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::getDestructorType(const DeclSpec& DS, ParsedType ObjectType) {
327 if (DS.getTypeSpecType() == DeclSpec::TST_error || !ObjectType)
329 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype
330 && "only get destructor types from declspecs");
331 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
332 QualType SearchType = GetTypeFromParser(ObjectType);
333 if (SearchType->isDependentType() || Context.hasSameUnqualifiedType(SearchType, T)) {
334 return ParsedType::make(T);
337 Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch)
342 bool Sema::checkLiteralOperatorId(const CXXScopeSpec &SS,
343 const UnqualifiedId &Name) {
344 assert(Name.getKind() == UnqualifiedId::IK_LiteralOperatorId);
349 switch (SS.getScopeRep()->getKind()) {
350 case NestedNameSpecifier::Identifier:
351 case NestedNameSpecifier::TypeSpec:
352 case NestedNameSpecifier::TypeSpecWithTemplate:
353 // Per C++11 [over.literal]p2, literal operators can only be declared at
354 // namespace scope. Therefore, this unqualified-id cannot name anything.
355 // Reject it early, because we have no AST representation for this in the
356 // case where the scope is dependent.
357 Diag(Name.getLocStart(), diag::err_literal_operator_id_outside_namespace)
361 case NestedNameSpecifier::Global:
362 case NestedNameSpecifier::Super:
363 case NestedNameSpecifier::Namespace:
364 case NestedNameSpecifier::NamespaceAlias:
368 llvm_unreachable("unknown nested name specifier kind");
371 /// \brief Build a C++ typeid expression with a type operand.
372 ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
373 SourceLocation TypeidLoc,
374 TypeSourceInfo *Operand,
375 SourceLocation RParenLoc) {
376 // C++ [expr.typeid]p4:
377 // The top-level cv-qualifiers of the lvalue expression or the type-id
378 // that is the operand of typeid are always ignored.
379 // If the type of the type-id is a class type or a reference to a class
380 // type, the class shall be completely-defined.
383 = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(),
385 if (T->getAs<RecordType>() &&
386 RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
389 if (T->isVariablyModifiedType())
390 return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid) << T);
392 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), Operand,
393 SourceRange(TypeidLoc, RParenLoc));
396 /// \brief Build a C++ typeid expression with an expression operand.
397 ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
398 SourceLocation TypeidLoc,
400 SourceLocation RParenLoc) {
401 bool WasEvaluated = false;
402 if (E && !E->isTypeDependent()) {
403 if (E->getType()->isPlaceholderType()) {
404 ExprResult result = CheckPlaceholderExpr(E);
405 if (result.isInvalid()) return ExprError();
409 QualType T = E->getType();
410 if (const RecordType *RecordT = T->getAs<RecordType>()) {
411 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl());
412 // C++ [expr.typeid]p3:
413 // [...] If the type of the expression is a class type, the class
414 // shall be completely-defined.
415 if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
418 // C++ [expr.typeid]p3:
419 // When typeid is applied to an expression other than an glvalue of a
420 // polymorphic class type [...] [the] expression is an unevaluated
422 if (RecordD->isPolymorphic() && E->isGLValue()) {
423 // The subexpression is potentially evaluated; switch the context
424 // and recheck the subexpression.
425 ExprResult Result = TransformToPotentiallyEvaluated(E);
426 if (Result.isInvalid()) return ExprError();
429 // We require a vtable to query the type at run time.
430 MarkVTableUsed(TypeidLoc, RecordD);
435 // C++ [expr.typeid]p4:
436 // [...] If the type of the type-id is a reference to a possibly
437 // cv-qualified type, the result of the typeid expression refers to a
438 // std::type_info object representing the cv-unqualified referenced
441 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals);
442 if (!Context.hasSameType(T, UnqualT)) {
444 E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).get();
448 if (E->getType()->isVariablyModifiedType())
449 return ExprError(Diag(TypeidLoc, diag::err_variably_modified_typeid)
451 else if (ActiveTemplateInstantiations.empty() &&
452 E->HasSideEffects(Context, WasEvaluated)) {
453 // The expression operand for typeid is in an unevaluated expression
454 // context, so side effects could result in unintended consequences.
455 Diag(E->getExprLoc(), WasEvaluated
456 ? diag::warn_side_effects_typeid
457 : diag::warn_side_effects_unevaluated_context);
460 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), E,
461 SourceRange(TypeidLoc, RParenLoc));
464 /// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression);
466 Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc,
467 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
468 // Find the std::type_info type.
469 if (!getStdNamespace())
470 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
472 if (!CXXTypeInfoDecl) {
473 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info");
474 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName);
475 LookupQualifiedName(R, getStdNamespace());
476 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
477 // Microsoft's typeinfo doesn't have type_info in std but in the global
478 // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153.
479 if (!CXXTypeInfoDecl && LangOpts.MSVCCompat) {
480 LookupQualifiedName(R, Context.getTranslationUnitDecl());
481 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
483 if (!CXXTypeInfoDecl)
484 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
487 if (!getLangOpts().RTTI) {
488 return ExprError(Diag(OpLoc, diag::err_no_typeid_with_fno_rtti));
491 QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl);
494 // The operand is a type; handle it as such.
495 TypeSourceInfo *TInfo = nullptr;
496 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
502 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
504 return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc);
507 // The operand is an expression.
508 return BuildCXXTypeId(TypeInfoType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
511 /// Grabs __declspec(uuid()) off a type, or returns 0 if we cannot resolve to
514 getUuidAttrOfType(Sema &SemaRef, QualType QT,
515 llvm::SmallSetVector<const UuidAttr *, 1> &UuidAttrs) {
516 // Optionally remove one level of pointer, reference or array indirection.
517 const Type *Ty = QT.getTypePtr();
518 if (QT->isPointerType() || QT->isReferenceType())
519 Ty = QT->getPointeeType().getTypePtr();
520 else if (QT->isArrayType())
521 Ty = Ty->getBaseElementTypeUnsafe();
523 const auto *TD = Ty->getAsTagDecl();
527 if (const auto *Uuid = TD->getMostRecentDecl()->getAttr<UuidAttr>()) {
528 UuidAttrs.insert(Uuid);
532 // __uuidof can grab UUIDs from template arguments.
533 if (const auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(TD)) {
534 const TemplateArgumentList &TAL = CTSD->getTemplateArgs();
535 for (const TemplateArgument &TA : TAL.asArray()) {
536 const UuidAttr *UuidForTA = nullptr;
537 if (TA.getKind() == TemplateArgument::Type)
538 getUuidAttrOfType(SemaRef, TA.getAsType(), UuidAttrs);
539 else if (TA.getKind() == TemplateArgument::Declaration)
540 getUuidAttrOfType(SemaRef, TA.getAsDecl()->getType(), UuidAttrs);
543 UuidAttrs.insert(UuidForTA);
548 /// \brief Build a Microsoft __uuidof expression with a type operand.
549 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType,
550 SourceLocation TypeidLoc,
551 TypeSourceInfo *Operand,
552 SourceLocation RParenLoc) {
554 if (!Operand->getType()->isDependentType()) {
555 llvm::SmallSetVector<const UuidAttr *, 1> UuidAttrs;
556 getUuidAttrOfType(*this, Operand->getType(), UuidAttrs);
557 if (UuidAttrs.empty())
558 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
559 if (UuidAttrs.size() > 1)
560 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
561 UuidStr = UuidAttrs.back()->getGuid();
564 return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), Operand, UuidStr,
565 SourceRange(TypeidLoc, RParenLoc));
568 /// \brief Build a Microsoft __uuidof expression with an expression operand.
569 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType,
570 SourceLocation TypeidLoc,
572 SourceLocation RParenLoc) {
574 if (!E->getType()->isDependentType()) {
575 if (E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
576 UuidStr = "00000000-0000-0000-0000-000000000000";
578 llvm::SmallSetVector<const UuidAttr *, 1> UuidAttrs;
579 getUuidAttrOfType(*this, E->getType(), UuidAttrs);
580 if (UuidAttrs.empty())
581 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
582 if (UuidAttrs.size() > 1)
583 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
584 UuidStr = UuidAttrs.back()->getGuid();
588 return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), E, UuidStr,
589 SourceRange(TypeidLoc, RParenLoc));
592 /// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression);
594 Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc,
595 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
596 // If MSVCGuidDecl has not been cached, do the lookup.
598 IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID");
599 LookupResult R(*this, GuidII, SourceLocation(), LookupTagName);
600 LookupQualifiedName(R, Context.getTranslationUnitDecl());
601 MSVCGuidDecl = R.getAsSingle<RecordDecl>();
603 return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof));
606 QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl);
609 // The operand is a type; handle it as such.
610 TypeSourceInfo *TInfo = nullptr;
611 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
617 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
619 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc);
622 // The operand is an expression.
623 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
626 /// ActOnCXXBoolLiteral - Parse {true,false} literals.
628 Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
629 assert((Kind == tok::kw_true || Kind == tok::kw_false) &&
630 "Unknown C++ Boolean value!");
632 CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc);
635 /// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
637 Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) {
638 return new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
641 /// ActOnCXXThrow - Parse throw expressions.
643 Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) {
644 bool IsThrownVarInScope = false;
646 // C++0x [class.copymove]p31:
647 // When certain criteria are met, an implementation is allowed to omit the
648 // copy/move construction of a class object [...]
650 // - in a throw-expression, when the operand is the name of a
651 // non-volatile automatic object (other than a function or catch-
652 // clause parameter) whose scope does not extend beyond the end of the
653 // innermost enclosing try-block (if there is one), the copy/move
654 // operation from the operand to the exception object (15.1) can be
655 // omitted by constructing the automatic object directly into the
657 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens()))
658 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
659 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) {
660 for( ; S; S = S->getParent()) {
661 if (S->isDeclScope(Var)) {
662 IsThrownVarInScope = true;
667 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope |
668 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope |
676 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope);
679 ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex,
680 bool IsThrownVarInScope) {
681 // Don't report an error if 'throw' is used in system headers.
682 if (!getLangOpts().CXXExceptions &&
683 !getSourceManager().isInSystemHeader(OpLoc))
684 Diag(OpLoc, diag::err_exceptions_disabled) << "throw";
686 // Exceptions aren't allowed in CUDA device code.
687 if (getLangOpts().CUDA)
688 CUDADiagIfDeviceCode(OpLoc, diag::err_cuda_device_exceptions)
689 << "throw" << CurrentCUDATarget();
691 if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
692 Diag(OpLoc, diag::err_omp_simd_region_cannot_use_stmt) << "throw";
694 if (Ex && !Ex->isTypeDependent()) {
695 QualType ExceptionObjectTy = Context.getExceptionObjectType(Ex->getType());
696 if (CheckCXXThrowOperand(OpLoc, ExceptionObjectTy, Ex))
699 // Initialize the exception result. This implicitly weeds out
700 // abstract types or types with inaccessible copy constructors.
702 // C++0x [class.copymove]p31:
703 // When certain criteria are met, an implementation is allowed to omit the
704 // copy/move construction of a class object [...]
706 // - in a throw-expression, when the operand is the name of a
707 // non-volatile automatic object (other than a function or
709 // parameter) whose scope does not extend beyond the end of the
710 // innermost enclosing try-block (if there is one), the copy/move
711 // operation from the operand to the exception object (15.1) can be
712 // omitted by constructing the automatic object directly into the
714 const VarDecl *NRVOVariable = nullptr;
715 if (IsThrownVarInScope)
716 NRVOVariable = getCopyElisionCandidate(QualType(), Ex, false);
718 InitializedEntity Entity = InitializedEntity::InitializeException(
719 OpLoc, ExceptionObjectTy,
720 /*NRVO=*/NRVOVariable != nullptr);
721 ExprResult Res = PerformMoveOrCopyInitialization(
722 Entity, NRVOVariable, QualType(), Ex, IsThrownVarInScope);
729 CXXThrowExpr(Ex, Context.VoidTy, OpLoc, IsThrownVarInScope);
733 collectPublicBases(CXXRecordDecl *RD,
734 llvm::DenseMap<CXXRecordDecl *, unsigned> &SubobjectsSeen,
735 llvm::SmallPtrSetImpl<CXXRecordDecl *> &VBases,
736 llvm::SetVector<CXXRecordDecl *> &PublicSubobjectsSeen,
737 bool ParentIsPublic) {
738 for (const CXXBaseSpecifier &BS : RD->bases()) {
739 CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
741 // Virtual bases constitute the same subobject. Non-virtual bases are
742 // always distinct subobjects.
744 NewSubobject = VBases.insert(BaseDecl).second;
749 ++SubobjectsSeen[BaseDecl];
751 // Only add subobjects which have public access throughout the entire chain.
752 bool PublicPath = ParentIsPublic && BS.getAccessSpecifier() == AS_public;
754 PublicSubobjectsSeen.insert(BaseDecl);
756 // Recurse on to each base subobject.
757 collectPublicBases(BaseDecl, SubobjectsSeen, VBases, PublicSubobjectsSeen,
762 static void getUnambiguousPublicSubobjects(
763 CXXRecordDecl *RD, llvm::SmallVectorImpl<CXXRecordDecl *> &Objects) {
764 llvm::DenseMap<CXXRecordDecl *, unsigned> SubobjectsSeen;
765 llvm::SmallSet<CXXRecordDecl *, 2> VBases;
766 llvm::SetVector<CXXRecordDecl *> PublicSubobjectsSeen;
767 SubobjectsSeen[RD] = 1;
768 PublicSubobjectsSeen.insert(RD);
769 collectPublicBases(RD, SubobjectsSeen, VBases, PublicSubobjectsSeen,
770 /*ParentIsPublic=*/true);
772 for (CXXRecordDecl *PublicSubobject : PublicSubobjectsSeen) {
773 // Skip ambiguous objects.
774 if (SubobjectsSeen[PublicSubobject] > 1)
777 Objects.push_back(PublicSubobject);
781 /// CheckCXXThrowOperand - Validate the operand of a throw.
782 bool Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc,
783 QualType ExceptionObjectTy, Expr *E) {
784 // If the type of the exception would be an incomplete type or a pointer
785 // to an incomplete type other than (cv) void the program is ill-formed.
786 QualType Ty = ExceptionObjectTy;
787 bool isPointer = false;
788 if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
789 Ty = Ptr->getPointeeType();
792 if (!isPointer || !Ty->isVoidType()) {
793 if (RequireCompleteType(ThrowLoc, Ty,
794 isPointer ? diag::err_throw_incomplete_ptr
795 : diag::err_throw_incomplete,
796 E->getSourceRange()))
799 if (RequireNonAbstractType(ThrowLoc, ExceptionObjectTy,
800 diag::err_throw_abstract_type, E))
804 // If the exception has class type, we need additional handling.
805 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
809 // If we are throwing a polymorphic class type or pointer thereof,
810 // exception handling will make use of the vtable.
811 MarkVTableUsed(ThrowLoc, RD);
813 // If a pointer is thrown, the referenced object will not be destroyed.
817 // If the class has a destructor, we must be able to call it.
818 if (!RD->hasIrrelevantDestructor()) {
819 if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
820 MarkFunctionReferenced(E->getExprLoc(), Destructor);
821 CheckDestructorAccess(E->getExprLoc(), Destructor,
822 PDiag(diag::err_access_dtor_exception) << Ty);
823 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
828 // The MSVC ABI creates a list of all types which can catch the exception
829 // object. This list also references the appropriate copy constructor to call
830 // if the object is caught by value and has a non-trivial copy constructor.
831 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
832 // We are only interested in the public, unambiguous bases contained within
833 // the exception object. Bases which are ambiguous or otherwise
834 // inaccessible are not catchable types.
835 llvm::SmallVector<CXXRecordDecl *, 2> UnambiguousPublicSubobjects;
836 getUnambiguousPublicSubobjects(RD, UnambiguousPublicSubobjects);
838 for (CXXRecordDecl *Subobject : UnambiguousPublicSubobjects) {
839 // Attempt to lookup the copy constructor. Various pieces of machinery
840 // will spring into action, like template instantiation, which means this
841 // cannot be a simple walk of the class's decls. Instead, we must perform
842 // lookup and overload resolution.
843 CXXConstructorDecl *CD = LookupCopyingConstructor(Subobject, 0);
847 // Mark the constructor referenced as it is used by this throw expression.
848 MarkFunctionReferenced(E->getExprLoc(), CD);
850 // Skip this copy constructor if it is trivial, we don't need to record it
851 // in the catchable type data.
855 // The copy constructor is non-trivial, create a mapping from this class
856 // type to this constructor.
857 // N.B. The selection of copy constructor is not sensitive to this
858 // particular throw-site. Lookup will be performed at the catch-site to
859 // ensure that the copy constructor is, in fact, accessible (via
860 // friendship or any other means).
861 Context.addCopyConstructorForExceptionObject(Subobject, CD);
863 // We don't keep the instantiated default argument expressions around so
864 // we must rebuild them here.
865 for (unsigned I = 1, E = CD->getNumParams(); I != E; ++I) {
866 if (CheckCXXDefaultArgExpr(ThrowLoc, CD, CD->getParamDecl(I)))
875 static QualType adjustCVQualifiersForCXXThisWithinLambda(
876 ArrayRef<FunctionScopeInfo *> FunctionScopes, QualType ThisTy,
877 DeclContext *CurSemaContext, ASTContext &ASTCtx) {
879 QualType ClassType = ThisTy->getPointeeType();
880 LambdaScopeInfo *CurLSI = nullptr;
881 DeclContext *CurDC = CurSemaContext;
883 // Iterate through the stack of lambdas starting from the innermost lambda to
884 // the outermost lambda, checking if '*this' is ever captured by copy - since
885 // that could change the cv-qualifiers of the '*this' object.
886 // The object referred to by '*this' starts out with the cv-qualifiers of its
887 // member function. We then start with the innermost lambda and iterate
888 // outward checking to see if any lambda performs a by-copy capture of '*this'
889 // - and if so, any nested lambda must respect the 'constness' of that
890 // capturing lamdbda's call operator.
893 // The issue is that we cannot rely entirely on the FunctionScopeInfo stack
894 // since ScopeInfos are pushed on during parsing and treetransforming. But
895 // since a generic lambda's call operator can be instantiated anywhere (even
896 // end of the TU) we need to be able to examine its enclosing lambdas and so
897 // we use the DeclContext to get a hold of the closure-class and query it for
898 // capture information. The reason we don't just resort to always using the
899 // DeclContext chain is that it is only mature for lambda expressions
900 // enclosing generic lambda's call operators that are being instantiated.
902 for (int I = FunctionScopes.size();
903 I-- && isa<LambdaScopeInfo>(FunctionScopes[I]);
904 CurDC = getLambdaAwareParentOfDeclContext(CurDC)) {
905 CurLSI = cast<LambdaScopeInfo>(FunctionScopes[I]);
907 if (!CurLSI->isCXXThisCaptured())
910 auto C = CurLSI->getCXXThisCapture();
912 if (C.isCopyCapture()) {
913 ClassType.removeLocalCVRQualifiers(Qualifiers::CVRMask);
914 if (CurLSI->CallOperator->isConst())
915 ClassType.addConst();
916 return ASTCtx.getPointerType(ClassType);
919 // We've run out of ScopeInfos but check if CurDC is a lambda (which can
920 // happen during instantiation of generic lambdas)
921 if (isLambdaCallOperator(CurDC)) {
923 assert(isGenericLambdaCallOperatorSpecialization(CurLSI->CallOperator));
924 assert(CurDC == getLambdaAwareParentOfDeclContext(CurLSI->CallOperator));
926 auto IsThisCaptured =
927 [](CXXRecordDecl *Closure, bool &IsByCopy, bool &IsConst) {
930 for (auto &&C : Closure->captures()) {
931 if (C.capturesThis()) {
932 if (C.getCaptureKind() == LCK_StarThis)
934 if (Closure->getLambdaCallOperator()->isConst())
942 bool IsByCopyCapture = false;
943 bool IsConstCapture = false;
944 CXXRecordDecl *Closure = cast<CXXRecordDecl>(CurDC->getParent());
946 IsThisCaptured(Closure, IsByCopyCapture, IsConstCapture)) {
947 if (IsByCopyCapture) {
948 ClassType.removeLocalCVRQualifiers(Qualifiers::CVRMask);
950 ClassType.addConst();
951 return ASTCtx.getPointerType(ClassType);
953 Closure = isLambdaCallOperator(Closure->getParent())
954 ? cast<CXXRecordDecl>(Closure->getParent()->getParent())
958 return ASTCtx.getPointerType(ClassType);
961 QualType Sema::getCurrentThisType() {
962 DeclContext *DC = getFunctionLevelDeclContext();
963 QualType ThisTy = CXXThisTypeOverride;
965 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) {
966 if (method && method->isInstance())
967 ThisTy = method->getThisType(Context);
970 if (ThisTy.isNull() && isLambdaCallOperator(CurContext) &&
971 !ActiveTemplateInstantiations.empty()) {
973 assert(isa<CXXRecordDecl>(DC) &&
974 "Trying to get 'this' type from static method?");
976 // This is a lambda call operator that is being instantiated as a default
977 // initializer. DC must point to the enclosing class type, so we can recover
978 // the 'this' type from it.
980 QualType ClassTy = Context.getTypeDeclType(cast<CXXRecordDecl>(DC));
981 // There are no cv-qualifiers for 'this' within default initializers,
982 // per [expr.prim.general]p4.
983 ThisTy = Context.getPointerType(ClassTy);
986 // If we are within a lambda's call operator, the cv-qualifiers of 'this'
987 // might need to be adjusted if the lambda or any of its enclosing lambda's
988 // captures '*this' by copy.
989 if (!ThisTy.isNull() && isLambdaCallOperator(CurContext))
990 return adjustCVQualifiersForCXXThisWithinLambda(FunctionScopes, ThisTy,
991 CurContext, Context);
995 Sema::CXXThisScopeRAII::CXXThisScopeRAII(Sema &S,
997 unsigned CXXThisTypeQuals,
999 : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false)
1001 if (!Enabled || !ContextDecl)
1004 CXXRecordDecl *Record = nullptr;
1005 if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl))
1006 Record = Template->getTemplatedDecl();
1008 Record = cast<CXXRecordDecl>(ContextDecl);
1010 // We care only for CVR qualifiers here, so cut everything else.
1011 CXXThisTypeQuals &= Qualifiers::FastMask;
1012 S.CXXThisTypeOverride
1013 = S.Context.getPointerType(
1014 S.Context.getRecordType(Record).withCVRQualifiers(CXXThisTypeQuals));
1016 this->Enabled = true;
1020 Sema::CXXThisScopeRAII::~CXXThisScopeRAII() {
1022 S.CXXThisTypeOverride = OldCXXThisTypeOverride;
1026 static Expr *captureThis(Sema &S, ASTContext &Context, RecordDecl *RD,
1027 QualType ThisTy, SourceLocation Loc,
1028 const bool ByCopy) {
1030 QualType AdjustedThisTy = ThisTy;
1031 // The type of the corresponding data member (not a 'this' pointer if 'by
1033 QualType CaptureThisFieldTy = ThisTy;
1035 // If we are capturing the object referred to by '*this' by copy, ignore any
1036 // cv qualifiers inherited from the type of the member function for the type
1037 // of the closure-type's corresponding data member and any use of 'this'.
1038 CaptureThisFieldTy = ThisTy->getPointeeType();
1039 CaptureThisFieldTy.removeLocalCVRQualifiers(Qualifiers::CVRMask);
1040 AdjustedThisTy = Context.getPointerType(CaptureThisFieldTy);
1043 FieldDecl *Field = FieldDecl::Create(
1044 Context, RD, Loc, Loc, nullptr, CaptureThisFieldTy,
1045 Context.getTrivialTypeSourceInfo(CaptureThisFieldTy, Loc), nullptr, false,
1048 Field->setImplicit(true);
1049 Field->setAccess(AS_private);
1052 new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit*/ true);
1054 Expr *StarThis = S.CreateBuiltinUnaryOp(Loc,
1057 InitializedEntity Entity = InitializedEntity::InitializeLambdaCapture(
1058 nullptr, CaptureThisFieldTy, Loc);
1059 InitializationKind InitKind = InitializationKind::CreateDirect(Loc, Loc, Loc);
1060 InitializationSequence Init(S, Entity, InitKind, StarThis);
1061 ExprResult ER = Init.Perform(S, Entity, InitKind, StarThis);
1062 if (ER.isInvalid()) return nullptr;
1068 bool Sema::CheckCXXThisCapture(SourceLocation Loc, const bool Explicit,
1069 bool BuildAndDiagnose, const unsigned *const FunctionScopeIndexToStopAt,
1070 const bool ByCopy) {
1071 // We don't need to capture this in an unevaluated context.
1072 if (isUnevaluatedContext() && !Explicit)
1075 assert((!ByCopy || Explicit) && "cannot implicitly capture *this by value");
1077 const unsigned MaxFunctionScopesIndex = FunctionScopeIndexToStopAt ?
1078 *FunctionScopeIndexToStopAt : FunctionScopes.size() - 1;
1080 // Check that we can capture the *enclosing object* (referred to by '*this')
1081 // by the capturing-entity/closure (lambda/block/etc) at
1082 // MaxFunctionScopesIndex-deep on the FunctionScopes stack.
1084 // Note: The *enclosing object* can only be captured by-value by a
1085 // closure that is a lambda, using the explicit notation:
1087 // Every other capture of the *enclosing object* results in its by-reference
1090 // For a closure 'L' (at MaxFunctionScopesIndex in the FunctionScopes
1091 // stack), we can capture the *enclosing object* only if:
1092 // - 'L' has an explicit byref or byval capture of the *enclosing object*
1093 // - or, 'L' has an implicit capture.
1095 // -- there is no enclosing closure
1096 // -- or, there is some enclosing closure 'E' that has already captured the
1097 // *enclosing object*, and every intervening closure (if any) between 'E'
1098 // and 'L' can implicitly capture the *enclosing object*.
1099 // -- or, every enclosing closure can implicitly capture the
1100 // *enclosing object*
1103 unsigned NumCapturingClosures = 0;
1104 for (unsigned idx = MaxFunctionScopesIndex; idx != 0; idx--) {
1105 if (CapturingScopeInfo *CSI =
1106 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) {
1107 if (CSI->CXXThisCaptureIndex != 0) {
1108 // 'this' is already being captured; there isn't anything more to do.
1111 LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI);
1112 if (LSI && isGenericLambdaCallOperatorSpecialization(LSI->CallOperator)) {
1113 // This context can't implicitly capture 'this'; fail out.
1114 if (BuildAndDiagnose)
1115 Diag(Loc, diag::err_this_capture)
1116 << (Explicit && idx == MaxFunctionScopesIndex);
1119 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref ||
1120 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval ||
1121 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block ||
1122 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_CapturedRegion ||
1123 (Explicit && idx == MaxFunctionScopesIndex)) {
1124 // Regarding (Explicit && idx == MaxFunctionScopesIndex): only the first
1125 // iteration through can be an explicit capture, all enclosing closures,
1126 // if any, must perform implicit captures.
1128 // This closure can capture 'this'; continue looking upwards.
1129 NumCapturingClosures++;
1132 // This context can't implicitly capture 'this'; fail out.
1133 if (BuildAndDiagnose)
1134 Diag(Loc, diag::err_this_capture)
1135 << (Explicit && idx == MaxFunctionScopesIndex);
1140 if (!BuildAndDiagnose) return false;
1142 // If we got here, then the closure at MaxFunctionScopesIndex on the
1143 // FunctionScopes stack, can capture the *enclosing object*, so capture it
1144 // (including implicit by-reference captures in any enclosing closures).
1146 // In the loop below, respect the ByCopy flag only for the closure requesting
1147 // the capture (i.e. first iteration through the loop below). Ignore it for
1148 // all enclosing closure's up to NumCapturingClosures (since they must be
1149 // implicitly capturing the *enclosing object* by reference (see loop
1152 dyn_cast<LambdaScopeInfo>(FunctionScopes[MaxFunctionScopesIndex])) &&
1153 "Only a lambda can capture the enclosing object (referred to by "
1155 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated
1157 QualType ThisTy = getCurrentThisType();
1158 for (unsigned idx = MaxFunctionScopesIndex; NumCapturingClosures;
1159 --idx, --NumCapturingClosures) {
1160 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]);
1161 Expr *ThisExpr = nullptr;
1163 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI)) {
1164 // For lambda expressions, build a field and an initializing expression,
1165 // and capture the *enclosing object* by copy only if this is the first
1167 ThisExpr = captureThis(*this, Context, LSI->Lambda, ThisTy, Loc,
1168 ByCopy && idx == MaxFunctionScopesIndex);
1170 } else if (CapturedRegionScopeInfo *RSI
1171 = dyn_cast<CapturedRegionScopeInfo>(FunctionScopes[idx]))
1173 captureThis(*this, Context, RSI->TheRecordDecl, ThisTy, Loc,
1176 bool isNested = NumCapturingClosures > 1;
1177 CSI->addThisCapture(isNested, Loc, ThisExpr, ByCopy);
1182 ExprResult Sema::ActOnCXXThis(SourceLocation Loc) {
1183 /// C++ 9.3.2: In the body of a non-static member function, the keyword this
1184 /// is a non-lvalue expression whose value is the address of the object for
1185 /// which the function is called.
1187 QualType ThisTy = getCurrentThisType();
1188 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use);
1190 CheckCXXThisCapture(Loc);
1191 return new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false);
1194 bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) {
1195 // If we're outside the body of a member function, then we'll have a specified
1197 if (CXXThisTypeOverride.isNull())
1200 // Determine whether we're looking into a class that's currently being
1202 CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl();
1203 return Class && Class->isBeingDefined();
1207 Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep,
1208 SourceLocation LParenLoc,
1210 SourceLocation RParenLoc) {
1214 TypeSourceInfo *TInfo;
1215 QualType Ty = GetTypeFromParser(TypeRep, &TInfo);
1217 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation());
1219 // Handle errors like: int({0})
1220 if (exprs.size() == 1 && !canInitializeWithParenthesizedList(Ty) &&
1221 LParenLoc.isValid() && RParenLoc.isValid())
1222 if (auto IList = dyn_cast<InitListExpr>(exprs[0])) {
1223 Diag(TInfo->getTypeLoc().getLocStart(), diag::err_list_init_in_parens)
1224 << Ty << IList->getSourceRange()
1225 << FixItHint::CreateRemoval(LParenLoc)
1226 << FixItHint::CreateRemoval(RParenLoc);
1227 LParenLoc = RParenLoc = SourceLocation();
1230 auto Result = BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc);
1231 // Avoid creating a non-type-dependent expression that contains typos.
1232 // Non-type-dependent expressions are liable to be discarded without
1233 // checking for embedded typos.
1234 if (!Result.isInvalid() && Result.get()->isInstantiationDependent() &&
1235 !Result.get()->isTypeDependent())
1236 Result = CorrectDelayedTyposInExpr(Result.get());
1240 /// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
1241 /// Can be interpreted either as function-style casting ("int(x)")
1242 /// or class type construction ("ClassType(x,y,z)")
1243 /// or creation of a value-initialized type ("int()").
1245 Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo,
1246 SourceLocation LParenLoc,
1248 SourceLocation RParenLoc) {
1249 QualType Ty = TInfo->getType();
1250 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc();
1252 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(Exprs)) {
1253 return CXXUnresolvedConstructExpr::Create(Context, TInfo, LParenLoc, Exprs,
1257 bool ListInitialization = LParenLoc.isInvalid();
1258 assert((!ListInitialization || (Exprs.size() == 1 && isa<InitListExpr>(Exprs[0])))
1259 && "List initialization must have initializer list as expression.");
1260 SourceRange FullRange = SourceRange(TyBeginLoc,
1261 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc);
1263 // C++ [expr.type.conv]p1:
1264 // If the expression list is a single expression, the type conversion
1265 // expression is equivalent (in definedness, and if defined in meaning) to the
1266 // corresponding cast expression.
1267 if (Exprs.size() == 1 && !ListInitialization) {
1268 Expr *Arg = Exprs[0];
1269 return BuildCXXFunctionalCastExpr(TInfo, LParenLoc, Arg, RParenLoc);
1272 // C++14 [expr.type.conv]p2: The expression T(), where T is a
1273 // simple-type-specifier or typename-specifier for a non-array complete
1274 // object type or the (possibly cv-qualified) void type, creates a prvalue
1275 // of the specified type, whose value is that produced by value-initializing
1276 // an object of type T.
1277 QualType ElemTy = Ty;
1278 if (Ty->isArrayType()) {
1279 if (!ListInitialization)
1280 return ExprError(Diag(TyBeginLoc,
1281 diag::err_value_init_for_array_type) << FullRange);
1282 ElemTy = Context.getBaseElementType(Ty);
1285 if (!ListInitialization && Ty->isFunctionType())
1286 return ExprError(Diag(TyBeginLoc, diag::err_value_init_for_function_type)
1289 if (!Ty->isVoidType() &&
1290 RequireCompleteType(TyBeginLoc, ElemTy,
1291 diag::err_invalid_incomplete_type_use, FullRange))
1294 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo);
1295 InitializationKind Kind =
1296 Exprs.size() ? ListInitialization
1297 ? InitializationKind::CreateDirectList(TyBeginLoc)
1298 : InitializationKind::CreateDirect(TyBeginLoc, LParenLoc, RParenLoc)
1299 : InitializationKind::CreateValue(TyBeginLoc, LParenLoc, RParenLoc);
1300 InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
1301 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Exprs);
1303 if (Result.isInvalid() || !ListInitialization)
1306 Expr *Inner = Result.get();
1307 if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Inner))
1308 Inner = BTE->getSubExpr();
1309 if (!isa<CXXTemporaryObjectExpr>(Inner)) {
1310 // If we created a CXXTemporaryObjectExpr, that node also represents the
1311 // functional cast. Otherwise, create an explicit cast to represent
1312 // the syntactic form of a functional-style cast that was used here.
1314 // FIXME: Creating a CXXFunctionalCastExpr around a CXXConstructExpr
1315 // would give a more consistent AST representation than using a
1316 // CXXTemporaryObjectExpr. It's also weird that the functional cast
1317 // is sometimes handled by initialization and sometimes not.
1318 QualType ResultType = Result.get()->getType();
1319 Result = CXXFunctionalCastExpr::Create(
1320 Context, ResultType, Expr::getValueKindForType(TInfo->getType()), TInfo,
1321 CK_NoOp, Result.get(), /*Path=*/nullptr, LParenLoc, RParenLoc);
1327 /// \brief Determine whether the given function is a non-placement
1328 /// deallocation function.
1329 static bool isNonPlacementDeallocationFunction(Sema &S, FunctionDecl *FD) {
1330 if (FD->isInvalidDecl())
1333 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD))
1334 return Method->isUsualDeallocationFunction();
1336 if (FD->getOverloadedOperator() != OO_Delete &&
1337 FD->getOverloadedOperator() != OO_Array_Delete)
1340 unsigned UsualParams = 1;
1342 if (S.getLangOpts().SizedDeallocation && UsualParams < FD->getNumParams() &&
1343 S.Context.hasSameUnqualifiedType(
1344 FD->getParamDecl(UsualParams)->getType(),
1345 S.Context.getSizeType()))
1348 if (S.getLangOpts().AlignedAllocation && UsualParams < FD->getNumParams() &&
1349 S.Context.hasSameUnqualifiedType(
1350 FD->getParamDecl(UsualParams)->getType(),
1351 S.Context.getTypeDeclType(S.getStdAlignValT())))
1354 return UsualParams == FD->getNumParams();
1358 struct UsualDeallocFnInfo {
1359 UsualDeallocFnInfo() : Found(), FD(nullptr) {}
1360 UsualDeallocFnInfo(Sema &S, DeclAccessPair Found)
1361 : Found(Found), FD(dyn_cast<FunctionDecl>(Found->getUnderlyingDecl())),
1362 HasSizeT(false), HasAlignValT(false), CUDAPref(Sema::CFP_Native) {
1363 // A function template declaration is never a usual deallocation function.
1366 if (FD->getNumParams() == 3)
1367 HasAlignValT = HasSizeT = true;
1368 else if (FD->getNumParams() == 2) {
1369 HasSizeT = FD->getParamDecl(1)->getType()->isIntegerType();
1370 HasAlignValT = !HasSizeT;
1373 // In CUDA, determine how much we'd like / dislike to call this.
1374 if (S.getLangOpts().CUDA)
1375 if (auto *Caller = dyn_cast<FunctionDecl>(S.CurContext))
1376 CUDAPref = S.IdentifyCUDAPreference(Caller, FD);
1379 operator bool() const { return FD; }
1381 bool isBetterThan(const UsualDeallocFnInfo &Other, bool WantSize,
1382 bool WantAlign) const {
1383 // C++17 [expr.delete]p10:
1384 // If the type has new-extended alignment, a function with a parameter
1385 // of type std::align_val_t is preferred; otherwise a function without
1386 // such a parameter is preferred
1387 if (HasAlignValT != Other.HasAlignValT)
1388 return HasAlignValT == WantAlign;
1390 if (HasSizeT != Other.HasSizeT)
1391 return HasSizeT == WantSize;
1393 // Use CUDA call preference as a tiebreaker.
1394 return CUDAPref > Other.CUDAPref;
1397 DeclAccessPair Found;
1399 bool HasSizeT, HasAlignValT;
1400 Sema::CUDAFunctionPreference CUDAPref;
1404 /// Determine whether a type has new-extended alignment. This may be called when
1405 /// the type is incomplete (for a delete-expression with an incomplete pointee
1406 /// type), in which case it will conservatively return false if the alignment is
1408 static bool hasNewExtendedAlignment(Sema &S, QualType AllocType) {
1409 return S.getLangOpts().AlignedAllocation &&
1410 S.getASTContext().getTypeAlignIfKnown(AllocType) >
1411 S.getASTContext().getTargetInfo().getNewAlign();
1414 /// Select the correct "usual" deallocation function to use from a selection of
1415 /// deallocation functions (either global or class-scope).
1416 static UsualDeallocFnInfo resolveDeallocationOverload(
1417 Sema &S, LookupResult &R, bool WantSize, bool WantAlign,
1418 llvm::SmallVectorImpl<UsualDeallocFnInfo> *BestFns = nullptr) {
1419 UsualDeallocFnInfo Best;
1421 for (auto I = R.begin(), E = R.end(); I != E; ++I) {
1422 UsualDeallocFnInfo Info(S, I.getPair());
1423 if (!Info || !isNonPlacementDeallocationFunction(S, Info.FD) ||
1424 Info.CUDAPref == Sema::CFP_Never)
1430 BestFns->push_back(Info);
1434 if (Best.isBetterThan(Info, WantSize, WantAlign))
1437 // If more than one preferred function is found, all non-preferred
1438 // functions are eliminated from further consideration.
1439 if (BestFns && Info.isBetterThan(Best, WantSize, WantAlign))
1444 BestFns->push_back(Info);
1450 /// Determine whether a given type is a class for which 'delete[]' would call
1451 /// a member 'operator delete[]' with a 'size_t' parameter. This implies that
1452 /// we need to store the array size (even if the type is
1453 /// trivially-destructible).
1454 static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc,
1455 QualType allocType) {
1456 const RecordType *record =
1457 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>();
1458 if (!record) return false;
1460 // Try to find an operator delete[] in class scope.
1462 DeclarationName deleteName =
1463 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete);
1464 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName);
1465 S.LookupQualifiedName(ops, record->getDecl());
1467 // We're just doing this for information.
1468 ops.suppressDiagnostics();
1470 // Very likely: there's no operator delete[].
1471 if (ops.empty()) return false;
1473 // If it's ambiguous, it should be illegal to call operator delete[]
1474 // on this thing, so it doesn't matter if we allocate extra space or not.
1475 if (ops.isAmbiguous()) return false;
1477 // C++17 [expr.delete]p10:
1478 // If the deallocation functions have class scope, the one without a
1479 // parameter of type std::size_t is selected.
1480 auto Best = resolveDeallocationOverload(
1481 S, ops, /*WantSize*/false,
1482 /*WantAlign*/hasNewExtendedAlignment(S, allocType));
1483 return Best && Best.HasSizeT;
1486 /// \brief Parsed a C++ 'new' expression (C++ 5.3.4).
1489 /// @code new (memory) int[size][4] @endcode
1491 /// @code ::new Foo(23, "hello") @endcode
1493 /// \param StartLoc The first location of the expression.
1494 /// \param UseGlobal True if 'new' was prefixed with '::'.
1495 /// \param PlacementLParen Opening paren of the placement arguments.
1496 /// \param PlacementArgs Placement new arguments.
1497 /// \param PlacementRParen Closing paren of the placement arguments.
1498 /// \param TypeIdParens If the type is in parens, the source range.
1499 /// \param D The type to be allocated, as well as array dimensions.
1500 /// \param Initializer The initializing expression or initializer-list, or null
1501 /// if there is none.
1503 Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
1504 SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
1505 SourceLocation PlacementRParen, SourceRange TypeIdParens,
1506 Declarator &D, Expr *Initializer) {
1507 Expr *ArraySize = nullptr;
1508 // If the specified type is an array, unwrap it and save the expression.
1509 if (D.getNumTypeObjects() > 0 &&
1510 D.getTypeObject(0).Kind == DeclaratorChunk::Array) {
1511 DeclaratorChunk &Chunk = D.getTypeObject(0);
1512 if (D.getDeclSpec().containsPlaceholderType())
1513 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto)
1514 << D.getSourceRange());
1515 if (Chunk.Arr.hasStatic)
1516 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
1517 << D.getSourceRange());
1518 if (!Chunk.Arr.NumElts)
1519 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
1520 << D.getSourceRange());
1522 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
1523 D.DropFirstTypeObject();
1526 // Every dimension shall be of constant size.
1528 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
1529 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array)
1532 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr;
1533 if (Expr *NumElts = (Expr *)Array.NumElts) {
1534 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
1535 if (getLangOpts().CPlusPlus14) {
1536 // C++1y [expr.new]p6: Every constant-expression in a noptr-new-declarator
1537 // shall be a converted constant expression (5.19) of type std::size_t
1538 // and shall evaluate to a strictly positive value.
1539 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
1540 assert(IntWidth && "Builtin type of size 0?");
1541 llvm::APSInt Value(IntWidth);
1543 = CheckConvertedConstantExpression(NumElts, Context.getSizeType(), Value,
1548 = VerifyIntegerConstantExpression(NumElts, nullptr,
1549 diag::err_new_array_nonconst)
1559 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/nullptr);
1560 QualType AllocType = TInfo->getType();
1561 if (D.isInvalidType())
1564 SourceRange DirectInitRange;
1565 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) {
1566 DirectInitRange = List->getSourceRange();
1567 // Handle errors like: new int a({0})
1568 if (List->getNumExprs() == 1 &&
1569 !canInitializeWithParenthesizedList(AllocType))
1570 if (auto IList = dyn_cast<InitListExpr>(List->getExpr(0))) {
1571 Diag(TInfo->getTypeLoc().getLocStart(), diag::err_list_init_in_parens)
1572 << AllocType << List->getSourceRange()
1573 << FixItHint::CreateRemoval(List->getLocStart())
1574 << FixItHint::CreateRemoval(List->getLocEnd());
1575 DirectInitRange = SourceRange();
1576 Initializer = IList;
1580 return BuildCXXNew(SourceRange(StartLoc, D.getLocEnd()), UseGlobal,
1592 static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style,
1596 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init))
1597 return PLE->getNumExprs() == 0;
1598 if (isa<ImplicitValueInitExpr>(Init))
1600 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init))
1601 return !CCE->isListInitialization() &&
1602 CCE->getConstructor()->isDefaultConstructor();
1603 else if (Style == CXXNewExpr::ListInit) {
1604 assert(isa<InitListExpr>(Init) &&
1605 "Shouldn't create list CXXConstructExprs for arrays.");
1612 Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
1613 SourceLocation PlacementLParen,
1614 MultiExprArg PlacementArgs,
1615 SourceLocation PlacementRParen,
1616 SourceRange TypeIdParens,
1618 TypeSourceInfo *AllocTypeInfo,
1620 SourceRange DirectInitRange,
1621 Expr *Initializer) {
1622 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange();
1623 SourceLocation StartLoc = Range.getBegin();
1625 CXXNewExpr::InitializationStyle initStyle;
1626 if (DirectInitRange.isValid()) {
1627 assert(Initializer && "Have parens but no initializer.");
1628 initStyle = CXXNewExpr::CallInit;
1629 } else if (Initializer && isa<InitListExpr>(Initializer))
1630 initStyle = CXXNewExpr::ListInit;
1632 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) ||
1633 isa<CXXConstructExpr>(Initializer)) &&
1634 "Initializer expression that cannot have been implicitly created.");
1635 initStyle = CXXNewExpr::NoInit;
1638 Expr **Inits = &Initializer;
1639 unsigned NumInits = Initializer ? 1 : 0;
1640 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) {
1641 assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init");
1642 Inits = List->getExprs();
1643 NumInits = List->getNumExprs();
1646 // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
1647 if (AllocType->isUndeducedType()) {
1648 if (initStyle == CXXNewExpr::NoInit || NumInits == 0)
1649 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg)
1650 << AllocType << TypeRange);
1651 if (initStyle == CXXNewExpr::ListInit ||
1652 (NumInits == 1 && isa<InitListExpr>(Inits[0])))
1653 return ExprError(Diag(Inits[0]->getLocStart(),
1654 diag::err_auto_new_list_init)
1655 << AllocType << TypeRange);
1657 Expr *FirstBad = Inits[1];
1658 return ExprError(Diag(FirstBad->getLocStart(),
1659 diag::err_auto_new_ctor_multiple_expressions)
1660 << AllocType << TypeRange);
1662 Expr *Deduce = Inits[0];
1663 QualType DeducedType;
1664 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed)
1665 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure)
1666 << AllocType << Deduce->getType()
1667 << TypeRange << Deduce->getSourceRange());
1668 if (DeducedType.isNull())
1670 AllocType = DeducedType;
1673 // Per C++0x [expr.new]p5, the type being constructed may be a
1674 // typedef of an array type.
1676 if (const ConstantArrayType *Array
1677 = Context.getAsConstantArrayType(AllocType)) {
1678 ArraySize = IntegerLiteral::Create(Context, Array->getSize(),
1679 Context.getSizeType(),
1680 TypeRange.getEnd());
1681 AllocType = Array->getElementType();
1685 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange))
1688 if (initStyle == CXXNewExpr::ListInit &&
1689 isStdInitializerList(AllocType, nullptr)) {
1690 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(),
1691 diag::warn_dangling_std_initializer_list)
1692 << /*at end of FE*/0 << Inits[0]->getSourceRange();
1695 // In ARC, infer 'retaining' for the allocated
1696 if (getLangOpts().ObjCAutoRefCount &&
1697 AllocType.getObjCLifetime() == Qualifiers::OCL_None &&
1698 AllocType->isObjCLifetimeType()) {
1699 AllocType = Context.getLifetimeQualifiedType(AllocType,
1700 AllocType->getObjCARCImplicitLifetime());
1703 QualType ResultType = Context.getPointerType(AllocType);
1705 if (ArraySize && ArraySize->getType()->isNonOverloadPlaceholderType()) {
1706 ExprResult result = CheckPlaceholderExpr(ArraySize);
1707 if (result.isInvalid()) return ExprError();
1708 ArraySize = result.get();
1710 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have
1711 // integral or enumeration type with a non-negative value."
1712 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped
1713 // enumeration type, or a class type for which a single non-explicit
1714 // conversion function to integral or unscoped enumeration type exists.
1715 // C++1y [expr.new]p6: The expression [...] is implicitly converted to
1717 llvm::Optional<uint64_t> KnownArraySize;
1718 if (ArraySize && !ArraySize->isTypeDependent()) {
1719 ExprResult ConvertedSize;
1720 if (getLangOpts().CPlusPlus14) {
1721 assert(Context.getTargetInfo().getIntWidth() && "Builtin type of size 0?");
1723 ConvertedSize = PerformImplicitConversion(ArraySize, Context.getSizeType(),
1726 if (!ConvertedSize.isInvalid() &&
1727 ArraySize->getType()->getAs<RecordType>())
1728 // Diagnose the compatibility of this conversion.
1729 Diag(StartLoc, diag::warn_cxx98_compat_array_size_conversion)
1730 << ArraySize->getType() << 0 << "'size_t'";
1732 class SizeConvertDiagnoser : public ICEConvertDiagnoser {
1737 SizeConvertDiagnoser(Expr *ArraySize)
1738 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false, false, false),
1739 ArraySize(ArraySize) {}
1741 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
1742 QualType T) override {
1743 return S.Diag(Loc, diag::err_array_size_not_integral)
1744 << S.getLangOpts().CPlusPlus11 << T;
1747 SemaDiagnosticBuilder diagnoseIncomplete(
1748 Sema &S, SourceLocation Loc, QualType T) override {
1749 return S.Diag(Loc, diag::err_array_size_incomplete_type)
1750 << T << ArraySize->getSourceRange();
1753 SemaDiagnosticBuilder diagnoseExplicitConv(
1754 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
1755 return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy;
1758 SemaDiagnosticBuilder noteExplicitConv(
1759 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1760 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1761 << ConvTy->isEnumeralType() << ConvTy;
1764 SemaDiagnosticBuilder diagnoseAmbiguous(
1765 Sema &S, SourceLocation Loc, QualType T) override {
1766 return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T;
1769 SemaDiagnosticBuilder noteAmbiguous(
1770 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1771 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1772 << ConvTy->isEnumeralType() << ConvTy;
1775 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
1777 QualType ConvTy) override {
1779 S.getLangOpts().CPlusPlus11
1780 ? diag::warn_cxx98_compat_array_size_conversion
1781 : diag::ext_array_size_conversion)
1782 << T << ConvTy->isEnumeralType() << ConvTy;
1784 } SizeDiagnoser(ArraySize);
1786 ConvertedSize = PerformContextualImplicitConversion(StartLoc, ArraySize,
1789 if (ConvertedSize.isInvalid())
1792 ArraySize = ConvertedSize.get();
1793 QualType SizeType = ArraySize->getType();
1795 if (!SizeType->isIntegralOrUnscopedEnumerationType())
1798 // C++98 [expr.new]p7:
1799 // The expression in a direct-new-declarator shall have integral type
1800 // with a non-negative value.
1802 // Let's see if this is a constant < 0. If so, we reject it out of hand,
1803 // per CWG1464. Otherwise, if it's not a constant, we must have an
1804 // unparenthesized array type.
1805 if (!ArraySize->isValueDependent()) {
1807 // We've already performed any required implicit conversion to integer or
1808 // unscoped enumeration type.
1809 // FIXME: Per CWG1464, we are required to check the value prior to
1810 // converting to size_t. This will never find a negative array size in
1811 // C++14 onwards, because Value is always unsigned here!
1812 if (ArraySize->isIntegerConstantExpr(Value, Context)) {
1813 if (Value.isSigned() && Value.isNegative()) {
1814 return ExprError(Diag(ArraySize->getLocStart(),
1815 diag::err_typecheck_negative_array_size)
1816 << ArraySize->getSourceRange());
1819 if (!AllocType->isDependentType()) {
1820 unsigned ActiveSizeBits =
1821 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value);
1822 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context))
1823 return ExprError(Diag(ArraySize->getLocStart(),
1824 diag::err_array_too_large)
1825 << Value.toString(10)
1826 << ArraySize->getSourceRange());
1829 KnownArraySize = Value.getZExtValue();
1830 } else if (TypeIdParens.isValid()) {
1831 // Can't have dynamic array size when the type-id is in parentheses.
1832 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst)
1833 << ArraySize->getSourceRange()
1834 << FixItHint::CreateRemoval(TypeIdParens.getBegin())
1835 << FixItHint::CreateRemoval(TypeIdParens.getEnd());
1837 TypeIdParens = SourceRange();
1841 // Note that we do *not* convert the argument in any way. It can
1842 // be signed, larger than size_t, whatever.
1845 FunctionDecl *OperatorNew = nullptr;
1846 FunctionDecl *OperatorDelete = nullptr;
1847 unsigned Alignment =
1848 AllocType->isDependentType() ? 0 : Context.getTypeAlign(AllocType);
1849 unsigned NewAlignment = Context.getTargetInfo().getNewAlign();
1850 bool PassAlignment = getLangOpts().AlignedAllocation &&
1851 Alignment > NewAlignment;
1853 if (!AllocType->isDependentType() &&
1854 !Expr::hasAnyTypeDependentArguments(PlacementArgs) &&
1855 FindAllocationFunctions(StartLoc,
1856 SourceRange(PlacementLParen, PlacementRParen),
1857 UseGlobal, AllocType, ArraySize, PassAlignment,
1858 PlacementArgs, OperatorNew, OperatorDelete))
1861 // If this is an array allocation, compute whether the usual array
1862 // deallocation function for the type has a size_t parameter.
1863 bool UsualArrayDeleteWantsSize = false;
1864 if (ArraySize && !AllocType->isDependentType())
1865 UsualArrayDeleteWantsSize =
1866 doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType);
1868 SmallVector<Expr *, 8> AllPlaceArgs;
1870 const FunctionProtoType *Proto =
1871 OperatorNew->getType()->getAs<FunctionProtoType>();
1872 VariadicCallType CallType = Proto->isVariadic() ? VariadicFunction
1873 : VariadicDoesNotApply;
1875 // We've already converted the placement args, just fill in any default
1876 // arguments. Skip the first parameter because we don't have a corresponding
1877 // argument. Skip the second parameter too if we're passing in the
1878 // alignment; we've already filled it in.
1879 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, Proto,
1880 PassAlignment ? 2 : 1, PlacementArgs,
1881 AllPlaceArgs, CallType))
1884 if (!AllPlaceArgs.empty())
1885 PlacementArgs = AllPlaceArgs;
1887 // FIXME: This is wrong: PlacementArgs misses out the first (size) argument.
1888 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, PlacementArgs);
1890 // FIXME: Missing call to CheckFunctionCall or equivalent
1892 // Warn if the type is over-aligned and is being allocated by (unaligned)
1893 // global operator new.
1894 if (PlacementArgs.empty() && !PassAlignment &&
1895 (OperatorNew->isImplicit() ||
1896 (OperatorNew->getLocStart().isValid() &&
1897 getSourceManager().isInSystemHeader(OperatorNew->getLocStart())))) {
1898 if (Alignment > NewAlignment)
1899 Diag(StartLoc, diag::warn_overaligned_type)
1901 << unsigned(Alignment / Context.getCharWidth())
1902 << unsigned(NewAlignment / Context.getCharWidth());
1906 // Array 'new' can't have any initializers except empty parentheses.
1907 // Initializer lists are also allowed, in C++11. Rely on the parser for the
1908 // dialect distinction.
1909 if (ArraySize && !isLegalArrayNewInitializer(initStyle, Initializer)) {
1910 SourceRange InitRange(Inits[0]->getLocStart(),
1911 Inits[NumInits - 1]->getLocEnd());
1912 Diag(StartLoc, diag::err_new_array_init_args) << InitRange;
1916 // If we can perform the initialization, and we've not already done so,
1918 if (!AllocType->isDependentType() &&
1919 !Expr::hasAnyTypeDependentArguments(
1920 llvm::makeArrayRef(Inits, NumInits))) {
1921 // The type we initialize is the complete type, including the array bound.
1924 InitType = Context.getConstantArrayType(
1925 AllocType, llvm::APInt(Context.getTypeSize(Context.getSizeType()),
1927 ArrayType::Normal, 0);
1930 Context.getIncompleteArrayType(AllocType, ArrayType::Normal, 0);
1932 InitType = AllocType;
1934 // C++11 [expr.new]p15:
1935 // A new-expression that creates an object of type T initializes that
1936 // object as follows:
1937 InitializationKind Kind
1938 // - If the new-initializer is omitted, the object is default-
1939 // initialized (8.5); if no initialization is performed,
1940 // the object has indeterminate value
1941 = initStyle == CXXNewExpr::NoInit
1942 ? InitializationKind::CreateDefault(TypeRange.getBegin())
1943 // - Otherwise, the new-initializer is interpreted according to the
1944 // initialization rules of 8.5 for direct-initialization.
1945 : initStyle == CXXNewExpr::ListInit
1946 ? InitializationKind::CreateDirectList(TypeRange.getBegin())
1947 : InitializationKind::CreateDirect(TypeRange.getBegin(),
1948 DirectInitRange.getBegin(),
1949 DirectInitRange.getEnd());
1951 InitializedEntity Entity
1952 = InitializedEntity::InitializeNew(StartLoc, InitType);
1953 InitializationSequence InitSeq(*this, Entity, Kind,
1954 MultiExprArg(Inits, NumInits));
1955 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind,
1956 MultiExprArg(Inits, NumInits));
1957 if (FullInit.isInvalid())
1960 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because
1961 // we don't want the initialized object to be destructed.
1962 // FIXME: We should not create these in the first place.
1963 if (CXXBindTemporaryExpr *Binder =
1964 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get()))
1965 FullInit = Binder->getSubExpr();
1967 Initializer = FullInit.get();
1970 // Mark the new and delete operators as referenced.
1972 if (DiagnoseUseOfDecl(OperatorNew, StartLoc))
1974 MarkFunctionReferenced(StartLoc, OperatorNew);
1976 if (OperatorDelete) {
1977 if (DiagnoseUseOfDecl(OperatorDelete, StartLoc))
1979 MarkFunctionReferenced(StartLoc, OperatorDelete);
1982 // C++0x [expr.new]p17:
1983 // If the new expression creates an array of objects of class type,
1984 // access and ambiguity control are done for the destructor.
1985 QualType BaseAllocType = Context.getBaseElementType(AllocType);
1986 if (ArraySize && !BaseAllocType->isDependentType()) {
1987 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) {
1988 if (CXXDestructorDecl *dtor = LookupDestructor(
1989 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) {
1990 MarkFunctionReferenced(StartLoc, dtor);
1991 CheckDestructorAccess(StartLoc, dtor,
1992 PDiag(diag::err_access_dtor)
1994 if (DiagnoseUseOfDecl(dtor, StartLoc))
2000 return new (Context)
2001 CXXNewExpr(Context, UseGlobal, OperatorNew, OperatorDelete, PassAlignment,
2002 UsualArrayDeleteWantsSize, PlacementArgs, TypeIdParens,
2003 ArraySize, initStyle, Initializer, ResultType, AllocTypeInfo,
2004 Range, DirectInitRange);
2007 /// \brief Checks that a type is suitable as the allocated type
2008 /// in a new-expression.
2009 bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc,
2011 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
2012 // abstract class type or array thereof.
2013 if (AllocType->isFunctionType())
2014 return Diag(Loc, diag::err_bad_new_type)
2015 << AllocType << 0 << R;
2016 else if (AllocType->isReferenceType())
2017 return Diag(Loc, diag::err_bad_new_type)
2018 << AllocType << 1 << R;
2019 else if (!AllocType->isDependentType() &&
2020 RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R))
2022 else if (RequireNonAbstractType(Loc, AllocType,
2023 diag::err_allocation_of_abstract_type))
2025 else if (AllocType->isVariablyModifiedType())
2026 return Diag(Loc, diag::err_variably_modified_new_type)
2028 else if (unsigned AddressSpace = AllocType.getAddressSpace())
2029 return Diag(Loc, diag::err_address_space_qualified_new)
2030 << AllocType.getUnqualifiedType() << AddressSpace;
2031 else if (getLangOpts().ObjCAutoRefCount) {
2032 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) {
2033 QualType BaseAllocType = Context.getBaseElementType(AT);
2034 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None &&
2035 BaseAllocType->isObjCLifetimeType())
2036 return Diag(Loc, diag::err_arc_new_array_without_ownership)
2045 resolveAllocationOverload(Sema &S, LookupResult &R, SourceRange Range,
2046 SmallVectorImpl<Expr *> &Args, bool &PassAlignment,
2047 FunctionDecl *&Operator,
2048 OverloadCandidateSet *AlignedCandidates = nullptr,
2049 Expr *AlignArg = nullptr) {
2050 OverloadCandidateSet Candidates(R.getNameLoc(),
2051 OverloadCandidateSet::CSK_Normal);
2052 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
2053 Alloc != AllocEnd; ++Alloc) {
2054 // Even member operator new/delete are implicitly treated as
2055 // static, so don't use AddMemberCandidate.
2056 NamedDecl *D = (*Alloc)->getUnderlyingDecl();
2058 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
2059 S.AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(),
2060 /*ExplicitTemplateArgs=*/nullptr, Args,
2062 /*SuppressUserConversions=*/false);
2066 FunctionDecl *Fn = cast<FunctionDecl>(D);
2067 S.AddOverloadCandidate(Fn, Alloc.getPair(), Args, Candidates,
2068 /*SuppressUserConversions=*/false);
2071 // Do the resolution.
2072 OverloadCandidateSet::iterator Best;
2073 switch (Candidates.BestViableFunction(S, R.getNameLoc(), Best)) {
2076 FunctionDecl *FnDecl = Best->Function;
2077 if (S.CheckAllocationAccess(R.getNameLoc(), Range, R.getNamingClass(),
2078 Best->FoundDecl) == Sema::AR_inaccessible)
2085 case OR_No_Viable_Function:
2086 // C++17 [expr.new]p13:
2087 // If no matching function is found and the allocated object type has
2088 // new-extended alignment, the alignment argument is removed from the
2089 // argument list, and overload resolution is performed again.
2090 if (PassAlignment) {
2091 PassAlignment = false;
2093 Args.erase(Args.begin() + 1);
2094 return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2095 Operator, &Candidates, AlignArg);
2098 // MSVC will fall back on trying to find a matching global operator new
2099 // if operator new[] cannot be found. Also, MSVC will leak by not
2100 // generating a call to operator delete or operator delete[], but we
2101 // will not replicate that bug.
2102 // FIXME: Find out how this interacts with the std::align_val_t fallback
2103 // once MSVC implements it.
2104 if (R.getLookupName().getCXXOverloadedOperator() == OO_Array_New &&
2105 S.Context.getLangOpts().MSVCCompat) {
2107 R.setLookupName(S.Context.DeclarationNames.getCXXOperatorName(OO_New));
2108 S.LookupQualifiedName(R, S.Context.getTranslationUnitDecl());
2109 // FIXME: This will give bad diagnostics pointing at the wrong functions.
2110 return resolveAllocationOverload(S, R, Range, Args, PassAlignment,
2114 S.Diag(R.getNameLoc(), diag::err_ovl_no_viable_function_in_call)
2115 << R.getLookupName() << Range;
2117 // If we have aligned candidates, only note the align_val_t candidates
2118 // from AlignedCandidates and the non-align_val_t candidates from
2120 if (AlignedCandidates) {
2121 auto IsAligned = [](OverloadCandidate &C) {
2122 return C.Function->getNumParams() > 1 &&
2123 C.Function->getParamDecl(1)->getType()->isAlignValT();
2125 auto IsUnaligned = [&](OverloadCandidate &C) { return !IsAligned(C); };
2127 // This was an overaligned allocation, so list the aligned candidates
2129 Args.insert(Args.begin() + 1, AlignArg);
2130 AlignedCandidates->NoteCandidates(S, OCD_AllCandidates, Args, "",
2131 R.getNameLoc(), IsAligned);
2132 Args.erase(Args.begin() + 1);
2133 Candidates.NoteCandidates(S, OCD_AllCandidates, Args, "", R.getNameLoc(),
2136 Candidates.NoteCandidates(S, OCD_AllCandidates, Args);
2141 S.Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call)
2142 << R.getLookupName() << Range;
2143 Candidates.NoteCandidates(S, OCD_ViableCandidates, Args);
2147 S.Diag(R.getNameLoc(), diag::err_ovl_deleted_call)
2148 << Best->Function->isDeleted()
2149 << R.getLookupName()
2150 << S.getDeletedOrUnavailableSuffix(Best->Function)
2152 Candidates.NoteCandidates(S, OCD_AllCandidates, Args);
2156 llvm_unreachable("Unreachable, bad result from BestViableFunction");
2160 /// FindAllocationFunctions - Finds the overloads of operator new and delete
2161 /// that are appropriate for the allocation.
2162 bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
2163 bool UseGlobal, QualType AllocType,
2164 bool IsArray, bool &PassAlignment,
2165 MultiExprArg PlaceArgs,
2166 FunctionDecl *&OperatorNew,
2167 FunctionDecl *&OperatorDelete) {
2168 // --- Choosing an allocation function ---
2169 // C++ 5.3.4p8 - 14 & 18
2170 // 1) If UseGlobal is true, only look in the global scope. Else, also look
2171 // in the scope of the allocated class.
2172 // 2) If an array size is given, look for operator new[], else look for
2174 // 3) The first argument is always size_t. Append the arguments from the
2177 SmallVector<Expr*, 8> AllocArgs;
2178 AllocArgs.reserve((PassAlignment ? 2 : 1) + PlaceArgs.size());
2180 // We don't care about the actual value of these arguments.
2181 // FIXME: Should the Sema create the expression and embed it in the syntax
2182 // tree? Or should the consumer just recalculate the value?
2183 // FIXME: Using a dummy value will interact poorly with attribute enable_if.
2184 IntegerLiteral Size(Context, llvm::APInt::getNullValue(
2185 Context.getTargetInfo().getPointerWidth(0)),
2186 Context.getSizeType(),
2188 AllocArgs.push_back(&Size);
2190 QualType AlignValT = Context.VoidTy;
2191 if (PassAlignment) {
2192 DeclareGlobalNewDelete();
2193 AlignValT = Context.getTypeDeclType(getStdAlignValT());
2195 CXXScalarValueInitExpr Align(AlignValT, nullptr, SourceLocation());
2197 AllocArgs.push_back(&Align);
2199 AllocArgs.insert(AllocArgs.end(), PlaceArgs.begin(), PlaceArgs.end());
2201 // C++ [expr.new]p8:
2202 // If the allocated type is a non-array type, the allocation
2203 // function's name is operator new and the deallocation function's
2204 // name is operator delete. If the allocated type is an array
2205 // type, the allocation function's name is operator new[] and the
2206 // deallocation function's name is operator delete[].
2207 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName(
2208 IsArray ? OO_Array_New : OO_New);
2210 QualType AllocElemType = Context.getBaseElementType(AllocType);
2212 // Find the allocation function.
2214 LookupResult R(*this, NewName, StartLoc, LookupOrdinaryName);
2216 // C++1z [expr.new]p9:
2217 // If the new-expression begins with a unary :: operator, the allocation
2218 // function's name is looked up in the global scope. Otherwise, if the
2219 // allocated type is a class type T or array thereof, the allocation
2220 // function's name is looked up in the scope of T.
2221 if (AllocElemType->isRecordType() && !UseGlobal)
2222 LookupQualifiedName(R, AllocElemType->getAsCXXRecordDecl());
2224 // We can see ambiguity here if the allocation function is found in
2225 // multiple base classes.
2226 if (R.isAmbiguous())
2229 // If this lookup fails to find the name, or if the allocated type is not
2230 // a class type, the allocation function's name is looked up in the
2233 LookupQualifiedName(R, Context.getTranslationUnitDecl());
2235 assert(!R.empty() && "implicitly declared allocation functions not found");
2236 assert(!R.isAmbiguous() && "global allocation functions are ambiguous");
2238 // We do our own custom access checks below.
2239 R.suppressDiagnostics();
2241 if (resolveAllocationOverload(*this, R, Range, AllocArgs, PassAlignment,
2246 // We don't need an operator delete if we're running under -fno-exceptions.
2247 if (!getLangOpts().Exceptions) {
2248 OperatorDelete = nullptr;
2252 // Note, the name of OperatorNew might have been changed from array to
2253 // non-array by resolveAllocationOverload.
2254 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
2255 OperatorNew->getDeclName().getCXXOverloadedOperator() == OO_Array_New
2259 // C++ [expr.new]p19:
2261 // If the new-expression begins with a unary :: operator, the
2262 // deallocation function's name is looked up in the global
2263 // scope. Otherwise, if the allocated type is a class type T or an
2264 // array thereof, the deallocation function's name is looked up in
2265 // the scope of T. If this lookup fails to find the name, or if
2266 // the allocated type is not a class type or array thereof, the
2267 // deallocation function's name is looked up in the global scope.
2268 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName);
2269 if (AllocElemType->isRecordType() && !UseGlobal) {
2271 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl());
2272 LookupQualifiedName(FoundDelete, RD);
2274 if (FoundDelete.isAmbiguous())
2275 return true; // FIXME: clean up expressions?
2277 bool FoundGlobalDelete = FoundDelete.empty();
2278 if (FoundDelete.empty()) {
2279 DeclareGlobalNewDelete();
2280 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2283 FoundDelete.suppressDiagnostics();
2285 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches;
2287 // Whether we're looking for a placement operator delete is dictated
2288 // by whether we selected a placement operator new, not by whether
2289 // we had explicit placement arguments. This matters for things like
2290 // struct A { void *operator new(size_t, int = 0); ... };
2293 // We don't have any definition for what a "placement allocation function"
2294 // is, but we assume it's any allocation function whose
2295 // parameter-declaration-clause is anything other than (size_t).
2297 // FIXME: Should (size_t, std::align_val_t) also be considered non-placement?
2298 // This affects whether an exception from the constructor of an overaligned
2299 // type uses the sized or non-sized form of aligned operator delete.
2300 bool isPlacementNew = !PlaceArgs.empty() || OperatorNew->param_size() != 1 ||
2301 OperatorNew->isVariadic();
2303 if (isPlacementNew) {
2304 // C++ [expr.new]p20:
2305 // A declaration of a placement deallocation function matches the
2306 // declaration of a placement allocation function if it has the
2307 // same number of parameters and, after parameter transformations
2308 // (8.3.5), all parameter types except the first are
2311 // To perform this comparison, we compute the function type that
2312 // the deallocation function should have, and use that type both
2313 // for template argument deduction and for comparison purposes.
2314 QualType ExpectedFunctionType;
2316 const FunctionProtoType *Proto
2317 = OperatorNew->getType()->getAs<FunctionProtoType>();
2319 SmallVector<QualType, 4> ArgTypes;
2320 ArgTypes.push_back(Context.VoidPtrTy);
2321 for (unsigned I = 1, N = Proto->getNumParams(); I < N; ++I)
2322 ArgTypes.push_back(Proto->getParamType(I));
2324 FunctionProtoType::ExtProtoInfo EPI;
2325 // FIXME: This is not part of the standard's rule.
2326 EPI.Variadic = Proto->isVariadic();
2328 ExpectedFunctionType
2329 = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI);
2332 for (LookupResult::iterator D = FoundDelete.begin(),
2333 DEnd = FoundDelete.end();
2335 FunctionDecl *Fn = nullptr;
2336 if (FunctionTemplateDecl *FnTmpl =
2337 dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) {
2338 // Perform template argument deduction to try to match the
2339 // expected function type.
2340 TemplateDeductionInfo Info(StartLoc);
2341 if (DeduceTemplateArguments(FnTmpl, nullptr, ExpectedFunctionType, Fn,
2345 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl());
2347 if (Context.hasSameType(adjustCCAndNoReturn(Fn->getType(),
2348 ExpectedFunctionType,
2349 /*AdjustExcpetionSpec*/true),
2350 ExpectedFunctionType))
2351 Matches.push_back(std::make_pair(D.getPair(), Fn));
2354 if (getLangOpts().CUDA)
2355 EraseUnwantedCUDAMatches(dyn_cast<FunctionDecl>(CurContext), Matches);
2357 // C++1y [expr.new]p22:
2358 // For a non-placement allocation function, the normal deallocation
2359 // function lookup is used
2361 // Per [expr.delete]p10, this lookup prefers a member operator delete
2362 // without a size_t argument, but prefers a non-member operator delete
2363 // with a size_t where possible (which it always is in this case).
2364 llvm::SmallVector<UsualDeallocFnInfo, 4> BestDeallocFns;
2365 UsualDeallocFnInfo Selected = resolveDeallocationOverload(
2366 *this, FoundDelete, /*WantSize*/ FoundGlobalDelete,
2367 /*WantAlign*/ hasNewExtendedAlignment(*this, AllocElemType),
2370 Matches.push_back(std::make_pair(Selected.Found, Selected.FD));
2372 // If we failed to select an operator, all remaining functions are viable
2374 for (auto Fn : BestDeallocFns)
2375 Matches.push_back(std::make_pair(Fn.Found, Fn.FD));
2379 // C++ [expr.new]p20:
2380 // [...] If the lookup finds a single matching deallocation
2381 // function, that function will be called; otherwise, no
2382 // deallocation function will be called.
2383 if (Matches.size() == 1) {
2384 OperatorDelete = Matches[0].second;
2386 // C++1z [expr.new]p23:
2387 // If the lookup finds a usual deallocation function (3.7.4.2)
2388 // with a parameter of type std::size_t and that function, considered
2389 // as a placement deallocation function, would have been
2390 // selected as a match for the allocation function, the program
2392 if (getLangOpts().CPlusPlus11 && isPlacementNew &&
2393 isNonPlacementDeallocationFunction(*this, OperatorDelete)) {
2394 UsualDeallocFnInfo Info(*this,
2395 DeclAccessPair::make(OperatorDelete, AS_public));
2396 // Core issue, per mail to core reflector, 2016-10-09:
2397 // If this is a member operator delete, and there is a corresponding
2398 // non-sized member operator delete, this isn't /really/ a sized
2399 // deallocation function, it just happens to have a size_t parameter.
2400 bool IsSizedDelete = Info.HasSizeT;
2401 if (IsSizedDelete && !FoundGlobalDelete) {
2402 auto NonSizedDelete =
2403 resolveDeallocationOverload(*this, FoundDelete, /*WantSize*/false,
2404 /*WantAlign*/Info.HasAlignValT);
2405 if (NonSizedDelete && !NonSizedDelete.HasSizeT &&
2406 NonSizedDelete.HasAlignValT == Info.HasAlignValT)
2407 IsSizedDelete = false;
2410 if (IsSizedDelete) {
2411 SourceRange R = PlaceArgs.empty()
2413 : SourceRange(PlaceArgs.front()->getLocStart(),
2414 PlaceArgs.back()->getLocEnd());
2415 Diag(StartLoc, diag::err_placement_new_non_placement_delete) << R;
2416 if (!OperatorDelete->isImplicit())
2417 Diag(OperatorDelete->getLocation(), diag::note_previous_decl)
2422 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(),
2424 } else if (!Matches.empty()) {
2425 // We found multiple suitable operators. Per [expr.new]p20, that means we
2426 // call no 'operator delete' function, but we should at least warn the user.
2427 // FIXME: Suppress this warning if the construction cannot throw.
2428 Diag(StartLoc, diag::warn_ambiguous_suitable_delete_function_found)
2429 << DeleteName << AllocElemType;
2431 for (auto &Match : Matches)
2432 Diag(Match.second->getLocation(),
2433 diag::note_member_declared_here) << DeleteName;
2439 /// DeclareGlobalNewDelete - Declare the global forms of operator new and
2440 /// delete. These are:
2443 /// void* operator new(std::size_t) throw(std::bad_alloc);
2444 /// void* operator new[](std::size_t) throw(std::bad_alloc);
2445 /// void operator delete(void *) throw();
2446 /// void operator delete[](void *) throw();
2448 /// void* operator new(std::size_t);
2449 /// void* operator new[](std::size_t);
2450 /// void operator delete(void *) noexcept;
2451 /// void operator delete[](void *) noexcept;
2453 /// void* operator new(std::size_t);
2454 /// void* operator new[](std::size_t);
2455 /// void operator delete(void *) noexcept;
2456 /// void operator delete[](void *) noexcept;
2457 /// void operator delete(void *, std::size_t) noexcept;
2458 /// void operator delete[](void *, std::size_t) noexcept;
2460 /// Note that the placement and nothrow forms of new are *not* implicitly
2461 /// declared. Their use requires including \<new\>.
2462 void Sema::DeclareGlobalNewDelete() {
2463 if (GlobalNewDeleteDeclared)
2466 // C++ [basic.std.dynamic]p2:
2467 // [...] The following allocation and deallocation functions (18.4) are
2468 // implicitly declared in global scope in each translation unit of a
2472 // void* operator new(std::size_t) throw(std::bad_alloc);
2473 // void* operator new[](std::size_t) throw(std::bad_alloc);
2474 // void operator delete(void*) throw();
2475 // void operator delete[](void*) throw();
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;
2482 // void* operator new(std::size_t);
2483 // void* operator new[](std::size_t);
2484 // void operator delete(void*) noexcept;
2485 // void operator delete[](void*) noexcept;
2486 // void operator delete(void*, std::size_t) noexcept;
2487 // void operator delete[](void*, std::size_t) noexcept;
2489 // These implicit declarations introduce only the function names operator
2490 // new, operator new[], operator delete, operator delete[].
2492 // Here, we need to refer to std::bad_alloc, so we will implicitly declare
2493 // "std" or "bad_alloc" as necessary to form the exception specification.
2494 // However, we do not make these implicit declarations visible to name
2496 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) {
2497 // The "std::bad_alloc" class has not yet been declared, so build it
2499 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class,
2500 getOrCreateStdNamespace(),
2501 SourceLocation(), SourceLocation(),
2502 &PP.getIdentifierTable().get("bad_alloc"),
2504 getStdBadAlloc()->setImplicit(true);
2506 if (!StdAlignValT && getLangOpts().AlignedAllocation) {
2507 // The "std::align_val_t" enum class has not yet been declared, so build it
2509 auto *AlignValT = EnumDecl::Create(
2510 Context, getOrCreateStdNamespace(), SourceLocation(), SourceLocation(),
2511 &PP.getIdentifierTable().get("align_val_t"), nullptr, true, true, true);
2512 AlignValT->setIntegerType(Context.getSizeType());
2513 AlignValT->setPromotionType(Context.getSizeType());
2514 AlignValT->setImplicit(true);
2515 StdAlignValT = AlignValT;
2518 GlobalNewDeleteDeclared = true;
2520 QualType VoidPtr = Context.getPointerType(Context.VoidTy);
2521 QualType SizeT = Context.getSizeType();
2523 auto DeclareGlobalAllocationFunctions = [&](OverloadedOperatorKind Kind,
2524 QualType Return, QualType Param) {
2525 llvm::SmallVector<QualType, 3> Params;
2526 Params.push_back(Param);
2528 // Create up to four variants of the function (sized/aligned).
2529 bool HasSizedVariant = getLangOpts().SizedDeallocation &&
2530 (Kind == OO_Delete || Kind == OO_Array_Delete);
2531 bool HasAlignedVariant = getLangOpts().AlignedAllocation;
2533 int NumSizeVariants = (HasSizedVariant ? 2 : 1);
2534 int NumAlignVariants = (HasAlignedVariant ? 2 : 1);
2535 for (int Sized = 0; Sized < NumSizeVariants; ++Sized) {
2537 Params.push_back(SizeT);
2539 for (int Aligned = 0; Aligned < NumAlignVariants; ++Aligned) {
2541 Params.push_back(Context.getTypeDeclType(getStdAlignValT()));
2543 DeclareGlobalAllocationFunction(
2544 Context.DeclarationNames.getCXXOperatorName(Kind), Return, Params);
2552 DeclareGlobalAllocationFunctions(OO_New, VoidPtr, SizeT);
2553 DeclareGlobalAllocationFunctions(OO_Array_New, VoidPtr, SizeT);
2554 DeclareGlobalAllocationFunctions(OO_Delete, Context.VoidTy, VoidPtr);
2555 DeclareGlobalAllocationFunctions(OO_Array_Delete, Context.VoidTy, VoidPtr);
2558 /// DeclareGlobalAllocationFunction - Declares a single implicit global
2559 /// allocation function if it doesn't already exist.
2560 void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
2562 ArrayRef<QualType> Params) {
2563 DeclContext *GlobalCtx = Context.getTranslationUnitDecl();
2565 // Check if this function is already declared.
2566 DeclContext::lookup_result R = GlobalCtx->lookup(Name);
2567 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end();
2568 Alloc != AllocEnd; ++Alloc) {
2569 // Only look at non-template functions, as it is the predefined,
2570 // non-templated allocation function we are trying to declare here.
2571 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
2572 if (Func->getNumParams() == Params.size()) {
2573 llvm::SmallVector<QualType, 3> FuncParams;
2574 for (auto *P : Func->parameters())
2575 FuncParams.push_back(
2576 Context.getCanonicalType(P->getType().getUnqualifiedType()));
2577 if (llvm::makeArrayRef(FuncParams) == Params) {
2578 // Make the function visible to name lookup, even if we found it in
2579 // an unimported module. It either is an implicitly-declared global
2580 // allocation function, or is suppressing that function.
2581 Func->setHidden(false);
2588 FunctionProtoType::ExtProtoInfo EPI;
2590 QualType BadAllocType;
2591 bool HasBadAllocExceptionSpec
2592 = (Name.getCXXOverloadedOperator() == OO_New ||
2593 Name.getCXXOverloadedOperator() == OO_Array_New);
2594 if (HasBadAllocExceptionSpec) {
2595 if (!getLangOpts().CPlusPlus11) {
2596 BadAllocType = Context.getTypeDeclType(getStdBadAlloc());
2597 assert(StdBadAlloc && "Must have std::bad_alloc declared");
2598 EPI.ExceptionSpec.Type = EST_Dynamic;
2599 EPI.ExceptionSpec.Exceptions = llvm::makeArrayRef(BadAllocType);
2603 getLangOpts().CPlusPlus11 ? EST_BasicNoexcept : EST_DynamicNone;
2606 auto CreateAllocationFunctionDecl = [&](Attr *ExtraAttr) {
2607 QualType FnType = Context.getFunctionType(Return, Params, EPI);
2608 FunctionDecl *Alloc = FunctionDecl::Create(
2609 Context, GlobalCtx, SourceLocation(), SourceLocation(), Name,
2610 FnType, /*TInfo=*/nullptr, SC_None, false, true);
2611 Alloc->setImplicit();
2613 // Implicit sized deallocation functions always have default visibility.
2615 VisibilityAttr::CreateImplicit(Context, VisibilityAttr::Default));
2617 llvm::SmallVector<ParmVarDecl *, 3> ParamDecls;
2618 for (QualType T : Params) {
2619 ParamDecls.push_back(ParmVarDecl::Create(
2620 Context, Alloc, SourceLocation(), SourceLocation(), nullptr, T,
2621 /*TInfo=*/nullptr, SC_None, nullptr));
2622 ParamDecls.back()->setImplicit();
2624 Alloc->setParams(ParamDecls);
2626 Alloc->addAttr(ExtraAttr);
2627 Context.getTranslationUnitDecl()->addDecl(Alloc);
2628 IdResolver.tryAddTopLevelDecl(Alloc, Name);
2632 CreateAllocationFunctionDecl(nullptr);
2634 // Host and device get their own declaration so each can be
2635 // defined or re-declared independently.
2636 CreateAllocationFunctionDecl(CUDAHostAttr::CreateImplicit(Context));
2637 CreateAllocationFunctionDecl(CUDADeviceAttr::CreateImplicit(Context));
2641 FunctionDecl *Sema::FindUsualDeallocationFunction(SourceLocation StartLoc,
2642 bool CanProvideSize,
2644 DeclarationName Name) {
2645 DeclareGlobalNewDelete();
2647 LookupResult FoundDelete(*this, Name, StartLoc, LookupOrdinaryName);
2648 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2650 // FIXME: It's possible for this to result in ambiguity, through a
2651 // user-declared variadic operator delete or the enable_if attribute. We
2652 // should probably not consider those cases to be usual deallocation
2653 // functions. But for now we just make an arbitrary choice in that case.
2654 auto Result = resolveDeallocationOverload(*this, FoundDelete, CanProvideSize,
2656 assert(Result.FD && "operator delete missing from global scope?");
2660 FunctionDecl *Sema::FindDeallocationFunctionForDestructor(SourceLocation Loc,
2661 CXXRecordDecl *RD) {
2662 DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Delete);
2664 FunctionDecl *OperatorDelete = nullptr;
2665 if (FindDeallocationFunction(Loc, RD, Name, OperatorDelete))
2668 return OperatorDelete;
2670 // If there's no class-specific operator delete, look up the global
2671 // non-array delete.
2672 return FindUsualDeallocationFunction(
2673 Loc, true, hasNewExtendedAlignment(*this, Context.getRecordType(RD)),
2677 bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
2678 DeclarationName Name,
2679 FunctionDecl *&Operator, bool Diagnose) {
2680 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
2681 // Try to find operator delete/operator delete[] in class scope.
2682 LookupQualifiedName(Found, RD);
2684 if (Found.isAmbiguous())
2687 Found.suppressDiagnostics();
2689 bool Overaligned = hasNewExtendedAlignment(*this, Context.getRecordType(RD));
2691 // C++17 [expr.delete]p10:
2692 // If the deallocation functions have class scope, the one without a
2693 // parameter of type std::size_t is selected.
2694 llvm::SmallVector<UsualDeallocFnInfo, 4> Matches;
2695 resolveDeallocationOverload(*this, Found, /*WantSize*/ false,
2696 /*WantAlign*/ Overaligned, &Matches);
2698 // If we could find an overload, use it.
2699 if (Matches.size() == 1) {
2700 Operator = cast<CXXMethodDecl>(Matches[0].FD);
2702 // FIXME: DiagnoseUseOfDecl?
2703 if (Operator->isDeleted()) {
2705 Diag(StartLoc, diag::err_deleted_function_use);
2706 NoteDeletedFunction(Operator);
2711 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(),
2712 Matches[0].Found, Diagnose) == AR_inaccessible)
2718 // We found multiple suitable operators; complain about the ambiguity.
2719 // FIXME: The standard doesn't say to do this; it appears that the intent
2720 // is that this should never happen.
2721 if (!Matches.empty()) {
2723 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found)
2725 for (auto &Match : Matches)
2726 Diag(Match.FD->getLocation(), diag::note_member_declared_here) << Name;
2731 // We did find operator delete/operator delete[] declarations, but
2732 // none of them were suitable.
2733 if (!Found.empty()) {
2735 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found)
2738 for (NamedDecl *D : Found)
2739 Diag(D->getUnderlyingDecl()->getLocation(),
2740 diag::note_member_declared_here) << Name;
2750 /// \brief Checks whether delete-expression, and new-expression used for
2751 /// initializing deletee have the same array form.
2752 class MismatchingNewDeleteDetector {
2754 enum MismatchResult {
2755 /// Indicates that there is no mismatch or a mismatch cannot be proven.
2757 /// Indicates that variable is initialized with mismatching form of \a new.
2759 /// Indicates that member is initialized with mismatching form of \a new.
2760 MemberInitMismatches,
2761 /// Indicates that 1 or more constructors' definitions could not been
2762 /// analyzed, and they will be checked again at the end of translation unit.
2766 /// \param EndOfTU True, if this is the final analysis at the end of
2767 /// translation unit. False, if this is the initial analysis at the point
2768 /// delete-expression was encountered.
2769 explicit MismatchingNewDeleteDetector(bool EndOfTU)
2770 : Field(nullptr), IsArrayForm(false), EndOfTU(EndOfTU),
2771 HasUndefinedConstructors(false) {}
2773 /// \brief Checks whether pointee of a delete-expression is initialized with
2774 /// matching form of new-expression.
2776 /// If return value is \c VarInitMismatches or \c MemberInitMismatches at the
2777 /// point where delete-expression is encountered, then a warning will be
2778 /// issued immediately. If return value is \c AnalyzeLater at the point where
2779 /// delete-expression is seen, then member will be analyzed at the end of
2780 /// translation unit. \c AnalyzeLater is returned iff at least one constructor
2781 /// couldn't be analyzed. If at least one constructor initializes the member
2782 /// with matching type of new, the return value is \c NoMismatch.
2783 MismatchResult analyzeDeleteExpr(const CXXDeleteExpr *DE);
2784 /// \brief Analyzes a class member.
2785 /// \param Field Class member to analyze.
2786 /// \param DeleteWasArrayForm Array form-ness of the delete-expression used
2787 /// for deleting the \p Field.
2788 MismatchResult analyzeField(FieldDecl *Field, bool DeleteWasArrayForm);
2790 /// List of mismatching new-expressions used for initialization of the pointee
2791 llvm::SmallVector<const CXXNewExpr *, 4> NewExprs;
2792 /// Indicates whether delete-expression was in array form.
2797 /// \brief Indicates that there is at least one constructor without body.
2798 bool HasUndefinedConstructors;
2799 /// \brief Returns \c CXXNewExpr from given initialization expression.
2800 /// \param E Expression used for initializing pointee in delete-expression.
2801 /// E can be a single-element \c InitListExpr consisting of new-expression.
2802 const CXXNewExpr *getNewExprFromInitListOrExpr(const Expr *E);
2803 /// \brief Returns whether member is initialized with mismatching form of
2804 /// \c new either by the member initializer or in-class initialization.
2806 /// If bodies of all constructors are not visible at the end of translation
2807 /// unit or at least one constructor initializes member with the matching
2808 /// form of \c new, mismatch cannot be proven, and this function will return
2810 MismatchResult analyzeMemberExpr(const MemberExpr *ME);
2811 /// \brief Returns whether variable is initialized with mismatching form of
2814 /// If variable is initialized with matching form of \c new or variable is not
2815 /// initialized with a \c new expression, this function will return true.
2816 /// If variable is initialized with mismatching form of \c new, returns false.
2817 /// \param D Variable to analyze.
2818 bool hasMatchingVarInit(const DeclRefExpr *D);
2819 /// \brief Checks whether the constructor initializes pointee with mismatching
2822 /// Returns true, if member is initialized with matching form of \c new in
2823 /// member initializer list. Returns false, if member is initialized with the
2824 /// matching form of \c new in this constructor's initializer or given
2825 /// constructor isn't defined at the point where delete-expression is seen, or
2826 /// member isn't initialized by the constructor.
2827 bool hasMatchingNewInCtor(const CXXConstructorDecl *CD);
2828 /// \brief Checks whether member is initialized with matching form of
2829 /// \c new in member initializer list.
2830 bool hasMatchingNewInCtorInit(const CXXCtorInitializer *CI);
2831 /// Checks whether member is initialized with mismatching form of \c new by
2832 /// in-class initializer.
2833 MismatchResult analyzeInClassInitializer();
2837 MismatchingNewDeleteDetector::MismatchResult
2838 MismatchingNewDeleteDetector::analyzeDeleteExpr(const CXXDeleteExpr *DE) {
2840 assert(DE && "Expected delete-expression");
2841 IsArrayForm = DE->isArrayForm();
2842 const Expr *E = DE->getArgument()->IgnoreParenImpCasts();
2843 if (const MemberExpr *ME = dyn_cast<const MemberExpr>(E)) {
2844 return analyzeMemberExpr(ME);
2845 } else if (const DeclRefExpr *D = dyn_cast<const DeclRefExpr>(E)) {
2846 if (!hasMatchingVarInit(D))
2847 return VarInitMismatches;
2853 MismatchingNewDeleteDetector::getNewExprFromInitListOrExpr(const Expr *E) {
2854 assert(E != nullptr && "Expected a valid initializer expression");
2855 E = E->IgnoreParenImpCasts();
2856 if (const InitListExpr *ILE = dyn_cast<const InitListExpr>(E)) {
2857 if (ILE->getNumInits() == 1)
2858 E = dyn_cast<const CXXNewExpr>(ILE->getInit(0)->IgnoreParenImpCasts());
2861 return dyn_cast_or_null<const CXXNewExpr>(E);
2864 bool MismatchingNewDeleteDetector::hasMatchingNewInCtorInit(
2865 const CXXCtorInitializer *CI) {
2866 const CXXNewExpr *NE = nullptr;
2867 if (Field == CI->getMember() &&
2868 (NE = getNewExprFromInitListOrExpr(CI->getInit()))) {
2869 if (NE->isArray() == IsArrayForm)
2872 NewExprs.push_back(NE);
2877 bool MismatchingNewDeleteDetector::hasMatchingNewInCtor(
2878 const CXXConstructorDecl *CD) {
2879 if (CD->isImplicit())
2881 const FunctionDecl *Definition = CD;
2882 if (!CD->isThisDeclarationADefinition() && !CD->isDefined(Definition)) {
2883 HasUndefinedConstructors = true;
2886 for (const auto *CI : cast<const CXXConstructorDecl>(Definition)->inits()) {
2887 if (hasMatchingNewInCtorInit(CI))
2893 MismatchingNewDeleteDetector::MismatchResult
2894 MismatchingNewDeleteDetector::analyzeInClassInitializer() {
2895 assert(Field != nullptr && "This should be called only for members");
2896 const Expr *InitExpr = Field->getInClassInitializer();
2898 return EndOfTU ? NoMismatch : AnalyzeLater;
2899 if (const CXXNewExpr *NE = getNewExprFromInitListOrExpr(InitExpr)) {
2900 if (NE->isArray() != IsArrayForm) {
2901 NewExprs.push_back(NE);
2902 return MemberInitMismatches;
2908 MismatchingNewDeleteDetector::MismatchResult
2909 MismatchingNewDeleteDetector::analyzeField(FieldDecl *Field,
2910 bool DeleteWasArrayForm) {
2911 assert(Field != nullptr && "Analysis requires a valid class member.");
2912 this->Field = Field;
2913 IsArrayForm = DeleteWasArrayForm;
2914 const CXXRecordDecl *RD = cast<const CXXRecordDecl>(Field->getParent());
2915 for (const auto *CD : RD->ctors()) {
2916 if (hasMatchingNewInCtor(CD))
2919 if (HasUndefinedConstructors)
2920 return EndOfTU ? NoMismatch : AnalyzeLater;
2921 if (!NewExprs.empty())
2922 return MemberInitMismatches;
2923 return Field->hasInClassInitializer() ? analyzeInClassInitializer()
2927 MismatchingNewDeleteDetector::MismatchResult
2928 MismatchingNewDeleteDetector::analyzeMemberExpr(const MemberExpr *ME) {
2929 assert(ME != nullptr && "Expected a member expression");
2930 if (FieldDecl *F = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2931 return analyzeField(F, IsArrayForm);
2935 bool MismatchingNewDeleteDetector::hasMatchingVarInit(const DeclRefExpr *D) {
2936 const CXXNewExpr *NE = nullptr;
2937 if (const VarDecl *VD = dyn_cast<const VarDecl>(D->getDecl())) {
2938 if (VD->hasInit() && (NE = getNewExprFromInitListOrExpr(VD->getInit())) &&
2939 NE->isArray() != IsArrayForm) {
2940 NewExprs.push_back(NE);
2943 return NewExprs.empty();
2947 DiagnoseMismatchedNewDelete(Sema &SemaRef, SourceLocation DeleteLoc,
2948 const MismatchingNewDeleteDetector &Detector) {
2949 SourceLocation EndOfDelete = SemaRef.getLocForEndOfToken(DeleteLoc);
2951 if (!Detector.IsArrayForm)
2952 H = FixItHint::CreateInsertion(EndOfDelete, "[]");
2954 SourceLocation RSquare = Lexer::findLocationAfterToken(
2955 DeleteLoc, tok::l_square, SemaRef.getSourceManager(),
2956 SemaRef.getLangOpts(), true);
2957 if (RSquare.isValid())
2958 H = FixItHint::CreateRemoval(SourceRange(EndOfDelete, RSquare));
2960 SemaRef.Diag(DeleteLoc, diag::warn_mismatched_delete_new)
2961 << Detector.IsArrayForm << H;
2963 for (const auto *NE : Detector.NewExprs)
2964 SemaRef.Diag(NE->getExprLoc(), diag::note_allocated_here)
2965 << Detector.IsArrayForm;
2968 void Sema::AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE) {
2969 if (Diags.isIgnored(diag::warn_mismatched_delete_new, SourceLocation()))
2971 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/false);
2972 switch (Detector.analyzeDeleteExpr(DE)) {
2973 case MismatchingNewDeleteDetector::VarInitMismatches:
2974 case MismatchingNewDeleteDetector::MemberInitMismatches: {
2975 DiagnoseMismatchedNewDelete(*this, DE->getLocStart(), Detector);
2978 case MismatchingNewDeleteDetector::AnalyzeLater: {
2979 DeleteExprs[Detector.Field].push_back(
2980 std::make_pair(DE->getLocStart(), DE->isArrayForm()));
2983 case MismatchingNewDeleteDetector::NoMismatch:
2988 void Sema::AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
2989 bool DeleteWasArrayForm) {
2990 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/true);
2991 switch (Detector.analyzeField(Field, DeleteWasArrayForm)) {
2992 case MismatchingNewDeleteDetector::VarInitMismatches:
2993 llvm_unreachable("This analysis should have been done for class members.");
2994 case MismatchingNewDeleteDetector::AnalyzeLater:
2995 llvm_unreachable("Analysis cannot be postponed any point beyond end of "
2996 "translation unit.");
2997 case MismatchingNewDeleteDetector::MemberInitMismatches:
2998 DiagnoseMismatchedNewDelete(*this, DeleteLoc, Detector);
3000 case MismatchingNewDeleteDetector::NoMismatch:
3005 /// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in:
3006 /// @code ::delete ptr; @endcode
3008 /// @code delete [] ptr; @endcode
3010 Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
3011 bool ArrayForm, Expr *ExE) {
3012 // C++ [expr.delete]p1:
3013 // The operand shall have a pointer type, or a class type having a single
3014 // non-explicit conversion function to a pointer type. The result has type
3017 // DR599 amends "pointer type" to "pointer to object type" in both cases.
3019 ExprResult Ex = ExE;
3020 FunctionDecl *OperatorDelete = nullptr;
3021 bool ArrayFormAsWritten = ArrayForm;
3022 bool UsualArrayDeleteWantsSize = false;
3024 if (!Ex.get()->isTypeDependent()) {
3025 // Perform lvalue-to-rvalue cast, if needed.
3026 Ex = DefaultLvalueConversion(Ex.get());
3030 QualType Type = Ex.get()->getType();
3032 class DeleteConverter : public ContextualImplicitConverter {
3034 DeleteConverter() : ContextualImplicitConverter(false, true) {}
3036 bool match(QualType ConvType) override {
3037 // FIXME: If we have an operator T* and an operator void*, we must pick
3039 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
3040 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType())
3045 SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
3046 QualType T) override {
3047 return S.Diag(Loc, diag::err_delete_operand) << T;
3050 SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
3051 QualType T) override {
3052 return S.Diag(Loc, diag::err_delete_incomplete_class_type) << T;
3055 SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
3057 QualType ConvTy) override {
3058 return S.Diag(Loc, diag::err_delete_explicit_conversion) << T << ConvTy;
3061 SemaDiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
3062 QualType ConvTy) override {
3063 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3067 SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
3068 QualType T) override {
3069 return S.Diag(Loc, diag::err_ambiguous_delete_operand) << T;
3072 SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
3073 QualType ConvTy) override {
3074 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
3078 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
3080 QualType ConvTy) override {
3081 llvm_unreachable("conversion functions are permitted");
3085 Ex = PerformContextualImplicitConversion(StartLoc, Ex.get(), Converter);
3088 Type = Ex.get()->getType();
3089 if (!Converter.match(Type))
3090 // FIXME: PerformContextualImplicitConversion should return ExprError
3091 // itself in this case.
3094 QualType Pointee = Type->getAs<PointerType>()->getPointeeType();
3095 QualType PointeeElem = Context.getBaseElementType(Pointee);
3097 if (unsigned AddressSpace = Pointee.getAddressSpace())
3098 return Diag(Ex.get()->getLocStart(),
3099 diag::err_address_space_qualified_delete)
3100 << Pointee.getUnqualifiedType() << AddressSpace;
3102 CXXRecordDecl *PointeeRD = nullptr;
3103 if (Pointee->isVoidType() && !isSFINAEContext()) {
3104 // The C++ standard bans deleting a pointer to a non-object type, which
3105 // effectively bans deletion of "void*". However, most compilers support
3106 // this, so we treat it as a warning unless we're in a SFINAE context.
3107 Diag(StartLoc, diag::ext_delete_void_ptr_operand)
3108 << Type << Ex.get()->getSourceRange();
3109 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) {
3110 return ExprError(Diag(StartLoc, diag::err_delete_operand)
3111 << Type << Ex.get()->getSourceRange());
3112 } else if (!Pointee->isDependentType()) {
3113 // FIXME: This can result in errors if the definition was imported from a
3114 // module but is hidden.
3115 if (!RequireCompleteType(StartLoc, Pointee,
3116 diag::warn_delete_incomplete, Ex.get())) {
3117 if (const RecordType *RT = PointeeElem->getAs<RecordType>())
3118 PointeeRD = cast<CXXRecordDecl>(RT->getDecl());
3122 if (Pointee->isArrayType() && !ArrayForm) {
3123 Diag(StartLoc, diag::warn_delete_array_type)
3124 << Type << Ex.get()->getSourceRange()
3125 << FixItHint::CreateInsertion(getLocForEndOfToken(StartLoc), "[]");
3129 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
3130 ArrayForm ? OO_Array_Delete : OO_Delete);
3134 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName,
3138 // If we're allocating an array of records, check whether the
3139 // usual operator delete[] has a size_t parameter.
3141 // If the user specifically asked to use the global allocator,
3142 // we'll need to do the lookup into the class.
3144 UsualArrayDeleteWantsSize =
3145 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem);
3147 // Otherwise, the usual operator delete[] should be the
3148 // function we just found.
3149 else if (OperatorDelete && isa<CXXMethodDecl>(OperatorDelete))
3150 UsualArrayDeleteWantsSize =
3151 UsualDeallocFnInfo(*this,
3152 DeclAccessPair::make(OperatorDelete, AS_public))
3156 if (!PointeeRD->hasIrrelevantDestructor())
3157 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3158 MarkFunctionReferenced(StartLoc,
3159 const_cast<CXXDestructorDecl*>(Dtor));
3160 if (DiagnoseUseOfDecl(Dtor, StartLoc))
3164 CheckVirtualDtorCall(PointeeRD->getDestructor(), StartLoc,
3165 /*IsDelete=*/true, /*CallCanBeVirtual=*/true,
3166 /*WarnOnNonAbstractTypes=*/!ArrayForm,
3170 if (!OperatorDelete) {
3171 bool IsComplete = isCompleteType(StartLoc, Pointee);
3172 bool CanProvideSize =
3173 IsComplete && (!ArrayForm || UsualArrayDeleteWantsSize ||
3174 Pointee.isDestructedType());
3175 bool Overaligned = hasNewExtendedAlignment(*this, Pointee);
3177 // Look for a global declaration.
3178 OperatorDelete = FindUsualDeallocationFunction(StartLoc, CanProvideSize,
3179 Overaligned, DeleteName);
3182 MarkFunctionReferenced(StartLoc, OperatorDelete);
3184 // Check access and ambiguity of operator delete and destructor.
3186 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3187 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor,
3188 PDiag(diag::err_access_dtor) << PointeeElem);
3193 CXXDeleteExpr *Result = new (Context) CXXDeleteExpr(
3194 Context.VoidTy, UseGlobal, ArrayForm, ArrayFormAsWritten,
3195 UsualArrayDeleteWantsSize, OperatorDelete, Ex.get(), StartLoc);
3196 AnalyzeDeleteExprMismatch(Result);
3200 void Sema::CheckVirtualDtorCall(CXXDestructorDecl *dtor, SourceLocation Loc,
3201 bool IsDelete, bool CallCanBeVirtual,
3202 bool WarnOnNonAbstractTypes,
3203 SourceLocation DtorLoc) {
3204 if (!dtor || dtor->isVirtual() || !CallCanBeVirtual)
3207 // C++ [expr.delete]p3:
3208 // In the first alternative (delete object), if the static type of the
3209 // object to be deleted is different from its dynamic type, the static
3210 // type shall be a base class of the dynamic type of the object to be
3211 // deleted and the static type shall have a virtual destructor or the
3212 // behavior is undefined.
3214 const CXXRecordDecl *PointeeRD = dtor->getParent();
3215 // Note: a final class cannot be derived from, no issue there
3216 if (!PointeeRD->isPolymorphic() || PointeeRD->hasAttr<FinalAttr>())
3219 QualType ClassType = dtor->getThisType(Context)->getPointeeType();
3220 if (PointeeRD->isAbstract()) {
3221 // If the class is abstract, we warn by default, because we're
3222 // sure the code has undefined behavior.
3223 Diag(Loc, diag::warn_delete_abstract_non_virtual_dtor) << (IsDelete ? 0 : 1)
3225 } else if (WarnOnNonAbstractTypes) {
3226 // Otherwise, if this is not an array delete, it's a bit suspect,
3227 // but not necessarily wrong.
3228 Diag(Loc, diag::warn_delete_non_virtual_dtor) << (IsDelete ? 0 : 1)
3232 std::string TypeStr;
3233 ClassType.getAsStringInternal(TypeStr, getPrintingPolicy());
3234 Diag(DtorLoc, diag::note_delete_non_virtual)
3235 << FixItHint::CreateInsertion(DtorLoc, TypeStr + "::");
3239 Sema::ConditionResult Sema::ActOnConditionVariable(Decl *ConditionVar,
3240 SourceLocation StmtLoc,
3243 CheckConditionVariable(cast<VarDecl>(ConditionVar), StmtLoc, CK);
3245 return ConditionError();
3246 return ConditionResult(*this, ConditionVar, MakeFullExpr(E.get(), StmtLoc),
3247 CK == ConditionKind::ConstexprIf);
3250 /// \brief Check the use of the given variable as a C++ condition in an if,
3251 /// while, do-while, or switch statement.
3252 ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar,
3253 SourceLocation StmtLoc,
3255 if (ConditionVar->isInvalidDecl())
3258 QualType T = ConditionVar->getType();
3260 // C++ [stmt.select]p2:
3261 // The declarator shall not specify a function or an array.
3262 if (T->isFunctionType())
3263 return ExprError(Diag(ConditionVar->getLocation(),
3264 diag::err_invalid_use_of_function_type)
3265 << ConditionVar->getSourceRange());
3266 else if (T->isArrayType())
3267 return ExprError(Diag(ConditionVar->getLocation(),
3268 diag::err_invalid_use_of_array_type)
3269 << ConditionVar->getSourceRange());
3271 ExprResult Condition = DeclRefExpr::Create(
3272 Context, NestedNameSpecifierLoc(), SourceLocation(), ConditionVar,
3273 /*enclosing*/ false, ConditionVar->getLocation(),
3274 ConditionVar->getType().getNonReferenceType(), VK_LValue);
3276 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get()));
3279 case ConditionKind::Boolean:
3280 return CheckBooleanCondition(StmtLoc, Condition.get());
3282 case ConditionKind::ConstexprIf:
3283 return CheckBooleanCondition(StmtLoc, Condition.get(), true);
3285 case ConditionKind::Switch:
3286 return CheckSwitchCondition(StmtLoc, Condition.get());
3289 llvm_unreachable("unexpected condition kind");
3292 /// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
3293 ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr, bool IsConstexpr) {
3295 // The value of a condition that is an initialized declaration in a statement
3296 // other than a switch statement is the value of the declared variable
3297 // implicitly converted to type bool. If that conversion is ill-formed, the
3298 // program is ill-formed.
3299 // The value of a condition that is an expression is the value of the
3300 // expression, implicitly converted to bool.
3302 // FIXME: Return this value to the caller so they don't need to recompute it.
3303 llvm::APSInt Value(/*BitWidth*/1);
3304 return (IsConstexpr && !CondExpr->isValueDependent())
3305 ? CheckConvertedConstantExpression(CondExpr, Context.BoolTy, Value,
3307 : PerformContextuallyConvertToBool(CondExpr);
3310 /// Helper function to determine whether this is the (deprecated) C++
3311 /// conversion from a string literal to a pointer to non-const char or
3312 /// non-const wchar_t (for narrow and wide string literals,
3315 Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) {
3316 // Look inside the implicit cast, if it exists.
3317 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From))
3318 From = Cast->getSubExpr();
3320 // A string literal (2.13.4) that is not a wide string literal can
3321 // be converted to an rvalue of type "pointer to char"; a wide
3322 // string literal can be converted to an rvalue of type "pointer
3323 // to wchar_t" (C++ 4.2p2).
3324 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens()))
3325 if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
3326 if (const BuiltinType *ToPointeeType
3327 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
3328 // This conversion is considered only when there is an
3329 // explicit appropriate pointer target type (C++ 4.2p2).
3330 if (!ToPtrType->getPointeeType().hasQualifiers()) {
3331 switch (StrLit->getKind()) {
3332 case StringLiteral::UTF8:
3333 case StringLiteral::UTF16:
3334 case StringLiteral::UTF32:
3335 // We don't allow UTF literals to be implicitly converted
3337 case StringLiteral::Ascii:
3338 return (ToPointeeType->getKind() == BuiltinType::Char_U ||
3339 ToPointeeType->getKind() == BuiltinType::Char_S);
3340 case StringLiteral::Wide:
3341 return Context.typesAreCompatible(Context.getWideCharType(),
3342 QualType(ToPointeeType, 0));
3350 static ExprResult BuildCXXCastArgument(Sema &S,
3351 SourceLocation CastLoc,
3354 CXXMethodDecl *Method,
3355 DeclAccessPair FoundDecl,
3356 bool HadMultipleCandidates,
3359 default: llvm_unreachable("Unhandled cast kind!");
3360 case CK_ConstructorConversion: {
3361 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method);
3362 SmallVector<Expr*, 8> ConstructorArgs;
3364 if (S.RequireNonAbstractType(CastLoc, Ty,
3365 diag::err_allocation_of_abstract_type))
3368 if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs))
3371 S.CheckConstructorAccess(CastLoc, Constructor, FoundDecl,
3372 InitializedEntity::InitializeTemporary(Ty));
3373 if (S.DiagnoseUseOfDecl(Method, CastLoc))
3376 ExprResult Result = S.BuildCXXConstructExpr(
3377 CastLoc, Ty, FoundDecl, cast<CXXConstructorDecl>(Method),
3378 ConstructorArgs, HadMultipleCandidates,
3379 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3380 CXXConstructExpr::CK_Complete, SourceRange());
3381 if (Result.isInvalid())
3384 return S.MaybeBindToTemporary(Result.getAs<Expr>());
3387 case CK_UserDefinedConversion: {
3388 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
3390 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ nullptr, FoundDecl);
3391 if (S.DiagnoseUseOfDecl(Method, CastLoc))
3394 // Create an implicit call expr that calls it.
3395 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method);
3396 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv,
3397 HadMultipleCandidates);
3398 if (Result.isInvalid())
3400 // Record usage of conversion in an implicit cast.
3401 Result = ImplicitCastExpr::Create(S.Context, Result.get()->getType(),
3402 CK_UserDefinedConversion, Result.get(),
3403 nullptr, Result.get()->getValueKind());
3405 return S.MaybeBindToTemporary(Result.get());
3410 /// PerformImplicitConversion - Perform an implicit conversion of the
3411 /// expression From to the type ToType using the pre-computed implicit
3412 /// conversion sequence ICS. Returns the converted
3413 /// expression. Action is the kind of conversion we're performing,
3414 /// used in the error message.
3416 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
3417 const ImplicitConversionSequence &ICS,
3418 AssignmentAction Action,
3419 CheckedConversionKind CCK) {
3420 switch (ICS.getKind()) {
3421 case ImplicitConversionSequence::StandardConversion: {
3422 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard,
3424 if (Res.isInvalid())
3430 case ImplicitConversionSequence::UserDefinedConversion: {
3432 FunctionDecl *FD = ICS.UserDefined.ConversionFunction;
3434 QualType BeforeToType;
3435 assert(FD && "no conversion function for user-defined conversion seq");
3436 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) {
3437 CastKind = CK_UserDefinedConversion;
3439 // If the user-defined conversion is specified by a conversion function,
3440 // the initial standard conversion sequence converts the source type to
3441 // the implicit object parameter of the conversion function.
3442 BeforeToType = Context.getTagDeclType(Conv->getParent());
3444 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD);
3445 CastKind = CK_ConstructorConversion;
3446 // Do no conversion if dealing with ... for the first conversion.
3447 if (!ICS.UserDefined.EllipsisConversion) {
3448 // If the user-defined conversion is specified by a constructor, the
3449 // initial standard conversion sequence converts the source type to
3450 // the type required by the argument of the constructor
3451 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType();
3454 // Watch out for ellipsis conversion.
3455 if (!ICS.UserDefined.EllipsisConversion) {
3457 PerformImplicitConversion(From, BeforeToType,
3458 ICS.UserDefined.Before, AA_Converting,
3460 if (Res.isInvalid())
3466 = BuildCXXCastArgument(*this,
3467 From->getLocStart(),
3468 ToType.getNonReferenceType(),
3469 CastKind, cast<CXXMethodDecl>(FD),
3470 ICS.UserDefined.FoundConversionFunction,
3471 ICS.UserDefined.HadMultipleCandidates,
3474 if (CastArg.isInvalid())
3477 From = CastArg.get();
3479 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
3480 AA_Converting, CCK);
3483 case ImplicitConversionSequence::AmbiguousConversion:
3484 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(),
3485 PDiag(diag::err_typecheck_ambiguous_condition)
3486 << From->getSourceRange());
3489 case ImplicitConversionSequence::EllipsisConversion:
3490 llvm_unreachable("Cannot perform an ellipsis conversion");
3492 case ImplicitConversionSequence::BadConversion:
3494 DiagnoseAssignmentResult(Incompatible, From->getExprLoc(), ToType,
3495 From->getType(), From, Action);
3496 assert(Diagnosed && "failed to diagnose bad conversion"); (void)Diagnosed;
3500 // Everything went well.
3504 /// PerformImplicitConversion - Perform an implicit conversion of the
3505 /// expression From to the type ToType by following the standard
3506 /// conversion sequence SCS. Returns the converted
3507 /// expression. Flavor is the context in which we're performing this
3508 /// conversion, for use in error messages.
3510 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
3511 const StandardConversionSequence& SCS,
3512 AssignmentAction Action,
3513 CheckedConversionKind CCK) {
3514 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast);
3516 // Overall FIXME: we are recomputing too many types here and doing far too
3517 // much extra work. What this means is that we need to keep track of more
3518 // information that is computed when we try the implicit conversion initially,
3519 // so that we don't need to recompute anything here.
3520 QualType FromType = From->getType();
3522 if (SCS.CopyConstructor) {
3523 // FIXME: When can ToType be a reference type?
3524 assert(!ToType->isReferenceType());
3525 if (SCS.Second == ICK_Derived_To_Base) {
3526 SmallVector<Expr*, 8> ConstructorArgs;
3527 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor),
3528 From, /*FIXME:ConstructLoc*/SourceLocation(),
3531 return BuildCXXConstructExpr(
3532 /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
3533 SCS.FoundCopyConstructor, SCS.CopyConstructor,
3534 ConstructorArgs, /*HadMultipleCandidates*/ false,
3535 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3536 CXXConstructExpr::CK_Complete, SourceRange());
3538 return BuildCXXConstructExpr(
3539 /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
3540 SCS.FoundCopyConstructor, SCS.CopyConstructor,
3541 From, /*HadMultipleCandidates*/ false,
3542 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3543 CXXConstructExpr::CK_Complete, SourceRange());
3546 // Resolve overloaded function references.
3547 if (Context.hasSameType(FromType, Context.OverloadTy)) {
3548 DeclAccessPair Found;
3549 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType,
3554 if (DiagnoseUseOfDecl(Fn, From->getLocStart()))
3557 From = FixOverloadedFunctionReference(From, Found, Fn);
3558 FromType = From->getType();
3561 // If we're converting to an atomic type, first convert to the corresponding
3563 QualType ToAtomicType;
3564 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) {
3565 ToAtomicType = ToType;
3566 ToType = ToAtomic->getValueType();
3569 QualType InitialFromType = FromType;
3570 // Perform the first implicit conversion.
3571 switch (SCS.First) {
3573 if (const AtomicType *FromAtomic = FromType->getAs<AtomicType>()) {
3574 FromType = FromAtomic->getValueType().getUnqualifiedType();
3575 From = ImplicitCastExpr::Create(Context, FromType, CK_AtomicToNonAtomic,
3576 From, /*BasePath=*/nullptr, VK_RValue);
3580 case ICK_Lvalue_To_Rvalue: {
3581 assert(From->getObjectKind() != OK_ObjCProperty);
3582 ExprResult FromRes = DefaultLvalueConversion(From);
3583 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!");
3584 From = FromRes.get();
3585 FromType = From->getType();
3589 case ICK_Array_To_Pointer:
3590 FromType = Context.getArrayDecayedType(FromType);
3591 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay,
3592 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3595 case ICK_Function_To_Pointer:
3596 FromType = Context.getPointerType(FromType);
3597 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay,
3598 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3602 llvm_unreachable("Improper first standard conversion");
3605 // Perform the second implicit conversion
3606 switch (SCS.Second) {
3608 // C++ [except.spec]p5:
3609 // [For] assignment to and initialization of pointers to functions,
3610 // pointers to member functions, and references to functions: the
3611 // target entity shall allow at least the exceptions allowed by the
3612 // source value in the assignment or initialization.
3615 case AA_Initializing:
3616 // Note, function argument passing and returning are initialization.
3620 case AA_Passing_CFAudited:
3621 if (CheckExceptionSpecCompatibility(From, ToType))
3627 // Casts and implicit conversions are not initialization, so are not
3628 // checked for exception specification mismatches.
3631 // Nothing else to do.
3634 case ICK_Integral_Promotion:
3635 case ICK_Integral_Conversion:
3636 if (ToType->isBooleanType()) {
3637 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() &&
3638 SCS.Second == ICK_Integral_Promotion &&
3639 "only enums with fixed underlying type can promote to bool");
3640 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean,
3641 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3643 From = ImpCastExprToType(From, ToType, CK_IntegralCast,
3644 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3648 case ICK_Floating_Promotion:
3649 case ICK_Floating_Conversion:
3650 From = ImpCastExprToType(From, ToType, CK_FloatingCast,
3651 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3654 case ICK_Complex_Promotion:
3655 case ICK_Complex_Conversion: {
3656 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType();
3657 QualType ToEl = ToType->getAs<ComplexType>()->getElementType();
3659 if (FromEl->isRealFloatingType()) {
3660 if (ToEl->isRealFloatingType())
3661 CK = CK_FloatingComplexCast;
3663 CK = CK_FloatingComplexToIntegralComplex;
3664 } else if (ToEl->isRealFloatingType()) {
3665 CK = CK_IntegralComplexToFloatingComplex;
3667 CK = CK_IntegralComplexCast;
3669 From = ImpCastExprToType(From, ToType, CK,
3670 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3674 case ICK_Floating_Integral:
3675 if (ToType->isRealFloatingType())
3676 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating,
3677 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3679 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral,
3680 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3683 case ICK_Compatible_Conversion:
3684 From = ImpCastExprToType(From, ToType, CK_NoOp,
3685 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3688 case ICK_Writeback_Conversion:
3689 case ICK_Pointer_Conversion: {
3690 if (SCS.IncompatibleObjC && Action != AA_Casting) {
3691 // Diagnose incompatible Objective-C conversions
3692 if (Action == AA_Initializing || Action == AA_Assigning)
3693 Diag(From->getLocStart(),
3694 diag::ext_typecheck_convert_incompatible_pointer)
3695 << ToType << From->getType() << Action
3696 << From->getSourceRange() << 0;
3698 Diag(From->getLocStart(),
3699 diag::ext_typecheck_convert_incompatible_pointer)
3700 << From->getType() << ToType << Action
3701 << From->getSourceRange() << 0;
3703 if (From->getType()->isObjCObjectPointerType() &&
3704 ToType->isObjCObjectPointerType())
3705 EmitRelatedResultTypeNote(From);
3707 else if (getLangOpts().ObjCAutoRefCount &&
3708 !CheckObjCARCUnavailableWeakConversion(ToType,
3710 if (Action == AA_Initializing)
3711 Diag(From->getLocStart(),
3712 diag::err_arc_weak_unavailable_assign);
3714 Diag(From->getLocStart(),
3715 diag::err_arc_convesion_of_weak_unavailable)
3716 << (Action == AA_Casting) << From->getType() << ToType
3717 << From->getSourceRange();
3720 CastKind Kind = CK_Invalid;
3721 CXXCastPath BasePath;
3722 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle))
3725 // Make sure we extend blocks if necessary.
3726 // FIXME: doing this here is really ugly.
3727 if (Kind == CK_BlockPointerToObjCPointerCast) {
3728 ExprResult E = From;
3729 (void) PrepareCastToObjCObjectPointer(E);
3732 if (getLangOpts().ObjCAutoRefCount)
3733 CheckObjCARCConversion(SourceRange(), ToType, From, CCK);
3734 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
3739 case ICK_Pointer_Member: {
3740 CastKind Kind = CK_Invalid;
3741 CXXCastPath BasePath;
3742 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle))
3744 if (CheckExceptionSpecCompatibility(From, ToType))
3747 // We may not have been able to figure out what this member pointer resolved
3748 // to up until this exact point. Attempt to lock-in it's inheritance model.
3749 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
3750 (void)isCompleteType(From->getExprLoc(), From->getType());
3751 (void)isCompleteType(From->getExprLoc(), ToType);
3754 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
3759 case ICK_Boolean_Conversion:
3760 // Perform half-to-boolean conversion via float.
3761 if (From->getType()->isHalfType()) {
3762 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).get();
3763 FromType = Context.FloatTy;
3766 From = ImpCastExprToType(From, Context.BoolTy,
3767 ScalarTypeToBooleanCastKind(FromType),
3768 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3771 case ICK_Derived_To_Base: {
3772 CXXCastPath BasePath;
3773 if (CheckDerivedToBaseConversion(From->getType(),
3774 ToType.getNonReferenceType(),
3775 From->getLocStart(),
3776 From->getSourceRange(),
3781 From = ImpCastExprToType(From, ToType.getNonReferenceType(),
3782 CK_DerivedToBase, From->getValueKind(),
3783 &BasePath, CCK).get();
3787 case ICK_Vector_Conversion:
3788 From = ImpCastExprToType(From, ToType, CK_BitCast,
3789 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3792 case ICK_Vector_Splat: {
3793 // Vector splat from any arithmetic type to a vector.
3794 Expr *Elem = prepareVectorSplat(ToType, From).get();
3795 From = ImpCastExprToType(Elem, ToType, CK_VectorSplat, VK_RValue,
3796 /*BasePath=*/nullptr, CCK).get();
3800 case ICK_Complex_Real:
3801 // Case 1. x -> _Complex y
3802 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) {
3803 QualType ElType = ToComplex->getElementType();
3804 bool isFloatingComplex = ElType->isRealFloatingType();
3807 if (Context.hasSameUnqualifiedType(ElType, From->getType())) {
3809 } else if (From->getType()->isRealFloatingType()) {
3810 From = ImpCastExprToType(From, ElType,
3811 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).get();
3813 assert(From->getType()->isIntegerType());
3814 From = ImpCastExprToType(From, ElType,
3815 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).get();
3818 From = ImpCastExprToType(From, ToType,
3819 isFloatingComplex ? CK_FloatingRealToComplex
3820 : CK_IntegralRealToComplex).get();
3822 // Case 2. _Complex x -> y
3824 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>();
3825 assert(FromComplex);
3827 QualType ElType = FromComplex->getElementType();
3828 bool isFloatingComplex = ElType->isRealFloatingType();
3831 From = ImpCastExprToType(From, ElType,
3832 isFloatingComplex ? CK_FloatingComplexToReal
3833 : CK_IntegralComplexToReal,
3834 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3837 if (Context.hasSameUnqualifiedType(ElType, ToType)) {
3839 } else if (ToType->isRealFloatingType()) {
3840 From = ImpCastExprToType(From, ToType,
3841 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating,
3842 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3844 assert(ToType->isIntegerType());
3845 From = ImpCastExprToType(From, ToType,
3846 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast,
3847 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3852 case ICK_Block_Pointer_Conversion: {
3853 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast,
3854 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3858 case ICK_TransparentUnionConversion: {
3859 ExprResult FromRes = From;
3860 Sema::AssignConvertType ConvTy =
3861 CheckTransparentUnionArgumentConstraints(ToType, FromRes);
3862 if (FromRes.isInvalid())
3864 From = FromRes.get();
3865 assert ((ConvTy == Sema::Compatible) &&
3866 "Improper transparent union conversion");
3871 case ICK_Zero_Event_Conversion:
3872 From = ImpCastExprToType(From, ToType,
3874 From->getValueKind()).get();
3877 case ICK_Zero_Queue_Conversion:
3878 From = ImpCastExprToType(From, ToType,
3880 From->getValueKind()).get();
3883 case ICK_Lvalue_To_Rvalue:
3884 case ICK_Array_To_Pointer:
3885 case ICK_Function_To_Pointer:
3886 case ICK_Function_Conversion:
3887 case ICK_Qualification:
3888 case ICK_Num_Conversion_Kinds:
3889 case ICK_C_Only_Conversion:
3890 case ICK_Incompatible_Pointer_Conversion:
3891 llvm_unreachable("Improper second standard conversion");
3894 switch (SCS.Third) {
3899 case ICK_Function_Conversion:
3900 // If both sides are functions (or pointers/references to them), there could
3901 // be incompatible exception declarations.
3902 if (CheckExceptionSpecCompatibility(From, ToType))
3905 From = ImpCastExprToType(From, ToType, CK_NoOp,
3906 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3909 case ICK_Qualification: {
3910 // The qualification keeps the category of the inner expression, unless the
3911 // target type isn't a reference.
3912 ExprValueKind VK = ToType->isReferenceType() ?
3913 From->getValueKind() : VK_RValue;
3914 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context),
3915 CK_NoOp, VK, /*BasePath=*/nullptr, CCK).get();
3917 if (SCS.DeprecatedStringLiteralToCharPtr &&
3918 !getLangOpts().WritableStrings) {
3919 Diag(From->getLocStart(), getLangOpts().CPlusPlus11
3920 ? diag::ext_deprecated_string_literal_conversion
3921 : diag::warn_deprecated_string_literal_conversion)
3922 << ToType.getNonReferenceType();
3929 llvm_unreachable("Improper third standard conversion");
3932 // If this conversion sequence involved a scalar -> atomic conversion, perform
3933 // that conversion now.
3934 if (!ToAtomicType.isNull()) {
3935 assert(Context.hasSameType(
3936 ToAtomicType->castAs<AtomicType>()->getValueType(), From->getType()));
3937 From = ImpCastExprToType(From, ToAtomicType, CK_NonAtomicToAtomic,
3938 VK_RValue, nullptr, CCK).get();
3941 // If this conversion sequence succeeded and involved implicitly converting a
3942 // _Nullable type to a _Nonnull one, complain.
3943 if (CCK == CCK_ImplicitConversion)
3944 diagnoseNullableToNonnullConversion(ToType, InitialFromType,
3945 From->getLocStart());
3950 /// \brief Check the completeness of a type in a unary type trait.
3952 /// If the particular type trait requires a complete type, tries to complete
3953 /// it. If completing the type fails, a diagnostic is emitted and false
3954 /// returned. If completing the type succeeds or no completion was required,
3956 static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, TypeTrait UTT,
3959 // C++0x [meta.unary.prop]p3:
3960 // For all of the class templates X declared in this Clause, instantiating
3961 // that template with a template argument that is a class template
3962 // specialization may result in the implicit instantiation of the template
3963 // argument if and only if the semantics of X require that the argument
3964 // must be a complete type.
3965 // We apply this rule to all the type trait expressions used to implement
3966 // these class templates. We also try to follow any GCC documented behavior
3967 // in these expressions to ensure portability of standard libraries.
3969 default: llvm_unreachable("not a UTT");
3970 // is_complete_type somewhat obviously cannot require a complete type.
3971 case UTT_IsCompleteType:
3974 // These traits are modeled on the type predicates in C++0x
3975 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as
3976 // requiring a complete type, as whether or not they return true cannot be
3977 // impacted by the completeness of the type.
3979 case UTT_IsIntegral:
3980 case UTT_IsFloatingPoint:
3983 case UTT_IsLvalueReference:
3984 case UTT_IsRvalueReference:
3985 case UTT_IsMemberFunctionPointer:
3986 case UTT_IsMemberObjectPointer:
3990 case UTT_IsFunction:
3991 case UTT_IsReference:
3992 case UTT_IsArithmetic:
3993 case UTT_IsFundamental:
3996 case UTT_IsCompound:
3997 case UTT_IsMemberPointer:
4000 // These traits are modeled on type predicates in C++0x [meta.unary.prop]
4001 // which requires some of its traits to have the complete type. However,
4002 // the completeness of the type cannot impact these traits' semantics, and
4003 // so they don't require it. This matches the comments on these traits in
4006 case UTT_IsVolatile:
4008 case UTT_IsUnsigned:
4010 // This type trait always returns false, checking the type is moot.
4011 case UTT_IsInterfaceClass:
4014 // C++14 [meta.unary.prop]:
4015 // If T is a non-union class type, T shall be a complete type.
4017 case UTT_IsPolymorphic:
4018 case UTT_IsAbstract:
4019 if (const auto *RD = ArgTy->getAsCXXRecordDecl())
4021 return !S.RequireCompleteType(
4022 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4025 // C++14 [meta.unary.prop]:
4026 // If T is a class type, T shall be a complete type.
4029 if (ArgTy->getAsCXXRecordDecl())
4030 return !S.RequireCompleteType(
4031 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
4034 // C++0x [meta.unary.prop] Table 49 requires the following traits to be
4035 // applied to a complete type.
4037 case UTT_IsTriviallyCopyable:
4038 case UTT_IsStandardLayout:
4042 case UTT_IsDestructible:
4043 case UTT_IsNothrowDestructible:
4046 // These trait expressions are designed to help implement predicates in
4047 // [meta.unary.prop] despite not being named the same. They are specified
4048 // by both GCC and the Embarcadero C++ compiler, and require the complete
4049 // type due to the overarching C++0x type predicates being implemented
4050 // requiring the complete type.
4051 case UTT_HasNothrowAssign:
4052 case UTT_HasNothrowMoveAssign:
4053 case UTT_HasNothrowConstructor:
4054 case UTT_HasNothrowCopy:
4055 case UTT_HasTrivialAssign:
4056 case UTT_HasTrivialMoveAssign:
4057 case UTT_HasTrivialDefaultConstructor:
4058 case UTT_HasTrivialMoveConstructor:
4059 case UTT_HasTrivialCopy:
4060 case UTT_HasTrivialDestructor:
4061 case UTT_HasVirtualDestructor:
4062 // Arrays of unknown bound are expressly allowed.
4063 QualType ElTy = ArgTy;
4064 if (ArgTy->isIncompleteArrayType())
4065 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType();
4067 // The void type is expressly allowed.
4068 if (ElTy->isVoidType())
4071 return !S.RequireCompleteType(
4072 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr);
4076 static bool HasNoThrowOperator(const RecordType *RT, OverloadedOperatorKind Op,
4077 Sema &Self, SourceLocation KeyLoc, ASTContext &C,
4078 bool (CXXRecordDecl::*HasTrivial)() const,
4079 bool (CXXRecordDecl::*HasNonTrivial)() const,
4080 bool (CXXMethodDecl::*IsDesiredOp)() const)
4082 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
4083 if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)())
4086 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op);
4087 DeclarationNameInfo NameInfo(Name, KeyLoc);
4088 LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName);
4089 if (Self.LookupQualifiedName(Res, RD)) {
4090 bool FoundOperator = false;
4091 Res.suppressDiagnostics();
4092 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end();
4093 Op != OpEnd; ++Op) {
4094 if (isa<FunctionTemplateDecl>(*Op))
4097 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op);
4098 if((Operator->*IsDesiredOp)()) {
4099 FoundOperator = true;
4100 const FunctionProtoType *CPT =
4101 Operator->getType()->getAs<FunctionProtoType>();
4102 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4103 if (!CPT || !CPT->isNothrow(C))
4107 return FoundOperator;
4112 static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
4113 SourceLocation KeyLoc, QualType T) {
4114 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
4116 ASTContext &C = Self.Context;
4118 default: llvm_unreachable("not a UTT");
4119 // Type trait expressions corresponding to the primary type category
4120 // predicates in C++0x [meta.unary.cat].
4122 return T->isVoidType();
4123 case UTT_IsIntegral:
4124 return T->isIntegralType(C);
4125 case UTT_IsFloatingPoint:
4126 return T->isFloatingType();
4128 return T->isArrayType();
4130 return T->isPointerType();
4131 case UTT_IsLvalueReference:
4132 return T->isLValueReferenceType();
4133 case UTT_IsRvalueReference:
4134 return T->isRValueReferenceType();
4135 case UTT_IsMemberFunctionPointer:
4136 return T->isMemberFunctionPointerType();
4137 case UTT_IsMemberObjectPointer:
4138 return T->isMemberDataPointerType();
4140 return T->isEnumeralType();
4142 return T->isUnionType();
4144 return T->isClassType() || T->isStructureType() || T->isInterfaceType();
4145 case UTT_IsFunction:
4146 return T->isFunctionType();
4148 // Type trait expressions which correspond to the convenient composition
4149 // predicates in C++0x [meta.unary.comp].
4150 case UTT_IsReference:
4151 return T->isReferenceType();
4152 case UTT_IsArithmetic:
4153 return T->isArithmeticType() && !T->isEnumeralType();
4154 case UTT_IsFundamental:
4155 return T->isFundamentalType();
4157 return T->isObjectType();
4159 // Note: semantic analysis depends on Objective-C lifetime types to be
4160 // considered scalar types. However, such types do not actually behave
4161 // like scalar types at run time (since they may require retain/release
4162 // operations), so we report them as non-scalar.
4163 if (T->isObjCLifetimeType()) {
4164 switch (T.getObjCLifetime()) {
4165 case Qualifiers::OCL_None:
4166 case Qualifiers::OCL_ExplicitNone:
4169 case Qualifiers::OCL_Strong:
4170 case Qualifiers::OCL_Weak:
4171 case Qualifiers::OCL_Autoreleasing:
4176 return T->isScalarType();
4177 case UTT_IsCompound:
4178 return T->isCompoundType();
4179 case UTT_IsMemberPointer:
4180 return T->isMemberPointerType();
4182 // Type trait expressions which correspond to the type property predicates
4183 // in C++0x [meta.unary.prop].
4185 return T.isConstQualified();
4186 case UTT_IsVolatile:
4187 return T.isVolatileQualified();
4189 return T.isTrivialType(C);
4190 case UTT_IsTriviallyCopyable:
4191 return T.isTriviallyCopyableType(C);
4192 case UTT_IsStandardLayout:
4193 return T->isStandardLayoutType();
4195 return T.isPODType(C);
4197 return T->isLiteralType(C);
4199 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4200 return !RD->isUnion() && RD->isEmpty();
4202 case UTT_IsPolymorphic:
4203 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4204 return !RD->isUnion() && RD->isPolymorphic();
4206 case UTT_IsAbstract:
4207 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4208 return !RD->isUnion() && RD->isAbstract();
4210 // __is_interface_class only returns true when CL is invoked in /CLR mode and
4211 // even then only when it is used with the 'interface struct ...' syntax
4212 // Clang doesn't support /CLR which makes this type trait moot.
4213 case UTT_IsInterfaceClass:
4217 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4218 return RD->hasAttr<FinalAttr>();
4221 return T->isSignedIntegerType();
4222 case UTT_IsUnsigned:
4223 return T->isUnsignedIntegerType();
4225 // Type trait expressions which query classes regarding their construction,
4226 // destruction, and copying. Rather than being based directly on the
4227 // related type predicates in the standard, they are specified by both
4228 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those
4231 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
4232 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4234 // Note that these builtins do not behave as documented in g++: if a class
4235 // has both a trivial and a non-trivial special member of a particular kind,
4236 // they return false! For now, we emulate this behavior.
4237 // FIXME: This appears to be a g++ bug: more complex cases reveal that it
4238 // does not correctly compute triviality in the presence of multiple special
4239 // members of the same kind. Revisit this once the g++ bug is fixed.
4240 case UTT_HasTrivialDefaultConstructor:
4241 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4242 // If __is_pod (type) is true then the trait is true, else if type is
4243 // a cv class or union type (or array thereof) with a trivial default
4244 // constructor ([class.ctor]) then the trait is true, else it is false.
4247 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4248 return RD->hasTrivialDefaultConstructor() &&
4249 !RD->hasNonTrivialDefaultConstructor();
4251 case UTT_HasTrivialMoveConstructor:
4252 // This trait is implemented by MSVC 2012 and needed to parse the
4253 // standard library headers. Specifically this is used as the logic
4254 // behind std::is_trivially_move_constructible (20.9.4.3).
4257 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4258 return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor();
4260 case UTT_HasTrivialCopy:
4261 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4262 // If __is_pod (type) is true or type is a reference type then
4263 // the trait is true, else if type is a cv class or union type
4264 // with a trivial copy constructor ([class.copy]) then the trait
4265 // is true, else it is false.
4266 if (T.isPODType(C) || T->isReferenceType())
4268 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4269 return RD->hasTrivialCopyConstructor() &&
4270 !RD->hasNonTrivialCopyConstructor();
4272 case UTT_HasTrivialMoveAssign:
4273 // This trait is implemented by MSVC 2012 and needed to parse the
4274 // standard library headers. Specifically it is used as the logic
4275 // behind std::is_trivially_move_assignable (20.9.4.3)
4278 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4279 return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment();
4281 case UTT_HasTrivialAssign:
4282 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4283 // If type is const qualified or is a reference type then the
4284 // trait is false. Otherwise if __is_pod (type) is true then the
4285 // trait is true, else if type is a cv class or union type with
4286 // a trivial copy assignment ([class.copy]) then the trait is
4287 // true, else it is false.
4288 // Note: the const and reference restrictions are interesting,
4289 // given that const and reference members don't prevent a class
4290 // from having a trivial copy assignment operator (but do cause
4291 // errors if the copy assignment operator is actually used, q.v.
4292 // [class.copy]p12).
4294 if (T.isConstQualified())
4298 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4299 return RD->hasTrivialCopyAssignment() &&
4300 !RD->hasNonTrivialCopyAssignment();
4302 case UTT_IsDestructible:
4303 case UTT_IsNothrowDestructible:
4304 // C++14 [meta.unary.prop]:
4305 // For reference types, is_destructible<T>::value is true.
4306 if (T->isReferenceType())
4309 // Objective-C++ ARC: autorelease types don't require destruction.
4310 if (T->isObjCLifetimeType() &&
4311 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
4314 // C++14 [meta.unary.prop]:
4315 // For incomplete types and function types, is_destructible<T>::value is
4317 if (T->isIncompleteType() || T->isFunctionType())
4320 // C++14 [meta.unary.prop]:
4321 // For object types and given U equal to remove_all_extents_t<T>, if the
4322 // expression std::declval<U&>().~U() is well-formed when treated as an
4323 // unevaluated operand (Clause 5), then is_destructible<T>::value is true
4324 if (auto *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
4325 CXXDestructorDecl *Destructor = Self.LookupDestructor(RD);
4328 // C++14 [dcl.fct.def.delete]p2:
4329 // A program that refers to a deleted function implicitly or
4330 // explicitly, other than to declare it, is ill-formed.
4331 if (Destructor->isDeleted())
4333 if (C.getLangOpts().AccessControl && Destructor->getAccess() != AS_public)
4335 if (UTT == UTT_IsNothrowDestructible) {
4336 const FunctionProtoType *CPT =
4337 Destructor->getType()->getAs<FunctionProtoType>();
4338 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4339 if (!CPT || !CPT->isNothrow(C))
4345 case UTT_HasTrivialDestructor:
4346 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
4347 // If __is_pod (type) is true or type is a reference type
4348 // then the trait is true, else if type is a cv class or union
4349 // type (or array thereof) with a trivial destructor
4350 // ([class.dtor]) then the trait is true, else it is
4352 if (T.isPODType(C) || T->isReferenceType())
4355 // Objective-C++ ARC: autorelease types don't require destruction.
4356 if (T->isObjCLifetimeType() &&
4357 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
4360 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4361 return RD->hasTrivialDestructor();
4363 // TODO: Propagate nothrowness for implicitly declared special members.
4364 case UTT_HasNothrowAssign:
4365 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4366 // If type is const qualified or is a reference type then the
4367 // trait is false. Otherwise if __has_trivial_assign (type)
4368 // is true then the trait is true, else if type is a cv class
4369 // or union type with copy assignment operators that are known
4370 // not to throw an exception then the trait is true, else it is
4372 if (C.getBaseElementType(T).isConstQualified())
4374 if (T->isReferenceType())
4376 if (T.isPODType(C) || T->isObjCLifetimeType())
4379 if (const RecordType *RT = T->getAs<RecordType>())
4380 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
4381 &CXXRecordDecl::hasTrivialCopyAssignment,
4382 &CXXRecordDecl::hasNonTrivialCopyAssignment,
4383 &CXXMethodDecl::isCopyAssignmentOperator);
4385 case UTT_HasNothrowMoveAssign:
4386 // This trait is implemented by MSVC 2012 and needed to parse the
4387 // standard library headers. Specifically this is used as the logic
4388 // behind std::is_nothrow_move_assignable (20.9.4.3).
4392 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>())
4393 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
4394 &CXXRecordDecl::hasTrivialMoveAssignment,
4395 &CXXRecordDecl::hasNonTrivialMoveAssignment,
4396 &CXXMethodDecl::isMoveAssignmentOperator);
4398 case UTT_HasNothrowCopy:
4399 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4400 // If __has_trivial_copy (type) is true then the trait is true, else
4401 // if type is a cv class or union type with copy constructors that are
4402 // known not to throw an exception then the trait is true, else it is
4404 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
4406 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
4407 if (RD->hasTrivialCopyConstructor() &&
4408 !RD->hasNonTrivialCopyConstructor())
4411 bool FoundConstructor = false;
4413 for (const auto *ND : Self.LookupConstructors(RD)) {
4414 // A template constructor is never a copy constructor.
4415 // FIXME: However, it may actually be selected at the actual overload
4416 // resolution point.
4417 if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
4419 // UsingDecl itself is not a constructor
4420 if (isa<UsingDecl>(ND))
4422 auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
4423 if (Constructor->isCopyConstructor(FoundTQs)) {
4424 FoundConstructor = true;
4425 const FunctionProtoType *CPT
4426 = Constructor->getType()->getAs<FunctionProtoType>();
4427 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4430 // TODO: check whether evaluating default arguments can throw.
4431 // For now, we'll be conservative and assume that they can throw.
4432 if (!CPT->isNothrow(C) || CPT->getNumParams() > 1)
4437 return FoundConstructor;
4440 case UTT_HasNothrowConstructor:
4441 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
4442 // If __has_trivial_constructor (type) is true then the trait is
4443 // true, else if type is a cv class or union type (or array
4444 // thereof) with a default constructor that is known not to
4445 // throw an exception then the trait is true, else it is false.
4446 if (T.isPODType(C) || T->isObjCLifetimeType())
4448 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
4449 if (RD->hasTrivialDefaultConstructor() &&
4450 !RD->hasNonTrivialDefaultConstructor())
4453 bool FoundConstructor = false;
4454 for (const auto *ND : Self.LookupConstructors(RD)) {
4455 // FIXME: In C++0x, a constructor template can be a default constructor.
4456 if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
4458 // UsingDecl itself is not a constructor
4459 if (isa<UsingDecl>(ND))
4461 auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
4462 if (Constructor->isDefaultConstructor()) {
4463 FoundConstructor = true;
4464 const FunctionProtoType *CPT
4465 = Constructor->getType()->getAs<FunctionProtoType>();
4466 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4469 // FIXME: check whether evaluating default arguments can throw.
4470 // For now, we'll be conservative and assume that they can throw.
4471 if (!CPT->isNothrow(C) || CPT->getNumParams() > 0)
4475 return FoundConstructor;
4478 case UTT_HasVirtualDestructor:
4479 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4480 // If type is a class type with a virtual destructor ([class.dtor])
4481 // then the trait is true, else it is false.
4482 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4483 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
4484 return Destructor->isVirtual();
4487 // These type trait expressions are modeled on the specifications for the
4488 // Embarcadero C++0x type trait functions:
4489 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4490 case UTT_IsCompleteType:
4491 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_):
4492 // Returns True if and only if T is a complete type at the point of the
4494 return !T->isIncompleteType();
4498 /// \brief Determine whether T has a non-trivial Objective-C lifetime in
4500 static bool hasNontrivialObjCLifetime(QualType T) {
4501 switch (T.getObjCLifetime()) {
4502 case Qualifiers::OCL_ExplicitNone:
4505 case Qualifiers::OCL_Strong:
4506 case Qualifiers::OCL_Weak:
4507 case Qualifiers::OCL_Autoreleasing:
4510 case Qualifiers::OCL_None:
4511 return T->isObjCLifetimeType();
4514 llvm_unreachable("Unknown ObjC lifetime qualifier");
4517 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
4518 QualType RhsT, SourceLocation KeyLoc);
4520 static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc,
4521 ArrayRef<TypeSourceInfo *> Args,
4522 SourceLocation RParenLoc) {
4523 if (Kind <= UTT_Last)
4524 return EvaluateUnaryTypeTrait(S, Kind, KWLoc, Args[0]->getType());
4526 if (Kind <= BTT_Last)
4527 return EvaluateBinaryTypeTrait(S, Kind, Args[0]->getType(),
4528 Args[1]->getType(), RParenLoc);
4531 case clang::TT_IsConstructible:
4532 case clang::TT_IsNothrowConstructible:
4533 case clang::TT_IsTriviallyConstructible: {
4534 // C++11 [meta.unary.prop]:
4535 // is_trivially_constructible is defined as:
4537 // is_constructible<T, Args...>::value is true and the variable
4538 // definition for is_constructible, as defined below, is known to call
4539 // no operation that is not trivial.
4541 // The predicate condition for a template specialization
4542 // is_constructible<T, Args...> shall be satisfied if and only if the
4543 // following variable definition would be well-formed for some invented
4546 // T t(create<Args>()...);
4547 assert(!Args.empty());
4549 // Precondition: T and all types in the parameter pack Args shall be
4550 // complete types, (possibly cv-qualified) void, or arrays of
4552 for (const auto *TSI : Args) {
4553 QualType ArgTy = TSI->getType();
4554 if (ArgTy->isVoidType() || ArgTy->isIncompleteArrayType())
4557 if (S.RequireCompleteType(KWLoc, ArgTy,
4558 diag::err_incomplete_type_used_in_type_trait_expr))
4562 // Make sure the first argument is not incomplete nor a function type.
4563 QualType T = Args[0]->getType();
4564 if (T->isIncompleteType() || T->isFunctionType())
4567 // Make sure the first argument is not an abstract type.
4568 CXXRecordDecl *RD = T->getAsCXXRecordDecl();
4569 if (RD && RD->isAbstract())
4572 SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs;
4573 SmallVector<Expr *, 2> ArgExprs;
4574 ArgExprs.reserve(Args.size() - 1);
4575 for (unsigned I = 1, N = Args.size(); I != N; ++I) {
4576 QualType ArgTy = Args[I]->getType();
4577 if (ArgTy->isObjectType() || ArgTy->isFunctionType())
4578 ArgTy = S.Context.getRValueReferenceType(ArgTy);
4579 OpaqueArgExprs.push_back(
4580 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(),
4581 ArgTy.getNonLValueExprType(S.Context),
4582 Expr::getValueKindForType(ArgTy)));
4584 for (Expr &E : OpaqueArgExprs)
4585 ArgExprs.push_back(&E);
4587 // Perform the initialization in an unevaluated context within a SFINAE
4588 // trap at translation unit scope.
4589 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated);
4590 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
4591 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl());
4592 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0]));
4593 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc,
4595 InitializationSequence Init(S, To, InitKind, ArgExprs);
4599 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs);
4600 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
4603 if (Kind == clang::TT_IsConstructible)
4606 if (Kind == clang::TT_IsNothrowConstructible)
4607 return S.canThrow(Result.get()) == CT_Cannot;
4609 if (Kind == clang::TT_IsTriviallyConstructible) {
4610 // Under Objective-C ARC, if the destination has non-trivial Objective-C
4611 // lifetime, this is a non-trivial construction.
4612 if (S.getLangOpts().ObjCAutoRefCount &&
4613 hasNontrivialObjCLifetime(T.getNonReferenceType()))
4616 // The initialization succeeded; now make sure there are no non-trivial
4618 return !Result.get()->hasNonTrivialCall(S.Context);
4621 llvm_unreachable("unhandled type trait");
4624 default: llvm_unreachable("not a TT");
4630 ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4631 ArrayRef<TypeSourceInfo *> Args,
4632 SourceLocation RParenLoc) {
4633 QualType ResultType = Context.getLogicalOperationType();
4635 if (Kind <= UTT_Last && !CheckUnaryTypeTraitTypeCompleteness(
4636 *this, Kind, KWLoc, Args[0]->getType()))
4639 bool Dependent = false;
4640 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
4641 if (Args[I]->getType()->isDependentType()) {
4647 bool Result = false;
4649 Result = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc);
4651 return TypeTraitExpr::Create(Context, ResultType, KWLoc, Kind, Args,
4655 ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4656 ArrayRef<ParsedType> Args,
4657 SourceLocation RParenLoc) {
4658 SmallVector<TypeSourceInfo *, 4> ConvertedArgs;
4659 ConvertedArgs.reserve(Args.size());
4661 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
4662 TypeSourceInfo *TInfo;
4663 QualType T = GetTypeFromParser(Args[I], &TInfo);
4665 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc);
4667 ConvertedArgs.push_back(TInfo);
4670 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc);
4673 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
4674 QualType RhsT, SourceLocation KeyLoc) {
4675 assert(!LhsT->isDependentType() && !RhsT->isDependentType() &&
4676 "Cannot evaluate traits of dependent types");
4679 case BTT_IsBaseOf: {
4680 // C++0x [meta.rel]p2
4681 // Base is a base class of Derived without regard to cv-qualifiers or
4682 // Base and Derived are not unions and name the same class type without
4683 // regard to cv-qualifiers.
4685 const RecordType *lhsRecord = LhsT->getAs<RecordType>();
4686 if (!lhsRecord) return false;
4688 const RecordType *rhsRecord = RhsT->getAs<RecordType>();
4689 if (!rhsRecord) return false;
4691 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT)
4692 == (lhsRecord == rhsRecord));
4694 if (lhsRecord == rhsRecord)
4695 return !lhsRecord->getDecl()->isUnion();
4697 // C++0x [meta.rel]p2:
4698 // If Base and Derived are class types and are different types
4699 // (ignoring possible cv-qualifiers) then Derived shall be a
4701 if (Self.RequireCompleteType(KeyLoc, RhsT,
4702 diag::err_incomplete_type_used_in_type_trait_expr))
4705 return cast<CXXRecordDecl>(rhsRecord->getDecl())
4706 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl()));
4709 return Self.Context.hasSameType(LhsT, RhsT);
4710 case BTT_TypeCompatible:
4711 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(),
4712 RhsT.getUnqualifiedType());
4713 case BTT_IsConvertible:
4714 case BTT_IsConvertibleTo: {
4715 // C++0x [meta.rel]p4:
4716 // Given the following function prototype:
4718 // template <class T>
4719 // typename add_rvalue_reference<T>::type create();
4721 // the predicate condition for a template specialization
4722 // is_convertible<From, To> shall be satisfied if and only if
4723 // the return expression in the following code would be
4724 // well-formed, including any implicit conversions to the return
4725 // type of the function:
4728 // return create<From>();
4731 // Access checking is performed as if in a context unrelated to To and
4732 // From. Only the validity of the immediate context of the expression
4733 // of the return-statement (including conversions to the return type)
4736 // We model the initialization as a copy-initialization of a temporary
4737 // of the appropriate type, which for this expression is identical to the
4738 // return statement (since NRVO doesn't apply).
4740 // Functions aren't allowed to return function or array types.
4741 if (RhsT->isFunctionType() || RhsT->isArrayType())
4744 // A return statement in a void function must have void type.
4745 if (RhsT->isVoidType())
4746 return LhsT->isVoidType();
4748 // A function definition requires a complete, non-abstract return type.
4749 if (!Self.isCompleteType(KeyLoc, RhsT) || Self.isAbstractType(KeyLoc, RhsT))
4752 // Compute the result of add_rvalue_reference.
4753 if (LhsT->isObjectType() || LhsT->isFunctionType())
4754 LhsT = Self.Context.getRValueReferenceType(LhsT);
4756 // Build a fake source and destination for initialization.
4757 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT));
4758 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
4759 Expr::getValueKindForType(LhsT));
4760 Expr *FromPtr = &From;
4761 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc,
4764 // Perform the initialization in an unevaluated context within a SFINAE
4765 // trap at translation unit scope.
4766 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated);
4767 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
4768 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
4769 InitializationSequence Init(Self, To, Kind, FromPtr);
4773 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr);
4774 return !Result.isInvalid() && !SFINAE.hasErrorOccurred();
4777 case BTT_IsAssignable:
4778 case BTT_IsNothrowAssignable:
4779 case BTT_IsTriviallyAssignable: {
4780 // C++11 [meta.unary.prop]p3:
4781 // is_trivially_assignable is defined as:
4782 // is_assignable<T, U>::value is true and the assignment, as defined by
4783 // is_assignable, is known to call no operation that is not trivial
4785 // is_assignable is defined as:
4786 // The expression declval<T>() = declval<U>() is well-formed when
4787 // treated as an unevaluated operand (Clause 5).
4789 // For both, T and U shall be complete types, (possibly cv-qualified)
4790 // void, or arrays of unknown bound.
4791 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() &&
4792 Self.RequireCompleteType(KeyLoc, LhsT,
4793 diag::err_incomplete_type_used_in_type_trait_expr))
4795 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() &&
4796 Self.RequireCompleteType(KeyLoc, RhsT,
4797 diag::err_incomplete_type_used_in_type_trait_expr))
4800 // cv void is never assignable.
4801 if (LhsT->isVoidType() || RhsT->isVoidType())
4804 // Build expressions that emulate the effect of declval<T>() and
4806 if (LhsT->isObjectType() || LhsT->isFunctionType())
4807 LhsT = Self.Context.getRValueReferenceType(LhsT);
4808 if (RhsT->isObjectType() || RhsT->isFunctionType())
4809 RhsT = Self.Context.getRValueReferenceType(RhsT);
4810 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
4811 Expr::getValueKindForType(LhsT));
4812 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context),
4813 Expr::getValueKindForType(RhsT));
4815 // Attempt the assignment in an unevaluated context within a SFINAE
4816 // trap at translation unit scope.
4817 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated);
4818 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
4819 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
4820 ExprResult Result = Self.BuildBinOp(/*S=*/nullptr, KeyLoc, BO_Assign, &Lhs,
4822 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
4825 if (BTT == BTT_IsAssignable)
4828 if (BTT == BTT_IsNothrowAssignable)
4829 return Self.canThrow(Result.get()) == CT_Cannot;
4831 if (BTT == BTT_IsTriviallyAssignable) {
4832 // Under Objective-C ARC, if the destination has non-trivial Objective-C
4833 // lifetime, this is a non-trivial assignment.
4834 if (Self.getLangOpts().ObjCAutoRefCount &&
4835 hasNontrivialObjCLifetime(LhsT.getNonReferenceType()))
4838 return !Result.get()->hasNonTrivialCall(Self.Context);
4841 llvm_unreachable("unhandled type trait");
4844 default: llvm_unreachable("not a BTT");
4846 llvm_unreachable("Unknown type trait or not implemented");
4849 ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT,
4850 SourceLocation KWLoc,
4853 SourceLocation RParen) {
4854 TypeSourceInfo *TSInfo;
4855 QualType T = GetTypeFromParser(Ty, &TSInfo);
4857 TSInfo = Context.getTrivialTypeSourceInfo(T);
4859 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen);
4862 static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT,
4863 QualType T, Expr *DimExpr,
4864 SourceLocation KeyLoc) {
4865 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
4869 if (T->isArrayType()) {
4871 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
4873 T = AT->getElementType();
4879 case ATT_ArrayExtent: {
4882 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value,
4883 diag::err_dimension_expr_not_constant_integer,
4886 if (Value.isSigned() && Value.isNegative()) {
4887 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer)
4888 << DimExpr->getSourceRange();
4891 Dim = Value.getLimitedValue();
4893 if (T->isArrayType()) {
4895 bool Matched = false;
4896 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
4902 T = AT->getElementType();
4905 if (Matched && T->isArrayType()) {
4906 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T))
4907 return CAT->getSize().getLimitedValue();
4913 llvm_unreachable("Unknown type trait or not implemented");
4916 ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT,
4917 SourceLocation KWLoc,
4918 TypeSourceInfo *TSInfo,
4920 SourceLocation RParen) {
4921 QualType T = TSInfo->getType();
4923 // FIXME: This should likely be tracked as an APInt to remove any host
4924 // assumptions about the width of size_t on the target.
4926 if (!T->isDependentType())
4927 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc);
4929 // While the specification for these traits from the Embarcadero C++
4930 // compiler's documentation says the return type is 'unsigned int', Clang
4931 // returns 'size_t'. On Windows, the primary platform for the Embarcadero
4932 // compiler, there is no difference. On several other platforms this is an
4933 // important distinction.
4934 return new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, DimExpr,
4935 RParen, Context.getSizeType());
4938 ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET,
4939 SourceLocation KWLoc,
4941 SourceLocation RParen) {
4942 // If error parsing the expression, ignore.
4946 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen);
4951 static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) {
4953 case ET_IsLValueExpr: return E->isLValue();
4954 case ET_IsRValueExpr: return E->isRValue();
4956 llvm_unreachable("Expression trait not covered by switch");
4959 ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET,
4960 SourceLocation KWLoc,
4962 SourceLocation RParen) {
4963 if (Queried->isTypeDependent()) {
4964 // Delay type-checking for type-dependent expressions.
4965 } else if (Queried->getType()->isPlaceholderType()) {
4966 ExprResult PE = CheckPlaceholderExpr(Queried);
4967 if (PE.isInvalid()) return ExprError();
4968 return BuildExpressionTrait(ET, KWLoc, PE.get(), RParen);
4971 bool Value = EvaluateExpressionTrait(ET, Queried);
4973 return new (Context)
4974 ExpressionTraitExpr(KWLoc, ET, Queried, Value, RParen, Context.BoolTy);
4977 QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS,
4981 assert(!LHS.get()->getType()->isPlaceholderType() &&
4982 !RHS.get()->getType()->isPlaceholderType() &&
4983 "placeholders should have been weeded out by now");
4985 // The LHS undergoes lvalue conversions if this is ->*, and undergoes the
4986 // temporary materialization conversion otherwise.
4988 LHS = DefaultLvalueConversion(LHS.get());
4989 else if (LHS.get()->isRValue())
4990 LHS = TemporaryMaterializationConversion(LHS.get());
4991 if (LHS.isInvalid())
4994 // The RHS always undergoes lvalue conversions.
4995 RHS = DefaultLvalueConversion(RHS.get());
4996 if (RHS.isInvalid()) return QualType();
4998 const char *OpSpelling = isIndirect ? "->*" : ".*";
5000 // The binary operator .* [p3: ->*] binds its second operand, which shall
5001 // be of type "pointer to member of T" (where T is a completely-defined
5002 // class type) [...]
5003 QualType RHSType = RHS.get()->getType();
5004 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>();
5006 Diag(Loc, diag::err_bad_memptr_rhs)
5007 << OpSpelling << RHSType << RHS.get()->getSourceRange();
5011 QualType Class(MemPtr->getClass(), 0);
5013 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the
5014 // member pointer points must be completely-defined. However, there is no
5015 // reason for this semantic distinction, and the rule is not enforced by
5016 // other compilers. Therefore, we do not check this property, as it is
5017 // likely to be considered a defect.
5020 // [...] to its first operand, which shall be of class T or of a class of
5021 // which T is an unambiguous and accessible base class. [p3: a pointer to
5023 QualType LHSType = LHS.get()->getType();
5025 if (const PointerType *Ptr = LHSType->getAs<PointerType>())
5026 LHSType = Ptr->getPointeeType();
5028 Diag(Loc, diag::err_bad_memptr_lhs)
5029 << OpSpelling << 1 << LHSType
5030 << FixItHint::CreateReplacement(SourceRange(Loc), ".*");
5035 if (!Context.hasSameUnqualifiedType(Class, LHSType)) {
5036 // If we want to check the hierarchy, we need a complete type.
5037 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs,
5038 OpSpelling, (int)isIndirect)) {
5042 if (!IsDerivedFrom(Loc, LHSType, Class)) {
5043 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling
5044 << (int)isIndirect << LHS.get()->getType();
5048 CXXCastPath BasePath;
5049 if (CheckDerivedToBaseConversion(LHSType, Class, Loc,
5050 SourceRange(LHS.get()->getLocStart(),
5051 RHS.get()->getLocEnd()),
5055 // Cast LHS to type of use.
5056 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class;
5057 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind();
5058 LHS = ImpCastExprToType(LHS.get(), UseType, CK_DerivedToBase, VK,
5062 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) {
5063 // Diagnose use of pointer-to-member type which when used as
5064 // the functional cast in a pointer-to-member expression.
5065 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect;
5070 // The result is an object or a function of the type specified by the
5072 // The cv qualifiers are the union of those in the pointer and the left side,
5073 // in accordance with 5.5p5 and 5.2.5.
5074 QualType Result = MemPtr->getPointeeType();
5075 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers());
5077 // C++0x [expr.mptr.oper]p6:
5078 // In a .* expression whose object expression is an rvalue, the program is
5079 // ill-formed if the second operand is a pointer to member function with
5080 // ref-qualifier &. In a ->* expression or in a .* expression whose object
5081 // expression is an lvalue, the program is ill-formed if the second operand
5082 // is a pointer to member function with ref-qualifier &&.
5083 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) {
5084 switch (Proto->getRefQualifier()) {
5090 if (!isIndirect && !LHS.get()->Classify(Context).isLValue())
5091 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
5092 << RHSType << 1 << LHS.get()->getSourceRange();
5096 if (isIndirect || !LHS.get()->Classify(Context).isRValue())
5097 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
5098 << RHSType << 0 << LHS.get()->getSourceRange();
5103 // C++ [expr.mptr.oper]p6:
5104 // The result of a .* expression whose second operand is a pointer
5105 // to a data member is of the same value category as its
5106 // first operand. The result of a .* expression whose second
5107 // operand is a pointer to a member function is a prvalue. The
5108 // result of an ->* expression is an lvalue if its second operand
5109 // is a pointer to data member and a prvalue otherwise.
5110 if (Result->isFunctionType()) {
5112 return Context.BoundMemberTy;
5113 } else if (isIndirect) {
5116 VK = LHS.get()->getValueKind();
5122 /// \brief Try to convert a type to another according to C++11 5.16p3.
5124 /// This is part of the parameter validation for the ? operator. If either
5125 /// value operand is a class type, the two operands are attempted to be
5126 /// converted to each other. This function does the conversion in one direction.
5127 /// It returns true if the program is ill-formed and has already been diagnosed
5129 static bool TryClassUnification(Sema &Self, Expr *From, Expr *To,
5130 SourceLocation QuestionLoc,
5131 bool &HaveConversion,
5133 HaveConversion = false;
5134 ToType = To->getType();
5136 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(),
5139 // The process for determining whether an operand expression E1 of type T1
5140 // can be converted to match an operand expression E2 of type T2 is defined
5142 // -- If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
5143 // implicitly converted to type "lvalue reference to T2", subject to the
5144 // constraint that in the conversion the reference must bind directly to
5146 // -- If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
5147 // implicitly conveted to the type "rvalue reference to R2", subject to
5148 // the constraint that the reference must bind directly.
5149 if (To->isLValue() || To->isXValue()) {
5150 QualType T = To->isLValue() ? Self.Context.getLValueReferenceType(ToType)
5151 : Self.Context.getRValueReferenceType(ToType);
5153 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
5155 InitializationSequence InitSeq(Self, Entity, Kind, From);
5156 if (InitSeq.isDirectReferenceBinding()) {
5158 HaveConversion = true;
5162 if (InitSeq.isAmbiguous())
5163 return InitSeq.Diagnose(Self, Entity, Kind, From);
5166 // -- If E2 is an rvalue, or if the conversion above cannot be done:
5167 // -- if E1 and E2 have class type, and the underlying class types are
5168 // the same or one is a base class of the other:
5169 QualType FTy = From->getType();
5170 QualType TTy = To->getType();
5171 const RecordType *FRec = FTy->getAs<RecordType>();
5172 const RecordType *TRec = TTy->getAs<RecordType>();
5173 bool FDerivedFromT = FRec && TRec && FRec != TRec &&
5174 Self.IsDerivedFrom(QuestionLoc, FTy, TTy);
5175 if (FRec && TRec && (FRec == TRec || FDerivedFromT ||
5176 Self.IsDerivedFrom(QuestionLoc, TTy, FTy))) {
5177 // E1 can be converted to match E2 if the class of T2 is the
5178 // same type as, or a base class of, the class of T1, and
5180 if (FRec == TRec || FDerivedFromT) {
5181 if (TTy.isAtLeastAsQualifiedAs(FTy)) {
5182 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
5183 InitializationSequence InitSeq(Self, Entity, Kind, From);
5185 HaveConversion = true;
5189 if (InitSeq.isAmbiguous())
5190 return InitSeq.Diagnose(Self, Entity, Kind, From);
5197 // -- Otherwise: E1 can be converted to match E2 if E1 can be
5198 // implicitly converted to the type that expression E2 would have
5199 // if E2 were converted to an rvalue (or the type it has, if E2 is
5202 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not
5203 // to the array-to-pointer or function-to-pointer conversions.
5204 TTy = TTy.getNonLValueExprType(Self.Context);
5206 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
5207 InitializationSequence InitSeq(Self, Entity, Kind, From);
5208 HaveConversion = !InitSeq.Failed();
5210 if (InitSeq.isAmbiguous())
5211 return InitSeq.Diagnose(Self, Entity, Kind, From);
5216 /// \brief Try to find a common type for two according to C++0x 5.16p5.
5218 /// This is part of the parameter validation for the ? operator. If either
5219 /// value operand is a class type, overload resolution is used to find a
5220 /// conversion to a common type.
5221 static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS,
5222 SourceLocation QuestionLoc) {
5223 Expr *Args[2] = { LHS.get(), RHS.get() };
5224 OverloadCandidateSet CandidateSet(QuestionLoc,
5225 OverloadCandidateSet::CSK_Operator);
5226 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args,
5229 OverloadCandidateSet::iterator Best;
5230 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) {
5232 // We found a match. Perform the conversions on the arguments and move on.
5234 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0],
5235 Best->Conversions[0], Sema::AA_Converting);
5236 if (LHSRes.isInvalid())
5241 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1],
5242 Best->Conversions[1], Sema::AA_Converting);
5243 if (RHSRes.isInvalid())
5247 Self.MarkFunctionReferenced(QuestionLoc, Best->Function);
5251 case OR_No_Viable_Function:
5253 // Emit a better diagnostic if one of the expressions is a null pointer
5254 // constant and the other is a pointer type. In this case, the user most
5255 // likely forgot to take the address of the other expression.
5256 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
5259 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
5260 << LHS.get()->getType() << RHS.get()->getType()
5261 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5265 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl)
5266 << LHS.get()->getType() << RHS.get()->getType()
5267 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5268 // FIXME: Print the possible common types by printing the return types of
5269 // the viable candidates.
5273 llvm_unreachable("Conditional operator has only built-in overloads");
5278 /// \brief Perform an "extended" implicit conversion as returned by
5279 /// TryClassUnification.
5280 static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) {
5281 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
5282 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(),
5284 Expr *Arg = E.get();
5285 InitializationSequence InitSeq(Self, Entity, Kind, Arg);
5286 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, Arg);
5287 if (Result.isInvalid())
5294 /// \brief Check the operands of ?: under C++ semantics.
5296 /// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y
5297 /// extension. In this case, LHS == Cond. (But they're not aliases.)
5298 QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
5299 ExprResult &RHS, ExprValueKind &VK,
5301 SourceLocation QuestionLoc) {
5302 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++
5303 // interface pointers.
5305 // C++11 [expr.cond]p1
5306 // The first expression is contextually converted to bool.
5307 if (!Cond.get()->isTypeDependent()) {
5308 ExprResult CondRes = CheckCXXBooleanCondition(Cond.get());
5309 if (CondRes.isInvalid())
5318 // Either of the arguments dependent?
5319 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent())
5320 return Context.DependentTy;
5322 // C++11 [expr.cond]p2
5323 // If either the second or the third operand has type (cv) void, ...
5324 QualType LTy = LHS.get()->getType();
5325 QualType RTy = RHS.get()->getType();
5326 bool LVoid = LTy->isVoidType();
5327 bool RVoid = RTy->isVoidType();
5328 if (LVoid || RVoid) {
5329 // ... one of the following shall hold:
5330 // -- The second or the third operand (but not both) is a (possibly
5331 // parenthesized) throw-expression; the result is of the type
5332 // and value category of the other.
5333 bool LThrow = isa<CXXThrowExpr>(LHS.get()->IgnoreParenImpCasts());
5334 bool RThrow = isa<CXXThrowExpr>(RHS.get()->IgnoreParenImpCasts());
5335 if (LThrow != RThrow) {
5336 Expr *NonThrow = LThrow ? RHS.get() : LHS.get();
5337 VK = NonThrow->getValueKind();
5338 // DR (no number yet): the result is a bit-field if the
5339 // non-throw-expression operand is a bit-field.
5340 OK = NonThrow->getObjectKind();
5341 return NonThrow->getType();
5344 // -- Both the second and third operands have type void; the result is of
5345 // type void and is a prvalue.
5347 return Context.VoidTy;
5349 // Neither holds, error.
5350 Diag(QuestionLoc, diag::err_conditional_void_nonvoid)
5351 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1)
5352 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5358 // C++11 [expr.cond]p3
5359 // Otherwise, if the second and third operand have different types, and
5360 // either has (cv) class type [...] an attempt is made to convert each of
5361 // those operands to the type of the other.
5362 if (!Context.hasSameType(LTy, RTy) &&
5363 (LTy->isRecordType() || RTy->isRecordType())) {
5364 // These return true if a single direction is already ambiguous.
5365 QualType L2RType, R2LType;
5366 bool HaveL2R, HaveR2L;
5367 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType))
5369 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType))
5372 // If both can be converted, [...] the program is ill-formed.
5373 if (HaveL2R && HaveR2L) {
5374 Diag(QuestionLoc, diag::err_conditional_ambiguous)
5375 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5379 // If exactly one conversion is possible, that conversion is applied to
5380 // the chosen operand and the converted operands are used in place of the
5381 // original operands for the remainder of this section.
5383 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid())
5385 LTy = LHS.get()->getType();
5386 } else if (HaveR2L) {
5387 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid())
5389 RTy = RHS.get()->getType();
5393 // C++11 [expr.cond]p3
5394 // if both are glvalues of the same value category and the same type except
5395 // for cv-qualification, an attempt is made to convert each of those
5396 // operands to the type of the other.
5398 // Resolving a defect in P0012R1: we extend this to cover all cases where
5399 // one of the operands is reference-compatible with the other, in order
5400 // to support conditionals between functions differing in noexcept.
5401 ExprValueKind LVK = LHS.get()->getValueKind();
5402 ExprValueKind RVK = RHS.get()->getValueKind();
5403 if (!Context.hasSameType(LTy, RTy) &&
5404 LVK == RVK && LVK != VK_RValue) {
5405 // DerivedToBase was already handled by the class-specific case above.
5406 // FIXME: Should we allow ObjC conversions here?
5407 bool DerivedToBase, ObjCConversion, ObjCLifetimeConversion;
5408 if (CompareReferenceRelationship(
5409 QuestionLoc, LTy, RTy, DerivedToBase,
5410 ObjCConversion, ObjCLifetimeConversion) == Ref_Compatible &&
5411 !DerivedToBase && !ObjCConversion && !ObjCLifetimeConversion &&
5412 // [...] subject to the constraint that the reference must bind
5414 !RHS.get()->refersToBitField() &&
5415 !RHS.get()->refersToVectorElement()) {
5416 RHS = ImpCastExprToType(RHS.get(), LTy, CK_NoOp, RVK);
5417 RTy = RHS.get()->getType();
5418 } else if (CompareReferenceRelationship(
5419 QuestionLoc, RTy, LTy, DerivedToBase,
5420 ObjCConversion, ObjCLifetimeConversion) == Ref_Compatible &&
5421 !DerivedToBase && !ObjCConversion && !ObjCLifetimeConversion &&
5422 !LHS.get()->refersToBitField() &&
5423 !LHS.get()->refersToVectorElement()) {
5424 LHS = ImpCastExprToType(LHS.get(), RTy, CK_NoOp, LVK);
5425 LTy = LHS.get()->getType();
5429 // C++11 [expr.cond]p4
5430 // If the second and third operands are glvalues of the same value
5431 // category and have the same type, the result is of that type and
5432 // value category and it is a bit-field if the second or the third
5433 // operand is a bit-field, or if both are bit-fields.
5434 // We only extend this to bitfields, not to the crazy other kinds of
5436 bool Same = Context.hasSameType(LTy, RTy);
5437 if (Same && LVK == RVK && LVK != VK_RValue &&
5438 LHS.get()->isOrdinaryOrBitFieldObject() &&
5439 RHS.get()->isOrdinaryOrBitFieldObject()) {
5440 VK = LHS.get()->getValueKind();
5441 if (LHS.get()->getObjectKind() == OK_BitField ||
5442 RHS.get()->getObjectKind() == OK_BitField)
5445 // If we have function pointer types, unify them anyway to unify their
5446 // exception specifications, if any.
5447 if (LTy->isFunctionPointerType() || LTy->isMemberFunctionPointerType()) {
5448 Qualifiers Qs = LTy.getQualifiers();
5449 LTy = FindCompositePointerType(QuestionLoc, LHS, RHS,
5450 /*ConvertArgs*/false);
5451 LTy = Context.getQualifiedType(LTy, Qs);
5453 assert(!LTy.isNull() && "failed to find composite pointer type for "
5454 "canonically equivalent function ptr types");
5455 assert(Context.hasSameType(LTy, RTy) && "bad composite pointer type");
5461 // C++11 [expr.cond]p5
5462 // Otherwise, the result is a prvalue. If the second and third operands
5463 // do not have the same type, and either has (cv) class type, ...
5464 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) {
5465 // ... overload resolution is used to determine the conversions (if any)
5466 // to be applied to the operands. If the overload resolution fails, the
5467 // program is ill-formed.
5468 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc))
5472 // C++11 [expr.cond]p6
5473 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard
5474 // conversions are performed on the second and third operands.
5475 LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
5476 RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
5477 if (LHS.isInvalid() || RHS.isInvalid())
5479 LTy = LHS.get()->getType();
5480 RTy = RHS.get()->getType();
5482 // After those conversions, one of the following shall hold:
5483 // -- The second and third operands have the same type; the result
5484 // is of that type. If the operands have class type, the result
5485 // is a prvalue temporary of the result type, which is
5486 // copy-initialized from either the second operand or the third
5487 // operand depending on the value of the first operand.
5488 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) {
5489 if (LTy->isRecordType()) {
5490 // The operands have class type. Make a temporary copy.
5491 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy);
5493 ExprResult LHSCopy = PerformCopyInitialization(Entity,
5496 if (LHSCopy.isInvalid())
5499 ExprResult RHSCopy = PerformCopyInitialization(Entity,
5502 if (RHSCopy.isInvalid())
5509 // If we have function pointer types, unify them anyway to unify their
5510 // exception specifications, if any.
5511 if (LTy->isFunctionPointerType() || LTy->isMemberFunctionPointerType()) {
5512 LTy = FindCompositePointerType(QuestionLoc, LHS, RHS);
5513 assert(!LTy.isNull() && "failed to find composite pointer type for "
5514 "canonically equivalent function ptr types");
5520 // Extension: conditional operator involving vector types.
5521 if (LTy->isVectorType() || RTy->isVectorType())
5522 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false,
5523 /*AllowBothBool*/true,
5524 /*AllowBoolConversions*/false);
5526 // -- The second and third operands have arithmetic or enumeration type;
5527 // the usual arithmetic conversions are performed to bring them to a
5528 // common type, and the result is of that type.
5529 if (LTy->isArithmeticType() && RTy->isArithmeticType()) {
5530 QualType ResTy = UsualArithmeticConversions(LHS, RHS);
5531 if (LHS.isInvalid() || RHS.isInvalid())
5533 if (ResTy.isNull()) {
5535 diag::err_typecheck_cond_incompatible_operands) << LTy << RTy
5536 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5540 LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
5541 RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
5546 // -- The second and third operands have pointer type, or one has pointer
5547 // type and the other is a null pointer constant, or both are null
5548 // pointer constants, at least one of which is non-integral; pointer
5549 // conversions and qualification conversions are performed to bring them
5550 // to their composite pointer type. The result is of the composite
5552 // -- The second and third operands have pointer to member type, or one has
5553 // pointer to member type and the other is a null pointer constant;
5554 // pointer to member conversions and qualification conversions are
5555 // performed to bring them to a common type, whose cv-qualification
5556 // shall match the cv-qualification of either the second or the third
5557 // operand. The result is of the common type.
5558 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS);
5559 if (!Composite.isNull())
5562 // Similarly, attempt to find composite type of two objective-c pointers.
5563 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc);
5564 if (!Composite.isNull())
5567 // Check if we are using a null with a non-pointer type.
5568 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
5571 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
5572 << LHS.get()->getType() << RHS.get()->getType()
5573 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5577 static FunctionProtoType::ExceptionSpecInfo
5578 mergeExceptionSpecs(Sema &S, FunctionProtoType::ExceptionSpecInfo ESI1,
5579 FunctionProtoType::ExceptionSpecInfo ESI2,
5580 SmallVectorImpl<QualType> &ExceptionTypeStorage) {
5581 ExceptionSpecificationType EST1 = ESI1.Type;
5582 ExceptionSpecificationType EST2 = ESI2.Type;
5584 // If either of them can throw anything, that is the result.
5585 if (EST1 == EST_None) return ESI1;
5586 if (EST2 == EST_None) return ESI2;
5587 if (EST1 == EST_MSAny) return ESI1;
5588 if (EST2 == EST_MSAny) return ESI2;
5590 // If either of them is non-throwing, the result is the other.
5591 if (EST1 == EST_DynamicNone) return ESI2;
5592 if (EST2 == EST_DynamicNone) return ESI1;
5593 if (EST1 == EST_BasicNoexcept) return ESI2;
5594 if (EST2 == EST_BasicNoexcept) return ESI1;
5596 // If either of them is a non-value-dependent computed noexcept, that
5597 // determines the result.
5598 if (EST2 == EST_ComputedNoexcept && ESI2.NoexceptExpr &&
5599 !ESI2.NoexceptExpr->isValueDependent())
5600 return !ESI2.NoexceptExpr->EvaluateKnownConstInt(S.Context) ? ESI2 : ESI1;
5601 if (EST1 == EST_ComputedNoexcept && ESI1.NoexceptExpr &&
5602 !ESI1.NoexceptExpr->isValueDependent())
5603 return !ESI1.NoexceptExpr->EvaluateKnownConstInt(S.Context) ? ESI1 : ESI2;
5604 // If we're left with value-dependent computed noexcept expressions, we're
5605 // stuck. Before C++17, we can just drop the exception specification entirely,
5606 // since it's not actually part of the canonical type. And this should never
5607 // happen in C++17, because it would mean we were computing the composite
5608 // pointer type of dependent types, which should never happen.
5609 if (EST1 == EST_ComputedNoexcept || EST2 == EST_ComputedNoexcept) {
5610 assert(!S.getLangOpts().CPlusPlus1z &&
5611 "computing composite pointer type of dependent types");
5612 return FunctionProtoType::ExceptionSpecInfo();
5615 // Switch over the possibilities so that people adding new values know to
5616 // update this function.
5619 case EST_DynamicNone:
5621 case EST_BasicNoexcept:
5622 case EST_ComputedNoexcept:
5623 llvm_unreachable("handled above");
5626 // This is the fun case: both exception specifications are dynamic. Form
5627 // the union of the two lists.
5628 assert(EST2 == EST_Dynamic && "other cases should already be handled");
5629 llvm::SmallPtrSet<QualType, 8> Found;
5630 for (auto &Exceptions : {ESI1.Exceptions, ESI2.Exceptions})
5631 for (QualType E : Exceptions)
5632 if (Found.insert(S.Context.getCanonicalType(E)).second)
5633 ExceptionTypeStorage.push_back(E);
5635 FunctionProtoType::ExceptionSpecInfo Result(EST_Dynamic);
5636 Result.Exceptions = ExceptionTypeStorage;
5640 case EST_Unevaluated:
5641 case EST_Uninstantiated:
5643 llvm_unreachable("shouldn't see unresolved exception specifications here");
5646 llvm_unreachable("invalid ExceptionSpecificationType");
5649 /// \brief Find a merged pointer type and convert the two expressions to it.
5651 /// This finds the composite pointer type (or member pointer type) for @p E1
5652 /// and @p E2 according to C++1z 5p14. It converts both expressions to this
5653 /// type and returns it.
5654 /// It does not emit diagnostics.
5656 /// \param Loc The location of the operator requiring these two expressions to
5657 /// be converted to the composite pointer type.
5659 /// \param ConvertArgs If \c false, do not convert E1 and E2 to the target type.
5660 QualType Sema::FindCompositePointerType(SourceLocation Loc,
5661 Expr *&E1, Expr *&E2,
5663 assert(getLangOpts().CPlusPlus && "This function assumes C++");
5666 // The composite pointer type of two operands p1 and p2 having types T1
5668 QualType T1 = E1->getType(), T2 = E2->getType();
5670 // where at least one is a pointer or pointer to member type or
5671 // std::nullptr_t is:
5672 bool T1IsPointerLike = T1->isAnyPointerType() || T1->isMemberPointerType() ||
5673 T1->isNullPtrType();
5674 bool T2IsPointerLike = T2->isAnyPointerType() || T2->isMemberPointerType() ||
5675 T2->isNullPtrType();
5676 if (!T1IsPointerLike && !T2IsPointerLike)
5679 // - if both p1 and p2 are null pointer constants, std::nullptr_t;
5680 // This can't actually happen, following the standard, but we also use this
5681 // to implement the end of [expr.conv], which hits this case.
5683 // - if either p1 or p2 is a null pointer constant, T2 or T1, respectively;
5684 if (T1IsPointerLike &&
5685 E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5687 E2 = ImpCastExprToType(E2, T1, T1->isMemberPointerType()
5688 ? CK_NullToMemberPointer
5689 : CK_NullToPointer).get();
5692 if (T2IsPointerLike &&
5693 E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5695 E1 = ImpCastExprToType(E1, T2, T2->isMemberPointerType()
5696 ? CK_NullToMemberPointer
5697 : CK_NullToPointer).get();
5701 // Now both have to be pointers or member pointers.
5702 if (!T1IsPointerLike || !T2IsPointerLike)
5704 assert(!T1->isNullPtrType() && !T2->isNullPtrType() &&
5705 "nullptr_t should be a null pointer constant");
5707 // - if T1 or T2 is "pointer to cv1 void" and the other type is
5708 // "pointer to cv2 T", "pointer to cv12 void", where cv12 is
5709 // the union of cv1 and cv2;
5710 // - if T1 or T2 is "pointer to noexcept function" and the other type is
5711 // "pointer to function", where the function types are otherwise the same,
5712 // "pointer to function";
5713 // FIXME: This rule is defective: it should also permit removing noexcept
5714 // from a pointer to member function. As a Clang extension, we also
5715 // permit removing 'noreturn', so we generalize this rule to;
5716 // - [Clang] If T1 and T2 are both of type "pointer to function" or
5717 // "pointer to member function" and the pointee types can be unified
5718 // by a function pointer conversion, that conversion is applied
5719 // before checking the following rules.
5720 // - if T1 is "pointer to cv1 C1" and T2 is "pointer to cv2 C2", where C1
5721 // is reference-related to C2 or C2 is reference-related to C1 (8.6.3),
5722 // the cv-combined type of T1 and T2 or the cv-combined type of T2 and T1,
5724 // - if T1 is "pointer to member of C1 of type cv1 U1" and T2 is "pointer
5725 // to member of C2 of type cv2 U2" where C1 is reference-related to C2 or
5726 // C2 is reference-related to C1 (8.6.3), the cv-combined type of T2 and
5727 // T1 or the cv-combined type of T1 and T2, respectively;
5728 // - if T1 and T2 are similar types (4.5), the cv-combined type of T1 and
5731 // If looked at in the right way, these bullets all do the same thing.
5732 // What we do here is, we build the two possible cv-combined types, and try
5733 // the conversions in both directions. If only one works, or if the two
5734 // composite types are the same, we have succeeded.
5735 // FIXME: extended qualifiers?
5737 // Note that this will fail to find a composite pointer type for "pointer
5738 // to void" and "pointer to function". We can't actually perform the final
5739 // conversion in this case, even though a composite pointer type formally
5741 SmallVector<unsigned, 4> QualifierUnion;
5742 SmallVector<std::pair<const Type *, const Type *>, 4> MemberOfClass;
5743 QualType Composite1 = T1;
5744 QualType Composite2 = T2;
5745 unsigned NeedConstBefore = 0;
5747 const PointerType *Ptr1, *Ptr2;
5748 if ((Ptr1 = Composite1->getAs<PointerType>()) &&
5749 (Ptr2 = Composite2->getAs<PointerType>())) {
5750 Composite1 = Ptr1->getPointeeType();
5751 Composite2 = Ptr2->getPointeeType();
5753 // If we're allowed to create a non-standard composite type, keep track
5754 // of where we need to fill in additional 'const' qualifiers.
5755 if (Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
5756 NeedConstBefore = QualifierUnion.size();
5758 QualifierUnion.push_back(
5759 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
5760 MemberOfClass.push_back(std::make_pair(nullptr, nullptr));
5764 const MemberPointerType *MemPtr1, *MemPtr2;
5765 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) &&
5766 (MemPtr2 = Composite2->getAs<MemberPointerType>())) {
5767 Composite1 = MemPtr1->getPointeeType();
5768 Composite2 = MemPtr2->getPointeeType();
5770 // If we're allowed to create a non-standard composite type, keep track
5771 // of where we need to fill in additional 'const' qualifiers.
5772 if (Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
5773 NeedConstBefore = QualifierUnion.size();
5775 QualifierUnion.push_back(
5776 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
5777 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(),
5778 MemPtr2->getClass()));
5782 // FIXME: block pointer types?
5784 // Cannot unwrap any more types.
5788 // Apply the function pointer conversion to unify the types. We've already
5789 // unwrapped down to the function types, and we want to merge rather than
5790 // just convert, so do this ourselves rather than calling
5791 // IsFunctionConversion.
5793 // FIXME: In order to match the standard wording as closely as possible, we
5794 // currently only do this under a single level of pointers. Ideally, we would
5795 // allow this in general, and set NeedConstBefore to the relevant depth on
5796 // the side(s) where we changed anything.
5797 if (QualifierUnion.size() == 1) {
5798 if (auto *FPT1 = Composite1->getAs<FunctionProtoType>()) {
5799 if (auto *FPT2 = Composite2->getAs<FunctionProtoType>()) {
5800 FunctionProtoType::ExtProtoInfo EPI1 = FPT1->getExtProtoInfo();
5801 FunctionProtoType::ExtProtoInfo EPI2 = FPT2->getExtProtoInfo();
5803 // The result is noreturn if both operands are.
5805 EPI1.ExtInfo.getNoReturn() && EPI2.ExtInfo.getNoReturn();
5806 EPI1.ExtInfo = EPI1.ExtInfo.withNoReturn(Noreturn);
5807 EPI2.ExtInfo = EPI2.ExtInfo.withNoReturn(Noreturn);
5809 // The result is nothrow if both operands are.
5810 SmallVector<QualType, 8> ExceptionTypeStorage;
5811 EPI1.ExceptionSpec = EPI2.ExceptionSpec =
5812 mergeExceptionSpecs(*this, EPI1.ExceptionSpec, EPI2.ExceptionSpec,
5813 ExceptionTypeStorage);
5815 Composite1 = Context.getFunctionType(FPT1->getReturnType(),
5816 FPT1->getParamTypes(), EPI1);
5817 Composite2 = Context.getFunctionType(FPT2->getReturnType(),
5818 FPT2->getParamTypes(), EPI2);
5823 if (NeedConstBefore) {
5824 // Extension: Add 'const' to qualifiers that come before the first qualifier
5825 // mismatch, so that our (non-standard!) composite type meets the
5826 // requirements of C++ [conv.qual]p4 bullet 3.
5827 for (unsigned I = 0; I != NeedConstBefore; ++I)
5828 if ((QualifierUnion[I] & Qualifiers::Const) == 0)
5829 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const;
5832 // Rewrap the composites as pointers or member pointers with the union CVRs.
5833 auto MOC = MemberOfClass.rbegin();
5834 for (unsigned CVR : llvm::reverse(QualifierUnion)) {
5835 Qualifiers Quals = Qualifiers::fromCVRMask(CVR);
5836 auto Classes = *MOC++;
5837 if (Classes.first && Classes.second) {
5838 // Rebuild member pointer type
5839 Composite1 = Context.getMemberPointerType(
5840 Context.getQualifiedType(Composite1, Quals), Classes.first);
5841 Composite2 = Context.getMemberPointerType(
5842 Context.getQualifiedType(Composite2, Quals), Classes.second);
5844 // Rebuild pointer type
5846 Context.getPointerType(Context.getQualifiedType(Composite1, Quals));
5848 Context.getPointerType(Context.getQualifiedType(Composite2, Quals));
5856 InitializedEntity Entity;
5857 InitializationKind Kind;
5858 InitializationSequence E1ToC, E2ToC;
5861 Conversion(Sema &S, SourceLocation Loc, Expr *&E1, Expr *&E2,
5863 : S(S), E1(E1), E2(E2), Composite(Composite),
5864 Entity(InitializedEntity::InitializeTemporary(Composite)),
5865 Kind(InitializationKind::CreateCopy(Loc, SourceLocation())),
5866 E1ToC(S, Entity, Kind, E1), E2ToC(S, Entity, Kind, E2),
5867 Viable(E1ToC && E2ToC) {}
5870 ExprResult E1Result = E1ToC.Perform(S, Entity, Kind, E1);
5871 if (E1Result.isInvalid())
5873 E1 = E1Result.getAs<Expr>();
5875 ExprResult E2Result = E2ToC.Perform(S, Entity, Kind, E2);
5876 if (E2Result.isInvalid())
5878 E2 = E2Result.getAs<Expr>();
5884 // Try to convert to each composite pointer type.
5885 Conversion C1(*this, Loc, E1, E2, Composite1);
5886 if (C1.Viable && Context.hasSameType(Composite1, Composite2)) {
5887 if (ConvertArgs && C1.perform())
5889 return C1.Composite;
5891 Conversion C2(*this, Loc, E1, E2, Composite2);
5893 if (C1.Viable == C2.Viable) {
5894 // Either Composite1 and Composite2 are viable and are different, or
5895 // neither is viable.
5896 // FIXME: How both be viable and different?
5900 // Convert to the chosen type.
5901 if (ConvertArgs && (C1.Viable ? C1 : C2).perform())
5904 return C1.Viable ? C1.Composite : C2.Composite;
5907 ExprResult Sema::MaybeBindToTemporary(Expr *E) {
5911 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?");
5913 // If the result is a glvalue, we shouldn't bind it.
5917 // In ARC, calls that return a retainable type can return retained,
5918 // in which case we have to insert a consuming cast.
5919 if (getLangOpts().ObjCAutoRefCount &&
5920 E->getType()->isObjCRetainableType()) {
5922 bool ReturnsRetained;
5924 // For actual calls, we compute this by examining the type of the
5926 if (CallExpr *Call = dyn_cast<CallExpr>(E)) {
5927 Expr *Callee = Call->getCallee()->IgnoreParens();
5928 QualType T = Callee->getType();
5930 if (T == Context.BoundMemberTy) {
5931 // Handle pointer-to-members.
5932 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee))
5933 T = BinOp->getRHS()->getType();
5934 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee))
5935 T = Mem->getMemberDecl()->getType();
5938 if (const PointerType *Ptr = T->getAs<PointerType>())
5939 T = Ptr->getPointeeType();
5940 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>())
5941 T = Ptr->getPointeeType();
5942 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>())
5943 T = MemPtr->getPointeeType();
5945 const FunctionType *FTy = T->getAs<FunctionType>();
5946 assert(FTy && "call to value not of function type?");
5947 ReturnsRetained = FTy->getExtInfo().getProducesResult();
5949 // ActOnStmtExpr arranges things so that StmtExprs of retainable
5950 // type always produce a +1 object.
5951 } else if (isa<StmtExpr>(E)) {
5952 ReturnsRetained = true;
5954 // We hit this case with the lambda conversion-to-block optimization;
5955 // we don't want any extra casts here.
5956 } else if (isa<CastExpr>(E) &&
5957 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) {
5960 // For message sends and property references, we try to find an
5961 // actual method. FIXME: we should infer retention by selector in
5962 // cases where we don't have an actual method.
5964 ObjCMethodDecl *D = nullptr;
5965 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) {
5966 D = Send->getMethodDecl();
5967 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) {
5968 D = BoxedExpr->getBoxingMethod();
5969 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) {
5970 D = ArrayLit->getArrayWithObjectsMethod();
5971 } else if (ObjCDictionaryLiteral *DictLit
5972 = dyn_cast<ObjCDictionaryLiteral>(E)) {
5973 D = DictLit->getDictWithObjectsMethod();
5976 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>());
5978 // Don't do reclaims on performSelector calls; despite their
5979 // return type, the invoked method doesn't necessarily actually
5980 // return an object.
5981 if (!ReturnsRetained &&
5982 D && D->getMethodFamily() == OMF_performSelector)
5986 // Don't reclaim an object of Class type.
5987 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType())
5990 Cleanup.setExprNeedsCleanups(true);
5992 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject
5993 : CK_ARCReclaimReturnedObject);
5994 return ImplicitCastExpr::Create(Context, E->getType(), ck, E, nullptr,
5998 if (!getLangOpts().CPlusPlus)
6001 // Search for the base element type (cf. ASTContext::getBaseElementType) with
6002 // a fast path for the common case that the type is directly a RecordType.
6003 const Type *T = Context.getCanonicalType(E->getType().getTypePtr());
6004 const RecordType *RT = nullptr;
6006 switch (T->getTypeClass()) {
6008 RT = cast<RecordType>(T);
6010 case Type::ConstantArray:
6011 case Type::IncompleteArray:
6012 case Type::VariableArray:
6013 case Type::DependentSizedArray:
6014 T = cast<ArrayType>(T)->getElementType().getTypePtr();
6021 // That should be enough to guarantee that this type is complete, if we're
6022 // not processing a decltype expression.
6023 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
6024 if (RD->isInvalidDecl() || RD->isDependentContext())
6027 bool IsDecltype = ExprEvalContexts.back().IsDecltype;
6028 CXXDestructorDecl *Destructor = IsDecltype ? nullptr : LookupDestructor(RD);
6031 MarkFunctionReferenced(E->getExprLoc(), Destructor);
6032 CheckDestructorAccess(E->getExprLoc(), Destructor,
6033 PDiag(diag::err_access_dtor_temp)
6035 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
6038 // If destructor is trivial, we can avoid the extra copy.
6039 if (Destructor->isTrivial())
6042 // We need a cleanup, but we don't need to remember the temporary.
6043 Cleanup.setExprNeedsCleanups(true);
6046 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor);
6047 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E);
6050 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind);
6056 Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) {
6057 if (SubExpr.isInvalid())
6060 return MaybeCreateExprWithCleanups(SubExpr.get());
6063 Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) {
6064 assert(SubExpr && "subexpression can't be null!");
6066 CleanupVarDeclMarking();
6068 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects;
6069 assert(ExprCleanupObjects.size() >= FirstCleanup);
6070 assert(Cleanup.exprNeedsCleanups() ||
6071 ExprCleanupObjects.size() == FirstCleanup);
6072 if (!Cleanup.exprNeedsCleanups())
6075 auto Cleanups = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup,
6076 ExprCleanupObjects.size() - FirstCleanup);
6078 auto *E = ExprWithCleanups::Create(
6079 Context, SubExpr, Cleanup.cleanupsHaveSideEffects(), Cleanups);
6080 DiscardCleanupsInEvaluationContext();
6085 Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) {
6086 assert(SubStmt && "sub-statement can't be null!");
6088 CleanupVarDeclMarking();
6090 if (!Cleanup.exprNeedsCleanups())
6093 // FIXME: In order to attach the temporaries, wrap the statement into
6094 // a StmtExpr; currently this is only used for asm statements.
6095 // This is hacky, either create a new CXXStmtWithTemporaries statement or
6096 // a new AsmStmtWithTemporaries.
6097 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, SubStmt,
6100 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(),
6102 return MaybeCreateExprWithCleanups(E);
6105 /// Process the expression contained within a decltype. For such expressions,
6106 /// certain semantic checks on temporaries are delayed until this point, and
6107 /// are omitted for the 'topmost' call in the decltype expression. If the
6108 /// topmost call bound a temporary, strip that temporary off the expression.
6109 ExprResult Sema::ActOnDecltypeExpression(Expr *E) {
6110 assert(ExprEvalContexts.back().IsDecltype && "not in a decltype expression");
6112 // C++11 [expr.call]p11:
6113 // If a function call is a prvalue of object type,
6114 // -- if the function call is either
6115 // -- the operand of a decltype-specifier, or
6116 // -- the right operand of a comma operator that is the operand of a
6117 // decltype-specifier,
6118 // a temporary object is not introduced for the prvalue.
6120 // Recursively rebuild ParenExprs and comma expressions to strip out the
6121 // outermost CXXBindTemporaryExpr, if any.
6122 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
6123 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr());
6124 if (SubExpr.isInvalid())
6126 if (SubExpr.get() == PE->getSubExpr())
6128 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.get());
6130 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
6131 if (BO->getOpcode() == BO_Comma) {
6132 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS());
6133 if (RHS.isInvalid())
6135 if (RHS.get() == BO->getRHS())
6137 return new (Context) BinaryOperator(
6138 BO->getLHS(), RHS.get(), BO_Comma, BO->getType(), BO->getValueKind(),
6139 BO->getObjectKind(), BO->getOperatorLoc(), BO->isFPContractable());
6143 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E);
6144 CallExpr *TopCall = TopBind ? dyn_cast<CallExpr>(TopBind->getSubExpr())
6151 // Disable the special decltype handling now.
6152 ExprEvalContexts.back().IsDecltype = false;
6154 // In MS mode, don't perform any extra checking of call return types within a
6155 // decltype expression.
6156 if (getLangOpts().MSVCCompat)
6159 // Perform the semantic checks we delayed until this point.
6160 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size();
6162 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I];
6163 if (Call == TopCall)
6166 if (CheckCallReturnType(Call->getCallReturnType(Context),
6167 Call->getLocStart(),
6168 Call, Call->getDirectCallee()))
6172 // Now all relevant types are complete, check the destructors are accessible
6173 // and non-deleted, and annotate them on the temporaries.
6174 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size();
6176 CXXBindTemporaryExpr *Bind =
6177 ExprEvalContexts.back().DelayedDecltypeBinds[I];
6178 if (Bind == TopBind)
6181 CXXTemporary *Temp = Bind->getTemporary();
6184 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
6185 CXXDestructorDecl *Destructor = LookupDestructor(RD);
6186 Temp->setDestructor(Destructor);
6188 MarkFunctionReferenced(Bind->getExprLoc(), Destructor);
6189 CheckDestructorAccess(Bind->getExprLoc(), Destructor,
6190 PDiag(diag::err_access_dtor_temp)
6191 << Bind->getType());
6192 if (DiagnoseUseOfDecl(Destructor, Bind->getExprLoc()))
6195 // We need a cleanup, but we don't need to remember the temporary.
6196 Cleanup.setExprNeedsCleanups(true);
6199 // Possibly strip off the top CXXBindTemporaryExpr.
6203 /// Note a set of 'operator->' functions that were used for a member access.
6204 static void noteOperatorArrows(Sema &S,
6205 ArrayRef<FunctionDecl *> OperatorArrows) {
6206 unsigned SkipStart = OperatorArrows.size(), SkipCount = 0;
6207 // FIXME: Make this configurable?
6209 if (OperatorArrows.size() > Limit) {
6210 // Produce Limit-1 normal notes and one 'skipping' note.
6211 SkipStart = (Limit - 1) / 2 + (Limit - 1) % 2;
6212 SkipCount = OperatorArrows.size() - (Limit - 1);
6215 for (unsigned I = 0; I < OperatorArrows.size(); /**/) {
6216 if (I == SkipStart) {
6217 S.Diag(OperatorArrows[I]->getLocation(),
6218 diag::note_operator_arrows_suppressed)
6222 S.Diag(OperatorArrows[I]->getLocation(), diag::note_operator_arrow_here)
6223 << OperatorArrows[I]->getCallResultType();
6229 ExprResult Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base,
6230 SourceLocation OpLoc,
6231 tok::TokenKind OpKind,
6232 ParsedType &ObjectType,
6233 bool &MayBePseudoDestructor) {
6234 // Since this might be a postfix expression, get rid of ParenListExprs.
6235 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base);
6236 if (Result.isInvalid()) return ExprError();
6237 Base = Result.get();
6239 Result = CheckPlaceholderExpr(Base);
6240 if (Result.isInvalid()) return ExprError();
6241 Base = Result.get();
6243 QualType BaseType = Base->getType();
6244 MayBePseudoDestructor = false;
6245 if (BaseType->isDependentType()) {
6246 // If we have a pointer to a dependent type and are using the -> operator,
6247 // the object type is the type that the pointer points to. We might still
6248 // have enough information about that type to do something useful.
6249 if (OpKind == tok::arrow)
6250 if (const PointerType *Ptr = BaseType->getAs<PointerType>())
6251 BaseType = Ptr->getPointeeType();
6253 ObjectType = ParsedType::make(BaseType);
6254 MayBePseudoDestructor = true;
6258 // C++ [over.match.oper]p8:
6259 // [...] When operator->returns, the operator-> is applied to the value
6260 // returned, with the original second operand.
6261 if (OpKind == tok::arrow) {
6262 QualType StartingType = BaseType;
6263 bool NoArrowOperatorFound = false;
6264 bool FirstIteration = true;
6265 FunctionDecl *CurFD = dyn_cast<FunctionDecl>(CurContext);
6266 // The set of types we've considered so far.
6267 llvm::SmallPtrSet<CanQualType,8> CTypes;
6268 SmallVector<FunctionDecl*, 8> OperatorArrows;
6269 CTypes.insert(Context.getCanonicalType(BaseType));
6271 while (BaseType->isRecordType()) {
6272 if (OperatorArrows.size() >= getLangOpts().ArrowDepth) {
6273 Diag(OpLoc, diag::err_operator_arrow_depth_exceeded)
6274 << StartingType << getLangOpts().ArrowDepth << Base->getSourceRange();
6275 noteOperatorArrows(*this, OperatorArrows);
6276 Diag(OpLoc, diag::note_operator_arrow_depth)
6277 << getLangOpts().ArrowDepth;
6281 Result = BuildOverloadedArrowExpr(
6283 // When in a template specialization and on the first loop iteration,
6284 // potentially give the default diagnostic (with the fixit in a
6285 // separate note) instead of having the error reported back to here
6286 // and giving a diagnostic with a fixit attached to the error itself.
6287 (FirstIteration && CurFD && CurFD->isFunctionTemplateSpecialization())
6289 : &NoArrowOperatorFound);
6290 if (Result.isInvalid()) {
6291 if (NoArrowOperatorFound) {
6292 if (FirstIteration) {
6293 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
6294 << BaseType << 1 << Base->getSourceRange()
6295 << FixItHint::CreateReplacement(OpLoc, ".");
6296 OpKind = tok::period;
6299 Diag(OpLoc, diag::err_typecheck_member_reference_arrow)
6300 << BaseType << Base->getSourceRange();
6301 CallExpr *CE = dyn_cast<CallExpr>(Base);
6302 if (Decl *CD = (CE ? CE->getCalleeDecl() : nullptr)) {
6303 Diag(CD->getLocStart(),
6304 diag::note_member_reference_arrow_from_operator_arrow);
6309 Base = Result.get();
6310 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base))
6311 OperatorArrows.push_back(OpCall->getDirectCallee());
6312 BaseType = Base->getType();
6313 CanQualType CBaseType = Context.getCanonicalType(BaseType);
6314 if (!CTypes.insert(CBaseType).second) {
6315 Diag(OpLoc, diag::err_operator_arrow_circular) << StartingType;
6316 noteOperatorArrows(*this, OperatorArrows);
6319 FirstIteration = false;
6322 if (OpKind == tok::arrow &&
6323 (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()))
6324 BaseType = BaseType->getPointeeType();
6327 // Objective-C properties allow "." access on Objective-C pointer types,
6328 // so adjust the base type to the object type itself.
6329 if (BaseType->isObjCObjectPointerType())
6330 BaseType = BaseType->getPointeeType();
6332 // C++ [basic.lookup.classref]p2:
6333 // [...] If the type of the object expression is of pointer to scalar
6334 // type, the unqualified-id is looked up in the context of the complete
6335 // postfix-expression.
6337 // This also indicates that we could be parsing a pseudo-destructor-name.
6338 // Note that Objective-C class and object types can be pseudo-destructor
6339 // expressions or normal member (ivar or property) access expressions, and
6340 // it's legal for the type to be incomplete if this is a pseudo-destructor
6341 // call. We'll do more incomplete-type checks later in the lookup process,
6342 // so just skip this check for ObjC types.
6343 if (BaseType->isObjCObjectOrInterfaceType()) {
6344 ObjectType = ParsedType::make(BaseType);
6345 MayBePseudoDestructor = true;
6347 } else if (!BaseType->isRecordType()) {
6348 ObjectType = nullptr;
6349 MayBePseudoDestructor = true;
6353 // The object type must be complete (or dependent), or
6354 // C++11 [expr.prim.general]p3:
6355 // Unlike the object expression in other contexts, *this is not required to
6356 // be of complete type for purposes of class member access (5.2.5) outside
6357 // the member function body.
6358 if (!BaseType->isDependentType() &&
6359 !isThisOutsideMemberFunctionBody(BaseType) &&
6360 RequireCompleteType(OpLoc, BaseType, diag::err_incomplete_member_access))
6363 // C++ [basic.lookup.classref]p2:
6364 // If the id-expression in a class member access (5.2.5) is an
6365 // unqualified-id, and the type of the object expression is of a class
6366 // type C (or of pointer to a class type C), the unqualified-id is looked
6367 // up in the scope of class C. [...]
6368 ObjectType = ParsedType::make(BaseType);
6372 static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base,
6373 tok::TokenKind& OpKind, SourceLocation OpLoc) {
6374 if (Base->hasPlaceholderType()) {
6375 ExprResult result = S.CheckPlaceholderExpr(Base);
6376 if (result.isInvalid()) return true;
6377 Base = result.get();
6379 ObjectType = Base->getType();
6381 // C++ [expr.pseudo]p2:
6382 // The left-hand side of the dot operator shall be of scalar type. The
6383 // left-hand side of the arrow operator shall be of pointer to scalar type.
6384 // This scalar type is the object type.
6385 // Note that this is rather different from the normal handling for the
6387 if (OpKind == tok::arrow) {
6388 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) {
6389 ObjectType = Ptr->getPointeeType();
6390 } else if (!Base->isTypeDependent()) {
6391 // The user wrote "p->" when they probably meant "p."; fix it.
6392 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
6393 << ObjectType << true
6394 << FixItHint::CreateReplacement(OpLoc, ".");
6395 if (S.isSFINAEContext())
6398 OpKind = tok::period;
6405 ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base,
6406 SourceLocation OpLoc,
6407 tok::TokenKind OpKind,
6408 const CXXScopeSpec &SS,
6409 TypeSourceInfo *ScopeTypeInfo,
6410 SourceLocation CCLoc,
6411 SourceLocation TildeLoc,
6412 PseudoDestructorTypeStorage Destructed) {
6413 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo();
6415 QualType ObjectType;
6416 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6419 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() &&
6420 !ObjectType->isVectorType()) {
6421 if (getLangOpts().MSVCCompat && ObjectType->isVoidType())
6422 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange();
6424 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar)
6425 << ObjectType << Base->getSourceRange();
6430 // C++ [expr.pseudo]p2:
6431 // [...] The cv-unqualified versions of the object type and of the type
6432 // designated by the pseudo-destructor-name shall be the same type.
6433 if (DestructedTypeInfo) {
6434 QualType DestructedType = DestructedTypeInfo->getType();
6435 SourceLocation DestructedTypeStart
6436 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin();
6437 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) {
6438 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) {
6439 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch)
6440 << ObjectType << DestructedType << Base->getSourceRange()
6441 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
6443 // Recover by setting the destructed type to the object type.
6444 DestructedType = ObjectType;
6445 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType,
6446 DestructedTypeStart);
6447 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6448 } else if (DestructedType.getObjCLifetime() !=
6449 ObjectType.getObjCLifetime()) {
6451 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) {
6452 // Okay: just pretend that the user provided the correctly-qualified
6455 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals)
6456 << ObjectType << DestructedType << Base->getSourceRange()
6457 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
6460 // Recover by setting the destructed type to the object type.
6461 DestructedType = ObjectType;
6462 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType,
6463 DestructedTypeStart);
6464 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6469 // C++ [expr.pseudo]p2:
6470 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the
6473 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name
6475 // shall designate the same scalar type.
6476 if (ScopeTypeInfo) {
6477 QualType ScopeType = ScopeTypeInfo->getType();
6478 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() &&
6479 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) {
6481 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(),
6482 diag::err_pseudo_dtor_type_mismatch)
6483 << ObjectType << ScopeType << Base->getSourceRange()
6484 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange();
6486 ScopeType = QualType();
6487 ScopeTypeInfo = nullptr;
6492 = new (Context) CXXPseudoDestructorExpr(Context, Base,
6493 OpKind == tok::arrow, OpLoc,
6494 SS.getWithLocInContext(Context),
6503 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
6504 SourceLocation OpLoc,
6505 tok::TokenKind OpKind,
6507 UnqualifiedId &FirstTypeName,
6508 SourceLocation CCLoc,
6509 SourceLocation TildeLoc,
6510 UnqualifiedId &SecondTypeName) {
6511 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
6512 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
6513 "Invalid first type name in pseudo-destructor");
6514 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
6515 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
6516 "Invalid second type name in pseudo-destructor");
6518 QualType ObjectType;
6519 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6522 // Compute the object type that we should use for name lookup purposes. Only
6523 // record types and dependent types matter.
6524 ParsedType ObjectTypePtrForLookup;
6526 if (ObjectType->isRecordType())
6527 ObjectTypePtrForLookup = ParsedType::make(ObjectType);
6528 else if (ObjectType->isDependentType())
6529 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy);
6532 // Convert the name of the type being destructed (following the ~) into a
6533 // type (with source-location information).
6534 QualType DestructedType;
6535 TypeSourceInfo *DestructedTypeInfo = nullptr;
6536 PseudoDestructorTypeStorage Destructed;
6537 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) {
6538 ParsedType T = getTypeName(*SecondTypeName.Identifier,
6539 SecondTypeName.StartLocation,
6540 S, &SS, true, false, ObjectTypePtrForLookup);
6542 ((SS.isSet() && !computeDeclContext(SS, false)) ||
6543 (!SS.isSet() && ObjectType->isDependentType()))) {
6544 // The name of the type being destroyed is a dependent name, and we
6545 // couldn't find anything useful in scope. Just store the identifier and
6546 // it's location, and we'll perform (qualified) name lookup again at
6547 // template instantiation time.
6548 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier,
6549 SecondTypeName.StartLocation);
6551 Diag(SecondTypeName.StartLocation,
6552 diag::err_pseudo_dtor_destructor_non_type)
6553 << SecondTypeName.Identifier << ObjectType;
6554 if (isSFINAEContext())
6557 // Recover by assuming we had the right type all along.
6558 DestructedType = ObjectType;
6560 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo);
6562 // Resolve the template-id to a type.
6563 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId;
6564 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
6565 TemplateId->NumArgs);
6566 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
6567 TemplateId->TemplateKWLoc,
6568 TemplateId->Template,
6569 TemplateId->TemplateNameLoc,
6570 TemplateId->LAngleLoc,
6572 TemplateId->RAngleLoc);
6573 if (T.isInvalid() || !T.get()) {
6574 // Recover by assuming we had the right type all along.
6575 DestructedType = ObjectType;
6577 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo);
6580 // If we've performed some kind of recovery, (re-)build the type source
6582 if (!DestructedType.isNull()) {
6583 if (!DestructedTypeInfo)
6584 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType,
6585 SecondTypeName.StartLocation);
6586 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6589 // Convert the name of the scope type (the type prior to '::') into a type.
6590 TypeSourceInfo *ScopeTypeInfo = nullptr;
6592 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
6593 FirstTypeName.Identifier) {
6594 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) {
6595 ParsedType T = getTypeName(*FirstTypeName.Identifier,
6596 FirstTypeName.StartLocation,
6597 S, &SS, true, false, ObjectTypePtrForLookup);
6599 Diag(FirstTypeName.StartLocation,
6600 diag::err_pseudo_dtor_destructor_non_type)
6601 << FirstTypeName.Identifier << ObjectType;
6603 if (isSFINAEContext())
6606 // Just drop this type. It's unnecessary anyway.
6607 ScopeType = QualType();
6609 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo);
6611 // Resolve the template-id to a type.
6612 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId;
6613 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
6614 TemplateId->NumArgs);
6615 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
6616 TemplateId->TemplateKWLoc,
6617 TemplateId->Template,
6618 TemplateId->TemplateNameLoc,
6619 TemplateId->LAngleLoc,
6621 TemplateId->RAngleLoc);
6622 if (T.isInvalid() || !T.get()) {
6623 // Recover by dropping this type.
6624 ScopeType = QualType();
6626 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo);
6630 if (!ScopeType.isNull() && !ScopeTypeInfo)
6631 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType,
6632 FirstTypeName.StartLocation);
6635 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS,
6636 ScopeTypeInfo, CCLoc, TildeLoc,
6640 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
6641 SourceLocation OpLoc,
6642 tok::TokenKind OpKind,
6643 SourceLocation TildeLoc,
6644 const DeclSpec& DS) {
6645 QualType ObjectType;
6646 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6649 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc(),
6653 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T);
6654 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc());
6655 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T);
6656 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo);
6658 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(),
6659 nullptr, SourceLocation(), TildeLoc,
6663 ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl,
6664 CXXConversionDecl *Method,
6665 bool HadMultipleCandidates) {
6666 if (Method->getParent()->isLambda() &&
6667 Method->getConversionType()->isBlockPointerType()) {
6668 // This is a lambda coversion to block pointer; check if the argument
6671 CastExpr *CE = dyn_cast<CastExpr>(SubE);
6672 if (CE && CE->getCastKind() == CK_NoOp)
6673 SubE = CE->getSubExpr();
6674 SubE = SubE->IgnoreParens();
6675 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE))
6676 SubE = BE->getSubExpr();
6677 if (isa<LambdaExpr>(SubE)) {
6678 // For the conversion to block pointer on a lambda expression, we
6679 // construct a special BlockLiteral instead; this doesn't really make
6680 // a difference in ARC, but outside of ARC the resulting block literal
6681 // follows the normal lifetime rules for block literals instead of being
6683 DiagnosticErrorTrap Trap(Diags);
6684 PushExpressionEvaluationContext(PotentiallyEvaluated);
6685 ExprResult Exp = BuildBlockForLambdaConversion(E->getExprLoc(),
6688 PopExpressionEvaluationContext();
6690 if (Exp.isInvalid())
6691 Diag(E->getExprLoc(), diag::note_lambda_to_block_conv);
6696 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/nullptr,
6698 if (Exp.isInvalid())
6701 MemberExpr *ME = new (Context) MemberExpr(
6702 Exp.get(), /*IsArrow=*/false, SourceLocation(), Method, SourceLocation(),
6703 Context.BoundMemberTy, VK_RValue, OK_Ordinary);
6704 if (HadMultipleCandidates)
6705 ME->setHadMultipleCandidates(true);
6706 MarkMemberReferenced(ME);
6708 QualType ResultType = Method->getReturnType();
6709 ExprValueKind VK = Expr::getValueKindForType(ResultType);
6710 ResultType = ResultType.getNonLValueExprType(Context);
6712 CXXMemberCallExpr *CE =
6713 new (Context) CXXMemberCallExpr(Context, ME, None, ResultType, VK,
6714 Exp.get()->getLocEnd());
6716 if (CheckFunctionCall(Method, CE,
6717 Method->getType()->castAs<FunctionProtoType>()))
6723 ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand,
6724 SourceLocation RParen) {
6725 // If the operand is an unresolved lookup expression, the expression is ill-
6726 // formed per [over.over]p1, because overloaded function names cannot be used
6727 // without arguments except in explicit contexts.
6728 ExprResult R = CheckPlaceholderExpr(Operand);
6732 // The operand may have been modified when checking the placeholder type.
6735 if (ActiveTemplateInstantiations.empty() &&
6736 Operand->HasSideEffects(Context, false)) {
6737 // The expression operand for noexcept is in an unevaluated expression
6738 // context, so side effects could result in unintended consequences.
6739 Diag(Operand->getExprLoc(), diag::warn_side_effects_unevaluated_context);
6742 CanThrowResult CanThrow = canThrow(Operand);
6743 return new (Context)
6744 CXXNoexceptExpr(Context.BoolTy, Operand, CanThrow, KeyLoc, RParen);
6747 ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation,
6748 Expr *Operand, SourceLocation RParen) {
6749 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen);
6752 static bool IsSpecialDiscardedValue(Expr *E) {
6753 // In C++11, discarded-value expressions of a certain form are special,
6754 // according to [expr]p10:
6755 // The lvalue-to-rvalue conversion (4.1) is applied only if the
6756 // expression is an lvalue of volatile-qualified type and it has
6757 // one of the following forms:
6758 E = E->IgnoreParens();
6760 // - id-expression (5.1.1),
6761 if (isa<DeclRefExpr>(E))
6764 // - subscripting (5.2.1),
6765 if (isa<ArraySubscriptExpr>(E))
6768 // - class member access (5.2.5),
6769 if (isa<MemberExpr>(E))
6772 // - indirection (5.3.1),
6773 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E))
6774 if (UO->getOpcode() == UO_Deref)
6777 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
6778 // - pointer-to-member operation (5.5),
6779 if (BO->isPtrMemOp())
6782 // - comma expression (5.18) where the right operand is one of the above.
6783 if (BO->getOpcode() == BO_Comma)
6784 return IsSpecialDiscardedValue(BO->getRHS());
6787 // - conditional expression (5.16) where both the second and the third
6788 // operands are one of the above, or
6789 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E))
6790 return IsSpecialDiscardedValue(CO->getTrueExpr()) &&
6791 IsSpecialDiscardedValue(CO->getFalseExpr());
6792 // The related edge case of "*x ?: *x".
6793 if (BinaryConditionalOperator *BCO =
6794 dyn_cast<BinaryConditionalOperator>(E)) {
6795 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(BCO->getTrueExpr()))
6796 return IsSpecialDiscardedValue(OVE->getSourceExpr()) &&
6797 IsSpecialDiscardedValue(BCO->getFalseExpr());
6800 // Objective-C++ extensions to the rule.
6801 if (isa<PseudoObjectExpr>(E) || isa<ObjCIvarRefExpr>(E))
6807 /// Perform the conversions required for an expression used in a
6808 /// context that ignores the result.
6809 ExprResult Sema::IgnoredValueConversions(Expr *E) {
6810 if (E->hasPlaceholderType()) {
6811 ExprResult result = CheckPlaceholderExpr(E);
6812 if (result.isInvalid()) return E;
6817 // [Except in specific positions,] an lvalue that does not have
6818 // array type is converted to the value stored in the
6819 // designated object (and is no longer an lvalue).
6820 if (E->isRValue()) {
6821 // In C, function designators (i.e. expressions of function type)
6822 // are r-values, but we still want to do function-to-pointer decay
6823 // on them. This is both technically correct and convenient for
6825 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType())
6826 return DefaultFunctionArrayConversion(E);
6831 if (getLangOpts().CPlusPlus) {
6832 // The C++11 standard defines the notion of a discarded-value expression;
6833 // normally, we don't need to do anything to handle it, but if it is a
6834 // volatile lvalue with a special form, we perform an lvalue-to-rvalue
6836 if (getLangOpts().CPlusPlus11 && E->isGLValue() &&
6837 E->getType().isVolatileQualified() &&
6838 IsSpecialDiscardedValue(E)) {
6839 ExprResult Res = DefaultLvalueConversion(E);
6840 if (Res.isInvalid())
6846 // If the expression is a prvalue after this optional conversion, the
6847 // temporary materialization conversion is applied.
6849 // We skip this step: IR generation is able to synthesize the storage for
6850 // itself in the aggregate case, and adding the extra node to the AST is
6852 // FIXME: We don't emit lifetime markers for the temporaries due to this.
6853 // FIXME: Do any other AST consumers care about this?
6857 // GCC seems to also exclude expressions of incomplete enum type.
6858 if (const EnumType *T = E->getType()->getAs<EnumType>()) {
6859 if (!T->getDecl()->isComplete()) {
6860 // FIXME: stupid workaround for a codegen bug!
6861 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).get();
6866 ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
6867 if (Res.isInvalid())
6871 if (!E->getType()->isVoidType())
6872 RequireCompleteType(E->getExprLoc(), E->getType(),
6873 diag::err_incomplete_type);
6877 // If we can unambiguously determine whether Var can never be used
6878 // in a constant expression, return true.
6879 // - if the variable and its initializer are non-dependent, then
6880 // we can unambiguously check if the variable is a constant expression.
6881 // - if the initializer is not value dependent - we can determine whether
6882 // it can be used to initialize a constant expression. If Init can not
6883 // be used to initialize a constant expression we conclude that Var can
6884 // never be a constant expression.
6885 // - FXIME: if the initializer is dependent, we can still do some analysis and
6886 // identify certain cases unambiguously as non-const by using a Visitor:
6887 // - such as those that involve odr-use of a ParmVarDecl, involve a new
6888 // delete, lambda-expr, dynamic-cast, reinterpret-cast etc...
6889 static inline bool VariableCanNeverBeAConstantExpression(VarDecl *Var,
6890 ASTContext &Context) {
6891 if (isa<ParmVarDecl>(Var)) return true;
6892 const VarDecl *DefVD = nullptr;
6894 // If there is no initializer - this can not be a constant expression.
6895 if (!Var->getAnyInitializer(DefVD)) return true;
6897 if (DefVD->isWeak()) return false;
6898 EvaluatedStmt *Eval = DefVD->ensureEvaluatedStmt();
6900 Expr *Init = cast<Expr>(Eval->Value);
6902 if (Var->getType()->isDependentType() || Init->isValueDependent()) {
6903 // FIXME: Teach the constant evaluator to deal with the non-dependent parts
6904 // of value-dependent expressions, and use it here to determine whether the
6905 // initializer is a potential constant expression.
6909 return !IsVariableAConstantExpression(Var, Context);
6912 /// \brief Check if the current lambda has any potential captures
6913 /// that must be captured by any of its enclosing lambdas that are ready to
6914 /// capture. If there is a lambda that can capture a nested
6915 /// potential-capture, go ahead and do so. Also, check to see if any
6916 /// variables are uncaptureable or do not involve an odr-use so do not
6917 /// need to be captured.
6919 static void CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(
6920 Expr *const FE, LambdaScopeInfo *const CurrentLSI, Sema &S) {
6922 assert(!S.isUnevaluatedContext());
6923 assert(S.CurContext->isDependentContext());
6925 DeclContext *DC = S.CurContext;
6926 while (DC && isa<CapturedDecl>(DC))
6927 DC = DC->getParent();
6929 CurrentLSI->CallOperator == DC &&
6930 "The current call operator must be synchronized with Sema's CurContext");
6933 const bool IsFullExprInstantiationDependent = FE->isInstantiationDependent();
6935 ArrayRef<const FunctionScopeInfo *> FunctionScopesArrayRef(
6936 S.FunctionScopes.data(), S.FunctionScopes.size());
6938 // All the potentially captureable variables in the current nested
6939 // lambda (within a generic outer lambda), must be captured by an
6940 // outer lambda that is enclosed within a non-dependent context.
6941 const unsigned NumPotentialCaptures =
6942 CurrentLSI->getNumPotentialVariableCaptures();
6943 for (unsigned I = 0; I != NumPotentialCaptures; ++I) {
6944 Expr *VarExpr = nullptr;
6945 VarDecl *Var = nullptr;
6946 CurrentLSI->getPotentialVariableCapture(I, Var, VarExpr);
6947 // If the variable is clearly identified as non-odr-used and the full
6948 // expression is not instantiation dependent, only then do we not
6949 // need to check enclosing lambda's for speculative captures.
6951 // Even though 'x' is not odr-used, it should be captured.
6953 // const int x = 10;
6954 // auto L = [=](auto a) {
6958 if (CurrentLSI->isVariableExprMarkedAsNonODRUsed(VarExpr) &&
6959 !IsFullExprInstantiationDependent)
6962 // If we have a capture-capable lambda for the variable, go ahead and
6963 // capture the variable in that lambda (and all its enclosing lambdas).
6964 if (const Optional<unsigned> Index =
6965 getStackIndexOfNearestEnclosingCaptureCapableLambda(
6966 FunctionScopesArrayRef, Var, S)) {
6967 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
6968 MarkVarDeclODRUsed(Var, VarExpr->getExprLoc(), S,
6969 &FunctionScopeIndexOfCapturableLambda);
6971 const bool IsVarNeverAConstantExpression =
6972 VariableCanNeverBeAConstantExpression(Var, S.Context);
6973 if (!IsFullExprInstantiationDependent || IsVarNeverAConstantExpression) {
6974 // This full expression is not instantiation dependent or the variable
6975 // can not be used in a constant expression - which means
6976 // this variable must be odr-used here, so diagnose a
6977 // capture violation early, if the variable is un-captureable.
6978 // This is purely for diagnosing errors early. Otherwise, this
6979 // error would get diagnosed when the lambda becomes capture ready.
6980 QualType CaptureType, DeclRefType;
6981 SourceLocation ExprLoc = VarExpr->getExprLoc();
6982 if (S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
6983 /*EllipsisLoc*/ SourceLocation(),
6984 /*BuildAndDiagnose*/false, CaptureType,
6985 DeclRefType, nullptr)) {
6986 // We will never be able to capture this variable, and we need
6987 // to be able to in any and all instantiations, so diagnose it.
6988 S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
6989 /*EllipsisLoc*/ SourceLocation(),
6990 /*BuildAndDiagnose*/true, CaptureType,
6991 DeclRefType, nullptr);
6996 // Check if 'this' needs to be captured.
6997 if (CurrentLSI->hasPotentialThisCapture()) {
6998 // If we have a capture-capable lambda for 'this', go ahead and capture
6999 // 'this' in that lambda (and all its enclosing lambdas).
7000 if (const Optional<unsigned> Index =
7001 getStackIndexOfNearestEnclosingCaptureCapableLambda(
7002 FunctionScopesArrayRef, /*0 is 'this'*/ nullptr, S)) {
7003 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
7004 S.CheckCXXThisCapture(CurrentLSI->PotentialThisCaptureLocation,
7005 /*Explicit*/ false, /*BuildAndDiagnose*/ true,
7006 &FunctionScopeIndexOfCapturableLambda);
7010 // Reset all the potential captures at the end of each full-expression.
7011 CurrentLSI->clearPotentialCaptures();
7014 static ExprResult attemptRecovery(Sema &SemaRef,
7015 const TypoCorrectionConsumer &Consumer,
7016 const TypoCorrection &TC) {
7017 LookupResult R(SemaRef, Consumer.getLookupResult().getLookupNameInfo(),
7018 Consumer.getLookupResult().getLookupKind());
7019 const CXXScopeSpec *SS = Consumer.getSS();
7022 // Use an approprate CXXScopeSpec for building the expr.
7023 if (auto *NNS = TC.getCorrectionSpecifier())
7024 NewSS.MakeTrivial(SemaRef.Context, NNS, TC.getCorrectionRange());
7025 else if (SS && !TC.WillReplaceSpecifier())
7028 if (auto *ND = TC.getFoundDecl()) {
7029 R.setLookupName(ND->getDeclName());
7031 if (ND->isCXXClassMember()) {
7032 // Figure out the correct naming class to add to the LookupResult.
7033 CXXRecordDecl *Record = nullptr;
7034 if (auto *NNS = TC.getCorrectionSpecifier())
7035 Record = NNS->getAsType()->getAsCXXRecordDecl();
7038 dyn_cast<CXXRecordDecl>(ND->getDeclContext()->getRedeclContext());
7040 R.setNamingClass(Record);
7042 // Detect and handle the case where the decl might be an implicit
7044 bool MightBeImplicitMember;
7045 if (!Consumer.isAddressOfOperand())
7046 MightBeImplicitMember = true;
7047 else if (!NewSS.isEmpty())
7048 MightBeImplicitMember = false;
7049 else if (R.isOverloadedResult())
7050 MightBeImplicitMember = false;
7051 else if (R.isUnresolvableResult())
7052 MightBeImplicitMember = true;
7054 MightBeImplicitMember = isa<FieldDecl>(ND) ||
7055 isa<IndirectFieldDecl>(ND) ||
7056 isa<MSPropertyDecl>(ND);
7058 if (MightBeImplicitMember)
7059 return SemaRef.BuildPossibleImplicitMemberExpr(
7060 NewSS, /*TemplateKWLoc*/ SourceLocation(), R,
7061 /*TemplateArgs*/ nullptr, /*S*/ nullptr);
7062 } else if (auto *Ivar = dyn_cast<ObjCIvarDecl>(ND)) {
7063 return SemaRef.LookupInObjCMethod(R, Consumer.getScope(),
7064 Ivar->getIdentifier());
7068 return SemaRef.BuildDeclarationNameExpr(NewSS, R, /*NeedsADL*/ false,
7069 /*AcceptInvalidDecl*/ true);
7073 class FindTypoExprs : public RecursiveASTVisitor<FindTypoExprs> {
7074 llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs;
7077 explicit FindTypoExprs(llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs)
7078 : TypoExprs(TypoExprs) {}
7079 bool VisitTypoExpr(TypoExpr *TE) {
7080 TypoExprs.insert(TE);
7085 class TransformTypos : public TreeTransform<TransformTypos> {
7086 typedef TreeTransform<TransformTypos> BaseTransform;
7088 VarDecl *InitDecl; // A decl to avoid as a correction because it is in the
7089 // process of being initialized.
7090 llvm::function_ref<ExprResult(Expr *)> ExprFilter;
7091 llvm::SmallSetVector<TypoExpr *, 2> TypoExprs, AmbiguousTypoExprs;
7092 llvm::SmallDenseMap<TypoExpr *, ExprResult, 2> TransformCache;
7093 llvm::SmallDenseMap<OverloadExpr *, Expr *, 4> OverloadResolution;
7095 /// \brief Emit diagnostics for all of the TypoExprs encountered.
7096 /// If the TypoExprs were successfully corrected, then the diagnostics should
7097 /// suggest the corrections. Otherwise the diagnostics will not suggest
7098 /// anything (having been passed an empty TypoCorrection).
7099 void EmitAllDiagnostics() {
7100 for (auto E : TypoExprs) {
7101 TypoExpr *TE = cast<TypoExpr>(E);
7102 auto &State = SemaRef.getTypoExprState(TE);
7103 if (State.DiagHandler) {
7104 TypoCorrection TC = State.Consumer->getCurrentCorrection();
7105 ExprResult Replacement = TransformCache[TE];
7107 // Extract the NamedDecl from the transformed TypoExpr and add it to the
7108 // TypoCorrection, replacing the existing decls. This ensures the right
7109 // NamedDecl is used in diagnostics e.g. in the case where overload
7110 // resolution was used to select one from several possible decls that
7111 // had been stored in the TypoCorrection.
7112 if (auto *ND = getDeclFromExpr(
7113 Replacement.isInvalid() ? nullptr : Replacement.get()))
7114 TC.setCorrectionDecl(ND);
7116 State.DiagHandler(TC);
7118 SemaRef.clearDelayedTypo(TE);
7122 /// \brief If corrections for the first TypoExpr have been exhausted for a
7123 /// given combination of the other TypoExprs, retry those corrections against
7124 /// the next combination of substitutions for the other TypoExprs by advancing
7125 /// to the next potential correction of the second TypoExpr. For the second
7126 /// and subsequent TypoExprs, if its stream of corrections has been exhausted,
7127 /// the stream is reset and the next TypoExpr's stream is advanced by one (a
7128 /// TypoExpr's correction stream is advanced by removing the TypoExpr from the
7129 /// TransformCache). Returns true if there is still any untried combinations
7131 bool CheckAndAdvanceTypoExprCorrectionStreams() {
7132 for (auto TE : TypoExprs) {
7133 auto &State = SemaRef.getTypoExprState(TE);
7134 TransformCache.erase(TE);
7135 if (!State.Consumer->finished())
7137 State.Consumer->resetCorrectionStream();
7142 NamedDecl *getDeclFromExpr(Expr *E) {
7143 if (auto *OE = dyn_cast_or_null<OverloadExpr>(E))
7144 E = OverloadResolution[OE];
7148 if (auto *DRE = dyn_cast<DeclRefExpr>(E))
7149 return DRE->getFoundDecl();
7150 if (auto *ME = dyn_cast<MemberExpr>(E))
7151 return ME->getFoundDecl();
7152 // FIXME: Add any other expr types that could be be seen by the delayed typo
7153 // correction TreeTransform for which the corresponding TypoCorrection could
7154 // contain multiple decls.
7158 ExprResult TryTransform(Expr *E) {
7159 Sema::SFINAETrap Trap(SemaRef);
7160 ExprResult Res = TransformExpr(E);
7161 if (Trap.hasErrorOccurred() || Res.isInvalid())
7164 return ExprFilter(Res.get());
7168 TransformTypos(Sema &SemaRef, VarDecl *InitDecl, llvm::function_ref<ExprResult(Expr *)> Filter)
7169 : BaseTransform(SemaRef), InitDecl(InitDecl), ExprFilter(Filter) {}
7171 ExprResult RebuildCallExpr(Expr *Callee, SourceLocation LParenLoc,
7173 SourceLocation RParenLoc,
7174 Expr *ExecConfig = nullptr) {
7175 auto Result = BaseTransform::RebuildCallExpr(Callee, LParenLoc, Args,
7176 RParenLoc, ExecConfig);
7177 if (auto *OE = dyn_cast<OverloadExpr>(Callee)) {
7178 if (Result.isUsable()) {
7179 Expr *ResultCall = Result.get();
7180 if (auto *BE = dyn_cast<CXXBindTemporaryExpr>(ResultCall))
7181 ResultCall = BE->getSubExpr();
7182 if (auto *CE = dyn_cast<CallExpr>(ResultCall))
7183 OverloadResolution[OE] = CE->getCallee();
7189 ExprResult TransformLambdaExpr(LambdaExpr *E) { return Owned(E); }
7191 ExprResult TransformBlockExpr(BlockExpr *E) { return Owned(E); }
7193 ExprResult Transform(Expr *E) {
7196 Res = TryTransform(E);
7198 // Exit if either the transform was valid or if there were no TypoExprs
7199 // to transform that still have any untried correction candidates..
7200 if (!Res.isInvalid() ||
7201 !CheckAndAdvanceTypoExprCorrectionStreams())
7205 // Ensure none of the TypoExprs have multiple typo correction candidates
7206 // with the same edit length that pass all the checks and filters.
7207 // TODO: Properly handle various permutations of possible corrections when
7208 // there is more than one potentially ambiguous typo correction.
7209 // Also, disable typo correction while attempting the transform when
7210 // handling potentially ambiguous typo corrections as any new TypoExprs will
7211 // have been introduced by the application of one of the correction
7212 // candidates and add little to no value if corrected.
7213 SemaRef.DisableTypoCorrection = true;
7214 while (!AmbiguousTypoExprs.empty()) {
7215 auto TE = AmbiguousTypoExprs.back();
7216 auto Cached = TransformCache[TE];
7217 auto &State = SemaRef.getTypoExprState(TE);
7218 State.Consumer->saveCurrentPosition();
7219 TransformCache.erase(TE);
7220 if (!TryTransform(E).isInvalid()) {
7221 State.Consumer->resetCorrectionStream();
7222 TransformCache.erase(TE);
7226 AmbiguousTypoExprs.remove(TE);
7227 State.Consumer->restoreSavedPosition();
7228 TransformCache[TE] = Cached;
7230 SemaRef.DisableTypoCorrection = false;
7232 // Ensure that all of the TypoExprs within the current Expr have been found.
7233 if (!Res.isUsable())
7234 FindTypoExprs(TypoExprs).TraverseStmt(E);
7236 EmitAllDiagnostics();
7241 ExprResult TransformTypoExpr(TypoExpr *E) {
7242 // If the TypoExpr hasn't been seen before, record it. Otherwise, return the
7243 // cached transformation result if there is one and the TypoExpr isn't the
7244 // first one that was encountered.
7245 auto &CacheEntry = TransformCache[E];
7246 if (!TypoExprs.insert(E) && !CacheEntry.isUnset()) {
7250 auto &State = SemaRef.getTypoExprState(E);
7251 assert(State.Consumer && "Cannot transform a cleared TypoExpr");
7253 // For the first TypoExpr and an uncached TypoExpr, find the next likely
7254 // typo correction and return it.
7255 while (TypoCorrection TC = State.Consumer->getNextCorrection()) {
7256 if (InitDecl && TC.getFoundDecl() == InitDecl)
7258 // FIXME: If we would typo-correct to an invalid declaration, it's
7259 // probably best to just suppress all errors from this typo correction.
7260 ExprResult NE = State.RecoveryHandler ?
7261 State.RecoveryHandler(SemaRef, E, TC) :
7262 attemptRecovery(SemaRef, *State.Consumer, TC);
7263 if (!NE.isInvalid()) {
7264 // Check whether there may be a second viable correction with the same
7265 // edit distance; if so, remember this TypoExpr may have an ambiguous
7266 // correction so it can be more thoroughly vetted later.
7267 TypoCorrection Next;
7268 if ((Next = State.Consumer->peekNextCorrection()) &&
7269 Next.getEditDistance(false) == TC.getEditDistance(false)) {
7270 AmbiguousTypoExprs.insert(E);
7272 AmbiguousTypoExprs.remove(E);
7274 assert(!NE.isUnset() &&
7275 "Typo was transformed into a valid-but-null ExprResult");
7276 return CacheEntry = NE;
7279 return CacheEntry = ExprError();
7285 Sema::CorrectDelayedTyposInExpr(Expr *E, VarDecl *InitDecl,
7286 llvm::function_ref<ExprResult(Expr *)> Filter) {
7287 // If the current evaluation context indicates there are uncorrected typos
7288 // and the current expression isn't guaranteed to not have typos, try to
7289 // resolve any TypoExpr nodes that might be in the expression.
7290 if (E && !ExprEvalContexts.empty() && ExprEvalContexts.back().NumTypos &&
7291 (E->isTypeDependent() || E->isValueDependent() ||
7292 E->isInstantiationDependent())) {
7293 auto TyposInContext = ExprEvalContexts.back().NumTypos;
7294 assert(TyposInContext < ~0U && "Recursive call of CorrectDelayedTyposInExpr");
7295 ExprEvalContexts.back().NumTypos = ~0U;
7296 auto TyposResolved = DelayedTypos.size();
7297 auto Result = TransformTypos(*this, InitDecl, Filter).Transform(E);
7298 ExprEvalContexts.back().NumTypos = TyposInContext;
7299 TyposResolved -= DelayedTypos.size();
7300 if (Result.isInvalid() || Result.get() != E) {
7301 ExprEvalContexts.back().NumTypos -= TyposResolved;
7304 assert(TyposResolved == 0 && "Corrected typo but got same Expr back?");
7309 ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC,
7310 bool DiscardedValue,
7312 bool IsLambdaInitCaptureInitializer) {
7313 ExprResult FullExpr = FE;
7315 if (!FullExpr.get())
7318 // If we are an init-expression in a lambdas init-capture, we should not
7319 // diagnose an unexpanded pack now (will be diagnosed once lambda-expr
7320 // containing full-expression is done).
7321 // template<class ... Ts> void test(Ts ... t) {
7322 // test([&a(t)]() { <-- (t) is an init-expr that shouldn't be diagnosed now.
7326 // FIXME: This is a hack. It would be better if we pushed the lambda scope
7327 // when we parse the lambda introducer, and teach capturing (but not
7328 // unexpanded pack detection) to walk over LambdaScopeInfos which don't have a
7329 // corresponding class yet (that is, have LambdaScopeInfo either represent a
7330 // lambda where we've entered the introducer but not the body, or represent a
7331 // lambda where we've entered the body, depending on where the
7332 // parser/instantiation has got to).
7333 if (!IsLambdaInitCaptureInitializer &&
7334 DiagnoseUnexpandedParameterPack(FullExpr.get()))
7337 // Top-level expressions default to 'id' when we're in a debugger.
7338 if (DiscardedValue && getLangOpts().DebuggerCastResultToId &&
7339 FullExpr.get()->getType() == Context.UnknownAnyTy) {
7340 FullExpr = forceUnknownAnyToType(FullExpr.get(), Context.getObjCIdType());
7341 if (FullExpr.isInvalid())
7345 if (DiscardedValue) {
7346 FullExpr = CheckPlaceholderExpr(FullExpr.get());
7347 if (FullExpr.isInvalid())
7350 FullExpr = IgnoredValueConversions(FullExpr.get());
7351 if (FullExpr.isInvalid())
7355 FullExpr = CorrectDelayedTyposInExpr(FullExpr.get());
7356 if (FullExpr.isInvalid())
7359 CheckCompletedExpr(FullExpr.get(), CC, IsConstexpr);
7361 // At the end of this full expression (which could be a deeply nested
7362 // lambda), if there is a potential capture within the nested lambda,
7363 // have the outer capture-able lambda try and capture it.
7364 // Consider the following code:
7365 // void f(int, int);
7366 // void f(const int&, double);
7368 // const int x = 10, y = 20;
7369 // auto L = [=](auto a) {
7370 // auto M = [=](auto b) {
7371 // f(x, b); <-- requires x to be captured by L and M
7372 // f(y, a); <-- requires y to be captured by L, but not all Ms
7377 // FIXME: Also consider what happens for something like this that involves
7378 // the gnu-extension statement-expressions or even lambda-init-captures:
7381 // auto L = [&](auto a) {
7382 // +n + ({ 0; a; });
7386 // Here, we see +n, and then the full-expression 0; ends, so we don't
7387 // capture n (and instead remove it from our list of potential captures),
7388 // and then the full-expression +n + ({ 0; }); ends, but it's too late
7389 // for us to see that we need to capture n after all.
7391 LambdaScopeInfo *const CurrentLSI =
7392 getCurLambda(/*IgnoreCapturedRegions=*/true);
7393 // FIXME: PR 17877 showed that getCurLambda() can return a valid pointer
7394 // even if CurContext is not a lambda call operator. Refer to that Bug Report
7395 // for an example of the code that might cause this asynchrony.
7396 // By ensuring we are in the context of a lambda's call operator
7397 // we can fix the bug (we only need to check whether we need to capture
7398 // if we are within a lambda's body); but per the comments in that
7399 // PR, a proper fix would entail :
7400 // "Alternative suggestion:
7401 // - Add to Sema an integer holding the smallest (outermost) scope
7402 // index that we are *lexically* within, and save/restore/set to
7403 // FunctionScopes.size() in InstantiatingTemplate's
7404 // constructor/destructor.
7405 // - Teach the handful of places that iterate over FunctionScopes to
7406 // stop at the outermost enclosing lexical scope."
7407 DeclContext *DC = CurContext;
7408 while (DC && isa<CapturedDecl>(DC))
7409 DC = DC->getParent();
7410 const bool IsInLambdaDeclContext = isLambdaCallOperator(DC);
7411 if (IsInLambdaDeclContext && CurrentLSI &&
7412 CurrentLSI->hasPotentialCaptures() && !FullExpr.isInvalid())
7413 CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(FE, CurrentLSI,
7415 return MaybeCreateExprWithCleanups(FullExpr);
7418 StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) {
7419 if (!FullStmt) return StmtError();
7421 return MaybeCreateStmtWithCleanups(FullStmt);
7424 Sema::IfExistsResult
7425 Sema::CheckMicrosoftIfExistsSymbol(Scope *S,
7427 const DeclarationNameInfo &TargetNameInfo) {
7428 DeclarationName TargetName = TargetNameInfo.getName();
7430 return IER_DoesNotExist;
7432 // If the name itself is dependent, then the result is dependent.
7433 if (TargetName.isDependentName())
7434 return IER_Dependent;
7436 // Do the redeclaration lookup in the current scope.
7437 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName,
7438 Sema::NotForRedeclaration);
7439 LookupParsedName(R, S, &SS);
7440 R.suppressDiagnostics();
7442 switch (R.getResultKind()) {
7443 case LookupResult::Found:
7444 case LookupResult::FoundOverloaded:
7445 case LookupResult::FoundUnresolvedValue:
7446 case LookupResult::Ambiguous:
7449 case LookupResult::NotFound:
7450 return IER_DoesNotExist;
7452 case LookupResult::NotFoundInCurrentInstantiation:
7453 return IER_Dependent;
7456 llvm_unreachable("Invalid LookupResult Kind!");
7459 Sema::IfExistsResult
7460 Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc,
7461 bool IsIfExists, CXXScopeSpec &SS,
7462 UnqualifiedId &Name) {
7463 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
7465 // Check for an unexpanded parameter pack.
7466 auto UPPC = IsIfExists ? UPPC_IfExists : UPPC_IfNotExists;
7467 if (DiagnoseUnexpandedParameterPack(SS, UPPC) ||
7468 DiagnoseUnexpandedParameterPack(TargetNameInfo, UPPC))
7471 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo);