1 //===--- SemaExprCXX.cpp - Semantic Analysis for Expressions --------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
11 /// Implements semantic analysis for C++ expressions.
13 //===----------------------------------------------------------------------===//
15 #include "clang/Sema/SemaInternal.h"
16 #include "TreeTransform.h"
17 #include "TypeLocBuilder.h"
18 #include "clang/AST/ASTContext.h"
19 #include "clang/AST/ASTLambda.h"
20 #include "clang/AST/CXXInheritance.h"
21 #include "clang/AST/CharUnits.h"
22 #include "clang/AST/DeclObjC.h"
23 #include "clang/AST/ExprCXX.h"
24 #include "clang/AST/ExprObjC.h"
25 #include "clang/AST/RecursiveASTVisitor.h"
26 #include "clang/AST/TypeLoc.h"
27 #include "clang/Basic/AlignedAllocation.h"
28 #include "clang/Basic/PartialDiagnostic.h"
29 #include "clang/Basic/TargetInfo.h"
30 #include "clang/Lex/Preprocessor.h"
31 #include "clang/Sema/DeclSpec.h"
32 #include "clang/Sema/Initialization.h"
33 #include "clang/Sema/Lookup.h"
34 #include "clang/Sema/ParsedTemplate.h"
35 #include "clang/Sema/Scope.h"
36 #include "clang/Sema/ScopeInfo.h"
37 #include "clang/Sema/SemaLambda.h"
38 #include "clang/Sema/TemplateDeduction.h"
39 #include "llvm/ADT/APInt.h"
40 #include "llvm/ADT/STLExtras.h"
41 #include "llvm/Support/ErrorHandling.h"
42 using namespace clang;
45 /// Handle the result of the special case name lookup for inheriting
46 /// constructor declarations. 'NS::X::X' and 'NS::X<...>::X' are treated as
47 /// constructor names in member using declarations, even if 'X' is not the
48 /// name of the corresponding type.
49 ParsedType Sema::getInheritingConstructorName(CXXScopeSpec &SS,
50 SourceLocation NameLoc,
51 IdentifierInfo &Name) {
52 NestedNameSpecifier *NNS = SS.getScopeRep();
54 // Convert the nested-name-specifier into a type.
56 switch (NNS->getKind()) {
57 case NestedNameSpecifier::TypeSpec:
58 case NestedNameSpecifier::TypeSpecWithTemplate:
59 Type = QualType(NNS->getAsType(), 0);
62 case NestedNameSpecifier::Identifier:
63 // Strip off the last layer of the nested-name-specifier and build a
64 // typename type for it.
65 assert(NNS->getAsIdentifier() == &Name && "not a constructor name");
66 Type = Context.getDependentNameType(ETK_None, NNS->getPrefix(),
67 NNS->getAsIdentifier());
70 case NestedNameSpecifier::Global:
71 case NestedNameSpecifier::Super:
72 case NestedNameSpecifier::Namespace:
73 case NestedNameSpecifier::NamespaceAlias:
74 llvm_unreachable("Nested name specifier is not a type for inheriting ctor");
77 // This reference to the type is located entirely at the location of the
78 // final identifier in the qualified-id.
79 return CreateParsedType(Type,
80 Context.getTrivialTypeSourceInfo(Type, NameLoc));
83 ParsedType Sema::getConstructorName(IdentifierInfo &II,
84 SourceLocation NameLoc,
85 Scope *S, CXXScopeSpec &SS,
86 bool EnteringContext) {
87 CXXRecordDecl *CurClass = getCurrentClass(S, &SS);
88 assert(CurClass && &II == CurClass->getIdentifier() &&
89 "not a constructor name");
91 // When naming a constructor as a member of a dependent context (eg, in a
92 // friend declaration or an inherited constructor declaration), form an
93 // unresolved "typename" type.
94 if (CurClass->isDependentContext() && !EnteringContext) {
95 QualType T = Context.getDependentNameType(ETK_None, SS.getScopeRep(), &II);
96 return ParsedType::make(T);
99 if (SS.isNotEmpty() && RequireCompleteDeclContext(SS, CurClass))
102 // Find the injected-class-name declaration. Note that we make no attempt to
103 // diagnose cases where the injected-class-name is shadowed: the only
104 // declaration that can validly shadow the injected-class-name is a
105 // non-static data member, and if the class contains both a non-static data
106 // member and a constructor then it is ill-formed (we check that in
107 // CheckCompletedCXXClass).
108 CXXRecordDecl *InjectedClassName = nullptr;
109 for (NamedDecl *ND : CurClass->lookup(&II)) {
110 auto *RD = dyn_cast<CXXRecordDecl>(ND);
111 if (RD && RD->isInjectedClassName()) {
112 InjectedClassName = RD;
116 if (!InjectedClassName) {
117 if (!CurClass->isInvalidDecl()) {
118 // FIXME: RequireCompleteDeclContext doesn't check dependent contexts
119 // properly. Work around it here for now.
120 Diag(SS.getLastQualifierNameLoc(),
121 diag::err_incomplete_nested_name_spec) << CurClass << SS.getRange();
126 QualType T = Context.getTypeDeclType(InjectedClassName);
127 DiagnoseUseOfDecl(InjectedClassName, NameLoc);
128 MarkAnyDeclReferenced(NameLoc, InjectedClassName, /*OdrUse=*/false);
130 return ParsedType::make(T);
133 ParsedType Sema::getDestructorName(SourceLocation TildeLoc,
135 SourceLocation NameLoc,
136 Scope *S, CXXScopeSpec &SS,
137 ParsedType ObjectTypePtr,
138 bool EnteringContext) {
139 // Determine where to perform name lookup.
141 // FIXME: This area of the standard is very messy, and the current
142 // wording is rather unclear about which scopes we search for the
143 // destructor name; see core issues 399 and 555. Issue 399 in
144 // particular shows where the current description of destructor name
145 // lookup is completely out of line with existing practice, e.g.,
146 // this appears to be ill-formed:
149 // template <typename T> struct S {
154 // void f(N::S<int>* s) {
155 // s->N::S<int>::~S();
158 // See also PR6358 and PR6359.
159 // For this reason, we're currently only doing the C++03 version of this
160 // code; the C++0x version has to wait until we get a proper spec.
162 DeclContext *LookupCtx = nullptr;
163 bool isDependent = false;
164 bool LookInScope = false;
169 // If we have an object type, it's because we are in a
170 // pseudo-destructor-expression or a member access expression, and
171 // we know what type we're looking for.
173 SearchType = GetTypeFromParser(ObjectTypePtr);
176 NestedNameSpecifier *NNS = SS.getScopeRep();
178 bool AlreadySearched = false;
179 bool LookAtPrefix = true;
180 // C++11 [basic.lookup.qual]p6:
181 // If a pseudo-destructor-name (5.2.4) contains a nested-name-specifier,
182 // the type-names are looked up as types in the scope designated by the
183 // nested-name-specifier. Similarly, in a qualified-id of the form:
185 // nested-name-specifier[opt] class-name :: ~ class-name
187 // the second class-name is looked up in the same scope as the first.
189 // Here, we determine whether the code below is permitted to look at the
190 // prefix of the nested-name-specifier.
191 DeclContext *DC = computeDeclContext(SS, EnteringContext);
192 if (DC && DC->isFileContext()) {
193 AlreadySearched = true;
196 } else if (DC && isa<CXXRecordDecl>(DC)) {
197 LookAtPrefix = false;
201 // The second case from the C++03 rules quoted further above.
202 NestedNameSpecifier *Prefix = nullptr;
203 if (AlreadySearched) {
204 // Nothing left to do.
205 } else if (LookAtPrefix && (Prefix = NNS->getPrefix())) {
206 CXXScopeSpec PrefixSS;
207 PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data()));
208 LookupCtx = computeDeclContext(PrefixSS, EnteringContext);
209 isDependent = isDependentScopeSpecifier(PrefixSS);
210 } else if (ObjectTypePtr) {
211 LookupCtx = computeDeclContext(SearchType);
212 isDependent = SearchType->isDependentType();
214 LookupCtx = computeDeclContext(SS, EnteringContext);
215 isDependent = LookupCtx && LookupCtx->isDependentContext();
217 } else if (ObjectTypePtr) {
218 // C++ [basic.lookup.classref]p3:
219 // If the unqualified-id is ~type-name, the type-name is looked up
220 // in the context of the entire postfix-expression. If the type T
221 // of the object expression is of a class type C, the type-name is
222 // also looked up in the scope of class C. At least one of the
223 // lookups shall find a name that refers to (possibly
225 LookupCtx = computeDeclContext(SearchType);
226 isDependent = SearchType->isDependentType();
227 assert((isDependent || !SearchType->isIncompleteType()) &&
228 "Caller should have completed object type");
232 // Perform lookup into the current scope (only).
236 TypeDecl *NonMatchingTypeDecl = nullptr;
237 LookupResult Found(*this, &II, NameLoc, LookupOrdinaryName);
238 for (unsigned Step = 0; Step != 2; ++Step) {
239 // Look for the name first in the computed lookup context (if we
240 // have one) and, if that fails to find a match, in the scope (if
241 // we're allowed to look there).
243 if (Step == 0 && LookupCtx) {
244 if (RequireCompleteDeclContext(SS, LookupCtx))
246 LookupQualifiedName(Found, LookupCtx);
247 } else if (Step == 1 && LookInScope && S) {
248 LookupName(Found, S);
253 // FIXME: Should we be suppressing ambiguities here?
254 if (Found.isAmbiguous())
257 if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) {
258 QualType T = Context.getTypeDeclType(Type);
259 MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
261 if (SearchType.isNull() || SearchType->isDependentType() ||
262 Context.hasSameUnqualifiedType(T, SearchType)) {
263 // We found our type!
265 return CreateParsedType(T,
266 Context.getTrivialTypeSourceInfo(T, NameLoc));
269 if (!SearchType.isNull())
270 NonMatchingTypeDecl = Type;
273 // If the name that we found is a class template name, and it is
274 // the same name as the template name in the last part of the
275 // nested-name-specifier (if present) or the object type, then
276 // this is the destructor for that class.
277 // FIXME: This is a workaround until we get real drafting for core
278 // issue 399, for which there isn't even an obvious direction.
279 if (ClassTemplateDecl *Template = Found.getAsSingle<ClassTemplateDecl>()) {
280 QualType MemberOfType;
282 if (DeclContext *Ctx = computeDeclContext(SS, EnteringContext)) {
283 // Figure out the type of the context, if it has one.
284 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx))
285 MemberOfType = Context.getTypeDeclType(Record);
288 if (MemberOfType.isNull())
289 MemberOfType = SearchType;
291 if (MemberOfType.isNull())
294 // We're referring into a class template specialization. If the
295 // class template we found is the same as the template being
296 // specialized, we found what we are looking for.
297 if (const RecordType *Record = MemberOfType->getAs<RecordType>()) {
298 if (ClassTemplateSpecializationDecl *Spec
299 = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) {
300 if (Spec->getSpecializedTemplate()->getCanonicalDecl() ==
301 Template->getCanonicalDecl())
302 return CreateParsedType(
304 Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
310 // We're referring to an unresolved class template
311 // specialization. Determine whether we class template we found
312 // is the same as the template being specialized or, if we don't
313 // know which template is being specialized, that it at least
314 // has the same name.
315 if (const TemplateSpecializationType *SpecType
316 = MemberOfType->getAs<TemplateSpecializationType>()) {
317 TemplateName SpecName = SpecType->getTemplateName();
319 // The class template we found is the same template being
321 if (TemplateDecl *SpecTemplate = SpecName.getAsTemplateDecl()) {
322 if (SpecTemplate->getCanonicalDecl() == Template->getCanonicalDecl())
323 return CreateParsedType(
325 Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
330 // The class template we found has the same name as the
331 // (dependent) template name being specialized.
332 if (DependentTemplateName *DepTemplate
333 = SpecName.getAsDependentTemplateName()) {
334 if (DepTemplate->isIdentifier() &&
335 DepTemplate->getIdentifier() == Template->getIdentifier())
336 return CreateParsedType(
338 Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
347 // We didn't find our type, but that's okay: it's dependent
350 // FIXME: What if we have no nested-name-specifier?
351 QualType T = CheckTypenameType(ETK_None, SourceLocation(),
352 SS.getWithLocInContext(Context),
354 return ParsedType::make(T);
357 if (NonMatchingTypeDecl) {
358 QualType T = Context.getTypeDeclType(NonMatchingTypeDecl);
359 Diag(NameLoc, diag::err_destructor_expr_type_mismatch)
361 Diag(NonMatchingTypeDecl->getLocation(), diag::note_destructor_type_here)
363 } else if (ObjectTypePtr)
364 Diag(NameLoc, diag::err_ident_in_dtor_not_a_type)
367 SemaDiagnosticBuilder DtorDiag = Diag(NameLoc,
368 diag::err_destructor_class_name);
370 const DeclContext *Ctx = S->getEntity();
371 if (const CXXRecordDecl *Class = dyn_cast_or_null<CXXRecordDecl>(Ctx))
372 DtorDiag << FixItHint::CreateReplacement(SourceRange(NameLoc),
373 Class->getNameAsString());
380 ParsedType Sema::getDestructorTypeForDecltype(const DeclSpec &DS,
381 ParsedType ObjectType) {
382 if (DS.getTypeSpecType() == DeclSpec::TST_error)
385 if (DS.getTypeSpecType() == DeclSpec::TST_decltype_auto) {
386 Diag(DS.getTypeSpecTypeLoc(), diag::err_decltype_auto_invalid);
390 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype &&
391 "unexpected type in getDestructorType");
392 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
394 // If we know the type of the object, check that the correct destructor
395 // type was named now; we can give better diagnostics this way.
396 QualType SearchType = GetTypeFromParser(ObjectType);
397 if (!SearchType.isNull() && !SearchType->isDependentType() &&
398 !Context.hasSameUnqualifiedType(T, SearchType)) {
399 Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch)
404 return ParsedType::make(T);
407 bool Sema::checkLiteralOperatorId(const CXXScopeSpec &SS,
408 const UnqualifiedId &Name) {
409 assert(Name.getKind() == UnqualifiedIdKind::IK_LiteralOperatorId);
414 switch (SS.getScopeRep()->getKind()) {
415 case NestedNameSpecifier::Identifier:
416 case NestedNameSpecifier::TypeSpec:
417 case NestedNameSpecifier::TypeSpecWithTemplate:
418 // Per C++11 [over.literal]p2, literal operators can only be declared at
419 // namespace scope. Therefore, this unqualified-id cannot name anything.
420 // Reject it early, because we have no AST representation for this in the
421 // case where the scope is dependent.
422 Diag(Name.getLocStart(), diag::err_literal_operator_id_outside_namespace)
426 case NestedNameSpecifier::Global:
427 case NestedNameSpecifier::Super:
428 case NestedNameSpecifier::Namespace:
429 case NestedNameSpecifier::NamespaceAlias:
433 llvm_unreachable("unknown nested name specifier kind");
436 /// Build a C++ typeid expression with a type operand.
437 ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
438 SourceLocation TypeidLoc,
439 TypeSourceInfo *Operand,
440 SourceLocation RParenLoc) {
441 // C++ [expr.typeid]p4:
442 // The top-level cv-qualifiers of the lvalue expression or the type-id
443 // that is the operand of typeid are always ignored.
444 // If the type of the type-id is a class type or a reference to a class
445 // type, the class shall be completely-defined.
448 = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(),
450 if (T->getAs<RecordType>() &&
451 RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
454 if (T->isVariablyModifiedType())
455 return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid) << T);
457 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), Operand,
458 SourceRange(TypeidLoc, RParenLoc));
461 /// Build a C++ typeid expression with an expression operand.
462 ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
463 SourceLocation TypeidLoc,
465 SourceLocation RParenLoc) {
466 bool WasEvaluated = false;
467 if (E && !E->isTypeDependent()) {
468 if (E->getType()->isPlaceholderType()) {
469 ExprResult result = CheckPlaceholderExpr(E);
470 if (result.isInvalid()) return ExprError();
474 QualType T = E->getType();
475 if (const RecordType *RecordT = T->getAs<RecordType>()) {
476 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl());
477 // C++ [expr.typeid]p3:
478 // [...] If the type of the expression is a class type, the class
479 // shall be completely-defined.
480 if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
483 // C++ [expr.typeid]p3:
484 // When typeid is applied to an expression other than an glvalue of a
485 // polymorphic class type [...] [the] expression is an unevaluated
487 if (RecordD->isPolymorphic() && E->isGLValue()) {
488 // The subexpression is potentially evaluated; switch the context
489 // and recheck the subexpression.
490 ExprResult Result = TransformToPotentiallyEvaluated(E);
491 if (Result.isInvalid()) return ExprError();
494 // We require a vtable to query the type at run time.
495 MarkVTableUsed(TypeidLoc, RecordD);
500 // C++ [expr.typeid]p4:
501 // [...] If the type of the type-id is a reference to a possibly
502 // cv-qualified type, the result of the typeid expression refers to a
503 // std::type_info object representing the cv-unqualified referenced
506 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals);
507 if (!Context.hasSameType(T, UnqualT)) {
509 E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).get();
513 if (E->getType()->isVariablyModifiedType())
514 return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid)
516 else if (!inTemplateInstantiation() &&
517 E->HasSideEffects(Context, WasEvaluated)) {
518 // The expression operand for typeid is in an unevaluated expression
519 // context, so side effects could result in unintended consequences.
520 Diag(E->getExprLoc(), WasEvaluated
521 ? diag::warn_side_effects_typeid
522 : diag::warn_side_effects_unevaluated_context);
525 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), E,
526 SourceRange(TypeidLoc, RParenLoc));
529 /// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression);
531 Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc,
532 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
533 // OpenCL C++ 1.0 s2.9: typeid is not supported.
534 if (getLangOpts().OpenCLCPlusPlus) {
535 return ExprError(Diag(OpLoc, diag::err_openclcxx_not_supported)
539 // Find the std::type_info type.
540 if (!getStdNamespace())
541 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
543 if (!CXXTypeInfoDecl) {
544 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info");
545 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName);
546 LookupQualifiedName(R, getStdNamespace());
547 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
548 // Microsoft's typeinfo doesn't have type_info in std but in the global
549 // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153.
550 if (!CXXTypeInfoDecl && LangOpts.MSVCCompat) {
551 LookupQualifiedName(R, Context.getTranslationUnitDecl());
552 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
554 if (!CXXTypeInfoDecl)
555 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
558 if (!getLangOpts().RTTI) {
559 return ExprError(Diag(OpLoc, diag::err_no_typeid_with_fno_rtti));
562 QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl);
565 // The operand is a type; handle it as such.
566 TypeSourceInfo *TInfo = nullptr;
567 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
573 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
575 return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc);
578 // The operand is an expression.
579 return BuildCXXTypeId(TypeInfoType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
582 /// Grabs __declspec(uuid()) off a type, or returns 0 if we cannot resolve to
585 getUuidAttrOfType(Sema &SemaRef, QualType QT,
586 llvm::SmallSetVector<const UuidAttr *, 1> &UuidAttrs) {
587 // Optionally remove one level of pointer, reference or array indirection.
588 const Type *Ty = QT.getTypePtr();
589 if (QT->isPointerType() || QT->isReferenceType())
590 Ty = QT->getPointeeType().getTypePtr();
591 else if (QT->isArrayType())
592 Ty = Ty->getBaseElementTypeUnsafe();
594 const auto *TD = Ty->getAsTagDecl();
598 if (const auto *Uuid = TD->getMostRecentDecl()->getAttr<UuidAttr>()) {
599 UuidAttrs.insert(Uuid);
603 // __uuidof can grab UUIDs from template arguments.
604 if (const auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(TD)) {
605 const TemplateArgumentList &TAL = CTSD->getTemplateArgs();
606 for (const TemplateArgument &TA : TAL.asArray()) {
607 const UuidAttr *UuidForTA = nullptr;
608 if (TA.getKind() == TemplateArgument::Type)
609 getUuidAttrOfType(SemaRef, TA.getAsType(), UuidAttrs);
610 else if (TA.getKind() == TemplateArgument::Declaration)
611 getUuidAttrOfType(SemaRef, TA.getAsDecl()->getType(), UuidAttrs);
614 UuidAttrs.insert(UuidForTA);
619 /// Build a Microsoft __uuidof expression with a type operand.
620 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType,
621 SourceLocation TypeidLoc,
622 TypeSourceInfo *Operand,
623 SourceLocation RParenLoc) {
625 if (!Operand->getType()->isDependentType()) {
626 llvm::SmallSetVector<const UuidAttr *, 1> UuidAttrs;
627 getUuidAttrOfType(*this, Operand->getType(), UuidAttrs);
628 if (UuidAttrs.empty())
629 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
630 if (UuidAttrs.size() > 1)
631 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
632 UuidStr = UuidAttrs.back()->getGuid();
635 return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), Operand, UuidStr,
636 SourceRange(TypeidLoc, RParenLoc));
639 /// Build a Microsoft __uuidof expression with an expression operand.
640 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType,
641 SourceLocation TypeidLoc,
643 SourceLocation RParenLoc) {
645 if (!E->getType()->isDependentType()) {
646 if (E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
647 UuidStr = "00000000-0000-0000-0000-000000000000";
649 llvm::SmallSetVector<const UuidAttr *, 1> UuidAttrs;
650 getUuidAttrOfType(*this, E->getType(), UuidAttrs);
651 if (UuidAttrs.empty())
652 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
653 if (UuidAttrs.size() > 1)
654 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
655 UuidStr = UuidAttrs.back()->getGuid();
659 return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), E, UuidStr,
660 SourceRange(TypeidLoc, RParenLoc));
663 /// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression);
665 Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc,
666 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
667 // If MSVCGuidDecl has not been cached, do the lookup.
669 IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID");
670 LookupResult R(*this, GuidII, SourceLocation(), LookupTagName);
671 LookupQualifiedName(R, Context.getTranslationUnitDecl());
672 MSVCGuidDecl = R.getAsSingle<RecordDecl>();
674 return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof));
677 QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl);
680 // The operand is a type; handle it as such.
681 TypeSourceInfo *TInfo = nullptr;
682 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
688 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
690 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc);
693 // The operand is an expression.
694 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
697 /// ActOnCXXBoolLiteral - Parse {true,false} literals.
699 Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
700 assert((Kind == tok::kw_true || Kind == tok::kw_false) &&
701 "Unknown C++ Boolean value!");
703 CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc);
706 /// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
708 Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) {
709 return new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
712 /// ActOnCXXThrow - Parse throw expressions.
714 Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) {
715 bool IsThrownVarInScope = false;
717 // C++0x [class.copymove]p31:
718 // When certain criteria are met, an implementation is allowed to omit the
719 // copy/move construction of a class object [...]
721 // - in a throw-expression, when the operand is the name of a
722 // non-volatile automatic object (other than a function or catch-
723 // clause parameter) whose scope does not extend beyond the end of the
724 // innermost enclosing try-block (if there is one), the copy/move
725 // operation from the operand to the exception object (15.1) can be
726 // omitted by constructing the automatic object directly into the
728 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens()))
729 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
730 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) {
731 for( ; S; S = S->getParent()) {
732 if (S->isDeclScope(Var)) {
733 IsThrownVarInScope = true;
738 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope |
739 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope |
747 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope);
750 ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex,
751 bool IsThrownVarInScope) {
752 // Don't report an error if 'throw' is used in system headers.
753 if (!getLangOpts().CXXExceptions &&
754 !getSourceManager().isInSystemHeader(OpLoc) &&
755 (!getLangOpts().OpenMPIsDevice ||
756 !getLangOpts().OpenMPHostCXXExceptions ||
757 isInOpenMPTargetExecutionDirective() ||
758 isInOpenMPDeclareTargetContext()))
759 Diag(OpLoc, diag::err_exceptions_disabled) << "throw";
761 // Exceptions aren't allowed in CUDA device code.
762 if (getLangOpts().CUDA)
763 CUDADiagIfDeviceCode(OpLoc, diag::err_cuda_device_exceptions)
764 << "throw" << CurrentCUDATarget();
766 if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
767 Diag(OpLoc, diag::err_omp_simd_region_cannot_use_stmt) << "throw";
769 if (Ex && !Ex->isTypeDependent()) {
770 QualType ExceptionObjectTy = Context.getExceptionObjectType(Ex->getType());
771 if (CheckCXXThrowOperand(OpLoc, ExceptionObjectTy, Ex))
774 // Initialize the exception result. This implicitly weeds out
775 // abstract types or types with inaccessible copy constructors.
777 // C++0x [class.copymove]p31:
778 // When certain criteria are met, an implementation is allowed to omit the
779 // copy/move construction of a class object [...]
781 // - in a throw-expression, when the operand is the name of a
782 // non-volatile automatic object (other than a function or
784 // parameter) whose scope does not extend beyond the end of the
785 // innermost enclosing try-block (if there is one), the copy/move
786 // operation from the operand to the exception object (15.1) can be
787 // omitted by constructing the automatic object directly into the
789 const VarDecl *NRVOVariable = nullptr;
790 if (IsThrownVarInScope)
791 NRVOVariable = getCopyElisionCandidate(QualType(), Ex, CES_Strict);
793 InitializedEntity Entity = InitializedEntity::InitializeException(
794 OpLoc, ExceptionObjectTy,
795 /*NRVO=*/NRVOVariable != nullptr);
796 ExprResult Res = PerformMoveOrCopyInitialization(
797 Entity, NRVOVariable, QualType(), Ex, IsThrownVarInScope);
804 CXXThrowExpr(Ex, Context.VoidTy, OpLoc, IsThrownVarInScope);
808 collectPublicBases(CXXRecordDecl *RD,
809 llvm::DenseMap<CXXRecordDecl *, unsigned> &SubobjectsSeen,
810 llvm::SmallPtrSetImpl<CXXRecordDecl *> &VBases,
811 llvm::SetVector<CXXRecordDecl *> &PublicSubobjectsSeen,
812 bool ParentIsPublic) {
813 for (const CXXBaseSpecifier &BS : RD->bases()) {
814 CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
816 // Virtual bases constitute the same subobject. Non-virtual bases are
817 // always distinct subobjects.
819 NewSubobject = VBases.insert(BaseDecl).second;
824 ++SubobjectsSeen[BaseDecl];
826 // Only add subobjects which have public access throughout the entire chain.
827 bool PublicPath = ParentIsPublic && BS.getAccessSpecifier() == AS_public;
829 PublicSubobjectsSeen.insert(BaseDecl);
831 // Recurse on to each base subobject.
832 collectPublicBases(BaseDecl, SubobjectsSeen, VBases, PublicSubobjectsSeen,
837 static void getUnambiguousPublicSubobjects(
838 CXXRecordDecl *RD, llvm::SmallVectorImpl<CXXRecordDecl *> &Objects) {
839 llvm::DenseMap<CXXRecordDecl *, unsigned> SubobjectsSeen;
840 llvm::SmallSet<CXXRecordDecl *, 2> VBases;
841 llvm::SetVector<CXXRecordDecl *> PublicSubobjectsSeen;
842 SubobjectsSeen[RD] = 1;
843 PublicSubobjectsSeen.insert(RD);
844 collectPublicBases(RD, SubobjectsSeen, VBases, PublicSubobjectsSeen,
845 /*ParentIsPublic=*/true);
847 for (CXXRecordDecl *PublicSubobject : PublicSubobjectsSeen) {
848 // Skip ambiguous objects.
849 if (SubobjectsSeen[PublicSubobject] > 1)
852 Objects.push_back(PublicSubobject);
856 /// CheckCXXThrowOperand - Validate the operand of a throw.
857 bool Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc,
858 QualType ExceptionObjectTy, Expr *E) {
859 // If the type of the exception would be an incomplete type or a pointer
860 // to an incomplete type other than (cv) void the program is ill-formed.
861 QualType Ty = ExceptionObjectTy;
862 bool isPointer = false;
863 if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
864 Ty = Ptr->getPointeeType();
867 if (!isPointer || !Ty->isVoidType()) {
868 if (RequireCompleteType(ThrowLoc, Ty,
869 isPointer ? diag::err_throw_incomplete_ptr
870 : diag::err_throw_incomplete,
871 E->getSourceRange()))
874 if (RequireNonAbstractType(ThrowLoc, ExceptionObjectTy,
875 diag::err_throw_abstract_type, E))
879 // If the exception has class type, we need additional handling.
880 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
884 // If we are throwing a polymorphic class type or pointer thereof,
885 // exception handling will make use of the vtable.
886 MarkVTableUsed(ThrowLoc, RD);
888 // If a pointer is thrown, the referenced object will not be destroyed.
892 // If the class has a destructor, we must be able to call it.
893 if (!RD->hasIrrelevantDestructor()) {
894 if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
895 MarkFunctionReferenced(E->getExprLoc(), Destructor);
896 CheckDestructorAccess(E->getExprLoc(), Destructor,
897 PDiag(diag::err_access_dtor_exception) << Ty);
898 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
903 // The MSVC ABI creates a list of all types which can catch the exception
904 // object. This list also references the appropriate copy constructor to call
905 // if the object is caught by value and has a non-trivial copy constructor.
906 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
907 // We are only interested in the public, unambiguous bases contained within
908 // the exception object. Bases which are ambiguous or otherwise
909 // inaccessible are not catchable types.
910 llvm::SmallVector<CXXRecordDecl *, 2> UnambiguousPublicSubobjects;
911 getUnambiguousPublicSubobjects(RD, UnambiguousPublicSubobjects);
913 for (CXXRecordDecl *Subobject : UnambiguousPublicSubobjects) {
914 // Attempt to lookup the copy constructor. Various pieces of machinery
915 // will spring into action, like template instantiation, which means this
916 // cannot be a simple walk of the class's decls. Instead, we must perform
917 // lookup and overload resolution.
918 CXXConstructorDecl *CD = LookupCopyingConstructor(Subobject, 0);
922 // Mark the constructor referenced as it is used by this throw expression.
923 MarkFunctionReferenced(E->getExprLoc(), CD);
925 // Skip this copy constructor if it is trivial, we don't need to record it
926 // in the catchable type data.
930 // The copy constructor is non-trivial, create a mapping from this class
931 // type to this constructor.
932 // N.B. The selection of copy constructor is not sensitive to this
933 // particular throw-site. Lookup will be performed at the catch-site to
934 // ensure that the copy constructor is, in fact, accessible (via
935 // friendship or any other means).
936 Context.addCopyConstructorForExceptionObject(Subobject, CD);
938 // We don't keep the instantiated default argument expressions around so
939 // we must rebuild them here.
940 for (unsigned I = 1, E = CD->getNumParams(); I != E; ++I) {
941 if (CheckCXXDefaultArgExpr(ThrowLoc, CD, CD->getParamDecl(I)))
950 static QualType adjustCVQualifiersForCXXThisWithinLambda(
951 ArrayRef<FunctionScopeInfo *> FunctionScopes, QualType ThisTy,
952 DeclContext *CurSemaContext, ASTContext &ASTCtx) {
954 QualType ClassType = ThisTy->getPointeeType();
955 LambdaScopeInfo *CurLSI = nullptr;
956 DeclContext *CurDC = CurSemaContext;
958 // Iterate through the stack of lambdas starting from the innermost lambda to
959 // the outermost lambda, checking if '*this' is ever captured by copy - since
960 // that could change the cv-qualifiers of the '*this' object.
961 // The object referred to by '*this' starts out with the cv-qualifiers of its
962 // member function. We then start with the innermost lambda and iterate
963 // outward checking to see if any lambda performs a by-copy capture of '*this'
964 // - and if so, any nested lambda must respect the 'constness' of that
965 // capturing lamdbda's call operator.
968 // Since the FunctionScopeInfo stack is representative of the lexical
969 // nesting of the lambda expressions during initial parsing (and is the best
970 // place for querying information about captures about lambdas that are
971 // partially processed) and perhaps during instantiation of function templates
972 // that contain lambda expressions that need to be transformed BUT not
973 // necessarily during instantiation of a nested generic lambda's function call
974 // operator (which might even be instantiated at the end of the TU) - at which
975 // time the DeclContext tree is mature enough to query capture information
976 // reliably - we use a two pronged approach to walk through all the lexically
977 // enclosing lambda expressions:
979 // 1) Climb down the FunctionScopeInfo stack as long as each item represents
980 // a Lambda (i.e. LambdaScopeInfo) AND each LSI's 'closure-type' is lexically
981 // enclosed by the call-operator of the LSI below it on the stack (while
982 // tracking the enclosing DC for step 2 if needed). Note the topmost LSI on
983 // the stack represents the innermost lambda.
985 // 2) If we run out of enclosing LSI's, check if the enclosing DeclContext
986 // represents a lambda's call operator. If it does, we must be instantiating
987 // a generic lambda's call operator (represented by the Current LSI, and
988 // should be the only scenario where an inconsistency between the LSI and the
989 // DeclContext should occur), so climb out the DeclContexts if they
990 // represent lambdas, while querying the corresponding closure types
991 // regarding capture information.
993 // 1) Climb down the function scope info stack.
994 for (int I = FunctionScopes.size();
995 I-- && isa<LambdaScopeInfo>(FunctionScopes[I]) &&
996 (!CurLSI || !CurLSI->Lambda || CurLSI->Lambda->getDeclContext() ==
997 cast<LambdaScopeInfo>(FunctionScopes[I])->CallOperator);
998 CurDC = getLambdaAwareParentOfDeclContext(CurDC)) {
999 CurLSI = cast<LambdaScopeInfo>(FunctionScopes[I]);
1001 if (!CurLSI->isCXXThisCaptured())
1004 auto C = CurLSI->getCXXThisCapture();
1006 if (C.isCopyCapture()) {
1007 ClassType.removeLocalCVRQualifiers(Qualifiers::CVRMask);
1008 if (CurLSI->CallOperator->isConst())
1009 ClassType.addConst();
1010 return ASTCtx.getPointerType(ClassType);
1014 // 2) We've run out of ScopeInfos but check if CurDC is a lambda (which can
1015 // happen during instantiation of its nested generic lambda call operator)
1016 if (isLambdaCallOperator(CurDC)) {
1017 assert(CurLSI && "While computing 'this' capture-type for a generic "
1018 "lambda, we must have a corresponding LambdaScopeInfo");
1019 assert(isGenericLambdaCallOperatorSpecialization(CurLSI->CallOperator) &&
1020 "While computing 'this' capture-type for a generic lambda, when we "
1021 "run out of enclosing LSI's, yet the enclosing DC is a "
1022 "lambda-call-operator we must be (i.e. Current LSI) in a generic "
1023 "lambda call oeprator");
1024 assert(CurDC == getLambdaAwareParentOfDeclContext(CurLSI->CallOperator));
1026 auto IsThisCaptured =
1027 [](CXXRecordDecl *Closure, bool &IsByCopy, bool &IsConst) {
1030 for (auto &&C : Closure->captures()) {
1031 if (C.capturesThis()) {
1032 if (C.getCaptureKind() == LCK_StarThis)
1034 if (Closure->getLambdaCallOperator()->isConst())
1042 bool IsByCopyCapture = false;
1043 bool IsConstCapture = false;
1044 CXXRecordDecl *Closure = cast<CXXRecordDecl>(CurDC->getParent());
1046 IsThisCaptured(Closure, IsByCopyCapture, IsConstCapture)) {
1047 if (IsByCopyCapture) {
1048 ClassType.removeLocalCVRQualifiers(Qualifiers::CVRMask);
1050 ClassType.addConst();
1051 return ASTCtx.getPointerType(ClassType);
1053 Closure = isLambdaCallOperator(Closure->getParent())
1054 ? cast<CXXRecordDecl>(Closure->getParent()->getParent())
1058 return ASTCtx.getPointerType(ClassType);
1061 QualType Sema::getCurrentThisType() {
1062 DeclContext *DC = getFunctionLevelDeclContext();
1063 QualType ThisTy = CXXThisTypeOverride;
1065 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) {
1066 if (method && method->isInstance())
1067 ThisTy = method->getThisType(Context);
1070 if (ThisTy.isNull() && isLambdaCallOperator(CurContext) &&
1071 inTemplateInstantiation()) {
1073 assert(isa<CXXRecordDecl>(DC) &&
1074 "Trying to get 'this' type from static method?");
1076 // This is a lambda call operator that is being instantiated as a default
1077 // initializer. DC must point to the enclosing class type, so we can recover
1078 // the 'this' type from it.
1080 QualType ClassTy = Context.getTypeDeclType(cast<CXXRecordDecl>(DC));
1081 // There are no cv-qualifiers for 'this' within default initializers,
1082 // per [expr.prim.general]p4.
1083 ThisTy = Context.getPointerType(ClassTy);
1086 // If we are within a lambda's call operator, the cv-qualifiers of 'this'
1087 // might need to be adjusted if the lambda or any of its enclosing lambda's
1088 // captures '*this' by copy.
1089 if (!ThisTy.isNull() && isLambdaCallOperator(CurContext))
1090 return adjustCVQualifiersForCXXThisWithinLambda(FunctionScopes, ThisTy,
1091 CurContext, Context);
1095 Sema::CXXThisScopeRAII::CXXThisScopeRAII(Sema &S,
1097 unsigned CXXThisTypeQuals,
1099 : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false)
1101 if (!Enabled || !ContextDecl)
1104 CXXRecordDecl *Record = nullptr;
1105 if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl))
1106 Record = Template->getTemplatedDecl();
1108 Record = cast<CXXRecordDecl>(ContextDecl);
1110 // We care only for CVR qualifiers here, so cut everything else.
1111 CXXThisTypeQuals &= Qualifiers::FastMask;
1112 S.CXXThisTypeOverride
1113 = S.Context.getPointerType(
1114 S.Context.getRecordType(Record).withCVRQualifiers(CXXThisTypeQuals));
1116 this->Enabled = true;
1120 Sema::CXXThisScopeRAII::~CXXThisScopeRAII() {
1122 S.CXXThisTypeOverride = OldCXXThisTypeOverride;
1126 static Expr *captureThis(Sema &S, ASTContext &Context, RecordDecl *RD,
1127 QualType ThisTy, SourceLocation Loc,
1128 const bool ByCopy) {
1130 QualType AdjustedThisTy = ThisTy;
1131 // The type of the corresponding data member (not a 'this' pointer if 'by
1133 QualType CaptureThisFieldTy = ThisTy;
1135 // If we are capturing the object referred to by '*this' by copy, ignore any
1136 // cv qualifiers inherited from the type of the member function for the type
1137 // of the closure-type's corresponding data member and any use of 'this'.
1138 CaptureThisFieldTy = ThisTy->getPointeeType();
1139 CaptureThisFieldTy.removeLocalCVRQualifiers(Qualifiers::CVRMask);
1140 AdjustedThisTy = Context.getPointerType(CaptureThisFieldTy);
1143 FieldDecl *Field = FieldDecl::Create(
1144 Context, RD, Loc, Loc, nullptr, CaptureThisFieldTy,
1145 Context.getTrivialTypeSourceInfo(CaptureThisFieldTy, Loc), nullptr, false,
1148 Field->setImplicit(true);
1149 Field->setAccess(AS_private);
1152 new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit*/ true);
1154 Expr *StarThis = S.CreateBuiltinUnaryOp(Loc,
1157 InitializedEntity Entity = InitializedEntity::InitializeLambdaCapture(
1158 nullptr, CaptureThisFieldTy, Loc);
1159 InitializationKind InitKind = InitializationKind::CreateDirect(Loc, Loc, Loc);
1160 InitializationSequence Init(S, Entity, InitKind, StarThis);
1161 ExprResult ER = Init.Perform(S, Entity, InitKind, StarThis);
1162 if (ER.isInvalid()) return nullptr;
1168 bool Sema::CheckCXXThisCapture(SourceLocation Loc, const bool Explicit,
1169 bool BuildAndDiagnose, const unsigned *const FunctionScopeIndexToStopAt,
1170 const bool ByCopy) {
1171 // We don't need to capture this in an unevaluated context.
1172 if (isUnevaluatedContext() && !Explicit)
1175 assert((!ByCopy || Explicit) && "cannot implicitly capture *this by value");
1177 const int MaxFunctionScopesIndex = FunctionScopeIndexToStopAt
1178 ? *FunctionScopeIndexToStopAt
1179 : FunctionScopes.size() - 1;
1181 // Check that we can capture the *enclosing object* (referred to by '*this')
1182 // by the capturing-entity/closure (lambda/block/etc) at
1183 // MaxFunctionScopesIndex-deep on the FunctionScopes stack.
1185 // Note: The *enclosing object* can only be captured by-value by a
1186 // closure that is a lambda, using the explicit notation:
1188 // Every other capture of the *enclosing object* results in its by-reference
1191 // For a closure 'L' (at MaxFunctionScopesIndex in the FunctionScopes
1192 // stack), we can capture the *enclosing object* only if:
1193 // - 'L' has an explicit byref or byval capture of the *enclosing object*
1194 // - or, 'L' has an implicit capture.
1196 // -- there is no enclosing closure
1197 // -- or, there is some enclosing closure 'E' that has already captured the
1198 // *enclosing object*, and every intervening closure (if any) between 'E'
1199 // and 'L' can implicitly capture the *enclosing object*.
1200 // -- or, every enclosing closure can implicitly capture the
1201 // *enclosing object*
1204 unsigned NumCapturingClosures = 0;
1205 for (int idx = MaxFunctionScopesIndex; idx >= 0; idx--) {
1206 if (CapturingScopeInfo *CSI =
1207 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) {
1208 if (CSI->CXXThisCaptureIndex != 0) {
1209 // 'this' is already being captured; there isn't anything more to do.
1210 CSI->Captures[CSI->CXXThisCaptureIndex - 1].markUsed(BuildAndDiagnose);
1213 LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI);
1214 if (LSI && isGenericLambdaCallOperatorSpecialization(LSI->CallOperator)) {
1215 // This context can't implicitly capture 'this'; fail out.
1216 if (BuildAndDiagnose)
1217 Diag(Loc, diag::err_this_capture)
1218 << (Explicit && idx == MaxFunctionScopesIndex);
1221 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref ||
1222 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval ||
1223 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block ||
1224 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_CapturedRegion ||
1225 (Explicit && idx == MaxFunctionScopesIndex)) {
1226 // Regarding (Explicit && idx == MaxFunctionScopesIndex): only the first
1227 // iteration through can be an explicit capture, all enclosing closures,
1228 // if any, must perform implicit captures.
1230 // This closure can capture 'this'; continue looking upwards.
1231 NumCapturingClosures++;
1234 // This context can't implicitly capture 'this'; fail out.
1235 if (BuildAndDiagnose)
1236 Diag(Loc, diag::err_this_capture)
1237 << (Explicit && idx == MaxFunctionScopesIndex);
1242 if (!BuildAndDiagnose) return false;
1244 // If we got here, then the closure at MaxFunctionScopesIndex on the
1245 // FunctionScopes stack, can capture the *enclosing object*, so capture it
1246 // (including implicit by-reference captures in any enclosing closures).
1248 // In the loop below, respect the ByCopy flag only for the closure requesting
1249 // the capture (i.e. first iteration through the loop below). Ignore it for
1250 // all enclosing closure's up to NumCapturingClosures (since they must be
1251 // implicitly capturing the *enclosing object* by reference (see loop
1254 dyn_cast<LambdaScopeInfo>(FunctionScopes[MaxFunctionScopesIndex])) &&
1255 "Only a lambda can capture the enclosing object (referred to by "
1257 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated
1259 QualType ThisTy = getCurrentThisType();
1260 for (int idx = MaxFunctionScopesIndex; NumCapturingClosures;
1261 --idx, --NumCapturingClosures) {
1262 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]);
1263 Expr *ThisExpr = nullptr;
1265 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI)) {
1266 // For lambda expressions, build a field and an initializing expression,
1267 // and capture the *enclosing object* by copy only if this is the first
1269 ThisExpr = captureThis(*this, Context, LSI->Lambda, ThisTy, Loc,
1270 ByCopy && idx == MaxFunctionScopesIndex);
1272 } else if (CapturedRegionScopeInfo *RSI
1273 = dyn_cast<CapturedRegionScopeInfo>(FunctionScopes[idx]))
1275 captureThis(*this, Context, RSI->TheRecordDecl, ThisTy, Loc,
1278 bool isNested = NumCapturingClosures > 1;
1279 CSI->addThisCapture(isNested, Loc, ThisExpr, ByCopy);
1284 ExprResult Sema::ActOnCXXThis(SourceLocation Loc) {
1285 /// C++ 9.3.2: In the body of a non-static member function, the keyword this
1286 /// is a non-lvalue expression whose value is the address of the object for
1287 /// which the function is called.
1289 QualType ThisTy = getCurrentThisType();
1290 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use);
1292 CheckCXXThisCapture(Loc);
1293 return new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false);
1296 bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) {
1297 // If we're outside the body of a member function, then we'll have a specified
1299 if (CXXThisTypeOverride.isNull())
1302 // Determine whether we're looking into a class that's currently being
1304 CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl();
1305 return Class && Class->isBeingDefined();
1308 /// Parse construction of a specified type.
1309 /// Can be interpreted either as function-style casting ("int(x)")
1310 /// or class type construction ("ClassType(x,y,z)")
1311 /// or creation of a value-initialized type ("int()").
1313 Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep,
1314 SourceLocation LParenOrBraceLoc,
1316 SourceLocation RParenOrBraceLoc,
1317 bool ListInitialization) {
1321 TypeSourceInfo *TInfo;
1322 QualType Ty = GetTypeFromParser(TypeRep, &TInfo);
1324 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation());
1326 auto Result = BuildCXXTypeConstructExpr(TInfo, LParenOrBraceLoc, exprs,
1327 RParenOrBraceLoc, ListInitialization);
1328 // Avoid creating a non-type-dependent expression that contains typos.
1329 // Non-type-dependent expressions are liable to be discarded without
1330 // checking for embedded typos.
1331 if (!Result.isInvalid() && Result.get()->isInstantiationDependent() &&
1332 !Result.get()->isTypeDependent())
1333 Result = CorrectDelayedTyposInExpr(Result.get());
1338 Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo,
1339 SourceLocation LParenOrBraceLoc,
1341 SourceLocation RParenOrBraceLoc,
1342 bool ListInitialization) {
1343 QualType Ty = TInfo->getType();
1344 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc();
1346 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(Exprs)) {
1347 // FIXME: CXXUnresolvedConstructExpr does not model list-initialization
1348 // directly. We work around this by dropping the locations of the braces.
1349 SourceRange Locs = ListInitialization
1351 : SourceRange(LParenOrBraceLoc, RParenOrBraceLoc);
1352 return CXXUnresolvedConstructExpr::Create(Context, TInfo, Locs.getBegin(),
1353 Exprs, Locs.getEnd());
1356 assert((!ListInitialization ||
1357 (Exprs.size() == 1 && isa<InitListExpr>(Exprs[0]))) &&
1358 "List initialization must have initializer list as expression.");
1359 SourceRange FullRange = SourceRange(TyBeginLoc, RParenOrBraceLoc);
1361 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo);
1362 InitializationKind Kind =
1364 ? ListInitialization
1365 ? InitializationKind::CreateDirectList(
1366 TyBeginLoc, LParenOrBraceLoc, RParenOrBraceLoc)
1367 : InitializationKind::CreateDirect(TyBeginLoc, LParenOrBraceLoc,
1369 : InitializationKind::CreateValue(TyBeginLoc, LParenOrBraceLoc,
1372 // C++1z [expr.type.conv]p1:
1373 // If the type is a placeholder for a deduced class type, [...perform class
1374 // template argument deduction...]
1375 DeducedType *Deduced = Ty->getContainedDeducedType();
1376 if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
1377 Ty = DeduceTemplateSpecializationFromInitializer(TInfo, Entity,
1381 Entity = InitializedEntity::InitializeTemporary(TInfo, Ty);
1384 // C++ [expr.type.conv]p1:
1385 // If the expression list is a parenthesized single expression, the type
1386 // conversion expression is equivalent (in definedness, and if defined in
1387 // meaning) to the corresponding cast expression.
1388 if (Exprs.size() == 1 && !ListInitialization &&
1389 !isa<InitListExpr>(Exprs[0])) {
1390 Expr *Arg = Exprs[0];
1391 return BuildCXXFunctionalCastExpr(TInfo, Ty, LParenOrBraceLoc, Arg,
1395 // For an expression of the form T(), T shall not be an array type.
1396 QualType ElemTy = Ty;
1397 if (Ty->isArrayType()) {
1398 if (!ListInitialization)
1399 return ExprError(Diag(TyBeginLoc, diag::err_value_init_for_array_type)
1401 ElemTy = Context.getBaseElementType(Ty);
1404 // There doesn't seem to be an explicit rule against this but sanity demands
1405 // we only construct objects with object types.
1406 if (Ty->isFunctionType())
1407 return ExprError(Diag(TyBeginLoc, diag::err_init_for_function_type)
1408 << Ty << FullRange);
1410 // C++17 [expr.type.conv]p2:
1411 // If the type is cv void and the initializer is (), the expression is a
1412 // prvalue of the specified type that performs no initialization.
1413 if (!Ty->isVoidType() &&
1414 RequireCompleteType(TyBeginLoc, ElemTy,
1415 diag::err_invalid_incomplete_type_use, FullRange))
1418 // Otherwise, the expression is a prvalue of the specified type whose
1419 // result object is direct-initialized (11.6) with the initializer.
1420 InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
1421 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Exprs);
1423 if (Result.isInvalid())
1426 Expr *Inner = Result.get();
1427 if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Inner))
1428 Inner = BTE->getSubExpr();
1429 if (!isa<CXXTemporaryObjectExpr>(Inner) &&
1430 !isa<CXXScalarValueInitExpr>(Inner)) {
1431 // If we created a CXXTemporaryObjectExpr, that node also represents the
1432 // functional cast. Otherwise, create an explicit cast to represent
1433 // the syntactic form of a functional-style cast that was used here.
1435 // FIXME: Creating a CXXFunctionalCastExpr around a CXXConstructExpr
1436 // would give a more consistent AST representation than using a
1437 // CXXTemporaryObjectExpr. It's also weird that the functional cast
1438 // is sometimes handled by initialization and sometimes not.
1439 QualType ResultType = Result.get()->getType();
1440 SourceRange Locs = ListInitialization
1442 : SourceRange(LParenOrBraceLoc, RParenOrBraceLoc);
1443 Result = CXXFunctionalCastExpr::Create(
1444 Context, ResultType, Expr::getValueKindForType(Ty), TInfo, CK_NoOp,
1445 Result.get(), /*Path=*/nullptr, Locs.getBegin(), Locs.getEnd());
1451 /// Determine whether the given function is a non-placement
1452 /// deallocation function.
1453 static bool isNonPlacementDeallocationFunction(Sema &S, FunctionDecl *FD) {
1454 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD))
1455 return Method->isUsualDeallocationFunction();
1457 if (FD->getOverloadedOperator() != OO_Delete &&
1458 FD->getOverloadedOperator() != OO_Array_Delete)
1461 unsigned UsualParams = 1;
1463 if (S.getLangOpts().SizedDeallocation && UsualParams < FD->getNumParams() &&
1464 S.Context.hasSameUnqualifiedType(
1465 FD->getParamDecl(UsualParams)->getType(),
1466 S.Context.getSizeType()))
1469 if (S.getLangOpts().AlignedAllocation && UsualParams < FD->getNumParams() &&
1470 S.Context.hasSameUnqualifiedType(
1471 FD->getParamDecl(UsualParams)->getType(),
1472 S.Context.getTypeDeclType(S.getStdAlignValT())))
1475 return UsualParams == FD->getNumParams();
1479 struct UsualDeallocFnInfo {
1480 UsualDeallocFnInfo() : Found(), FD(nullptr) {}
1481 UsualDeallocFnInfo(Sema &S, DeclAccessPair Found)
1482 : Found(Found), FD(dyn_cast<FunctionDecl>(Found->getUnderlyingDecl())),
1483 Destroying(false), HasSizeT(false), HasAlignValT(false),
1484 CUDAPref(Sema::CFP_Native) {
1485 // A function template declaration is never a usual deallocation function.
1488 unsigned NumBaseParams = 1;
1489 if (FD->isDestroyingOperatorDelete()) {
1493 if (FD->getNumParams() == NumBaseParams + 2)
1494 HasAlignValT = HasSizeT = true;
1495 else if (FD->getNumParams() == NumBaseParams + 1) {
1496 HasSizeT = FD->getParamDecl(NumBaseParams)->getType()->isIntegerType();
1497 HasAlignValT = !HasSizeT;
1500 // In CUDA, determine how much we'd like / dislike to call this.
1501 if (S.getLangOpts().CUDA)
1502 if (auto *Caller = dyn_cast<FunctionDecl>(S.CurContext))
1503 CUDAPref = S.IdentifyCUDAPreference(Caller, FD);
1506 explicit operator bool() const { return FD; }
1508 bool isBetterThan(const UsualDeallocFnInfo &Other, bool WantSize,
1509 bool WantAlign) const {
1511 // A destroying operator delete is preferred over a non-destroying
1513 if (Destroying != Other.Destroying)
1516 // C++17 [expr.delete]p10:
1517 // If the type has new-extended alignment, a function with a parameter
1518 // of type std::align_val_t is preferred; otherwise a function without
1519 // such a parameter is preferred
1520 if (HasAlignValT != Other.HasAlignValT)
1521 return HasAlignValT == WantAlign;
1523 if (HasSizeT != Other.HasSizeT)
1524 return HasSizeT == WantSize;
1526 // Use CUDA call preference as a tiebreaker.
1527 return CUDAPref > Other.CUDAPref;
1530 DeclAccessPair Found;
1532 bool Destroying, HasSizeT, HasAlignValT;
1533 Sema::CUDAFunctionPreference CUDAPref;
1537 /// Determine whether a type has new-extended alignment. This may be called when
1538 /// the type is incomplete (for a delete-expression with an incomplete pointee
1539 /// type), in which case it will conservatively return false if the alignment is
1541 static bool hasNewExtendedAlignment(Sema &S, QualType AllocType) {
1542 return S.getLangOpts().AlignedAllocation &&
1543 S.getASTContext().getTypeAlignIfKnown(AllocType) >
1544 S.getASTContext().getTargetInfo().getNewAlign();
1547 /// Select the correct "usual" deallocation function to use from a selection of
1548 /// deallocation functions (either global or class-scope).
1549 static UsualDeallocFnInfo resolveDeallocationOverload(
1550 Sema &S, LookupResult &R, bool WantSize, bool WantAlign,
1551 llvm::SmallVectorImpl<UsualDeallocFnInfo> *BestFns = nullptr) {
1552 UsualDeallocFnInfo Best;
1554 for (auto I = R.begin(), E = R.end(); I != E; ++I) {
1555 UsualDeallocFnInfo Info(S, I.getPair());
1556 if (!Info || !isNonPlacementDeallocationFunction(S, Info.FD) ||
1557 Info.CUDAPref == Sema::CFP_Never)
1563 BestFns->push_back(Info);
1567 if (Best.isBetterThan(Info, WantSize, WantAlign))
1570 // If more than one preferred function is found, all non-preferred
1571 // functions are eliminated from further consideration.
1572 if (BestFns && Info.isBetterThan(Best, WantSize, WantAlign))
1577 BestFns->push_back(Info);
1583 /// Determine whether a given type is a class for which 'delete[]' would call
1584 /// a member 'operator delete[]' with a 'size_t' parameter. This implies that
1585 /// we need to store the array size (even if the type is
1586 /// trivially-destructible).
1587 static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc,
1588 QualType allocType) {
1589 const RecordType *record =
1590 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>();
1591 if (!record) return false;
1593 // Try to find an operator delete[] in class scope.
1595 DeclarationName deleteName =
1596 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete);
1597 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName);
1598 S.LookupQualifiedName(ops, record->getDecl());
1600 // We're just doing this for information.
1601 ops.suppressDiagnostics();
1603 // Very likely: there's no operator delete[].
1604 if (ops.empty()) return false;
1606 // If it's ambiguous, it should be illegal to call operator delete[]
1607 // on this thing, so it doesn't matter if we allocate extra space or not.
1608 if (ops.isAmbiguous()) return false;
1610 // C++17 [expr.delete]p10:
1611 // If the deallocation functions have class scope, the one without a
1612 // parameter of type std::size_t is selected.
1613 auto Best = resolveDeallocationOverload(
1614 S, ops, /*WantSize*/false,
1615 /*WantAlign*/hasNewExtendedAlignment(S, allocType));
1616 return Best && Best.HasSizeT;
1619 /// Parsed a C++ 'new' expression (C++ 5.3.4).
1622 /// @code new (memory) int[size][4] @endcode
1624 /// @code ::new Foo(23, "hello") @endcode
1626 /// \param StartLoc The first location of the expression.
1627 /// \param UseGlobal True if 'new' was prefixed with '::'.
1628 /// \param PlacementLParen Opening paren of the placement arguments.
1629 /// \param PlacementArgs Placement new arguments.
1630 /// \param PlacementRParen Closing paren of the placement arguments.
1631 /// \param TypeIdParens If the type is in parens, the source range.
1632 /// \param D The type to be allocated, as well as array dimensions.
1633 /// \param Initializer The initializing expression or initializer-list, or null
1634 /// if there is none.
1636 Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
1637 SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
1638 SourceLocation PlacementRParen, SourceRange TypeIdParens,
1639 Declarator &D, Expr *Initializer) {
1640 Expr *ArraySize = nullptr;
1641 // If the specified type is an array, unwrap it and save the expression.
1642 if (D.getNumTypeObjects() > 0 &&
1643 D.getTypeObject(0).Kind == DeclaratorChunk::Array) {
1644 DeclaratorChunk &Chunk = D.getTypeObject(0);
1645 if (D.getDeclSpec().hasAutoTypeSpec())
1646 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto)
1647 << D.getSourceRange());
1648 if (Chunk.Arr.hasStatic)
1649 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
1650 << D.getSourceRange());
1651 if (!Chunk.Arr.NumElts)
1652 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
1653 << D.getSourceRange());
1655 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
1656 D.DropFirstTypeObject();
1659 // Every dimension shall be of constant size.
1661 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
1662 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array)
1665 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr;
1666 if (Expr *NumElts = (Expr *)Array.NumElts) {
1667 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
1668 if (getLangOpts().CPlusPlus14) {
1669 // C++1y [expr.new]p6: Every constant-expression in a noptr-new-declarator
1670 // shall be a converted constant expression (5.19) of type std::size_t
1671 // and shall evaluate to a strictly positive value.
1672 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
1673 assert(IntWidth && "Builtin type of size 0?");
1674 llvm::APSInt Value(IntWidth);
1676 = CheckConvertedConstantExpression(NumElts, Context.getSizeType(), Value,
1681 = VerifyIntegerConstantExpression(NumElts, nullptr,
1682 diag::err_new_array_nonconst)
1692 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/nullptr);
1693 QualType AllocType = TInfo->getType();
1694 if (D.isInvalidType())
1697 SourceRange DirectInitRange;
1698 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer))
1699 DirectInitRange = List->getSourceRange();
1701 return BuildCXXNew(SourceRange(StartLoc, D.getLocEnd()), UseGlobal,
1713 static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style,
1717 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init))
1718 return PLE->getNumExprs() == 0;
1719 if (isa<ImplicitValueInitExpr>(Init))
1721 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init))
1722 return !CCE->isListInitialization() &&
1723 CCE->getConstructor()->isDefaultConstructor();
1724 else if (Style == CXXNewExpr::ListInit) {
1725 assert(isa<InitListExpr>(Init) &&
1726 "Shouldn't create list CXXConstructExprs for arrays.");
1732 // Emit a diagnostic if an aligned allocation/deallocation function that is not
1733 // implemented in the standard library is selected.
1734 static void diagnoseUnavailableAlignedAllocation(const FunctionDecl &FD,
1735 SourceLocation Loc, bool IsDelete,
1737 if (!S.getLangOpts().AlignedAllocationUnavailable)
1740 // Return if there is a definition.
1744 bool IsAligned = false;
1745 if (FD.isReplaceableGlobalAllocationFunction(&IsAligned) && IsAligned) {
1746 const llvm::Triple &T = S.getASTContext().getTargetInfo().getTriple();
1747 StringRef OSName = AvailabilityAttr::getPlatformNameSourceSpelling(
1748 S.getASTContext().getTargetInfo().getPlatformName());
1750 S.Diag(Loc, diag::err_aligned_allocation_unavailable)
1751 << IsDelete << FD.getType().getAsString() << OSName
1752 << alignedAllocMinVersion(T.getOS()).getAsString();
1753 S.Diag(Loc, diag::note_silence_unligned_allocation_unavailable);
1758 Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
1759 SourceLocation PlacementLParen,
1760 MultiExprArg PlacementArgs,
1761 SourceLocation PlacementRParen,
1762 SourceRange TypeIdParens,
1764 TypeSourceInfo *AllocTypeInfo,
1766 SourceRange DirectInitRange,
1767 Expr *Initializer) {
1768 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange();
1769 SourceLocation StartLoc = Range.getBegin();
1771 CXXNewExpr::InitializationStyle initStyle;
1772 if (DirectInitRange.isValid()) {
1773 assert(Initializer && "Have parens but no initializer.");
1774 initStyle = CXXNewExpr::CallInit;
1775 } else if (Initializer && isa<InitListExpr>(Initializer))
1776 initStyle = CXXNewExpr::ListInit;
1778 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) ||
1779 isa<CXXConstructExpr>(Initializer)) &&
1780 "Initializer expression that cannot have been implicitly created.");
1781 initStyle = CXXNewExpr::NoInit;
1784 Expr **Inits = &Initializer;
1785 unsigned NumInits = Initializer ? 1 : 0;
1786 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) {
1787 assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init");
1788 Inits = List->getExprs();
1789 NumInits = List->getNumExprs();
1792 // C++11 [expr.new]p15:
1793 // A new-expression that creates an object of type T initializes that
1794 // object as follows:
1795 InitializationKind Kind
1796 // - If the new-initializer is omitted, the object is default-
1797 // initialized (8.5); if no initialization is performed,
1798 // the object has indeterminate value
1799 = initStyle == CXXNewExpr::NoInit
1800 ? InitializationKind::CreateDefault(TypeRange.getBegin())
1801 // - Otherwise, the new-initializer is interpreted according to the
1802 // initialization rules of 8.5 for direct-initialization.
1803 : initStyle == CXXNewExpr::ListInit
1804 ? InitializationKind::CreateDirectList(TypeRange.getBegin(),
1805 Initializer->getLocStart(),
1806 Initializer->getLocEnd())
1807 : InitializationKind::CreateDirect(TypeRange.getBegin(),
1808 DirectInitRange.getBegin(),
1809 DirectInitRange.getEnd());
1811 // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
1812 auto *Deduced = AllocType->getContainedDeducedType();
1813 if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
1815 return ExprError(Diag(ArraySize->getExprLoc(),
1816 diag::err_deduced_class_template_compound_type)
1817 << /*array*/ 2 << ArraySize->getSourceRange());
1819 InitializedEntity Entity
1820 = InitializedEntity::InitializeNew(StartLoc, AllocType);
1821 AllocType = DeduceTemplateSpecializationFromInitializer(
1822 AllocTypeInfo, Entity, Kind, MultiExprArg(Inits, NumInits));
1823 if (AllocType.isNull())
1825 } else if (Deduced) {
1826 bool Braced = (initStyle == CXXNewExpr::ListInit);
1827 if (NumInits == 1) {
1828 if (auto p = dyn_cast_or_null<InitListExpr>(Inits[0])) {
1829 Inits = p->getInits();
1830 NumInits = p->getNumInits();
1835 if (initStyle == CXXNewExpr::NoInit || NumInits == 0)
1836 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg)
1837 << AllocType << TypeRange);
1839 Expr *FirstBad = Inits[1];
1840 return ExprError(Diag(FirstBad->getLocStart(),
1841 diag::err_auto_new_ctor_multiple_expressions)
1842 << AllocType << TypeRange);
1844 if (Braced && !getLangOpts().CPlusPlus17)
1845 Diag(Initializer->getLocStart(), diag::ext_auto_new_list_init)
1846 << AllocType << TypeRange;
1847 Expr *Deduce = Inits[0];
1848 QualType DeducedType;
1849 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed)
1850 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure)
1851 << AllocType << Deduce->getType()
1852 << TypeRange << Deduce->getSourceRange());
1853 if (DeducedType.isNull())
1855 AllocType = DeducedType;
1858 // Per C++0x [expr.new]p5, the type being constructed may be a
1859 // typedef of an array type.
1861 if (const ConstantArrayType *Array
1862 = Context.getAsConstantArrayType(AllocType)) {
1863 ArraySize = IntegerLiteral::Create(Context, Array->getSize(),
1864 Context.getSizeType(),
1865 TypeRange.getEnd());
1866 AllocType = Array->getElementType();
1870 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange))
1873 // In ARC, infer 'retaining' for the allocated
1874 if (getLangOpts().ObjCAutoRefCount &&
1875 AllocType.getObjCLifetime() == Qualifiers::OCL_None &&
1876 AllocType->isObjCLifetimeType()) {
1877 AllocType = Context.getLifetimeQualifiedType(AllocType,
1878 AllocType->getObjCARCImplicitLifetime());
1881 QualType ResultType = Context.getPointerType(AllocType);
1883 if (ArraySize && ArraySize->getType()->isNonOverloadPlaceholderType()) {
1884 ExprResult result = CheckPlaceholderExpr(ArraySize);
1885 if (result.isInvalid()) return ExprError();
1886 ArraySize = result.get();
1888 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have
1889 // integral or enumeration type with a non-negative value."
1890 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped
1891 // enumeration type, or a class type for which a single non-explicit
1892 // conversion function to integral or unscoped enumeration type exists.
1893 // C++1y [expr.new]p6: The expression [...] is implicitly converted to
1895 llvm::Optional<uint64_t> KnownArraySize;
1896 if (ArraySize && !ArraySize->isTypeDependent()) {
1897 ExprResult ConvertedSize;
1898 if (getLangOpts().CPlusPlus14) {
1899 assert(Context.getTargetInfo().getIntWidth() && "Builtin type of size 0?");
1901 ConvertedSize = PerformImplicitConversion(ArraySize, Context.getSizeType(),
1904 if (!ConvertedSize.isInvalid() &&
1905 ArraySize->getType()->getAs<RecordType>())
1906 // Diagnose the compatibility of this conversion.
1907 Diag(StartLoc, diag::warn_cxx98_compat_array_size_conversion)
1908 << ArraySize->getType() << 0 << "'size_t'";
1910 class SizeConvertDiagnoser : public ICEConvertDiagnoser {
1915 SizeConvertDiagnoser(Expr *ArraySize)
1916 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false, false, false),
1917 ArraySize(ArraySize) {}
1919 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
1920 QualType T) override {
1921 return S.Diag(Loc, diag::err_array_size_not_integral)
1922 << S.getLangOpts().CPlusPlus11 << T;
1925 SemaDiagnosticBuilder diagnoseIncomplete(
1926 Sema &S, SourceLocation Loc, QualType T) override {
1927 return S.Diag(Loc, diag::err_array_size_incomplete_type)
1928 << T << ArraySize->getSourceRange();
1931 SemaDiagnosticBuilder diagnoseExplicitConv(
1932 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
1933 return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy;
1936 SemaDiagnosticBuilder noteExplicitConv(
1937 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1938 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1939 << ConvTy->isEnumeralType() << ConvTy;
1942 SemaDiagnosticBuilder diagnoseAmbiguous(
1943 Sema &S, SourceLocation Loc, QualType T) override {
1944 return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T;
1947 SemaDiagnosticBuilder noteAmbiguous(
1948 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1949 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1950 << ConvTy->isEnumeralType() << ConvTy;
1953 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
1955 QualType ConvTy) override {
1957 S.getLangOpts().CPlusPlus11
1958 ? diag::warn_cxx98_compat_array_size_conversion
1959 : diag::ext_array_size_conversion)
1960 << T << ConvTy->isEnumeralType() << ConvTy;
1962 } SizeDiagnoser(ArraySize);
1964 ConvertedSize = PerformContextualImplicitConversion(StartLoc, ArraySize,
1967 if (ConvertedSize.isInvalid())
1970 ArraySize = ConvertedSize.get();
1971 QualType SizeType = ArraySize->getType();
1973 if (!SizeType->isIntegralOrUnscopedEnumerationType())
1976 // C++98 [expr.new]p7:
1977 // The expression in a direct-new-declarator shall have integral type
1978 // with a non-negative value.
1980 // Let's see if this is a constant < 0. If so, we reject it out of hand,
1981 // per CWG1464. Otherwise, if it's not a constant, we must have an
1982 // unparenthesized array type.
1983 if (!ArraySize->isValueDependent()) {
1985 // We've already performed any required implicit conversion to integer or
1986 // unscoped enumeration type.
1987 // FIXME: Per CWG1464, we are required to check the value prior to
1988 // converting to size_t. This will never find a negative array size in
1989 // C++14 onwards, because Value is always unsigned here!
1990 if (ArraySize->isIntegerConstantExpr(Value, Context)) {
1991 if (Value.isSigned() && Value.isNegative()) {
1992 return ExprError(Diag(ArraySize->getLocStart(),
1993 diag::err_typecheck_negative_array_size)
1994 << ArraySize->getSourceRange());
1997 if (!AllocType->isDependentType()) {
1998 unsigned ActiveSizeBits =
1999 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value);
2000 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context))
2001 return ExprError(Diag(ArraySize->getLocStart(),
2002 diag::err_array_too_large)
2003 << Value.toString(10)
2004 << ArraySize->getSourceRange());
2007 KnownArraySize = Value.getZExtValue();
2008 } else if (TypeIdParens.isValid()) {
2009 // Can't have dynamic array size when the type-id is in parentheses.
2010 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst)
2011 << ArraySize->getSourceRange()
2012 << FixItHint::CreateRemoval(TypeIdParens.getBegin())
2013 << FixItHint::CreateRemoval(TypeIdParens.getEnd());
2015 TypeIdParens = SourceRange();
2019 // Note that we do *not* convert the argument in any way. It can
2020 // be signed, larger than size_t, whatever.
2023 FunctionDecl *OperatorNew = nullptr;
2024 FunctionDecl *OperatorDelete = nullptr;
2025 unsigned Alignment =
2026 AllocType->isDependentType() ? 0 : Context.getTypeAlign(AllocType);
2027 unsigned NewAlignment = Context.getTargetInfo().getNewAlign();
2028 bool PassAlignment = getLangOpts().AlignedAllocation &&
2029 Alignment > NewAlignment;
2031 AllocationFunctionScope Scope = UseGlobal ? AFS_Global : AFS_Both;
2032 if (!AllocType->isDependentType() &&
2033 !Expr::hasAnyTypeDependentArguments(PlacementArgs) &&
2034 FindAllocationFunctions(StartLoc,
2035 SourceRange(PlacementLParen, PlacementRParen),
2036 Scope, Scope, AllocType, ArraySize, PassAlignment,
2037 PlacementArgs, OperatorNew, OperatorDelete))
2040 // If this is an array allocation, compute whether the usual array
2041 // deallocation function for the type has a size_t parameter.
2042 bool UsualArrayDeleteWantsSize = false;
2043 if (ArraySize && !AllocType->isDependentType())
2044 UsualArrayDeleteWantsSize =
2045 doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType);
2047 SmallVector<Expr *, 8> AllPlaceArgs;
2049 const FunctionProtoType *Proto =
2050 OperatorNew->getType()->getAs<FunctionProtoType>();
2051 VariadicCallType CallType = Proto->isVariadic() ? VariadicFunction
2052 : VariadicDoesNotApply;
2054 // We've already converted the placement args, just fill in any default
2055 // arguments. Skip the first parameter because we don't have a corresponding
2056 // argument. Skip the second parameter too if we're passing in the
2057 // alignment; we've already filled it in.
2058 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, Proto,
2059 PassAlignment ? 2 : 1, PlacementArgs,
2060 AllPlaceArgs, CallType))
2063 if (!AllPlaceArgs.empty())
2064 PlacementArgs = AllPlaceArgs;
2066 // FIXME: This is wrong: PlacementArgs misses out the first (size) argument.
2067 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, PlacementArgs);
2069 // FIXME: Missing call to CheckFunctionCall or equivalent
2071 // Warn if the type is over-aligned and is being allocated by (unaligned)
2072 // global operator new.
2073 if (PlacementArgs.empty() && !PassAlignment &&
2074 (OperatorNew->isImplicit() ||
2075 (OperatorNew->getLocStart().isValid() &&
2076 getSourceManager().isInSystemHeader(OperatorNew->getLocStart())))) {
2077 if (Alignment > NewAlignment)
2078 Diag(StartLoc, diag::warn_overaligned_type)
2080 << unsigned(Alignment / Context.getCharWidth())
2081 << unsigned(NewAlignment / Context.getCharWidth());
2085 // Array 'new' can't have any initializers except empty parentheses.
2086 // Initializer lists are also allowed, in C++11. Rely on the parser for the
2087 // dialect distinction.
2088 if (ArraySize && !isLegalArrayNewInitializer(initStyle, Initializer)) {
2089 SourceRange InitRange(Inits[0]->getLocStart(),
2090 Inits[NumInits - 1]->getLocEnd());
2091 Diag(StartLoc, diag::err_new_array_init_args) << InitRange;
2095 // If we can perform the initialization, and we've not already done so,
2097 if (!AllocType->isDependentType() &&
2098 !Expr::hasAnyTypeDependentArguments(
2099 llvm::makeArrayRef(Inits, NumInits))) {
2100 // The type we initialize is the complete type, including the array bound.
2103 InitType = Context.getConstantArrayType(
2104 AllocType, llvm::APInt(Context.getTypeSize(Context.getSizeType()),
2106 ArrayType::Normal, 0);
2109 Context.getIncompleteArrayType(AllocType, ArrayType::Normal, 0);
2111 InitType = AllocType;
2113 InitializedEntity Entity
2114 = InitializedEntity::InitializeNew(StartLoc, InitType);
2115 InitializationSequence InitSeq(*this, Entity, Kind,
2116 MultiExprArg(Inits, NumInits));
2117 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind,
2118 MultiExprArg(Inits, NumInits));
2119 if (FullInit.isInvalid())
2122 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because
2123 // we don't want the initialized object to be destructed.
2124 // FIXME: We should not create these in the first place.
2125 if (CXXBindTemporaryExpr *Binder =
2126 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get()))
2127 FullInit = Binder->getSubExpr();
2129 Initializer = FullInit.get();
2132 // Mark the new and delete operators as referenced.
2134 if (DiagnoseUseOfDecl(OperatorNew, StartLoc))
2136 MarkFunctionReferenced(StartLoc, OperatorNew);
2137 diagnoseUnavailableAlignedAllocation(*OperatorNew, StartLoc, false, *this);
2139 if (OperatorDelete) {
2140 if (DiagnoseUseOfDecl(OperatorDelete, StartLoc))
2142 MarkFunctionReferenced(StartLoc, OperatorDelete);
2143 diagnoseUnavailableAlignedAllocation(*OperatorDelete, StartLoc, true, *this);
2146 // C++0x [expr.new]p17:
2147 // If the new expression creates an array of objects of class type,
2148 // access and ambiguity control are done for the destructor.
2149 QualType BaseAllocType = Context.getBaseElementType(AllocType);
2150 if (ArraySize && !BaseAllocType->isDependentType()) {
2151 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) {
2152 if (CXXDestructorDecl *dtor = LookupDestructor(
2153 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) {
2154 MarkFunctionReferenced(StartLoc, dtor);
2155 CheckDestructorAccess(StartLoc, dtor,
2156 PDiag(diag::err_access_dtor)
2158 if (DiagnoseUseOfDecl(dtor, StartLoc))
2164 return new (Context)
2165 CXXNewExpr(Context, UseGlobal, OperatorNew, OperatorDelete, PassAlignment,
2166 UsualArrayDeleteWantsSize, PlacementArgs, TypeIdParens,
2167 ArraySize, initStyle, Initializer, ResultType, AllocTypeInfo,
2168 Range, DirectInitRange);
2171 /// Checks that a type is suitable as the allocated type
2172 /// in a new-expression.
2173 bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc,
2175 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
2176 // abstract class type or array thereof.
2177 if (AllocType->isFunctionType())
2178 return Diag(Loc, diag::err_bad_new_type)
2179 << AllocType << 0 << R;
2180 else if (AllocType->isReferenceType())
2181 return Diag(Loc, diag::err_bad_new_type)
2182 << AllocType << 1 << R;
2183 else if (!AllocType->isDependentType() &&
2184 RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R))
2186 else if (RequireNonAbstractType(Loc, AllocType,
2187 diag::err_allocation_of_abstract_type))
2189 else if (AllocType->isVariablyModifiedType())
2190 return Diag(Loc, diag::err_variably_modified_new_type)
2192 else if (AllocType.getAddressSpace() != LangAS::Default &&
2193 !getLangOpts().OpenCLCPlusPlus)
2194 return Diag(Loc, diag::err_address_space_qualified_new)
2195 << AllocType.getUnqualifiedType()
2196 << AllocType.getQualifiers().getAddressSpaceAttributePrintValue();
2197 else if (getLangOpts().ObjCAutoRefCount) {
2198 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) {
2199 QualType BaseAllocType = Context.getBaseElementType(AT);
2200 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None &&
2201 BaseAllocType->isObjCLifetimeType())
2202 return Diag(Loc, diag::err_arc_new_array_without_ownership)
2210 static bool resolveAllocationOverload(
2211 Sema &S, LookupResult &R, SourceRange Range, SmallVectorImpl<Expr *> &Args,
2212 bool &PassAlignment, FunctionDecl *&Operator,
2213 OverloadCandidateSet *AlignedCandidates, Expr *AlignArg, bool Diagnose) {
2214 OverloadCandidateSet Candidates(R.getNameLoc(),
2215 OverloadCandidateSet::CSK_Normal);
2216 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
2217 Alloc != AllocEnd; ++Alloc) {
2218 // Even member operator new/delete are implicitly treated as
2219 // static, so don't use AddMemberCandidate.
2220 NamedDecl *D = (*Alloc)->getUnderlyingDecl();
2222 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
2223 S.AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(),
2224 /*ExplicitTemplateArgs=*/nullptr, Args,
2226 /*SuppressUserConversions=*/false);
2230 FunctionDecl *Fn = cast<FunctionDecl>(D);
2231 S.AddOverloadCandidate(Fn, Alloc.getPair(), Args, Candidates,
2232 /*SuppressUserConversions=*/false);
2235 // Do the resolution.
2236 OverloadCandidateSet::iterator Best;
2237 switch (Candidates.BestViableFunction(S, R.getNameLoc(), Best)) {
2240 FunctionDecl *FnDecl = Best->Function;
2241 if (S.CheckAllocationAccess(R.getNameLoc(), Range, R.getNamingClass(),
2242 Best->FoundDecl) == Sema::AR_inaccessible)
2249 case OR_No_Viable_Function:
2250 // C++17 [expr.new]p13:
2251 // If no matching function is found and the allocated object type has
2252 // new-extended alignment, the alignment argument is removed from the
2253 // argument list, and overload resolution is performed again.
2254 if (PassAlignment) {
2255 PassAlignment = false;
2257 Args.erase(Args.begin() + 1);
2258 return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2259 Operator, &Candidates, AlignArg,
2263 // MSVC will fall back on trying to find a matching global operator new
2264 // if operator new[] cannot be found. Also, MSVC will leak by not
2265 // generating a call to operator delete or operator delete[], but we
2266 // will not replicate that bug.
2267 // FIXME: Find out how this interacts with the std::align_val_t fallback
2268 // once MSVC implements it.
2269 if (R.getLookupName().getCXXOverloadedOperator() == OO_Array_New &&
2270 S.Context.getLangOpts().MSVCCompat) {
2272 R.setLookupName(S.Context.DeclarationNames.getCXXOperatorName(OO_New));
2273 S.LookupQualifiedName(R, S.Context.getTranslationUnitDecl());
2274 // FIXME: This will give bad diagnostics pointing at the wrong functions.
2275 return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2276 Operator, /*Candidates=*/nullptr,
2277 /*AlignArg=*/nullptr, Diagnose);
2281 S.Diag(R.getNameLoc(), diag::err_ovl_no_viable_function_in_call)
2282 << R.getLookupName() << Range;
2284 // If we have aligned candidates, only note the align_val_t candidates
2285 // from AlignedCandidates and the non-align_val_t candidates from
2287 if (AlignedCandidates) {
2288 auto IsAligned = [](OverloadCandidate &C) {
2289 return C.Function->getNumParams() > 1 &&
2290 C.Function->getParamDecl(1)->getType()->isAlignValT();
2292 auto IsUnaligned = [&](OverloadCandidate &C) { return !IsAligned(C); };
2294 // This was an overaligned allocation, so list the aligned candidates
2296 Args.insert(Args.begin() + 1, AlignArg);
2297 AlignedCandidates->NoteCandidates(S, OCD_AllCandidates, Args, "",
2298 R.getNameLoc(), IsAligned);
2299 Args.erase(Args.begin() + 1);
2300 Candidates.NoteCandidates(S, OCD_AllCandidates, Args, "", R.getNameLoc(),
2303 Candidates.NoteCandidates(S, OCD_AllCandidates, Args);
2310 S.Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call)
2311 << R.getLookupName() << Range;
2312 Candidates.NoteCandidates(S, OCD_ViableCandidates, Args);
2318 S.Diag(R.getNameLoc(), diag::err_ovl_deleted_call)
2319 << Best->Function->isDeleted() << R.getLookupName()
2320 << S.getDeletedOrUnavailableSuffix(Best->Function) << Range;
2321 Candidates.NoteCandidates(S, OCD_AllCandidates, Args);
2326 llvm_unreachable("Unreachable, bad result from BestViableFunction");
2329 bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
2330 AllocationFunctionScope NewScope,
2331 AllocationFunctionScope DeleteScope,
2332 QualType AllocType, bool IsArray,
2333 bool &PassAlignment, MultiExprArg PlaceArgs,
2334 FunctionDecl *&OperatorNew,
2335 FunctionDecl *&OperatorDelete,
2337 // --- Choosing an allocation function ---
2338 // C++ 5.3.4p8 - 14 & 18
2339 // 1) If looking in AFS_Global scope for allocation functions, only look in
2340 // the global scope. Else, if AFS_Class, only look in the scope of the
2341 // allocated class. If AFS_Both, look in both.
2342 // 2) If an array size is given, look for operator new[], else look for
2344 // 3) The first argument is always size_t. Append the arguments from the
2347 SmallVector<Expr*, 8> AllocArgs;
2348 AllocArgs.reserve((PassAlignment ? 2 : 1) + PlaceArgs.size());
2350 // We don't care about the actual value of these arguments.
2351 // FIXME: Should the Sema create the expression and embed it in the syntax
2352 // tree? Or should the consumer just recalculate the value?
2353 // FIXME: Using a dummy value will interact poorly with attribute enable_if.
2354 IntegerLiteral Size(Context, llvm::APInt::getNullValue(
2355 Context.getTargetInfo().getPointerWidth(0)),
2356 Context.getSizeType(),
2358 AllocArgs.push_back(&Size);
2360 QualType AlignValT = Context.VoidTy;
2361 if (PassAlignment) {
2362 DeclareGlobalNewDelete();
2363 AlignValT = Context.getTypeDeclType(getStdAlignValT());
2365 CXXScalarValueInitExpr Align(AlignValT, nullptr, SourceLocation());
2367 AllocArgs.push_back(&Align);
2369 AllocArgs.insert(AllocArgs.end(), PlaceArgs.begin(), PlaceArgs.end());
2371 // C++ [expr.new]p8:
2372 // If the allocated type is a non-array type, the allocation
2373 // function's name is operator new and the deallocation function's
2374 // name is operator delete. If the allocated type is an array
2375 // type, the allocation function's name is operator new[] and the
2376 // deallocation function's name is operator delete[].
2377 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName(
2378 IsArray ? OO_Array_New : OO_New);
2380 QualType AllocElemType = Context.getBaseElementType(AllocType);
2382 // Find the allocation function.
2384 LookupResult R(*this, NewName, StartLoc, LookupOrdinaryName);
2386 // C++1z [expr.new]p9:
2387 // If the new-expression begins with a unary :: operator, the allocation
2388 // function's name is looked up in the global scope. Otherwise, if the
2389 // allocated type is a class type T or array thereof, the allocation
2390 // function's name is looked up in the scope of T.
2391 if (AllocElemType->isRecordType() && NewScope != AFS_Global)
2392 LookupQualifiedName(R, AllocElemType->getAsCXXRecordDecl());
2394 // We can see ambiguity here if the allocation function is found in
2395 // multiple base classes.
2396 if (R.isAmbiguous())
2399 // If this lookup fails to find the name, or if the allocated type is not
2400 // a class type, the allocation function's name is looked up in the
2403 if (NewScope == AFS_Class)
2406 LookupQualifiedName(R, Context.getTranslationUnitDecl());
2409 if (getLangOpts().OpenCLCPlusPlus && R.empty()) {
2410 Diag(StartLoc, diag::err_openclcxx_not_supported) << "default new";
2414 assert(!R.empty() && "implicitly declared allocation functions not found");
2415 assert(!R.isAmbiguous() && "global allocation functions are ambiguous");
2417 // We do our own custom access checks below.
2418 R.suppressDiagnostics();
2420 if (resolveAllocationOverload(*this, R, Range, AllocArgs, PassAlignment,
2421 OperatorNew, /*Candidates=*/nullptr,
2422 /*AlignArg=*/nullptr, Diagnose))
2426 // We don't need an operator delete if we're running under -fno-exceptions.
2427 if (!getLangOpts().Exceptions) {
2428 OperatorDelete = nullptr;
2432 // Note, the name of OperatorNew might have been changed from array to
2433 // non-array by resolveAllocationOverload.
2434 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
2435 OperatorNew->getDeclName().getCXXOverloadedOperator() == OO_Array_New
2439 // C++ [expr.new]p19:
2441 // If the new-expression begins with a unary :: operator, the
2442 // deallocation function's name is looked up in the global
2443 // scope. Otherwise, if the allocated type is a class type T or an
2444 // array thereof, the deallocation function's name is looked up in
2445 // the scope of T. If this lookup fails to find the name, or if
2446 // the allocated type is not a class type or array thereof, the
2447 // deallocation function's name is looked up in the global scope.
2448 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName);
2449 if (AllocElemType->isRecordType() && DeleteScope != AFS_Global) {
2451 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl());
2452 LookupQualifiedName(FoundDelete, RD);
2454 if (FoundDelete.isAmbiguous())
2455 return true; // FIXME: clean up expressions?
2457 bool FoundGlobalDelete = FoundDelete.empty();
2458 if (FoundDelete.empty()) {
2459 if (DeleteScope == AFS_Class)
2462 DeclareGlobalNewDelete();
2463 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2466 FoundDelete.suppressDiagnostics();
2468 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches;
2470 // Whether we're looking for a placement operator delete is dictated
2471 // by whether we selected a placement operator new, not by whether
2472 // we had explicit placement arguments. This matters for things like
2473 // struct A { void *operator new(size_t, int = 0); ... };
2476 // We don't have any definition for what a "placement allocation function"
2477 // is, but we assume it's any allocation function whose
2478 // parameter-declaration-clause is anything other than (size_t).
2480 // FIXME: Should (size_t, std::align_val_t) also be considered non-placement?
2481 // This affects whether an exception from the constructor of an overaligned
2482 // type uses the sized or non-sized form of aligned operator delete.
2483 bool isPlacementNew = !PlaceArgs.empty() || OperatorNew->param_size() != 1 ||
2484 OperatorNew->isVariadic();
2486 if (isPlacementNew) {
2487 // C++ [expr.new]p20:
2488 // A declaration of a placement deallocation function matches the
2489 // declaration of a placement allocation function if it has the
2490 // same number of parameters and, after parameter transformations
2491 // (8.3.5), all parameter types except the first are
2494 // To perform this comparison, we compute the function type that
2495 // the deallocation function should have, and use that type both
2496 // for template argument deduction and for comparison purposes.
2497 QualType ExpectedFunctionType;
2499 const FunctionProtoType *Proto
2500 = OperatorNew->getType()->getAs<FunctionProtoType>();
2502 SmallVector<QualType, 4> ArgTypes;
2503 ArgTypes.push_back(Context.VoidPtrTy);
2504 for (unsigned I = 1, N = Proto->getNumParams(); I < N; ++I)
2505 ArgTypes.push_back(Proto->getParamType(I));
2507 FunctionProtoType::ExtProtoInfo EPI;
2508 // FIXME: This is not part of the standard's rule.
2509 EPI.Variadic = Proto->isVariadic();
2511 ExpectedFunctionType
2512 = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI);
2515 for (LookupResult::iterator D = FoundDelete.begin(),
2516 DEnd = FoundDelete.end();
2518 FunctionDecl *Fn = nullptr;
2519 if (FunctionTemplateDecl *FnTmpl =
2520 dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) {
2521 // Perform template argument deduction to try to match the
2522 // expected function type.
2523 TemplateDeductionInfo Info(StartLoc);
2524 if (DeduceTemplateArguments(FnTmpl, nullptr, ExpectedFunctionType, Fn,
2528 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl());
2530 if (Context.hasSameType(adjustCCAndNoReturn(Fn->getType(),
2531 ExpectedFunctionType,
2532 /*AdjustExcpetionSpec*/true),
2533 ExpectedFunctionType))
2534 Matches.push_back(std::make_pair(D.getPair(), Fn));
2537 if (getLangOpts().CUDA)
2538 EraseUnwantedCUDAMatches(dyn_cast<FunctionDecl>(CurContext), Matches);
2540 // C++1y [expr.new]p22:
2541 // For a non-placement allocation function, the normal deallocation
2542 // function lookup is used
2544 // Per [expr.delete]p10, this lookup prefers a member operator delete
2545 // without a size_t argument, but prefers a non-member operator delete
2546 // with a size_t where possible (which it always is in this case).
2547 llvm::SmallVector<UsualDeallocFnInfo, 4> BestDeallocFns;
2548 UsualDeallocFnInfo Selected = resolveDeallocationOverload(
2549 *this, FoundDelete, /*WantSize*/ FoundGlobalDelete,
2550 /*WantAlign*/ hasNewExtendedAlignment(*this, AllocElemType),
2553 Matches.push_back(std::make_pair(Selected.Found, Selected.FD));
2555 // If we failed to select an operator, all remaining functions are viable
2557 for (auto Fn : BestDeallocFns)
2558 Matches.push_back(std::make_pair(Fn.Found, Fn.FD));
2562 // C++ [expr.new]p20:
2563 // [...] If the lookup finds a single matching deallocation
2564 // function, that function will be called; otherwise, no
2565 // deallocation function will be called.
2566 if (Matches.size() == 1) {
2567 OperatorDelete = Matches[0].second;
2569 // C++1z [expr.new]p23:
2570 // If the lookup finds a usual deallocation function (3.7.4.2)
2571 // with a parameter of type std::size_t and that function, considered
2572 // as a placement deallocation function, would have been
2573 // selected as a match for the allocation function, the program
2575 if (getLangOpts().CPlusPlus11 && isPlacementNew &&
2576 isNonPlacementDeallocationFunction(*this, OperatorDelete)) {
2577 UsualDeallocFnInfo Info(*this,
2578 DeclAccessPair::make(OperatorDelete, AS_public));
2579 // Core issue, per mail to core reflector, 2016-10-09:
2580 // If this is a member operator delete, and there is a corresponding
2581 // non-sized member operator delete, this isn't /really/ a sized
2582 // deallocation function, it just happens to have a size_t parameter.
2583 bool IsSizedDelete = Info.HasSizeT;
2584 if (IsSizedDelete && !FoundGlobalDelete) {
2585 auto NonSizedDelete =
2586 resolveDeallocationOverload(*this, FoundDelete, /*WantSize*/false,
2587 /*WantAlign*/Info.HasAlignValT);
2588 if (NonSizedDelete && !NonSizedDelete.HasSizeT &&
2589 NonSizedDelete.HasAlignValT == Info.HasAlignValT)
2590 IsSizedDelete = false;
2593 if (IsSizedDelete) {
2594 SourceRange R = PlaceArgs.empty()
2596 : SourceRange(PlaceArgs.front()->getLocStart(),
2597 PlaceArgs.back()->getLocEnd());
2598 Diag(StartLoc, diag::err_placement_new_non_placement_delete) << R;
2599 if (!OperatorDelete->isImplicit())
2600 Diag(OperatorDelete->getLocation(), diag::note_previous_decl)
2605 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(),
2607 } else if (!Matches.empty()) {
2608 // We found multiple suitable operators. Per [expr.new]p20, that means we
2609 // call no 'operator delete' function, but we should at least warn the user.
2610 // FIXME: Suppress this warning if the construction cannot throw.
2611 Diag(StartLoc, diag::warn_ambiguous_suitable_delete_function_found)
2612 << DeleteName << AllocElemType;
2614 for (auto &Match : Matches)
2615 Diag(Match.second->getLocation(),
2616 diag::note_member_declared_here) << DeleteName;
2622 /// DeclareGlobalNewDelete - Declare the global forms of operator new and
2623 /// delete. These are:
2626 /// void* operator new(std::size_t) throw(std::bad_alloc);
2627 /// void* operator new[](std::size_t) throw(std::bad_alloc);
2628 /// void operator delete(void *) throw();
2629 /// void operator delete[](void *) throw();
2631 /// void* operator new(std::size_t);
2632 /// void* operator new[](std::size_t);
2633 /// void operator delete(void *) noexcept;
2634 /// void operator delete[](void *) noexcept;
2636 /// void* operator new(std::size_t);
2637 /// void* operator new[](std::size_t);
2638 /// void operator delete(void *) noexcept;
2639 /// void operator delete[](void *) noexcept;
2640 /// void operator delete(void *, std::size_t) noexcept;
2641 /// void operator delete[](void *, std::size_t) noexcept;
2643 /// Note that the placement and nothrow forms of new are *not* implicitly
2644 /// declared. Their use requires including \<new\>.
2645 void Sema::DeclareGlobalNewDelete() {
2646 if (GlobalNewDeleteDeclared)
2649 // OpenCL C++ 1.0 s2.9: the implicitly declared new and delete operators
2650 // are not supported.
2651 if (getLangOpts().OpenCLCPlusPlus)
2654 // C++ [basic.std.dynamic]p2:
2655 // [...] The following allocation and deallocation functions (18.4) are
2656 // implicitly declared in global scope in each translation unit of a
2660 // void* operator new(std::size_t) throw(std::bad_alloc);
2661 // void* operator new[](std::size_t) throw(std::bad_alloc);
2662 // void operator delete(void*) throw();
2663 // void operator delete[](void*) throw();
2665 // void* operator new(std::size_t);
2666 // void* operator new[](std::size_t);
2667 // void operator delete(void*) noexcept;
2668 // void operator delete[](void*) noexcept;
2670 // void* operator new(std::size_t);
2671 // void* operator new[](std::size_t);
2672 // void operator delete(void*) noexcept;
2673 // void operator delete[](void*) noexcept;
2674 // void operator delete(void*, std::size_t) noexcept;
2675 // void operator delete[](void*, std::size_t) noexcept;
2677 // These implicit declarations introduce only the function names operator
2678 // new, operator new[], operator delete, operator delete[].
2680 // Here, we need to refer to std::bad_alloc, so we will implicitly declare
2681 // "std" or "bad_alloc" as necessary to form the exception specification.
2682 // However, we do not make these implicit declarations visible to name
2684 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) {
2685 // The "std::bad_alloc" class has not yet been declared, so build it
2687 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class,
2688 getOrCreateStdNamespace(),
2689 SourceLocation(), SourceLocation(),
2690 &PP.getIdentifierTable().get("bad_alloc"),
2692 getStdBadAlloc()->setImplicit(true);
2694 if (!StdAlignValT && getLangOpts().AlignedAllocation) {
2695 // The "std::align_val_t" enum class has not yet been declared, so build it
2697 auto *AlignValT = EnumDecl::Create(
2698 Context, getOrCreateStdNamespace(), SourceLocation(), SourceLocation(),
2699 &PP.getIdentifierTable().get("align_val_t"), nullptr, true, true, true);
2700 AlignValT->setIntegerType(Context.getSizeType());
2701 AlignValT->setPromotionType(Context.getSizeType());
2702 AlignValT->setImplicit(true);
2703 StdAlignValT = AlignValT;
2706 GlobalNewDeleteDeclared = true;
2708 QualType VoidPtr = Context.getPointerType(Context.VoidTy);
2709 QualType SizeT = Context.getSizeType();
2711 auto DeclareGlobalAllocationFunctions = [&](OverloadedOperatorKind Kind,
2712 QualType Return, QualType Param) {
2713 llvm::SmallVector<QualType, 3> Params;
2714 Params.push_back(Param);
2716 // Create up to four variants of the function (sized/aligned).
2717 bool HasSizedVariant = getLangOpts().SizedDeallocation &&
2718 (Kind == OO_Delete || Kind == OO_Array_Delete);
2719 bool HasAlignedVariant = getLangOpts().AlignedAllocation;
2721 int NumSizeVariants = (HasSizedVariant ? 2 : 1);
2722 int NumAlignVariants = (HasAlignedVariant ? 2 : 1);
2723 for (int Sized = 0; Sized < NumSizeVariants; ++Sized) {
2725 Params.push_back(SizeT);
2727 for (int Aligned = 0; Aligned < NumAlignVariants; ++Aligned) {
2729 Params.push_back(Context.getTypeDeclType(getStdAlignValT()));
2731 DeclareGlobalAllocationFunction(
2732 Context.DeclarationNames.getCXXOperatorName(Kind), Return, Params);
2740 DeclareGlobalAllocationFunctions(OO_New, VoidPtr, SizeT);
2741 DeclareGlobalAllocationFunctions(OO_Array_New, VoidPtr, SizeT);
2742 DeclareGlobalAllocationFunctions(OO_Delete, Context.VoidTy, VoidPtr);
2743 DeclareGlobalAllocationFunctions(OO_Array_Delete, Context.VoidTy, VoidPtr);
2746 /// DeclareGlobalAllocationFunction - Declares a single implicit global
2747 /// allocation function if it doesn't already exist.
2748 void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
2750 ArrayRef<QualType> Params) {
2751 DeclContext *GlobalCtx = Context.getTranslationUnitDecl();
2753 // Check if this function is already declared.
2754 DeclContext::lookup_result R = GlobalCtx->lookup(Name);
2755 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end();
2756 Alloc != AllocEnd; ++Alloc) {
2757 // Only look at non-template functions, as it is the predefined,
2758 // non-templated allocation function we are trying to declare here.
2759 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
2760 if (Func->getNumParams() == Params.size()) {
2761 llvm::SmallVector<QualType, 3> FuncParams;
2762 for (auto *P : Func->parameters())
2763 FuncParams.push_back(
2764 Context.getCanonicalType(P->getType().getUnqualifiedType()));
2765 if (llvm::makeArrayRef(FuncParams) == Params) {
2766 // Make the function visible to name lookup, even if we found it in
2767 // an unimported module. It either is an implicitly-declared global
2768 // allocation function, or is suppressing that function.
2769 Func->setVisibleDespiteOwningModule();
2776 FunctionProtoType::ExtProtoInfo EPI;
2778 QualType BadAllocType;
2779 bool HasBadAllocExceptionSpec
2780 = (Name.getCXXOverloadedOperator() == OO_New ||
2781 Name.getCXXOverloadedOperator() == OO_Array_New);
2782 if (HasBadAllocExceptionSpec) {
2783 if (!getLangOpts().CPlusPlus11) {
2784 BadAllocType = Context.getTypeDeclType(getStdBadAlloc());
2785 assert(StdBadAlloc && "Must have std::bad_alloc declared");
2786 EPI.ExceptionSpec.Type = EST_Dynamic;
2787 EPI.ExceptionSpec.Exceptions = llvm::makeArrayRef(BadAllocType);
2791 getLangOpts().CPlusPlus11 ? EST_BasicNoexcept : EST_DynamicNone;
2794 auto CreateAllocationFunctionDecl = [&](Attr *ExtraAttr) {
2795 QualType FnType = Context.getFunctionType(Return, Params, EPI);
2796 FunctionDecl *Alloc = FunctionDecl::Create(
2797 Context, GlobalCtx, SourceLocation(), SourceLocation(), Name,
2798 FnType, /*TInfo=*/nullptr, SC_None, false, true);
2799 Alloc->setImplicit();
2800 // Global allocation functions should always be visible.
2801 Alloc->setVisibleDespiteOwningModule();
2803 // Implicit sized deallocation functions always have default visibility.
2805 VisibilityAttr::CreateImplicit(Context, VisibilityAttr::Default));
2807 llvm::SmallVector<ParmVarDecl *, 3> ParamDecls;
2808 for (QualType T : Params) {
2809 ParamDecls.push_back(ParmVarDecl::Create(
2810 Context, Alloc, SourceLocation(), SourceLocation(), nullptr, T,
2811 /*TInfo=*/nullptr, SC_None, nullptr));
2812 ParamDecls.back()->setImplicit();
2814 Alloc->setParams(ParamDecls);
2816 Alloc->addAttr(ExtraAttr);
2817 Context.getTranslationUnitDecl()->addDecl(Alloc);
2818 IdResolver.tryAddTopLevelDecl(Alloc, Name);
2822 CreateAllocationFunctionDecl(nullptr);
2824 // Host and device get their own declaration so each can be
2825 // defined or re-declared independently.
2826 CreateAllocationFunctionDecl(CUDAHostAttr::CreateImplicit(Context));
2827 CreateAllocationFunctionDecl(CUDADeviceAttr::CreateImplicit(Context));
2831 FunctionDecl *Sema::FindUsualDeallocationFunction(SourceLocation StartLoc,
2832 bool CanProvideSize,
2834 DeclarationName Name) {
2835 DeclareGlobalNewDelete();
2837 LookupResult FoundDelete(*this, Name, StartLoc, LookupOrdinaryName);
2838 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2840 // FIXME: It's possible for this to result in ambiguity, through a
2841 // user-declared variadic operator delete or the enable_if attribute. We
2842 // should probably not consider those cases to be usual deallocation
2843 // functions. But for now we just make an arbitrary choice in that case.
2844 auto Result = resolveDeallocationOverload(*this, FoundDelete, CanProvideSize,
2846 assert(Result.FD && "operator delete missing from global scope?");
2850 FunctionDecl *Sema::FindDeallocationFunctionForDestructor(SourceLocation Loc,
2851 CXXRecordDecl *RD) {
2852 DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Delete);
2854 FunctionDecl *OperatorDelete = nullptr;
2855 if (FindDeallocationFunction(Loc, RD, Name, OperatorDelete))
2858 return OperatorDelete;
2860 // If there's no class-specific operator delete, look up the global
2861 // non-array delete.
2862 return FindUsualDeallocationFunction(
2863 Loc, true, hasNewExtendedAlignment(*this, Context.getRecordType(RD)),
2867 bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
2868 DeclarationName Name,
2869 FunctionDecl *&Operator, bool Diagnose) {
2870 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
2871 // Try to find operator delete/operator delete[] in class scope.
2872 LookupQualifiedName(Found, RD);
2874 if (Found.isAmbiguous())
2877 Found.suppressDiagnostics();
2879 bool Overaligned = hasNewExtendedAlignment(*this, Context.getRecordType(RD));
2881 // C++17 [expr.delete]p10:
2882 // If the deallocation functions have class scope, the one without a
2883 // parameter of type std::size_t is selected.
2884 llvm::SmallVector<UsualDeallocFnInfo, 4> Matches;
2885 resolveDeallocationOverload(*this, Found, /*WantSize*/ false,
2886 /*WantAlign*/ Overaligned, &Matches);
2888 // If we could find an overload, use it.
2889 if (Matches.size() == 1) {
2890 Operator = cast<CXXMethodDecl>(Matches[0].FD);
2892 // FIXME: DiagnoseUseOfDecl?
2893 if (Operator->isDeleted()) {
2895 Diag(StartLoc, diag::err_deleted_function_use);
2896 NoteDeletedFunction(Operator);
2901 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(),
2902 Matches[0].Found, Diagnose) == AR_inaccessible)
2908 // We found multiple suitable operators; complain about the ambiguity.
2909 // FIXME: The standard doesn't say to do this; it appears that the intent
2910 // is that this should never happen.
2911 if (!Matches.empty()) {
2913 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found)
2915 for (auto &Match : Matches)
2916 Diag(Match.FD->getLocation(), diag::note_member_declared_here) << Name;
2921 // We did find operator delete/operator delete[] declarations, but
2922 // none of them were suitable.
2923 if (!Found.empty()) {
2925 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found)
2928 for (NamedDecl *D : Found)
2929 Diag(D->getUnderlyingDecl()->getLocation(),
2930 diag::note_member_declared_here) << Name;
2940 /// Checks whether delete-expression, and new-expression used for
2941 /// initializing deletee have the same array form.
2942 class MismatchingNewDeleteDetector {
2944 enum MismatchResult {
2945 /// Indicates that there is no mismatch or a mismatch cannot be proven.
2947 /// Indicates that variable is initialized with mismatching form of \a new.
2949 /// Indicates that member is initialized with mismatching form of \a new.
2950 MemberInitMismatches,
2951 /// Indicates that 1 or more constructors' definitions could not been
2952 /// analyzed, and they will be checked again at the end of translation unit.
2956 /// \param EndOfTU True, if this is the final analysis at the end of
2957 /// translation unit. False, if this is the initial analysis at the point
2958 /// delete-expression was encountered.
2959 explicit MismatchingNewDeleteDetector(bool EndOfTU)
2960 : Field(nullptr), IsArrayForm(false), EndOfTU(EndOfTU),
2961 HasUndefinedConstructors(false) {}
2963 /// Checks whether pointee of a delete-expression is initialized with
2964 /// matching form of new-expression.
2966 /// If return value is \c VarInitMismatches or \c MemberInitMismatches at the
2967 /// point where delete-expression is encountered, then a warning will be
2968 /// issued immediately. If return value is \c AnalyzeLater at the point where
2969 /// delete-expression is seen, then member will be analyzed at the end of
2970 /// translation unit. \c AnalyzeLater is returned iff at least one constructor
2971 /// couldn't be analyzed. If at least one constructor initializes the member
2972 /// with matching type of new, the return value is \c NoMismatch.
2973 MismatchResult analyzeDeleteExpr(const CXXDeleteExpr *DE);
2974 /// Analyzes a class member.
2975 /// \param Field Class member to analyze.
2976 /// \param DeleteWasArrayForm Array form-ness of the delete-expression used
2977 /// for deleting the \p Field.
2978 MismatchResult analyzeField(FieldDecl *Field, bool DeleteWasArrayForm);
2980 /// List of mismatching new-expressions used for initialization of the pointee
2981 llvm::SmallVector<const CXXNewExpr *, 4> NewExprs;
2982 /// Indicates whether delete-expression was in array form.
2987 /// Indicates that there is at least one constructor without body.
2988 bool HasUndefinedConstructors;
2989 /// Returns \c CXXNewExpr from given initialization expression.
2990 /// \param E Expression used for initializing pointee in delete-expression.
2991 /// E can be a single-element \c InitListExpr consisting of new-expression.
2992 const CXXNewExpr *getNewExprFromInitListOrExpr(const Expr *E);
2993 /// Returns whether member is initialized with mismatching form of
2994 /// \c new either by the member initializer or in-class initialization.
2996 /// If bodies of all constructors are not visible at the end of translation
2997 /// unit or at least one constructor initializes member with the matching
2998 /// form of \c new, mismatch cannot be proven, and this function will return
3000 MismatchResult analyzeMemberExpr(const MemberExpr *ME);
3001 /// Returns whether variable is initialized with mismatching form of
3004 /// If variable is initialized with matching form of \c new or variable is not
3005 /// initialized with a \c new expression, this function will return true.
3006 /// If variable is initialized with mismatching form of \c new, returns false.
3007 /// \param D Variable to analyze.
3008 bool hasMatchingVarInit(const DeclRefExpr *D);
3009 /// Checks whether the constructor initializes pointee with mismatching
3012 /// Returns true, if member is initialized with matching form of \c new in
3013 /// member initializer list. Returns false, if member is initialized with the
3014 /// matching form of \c new in this constructor's initializer or given
3015 /// constructor isn't defined at the point where delete-expression is seen, or
3016 /// member isn't initialized by the constructor.
3017 bool hasMatchingNewInCtor(const CXXConstructorDecl *CD);
3018 /// Checks whether member is initialized with matching form of
3019 /// \c new in member initializer list.
3020 bool hasMatchingNewInCtorInit(const CXXCtorInitializer *CI);
3021 /// Checks whether member is initialized with mismatching form of \c new by
3022 /// in-class initializer.
3023 MismatchResult analyzeInClassInitializer();
3027 MismatchingNewDeleteDetector::MismatchResult
3028 MismatchingNewDeleteDetector::analyzeDeleteExpr(const CXXDeleteExpr *DE) {
3030 assert(DE && "Expected delete-expression");
3031 IsArrayForm = DE->isArrayForm();
3032 const Expr *E = DE->getArgument()->IgnoreParenImpCasts();
3033 if (const MemberExpr *ME = dyn_cast<const MemberExpr>(E)) {
3034 return analyzeMemberExpr(ME);
3035 } else if (const DeclRefExpr *D = dyn_cast<const DeclRefExpr>(E)) {
3036 if (!hasMatchingVarInit(D))
3037 return VarInitMismatches;
3043 MismatchingNewDeleteDetector::getNewExprFromInitListOrExpr(const Expr *E) {
3044 assert(E != nullptr && "Expected a valid initializer expression");
3045 E = E->IgnoreParenImpCasts();
3046 if (const InitListExpr *ILE = dyn_cast<const InitListExpr>(E)) {
3047 if (ILE->getNumInits() == 1)
3048 E = dyn_cast<const CXXNewExpr>(ILE->getInit(0)->IgnoreParenImpCasts());
3051 return dyn_cast_or_null<const CXXNewExpr>(E);
3054 bool MismatchingNewDeleteDetector::hasMatchingNewInCtorInit(
3055 const CXXCtorInitializer *CI) {
3056 const CXXNewExpr *NE = nullptr;
3057 if (Field == CI->getMember() &&
3058 (NE = getNewExprFromInitListOrExpr(CI->getInit()))) {
3059 if (NE->isArray() == IsArrayForm)
3062 NewExprs.push_back(NE);
3067 bool MismatchingNewDeleteDetector::hasMatchingNewInCtor(
3068 const CXXConstructorDecl *CD) {
3069 if (CD->isImplicit())
3071 const FunctionDecl *Definition = CD;
3072 if (!CD->isThisDeclarationADefinition() && !CD->isDefined(Definition)) {
3073 HasUndefinedConstructors = true;
3076 for (const auto *CI : cast<const CXXConstructorDecl>(Definition)->inits()) {
3077 if (hasMatchingNewInCtorInit(CI))
3083 MismatchingNewDeleteDetector::MismatchResult
3084 MismatchingNewDeleteDetector::analyzeInClassInitializer() {
3085 assert(Field != nullptr && "This should be called only for members");
3086 const Expr *InitExpr = Field->getInClassInitializer();
3088 return EndOfTU ? NoMismatch : AnalyzeLater;
3089 if (const CXXNewExpr *NE = getNewExprFromInitListOrExpr(InitExpr)) {
3090 if (NE->isArray() != IsArrayForm) {
3091 NewExprs.push_back(NE);
3092 return MemberInitMismatches;
3098 MismatchingNewDeleteDetector::MismatchResult
3099 MismatchingNewDeleteDetector::analyzeField(FieldDecl *Field,
3100 bool DeleteWasArrayForm) {
3101 assert(Field != nullptr && "Analysis requires a valid class member.");
3102 this->Field = Field;
3103 IsArrayForm = DeleteWasArrayForm;
3104 const CXXRecordDecl *RD = cast<const CXXRecordDecl>(Field->getParent());
3105 for (const auto *CD : RD->ctors()) {
3106 if (hasMatchingNewInCtor(CD))
3109 if (HasUndefinedConstructors)
3110 return EndOfTU ? NoMismatch : AnalyzeLater;
3111 if (!NewExprs.empty())
3112 return MemberInitMismatches;
3113 return Field->hasInClassInitializer() ? analyzeInClassInitializer()
3117 MismatchingNewDeleteDetector::MismatchResult
3118 MismatchingNewDeleteDetector::analyzeMemberExpr(const MemberExpr *ME) {
3119 assert(ME != nullptr && "Expected a member expression");
3120 if (FieldDecl *F = dyn_cast<FieldDecl>(ME->getMemberDecl()))
3121 return analyzeField(F, IsArrayForm);
3125 bool MismatchingNewDeleteDetector::hasMatchingVarInit(const DeclRefExpr *D) {
3126 const CXXNewExpr *NE = nullptr;
3127 if (const VarDecl *VD = dyn_cast<const VarDecl>(D->getDecl())) {
3128 if (VD->hasInit() && (NE = getNewExprFromInitListOrExpr(VD->getInit())) &&
3129 NE->isArray() != IsArrayForm) {
3130 NewExprs.push_back(NE);
3133 return NewExprs.empty();
3137 DiagnoseMismatchedNewDelete(Sema &SemaRef, SourceLocation DeleteLoc,
3138 const MismatchingNewDeleteDetector &Detector) {
3139 SourceLocation EndOfDelete = SemaRef.getLocForEndOfToken(DeleteLoc);
3141 if (!Detector.IsArrayForm)
3142 H = FixItHint::CreateInsertion(EndOfDelete, "[]");
3144 SourceLocation RSquare = Lexer::findLocationAfterToken(
3145 DeleteLoc, tok::l_square, SemaRef.getSourceManager(),
3146 SemaRef.getLangOpts(), true);
3147 if (RSquare.isValid())
3148 H = FixItHint::CreateRemoval(SourceRange(EndOfDelete, RSquare));
3150 SemaRef.Diag(DeleteLoc, diag::warn_mismatched_delete_new)
3151 << Detector.IsArrayForm << H;
3153 for (const auto *NE : Detector.NewExprs)
3154 SemaRef.Diag(NE->getExprLoc(), diag::note_allocated_here)
3155 << Detector.IsArrayForm;
3158 void Sema::AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE) {
3159 if (Diags.isIgnored(diag::warn_mismatched_delete_new, SourceLocation()))
3161 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/false);
3162 switch (Detector.analyzeDeleteExpr(DE)) {
3163 case MismatchingNewDeleteDetector::VarInitMismatches:
3164 case MismatchingNewDeleteDetector::MemberInitMismatches: {
3165 DiagnoseMismatchedNewDelete(*this, DE->getLocStart(), Detector);
3168 case MismatchingNewDeleteDetector::AnalyzeLater: {
3169 DeleteExprs[Detector.Field].push_back(
3170 std::make_pair(DE->getLocStart(), DE->isArrayForm()));
3173 case MismatchingNewDeleteDetector::NoMismatch:
3178 void Sema::AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
3179 bool DeleteWasArrayForm) {
3180 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/true);
3181 switch (Detector.analyzeField(Field, DeleteWasArrayForm)) {
3182 case MismatchingNewDeleteDetector::VarInitMismatches:
3183 llvm_unreachable("This analysis should have been done for class members.");
3184 case MismatchingNewDeleteDetector::AnalyzeLater:
3185 llvm_unreachable("Analysis cannot be postponed any point beyond end of "
3186 "translation unit.");
3187 case MismatchingNewDeleteDetector::MemberInitMismatches:
3188 DiagnoseMismatchedNewDelete(*this, DeleteLoc, Detector);
3190 case MismatchingNewDeleteDetector::NoMismatch:
3195 /// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in:
3196 /// @code ::delete ptr; @endcode
3198 /// @code delete [] ptr; @endcode
3200 Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
3201 bool ArrayForm, Expr *ExE) {
3202 // C++ [expr.delete]p1:
3203 // The operand shall have a pointer type, or a class type having a single
3204 // non-explicit conversion function to a pointer type. The result has type
3207 // DR599 amends "pointer type" to "pointer to object type" in both cases.
3209 ExprResult Ex = ExE;
3210 FunctionDecl *OperatorDelete = nullptr;
3211 bool ArrayFormAsWritten = ArrayForm;
3212 bool UsualArrayDeleteWantsSize = false;
3214 if (!Ex.get()->isTypeDependent()) {
3215 // Perform lvalue-to-rvalue cast, if needed.
3216 Ex = DefaultLvalueConversion(Ex.get());
3220 QualType Type = Ex.get()->getType();
3222 class DeleteConverter : public ContextualImplicitConverter {
3224 DeleteConverter() : ContextualImplicitConverter(false, true) {}
3226 bool match(QualType ConvType) override {
3227 // FIXME: If we have an operator T* and an operator void*, we must pick
3229 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
3230 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType())
3235 SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
3236 QualType T) override {
3237 return S.Diag(Loc, diag::err_delete_operand) << T;
3240 SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
3241 QualType T) override {
3242 return S.Diag(Loc, diag::err_delete_incomplete_class_type) << T;
3245 SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
3247 QualType ConvTy) override {
3248 return S.Diag(Loc, diag::err_delete_explicit_conversion) << T << ConvTy;
3251 SemaDiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
3252 QualType ConvTy) override {
3253 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3257 SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
3258 QualType T) override {
3259 return S.Diag(Loc, diag::err_ambiguous_delete_operand) << T;
3262 SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
3263 QualType ConvTy) override {
3264 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3268 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
3270 QualType ConvTy) override {
3271 llvm_unreachable("conversion functions are permitted");
3275 Ex = PerformContextualImplicitConversion(StartLoc, Ex.get(), Converter);
3278 Type = Ex.get()->getType();
3279 if (!Converter.match(Type))
3280 // FIXME: PerformContextualImplicitConversion should return ExprError
3281 // itself in this case.
3284 QualType Pointee = Type->getAs<PointerType>()->getPointeeType();
3285 QualType PointeeElem = Context.getBaseElementType(Pointee);
3287 if (Pointee.getAddressSpace() != LangAS::Default &&
3288 !getLangOpts().OpenCLCPlusPlus)
3289 return Diag(Ex.get()->getLocStart(),
3290 diag::err_address_space_qualified_delete)
3291 << Pointee.getUnqualifiedType()
3292 << Pointee.getQualifiers().getAddressSpaceAttributePrintValue();
3294 CXXRecordDecl *PointeeRD = nullptr;
3295 if (Pointee->isVoidType() && !isSFINAEContext()) {
3296 // The C++ standard bans deleting a pointer to a non-object type, which
3297 // effectively bans deletion of "void*". However, most compilers support
3298 // this, so we treat it as a warning unless we're in a SFINAE context.
3299 Diag(StartLoc, diag::ext_delete_void_ptr_operand)
3300 << Type << Ex.get()->getSourceRange();
3301 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) {
3302 return ExprError(Diag(StartLoc, diag::err_delete_operand)
3303 << Type << Ex.get()->getSourceRange());
3304 } else if (!Pointee->isDependentType()) {
3305 // FIXME: This can result in errors if the definition was imported from a
3306 // module but is hidden.
3307 if (!RequireCompleteType(StartLoc, Pointee,
3308 diag::warn_delete_incomplete, Ex.get())) {
3309 if (const RecordType *RT = PointeeElem->getAs<RecordType>())
3310 PointeeRD = cast<CXXRecordDecl>(RT->getDecl());
3314 if (Pointee->isArrayType() && !ArrayForm) {
3315 Diag(StartLoc, diag::warn_delete_array_type)
3316 << Type << Ex.get()->getSourceRange()
3317 << FixItHint::CreateInsertion(getLocForEndOfToken(StartLoc), "[]");
3321 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
3322 ArrayForm ? OO_Array_Delete : OO_Delete);
3326 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName,
3330 // If we're allocating an array of records, check whether the
3331 // usual operator delete[] has a size_t parameter.
3333 // If the user specifically asked to use the global allocator,
3334 // we'll need to do the lookup into the class.
3336 UsualArrayDeleteWantsSize =
3337 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem);
3339 // Otherwise, the usual operator delete[] should be the
3340 // function we just found.
3341 else if (OperatorDelete && isa<CXXMethodDecl>(OperatorDelete))
3342 UsualArrayDeleteWantsSize =
3343 UsualDeallocFnInfo(*this,
3344 DeclAccessPair::make(OperatorDelete, AS_public))
3348 if (!PointeeRD->hasIrrelevantDestructor())
3349 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3350 MarkFunctionReferenced(StartLoc,
3351 const_cast<CXXDestructorDecl*>(Dtor));
3352 if (DiagnoseUseOfDecl(Dtor, StartLoc))
3356 CheckVirtualDtorCall(PointeeRD->getDestructor(), StartLoc,
3357 /*IsDelete=*/true, /*CallCanBeVirtual=*/true,
3358 /*WarnOnNonAbstractTypes=*/!ArrayForm,
3362 if (!OperatorDelete) {
3363 if (getLangOpts().OpenCLCPlusPlus) {
3364 Diag(StartLoc, diag::err_openclcxx_not_supported) << "default delete";
3368 bool IsComplete = isCompleteType(StartLoc, Pointee);
3369 bool CanProvideSize =
3370 IsComplete && (!ArrayForm || UsualArrayDeleteWantsSize ||
3371 Pointee.isDestructedType());
3372 bool Overaligned = hasNewExtendedAlignment(*this, Pointee);
3374 // Look for a global declaration.
3375 OperatorDelete = FindUsualDeallocationFunction(StartLoc, CanProvideSize,
3376 Overaligned, DeleteName);
3379 MarkFunctionReferenced(StartLoc, OperatorDelete);
3381 // Check access and ambiguity of destructor if we're going to call it.
3382 // Note that this is required even for a virtual delete.
3383 bool IsVirtualDelete = false;
3385 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3386 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor,
3387 PDiag(diag::err_access_dtor) << PointeeElem);
3388 IsVirtualDelete = Dtor->isVirtual();
3392 diagnoseUnavailableAlignedAllocation(*OperatorDelete, StartLoc, true,
3395 // Convert the operand to the type of the first parameter of operator
3396 // delete. This is only necessary if we selected a destroying operator
3397 // delete that we are going to call (non-virtually); converting to void*
3398 // is trivial and left to AST consumers to handle.
3399 QualType ParamType = OperatorDelete->getParamDecl(0)->getType();
3400 if (!IsVirtualDelete && !ParamType->getPointeeType()->isVoidType()) {
3401 Qualifiers Qs = Pointee.getQualifiers();
3402 if (Qs.hasCVRQualifiers()) {
3403 // Qualifiers are irrelevant to this conversion; we're only looking
3404 // for access and ambiguity.
3405 Qs.removeCVRQualifiers();
3406 QualType Unqual = Context.getPointerType(
3407 Context.getQualifiedType(Pointee.getUnqualifiedType(), Qs));
3408 Ex = ImpCastExprToType(Ex.get(), Unqual, CK_NoOp);
3410 Ex = PerformImplicitConversion(Ex.get(), ParamType, AA_Passing);
3416 CXXDeleteExpr *Result = new (Context) CXXDeleteExpr(
3417 Context.VoidTy, UseGlobal, ArrayForm, ArrayFormAsWritten,
3418 UsualArrayDeleteWantsSize, OperatorDelete, Ex.get(), StartLoc);
3419 AnalyzeDeleteExprMismatch(Result);
3423 static bool resolveBuiltinNewDeleteOverload(Sema &S, CallExpr *TheCall,
3425 FunctionDecl *&Operator) {
3427 DeclarationName NewName = S.Context.DeclarationNames.getCXXOperatorName(
3428 IsDelete ? OO_Delete : OO_New);
3430 LookupResult R(S, NewName, TheCall->getLocStart(), Sema::LookupOrdinaryName);
3431 S.LookupQualifiedName(R, S.Context.getTranslationUnitDecl());
3432 assert(!R.empty() && "implicitly declared allocation functions not found");
3433 assert(!R.isAmbiguous() && "global allocation functions are ambiguous");
3435 // We do our own custom access checks below.
3436 R.suppressDiagnostics();
3438 SmallVector<Expr *, 8> Args(TheCall->arg_begin(), TheCall->arg_end());
3439 OverloadCandidateSet Candidates(R.getNameLoc(),
3440 OverloadCandidateSet::CSK_Normal);
3441 for (LookupResult::iterator FnOvl = R.begin(), FnOvlEnd = R.end();
3442 FnOvl != FnOvlEnd; ++FnOvl) {
3443 // Even member operator new/delete are implicitly treated as
3444 // static, so don't use AddMemberCandidate.
3445 NamedDecl *D = (*FnOvl)->getUnderlyingDecl();
3447 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
3448 S.AddTemplateOverloadCandidate(FnTemplate, FnOvl.getPair(),
3449 /*ExplicitTemplateArgs=*/nullptr, Args,
3451 /*SuppressUserConversions=*/false);
3455 FunctionDecl *Fn = cast<FunctionDecl>(D);
3456 S.AddOverloadCandidate(Fn, FnOvl.getPair(), Args, Candidates,
3457 /*SuppressUserConversions=*/false);
3460 SourceRange Range = TheCall->getSourceRange();
3462 // Do the resolution.
3463 OverloadCandidateSet::iterator Best;
3464 switch (Candidates.BestViableFunction(S, R.getNameLoc(), Best)) {
3467 FunctionDecl *FnDecl = Best->Function;
3468 assert(R.getNamingClass() == nullptr &&
3469 "class members should not be considered");
3471 if (!FnDecl->isReplaceableGlobalAllocationFunction()) {
3472 S.Diag(R.getNameLoc(), diag::err_builtin_operator_new_delete_not_usual)
3473 << (IsDelete ? 1 : 0) << Range;
3474 S.Diag(FnDecl->getLocation(), diag::note_non_usual_function_declared_here)
3475 << R.getLookupName() << FnDecl->getSourceRange();
3483 case OR_No_Viable_Function:
3484 S.Diag(R.getNameLoc(), diag::err_ovl_no_viable_function_in_call)
3485 << R.getLookupName() << Range;
3486 Candidates.NoteCandidates(S, OCD_AllCandidates, Args);
3490 S.Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call)
3491 << R.getLookupName() << Range;
3492 Candidates.NoteCandidates(S, OCD_ViableCandidates, Args);
3496 S.Diag(R.getNameLoc(), diag::err_ovl_deleted_call)
3497 << Best->Function->isDeleted() << R.getLookupName()
3498 << S.getDeletedOrUnavailableSuffix(Best->Function) << Range;
3499 Candidates.NoteCandidates(S, OCD_AllCandidates, Args);
3503 llvm_unreachable("Unreachable, bad result from BestViableFunction");
3507 Sema::SemaBuiltinOperatorNewDeleteOverloaded(ExprResult TheCallResult,
3509 CallExpr *TheCall = cast<CallExpr>(TheCallResult.get());
3510 if (!getLangOpts().CPlusPlus) {
3511 Diag(TheCall->getExprLoc(), diag::err_builtin_requires_language)
3512 << (IsDelete ? "__builtin_operator_delete" : "__builtin_operator_new")
3516 // CodeGen assumes it can find the global new and delete to call,
3517 // so ensure that they are declared.
3518 DeclareGlobalNewDelete();
3520 FunctionDecl *OperatorNewOrDelete = nullptr;
3521 if (resolveBuiltinNewDeleteOverload(*this, TheCall, IsDelete,
3522 OperatorNewOrDelete))
3524 assert(OperatorNewOrDelete && "should be found");
3526 TheCall->setType(OperatorNewOrDelete->getReturnType());
3527 for (unsigned i = 0; i != TheCall->getNumArgs(); ++i) {
3528 QualType ParamTy = OperatorNewOrDelete->getParamDecl(i)->getType();
3529 InitializedEntity Entity =
3530 InitializedEntity::InitializeParameter(Context, ParamTy, false);
3531 ExprResult Arg = PerformCopyInitialization(
3532 Entity, TheCall->getArg(i)->getLocStart(), TheCall->getArg(i));
3533 if (Arg.isInvalid())
3535 TheCall->setArg(i, Arg.get());
3537 auto Callee = dyn_cast<ImplicitCastExpr>(TheCall->getCallee());
3538 assert(Callee && Callee->getCastKind() == CK_BuiltinFnToFnPtr &&
3539 "Callee expected to be implicit cast to a builtin function pointer");
3540 Callee->setType(OperatorNewOrDelete->getType());
3542 return TheCallResult;
3545 void Sema::CheckVirtualDtorCall(CXXDestructorDecl *dtor, SourceLocation Loc,
3546 bool IsDelete, bool CallCanBeVirtual,
3547 bool WarnOnNonAbstractTypes,
3548 SourceLocation DtorLoc) {
3549 if (!dtor || dtor->isVirtual() || !CallCanBeVirtual || isUnevaluatedContext())
3552 // C++ [expr.delete]p3:
3553 // In the first alternative (delete object), if the static type of the
3554 // object to be deleted is different from its dynamic type, the static
3555 // type shall be a base class of the dynamic type of the object to be
3556 // deleted and the static type shall have a virtual destructor or the
3557 // behavior is undefined.
3559 const CXXRecordDecl *PointeeRD = dtor->getParent();
3560 // Note: a final class cannot be derived from, no issue there
3561 if (!PointeeRD->isPolymorphic() || PointeeRD->hasAttr<FinalAttr>())
3564 // If the superclass is in a system header, there's nothing that can be done.
3565 // The `delete` (where we emit the warning) can be in a system header,
3566 // what matters for this warning is where the deleted type is defined.
3567 if (getSourceManager().isInSystemHeader(PointeeRD->getLocation()))
3570 QualType ClassType = dtor->getThisType(Context)->getPointeeType();
3571 if (PointeeRD->isAbstract()) {
3572 // If the class is abstract, we warn by default, because we're
3573 // sure the code has undefined behavior.
3574 Diag(Loc, diag::warn_delete_abstract_non_virtual_dtor) << (IsDelete ? 0 : 1)
3576 } else if (WarnOnNonAbstractTypes) {
3577 // Otherwise, if this is not an array delete, it's a bit suspect,
3578 // but not necessarily wrong.
3579 Diag(Loc, diag::warn_delete_non_virtual_dtor) << (IsDelete ? 0 : 1)
3583 std::string TypeStr;
3584 ClassType.getAsStringInternal(TypeStr, getPrintingPolicy());
3585 Diag(DtorLoc, diag::note_delete_non_virtual)
3586 << FixItHint::CreateInsertion(DtorLoc, TypeStr + "::");
3590 Sema::ConditionResult Sema::ActOnConditionVariable(Decl *ConditionVar,
3591 SourceLocation StmtLoc,
3594 CheckConditionVariable(cast<VarDecl>(ConditionVar), StmtLoc, CK);
3596 return ConditionError();
3597 return ConditionResult(*this, ConditionVar, MakeFullExpr(E.get(), StmtLoc),
3598 CK == ConditionKind::ConstexprIf);
3601 /// Check the use of the given variable as a C++ condition in an if,
3602 /// while, do-while, or switch statement.
3603 ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar,
3604 SourceLocation StmtLoc,
3606 if (ConditionVar->isInvalidDecl())
3609 QualType T = ConditionVar->getType();
3611 // C++ [stmt.select]p2:
3612 // The declarator shall not specify a function or an array.
3613 if (T->isFunctionType())
3614 return ExprError(Diag(ConditionVar->getLocation(),
3615 diag::err_invalid_use_of_function_type)
3616 << ConditionVar->getSourceRange());
3617 else if (T->isArrayType())
3618 return ExprError(Diag(ConditionVar->getLocation(),
3619 diag::err_invalid_use_of_array_type)
3620 << ConditionVar->getSourceRange());
3622 ExprResult Condition = DeclRefExpr::Create(
3623 Context, NestedNameSpecifierLoc(), SourceLocation(), ConditionVar,
3624 /*enclosing*/ false, ConditionVar->getLocation(),
3625 ConditionVar->getType().getNonReferenceType(), VK_LValue);
3627 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get()));
3630 case ConditionKind::Boolean:
3631 return CheckBooleanCondition(StmtLoc, Condition.get());
3633 case ConditionKind::ConstexprIf:
3634 return CheckBooleanCondition(StmtLoc, Condition.get(), true);
3636 case ConditionKind::Switch:
3637 return CheckSwitchCondition(StmtLoc, Condition.get());
3640 llvm_unreachable("unexpected condition kind");
3643 /// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
3644 ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr, bool IsConstexpr) {
3646 // The value of a condition that is an initialized declaration in a statement
3647 // other than a switch statement is the value of the declared variable
3648 // implicitly converted to type bool. If that conversion is ill-formed, the
3649 // program is ill-formed.
3650 // The value of a condition that is an expression is the value of the
3651 // expression, implicitly converted to bool.
3653 // FIXME: Return this value to the caller so they don't need to recompute it.
3654 llvm::APSInt Value(/*BitWidth*/1);
3655 return (IsConstexpr && !CondExpr->isValueDependent())
3656 ? CheckConvertedConstantExpression(CondExpr, Context.BoolTy, Value,
3658 : PerformContextuallyConvertToBool(CondExpr);
3661 /// Helper function to determine whether this is the (deprecated) C++
3662 /// conversion from a string literal to a pointer to non-const char or
3663 /// non-const wchar_t (for narrow and wide string literals,
3666 Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) {
3667 // Look inside the implicit cast, if it exists.
3668 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From))
3669 From = Cast->getSubExpr();
3671 // A string literal (2.13.4) that is not a wide string literal can
3672 // be converted to an rvalue of type "pointer to char"; a wide
3673 // string literal can be converted to an rvalue of type "pointer
3674 // to wchar_t" (C++ 4.2p2).
3675 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens()))
3676 if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
3677 if (const BuiltinType *ToPointeeType
3678 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
3679 // This conversion is considered only when there is an
3680 // explicit appropriate pointer target type (C++ 4.2p2).
3681 if (!ToPtrType->getPointeeType().hasQualifiers()) {
3682 switch (StrLit->getKind()) {
3683 case StringLiteral::UTF8:
3684 case StringLiteral::UTF16:
3685 case StringLiteral::UTF32:
3686 // We don't allow UTF literals to be implicitly converted
3688 case StringLiteral::Ascii:
3689 return (ToPointeeType->getKind() == BuiltinType::Char_U ||
3690 ToPointeeType->getKind() == BuiltinType::Char_S);
3691 case StringLiteral::Wide:
3692 return Context.typesAreCompatible(Context.getWideCharType(),
3693 QualType(ToPointeeType, 0));
3701 static ExprResult BuildCXXCastArgument(Sema &S,
3702 SourceLocation CastLoc,
3705 CXXMethodDecl *Method,
3706 DeclAccessPair FoundDecl,
3707 bool HadMultipleCandidates,
3710 default: llvm_unreachable("Unhandled cast kind!");
3711 case CK_ConstructorConversion: {
3712 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method);
3713 SmallVector<Expr*, 8> ConstructorArgs;
3715 if (S.RequireNonAbstractType(CastLoc, Ty,
3716 diag::err_allocation_of_abstract_type))
3719 if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs))
3722 S.CheckConstructorAccess(CastLoc, Constructor, FoundDecl,
3723 InitializedEntity::InitializeTemporary(Ty));
3724 if (S.DiagnoseUseOfDecl(Method, CastLoc))
3727 ExprResult Result = S.BuildCXXConstructExpr(
3728 CastLoc, Ty, FoundDecl, cast<CXXConstructorDecl>(Method),
3729 ConstructorArgs, HadMultipleCandidates,
3730 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3731 CXXConstructExpr::CK_Complete, SourceRange());
3732 if (Result.isInvalid())
3735 return S.MaybeBindToTemporary(Result.getAs<Expr>());
3738 case CK_UserDefinedConversion: {
3739 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
3741 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ nullptr, FoundDecl);
3742 if (S.DiagnoseUseOfDecl(Method, CastLoc))
3745 // Create an implicit call expr that calls it.
3746 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method);
3747 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv,
3748 HadMultipleCandidates);
3749 if (Result.isInvalid())
3751 // Record usage of conversion in an implicit cast.
3752 Result = ImplicitCastExpr::Create(S.Context, Result.get()->getType(),
3753 CK_UserDefinedConversion, Result.get(),
3754 nullptr, Result.get()->getValueKind());
3756 return S.MaybeBindToTemporary(Result.get());
3761 /// PerformImplicitConversion - Perform an implicit conversion of the
3762 /// expression From to the type ToType using the pre-computed implicit
3763 /// conversion sequence ICS. Returns the converted
3764 /// expression. Action is the kind of conversion we're performing,
3765 /// used in the error message.
3767 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
3768 const ImplicitConversionSequence &ICS,
3769 AssignmentAction Action,
3770 CheckedConversionKind CCK) {
3771 // C++ [over.match.oper]p7: [...] operands of class type are converted [...]
3772 if (CCK == CCK_ForBuiltinOverloadedOp && !From->getType()->isRecordType())
3775 switch (ICS.getKind()) {
3776 case ImplicitConversionSequence::StandardConversion: {
3777 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard,
3779 if (Res.isInvalid())
3785 case ImplicitConversionSequence::UserDefinedConversion: {
3787 FunctionDecl *FD = ICS.UserDefined.ConversionFunction;
3789 QualType BeforeToType;
3790 assert(FD && "no conversion function for user-defined conversion seq");
3791 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) {
3792 CastKind = CK_UserDefinedConversion;
3794 // If the user-defined conversion is specified by a conversion function,
3795 // the initial standard conversion sequence converts the source type to
3796 // the implicit object parameter of the conversion function.
3797 BeforeToType = Context.getTagDeclType(Conv->getParent());
3799 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD);
3800 CastKind = CK_ConstructorConversion;
3801 // Do no conversion if dealing with ... for the first conversion.
3802 if (!ICS.UserDefined.EllipsisConversion) {
3803 // If the user-defined conversion is specified by a constructor, the
3804 // initial standard conversion sequence converts the source type to
3805 // the type required by the argument of the constructor
3806 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType();
3809 // Watch out for ellipsis conversion.
3810 if (!ICS.UserDefined.EllipsisConversion) {
3812 PerformImplicitConversion(From, BeforeToType,
3813 ICS.UserDefined.Before, AA_Converting,
3815 if (Res.isInvalid())
3821 = BuildCXXCastArgument(*this,
3822 From->getLocStart(),
3823 ToType.getNonReferenceType(),
3824 CastKind, cast<CXXMethodDecl>(FD),
3825 ICS.UserDefined.FoundConversionFunction,
3826 ICS.UserDefined.HadMultipleCandidates,
3829 if (CastArg.isInvalid())
3832 From = CastArg.get();
3834 // C++ [over.match.oper]p7:
3835 // [...] the second standard conversion sequence of a user-defined
3836 // conversion sequence is not applied.
3837 if (CCK == CCK_ForBuiltinOverloadedOp)
3840 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
3841 AA_Converting, CCK);
3844 case ImplicitConversionSequence::AmbiguousConversion:
3845 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(),
3846 PDiag(diag::err_typecheck_ambiguous_condition)
3847 << From->getSourceRange());
3850 case ImplicitConversionSequence::EllipsisConversion:
3851 llvm_unreachable("Cannot perform an ellipsis conversion");
3853 case ImplicitConversionSequence::BadConversion:
3855 DiagnoseAssignmentResult(Incompatible, From->getExprLoc(), ToType,
3856 From->getType(), From, Action);
3857 assert(Diagnosed && "failed to diagnose bad conversion"); (void)Diagnosed;
3861 // Everything went well.
3865 /// PerformImplicitConversion - Perform an implicit conversion of the
3866 /// expression From to the type ToType by following the standard
3867 /// conversion sequence SCS. Returns the converted
3868 /// expression. Flavor is the context in which we're performing this
3869 /// conversion, for use in error messages.
3871 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
3872 const StandardConversionSequence& SCS,
3873 AssignmentAction Action,
3874 CheckedConversionKind CCK) {
3875 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast);
3877 // Overall FIXME: we are recomputing too many types here and doing far too
3878 // much extra work. What this means is that we need to keep track of more
3879 // information that is computed when we try the implicit conversion initially,
3880 // so that we don't need to recompute anything here.
3881 QualType FromType = From->getType();
3883 if (SCS.CopyConstructor) {
3884 // FIXME: When can ToType be a reference type?
3885 assert(!ToType->isReferenceType());
3886 if (SCS.Second == ICK_Derived_To_Base) {
3887 SmallVector<Expr*, 8> ConstructorArgs;
3888 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor),
3889 From, /*FIXME:ConstructLoc*/SourceLocation(),
3892 return BuildCXXConstructExpr(
3893 /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
3894 SCS.FoundCopyConstructor, SCS.CopyConstructor,
3895 ConstructorArgs, /*HadMultipleCandidates*/ false,
3896 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3897 CXXConstructExpr::CK_Complete, SourceRange());
3899 return BuildCXXConstructExpr(
3900 /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
3901 SCS.FoundCopyConstructor, SCS.CopyConstructor,
3902 From, /*HadMultipleCandidates*/ false,
3903 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3904 CXXConstructExpr::CK_Complete, SourceRange());
3907 // Resolve overloaded function references.
3908 if (Context.hasSameType(FromType, Context.OverloadTy)) {
3909 DeclAccessPair Found;
3910 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType,
3915 if (DiagnoseUseOfDecl(Fn, From->getLocStart()))
3918 From = FixOverloadedFunctionReference(From, Found, Fn);
3919 FromType = From->getType();
3922 // If we're converting to an atomic type, first convert to the corresponding
3924 QualType ToAtomicType;
3925 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) {
3926 ToAtomicType = ToType;
3927 ToType = ToAtomic->getValueType();
3930 QualType InitialFromType = FromType;
3931 // Perform the first implicit conversion.
3932 switch (SCS.First) {
3934 if (const AtomicType *FromAtomic = FromType->getAs<AtomicType>()) {
3935 FromType = FromAtomic->getValueType().getUnqualifiedType();
3936 From = ImplicitCastExpr::Create(Context, FromType, CK_AtomicToNonAtomic,
3937 From, /*BasePath=*/nullptr, VK_RValue);
3941 case ICK_Lvalue_To_Rvalue: {
3942 assert(From->getObjectKind() != OK_ObjCProperty);
3943 ExprResult FromRes = DefaultLvalueConversion(From);
3944 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!");
3945 From = FromRes.get();
3946 FromType = From->getType();
3950 case ICK_Array_To_Pointer:
3951 FromType = Context.getArrayDecayedType(FromType);
3952 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay,
3953 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3956 case ICK_Function_To_Pointer:
3957 FromType = Context.getPointerType(FromType);
3958 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay,
3959 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3963 llvm_unreachable("Improper first standard conversion");
3966 // Perform the second implicit conversion
3967 switch (SCS.Second) {
3969 // C++ [except.spec]p5:
3970 // [For] assignment to and initialization of pointers to functions,
3971 // pointers to member functions, and references to functions: the
3972 // target entity shall allow at least the exceptions allowed by the
3973 // source value in the assignment or initialization.
3976 case AA_Initializing:
3977 // Note, function argument passing and returning are initialization.
3981 case AA_Passing_CFAudited:
3982 if (CheckExceptionSpecCompatibility(From, ToType))
3988 // Casts and implicit conversions are not initialization, so are not
3989 // checked for exception specification mismatches.
3992 // Nothing else to do.
3995 case ICK_Integral_Promotion:
3996 case ICK_Integral_Conversion:
3997 if (ToType->isBooleanType()) {
3998 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() &&
3999 SCS.Second == ICK_Integral_Promotion &&
4000 "only enums with fixed underlying type can promote to bool");
4001 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean,
4002 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4004 From = ImpCastExprToType(From, ToType, CK_IntegralCast,
4005 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4009 case ICK_Floating_Promotion:
4010 case ICK_Floating_Conversion:
4011 From = ImpCastExprToType(From, ToType, CK_FloatingCast,
4012 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4015 case ICK_Complex_Promotion:
4016 case ICK_Complex_Conversion: {
4017 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType();
4018 QualType ToEl = ToType->getAs<ComplexType>()->getElementType();
4020 if (FromEl->isRealFloatingType()) {
4021 if (ToEl->isRealFloatingType())
4022 CK = CK_FloatingComplexCast;
4024 CK = CK_FloatingComplexToIntegralComplex;
4025 } else if (ToEl->isRealFloatingType()) {
4026 CK = CK_IntegralComplexToFloatingComplex;
4028 CK = CK_IntegralComplexCast;
4030 From = ImpCastExprToType(From, ToType, CK,
4031 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4035 case ICK_Floating_Integral:
4036 if (ToType->isRealFloatingType())
4037 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating,
4038 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4040 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral,
4041 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4044 case ICK_Compatible_Conversion:
4045 From = ImpCastExprToType(From, ToType, CK_NoOp,
4046 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4049 case ICK_Writeback_Conversion:
4050 case ICK_Pointer_Conversion: {
4051 if (SCS.IncompatibleObjC && Action != AA_Casting) {
4052 // Diagnose incompatible Objective-C conversions
4053 if (Action == AA_Initializing || Action == AA_Assigning)
4054 Diag(From->getLocStart(),
4055 diag::ext_typecheck_convert_incompatible_pointer)
4056 << ToType << From->getType() << Action
4057 << From->getSourceRange() << 0;
4059 Diag(From->getLocStart(),
4060 diag::ext_typecheck_convert_incompatible_pointer)
4061 << From->getType() << ToType << Action
4062 << From->getSourceRange() << 0;
4064 if (From->getType()->isObjCObjectPointerType() &&
4065 ToType->isObjCObjectPointerType())
4066 EmitRelatedResultTypeNote(From);
4067 } else if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
4068 !CheckObjCARCUnavailableWeakConversion(ToType,
4070 if (Action == AA_Initializing)
4071 Diag(From->getLocStart(),
4072 diag::err_arc_weak_unavailable_assign);
4074 Diag(From->getLocStart(),
4075 diag::err_arc_convesion_of_weak_unavailable)
4076 << (Action == AA_Casting) << From->getType() << ToType
4077 << From->getSourceRange();
4081 CXXCastPath BasePath;
4082 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle))
4085 // Make sure we extend blocks if necessary.
4086 // FIXME: doing this here is really ugly.
4087 if (Kind == CK_BlockPointerToObjCPointerCast) {
4088 ExprResult E = From;
4089 (void) PrepareCastToObjCObjectPointer(E);
4092 if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
4093 CheckObjCConversion(SourceRange(), ToType, From, CCK);
4094 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
4099 case ICK_Pointer_Member: {
4101 CXXCastPath BasePath;
4102 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle))
4104 if (CheckExceptionSpecCompatibility(From, ToType))
4107 // We may not have been able to figure out what this member pointer resolved
4108 // to up until this exact point. Attempt to lock-in it's inheritance model.
4109 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
4110 (void)isCompleteType(From->getExprLoc(), From->getType());
4111 (void)isCompleteType(From->getExprLoc(), ToType);
4114 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
4119 case ICK_Boolean_Conversion:
4120 // Perform half-to-boolean conversion via float.
4121 if (From->getType()->isHalfType()) {
4122 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).get();
4123 FromType = Context.FloatTy;
4126 From = ImpCastExprToType(From, Context.BoolTy,
4127 ScalarTypeToBooleanCastKind(FromType),
4128 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4131 case ICK_Derived_To_Base: {
4132 CXXCastPath BasePath;
4133 if (CheckDerivedToBaseConversion(From->getType(),
4134 ToType.getNonReferenceType(),
4135 From->getLocStart(),
4136 From->getSourceRange(),
4141 From = ImpCastExprToType(From, ToType.getNonReferenceType(),
4142 CK_DerivedToBase, From->getValueKind(),
4143 &BasePath, CCK).get();
4147 case ICK_Vector_Conversion:
4148 From = ImpCastExprToType(From, ToType, CK_BitCast,
4149 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4152 case ICK_Vector_Splat: {
4153 // Vector splat from any arithmetic type to a vector.
4154 Expr *Elem = prepareVectorSplat(ToType, From).get();
4155 From = ImpCastExprToType(Elem, ToType, CK_VectorSplat, VK_RValue,
4156 /*BasePath=*/nullptr, CCK).get();
4160 case ICK_Complex_Real:
4161 // Case 1. x -> _Complex y
4162 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) {
4163 QualType ElType = ToComplex->getElementType();
4164 bool isFloatingComplex = ElType->isRealFloatingType();
4167 if (Context.hasSameUnqualifiedType(ElType, From->getType())) {
4169 } else if (From->getType()->isRealFloatingType()) {
4170 From = ImpCastExprToType(From, ElType,
4171 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).get();
4173 assert(From->getType()->isIntegerType());
4174 From = ImpCastExprToType(From, ElType,
4175 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).get();
4178 From = ImpCastExprToType(From, ToType,
4179 isFloatingComplex ? CK_FloatingRealToComplex
4180 : CK_IntegralRealToComplex).get();
4182 // Case 2. _Complex x -> y
4184 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>();
4185 assert(FromComplex);
4187 QualType ElType = FromComplex->getElementType();
4188 bool isFloatingComplex = ElType->isRealFloatingType();
4191 From = ImpCastExprToType(From, ElType,
4192 isFloatingComplex ? CK_FloatingComplexToReal
4193 : CK_IntegralComplexToReal,
4194 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4197 if (Context.hasSameUnqualifiedType(ElType, ToType)) {
4199 } else if (ToType->isRealFloatingType()) {
4200 From = ImpCastExprToType(From, ToType,
4201 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating,
4202 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4204 assert(ToType->isIntegerType());
4205 From = ImpCastExprToType(From, ToType,
4206 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast,
4207 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4212 case ICK_Block_Pointer_Conversion: {
4213 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast,
4214 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4218 case ICK_TransparentUnionConversion: {
4219 ExprResult FromRes = From;
4220 Sema::AssignConvertType ConvTy =
4221 CheckTransparentUnionArgumentConstraints(ToType, FromRes);
4222 if (FromRes.isInvalid())
4224 From = FromRes.get();
4225 assert ((ConvTy == Sema::Compatible) &&
4226 "Improper transparent union conversion");
4231 case ICK_Zero_Event_Conversion:
4232 From = ImpCastExprToType(From, ToType,
4234 From->getValueKind()).get();
4237 case ICK_Zero_Queue_Conversion:
4238 From = ImpCastExprToType(From, ToType,
4240 From->getValueKind()).get();
4243 case ICK_Lvalue_To_Rvalue:
4244 case ICK_Array_To_Pointer:
4245 case ICK_Function_To_Pointer:
4246 case ICK_Function_Conversion:
4247 case ICK_Qualification:
4248 case ICK_Num_Conversion_Kinds:
4249 case ICK_C_Only_Conversion:
4250 case ICK_Incompatible_Pointer_Conversion:
4251 llvm_unreachable("Improper second standard conversion");
4254 switch (SCS.Third) {
4259 case ICK_Function_Conversion:
4260 // If both sides are functions (or pointers/references to them), there could
4261 // be incompatible exception declarations.
4262 if (CheckExceptionSpecCompatibility(From, ToType))
4265 From = ImpCastExprToType(From, ToType, CK_NoOp,
4266 VK_RValue, /*BasePath=*/nullptr, CCK).get();
4269 case ICK_Qualification: {
4270 // The qualification keeps the category of the inner expression, unless the
4271 // target type isn't a reference.
4272 ExprValueKind VK = ToType->isReferenceType() ?
4273 From->getValueKind() : VK_RValue;
4274 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context),
4275 CK_NoOp, VK, /*BasePath=*/nullptr, CCK).get();
4277 if (SCS.DeprecatedStringLiteralToCharPtr &&
4278 !getLangOpts().WritableStrings) {
4279 Diag(From->getLocStart(), getLangOpts().CPlusPlus11
4280 ? diag::ext_deprecated_string_literal_conversion
4281 : diag::warn_deprecated_string_literal_conversion)
4282 << ToType.getNonReferenceType();
4289 llvm_unreachable("Improper third standard conversion");
4292 // If this conversion sequence involved a scalar -> atomic conversion, perform
4293 // that conversion now.
4294 if (!ToAtomicType.isNull()) {
4295 assert(Context.hasSameType(
4296 ToAtomicType->castAs<AtomicType>()->getValueType(), From->getType()));
4297 From = ImpCastExprToType(From, ToAtomicType, CK_NonAtomicToAtomic,
4298 VK_RValue, nullptr, CCK).get();
4301 // If this conversion sequence succeeded and involved implicitly converting a
4302 // _Nullable type to a _Nonnull one, complain.
4304 diagnoseNullableToNonnullConversion(ToType, InitialFromType,
4305 From->getLocStart());
4310 /// Check the completeness of a type in a unary type trait.
4312 /// If the particular type trait requires a complete type, tries to complete
4313 /// it. If completing the type fails, a diagnostic is emitted and false
4314 /// returned. If completing the type succeeds or no completion was required,
4316 static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, TypeTrait UTT,
4319 // C++0x [meta.unary.prop]p3:
4320 // For all of the class templates X declared in this Clause, instantiating
4321 // that template with a template argument that is a class template
4322 // specialization may result in the implicit instantiation of the template
4323 // argument if and only if the semantics of X require that the argument
4324 // must be a complete type.
4325 // We apply this rule to all the type trait expressions used to implement
4326 // these class templates. We also try to follow any GCC documented behavior
4327 // in these expressions to ensure portability of standard libraries.
4329 default: llvm_unreachable("not a UTT");
4330 // is_complete_type somewhat obviously cannot require a complete type.
4331 case UTT_IsCompleteType:
4334 // These traits are modeled on the type predicates in C++0x
4335 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as
4336 // requiring a complete type, as whether or not they return true cannot be
4337 // impacted by the completeness of the type.
4339 case UTT_IsIntegral:
4340 case UTT_IsFloatingPoint:
4343 case UTT_IsLvalueReference:
4344 case UTT_IsRvalueReference:
4345 case UTT_IsMemberFunctionPointer:
4346 case UTT_IsMemberObjectPointer:
4350 case UTT_IsFunction:
4351 case UTT_IsReference:
4352 case UTT_IsArithmetic:
4353 case UTT_IsFundamental:
4356 case UTT_IsCompound:
4357 case UTT_IsMemberPointer:
4360 // These traits are modeled on type predicates in C++0x [meta.unary.prop]
4361 // which requires some of its traits to have the complete type. However,
4362 // the completeness of the type cannot impact these traits' semantics, and
4363 // so they don't require it. This matches the comments on these traits in
4366 case UTT_IsVolatile:
4368 case UTT_IsUnsigned:
4370 // This type trait always returns false, checking the type is moot.
4371 case UTT_IsInterfaceClass:
4374 // C++14 [meta.unary.prop]:
4375 // If T is a non-union class type, T shall be a complete type.
4377 case UTT_IsPolymorphic:
4378 case UTT_IsAbstract:
4379 if (const auto *RD = ArgTy->getAsCXXRecordDecl())
4381 return !S.RequireCompleteType(
4382 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4385 // C++14 [meta.unary.prop]:
4386 // If T is a class type, T shall be a complete type.
4389 if (ArgTy->getAsCXXRecordDecl())
4390 return !S.RequireCompleteType(
4391 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4394 // C++1z [meta.unary.prop]:
4395 // remove_all_extents_t<T> shall be a complete type or cv void.
4396 case UTT_IsAggregate:
4398 case UTT_IsTriviallyCopyable:
4399 case UTT_IsStandardLayout:
4402 // Per the GCC type traits documentation, T shall be a complete type, cv void,
4403 // or an array of unknown bound. But GCC actually imposes the same constraints
4405 case UTT_HasNothrowAssign:
4406 case UTT_HasNothrowMoveAssign:
4407 case UTT_HasNothrowConstructor:
4408 case UTT_HasNothrowCopy:
4409 case UTT_HasTrivialAssign:
4410 case UTT_HasTrivialMoveAssign:
4411 case UTT_HasTrivialDefaultConstructor:
4412 case UTT_HasTrivialMoveConstructor:
4413 case UTT_HasTrivialCopy:
4414 case UTT_HasTrivialDestructor:
4415 case UTT_HasVirtualDestructor:
4416 ArgTy = QualType(ArgTy->getBaseElementTypeUnsafe(), 0);
4419 // C++1z [meta.unary.prop]:
4420 // T shall be a complete type, cv void, or an array of unknown bound.
4421 case UTT_IsDestructible:
4422 case UTT_IsNothrowDestructible:
4423 case UTT_IsTriviallyDestructible:
4424 case UTT_HasUniqueObjectRepresentations:
4425 if (ArgTy->isIncompleteArrayType() || ArgTy->isVoidType())
4428 return !S.RequireCompleteType(
4429 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4433 static bool HasNoThrowOperator(const RecordType *RT, OverloadedOperatorKind Op,
4434 Sema &Self, SourceLocation KeyLoc, ASTContext &C,
4435 bool (CXXRecordDecl::*HasTrivial)() const,
4436 bool (CXXRecordDecl::*HasNonTrivial)() const,
4437 bool (CXXMethodDecl::*IsDesiredOp)() const)
4439 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
4440 if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)())
4443 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op);
4444 DeclarationNameInfo NameInfo(Name, KeyLoc);
4445 LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName);
4446 if (Self.LookupQualifiedName(Res, RD)) {
4447 bool FoundOperator = false;
4448 Res.suppressDiagnostics();
4449 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end();
4450 Op != OpEnd; ++Op) {
4451 if (isa<FunctionTemplateDecl>(*Op))
4454 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op);
4455 if((Operator->*IsDesiredOp)()) {
4456 FoundOperator = true;
4457 const FunctionProtoType *CPT =
4458 Operator->getType()->getAs<FunctionProtoType>();
4459 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4460 if (!CPT || !CPT->isNothrow())
4464 return FoundOperator;
4469 static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
4470 SourceLocation KeyLoc, QualType T) {
4471 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
4473 ASTContext &C = Self.Context;
4475 default: llvm_unreachable("not a UTT");
4476 // Type trait expressions corresponding to the primary type category
4477 // predicates in C++0x [meta.unary.cat].
4479 return T->isVoidType();
4480 case UTT_IsIntegral:
4481 return T->isIntegralType(C);
4482 case UTT_IsFloatingPoint:
4483 return T->isFloatingType();
4485 return T->isArrayType();
4487 return T->isPointerType();
4488 case UTT_IsLvalueReference:
4489 return T->isLValueReferenceType();
4490 case UTT_IsRvalueReference:
4491 return T->isRValueReferenceType();
4492 case UTT_IsMemberFunctionPointer:
4493 return T->isMemberFunctionPointerType();
4494 case UTT_IsMemberObjectPointer:
4495 return T->isMemberDataPointerType();
4497 return T->isEnumeralType();
4499 return T->isUnionType();
4501 return T->isClassType() || T->isStructureType() || T->isInterfaceType();
4502 case UTT_IsFunction:
4503 return T->isFunctionType();
4505 // Type trait expressions which correspond to the convenient composition
4506 // predicates in C++0x [meta.unary.comp].
4507 case UTT_IsReference:
4508 return T->isReferenceType();
4509 case UTT_IsArithmetic:
4510 return T->isArithmeticType() && !T->isEnumeralType();
4511 case UTT_IsFundamental:
4512 return T->isFundamentalType();
4514 return T->isObjectType();
4516 // Note: semantic analysis depends on Objective-C lifetime types to be
4517 // considered scalar types. However, such types do not actually behave
4518 // like scalar types at run time (since they may require retain/release
4519 // operations), so we report them as non-scalar.
4520 if (T->isObjCLifetimeType()) {
4521 switch (T.getObjCLifetime()) {
4522 case Qualifiers::OCL_None:
4523 case Qualifiers::OCL_ExplicitNone:
4526 case Qualifiers::OCL_Strong:
4527 case Qualifiers::OCL_Weak:
4528 case Qualifiers::OCL_Autoreleasing:
4533 return T->isScalarType();
4534 case UTT_IsCompound:
4535 return T->isCompoundType();
4536 case UTT_IsMemberPointer:
4537 return T->isMemberPointerType();
4539 // Type trait expressions which correspond to the type property predicates
4540 // in C++0x [meta.unary.prop].
4542 return T.isConstQualified();
4543 case UTT_IsVolatile:
4544 return T.isVolatileQualified();
4546 return T.isTrivialType(C);
4547 case UTT_IsTriviallyCopyable:
4548 return T.isTriviallyCopyableType(C);
4549 case UTT_IsStandardLayout:
4550 return T->isStandardLayoutType();
4552 return T.isPODType(C);
4554 return T->isLiteralType(C);
4556 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4557 return !RD->isUnion() && RD->isEmpty();
4559 case UTT_IsPolymorphic:
4560 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4561 return !RD->isUnion() && RD->isPolymorphic();
4563 case UTT_IsAbstract:
4564 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4565 return !RD->isUnion() && RD->isAbstract();
4567 case UTT_IsAggregate:
4568 // Report vector extensions and complex types as aggregates because they
4569 // support aggregate initialization. GCC mirrors this behavior for vectors
4570 // but not _Complex.
4571 return T->isAggregateType() || T->isVectorType() || T->isExtVectorType() ||
4572 T->isAnyComplexType();
4573 // __is_interface_class only returns true when CL is invoked in /CLR mode and
4574 // even then only when it is used with the 'interface struct ...' syntax
4575 // Clang doesn't support /CLR which makes this type trait moot.
4576 case UTT_IsInterfaceClass:
4580 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4581 return RD->hasAttr<FinalAttr>();
4584 return T->isSignedIntegerType();
4585 case UTT_IsUnsigned:
4586 return T->isUnsignedIntegerType();
4588 // Type trait expressions which query classes regarding their construction,
4589 // destruction, and copying. Rather than being based directly on the
4590 // related type predicates in the standard, they are specified by both
4591 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those
4594 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
4595 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4597 // Note that these builtins do not behave as documented in g++: if a class
4598 // has both a trivial and a non-trivial special member of a particular kind,
4599 // they return false! For now, we emulate this behavior.
4600 // FIXME: This appears to be a g++ bug: more complex cases reveal that it
4601 // does not correctly compute triviality in the presence of multiple special
4602 // members of the same kind. Revisit this once the g++ bug is fixed.
4603 case UTT_HasTrivialDefaultConstructor:
4604 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4605 // If __is_pod (type) is true then the trait is true, else if type is
4606 // a cv class or union type (or array thereof) with a trivial default
4607 // constructor ([class.ctor]) then the trait is true, else it is false.
4610 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4611 return RD->hasTrivialDefaultConstructor() &&
4612 !RD->hasNonTrivialDefaultConstructor();
4614 case UTT_HasTrivialMoveConstructor:
4615 // This trait is implemented by MSVC 2012 and needed to parse the
4616 // standard library headers. Specifically this is used as the logic
4617 // behind std::is_trivially_move_constructible (20.9.4.3).
4620 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4621 return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor();
4623 case UTT_HasTrivialCopy:
4624 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4625 // If __is_pod (type) is true or type is a reference type then
4626 // the trait is true, else if type is a cv class or union type
4627 // with a trivial copy constructor ([class.copy]) then the trait
4628 // is true, else it is false.
4629 if (T.isPODType(C) || T->isReferenceType())
4631 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4632 return RD->hasTrivialCopyConstructor() &&
4633 !RD->hasNonTrivialCopyConstructor();
4635 case UTT_HasTrivialMoveAssign:
4636 // This trait is implemented by MSVC 2012 and needed to parse the
4637 // standard library headers. Specifically it is used as the logic
4638 // behind std::is_trivially_move_assignable (20.9.4.3)
4641 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4642 return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment();
4644 case UTT_HasTrivialAssign:
4645 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4646 // If type is const qualified or is a reference type then the
4647 // trait is false. Otherwise if __is_pod (type) is true then the
4648 // trait is true, else if type is a cv class or union type with
4649 // a trivial copy assignment ([class.copy]) then the trait is
4650 // true, else it is false.
4651 // Note: the const and reference restrictions are interesting,
4652 // given that const and reference members don't prevent a class
4653 // from having a trivial copy assignment operator (but do cause
4654 // errors if the copy assignment operator is actually used, q.v.
4655 // [class.copy]p12).
4657 if (T.isConstQualified())
4661 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4662 return RD->hasTrivialCopyAssignment() &&
4663 !RD->hasNonTrivialCopyAssignment();
4665 case UTT_IsDestructible:
4666 case UTT_IsTriviallyDestructible:
4667 case UTT_IsNothrowDestructible:
4668 // C++14 [meta.unary.prop]:
4669 // For reference types, is_destructible<T>::value is true.
4670 if (T->isReferenceType())
4673 // Objective-C++ ARC: autorelease types don't require destruction.
4674 if (T->isObjCLifetimeType() &&
4675 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
4678 // C++14 [meta.unary.prop]:
4679 // For incomplete types and function types, is_destructible<T>::value is
4681 if (T->isIncompleteType() || T->isFunctionType())
4684 // A type that requires destruction (via a non-trivial destructor or ARC
4685 // lifetime semantics) is not trivially-destructible.
4686 if (UTT == UTT_IsTriviallyDestructible && T.isDestructedType())
4689 // C++14 [meta.unary.prop]:
4690 // For object types and given U equal to remove_all_extents_t<T>, if the
4691 // expression std::declval<U&>().~U() is well-formed when treated as an
4692 // unevaluated operand (Clause 5), then is_destructible<T>::value is true
4693 if (auto *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
4694 CXXDestructorDecl *Destructor = Self.LookupDestructor(RD);
4697 // C++14 [dcl.fct.def.delete]p2:
4698 // A program that refers to a deleted function implicitly or
4699 // explicitly, other than to declare it, is ill-formed.
4700 if (Destructor->isDeleted())
4702 if (C.getLangOpts().AccessControl && Destructor->getAccess() != AS_public)
4704 if (UTT == UTT_IsNothrowDestructible) {
4705 const FunctionProtoType *CPT =
4706 Destructor->getType()->getAs<FunctionProtoType>();
4707 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4708 if (!CPT || !CPT->isNothrow())
4714 case UTT_HasTrivialDestructor:
4715 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
4716 // If __is_pod (type) is true or type is a reference type
4717 // then the trait is true, else if type is a cv class or union
4718 // type (or array thereof) with a trivial destructor
4719 // ([class.dtor]) then the trait is true, else it is
4721 if (T.isPODType(C) || T->isReferenceType())
4724 // Objective-C++ ARC: autorelease types don't require destruction.
4725 if (T->isObjCLifetimeType() &&
4726 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
4729 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4730 return RD->hasTrivialDestructor();
4732 // TODO: Propagate nothrowness for implicitly declared special members.
4733 case UTT_HasNothrowAssign:
4734 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4735 // If type is const qualified or is a reference type then the
4736 // trait is false. Otherwise if __has_trivial_assign (type)
4737 // is true then the trait is true, else if type is a cv class
4738 // or union type with copy assignment operators that are known
4739 // not to throw an exception then the trait is true, else it is
4741 if (C.getBaseElementType(T).isConstQualified())
4743 if (T->isReferenceType())
4745 if (T.isPODType(C) || T->isObjCLifetimeType())
4748 if (const RecordType *RT = T->getAs<RecordType>())
4749 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
4750 &CXXRecordDecl::hasTrivialCopyAssignment,
4751 &CXXRecordDecl::hasNonTrivialCopyAssignment,
4752 &CXXMethodDecl::isCopyAssignmentOperator);
4754 case UTT_HasNothrowMoveAssign:
4755 // This trait is implemented by MSVC 2012 and needed to parse the
4756 // standard library headers. Specifically this is used as the logic
4757 // behind std::is_nothrow_move_assignable (20.9.4.3).
4761 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>())
4762 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
4763 &CXXRecordDecl::hasTrivialMoveAssignment,
4764 &CXXRecordDecl::hasNonTrivialMoveAssignment,
4765 &CXXMethodDecl::isMoveAssignmentOperator);
4767 case UTT_HasNothrowCopy:
4768 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4769 // If __has_trivial_copy (type) is true then the trait is true, else
4770 // if type is a cv class or union type with copy constructors that are
4771 // known not to throw an exception then the trait is true, else it is
4773 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
4775 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
4776 if (RD->hasTrivialCopyConstructor() &&
4777 !RD->hasNonTrivialCopyConstructor())
4780 bool FoundConstructor = false;
4782 for (const auto *ND : Self.LookupConstructors(RD)) {
4783 // A template constructor is never a copy constructor.
4784 // FIXME: However, it may actually be selected at the actual overload
4785 // resolution point.
4786 if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
4788 // UsingDecl itself is not a constructor
4789 if (isa<UsingDecl>(ND))
4791 auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
4792 if (Constructor->isCopyConstructor(FoundTQs)) {
4793 FoundConstructor = true;
4794 const FunctionProtoType *CPT
4795 = Constructor->getType()->getAs<FunctionProtoType>();
4796 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4799 // TODO: check whether evaluating default arguments can throw.
4800 // For now, we'll be conservative and assume that they can throw.
4801 if (!CPT->isNothrow() || CPT->getNumParams() > 1)
4806 return FoundConstructor;
4809 case UTT_HasNothrowConstructor:
4810 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
4811 // If __has_trivial_constructor (type) is true then the trait is
4812 // true, else if type is a cv class or union type (or array
4813 // thereof) with a default constructor that is known not to
4814 // throw an exception then the trait is true, else it is false.
4815 if (T.isPODType(C) || T->isObjCLifetimeType())
4817 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
4818 if (RD->hasTrivialDefaultConstructor() &&
4819 !RD->hasNonTrivialDefaultConstructor())
4822 bool FoundConstructor = false;
4823 for (const auto *ND : Self.LookupConstructors(RD)) {
4824 // FIXME: In C++0x, a constructor template can be a default constructor.
4825 if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
4827 // UsingDecl itself is not a constructor
4828 if (isa<UsingDecl>(ND))
4830 auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
4831 if (Constructor->isDefaultConstructor()) {
4832 FoundConstructor = true;
4833 const FunctionProtoType *CPT
4834 = Constructor->getType()->getAs<FunctionProtoType>();
4835 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4838 // FIXME: check whether evaluating default arguments can throw.
4839 // For now, we'll be conservative and assume that they can throw.
4840 if (!CPT->isNothrow() || CPT->getNumParams() > 0)
4844 return FoundConstructor;
4847 case UTT_HasVirtualDestructor:
4848 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4849 // If type is a class type with a virtual destructor ([class.dtor])
4850 // then the trait is true, else it is false.
4851 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4852 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
4853 return Destructor->isVirtual();
4856 // These type trait expressions are modeled on the specifications for the
4857 // Embarcadero C++0x type trait functions:
4858 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4859 case UTT_IsCompleteType:
4860 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_):
4861 // Returns True if and only if T is a complete type at the point of the
4863 return !T->isIncompleteType();
4864 case UTT_HasUniqueObjectRepresentations:
4865 return C.hasUniqueObjectRepresentations(T);
4869 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
4870 QualType RhsT, SourceLocation KeyLoc);
4872 static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc,
4873 ArrayRef<TypeSourceInfo *> Args,
4874 SourceLocation RParenLoc) {
4875 if (Kind <= UTT_Last)
4876 return EvaluateUnaryTypeTrait(S, Kind, KWLoc, Args[0]->getType());
4878 // Evaluate BTT_ReferenceBindsToTemporary alongside the IsConstructible
4879 // traits to avoid duplication.
4880 if (Kind <= BTT_Last && Kind != BTT_ReferenceBindsToTemporary)
4881 return EvaluateBinaryTypeTrait(S, Kind, Args[0]->getType(),
4882 Args[1]->getType(), RParenLoc);
4885 case clang::BTT_ReferenceBindsToTemporary:
4886 case clang::TT_IsConstructible:
4887 case clang::TT_IsNothrowConstructible:
4888 case clang::TT_IsTriviallyConstructible: {
4889 // C++11 [meta.unary.prop]:
4890 // is_trivially_constructible is defined as:
4892 // is_constructible<T, Args...>::value is true and the variable
4893 // definition for is_constructible, as defined below, is known to call
4894 // no operation that is not trivial.
4896 // The predicate condition for a template specialization
4897 // is_constructible<T, Args...> shall be satisfied if and only if the
4898 // following variable definition would be well-formed for some invented
4901 // T t(create<Args>()...);
4902 assert(!Args.empty());
4904 // Precondition: T and all types in the parameter pack Args shall be
4905 // complete types, (possibly cv-qualified) void, or arrays of
4907 for (const auto *TSI : Args) {
4908 QualType ArgTy = TSI->getType();
4909 if (ArgTy->isVoidType() || ArgTy->isIncompleteArrayType())
4912 if (S.RequireCompleteType(KWLoc, ArgTy,
4913 diag::err_incomplete_type_used_in_type_trait_expr))
4917 // Make sure the first argument is not incomplete nor a function type.
4918 QualType T = Args[0]->getType();
4919 if (T->isIncompleteType() || T->isFunctionType())
4922 // Make sure the first argument is not an abstract type.
4923 CXXRecordDecl *RD = T->getAsCXXRecordDecl();
4924 if (RD && RD->isAbstract())
4927 SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs;
4928 SmallVector<Expr *, 2> ArgExprs;
4929 ArgExprs.reserve(Args.size() - 1);
4930 for (unsigned I = 1, N = Args.size(); I != N; ++I) {
4931 QualType ArgTy = Args[I]->getType();
4932 if (ArgTy->isObjectType() || ArgTy->isFunctionType())
4933 ArgTy = S.Context.getRValueReferenceType(ArgTy);
4934 OpaqueArgExprs.push_back(
4935 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(),
4936 ArgTy.getNonLValueExprType(S.Context),
4937 Expr::getValueKindForType(ArgTy)));
4939 for (Expr &E : OpaqueArgExprs)
4940 ArgExprs.push_back(&E);
4942 // Perform the initialization in an unevaluated context within a SFINAE
4943 // trap at translation unit scope.
4944 EnterExpressionEvaluationContext Unevaluated(
4945 S, Sema::ExpressionEvaluationContext::Unevaluated);
4946 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
4947 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl());
4948 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0]));
4949 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc,
4951 InitializationSequence Init(S, To, InitKind, ArgExprs);
4955 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs);
4956 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
4959 if (Kind == clang::TT_IsConstructible)
4962 if (Kind == clang::BTT_ReferenceBindsToTemporary) {
4963 if (!T->isReferenceType())
4966 return !Init.isDirectReferenceBinding();
4969 if (Kind == clang::TT_IsNothrowConstructible)
4970 return S.canThrow(Result.get()) == CT_Cannot;
4972 if (Kind == clang::TT_IsTriviallyConstructible) {
4973 // Under Objective-C ARC and Weak, if the destination has non-trivial
4974 // Objective-C lifetime, this is a non-trivial construction.
4975 if (T.getNonReferenceType().hasNonTrivialObjCLifetime())
4978 // The initialization succeeded; now make sure there are no non-trivial
4980 return !Result.get()->hasNonTrivialCall(S.Context);
4983 llvm_unreachable("unhandled type trait");
4986 default: llvm_unreachable("not a TT");
4992 ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4993 ArrayRef<TypeSourceInfo *> Args,
4994 SourceLocation RParenLoc) {
4995 QualType ResultType = Context.getLogicalOperationType();
4997 if (Kind <= UTT_Last && !CheckUnaryTypeTraitTypeCompleteness(
4998 *this, Kind, KWLoc, Args[0]->getType()))
5001 bool Dependent = false;
5002 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
5003 if (Args[I]->getType()->isDependentType()) {
5009 bool Result = false;
5011 Result = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc);
5013 return TypeTraitExpr::Create(Context, ResultType, KWLoc, Kind, Args,
5017 ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
5018 ArrayRef<ParsedType> Args,
5019 SourceLocation RParenLoc) {
5020 SmallVector<TypeSourceInfo *, 4> ConvertedArgs;
5021 ConvertedArgs.reserve(Args.size());
5023 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
5024 TypeSourceInfo *TInfo;
5025 QualType T = GetTypeFromParser(Args[I], &TInfo);
5027 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc);
5029 ConvertedArgs.push_back(TInfo);
5032 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc);
5035 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
5036 QualType RhsT, SourceLocation KeyLoc) {
5037 assert(!LhsT->isDependentType() && !RhsT->isDependentType() &&
5038 "Cannot evaluate traits of dependent types");
5041 case BTT_IsBaseOf: {
5042 // C++0x [meta.rel]p2
5043 // Base is a base class of Derived without regard to cv-qualifiers or
5044 // Base and Derived are not unions and name the same class type without
5045 // regard to cv-qualifiers.
5047 const RecordType *lhsRecord = LhsT->getAs<RecordType>();
5048 const RecordType *rhsRecord = RhsT->getAs<RecordType>();
5049 if (!rhsRecord || !lhsRecord) {
5050 const ObjCObjectType *LHSObjTy = LhsT->getAs<ObjCObjectType>();
5051 const ObjCObjectType *RHSObjTy = RhsT->getAs<ObjCObjectType>();
5052 if (!LHSObjTy || !RHSObjTy)
5055 ObjCInterfaceDecl *BaseInterface = LHSObjTy->getInterface();
5056 ObjCInterfaceDecl *DerivedInterface = RHSObjTy->getInterface();
5057 if (!BaseInterface || !DerivedInterface)
5060 if (Self.RequireCompleteType(
5061 KeyLoc, RhsT, diag::err_incomplete_type_used_in_type_trait_expr))
5064 return BaseInterface->isSuperClassOf(DerivedInterface);
5067 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT)
5068 == (lhsRecord == rhsRecord));
5070 if (lhsRecord == rhsRecord)
5071 return !lhsRecord->getDecl()->isUnion();
5073 // C++0x [meta.rel]p2:
5074 // If Base and Derived are class types and are different types
5075 // (ignoring possible cv-qualifiers) then Derived shall be a
5077 if (Self.RequireCompleteType(KeyLoc, RhsT,
5078 diag::err_incomplete_type_used_in_type_trait_expr))
5081 return cast<CXXRecordDecl>(rhsRecord->getDecl())
5082 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl()));
5085 return Self.Context.hasSameType(LhsT, RhsT);
5086 case BTT_TypeCompatible: {
5087 // GCC ignores cv-qualifiers on arrays for this builtin.
5088 Qualifiers LhsQuals, RhsQuals;
5089 QualType Lhs = Self.getASTContext().getUnqualifiedArrayType(LhsT, LhsQuals);
5090 QualType Rhs = Self.getASTContext().getUnqualifiedArrayType(RhsT, RhsQuals);
5091 return Self.Context.typesAreCompatible(Lhs, Rhs);
5093 case BTT_IsConvertible:
5094 case BTT_IsConvertibleTo: {
5095 // C++0x [meta.rel]p4:
5096 // Given the following function prototype:
5098 // template <class T>
5099 // typename add_rvalue_reference<T>::type create();
5101 // the predicate condition for a template specialization
5102 // is_convertible<From, To> shall be satisfied if and only if
5103 // the return expression in the following code would be
5104 // well-formed, including any implicit conversions to the return
5105 // type of the function:
5108 // return create<From>();
5111 // Access checking is performed as if in a context unrelated to To and
5112 // From. Only the validity of the immediate context of the expression
5113 // of the return-statement (including conversions to the return type)
5116 // We model the initialization as a copy-initialization of a temporary
5117 // of the appropriate type, which for this expression is identical to the
5118 // return statement (since NRVO doesn't apply).
5120 // Functions aren't allowed to return function or array types.
5121 if (RhsT->isFunctionType() || RhsT->isArrayType())
5124 // A return statement in a void function must have void type.
5125 if (RhsT->isVoidType())
5126 return LhsT->isVoidType();
5128 // A function definition requires a complete, non-abstract return type.
5129 if (!Self.isCompleteType(KeyLoc, RhsT) || Self.isAbstractType(KeyLoc, RhsT))
5132 // Compute the result of add_rvalue_reference.
5133 if (LhsT->isObjectType() || LhsT->isFunctionType())
5134 LhsT = Self.Context.getRValueReferenceType(LhsT);
5136 // Build a fake source and destination for initialization.
5137 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT));
5138 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
5139 Expr::getValueKindForType(LhsT));
5140 Expr *FromPtr = &From;
5141 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc,
5144 // Perform the initialization in an unevaluated context within a SFINAE
5145 // trap at translation unit scope.
5146 EnterExpressionEvaluationContext Unevaluated(
5147 Self, Sema::ExpressionEvaluationContext::Unevaluated);
5148 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
5149 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
5150 InitializationSequence Init(Self, To, Kind, FromPtr);
5154 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr);
5155 return !Result.isInvalid() && !SFINAE.hasErrorOccurred();
5158 case BTT_IsAssignable:
5159 case BTT_IsNothrowAssignable:
5160 case BTT_IsTriviallyAssignable: {
5161 // C++11 [meta.unary.prop]p3:
5162 // is_trivially_assignable is defined as:
5163 // is_assignable<T, U>::value is true and the assignment, as defined by
5164 // is_assignable, is known to call no operation that is not trivial
5166 // is_assignable is defined as:
5167 // The expression declval<T>() = declval<U>() is well-formed when
5168 // treated as an unevaluated operand (Clause 5).
5170 // For both, T and U shall be complete types, (possibly cv-qualified)
5171 // void, or arrays of unknown bound.
5172 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() &&
5173 Self.RequireCompleteType(KeyLoc, LhsT,
5174 diag::err_incomplete_type_used_in_type_trait_expr))
5176 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() &&
5177 Self.RequireCompleteType(KeyLoc, RhsT,
5178 diag::err_incomplete_type_used_in_type_trait_expr))
5181 // cv void is never assignable.
5182 if (LhsT->isVoidType() || RhsT->isVoidType())
5185 // Build expressions that emulate the effect of declval<T>() and
5187 if (LhsT->isObjectType() || LhsT->isFunctionType())
5188 LhsT = Self.Context.getRValueReferenceType(LhsT);
5189 if (RhsT->isObjectType() || RhsT->isFunctionType())
5190 RhsT = Self.Context.getRValueReferenceType(RhsT);
5191 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
5192 Expr::getValueKindForType(LhsT));
5193 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context),
5194 Expr::getValueKindForType(RhsT));
5196 // Attempt the assignment in an unevaluated context within a SFINAE
5197 // trap at translation unit scope.
5198 EnterExpressionEvaluationContext Unevaluated(
5199 Self, Sema::ExpressionEvaluationContext::Unevaluated);
5200 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
5201 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
5202 ExprResult Result = Self.BuildBinOp(/*S=*/nullptr, KeyLoc, BO_Assign, &Lhs,
5204 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
5207 if (BTT == BTT_IsAssignable)
5210 if (BTT == BTT_IsNothrowAssignable)
5211 return Self.canThrow(Result.get()) == CT_Cannot;
5213 if (BTT == BTT_IsTriviallyAssignable) {
5214 // Under Objective-C ARC and Weak, if the destination has non-trivial
5215 // Objective-C lifetime, this is a non-trivial assignment.
5216 if (LhsT.getNonReferenceType().hasNonTrivialObjCLifetime())
5219 return !Result.get()->hasNonTrivialCall(Self.Context);
5222 llvm_unreachable("unhandled type trait");
5225 default: llvm_unreachable("not a BTT");
5227 llvm_unreachable("Unknown type trait or not implemented");
5230 ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT,
5231 SourceLocation KWLoc,
5234 SourceLocation RParen) {
5235 TypeSourceInfo *TSInfo;
5236 QualType T = GetTypeFromParser(Ty, &TSInfo);
5238 TSInfo = Context.getTrivialTypeSourceInfo(T);
5240 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen);
5243 static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT,
5244 QualType T, Expr *DimExpr,
5245 SourceLocation KeyLoc) {
5246 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
5250 if (T->isArrayType()) {
5252 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
5254 T = AT->getElementType();
5260 case ATT_ArrayExtent: {
5263 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value,
5264 diag::err_dimension_expr_not_constant_integer,
5267 if (Value.isSigned() && Value.isNegative()) {
5268 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer)
5269 << DimExpr->getSourceRange();
5272 Dim = Value.getLimitedValue();
5274 if (T->isArrayType()) {
5276 bool Matched = false;
5277 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
5283 T = AT->getElementType();
5286 if (Matched && T->isArrayType()) {
5287 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T))
5288 return CAT->getSize().getLimitedValue();
5294 llvm_unreachable("Unknown type trait or not implemented");
5297 ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT,
5298 SourceLocation KWLoc,
5299 TypeSourceInfo *TSInfo,
5301 SourceLocation RParen) {
5302 QualType T = TSInfo->getType();
5304 // FIXME: This should likely be tracked as an APInt to remove any host
5305 // assumptions about the width of size_t on the target.
5307 if (!T->isDependentType())
5308 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc);
5310 // While the specification for these traits from the Embarcadero C++
5311 // compiler's documentation says the return type is 'unsigned int', Clang
5312 // returns 'size_t'. On Windows, the primary platform for the Embarcadero
5313 // compiler, there is no difference. On several other platforms this is an
5314 // important distinction.
5315 return new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, DimExpr,
5316 RParen, Context.getSizeType());
5319 ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET,
5320 SourceLocation KWLoc,
5322 SourceLocation RParen) {
5323 // If error parsing the expression, ignore.
5327 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen);
5332 static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) {
5334 case ET_IsLValueExpr: return E->isLValue();
5335 case ET_IsRValueExpr: return E->isRValue();
5337 llvm_unreachable("Expression trait not covered by switch");
5340 ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET,
5341 SourceLocation KWLoc,
5343 SourceLocation RParen) {
5344 if (Queried->isTypeDependent()) {
5345 // Delay type-checking for type-dependent expressions.
5346 } else if (Queried->getType()->isPlaceholderType()) {
5347 ExprResult PE = CheckPlaceholderExpr(Queried);
5348 if (PE.isInvalid()) return ExprError();
5349 return BuildExpressionTrait(ET, KWLoc, PE.get(), RParen);
5352 bool Value = EvaluateExpressionTrait(ET, Queried);
5354 return new (Context)
5355 ExpressionTraitExpr(KWLoc, ET, Queried, Value, RParen, Context.BoolTy);
5358 QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS,
5362 assert(!LHS.get()->getType()->isPlaceholderType() &&
5363 !RHS.get()->getType()->isPlaceholderType() &&
5364 "placeholders should have been weeded out by now");
5366 // The LHS undergoes lvalue conversions if this is ->*, and undergoes the
5367 // temporary materialization conversion otherwise.
5369 LHS = DefaultLvalueConversion(LHS.get());
5370 else if (LHS.get()->isRValue())
5371 LHS = TemporaryMaterializationConversion(LHS.get());
5372 if (LHS.isInvalid())
5375 // The RHS always undergoes lvalue conversions.
5376 RHS = DefaultLvalueConversion(RHS.get());
5377 if (RHS.isInvalid()) return QualType();
5379 const char *OpSpelling = isIndirect ? "->*" : ".*";
5381 // The binary operator .* [p3: ->*] binds its second operand, which shall
5382 // be of type "pointer to member of T" (where T is a completely-defined
5383 // class type) [...]
5384 QualType RHSType = RHS.get()->getType();
5385 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>();
5387 Diag(Loc, diag::err_bad_memptr_rhs)
5388 << OpSpelling << RHSType << RHS.get()->getSourceRange();
5392 QualType Class(MemPtr->getClass(), 0);
5394 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the
5395 // member pointer points must be completely-defined. However, there is no
5396 // reason for this semantic distinction, and the rule is not enforced by
5397 // other compilers. Therefore, we do not check this property, as it is
5398 // likely to be considered a defect.
5401 // [...] to its first operand, which shall be of class T or of a class of
5402 // which T is an unambiguous and accessible base class. [p3: a pointer to
5404 QualType LHSType = LHS.get()->getType();
5406 if (const PointerType *Ptr = LHSType->getAs<PointerType>())
5407 LHSType = Ptr->getPointeeType();
5409 Diag(Loc, diag::err_bad_memptr_lhs)
5410 << OpSpelling << 1 << LHSType
5411 << FixItHint::CreateReplacement(SourceRange(Loc), ".*");
5416 if (!Context.hasSameUnqualifiedType(Class, LHSType)) {
5417 // If we want to check the hierarchy, we need a complete type.
5418 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs,
5419 OpSpelling, (int)isIndirect)) {
5423 if (!IsDerivedFrom(Loc, LHSType, Class)) {
5424 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling
5425 << (int)isIndirect << LHS.get()->getType();
5429 CXXCastPath BasePath;
5430 if (CheckDerivedToBaseConversion(LHSType, Class, Loc,
5431 SourceRange(LHS.get()->getLocStart(),
5432 RHS.get()->getLocEnd()),
5436 // Cast LHS to type of use.
5437 QualType UseType = Context.getQualifiedType(Class, LHSType.getQualifiers());
5439 UseType = Context.getPointerType(UseType);
5440 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind();
5441 LHS = ImpCastExprToType(LHS.get(), UseType, CK_DerivedToBase, VK,
5445 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) {
5446 // Diagnose use of pointer-to-member type which when used as
5447 // the functional cast in a pointer-to-member expression.
5448 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect;
5453 // The result is an object or a function of the type specified by the
5455 // The cv qualifiers are the union of those in the pointer and the left side,
5456 // in accordance with 5.5p5 and 5.2.5.
5457 QualType Result = MemPtr->getPointeeType();
5458 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers());
5460 // C++0x [expr.mptr.oper]p6:
5461 // In a .* expression whose object expression is an rvalue, the program is
5462 // ill-formed if the second operand is a pointer to member function with
5463 // ref-qualifier &. In a ->* expression or in a .* expression whose object
5464 // expression is an lvalue, the program is ill-formed if the second operand
5465 // is a pointer to member function with ref-qualifier &&.
5466 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) {
5467 switch (Proto->getRefQualifier()) {
5473 if (!isIndirect && !LHS.get()->Classify(Context).isLValue()) {
5474 // C++2a allows functions with ref-qualifier & if their cv-qualifier-seq
5475 // is (exactly) 'const'.
5476 if (Proto->isConst() && !Proto->isVolatile())
5477 Diag(Loc, getLangOpts().CPlusPlus2a
5478 ? diag::warn_cxx17_compat_pointer_to_const_ref_member_on_rvalue
5479 : diag::ext_pointer_to_const_ref_member_on_rvalue);
5481 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
5482 << RHSType << 1 << LHS.get()->getSourceRange();
5487 if (isIndirect || !LHS.get()->Classify(Context).isRValue())
5488 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
5489 << RHSType << 0 << LHS.get()->getSourceRange();
5494 // C++ [expr.mptr.oper]p6:
5495 // The result of a .* expression whose second operand is a pointer
5496 // to a data member is of the same value category as its
5497 // first operand. The result of a .* expression whose second
5498 // operand is a pointer to a member function is a prvalue. The
5499 // result of an ->* expression is an lvalue if its second operand
5500 // is a pointer to data member and a prvalue otherwise.
5501 if (Result->isFunctionType()) {
5503 return Context.BoundMemberTy;
5504 } else if (isIndirect) {
5507 VK = LHS.get()->getValueKind();
5513 /// Try to convert a type to another according to C++11 5.16p3.
5515 /// This is part of the parameter validation for the ? operator. If either
5516 /// value operand is a class type, the two operands are attempted to be
5517 /// converted to each other. This function does the conversion in one direction.
5518 /// It returns true if the program is ill-formed and has already been diagnosed
5520 static bool TryClassUnification(Sema &Self, Expr *From, Expr *To,
5521 SourceLocation QuestionLoc,
5522 bool &HaveConversion,
5524 HaveConversion = false;
5525 ToType = To->getType();
5527 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(),
5530 // The process for determining whether an operand expression E1 of type T1
5531 // can be converted to match an operand expression E2 of type T2 is defined
5533 // -- If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
5534 // implicitly converted to type "lvalue reference to T2", subject to the
5535 // constraint that in the conversion the reference must bind directly to
5537 // -- If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
5538 // implicitly converted to the type "rvalue reference to R2", subject to
5539 // the constraint that the reference must bind directly.
5540 if (To->isLValue() || To->isXValue()) {
5541 QualType T = To->isLValue() ? Self.Context.getLValueReferenceType(ToType)
5542 : Self.Context.getRValueReferenceType(ToType);
5544 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
5546 InitializationSequence InitSeq(Self, Entity, Kind, From);
5547 if (InitSeq.isDirectReferenceBinding()) {
5549 HaveConversion = true;
5553 if (InitSeq.isAmbiguous())
5554 return InitSeq.Diagnose(Self, Entity, Kind, From);
5557 // -- If E2 is an rvalue, or if the conversion above cannot be done:
5558 // -- if E1 and E2 have class type, and the underlying class types are
5559 // the same or one is a base class of the other:
5560 QualType FTy = From->getType();
5561 QualType TTy = To->getType();
5562 const RecordType *FRec = FTy->getAs<RecordType>();
5563 const RecordType *TRec = TTy->getAs<RecordType>();
5564 bool FDerivedFromT = FRec && TRec && FRec != TRec &&
5565 Self.IsDerivedFrom(QuestionLoc, FTy, TTy);
5566 if (FRec && TRec && (FRec == TRec || FDerivedFromT ||
5567 Self.IsDerivedFrom(QuestionLoc, TTy, FTy))) {
5568 // E1 can be converted to match E2 if the class of T2 is the
5569 // same type as, or a base class of, the class of T1, and
5571 if (FRec == TRec || FDerivedFromT) {
5572 if (TTy.isAtLeastAsQualifiedAs(FTy)) {
5573 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
5574 InitializationSequence InitSeq(Self, Entity, Kind, From);
5576 HaveConversion = true;
5580 if (InitSeq.isAmbiguous())
5581 return InitSeq.Diagnose(Self, Entity, Kind, From);
5588 // -- Otherwise: E1 can be converted to match E2 if E1 can be
5589 // implicitly converted to the type that expression E2 would have
5590 // if E2 were converted to an rvalue (or the type it has, if E2 is
5593 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not
5594 // to the array-to-pointer or function-to-pointer conversions.
5595 TTy = TTy.getNonLValueExprType(Self.Context);
5597 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
5598 InitializationSequence InitSeq(Self, Entity, Kind, From);
5599 HaveConversion = !InitSeq.Failed();
5601 if (InitSeq.isAmbiguous())
5602 return InitSeq.Diagnose(Self, Entity, Kind, From);
5607 /// Try to find a common type for two according to C++0x 5.16p5.
5609 /// This is part of the parameter validation for the ? operator. If either
5610 /// value operand is a class type, overload resolution is used to find a
5611 /// conversion to a common type.
5612 static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS,
5613 SourceLocation QuestionLoc) {
5614 Expr *Args[2] = { LHS.get(), RHS.get() };
5615 OverloadCandidateSet CandidateSet(QuestionLoc,
5616 OverloadCandidateSet::CSK_Operator);
5617 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args,
5620 OverloadCandidateSet::iterator Best;
5621 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) {
5623 // We found a match. Perform the conversions on the arguments and move on.
5624 ExprResult LHSRes = Self.PerformImplicitConversion(
5625 LHS.get(), Best->BuiltinParamTypes[0], Best->Conversions[0],
5626 Sema::AA_Converting);
5627 if (LHSRes.isInvalid())
5631 ExprResult RHSRes = Self.PerformImplicitConversion(
5632 RHS.get(), Best->BuiltinParamTypes[1], Best->Conversions[1],
5633 Sema::AA_Converting);
5634 if (RHSRes.isInvalid())
5638 Self.MarkFunctionReferenced(QuestionLoc, Best->Function);
5642 case OR_No_Viable_Function:
5644 // Emit a better diagnostic if one of the expressions is a null pointer
5645 // constant and the other is a pointer type. In this case, the user most
5646 // likely forgot to take the address of the other expression.
5647 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
5650 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
5651 << LHS.get()->getType() << RHS.get()->getType()
5652 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5656 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl)
5657 << LHS.get()->getType() << RHS.get()->getType()
5658 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5659 // FIXME: Print the possible common types by printing the return types of
5660 // the viable candidates.
5664 llvm_unreachable("Conditional operator has only built-in overloads");
5669 /// Perform an "extended" implicit conversion as returned by
5670 /// TryClassUnification.
5671 static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) {
5672 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
5673 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(),
5675 Expr *Arg = E.get();
5676 InitializationSequence InitSeq(Self, Entity, Kind, Arg);
5677 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, Arg);
5678 if (Result.isInvalid())
5685 /// Check the operands of ?: under C++ semantics.
5687 /// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y
5688 /// extension. In this case, LHS == Cond. (But they're not aliases.)
5689 QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
5690 ExprResult &RHS, ExprValueKind &VK,
5692 SourceLocation QuestionLoc) {
5693 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++
5694 // interface pointers.
5696 // C++11 [expr.cond]p1
5697 // The first expression is contextually converted to bool.
5699 // FIXME; GCC's vector extension permits the use of a?b:c where the type of
5700 // a is that of a integer vector with the same number of elements and
5701 // size as the vectors of b and c. If one of either b or c is a scalar
5702 // it is implicitly converted to match the type of the vector.
5703 // Otherwise the expression is ill-formed. If both b and c are scalars,
5704 // then b and c are checked and converted to the type of a if possible.
5705 // Unlike the OpenCL ?: operator, the expression is evaluated as
5706 // (a[0] != 0 ? b[0] : c[0], .. , a[n] != 0 ? b[n] : c[n]).
5707 if (!Cond.get()->isTypeDependent()) {
5708 ExprResult CondRes = CheckCXXBooleanCondition(Cond.get());
5709 if (CondRes.isInvalid())
5718 // Either of the arguments dependent?
5719 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent())
5720 return Context.DependentTy;
5722 // C++11 [expr.cond]p2
5723 // If either the second or the third operand has type (cv) void, ...
5724 QualType LTy = LHS.get()->getType();
5725 QualType RTy = RHS.get()->getType();
5726 bool LVoid = LTy->isVoidType();
5727 bool RVoid = RTy->isVoidType();
5728 if (LVoid || RVoid) {
5729 // ... one of the following shall hold:
5730 // -- The second or the third operand (but not both) is a (possibly
5731 // parenthesized) throw-expression; the result is of the type
5732 // and value category of the other.
5733 bool LThrow = isa<CXXThrowExpr>(LHS.get()->IgnoreParenImpCasts());
5734 bool RThrow = isa<CXXThrowExpr>(RHS.get()->IgnoreParenImpCasts());
5735 if (LThrow != RThrow) {
5736 Expr *NonThrow = LThrow ? RHS.get() : LHS.get();
5737 VK = NonThrow->getValueKind();
5738 // DR (no number yet): the result is a bit-field if the
5739 // non-throw-expression operand is a bit-field.
5740 OK = NonThrow->getObjectKind();
5741 return NonThrow->getType();
5744 // -- Both the second and third operands have type void; the result is of
5745 // type void and is a prvalue.
5747 return Context.VoidTy;
5749 // Neither holds, error.
5750 Diag(QuestionLoc, diag::err_conditional_void_nonvoid)
5751 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1)
5752 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5758 // C++11 [expr.cond]p3
5759 // Otherwise, if the second and third operand have different types, and
5760 // either has (cv) class type [...] an attempt is made to convert each of
5761 // those operands to the type of the other.
5762 if (!Context.hasSameType(LTy, RTy) &&
5763 (LTy->isRecordType() || RTy->isRecordType())) {
5764 // These return true if a single direction is already ambiguous.
5765 QualType L2RType, R2LType;
5766 bool HaveL2R, HaveR2L;
5767 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType))
5769 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType))
5772 // If both can be converted, [...] the program is ill-formed.
5773 if (HaveL2R && HaveR2L) {
5774 Diag(QuestionLoc, diag::err_conditional_ambiguous)
5775 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5779 // If exactly one conversion is possible, that conversion is applied to
5780 // the chosen operand and the converted operands are used in place of the
5781 // original operands for the remainder of this section.
5783 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid())
5785 LTy = LHS.get()->getType();
5786 } else if (HaveR2L) {
5787 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid())
5789 RTy = RHS.get()->getType();
5793 // C++11 [expr.cond]p3
5794 // if both are glvalues of the same value category and the same type except
5795 // for cv-qualification, an attempt is made to convert each of those
5796 // operands to the type of the other.
5798 // Resolving a defect in P0012R1: we extend this to cover all cases where
5799 // one of the operands is reference-compatible with the other, in order
5800 // to support conditionals between functions differing in noexcept.
5801 ExprValueKind LVK = LHS.get()->getValueKind();
5802 ExprValueKind RVK = RHS.get()->getValueKind();
5803 if (!Context.hasSameType(LTy, RTy) &&
5804 LVK == RVK && LVK != VK_RValue) {
5805 // DerivedToBase was already handled by the class-specific case above.
5806 // FIXME: Should we allow ObjC conversions here?
5807 bool DerivedToBase, ObjCConversion, ObjCLifetimeConversion;
5808 if (CompareReferenceRelationship(
5809 QuestionLoc, LTy, RTy, DerivedToBase,
5810 ObjCConversion, ObjCLifetimeConversion) == Ref_Compatible &&
5811 !DerivedToBase && !ObjCConversion && !ObjCLifetimeConversion &&
5812 // [...] subject to the constraint that the reference must bind
5814 !RHS.get()->refersToBitField() &&
5815 !RHS.get()->refersToVectorElement()) {
5816 RHS = ImpCastExprToType(RHS.get(), LTy, CK_NoOp, RVK);
5817 RTy = RHS.get()->getType();
5818 } else if (CompareReferenceRelationship(
5819 QuestionLoc, RTy, LTy, DerivedToBase,
5820 ObjCConversion, ObjCLifetimeConversion) == Ref_Compatible &&
5821 !DerivedToBase && !ObjCConversion && !ObjCLifetimeConversion &&
5822 !LHS.get()->refersToBitField() &&
5823 !LHS.get()->refersToVectorElement()) {
5824 LHS = ImpCastExprToType(LHS.get(), RTy, CK_NoOp, LVK);
5825 LTy = LHS.get()->getType();
5829 // C++11 [expr.cond]p4
5830 // If the second and third operands are glvalues of the same value
5831 // category and have the same type, the result is of that type and
5832 // value category and it is a bit-field if the second or the third
5833 // operand is a bit-field, or if both are bit-fields.
5834 // We only extend this to bitfields, not to the crazy other kinds of
5836 bool Same = Context.hasSameType(LTy, RTy);
5837 if (Same && LVK == RVK && LVK != VK_RValue &&
5838 LHS.get()->isOrdinaryOrBitFieldObject() &&
5839 RHS.get()->isOrdinaryOrBitFieldObject()) {
5840 VK = LHS.get()->getValueKind();
5841 if (LHS.get()->getObjectKind() == OK_BitField ||
5842 RHS.get()->getObjectKind() == OK_BitField)
5845 // If we have function pointer types, unify them anyway to unify their
5846 // exception specifications, if any.
5847 if (LTy->isFunctionPointerType() || LTy->isMemberFunctionPointerType()) {
5848 Qualifiers Qs = LTy.getQualifiers();
5849 LTy = FindCompositePointerType(QuestionLoc, LHS, RHS,
5850 /*ConvertArgs*/false);
5851 LTy = Context.getQualifiedType(LTy, Qs);
5853 assert(!LTy.isNull() && "failed to find composite pointer type for "
5854 "canonically equivalent function ptr types");
5855 assert(Context.hasSameType(LTy, RTy) && "bad composite pointer type");
5861 // C++11 [expr.cond]p5
5862 // Otherwise, the result is a prvalue. If the second and third operands
5863 // do not have the same type, and either has (cv) class type, ...
5864 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) {
5865 // ... overload resolution is used to determine the conversions (if any)
5866 // to be applied to the operands. If the overload resolution fails, the
5867 // program is ill-formed.
5868 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc))
5872 // C++11 [expr.cond]p6
5873 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard
5874 // conversions are performed on the second and third operands.
5875 LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
5876 RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
5877 if (LHS.isInvalid() || RHS.isInvalid())
5879 LTy = LHS.get()->getType();
5880 RTy = RHS.get()->getType();
5882 // After those conversions, one of the following shall hold:
5883 // -- The second and third operands have the same type; the result
5884 // is of that type. If the operands have class type, the result
5885 // is a prvalue temporary of the result type, which is
5886 // copy-initialized from either the second operand or the third
5887 // operand depending on the value of the first operand.
5888 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) {
5889 if (LTy->isRecordType()) {
5890 // The operands have class type. Make a temporary copy.
5891 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy);
5893 ExprResult LHSCopy = PerformCopyInitialization(Entity,
5896 if (LHSCopy.isInvalid())
5899 ExprResult RHSCopy = PerformCopyInitialization(Entity,
5902 if (RHSCopy.isInvalid())
5909 // If we have function pointer types, unify them anyway to unify their
5910 // exception specifications, if any.
5911 if (LTy->isFunctionPointerType() || LTy->isMemberFunctionPointerType()) {
5912 LTy = FindCompositePointerType(QuestionLoc, LHS, RHS);
5913 assert(!LTy.isNull() && "failed to find composite pointer type for "
5914 "canonically equivalent function ptr types");
5920 // Extension: conditional operator involving vector types.
5921 if (LTy->isVectorType() || RTy->isVectorType())
5922 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false,
5923 /*AllowBothBool*/true,
5924 /*AllowBoolConversions*/false);
5926 // -- The second and third operands have arithmetic or enumeration type;
5927 // the usual arithmetic conversions are performed to bring them to a
5928 // common type, and the result is of that type.
5929 if (LTy->isArithmeticType() && RTy->isArithmeticType()) {
5930 QualType ResTy = UsualArithmeticConversions(LHS, RHS);
5931 if (LHS.isInvalid() || RHS.isInvalid())
5933 if (ResTy.isNull()) {
5935 diag::err_typecheck_cond_incompatible_operands) << LTy << RTy
5936 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5940 LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
5941 RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
5946 // -- The second and third operands have pointer type, or one has pointer
5947 // type and the other is a null pointer constant, or both are null
5948 // pointer constants, at least one of which is non-integral; pointer
5949 // conversions and qualification conversions are performed to bring them
5950 // to their composite pointer type. The result is of the composite
5952 // -- The second and third operands have pointer to member type, or one has
5953 // pointer to member type and the other is a null pointer constant;
5954 // pointer to member conversions and qualification conversions are
5955 // performed to bring them to a common type, whose cv-qualification
5956 // shall match the cv-qualification of either the second or the third
5957 // operand. The result is of the common type.
5958 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS);
5959 if (!Composite.isNull())
5962 // Similarly, attempt to find composite type of two objective-c pointers.
5963 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc);
5964 if (!Composite.isNull())
5967 // Check if we are using a null with a non-pointer type.
5968 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
5971 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
5972 << LHS.get()->getType() << RHS.get()->getType()
5973 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5977 static FunctionProtoType::ExceptionSpecInfo
5978 mergeExceptionSpecs(Sema &S, FunctionProtoType::ExceptionSpecInfo ESI1,
5979 FunctionProtoType::ExceptionSpecInfo ESI2,
5980 SmallVectorImpl<QualType> &ExceptionTypeStorage) {
5981 ExceptionSpecificationType EST1 = ESI1.Type;
5982 ExceptionSpecificationType EST2 = ESI2.Type;
5984 // If either of them can throw anything, that is the result.
5985 if (EST1 == EST_None) return ESI1;
5986 if (EST2 == EST_None) return ESI2;
5987 if (EST1 == EST_MSAny) return ESI1;
5988 if (EST2 == EST_MSAny) return ESI2;
5989 if (EST1 == EST_NoexceptFalse) return ESI1;
5990 if (EST2 == EST_NoexceptFalse) return ESI2;
5992 // If either of them is non-throwing, the result is the other.
5993 if (EST1 == EST_DynamicNone) return ESI2;
5994 if (EST2 == EST_DynamicNone) return ESI1;
5995 if (EST1 == EST_BasicNoexcept) return ESI2;
5996 if (EST2 == EST_BasicNoexcept) return ESI1;
5997 if (EST1 == EST_NoexceptTrue) return ESI2;
5998 if (EST2 == EST_NoexceptTrue) return ESI1;
6000 // If we're left with value-dependent computed noexcept expressions, we're
6001 // stuck. Before C++17, we can just drop the exception specification entirely,
6002 // since it's not actually part of the canonical type. And this should never
6003 // happen in C++17, because it would mean we were computing the composite
6004 // pointer type of dependent types, which should never happen.
6005 if (EST1 == EST_DependentNoexcept || EST2 == EST_DependentNoexcept) {
6006 assert(!S.getLangOpts().CPlusPlus17 &&
6007 "computing composite pointer type of dependent types");
6008 return FunctionProtoType::ExceptionSpecInfo();
6011 // Switch over the possibilities so that people adding new values know to
6012 // update this function.
6015 case EST_DynamicNone:
6017 case EST_BasicNoexcept:
6018 case EST_DependentNoexcept:
6019 case EST_NoexceptFalse:
6020 case EST_NoexceptTrue:
6021 llvm_unreachable("handled above");
6024 // This is the fun case: both exception specifications are dynamic. Form
6025 // the union of the two lists.
6026 assert(EST2 == EST_Dynamic && "other cases should already be handled");
6027 llvm::SmallPtrSet<QualType, 8> Found;
6028 for (auto &Exceptions : {ESI1.Exceptions, ESI2.Exceptions})
6029 for (QualType E : Exceptions)
6030 if (Found.insert(S.Context.getCanonicalType(E)).second)
6031 ExceptionTypeStorage.push_back(E);
6033 FunctionProtoType::ExceptionSpecInfo Result(EST_Dynamic);
6034 Result.Exceptions = ExceptionTypeStorage;
6038 case EST_Unevaluated:
6039 case EST_Uninstantiated:
6041 llvm_unreachable("shouldn't see unresolved exception specifications here");
6044 llvm_unreachable("invalid ExceptionSpecificationType");
6047 /// Find a merged pointer type and convert the two expressions to it.
6049 /// This finds the composite pointer type (or member pointer type) for @p E1
6050 /// and @p E2 according to C++1z 5p14. It converts both expressions to this
6051 /// type and returns it.
6052 /// It does not emit diagnostics.
6054 /// \param Loc The location of the operator requiring these two expressions to
6055 /// be converted to the composite pointer type.
6057 /// \param ConvertArgs If \c false, do not convert E1 and E2 to the target type.
6058 QualType Sema::FindCompositePointerType(SourceLocation Loc,
6059 Expr *&E1, Expr *&E2,
6061 assert(getLangOpts().CPlusPlus && "This function assumes C++");
6064 // The composite pointer type of two operands p1 and p2 having types T1
6066 QualType T1 = E1->getType(), T2 = E2->getType();
6068 // where at least one is a pointer or pointer to member type or
6069 // std::nullptr_t is:
6070 bool T1IsPointerLike = T1->isAnyPointerType() || T1->isMemberPointerType() ||
6071 T1->isNullPtrType();
6072 bool T2IsPointerLike = T2->isAnyPointerType() || T2->isMemberPointerType() ||
6073 T2->isNullPtrType();
6074 if (!T1IsPointerLike && !T2IsPointerLike)
6077 // - if both p1 and p2 are null pointer constants, std::nullptr_t;
6078 // This can't actually happen, following the standard, but we also use this
6079 // to implement the end of [expr.conv], which hits this case.
6081 // - if either p1 or p2 is a null pointer constant, T2 or T1, respectively;
6082 if (T1IsPointerLike &&
6083 E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
6085 E2 = ImpCastExprToType(E2, T1, T1->isMemberPointerType()
6086 ? CK_NullToMemberPointer
6087 : CK_NullToPointer).get();
6090 if (T2IsPointerLike &&
6091 E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
6093 E1 = ImpCastExprToType(E1, T2, T2->isMemberPointerType()
6094 ? CK_NullToMemberPointer
6095 : CK_NullToPointer).get();
6099 // Now both have to be pointers or member pointers.
6100 if (!T1IsPointerLike || !T2IsPointerLike)
6102 assert(!T1->isNullPtrType() && !T2->isNullPtrType() &&
6103 "nullptr_t should be a null pointer constant");
6105 // - if T1 or T2 is "pointer to cv1 void" and the other type is
6106 // "pointer to cv2 T", "pointer to cv12 void", where cv12 is
6107 // the union of cv1 and cv2;
6108 // - if T1 or T2 is "pointer to noexcept function" and the other type is
6109 // "pointer to function", where the function types are otherwise the same,
6110 // "pointer to function";
6111 // FIXME: This rule is defective: it should also permit removing noexcept
6112 // from a pointer to member function. As a Clang extension, we also
6113 // permit removing 'noreturn', so we generalize this rule to;
6114 // - [Clang] If T1 and T2 are both of type "pointer to function" or
6115 // "pointer to member function" and the pointee types can be unified
6116 // by a function pointer conversion, that conversion is applied
6117 // before checking the following rules.
6118 // - if T1 is "pointer to cv1 C1" and T2 is "pointer to cv2 C2", where C1
6119 // is reference-related to C2 or C2 is reference-related to C1 (8.6.3),
6120 // the cv-combined type of T1 and T2 or the cv-combined type of T2 and T1,
6122 // - if T1 is "pointer to member of C1 of type cv1 U1" and T2 is "pointer
6123 // to member of C2 of type cv2 U2" where C1 is reference-related to C2 or
6124 // C2 is reference-related to C1 (8.6.3), the cv-combined type of T2 and
6125 // T1 or the cv-combined type of T1 and T2, respectively;
6126 // - if T1 and T2 are similar types (4.5), the cv-combined type of T1 and
6129 // If looked at in the right way, these bullets all do the same thing.
6130 // What we do here is, we build the two possible cv-combined types, and try
6131 // the conversions in both directions. If only one works, or if the two
6132 // composite types are the same, we have succeeded.
6133 // FIXME: extended qualifiers?
6135 // Note that this will fail to find a composite pointer type for "pointer
6136 // to void" and "pointer to function". We can't actually perform the final
6137 // conversion in this case, even though a composite pointer type formally
6139 SmallVector<unsigned, 4> QualifierUnion;
6140 SmallVector<std::pair<const Type *, const Type *>, 4> MemberOfClass;
6141 QualType Composite1 = T1;
6142 QualType Composite2 = T2;
6143 unsigned NeedConstBefore = 0;
6145 const PointerType *Ptr1, *Ptr2;
6146 if ((Ptr1 = Composite1->getAs<PointerType>()) &&
6147 (Ptr2 = Composite2->getAs<PointerType>())) {
6148 Composite1 = Ptr1->getPointeeType();
6149 Composite2 = Ptr2->getPointeeType();
6151 // If we're allowed to create a non-standard composite type, keep track
6152 // of where we need to fill in additional 'const' qualifiers.
6153 if (Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
6154 NeedConstBefore = QualifierUnion.size();
6156 QualifierUnion.push_back(
6157 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
6158 MemberOfClass.push_back(std::make_pair(nullptr, nullptr));
6162 const MemberPointerType *MemPtr1, *MemPtr2;
6163 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) &&
6164 (MemPtr2 = Composite2->getAs<MemberPointerType>())) {
6165 Composite1 = MemPtr1->getPointeeType();
6166 Composite2 = MemPtr2->getPointeeType();
6168 // If we're allowed to create a non-standard composite type, keep track
6169 // of where we need to fill in additional 'const' qualifiers.
6170 if (Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
6171 NeedConstBefore = QualifierUnion.size();
6173 QualifierUnion.push_back(
6174 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
6175 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(),
6176 MemPtr2->getClass()));
6180 // FIXME: block pointer types?
6182 // Cannot unwrap any more types.
6186 // Apply the function pointer conversion to unify the types. We've already
6187 // unwrapped down to the function types, and we want to merge rather than
6188 // just convert, so do this ourselves rather than calling
6189 // IsFunctionConversion.
6191 // FIXME: In order to match the standard wording as closely as possible, we
6192 // currently only do this under a single level of pointers. Ideally, we would
6193 // allow this in general, and set NeedConstBefore to the relevant depth on
6194 // the side(s) where we changed anything.
6195 if (QualifierUnion.size() == 1) {
6196 if (auto *FPT1 = Composite1->getAs<FunctionProtoType>()) {
6197 if (auto *FPT2 = Composite2->getAs<FunctionProtoType>()) {
6198 FunctionProtoType::ExtProtoInfo EPI1 = FPT1->getExtProtoInfo();
6199 FunctionProtoType::ExtProtoInfo EPI2 = FPT2->getExtProtoInfo();
6201 // The result is noreturn if both operands are.
6203 EPI1.ExtInfo.getNoReturn() && EPI2.ExtInfo.getNoReturn();
6204 EPI1.ExtInfo = EPI1.ExtInfo.withNoReturn(Noreturn);
6205 EPI2.ExtInfo = EPI2.ExtInfo.withNoReturn(Noreturn);
6207 // The result is nothrow if both operands are.
6208 SmallVector<QualType, 8> ExceptionTypeStorage;
6209 EPI1.ExceptionSpec = EPI2.ExceptionSpec =
6210 mergeExceptionSpecs(*this, EPI1.ExceptionSpec, EPI2.ExceptionSpec,
6211 ExceptionTypeStorage);
6213 Composite1 = Context.getFunctionType(FPT1->getReturnType(),
6214 FPT1->getParamTypes(), EPI1);
6215 Composite2 = Context.getFunctionType(FPT2->getReturnType(),
6216 FPT2->getParamTypes(), EPI2);
6221 if (NeedConstBefore) {
6222 // Extension: Add 'const' to qualifiers that come before the first qualifier
6223 // mismatch, so that our (non-standard!) composite type meets the
6224 // requirements of C++ [conv.qual]p4 bullet 3.
6225 for (unsigned I = 0; I != NeedConstBefore; ++I)
6226 if ((QualifierUnion[I] & Qualifiers::Const) == 0)
6227 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const;
6230 // Rewrap the composites as pointers or member pointers with the union CVRs.
6231 auto MOC = MemberOfClass.rbegin();
6232 for (unsigned CVR : llvm::reverse(QualifierUnion)) {
6233 Qualifiers Quals = Qualifiers::fromCVRMask(CVR);
6234 auto Classes = *MOC++;
6235 if (Classes.first && Classes.second) {
6236 // Rebuild member pointer type
6237 Composite1 = Context.getMemberPointerType(
6238 Context.getQualifiedType(Composite1, Quals), Classes.first);
6239 Composite2 = Context.getMemberPointerType(
6240 Context.getQualifiedType(Composite2, Quals), Classes.second);
6242 // Rebuild pointer type
6244 Context.getPointerType(Context.getQualifiedType(Composite1, Quals));
6246 Context.getPointerType(Context.getQualifiedType(Composite2, Quals));
6254 InitializedEntity Entity;
6255 InitializationKind Kind;
6256 InitializationSequence E1ToC, E2ToC;
6259 Conversion(Sema &S, SourceLocation Loc, Expr *&E1, Expr *&E2,
6261 : S(S), E1(E1), E2(E2), Composite(Composite),
6262 Entity(InitializedEntity::InitializeTemporary(Composite)),
6263 Kind(InitializationKind::CreateCopy(Loc, SourceLocation())),
6264 E1ToC(S, Entity, Kind, E1), E2ToC(S, Entity, Kind, E2),
6265 Viable(E1ToC && E2ToC) {}
6268 ExprResult E1Result = E1ToC.Perform(S, Entity, Kind, E1);
6269 if (E1Result.isInvalid())
6271 E1 = E1Result.getAs<Expr>();
6273 ExprResult E2Result = E2ToC.Perform(S, Entity, Kind, E2);
6274 if (E2Result.isInvalid())
6276 E2 = E2Result.getAs<Expr>();
6282 // Try to convert to each composite pointer type.
6283 Conversion C1(*this, Loc, E1, E2, Composite1);
6284 if (C1.Viable && Context.hasSameType(Composite1, Composite2)) {
6285 if (ConvertArgs && C1.perform())
6287 return C1.Composite;
6289 Conversion C2(*this, Loc, E1, E2, Composite2);
6291 if (C1.Viable == C2.Viable) {
6292 // Either Composite1 and Composite2 are viable and are different, or
6293 // neither is viable.
6294 // FIXME: How both be viable and different?
6298 // Convert to the chosen type.
6299 if (ConvertArgs && (C1.Viable ? C1 : C2).perform())
6302 return C1.Viable ? C1.Composite : C2.Composite;
6305 ExprResult Sema::MaybeBindToTemporary(Expr *E) {
6309 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?");
6311 // If the result is a glvalue, we shouldn't bind it.
6315 // In ARC, calls that return a retainable type can return retained,
6316 // in which case we have to insert a consuming cast.
6317 if (getLangOpts().ObjCAutoRefCount &&
6318 E->getType()->isObjCRetainableType()) {
6320 bool ReturnsRetained;
6322 // For actual calls, we compute this by examining the type of the
6324 if (CallExpr *Call = dyn_cast<CallExpr>(E)) {
6325 Expr *Callee = Call->getCallee()->IgnoreParens();
6326 QualType T = Callee->getType();
6328 if (T == Context.BoundMemberTy) {
6329 // Handle pointer-to-members.
6330 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee))
6331 T = BinOp->getRHS()->getType();
6332 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee))
6333 T = Mem->getMemberDecl()->getType();
6336 if (const PointerType *Ptr = T->getAs<PointerType>())
6337 T = Ptr->getPointeeType();
6338 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>())
6339 T = Ptr->getPointeeType();
6340 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>())
6341 T = MemPtr->getPointeeType();
6343 const FunctionType *FTy = T->getAs<FunctionType>();
6344 assert(FTy && "call to value not of function type?");
6345 ReturnsRetained = FTy->getExtInfo().getProducesResult();
6347 // ActOnStmtExpr arranges things so that StmtExprs of retainable
6348 // type always produce a +1 object.
6349 } else if (isa<StmtExpr>(E)) {
6350 ReturnsRetained = true;
6352 // We hit this case with the lambda conversion-to-block optimization;
6353 // we don't want any extra casts here.
6354 } else if (isa<CastExpr>(E) &&
6355 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) {
6358 // For message sends and property references, we try to find an
6359 // actual method. FIXME: we should infer retention by selector in
6360 // cases where we don't have an actual method.
6362 ObjCMethodDecl *D = nullptr;
6363 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) {
6364 D = Send->getMethodDecl();
6365 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) {
6366 D = BoxedExpr->getBoxingMethod();
6367 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) {
6368 // Don't do reclaims if we're using the zero-element array
6370 if (ArrayLit->getNumElements() == 0 &&
6371 Context.getLangOpts().ObjCRuntime.hasEmptyCollections())
6374 D = ArrayLit->getArrayWithObjectsMethod();
6375 } else if (ObjCDictionaryLiteral *DictLit
6376 = dyn_cast<ObjCDictionaryLiteral>(E)) {
6377 // Don't do reclaims if we're using the zero-element dictionary
6379 if (DictLit->getNumElements() == 0 &&
6380 Context.getLangOpts().ObjCRuntime.hasEmptyCollections())
6383 D = DictLit->getDictWithObjectsMethod();
6386 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>());
6388 // Don't do reclaims on performSelector calls; despite their
6389 // return type, the invoked method doesn't necessarily actually
6390 // return an object.
6391 if (!ReturnsRetained &&
6392 D && D->getMethodFamily() == OMF_performSelector)
6396 // Don't reclaim an object of Class type.
6397 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType())
6400 Cleanup.setExprNeedsCleanups(true);
6402 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject
6403 : CK_ARCReclaimReturnedObject);
6404 return ImplicitCastExpr::Create(Context, E->getType(), ck, E, nullptr,
6408 if (!getLangOpts().CPlusPlus)
6411 // Search for the base element type (cf. ASTContext::getBaseElementType) with
6412 // a fast path for the common case that the type is directly a RecordType.
6413 const Type *T = Context.getCanonicalType(E->getType().getTypePtr());
6414 const RecordType *RT = nullptr;
6416 switch (T->getTypeClass()) {
6418 RT = cast<RecordType>(T);
6420 case Type::ConstantArray:
6421 case Type::IncompleteArray:
6422 case Type::VariableArray:
6423 case Type::DependentSizedArray:
6424 T = cast<ArrayType>(T)->getElementType().getTypePtr();
6431 // That should be enough to guarantee that this type is complete, if we're
6432 // not processing a decltype expression.
6433 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
6434 if (RD->isInvalidDecl() || RD->isDependentContext())
6437 bool IsDecltype = ExprEvalContexts.back().ExprContext ==
6438 ExpressionEvaluationContextRecord::EK_Decltype;
6439 CXXDestructorDecl *Destructor = IsDecltype ? nullptr : LookupDestructor(RD);
6442 MarkFunctionReferenced(E->getExprLoc(), Destructor);
6443 CheckDestructorAccess(E->getExprLoc(), Destructor,
6444 PDiag(diag::err_access_dtor_temp)
6446 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
6449 // If destructor is trivial, we can avoid the extra copy.
6450 if (Destructor->isTrivial())
6453 // We need a cleanup, but we don't need to remember the temporary.
6454 Cleanup.setExprNeedsCleanups(true);
6457 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor);
6458 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E);
6461 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind);
6467 Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) {
6468 if (SubExpr.isInvalid())
6471 return MaybeCreateExprWithCleanups(SubExpr.get());
6474 Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) {
6475 assert(SubExpr && "subexpression can't be null!");
6477 CleanupVarDeclMarking();
6479 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects;
6480 assert(ExprCleanupObjects.size() >= FirstCleanup);
6481 assert(Cleanup.exprNeedsCleanups() ||
6482 ExprCleanupObjects.size() == FirstCleanup);
6483 if (!Cleanup.exprNeedsCleanups())
6486 auto Cleanups = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup,
6487 ExprCleanupObjects.size() - FirstCleanup);
6489 auto *E = ExprWithCleanups::Create(
6490 Context, SubExpr, Cleanup.cleanupsHaveSideEffects(), Cleanups);
6491 DiscardCleanupsInEvaluationContext();
6496 Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) {
6497 assert(SubStmt && "sub-statement can't be null!");
6499 CleanupVarDeclMarking();
6501 if (!Cleanup.exprNeedsCleanups())
6504 // FIXME: In order to attach the temporaries, wrap the statement into
6505 // a StmtExpr; currently this is only used for asm statements.
6506 // This is hacky, either create a new CXXStmtWithTemporaries statement or
6507 // a new AsmStmtWithTemporaries.
6508 CompoundStmt *CompStmt = CompoundStmt::Create(
6509 Context, SubStmt, SourceLocation(), SourceLocation());
6510 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(),
6512 return MaybeCreateExprWithCleanups(E);
6515 /// Process the expression contained within a decltype. For such expressions,
6516 /// certain semantic checks on temporaries are delayed until this point, and
6517 /// are omitted for the 'topmost' call in the decltype expression. If the
6518 /// topmost call bound a temporary, strip that temporary off the expression.
6519 ExprResult Sema::ActOnDecltypeExpression(Expr *E) {
6520 assert(ExprEvalContexts.back().ExprContext ==
6521 ExpressionEvaluationContextRecord::EK_Decltype &&
6522 "not in a decltype expression");
6524 // C++11 [expr.call]p11:
6525 // If a function call is a prvalue of object type,
6526 // -- if the function call is either
6527 // -- the operand of a decltype-specifier, or
6528 // -- the right operand of a comma operator that is the operand of a
6529 // decltype-specifier,
6530 // a temporary object is not introduced for the prvalue.
6532 // Recursively rebuild ParenExprs and comma expressions to strip out the
6533 // outermost CXXBindTemporaryExpr, if any.
6534 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
6535 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr());
6536 if (SubExpr.isInvalid())
6538 if (SubExpr.get() == PE->getSubExpr())
6540 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.get());
6542 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
6543 if (BO->getOpcode() == BO_Comma) {
6544 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS());
6545 if (RHS.isInvalid())
6547 if (RHS.get() == BO->getRHS())
6549 return new (Context) BinaryOperator(
6550 BO->getLHS(), RHS.get(), BO_Comma, BO->getType(), BO->getValueKind(),
6551 BO->getObjectKind(), BO->getOperatorLoc(), BO->getFPFeatures());
6555 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E);
6556 CallExpr *TopCall = TopBind ? dyn_cast<CallExpr>(TopBind->getSubExpr())
6563 // Disable the special decltype handling now.
6564 ExprEvalContexts.back().ExprContext =
6565 ExpressionEvaluationContextRecord::EK_Other;
6567 // In MS mode, don't perform any extra checking of call return types within a
6568 // decltype expression.
6569 if (getLangOpts().MSVCCompat)
6572 // Perform the semantic checks we delayed until this point.
6573 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size();
6575 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I];
6576 if (Call == TopCall)
6579 if (CheckCallReturnType(Call->getCallReturnType(Context),
6580 Call->getLocStart(),
6581 Call, Call->getDirectCallee()))
6585 // Now all relevant types are complete, check the destructors are accessible
6586 // and non-deleted, and annotate them on the temporaries.
6587 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size();
6589 CXXBindTemporaryExpr *Bind =
6590 ExprEvalContexts.back().DelayedDecltypeBinds[I];
6591 if (Bind == TopBind)
6594 CXXTemporary *Temp = Bind->getTemporary();
6597 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
6598 CXXDestructorDecl *Destructor = LookupDestructor(RD);
6599 Temp->setDestructor(Destructor);
6601 MarkFunctionReferenced(Bind->getExprLoc(), Destructor);
6602 CheckDestructorAccess(Bind->getExprLoc(), Destructor,
6603 PDiag(diag::err_access_dtor_temp)
6604 << Bind->getType());
6605 if (DiagnoseUseOfDecl(Destructor, Bind->getExprLoc()))
6608 // We need a cleanup, but we don't need to remember the temporary.
6609 Cleanup.setExprNeedsCleanups(true);
6612 // Possibly strip off the top CXXBindTemporaryExpr.
6616 /// Note a set of 'operator->' functions that were used for a member access.
6617 static void noteOperatorArrows(Sema &S,
6618 ArrayRef<FunctionDecl *> OperatorArrows) {
6619 unsigned SkipStart = OperatorArrows.size(), SkipCount = 0;
6620 // FIXME: Make this configurable?
6622 if (OperatorArrows.size() > Limit) {
6623 // Produce Limit-1 normal notes and one 'skipping' note.
6624 SkipStart = (Limit - 1) / 2 + (Limit - 1) % 2;
6625 SkipCount = OperatorArrows.size() - (Limit - 1);
6628 for (unsigned I = 0; I < OperatorArrows.size(); /**/) {
6629 if (I == SkipStart) {
6630 S.Diag(OperatorArrows[I]->getLocation(),
6631 diag::note_operator_arrows_suppressed)
6635 S.Diag(OperatorArrows[I]->getLocation(), diag::note_operator_arrow_here)
6636 << OperatorArrows[I]->getCallResultType();
6642 ExprResult Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base,
6643 SourceLocation OpLoc,
6644 tok::TokenKind OpKind,
6645 ParsedType &ObjectType,
6646 bool &MayBePseudoDestructor) {
6647 // Since this might be a postfix expression, get rid of ParenListExprs.
6648 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base);
6649 if (Result.isInvalid()) return ExprError();
6650 Base = Result.get();
6652 Result = CheckPlaceholderExpr(Base);
6653 if (Result.isInvalid()) return ExprError();
6654 Base = Result.get();
6656 QualType BaseType = Base->getType();
6657 MayBePseudoDestructor = false;
6658 if (BaseType->isDependentType()) {
6659 // If we have a pointer to a dependent type and are using the -> operator,
6660 // the object type is the type that the pointer points to. We might still
6661 // have enough information about that type to do something useful.
6662 if (OpKind == tok::arrow)
6663 if (const PointerType *Ptr = BaseType->getAs<PointerType>())
6664 BaseType = Ptr->getPointeeType();
6666 ObjectType = ParsedType::make(BaseType);
6667 MayBePseudoDestructor = true;
6671 // C++ [over.match.oper]p8:
6672 // [...] When operator->returns, the operator-> is applied to the value
6673 // returned, with the original second operand.
6674 if (OpKind == tok::arrow) {
6675 QualType StartingType = BaseType;
6676 bool NoArrowOperatorFound = false;
6677 bool FirstIteration = true;
6678 FunctionDecl *CurFD = dyn_cast<FunctionDecl>(CurContext);
6679 // The set of types we've considered so far.
6680 llvm::SmallPtrSet<CanQualType,8> CTypes;
6681 SmallVector<FunctionDecl*, 8> OperatorArrows;
6682 CTypes.insert(Context.getCanonicalType(BaseType));
6684 while (BaseType->isRecordType()) {
6685 if (OperatorArrows.size() >= getLangOpts().ArrowDepth) {
6686 Diag(OpLoc, diag::err_operator_arrow_depth_exceeded)
6687 << StartingType << getLangOpts().ArrowDepth << Base->getSourceRange();
6688 noteOperatorArrows(*this, OperatorArrows);
6689 Diag(OpLoc, diag::note_operator_arrow_depth)
6690 << getLangOpts().ArrowDepth;
6694 Result = BuildOverloadedArrowExpr(
6696 // When in a template specialization and on the first loop iteration,
6697 // potentially give the default diagnostic (with the fixit in a
6698 // separate note) instead of having the error reported back to here
6699 // and giving a diagnostic with a fixit attached to the error itself.
6700 (FirstIteration && CurFD && CurFD->isFunctionTemplateSpecialization())
6702 : &NoArrowOperatorFound);
6703 if (Result.isInvalid()) {
6704 if (NoArrowOperatorFound) {
6705 if (FirstIteration) {
6706 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
6707 << BaseType << 1 << Base->getSourceRange()
6708 << FixItHint::CreateReplacement(OpLoc, ".");
6709 OpKind = tok::period;
6712 Diag(OpLoc, diag::err_typecheck_member_reference_arrow)
6713 << BaseType << Base->getSourceRange();
6714 CallExpr *CE = dyn_cast<CallExpr>(Base);
6715 if (Decl *CD = (CE ? CE->getCalleeDecl() : nullptr)) {
6716 Diag(CD->getLocStart(),
6717 diag::note_member_reference_arrow_from_operator_arrow);
6722 Base = Result.get();
6723 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base))
6724 OperatorArrows.push_back(OpCall->getDirectCallee());
6725 BaseType = Base->getType();
6726 CanQualType CBaseType = Context.getCanonicalType(BaseType);
6727 if (!CTypes.insert(CBaseType).second) {
6728 Diag(OpLoc, diag::err_operator_arrow_circular) << StartingType;
6729 noteOperatorArrows(*this, OperatorArrows);
6732 FirstIteration = false;
6735 if (OpKind == tok::arrow &&
6736 (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()))
6737 BaseType = BaseType->getPointeeType();
6740 // Objective-C properties allow "." access on Objective-C pointer types,
6741 // so adjust the base type to the object type itself.
6742 if (BaseType->isObjCObjectPointerType())
6743 BaseType = BaseType->getPointeeType();
6745 // C++ [basic.lookup.classref]p2:
6746 // [...] If the type of the object expression is of pointer to scalar
6747 // type, the unqualified-id is looked up in the context of the complete
6748 // postfix-expression.
6750 // This also indicates that we could be parsing a pseudo-destructor-name.
6751 // Note that Objective-C class and object types can be pseudo-destructor
6752 // expressions or normal member (ivar or property) access expressions, and
6753 // it's legal for the type to be incomplete if this is a pseudo-destructor
6754 // call. We'll do more incomplete-type checks later in the lookup process,
6755 // so just skip this check for ObjC types.
6756 if (BaseType->isObjCObjectOrInterfaceType()) {
6757 ObjectType = ParsedType::make(BaseType);
6758 MayBePseudoDestructor = true;
6760 } else if (!BaseType->isRecordType()) {
6761 ObjectType = nullptr;
6762 MayBePseudoDestructor = true;
6766 // The object type must be complete (or dependent), or
6767 // C++11 [expr.prim.general]p3:
6768 // Unlike the object expression in other contexts, *this is not required to
6769 // be of complete type for purposes of class member access (5.2.5) outside
6770 // the member function body.
6771 if (!BaseType->isDependentType() &&
6772 !isThisOutsideMemberFunctionBody(BaseType) &&
6773 RequireCompleteType(OpLoc, BaseType, diag::err_incomplete_member_access))
6776 // C++ [basic.lookup.classref]p2:
6777 // If the id-expression in a class member access (5.2.5) is an
6778 // unqualified-id, and the type of the object expression is of a class
6779 // type C (or of pointer to a class type C), the unqualified-id is looked
6780 // up in the scope of class C. [...]
6781 ObjectType = ParsedType::make(BaseType);
6785 static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base,
6786 tok::TokenKind& OpKind, SourceLocation OpLoc) {
6787 if (Base->hasPlaceholderType()) {
6788 ExprResult result = S.CheckPlaceholderExpr(Base);
6789 if (result.isInvalid()) return true;
6790 Base = result.get();
6792 ObjectType = Base->getType();
6794 // C++ [expr.pseudo]p2:
6795 // The left-hand side of the dot operator shall be of scalar type. The
6796 // left-hand side of the arrow operator shall be of pointer to scalar type.
6797 // This scalar type is the object type.
6798 // Note that this is rather different from the normal handling for the
6800 if (OpKind == tok::arrow) {
6801 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) {
6802 ObjectType = Ptr->getPointeeType();
6803 } else if (!Base->isTypeDependent()) {
6804 // The user wrote "p->" when they probably meant "p."; fix it.
6805 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
6806 << ObjectType << true
6807 << FixItHint::CreateReplacement(OpLoc, ".");
6808 if (S.isSFINAEContext())
6811 OpKind = tok::period;
6818 /// Check if it's ok to try and recover dot pseudo destructor calls on
6819 /// pointer objects.
6821 canRecoverDotPseudoDestructorCallsOnPointerObjects(Sema &SemaRef,
6822 QualType DestructedType) {
6823 // If this is a record type, check if its destructor is callable.
6824 if (auto *RD = DestructedType->getAsCXXRecordDecl()) {
6825 if (CXXDestructorDecl *D = SemaRef.LookupDestructor(RD))
6826 return SemaRef.CanUseDecl(D, /*TreatUnavailableAsInvalid=*/false);
6830 // Otherwise, check if it's a type for which it's valid to use a pseudo-dtor.
6831 return DestructedType->isDependentType() || DestructedType->isScalarType() ||
6832 DestructedType->isVectorType();
6835 ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base,
6836 SourceLocation OpLoc,
6837 tok::TokenKind OpKind,
6838 const CXXScopeSpec &SS,
6839 TypeSourceInfo *ScopeTypeInfo,
6840 SourceLocation CCLoc,
6841 SourceLocation TildeLoc,
6842 PseudoDestructorTypeStorage Destructed) {
6843 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo();
6845 QualType ObjectType;
6846 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6849 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() &&
6850 !ObjectType->isVectorType()) {
6851 if (getLangOpts().MSVCCompat && ObjectType->isVoidType())
6852 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange();
6854 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar)
6855 << ObjectType << Base->getSourceRange();
6860 // C++ [expr.pseudo]p2:
6861 // [...] The cv-unqualified versions of the object type and of the type
6862 // designated by the pseudo-destructor-name shall be the same type.
6863 if (DestructedTypeInfo) {
6864 QualType DestructedType = DestructedTypeInfo->getType();
6865 SourceLocation DestructedTypeStart
6866 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin();
6867 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) {
6868 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) {
6869 // Detect dot pseudo destructor calls on pointer objects, e.g.:
6872 if (OpKind == tok::period && ObjectType->isPointerType() &&
6873 Context.hasSameUnqualifiedType(DestructedType,
6874 ObjectType->getPointeeType())) {
6876 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
6877 << ObjectType << /*IsArrow=*/0 << Base->getSourceRange();
6879 // Issue a fixit only when the destructor is valid.
6880 if (canRecoverDotPseudoDestructorCallsOnPointerObjects(
6881 *this, DestructedType))
6882 Diagnostic << FixItHint::CreateReplacement(OpLoc, "->");
6884 // Recover by setting the object type to the destructed type and the
6885 // operator to '->'.
6886 ObjectType = DestructedType;
6887 OpKind = tok::arrow;
6889 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch)
6890 << ObjectType << DestructedType << Base->getSourceRange()
6891 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
6893 // Recover by setting the destructed type to the object type.
6894 DestructedType = ObjectType;
6895 DestructedTypeInfo =
6896 Context.getTrivialTypeSourceInfo(ObjectType, DestructedTypeStart);
6897 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6899 } else if (DestructedType.getObjCLifetime() !=
6900 ObjectType.getObjCLifetime()) {
6902 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) {
6903 // Okay: just pretend that the user provided the correctly-qualified
6906 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals)
6907 << ObjectType << DestructedType << Base->getSourceRange()
6908 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
6911 // Recover by setting the destructed type to the object type.
6912 DestructedType = ObjectType;
6913 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType,
6914 DestructedTypeStart);
6915 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6920 // C++ [expr.pseudo]p2:
6921 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the
6924 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name
6926 // shall designate the same scalar type.
6927 if (ScopeTypeInfo) {
6928 QualType ScopeType = ScopeTypeInfo->getType();
6929 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() &&
6930 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) {
6932 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(),
6933 diag::err_pseudo_dtor_type_mismatch)
6934 << ObjectType << ScopeType << Base->getSourceRange()
6935 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange();
6937 ScopeType = QualType();
6938 ScopeTypeInfo = nullptr;
6943 = new (Context) CXXPseudoDestructorExpr(Context, Base,
6944 OpKind == tok::arrow, OpLoc,
6945 SS.getWithLocInContext(Context),
6954 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
6955 SourceLocation OpLoc,
6956 tok::TokenKind OpKind,
6958 UnqualifiedId &FirstTypeName,
6959 SourceLocation CCLoc,
6960 SourceLocation TildeLoc,
6961 UnqualifiedId &SecondTypeName) {
6962 assert((FirstTypeName.getKind() == UnqualifiedIdKind::IK_TemplateId ||
6963 FirstTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) &&
6964 "Invalid first type name in pseudo-destructor");
6965 assert((SecondTypeName.getKind() == UnqualifiedIdKind::IK_TemplateId ||
6966 SecondTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) &&
6967 "Invalid second type name in pseudo-destructor");
6969 QualType ObjectType;
6970 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6973 // Compute the object type that we should use for name lookup purposes. Only
6974 // record types and dependent types matter.
6975 ParsedType ObjectTypePtrForLookup;
6977 if (ObjectType->isRecordType())
6978 ObjectTypePtrForLookup = ParsedType::make(ObjectType);
6979 else if (ObjectType->isDependentType())
6980 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy);
6983 // Convert the name of the type being destructed (following the ~) into a
6984 // type (with source-location information).
6985 QualType DestructedType;
6986 TypeSourceInfo *DestructedTypeInfo = nullptr;
6987 PseudoDestructorTypeStorage Destructed;
6988 if (SecondTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) {
6989 ParsedType T = getTypeName(*SecondTypeName.Identifier,
6990 SecondTypeName.StartLocation,
6991 S, &SS, true, false, ObjectTypePtrForLookup,
6992 /*IsCtorOrDtorName*/true);
6994 ((SS.isSet() && !computeDeclContext(SS, false)) ||
6995 (!SS.isSet() && ObjectType->isDependentType()))) {
6996 // The name of the type being destroyed is a dependent name, and we
6997 // couldn't find anything useful in scope. Just store the identifier and
6998 // it's location, and we'll perform (qualified) name lookup again at
6999 // template instantiation time.
7000 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier,
7001 SecondTypeName.StartLocation);
7003 Diag(SecondTypeName.StartLocation,
7004 diag::err_pseudo_dtor_destructor_non_type)
7005 << SecondTypeName.Identifier << ObjectType;
7006 if (isSFINAEContext())
7009 // Recover by assuming we had the right type all along.
7010 DestructedType = ObjectType;
7012 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo);
7014 // Resolve the template-id to a type.
7015 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId;
7016 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
7017 TemplateId->NumArgs);
7018 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
7019 TemplateId->TemplateKWLoc,
7020 TemplateId->Template,
7022 TemplateId->TemplateNameLoc,
7023 TemplateId->LAngleLoc,
7025 TemplateId->RAngleLoc,
7026 /*IsCtorOrDtorName*/true);
7027 if (T.isInvalid() || !T.get()) {
7028 // Recover by assuming we had the right type all along.
7029 DestructedType = ObjectType;
7031 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo);
7034 // If we've performed some kind of recovery, (re-)build the type source
7036 if (!DestructedType.isNull()) {
7037 if (!DestructedTypeInfo)
7038 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType,
7039 SecondTypeName.StartLocation);
7040 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
7043 // Convert the name of the scope type (the type prior to '::') into a type.
7044 TypeSourceInfo *ScopeTypeInfo = nullptr;
7046 if (FirstTypeName.getKind() == UnqualifiedIdKind::IK_TemplateId ||
7047 FirstTypeName.Identifier) {
7048 if (FirstTypeName.getKind() == UnqualifiedIdKind::IK_Identifier) {
7049 ParsedType T = getTypeName(*FirstTypeName.Identifier,
7050 FirstTypeName.StartLocation,
7051 S, &SS, true, false, ObjectTypePtrForLookup,
7052 /*IsCtorOrDtorName*/true);
7054 Diag(FirstTypeName.StartLocation,
7055 diag::err_pseudo_dtor_destructor_non_type)
7056 << FirstTypeName.Identifier << ObjectType;
7058 if (isSFINAEContext())
7061 // Just drop this type. It's unnecessary anyway.
7062 ScopeType = QualType();
7064 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo);
7066 // Resolve the template-id to a type.
7067 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId;
7068 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
7069 TemplateId->NumArgs);
7070 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
7071 TemplateId->TemplateKWLoc,
7072 TemplateId->Template,
7074 TemplateId->TemplateNameLoc,
7075 TemplateId->LAngleLoc,
7077 TemplateId->RAngleLoc,
7078 /*IsCtorOrDtorName*/true);
7079 if (T.isInvalid() || !T.get()) {
7080 // Recover by dropping this type.
7081 ScopeType = QualType();
7083 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo);
7087 if (!ScopeType.isNull() && !ScopeTypeInfo)
7088 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType,
7089 FirstTypeName.StartLocation);
7092 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS,
7093 ScopeTypeInfo, CCLoc, TildeLoc,
7097 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
7098 SourceLocation OpLoc,
7099 tok::TokenKind OpKind,
7100 SourceLocation TildeLoc,
7101 const DeclSpec& DS) {
7102 QualType ObjectType;
7103 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
7106 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc(),
7110 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T);
7111 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc());
7112 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T);
7113 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo);
7115 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(),
7116 nullptr, SourceLocation(), TildeLoc,
7120 ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl,
7121 CXXConversionDecl *Method,
7122 bool HadMultipleCandidates) {
7123 // Convert the expression to match the conversion function's implicit object
7125 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/nullptr,
7127 if (Exp.isInvalid())
7130 if (Method->getParent()->isLambda() &&
7131 Method->getConversionType()->isBlockPointerType()) {
7132 // This is a lambda coversion to block pointer; check if the argument
7133 // was a LambdaExpr.
7135 CastExpr *CE = dyn_cast<CastExpr>(SubE);
7136 if (CE && CE->getCastKind() == CK_NoOp)
7137 SubE = CE->getSubExpr();
7138 SubE = SubE->IgnoreParens();
7139 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE))
7140 SubE = BE->getSubExpr();
7141 if (isa<LambdaExpr>(SubE)) {
7142 // For the conversion to block pointer on a lambda expression, we
7143 // construct a special BlockLiteral instead; this doesn't really make
7144 // a difference in ARC, but outside of ARC the resulting block literal
7145 // follows the normal lifetime rules for block literals instead of being
7147 DiagnosticErrorTrap Trap(Diags);
7148 PushExpressionEvaluationContext(
7149 ExpressionEvaluationContext::PotentiallyEvaluated);
7150 ExprResult BlockExp = BuildBlockForLambdaConversion(
7151 Exp.get()->getExprLoc(), Exp.get()->getExprLoc(), Method, Exp.get());
7152 PopExpressionEvaluationContext();
7154 if (BlockExp.isInvalid())
7155 Diag(Exp.get()->getExprLoc(), diag::note_lambda_to_block_conv);
7160 MemberExpr *ME = new (Context) MemberExpr(
7161 Exp.get(), /*IsArrow=*/false, SourceLocation(), Method, SourceLocation(),
7162 Context.BoundMemberTy, VK_RValue, OK_Ordinary);
7163 if (HadMultipleCandidates)
7164 ME->setHadMultipleCandidates(true);
7165 MarkMemberReferenced(ME);
7167 QualType ResultType = Method->getReturnType();
7168 ExprValueKind VK = Expr::getValueKindForType(ResultType);
7169 ResultType = ResultType.getNonLValueExprType(Context);
7171 CXXMemberCallExpr *CE =
7172 new (Context) CXXMemberCallExpr(Context, ME, None, ResultType, VK,
7173 Exp.get()->getLocEnd());
7175 if (CheckFunctionCall(Method, CE,
7176 Method->getType()->castAs<FunctionProtoType>()))
7182 ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand,
7183 SourceLocation RParen) {
7184 // If the operand is an unresolved lookup expression, the expression is ill-
7185 // formed per [over.over]p1, because overloaded function names cannot be used
7186 // without arguments except in explicit contexts.
7187 ExprResult R = CheckPlaceholderExpr(Operand);
7191 // The operand may have been modified when checking the placeholder type.
7194 if (!inTemplateInstantiation() && Operand->HasSideEffects(Context, false)) {
7195 // The expression operand for noexcept is in an unevaluated expression
7196 // context, so side effects could result in unintended consequences.
7197 Diag(Operand->getExprLoc(), diag::warn_side_effects_unevaluated_context);
7200 CanThrowResult CanThrow = canThrow(Operand);
7201 return new (Context)
7202 CXXNoexceptExpr(Context.BoolTy, Operand, CanThrow, KeyLoc, RParen);
7205 ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation,
7206 Expr *Operand, SourceLocation RParen) {
7207 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen);
7210 static bool IsSpecialDiscardedValue(Expr *E) {
7211 // In C++11, discarded-value expressions of a certain form are special,
7212 // according to [expr]p10:
7213 // The lvalue-to-rvalue conversion (4.1) is applied only if the
7214 // expression is an lvalue of volatile-qualified type and it has
7215 // one of the following forms:
7216 E = E->IgnoreParens();
7218 // - id-expression (5.1.1),
7219 if (isa<DeclRefExpr>(E))
7222 // - subscripting (5.2.1),
7223 if (isa<ArraySubscriptExpr>(E))
7226 // - class member access (5.2.5),
7227 if (isa<MemberExpr>(E))
7230 // - indirection (5.3.1),
7231 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E))
7232 if (UO->getOpcode() == UO_Deref)
7235 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
7236 // - pointer-to-member operation (5.5),
7237 if (BO->isPtrMemOp())
7240 // - comma expression (5.18) where the right operand is one of the above.
7241 if (BO->getOpcode() == BO_Comma)
7242 return IsSpecialDiscardedValue(BO->getRHS());
7245 // - conditional expression (5.16) where both the second and the third
7246 // operands are one of the above, or
7247 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E))
7248 return IsSpecialDiscardedValue(CO->getTrueExpr()) &&
7249 IsSpecialDiscardedValue(CO->getFalseExpr());
7250 // The related edge case of "*x ?: *x".
7251 if (BinaryConditionalOperator *BCO =
7252 dyn_cast<BinaryConditionalOperator>(E)) {
7253 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(BCO->getTrueExpr()))
7254 return IsSpecialDiscardedValue(OVE->getSourceExpr()) &&
7255 IsSpecialDiscardedValue(BCO->getFalseExpr());
7258 // Objective-C++ extensions to the rule.
7259 if (isa<PseudoObjectExpr>(E) || isa<ObjCIvarRefExpr>(E))
7265 /// Perform the conversions required for an expression used in a
7266 /// context that ignores the result.
7267 ExprResult Sema::IgnoredValueConversions(Expr *E) {
7268 if (E->hasPlaceholderType()) {
7269 ExprResult result = CheckPlaceholderExpr(E);
7270 if (result.isInvalid()) return E;
7275 // [Except in specific positions,] an lvalue that does not have
7276 // array type is converted to the value stored in the
7277 // designated object (and is no longer an lvalue).
7278 if (E->isRValue()) {
7279 // In C, function designators (i.e. expressions of function type)
7280 // are r-values, but we still want to do function-to-pointer decay
7281 // on them. This is both technically correct and convenient for
7283 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType())
7284 return DefaultFunctionArrayConversion(E);
7289 if (getLangOpts().CPlusPlus) {
7290 // The C++11 standard defines the notion of a discarded-value expression;
7291 // normally, we don't need to do anything to handle it, but if it is a
7292 // volatile lvalue with a special form, we perform an lvalue-to-rvalue
7294 if (getLangOpts().CPlusPlus11 && E->isGLValue() &&
7295 E->getType().isVolatileQualified() &&
7296 IsSpecialDiscardedValue(E)) {
7297 ExprResult Res = DefaultLvalueConversion(E);
7298 if (Res.isInvalid())
7304 // If the expression is a prvalue after this optional conversion, the
7305 // temporary materialization conversion is applied.
7307 // We skip this step: IR generation is able to synthesize the storage for
7308 // itself in the aggregate case, and adding the extra node to the AST is
7310 // FIXME: We don't emit lifetime markers for the temporaries due to this.
7311 // FIXME: Do any other AST consumers care about this?
7315 // GCC seems to also exclude expressions of incomplete enum type.
7316 if (const EnumType *T = E->getType()->getAs<EnumType>()) {
7317 if (!T->getDecl()->isComplete()) {
7318 // FIXME: stupid workaround for a codegen bug!
7319 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).get();
7324 ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
7325 if (Res.isInvalid())
7329 if (!E->getType()->isVoidType())
7330 RequireCompleteType(E->getExprLoc(), E->getType(),
7331 diag::err_incomplete_type);
7335 // If we can unambiguously determine whether Var can never be used
7336 // in a constant expression, return true.
7337 // - if the variable and its initializer are non-dependent, then
7338 // we can unambiguously check if the variable is a constant expression.
7339 // - if the initializer is not value dependent - we can determine whether
7340 // it can be used to initialize a constant expression. If Init can not
7341 // be used to initialize a constant expression we conclude that Var can
7342 // never be a constant expression.
7343 // - FXIME: if the initializer is dependent, we can still do some analysis and
7344 // identify certain cases unambiguously as non-const by using a Visitor:
7345 // - such as those that involve odr-use of a ParmVarDecl, involve a new
7346 // delete, lambda-expr, dynamic-cast, reinterpret-cast etc...
7347 static inline bool VariableCanNeverBeAConstantExpression(VarDecl *Var,
7348 ASTContext &Context) {
7349 if (isa<ParmVarDecl>(Var)) return true;
7350 const VarDecl *DefVD = nullptr;
7352 // If there is no initializer - this can not be a constant expression.
7353 if (!Var->getAnyInitializer(DefVD)) return true;
7355 if (DefVD->isWeak()) return false;
7356 EvaluatedStmt *Eval = DefVD->ensureEvaluatedStmt();
7358 Expr *Init = cast<Expr>(Eval->Value);
7360 if (Var->getType()->isDependentType() || Init->isValueDependent()) {
7361 // FIXME: Teach the constant evaluator to deal with the non-dependent parts
7362 // of value-dependent expressions, and use it here to determine whether the
7363 // initializer is a potential constant expression.
7367 return !IsVariableAConstantExpression(Var, Context);
7370 /// Check if the current lambda has any potential captures
7371 /// that must be captured by any of its enclosing lambdas that are ready to
7372 /// capture. If there is a lambda that can capture a nested
7373 /// potential-capture, go ahead and do so. Also, check to see if any
7374 /// variables are uncaptureable or do not involve an odr-use so do not
7375 /// need to be captured.
7377 static void CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(
7378 Expr *const FE, LambdaScopeInfo *const CurrentLSI, Sema &S) {
7380 assert(!S.isUnevaluatedContext());
7381 assert(S.CurContext->isDependentContext());
7383 DeclContext *DC = S.CurContext;
7384 while (DC && isa<CapturedDecl>(DC))
7385 DC = DC->getParent();
7387 CurrentLSI->CallOperator == DC &&
7388 "The current call operator must be synchronized with Sema's CurContext");
7391 const bool IsFullExprInstantiationDependent = FE->isInstantiationDependent();
7393 // All the potentially captureable variables in the current nested
7394 // lambda (within a generic outer lambda), must be captured by an
7395 // outer lambda that is enclosed within a non-dependent context.
7396 const unsigned NumPotentialCaptures =
7397 CurrentLSI->getNumPotentialVariableCaptures();
7398 for (unsigned I = 0; I != NumPotentialCaptures; ++I) {
7399 Expr *VarExpr = nullptr;
7400 VarDecl *Var = nullptr;
7401 CurrentLSI->getPotentialVariableCapture(I, Var, VarExpr);
7402 // If the variable is clearly identified as non-odr-used and the full
7403 // expression is not instantiation dependent, only then do we not
7404 // need to check enclosing lambda's for speculative captures.
7406 // Even though 'x' is not odr-used, it should be captured.
7408 // const int x = 10;
7409 // auto L = [=](auto a) {
7413 if (CurrentLSI->isVariableExprMarkedAsNonODRUsed(VarExpr) &&
7414 !IsFullExprInstantiationDependent)
7417 // If we have a capture-capable lambda for the variable, go ahead and
7418 // capture the variable in that lambda (and all its enclosing lambdas).
7419 if (const Optional<unsigned> Index =
7420 getStackIndexOfNearestEnclosingCaptureCapableLambda(
7421 S.FunctionScopes, Var, S)) {
7422 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
7423 MarkVarDeclODRUsed(Var, VarExpr->getExprLoc(), S,
7424 &FunctionScopeIndexOfCapturableLambda);
7426 const bool IsVarNeverAConstantExpression =
7427 VariableCanNeverBeAConstantExpression(Var, S.Context);
7428 if (!IsFullExprInstantiationDependent || IsVarNeverAConstantExpression) {
7429 // This full expression is not instantiation dependent or the variable
7430 // can not be used in a constant expression - which means
7431 // this variable must be odr-used here, so diagnose a
7432 // capture violation early, if the variable is un-captureable.
7433 // This is purely for diagnosing errors early. Otherwise, this
7434 // error would get diagnosed when the lambda becomes capture ready.
7435 QualType CaptureType, DeclRefType;
7436 SourceLocation ExprLoc = VarExpr->getExprLoc();
7437 if (S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
7438 /*EllipsisLoc*/ SourceLocation(),
7439 /*BuildAndDiagnose*/false, CaptureType,
7440 DeclRefType, nullptr)) {
7441 // We will never be able to capture this variable, and we need
7442 // to be able to in any and all instantiations, so diagnose it.
7443 S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
7444 /*EllipsisLoc*/ SourceLocation(),
7445 /*BuildAndDiagnose*/true, CaptureType,
7446 DeclRefType, nullptr);
7451 // Check if 'this' needs to be captured.
7452 if (CurrentLSI->hasPotentialThisCapture()) {
7453 // If we have a capture-capable lambda for 'this', go ahead and capture
7454 // 'this' in that lambda (and all its enclosing lambdas).
7455 if (const Optional<unsigned> Index =
7456 getStackIndexOfNearestEnclosingCaptureCapableLambda(
7457 S.FunctionScopes, /*0 is 'this'*/ nullptr, S)) {
7458 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
7459 S.CheckCXXThisCapture(CurrentLSI->PotentialThisCaptureLocation,
7460 /*Explicit*/ false, /*BuildAndDiagnose*/ true,
7461 &FunctionScopeIndexOfCapturableLambda);
7465 // Reset all the potential captures at the end of each full-expression.
7466 CurrentLSI->clearPotentialCaptures();
7469 static ExprResult attemptRecovery(Sema &SemaRef,
7470 const TypoCorrectionConsumer &Consumer,
7471 const TypoCorrection &TC) {
7472 LookupResult R(SemaRef, Consumer.getLookupResult().getLookupNameInfo(),
7473 Consumer.getLookupResult().getLookupKind());
7474 const CXXScopeSpec *SS = Consumer.getSS();
7477 // Use an approprate CXXScopeSpec for building the expr.
7478 if (auto *NNS = TC.getCorrectionSpecifier())
7479 NewSS.MakeTrivial(SemaRef.Context, NNS, TC.getCorrectionRange());
7480 else if (SS && !TC.WillReplaceSpecifier())
7483 if (auto *ND = TC.getFoundDecl()) {
7484 R.setLookupName(ND->getDeclName());
7486 if (ND->isCXXClassMember()) {
7487 // Figure out the correct naming class to add to the LookupResult.
7488 CXXRecordDecl *Record = nullptr;
7489 if (auto *NNS = TC.getCorrectionSpecifier())
7490 Record = NNS->getAsType()->getAsCXXRecordDecl();
7493 dyn_cast<CXXRecordDecl>(ND->getDeclContext()->getRedeclContext());
7495 R.setNamingClass(Record);
7497 // Detect and handle the case where the decl might be an implicit
7499 bool MightBeImplicitMember;
7500 if (!Consumer.isAddressOfOperand())
7501 MightBeImplicitMember = true;
7502 else if (!NewSS.isEmpty())
7503 MightBeImplicitMember = false;
7504 else if (R.isOverloadedResult())
7505 MightBeImplicitMember = false;
7506 else if (R.isUnresolvableResult())
7507 MightBeImplicitMember = true;
7509 MightBeImplicitMember = isa<FieldDecl>(ND) ||
7510 isa<IndirectFieldDecl>(ND) ||
7511 isa<MSPropertyDecl>(ND);
7513 if (MightBeImplicitMember)
7514 return SemaRef.BuildPossibleImplicitMemberExpr(
7515 NewSS, /*TemplateKWLoc*/ SourceLocation(), R,
7516 /*TemplateArgs*/ nullptr, /*S*/ nullptr);
7517 } else if (auto *Ivar = dyn_cast<ObjCIvarDecl>(ND)) {
7518 return SemaRef.LookupInObjCMethod(R, Consumer.getScope(),
7519 Ivar->getIdentifier());
7523 return SemaRef.BuildDeclarationNameExpr(NewSS, R, /*NeedsADL*/ false,
7524 /*AcceptInvalidDecl*/ true);
7528 class FindTypoExprs : public RecursiveASTVisitor<FindTypoExprs> {
7529 llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs;
7532 explicit FindTypoExprs(llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs)
7533 : TypoExprs(TypoExprs) {}
7534 bool VisitTypoExpr(TypoExpr *TE) {
7535 TypoExprs.insert(TE);
7540 class TransformTypos : public TreeTransform<TransformTypos> {
7541 typedef TreeTransform<TransformTypos> BaseTransform;
7543 VarDecl *InitDecl; // A decl to avoid as a correction because it is in the
7544 // process of being initialized.
7545 llvm::function_ref<ExprResult(Expr *)> ExprFilter;
7546 llvm::SmallSetVector<TypoExpr *, 2> TypoExprs, AmbiguousTypoExprs;
7547 llvm::SmallDenseMap<TypoExpr *, ExprResult, 2> TransformCache;
7548 llvm::SmallDenseMap<OverloadExpr *, Expr *, 4> OverloadResolution;
7550 /// Emit diagnostics for all of the TypoExprs encountered.
7551 /// If the TypoExprs were successfully corrected, then the diagnostics should
7552 /// suggest the corrections. Otherwise the diagnostics will not suggest
7553 /// anything (having been passed an empty TypoCorrection).
7554 void EmitAllDiagnostics() {
7555 for (TypoExpr *TE : TypoExprs) {
7556 auto &State = SemaRef.getTypoExprState(TE);
7557 if (State.DiagHandler) {
7558 TypoCorrection TC = State.Consumer->getCurrentCorrection();
7559 ExprResult Replacement = TransformCache[TE];
7561 // Extract the NamedDecl from the transformed TypoExpr and add it to the
7562 // TypoCorrection, replacing the existing decls. This ensures the right
7563 // NamedDecl is used in diagnostics e.g. in the case where overload
7564 // resolution was used to select one from several possible decls that
7565 // had been stored in the TypoCorrection.
7566 if (auto *ND = getDeclFromExpr(
7567 Replacement.isInvalid() ? nullptr : Replacement.get()))
7568 TC.setCorrectionDecl(ND);
7570 State.DiagHandler(TC);
7572 SemaRef.clearDelayedTypo(TE);
7576 /// If corrections for the first TypoExpr have been exhausted for a
7577 /// given combination of the other TypoExprs, retry those corrections against
7578 /// the next combination of substitutions for the other TypoExprs by advancing
7579 /// to the next potential correction of the second TypoExpr. For the second
7580 /// and subsequent TypoExprs, if its stream of corrections has been exhausted,
7581 /// the stream is reset and the next TypoExpr's stream is advanced by one (a
7582 /// TypoExpr's correction stream is advanced by removing the TypoExpr from the
7583 /// TransformCache). Returns true if there is still any untried combinations
7585 bool CheckAndAdvanceTypoExprCorrectionStreams() {
7586 for (auto TE : TypoExprs) {
7587 auto &State = SemaRef.getTypoExprState(TE);
7588 TransformCache.erase(TE);
7589 if (!State.Consumer->finished())
7591 State.Consumer->resetCorrectionStream();
7596 NamedDecl *getDeclFromExpr(Expr *E) {
7597 if (auto *OE = dyn_cast_or_null<OverloadExpr>(E))
7598 E = OverloadResolution[OE];
7602 if (auto *DRE = dyn_cast<DeclRefExpr>(E))
7603 return DRE->getFoundDecl();
7604 if (auto *ME = dyn_cast<MemberExpr>(E))
7605 return ME->getFoundDecl();
7606 // FIXME: Add any other expr types that could be be seen by the delayed typo
7607 // correction TreeTransform for which the corresponding TypoCorrection could
7608 // contain multiple decls.
7612 ExprResult TryTransform(Expr *E) {
7613 Sema::SFINAETrap Trap(SemaRef);
7614 ExprResult Res = TransformExpr(E);
7615 if (Trap.hasErrorOccurred() || Res.isInvalid())
7618 return ExprFilter(Res.get());
7622 TransformTypos(Sema &SemaRef, VarDecl *InitDecl, llvm::function_ref<ExprResult(Expr *)> Filter)
7623 : BaseTransform(SemaRef), InitDecl(InitDecl), ExprFilter(Filter) {}
7625 ExprResult RebuildCallExpr(Expr *Callee, SourceLocation LParenLoc,
7627 SourceLocation RParenLoc,
7628 Expr *ExecConfig = nullptr) {
7629 auto Result = BaseTransform::RebuildCallExpr(Callee, LParenLoc, Args,
7630 RParenLoc, ExecConfig);
7631 if (auto *OE = dyn_cast<OverloadExpr>(Callee)) {
7632 if (Result.isUsable()) {
7633 Expr *ResultCall = Result.get();
7634 if (auto *BE = dyn_cast<CXXBindTemporaryExpr>(ResultCall))
7635 ResultCall = BE->getSubExpr();
7636 if (auto *CE = dyn_cast<CallExpr>(ResultCall))
7637 OverloadResolution[OE] = CE->getCallee();
7643 ExprResult TransformLambdaExpr(LambdaExpr *E) { return Owned(E); }
7645 ExprResult TransformBlockExpr(BlockExpr *E) { return Owned(E); }
7647 ExprResult Transform(Expr *E) {
7650 Res = TryTransform(E);
7652 // Exit if either the transform was valid or if there were no TypoExprs
7653 // to transform that still have any untried correction candidates..
7654 if (!Res.isInvalid() ||
7655 !CheckAndAdvanceTypoExprCorrectionStreams())
7659 // Ensure none of the TypoExprs have multiple typo correction candidates
7660 // with the same edit length that pass all the checks and filters.
7661 // TODO: Properly handle various permutations of possible corrections when
7662 // there is more than one potentially ambiguous typo correction.
7663 // Also, disable typo correction while attempting the transform when
7664 // handling potentially ambiguous typo corrections as any new TypoExprs will
7665 // have been introduced by the application of one of the correction
7666 // candidates and add little to no value if corrected.
7667 SemaRef.DisableTypoCorrection = true;
7668 while (!AmbiguousTypoExprs.empty()) {
7669 auto TE = AmbiguousTypoExprs.back();
7670 auto Cached = TransformCache[TE];
7671 auto &State = SemaRef.getTypoExprState(TE);
7672 State.Consumer->saveCurrentPosition();
7673 TransformCache.erase(TE);
7674 if (!TryTransform(E).isInvalid()) {
7675 State.Consumer->resetCorrectionStream();
7676 TransformCache.erase(TE);
7680 AmbiguousTypoExprs.remove(TE);
7681 State.Consumer->restoreSavedPosition();
7682 TransformCache[TE] = Cached;
7684 SemaRef.DisableTypoCorrection = false;
7686 // Ensure that all of the TypoExprs within the current Expr have been found.
7687 if (!Res.isUsable())
7688 FindTypoExprs(TypoExprs).TraverseStmt(E);
7690 EmitAllDiagnostics();
7695 ExprResult TransformTypoExpr(TypoExpr *E) {
7696 // If the TypoExpr hasn't been seen before, record it. Otherwise, return the
7697 // cached transformation result if there is one and the TypoExpr isn't the
7698 // first one that was encountered.
7699 auto &CacheEntry = TransformCache[E];
7700 if (!TypoExprs.insert(E) && !CacheEntry.isUnset()) {
7704 auto &State = SemaRef.getTypoExprState(E);
7705 assert(State.Consumer && "Cannot transform a cleared TypoExpr");
7707 // For the first TypoExpr and an uncached TypoExpr, find the next likely
7708 // typo correction and return it.
7709 while (TypoCorrection TC = State.Consumer->getNextCorrection()) {
7710 if (InitDecl && TC.getFoundDecl() == InitDecl)
7712 // FIXME: If we would typo-correct to an invalid declaration, it's
7713 // probably best to just suppress all errors from this typo correction.
7714 ExprResult NE = State.RecoveryHandler ?
7715 State.RecoveryHandler(SemaRef, E, TC) :
7716 attemptRecovery(SemaRef, *State.Consumer, TC);
7717 if (!NE.isInvalid()) {
7718 // Check whether there may be a second viable correction with the same
7719 // edit distance; if so, remember this TypoExpr may have an ambiguous
7720 // correction so it can be more thoroughly vetted later.
7721 TypoCorrection Next;
7722 if ((Next = State.Consumer->peekNextCorrection()) &&
7723 Next.getEditDistance(false) == TC.getEditDistance(false)) {
7724 AmbiguousTypoExprs.insert(E);
7726 AmbiguousTypoExprs.remove(E);
7728 assert(!NE.isUnset() &&
7729 "Typo was transformed into a valid-but-null ExprResult");
7730 return CacheEntry = NE;
7733 return CacheEntry = ExprError();
7739 Sema::CorrectDelayedTyposInExpr(Expr *E, VarDecl *InitDecl,
7740 llvm::function_ref<ExprResult(Expr *)> Filter) {
7741 // If the current evaluation context indicates there are uncorrected typos
7742 // and the current expression isn't guaranteed to not have typos, try to
7743 // resolve any TypoExpr nodes that might be in the expression.
7744 if (E && !ExprEvalContexts.empty() && ExprEvalContexts.back().NumTypos &&
7745 (E->isTypeDependent() || E->isValueDependent() ||
7746 E->isInstantiationDependent())) {
7747 auto TyposResolved = DelayedTypos.size();
7748 auto Result = TransformTypos(*this, InitDecl, Filter).Transform(E);
7749 TyposResolved -= DelayedTypos.size();
7750 if (Result.isInvalid() || Result.get() != E) {
7751 ExprEvalContexts.back().NumTypos -= TyposResolved;
7754 assert(TyposResolved == 0 && "Corrected typo but got same Expr back?");
7759 ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC,
7760 bool DiscardedValue,
7762 bool IsLambdaInitCaptureInitializer) {
7763 ExprResult FullExpr = FE;
7765 if (!FullExpr.get())
7768 // If we are an init-expression in a lambdas init-capture, we should not
7769 // diagnose an unexpanded pack now (will be diagnosed once lambda-expr
7770 // containing full-expression is done).
7771 // template<class ... Ts> void test(Ts ... t) {
7772 // test([&a(t)]() { <-- (t) is an init-expr that shouldn't be diagnosed now.
7776 // FIXME: This is a hack. It would be better if we pushed the lambda scope
7777 // when we parse the lambda introducer, and teach capturing (but not
7778 // unexpanded pack detection) to walk over LambdaScopeInfos which don't have a
7779 // corresponding class yet (that is, have LambdaScopeInfo either represent a
7780 // lambda where we've entered the introducer but not the body, or represent a
7781 // lambda where we've entered the body, depending on where the
7782 // parser/instantiation has got to).
7783 if (!IsLambdaInitCaptureInitializer &&
7784 DiagnoseUnexpandedParameterPack(FullExpr.get()))
7787 // Top-level expressions default to 'id' when we're in a debugger.
7788 if (DiscardedValue && getLangOpts().DebuggerCastResultToId &&
7789 FullExpr.get()->getType() == Context.UnknownAnyTy) {
7790 FullExpr = forceUnknownAnyToType(FullExpr.get(), Context.getObjCIdType());
7791 if (FullExpr.isInvalid())
7795 if (DiscardedValue) {
7796 FullExpr = CheckPlaceholderExpr(FullExpr.get());
7797 if (FullExpr.isInvalid())
7800 FullExpr = IgnoredValueConversions(FullExpr.get());
7801 if (FullExpr.isInvalid())
7805 FullExpr = CorrectDelayedTyposInExpr(FullExpr.get());
7806 if (FullExpr.isInvalid())
7809 CheckCompletedExpr(FullExpr.get(), CC, IsConstexpr);
7811 // At the end of this full expression (which could be a deeply nested
7812 // lambda), if there is a potential capture within the nested lambda,
7813 // have the outer capture-able lambda try and capture it.
7814 // Consider the following code:
7815 // void f(int, int);
7816 // void f(const int&, double);
7818 // const int x = 10, y = 20;
7819 // auto L = [=](auto a) {
7820 // auto M = [=](auto b) {
7821 // f(x, b); <-- requires x to be captured by L and M
7822 // f(y, a); <-- requires y to be captured by L, but not all Ms
7827 // FIXME: Also consider what happens for something like this that involves
7828 // the gnu-extension statement-expressions or even lambda-init-captures:
7831 // auto L = [&](auto a) {
7832 // +n + ({ 0; a; });
7836 // Here, we see +n, and then the full-expression 0; ends, so we don't
7837 // capture n (and instead remove it from our list of potential captures),
7838 // and then the full-expression +n + ({ 0; }); ends, but it's too late
7839 // for us to see that we need to capture n after all.
7841 LambdaScopeInfo *const CurrentLSI =
7842 getCurLambda(/*IgnoreCapturedRegions=*/true);
7843 // FIXME: PR 17877 showed that getCurLambda() can return a valid pointer
7844 // even if CurContext is not a lambda call operator. Refer to that Bug Report
7845 // for an example of the code that might cause this asynchrony.
7846 // By ensuring we are in the context of a lambda's call operator
7847 // we can fix the bug (we only need to check whether we need to capture
7848 // if we are within a lambda's body); but per the comments in that
7849 // PR, a proper fix would entail :
7850 // "Alternative suggestion:
7851 // - Add to Sema an integer holding the smallest (outermost) scope
7852 // index that we are *lexically* within, and save/restore/set to
7853 // FunctionScopes.size() in InstantiatingTemplate's
7854 // constructor/destructor.
7855 // - Teach the handful of places that iterate over FunctionScopes to
7856 // stop at the outermost enclosing lexical scope."
7857 DeclContext *DC = CurContext;
7858 while (DC && isa<CapturedDecl>(DC))
7859 DC = DC->getParent();
7860 const bool IsInLambdaDeclContext = isLambdaCallOperator(DC);
7861 if (IsInLambdaDeclContext && CurrentLSI &&
7862 CurrentLSI->hasPotentialCaptures() && !FullExpr.isInvalid())
7863 CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(FE, CurrentLSI,
7865 return MaybeCreateExprWithCleanups(FullExpr);
7868 StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) {
7869 if (!FullStmt) return StmtError();
7871 return MaybeCreateStmtWithCleanups(FullStmt);
7874 Sema::IfExistsResult
7875 Sema::CheckMicrosoftIfExistsSymbol(Scope *S,
7877 const DeclarationNameInfo &TargetNameInfo) {
7878 DeclarationName TargetName = TargetNameInfo.getName();
7880 return IER_DoesNotExist;
7882 // If the name itself is dependent, then the result is dependent.
7883 if (TargetName.isDependentName())
7884 return IER_Dependent;
7886 // Do the redeclaration lookup in the current scope.
7887 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName,
7888 Sema::NotForRedeclaration);
7889 LookupParsedName(R, S, &SS);
7890 R.suppressDiagnostics();
7892 switch (R.getResultKind()) {
7893 case LookupResult::Found:
7894 case LookupResult::FoundOverloaded:
7895 case LookupResult::FoundUnresolvedValue:
7896 case LookupResult::Ambiguous:
7899 case LookupResult::NotFound:
7900 return IER_DoesNotExist;
7902 case LookupResult::NotFoundInCurrentInstantiation:
7903 return IER_Dependent;
7906 llvm_unreachable("Invalid LookupResult Kind!");
7909 Sema::IfExistsResult
7910 Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc,
7911 bool IsIfExists, CXXScopeSpec &SS,
7912 UnqualifiedId &Name) {
7913 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
7915 // Check for an unexpanded parameter pack.
7916 auto UPPC = IsIfExists ? UPPC_IfExists : UPPC_IfNotExists;
7917 if (DiagnoseUnexpandedParameterPack(SS, UPPC) ||
7918 DiagnoseUnexpandedParameterPack(TargetNameInfo, UPPC))
7921 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo);