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 *RD = Ty->getAsCXXRecordDecl();
527 if (const auto *Uuid = RD->getMostRecentDecl()->getAttr<UuidAttr>()) {
528 UuidAttrs.insert(Uuid);
532 // __uuidof can grab UUIDs from template arguments.
533 if (const auto *CTSD = dyn_cast<ClassTemplateSpecializationDecl>(RD)) {
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 if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
687 Diag(OpLoc, diag::err_omp_simd_region_cannot_use_stmt) << "throw";
689 if (Ex && !Ex->isTypeDependent()) {
690 QualType ExceptionObjectTy = Context.getExceptionObjectType(Ex->getType());
691 if (CheckCXXThrowOperand(OpLoc, ExceptionObjectTy, Ex))
694 // Initialize the exception result. This implicitly weeds out
695 // abstract types or types with inaccessible copy constructors.
697 // C++0x [class.copymove]p31:
698 // When certain criteria are met, an implementation is allowed to omit the
699 // copy/move construction of a class object [...]
701 // - in a throw-expression, when the operand is the name of a
702 // non-volatile automatic object (other than a function or
704 // parameter) whose scope does not extend beyond the end of the
705 // innermost enclosing try-block (if there is one), the copy/move
706 // operation from the operand to the exception object (15.1) can be
707 // omitted by constructing the automatic object directly into the
709 const VarDecl *NRVOVariable = nullptr;
710 if (IsThrownVarInScope)
711 NRVOVariable = getCopyElisionCandidate(QualType(), Ex, false);
713 InitializedEntity Entity = InitializedEntity::InitializeException(
714 OpLoc, ExceptionObjectTy,
715 /*NRVO=*/NRVOVariable != nullptr);
716 ExprResult Res = PerformMoveOrCopyInitialization(
717 Entity, NRVOVariable, QualType(), Ex, IsThrownVarInScope);
724 CXXThrowExpr(Ex, Context.VoidTy, OpLoc, IsThrownVarInScope);
728 collectPublicBases(CXXRecordDecl *RD,
729 llvm::DenseMap<CXXRecordDecl *, unsigned> &SubobjectsSeen,
730 llvm::SmallPtrSetImpl<CXXRecordDecl *> &VBases,
731 llvm::SetVector<CXXRecordDecl *> &PublicSubobjectsSeen,
732 bool ParentIsPublic) {
733 for (const CXXBaseSpecifier &BS : RD->bases()) {
734 CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
736 // Virtual bases constitute the same subobject. Non-virtual bases are
737 // always distinct subobjects.
739 NewSubobject = VBases.insert(BaseDecl).second;
744 ++SubobjectsSeen[BaseDecl];
746 // Only add subobjects which have public access throughout the entire chain.
747 bool PublicPath = ParentIsPublic && BS.getAccessSpecifier() == AS_public;
749 PublicSubobjectsSeen.insert(BaseDecl);
751 // Recurse on to each base subobject.
752 collectPublicBases(BaseDecl, SubobjectsSeen, VBases, PublicSubobjectsSeen,
757 static void getUnambiguousPublicSubobjects(
758 CXXRecordDecl *RD, llvm::SmallVectorImpl<CXXRecordDecl *> &Objects) {
759 llvm::DenseMap<CXXRecordDecl *, unsigned> SubobjectsSeen;
760 llvm::SmallSet<CXXRecordDecl *, 2> VBases;
761 llvm::SetVector<CXXRecordDecl *> PublicSubobjectsSeen;
762 SubobjectsSeen[RD] = 1;
763 PublicSubobjectsSeen.insert(RD);
764 collectPublicBases(RD, SubobjectsSeen, VBases, PublicSubobjectsSeen,
765 /*ParentIsPublic=*/true);
767 for (CXXRecordDecl *PublicSubobject : PublicSubobjectsSeen) {
768 // Skip ambiguous objects.
769 if (SubobjectsSeen[PublicSubobject] > 1)
772 Objects.push_back(PublicSubobject);
776 /// CheckCXXThrowOperand - Validate the operand of a throw.
777 bool Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc,
778 QualType ExceptionObjectTy, Expr *E) {
779 // If the type of the exception would be an incomplete type or a pointer
780 // to an incomplete type other than (cv) void the program is ill-formed.
781 QualType Ty = ExceptionObjectTy;
782 bool isPointer = false;
783 if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
784 Ty = Ptr->getPointeeType();
787 if (!isPointer || !Ty->isVoidType()) {
788 if (RequireCompleteType(ThrowLoc, Ty,
789 isPointer ? diag::err_throw_incomplete_ptr
790 : diag::err_throw_incomplete,
791 E->getSourceRange()))
794 if (RequireNonAbstractType(ThrowLoc, ExceptionObjectTy,
795 diag::err_throw_abstract_type, E))
799 // If the exception has class type, we need additional handling.
800 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
804 // If we are throwing a polymorphic class type or pointer thereof,
805 // exception handling will make use of the vtable.
806 MarkVTableUsed(ThrowLoc, RD);
808 // If a pointer is thrown, the referenced object will not be destroyed.
812 // If the class has a destructor, we must be able to call it.
813 if (!RD->hasIrrelevantDestructor()) {
814 if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
815 MarkFunctionReferenced(E->getExprLoc(), Destructor);
816 CheckDestructorAccess(E->getExprLoc(), Destructor,
817 PDiag(diag::err_access_dtor_exception) << Ty);
818 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
823 // The MSVC ABI creates a list of all types which can catch the exception
824 // object. This list also references the appropriate copy constructor to call
825 // if the object is caught by value and has a non-trivial copy constructor.
826 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
827 // We are only interested in the public, unambiguous bases contained within
828 // the exception object. Bases which are ambiguous or otherwise
829 // inaccessible are not catchable types.
830 llvm::SmallVector<CXXRecordDecl *, 2> UnambiguousPublicSubobjects;
831 getUnambiguousPublicSubobjects(RD, UnambiguousPublicSubobjects);
833 for (CXXRecordDecl *Subobject : UnambiguousPublicSubobjects) {
834 // Attempt to lookup the copy constructor. Various pieces of machinery
835 // will spring into action, like template instantiation, which means this
836 // cannot be a simple walk of the class's decls. Instead, we must perform
837 // lookup and overload resolution.
838 CXXConstructorDecl *CD = LookupCopyingConstructor(Subobject, 0);
842 // Mark the constructor referenced as it is used by this throw expression.
843 MarkFunctionReferenced(E->getExprLoc(), CD);
845 // Skip this copy constructor if it is trivial, we don't need to record it
846 // in the catchable type data.
850 // The copy constructor is non-trivial, create a mapping from this class
851 // type to this constructor.
852 // N.B. The selection of copy constructor is not sensitive to this
853 // particular throw-site. Lookup will be performed at the catch-site to
854 // ensure that the copy constructor is, in fact, accessible (via
855 // friendship or any other means).
856 Context.addCopyConstructorForExceptionObject(Subobject, CD);
858 // We don't keep the instantiated default argument expressions around so
859 // we must rebuild them here.
860 for (unsigned I = 1, E = CD->getNumParams(); I != E; ++I) {
861 // Skip any default arguments that we've already instantiated.
862 if (Context.getDefaultArgExprForConstructor(CD, I))
866 BuildCXXDefaultArgExpr(ThrowLoc, CD, CD->getParamDecl(I)).get();
867 Context.addDefaultArgExprForConstructor(CD, I, DefaultArg);
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 upto 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 auto Result = BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc);
1220 // Avoid creating a non-type-dependent expression that contains typos.
1221 // Non-type-dependent expressions are liable to be discarded without
1222 // checking for embedded typos.
1223 if (!Result.isInvalid() && Result.get()->isInstantiationDependent() &&
1224 !Result.get()->isTypeDependent())
1225 Result = CorrectDelayedTyposInExpr(Result.get());
1229 /// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
1230 /// Can be interpreted either as function-style casting ("int(x)")
1231 /// or class type construction ("ClassType(x,y,z)")
1232 /// or creation of a value-initialized type ("int()").
1234 Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo,
1235 SourceLocation LParenLoc,
1237 SourceLocation RParenLoc) {
1238 QualType Ty = TInfo->getType();
1239 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc();
1241 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(Exprs)) {
1242 return CXXUnresolvedConstructExpr::Create(Context, TInfo, LParenLoc, Exprs,
1246 bool ListInitialization = LParenLoc.isInvalid();
1247 assert((!ListInitialization || (Exprs.size() == 1 && isa<InitListExpr>(Exprs[0])))
1248 && "List initialization must have initializer list as expression.");
1249 SourceRange FullRange = SourceRange(TyBeginLoc,
1250 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc);
1252 // C++ [expr.type.conv]p1:
1253 // If the expression list is a single expression, the type conversion
1254 // expression is equivalent (in definedness, and if defined in meaning) to the
1255 // corresponding cast expression.
1256 if (Exprs.size() == 1 && !ListInitialization) {
1257 Expr *Arg = Exprs[0];
1258 return BuildCXXFunctionalCastExpr(TInfo, LParenLoc, Arg, RParenLoc);
1261 // C++14 [expr.type.conv]p2: The expression T(), where T is a
1262 // simple-type-specifier or typename-specifier for a non-array complete
1263 // object type or the (possibly cv-qualified) void type, creates a prvalue
1264 // of the specified type, whose value is that produced by value-initializing
1265 // an object of type T.
1266 QualType ElemTy = Ty;
1267 if (Ty->isArrayType()) {
1268 if (!ListInitialization)
1269 return ExprError(Diag(TyBeginLoc,
1270 diag::err_value_init_for_array_type) << FullRange);
1271 ElemTy = Context.getBaseElementType(Ty);
1274 if (!ListInitialization && Ty->isFunctionType())
1275 return ExprError(Diag(TyBeginLoc, diag::err_value_init_for_function_type)
1278 if (!Ty->isVoidType() &&
1279 RequireCompleteType(TyBeginLoc, ElemTy,
1280 diag::err_invalid_incomplete_type_use, FullRange))
1283 if (RequireNonAbstractType(TyBeginLoc, Ty,
1284 diag::err_allocation_of_abstract_type))
1287 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo);
1288 InitializationKind Kind =
1289 Exprs.size() ? ListInitialization
1290 ? InitializationKind::CreateDirectList(TyBeginLoc)
1291 : InitializationKind::CreateDirect(TyBeginLoc, LParenLoc, RParenLoc)
1292 : InitializationKind::CreateValue(TyBeginLoc, LParenLoc, RParenLoc);
1293 InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
1294 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Exprs);
1296 if (Result.isInvalid() || !ListInitialization)
1299 Expr *Inner = Result.get();
1300 if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Inner))
1301 Inner = BTE->getSubExpr();
1302 if (!isa<CXXTemporaryObjectExpr>(Inner)) {
1303 // If we created a CXXTemporaryObjectExpr, that node also represents the
1304 // functional cast. Otherwise, create an explicit cast to represent
1305 // the syntactic form of a functional-style cast that was used here.
1307 // FIXME: Creating a CXXFunctionalCastExpr around a CXXConstructExpr
1308 // would give a more consistent AST representation than using a
1309 // CXXTemporaryObjectExpr. It's also weird that the functional cast
1310 // is sometimes handled by initialization and sometimes not.
1311 QualType ResultType = Result.get()->getType();
1312 Result = CXXFunctionalCastExpr::Create(
1313 Context, ResultType, Expr::getValueKindForType(TInfo->getType()), TInfo,
1314 CK_NoOp, Result.get(), /*Path=*/nullptr, LParenLoc, RParenLoc);
1320 /// doesUsualArrayDeleteWantSize - Answers whether the usual
1321 /// operator delete[] for the given type has a size_t parameter.
1322 static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc,
1323 QualType allocType) {
1324 const RecordType *record =
1325 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>();
1326 if (!record) return false;
1328 // Try to find an operator delete[] in class scope.
1330 DeclarationName deleteName =
1331 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete);
1332 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName);
1333 S.LookupQualifiedName(ops, record->getDecl());
1335 // We're just doing this for information.
1336 ops.suppressDiagnostics();
1338 // Very likely: there's no operator delete[].
1339 if (ops.empty()) return false;
1341 // If it's ambiguous, it should be illegal to call operator delete[]
1342 // on this thing, so it doesn't matter if we allocate extra space or not.
1343 if (ops.isAmbiguous()) return false;
1345 LookupResult::Filter filter = ops.makeFilter();
1346 while (filter.hasNext()) {
1347 NamedDecl *del = filter.next()->getUnderlyingDecl();
1349 // C++0x [basic.stc.dynamic.deallocation]p2:
1350 // A template instance is never a usual deallocation function,
1351 // regardless of its signature.
1352 if (isa<FunctionTemplateDecl>(del)) {
1357 // C++0x [basic.stc.dynamic.deallocation]p2:
1358 // If class T does not declare [an operator delete[] with one
1359 // parameter] but does declare a member deallocation function
1360 // named operator delete[] with exactly two parameters, the
1361 // second of which has type std::size_t, then this function
1362 // is a usual deallocation function.
1363 if (!cast<CXXMethodDecl>(del)->isUsualDeallocationFunction()) {
1370 if (!ops.isSingleResult()) return false;
1372 const FunctionDecl *del = cast<FunctionDecl>(ops.getFoundDecl());
1373 return (del->getNumParams() == 2);
1376 /// \brief Parsed a C++ 'new' expression (C++ 5.3.4).
1379 /// @code new (memory) int[size][4] @endcode
1381 /// @code ::new Foo(23, "hello") @endcode
1383 /// \param StartLoc The first location of the expression.
1384 /// \param UseGlobal True if 'new' was prefixed with '::'.
1385 /// \param PlacementLParen Opening paren of the placement arguments.
1386 /// \param PlacementArgs Placement new arguments.
1387 /// \param PlacementRParen Closing paren of the placement arguments.
1388 /// \param TypeIdParens If the type is in parens, the source range.
1389 /// \param D The type to be allocated, as well as array dimensions.
1390 /// \param Initializer The initializing expression or initializer-list, or null
1391 /// if there is none.
1393 Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
1394 SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
1395 SourceLocation PlacementRParen, SourceRange TypeIdParens,
1396 Declarator &D, Expr *Initializer) {
1397 bool TypeContainsAuto = D.getDeclSpec().containsPlaceholderType();
1399 Expr *ArraySize = nullptr;
1400 // If the specified type is an array, unwrap it and save the expression.
1401 if (D.getNumTypeObjects() > 0 &&
1402 D.getTypeObject(0).Kind == DeclaratorChunk::Array) {
1403 DeclaratorChunk &Chunk = D.getTypeObject(0);
1404 if (TypeContainsAuto)
1405 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto)
1406 << D.getSourceRange());
1407 if (Chunk.Arr.hasStatic)
1408 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
1409 << D.getSourceRange());
1410 if (!Chunk.Arr.NumElts)
1411 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
1412 << D.getSourceRange());
1414 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
1415 D.DropFirstTypeObject();
1418 // Every dimension shall be of constant size.
1420 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
1421 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array)
1424 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr;
1425 if (Expr *NumElts = (Expr *)Array.NumElts) {
1426 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
1427 if (getLangOpts().CPlusPlus14) {
1428 // C++1y [expr.new]p6: Every constant-expression in a noptr-new-declarator
1429 // shall be a converted constant expression (5.19) of type std::size_t
1430 // and shall evaluate to a strictly positive value.
1431 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
1432 assert(IntWidth && "Builtin type of size 0?");
1433 llvm::APSInt Value(IntWidth);
1435 = CheckConvertedConstantExpression(NumElts, Context.getSizeType(), Value,
1440 = VerifyIntegerConstantExpression(NumElts, nullptr,
1441 diag::err_new_array_nonconst)
1451 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/nullptr);
1452 QualType AllocType = TInfo->getType();
1453 if (D.isInvalidType())
1456 SourceRange DirectInitRange;
1457 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer))
1458 DirectInitRange = List->getSourceRange();
1460 return BuildCXXNew(SourceRange(StartLoc, D.getLocEnd()), UseGlobal,
1473 static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style,
1477 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init))
1478 return PLE->getNumExprs() == 0;
1479 if (isa<ImplicitValueInitExpr>(Init))
1481 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init))
1482 return !CCE->isListInitialization() &&
1483 CCE->getConstructor()->isDefaultConstructor();
1484 else if (Style == CXXNewExpr::ListInit) {
1485 assert(isa<InitListExpr>(Init) &&
1486 "Shouldn't create list CXXConstructExprs for arrays.");
1493 Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
1494 SourceLocation PlacementLParen,
1495 MultiExprArg PlacementArgs,
1496 SourceLocation PlacementRParen,
1497 SourceRange TypeIdParens,
1499 TypeSourceInfo *AllocTypeInfo,
1501 SourceRange DirectInitRange,
1503 bool TypeMayContainAuto) {
1504 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange();
1505 SourceLocation StartLoc = Range.getBegin();
1507 CXXNewExpr::InitializationStyle initStyle;
1508 if (DirectInitRange.isValid()) {
1509 assert(Initializer && "Have parens but no initializer.");
1510 initStyle = CXXNewExpr::CallInit;
1511 } else if (Initializer && isa<InitListExpr>(Initializer))
1512 initStyle = CXXNewExpr::ListInit;
1514 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) ||
1515 isa<CXXConstructExpr>(Initializer)) &&
1516 "Initializer expression that cannot have been implicitly created.");
1517 initStyle = CXXNewExpr::NoInit;
1520 Expr **Inits = &Initializer;
1521 unsigned NumInits = Initializer ? 1 : 0;
1522 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) {
1523 assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init");
1524 Inits = List->getExprs();
1525 NumInits = List->getNumExprs();
1528 // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
1529 if (TypeMayContainAuto && AllocType->isUndeducedType()) {
1530 if (initStyle == CXXNewExpr::NoInit || NumInits == 0)
1531 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg)
1532 << AllocType << TypeRange);
1533 if (initStyle == CXXNewExpr::ListInit ||
1534 (NumInits == 1 && isa<InitListExpr>(Inits[0])))
1535 return ExprError(Diag(Inits[0]->getLocStart(),
1536 diag::err_auto_new_list_init)
1537 << AllocType << TypeRange);
1539 Expr *FirstBad = Inits[1];
1540 return ExprError(Diag(FirstBad->getLocStart(),
1541 diag::err_auto_new_ctor_multiple_expressions)
1542 << AllocType << TypeRange);
1544 Expr *Deduce = Inits[0];
1545 QualType DeducedType;
1546 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed)
1547 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure)
1548 << AllocType << Deduce->getType()
1549 << TypeRange << Deduce->getSourceRange());
1550 if (DeducedType.isNull())
1552 AllocType = DeducedType;
1555 // Per C++0x [expr.new]p5, the type being constructed may be a
1556 // typedef of an array type.
1558 if (const ConstantArrayType *Array
1559 = Context.getAsConstantArrayType(AllocType)) {
1560 ArraySize = IntegerLiteral::Create(Context, Array->getSize(),
1561 Context.getSizeType(),
1562 TypeRange.getEnd());
1563 AllocType = Array->getElementType();
1567 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange))
1570 if (initStyle == CXXNewExpr::ListInit &&
1571 isStdInitializerList(AllocType, nullptr)) {
1572 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(),
1573 diag::warn_dangling_std_initializer_list)
1574 << /*at end of FE*/0 << Inits[0]->getSourceRange();
1577 // In ARC, infer 'retaining' for the allocated
1578 if (getLangOpts().ObjCAutoRefCount &&
1579 AllocType.getObjCLifetime() == Qualifiers::OCL_None &&
1580 AllocType->isObjCLifetimeType()) {
1581 AllocType = Context.getLifetimeQualifiedType(AllocType,
1582 AllocType->getObjCARCImplicitLifetime());
1585 QualType ResultType = Context.getPointerType(AllocType);
1587 if (ArraySize && ArraySize->getType()->isNonOverloadPlaceholderType()) {
1588 ExprResult result = CheckPlaceholderExpr(ArraySize);
1589 if (result.isInvalid()) return ExprError();
1590 ArraySize = result.get();
1592 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have
1593 // integral or enumeration type with a non-negative value."
1594 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped
1595 // enumeration type, or a class type for which a single non-explicit
1596 // conversion function to integral or unscoped enumeration type exists.
1597 // C++1y [expr.new]p6: The expression [...] is implicitly converted to
1599 if (ArraySize && !ArraySize->isTypeDependent()) {
1600 ExprResult ConvertedSize;
1601 if (getLangOpts().CPlusPlus14) {
1602 assert(Context.getTargetInfo().getIntWidth() && "Builtin type of size 0?");
1604 ConvertedSize = PerformImplicitConversion(ArraySize, Context.getSizeType(),
1607 if (!ConvertedSize.isInvalid() &&
1608 ArraySize->getType()->getAs<RecordType>())
1609 // Diagnose the compatibility of this conversion.
1610 Diag(StartLoc, diag::warn_cxx98_compat_array_size_conversion)
1611 << ArraySize->getType() << 0 << "'size_t'";
1613 class SizeConvertDiagnoser : public ICEConvertDiagnoser {
1618 SizeConvertDiagnoser(Expr *ArraySize)
1619 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false, false, false),
1620 ArraySize(ArraySize) {}
1622 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
1623 QualType T) override {
1624 return S.Diag(Loc, diag::err_array_size_not_integral)
1625 << S.getLangOpts().CPlusPlus11 << T;
1628 SemaDiagnosticBuilder diagnoseIncomplete(
1629 Sema &S, SourceLocation Loc, QualType T) override {
1630 return S.Diag(Loc, diag::err_array_size_incomplete_type)
1631 << T << ArraySize->getSourceRange();
1634 SemaDiagnosticBuilder diagnoseExplicitConv(
1635 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
1636 return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy;
1639 SemaDiagnosticBuilder noteExplicitConv(
1640 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1641 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1642 << ConvTy->isEnumeralType() << ConvTy;
1645 SemaDiagnosticBuilder diagnoseAmbiguous(
1646 Sema &S, SourceLocation Loc, QualType T) override {
1647 return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T;
1650 SemaDiagnosticBuilder noteAmbiguous(
1651 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1652 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1653 << ConvTy->isEnumeralType() << ConvTy;
1656 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
1658 QualType ConvTy) override {
1660 S.getLangOpts().CPlusPlus11
1661 ? diag::warn_cxx98_compat_array_size_conversion
1662 : diag::ext_array_size_conversion)
1663 << T << ConvTy->isEnumeralType() << ConvTy;
1665 } SizeDiagnoser(ArraySize);
1667 ConvertedSize = PerformContextualImplicitConversion(StartLoc, ArraySize,
1670 if (ConvertedSize.isInvalid())
1673 ArraySize = ConvertedSize.get();
1674 QualType SizeType = ArraySize->getType();
1676 if (!SizeType->isIntegralOrUnscopedEnumerationType())
1679 // C++98 [expr.new]p7:
1680 // The expression in a direct-new-declarator shall have integral type
1681 // with a non-negative value.
1683 // Let's see if this is a constant < 0. If so, we reject it out of
1684 // hand. Otherwise, if it's not a constant, we must have an unparenthesized
1687 // Note: such a construct has well-defined semantics in C++11: it throws
1688 // std::bad_array_new_length.
1689 if (!ArraySize->isValueDependent()) {
1691 // We've already performed any required implicit conversion to integer or
1692 // unscoped enumeration type.
1693 if (ArraySize->isIntegerConstantExpr(Value, Context)) {
1694 if (Value < llvm::APSInt(
1695 llvm::APInt::getNullValue(Value.getBitWidth()),
1696 Value.isUnsigned())) {
1697 if (getLangOpts().CPlusPlus11)
1698 Diag(ArraySize->getLocStart(),
1699 diag::warn_typecheck_negative_array_new_size)
1700 << ArraySize->getSourceRange();
1702 return ExprError(Diag(ArraySize->getLocStart(),
1703 diag::err_typecheck_negative_array_size)
1704 << ArraySize->getSourceRange());
1705 } else if (!AllocType->isDependentType()) {
1706 unsigned ActiveSizeBits =
1707 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value);
1708 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
1709 if (getLangOpts().CPlusPlus11)
1710 Diag(ArraySize->getLocStart(),
1711 diag::warn_array_new_too_large)
1712 << Value.toString(10)
1713 << ArraySize->getSourceRange();
1715 return ExprError(Diag(ArraySize->getLocStart(),
1716 diag::err_array_too_large)
1717 << Value.toString(10)
1718 << ArraySize->getSourceRange());
1721 } else if (TypeIdParens.isValid()) {
1722 // Can't have dynamic array size when the type-id is in parentheses.
1723 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst)
1724 << ArraySize->getSourceRange()
1725 << FixItHint::CreateRemoval(TypeIdParens.getBegin())
1726 << FixItHint::CreateRemoval(TypeIdParens.getEnd());
1728 TypeIdParens = SourceRange();
1732 // Note that we do *not* convert the argument in any way. It can
1733 // be signed, larger than size_t, whatever.
1736 FunctionDecl *OperatorNew = nullptr;
1737 FunctionDecl *OperatorDelete = nullptr;
1739 if (!AllocType->isDependentType() &&
1740 !Expr::hasAnyTypeDependentArguments(PlacementArgs) &&
1741 FindAllocationFunctions(StartLoc,
1742 SourceRange(PlacementLParen, PlacementRParen),
1743 UseGlobal, AllocType, ArraySize, PlacementArgs,
1744 OperatorNew, OperatorDelete))
1747 // If this is an array allocation, compute whether the usual array
1748 // deallocation function for the type has a size_t parameter.
1749 bool UsualArrayDeleteWantsSize = false;
1750 if (ArraySize && !AllocType->isDependentType())
1751 UsualArrayDeleteWantsSize
1752 = doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType);
1754 SmallVector<Expr *, 8> AllPlaceArgs;
1756 const FunctionProtoType *Proto =
1757 OperatorNew->getType()->getAs<FunctionProtoType>();
1758 VariadicCallType CallType = Proto->isVariadic() ? VariadicFunction
1759 : VariadicDoesNotApply;
1761 // We've already converted the placement args, just fill in any default
1762 // arguments. Skip the first parameter because we don't have a corresponding
1764 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, Proto, 1,
1765 PlacementArgs, AllPlaceArgs, CallType))
1768 if (!AllPlaceArgs.empty())
1769 PlacementArgs = AllPlaceArgs;
1771 // FIXME: This is wrong: PlacementArgs misses out the first (size) argument.
1772 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, PlacementArgs);
1774 // FIXME: Missing call to CheckFunctionCall or equivalent
1777 // Warn if the type is over-aligned and is being allocated by global operator
1779 if (PlacementArgs.empty() && OperatorNew &&
1780 (OperatorNew->isImplicit() ||
1781 (OperatorNew->getLocStart().isValid() &&
1782 getSourceManager().isInSystemHeader(OperatorNew->getLocStart())))) {
1783 if (unsigned Align = Context.getPreferredTypeAlign(AllocType.getTypePtr())){
1784 unsigned SuitableAlign = Context.getTargetInfo().getSuitableAlign();
1785 if (Align > SuitableAlign)
1786 Diag(StartLoc, diag::warn_overaligned_type)
1788 << unsigned(Align / Context.getCharWidth())
1789 << unsigned(SuitableAlign / Context.getCharWidth());
1793 QualType InitType = AllocType;
1794 // Array 'new' can't have any initializers except empty parentheses.
1795 // Initializer lists are also allowed, in C++11. Rely on the parser for the
1796 // dialect distinction.
1797 if (ResultType->isArrayType() || ArraySize) {
1798 if (!isLegalArrayNewInitializer(initStyle, Initializer)) {
1799 SourceRange InitRange(Inits[0]->getLocStart(),
1800 Inits[NumInits - 1]->getLocEnd());
1801 Diag(StartLoc, diag::err_new_array_init_args) << InitRange;
1804 if (InitListExpr *ILE = dyn_cast_or_null<InitListExpr>(Initializer)) {
1805 // We do the initialization typechecking against the array type
1806 // corresponding to the number of initializers + 1 (to also check
1807 // default-initialization).
1808 unsigned NumElements = ILE->getNumInits() + 1;
1809 InitType = Context.getConstantArrayType(AllocType,
1810 llvm::APInt(Context.getTypeSize(Context.getSizeType()), NumElements),
1811 ArrayType::Normal, 0);
1815 // If we can perform the initialization, and we've not already done so,
1817 if (!AllocType->isDependentType() &&
1818 !Expr::hasAnyTypeDependentArguments(
1819 llvm::makeArrayRef(Inits, NumInits))) {
1820 // C++11 [expr.new]p15:
1821 // A new-expression that creates an object of type T initializes that
1822 // object as follows:
1823 InitializationKind Kind
1824 // - If the new-initializer is omitted, the object is default-
1825 // initialized (8.5); if no initialization is performed,
1826 // the object has indeterminate value
1827 = initStyle == CXXNewExpr::NoInit
1828 ? InitializationKind::CreateDefault(TypeRange.getBegin())
1829 // - Otherwise, the new-initializer is interpreted according to the
1830 // initialization rules of 8.5 for direct-initialization.
1831 : initStyle == CXXNewExpr::ListInit
1832 ? InitializationKind::CreateDirectList(TypeRange.getBegin())
1833 : InitializationKind::CreateDirect(TypeRange.getBegin(),
1834 DirectInitRange.getBegin(),
1835 DirectInitRange.getEnd());
1837 InitializedEntity Entity
1838 = InitializedEntity::InitializeNew(StartLoc, InitType);
1839 InitializationSequence InitSeq(*this, Entity, Kind, MultiExprArg(Inits, NumInits));
1840 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind,
1841 MultiExprArg(Inits, NumInits));
1842 if (FullInit.isInvalid())
1845 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because
1846 // we don't want the initialized object to be destructed.
1847 if (CXXBindTemporaryExpr *Binder =
1848 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get()))
1849 FullInit = Binder->getSubExpr();
1851 Initializer = FullInit.get();
1854 // Mark the new and delete operators as referenced.
1856 if (DiagnoseUseOfDecl(OperatorNew, StartLoc))
1858 MarkFunctionReferenced(StartLoc, OperatorNew);
1860 if (OperatorDelete) {
1861 if (DiagnoseUseOfDecl(OperatorDelete, StartLoc))
1863 MarkFunctionReferenced(StartLoc, OperatorDelete);
1866 // C++0x [expr.new]p17:
1867 // If the new expression creates an array of objects of class type,
1868 // access and ambiguity control are done for the destructor.
1869 QualType BaseAllocType = Context.getBaseElementType(AllocType);
1870 if (ArraySize && !BaseAllocType->isDependentType()) {
1871 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) {
1872 if (CXXDestructorDecl *dtor = LookupDestructor(
1873 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) {
1874 MarkFunctionReferenced(StartLoc, dtor);
1875 CheckDestructorAccess(StartLoc, dtor,
1876 PDiag(diag::err_access_dtor)
1878 if (DiagnoseUseOfDecl(dtor, StartLoc))
1884 return new (Context)
1885 CXXNewExpr(Context, UseGlobal, OperatorNew, OperatorDelete,
1886 UsualArrayDeleteWantsSize, PlacementArgs, TypeIdParens,
1887 ArraySize, initStyle, Initializer, ResultType, AllocTypeInfo,
1888 Range, DirectInitRange);
1891 /// \brief Checks that a type is suitable as the allocated type
1892 /// in a new-expression.
1893 bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc,
1895 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
1896 // abstract class type or array thereof.
1897 if (AllocType->isFunctionType())
1898 return Diag(Loc, diag::err_bad_new_type)
1899 << AllocType << 0 << R;
1900 else if (AllocType->isReferenceType())
1901 return Diag(Loc, diag::err_bad_new_type)
1902 << AllocType << 1 << R;
1903 else if (!AllocType->isDependentType() &&
1904 RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R))
1906 else if (RequireNonAbstractType(Loc, AllocType,
1907 diag::err_allocation_of_abstract_type))
1909 else if (AllocType->isVariablyModifiedType())
1910 return Diag(Loc, diag::err_variably_modified_new_type)
1912 else if (unsigned AddressSpace = AllocType.getAddressSpace())
1913 return Diag(Loc, diag::err_address_space_qualified_new)
1914 << AllocType.getUnqualifiedType() << AddressSpace;
1915 else if (getLangOpts().ObjCAutoRefCount) {
1916 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) {
1917 QualType BaseAllocType = Context.getBaseElementType(AT);
1918 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None &&
1919 BaseAllocType->isObjCLifetimeType())
1920 return Diag(Loc, diag::err_arc_new_array_without_ownership)
1928 /// \brief Determine whether the given function is a non-placement
1929 /// deallocation function.
1930 static bool isNonPlacementDeallocationFunction(Sema &S, FunctionDecl *FD) {
1931 if (FD->isInvalidDecl())
1934 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD))
1935 return Method->isUsualDeallocationFunction();
1937 if (FD->getOverloadedOperator() != OO_Delete &&
1938 FD->getOverloadedOperator() != OO_Array_Delete)
1941 if (FD->getNumParams() == 1)
1944 return S.getLangOpts().SizedDeallocation && FD->getNumParams() == 2 &&
1945 S.Context.hasSameUnqualifiedType(FD->getParamDecl(1)->getType(),
1946 S.Context.getSizeType());
1949 /// FindAllocationFunctions - Finds the overloads of operator new and delete
1950 /// that are appropriate for the allocation.
1951 bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
1952 bool UseGlobal, QualType AllocType,
1953 bool IsArray, MultiExprArg PlaceArgs,
1954 FunctionDecl *&OperatorNew,
1955 FunctionDecl *&OperatorDelete) {
1956 // --- Choosing an allocation function ---
1957 // C++ 5.3.4p8 - 14 & 18
1958 // 1) If UseGlobal is true, only look in the global scope. Else, also look
1959 // in the scope of the allocated class.
1960 // 2) If an array size is given, look for operator new[], else look for
1962 // 3) The first argument is always size_t. Append the arguments from the
1965 SmallVector<Expr*, 8> AllocArgs(1 + PlaceArgs.size());
1966 // We don't care about the actual value of this argument.
1967 // FIXME: Should the Sema create the expression and embed it in the syntax
1968 // tree? Or should the consumer just recalculate the value?
1969 IntegerLiteral Size(Context, llvm::APInt::getNullValue(
1970 Context.getTargetInfo().getPointerWidth(0)),
1971 Context.getSizeType(),
1973 AllocArgs[0] = &Size;
1974 std::copy(PlaceArgs.begin(), PlaceArgs.end(), AllocArgs.begin() + 1);
1976 // C++ [expr.new]p8:
1977 // If the allocated type is a non-array type, the allocation
1978 // function's name is operator new and the deallocation function's
1979 // name is operator delete. If the allocated type is an array
1980 // type, the allocation function's name is operator new[] and the
1981 // deallocation function's name is operator delete[].
1982 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName(
1983 IsArray ? OO_Array_New : OO_New);
1984 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
1985 IsArray ? OO_Array_Delete : OO_Delete);
1987 QualType AllocElemType = Context.getBaseElementType(AllocType);
1989 if (AllocElemType->isRecordType() && !UseGlobal) {
1990 CXXRecordDecl *Record
1991 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl());
1992 if (FindAllocationOverload(StartLoc, Range, NewName, AllocArgs, Record,
1993 /*AllowMissing=*/true, OperatorNew))
1998 // Didn't find a member overload. Look for a global one.
1999 DeclareGlobalNewDelete();
2000 DeclContext *TUDecl = Context.getTranslationUnitDecl();
2001 bool FallbackEnabled = IsArray && Context.getLangOpts().MSVCCompat;
2002 if (FindAllocationOverload(StartLoc, Range, NewName, AllocArgs, TUDecl,
2003 /*AllowMissing=*/FallbackEnabled, OperatorNew,
2004 /*Diagnose=*/!FallbackEnabled)) {
2005 if (!FallbackEnabled)
2008 // MSVC will fall back on trying to find a matching global operator new
2009 // if operator new[] cannot be found. Also, MSVC will leak by not
2010 // generating a call to operator delete or operator delete[], but we
2011 // will not replicate that bug.
2012 NewName = Context.DeclarationNames.getCXXOperatorName(OO_New);
2013 DeleteName = Context.DeclarationNames.getCXXOperatorName(OO_Delete);
2014 if (FindAllocationOverload(StartLoc, Range, NewName, AllocArgs, TUDecl,
2015 /*AllowMissing=*/false, OperatorNew))
2020 // We don't need an operator delete if we're running under
2022 if (!getLangOpts().Exceptions) {
2023 OperatorDelete = nullptr;
2027 // C++ [expr.new]p19:
2029 // If the new-expression begins with a unary :: operator, the
2030 // deallocation function's name is looked up in the global
2031 // scope. Otherwise, if the allocated type is a class type T or an
2032 // array thereof, the deallocation function's name is looked up in
2033 // the scope of T. If this lookup fails to find the name, or if
2034 // the allocated type is not a class type or array thereof, the
2035 // deallocation function's name is looked up in the global scope.
2036 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName);
2037 if (AllocElemType->isRecordType() && !UseGlobal) {
2039 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl());
2040 LookupQualifiedName(FoundDelete, RD);
2042 if (FoundDelete.isAmbiguous())
2043 return true; // FIXME: clean up expressions?
2045 if (FoundDelete.empty()) {
2046 DeclareGlobalNewDelete();
2047 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2050 FoundDelete.suppressDiagnostics();
2052 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches;
2054 // Whether we're looking for a placement operator delete is dictated
2055 // by whether we selected a placement operator new, not by whether
2056 // we had explicit placement arguments. This matters for things like
2057 // struct A { void *operator new(size_t, int = 0); ... };
2059 bool isPlacementNew = (!PlaceArgs.empty() || OperatorNew->param_size() != 1);
2061 if (isPlacementNew) {
2062 // C++ [expr.new]p20:
2063 // A declaration of a placement deallocation function matches the
2064 // declaration of a placement allocation function if it has the
2065 // same number of parameters and, after parameter transformations
2066 // (8.3.5), all parameter types except the first are
2069 // To perform this comparison, we compute the function type that
2070 // the deallocation function should have, and use that type both
2071 // for template argument deduction and for comparison purposes.
2073 // FIXME: this comparison should ignore CC and the like.
2074 QualType ExpectedFunctionType;
2076 const FunctionProtoType *Proto
2077 = OperatorNew->getType()->getAs<FunctionProtoType>();
2079 SmallVector<QualType, 4> ArgTypes;
2080 ArgTypes.push_back(Context.VoidPtrTy);
2081 for (unsigned I = 1, N = Proto->getNumParams(); I < N; ++I)
2082 ArgTypes.push_back(Proto->getParamType(I));
2084 FunctionProtoType::ExtProtoInfo EPI;
2085 EPI.Variadic = Proto->isVariadic();
2087 ExpectedFunctionType
2088 = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI);
2091 for (LookupResult::iterator D = FoundDelete.begin(),
2092 DEnd = FoundDelete.end();
2094 FunctionDecl *Fn = nullptr;
2095 if (FunctionTemplateDecl *FnTmpl
2096 = dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) {
2097 // Perform template argument deduction to try to match the
2098 // expected function type.
2099 TemplateDeductionInfo Info(StartLoc);
2100 if (DeduceTemplateArguments(FnTmpl, nullptr, ExpectedFunctionType, Fn,
2104 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl());
2106 if (Context.hasSameType(Fn->getType(), ExpectedFunctionType))
2107 Matches.push_back(std::make_pair(D.getPair(), Fn));
2110 // C++ [expr.new]p20:
2111 // [...] Any non-placement deallocation function matches a
2112 // non-placement allocation function. [...]
2113 for (LookupResult::iterator D = FoundDelete.begin(),
2114 DEnd = FoundDelete.end();
2116 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>((*D)->getUnderlyingDecl()))
2117 if (isNonPlacementDeallocationFunction(*this, Fn))
2118 Matches.push_back(std::make_pair(D.getPair(), Fn));
2121 // C++1y [expr.new]p22:
2122 // For a non-placement allocation function, the normal deallocation
2123 // function lookup is used
2124 // C++1y [expr.delete]p?:
2125 // If [...] deallocation function lookup finds both a usual deallocation
2126 // function with only a pointer parameter and a usual deallocation
2127 // function with both a pointer parameter and a size parameter, then the
2128 // selected deallocation function shall be the one with two parameters.
2129 // Otherwise, the selected deallocation function shall be the function
2130 // with one parameter.
2131 if (getLangOpts().SizedDeallocation && Matches.size() == 2) {
2132 if (Matches[0].second->getNumParams() == 1)
2133 Matches.erase(Matches.begin());
2135 Matches.erase(Matches.begin() + 1);
2136 assert(Matches[0].second->getNumParams() == 2 &&
2137 "found an unexpected usual deallocation function");
2141 // C++ [expr.new]p20:
2142 // [...] If the lookup finds a single matching deallocation
2143 // function, that function will be called; otherwise, no
2144 // deallocation function will be called.
2145 if (Matches.size() == 1) {
2146 OperatorDelete = Matches[0].second;
2148 // C++0x [expr.new]p20:
2149 // If the lookup finds the two-parameter form of a usual
2150 // deallocation function (3.7.4.2) and that function, considered
2151 // as a placement deallocation function, would have been
2152 // selected as a match for the allocation function, the program
2154 if (!PlaceArgs.empty() && getLangOpts().CPlusPlus11 &&
2155 isNonPlacementDeallocationFunction(*this, OperatorDelete)) {
2156 Diag(StartLoc, diag::err_placement_new_non_placement_delete)
2157 << SourceRange(PlaceArgs.front()->getLocStart(),
2158 PlaceArgs.back()->getLocEnd());
2159 if (!OperatorDelete->isImplicit())
2160 Diag(OperatorDelete->getLocation(), diag::note_previous_decl)
2163 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(),
2171 /// \brief Find an fitting overload for the allocation function
2172 /// in the specified scope.
2174 /// \param StartLoc The location of the 'new' token.
2175 /// \param Range The range of the placement arguments.
2176 /// \param Name The name of the function ('operator new' or 'operator new[]').
2177 /// \param Args The placement arguments specified.
2178 /// \param Ctx The scope in which we should search; either a class scope or the
2179 /// translation unit.
2180 /// \param AllowMissing If \c true, report an error if we can't find any
2181 /// allocation functions. Otherwise, succeed but don't fill in \p
2183 /// \param Operator Filled in with the found allocation function. Unchanged if
2184 /// no allocation function was found.
2185 /// \param Diagnose If \c true, issue errors if the allocation function is not
2187 bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range,
2188 DeclarationName Name, MultiExprArg Args,
2190 bool AllowMissing, FunctionDecl *&Operator,
2192 LookupResult R(*this, Name, StartLoc, LookupOrdinaryName);
2193 LookupQualifiedName(R, Ctx);
2195 if (AllowMissing || !Diagnose)
2197 return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call)
2201 if (R.isAmbiguous())
2204 R.suppressDiagnostics();
2206 OverloadCandidateSet Candidates(StartLoc, OverloadCandidateSet::CSK_Normal);
2207 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
2208 Alloc != AllocEnd; ++Alloc) {
2209 // Even member operator new/delete are implicitly treated as
2210 // static, so don't use AddMemberCandidate.
2211 NamedDecl *D = (*Alloc)->getUnderlyingDecl();
2213 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
2214 AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(),
2215 /*ExplicitTemplateArgs=*/nullptr,
2217 /*SuppressUserConversions=*/false);
2221 FunctionDecl *Fn = cast<FunctionDecl>(D);
2222 AddOverloadCandidate(Fn, Alloc.getPair(), Args, Candidates,
2223 /*SuppressUserConversions=*/false);
2226 // Do the resolution.
2227 OverloadCandidateSet::iterator Best;
2228 switch (Candidates.BestViableFunction(*this, StartLoc, Best)) {
2231 FunctionDecl *FnDecl = Best->Function;
2232 if (CheckAllocationAccess(StartLoc, Range, R.getNamingClass(),
2233 Best->FoundDecl, Diagnose) == AR_inaccessible)
2240 case OR_No_Viable_Function:
2242 Diag(StartLoc, diag::err_ovl_no_viable_function_in_call)
2244 Candidates.NoteCandidates(*this, OCD_AllCandidates, Args);
2250 Diag(StartLoc, diag::err_ovl_ambiguous_call)
2252 Candidates.NoteCandidates(*this, OCD_ViableCandidates, Args);
2258 Diag(StartLoc, diag::err_ovl_deleted_call)
2259 << Best->Function->isDeleted()
2261 << getDeletedOrUnavailableSuffix(Best->Function)
2263 Candidates.NoteCandidates(*this, OCD_AllCandidates, Args);
2268 llvm_unreachable("Unreachable, bad result from BestViableFunction");
2272 /// DeclareGlobalNewDelete - Declare the global forms of operator new and
2273 /// delete. These are:
2276 /// void* operator new(std::size_t) throw(std::bad_alloc);
2277 /// void* operator new[](std::size_t) throw(std::bad_alloc);
2278 /// void operator delete(void *) throw();
2279 /// void operator delete[](void *) throw();
2281 /// void* operator new(std::size_t);
2282 /// void* operator new[](std::size_t);
2283 /// void operator delete(void *) noexcept;
2284 /// void operator delete[](void *) noexcept;
2286 /// void* operator new(std::size_t);
2287 /// void* operator new[](std::size_t);
2288 /// void operator delete(void *) noexcept;
2289 /// void operator delete[](void *) noexcept;
2290 /// void operator delete(void *, std::size_t) noexcept;
2291 /// void operator delete[](void *, std::size_t) noexcept;
2293 /// Note that the placement and nothrow forms of new are *not* implicitly
2294 /// declared. Their use requires including \<new\>.
2295 void Sema::DeclareGlobalNewDelete() {
2296 if (GlobalNewDeleteDeclared)
2299 // C++ [basic.std.dynamic]p2:
2300 // [...] The following allocation and deallocation functions (18.4) are
2301 // implicitly declared in global scope in each translation unit of a
2305 // void* operator new(std::size_t) throw(std::bad_alloc);
2306 // void* operator new[](std::size_t) throw(std::bad_alloc);
2307 // void operator delete(void*) throw();
2308 // void operator delete[](void*) throw();
2310 // void* operator new(std::size_t);
2311 // void* operator new[](std::size_t);
2312 // void operator delete(void*) noexcept;
2313 // void operator delete[](void*) noexcept;
2315 // void* operator new(std::size_t);
2316 // void* operator new[](std::size_t);
2317 // void operator delete(void*) noexcept;
2318 // void operator delete[](void*) noexcept;
2319 // void operator delete(void*, std::size_t) noexcept;
2320 // void operator delete[](void*, std::size_t) noexcept;
2322 // These implicit declarations introduce only the function names operator
2323 // new, operator new[], operator delete, operator delete[].
2325 // Here, we need to refer to std::bad_alloc, so we will implicitly declare
2326 // "std" or "bad_alloc" as necessary to form the exception specification.
2327 // However, we do not make these implicit declarations visible to name
2329 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) {
2330 // The "std::bad_alloc" class has not yet been declared, so build it
2332 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class,
2333 getOrCreateStdNamespace(),
2334 SourceLocation(), SourceLocation(),
2335 &PP.getIdentifierTable().get("bad_alloc"),
2337 getStdBadAlloc()->setImplicit(true);
2340 GlobalNewDeleteDeclared = true;
2342 QualType VoidPtr = Context.getPointerType(Context.VoidTy);
2343 QualType SizeT = Context.getSizeType();
2345 DeclareGlobalAllocationFunction(
2346 Context.DeclarationNames.getCXXOperatorName(OO_New),
2347 VoidPtr, SizeT, QualType());
2348 DeclareGlobalAllocationFunction(
2349 Context.DeclarationNames.getCXXOperatorName(OO_Array_New),
2350 VoidPtr, SizeT, QualType());
2351 DeclareGlobalAllocationFunction(
2352 Context.DeclarationNames.getCXXOperatorName(OO_Delete),
2353 Context.VoidTy, VoidPtr);
2354 DeclareGlobalAllocationFunction(
2355 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete),
2356 Context.VoidTy, VoidPtr);
2357 if (getLangOpts().SizedDeallocation) {
2358 DeclareGlobalAllocationFunction(
2359 Context.DeclarationNames.getCXXOperatorName(OO_Delete),
2360 Context.VoidTy, VoidPtr, Context.getSizeType());
2361 DeclareGlobalAllocationFunction(
2362 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete),
2363 Context.VoidTy, VoidPtr, Context.getSizeType());
2367 /// DeclareGlobalAllocationFunction - Declares a single implicit global
2368 /// allocation function if it doesn't already exist.
2369 void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
2371 QualType Param1, QualType Param2) {
2372 DeclContext *GlobalCtx = Context.getTranslationUnitDecl();
2373 unsigned NumParams = Param2.isNull() ? 1 : 2;
2375 // Check if this function is already declared.
2376 DeclContext::lookup_result R = GlobalCtx->lookup(Name);
2377 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end();
2378 Alloc != AllocEnd; ++Alloc) {
2379 // Only look at non-template functions, as it is the predefined,
2380 // non-templated allocation function we are trying to declare here.
2381 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
2382 if (Func->getNumParams() == NumParams) {
2383 QualType InitialParam1Type =
2384 Context.getCanonicalType(Func->getParamDecl(0)
2385 ->getType().getUnqualifiedType());
2386 QualType InitialParam2Type =
2388 ? Context.getCanonicalType(Func->getParamDecl(1)
2389 ->getType().getUnqualifiedType())
2391 // FIXME: Do we need to check for default arguments here?
2392 if (InitialParam1Type == Param1 &&
2393 (NumParams == 1 || InitialParam2Type == Param2)) {
2394 // Make the function visible to name lookup, even if we found it in
2395 // an unimported module. It either is an implicitly-declared global
2396 // allocation function, or is suppressing that function.
2397 Func->setHidden(false);
2404 FunctionProtoType::ExtProtoInfo EPI;
2406 QualType BadAllocType;
2407 bool HasBadAllocExceptionSpec
2408 = (Name.getCXXOverloadedOperator() == OO_New ||
2409 Name.getCXXOverloadedOperator() == OO_Array_New);
2410 if (HasBadAllocExceptionSpec) {
2411 if (!getLangOpts().CPlusPlus11) {
2412 BadAllocType = Context.getTypeDeclType(getStdBadAlloc());
2413 assert(StdBadAlloc && "Must have std::bad_alloc declared");
2414 EPI.ExceptionSpec.Type = EST_Dynamic;
2415 EPI.ExceptionSpec.Exceptions = llvm::makeArrayRef(BadAllocType);
2419 getLangOpts().CPlusPlus11 ? EST_BasicNoexcept : EST_DynamicNone;
2422 QualType Params[] = { Param1, Param2 };
2424 QualType FnType = Context.getFunctionType(
2425 Return, llvm::makeArrayRef(Params, NumParams), EPI);
2426 FunctionDecl *Alloc =
2427 FunctionDecl::Create(Context, GlobalCtx, SourceLocation(),
2428 SourceLocation(), Name,
2429 FnType, /*TInfo=*/nullptr, SC_None, false, true);
2430 Alloc->setImplicit();
2432 // Implicit sized deallocation functions always have default visibility.
2433 Alloc->addAttr(VisibilityAttr::CreateImplicit(Context,
2434 VisibilityAttr::Default));
2436 ParmVarDecl *ParamDecls[2];
2437 for (unsigned I = 0; I != NumParams; ++I) {
2438 ParamDecls[I] = ParmVarDecl::Create(Context, Alloc, SourceLocation(),
2439 SourceLocation(), nullptr,
2440 Params[I], /*TInfo=*/nullptr,
2442 ParamDecls[I]->setImplicit();
2444 Alloc->setParams(llvm::makeArrayRef(ParamDecls, NumParams));
2446 Context.getTranslationUnitDecl()->addDecl(Alloc);
2447 IdResolver.tryAddTopLevelDecl(Alloc, Name);
2450 FunctionDecl *Sema::FindUsualDeallocationFunction(SourceLocation StartLoc,
2451 bool CanProvideSize,
2452 DeclarationName Name) {
2453 DeclareGlobalNewDelete();
2455 LookupResult FoundDelete(*this, Name, StartLoc, LookupOrdinaryName);
2456 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2458 // C++ [expr.new]p20:
2459 // [...] Any non-placement deallocation function matches a
2460 // non-placement allocation function. [...]
2461 llvm::SmallVector<FunctionDecl*, 2> Matches;
2462 for (LookupResult::iterator D = FoundDelete.begin(),
2463 DEnd = FoundDelete.end();
2465 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>(*D))
2466 if (isNonPlacementDeallocationFunction(*this, Fn))
2467 Matches.push_back(Fn);
2470 // C++1y [expr.delete]p?:
2471 // If the type is complete and deallocation function lookup finds both a
2472 // usual deallocation function with only a pointer parameter and a usual
2473 // deallocation function with both a pointer parameter and a size
2474 // parameter, then the selected deallocation function shall be the one
2475 // with two parameters. Otherwise, the selected deallocation function
2476 // shall be the function with one parameter.
2477 if (getLangOpts().SizedDeallocation && Matches.size() == 2) {
2478 unsigned NumArgs = CanProvideSize ? 2 : 1;
2479 if (Matches[0]->getNumParams() != NumArgs)
2480 Matches.erase(Matches.begin());
2482 Matches.erase(Matches.begin() + 1);
2483 assert(Matches[0]->getNumParams() == NumArgs &&
2484 "found an unexpected usual deallocation function");
2487 if (getLangOpts().CUDA)
2488 EraseUnwantedCUDAMatches(dyn_cast<FunctionDecl>(CurContext), Matches);
2490 assert(Matches.size() == 1 &&
2491 "unexpectedly have multiple usual deallocation functions");
2492 return Matches.front();
2495 bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
2496 DeclarationName Name,
2497 FunctionDecl* &Operator, bool Diagnose) {
2498 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
2499 // Try to find operator delete/operator delete[] in class scope.
2500 LookupQualifiedName(Found, RD);
2502 if (Found.isAmbiguous())
2505 Found.suppressDiagnostics();
2507 SmallVector<DeclAccessPair,4> Matches;
2508 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end();
2510 NamedDecl *ND = (*F)->getUnderlyingDecl();
2512 // Ignore template operator delete members from the check for a usual
2513 // deallocation function.
2514 if (isa<FunctionTemplateDecl>(ND))
2517 if (cast<CXXMethodDecl>(ND)->isUsualDeallocationFunction())
2518 Matches.push_back(F.getPair());
2521 if (getLangOpts().CUDA)
2522 EraseUnwantedCUDAMatches(dyn_cast<FunctionDecl>(CurContext), Matches);
2524 // There's exactly one suitable operator; pick it.
2525 if (Matches.size() == 1) {
2526 Operator = cast<CXXMethodDecl>(Matches[0]->getUnderlyingDecl());
2528 if (Operator->isDeleted()) {
2530 Diag(StartLoc, diag::err_deleted_function_use);
2531 NoteDeletedFunction(Operator);
2536 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(),
2537 Matches[0], Diagnose) == AR_inaccessible)
2542 // We found multiple suitable operators; complain about the ambiguity.
2543 } else if (!Matches.empty()) {
2545 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found)
2548 for (SmallVectorImpl<DeclAccessPair>::iterator
2549 F = Matches.begin(), FEnd = Matches.end(); F != FEnd; ++F)
2550 Diag((*F)->getUnderlyingDecl()->getLocation(),
2551 diag::note_member_declared_here) << Name;
2556 // We did find operator delete/operator delete[] declarations, but
2557 // none of them were suitable.
2558 if (!Found.empty()) {
2560 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found)
2563 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end();
2565 Diag((*F)->getUnderlyingDecl()->getLocation(),
2566 diag::note_member_declared_here) << Name;
2576 /// \brief Checks whether delete-expression, and new-expression used for
2577 /// initializing deletee have the same array form.
2578 class MismatchingNewDeleteDetector {
2580 enum MismatchResult {
2581 /// Indicates that there is no mismatch or a mismatch cannot be proven.
2583 /// Indicates that variable is initialized with mismatching form of \a new.
2585 /// Indicates that member is initialized with mismatching form of \a new.
2586 MemberInitMismatches,
2587 /// Indicates that 1 or more constructors' definitions could not been
2588 /// analyzed, and they will be checked again at the end of translation unit.
2592 /// \param EndOfTU True, if this is the final analysis at the end of
2593 /// translation unit. False, if this is the initial analysis at the point
2594 /// delete-expression was encountered.
2595 explicit MismatchingNewDeleteDetector(bool EndOfTU)
2596 : IsArrayForm(false), Field(nullptr), EndOfTU(EndOfTU),
2597 HasUndefinedConstructors(false) {}
2599 /// \brief Checks whether pointee of a delete-expression is initialized with
2600 /// matching form of new-expression.
2602 /// If return value is \c VarInitMismatches or \c MemberInitMismatches at the
2603 /// point where delete-expression is encountered, then a warning will be
2604 /// issued immediately. If return value is \c AnalyzeLater at the point where
2605 /// delete-expression is seen, then member will be analyzed at the end of
2606 /// translation unit. \c AnalyzeLater is returned iff at least one constructor
2607 /// couldn't be analyzed. If at least one constructor initializes the member
2608 /// with matching type of new, the return value is \c NoMismatch.
2609 MismatchResult analyzeDeleteExpr(const CXXDeleteExpr *DE);
2610 /// \brief Analyzes a class member.
2611 /// \param Field Class member to analyze.
2612 /// \param DeleteWasArrayForm Array form-ness of the delete-expression used
2613 /// for deleting the \p Field.
2614 MismatchResult analyzeField(FieldDecl *Field, bool DeleteWasArrayForm);
2615 /// List of mismatching new-expressions used for initialization of the pointee
2616 llvm::SmallVector<const CXXNewExpr *, 4> NewExprs;
2617 /// Indicates whether delete-expression was in array form.
2623 /// \brief Indicates that there is at least one constructor without body.
2624 bool HasUndefinedConstructors;
2625 /// \brief Returns \c CXXNewExpr from given initialization expression.
2626 /// \param E Expression used for initializing pointee in delete-expression.
2627 /// E can be a single-element \c InitListExpr consisting of new-expression.
2628 const CXXNewExpr *getNewExprFromInitListOrExpr(const Expr *E);
2629 /// \brief Returns whether member is initialized with mismatching form of
2630 /// \c new either by the member initializer or in-class initialization.
2632 /// If bodies of all constructors are not visible at the end of translation
2633 /// unit or at least one constructor initializes member with the matching
2634 /// form of \c new, mismatch cannot be proven, and this function will return
2636 MismatchResult analyzeMemberExpr(const MemberExpr *ME);
2637 /// \brief Returns whether variable is initialized with mismatching form of
2640 /// If variable is initialized with matching form of \c new or variable is not
2641 /// initialized with a \c new expression, this function will return true.
2642 /// If variable is initialized with mismatching form of \c new, returns false.
2643 /// \param D Variable to analyze.
2644 bool hasMatchingVarInit(const DeclRefExpr *D);
2645 /// \brief Checks whether the constructor initializes pointee with mismatching
2648 /// Returns true, if member is initialized with matching form of \c new in
2649 /// member initializer list. Returns false, if member is initialized with the
2650 /// matching form of \c new in this constructor's initializer or given
2651 /// constructor isn't defined at the point where delete-expression is seen, or
2652 /// member isn't initialized by the constructor.
2653 bool hasMatchingNewInCtor(const CXXConstructorDecl *CD);
2654 /// \brief Checks whether member is initialized with matching form of
2655 /// \c new in member initializer list.
2656 bool hasMatchingNewInCtorInit(const CXXCtorInitializer *CI);
2657 /// Checks whether member is initialized with mismatching form of \c new by
2658 /// in-class initializer.
2659 MismatchResult analyzeInClassInitializer();
2663 MismatchingNewDeleteDetector::MismatchResult
2664 MismatchingNewDeleteDetector::analyzeDeleteExpr(const CXXDeleteExpr *DE) {
2666 assert(DE && "Expected delete-expression");
2667 IsArrayForm = DE->isArrayForm();
2668 const Expr *E = DE->getArgument()->IgnoreParenImpCasts();
2669 if (const MemberExpr *ME = dyn_cast<const MemberExpr>(E)) {
2670 return analyzeMemberExpr(ME);
2671 } else if (const DeclRefExpr *D = dyn_cast<const DeclRefExpr>(E)) {
2672 if (!hasMatchingVarInit(D))
2673 return VarInitMismatches;
2679 MismatchingNewDeleteDetector::getNewExprFromInitListOrExpr(const Expr *E) {
2680 assert(E != nullptr && "Expected a valid initializer expression");
2681 E = E->IgnoreParenImpCasts();
2682 if (const InitListExpr *ILE = dyn_cast<const InitListExpr>(E)) {
2683 if (ILE->getNumInits() == 1)
2684 E = dyn_cast<const CXXNewExpr>(ILE->getInit(0)->IgnoreParenImpCasts());
2687 return dyn_cast_or_null<const CXXNewExpr>(E);
2690 bool MismatchingNewDeleteDetector::hasMatchingNewInCtorInit(
2691 const CXXCtorInitializer *CI) {
2692 const CXXNewExpr *NE = nullptr;
2693 if (Field == CI->getMember() &&
2694 (NE = getNewExprFromInitListOrExpr(CI->getInit()))) {
2695 if (NE->isArray() == IsArrayForm)
2698 NewExprs.push_back(NE);
2703 bool MismatchingNewDeleteDetector::hasMatchingNewInCtor(
2704 const CXXConstructorDecl *CD) {
2705 if (CD->isImplicit())
2707 const FunctionDecl *Definition = CD;
2708 if (!CD->isThisDeclarationADefinition() && !CD->isDefined(Definition)) {
2709 HasUndefinedConstructors = true;
2712 for (const auto *CI : cast<const CXXConstructorDecl>(Definition)->inits()) {
2713 if (hasMatchingNewInCtorInit(CI))
2719 MismatchingNewDeleteDetector::MismatchResult
2720 MismatchingNewDeleteDetector::analyzeInClassInitializer() {
2721 assert(Field != nullptr && "This should be called only for members");
2722 const Expr *InitExpr = Field->getInClassInitializer();
2724 return EndOfTU ? NoMismatch : AnalyzeLater;
2725 if (const CXXNewExpr *NE = getNewExprFromInitListOrExpr(InitExpr)) {
2726 if (NE->isArray() != IsArrayForm) {
2727 NewExprs.push_back(NE);
2728 return MemberInitMismatches;
2734 MismatchingNewDeleteDetector::MismatchResult
2735 MismatchingNewDeleteDetector::analyzeField(FieldDecl *Field,
2736 bool DeleteWasArrayForm) {
2737 assert(Field != nullptr && "Analysis requires a valid class member.");
2738 this->Field = Field;
2739 IsArrayForm = DeleteWasArrayForm;
2740 const CXXRecordDecl *RD = cast<const CXXRecordDecl>(Field->getParent());
2741 for (const auto *CD : RD->ctors()) {
2742 if (hasMatchingNewInCtor(CD))
2745 if (HasUndefinedConstructors)
2746 return EndOfTU ? NoMismatch : AnalyzeLater;
2747 if (!NewExprs.empty())
2748 return MemberInitMismatches;
2749 return Field->hasInClassInitializer() ? analyzeInClassInitializer()
2753 MismatchingNewDeleteDetector::MismatchResult
2754 MismatchingNewDeleteDetector::analyzeMemberExpr(const MemberExpr *ME) {
2755 assert(ME != nullptr && "Expected a member expression");
2756 if (FieldDecl *F = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2757 return analyzeField(F, IsArrayForm);
2761 bool MismatchingNewDeleteDetector::hasMatchingVarInit(const DeclRefExpr *D) {
2762 const CXXNewExpr *NE = nullptr;
2763 if (const VarDecl *VD = dyn_cast<const VarDecl>(D->getDecl())) {
2764 if (VD->hasInit() && (NE = getNewExprFromInitListOrExpr(VD->getInit())) &&
2765 NE->isArray() != IsArrayForm) {
2766 NewExprs.push_back(NE);
2769 return NewExprs.empty();
2773 DiagnoseMismatchedNewDelete(Sema &SemaRef, SourceLocation DeleteLoc,
2774 const MismatchingNewDeleteDetector &Detector) {
2775 SourceLocation EndOfDelete = SemaRef.getLocForEndOfToken(DeleteLoc);
2777 if (!Detector.IsArrayForm)
2778 H = FixItHint::CreateInsertion(EndOfDelete, "[]");
2780 SourceLocation RSquare = Lexer::findLocationAfterToken(
2781 DeleteLoc, tok::l_square, SemaRef.getSourceManager(),
2782 SemaRef.getLangOpts(), true);
2783 if (RSquare.isValid())
2784 H = FixItHint::CreateRemoval(SourceRange(EndOfDelete, RSquare));
2786 SemaRef.Diag(DeleteLoc, diag::warn_mismatched_delete_new)
2787 << Detector.IsArrayForm << H;
2789 for (const auto *NE : Detector.NewExprs)
2790 SemaRef.Diag(NE->getExprLoc(), diag::note_allocated_here)
2791 << Detector.IsArrayForm;
2794 void Sema::AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE) {
2795 if (Diags.isIgnored(diag::warn_mismatched_delete_new, SourceLocation()))
2797 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/false);
2798 switch (Detector.analyzeDeleteExpr(DE)) {
2799 case MismatchingNewDeleteDetector::VarInitMismatches:
2800 case MismatchingNewDeleteDetector::MemberInitMismatches: {
2801 DiagnoseMismatchedNewDelete(*this, DE->getLocStart(), Detector);
2804 case MismatchingNewDeleteDetector::AnalyzeLater: {
2805 DeleteExprs[Detector.Field].push_back(
2806 std::make_pair(DE->getLocStart(), DE->isArrayForm()));
2809 case MismatchingNewDeleteDetector::NoMismatch:
2814 void Sema::AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
2815 bool DeleteWasArrayForm) {
2816 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/true);
2817 switch (Detector.analyzeField(Field, DeleteWasArrayForm)) {
2818 case MismatchingNewDeleteDetector::VarInitMismatches:
2819 llvm_unreachable("This analysis should have been done for class members.");
2820 case MismatchingNewDeleteDetector::AnalyzeLater:
2821 llvm_unreachable("Analysis cannot be postponed any point beyond end of "
2822 "translation unit.");
2823 case MismatchingNewDeleteDetector::MemberInitMismatches:
2824 DiagnoseMismatchedNewDelete(*this, DeleteLoc, Detector);
2826 case MismatchingNewDeleteDetector::NoMismatch:
2831 /// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in:
2832 /// @code ::delete ptr; @endcode
2834 /// @code delete [] ptr; @endcode
2836 Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
2837 bool ArrayForm, Expr *ExE) {
2838 // C++ [expr.delete]p1:
2839 // The operand shall have a pointer type, or a class type having a single
2840 // non-explicit conversion function to a pointer type. The result has type
2843 // DR599 amends "pointer type" to "pointer to object type" in both cases.
2845 ExprResult Ex = ExE;
2846 FunctionDecl *OperatorDelete = nullptr;
2847 bool ArrayFormAsWritten = ArrayForm;
2848 bool UsualArrayDeleteWantsSize = false;
2850 if (!Ex.get()->isTypeDependent()) {
2851 // Perform lvalue-to-rvalue cast, if needed.
2852 Ex = DefaultLvalueConversion(Ex.get());
2856 QualType Type = Ex.get()->getType();
2858 class DeleteConverter : public ContextualImplicitConverter {
2860 DeleteConverter() : ContextualImplicitConverter(false, true) {}
2862 bool match(QualType ConvType) override {
2863 // FIXME: If we have an operator T* and an operator void*, we must pick
2865 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
2866 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType())
2871 SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
2872 QualType T) override {
2873 return S.Diag(Loc, diag::err_delete_operand) << T;
2876 SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
2877 QualType T) override {
2878 return S.Diag(Loc, diag::err_delete_incomplete_class_type) << T;
2881 SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
2883 QualType ConvTy) override {
2884 return S.Diag(Loc, diag::err_delete_explicit_conversion) << T << ConvTy;
2887 SemaDiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
2888 QualType ConvTy) override {
2889 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
2893 SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
2894 QualType T) override {
2895 return S.Diag(Loc, diag::err_ambiguous_delete_operand) << T;
2898 SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
2899 QualType ConvTy) override {
2900 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
2904 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
2906 QualType ConvTy) override {
2907 llvm_unreachable("conversion functions are permitted");
2911 Ex = PerformContextualImplicitConversion(StartLoc, Ex.get(), Converter);
2914 Type = Ex.get()->getType();
2915 if (!Converter.match(Type))
2916 // FIXME: PerformContextualImplicitConversion should return ExprError
2917 // itself in this case.
2920 QualType Pointee = Type->getAs<PointerType>()->getPointeeType();
2921 QualType PointeeElem = Context.getBaseElementType(Pointee);
2923 if (unsigned AddressSpace = Pointee.getAddressSpace())
2924 return Diag(Ex.get()->getLocStart(),
2925 diag::err_address_space_qualified_delete)
2926 << Pointee.getUnqualifiedType() << AddressSpace;
2928 CXXRecordDecl *PointeeRD = nullptr;
2929 if (Pointee->isVoidType() && !isSFINAEContext()) {
2930 // The C++ standard bans deleting a pointer to a non-object type, which
2931 // effectively bans deletion of "void*". However, most compilers support
2932 // this, so we treat it as a warning unless we're in a SFINAE context.
2933 Diag(StartLoc, diag::ext_delete_void_ptr_operand)
2934 << Type << Ex.get()->getSourceRange();
2935 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) {
2936 return ExprError(Diag(StartLoc, diag::err_delete_operand)
2937 << Type << Ex.get()->getSourceRange());
2938 } else if (!Pointee->isDependentType()) {
2939 // FIXME: This can result in errors if the definition was imported from a
2940 // module but is hidden.
2941 if (!RequireCompleteType(StartLoc, Pointee,
2942 diag::warn_delete_incomplete, Ex.get())) {
2943 if (const RecordType *RT = PointeeElem->getAs<RecordType>())
2944 PointeeRD = cast<CXXRecordDecl>(RT->getDecl());
2948 if (Pointee->isArrayType() && !ArrayForm) {
2949 Diag(StartLoc, diag::warn_delete_array_type)
2950 << Type << Ex.get()->getSourceRange()
2951 << FixItHint::CreateInsertion(getLocForEndOfToken(StartLoc), "[]");
2955 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
2956 ArrayForm ? OO_Array_Delete : OO_Delete);
2960 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName,
2964 // If we're allocating an array of records, check whether the
2965 // usual operator delete[] has a size_t parameter.
2967 // If the user specifically asked to use the global allocator,
2968 // we'll need to do the lookup into the class.
2970 UsualArrayDeleteWantsSize =
2971 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem);
2973 // Otherwise, the usual operator delete[] should be the
2974 // function we just found.
2975 else if (OperatorDelete && isa<CXXMethodDecl>(OperatorDelete))
2976 UsualArrayDeleteWantsSize = (OperatorDelete->getNumParams() == 2);
2979 if (!PointeeRD->hasIrrelevantDestructor())
2980 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
2981 MarkFunctionReferenced(StartLoc,
2982 const_cast<CXXDestructorDecl*>(Dtor));
2983 if (DiagnoseUseOfDecl(Dtor, StartLoc))
2987 CheckVirtualDtorCall(PointeeRD->getDestructor(), StartLoc,
2988 /*IsDelete=*/true, /*CallCanBeVirtual=*/true,
2989 /*WarnOnNonAbstractTypes=*/!ArrayForm,
2993 if (!OperatorDelete)
2994 // Look for a global declaration.
2995 OperatorDelete = FindUsualDeallocationFunction(
2996 StartLoc, isCompleteType(StartLoc, Pointee) &&
2997 (!ArrayForm || UsualArrayDeleteWantsSize ||
2998 Pointee.isDestructedType()),
3001 MarkFunctionReferenced(StartLoc, OperatorDelete);
3003 // Check access and ambiguity of operator delete and destructor.
3005 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
3006 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor,
3007 PDiag(diag::err_access_dtor) << PointeeElem);
3012 CXXDeleteExpr *Result = new (Context) CXXDeleteExpr(
3013 Context.VoidTy, UseGlobal, ArrayForm, ArrayFormAsWritten,
3014 UsualArrayDeleteWantsSize, OperatorDelete, Ex.get(), StartLoc);
3015 AnalyzeDeleteExprMismatch(Result);
3019 void Sema::CheckVirtualDtorCall(CXXDestructorDecl *dtor, SourceLocation Loc,
3020 bool IsDelete, bool CallCanBeVirtual,
3021 bool WarnOnNonAbstractTypes,
3022 SourceLocation DtorLoc) {
3023 if (!dtor || dtor->isVirtual() || !CallCanBeVirtual)
3026 // C++ [expr.delete]p3:
3027 // In the first alternative (delete object), if the static type of the
3028 // object to be deleted is different from its dynamic type, the static
3029 // type shall be a base class of the dynamic type of the object to be
3030 // deleted and the static type shall have a virtual destructor or the
3031 // behavior is undefined.
3033 const CXXRecordDecl *PointeeRD = dtor->getParent();
3034 // Note: a final class cannot be derived from, no issue there
3035 if (!PointeeRD->isPolymorphic() || PointeeRD->hasAttr<FinalAttr>())
3038 QualType ClassType = dtor->getThisType(Context)->getPointeeType();
3039 if (PointeeRD->isAbstract()) {
3040 // If the class is abstract, we warn by default, because we're
3041 // sure the code has undefined behavior.
3042 Diag(Loc, diag::warn_delete_abstract_non_virtual_dtor) << (IsDelete ? 0 : 1)
3044 } else if (WarnOnNonAbstractTypes) {
3045 // Otherwise, if this is not an array delete, it's a bit suspect,
3046 // but not necessarily wrong.
3047 Diag(Loc, diag::warn_delete_non_virtual_dtor) << (IsDelete ? 0 : 1)
3051 std::string TypeStr;
3052 ClassType.getAsStringInternal(TypeStr, getPrintingPolicy());
3053 Diag(DtorLoc, diag::note_delete_non_virtual)
3054 << FixItHint::CreateInsertion(DtorLoc, TypeStr + "::");
3058 Sema::ConditionResult Sema::ActOnConditionVariable(Decl *ConditionVar,
3059 SourceLocation StmtLoc,
3062 CheckConditionVariable(cast<VarDecl>(ConditionVar), StmtLoc, CK);
3064 return ConditionError();
3065 return ConditionResult(*this, ConditionVar, MakeFullExpr(E.get(), StmtLoc),
3066 CK == ConditionKind::ConstexprIf);
3069 /// \brief Check the use of the given variable as a C++ condition in an if,
3070 /// while, do-while, or switch statement.
3071 ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar,
3072 SourceLocation StmtLoc,
3074 if (ConditionVar->isInvalidDecl())
3077 QualType T = ConditionVar->getType();
3079 // C++ [stmt.select]p2:
3080 // The declarator shall not specify a function or an array.
3081 if (T->isFunctionType())
3082 return ExprError(Diag(ConditionVar->getLocation(),
3083 diag::err_invalid_use_of_function_type)
3084 << ConditionVar->getSourceRange());
3085 else if (T->isArrayType())
3086 return ExprError(Diag(ConditionVar->getLocation(),
3087 diag::err_invalid_use_of_array_type)
3088 << ConditionVar->getSourceRange());
3090 ExprResult Condition = DeclRefExpr::Create(
3091 Context, NestedNameSpecifierLoc(), SourceLocation(), ConditionVar,
3092 /*enclosing*/ false, ConditionVar->getLocation(),
3093 ConditionVar->getType().getNonReferenceType(), VK_LValue);
3095 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get()));
3098 case ConditionKind::Boolean:
3099 return CheckBooleanCondition(StmtLoc, Condition.get());
3101 case ConditionKind::ConstexprIf:
3102 return CheckBooleanCondition(StmtLoc, Condition.get(), true);
3104 case ConditionKind::Switch:
3105 return CheckSwitchCondition(StmtLoc, Condition.get());
3108 llvm_unreachable("unexpected condition kind");
3111 /// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
3112 ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr, bool IsConstexpr) {
3114 // The value of a condition that is an initialized declaration in a statement
3115 // other than a switch statement is the value of the declared variable
3116 // implicitly converted to type bool. If that conversion is ill-formed, the
3117 // program is ill-formed.
3118 // The value of a condition that is an expression is the value of the
3119 // expression, implicitly converted to bool.
3121 // FIXME: Return this value to the caller so they don't need to recompute it.
3122 llvm::APSInt Value(/*BitWidth*/1);
3123 return (IsConstexpr && !CondExpr->isValueDependent())
3124 ? CheckConvertedConstantExpression(CondExpr, Context.BoolTy, Value,
3126 : PerformContextuallyConvertToBool(CondExpr);
3129 /// Helper function to determine whether this is the (deprecated) C++
3130 /// conversion from a string literal to a pointer to non-const char or
3131 /// non-const wchar_t (for narrow and wide string literals,
3134 Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) {
3135 // Look inside the implicit cast, if it exists.
3136 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From))
3137 From = Cast->getSubExpr();
3139 // A string literal (2.13.4) that is not a wide string literal can
3140 // be converted to an rvalue of type "pointer to char"; a wide
3141 // string literal can be converted to an rvalue of type "pointer
3142 // to wchar_t" (C++ 4.2p2).
3143 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens()))
3144 if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
3145 if (const BuiltinType *ToPointeeType
3146 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
3147 // This conversion is considered only when there is an
3148 // explicit appropriate pointer target type (C++ 4.2p2).
3149 if (!ToPtrType->getPointeeType().hasQualifiers()) {
3150 switch (StrLit->getKind()) {
3151 case StringLiteral::UTF8:
3152 case StringLiteral::UTF16:
3153 case StringLiteral::UTF32:
3154 // We don't allow UTF literals to be implicitly converted
3156 case StringLiteral::Ascii:
3157 return (ToPointeeType->getKind() == BuiltinType::Char_U ||
3158 ToPointeeType->getKind() == BuiltinType::Char_S);
3159 case StringLiteral::Wide:
3160 return Context.typesAreCompatible(Context.getWideCharType(),
3161 QualType(ToPointeeType, 0));
3169 static ExprResult BuildCXXCastArgument(Sema &S,
3170 SourceLocation CastLoc,
3173 CXXMethodDecl *Method,
3174 DeclAccessPair FoundDecl,
3175 bool HadMultipleCandidates,
3178 default: llvm_unreachable("Unhandled cast kind!");
3179 case CK_ConstructorConversion: {
3180 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method);
3181 SmallVector<Expr*, 8> ConstructorArgs;
3183 if (S.RequireNonAbstractType(CastLoc, Ty,
3184 diag::err_allocation_of_abstract_type))
3187 if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs))
3190 S.CheckConstructorAccess(CastLoc, Constructor, FoundDecl,
3191 InitializedEntity::InitializeTemporary(Ty));
3192 if (S.DiagnoseUseOfDecl(Method, CastLoc))
3195 ExprResult Result = S.BuildCXXConstructExpr(
3196 CastLoc, Ty, FoundDecl, cast<CXXConstructorDecl>(Method),
3197 ConstructorArgs, HadMultipleCandidates,
3198 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3199 CXXConstructExpr::CK_Complete, SourceRange());
3200 if (Result.isInvalid())
3203 return S.MaybeBindToTemporary(Result.getAs<Expr>());
3206 case CK_UserDefinedConversion: {
3207 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
3209 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ nullptr, FoundDecl);
3210 if (S.DiagnoseUseOfDecl(Method, CastLoc))
3213 // Create an implicit call expr that calls it.
3214 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method);
3215 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv,
3216 HadMultipleCandidates);
3217 if (Result.isInvalid())
3219 // Record usage of conversion in an implicit cast.
3220 Result = ImplicitCastExpr::Create(S.Context, Result.get()->getType(),
3221 CK_UserDefinedConversion, Result.get(),
3222 nullptr, Result.get()->getValueKind());
3224 return S.MaybeBindToTemporary(Result.get());
3229 /// PerformImplicitConversion - Perform an implicit conversion of the
3230 /// expression From to the type ToType using the pre-computed implicit
3231 /// conversion sequence ICS. Returns the converted
3232 /// expression. Action is the kind of conversion we're performing,
3233 /// used in the error message.
3235 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
3236 const ImplicitConversionSequence &ICS,
3237 AssignmentAction Action,
3238 CheckedConversionKind CCK) {
3239 switch (ICS.getKind()) {
3240 case ImplicitConversionSequence::StandardConversion: {
3241 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard,
3243 if (Res.isInvalid())
3249 case ImplicitConversionSequence::UserDefinedConversion: {
3251 FunctionDecl *FD = ICS.UserDefined.ConversionFunction;
3253 QualType BeforeToType;
3254 assert(FD && "no conversion function for user-defined conversion seq");
3255 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) {
3256 CastKind = CK_UserDefinedConversion;
3258 // If the user-defined conversion is specified by a conversion function,
3259 // the initial standard conversion sequence converts the source type to
3260 // the implicit object parameter of the conversion function.
3261 BeforeToType = Context.getTagDeclType(Conv->getParent());
3263 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD);
3264 CastKind = CK_ConstructorConversion;
3265 // Do no conversion if dealing with ... for the first conversion.
3266 if (!ICS.UserDefined.EllipsisConversion) {
3267 // If the user-defined conversion is specified by a constructor, the
3268 // initial standard conversion sequence converts the source type to
3269 // the type required by the argument of the constructor
3270 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType();
3273 // Watch out for ellipsis conversion.
3274 if (!ICS.UserDefined.EllipsisConversion) {
3276 PerformImplicitConversion(From, BeforeToType,
3277 ICS.UserDefined.Before, AA_Converting,
3279 if (Res.isInvalid())
3285 = BuildCXXCastArgument(*this,
3286 From->getLocStart(),
3287 ToType.getNonReferenceType(),
3288 CastKind, cast<CXXMethodDecl>(FD),
3289 ICS.UserDefined.FoundConversionFunction,
3290 ICS.UserDefined.HadMultipleCandidates,
3293 if (CastArg.isInvalid())
3296 From = CastArg.get();
3298 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
3299 AA_Converting, CCK);
3302 case ImplicitConversionSequence::AmbiguousConversion:
3303 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(),
3304 PDiag(diag::err_typecheck_ambiguous_condition)
3305 << From->getSourceRange());
3308 case ImplicitConversionSequence::EllipsisConversion:
3309 llvm_unreachable("Cannot perform an ellipsis conversion");
3311 case ImplicitConversionSequence::BadConversion:
3315 // Everything went well.
3319 /// PerformImplicitConversion - Perform an implicit conversion of the
3320 /// expression From to the type ToType by following the standard
3321 /// conversion sequence SCS. Returns the converted
3322 /// expression. Flavor is the context in which we're performing this
3323 /// conversion, for use in error messages.
3325 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
3326 const StandardConversionSequence& SCS,
3327 AssignmentAction Action,
3328 CheckedConversionKind CCK) {
3329 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast);
3331 // Overall FIXME: we are recomputing too many types here and doing far too
3332 // much extra work. What this means is that we need to keep track of more
3333 // information that is computed when we try the implicit conversion initially,
3334 // so that we don't need to recompute anything here.
3335 QualType FromType = From->getType();
3337 if (SCS.CopyConstructor) {
3338 // FIXME: When can ToType be a reference type?
3339 assert(!ToType->isReferenceType());
3340 if (SCS.Second == ICK_Derived_To_Base) {
3341 SmallVector<Expr*, 8> ConstructorArgs;
3342 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor),
3343 From, /*FIXME:ConstructLoc*/SourceLocation(),
3346 return BuildCXXConstructExpr(
3347 /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
3348 SCS.FoundCopyConstructor, SCS.CopyConstructor,
3349 ConstructorArgs, /*HadMultipleCandidates*/ false,
3350 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3351 CXXConstructExpr::CK_Complete, SourceRange());
3353 return BuildCXXConstructExpr(
3354 /*FIXME:ConstructLoc*/ SourceLocation(), ToType,
3355 SCS.FoundCopyConstructor, SCS.CopyConstructor,
3356 From, /*HadMultipleCandidates*/ false,
3357 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3358 CXXConstructExpr::CK_Complete, SourceRange());
3361 // Resolve overloaded function references.
3362 if (Context.hasSameType(FromType, Context.OverloadTy)) {
3363 DeclAccessPair Found;
3364 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType,
3369 if (DiagnoseUseOfDecl(Fn, From->getLocStart()))
3372 From = FixOverloadedFunctionReference(From, Found, Fn);
3373 FromType = From->getType();
3376 // If we're converting to an atomic type, first convert to the corresponding
3378 QualType ToAtomicType;
3379 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) {
3380 ToAtomicType = ToType;
3381 ToType = ToAtomic->getValueType();
3384 QualType InitialFromType = FromType;
3385 // Perform the first implicit conversion.
3386 switch (SCS.First) {
3388 if (const AtomicType *FromAtomic = FromType->getAs<AtomicType>()) {
3389 FromType = FromAtomic->getValueType().getUnqualifiedType();
3390 From = ImplicitCastExpr::Create(Context, FromType, CK_AtomicToNonAtomic,
3391 From, /*BasePath=*/nullptr, VK_RValue);
3395 case ICK_Lvalue_To_Rvalue: {
3396 assert(From->getObjectKind() != OK_ObjCProperty);
3397 ExprResult FromRes = DefaultLvalueConversion(From);
3398 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!");
3399 From = FromRes.get();
3400 FromType = From->getType();
3404 case ICK_Array_To_Pointer:
3405 FromType = Context.getArrayDecayedType(FromType);
3406 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay,
3407 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3410 case ICK_Function_To_Pointer:
3411 FromType = Context.getPointerType(FromType);
3412 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay,
3413 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3417 llvm_unreachable("Improper first standard conversion");
3420 // Perform the second implicit conversion
3421 switch (SCS.Second) {
3423 // C++ [except.spec]p5:
3424 // [For] assignment to and initialization of pointers to functions,
3425 // pointers to member functions, and references to functions: the
3426 // target entity shall allow at least the exceptions allowed by the
3427 // source value in the assignment or initialization.
3430 case AA_Initializing:
3431 // Note, function argument passing and returning are initialization.
3435 case AA_Passing_CFAudited:
3436 if (CheckExceptionSpecCompatibility(From, ToType))
3442 // Casts and implicit conversions are not initialization, so are not
3443 // checked for exception specification mismatches.
3446 // Nothing else to do.
3449 case ICK_NoReturn_Adjustment:
3450 // If both sides are functions (or pointers/references to them), there could
3451 // be incompatible exception declarations.
3452 if (CheckExceptionSpecCompatibility(From, ToType))
3455 From = ImpCastExprToType(From, ToType, CK_NoOp,
3456 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3459 case ICK_Integral_Promotion:
3460 case ICK_Integral_Conversion:
3461 if (ToType->isBooleanType()) {
3462 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() &&
3463 SCS.Second == ICK_Integral_Promotion &&
3464 "only enums with fixed underlying type can promote to bool");
3465 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean,
3466 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3468 From = ImpCastExprToType(From, ToType, CK_IntegralCast,
3469 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3473 case ICK_Floating_Promotion:
3474 case ICK_Floating_Conversion:
3475 From = ImpCastExprToType(From, ToType, CK_FloatingCast,
3476 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3479 case ICK_Complex_Promotion:
3480 case ICK_Complex_Conversion: {
3481 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType();
3482 QualType ToEl = ToType->getAs<ComplexType>()->getElementType();
3484 if (FromEl->isRealFloatingType()) {
3485 if (ToEl->isRealFloatingType())
3486 CK = CK_FloatingComplexCast;
3488 CK = CK_FloatingComplexToIntegralComplex;
3489 } else if (ToEl->isRealFloatingType()) {
3490 CK = CK_IntegralComplexToFloatingComplex;
3492 CK = CK_IntegralComplexCast;
3494 From = ImpCastExprToType(From, ToType, CK,
3495 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3499 case ICK_Floating_Integral:
3500 if (ToType->isRealFloatingType())
3501 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating,
3502 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3504 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral,
3505 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3508 case ICK_Compatible_Conversion:
3509 From = ImpCastExprToType(From, ToType, CK_NoOp,
3510 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3513 case ICK_Writeback_Conversion:
3514 case ICK_Pointer_Conversion: {
3515 if (SCS.IncompatibleObjC && Action != AA_Casting) {
3516 // Diagnose incompatible Objective-C conversions
3517 if (Action == AA_Initializing || Action == AA_Assigning)
3518 Diag(From->getLocStart(),
3519 diag::ext_typecheck_convert_incompatible_pointer)
3520 << ToType << From->getType() << Action
3521 << From->getSourceRange() << 0;
3523 Diag(From->getLocStart(),
3524 diag::ext_typecheck_convert_incompatible_pointer)
3525 << From->getType() << ToType << Action
3526 << From->getSourceRange() << 0;
3528 if (From->getType()->isObjCObjectPointerType() &&
3529 ToType->isObjCObjectPointerType())
3530 EmitRelatedResultTypeNote(From);
3532 else if (getLangOpts().ObjCAutoRefCount &&
3533 !CheckObjCARCUnavailableWeakConversion(ToType,
3535 if (Action == AA_Initializing)
3536 Diag(From->getLocStart(),
3537 diag::err_arc_weak_unavailable_assign);
3539 Diag(From->getLocStart(),
3540 diag::err_arc_convesion_of_weak_unavailable)
3541 << (Action == AA_Casting) << From->getType() << ToType
3542 << From->getSourceRange();
3545 CastKind Kind = CK_Invalid;
3546 CXXCastPath BasePath;
3547 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle))
3550 // Make sure we extend blocks if necessary.
3551 // FIXME: doing this here is really ugly.
3552 if (Kind == CK_BlockPointerToObjCPointerCast) {
3553 ExprResult E = From;
3554 (void) PrepareCastToObjCObjectPointer(E);
3557 if (getLangOpts().ObjCAutoRefCount)
3558 CheckObjCARCConversion(SourceRange(), ToType, From, CCK);
3559 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
3564 case ICK_Pointer_Member: {
3565 CastKind Kind = CK_Invalid;
3566 CXXCastPath BasePath;
3567 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle))
3569 if (CheckExceptionSpecCompatibility(From, ToType))
3572 // We may not have been able to figure out what this member pointer resolved
3573 // to up until this exact point. Attempt to lock-in it's inheritance model.
3574 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
3575 (void)isCompleteType(From->getExprLoc(), From->getType());
3576 (void)isCompleteType(From->getExprLoc(), ToType);
3579 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
3584 case ICK_Boolean_Conversion:
3585 // Perform half-to-boolean conversion via float.
3586 if (From->getType()->isHalfType()) {
3587 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).get();
3588 FromType = Context.FloatTy;
3591 From = ImpCastExprToType(From, Context.BoolTy,
3592 ScalarTypeToBooleanCastKind(FromType),
3593 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3596 case ICK_Derived_To_Base: {
3597 CXXCastPath BasePath;
3598 if (CheckDerivedToBaseConversion(From->getType(),
3599 ToType.getNonReferenceType(),
3600 From->getLocStart(),
3601 From->getSourceRange(),
3606 From = ImpCastExprToType(From, ToType.getNonReferenceType(),
3607 CK_DerivedToBase, From->getValueKind(),
3608 &BasePath, CCK).get();
3612 case ICK_Vector_Conversion:
3613 From = ImpCastExprToType(From, ToType, CK_BitCast,
3614 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3617 case ICK_Vector_Splat: {
3618 // Vector splat from any arithmetic type to a vector.
3619 Expr *Elem = prepareVectorSplat(ToType, From).get();
3620 From = ImpCastExprToType(Elem, ToType, CK_VectorSplat, VK_RValue,
3621 /*BasePath=*/nullptr, CCK).get();
3625 case ICK_Complex_Real:
3626 // Case 1. x -> _Complex y
3627 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) {
3628 QualType ElType = ToComplex->getElementType();
3629 bool isFloatingComplex = ElType->isRealFloatingType();
3632 if (Context.hasSameUnqualifiedType(ElType, From->getType())) {
3634 } else if (From->getType()->isRealFloatingType()) {
3635 From = ImpCastExprToType(From, ElType,
3636 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).get();
3638 assert(From->getType()->isIntegerType());
3639 From = ImpCastExprToType(From, ElType,
3640 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).get();
3643 From = ImpCastExprToType(From, ToType,
3644 isFloatingComplex ? CK_FloatingRealToComplex
3645 : CK_IntegralRealToComplex).get();
3647 // Case 2. _Complex x -> y
3649 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>();
3650 assert(FromComplex);
3652 QualType ElType = FromComplex->getElementType();
3653 bool isFloatingComplex = ElType->isRealFloatingType();
3656 From = ImpCastExprToType(From, ElType,
3657 isFloatingComplex ? CK_FloatingComplexToReal
3658 : CK_IntegralComplexToReal,
3659 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3662 if (Context.hasSameUnqualifiedType(ElType, ToType)) {
3664 } else if (ToType->isRealFloatingType()) {
3665 From = ImpCastExprToType(From, ToType,
3666 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating,
3667 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3669 assert(ToType->isIntegerType());
3670 From = ImpCastExprToType(From, ToType,
3671 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast,
3672 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3677 case ICK_Block_Pointer_Conversion: {
3678 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast,
3679 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3683 case ICK_TransparentUnionConversion: {
3684 ExprResult FromRes = From;
3685 Sema::AssignConvertType ConvTy =
3686 CheckTransparentUnionArgumentConstraints(ToType, FromRes);
3687 if (FromRes.isInvalid())
3689 From = FromRes.get();
3690 assert ((ConvTy == Sema::Compatible) &&
3691 "Improper transparent union conversion");
3696 case ICK_Zero_Event_Conversion:
3697 From = ImpCastExprToType(From, ToType,
3699 From->getValueKind()).get();
3702 case ICK_Lvalue_To_Rvalue:
3703 case ICK_Array_To_Pointer:
3704 case ICK_Function_To_Pointer:
3705 case ICK_Qualification:
3706 case ICK_Num_Conversion_Kinds:
3707 case ICK_C_Only_Conversion:
3708 llvm_unreachable("Improper second standard conversion");
3711 switch (SCS.Third) {
3716 case ICK_Qualification: {
3717 // The qualification keeps the category of the inner expression, unless the
3718 // target type isn't a reference.
3719 ExprValueKind VK = ToType->isReferenceType() ?
3720 From->getValueKind() : VK_RValue;
3721 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context),
3722 CK_NoOp, VK, /*BasePath=*/nullptr, CCK).get();
3724 if (SCS.DeprecatedStringLiteralToCharPtr &&
3725 !getLangOpts().WritableStrings) {
3726 Diag(From->getLocStart(), getLangOpts().CPlusPlus11
3727 ? diag::ext_deprecated_string_literal_conversion
3728 : diag::warn_deprecated_string_literal_conversion)
3729 << ToType.getNonReferenceType();
3736 llvm_unreachable("Improper third standard conversion");
3739 // If this conversion sequence involved a scalar -> atomic conversion, perform
3740 // that conversion now.
3741 if (!ToAtomicType.isNull()) {
3742 assert(Context.hasSameType(
3743 ToAtomicType->castAs<AtomicType>()->getValueType(), From->getType()));
3744 From = ImpCastExprToType(From, ToAtomicType, CK_NonAtomicToAtomic,
3745 VK_RValue, nullptr, CCK).get();
3748 // If this conversion sequence succeeded and involved implicitly converting a
3749 // _Nullable type to a _Nonnull one, complain.
3750 if (CCK == CCK_ImplicitConversion)
3751 diagnoseNullableToNonnullConversion(ToType, InitialFromType,
3752 From->getLocStart());
3757 /// \brief Check the completeness of a type in a unary type trait.
3759 /// If the particular type trait requires a complete type, tries to complete
3760 /// it. If completing the type fails, a diagnostic is emitted and false
3761 /// returned. If completing the type succeeds or no completion was required,
3763 static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, TypeTrait UTT,
3766 // C++0x [meta.unary.prop]p3:
3767 // For all of the class templates X declared in this Clause, instantiating
3768 // that template with a template argument that is a class template
3769 // specialization may result in the implicit instantiation of the template
3770 // argument if and only if the semantics of X require that the argument
3771 // must be a complete type.
3772 // We apply this rule to all the type trait expressions used to implement
3773 // these class templates. We also try to follow any GCC documented behavior
3774 // in these expressions to ensure portability of standard libraries.
3776 default: llvm_unreachable("not a UTT");
3777 // is_complete_type somewhat obviously cannot require a complete type.
3778 case UTT_IsCompleteType:
3781 // These traits are modeled on the type predicates in C++0x
3782 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as
3783 // requiring a complete type, as whether or not they return true cannot be
3784 // impacted by the completeness of the type.
3786 case UTT_IsIntegral:
3787 case UTT_IsFloatingPoint:
3790 case UTT_IsLvalueReference:
3791 case UTT_IsRvalueReference:
3792 case UTT_IsMemberFunctionPointer:
3793 case UTT_IsMemberObjectPointer:
3797 case UTT_IsFunction:
3798 case UTT_IsReference:
3799 case UTT_IsArithmetic:
3800 case UTT_IsFundamental:
3803 case UTT_IsCompound:
3804 case UTT_IsMemberPointer:
3807 // These traits are modeled on type predicates in C++0x [meta.unary.prop]
3808 // which requires some of its traits to have the complete type. However,
3809 // the completeness of the type cannot impact these traits' semantics, and
3810 // so they don't require it. This matches the comments on these traits in
3813 case UTT_IsVolatile:
3815 case UTT_IsUnsigned:
3817 // This type trait always returns false, checking the type is moot.
3818 case UTT_IsInterfaceClass:
3821 // C++14 [meta.unary.prop]:
3822 // If T is a non-union class type, T shall be a complete type.
3824 case UTT_IsPolymorphic:
3825 case UTT_IsAbstract:
3826 if (const auto *RD = ArgTy->getAsCXXRecordDecl())
3828 return !S.RequireCompleteType(
3829 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
3832 // C++14 [meta.unary.prop]:
3833 // If T is a class type, T shall be a complete type.
3836 if (ArgTy->getAsCXXRecordDecl())
3837 return !S.RequireCompleteType(
3838 Loc, ArgTy, diag::err_incomplete_type_used_in_type_trait_expr);
3841 // C++0x [meta.unary.prop] Table 49 requires the following traits to be
3842 // applied to a complete type.
3844 case UTT_IsTriviallyCopyable:
3845 case UTT_IsStandardLayout:
3849 case UTT_IsDestructible:
3850 case UTT_IsNothrowDestructible:
3853 // These trait expressions are designed to help implement predicates in
3854 // [meta.unary.prop] despite not being named the same. They are specified
3855 // by both GCC and the Embarcadero C++ compiler, and require the complete
3856 // type due to the overarching C++0x type predicates being implemented
3857 // requiring the complete type.
3858 case UTT_HasNothrowAssign:
3859 case UTT_HasNothrowMoveAssign:
3860 case UTT_HasNothrowConstructor:
3861 case UTT_HasNothrowCopy:
3862 case UTT_HasTrivialAssign:
3863 case UTT_HasTrivialMoveAssign:
3864 case UTT_HasTrivialDefaultConstructor:
3865 case UTT_HasTrivialMoveConstructor:
3866 case UTT_HasTrivialCopy:
3867 case UTT_HasTrivialDestructor:
3868 case UTT_HasVirtualDestructor:
3869 // Arrays of unknown bound are expressly allowed.
3870 QualType ElTy = ArgTy;
3871 if (ArgTy->isIncompleteArrayType())
3872 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType();
3874 // The void type is expressly allowed.
3875 if (ElTy->isVoidType())
3878 return !S.RequireCompleteType(
3879 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr);
3883 static bool HasNoThrowOperator(const RecordType *RT, OverloadedOperatorKind Op,
3884 Sema &Self, SourceLocation KeyLoc, ASTContext &C,
3885 bool (CXXRecordDecl::*HasTrivial)() const,
3886 bool (CXXRecordDecl::*HasNonTrivial)() const,
3887 bool (CXXMethodDecl::*IsDesiredOp)() const)
3889 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3890 if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)())
3893 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op);
3894 DeclarationNameInfo NameInfo(Name, KeyLoc);
3895 LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName);
3896 if (Self.LookupQualifiedName(Res, RD)) {
3897 bool FoundOperator = false;
3898 Res.suppressDiagnostics();
3899 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end();
3900 Op != OpEnd; ++Op) {
3901 if (isa<FunctionTemplateDecl>(*Op))
3904 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op);
3905 if((Operator->*IsDesiredOp)()) {
3906 FoundOperator = true;
3907 const FunctionProtoType *CPT =
3908 Operator->getType()->getAs<FunctionProtoType>();
3909 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
3910 if (!CPT || !CPT->isNothrow(C))
3914 return FoundOperator;
3919 static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
3920 SourceLocation KeyLoc, QualType T) {
3921 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
3923 ASTContext &C = Self.Context;
3925 default: llvm_unreachable("not a UTT");
3926 // Type trait expressions corresponding to the primary type category
3927 // predicates in C++0x [meta.unary.cat].
3929 return T->isVoidType();
3930 case UTT_IsIntegral:
3931 return T->isIntegralType(C);
3932 case UTT_IsFloatingPoint:
3933 return T->isFloatingType();
3935 return T->isArrayType();
3937 return T->isPointerType();
3938 case UTT_IsLvalueReference:
3939 return T->isLValueReferenceType();
3940 case UTT_IsRvalueReference:
3941 return T->isRValueReferenceType();
3942 case UTT_IsMemberFunctionPointer:
3943 return T->isMemberFunctionPointerType();
3944 case UTT_IsMemberObjectPointer:
3945 return T->isMemberDataPointerType();
3947 return T->isEnumeralType();
3949 return T->isUnionType();
3951 return T->isClassType() || T->isStructureType() || T->isInterfaceType();
3952 case UTT_IsFunction:
3953 return T->isFunctionType();
3955 // Type trait expressions which correspond to the convenient composition
3956 // predicates in C++0x [meta.unary.comp].
3957 case UTT_IsReference:
3958 return T->isReferenceType();
3959 case UTT_IsArithmetic:
3960 return T->isArithmeticType() && !T->isEnumeralType();
3961 case UTT_IsFundamental:
3962 return T->isFundamentalType();
3964 return T->isObjectType();
3966 // Note: semantic analysis depends on Objective-C lifetime types to be
3967 // considered scalar types. However, such types do not actually behave
3968 // like scalar types at run time (since they may require retain/release
3969 // operations), so we report them as non-scalar.
3970 if (T->isObjCLifetimeType()) {
3971 switch (T.getObjCLifetime()) {
3972 case Qualifiers::OCL_None:
3973 case Qualifiers::OCL_ExplicitNone:
3976 case Qualifiers::OCL_Strong:
3977 case Qualifiers::OCL_Weak:
3978 case Qualifiers::OCL_Autoreleasing:
3983 return T->isScalarType();
3984 case UTT_IsCompound:
3985 return T->isCompoundType();
3986 case UTT_IsMemberPointer:
3987 return T->isMemberPointerType();
3989 // Type trait expressions which correspond to the type property predicates
3990 // in C++0x [meta.unary.prop].
3992 return T.isConstQualified();
3993 case UTT_IsVolatile:
3994 return T.isVolatileQualified();
3996 return T.isTrivialType(C);
3997 case UTT_IsTriviallyCopyable:
3998 return T.isTriviallyCopyableType(C);
3999 case UTT_IsStandardLayout:
4000 return T->isStandardLayoutType();
4002 return T.isPODType(C);
4004 return T->isLiteralType(C);
4006 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4007 return !RD->isUnion() && RD->isEmpty();
4009 case UTT_IsPolymorphic:
4010 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4011 return !RD->isUnion() && RD->isPolymorphic();
4013 case UTT_IsAbstract:
4014 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4015 return !RD->isUnion() && RD->isAbstract();
4017 // __is_interface_class only returns true when CL is invoked in /CLR mode and
4018 // even then only when it is used with the 'interface struct ...' syntax
4019 // Clang doesn't support /CLR which makes this type trait moot.
4020 case UTT_IsInterfaceClass:
4024 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4025 return RD->hasAttr<FinalAttr>();
4028 return T->isSignedIntegerType();
4029 case UTT_IsUnsigned:
4030 return T->isUnsignedIntegerType();
4032 // Type trait expressions which query classes regarding their construction,
4033 // destruction, and copying. Rather than being based directly on the
4034 // related type predicates in the standard, they are specified by both
4035 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those
4038 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
4039 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4041 // Note that these builtins do not behave as documented in g++: if a class
4042 // has both a trivial and a non-trivial special member of a particular kind,
4043 // they return false! For now, we emulate this behavior.
4044 // FIXME: This appears to be a g++ bug: more complex cases reveal that it
4045 // does not correctly compute triviality in the presence of multiple special
4046 // members of the same kind. Revisit this once the g++ bug is fixed.
4047 case UTT_HasTrivialDefaultConstructor:
4048 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4049 // If __is_pod (type) is true then the trait is true, else if type is
4050 // a cv class or union type (or array thereof) with a trivial default
4051 // constructor ([class.ctor]) then the trait is true, else it is false.
4054 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4055 return RD->hasTrivialDefaultConstructor() &&
4056 !RD->hasNonTrivialDefaultConstructor();
4058 case UTT_HasTrivialMoveConstructor:
4059 // This trait is implemented by MSVC 2012 and needed to parse the
4060 // standard library headers. Specifically this is used as the logic
4061 // behind std::is_trivially_move_constructible (20.9.4.3).
4064 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4065 return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor();
4067 case UTT_HasTrivialCopy:
4068 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4069 // If __is_pod (type) is true or type is a reference type then
4070 // the trait is true, else if type is a cv class or union type
4071 // with a trivial copy constructor ([class.copy]) then the trait
4072 // is true, else it is false.
4073 if (T.isPODType(C) || T->isReferenceType())
4075 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4076 return RD->hasTrivialCopyConstructor() &&
4077 !RD->hasNonTrivialCopyConstructor();
4079 case UTT_HasTrivialMoveAssign:
4080 // This trait is implemented by MSVC 2012 and needed to parse the
4081 // standard library headers. Specifically it is used as the logic
4082 // behind std::is_trivially_move_assignable (20.9.4.3)
4085 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4086 return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment();
4088 case UTT_HasTrivialAssign:
4089 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4090 // If type is const qualified or is a reference type then the
4091 // trait is false. Otherwise if __is_pod (type) is true then the
4092 // trait is true, else if type is a cv class or union type with
4093 // a trivial copy assignment ([class.copy]) then the trait is
4094 // true, else it is false.
4095 // Note: the const and reference restrictions are interesting,
4096 // given that const and reference members don't prevent a class
4097 // from having a trivial copy assignment operator (but do cause
4098 // errors if the copy assignment operator is actually used, q.v.
4099 // [class.copy]p12).
4101 if (T.isConstQualified())
4105 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4106 return RD->hasTrivialCopyAssignment() &&
4107 !RD->hasNonTrivialCopyAssignment();
4109 case UTT_IsDestructible:
4110 case UTT_IsNothrowDestructible:
4111 // C++14 [meta.unary.prop]:
4112 // For reference types, is_destructible<T>::value is true.
4113 if (T->isReferenceType())
4116 // Objective-C++ ARC: autorelease types don't require destruction.
4117 if (T->isObjCLifetimeType() &&
4118 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
4121 // C++14 [meta.unary.prop]:
4122 // For incomplete types and function types, is_destructible<T>::value is
4124 if (T->isIncompleteType() || T->isFunctionType())
4127 // C++14 [meta.unary.prop]:
4128 // For object types and given U equal to remove_all_extents_t<T>, if the
4129 // expression std::declval<U&>().~U() is well-formed when treated as an
4130 // unevaluated operand (Clause 5), then is_destructible<T>::value is true
4131 if (auto *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
4132 CXXDestructorDecl *Destructor = Self.LookupDestructor(RD);
4135 // C++14 [dcl.fct.def.delete]p2:
4136 // A program that refers to a deleted function implicitly or
4137 // explicitly, other than to declare it, is ill-formed.
4138 if (Destructor->isDeleted())
4140 if (C.getLangOpts().AccessControl && Destructor->getAccess() != AS_public)
4142 if (UTT == UTT_IsNothrowDestructible) {
4143 const FunctionProtoType *CPT =
4144 Destructor->getType()->getAs<FunctionProtoType>();
4145 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4146 if (!CPT || !CPT->isNothrow(C))
4152 case UTT_HasTrivialDestructor:
4153 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
4154 // If __is_pod (type) is true or type is a reference type
4155 // then the trait is true, else if type is a cv class or union
4156 // type (or array thereof) with a trivial destructor
4157 // ([class.dtor]) then the trait is true, else it is
4159 if (T.isPODType(C) || T->isReferenceType())
4162 // Objective-C++ ARC: autorelease types don't require destruction.
4163 if (T->isObjCLifetimeType() &&
4164 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
4167 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
4168 return RD->hasTrivialDestructor();
4170 // TODO: Propagate nothrowness for implicitly declared special members.
4171 case UTT_HasNothrowAssign:
4172 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4173 // If type is const qualified or is a reference type then the
4174 // trait is false. Otherwise if __has_trivial_assign (type)
4175 // is true then the trait is true, else if type is a cv class
4176 // or union type with copy assignment operators that are known
4177 // not to throw an exception then the trait is true, else it is
4179 if (C.getBaseElementType(T).isConstQualified())
4181 if (T->isReferenceType())
4183 if (T.isPODType(C) || T->isObjCLifetimeType())
4186 if (const RecordType *RT = T->getAs<RecordType>())
4187 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
4188 &CXXRecordDecl::hasTrivialCopyAssignment,
4189 &CXXRecordDecl::hasNonTrivialCopyAssignment,
4190 &CXXMethodDecl::isCopyAssignmentOperator);
4192 case UTT_HasNothrowMoveAssign:
4193 // This trait is implemented by MSVC 2012 and needed to parse the
4194 // standard library headers. Specifically this is used as the logic
4195 // behind std::is_nothrow_move_assignable (20.9.4.3).
4199 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>())
4200 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
4201 &CXXRecordDecl::hasTrivialMoveAssignment,
4202 &CXXRecordDecl::hasNonTrivialMoveAssignment,
4203 &CXXMethodDecl::isMoveAssignmentOperator);
4205 case UTT_HasNothrowCopy:
4206 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4207 // If __has_trivial_copy (type) is true then the trait is true, else
4208 // if type is a cv class or union type with copy constructors that are
4209 // known not to throw an exception then the trait is true, else it is
4211 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
4213 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
4214 if (RD->hasTrivialCopyConstructor() &&
4215 !RD->hasNonTrivialCopyConstructor())
4218 bool FoundConstructor = false;
4220 for (const auto *ND : Self.LookupConstructors(RD)) {
4221 // A template constructor is never a copy constructor.
4222 // FIXME: However, it may actually be selected at the actual overload
4223 // resolution point.
4224 if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
4226 // UsingDecl itself is not a constructor
4227 if (isa<UsingDecl>(ND))
4229 auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
4230 if (Constructor->isCopyConstructor(FoundTQs)) {
4231 FoundConstructor = true;
4232 const FunctionProtoType *CPT
4233 = Constructor->getType()->getAs<FunctionProtoType>();
4234 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4237 // TODO: check whether evaluating default arguments can throw.
4238 // For now, we'll be conservative and assume that they can throw.
4239 if (!CPT->isNothrow(C) || CPT->getNumParams() > 1)
4244 return FoundConstructor;
4247 case UTT_HasNothrowConstructor:
4248 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
4249 // If __has_trivial_constructor (type) is true then the trait is
4250 // true, else if type is a cv class or union type (or array
4251 // thereof) with a default constructor that is known not to
4252 // throw an exception then the trait is true, else it is false.
4253 if (T.isPODType(C) || T->isObjCLifetimeType())
4255 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
4256 if (RD->hasTrivialDefaultConstructor() &&
4257 !RD->hasNonTrivialDefaultConstructor())
4260 bool FoundConstructor = false;
4261 for (const auto *ND : Self.LookupConstructors(RD)) {
4262 // FIXME: In C++0x, a constructor template can be a default constructor.
4263 if (isa<FunctionTemplateDecl>(ND->getUnderlyingDecl()))
4265 // UsingDecl itself is not a constructor
4266 if (isa<UsingDecl>(ND))
4268 auto *Constructor = cast<CXXConstructorDecl>(ND->getUnderlyingDecl());
4269 if (Constructor->isDefaultConstructor()) {
4270 FoundConstructor = true;
4271 const FunctionProtoType *CPT
4272 = Constructor->getType()->getAs<FunctionProtoType>();
4273 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
4276 // FIXME: check whether evaluating default arguments can throw.
4277 // For now, we'll be conservative and assume that they can throw.
4278 if (!CPT->isNothrow(C) || CPT->getNumParams() > 0)
4282 return FoundConstructor;
4285 case UTT_HasVirtualDestructor:
4286 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
4287 // If type is a class type with a virtual destructor ([class.dtor])
4288 // then the trait is true, else it is false.
4289 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
4290 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
4291 return Destructor->isVirtual();
4294 // These type trait expressions are modeled on the specifications for the
4295 // Embarcadero C++0x type trait functions:
4296 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
4297 case UTT_IsCompleteType:
4298 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_):
4299 // Returns True if and only if T is a complete type at the point of the
4301 return !T->isIncompleteType();
4305 /// \brief Determine whether T has a non-trivial Objective-C lifetime in
4307 static bool hasNontrivialObjCLifetime(QualType T) {
4308 switch (T.getObjCLifetime()) {
4309 case Qualifiers::OCL_ExplicitNone:
4312 case Qualifiers::OCL_Strong:
4313 case Qualifiers::OCL_Weak:
4314 case Qualifiers::OCL_Autoreleasing:
4317 case Qualifiers::OCL_None:
4318 return T->isObjCLifetimeType();
4321 llvm_unreachable("Unknown ObjC lifetime qualifier");
4324 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
4325 QualType RhsT, SourceLocation KeyLoc);
4327 static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc,
4328 ArrayRef<TypeSourceInfo *> Args,
4329 SourceLocation RParenLoc) {
4330 if (Kind <= UTT_Last)
4331 return EvaluateUnaryTypeTrait(S, Kind, KWLoc, Args[0]->getType());
4333 if (Kind <= BTT_Last)
4334 return EvaluateBinaryTypeTrait(S, Kind, Args[0]->getType(),
4335 Args[1]->getType(), RParenLoc);
4338 case clang::TT_IsConstructible:
4339 case clang::TT_IsNothrowConstructible:
4340 case clang::TT_IsTriviallyConstructible: {
4341 // C++11 [meta.unary.prop]:
4342 // is_trivially_constructible is defined as:
4344 // is_constructible<T, Args...>::value is true and the variable
4345 // definition for is_constructible, as defined below, is known to call
4346 // no operation that is not trivial.
4348 // The predicate condition for a template specialization
4349 // is_constructible<T, Args...> shall be satisfied if and only if the
4350 // following variable definition would be well-formed for some invented
4353 // T t(create<Args>()...);
4354 assert(!Args.empty());
4356 // Precondition: T and all types in the parameter pack Args shall be
4357 // complete types, (possibly cv-qualified) void, or arrays of
4359 for (const auto *TSI : Args) {
4360 QualType ArgTy = TSI->getType();
4361 if (ArgTy->isVoidType() || ArgTy->isIncompleteArrayType())
4364 if (S.RequireCompleteType(KWLoc, ArgTy,
4365 diag::err_incomplete_type_used_in_type_trait_expr))
4369 // Make sure the first argument is not incomplete nor a function type.
4370 QualType T = Args[0]->getType();
4371 if (T->isIncompleteType() || T->isFunctionType())
4374 // Make sure the first argument is not an abstract type.
4375 CXXRecordDecl *RD = T->getAsCXXRecordDecl();
4376 if (RD && RD->isAbstract())
4379 SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs;
4380 SmallVector<Expr *, 2> ArgExprs;
4381 ArgExprs.reserve(Args.size() - 1);
4382 for (unsigned I = 1, N = Args.size(); I != N; ++I) {
4383 QualType ArgTy = Args[I]->getType();
4384 if (ArgTy->isObjectType() || ArgTy->isFunctionType())
4385 ArgTy = S.Context.getRValueReferenceType(ArgTy);
4386 OpaqueArgExprs.push_back(
4387 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(),
4388 ArgTy.getNonLValueExprType(S.Context),
4389 Expr::getValueKindForType(ArgTy)));
4391 for (Expr &E : OpaqueArgExprs)
4392 ArgExprs.push_back(&E);
4394 // Perform the initialization in an unevaluated context within a SFINAE
4395 // trap at translation unit scope.
4396 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated);
4397 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
4398 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl());
4399 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0]));
4400 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc,
4402 InitializationSequence Init(S, To, InitKind, ArgExprs);
4406 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs);
4407 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
4410 if (Kind == clang::TT_IsConstructible)
4413 if (Kind == clang::TT_IsNothrowConstructible)
4414 return S.canThrow(Result.get()) == CT_Cannot;
4416 if (Kind == clang::TT_IsTriviallyConstructible) {
4417 // Under Objective-C ARC, if the destination has non-trivial Objective-C
4418 // lifetime, this is a non-trivial construction.
4419 if (S.getLangOpts().ObjCAutoRefCount &&
4420 hasNontrivialObjCLifetime(T.getNonReferenceType()))
4423 // The initialization succeeded; now make sure there are no non-trivial
4425 return !Result.get()->hasNonTrivialCall(S.Context);
4428 llvm_unreachable("unhandled type trait");
4431 default: llvm_unreachable("not a TT");
4437 ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4438 ArrayRef<TypeSourceInfo *> Args,
4439 SourceLocation RParenLoc) {
4440 QualType ResultType = Context.getLogicalOperationType();
4442 if (Kind <= UTT_Last && !CheckUnaryTypeTraitTypeCompleteness(
4443 *this, Kind, KWLoc, Args[0]->getType()))
4446 bool Dependent = false;
4447 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
4448 if (Args[I]->getType()->isDependentType()) {
4454 bool Result = false;
4456 Result = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc);
4458 return TypeTraitExpr::Create(Context, ResultType, KWLoc, Kind, Args,
4462 ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4463 ArrayRef<ParsedType> Args,
4464 SourceLocation RParenLoc) {
4465 SmallVector<TypeSourceInfo *, 4> ConvertedArgs;
4466 ConvertedArgs.reserve(Args.size());
4468 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
4469 TypeSourceInfo *TInfo;
4470 QualType T = GetTypeFromParser(Args[I], &TInfo);
4472 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc);
4474 ConvertedArgs.push_back(TInfo);
4477 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc);
4480 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
4481 QualType RhsT, SourceLocation KeyLoc) {
4482 assert(!LhsT->isDependentType() && !RhsT->isDependentType() &&
4483 "Cannot evaluate traits of dependent types");
4486 case BTT_IsBaseOf: {
4487 // C++0x [meta.rel]p2
4488 // Base is a base class of Derived without regard to cv-qualifiers or
4489 // Base and Derived are not unions and name the same class type without
4490 // regard to cv-qualifiers.
4492 const RecordType *lhsRecord = LhsT->getAs<RecordType>();
4493 if (!lhsRecord) return false;
4495 const RecordType *rhsRecord = RhsT->getAs<RecordType>();
4496 if (!rhsRecord) return false;
4498 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT)
4499 == (lhsRecord == rhsRecord));
4501 if (lhsRecord == rhsRecord)
4502 return !lhsRecord->getDecl()->isUnion();
4504 // C++0x [meta.rel]p2:
4505 // If Base and Derived are class types and are different types
4506 // (ignoring possible cv-qualifiers) then Derived shall be a
4508 if (Self.RequireCompleteType(KeyLoc, RhsT,
4509 diag::err_incomplete_type_used_in_type_trait_expr))
4512 return cast<CXXRecordDecl>(rhsRecord->getDecl())
4513 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl()));
4516 return Self.Context.hasSameType(LhsT, RhsT);
4517 case BTT_TypeCompatible:
4518 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(),
4519 RhsT.getUnqualifiedType());
4520 case BTT_IsConvertible:
4521 case BTT_IsConvertibleTo: {
4522 // C++0x [meta.rel]p4:
4523 // Given the following function prototype:
4525 // template <class T>
4526 // typename add_rvalue_reference<T>::type create();
4528 // the predicate condition for a template specialization
4529 // is_convertible<From, To> shall be satisfied if and only if
4530 // the return expression in the following code would be
4531 // well-formed, including any implicit conversions to the return
4532 // type of the function:
4535 // return create<From>();
4538 // Access checking is performed as if in a context unrelated to To and
4539 // From. Only the validity of the immediate context of the expression
4540 // of the return-statement (including conversions to the return type)
4543 // We model the initialization as a copy-initialization of a temporary
4544 // of the appropriate type, which for this expression is identical to the
4545 // return statement (since NRVO doesn't apply).
4547 // Functions aren't allowed to return function or array types.
4548 if (RhsT->isFunctionType() || RhsT->isArrayType())
4551 // A return statement in a void function must have void type.
4552 if (RhsT->isVoidType())
4553 return LhsT->isVoidType();
4555 // A function definition requires a complete, non-abstract return type.
4556 if (!Self.isCompleteType(KeyLoc, RhsT) || Self.isAbstractType(KeyLoc, RhsT))
4559 // Compute the result of add_rvalue_reference.
4560 if (LhsT->isObjectType() || LhsT->isFunctionType())
4561 LhsT = Self.Context.getRValueReferenceType(LhsT);
4563 // Build a fake source and destination for initialization.
4564 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT));
4565 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
4566 Expr::getValueKindForType(LhsT));
4567 Expr *FromPtr = &From;
4568 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc,
4571 // Perform the initialization in an unevaluated context within a SFINAE
4572 // trap at translation unit scope.
4573 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated);
4574 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
4575 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
4576 InitializationSequence Init(Self, To, Kind, FromPtr);
4580 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr);
4581 return !Result.isInvalid() && !SFINAE.hasErrorOccurred();
4584 case BTT_IsAssignable:
4585 case BTT_IsNothrowAssignable:
4586 case BTT_IsTriviallyAssignable: {
4587 // C++11 [meta.unary.prop]p3:
4588 // is_trivially_assignable is defined as:
4589 // is_assignable<T, U>::value is true and the assignment, as defined by
4590 // is_assignable, is known to call no operation that is not trivial
4592 // is_assignable is defined as:
4593 // The expression declval<T>() = declval<U>() is well-formed when
4594 // treated as an unevaluated operand (Clause 5).
4596 // For both, T and U shall be complete types, (possibly cv-qualified)
4597 // void, or arrays of unknown bound.
4598 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() &&
4599 Self.RequireCompleteType(KeyLoc, LhsT,
4600 diag::err_incomplete_type_used_in_type_trait_expr))
4602 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() &&
4603 Self.RequireCompleteType(KeyLoc, RhsT,
4604 diag::err_incomplete_type_used_in_type_trait_expr))
4607 // cv void is never assignable.
4608 if (LhsT->isVoidType() || RhsT->isVoidType())
4611 // Build expressions that emulate the effect of declval<T>() and
4613 if (LhsT->isObjectType() || LhsT->isFunctionType())
4614 LhsT = Self.Context.getRValueReferenceType(LhsT);
4615 if (RhsT->isObjectType() || RhsT->isFunctionType())
4616 RhsT = Self.Context.getRValueReferenceType(RhsT);
4617 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
4618 Expr::getValueKindForType(LhsT));
4619 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context),
4620 Expr::getValueKindForType(RhsT));
4622 // Attempt the assignment in an unevaluated context within a SFINAE
4623 // trap at translation unit scope.
4624 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated);
4625 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
4626 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
4627 ExprResult Result = Self.BuildBinOp(/*S=*/nullptr, KeyLoc, BO_Assign, &Lhs,
4629 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
4632 if (BTT == BTT_IsAssignable)
4635 if (BTT == BTT_IsNothrowAssignable)
4636 return Self.canThrow(Result.get()) == CT_Cannot;
4638 if (BTT == BTT_IsTriviallyAssignable) {
4639 // Under Objective-C ARC, if the destination has non-trivial Objective-C
4640 // lifetime, this is a non-trivial assignment.
4641 if (Self.getLangOpts().ObjCAutoRefCount &&
4642 hasNontrivialObjCLifetime(LhsT.getNonReferenceType()))
4645 return !Result.get()->hasNonTrivialCall(Self.Context);
4648 llvm_unreachable("unhandled type trait");
4651 default: llvm_unreachable("not a BTT");
4653 llvm_unreachable("Unknown type trait or not implemented");
4656 ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT,
4657 SourceLocation KWLoc,
4660 SourceLocation RParen) {
4661 TypeSourceInfo *TSInfo;
4662 QualType T = GetTypeFromParser(Ty, &TSInfo);
4664 TSInfo = Context.getTrivialTypeSourceInfo(T);
4666 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen);
4669 static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT,
4670 QualType T, Expr *DimExpr,
4671 SourceLocation KeyLoc) {
4672 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
4676 if (T->isArrayType()) {
4678 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
4680 T = AT->getElementType();
4686 case ATT_ArrayExtent: {
4689 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value,
4690 diag::err_dimension_expr_not_constant_integer,
4693 if (Value.isSigned() && Value.isNegative()) {
4694 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer)
4695 << DimExpr->getSourceRange();
4698 Dim = Value.getLimitedValue();
4700 if (T->isArrayType()) {
4702 bool Matched = false;
4703 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
4709 T = AT->getElementType();
4712 if (Matched && T->isArrayType()) {
4713 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T))
4714 return CAT->getSize().getLimitedValue();
4720 llvm_unreachable("Unknown type trait or not implemented");
4723 ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT,
4724 SourceLocation KWLoc,
4725 TypeSourceInfo *TSInfo,
4727 SourceLocation RParen) {
4728 QualType T = TSInfo->getType();
4730 // FIXME: This should likely be tracked as an APInt to remove any host
4731 // assumptions about the width of size_t on the target.
4733 if (!T->isDependentType())
4734 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc);
4736 // While the specification for these traits from the Embarcadero C++
4737 // compiler's documentation says the return type is 'unsigned int', Clang
4738 // returns 'size_t'. On Windows, the primary platform for the Embarcadero
4739 // compiler, there is no difference. On several other platforms this is an
4740 // important distinction.
4741 return new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, DimExpr,
4742 RParen, Context.getSizeType());
4745 ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET,
4746 SourceLocation KWLoc,
4748 SourceLocation RParen) {
4749 // If error parsing the expression, ignore.
4753 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen);
4758 static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) {
4760 case ET_IsLValueExpr: return E->isLValue();
4761 case ET_IsRValueExpr: return E->isRValue();
4763 llvm_unreachable("Expression trait not covered by switch");
4766 ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET,
4767 SourceLocation KWLoc,
4769 SourceLocation RParen) {
4770 if (Queried->isTypeDependent()) {
4771 // Delay type-checking for type-dependent expressions.
4772 } else if (Queried->getType()->isPlaceholderType()) {
4773 ExprResult PE = CheckPlaceholderExpr(Queried);
4774 if (PE.isInvalid()) return ExprError();
4775 return BuildExpressionTrait(ET, KWLoc, PE.get(), RParen);
4778 bool Value = EvaluateExpressionTrait(ET, Queried);
4780 return new (Context)
4781 ExpressionTraitExpr(KWLoc, ET, Queried, Value, RParen, Context.BoolTy);
4784 QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS,
4788 assert(!LHS.get()->getType()->isPlaceholderType() &&
4789 !RHS.get()->getType()->isPlaceholderType() &&
4790 "placeholders should have been weeded out by now");
4792 // The LHS undergoes lvalue conversions if this is ->*.
4794 LHS = DefaultLvalueConversion(LHS.get());
4795 if (LHS.isInvalid()) return QualType();
4798 // The RHS always undergoes lvalue conversions.
4799 RHS = DefaultLvalueConversion(RHS.get());
4800 if (RHS.isInvalid()) return QualType();
4802 const char *OpSpelling = isIndirect ? "->*" : ".*";
4804 // The binary operator .* [p3: ->*] binds its second operand, which shall
4805 // be of type "pointer to member of T" (where T is a completely-defined
4806 // class type) [...]
4807 QualType RHSType = RHS.get()->getType();
4808 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>();
4810 Diag(Loc, diag::err_bad_memptr_rhs)
4811 << OpSpelling << RHSType << RHS.get()->getSourceRange();
4815 QualType Class(MemPtr->getClass(), 0);
4817 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the
4818 // member pointer points must be completely-defined. However, there is no
4819 // reason for this semantic distinction, and the rule is not enforced by
4820 // other compilers. Therefore, we do not check this property, as it is
4821 // likely to be considered a defect.
4824 // [...] to its first operand, which shall be of class T or of a class of
4825 // which T is an unambiguous and accessible base class. [p3: a pointer to
4827 QualType LHSType = LHS.get()->getType();
4829 if (const PointerType *Ptr = LHSType->getAs<PointerType>())
4830 LHSType = Ptr->getPointeeType();
4832 Diag(Loc, diag::err_bad_memptr_lhs)
4833 << OpSpelling << 1 << LHSType
4834 << FixItHint::CreateReplacement(SourceRange(Loc), ".*");
4839 if (!Context.hasSameUnqualifiedType(Class, LHSType)) {
4840 // If we want to check the hierarchy, we need a complete type.
4841 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs,
4842 OpSpelling, (int)isIndirect)) {
4846 if (!IsDerivedFrom(Loc, LHSType, Class)) {
4847 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling
4848 << (int)isIndirect << LHS.get()->getType();
4852 CXXCastPath BasePath;
4853 if (CheckDerivedToBaseConversion(LHSType, Class, Loc,
4854 SourceRange(LHS.get()->getLocStart(),
4855 RHS.get()->getLocEnd()),
4859 // Cast LHS to type of use.
4860 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class;
4861 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind();
4862 LHS = ImpCastExprToType(LHS.get(), UseType, CK_DerivedToBase, VK,
4866 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) {
4867 // Diagnose use of pointer-to-member type which when used as
4868 // the functional cast in a pointer-to-member expression.
4869 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect;
4874 // The result is an object or a function of the type specified by the
4876 // The cv qualifiers are the union of those in the pointer and the left side,
4877 // in accordance with 5.5p5 and 5.2.5.
4878 QualType Result = MemPtr->getPointeeType();
4879 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers());
4881 // C++0x [expr.mptr.oper]p6:
4882 // In a .* expression whose object expression is an rvalue, the program is
4883 // ill-formed if the second operand is a pointer to member function with
4884 // ref-qualifier &. In a ->* expression or in a .* expression whose object
4885 // expression is an lvalue, the program is ill-formed if the second operand
4886 // is a pointer to member function with ref-qualifier &&.
4887 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) {
4888 switch (Proto->getRefQualifier()) {
4894 if (!isIndirect && !LHS.get()->Classify(Context).isLValue())
4895 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
4896 << RHSType << 1 << LHS.get()->getSourceRange();
4900 if (isIndirect || !LHS.get()->Classify(Context).isRValue())
4901 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
4902 << RHSType << 0 << LHS.get()->getSourceRange();
4907 // C++ [expr.mptr.oper]p6:
4908 // The result of a .* expression whose second operand is a pointer
4909 // to a data member is of the same value category as its
4910 // first operand. The result of a .* expression whose second
4911 // operand is a pointer to a member function is a prvalue. The
4912 // result of an ->* expression is an lvalue if its second operand
4913 // is a pointer to data member and a prvalue otherwise.
4914 if (Result->isFunctionType()) {
4916 return Context.BoundMemberTy;
4917 } else if (isIndirect) {
4920 VK = LHS.get()->getValueKind();
4926 /// \brief Try to convert a type to another according to C++11 5.16p3.
4928 /// This is part of the parameter validation for the ? operator. If either
4929 /// value operand is a class type, the two operands are attempted to be
4930 /// converted to each other. This function does the conversion in one direction.
4931 /// It returns true if the program is ill-formed and has already been diagnosed
4933 static bool TryClassUnification(Sema &Self, Expr *From, Expr *To,
4934 SourceLocation QuestionLoc,
4935 bool &HaveConversion,
4937 HaveConversion = false;
4938 ToType = To->getType();
4940 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(),
4943 // The process for determining whether an operand expression E1 of type T1
4944 // can be converted to match an operand expression E2 of type T2 is defined
4946 // -- If E2 is an lvalue: E1 can be converted to match E2 if E1 can be
4947 // implicitly converted to type "lvalue reference to T2", subject to the
4948 // constraint that in the conversion the reference must bind directly to
4950 // -- If E2 is an xvalue: E1 can be converted to match E2 if E1 can be
4951 // implicitly conveted to the type "rvalue reference to R2", subject to
4952 // the constraint that the reference must bind directly.
4953 if (To->isLValue() || To->isXValue()) {
4954 QualType T = To->isLValue() ? Self.Context.getLValueReferenceType(ToType)
4955 : Self.Context.getRValueReferenceType(ToType);
4957 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
4959 InitializationSequence InitSeq(Self, Entity, Kind, From);
4960 if (InitSeq.isDirectReferenceBinding()) {
4962 HaveConversion = true;
4966 if (InitSeq.isAmbiguous())
4967 return InitSeq.Diagnose(Self, Entity, Kind, From);
4970 // -- If E2 is an rvalue, or if the conversion above cannot be done:
4971 // -- if E1 and E2 have class type, and the underlying class types are
4972 // the same or one is a base class of the other:
4973 QualType FTy = From->getType();
4974 QualType TTy = To->getType();
4975 const RecordType *FRec = FTy->getAs<RecordType>();
4976 const RecordType *TRec = TTy->getAs<RecordType>();
4977 bool FDerivedFromT = FRec && TRec && FRec != TRec &&
4978 Self.IsDerivedFrom(QuestionLoc, FTy, TTy);
4979 if (FRec && TRec && (FRec == TRec || FDerivedFromT ||
4980 Self.IsDerivedFrom(QuestionLoc, TTy, FTy))) {
4981 // E1 can be converted to match E2 if the class of T2 is the
4982 // same type as, or a base class of, the class of T1, and
4984 if (FRec == TRec || FDerivedFromT) {
4985 if (TTy.isAtLeastAsQualifiedAs(FTy)) {
4986 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
4987 InitializationSequence InitSeq(Self, Entity, Kind, From);
4989 HaveConversion = true;
4993 if (InitSeq.isAmbiguous())
4994 return InitSeq.Diagnose(Self, Entity, Kind, From);
5001 // -- Otherwise: E1 can be converted to match E2 if E1 can be
5002 // implicitly converted to the type that expression E2 would have
5003 // if E2 were converted to an rvalue (or the type it has, if E2 is
5006 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not
5007 // to the array-to-pointer or function-to-pointer conversions.
5008 if (!TTy->getAs<TagType>())
5009 TTy = TTy.getUnqualifiedType();
5011 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
5012 InitializationSequence InitSeq(Self, Entity, Kind, From);
5013 HaveConversion = !InitSeq.Failed();
5015 if (InitSeq.isAmbiguous())
5016 return InitSeq.Diagnose(Self, Entity, Kind, From);
5021 /// \brief Try to find a common type for two according to C++0x 5.16p5.
5023 /// This is part of the parameter validation for the ? operator. If either
5024 /// value operand is a class type, overload resolution is used to find a
5025 /// conversion to a common type.
5026 static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS,
5027 SourceLocation QuestionLoc) {
5028 Expr *Args[2] = { LHS.get(), RHS.get() };
5029 OverloadCandidateSet CandidateSet(QuestionLoc,
5030 OverloadCandidateSet::CSK_Operator);
5031 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args,
5034 OverloadCandidateSet::iterator Best;
5035 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) {
5037 // We found a match. Perform the conversions on the arguments and move on.
5039 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0],
5040 Best->Conversions[0], Sema::AA_Converting);
5041 if (LHSRes.isInvalid())
5046 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1],
5047 Best->Conversions[1], Sema::AA_Converting);
5048 if (RHSRes.isInvalid())
5052 Self.MarkFunctionReferenced(QuestionLoc, Best->Function);
5056 case OR_No_Viable_Function:
5058 // Emit a better diagnostic if one of the expressions is a null pointer
5059 // constant and the other is a pointer type. In this case, the user most
5060 // likely forgot to take the address of the other expression.
5061 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
5064 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
5065 << LHS.get()->getType() << RHS.get()->getType()
5066 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5070 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl)
5071 << LHS.get()->getType() << RHS.get()->getType()
5072 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5073 // FIXME: Print the possible common types by printing the return types of
5074 // the viable candidates.
5078 llvm_unreachable("Conditional operator has only built-in overloads");
5083 /// \brief Perform an "extended" implicit conversion as returned by
5084 /// TryClassUnification.
5085 static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) {
5086 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
5087 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(),
5089 Expr *Arg = E.get();
5090 InitializationSequence InitSeq(Self, Entity, Kind, Arg);
5091 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, Arg);
5092 if (Result.isInvalid())
5099 /// \brief Check the operands of ?: under C++ semantics.
5101 /// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y
5102 /// extension. In this case, LHS == Cond. (But they're not aliases.)
5103 QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
5104 ExprResult &RHS, ExprValueKind &VK,
5106 SourceLocation QuestionLoc) {
5107 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++
5108 // interface pointers.
5110 // C++11 [expr.cond]p1
5111 // The first expression is contextually converted to bool.
5112 if (!Cond.get()->isTypeDependent()) {
5113 ExprResult CondRes = CheckCXXBooleanCondition(Cond.get());
5114 if (CondRes.isInvalid())
5123 // Either of the arguments dependent?
5124 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent())
5125 return Context.DependentTy;
5127 // C++11 [expr.cond]p2
5128 // If either the second or the third operand has type (cv) void, ...
5129 QualType LTy = LHS.get()->getType();
5130 QualType RTy = RHS.get()->getType();
5131 bool LVoid = LTy->isVoidType();
5132 bool RVoid = RTy->isVoidType();
5133 if (LVoid || RVoid) {
5134 // ... one of the following shall hold:
5135 // -- The second or the third operand (but not both) is a (possibly
5136 // parenthesized) throw-expression; the result is of the type
5137 // and value category of the other.
5138 bool LThrow = isa<CXXThrowExpr>(LHS.get()->IgnoreParenImpCasts());
5139 bool RThrow = isa<CXXThrowExpr>(RHS.get()->IgnoreParenImpCasts());
5140 if (LThrow != RThrow) {
5141 Expr *NonThrow = LThrow ? RHS.get() : LHS.get();
5142 VK = NonThrow->getValueKind();
5143 // DR (no number yet): the result is a bit-field if the
5144 // non-throw-expression operand is a bit-field.
5145 OK = NonThrow->getObjectKind();
5146 return NonThrow->getType();
5149 // -- Both the second and third operands have type void; the result is of
5150 // type void and is a prvalue.
5152 return Context.VoidTy;
5154 // Neither holds, error.
5155 Diag(QuestionLoc, diag::err_conditional_void_nonvoid)
5156 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1)
5157 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5163 // C++11 [expr.cond]p3
5164 // Otherwise, if the second and third operand have different types, and
5165 // either has (cv) class type [...] an attempt is made to convert each of
5166 // those operands to the type of the other.
5167 if (!Context.hasSameType(LTy, RTy) &&
5168 (LTy->isRecordType() || RTy->isRecordType())) {
5169 // These return true if a single direction is already ambiguous.
5170 QualType L2RType, R2LType;
5171 bool HaveL2R, HaveR2L;
5172 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType))
5174 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType))
5177 // If both can be converted, [...] the program is ill-formed.
5178 if (HaveL2R && HaveR2L) {
5179 Diag(QuestionLoc, diag::err_conditional_ambiguous)
5180 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5184 // If exactly one conversion is possible, that conversion is applied to
5185 // the chosen operand and the converted operands are used in place of the
5186 // original operands for the remainder of this section.
5188 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid())
5190 LTy = LHS.get()->getType();
5191 } else if (HaveR2L) {
5192 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid())
5194 RTy = RHS.get()->getType();
5198 // C++11 [expr.cond]p3
5199 // if both are glvalues of the same value category and the same type except
5200 // for cv-qualification, an attempt is made to convert each of those
5201 // operands to the type of the other.
5202 ExprValueKind LVK = LHS.get()->getValueKind();
5203 ExprValueKind RVK = RHS.get()->getValueKind();
5204 if (!Context.hasSameType(LTy, RTy) &&
5205 Context.hasSameUnqualifiedType(LTy, RTy) &&
5206 LVK == RVK && LVK != VK_RValue) {
5207 // Since the unqualified types are reference-related and we require the
5208 // result to be as if a reference bound directly, the only conversion
5209 // we can perform is to add cv-qualifiers.
5210 Qualifiers LCVR = Qualifiers::fromCVRMask(LTy.getCVRQualifiers());
5211 Qualifiers RCVR = Qualifiers::fromCVRMask(RTy.getCVRQualifiers());
5212 if (RCVR.isStrictSupersetOf(LCVR)) {
5213 LHS = ImpCastExprToType(LHS.get(), RTy, CK_NoOp, LVK);
5214 LTy = LHS.get()->getType();
5216 else if (LCVR.isStrictSupersetOf(RCVR)) {
5217 RHS = ImpCastExprToType(RHS.get(), LTy, CK_NoOp, RVK);
5218 RTy = RHS.get()->getType();
5222 // C++11 [expr.cond]p4
5223 // If the second and third operands are glvalues of the same value
5224 // category and have the same type, the result is of that type and
5225 // value category and it is a bit-field if the second or the third
5226 // operand is a bit-field, or if both are bit-fields.
5227 // We only extend this to bitfields, not to the crazy other kinds of
5229 bool Same = Context.hasSameType(LTy, RTy);
5230 if (Same && LVK == RVK && LVK != VK_RValue &&
5231 LHS.get()->isOrdinaryOrBitFieldObject() &&
5232 RHS.get()->isOrdinaryOrBitFieldObject()) {
5233 VK = LHS.get()->getValueKind();
5234 if (LHS.get()->getObjectKind() == OK_BitField ||
5235 RHS.get()->getObjectKind() == OK_BitField)
5240 // C++11 [expr.cond]p5
5241 // Otherwise, the result is a prvalue. If the second and third operands
5242 // do not have the same type, and either has (cv) class type, ...
5243 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) {
5244 // ... overload resolution is used to determine the conversions (if any)
5245 // to be applied to the operands. If the overload resolution fails, the
5246 // program is ill-formed.
5247 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc))
5251 // C++11 [expr.cond]p6
5252 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard
5253 // conversions are performed on the second and third operands.
5254 LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
5255 RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
5256 if (LHS.isInvalid() || RHS.isInvalid())
5258 LTy = LHS.get()->getType();
5259 RTy = RHS.get()->getType();
5261 // After those conversions, one of the following shall hold:
5262 // -- The second and third operands have the same type; the result
5263 // is of that type. If the operands have class type, the result
5264 // is a prvalue temporary of the result type, which is
5265 // copy-initialized from either the second operand or the third
5266 // operand depending on the value of the first operand.
5267 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) {
5268 if (LTy->isRecordType()) {
5269 // The operands have class type. Make a temporary copy.
5270 if (RequireNonAbstractType(QuestionLoc, LTy,
5271 diag::err_allocation_of_abstract_type))
5273 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy);
5275 ExprResult LHSCopy = PerformCopyInitialization(Entity,
5278 if (LHSCopy.isInvalid())
5281 ExprResult RHSCopy = PerformCopyInitialization(Entity,
5284 if (RHSCopy.isInvalid())
5294 // Extension: conditional operator involving vector types.
5295 if (LTy->isVectorType() || RTy->isVectorType())
5296 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false,
5297 /*AllowBothBool*/true,
5298 /*AllowBoolConversions*/false);
5300 // -- The second and third operands have arithmetic or enumeration type;
5301 // the usual arithmetic conversions are performed to bring them to a
5302 // common type, and the result is of that type.
5303 if (LTy->isArithmeticType() && RTy->isArithmeticType()) {
5304 QualType ResTy = UsualArithmeticConversions(LHS, RHS);
5305 if (LHS.isInvalid() || RHS.isInvalid())
5307 if (ResTy.isNull()) {
5309 diag::err_typecheck_cond_incompatible_operands) << LTy << RTy
5310 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5314 LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
5315 RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
5320 // -- The second and third operands have pointer type, or one has pointer
5321 // type and the other is a null pointer constant, or both are null
5322 // pointer constants, at least one of which is non-integral; pointer
5323 // conversions and qualification conversions are performed to bring them
5324 // to their composite pointer type. The result is of the composite
5326 // -- The second and third operands have pointer to member type, or one has
5327 // pointer to member type and the other is a null pointer constant;
5328 // pointer to member conversions and qualification conversions are
5329 // performed to bring them to a common type, whose cv-qualification
5330 // shall match the cv-qualification of either the second or the third
5331 // operand. The result is of the common type.
5332 bool NonStandardCompositeType = false;
5333 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS,
5334 isSFINAEContext() ? nullptr
5335 : &NonStandardCompositeType);
5336 if (!Composite.isNull()) {
5337 if (NonStandardCompositeType)
5339 diag::ext_typecheck_cond_incompatible_operands_nonstandard)
5340 << LTy << RTy << Composite
5341 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5346 // Similarly, attempt to find composite type of two objective-c pointers.
5347 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc);
5348 if (!Composite.isNull())
5351 // Check if we are using a null with a non-pointer type.
5352 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
5355 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
5356 << LHS.get()->getType() << RHS.get()->getType()
5357 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5361 /// \brief Find a merged pointer type and convert the two expressions to it.
5363 /// This finds the composite pointer type (or member pointer type) for @p E1
5364 /// and @p E2 according to C++11 5.9p2. It converts both expressions to this
5365 /// type and returns it.
5366 /// It does not emit diagnostics.
5368 /// \param Loc The location of the operator requiring these two expressions to
5369 /// be converted to the composite pointer type.
5371 /// If \p NonStandardCompositeType is non-NULL, then we are permitted to find
5372 /// a non-standard (but still sane) composite type to which both expressions
5373 /// can be converted. When such a type is chosen, \c *NonStandardCompositeType
5374 /// will be set true.
5375 QualType Sema::FindCompositePointerType(SourceLocation Loc,
5376 Expr *&E1, Expr *&E2,
5377 bool *NonStandardCompositeType) {
5378 if (NonStandardCompositeType)
5379 *NonStandardCompositeType = false;
5381 assert(getLangOpts().CPlusPlus && "This function assumes C++");
5382 QualType T1 = E1->getType(), T2 = E2->getType();
5385 // Pointer conversions and qualification conversions are performed on
5386 // pointer operands to bring them to their composite pointer type. If
5387 // one operand is a null pointer constant, the composite pointer type is
5388 // std::nullptr_t if the other operand is also a null pointer constant or,
5389 // if the other operand is a pointer, the type of the other operand.
5390 if (!T1->isAnyPointerType() && !T1->isMemberPointerType() &&
5391 !T2->isAnyPointerType() && !T2->isMemberPointerType()) {
5392 if (T1->isNullPtrType() &&
5393 E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5394 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).get();
5397 if (T2->isNullPtrType() &&
5398 E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5399 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).get();
5405 if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5406 if (T2->isMemberPointerType())
5407 E1 = ImpCastExprToType(E1, T2, CK_NullToMemberPointer).get();
5409 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).get();
5412 if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5413 if (T1->isMemberPointerType())
5414 E2 = ImpCastExprToType(E2, T1, CK_NullToMemberPointer).get();
5416 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).get();
5420 // Now both have to be pointers or member pointers.
5421 if ((!T1->isPointerType() && !T1->isMemberPointerType()) ||
5422 (!T2->isPointerType() && !T2->isMemberPointerType()))
5425 // Otherwise, of one of the operands has type "pointer to cv1 void," then
5426 // the other has type "pointer to cv2 T" and the composite pointer type is
5427 // "pointer to cv12 void," where cv12 is the union of cv1 and cv2.
5428 // Otherwise, the composite pointer type is a pointer type similar to the
5429 // type of one of the operands, with a cv-qualification signature that is
5430 // the union of the cv-qualification signatures of the operand types.
5431 // In practice, the first part here is redundant; it's subsumed by the second.
5432 // What we do here is, we build the two possible composite types, and try the
5433 // conversions in both directions. If only one works, or if the two composite
5434 // types are the same, we have succeeded.
5435 // FIXME: extended qualifiers?
5436 typedef SmallVector<unsigned, 4> QualifierVector;
5437 QualifierVector QualifierUnion;
5438 typedef SmallVector<std::pair<const Type *, const Type *>, 4>
5439 ContainingClassVector;
5440 ContainingClassVector MemberOfClass;
5441 QualType Composite1 = Context.getCanonicalType(T1),
5442 Composite2 = Context.getCanonicalType(T2);
5443 unsigned NeedConstBefore = 0;
5445 const PointerType *Ptr1, *Ptr2;
5446 if ((Ptr1 = Composite1->getAs<PointerType>()) &&
5447 (Ptr2 = Composite2->getAs<PointerType>())) {
5448 Composite1 = Ptr1->getPointeeType();
5449 Composite2 = Ptr2->getPointeeType();
5451 // If we're allowed to create a non-standard composite type, keep track
5452 // of where we need to fill in additional 'const' qualifiers.
5453 if (NonStandardCompositeType &&
5454 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
5455 NeedConstBefore = QualifierUnion.size();
5457 QualifierUnion.push_back(
5458 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
5459 MemberOfClass.push_back(std::make_pair(nullptr, nullptr));
5463 const MemberPointerType *MemPtr1, *MemPtr2;
5464 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) &&
5465 (MemPtr2 = Composite2->getAs<MemberPointerType>())) {
5466 Composite1 = MemPtr1->getPointeeType();
5467 Composite2 = MemPtr2->getPointeeType();
5469 // If we're allowed to create a non-standard composite type, keep track
5470 // of where we need to fill in additional 'const' qualifiers.
5471 if (NonStandardCompositeType &&
5472 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
5473 NeedConstBefore = QualifierUnion.size();
5475 QualifierUnion.push_back(
5476 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
5477 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(),
5478 MemPtr2->getClass()));
5482 // FIXME: block pointer types?
5484 // Cannot unwrap any more types.
5488 if (NeedConstBefore && NonStandardCompositeType) {
5489 // Extension: Add 'const' to qualifiers that come before the first qualifier
5490 // mismatch, so that our (non-standard!) composite type meets the
5491 // requirements of C++ [conv.qual]p4 bullet 3.
5492 for (unsigned I = 0; I != NeedConstBefore; ++I) {
5493 if ((QualifierUnion[I] & Qualifiers::Const) == 0) {
5494 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const;
5495 *NonStandardCompositeType = true;
5500 // Rewrap the composites as pointers or member pointers with the union CVRs.
5501 ContainingClassVector::reverse_iterator MOC
5502 = MemberOfClass.rbegin();
5503 for (QualifierVector::reverse_iterator
5504 I = QualifierUnion.rbegin(),
5505 E = QualifierUnion.rend();
5506 I != E; (void)++I, ++MOC) {
5507 Qualifiers Quals = Qualifiers::fromCVRMask(*I);
5508 if (MOC->first && MOC->second) {
5509 // Rebuild member pointer type
5510 Composite1 = Context.getMemberPointerType(
5511 Context.getQualifiedType(Composite1, Quals),
5513 Composite2 = Context.getMemberPointerType(
5514 Context.getQualifiedType(Composite2, Quals),
5517 // Rebuild pointer type
5519 = Context.getPointerType(Context.getQualifiedType(Composite1, Quals));
5521 = Context.getPointerType(Context.getQualifiedType(Composite2, Quals));
5525 // Try to convert to the first composite pointer type.
5526 InitializedEntity Entity1
5527 = InitializedEntity::InitializeTemporary(Composite1);
5528 InitializationKind Kind
5529 = InitializationKind::CreateCopy(Loc, SourceLocation());
5530 InitializationSequence E1ToC1(*this, Entity1, Kind, E1);
5531 InitializationSequence E2ToC1(*this, Entity1, Kind, E2);
5533 if (E1ToC1 && E2ToC1) {
5534 // Conversion to Composite1 is viable.
5535 if (!Context.hasSameType(Composite1, Composite2)) {
5536 // Composite2 is a different type from Composite1. Check whether
5537 // Composite2 is also viable.
5538 InitializedEntity Entity2
5539 = InitializedEntity::InitializeTemporary(Composite2);
5540 InitializationSequence E1ToC2(*this, Entity2, Kind, E1);
5541 InitializationSequence E2ToC2(*this, Entity2, Kind, E2);
5542 if (E1ToC2 && E2ToC2) {
5543 // Both Composite1 and Composite2 are viable and are different;
5544 // this is an ambiguity.
5549 // Convert E1 to Composite1
5551 = E1ToC1.Perform(*this, Entity1, Kind, E1);
5552 if (E1Result.isInvalid())
5554 E1 = E1Result.getAs<Expr>();
5556 // Convert E2 to Composite1
5558 = E2ToC1.Perform(*this, Entity1, Kind, E2);
5559 if (E2Result.isInvalid())
5561 E2 = E2Result.getAs<Expr>();
5566 // Check whether Composite2 is viable.
5567 InitializedEntity Entity2
5568 = InitializedEntity::InitializeTemporary(Composite2);
5569 InitializationSequence E1ToC2(*this, Entity2, Kind, E1);
5570 InitializationSequence E2ToC2(*this, Entity2, Kind, E2);
5571 if (!E1ToC2 || !E2ToC2)
5574 // Convert E1 to Composite2
5576 = E1ToC2.Perform(*this, Entity2, Kind, E1);
5577 if (E1Result.isInvalid())
5579 E1 = E1Result.getAs<Expr>();
5581 // Convert E2 to Composite2
5583 = E2ToC2.Perform(*this, Entity2, Kind, E2);
5584 if (E2Result.isInvalid())
5586 E2 = E2Result.getAs<Expr>();
5591 ExprResult Sema::MaybeBindToTemporary(Expr *E) {
5595 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?");
5597 // If the result is a glvalue, we shouldn't bind it.
5601 // In ARC, calls that return a retainable type can return retained,
5602 // in which case we have to insert a consuming cast.
5603 if (getLangOpts().ObjCAutoRefCount &&
5604 E->getType()->isObjCRetainableType()) {
5606 bool ReturnsRetained;
5608 // For actual calls, we compute this by examining the type of the
5610 if (CallExpr *Call = dyn_cast<CallExpr>(E)) {
5611 Expr *Callee = Call->getCallee()->IgnoreParens();
5612 QualType T = Callee->getType();
5614 if (T == Context.BoundMemberTy) {
5615 // Handle pointer-to-members.
5616 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee))
5617 T = BinOp->getRHS()->getType();
5618 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee))
5619 T = Mem->getMemberDecl()->getType();
5622 if (const PointerType *Ptr = T->getAs<PointerType>())
5623 T = Ptr->getPointeeType();
5624 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>())
5625 T = Ptr->getPointeeType();
5626 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>())
5627 T = MemPtr->getPointeeType();
5629 const FunctionType *FTy = T->getAs<FunctionType>();
5630 assert(FTy && "call to value not of function type?");
5631 ReturnsRetained = FTy->getExtInfo().getProducesResult();
5633 // ActOnStmtExpr arranges things so that StmtExprs of retainable
5634 // type always produce a +1 object.
5635 } else if (isa<StmtExpr>(E)) {
5636 ReturnsRetained = true;
5638 // We hit this case with the lambda conversion-to-block optimization;
5639 // we don't want any extra casts here.
5640 } else if (isa<CastExpr>(E) &&
5641 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) {
5644 // For message sends and property references, we try to find an
5645 // actual method. FIXME: we should infer retention by selector in
5646 // cases where we don't have an actual method.
5648 ObjCMethodDecl *D = nullptr;
5649 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) {
5650 D = Send->getMethodDecl();
5651 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) {
5652 D = BoxedExpr->getBoxingMethod();
5653 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) {
5654 D = ArrayLit->getArrayWithObjectsMethod();
5655 } else if (ObjCDictionaryLiteral *DictLit
5656 = dyn_cast<ObjCDictionaryLiteral>(E)) {
5657 D = DictLit->getDictWithObjectsMethod();
5660 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>());
5662 // Don't do reclaims on performSelector calls; despite their
5663 // return type, the invoked method doesn't necessarily actually
5664 // return an object.
5665 if (!ReturnsRetained &&
5666 D && D->getMethodFamily() == OMF_performSelector)
5670 // Don't reclaim an object of Class type.
5671 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType())
5674 Cleanup.setExprNeedsCleanups(true);
5676 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject
5677 : CK_ARCReclaimReturnedObject);
5678 return ImplicitCastExpr::Create(Context, E->getType(), ck, E, nullptr,
5682 if (!getLangOpts().CPlusPlus)
5685 // Search for the base element type (cf. ASTContext::getBaseElementType) with
5686 // a fast path for the common case that the type is directly a RecordType.
5687 const Type *T = Context.getCanonicalType(E->getType().getTypePtr());
5688 const RecordType *RT = nullptr;
5690 switch (T->getTypeClass()) {
5692 RT = cast<RecordType>(T);
5694 case Type::ConstantArray:
5695 case Type::IncompleteArray:
5696 case Type::VariableArray:
5697 case Type::DependentSizedArray:
5698 T = cast<ArrayType>(T)->getElementType().getTypePtr();
5705 // That should be enough to guarantee that this type is complete, if we're
5706 // not processing a decltype expression.
5707 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
5708 if (RD->isInvalidDecl() || RD->isDependentContext())
5711 bool IsDecltype = ExprEvalContexts.back().IsDecltype;
5712 CXXDestructorDecl *Destructor = IsDecltype ? nullptr : LookupDestructor(RD);
5715 MarkFunctionReferenced(E->getExprLoc(), Destructor);
5716 CheckDestructorAccess(E->getExprLoc(), Destructor,
5717 PDiag(diag::err_access_dtor_temp)
5719 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
5722 // If destructor is trivial, we can avoid the extra copy.
5723 if (Destructor->isTrivial())
5726 // We need a cleanup, but we don't need to remember the temporary.
5727 Cleanup.setExprNeedsCleanups(true);
5730 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor);
5731 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E);
5734 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind);
5740 Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) {
5741 if (SubExpr.isInvalid())
5744 return MaybeCreateExprWithCleanups(SubExpr.get());
5747 Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) {
5748 assert(SubExpr && "subexpression can't be null!");
5750 CleanupVarDeclMarking();
5752 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects;
5753 assert(ExprCleanupObjects.size() >= FirstCleanup);
5754 assert(Cleanup.exprNeedsCleanups() ||
5755 ExprCleanupObjects.size() == FirstCleanup);
5756 if (!Cleanup.exprNeedsCleanups())
5759 auto Cleanups = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup,
5760 ExprCleanupObjects.size() - FirstCleanup);
5762 auto *E = ExprWithCleanups::Create(
5763 Context, SubExpr, Cleanup.cleanupsHaveSideEffects(), Cleanups);
5764 DiscardCleanupsInEvaluationContext();
5769 Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) {
5770 assert(SubStmt && "sub-statement can't be null!");
5772 CleanupVarDeclMarking();
5774 if (!Cleanup.exprNeedsCleanups())
5777 // FIXME: In order to attach the temporaries, wrap the statement into
5778 // a StmtExpr; currently this is only used for asm statements.
5779 // This is hacky, either create a new CXXStmtWithTemporaries statement or
5780 // a new AsmStmtWithTemporaries.
5781 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, SubStmt,
5784 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(),
5786 return MaybeCreateExprWithCleanups(E);
5789 /// Process the expression contained within a decltype. For such expressions,
5790 /// certain semantic checks on temporaries are delayed until this point, and
5791 /// are omitted for the 'topmost' call in the decltype expression. If the
5792 /// topmost call bound a temporary, strip that temporary off the expression.
5793 ExprResult Sema::ActOnDecltypeExpression(Expr *E) {
5794 assert(ExprEvalContexts.back().IsDecltype && "not in a decltype expression");
5796 // C++11 [expr.call]p11:
5797 // If a function call is a prvalue of object type,
5798 // -- if the function call is either
5799 // -- the operand of a decltype-specifier, or
5800 // -- the right operand of a comma operator that is the operand of a
5801 // decltype-specifier,
5802 // a temporary object is not introduced for the prvalue.
5804 // Recursively rebuild ParenExprs and comma expressions to strip out the
5805 // outermost CXXBindTemporaryExpr, if any.
5806 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
5807 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr());
5808 if (SubExpr.isInvalid())
5810 if (SubExpr.get() == PE->getSubExpr())
5812 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.get());
5814 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
5815 if (BO->getOpcode() == BO_Comma) {
5816 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS());
5817 if (RHS.isInvalid())
5819 if (RHS.get() == BO->getRHS())
5821 return new (Context) BinaryOperator(
5822 BO->getLHS(), RHS.get(), BO_Comma, BO->getType(), BO->getValueKind(),
5823 BO->getObjectKind(), BO->getOperatorLoc(), BO->isFPContractable());
5827 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E);
5828 CallExpr *TopCall = TopBind ? dyn_cast<CallExpr>(TopBind->getSubExpr())
5835 // Disable the special decltype handling now.
5836 ExprEvalContexts.back().IsDecltype = false;
5838 // In MS mode, don't perform any extra checking of call return types within a
5839 // decltype expression.
5840 if (getLangOpts().MSVCCompat)
5843 // Perform the semantic checks we delayed until this point.
5844 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size();
5846 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I];
5847 if (Call == TopCall)
5850 if (CheckCallReturnType(Call->getCallReturnType(Context),
5851 Call->getLocStart(),
5852 Call, Call->getDirectCallee()))
5856 // Now all relevant types are complete, check the destructors are accessible
5857 // and non-deleted, and annotate them on the temporaries.
5858 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size();
5860 CXXBindTemporaryExpr *Bind =
5861 ExprEvalContexts.back().DelayedDecltypeBinds[I];
5862 if (Bind == TopBind)
5865 CXXTemporary *Temp = Bind->getTemporary();
5868 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
5869 CXXDestructorDecl *Destructor = LookupDestructor(RD);
5870 Temp->setDestructor(Destructor);
5872 MarkFunctionReferenced(Bind->getExprLoc(), Destructor);
5873 CheckDestructorAccess(Bind->getExprLoc(), Destructor,
5874 PDiag(diag::err_access_dtor_temp)
5875 << Bind->getType());
5876 if (DiagnoseUseOfDecl(Destructor, Bind->getExprLoc()))
5879 // We need a cleanup, but we don't need to remember the temporary.
5880 Cleanup.setExprNeedsCleanups(true);
5883 // Possibly strip off the top CXXBindTemporaryExpr.
5887 /// Note a set of 'operator->' functions that were used for a member access.
5888 static void noteOperatorArrows(Sema &S,
5889 ArrayRef<FunctionDecl *> OperatorArrows) {
5890 unsigned SkipStart = OperatorArrows.size(), SkipCount = 0;
5891 // FIXME: Make this configurable?
5893 if (OperatorArrows.size() > Limit) {
5894 // Produce Limit-1 normal notes and one 'skipping' note.
5895 SkipStart = (Limit - 1) / 2 + (Limit - 1) % 2;
5896 SkipCount = OperatorArrows.size() - (Limit - 1);
5899 for (unsigned I = 0; I < OperatorArrows.size(); /**/) {
5900 if (I == SkipStart) {
5901 S.Diag(OperatorArrows[I]->getLocation(),
5902 diag::note_operator_arrows_suppressed)
5906 S.Diag(OperatorArrows[I]->getLocation(), diag::note_operator_arrow_here)
5907 << OperatorArrows[I]->getCallResultType();
5913 ExprResult Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base,
5914 SourceLocation OpLoc,
5915 tok::TokenKind OpKind,
5916 ParsedType &ObjectType,
5917 bool &MayBePseudoDestructor) {
5918 // Since this might be a postfix expression, get rid of ParenListExprs.
5919 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base);
5920 if (Result.isInvalid()) return ExprError();
5921 Base = Result.get();
5923 Result = CheckPlaceholderExpr(Base);
5924 if (Result.isInvalid()) return ExprError();
5925 Base = Result.get();
5927 QualType BaseType = Base->getType();
5928 MayBePseudoDestructor = false;
5929 if (BaseType->isDependentType()) {
5930 // If we have a pointer to a dependent type and are using the -> operator,
5931 // the object type is the type that the pointer points to. We might still
5932 // have enough information about that type to do something useful.
5933 if (OpKind == tok::arrow)
5934 if (const PointerType *Ptr = BaseType->getAs<PointerType>())
5935 BaseType = Ptr->getPointeeType();
5937 ObjectType = ParsedType::make(BaseType);
5938 MayBePseudoDestructor = true;
5942 // C++ [over.match.oper]p8:
5943 // [...] When operator->returns, the operator-> is applied to the value
5944 // returned, with the original second operand.
5945 if (OpKind == tok::arrow) {
5946 QualType StartingType = BaseType;
5947 bool NoArrowOperatorFound = false;
5948 bool FirstIteration = true;
5949 FunctionDecl *CurFD = dyn_cast<FunctionDecl>(CurContext);
5950 // The set of types we've considered so far.
5951 llvm::SmallPtrSet<CanQualType,8> CTypes;
5952 SmallVector<FunctionDecl*, 8> OperatorArrows;
5953 CTypes.insert(Context.getCanonicalType(BaseType));
5955 while (BaseType->isRecordType()) {
5956 if (OperatorArrows.size() >= getLangOpts().ArrowDepth) {
5957 Diag(OpLoc, diag::err_operator_arrow_depth_exceeded)
5958 << StartingType << getLangOpts().ArrowDepth << Base->getSourceRange();
5959 noteOperatorArrows(*this, OperatorArrows);
5960 Diag(OpLoc, diag::note_operator_arrow_depth)
5961 << getLangOpts().ArrowDepth;
5965 Result = BuildOverloadedArrowExpr(
5967 // When in a template specialization and on the first loop iteration,
5968 // potentially give the default diagnostic (with the fixit in a
5969 // separate note) instead of having the error reported back to here
5970 // and giving a diagnostic with a fixit attached to the error itself.
5971 (FirstIteration && CurFD && CurFD->isFunctionTemplateSpecialization())
5973 : &NoArrowOperatorFound);
5974 if (Result.isInvalid()) {
5975 if (NoArrowOperatorFound) {
5976 if (FirstIteration) {
5977 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
5978 << BaseType << 1 << Base->getSourceRange()
5979 << FixItHint::CreateReplacement(OpLoc, ".");
5980 OpKind = tok::period;
5983 Diag(OpLoc, diag::err_typecheck_member_reference_arrow)
5984 << BaseType << Base->getSourceRange();
5985 CallExpr *CE = dyn_cast<CallExpr>(Base);
5986 if (Decl *CD = (CE ? CE->getCalleeDecl() : nullptr)) {
5987 Diag(CD->getLocStart(),
5988 diag::note_member_reference_arrow_from_operator_arrow);
5993 Base = Result.get();
5994 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base))
5995 OperatorArrows.push_back(OpCall->getDirectCallee());
5996 BaseType = Base->getType();
5997 CanQualType CBaseType = Context.getCanonicalType(BaseType);
5998 if (!CTypes.insert(CBaseType).second) {
5999 Diag(OpLoc, diag::err_operator_arrow_circular) << StartingType;
6000 noteOperatorArrows(*this, OperatorArrows);
6003 FirstIteration = false;
6006 if (OpKind == tok::arrow &&
6007 (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()))
6008 BaseType = BaseType->getPointeeType();
6011 // Objective-C properties allow "." access on Objective-C pointer types,
6012 // so adjust the base type to the object type itself.
6013 if (BaseType->isObjCObjectPointerType())
6014 BaseType = BaseType->getPointeeType();
6016 // C++ [basic.lookup.classref]p2:
6017 // [...] If the type of the object expression is of pointer to scalar
6018 // type, the unqualified-id is looked up in the context of the complete
6019 // postfix-expression.
6021 // This also indicates that we could be parsing a pseudo-destructor-name.
6022 // Note that Objective-C class and object types can be pseudo-destructor
6023 // expressions or normal member (ivar or property) access expressions, and
6024 // it's legal for the type to be incomplete if this is a pseudo-destructor
6025 // call. We'll do more incomplete-type checks later in the lookup process,
6026 // so just skip this check for ObjC types.
6027 if (BaseType->isObjCObjectOrInterfaceType()) {
6028 ObjectType = ParsedType::make(BaseType);
6029 MayBePseudoDestructor = true;
6031 } else if (!BaseType->isRecordType()) {
6032 ObjectType = nullptr;
6033 MayBePseudoDestructor = true;
6037 // The object type must be complete (or dependent), or
6038 // C++11 [expr.prim.general]p3:
6039 // Unlike the object expression in other contexts, *this is not required to
6040 // be of complete type for purposes of class member access (5.2.5) outside
6041 // the member function body.
6042 if (!BaseType->isDependentType() &&
6043 !isThisOutsideMemberFunctionBody(BaseType) &&
6044 RequireCompleteType(OpLoc, BaseType, diag::err_incomplete_member_access))
6047 // C++ [basic.lookup.classref]p2:
6048 // If the id-expression in a class member access (5.2.5) is an
6049 // unqualified-id, and the type of the object expression is of a class
6050 // type C (or of pointer to a class type C), the unqualified-id is looked
6051 // up in the scope of class C. [...]
6052 ObjectType = ParsedType::make(BaseType);
6056 static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base,
6057 tok::TokenKind& OpKind, SourceLocation OpLoc) {
6058 if (Base->hasPlaceholderType()) {
6059 ExprResult result = S.CheckPlaceholderExpr(Base);
6060 if (result.isInvalid()) return true;
6061 Base = result.get();
6063 ObjectType = Base->getType();
6065 // C++ [expr.pseudo]p2:
6066 // The left-hand side of the dot operator shall be of scalar type. The
6067 // left-hand side of the arrow operator shall be of pointer to scalar type.
6068 // This scalar type is the object type.
6069 // Note that this is rather different from the normal handling for the
6071 if (OpKind == tok::arrow) {
6072 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) {
6073 ObjectType = Ptr->getPointeeType();
6074 } else if (!Base->isTypeDependent()) {
6075 // The user wrote "p->" when they probably meant "p."; fix it.
6076 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
6077 << ObjectType << true
6078 << FixItHint::CreateReplacement(OpLoc, ".");
6079 if (S.isSFINAEContext())
6082 OpKind = tok::period;
6089 ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base,
6090 SourceLocation OpLoc,
6091 tok::TokenKind OpKind,
6092 const CXXScopeSpec &SS,
6093 TypeSourceInfo *ScopeTypeInfo,
6094 SourceLocation CCLoc,
6095 SourceLocation TildeLoc,
6096 PseudoDestructorTypeStorage Destructed) {
6097 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo();
6099 QualType ObjectType;
6100 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6103 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() &&
6104 !ObjectType->isVectorType()) {
6105 if (getLangOpts().MSVCCompat && ObjectType->isVoidType())
6106 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange();
6108 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar)
6109 << ObjectType << Base->getSourceRange();
6114 // C++ [expr.pseudo]p2:
6115 // [...] The cv-unqualified versions of the object type and of the type
6116 // designated by the pseudo-destructor-name shall be the same type.
6117 if (DestructedTypeInfo) {
6118 QualType DestructedType = DestructedTypeInfo->getType();
6119 SourceLocation DestructedTypeStart
6120 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin();
6121 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) {
6122 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) {
6123 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch)
6124 << ObjectType << DestructedType << Base->getSourceRange()
6125 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
6127 // Recover by setting the destructed type to the object type.
6128 DestructedType = ObjectType;
6129 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType,
6130 DestructedTypeStart);
6131 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6132 } else if (DestructedType.getObjCLifetime() !=
6133 ObjectType.getObjCLifetime()) {
6135 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) {
6136 // Okay: just pretend that the user provided the correctly-qualified
6139 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals)
6140 << ObjectType << DestructedType << Base->getSourceRange()
6141 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
6144 // Recover by setting the destructed type to the object type.
6145 DestructedType = ObjectType;
6146 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType,
6147 DestructedTypeStart);
6148 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6153 // C++ [expr.pseudo]p2:
6154 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the
6157 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name
6159 // shall designate the same scalar type.
6160 if (ScopeTypeInfo) {
6161 QualType ScopeType = ScopeTypeInfo->getType();
6162 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() &&
6163 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) {
6165 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(),
6166 diag::err_pseudo_dtor_type_mismatch)
6167 << ObjectType << ScopeType << Base->getSourceRange()
6168 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange();
6170 ScopeType = QualType();
6171 ScopeTypeInfo = nullptr;
6176 = new (Context) CXXPseudoDestructorExpr(Context, Base,
6177 OpKind == tok::arrow, OpLoc,
6178 SS.getWithLocInContext(Context),
6187 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
6188 SourceLocation OpLoc,
6189 tok::TokenKind OpKind,
6191 UnqualifiedId &FirstTypeName,
6192 SourceLocation CCLoc,
6193 SourceLocation TildeLoc,
6194 UnqualifiedId &SecondTypeName) {
6195 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
6196 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
6197 "Invalid first type name in pseudo-destructor");
6198 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
6199 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
6200 "Invalid second type name in pseudo-destructor");
6202 QualType ObjectType;
6203 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6206 // Compute the object type that we should use for name lookup purposes. Only
6207 // record types and dependent types matter.
6208 ParsedType ObjectTypePtrForLookup;
6210 if (ObjectType->isRecordType())
6211 ObjectTypePtrForLookup = ParsedType::make(ObjectType);
6212 else if (ObjectType->isDependentType())
6213 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy);
6216 // Convert the name of the type being destructed (following the ~) into a
6217 // type (with source-location information).
6218 QualType DestructedType;
6219 TypeSourceInfo *DestructedTypeInfo = nullptr;
6220 PseudoDestructorTypeStorage Destructed;
6221 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) {
6222 ParsedType T = getTypeName(*SecondTypeName.Identifier,
6223 SecondTypeName.StartLocation,
6224 S, &SS, true, false, ObjectTypePtrForLookup);
6226 ((SS.isSet() && !computeDeclContext(SS, false)) ||
6227 (!SS.isSet() && ObjectType->isDependentType()))) {
6228 // The name of the type being destroyed is a dependent name, and we
6229 // couldn't find anything useful in scope. Just store the identifier and
6230 // it's location, and we'll perform (qualified) name lookup again at
6231 // template instantiation time.
6232 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier,
6233 SecondTypeName.StartLocation);
6235 Diag(SecondTypeName.StartLocation,
6236 diag::err_pseudo_dtor_destructor_non_type)
6237 << SecondTypeName.Identifier << ObjectType;
6238 if (isSFINAEContext())
6241 // Recover by assuming we had the right type all along.
6242 DestructedType = ObjectType;
6244 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo);
6246 // Resolve the template-id to a type.
6247 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId;
6248 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
6249 TemplateId->NumArgs);
6250 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
6251 TemplateId->TemplateKWLoc,
6252 TemplateId->Template,
6253 TemplateId->TemplateNameLoc,
6254 TemplateId->LAngleLoc,
6256 TemplateId->RAngleLoc);
6257 if (T.isInvalid() || !T.get()) {
6258 // Recover by assuming we had the right type all along.
6259 DestructedType = ObjectType;
6261 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo);
6264 // If we've performed some kind of recovery, (re-)build the type source
6266 if (!DestructedType.isNull()) {
6267 if (!DestructedTypeInfo)
6268 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType,
6269 SecondTypeName.StartLocation);
6270 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
6273 // Convert the name of the scope type (the type prior to '::') into a type.
6274 TypeSourceInfo *ScopeTypeInfo = nullptr;
6276 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
6277 FirstTypeName.Identifier) {
6278 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) {
6279 ParsedType T = getTypeName(*FirstTypeName.Identifier,
6280 FirstTypeName.StartLocation,
6281 S, &SS, true, false, ObjectTypePtrForLookup);
6283 Diag(FirstTypeName.StartLocation,
6284 diag::err_pseudo_dtor_destructor_non_type)
6285 << FirstTypeName.Identifier << ObjectType;
6287 if (isSFINAEContext())
6290 // Just drop this type. It's unnecessary anyway.
6291 ScopeType = QualType();
6293 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo);
6295 // Resolve the template-id to a type.
6296 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId;
6297 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
6298 TemplateId->NumArgs);
6299 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
6300 TemplateId->TemplateKWLoc,
6301 TemplateId->Template,
6302 TemplateId->TemplateNameLoc,
6303 TemplateId->LAngleLoc,
6305 TemplateId->RAngleLoc);
6306 if (T.isInvalid() || !T.get()) {
6307 // Recover by dropping this type.
6308 ScopeType = QualType();
6310 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo);
6314 if (!ScopeType.isNull() && !ScopeTypeInfo)
6315 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType,
6316 FirstTypeName.StartLocation);
6319 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS,
6320 ScopeTypeInfo, CCLoc, TildeLoc,
6324 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
6325 SourceLocation OpLoc,
6326 tok::TokenKind OpKind,
6327 SourceLocation TildeLoc,
6328 const DeclSpec& DS) {
6329 QualType ObjectType;
6330 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
6333 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc(),
6337 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T);
6338 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc());
6339 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T);
6340 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo);
6342 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(),
6343 nullptr, SourceLocation(), TildeLoc,
6347 ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl,
6348 CXXConversionDecl *Method,
6349 bool HadMultipleCandidates) {
6350 if (Method->getParent()->isLambda() &&
6351 Method->getConversionType()->isBlockPointerType()) {
6352 // This is a lambda coversion to block pointer; check if the argument
6355 CastExpr *CE = dyn_cast<CastExpr>(SubE);
6356 if (CE && CE->getCastKind() == CK_NoOp)
6357 SubE = CE->getSubExpr();
6358 SubE = SubE->IgnoreParens();
6359 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE))
6360 SubE = BE->getSubExpr();
6361 if (isa<LambdaExpr>(SubE)) {
6362 // For the conversion to block pointer on a lambda expression, we
6363 // construct a special BlockLiteral instead; this doesn't really make
6364 // a difference in ARC, but outside of ARC the resulting block literal
6365 // follows the normal lifetime rules for block literals instead of being
6367 DiagnosticErrorTrap Trap(Diags);
6368 PushExpressionEvaluationContext(PotentiallyEvaluated);
6369 ExprResult Exp = BuildBlockForLambdaConversion(E->getExprLoc(),
6372 PopExpressionEvaluationContext();
6374 if (Exp.isInvalid())
6375 Diag(E->getExprLoc(), diag::note_lambda_to_block_conv);
6380 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/nullptr,
6382 if (Exp.isInvalid())
6385 MemberExpr *ME = new (Context) MemberExpr(
6386 Exp.get(), /*IsArrow=*/false, SourceLocation(), Method, SourceLocation(),
6387 Context.BoundMemberTy, VK_RValue, OK_Ordinary);
6388 if (HadMultipleCandidates)
6389 ME->setHadMultipleCandidates(true);
6390 MarkMemberReferenced(ME);
6392 QualType ResultType = Method->getReturnType();
6393 ExprValueKind VK = Expr::getValueKindForType(ResultType);
6394 ResultType = ResultType.getNonLValueExprType(Context);
6396 CXXMemberCallExpr *CE =
6397 new (Context) CXXMemberCallExpr(Context, ME, None, ResultType, VK,
6398 Exp.get()->getLocEnd());
6402 ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand,
6403 SourceLocation RParen) {
6404 // If the operand is an unresolved lookup expression, the expression is ill-
6405 // formed per [over.over]p1, because overloaded function names cannot be used
6406 // without arguments except in explicit contexts.
6407 ExprResult R = CheckPlaceholderExpr(Operand);
6411 // The operand may have been modified when checking the placeholder type.
6414 if (ActiveTemplateInstantiations.empty() &&
6415 Operand->HasSideEffects(Context, false)) {
6416 // The expression operand for noexcept is in an unevaluated expression
6417 // context, so side effects could result in unintended consequences.
6418 Diag(Operand->getExprLoc(), diag::warn_side_effects_unevaluated_context);
6421 CanThrowResult CanThrow = canThrow(Operand);
6422 return new (Context)
6423 CXXNoexceptExpr(Context.BoolTy, Operand, CanThrow, KeyLoc, RParen);
6426 ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation,
6427 Expr *Operand, SourceLocation RParen) {
6428 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen);
6431 static bool IsSpecialDiscardedValue(Expr *E) {
6432 // In C++11, discarded-value expressions of a certain form are special,
6433 // according to [expr]p10:
6434 // The lvalue-to-rvalue conversion (4.1) is applied only if the
6435 // expression is an lvalue of volatile-qualified type and it has
6436 // one of the following forms:
6437 E = E->IgnoreParens();
6439 // - id-expression (5.1.1),
6440 if (isa<DeclRefExpr>(E))
6443 // - subscripting (5.2.1),
6444 if (isa<ArraySubscriptExpr>(E))
6447 // - class member access (5.2.5),
6448 if (isa<MemberExpr>(E))
6451 // - indirection (5.3.1),
6452 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E))
6453 if (UO->getOpcode() == UO_Deref)
6456 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
6457 // - pointer-to-member operation (5.5),
6458 if (BO->isPtrMemOp())
6461 // - comma expression (5.18) where the right operand is one of the above.
6462 if (BO->getOpcode() == BO_Comma)
6463 return IsSpecialDiscardedValue(BO->getRHS());
6466 // - conditional expression (5.16) where both the second and the third
6467 // operands are one of the above, or
6468 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E))
6469 return IsSpecialDiscardedValue(CO->getTrueExpr()) &&
6470 IsSpecialDiscardedValue(CO->getFalseExpr());
6471 // The related edge case of "*x ?: *x".
6472 if (BinaryConditionalOperator *BCO =
6473 dyn_cast<BinaryConditionalOperator>(E)) {
6474 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(BCO->getTrueExpr()))
6475 return IsSpecialDiscardedValue(OVE->getSourceExpr()) &&
6476 IsSpecialDiscardedValue(BCO->getFalseExpr());
6479 // Objective-C++ extensions to the rule.
6480 if (isa<PseudoObjectExpr>(E) || isa<ObjCIvarRefExpr>(E))
6486 /// Perform the conversions required for an expression used in a
6487 /// context that ignores the result.
6488 ExprResult Sema::IgnoredValueConversions(Expr *E) {
6489 if (E->hasPlaceholderType()) {
6490 ExprResult result = CheckPlaceholderExpr(E);
6491 if (result.isInvalid()) return E;
6496 // [Except in specific positions,] an lvalue that does not have
6497 // array type is converted to the value stored in the
6498 // designated object (and is no longer an lvalue).
6499 if (E->isRValue()) {
6500 // In C, function designators (i.e. expressions of function type)
6501 // are r-values, but we still want to do function-to-pointer decay
6502 // on them. This is both technically correct and convenient for
6504 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType())
6505 return DefaultFunctionArrayConversion(E);
6510 if (getLangOpts().CPlusPlus) {
6511 // The C++11 standard defines the notion of a discarded-value expression;
6512 // normally, we don't need to do anything to handle it, but if it is a
6513 // volatile lvalue with a special form, we perform an lvalue-to-rvalue
6515 if (getLangOpts().CPlusPlus11 && E->isGLValue() &&
6516 E->getType().isVolatileQualified() &&
6517 IsSpecialDiscardedValue(E)) {
6518 ExprResult Res = DefaultLvalueConversion(E);
6519 if (Res.isInvalid())
6526 // GCC seems to also exclude expressions of incomplete enum type.
6527 if (const EnumType *T = E->getType()->getAs<EnumType>()) {
6528 if (!T->getDecl()->isComplete()) {
6529 // FIXME: stupid workaround for a codegen bug!
6530 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).get();
6535 ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
6536 if (Res.isInvalid())
6540 if (!E->getType()->isVoidType())
6541 RequireCompleteType(E->getExprLoc(), E->getType(),
6542 diag::err_incomplete_type);
6546 // If we can unambiguously determine whether Var can never be used
6547 // in a constant expression, return true.
6548 // - if the variable and its initializer are non-dependent, then
6549 // we can unambiguously check if the variable is a constant expression.
6550 // - if the initializer is not value dependent - we can determine whether
6551 // it can be used to initialize a constant expression. If Init can not
6552 // be used to initialize a constant expression we conclude that Var can
6553 // never be a constant expression.
6554 // - FXIME: if the initializer is dependent, we can still do some analysis and
6555 // identify certain cases unambiguously as non-const by using a Visitor:
6556 // - such as those that involve odr-use of a ParmVarDecl, involve a new
6557 // delete, lambda-expr, dynamic-cast, reinterpret-cast etc...
6558 static inline bool VariableCanNeverBeAConstantExpression(VarDecl *Var,
6559 ASTContext &Context) {
6560 if (isa<ParmVarDecl>(Var)) return true;
6561 const VarDecl *DefVD = nullptr;
6563 // If there is no initializer - this can not be a constant expression.
6564 if (!Var->getAnyInitializer(DefVD)) return true;
6566 if (DefVD->isWeak()) return false;
6567 EvaluatedStmt *Eval = DefVD->ensureEvaluatedStmt();
6569 Expr *Init = cast<Expr>(Eval->Value);
6571 if (Var->getType()->isDependentType() || Init->isValueDependent()) {
6572 // FIXME: Teach the constant evaluator to deal with the non-dependent parts
6573 // of value-dependent expressions, and use it here to determine whether the
6574 // initializer is a potential constant expression.
6578 return !IsVariableAConstantExpression(Var, Context);
6581 /// \brief Check if the current lambda has any potential captures
6582 /// that must be captured by any of its enclosing lambdas that are ready to
6583 /// capture. If there is a lambda that can capture a nested
6584 /// potential-capture, go ahead and do so. Also, check to see if any
6585 /// variables are uncaptureable or do not involve an odr-use so do not
6586 /// need to be captured.
6588 static void CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(
6589 Expr *const FE, LambdaScopeInfo *const CurrentLSI, Sema &S) {
6591 assert(!S.isUnevaluatedContext());
6592 assert(S.CurContext->isDependentContext());
6594 DeclContext *DC = S.CurContext;
6595 while (DC && isa<CapturedDecl>(DC))
6596 DC = DC->getParent();
6598 CurrentLSI->CallOperator == DC &&
6599 "The current call operator must be synchronized with Sema's CurContext");
6602 const bool IsFullExprInstantiationDependent = FE->isInstantiationDependent();
6604 ArrayRef<const FunctionScopeInfo *> FunctionScopesArrayRef(
6605 S.FunctionScopes.data(), S.FunctionScopes.size());
6607 // All the potentially captureable variables in the current nested
6608 // lambda (within a generic outer lambda), must be captured by an
6609 // outer lambda that is enclosed within a non-dependent context.
6610 const unsigned NumPotentialCaptures =
6611 CurrentLSI->getNumPotentialVariableCaptures();
6612 for (unsigned I = 0; I != NumPotentialCaptures; ++I) {
6613 Expr *VarExpr = nullptr;
6614 VarDecl *Var = nullptr;
6615 CurrentLSI->getPotentialVariableCapture(I, Var, VarExpr);
6616 // If the variable is clearly identified as non-odr-used and the full
6617 // expression is not instantiation dependent, only then do we not
6618 // need to check enclosing lambda's for speculative captures.
6620 // Even though 'x' is not odr-used, it should be captured.
6622 // const int x = 10;
6623 // auto L = [=](auto a) {
6627 if (CurrentLSI->isVariableExprMarkedAsNonODRUsed(VarExpr) &&
6628 !IsFullExprInstantiationDependent)
6631 // If we have a capture-capable lambda for the variable, go ahead and
6632 // capture the variable in that lambda (and all its enclosing lambdas).
6633 if (const Optional<unsigned> Index =
6634 getStackIndexOfNearestEnclosingCaptureCapableLambda(
6635 FunctionScopesArrayRef, Var, S)) {
6636 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
6637 MarkVarDeclODRUsed(Var, VarExpr->getExprLoc(), S,
6638 &FunctionScopeIndexOfCapturableLambda);
6640 const bool IsVarNeverAConstantExpression =
6641 VariableCanNeverBeAConstantExpression(Var, S.Context);
6642 if (!IsFullExprInstantiationDependent || IsVarNeverAConstantExpression) {
6643 // This full expression is not instantiation dependent or the variable
6644 // can not be used in a constant expression - which means
6645 // this variable must be odr-used here, so diagnose a
6646 // capture violation early, if the variable is un-captureable.
6647 // This is purely for diagnosing errors early. Otherwise, this
6648 // error would get diagnosed when the lambda becomes capture ready.
6649 QualType CaptureType, DeclRefType;
6650 SourceLocation ExprLoc = VarExpr->getExprLoc();
6651 if (S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
6652 /*EllipsisLoc*/ SourceLocation(),
6653 /*BuildAndDiagnose*/false, CaptureType,
6654 DeclRefType, nullptr)) {
6655 // We will never be able to capture this variable, and we need
6656 // to be able to in any and all instantiations, so diagnose it.
6657 S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
6658 /*EllipsisLoc*/ SourceLocation(),
6659 /*BuildAndDiagnose*/true, CaptureType,
6660 DeclRefType, nullptr);
6665 // Check if 'this' needs to be captured.
6666 if (CurrentLSI->hasPotentialThisCapture()) {
6667 // If we have a capture-capable lambda for 'this', go ahead and capture
6668 // 'this' in that lambda (and all its enclosing lambdas).
6669 if (const Optional<unsigned> Index =
6670 getStackIndexOfNearestEnclosingCaptureCapableLambda(
6671 FunctionScopesArrayRef, /*0 is 'this'*/ nullptr, S)) {
6672 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
6673 S.CheckCXXThisCapture(CurrentLSI->PotentialThisCaptureLocation,
6674 /*Explicit*/ false, /*BuildAndDiagnose*/ true,
6675 &FunctionScopeIndexOfCapturableLambda);
6679 // Reset all the potential captures at the end of each full-expression.
6680 CurrentLSI->clearPotentialCaptures();
6683 static ExprResult attemptRecovery(Sema &SemaRef,
6684 const TypoCorrectionConsumer &Consumer,
6685 const TypoCorrection &TC) {
6686 LookupResult R(SemaRef, Consumer.getLookupResult().getLookupNameInfo(),
6687 Consumer.getLookupResult().getLookupKind());
6688 const CXXScopeSpec *SS = Consumer.getSS();
6691 // Use an approprate CXXScopeSpec for building the expr.
6692 if (auto *NNS = TC.getCorrectionSpecifier())
6693 NewSS.MakeTrivial(SemaRef.Context, NNS, TC.getCorrectionRange());
6694 else if (SS && !TC.WillReplaceSpecifier())
6697 if (auto *ND = TC.getFoundDecl()) {
6698 R.setLookupName(ND->getDeclName());
6700 if (ND->isCXXClassMember()) {
6701 // Figure out the correct naming class to add to the LookupResult.
6702 CXXRecordDecl *Record = nullptr;
6703 if (auto *NNS = TC.getCorrectionSpecifier())
6704 Record = NNS->getAsType()->getAsCXXRecordDecl();
6707 dyn_cast<CXXRecordDecl>(ND->getDeclContext()->getRedeclContext());
6709 R.setNamingClass(Record);
6711 // Detect and handle the case where the decl might be an implicit
6713 bool MightBeImplicitMember;
6714 if (!Consumer.isAddressOfOperand())
6715 MightBeImplicitMember = true;
6716 else if (!NewSS.isEmpty())
6717 MightBeImplicitMember = false;
6718 else if (R.isOverloadedResult())
6719 MightBeImplicitMember = false;
6720 else if (R.isUnresolvableResult())
6721 MightBeImplicitMember = true;
6723 MightBeImplicitMember = isa<FieldDecl>(ND) ||
6724 isa<IndirectFieldDecl>(ND) ||
6725 isa<MSPropertyDecl>(ND);
6727 if (MightBeImplicitMember)
6728 return SemaRef.BuildPossibleImplicitMemberExpr(
6729 NewSS, /*TemplateKWLoc*/ SourceLocation(), R,
6730 /*TemplateArgs*/ nullptr, /*S*/ nullptr);
6731 } else if (auto *Ivar = dyn_cast<ObjCIvarDecl>(ND)) {
6732 return SemaRef.LookupInObjCMethod(R, Consumer.getScope(),
6733 Ivar->getIdentifier());
6737 return SemaRef.BuildDeclarationNameExpr(NewSS, R, /*NeedsADL*/ false,
6738 /*AcceptInvalidDecl*/ true);
6742 class FindTypoExprs : public RecursiveASTVisitor<FindTypoExprs> {
6743 llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs;
6746 explicit FindTypoExprs(llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs)
6747 : TypoExprs(TypoExprs) {}
6748 bool VisitTypoExpr(TypoExpr *TE) {
6749 TypoExprs.insert(TE);
6754 class TransformTypos : public TreeTransform<TransformTypos> {
6755 typedef TreeTransform<TransformTypos> BaseTransform;
6757 VarDecl *InitDecl; // A decl to avoid as a correction because it is in the
6758 // process of being initialized.
6759 llvm::function_ref<ExprResult(Expr *)> ExprFilter;
6760 llvm::SmallSetVector<TypoExpr *, 2> TypoExprs, AmbiguousTypoExprs;
6761 llvm::SmallDenseMap<TypoExpr *, ExprResult, 2> TransformCache;
6762 llvm::SmallDenseMap<OverloadExpr *, Expr *, 4> OverloadResolution;
6764 /// \brief Emit diagnostics for all of the TypoExprs encountered.
6765 /// If the TypoExprs were successfully corrected, then the diagnostics should
6766 /// suggest the corrections. Otherwise the diagnostics will not suggest
6767 /// anything (having been passed an empty TypoCorrection).
6768 void EmitAllDiagnostics() {
6769 for (auto E : TypoExprs) {
6770 TypoExpr *TE = cast<TypoExpr>(E);
6771 auto &State = SemaRef.getTypoExprState(TE);
6772 if (State.DiagHandler) {
6773 TypoCorrection TC = State.Consumer->getCurrentCorrection();
6774 ExprResult Replacement = TransformCache[TE];
6776 // Extract the NamedDecl from the transformed TypoExpr and add it to the
6777 // TypoCorrection, replacing the existing decls. This ensures the right
6778 // NamedDecl is used in diagnostics e.g. in the case where overload
6779 // resolution was used to select one from several possible decls that
6780 // had been stored in the TypoCorrection.
6781 if (auto *ND = getDeclFromExpr(
6782 Replacement.isInvalid() ? nullptr : Replacement.get()))
6783 TC.setCorrectionDecl(ND);
6785 State.DiagHandler(TC);
6787 SemaRef.clearDelayedTypo(TE);
6791 /// \brief If corrections for the first TypoExpr have been exhausted for a
6792 /// given combination of the other TypoExprs, retry those corrections against
6793 /// the next combination of substitutions for the other TypoExprs by advancing
6794 /// to the next potential correction of the second TypoExpr. For the second
6795 /// and subsequent TypoExprs, if its stream of corrections has been exhausted,
6796 /// the stream is reset and the next TypoExpr's stream is advanced by one (a
6797 /// TypoExpr's correction stream is advanced by removing the TypoExpr from the
6798 /// TransformCache). Returns true if there is still any untried combinations
6800 bool CheckAndAdvanceTypoExprCorrectionStreams() {
6801 for (auto TE : TypoExprs) {
6802 auto &State = SemaRef.getTypoExprState(TE);
6803 TransformCache.erase(TE);
6804 if (!State.Consumer->finished())
6806 State.Consumer->resetCorrectionStream();
6811 NamedDecl *getDeclFromExpr(Expr *E) {
6812 if (auto *OE = dyn_cast_or_null<OverloadExpr>(E))
6813 E = OverloadResolution[OE];
6817 if (auto *DRE = dyn_cast<DeclRefExpr>(E))
6818 return DRE->getFoundDecl();
6819 if (auto *ME = dyn_cast<MemberExpr>(E))
6820 return ME->getFoundDecl();
6821 // FIXME: Add any other expr types that could be be seen by the delayed typo
6822 // correction TreeTransform for which the corresponding TypoCorrection could
6823 // contain multiple decls.
6827 ExprResult TryTransform(Expr *E) {
6828 Sema::SFINAETrap Trap(SemaRef);
6829 ExprResult Res = TransformExpr(E);
6830 if (Trap.hasErrorOccurred() || Res.isInvalid())
6833 return ExprFilter(Res.get());
6837 TransformTypos(Sema &SemaRef, VarDecl *InitDecl, llvm::function_ref<ExprResult(Expr *)> Filter)
6838 : BaseTransform(SemaRef), InitDecl(InitDecl), ExprFilter(Filter) {}
6840 ExprResult RebuildCallExpr(Expr *Callee, SourceLocation LParenLoc,
6842 SourceLocation RParenLoc,
6843 Expr *ExecConfig = nullptr) {
6844 auto Result = BaseTransform::RebuildCallExpr(Callee, LParenLoc, Args,
6845 RParenLoc, ExecConfig);
6846 if (auto *OE = dyn_cast<OverloadExpr>(Callee)) {
6847 if (Result.isUsable()) {
6848 Expr *ResultCall = Result.get();
6849 if (auto *BE = dyn_cast<CXXBindTemporaryExpr>(ResultCall))
6850 ResultCall = BE->getSubExpr();
6851 if (auto *CE = dyn_cast<CallExpr>(ResultCall))
6852 OverloadResolution[OE] = CE->getCallee();
6858 ExprResult TransformLambdaExpr(LambdaExpr *E) { return Owned(E); }
6860 ExprResult TransformBlockExpr(BlockExpr *E) { return Owned(E); }
6862 ExprResult TransformObjCPropertyRefExpr(ObjCPropertyRefExpr *E) {
6866 ExprResult TransformObjCIvarRefExpr(ObjCIvarRefExpr *E) {
6870 ExprResult Transform(Expr *E) {
6873 Res = TryTransform(E);
6875 // Exit if either the transform was valid or if there were no TypoExprs
6876 // to transform that still have any untried correction candidates..
6877 if (!Res.isInvalid() ||
6878 !CheckAndAdvanceTypoExprCorrectionStreams())
6882 // Ensure none of the TypoExprs have multiple typo correction candidates
6883 // with the same edit length that pass all the checks and filters.
6884 // TODO: Properly handle various permutations of possible corrections when
6885 // there is more than one potentially ambiguous typo correction.
6886 // Also, disable typo correction while attempting the transform when
6887 // handling potentially ambiguous typo corrections as any new TypoExprs will
6888 // have been introduced by the application of one of the correction
6889 // candidates and add little to no value if corrected.
6890 SemaRef.DisableTypoCorrection = true;
6891 while (!AmbiguousTypoExprs.empty()) {
6892 auto TE = AmbiguousTypoExprs.back();
6893 auto Cached = TransformCache[TE];
6894 auto &State = SemaRef.getTypoExprState(TE);
6895 State.Consumer->saveCurrentPosition();
6896 TransformCache.erase(TE);
6897 if (!TryTransform(E).isInvalid()) {
6898 State.Consumer->resetCorrectionStream();
6899 TransformCache.erase(TE);
6903 AmbiguousTypoExprs.remove(TE);
6904 State.Consumer->restoreSavedPosition();
6905 TransformCache[TE] = Cached;
6907 SemaRef.DisableTypoCorrection = false;
6909 // Ensure that all of the TypoExprs within the current Expr have been found.
6910 if (!Res.isUsable())
6911 FindTypoExprs(TypoExprs).TraverseStmt(E);
6913 EmitAllDiagnostics();
6918 ExprResult TransformTypoExpr(TypoExpr *E) {
6919 // If the TypoExpr hasn't been seen before, record it. Otherwise, return the
6920 // cached transformation result if there is one and the TypoExpr isn't the
6921 // first one that was encountered.
6922 auto &CacheEntry = TransformCache[E];
6923 if (!TypoExprs.insert(E) && !CacheEntry.isUnset()) {
6927 auto &State = SemaRef.getTypoExprState(E);
6928 assert(State.Consumer && "Cannot transform a cleared TypoExpr");
6930 // For the first TypoExpr and an uncached TypoExpr, find the next likely
6931 // typo correction and return it.
6932 while (TypoCorrection TC = State.Consumer->getNextCorrection()) {
6933 if (InitDecl && TC.getFoundDecl() == InitDecl)
6935 ExprResult NE = State.RecoveryHandler ?
6936 State.RecoveryHandler(SemaRef, E, TC) :
6937 attemptRecovery(SemaRef, *State.Consumer, TC);
6938 if (!NE.isInvalid()) {
6939 // Check whether there may be a second viable correction with the same
6940 // edit distance; if so, remember this TypoExpr may have an ambiguous
6941 // correction so it can be more thoroughly vetted later.
6942 TypoCorrection Next;
6943 if ((Next = State.Consumer->peekNextCorrection()) &&
6944 Next.getEditDistance(false) == TC.getEditDistance(false)) {
6945 AmbiguousTypoExprs.insert(E);
6947 AmbiguousTypoExprs.remove(E);
6949 assert(!NE.isUnset() &&
6950 "Typo was transformed into a valid-but-null ExprResult");
6951 return CacheEntry = NE;
6954 return CacheEntry = ExprError();
6960 Sema::CorrectDelayedTyposInExpr(Expr *E, VarDecl *InitDecl,
6961 llvm::function_ref<ExprResult(Expr *)> Filter) {
6962 // If the current evaluation context indicates there are uncorrected typos
6963 // and the current expression isn't guaranteed to not have typos, try to
6964 // resolve any TypoExpr nodes that might be in the expression.
6965 if (E && !ExprEvalContexts.empty() && ExprEvalContexts.back().NumTypos &&
6966 (E->isTypeDependent() || E->isValueDependent() ||
6967 E->isInstantiationDependent())) {
6968 auto TyposInContext = ExprEvalContexts.back().NumTypos;
6969 assert(TyposInContext < ~0U && "Recursive call of CorrectDelayedTyposInExpr");
6970 ExprEvalContexts.back().NumTypos = ~0U;
6971 auto TyposResolved = DelayedTypos.size();
6972 auto Result = TransformTypos(*this, InitDecl, Filter).Transform(E);
6973 ExprEvalContexts.back().NumTypos = TyposInContext;
6974 TyposResolved -= DelayedTypos.size();
6975 if (Result.isInvalid() || Result.get() != E) {
6976 ExprEvalContexts.back().NumTypos -= TyposResolved;
6979 assert(TyposResolved == 0 && "Corrected typo but got same Expr back?");
6984 ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC,
6985 bool DiscardedValue,
6987 bool IsLambdaInitCaptureInitializer) {
6988 ExprResult FullExpr = FE;
6990 if (!FullExpr.get())
6993 // If we are an init-expression in a lambdas init-capture, we should not
6994 // diagnose an unexpanded pack now (will be diagnosed once lambda-expr
6995 // containing full-expression is done).
6996 // template<class ... Ts> void test(Ts ... t) {
6997 // test([&a(t)]() { <-- (t) is an init-expr that shouldn't be diagnosed now.
7001 // FIXME: This is a hack. It would be better if we pushed the lambda scope
7002 // when we parse the lambda introducer, and teach capturing (but not
7003 // unexpanded pack detection) to walk over LambdaScopeInfos which don't have a
7004 // corresponding class yet (that is, have LambdaScopeInfo either represent a
7005 // lambda where we've entered the introducer but not the body, or represent a
7006 // lambda where we've entered the body, depending on where the
7007 // parser/instantiation has got to).
7008 if (!IsLambdaInitCaptureInitializer &&
7009 DiagnoseUnexpandedParameterPack(FullExpr.get()))
7012 // Top-level expressions default to 'id' when we're in a debugger.
7013 if (DiscardedValue && getLangOpts().DebuggerCastResultToId &&
7014 FullExpr.get()->getType() == Context.UnknownAnyTy) {
7015 FullExpr = forceUnknownAnyToType(FullExpr.get(), Context.getObjCIdType());
7016 if (FullExpr.isInvalid())
7020 if (DiscardedValue) {
7021 FullExpr = CheckPlaceholderExpr(FullExpr.get());
7022 if (FullExpr.isInvalid())
7025 FullExpr = IgnoredValueConversions(FullExpr.get());
7026 if (FullExpr.isInvalid())
7030 FullExpr = CorrectDelayedTyposInExpr(FullExpr.get());
7031 if (FullExpr.isInvalid())
7034 CheckCompletedExpr(FullExpr.get(), CC, IsConstexpr);
7036 // At the end of this full expression (which could be a deeply nested
7037 // lambda), if there is a potential capture within the nested lambda,
7038 // have the outer capture-able lambda try and capture it.
7039 // Consider the following code:
7040 // void f(int, int);
7041 // void f(const int&, double);
7043 // const int x = 10, y = 20;
7044 // auto L = [=](auto a) {
7045 // auto M = [=](auto b) {
7046 // f(x, b); <-- requires x to be captured by L and M
7047 // f(y, a); <-- requires y to be captured by L, but not all Ms
7052 // FIXME: Also consider what happens for something like this that involves
7053 // the gnu-extension statement-expressions or even lambda-init-captures:
7056 // auto L = [&](auto a) {
7057 // +n + ({ 0; a; });
7061 // Here, we see +n, and then the full-expression 0; ends, so we don't
7062 // capture n (and instead remove it from our list of potential captures),
7063 // and then the full-expression +n + ({ 0; }); ends, but it's too late
7064 // for us to see that we need to capture n after all.
7066 LambdaScopeInfo *const CurrentLSI =
7067 getCurLambda(/*IgnoreCapturedRegions=*/true);
7068 // FIXME: PR 17877 showed that getCurLambda() can return a valid pointer
7069 // even if CurContext is not a lambda call operator. Refer to that Bug Report
7070 // for an example of the code that might cause this asynchrony.
7071 // By ensuring we are in the context of a lambda's call operator
7072 // we can fix the bug (we only need to check whether we need to capture
7073 // if we are within a lambda's body); but per the comments in that
7074 // PR, a proper fix would entail :
7075 // "Alternative suggestion:
7076 // - Add to Sema an integer holding the smallest (outermost) scope
7077 // index that we are *lexically* within, and save/restore/set to
7078 // FunctionScopes.size() in InstantiatingTemplate's
7079 // constructor/destructor.
7080 // - Teach the handful of places that iterate over FunctionScopes to
7081 // stop at the outermost enclosing lexical scope."
7082 DeclContext *DC = CurContext;
7083 while (DC && isa<CapturedDecl>(DC))
7084 DC = DC->getParent();
7085 const bool IsInLambdaDeclContext = isLambdaCallOperator(DC);
7086 if (IsInLambdaDeclContext && CurrentLSI &&
7087 CurrentLSI->hasPotentialCaptures() && !FullExpr.isInvalid())
7088 CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(FE, CurrentLSI,
7090 return MaybeCreateExprWithCleanups(FullExpr);
7093 StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) {
7094 if (!FullStmt) return StmtError();
7096 return MaybeCreateStmtWithCleanups(FullStmt);
7099 Sema::IfExistsResult
7100 Sema::CheckMicrosoftIfExistsSymbol(Scope *S,
7102 const DeclarationNameInfo &TargetNameInfo) {
7103 DeclarationName TargetName = TargetNameInfo.getName();
7105 return IER_DoesNotExist;
7107 // If the name itself is dependent, then the result is dependent.
7108 if (TargetName.isDependentName())
7109 return IER_Dependent;
7111 // Do the redeclaration lookup in the current scope.
7112 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName,
7113 Sema::NotForRedeclaration);
7114 LookupParsedName(R, S, &SS);
7115 R.suppressDiagnostics();
7117 switch (R.getResultKind()) {
7118 case LookupResult::Found:
7119 case LookupResult::FoundOverloaded:
7120 case LookupResult::FoundUnresolvedValue:
7121 case LookupResult::Ambiguous:
7124 case LookupResult::NotFound:
7125 return IER_DoesNotExist;
7127 case LookupResult::NotFoundInCurrentInstantiation:
7128 return IER_Dependent;
7131 llvm_unreachable("Invalid LookupResult Kind!");
7134 Sema::IfExistsResult
7135 Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc,
7136 bool IsIfExists, CXXScopeSpec &SS,
7137 UnqualifiedId &Name) {
7138 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
7140 // Check for unexpanded parameter packs.
7141 SmallVector<UnexpandedParameterPack, 4> Unexpanded;
7142 collectUnexpandedParameterPacks(SS, Unexpanded);
7143 collectUnexpandedParameterPacks(TargetNameInfo, Unexpanded);
7144 if (!Unexpanded.empty()) {
7145 DiagnoseUnexpandedParameterPacks(KeywordLoc,
7146 IsIfExists? UPPC_IfExists
7152 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo);