000000-0000-0000-0000-000000000000";
647  } else {
649  getUuidAttrOfType(*this, E->getType(), UuidAttrs);
650  if (UuidAttrs.empty())
651  return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
652  if (UuidAttrs.size() > 1)
653  return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
654  UuidStr = UuidAttrs.back()->getGuid();
655  }
656  }
657 
658  return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), E, UuidStr,
659  SourceRange(TypeidLoc, RParenLoc));
660 }
661 
662 /// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression);
665  bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
666  // If MSVCGuidDecl has not been cached, do the lookup.
667  if (!MSVCGuidDecl) {
668  IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID");
669  LookupResult R(*this, GuidII, SourceLocation(), LookupTagName);
670  LookupQualifiedName(R, Context.getTranslationUnitDecl());
671  MSVCGuidDecl = R.getAsSingle<RecordDecl>();
672  if (!MSVCGuidDecl)
673  return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof));
674  }
675 
676  QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl);
677 
678  if (isType) {
679  // The operand is a type; handle it as such.
680  TypeSourceInfo *TInfo = nullptr;
681  QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
682  &TInfo);
683  if (T.isNull())
684  return ExprError();
685 
686  if (!TInfo)
687  TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
688 
689  return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc);
690  }
691 
692  // The operand is an expression.
693  return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
694 }
695 
696 /// ActOnCXXBoolLiteral - Parse {true,false} literals.
699  assert((Kind == tok::kw_true || Kind == tok::kw_false) &&
700  "Unknown C++ Boolean value!");
701  return new (Context)
702  CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc);
703 }
704 
705 /// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
708  return new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
709 }
710 
711 /// ActOnCXXThrow - Parse throw expressions.
714  bool IsThrownVarInScope = false;
715  if (Ex) {
716  // C++0x [class.copymove]p31:
717  // When certain criteria are met, an implementation is allowed to omit the
718  // copy/move construction of a class object [...]
719  //
720  // - in a throw-expression, when the operand is the name of a
721  // non-volatile automatic object (other than a function or catch-
722  // clause parameter) whose scope does not extend beyond the end of the
723  // innermost enclosing try-block (if there is one), the copy/move
724  // operation from the operand to the exception object (15.1) can be
725  // omitted by constructing the automatic object directly into the
726  // exception object
727  if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens()))
728  if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
729  if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) {
730  for( ; S; S = S->getParent()) {
731  if (S->isDeclScope(Var)) {
732  IsThrownVarInScope = true;
733  break;
734  }
735 
736  if (S->getFlags() &
740  break;
741  }
742  }
743  }
744  }
745 
746  return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope);
747 }
748 
750  bool IsThrownVarInScope) {
751  // Don't report an error if 'throw' is used in system headers.
752  if (!getLangOpts().CXXExceptions &&
753  !getSourceManager().isInSystemHeader(OpLoc) && !getLangOpts().CUDA) {
754  // Delay error emission for the OpenMP device code.
755  targetDiag(OpLoc, diag::err_exceptions_disabled) << "throw";
756  }
757 
758  // Exceptions aren't allowed in CUDA device code.
759  if (getLangOpts().CUDA)
760  CUDADiagIfDeviceCode(OpLoc, diag::err_cuda_device_exceptions)
761  << "throw" << CurrentCUDATarget();
762 
763  if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
764  Diag(OpLoc, diag::err_omp_simd_region_cannot_use_stmt) << "throw";
765 
766  if (Ex && !Ex->isTypeDependent()) {
767  QualType ExceptionObjectTy = Context.getExceptionObjectType(Ex->getType());
768  if (CheckCXXThrowOperand(OpLoc, ExceptionObjectTy, Ex))
769  return ExprError();
770 
771  // Initialize the exception result. This implicitly weeds out
772  // abstract types or types with inaccessible copy constructors.
773 
774  // C++0x [class.copymove]p31:
775  // When certain criteria are met, an implementation is allowed to omit the
776  // copy/move construction of a class object [...]
777  //
778  // - in a throw-expression, when the operand is the name of a
779  // non-volatile automatic object (other than a function or
780  // catch-clause
781  // parameter) whose scope does not extend beyond the end of the
782  // innermost enclosing try-block (if there is one), the copy/move
783  // operation from the operand to the exception object (15.1) can be
784  // omitted by constructing the automatic object directly into the
785  // exception object
786  const VarDecl *NRVOVariable = nullptr;
787  if (IsThrownVarInScope)
788  NRVOVariable = getCopyElisionCandidate(QualType(), Ex, CES_Strict);
789 
791  OpLoc, ExceptionObjectTy,
792  /*NRVO=*/NRVOVariable != nullptr);
793  ExprResult Res = PerformMoveOrCopyInitialization(
794  Entity, NRVOVariable, QualType(), Ex, IsThrownVarInScope);
795  if (Res.isInvalid())
796  return ExprError();
797  Ex = Res.get();
798  }
799 
800  return new (Context)
801  CXXThrowExpr(Ex, Context.VoidTy, OpLoc, IsThrownVarInScope);
802 }
803 
804 static void
806  llvm::DenseMap<CXXRecordDecl *, unsigned> &SubobjectsSeen,
807  llvm::SmallPtrSetImpl<CXXRecordDecl *> &VBases,
808  llvm::SetVector<CXXRecordDecl *> &PublicSubobjectsSeen,
809  bool ParentIsPublic) {
810  for (const CXXBaseSpecifier &BS : RD->bases()) {
811  CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
812  bool NewSubobject;
813  // Virtual bases constitute the same subobject. Non-virtual bases are
814  // always distinct subobjects.
815  if (BS.isVirtual())
816  NewSubobject = VBases.insert(BaseDecl).second;
817  else
818  NewSubobject = true;
819 
820  if (NewSubobject)
821  ++SubobjectsSeen[BaseDecl];
822 
823  // Only add subobjects which have public access throughout the entire chain.
824  bool PublicPath = ParentIsPublic && BS.getAccessSpecifier() == AS_public;
825  if (PublicPath)
826  PublicSubobjectsSeen.insert(BaseDecl);
827 
828  // Recurse on to each base subobject.
829  collectPublicBases(BaseDecl, SubobjectsSeen, VBases, PublicSubobjectsSeen,
830  PublicPath);
831  }
832 }
833 
836  llvm::DenseMap<CXXRecordDecl *, unsigned> SubobjectsSeen;
837  llvm::SmallSet<CXXRecordDecl *, 2> VBases;
838  llvm::SetVector<CXXRecordDecl *> PublicSubobjectsSeen;
839  SubobjectsSeen[RD] = 1;
840  PublicSubobjectsSeen.insert(RD);
841  collectPublicBases(RD, SubobjectsSeen, VBases, PublicSubobjectsSeen,
842  /*ParentIsPublic=*/true);
843 
844  for (CXXRecordDecl *PublicSubobject : PublicSubobjectsSeen) {
845  // Skip ambiguous objects.
846  if (SubobjectsSeen[PublicSubobject] > 1)
847  continue;
848 
849  Objects.push_back(PublicSubobject);
850  }
851 }
852 
853 /// CheckCXXThrowOperand - Validate the operand of a throw.
855  QualType ExceptionObjectTy, Expr *E) {
856  // If the type of the exception would be an incomplete type or a pointer
857  // to an incomplete type other than (cv) void the program is ill-formed.
858  QualType Ty = ExceptionObjectTy;
859  bool isPointer = false;
860  if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
861  Ty = Ptr->getPointeeType();
862  isPointer = true;
863  }
864  if (!isPointer || !Ty->isVoidType()) {
865  if (RequireCompleteType(ThrowLoc, Ty,
866  isPointer ? diag::err_throw_incomplete_ptr
867  : diag::err_throw_incomplete,
868  E->getSourceRange()))
869  return true;
870 
871  if (RequireNonAbstractType(ThrowLoc, ExceptionObjectTy,
872  diag::err_throw_abstract_type, E))
873  return true;
874  }
875 
876  // If the exception has class type, we need additional handling.
877  CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
878  if (!RD)
879  return false;
880 
881  // If we are throwing a polymorphic class type or pointer thereof,
882  // exception handling will make use of the vtable.
883  MarkVTableUsed(ThrowLoc, RD);
884 
885  // If a pointer is thrown, the referenced object will not be destroyed.
886  if (isPointer)
887  return false;
888 
889  // If the class has a destructor, we must be able to call it.
890  if (!RD->hasIrrelevantDestructor()) {
891  if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
892  MarkFunctionReferenced(E->getExprLoc(), Destructor);
893  CheckDestructorAccess(E->getExprLoc(), Destructor,
894  PDiag(diag::err_access_dtor_exception) << Ty);
895  if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
896  return true;
897  }
898  }
899 
900  // The MSVC ABI creates a list of all types which can catch the exception
901  // object. This list also references the appropriate copy constructor to call
902  // if the object is caught by value and has a non-trivial copy constructor.
903  if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
904  // We are only interested in the public, unambiguous bases contained within
905  // the exception object. Bases which are ambiguous or otherwise
906  // inaccessible are not catchable types.
907  llvm::SmallVector<CXXRecordDecl *, 2> UnambiguousPublicSubobjects;
908  getUnambiguousPublicSubobjects(RD, UnambiguousPublicSubobjects);
909 
910  for (CXXRecordDecl *Subobject : UnambiguousPublicSubobjects) {
911  // Attempt to lookup the copy constructor. Various pieces of machinery
912  // will spring into action, like template instantiation, which means this
913  // cannot be a simple walk of the class's decls. Instead, we must perform
914  // lookup and overload resolution.
915  CXXConstructorDecl *CD = LookupCopyingConstructor(Subobject, 0);
916  if (!CD)
917  continue;
918 
919  // Mark the constructor referenced as it is used by this throw expression.
920  MarkFunctionReferenced(E->getExprLoc(), CD);
921 
922  // Skip this copy constructor if it is trivial, we don't need to record it
923  // in the catchable type data.
924  if (CD->isTrivial())
925  continue;
926 
927  // The copy constructor is non-trivial, create a mapping from this class
928  // type to this constructor.
929  // N.B. The selection of copy constructor is not sensitive to this
930  // particular throw-site. Lookup will be performed at the catch-site to
931  // ensure that the copy constructor is, in fact, accessible (via
932  // friendship or any other means).
933  Context.addCopyConstructorForExceptionObject(Subobject, CD);
934 
935  // We don't keep the instantiated default argument expressions around so
936  // we must rebuild them here.
937  for (unsigned I = 1, E = CD->getNumParams(); I != E; ++I) {
938  if (CheckCXXDefaultArgExpr(ThrowLoc, CD, CD->getParamDecl(I)))
939  return true;
940  }
941  }
942  }
943 
944  // Under the Itanium C++ ABI, memory for the exception object is allocated by
945  // the runtime with no ability for the compiler to request additional
946  // alignment. Warn if the exception type requires alignment beyond the minimum
947  // guaranteed by the target C++ runtime.
948  if (Context.getTargetInfo().getCXXABI().isItaniumFamily()) {
949  CharUnits TypeAlign = Context.getTypeAlignInChars(Ty);
950  CharUnits ExnObjAlign = Context.getExnObjectAlignment();
951  if (ExnObjAlign < TypeAlign) {
952  Diag(ThrowLoc, diag::warn_throw_underaligned_obj);
953  Diag(ThrowLoc, diag::note_throw_underaligned_obj)
954  << Ty << (unsigned)TypeAlign.getQuantity()
955  << (unsigned)ExnObjAlign.getQuantity();
956  }
957  }
958 
959  return false;
960 }
961 
963  ArrayRef<FunctionScopeInfo *> FunctionScopes, QualType ThisTy,
964  DeclContext *CurSemaContext, ASTContext &ASTCtx) {
965 
966  QualType ClassType = ThisTy->getPointeeType();
967  LambdaScopeInfo *CurLSI = nullptr;
968  DeclContext *CurDC = CurSemaContext;
969 
970  // Iterate through the stack of lambdas starting from the innermost lambda to
971  // the outermost lambda, checking if '*this' is ever captured by copy - since
972  // that could change the cv-qualifiers of the '*this' object.
973  // The object referred to by '*this' starts out with the cv-qualifiers of its
974  // member function. We then start with the innermost lambda and iterate
975  // outward checking to see if any lambda performs a by-copy capture of '*this'
976  // - and if so, any nested lambda must respect the 'constness' of that
977  // capturing lamdbda's call operator.
978  //
979 
980  // Since the FunctionScopeInfo stack is representative of the lexical
981  // nesting of the lambda expressions during initial parsing (and is the best
982  // place for querying information about captures about lambdas that are
983  // partially processed) and perhaps during instantiation of function templates
984  // that contain lambda expressions that need to be transformed BUT not
985  // necessarily during instantiation of a nested generic lambda's function call
986  // operator (which might even be instantiated at the end of the TU) - at which
987  // time the DeclContext tree is mature enough to query capture information
988  // reliably - we use a two pronged approach to walk through all the lexically
989  // enclosing lambda expressions:
990  //
991  // 1) Climb down the FunctionScopeInfo stack as long as each item represents
992  // a Lambda (i.e. LambdaScopeInfo) AND each LSI's 'closure-type' is lexically
993  // enclosed by the call-operator of the LSI below it on the stack (while
994  // tracking the enclosing DC for step 2 if needed). Note the topmost LSI on
995  // the stack represents the innermost lambda.
996  //
997  // 2) If we run out of enclosing LSI's, check if the enclosing DeclContext
998  // represents a lambda's call operator. If it does, we must be instantiating
999  // a generic lambda's call operator (represented by the Current LSI, and
1000  // should be the only scenario where an inconsistency between the LSI and the
1001  // DeclContext should occur), so climb out the DeclContexts if they
1002  // represent lambdas, while querying the corresponding closure types
1003  // regarding capture information.
1004 
1005  // 1) Climb down the function scope info stack.
1006  for (int I = FunctionScopes.size();
1007  I-- && isa<LambdaScopeInfo>(FunctionScopes[I]) &&
1008  (!CurLSI || !CurLSI->Lambda || CurLSI->Lambda->getDeclContext() ==
1009  cast<LambdaScopeInfo>(FunctionScopes[I])->CallOperator);
1010  CurDC = getLambdaAwareParentOfDeclContext(CurDC)) {
1011  CurLSI = cast<LambdaScopeInfo>(FunctionScopes[I]);
1012 
1013  if (!CurLSI->isCXXThisCaptured())
1014  continue;
1015 
1016  auto C = CurLSI->getCXXThisCapture();
1017 
1018  if (C.isCopyCapture()) {
1020  if (CurLSI->CallOperator->isConst())
1021  ClassType.addConst();
1022  return ASTCtx.getPointerType(ClassType);
1023  }
1024  }
1025 
1026  // 2) We've run out of ScopeInfos but check if CurDC is a lambda (which can
1027  // happen during instantiation of its nested generic lambda call operator)
1028  if (isLambdaCallOperator(CurDC)) {
1029  assert(CurLSI && "While computing 'this' capture-type for a generic "
1030  "lambda, we must have a corresponding LambdaScopeInfo");
1032  "While computing 'this' capture-type for a generic lambda, when we "
1033  "run out of enclosing LSI's, yet the enclosing DC is a "
1034  "lambda-call-operator we must be (i.e. Current LSI) in a generic "
1035  "lambda call oeprator");
1036  assert(CurDC == getLambdaAwareParentOfDeclContext(CurLSI->CallOperator));
1037 
1038  auto IsThisCaptured =
1039  [](CXXRecordDecl *Closure, bool &IsByCopy, bool &IsConst) {
1040  IsConst = false;
1041  IsByCopy = false;
1042  for (auto &&C : Closure->captures()) {
1043  if (C.capturesThis()) {
1044  if (C.getCaptureKind() == LCK_StarThis)
1045  IsByCopy = true;
1046  if (Closure->getLambdaCallOperator()->isConst())
1047  IsConst = true;
1048  return true;
1049  }
1050  }
1051  return false;
1052  };
1053 
1054  bool IsByCopyCapture = false;
1055  bool IsConstCapture = false;
1056  CXXRecordDecl *Closure = cast<CXXRecordDecl>(CurDC->getParent());
1057  while (Closure &&
1058  IsThisCaptured(Closure, IsByCopyCapture, IsConstCapture)) {
1059  if (IsByCopyCapture) {
1061  if (IsConstCapture)
1062  ClassType.addConst();
1063  return ASTCtx.getPointerType(ClassType);
1064  }
1065  Closure = isLambdaCallOperator(Closure->getParent())
1066  ? cast<CXXRecordDecl>(Closure->getParent()->getParent())
1067  : nullptr;
1068  }
1069  }
1070  return ASTCtx.getPointerType(ClassType);
1071 }
1072 
1074  DeclContext *DC = getFunctionLevelDeclContext();
1075  QualType ThisTy = CXXThisTypeOverride;
1076 
1077  if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) {
1078  if (method && method->isInstance())
1079  ThisTy = method->getThisType();
1080  }
1081 
1082  if (ThisTy.isNull() && isLambdaCallOperator(CurContext) &&
1083  inTemplateInstantiation()) {
1084 
1085  assert(isa<CXXRecordDecl>(DC) &&
1086  "Trying to get 'this' type from static method?");
1087 
1088  // This is a lambda call operator that is being instantiated as a default
1089  // initializer. DC must point to the enclosing class type, so we can recover
1090  // the 'this' type from it.
1091 
1092  QualType ClassTy = Context.getTypeDeclType(cast<CXXRecordDecl>(DC));
1093  // There are no cv-qualifiers for 'this' within default initializers,
1094  // per [expr.prim.general]p4.
1095  ThisTy = Context.getPointerType(ClassTy);
1096  }
1097 
1098  // If we are within a lambda's call operator, the cv-qualifiers of 'this'
1099  // might need to be adjusted if the lambda or any of its enclosing lambda's
1100  // captures '*this' by copy.
1101  if (!ThisTy.isNull() && isLambdaCallOperator(CurContext))
1102  return adjustCVQualifiersForCXXThisWithinLambda(FunctionScopes, ThisTy,
1103  CurContext, Context);
1104  return ThisTy;
1105 }
1106 
1108  Decl *ContextDecl,
1109  Qualifiers CXXThisTypeQuals,
1110  bool Enabled)
1111  : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false)
1112 {
1113  if (!Enabled || !ContextDecl)
1114  return;
1115 
1116  CXXRecordDecl *Record = nullptr;
1117  if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl))
1118  Record = Template->getTemplatedDecl();
1119  else
1120  Record = cast<CXXRecordDecl>(ContextDecl);
1121 
1122  QualType T = S.Context.getRecordType(Record);
1123  T = S.getASTContext().getQualifiedType(T, CXXThisTypeQuals);
1124 
1126 
1127  this->Enabled = true;
1128 }
1129 
1130 
1132  if (Enabled) {
1133  S.CXXThisTypeOverride = OldCXXThisTypeOverride;
1134  }
1135 }
1136 
1137 bool Sema::CheckCXXThisCapture(SourceLocation Loc, const bool Explicit,
1138  bool BuildAndDiagnose, const unsigned *const FunctionScopeIndexToStopAt,
1139  const bool ByCopy) {
1140  // We don't need to capture this in an unevaluated context.
1141  if (isUnevaluatedContext() && !Explicit)
1142  return true;
1143 
1144  assert((!ByCopy || Explicit) && "cannot implicitly capture *this by value");
1145 
1146  const int MaxFunctionScopesIndex = FunctionScopeIndexToStopAt
1147  ? *FunctionScopeIndexToStopAt
1148  : FunctionScopes.size() - 1;
1149 
1150  // Check that we can capture the *enclosing object* (referred to by '*this')
1151  // by the capturing-entity/closure (lambda/block/etc) at
1152  // MaxFunctionScopesIndex-deep on the FunctionScopes stack.
1153 
1154  // Note: The *enclosing object* can only be captured by-value by a
1155  // closure that is a lambda, using the explicit notation:
1156  // [*this] { ... }.
1157  // Every other capture of the *enclosing object* results in its by-reference
1158  // capture.
1159 
1160  // For a closure 'L' (at MaxFunctionScopesIndex in the FunctionScopes
1161  // stack), we can capture the *enclosing object* only if:
1162  // - 'L' has an explicit byref or byval capture of the *enclosing object*
1163  // - or, 'L' has an implicit capture.
1164  // AND
1165  // -- there is no enclosing closure
1166  // -- or, there is some enclosing closure 'E' that has already captured the
1167  // *enclosing object*, and every intervening closure (if any) between 'E'
1168  // and 'L' can implicitly capture the *enclosing object*.
1169  // -- or, every enclosing closure can implicitly capture the
1170  // *enclosing object*
1171 
1172 
1173  unsigned NumCapturingClosures = 0;
1174  for (int idx = MaxFunctionScopesIndex; idx >= 0; idx--) {
1175  if (CapturingScopeInfo *CSI =
1176  dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) {
1177  if (CSI->CXXThisCaptureIndex != 0) {
1178  // 'this' is already being captured; there isn't anything more to do.
1179  CSI->Captures[CSI->CXXThisCaptureIndex - 1].markUsed(BuildAndDiagnose);
1180  break;
1181  }
1182  LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI);
1184  // This context can't implicitly capture 'this'; fail out.
1185  if (BuildAndDiagnose)
1186  Diag(Loc, diag::err_this_capture)
1187  << (Explicit && idx == MaxFunctionScopesIndex);
1188  return true;
1189  }
1190  if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref ||
1191  CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval ||
1192  CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block ||
1193  CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_CapturedRegion ||
1194  (Explicit && idx == MaxFunctionScopesIndex)) {
1195  // Regarding (Explicit && idx == MaxFunctionScopesIndex): only the first
1196  // iteration through can be an explicit capture, all enclosing closures,
1197  // if any, must perform implicit captures.
1198 
1199  // This closure can capture 'this'; continue looking upwards.
1200  NumCapturingClosures++;
1201  continue;
1202  }
1203  // This context can't implicitly capture 'this'; fail out.
1204  if (BuildAndDiagnose)
1205  Diag(Loc, diag::err_this_capture)
1206  << (Explicit && idx == MaxFunctionScopesIndex);
1207  return true;
1208  }
1209  break;
1210  }
1211  if (!BuildAndDiagnose) return false;
1212 
1213  // If we got here, then the closure at MaxFunctionScopesIndex on the
1214  // FunctionScopes stack, can capture the *enclosing object*, so capture it
1215  // (including implicit by-reference captures in any enclosing closures).
1216 
1217  // In the loop below, respect the ByCopy flag only for the closure requesting
1218  // the capture (i.e. first iteration through the loop below). Ignore it for
1219  // all enclosing closure's up to NumCapturingClosures (since they must be
1220  // implicitly capturing the *enclosing object* by reference (see loop
1221  // above)).
1222  assert((!ByCopy ||
1223  dyn_cast<LambdaScopeInfo>(FunctionScopes[MaxFunctionScopesIndex])) &&
1224  "Only a lambda can capture the enclosing object (referred to by "
1225  "*this) by copy");
1226  QualType ThisTy = getCurrentThisType();
1227  for (int idx = MaxFunctionScopesIndex; NumCapturingClosures;
1228  --idx, --NumCapturingClosures) {
1229  CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]);
1230 
1231  // The type of the corresponding data member (not a 'this' pointer if 'by
1232  // copy').
1233  QualType CaptureType = ThisTy;
1234  if (ByCopy) {
1235  // If we are capturing the object referred to by '*this' by copy, ignore
1236  // any cv qualifiers inherited from the type of the member function for
1237  // the type of the closure-type's corresponding data member and any use
1238  // of 'this'.
1239  CaptureType = ThisTy->getPointeeType();
1241  }
1242 
1243  bool isNested = NumCapturingClosures > 1;
1244  CSI->addThisCapture(isNested, Loc, CaptureType, ByCopy);
1245  }
1246  return false;
1247 }
1248 
1250  /// C++ 9.3.2: In the body of a non-static member function, the keyword this
1251  /// is a non-lvalue expression whose value is the address of the object for
1252  /// which the function is called.
1253 
1254  QualType ThisTy = getCurrentThisType();
1255  if (ThisTy.isNull())
1256  return Diag(Loc, diag::err_invalid_this_use);
1257  return BuildCXXThisExpr(Loc, ThisTy, /*IsImplicit=*/false);
1258 }
1259 
1261  bool IsImplicit) {
1262  auto *This = new (Context) CXXThisExpr(Loc, Type, IsImplicit);
1264  return This;
1265 }
1266 
1269 }
1270 
1272  // If we're outside the body of a member function, then we'll have a specified
1273  // type for 'this'.
1275  return false;
1276 
1277  // Determine whether we're looking into a class that's currently being
1278  // defined.
1279  CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl();
1280  return Class && Class->isBeingDefined();
1281 }
1282 
1283 /// Parse construction of a specified type.
1284 /// Can be interpreted either as function-style casting ("int(x)")
1285 /// or class type construction ("ClassType(x,y,z)")
1286 /// or creation of a value-initialized type ("int()").
1287 ExprResult
1289  SourceLocation LParenOrBraceLoc,
1290  MultiExprArg exprs,
1291  SourceLocation RParenOrBraceLoc,
1292  bool ListInitialization) {
1293  if (!TypeRep)
1294  return ExprError();
1295 
1296  TypeSourceInfo *TInfo;
1297  QualType Ty = GetTypeFromParser(TypeRep, &TInfo);
1298  if (!TInfo)
1300 
1301  auto Result = BuildCXXTypeConstructExpr(TInfo, LParenOrBraceLoc, exprs,
1302  RParenOrBraceLoc, ListInitialization);
1303  // Avoid creating a non-type-dependent expression that contains typos.
1304  // Non-type-dependent expressions are liable to be discarded without
1305  // checking for embedded typos.
1306  if (!Result.isInvalid() && Result.get()->isInstantiationDependent() &&
1307  !Result.get()->isTypeDependent())
1309  return Result;
1310 }
1311 
1312 ExprResult
1314  SourceLocation LParenOrBraceLoc,
1315  MultiExprArg Exprs,
1316  SourceLocation RParenOrBraceLoc,
1317  bool ListInitialization) {
1318  QualType Ty = TInfo->getType();
1319  SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc();
1320 
1322  // FIXME: CXXUnresolvedConstructExpr does not model list-initialization
1323  // directly. We work around this by dropping the locations of the braces.
1324  SourceRange Locs = ListInitialization
1325  ? SourceRange()
1326  : SourceRange(LParenOrBraceLoc, RParenOrBraceLoc);
1327  return CXXUnresolvedConstructExpr::Create(Context, TInfo, Locs.getBegin(),
1328  Exprs, Locs.getEnd());
1329  }
1330 
1331  assert((!ListInitialization ||
1332  (Exprs.size() == 1 && isa<InitListExpr>(Exprs[0]))) &&
1333  "List initialization must have initializer list as expression.");
1334  SourceRange FullRange = SourceRange(TyBeginLoc, RParenOrBraceLoc);
1335 
1338  Exprs.size()
1339  ? ListInitialization
1341  TyBeginLoc, LParenOrBraceLoc, RParenOrBraceLoc)
1342  : InitializationKind::CreateDirect(TyBeginLoc, LParenOrBraceLoc,
1343  RParenOrBraceLoc)
1344  : InitializationKind::CreateValue(TyBeginLoc, LParenOrBraceLoc,
1345  RParenOrBraceLoc);
1346 
1347  // C++1z [expr.type.conv]p1:
1348  // If the type is a placeholder for a deduced class type, [...perform class
1349  // template argument deduction...]
1350  DeducedType *Deduced = Ty->getContainedDeducedType();
1351  if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
1353  Kind, Exprs);
1354  if (Ty.isNull())
1355  return ExprError();
1356  Entity = InitializedEntity::InitializeTemporary(TInfo, Ty);
1357  }
1358 
1359  // C++ [expr.type.conv]p1:
1360  // If the expression list is a parenthesized single expression, the type
1361  // conversion expression is equivalent (in definedness, and if defined in
1362  // meaning) to the corresponding cast expression.
1363  if (Exprs.size() == 1 && !ListInitialization &&
1364  !isa<InitListExpr>(Exprs[0])) {
1365  Expr *Arg = Exprs[0];
1366  return BuildCXXFunctionalCastExpr(TInfo, Ty, LParenOrBraceLoc, Arg,
1367  RParenOrBraceLoc);
1368  }
1369 
1370  // For an expression of the form T(), T shall not be an array type.
1371  QualType ElemTy = Ty;
1372  if (Ty->isArrayType()) {
1373  if (!ListInitialization)
1374  return ExprError(Diag(TyBeginLoc, diag::err_value_init_for_array_type)
1375  << FullRange);
1376  ElemTy = Context.getBaseElementType(Ty);
1377  }
1378 
1379  // There doesn't seem to be an explicit rule against this but sanity demands
1380  // we only construct objects with object types.
1381  if (Ty->isFunctionType())
1382  return ExprError(Diag(TyBeginLoc, diag::err_init_for_function_type)
1383  << Ty << FullRange);
1384 
1385  // C++17 [expr.type.conv]p2:
1386  // If the type is cv void and the initializer is (), the expression is a
1387  // prvalue of the specified type that performs no initialization.
1388  if (!Ty->isVoidType() &&
1389  RequireCompleteType(TyBeginLoc, ElemTy,
1390  diag::err_invalid_incomplete_type_use, FullRange))
1391  return ExprError();
1392 
1393  // Otherwise, the expression is a prvalue of the specified type whose
1394  // result object is direct-initialized (11.6) with the initializer.
1395  InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
1396  ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Exprs);
1397 
1398  if (Result.isInvalid())
1399  return Result;
1400 
1401  Expr *Inner = Result.get();
1402  if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Inner))
1403  Inner = BTE->getSubExpr();
1404  if (!isa<CXXTemporaryObjectExpr>(Inner) &&
1405  !isa<CXXScalarValueInitExpr>(Inner)) {
1406  // If we created a CXXTemporaryObjectExpr, that node also represents the
1407  // functional cast. Otherwise, create an explicit cast to represent
1408  // the syntactic form of a functional-style cast that was used here.
1409  //
1410  // FIXME: Creating a CXXFunctionalCastExpr around a CXXConstructExpr
1411  // would give a more consistent AST representation than using a
1412  // CXXTemporaryObjectExpr. It's also weird that the functional cast
1413  // is sometimes handled by initialization and sometimes not.
1414  QualType ResultType = Result.get()->getType();
1415  SourceRange Locs = ListInitialization
1416  ? SourceRange()
1417  : SourceRange(LParenOrBraceLoc, RParenOrBraceLoc);
1419  Context, ResultType, Expr::getValueKindForType(Ty), TInfo, CK_NoOp,
1420  Result.get(), /*Path=*/nullptr, Locs.getBegin(), Locs.getEnd());
1421  }
1422 
1423  return Result;
1424 }
1425 
1427  // [CUDA] Ignore this function, if we can't call it.
1428  const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext);
1429  if (getLangOpts().CUDA &&
1430  IdentifyCUDAPreference(Caller, Method) <= CFP_WrongSide)
1431  return false;
1432 
1434  bool Result = Method->isUsualDeallocationFunction(PreventedBy);
1435 
1436  if (Result || !getLangOpts().CUDA || PreventedBy.empty())
1437  return Result;
1438 
1439  // In case of CUDA, return true if none of the 1-argument deallocator
1440  // functions are actually callable.
1441  return llvm::none_of(PreventedBy, [&](const FunctionDecl *FD) {
1442  assert(FD->getNumParams() == 1 &&
1443  "Only single-operand functions should be in PreventedBy");
1444  return IdentifyCUDAPreference(Caller, FD) >= CFP_HostDevice;
1445  });
1446 }
1447 
1448 /// Determine whether the given function is a non-placement
1449 /// deallocation function.
1451  if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD))
1452  return S.isUsualDeallocationFunction(Method);
1453 
1454  if (FD->getOverloadedOperator() != OO_Delete &&
1455  FD->getOverloadedOperator() != OO_Array_Delete)
1456  return false;
1457 
1458  unsigned UsualParams = 1;
1459 
1460  if (S.getLangOpts().SizedDeallocation && UsualParams < FD->getNumParams() &&
1462  FD->getParamDecl(UsualParams)->getType(),
1463  S.Context.getSizeType()))
1464  ++UsualParams;
1465 
1466  if (S.getLangOpts().AlignedAllocation && UsualParams < FD->getNumParams() &&
1468  FD->getParamDecl(UsualParams)->getType(),
1470  ++UsualParams;
1471 
1472  return UsualParams == FD->getNumParams();
1473 }
1474 
1475 namespace {
1476  struct UsualDeallocFnInfo {
1477  UsualDeallocFnInfo() : Found(), FD(nullptr) {}
1478  UsualDeallocFnInfo(Sema &S, DeclAccessPair Found)
1479  : Found(Found), FD(dyn_cast<FunctionDecl>(Found->getUnderlyingDecl())),
1480  Destroying(false), HasSizeT(false), HasAlignValT(false),
1481  CUDAPref(Sema::CFP_Native) {
1482  // A function template declaration is never a usual deallocation function.
1483  if (!FD)
1484  return;
1485  unsigned NumBaseParams = 1;
1486  if (FD->isDestroyingOperatorDelete()) {
1487  Destroying = true;
1488  ++NumBaseParams;
1489  }
1490 
1491  if (NumBaseParams < FD->getNumParams() &&
1493  FD->getParamDecl(NumBaseParams)->getType(),
1494  S.Context.getSizeType())) {
1495  ++NumBaseParams;
1496  HasSizeT = true;
1497  }
1498 
1499  if (NumBaseParams < FD->getNumParams() &&
1500  FD->getParamDecl(NumBaseParams)->getType()->isAlignValT()) {
1501  ++NumBaseParams;
1502  HasAlignValT = true;
1503  }
1504 
1505  // In CUDA, determine how much we'd like / dislike to call this.
1506  if (S.getLangOpts().CUDA)
1507  if (auto *Caller = dyn_cast<FunctionDecl>(S.CurContext))
1508  CUDAPref = S.IdentifyCUDAPreference(Caller, FD);
1509  }
1510 
1511  explicit operator bool() const { return FD; }
1512 
1513  bool isBetterThan(const UsualDeallocFnInfo &Other, bool WantSize,
1514  bool WantAlign) const {
1515  // C++ P0722:
1516  // A destroying operator delete is preferred over a non-destroying
1517  // operator delete.
1518  if (Destroying != Other.Destroying)
1519  return Destroying;
1520 
1521  // C++17 [expr.delete]p10:
1522  // If the type has new-extended alignment, a function with a parameter
1523  // of type std::align_val_t is preferred; otherwise a function without
1524  // such a parameter is preferred
1525  if (HasAlignValT != Other.HasAlignValT)
1526  return HasAlignValT == WantAlign;
1527 
1528  if (HasSizeT != Other.HasSizeT)
1529  return HasSizeT == WantSize;
1530 
1531  // Use CUDA call preference as a tiebreaker.
1532  return CUDAPref > Other.CUDAPref;
1533  }
1534 
1535  DeclAccessPair Found;
1536  FunctionDecl *FD;
1537  bool Destroying, HasSizeT, HasAlignValT;
1539  };
1540 }
1541 
1542 /// Determine whether a type has new-extended alignment. This may be called when
1543 /// the type is incomplete (for a delete-expression with an incomplete pointee
1544 /// type), in which case it will conservatively return false if the alignment is
1545 /// not known.
1546 static bool hasNewExtendedAlignment(Sema &S, QualType AllocType) {
1547  return S.getLangOpts().AlignedAllocation &&
1548  S.getASTContext().getTypeAlignIfKnown(AllocType) >
1550 }
1551 
1552 /// Select the correct "usual" deallocation function to use from a selection of
1553 /// deallocation functions (either global or class-scope).
1554 static UsualDeallocFnInfo resolveDeallocationOverload(
1555  Sema &S, LookupResult &R, bool WantSize, bool WantAlign,
1556  llvm::SmallVectorImpl<UsualDeallocFnInfo> *BestFns = nullptr) {
1557  UsualDeallocFnInfo Best;
1558 
1559  for (auto I = R.begin(), E = R.end(); I != E; ++I) {
1560  UsualDeallocFnInfo Info(S, I.getPair());
1561  if (!Info || !isNonPlacementDeallocationFunction(S, Info.FD) ||
1562  Info.CUDAPref == Sema::CFP_Never)
1563  continue;
1564 
1565  if (!Best) {
1566  Best = Info;
1567  if (BestFns)
1568  BestFns->push_back(Info);
1569  continue;
1570  }
1571 
1572  if (Best.isBetterThan(Info, WantSize, WantAlign))
1573  continue;
1574 
1575  // If more than one preferred function is found, all non-preferred
1576  // functions are eliminated from further consideration.
1577  if (BestFns && Info.isBetterThan(Best, WantSize, WantAlign))
1578  BestFns->clear();
1579 
1580  Best = Info;
1581  if (BestFns)
1582  BestFns->push_back(Info);
1583  }
1584 
1585  return Best;
1586 }
1587 
1588 /// Determine whether a given type is a class for which 'delete[]' would call
1589 /// a member 'operator delete[]' with a 'size_t' parameter. This implies that
1590 /// we need to store the array size (even if the type is
1591 /// trivially-destructible).
1593  QualType allocType) {
1594  const RecordType *record =
1595  allocType->getBaseElementTypeUnsafe()->getAs<RecordType>();
1596  if (!record) return false;
1597 
1598  // Try to find an operator delete[] in class scope.
1599 
1600  DeclarationName deleteName =
1601  S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete);
1602  LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName);
1603  S.LookupQualifiedName(ops, record->getDecl());
1604 
1605  // We're just doing this for information.
1606  ops.suppressDiagnostics();
1607 
1608  // Very likely: there's no operator delete[].
1609  if (ops.empty()) return false;
1610 
1611  // If it's ambiguous, it should be illegal to call operator delete[]
1612  // on this thing, so it doesn't matter if we allocate extra space or not.
1613  if (ops.isAmbiguous()) return false;
1614 
1615  // C++17 [expr.delete]p10:
1616  // If the deallocation functions have class scope, the one without a
1617  // parameter of type std::size_t is selected.
1618  auto Best = resolveDeallocationOverload(
1619  S, ops, /*WantSize*/false,
1620  /*WantAlign*/hasNewExtendedAlignment(S, allocType));
1621  return Best && Best.HasSizeT;
1622 }
1623 
1624 /// Parsed a C++ 'new' expression (C++ 5.3.4).
1625 ///
1626 /// E.g.:
1627 /// @code new (memory) int[size][4] @endcode
1628 /// or
1629 /// @code ::new Foo(23, "hello") @endcode
1630 ///
1631 /// \param StartLoc The first location of the expression.
1632 /// \param UseGlobal True if 'new' was prefixed with '::'.
1633 /// \param PlacementLParen Opening paren of the placement arguments.
1634 /// \param PlacementArgs Placement new arguments.
1635 /// \param PlacementRParen Closing paren of the placement arguments.
1636 /// \param TypeIdParens If the type is in parens, the source range.
1637 /// \param D The type to be allocated, as well as array dimensions.
1638 /// \param Initializer The initializing expression or initializer-list, or null
1639 /// if there is none.
1640 ExprResult
1641 Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
1642  SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
1643  SourceLocation PlacementRParen, SourceRange TypeIdParens,
1644  Declarator &D, Expr *Initializer) {
1645  Optional<Expr *> ArraySize;
1646  // If the specified type is an array, unwrap it and save the expression.
1647  if (D.getNumTypeObjects() > 0 &&
1649  DeclaratorChunk &Chunk = D.getTypeObject(0);
1650  if (D.getDeclSpec().hasAutoTypeSpec())
1651  return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto)
1652  << D.getSourceRange());
1653  if (Chunk.Arr.hasStatic)
1654  return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
1655  << D.getSourceRange());
1656  if (!Chunk.Arr.NumElts && !Initializer)
1657  return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
1658  << D.getSourceRange());
1659 
1660  ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
1661  D.DropFirstTypeObject();
1662  }
1663 
1664  // Every dimension shall be of constant size.
1665  if (ArraySize) {
1666  for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
1668  break;
1669 
1671  if (Expr *NumElts = (Expr *)Array.NumElts) {
1672  if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
1673  if (getLangOpts().CPlusPlus14) {
1674  // C++1y [expr.new]p6: Every constant-expression in a noptr-new-declarator
1675  // shall be a converted constant expression (5.19) of type std::size_t
1676  // and shall evaluate to a strictly positive value.
1677  unsigned IntWidth = Context.getTargetInfo().getIntWidth();
1678  assert(IntWidth && "Builtin type of size 0?");
1679  llvm::APSInt Value(IntWidth);
1680  Array.NumElts
1682  CCEK_NewExpr)
1683  .get();
1684  } else {
1685  Array.NumElts
1686  = VerifyIntegerConstantExpression(NumElts, nullptr,
1687  diag::err_new_array_nonconst)
1688  .get();
1689  }
1690  if (!Array.NumElts)
1691  return ExprError();
1692  }
1693  }
1694  }
1695  }
1696 
1697  TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/nullptr);
1698  QualType AllocType = TInfo->getType();
1699  if (D.isInvalidType())
1700  return ExprError();
1701 
1702  SourceRange DirectInitRange;
1703  if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer))
1704  DirectInitRange = List->getSourceRange();
1705 
1706  return BuildCXXNew(SourceRange(StartLoc, D.getEndLoc()), UseGlobal,
1707  PlacementLParen, PlacementArgs, PlacementRParen,
1708  TypeIdParens, AllocType, TInfo, ArraySize, DirectInitRange,
1709  Initializer);
1710 }
1711 
1713  Expr *Init) {
1714  if (!Init)
1715  return true;
1716  if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init))
1717  return PLE->getNumExprs() == 0;
1718  if (isa<ImplicitValueInitExpr>(Init))
1719  return true;
1720  else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init))
1721  return !CCE->isListInitialization() &&
1722  CCE->getConstructor()->isDefaultConstructor();
1723  else if (Style == CXXNewExpr::ListInit) {
1724  assert(isa<InitListExpr>(Init) &&
1725  "Shouldn't create list CXXConstructExprs for arrays.");
1726  return true;
1727  }
1728  return false;
1729 }
1730 
1731 bool
1733  if (!getLangOpts().AlignedAllocationUnavailable)
1734  return false;
1735  if (FD.isDefined())
1736  return false;
1737  bool IsAligned = false;
1738  if (FD.isReplaceableGlobalAllocationFunction(&IsAligned) && IsAligned)
1739  return true;
1740  return false;
1741 }
1742 
1743 // Emit a diagnostic if an aligned allocation/deallocation function that is not
1744 // implemented in the standard library is selected.
1746  SourceLocation Loc) {
1748  const llvm::Triple &T = getASTContext().getTargetInfo().getTriple();
1749  StringRef OSName = AvailabilityAttr::getPlatformNameSourceSpelling(
1750  getASTContext().getTargetInfo().getPlatformName());
1751 
1753  bool IsDelete = Kind == OO_Delete || Kind == OO_Array_Delete;
1754  Diag(Loc, diag::err_aligned_allocation_unavailable)
1755  << IsDelete << FD.getType().getAsString() << OSName
1756  << alignedAllocMinVersion(T.getOS()).getAsString();
1757  Diag(Loc, diag::note_silence_aligned_allocation_unavailable);
1758  }
1759 }
1760 
1761 ExprResult
1762 Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
1763  SourceLocation PlacementLParen,
1764  MultiExprArg PlacementArgs,
1765  SourceLocation PlacementRParen,
1766  SourceRange TypeIdParens,
1767  QualType AllocType,
1768  TypeSourceInfo *AllocTypeInfo,
1769  Optional<Expr *> ArraySize,
1770  SourceRange DirectInitRange,
1771  Expr *Initializer) {
1772  SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange();
1773  SourceLocation StartLoc = Range.getBegin();
1774 
1776  if (DirectInitRange.isValid()) {
1777  assert(Initializer && "Have parens but no initializer.");
1778  initStyle = CXXNewExpr::CallInit;
1779  } else if (Initializer && isa<InitListExpr>(Initializer))
1780  initStyle = CXXNewExpr::ListInit;
1781  else {
1782  assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) ||
1783  isa<CXXConstructExpr>(Initializer)) &&
1784  "Initializer expression that cannot have been implicitly created.");
1785  initStyle = CXXNewExpr::NoInit;
1786  }
1787 
1788  Expr **Inits = &Initializer;
1789  unsigned NumInits = Initializer ? 1 : 0;
1790  if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) {
1791  assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init");
1792  Inits = List->getExprs();
1793  NumInits = List->getNumExprs();
1794  }
1795 
1796  // C++11 [expr.new]p15:
1797  // A new-expression that creates an object of type T initializes that
1798  // object as follows:
1800  // - If the new-initializer is omitted, the object is default-
1801  // initialized (8.5); if no initialization is performed,
1802  // the object has indeterminate value
1803  = initStyle == CXXNewExpr::NoInit
1805  // - Otherwise, the new-initializer is interpreted according to
1806  // the
1807  // initialization rules of 8.5 for direct-initialization.
1808  : initStyle == CXXNewExpr::ListInit
1810  TypeRange.getBegin(), Initializer->getBeginLoc(),
1811  Initializer->getEndLoc())
1813  DirectInitRange.getBegin(),
1814  DirectInitRange.getEnd());
1815 
1816  // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
1817  auto *Deduced = AllocType->getContainedDeducedType();
1818  if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
1819  if (ArraySize)
1820  return ExprError(
1821  Diag(ArraySize ? (*ArraySize)->getExprLoc() : TypeRange.getBegin(),
1822  diag::err_deduced_class_template_compound_type)
1823  << /*array*/ 2
1824  << (ArraySize ? (*ArraySize)->getSourceRange() : TypeRange));
1825 
1826  InitializedEntity Entity
1827  = InitializedEntity::InitializeNew(StartLoc, AllocType);
1829  AllocTypeInfo, Entity, Kind, MultiExprArg(Inits, NumInits));
1830  if (AllocType.isNull())
1831  return ExprError();
1832  } else if (Deduced) {
1833  bool Braced = (initStyle == CXXNewExpr::ListInit);
1834  if (NumInits == 1) {
1835  if (auto p = dyn_cast_or_null<InitListExpr>(Inits[0])) {
1836  Inits = p->getInits();
1837  NumInits = p->getNumInits();
1838  Braced = true;
1839  }
1840  }
1841 
1842  if (initStyle == CXXNewExpr::NoInit || NumInits == 0)
1843  return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg)
1844  << AllocType << TypeRange);
1845  if (NumInits > 1) {
1846  Expr *FirstBad = Inits[1];
1847  return ExprError(Diag(FirstBad->getBeginLoc(),
1848  diag::err_auto_new_ctor_multiple_expressions)
1849  << AllocType << TypeRange);
1850  }
1851  if (Braced && !getLangOpts().CPlusPlus17)
1852  Diag(Initializer->getBeginLoc(), diag::ext_auto_new_list_init)
1853  << AllocType << TypeRange;
1854  Expr *Deduce = Inits[0];
1856  if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed)
1857  return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure)
1858  << AllocType << Deduce->getType()
1859  << TypeRange << Deduce->getSourceRange());
1860  if (DeducedType.isNull())
1861  return ExprError();
1862  AllocType = DeducedType;
1863  }
1864 
1865  // Per C++0x [expr.new]p5, the type being constructed may be a
1866  // typedef of an array type.
1867  if (!ArraySize) {
1868  if (const ConstantArrayType *Array
1869  = Context.getAsConstantArrayType(AllocType)) {
1870  ArraySize = IntegerLiteral::Create(Context, Array->getSize(),
1871  Context.getSizeType(),
1872  TypeRange.getEnd());
1873  AllocType = Array->getElementType();
1874  }
1875  }
1876 
1877  if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange))
1878  return ExprError();
1879 
1880  // In ARC, infer 'retaining' for the allocated
1881  if (getLangOpts().ObjCAutoRefCount &&
1882  AllocType.getObjCLifetime() == Qualifiers::OCL_None &&
1883  AllocType->isObjCLifetimeType()) {
1884  AllocType = Context.getLifetimeQualifiedType(AllocType,
1885  AllocType->getObjCARCImplicitLifetime());
1886  }
1887 
1888  QualType ResultType = Context.getPointerType(AllocType);
1889 
1890  if (ArraySize && *ArraySize &&
1891  (*ArraySize)->getType()->isNonOverloadPlaceholderType()) {
1892  ExprResult result = CheckPlaceholderExpr(*ArraySize);
1893  if (result.isInvalid()) return ExprError();
1894  ArraySize = result.get();
1895  }
1896  // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have
1897  // integral or enumeration type with a non-negative value."
1898  // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped
1899  // enumeration type, or a class type for which a single non-explicit
1900  // conversion function to integral or unscoped enumeration type exists.
1901  // C++1y [expr.new]p6: The expression [...] is implicitly converted to
1902  // std::size_t.
1903  llvm::Optional<uint64_t> KnownArraySize;
1904  if (ArraySize && *ArraySize && !(*ArraySize)->isTypeDependent()) {
1905  ExprResult ConvertedSize;
1906  if (getLangOpts().CPlusPlus14) {
1907  assert(Context.getTargetInfo().getIntWidth() && "Builtin type of size 0?");
1908 
1909  ConvertedSize = PerformImplicitConversion(*ArraySize, Context.getSizeType(),
1910  AA_Converting);
1911 
1912  if (!ConvertedSize.isInvalid() &&
1913  (*ArraySize)->getType()->getAs<RecordType>())
1914  // Diagnose the compatibility of this conversion.
1915  Diag(StartLoc, diag::warn_cxx98_compat_array_size_conversion)
1916  << (*ArraySize)->getType() << 0 << "'size_t'";
1917  } else {
1918  class SizeConvertDiagnoser : public ICEConvertDiagnoser {
1919  protected:
1920  Expr *ArraySize;
1921 
1922  public:
1923  SizeConvertDiagnoser(Expr *ArraySize)
1924  : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false, false, false),
1925  ArraySize(ArraySize) {}
1926 
1927  SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
1928  QualType T) override {
1929  return S.Diag(Loc, diag::err_array_size_not_integral)
1930  << S.getLangOpts().CPlusPlus11 << T;
1931  }
1932 
1933  SemaDiagnosticBuilder diagnoseIncomplete(
1934  Sema &S, SourceLocation Loc, QualType T) override {
1935  return S.Diag(Loc, diag::err_array_size_incomplete_type)
1936  << T << ArraySize->getSourceRange();
1937  }
1938 
1939  SemaDiagnosticBuilder diagnoseExplicitConv(
1940  Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
1941  return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy;
1942  }
1943 
1944  SemaDiagnosticBuilder noteExplicitConv(
1945  Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1946  return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1947  << ConvTy->isEnumeralType() << ConvTy;
1948  }
1949 
1950  SemaDiagnosticBuilder diagnoseAmbiguous(
1951  Sema &S, SourceLocation Loc, QualType T) override {
1952  return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T;
1953  }
1954 
1955  SemaDiagnosticBuilder noteAmbiguous(
1956  Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1957  return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1958  << ConvTy->isEnumeralType() << ConvTy;
1959  }
1960 
1961  SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
1962  QualType T,
1963  QualType ConvTy) override {
1964  return S.Diag(Loc,
1965  S.getLangOpts().CPlusPlus11
1966  ? diag::warn_cxx98_compat_array_size_conversion
1967  : diag::ext_array_size_conversion)
1968  << T << ConvTy->isEnumeralType() << ConvTy;
1969  }
1970  } SizeDiagnoser(*ArraySize);
1971 
1972  ConvertedSize = PerformContextualImplicitConversion(StartLoc, *ArraySize,
1973  SizeDiagnoser);
1974  }
1975  if (ConvertedSize.isInvalid())
1976  return ExprError();
1977 
1978  ArraySize = ConvertedSize.get();
1979  QualType SizeType = (*ArraySize)->getType();
1980 
1981  if (!SizeType->isIntegralOrUnscopedEnumerationType())
1982  return ExprError();
1983 
1984  // C++98 [expr.new]p7:
1985  // The expression in a direct-new-declarator shall have integral type
1986  // with a non-negative value.
1987  //
1988  // Let's see if this is a constant < 0. If so, we reject it out of hand,
1989  // per CWG1464. Otherwise, if it's not a constant, we must have an
1990  // unparenthesized array type.
1991  if (!(*ArraySize)->isValueDependent()) {
1993  // We've already performed any required implicit conversion to integer or
1994  // unscoped enumeration type.
1995  // FIXME: Per CWG1464, we are required to check the value prior to
1996  // converting to size_t. This will never find a negative array size in
1997  // C++14 onwards, because Value is always unsigned here!
1998  if ((*ArraySize)->isIntegerConstantExpr(Value, Context)) {
1999  if (Value.isSigned() && Value.isNegative()) {
2000  return ExprError(Diag((*ArraySize)->getBeginLoc(),
2001  diag::err_typecheck_negative_array_size)
2002  << (*ArraySize)->getSourceRange());
2003  }
2004 
2005  if (!AllocType->isDependentType()) {
2006  unsigned ActiveSizeBits =
2008  if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context))
2009  return ExprError(
2010  Diag((*ArraySize)->getBeginLoc(), diag::err_array_too_large)
2011  << Value.toString(10) << (*ArraySize)->getSourceRange());
2012  }
2013 
2014  KnownArraySize = Value.getZExtValue();
2015  } else if (TypeIdParens.isValid()) {
2016  // Can't have dynamic array size when the type-id is in parentheses.
2017  Diag((*ArraySize)->getBeginLoc(), diag::ext_new_paren_array_nonconst)
2018  << (*ArraySize)->getSourceRange()
2019  << FixItHint::CreateRemoval(TypeIdParens.getBegin())
2020  << FixItHint::CreateRemoval(TypeIdParens.getEnd());
2021 
2022  TypeIdParens = SourceRange();
2023  }
2024  }
2025 
2026  // Note that we do *not* convert the argument in any way. It can
2027  // be signed, larger than size_t, whatever.
2028  }
2029 
2030  FunctionDecl *OperatorNew = nullptr;
2031  FunctionDecl *OperatorDelete = nullptr;
2032  unsigned Alignment =
2033  AllocType->isDependentType() ? 0 : Context.getTypeAlign(AllocType);
2034  unsigned NewAlignment = Context.getTargetInfo().getNewAlign();
2035  bool PassAlignment = getLangOpts().AlignedAllocation &&
2036  Alignment > NewAlignment;
2037 
2039  if (!AllocType->isDependentType() &&
2040  !Expr::hasAnyTypeDependentArguments(PlacementArgs) &&
2042  StartLoc, SourceRange(PlacementLParen, PlacementRParen), Scope, Scope,
2043  AllocType, ArraySize.hasValue(), PassAlignment, PlacementArgs,
2044  OperatorNew, OperatorDelete))
2045  return ExprError();
2046 
2047  // If this is an array allocation, compute whether the usual array
2048  // deallocation function for the type has a size_t parameter.
2049  bool UsualArrayDeleteWantsSize = false;
2050  if (ArraySize && !AllocType->isDependentType())
2051  UsualArrayDeleteWantsSize =
2052  doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType);
2053 
2054  SmallVector<Expr *, 8> AllPlaceArgs;
2055  if (OperatorNew) {
2056  const FunctionProtoType *Proto =
2057  OperatorNew->getType()->getAs<FunctionProtoType>();
2058  VariadicCallType CallType = Proto->isVariadic() ? VariadicFunction
2060 
2061  // We've already converted the placement args, just fill in any default
2062  // arguments. Skip the first parameter because we don't have a corresponding
2063  // argument. Skip the second parameter too if we're passing in the
2064  // alignment; we've already filled it in.
2065  if (GatherArgumentsForCall(PlacementLParen, OperatorNew, Proto,
2066  PassAlignment ? 2 : 1, PlacementArgs,
2067  AllPlaceArgs, CallType))
2068  return ExprError();
2069 
2070  if (!AllPlaceArgs.empty())
2071  PlacementArgs = AllPlaceArgs;
2072 
2073  // FIXME: This is wrong: PlacementArgs misses out the first (size) argument.
2074  DiagnoseSentinelCalls(OperatorNew, PlacementLParen, PlacementArgs);
2075 
2076  // FIXME: Missing call to CheckFunctionCall or equivalent
2077 
2078  // Warn if the type is over-aligned and is being allocated by (unaligned)
2079  // global operator new.
2080  if (PlacementArgs.empty() && !PassAlignment &&
2081  (OperatorNew->isImplicit() ||
2082  (OperatorNew->getBeginLoc().isValid() &&
2083  getSourceManager().isInSystemHeader(OperatorNew->getBeginLoc())))) {
2084  if (Alignment > NewAlignment)
2085  Diag(StartLoc, diag::warn_overaligned_type)
2086  << AllocType
2087  << unsigned(Alignment / Context.getCharWidth())
2088  << unsigned(NewAlignment / Context.getCharWidth());
2089  }
2090  }
2091 
2092  // Array 'new' can't have any initializers except empty parentheses.
2093  // Initializer lists are also allowed, in C++11. Rely on the parser for the
2094  // dialect distinction.
2095  if (ArraySize && !isLegalArrayNewInitializer(initStyle, Initializer)) {
2096  SourceRange InitRange(Inits[0]->getBeginLoc(),
2097  Inits[NumInits - 1]->getEndLoc());
2098  Diag(StartLoc, diag::err_new_array_init_args) << InitRange;
2099  return ExprError();
2100  }
2101 
2102  // If we can perform the initialization, and we've not already done so,
2103  // do it now.
2104  if (!AllocType->isDependentType() &&
2106  llvm::makeArrayRef(Inits, NumInits))) {
2107  // The type we initialize is the complete type, including the array bound.
2108  QualType InitType;
2109  if (KnownArraySize)
2110  InitType = Context.getConstantArrayType(
2112  *KnownArraySize),
2113  ArrayType::Normal, 0);
2114  else if (ArraySize)
2115  InitType =
2117  else
2118  InitType = AllocType;
2119 
2120  InitializedEntity Entity
2121  = InitializedEntity::InitializeNew(StartLoc, InitType);
2122  InitializationSequence InitSeq(*this, Entity, Kind,
2123  MultiExprArg(Inits, NumInits));
2124  ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind,
2125  MultiExprArg(Inits, NumInits));
2126  if (FullInit.isInvalid())
2127  return ExprError();
2128 
2129  // FullInit is our initializer; strip off CXXBindTemporaryExprs, because
2130  // we don't want the initialized object to be destructed.
2131  // FIXME: We should not create these in the first place.
2132  if (CXXBindTemporaryExpr *Binder =
2133  dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get()))
2134  FullInit = Binder->getSubExpr();
2135 
2136  Initializer = FullInit.get();
2137 
2138  // FIXME: If we have a KnownArraySize, check that the array bound of the
2139  // initializer is no greater than that constant value.
2140 
2141  if (ArraySize && !*ArraySize) {
2142  auto *CAT = Context.getAsConstantArrayType(Initializer->getType());
2143  if (CAT) {
2144  // FIXME: Track that the array size was inferred rather than explicitly
2145  // specified.
2146  ArraySize = IntegerLiteral::Create(
2147  Context, CAT->getSize(), Context.getSizeType(), TypeRange.getEnd());
2148  } else {
2149  Diag(TypeRange.getEnd(), diag::err_new_array_size_unknown_from_init)
2150  << Initializer->getSourceRange();
2151  }
2152  }
2153  }
2154 
2155  // Mark the new and delete operators as referenced.
2156  if (OperatorNew) {
2157  if (DiagnoseUseOfDecl(OperatorNew, StartLoc))
2158  return ExprError();
2159  MarkFunctionReferenced(StartLoc, OperatorNew);
2160  }
2161  if (OperatorDelete) {
2162  if (DiagnoseUseOfDecl(OperatorDelete, StartLoc))
2163  return ExprError();
2164  MarkFunctionReferenced(StartLoc, OperatorDelete);
2165  }
2166 
2167  return CXXNewExpr::Create(Context, UseGlobal, OperatorNew, OperatorDelete,
2168  PassAlignment, UsualArrayDeleteWantsSize,
2169  PlacementArgs, TypeIdParens, ArraySize, initStyle,
2170  Initializer, ResultType, AllocTypeInfo, Range,
2171  DirectInitRange);
2172 }
2173 
2174 /// Checks that a type is suitable as the allocated type
2175 /// in a new-expression.
2177  SourceRange R) {
2178  // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
2179  // abstract class type or array thereof.
2180  if (AllocType->isFunctionType())
2181  return Diag(Loc, diag::err_bad_new_type)
2182  << AllocType << 0 << R;
2183  else if (AllocType->isReferenceType())
2184  return Diag(Loc, diag::err_bad_new_type)
2185  << AllocType << 1 << R;
2186  else if (!AllocType->isDependentType() &&
2187  RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R))
2188  return true;
2189  else if (RequireNonAbstractType(Loc, AllocType,
2190  diag::err_allocation_of_abstract_type))
2191  return true;
2192  else if (AllocType->isVariablyModifiedType())
2193  return Diag(Loc, diag::err_variably_modified_new_type)
2194  << AllocType;
2195  else if (AllocType.getAddressSpace() != LangAS::Default &&
2196  !getLangOpts().OpenCLCPlusPlus)
2197  return Diag(Loc, diag::err_address_space_qualified_new)
2198  << AllocType.getUnqualifiedType()
2200  else if (getLangOpts().ObjCAutoRefCount) {
2201  if (const ArrayType *AT = Context.getAsArrayType(AllocType)) {
2202  QualType BaseAllocType = Context.getBaseElementType(AT);
2203  if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None &&
2204  BaseAllocType->isObjCLifetimeType())
2205  return Diag(Loc, diag::err_arc_new_array_without_ownership)
2206  << BaseAllocType;
2207  }
2208  }
2209 
2210  return false;
2211 }
2212 
2215  bool &PassAlignment, FunctionDecl *&Operator,
2216  OverloadCandidateSet *AlignedCandidates, Expr *AlignArg, bool Diagnose) {
2217  OverloadCandidateSet Candidates(R.getNameLoc(),
2219  for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
2220  Alloc != AllocEnd; ++Alloc) {
2221  // Even member operator new/delete are implicitly treated as
2222  // static, so don't use AddMemberCandidate.
2223  NamedDecl *D = (*Alloc)->getUnderlyingDecl();
2224 
2225  if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
2226  S.AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(),
2227  /*ExplicitTemplateArgs=*/nullptr, Args,
2228  Candidates,
2229  /*SuppressUserConversions=*/false);
2230  continue;
2231  }
2232 
2233  FunctionDecl *Fn = cast<FunctionDecl>(D);
2234  S.AddOverloadCandidate(Fn, Alloc.getPair(), Args, Candidates,
2235  /*SuppressUserConversions=*/false);
2236  }
2237 
2238  // Do the resolution.
2240  switch (Candidates.BestViableFunction(S, R.getNameLoc(), Best)) {
2241  case OR_Success: {
2242  // Got one!
2243  FunctionDecl *FnDecl = Best->Function;
2244  if (S.CheckAllocationAccess(R.getNameLoc(), Range, R.getNamingClass(),
2245  Best->FoundDecl) == Sema::AR_inaccessible)
2246  return true;
2247 
2248  Operator = FnDecl;
2249  return false;
2250  }
2251 
2252  case OR_No_Viable_Function:
2253  // C++17 [expr.new]p13:
2254  // If no matching function is found and the allocated object type has
2255  // new-extended alignment, the alignment argument is removed from the
2256  // argument list, and overload resolution is performed again.
2257  if (PassAlignment) {
2258  PassAlignment = false;
2259  AlignArg = Args[1];
2260  Args.erase(Args.begin() + 1);
2261  return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2262  Operator, &Candidates, AlignArg,
2263  Diagnose);
2264  }
2265 
2266  // MSVC will fall back on trying to find a matching global operator new
2267  // if operator new[] cannot be found. Also, MSVC will leak by not
2268  // generating a call to operator delete or operator delete[], but we
2269  // will not replicate that bug.
2270  // FIXME: Find out how this interacts with the std::align_val_t fallback
2271  // once MSVC implements it.
2272  if (R.getLookupName().getCXXOverloadedOperator() == OO_Array_New &&
2273  S.Context.getLangOpts().MSVCCompat) {
2274  R.clear();
2277  // FIXME: This will give bad diagnostics pointing at the wrong functions.
2278  return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2279  Operator, /*Candidates=*/nullptr,
2280  /*AlignArg=*/nullptr, Diagnose);
2281  }
2282 
2283  if (Diagnose) {
2284  PartialDiagnosticAt PD(R.getNameLoc(), S.PDiag(diag::err_ovl_no_viable_function_in_call)
2285  << R.getLookupName() << Range);
2286 
2287  // If we have aligned candidates, only note the align_val_t candidates
2288  // from AlignedCandidates and the non-align_val_t candidates from
2289  // Candidates.
2290  if (AlignedCandidates) {
2291  auto IsAligned = [](OverloadCandidate &C) {
2292  return C.Function->getNumParams() > 1 &&
2293  C.Function->getParamDecl(1)->getType()->isAlignValT();
2294  };
2295  auto IsUnaligned = [&](OverloadCandidate &C) { return !IsAligned(C); };
2296 
2297  // This was an overaligned allocation, so list the aligned candidates
2298  // first.
2299  Args.insert(Args.begin() + 1, AlignArg);
2300  AlignedCandidates->NoteCandidates(PD, S, OCD_AllCandidates, Args, "",
2301  R.getNameLoc(), IsAligned);
2302  Args.erase(Args.begin() + 1);
2303  Candidates.NoteCandidates(PD, S, OCD_AllCandidates, Args, "", R.getNameLoc(),
2304  IsUnaligned);
2305  } else {
2306  Candidates.NoteCandidates(PD, S, OCD_AllCandidates, Args);
2307  }
2308  }
2309  return true;
2310 
2311  case OR_Ambiguous:
2312  if (Diagnose) {
2313  Candidates.NoteCandidates(
2315  S.PDiag(diag::err_ovl_ambiguous_call)
2316  << R.getLookupName() << Range),
2317  S, OCD_ViableCandidates, Args);
2318  }
2319  return true;
2320 
2321  case OR_Deleted: {
2322  if (Diagnose) {
2323  Candidates.NoteCandidates(
2325  S.PDiag(diag::err_ovl_deleted_call)
2326  << R.getLookupName() << Range),
2327  S, OCD_AllCandidates, Args);
2328  }
2329  return true;
2330  }
2331  }
2332  llvm_unreachable("Unreachable, bad result from BestViableFunction");
2333 }
2334 
2336  AllocationFunctionScope NewScope,
2337  AllocationFunctionScope DeleteScope,
2338  QualType AllocType, bool IsArray,
2339  bool &PassAlignment, MultiExprArg PlaceArgs,
2340  FunctionDecl *&OperatorNew,
2341  FunctionDecl *&OperatorDelete,
2342  bool Diagnose) {
2343  // --- Choosing an allocation function ---
2344  // C++ 5.3.4p8 - 14 & 18
2345  // 1) If looking in AFS_Global scope for allocation functions, only look in
2346  // the global scope. Else, if AFS_Class, only look in the scope of the
2347  // allocated class. If AFS_Both, look in both.
2348  // 2) If an array size is given, look for operator new[], else look for
2349  // operator new.
2350  // 3) The first argument is always size_t. Append the arguments from the
2351  // placement form.
2352 
2353  SmallVector<Expr*, 8> AllocArgs;
2354  AllocArgs.reserve((PassAlignment ? 2 : 1) + PlaceArgs.size());
2355 
2356  // We don't care about the actual value of these arguments.
2357  // FIXME: Should the Sema create the expression and embed it in the syntax
2358  // tree? Or should the consumer just recalculate the value?
2359  // FIXME: Using a dummy value will interact poorly with attribute enable_if.
2360  IntegerLiteral Size(Context, llvm::APInt::getNullValue(
2362  Context.getSizeType(),
2363  SourceLocation());
2364  AllocArgs.push_back(&Size);
2365 
2366  QualType AlignValT = Context.VoidTy;
2367  if (PassAlignment) {
2369  AlignValT = Context.getTypeDeclType(getStdAlignValT());
2370  }
2371  CXXScalarValueInitExpr Align(AlignValT, nullptr, SourceLocation());
2372  if (PassAlignment)
2373  AllocArgs.push_back(&Align);
2374 
2375  AllocArgs.insert(AllocArgs.end(), PlaceArgs.begin(), PlaceArgs.end());
2376 
2377  // C++ [expr.new]p8:
2378  // If the allocated type is a non-array type, the allocation
2379  // function's name is operator new and the deallocation function's
2380  // name is operator delete. If the allocated type is an array
2381  // type, the allocation function's name is operator new[] and the
2382  // deallocation function's name is operator delete[].
2384  IsArray ? OO_Array_New : OO_New);
2385 
2386  QualType AllocElemType = Context.getBaseElementType(AllocType);
2387 
2388  // Find the allocation function.
2389  {
2390  LookupResult R(*this, NewName, StartLoc, LookupOrdinaryName);
2391 
2392  // C++1z [expr.new]p9:
2393  // If the new-expression begins with a unary :: operator, the allocation
2394  // function's name is looked up in the global scope. Otherwise, if the
2395  // allocated type is a class type T or array thereof, the allocation
2396  // function's name is looked up in the scope of T.
2397  if (AllocElemType->isRecordType() && NewScope != AFS_Global)
2398  LookupQualifiedName(R, AllocElemType->getAsCXXRecordDecl());
2399 
2400  // We can see ambiguity here if the allocation function is found in
2401  // multiple base classes.
2402  if (R.isAmbiguous())
2403  return true;
2404 
2405  // If this lookup fails to find the name, or if the allocated type is not
2406  // a class type, the allocation function's name is looked up in the
2407  // global scope.
2408  if (R.empty()) {
2409  if (NewScope == AFS_Class)
2410  return true;
2411 
2413  }
2414 
2415  if (getLangOpts().OpenCLCPlusPlus && R.empty()) {
2416  if (PlaceArgs.empty()) {
2417  Diag(StartLoc, diag::err_openclcxx_not_supported) << "default new";
2418  } else {
2419  Diag(StartLoc, diag::err_openclcxx_placement_new);
2420  }
2421  return true;
2422  }
2423 
2424  assert(!R.empty() && "implicitly declared allocation functions not found");
2425  assert(!R.isAmbiguous() && "global allocation functions are ambiguous");
2426 
2427  // We do our own custom access checks below.
2428  R.suppressDiagnostics();
2429 
2430  if (resolveAllocationOverload(*this, R, Range, AllocArgs, PassAlignment,
2431  OperatorNew, /*Candidates=*/nullptr,
2432  /*AlignArg=*/nullptr, Diagnose))
2433  return true;
2434  }
2435 
2436  // We don't need an operator delete if we're running under -fno-exceptions.
2437  if (!getLangOpts().Exceptions) {
2438  OperatorDelete = nullptr;
2439  return false;
2440  }
2441 
2442  // Note, the name of OperatorNew might have been changed from array to
2443  // non-array by resolveAllocationOverload.
2445  OperatorNew->getDeclName().getCXXOverloadedOperator() == OO_Array_New
2446  ? OO_Array_Delete
2447  : OO_Delete);
2448 
2449  // C++ [expr.new]p19:
2450  //
2451  // If the new-expression begins with a unary :: operator, the
2452  // deallocation function's name is looked up in the global
2453  // scope. Otherwise, if the allocated type is a class type T or an
2454  // array thereof, the deallocation function's name is looked up in
2455  // the scope of T. If this lookup fails to find the name, or if
2456  // the allocated type is not a class type or array thereof, the
2457  // deallocation function's name is looked up in the global scope.
2458  LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName);
2459  if (AllocElemType->isRecordType() && DeleteScope != AFS_Global) {
2460  CXXRecordDecl *RD
2461  = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl());
2462  LookupQualifiedName(FoundDelete, RD);
2463  }
2464  if (FoundDelete.isAmbiguous())
2465  return true; // FIXME: clean up expressions?
2466 
2467  bool FoundGlobalDelete = FoundDelete.empty();
2468  if (FoundDelete.empty()) {
2469  if (DeleteScope == AFS_Class)
2470  return true;
2471 
2474  }
2475 
2476  FoundDelete.suppressDiagnostics();
2477 
2479 
2480  // Whether we're looking for a placement operator delete is dictated
2481  // by whether we selected a placement operator new, not by whether
2482  // we had explicit placement arguments. This matters for things like
2483  // struct A { void *operator new(size_t, int = 0); ... };
2484  // A *a = new A()
2485  //
2486  // We don't have any definition for what a "placement allocation function"
2487  // is, but we assume it's any allocation function whose
2488  // parameter-declaration-clause is anything other than (size_t).
2489  //
2490  // FIXME: Should (size_t, std::align_val_t) also be considered non-placement?
2491  // This affects whether an exception from the constructor of an overaligned
2492  // type uses the sized or non-sized form of aligned operator delete.
2493  bool isPlacementNew = !PlaceArgs.empty() || OperatorNew->param_size() != 1 ||
2494  OperatorNew->isVariadic();
2495 
2496  if (isPlacementNew) {
2497  // C++ [expr.new]p20:
2498  // A declaration of a placement deallocation function matches the
2499  // declaration of a placement allocation function if it has the
2500  // same number of parameters and, after parameter transformations
2501  // (8.3.5), all parameter types except the first are
2502  // identical. [...]
2503  //
2504  // To perform this comparison, we compute the function type that
2505  // the deallocation function should have, and use that type both
2506  // for template argument deduction and for comparison purposes.
2507  QualType ExpectedFunctionType;
2508  {
2509  const FunctionProtoType *Proto
2510  = OperatorNew->getType()->getAs<FunctionProtoType>();
2511 
2512  SmallVector<QualType, 4> ArgTypes;
2513  ArgTypes.push_back(Context.VoidPtrTy);
2514  for (unsigned I = 1, N = Proto->getNumParams(); I < N; ++I)
2515  ArgTypes.push_back(Proto->getParamType(I));
2516 
2518  // FIXME: This is not part of the standard's rule.
2519  EPI.Variadic = Proto->isVariadic();
2520 
2521  ExpectedFunctionType
2522  = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI);
2523  }
2524 
2525  for (LookupResult::iterator D = FoundDelete.begin(),
2526  DEnd = FoundDelete.end();
2527  D != DEnd; ++D) {
2528  FunctionDecl *Fn = nullptr;
2529  if (FunctionTemplateDecl *FnTmpl =
2530  dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) {
2531  // Perform template argument deduction to try to match the
2532  // expected function type.
2533  TemplateDeductionInfo Info(StartLoc);
2534  if (DeduceTemplateArguments(FnTmpl, nullptr, ExpectedFunctionType, Fn,
2535  Info))
2536  continue;
2537  } else
2538  Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl());
2539 
2541  ExpectedFunctionType,
2542  /*AdjustExcpetionSpec*/true),
2543  ExpectedFunctionType))
2544  Matches.push_back(std::make_pair(D.getPair(), Fn));
2545  }
2546 
2547  if (getLangOpts().CUDA)
2548  EraseUnwantedCUDAMatches(dyn_cast<FunctionDecl>(CurContext), Matches);
2549  } else {
2550  // C++1y [expr.new]p22:
2551  // For a non-placement allocation function, the normal deallocation
2552  // function lookup is used
2553  //
2554  // Per [expr.delete]p10, this lookup prefers a member operator delete
2555  // without a size_t argument, but prefers a non-member operator delete
2556  // with a size_t where possible (which it always is in this case).
2558  UsualDeallocFnInfo Selected = resolveDeallocationOverload(
2559  *this, FoundDelete, /*WantSize*/ FoundGlobalDelete,
2560  /*WantAlign*/ hasNewExtendedAlignment(*this, AllocElemType),
2561  &BestDeallocFns);
2562  if (Selected)
2563  Matches.push_back(std::make_pair(Selected.Found, Selected.FD));
2564  else {
2565  // If we failed to select an operator, all remaining functions are viable
2566  // but ambiguous.
2567  for (auto Fn : BestDeallocFns)
2568  Matches.push_back(std::make_pair(Fn.Found, Fn.FD));
2569  }
2570  }
2571 
2572  // C++ [expr.new]p20:
2573  // [...] If the lookup finds a single matching deallocation
2574  // function, that function will be called; otherwise, no
2575  // deallocation function will be called.
2576  if (Matches.size() == 1) {
2577  OperatorDelete = Matches[0].second;
2578 
2579  // C++1z [expr.new]p23:
2580  // If the lookup finds a usual deallocation function (3.7.4.2)
2581  // with a parameter of type std::size_t and that function, considered
2582  // as a placement deallocation function, would have been
2583  // selected as a match for the allocation function, the program
2584  // is ill-formed.
2585  if (getLangOpts().CPlusPlus11 && isPlacementNew &&
2586  isNonPlacementDeallocationFunction(*this, OperatorDelete)) {
2587  UsualDeallocFnInfo Info(*this,
2588  DeclAccessPair::make(OperatorDelete, AS_public));
2589  // Core issue, per mail to core reflector, 2016-10-09:
2590  // If this is a member operator delete, and there is a corresponding
2591  // non-sized member operator delete, this isn't /really/ a sized
2592  // deallocation function, it just happens to have a size_t parameter.
2593  bool IsSizedDelete = Info.HasSizeT;
2594  if (IsSizedDelete && !FoundGlobalDelete) {
2595  auto NonSizedDelete =
2596  resolveDeallocationOverload(*this, FoundDelete, /*WantSize*/false,
2597  /*WantAlign*/Info.HasAlignValT);
2598  if (NonSizedDelete && !NonSizedDelete.HasSizeT &&
2599  NonSizedDelete.HasAlignValT == Info.HasAlignValT)
2600  IsSizedDelete = false;
2601  }
2602 
2603  if (IsSizedDelete) {
2604  SourceRange R = PlaceArgs.empty()
2605  ? SourceRange()
2606  : SourceRange(PlaceArgs.front()->getBeginLoc(),
2607  PlaceArgs.back()->getEndLoc());
2608  Diag(StartLoc, diag::err_placement_new_non_placement_delete) << R;
2609  if (!OperatorDelete->isImplicit())
2610  Diag(OperatorDelete->getLocation(), diag::note_previous_decl)
2611  << DeleteName;
2612  }
2613  }
2614 
2615  CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(),
2616  Matches[0].first);
2617  } else if (!Matches.empty()) {
2618  // We found multiple suitable operators. Per [expr.new]p20, that means we
2619  // call no 'operator delete' function, but we should at least warn the user.
2620  // FIXME: Suppress this warning if the construction cannot throw.
2621  Diag(StartLoc, diag::warn_ambiguous_suitable_delete_function_found)
2622  << DeleteName << AllocElemType;
2623 
2624  for (auto &Match : Matches)
2625  Diag(Match.second->getLocation(),
2626  diag::note_member_declared_here) << DeleteName;
2627  }
2628 
2629  return false;
2630 }
2631 
2632 /// DeclareGlobalNewDelete - Declare the global forms of operator new and
2633 /// delete. These are:
2634 /// @code
2635 /// // C++03:
2636 /// void* operator new(std::size_t) throw(std::bad_alloc);
2637 /// void* operator new[](std::size_t) throw(std::bad_alloc);
2638 /// void operator delete(void *) throw();
2639 /// void operator delete[](void *) throw();
2640 /// // C++11:
2641 /// void* operator new(std::size_t);
2642 /// void* operator new[](std::size_t);
2643 /// void operator delete(void *) noexcept;
2644 /// void operator delete[](void *) noexcept;
2645 /// // C++1y:
2646 /// void* operator new(std::size_t);
2647 /// void* operator new[](std::size_t);
2648 /// void operator delete(void *) noexcept;
2649 /// void operator delete[](void *) noexcept;
2650 /// void operator delete(void *, std::size_t) noexcept;
2651 /// void operator delete[](void *, std::size_t) noexcept;
2652 /// @endcode
2653 /// Note that the placement and nothrow forms of new are *not* implicitly
2654 /// declared. Their use requires including <new>.
2657  return;
2658 
2659  // The implicitly declared new and delete operators
2660  // are not supported in OpenCL.
2661  if (getLangOpts().OpenCLCPlusPlus)
2662  return;
2663 
2664  // C++ [basic.std.dynamic]p2:
2665  // [...] The following allocation and deallocation functions (18.4) are
2666  // implicitly declared in global scope in each translation unit of a
2667  // program
2668  //
2669  // C++03:
2670  // void* operator new(std::size_t) throw(std::bad_alloc);
2671  // void* operator new[](std::size_t) throw(std::bad_alloc);
2672  // void operator delete(void*) throw();
2673  // void operator delete[](void*) throw();
2674  // C++11:
2675  // void* operator new(std::size_t);
2676  // void* operator new[](std::size_t);
2677  // void operator delete(void*) noexcept;
2678  // void operator delete[](void*) noexcept;
2679  // C++1y:
2680  // void* operator new(std::size_t);
2681  // void* operator new[](std::size_t);
2682  // void operator delete(void*) noexcept;
2683  // void operator delete[](void*) noexcept;
2684  // void operator delete(void*, std::size_t) noexcept;
2685  // void operator delete[](void*, std::size_t) noexcept;
2686  //
2687  // These implicit declarations introduce only the function names operator
2688  // new, operator new[], operator delete, operator delete[].
2689  //
2690  // Here, we need to refer to std::bad_alloc, so we will implicitly declare
2691  // "std" or "bad_alloc" as necessary to form the exception specification.
2692  // However, we do not make these implicit declarations visible to name
2693  // lookup.
2694  if (!StdBadAlloc && !getLangOpts().CPlusPlus11) {
2695  // The "std::bad_alloc" class has not yet been declared, so build it
2696  // implicitly.
2700  &PP.getIdentifierTable().get("bad_alloc"),
2701  nullptr);
2702  getStdBadAlloc()->setImplicit(true);
2703  }
2704  if (!StdAlignValT && getLangOpts().AlignedAllocation) {
2705  // The "std::align_val_t" enum class has not yet been declared, so build it
2706  // implicitly.
2707  auto *AlignValT = EnumDecl::Create(
2709  &PP.getIdentifierTable().get("align_val_t"), nullptr, true, true, true);
2710  AlignValT->setIntegerType(Context.getSizeType());
2711  AlignValT->setPromotionType(Context.getSizeType());
2712  AlignValT->setImplicit(true);
2713  StdAlignValT = AlignValT;
2714  }
2715 
2716  GlobalNewDeleteDeclared = true;
2717 
2719  QualType SizeT = Context.getSizeType();
2720 
2721  auto DeclareGlobalAllocationFunctions = [&](OverloadedOperatorKind Kind,
2722  QualType Return, QualType Param) {
2724  Params.push_back(Param);
2725 
2726  // Create up to four variants of the function (sized/aligned).
2727  bool HasSizedVariant = getLangOpts().SizedDeallocation &&
2728  (Kind == OO_Delete || Kind == OO_Array_Delete);
2729  bool HasAlignedVariant = getLangOpts().AlignedAllocation;
2730 
2731  int NumSizeVariants = (HasSizedVariant ? 2 : 1);
2732  int NumAlignVariants = (HasAlignedVariant ? 2 : 1);
2733  for (int Sized = 0; Sized < NumSizeVariants; ++Sized) {
2734  if (Sized)
2735  Params.push_back(SizeT);
2736 
2737  for (int Aligned = 0; Aligned < NumAlignVariants; ++Aligned) {
2738  if (Aligned)
2739  Params.push_back(Context.getTypeDeclType(getStdAlignValT()));
2740 
2742  Context.DeclarationNames.getCXXOperatorName(Kind), Return, Params);
2743 
2744  if (Aligned)
2745  Params.pop_back();
2746  }
2747  }
2748  };
2749 
2750  DeclareGlobalAllocationFunctions(OO_New, VoidPtr, SizeT);
2751  DeclareGlobalAllocationFunctions(OO_Array_New, VoidPtr, SizeT);
2752  DeclareGlobalAllocationFunctions(OO_Delete, Context.VoidTy, VoidPtr);
2753  DeclareGlobalAllocationFunctions(OO_Array_Delete, Context.VoidTy, VoidPtr);
2754 }
2755 
2756 /// DeclareGlobalAllocationFunction - Declares a single implicit global
2757 /// allocation function if it doesn't already exist.
2759  QualType Return,
2760  ArrayRef<QualType> Params) {
2762 
2763  // Check if this function is already declared.
2764  DeclContext::lookup_result R = GlobalCtx->lookup(Name);
2765  for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end();
2766  Alloc != AllocEnd; ++Alloc) {
2767  // Only look at non-template functions, as it is the predefined,
2768  // non-templated allocation function we are trying to declare here.
2769  if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
2770  if (Func->getNumParams() == Params.size()) {
2771  llvm::SmallVector<QualType, 3> FuncParams;
2772  for (auto *P : Func->parameters())
2773  FuncParams.push_back(
2774  Context.getCanonicalType(P->getType().getUnqualifiedType()));
2775  if (llvm::makeArrayRef(FuncParams) == Params) {
2776  // Make the function visible to name lookup, even if we found it in
2777  // an unimported module. It either is an implicitly-declared global
2778  // allocation function, or is suppressing that function.
2779  Func->setVisibleDespiteOwningModule();
2780  return;
2781  }
2782  }
2783  }
2784  }
2785 
2787  /*IsVariadic=*/false, /*IsCXXMethod=*/false, /*IsBuiltin=*/true));
2788 
2789  QualType BadAllocType;
2790  bool HasBadAllocExceptionSpec
2791  = (Name.getCXXOverloadedOperator() == OO_New ||
2792  Name.getCXXOverloadedOperator() == OO_Array_New);
2793  if (HasBadAllocExceptionSpec) {
2794  if (!getLangOpts().CPlusPlus11) {
2795  BadAllocType = Context.getTypeDeclType(getStdBadAlloc());
2796  assert(StdBadAlloc && "Must have std::bad_alloc declared");
2797  EPI.ExceptionSpec.Type = EST_Dynamic;
2798  EPI.ExceptionSpec.Exceptions = llvm::makeArrayRef(BadAllocType);
2799  }
2800  } else {
2801  EPI.ExceptionSpec =
2802  getLangOpts().CPlusPlus11 ? EST_BasicNoexcept : EST_DynamicNone;
2803  }
2804 
2805  auto CreateAllocationFunctionDecl = [&](Attr *ExtraAttr) {
2806  QualType FnType = Context.getFunctionType(Return, Params, EPI);
2808  Context, GlobalCtx, SourceLocation(), SourceLocation(), Name,
2809  FnType, /*TInfo=*/nullptr, SC_None, false, true);
2810  Alloc->setImplicit();
2811  // Global allocation functions should always be visible.
2813 
2814  Alloc->addAttr(VisibilityAttr::CreateImplicit(
2815  Context, LangOpts.GlobalAllocationFunctionVisibilityHidden
2816  ? VisibilityAttr::Hidden
2818 
2820  for (QualType T : Params) {
2821  ParamDecls.push_back(ParmVarDecl::Create(
2822  Context, Alloc, SourceLocation(), SourceLocation(), nullptr, T,
2823  /*TInfo=*/nullptr, SC_None, nullptr));
2824  ParamDecls.back()->setImplicit();
2825  }
2826  Alloc->setParams(ParamDecls);
2827  if (ExtraAttr)
2828  Alloc->addAttr(ExtraAttr);
2830  IdResolver.tryAddTopLevelDecl(Alloc, Name);
2831  };
2832 
2833  if (!LangOpts.CUDA)
2834  CreateAllocationFunctionDecl(nullptr);
2835  else {
2836  // Host and device get their own declaration so each can be
2837  // defined or re-declared independently.
2838  CreateAllocationFunctionDecl(CUDAHostAttr::CreateImplicit(Context));
2839  CreateAllocationFunctionDecl(CUDADeviceAttr::CreateImplicit(Context));
2840  }
2841 }
2842 
2844  bool CanProvideSize,
2845  bool Overaligned,
2846  DeclarationName Name) {
2848 
2849  LookupResult FoundDelete(*this, Name, StartLoc, LookupOrdinaryName);
2851 
2852  // FIXME: It's possible for this to result in ambiguity, through a
2853  // user-declared variadic operator delete or the enable_if attribute. We
2854  // should probably not consider those cases to be usual deallocation
2855  // functions. But for now we just make an arbitrary choice in that case.
2856  auto Result = resolveDeallocationOverload(*this, FoundDelete, CanProvideSize,
2857  Overaligned);
2858  assert(Result.FD && "operator delete missing from global scope?");
2859  return Result.FD;
2860 }
2861 
2863  CXXRecordDecl *RD) {
2865 
2866  FunctionDecl *OperatorDelete = nullptr;
2867  if (FindDeallocationFunction(Loc, RD, Name, OperatorDelete))
2868  return nullptr;
2869  if (OperatorDelete)
2870  return OperatorDelete;
2871 
2872  // If there's no class-specific operator delete, look up the global
2873  // non-array delete.
2875  Loc, true, hasNewExtendedAlignment(*this, Context.getRecordType(RD)),
2876  Name);
2877 }
2878 
2880  DeclarationName Name,
2881  FunctionDecl *&Operator, bool Diagnose) {
2882  LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
2883  // Try to find operator delete/operator delete[] in class scope.
2884  LookupQualifiedName(Found, RD);
2885 
2886  if (Found.isAmbiguous())
2887  return true;
2888 
2889  Found.suppressDiagnostics();
2890 
2891  bool Overaligned = hasNewExtendedAlignment(*this, Context.getRecordType(RD));
2892 
2893  // C++17 [expr.delete]p10:
2894  // If the deallocation functions have class scope, the one without a
2895  // parameter of type std::size_t is selected.
2897  resolveDeallocationOverload(*this, Found, /*WantSize*/ false,
2898  /*WantAlign*/ Overaligned, &Matches);
2899 
2900  // If we could find an overload, use it.
2901  if (Matches.size() == 1) {
2902  Operator = cast<CXXMethodDecl>(Matches[0].FD);
2903 
2904  // FIXME: DiagnoseUseOfDecl?
2905  if (Operator->isDeleted()) {
2906  if (Diagnose) {
2907  Diag(StartLoc, diag::err_deleted_function_use);
2908  NoteDeletedFunction(Operator);
2909  }
2910  return true;
2911  }
2912 
2913  if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(),
2914  Matches[0].Found, Diagnose) == AR_inaccessible)
2915  return true;
2916 
2917  return false;
2918  }
2919 
2920  // We found multiple suitable operators; complain about the ambiguity.
2921  // FIXME: The standard doesn't say to do this; it appears that the intent
2922  // is that this should never happen.
2923  if (!Matches.empty()) {
2924  if (Diagnose) {
2925  Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found)
2926  << Name << RD;
2927  for (auto &Match : Matches)
2928  Diag(Match.FD->getLocation(), diag::note_member_declared_here) << Name;
2929  }
2930  return true;
2931  }
2932 
2933  // We did find operator delete/operator delete[] declarations, but
2934  // none of them were suitable.
2935  if (!Found.empty()) {
2936  if (Diagnose) {
2937  Diag(StartLoc, diag::err_no_suitable_delete_member_function_found)
2938  << Name << RD;
2939 
2940  for (NamedDecl *D : Found)
2941  Diag(D->getUnderlyingDecl()->getLocation(),
2942  diag::note_member_declared_here) << Name;
2943  }
2944  return true;
2945  }
2946 
2947  Operator = nullptr;
2948  return false;
2949 }
2950 
2951 namespace {
2952 /// Checks whether delete-expression, and new-expression used for
2953 /// initializing deletee have the same array form.
2954 class MismatchingNewDeleteDetector {
2955 public:
2956  enum MismatchResult {
2957  /// Indicates that there is no mismatch or a mismatch cannot be proven.
2958  NoMismatch,
2959  /// Indicates that variable is initialized with mismatching form of \a new.
2960  VarInitMismatches,
2961  /// Indicates that member is initialized with mismatching form of \a new.
2962  MemberInitMismatches,
2963  /// Indicates that 1 or more constructors' definitions could not been
2964  /// analyzed, and they will be checked again at the end of translation unit.
2965  AnalyzeLater
2966  };
2967 
2968  /// \param EndOfTU True, if this is the final analysis at the end of
2969  /// translation unit. False, if this is the initial analysis at the point
2970  /// delete-expression was encountered.
2971  explicit MismatchingNewDeleteDetector(bool EndOfTU)
2972  : Field(nullptr), IsArrayForm(false), EndOfTU(EndOfTU),
2973  HasUndefinedConstructors(false) {}
2974 
2975  /// Checks whether pointee of a delete-expression is initialized with
2976  /// matching form of new-expression.
2977  ///
2978  /// If return value is \c VarInitMismatches or \c MemberInitMismatches at the
2979  /// point where delete-expression is encountered, then a warning will be
2980  /// issued immediately. If return value is \c AnalyzeLater at the point where
2981  /// delete-expression is seen, then member will be analyzed at the end of
2982  /// translation unit. \c AnalyzeLater is returned iff at least one constructor
2983  /// couldn't be analyzed. If at least one constructor initializes the member
2984  /// with matching type of new, the return value is \c NoMismatch.
2985  MismatchResult analyzeDeleteExpr(const CXXDeleteExpr *DE);
2986  /// Analyzes a class member.
2987  /// \param Field Class member to analyze.
2988  /// \param DeleteWasArrayForm Array form-ness of the delete-expression used
2989  /// for deleting the \p Field.
2990  MismatchResult analyzeField(FieldDecl *Field, bool DeleteWasArrayForm);
2991  FieldDecl *Field;
2992  /// List of mismatching new-expressions used for initialization of the pointee
2994  /// Indicates whether delete-expression was in array form.
2995  bool IsArrayForm;
2996 
2997 private:
2998  const bool EndOfTU;
2999  /// Indicates that there is at least one constructor without body.
3000  bool HasUndefinedConstructors;
3001  /// Returns \c CXXNewExpr from given initialization expression.
3002  /// \param E Expression used for initializing pointee in delete-expression.
3003  /// E can be a single-element \c InitListExpr consisting of new-expression.
3004  const CXXNewExpr *getNewExprFromInitListOrExpr(const Expr *E);
3005  /// Returns whether member is initialized with mismatching form of
3006  /// \c new either by the member initializer or in-class initialization.
3007  ///
3008  /// If bodies of all constructors are not visible at the end of translation
3009  /// unit or at least one constructor initializes member with the matching
3010  /// form of \c new, mismatch cannot be proven, and this function will return
3011  /// \c NoMismatch.
3012  MismatchResult analyzeMemberExpr(const MemberExpr *ME);
3013  /// Returns whether variable is initialized with mismatching form of
3014  /// \c new.
3015  ///
3016  /// If variable is initialized with matching form of \c new or variable is not
3017  /// initialized with a \c new expression, this function will return true.
3018  /// If variable is initialized with mismatching form of \c new, returns false.
3019  /// \param D Variable to analyze.
3020  bool hasMatchingVarInit(const DeclRefExpr *D);
3021  /// Checks whether the constructor initializes pointee with mismatching
3022  /// form of \c new.
3023  ///
3024  /// Returns true, if member is initialized with matching form of \c new in
3025  /// member initializer list. Returns false, if member is initialized with the
3026  /// matching form of \c new in this constructor's initializer or given
3027  /// constructor isn't defined at the point where delete-expression is seen, or
3028  /// member isn't initialized by the constructor.
3029  bool hasMatchingNewInCtor(const CXXConstructorDecl *CD);
3030  /// Checks whether member is initialized with matching form of
3031  /// \c new in member initializer list.
3032  bool hasMatchingNewInCtorInit(const CXXCtorInitializer *CI);
3033  /// Checks whether member is initialized with mismatching form of \c new by
3034  /// in-class initializer.
3035  MismatchResult analyzeInClassInitializer();
3036 };
3037 }
3038 
3039 MismatchingNewDeleteDetector::MismatchResult
3040 MismatchingNewDeleteDetector::analyzeDeleteExpr(const CXXDeleteExpr *DE) {
3041  NewExprs.clear();
3042  assert(DE && "Expected delete-expression");
3043  IsArrayForm = DE->isArrayForm();
3044  const Expr *E = DE->getArgument()->IgnoreParenImpCasts();
3045  if (const MemberExpr *ME = dyn_cast<const MemberExpr>(E)) {
3046  return analyzeMemberExpr(ME);
3047  } else if (const DeclRefExpr *D = dyn_cast<const DeclRefExpr>(E)) {
3048  if (!hasMatchingVarInit(D))
3049  return VarInitMismatches;
3050  }
3051  return NoMismatch;
3052 }
3053 
3054 const CXXNewExpr *
3055 MismatchingNewDeleteDetector::getNewExprFromInitListOrExpr(const Expr *E) {
3056  assert(E != nullptr && "Expected a valid initializer expression");
3057  E = E->IgnoreParenImpCasts();
3058  if (const InitListExpr *ILE = dyn_cast<const InitListExpr>(E)) {
3059  if (ILE->getNumInits() == 1)
3060  E = dyn_cast<const CXXNewExpr>(ILE->getInit(0)->IgnoreParenImpCasts());
3061  }
3062 
3063  return dyn_cast_or_null<const CXXNewExpr>(E);
3064 }
3065 
3066 bool MismatchingNewDeleteDetector::hasMatchingNewInCtorInit(
3067  const CXXCtorInitializer *CI) {
3068  const CXXNewExpr *NE = nullptr;
3069  if (Field == CI->getMember() &&
3070  (NE = getNewExprFromInitListOrExpr(CI->getInit()))) {
3071  if (NE->isArray() == IsArrayForm)
3072  return true;
3073  else
3074  NewExprs.push_back(NE);
3075  }
3076  return false;
3077 }
3078 
3079 bool MismatchingNewDeleteDetector::hasMatchingNewInCtor(
3080  const CXXConstructorDecl *CD) {
3081  if (CD->isImplicit())
3082  return false;
3083  const FunctionDecl *Definition = CD;
3084  if (!CD->isThisDeclarationADefinition() && !CD->isDefined(Definition)) {
3085  HasUndefinedConstructors = true;
3086  return EndOfTU;
3087  }
3088  for (const auto *CI : cast<const CXXConstructorDecl>(Definition)->inits()) {
3089  if (hasMatchingNewInCtorInit(CI))
3090  return true;
3091  }
3092  return false;
3093 }
3094 
3095 MismatchingNewDeleteDetector::MismatchResult
3096 MismatchingNewDeleteDetector::analyzeInClassInitializer() {
3097  assert(Field != nullptr && "This should be called only for members");
3098  const Expr *InitExpr = Field->getInClassInitializer();
3099  if (!InitExpr)
3100  return EndOfTU ? NoMismatch : AnalyzeLater;
3101  if (const CXXNewExpr *NE = getNewExprFromInitListOrExpr(InitExpr)) {
3102  if (NE->isArray() != IsArrayForm) {
3103  NewExprs.push_back(NE);
3104  return MemberInitMismatches;
3105  }
3106  }
3107  return NoMismatch;
3108 }
3109 
3110 MismatchingNewDeleteDetector::MismatchResult
3111 MismatchingNewDeleteDetector::analyzeField(FieldDecl *Field,
3112  bool DeleteWasArrayForm) {
3113  assert(Field != nullptr && "Analysis requires a valid class member.");
3114  this->Field = Field;
3115  IsArrayForm = DeleteWasArrayForm;
3116  const CXXRecordDecl *RD = cast<const CXXRecordDecl>(Field->getParent());
3117  for (const auto *CD : RD->ctors()) {
3118  if (hasMatchingNewInCtor(CD))
3119  return NoMismatch;
3120  }
3121  if (HasUndefinedConstructors)
3122  return EndOfTU ? NoMismatch : AnalyzeLater;
3123  if (!NewExprs.empty())
3124  return MemberInitMismatches;
3125  return Field->hasInClassInitializer() ? analyzeInClassInitializer()
3126  : NoMismatch;
3127 }
3128 
3129 MismatchingNewDeleteDetector::MismatchResult
3130 MismatchingNewDeleteDetector::analyzeMemberExpr(const MemberExpr *ME) {
3131  assert(ME != nullptr && "Expected a member expression");
3132  if (FieldDecl *F = dyn_cast<FieldDecl>(ME->getMemberDecl()))
3133  return analyzeField(F, IsArrayForm);
3134  return NoMismatch;
3135 }
3136 
3137 bool MismatchingNewDeleteDetector::hasMatchingVarInit(const DeclRefExpr *D) {
3138  const CXXNewExpr *NE = nullptr;
3139  if (const VarDecl *VD = dyn_cast<const VarDecl>(D->getDecl())) {
3140  if (VD->hasInit() && (NE = getNewExprFromInitListOrExpr(VD->getInit())) &&
3141  NE->isArray() != IsArrayForm) {
3142  NewExprs.push_back(NE);
3143  }
3144  }
3145  return NewExprs.empty();
3146 }
3147 
3148 static void
3150  const MismatchingNewDeleteDetector &Detector) {
3151  SourceLocation EndOfDelete = SemaRef.getLocForEndOfToken(DeleteLoc);
3152  FixItHint H;
3153  if (!Detector.IsArrayForm)
3154  H = FixItHint::CreateInsertion(EndOfDelete, "[]");
3155  else {
3157  DeleteLoc, tok::l_square, SemaRef.getSourceManager(),
3158  SemaRef.getLangOpts(), true);
3159  if (RSquare.isValid())
3160  H = FixItHint::CreateRemoval(SourceRange(EndOfDelete, RSquare));
3161  }
3162  SemaRef.Diag(DeleteLoc, diag::warn_mismatched_delete_new)
3163  << Detector.IsArrayForm << H;
3164 
3165  for (const auto *NE : Detector.NewExprs)
3166  SemaRef.Diag(NE->getExprLoc(), diag::note_allocated_here)
3167  << Detector.IsArrayForm;
3168 }
3169 
3170 void Sema::AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE) {
3171  if (Diags.isIgnored(diag::warn_mismatched_delete_new, SourceLocation()))
3172  return;
3173  MismatchingNewDeleteDetector Detector(/*EndOfTU=*/false);
3174  switch (Detector.analyzeDeleteExpr(DE)) {
3175  case MismatchingNewDeleteDetector::VarInitMismatches:
3176  case MismatchingNewDeleteDetector::MemberInitMismatches: {
3177  DiagnoseMismatchedNewDelete(*this, DE->getBeginLoc(), Detector);
3178  break;
3179  }
3180  case MismatchingNewDeleteDetector::AnalyzeLater: {
3181  DeleteExprs[Detector.Field].push_back(
3182  std::make_pair(DE->getBeginLoc(), DE->isArrayForm()));
3183  break;
3184  }
3185  case MismatchingNewDeleteDetector::NoMismatch:
3186  break;
3187  }
3188 }
3189 
3190 void Sema::AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
3191  bool DeleteWasArrayForm) {
3192  MismatchingNewDeleteDetector Detector(/*EndOfTU=*/true);
3193  switch (Detector.analyzeField(Field, DeleteWasArrayForm)) {
3194  case MismatchingNewDeleteDetector::VarInitMismatches:
3195  llvm_unreachable("This analysis should have been done for class members.");
3196  case MismatchingNewDeleteDetector::AnalyzeLater:
3197  llvm_unreachable("Analysis cannot be postponed any point beyond end of "
3198  "translation unit.");
3199  case MismatchingNewDeleteDetector::MemberInitMismatches:
3200  DiagnoseMismatchedNewDelete(*this, DeleteLoc, Detector);
3201  break;
3202  case MismatchingNewDeleteDetector::NoMismatch:
3203  break;
3204  }
3205 }
3206 
3207 /// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in:
3208 /// @code ::delete ptr; @endcode
3209 /// or
3210 /// @code delete [] ptr; @endcode
3211 ExprResult
3212 Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
3213  bool ArrayForm, Expr *ExE) {
3214  // C++ [expr.delete]p1:
3215  // The operand shall have a pointer type, or a class type having a single
3216  // non-explicit conversion function to a pointer type. The result has type
3217  // void.
3218  //
3219  // DR599 amends "pointer type" to "pointer to object type" in both cases.
3220 
3221  ExprResult Ex = ExE;
3222  FunctionDecl *OperatorDelete = nullptr;
3223  bool ArrayFormAsWritten = ArrayForm;
3224  bool UsualArrayDeleteWantsSize = false;
3225 
3226  if (!Ex.get()->isTypeDependent()) {
3227  // Perform lvalue-to-rvalue cast, if needed.
3228  Ex = DefaultLvalueConversion(Ex.get());
3229  if (Ex.isInvalid())
3230  return ExprError();
3231 
3232  QualType Type = Ex.get()->getType();
3233 
3234  class DeleteConverter : public ContextualImplicitConverter {
3235  public:
3236  DeleteConverter() : ContextualImplicitConverter(false, true) {}
3237 
3238  bool match(QualType ConvType) override {
3239  // FIXME: If we have an operator T* and an operator void*, we must pick
3240  // the operator T*.
3241  if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
3242  if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType())
3243  return true;
3244  return false;
3245  }
3246 
3247  SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
3248  QualType T) override {
3249  return S.Diag(Loc, diag::err_delete_operand) << T;
3250  }
3251 
3252  SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
3253  QualType T) override {
3254  return S.Diag(Loc, diag::err_delete_incomplete_class_type) << T;
3255  }
3256 
3257  SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
3258  QualType T,
3259  QualType ConvTy) override {
3260  return S.Diag(Loc, diag::err_delete_explicit_conversion) << T << ConvTy;
3261  }
3262 
3263  SemaDiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
3264  QualType ConvTy) override {
3265  return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3266  << ConvTy;
3267  }
3268 
3269  SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
3270  QualType T) override {
3271  return S.Diag(Loc, diag::err_ambiguous_delete_operand) << T;
3272  }
3273 
3274  SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
3275  QualType ConvTy) override {
3276  return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3277  << ConvTy;
3278  }
3279 
3280  SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
3281  QualType T,
3282  QualType ConvTy) override {
3283  llvm_unreachable("conversion functions are permitted");
3284  }
3285  } Converter;
3286 
3287  Ex = PerformContextualImplicitConversion(StartLoc, Ex.get(), Converter);
3288  if (Ex.isInvalid())
3289  return ExprError();
3290  Type = Ex.get()->getType();
3291  if (!Converter.match(Type))
3292  // FIXME: PerformContextualImplicitConversion should return ExprError
3293  // itself in this case.
3294  return ExprError();
3295 
3296  QualType Pointee = Type->getAs<PointerType>()->getPointeeType();
3297  QualType PointeeElem = Context.getBaseElementType(Pointee);
3298 
3299  if (Pointee.getAddressSpace() != LangAS::Default &&
3300  !getLangOpts().OpenCLCPlusPlus)
3301  return Diag(Ex.get()->getBeginLoc(),
3302  diag::err_address_space_qualified_delete)
3303  << Pointee.getUnqualifiedType()
3305 
3306  CXXRecordDecl *PointeeRD = nullptr;
3307  if (Pointee->isVoidType() && !isSFINAEContext()) {
3308  // The C++ standard bans deleting a pointer to a non-object type, which
3309  // effectively bans deletion of "void*". However, most compilers support
3310  // this, so we treat it as a warning unless we're in a SFINAE context.
3311  Diag(StartLoc, diag::ext_delete_void_ptr_operand)
3312  << Type << Ex.get()->getSourceRange();
3313  } else if (Pointee->isFunctionType() || Pointee->isVoidType()) {
3314  return ExprError(Diag(StartLoc, diag::err_delete_operand)
3315  << Type << Ex.get()->getSourceRange());
3316  } else if (!Pointee->isDependentType()) {
3317  // FIXME: This can result in errors if the definition was imported from a
3318  // module but is hidden.
3319  if (!RequireCompleteType(StartLoc, Pointee,
3320  diag::warn_delete_incomplete, Ex.get())) {
3321  if (const RecordType *RT = PointeeElem->getAs<RecordType>())
3322  PointeeRD = cast<CXXRecordDecl>(RT->getDecl());
3323  }
3324  }
3325 
3326  if (Pointee->isArrayType() && !ArrayForm) {
3327  Diag(StartLoc, diag::warn_delete_array_type)
3328  << Type << Ex.get()->getSourceRange()
3329  << FixItHint::CreateInsertion(getLocForEndOfToken(StartLoc), "[]");
3330  ArrayForm = true;
3331  }
3332 
3334  ArrayForm ? OO_Array_Delete : OO_Delete);
3335 
3336  if (PointeeRD) {
3337  if (!UseGlobal &&
3338  FindDeallocationFunction(StartLoc, PointeeRD, DeleteName,
3339  OperatorDelete))
3340  return ExprError();
3341 
3342  // If we're allocating an array of records, check whether the
3343  // usual operator delete[] has a size_t parameter.
3344  if (ArrayForm) {
3345  // If the user specifically asked to use the global allocator,
3346  // we'll need to do the lookup into the class.
3347  if (UseGlobal)
3348  UsualArrayDeleteWantsSize =
3349  doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem);
3350 
3351  // Otherwise, the usual operator delete[] should be the
3352  // function we just found.
3353  else if (OperatorDelete && isa<CXXMethodDecl>(OperatorDelete))
3354  UsualArrayDeleteWantsSize =
3355  UsualDeallocFnInfo(*this,
3356  DeclAccessPair::make(OperatorDelete, AS_public))
3357  .HasSizeT;
3358  }
3359 
3360  if (!PointeeRD->hasIrrelevantDestructor())
3361  if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3362  MarkFunctionReferenced(StartLoc,
3363  const_cast<CXXDestructorDecl*>(Dtor));
3364  if (DiagnoseUseOfDecl(Dtor, StartLoc))
3365  return ExprError();
3366  }
3367 
3368  CheckVirtualDtorCall(PointeeRD->getDestructor(), StartLoc,
3369  /*IsDelete=*/true, /*CallCanBeVirtual=*/true,
3370  /*WarnOnNonAbstractTypes=*/!ArrayForm,
3371  SourceLocation());
3372  }
3373 
3374  if (!OperatorDelete) {
3375  if (getLangOpts().OpenCLCPlusPlus) {
3376  Diag(StartLoc, diag::err_openclcxx_not_supported) << "default delete";
3377  return ExprError();
3378  }
3379 
3380  bool IsComplete = isCompleteType(StartLoc, Pointee);
3381  bool CanProvideSize =
3382  IsComplete && (!ArrayForm || UsualArrayDeleteWantsSize ||
3383  Pointee.isDestructedType());
3384  bool Overaligned = hasNewExtendedAlignment(*this, Pointee);
3385 
3386  // Look for a global declaration.
3387  OperatorDelete = FindUsualDeallocationFunction(StartLoc, CanProvideSize,
3388  Overaligned, DeleteName);
3389  }
3390 
3391  MarkFunctionReferenced(StartLoc, OperatorDelete);
3392 
3393  // Check access and ambiguity of destructor if we're going to call it.
3394  // Note that this is required even for a virtual delete.
3395  bool IsVirtualDelete = false;
3396  if (PointeeRD) {
3397  if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3398  CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor,
3399  PDiag(diag::err_access_dtor) << PointeeElem);
3400  IsVirtualDelete = Dtor->isVirtual();
3401  }
3402  }
3403 
3404  DiagnoseUseOfDecl(OperatorDelete, StartLoc);
3405 
3406  // Convert the operand to the type of the first parameter of operator
3407  // delete. This is only necessary if we selected a destroying operator
3408  // delete that we are going to call (non-virtually); converting to void*
3409  // is trivial and left to AST consumers to handle.
3410  QualType ParamType = OperatorDelete->getParamDecl(0)->getType();
3411  if (!IsVirtualDelete && !ParamType->getPointeeType()->isVoidType()) {
3412  Qualifiers Qs = Pointee.getQualifiers();
3413  if (Qs.hasCVRQualifiers()) {
3414  // Qualifiers are irrelevant to this conversion; we're only looking
3415  // for access and ambiguity.
3416  Qs.removeCVRQualifiers();
3417  QualType Unqual = Context.getPointerType(
3419  Ex = ImpCastExprToType(Ex.get(), Unqual, CK_NoOp);
3420  }
3421  Ex = PerformImplicitConversion(Ex.get(), ParamType, AA_Passing);
3422  if (Ex.isInvalid())
3423  return ExprError();
3424  }
3425  }
3426 
3428  Context.VoidTy, UseGlobal, ArrayForm, ArrayFormAsWritten,
3429  UsualArrayDeleteWantsSize, OperatorDelete, Ex.get(), StartLoc);
3430  AnalyzeDeleteExprMismatch(Result);
3431  return Result;
3432 }
3433 
3435  bool IsDelete,
3436  FunctionDecl *&Operator) {
3437 
3439  IsDelete ? OO_Delete : OO_New);
3440 
3441  LookupResult R(S, NewName, TheCall->getBeginLoc(), Sema::LookupOrdinaryName);
3443  assert(!R.empty() && "implicitly declared allocation functions not found");
3444  assert(!R.isAmbiguous() && "global allocation functions are ambiguous");
3445 
3446  // We do our own custom access checks below.
3447  R.suppressDiagnostics();
3448 
3449  SmallVector<Expr *, 8> Args(TheCall->arg_begin(), TheCall->arg_end());
3450  OverloadCandidateSet Candidates(R.getNameLoc(),
3452  for (LookupResult::iterator FnOvl = R.begin(), FnOvlEnd = R.end();
3453  FnOvl != FnOvlEnd; ++FnOvl) {
3454  // Even member operator new/delete are implicitly treated as
3455  // static, so don't use AddMemberCandidate.
3456  NamedDecl *D = (*FnOvl)->getUnderlyingDecl();
3457 
3458  if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
3459  S.AddTemplateOverloadCandidate(FnTemplate, FnOvl.getPair(),
3460  /*ExplicitTemplateArgs=*/nullptr, Args,
3461  Candidates,
3462  /*SuppressUserConversions=*/false);
3463  continue;
3464  }
3465 
3466  FunctionDecl *Fn = cast<FunctionDecl>(D);
3467  S.AddOverloadCandidate(Fn, FnOvl.getPair(), Args, Candidates,
3468  /*SuppressUserConversions=*/false);
3469  }
3470 
3471  SourceRange Range = TheCall->getSourceRange();
3472 
3473  // Do the resolution.
3475  switch (Candidates.BestViableFunction(S, R.getNameLoc(), Best)) {
3476  case OR_Success: {
3477  // Got one!
3478  FunctionDecl *FnDecl = Best->Function;
3479  assert(R.getNamingClass() == nullptr &&
3480  "class members should not be considered");
3481 
3482  if (!FnDecl->isReplaceableGlobalAllocationFunction()) {
3483  S.Diag(R.getNameLoc(), diag::err_builtin_operator_new_delete_not_usual)
3484  << (IsDelete ? 1 : 0) << Range;
3485  S.Diag(FnDecl->getLocation(), diag::note_non_usual_function_declared_here)
3486  << R.getLookupName() << FnDecl->getSourceRange();
3487  return true;
3488  }
3489 
3490  Operator = FnDecl;
3491  return false;
3492  }
3493 
3494  case OR_No_Viable_Function:
3495  Candidates.NoteCandidates(
3496  PartialDiagnosticAt(R.getNameLoc(),
3497  S.PDiag(diag::err_ovl_no_viable_function_in_call)
3498  << R.getLookupName() << Range),
3499  S, OCD_AllCandidates, Args);
3500  return true;
3501 
3502  case OR_Ambiguous:
3503  Candidates.NoteCandidates(
3504  PartialDiagnosticAt(R.getNameLoc(),
3505  S.PDiag(diag::err_ovl_ambiguous_call)
3506  << R.getLookupName() << Range),
3507  S, OCD_ViableCandidates, Args);
3508  return true;
3509 
3510  case OR_Deleted: {
3511  Candidates.NoteCandidates(
3512  PartialDiagnosticAt(R.getNameLoc(), S.PDiag(diag::err_ovl_deleted_call)
3513  << R.getLookupName() << Range),
3514  S, OCD_AllCandidates, Args);
3515  return true;
3516  }
3517  }
3518  llvm_unreachable("Unreachable, bad result from BestViableFunction");
3519 }
3520 
3521 ExprResult
3522 Sema::SemaBuiltinOperatorNewDeleteOverloaded(ExprResult TheCallResult,
3523  bool IsDelete) {
3524  CallExpr *TheCall = cast<CallExpr>(TheCallResult.get());
3525  if (!getLangOpts().CPlusPlus) {
3526  Diag(TheCall->getExprLoc(), diag::err_builtin_requires_language)
3527  << (IsDelete ? "__builtin_operator_delete" : "__builtin_operator_new")
3528  << "C++";
3529  return ExprError();
3530  }
3531  // CodeGen assumes it can find the global new and delete to call,
3532  // so ensure that they are declared.
3534 
3535  FunctionDecl *OperatorNewOrDelete = nullptr;
3536  if (resolveBuiltinNewDeleteOverload(*this, TheCall, IsDelete,
3537  OperatorNewOrDelete))
3538  return ExprError();
3539  assert(OperatorNewOrDelete && "should be found");
3540 
3541  DiagnoseUseOfDecl(OperatorNewOrDelete, TheCall->getExprLoc());
3542  MarkFunctionReferenced(TheCall->getExprLoc(), OperatorNewOrDelete);
3543 
3544  TheCall->setType(OperatorNewOrDelete->getReturnType());
3545  for (unsigned i = 0; i != TheCall->getNumArgs(); ++i) {
3546  QualType ParamTy = OperatorNewOrDelete->getParamDecl(i)->getType();
3547  InitializedEntity Entity =
3550  Entity, TheCall->getArg(i)->getBeginLoc(), TheCall->getArg(i));
3551  if (Arg.isInvalid())
3552  return ExprError();
3553  TheCall->setArg(i, Arg.get());
3554  }
3555  auto Callee = dyn_cast<ImplicitCastExpr>(TheCall->getCallee());
3556  assert(Callee && Callee->getCastKind() == CK_BuiltinFnToFnPtr &&
3557  "Callee expected to be implicit cast to a builtin function pointer");
3558  Callee->setType(OperatorNewOrDelete->getType());
3559 
3560  return TheCallResult;
3561 }
3562 
3564  bool IsDelete, bool CallCanBeVirtual,
3565  bool WarnOnNonAbstractTypes,
3566  SourceLocation DtorLoc) {
3567  if (!dtor || dtor->isVirtual() || !CallCanBeVirtual || isUnevaluatedContext())
3568  return;
3569 
3570  // C++ [expr.delete]p3:
3571  // In the first alternative (delete object), if the static type of the
3572  // object to be deleted is different from its dynamic type, the static
3573  // type shall be a base class of the dynamic type of the object to be
3574  // deleted and the static type shall have a virtual destructor or the
3575  // behavior is undefined.
3576  //
3577  const CXXRecordDecl *PointeeRD = dtor->getParent();
3578  // Note: a final class cannot be derived from, no issue there
3579  if (!PointeeRD->isPolymorphic() || PointeeRD->hasAttr<FinalAttr>())
3580  return;
3581 
3582  // If the superclass is in a system header, there's nothing that can be done.
3583  // The `delete` (where we emit the warning) can be in a system header,
3584  // what matters for this warning is where the deleted type is defined.
3585  if (getSourceManager().isInSystemHeader(PointeeRD->getLocation()))
3586  return;
3587 
3588  QualType ClassType = dtor->getThisType()->getPointeeType();
3589  if (PointeeRD->isAbstract()) {
3590  // If the class is abstract, we warn by default, because we're
3591  // sure the code has undefined behavior.
3592  Diag(Loc, diag::warn_delete_abstract_non_virtual_dtor) << (IsDelete ? 0 : 1)
3593  << ClassType;
3594  } else if (WarnOnNonAbstractTypes) {
3595  // Otherwise, if this is not an array delete, it's a bit suspect,
3596  // but not necessarily wrong.
3597  Diag(Loc, diag::warn_delete_non_virtual_dtor) << (IsDelete ? 0 : 1)
3598  << ClassType;
3599  }
3600  if (!IsDelete) {
3601  std::string TypeStr;
3602  ClassType.getAsStringInternal(TypeStr, getPrintingPolicy());
3603  Diag(DtorLoc, diag::note_delete_non_virtual)
3604  << FixItHint::CreateInsertion(DtorLoc, TypeStr + "::");
3605  }
3606 }
3607 
3609  SourceLocation StmtLoc,
3610  ConditionKind CK) {
3611  ExprResult E =
3612  CheckConditionVariable(cast<VarDecl>(ConditionVar), StmtLoc, CK);
3613  if (E.isInvalid())
3614  return ConditionError();
3615  return ConditionResult(*this, ConditionVar, MakeFullExpr(E.get(), StmtLoc),
3617 }
3618 
3619 /// Check the use of the given variable as a C++ condition in an if,
3620 /// while, do-while, or switch statement.
3622  SourceLocation StmtLoc,
3623  ConditionKind CK) {
3624  if (ConditionVar->isInvalidDecl())
3625  return ExprError();
3626 
3627  QualType T = ConditionVar->getType();
3628 
3629  // C++ [stmt.select]p2:
3630  // The declarator shall not specify a function or an array.
3631  if (T->isFunctionType())
3632  return ExprError(Diag(ConditionVar->getLocation(),
3633  diag::err_invalid_use_of_function_type)
3634  << ConditionVar->getSourceRange());
3635  else if (T->isArrayType())
3636  return ExprError(Diag(ConditionVar->getLocation(),
3637  diag::err_invalid_use_of_array_type)
3638  << ConditionVar->getSourceRange());
3639 
3640  ExprResult Condition = BuildDeclRefExpr(
3641  ConditionVar, ConditionVar->getType().getNonReferenceType(), VK_LValue,
3642  ConditionVar->getLocation());
3643 
3644  switch (CK) {
3646  return CheckBooleanCondition(StmtLoc, Condition.get());
3647 
3649  return CheckBooleanCondition(StmtLoc, Condition.get(), true);
3650 
3651  case ConditionKind::Switch:
3652  return CheckSwitchCondition(StmtLoc, Condition.get());
3653  }
3654 
3655  llvm_unreachable("unexpected condition kind");
3656 }
3657 
3658 /// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
3659 ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr, bool IsConstexpr) {
3660  // C++ 6.4p4:
3661  // The value of a condition that is an initialized declaration in a statement
3662  // other than a switch statement is the value of the declared variable
3663  // implicitly converted to type bool. If that conversion is ill-formed, the
3664  // program is ill-formed.
3665  // The value of a condition that is an expression is the value of the
3666  // expression, implicitly converted to bool.
3667  //
3668  // FIXME: Return this value to the caller so they don't need to recompute it.
3669  llvm::APSInt Value(/*BitWidth*/1);
3670  return (IsConstexpr && !CondExpr->isValueDependent())
3671  ? CheckConvertedConstantExpression(CondExpr, Context.BoolTy, Value,
3674 }
3675 
3676 /// Helper function to determine whether this is the (deprecated) C++
3677 /// conversion from a string literal to a pointer to non-const char or
3678 /// non-const wchar_t (for narrow and wide string literals,
3679 /// respectively).
3680 bool
3682  // Look inside the implicit cast, if it exists.
3683  if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From))
3684  From = Cast->getSubExpr();
3685 
3686  // A string literal (2.13.4) that is not a wide string literal can
3687  // be converted to an rvalue of type "pointer to char"; a wide
3688  // string literal can be converted to an rvalue of type "pointer
3689  // to wchar_t" (C++ 4.2p2).
3690  if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens()))
3691  if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
3692  if (const BuiltinType *ToPointeeType
3693  = ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
3694  // This conversion is considered only when there is an
3695  // explicit appropriate pointer target type (C++ 4.2p2).
3696  if (!ToPtrType->getPointeeType().hasQualifiers()) {
3697  switch (StrLit->getKind()) {
3698  case StringLiteral::UTF8:
3699  case StringLiteral::UTF16:
3700  case StringLiteral::UTF32:
3701  // We don't allow UTF literals to be implicitly converted
3702  break;
3703  case StringLiteral::Ascii:
3704  return (ToPointeeType->getKind() == BuiltinType::Char_U ||
3705  ToPointeeType->getKind() == BuiltinType::Char_S);
3706  case StringLiteral::Wide:
3708  QualType(ToPointeeType, 0));
3709  }
3710  }
3711  }
3712 
3713  return false;
3714 }
3715 
3717  SourceLocation CastLoc,
3718  QualType Ty,
3719  CastKind Kind,
3720  CXXMethodDecl *Method,
3721  DeclAccessPair FoundDecl,
3722  bool HadMultipleCandidates,
3723  Expr *From) {
3724  switch (Kind) {
3725  default: llvm_unreachable("Unhandled cast kind!");
3726  case CK_ConstructorConversion: {
3727  CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method);
3728  SmallVector<Expr*, 8> ConstructorArgs;
3729 
3730  if (S.RequireNonAbstractType(CastLoc, Ty,
3731  diag::err_allocation_of_abstract_type))
3732  return ExprError();
3733 
3734  if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs))
3735  return ExprError();
3736 
3737  S.CheckConstructorAccess(CastLoc, Constructor, FoundDecl,
3739  if (S.DiagnoseUseOfDecl(Method, CastLoc))
3740  return ExprError();
3741 
3743  CastLoc, Ty, FoundDecl, cast<CXXConstructorDecl>(Method),
3744  ConstructorArgs, HadMultipleCandidates,
3745  /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3747  if (Result.isInvalid())
3748  return ExprError();
3749 
3750  return S.MaybeBindToTemporary(Result.getAs<Expr>());
3751  }
3752 
3753  case CK_UserDefinedConversion: {
3754  assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
3755 
3756  S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ nullptr, FoundDecl);
3757  if (S.DiagnoseUseOfDecl(Method, CastLoc))
3758  return ExprError();
3759 
3760  // Create an implicit call expr that calls it.
3761  CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method);
3762  ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv,
3763  HadMultipleCandidates);
3764  if (Result.isInvalid())
3765  return ExprError();
3766  // Record usage of conversion in an implicit cast.
3767  Result = ImplicitCastExpr::Create(S.Context, Result.get()->getType(),
3768  CK_UserDefinedConversion, Result.get(),
3769  nullptr, Result.get()->getValueKind());
3770 
3771  return S.MaybeBindToTemporary(Result.get());
3772  }
3773  }
3774 }
3775 
3776 /// PerformImplicitConversion - Perform an implicit conversion of the
3777 /// expression From to the type ToType using the pre-computed implicit
3778 /// conversion sequence ICS. Returns the converted
3779 /// expression. Action is the kind of conversion we're performing,
3780 /// used in the error message.
3781 ExprResult
3783  const ImplicitConversionSequence &ICS,
3784  AssignmentAction Action,
3785  CheckedConversionKind CCK) {
3786  // C++ [over.match.oper]p7: [...] operands of class type are converted [...]
3787  if (CCK == CCK_ForBuiltinOverloadedOp && !From->getType()->isRecordType())
3788  return From;
3789 
3790  switch (ICS.getKind()) {
3792  ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard,
3793  Action, CCK);
3794  if (Res.isInvalid())
3795  return ExprError();
3796  From = Res.get();
3797  break;
3798  }
3799 
3801 
3804  QualType BeforeToType;
3805  assert(FD && "no conversion function for user-defined conversion seq");
3806  if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) {
3807  CastKind = CK_UserDefinedConversion;
3808 
3809  // If the user-defined conversion is specified by a conversion function,
3810  // the initial standard conversion sequence converts the source type to
3811  // the implicit object parameter of the conversion function.
3812  BeforeToType = Context.getTagDeclType(Conv->getParent());
3813  } else {
3814  const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD);
3815  CastKind = CK_ConstructorConversion;
3816  // Do no conversion if dealing with ... for the first conversion.
3817  if (!ICS.UserDefined.EllipsisConversion) {
3818  // If the user-defined conversion is specified by a constructor, the
3819  // initial standard conversion sequence converts the source type to
3820  // the type required by the argument of the constructor
3821  BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType();
3822  }
3823  }
3824  // Watch out for ellipsis conversion.
3825  if (!ICS.UserDefined.EllipsisConversion) {
3826  ExprResult Res =
3827  PerformImplicitConversion(From, BeforeToType,
3829  CCK);
3830  if (Res.isInvalid())
3831  return ExprError();
3832  From = Res.get();
3833  }
3834 
3835  ExprResult CastArg = BuildCXXCastArgument(
3836  *this, From->getBeginLoc(), ToType.getNonReferenceType(), CastKind,
3837  cast<CXXMethodDecl>(FD), ICS.UserDefined.FoundConversionFunction,
3839 
3840  if (CastArg.isInvalid())
3841  return ExprError();
3842 
3843  From = CastArg.get();
3844 
3845  // C++ [over.match.oper]p7:
3846  // [...] the second standard conversion sequence of a user-defined
3847  // conversion sequence is not applied.
3848  if (CCK == CCK_ForBuiltinOverloadedOp)
3849  return From;
3850 
3851  return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
3852  AA_Converting, CCK);
3853  }
3854 
3856  ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(),
3857  PDiag(diag::err_typecheck_ambiguous_condition)
3858  << From->getSourceRange());
3859  return ExprError();
3860 
3862  llvm_unreachable("Cannot perform an ellipsis conversion");
3863 
3865  bool Diagnosed =
3867  From->getType(), From, Action);
3868  assert(Diagnosed && "failed to diagnose bad conversion"); (void)Diagnosed;
3869  return ExprError();
3870  }
3871 
3872  // Everything went well.
3873  return From;
3874 }
3875 
3876 /// PerformImplicitConversion - Perform an implicit conversion of the
3877 /// expression From to the type ToType by following the standard
3878 /// conversion sequence SCS. Returns the converted
3879 /// expression. Flavor is the context in which we're performing this
3880 /// conversion, for use in error messages.
3881 ExprResult
3883  const StandardConversionSequence& SCS,
3884  AssignmentAction Action,
3885  CheckedConversionKind CCK) {
3886  bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast);
3887 
3888  // Overall FIXME: we are recomputing too many types here and doing far too
3889  // much extra work. What this means is that we need to keep track of more
3890  // information that is computed when we try the implicit conversion initially,
3891  // so that we don't need to recompute anything here.
3892  QualType FromType = From->getType();
3893 
3894  if (SCS.CopyConstructor) {
3895  // FIXME: When can ToType be a reference type?
3896  assert(!ToType->isReferenceType());
3897  if (SCS.Second == ICK_Derived_To_Base) {
3898  SmallVector<Expr*, 8> ConstructorArgs;
3899  if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor),
3900  From, /*FIXME:ConstructLoc*/SourceLocation(),
3901  ConstructorArgs))
3902  return ExprError();
3903  return BuildCXXConstructExpr(
3904  /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
3906  ConstructorArgs, /*HadMultipleCandidates*/ false,
3907  /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3909  }
3910  return BuildCXXConstructExpr(
3911  /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
3913  From, /*HadMultipleCandidates*/ false,
3914  /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3916  }
3917 
3918  // Resolve overloaded function references.
3919  if (Context.hasSameType(FromType, Context.OverloadTy)) {
3920  DeclAccessPair Found;
3922  true, Found);
3923  if (!Fn)
3924  return ExprError();
3925 
3926  if (DiagnoseUseOfDecl(Fn, From->getBeginLoc()))
3927  return ExprError();
3928 
3929  From = FixOverloadedFunctionReference(From, Found, Fn);
3930  FromType = From->getType();
3931  }
3932 
3933  // If we're converting to an atomic type, first convert to the corresponding
3934  // non-atomic type.
3935  QualType ToAtomicType;
3936  if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) {
3937  ToAtomicType = ToType;
3938  ToType = ToAtomic->getValueType();
3939  }
3940 
3941  QualType InitialFromType = FromType;
3942  // Perform the first implicit conversion.
3943  switch (SCS.First) {
3944  case ICK_Identity:
3945  if (const AtomicType *FromAtomic = FromType->getAs<AtomicType>()) {
3946  FromType = FromAtomic->getValueType().getUnqualifiedType();
3947  From = ImplicitCastExpr::Create(Context, FromType, CK_AtomicToNonAtomic,
3948  From, /*BasePath=*/nullptr, VK_RValue);
3949  }
3950  break;
3951 
3952  case ICK_Lvalue_To_Rvalue: {
3953  assert(From->getObjectKind() != OK_ObjCProperty);
3954  ExprResult FromRes = DefaultLvalueConversion(From);
3955  assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!");
3956  From = FromRes.get();
3957  FromType = From->getType();
3958  break;
3959  }
3960 
3961  case ICK_Array_To_Pointer:
3962  FromType = Context.getArrayDecayedType(FromType);
3963  From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay,
3964  VK_RValue, /*BasePath=*/nullptr, CCK).get();
3965  break;
3966 
3968  FromType = Context.getPointerType(FromType);
3969  From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay,
3970  VK_RValue, /*BasePath=*/nullptr, CCK).get();
3971  break;
3972 
3973  default:
3974  llvm_unreachable("Improper first standard conversion");
3975  }
3976 
3977  // Perform the second implicit conversion
3978  switch (SCS.Second) {
3979  case ICK_Identity:
3980  // C++ [except.spec]p5:
3981  // [For] assignment to and initialization of pointers to functions,
3982  // pointers to member functions, and references to functions: the
3983  // target entity shall allow at least the exceptions allowed by the
3984  // source value in the assignment or initialization.
3985  switch (Action) {
3986  case AA_Assigning:
3987  case AA_Initializing:
3988  // Note, function argument passing and returning are initialization.
3989  case AA_Passing:
3990  case AA_Returning:
3991  case AA_Sending:
3992  case AA_Passing_CFAudited:
3993  if (CheckExceptionSpecCompatibility(From, ToType))
3994  return ExprError();
3995  break;
3996 
3997  case AA_Casting:
3998  case AA_Converting:
3999  // Casts and implicit conversions are not initialization, so are not
4000  // checked for exception specification mismatches.
4001  break;
4002  }
4003  // Nothing else to do.
4004  break;
4005 
4008  if (ToType->isBooleanType()) {
4009  assert(FromType->castAs<EnumType>()->getDecl()->isFixed() &&
4010  SCS.Second == ICK_Integral_Promotion &&
4011  "only enums with fixed underlying type can promote to bool");
4012  From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean,
4013  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4014  } else {
4015  From = ImpCastExprToType(From, ToType, CK_IntegralCast,
4016  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4017  }
4018  break;
4019 
4022  From = ImpCastExprToType(From, ToType, CK_FloatingCast,
4023  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4024  break;
4025 
4026  case ICK_Complex_Promotion:
4027  case ICK_Complex_Conversion: {
4028  QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType();
4029  QualType ToEl = ToType->getAs<ComplexType>()->getElementType();
4030  CastKind CK;
4031  if (FromEl->isRealFloatingType()) {
4032  if (ToEl->isRealFloatingType())
4033  CK = CK_FloatingComplexCast;
4034  else
4035  CK = CK_FloatingComplexToIntegralComplex;
4036  } else if (ToEl->isRealFloatingType()) {
4037  CK = CK_IntegralComplexToFloatingComplex;
4038  } else {
4039  CK = CK_IntegralComplexCast;
4040  }
4041  From = ImpCastExprToType(From, ToType, CK,
4042  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4043  break;
4044  }
4045 
4046  case ICK_Floating_Integral:
4047  if (ToType->isRealFloatingType())
4048  From = ImpCastExprToType(From, ToType, CK_IntegralToFloating,
4049  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4050  else
4051  From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral,
4052  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4053  break;
4054 
4056  From = ImpCastExprToType(From, ToType, CK_NoOp,
4057  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4058  break;
4059 
4061  case ICK_Pointer_Conversion: {
4062  if (SCS.IncompatibleObjC && Action != AA_Casting) {
4063  // Diagnose incompatible Objective-C conversions
4064  if (Action == AA_Initializing || Action == AA_Assigning)
4065  Diag(From->getBeginLoc(),
4066  diag::ext_typecheck_convert_incompatible_pointer)
4067  << ToType << From->getType() << Action << From->getSourceRange()
4068  << 0;
4069  else
4070  Diag(From->getBeginLoc(),
4071  diag::ext_typecheck_convert_incompatible_pointer)
4072  << From->getType() << ToType << Action << From->getSourceRange()
4073  << 0;
4074 
4075  if (From->getType()->isObjCObjectPointerType() &&
4076  ToType->isObjCObjectPointerType())
4080  From->getType())) {
4081  if (Action == AA_Initializing)
4082  Diag(From->getBeginLoc(), diag::err_arc_weak_unavailable_assign);
4083  else
4084  Diag(From->getBeginLoc(), diag::err_arc_convesion_of_weak_unavailable)
4085  << (Action == AA_Casting) << From->getType() << ToType
4086  << From->getSourceRange();
4087  }
4088 
4089  CastKind Kind;
4090  CXXCastPath BasePath;
4091  if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle))
4092  return ExprError();
4093 
4094  // Make sure we extend blocks if necessary.
4095  // FIXME: doing this here is really ugly.
4096  if (Kind == CK_BlockPointerToObjCPointerCast) {
4097  ExprResult E = From;
4099  From = E.get();
4100  }
4101  if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
4102  CheckObjCConversion(SourceRange(), ToType, From, CCK);
4103  From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
4104  .get();
4105  break;
4106  }
4107 
4108  case ICK_Pointer_Member: {
4109  CastKind Kind;
4110  CXXCastPath BasePath;
4111  if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle))
4112  return ExprError();
4113  if (CheckExceptionSpecCompatibility(From, ToType))
4114  return ExprError();
4115 
4116  // We may not have been able to figure out what this member pointer resolved
4117  // to up until this exact point. Attempt to lock-in it's inheritance model.
4119  (void)isCompleteType(From->getExprLoc(), From->getType());
4120  (void)isCompleteType(From->getExprLoc(), ToType);
4121  }
4122 
4123  From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
4124  .get();
4125  break;
4126  }
4127 
4129  // Perform half-to-boolean conversion via float.
4130  if (From->getType()->isHalfType()) {
4131  From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).get();
4132  FromType = Context.FloatTy;
4133  }
4134 
4135  From = ImpCastExprToType(From, Context.BoolTy,
4136  ScalarTypeToBooleanCastKind(FromType),
4137  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4138  break;
4139 
4140  case ICK_Derived_To_Base: {
4141  CXXCastPath BasePath;
4143  From->getType(), ToType.getNonReferenceType(), From->getBeginLoc(),
4144  From->getSourceRange(), &BasePath, CStyle))
4145  return ExprError();
4146 
4147  From = ImpCastExprToType(From, ToType.getNonReferenceType(),
4148  CK_DerivedToBase, From->getValueKind(),
4149  &BasePath, CCK).get();
4150  break;
4151  }
4152 
4153  case ICK_Vector_Conversion:
4154  From = ImpCastExprToType(From, ToType, CK_BitCast,
4155  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4156  break;
4157 
4158  case ICK_Vector_Splat: {
4159  // Vector splat from any arithmetic type to a vector.
4160  Expr *Elem = prepareVectorSplat(ToType, From).get();
4161  From = ImpCastExprToType(Elem, ToType, CK_VectorSplat, VK_RValue,
4162  /*BasePath=*/nullptr, CCK).get();
4163  break;
4164  }
4165 
4166  case ICK_Complex_Real:
4167  // Case 1. x -> _Complex y
4168  if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) {
4169  QualType ElType = ToComplex->getElementType();
4170  bool isFloatingComplex = ElType->isRealFloatingType();
4171 
4172  // x -> y
4173  if (Context.hasSameUnqualifiedType(ElType, From->getType())) {
4174  // do nothing
4175  } else if (From->getType()->isRealFloatingType()) {
4176  From = ImpCastExprToType(From, ElType,
4177  isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).get();
4178  } else {
4179  assert(From->getType()->isIntegerType());
4180  From = ImpCastExprToType(From, ElType,
4181  isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).get();
4182  }
4183  // y -> _Complex y
4184  From = ImpCastExprToType(From, ToType,
4185  isFloatingComplex ? CK_FloatingRealToComplex
4186  : CK_IntegralRealToComplex).get();
4187 
4188  // Case 2. _Complex x -> y
4189  } else {
4190  const ComplexType *FromComplex = From->getType()->getAs<ComplexType>();
4191  assert(FromComplex);
4192 
4193  QualType ElType = FromComplex->getElementType();
4194  bool isFloatingComplex = ElType->isRealFloatingType();
4195 
4196  // _Complex x -> x
4197  From = ImpCastExprToType(From, ElType,
4198  isFloatingComplex ? CK_FloatingComplexToReal
4199  : CK_IntegralComplexToReal,
4200  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4201 
4202  // x -> y
4203  if (Context.hasSameUnqualifiedType(ElType, ToType)) {
4204  // do nothing
4205  } else if (ToType->isRealFloatingType()) {
4206  From = ImpCastExprToType(From, ToType,
4207  isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating,
4208  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4209  } else {
4210  assert(ToType->isIntegerType());
4211  From = ImpCastExprToType(From, ToType,
4212  isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast,
4213  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4214  }
4215  }
4216  break;
4217 
4219  LangAS AddrSpaceL =
4220  ToType->castAs<BlockPointerType>()->getPointeeType().getAddressSpace();
4221  LangAS AddrSpaceR =
4222  FromType->castAs<BlockPointerType>()->getPointeeType().getAddressSpace();
4223  assert(Qualifiers::isAddressSpaceSupersetOf(AddrSpaceL, AddrSpaceR) &&
4224  "Invalid cast");
4225  CastKind Kind =
4226  AddrSpaceL != AddrSpaceR ? CK_AddressSpaceConversion : CK_BitCast;
4227  From = ImpCastExprToType(From, ToType.getUnqualifiedType(), Kind,
4228  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4229  break;
4230  }
4231 
4233  ExprResult FromRes = From;
4234  Sema::AssignConvertType ConvTy =
4236  if (FromRes.isInvalid())
4237  return ExprError();
4238  From = FromRes.get();
4239  assert ((ConvTy == Sema::Compatible) &&
4240  "Improper transparent union conversion");
4241  (void)ConvTy;
4242  break;
4243  }
4244 
4247  From = ImpCastExprToType(From, ToType,
4248  CK_ZeroToOCLOpaqueType,
4249  From->getValueKind()).get();
4250  break;
4251 
4252  case ICK_Lvalue_To_Rvalue:
4253  case ICK_Array_To_Pointer:
4256  case ICK_Qualification:
4258  case ICK_C_Only_Conversion:
4260  llvm_unreachable("Improper second standard conversion");
4261  }
4262 
4263  switch (SCS.Third) {
4264  case ICK_Identity:
4265  // Nothing to do.
4266  break;
4267 
4269  // If both sides are functions (or pointers/references to them), there could
4270  // be incompatible exception declarations.
4271  if (CheckExceptionSpecCompatibility(From, ToType))
4272  return ExprError();
4273 
4274  From = ImpCastExprToType(From, ToType, CK_NoOp,
4275  VK_RValue, /*BasePath=*/nullptr, CCK).get();
4276  break;
4277 
4278  case ICK_Qualification: {
4279  // The qualification keeps the category of the inner expression, unless the
4280  // target type isn't a reference.
4281  ExprValueKind VK =
4282  ToType->isReferenceType() ? From->getValueKind() : VK_RValue;
4283 
4284  CastKind CK = CK_NoOp;
4285 
4286  if (ToType->isReferenceType() &&
4287  ToType->getPointeeType().getAddressSpace() !=
4288  From->getType().getAddressSpace())
4289  CK = CK_AddressSpaceConversion;
4290 
4291  if (ToType->isPointerType() &&
4292  ToType->getPointeeType().getAddressSpace() !=
4293  From->getType()->getPointeeType().getAddressSpace())
4294  CK = CK_AddressSpaceConversion;
4295 
4296  From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context), CK, VK,
4297  /*BasePath=*/nullptr, CCK)
4298  .get();
4299 
4301  !getLangOpts().WritableStrings) {
4302  Diag(From->getBeginLoc(),
4303  getLangOpts().CPlusPlus11
4304  ? diag::ext_deprecated_string_literal_conversion
4305  : diag::warn_deprecated_string_literal_conversion)
4306  << ToType.getNonReferenceType();
4307  }
4308 
4309  break;
4310  }
4311 
4312  default:
4313  llvm_unreachable("Improper third standard conversion");
4314  }
4315 
4316  // If this conversion sequence involved a scalar -> atomic conversion, perform
4317  // that conversion now.
4318  if (!ToAtomicType.isNull()) {
4319  assert(Context.hasSameType(
4320  ToAtomicType->castAs<AtomicType>()->getValueType(), From->getType()));
4321  From = ImpCastExprToType(From, ToAtomicType, CK_NonAtomicToAtomic,
4322  VK_RValue, nullptr, CCK).get();
4323  }
4324 
4325  // If this conversion sequence succeeded and involved implicitly converting a
4326  // _Nullable type to a _Nonnull one, complain.
4327  if (!isCast(CCK))
4328  diagnoseNullableToNonnullConversion(ToType, InitialFromType,
4329  From->getBeginLoc());
4330 
4331  return From;
4332 }
4333 
4334 /// Check the completeness of a type in a unary type trait.
4335 ///
4336 /// If the particular type trait requires a complete type, tries to complete
4337 /// it. If completing the type fails, a diagnostic is emitted and false
4338 /// returned. If completing the type succeeds or no completion was required,
4339 /// returns true.
4341  SourceLocation Loc,
4342  QualType ArgTy) {
4343  // C++0x [meta.unary.prop]p3:
4344  // For all of the class templates X declared in this Clause, instantiating
4345  // that template with a template argument that is a class template
4346  // specialization may result in the implicit instantiation of the template
4347  // argument if and only if the semantics of X require that the argument
4348  // must be a complete type.
4349  // We apply this rule to all the type trait expressions used to implement
4350  // these class templates. We also try to follow any GCC documented behavior
4351  // in these expressions to ensure portability of standard libraries.
4352  switch (UTT) {
4353  default: llvm_unreachable("not a UTT");
4354  // is_complete_type somewhat obviously cannot require a complete type.
4355  case UTT_IsCompleteType:
4356  // Fall-through
4357 
4358  // These traits are modeled on the type predicates in C++0x
4359  // [meta.unary.cat] and [meta.unary.comp]. They are not specified as
4360  // requiring a complete type, as whether or not they return true cannot be
4361  // impacted by the completeness of the type.
4362  case UTT_IsVoid:
4363  case UTT_IsIntegral:
4364  case UTT_IsFloatingPoint:
4365  case UTT_IsArray:
4366  case UTT_IsPointer:
4367  case UTT_IsLvalueReference:
4368  case UTT_IsRvalueReference:
4371  case UTT_IsEnum:
4372  case UTT_IsUnion:
4373  case UTT_IsClass:
4374  case UTT_IsFunction:
4375  case UTT_IsReference:
4376  case UTT_IsArithmetic:
4377  case UTT_IsFundamental:
4378  case UTT_IsObject:
4379  case UTT_IsScalar:
4380  case UTT_IsCompound:
4381  case UTT_IsMemberPointer:
4382  // Fall-through
4383 
4384  // These traits are modeled on type predicates in C++0x [meta.unary.prop]
4385  // which requires some of its traits to have the complete type. However,
4386  // the completeness of the type cannot impact these traits' semantics, and
4387  // so they don't require it. This matches the comments on these traits in
4388  // Table 49.
4389  case UTT_IsConst:
4390  case UTT_IsVolatile:
4391  case UTT_IsSigned:
4392  case UTT_IsUnsigned:
4393 
4394  // This type trait always returns false, checking the type is moot.
4395  case UTT_IsInterfaceClass:
4396  return true;
4397 
4398  // C++14 [meta.unary.prop]:
4399  // If T is a non-union class type, T shall be a complete type.
4400  case UTT_IsEmpty:
4401  case UTT_IsPolymorphic:
4402  case UTT_IsAbstract:
4403  if (const auto *RD = ArgTy->getAsCXXRecordDecl())
4404  if (!RD->isUnion())
4405  return !S.RequireCompleteType(
4406  Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4407  return true;
4408 
4409  // C++14 [meta.unary.prop]:
4410  // If T is a class type, T shall be a complete type.
4411  case UTT_IsFinal:
4412  case UTT_IsSealed:
4413  if (ArgTy->getAsCXXRecordDecl())
4414  return !S.RequireCompleteType(
4415  Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4416  return true;
4417 
4418  // C++1z [meta.unary.prop]:
4419  // remove_all_extents_t<T> shall be a complete type or cv void.
4420  case UTT_IsAggregate:
4421  case UTT_IsTrivial:
4423  case UTT_IsStandardLayout:
4424  case UTT_IsPOD:
4425  case UTT_IsLiteral:
4426  // Per the GCC type traits documentation, T shall be a complete type, cv void,
4427  // or an array of unknown bound. But GCC actually imposes the same constraints
4428  // as above.
4429  case UTT_HasNothrowAssign:
4432  case UTT_HasNothrowCopy:
4433  case UTT_HasTrivialAssign:
4437  case UTT_HasTrivialCopy:
4440  ArgTy = QualType(ArgTy->getBaseElementTypeUnsafe(), 0);
4441  LLVM_FALLTHROUGH;
4442 
4443  // C++1z [meta.unary.prop]:
4444  // T shall be a complete type, cv void, or an array of unknown bound.
4445  case UTT_IsDestructible:
4449  if (ArgTy->isIncompleteArrayType() || ArgTy->isVoidType())
4450  return true;
4451 
4452  return !S.RequireCompleteType(
4453  Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4454  }
4455 }
4456 
4458  Sema &Self, SourceLocation KeyLoc, ASTContext &C,
4459  bool (CXXRecordDecl::*HasTrivial)() const,
4460  bool (CXXRecordDecl::*HasNonTrivial)() const,
4461  bool (CXXMethodDecl::*IsDesiredOp)() const)
4462 {
4463  CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
4464  if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)())
4465  return true;
4466 
4468  DeclarationNameInfo NameInfo(Name, KeyLoc);
4469  LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName);
4470  if (Self.LookupQualifiedName(Res, RD)) {
4471  bool FoundOperator = false;
4472  Res.suppressDiagnostics();
4473  for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end();
4474  Op != OpEnd; ++Op) {
4475  if (isa<FunctionTemplateDecl>(*Op))
4476  continue;
4477 
4478  CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op);
4479  if((Operator->*IsDesiredOp)()) {
4480  FoundOperator = true;
4481  const FunctionProtoType *CPT =
4482  Operator->getType()->getAs<FunctionProtoType>();
4483  CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4484  if (!CPT || !CPT->isNothrow())
4485  return false;
4486  }
4487  }
4488  return FoundOperator;
4489  }
4490  return false;
4491 }
4492 
4493 static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
4494  SourceLocation KeyLoc, QualType T) {
4495  assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
4496 
4497  ASTContext &C = Self.Context;
4498  switch(UTT) {
4499  default: llvm_unreachable("not a UTT");
4500  // Type trait expressions corresponding to the primary type category
4501  // predicates in C++0x [meta.unary.cat].
4502  case UTT_IsVoid:
4503  return T->isVoidType();
4504  case UTT_IsIntegral:
4505  return T->isIntegralType(C);
4506  case UTT_IsFloatingPoint:
4507  return T->isFloatingType();
4508  case UTT_IsArray:
4509  return T->isArrayType();
4510  case UTT_IsPointer:
4511  return T->isPointerType();
4512  case UTT_IsLvalueReference:
4513  return T->isLValueReferenceType();
4514  case UTT_IsRvalueReference:
4515  return T->isRValueReferenceType();
4517  return T->isMemberFunctionPointerType();
4519  return T->isMemberDataPointerType();
4520  case UTT_IsEnum:
4521  return T->isEnumeralType();
4522  case UTT_IsUnion:
4523  return T->isUnionType();
4524  case UTT_IsClass:
4525  return T->isClassType() || T->isStructureType() || T->isInterfaceType();
4526  case UTT_IsFunction:
4527  return T->isFunctionType();
4528 
4529  // Type trait expressions which correspond to the convenient composition
4530  // predicates in C++0x [meta.unary.comp].
4531  case UTT_IsReference:
4532  return T->isReferenceType();
4533  case UTT_IsArithmetic:
4534  return T->isArithmeticType() && !T->isEnumeralType();
4535  case UTT_IsFundamental:
4536  return T->isFundamentalType();
4537  case UTT_IsObject:
4538  return T->isObjectType();
4539  case UTT_IsScalar:
4540  // Note: semantic analysis depends on Objective-C lifetime types to be
4541  // considered scalar types. However, such types do not actually behave
4542  // like scalar types at run time (since they may require retain/release
4543  // operations), so we report them as non-scalar.
4544  if (T->isObjCLifetimeType()) {
4545  switch (T.getObjCLifetime()) {
4546  case Qualifiers::OCL_None:
4548  return true;
4549 
4551  case Qualifiers::OCL_Weak:
4553  return false;
4554  }
4555  }
4556 
4557  return T->isScalarType();
4558  case UTT_IsCompound:
4559  return T->isCompoundType();
4560  case UTT_IsMemberPointer:
4561  return T->isMemberPointerType();
4562 
4563  // Type trait expressions which correspond to the type property predicates
4564  // in C++0x [meta.unary.prop].
4565  case UTT_IsConst:
4566  return T.isConstQualified();
4567  case UTT_IsVolatile:
4568  return T.isVolatileQualified();
4569  case UTT_IsTrivial:
4570  return T.isTrivialType(C);
4572  return T.isTriviallyCopyableType(C);
4573  case UTT_IsStandardLayout:
4574  return T->isStandardLayoutType();
4575  case UTT_IsPOD:
4576  return T.isPODType(C);
4577  case UTT_IsLiteral:
4578  return T->isLiteralType(C);
4579  case UTT_IsEmpty:
4580  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4581  return !RD->isUnion() && RD->isEmpty();
4582  return false;
4583  case UTT_IsPolymorphic:
4584  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4585  return !RD->isUnion() && RD->isPolymorphic();
4586  return false;
4587  case UTT_IsAbstract:
4588  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4589  return !RD->isUnion() && RD->isAbstract();
4590  return false;
4591  case UTT_IsAggregate:
4592  // Report vector extensions and complex types as aggregates because they
4593  // support aggregate initialization. GCC mirrors this behavior for vectors
4594  // but not _Complex.
4595  return T->isAggregateType() || T->isVectorType() || T->isExtVectorType() ||
4596  T->isAnyComplexType();
4597  // __is_interface_class only returns true when CL is invoked in /CLR mode and
4598  // even then only when it is used with the 'interface struct ...' syntax
4599  // Clang doesn't support /CLR which makes this type trait moot.
4600  case UTT_IsInterfaceClass:
4601  return false;
4602  case UTT_IsFinal:
4603  case UTT_IsSealed:
4604  if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4605  return RD->hasAttr<FinalAttr>();
4606  return false;
4607  case UTT_IsSigned:
4608  return T->isSignedIntegerType();
4609  case UTT_IsUnsigned:
4610  return T->isUnsignedIntegerType();
4611 
4612  // Type trait expressions which query classes regarding their construction,
4613  // destruction, and copying. Rather than being based directly on the
4614  // related type predicates in the standard, they are specified by both
4615  // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those
4616  // specifications.
4617  //
4618  // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
4619  // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4620  //
4621  // Note that these builtins do not behave as documented in g++: if a class
4622  // has both a trivial and a non-trivial special member of a particular kind,
4623  // they return false! For now, we emulate this behavior.
4624  // FIXME: This appears to be a g++ bug: more complex cases reveal that it
4625  // does not correctly compute triviality in the presence of multiple special
4626  // members of the same kind. Revisit this once the g++ bug is fixed.
4628  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4629  // If __is_pod (type) is true then the trait is true, else if type is
4630  // a cv class or union type (or array thereof) with a trivial default
4631  // constructor ([class.ctor]) then the trait is true, else it is false.
4632  if (T.isPODType(C))
4633  return true;
4634  if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4635  return RD->hasTrivialDefaultConstructor() &&
4636  !RD->hasNonTrivialDefaultConstructor();
4637  return false;
4639  // This trait is implemented by MSVC 2012 and needed to parse the
4640  // standard library headers. Specifically this is used as the logic
4641  // behind std::is_trivially_move_constructible (20.9.4.3).
4642  if (T.isPODType(C))
4643  return true;
4644  if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4645  return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor();
4646  return false;
4647  case UTT_HasTrivialCopy:
4648  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4649  // If __is_pod (type) is true or type is a reference type then
4650  // the trait is true, else if type is a cv class or union type
4651  // with a trivial copy constructor ([class.copy]) then the trait
4652  // is true, else it is false.
4653  if (T.isPODType(C) || T->isReferenceType())
4654  return true;
4655  if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4656  return RD->hasTrivialCopyConstructor() &&
4657  !RD->hasNonTrivialCopyConstructor();
4658  return false;
4660  // This trait is implemented by MSVC 2012 and needed to parse the
4661  // standard library headers. Specifically it is used as the logic
4662  // behind std::is_trivially_move_assignable (20.9.4.3)
4663  if (T.isPODType(C))
4664  return true;
4665  if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4666  return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment();
4667  return false;
4668  case UTT_HasTrivialAssign:
4669  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4670  // If type is const qualified or is a reference type then the
4671  // trait is false. Otherwise if __is_pod (type) is true then the
4672  // trait is true, else if type is a cv class or union type with
4673  // a trivial copy assignment ([class.copy]) then the trait is
4674  // true, else it is false.
4675  // Note: the const and reference restrictions are interesting,
4676  // given that const and reference members don't prevent a class
4677  // from having a trivial copy assignment operator (but do cause
4678  // errors if the copy assignment operator is actually used, q.v.
4679  // [class.copy]p12).
4680 
4681  if (T.isConstQualified())
4682  return false;
4683  if (T.isPODType(C))
4684  return true;
4685  if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4686  return RD->hasTrivialCopyAssignment() &&
4687  !RD->hasNonTrivialCopyAssignment();
4688  return false;
4689  case UTT_IsDestructible:
4692  // C++14 [meta.unary.prop]:
4693  // For reference types, is_destructible<T>::value is true.
4694  if (T->isReferenceType())
4695  return true;
4696 
4697  // Objective-C++ ARC: autorelease types don't require destruction.
4698  if (T->isObjCLifetimeType() &&
4700  return true;
4701 
4702  // C++14 [meta.unary.prop]:
4703  // For incomplete types and function types, is_destructible<T>::value is
4704  // false.
4705  if (T->isIncompleteType() || T->isFunctionType())
4706  return false;
4707 
4708  // A type that requires destruction (via a non-trivial destructor or ARC
4709  // lifetime semantics) is not trivially-destructible.
4711  return false;
4712 
4713  // C++14 [meta.unary.prop]:
4714  // For object types and given U equal to remove_all_extents_t<T>, if the
4715  // expression std::declval<U&>().~U() is well-formed when treated as an
4716  // unevaluated operand (Clause 5), then is_destructible<T>::value is true
4717  if (auto *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
4718  CXXDestructorDecl *Destructor = Self.LookupDestructor(RD);
4719  if (!Destructor)
4720  return false;
4721  // C++14 [dcl.fct.def.delete]p2:
4722  // A program that refers to a deleted function implicitly or
4723  // explicitly, other than to declare it, is ill-formed.
4724  if (Destructor->isDeleted())
4725  return false;
4726  if (C.getLangOpts().AccessControl && Destructor->getAccess() != AS_public)
4727  return false;
4728  if (UTT == UTT_IsNothrowDestructible) {
4729  const FunctionProtoType *CPT =
4730  Destructor->getType()->getAs<FunctionProtoType>();
4731  CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4732  if (!CPT || !CPT->isNothrow())
4733  return false;
4734  }
4735  }
4736  return true;
4737 
4739  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
4740  // If __is_pod (type) is true or type is a reference type
4741  // then the trait is true, else if type is a cv class or union
4742  // type (or array thereof) with a trivial destructor
4743  // ([class.dtor]) then the trait is true, else it is
4744  // false.
4745  if (T.isPODType(C) || T->isReferenceType())
4746  return true;
4747 
4748  // Objective-C++ ARC: autorelease types don't require destruction.
4749  if (T->isObjCLifetimeType() &&
4751  return true;
4752 
4753  if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4754  return RD->hasTrivialDestructor();
4755  return false;
4756  // TODO: Propagate nothrowness for implicitly declared special members.
4757  case UTT_HasNothrowAssign:
4758  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4759  // If type is const qualified or is a reference type then the
4760  // trait is false. Otherwise if __has_trivial_assign (type)
4761  // is true then the trait is true, else if type is a cv class
4762  // or union type with copy assignment operators that are known
4763  // not to throw an exception then the trait is true, else it is
4764  // false.
4765  if (C.getBaseElementType(T).isConstQualified())
4766  return false;
4767  if (T->isReferenceType())
4768  return false;
4769  if (T.isPODType(C) || T->isObjCLifetimeType())
4770  return true;
4771 
4772  if (const RecordType *RT = T->getAs<RecordType>())
4773  return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
4777  return false;
4779  // This trait is implemented by MSVC 2012 and needed to parse the
4780  // standard library headers. Specifically this is used as the logic
4781  // behind std::is_nothrow_move_assignable (20.9.4.3).
4782  if (T.isPODType(C))
4783  return true;
4784 
4785  if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>())
4786  return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
4790  return false;
4791  case UTT_HasNothrowCopy:
4792  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4793  // If __has_trivial_copy (type) is true then the trait is true, else
4794  // if type is a cv class or union type with copy constructors that are
4795  // known not to throw an exception then the trait is true, else it is
4796  // false.
4797  if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
4798  return true;
4799  if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
4800  if (RD->hasTrivialCopyConstructor() &&
4801  !RD->hasNonTrivialCopyConstructor())
4802  return true;
4803 
4804  bool FoundConstructor = false;
4805  unsigned FoundTQs;
4806  for (const auto *ND : Self.LookupConstructors(RD)) {
4807  // A template constructor is never a copy constructor.
4808  // FIXME: However, it may actually be selected at the actual overload
4809  // resolution point.
4810  if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
4811  continue;
4812  // UsingDecl itself is not a constructor
4813  if (isa<UsingDecl>(ND))
4814  continue;
4815  auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
4816  if (Constructor->isCopyConstructor(FoundTQs)) {
4817  FoundConstructor = true;
4818  const FunctionProtoType *CPT
4819  = Constructor->getType()->getAs<FunctionProtoType>();
4820  CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4821  if (!CPT)
4822  return false;
4823  // TODO: check whether evaluating default arguments can throw.
4824  // For now, we'll be conservative and assume that they can throw.
4825  if (!CPT->isNothrow() || CPT->getNumParams() > 1)
4826  return false;
4827  }
4828  }
4829 
4830  return FoundConstructor;
4831  }
4832  return false;
4834  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
4835  // If __has_trivial_constructor (type) is true then the trait is
4836  // true, else if type is a cv class or union type (or array
4837  // thereof) with a default constructor that is known not to
4838  // throw an exception then the trait is true, else it is false.
4839  if (T.isPODType(C) || T->isObjCLifetimeType())
4840  return true;
4841  if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
4842  if (RD->hasTrivialDefaultConstructor() &&
4843  !RD->hasNonTrivialDefaultConstructor())
4844  return true;
4845 
4846  bool FoundConstructor = false;
4847  for (const auto *ND : Self.LookupConstructors(RD)) {
4848  // FIXME: In C++0x, a constructor template can be a default constructor.
4849  if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
4850  continue;
4851  // UsingDecl itself is not a constructor
4852  if (isa<UsingDecl>(ND))
4853  continue;
4854  auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
4855  if (Constructor->isDefaultConstructor()) {
4856  FoundConstructor = true;
4857  const FunctionProtoType *CPT
4858  = Constructor->getType()->getAs<FunctionProtoType>();
4859  CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4860  if (!CPT)
4861  return false;
4862  // FIXME: check whether evaluating default arguments can throw.
4863  // For now, we'll be conservative and assume that they can throw.
4864  if (!CPT->isNothrow() || CPT->getNumParams() > 0)
4865  return false;
4866  }
4867  }
4868  return FoundConstructor;
4869  }
4870  return false;
4872  // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4873  // If type is a class type with a virtual destructor ([class.dtor])
4874  // then the trait is true, else it is false.
4875  if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4876  if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
4877  return Destructor->isVirtual();
4878  return false;
4879 
4880  // These type trait expressions are modeled on the specifications for the
4881  // Embarcadero C++0x type trait functions:
4882  // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4883  case UTT_IsCompleteType:
4884  // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_):
4885  // Returns True if and only if T is a complete type at the point of the
4886  // function call.
4887  return !T->isIncompleteType();
4889  return C.hasUniqueObjectRepresentations(T);
4890  }
4891 }
4892 
4893 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
4894  QualType RhsT, SourceLocation KeyLoc);
4895 
4898  SourceLocation RParenLoc) {
4899  if (Kind <= UTT_Last)
4900  return EvaluateUnaryTypeTrait(S, Kind, KWLoc, Args[0]->getType());
4901 
4902  // Evaluate BTT_ReferenceBindsToTemporary alongside the IsConstructible
4903  // traits to avoid duplication.
4904  if (Kind <= BTT_Last && Kind != BTT_ReferenceBindsToTemporary)
4905  return EvaluateBinaryTypeTrait(S, Kind, Args[0]->getType(),
4906  Args[1]->getType(), RParenLoc);
4907 
4908  switch (Kind) {
4913  // C++11 [meta.unary.prop]:
4914  // is_trivially_constructible is defined as:
4915  //
4916  // is_constructible<T, Args...>::value is true and the variable
4917  // definition for is_constructible, as defined below, is known to call
4918  // no operation that is not trivial.
4919  //
4920  // The predicate condition for a template specialization
4921  // is_constructible<T, Args...> shall be satisfied if and only if the
4922  // following variable definition would be well-formed for some invented
4923  // variable t:
4924  //
4925  // T t(create<Args>()...);
4926  assert(!Args.empty());
4927 
4928  // Precondition: T and all types in the parameter pack Args shall be
4929  // complete types, (possibly cv-qualified) void, or arrays of
4930  // unknown bound.
4931  for (const auto *TSI : Args) {
4932  QualType ArgTy = TSI->getType();
4933  if (ArgTy->isVoidType() || ArgTy->isIncompleteArrayType())
4934  continue;
4935 
4936  if (S.RequireCompleteType(KWLoc, ArgTy,
4937  diag::err_incomplete_type_used_in_type_trait_expr))
4938  return false;
4939  }
4940 
4941  // Make sure the first argument is not incomplete nor a function type.
4942  QualType T = Args[0]->getType();
4943  if (T->isIncompleteType() || T->isFunctionType())
4944  return false;
4945 
4946  // Make sure the first argument is not an abstract type.
4947  CXXRecordDecl *RD = T->getAsCXXRecordDecl();
4948  if (RD && RD->isAbstract())
4949  return false;
4950 
4951  SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs;
4952  SmallVector<Expr *, 2> ArgExprs;
4953  ArgExprs.reserve(Args.size() - 1);
4954  for (unsigned I = 1, N = Args.size(); I != N; ++I) {
4955  QualType ArgTy = Args[I]->getType();
4956  if (ArgTy->isObjectType() || ArgTy->isFunctionType())
4957  ArgTy = S.Context.getRValueReferenceType(ArgTy);
4958  OpaqueArgExprs.push_back(
4959  OpaqueValueExpr(Args[I]->getTypeLoc().getBeginLoc(),
4960  ArgTy.getNonLValueExprType(S.Context),
4961  Expr::getValueKindForType(ArgTy)));
4962  }
4963  for (Expr &E : OpaqueArgExprs)
4964  ArgExprs.push_back(&E);
4965 
4966  // Perform the initialization in an unevaluated context within a SFINAE
4967  // trap at translation unit scope.
4970  Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
4974  RParenLoc));
4975  InitializationSequence Init(S, To, InitKind, ArgExprs);
4976  if (Init.Failed())
4977  return false;
4978 
4979  ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs);
4980  if (Result.isInvalid() || SFINAE.hasErrorOccurred())
4981  return false;
4982 
4983  if (Kind == clang::TT_IsConstructible)
4984  return true;
4985 
4987  if (!T->isReferenceType())
4988  return false;
4989 
4990  return !Init.isDirectReferenceBinding();
4991  }
4992 
4994  return S.canThrow(Result.get()) == CT_Cannot;
4995 
4996  if (Kind == clang::TT_IsTriviallyConstructible) {
4997  // Under Objective-C ARC and Weak, if the destination has non-trivial
4998  // Objective-C lifetime, this is a non-trivial construction.
5000  return false;
5001 
5002  // The initialization succeeded; now make sure there are no non-trivial
5003  // calls.
5004  return !Result.get()->hasNonTrivialCall(S.Context);
5005  }
5006 
5007  llvm_unreachable("unhandled type trait");
5008  return false;
5009  }
5010  default: llvm_unreachable("not a TT");
5011  }
5012 
5013  return false;
5014 }
5015 
5018  SourceLocation RParenLoc) {
5019  QualType ResultType = Context.getLogicalOperationType();
5020 
5022  *this, Kind, KWLoc, Args[0]->getType()))
5023  return ExprError();
5024 
5025  bool Dependent = false;
5026  for (unsigned I = 0, N = Args.size(); I != N; ++I) {
5027  if (Args[I]->getType()->isDependentType()) {
5028  Dependent = true;
5029  break;
5030  }
5031  }
5032 
5033  bool Result = false;
5034  if (!Dependent)
5035  Result = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc);
5036 
5037  return TypeTraitExpr::Create(Context, ResultType, KWLoc, Kind, Args,
5038  RParenLoc, Result);
5039 }
5040 
5042  ArrayRef<ParsedType> Args,
5043  SourceLocation RParenLoc) {
5044  SmallVector<TypeSourceInfo *, 4> ConvertedArgs;
5045  ConvertedArgs.reserve(Args.size());
5046 
5047  for (unsigned I = 0, N = Args.size(); I != N; ++I) {
5048  TypeSourceInfo *TInfo;
5049  QualType T = GetTypeFromParser(Args[I], &TInfo);
5050  if (!TInfo)
5051  TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc);
5052 
5053  ConvertedArgs.push_back(TInfo);
5054  }
5055 
5056  return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc);
5057 }
5058 
5059 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
5060  QualType RhsT, SourceLocation KeyLoc) {
5061  assert(!LhsT->isDependentType() && !RhsT->isDependentType() &&
5062  "Cannot evaluate traits of dependent types");
5063 
5064  switch(BTT) {
5065  case BTT_IsBaseOf: {
5066  // C++0x [meta.rel]p2
5067  // Base is a base class of Derived without regard to cv-qualifiers or
5068  // Base and Derived are not unions and name the same class type without
5069  // regard to cv-qualifiers.
5070 
5071  const RecordType *lhsRecord = LhsT->getAs<RecordType>();
5072  const RecordType *rhsRecord = RhsT->getAs<RecordType>();
5073  if (!rhsRecord || !lhsRecord) {
5074  const ObjCObjectType *LHSObjTy = LhsT->getAs<ObjCObjectType>();
5075  const ObjCObjectType *RHSObjTy = RhsT->getAs<ObjCObjectType>();
5076  if (!LHSObjTy || !RHSObjTy)
5077  return false;
5078 
5079  ObjCInterfaceDecl *BaseInterface = LHSObjTy->getInterface();
5080  ObjCInterfaceDecl *DerivedInterface = RHSObjTy->getInterface();
5081  if (!BaseInterface || !DerivedInterface)
5082  return false;
5083 
5084  if (Self.RequireCompleteType(
5085  KeyLoc, RhsT, diag::err_incomplete_type_used_in_type_trait_expr))
5086  return false;
5087 
5088  return BaseInterface->isSuperClassOf(DerivedInterface);
5089  }
5090 
5091  assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT)
5092  == (lhsRecord == rhsRecord));
5093 
5094  // Unions are never base classes, and never have base classes.
5095  // It doesn't matter if they are complete or not. See PR#41843
5096  if (lhsRecord && lhsRecord->getDecl()->isUnion())
5097  return false;
5098  if (rhsRecord && rhsRecord->getDecl()->isUnion())
5099  return false;
5100 
5101  if (lhsRecord == rhsRecord)
5102  return true;
5103 
5104  // C++0x [meta.rel]p2:
5105  // If Base and Derived are class types and are different types
5106  // (ignoring possible cv-qualifiers) then Derived shall be a
5107  // complete type.
5108  if (Self.RequireCompleteType(KeyLoc, RhsT,
5109  diag::err_incomplete_type_used_in_type_trait_expr))
5110  return false;
5111 
5112  return cast<CXXRecordDecl>(rhsRecord->getDecl())
5113  ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl()));
5114  }
5115  case BTT_IsSame:
5116  return Self.Context.hasSameType(LhsT, RhsT);
5117  case BTT_TypeCompatible: {
5118  // GCC ignores cv-qualifiers on arrays for this builtin.
5119  Qualifiers LhsQuals, RhsQuals;
5120  QualType Lhs = Self.getASTContext().getUnqualifiedArrayType(LhsT, LhsQuals);
5121  QualType Rhs = Self.getASTContext().getUnqualifiedArrayType(RhsT, RhsQuals);
5122  return Self.Context.typesAreCompatible(Lhs, Rhs);
5123  }
5124  case BTT_IsConvertible:
5125  case BTT_IsConvertibleTo: {
5126  // C++0x [meta.rel]p4:
5127  // Given the following function prototype:
5128  //
5129  // template <class T>
5130  // typename add_rvalue_reference<T>::type create();
5131  //
5132  // the predicate condition for a template specialization
5133  // is_convertible<From, To> shall be satisfied if and only if
5134  // the return expression in the following code would be
5135  // well-formed, including any implicit conversions to the return
5136  // type of the function:
5137  //
5138  // To test() {
5139  // return create<From>();
5140  // }
5141  //
5142  // Access checking is performed as if in a context unrelated to To and
5143  // From. Only the validity of the immediate context of the expression
5144  // of the return-statement (including conversions to the return type)
5145  // is considered.
5146  //
5147  // We model the initialization as a copy-initialization of a temporary
5148  // of the appropriate type, which for this expression is identical to the
5149  // return statement (since NRVO doesn't apply).
5150 
5151  // Functions aren't allowed to return function or array types.
5152  if (RhsT->isFunctionType() || RhsT->isArrayType())
5153  return false;
5154 
5155  // A return statement in a void function must have void type.
5156  if (RhsT->isVoidType())
5157  return LhsT->isVoidType();
5158 
5159  // A function definition requires a complete, non-abstract return type.
5160  if (!Self.isCompleteType(KeyLoc, RhsT) || Self.isAbstractType(KeyLoc, RhsT))
5161  return false;
5162 
5163  // Compute the result of add_rvalue_reference.
5164  if (LhsT->isObjectType() || LhsT->isFunctionType())
5165  LhsT = Self.Context.getRValueReferenceType(LhsT);
5166 
5167  // Build a fake source and destination for initialization.
5169  OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
5171  Expr *FromPtr = &From;
5173  SourceLocation()));
5174 
5175  // Perform the initialization in an unevaluated context within a SFINAE
5176  // trap at translation unit scope.
5179  Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
5180  Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
5181  InitializationSequence Init(Self, To, Kind, FromPtr);
5182  if (Init.Failed())
5183  return false;
5184 
5185  ExprResult Result = Init.Perform(Self, To, Kind, FromPtr);
5186  return !Result.isInvalid() && !SFINAE.hasErrorOccurred();
5187  }
5188 
5189  case BTT_IsAssignable:
5192  // C++11 [meta.unary.prop]p3:
5193  // is_trivially_assignable is defined as:
5194  // is_assignable<T, U>::value is true and the assignment, as defined by
5195  // is_assignable, is known to call no operation that is not trivial
5196  //
5197  // is_assignable is defined as:
5198  // The expression declval<T>() = declval<U>() is well-formed when
5199  // treated as an unevaluated operand (Clause 5).
5200  //
5201  // For both, T and U shall be complete types, (possibly cv-qualified)
5202  // void, or arrays of unknown bound.
5203  if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() &&
5204  Self.RequireCompleteType(KeyLoc, LhsT,
5205  diag::err_incomplete_type_used_in_type_trait_expr))
5206  return false;
5207  if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() &&
5208  Self.RequireCompleteType(KeyLoc, RhsT,
5209  diag::err_incomplete_type_used_in_type_trait_expr))
5210  return false;
5211 
5212  // cv void is never assignable.
5213  if (LhsT->isVoidType() || RhsT->isVoidType())
5214  return false;
5215 
5216  // Build expressions that emulate the effect of declval<T>() and
5217  // declval<U>().
5218  if (LhsT->isObjectType() || LhsT->isFunctionType())
5219  LhsT = Self.Context.getRValueReferenceType(LhsT);
5220  if (RhsT->isObjectType() || RhsT->isFunctionType())
5221  RhsT = Self.Context.getRValueReferenceType(RhsT);
5222  OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
5224  OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context),
5226 
5227  // Attempt the assignment in an unevaluated context within a SFINAE
5228  // trap at translation unit scope.
5231  Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
5232  Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
5233  ExprResult Result = Self.BuildBinOp(/*S=*/nullptr, KeyLoc, BO_Assign, &Lhs,
5234  &Rhs);
5235  if (Result.isInvalid() || SFINAE.hasErrorOccurred())
5236  return false;
5237 
5238  if (BTT == BTT_IsAssignable)
5239  return true;
5240 
5241  if (BTT == BTT_IsNothrowAssignable)
5242  return Self.canThrow(Result.get()) == CT_Cannot;
5243 
5244  if (BTT == BTT_IsTriviallyAssignable) {
5245  // Under Objective-C ARC and Weak, if the destination has non-trivial
5246  // Objective-C lifetime, this is a non-trivial assignment.
5248  return false;
5249 
5250  return !Result.get()->hasNonTrivialCall(Self.Context);
5251  }
5252 
5253  llvm_unreachable("unhandled type trait");
5254  return false;
5255  }
5256  default: llvm_unreachable("not a BTT");
5257  }
5258  llvm_unreachable("Unknown type trait or not implemented");
5259 }
5260 
5262  SourceLocation KWLoc,
5263  ParsedType Ty,
5264  Expr* DimExpr,
5265  SourceLocation RParen) {
5266  TypeSourceInfo *TSInfo;
5267  QualType T = GetTypeFromParser(Ty, &TSInfo);
5268  if (!TSInfo)
5269  TSInfo = Context.getTrivialTypeSourceInfo(T);
5270 
5271  return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen);
5272 }
5273 
5274 static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT,
5275  QualType T, Expr *DimExpr,
5276  SourceLocation KeyLoc) {
5277  assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
5278 
5279  switch(ATT) {
5280  case ATT_ArrayRank:
5281  if (T->isArrayType()) {
5282  unsigned Dim = 0;
5283  while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
5284  ++Dim;
5285  T = AT->getElementType();
5286  }
5287  return Dim;
5288  }
5289  return 0;
5290 
5291  case ATT_ArrayExtent: {
5293  uint64_t Dim;
5294  if (Self.VerifyIntegerConstantExpression(DimExpr, &Value,
5295  diag::err_dimension_expr_not_constant_integer,
5296  false).isInvalid())
5297  return 0;
5298  if (Value.isSigned() && Value.isNegative()) {
5299  Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer)
5300  << DimExpr->getSourceRange();
5301  return 0;
5302  }
5303  Dim = Value.getLimitedValue();
5304 
5305  if (T->isArrayType()) {
5306  unsigned D = 0;
5307  bool Matched = false;
5308  while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
5309  if (Dim == D) {
5310  Matched = true;
5311  break;
5312  }
5313  ++D;
5314  T = AT->getElementType();
5315  }
5316 
5317  if (Matched && T->isArrayType()) {
5318  if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T))
5319  return CAT->getSize().getLimitedValue();
5320  }
5321  }
5322  return 0;
5323  }
5324  }
5325  llvm_unreachable("Unknown type trait or not implemented");
5326 }
5327 
5329  SourceLocation KWLoc,
5330  TypeSourceInfo *TSInfo,
5331  Expr* DimExpr,
5332  SourceLocation RParen) {
5333  QualType T = TSInfo->getType();
5334 
5335  // FIXME: This should likely be tracked as an APInt to remove any host
5336  // assumptions about the width of size_t on the target.
5337  uint64_t Value = 0;
5338  if (!T->isDependentType())
5339  Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc);
5340 
5341  // While the specification for these traits from the Embarcadero C++
5342  // compiler's documentation says the return type is 'unsigned int', Clang
5343  // returns 'size_t'. On Windows, the primary platform for the Embarcadero
5344  // compiler, there is no difference. On several other platforms this is an
5345  // important distinction.
5346  return new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, DimExpr,
5347  RParen, Context.getSizeType());
5348 }
5349 
5351  SourceLocation KWLoc,
5352  Expr *Queried,
5353  SourceLocation RParen) {
5354  // If error parsing the expression, ignore.
5355  if (!Queried)
5356  return ExprError();
5357 
5358  ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen);
5359 
5360  return Result;
5361 }
5362 
5364  switch (ET) {
5365  case ET_IsLValueExpr: return E->isLValue();
5366  case ET_IsRValueExpr: return E->isRValue();
5367  }
5368  llvm_unreachable("Expression trait not co