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 /// \brief 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/PartialDiagnostic.h"
28 #include "clang/Basic/TargetInfo.h"
29 #include "clang/Lex/Preprocessor.h"
30 #include "clang/Sema/DeclSpec.h"
31 #include "clang/Sema/Initialization.h"
32 #include "clang/Sema/Lookup.h"
33 #include "clang/Sema/ParsedTemplate.h"
34 #include "clang/Sema/Scope.h"
35 #include "clang/Sema/ScopeInfo.h"
36 #include "clang/Sema/SemaLambda.h"
37 #include "clang/Sema/TemplateDeduction.h"
38 #include "llvm/ADT/APInt.h"
39 #include "llvm/ADT/STLExtras.h"
40 #include "llvm/Support/ErrorHandling.h"
41 using namespace clang;
44 /// \brief Handle the result of the special case name lookup for inheriting
45 /// constructor declarations. 'NS::X::X' and 'NS::X<...>::X' are treated as
46 /// constructor names in member using declarations, even if 'X' is not the
47 /// name of the corresponding type.
48 ParsedType Sema::getInheritingConstructorName(CXXScopeSpec &SS,
49 SourceLocation NameLoc,
50 IdentifierInfo &Name) {
51 NestedNameSpecifier *NNS = SS.getScopeRep();
53 // Convert the nested-name-specifier into a type.
55 switch (NNS->getKind()) {
56 case NestedNameSpecifier::TypeSpec:
57 case NestedNameSpecifier::TypeSpecWithTemplate:
58 Type = QualType(NNS->getAsType(), 0);
61 case NestedNameSpecifier::Identifier:
62 // Strip off the last layer of the nested-name-specifier and build a
63 // typename type for it.
64 assert(NNS->getAsIdentifier() == &Name && "not a constructor name");
65 Type = Context.getDependentNameType(ETK_None, NNS->getPrefix(),
66 NNS->getAsIdentifier());
69 case NestedNameSpecifier::Global:
70 case NestedNameSpecifier::Super:
71 case NestedNameSpecifier::Namespace:
72 case NestedNameSpecifier::NamespaceAlias:
73 llvm_unreachable("Nested name specifier is not a type for inheriting ctor");
76 // This reference to the type is located entirely at the location of the
77 // final identifier in the qualified-id.
78 return CreateParsedType(Type,
79 Context.getTrivialTypeSourceInfo(Type, NameLoc));
82 ParsedType Sema::getDestructorName(SourceLocation TildeLoc,
84 SourceLocation NameLoc,
85 Scope *S, CXXScopeSpec &SS,
86 ParsedType ObjectTypePtr,
87 bool EnteringContext) {
88 // Determine where to perform name lookup.
90 // FIXME: This area of the standard is very messy, and the current
91 // wording is rather unclear about which scopes we search for the
92 // destructor name; see core issues 399 and 555. Issue 399 in
93 // particular shows where the current description of destructor name
94 // lookup is completely out of line with existing practice, e.g.,
95 // this appears to be ill-formed:
98 // template <typename T> struct S {
103 // void f(N::S<int>* s) {
104 // s->N::S<int>::~S();
107 // See also PR6358 and PR6359.
108 // For this reason, we're currently only doing the C++03 version of this
109 // code; the C++0x version has to wait until we get a proper spec.
111 DeclContext *LookupCtx = nullptr;
112 bool isDependent = false;
113 bool LookInScope = false;
118 // If we have an object type, it's because we are in a
119 // pseudo-destructor-expression or a member access expression, and
120 // we know what type we're looking for.
122 SearchType = GetTypeFromParser(ObjectTypePtr);
125 NestedNameSpecifier *NNS = SS.getScopeRep();
127 bool AlreadySearched = false;
128 bool LookAtPrefix = true;
129 // C++11 [basic.lookup.qual]p6:
130 // If a pseudo-destructor-name (5.2.4) contains a nested-name-specifier,
131 // the type-names are looked up as types in the scope designated by the
132 // nested-name-specifier. Similarly, in a qualified-id of the form:
134 // nested-name-specifier[opt] class-name :: ~ class-name
136 // the second class-name is looked up in the same scope as the first.
138 // Here, we determine whether the code below is permitted to look at the
139 // prefix of the nested-name-specifier.
140 DeclContext *DC = computeDeclContext(SS, EnteringContext);
141 if (DC && DC->isFileContext()) {
142 AlreadySearched = true;
145 } else if (DC && isa<CXXRecordDecl>(DC)) {
146 LookAtPrefix = false;
150 // The second case from the C++03 rules quoted further above.
151 NestedNameSpecifier *Prefix = nullptr;
152 if (AlreadySearched) {
153 // Nothing left to do.
154 } else if (LookAtPrefix && (Prefix = NNS->getPrefix())) {
155 CXXScopeSpec PrefixSS;
156 PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data()));
157 LookupCtx = computeDeclContext(PrefixSS, EnteringContext);
158 isDependent = isDependentScopeSpecifier(PrefixSS);
159 } else if (ObjectTypePtr) {
160 LookupCtx = computeDeclContext(SearchType);
161 isDependent = SearchType->isDependentType();
163 LookupCtx = computeDeclContext(SS, EnteringContext);
164 isDependent = LookupCtx && LookupCtx->isDependentContext();
166 } else if (ObjectTypePtr) {
167 // C++ [basic.lookup.classref]p3:
168 // If the unqualified-id is ~type-name, the type-name is looked up
169 // in the context of the entire postfix-expression. If the type T
170 // of the object expression is of a class type C, the type-name is
171 // also looked up in the scope of class C. At least one of the
172 // lookups shall find a name that refers to (possibly
174 LookupCtx = computeDeclContext(SearchType);
175 isDependent = SearchType->isDependentType();
176 assert((isDependent || !SearchType->isIncompleteType()) &&
177 "Caller should have completed object type");
181 // Perform lookup into the current scope (only).
185 TypeDecl *NonMatchingTypeDecl = nullptr;
186 LookupResult Found(*this, &II, NameLoc, LookupOrdinaryName);
187 for (unsigned Step = 0; Step != 2; ++Step) {
188 // Look for the name first in the computed lookup context (if we
189 // have one) and, if that fails to find a match, in the scope (if
190 // we're allowed to look there).
192 if (Step == 0 && LookupCtx)
193 LookupQualifiedName(Found, LookupCtx);
194 else if (Step == 1 && LookInScope && S)
195 LookupName(Found, S);
199 // FIXME: Should we be suppressing ambiguities here?
200 if (Found.isAmbiguous())
203 if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) {
204 QualType T = Context.getTypeDeclType(Type);
205 MarkAnyDeclReferenced(Type->getLocation(), Type, /*OdrUse=*/false);
207 if (SearchType.isNull() || SearchType->isDependentType() ||
208 Context.hasSameUnqualifiedType(T, SearchType)) {
209 // We found our type!
211 return CreateParsedType(T,
212 Context.getTrivialTypeSourceInfo(T, NameLoc));
215 if (!SearchType.isNull())
216 NonMatchingTypeDecl = Type;
219 // If the name that we found is a class template name, and it is
220 // the same name as the template name in the last part of the
221 // nested-name-specifier (if present) or the object type, then
222 // this is the destructor for that class.
223 // FIXME: This is a workaround until we get real drafting for core
224 // issue 399, for which there isn't even an obvious direction.
225 if (ClassTemplateDecl *Template = Found.getAsSingle<ClassTemplateDecl>()) {
226 QualType MemberOfType;
228 if (DeclContext *Ctx = computeDeclContext(SS, EnteringContext)) {
229 // Figure out the type of the context, if it has one.
230 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx))
231 MemberOfType = Context.getTypeDeclType(Record);
234 if (MemberOfType.isNull())
235 MemberOfType = SearchType;
237 if (MemberOfType.isNull())
240 // We're referring into a class template specialization. If the
241 // class template we found is the same as the template being
242 // specialized, we found what we are looking for.
243 if (const RecordType *Record = MemberOfType->getAs<RecordType>()) {
244 if (ClassTemplateSpecializationDecl *Spec
245 = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) {
246 if (Spec->getSpecializedTemplate()->getCanonicalDecl() ==
247 Template->getCanonicalDecl())
248 return CreateParsedType(
250 Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
256 // We're referring to an unresolved class template
257 // specialization. Determine whether we class template we found
258 // is the same as the template being specialized or, if we don't
259 // know which template is being specialized, that it at least
260 // has the same name.
261 if (const TemplateSpecializationType *SpecType
262 = MemberOfType->getAs<TemplateSpecializationType>()) {
263 TemplateName SpecName = SpecType->getTemplateName();
265 // The class template we found is the same template being
267 if (TemplateDecl *SpecTemplate = SpecName.getAsTemplateDecl()) {
268 if (SpecTemplate->getCanonicalDecl() == Template->getCanonicalDecl())
269 return CreateParsedType(
271 Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
276 // The class template we found has the same name as the
277 // (dependent) template name being specialized.
278 if (DependentTemplateName *DepTemplate
279 = SpecName.getAsDependentTemplateName()) {
280 if (DepTemplate->isIdentifier() &&
281 DepTemplate->getIdentifier() == Template->getIdentifier())
282 return CreateParsedType(
284 Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
293 // We didn't find our type, but that's okay: it's dependent
296 // FIXME: What if we have no nested-name-specifier?
297 QualType T = CheckTypenameType(ETK_None, SourceLocation(),
298 SS.getWithLocInContext(Context),
300 return ParsedType::make(T);
303 if (NonMatchingTypeDecl) {
304 QualType T = Context.getTypeDeclType(NonMatchingTypeDecl);
305 Diag(NameLoc, diag::err_destructor_expr_type_mismatch)
307 Diag(NonMatchingTypeDecl->getLocation(), diag::note_destructor_type_here)
309 } else if (ObjectTypePtr)
310 Diag(NameLoc, diag::err_ident_in_dtor_not_a_type)
313 SemaDiagnosticBuilder DtorDiag = Diag(NameLoc,
314 diag::err_destructor_class_name);
316 const DeclContext *Ctx = S->getEntity();
317 if (const CXXRecordDecl *Class = dyn_cast_or_null<CXXRecordDecl>(Ctx))
318 DtorDiag << FixItHint::CreateReplacement(SourceRange(NameLoc),
319 Class->getNameAsString());
326 ParsedType Sema::getDestructorTypeForDecltype(const DeclSpec &DS,
327 ParsedType ObjectType) {
328 if (DS.getTypeSpecType() == DeclSpec::TST_error)
331 if (DS.getTypeSpecType() == DeclSpec::TST_decltype_auto) {
332 Diag(DS.getTypeSpecTypeLoc(), diag::err_decltype_auto_invalid);
336 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype &&
337 "unexpected type in getDestructorType");
338 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
340 // If we know the type of the object, check that the correct destructor
341 // type was named now; we can give better diagnostics this way.
342 QualType SearchType = GetTypeFromParser(ObjectType);
343 if (!SearchType.isNull() && !SearchType->isDependentType() &&
344 !Context.hasSameUnqualifiedType(T, SearchType)) {
345 Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch)
350 return ParsedType::make(T);
353 bool Sema::checkLiteralOperatorId(const CXXScopeSpec &SS,
354 const UnqualifiedId &Name) {
355 assert(Name.getKind() == UnqualifiedId::IK_LiteralOperatorId);
360 switch (SS.getScopeRep()->getKind()) {
361 case NestedNameSpecifier::Identifier:
362 case NestedNameSpecifier::TypeSpec:
363 case NestedNameSpecifier::TypeSpecWithTemplate:
364 // Per C++11 [over.literal]p2, literal operators can only be declared at
365 // namespace scope. Therefore, this unqualified-id cannot name anything.
366 // Reject it early, because we have no AST representation for this in the
367 // case where the scope is dependent.
368 Diag(Name.getLocStart(), diag::err_literal_operator_id_outside_namespace)
372 case NestedNameSpecifier::Global:
373 case NestedNameSpecifier::Super:
374 case NestedNameSpecifier::Namespace:
375 case NestedNameSpecifier::NamespaceAlias:
379 llvm_unreachable("unknown nested name specifier kind");
382 /// \brief Build a C++ typeid expression with a type operand.
383 ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
384 SourceLocation TypeidLoc,
385 TypeSourceInfo *Operand,
386 SourceLocation RParenLoc) {
387 // C++ [expr.typeid]p4:
388 // The top-level cv-qualifiers of the lvalue expression or the type-id
389 // that is the operand of typeid are always ignored.
390 // If the type of the type-id is a class type or a reference to a class
391 // type, the class shall be completely-defined.
394 = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(),
396 if (T->getAs<RecordType>() &&
397 RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
400 if (T->isVariablyModifiedType())
401 return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid) << T);
403 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), Operand,
404 SourceRange(TypeidLoc, RParenLoc));
407 /// \brief Build a C++ typeid expression with an expression operand.
408 ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
409 SourceLocation TypeidLoc,
411 SourceLocation RParenLoc) {
412 bool WasEvaluated = false;
413 if (E && !E->isTypeDependent()) {
414 if (E->getType()->isPlaceholderType()) {
415 ExprResult result = CheckPlaceholderExpr(E);
416 if (result.isInvalid()) return ExprError();
420 QualType T = E->getType();
421 if (const RecordType *RecordT = T->getAs<RecordType>()) {
422 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl());
423 // C++ [expr.typeid]p3:
424 // [...] If the type of the expression is a class type, the class
425 // shall be completely-defined.
426 if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
429 // C++ [expr.typeid]p3:
430 // When typeid is applied to an expression other than an glvalue of a
431 // polymorphic class type [...] [the] expression is an unevaluated
433 if (RecordD->isPolymorphic() && E->isGLValue()) {
434 // The subexpression is potentially evaluated; switch the context
435 // and recheck the subexpression.
436 ExprResult Result = TransformToPotentiallyEvaluated(E);
437 if (Result.isInvalid()) return ExprError();
440 // We require a vtable to query the type at run time.
441 MarkVTableUsed(TypeidLoc, RecordD);
446 // C++ [expr.typeid]p4:
447 // [...] If the type of the type-id is a reference to a possibly
448 // cv-qualified type, the result of the typeid expression refers to a
449 // std::type_info object representing the cv-unqualified referenced
452 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals);
453 if (!Context.hasSameType(T, UnqualT)) {
455 E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).get();
459 if (E->getType()->isVariablyModifiedType())
460 return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid)
462 else if (!inTemplateInstantiation() &&
463 E->HasSideEffects(Context, WasEvaluated)) {
464 // The expression operand for typeid is in an unevaluated expression
465 // context, so side effects could result in unintended consequences.
466 Diag(E->getExprLoc(), WasEvaluated
467 ? diag::warn_side_effects_typeid
468 : diag::warn_side_effects_unevaluated_context);
471 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), E,
472 SourceRange(TypeidLoc, RParenLoc));
475 /// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression);
477 Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc,
478 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
479 // Find the std::type_info type.
480 if (!getStdNamespace())
481 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
483 if (!CXXTypeInfoDecl) {
484 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info");
485 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName);
486 LookupQualifiedName(R, getStdNamespace());
487 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
488 // Microsoft's typeinfo doesn't have type_info in std but in the global
489 // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153.
490 if (!CXXTypeInfoDecl && LangOpts.MSVCCompat) {
491 LookupQualifiedName(R, Context.getTranslationUnitDecl());
492 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
494 if (!CXXTypeInfoDecl)
495 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
498 if (!getLangOpts().RTTI) {
499 return ExprError(Diag(OpLoc, diag::err_no_typeid_with_fno_rtti));
502 QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl);
505 // The operand is a type; handle it as such.
506 TypeSourceInfo *TInfo = nullptr;
507 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
513 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
515 return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc);
518 // The operand is an expression.
519 return BuildCXXTypeId(TypeInfoType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
522 /// Grabs __declspec(uuid()) off a type, or returns 0 if we cannot resolve to
525 getUuidAttrOfType(Sema &SemaRef, QualType QT,
526 llvm::SmallSetVector<const UuidAttr *, 1> &UuidAttrs) {
527 // Optionally remove one level of pointer, reference or array indirection.
528 const Type *Ty = QT.getTypePtr();
529 if (QT->isPointerType() || QT->isReferenceType())
530 Ty = QT->getPointeeType().getTypePtr();
531 else if (QT->isArrayType())
532 Ty = Ty->getBaseElementTypeUnsafe();
534 const auto *TD = Ty->getAsTagDecl();
538 if (const auto *Uuid = TD->getMostRecentDecl()->getAttr<UuidAttr>()) {
539 UuidAttrs.insert(Uuid);
543 // __uuidof can grab UUIDs from template arguments.
544 if (const auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(TD)) {
545 const TemplateArgumentList &TAL = CTSD->getTemplateArgs();
546 for (const TemplateArgument &TA : TAL.asArray()) {
547 const UuidAttr *UuidForTA = nullptr;
548 if (TA.getKind() == TemplateArgument::Type)
549 getUuidAttrOfType(SemaRef, TA.getAsType(), UuidAttrs);
550 else if (TA.getKind() == TemplateArgument::Declaration)
551 getUuidAttrOfType(SemaRef, TA.getAsDecl()->getType(), UuidAttrs);
554 UuidAttrs.insert(UuidForTA);
559 /// \brief Build a Microsoft __uuidof expression with a type operand.
560 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType,
561 SourceLocation TypeidLoc,
562 TypeSourceInfo *Operand,
563 SourceLocation RParenLoc) {
565 if (!Operand->getType()->isDependentType()) {
566 llvm::SmallSetVector<const UuidAttr *, 1> UuidAttrs;
567 getUuidAttrOfType(*this, Operand->getType(), UuidAttrs);
568 if (UuidAttrs.empty())
569 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
570 if (UuidAttrs.size() > 1)
571 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
572 UuidStr = UuidAttrs.back()->getGuid();
575 return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), Operand, UuidStr,
576 SourceRange(TypeidLoc, RParenLoc));
579 /// \brief Build a Microsoft __uuidof expression with an expression operand.
580 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType,
581 SourceLocation TypeidLoc,
583 SourceLocation RParenLoc) {
585 if (!E->getType()->isDependentType()) {
586 if (E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
587 UuidStr = "00000000-0000-0000-0000-000000000000";
589 llvm::SmallSetVector<const UuidAttr *, 1> UuidAttrs;
590 getUuidAttrOfType(*this, E->getType(), UuidAttrs);
591 if (UuidAttrs.empty())
592 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
593 if (UuidAttrs.size() > 1)
594 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
595 UuidStr = UuidAttrs.back()->getGuid();
599 return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), E, UuidStr,
600 SourceRange(TypeidLoc, RParenLoc));
603 /// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression);
605 Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc,
606 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
607 // If MSVCGuidDecl has not been cached, do the lookup.
609 IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID");
610 LookupResult R(*this, GuidII, SourceLocation(), LookupTagName);
611 LookupQualifiedName(R, Context.getTranslationUnitDecl());
612 MSVCGuidDecl = R.getAsSingle<RecordDecl>();
614 return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof));
617 QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl);
620 // The operand is a type; handle it as such.
621 TypeSourceInfo *TInfo = nullptr;
622 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
628 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
630 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc);
633 // The operand is an expression.
634 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
637 /// ActOnCXXBoolLiteral - Parse {true,false} literals.
639 Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
640 assert((Kind == tok::kw_true || Kind == tok::kw_false) &&
641 "Unknown C++ Boolean value!");
643 CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc);
646 /// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
648 Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) {
649 return new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
652 /// ActOnCXXThrow - Parse throw expressions.
654 Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) {
655 bool IsThrownVarInScope = false;
657 // C++0x [class.copymove]p31:
658 // When certain criteria are met, an implementation is allowed to omit the
659 // copy/move construction of a class object [...]
661 // - in a throw-expression, when the operand is the name of a
662 // non-volatile automatic object (other than a function or catch-
663 // clause parameter) whose scope does not extend beyond the end of the
664 // innermost enclosing try-block (if there is one), the copy/move
665 // operation from the operand to the exception object (15.1) can be
666 // omitted by constructing the automatic object directly into the
668 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens()))
669 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
670 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) {
671 for( ; S; S = S->getParent()) {
672 if (S->isDeclScope(Var)) {
673 IsThrownVarInScope = true;
678 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope |
679 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope |
687 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope);
690 ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex,
691 bool IsThrownVarInScope) {
692 // Don't report an error if 'throw' is used in system headers.
693 if (!getLangOpts().CXXExceptions &&
694 !getSourceManager().isInSystemHeader(OpLoc))
695 Diag(OpLoc, diag::err_exceptions_disabled) << "throw";
697 // Exceptions aren't allowed in CUDA device code.
698 if (getLangOpts().CUDA)
699 CUDADiagIfDeviceCode(OpLoc, diag::err_cuda_device_exceptions)
700 << "throw" << CurrentCUDATarget();
702 if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
703 Diag(OpLoc, diag::err_omp_simd_region_cannot_use_stmt) << "throw";
705 if (Ex && !Ex->isTypeDependent()) {
706 QualType ExceptionObjectTy = Context.getExceptionObjectType(Ex->getType());
707 if (CheckCXXThrowOperand(OpLoc, ExceptionObjectTy, Ex))
710 // Initialize the exception result. This implicitly weeds out
711 // abstract types or types with inaccessible copy constructors.
713 // C++0x [class.copymove]p31:
714 // When certain criteria are met, an implementation is allowed to omit the
715 // copy/move construction of a class object [...]
717 // - in a throw-expression, when the operand is the name of a
718 // non-volatile automatic object (other than a function or
720 // parameter) whose scope does not extend beyond the end of the
721 // innermost enclosing try-block (if there is one), the copy/move
722 // operation from the operand to the exception object (15.1) can be
723 // omitted by constructing the automatic object directly into the
725 const VarDecl *NRVOVariable = nullptr;
726 if (IsThrownVarInScope)
727 NRVOVariable = getCopyElisionCandidate(QualType(), Ex, false);
729 InitializedEntity Entity = InitializedEntity::InitializeException(
730 OpLoc, ExceptionObjectTy,
731 /*NRVO=*/NRVOVariable != nullptr);
732 ExprResult Res = PerformMoveOrCopyInitialization(
733 Entity, NRVOVariable, QualType(), Ex, IsThrownVarInScope);
740 CXXThrowExpr(Ex, Context.VoidTy, OpLoc, IsThrownVarInScope);
744 collectPublicBases(CXXRecordDecl *RD,
745 llvm::DenseMap<CXXRecordDecl *, unsigned> &SubobjectsSeen,
746 llvm::SmallPtrSetImpl<CXXRecordDecl *> &VBases,
747 llvm::SetVector<CXXRecordDecl *> &PublicSubobjectsSeen,
748 bool ParentIsPublic) {
749 for (const CXXBaseSpecifier &BS : RD->bases()) {
750 CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
752 // Virtual bases constitute the same subobject. Non-virtual bases are
753 // always distinct subobjects.
755 NewSubobject = VBases.insert(BaseDecl).second;
760 ++SubobjectsSeen[BaseDecl];
762 // Only add subobjects which have public access throughout the entire chain.
763 bool PublicPath = ParentIsPublic && BS.getAccessSpecifier() == AS_public;
765 PublicSubobjectsSeen.insert(BaseDecl);
767 // Recurse on to each base subobject.
768 collectPublicBases(BaseDecl, SubobjectsSeen, VBases, PublicSubobjectsSeen,
773 static void getUnambiguousPublicSubobjects(
774 CXXRecordDecl *RD, llvm::SmallVectorImpl<CXXRecordDecl *> &Objects) {
775 llvm::DenseMap<CXXRecordDecl *, unsigned> SubobjectsSeen;
776 llvm::SmallSet<CXXRecordDecl *, 2> VBases;
777 llvm::SetVector<CXXRecordDecl *> PublicSubobjectsSeen;
778 SubobjectsSeen[RD] = 1;
779 PublicSubobjectsSeen.insert(RD);
780 collectPublicBases(RD, SubobjectsSeen, VBases, PublicSubobjectsSeen,
781 /*ParentIsPublic=*/true);
783 for (CXXRecordDecl *PublicSubobject : PublicSubobjectsSeen) {
784 // Skip ambiguous objects.
785 if (SubobjectsSeen[PublicSubobject] > 1)
788 Objects.push_back(PublicSubobject);
792 /// CheckCXXThrowOperand - Validate the operand of a throw.
793 bool Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc,
794 QualType ExceptionObjectTy, Expr *E) {
795 // If the type of the exception would be an incomplete type or a pointer
796 // to an incomplete type other than (cv) void the program is ill-formed.
797 QualType Ty = ExceptionObjectTy;
798 bool isPointer = false;
799 if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
800 Ty = Ptr->getPointeeType();
803 if (!isPointer || !Ty->isVoidType()) {
804 if (RequireCompleteType(ThrowLoc, Ty,
805 isPointer ? diag::err_throw_incomplete_ptr
806 : diag::err_throw_incomplete,
807 E->getSourceRange()))
810 if (RequireNonAbstractType(ThrowLoc, ExceptionObjectTy,
811 diag::err_throw_abstract_type, E))
815 // If the exception has class type, we need additional handling.
816 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
820 // If we are throwing a polymorphic class type or pointer thereof,
821 // exception handling will make use of the vtable.
822 MarkVTableUsed(ThrowLoc, RD);
824 // If a pointer is thrown, the referenced object will not be destroyed.
828 // If the class has a destructor, we must be able to call it.
829 if (!RD->hasIrrelevantDestructor()) {
830 if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
831 MarkFunctionReferenced(E->getExprLoc(), Destructor);
832 CheckDestructorAccess(E->getExprLoc(), Destructor,
833 PDiag(diag::err_access_dtor_exception) << Ty);
834 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
839 // The MSVC ABI creates a list of all types which can catch the exception
840 // object. This list also references the appropriate copy constructor to call
841 // if the object is caught by value and has a non-trivial copy constructor.
842 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
843 // We are only interested in the public, unambiguous bases contained within
844 // the exception object. Bases which are ambiguous or otherwise
845 // inaccessible are not catchable types.
846 llvm::SmallVector<CXXRecordDecl *, 2> UnambiguousPublicSubobjects;
847 getUnambiguousPublicSubobjects(RD, UnambiguousPublicSubobjects);
849 for (CXXRecordDecl *Subobject : UnambiguousPublicSubobjects) {
850 // Attempt to lookup the copy constructor. Various pieces of machinery
851 // will spring into action, like template instantiation, which means this
852 // cannot be a simple walk of the class's decls. Instead, we must perform
853 // lookup and overload resolution.
854 CXXConstructorDecl *CD = LookupCopyingConstructor(Subobject, 0);
858 // Mark the constructor referenced as it is used by this throw expression.
859 MarkFunctionReferenced(E->getExprLoc(), CD);
861 // Skip this copy constructor if it is trivial, we don't need to record it
862 // in the catchable type data.
866 // The copy constructor is non-trivial, create a mapping from this class
867 // type to this constructor.
868 // N.B. The selection of copy constructor is not sensitive to this
869 // particular throw-site. Lookup will be performed at the catch-site to
870 // ensure that the copy constructor is, in fact, accessible (via
871 // friendship or any other means).
872 Context.addCopyConstructorForExceptionObject(Subobject, CD);
874 // We don't keep the instantiated default argument expressions around so
875 // we must rebuild them here.
876 for (unsigned I = 1, E = CD->getNumParams(); I != E; ++I) {
877 if (CheckCXXDefaultArgExpr(ThrowLoc, CD, CD->getParamDecl(I)))
886 static QualType adjustCVQualifiersForCXXThisWithinLambda(
887 ArrayRef<FunctionScopeInfo *> FunctionScopes, QualType ThisTy,
888 DeclContext *CurSemaContext, ASTContext &ASTCtx) {
890 QualType ClassType = ThisTy->getPointeeType();
891 LambdaScopeInfo *CurLSI = nullptr;
892 DeclContext *CurDC = CurSemaContext;
894 // Iterate through the stack of lambdas starting from the innermost lambda to
895 // the outermost lambda, checking if '*this' is ever captured by copy - since
896 // that could change the cv-qualifiers of the '*this' object.
897 // The object referred to by '*this' starts out with the cv-qualifiers of its
898 // member function. We then start with the innermost lambda and iterate
899 // outward checking to see if any lambda performs a by-copy capture of '*this'
900 // - and if so, any nested lambda must respect the 'constness' of that
901 // capturing lamdbda's call operator.
904 // The issue is that we cannot rely entirely on the FunctionScopeInfo stack
905 // since ScopeInfos are pushed on during parsing and treetransforming. But
906 // since a generic lambda's call operator can be instantiated anywhere (even
907 // end of the TU) we need to be able to examine its enclosing lambdas and so
908 // we use the DeclContext to get a hold of the closure-class and query it for
909 // capture information. The reason we don't just resort to always using the
910 // DeclContext chain is that it is only mature for lambda expressions
911 // enclosing generic lambda's call operators that are being instantiated.
913 for (int I = FunctionScopes.size();
914 I-- && isa<LambdaScopeInfo>(FunctionScopes[I]);
915 CurDC = getLambdaAwareParentOfDeclContext(CurDC)) {
916 CurLSI = cast<LambdaScopeInfo>(FunctionScopes[I]);
918 if (!CurLSI->isCXXThisCaptured())
921 auto C = CurLSI->getCXXThisCapture();
923 if (C.isCopyCapture()) {
924 ClassType.removeLocalCVRQualifiers(Qualifiers::CVRMask);
925 if (CurLSI->CallOperator->isConst())
926 ClassType.addConst();
927 return ASTCtx.getPointerType(ClassType);
930 // We've run out of ScopeInfos but check if CurDC is a lambda (which can
931 // happen during instantiation of generic lambdas)
932 if (isLambdaCallOperator(CurDC)) {
934 assert(isGenericLambdaCallOperatorSpecialization(CurLSI->CallOperator));
935 assert(CurDC == getLambdaAwareParentOfDeclContext(CurLSI->CallOperator));
937 auto IsThisCaptured =
938 [](CXXRecordDecl *Closure, bool &IsByCopy, bool &IsConst) {
941 for (auto &&C : Closure->captures()) {
942 if (C.capturesThis()) {
943 if (C.getCaptureKind() == LCK_StarThis)
945 if (Closure->getLambdaCallOperator()->isConst())
953 bool IsByCopyCapture = false;
954 bool IsConstCapture = false;
955 CXXRecordDecl *Closure = cast<CXXRecordDecl>(CurDC->getParent());
957 IsThisCaptured(Closure, IsByCopyCapture, IsConstCapture)) {
958 if (IsByCopyCapture) {
959 ClassType.removeLocalCVRQualifiers(Qualifiers::CVRMask);
961 ClassType.addConst();
962 return ASTCtx.getPointerType(ClassType);
964 Closure = isLambdaCallOperator(Closure->getParent())
965 ? cast<CXXRecordDecl>(Closure->getParent()->getParent())
969 return ASTCtx.getPointerType(ClassType);
972 QualType Sema::getCurrentThisType() {
973 DeclContext *DC = getFunctionLevelDeclContext();
974 QualType ThisTy = CXXThisTypeOverride;
976 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) {
977 if (method && method->isInstance())
978 ThisTy = method->getThisType(Context);
981 if (ThisTy.isNull() && isLambdaCallOperator(CurContext) &&
982 inTemplateInstantiation()) {
984 assert(isa<CXXRecordDecl>(DC) &&
985 "Trying to get 'this' type from static method?");
987 // This is a lambda call operator that is being instantiated as a default
988 // initializer. DC must point to the enclosing class type, so we can recover
989 // the 'this' type from it.
991 QualType ClassTy = Context.getTypeDeclType(cast<CXXRecordDecl>(DC));
992 // There are no cv-qualifiers for 'this' within default initializers,
993 // per [expr.prim.general]p4.
994 ThisTy = Context.getPointerType(ClassTy);
997 // If we are within a lambda's call operator, the cv-qualifiers of 'this'
998 // might need to be adjusted if the lambda or any of its enclosing lambda's
999 // captures '*this' by copy.
1000 if (!ThisTy.isNull() && isLambdaCallOperator(CurContext))
1001 return adjustCVQualifiersForCXXThisWithinLambda(FunctionScopes, ThisTy,
1002 CurContext, Context);
1006 Sema::CXXThisScopeRAII::CXXThisScopeRAII(Sema &S,
1008 unsigned CXXThisTypeQuals,
1010 : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false)
1012 if (!Enabled || !ContextDecl)
1015 CXXRecordDecl *Record = nullptr;
1016 if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl))
1017 Record = Template->getTemplatedDecl();
1019 Record = cast<CXXRecordDecl>(ContextDecl);
1021 // We care only for CVR qualifiers here, so cut everything else.
1022 CXXThisTypeQuals &= Qualifiers::FastMask;
1023 S.CXXThisTypeOverride
1024 = S.Context.getPointerType(
1025 S.Context.getRecordType(Record).withCVRQualifiers(CXXThisTypeQuals));
1027 this->Enabled = true;
1031 Sema::CXXThisScopeRAII::~CXXThisScopeRAII() {
1033 S.CXXThisTypeOverride = OldCXXThisTypeOverride;
1037 static Expr *captureThis(Sema &S, ASTContext &Context, RecordDecl *RD,
1038 QualType ThisTy, SourceLocation Loc,
1039 const bool ByCopy) {
1041 QualType AdjustedThisTy = ThisTy;
1042 // The type of the corresponding data member (not a 'this' pointer if 'by
1044 QualType CaptureThisFieldTy = ThisTy;
1046 // If we are capturing the object referred to by '*this' by copy, ignore any
1047 // cv qualifiers inherited from the type of the member function for the type
1048 // of the closure-type's corresponding data member and any use of 'this'.
1049 CaptureThisFieldTy = ThisTy->getPointeeType();
1050 CaptureThisFieldTy.removeLocalCVRQualifiers(Qualifiers::CVRMask);
1051 AdjustedThisTy = Context.getPointerType(CaptureThisFieldTy);
1054 FieldDecl *Field = FieldDecl::Create(
1055 Context, RD, Loc, Loc, nullptr, CaptureThisFieldTy,
1056 Context.getTrivialTypeSourceInfo(CaptureThisFieldTy, Loc), nullptr, false,
1059 Field->setImplicit(true);
1060 Field->setAccess(AS_private);
1063 new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit*/ true);
1065 Expr *StarThis = S.CreateBuiltinUnaryOp(Loc,
1068 InitializedEntity Entity = InitializedEntity::InitializeLambdaCapture(
1069 nullptr, CaptureThisFieldTy, Loc);
1070 InitializationKind InitKind = InitializationKind::CreateDirect(Loc, Loc, Loc);
1071 InitializationSequence Init(S, Entity, InitKind, StarThis);
1072 ExprResult ER = Init.Perform(S, Entity, InitKind, StarThis);
1073 if (ER.isInvalid()) return nullptr;
1079 bool Sema::CheckCXXThisCapture(SourceLocation Loc, const bool Explicit,
1080 bool BuildAndDiagnose, const unsigned *const FunctionScopeIndexToStopAt,
1081 const bool ByCopy) {
1082 // We don't need to capture this in an unevaluated context.
1083 if (isUnevaluatedContext() && !Explicit)
1086 assert((!ByCopy || Explicit) && "cannot implicitly capture *this by value");
1088 const unsigned MaxFunctionScopesIndex = FunctionScopeIndexToStopAt ?
1089 *FunctionScopeIndexToStopAt : FunctionScopes.size() - 1;
1091 // Check that we can capture the *enclosing object* (referred to by '*this')
1092 // by the capturing-entity/closure (lambda/block/etc) at
1093 // MaxFunctionScopesIndex-deep on the FunctionScopes stack.
1095 // Note: The *enclosing object* can only be captured by-value by a
1096 // closure that is a lambda, using the explicit notation:
1098 // Every other capture of the *enclosing object* results in its by-reference
1101 // For a closure 'L' (at MaxFunctionScopesIndex in the FunctionScopes
1102 // stack), we can capture the *enclosing object* only if:
1103 // - 'L' has an explicit byref or byval capture of the *enclosing object*
1104 // - or, 'L' has an implicit capture.
1106 // -- there is no enclosing closure
1107 // -- or, there is some enclosing closure 'E' that has already captured the
1108 // *enclosing object*, and every intervening closure (if any) between 'E'
1109 // and 'L' can implicitly capture the *enclosing object*.
1110 // -- or, every enclosing closure can implicitly capture the
1111 // *enclosing object*
1114 unsigned NumCapturingClosures = 0;
1115 for (unsigned idx = MaxFunctionScopesIndex; idx != 0; idx--) {
1116 if (CapturingScopeInfo *CSI =
1117 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) {
1118 if (CSI->CXXThisCaptureIndex != 0) {
1119 // 'this' is already being captured; there isn't anything more to do.
1120 CSI->Captures[CSI->CXXThisCaptureIndex - 1].markUsed(BuildAndDiagnose);
1123 LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI);
1124 if (LSI && isGenericLambdaCallOperatorSpecialization(LSI->CallOperator)) {
1125 // This context can't implicitly capture 'this'; fail out.
1126 if (BuildAndDiagnose)
1127 Diag(Loc, diag::err_this_capture)
1128 << (Explicit && idx == MaxFunctionScopesIndex);
1131 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref ||
1132 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval ||
1133 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block ||
1134 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_CapturedRegion ||
1135 (Explicit && idx == MaxFunctionScopesIndex)) {
1136 // Regarding (Explicit && idx == MaxFunctionScopesIndex): only the first
1137 // iteration through can be an explicit capture, all enclosing closures,
1138 // if any, must perform implicit captures.
1140 // This closure can capture 'this'; continue looking upwards.
1141 NumCapturingClosures++;
1144 // This context can't implicitly capture 'this'; fail out.
1145 if (BuildAndDiagnose)
1146 Diag(Loc, diag::err_this_capture)
1147 << (Explicit && idx == MaxFunctionScopesIndex);
1152 if (!BuildAndDiagnose) return false;
1154 // If we got here, then the closure at MaxFunctionScopesIndex on the
1155 // FunctionScopes stack, can capture the *enclosing object*, so capture it
1156 // (including implicit by-reference captures in any enclosing closures).
1158 // In the loop below, respect the ByCopy flag only for the closure requesting
1159 // the capture (i.e. first iteration through the loop below). Ignore it for
1160 // all enclosing closure's up to NumCapturingClosures (since they must be
1161 // implicitly capturing the *enclosing object* by reference (see loop
1164 dyn_cast<LambdaScopeInfo>(FunctionScopes[MaxFunctionScopesIndex])) &&
1165 "Only a lambda can capture the enclosing object (referred to by "
1167 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated
1169 QualType ThisTy = getCurrentThisType();
1170 for (unsigned idx = MaxFunctionScopesIndex; NumCapturingClosures;
1171 --idx, --NumCapturingClosures) {
1172 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]);
1173 Expr *ThisExpr = nullptr;
1175 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI)) {
1176 // For lambda expressions, build a field and an initializing expression,
1177 // and capture the *enclosing object* by copy only if this is the first
1179 ThisExpr = captureThis(*this, Context, LSI->Lambda, ThisTy, Loc,
1180 ByCopy && idx == MaxFunctionScopesIndex);
1182 } else if (CapturedRegionScopeInfo *RSI
1183 = dyn_cast<CapturedRegionScopeInfo>(FunctionScopes[idx]))
1185 captureThis(*this, Context, RSI->TheRecordDecl, ThisTy, Loc,
1188 bool isNested = NumCapturingClosures > 1;
1189 CSI->addThisCapture(isNested, Loc, ThisExpr, ByCopy);
1194 ExprResult Sema::ActOnCXXThis(SourceLocation Loc) {
1195 /// C++ 9.3.2: In the body of a non-static member function, the keyword this
1196 /// is a non-lvalue expression whose value is the address of the object for
1197 /// which the function is called.
1199 QualType ThisTy = getCurrentThisType();
1200 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use);
1202 CheckCXXThisCapture(Loc);
1203 return new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false);
1206 bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) {
1207 // If we're outside the body of a member function, then we'll have a specified
1209 if (CXXThisTypeOverride.isNull())
1212 // Determine whether we're looking into a class that's currently being
1214 CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl();
1215 return Class && Class->isBeingDefined();
1219 Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep,
1220 SourceLocation LParenLoc,
1222 SourceLocation RParenLoc) {
1226 TypeSourceInfo *TInfo;
1227 QualType Ty = GetTypeFromParser(TypeRep, &TInfo);
1229 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation());
1231 auto Result = BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc);
1232 // Avoid creating a non-type-dependent expression that contains typos.
1233 // Non-type-dependent expressions are liable to be discarded without
1234 // checking for embedded typos.
1235 if (!Result.isInvalid() && Result.get()->isInstantiationDependent() &&
1236 !Result.get()->isTypeDependent())
1237 Result = CorrectDelayedTyposInExpr(Result.get());
1241 /// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
1242 /// Can be interpreted either as function-style casting ("int(x)")
1243 /// or class type construction ("ClassType(x,y,z)")
1244 /// or creation of a value-initialized type ("int()").
1246 Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo,
1247 SourceLocation LParenLoc,
1249 SourceLocation RParenLoc) {
1250 QualType Ty = TInfo->getType();
1251 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc();
1253 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(Exprs)) {
1254 return CXXUnresolvedConstructExpr::Create(Context, TInfo, LParenLoc, Exprs,
1258 bool ListInitialization = LParenLoc.isInvalid();
1259 assert((!ListInitialization ||
1260 (Exprs.size() == 1 && isa<InitListExpr>(Exprs[0]))) &&
1261 "List initialization must have initializer list as expression.");
1262 SourceRange FullRange = SourceRange(TyBeginLoc,
1263 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc);
1265 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo);
1266 InitializationKind Kind =
1268 ? ListInitialization
1269 ? InitializationKind::CreateDirectList(TyBeginLoc)
1270 : InitializationKind::CreateDirect(TyBeginLoc, LParenLoc,
1272 : InitializationKind::CreateValue(TyBeginLoc, LParenLoc, RParenLoc);
1274 // C++1z [expr.type.conv]p1:
1275 // If the type is a placeholder for a deduced class type, [...perform class
1276 // template argument deduction...]
1277 DeducedType *Deduced = Ty->getContainedDeducedType();
1278 if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
1279 Ty = DeduceTemplateSpecializationFromInitializer(TInfo, Entity,
1283 Entity = InitializedEntity::InitializeTemporary(TInfo, Ty);
1286 // C++ [expr.type.conv]p1:
1287 // If the expression list is a parenthesized single expression, the type
1288 // conversion expression is equivalent (in definedness, and if defined in
1289 // meaning) to the corresponding cast expression.
1290 if (Exprs.size() == 1 && !ListInitialization &&
1291 !isa<InitListExpr>(Exprs[0])) {
1292 Expr *Arg = Exprs[0];
1293 return BuildCXXFunctionalCastExpr(TInfo, Ty, LParenLoc, Arg, RParenLoc);
1296 // For an expression of the form T(), T shall not be an array type.
1297 QualType ElemTy = Ty;
1298 if (Ty->isArrayType()) {
1299 if (!ListInitialization)
1300 return ExprError(Diag(TyBeginLoc, diag::err_value_init_for_array_type)
1302 ElemTy = Context.getBaseElementType(Ty);
1305 // There doesn't seem to be an explicit rule against this but sanity demands
1306 // we only construct objects with object types.
1307 if (Ty->isFunctionType())
1308 return ExprError(Diag(TyBeginLoc, diag::err_init_for_function_type)
1309 << Ty << FullRange);
1311 // C++17 [expr.type.conv]p2:
1312 // If the type is cv void and the initializer is (), the expression is a
1313 // prvalue of the specified type that performs no initialization.
1314 if (!Ty->isVoidType() &&
1315 RequireCompleteType(TyBeginLoc, ElemTy,
1316 diag::err_invalid_incomplete_type_use, FullRange))
1319 // Otherwise, the expression is a prvalue of the specified type whose
1320 // result object is direct-initialized (11.6) with the initializer.
1321 InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
1322 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Exprs);
1324 if (Result.isInvalid())
1327 Expr *Inner = Result.get();
1328 if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Inner))
1329 Inner = BTE->getSubExpr();
1330 if (!isa<CXXTemporaryObjectExpr>(Inner) &&
1331 !isa<CXXScalarValueInitExpr>(Inner)) {
1332 // If we created a CXXTemporaryObjectExpr, that node also represents the
1333 // functional cast. Otherwise, create an explicit cast to represent
1334 // the syntactic form of a functional-style cast that was used here.
1336 // FIXME: Creating a CXXFunctionalCastExpr around a CXXConstructExpr
1337 // would give a more consistent AST representation than using a
1338 // CXXTemporaryObjectExpr. It's also weird that the functional cast
1339 // is sometimes handled by initialization and sometimes not.
1340 QualType ResultType = Result.get()->getType();
1341 Result = CXXFunctionalCastExpr::Create(
1342 Context, ResultType, Expr::getValueKindForType(Ty), TInfo,
1343 CK_NoOp, Result.get(), /*Path=*/nullptr, LParenLoc, RParenLoc);
1349 /// \brief Determine whether the given function is a non-placement
1350 /// deallocation function.
1351 static bool isNonPlacementDeallocationFunction(Sema &S, FunctionDecl *FD) {
1352 if (FD->isInvalidDecl())
1355 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD))
1356 return Method->isUsualDeallocationFunction();
1358 if (FD->getOverloadedOperator() != OO_Delete &&
1359 FD->getOverloadedOperator() != OO_Array_Delete)
1362 unsigned UsualParams = 1;
1364 if (S.getLangOpts().SizedDeallocation && UsualParams < FD->getNumParams() &&
1365 S.Context.hasSameUnqualifiedType(
1366 FD->getParamDecl(UsualParams)->getType(),
1367 S.Context.getSizeType()))
1370 if (S.getLangOpts().AlignedAllocation && UsualParams < FD->getNumParams() &&
1371 S.Context.hasSameUnqualifiedType(
1372 FD->getParamDecl(UsualParams)->getType(),
1373 S.Context.getTypeDeclType(S.getStdAlignValT())))
1376 return UsualParams == FD->getNumParams();
1380 struct UsualDeallocFnInfo {
1381 UsualDeallocFnInfo() : Found(), FD(nullptr) {}
1382 UsualDeallocFnInfo(Sema &S, DeclAccessPair Found)
1383 : Found(Found), FD(dyn_cast<FunctionDecl>(Found->getUnderlyingDecl())),
1384 HasSizeT(false), HasAlignValT(false), CUDAPref(Sema::CFP_Native) {
1385 // A function template declaration is never a usual deallocation function.
1388 if (FD->getNumParams() == 3)
1389 HasAlignValT = HasSizeT = true;
1390 else if (FD->getNumParams() == 2) {
1391 HasSizeT = FD->getParamDecl(1)->getType()->isIntegerType();
1392 HasAlignValT = !HasSizeT;
1395 // In CUDA, determine how much we'd like / dislike to call this.
1396 if (S.getLangOpts().CUDA)
1397 if (auto *Caller = dyn_cast<FunctionDecl>(S.CurContext))
1398 CUDAPref = S.IdentifyCUDAPreference(Caller, FD);
1401 operator bool() const { return FD; }
1403 bool isBetterThan(const UsualDeallocFnInfo &Other, bool WantSize,
1404 bool WantAlign) const {
1405 // C++17 [expr.delete]p10:
1406 // If the type has new-extended alignment, a function with a parameter
1407 // of type std::align_val_t is preferred; otherwise a function without
1408 // such a parameter is preferred
1409 if (HasAlignValT != Other.HasAlignValT)
1410 return HasAlignValT == WantAlign;
1412 if (HasSizeT != Other.HasSizeT)
1413 return HasSizeT == WantSize;
1415 // Use CUDA call preference as a tiebreaker.
1416 return CUDAPref > Other.CUDAPref;
1419 DeclAccessPair Found;
1421 bool HasSizeT, HasAlignValT;
1422 Sema::CUDAFunctionPreference CUDAPref;
1426 /// Determine whether a type has new-extended alignment. This may be called when
1427 /// the type is incomplete (for a delete-expression with an incomplete pointee
1428 /// type), in which case it will conservatively return false if the alignment is
1430 static bool hasNewExtendedAlignment(Sema &S, QualType AllocType) {
1431 return S.getLangOpts().AlignedAllocation &&
1432 S.getASTContext().getTypeAlignIfKnown(AllocType) >
1433 S.getASTContext().getTargetInfo().getNewAlign();
1436 /// Select the correct "usual" deallocation function to use from a selection of
1437 /// deallocation functions (either global or class-scope).
1438 static UsualDeallocFnInfo resolveDeallocationOverload(
1439 Sema &S, LookupResult &R, bool WantSize, bool WantAlign,
1440 llvm::SmallVectorImpl<UsualDeallocFnInfo> *BestFns = nullptr) {
1441 UsualDeallocFnInfo Best;
1443 for (auto I = R.begin(), E = R.end(); I != E; ++I) {
1444 UsualDeallocFnInfo Info(S, I.getPair());
1445 if (!Info || !isNonPlacementDeallocationFunction(S, Info.FD) ||
1446 Info.CUDAPref == Sema::CFP_Never)
1452 BestFns->push_back(Info);
1456 if (Best.isBetterThan(Info, WantSize, WantAlign))
1459 // If more than one preferred function is found, all non-preferred
1460 // functions are eliminated from further consideration.
1461 if (BestFns && Info.isBetterThan(Best, WantSize, WantAlign))
1466 BestFns->push_back(Info);
1472 /// Determine whether a given type is a class for which 'delete[]' would call
1473 /// a member 'operator delete[]' with a 'size_t' parameter. This implies that
1474 /// we need to store the array size (even if the type is
1475 /// trivially-destructible).
1476 static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc,
1477 QualType allocType) {
1478 const RecordType *record =
1479 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>();
1480 if (!record) return false;
1482 // Try to find an operator delete[] in class scope.
1484 DeclarationName deleteName =
1485 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete);
1486 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName);
1487 S.LookupQualifiedName(ops, record->getDecl());
1489 // We're just doing this for information.
1490 ops.suppressDiagnostics();
1492 // Very likely: there's no operator delete[].
1493 if (ops.empty()) return false;
1495 // If it's ambiguous, it should be illegal to call operator delete[]
1496 // on this thing, so it doesn't matter if we allocate extra space or not.
1497 if (ops.isAmbiguous()) return false;
1499 // C++17 [expr.delete]p10:
1500 // If the deallocation functions have class scope, the one without a
1501 // parameter of type std::size_t is selected.
1502 auto Best = resolveDeallocationOverload(
1503 S, ops, /*WantSize*/false,
1504 /*WantAlign*/hasNewExtendedAlignment(S, allocType));
1505 return Best && Best.HasSizeT;
1508 /// \brief Parsed a C++ 'new' expression (C++ 5.3.4).
1511 /// @code new (memory) int[size][4] @endcode
1513 /// @code ::new Foo(23, "hello") @endcode
1515 /// \param StartLoc The first location of the expression.
1516 /// \param UseGlobal True if 'new' was prefixed with '::'.
1517 /// \param PlacementLParen Opening paren of the placement arguments.
1518 /// \param PlacementArgs Placement new arguments.
1519 /// \param PlacementRParen Closing paren of the placement arguments.
1520 /// \param TypeIdParens If the type is in parens, the source range.
1521 /// \param D The type to be allocated, as well as array dimensions.
1522 /// \param Initializer The initializing expression or initializer-list, or null
1523 /// if there is none.
1525 Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
1526 SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
1527 SourceLocation PlacementRParen, SourceRange TypeIdParens,
1528 Declarator &D, Expr *Initializer) {
1529 Expr *ArraySize = nullptr;
1530 // If the specified type is an array, unwrap it and save the expression.
1531 if (D.getNumTypeObjects() > 0 &&
1532 D.getTypeObject(0).Kind == DeclaratorChunk::Array) {
1533 DeclaratorChunk &Chunk = D.getTypeObject(0);
1534 if (D.getDeclSpec().hasAutoTypeSpec())
1535 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto)
1536 << D.getSourceRange());
1537 if (Chunk.Arr.hasStatic)
1538 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
1539 << D.getSourceRange());
1540 if (!Chunk.Arr.NumElts)
1541 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
1542 << D.getSourceRange());
1544 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
1545 D.DropFirstTypeObject();
1548 // Every dimension shall be of constant size.
1550 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
1551 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array)
1554 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr;
1555 if (Expr *NumElts = (Expr *)Array.NumElts) {
1556 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
1557 if (getLangOpts().CPlusPlus14) {
1558 // C++1y [expr.new]p6: Every constant-expression in a noptr-new-declarator
1559 // shall be a converted constant expression (5.19) of type std::size_t
1560 // and shall evaluate to a strictly positive value.
1561 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
1562 assert(IntWidth && "Builtin type of size 0?");
1563 llvm::APSInt Value(IntWidth);
1565 = CheckConvertedConstantExpression(NumElts, Context.getSizeType(), Value,
1570 = VerifyIntegerConstantExpression(NumElts, nullptr,
1571 diag::err_new_array_nonconst)
1581 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/nullptr);
1582 QualType AllocType = TInfo->getType();
1583 if (D.isInvalidType())
1586 SourceRange DirectInitRange;
1587 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer))
1588 DirectInitRange = List->getSourceRange();
1590 return BuildCXXNew(SourceRange(StartLoc, D.getLocEnd()), UseGlobal,
1602 static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style,
1606 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init))
1607 return PLE->getNumExprs() == 0;
1608 if (isa<ImplicitValueInitExpr>(Init))
1610 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init))
1611 return !CCE->isListInitialization() &&
1612 CCE->getConstructor()->isDefaultConstructor();
1613 else if (Style == CXXNewExpr::ListInit) {
1614 assert(isa<InitListExpr>(Init) &&
1615 "Shouldn't create list CXXConstructExprs for arrays.");
1622 Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
1623 SourceLocation PlacementLParen,
1624 MultiExprArg PlacementArgs,
1625 SourceLocation PlacementRParen,
1626 SourceRange TypeIdParens,
1628 TypeSourceInfo *AllocTypeInfo,
1630 SourceRange DirectInitRange,
1631 Expr *Initializer) {
1632 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange();
1633 SourceLocation StartLoc = Range.getBegin();
1635 CXXNewExpr::InitializationStyle initStyle;
1636 if (DirectInitRange.isValid()) {
1637 assert(Initializer && "Have parens but no initializer.");
1638 initStyle = CXXNewExpr::CallInit;
1639 } else if (Initializer && isa<InitListExpr>(Initializer))
1640 initStyle = CXXNewExpr::ListInit;
1642 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) ||
1643 isa<CXXConstructExpr>(Initializer)) &&
1644 "Initializer expression that cannot have been implicitly created.");
1645 initStyle = CXXNewExpr::NoInit;
1648 Expr **Inits = &Initializer;
1649 unsigned NumInits = Initializer ? 1 : 0;
1650 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) {
1651 assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init");
1652 Inits = List->getExprs();
1653 NumInits = List->getNumExprs();
1656 // C++11 [expr.new]p15:
1657 // A new-expression that creates an object of type T initializes that
1658 // object as follows:
1659 InitializationKind Kind
1660 // - If the new-initializer is omitted, the object is default-
1661 // initialized (8.5); if no initialization is performed,
1662 // the object has indeterminate value
1663 = initStyle == CXXNewExpr::NoInit
1664 ? InitializationKind::CreateDefault(TypeRange.getBegin())
1665 // - Otherwise, the new-initializer is interpreted according to the
1666 // initialization rules of 8.5 for direct-initialization.
1667 : initStyle == CXXNewExpr::ListInit
1668 ? InitializationKind::CreateDirectList(TypeRange.getBegin())
1669 : InitializationKind::CreateDirect(TypeRange.getBegin(),
1670 DirectInitRange.getBegin(),
1671 DirectInitRange.getEnd());
1673 // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
1674 auto *Deduced = AllocType->getContainedDeducedType();
1675 if (Deduced && isa<DeducedTemplateSpecializationType>(Deduced)) {
1677 return ExprError(Diag(ArraySize->getExprLoc(),
1678 diag::err_deduced_class_template_compound_type)
1679 << /*array*/ 2 << ArraySize->getSourceRange());
1681 InitializedEntity Entity
1682 = InitializedEntity::InitializeNew(StartLoc, AllocType);
1683 AllocType = DeduceTemplateSpecializationFromInitializer(
1684 AllocTypeInfo, Entity, Kind, MultiExprArg(Inits, NumInits));
1685 if (AllocType.isNull())
1687 } else if (Deduced) {
1688 if (initStyle == CXXNewExpr::NoInit || NumInits == 0)
1689 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg)
1690 << AllocType << TypeRange);
1691 if (initStyle == CXXNewExpr::ListInit ||
1692 (NumInits == 1 && isa<InitListExpr>(Inits[0])))
1693 return ExprError(Diag(Inits[0]->getLocStart(),
1694 diag::err_auto_new_list_init)
1695 << AllocType << TypeRange);
1697 Expr *FirstBad = Inits[1];
1698 return ExprError(Diag(FirstBad->getLocStart(),
1699 diag::err_auto_new_ctor_multiple_expressions)
1700 << AllocType << TypeRange);
1702 Expr *Deduce = Inits[0];
1703 QualType DeducedType;
1704 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed)
1705 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure)
1706 << AllocType << Deduce->getType()
1707 << TypeRange << Deduce->getSourceRange());
1708 if (DeducedType.isNull())
1710 AllocType = DeducedType;
1713 // Per C++0x [expr.new]p5, the type being constructed may be a
1714 // typedef of an array type.
1716 if (const ConstantArrayType *Array
1717 = Context.getAsConstantArrayType(AllocType)) {
1718 ArraySize = IntegerLiteral::Create(Context, Array->getSize(),
1719 Context.getSizeType(),
1720 TypeRange.getEnd());
1721 AllocType = Array->getElementType();
1725 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange))
1728 if (initStyle == CXXNewExpr::ListInit &&
1729 isStdInitializerList(AllocType, nullptr)) {
1730 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(),
1731 diag::warn_dangling_std_initializer_list)
1732 << /*at end of FE*/0 << Inits[0]->getSourceRange();
1735 // In ARC, infer 'retaining' for the allocated
1736 if (getLangOpts().ObjCAutoRefCount &&
1737 AllocType.getObjCLifetime() == Qualifiers::OCL_None &&
1738 AllocType->isObjCLifetimeType()) {
1739 AllocType = Context.getLifetimeQualifiedType(AllocType,
1740 AllocType->getObjCARCImplicitLifetime());
1743 QualType ResultType = Context.getPointerType(AllocType);
1745 if (ArraySize && ArraySize->getType()->isNonOverloadPlaceholderType()) {
1746 ExprResult result = CheckPlaceholderExpr(ArraySize);
1747 if (result.isInvalid()) return ExprError();
1748 ArraySize = result.get();
1750 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have
1751 // integral or enumeration type with a non-negative value."
1752 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped
1753 // enumeration type, or a class type for which a single non-explicit
1754 // conversion function to integral or unscoped enumeration type exists.
1755 // C++1y [expr.new]p6: The expression [...] is implicitly converted to
1757 llvm::Optional<uint64_t> KnownArraySize;
1758 if (ArraySize && !ArraySize->isTypeDependent()) {
1759 ExprResult ConvertedSize;
1760 if (getLangOpts().CPlusPlus14) {
1761 assert(Context.getTargetInfo().getIntWidth() && "Builtin type of size 0?");
1763 ConvertedSize = PerformImplicitConversion(ArraySize, Context.getSizeType(),
1766 if (!ConvertedSize.isInvalid() &&
1767 ArraySize->getType()->getAs<RecordType>())
1768 // Diagnose the compatibility of this conversion.
1769 Diag(StartLoc, diag::warn_cxx98_compat_array_size_conversion)
1770 << ArraySize->getType() << 0 << "'size_t'";
1772 class SizeConvertDiagnoser : public ICEConvertDiagnoser {
1777 SizeConvertDiagnoser(Expr *ArraySize)
1778 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false, false, false),
1779 ArraySize(ArraySize) {}
1781 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
1782 QualType T) override {
1783 return S.Diag(Loc, diag::err_array_size_not_integral)
1784 << S.getLangOpts().CPlusPlus11 << T;
1787 SemaDiagnosticBuilder diagnoseIncomplete(
1788 Sema &S, SourceLocation Loc, QualType T) override {
1789 return S.Diag(Loc, diag::err_array_size_incomplete_type)
1790 << T << ArraySize->getSourceRange();
1793 SemaDiagnosticBuilder diagnoseExplicitConv(
1794 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
1795 return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy;
1798 SemaDiagnosticBuilder noteExplicitConv(
1799 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1800 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1801 << ConvTy->isEnumeralType() << ConvTy;
1804 SemaDiagnosticBuilder diagnoseAmbiguous(
1805 Sema &S, SourceLocation Loc, QualType T) override {
1806 return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T;
1809 SemaDiagnosticBuilder noteAmbiguous(
1810 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1811 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1812 << ConvTy->isEnumeralType() << ConvTy;
1815 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
1817 QualType ConvTy) override {
1819 S.getLangOpts().CPlusPlus11
1820 ? diag::warn_cxx98_compat_array_size_conversion
1821 : diag::ext_array_size_conversion)
1822 << T << ConvTy->isEnumeralType() << ConvTy;
1824 } SizeDiagnoser(ArraySize);
1826 ConvertedSize = PerformContextualImplicitConversion(StartLoc, ArraySize,
1829 if (ConvertedSize.isInvalid())
1832 ArraySize = ConvertedSize.get();
1833 QualType SizeType = ArraySize->getType();
1835 if (!SizeType->isIntegralOrUnscopedEnumerationType())
1838 // C++98 [expr.new]p7:
1839 // The expression in a direct-new-declarator shall have integral type
1840 // with a non-negative value.
1842 // Let's see if this is a constant < 0. If so, we reject it out of hand,
1843 // per CWG1464. Otherwise, if it's not a constant, we must have an
1844 // unparenthesized array type.
1845 if (!ArraySize->isValueDependent()) {
1847 // We've already performed any required implicit conversion to integer or
1848 // unscoped enumeration type.
1849 // FIXME: Per CWG1464, we are required to check the value prior to
1850 // converting to size_t. This will never find a negative array size in
1851 // C++14 onwards, because Value is always unsigned here!
1852 if (ArraySize->isIntegerConstantExpr(Value, Context)) {
1853 if (Value.isSigned() && Value.isNegative()) {
1854 return ExprError(Diag(ArraySize->getLocStart(),
1855 diag::err_typecheck_negative_array_size)
1856 << ArraySize->getSourceRange());
1859 if (!AllocType->isDependentType()) {
1860 unsigned ActiveSizeBits =
1861 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value);
1862 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context))
1863 return ExprError(Diag(ArraySize->getLocStart(),
1864 diag::err_array_too_large)
1865 << Value.toString(10)
1866 << ArraySize->getSourceRange());
1869 KnownArraySize = Value.getZExtValue();
1870 } else if (TypeIdParens.isValid()) {
1871 // Can't have dynamic array size when the type-id is in parentheses.
1872 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst)
1873 << ArraySize->getSourceRange()
1874 << FixItHint::CreateRemoval(TypeIdParens.getBegin())
1875 << FixItHint::CreateRemoval(TypeIdParens.getEnd());
1877 TypeIdParens = SourceRange();
1881 // Note that we do *not* convert the argument in any way. It can
1882 // be signed, larger than size_t, whatever.
1885 FunctionDecl *OperatorNew = nullptr;
1886 FunctionDecl *OperatorDelete = nullptr;
1887 unsigned Alignment =
1888 AllocType->isDependentType() ? 0 : Context.getTypeAlign(AllocType);
1889 unsigned NewAlignment = Context.getTargetInfo().getNewAlign();
1890 bool PassAlignment = getLangOpts().AlignedAllocation &&
1891 Alignment > NewAlignment;
1893 if (!AllocType->isDependentType() &&
1894 !Expr::hasAnyTypeDependentArguments(PlacementArgs) &&
1895 FindAllocationFunctions(StartLoc,
1896 SourceRange(PlacementLParen, PlacementRParen),
1897 UseGlobal, AllocType, ArraySize, PassAlignment,
1898 PlacementArgs, OperatorNew, OperatorDelete))
1901 // If this is an array allocation, compute whether the usual array
1902 // deallocation function for the type has a size_t parameter.
1903 bool UsualArrayDeleteWantsSize = false;
1904 if (ArraySize && !AllocType->isDependentType())
1905 UsualArrayDeleteWantsSize =
1906 doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType);
1908 SmallVector<Expr *, 8> AllPlaceArgs;
1910 const FunctionProtoType *Proto =
1911 OperatorNew->getType()->getAs<FunctionProtoType>();
1912 VariadicCallType CallType = Proto->isVariadic() ? VariadicFunction
1913 : VariadicDoesNotApply;
1915 // We've already converted the placement args, just fill in any default
1916 // arguments. Skip the first parameter because we don't have a corresponding
1917 // argument. Skip the second parameter too if we're passing in the
1918 // alignment; we've already filled it in.
1919 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, Proto,
1920 PassAlignment ? 2 : 1, PlacementArgs,
1921 AllPlaceArgs, CallType))
1924 if (!AllPlaceArgs.empty())
1925 PlacementArgs = AllPlaceArgs;
1927 // FIXME: This is wrong: PlacementArgs misses out the first (size) argument.
1928 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, PlacementArgs);
1930 // FIXME: Missing call to CheckFunctionCall or equivalent
1932 // Warn if the type is over-aligned and is being allocated by (unaligned)
1933 // global operator new.
1934 if (PlacementArgs.empty() && !PassAlignment &&
1935 (OperatorNew->isImplicit() ||
1936 (OperatorNew->getLocStart().isValid() &&
1937 getSourceManager().isInSystemHeader(OperatorNew->getLocStart())))) {
1938 if (Alignment > NewAlignment)
1939 Diag(StartLoc, diag::warn_overaligned_type)
1941 << unsigned(Alignment / Context.getCharWidth())
1942 << unsigned(NewAlignment / Context.getCharWidth());
1946 // Array 'new' can't have any initializers except empty parentheses.
1947 // Initializer lists are also allowed, in C++11. Rely on the parser for the
1948 // dialect distinction.
1949 if (ArraySize && !isLegalArrayNewInitializer(initStyle, Initializer)) {
1950 SourceRange InitRange(Inits[0]->getLocStart(),
1951 Inits[NumInits - 1]->getLocEnd());
1952 Diag(StartLoc, diag::err_new_array_init_args) << InitRange;
1956 // If we can perform the initialization, and we've not already done so,
1958 if (!AllocType->isDependentType() &&
1959 !Expr::hasAnyTypeDependentArguments(
1960 llvm::makeArrayRef(Inits, NumInits))) {
1961 // The type we initialize is the complete type, including the array bound.
1964 InitType = Context.getConstantArrayType(
1965 AllocType, llvm::APInt(Context.getTypeSize(Context.getSizeType()),
1967 ArrayType::Normal, 0);
1970 Context.getIncompleteArrayType(AllocType, ArrayType::Normal, 0);
1972 InitType = AllocType;
1974 InitializedEntity Entity
1975 = InitializedEntity::InitializeNew(StartLoc, InitType);
1976 InitializationSequence InitSeq(*this, Entity, Kind,
1977 MultiExprArg(Inits, NumInits));
1978 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind,
1979 MultiExprArg(Inits, NumInits));
1980 if (FullInit.isInvalid())
1983 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because
1984 // we don't want the initialized object to be destructed.
1985 // FIXME: We should not create these in the first place.
1986 if (CXXBindTemporaryExpr *Binder =
1987 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get()))
1988 FullInit = Binder->getSubExpr();
1990 Initializer = FullInit.get();
1993 // Mark the new and delete operators as referenced.
1995 if (DiagnoseUseOfDecl(OperatorNew, StartLoc))
1997 MarkFunctionReferenced(StartLoc, OperatorNew);
1999 if (OperatorDelete) {
2000 if (DiagnoseUseOfDecl(OperatorDelete, StartLoc))
2002 MarkFunctionReferenced(StartLoc, OperatorDelete);
2005 // C++0x [expr.new]p17:
2006 // If the new expression creates an array of objects of class type,
2007 // access and ambiguity control are done for the destructor.
2008 QualType BaseAllocType = Context.getBaseElementType(AllocType);
2009 if (ArraySize && !BaseAllocType->isDependentType()) {
2010 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) {
2011 if (CXXDestructorDecl *dtor = LookupDestructor(
2012 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) {
2013 MarkFunctionReferenced(StartLoc, dtor);
2014 CheckDestructorAccess(StartLoc, dtor,
2015 PDiag(diag::err_access_dtor)
2017 if (DiagnoseUseOfDecl(dtor, StartLoc))
2023 return new (Context)
2024 CXXNewExpr(Context, UseGlobal, OperatorNew, OperatorDelete, PassAlignment,
2025 UsualArrayDeleteWantsSize, PlacementArgs, TypeIdParens,
2026 ArraySize, initStyle, Initializer, ResultType, AllocTypeInfo,
2027 Range, DirectInitRange);
2030 /// \brief Checks that a type is suitable as the allocated type
2031 /// in a new-expression.
2032 bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc,
2034 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
2035 // abstract class type or array thereof.
2036 if (AllocType->isFunctionType())
2037 return Diag(Loc, diag::err_bad_new_type)
2038 << AllocType << 0 << R;
2039 else if (AllocType->isReferenceType())
2040 return Diag(Loc, diag::err_bad_new_type)
2041 << AllocType << 1 << R;
2042 else if (!AllocType->isDependentType() &&
2043 RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R))
2045 else if (RequireNonAbstractType(Loc, AllocType,
2046 diag::err_allocation_of_abstract_type))
2048 else if (AllocType->isVariablyModifiedType())
2049 return Diag(Loc, diag::err_variably_modified_new_type)
2051 else if (AllocType.getAddressSpace())
2052 return Diag(Loc, diag::err_address_space_qualified_new)
2053 << AllocType.getUnqualifiedType()
2054 << AllocType.getQualifiers().getAddressSpaceAttributePrintValue();
2055 else if (getLangOpts().ObjCAutoRefCount) {
2056 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) {
2057 QualType BaseAllocType = Context.getBaseElementType(AT);
2058 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None &&
2059 BaseAllocType->isObjCLifetimeType())
2060 return Diag(Loc, diag::err_arc_new_array_without_ownership)
2069 resolveAllocationOverload(Sema &S, LookupResult &R, SourceRange Range,
2070 SmallVectorImpl<Expr *> &Args, bool &PassAlignment,
2071 FunctionDecl *&Operator,
2072 OverloadCandidateSet *AlignedCandidates = nullptr,
2073 Expr *AlignArg = nullptr) {
2074 OverloadCandidateSet Candidates(R.getNameLoc(),
2075 OverloadCandidateSet::CSK_Normal);
2076 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
2077 Alloc != AllocEnd; ++Alloc) {
2078 // Even member operator new/delete are implicitly treated as
2079 // static, so don't use AddMemberCandidate.
2080 NamedDecl *D = (*Alloc)->getUnderlyingDecl();
2082 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
2083 S.AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(),
2084 /*ExplicitTemplateArgs=*/nullptr, Args,
2086 /*SuppressUserConversions=*/false);
2090 FunctionDecl *Fn = cast<FunctionDecl>(D);
2091 S.AddOverloadCandidate(Fn, Alloc.getPair(), Args, Candidates,
2092 /*SuppressUserConversions=*/false);
2095 // Do the resolution.
2096 OverloadCandidateSet::iterator Best;
2097 switch (Candidates.BestViableFunction(S, R.getNameLoc(), Best)) {
2100 FunctionDecl *FnDecl = Best->Function;
2101 if (S.CheckAllocationAccess(R.getNameLoc(), Range, R.getNamingClass(),
2102 Best->FoundDecl) == Sema::AR_inaccessible)
2109 case OR_No_Viable_Function:
2110 // C++17 [expr.new]p13:
2111 // If no matching function is found and the allocated object type has
2112 // new-extended alignment, the alignment argument is removed from the
2113 // argument list, and overload resolution is performed again.
2114 if (PassAlignment) {
2115 PassAlignment = false;
2117 Args.erase(Args.begin() + 1);
2118 return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2119 Operator, &Candidates, AlignArg);
2122 // MSVC will fall back on trying to find a matching global operator new
2123 // if operator new[] cannot be found. Also, MSVC will leak by not
2124 // generating a call to operator delete or operator delete[], but we
2125 // will not replicate that bug.
2126 // FIXME: Find out how this interacts with the std::align_val_t fallback
2127 // once MSVC implements it.
2128 if (R.getLookupName().getCXXOverloadedOperator() == OO_Array_New &&
2129 S.Context.getLangOpts().MSVCCompat) {
2131 R.setLookupName(S.Context.DeclarationNames.getCXXOperatorName(OO_New));
2132 S.LookupQualifiedName(R, S.Context.getTranslationUnitDecl());
2133 // FIXME: This will give bad diagnostics pointing at the wrong functions.
2134 return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2138 S.Diag(R.getNameLoc(), diag::err_ovl_no_viable_function_in_call)
2139 << R.getLookupName() << Range;
2141 // If we have aligned candidates, only note the align_val_t candidates
2142 // from AlignedCandidates and the non-align_val_t candidates from
2144 if (AlignedCandidates) {
2145 auto IsAligned = [](OverloadCandidate &C) {
2146 return C.Function->getNumParams() > 1 &&
2147 C.Function->getParamDecl(1)->getType()->isAlignValT();
2149 auto IsUnaligned = [&](OverloadCandidate &C) { return !IsAligned(C); };
2151 // This was an overaligned allocation, so list the aligned candidates
2153 Args.insert(Args.begin() + 1, AlignArg);
2154 AlignedCandidates->NoteCandidates(S, OCD_AllCandidates, Args, "",
2155 R.getNameLoc(), IsAligned);
2156 Args.erase(Args.begin() + 1);
2157 Candidates.NoteCandidates(S, OCD_AllCandidates, Args, "", R.getNameLoc(),
2160 Candidates.NoteCandidates(S, OCD_AllCandidates, Args);
2165 S.Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call)
2166 << R.getLookupName() << Range;
2167 Candidates.NoteCandidates(S, OCD_ViableCandidates, Args);
2171 S.Diag(R.getNameLoc(), diag::err_ovl_deleted_call)
2172 << Best->Function->isDeleted()
2173 << R.getLookupName()
2174 << S.getDeletedOrUnavailableSuffix(Best->Function)
2176 Candidates.NoteCandidates(S, OCD_AllCandidates, Args);
2180 llvm_unreachable("Unreachable, bad result from BestViableFunction");
2184 /// FindAllocationFunctions - Finds the overloads of operator new and delete
2185 /// that are appropriate for the allocation.
2186 bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
2187 bool UseGlobal, QualType AllocType,
2188 bool IsArray, bool &PassAlignment,
2189 MultiExprArg PlaceArgs,
2190 FunctionDecl *&OperatorNew,
2191 FunctionDecl *&OperatorDelete) {
2192 // --- Choosing an allocation function ---
2193 // C++ 5.3.4p8 - 14 & 18
2194 // 1) If UseGlobal is true, only look in the global scope. Else, also look
2195 // in the scope of the allocated class.
2196 // 2) If an array size is given, look for operator new[], else look for
2198 // 3) The first argument is always size_t. Append the arguments from the
2201 SmallVector<Expr*, 8> AllocArgs;
2202 AllocArgs.reserve((PassAlignment ? 2 : 1) + PlaceArgs.size());
2204 // We don't care about the actual value of these arguments.
2205 // FIXME: Should the Sema create the expression and embed it in the syntax
2206 // tree? Or should the consumer just recalculate the value?
2207 // FIXME: Using a dummy value will interact poorly with attribute enable_if.
2208 IntegerLiteral Size(Context, llvm::APInt::getNullValue(
2209 Context.getTargetInfo().getPointerWidth(0)),
2210 Context.getSizeType(),
2212 AllocArgs.push_back(&Size);
2214 QualType AlignValT = Context.VoidTy;
2215 if (PassAlignment) {
2216 DeclareGlobalNewDelete();
2217 AlignValT = Context.getTypeDeclType(getStdAlignValT());
2219 CXXScalarValueInitExpr Align(AlignValT, nullptr, SourceLocation());
2221 AllocArgs.push_back(&Align);
2223 AllocArgs.insert(AllocArgs.end(), PlaceArgs.begin(), PlaceArgs.end());
2225 // C++ [expr.new]p8:
2226 // If the allocated type is a non-array type, the allocation
2227 // function's name is operator new and the deallocation function's
2228 // name is operator delete. If the allocated type is an array
2229 // type, the allocation function's name is operator new[] and the
2230 // deallocation function's name is operator delete[].
2231 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName(
2232 IsArray ? OO_Array_New : OO_New);
2234 QualType AllocElemType = Context.getBaseElementType(AllocType);
2236 // Find the allocation function.
2238 LookupResult R(*this, NewName, StartLoc, LookupOrdinaryName);
2240 // C++1z [expr.new]p9:
2241 // If the new-expression begins with a unary :: operator, the allocation
2242 // function's name is looked up in the global scope. Otherwise, if the
2243 // allocated type is a class type T or array thereof, the allocation
2244 // function's name is looked up in the scope of T.
2245 if (AllocElemType->isRecordType() && !UseGlobal)
2246 LookupQualifiedName(R, AllocElemType->getAsCXXRecordDecl());
2248 // We can see ambiguity here if the allocation function is found in
2249 // multiple base classes.
2250 if (R.isAmbiguous())
2253 // If this lookup fails to find the name, or if the allocated type is not
2254 // a class type, the allocation function's name is looked up in the
2257 LookupQualifiedName(R, Context.getTranslationUnitDecl());
2259 assert(!R.empty() && "implicitly declared allocation functions not found");
2260 assert(!R.isAmbiguous() && "global allocation functions are ambiguous");
2262 // We do our own custom access checks below.
2263 R.suppressDiagnostics();
2265 if (resolveAllocationOverload(*this, R, Range, AllocArgs, PassAlignment,
2270 // We don't need an operator delete if we're running under -fno-exceptions.
2271 if (!getLangOpts().Exceptions) {
2272 OperatorDelete = nullptr;
2276 // Note, the name of OperatorNew might have been changed from array to
2277 // non-array by resolveAllocationOverload.
2278 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
2279 OperatorNew->getDeclName().getCXXOverloadedOperator() == OO_Array_New
2283 // C++ [expr.new]p19:
2285 // If the new-expression begins with a unary :: operator, the
2286 // deallocation function's name is looked up in the global
2287 // scope. Otherwise, if the allocated type is a class type T or an
2288 // array thereof, the deallocation function's name is looked up in
2289 // the scope of T. If this lookup fails to find the name, or if
2290 // the allocated type is not a class type or array thereof, the
2291 // deallocation function's name is looked up in the global scope.
2292 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName);
2293 if (AllocElemType->isRecordType() && !UseGlobal) {
2295 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl());
2296 LookupQualifiedName(FoundDelete, RD);
2298 if (FoundDelete.isAmbiguous())
2299 return true; // FIXME: clean up expressions?
2301 bool FoundGlobalDelete = FoundDelete.empty();
2302 if (FoundDelete.empty()) {
2303 DeclareGlobalNewDelete();
2304 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2307 FoundDelete.suppressDiagnostics();
2309 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches;
2311 // Whether we're looking for a placement operator delete is dictated
2312 // by whether we selected a placement operator new, not by whether
2313 // we had explicit placement arguments. This matters for things like
2314 // struct A { void *operator new(size_t, int = 0); ... };
2317 // We don't have any definition for what a "placement allocation function"
2318 // is, but we assume it's any allocation function whose
2319 // parameter-declaration-clause is anything other than (size_t).
2321 // FIXME: Should (size_t, std::align_val_t) also be considered non-placement?
2322 // This affects whether an exception from the constructor of an overaligned
2323 // type uses the sized or non-sized form of aligned operator delete.
2324 bool isPlacementNew = !PlaceArgs.empty() || OperatorNew->param_size() != 1 ||
2325 OperatorNew->isVariadic();
2327 if (isPlacementNew) {
2328 // C++ [expr.new]p20:
2329 // A declaration of a placement deallocation function matches the
2330 // declaration of a placement allocation function if it has the
2331 // same number of parameters and, after parameter transformations
2332 // (8.3.5), all parameter types except the first are
2335 // To perform this comparison, we compute the function type that
2336 // the deallocation function should have, and use that type both
2337 // for template argument deduction and for comparison purposes.
2338 QualType ExpectedFunctionType;
2340 const FunctionProtoType *Proto
2341 = OperatorNew->getType()->getAs<FunctionProtoType>();
2343 SmallVector<QualType, 4> ArgTypes;
2344 ArgTypes.push_back(Context.VoidPtrTy);
2345 for (unsigned I = 1, N = Proto->getNumParams(); I < N; ++I)
2346 ArgTypes.push_back(Proto->getParamType(I));
2348 FunctionProtoType::ExtProtoInfo EPI;
2349 // FIXME: This is not part of the standard's rule.
2350 EPI.Variadic = Proto->isVariadic();
2352 ExpectedFunctionType
2353 = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI);
2356 for (LookupResult::iterator D = FoundDelete.begin(),
2357 DEnd = FoundDelete.end();
2359 FunctionDecl *Fn = nullptr;
2360 if (FunctionTemplateDecl *FnTmpl =
2361 dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) {
2362 // Perform template argument deduction to try to match the
2363 // expected function type.
2364 TemplateDeductionInfo Info(StartLoc);
2365 if (DeduceTemplateArguments(FnTmpl, nullptr, ExpectedFunctionType, Fn,
2369 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl());
2371 if (Context.hasSameType(adjustCCAndNoReturn(Fn->getType(),
2372 ExpectedFunctionType,
2373 /*AdjustExcpetionSpec*/true),
2374 ExpectedFunctionType))
2375 Matches.push_back(std::make_pair(D.getPair(), Fn));
2378 if (getLangOpts().CUDA)
2379 EraseUnwantedCUDAMatches(dyn_cast<FunctionDecl>(CurContext), Matches);
2381 // C++1y [expr.new]p22:
2382 // For a non-placement allocation function, the normal deallocation
2383 // function lookup is used
2385 // Per [expr.delete]p10, this lookup prefers a member operator delete
2386 // without a size_t argument, but prefers a non-member operator delete
2387 // with a size_t where possible (which it always is in this case).
2388 llvm::SmallVector<UsualDeallocFnInfo, 4> BestDeallocFns;
2389 UsualDeallocFnInfo Selected = resolveDeallocationOverload(
2390 *this, FoundDelete, /*WantSize*/ FoundGlobalDelete,
2391 /*WantAlign*/ hasNewExtendedAlignment(*this, AllocElemType),
2394 Matches.push_back(std::make_pair(Selected.Found, Selected.FD));
2396 // If we failed to select an operator, all remaining functions are viable
2398 for (auto Fn : BestDeallocFns)
2399 Matches.push_back(std::make_pair(Fn.Found, Fn.FD));
2403 // C++ [expr.new]p20:
2404 // [...] If the lookup finds a single matching deallocation
2405 // function, that function will be called; otherwise, no
2406 // deallocation function will be called.
2407 if (Matches.size() == 1) {
2408 OperatorDelete = Matches[0].second;
2410 // C++1z [expr.new]p23:
2411 // If the lookup finds a usual deallocation function (3.7.4.2)
2412 // with a parameter of type std::size_t and that function, considered
2413 // as a placement deallocation function, would have been
2414 // selected as a match for the allocation function, the program
2416 if (getLangOpts().CPlusPlus11 && isPlacementNew &&
2417 isNonPlacementDeallocationFunction(*this, OperatorDelete)) {
2418 UsualDeallocFnInfo Info(*this,
2419 DeclAccessPair::make(OperatorDelete, AS_public));
2420 // Core issue, per mail to core reflector, 2016-10-09:
2421 // If this is a member operator delete, and there is a corresponding
2422 // non-sized member operator delete, this isn't /really/ a sized
2423 // deallocation function, it just happens to have a size_t parameter.
2424 bool IsSizedDelete = Info.HasSizeT;
2425 if (IsSizedDelete && !FoundGlobalDelete) {
2426 auto NonSizedDelete =
2427 resolveDeallocationOverload(*this, FoundDelete, /*WantSize*/false,
2428 /*WantAlign*/Info.HasAlignValT);
2429 if (NonSizedDelete && !NonSizedDelete.HasSizeT &&
2430 NonSizedDelete.HasAlignValT == Info.HasAlignValT)
2431 IsSizedDelete = false;
2434 if (IsSizedDelete) {
2435 SourceRange R = PlaceArgs.empty()
2437 : SourceRange(PlaceArgs.front()->getLocStart(),
2438 PlaceArgs.back()->getLocEnd());
2439 Diag(StartLoc, diag::err_placement_new_non_placement_delete) << R;
2440 if (!OperatorDelete->isImplicit())
2441 Diag(OperatorDelete->getLocation(), diag::note_previous_decl)
2446 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(),
2448 } else if (!Matches.empty()) {
2449 // We found multiple suitable operators. Per [expr.new]p20, that means we
2450 // call no 'operator delete' function, but we should at least warn the user.
2451 // FIXME: Suppress this warning if the construction cannot throw.
2452 Diag(StartLoc, diag::warn_ambiguous_suitable_delete_function_found)
2453 << DeleteName << AllocElemType;
2455 for (auto &Match : Matches)
2456 Diag(Match.second->getLocation(),
2457 diag::note_member_declared_here) << DeleteName;
2463 /// DeclareGlobalNewDelete - Declare the global forms of operator new and
2464 /// delete. These are:
2467 /// void* operator new(std::size_t) throw(std::bad_alloc);
2468 /// void* operator new[](std::size_t) throw(std::bad_alloc);
2469 /// void operator delete(void *) throw();
2470 /// void operator delete[](void *) throw();
2472 /// void* operator new(std::size_t);
2473 /// void* operator new[](std::size_t);
2474 /// void operator delete(void *) noexcept;
2475 /// void operator delete[](void *) noexcept;
2477 /// void* operator new(std::size_t);
2478 /// void* operator new[](std::size_t);
2479 /// void operator delete(void *) noexcept;
2480 /// void operator delete[](void *) noexcept;
2481 /// void operator delete(void *, std::size_t) noexcept;
2482 /// void operator delete[](void *, std::size_t) noexcept;
2484 /// Note that the placement and nothrow forms of new are *not* implicitly
2485 /// declared. Their use requires including \<new\>.
2486 void Sema::DeclareGlobalNewDelete() {
2487 if (GlobalNewDeleteDeclared)
2490 // C++ [basic.std.dynamic]p2:
2491 // [...] The following allocation and deallocation functions (18.4) are
2492 // implicitly declared in global scope in each translation unit of a
2496 // void* operator new(std::size_t) throw(std::bad_alloc);
2497 // void* operator new[](std::size_t) throw(std::bad_alloc);
2498 // void operator delete(void*) throw();
2499 // void operator delete[](void*) throw();
2501 // void* operator new(std::size_t);
2502 // void* operator new[](std::size_t);
2503 // void operator delete(void*) noexcept;
2504 // void operator delete[](void*) noexcept;
2506 // void* operator new(std::size_t);
2507 // void* operator new[](std::size_t);
2508 // void operator delete(void*) noexcept;
2509 // void operator delete[](void*) noexcept;
2510 // void operator delete(void*, std::size_t) noexcept;
2511 // void operator delete[](void*, std::size_t) noexcept;
2513 // These implicit declarations introduce only the function names operator
2514 // new, operator new[], operator delete, operator delete[].
2516 // Here, we need to refer to std::bad_alloc, so we will implicitly declare
2517 // "std" or "bad_alloc" as necessary to form the exception specification.
2518 // However, we do not make these implicit declarations visible to name
2520 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) {
2521 // The "std::bad_alloc" class has not yet been declared, so build it
2523 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class,
2524 getOrCreateStdNamespace(),
2525 SourceLocation(), SourceLocation(),
2526 &PP.getIdentifierTable().get("bad_alloc"),
2528 getStdBadAlloc()->setImplicit(true);
2530 if (!StdAlignValT && getLangOpts().AlignedAllocation) {
2531 // The "std::align_val_t" enum class has not yet been declared, so build it
2533 auto *AlignValT = EnumDecl::Create(
2534 Context, getOrCreateStdNamespace(), SourceLocation(), SourceLocation(),
2535 &PP.getIdentifierTable().get("align_val_t"), nullptr, true, true, true);
2536 AlignValT->setIntegerType(Context.getSizeType());
2537 AlignValT->setPromotionType(Context.getSizeType());
2538 AlignValT->setImplicit(true);
2539 StdAlignValT = AlignValT;
2542 GlobalNewDeleteDeclared = true;
2544 QualType VoidPtr = Context.getPointerType(Context.VoidTy);
2545 QualType SizeT = Context.getSizeType();
2547 auto DeclareGlobalAllocationFunctions = [&](OverloadedOperatorKind Kind,
2548 QualType Return, QualType Param) {
2549 llvm::SmallVector<QualType, 3> Params;
2550 Params.push_back(Param);
2552 // Create up to four variants of the function (sized/aligned).
2553 bool HasSizedVariant = getLangOpts().SizedDeallocation &&
2554 (Kind == OO_Delete || Kind == OO_Array_Delete);
2555 bool HasAlignedVariant = getLangOpts().AlignedAllocation;
2557 int NumSizeVariants = (HasSizedVariant ? 2 : 1);
2558 int NumAlignVariants = (HasAlignedVariant ? 2 : 1);
2559 for (int Sized = 0; Sized < NumSizeVariants; ++Sized) {
2561 Params.push_back(SizeT);
2563 for (int Aligned = 0; Aligned < NumAlignVariants; ++Aligned) {
2565 Params.push_back(Context.getTypeDeclType(getStdAlignValT()));
2567 DeclareGlobalAllocationFunction(
2568 Context.DeclarationNames.getCXXOperatorName(Kind), Return, Params);
2576 DeclareGlobalAllocationFunctions(OO_New, VoidPtr, SizeT);
2577 DeclareGlobalAllocationFunctions(OO_Array_New, VoidPtr, SizeT);
2578 DeclareGlobalAllocationFunctions(OO_Delete, Context.VoidTy, VoidPtr);
2579 DeclareGlobalAllocationFunctions(OO_Array_Delete, Context.VoidTy, VoidPtr);
2582 /// DeclareGlobalAllocationFunction - Declares a single implicit global
2583 /// allocation function if it doesn't already exist.
2584 void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
2586 ArrayRef<QualType> Params) {
2587 DeclContext *GlobalCtx = Context.getTranslationUnitDecl();
2589 // Check if this function is already declared.
2590 DeclContext::lookup_result R = GlobalCtx->lookup(Name);
2591 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end();
2592 Alloc != AllocEnd; ++Alloc) {
2593 // Only look at non-template functions, as it is the predefined,
2594 // non-templated allocation function we are trying to declare here.
2595 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
2596 if (Func->getNumParams() == Params.size()) {
2597 llvm::SmallVector<QualType, 3> FuncParams;
2598 for (auto *P : Func->parameters())
2599 FuncParams.push_back(
2600 Context.getCanonicalType(P->getType().getUnqualifiedType()));
2601 if (llvm::makeArrayRef(FuncParams) == Params) {
2602 // Make the function visible to name lookup, even if we found it in
2603 // an unimported module. It either is an implicitly-declared global
2604 // allocation function, or is suppressing that function.
2605 Func->setHidden(false);
2612 FunctionProtoType::ExtProtoInfo EPI;
2614 QualType BadAllocType;
2615 bool HasBadAllocExceptionSpec
2616 = (Name.getCXXOverloadedOperator() == OO_New ||
2617 Name.getCXXOverloadedOperator() == OO_Array_New);
2618 if (HasBadAllocExceptionSpec) {
2619 if (!getLangOpts().CPlusPlus11) {
2620 BadAllocType = Context.getTypeDeclType(getStdBadAlloc());
2621 assert(StdBadAlloc && "Must have std::bad_alloc declared");
2622 EPI.ExceptionSpec.Type = EST_Dynamic;
2623 EPI.ExceptionSpec.Exceptions = llvm::makeArrayRef(BadAllocType);
2627 getLangOpts().CPlusPlus11 ? EST_BasicNoexcept : EST_DynamicNone;
2630 auto CreateAllocationFunctionDecl = [&](Attr *ExtraAttr) {
2631 QualType FnType = Context.getFunctionType(Return, Params, EPI);
2632 FunctionDecl *Alloc = FunctionDecl::Create(
2633 Context, GlobalCtx, SourceLocation(), SourceLocation(), Name,
2634 FnType, /*TInfo=*/nullptr, SC_None, false, true);
2635 Alloc->setImplicit();
2637 // Implicit sized deallocation functions always have default visibility.
2639 VisibilityAttr::CreateImplicit(Context, VisibilityAttr::Default));
2641 llvm::SmallVector<ParmVarDecl *, 3> ParamDecls;
2642 for (QualType T : Params) {
2643 ParamDecls.push_back(ParmVarDecl::Create(
2644 Context, Alloc, SourceLocation(), SourceLocation(), nullptr, T,
2645 /*TInfo=*/nullptr, SC_None, nullptr));
2646 ParamDecls.back()->setImplicit();
2648 Alloc->setParams(ParamDecls);
2650 Alloc->addAttr(ExtraAttr);
2651 Context.getTranslationUnitDecl()->addDecl(Alloc);
2652 IdResolver.tryAddTopLevelDecl(Alloc, Name);
2656 CreateAllocationFunctionDecl(nullptr);
2658 // Host and device get their own declaration so each can be
2659 // defined or re-declared independently.
2660 CreateAllocationFunctionDecl(CUDAHostAttr::CreateImplicit(Context));
2661 CreateAllocationFunctionDecl(CUDADeviceAttr::CreateImplicit(Context));
2665 FunctionDecl *Sema::FindUsualDeallocationFunction(SourceLocation StartLoc,
2666 bool CanProvideSize,
2668 DeclarationName Name) {
2669 DeclareGlobalNewDelete();
2671 LookupResult FoundDelete(*this, Name, StartLoc, LookupOrdinaryName);
2672 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2674 // FIXME: It's possible for this to result in ambiguity, through a
2675 // user-declared variadic operator delete or the enable_if attribute. We
2676 // should probably not consider those cases to be usual deallocation
2677 // functions. But for now we just make an arbitrary choice in that case.
2678 auto Result = resolveDeallocationOverload(*this, FoundDelete, CanProvideSize,
2680 assert(Result.FD && "operator delete missing from global scope?");
2684 FunctionDecl *Sema::FindDeallocationFunctionForDestructor(SourceLocation Loc,
2685 CXXRecordDecl *RD) {
2686 DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Delete);
2688 FunctionDecl *OperatorDelete = nullptr;
2689 if (FindDeallocationFunction(Loc, RD, Name, OperatorDelete))
2692 return OperatorDelete;
2694 // If there's no class-specific operator delete, look up the global
2695 // non-array delete.
2696 return FindUsualDeallocationFunction(
2697 Loc, true, hasNewExtendedAlignment(*this, Context.getRecordType(RD)),
2701 bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
2702 DeclarationName Name,
2703 FunctionDecl *&Operator, bool Diagnose) {
2704 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
2705 // Try to find operator delete/operator delete[] in class scope.
2706 LookupQualifiedName(Found, RD);
2708 if (Found.isAmbiguous())
2711 Found.suppressDiagnostics();
2713 bool Overaligned = hasNewExtendedAlignment(*this, Context.getRecordType(RD));
2715 // C++17 [expr.delete]p10:
2716 // If the deallocation functions have class scope, the one without a
2717 // parameter of type std::size_t is selected.
2718 llvm::SmallVector<UsualDeallocFnInfo, 4> Matches;
2719 resolveDeallocationOverload(*this, Found, /*WantSize*/ false,
2720 /*WantAlign*/ Overaligned, &Matches);
2722 // If we could find an overload, use it.
2723 if (Matches.size() == 1) {
2724 Operator = cast<CXXMethodDecl>(Matches[0].FD);
2726 // FIXME: DiagnoseUseOfDecl?
2727 if (Operator->isDeleted()) {
2729 Diag(StartLoc, diag::err_deleted_function_use);
2730 NoteDeletedFunction(Operator);
2735 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(),
2736 Matches[0].Found, Diagnose) == AR_inaccessible)
2742 // We found multiple suitable operators; complain about the ambiguity.
2743 // FIXME: The standard doesn't say to do this; it appears that the intent
2744 // is that this should never happen.
2745 if (!Matches.empty()) {
2747 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found)
2749 for (auto &Match : Matches)
2750 Diag(Match.FD->getLocation(), diag::note_member_declared_here) << Name;
2755 // We did find operator delete/operator delete[] declarations, but
2756 // none of them were suitable.
2757 if (!Found.empty()) {
2759 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found)
2762 for (NamedDecl *D : Found)
2763 Diag(D->getUnderlyingDecl()->getLocation(),
2764 diag::note_member_declared_here) << Name;
2774 /// \brief Checks whether delete-expression, and new-expression used for
2775 /// initializing deletee have the same array form.
2776 class MismatchingNewDeleteDetector {
2778 enum MismatchResult {
2779 /// Indicates that there is no mismatch or a mismatch cannot be proven.
2781 /// Indicates that variable is initialized with mismatching form of \a new.
2783 /// Indicates that member is initialized with mismatching form of \a new.
2784 MemberInitMismatches,
2785 /// Indicates that 1 or more constructors' definitions could not been
2786 /// analyzed, and they will be checked again at the end of translation unit.
2790 /// \param EndOfTU True, if this is the final analysis at the end of
2791 /// translation unit. False, if this is the initial analysis at the point
2792 /// delete-expression was encountered.
2793 explicit MismatchingNewDeleteDetector(bool EndOfTU)
2794 : Field(nullptr), IsArrayForm(false), EndOfTU(EndOfTU),
2795 HasUndefinedConstructors(false) {}
2797 /// \brief Checks whether pointee of a delete-expression is initialized with
2798 /// matching form of new-expression.
2800 /// If return value is \c VarInitMismatches or \c MemberInitMismatches at the
2801 /// point where delete-expression is encountered, then a warning will be
2802 /// issued immediately. If return value is \c AnalyzeLater at the point where
2803 /// delete-expression is seen, then member will be analyzed at the end of
2804 /// translation unit. \c AnalyzeLater is returned iff at least one constructor
2805 /// couldn't be analyzed. If at least one constructor initializes the member
2806 /// with matching type of new, the return value is \c NoMismatch.
2807 MismatchResult analyzeDeleteExpr(const CXXDeleteExpr *DE);
2808 /// \brief Analyzes a class member.
2809 /// \param Field Class member to analyze.
2810 /// \param DeleteWasArrayForm Array form-ness of the delete-expression used
2811 /// for deleting the \p Field.
2812 MismatchResult analyzeField(FieldDecl *Field, bool DeleteWasArrayForm);
2814 /// List of mismatching new-expressions used for initialization of the pointee
2815 llvm::SmallVector<const CXXNewExpr *, 4> NewExprs;
2816 /// Indicates whether delete-expression was in array form.
2821 /// \brief Indicates that there is at least one constructor without body.
2822 bool HasUndefinedConstructors;
2823 /// \brief Returns \c CXXNewExpr from given initialization expression.
2824 /// \param E Expression used for initializing pointee in delete-expression.
2825 /// E can be a single-element \c InitListExpr consisting of new-expression.
2826 const CXXNewExpr *getNewExprFromInitListOrExpr(const Expr *E);
2827 /// \brief Returns whether member is initialized with mismatching form of
2828 /// \c new either by the member initializer or in-class initialization.
2830 /// If bodies of all constructors are not visible at the end of translation
2831 /// unit or at least one constructor initializes member with the matching
2832 /// form of \c new, mismatch cannot be proven, and this function will return
2834 MismatchResult analyzeMemberExpr(const MemberExpr *ME);
2835 /// \brief Returns whether variable is initialized with mismatching form of
2838 /// If variable is initialized with matching form of \c new or variable is not
2839 /// initialized with a \c new expression, this function will return true.
2840 /// If variable is initialized with mismatching form of \c new, returns false.
2841 /// \param D Variable to analyze.
2842 bool hasMatchingVarInit(const DeclRefExpr *D);
2843 /// \brief Checks whether the constructor initializes pointee with mismatching
2846 /// Returns true, if member is initialized with matching form of \c new in
2847 /// member initializer list. Returns false, if member is initialized with the
2848 /// matching form of \c new in this constructor's initializer or given
2849 /// constructor isn't defined at the point where delete-expression is seen, or
2850 /// member isn't initialized by the constructor.
2851 bool hasMatchingNewInCtor(const CXXConstructorDecl *CD);
2852 /// \brief Checks whether member is initialized with matching form of
2853 /// \c new in member initializer list.
2854 bool hasMatchingNewInCtorInit(const CXXCtorInitializer *CI);
2855 /// Checks whether member is initialized with mismatching form of \c new by
2856 /// in-class initializer.
2857 MismatchResult analyzeInClassInitializer();
2861 MismatchingNewDeleteDetector::MismatchResult
2862 MismatchingNewDeleteDetector::analyzeDeleteExpr(const CXXDeleteExpr *DE) {
2864 assert(DE && "Expected delete-expression");
2865 IsArrayForm = DE->isArrayForm();
2866 const Expr *E = DE->getArgument()->IgnoreParenImpCasts();
2867 if (const MemberExpr *ME = dyn_cast<const MemberExpr>(E)) {
2868 return analyzeMemberExpr(ME);
2869 } else if (const DeclRefExpr *D = dyn_cast<const DeclRefExpr>(E)) {
2870 if (!hasMatchingVarInit(D))
2871 return VarInitMismatches;
2877 MismatchingNewDeleteDetector::getNewExprFromInitListOrExpr(const Expr *E) {
2878 assert(E != nullptr && "Expected a valid initializer expression");
2879 E = E->IgnoreParenImpCasts();
2880 if (const InitListExpr *ILE = dyn_cast<const InitListExpr>(E)) {
2881 if (ILE->getNumInits() == 1)
2882 E = dyn_cast<const CXXNewExpr>(ILE->getInit(0)->IgnoreParenImpCasts());
2885 return dyn_cast_or_null<const CXXNewExpr>(E);
2888 bool MismatchingNewDeleteDetector::hasMatchingNewInCtorInit(
2889 const CXXCtorInitializer *CI) {
2890 const CXXNewExpr *NE = nullptr;
2891 if (Field == CI->getMember() &&
2892 (NE = getNewExprFromInitListOrExpr(CI->getInit()))) {
2893 if (NE->isArray() == IsArrayForm)
2896 NewExprs.push_back(NE);
2901 bool MismatchingNewDeleteDetector::hasMatchingNewInCtor(
2902 const CXXConstructorDecl *CD) {
2903 if (CD->isImplicit())
2905 const FunctionDecl *Definition = CD;
2906 if (!CD->isThisDeclarationADefinition() && !CD->isDefined(Definition)) {
2907 HasUndefinedConstructors = true;
2910 for (const auto *CI : cast<const CXXConstructorDecl>(Definition)->inits()) {
2911 if (hasMatchingNewInCtorInit(CI))
2917 MismatchingNewDeleteDetector::MismatchResult
2918 MismatchingNewDeleteDetector::analyzeInClassInitializer() {
2919 assert(Field != nullptr && "This should be called only for members");
2920 const Expr *InitExpr = Field->getInClassInitializer();
2922 return EndOfTU ? NoMismatch : AnalyzeLater;
2923 if (const CXXNewExpr *NE = getNewExprFromInitListOrExpr(InitExpr)) {
2924 if (NE->isArray() != IsArrayForm) {
2925 NewExprs.push_back(NE);
2926 return MemberInitMismatches;
2932 MismatchingNewDeleteDetector::MismatchResult
2933 MismatchingNewDeleteDetector::analyzeField(FieldDecl *Field,
2934 bool DeleteWasArrayForm) {
2935 assert(Field != nullptr && "Analysis requires a valid class member.");
2936 this->Field = Field;
2937 IsArrayForm = DeleteWasArrayForm;
2938 const CXXRecordDecl *RD = cast<const CXXRecordDecl>(Field->getParent());
2939 for (const auto *CD : RD->ctors()) {
2940 if (hasMatchingNewInCtor(CD))
2943 if (HasUndefinedConstructors)
2944 return EndOfTU ? NoMismatch : AnalyzeLater;
2945 if (!NewExprs.empty())
2946 return MemberInitMismatches;
2947 return Field->hasInClassInitializer() ? analyzeInClassInitializer()
2951 MismatchingNewDeleteDetector::MismatchResult
2952 MismatchingNewDeleteDetector::analyzeMemberExpr(const MemberExpr *ME) {
2953 assert(ME != nullptr && "Expected a member expression");
2954 if (FieldDecl *F = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2955 return analyzeField(F, IsArrayForm);
2959 bool MismatchingNewDeleteDetector::hasMatchingVarInit(const DeclRefExpr *D) {
2960 const CXXNewExpr *NE = nullptr;
2961 if (const VarDecl *VD = dyn_cast<const VarDecl>(D->getDecl())) {
2962 if (VD->hasInit() && (NE = getNewExprFromInitListOrExpr(VD->getInit())) &&
2963 NE->isArray() != IsArrayForm) {
2964 NewExprs.push_back(NE);
2967 return NewExprs.empty();
2971 DiagnoseMismatchedNewDelete(Sema &SemaRef, SourceLocation DeleteLoc,
2972 const MismatchingNewDeleteDetector &Detector) {
2973 SourceLocation EndOfDelete = SemaRef.getLocForEndOfToken(DeleteLoc);
2975 if (!Detector.IsArrayForm)
2976 H = FixItHint::CreateInsertion(EndOfDelete, "[]");
2978 SourceLocation RSquare = Lexer::findLocationAfterToken(
2979 DeleteLoc, tok::l_square, SemaRef.getSourceManager(),
2980 SemaRef.getLangOpts(), true);
2981 if (RSquare.isValid())
2982 H = FixItHint::CreateRemoval(SourceRange(EndOfDelete, RSquare));
2984 SemaRef.Diag(DeleteLoc, diag::warn_mismatched_delete_new)
2985 << Detector.IsArrayForm << H;
2987 for (const auto *NE : Detector.NewExprs)
2988 SemaRef.Diag(NE->getExprLoc(), diag::note_allocated_here)
2989 << Detector.IsArrayForm;
2992 void Sema::AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE) {
2993 if (Diags.isIgnored(diag::warn_mismatched_delete_new, SourceLocation()))
2995 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/false);
2996 switch (Detector.analyzeDeleteExpr(DE)) {
2997 case MismatchingNewDeleteDetector::VarInitMismatches:
2998 case MismatchingNewDeleteDetector::MemberInitMismatches: {
2999 DiagnoseMismatchedNewDelete(*this, DE->getLocStart(), Detector);
3002 case MismatchingNewDeleteDetector::AnalyzeLater: {
3003 DeleteExprs[Detector.Field].push_back(
3004 std::make_pair(DE->getLocStart(), DE->isArrayForm()));
3007 case MismatchingNewDeleteDetector::NoMismatch:
3012 void Sema::AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
3013 bool DeleteWasArrayForm) {
3014 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/true);
3015 switch (Detector.analyzeField(Field, DeleteWasArrayForm)) {
3016 case MismatchingNewDeleteDetector::VarInitMismatches:
3017 llvm_unreachable("This analysis should have been done for class members.");
3018 case MismatchingNewDeleteDetector::AnalyzeLater:
3019 llvm_unreachable("Analysis cannot be postponed any point beyond end of "
3020 "translation unit.");
3021 case MismatchingNewDeleteDetector::MemberInitMismatches:
3022 DiagnoseMismatchedNewDelete(*this, DeleteLoc, Detector);
3024 case MismatchingNewDeleteDetector::NoMismatch:
3029 /// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in:
3030 /// @code ::delete ptr; @endcode
3032 /// @code delete [] ptr; @endcode
3034 Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
3035 bool ArrayForm, Expr *ExE) {
3036 // C++ [expr.delete]p1:
3037 // The operand shall have a pointer type, or a class type having a single
3038 // non-explicit conversion function to a pointer type. The result has type
3041 // DR599 amends "pointer type" to "pointer to object type" in both cases.
3043 ExprResult Ex = ExE;
3044 FunctionDecl *OperatorDelete = nullptr;
3045 bool ArrayFormAsWritten = ArrayForm;
3046 bool UsualArrayDeleteWantsSize = false;
3048 if (!Ex.get()->isTypeDependent()) {
3049 // Perform lvalue-to-rvalue cast, if needed.
3050 Ex = DefaultLvalueConversion(Ex.get());
3054 QualType Type = Ex.get()->getType();
3056 class DeleteConverter : public ContextualImplicitConverter {
3058 DeleteConverter() : ContextualImplicitConverter(false, true) {}
3060 bool match(QualType ConvType) override {
3061 // FIXME: If we have an operator T* and an operator void*, we must pick
3063 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
3064 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType())
3069 SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
3070 QualType T) override {
3071 return S.Diag(Loc, diag::err_delete_operand) << T;
3074 SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
3075 QualType T) override {
3076 return S.Diag(Loc, diag::err_delete_incomplete_class_type) << T;
3079 SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
3081 QualType ConvTy) override {
3082 return S.Diag(Loc, diag::err_delete_explicit_conversion) << T << ConvTy;
3085 SemaDiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
3086 QualType ConvTy) override {
3087 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3091 SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
3092 QualType T) override {
3093 return S.Diag(Loc, diag::err_ambiguous_delete_operand) << T;
3096 SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
3097 QualType ConvTy) override {
3098 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3102 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
3104 QualType ConvTy) override {
3105 llvm_unreachable("conversion functions are permitted");
3109 Ex = PerformContextualImplicitConversion(StartLoc, Ex.get(), Converter);
3112 Type = Ex.get()->getType();
3113 if (!Converter.match(Type))
3114 // FIXME: PerformContextualImplicitConversion should return ExprError
3115 // itself in this case.
3118 QualType Pointee = Type->getAs<PointerType>()->getPointeeType();
3119 QualType PointeeElem = Context.getBaseElementType(Pointee);
3121 if (Pointee.getAddressSpace())
3122 return Diag(Ex.get()->getLocStart(),
3123 diag::err_address_space_qualified_delete)
3124 << Pointee.getUnqualifiedType()
3125 << Pointee.getQualifiers().getAddressSpaceAttributePrintValue();
3127 CXXRecordDecl *PointeeRD = nullptr;
3128 if (Pointee->isVoidType() && !isSFINAEContext()) {
3129 // The C++ standard bans deleting a pointer to a non-object type, which
3130 // effectively bans deletion of "void*". However, most compilers support
3131 // this, so we treat it as a warning unless we're in a SFINAE context.
3132 Diag(StartLoc, diag::ext_delete_void_ptr_operand)
3133 << Type << Ex.get()->getSourceRange();
3134 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) {
3135 return ExprError(Diag(StartLoc, diag::err_delete_operand)
3136 << Type << Ex.get()->getSourceRange());
3137 } else if (!Pointee->isDependentType()) {
3138 // FIXME: This can result in errors if the definition was imported from a
3139 // module but is hidden.
3140 if (!RequireCompleteType(StartLoc, Pointee,
3141 diag::warn_delete_incomplete, Ex.get())) {
3142 if (const RecordType *RT = PointeeElem->getAs<RecordType>())
3143 PointeeRD = cast<CXXRecordDecl>(RT->getDecl());
3147 if (Pointee->isArrayType() && !ArrayForm) {
3148 Diag(StartLoc, diag::warn_delete_array_type)
3149 << Type << Ex.get()->getSourceRange()
3150 << FixItHint::CreateInsertion(getLocForEndOfToken(StartLoc), "[]");
3154 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
3155 ArrayForm ? OO_Array_Delete : OO_Delete);
3159 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName,
3163 // If we're allocating an array of records, check whether the
3164 // usual operator delete[] has a size_t parameter.
3166 // If the user specifically asked to use the global allocator,
3167 // we'll need to do the lookup into the class.
3169 UsualArrayDeleteWantsSize =
3170 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem);
3172 // Otherwise, the usual operator delete[] should be the
3173 // function we just found.
3174 else if (OperatorDelete && isa<CXXMethodDecl>(OperatorDelete))
3175 UsualArrayDeleteWantsSize =
3176 UsualDeallocFnInfo(*this,
3177 DeclAccessPair::make(OperatorDelete, AS_public))
3181 if (!PointeeRD->hasIrrelevantDestructor())
3182 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3183 MarkFunctionReferenced(StartLoc,
3184 const_cast<CXXDestructorDecl*>(Dtor));
3185 if (DiagnoseUseOfDecl(Dtor, StartLoc))
3189 CheckVirtualDtorCall(PointeeRD->getDestructor(), StartLoc,
3190 /*IsDelete=*/true, /*CallCanBeVirtual=*/true,
3191 /*WarnOnNonAbstractTypes=*/!ArrayForm,
3195 if (!OperatorDelete) {
3196 bool IsComplete = isCompleteType(StartLoc, Pointee);
3197 bool CanProvideSize =
3198 IsComplete && (!ArrayForm || UsualArrayDeleteWantsSize ||
3199 Pointee.isDestructedType());
3200 bool Overaligned = hasNewExtendedAlignment(*this, Pointee);
3202 // Look for a global declaration.
3203 OperatorDelete = FindUsualDeallocationFunction(StartLoc, CanProvideSize,
3204 Overaligned, DeleteName);
3207 MarkFunctionReferenced(StartLoc, OperatorDelete);
3209 // Check access and ambiguity of operator delete and destructor.
3211 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3212 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor,
3213 PDiag(diag::err_access_dtor) << PointeeElem);
3218 CXXDeleteExpr *Result = new (Context) CXXDeleteExpr(
3219 Context.VoidTy, UseGlobal, ArrayForm, ArrayFormAsWritten,
3220 UsualArrayDeleteWantsSize, OperatorDelete, Ex.get(), StartLoc);
3221 AnalyzeDeleteExprMismatch(Result);
3225 void Sema::CheckVirtualDtorCall(CXXDestructorDecl *dtor, SourceLocation Loc,
3226 bool IsDelete, bool CallCanBeVirtual,
3227 bool WarnOnNonAbstractTypes,
3228 SourceLocation DtorLoc) {
3229 if (!dtor || dtor->isVirtual() || !CallCanBeVirtual)
3232 // C++ [expr.delete]p3:
3233 // In the first alternative (delete object), if the static type of the
3234 // object to be deleted is different from its dynamic type, the static
3235 // type shall be a base class of the dynamic type of the object to be
3236 // deleted and the static type shall have a virtual destructor or the
3237 // behavior is undefined.
3239 const CXXRecordDecl *PointeeRD = dtor->getParent();
3240 // Note: a final class cannot be derived from, no issue there
3241 if (!PointeeRD->isPolymorphic() || PointeeRD->hasAttr<FinalAttr>())
3244 QualType ClassType = dtor->getThisType(Context)->getPointeeType();
3245 if (PointeeRD->isAbstract()) {
3246 // If the class is abstract, we warn by default, because we're
3247 // sure the code has undefined behavior.
3248 Diag(Loc, diag::warn_delete_abstract_non_virtual_dtor) << (IsDelete ? 0 : 1)
3250 } else if (WarnOnNonAbstractTypes) {
3251 // Otherwise, if this is not an array delete, it's a bit suspect,
3252 // but not necessarily wrong.
3253 Diag(Loc, diag::warn_delete_non_virtual_dtor) << (IsDelete ? 0 : 1)
3257 std::string TypeStr;
3258 ClassType.getAsStringInternal(TypeStr, getPrintingPolicy());
3259 Diag(DtorLoc, diag::note_delete_non_virtual)
3260 << FixItHint::CreateInsertion(DtorLoc, TypeStr + "::");
3264 Sema::ConditionResult Sema::ActOnConditionVariable(Decl *ConditionVar,
3265 SourceLocation StmtLoc,
3268 CheckConditionVariable(cast<VarDecl>(ConditionVar), StmtLoc, CK);
3270 return ConditionError();
3271 return ConditionResult(*this, ConditionVar, MakeFullExpr(E.get(), StmtLoc),
3272 CK == ConditionKind::ConstexprIf);
3275 /// \brief Check the use of the given variable as a C++ condition in an if,
3276 /// while, do-while, or switch statement.
3277 ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar,
3278 SourceLocation StmtLoc,
3280 if (ConditionVar->isInvalidDecl())
3283 QualType T = ConditionVar->getType();
3285 // C++ [stmt.select]p2:
3286 // The declarator shall not specify a function or an array.
3287 if (T->isFunctionType())
3288 return ExprError(Diag(ConditionVar->getLocation(),
3289 diag::err_invalid_use_of_function_type)
3290 << ConditionVar->getSourceRange());
3291 else if (T->isArrayType())
3292 return ExprError(Diag(ConditionVar->getLocation(),
3293 diag::err_invalid_use_of_array_type)
3294 << ConditionVar->getSourceRange());
3296 ExprResult Condition = DeclRefExpr::Create(
3297 Context, NestedNameSpecifierLoc(), SourceLocation(), ConditionVar,
3298 /*enclosing*/ false, ConditionVar->getLocation(),
3299 ConditionVar->getType().getNonReferenceType(), VK_LValue);
3301 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get()));
3304 case ConditionKind::Boolean:
3305 return CheckBooleanCondition(StmtLoc, Condition.get());
3307 case ConditionKind::ConstexprIf:
3308 return CheckBooleanCondition(StmtLoc, Condition.get(), true);
3310 case ConditionKind::Switch:
3311 return CheckSwitchCondition(StmtLoc, Condition.get());
3314 llvm_unreachable("unexpected condition kind");
3317 /// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
3318 ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr, bool IsConstexpr) {
3320 // The value of a condition that is an initialized declaration in a statement
3321 // other than a switch statement is the value of the declared variable
3322 // implicitly converted to type bool. If that conversion is ill-formed, the
3323 // program is ill-formed.
3324 // The value of a condition that is an expression is the value of the
3325 // expression, implicitly converted to bool.
3327 // FIXME: Return this value to the caller so they don't need to recompute it.
3328 llvm::APSInt Value(/*BitWidth*/1);
3329 return (IsConstexpr && !CondExpr->isValueDependent())
3330 ? CheckConvertedConstantExpression(CondExpr, Context.BoolTy, Value,
3332 : PerformContextuallyConvertToBool(CondExpr);
3335 /// Helper function to determine whether this is the (deprecated) C++
3336 /// conversion from a string literal to a pointer to non-const char or
3337 /// non-const wchar_t (for narrow and wide string literals,
3340 Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) {
3341 // Look inside the implicit cast, if it exists.
3342 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From))
3343 From = Cast->getSubExpr();
3345 // A string literal (2.13.4) that is not a wide string literal can
3346 // be converted to an rvalue of type "pointer to char"; a wide
3347 // string literal can be converted to an rvalue of type "pointer
3348 // to wchar_t" (C++ 4.2p2).
3349 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens()))
3350 if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
3351 if (const BuiltinType *ToPointeeType
3352 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
3353 // This conversion is considered only when there is an
3354 // explicit appropriate pointer target type (C++ 4.2p2).
3355 if (!ToPtrType->getPointeeType().hasQualifiers()) {
3356 switch (StrLit->getKind()) {
3357 case StringLiteral::UTF8:
3358 case StringLiteral::UTF16:
3359 case StringLiteral::UTF32:
3360 // We don't allow UTF literals to be implicitly converted
3362 case StringLiteral::Ascii:
3363 return (ToPointeeType->getKind() == BuiltinType::Char_U ||
3364 ToPointeeType->getKind() == BuiltinType::Char_S);
3365 case StringLiteral::Wide:
3366 return Context.typesAreCompatible(Context.getWideCharType(),
3367 QualType(ToPointeeType, 0));
3375 static ExprResult BuildCXXCastArgument(Sema &S,
3376 SourceLocation CastLoc,
3379 CXXMethodDecl *Method,
3380 DeclAccessPair FoundDecl,
3381 bool HadMultipleCandidates,
3384 default: llvm_unreachable("Unhandled cast kind!");
3385 case CK_ConstructorConversion: {
3386 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method);
3387 SmallVector<Expr*, 8> ConstructorArgs;
3389 if (S.RequireNonAbstractType(CastLoc, Ty,
3390 diag::err_allocation_of_abstract_type))
3393 if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs))
3396 S.CheckConstructorAccess(CastLoc, Constructor, FoundDecl,
3397 InitializedEntity::InitializeTemporary(Ty));
3398 if (S.DiagnoseUseOfDecl(Method, CastLoc))
3401 ExprResult Result = S.BuildCXXConstructExpr(
3402 CastLoc, Ty, FoundDecl, cast<CXXConstructorDecl>(Method),
3403 ConstructorArgs, HadMultipleCandidates,
3404 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3405 CXXConstructExpr::CK_Complete, SourceRange());
3406 if (Result.isInvalid())
3409 return S.MaybeBindToTemporary(Result.getAs<Expr>());
3412 case CK_UserDefinedConversion: {
3413 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
3415 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ nullptr, FoundDecl);
3416 if (S.DiagnoseUseOfDecl(Method, CastLoc))
3419 // Create an implicit call expr that calls it.
3420 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method);
3421 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv,
3422 HadMultipleCandidates);
3423 if (Result.isInvalid())
3425 // Record usage of conversion in an implicit cast.
3426 Result = ImplicitCastExpr::Create(S.Context, Result.get()->getType(),
3427 CK_UserDefinedConversion, Result.get(),
3428 nullptr, Result.get()->getValueKind());
3430 return S.MaybeBindToTemporary(Result.get());
3435 /// PerformImplicitConversion - Perform an implicit conversion of the
3436 /// expression From to the type ToType using the pre-computed implicit
3437 /// conversion sequence ICS. Returns the converted
3438 /// expression. Action is the kind of conversion we're performing,
3439 /// used in the error message.
3441 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
3442 const ImplicitConversionSequence &ICS,
3443 AssignmentAction Action,
3444 CheckedConversionKind CCK) {
3445 switch (ICS.getKind()) {
3446 case ImplicitConversionSequence::StandardConversion: {
3447 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard,
3449 if (Res.isInvalid())
3455 case ImplicitConversionSequence::UserDefinedConversion: {
3457 FunctionDecl *FD = ICS.UserDefined.ConversionFunction;
3459 QualType BeforeToType;
3460 assert(FD && "no conversion function for user-defined conversion seq");
3461 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) {
3462 CastKind = CK_UserDefinedConversion;
3464 // If the user-defined conversion is specified by a conversion function,
3465 // the initial standard conversion sequence converts the source type to
3466 // the implicit object parameter of the conversion function.
3467 BeforeToType = Context.getTagDeclType(Conv->getParent());
3469 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD);
3470 CastKind = CK_ConstructorConversion;
3471 // Do no conversion if dealing with ... for the first conversion.
3472 if (!ICS.UserDefined.EllipsisConversion) {
3473 // If the user-defined conversion is specified by a constructor, the
3474 // initial standard conversion sequence converts the source type to
3475 // the type required by the argument of the constructor
3476 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType();
3479 // Watch out for ellipsis conversion.
3480 if (!ICS.UserDefined.EllipsisConversion) {
3482 PerformImplicitConversion(From, BeforeToType,
3483 ICS.UserDefined.Before, AA_Converting,
3485 if (Res.isInvalid())
3491 = BuildCXXCastArgument(*this,
3492 From->getLocStart(),
3493 ToType.getNonReferenceType(),
3494 CastKind, cast<CXXMethodDecl>(FD),
3495 ICS.UserDefined.FoundConversionFunction,
3496 ICS.UserDefined.HadMultipleCandidates,
3499 if (CastArg.isInvalid())
3502 From = CastArg.get();
3504 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
3505 AA_Converting, CCK);
3508 case ImplicitConversionSequence::AmbiguousConversion:
3509 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(),
3510 PDiag(diag::err_typecheck_ambiguous_condition)
3511 << From->getSourceRange());
3514 case ImplicitConversionSequence::EllipsisConversion:
3515 llvm_unreachable("Cannot perform an ellipsis conversion");
3517 case ImplicitConversionSequence::BadConversion:
3519 DiagnoseAssignmentResult(Incompatible, From->getExprLoc(), ToType,
3520 From->getType(), From, Action);
3521 assert(Diagnosed && "failed to diagnose bad conversion"); (void)Diagnosed;
3525 // Everything went well.
3529 /// PerformImplicitConversion - Perform an implicit conversion of the
3530 /// expression From to the type ToType by following the standard
3531 /// conversion sequence SCS. Returns the converted
3532 /// expression. Flavor is the context in which we're performing this
3533 /// conversion, for use in error messages.
3535 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
3536 const StandardConversionSequence& SCS,
3537 AssignmentAction Action,
3538 CheckedConversionKind CCK) {
3539 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast);
3541 // Overall FIXME: we are recomputing too many types here and doing far too
3542 // much extra work. What this means is that we need to keep track of more
3543 // information that is computed when we try the implicit conversion initially,
3544 // so that we don't need to recompute anything here.
3545 QualType FromType = From->getType();
3547 if (SCS.CopyConstructor) {
3548 // FIXME: When can ToType be a reference type?
3549 assert(!ToType->isReferenceType());
3550 if (SCS.Second == ICK_Derived_To_Base) {
3551 SmallVector<Expr*, 8> ConstructorArgs;
3552 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor),
3553 From, /*FIXME:ConstructLoc*/SourceLocation(),
3556 return BuildCXXConstructExpr(
3557 /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
3558 SCS.FoundCopyConstructor, SCS.CopyConstructor,
3559 ConstructorArgs, /*HadMultipleCandidates*/ false,
3560 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3561 CXXConstructExpr::CK_Complete, SourceRange());
3563 return BuildCXXConstructExpr(
3564 /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
3565 SCS.FoundCopyConstructor, SCS.CopyConstructor,
3566 From, /*HadMultipleCandidates*/ false,
3567 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3568 CXXConstructExpr::CK_Complete, SourceRange());
3571 // Resolve overloaded function references.
3572 if (Context.hasSameType(FromType, Context.OverloadTy)) {
3573 DeclAccessPair Found;
3574 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType,
3579 if (DiagnoseUseOfDecl(Fn, From->getLocStart()))
3582 From = FixOverloadedFunctionReference(From, Found, Fn);
3583 FromType = From->getType();
3586 // If we're converting to an atomic type, first convert to the corresponding
3588 QualType ToAtomicType;
3589 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) {
3590 ToAtomicType = ToType;
3591 ToType = ToAtomic->getValueType();
3594 QualType InitialFromType = FromType;
3595 // Perform the first implicit conversion.
3596 switch (SCS.First) {
3598 if (const AtomicType *FromAtomic = FromType->getAs<AtomicType>()) {
3599 FromType = FromAtomic->getValueType().getUnqualifiedType();
3600 From = ImplicitCastExpr::Create(Context, FromType, CK_AtomicToNonAtomic,
3601 From, /*BasePath=*/nullptr, VK_RValue);
3605 case ICK_Lvalue_To_Rvalue: {
3606 assert(From->getObjectKind() != OK_ObjCProperty);
3607 ExprResult FromRes = DefaultLvalueConversion(From);
3608 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!");
3609 From = FromRes.get();
3610 FromType = From->getType();
3614 case ICK_Array_To_Pointer:
3615 FromType = Context.getArrayDecayedType(FromType);
3616 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay,
3617 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3620 case ICK_Function_To_Pointer:
3621 FromType = Context.getPointerType(FromType);
3622 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay,
3623 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3627 llvm_unreachable("Improper first standard conversion");
3630 // Perform the second implicit conversion
3631 switch (SCS.Second) {
3633 // C++ [except.spec]p5:
3634 // [For] assignment to and initialization of pointers to functions,
3635 // pointers to member functions, and references to functions: the
3636 // target entity shall allow at least the exceptions allowed by the
3637 // source value in the assignment or initialization.
3640 case AA_Initializing:
3641 // Note, function argument passing and returning are initialization.
3645 case AA_Passing_CFAudited:
3646 if (CheckExceptionSpecCompatibility(From, ToType))
3652 // Casts and implicit conversions are not initialization, so are not
3653 // checked for exception specification mismatches.
3656 // Nothing else to do.
3659 case ICK_Integral_Promotion:
3660 case ICK_Integral_Conversion:
3661 if (ToType->isBooleanType()) {
3662 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() &&
3663 SCS.Second == ICK_Integral_Promotion &&
3664 "only enums with fixed underlying type can promote to bool");
3665 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean,
3666 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3668 From = ImpCastExprToType(From, ToType, CK_IntegralCast,
3669 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3673 case ICK_Floating_Promotion:
3674 case ICK_Floating_Conversion:
3675 From = ImpCastExprToType(From, ToType, CK_FloatingCast,
3676 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3679 case ICK_Complex_Promotion:
3680 case ICK_Complex_Conversion: {
3681 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType();
3682 QualType ToEl = ToType->getAs<ComplexType>()->getElementType();
3684 if (FromEl->isRealFloatingType()) {
3685 if (ToEl->isRealFloatingType())
3686 CK = CK_FloatingComplexCast;
3688 CK = CK_FloatingComplexToIntegralComplex;
3689 } else if (ToEl->isRealFloatingType()) {
3690 CK = CK_IntegralComplexToFloatingComplex;
3692 CK = CK_IntegralComplexCast;
3694 From = ImpCastExprToType(From, ToType, CK,
3695 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3699 case ICK_Floating_Integral:
3700 if (ToType->isRealFloatingType())
3701 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating,
3702 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3704 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral,
3705 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3708 case ICK_Compatible_Conversion:
3709 From = ImpCastExprToType(From, ToType, CK_NoOp,
3710 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3713 case ICK_Writeback_Conversion:
3714 case ICK_Pointer_Conversion: {
3715 if (SCS.IncompatibleObjC && Action != AA_Casting) {
3716 // Diagnose incompatible Objective-C conversions
3717 if (Action == AA_Initializing || Action == AA_Assigning)
3718 Diag(From->getLocStart(),
3719 diag::ext_typecheck_convert_incompatible_pointer)
3720 << ToType << From->getType() << Action
3721 << From->getSourceRange() << 0;
3723 Diag(From->getLocStart(),
3724 diag::ext_typecheck_convert_incompatible_pointer)
3725 << From->getType() << ToType << Action
3726 << From->getSourceRange() << 0;
3728 if (From->getType()->isObjCObjectPointerType() &&
3729 ToType->isObjCObjectPointerType())
3730 EmitRelatedResultTypeNote(From);
3731 } else if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers() &&
3732 !CheckObjCARCUnavailableWeakConversion(ToType,
3734 if (Action == AA_Initializing)
3735 Diag(From->getLocStart(),
3736 diag::err_arc_weak_unavailable_assign);
3738 Diag(From->getLocStart(),
3739 diag::err_arc_convesion_of_weak_unavailable)
3740 << (Action == AA_Casting) << From->getType() << ToType
3741 << From->getSourceRange();
3744 CastKind Kind = CK_Invalid;
3745 CXXCastPath BasePath;
3746 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle))
3749 // Make sure we extend blocks if necessary.
3750 // FIXME: doing this here is really ugly.
3751 if (Kind == CK_BlockPointerToObjCPointerCast) {
3752 ExprResult E = From;
3753 (void) PrepareCastToObjCObjectPointer(E);
3756 if (getLangOpts().allowsNonTrivialObjCLifetimeQualifiers())
3757 CheckObjCConversion(SourceRange(), ToType, From, CCK);
3758 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
3763 case ICK_Pointer_Member: {
3764 CastKind Kind = CK_Invalid;
3765 CXXCastPath BasePath;
3766 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle))
3768 if (CheckExceptionSpecCompatibility(From, ToType))
3771 // We may not have been able to figure out what this member pointer resolved
3772 // to up until this exact point. Attempt to lock-in it's inheritance model.
3773 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
3774 (void)isCompleteType(From->getExprLoc(), From->getType());
3775 (void)isCompleteType(From->getExprLoc(), ToType);
3778 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
3783 case ICK_Boolean_Conversion:
3784 // Perform half-to-boolean conversion via float.
3785 if (From->getType()->isHalfType()) {
3786 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).get();
3787 FromType = Context.FloatTy;
3790 From = ImpCastExprToType(From, Context.BoolTy,
3791 ScalarTypeToBooleanCastKind(FromType),
3792 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3795 case ICK_Derived_To_Base: {
3796 CXXCastPath BasePath;
3797 if (CheckDerivedToBaseConversion(From->getType(),
3798 ToType.getNonReferenceType(),
3799 From->getLocStart(),
3800 From->getSourceRange(),
3805 From = ImpCastExprToType(From, ToType.getNonReferenceType(),
3806 CK_DerivedToBase, From->getValueKind(),
3807 &BasePath, CCK).get();
3811 case ICK_Vector_Conversion:
3812 From = ImpCastExprToType(From, ToType, CK_BitCast,
3813 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3816 case ICK_Vector_Splat: {
3817 // Vector splat from any arithmetic type to a vector.
3818 Expr *Elem = prepareVectorSplat(ToType, From).get();
3819 From = ImpCastExprToType(Elem, ToType, CK_VectorSplat, VK_RValue,
3820 /*BasePath=*/nullptr, CCK).get();
3824 case ICK_Complex_Real:
3825 // Case 1. x -> _Complex y
3826 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) {
3827 QualType ElType = ToComplex->getElementType();
3828 bool isFloatingComplex = ElType->isRealFloatingType();
3831 if (Context.hasSameUnqualifiedType(ElType, From->getType())) {
3833 } else if (From->getType()->isRealFloatingType()) {
3834 From = ImpCastExprToType(From, ElType,
3835 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).get();
3837 assert(From->getType()->isIntegerType());
3838 From = ImpCastExprToType(From, ElType,
3839 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).get();
3842 From = ImpCastExprToType(From, ToType,
3843 isFloatingComplex ? CK_FloatingRealToComplex
3844 : CK_IntegralRealToComplex).get();
3846 // Case 2. _Complex x -> y
3848 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>();
3849 assert(FromComplex);
3851 QualType ElType = FromComplex->getElementType();
3852 bool isFloatingComplex = ElType->isRealFloatingType();
3855 From = ImpCastExprToType(From, ElType,
3856 isFloatingComplex ? CK_FloatingComplexToReal
3857 : CK_IntegralComplexToReal,
3858 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3861 if (Context.hasSameUnqualifiedType(ElType, ToType)) {
3863 } else if (ToType->isRealFloatingType()) {
3864 From = ImpCastExprToType(From, ToType,
3865 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating,
3866 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3868 assert(ToType->isIntegerType());
3869 From = ImpCastExprToType(From, ToType,
3870 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast,
3871 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3876 case ICK_Block_Pointer_Conversion: {
3877 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast,
3878 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3882 case ICK_TransparentUnionConversion: {
3883 ExprResult FromRes = From;
3884 Sema::AssignConvertType ConvTy =
3885 CheckTransparentUnionArgumentConstraints(ToType, FromRes);
3886 if (FromRes.isInvalid())
3888 From = FromRes.get();
3889 assert ((ConvTy == Sema::Compatible) &&
3890 "Improper transparent union conversion");
3895 case ICK_Zero_Event_Conversion:
3896 From = ImpCastExprToType(From, ToType,
3898 From->getValueKind()).get();
3901 case ICK_Zero_Queue_Conversion:
3902 From = ImpCastExprToType(From, ToType,
3904 From->getValueKind()).get();
3907 case ICK_Lvalue_To_Rvalue:
3908 case ICK_Array_To_Pointer:
3909 case ICK_Function_To_Pointer:
3910 case ICK_Function_Conversion:
3911 case ICK_Qualification:
3912 case ICK_Num_Conversion_Kinds:
3913 case ICK_C_Only_Conversion:
3914 case ICK_Incompatible_Pointer_Conversion:
3915 llvm_unreachable("Improper second standard conversion");
3918 switch (SCS.Third) {
3923 case ICK_Function_Conversion:
3924 // If both sides are functions (or pointers/references to them), there could
3925 // be incompatible exception declarations.
3926 if (CheckExceptionSpecCompatibility(From, ToType))
3929 From = ImpCastExprToType(From, ToType, CK_NoOp,
3930 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3933 case ICK_Qualification: {
3934 // The qualification keeps the category of the inner expression, unless the
3935 // target type isn't a reference.
3936 ExprValueKind VK = ToType->isReferenceType() ?
3937 From->getValueKind() : VK_RValue;
3938 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context),
3939 CK_NoOp, VK, /*BasePath=*/nullptr, CCK).get();
3941 if (SCS.DeprecatedStringLiteralToCharPtr &&
3942 !getLangOpts().WritableStrings) {
3943 Diag(From->getLocStart(), getLangOpts().CPlusPlus11
3944 ? diag::ext_deprecated_string_literal_conversion
3945 : diag::warn_deprecated_string_literal_conversion)
3946 << ToType.getNonReferenceType();
3953 llvm_unreachable("Improper third standard conversion");
3956 // If this conversion sequence involved a scalar -> atomic conversion, perform
3957 // that conversion now.
3958 if (!ToAtomicType.isNull()) {
3959 assert(Context.hasSameType(
3960 ToAtomicType->castAs<AtomicType>()->getValueType(), From->getType()));
3961 From = ImpCastExprToType(From, ToAtomicType, CK_NonAtomicToAtomic,
3962 VK_RValue, nullptr, CCK).get();
3965 // If this conversion sequence succeeded and involved implicitly converting a
3966 // _Nullable type to a _Nonnull one, complain.
3967 if (CCK == CCK_ImplicitConversion)
3968 diagnoseNullableToNonnullConversion(ToType, InitialFromType,
3969 From->getLocStart());
3974 /// \brief Check the completeness of a type in a unary type trait.
3976 /// If the particular type trait requires a complete type, tries to complete
3977 /// it. If completing the type fails, a diagnostic is emitted and false
3978 /// returned. If completing the type succeeds or no completion was required,
3980 static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, TypeTrait UTT,
3983 // C++0x [meta.unary.prop]p3:
3984 // For all of the class templates X declared in this Clause, instantiating
3985 // that template with a template argument that is a class template
3986 // specialization may result in the implicit instantiation of the template
3987 // argument if and only if the semantics of X require that the argument
3988 // must be a complete type.
3989 // We apply this rule to all the type trait expressions used to implement
3990 // these class templates. We also try to follow any GCC documented behavior
3991 // in these expressions to ensure portability of standard libraries.
3993 default: llvm_unreachable("not a UTT");
3994 // is_complete_type somewhat obviously cannot require a complete type.
3995 case UTT_IsCompleteType:
3998 // These traits are modeled on the type predicates in C++0x
3999 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as
4000 // requiring a complete type, as whether or not they return true cannot be
4001 // impacted by the completeness of the type.
4003 case UTT_IsIntegral:
4004 case UTT_IsFloatingPoint:
4007 case UTT_IsLvalueReference:
4008 case UTT_IsRvalueReference:
4009 case UTT_IsMemberFunctionPointer:
4010 case UTT_IsMemberObjectPointer:
4014 case UTT_IsFunction:
4015 case UTT_IsReference:
4016 case UTT_IsArithmetic:
4017 case UTT_IsFundamental:
4020 case UTT_IsCompound:
4021 case UTT_IsMemberPointer:
4024 // These traits are modeled on type predicates in C++0x [meta.unary.prop]
4025 // which requires some of its traits to have the complete type. However,
4026 // the completeness of the type cannot impact these traits' semantics, and
4027 // so they don't require it. This matches the comments on these traits in
4030 case UTT_IsVolatile:
4032 case UTT_IsUnsigned:
4034 // This type trait always returns false, checking the type is moot.
4035 case UTT_IsInterfaceClass:
4038 // C++14 [meta.unary.prop]:
4039 // If T is a non-union class type, T shall be a complete type.
4041 case UTT_IsPolymorphic:
4042 case UTT_IsAbstract:
4043 if (const auto *RD = ArgTy->getAsCXXRecordDecl())
4045 return !S.RequireCompleteType(
4046 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4049 // C++14 [meta.unary.prop]:
4050 // If T is a class type, T shall be a complete type.
4053 if (ArgTy->getAsCXXRecordDecl())
4054 return !S.RequireCompleteType(
4055 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4058 // C++0x [meta.unary.prop] Table 49 requires the following traits to be
4059 // applied to a complete type.
4060 case UTT_IsAggregate:
4062 case UTT_IsTriviallyCopyable:
4063 case UTT_IsStandardLayout:
4067 case UTT_IsDestructible:
4068 case UTT_IsNothrowDestructible:
4071 // These trait expressions are designed to help implement predicates in
4072 // [meta.unary.prop] despite not being named the same. They are specified
4073 // by both GCC and the Embarcadero C++ compiler, and require the complete
4074 // type due to the overarching C++0x type predicates being implemented
4075 // requiring the complete type.
4076 case UTT_HasNothrowAssign:
4077 case UTT_HasNothrowMoveAssign:
4078 case UTT_HasNothrowConstructor:
4079 case UTT_HasNothrowCopy:
4080 case UTT_HasTrivialAssign:
4081 case UTT_HasTrivialMoveAssign:
4082 case UTT_HasTrivialDefaultConstructor:
4083 case UTT_HasTrivialMoveConstructor:
4084 case UTT_HasTrivialCopy:
4085 case UTT_HasTrivialDestructor:
4086 case UTT_HasVirtualDestructor:
4087 // Arrays of unknown bound are expressly allowed.
4088 QualType ElTy = ArgTy;
4089 if (ArgTy->isIncompleteArrayType())
4090 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType();
4092 // The void type is expressly allowed.
4093 if (ElTy->isVoidType())
4096 return !S.RequireCompleteType(
4097 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr);
4101 static bool HasNoThrowOperator(const RecordType *RT, OverloadedOperatorKind Op,
4102 Sema &Self, SourceLocation KeyLoc, ASTContext &C,
4103 bool (CXXRecordDecl::*HasTrivial)() const,
4104 bool (CXXRecordDecl::*HasNonTrivial)() const,
4105 bool (CXXMethodDecl::*IsDesiredOp)() const)
4107 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
4108 if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)())
4111 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op);
4112 DeclarationNameInfo NameInfo(Name, KeyLoc);
4113 LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName);
4114 if (Self.LookupQualifiedName(Res, RD)) {
4115 bool FoundOperator = false;
4116 Res.suppressDiagnostics();
4117 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end();
4118 Op != OpEnd; ++Op) {
4119 if (isa<FunctionTemplateDecl>(*Op))
4122 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op);
4123 if((Operator->*IsDesiredOp)()) {
4124 FoundOperator = true;
4125 const FunctionProtoType *CPT =
4126 Operator->getType()->getAs<FunctionProtoType>();
4127 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4128 if (!CPT || !CPT->isNothrow(C))
4132 return FoundOperator;
4137 static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
4138 SourceLocation KeyLoc, QualType T) {
4139 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
4141 ASTContext &C = Self.Context;
4143 default: llvm_unreachable("not a UTT");
4144 // Type trait expressions corresponding to the primary type category
4145 // predicates in C++0x [meta.unary.cat].
4147 return T->isVoidType();
4148 case UTT_IsIntegral:
4149 return T->isIntegralType(C);
4150 case UTT_IsFloatingPoint:
4151 return T->isFloatingType();
4153 return T->isArrayType();
4155 return T->isPointerType();
4156 case UTT_IsLvalueReference:
4157 return T->isLValueReferenceType();
4158 case UTT_IsRvalueReference:
4159 return T->isRValueReferenceType();
4160 case UTT_IsMemberFunctionPointer:
4161 return T->isMemberFunctionPointerType();
4162 case UTT_IsMemberObjectPointer:
4163 return T->isMemberDataPointerType();
4165 return T->isEnumeralType();
4167 return T->isUnionType();
4169 return T->isClassType() || T->isStructureType() || T->isInterfaceType();
4170 case UTT_IsFunction:
4171 return T->isFunctionType();
4173 // Type trait expressions which correspond to the convenient composition
4174 // predicates in C++0x [meta.unary.comp].
4175 case UTT_IsReference:
4176 return T->isReferenceType();
4177 case UTT_IsArithmetic:
4178 return T->isArithmeticType() && !T->isEnumeralType();
4179 case UTT_IsFundamental:
4180 return T->isFundamentalType();
4182 return T->isObjectType();
4184 // Note: semantic analysis depends on Objective-C lifetime types to be
4185 // considered scalar types. However, such types do not actually behave
4186 // like scalar types at run time (since they may require retain/release
4187 // operations), so we report them as non-scalar.
4188 if (T->isObjCLifetimeType()) {
4189 switch (T.getObjCLifetime()) {
4190 case Qualifiers::OCL_None:
4191 case Qualifiers::OCL_ExplicitNone:
4194 case Qualifiers::OCL_Strong:
4195 case Qualifiers::OCL_Weak:
4196 case Qualifiers::OCL_Autoreleasing:
4201 return T->isScalarType();
4202 case UTT_IsCompound:
4203 return T->isCompoundType();
4204 case UTT_IsMemberPointer:
4205 return T->isMemberPointerType();
4207 // Type trait expressions which correspond to the type property predicates
4208 // in C++0x [meta.unary.prop].
4210 return T.isConstQualified();
4211 case UTT_IsVolatile:
4212 return T.isVolatileQualified();
4214 return T.isTrivialType(C);
4215 case UTT_IsTriviallyCopyable:
4216 return T.isTriviallyCopyableType(C);
4217 case UTT_IsStandardLayout:
4218 return T->isStandardLayoutType();
4220 return T.isPODType(C);
4222 return T->isLiteralType(C);
4224 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4225 return !RD->isUnion() && RD->isEmpty();
4227 case UTT_IsPolymorphic:
4228 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4229 return !RD->isUnion() && RD->isPolymorphic();
4231 case UTT_IsAbstract:
4232 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4233 return !RD->isUnion() && RD->isAbstract();
4235 case UTT_IsAggregate:
4236 // Report vector extensions and complex types as aggregates because they
4237 // support aggregate initialization. GCC mirrors this behavior for vectors
4238 // but not _Complex.
4239 return T->isAggregateType() || T->isVectorType() || T->isExtVectorType() ||
4240 T->isAnyComplexType();
4241 // __is_interface_class only returns true when CL is invoked in /CLR mode and
4242 // even then only when it is used with the 'interface struct ...' syntax
4243 // Clang doesn't support /CLR which makes this type trait moot.
4244 case UTT_IsInterfaceClass:
4248 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4249 return RD->hasAttr<FinalAttr>();
4252 return T->isSignedIntegerType();
4253 case UTT_IsUnsigned:
4254 return T->isUnsignedIntegerType();
4256 // Type trait expressions which query classes regarding their construction,
4257 // destruction, and copying. Rather than being based directly on the
4258 // related type predicates in the standard, they are specified by both
4259 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those
4262 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
4263 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4265 // Note that these builtins do not behave as documented in g++: if a class
4266 // has both a trivial and a non-trivial special member of a particular kind,
4267 // they return false! For now, we emulate this behavior.
4268 // FIXME: This appears to be a g++ bug: more complex cases reveal that it
4269 // does not correctly compute triviality in the presence of multiple special
4270 // members of the same kind. Revisit this once the g++ bug is fixed.
4271 case UTT_HasTrivialDefaultConstructor:
4272 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4273 // If __is_pod (type) is true then the trait is true, else if type is
4274 // a cv class or union type (or array thereof) with a trivial default
4275 // constructor ([class.ctor]) then the trait is true, else it is false.
4278 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4279 return RD->hasTrivialDefaultConstructor() &&
4280 !RD->hasNonTrivialDefaultConstructor();
4282 case UTT_HasTrivialMoveConstructor:
4283 // This trait is implemented by MSVC 2012 and needed to parse the
4284 // standard library headers. Specifically this is used as the logic
4285 // behind std::is_trivially_move_constructible (20.9.4.3).
4288 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4289 return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor();
4291 case UTT_HasTrivialCopy:
4292 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4293 // If __is_pod (type) is true or type is a reference type then
4294 // the trait is true, else if type is a cv class or union type
4295 // with a trivial copy constructor ([class.copy]) then the trait
4296 // is true, else it is false.
4297 if (T.isPODType(C) || T->isReferenceType())
4299 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4300 return RD->hasTrivialCopyConstructor() &&
4301 !RD->hasNonTrivialCopyConstructor();
4303 case UTT_HasTrivialMoveAssign:
4304 // This trait is implemented by MSVC 2012 and needed to parse the
4305 // standard library headers. Specifically it is used as the logic
4306 // behind std::is_trivially_move_assignable (20.9.4.3)
4309 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4310 return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment();
4312 case UTT_HasTrivialAssign:
4313 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4314 // If type is const qualified or is a reference type then the
4315 // trait is false. Otherwise if __is_pod (type) is true then the
4316 // trait is true, else if type is a cv class or union type with
4317 // a trivial copy assignment ([class.copy]) then the trait is
4318 // true, else it is false.
4319 // Note: the const and reference restrictions are interesting,
4320 // given that const and reference members don't prevent a class
4321 // from having a trivial copy assignment operator (but do cause
4322 // errors if the copy assignment operator is actually used, q.v.
4323 // [class.copy]p12).
4325 if (T.isConstQualified())
4329 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4330 return RD->hasTrivialCopyAssignment() &&
4331 !RD->hasNonTrivialCopyAssignment();
4333 case UTT_IsDestructible:
4334 case UTT_IsNothrowDestructible:
4335 // C++14 [meta.unary.prop]:
4336 // For reference types, is_destructible<T>::value is true.
4337 if (T->isReferenceType())
4340 // Objective-C++ ARC: autorelease types don't require destruction.
4341 if (T->isObjCLifetimeType() &&
4342 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
4345 // C++14 [meta.unary.prop]:
4346 // For incomplete types and function types, is_destructible<T>::value is
4348 if (T->isIncompleteType() || T->isFunctionType())
4351 // C++14 [meta.unary.prop]:
4352 // For object types and given U equal to remove_all_extents_t<T>, if the
4353 // expression std::declval<U&>().~U() is well-formed when treated as an
4354 // unevaluated operand (Clause 5), then is_destructible<T>::value is true
4355 if (auto *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
4356 CXXDestructorDecl *Destructor = Self.LookupDestructor(RD);
4359 // C++14 [dcl.fct.def.delete]p2:
4360 // A program that refers to a deleted function implicitly or
4361 // explicitly, other than to declare it, is ill-formed.
4362 if (Destructor->isDeleted())
4364 if (C.getLangOpts().AccessControl && Destructor->getAccess() != AS_public)
4366 if (UTT == UTT_IsNothrowDestructible) {
4367 const FunctionProtoType *CPT =
4368 Destructor->getType()->getAs<FunctionProtoType>();
4369 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4370 if (!CPT || !CPT->isNothrow(C))
4376 case UTT_HasTrivialDestructor:
4377 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
4378 // If __is_pod (type) is true or type is a reference type
4379 // then the trait is true, else if type is a cv class or union
4380 // type (or array thereof) with a trivial destructor
4381 // ([class.dtor]) then the trait is true, else it is
4383 if (T.isPODType(C) || T->isReferenceType())
4386 // Objective-C++ ARC: autorelease types don't require destruction.
4387 if (T->isObjCLifetimeType() &&
4388 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
4391 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4392 return RD->hasTrivialDestructor();
4394 // TODO: Propagate nothrowness for implicitly declared special members.
4395 case UTT_HasNothrowAssign:
4396 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4397 // If type is const qualified or is a reference type then the
4398 // trait is false. Otherwise if __has_trivial_assign (type)
4399 // is true then the trait is true, else if type is a cv class
4400 // or union type with copy assignment operators that are known
4401 // not to throw an exception then the trait is true, else it is
4403 if (C.getBaseElementType(T).isConstQualified())
4405 if (T->isReferenceType())
4407 if (T.isPODType(C) || T->isObjCLifetimeType())
4410 if (const RecordType *RT = T->getAs<RecordType>())
4411 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
4412 &CXXRecordDecl::hasTrivialCopyAssignment,
4413 &CXXRecordDecl::hasNonTrivialCopyAssignment,
4414 &CXXMethodDecl::isCopyAssignmentOperator);
4416 case UTT_HasNothrowMoveAssign:
4417 // This trait is implemented by MSVC 2012 and needed to parse the
4418 // standard library headers. Specifically this is used as the logic
4419 // behind std::is_nothrow_move_assignable (20.9.4.3).
4423 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>())
4424 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
4425 &CXXRecordDecl::hasTrivialMoveAssignment,
4426 &CXXRecordDecl::hasNonTrivialMoveAssignment,
4427 &CXXMethodDecl::isMoveAssignmentOperator);
4429 case UTT_HasNothrowCopy:
4430 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4431 // If __has_trivial_copy (type) is true then the trait is true, else
4432 // if type is a cv class or union type with copy constructors that are
4433 // known not to throw an exception then the trait is true, else it is
4435 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
4437 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
4438 if (RD->hasTrivialCopyConstructor() &&
4439 !RD->hasNonTrivialCopyConstructor())
4442 bool FoundConstructor = false;
4444 for (const auto *ND : Self.LookupConstructors(RD)) {
4445 // A template constructor is never a copy constructor.
4446 // FIXME: However, it may actually be selected at the actual overload
4447 // resolution point.
4448 if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
4450 // UsingDecl itself is not a constructor
4451 if (isa<UsingDecl>(ND))
4453 auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
4454 if (Constructor->isCopyConstructor(FoundTQs)) {
4455 FoundConstructor = true;
4456 const FunctionProtoType *CPT
4457 = Constructor->getType()->getAs<FunctionProtoType>();
4458 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4461 // TODO: check whether evaluating default arguments can throw.
4462 // For now, we'll be conservative and assume that they can throw.
4463 if (!CPT->isNothrow(C) || CPT->getNumParams() > 1)
4468 return FoundConstructor;
4471 case UTT_HasNothrowConstructor:
4472 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
4473 // If __has_trivial_constructor (type) is true then the trait is
4474 // true, else if type is a cv class or union type (or array
4475 // thereof) with a default constructor that is known not to
4476 // throw an exception then the trait is true, else it is false.
4477 if (T.isPODType(C) || T->isObjCLifetimeType())
4479 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
4480 if (RD->hasTrivialDefaultConstructor() &&
4481 !RD->hasNonTrivialDefaultConstructor())
4484 bool FoundConstructor = false;
4485 for (const auto *ND : Self.LookupConstructors(RD)) {
4486 // FIXME: In C++0x, a constructor template can be a default constructor.
4487 if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
4489 // UsingDecl itself is not a constructor
4490 if (isa<UsingDecl>(ND))
4492 auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
4493 if (Constructor->isDefaultConstructor()) {
4494 FoundConstructor = true;
4495 const FunctionProtoType *CPT
4496 = Constructor->getType()->getAs<FunctionProtoType>();
4497 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4500 // FIXME: check whether evaluating default arguments can throw.
4501 // For now, we'll be conservative and assume that they can throw.
4502 if (!CPT->isNothrow(C) || CPT->getNumParams() > 0)
4506 return FoundConstructor;
4509 case UTT_HasVirtualDestructor:
4510 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4511 // If type is a class type with a virtual destructor ([class.dtor])
4512 // then the trait is true, else it is false.
4513 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4514 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
4515 return Destructor->isVirtual();
4518 // These type trait expressions are modeled on the specifications for the
4519 // Embarcadero C++0x type trait functions:
4520 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4521 case UTT_IsCompleteType:
4522 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_):
4523 // Returns True if and only if T is a complete type at the point of the
4525 return !T->isIncompleteType();
4529 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
4530 QualType RhsT, SourceLocation KeyLoc);
4532 static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc,
4533 ArrayRef<TypeSourceInfo *> Args,
4534 SourceLocation RParenLoc) {
4535 if (Kind <= UTT_Last)
4536 return EvaluateUnaryTypeTrait(S, Kind, KWLoc, Args[0]->getType());
4538 if (Kind <= BTT_Last)
4539 return EvaluateBinaryTypeTrait(S, Kind, Args[0]->getType(),
4540 Args[1]->getType(), RParenLoc);
4543 case clang::TT_IsConstructible:
4544 case clang::TT_IsNothrowConstructible:
4545 case clang::TT_IsTriviallyConstructible: {
4546 // C++11 [meta.unary.prop]:
4547 // is_trivially_constructible is defined as:
4549 // is_constructible<T, Args...>::value is true and the variable
4550 // definition for is_constructible, as defined below, is known to call
4551 // no operation that is not trivial.
4553 // The predicate condition for a template specialization
4554 // is_constructible<T, Args...> shall be satisfied if and only if the
4555 // following variable definition would be well-formed for some invented
4558 // T t(create<Args>()...);
4559 assert(!Args.empty());
4561 // Precondition: T and all types in the parameter pack Args shall be
4562 // complete types, (possibly cv-qualified) void, or arrays of
4564 for (const auto *TSI : Args) {
4565 QualType ArgTy = TSI->getType();
4566 if (ArgTy->isVoidType() || ArgTy->isIncompleteArrayType())
4569 if (S.RequireCompleteType(KWLoc, ArgTy,
4570 diag::err_incomplete_type_used_in_type_trait_expr))
4574 // Make sure the first argument is not incomplete nor a function type.
4575 QualType T = Args[0]->getType();
4576 if (T->isIncompleteType() || T->isFunctionType())
4579 // Make sure the first argument is not an abstract type.
4580 CXXRecordDecl *RD = T->getAsCXXRecordDecl();
4581 if (RD && RD->isAbstract())
4584 SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs;
4585 SmallVector<Expr *, 2> ArgExprs;
4586 ArgExprs.reserve(Args.size() - 1);
4587 for (unsigned I = 1, N = Args.size(); I != N; ++I) {
4588 QualType ArgTy = Args[I]->getType();
4589 if (ArgTy->isObjectType() || ArgTy->isFunctionType())
4590 ArgTy = S.Context.getRValueReferenceType(ArgTy);
4591 OpaqueArgExprs.push_back(
4592 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(),
4593 ArgTy.getNonLValueExprType(S.Context),
4594 Expr::getValueKindForType(ArgTy)));
4596 for (Expr &E : OpaqueArgExprs)
4597 ArgExprs.push_back(&E);
4599 // Perform the initialization in an unevaluated context within a SFINAE
4600 // trap at translation unit scope.
4601 EnterExpressionEvaluationContext Unevaluated(
4602 S, Sema::ExpressionEvaluationContext::Unevaluated);
4603 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
4604 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl());
4605 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0]));
4606 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc,
4608 InitializationSequence Init(S, To, InitKind, ArgExprs);
4612 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs);
4613 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
4616 if (Kind == clang::TT_IsConstructible)
4619 if (Kind == clang::TT_IsNothrowConstructible)
4620 return S.canThrow(Result.get()) == CT_Cannot;
4622 if (Kind == clang::TT_IsTriviallyConstructible) {
4623 // Under Objective-C ARC and Weak, if the destination has non-trivial
4624 // Objective-C lifetime, this is a non-trivial construction.
4625 if (T.getNonReferenceType().hasNonTrivialObjCLifetime())
4628 // The initialization succeeded; now make sure there are no non-trivial
4630 return !Result.get()->hasNonTrivialCall(S.Context);
4633 llvm_unreachable("unhandled type trait");
4636 default: llvm_unreachable("not a TT");
4642 ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4643 ArrayRef<TypeSourceInfo *> Args,
4644 SourceLocation RParenLoc) {
4645 QualType ResultType = Context.getLogicalOperationType();
4647 if (Kind <= UTT_Last && !CheckUnaryTypeTraitTypeCompleteness(
4648 *this, Kind, KWLoc, Args[0]->getType()))
4651 bool Dependent = false;
4652 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
4653 if (Args[I]->getType()->isDependentType()) {
4659 bool Result = false;
4661 Result = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc);
4663 return TypeTraitExpr::Create(Context, ResultType, KWLoc, Kind, Args,
4667 ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4668 ArrayRef<ParsedType> Args,
4669 SourceLocation RParenLoc) {
4670 SmallVector<TypeSourceInfo *, 4> ConvertedArgs;
4671 ConvertedArgs.reserve(Args.size());
4673 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
4674 TypeSourceInfo *TInfo;
4675 QualType T = GetTypeFromParser(Args[I], &TInfo);
4677 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc);
4679 ConvertedArgs.push_back(TInfo);
4682 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc);
4685 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
4686 QualType RhsT, SourceLocation KeyLoc) {
4687 assert(!LhsT->isDependentType() && !RhsT->isDependentType() &&
4688 "Cannot evaluate traits of dependent types");
4691 case BTT_IsBaseOf: {
4692 // C++0x [meta.rel]p2
4693 // Base is a base class of Derived without regard to cv-qualifiers or
4694 // Base and Derived are not unions and name the same class type without
4695 // regard to cv-qualifiers.
4697 const RecordType *lhsRecord = LhsT->getAs<RecordType>();
4698 if (!lhsRecord) return false;
4700 const RecordType *rhsRecord = RhsT->getAs<RecordType>();
4701 if (!rhsRecord) return false;
4703 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT)
4704 == (lhsRecord == rhsRecord));
4706 if (lhsRecord == rhsRecord)
4707 return !lhsRecord->getDecl()->isUnion();
4709 // C++0x [meta.rel]p2:
4710 // If Base and Derived are class types and are different types
4711 // (ignoring possible cv-qualifiers) then Derived shall be a
4713 if (Self.RequireCompleteType(KeyLoc, RhsT,
4714 diag::err_incomplete_type_used_in_type_trait_expr))
4717 return cast<CXXRecordDecl>(rhsRecord->getDecl())
4718 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl()));
4721 return Self.Context.hasSameType(LhsT, RhsT);
4722 case BTT_TypeCompatible:
4723 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(),
4724 RhsT.getUnqualifiedType());
4725 case BTT_IsConvertible:
4726 case BTT_IsConvertibleTo: {
4727 // C++0x [meta.rel]p4:
4728 // Given the following function prototype:
4730 // template <class T>
4731 // typename add_rvalue_reference<T>::type create();
4733 // the predicate condition for a template specialization
4734 // is_convertible<From, To> shall be satisfied if and only if
4735 // the return expression in the following code would be
4736 // well-formed, including any implicit conversions to the return
4737 // type of the function:
4740 // return create<From>();
4743 // Access checking is performed as if in a context unrelated to To and
4744 // From. Only the validity of the immediate context of the expression
4745 // of the return-statement (including conversions to the return type)
4748 // We model the initialization as a copy-initialization of a temporary
4749 // of the appropriate type, which for this expression is identical to the
4750 // return statement (since NRVO doesn't apply).
4752 // Functions aren't allowed to return function or array types.
4753 if (RhsT->isFunctionType() || RhsT->isArrayType())
4756 // A return statement in a void function must have void type.
4757 if (RhsT->isVoidType())
4758 return LhsT->isVoidType();
4760 // A function definition requires a complete, non-abstract return type.
4761 if (!Self.isCompleteType(KeyLoc, RhsT) || Self.isAbstractType(KeyLoc, RhsT))
4764 // Compute the result of add_rvalue_reference.
4765 if (LhsT->isObjectType() || LhsT->isFunctionType())
4766 LhsT = Self.Context.getRValueReferenceType(LhsT);
4768 // Build a fake source and destination for initialization.
4769 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT));
4770 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
4771 Expr::getValueKindForType(LhsT));
4772 Expr *FromPtr = &From;
4773 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc,
4776 // Perform the initialization in an unevaluated context within a SFINAE
4777 // trap at translation unit scope.
4778 EnterExpressionEvaluationContext Unevaluated(
4779 Self, Sema::ExpressionEvaluationContext::Unevaluated);
4780 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
4781 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
4782 InitializationSequence Init(Self, To, Kind, FromPtr);
4786 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr);
4787 return !Result.isInvalid() && !SFINAE.hasErrorOccurred();
4790 case BTT_IsAssignable:
4791 case BTT_IsNothrowAssignable:
4792 case BTT_IsTriviallyAssignable: {
4793 // C++11 [meta.unary.prop]p3:
4794 // is_trivially_assignable is defined as:
4795 // is_assignable<T, U>::value is true and the assignment, as defined by
4796 // is_assignable, is known to call no operation that is not trivial
4798 // is_assignable is defined as:
4799 // The expression declval<T>() = declval<U>() is well-formed when
4800 // treated as an unevaluated operand (Clause 5).
4802 // For both, T and U shall be complete types, (possibly cv-qualified)
4803 // void, or arrays of unknown bound.
4804 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() &&
4805 Self.RequireCompleteType(KeyLoc, LhsT,
4806 diag::err_incomplete_type_used_in_type_trait_expr))
4808 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() &&
4809 Self.RequireCompleteType(KeyLoc, RhsT,
4810 diag::err_incomplete_type_used_in_type_trait_expr))
4813 // cv void is never assignable.
4814 if (LhsT->isVoidType() || RhsT->isVoidType())
4817 // Build expressions that emulate the effect of declval<T>() and
4819 if (LhsT->isObjectType() || LhsT->isFunctionType())
4820 LhsT = Self.Context.getRValueReferenceType(LhsT);
4821 if (RhsT->isObjectType() || RhsT->isFunctionType())
4822 RhsT = Self.Context.getRValueReferenceType(RhsT);
4823 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
4824 Expr::getValueKindForType(LhsT));
4825 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context),
4826 Expr::getValueKindForType(RhsT));
4828 // Attempt the assignment in an unevaluated context within a SFINAE
4829 // trap at translation unit scope.
4830 EnterExpressionEvaluationContext Unevaluated(
4831 Self, Sema::ExpressionEvaluationContext::Unevaluated);
4832 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
4833 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
4834 ExprResult Result = Self.BuildBinOp(/*S=*/nullptr, KeyLoc, BO_Assign, &Lhs,
4836 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
4839 if (BTT == BTT_IsAssignable)
4842 if (BTT == BTT_IsNothrowAssignable)
4843 return Self.canThrow(Result.get()) == CT_Cannot;
4845 if (BTT == BTT_IsTriviallyAssignable) {
4846 // Under Objective-C ARC and Weak, if the destination has non-trivial
4847 // Objective-C lifetime, this is a non-trivial assignment.
4848 if (LhsT.getNonReferenceType().hasNonTrivialObjCLifetime())
4851 return !Result.get()->hasNonTrivialCall(Self.Context);
4854 llvm_unreachable("unhandled type trait");
4857 default: llvm_unreachable("not a BTT");
4859 llvm_unreachable("Unknown type trait or not implemented");
4862 ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT,
4863 SourceLocation KWLoc,
4866 SourceLocation RParen) {
4867 TypeSourceInfo *TSInfo;
4868 QualType T = GetTypeFromParser(Ty, &TSInfo);
4870 TSInfo = Context.getTrivialTypeSourceInfo(T);
4872 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen);
4875 static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT,
4876 QualType T, Expr *DimExpr,
4877 SourceLocation KeyLoc) {
4878 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
4882 if (T->isArrayType()) {
4884 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
4886 T = AT->getElementType();
4892 case ATT_ArrayExtent: {
4895 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value,
4896 diag::err_dimension_expr_not_constant_integer,
4899 if (Value.isSigned() && Value.isNegative()) {
4900 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer)
4901 << DimExpr->getSourceRange();
4904 Dim = Value.getLimitedValue();
4906 if (T->isArrayType()) {
4908 bool Matched = false;
4909 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
4915 T = AT->getElementType();
4918 if (Matched && T->isArrayType()) {
4919 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T))
4920 return CAT->getSize().getLimitedValue();
4926 llvm_unreachable("Unknown type trait or not implemented");
4929 ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT,
4930 SourceLocation KWLoc,
4931 TypeSourceInfo *TSInfo,
4933 SourceLocation RParen) {
4934 QualType T = TSInfo->getType();
4936 // FIXME: This should likely be tracked as an APInt to remove any host
4937 // assumptions about the width of size_t on the target.
4939 if (!T->isDependentType())
4940 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc);
4942 // While the specification for these traits from the Embarcadero C++
4943 // compiler's documentation says the return type is 'unsigned int', Clang
4944 // returns 'size_t'. On Windows, the primary platform for the Embarcadero
4945 // compiler, there is no difference. On several other platforms this is an
4946 // important distinction.
4947 return new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, DimExpr,
4948 RParen, Context.getSizeType());
4951 ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET,
4952 SourceLocation KWLoc,
4954 SourceLocation RParen) {
4955 // If error parsing the expression, ignore.
4959 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen);
4964 static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) {
4966 case ET_IsLValueExpr: return E->isLValue();
4967 case ET_IsRValueExpr: return E->isRValue();
4969 llvm_unreachable("Expression trait not covered by switch");
4972 ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET,
4973 SourceLocation KWLoc,
4975 SourceLocation RParen) {
4976 if (Queried->isTypeDependent()) {
4977 // Delay type-checking for type-dependent expressions.
4978 } else if (Queried->getType()->isPlaceholderType()) {
4979 ExprResult PE = CheckPlaceholderExpr(Queried);
4980 if (PE.isInvalid()) return ExprError();
4981 return BuildExpressionTrait(ET, KWLoc, PE.get(), RParen);
4984 bool Value = EvaluateExpressionTrait(ET, Queried);
4986 return new (Context)
4987 ExpressionTraitExpr(KWLoc, ET, Queried, Value, RParen, Context.BoolTy);
4990 QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS,
4994 assert(!LHS.get()->getType()->isPlaceholderType() &&
4995 !RHS.get()->getType()->isPlaceholderType() &&
4996 "placeholders should have been weeded out by now");
4998 // The LHS undergoes lvalue conversions if this is ->*, and undergoes the
4999 // temporary materialization conversion otherwise.
5001 LHS = DefaultLvalueConversion(LHS.get());
5002 else if (LHS.get()->isRValue())
5003 LHS = TemporaryMaterializationConversion(LHS.get());
5004 if (LHS.isInvalid())
5007 // The RHS always undergoes lvalue conversions.
5008 RHS = DefaultLvalueConversion(RHS.get());
5009 if (RHS.isInvalid()) return QualType();
5011 const char *OpSpelling = isIndirect ? "->*" : ".*";
5013 // The binary operator .* [p3: ->*] binds its second operand, which shall
5014 // be of type "pointer to member of T" (where T is a completely-defined
5015 // class type) [...]
5016 QualType RHSType = RHS.get()->getType();
5017 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>();
5019 Diag(Loc, diag::err_bad_memptr_rhs)
5020 << OpSpelling << RHSType << RHS.get()->getSourceRange();
5024 QualType Class(MemPtr->getClass(), 0);
5026 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the
5027 // member pointer points must be completely-defined. However, there is no
5028 // reason for this semantic distinction, and the rule is not enforced by
5029 // other compilers. Therefore, we do not check this property, as it is
5030 // likely to be considered a defect.
5033 // [...] to its first operand, which shall be of class T or of a class of
5034 // which T is an unambiguous and accessible base class. [p3: a pointer to
5036 QualType LHSType = LHS.get()->getType();
5038 if (const PointerType *Ptr = LHSType->getAs<PointerType>())
5039 LHSType = Ptr->getPointeeType();
5041 Diag(Loc, diag::err_bad_memptr_lhs)
5042 << OpSpelling << 1 << LHSType
5043 << FixItHint::CreateReplacement(SourceRange(Loc), ".*");
5048 if (!Context.hasSameUnqualifiedType(Class, LHSType)) {
5049 // If we want to check the hierarchy, we need a complete type.
5050 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs,
5051 OpSpelling, (int)isIndirect)) {
5055 if (!IsDerivedFrom(Loc, LHSType, Class)) {
5056 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling
5057 << (int)isIndirect << LHS.get()->getType();
5061 CXXCastPath BasePath;
5062 if (CheckDerivedToBaseConversion(LHSType, Class, Loc,
5063 SourceRange(LHS.get()->getLocStart(),
5064 RHS.get()->getLocEnd()),
5068 // Cast LHS to type of use.
5069 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class;
5070 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind();
5071 LHS = ImpCastExprToType(LHS.get(), UseType, CK_DerivedToBase, VK,
5075 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) {
5076 // Diagnose use of pointer-to-member type which when used as
5077 // the functional cast in a pointer-to-member expression.
5078 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect;
5083 // The result is an object or a function of the type specified by the
5085 // The cv qualifiers are the union of those in the pointer and the left side,
5086 // in accordance with 5.5p5 and 5.2.5.
5087 QualType Result = MemPtr->getPointeeType();
5088 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers());
5090 // C++0x [expr.mptr.oper]p6:
5091 // In a .* expression whose object expression is an rvalue, the program is
5092 // ill-formed if the second operand is a pointer to member function with
5093 // ref-qualifier &. In a ->* expression or in a .* expression whose object
5094 // expression is an lvalue, the program is ill-formed if the second operand
5095 // is a pointer to member function with ref-qualifier &&.
5096 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) {
5097 switch (Proto->getRefQualifier()) {
5103 if (!isIndirect && !LHS.get()->Classify(Context).isLValue())
5104 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
5105 << RHSType << 1 << LHS.get()->getSourceRange();
5109 if (isIndirect || !LHS.get()->Classify(Context).isRValue())
5110 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
5111 << RHSType << 0 << LHS.get()->getSourceRange();
5116 // C++ [expr.mptr.oper]p6:
5117 // The result of a .* expression whose second operand is a pointer
5118 // to a data member is of the same value category as its
5119 // first operand. The result of a .* expression whose second
5120 // operand is a pointer to a member function is a prvalue. The
5121 // result of an ->* expression is an lvalue if its second operand
5122 // is a pointer to data member and a prvalue otherwise.
5123 if (Result->isFunctionType()) {
5125 return Context.BoundMemberTy;
5126 } else if (isIndirect) {
5129 VK = LHS.get()->getValueKind();
5135 /// \brief Try to convert a type to another according to C++11 5.16p3.
5137 /// This is part of the parameter validation for the ? operator. If either
5138 /// value operand is a class type, the two operands are attempted to be
5139 /// converted to each other. This function does the conversion in one direction.
5140 /// It returns true if the program is ill-formed and has already been diagnosed
5142 static bool TryClassUnification(Sema &Self, Expr *From, Expr *To,
5143 SourceLocation QuestionLoc,
5144 bool &HaveConversion,
5146 HaveConversion = false;
5147 ToType = To->getType();
5149 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(),
5152 // The process for determining whether an operand expression E1 of type T1
5153 // can be converted to match an operand expression E2 of type T2 is defined
5155 // -- If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
5156 // implicitly converted to type "lvalue reference to T2", subject to the
5157 // constraint that in the conversion the reference must bind directly to
5159 // -- If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
5160 // implicitly conveted to the type "rvalue reference to R2", subject to
5161 // the constraint that the reference must bind directly.
5162 if (To->isLValue() || To->isXValue()) {
5163 QualType T = To->isLValue() ? Self.Context.getLValueReferenceType(ToType)
5164 : Self.Context.getRValueReferenceType(ToType);
5166 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
5168 InitializationSequence InitSeq(Self, Entity, Kind, From);
5169 if (InitSeq.isDirectReferenceBinding()) {
5171 HaveConversion = true;
5175 if (InitSeq.isAmbiguous())
5176 return InitSeq.Diagnose(Self, Entity, Kind, From);
5179 // -- If E2 is an rvalue, or if the conversion above cannot be done:
5180 // -- if E1 and E2 have class type, and the underlying class types are
5181 // the same or one is a base class of the other:
5182 QualType FTy = From->getType();
5183 QualType TTy = To->getType();
5184 const RecordType *FRec = FTy->getAs<RecordType>();
5185 const RecordType *TRec = TTy->getAs<RecordType>();
5186 bool FDerivedFromT = FRec && TRec && FRec != TRec &&
5187 Self.IsDerivedFrom(QuestionLoc, FTy, TTy);
5188 if (FRec && TRec && (FRec == TRec || FDerivedFromT ||
5189 Self.IsDerivedFrom(QuestionLoc, TTy, FTy))) {
5190 // E1 can be converted to match E2 if the class of T2 is the
5191 // same type as, or a base class of, the class of T1, and
5193 if (FRec == TRec || FDerivedFromT) {
5194 if (TTy.isAtLeastAsQualifiedAs(FTy)) {
5195 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
5196 InitializationSequence InitSeq(Self, Entity, Kind, From);
5198 HaveConversion = true;
5202 if (InitSeq.isAmbiguous())
5203 return InitSeq.Diagnose(Self, Entity, Kind, From);
5210 // -- Otherwise: E1 can be converted to match E2 if E1 can be
5211 // implicitly converted to the type that expression E2 would have
5212 // if E2 were converted to an rvalue (or the type it has, if E2 is
5215 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not
5216 // to the array-to-pointer or function-to-pointer conversions.
5217 TTy = TTy.getNonLValueExprType(Self.Context);
5219 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
5220 InitializationSequence InitSeq(Self, Entity, Kind, From);
5221 HaveConversion = !InitSeq.Failed();
5223 if (InitSeq.isAmbiguous())
5224 return InitSeq.Diagnose(Self, Entity, Kind, From);
5229 /// \brief Try to find a common type for two according to C++0x 5.16p5.
5231 /// This is part of the parameter validation for the ? operator. If either
5232 /// value operand is a class type, overload resolution is used to find a
5233 /// conversion to a common type.
5234 static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS,
5235 SourceLocation QuestionLoc) {
5236 Expr *Args[2] = { LHS.get(), RHS.get() };
5237 OverloadCandidateSet CandidateSet(QuestionLoc,
5238 OverloadCandidateSet::CSK_Operator);
5239 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args,
5242 OverloadCandidateSet::iterator Best;
5243 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) {
5245 // We found a match. Perform the conversions on the arguments and move on.
5247 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0],
5248 Best->Conversions[0], Sema::AA_Converting);
5249 if (LHSRes.isInvalid())
5254 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1],
5255 Best->Conversions[1], Sema::AA_Converting);
5256 if (RHSRes.isInvalid())
5260 Self.MarkFunctionReferenced(QuestionLoc, Best->Function);
5264 case OR_No_Viable_Function:
5266 // Emit a better diagnostic if one of the expressions is a null pointer
5267 // constant and the other is a pointer type. In this case, the user most
5268 // likely forgot to take the address of the other expression.
5269 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
5272 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
5273 << LHS.get()->getType() << RHS.get()->getType()
5274 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5278 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl)
5279 << LHS.get()->getType() << RHS.get()->getType()
5280 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5281 // FIXME: Print the possible common types by printing the return types of
5282 // the viable candidates.
5286 llvm_unreachable("Conditional operator has only built-in overloads");
5291 /// \brief Perform an "extended" implicit conversion as returned by
5292 /// TryClassUnification.
5293 static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) {
5294 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
5295 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(),
5297 Expr *Arg = E.get();
5298 InitializationSequence InitSeq(Self, Entity, Kind, Arg);
5299 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, Arg);
5300 if (Result.isInvalid())
5307 /// \brief Check the operands of ?: under C++ semantics.
5309 /// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y
5310 /// extension. In this case, LHS == Cond. (But they're not aliases.)
5311 QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
5312 ExprResult &RHS, ExprValueKind &VK,
5314 SourceLocation QuestionLoc) {
5315 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++
5316 // interface pointers.
5318 // C++11 [expr.cond]p1
5319 // The first expression is contextually converted to bool.
5320 if (!Cond.get()->isTypeDependent()) {
5321 ExprResult CondRes = CheckCXXBooleanCondition(Cond.get());
5322 if (CondRes.isInvalid())
5331 // Either of the arguments dependent?
5332 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent())
5333 return Context.DependentTy;
5335 // C++11 [expr.cond]p2
5336 // If either the second or the third operand has type (cv) void, ...
5337 QualType LTy = LHS.get()->getType();
5338 QualType RTy = RHS.get()->getType();
5339 bool LVoid = LTy->isVoidType();
5340 bool RVoid = RTy->isVoidType();
5341 if (LVoid || RVoid) {
5342 // ... one of the following shall hold:
5343 // -- The second or the third operand (but not both) is a (possibly
5344 // parenthesized) throw-expression; the result is of the type
5345 // and value category of the other.
5346 bool LThrow = isa<CXXThrowExpr>(LHS.get()->IgnoreParenImpCasts());
5347 bool RThrow = isa<CXXThrowExpr>(RHS.get()->IgnoreParenImpCasts());
5348 if (LThrow != RThrow) {
5349 Expr *NonThrow = LThrow ? RHS.get() : LHS.get();
5350 VK = NonThrow->getValueKind();
5351 // DR (no number yet): the result is a bit-field if the
5352 // non-throw-expression operand is a bit-field.
5353 OK = NonThrow->getObjectKind();
5354 return NonThrow->getType();
5357 // -- Both the second and third operands have type void; the result is of
5358 // type void and is a prvalue.
5360 return Context.VoidTy;
5362 // Neither holds, error.
5363 Diag(QuestionLoc, diag::err_conditional_void_nonvoid)
5364 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1)
5365 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5371 // C++11 [expr.cond]p3
5372 // Otherwise, if the second and third operand have different types, and
5373 // either has (cv) class type [...] an attempt is made to convert each of
5374 // those operands to the type of the other.
5375 if (!Context.hasSameType(LTy, RTy) &&
5376 (LTy->isRecordType() || RTy->isRecordType())) {
5377 // These return true if a single direction is already ambiguous.
5378 QualType L2RType, R2LType;
5379 bool HaveL2R, HaveR2L;
5380 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType))
5382 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType))
5385 // If both can be converted, [...] the program is ill-formed.
5386 if (HaveL2R && HaveR2L) {
5387 Diag(QuestionLoc, diag::err_conditional_ambiguous)
5388 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5392 // If exactly one conversion is possible, that conversion is applied to
5393 // the chosen operand and the converted operands are used in place of the
5394 // original operands for the remainder of this section.
5396 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid())
5398 LTy = LHS.get()->getType();
5399 } else if (HaveR2L) {
5400 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid())
5402 RTy = RHS.get()->getType();
5406 // C++11 [expr.cond]p3
5407 // if both are glvalues of the same value category and the same type except
5408 // for cv-qualification, an attempt is made to convert each of those
5409 // operands to the type of the other.
5411 // Resolving a defect in P0012R1: we extend this to cover all cases where
5412 // one of the operands is reference-compatible with the other, in order
5413 // to support conditionals between functions differing in noexcept.
5414 ExprValueKind LVK = LHS.get()->getValueKind();
5415 ExprValueKind RVK = RHS.get()->getValueKind();
5416 if (!Context.hasSameType(LTy, RTy) &&
5417 LVK == RVK && LVK != VK_RValue) {
5418 // DerivedToBase was already handled by the class-specific case above.
5419 // FIXME: Should we allow ObjC conversions here?
5420 bool DerivedToBase, ObjCConversion, ObjCLifetimeConversion;
5421 if (CompareReferenceRelationship(
5422 QuestionLoc, LTy, RTy, DerivedToBase,
5423 ObjCConversion, ObjCLifetimeConversion) == Ref_Compatible &&
5424 !DerivedToBase && !ObjCConversion && !ObjCLifetimeConversion &&
5425 // [...] subject to the constraint that the reference must bind
5427 !RHS.get()->refersToBitField() &&
5428 !RHS.get()->refersToVectorElement()) {
5429 RHS = ImpCastExprToType(RHS.get(), LTy, CK_NoOp, RVK);
5430 RTy = RHS.get()->getType();
5431 } else if (CompareReferenceRelationship(
5432 QuestionLoc, RTy, LTy, DerivedToBase,
5433 ObjCConversion, ObjCLifetimeConversion) == Ref_Compatible &&
5434 !DerivedToBase && !ObjCConversion && !ObjCLifetimeConversion &&
5435 !LHS.get()->refersToBitField() &&
5436 !LHS.get()->refersToVectorElement()) {
5437 LHS = ImpCastExprToType(LHS.get(), RTy, CK_NoOp, LVK);
5438 LTy = LHS.get()->getType();
5442 // C++11 [expr.cond]p4
5443 // If the second and third operands are glvalues of the same value
5444 // category and have the same type, the result is of that type and
5445 // value category and it is a bit-field if the second or the third
5446 // operand is a bit-field, or if both are bit-fields.
5447 // We only extend this to bitfields, not to the crazy other kinds of
5449 bool Same = Context.hasSameType(LTy, RTy);
5450 if (Same && LVK == RVK && LVK != VK_RValue &&
5451 LHS.get()->isOrdinaryOrBitFieldObject() &&
5452 RHS.get()->isOrdinaryOrBitFieldObject()) {
5453 VK = LHS.get()->getValueKind();
5454 if (LHS.get()->getObjectKind() == OK_BitField ||
5455 RHS.get()->getObjectKind() == OK_BitField)
5458 // If we have function pointer types, unify them anyway to unify their
5459 // exception specifications, if any.
5460 if (LTy->isFunctionPointerType() || LTy->isMemberFunctionPointerType()) {
5461 Qualifiers Qs = LTy.getQualifiers();
5462 LTy = FindCompositePointerType(QuestionLoc, LHS, RHS,
5463 /*ConvertArgs*/false);
5464 LTy = Context.getQualifiedType(LTy, Qs);
5466 assert(!LTy.isNull() && "failed to find composite pointer type for "
5467 "canonically equivalent function ptr types");
5468 assert(Context.hasSameType(LTy, RTy) && "bad composite pointer type");
5474 // C++11 [expr.cond]p5
5475 // Otherwise, the result is a prvalue. If the second and third operands
5476 // do not have the same type, and either has (cv) class type, ...
5477 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) {
5478 // ... overload resolution is used to determine the conversions (if any)
5479 // to be applied to the operands. If the overload resolution fails, the
5480 // program is ill-formed.
5481 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc))
5485 // C++11 [expr.cond]p6
5486 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard
5487 // conversions are performed on the second and third operands.
5488 LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
5489 RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
5490 if (LHS.isInvalid() || RHS.isInvalid())
5492 LTy = LHS.get()->getType();
5493 RTy = RHS.get()->getType();
5495 // After those conversions, one of the following shall hold:
5496 // -- The second and third operands have the same type; the result
5497 // is of that type. If the operands have class type, the result
5498 // is a prvalue temporary of the result type, which is
5499 // copy-initialized from either the second operand or the third
5500 // operand depending on the value of the first operand.
5501 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) {
5502 if (LTy->isRecordType()) {
5503 // The operands have class type. Make a temporary copy.
5504 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy);
5506 ExprResult LHSCopy = PerformCopyInitialization(Entity,
5509 if (LHSCopy.isInvalid())
5512 ExprResult RHSCopy = PerformCopyInitialization(Entity,
5515 if (RHSCopy.isInvalid())
5522 // If we have function pointer types, unify them anyway to unify their
5523 // exception specifications, if any.
5524 if (LTy->isFunctionPointerType() || LTy->isMemberFunctionPointerType()) {
5525 LTy = FindCompositePointerType(QuestionLoc, LHS, RHS);
5526 assert(!LTy.isNull() && "failed to find composite pointer type for "
5527 "canonically equivalent function ptr types");
5533 // Extension: conditional operator involving vector types.
5534 if (LTy->isVectorType() || RTy->isVectorType())
5535 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false,
5536 /*AllowBothBool*/true,
5537 /*AllowBoolConversions*/false);
5539 // -- The second and third operands have arithmetic or enumeration type;
5540 // the usual arithmetic conversions are performed to bring them to a
5541 // common type, and the result is of that type.
5542 if (LTy->isArithmeticType() && RTy->isArithmeticType()) {
5543 QualType ResTy = UsualArithmeticConversions(LHS, RHS);
5544 if (LHS.isInvalid() || RHS.isInvalid())
5546 if (ResTy.isNull()) {
5548 diag::err_typecheck_cond_incompatible_operands) << LTy << RTy
5549 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5553 LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
5554 RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
5559 // -- The second and third operands have pointer type, or one has pointer
5560 // type and the other is a null pointer constant, or both are null
5561 // pointer constants, at least one of which is non-integral; pointer
5562 // conversions and qualification conversions are performed to bring them
5563 // to their composite pointer type. The result is of the composite
5565 // -- The second and third operands have pointer to member type, or one has
5566 // pointer to member type and the other is a null pointer constant;
5567 // pointer to member conversions and qualification conversions are
5568 // performed to bring them to a common type, whose cv-qualification
5569 // shall match the cv-qualification of either the second or the third
5570 // operand. The result is of the common type.
5571 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS);
5572 if (!Composite.isNull())
5575 // Similarly, attempt to find composite type of two objective-c pointers.
5576 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc);
5577 if (!Composite.isNull())
5580 // Check if we are using a null with a non-pointer type.
5581 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
5584 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
5585 << LHS.get()->getType() << RHS.get()->getType()
5586 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5590 static FunctionProtoType::ExceptionSpecInfo
5591 mergeExceptionSpecs(Sema &S, FunctionProtoType::ExceptionSpecInfo ESI1,
5592 FunctionProtoType::ExceptionSpecInfo ESI2,
5593 SmallVectorImpl<QualType> &ExceptionTypeStorage) {
5594 ExceptionSpecificationType EST1 = ESI1.Type;
5595 ExceptionSpecificationType EST2 = ESI2.Type;
5597 // If either of them can throw anything, that is the result.
5598 if (EST1 == EST_None) return ESI1;
5599 if (EST2 == EST_None) return ESI2;
5600 if (EST1 == EST_MSAny) return ESI1;
5601 if (EST2 == EST_MSAny) return ESI2;
5603 // If either of them is non-throwing, the result is the other.
5604 if (EST1 == EST_DynamicNone) return ESI2;
5605 if (EST2 == EST_DynamicNone) return ESI1;
5606 if (EST1 == EST_BasicNoexcept) return ESI2;
5607 if (EST2 == EST_BasicNoexcept) return ESI1;
5609 // If either of them is a non-value-dependent computed noexcept, that
5610 // determines the result.
5611 if (EST2 == EST_ComputedNoexcept && ESI2.NoexceptExpr &&
5612 !ESI2.NoexceptExpr->isValueDependent())
5613 return !ESI2.NoexceptExpr->EvaluateKnownConstInt(S.Context) ? ESI2 : ESI1;
5614 if (EST1 == EST_ComputedNoexcept && ESI1.NoexceptExpr &&
5615 !ESI1.NoexceptExpr->isValueDependent())
5616 return !ESI1.NoexceptExpr->EvaluateKnownConstInt(S.Context) ? ESI1 : ESI2;
5617 // If we're left with value-dependent computed noexcept expressions, we're
5618 // stuck. Before C++17, we can just drop the exception specification entirely,
5619 // since it's not actually part of the canonical type. And this should never
5620 // happen in C++17, because it would mean we were computing the composite
5621 // pointer type of dependent types, which should never happen.
5622 if (EST1 == EST_ComputedNoexcept || EST2 == EST_ComputedNoexcept) {
5623 assert(!S.getLangOpts().CPlusPlus1z &&
5624 "computing composite pointer type of dependent types");
5625 return FunctionProtoType::ExceptionSpecInfo();
5628 // Switch over the possibilities so that people adding new values know to
5629 // update this function.
5632 case EST_DynamicNone:
5634 case EST_BasicNoexcept:
5635 case EST_ComputedNoexcept:
5636 llvm_unreachable("handled above");
5639 // This is the fun case: both exception specifications are dynamic. Form
5640 // the union of the two lists.
5641 assert(EST2 == EST_Dynamic && "other cases should already be handled");
5642 llvm::SmallPtrSet<QualType, 8> Found;
5643 for (auto &Exceptions : {ESI1.Exceptions, ESI2.Exceptions})
5644 for (QualType E : Exceptions)
5645 if (Found.insert(S.Context.getCanonicalType(E)).second)
5646 ExceptionTypeStorage.push_back(E);
5648 FunctionProtoType::ExceptionSpecInfo Result(EST_Dynamic);
5649 Result.Exceptions = ExceptionTypeStorage;
5653 case EST_Unevaluated:
5654 case EST_Uninstantiated:
5656 llvm_unreachable("shouldn't see unresolved exception specifications here");
5659 llvm_unreachable("invalid ExceptionSpecificationType");
5662 /// \brief Find a merged pointer type and convert the two expressions to it.
5664 /// This finds the composite pointer type (or member pointer type) for @p E1
5665 /// and @p E2 according to C++1z 5p14. It converts both expressions to this
5666 /// type and returns it.
5667 /// It does not emit diagnostics.
5669 /// \param Loc The location of the operator requiring these two expressions to
5670 /// be converted to the composite pointer type.
5672 /// \param ConvertArgs If \c false, do not convert E1 and E2 to the target type.
5673 QualType Sema::FindCompositePointerType(SourceLocation Loc,
5674 Expr *&E1, Expr *&E2,
5676 assert(getLangOpts().CPlusPlus && "This function assumes C++");
5679 // The composite pointer type of two operands p1 and p2 having types T1
5681 QualType T1 = E1->getType(), T2 = E2->getType();
5683 // where at least one is a pointer or pointer to member type or
5684 // std::nullptr_t is:
5685 bool T1IsPointerLike = T1->isAnyPointerType() || T1->isMemberPointerType() ||
5686 T1->isNullPtrType();
5687 bool T2IsPointerLike = T2->isAnyPointerType() || T2->isMemberPointerType() ||
5688 T2->isNullPtrType();
5689 if (!T1IsPointerLike && !T2IsPointerLike)
5692 // - if both p1 and p2 are null pointer constants, std::nullptr_t;
5693 // This can't actually happen, following the standard, but we also use this
5694 // to implement the end of [expr.conv], which hits this case.
5696 // - if either p1 or p2 is a null pointer constant, T2 or T1, respectively;
5697 if (T1IsPointerLike &&
5698 E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5700 E2 = ImpCastExprToType(E2, T1, T1->isMemberPointerType()
5701 ? CK_NullToMemberPointer
5702 : CK_NullToPointer).get();
5705 if (T2IsPointerLike &&
5706 E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5708 E1 = ImpCastExprToType(E1, T2, T2->isMemberPointerType()
5709 ? CK_NullToMemberPointer
5710 : CK_NullToPointer).get();
5714 // Now both have to be pointers or member pointers.
5715 if (!T1IsPointerLike || !T2IsPointerLike)
5717 assert(!T1->isNullPtrType() && !T2->isNullPtrType() &&
5718 "nullptr_t should be a null pointer constant");
5720 // - if T1 or T2 is "pointer to cv1 void" and the other type is
5721 // "pointer to cv2 T", "pointer to cv12 void", where cv12 is
5722 // the union of cv1 and cv2;
5723 // - if T1 or T2 is "pointer to noexcept function" and the other type is
5724 // "pointer to function", where the function types are otherwise the same,
5725 // "pointer to function";
5726 // FIXME: This rule is defective: it should also permit removing noexcept
5727 // from a pointer to member function. As a Clang extension, we also
5728 // permit removing 'noreturn', so we generalize this rule to;
5729 // - [Clang] If T1 and T2 are both of type "pointer to function" or
5730 // "pointer to member function" and the pointee types can be unified
5731 // by a function pointer conversion, that conversion is applied
5732 // before checking the following rules.
5733 // - if T1 is "pointer to cv1 C1" and T2 is "pointer to cv2 C2", where C1
5734 // is reference-related to C2 or C2 is reference-related to C1 (8.6.3),
5735 // the cv-combined type of T1 and T2 or the cv-combined type of T2 and T1,
5737 // - if T1 is "pointer to member of C1 of type cv1 U1" and T2 is "pointer
5738 // to member of C2 of type cv2 U2" where C1 is reference-related to C2 or
5739 // C2 is reference-related to C1 (8.6.3), the cv-combined type of T2 and
5740 // T1 or the cv-combined type of T1 and T2, respectively;
5741 // - if T1 and T2 are similar types (4.5), the cv-combined type of T1 and
5744 // If looked at in the right way, these bullets all do the same thing.
5745 // What we do here is, we build the two possible cv-combined types, and try
5746 // the conversions in both directions. If only one works, or if the two
5747 // composite types are the same, we have succeeded.
5748 // FIXME: extended qualifiers?
5750 // Note that this will fail to find a composite pointer type for "pointer
5751 // to void" and "pointer to function". We can't actually perform the final
5752 // conversion in this case, even though a composite pointer type formally
5754 SmallVector<unsigned, 4> QualifierUnion;
5755 SmallVector<std::pair<const Type *, const Type *>, 4> MemberOfClass;
5756 QualType Composite1 = T1;
5757 QualType Composite2 = T2;
5758 unsigned NeedConstBefore = 0;
5760 const PointerType *Ptr1, *Ptr2;
5761 if ((Ptr1 = Composite1->getAs<PointerType>()) &&
5762 (Ptr2 = Composite2->getAs<PointerType>())) {
5763 Composite1 = Ptr1->getPointeeType();
5764 Composite2 = Ptr2->getPointeeType();
5766 // If we're allowed to create a non-standard composite type, keep track
5767 // of where we need to fill in additional 'const' qualifiers.
5768 if (Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
5769 NeedConstBefore = QualifierUnion.size();
5771 QualifierUnion.push_back(
5772 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
5773 MemberOfClass.push_back(std::make_pair(nullptr, nullptr));
5777 const MemberPointerType *MemPtr1, *MemPtr2;
5778 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) &&
5779 (MemPtr2 = Composite2->getAs<MemberPointerType>())) {
5780 Composite1 = MemPtr1->getPointeeType();
5781 Composite2 = MemPtr2->getPointeeType();
5783 // If we're allowed to create a non-standard composite type, keep track
5784 // of where we need to fill in additional 'const' qualifiers.
5785 if (Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
5786 NeedConstBefore = QualifierUnion.size();
5788 QualifierUnion.push_back(
5789 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
5790 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(),
5791 MemPtr2->getClass()));
5795 // FIXME: block pointer types?
5797 // Cannot unwrap any more types.
5801 // Apply the function pointer conversion to unify the types. We've already
5802 // unwrapped down to the function types, and we want to merge rather than
5803 // just convert, so do this ourselves rather than calling
5804 // IsFunctionConversion.
5806 // FIXME: In order to match the standard wording as closely as possible, we
5807 // currently only do this under a single level of pointers. Ideally, we would
5808 // allow this in general, and set NeedConstBefore to the relevant depth on
5809 // the side(s) where we changed anything.
5810 if (QualifierUnion.size() == 1) {
5811 if (auto *FPT1 = Composite1->getAs<FunctionProtoType>()) {
5812 if (auto *FPT2 = Composite2->getAs<FunctionProtoType>()) {
5813 FunctionProtoType::ExtProtoInfo EPI1 = FPT1->getExtProtoInfo();
5814 FunctionProtoType::ExtProtoInfo EPI2 = FPT2->getExtProtoInfo();
5816 // The result is noreturn if both operands are.
5818 EPI1.ExtInfo.getNoReturn() && EPI2.ExtInfo.getNoReturn();
5819 EPI1.ExtInfo = EPI1.ExtInfo.withNoReturn(Noreturn);
5820 EPI2.ExtInfo = EPI2.ExtInfo.withNoReturn(Noreturn);
5822 // The result is nothrow if both operands are.
5823 SmallVector<QualType, 8> ExceptionTypeStorage;
5824 EPI1.ExceptionSpec = EPI2.ExceptionSpec =
5825 mergeExceptionSpecs(*this, EPI1.ExceptionSpec, EPI2.ExceptionSpec,
5826 ExceptionTypeStorage);
5828 Composite1 = Context.getFunctionType(FPT1->getReturnType(),
5829 FPT1->getParamTypes(), EPI1);
5830 Composite2 = Context.getFunctionType(FPT2->getReturnType(),
5831 FPT2->getParamTypes(), EPI2);
5836 if (NeedConstBefore) {
5837 // Extension: Add 'const' to qualifiers that come before the first qualifier
5838 // mismatch, so that our (non-standard!) composite type meets the
5839 // requirements of C++ [conv.qual]p4 bullet 3.
5840 for (unsigned I = 0; I != NeedConstBefore; ++I)
5841 if ((QualifierUnion[I] & Qualifiers::Const) == 0)
5842 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const;
5845 // Rewrap the composites as pointers or member pointers with the union CVRs.
5846 auto MOC = MemberOfClass.rbegin();
5847 for (unsigned CVR : llvm::reverse(QualifierUnion)) {
5848 Qualifiers Quals = Qualifiers::fromCVRMask(CVR);
5849 auto Classes = *MOC++;
5850 if (Classes.first && Classes.second) {
5851 // Rebuild member pointer type
5852 Composite1 = Context.getMemberPointerType(
5853 Context.getQualifiedType(Composite1, Quals), Classes.first);
5854 Composite2 = Context.getMemberPointerType(
5855 Context.getQualifiedType(Composite2, Quals), Classes.second);
5857 // Rebuild pointer type
5859 Context.getPointerType(Context.getQualifiedType(Composite1, Quals));
5861 Context.getPointerType(Context.getQualifiedType(Composite2, Quals));
5869 InitializedEntity Entity;
5870 InitializationKind Kind;
5871 InitializationSequence E1ToC, E2ToC;
5874 Conversion(Sema &S, SourceLocation Loc, Expr *&E1, Expr *&E2,
5876 : S(S), E1(E1), E2(E2), Composite(Composite),
5877 Entity(InitializedEntity::InitializeTemporary(Composite)),
5878 Kind(InitializationKind::CreateCopy(Loc, SourceLocation())),
5879 E1ToC(S, Entity, Kind, E1), E2ToC(S, Entity, Kind, E2),
5880 Viable(E1ToC && E2ToC) {}
5883 ExprResult E1Result = E1ToC.Perform(S, Entity, Kind, E1);
5884 if (E1Result.isInvalid())
5886 E1 = E1Result.getAs<Expr>();
5888 ExprResult E2Result = E2ToC.Perform(S, Entity, Kind, E2);
5889 if (E2Result.isInvalid())
5891 E2 = E2Result.getAs<Expr>();
5897 // Try to convert to each composite pointer type.
5898 Conversion C1(*this, Loc, E1, E2, Composite1);
5899 if (C1.Viable && Context.hasSameType(Composite1, Composite2)) {
5900 if (ConvertArgs && C1.perform())
5902 return C1.Composite;
5904 Conversion C2(*this, Loc, E1, E2, Composite2);
5906 if (C1.Viable == C2.Viable) {
5907 // Either Composite1 and Composite2 are viable and are different, or
5908 // neither is viable.
5909 // FIXME: How both be viable and different?
5913 // Convert to the chosen type.
5914 if (ConvertArgs && (C1.Viable ? C1 : C2).perform())
5917 return C1.Viable ? C1.Composite : C2.Composite;
5920 ExprResult Sema::MaybeBindToTemporary(Expr *E) {
5924 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?");
5926 // If the result is a glvalue, we shouldn't bind it.
5930 // In ARC, calls that return a retainable type can return retained,
5931 // in which case we have to insert a consuming cast.
5932 if (getLangOpts().ObjCAutoRefCount &&
5933 E->getType()->isObjCRetainableType()) {
5935 bool ReturnsRetained;
5937 // For actual calls, we compute this by examining the type of the
5939 if (CallExpr *Call = dyn_cast<CallExpr>(E)) {
5940 Expr *Callee = Call->getCallee()->IgnoreParens();
5941 QualType T = Callee->getType();
5943 if (T == Context.BoundMemberTy) {
5944 // Handle pointer-to-members.
5945 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee))
5946 T = BinOp->getRHS()->getType();
5947 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee))
5948 T = Mem->getMemberDecl()->getType();
5951 if (const PointerType *Ptr = T->getAs<PointerType>())
5952 T = Ptr->getPointeeType();
5953 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>())
5954 T = Ptr->getPointeeType();
5955 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>())
5956 T = MemPtr->getPointeeType();
5958 const FunctionType *FTy = T->getAs<FunctionType>();
5959 assert(FTy && "call to value not of function type?");
5960 ReturnsRetained = FTy->getExtInfo().getProducesResult();
5962 // ActOnStmtExpr arranges things so that StmtExprs of retainable
5963 // type always produce a +1 object.
5964 } else if (isa<StmtExpr>(E)) {
5965 ReturnsRetained = true;
5967 // We hit this case with the lambda conversion-to-block optimization;
5968 // we don't want any extra casts here.
5969 } else if (isa<CastExpr>(E) &&
5970 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) {
5973 // For message sends and property references, we try to find an
5974 // actual method. FIXME: we should infer retention by selector in
5975 // cases where we don't have an actual method.
5977 ObjCMethodDecl *D = nullptr;
5978 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) {
5979 D = Send->getMethodDecl();
5980 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) {
5981 D = BoxedExpr->getBoxingMethod();
5982 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) {
5983 // Don't do reclaims if we're using the zero-element array
5985 if (ArrayLit->getNumElements() == 0 &&
5986 Context.getLangOpts().ObjCRuntime.hasEmptyCollections())
5989 D = ArrayLit->getArrayWithObjectsMethod();
5990 } else if (ObjCDictionaryLiteral *DictLit
5991 = dyn_cast<ObjCDictionaryLiteral>(E)) {
5992 // Don't do reclaims if we're using the zero-element dictionary
5994 if (DictLit->getNumElements() == 0 &&
5995 Context.getLangOpts().ObjCRuntime.hasEmptyCollections())
5998 D = DictLit->getDictWithObjectsMethod();
6001 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>());
6003 // Don't do reclaims on performSelector calls; despite their
6004 // return type, the invoked method doesn't necessarily actually
6005 // return an object.
6006 if (!ReturnsRetained &&
6007 D && D->getMethodFamily() == OMF_performSelector)
6011 // Don't reclaim an object of Class type.
6012 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType())
6015 Cleanup.setExprNeedsCleanups(true);
6017 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject
6018 : CK_ARCReclaimReturnedObject);
6019 return ImplicitCastExpr::Create(Context, E->getType(), ck, E, nullptr,
6023 if (!getLangOpts().CPlusPlus)
6026 // Search for the base element type (cf. ASTContext::getBaseElementType) with
6027 // a fast path for the common case that the type is directly a RecordType.
6028 const Type *T = Context.getCanonicalType(E->getType().getTypePtr());
6029 const RecordType *RT = nullptr;
6031 switch (T->getTypeClass()) {
6033 RT = cast<RecordType>(T);
6035 case Type::ConstantArray:
6036 case Type::IncompleteArray:
6037 case Type::VariableArray:
6038 case Type::DependentSizedArray:
6039 T = cast<ArrayType>(T)->getElementType().getTypePtr();
6046 // That should be enough to guarantee that this type is complete, if we're
6047 // not processing a decltype expression.
6048 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
6049 if (RD->isInvalidDecl() || RD->isDependentContext())
6052 bool IsDecltype = ExprEvalContexts.back().IsDecltype;
6053 CXXDestructorDecl *Destructor = IsDecltype ? nullptr : LookupDestructor(RD);
6056 MarkFunctionReferenced(E->getExprLoc(), Destructor);
6057 CheckDestructorAccess(E->getExprLoc(), Destructor,
6058 PDiag(diag::err_access_dtor_temp)
6060 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
6063 // If destructor is trivial, we can avoid the extra copy.
6064 if (Destructor->isTrivial())
6067 // We need a cleanup, but we don't need to remember the temporary.
6068 Cleanup.setExprNeedsCleanups(true);
6071 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor);
6072 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E);
6075 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind);
6081 Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) {
6082 if (SubExpr.isInvalid())
6085 return MaybeCreateExprWithCleanups(SubExpr.get());
6088 Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) {
6089 assert(SubExpr && "subexpression can't be null!");
6091 CleanupVarDeclMarking();
6093 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects;
6094 assert(ExprCleanupObjects.size() >= FirstCleanup);
6095 assert(Cleanup.exprNeedsCleanups() ||
6096 ExprCleanupObjects.size() == FirstCleanup);
6097 if (!Cleanup.exprNeedsCleanups())
6100 auto Cleanups = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup,
6101 ExprCleanupObjects.size() - FirstCleanup);
6103 auto *E = ExprWithCleanups::Create(
6104 Context, SubExpr, Cleanup.cleanupsHaveSideEffects(), Cleanups);
6105 DiscardCleanupsInEvaluationContext();
6110 Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) {
6111 assert(SubStmt && "sub-statement can't be null!");
6113 CleanupVarDeclMarking();
6115 if (!Cleanup.exprNeedsCleanups())
6118 // FIXME: In order to attach the temporaries, wrap the statement into
6119 // a StmtExpr; currently this is only used for asm statements.
6120 // This is hacky, either create a new CXXStmtWithTemporaries statement or
6121 // a new AsmStmtWithTemporaries.
6122 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, SubStmt,
6125 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(),
6127 return MaybeCreateExprWithCleanups(E);
6130 /// Process the expression contained within a decltype. For such expressions,
6131 /// certain semantic checks on temporaries are delayed until this point, and
6132 /// are omitted for the 'topmost' call in the decltype expression. If the
6133 /// topmost call bound a temporary, strip that temporary off the expression.
6134 ExprResult Sema::ActOnDecltypeExpression(Expr *E) {
6135 assert(ExprEvalContexts.back().IsDecltype && "not in a decltype expression");
6137 // C++11 [expr.call]p11:
6138 // If a function call is a prvalue of object type,
6139 // -- if the function call is either
6140 // -- the operand of a decltype-specifier, or
6141 // -- the right operand of a comma operator that is the operand of a
6142 // decltype-specifier,
6143 // a temporary object is not introduced for the prvalue.
6145 // Recursively rebuild ParenExprs and comma expressions to strip out the
6146 // outermost CXXBindTemporaryExpr, if any.
6147 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
6148 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr());
6149 if (SubExpr.isInvalid())
6151 if (SubExpr.get() == PE->getSubExpr())
6153 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.get());
6155 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
6156 if (BO->getOpcode() == BO_Comma) {
6157 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS());
6158 if (RHS.isInvalid())
6160 if (RHS.get() == BO->getRHS())
6162 return new (Context) BinaryOperator(
6163 BO->getLHS(), RHS.get(), BO_Comma, BO->getType(), BO->getValueKind(),
6164 BO->getObjectKind(), BO->getOperatorLoc(), BO->getFPFeatures());
6168 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E);
6169 CallExpr *TopCall = TopBind ? dyn_cast<CallExpr>(TopBind->getSubExpr())
6176 // Disable the special decltype handling now.
6177 ExprEvalContexts.back().IsDecltype = false;
6179 // In MS mode, don't perform any extra checking of call return types within a
6180 // decltype expression.
6181 if (getLangOpts().MSVCCompat)
6184 // Perform the semantic checks we delayed until this point.
6185 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size();
6187 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I];
6188 if (Call == TopCall)
6191 if (CheckCallReturnType(Call->getCallReturnType(Context),
6192 Call->getLocStart(),
6193 Call, Call->getDirectCallee()))
6197 // Now all relevant types are complete, check the destructors are accessible
6198 // and non-deleted, and annotate them on the temporaries.
6199 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size();
6201 CXXBindTemporaryExpr *Bind =
6202 ExprEvalContexts.back().DelayedDecltypeBinds[I];
6203 if (Bind == TopBind)
6206 CXXTemporary *Temp = Bind->getTemporary();
6209 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
6210 CXXDestructorDecl *Destructor = LookupDestructor(RD);
6211 Temp->setDestructor(Destructor);
6213 MarkFunctionReferenced(Bind->getExprLoc(), Destructor);
6214 CheckDestructorAccess(Bind->getExprLoc(), Destructor,
6215 PDiag(diag::err_access_dtor_temp)
6216 << Bind->getType());
6217 if (DiagnoseUseOfDecl(Destructor, Bind->getExprLoc()))
6220 // We need a cleanup, but we don't need to remember the temporary.
6221 Cleanup.setExprNeedsCleanups(true);
6224 // Possibly strip off the top CXXBindTemporaryExpr.
6228 /// Note a set of 'operator->' functions that were used for a member access.
6229 static void noteOperatorArrows(Sema &S,
6230 ArrayRef<FunctionDecl *> OperatorArrows) {
6231 unsigned SkipStart = OperatorArrows.size(), SkipCount = 0;
6232 // FIXME: Make this configurable?
6234 if (OperatorArrows.size() > Limit) {
6235 // Produce Limit-1 normal notes and one 'skipping' note.
6236 SkipStart = (Limit - 1) / 2 + (Limit - 1) % 2;
6237 SkipCount = OperatorArrows.size() - (Limit - 1);
6240 for (unsigned I = 0; I < OperatorArrows.size(); /**/) {
6241 if (I == SkipStart) {
6242 S.Diag(OperatorArrows[I]->getLocation(),
6243 diag::note_operator_arrows_suppressed)
6247 S.Diag(OperatorArrows[I]->getLocation(), diag::note_operator_arrow_here)
6248 << OperatorArrows[I]->getCallResultType();
6254 ExprResult Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base,
6255 SourceLocation OpLoc,
6256 tok::TokenKind OpKind,
6257 ParsedType &ObjectType,
6258 bool &MayBePseudoDestructor) {
6259 // Since this might be a postfix expression, get rid of ParenListExprs.
6260 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base);
6261 if (Result.isInvalid()) return ExprError();
6262 Base = Result.get();
6264 Result = CheckPlaceholderExpr(Base);
6265 if (Result.isInvalid()) return ExprError();
6266 Base = Result.get();
6268 QualType BaseType = Base->getType();
6269 MayBePseudoDestructor = false;
6270 if (BaseType->isDependentType()) {
6271 // If we have a pointer to a dependent type and are using the -> operator,
6272 // the object type is the type that the pointer points to. We might still
6273 // have enough information about that type to do something useful.
6274 if (OpKind == tok::arrow)
6275 if (const PointerType *Ptr = BaseType->getAs<PointerType>())
6276 BaseType = Ptr->getPointeeType();
6278 ObjectType = ParsedType::make(BaseType);
6279 MayBePseudoDestructor = true;
6283 // C++ [over.match.oper]p8:
6284 // [...] When operator->returns, the operator-> is applied to the value
6285 // returned, with the original second operand.
6286 if (OpKind == tok::arrow) {
6287 QualType StartingType = BaseType;
6288 bool NoArrowOperatorFound = false;
6289 bool FirstIteration = true;
6290 FunctionDecl *CurFD = dyn_cast<FunctionDecl>(CurContext);
6291 // The set of types we've considered so far.
6292 llvm::SmallPtrSet<CanQualType,8> CTypes;
6293 SmallVector<FunctionDecl*, 8> OperatorArrows;
6294 CTypes.insert(Context.getCanonicalType(BaseType));
6296 while (BaseType->isRecordType()) {
6297 if (OperatorArrows.size() >= getLangOpts().ArrowDepth) {
6298 Diag(OpLoc, diag::err_operator_arrow_depth_exceeded)
6299 << StartingType << getLangOpts().ArrowDepth << Base->getSourceRange();
6300 noteOperatorArrows(*this, OperatorArrows);
6301 Diag(OpLoc, diag::note_operator_arrow_depth)
6302 << getLangOpts().ArrowDepth;
6306 Result = BuildOverloadedArrowExpr(
6308 // When in a template specialization and on the first loop iteration,
6309 // potentially give the default diagnostic (with the fixit in a
6310 // separate note) instead of having the error reported back to here
6311 // and giving a diagnostic with a fixit attached to the error itself.
6312 (FirstIteration && CurFD && CurFD->isFunctionTemplateSpecialization())
6314 : &NoArrowOperatorFound);
6315 if (Result.isInvalid()) {
6316 if (NoArrowOperatorFound) {
6317 if (FirstIteration) {
6318 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
6319 << BaseType << 1 << Base->getSourceRange()
6320 << FixItHint::CreateReplacement(OpLoc, ".");
6321 OpKind = tok::period;
6324 Diag(OpLoc, diag::err_typecheck_member_reference_arrow)
6325 << BaseType << Base->getSourceRange();
6326 CallExpr *CE = dyn_cast<CallExpr>(Base);
6327 if (Decl *CD = (CE ? CE->getCalleeDecl() : nullptr)) {
6328 Diag(CD->getLocStart(),
6329 diag::note_member_reference_arrow_from_operator_arrow);
6334 Base = Result.get();
6335 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base))
6336 OperatorArrows.push_back(OpCall->getDirectCallee());
6337 BaseType = Base->getType();
6338 CanQualType CBaseType = Context.getCanonicalType(BaseType);
6339 if (!CTypes.insert(CBaseType).second) {
6340 Diag(OpLoc, diag::err_operator_arrow_circular) << StartingType;
6341 noteOperatorArrows(*this, OperatorArrows);
6344 FirstIteration = false;
6347 if (OpKind == tok::arrow &&
6348 (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()))
6349 BaseType = BaseType->getPointeeType();
6352 // Objective-C properties allow "." access on Objective-C pointer types,
6353 // so adjust the base type to the object type itself.
6354 if (BaseType->isObjCObjectPointerType())
6355 BaseType = BaseType->getPointeeType();
6357 // C++ [basic.lookup.classref]p2:
6358 // [...] If the type of the object expression is of pointer to scalar
6359 // type, the unqualified-id is looked up in the context of the complete
6360 // postfix-expression.
6362 // This also indicates that we could be parsing a pseudo-destructor-name.
6363 // Note that Objective-C class and object types can be pseudo-destructor
6364 // expressions or normal member (ivar or property) access expressions, and
6365 // it's legal for the type to be incomplete if this is a pseudo-destructor
6366 // call. We'll do more incomplete-type checks later in the lookup process,
6367 // so just skip this check for ObjC types.
6368 if (BaseType->isObjCObjectOrInterfaceType()) {
6369 ObjectType = ParsedType::make(BaseType);
6370 MayBePseudoDestructor = true;
6372 } else if (!BaseType->isRecordType()) {
6373 ObjectType = nullptr;
6374 MayBePseudoDestructor = true;
6378 // The object type must be complete (or dependent), or
6379 // C++11 [expr.prim.general]p3:
6380 // Unlike the object expression in other contexts, *this is not required to
6381 // be of complete type for purposes of class member access (5.2.5) outside
6382 // the member function body.
6383 if (!BaseType->isDependentType() &&
6384 !isThisOutsideMemberFunctionBody(BaseType) &&
6385 RequireCompleteType(OpLoc, BaseType, diag::err_incomplete_member_access))
6388 // C++ [basic.lookup.classref]p2:
6389 // If the id-expression in a class member access (5.2.5) is an
6390 // unqualified-id, and the type of the object expression is of a class
6391 // type C (or of pointer to a class type C), the unqualified-id is looked
6392 // up in the scope of class C. [...]
6393 ObjectType = ParsedType::make(BaseType);
6397 static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base,
6398 tok::TokenKind& OpKind, SourceLocation OpLoc) {
6399 if (Base->hasPlaceholderType()) {
6400 ExprResult result = S.CheckPlaceholderExpr(Base);
6401 if (result.isInvalid()) return true;
6402 Base = result.get();
6404 ObjectType = Base->getType();
6406 // C++ [expr.pseudo]p2:
6407 // The left-hand side of the dot operator shall be of scalar type. The
6408 // left-hand side of the arrow operator shall be of pointer to scalar type.
6409 // This scalar type is the object type.
6410 // Note that this is rather different from the normal handling for the
6412 if (OpKind == tok::arrow) {
6413 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) {
6414 ObjectType = Ptr->getPointeeType();
6415 } else if (!Base->isTypeDependent()) {
6416 // The user wrote "p->" when they probably meant "p."; fix it.
6417 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
6418 << ObjectType << true
6419 << FixItHint::CreateReplacement(OpLoc, ".");
6420 if (S.isSFINAEContext())
6423 OpKind = tok::period;
6430 /// \brief Check if it's ok to try and recover dot pseudo destructor calls on
6431 /// pointer objects.
6433 canRecoverDotPseudoDestructorCallsOnPointerObjects(Sema &SemaRef,
6434 QualType DestructedType) {
6435 // If this is a record type, check if its destructor is callable.
6436 if (auto *RD = DestructedType->getAsCXXRecordDecl()) {
6437 if (CXXDestructorDecl *D = SemaRef.LookupDestructor(RD))
6438 return SemaRef.CanUseDecl(D, /*TreatUnavailableAsInvalid=*/false);
6442 // Otherwise, check if it's a type for which it's valid to use a pseudo-dtor.
6443 return DestructedType->isDependentType() || DestructedType->isScalarType() ||
6444 DestructedType->isVectorType();
6447 ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base,
6448 SourceLocation OpLoc,
6449 tok::TokenKind OpKind,
6450 const CXXScopeSpec &SS,
6451 TypeSourceInfo *ScopeTypeInfo,
6452 SourceLocation CCLoc,
6453 SourceLocation TildeLoc,
6454 PseudoDestructorTypeStorage Destructed) {
6455 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo();
6457 QualType ObjectType;
6458 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6461 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() &&
6462 !ObjectType->isVectorType()) {
6463 if (getLangOpts().MSVCCompat && ObjectType->isVoidType())
6464 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange();
6466 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar)
6467 << ObjectType << Base->getSourceRange();
6472 // C++ [expr.pseudo]p2:
6473 // [...] The cv-unqualified versions of the object type and of the type
6474 // designated by the pseudo-destructor-name shall be the same type.
6475 if (DestructedTypeInfo) {
6476 QualType DestructedType = DestructedTypeInfo->getType();
6477 SourceLocation DestructedTypeStart
6478 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin();
6479 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) {
6480 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) {
6481 // Detect dot pseudo destructor calls on pointer objects, e.g.:
6484 if (OpKind == tok::period && ObjectType->isPointerType() &&
6485 Context.hasSameUnqualifiedType(DestructedType,
6486 ObjectType->getPointeeType())) {
6488 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
6489 << ObjectType << /*IsArrow=*/0 << Base->getSourceRange();
6491 // Issue a fixit only when the destructor is valid.
6492 if (canRecoverDotPseudoDestructorCallsOnPointerObjects(
6493 *this, DestructedType))
6494 Diagnostic << FixItHint::CreateReplacement(OpLoc, "->");
6496 // Recover by setting the object type to the destructed type and the
6497 // operator to '->'.
6498 ObjectType = DestructedType;
6499 OpKind = tok::arrow;
6501 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch)
6502 << ObjectType << DestructedType << Base->getSourceRange()
6503 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
6505 // Recover by setting the destructed type to the object type.
6506 DestructedType = ObjectType;
6507 DestructedTypeInfo =
6508 Context.getTrivialTypeSourceInfo(ObjectType, DestructedTypeStart);
6509 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6511 } else if (DestructedType.getObjCLifetime() !=
6512 ObjectType.getObjCLifetime()) {
6514 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) {
6515 // Okay: just pretend that the user provided the correctly-qualified
6518 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals)
6519 << ObjectType << DestructedType << Base->getSourceRange()
6520 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
6523 // Recover by setting the destructed type to the object type.
6524 DestructedType = ObjectType;
6525 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType,
6526 DestructedTypeStart);
6527 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6532 // C++ [expr.pseudo]p2:
6533 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the
6536 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name
6538 // shall designate the same scalar type.
6539 if (ScopeTypeInfo) {
6540 QualType ScopeType = ScopeTypeInfo->getType();
6541 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() &&
6542 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) {
6544 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(),
6545 diag::err_pseudo_dtor_type_mismatch)
6546 << ObjectType << ScopeType << Base->getSourceRange()
6547 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange();
6549 ScopeType = QualType();
6550 ScopeTypeInfo = nullptr;
6555 = new (Context) CXXPseudoDestructorExpr(Context, Base,
6556 OpKind == tok::arrow, OpLoc,
6557 SS.getWithLocInContext(Context),
6566 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
6567 SourceLocation OpLoc,
6568 tok::TokenKind OpKind,
6570 UnqualifiedId &FirstTypeName,
6571 SourceLocation CCLoc,
6572 SourceLocation TildeLoc,
6573 UnqualifiedId &SecondTypeName) {
6574 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
6575 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
6576 "Invalid first type name in pseudo-destructor");
6577 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
6578 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
6579 "Invalid second type name in pseudo-destructor");
6581 QualType ObjectType;
6582 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6585 // Compute the object type that we should use for name lookup purposes. Only
6586 // record types and dependent types matter.
6587 ParsedType ObjectTypePtrForLookup;
6589 if (ObjectType->isRecordType())
6590 ObjectTypePtrForLookup = ParsedType::make(ObjectType);
6591 else if (ObjectType->isDependentType())
6592 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy);
6595 // Convert the name of the type being destructed (following the ~) into a
6596 // type (with source-location information).
6597 QualType DestructedType;
6598 TypeSourceInfo *DestructedTypeInfo = nullptr;
6599 PseudoDestructorTypeStorage Destructed;
6600 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) {
6601 ParsedType T = getTypeName(*SecondTypeName.Identifier,
6602 SecondTypeName.StartLocation,
6603 S, &SS, true, false, ObjectTypePtrForLookup,
6604 /*IsCtorOrDtorName*/true);
6606 ((SS.isSet() && !computeDeclContext(SS, false)) ||
6607 (!SS.isSet() && ObjectType->isDependentType()))) {
6608 // The name of the type being destroyed is a dependent name, and we
6609 // couldn't find anything useful in scope. Just store the identifier and
6610 // it's location, and we'll perform (qualified) name lookup again at
6611 // template instantiation time.
6612 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier,
6613 SecondTypeName.StartLocation);
6615 Diag(SecondTypeName.StartLocation,
6616 diag::err_pseudo_dtor_destructor_non_type)
6617 << SecondTypeName.Identifier << ObjectType;
6618 if (isSFINAEContext())
6621 // Recover by assuming we had the right type all along.
6622 DestructedType = ObjectType;
6624 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo);
6626 // Resolve the template-id to a type.
6627 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId;
6628 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
6629 TemplateId->NumArgs);
6630 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
6631 TemplateId->TemplateKWLoc,
6632 TemplateId->Template,
6634 TemplateId->TemplateNameLoc,
6635 TemplateId->LAngleLoc,
6637 TemplateId->RAngleLoc,
6638 /*IsCtorOrDtorName*/true);
6639 if (T.isInvalid() || !T.get()) {
6640 // Recover by assuming we had the right type all along.
6641 DestructedType = ObjectType;
6643 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo);
6646 // If we've performed some kind of recovery, (re-)build the type source
6648 if (!DestructedType.isNull()) {
6649 if (!DestructedTypeInfo)
6650 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType,
6651 SecondTypeName.StartLocation);
6652 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6655 // Convert the name of the scope type (the type prior to '::') into a type.
6656 TypeSourceInfo *ScopeTypeInfo = nullptr;
6658 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
6659 FirstTypeName.Identifier) {
6660 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) {
6661 ParsedType T = getTypeName(*FirstTypeName.Identifier,
6662 FirstTypeName.StartLocation,
6663 S, &SS, true, false, ObjectTypePtrForLookup,
6664 /*IsCtorOrDtorName*/true);
6666 Diag(FirstTypeName.StartLocation,
6667 diag::err_pseudo_dtor_destructor_non_type)
6668 << FirstTypeName.Identifier << ObjectType;
6670 if (isSFINAEContext())
6673 // Just drop this type. It's unnecessary anyway.
6674 ScopeType = QualType();
6676 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo);
6678 // Resolve the template-id to a type.
6679 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId;
6680 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
6681 TemplateId->NumArgs);
6682 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
6683 TemplateId->TemplateKWLoc,
6684 TemplateId->Template,
6686 TemplateId->TemplateNameLoc,
6687 TemplateId->LAngleLoc,
6689 TemplateId->RAngleLoc,
6690 /*IsCtorOrDtorName*/true);
6691 if (T.isInvalid() || !T.get()) {
6692 // Recover by dropping this type.
6693 ScopeType = QualType();
6695 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo);
6699 if (!ScopeType.isNull() && !ScopeTypeInfo)
6700 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType,
6701 FirstTypeName.StartLocation);
6704 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS,
6705 ScopeTypeInfo, CCLoc, TildeLoc,
6709 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
6710 SourceLocation OpLoc,
6711 tok::TokenKind OpKind,
6712 SourceLocation TildeLoc,
6713 const DeclSpec& DS) {
6714 QualType ObjectType;
6715 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6718 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc(),
6722 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T);
6723 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc());
6724 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T);
6725 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo);
6727 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(),
6728 nullptr, SourceLocation(), TildeLoc,
6732 ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl,
6733 CXXConversionDecl *Method,
6734 bool HadMultipleCandidates) {
6735 if (Method->getParent()->isLambda() &&
6736 Method->getConversionType()->isBlockPointerType()) {
6737 // This is a lambda coversion to block pointer; check if the argument
6740 CastExpr *CE = dyn_cast<CastExpr>(SubE);
6741 if (CE && CE->getCastKind() == CK_NoOp)
6742 SubE = CE->getSubExpr();
6743 SubE = SubE->IgnoreParens();
6744 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE))
6745 SubE = BE->getSubExpr();
6746 if (isa<LambdaExpr>(SubE)) {
6747 // For the conversion to block pointer on a lambda expression, we
6748 // construct a special BlockLiteral instead; this doesn't really make
6749 // a difference in ARC, but outside of ARC the resulting block literal
6750 // follows the normal lifetime rules for block literals instead of being
6752 DiagnosticErrorTrap Trap(Diags);
6753 PushExpressionEvaluationContext(
6754 ExpressionEvaluationContext::PotentiallyEvaluated);
6755 ExprResult Exp = BuildBlockForLambdaConversion(E->getExprLoc(),
6758 PopExpressionEvaluationContext();
6760 if (Exp.isInvalid())
6761 Diag(E->getExprLoc(), diag::note_lambda_to_block_conv);
6766 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/nullptr,
6768 if (Exp.isInvalid())
6771 MemberExpr *ME = new (Context) MemberExpr(
6772 Exp.get(), /*IsArrow=*/false, SourceLocation(), Method, SourceLocation(),
6773 Context.BoundMemberTy, VK_RValue, OK_Ordinary);
6774 if (HadMultipleCandidates)
6775 ME->setHadMultipleCandidates(true);
6776 MarkMemberReferenced(ME);
6778 QualType ResultType = Method->getReturnType();
6779 ExprValueKind VK = Expr::getValueKindForType(ResultType);
6780 ResultType = ResultType.getNonLValueExprType(Context);
6782 CXXMemberCallExpr *CE =
6783 new (Context) CXXMemberCallExpr(Context, ME, None, ResultType, VK,
6784 Exp.get()->getLocEnd());
6786 if (CheckFunctionCall(Method, CE,
6787 Method->getType()->castAs<FunctionProtoType>()))
6793 ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand,
6794 SourceLocation RParen) {
6795 // If the operand is an unresolved lookup expression, the expression is ill-
6796 // formed per [over.over]p1, because overloaded function names cannot be used
6797 // without arguments except in explicit contexts.
6798 ExprResult R = CheckPlaceholderExpr(Operand);
6802 // The operand may have been modified when checking the placeholder type.
6805 if (!inTemplateInstantiation() && Operand->HasSideEffects(Context, false)) {
6806 // The expression operand for noexcept is in an unevaluated expression
6807 // context, so side effects could result in unintended consequences.
6808 Diag(Operand->getExprLoc(), diag::warn_side_effects_unevaluated_context);
6811 CanThrowResult CanThrow = canThrow(Operand);
6812 return new (Context)
6813 CXXNoexceptExpr(Context.BoolTy, Operand, CanThrow, KeyLoc, RParen);
6816 ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation,
6817 Expr *Operand, SourceLocation RParen) {
6818 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen);
6821 static bool IsSpecialDiscardedValue(Expr *E) {
6822 // In C++11, discarded-value expressions of a certain form are special,
6823 // according to [expr]p10:
6824 // The lvalue-to-rvalue conversion (4.1) is applied only if the
6825 // expression is an lvalue of volatile-qualified type and it has
6826 // one of the following forms:
6827 E = E->IgnoreParens();
6829 // - id-expression (5.1.1),
6830 if (isa<DeclRefExpr>(E))
6833 // - subscripting (5.2.1),
6834 if (isa<ArraySubscriptExpr>(E))
6837 // - class member access (5.2.5),
6838 if (isa<MemberExpr>(E))
6841 // - indirection (5.3.1),
6842 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E))
6843 if (UO->getOpcode() == UO_Deref)
6846 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
6847 // - pointer-to-member operation (5.5),
6848 if (BO->isPtrMemOp())
6851 // - comma expression (5.18) where the right operand is one of the above.
6852 if (BO->getOpcode() == BO_Comma)
6853 return IsSpecialDiscardedValue(BO->getRHS());
6856 // - conditional expression (5.16) where both the second and the third
6857 // operands are one of the above, or
6858 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E))
6859 return IsSpecialDiscardedValue(CO->getTrueExpr()) &&
6860 IsSpecialDiscardedValue(CO->getFalseExpr());
6861 // The related edge case of "*x ?: *x".
6862 if (BinaryConditionalOperator *BCO =
6863 dyn_cast<BinaryConditionalOperator>(E)) {
6864 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(BCO->getTrueExpr()))
6865 return IsSpecialDiscardedValue(OVE->getSourceExpr()) &&
6866 IsSpecialDiscardedValue(BCO->getFalseExpr());
6869 // Objective-C++ extensions to the rule.
6870 if (isa<PseudoObjectExpr>(E) || isa<ObjCIvarRefExpr>(E))
6876 /// Perform the conversions required for an expression used in a
6877 /// context that ignores the result.
6878 ExprResult Sema::IgnoredValueConversions(Expr *E) {
6879 if (E->hasPlaceholderType()) {
6880 ExprResult result = CheckPlaceholderExpr(E);
6881 if (result.isInvalid()) return E;
6886 // [Except in specific positions,] an lvalue that does not have
6887 // array type is converted to the value stored in the
6888 // designated object (and is no longer an lvalue).
6889 if (E->isRValue()) {
6890 // In C, function designators (i.e. expressions of function type)
6891 // are r-values, but we still want to do function-to-pointer decay
6892 // on them. This is both technically correct and convenient for
6894 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType())
6895 return DefaultFunctionArrayConversion(E);
6900 if (getLangOpts().CPlusPlus) {
6901 // The C++11 standard defines the notion of a discarded-value expression;
6902 // normally, we don't need to do anything to handle it, but if it is a
6903 // volatile lvalue with a special form, we perform an lvalue-to-rvalue
6905 if (getLangOpts().CPlusPlus11 && E->isGLValue() &&
6906 E->getType().isVolatileQualified() &&
6907 IsSpecialDiscardedValue(E)) {
6908 ExprResult Res = DefaultLvalueConversion(E);
6909 if (Res.isInvalid())
6915 // If the expression is a prvalue after this optional conversion, the
6916 // temporary materialization conversion is applied.
6918 // We skip this step: IR generation is able to synthesize the storage for
6919 // itself in the aggregate case, and adding the extra node to the AST is
6921 // FIXME: We don't emit lifetime markers for the temporaries due to this.
6922 // FIXME: Do any other AST consumers care about this?
6926 // GCC seems to also exclude expressions of incomplete enum type.
6927 if (const EnumType *T = E->getType()->getAs<EnumType>()) {
6928 if (!T->getDecl()->isComplete()) {
6929 // FIXME: stupid workaround for a codegen bug!
6930 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).get();
6935 ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
6936 if (Res.isInvalid())
6940 if (!E->getType()->isVoidType())
6941 RequireCompleteType(E->getExprLoc(), E->getType(),
6942 diag::err_incomplete_type);
6946 // If we can unambiguously determine whether Var can never be used
6947 // in a constant expression, return true.
6948 // - if the variable and its initializer are non-dependent, then
6949 // we can unambiguously check if the variable is a constant expression.
6950 // - if the initializer is not value dependent - we can determine whether
6951 // it can be used to initialize a constant expression. If Init can not
6952 // be used to initialize a constant expression we conclude that Var can
6953 // never be a constant expression.
6954 // - FXIME: if the initializer is dependent, we can still do some analysis and
6955 // identify certain cases unambiguously as non-const by using a Visitor:
6956 // - such as those that involve odr-use of a ParmVarDecl, involve a new
6957 // delete, lambda-expr, dynamic-cast, reinterpret-cast etc...
6958 static inline bool VariableCanNeverBeAConstantExpression(VarDecl *Var,
6959 ASTContext &Context) {
6960 if (isa<ParmVarDecl>(Var)) return true;
6961 const VarDecl *DefVD = nullptr;
6963 // If there is no initializer - this can not be a constant expression.
6964 if (!Var->getAnyInitializer(DefVD)) return true;
6966 if (DefVD->isWeak()) return false;
6967 EvaluatedStmt *Eval = DefVD->ensureEvaluatedStmt();
6969 Expr *Init = cast<Expr>(Eval->Value);
6971 if (Var->getType()->isDependentType() || Init->isValueDependent()) {
6972 // FIXME: Teach the constant evaluator to deal with the non-dependent parts
6973 // of value-dependent expressions, and use it here to determine whether the
6974 // initializer is a potential constant expression.
6978 return !IsVariableAConstantExpression(Var, Context);
6981 /// \brief Check if the current lambda has any potential captures
6982 /// that must be captured by any of its enclosing lambdas that are ready to
6983 /// capture. If there is a lambda that can capture a nested
6984 /// potential-capture, go ahead and do so. Also, check to see if any
6985 /// variables are uncaptureable or do not involve an odr-use so do not
6986 /// need to be captured.
6988 static void CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(
6989 Expr *const FE, LambdaScopeInfo *const CurrentLSI, Sema &S) {
6991 assert(!S.isUnevaluatedContext());
6992 assert(S.CurContext->isDependentContext());
6994 DeclContext *DC = S.CurContext;
6995 while (DC && isa<CapturedDecl>(DC))
6996 DC = DC->getParent();
6998 CurrentLSI->CallOperator == DC &&
6999 "The current call operator must be synchronized with Sema's CurContext");
7002 const bool IsFullExprInstantiationDependent = FE->isInstantiationDependent();
7004 ArrayRef<const FunctionScopeInfo *> FunctionScopesArrayRef(
7005 S.FunctionScopes.data(), S.FunctionScopes.size());
7007 // All the potentially captureable variables in the current nested
7008 // lambda (within a generic outer lambda), must be captured by an
7009 // outer lambda that is enclosed within a non-dependent context.
7010 const unsigned NumPotentialCaptures =
7011 CurrentLSI->getNumPotentialVariableCaptures();
7012 for (unsigned I = 0; I != NumPotentialCaptures; ++I) {
7013 Expr *VarExpr = nullptr;
7014 VarDecl *Var = nullptr;
7015 CurrentLSI->getPotentialVariableCapture(I, Var, VarExpr);
7016 // If the variable is clearly identified as non-odr-used and the full
7017 // expression is not instantiation dependent, only then do we not
7018 // need to check enclosing lambda's for speculative captures.
7020 // Even though 'x' is not odr-used, it should be captured.
7022 // const int x = 10;
7023 // auto L = [=](auto a) {
7027 if (CurrentLSI->isVariableExprMarkedAsNonODRUsed(VarExpr) &&
7028 !IsFullExprInstantiationDependent)
7031 // If we have a capture-capable lambda for the variable, go ahead and
7032 // capture the variable in that lambda (and all its enclosing lambdas).
7033 if (const Optional<unsigned> Index =
7034 getStackIndexOfNearestEnclosingCaptureCapableLambda(
7035 FunctionScopesArrayRef, Var, S)) {
7036 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
7037 MarkVarDeclODRUsed(Var, VarExpr->getExprLoc(), S,
7038 &FunctionScopeIndexOfCapturableLambda);
7040 const bool IsVarNeverAConstantExpression =
7041 VariableCanNeverBeAConstantExpression(Var, S.Context);
7042 if (!IsFullExprInstantiationDependent || IsVarNeverAConstantExpression) {
7043 // This full expression is not instantiation dependent or the variable
7044 // can not be used in a constant expression - which means
7045 // this variable must be odr-used here, so diagnose a
7046 // capture violation early, if the variable is un-captureable.
7047 // This is purely for diagnosing errors early. Otherwise, this
7048 // error would get diagnosed when the lambda becomes capture ready.
7049 QualType CaptureType, DeclRefType;
7050 SourceLocation ExprLoc = VarExpr->getExprLoc();
7051 if (S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
7052 /*EllipsisLoc*/ SourceLocation(),
7053 /*BuildAndDiagnose*/false, CaptureType,
7054 DeclRefType, nullptr)) {
7055 // We will never be able to capture this variable, and we need
7056 // to be able to in any and all instantiations, so diagnose it.
7057 S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
7058 /*EllipsisLoc*/ SourceLocation(),
7059 /*BuildAndDiagnose*/true, CaptureType,
7060 DeclRefType, nullptr);
7065 // Check if 'this' needs to be captured.
7066 if (CurrentLSI->hasPotentialThisCapture()) {
7067 // If we have a capture-capable lambda for 'this', go ahead and capture
7068 // 'this' in that lambda (and all its enclosing lambdas).
7069 if (const Optional<unsigned> Index =
7070 getStackIndexOfNearestEnclosingCaptureCapableLambda(
7071 FunctionScopesArrayRef, /*0 is 'this'*/ nullptr, S)) {
7072 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
7073 S.CheckCXXThisCapture(CurrentLSI->PotentialThisCaptureLocation,
7074 /*Explicit*/ false, /*BuildAndDiagnose*/ true,
7075 &FunctionScopeIndexOfCapturableLambda);
7079 // Reset all the potential captures at the end of each full-expression.
7080 CurrentLSI->clearPotentialCaptures();
7083 static ExprResult attemptRecovery(Sema &SemaRef,
7084 const TypoCorrectionConsumer &Consumer,
7085 const TypoCorrection &TC) {
7086 LookupResult R(SemaRef, Consumer.getLookupResult().getLookupNameInfo(),
7087 Consumer.getLookupResult().getLookupKind());
7088 const CXXScopeSpec *SS = Consumer.getSS();
7091 // Use an approprate CXXScopeSpec for building the expr.
7092 if (auto *NNS = TC.getCorrectionSpecifier())
7093 NewSS.MakeTrivial(SemaRef.Context, NNS, TC.getCorrectionRange());
7094 else if (SS && !TC.WillReplaceSpecifier())
7097 if (auto *ND = TC.getFoundDecl()) {
7098 R.setLookupName(ND->getDeclName());
7100 if (ND->isCXXClassMember()) {
7101 // Figure out the correct naming class to add to the LookupResult.
7102 CXXRecordDecl *Record = nullptr;
7103 if (auto *NNS = TC.getCorrectionSpecifier())
7104 Record = NNS->getAsType()->getAsCXXRecordDecl();
7107 dyn_cast<CXXRecordDecl>(ND->getDeclContext()->getRedeclContext());
7109 R.setNamingClass(Record);
7111 // Detect and handle the case where the decl might be an implicit
7113 bool MightBeImplicitMember;
7114 if (!Consumer.isAddressOfOperand())
7115 MightBeImplicitMember = true;
7116 else if (!NewSS.isEmpty())
7117 MightBeImplicitMember = false;
7118 else if (R.isOverloadedResult())
7119 MightBeImplicitMember = false;
7120 else if (R.isUnresolvableResult())
7121 MightBeImplicitMember = true;
7123 MightBeImplicitMember = isa<FieldDecl>(ND) ||
7124 isa<IndirectFieldDecl>(ND) ||
7125 isa<MSPropertyDecl>(ND);
7127 if (MightBeImplicitMember)
7128 return SemaRef.BuildPossibleImplicitMemberExpr(
7129 NewSS, /*TemplateKWLoc*/ SourceLocation(), R,
7130 /*TemplateArgs*/ nullptr, /*S*/ nullptr);
7131 } else if (auto *Ivar = dyn_cast<ObjCIvarDecl>(ND)) {
7132 return SemaRef.LookupInObjCMethod(R, Consumer.getScope(),
7133 Ivar->getIdentifier());
7137 return SemaRef.BuildDeclarationNameExpr(NewSS, R, /*NeedsADL*/ false,
7138 /*AcceptInvalidDecl*/ true);
7142 class FindTypoExprs : public RecursiveASTVisitor<FindTypoExprs> {
7143 llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs;
7146 explicit FindTypoExprs(llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs)
7147 : TypoExprs(TypoExprs) {}
7148 bool VisitTypoExpr(TypoExpr *TE) {
7149 TypoExprs.insert(TE);
7154 class TransformTypos : public TreeTransform<TransformTypos> {
7155 typedef TreeTransform<TransformTypos> BaseTransform;
7157 VarDecl *InitDecl; // A decl to avoid as a correction because it is in the
7158 // process of being initialized.
7159 llvm::function_ref<ExprResult(Expr *)> ExprFilter;
7160 llvm::SmallSetVector<TypoExpr *, 2> TypoExprs, AmbiguousTypoExprs;
7161 llvm::SmallDenseMap<TypoExpr *, ExprResult, 2> TransformCache;
7162 llvm::SmallDenseMap<OverloadExpr *, Expr *, 4> OverloadResolution;
7164 /// \brief Emit diagnostics for all of the TypoExprs encountered.
7165 /// If the TypoExprs were successfully corrected, then the diagnostics should
7166 /// suggest the corrections. Otherwise the diagnostics will not suggest
7167 /// anything (having been passed an empty TypoCorrection).
7168 void EmitAllDiagnostics() {
7169 for (auto E : TypoExprs) {
7170 TypoExpr *TE = cast<TypoExpr>(E);
7171 auto &State = SemaRef.getTypoExprState(TE);
7172 if (State.DiagHandler) {
7173 TypoCorrection TC = State.Consumer->getCurrentCorrection();
7174 ExprResult Replacement = TransformCache[TE];
7176 // Extract the NamedDecl from the transformed TypoExpr and add it to the
7177 // TypoCorrection, replacing the existing decls. This ensures the right
7178 // NamedDecl is used in diagnostics e.g. in the case where overload
7179 // resolution was used to select one from several possible decls that
7180 // had been stored in the TypoCorrection.
7181 if (auto *ND = getDeclFromExpr(
7182 Replacement.isInvalid() ? nullptr : Replacement.get()))
7183 TC.setCorrectionDecl(ND);
7185 State.DiagHandler(TC);
7187 SemaRef.clearDelayedTypo(TE);
7191 /// \brief If corrections for the first TypoExpr have been exhausted for a
7192 /// given combination of the other TypoExprs, retry those corrections against
7193 /// the next combination of substitutions for the other TypoExprs by advancing
7194 /// to the next potential correction of the second TypoExpr. For the second
7195 /// and subsequent TypoExprs, if its stream of corrections has been exhausted,
7196 /// the stream is reset and the next TypoExpr's stream is advanced by one (a
7197 /// TypoExpr's correction stream is advanced by removing the TypoExpr from the
7198 /// TransformCache). Returns true if there is still any untried combinations
7200 bool CheckAndAdvanceTypoExprCorrectionStreams() {
7201 for (auto TE : TypoExprs) {
7202 auto &State = SemaRef.getTypoExprState(TE);
7203 TransformCache.erase(TE);
7204 if (!State.Consumer->finished())
7206 State.Consumer->resetCorrectionStream();
7211 NamedDecl *getDeclFromExpr(Expr *E) {
7212 if (auto *OE = dyn_cast_or_null<OverloadExpr>(E))
7213 E = OverloadResolution[OE];
7217 if (auto *DRE = dyn_cast<DeclRefExpr>(E))
7218 return DRE->getFoundDecl();
7219 if (auto *ME = dyn_cast<MemberExpr>(E))
7220 return ME->getFoundDecl();
7221 // FIXME: Add any other expr types that could be be seen by the delayed typo
7222 // correction TreeTransform for which the corresponding TypoCorrection could
7223 // contain multiple decls.
7227 ExprResult TryTransform(Expr *E) {
7228 Sema::SFINAETrap Trap(SemaRef);
7229 ExprResult Res = TransformExpr(E);
7230 if (Trap.hasErrorOccurred() || Res.isInvalid())
7233 return ExprFilter(Res.get());
7237 TransformTypos(Sema &SemaRef, VarDecl *InitDecl, llvm::function_ref<ExprResult(Expr *)> Filter)
7238 : BaseTransform(SemaRef), InitDecl(InitDecl), ExprFilter(Filter) {}
7240 ExprResult RebuildCallExpr(Expr *Callee, SourceLocation LParenLoc,
7242 SourceLocation RParenLoc,
7243 Expr *ExecConfig = nullptr) {
7244 auto Result = BaseTransform::RebuildCallExpr(Callee, LParenLoc, Args,
7245 RParenLoc, ExecConfig);
7246 if (auto *OE = dyn_cast<OverloadExpr>(Callee)) {
7247 if (Result.isUsable()) {
7248 Expr *ResultCall = Result.get();
7249 if (auto *BE = dyn_cast<CXXBindTemporaryExpr>(ResultCall))
7250 ResultCall = BE->getSubExpr();
7251 if (auto *CE = dyn_cast<CallExpr>(ResultCall))
7252 OverloadResolution[OE] = CE->getCallee();
7258 ExprResult TransformLambdaExpr(LambdaExpr *E) { return Owned(E); }
7260 ExprResult TransformBlockExpr(BlockExpr *E) { return Owned(E); }
7262 ExprResult Transform(Expr *E) {
7265 Res = TryTransform(E);
7267 // Exit if either the transform was valid or if there were no TypoExprs
7268 // to transform that still have any untried correction candidates..
7269 if (!Res.isInvalid() ||
7270 !CheckAndAdvanceTypoExprCorrectionStreams())
7274 // Ensure none of the TypoExprs have multiple typo correction candidates
7275 // with the same edit length that pass all the checks and filters.
7276 // TODO: Properly handle various permutations of possible corrections when
7277 // there is more than one potentially ambiguous typo correction.
7278 // Also, disable typo correction while attempting the transform when
7279 // handling potentially ambiguous typo corrections as any new TypoExprs will
7280 // have been introduced by the application of one of the correction
7281 // candidates and add little to no value if corrected.
7282 SemaRef.DisableTypoCorrection = true;
7283 while (!AmbiguousTypoExprs.empty()) {
7284 auto TE = AmbiguousTypoExprs.back();
7285 auto Cached = TransformCache[TE];
7286 auto &State = SemaRef.getTypoExprState(TE);
7287 State.Consumer->saveCurrentPosition();
7288 TransformCache.erase(TE);
7289 if (!TryTransform(E).isInvalid()) {
7290 State.Consumer->resetCorrectionStream();
7291 TransformCache.erase(TE);
7295 AmbiguousTypoExprs.remove(TE);
7296 State.Consumer->restoreSavedPosition();
7297 TransformCache[TE] = Cached;
7299 SemaRef.DisableTypoCorrection = false;
7301 // Ensure that all of the TypoExprs within the current Expr have been found.
7302 if (!Res.isUsable())
7303 FindTypoExprs(TypoExprs).TraverseStmt(E);
7305 EmitAllDiagnostics();
7310 ExprResult TransformTypoExpr(TypoExpr *E) {
7311 // If the TypoExpr hasn't been seen before, record it. Otherwise, return the
7312 // cached transformation result if there is one and the TypoExpr isn't the
7313 // first one that was encountered.
7314 auto &CacheEntry = TransformCache[E];
7315 if (!TypoExprs.insert(E) && !CacheEntry.isUnset()) {
7319 auto &State = SemaRef.getTypoExprState(E);
7320 assert(State.Consumer && "Cannot transform a cleared TypoExpr");
7322 // For the first TypoExpr and an uncached TypoExpr, find the next likely
7323 // typo correction and return it.
7324 while (TypoCorrection TC = State.Consumer->getNextCorrection()) {
7325 if (InitDecl && TC.getFoundDecl() == InitDecl)
7327 // FIXME: If we would typo-correct to an invalid declaration, it's
7328 // probably best to just suppress all errors from this typo correction.
7329 ExprResult NE = State.RecoveryHandler ?
7330 State.RecoveryHandler(SemaRef, E, TC) :
7331 attemptRecovery(SemaRef, *State.Consumer, TC);
7332 if (!NE.isInvalid()) {
7333 // Check whether there may be a second viable correction with the same
7334 // edit distance; if so, remember this TypoExpr may have an ambiguous
7335 // correction so it can be more thoroughly vetted later.
7336 TypoCorrection Next;
7337 if ((Next = State.Consumer->peekNextCorrection()) &&
7338 Next.getEditDistance(false) == TC.getEditDistance(false)) {
7339 AmbiguousTypoExprs.insert(E);
7341 AmbiguousTypoExprs.remove(E);
7343 assert(!NE.isUnset() &&
7344 "Typo was transformed into a valid-but-null ExprResult");
7345 return CacheEntry = NE;
7348 return CacheEntry = ExprError();
7354 Sema::CorrectDelayedTyposInExpr(Expr *E, VarDecl *InitDecl,
7355 llvm::function_ref<ExprResult(Expr *)> Filter) {
7356 // If the current evaluation context indicates there are uncorrected typos
7357 // and the current expression isn't guaranteed to not have typos, try to
7358 // resolve any TypoExpr nodes that might be in the expression.
7359 if (E && !ExprEvalContexts.empty() && ExprEvalContexts.back().NumTypos &&
7360 (E->isTypeDependent() || E->isValueDependent() ||
7361 E->isInstantiationDependent())) {
7362 auto TyposInContext = ExprEvalContexts.back().NumTypos;
7363 assert(TyposInContext < ~0U && "Recursive call of CorrectDelayedTyposInExpr");
7364 ExprEvalContexts.back().NumTypos = ~0U;
7365 auto TyposResolved = DelayedTypos.size();
7366 auto Result = TransformTypos(*this, InitDecl, Filter).Transform(E);
7367 ExprEvalContexts.back().NumTypos = TyposInContext;
7368 TyposResolved -= DelayedTypos.size();
7369 if (Result.isInvalid() || Result.get() != E) {
7370 ExprEvalContexts.back().NumTypos -= TyposResolved;
7373 assert(TyposResolved == 0 && "Corrected typo but got same Expr back?");
7378 ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC,
7379 bool DiscardedValue,
7381 bool IsLambdaInitCaptureInitializer) {
7382 ExprResult FullExpr = FE;
7384 if (!FullExpr.get())
7387 // If we are an init-expression in a lambdas init-capture, we should not
7388 // diagnose an unexpanded pack now (will be diagnosed once lambda-expr
7389 // containing full-expression is done).
7390 // template<class ... Ts> void test(Ts ... t) {
7391 // test([&a(t)]() { <-- (t) is an init-expr that shouldn't be diagnosed now.
7395 // FIXME: This is a hack. It would be better if we pushed the lambda scope
7396 // when we parse the lambda introducer, and teach capturing (but not
7397 // unexpanded pack detection) to walk over LambdaScopeInfos which don't have a
7398 // corresponding class yet (that is, have LambdaScopeInfo either represent a
7399 // lambda where we've entered the introducer but not the body, or represent a
7400 // lambda where we've entered the body, depending on where the
7401 // parser/instantiation has got to).
7402 if (!IsLambdaInitCaptureInitializer &&
7403 DiagnoseUnexpandedParameterPack(FullExpr.get()))
7406 // Top-level expressions default to 'id' when we're in a debugger.
7407 if (DiscardedValue && getLangOpts().DebuggerCastResultToId &&
7408 FullExpr.get()->getType() == Context.UnknownAnyTy) {
7409 FullExpr = forceUnknownAnyToType(FullExpr.get(), Context.getObjCIdType());
7410 if (FullExpr.isInvalid())
7414 if (DiscardedValue) {
7415 FullExpr = CheckPlaceholderExpr(FullExpr.get());
7416 if (FullExpr.isInvalid())
7419 FullExpr = IgnoredValueConversions(FullExpr.get());
7420 if (FullExpr.isInvalid())
7424 FullExpr = CorrectDelayedTyposInExpr(FullExpr.get());
7425 if (FullExpr.isInvalid())
7428 CheckCompletedExpr(FullExpr.get(), CC, IsConstexpr);
7430 // At the end of this full expression (which could be a deeply nested
7431 // lambda), if there is a potential capture within the nested lambda,
7432 // have the outer capture-able lambda try and capture it.
7433 // Consider the following code:
7434 // void f(int, int);
7435 // void f(const int&, double);
7437 // const int x = 10, y = 20;
7438 // auto L = [=](auto a) {
7439 // auto M = [=](auto b) {
7440 // f(x, b); <-- requires x to be captured by L and M
7441 // f(y, a); <-- requires y to be captured by L, but not all Ms
7446 // FIXME: Also consider what happens for something like this that involves
7447 // the gnu-extension statement-expressions or even lambda-init-captures:
7450 // auto L = [&](auto a) {
7451 // +n + ({ 0; a; });
7455 // Here, we see +n, and then the full-expression 0; ends, so we don't
7456 // capture n (and instead remove it from our list of potential captures),
7457 // and then the full-expression +n + ({ 0; }); ends, but it's too late
7458 // for us to see that we need to capture n after all.
7460 LambdaScopeInfo *const CurrentLSI =
7461 getCurLambda(/*IgnoreCapturedRegions=*/true);
7462 // FIXME: PR 17877 showed that getCurLambda() can return a valid pointer
7463 // even if CurContext is not a lambda call operator. Refer to that Bug Report
7464 // for an example of the code that might cause this asynchrony.
7465 // By ensuring we are in the context of a lambda's call operator
7466 // we can fix the bug (we only need to check whether we need to capture
7467 // if we are within a lambda's body); but per the comments in that
7468 // PR, a proper fix would entail :
7469 // "Alternative suggestion:
7470 // - Add to Sema an integer holding the smallest (outermost) scope
7471 // index that we are *lexically* within, and save/restore/set to
7472 // FunctionScopes.size() in InstantiatingTemplate's
7473 // constructor/destructor.
7474 // - Teach the handful of places that iterate over FunctionScopes to
7475 // stop at the outermost enclosing lexical scope."
7476 DeclContext *DC = CurContext;
7477 while (DC && isa<CapturedDecl>(DC))
7478 DC = DC->getParent();
7479 const bool IsInLambdaDeclContext = isLambdaCallOperator(DC);
7480 if (IsInLambdaDeclContext && CurrentLSI &&
7481 CurrentLSI->hasPotentialCaptures() && !FullExpr.isInvalid())
7482 CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(FE, CurrentLSI,
7484 return MaybeCreateExprWithCleanups(FullExpr);
7487 StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) {
7488 if (!FullStmt) return StmtError();
7490 return MaybeCreateStmtWithCleanups(FullStmt);
7493 Sema::IfExistsResult
7494 Sema::CheckMicrosoftIfExistsSymbol(Scope *S,
7496 const DeclarationNameInfo &TargetNameInfo) {
7497 DeclarationName TargetName = TargetNameInfo.getName();
7499 return IER_DoesNotExist;
7501 // If the name itself is dependent, then the result is dependent.
7502 if (TargetName.isDependentName())
7503 return IER_Dependent;
7505 // Do the redeclaration lookup in the current scope.
7506 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName,
7507 Sema::NotForRedeclaration);
7508 LookupParsedName(R, S, &SS);
7509 R.suppressDiagnostics();
7511 switch (R.getResultKind()) {
7512 case LookupResult::Found:
7513 case LookupResult::FoundOverloaded:
7514 case LookupResult::FoundUnresolvedValue:
7515 case LookupResult::Ambiguous:
7518 case LookupResult::NotFound:
7519 return IER_DoesNotExist;
7521 case LookupResult::NotFoundInCurrentInstantiation:
7522 return IER_Dependent;
7525 llvm_unreachable("Invalid LookupResult Kind!");
7528 Sema::IfExistsResult
7529 Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc,
7530 bool IsIfExists, CXXScopeSpec &SS,
7531 UnqualifiedId &Name) {
7532 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
7534 // Check for an unexpanded parameter pack.
7535 auto UPPC = IsIfExists ? UPPC_IfExists : UPPC_IfNotExists;
7536 if (DiagnoseUnexpandedParameterPack(SS, UPPC) ||
7537 DiagnoseUnexpandedParameterPack(TargetNameInfo, UPPC))
7540 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo);