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 /// \brief Build a Microsoft __uuidof expression with a type operand.
512 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType,
513 SourceLocation TypeidLoc,
514 TypeSourceInfo *Operand,
515 SourceLocation RParenLoc) {
516 if (!Operand->getType()->isDependentType()) {
517 bool HasMultipleGUIDs = false;
518 if (!CXXUuidofExpr::GetUuidAttrOfType(Operand->getType(),
519 &HasMultipleGUIDs)) {
520 if (HasMultipleGUIDs)
521 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
523 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
527 return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), Operand,
528 SourceRange(TypeidLoc, RParenLoc));
531 /// \brief Build a Microsoft __uuidof expression with an expression operand.
532 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType,
533 SourceLocation TypeidLoc,
535 SourceLocation RParenLoc) {
536 if (!E->getType()->isDependentType()) {
537 bool HasMultipleGUIDs = false;
538 if (!CXXUuidofExpr::GetUuidAttrOfType(E->getType(), &HasMultipleGUIDs) &&
539 !E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
540 if (HasMultipleGUIDs)
541 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
543 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
547 return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), E,
548 SourceRange(TypeidLoc, RParenLoc));
551 /// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression);
553 Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc,
554 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
555 // If MSVCGuidDecl has not been cached, do the lookup.
557 IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID");
558 LookupResult R(*this, GuidII, SourceLocation(), LookupTagName);
559 LookupQualifiedName(R, Context.getTranslationUnitDecl());
560 MSVCGuidDecl = R.getAsSingle<RecordDecl>();
562 return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof));
565 QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl);
568 // The operand is a type; handle it as such.
569 TypeSourceInfo *TInfo = nullptr;
570 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
576 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
578 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc);
581 // The operand is an expression.
582 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
585 /// ActOnCXXBoolLiteral - Parse {true,false} literals.
587 Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
588 assert((Kind == tok::kw_true || Kind == tok::kw_false) &&
589 "Unknown C++ Boolean value!");
591 CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc);
594 /// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
596 Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) {
597 return new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
600 /// ActOnCXXThrow - Parse throw expressions.
602 Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) {
603 bool IsThrownVarInScope = false;
605 // C++0x [class.copymove]p31:
606 // When certain criteria are met, an implementation is allowed to omit the
607 // copy/move construction of a class object [...]
609 // - in a throw-expression, when the operand is the name of a
610 // non-volatile automatic object (other than a function or catch-
611 // clause parameter) whose scope does not extend beyond the end of the
612 // innermost enclosing try-block (if there is one), the copy/move
613 // operation from the operand to the exception object (15.1) can be
614 // omitted by constructing the automatic object directly into the
616 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens()))
617 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
618 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) {
619 for( ; S; S = S->getParent()) {
620 if (S->isDeclScope(Var)) {
621 IsThrownVarInScope = true;
626 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope |
627 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope |
635 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope);
638 ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex,
639 bool IsThrownVarInScope) {
640 // Don't report an error if 'throw' is used in system headers.
641 if (!getLangOpts().CXXExceptions &&
642 !getSourceManager().isInSystemHeader(OpLoc))
643 Diag(OpLoc, diag::err_exceptions_disabled) << "throw";
645 if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
646 Diag(OpLoc, diag::err_omp_simd_region_cannot_use_stmt) << "throw";
648 if (Ex && !Ex->isTypeDependent()) {
649 QualType ExceptionObjectTy = Context.getExceptionObjectType(Ex->getType());
650 if (CheckCXXThrowOperand(OpLoc, ExceptionObjectTy, Ex))
653 // Initialize the exception result. This implicitly weeds out
654 // abstract types or types with inaccessible copy constructors.
656 // C++0x [class.copymove]p31:
657 // When certain criteria are met, an implementation is allowed to omit the
658 // copy/move construction of a class object [...]
660 // - in a throw-expression, when the operand is the name of a
661 // non-volatile automatic object (other than a function or
663 // parameter) whose scope does not extend beyond the end of the
664 // innermost enclosing try-block (if there is one), the copy/move
665 // operation from the operand to the exception object (15.1) can be
666 // omitted by constructing the automatic object directly into the
668 const VarDecl *NRVOVariable = nullptr;
669 if (IsThrownVarInScope)
670 NRVOVariable = getCopyElisionCandidate(QualType(), Ex, false);
672 InitializedEntity Entity = InitializedEntity::InitializeException(
673 OpLoc, ExceptionObjectTy,
674 /*NRVO=*/NRVOVariable != nullptr);
675 ExprResult Res = PerformMoveOrCopyInitialization(
676 Entity, NRVOVariable, QualType(), Ex, IsThrownVarInScope);
683 CXXThrowExpr(Ex, Context.VoidTy, OpLoc, IsThrownVarInScope);
687 collectPublicBases(CXXRecordDecl *RD,
688 llvm::DenseMap<CXXRecordDecl *, unsigned> &SubobjectsSeen,
689 llvm::SmallPtrSetImpl<CXXRecordDecl *> &VBases,
690 llvm::SetVector<CXXRecordDecl *> &PublicSubobjectsSeen,
691 bool ParentIsPublic) {
692 for (const CXXBaseSpecifier &BS : RD->bases()) {
693 CXXRecordDecl *BaseDecl = BS.getType()->getAsCXXRecordDecl();
695 // Virtual bases constitute the same subobject. Non-virtual bases are
696 // always distinct subobjects.
698 NewSubobject = VBases.insert(BaseDecl).second;
703 ++SubobjectsSeen[BaseDecl];
705 // Only add subobjects which have public access throughout the entire chain.
706 bool PublicPath = ParentIsPublic && BS.getAccessSpecifier() == AS_public;
708 PublicSubobjectsSeen.insert(BaseDecl);
710 // Recurse on to each base subobject.
711 collectPublicBases(BaseDecl, SubobjectsSeen, VBases, PublicSubobjectsSeen,
716 static void getUnambiguousPublicSubobjects(
717 CXXRecordDecl *RD, llvm::SmallVectorImpl<CXXRecordDecl *> &Objects) {
718 llvm::DenseMap<CXXRecordDecl *, unsigned> SubobjectsSeen;
719 llvm::SmallSet<CXXRecordDecl *, 2> VBases;
720 llvm::SetVector<CXXRecordDecl *> PublicSubobjectsSeen;
721 SubobjectsSeen[RD] = 1;
722 PublicSubobjectsSeen.insert(RD);
723 collectPublicBases(RD, SubobjectsSeen, VBases, PublicSubobjectsSeen,
724 /*ParentIsPublic=*/true);
726 for (CXXRecordDecl *PublicSubobject : PublicSubobjectsSeen) {
727 // Skip ambiguous objects.
728 if (SubobjectsSeen[PublicSubobject] > 1)
731 Objects.push_back(PublicSubobject);
735 /// CheckCXXThrowOperand - Validate the operand of a throw.
736 bool Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc,
737 QualType ExceptionObjectTy, Expr *E) {
738 // If the type of the exception would be an incomplete type or a pointer
739 // to an incomplete type other than (cv) void the program is ill-formed.
740 QualType Ty = ExceptionObjectTy;
741 bool isPointer = false;
742 if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
743 Ty = Ptr->getPointeeType();
746 if (!isPointer || !Ty->isVoidType()) {
747 if (RequireCompleteType(ThrowLoc, Ty,
748 isPointer ? diag::err_throw_incomplete_ptr
749 : diag::err_throw_incomplete,
750 E->getSourceRange()))
753 if (RequireNonAbstractType(ThrowLoc, ExceptionObjectTy,
754 diag::err_throw_abstract_type, E))
758 // If the exception has class type, we need additional handling.
759 CXXRecordDecl *RD = Ty->getAsCXXRecordDecl();
763 // If we are throwing a polymorphic class type or pointer thereof,
764 // exception handling will make use of the vtable.
765 MarkVTableUsed(ThrowLoc, RD);
767 // If a pointer is thrown, the referenced object will not be destroyed.
771 // If the class has a destructor, we must be able to call it.
772 if (!RD->hasIrrelevantDestructor()) {
773 if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
774 MarkFunctionReferenced(E->getExprLoc(), Destructor);
775 CheckDestructorAccess(E->getExprLoc(), Destructor,
776 PDiag(diag::err_access_dtor_exception) << Ty);
777 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
782 // The MSVC ABI creates a list of all types which can catch the exception
783 // object. This list also references the appropriate copy constructor to call
784 // if the object is caught by value and has a non-trivial copy constructor.
785 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
786 // We are only interested in the public, unambiguous bases contained within
787 // the exception object. Bases which are ambiguous or otherwise
788 // inaccessible are not catchable types.
789 llvm::SmallVector<CXXRecordDecl *, 2> UnambiguousPublicSubobjects;
790 getUnambiguousPublicSubobjects(RD, UnambiguousPublicSubobjects);
792 for (CXXRecordDecl *Subobject : UnambiguousPublicSubobjects) {
793 // Attempt to lookup the copy constructor. Various pieces of machinery
794 // will spring into action, like template instantiation, which means this
795 // cannot be a simple walk of the class's decls. Instead, we must perform
796 // lookup and overload resolution.
797 CXXConstructorDecl *CD = LookupCopyingConstructor(Subobject, 0);
801 // Mark the constructor referenced as it is used by this throw expression.
802 MarkFunctionReferenced(E->getExprLoc(), CD);
804 // Skip this copy constructor if it is trivial, we don't need to record it
805 // in the catchable type data.
809 // The copy constructor is non-trivial, create a mapping from this class
810 // type to this constructor.
811 // N.B. The selection of copy constructor is not sensitive to this
812 // particular throw-site. Lookup will be performed at the catch-site to
813 // ensure that the copy constructor is, in fact, accessible (via
814 // friendship or any other means).
815 Context.addCopyConstructorForExceptionObject(Subobject, CD);
817 // We don't keep the instantiated default argument expressions around so
818 // we must rebuild them here.
819 for (unsigned I = 1, E = CD->getNumParams(); I != E; ++I) {
820 // Skip any default arguments that we've already instantiated.
821 if (Context.getDefaultArgExprForConstructor(CD, I))
825 BuildCXXDefaultArgExpr(ThrowLoc, CD, CD->getParamDecl(I)).get();
826 Context.addDefaultArgExprForConstructor(CD, I, DefaultArg);
834 QualType Sema::getCurrentThisType() {
835 DeclContext *DC = getFunctionLevelDeclContext();
836 QualType ThisTy = CXXThisTypeOverride;
837 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) {
838 if (method && method->isInstance())
839 ThisTy = method->getThisType(Context);
841 if (ThisTy.isNull()) {
842 if (isGenericLambdaCallOperatorSpecialization(CurContext) &&
843 CurContext->getParent()->getParent()->isRecord()) {
844 // This is a generic lambda call operator that is being instantiated
845 // within a default initializer - so use the enclosing class as 'this'.
846 // There is no enclosing member function to retrieve the 'this' pointer
848 QualType ClassTy = Context.getTypeDeclType(
849 cast<CXXRecordDecl>(CurContext->getParent()->getParent()));
850 // There are no cv-qualifiers for 'this' within default initializers,
851 // per [expr.prim.general]p4.
852 return Context.getPointerType(ClassTy);
858 Sema::CXXThisScopeRAII::CXXThisScopeRAII(Sema &S,
860 unsigned CXXThisTypeQuals,
862 : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false)
864 if (!Enabled || !ContextDecl)
867 CXXRecordDecl *Record = nullptr;
868 if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl))
869 Record = Template->getTemplatedDecl();
871 Record = cast<CXXRecordDecl>(ContextDecl);
873 S.CXXThisTypeOverride
874 = S.Context.getPointerType(
875 S.Context.getRecordType(Record).withCVRQualifiers(CXXThisTypeQuals));
877 this->Enabled = true;
881 Sema::CXXThisScopeRAII::~CXXThisScopeRAII() {
883 S.CXXThisTypeOverride = OldCXXThisTypeOverride;
887 static Expr *captureThis(ASTContext &Context, RecordDecl *RD,
888 QualType ThisTy, SourceLocation Loc) {
890 = FieldDecl::Create(Context, RD, Loc, Loc, nullptr, ThisTy,
891 Context.getTrivialTypeSourceInfo(ThisTy, Loc),
892 nullptr, false, ICIS_NoInit);
893 Field->setImplicit(true);
894 Field->setAccess(AS_private);
896 return new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit*/true);
899 bool Sema::CheckCXXThisCapture(SourceLocation Loc, bool Explicit,
900 bool BuildAndDiagnose, const unsigned *const FunctionScopeIndexToStopAt) {
901 // We don't need to capture this in an unevaluated context.
902 if (isUnevaluatedContext() && !Explicit)
905 const unsigned MaxFunctionScopesIndex = FunctionScopeIndexToStopAt ?
906 *FunctionScopeIndexToStopAt : FunctionScopes.size() - 1;
907 // Otherwise, check that we can capture 'this'.
908 unsigned NumClosures = 0;
909 for (unsigned idx = MaxFunctionScopesIndex; idx != 0; idx--) {
910 if (CapturingScopeInfo *CSI =
911 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) {
912 if (CSI->CXXThisCaptureIndex != 0) {
913 // 'this' is already being captured; there isn't anything more to do.
916 LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI);
917 if (LSI && isGenericLambdaCallOperatorSpecialization(LSI->CallOperator)) {
918 // This context can't implicitly capture 'this'; fail out.
919 if (BuildAndDiagnose)
920 Diag(Loc, diag::err_this_capture) << Explicit;
923 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref ||
924 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval ||
925 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block ||
926 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_CapturedRegion ||
928 // This closure can capture 'this'; continue looking upwards.
933 // This context can't implicitly capture 'this'; fail out.
934 if (BuildAndDiagnose)
935 Diag(Loc, diag::err_this_capture) << Explicit;
940 if (!BuildAndDiagnose) return false;
941 // Mark that we're implicitly capturing 'this' in all the scopes we skipped.
942 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated
944 for (unsigned idx = MaxFunctionScopesIndex; NumClosures;
945 --idx, --NumClosures) {
946 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]);
947 Expr *ThisExpr = nullptr;
948 QualType ThisTy = getCurrentThisType();
949 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI))
950 // For lambda expressions, build a field and an initializing expression.
951 ThisExpr = captureThis(Context, LSI->Lambda, ThisTy, Loc);
952 else if (CapturedRegionScopeInfo *RSI
953 = dyn_cast<CapturedRegionScopeInfo>(FunctionScopes[idx]))
954 ThisExpr = captureThis(Context, RSI->TheRecordDecl, ThisTy, Loc);
956 bool isNested = NumClosures > 1;
957 CSI->addThisCapture(isNested, Loc, ThisTy, ThisExpr);
962 ExprResult Sema::ActOnCXXThis(SourceLocation Loc) {
963 /// C++ 9.3.2: In the body of a non-static member function, the keyword this
964 /// is a non-lvalue expression whose value is the address of the object for
965 /// which the function is called.
967 QualType ThisTy = getCurrentThisType();
968 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use);
970 CheckCXXThisCapture(Loc);
971 return new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false);
974 bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) {
975 // If we're outside the body of a member function, then we'll have a specified
977 if (CXXThisTypeOverride.isNull())
980 // Determine whether we're looking into a class that's currently being
982 CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl();
983 return Class && Class->isBeingDefined();
987 Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep,
988 SourceLocation LParenLoc,
990 SourceLocation RParenLoc) {
994 TypeSourceInfo *TInfo;
995 QualType Ty = GetTypeFromParser(TypeRep, &TInfo);
997 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation());
999 return BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc);
1002 /// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
1003 /// Can be interpreted either as function-style casting ("int(x)")
1004 /// or class type construction ("ClassType(x,y,z)")
1005 /// or creation of a value-initialized type ("int()").
1007 Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo,
1008 SourceLocation LParenLoc,
1010 SourceLocation RParenLoc) {
1011 QualType Ty = TInfo->getType();
1012 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc();
1014 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(Exprs)) {
1015 return CXXUnresolvedConstructExpr::Create(Context, TInfo, LParenLoc, Exprs,
1019 bool ListInitialization = LParenLoc.isInvalid();
1020 assert((!ListInitialization || (Exprs.size() == 1 && isa<InitListExpr>(Exprs[0])))
1021 && "List initialization must have initializer list as expression.");
1022 SourceRange FullRange = SourceRange(TyBeginLoc,
1023 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc);
1025 // C++ [expr.type.conv]p1:
1026 // If the expression list is a single expression, the type conversion
1027 // expression is equivalent (in definedness, and if defined in meaning) to the
1028 // corresponding cast expression.
1029 if (Exprs.size() == 1 && !ListInitialization) {
1030 Expr *Arg = Exprs[0];
1031 return BuildCXXFunctionalCastExpr(TInfo, LParenLoc, Arg, RParenLoc);
1034 QualType ElemTy = Ty;
1035 if (Ty->isArrayType()) {
1036 if (!ListInitialization)
1037 return ExprError(Diag(TyBeginLoc,
1038 diag::err_value_init_for_array_type) << FullRange);
1039 ElemTy = Context.getBaseElementType(Ty);
1042 if (!Ty->isVoidType() &&
1043 RequireCompleteType(TyBeginLoc, ElemTy,
1044 diag::err_invalid_incomplete_type_use, FullRange))
1047 if (RequireNonAbstractType(TyBeginLoc, Ty,
1048 diag::err_allocation_of_abstract_type))
1051 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo);
1052 InitializationKind Kind =
1053 Exprs.size() ? ListInitialization
1054 ? InitializationKind::CreateDirectList(TyBeginLoc)
1055 : InitializationKind::CreateDirect(TyBeginLoc, LParenLoc, RParenLoc)
1056 : InitializationKind::CreateValue(TyBeginLoc, LParenLoc, RParenLoc);
1057 InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
1058 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Exprs);
1060 if (Result.isInvalid() || !ListInitialization)
1063 Expr *Inner = Result.get();
1064 if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Inner))
1065 Inner = BTE->getSubExpr();
1066 if (!isa<CXXTemporaryObjectExpr>(Inner)) {
1067 // If we created a CXXTemporaryObjectExpr, that node also represents the
1068 // functional cast. Otherwise, create an explicit cast to represent
1069 // the syntactic form of a functional-style cast that was used here.
1071 // FIXME: Creating a CXXFunctionalCastExpr around a CXXConstructExpr
1072 // would give a more consistent AST representation than using a
1073 // CXXTemporaryObjectExpr. It's also weird that the functional cast
1074 // is sometimes handled by initialization and sometimes not.
1075 QualType ResultType = Result.get()->getType();
1076 Result = CXXFunctionalCastExpr::Create(
1077 Context, ResultType, Expr::getValueKindForType(TInfo->getType()), TInfo,
1078 CK_NoOp, Result.get(), /*Path=*/nullptr, LParenLoc, RParenLoc);
1084 /// doesUsualArrayDeleteWantSize - Answers whether the usual
1085 /// operator delete[] for the given type has a size_t parameter.
1086 static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc,
1087 QualType allocType) {
1088 const RecordType *record =
1089 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>();
1090 if (!record) return false;
1092 // Try to find an operator delete[] in class scope.
1094 DeclarationName deleteName =
1095 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete);
1096 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName);
1097 S.LookupQualifiedName(ops, record->getDecl());
1099 // We're just doing this for information.
1100 ops.suppressDiagnostics();
1102 // Very likely: there's no operator delete[].
1103 if (ops.empty()) return false;
1105 // If it's ambiguous, it should be illegal to call operator delete[]
1106 // on this thing, so it doesn't matter if we allocate extra space or not.
1107 if (ops.isAmbiguous()) return false;
1109 LookupResult::Filter filter = ops.makeFilter();
1110 while (filter.hasNext()) {
1111 NamedDecl *del = filter.next()->getUnderlyingDecl();
1113 // C++0x [basic.stc.dynamic.deallocation]p2:
1114 // A template instance is never a usual deallocation function,
1115 // regardless of its signature.
1116 if (isa<FunctionTemplateDecl>(del)) {
1121 // C++0x [basic.stc.dynamic.deallocation]p2:
1122 // If class T does not declare [an operator delete[] with one
1123 // parameter] but does declare a member deallocation function
1124 // named operator delete[] with exactly two parameters, the
1125 // second of which has type std::size_t, then this function
1126 // is a usual deallocation function.
1127 if (!cast<CXXMethodDecl>(del)->isUsualDeallocationFunction()) {
1134 if (!ops.isSingleResult()) return false;
1136 const FunctionDecl *del = cast<FunctionDecl>(ops.getFoundDecl());
1137 return (del->getNumParams() == 2);
1140 /// \brief Parsed a C++ 'new' expression (C++ 5.3.4).
1143 /// @code new (memory) int[size][4] @endcode
1145 /// @code ::new Foo(23, "hello") @endcode
1147 /// \param StartLoc The first location of the expression.
1148 /// \param UseGlobal True if 'new' was prefixed with '::'.
1149 /// \param PlacementLParen Opening paren of the placement arguments.
1150 /// \param PlacementArgs Placement new arguments.
1151 /// \param PlacementRParen Closing paren of the placement arguments.
1152 /// \param TypeIdParens If the type is in parens, the source range.
1153 /// \param D The type to be allocated, as well as array dimensions.
1154 /// \param Initializer The initializing expression or initializer-list, or null
1155 /// if there is none.
1157 Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
1158 SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
1159 SourceLocation PlacementRParen, SourceRange TypeIdParens,
1160 Declarator &D, Expr *Initializer) {
1161 bool TypeContainsAuto = D.getDeclSpec().containsPlaceholderType();
1163 Expr *ArraySize = nullptr;
1164 // If the specified type is an array, unwrap it and save the expression.
1165 if (D.getNumTypeObjects() > 0 &&
1166 D.getTypeObject(0).Kind == DeclaratorChunk::Array) {
1167 DeclaratorChunk &Chunk = D.getTypeObject(0);
1168 if (TypeContainsAuto)
1169 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto)
1170 << D.getSourceRange());
1171 if (Chunk.Arr.hasStatic)
1172 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
1173 << D.getSourceRange());
1174 if (!Chunk.Arr.NumElts)
1175 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
1176 << D.getSourceRange());
1178 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
1179 D.DropFirstTypeObject();
1182 // Every dimension shall be of constant size.
1184 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
1185 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array)
1188 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr;
1189 if (Expr *NumElts = (Expr *)Array.NumElts) {
1190 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
1191 if (getLangOpts().CPlusPlus14) {
1192 // C++1y [expr.new]p6: Every constant-expression in a noptr-new-declarator
1193 // shall be a converted constant expression (5.19) of type std::size_t
1194 // and shall evaluate to a strictly positive value.
1195 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
1196 assert(IntWidth && "Builtin type of size 0?");
1197 llvm::APSInt Value(IntWidth);
1199 = CheckConvertedConstantExpression(NumElts, Context.getSizeType(), Value,
1204 = VerifyIntegerConstantExpression(NumElts, nullptr,
1205 diag::err_new_array_nonconst)
1215 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/nullptr);
1216 QualType AllocType = TInfo->getType();
1217 if (D.isInvalidType())
1220 SourceRange DirectInitRange;
1221 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer))
1222 DirectInitRange = List->getSourceRange();
1224 return BuildCXXNew(SourceRange(StartLoc, D.getLocEnd()), UseGlobal,
1237 static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style,
1241 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init))
1242 return PLE->getNumExprs() == 0;
1243 if (isa<ImplicitValueInitExpr>(Init))
1245 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init))
1246 return !CCE->isListInitialization() &&
1247 CCE->getConstructor()->isDefaultConstructor();
1248 else if (Style == CXXNewExpr::ListInit) {
1249 assert(isa<InitListExpr>(Init) &&
1250 "Shouldn't create list CXXConstructExprs for arrays.");
1257 Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
1258 SourceLocation PlacementLParen,
1259 MultiExprArg PlacementArgs,
1260 SourceLocation PlacementRParen,
1261 SourceRange TypeIdParens,
1263 TypeSourceInfo *AllocTypeInfo,
1265 SourceRange DirectInitRange,
1267 bool TypeMayContainAuto) {
1268 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange();
1269 SourceLocation StartLoc = Range.getBegin();
1271 CXXNewExpr::InitializationStyle initStyle;
1272 if (DirectInitRange.isValid()) {
1273 assert(Initializer && "Have parens but no initializer.");
1274 initStyle = CXXNewExpr::CallInit;
1275 } else if (Initializer && isa<InitListExpr>(Initializer))
1276 initStyle = CXXNewExpr::ListInit;
1278 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) ||
1279 isa<CXXConstructExpr>(Initializer)) &&
1280 "Initializer expression that cannot have been implicitly created.");
1281 initStyle = CXXNewExpr::NoInit;
1284 Expr **Inits = &Initializer;
1285 unsigned NumInits = Initializer ? 1 : 0;
1286 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) {
1287 assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init");
1288 Inits = List->getExprs();
1289 NumInits = List->getNumExprs();
1292 // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
1293 if (TypeMayContainAuto && AllocType->isUndeducedType()) {
1294 if (initStyle == CXXNewExpr::NoInit || NumInits == 0)
1295 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg)
1296 << AllocType << TypeRange);
1297 if (initStyle == CXXNewExpr::ListInit ||
1298 (NumInits == 1 && isa<InitListExpr>(Inits[0])))
1299 return ExprError(Diag(Inits[0]->getLocStart(),
1300 diag::err_auto_new_list_init)
1301 << AllocType << TypeRange);
1303 Expr *FirstBad = Inits[1];
1304 return ExprError(Diag(FirstBad->getLocStart(),
1305 diag::err_auto_new_ctor_multiple_expressions)
1306 << AllocType << TypeRange);
1308 Expr *Deduce = Inits[0];
1309 QualType DeducedType;
1310 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed)
1311 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure)
1312 << AllocType << Deduce->getType()
1313 << TypeRange << Deduce->getSourceRange());
1314 if (DeducedType.isNull())
1316 AllocType = DeducedType;
1319 // Per C++0x [expr.new]p5, the type being constructed may be a
1320 // typedef of an array type.
1322 if (const ConstantArrayType *Array
1323 = Context.getAsConstantArrayType(AllocType)) {
1324 ArraySize = IntegerLiteral::Create(Context, Array->getSize(),
1325 Context.getSizeType(),
1326 TypeRange.getEnd());
1327 AllocType = Array->getElementType();
1331 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange))
1334 if (initStyle == CXXNewExpr::ListInit &&
1335 isStdInitializerList(AllocType, nullptr)) {
1336 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(),
1337 diag::warn_dangling_std_initializer_list)
1338 << /*at end of FE*/0 << Inits[0]->getSourceRange();
1341 // In ARC, infer 'retaining' for the allocated
1342 if (getLangOpts().ObjCAutoRefCount &&
1343 AllocType.getObjCLifetime() == Qualifiers::OCL_None &&
1344 AllocType->isObjCLifetimeType()) {
1345 AllocType = Context.getLifetimeQualifiedType(AllocType,
1346 AllocType->getObjCARCImplicitLifetime());
1349 QualType ResultType = Context.getPointerType(AllocType);
1351 if (ArraySize && ArraySize->getType()->isNonOverloadPlaceholderType()) {
1352 ExprResult result = CheckPlaceholderExpr(ArraySize);
1353 if (result.isInvalid()) return ExprError();
1354 ArraySize = result.get();
1356 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have
1357 // integral or enumeration type with a non-negative value."
1358 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped
1359 // enumeration type, or a class type for which a single non-explicit
1360 // conversion function to integral or unscoped enumeration type exists.
1361 // C++1y [expr.new]p6: The expression [...] is implicitly converted to
1363 if (ArraySize && !ArraySize->isTypeDependent()) {
1364 ExprResult ConvertedSize;
1365 if (getLangOpts().CPlusPlus14) {
1366 assert(Context.getTargetInfo().getIntWidth() && "Builtin type of size 0?");
1368 ConvertedSize = PerformImplicitConversion(ArraySize, Context.getSizeType(),
1371 if (!ConvertedSize.isInvalid() &&
1372 ArraySize->getType()->getAs<RecordType>())
1373 // Diagnose the compatibility of this conversion.
1374 Diag(StartLoc, diag::warn_cxx98_compat_array_size_conversion)
1375 << ArraySize->getType() << 0 << "'size_t'";
1377 class SizeConvertDiagnoser : public ICEConvertDiagnoser {
1382 SizeConvertDiagnoser(Expr *ArraySize)
1383 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false, false, false),
1384 ArraySize(ArraySize) {}
1386 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
1387 QualType T) override {
1388 return S.Diag(Loc, diag::err_array_size_not_integral)
1389 << S.getLangOpts().CPlusPlus11 << T;
1392 SemaDiagnosticBuilder diagnoseIncomplete(
1393 Sema &S, SourceLocation Loc, QualType T) override {
1394 return S.Diag(Loc, diag::err_array_size_incomplete_type)
1395 << T << ArraySize->getSourceRange();
1398 SemaDiagnosticBuilder diagnoseExplicitConv(
1399 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
1400 return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy;
1403 SemaDiagnosticBuilder noteExplicitConv(
1404 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1405 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1406 << ConvTy->isEnumeralType() << ConvTy;
1409 SemaDiagnosticBuilder diagnoseAmbiguous(
1410 Sema &S, SourceLocation Loc, QualType T) override {
1411 return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T;
1414 SemaDiagnosticBuilder noteAmbiguous(
1415 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1416 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1417 << ConvTy->isEnumeralType() << ConvTy;
1420 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
1422 QualType ConvTy) override {
1424 S.getLangOpts().CPlusPlus11
1425 ? diag::warn_cxx98_compat_array_size_conversion
1426 : diag::ext_array_size_conversion)
1427 << T << ConvTy->isEnumeralType() << ConvTy;
1429 } SizeDiagnoser(ArraySize);
1431 ConvertedSize = PerformContextualImplicitConversion(StartLoc, ArraySize,
1434 if (ConvertedSize.isInvalid())
1437 ArraySize = ConvertedSize.get();
1438 QualType SizeType = ArraySize->getType();
1440 if (!SizeType->isIntegralOrUnscopedEnumerationType())
1443 // C++98 [expr.new]p7:
1444 // The expression in a direct-new-declarator shall have integral type
1445 // with a non-negative value.
1447 // Let's see if this is a constant < 0. If so, we reject it out of
1448 // hand. Otherwise, if it's not a constant, we must have an unparenthesized
1451 // Note: such a construct has well-defined semantics in C++11: it throws
1452 // std::bad_array_new_length.
1453 if (!ArraySize->isValueDependent()) {
1455 // We've already performed any required implicit conversion to integer or
1456 // unscoped enumeration type.
1457 if (ArraySize->isIntegerConstantExpr(Value, Context)) {
1458 if (Value < llvm::APSInt(
1459 llvm::APInt::getNullValue(Value.getBitWidth()),
1460 Value.isUnsigned())) {
1461 if (getLangOpts().CPlusPlus11)
1462 Diag(ArraySize->getLocStart(),
1463 diag::warn_typecheck_negative_array_new_size)
1464 << ArraySize->getSourceRange();
1466 return ExprError(Diag(ArraySize->getLocStart(),
1467 diag::err_typecheck_negative_array_size)
1468 << ArraySize->getSourceRange());
1469 } else if (!AllocType->isDependentType()) {
1470 unsigned ActiveSizeBits =
1471 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value);
1472 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
1473 if (getLangOpts().CPlusPlus11)
1474 Diag(ArraySize->getLocStart(),
1475 diag::warn_array_new_too_large)
1476 << Value.toString(10)
1477 << ArraySize->getSourceRange();
1479 return ExprError(Diag(ArraySize->getLocStart(),
1480 diag::err_array_too_large)
1481 << Value.toString(10)
1482 << ArraySize->getSourceRange());
1485 } else if (TypeIdParens.isValid()) {
1486 // Can't have dynamic array size when the type-id is in parentheses.
1487 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst)
1488 << ArraySize->getSourceRange()
1489 << FixItHint::CreateRemoval(TypeIdParens.getBegin())
1490 << FixItHint::CreateRemoval(TypeIdParens.getEnd());
1492 TypeIdParens = SourceRange();
1496 // Note that we do *not* convert the argument in any way. It can
1497 // be signed, larger than size_t, whatever.
1500 FunctionDecl *OperatorNew = nullptr;
1501 FunctionDecl *OperatorDelete = nullptr;
1503 if (!AllocType->isDependentType() &&
1504 !Expr::hasAnyTypeDependentArguments(PlacementArgs) &&
1505 FindAllocationFunctions(StartLoc,
1506 SourceRange(PlacementLParen, PlacementRParen),
1507 UseGlobal, AllocType, ArraySize, PlacementArgs,
1508 OperatorNew, OperatorDelete))
1511 // If this is an array allocation, compute whether the usual array
1512 // deallocation function for the type has a size_t parameter.
1513 bool UsualArrayDeleteWantsSize = false;
1514 if (ArraySize && !AllocType->isDependentType())
1515 UsualArrayDeleteWantsSize
1516 = doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType);
1518 SmallVector<Expr *, 8> AllPlaceArgs;
1520 const FunctionProtoType *Proto =
1521 OperatorNew->getType()->getAs<FunctionProtoType>();
1522 VariadicCallType CallType = Proto->isVariadic() ? VariadicFunction
1523 : VariadicDoesNotApply;
1525 // We've already converted the placement args, just fill in any default
1526 // arguments. Skip the first parameter because we don't have a corresponding
1528 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, Proto, 1,
1529 PlacementArgs, AllPlaceArgs, CallType))
1532 if (!AllPlaceArgs.empty())
1533 PlacementArgs = AllPlaceArgs;
1535 // FIXME: This is wrong: PlacementArgs misses out the first (size) argument.
1536 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, PlacementArgs);
1538 // FIXME: Missing call to CheckFunctionCall or equivalent
1541 // Warn if the type is over-aligned and is being allocated by global operator
1543 if (PlacementArgs.empty() && OperatorNew &&
1544 (OperatorNew->isImplicit() ||
1545 getSourceManager().isInSystemHeader(OperatorNew->getLocStart()))) {
1546 if (unsigned Align = Context.getPreferredTypeAlign(AllocType.getTypePtr())){
1547 unsigned SuitableAlign = Context.getTargetInfo().getSuitableAlign();
1548 if (Align > SuitableAlign)
1549 Diag(StartLoc, diag::warn_overaligned_type)
1551 << unsigned(Align / Context.getCharWidth())
1552 << unsigned(SuitableAlign / Context.getCharWidth());
1556 QualType InitType = AllocType;
1557 // Array 'new' can't have any initializers except empty parentheses.
1558 // Initializer lists are also allowed, in C++11. Rely on the parser for the
1559 // dialect distinction.
1560 if (ResultType->isArrayType() || ArraySize) {
1561 if (!isLegalArrayNewInitializer(initStyle, Initializer)) {
1562 SourceRange InitRange(Inits[0]->getLocStart(),
1563 Inits[NumInits - 1]->getLocEnd());
1564 Diag(StartLoc, diag::err_new_array_init_args) << InitRange;
1567 if (InitListExpr *ILE = dyn_cast_or_null<InitListExpr>(Initializer)) {
1568 // We do the initialization typechecking against the array type
1569 // corresponding to the number of initializers + 1 (to also check
1570 // default-initialization).
1571 unsigned NumElements = ILE->getNumInits() + 1;
1572 InitType = Context.getConstantArrayType(AllocType,
1573 llvm::APInt(Context.getTypeSize(Context.getSizeType()), NumElements),
1574 ArrayType::Normal, 0);
1578 // If we can perform the initialization, and we've not already done so,
1580 if (!AllocType->isDependentType() &&
1581 !Expr::hasAnyTypeDependentArguments(
1582 llvm::makeArrayRef(Inits, NumInits))) {
1583 // C++11 [expr.new]p15:
1584 // A new-expression that creates an object of type T initializes that
1585 // object as follows:
1586 InitializationKind Kind
1587 // - If the new-initializer is omitted, the object is default-
1588 // initialized (8.5); if no initialization is performed,
1589 // the object has indeterminate value
1590 = initStyle == CXXNewExpr::NoInit
1591 ? InitializationKind::CreateDefault(TypeRange.getBegin())
1592 // - Otherwise, the new-initializer is interpreted according to the
1593 // initialization rules of 8.5 for direct-initialization.
1594 : initStyle == CXXNewExpr::ListInit
1595 ? InitializationKind::CreateDirectList(TypeRange.getBegin())
1596 : InitializationKind::CreateDirect(TypeRange.getBegin(),
1597 DirectInitRange.getBegin(),
1598 DirectInitRange.getEnd());
1600 InitializedEntity Entity
1601 = InitializedEntity::InitializeNew(StartLoc, InitType);
1602 InitializationSequence InitSeq(*this, Entity, Kind, MultiExprArg(Inits, NumInits));
1603 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind,
1604 MultiExprArg(Inits, NumInits));
1605 if (FullInit.isInvalid())
1608 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because
1609 // we don't want the initialized object to be destructed.
1610 if (CXXBindTemporaryExpr *Binder =
1611 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get()))
1612 FullInit = Binder->getSubExpr();
1614 Initializer = FullInit.get();
1617 // Mark the new and delete operators as referenced.
1619 if (DiagnoseUseOfDecl(OperatorNew, StartLoc))
1621 MarkFunctionReferenced(StartLoc, OperatorNew);
1623 if (OperatorDelete) {
1624 if (DiagnoseUseOfDecl(OperatorDelete, StartLoc))
1626 MarkFunctionReferenced(StartLoc, OperatorDelete);
1629 // C++0x [expr.new]p17:
1630 // If the new expression creates an array of objects of class type,
1631 // access and ambiguity control are done for the destructor.
1632 QualType BaseAllocType = Context.getBaseElementType(AllocType);
1633 if (ArraySize && !BaseAllocType->isDependentType()) {
1634 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) {
1635 if (CXXDestructorDecl *dtor = LookupDestructor(
1636 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) {
1637 MarkFunctionReferenced(StartLoc, dtor);
1638 CheckDestructorAccess(StartLoc, dtor,
1639 PDiag(diag::err_access_dtor)
1641 if (DiagnoseUseOfDecl(dtor, StartLoc))
1647 return new (Context)
1648 CXXNewExpr(Context, UseGlobal, OperatorNew, OperatorDelete,
1649 UsualArrayDeleteWantsSize, PlacementArgs, TypeIdParens,
1650 ArraySize, initStyle, Initializer, ResultType, AllocTypeInfo,
1651 Range, DirectInitRange);
1654 /// \brief Checks that a type is suitable as the allocated type
1655 /// in a new-expression.
1656 bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc,
1658 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
1659 // abstract class type or array thereof.
1660 if (AllocType->isFunctionType())
1661 return Diag(Loc, diag::err_bad_new_type)
1662 << AllocType << 0 << R;
1663 else if (AllocType->isReferenceType())
1664 return Diag(Loc, diag::err_bad_new_type)
1665 << AllocType << 1 << R;
1666 else if (!AllocType->isDependentType() &&
1667 RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R))
1669 else if (RequireNonAbstractType(Loc, AllocType,
1670 diag::err_allocation_of_abstract_type))
1672 else if (AllocType->isVariablyModifiedType())
1673 return Diag(Loc, diag::err_variably_modified_new_type)
1675 else if (unsigned AddressSpace = AllocType.getAddressSpace())
1676 return Diag(Loc, diag::err_address_space_qualified_new)
1677 << AllocType.getUnqualifiedType() << AddressSpace;
1678 else if (getLangOpts().ObjCAutoRefCount) {
1679 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) {
1680 QualType BaseAllocType = Context.getBaseElementType(AT);
1681 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None &&
1682 BaseAllocType->isObjCLifetimeType())
1683 return Diag(Loc, diag::err_arc_new_array_without_ownership)
1691 /// \brief Determine whether the given function is a non-placement
1692 /// deallocation function.
1693 static bool isNonPlacementDeallocationFunction(Sema &S, FunctionDecl *FD) {
1694 if (FD->isInvalidDecl())
1697 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD))
1698 return Method->isUsualDeallocationFunction();
1700 if (FD->getOverloadedOperator() != OO_Delete &&
1701 FD->getOverloadedOperator() != OO_Array_Delete)
1704 if (FD->getNumParams() == 1)
1707 return S.getLangOpts().SizedDeallocation && FD->getNumParams() == 2 &&
1708 S.Context.hasSameUnqualifiedType(FD->getParamDecl(1)->getType(),
1709 S.Context.getSizeType());
1712 /// FindAllocationFunctions - Finds the overloads of operator new and delete
1713 /// that are appropriate for the allocation.
1714 bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
1715 bool UseGlobal, QualType AllocType,
1716 bool IsArray, MultiExprArg PlaceArgs,
1717 FunctionDecl *&OperatorNew,
1718 FunctionDecl *&OperatorDelete) {
1719 // --- Choosing an allocation function ---
1720 // C++ 5.3.4p8 - 14 & 18
1721 // 1) If UseGlobal is true, only look in the global scope. Else, also look
1722 // in the scope of the allocated class.
1723 // 2) If an array size is given, look for operator new[], else look for
1725 // 3) The first argument is always size_t. Append the arguments from the
1728 SmallVector<Expr*, 8> AllocArgs(1 + PlaceArgs.size());
1729 // We don't care about the actual value of this argument.
1730 // FIXME: Should the Sema create the expression and embed it in the syntax
1731 // tree? Or should the consumer just recalculate the value?
1732 IntegerLiteral Size(Context, llvm::APInt::getNullValue(
1733 Context.getTargetInfo().getPointerWidth(0)),
1734 Context.getSizeType(),
1736 AllocArgs[0] = &Size;
1737 std::copy(PlaceArgs.begin(), PlaceArgs.end(), AllocArgs.begin() + 1);
1739 // C++ [expr.new]p8:
1740 // If the allocated type is a non-array type, the allocation
1741 // function's name is operator new and the deallocation function's
1742 // name is operator delete. If the allocated type is an array
1743 // type, the allocation function's name is operator new[] and the
1744 // deallocation function's name is operator delete[].
1745 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName(
1746 IsArray ? OO_Array_New : OO_New);
1747 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
1748 IsArray ? OO_Array_Delete : OO_Delete);
1750 QualType AllocElemType = Context.getBaseElementType(AllocType);
1752 if (AllocElemType->isRecordType() && !UseGlobal) {
1753 CXXRecordDecl *Record
1754 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl());
1755 if (FindAllocationOverload(StartLoc, Range, NewName, AllocArgs, Record,
1756 /*AllowMissing=*/true, OperatorNew))
1761 // Didn't find a member overload. Look for a global one.
1762 DeclareGlobalNewDelete();
1763 DeclContext *TUDecl = Context.getTranslationUnitDecl();
1764 bool FallbackEnabled = IsArray && Context.getLangOpts().MSVCCompat;
1765 if (FindAllocationOverload(StartLoc, Range, NewName, AllocArgs, TUDecl,
1766 /*AllowMissing=*/FallbackEnabled, OperatorNew,
1767 /*Diagnose=*/!FallbackEnabled)) {
1768 if (!FallbackEnabled)
1771 // MSVC will fall back on trying to find a matching global operator new
1772 // if operator new[] cannot be found. Also, MSVC will leak by not
1773 // generating a call to operator delete or operator delete[], but we
1774 // will not replicate that bug.
1775 NewName = Context.DeclarationNames.getCXXOperatorName(OO_New);
1776 DeleteName = Context.DeclarationNames.getCXXOperatorName(OO_Delete);
1777 if (FindAllocationOverload(StartLoc, Range, NewName, AllocArgs, TUDecl,
1778 /*AllowMissing=*/false, OperatorNew))
1783 // We don't need an operator delete if we're running under
1785 if (!getLangOpts().Exceptions) {
1786 OperatorDelete = nullptr;
1790 // C++ [expr.new]p19:
1792 // If the new-expression begins with a unary :: operator, the
1793 // deallocation function's name is looked up in the global
1794 // scope. Otherwise, if the allocated type is a class type T or an
1795 // array thereof, the deallocation function's name is looked up in
1796 // the scope of T. If this lookup fails to find the name, or if
1797 // the allocated type is not a class type or array thereof, the
1798 // deallocation function's name is looked up in the global scope.
1799 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName);
1800 if (AllocElemType->isRecordType() && !UseGlobal) {
1802 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl());
1803 LookupQualifiedName(FoundDelete, RD);
1805 if (FoundDelete.isAmbiguous())
1806 return true; // FIXME: clean up expressions?
1808 if (FoundDelete.empty()) {
1809 DeclareGlobalNewDelete();
1810 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
1813 FoundDelete.suppressDiagnostics();
1815 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches;
1817 // Whether we're looking for a placement operator delete is dictated
1818 // by whether we selected a placement operator new, not by whether
1819 // we had explicit placement arguments. This matters for things like
1820 // struct A { void *operator new(size_t, int = 0); ... };
1822 bool isPlacementNew = (!PlaceArgs.empty() || OperatorNew->param_size() != 1);
1824 if (isPlacementNew) {
1825 // C++ [expr.new]p20:
1826 // A declaration of a placement deallocation function matches the
1827 // declaration of a placement allocation function if it has the
1828 // same number of parameters and, after parameter transformations
1829 // (8.3.5), all parameter types except the first are
1832 // To perform this comparison, we compute the function type that
1833 // the deallocation function should have, and use that type both
1834 // for template argument deduction and for comparison purposes.
1836 // FIXME: this comparison should ignore CC and the like.
1837 QualType ExpectedFunctionType;
1839 const FunctionProtoType *Proto
1840 = OperatorNew->getType()->getAs<FunctionProtoType>();
1842 SmallVector<QualType, 4> ArgTypes;
1843 ArgTypes.push_back(Context.VoidPtrTy);
1844 for (unsigned I = 1, N = Proto->getNumParams(); I < N; ++I)
1845 ArgTypes.push_back(Proto->getParamType(I));
1847 FunctionProtoType::ExtProtoInfo EPI;
1848 EPI.Variadic = Proto->isVariadic();
1850 ExpectedFunctionType
1851 = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI);
1854 for (LookupResult::iterator D = FoundDelete.begin(),
1855 DEnd = FoundDelete.end();
1857 FunctionDecl *Fn = nullptr;
1858 if (FunctionTemplateDecl *FnTmpl
1859 = dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) {
1860 // Perform template argument deduction to try to match the
1861 // expected function type.
1862 TemplateDeductionInfo Info(StartLoc);
1863 if (DeduceTemplateArguments(FnTmpl, nullptr, ExpectedFunctionType, Fn,
1867 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl());
1869 if (Context.hasSameType(Fn->getType(), ExpectedFunctionType))
1870 Matches.push_back(std::make_pair(D.getPair(), Fn));
1873 // C++ [expr.new]p20:
1874 // [...] Any non-placement deallocation function matches a
1875 // non-placement allocation function. [...]
1876 for (LookupResult::iterator D = FoundDelete.begin(),
1877 DEnd = FoundDelete.end();
1879 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>((*D)->getUnderlyingDecl()))
1880 if (isNonPlacementDeallocationFunction(*this, Fn))
1881 Matches.push_back(std::make_pair(D.getPair(), Fn));
1884 // C++1y [expr.new]p22:
1885 // For a non-placement allocation function, the normal deallocation
1886 // function lookup is used
1887 // C++1y [expr.delete]p?:
1888 // If [...] deallocation function lookup finds both a usual deallocation
1889 // function with only a pointer parameter and a usual deallocation
1890 // function with both a pointer parameter and a size parameter, then the
1891 // selected deallocation function shall be the one with two parameters.
1892 // Otherwise, the selected deallocation function shall be the function
1893 // with one parameter.
1894 if (getLangOpts().SizedDeallocation && Matches.size() == 2) {
1895 if (Matches[0].second->getNumParams() == 1)
1896 Matches.erase(Matches.begin());
1898 Matches.erase(Matches.begin() + 1);
1899 assert(Matches[0].second->getNumParams() == 2 &&
1900 "found an unexpected usual deallocation function");
1904 // C++ [expr.new]p20:
1905 // [...] If the lookup finds a single matching deallocation
1906 // function, that function will be called; otherwise, no
1907 // deallocation function will be called.
1908 if (Matches.size() == 1) {
1909 OperatorDelete = Matches[0].second;
1911 // C++0x [expr.new]p20:
1912 // If the lookup finds the two-parameter form of a usual
1913 // deallocation function (3.7.4.2) and that function, considered
1914 // as a placement deallocation function, would have been
1915 // selected as a match for the allocation function, the program
1917 if (!PlaceArgs.empty() && getLangOpts().CPlusPlus11 &&
1918 isNonPlacementDeallocationFunction(*this, OperatorDelete)) {
1919 Diag(StartLoc, diag::err_placement_new_non_placement_delete)
1920 << SourceRange(PlaceArgs.front()->getLocStart(),
1921 PlaceArgs.back()->getLocEnd());
1922 if (!OperatorDelete->isImplicit())
1923 Diag(OperatorDelete->getLocation(), diag::note_previous_decl)
1926 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(),
1934 /// \brief Find an fitting overload for the allocation function
1935 /// in the specified scope.
1937 /// \param StartLoc The location of the 'new' token.
1938 /// \param Range The range of the placement arguments.
1939 /// \param Name The name of the function ('operator new' or 'operator new[]').
1940 /// \param Args The placement arguments specified.
1941 /// \param Ctx The scope in which we should search; either a class scope or the
1942 /// translation unit.
1943 /// \param AllowMissing If \c true, report an error if we can't find any
1944 /// allocation functions. Otherwise, succeed but don't fill in \p
1946 /// \param Operator Filled in with the found allocation function. Unchanged if
1947 /// no allocation function was found.
1948 /// \param Diagnose If \c true, issue errors if the allocation function is not
1950 bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range,
1951 DeclarationName Name, MultiExprArg Args,
1953 bool AllowMissing, FunctionDecl *&Operator,
1955 LookupResult R(*this, Name, StartLoc, LookupOrdinaryName);
1956 LookupQualifiedName(R, Ctx);
1958 if (AllowMissing || !Diagnose)
1960 return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call)
1964 if (R.isAmbiguous())
1967 R.suppressDiagnostics();
1969 OverloadCandidateSet Candidates(StartLoc, OverloadCandidateSet::CSK_Normal);
1970 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
1971 Alloc != AllocEnd; ++Alloc) {
1972 // Even member operator new/delete are implicitly treated as
1973 // static, so don't use AddMemberCandidate.
1974 NamedDecl *D = (*Alloc)->getUnderlyingDecl();
1976 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
1977 AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(),
1978 /*ExplicitTemplateArgs=*/nullptr,
1980 /*SuppressUserConversions=*/false);
1984 FunctionDecl *Fn = cast<FunctionDecl>(D);
1985 AddOverloadCandidate(Fn, Alloc.getPair(), Args, Candidates,
1986 /*SuppressUserConversions=*/false);
1989 // Do the resolution.
1990 OverloadCandidateSet::iterator Best;
1991 switch (Candidates.BestViableFunction(*this, StartLoc, Best)) {
1994 FunctionDecl *FnDecl = Best->Function;
1995 if (CheckAllocationAccess(StartLoc, Range, R.getNamingClass(),
1996 Best->FoundDecl, Diagnose) == AR_inaccessible)
2003 case OR_No_Viable_Function:
2005 Diag(StartLoc, diag::err_ovl_no_viable_function_in_call)
2007 Candidates.NoteCandidates(*this, OCD_AllCandidates, Args);
2013 Diag(StartLoc, diag::err_ovl_ambiguous_call)
2015 Candidates.NoteCandidates(*this, OCD_ViableCandidates, Args);
2021 Diag(StartLoc, diag::err_ovl_deleted_call)
2022 << Best->Function->isDeleted()
2024 << getDeletedOrUnavailableSuffix(Best->Function)
2026 Candidates.NoteCandidates(*this, OCD_AllCandidates, Args);
2031 llvm_unreachable("Unreachable, bad result from BestViableFunction");
2035 /// DeclareGlobalNewDelete - Declare the global forms of operator new and
2036 /// delete. These are:
2039 /// void* operator new(std::size_t) throw(std::bad_alloc);
2040 /// void* operator new[](std::size_t) throw(std::bad_alloc);
2041 /// void operator delete(void *) throw();
2042 /// void operator delete[](void *) throw();
2044 /// void* operator new(std::size_t);
2045 /// void* operator new[](std::size_t);
2046 /// void operator delete(void *) noexcept;
2047 /// void operator delete[](void *) noexcept;
2049 /// void* operator new(std::size_t);
2050 /// void* operator new[](std::size_t);
2051 /// void operator delete(void *) noexcept;
2052 /// void operator delete[](void *) noexcept;
2053 /// void operator delete(void *, std::size_t) noexcept;
2054 /// void operator delete[](void *, std::size_t) noexcept;
2056 /// Note that the placement and nothrow forms of new are *not* implicitly
2057 /// declared. Their use requires including \<new\>.
2058 void Sema::DeclareGlobalNewDelete() {
2059 if (GlobalNewDeleteDeclared)
2062 // C++ [basic.std.dynamic]p2:
2063 // [...] The following allocation and deallocation functions (18.4) are
2064 // implicitly declared in global scope in each translation unit of a
2068 // void* operator new(std::size_t) throw(std::bad_alloc);
2069 // void* operator new[](std::size_t) throw(std::bad_alloc);
2070 // void operator delete(void*) throw();
2071 // void operator delete[](void*) throw();
2073 // void* operator new(std::size_t);
2074 // void* operator new[](std::size_t);
2075 // void operator delete(void*) noexcept;
2076 // void operator delete[](void*) noexcept;
2078 // void* operator new(std::size_t);
2079 // void* operator new[](std::size_t);
2080 // void operator delete(void*) noexcept;
2081 // void operator delete[](void*) noexcept;
2082 // void operator delete(void*, std::size_t) noexcept;
2083 // void operator delete[](void*, std::size_t) noexcept;
2085 // These implicit declarations introduce only the function names operator
2086 // new, operator new[], operator delete, operator delete[].
2088 // Here, we need to refer to std::bad_alloc, so we will implicitly declare
2089 // "std" or "bad_alloc" as necessary to form the exception specification.
2090 // However, we do not make these implicit declarations visible to name
2092 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) {
2093 // The "std::bad_alloc" class has not yet been declared, so build it
2095 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class,
2096 getOrCreateStdNamespace(),
2097 SourceLocation(), SourceLocation(),
2098 &PP.getIdentifierTable().get("bad_alloc"),
2100 getStdBadAlloc()->setImplicit(true);
2103 GlobalNewDeleteDeclared = true;
2105 QualType VoidPtr = Context.getPointerType(Context.VoidTy);
2106 QualType SizeT = Context.getSizeType();
2107 bool AssumeSaneOperatorNew = getLangOpts().AssumeSaneOperatorNew;
2109 DeclareGlobalAllocationFunction(
2110 Context.DeclarationNames.getCXXOperatorName(OO_New),
2111 VoidPtr, SizeT, QualType(), AssumeSaneOperatorNew);
2112 DeclareGlobalAllocationFunction(
2113 Context.DeclarationNames.getCXXOperatorName(OO_Array_New),
2114 VoidPtr, SizeT, QualType(), AssumeSaneOperatorNew);
2115 DeclareGlobalAllocationFunction(
2116 Context.DeclarationNames.getCXXOperatorName(OO_Delete),
2117 Context.VoidTy, VoidPtr);
2118 DeclareGlobalAllocationFunction(
2119 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete),
2120 Context.VoidTy, VoidPtr);
2121 if (getLangOpts().SizedDeallocation) {
2122 DeclareGlobalAllocationFunction(
2123 Context.DeclarationNames.getCXXOperatorName(OO_Delete),
2124 Context.VoidTy, VoidPtr, Context.getSizeType());
2125 DeclareGlobalAllocationFunction(
2126 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete),
2127 Context.VoidTy, VoidPtr, Context.getSizeType());
2131 /// DeclareGlobalAllocationFunction - Declares a single implicit global
2132 /// allocation function if it doesn't already exist.
2133 void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
2135 QualType Param1, QualType Param2,
2136 bool AddRestrictAttr) {
2137 DeclContext *GlobalCtx = Context.getTranslationUnitDecl();
2138 unsigned NumParams = Param2.isNull() ? 1 : 2;
2140 // Check if this function is already declared.
2141 DeclContext::lookup_result R = GlobalCtx->lookup(Name);
2142 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end();
2143 Alloc != AllocEnd; ++Alloc) {
2144 // Only look at non-template functions, as it is the predefined,
2145 // non-templated allocation function we are trying to declare here.
2146 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
2147 if (Func->getNumParams() == NumParams) {
2148 QualType InitialParam1Type =
2149 Context.getCanonicalType(Func->getParamDecl(0)
2150 ->getType().getUnqualifiedType());
2151 QualType InitialParam2Type =
2153 ? Context.getCanonicalType(Func->getParamDecl(1)
2154 ->getType().getUnqualifiedType())
2156 // FIXME: Do we need to check for default arguments here?
2157 if (InitialParam1Type == Param1 &&
2158 (NumParams == 1 || InitialParam2Type == Param2)) {
2159 if (AddRestrictAttr && !Func->hasAttr<RestrictAttr>())
2160 Func->addAttr(RestrictAttr::CreateImplicit(
2161 Context, RestrictAttr::GNU_malloc));
2162 // Make the function visible to name lookup, even if we found it in
2163 // an unimported module. It either is an implicitly-declared global
2164 // allocation function, or is suppressing that function.
2165 Func->setHidden(false);
2172 FunctionProtoType::ExtProtoInfo EPI;
2174 QualType BadAllocType;
2175 bool HasBadAllocExceptionSpec
2176 = (Name.getCXXOverloadedOperator() == OO_New ||
2177 Name.getCXXOverloadedOperator() == OO_Array_New);
2178 if (HasBadAllocExceptionSpec) {
2179 if (!getLangOpts().CPlusPlus11) {
2180 BadAllocType = Context.getTypeDeclType(getStdBadAlloc());
2181 assert(StdBadAlloc && "Must have std::bad_alloc declared");
2182 EPI.ExceptionSpec.Type = EST_Dynamic;
2183 EPI.ExceptionSpec.Exceptions = llvm::makeArrayRef(BadAllocType);
2187 getLangOpts().CPlusPlus11 ? EST_BasicNoexcept : EST_DynamicNone;
2190 QualType Params[] = { Param1, Param2 };
2192 QualType FnType = Context.getFunctionType(
2193 Return, llvm::makeArrayRef(Params, NumParams), EPI);
2194 FunctionDecl *Alloc =
2195 FunctionDecl::Create(Context, GlobalCtx, SourceLocation(),
2196 SourceLocation(), Name,
2197 FnType, /*TInfo=*/nullptr, SC_None, false, true);
2198 Alloc->setImplicit();
2200 // Implicit sized deallocation functions always have default visibility.
2201 Alloc->addAttr(VisibilityAttr::CreateImplicit(Context,
2202 VisibilityAttr::Default));
2204 if (AddRestrictAttr)
2206 RestrictAttr::CreateImplicit(Context, RestrictAttr::GNU_malloc));
2208 ParmVarDecl *ParamDecls[2];
2209 for (unsigned I = 0; I != NumParams; ++I) {
2210 ParamDecls[I] = ParmVarDecl::Create(Context, Alloc, SourceLocation(),
2211 SourceLocation(), nullptr,
2212 Params[I], /*TInfo=*/nullptr,
2214 ParamDecls[I]->setImplicit();
2216 Alloc->setParams(llvm::makeArrayRef(ParamDecls, NumParams));
2218 Context.getTranslationUnitDecl()->addDecl(Alloc);
2219 IdResolver.tryAddTopLevelDecl(Alloc, Name);
2222 FunctionDecl *Sema::FindUsualDeallocationFunction(SourceLocation StartLoc,
2223 bool CanProvideSize,
2224 DeclarationName Name) {
2225 DeclareGlobalNewDelete();
2227 LookupResult FoundDelete(*this, Name, StartLoc, LookupOrdinaryName);
2228 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2230 // C++ [expr.new]p20:
2231 // [...] Any non-placement deallocation function matches a
2232 // non-placement allocation function. [...]
2233 llvm::SmallVector<FunctionDecl*, 2> Matches;
2234 for (LookupResult::iterator D = FoundDelete.begin(),
2235 DEnd = FoundDelete.end();
2237 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>(*D))
2238 if (isNonPlacementDeallocationFunction(*this, Fn))
2239 Matches.push_back(Fn);
2242 // C++1y [expr.delete]p?:
2243 // If the type is complete and deallocation function lookup finds both a
2244 // usual deallocation function with only a pointer parameter and a usual
2245 // deallocation function with both a pointer parameter and a size
2246 // parameter, then the selected deallocation function shall be the one
2247 // with two parameters. Otherwise, the selected deallocation function
2248 // shall be the function with one parameter.
2249 if (getLangOpts().SizedDeallocation && Matches.size() == 2) {
2250 unsigned NumArgs = CanProvideSize ? 2 : 1;
2251 if (Matches[0]->getNumParams() != NumArgs)
2252 Matches.erase(Matches.begin());
2254 Matches.erase(Matches.begin() + 1);
2255 assert(Matches[0]->getNumParams() == NumArgs &&
2256 "found an unexpected usual deallocation function");
2259 assert(Matches.size() == 1 &&
2260 "unexpectedly have multiple usual deallocation functions");
2261 return Matches.front();
2264 bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
2265 DeclarationName Name,
2266 FunctionDecl* &Operator, bool Diagnose) {
2267 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
2268 // Try to find operator delete/operator delete[] in class scope.
2269 LookupQualifiedName(Found, RD);
2271 if (Found.isAmbiguous())
2274 Found.suppressDiagnostics();
2276 SmallVector<DeclAccessPair,4> Matches;
2277 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end();
2279 NamedDecl *ND = (*F)->getUnderlyingDecl();
2281 // Ignore template operator delete members from the check for a usual
2282 // deallocation function.
2283 if (isa<FunctionTemplateDecl>(ND))
2286 if (cast<CXXMethodDecl>(ND)->isUsualDeallocationFunction())
2287 Matches.push_back(F.getPair());
2290 // There's exactly one suitable operator; pick it.
2291 if (Matches.size() == 1) {
2292 Operator = cast<CXXMethodDecl>(Matches[0]->getUnderlyingDecl());
2294 if (Operator->isDeleted()) {
2296 Diag(StartLoc, diag::err_deleted_function_use);
2297 NoteDeletedFunction(Operator);
2302 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(),
2303 Matches[0], Diagnose) == AR_inaccessible)
2308 // We found multiple suitable operators; complain about the ambiguity.
2309 } else if (!Matches.empty()) {
2311 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found)
2314 for (SmallVectorImpl<DeclAccessPair>::iterator
2315 F = Matches.begin(), FEnd = Matches.end(); F != FEnd; ++F)
2316 Diag((*F)->getUnderlyingDecl()->getLocation(),
2317 diag::note_member_declared_here) << Name;
2322 // We did find operator delete/operator delete[] declarations, but
2323 // none of them were suitable.
2324 if (!Found.empty()) {
2326 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found)
2329 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end();
2331 Diag((*F)->getUnderlyingDecl()->getLocation(),
2332 diag::note_member_declared_here) << Name;
2342 /// \brief Checks whether delete-expression, and new-expression used for
2343 /// initializing deletee have the same array form.
2344 class MismatchingNewDeleteDetector {
2346 enum MismatchResult {
2347 /// Indicates that there is no mismatch or a mismatch cannot be proven.
2349 /// Indicates that variable is initialized with mismatching form of \a new.
2351 /// Indicates that member is initialized with mismatching form of \a new.
2352 MemberInitMismatches,
2353 /// Indicates that 1 or more constructors' definitions could not been
2354 /// analyzed, and they will be checked again at the end of translation unit.
2358 /// \param EndOfTU True, if this is the final analysis at the end of
2359 /// translation unit. False, if this is the initial analysis at the point
2360 /// delete-expression was encountered.
2361 explicit MismatchingNewDeleteDetector(bool EndOfTU)
2362 : IsArrayForm(false), Field(nullptr), EndOfTU(EndOfTU),
2363 HasUndefinedConstructors(false) {}
2365 /// \brief Checks whether pointee of a delete-expression is initialized with
2366 /// matching form of new-expression.
2368 /// If return value is \c VarInitMismatches or \c MemberInitMismatches at the
2369 /// point where delete-expression is encountered, then a warning will be
2370 /// issued immediately. If return value is \c AnalyzeLater at the point where
2371 /// delete-expression is seen, then member will be analyzed at the end of
2372 /// translation unit. \c AnalyzeLater is returned iff at least one constructor
2373 /// couldn't be analyzed. If at least one constructor initializes the member
2374 /// with matching type of new, the return value is \c NoMismatch.
2375 MismatchResult analyzeDeleteExpr(const CXXDeleteExpr *DE);
2376 /// \brief Analyzes a class member.
2377 /// \param Field Class member to analyze.
2378 /// \param DeleteWasArrayForm Array form-ness of the delete-expression used
2379 /// for deleting the \p Field.
2380 MismatchResult analyzeField(FieldDecl *Field, bool DeleteWasArrayForm);
2381 /// List of mismatching new-expressions used for initialization of the pointee
2382 llvm::SmallVector<const CXXNewExpr *, 4> NewExprs;
2383 /// Indicates whether delete-expression was in array form.
2389 /// \brief Indicates that there is at least one constructor without body.
2390 bool HasUndefinedConstructors;
2391 /// \brief Returns \c CXXNewExpr from given initialization expression.
2392 /// \param E Expression used for initializing pointee in delete-expression.
2393 /// E can be a single-element \c InitListExpr consisting of new-expression.
2394 const CXXNewExpr *getNewExprFromInitListOrExpr(const Expr *E);
2395 /// \brief Returns whether member is initialized with mismatching form of
2396 /// \c new either by the member initializer or in-class initialization.
2398 /// If bodies of all constructors are not visible at the end of translation
2399 /// unit or at least one constructor initializes member with the matching
2400 /// form of \c new, mismatch cannot be proven, and this function will return
2402 MismatchResult analyzeMemberExpr(const MemberExpr *ME);
2403 /// \brief Returns whether variable is initialized with mismatching form of
2406 /// If variable is initialized with matching form of \c new or variable is not
2407 /// initialized with a \c new expression, this function will return true.
2408 /// If variable is initialized with mismatching form of \c new, returns false.
2409 /// \param D Variable to analyze.
2410 bool hasMatchingVarInit(const DeclRefExpr *D);
2411 /// \brief Checks whether the constructor initializes pointee with mismatching
2414 /// Returns true, if member is initialized with matching form of \c new in
2415 /// member initializer list. Returns false, if member is initialized with the
2416 /// matching form of \c new in this constructor's initializer or given
2417 /// constructor isn't defined at the point where delete-expression is seen, or
2418 /// member isn't initialized by the constructor.
2419 bool hasMatchingNewInCtor(const CXXConstructorDecl *CD);
2420 /// \brief Checks whether member is initialized with matching form of
2421 /// \c new in member initializer list.
2422 bool hasMatchingNewInCtorInit(const CXXCtorInitializer *CI);
2423 /// Checks whether member is initialized with mismatching form of \c new by
2424 /// in-class initializer.
2425 MismatchResult analyzeInClassInitializer();
2429 MismatchingNewDeleteDetector::MismatchResult
2430 MismatchingNewDeleteDetector::analyzeDeleteExpr(const CXXDeleteExpr *DE) {
2432 assert(DE && "Expected delete-expression");
2433 IsArrayForm = DE->isArrayForm();
2434 const Expr *E = DE->getArgument()->IgnoreParenImpCasts();
2435 if (const MemberExpr *ME = dyn_cast<const MemberExpr>(E)) {
2436 return analyzeMemberExpr(ME);
2437 } else if (const DeclRefExpr *D = dyn_cast<const DeclRefExpr>(E)) {
2438 if (!hasMatchingVarInit(D))
2439 return VarInitMismatches;
2445 MismatchingNewDeleteDetector::getNewExprFromInitListOrExpr(const Expr *E) {
2446 assert(E != nullptr && "Expected a valid initializer expression");
2447 E = E->IgnoreParenImpCasts();
2448 if (const InitListExpr *ILE = dyn_cast<const InitListExpr>(E)) {
2449 if (ILE->getNumInits() == 1)
2450 E = dyn_cast<const CXXNewExpr>(ILE->getInit(0)->IgnoreParenImpCasts());
2453 return dyn_cast_or_null<const CXXNewExpr>(E);
2456 bool MismatchingNewDeleteDetector::hasMatchingNewInCtorInit(
2457 const CXXCtorInitializer *CI) {
2458 const CXXNewExpr *NE = nullptr;
2459 if (Field == CI->getMember() &&
2460 (NE = getNewExprFromInitListOrExpr(CI->getInit()))) {
2461 if (NE->isArray() == IsArrayForm)
2464 NewExprs.push_back(NE);
2469 bool MismatchingNewDeleteDetector::hasMatchingNewInCtor(
2470 const CXXConstructorDecl *CD) {
2471 if (CD->isImplicit())
2473 const FunctionDecl *Definition = CD;
2474 if (!CD->isThisDeclarationADefinition() && !CD->isDefined(Definition)) {
2475 HasUndefinedConstructors = true;
2478 for (const auto *CI : cast<const CXXConstructorDecl>(Definition)->inits()) {
2479 if (hasMatchingNewInCtorInit(CI))
2485 MismatchingNewDeleteDetector::MismatchResult
2486 MismatchingNewDeleteDetector::analyzeInClassInitializer() {
2487 assert(Field != nullptr && "This should be called only for members");
2488 const Expr *InitExpr = Field->getInClassInitializer();
2490 return EndOfTU ? NoMismatch : AnalyzeLater;
2491 if (const CXXNewExpr *NE = getNewExprFromInitListOrExpr(InitExpr)) {
2492 if (NE->isArray() != IsArrayForm) {
2493 NewExprs.push_back(NE);
2494 return MemberInitMismatches;
2500 MismatchingNewDeleteDetector::MismatchResult
2501 MismatchingNewDeleteDetector::analyzeField(FieldDecl *Field,
2502 bool DeleteWasArrayForm) {
2503 assert(Field != nullptr && "Analysis requires a valid class member.");
2504 this->Field = Field;
2505 IsArrayForm = DeleteWasArrayForm;
2506 const CXXRecordDecl *RD = cast<const CXXRecordDecl>(Field->getParent());
2507 for (const auto *CD : RD->ctors()) {
2508 if (hasMatchingNewInCtor(CD))
2511 if (HasUndefinedConstructors)
2512 return EndOfTU ? NoMismatch : AnalyzeLater;
2513 if (!NewExprs.empty())
2514 return MemberInitMismatches;
2515 return Field->hasInClassInitializer() ? analyzeInClassInitializer()
2519 MismatchingNewDeleteDetector::MismatchResult
2520 MismatchingNewDeleteDetector::analyzeMemberExpr(const MemberExpr *ME) {
2521 assert(ME != nullptr && "Expected a member expression");
2522 if (FieldDecl *F = dyn_cast<FieldDecl>(ME->getMemberDecl()))
2523 return analyzeField(F, IsArrayForm);
2527 bool MismatchingNewDeleteDetector::hasMatchingVarInit(const DeclRefExpr *D) {
2528 const CXXNewExpr *NE = nullptr;
2529 if (const VarDecl *VD = dyn_cast<const VarDecl>(D->getDecl())) {
2530 if (VD->hasInit() && (NE = getNewExprFromInitListOrExpr(VD->getInit())) &&
2531 NE->isArray() != IsArrayForm) {
2532 NewExprs.push_back(NE);
2535 return NewExprs.empty();
2539 DiagnoseMismatchedNewDelete(Sema &SemaRef, SourceLocation DeleteLoc,
2540 const MismatchingNewDeleteDetector &Detector) {
2541 SourceLocation EndOfDelete = SemaRef.getLocForEndOfToken(DeleteLoc);
2543 if (!Detector.IsArrayForm)
2544 H = FixItHint::CreateInsertion(EndOfDelete, "[]");
2546 SourceLocation RSquare = Lexer::findLocationAfterToken(
2547 DeleteLoc, tok::l_square, SemaRef.getSourceManager(),
2548 SemaRef.getLangOpts(), true);
2549 if (RSquare.isValid())
2550 H = FixItHint::CreateRemoval(SourceRange(EndOfDelete, RSquare));
2552 SemaRef.Diag(DeleteLoc, diag::warn_mismatched_delete_new)
2553 << Detector.IsArrayForm << H;
2555 for (const auto *NE : Detector.NewExprs)
2556 SemaRef.Diag(NE->getExprLoc(), diag::note_allocated_here)
2557 << Detector.IsArrayForm;
2560 void Sema::AnalyzeDeleteExprMismatch(const CXXDeleteExpr *DE) {
2561 if (Diags.isIgnored(diag::warn_mismatched_delete_new, SourceLocation()))
2563 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/false);
2564 switch (Detector.analyzeDeleteExpr(DE)) {
2565 case MismatchingNewDeleteDetector::VarInitMismatches:
2566 case MismatchingNewDeleteDetector::MemberInitMismatches: {
2567 DiagnoseMismatchedNewDelete(*this, DE->getLocStart(), Detector);
2570 case MismatchingNewDeleteDetector::AnalyzeLater: {
2571 DeleteExprs[Detector.Field].push_back(
2572 std::make_pair(DE->getLocStart(), DE->isArrayForm()));
2575 case MismatchingNewDeleteDetector::NoMismatch:
2580 void Sema::AnalyzeDeleteExprMismatch(FieldDecl *Field, SourceLocation DeleteLoc,
2581 bool DeleteWasArrayForm) {
2582 MismatchingNewDeleteDetector Detector(/*EndOfTU=*/true);
2583 switch (Detector.analyzeField(Field, DeleteWasArrayForm)) {
2584 case MismatchingNewDeleteDetector::VarInitMismatches:
2585 llvm_unreachable("This analysis should have been done for class members.");
2586 case MismatchingNewDeleteDetector::AnalyzeLater:
2587 llvm_unreachable("Analysis cannot be postponed any point beyond end of "
2588 "translation unit.");
2589 case MismatchingNewDeleteDetector::MemberInitMismatches:
2590 DiagnoseMismatchedNewDelete(*this, DeleteLoc, Detector);
2592 case MismatchingNewDeleteDetector::NoMismatch:
2597 /// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in:
2598 /// @code ::delete ptr; @endcode
2600 /// @code delete [] ptr; @endcode
2602 Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
2603 bool ArrayForm, Expr *ExE) {
2604 // C++ [expr.delete]p1:
2605 // The operand shall have a pointer type, or a class type having a single
2606 // non-explicit conversion function to a pointer type. The result has type
2609 // DR599 amends "pointer type" to "pointer to object type" in both cases.
2611 ExprResult Ex = ExE;
2612 FunctionDecl *OperatorDelete = nullptr;
2613 bool ArrayFormAsWritten = ArrayForm;
2614 bool UsualArrayDeleteWantsSize = false;
2616 if (!Ex.get()->isTypeDependent()) {
2617 // Perform lvalue-to-rvalue cast, if needed.
2618 Ex = DefaultLvalueConversion(Ex.get());
2622 QualType Type = Ex.get()->getType();
2624 class DeleteConverter : public ContextualImplicitConverter {
2626 DeleteConverter() : ContextualImplicitConverter(false, true) {}
2628 bool match(QualType ConvType) override {
2629 // FIXME: If we have an operator T* and an operator void*, we must pick
2631 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
2632 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType())
2637 SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
2638 QualType T) override {
2639 return S.Diag(Loc, diag::err_delete_operand) << T;
2642 SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
2643 QualType T) override {
2644 return S.Diag(Loc, diag::err_delete_incomplete_class_type) << T;
2647 SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
2649 QualType ConvTy) override {
2650 return S.Diag(Loc, diag::err_delete_explicit_conversion) << T << ConvTy;
2653 SemaDiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
2654 QualType ConvTy) override {
2655 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
2659 SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
2660 QualType T) override {
2661 return S.Diag(Loc, diag::err_ambiguous_delete_operand) << T;
2664 SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
2665 QualType ConvTy) override {
2666 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
2670 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
2672 QualType ConvTy) override {
2673 llvm_unreachable("conversion functions are permitted");
2677 Ex = PerformContextualImplicitConversion(StartLoc, Ex.get(), Converter);
2680 Type = Ex.get()->getType();
2681 if (!Converter.match(Type))
2682 // FIXME: PerformContextualImplicitConversion should return ExprError
2683 // itself in this case.
2686 QualType Pointee = Type->getAs<PointerType>()->getPointeeType();
2687 QualType PointeeElem = Context.getBaseElementType(Pointee);
2689 if (unsigned AddressSpace = Pointee.getAddressSpace())
2690 return Diag(Ex.get()->getLocStart(),
2691 diag::err_address_space_qualified_delete)
2692 << Pointee.getUnqualifiedType() << AddressSpace;
2694 CXXRecordDecl *PointeeRD = nullptr;
2695 if (Pointee->isVoidType() && !isSFINAEContext()) {
2696 // The C++ standard bans deleting a pointer to a non-object type, which
2697 // effectively bans deletion of "void*". However, most compilers support
2698 // this, so we treat it as a warning unless we're in a SFINAE context.
2699 Diag(StartLoc, diag::ext_delete_void_ptr_operand)
2700 << Type << Ex.get()->getSourceRange();
2701 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) {
2702 return ExprError(Diag(StartLoc, diag::err_delete_operand)
2703 << Type << Ex.get()->getSourceRange());
2704 } else if (!Pointee->isDependentType()) {
2705 if (!RequireCompleteType(StartLoc, Pointee,
2706 diag::warn_delete_incomplete, Ex.get())) {
2707 if (const RecordType *RT = PointeeElem->getAs<RecordType>())
2708 PointeeRD = cast<CXXRecordDecl>(RT->getDecl());
2712 if (Pointee->isArrayType() && !ArrayForm) {
2713 Diag(StartLoc, diag::warn_delete_array_type)
2714 << Type << Ex.get()->getSourceRange()
2715 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(StartLoc), "[]");
2719 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
2720 ArrayForm ? OO_Array_Delete : OO_Delete);
2724 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName,
2728 // If we're allocating an array of records, check whether the
2729 // usual operator delete[] has a size_t parameter.
2731 // If the user specifically asked to use the global allocator,
2732 // we'll need to do the lookup into the class.
2734 UsualArrayDeleteWantsSize =
2735 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem);
2737 // Otherwise, the usual operator delete[] should be the
2738 // function we just found.
2739 else if (OperatorDelete && isa<CXXMethodDecl>(OperatorDelete))
2740 UsualArrayDeleteWantsSize = (OperatorDelete->getNumParams() == 2);
2743 if (!PointeeRD->hasIrrelevantDestructor())
2744 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
2745 MarkFunctionReferenced(StartLoc,
2746 const_cast<CXXDestructorDecl*>(Dtor));
2747 if (DiagnoseUseOfDecl(Dtor, StartLoc))
2751 // C++ [expr.delete]p3:
2752 // In the first alternative (delete object), if the static type of the
2753 // object to be deleted is different from its dynamic type, the static
2754 // type shall be a base class of the dynamic type of the object to be
2755 // deleted and the static type shall have a virtual destructor or the
2756 // behavior is undefined.
2758 // Note: a final class cannot be derived from, no issue there
2759 if (PointeeRD->isPolymorphic() && !PointeeRD->hasAttr<FinalAttr>()) {
2760 CXXDestructorDecl *dtor = PointeeRD->getDestructor();
2761 if (dtor && !dtor->isVirtual()) {
2762 if (PointeeRD->isAbstract()) {
2763 // If the class is abstract, we warn by default, because we're
2764 // sure the code has undefined behavior.
2765 Diag(StartLoc, diag::warn_delete_abstract_non_virtual_dtor)
2767 } else if (!ArrayForm) {
2768 // Otherwise, if this is not an array delete, it's a bit suspect,
2769 // but not necessarily wrong.
2770 Diag(StartLoc, diag::warn_delete_non_virtual_dtor) << PointeeElem;
2777 if (!OperatorDelete)
2778 // Look for a global declaration.
2779 OperatorDelete = FindUsualDeallocationFunction(
2780 StartLoc, !RequireCompleteType(StartLoc, Pointee, 0) &&
2781 (!ArrayForm || UsualArrayDeleteWantsSize ||
2782 Pointee.isDestructedType()),
2785 MarkFunctionReferenced(StartLoc, OperatorDelete);
2787 // Check access and ambiguity of operator delete and destructor.
2789 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
2790 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor,
2791 PDiag(diag::err_access_dtor) << PointeeElem);
2796 CXXDeleteExpr *Result = new (Context) CXXDeleteExpr(
2797 Context.VoidTy, UseGlobal, ArrayForm, ArrayFormAsWritten,
2798 UsualArrayDeleteWantsSize, OperatorDelete, Ex.get(), StartLoc);
2799 AnalyzeDeleteExprMismatch(Result);
2803 /// \brief Check the use of the given variable as a C++ condition in an if,
2804 /// while, do-while, or switch statement.
2805 ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar,
2806 SourceLocation StmtLoc,
2807 bool ConvertToBoolean) {
2808 if (ConditionVar->isInvalidDecl())
2811 QualType T = ConditionVar->getType();
2813 // C++ [stmt.select]p2:
2814 // The declarator shall not specify a function or an array.
2815 if (T->isFunctionType())
2816 return ExprError(Diag(ConditionVar->getLocation(),
2817 diag::err_invalid_use_of_function_type)
2818 << ConditionVar->getSourceRange());
2819 else if (T->isArrayType())
2820 return ExprError(Diag(ConditionVar->getLocation(),
2821 diag::err_invalid_use_of_array_type)
2822 << ConditionVar->getSourceRange());
2824 ExprResult Condition = DeclRefExpr::Create(
2825 Context, NestedNameSpecifierLoc(), SourceLocation(), ConditionVar,
2826 /*enclosing*/ false, ConditionVar->getLocation(),
2827 ConditionVar->getType().getNonReferenceType(), VK_LValue);
2829 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get()));
2831 if (ConvertToBoolean) {
2832 Condition = CheckBooleanCondition(Condition.get(), StmtLoc);
2833 if (Condition.isInvalid())
2840 /// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
2841 ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr) {
2843 // The value of a condition that is an initialized declaration in a statement
2844 // other than a switch statement is the value of the declared variable
2845 // implicitly converted to type bool. If that conversion is ill-formed, the
2846 // program is ill-formed.
2847 // The value of a condition that is an expression is the value of the
2848 // expression, implicitly converted to bool.
2850 return PerformContextuallyConvertToBool(CondExpr);
2853 /// Helper function to determine whether this is the (deprecated) C++
2854 /// conversion from a string literal to a pointer to non-const char or
2855 /// non-const wchar_t (for narrow and wide string literals,
2858 Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) {
2859 // Look inside the implicit cast, if it exists.
2860 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From))
2861 From = Cast->getSubExpr();
2863 // A string literal (2.13.4) that is not a wide string literal can
2864 // be converted to an rvalue of type "pointer to char"; a wide
2865 // string literal can be converted to an rvalue of type "pointer
2866 // to wchar_t" (C++ 4.2p2).
2867 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens()))
2868 if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
2869 if (const BuiltinType *ToPointeeType
2870 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
2871 // This conversion is considered only when there is an
2872 // explicit appropriate pointer target type (C++ 4.2p2).
2873 if (!ToPtrType->getPointeeType().hasQualifiers()) {
2874 switch (StrLit->getKind()) {
2875 case StringLiteral::UTF8:
2876 case StringLiteral::UTF16:
2877 case StringLiteral::UTF32:
2878 // We don't allow UTF literals to be implicitly converted
2880 case StringLiteral::Ascii:
2881 return (ToPointeeType->getKind() == BuiltinType::Char_U ||
2882 ToPointeeType->getKind() == BuiltinType::Char_S);
2883 case StringLiteral::Wide:
2884 return ToPointeeType->isWideCharType();
2892 static ExprResult BuildCXXCastArgument(Sema &S,
2893 SourceLocation CastLoc,
2896 CXXMethodDecl *Method,
2897 DeclAccessPair FoundDecl,
2898 bool HadMultipleCandidates,
2901 default: llvm_unreachable("Unhandled cast kind!");
2902 case CK_ConstructorConversion: {
2903 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method);
2904 SmallVector<Expr*, 8> ConstructorArgs;
2906 if (S.RequireNonAbstractType(CastLoc, Ty,
2907 diag::err_allocation_of_abstract_type))
2910 if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs))
2913 S.CheckConstructorAccess(CastLoc, Constructor,
2914 InitializedEntity::InitializeTemporary(Ty),
2915 Constructor->getAccess());
2916 if (S.DiagnoseUseOfDecl(Method, CastLoc))
2919 ExprResult Result = S.BuildCXXConstructExpr(
2920 CastLoc, Ty, cast<CXXConstructorDecl>(Method),
2921 ConstructorArgs, HadMultipleCandidates,
2922 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
2923 CXXConstructExpr::CK_Complete, SourceRange());
2924 if (Result.isInvalid())
2927 return S.MaybeBindToTemporary(Result.getAs<Expr>());
2930 case CK_UserDefinedConversion: {
2931 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
2933 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ nullptr, FoundDecl);
2934 if (S.DiagnoseUseOfDecl(Method, CastLoc))
2937 // Create an implicit call expr that calls it.
2938 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method);
2939 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv,
2940 HadMultipleCandidates);
2941 if (Result.isInvalid())
2943 // Record usage of conversion in an implicit cast.
2944 Result = ImplicitCastExpr::Create(S.Context, Result.get()->getType(),
2945 CK_UserDefinedConversion, Result.get(),
2946 nullptr, Result.get()->getValueKind());
2948 return S.MaybeBindToTemporary(Result.get());
2953 /// PerformImplicitConversion - Perform an implicit conversion of the
2954 /// expression From to the type ToType using the pre-computed implicit
2955 /// conversion sequence ICS. Returns the converted
2956 /// expression. Action is the kind of conversion we're performing,
2957 /// used in the error message.
2959 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
2960 const ImplicitConversionSequence &ICS,
2961 AssignmentAction Action,
2962 CheckedConversionKind CCK) {
2963 switch (ICS.getKind()) {
2964 case ImplicitConversionSequence::StandardConversion: {
2965 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard,
2967 if (Res.isInvalid())
2973 case ImplicitConversionSequence::UserDefinedConversion: {
2975 FunctionDecl *FD = ICS.UserDefined.ConversionFunction;
2977 QualType BeforeToType;
2978 assert(FD && "no conversion function for user-defined conversion seq");
2979 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) {
2980 CastKind = CK_UserDefinedConversion;
2982 // If the user-defined conversion is specified by a conversion function,
2983 // the initial standard conversion sequence converts the source type to
2984 // the implicit object parameter of the conversion function.
2985 BeforeToType = Context.getTagDeclType(Conv->getParent());
2987 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD);
2988 CastKind = CK_ConstructorConversion;
2989 // Do no conversion if dealing with ... for the first conversion.
2990 if (!ICS.UserDefined.EllipsisConversion) {
2991 // If the user-defined conversion is specified by a constructor, the
2992 // initial standard conversion sequence converts the source type to
2993 // the type required by the argument of the constructor
2994 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType();
2997 // Watch out for ellipsis conversion.
2998 if (!ICS.UserDefined.EllipsisConversion) {
3000 PerformImplicitConversion(From, BeforeToType,
3001 ICS.UserDefined.Before, AA_Converting,
3003 if (Res.isInvalid())
3009 = BuildCXXCastArgument(*this,
3010 From->getLocStart(),
3011 ToType.getNonReferenceType(),
3012 CastKind, cast<CXXMethodDecl>(FD),
3013 ICS.UserDefined.FoundConversionFunction,
3014 ICS.UserDefined.HadMultipleCandidates,
3017 if (CastArg.isInvalid())
3020 From = CastArg.get();
3022 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
3023 AA_Converting, CCK);
3026 case ImplicitConversionSequence::AmbiguousConversion:
3027 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(),
3028 PDiag(diag::err_typecheck_ambiguous_condition)
3029 << From->getSourceRange());
3032 case ImplicitConversionSequence::EllipsisConversion:
3033 llvm_unreachable("Cannot perform an ellipsis conversion");
3035 case ImplicitConversionSequence::BadConversion:
3039 // Everything went well.
3043 /// PerformImplicitConversion - Perform an implicit conversion of the
3044 /// expression From to the type ToType by following the standard
3045 /// conversion sequence SCS. Returns the converted
3046 /// expression. Flavor is the context in which we're performing this
3047 /// conversion, for use in error messages.
3049 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
3050 const StandardConversionSequence& SCS,
3051 AssignmentAction Action,
3052 CheckedConversionKind CCK) {
3053 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast);
3055 // Overall FIXME: we are recomputing too many types here and doing far too
3056 // much extra work. What this means is that we need to keep track of more
3057 // information that is computed when we try the implicit conversion initially,
3058 // so that we don't need to recompute anything here.
3059 QualType FromType = From->getType();
3061 if (SCS.CopyConstructor) {
3062 // FIXME: When can ToType be a reference type?
3063 assert(!ToType->isReferenceType());
3064 if (SCS.Second == ICK_Derived_To_Base) {
3065 SmallVector<Expr*, 8> ConstructorArgs;
3066 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor),
3067 From, /*FIXME:ConstructLoc*/SourceLocation(),
3070 return BuildCXXConstructExpr(
3071 /*FIXME:ConstructLoc*/ SourceLocation(), ToType, SCS.CopyConstructor,
3072 ConstructorArgs, /*HadMultipleCandidates*/ false,
3073 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3074 CXXConstructExpr::CK_Complete, SourceRange());
3076 return BuildCXXConstructExpr(
3077 /*FIXME:ConstructLoc*/ SourceLocation(), ToType, SCS.CopyConstructor,
3078 From, /*HadMultipleCandidates*/ false,
3079 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
3080 CXXConstructExpr::CK_Complete, SourceRange());
3083 // Resolve overloaded function references.
3084 if (Context.hasSameType(FromType, Context.OverloadTy)) {
3085 DeclAccessPair Found;
3086 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType,
3091 if (DiagnoseUseOfDecl(Fn, From->getLocStart()))
3094 From = FixOverloadedFunctionReference(From, Found, Fn);
3095 FromType = From->getType();
3098 // If we're converting to an atomic type, first convert to the corresponding
3100 QualType ToAtomicType;
3101 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) {
3102 ToAtomicType = ToType;
3103 ToType = ToAtomic->getValueType();
3106 // Perform the first implicit conversion.
3107 switch (SCS.First) {
3109 if (const AtomicType *FromAtomic = FromType->getAs<AtomicType>()) {
3110 FromType = FromAtomic->getValueType().getUnqualifiedType();
3111 From = ImplicitCastExpr::Create(Context, FromType, CK_AtomicToNonAtomic,
3112 From, /*BasePath=*/nullptr, VK_RValue);
3116 case ICK_Lvalue_To_Rvalue: {
3117 assert(From->getObjectKind() != OK_ObjCProperty);
3118 ExprResult FromRes = DefaultLvalueConversion(From);
3119 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!");
3120 From = FromRes.get();
3121 FromType = From->getType();
3125 case ICK_Array_To_Pointer:
3126 FromType = Context.getArrayDecayedType(FromType);
3127 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay,
3128 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3131 case ICK_Function_To_Pointer:
3132 FromType = Context.getPointerType(FromType);
3133 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay,
3134 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3138 llvm_unreachable("Improper first standard conversion");
3141 // Perform the second implicit conversion
3142 switch (SCS.Second) {
3144 // C++ [except.spec]p5:
3145 // [For] assignment to and initialization of pointers to functions,
3146 // pointers to member functions, and references to functions: the
3147 // target entity shall allow at least the exceptions allowed by the
3148 // source value in the assignment or initialization.
3151 case AA_Initializing:
3152 // Note, function argument passing and returning are initialization.
3156 case AA_Passing_CFAudited:
3157 if (CheckExceptionSpecCompatibility(From, ToType))
3163 // Casts and implicit conversions are not initialization, so are not
3164 // checked for exception specification mismatches.
3167 // Nothing else to do.
3170 case ICK_NoReturn_Adjustment:
3171 // If both sides are functions (or pointers/references to them), there could
3172 // be incompatible exception declarations.
3173 if (CheckExceptionSpecCompatibility(From, ToType))
3176 From = ImpCastExprToType(From, ToType, CK_NoOp,
3177 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3180 case ICK_Integral_Promotion:
3181 case ICK_Integral_Conversion:
3182 if (ToType->isBooleanType()) {
3183 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() &&
3184 SCS.Second == ICK_Integral_Promotion &&
3185 "only enums with fixed underlying type can promote to bool");
3186 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean,
3187 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3189 From = ImpCastExprToType(From, ToType, CK_IntegralCast,
3190 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3194 case ICK_Floating_Promotion:
3195 case ICK_Floating_Conversion:
3196 From = ImpCastExprToType(From, ToType, CK_FloatingCast,
3197 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3200 case ICK_Complex_Promotion:
3201 case ICK_Complex_Conversion: {
3202 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType();
3203 QualType ToEl = ToType->getAs<ComplexType>()->getElementType();
3205 if (FromEl->isRealFloatingType()) {
3206 if (ToEl->isRealFloatingType())
3207 CK = CK_FloatingComplexCast;
3209 CK = CK_FloatingComplexToIntegralComplex;
3210 } else if (ToEl->isRealFloatingType()) {
3211 CK = CK_IntegralComplexToFloatingComplex;
3213 CK = CK_IntegralComplexCast;
3215 From = ImpCastExprToType(From, ToType, CK,
3216 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3220 case ICK_Floating_Integral:
3221 if (ToType->isRealFloatingType())
3222 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating,
3223 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3225 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral,
3226 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3229 case ICK_Compatible_Conversion:
3230 From = ImpCastExprToType(From, ToType, CK_NoOp,
3231 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3234 case ICK_Writeback_Conversion:
3235 case ICK_Pointer_Conversion: {
3236 if (SCS.IncompatibleObjC && Action != AA_Casting) {
3237 // Diagnose incompatible Objective-C conversions
3238 if (Action == AA_Initializing || Action == AA_Assigning)
3239 Diag(From->getLocStart(),
3240 diag::ext_typecheck_convert_incompatible_pointer)
3241 << ToType << From->getType() << Action
3242 << From->getSourceRange() << 0;
3244 Diag(From->getLocStart(),
3245 diag::ext_typecheck_convert_incompatible_pointer)
3246 << From->getType() << ToType << Action
3247 << From->getSourceRange() << 0;
3249 if (From->getType()->isObjCObjectPointerType() &&
3250 ToType->isObjCObjectPointerType())
3251 EmitRelatedResultTypeNote(From);
3253 else if (getLangOpts().ObjCAutoRefCount &&
3254 !CheckObjCARCUnavailableWeakConversion(ToType,
3256 if (Action == AA_Initializing)
3257 Diag(From->getLocStart(),
3258 diag::err_arc_weak_unavailable_assign);
3260 Diag(From->getLocStart(),
3261 diag::err_arc_convesion_of_weak_unavailable)
3262 << (Action == AA_Casting) << From->getType() << ToType
3263 << From->getSourceRange();
3266 CastKind Kind = CK_Invalid;
3267 CXXCastPath BasePath;
3268 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle))
3271 // Make sure we extend blocks if necessary.
3272 // FIXME: doing this here is really ugly.
3273 if (Kind == CK_BlockPointerToObjCPointerCast) {
3274 ExprResult E = From;
3275 (void) PrepareCastToObjCObjectPointer(E);
3278 if (getLangOpts().ObjCAutoRefCount)
3279 CheckObjCARCConversion(SourceRange(), ToType, From, CCK);
3280 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
3285 case ICK_Pointer_Member: {
3286 CastKind Kind = CK_Invalid;
3287 CXXCastPath BasePath;
3288 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle))
3290 if (CheckExceptionSpecCompatibility(From, ToType))
3293 // We may not have been able to figure out what this member pointer resolved
3294 // to up until this exact point. Attempt to lock-in it's inheritance model.
3295 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
3296 RequireCompleteType(From->getExprLoc(), From->getType(), 0);
3297 RequireCompleteType(From->getExprLoc(), ToType, 0);
3300 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
3305 case ICK_Boolean_Conversion:
3306 // Perform half-to-boolean conversion via float.
3307 if (From->getType()->isHalfType()) {
3308 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).get();
3309 FromType = Context.FloatTy;
3312 From = ImpCastExprToType(From, Context.BoolTy,
3313 ScalarTypeToBooleanCastKind(FromType),
3314 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3317 case ICK_Derived_To_Base: {
3318 CXXCastPath BasePath;
3319 if (CheckDerivedToBaseConversion(From->getType(),
3320 ToType.getNonReferenceType(),
3321 From->getLocStart(),
3322 From->getSourceRange(),
3327 From = ImpCastExprToType(From, ToType.getNonReferenceType(),
3328 CK_DerivedToBase, From->getValueKind(),
3329 &BasePath, CCK).get();
3333 case ICK_Vector_Conversion:
3334 From = ImpCastExprToType(From, ToType, CK_BitCast,
3335 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3338 case ICK_Vector_Splat:
3339 // Vector splat from any arithmetic type to a vector.
3340 // Cast to the element type.
3342 QualType elType = ToType->getAs<ExtVectorType>()->getElementType();
3343 if (elType != From->getType()) {
3344 ExprResult E = From;
3345 From = ImpCastExprToType(From, elType,
3346 PrepareScalarCast(E, elType)).get();
3348 From = ImpCastExprToType(From, ToType, CK_VectorSplat,
3349 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3353 case ICK_Complex_Real:
3354 // Case 1. x -> _Complex y
3355 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) {
3356 QualType ElType = ToComplex->getElementType();
3357 bool isFloatingComplex = ElType->isRealFloatingType();
3360 if (Context.hasSameUnqualifiedType(ElType, From->getType())) {
3362 } else if (From->getType()->isRealFloatingType()) {
3363 From = ImpCastExprToType(From, ElType,
3364 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).get();
3366 assert(From->getType()->isIntegerType());
3367 From = ImpCastExprToType(From, ElType,
3368 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).get();
3371 From = ImpCastExprToType(From, ToType,
3372 isFloatingComplex ? CK_FloatingRealToComplex
3373 : CK_IntegralRealToComplex).get();
3375 // Case 2. _Complex x -> y
3377 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>();
3378 assert(FromComplex);
3380 QualType ElType = FromComplex->getElementType();
3381 bool isFloatingComplex = ElType->isRealFloatingType();
3384 From = ImpCastExprToType(From, ElType,
3385 isFloatingComplex ? CK_FloatingComplexToReal
3386 : CK_IntegralComplexToReal,
3387 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3390 if (Context.hasSameUnqualifiedType(ElType, ToType)) {
3392 } else if (ToType->isRealFloatingType()) {
3393 From = ImpCastExprToType(From, ToType,
3394 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating,
3395 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3397 assert(ToType->isIntegerType());
3398 From = ImpCastExprToType(From, ToType,
3399 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast,
3400 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3405 case ICK_Block_Pointer_Conversion: {
3406 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast,
3407 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3411 case ICK_TransparentUnionConversion: {
3412 ExprResult FromRes = From;
3413 Sema::AssignConvertType ConvTy =
3414 CheckTransparentUnionArgumentConstraints(ToType, FromRes);
3415 if (FromRes.isInvalid())
3417 From = FromRes.get();
3418 assert ((ConvTy == Sema::Compatible) &&
3419 "Improper transparent union conversion");
3424 case ICK_Zero_Event_Conversion:
3425 From = ImpCastExprToType(From, ToType,
3427 From->getValueKind()).get();
3430 case ICK_Lvalue_To_Rvalue:
3431 case ICK_Array_To_Pointer:
3432 case ICK_Function_To_Pointer:
3433 case ICK_Qualification:
3434 case ICK_Num_Conversion_Kinds:
3435 llvm_unreachable("Improper second standard conversion");
3438 switch (SCS.Third) {
3443 case ICK_Qualification: {
3444 // The qualification keeps the category of the inner expression, unless the
3445 // target type isn't a reference.
3446 ExprValueKind VK = ToType->isReferenceType() ?
3447 From->getValueKind() : VK_RValue;
3448 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context),
3449 CK_NoOp, VK, /*BasePath=*/nullptr, CCK).get();
3451 if (SCS.DeprecatedStringLiteralToCharPtr &&
3452 !getLangOpts().WritableStrings) {
3453 Diag(From->getLocStart(), getLangOpts().CPlusPlus11
3454 ? diag::ext_deprecated_string_literal_conversion
3455 : diag::warn_deprecated_string_literal_conversion)
3456 << ToType.getNonReferenceType();
3463 llvm_unreachable("Improper third standard conversion");
3466 // If this conversion sequence involved a scalar -> atomic conversion, perform
3467 // that conversion now.
3468 if (!ToAtomicType.isNull()) {
3469 assert(Context.hasSameType(
3470 ToAtomicType->castAs<AtomicType>()->getValueType(), From->getType()));
3471 From = ImpCastExprToType(From, ToAtomicType, CK_NonAtomicToAtomic,
3472 VK_RValue, nullptr, CCK).get();
3478 /// \brief Check the completeness of a type in a unary type trait.
3480 /// If the particular type trait requires a complete type, tries to complete
3481 /// it. If completing the type fails, a diagnostic is emitted and false
3482 /// returned. If completing the type succeeds or no completion was required,
3484 static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, TypeTrait UTT,
3487 // C++0x [meta.unary.prop]p3:
3488 // For all of the class templates X declared in this Clause, instantiating
3489 // that template with a template argument that is a class template
3490 // specialization may result in the implicit instantiation of the template
3491 // argument if and only if the semantics of X require that the argument
3492 // must be a complete type.
3493 // We apply this rule to all the type trait expressions used to implement
3494 // these class templates. We also try to follow any GCC documented behavior
3495 // in these expressions to ensure portability of standard libraries.
3497 default: llvm_unreachable("not a UTT");
3498 // is_complete_type somewhat obviously cannot require a complete type.
3499 case UTT_IsCompleteType:
3502 // These traits are modeled on the type predicates in C++0x
3503 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as
3504 // requiring a complete type, as whether or not they return true cannot be
3505 // impacted by the completeness of the type.
3507 case UTT_IsIntegral:
3508 case UTT_IsFloatingPoint:
3511 case UTT_IsLvalueReference:
3512 case UTT_IsRvalueReference:
3513 case UTT_IsMemberFunctionPointer:
3514 case UTT_IsMemberObjectPointer:
3518 case UTT_IsFunction:
3519 case UTT_IsReference:
3520 case UTT_IsArithmetic:
3521 case UTT_IsFundamental:
3524 case UTT_IsCompound:
3525 case UTT_IsMemberPointer:
3528 // These traits are modeled on type predicates in C++0x [meta.unary.prop]
3529 // which requires some of its traits to have the complete type. However,
3530 // the completeness of the type cannot impact these traits' semantics, and
3531 // so they don't require it. This matches the comments on these traits in
3534 case UTT_IsVolatile:
3536 case UTT_IsUnsigned:
3539 // C++0x [meta.unary.prop] Table 49 requires the following traits to be
3540 // applied to a complete type.
3542 case UTT_IsTriviallyCopyable:
3543 case UTT_IsStandardLayout:
3547 case UTT_IsPolymorphic:
3548 case UTT_IsAbstract:
3549 case UTT_IsInterfaceClass:
3550 case UTT_IsDestructible:
3551 case UTT_IsNothrowDestructible:
3554 // These traits require a complete type.
3558 // These trait expressions are designed to help implement predicates in
3559 // [meta.unary.prop] despite not being named the same. They are specified
3560 // by both GCC and the Embarcadero C++ compiler, and require the complete
3561 // type due to the overarching C++0x type predicates being implemented
3562 // requiring the complete type.
3563 case UTT_HasNothrowAssign:
3564 case UTT_HasNothrowMoveAssign:
3565 case UTT_HasNothrowConstructor:
3566 case UTT_HasNothrowCopy:
3567 case UTT_HasTrivialAssign:
3568 case UTT_HasTrivialMoveAssign:
3569 case UTT_HasTrivialDefaultConstructor:
3570 case UTT_HasTrivialMoveConstructor:
3571 case UTT_HasTrivialCopy:
3572 case UTT_HasTrivialDestructor:
3573 case UTT_HasVirtualDestructor:
3574 // Arrays of unknown bound are expressly allowed.
3575 QualType ElTy = ArgTy;
3576 if (ArgTy->isIncompleteArrayType())
3577 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType();
3579 // The void type is expressly allowed.
3580 if (ElTy->isVoidType())
3583 return !S.RequireCompleteType(
3584 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr);
3588 static bool HasNoThrowOperator(const RecordType *RT, OverloadedOperatorKind Op,
3589 Sema &Self, SourceLocation KeyLoc, ASTContext &C,
3590 bool (CXXRecordDecl::*HasTrivial)() const,
3591 bool (CXXRecordDecl::*HasNonTrivial)() const,
3592 bool (CXXMethodDecl::*IsDesiredOp)() const)
3594 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3595 if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)())
3598 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op);
3599 DeclarationNameInfo NameInfo(Name, KeyLoc);
3600 LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName);
3601 if (Self.LookupQualifiedName(Res, RD)) {
3602 bool FoundOperator = false;
3603 Res.suppressDiagnostics();
3604 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end();
3605 Op != OpEnd; ++Op) {
3606 if (isa<FunctionTemplateDecl>(*Op))
3609 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op);
3610 if((Operator->*IsDesiredOp)()) {
3611 FoundOperator = true;
3612 const FunctionProtoType *CPT =
3613 Operator->getType()->getAs<FunctionProtoType>();
3614 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
3615 if (!CPT || !CPT->isNothrow(C))
3619 return FoundOperator;
3624 static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
3625 SourceLocation KeyLoc, QualType T) {
3626 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
3628 ASTContext &C = Self.Context;
3630 default: llvm_unreachable("not a UTT");
3631 // Type trait expressions corresponding to the primary type category
3632 // predicates in C++0x [meta.unary.cat].
3634 return T->isVoidType();
3635 case UTT_IsIntegral:
3636 return T->isIntegralType(C);
3637 case UTT_IsFloatingPoint:
3638 return T->isFloatingType();
3640 return T->isArrayType();
3642 return T->isPointerType();
3643 case UTT_IsLvalueReference:
3644 return T->isLValueReferenceType();
3645 case UTT_IsRvalueReference:
3646 return T->isRValueReferenceType();
3647 case UTT_IsMemberFunctionPointer:
3648 return T->isMemberFunctionPointerType();
3649 case UTT_IsMemberObjectPointer:
3650 return T->isMemberDataPointerType();
3652 return T->isEnumeralType();
3654 return T->isUnionType();
3656 return T->isClassType() || T->isStructureType() || T->isInterfaceType();
3657 case UTT_IsFunction:
3658 return T->isFunctionType();
3660 // Type trait expressions which correspond to the convenient composition
3661 // predicates in C++0x [meta.unary.comp].
3662 case UTT_IsReference:
3663 return T->isReferenceType();
3664 case UTT_IsArithmetic:
3665 return T->isArithmeticType() && !T->isEnumeralType();
3666 case UTT_IsFundamental:
3667 return T->isFundamentalType();
3669 return T->isObjectType();
3671 // Note: semantic analysis depends on Objective-C lifetime types to be
3672 // considered scalar types. However, such types do not actually behave
3673 // like scalar types at run time (since they may require retain/release
3674 // operations), so we report them as non-scalar.
3675 if (T->isObjCLifetimeType()) {
3676 switch (T.getObjCLifetime()) {
3677 case Qualifiers::OCL_None:
3678 case Qualifiers::OCL_ExplicitNone:
3681 case Qualifiers::OCL_Strong:
3682 case Qualifiers::OCL_Weak:
3683 case Qualifiers::OCL_Autoreleasing:
3688 return T->isScalarType();
3689 case UTT_IsCompound:
3690 return T->isCompoundType();
3691 case UTT_IsMemberPointer:
3692 return T->isMemberPointerType();
3694 // Type trait expressions which correspond to the type property predicates
3695 // in C++0x [meta.unary.prop].
3697 return T.isConstQualified();
3698 case UTT_IsVolatile:
3699 return T.isVolatileQualified();
3701 return T.isTrivialType(Self.Context);
3702 case UTT_IsTriviallyCopyable:
3703 return T.isTriviallyCopyableType(Self.Context);
3704 case UTT_IsStandardLayout:
3705 return T->isStandardLayoutType();
3707 return T.isPODType(Self.Context);
3709 return T->isLiteralType(Self.Context);
3711 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3712 return !RD->isUnion() && RD->isEmpty();
3714 case UTT_IsPolymorphic:
3715 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3716 return RD->isPolymorphic();
3718 case UTT_IsAbstract:
3719 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3720 return RD->isAbstract();
3722 case UTT_IsInterfaceClass:
3723 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3724 return RD->isInterface();
3727 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3728 return RD->hasAttr<FinalAttr>();
3731 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3732 if (FinalAttr *FA = RD->getAttr<FinalAttr>())
3733 return FA->isSpelledAsSealed();
3736 return T->isSignedIntegerType();
3737 case UTT_IsUnsigned:
3738 return T->isUnsignedIntegerType();
3740 // Type trait expressions which query classes regarding their construction,
3741 // destruction, and copying. Rather than being based directly on the
3742 // related type predicates in the standard, they are specified by both
3743 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those
3746 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
3747 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
3749 // Note that these builtins do not behave as documented in g++: if a class
3750 // has both a trivial and a non-trivial special member of a particular kind,
3751 // they return false! For now, we emulate this behavior.
3752 // FIXME: This appears to be a g++ bug: more complex cases reveal that it
3753 // does not correctly compute triviality in the presence of multiple special
3754 // members of the same kind. Revisit this once the g++ bug is fixed.
3755 case UTT_HasTrivialDefaultConstructor:
3756 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3757 // If __is_pod (type) is true then the trait is true, else if type is
3758 // a cv class or union type (or array thereof) with a trivial default
3759 // constructor ([class.ctor]) then the trait is true, else it is false.
3760 if (T.isPODType(Self.Context))
3762 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
3763 return RD->hasTrivialDefaultConstructor() &&
3764 !RD->hasNonTrivialDefaultConstructor();
3766 case UTT_HasTrivialMoveConstructor:
3767 // This trait is implemented by MSVC 2012 and needed to parse the
3768 // standard library headers. Specifically this is used as the logic
3769 // behind std::is_trivially_move_constructible (20.9.4.3).
3770 if (T.isPODType(Self.Context))
3772 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
3773 return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor();
3775 case UTT_HasTrivialCopy:
3776 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3777 // If __is_pod (type) is true or type is a reference type then
3778 // the trait is true, else if type is a cv class or union type
3779 // with a trivial copy constructor ([class.copy]) then the trait
3780 // is true, else it is false.
3781 if (T.isPODType(Self.Context) || T->isReferenceType())
3783 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3784 return RD->hasTrivialCopyConstructor() &&
3785 !RD->hasNonTrivialCopyConstructor();
3787 case UTT_HasTrivialMoveAssign:
3788 // This trait is implemented by MSVC 2012 and needed to parse the
3789 // standard library headers. Specifically it is used as the logic
3790 // behind std::is_trivially_move_assignable (20.9.4.3)
3791 if (T.isPODType(Self.Context))
3793 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
3794 return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment();
3796 case UTT_HasTrivialAssign:
3797 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3798 // If type is const qualified or is a reference type then the
3799 // trait is false. Otherwise if __is_pod (type) is true then the
3800 // trait is true, else if type is a cv class or union type with
3801 // a trivial copy assignment ([class.copy]) then the trait is
3802 // true, else it is false.
3803 // Note: the const and reference restrictions are interesting,
3804 // given that const and reference members don't prevent a class
3805 // from having a trivial copy assignment operator (but do cause
3806 // errors if the copy assignment operator is actually used, q.v.
3807 // [class.copy]p12).
3809 if (T.isConstQualified())
3811 if (T.isPODType(Self.Context))
3813 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3814 return RD->hasTrivialCopyAssignment() &&
3815 !RD->hasNonTrivialCopyAssignment();
3817 case UTT_IsDestructible:
3818 case UTT_IsNothrowDestructible:
3819 // FIXME: Implement UTT_IsDestructible and UTT_IsNothrowDestructible.
3820 // For now, let's fall through.
3821 case UTT_HasTrivialDestructor:
3822 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
3823 // If __is_pod (type) is true or type is a reference type
3824 // then the trait is true, else if type is a cv class or union
3825 // type (or array thereof) with a trivial destructor
3826 // ([class.dtor]) then the trait is true, else it is
3828 if (T.isPODType(Self.Context) || T->isReferenceType())
3831 // Objective-C++ ARC: autorelease types don't require destruction.
3832 if (T->isObjCLifetimeType() &&
3833 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
3836 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
3837 return RD->hasTrivialDestructor();
3839 // TODO: Propagate nothrowness for implicitly declared special members.
3840 case UTT_HasNothrowAssign:
3841 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3842 // If type is const qualified or is a reference type then the
3843 // trait is false. Otherwise if __has_trivial_assign (type)
3844 // is true then the trait is true, else if type is a cv class
3845 // or union type with copy assignment operators that are known
3846 // not to throw an exception then the trait is true, else it is
3848 if (C.getBaseElementType(T).isConstQualified())
3850 if (T->isReferenceType())
3852 if (T.isPODType(Self.Context) || T->isObjCLifetimeType())
3855 if (const RecordType *RT = T->getAs<RecordType>())
3856 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
3857 &CXXRecordDecl::hasTrivialCopyAssignment,
3858 &CXXRecordDecl::hasNonTrivialCopyAssignment,
3859 &CXXMethodDecl::isCopyAssignmentOperator);
3861 case UTT_HasNothrowMoveAssign:
3862 // This trait is implemented by MSVC 2012 and needed to parse the
3863 // standard library headers. Specifically this is used as the logic
3864 // behind std::is_nothrow_move_assignable (20.9.4.3).
3865 if (T.isPODType(Self.Context))
3868 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>())
3869 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
3870 &CXXRecordDecl::hasTrivialMoveAssignment,
3871 &CXXRecordDecl::hasNonTrivialMoveAssignment,
3872 &CXXMethodDecl::isMoveAssignmentOperator);
3874 case UTT_HasNothrowCopy:
3875 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3876 // If __has_trivial_copy (type) is true then the trait is true, else
3877 // if type is a cv class or union type with copy constructors that are
3878 // known not to throw an exception then the trait is true, else it is
3880 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
3882 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
3883 if (RD->hasTrivialCopyConstructor() &&
3884 !RD->hasNonTrivialCopyConstructor())
3887 bool FoundConstructor = false;
3889 DeclContext::lookup_result R = Self.LookupConstructors(RD);
3890 for (DeclContext::lookup_iterator Con = R.begin(),
3891 ConEnd = R.end(); Con != ConEnd; ++Con) {
3892 // A template constructor is never a copy constructor.
3893 // FIXME: However, it may actually be selected at the actual overload
3894 // resolution point.
3895 if (isa<FunctionTemplateDecl>(*Con))
3897 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con);
3898 if (Constructor->isCopyConstructor(FoundTQs)) {
3899 FoundConstructor = true;
3900 const FunctionProtoType *CPT
3901 = Constructor->getType()->getAs<FunctionProtoType>();
3902 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
3905 // TODO: check whether evaluating default arguments can throw.
3906 // For now, we'll be conservative and assume that they can throw.
3907 if (!CPT->isNothrow(Self.Context) || CPT->getNumParams() > 1)
3912 return FoundConstructor;
3915 case UTT_HasNothrowConstructor:
3916 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
3917 // If __has_trivial_constructor (type) is true then the trait is
3918 // true, else if type is a cv class or union type (or array
3919 // thereof) with a default constructor that is known not to
3920 // throw an exception then the trait is true, else it is false.
3921 if (T.isPODType(C) || T->isObjCLifetimeType())
3923 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
3924 if (RD->hasTrivialDefaultConstructor() &&
3925 !RD->hasNonTrivialDefaultConstructor())
3928 bool FoundConstructor = false;
3929 DeclContext::lookup_result R = Self.LookupConstructors(RD);
3930 for (DeclContext::lookup_iterator Con = R.begin(),
3931 ConEnd = R.end(); Con != ConEnd; ++Con) {
3932 // FIXME: In C++0x, a constructor template can be a default constructor.
3933 if (isa<FunctionTemplateDecl>(*Con))
3935 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con);
3936 if (Constructor->isDefaultConstructor()) {
3937 FoundConstructor = true;
3938 const FunctionProtoType *CPT
3939 = Constructor->getType()->getAs<FunctionProtoType>();
3940 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
3943 // FIXME: check whether evaluating default arguments can throw.
3944 // For now, we'll be conservative and assume that they can throw.
3945 if (!CPT->isNothrow(Self.Context) || CPT->getNumParams() > 0)
3949 return FoundConstructor;
3952 case UTT_HasVirtualDestructor:
3953 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3954 // If type is a class type with a virtual destructor ([class.dtor])
3955 // then the trait is true, else it is false.
3956 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3957 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
3958 return Destructor->isVirtual();
3961 // These type trait expressions are modeled on the specifications for the
3962 // Embarcadero C++0x type trait functions:
3963 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
3964 case UTT_IsCompleteType:
3965 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_):
3966 // Returns True if and only if T is a complete type at the point of the
3968 return !T->isIncompleteType();
3972 /// \brief Determine whether T has a non-trivial Objective-C lifetime in
3974 static bool hasNontrivialObjCLifetime(QualType T) {
3975 switch (T.getObjCLifetime()) {
3976 case Qualifiers::OCL_ExplicitNone:
3979 case Qualifiers::OCL_Strong:
3980 case Qualifiers::OCL_Weak:
3981 case Qualifiers::OCL_Autoreleasing:
3984 case Qualifiers::OCL_None:
3985 return T->isObjCLifetimeType();
3988 llvm_unreachable("Unknown ObjC lifetime qualifier");
3991 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
3992 QualType RhsT, SourceLocation KeyLoc);
3994 static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc,
3995 ArrayRef<TypeSourceInfo *> Args,
3996 SourceLocation RParenLoc) {
3997 if (Kind <= UTT_Last)
3998 return EvaluateUnaryTypeTrait(S, Kind, KWLoc, Args[0]->getType());
4000 if (Kind <= BTT_Last)
4001 return EvaluateBinaryTypeTrait(S, Kind, Args[0]->getType(),
4002 Args[1]->getType(), RParenLoc);
4005 case clang::TT_IsConstructible:
4006 case clang::TT_IsNothrowConstructible:
4007 case clang::TT_IsTriviallyConstructible: {
4008 // C++11 [meta.unary.prop]:
4009 // is_trivially_constructible is defined as:
4011 // is_constructible<T, Args...>::value is true and the variable
4012 // definition for is_constructible, as defined below, is known to call
4013 // no operation that is not trivial.
4015 // The predicate condition for a template specialization
4016 // is_constructible<T, Args...> shall be satisfied if and only if the
4017 // following variable definition would be well-formed for some invented
4020 // T t(create<Args>()...);
4021 assert(!Args.empty());
4023 // Precondition: T and all types in the parameter pack Args shall be
4024 // complete types, (possibly cv-qualified) void, or arrays of
4026 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
4027 QualType ArgTy = Args[I]->getType();
4028 if (ArgTy->isVoidType() || ArgTy->isIncompleteArrayType())
4031 if (S.RequireCompleteType(KWLoc, ArgTy,
4032 diag::err_incomplete_type_used_in_type_trait_expr))
4036 // Make sure the first argument is a complete type.
4037 if (Args[0]->getType()->isIncompleteType())
4040 // Make sure the first argument is not an abstract type.
4041 CXXRecordDecl *RD = Args[0]->getType()->getAsCXXRecordDecl();
4042 if (RD && RD->isAbstract())
4045 SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs;
4046 SmallVector<Expr *, 2> ArgExprs;
4047 ArgExprs.reserve(Args.size() - 1);
4048 for (unsigned I = 1, N = Args.size(); I != N; ++I) {
4049 QualType T = Args[I]->getType();
4050 if (T->isObjectType() || T->isFunctionType())
4051 T = S.Context.getRValueReferenceType(T);
4052 OpaqueArgExprs.push_back(
4053 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(),
4054 T.getNonLValueExprType(S.Context),
4055 Expr::getValueKindForType(T)));
4057 for (Expr &E : OpaqueArgExprs)
4058 ArgExprs.push_back(&E);
4060 // Perform the initialization in an unevaluated context within a SFINAE
4061 // trap at translation unit scope.
4062 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated);
4063 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
4064 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl());
4065 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0]));
4066 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc,
4068 InitializationSequence Init(S, To, InitKind, ArgExprs);
4072 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs);
4073 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
4076 if (Kind == clang::TT_IsConstructible)
4079 if (Kind == clang::TT_IsNothrowConstructible)
4080 return S.canThrow(Result.get()) == CT_Cannot;
4082 if (Kind == clang::TT_IsTriviallyConstructible) {
4083 // Under Objective-C ARC, if the destination has non-trivial Objective-C
4084 // lifetime, this is a non-trivial construction.
4085 if (S.getLangOpts().ObjCAutoRefCount &&
4086 hasNontrivialObjCLifetime(Args[0]->getType().getNonReferenceType()))
4089 // The initialization succeeded; now make sure there are no non-trivial
4091 return !Result.get()->hasNonTrivialCall(S.Context);
4094 llvm_unreachable("unhandled type trait");
4097 default: llvm_unreachable("not a TT");
4103 ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4104 ArrayRef<TypeSourceInfo *> Args,
4105 SourceLocation RParenLoc) {
4106 QualType ResultType = Context.getLogicalOperationType();
4108 if (Kind <= UTT_Last && !CheckUnaryTypeTraitTypeCompleteness(
4109 *this, Kind, KWLoc, Args[0]->getType()))
4112 bool Dependent = false;
4113 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
4114 if (Args[I]->getType()->isDependentType()) {
4120 bool Result = false;
4122 Result = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc);
4124 return TypeTraitExpr::Create(Context, ResultType, KWLoc, Kind, Args,
4128 ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
4129 ArrayRef<ParsedType> Args,
4130 SourceLocation RParenLoc) {
4131 SmallVector<TypeSourceInfo *, 4> ConvertedArgs;
4132 ConvertedArgs.reserve(Args.size());
4134 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
4135 TypeSourceInfo *TInfo;
4136 QualType T = GetTypeFromParser(Args[I], &TInfo);
4138 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc);
4140 ConvertedArgs.push_back(TInfo);
4143 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc);
4146 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
4147 QualType RhsT, SourceLocation KeyLoc) {
4148 assert(!LhsT->isDependentType() && !RhsT->isDependentType() &&
4149 "Cannot evaluate traits of dependent types");
4152 case BTT_IsBaseOf: {
4153 // C++0x [meta.rel]p2
4154 // Base is a base class of Derived without regard to cv-qualifiers or
4155 // Base and Derived are not unions and name the same class type without
4156 // regard to cv-qualifiers.
4158 const RecordType *lhsRecord = LhsT->getAs<RecordType>();
4159 if (!lhsRecord) return false;
4161 const RecordType *rhsRecord = RhsT->getAs<RecordType>();
4162 if (!rhsRecord) return false;
4164 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT)
4165 == (lhsRecord == rhsRecord));
4167 if (lhsRecord == rhsRecord)
4168 return !lhsRecord->getDecl()->isUnion();
4170 // C++0x [meta.rel]p2:
4171 // If Base and Derived are class types and are different types
4172 // (ignoring possible cv-qualifiers) then Derived shall be a
4174 if (Self.RequireCompleteType(KeyLoc, RhsT,
4175 diag::err_incomplete_type_used_in_type_trait_expr))
4178 return cast<CXXRecordDecl>(rhsRecord->getDecl())
4179 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl()));
4182 return Self.Context.hasSameType(LhsT, RhsT);
4183 case BTT_TypeCompatible:
4184 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(),
4185 RhsT.getUnqualifiedType());
4186 case BTT_IsConvertible:
4187 case BTT_IsConvertibleTo: {
4188 // C++0x [meta.rel]p4:
4189 // Given the following function prototype:
4191 // template <class T>
4192 // typename add_rvalue_reference<T>::type create();
4194 // the predicate condition for a template specialization
4195 // is_convertible<From, To> shall be satisfied if and only if
4196 // the return expression in the following code would be
4197 // well-formed, including any implicit conversions to the return
4198 // type of the function:
4201 // return create<From>();
4204 // Access checking is performed as if in a context unrelated to To and
4205 // From. Only the validity of the immediate context of the expression
4206 // of the return-statement (including conversions to the return type)
4209 // We model the initialization as a copy-initialization of a temporary
4210 // of the appropriate type, which for this expression is identical to the
4211 // return statement (since NRVO doesn't apply).
4213 // Functions aren't allowed to return function or array types.
4214 if (RhsT->isFunctionType() || RhsT->isArrayType())
4217 // A return statement in a void function must have void type.
4218 if (RhsT->isVoidType())
4219 return LhsT->isVoidType();
4221 // A function definition requires a complete, non-abstract return type.
4222 if (Self.RequireCompleteType(KeyLoc, RhsT, 0) ||
4223 Self.RequireNonAbstractType(KeyLoc, RhsT, 0))
4226 // Compute the result of add_rvalue_reference.
4227 if (LhsT->isObjectType() || LhsT->isFunctionType())
4228 LhsT = Self.Context.getRValueReferenceType(LhsT);
4230 // Build a fake source and destination for initialization.
4231 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT));
4232 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
4233 Expr::getValueKindForType(LhsT));
4234 Expr *FromPtr = &From;
4235 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc,
4238 // Perform the initialization in an unevaluated context within a SFINAE
4239 // trap at translation unit scope.
4240 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated);
4241 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
4242 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
4243 InitializationSequence Init(Self, To, Kind, FromPtr);
4247 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr);
4248 return !Result.isInvalid() && !SFINAE.hasErrorOccurred();
4251 case BTT_IsNothrowAssignable:
4252 case BTT_IsTriviallyAssignable: {
4253 // C++11 [meta.unary.prop]p3:
4254 // is_trivially_assignable is defined as:
4255 // is_assignable<T, U>::value is true and the assignment, as defined by
4256 // is_assignable, is known to call no operation that is not trivial
4258 // is_assignable is defined as:
4259 // The expression declval<T>() = declval<U>() is well-formed when
4260 // treated as an unevaluated operand (Clause 5).
4262 // For both, T and U shall be complete types, (possibly cv-qualified)
4263 // void, or arrays of unknown bound.
4264 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() &&
4265 Self.RequireCompleteType(KeyLoc, LhsT,
4266 diag::err_incomplete_type_used_in_type_trait_expr))
4268 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() &&
4269 Self.RequireCompleteType(KeyLoc, RhsT,
4270 diag::err_incomplete_type_used_in_type_trait_expr))
4273 // cv void is never assignable.
4274 if (LhsT->isVoidType() || RhsT->isVoidType())
4277 // Build expressions that emulate the effect of declval<T>() and
4279 if (LhsT->isObjectType() || LhsT->isFunctionType())
4280 LhsT = Self.Context.getRValueReferenceType(LhsT);
4281 if (RhsT->isObjectType() || RhsT->isFunctionType())
4282 RhsT = Self.Context.getRValueReferenceType(RhsT);
4283 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
4284 Expr::getValueKindForType(LhsT));
4285 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context),
4286 Expr::getValueKindForType(RhsT));
4288 // Attempt the assignment in an unevaluated context within a SFINAE
4289 // trap at translation unit scope.
4290 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated);
4291 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
4292 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
4293 ExprResult Result = Self.BuildBinOp(/*S=*/nullptr, KeyLoc, BO_Assign, &Lhs,
4295 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
4298 if (BTT == BTT_IsNothrowAssignable)
4299 return Self.canThrow(Result.get()) == CT_Cannot;
4301 if (BTT == BTT_IsTriviallyAssignable) {
4302 // Under Objective-C ARC, if the destination has non-trivial Objective-C
4303 // lifetime, this is a non-trivial assignment.
4304 if (Self.getLangOpts().ObjCAutoRefCount &&
4305 hasNontrivialObjCLifetime(LhsT.getNonReferenceType()))
4308 return !Result.get()->hasNonTrivialCall(Self.Context);
4311 llvm_unreachable("unhandled type trait");
4314 default: llvm_unreachable("not a BTT");
4316 llvm_unreachable("Unknown type trait or not implemented");
4319 ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT,
4320 SourceLocation KWLoc,
4323 SourceLocation RParen) {
4324 TypeSourceInfo *TSInfo;
4325 QualType T = GetTypeFromParser(Ty, &TSInfo);
4327 TSInfo = Context.getTrivialTypeSourceInfo(T);
4329 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen);
4332 static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT,
4333 QualType T, Expr *DimExpr,
4334 SourceLocation KeyLoc) {
4335 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
4339 if (T->isArrayType()) {
4341 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
4343 T = AT->getElementType();
4349 case ATT_ArrayExtent: {
4352 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value,
4353 diag::err_dimension_expr_not_constant_integer,
4356 if (Value.isSigned() && Value.isNegative()) {
4357 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer)
4358 << DimExpr->getSourceRange();
4361 Dim = Value.getLimitedValue();
4363 if (T->isArrayType()) {
4365 bool Matched = false;
4366 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
4372 T = AT->getElementType();
4375 if (Matched && T->isArrayType()) {
4376 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T))
4377 return CAT->getSize().getLimitedValue();
4383 llvm_unreachable("Unknown type trait or not implemented");
4386 ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT,
4387 SourceLocation KWLoc,
4388 TypeSourceInfo *TSInfo,
4390 SourceLocation RParen) {
4391 QualType T = TSInfo->getType();
4393 // FIXME: This should likely be tracked as an APInt to remove any host
4394 // assumptions about the width of size_t on the target.
4396 if (!T->isDependentType())
4397 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc);
4399 // While the specification for these traits from the Embarcadero C++
4400 // compiler's documentation says the return type is 'unsigned int', Clang
4401 // returns 'size_t'. On Windows, the primary platform for the Embarcadero
4402 // compiler, there is no difference. On several other platforms this is an
4403 // important distinction.
4404 return new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, DimExpr,
4405 RParen, Context.getSizeType());
4408 ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET,
4409 SourceLocation KWLoc,
4411 SourceLocation RParen) {
4412 // If error parsing the expression, ignore.
4416 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen);
4421 static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) {
4423 case ET_IsLValueExpr: return E->isLValue();
4424 case ET_IsRValueExpr: return E->isRValue();
4426 llvm_unreachable("Expression trait not covered by switch");
4429 ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET,
4430 SourceLocation KWLoc,
4432 SourceLocation RParen) {
4433 if (Queried->isTypeDependent()) {
4434 // Delay type-checking for type-dependent expressions.
4435 } else if (Queried->getType()->isPlaceholderType()) {
4436 ExprResult PE = CheckPlaceholderExpr(Queried);
4437 if (PE.isInvalid()) return ExprError();
4438 return BuildExpressionTrait(ET, KWLoc, PE.get(), RParen);
4441 bool Value = EvaluateExpressionTrait(ET, Queried);
4443 return new (Context)
4444 ExpressionTraitExpr(KWLoc, ET, Queried, Value, RParen, Context.BoolTy);
4447 QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS,
4451 assert(!LHS.get()->getType()->isPlaceholderType() &&
4452 !RHS.get()->getType()->isPlaceholderType() &&
4453 "placeholders should have been weeded out by now");
4455 // The LHS undergoes lvalue conversions if this is ->*.
4457 LHS = DefaultLvalueConversion(LHS.get());
4458 if (LHS.isInvalid()) return QualType();
4461 // The RHS always undergoes lvalue conversions.
4462 RHS = DefaultLvalueConversion(RHS.get());
4463 if (RHS.isInvalid()) return QualType();
4465 const char *OpSpelling = isIndirect ? "->*" : ".*";
4467 // The binary operator .* [p3: ->*] binds its second operand, which shall
4468 // be of type "pointer to member of T" (where T is a completely-defined
4469 // class type) [...]
4470 QualType RHSType = RHS.get()->getType();
4471 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>();
4473 Diag(Loc, diag::err_bad_memptr_rhs)
4474 << OpSpelling << RHSType << RHS.get()->getSourceRange();
4478 QualType Class(MemPtr->getClass(), 0);
4480 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the
4481 // member pointer points must be completely-defined. However, there is no
4482 // reason for this semantic distinction, and the rule is not enforced by
4483 // other compilers. Therefore, we do not check this property, as it is
4484 // likely to be considered a defect.
4487 // [...] to its first operand, which shall be of class T or of a class of
4488 // which T is an unambiguous and accessible base class. [p3: a pointer to
4490 QualType LHSType = LHS.get()->getType();
4492 if (const PointerType *Ptr = LHSType->getAs<PointerType>())
4493 LHSType = Ptr->getPointeeType();
4495 Diag(Loc, diag::err_bad_memptr_lhs)
4496 << OpSpelling << 1 << LHSType
4497 << FixItHint::CreateReplacement(SourceRange(Loc), ".*");
4502 if (!Context.hasSameUnqualifiedType(Class, LHSType)) {
4503 // If we want to check the hierarchy, we need a complete type.
4504 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs,
4505 OpSpelling, (int)isIndirect)) {
4509 if (!IsDerivedFrom(LHSType, Class)) {
4510 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling
4511 << (int)isIndirect << LHS.get()->getType();
4515 CXXCastPath BasePath;
4516 if (CheckDerivedToBaseConversion(LHSType, Class, Loc,
4517 SourceRange(LHS.get()->getLocStart(),
4518 RHS.get()->getLocEnd()),
4522 // Cast LHS to type of use.
4523 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class;
4524 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind();
4525 LHS = ImpCastExprToType(LHS.get(), UseType, CK_DerivedToBase, VK,
4529 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) {
4530 // Diagnose use of pointer-to-member type which when used as
4531 // the functional cast in a pointer-to-member expression.
4532 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect;
4537 // The result is an object or a function of the type specified by the
4539 // The cv qualifiers are the union of those in the pointer and the left side,
4540 // in accordance with 5.5p5 and 5.2.5.
4541 QualType Result = MemPtr->getPointeeType();
4542 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers());
4544 // C++0x [expr.mptr.oper]p6:
4545 // In a .* expression whose object expression is an rvalue, the program is
4546 // ill-formed if the second operand is a pointer to member function with
4547 // ref-qualifier &. In a ->* expression or in a .* expression whose object
4548 // expression is an lvalue, the program is ill-formed if the second operand
4549 // is a pointer to member function with ref-qualifier &&.
4550 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) {
4551 switch (Proto->getRefQualifier()) {
4557 if (!isIndirect && !LHS.get()->Classify(Context).isLValue())
4558 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
4559 << RHSType << 1 << LHS.get()->getSourceRange();
4563 if (isIndirect || !LHS.get()->Classify(Context).isRValue())
4564 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
4565 << RHSType << 0 << LHS.get()->getSourceRange();
4570 // C++ [expr.mptr.oper]p6:
4571 // The result of a .* expression whose second operand is a pointer
4572 // to a data member is of the same value category as its
4573 // first operand. The result of a .* expression whose second
4574 // operand is a pointer to a member function is a prvalue. The
4575 // result of an ->* expression is an lvalue if its second operand
4576 // is a pointer to data member and a prvalue otherwise.
4577 if (Result->isFunctionType()) {
4579 return Context.BoundMemberTy;
4580 } else if (isIndirect) {
4583 VK = LHS.get()->getValueKind();
4589 /// \brief Try to convert a type to another according to C++0x 5.16p3.
4591 /// This is part of the parameter validation for the ? operator. If either
4592 /// value operand is a class type, the two operands are attempted to be
4593 /// converted to each other. This function does the conversion in one direction.
4594 /// It returns true if the program is ill-formed and has already been diagnosed
4596 static bool TryClassUnification(Sema &Self, Expr *From, Expr *To,
4597 SourceLocation QuestionLoc,
4598 bool &HaveConversion,
4600 HaveConversion = false;
4601 ToType = To->getType();
4603 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(),
4606 // The process for determining whether an operand expression E1 of type T1
4607 // can be converted to match an operand expression E2 of type T2 is defined
4609 // -- If E2 is an lvalue:
4610 bool ToIsLvalue = To->isLValue();
4612 // E1 can be converted to match E2 if E1 can be implicitly converted to
4613 // type "lvalue reference to T2", subject to the constraint that in the
4614 // conversion the reference must bind directly to E1.
4615 QualType T = Self.Context.getLValueReferenceType(ToType);
4616 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
4618 InitializationSequence InitSeq(Self, Entity, Kind, From);
4619 if (InitSeq.isDirectReferenceBinding()) {
4621 HaveConversion = true;
4625 if (InitSeq.isAmbiguous())
4626 return InitSeq.Diagnose(Self, Entity, Kind, From);
4629 // -- If E2 is an rvalue, or if the conversion above cannot be done:
4630 // -- if E1 and E2 have class type, and the underlying class types are
4631 // the same or one is a base class of the other:
4632 QualType FTy = From->getType();
4633 QualType TTy = To->getType();
4634 const RecordType *FRec = FTy->getAs<RecordType>();
4635 const RecordType *TRec = TTy->getAs<RecordType>();
4636 bool FDerivedFromT = FRec && TRec && FRec != TRec &&
4637 Self.IsDerivedFrom(FTy, TTy);
4639 (FRec == TRec || FDerivedFromT || Self.IsDerivedFrom(TTy, FTy))) {
4640 // E1 can be converted to match E2 if the class of T2 is the
4641 // same type as, or a base class of, the class of T1, and
4643 if (FRec == TRec || FDerivedFromT) {
4644 if (TTy.isAtLeastAsQualifiedAs(FTy)) {
4645 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
4646 InitializationSequence InitSeq(Self, Entity, Kind, From);
4648 HaveConversion = true;
4652 if (InitSeq.isAmbiguous())
4653 return InitSeq.Diagnose(Self, Entity, Kind, From);
4660 // -- Otherwise: E1 can be converted to match E2 if E1 can be
4661 // implicitly converted to the type that expression E2 would have
4662 // if E2 were converted to an rvalue (or the type it has, if E2 is
4665 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not
4666 // to the array-to-pointer or function-to-pointer conversions.
4667 if (!TTy->getAs<TagType>())
4668 TTy = TTy.getUnqualifiedType();
4670 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
4671 InitializationSequence InitSeq(Self, Entity, Kind, From);
4672 HaveConversion = !InitSeq.Failed();
4674 if (InitSeq.isAmbiguous())
4675 return InitSeq.Diagnose(Self, Entity, Kind, From);
4680 /// \brief Try to find a common type for two according to C++0x 5.16p5.
4682 /// This is part of the parameter validation for the ? operator. If either
4683 /// value operand is a class type, overload resolution is used to find a
4684 /// conversion to a common type.
4685 static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS,
4686 SourceLocation QuestionLoc) {
4687 Expr *Args[2] = { LHS.get(), RHS.get() };
4688 OverloadCandidateSet CandidateSet(QuestionLoc,
4689 OverloadCandidateSet::CSK_Operator);
4690 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args,
4693 OverloadCandidateSet::iterator Best;
4694 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) {
4696 // We found a match. Perform the conversions on the arguments and move on.
4698 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0],
4699 Best->Conversions[0], Sema::AA_Converting);
4700 if (LHSRes.isInvalid())
4705 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1],
4706 Best->Conversions[1], Sema::AA_Converting);
4707 if (RHSRes.isInvalid())
4711 Self.MarkFunctionReferenced(QuestionLoc, Best->Function);
4715 case OR_No_Viable_Function:
4717 // Emit a better diagnostic if one of the expressions is a null pointer
4718 // constant and the other is a pointer type. In this case, the user most
4719 // likely forgot to take the address of the other expression.
4720 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
4723 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
4724 << LHS.get()->getType() << RHS.get()->getType()
4725 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4729 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl)
4730 << LHS.get()->getType() << RHS.get()->getType()
4731 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4732 // FIXME: Print the possible common types by printing the return types of
4733 // the viable candidates.
4737 llvm_unreachable("Conditional operator has only built-in overloads");
4742 /// \brief Perform an "extended" implicit conversion as returned by
4743 /// TryClassUnification.
4744 static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) {
4745 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
4746 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(),
4748 Expr *Arg = E.get();
4749 InitializationSequence InitSeq(Self, Entity, Kind, Arg);
4750 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, Arg);
4751 if (Result.isInvalid())
4758 /// \brief Check the operands of ?: under C++ semantics.
4760 /// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y
4761 /// extension. In this case, LHS == Cond. (But they're not aliases.)
4762 QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
4763 ExprResult &RHS, ExprValueKind &VK,
4765 SourceLocation QuestionLoc) {
4766 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++
4767 // interface pointers.
4769 // C++11 [expr.cond]p1
4770 // The first expression is contextually converted to bool.
4771 if (!Cond.get()->isTypeDependent()) {
4772 ExprResult CondRes = CheckCXXBooleanCondition(Cond.get());
4773 if (CondRes.isInvalid())
4782 // Either of the arguments dependent?
4783 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent())
4784 return Context.DependentTy;
4786 // C++11 [expr.cond]p2
4787 // If either the second or the third operand has type (cv) void, ...
4788 QualType LTy = LHS.get()->getType();
4789 QualType RTy = RHS.get()->getType();
4790 bool LVoid = LTy->isVoidType();
4791 bool RVoid = RTy->isVoidType();
4792 if (LVoid || RVoid) {
4793 // ... one of the following shall hold:
4794 // -- The second or the third operand (but not both) is a (possibly
4795 // parenthesized) throw-expression; the result is of the type
4796 // and value category of the other.
4797 bool LThrow = isa<CXXThrowExpr>(LHS.get()->IgnoreParenImpCasts());
4798 bool RThrow = isa<CXXThrowExpr>(RHS.get()->IgnoreParenImpCasts());
4799 if (LThrow != RThrow) {
4800 Expr *NonThrow = LThrow ? RHS.get() : LHS.get();
4801 VK = NonThrow->getValueKind();
4802 // DR (no number yet): the result is a bit-field if the
4803 // non-throw-expression operand is a bit-field.
4804 OK = NonThrow->getObjectKind();
4805 return NonThrow->getType();
4808 // -- Both the second and third operands have type void; the result is of
4809 // type void and is a prvalue.
4811 return Context.VoidTy;
4813 // Neither holds, error.
4814 Diag(QuestionLoc, diag::err_conditional_void_nonvoid)
4815 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1)
4816 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4822 // C++11 [expr.cond]p3
4823 // Otherwise, if the second and third operand have different types, and
4824 // either has (cv) class type [...] an attempt is made to convert each of
4825 // those operands to the type of the other.
4826 if (!Context.hasSameType(LTy, RTy) &&
4827 (LTy->isRecordType() || RTy->isRecordType())) {
4828 // These return true if a single direction is already ambiguous.
4829 QualType L2RType, R2LType;
4830 bool HaveL2R, HaveR2L;
4831 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType))
4833 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType))
4836 // If both can be converted, [...] the program is ill-formed.
4837 if (HaveL2R && HaveR2L) {
4838 Diag(QuestionLoc, diag::err_conditional_ambiguous)
4839 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4843 // If exactly one conversion is possible, that conversion is applied to
4844 // the chosen operand and the converted operands are used in place of the
4845 // original operands for the remainder of this section.
4847 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid())
4849 LTy = LHS.get()->getType();
4850 } else if (HaveR2L) {
4851 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid())
4853 RTy = RHS.get()->getType();
4857 // C++11 [expr.cond]p3
4858 // if both are glvalues of the same value category and the same type except
4859 // for cv-qualification, an attempt is made to convert each of those
4860 // operands to the type of the other.
4861 ExprValueKind LVK = LHS.get()->getValueKind();
4862 ExprValueKind RVK = RHS.get()->getValueKind();
4863 if (!Context.hasSameType(LTy, RTy) &&
4864 Context.hasSameUnqualifiedType(LTy, RTy) &&
4865 LVK == RVK && LVK != VK_RValue) {
4866 // Since the unqualified types are reference-related and we require the
4867 // result to be as if a reference bound directly, the only conversion
4868 // we can perform is to add cv-qualifiers.
4869 Qualifiers LCVR = Qualifiers::fromCVRMask(LTy.getCVRQualifiers());
4870 Qualifiers RCVR = Qualifiers::fromCVRMask(RTy.getCVRQualifiers());
4871 if (RCVR.isStrictSupersetOf(LCVR)) {
4872 LHS = ImpCastExprToType(LHS.get(), RTy, CK_NoOp, LVK);
4873 LTy = LHS.get()->getType();
4875 else if (LCVR.isStrictSupersetOf(RCVR)) {
4876 RHS = ImpCastExprToType(RHS.get(), LTy, CK_NoOp, RVK);
4877 RTy = RHS.get()->getType();
4881 // C++11 [expr.cond]p4
4882 // If the second and third operands are glvalues of the same value
4883 // category and have the same type, the result is of that type and
4884 // value category and it is a bit-field if the second or the third
4885 // operand is a bit-field, or if both are bit-fields.
4886 // We only extend this to bitfields, not to the crazy other kinds of
4888 bool Same = Context.hasSameType(LTy, RTy);
4889 if (Same && LVK == RVK && LVK != VK_RValue &&
4890 LHS.get()->isOrdinaryOrBitFieldObject() &&
4891 RHS.get()->isOrdinaryOrBitFieldObject()) {
4892 VK = LHS.get()->getValueKind();
4893 if (LHS.get()->getObjectKind() == OK_BitField ||
4894 RHS.get()->getObjectKind() == OK_BitField)
4899 // C++11 [expr.cond]p5
4900 // Otherwise, the result is a prvalue. If the second and third operands
4901 // do not have the same type, and either has (cv) class type, ...
4902 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) {
4903 // ... overload resolution is used to determine the conversions (if any)
4904 // to be applied to the operands. If the overload resolution fails, the
4905 // program is ill-formed.
4906 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc))
4910 // C++11 [expr.cond]p6
4911 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard
4912 // conversions are performed on the second and third operands.
4913 LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
4914 RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
4915 if (LHS.isInvalid() || RHS.isInvalid())
4917 LTy = LHS.get()->getType();
4918 RTy = RHS.get()->getType();
4920 // After those conversions, one of the following shall hold:
4921 // -- The second and third operands have the same type; the result
4922 // is of that type. If the operands have class type, the result
4923 // is a prvalue temporary of the result type, which is
4924 // copy-initialized from either the second operand or the third
4925 // operand depending on the value of the first operand.
4926 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) {
4927 if (LTy->isRecordType()) {
4928 // The operands have class type. Make a temporary copy.
4929 if (RequireNonAbstractType(QuestionLoc, LTy,
4930 diag::err_allocation_of_abstract_type))
4932 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy);
4934 ExprResult LHSCopy = PerformCopyInitialization(Entity,
4937 if (LHSCopy.isInvalid())
4940 ExprResult RHSCopy = PerformCopyInitialization(Entity,
4943 if (RHSCopy.isInvalid())
4953 // Extension: conditional operator involving vector types.
4954 if (LTy->isVectorType() || RTy->isVectorType())
4955 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false,
4956 /*AllowBothBool*/true,
4957 /*AllowBoolConversions*/false);
4959 // -- The second and third operands have arithmetic or enumeration type;
4960 // the usual arithmetic conversions are performed to bring them to a
4961 // common type, and the result is of that type.
4962 if (LTy->isArithmeticType() && RTy->isArithmeticType()) {
4963 QualType ResTy = UsualArithmeticConversions(LHS, RHS);
4964 if (LHS.isInvalid() || RHS.isInvalid())
4967 LHS = ImpCastExprToType(LHS.get(), ResTy, PrepareScalarCast(LHS, ResTy));
4968 RHS = ImpCastExprToType(RHS.get(), ResTy, PrepareScalarCast(RHS, ResTy));
4973 // -- The second and third operands have pointer type, or one has pointer
4974 // type and the other is a null pointer constant, or both are null
4975 // pointer constants, at least one of which is non-integral; pointer
4976 // conversions and qualification conversions are performed to bring them
4977 // to their composite pointer type. The result is of the composite
4979 // -- The second and third operands have pointer to member type, or one has
4980 // pointer to member type and the other is a null pointer constant;
4981 // pointer to member conversions and qualification conversions are
4982 // performed to bring them to a common type, whose cv-qualification
4983 // shall match the cv-qualification of either the second or the third
4984 // operand. The result is of the common type.
4985 bool NonStandardCompositeType = false;
4986 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS,
4987 isSFINAEContext() ? nullptr
4988 : &NonStandardCompositeType);
4989 if (!Composite.isNull()) {
4990 if (NonStandardCompositeType)
4992 diag::ext_typecheck_cond_incompatible_operands_nonstandard)
4993 << LTy << RTy << Composite
4994 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4999 // Similarly, attempt to find composite type of two objective-c pointers.
5000 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc);
5001 if (!Composite.isNull())
5004 // Check if we are using a null with a non-pointer type.
5005 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
5008 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
5009 << LHS.get()->getType() << RHS.get()->getType()
5010 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
5014 /// \brief Find a merged pointer type and convert the two expressions to it.
5016 /// This finds the composite pointer type (or member pointer type) for @p E1
5017 /// and @p E2 according to C++11 5.9p2. It converts both expressions to this
5018 /// type and returns it.
5019 /// It does not emit diagnostics.
5021 /// \param Loc The location of the operator requiring these two expressions to
5022 /// be converted to the composite pointer type.
5024 /// If \p NonStandardCompositeType is non-NULL, then we are permitted to find
5025 /// a non-standard (but still sane) composite type to which both expressions
5026 /// can be converted. When such a type is chosen, \c *NonStandardCompositeType
5027 /// will be set true.
5028 QualType Sema::FindCompositePointerType(SourceLocation Loc,
5029 Expr *&E1, Expr *&E2,
5030 bool *NonStandardCompositeType) {
5031 if (NonStandardCompositeType)
5032 *NonStandardCompositeType = false;
5034 assert(getLangOpts().CPlusPlus && "This function assumes C++");
5035 QualType T1 = E1->getType(), T2 = E2->getType();
5038 // Pointer conversions and qualification conversions are performed on
5039 // pointer operands to bring them to their composite pointer type. If
5040 // one operand is a null pointer constant, the composite pointer type is
5041 // std::nullptr_t if the other operand is also a null pointer constant or,
5042 // if the other operand is a pointer, the type of the other operand.
5043 if (!T1->isAnyPointerType() && !T1->isMemberPointerType() &&
5044 !T2->isAnyPointerType() && !T2->isMemberPointerType()) {
5045 if (T1->isNullPtrType() &&
5046 E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5047 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).get();
5050 if (T2->isNullPtrType() &&
5051 E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5052 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).get();
5058 if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5059 if (T2->isMemberPointerType())
5060 E1 = ImpCastExprToType(E1, T2, CK_NullToMemberPointer).get();
5062 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).get();
5065 if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
5066 if (T1->isMemberPointerType())
5067 E2 = ImpCastExprToType(E2, T1, CK_NullToMemberPointer).get();
5069 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).get();
5073 // Now both have to be pointers or member pointers.
5074 if ((!T1->isPointerType() && !T1->isMemberPointerType()) ||
5075 (!T2->isPointerType() && !T2->isMemberPointerType()))
5078 // Otherwise, of one of the operands has type "pointer to cv1 void," then
5079 // the other has type "pointer to cv2 T" and the composite pointer type is
5080 // "pointer to cv12 void," where cv12 is the union of cv1 and cv2.
5081 // Otherwise, the composite pointer type is a pointer type similar to the
5082 // type of one of the operands, with a cv-qualification signature that is
5083 // the union of the cv-qualification signatures of the operand types.
5084 // In practice, the first part here is redundant; it's subsumed by the second.
5085 // What we do here is, we build the two possible composite types, and try the
5086 // conversions in both directions. If only one works, or if the two composite
5087 // types are the same, we have succeeded.
5088 // FIXME: extended qualifiers?
5089 typedef SmallVector<unsigned, 4> QualifierVector;
5090 QualifierVector QualifierUnion;
5091 typedef SmallVector<std::pair<const Type *, const Type *>, 4>
5092 ContainingClassVector;
5093 ContainingClassVector MemberOfClass;
5094 QualType Composite1 = Context.getCanonicalType(T1),
5095 Composite2 = Context.getCanonicalType(T2);
5096 unsigned NeedConstBefore = 0;
5098 const PointerType *Ptr1, *Ptr2;
5099 if ((Ptr1 = Composite1->getAs<PointerType>()) &&
5100 (Ptr2 = Composite2->getAs<PointerType>())) {
5101 Composite1 = Ptr1->getPointeeType();
5102 Composite2 = Ptr2->getPointeeType();
5104 // If we're allowed to create a non-standard composite type, keep track
5105 // of where we need to fill in additional 'const' qualifiers.
5106 if (NonStandardCompositeType &&
5107 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
5108 NeedConstBefore = QualifierUnion.size();
5110 QualifierUnion.push_back(
5111 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
5112 MemberOfClass.push_back(std::make_pair(nullptr, nullptr));
5116 const MemberPointerType *MemPtr1, *MemPtr2;
5117 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) &&
5118 (MemPtr2 = Composite2->getAs<MemberPointerType>())) {
5119 Composite1 = MemPtr1->getPointeeType();
5120 Composite2 = MemPtr2->getPointeeType();
5122 // If we're allowed to create a non-standard composite type, keep track
5123 // of where we need to fill in additional 'const' qualifiers.
5124 if (NonStandardCompositeType &&
5125 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
5126 NeedConstBefore = QualifierUnion.size();
5128 QualifierUnion.push_back(
5129 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
5130 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(),
5131 MemPtr2->getClass()));
5135 // FIXME: block pointer types?
5137 // Cannot unwrap any more types.
5141 if (NeedConstBefore && NonStandardCompositeType) {
5142 // Extension: Add 'const' to qualifiers that come before the first qualifier
5143 // mismatch, so that our (non-standard!) composite type meets the
5144 // requirements of C++ [conv.qual]p4 bullet 3.
5145 for (unsigned I = 0; I != NeedConstBefore; ++I) {
5146 if ((QualifierUnion[I] & Qualifiers::Const) == 0) {
5147 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const;
5148 *NonStandardCompositeType = true;
5153 // Rewrap the composites as pointers or member pointers with the union CVRs.
5154 ContainingClassVector::reverse_iterator MOC
5155 = MemberOfClass.rbegin();
5156 for (QualifierVector::reverse_iterator
5157 I = QualifierUnion.rbegin(),
5158 E = QualifierUnion.rend();
5159 I != E; (void)++I, ++MOC) {
5160 Qualifiers Quals = Qualifiers::fromCVRMask(*I);
5161 if (MOC->first && MOC->second) {
5162 // Rebuild member pointer type
5163 Composite1 = Context.getMemberPointerType(
5164 Context.getQualifiedType(Composite1, Quals),
5166 Composite2 = Context.getMemberPointerType(
5167 Context.getQualifiedType(Composite2, Quals),
5170 // Rebuild pointer type
5172 = Context.getPointerType(Context.getQualifiedType(Composite1, Quals));
5174 = Context.getPointerType(Context.getQualifiedType(Composite2, Quals));
5178 // Try to convert to the first composite pointer type.
5179 InitializedEntity Entity1
5180 = InitializedEntity::InitializeTemporary(Composite1);
5181 InitializationKind Kind
5182 = InitializationKind::CreateCopy(Loc, SourceLocation());
5183 InitializationSequence E1ToC1(*this, Entity1, Kind, E1);
5184 InitializationSequence E2ToC1(*this, Entity1, Kind, E2);
5186 if (E1ToC1 && E2ToC1) {
5187 // Conversion to Composite1 is viable.
5188 if (!Context.hasSameType(Composite1, Composite2)) {
5189 // Composite2 is a different type from Composite1. Check whether
5190 // Composite2 is also viable.
5191 InitializedEntity Entity2
5192 = InitializedEntity::InitializeTemporary(Composite2);
5193 InitializationSequence E1ToC2(*this, Entity2, Kind, E1);
5194 InitializationSequence E2ToC2(*this, Entity2, Kind, E2);
5195 if (E1ToC2 && E2ToC2) {
5196 // Both Composite1 and Composite2 are viable and are different;
5197 // this is an ambiguity.
5202 // Convert E1 to Composite1
5204 = E1ToC1.Perform(*this, Entity1, Kind, E1);
5205 if (E1Result.isInvalid())
5207 E1 = E1Result.getAs<Expr>();
5209 // Convert E2 to Composite1
5211 = E2ToC1.Perform(*this, Entity1, Kind, E2);
5212 if (E2Result.isInvalid())
5214 E2 = E2Result.getAs<Expr>();
5219 // Check whether Composite2 is viable.
5220 InitializedEntity Entity2
5221 = InitializedEntity::InitializeTemporary(Composite2);
5222 InitializationSequence E1ToC2(*this, Entity2, Kind, E1);
5223 InitializationSequence E2ToC2(*this, Entity2, Kind, E2);
5224 if (!E1ToC2 || !E2ToC2)
5227 // Convert E1 to Composite2
5229 = E1ToC2.Perform(*this, Entity2, Kind, E1);
5230 if (E1Result.isInvalid())
5232 E1 = E1Result.getAs<Expr>();
5234 // Convert E2 to Composite2
5236 = E2ToC2.Perform(*this, Entity2, Kind, E2);
5237 if (E2Result.isInvalid())
5239 E2 = E2Result.getAs<Expr>();
5244 ExprResult Sema::MaybeBindToTemporary(Expr *E) {
5248 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?");
5250 // If the result is a glvalue, we shouldn't bind it.
5254 // In ARC, calls that return a retainable type can return retained,
5255 // in which case we have to insert a consuming cast.
5256 if (getLangOpts().ObjCAutoRefCount &&
5257 E->getType()->isObjCRetainableType()) {
5259 bool ReturnsRetained;
5261 // For actual calls, we compute this by examining the type of the
5263 if (CallExpr *Call = dyn_cast<CallExpr>(E)) {
5264 Expr *Callee = Call->getCallee()->IgnoreParens();
5265 QualType T = Callee->getType();
5267 if (T == Context.BoundMemberTy) {
5268 // Handle pointer-to-members.
5269 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee))
5270 T = BinOp->getRHS()->getType();
5271 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee))
5272 T = Mem->getMemberDecl()->getType();
5275 if (const PointerType *Ptr = T->getAs<PointerType>())
5276 T = Ptr->getPointeeType();
5277 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>())
5278 T = Ptr->getPointeeType();
5279 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>())
5280 T = MemPtr->getPointeeType();
5282 const FunctionType *FTy = T->getAs<FunctionType>();
5283 assert(FTy && "call to value not of function type?");
5284 ReturnsRetained = FTy->getExtInfo().getProducesResult();
5286 // ActOnStmtExpr arranges things so that StmtExprs of retainable
5287 // type always produce a +1 object.
5288 } else if (isa<StmtExpr>(E)) {
5289 ReturnsRetained = true;
5291 // We hit this case with the lambda conversion-to-block optimization;
5292 // we don't want any extra casts here.
5293 } else if (isa<CastExpr>(E) &&
5294 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) {
5297 // For message sends and property references, we try to find an
5298 // actual method. FIXME: we should infer retention by selector in
5299 // cases where we don't have an actual method.
5301 ObjCMethodDecl *D = nullptr;
5302 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) {
5303 D = Send->getMethodDecl();
5304 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) {
5305 D = BoxedExpr->getBoxingMethod();
5306 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) {
5307 D = ArrayLit->getArrayWithObjectsMethod();
5308 } else if (ObjCDictionaryLiteral *DictLit
5309 = dyn_cast<ObjCDictionaryLiteral>(E)) {
5310 D = DictLit->getDictWithObjectsMethod();
5313 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>());
5315 // Don't do reclaims on performSelector calls; despite their
5316 // return type, the invoked method doesn't necessarily actually
5317 // return an object.
5318 if (!ReturnsRetained &&
5319 D && D->getMethodFamily() == OMF_performSelector)
5323 // Don't reclaim an object of Class type.
5324 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType())
5327 ExprNeedsCleanups = true;
5329 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject
5330 : CK_ARCReclaimReturnedObject);
5331 return ImplicitCastExpr::Create(Context, E->getType(), ck, E, nullptr,
5335 if (!getLangOpts().CPlusPlus)
5338 // Search for the base element type (cf. ASTContext::getBaseElementType) with
5339 // a fast path for the common case that the type is directly a RecordType.
5340 const Type *T = Context.getCanonicalType(E->getType().getTypePtr());
5341 const RecordType *RT = nullptr;
5343 switch (T->getTypeClass()) {
5345 RT = cast<RecordType>(T);
5347 case Type::ConstantArray:
5348 case Type::IncompleteArray:
5349 case Type::VariableArray:
5350 case Type::DependentSizedArray:
5351 T = cast<ArrayType>(T)->getElementType().getTypePtr();
5358 // That should be enough to guarantee that this type is complete, if we're
5359 // not processing a decltype expression.
5360 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
5361 if (RD->isInvalidDecl() || RD->isDependentContext())
5364 bool IsDecltype = ExprEvalContexts.back().IsDecltype;
5365 CXXDestructorDecl *Destructor = IsDecltype ? nullptr : LookupDestructor(RD);
5368 MarkFunctionReferenced(E->getExprLoc(), Destructor);
5369 CheckDestructorAccess(E->getExprLoc(), Destructor,
5370 PDiag(diag::err_access_dtor_temp)
5372 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
5375 // If destructor is trivial, we can avoid the extra copy.
5376 if (Destructor->isTrivial())
5379 // We need a cleanup, but we don't need to remember the temporary.
5380 ExprNeedsCleanups = true;
5383 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor);
5384 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E);
5387 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind);
5393 Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) {
5394 if (SubExpr.isInvalid())
5397 return MaybeCreateExprWithCleanups(SubExpr.get());
5400 Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) {
5401 assert(SubExpr && "subexpression can't be null!");
5403 CleanupVarDeclMarking();
5405 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects;
5406 assert(ExprCleanupObjects.size() >= FirstCleanup);
5407 assert(ExprNeedsCleanups || ExprCleanupObjects.size() == FirstCleanup);
5408 if (!ExprNeedsCleanups)
5411 auto Cleanups = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup,
5412 ExprCleanupObjects.size() - FirstCleanup);
5414 Expr *E = ExprWithCleanups::Create(Context, SubExpr, Cleanups);
5415 DiscardCleanupsInEvaluationContext();
5420 Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) {
5421 assert(SubStmt && "sub-statement can't be null!");
5423 CleanupVarDeclMarking();
5425 if (!ExprNeedsCleanups)
5428 // FIXME: In order to attach the temporaries, wrap the statement into
5429 // a StmtExpr; currently this is only used for asm statements.
5430 // This is hacky, either create a new CXXStmtWithTemporaries statement or
5431 // a new AsmStmtWithTemporaries.
5432 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, SubStmt,
5435 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(),
5437 return MaybeCreateExprWithCleanups(E);
5440 /// Process the expression contained within a decltype. For such expressions,
5441 /// certain semantic checks on temporaries are delayed until this point, and
5442 /// are omitted for the 'topmost' call in the decltype expression. If the
5443 /// topmost call bound a temporary, strip that temporary off the expression.
5444 ExprResult Sema::ActOnDecltypeExpression(Expr *E) {
5445 assert(ExprEvalContexts.back().IsDecltype && "not in a decltype expression");
5447 // C++11 [expr.call]p11:
5448 // If a function call is a prvalue of object type,
5449 // -- if the function call is either
5450 // -- the operand of a decltype-specifier, or
5451 // -- the right operand of a comma operator that is the operand of a
5452 // decltype-specifier,
5453 // a temporary object is not introduced for the prvalue.
5455 // Recursively rebuild ParenExprs and comma expressions to strip out the
5456 // outermost CXXBindTemporaryExpr, if any.
5457 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
5458 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr());
5459 if (SubExpr.isInvalid())
5461 if (SubExpr.get() == PE->getSubExpr())
5463 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.get());
5465 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
5466 if (BO->getOpcode() == BO_Comma) {
5467 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS());
5468 if (RHS.isInvalid())
5470 if (RHS.get() == BO->getRHS())
5472 return new (Context) BinaryOperator(
5473 BO->getLHS(), RHS.get(), BO_Comma, BO->getType(), BO->getValueKind(),
5474 BO->getObjectKind(), BO->getOperatorLoc(), BO->isFPContractable());
5478 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E);
5479 CallExpr *TopCall = TopBind ? dyn_cast<CallExpr>(TopBind->getSubExpr())
5486 // Disable the special decltype handling now.
5487 ExprEvalContexts.back().IsDecltype = false;
5489 // In MS mode, don't perform any extra checking of call return types within a
5490 // decltype expression.
5491 if (getLangOpts().MSVCCompat)
5494 // Perform the semantic checks we delayed until this point.
5495 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size();
5497 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I];
5498 if (Call == TopCall)
5501 if (CheckCallReturnType(Call->getCallReturnType(Context),
5502 Call->getLocStart(),
5503 Call, Call->getDirectCallee()))
5507 // Now all relevant types are complete, check the destructors are accessible
5508 // and non-deleted, and annotate them on the temporaries.
5509 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size();
5511 CXXBindTemporaryExpr *Bind =
5512 ExprEvalContexts.back().DelayedDecltypeBinds[I];
5513 if (Bind == TopBind)
5516 CXXTemporary *Temp = Bind->getTemporary();
5519 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
5520 CXXDestructorDecl *Destructor = LookupDestructor(RD);
5521 Temp->setDestructor(Destructor);
5523 MarkFunctionReferenced(Bind->getExprLoc(), Destructor);
5524 CheckDestructorAccess(Bind->getExprLoc(), Destructor,
5525 PDiag(diag::err_access_dtor_temp)
5526 << Bind->getType());
5527 if (DiagnoseUseOfDecl(Destructor, Bind->getExprLoc()))
5530 // We need a cleanup, but we don't need to remember the temporary.
5531 ExprNeedsCleanups = true;
5534 // Possibly strip off the top CXXBindTemporaryExpr.
5538 /// Note a set of 'operator->' functions that were used for a member access.
5539 static void noteOperatorArrows(Sema &S,
5540 ArrayRef<FunctionDecl *> OperatorArrows) {
5541 unsigned SkipStart = OperatorArrows.size(), SkipCount = 0;
5542 // FIXME: Make this configurable?
5544 if (OperatorArrows.size() > Limit) {
5545 // Produce Limit-1 normal notes and one 'skipping' note.
5546 SkipStart = (Limit - 1) / 2 + (Limit - 1) % 2;
5547 SkipCount = OperatorArrows.size() - (Limit - 1);
5550 for (unsigned I = 0; I < OperatorArrows.size(); /**/) {
5551 if (I == SkipStart) {
5552 S.Diag(OperatorArrows[I]->getLocation(),
5553 diag::note_operator_arrows_suppressed)
5557 S.Diag(OperatorArrows[I]->getLocation(), diag::note_operator_arrow_here)
5558 << OperatorArrows[I]->getCallResultType();
5564 ExprResult Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base,
5565 SourceLocation OpLoc,
5566 tok::TokenKind OpKind,
5567 ParsedType &ObjectType,
5568 bool &MayBePseudoDestructor) {
5569 // Since this might be a postfix expression, get rid of ParenListExprs.
5570 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base);
5571 if (Result.isInvalid()) return ExprError();
5572 Base = Result.get();
5574 Result = CheckPlaceholderExpr(Base);
5575 if (Result.isInvalid()) return ExprError();
5576 Base = Result.get();
5578 QualType BaseType = Base->getType();
5579 MayBePseudoDestructor = false;
5580 if (BaseType->isDependentType()) {
5581 // If we have a pointer to a dependent type and are using the -> operator,
5582 // the object type is the type that the pointer points to. We might still
5583 // have enough information about that type to do something useful.
5584 if (OpKind == tok::arrow)
5585 if (const PointerType *Ptr = BaseType->getAs<PointerType>())
5586 BaseType = Ptr->getPointeeType();
5588 ObjectType = ParsedType::make(BaseType);
5589 MayBePseudoDestructor = true;
5593 // C++ [over.match.oper]p8:
5594 // [...] When operator->returns, the operator-> is applied to the value
5595 // returned, with the original second operand.
5596 if (OpKind == tok::arrow) {
5597 QualType StartingType = BaseType;
5598 bool NoArrowOperatorFound = false;
5599 bool FirstIteration = true;
5600 FunctionDecl *CurFD = dyn_cast<FunctionDecl>(CurContext);
5601 // The set of types we've considered so far.
5602 llvm::SmallPtrSet<CanQualType,8> CTypes;
5603 SmallVector<FunctionDecl*, 8> OperatorArrows;
5604 CTypes.insert(Context.getCanonicalType(BaseType));
5606 while (BaseType->isRecordType()) {
5607 if (OperatorArrows.size() >= getLangOpts().ArrowDepth) {
5608 Diag(OpLoc, diag::err_operator_arrow_depth_exceeded)
5609 << StartingType << getLangOpts().ArrowDepth << Base->getSourceRange();
5610 noteOperatorArrows(*this, OperatorArrows);
5611 Diag(OpLoc, diag::note_operator_arrow_depth)
5612 << getLangOpts().ArrowDepth;
5616 Result = BuildOverloadedArrowExpr(
5618 // When in a template specialization and on the first loop iteration,
5619 // potentially give the default diagnostic (with the fixit in a
5620 // separate note) instead of having the error reported back to here
5621 // and giving a diagnostic with a fixit attached to the error itself.
5622 (FirstIteration && CurFD && CurFD->isFunctionTemplateSpecialization())
5624 : &NoArrowOperatorFound);
5625 if (Result.isInvalid()) {
5626 if (NoArrowOperatorFound) {
5627 if (FirstIteration) {
5628 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
5629 << BaseType << 1 << Base->getSourceRange()
5630 << FixItHint::CreateReplacement(OpLoc, ".");
5631 OpKind = tok::period;
5634 Diag(OpLoc, diag::err_typecheck_member_reference_arrow)
5635 << BaseType << Base->getSourceRange();
5636 CallExpr *CE = dyn_cast<CallExpr>(Base);
5637 if (Decl *CD = (CE ? CE->getCalleeDecl() : nullptr)) {
5638 Diag(CD->getLocStart(),
5639 diag::note_member_reference_arrow_from_operator_arrow);
5644 Base = Result.get();
5645 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base))
5646 OperatorArrows.push_back(OpCall->getDirectCallee());
5647 BaseType = Base->getType();
5648 CanQualType CBaseType = Context.getCanonicalType(BaseType);
5649 if (!CTypes.insert(CBaseType).second) {
5650 Diag(OpLoc, diag::err_operator_arrow_circular) << StartingType;
5651 noteOperatorArrows(*this, OperatorArrows);
5654 FirstIteration = false;
5657 if (OpKind == tok::arrow &&
5658 (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()))
5659 BaseType = BaseType->getPointeeType();
5662 // Objective-C properties allow "." access on Objective-C pointer types,
5663 // so adjust the base type to the object type itself.
5664 if (BaseType->isObjCObjectPointerType())
5665 BaseType = BaseType->getPointeeType();
5667 // C++ [basic.lookup.classref]p2:
5668 // [...] If the type of the object expression is of pointer to scalar
5669 // type, the unqualified-id is looked up in the context of the complete
5670 // postfix-expression.
5672 // This also indicates that we could be parsing a pseudo-destructor-name.
5673 // Note that Objective-C class and object types can be pseudo-destructor
5674 // expressions or normal member (ivar or property) access expressions.
5675 if (BaseType->isObjCObjectOrInterfaceType()) {
5676 MayBePseudoDestructor = true;
5677 } else if (!BaseType->isRecordType()) {
5678 ObjectType = ParsedType();
5679 MayBePseudoDestructor = true;
5683 // The object type must be complete (or dependent), or
5684 // C++11 [expr.prim.general]p3:
5685 // Unlike the object expression in other contexts, *this is not required to
5686 // be of complete type for purposes of class member access (5.2.5) outside
5687 // the member function body.
5688 if (!BaseType->isDependentType() &&
5689 !isThisOutsideMemberFunctionBody(BaseType) &&
5690 RequireCompleteType(OpLoc, BaseType, diag::err_incomplete_member_access))
5693 // C++ [basic.lookup.classref]p2:
5694 // If the id-expression in a class member access (5.2.5) is an
5695 // unqualified-id, and the type of the object expression is of a class
5696 // type C (or of pointer to a class type C), the unqualified-id is looked
5697 // up in the scope of class C. [...]
5698 ObjectType = ParsedType::make(BaseType);
5702 static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base,
5703 tok::TokenKind& OpKind, SourceLocation OpLoc) {
5704 if (Base->hasPlaceholderType()) {
5705 ExprResult result = S.CheckPlaceholderExpr(Base);
5706 if (result.isInvalid()) return true;
5707 Base = result.get();
5709 ObjectType = Base->getType();
5711 // C++ [expr.pseudo]p2:
5712 // The left-hand side of the dot operator shall be of scalar type. The
5713 // left-hand side of the arrow operator shall be of pointer to scalar type.
5714 // This scalar type is the object type.
5715 // Note that this is rather different from the normal handling for the
5717 if (OpKind == tok::arrow) {
5718 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) {
5719 ObjectType = Ptr->getPointeeType();
5720 } else if (!Base->isTypeDependent()) {
5721 // The user wrote "p->" when she probably meant "p."; fix it.
5722 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
5723 << ObjectType << true
5724 << FixItHint::CreateReplacement(OpLoc, ".");
5725 if (S.isSFINAEContext())
5728 OpKind = tok::period;
5735 ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base,
5736 SourceLocation OpLoc,
5737 tok::TokenKind OpKind,
5738 const CXXScopeSpec &SS,
5739 TypeSourceInfo *ScopeTypeInfo,
5740 SourceLocation CCLoc,
5741 SourceLocation TildeLoc,
5742 PseudoDestructorTypeStorage Destructed) {
5743 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo();
5745 QualType ObjectType;
5746 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
5749 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() &&
5750 !ObjectType->isVectorType()) {
5751 if (getLangOpts().MSVCCompat && ObjectType->isVoidType())
5752 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange();
5754 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar)
5755 << ObjectType << Base->getSourceRange();
5760 // C++ [expr.pseudo]p2:
5761 // [...] The cv-unqualified versions of the object type and of the type
5762 // designated by the pseudo-destructor-name shall be the same type.
5763 if (DestructedTypeInfo) {
5764 QualType DestructedType = DestructedTypeInfo->getType();
5765 SourceLocation DestructedTypeStart
5766 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin();
5767 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) {
5768 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) {
5769 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch)
5770 << ObjectType << DestructedType << Base->getSourceRange()
5771 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
5773 // Recover by setting the destructed type to the object type.
5774 DestructedType = ObjectType;
5775 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType,
5776 DestructedTypeStart);
5777 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
5778 } else if (DestructedType.getObjCLifetime() !=
5779 ObjectType.getObjCLifetime()) {
5781 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) {
5782 // Okay: just pretend that the user provided the correctly-qualified
5785 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals)
5786 << ObjectType << DestructedType << Base->getSourceRange()
5787 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
5790 // Recover by setting the destructed type to the object type.
5791 DestructedType = ObjectType;
5792 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType,
5793 DestructedTypeStart);
5794 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
5799 // C++ [expr.pseudo]p2:
5800 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the
5803 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name
5805 // shall designate the same scalar type.
5806 if (ScopeTypeInfo) {
5807 QualType ScopeType = ScopeTypeInfo->getType();
5808 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() &&
5809 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) {
5811 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(),
5812 diag::err_pseudo_dtor_type_mismatch)
5813 << ObjectType << ScopeType << Base->getSourceRange()
5814 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange();
5816 ScopeType = QualType();
5817 ScopeTypeInfo = nullptr;
5822 = new (Context) CXXPseudoDestructorExpr(Context, Base,
5823 OpKind == tok::arrow, OpLoc,
5824 SS.getWithLocInContext(Context),
5833 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
5834 SourceLocation OpLoc,
5835 tok::TokenKind OpKind,
5837 UnqualifiedId &FirstTypeName,
5838 SourceLocation CCLoc,
5839 SourceLocation TildeLoc,
5840 UnqualifiedId &SecondTypeName) {
5841 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
5842 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
5843 "Invalid first type name in pseudo-destructor");
5844 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
5845 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
5846 "Invalid second type name in pseudo-destructor");
5848 QualType ObjectType;
5849 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
5852 // Compute the object type that we should use for name lookup purposes. Only
5853 // record types and dependent types matter.
5854 ParsedType ObjectTypePtrForLookup;
5856 if (ObjectType->isRecordType())
5857 ObjectTypePtrForLookup = ParsedType::make(ObjectType);
5858 else if (ObjectType->isDependentType())
5859 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy);
5862 // Convert the name of the type being destructed (following the ~) into a
5863 // type (with source-location information).
5864 QualType DestructedType;
5865 TypeSourceInfo *DestructedTypeInfo = nullptr;
5866 PseudoDestructorTypeStorage Destructed;
5867 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) {
5868 ParsedType T = getTypeName(*SecondTypeName.Identifier,
5869 SecondTypeName.StartLocation,
5870 S, &SS, true, false, ObjectTypePtrForLookup);
5872 ((SS.isSet() && !computeDeclContext(SS, false)) ||
5873 (!SS.isSet() && ObjectType->isDependentType()))) {
5874 // The name of the type being destroyed is a dependent name, and we
5875 // couldn't find anything useful in scope. Just store the identifier and
5876 // it's location, and we'll perform (qualified) name lookup again at
5877 // template instantiation time.
5878 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier,
5879 SecondTypeName.StartLocation);
5881 Diag(SecondTypeName.StartLocation,
5882 diag::err_pseudo_dtor_destructor_non_type)
5883 << SecondTypeName.Identifier << ObjectType;
5884 if (isSFINAEContext())
5887 // Recover by assuming we had the right type all along.
5888 DestructedType = ObjectType;
5890 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo);
5892 // Resolve the template-id to a type.
5893 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId;
5894 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
5895 TemplateId->NumArgs);
5896 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
5897 TemplateId->TemplateKWLoc,
5898 TemplateId->Template,
5899 TemplateId->TemplateNameLoc,
5900 TemplateId->LAngleLoc,
5902 TemplateId->RAngleLoc);
5903 if (T.isInvalid() || !T.get()) {
5904 // Recover by assuming we had the right type all along.
5905 DestructedType = ObjectType;
5907 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo);
5910 // If we've performed some kind of recovery, (re-)build the type source
5912 if (!DestructedType.isNull()) {
5913 if (!DestructedTypeInfo)
5914 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType,
5915 SecondTypeName.StartLocation);
5916 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
5919 // Convert the name of the scope type (the type prior to '::') into a type.
5920 TypeSourceInfo *ScopeTypeInfo = nullptr;
5922 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
5923 FirstTypeName.Identifier) {
5924 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) {
5925 ParsedType T = getTypeName(*FirstTypeName.Identifier,
5926 FirstTypeName.StartLocation,
5927 S, &SS, true, false, ObjectTypePtrForLookup);
5929 Diag(FirstTypeName.StartLocation,
5930 diag::err_pseudo_dtor_destructor_non_type)
5931 << FirstTypeName.Identifier << ObjectType;
5933 if (isSFINAEContext())
5936 // Just drop this type. It's unnecessary anyway.
5937 ScopeType = QualType();
5939 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo);
5941 // Resolve the template-id to a type.
5942 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId;
5943 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
5944 TemplateId->NumArgs);
5945 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
5946 TemplateId->TemplateKWLoc,
5947 TemplateId->Template,
5948 TemplateId->TemplateNameLoc,
5949 TemplateId->LAngleLoc,
5951 TemplateId->RAngleLoc);
5952 if (T.isInvalid() || !T.get()) {
5953 // Recover by dropping this type.
5954 ScopeType = QualType();
5956 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo);
5960 if (!ScopeType.isNull() && !ScopeTypeInfo)
5961 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType,
5962 FirstTypeName.StartLocation);
5965 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS,
5966 ScopeTypeInfo, CCLoc, TildeLoc,
5970 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
5971 SourceLocation OpLoc,
5972 tok::TokenKind OpKind,
5973 SourceLocation TildeLoc,
5974 const DeclSpec& DS) {
5975 QualType ObjectType;
5976 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
5979 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc(),
5983 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T);
5984 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc());
5985 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T);
5986 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo);
5988 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(),
5989 nullptr, SourceLocation(), TildeLoc,
5993 ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl,
5994 CXXConversionDecl *Method,
5995 bool HadMultipleCandidates) {
5996 if (Method->getParent()->isLambda() &&
5997 Method->getConversionType()->isBlockPointerType()) {
5998 // This is a lambda coversion to block pointer; check if the argument
6001 CastExpr *CE = dyn_cast<CastExpr>(SubE);
6002 if (CE && CE->getCastKind() == CK_NoOp)
6003 SubE = CE->getSubExpr();
6004 SubE = SubE->IgnoreParens();
6005 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE))
6006 SubE = BE->getSubExpr();
6007 if (isa<LambdaExpr>(SubE)) {
6008 // For the conversion to block pointer on a lambda expression, we
6009 // construct a special BlockLiteral instead; this doesn't really make
6010 // a difference in ARC, but outside of ARC the resulting block literal
6011 // follows the normal lifetime rules for block literals instead of being
6013 DiagnosticErrorTrap Trap(Diags);
6014 ExprResult Exp = BuildBlockForLambdaConversion(E->getExprLoc(),
6017 if (Exp.isInvalid())
6018 Diag(E->getExprLoc(), diag::note_lambda_to_block_conv);
6023 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/nullptr,
6025 if (Exp.isInvalid())
6028 MemberExpr *ME = new (Context) MemberExpr(
6029 Exp.get(), /*IsArrow=*/false, SourceLocation(), Method, SourceLocation(),
6030 Context.BoundMemberTy, VK_RValue, OK_Ordinary);
6031 if (HadMultipleCandidates)
6032 ME->setHadMultipleCandidates(true);
6033 MarkMemberReferenced(ME);
6035 QualType ResultType = Method->getReturnType();
6036 ExprValueKind VK = Expr::getValueKindForType(ResultType);
6037 ResultType = ResultType.getNonLValueExprType(Context);
6039 CXXMemberCallExpr *CE =
6040 new (Context) CXXMemberCallExpr(Context, ME, None, ResultType, VK,
6041 Exp.get()->getLocEnd());
6045 ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand,
6046 SourceLocation RParen) {
6047 // If the operand is an unresolved lookup expression, the expression is ill-
6048 // formed per [over.over]p1, because overloaded function names cannot be used
6049 // without arguments except in explicit contexts.
6050 ExprResult R = CheckPlaceholderExpr(Operand);
6054 // The operand may have been modified when checking the placeholder type.
6057 if (ActiveTemplateInstantiations.empty() &&
6058 Operand->HasSideEffects(Context, false)) {
6059 // The expression operand for noexcept is in an unevaluated expression
6060 // context, so side effects could result in unintended consequences.
6061 Diag(Operand->getExprLoc(), diag::warn_side_effects_unevaluated_context);
6064 CanThrowResult CanThrow = canThrow(Operand);
6065 return new (Context)
6066 CXXNoexceptExpr(Context.BoolTy, Operand, CanThrow, KeyLoc, RParen);
6069 ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation,
6070 Expr *Operand, SourceLocation RParen) {
6071 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen);
6074 static bool IsSpecialDiscardedValue(Expr *E) {
6075 // In C++11, discarded-value expressions of a certain form are special,
6076 // according to [expr]p10:
6077 // The lvalue-to-rvalue conversion (4.1) is applied only if the
6078 // expression is an lvalue of volatile-qualified type and it has
6079 // one of the following forms:
6080 E = E->IgnoreParens();
6082 // - id-expression (5.1.1),
6083 if (isa<DeclRefExpr>(E))
6086 // - subscripting (5.2.1),
6087 if (isa<ArraySubscriptExpr>(E))
6090 // - class member access (5.2.5),
6091 if (isa<MemberExpr>(E))
6094 // - indirection (5.3.1),
6095 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E))
6096 if (UO->getOpcode() == UO_Deref)
6099 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
6100 // - pointer-to-member operation (5.5),
6101 if (BO->isPtrMemOp())
6104 // - comma expression (5.18) where the right operand is one of the above.
6105 if (BO->getOpcode() == BO_Comma)
6106 return IsSpecialDiscardedValue(BO->getRHS());
6109 // - conditional expression (5.16) where both the second and the third
6110 // operands are one of the above, or
6111 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E))
6112 return IsSpecialDiscardedValue(CO->getTrueExpr()) &&
6113 IsSpecialDiscardedValue(CO->getFalseExpr());
6114 // The related edge case of "*x ?: *x".
6115 if (BinaryConditionalOperator *BCO =
6116 dyn_cast<BinaryConditionalOperator>(E)) {
6117 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(BCO->getTrueExpr()))
6118 return IsSpecialDiscardedValue(OVE->getSourceExpr()) &&
6119 IsSpecialDiscardedValue(BCO->getFalseExpr());
6122 // Objective-C++ extensions to the rule.
6123 if (isa<PseudoObjectExpr>(E) || isa<ObjCIvarRefExpr>(E))
6129 /// Perform the conversions required for an expression used in a
6130 /// context that ignores the result.
6131 ExprResult Sema::IgnoredValueConversions(Expr *E) {
6132 if (E->hasPlaceholderType()) {
6133 ExprResult result = CheckPlaceholderExpr(E);
6134 if (result.isInvalid()) return E;
6139 // [Except in specific positions,] an lvalue that does not have
6140 // array type is converted to the value stored in the
6141 // designated object (and is no longer an lvalue).
6142 if (E->isRValue()) {
6143 // In C, function designators (i.e. expressions of function type)
6144 // are r-values, but we still want to do function-to-pointer decay
6145 // on them. This is both technically correct and convenient for
6147 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType())
6148 return DefaultFunctionArrayConversion(E);
6153 if (getLangOpts().CPlusPlus) {
6154 // The C++11 standard defines the notion of a discarded-value expression;
6155 // normally, we don't need to do anything to handle it, but if it is a
6156 // volatile lvalue with a special form, we perform an lvalue-to-rvalue
6158 if (getLangOpts().CPlusPlus11 && E->isGLValue() &&
6159 E->getType().isVolatileQualified() &&
6160 IsSpecialDiscardedValue(E)) {
6161 ExprResult Res = DefaultLvalueConversion(E);
6162 if (Res.isInvalid())
6169 // GCC seems to also exclude expressions of incomplete enum type.
6170 if (const EnumType *T = E->getType()->getAs<EnumType>()) {
6171 if (!T->getDecl()->isComplete()) {
6172 // FIXME: stupid workaround for a codegen bug!
6173 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).get();
6178 ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
6179 if (Res.isInvalid())
6183 if (!E->getType()->isVoidType())
6184 RequireCompleteType(E->getExprLoc(), E->getType(),
6185 diag::err_incomplete_type);
6189 // If we can unambiguously determine whether Var can never be used
6190 // in a constant expression, return true.
6191 // - if the variable and its initializer are non-dependent, then
6192 // we can unambiguously check if the variable is a constant expression.
6193 // - if the initializer is not value dependent - we can determine whether
6194 // it can be used to initialize a constant expression. If Init can not
6195 // be used to initialize a constant expression we conclude that Var can
6196 // never be a constant expression.
6197 // - FXIME: if the initializer is dependent, we can still do some analysis and
6198 // identify certain cases unambiguously as non-const by using a Visitor:
6199 // - such as those that involve odr-use of a ParmVarDecl, involve a new
6200 // delete, lambda-expr, dynamic-cast, reinterpret-cast etc...
6201 static inline bool VariableCanNeverBeAConstantExpression(VarDecl *Var,
6202 ASTContext &Context) {
6203 if (isa<ParmVarDecl>(Var)) return true;
6204 const VarDecl *DefVD = nullptr;
6206 // If there is no initializer - this can not be a constant expression.
6207 if (!Var->getAnyInitializer(DefVD)) return true;
6209 if (DefVD->isWeak()) return false;
6210 EvaluatedStmt *Eval = DefVD->ensureEvaluatedStmt();
6212 Expr *Init = cast<Expr>(Eval->Value);
6214 if (Var->getType()->isDependentType() || Init->isValueDependent()) {
6215 // FIXME: Teach the constant evaluator to deal with the non-dependent parts
6216 // of value-dependent expressions, and use it here to determine whether the
6217 // initializer is a potential constant expression.
6221 return !IsVariableAConstantExpression(Var, Context);
6224 /// \brief Check if the current lambda has any potential captures
6225 /// that must be captured by any of its enclosing lambdas that are ready to
6226 /// capture. If there is a lambda that can capture a nested
6227 /// potential-capture, go ahead and do so. Also, check to see if any
6228 /// variables are uncaptureable or do not involve an odr-use so do not
6229 /// need to be captured.
6231 static void CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(
6232 Expr *const FE, LambdaScopeInfo *const CurrentLSI, Sema &S) {
6234 assert(!S.isUnevaluatedContext());
6235 assert(S.CurContext->isDependentContext());
6236 assert(CurrentLSI->CallOperator == S.CurContext &&
6237 "The current call operator must be synchronized with Sema's CurContext");
6239 const bool IsFullExprInstantiationDependent = FE->isInstantiationDependent();
6241 ArrayRef<const FunctionScopeInfo *> FunctionScopesArrayRef(
6242 S.FunctionScopes.data(), S.FunctionScopes.size());
6244 // All the potentially captureable variables in the current nested
6245 // lambda (within a generic outer lambda), must be captured by an
6246 // outer lambda that is enclosed within a non-dependent context.
6247 const unsigned NumPotentialCaptures =
6248 CurrentLSI->getNumPotentialVariableCaptures();
6249 for (unsigned I = 0; I != NumPotentialCaptures; ++I) {
6250 Expr *VarExpr = nullptr;
6251 VarDecl *Var = nullptr;
6252 CurrentLSI->getPotentialVariableCapture(I, Var, VarExpr);
6253 // If the variable is clearly identified as non-odr-used and the full
6254 // expression is not instantiation dependent, only then do we not
6255 // need to check enclosing lambda's for speculative captures.
6257 // Even though 'x' is not odr-used, it should be captured.
6259 // const int x = 10;
6260 // auto L = [=](auto a) {
6264 if (CurrentLSI->isVariableExprMarkedAsNonODRUsed(VarExpr) &&
6265 !IsFullExprInstantiationDependent)
6268 // If we have a capture-capable lambda for the variable, go ahead and
6269 // capture the variable in that lambda (and all its enclosing lambdas).
6270 if (const Optional<unsigned> Index =
6271 getStackIndexOfNearestEnclosingCaptureCapableLambda(
6272 FunctionScopesArrayRef, Var, S)) {
6273 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
6274 MarkVarDeclODRUsed(Var, VarExpr->getExprLoc(), S,
6275 &FunctionScopeIndexOfCapturableLambda);
6277 const bool IsVarNeverAConstantExpression =
6278 VariableCanNeverBeAConstantExpression(Var, S.Context);
6279 if (!IsFullExprInstantiationDependent || IsVarNeverAConstantExpression) {
6280 // This full expression is not instantiation dependent or the variable
6281 // can not be used in a constant expression - which means
6282 // this variable must be odr-used here, so diagnose a
6283 // capture violation early, if the variable is un-captureable.
6284 // This is purely for diagnosing errors early. Otherwise, this
6285 // error would get diagnosed when the lambda becomes capture ready.
6286 QualType CaptureType, DeclRefType;
6287 SourceLocation ExprLoc = VarExpr->getExprLoc();
6288 if (S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
6289 /*EllipsisLoc*/ SourceLocation(),
6290 /*BuildAndDiagnose*/false, CaptureType,
6291 DeclRefType, nullptr)) {
6292 // We will never be able to capture this variable, and we need
6293 // to be able to in any and all instantiations, so diagnose it.
6294 S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
6295 /*EllipsisLoc*/ SourceLocation(),
6296 /*BuildAndDiagnose*/true, CaptureType,
6297 DeclRefType, nullptr);
6302 // Check if 'this' needs to be captured.
6303 if (CurrentLSI->hasPotentialThisCapture()) {
6304 // If we have a capture-capable lambda for 'this', go ahead and capture
6305 // 'this' in that lambda (and all its enclosing lambdas).
6306 if (const Optional<unsigned> Index =
6307 getStackIndexOfNearestEnclosingCaptureCapableLambda(
6308 FunctionScopesArrayRef, /*0 is 'this'*/ nullptr, S)) {
6309 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
6310 S.CheckCXXThisCapture(CurrentLSI->PotentialThisCaptureLocation,
6311 /*Explicit*/ false, /*BuildAndDiagnose*/ true,
6312 &FunctionScopeIndexOfCapturableLambda);
6316 // Reset all the potential captures at the end of each full-expression.
6317 CurrentLSI->clearPotentialCaptures();
6320 static ExprResult attemptRecovery(Sema &SemaRef,
6321 const TypoCorrectionConsumer &Consumer,
6322 TypoCorrection TC) {
6323 LookupResult R(SemaRef, Consumer.getLookupResult().getLookupNameInfo(),
6324 Consumer.getLookupResult().getLookupKind());
6325 const CXXScopeSpec *SS = Consumer.getSS();
6328 // Use an approprate CXXScopeSpec for building the expr.
6329 if (auto *NNS = TC.getCorrectionSpecifier())
6330 NewSS.MakeTrivial(SemaRef.Context, NNS, TC.getCorrectionRange());
6331 else if (SS && !TC.WillReplaceSpecifier())
6334 if (auto *ND = TC.getCorrectionDecl()) {
6335 R.setLookupName(ND->getDeclName());
6337 if (ND->isCXXClassMember()) {
6338 // Figure out the correct naming class to add to the LookupResult.
6339 CXXRecordDecl *Record = nullptr;
6340 if (auto *NNS = TC.getCorrectionSpecifier())
6341 Record = NNS->getAsType()->getAsCXXRecordDecl();
6344 dyn_cast<CXXRecordDecl>(ND->getDeclContext()->getRedeclContext());
6346 R.setNamingClass(Record);
6348 // Detect and handle the case where the decl might be an implicit
6350 bool MightBeImplicitMember;
6351 if (!Consumer.isAddressOfOperand())
6352 MightBeImplicitMember = true;
6353 else if (!NewSS.isEmpty())
6354 MightBeImplicitMember = false;
6355 else if (R.isOverloadedResult())
6356 MightBeImplicitMember = false;
6357 else if (R.isUnresolvableResult())
6358 MightBeImplicitMember = true;
6360 MightBeImplicitMember = isa<FieldDecl>(ND) ||
6361 isa<IndirectFieldDecl>(ND) ||
6362 isa<MSPropertyDecl>(ND);
6364 if (MightBeImplicitMember)
6365 return SemaRef.BuildPossibleImplicitMemberExpr(
6366 NewSS, /*TemplateKWLoc*/ SourceLocation(), R,
6367 /*TemplateArgs*/ nullptr);
6368 } else if (auto *Ivar = dyn_cast<ObjCIvarDecl>(ND)) {
6369 return SemaRef.LookupInObjCMethod(R, Consumer.getScope(),
6370 Ivar->getIdentifier());
6374 return SemaRef.BuildDeclarationNameExpr(NewSS, R, /*NeedsADL*/ false,
6375 /*AcceptInvalidDecl*/ true);
6379 class FindTypoExprs : public RecursiveASTVisitor<FindTypoExprs> {
6380 llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs;
6383 explicit FindTypoExprs(llvm::SmallSetVector<TypoExpr *, 2> &TypoExprs)
6384 : TypoExprs(TypoExprs) {}
6385 bool VisitTypoExpr(TypoExpr *TE) {
6386 TypoExprs.insert(TE);
6391 class TransformTypos : public TreeTransform<TransformTypos> {
6392 typedef TreeTransform<TransformTypos> BaseTransform;
6394 VarDecl *InitDecl; // A decl to avoid as a correction because it is in the
6395 // process of being initialized.
6396 llvm::function_ref<ExprResult(Expr *)> ExprFilter;
6397 llvm::SmallSetVector<TypoExpr *, 2> TypoExprs, AmbiguousTypoExprs;
6398 llvm::SmallDenseMap<TypoExpr *, ExprResult, 2> TransformCache;
6399 llvm::SmallDenseMap<OverloadExpr *, Expr *, 4> OverloadResolution;
6401 /// \brief Emit diagnostics for all of the TypoExprs encountered.
6402 /// If the TypoExprs were successfully corrected, then the diagnostics should
6403 /// suggest the corrections. Otherwise the diagnostics will not suggest
6404 /// anything (having been passed an empty TypoCorrection).
6405 void EmitAllDiagnostics() {
6406 for (auto E : TypoExprs) {
6407 TypoExpr *TE = cast<TypoExpr>(E);
6408 auto &State = SemaRef.getTypoExprState(TE);
6409 if (State.DiagHandler) {
6410 TypoCorrection TC = State.Consumer->getCurrentCorrection();
6411 ExprResult Replacement = TransformCache[TE];
6413 // Extract the NamedDecl from the transformed TypoExpr and add it to the
6414 // TypoCorrection, replacing the existing decls. This ensures the right
6415 // NamedDecl is used in diagnostics e.g. in the case where overload
6416 // resolution was used to select one from several possible decls that
6417 // had been stored in the TypoCorrection.
6418 if (auto *ND = getDeclFromExpr(
6419 Replacement.isInvalid() ? nullptr : Replacement.get()))
6420 TC.setCorrectionDecl(ND);
6422 State.DiagHandler(TC);
6424 SemaRef.clearDelayedTypo(TE);
6428 /// \brief If corrections for the first TypoExpr have been exhausted for a
6429 /// given combination of the other TypoExprs, retry those corrections against
6430 /// the next combination of substitutions for the other TypoExprs by advancing
6431 /// to the next potential correction of the second TypoExpr. For the second
6432 /// and subsequent TypoExprs, if its stream of corrections has been exhausted,
6433 /// the stream is reset and the next TypoExpr's stream is advanced by one (a
6434 /// TypoExpr's correction stream is advanced by removing the TypoExpr from the
6435 /// TransformCache). Returns true if there is still any untried combinations
6437 bool CheckAndAdvanceTypoExprCorrectionStreams() {
6438 for (auto TE : TypoExprs) {
6439 auto &State = SemaRef.getTypoExprState(TE);
6440 TransformCache.erase(TE);
6441 if (!State.Consumer->finished())
6443 State.Consumer->resetCorrectionStream();
6448 NamedDecl *getDeclFromExpr(Expr *E) {
6449 if (auto *OE = dyn_cast_or_null<OverloadExpr>(E))
6450 E = OverloadResolution[OE];
6454 if (auto *DRE = dyn_cast<DeclRefExpr>(E))
6455 return DRE->getDecl();
6456 if (auto *ME = dyn_cast<MemberExpr>(E))
6457 return ME->getMemberDecl();
6458 // FIXME: Add any other expr types that could be be seen by the delayed typo
6459 // correction TreeTransform for which the corresponding TypoCorrection could
6460 // contain multiple decls.
6464 ExprResult TryTransform(Expr *E) {
6465 Sema::SFINAETrap Trap(SemaRef);
6466 ExprResult Res = TransformExpr(E);
6467 if (Trap.hasErrorOccurred() || Res.isInvalid())
6470 return ExprFilter(Res.get());
6474 TransformTypos(Sema &SemaRef, VarDecl *InitDecl, llvm::function_ref<ExprResult(Expr *)> Filter)
6475 : BaseTransform(SemaRef), InitDecl(InitDecl), ExprFilter(Filter) {}
6477 ExprResult RebuildCallExpr(Expr *Callee, SourceLocation LParenLoc,
6479 SourceLocation RParenLoc,
6480 Expr *ExecConfig = nullptr) {
6481 auto Result = BaseTransform::RebuildCallExpr(Callee, LParenLoc, Args,
6482 RParenLoc, ExecConfig);
6483 if (auto *OE = dyn_cast<OverloadExpr>(Callee)) {
6484 if (Result.isUsable()) {
6485 Expr *ResultCall = Result.get();
6486 if (auto *BE = dyn_cast<CXXBindTemporaryExpr>(ResultCall))
6487 ResultCall = BE->getSubExpr();
6488 if (auto *CE = dyn_cast<CallExpr>(ResultCall))
6489 OverloadResolution[OE] = CE->getCallee();
6495 ExprResult TransformLambdaExpr(LambdaExpr *E) { return Owned(E); }
6497 ExprResult Transform(Expr *E) {
6500 Res = TryTransform(E);
6502 // Exit if either the transform was valid or if there were no TypoExprs
6503 // to transform that still have any untried correction candidates..
6504 if (!Res.isInvalid() ||
6505 !CheckAndAdvanceTypoExprCorrectionStreams())
6509 // Ensure none of the TypoExprs have multiple typo correction candidates
6510 // with the same edit length that pass all the checks and filters.
6511 // TODO: Properly handle various permutations of possible corrections when
6512 // there is more than one potentially ambiguous typo correction.
6513 // Also, disable typo correction while attempting the transform when
6514 // handling potentially ambiguous typo corrections as any new TypoExprs will
6515 // have been introduced by the application of one of the correction
6516 // candidates and add little to no value if corrected.
6517 SemaRef.DisableTypoCorrection = true;
6518 while (!AmbiguousTypoExprs.empty()) {
6519 auto TE = AmbiguousTypoExprs.back();
6520 auto Cached = TransformCache[TE];
6521 auto &State = SemaRef.getTypoExprState(TE);
6522 State.Consumer->saveCurrentPosition();
6523 TransformCache.erase(TE);
6524 if (!TryTransform(E).isInvalid()) {
6525 State.Consumer->resetCorrectionStream();
6526 TransformCache.erase(TE);
6530 AmbiguousTypoExprs.remove(TE);
6531 State.Consumer->restoreSavedPosition();
6532 TransformCache[TE] = Cached;
6534 SemaRef.DisableTypoCorrection = false;
6536 // Ensure that all of the TypoExprs within the current Expr have been found.
6537 if (!Res.isUsable())
6538 FindTypoExprs(TypoExprs).TraverseStmt(E);
6540 EmitAllDiagnostics();
6545 ExprResult TransformTypoExpr(TypoExpr *E) {
6546 // If the TypoExpr hasn't been seen before, record it. Otherwise, return the
6547 // cached transformation result if there is one and the TypoExpr isn't the
6548 // first one that was encountered.
6549 auto &CacheEntry = TransformCache[E];
6550 if (!TypoExprs.insert(E) && !CacheEntry.isUnset()) {
6554 auto &State = SemaRef.getTypoExprState(E);
6555 assert(State.Consumer && "Cannot transform a cleared TypoExpr");
6557 // For the first TypoExpr and an uncached TypoExpr, find the next likely
6558 // typo correction and return it.
6559 while (TypoCorrection TC = State.Consumer->getNextCorrection()) {
6560 if (InitDecl && TC.getCorrectionDecl() == InitDecl)
6562 ExprResult NE = State.RecoveryHandler ?
6563 State.RecoveryHandler(SemaRef, E, TC) :
6564 attemptRecovery(SemaRef, *State.Consumer, TC);
6565 if (!NE.isInvalid()) {
6566 // Check whether there may be a second viable correction with the same
6567 // edit distance; if so, remember this TypoExpr may have an ambiguous
6568 // correction so it can be more thoroughly vetted later.
6569 TypoCorrection Next;
6570 if ((Next = State.Consumer->peekNextCorrection()) &&
6571 Next.getEditDistance(false) == TC.getEditDistance(false)) {
6572 AmbiguousTypoExprs.insert(E);
6574 AmbiguousTypoExprs.remove(E);
6576 assert(!NE.isUnset() &&
6577 "Typo was transformed into a valid-but-null ExprResult");
6578 return CacheEntry = NE;
6581 return CacheEntry = ExprError();
6587 Sema::CorrectDelayedTyposInExpr(Expr *E, VarDecl *InitDecl,
6588 llvm::function_ref<ExprResult(Expr *)> Filter) {
6589 // If the current evaluation context indicates there are uncorrected typos
6590 // and the current expression isn't guaranteed to not have typos, try to
6591 // resolve any TypoExpr nodes that might be in the expression.
6592 if (E && !ExprEvalContexts.empty() && ExprEvalContexts.back().NumTypos &&
6593 (E->isTypeDependent() || E->isValueDependent() ||
6594 E->isInstantiationDependent())) {
6595 auto TyposInContext = ExprEvalContexts.back().NumTypos;
6596 assert(TyposInContext < ~0U && "Recursive call of CorrectDelayedTyposInExpr");
6597 ExprEvalContexts.back().NumTypos = ~0U;
6598 auto TyposResolved = DelayedTypos.size();
6599 auto Result = TransformTypos(*this, InitDecl, Filter).Transform(E);
6600 ExprEvalContexts.back().NumTypos = TyposInContext;
6601 TyposResolved -= DelayedTypos.size();
6602 if (Result.isInvalid() || Result.get() != E) {
6603 ExprEvalContexts.back().NumTypos -= TyposResolved;
6606 assert(TyposResolved == 0 && "Corrected typo but got same Expr back?");
6611 ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC,
6612 bool DiscardedValue,
6614 bool IsLambdaInitCaptureInitializer) {
6615 ExprResult FullExpr = FE;
6617 if (!FullExpr.get())
6620 // If we are an init-expression in a lambdas init-capture, we should not
6621 // diagnose an unexpanded pack now (will be diagnosed once lambda-expr
6622 // containing full-expression is done).
6623 // template<class ... Ts> void test(Ts ... t) {
6624 // test([&a(t)]() { <-- (t) is an init-expr that shouldn't be diagnosed now.
6628 // FIXME: This is a hack. It would be better if we pushed the lambda scope
6629 // when we parse the lambda introducer, and teach capturing (but not
6630 // unexpanded pack detection) to walk over LambdaScopeInfos which don't have a
6631 // corresponding class yet (that is, have LambdaScopeInfo either represent a
6632 // lambda where we've entered the introducer but not the body, or represent a
6633 // lambda where we've entered the body, depending on where the
6634 // parser/instantiation has got to).
6635 if (!IsLambdaInitCaptureInitializer &&
6636 DiagnoseUnexpandedParameterPack(FullExpr.get()))
6639 // Top-level expressions default to 'id' when we're in a debugger.
6640 if (DiscardedValue && getLangOpts().DebuggerCastResultToId &&
6641 FullExpr.get()->getType() == Context.UnknownAnyTy) {
6642 FullExpr = forceUnknownAnyToType(FullExpr.get(), Context.getObjCIdType());
6643 if (FullExpr.isInvalid())
6647 if (DiscardedValue) {
6648 FullExpr = CheckPlaceholderExpr(FullExpr.get());
6649 if (FullExpr.isInvalid())
6652 FullExpr = IgnoredValueConversions(FullExpr.get());
6653 if (FullExpr.isInvalid())
6657 FullExpr = CorrectDelayedTyposInExpr(FullExpr.get());
6658 if (FullExpr.isInvalid())
6661 CheckCompletedExpr(FullExpr.get(), CC, IsConstexpr);
6663 // At the end of this full expression (which could be a deeply nested
6664 // lambda), if there is a potential capture within the nested lambda,
6665 // have the outer capture-able lambda try and capture it.
6666 // Consider the following code:
6667 // void f(int, int);
6668 // void f(const int&, double);
6670 // const int x = 10, y = 20;
6671 // auto L = [=](auto a) {
6672 // auto M = [=](auto b) {
6673 // f(x, b); <-- requires x to be captured by L and M
6674 // f(y, a); <-- requires y to be captured by L, but not all Ms
6679 // FIXME: Also consider what happens for something like this that involves
6680 // the gnu-extension statement-expressions or even lambda-init-captures:
6683 // auto L = [&](auto a) {
6684 // +n + ({ 0; a; });
6688 // Here, we see +n, and then the full-expression 0; ends, so we don't
6689 // capture n (and instead remove it from our list of potential captures),
6690 // and then the full-expression +n + ({ 0; }); ends, but it's too late
6691 // for us to see that we need to capture n after all.
6693 LambdaScopeInfo *const CurrentLSI = getCurLambda();
6694 // FIXME: PR 17877 showed that getCurLambda() can return a valid pointer
6695 // even if CurContext is not a lambda call operator. Refer to that Bug Report
6696 // for an example of the code that might cause this asynchrony.
6697 // By ensuring we are in the context of a lambda's call operator
6698 // we can fix the bug (we only need to check whether we need to capture
6699 // if we are within a lambda's body); but per the comments in that
6700 // PR, a proper fix would entail :
6701 // "Alternative suggestion:
6702 // - Add to Sema an integer holding the smallest (outermost) scope
6703 // index that we are *lexically* within, and save/restore/set to
6704 // FunctionScopes.size() in InstantiatingTemplate's
6705 // constructor/destructor.
6706 // - Teach the handful of places that iterate over FunctionScopes to
6707 // stop at the outermost enclosing lexical scope."
6708 const bool IsInLambdaDeclContext = isLambdaCallOperator(CurContext);
6709 if (IsInLambdaDeclContext && CurrentLSI &&
6710 CurrentLSI->hasPotentialCaptures() && !FullExpr.isInvalid())
6711 CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(FE, CurrentLSI,
6713 return MaybeCreateExprWithCleanups(FullExpr);
6716 StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) {
6717 if (!FullStmt) return StmtError();
6719 return MaybeCreateStmtWithCleanups(FullStmt);
6722 Sema::IfExistsResult
6723 Sema::CheckMicrosoftIfExistsSymbol(Scope *S,
6725 const DeclarationNameInfo &TargetNameInfo) {
6726 DeclarationName TargetName = TargetNameInfo.getName();
6728 return IER_DoesNotExist;
6730 // If the name itself is dependent, then the result is dependent.
6731 if (TargetName.isDependentName())
6732 return IER_Dependent;
6734 // Do the redeclaration lookup in the current scope.
6735 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName,
6736 Sema::NotForRedeclaration);
6737 LookupParsedName(R, S, &SS);
6738 R.suppressDiagnostics();
6740 switch (R.getResultKind()) {
6741 case LookupResult::Found:
6742 case LookupResult::FoundOverloaded:
6743 case LookupResult::FoundUnresolvedValue:
6744 case LookupResult::Ambiguous:
6747 case LookupResult::NotFound:
6748 return IER_DoesNotExist;
6750 case LookupResult::NotFoundInCurrentInstantiation:
6751 return IER_Dependent;
6754 llvm_unreachable("Invalid LookupResult Kind!");
6757 Sema::IfExistsResult
6758 Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc,
6759 bool IsIfExists, CXXScopeSpec &SS,
6760 UnqualifiedId &Name) {
6761 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
6763 // Check for unexpanded parameter packs.
6764 SmallVector<UnexpandedParameterPack, 4> Unexpanded;
6765 collectUnexpandedParameterPacks(SS, Unexpanded);
6766 collectUnexpandedParameterPacks(TargetNameInfo, Unexpanded);
6767 if (!Unexpanded.empty()) {
6768 DiagnoseUnexpandedParameterPacks(KeywordLoc,
6769 IsIfExists? UPPC_IfExists
6775 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo);