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 "TypeLocBuilder.h"
17 #include "clang/AST/ASTContext.h"
18 #include "clang/AST/ASTLambda.h"
19 #include "clang/AST/CXXInheritance.h"
20 #include "clang/AST/CharUnits.h"
21 #include "clang/AST/DeclObjC.h"
22 #include "clang/AST/EvaluatedExprVisitor.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::Namespace:
71 case NestedNameSpecifier::NamespaceAlias:
72 llvm_unreachable("Nested name specifier is not a type for inheriting ctor");
75 // This reference to the type is located entirely at the location of the
76 // final identifier in the qualified-id.
77 return CreateParsedType(Type,
78 Context.getTrivialTypeSourceInfo(Type, NameLoc));
81 ParsedType Sema::getDestructorName(SourceLocation TildeLoc,
83 SourceLocation NameLoc,
84 Scope *S, CXXScopeSpec &SS,
85 ParsedType ObjectTypePtr,
86 bool EnteringContext) {
87 // Determine where to perform name lookup.
89 // FIXME: This area of the standard is very messy, and the current
90 // wording is rather unclear about which scopes we search for the
91 // destructor name; see core issues 399 and 555. Issue 399 in
92 // particular shows where the current description of destructor name
93 // lookup is completely out of line with existing practice, e.g.,
94 // this appears to be ill-formed:
97 // template <typename T> struct S {
102 // void f(N::S<int>* s) {
103 // s->N::S<int>::~S();
106 // See also PR6358 and PR6359.
107 // For this reason, we're currently only doing the C++03 version of this
108 // code; the C++0x version has to wait until we get a proper spec.
110 DeclContext *LookupCtx = nullptr;
111 bool isDependent = false;
112 bool LookInScope = false;
114 // If we have an object type, it's because we are in a
115 // pseudo-destructor-expression or a member access expression, and
116 // we know what type we're looking for.
118 SearchType = GetTypeFromParser(ObjectTypePtr);
121 NestedNameSpecifier *NNS = SS.getScopeRep();
123 bool AlreadySearched = false;
124 bool LookAtPrefix = true;
125 // C++11 [basic.lookup.qual]p6:
126 // If a pseudo-destructor-name (5.2.4) contains a nested-name-specifier,
127 // the type-names are looked up as types in the scope designated by the
128 // nested-name-specifier. Similarly, in a qualified-id of the form:
130 // nested-name-specifier[opt] class-name :: ~ class-name
132 // the second class-name is looked up in the same scope as the first.
134 // Here, we determine whether the code below is permitted to look at the
135 // prefix of the nested-name-specifier.
136 DeclContext *DC = computeDeclContext(SS, EnteringContext);
137 if (DC && DC->isFileContext()) {
138 AlreadySearched = true;
141 } else if (DC && isa<CXXRecordDecl>(DC)) {
142 LookAtPrefix = false;
146 // The second case from the C++03 rules quoted further above.
147 NestedNameSpecifier *Prefix = nullptr;
148 if (AlreadySearched) {
149 // Nothing left to do.
150 } else if (LookAtPrefix && (Prefix = NNS->getPrefix())) {
151 CXXScopeSpec PrefixSS;
152 PrefixSS.Adopt(NestedNameSpecifierLoc(Prefix, SS.location_data()));
153 LookupCtx = computeDeclContext(PrefixSS, EnteringContext);
154 isDependent = isDependentScopeSpecifier(PrefixSS);
155 } else if (ObjectTypePtr) {
156 LookupCtx = computeDeclContext(SearchType);
157 isDependent = SearchType->isDependentType();
159 LookupCtx = computeDeclContext(SS, EnteringContext);
160 isDependent = LookupCtx && LookupCtx->isDependentContext();
162 } else if (ObjectTypePtr) {
163 // C++ [basic.lookup.classref]p3:
164 // If the unqualified-id is ~type-name, the type-name is looked up
165 // in the context of the entire postfix-expression. If the type T
166 // of the object expression is of a class type C, the type-name is
167 // also looked up in the scope of class C. At least one of the
168 // lookups shall find a name that refers to (possibly
170 LookupCtx = computeDeclContext(SearchType);
171 isDependent = SearchType->isDependentType();
172 assert((isDependent || !SearchType->isIncompleteType()) &&
173 "Caller should have completed object type");
177 // Perform lookup into the current scope (only).
181 TypeDecl *NonMatchingTypeDecl = nullptr;
182 LookupResult Found(*this, &II, NameLoc, LookupOrdinaryName);
183 for (unsigned Step = 0; Step != 2; ++Step) {
184 // Look for the name first in the computed lookup context (if we
185 // have one) and, if that fails to find a match, in the scope (if
186 // we're allowed to look there).
188 if (Step == 0 && LookupCtx)
189 LookupQualifiedName(Found, LookupCtx);
190 else if (Step == 1 && LookInScope && S)
191 LookupName(Found, S);
195 // FIXME: Should we be suppressing ambiguities here?
196 if (Found.isAmbiguous())
199 if (TypeDecl *Type = Found.getAsSingle<TypeDecl>()) {
200 QualType T = Context.getTypeDeclType(Type);
202 if (SearchType.isNull() || SearchType->isDependentType() ||
203 Context.hasSameUnqualifiedType(T, SearchType)) {
204 // We found our type!
206 return CreateParsedType(T,
207 Context.getTrivialTypeSourceInfo(T, NameLoc));
210 if (!SearchType.isNull())
211 NonMatchingTypeDecl = Type;
214 // If the name that we found is a class template name, and it is
215 // the same name as the template name in the last part of the
216 // nested-name-specifier (if present) or the object type, then
217 // this is the destructor for that class.
218 // FIXME: This is a workaround until we get real drafting for core
219 // issue 399, for which there isn't even an obvious direction.
220 if (ClassTemplateDecl *Template = Found.getAsSingle<ClassTemplateDecl>()) {
221 QualType MemberOfType;
223 if (DeclContext *Ctx = computeDeclContext(SS, EnteringContext)) {
224 // Figure out the type of the context, if it has one.
225 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx))
226 MemberOfType = Context.getTypeDeclType(Record);
229 if (MemberOfType.isNull())
230 MemberOfType = SearchType;
232 if (MemberOfType.isNull())
235 // We're referring into a class template specialization. If the
236 // class template we found is the same as the template being
237 // specialized, we found what we are looking for.
238 if (const RecordType *Record = MemberOfType->getAs<RecordType>()) {
239 if (ClassTemplateSpecializationDecl *Spec
240 = dyn_cast<ClassTemplateSpecializationDecl>(Record->getDecl())) {
241 if (Spec->getSpecializedTemplate()->getCanonicalDecl() ==
242 Template->getCanonicalDecl())
243 return CreateParsedType(
245 Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
251 // We're referring to an unresolved class template
252 // specialization. Determine whether we class template we found
253 // is the same as the template being specialized or, if we don't
254 // know which template is being specialized, that it at least
255 // has the same name.
256 if (const TemplateSpecializationType *SpecType
257 = MemberOfType->getAs<TemplateSpecializationType>()) {
258 TemplateName SpecName = SpecType->getTemplateName();
260 // The class template we found is the same template being
262 if (TemplateDecl *SpecTemplate = SpecName.getAsTemplateDecl()) {
263 if (SpecTemplate->getCanonicalDecl() == Template->getCanonicalDecl())
264 return CreateParsedType(
266 Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
271 // The class template we found has the same name as the
272 // (dependent) template name being specialized.
273 if (DependentTemplateName *DepTemplate
274 = SpecName.getAsDependentTemplateName()) {
275 if (DepTemplate->isIdentifier() &&
276 DepTemplate->getIdentifier() == Template->getIdentifier())
277 return CreateParsedType(
279 Context.getTrivialTypeSourceInfo(MemberOfType, NameLoc));
288 // We didn't find our type, but that's okay: it's dependent
291 // FIXME: What if we have no nested-name-specifier?
292 QualType T = CheckTypenameType(ETK_None, SourceLocation(),
293 SS.getWithLocInContext(Context),
295 return ParsedType::make(T);
298 if (NonMatchingTypeDecl) {
299 QualType T = Context.getTypeDeclType(NonMatchingTypeDecl);
300 Diag(NameLoc, diag::err_destructor_expr_type_mismatch)
302 Diag(NonMatchingTypeDecl->getLocation(), diag::note_destructor_type_here)
304 } else if (ObjectTypePtr)
305 Diag(NameLoc, diag::err_ident_in_dtor_not_a_type)
308 SemaDiagnosticBuilder DtorDiag = Diag(NameLoc,
309 diag::err_destructor_class_name);
311 const DeclContext *Ctx = S->getEntity();
312 if (const CXXRecordDecl *Class = dyn_cast_or_null<CXXRecordDecl>(Ctx))
313 DtorDiag << FixItHint::CreateReplacement(SourceRange(NameLoc),
314 Class->getNameAsString());
321 ParsedType Sema::getDestructorType(const DeclSpec& DS, ParsedType ObjectType) {
322 if (DS.getTypeSpecType() == DeclSpec::TST_error || !ObjectType)
324 assert(DS.getTypeSpecType() == DeclSpec::TST_decltype
325 && "only get destructor types from declspecs");
326 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
327 QualType SearchType = GetTypeFromParser(ObjectType);
328 if (SearchType->isDependentType() || Context.hasSameUnqualifiedType(SearchType, T)) {
329 return ParsedType::make(T);
332 Diag(DS.getTypeSpecTypeLoc(), diag::err_destructor_expr_type_mismatch)
337 bool Sema::checkLiteralOperatorId(const CXXScopeSpec &SS,
338 const UnqualifiedId &Name) {
339 assert(Name.getKind() == UnqualifiedId::IK_LiteralOperatorId);
344 switch (SS.getScopeRep()->getKind()) {
345 case NestedNameSpecifier::Identifier:
346 case NestedNameSpecifier::TypeSpec:
347 case NestedNameSpecifier::TypeSpecWithTemplate:
348 // Per C++11 [over.literal]p2, literal operators can only be declared at
349 // namespace scope. Therefore, this unqualified-id cannot name anything.
350 // Reject it early, because we have no AST representation for this in the
351 // case where the scope is dependent.
352 Diag(Name.getLocStart(), diag::err_literal_operator_id_outside_namespace)
356 case NestedNameSpecifier::Global:
357 case NestedNameSpecifier::Namespace:
358 case NestedNameSpecifier::NamespaceAlias:
362 llvm_unreachable("unknown nested name specifier kind");
365 /// \brief Build a C++ typeid expression with a type operand.
366 ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
367 SourceLocation TypeidLoc,
368 TypeSourceInfo *Operand,
369 SourceLocation RParenLoc) {
370 // C++ [expr.typeid]p4:
371 // The top-level cv-qualifiers of the lvalue expression or the type-id
372 // that is the operand of typeid are always ignored.
373 // If the type of the type-id is a class type or a reference to a class
374 // type, the class shall be completely-defined.
377 = Context.getUnqualifiedArrayType(Operand->getType().getNonReferenceType(),
379 if (T->getAs<RecordType>() &&
380 RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
383 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), Operand,
384 SourceRange(TypeidLoc, RParenLoc));
387 /// \brief Build a C++ typeid expression with an expression operand.
388 ExprResult Sema::BuildCXXTypeId(QualType TypeInfoType,
389 SourceLocation TypeidLoc,
391 SourceLocation RParenLoc) {
392 if (E && !E->isTypeDependent()) {
393 if (E->getType()->isPlaceholderType()) {
394 ExprResult result = CheckPlaceholderExpr(E);
395 if (result.isInvalid()) return ExprError();
399 QualType T = E->getType();
400 if (const RecordType *RecordT = T->getAs<RecordType>()) {
401 CXXRecordDecl *RecordD = cast<CXXRecordDecl>(RecordT->getDecl());
402 // C++ [expr.typeid]p3:
403 // [...] If the type of the expression is a class type, the class
404 // shall be completely-defined.
405 if (RequireCompleteType(TypeidLoc, T, diag::err_incomplete_typeid))
408 // C++ [expr.typeid]p3:
409 // When typeid is applied to an expression other than an glvalue of a
410 // polymorphic class type [...] [the] expression is an unevaluated
412 if (RecordD->isPolymorphic() && E->isGLValue()) {
413 // The subexpression is potentially evaluated; switch the context
414 // and recheck the subexpression.
415 ExprResult Result = TransformToPotentiallyEvaluated(E);
416 if (Result.isInvalid()) return ExprError();
419 // We require a vtable to query the type at run time.
420 MarkVTableUsed(TypeidLoc, RecordD);
424 // C++ [expr.typeid]p4:
425 // [...] If the type of the type-id is a reference to a possibly
426 // cv-qualified type, the result of the typeid expression refers to a
427 // std::type_info object representing the cv-unqualified referenced
430 QualType UnqualT = Context.getUnqualifiedArrayType(T, Quals);
431 if (!Context.hasSameType(T, UnqualT)) {
433 E = ImpCastExprToType(E, UnqualT, CK_NoOp, E->getValueKind()).get();
437 return new (Context) CXXTypeidExpr(TypeInfoType.withConst(), E,
438 SourceRange(TypeidLoc, RParenLoc));
441 /// ActOnCXXTypeidOfType - Parse typeid( type-id ) or typeid (expression);
443 Sema::ActOnCXXTypeid(SourceLocation OpLoc, SourceLocation LParenLoc,
444 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
445 // Find the std::type_info type.
446 if (!getStdNamespace())
447 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
449 if (!CXXTypeInfoDecl) {
450 IdentifierInfo *TypeInfoII = &PP.getIdentifierTable().get("type_info");
451 LookupResult R(*this, TypeInfoII, SourceLocation(), LookupTagName);
452 LookupQualifiedName(R, getStdNamespace());
453 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
454 // Microsoft's typeinfo doesn't have type_info in std but in the global
455 // namespace if _HAS_EXCEPTIONS is defined to 0. See PR13153.
456 if (!CXXTypeInfoDecl && LangOpts.MSVCCompat) {
457 LookupQualifiedName(R, Context.getTranslationUnitDecl());
458 CXXTypeInfoDecl = R.getAsSingle<RecordDecl>();
460 if (!CXXTypeInfoDecl)
461 return ExprError(Diag(OpLoc, diag::err_need_header_before_typeid));
464 if (!getLangOpts().RTTI) {
465 return ExprError(Diag(OpLoc, diag::err_no_typeid_with_fno_rtti));
468 QualType TypeInfoType = Context.getTypeDeclType(CXXTypeInfoDecl);
471 // The operand is a type; handle it as such.
472 TypeSourceInfo *TInfo = nullptr;
473 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
479 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
481 return BuildCXXTypeId(TypeInfoType, OpLoc, TInfo, RParenLoc);
484 // The operand is an expression.
485 return BuildCXXTypeId(TypeInfoType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
488 /// \brief Build a Microsoft __uuidof expression with a type operand.
489 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType,
490 SourceLocation TypeidLoc,
491 TypeSourceInfo *Operand,
492 SourceLocation RParenLoc) {
493 if (!Operand->getType()->isDependentType()) {
494 bool HasMultipleGUIDs = false;
495 if (!CXXUuidofExpr::GetUuidAttrOfType(Operand->getType(),
496 &HasMultipleGUIDs)) {
497 if (HasMultipleGUIDs)
498 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
500 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
504 return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), Operand,
505 SourceRange(TypeidLoc, RParenLoc));
508 /// \brief Build a Microsoft __uuidof expression with an expression operand.
509 ExprResult Sema::BuildCXXUuidof(QualType TypeInfoType,
510 SourceLocation TypeidLoc,
512 SourceLocation RParenLoc) {
513 if (!E->getType()->isDependentType()) {
514 bool HasMultipleGUIDs = false;
515 if (!CXXUuidofExpr::GetUuidAttrOfType(E->getType(), &HasMultipleGUIDs) &&
516 !E->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
517 if (HasMultipleGUIDs)
518 return ExprError(Diag(TypeidLoc, diag::err_uuidof_with_multiple_guids));
520 return ExprError(Diag(TypeidLoc, diag::err_uuidof_without_guid));
524 return new (Context) CXXUuidofExpr(TypeInfoType.withConst(), E,
525 SourceRange(TypeidLoc, RParenLoc));
528 /// ActOnCXXUuidof - Parse __uuidof( type-id ) or __uuidof (expression);
530 Sema::ActOnCXXUuidof(SourceLocation OpLoc, SourceLocation LParenLoc,
531 bool isType, void *TyOrExpr, SourceLocation RParenLoc) {
532 // If MSVCGuidDecl has not been cached, do the lookup.
534 IdentifierInfo *GuidII = &PP.getIdentifierTable().get("_GUID");
535 LookupResult R(*this, GuidII, SourceLocation(), LookupTagName);
536 LookupQualifiedName(R, Context.getTranslationUnitDecl());
537 MSVCGuidDecl = R.getAsSingle<RecordDecl>();
539 return ExprError(Diag(OpLoc, diag::err_need_header_before_ms_uuidof));
542 QualType GuidType = Context.getTypeDeclType(MSVCGuidDecl);
545 // The operand is a type; handle it as such.
546 TypeSourceInfo *TInfo = nullptr;
547 QualType T = GetTypeFromParser(ParsedType::getFromOpaquePtr(TyOrExpr),
553 TInfo = Context.getTrivialTypeSourceInfo(T, OpLoc);
555 return BuildCXXUuidof(GuidType, OpLoc, TInfo, RParenLoc);
558 // The operand is an expression.
559 return BuildCXXUuidof(GuidType, OpLoc, (Expr*)TyOrExpr, RParenLoc);
562 /// ActOnCXXBoolLiteral - Parse {true,false} literals.
564 Sema::ActOnCXXBoolLiteral(SourceLocation OpLoc, tok::TokenKind Kind) {
565 assert((Kind == tok::kw_true || Kind == tok::kw_false) &&
566 "Unknown C++ Boolean value!");
568 CXXBoolLiteralExpr(Kind == tok::kw_true, Context.BoolTy, OpLoc);
571 /// ActOnCXXNullPtrLiteral - Parse 'nullptr'.
573 Sema::ActOnCXXNullPtrLiteral(SourceLocation Loc) {
574 return new (Context) CXXNullPtrLiteralExpr(Context.NullPtrTy, Loc);
577 /// ActOnCXXThrow - Parse throw expressions.
579 Sema::ActOnCXXThrow(Scope *S, SourceLocation OpLoc, Expr *Ex) {
580 bool IsThrownVarInScope = false;
582 // C++0x [class.copymove]p31:
583 // When certain criteria are met, an implementation is allowed to omit the
584 // copy/move construction of a class object [...]
586 // - in a throw-expression, when the operand is the name of a
587 // non-volatile automatic object (other than a function or catch-
588 // clause parameter) whose scope does not extend beyond the end of the
589 // innermost enclosing try-block (if there is one), the copy/move
590 // operation from the operand to the exception object (15.1) can be
591 // omitted by constructing the automatic object directly into the
593 if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Ex->IgnoreParens()))
594 if (VarDecl *Var = dyn_cast<VarDecl>(DRE->getDecl())) {
595 if (Var->hasLocalStorage() && !Var->getType().isVolatileQualified()) {
596 for( ; S; S = S->getParent()) {
597 if (S->isDeclScope(Var)) {
598 IsThrownVarInScope = true;
603 (Scope::FnScope | Scope::ClassScope | Scope::BlockScope |
604 Scope::FunctionPrototypeScope | Scope::ObjCMethodScope |
612 return BuildCXXThrow(OpLoc, Ex, IsThrownVarInScope);
615 ExprResult Sema::BuildCXXThrow(SourceLocation OpLoc, Expr *Ex,
616 bool IsThrownVarInScope) {
617 // Don't report an error if 'throw' is used in system headers.
618 if (!getLangOpts().CXXExceptions &&
619 !getSourceManager().isInSystemHeader(OpLoc))
620 Diag(OpLoc, diag::err_exceptions_disabled) << "throw";
622 if (getCurScope() && getCurScope()->isOpenMPSimdDirectiveScope())
623 Diag(OpLoc, diag::err_omp_simd_region_cannot_use_stmt) << "throw";
625 if (Ex && !Ex->isTypeDependent()) {
626 ExprResult ExRes = CheckCXXThrowOperand(OpLoc, Ex, IsThrownVarInScope);
627 if (ExRes.isInvalid())
633 CXXThrowExpr(Ex, Context.VoidTy, OpLoc, IsThrownVarInScope);
636 /// CheckCXXThrowOperand - Validate the operand of a throw.
637 ExprResult Sema::CheckCXXThrowOperand(SourceLocation ThrowLoc, Expr *E,
638 bool IsThrownVarInScope) {
639 // C++ [except.throw]p3:
640 // A throw-expression initializes a temporary object, called the exception
641 // object, the type of which is determined by removing any top-level
642 // cv-qualifiers from the static type of the operand of throw and adjusting
643 // the type from "array of T" or "function returning T" to "pointer to T"
644 // or "pointer to function returning T", [...]
645 if (E->getType().hasQualifiers())
646 E = ImpCastExprToType(E, E->getType().getUnqualifiedType(), CK_NoOp,
647 E->getValueKind()).get();
649 ExprResult Res = DefaultFunctionArrayConversion(E);
654 // If the type of the exception would be an incomplete type or a pointer
655 // to an incomplete type other than (cv) void the program is ill-formed.
656 QualType Ty = E->getType();
657 bool isPointer = false;
658 if (const PointerType* Ptr = Ty->getAs<PointerType>()) {
659 Ty = Ptr->getPointeeType();
662 if (!isPointer || !Ty->isVoidType()) {
663 if (RequireCompleteType(ThrowLoc, Ty,
664 isPointer? diag::err_throw_incomplete_ptr
665 : diag::err_throw_incomplete,
666 E->getSourceRange()))
669 if (RequireNonAbstractType(ThrowLoc, E->getType(),
670 diag::err_throw_abstract_type, E))
674 // Initialize the exception result. This implicitly weeds out
675 // abstract types or types with inaccessible copy constructors.
677 // C++0x [class.copymove]p31:
678 // When certain criteria are met, an implementation is allowed to omit the
679 // copy/move construction of a class object [...]
681 // - in a throw-expression, when the operand is the name of a
682 // non-volatile automatic object (other than a function or catch-clause
683 // parameter) whose scope does not extend beyond the end of the
684 // innermost enclosing try-block (if there is one), the copy/move
685 // operation from the operand to the exception object (15.1) can be
686 // omitted by constructing the automatic object directly into the
688 const VarDecl *NRVOVariable = nullptr;
689 if (IsThrownVarInScope)
690 NRVOVariable = getCopyElisionCandidate(QualType(), E, false);
692 InitializedEntity Entity =
693 InitializedEntity::InitializeException(ThrowLoc, E->getType(),
694 /*NRVO=*/NRVOVariable != nullptr);
695 Res = PerformMoveOrCopyInitialization(Entity, NRVOVariable,
702 // If the exception has class type, we need additional handling.
703 const RecordType *RecordTy = Ty->getAs<RecordType>();
706 CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl());
708 // If we are throwing a polymorphic class type or pointer thereof,
709 // exception handling will make use of the vtable.
710 MarkVTableUsed(ThrowLoc, RD);
712 // If a pointer is thrown, the referenced object will not be destroyed.
716 // If the class has a destructor, we must be able to call it.
717 if (RD->hasIrrelevantDestructor())
720 CXXDestructorDecl *Destructor = LookupDestructor(RD);
724 MarkFunctionReferenced(E->getExprLoc(), Destructor);
725 CheckDestructorAccess(E->getExprLoc(), Destructor,
726 PDiag(diag::err_access_dtor_exception) << Ty);
727 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
732 QualType Sema::getCurrentThisType() {
733 DeclContext *DC = getFunctionLevelDeclContext();
734 QualType ThisTy = CXXThisTypeOverride;
735 if (CXXMethodDecl *method = dyn_cast<CXXMethodDecl>(DC)) {
736 if (method && method->isInstance())
737 ThisTy = method->getThisType(Context);
739 if (ThisTy.isNull()) {
740 if (isGenericLambdaCallOperatorSpecialization(CurContext) &&
741 CurContext->getParent()->getParent()->isRecord()) {
742 // This is a generic lambda call operator that is being instantiated
743 // within a default initializer - so use the enclosing class as 'this'.
744 // There is no enclosing member function to retrieve the 'this' pointer
746 QualType ClassTy = Context.getTypeDeclType(
747 cast<CXXRecordDecl>(CurContext->getParent()->getParent()));
748 // There are no cv-qualifiers for 'this' within default initializers,
749 // per [expr.prim.general]p4.
750 return Context.getPointerType(ClassTy);
756 Sema::CXXThisScopeRAII::CXXThisScopeRAII(Sema &S,
758 unsigned CXXThisTypeQuals,
760 : S(S), OldCXXThisTypeOverride(S.CXXThisTypeOverride), Enabled(false)
762 if (!Enabled || !ContextDecl)
765 CXXRecordDecl *Record = nullptr;
766 if (ClassTemplateDecl *Template = dyn_cast<ClassTemplateDecl>(ContextDecl))
767 Record = Template->getTemplatedDecl();
769 Record = cast<CXXRecordDecl>(ContextDecl);
771 S.CXXThisTypeOverride
772 = S.Context.getPointerType(
773 S.Context.getRecordType(Record).withCVRQualifiers(CXXThisTypeQuals));
775 this->Enabled = true;
779 Sema::CXXThisScopeRAII::~CXXThisScopeRAII() {
781 S.CXXThisTypeOverride = OldCXXThisTypeOverride;
785 static Expr *captureThis(ASTContext &Context, RecordDecl *RD,
786 QualType ThisTy, SourceLocation Loc) {
788 = FieldDecl::Create(Context, RD, Loc, Loc, nullptr, ThisTy,
789 Context.getTrivialTypeSourceInfo(ThisTy, Loc),
790 nullptr, false, ICIS_NoInit);
791 Field->setImplicit(true);
792 Field->setAccess(AS_private);
794 return new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit*/true);
797 bool Sema::CheckCXXThisCapture(SourceLocation Loc, bool Explicit,
798 bool BuildAndDiagnose, const unsigned *const FunctionScopeIndexToStopAt) {
799 // We don't need to capture this in an unevaluated context.
800 if (isUnevaluatedContext() && !Explicit)
803 const unsigned MaxFunctionScopesIndex = FunctionScopeIndexToStopAt ?
804 *FunctionScopeIndexToStopAt : FunctionScopes.size() - 1;
805 // Otherwise, check that we can capture 'this'.
806 unsigned NumClosures = 0;
807 for (unsigned idx = MaxFunctionScopesIndex; idx != 0; idx--) {
808 if (CapturingScopeInfo *CSI =
809 dyn_cast<CapturingScopeInfo>(FunctionScopes[idx])) {
810 if (CSI->CXXThisCaptureIndex != 0) {
811 // 'this' is already being captured; there isn't anything more to do.
814 LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI);
815 if (LSI && isGenericLambdaCallOperatorSpecialization(LSI->CallOperator)) {
816 // This context can't implicitly capture 'this'; fail out.
817 if (BuildAndDiagnose)
818 Diag(Loc, diag::err_this_capture) << Explicit;
821 if (CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByref ||
822 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_LambdaByval ||
823 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_Block ||
824 CSI->ImpCaptureStyle == CapturingScopeInfo::ImpCap_CapturedRegion ||
826 // This closure can capture 'this'; continue looking upwards.
831 // This context can't implicitly capture 'this'; fail out.
832 if (BuildAndDiagnose)
833 Diag(Loc, diag::err_this_capture) << Explicit;
838 if (!BuildAndDiagnose) return false;
839 // Mark that we're implicitly capturing 'this' in all the scopes we skipped.
840 // FIXME: We need to delay this marking in PotentiallyPotentiallyEvaluated
842 for (unsigned idx = MaxFunctionScopesIndex; NumClosures;
843 --idx, --NumClosures) {
844 CapturingScopeInfo *CSI = cast<CapturingScopeInfo>(FunctionScopes[idx]);
845 Expr *ThisExpr = nullptr;
846 QualType ThisTy = getCurrentThisType();
847 if (LambdaScopeInfo *LSI = dyn_cast<LambdaScopeInfo>(CSI))
848 // For lambda expressions, build a field and an initializing expression.
849 ThisExpr = captureThis(Context, LSI->Lambda, ThisTy, Loc);
850 else if (CapturedRegionScopeInfo *RSI
851 = dyn_cast<CapturedRegionScopeInfo>(FunctionScopes[idx]))
852 ThisExpr = captureThis(Context, RSI->TheRecordDecl, ThisTy, Loc);
854 bool isNested = NumClosures > 1;
855 CSI->addThisCapture(isNested, Loc, ThisTy, ThisExpr);
860 ExprResult Sema::ActOnCXXThis(SourceLocation Loc) {
861 /// C++ 9.3.2: In the body of a non-static member function, the keyword this
862 /// is a non-lvalue expression whose value is the address of the object for
863 /// which the function is called.
865 QualType ThisTy = getCurrentThisType();
866 if (ThisTy.isNull()) return Diag(Loc, diag::err_invalid_this_use);
868 CheckCXXThisCapture(Loc);
869 return new (Context) CXXThisExpr(Loc, ThisTy, /*isImplicit=*/false);
872 bool Sema::isThisOutsideMemberFunctionBody(QualType BaseType) {
873 // If we're outside the body of a member function, then we'll have a specified
875 if (CXXThisTypeOverride.isNull())
878 // Determine whether we're looking into a class that's currently being
880 CXXRecordDecl *Class = BaseType->getAsCXXRecordDecl();
881 return Class && Class->isBeingDefined();
885 Sema::ActOnCXXTypeConstructExpr(ParsedType TypeRep,
886 SourceLocation LParenLoc,
888 SourceLocation RParenLoc) {
892 TypeSourceInfo *TInfo;
893 QualType Ty = GetTypeFromParser(TypeRep, &TInfo);
895 TInfo = Context.getTrivialTypeSourceInfo(Ty, SourceLocation());
897 return BuildCXXTypeConstructExpr(TInfo, LParenLoc, exprs, RParenLoc);
900 /// ActOnCXXTypeConstructExpr - Parse construction of a specified type.
901 /// Can be interpreted either as function-style casting ("int(x)")
902 /// or class type construction ("ClassType(x,y,z)")
903 /// or creation of a value-initialized type ("int()").
905 Sema::BuildCXXTypeConstructExpr(TypeSourceInfo *TInfo,
906 SourceLocation LParenLoc,
908 SourceLocation RParenLoc) {
909 QualType Ty = TInfo->getType();
910 SourceLocation TyBeginLoc = TInfo->getTypeLoc().getBeginLoc();
912 if (Ty->isDependentType() || CallExpr::hasAnyTypeDependentArguments(Exprs)) {
913 return CXXUnresolvedConstructExpr::Create(Context, TInfo, LParenLoc, Exprs,
917 bool ListInitialization = LParenLoc.isInvalid();
918 assert((!ListInitialization || (Exprs.size() == 1 && isa<InitListExpr>(Exprs[0])))
919 && "List initialization must have initializer list as expression.");
920 SourceRange FullRange = SourceRange(TyBeginLoc,
921 ListInitialization ? Exprs[0]->getSourceRange().getEnd() : RParenLoc);
923 // C++ [expr.type.conv]p1:
924 // If the expression list is a single expression, the type conversion
925 // expression is equivalent (in definedness, and if defined in meaning) to the
926 // corresponding cast expression.
927 if (Exprs.size() == 1 && !ListInitialization) {
928 Expr *Arg = Exprs[0];
929 return BuildCXXFunctionalCastExpr(TInfo, LParenLoc, Arg, RParenLoc);
932 QualType ElemTy = Ty;
933 if (Ty->isArrayType()) {
934 if (!ListInitialization)
935 return ExprError(Diag(TyBeginLoc,
936 diag::err_value_init_for_array_type) << FullRange);
937 ElemTy = Context.getBaseElementType(Ty);
940 if (!Ty->isVoidType() &&
941 RequireCompleteType(TyBeginLoc, ElemTy,
942 diag::err_invalid_incomplete_type_use, FullRange))
945 if (RequireNonAbstractType(TyBeginLoc, Ty,
946 diag::err_allocation_of_abstract_type))
949 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TInfo);
950 InitializationKind Kind =
951 Exprs.size() ? ListInitialization
952 ? InitializationKind::CreateDirectList(TyBeginLoc)
953 : InitializationKind::CreateDirect(TyBeginLoc, LParenLoc, RParenLoc)
954 : InitializationKind::CreateValue(TyBeginLoc, LParenLoc, RParenLoc);
955 InitializationSequence InitSeq(*this, Entity, Kind, Exprs);
956 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Exprs);
958 if (Result.isInvalid() || !ListInitialization)
961 Expr *Inner = Result.get();
962 if (CXXBindTemporaryExpr *BTE = dyn_cast_or_null<CXXBindTemporaryExpr>(Inner))
963 Inner = BTE->getSubExpr();
964 if (isa<InitListExpr>(Inner)) {
965 // If the list-initialization doesn't involve a constructor call, we'll get
966 // the initializer-list (with corrected type) back, but that's not what we
967 // want, since it will be treated as an initializer list in further
968 // processing. Explicitly insert a cast here.
969 QualType ResultType = Result.get()->getType();
970 Result = CXXFunctionalCastExpr::Create(
971 Context, ResultType, Expr::getValueKindForType(TInfo->getType()), TInfo,
972 CK_NoOp, Result.get(), /*Path=*/nullptr, LParenLoc, RParenLoc);
975 // FIXME: Improve AST representation?
979 /// doesUsualArrayDeleteWantSize - Answers whether the usual
980 /// operator delete[] for the given type has a size_t parameter.
981 static bool doesUsualArrayDeleteWantSize(Sema &S, SourceLocation loc,
982 QualType allocType) {
983 const RecordType *record =
984 allocType->getBaseElementTypeUnsafe()->getAs<RecordType>();
985 if (!record) return false;
987 // Try to find an operator delete[] in class scope.
989 DeclarationName deleteName =
990 S.Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete);
991 LookupResult ops(S, deleteName, loc, Sema::LookupOrdinaryName);
992 S.LookupQualifiedName(ops, record->getDecl());
994 // We're just doing this for information.
995 ops.suppressDiagnostics();
997 // Very likely: there's no operator delete[].
998 if (ops.empty()) return false;
1000 // If it's ambiguous, it should be illegal to call operator delete[]
1001 // on this thing, so it doesn't matter if we allocate extra space or not.
1002 if (ops.isAmbiguous()) return false;
1004 LookupResult::Filter filter = ops.makeFilter();
1005 while (filter.hasNext()) {
1006 NamedDecl *del = filter.next()->getUnderlyingDecl();
1008 // C++0x [basic.stc.dynamic.deallocation]p2:
1009 // A template instance is never a usual deallocation function,
1010 // regardless of its signature.
1011 if (isa<FunctionTemplateDecl>(del)) {
1016 // C++0x [basic.stc.dynamic.deallocation]p2:
1017 // If class T does not declare [an operator delete[] with one
1018 // parameter] but does declare a member deallocation function
1019 // named operator delete[] with exactly two parameters, the
1020 // second of which has type std::size_t, then this function
1021 // is a usual deallocation function.
1022 if (!cast<CXXMethodDecl>(del)->isUsualDeallocationFunction()) {
1029 if (!ops.isSingleResult()) return false;
1031 const FunctionDecl *del = cast<FunctionDecl>(ops.getFoundDecl());
1032 return (del->getNumParams() == 2);
1035 /// \brief Parsed a C++ 'new' expression (C++ 5.3.4).
1038 /// @code new (memory) int[size][4] @endcode
1040 /// @code ::new Foo(23, "hello") @endcode
1042 /// \param StartLoc The first location of the expression.
1043 /// \param UseGlobal True if 'new' was prefixed with '::'.
1044 /// \param PlacementLParen Opening paren of the placement arguments.
1045 /// \param PlacementArgs Placement new arguments.
1046 /// \param PlacementRParen Closing paren of the placement arguments.
1047 /// \param TypeIdParens If the type is in parens, the source range.
1048 /// \param D The type to be allocated, as well as array dimensions.
1049 /// \param Initializer The initializing expression or initializer-list, or null
1050 /// if there is none.
1052 Sema::ActOnCXXNew(SourceLocation StartLoc, bool UseGlobal,
1053 SourceLocation PlacementLParen, MultiExprArg PlacementArgs,
1054 SourceLocation PlacementRParen, SourceRange TypeIdParens,
1055 Declarator &D, Expr *Initializer) {
1056 bool TypeContainsAuto = D.getDeclSpec().containsPlaceholderType();
1058 Expr *ArraySize = nullptr;
1059 // If the specified type is an array, unwrap it and save the expression.
1060 if (D.getNumTypeObjects() > 0 &&
1061 D.getTypeObject(0).Kind == DeclaratorChunk::Array) {
1062 DeclaratorChunk &Chunk = D.getTypeObject(0);
1063 if (TypeContainsAuto)
1064 return ExprError(Diag(Chunk.Loc, diag::err_new_array_of_auto)
1065 << D.getSourceRange());
1066 if (Chunk.Arr.hasStatic)
1067 return ExprError(Diag(Chunk.Loc, diag::err_static_illegal_in_new)
1068 << D.getSourceRange());
1069 if (!Chunk.Arr.NumElts)
1070 return ExprError(Diag(Chunk.Loc, diag::err_array_new_needs_size)
1071 << D.getSourceRange());
1073 ArraySize = static_cast<Expr*>(Chunk.Arr.NumElts);
1074 D.DropFirstTypeObject();
1077 // Every dimension shall be of constant size.
1079 for (unsigned I = 0, N = D.getNumTypeObjects(); I < N; ++I) {
1080 if (D.getTypeObject(I).Kind != DeclaratorChunk::Array)
1083 DeclaratorChunk::ArrayTypeInfo &Array = D.getTypeObject(I).Arr;
1084 if (Expr *NumElts = (Expr *)Array.NumElts) {
1085 if (!NumElts->isTypeDependent() && !NumElts->isValueDependent()) {
1086 if (getLangOpts().CPlusPlus1y) {
1087 // C++1y [expr.new]p6: Every constant-expression in a noptr-new-declarator
1088 // shall be a converted constant expression (5.19) of type std::size_t
1089 // and shall evaluate to a strictly positive value.
1090 unsigned IntWidth = Context.getTargetInfo().getIntWidth();
1091 assert(IntWidth && "Builtin type of size 0?");
1092 llvm::APSInt Value(IntWidth);
1094 = CheckConvertedConstantExpression(NumElts, Context.getSizeType(), Value,
1099 = VerifyIntegerConstantExpression(NumElts, nullptr,
1100 diag::err_new_array_nonconst)
1110 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, /*Scope=*/nullptr);
1111 QualType AllocType = TInfo->getType();
1112 if (D.isInvalidType())
1115 SourceRange DirectInitRange;
1116 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer))
1117 DirectInitRange = List->getSourceRange();
1119 return BuildCXXNew(SourceRange(StartLoc, D.getLocEnd()), UseGlobal,
1132 static bool isLegalArrayNewInitializer(CXXNewExpr::InitializationStyle Style,
1136 if (ParenListExpr *PLE = dyn_cast<ParenListExpr>(Init))
1137 return PLE->getNumExprs() == 0;
1138 if (isa<ImplicitValueInitExpr>(Init))
1140 else if (CXXConstructExpr *CCE = dyn_cast<CXXConstructExpr>(Init))
1141 return !CCE->isListInitialization() &&
1142 CCE->getConstructor()->isDefaultConstructor();
1143 else if (Style == CXXNewExpr::ListInit) {
1144 assert(isa<InitListExpr>(Init) &&
1145 "Shouldn't create list CXXConstructExprs for arrays.");
1152 Sema::BuildCXXNew(SourceRange Range, bool UseGlobal,
1153 SourceLocation PlacementLParen,
1154 MultiExprArg PlacementArgs,
1155 SourceLocation PlacementRParen,
1156 SourceRange TypeIdParens,
1158 TypeSourceInfo *AllocTypeInfo,
1160 SourceRange DirectInitRange,
1162 bool TypeMayContainAuto) {
1163 SourceRange TypeRange = AllocTypeInfo->getTypeLoc().getSourceRange();
1164 SourceLocation StartLoc = Range.getBegin();
1166 CXXNewExpr::InitializationStyle initStyle;
1167 if (DirectInitRange.isValid()) {
1168 assert(Initializer && "Have parens but no initializer.");
1169 initStyle = CXXNewExpr::CallInit;
1170 } else if (Initializer && isa<InitListExpr>(Initializer))
1171 initStyle = CXXNewExpr::ListInit;
1173 assert((!Initializer || isa<ImplicitValueInitExpr>(Initializer) ||
1174 isa<CXXConstructExpr>(Initializer)) &&
1175 "Initializer expression that cannot have been implicitly created.");
1176 initStyle = CXXNewExpr::NoInit;
1179 Expr **Inits = &Initializer;
1180 unsigned NumInits = Initializer ? 1 : 0;
1181 if (ParenListExpr *List = dyn_cast_or_null<ParenListExpr>(Initializer)) {
1182 assert(initStyle == CXXNewExpr::CallInit && "paren init for non-call init");
1183 Inits = List->getExprs();
1184 NumInits = List->getNumExprs();
1187 // C++11 [dcl.spec.auto]p6. Deduce the type which 'auto' stands in for.
1188 if (TypeMayContainAuto && AllocType->isUndeducedType()) {
1189 if (initStyle == CXXNewExpr::NoInit || NumInits == 0)
1190 return ExprError(Diag(StartLoc, diag::err_auto_new_requires_ctor_arg)
1191 << AllocType << TypeRange);
1192 if (initStyle == CXXNewExpr::ListInit ||
1193 (NumInits == 1 && isa<InitListExpr>(Inits[0])))
1194 return ExprError(Diag(Inits[0]->getLocStart(),
1195 diag::err_auto_new_list_init)
1196 << AllocType << TypeRange);
1198 Expr *FirstBad = Inits[1];
1199 return ExprError(Diag(FirstBad->getLocStart(),
1200 diag::err_auto_new_ctor_multiple_expressions)
1201 << AllocType << TypeRange);
1203 Expr *Deduce = Inits[0];
1204 QualType DeducedType;
1205 if (DeduceAutoType(AllocTypeInfo, Deduce, DeducedType) == DAR_Failed)
1206 return ExprError(Diag(StartLoc, diag::err_auto_new_deduction_failure)
1207 << AllocType << Deduce->getType()
1208 << TypeRange << Deduce->getSourceRange());
1209 if (DeducedType.isNull())
1211 AllocType = DeducedType;
1214 // Per C++0x [expr.new]p5, the type being constructed may be a
1215 // typedef of an array type.
1217 if (const ConstantArrayType *Array
1218 = Context.getAsConstantArrayType(AllocType)) {
1219 ArraySize = IntegerLiteral::Create(Context, Array->getSize(),
1220 Context.getSizeType(),
1221 TypeRange.getEnd());
1222 AllocType = Array->getElementType();
1226 if (CheckAllocatedType(AllocType, TypeRange.getBegin(), TypeRange))
1229 if (initStyle == CXXNewExpr::ListInit &&
1230 isStdInitializerList(AllocType, nullptr)) {
1231 Diag(AllocTypeInfo->getTypeLoc().getBeginLoc(),
1232 diag::warn_dangling_std_initializer_list)
1233 << /*at end of FE*/0 << Inits[0]->getSourceRange();
1236 // In ARC, infer 'retaining' for the allocated
1237 if (getLangOpts().ObjCAutoRefCount &&
1238 AllocType.getObjCLifetime() == Qualifiers::OCL_None &&
1239 AllocType->isObjCLifetimeType()) {
1240 AllocType = Context.getLifetimeQualifiedType(AllocType,
1241 AllocType->getObjCARCImplicitLifetime());
1244 QualType ResultType = Context.getPointerType(AllocType);
1246 if (ArraySize && ArraySize->getType()->isNonOverloadPlaceholderType()) {
1247 ExprResult result = CheckPlaceholderExpr(ArraySize);
1248 if (result.isInvalid()) return ExprError();
1249 ArraySize = result.get();
1251 // C++98 5.3.4p6: "The expression in a direct-new-declarator shall have
1252 // integral or enumeration type with a non-negative value."
1253 // C++11 [expr.new]p6: The expression [...] shall be of integral or unscoped
1254 // enumeration type, or a class type for which a single non-explicit
1255 // conversion function to integral or unscoped enumeration type exists.
1256 // C++1y [expr.new]p6: The expression [...] is implicitly converted to
1258 if (ArraySize && !ArraySize->isTypeDependent()) {
1259 ExprResult ConvertedSize;
1260 if (getLangOpts().CPlusPlus1y) {
1261 assert(Context.getTargetInfo().getIntWidth() && "Builtin type of size 0?");
1263 ConvertedSize = PerformImplicitConversion(ArraySize, Context.getSizeType(),
1266 if (!ConvertedSize.isInvalid() &&
1267 ArraySize->getType()->getAs<RecordType>())
1268 // Diagnose the compatibility of this conversion.
1269 Diag(StartLoc, diag::warn_cxx98_compat_array_size_conversion)
1270 << ArraySize->getType() << 0 << "'size_t'";
1272 class SizeConvertDiagnoser : public ICEConvertDiagnoser {
1277 SizeConvertDiagnoser(Expr *ArraySize)
1278 : ICEConvertDiagnoser(/*AllowScopedEnumerations*/false, false, false),
1279 ArraySize(ArraySize) {}
1281 SemaDiagnosticBuilder diagnoseNotInt(Sema &S, SourceLocation Loc,
1282 QualType T) override {
1283 return S.Diag(Loc, diag::err_array_size_not_integral)
1284 << S.getLangOpts().CPlusPlus11 << T;
1287 SemaDiagnosticBuilder diagnoseIncomplete(
1288 Sema &S, SourceLocation Loc, QualType T) override {
1289 return S.Diag(Loc, diag::err_array_size_incomplete_type)
1290 << T << ArraySize->getSourceRange();
1293 SemaDiagnosticBuilder diagnoseExplicitConv(
1294 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
1295 return S.Diag(Loc, diag::err_array_size_explicit_conversion) << T << ConvTy;
1298 SemaDiagnosticBuilder noteExplicitConv(
1299 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1300 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1301 << ConvTy->isEnumeralType() << ConvTy;
1304 SemaDiagnosticBuilder diagnoseAmbiguous(
1305 Sema &S, SourceLocation Loc, QualType T) override {
1306 return S.Diag(Loc, diag::err_array_size_ambiguous_conversion) << T;
1309 SemaDiagnosticBuilder noteAmbiguous(
1310 Sema &S, CXXConversionDecl *Conv, QualType ConvTy) override {
1311 return S.Diag(Conv->getLocation(), diag::note_array_size_conversion)
1312 << ConvTy->isEnumeralType() << ConvTy;
1315 virtual SemaDiagnosticBuilder diagnoseConversion(
1316 Sema &S, SourceLocation Loc, QualType T, QualType ConvTy) override {
1318 S.getLangOpts().CPlusPlus11
1319 ? diag::warn_cxx98_compat_array_size_conversion
1320 : diag::ext_array_size_conversion)
1321 << T << ConvTy->isEnumeralType() << ConvTy;
1323 } SizeDiagnoser(ArraySize);
1325 ConvertedSize = PerformContextualImplicitConversion(StartLoc, ArraySize,
1328 if (ConvertedSize.isInvalid())
1331 ArraySize = ConvertedSize.get();
1332 QualType SizeType = ArraySize->getType();
1334 if (!SizeType->isIntegralOrUnscopedEnumerationType())
1337 // C++98 [expr.new]p7:
1338 // The expression in a direct-new-declarator shall have integral type
1339 // with a non-negative value.
1341 // Let's see if this is a constant < 0. If so, we reject it out of
1342 // hand. Otherwise, if it's not a constant, we must have an unparenthesized
1345 // Note: such a construct has well-defined semantics in C++11: it throws
1346 // std::bad_array_new_length.
1347 if (!ArraySize->isValueDependent()) {
1349 // We've already performed any required implicit conversion to integer or
1350 // unscoped enumeration type.
1351 if (ArraySize->isIntegerConstantExpr(Value, Context)) {
1352 if (Value < llvm::APSInt(
1353 llvm::APInt::getNullValue(Value.getBitWidth()),
1354 Value.isUnsigned())) {
1355 if (getLangOpts().CPlusPlus11)
1356 Diag(ArraySize->getLocStart(),
1357 diag::warn_typecheck_negative_array_new_size)
1358 << ArraySize->getSourceRange();
1360 return ExprError(Diag(ArraySize->getLocStart(),
1361 diag::err_typecheck_negative_array_size)
1362 << ArraySize->getSourceRange());
1363 } else if (!AllocType->isDependentType()) {
1364 unsigned ActiveSizeBits =
1365 ConstantArrayType::getNumAddressingBits(Context, AllocType, Value);
1366 if (ActiveSizeBits > ConstantArrayType::getMaxSizeBits(Context)) {
1367 if (getLangOpts().CPlusPlus11)
1368 Diag(ArraySize->getLocStart(),
1369 diag::warn_array_new_too_large)
1370 << Value.toString(10)
1371 << ArraySize->getSourceRange();
1373 return ExprError(Diag(ArraySize->getLocStart(),
1374 diag::err_array_too_large)
1375 << Value.toString(10)
1376 << ArraySize->getSourceRange());
1379 } else if (TypeIdParens.isValid()) {
1380 // Can't have dynamic array size when the type-id is in parentheses.
1381 Diag(ArraySize->getLocStart(), diag::ext_new_paren_array_nonconst)
1382 << ArraySize->getSourceRange()
1383 << FixItHint::CreateRemoval(TypeIdParens.getBegin())
1384 << FixItHint::CreateRemoval(TypeIdParens.getEnd());
1386 TypeIdParens = SourceRange();
1390 // Note that we do *not* convert the argument in any way. It can
1391 // be signed, larger than size_t, whatever.
1394 FunctionDecl *OperatorNew = nullptr;
1395 FunctionDecl *OperatorDelete = nullptr;
1397 if (!AllocType->isDependentType() &&
1398 !Expr::hasAnyTypeDependentArguments(PlacementArgs) &&
1399 FindAllocationFunctions(StartLoc,
1400 SourceRange(PlacementLParen, PlacementRParen),
1401 UseGlobal, AllocType, ArraySize, PlacementArgs,
1402 OperatorNew, OperatorDelete))
1405 // If this is an array allocation, compute whether the usual array
1406 // deallocation function for the type has a size_t parameter.
1407 bool UsualArrayDeleteWantsSize = false;
1408 if (ArraySize && !AllocType->isDependentType())
1409 UsualArrayDeleteWantsSize
1410 = doesUsualArrayDeleteWantSize(*this, StartLoc, AllocType);
1412 SmallVector<Expr *, 8> AllPlaceArgs;
1414 const FunctionProtoType *Proto =
1415 OperatorNew->getType()->getAs<FunctionProtoType>();
1416 VariadicCallType CallType = Proto->isVariadic() ? VariadicFunction
1417 : VariadicDoesNotApply;
1419 // We've already converted the placement args, just fill in any default
1420 // arguments. Skip the first parameter because we don't have a corresponding
1422 if (GatherArgumentsForCall(PlacementLParen, OperatorNew, Proto, 1,
1423 PlacementArgs, AllPlaceArgs, CallType))
1426 if (!AllPlaceArgs.empty())
1427 PlacementArgs = AllPlaceArgs;
1429 // FIXME: This is wrong: PlacementArgs misses out the first (size) argument.
1430 DiagnoseSentinelCalls(OperatorNew, PlacementLParen, PlacementArgs);
1432 // FIXME: Missing call to CheckFunctionCall or equivalent
1435 // Warn if the type is over-aligned and is being allocated by global operator
1437 if (PlacementArgs.empty() && OperatorNew &&
1438 (OperatorNew->isImplicit() ||
1439 getSourceManager().isInSystemHeader(OperatorNew->getLocStart()))) {
1440 if (unsigned Align = Context.getPreferredTypeAlign(AllocType.getTypePtr())){
1441 unsigned SuitableAlign = Context.getTargetInfo().getSuitableAlign();
1442 if (Align > SuitableAlign)
1443 Diag(StartLoc, diag::warn_overaligned_type)
1445 << unsigned(Align / Context.getCharWidth())
1446 << unsigned(SuitableAlign / Context.getCharWidth());
1450 QualType InitType = AllocType;
1451 // Array 'new' can't have any initializers except empty parentheses.
1452 // Initializer lists are also allowed, in C++11. Rely on the parser for the
1453 // dialect distinction.
1454 if (ResultType->isArrayType() || ArraySize) {
1455 if (!isLegalArrayNewInitializer(initStyle, Initializer)) {
1456 SourceRange InitRange(Inits[0]->getLocStart(),
1457 Inits[NumInits - 1]->getLocEnd());
1458 Diag(StartLoc, diag::err_new_array_init_args) << InitRange;
1461 if (InitListExpr *ILE = dyn_cast_or_null<InitListExpr>(Initializer)) {
1462 // We do the initialization typechecking against the array type
1463 // corresponding to the number of initializers + 1 (to also check
1464 // default-initialization).
1465 unsigned NumElements = ILE->getNumInits() + 1;
1466 InitType = Context.getConstantArrayType(AllocType,
1467 llvm::APInt(Context.getTypeSize(Context.getSizeType()), NumElements),
1468 ArrayType::Normal, 0);
1472 // If we can perform the initialization, and we've not already done so,
1474 if (!AllocType->isDependentType() &&
1475 !Expr::hasAnyTypeDependentArguments(
1476 llvm::makeArrayRef(Inits, NumInits))) {
1477 // C++11 [expr.new]p15:
1478 // A new-expression that creates an object of type T initializes that
1479 // object as follows:
1480 InitializationKind Kind
1481 // - If the new-initializer is omitted, the object is default-
1482 // initialized (8.5); if no initialization is performed,
1483 // the object has indeterminate value
1484 = initStyle == CXXNewExpr::NoInit
1485 ? InitializationKind::CreateDefault(TypeRange.getBegin())
1486 // - Otherwise, the new-initializer is interpreted according to the
1487 // initialization rules of 8.5 for direct-initialization.
1488 : initStyle == CXXNewExpr::ListInit
1489 ? InitializationKind::CreateDirectList(TypeRange.getBegin())
1490 : InitializationKind::CreateDirect(TypeRange.getBegin(),
1491 DirectInitRange.getBegin(),
1492 DirectInitRange.getEnd());
1494 InitializedEntity Entity
1495 = InitializedEntity::InitializeNew(StartLoc, InitType);
1496 InitializationSequence InitSeq(*this, Entity, Kind, MultiExprArg(Inits, NumInits));
1497 ExprResult FullInit = InitSeq.Perform(*this, Entity, Kind,
1498 MultiExprArg(Inits, NumInits));
1499 if (FullInit.isInvalid())
1502 // FullInit is our initializer; strip off CXXBindTemporaryExprs, because
1503 // we don't want the initialized object to be destructed.
1504 if (CXXBindTemporaryExpr *Binder =
1505 dyn_cast_or_null<CXXBindTemporaryExpr>(FullInit.get()))
1506 FullInit = Binder->getSubExpr();
1508 Initializer = FullInit.get();
1511 // Mark the new and delete operators as referenced.
1513 if (DiagnoseUseOfDecl(OperatorNew, StartLoc))
1515 MarkFunctionReferenced(StartLoc, OperatorNew);
1517 if (OperatorDelete) {
1518 if (DiagnoseUseOfDecl(OperatorDelete, StartLoc))
1520 MarkFunctionReferenced(StartLoc, OperatorDelete);
1523 // C++0x [expr.new]p17:
1524 // If the new expression creates an array of objects of class type,
1525 // access and ambiguity control are done for the destructor.
1526 QualType BaseAllocType = Context.getBaseElementType(AllocType);
1527 if (ArraySize && !BaseAllocType->isDependentType()) {
1528 if (const RecordType *BaseRecordType = BaseAllocType->getAs<RecordType>()) {
1529 if (CXXDestructorDecl *dtor = LookupDestructor(
1530 cast<CXXRecordDecl>(BaseRecordType->getDecl()))) {
1531 MarkFunctionReferenced(StartLoc, dtor);
1532 CheckDestructorAccess(StartLoc, dtor,
1533 PDiag(diag::err_access_dtor)
1535 if (DiagnoseUseOfDecl(dtor, StartLoc))
1541 return new (Context)
1542 CXXNewExpr(Context, UseGlobal, OperatorNew, OperatorDelete,
1543 UsualArrayDeleteWantsSize, PlacementArgs, TypeIdParens,
1544 ArraySize, initStyle, Initializer, ResultType, AllocTypeInfo,
1545 Range, DirectInitRange);
1548 /// \brief Checks that a type is suitable as the allocated type
1549 /// in a new-expression.
1550 bool Sema::CheckAllocatedType(QualType AllocType, SourceLocation Loc,
1552 // C++ 5.3.4p1: "[The] type shall be a complete object type, but not an
1553 // abstract class type or array thereof.
1554 if (AllocType->isFunctionType())
1555 return Diag(Loc, diag::err_bad_new_type)
1556 << AllocType << 0 << R;
1557 else if (AllocType->isReferenceType())
1558 return Diag(Loc, diag::err_bad_new_type)
1559 << AllocType << 1 << R;
1560 else if (!AllocType->isDependentType() &&
1561 RequireCompleteType(Loc, AllocType, diag::err_new_incomplete_type,R))
1563 else if (RequireNonAbstractType(Loc, AllocType,
1564 diag::err_allocation_of_abstract_type))
1566 else if (AllocType->isVariablyModifiedType())
1567 return Diag(Loc, diag::err_variably_modified_new_type)
1569 else if (unsigned AddressSpace = AllocType.getAddressSpace())
1570 return Diag(Loc, diag::err_address_space_qualified_new)
1571 << AllocType.getUnqualifiedType() << AddressSpace;
1572 else if (getLangOpts().ObjCAutoRefCount) {
1573 if (const ArrayType *AT = Context.getAsArrayType(AllocType)) {
1574 QualType BaseAllocType = Context.getBaseElementType(AT);
1575 if (BaseAllocType.getObjCLifetime() == Qualifiers::OCL_None &&
1576 BaseAllocType->isObjCLifetimeType())
1577 return Diag(Loc, diag::err_arc_new_array_without_ownership)
1585 /// \brief Determine whether the given function is a non-placement
1586 /// deallocation function.
1587 static bool isNonPlacementDeallocationFunction(Sema &S, FunctionDecl *FD) {
1588 if (FD->isInvalidDecl())
1591 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FD))
1592 return Method->isUsualDeallocationFunction();
1594 if (FD->getOverloadedOperator() != OO_Delete &&
1595 FD->getOverloadedOperator() != OO_Array_Delete)
1598 if (FD->getNumParams() == 1)
1601 return S.getLangOpts().SizedDeallocation && FD->getNumParams() == 2 &&
1602 S.Context.hasSameUnqualifiedType(FD->getParamDecl(1)->getType(),
1603 S.Context.getSizeType());
1606 /// FindAllocationFunctions - Finds the overloads of operator new and delete
1607 /// that are appropriate for the allocation.
1608 bool Sema::FindAllocationFunctions(SourceLocation StartLoc, SourceRange Range,
1609 bool UseGlobal, QualType AllocType,
1610 bool IsArray, MultiExprArg PlaceArgs,
1611 FunctionDecl *&OperatorNew,
1612 FunctionDecl *&OperatorDelete) {
1613 // --- Choosing an allocation function ---
1614 // C++ 5.3.4p8 - 14 & 18
1615 // 1) If UseGlobal is true, only look in the global scope. Else, also look
1616 // in the scope of the allocated class.
1617 // 2) If an array size is given, look for operator new[], else look for
1619 // 3) The first argument is always size_t. Append the arguments from the
1622 SmallVector<Expr*, 8> AllocArgs(1 + PlaceArgs.size());
1623 // We don't care about the actual value of this argument.
1624 // FIXME: Should the Sema create the expression and embed it in the syntax
1625 // tree? Or should the consumer just recalculate the value?
1626 IntegerLiteral Size(Context, llvm::APInt::getNullValue(
1627 Context.getTargetInfo().getPointerWidth(0)),
1628 Context.getSizeType(),
1630 AllocArgs[0] = &Size;
1631 std::copy(PlaceArgs.begin(), PlaceArgs.end(), AllocArgs.begin() + 1);
1633 // C++ [expr.new]p8:
1634 // If the allocated type is a non-array type, the allocation
1635 // function's name is operator new and the deallocation function's
1636 // name is operator delete. If the allocated type is an array
1637 // type, the allocation function's name is operator new[] and the
1638 // deallocation function's name is operator delete[].
1639 DeclarationName NewName = Context.DeclarationNames.getCXXOperatorName(
1640 IsArray ? OO_Array_New : OO_New);
1641 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
1642 IsArray ? OO_Array_Delete : OO_Delete);
1644 QualType AllocElemType = Context.getBaseElementType(AllocType);
1646 if (AllocElemType->isRecordType() && !UseGlobal) {
1647 CXXRecordDecl *Record
1648 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl());
1649 if (FindAllocationOverload(StartLoc, Range, NewName, AllocArgs, Record,
1650 /*AllowMissing=*/true, OperatorNew))
1655 // Didn't find a member overload. Look for a global one.
1656 DeclareGlobalNewDelete();
1657 DeclContext *TUDecl = Context.getTranslationUnitDecl();
1658 bool FallbackEnabled = IsArray && Context.getLangOpts().MSVCCompat;
1659 if (FindAllocationOverload(StartLoc, Range, NewName, AllocArgs, TUDecl,
1660 /*AllowMissing=*/FallbackEnabled, OperatorNew,
1661 /*Diagnose=*/!FallbackEnabled)) {
1662 if (!FallbackEnabled)
1665 // MSVC will fall back on trying to find a matching global operator new
1666 // if operator new[] cannot be found. Also, MSVC will leak by not
1667 // generating a call to operator delete or operator delete[], but we
1668 // will not replicate that bug.
1669 NewName = Context.DeclarationNames.getCXXOperatorName(OO_New);
1670 DeleteName = Context.DeclarationNames.getCXXOperatorName(OO_Delete);
1671 if (FindAllocationOverload(StartLoc, Range, NewName, AllocArgs, TUDecl,
1672 /*AllowMissing=*/false, OperatorNew))
1677 // We don't need an operator delete if we're running under
1679 if (!getLangOpts().Exceptions) {
1680 OperatorDelete = nullptr;
1684 // C++ [expr.new]p19:
1686 // If the new-expression begins with a unary :: operator, the
1687 // deallocation function's name is looked up in the global
1688 // scope. Otherwise, if the allocated type is a class type T or an
1689 // array thereof, the deallocation function's name is looked up in
1690 // the scope of T. If this lookup fails to find the name, or if
1691 // the allocated type is not a class type or array thereof, the
1692 // deallocation function's name is looked up in the global scope.
1693 LookupResult FoundDelete(*this, DeleteName, StartLoc, LookupOrdinaryName);
1694 if (AllocElemType->isRecordType() && !UseGlobal) {
1696 = cast<CXXRecordDecl>(AllocElemType->getAs<RecordType>()->getDecl());
1697 LookupQualifiedName(FoundDelete, RD);
1699 if (FoundDelete.isAmbiguous())
1700 return true; // FIXME: clean up expressions?
1702 if (FoundDelete.empty()) {
1703 DeclareGlobalNewDelete();
1704 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
1707 FoundDelete.suppressDiagnostics();
1709 SmallVector<std::pair<DeclAccessPair,FunctionDecl*>, 2> Matches;
1711 // Whether we're looking for a placement operator delete is dictated
1712 // by whether we selected a placement operator new, not by whether
1713 // we had explicit placement arguments. This matters for things like
1714 // struct A { void *operator new(size_t, int = 0); ... };
1716 bool isPlacementNew = (!PlaceArgs.empty() || OperatorNew->param_size() != 1);
1718 if (isPlacementNew) {
1719 // C++ [expr.new]p20:
1720 // A declaration of a placement deallocation function matches the
1721 // declaration of a placement allocation function if it has the
1722 // same number of parameters and, after parameter transformations
1723 // (8.3.5), all parameter types except the first are
1726 // To perform this comparison, we compute the function type that
1727 // the deallocation function should have, and use that type both
1728 // for template argument deduction and for comparison purposes.
1730 // FIXME: this comparison should ignore CC and the like.
1731 QualType ExpectedFunctionType;
1733 const FunctionProtoType *Proto
1734 = OperatorNew->getType()->getAs<FunctionProtoType>();
1736 SmallVector<QualType, 4> ArgTypes;
1737 ArgTypes.push_back(Context.VoidPtrTy);
1738 for (unsigned I = 1, N = Proto->getNumParams(); I < N; ++I)
1739 ArgTypes.push_back(Proto->getParamType(I));
1741 FunctionProtoType::ExtProtoInfo EPI;
1742 EPI.Variadic = Proto->isVariadic();
1744 ExpectedFunctionType
1745 = Context.getFunctionType(Context.VoidTy, ArgTypes, EPI);
1748 for (LookupResult::iterator D = FoundDelete.begin(),
1749 DEnd = FoundDelete.end();
1751 FunctionDecl *Fn = nullptr;
1752 if (FunctionTemplateDecl *FnTmpl
1753 = dyn_cast<FunctionTemplateDecl>((*D)->getUnderlyingDecl())) {
1754 // Perform template argument deduction to try to match the
1755 // expected function type.
1756 TemplateDeductionInfo Info(StartLoc);
1757 if (DeduceTemplateArguments(FnTmpl, nullptr, ExpectedFunctionType, Fn,
1761 Fn = cast<FunctionDecl>((*D)->getUnderlyingDecl());
1763 if (Context.hasSameType(Fn->getType(), ExpectedFunctionType))
1764 Matches.push_back(std::make_pair(D.getPair(), Fn));
1767 // C++ [expr.new]p20:
1768 // [...] Any non-placement deallocation function matches a
1769 // non-placement allocation function. [...]
1770 for (LookupResult::iterator D = FoundDelete.begin(),
1771 DEnd = FoundDelete.end();
1773 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>((*D)->getUnderlyingDecl()))
1774 if (isNonPlacementDeallocationFunction(*this, Fn))
1775 Matches.push_back(std::make_pair(D.getPair(), Fn));
1778 // C++1y [expr.new]p22:
1779 // For a non-placement allocation function, the normal deallocation
1780 // function lookup is used
1781 // C++1y [expr.delete]p?:
1782 // If [...] deallocation function lookup finds both a usual deallocation
1783 // function with only a pointer parameter and a usual deallocation
1784 // function with both a pointer parameter and a size parameter, then the
1785 // selected deallocation function shall be the one with two parameters.
1786 // Otherwise, the selected deallocation function shall be the function
1787 // with one parameter.
1788 if (getLangOpts().SizedDeallocation && Matches.size() == 2) {
1789 if (Matches[0].second->getNumParams() == 1)
1790 Matches.erase(Matches.begin());
1792 Matches.erase(Matches.begin() + 1);
1793 assert(Matches[0].second->getNumParams() == 2 &&
1794 "found an unexpected usual deallocation function");
1798 // C++ [expr.new]p20:
1799 // [...] If the lookup finds a single matching deallocation
1800 // function, that function will be called; otherwise, no
1801 // deallocation function will be called.
1802 if (Matches.size() == 1) {
1803 OperatorDelete = Matches[0].second;
1805 // C++0x [expr.new]p20:
1806 // If the lookup finds the two-parameter form of a usual
1807 // deallocation function (3.7.4.2) and that function, considered
1808 // as a placement deallocation function, would have been
1809 // selected as a match for the allocation function, the program
1811 if (!PlaceArgs.empty() && getLangOpts().CPlusPlus11 &&
1812 isNonPlacementDeallocationFunction(*this, OperatorDelete)) {
1813 Diag(StartLoc, diag::err_placement_new_non_placement_delete)
1814 << SourceRange(PlaceArgs.front()->getLocStart(),
1815 PlaceArgs.back()->getLocEnd());
1816 if (!OperatorDelete->isImplicit())
1817 Diag(OperatorDelete->getLocation(), diag::note_previous_decl)
1820 CheckAllocationAccess(StartLoc, Range, FoundDelete.getNamingClass(),
1828 /// \brief Find an fitting overload for the allocation function
1829 /// in the specified scope.
1831 /// \param StartLoc The location of the 'new' token.
1832 /// \param Range The range of the placement arguments.
1833 /// \param Name The name of the function ('operator new' or 'operator new[]').
1834 /// \param Args The placement arguments specified.
1835 /// \param Ctx The scope in which we should search; either a class scope or the
1836 /// translation unit.
1837 /// \param AllowMissing If \c true, report an error if we can't find any
1838 /// allocation functions. Otherwise, succeed but don't fill in \p
1840 /// \param Operator Filled in with the found allocation function. Unchanged if
1841 /// no allocation function was found.
1842 /// \param Diagnose If \c true, issue errors if the allocation function is not
1844 bool Sema::FindAllocationOverload(SourceLocation StartLoc, SourceRange Range,
1845 DeclarationName Name, MultiExprArg Args,
1847 bool AllowMissing, FunctionDecl *&Operator,
1849 LookupResult R(*this, Name, StartLoc, LookupOrdinaryName);
1850 LookupQualifiedName(R, Ctx);
1852 if (AllowMissing || !Diagnose)
1854 return Diag(StartLoc, diag::err_ovl_no_viable_function_in_call)
1858 if (R.isAmbiguous())
1861 R.suppressDiagnostics();
1863 OverloadCandidateSet Candidates(StartLoc, OverloadCandidateSet::CSK_Normal);
1864 for (LookupResult::iterator Alloc = R.begin(), AllocEnd = R.end();
1865 Alloc != AllocEnd; ++Alloc) {
1866 // Even member operator new/delete are implicitly treated as
1867 // static, so don't use AddMemberCandidate.
1868 NamedDecl *D = (*Alloc)->getUnderlyingDecl();
1870 if (FunctionTemplateDecl *FnTemplate = dyn_cast<FunctionTemplateDecl>(D)) {
1871 AddTemplateOverloadCandidate(FnTemplate, Alloc.getPair(),
1872 /*ExplicitTemplateArgs=*/nullptr,
1874 /*SuppressUserConversions=*/false);
1878 FunctionDecl *Fn = cast<FunctionDecl>(D);
1879 AddOverloadCandidate(Fn, Alloc.getPair(), Args, Candidates,
1880 /*SuppressUserConversions=*/false);
1883 // Do the resolution.
1884 OverloadCandidateSet::iterator Best;
1885 switch (Candidates.BestViableFunction(*this, StartLoc, Best)) {
1888 FunctionDecl *FnDecl = Best->Function;
1889 if (CheckAllocationAccess(StartLoc, Range, R.getNamingClass(),
1890 Best->FoundDecl, Diagnose) == AR_inaccessible)
1897 case OR_No_Viable_Function:
1899 Diag(StartLoc, diag::err_ovl_no_viable_function_in_call)
1901 Candidates.NoteCandidates(*this, OCD_AllCandidates, Args);
1907 Diag(StartLoc, diag::err_ovl_ambiguous_call)
1909 Candidates.NoteCandidates(*this, OCD_ViableCandidates, Args);
1915 Diag(StartLoc, diag::err_ovl_deleted_call)
1916 << Best->Function->isDeleted()
1918 << getDeletedOrUnavailableSuffix(Best->Function)
1920 Candidates.NoteCandidates(*this, OCD_AllCandidates, Args);
1925 llvm_unreachable("Unreachable, bad result from BestViableFunction");
1929 /// DeclareGlobalNewDelete - Declare the global forms of operator new and
1930 /// delete. These are:
1933 /// void* operator new(std::size_t) throw(std::bad_alloc);
1934 /// void* operator new[](std::size_t) throw(std::bad_alloc);
1935 /// void operator delete(void *) throw();
1936 /// void operator delete[](void *) throw();
1938 /// void* operator new(std::size_t);
1939 /// void* operator new[](std::size_t);
1940 /// void operator delete(void *) noexcept;
1941 /// void operator delete[](void *) noexcept;
1943 /// void* operator new(std::size_t);
1944 /// void* operator new[](std::size_t);
1945 /// void operator delete(void *) noexcept;
1946 /// void operator delete[](void *) noexcept;
1947 /// void operator delete(void *, std::size_t) noexcept;
1948 /// void operator delete[](void *, std::size_t) noexcept;
1950 /// Note that the placement and nothrow forms of new are *not* implicitly
1951 /// declared. Their use requires including \<new\>.
1952 void Sema::DeclareGlobalNewDelete() {
1953 if (GlobalNewDeleteDeclared)
1956 // C++ [basic.std.dynamic]p2:
1957 // [...] The following allocation and deallocation functions (18.4) are
1958 // implicitly declared in global scope in each translation unit of a
1962 // void* operator new(std::size_t) throw(std::bad_alloc);
1963 // void* operator new[](std::size_t) throw(std::bad_alloc);
1964 // void operator delete(void*) throw();
1965 // void operator delete[](void*) throw();
1967 // void* operator new(std::size_t);
1968 // void* operator new[](std::size_t);
1969 // void operator delete(void*) noexcept;
1970 // void operator delete[](void*) noexcept;
1972 // void* operator new(std::size_t);
1973 // void* operator new[](std::size_t);
1974 // void operator delete(void*) noexcept;
1975 // void operator delete[](void*) noexcept;
1976 // void operator delete(void*, std::size_t) noexcept;
1977 // void operator delete[](void*, std::size_t) noexcept;
1979 // These implicit declarations introduce only the function names operator
1980 // new, operator new[], operator delete, operator delete[].
1982 // Here, we need to refer to std::bad_alloc, so we will implicitly declare
1983 // "std" or "bad_alloc" as necessary to form the exception specification.
1984 // However, we do not make these implicit declarations visible to name
1986 if (!StdBadAlloc && !getLangOpts().CPlusPlus11) {
1987 // The "std::bad_alloc" class has not yet been declared, so build it
1989 StdBadAlloc = CXXRecordDecl::Create(Context, TTK_Class,
1990 getOrCreateStdNamespace(),
1991 SourceLocation(), SourceLocation(),
1992 &PP.getIdentifierTable().get("bad_alloc"),
1994 getStdBadAlloc()->setImplicit(true);
1997 GlobalNewDeleteDeclared = true;
1999 QualType VoidPtr = Context.getPointerType(Context.VoidTy);
2000 QualType SizeT = Context.getSizeType();
2001 bool AssumeSaneOperatorNew = getLangOpts().AssumeSaneOperatorNew;
2003 DeclareGlobalAllocationFunction(
2004 Context.DeclarationNames.getCXXOperatorName(OO_New),
2005 VoidPtr, SizeT, QualType(), AssumeSaneOperatorNew);
2006 DeclareGlobalAllocationFunction(
2007 Context.DeclarationNames.getCXXOperatorName(OO_Array_New),
2008 VoidPtr, SizeT, QualType(), AssumeSaneOperatorNew);
2009 DeclareGlobalAllocationFunction(
2010 Context.DeclarationNames.getCXXOperatorName(OO_Delete),
2011 Context.VoidTy, VoidPtr);
2012 DeclareGlobalAllocationFunction(
2013 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete),
2014 Context.VoidTy, VoidPtr);
2015 if (getLangOpts().SizedDeallocation) {
2016 DeclareGlobalAllocationFunction(
2017 Context.DeclarationNames.getCXXOperatorName(OO_Delete),
2018 Context.VoidTy, VoidPtr, Context.getSizeType());
2019 DeclareGlobalAllocationFunction(
2020 Context.DeclarationNames.getCXXOperatorName(OO_Array_Delete),
2021 Context.VoidTy, VoidPtr, Context.getSizeType());
2025 /// DeclareGlobalAllocationFunction - Declares a single implicit global
2026 /// allocation function if it doesn't already exist.
2027 void Sema::DeclareGlobalAllocationFunction(DeclarationName Name,
2029 QualType Param1, QualType Param2,
2030 bool AddMallocAttr) {
2031 DeclContext *GlobalCtx = Context.getTranslationUnitDecl();
2032 unsigned NumParams = Param2.isNull() ? 1 : 2;
2034 // Check if this function is already declared.
2035 DeclContext::lookup_result R = GlobalCtx->lookup(Name);
2036 for (DeclContext::lookup_iterator Alloc = R.begin(), AllocEnd = R.end();
2037 Alloc != AllocEnd; ++Alloc) {
2038 // Only look at non-template functions, as it is the predefined,
2039 // non-templated allocation function we are trying to declare here.
2040 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(*Alloc)) {
2041 if (Func->getNumParams() == NumParams) {
2042 QualType InitialParam1Type =
2043 Context.getCanonicalType(Func->getParamDecl(0)
2044 ->getType().getUnqualifiedType());
2045 QualType InitialParam2Type =
2047 ? Context.getCanonicalType(Func->getParamDecl(1)
2048 ->getType().getUnqualifiedType())
2050 // FIXME: Do we need to check for default arguments here?
2051 if (InitialParam1Type == Param1 &&
2052 (NumParams == 1 || InitialParam2Type == Param2)) {
2053 if (AddMallocAttr && !Func->hasAttr<MallocAttr>())
2054 Func->addAttr(MallocAttr::CreateImplicit(Context));
2055 // Make the function visible to name lookup, even if we found it in
2056 // an unimported module. It either is an implicitly-declared global
2057 // allocation function, or is suppressing that function.
2058 Func->setHidden(false);
2065 FunctionProtoType::ExtProtoInfo EPI;
2067 QualType BadAllocType;
2068 bool HasBadAllocExceptionSpec
2069 = (Name.getCXXOverloadedOperator() == OO_New ||
2070 Name.getCXXOverloadedOperator() == OO_Array_New);
2071 if (HasBadAllocExceptionSpec) {
2072 if (!getLangOpts().CPlusPlus11) {
2073 BadAllocType = Context.getTypeDeclType(getStdBadAlloc());
2074 assert(StdBadAlloc && "Must have std::bad_alloc declared");
2075 EPI.ExceptionSpecType = EST_Dynamic;
2076 EPI.NumExceptions = 1;
2077 EPI.Exceptions = &BadAllocType;
2080 EPI.ExceptionSpecType = getLangOpts().CPlusPlus11 ?
2081 EST_BasicNoexcept : EST_DynamicNone;
2084 QualType Params[] = { Param1, Param2 };
2086 QualType FnType = Context.getFunctionType(
2087 Return, ArrayRef<QualType>(Params, NumParams), EPI);
2088 FunctionDecl *Alloc =
2089 FunctionDecl::Create(Context, GlobalCtx, SourceLocation(),
2090 SourceLocation(), Name,
2091 FnType, /*TInfo=*/nullptr, SC_None, false, true);
2092 Alloc->setImplicit();
2095 Alloc->addAttr(MallocAttr::CreateImplicit(Context));
2097 ParmVarDecl *ParamDecls[2];
2098 for (unsigned I = 0; I != NumParams; ++I) {
2099 ParamDecls[I] = ParmVarDecl::Create(Context, Alloc, SourceLocation(),
2100 SourceLocation(), nullptr,
2101 Params[I], /*TInfo=*/nullptr,
2103 ParamDecls[I]->setImplicit();
2105 Alloc->setParams(ArrayRef<ParmVarDecl*>(ParamDecls, NumParams));
2107 Context.getTranslationUnitDecl()->addDecl(Alloc);
2108 IdResolver.tryAddTopLevelDecl(Alloc, Name);
2111 FunctionDecl *Sema::FindUsualDeallocationFunction(SourceLocation StartLoc,
2112 bool CanProvideSize,
2113 DeclarationName Name) {
2114 DeclareGlobalNewDelete();
2116 LookupResult FoundDelete(*this, Name, StartLoc, LookupOrdinaryName);
2117 LookupQualifiedName(FoundDelete, Context.getTranslationUnitDecl());
2119 // C++ [expr.new]p20:
2120 // [...] Any non-placement deallocation function matches a
2121 // non-placement allocation function. [...]
2122 llvm::SmallVector<FunctionDecl*, 2> Matches;
2123 for (LookupResult::iterator D = FoundDelete.begin(),
2124 DEnd = FoundDelete.end();
2126 if (FunctionDecl *Fn = dyn_cast<FunctionDecl>(*D))
2127 if (isNonPlacementDeallocationFunction(*this, Fn))
2128 Matches.push_back(Fn);
2131 // C++1y [expr.delete]p?:
2132 // If the type is complete and deallocation function lookup finds both a
2133 // usual deallocation function with only a pointer parameter and a usual
2134 // deallocation function with both a pointer parameter and a size
2135 // parameter, then the selected deallocation function shall be the one
2136 // with two parameters. Otherwise, the selected deallocation function
2137 // shall be the function with one parameter.
2138 if (getLangOpts().SizedDeallocation && Matches.size() == 2) {
2139 unsigned NumArgs = CanProvideSize ? 2 : 1;
2140 if (Matches[0]->getNumParams() != NumArgs)
2141 Matches.erase(Matches.begin());
2143 Matches.erase(Matches.begin() + 1);
2144 assert(Matches[0]->getNumParams() == NumArgs &&
2145 "found an unexpected usual deallocation function");
2148 assert(Matches.size() == 1 &&
2149 "unexpectedly have multiple usual deallocation functions");
2150 return Matches.front();
2153 bool Sema::FindDeallocationFunction(SourceLocation StartLoc, CXXRecordDecl *RD,
2154 DeclarationName Name,
2155 FunctionDecl* &Operator, bool Diagnose) {
2156 LookupResult Found(*this, Name, StartLoc, LookupOrdinaryName);
2157 // Try to find operator delete/operator delete[] in class scope.
2158 LookupQualifiedName(Found, RD);
2160 if (Found.isAmbiguous())
2163 Found.suppressDiagnostics();
2165 SmallVector<DeclAccessPair,4> Matches;
2166 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end();
2168 NamedDecl *ND = (*F)->getUnderlyingDecl();
2170 // Ignore template operator delete members from the check for a usual
2171 // deallocation function.
2172 if (isa<FunctionTemplateDecl>(ND))
2175 if (cast<CXXMethodDecl>(ND)->isUsualDeallocationFunction())
2176 Matches.push_back(F.getPair());
2179 // There's exactly one suitable operator; pick it.
2180 if (Matches.size() == 1) {
2181 Operator = cast<CXXMethodDecl>(Matches[0]->getUnderlyingDecl());
2183 if (Operator->isDeleted()) {
2185 Diag(StartLoc, diag::err_deleted_function_use);
2186 NoteDeletedFunction(Operator);
2191 if (CheckAllocationAccess(StartLoc, SourceRange(), Found.getNamingClass(),
2192 Matches[0], Diagnose) == AR_inaccessible)
2197 // We found multiple suitable operators; complain about the ambiguity.
2198 } else if (!Matches.empty()) {
2200 Diag(StartLoc, diag::err_ambiguous_suitable_delete_member_function_found)
2203 for (SmallVectorImpl<DeclAccessPair>::iterator
2204 F = Matches.begin(), FEnd = Matches.end(); F != FEnd; ++F)
2205 Diag((*F)->getUnderlyingDecl()->getLocation(),
2206 diag::note_member_declared_here) << Name;
2211 // We did find operator delete/operator delete[] declarations, but
2212 // none of them were suitable.
2213 if (!Found.empty()) {
2215 Diag(StartLoc, diag::err_no_suitable_delete_member_function_found)
2218 for (LookupResult::iterator F = Found.begin(), FEnd = Found.end();
2220 Diag((*F)->getUnderlyingDecl()->getLocation(),
2221 diag::note_member_declared_here) << Name;
2230 /// ActOnCXXDelete - Parsed a C++ 'delete' expression (C++ 5.3.5), as in:
2231 /// @code ::delete ptr; @endcode
2233 /// @code delete [] ptr; @endcode
2235 Sema::ActOnCXXDelete(SourceLocation StartLoc, bool UseGlobal,
2236 bool ArrayForm, Expr *ExE) {
2237 // C++ [expr.delete]p1:
2238 // The operand shall have a pointer type, or a class type having a single
2239 // non-explicit conversion function to a pointer type. The result has type
2242 // DR599 amends "pointer type" to "pointer to object type" in both cases.
2244 ExprResult Ex = ExE;
2245 FunctionDecl *OperatorDelete = nullptr;
2246 bool ArrayFormAsWritten = ArrayForm;
2247 bool UsualArrayDeleteWantsSize = false;
2249 if (!Ex.get()->isTypeDependent()) {
2250 // Perform lvalue-to-rvalue cast, if needed.
2251 Ex = DefaultLvalueConversion(Ex.get());
2255 QualType Type = Ex.get()->getType();
2257 class DeleteConverter : public ContextualImplicitConverter {
2259 DeleteConverter() : ContextualImplicitConverter(false, true) {}
2261 bool match(QualType ConvType) override {
2262 // FIXME: If we have an operator T* and an operator void*, we must pick
2264 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>())
2265 if (ConvPtrType->getPointeeType()->isIncompleteOrObjectType())
2270 SemaDiagnosticBuilder diagnoseNoMatch(Sema &S, SourceLocation Loc,
2271 QualType T) override {
2272 return S.Diag(Loc, diag::err_delete_operand) << T;
2275 SemaDiagnosticBuilder diagnoseIncomplete(Sema &S, SourceLocation Loc,
2276 QualType T) override {
2277 return S.Diag(Loc, diag::err_delete_incomplete_class_type) << T;
2280 SemaDiagnosticBuilder diagnoseExplicitConv(Sema &S, SourceLocation Loc,
2282 QualType ConvTy) override {
2283 return S.Diag(Loc, diag::err_delete_explicit_conversion) << T << ConvTy;
2286 SemaDiagnosticBuilder noteExplicitConv(Sema &S, CXXConversionDecl *Conv,
2287 QualType ConvTy) override {
2288 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
2292 SemaDiagnosticBuilder diagnoseAmbiguous(Sema &S, SourceLocation Loc,
2293 QualType T) override {
2294 return S.Diag(Loc, diag::err_ambiguous_delete_operand) << T;
2297 SemaDiagnosticBuilder noteAmbiguous(Sema &S, CXXConversionDecl *Conv,
2298 QualType ConvTy) override {
2299 return S.Diag(Conv->getLocation(), diag::note_delete_conversion)
2303 SemaDiagnosticBuilder diagnoseConversion(Sema &S, SourceLocation Loc,
2305 QualType ConvTy) override {
2306 llvm_unreachable("conversion functions are permitted");
2310 Ex = PerformContextualImplicitConversion(StartLoc, Ex.get(), Converter);
2313 Type = Ex.get()->getType();
2314 if (!Converter.match(Type))
2315 // FIXME: PerformContextualImplicitConversion should return ExprError
2316 // itself in this case.
2319 QualType Pointee = Type->getAs<PointerType>()->getPointeeType();
2320 QualType PointeeElem = Context.getBaseElementType(Pointee);
2322 if (unsigned AddressSpace = Pointee.getAddressSpace())
2323 return Diag(Ex.get()->getLocStart(),
2324 diag::err_address_space_qualified_delete)
2325 << Pointee.getUnqualifiedType() << AddressSpace;
2327 CXXRecordDecl *PointeeRD = nullptr;
2328 if (Pointee->isVoidType() && !isSFINAEContext()) {
2329 // The C++ standard bans deleting a pointer to a non-object type, which
2330 // effectively bans deletion of "void*". However, most compilers support
2331 // this, so we treat it as a warning unless we're in a SFINAE context.
2332 Diag(StartLoc, diag::ext_delete_void_ptr_operand)
2333 << Type << Ex.get()->getSourceRange();
2334 } else if (Pointee->isFunctionType() || Pointee->isVoidType()) {
2335 return ExprError(Diag(StartLoc, diag::err_delete_operand)
2336 << Type << Ex.get()->getSourceRange());
2337 } else if (!Pointee->isDependentType()) {
2338 if (!RequireCompleteType(StartLoc, Pointee,
2339 diag::warn_delete_incomplete, Ex.get())) {
2340 if (const RecordType *RT = PointeeElem->getAs<RecordType>())
2341 PointeeRD = cast<CXXRecordDecl>(RT->getDecl());
2345 // C++ [expr.delete]p2:
2346 // [Note: a pointer to a const type can be the operand of a
2347 // delete-expression; it is not necessary to cast away the constness
2348 // (5.2.11) of the pointer expression before it is used as the operand
2349 // of the delete-expression. ]
2351 if (Pointee->isArrayType() && !ArrayForm) {
2352 Diag(StartLoc, diag::warn_delete_array_type)
2353 << Type << Ex.get()->getSourceRange()
2354 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(StartLoc), "[]");
2358 DeclarationName DeleteName = Context.DeclarationNames.getCXXOperatorName(
2359 ArrayForm ? OO_Array_Delete : OO_Delete);
2363 FindDeallocationFunction(StartLoc, PointeeRD, DeleteName,
2367 // If we're allocating an array of records, check whether the
2368 // usual operator delete[] has a size_t parameter.
2370 // If the user specifically asked to use the global allocator,
2371 // we'll need to do the lookup into the class.
2373 UsualArrayDeleteWantsSize =
2374 doesUsualArrayDeleteWantSize(*this, StartLoc, PointeeElem);
2376 // Otherwise, the usual operator delete[] should be the
2377 // function we just found.
2378 else if (OperatorDelete && isa<CXXMethodDecl>(OperatorDelete))
2379 UsualArrayDeleteWantsSize = (OperatorDelete->getNumParams() == 2);
2382 if (!PointeeRD->hasIrrelevantDestructor())
2383 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
2384 MarkFunctionReferenced(StartLoc,
2385 const_cast<CXXDestructorDecl*>(Dtor));
2386 if (DiagnoseUseOfDecl(Dtor, StartLoc))
2390 // C++ [expr.delete]p3:
2391 // In the first alternative (delete object), if the static type of the
2392 // object to be deleted is different from its dynamic type, the static
2393 // type shall be a base class of the dynamic type of the object to be
2394 // deleted and the static type shall have a virtual destructor or the
2395 // behavior is undefined.
2397 // Note: a final class cannot be derived from, no issue there
2398 if (PointeeRD->isPolymorphic() && !PointeeRD->hasAttr<FinalAttr>()) {
2399 CXXDestructorDecl *dtor = PointeeRD->getDestructor();
2400 if (dtor && !dtor->isVirtual()) {
2401 if (PointeeRD->isAbstract()) {
2402 // If the class is abstract, we warn by default, because we're
2403 // sure the code has undefined behavior.
2404 Diag(StartLoc, diag::warn_delete_abstract_non_virtual_dtor)
2406 } else if (!ArrayForm) {
2407 // Otherwise, if this is not an array delete, it's a bit suspect,
2408 // but not necessarily wrong.
2409 Diag(StartLoc, diag::warn_delete_non_virtual_dtor) << PointeeElem;
2416 if (!OperatorDelete)
2417 // Look for a global declaration.
2418 OperatorDelete = FindUsualDeallocationFunction(
2419 StartLoc, !RequireCompleteType(StartLoc, Pointee, 0) &&
2420 (!ArrayForm || UsualArrayDeleteWantsSize ||
2421 Pointee.isDestructedType()),
2424 MarkFunctionReferenced(StartLoc, OperatorDelete);
2426 // Check access and ambiguity of operator delete and destructor.
2428 if (CXXDestructorDecl *Dtor = LookupDestructor(PointeeRD)) {
2429 CheckDestructorAccess(Ex.get()->getExprLoc(), Dtor,
2430 PDiag(diag::err_access_dtor) << PointeeElem);
2435 return new (Context) CXXDeleteExpr(
2436 Context.VoidTy, UseGlobal, ArrayForm, ArrayFormAsWritten,
2437 UsualArrayDeleteWantsSize, OperatorDelete, Ex.get(), StartLoc);
2440 /// \brief Check the use of the given variable as a C++ condition in an if,
2441 /// while, do-while, or switch statement.
2442 ExprResult Sema::CheckConditionVariable(VarDecl *ConditionVar,
2443 SourceLocation StmtLoc,
2444 bool ConvertToBoolean) {
2445 if (ConditionVar->isInvalidDecl())
2448 QualType T = ConditionVar->getType();
2450 // C++ [stmt.select]p2:
2451 // The declarator shall not specify a function or an array.
2452 if (T->isFunctionType())
2453 return ExprError(Diag(ConditionVar->getLocation(),
2454 diag::err_invalid_use_of_function_type)
2455 << ConditionVar->getSourceRange());
2456 else if (T->isArrayType())
2457 return ExprError(Diag(ConditionVar->getLocation(),
2458 diag::err_invalid_use_of_array_type)
2459 << ConditionVar->getSourceRange());
2461 ExprResult Condition = DeclRefExpr::Create(
2462 Context, NestedNameSpecifierLoc(), SourceLocation(), ConditionVar,
2463 /*enclosing*/ false, ConditionVar->getLocation(),
2464 ConditionVar->getType().getNonReferenceType(), VK_LValue);
2466 MarkDeclRefReferenced(cast<DeclRefExpr>(Condition.get()));
2468 if (ConvertToBoolean) {
2469 Condition = CheckBooleanCondition(Condition.get(), StmtLoc);
2470 if (Condition.isInvalid())
2477 /// CheckCXXBooleanCondition - Returns true if a conversion to bool is invalid.
2478 ExprResult Sema::CheckCXXBooleanCondition(Expr *CondExpr) {
2480 // The value of a condition that is an initialized declaration in a statement
2481 // other than a switch statement is the value of the declared variable
2482 // implicitly converted to type bool. If that conversion is ill-formed, the
2483 // program is ill-formed.
2484 // The value of a condition that is an expression is the value of the
2485 // expression, implicitly converted to bool.
2487 return PerformContextuallyConvertToBool(CondExpr);
2490 /// Helper function to determine whether this is the (deprecated) C++
2491 /// conversion from a string literal to a pointer to non-const char or
2492 /// non-const wchar_t (for narrow and wide string literals,
2495 Sema::IsStringLiteralToNonConstPointerConversion(Expr *From, QualType ToType) {
2496 // Look inside the implicit cast, if it exists.
2497 if (ImplicitCastExpr *Cast = dyn_cast<ImplicitCastExpr>(From))
2498 From = Cast->getSubExpr();
2500 // A string literal (2.13.4) that is not a wide string literal can
2501 // be converted to an rvalue of type "pointer to char"; a wide
2502 // string literal can be converted to an rvalue of type "pointer
2503 // to wchar_t" (C++ 4.2p2).
2504 if (StringLiteral *StrLit = dyn_cast<StringLiteral>(From->IgnoreParens()))
2505 if (const PointerType *ToPtrType = ToType->getAs<PointerType>())
2506 if (const BuiltinType *ToPointeeType
2507 = ToPtrType->getPointeeType()->getAs<BuiltinType>()) {
2508 // This conversion is considered only when there is an
2509 // explicit appropriate pointer target type (C++ 4.2p2).
2510 if (!ToPtrType->getPointeeType().hasQualifiers()) {
2511 switch (StrLit->getKind()) {
2512 case StringLiteral::UTF8:
2513 case StringLiteral::UTF16:
2514 case StringLiteral::UTF32:
2515 // We don't allow UTF literals to be implicitly converted
2517 case StringLiteral::Ascii:
2518 return (ToPointeeType->getKind() == BuiltinType::Char_U ||
2519 ToPointeeType->getKind() == BuiltinType::Char_S);
2520 case StringLiteral::Wide:
2521 return ToPointeeType->isWideCharType();
2529 static ExprResult BuildCXXCastArgument(Sema &S,
2530 SourceLocation CastLoc,
2533 CXXMethodDecl *Method,
2534 DeclAccessPair FoundDecl,
2535 bool HadMultipleCandidates,
2538 default: llvm_unreachable("Unhandled cast kind!");
2539 case CK_ConstructorConversion: {
2540 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Method);
2541 SmallVector<Expr*, 8> ConstructorArgs;
2543 if (S.RequireNonAbstractType(CastLoc, Ty,
2544 diag::err_allocation_of_abstract_type))
2547 if (S.CompleteConstructorCall(Constructor, From, CastLoc, ConstructorArgs))
2550 S.CheckConstructorAccess(CastLoc, Constructor,
2551 InitializedEntity::InitializeTemporary(Ty),
2552 Constructor->getAccess());
2554 ExprResult Result = S.BuildCXXConstructExpr(
2555 CastLoc, Ty, cast<CXXConstructorDecl>(Method),
2556 ConstructorArgs, HadMultipleCandidates,
2557 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
2558 CXXConstructExpr::CK_Complete, SourceRange());
2559 if (Result.isInvalid())
2562 return S.MaybeBindToTemporary(Result.getAs<Expr>());
2565 case CK_UserDefinedConversion: {
2566 assert(!From->getType()->isPointerType() && "Arg can't have pointer type!");
2568 // Create an implicit call expr that calls it.
2569 CXXConversionDecl *Conv = cast<CXXConversionDecl>(Method);
2570 ExprResult Result = S.BuildCXXMemberCallExpr(From, FoundDecl, Conv,
2571 HadMultipleCandidates);
2572 if (Result.isInvalid())
2574 // Record usage of conversion in an implicit cast.
2575 Result = ImplicitCastExpr::Create(S.Context, Result.get()->getType(),
2576 CK_UserDefinedConversion, Result.get(),
2577 nullptr, Result.get()->getValueKind());
2579 S.CheckMemberOperatorAccess(CastLoc, From, /*arg*/ nullptr, FoundDecl);
2581 return S.MaybeBindToTemporary(Result.get());
2586 /// PerformImplicitConversion - Perform an implicit conversion of the
2587 /// expression From to the type ToType using the pre-computed implicit
2588 /// conversion sequence ICS. Returns the converted
2589 /// expression. Action is the kind of conversion we're performing,
2590 /// used in the error message.
2592 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
2593 const ImplicitConversionSequence &ICS,
2594 AssignmentAction Action,
2595 CheckedConversionKind CCK) {
2596 switch (ICS.getKind()) {
2597 case ImplicitConversionSequence::StandardConversion: {
2598 ExprResult Res = PerformImplicitConversion(From, ToType, ICS.Standard,
2600 if (Res.isInvalid())
2606 case ImplicitConversionSequence::UserDefinedConversion: {
2608 FunctionDecl *FD = ICS.UserDefined.ConversionFunction;
2610 QualType BeforeToType;
2611 assert(FD && "FIXME: aggregate initialization from init list");
2612 if (const CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(FD)) {
2613 CastKind = CK_UserDefinedConversion;
2615 // If the user-defined conversion is specified by a conversion function,
2616 // the initial standard conversion sequence converts the source type to
2617 // the implicit object parameter of the conversion function.
2618 BeforeToType = Context.getTagDeclType(Conv->getParent());
2620 const CXXConstructorDecl *Ctor = cast<CXXConstructorDecl>(FD);
2621 CastKind = CK_ConstructorConversion;
2622 // Do no conversion if dealing with ... for the first conversion.
2623 if (!ICS.UserDefined.EllipsisConversion) {
2624 // If the user-defined conversion is specified by a constructor, the
2625 // initial standard conversion sequence converts the source type to the
2626 // type required by the argument of the constructor
2627 BeforeToType = Ctor->getParamDecl(0)->getType().getNonReferenceType();
2630 // Watch out for ellipsis conversion.
2631 if (!ICS.UserDefined.EllipsisConversion) {
2633 PerformImplicitConversion(From, BeforeToType,
2634 ICS.UserDefined.Before, AA_Converting,
2636 if (Res.isInvalid())
2642 = BuildCXXCastArgument(*this,
2643 From->getLocStart(),
2644 ToType.getNonReferenceType(),
2645 CastKind, cast<CXXMethodDecl>(FD),
2646 ICS.UserDefined.FoundConversionFunction,
2647 ICS.UserDefined.HadMultipleCandidates,
2650 if (CastArg.isInvalid())
2653 From = CastArg.get();
2655 return PerformImplicitConversion(From, ToType, ICS.UserDefined.After,
2656 AA_Converting, CCK);
2659 case ImplicitConversionSequence::AmbiguousConversion:
2660 ICS.DiagnoseAmbiguousConversion(*this, From->getExprLoc(),
2661 PDiag(diag::err_typecheck_ambiguous_condition)
2662 << From->getSourceRange());
2665 case ImplicitConversionSequence::EllipsisConversion:
2666 llvm_unreachable("Cannot perform an ellipsis conversion");
2668 case ImplicitConversionSequence::BadConversion:
2672 // Everything went well.
2676 /// PerformImplicitConversion - Perform an implicit conversion of the
2677 /// expression From to the type ToType by following the standard
2678 /// conversion sequence SCS. Returns the converted
2679 /// expression. Flavor is the context in which we're performing this
2680 /// conversion, for use in error messages.
2682 Sema::PerformImplicitConversion(Expr *From, QualType ToType,
2683 const StandardConversionSequence& SCS,
2684 AssignmentAction Action,
2685 CheckedConversionKind CCK) {
2686 bool CStyle = (CCK == CCK_CStyleCast || CCK == CCK_FunctionalCast);
2688 // Overall FIXME: we are recomputing too many types here and doing far too
2689 // much extra work. What this means is that we need to keep track of more
2690 // information that is computed when we try the implicit conversion initially,
2691 // so that we don't need to recompute anything here.
2692 QualType FromType = From->getType();
2694 if (SCS.CopyConstructor) {
2695 // FIXME: When can ToType be a reference type?
2696 assert(!ToType->isReferenceType());
2697 if (SCS.Second == ICK_Derived_To_Base) {
2698 SmallVector<Expr*, 8> ConstructorArgs;
2699 if (CompleteConstructorCall(cast<CXXConstructorDecl>(SCS.CopyConstructor),
2700 From, /*FIXME:ConstructLoc*/SourceLocation(),
2703 return BuildCXXConstructExpr(
2704 /*FIXME:ConstructLoc*/ SourceLocation(), ToType, SCS.CopyConstructor,
2705 ConstructorArgs, /*HadMultipleCandidates*/ false,
2706 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
2707 CXXConstructExpr::CK_Complete, SourceRange());
2709 return BuildCXXConstructExpr(
2710 /*FIXME:ConstructLoc*/ SourceLocation(), ToType, SCS.CopyConstructor,
2711 From, /*HadMultipleCandidates*/ false,
2712 /*ListInit*/ false, /*StdInitListInit*/ false, /*ZeroInit*/ false,
2713 CXXConstructExpr::CK_Complete, SourceRange());
2716 // Resolve overloaded function references.
2717 if (Context.hasSameType(FromType, Context.OverloadTy)) {
2718 DeclAccessPair Found;
2719 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(From, ToType,
2724 if (DiagnoseUseOfDecl(Fn, From->getLocStart()))
2727 From = FixOverloadedFunctionReference(From, Found, Fn);
2728 FromType = From->getType();
2731 // If we're converting to an atomic type, first convert to the corresponding
2733 QualType ToAtomicType;
2734 if (const AtomicType *ToAtomic = ToType->getAs<AtomicType>()) {
2735 ToAtomicType = ToType;
2736 ToType = ToAtomic->getValueType();
2739 // Perform the first implicit conversion.
2740 switch (SCS.First) {
2745 case ICK_Lvalue_To_Rvalue: {
2746 assert(From->getObjectKind() != OK_ObjCProperty);
2747 FromType = FromType.getUnqualifiedType();
2748 ExprResult FromRes = DefaultLvalueConversion(From);
2749 assert(!FromRes.isInvalid() && "Can't perform deduced conversion?!");
2750 From = FromRes.get();
2754 case ICK_Array_To_Pointer:
2755 FromType = Context.getArrayDecayedType(FromType);
2756 From = ImpCastExprToType(From, FromType, CK_ArrayToPointerDecay,
2757 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2760 case ICK_Function_To_Pointer:
2761 FromType = Context.getPointerType(FromType);
2762 From = ImpCastExprToType(From, FromType, CK_FunctionToPointerDecay,
2763 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2767 llvm_unreachable("Improper first standard conversion");
2770 // Perform the second implicit conversion
2771 switch (SCS.Second) {
2773 // If both sides are functions (or pointers/references to them), there could
2774 // be incompatible exception declarations.
2775 if (CheckExceptionSpecCompatibility(From, ToType))
2777 // Nothing else to do.
2780 case ICK_NoReturn_Adjustment:
2781 // If both sides are functions (or pointers/references to them), there could
2782 // be incompatible exception declarations.
2783 if (CheckExceptionSpecCompatibility(From, ToType))
2786 From = ImpCastExprToType(From, ToType, CK_NoOp,
2787 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2790 case ICK_Integral_Promotion:
2791 case ICK_Integral_Conversion:
2792 if (ToType->isBooleanType()) {
2793 assert(FromType->castAs<EnumType>()->getDecl()->isFixed() &&
2794 SCS.Second == ICK_Integral_Promotion &&
2795 "only enums with fixed underlying type can promote to bool");
2796 From = ImpCastExprToType(From, ToType, CK_IntegralToBoolean,
2797 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2799 From = ImpCastExprToType(From, ToType, CK_IntegralCast,
2800 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2804 case ICK_Floating_Promotion:
2805 case ICK_Floating_Conversion:
2806 From = ImpCastExprToType(From, ToType, CK_FloatingCast,
2807 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2810 case ICK_Complex_Promotion:
2811 case ICK_Complex_Conversion: {
2812 QualType FromEl = From->getType()->getAs<ComplexType>()->getElementType();
2813 QualType ToEl = ToType->getAs<ComplexType>()->getElementType();
2815 if (FromEl->isRealFloatingType()) {
2816 if (ToEl->isRealFloatingType())
2817 CK = CK_FloatingComplexCast;
2819 CK = CK_FloatingComplexToIntegralComplex;
2820 } else if (ToEl->isRealFloatingType()) {
2821 CK = CK_IntegralComplexToFloatingComplex;
2823 CK = CK_IntegralComplexCast;
2825 From = ImpCastExprToType(From, ToType, CK,
2826 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2830 case ICK_Floating_Integral:
2831 if (ToType->isRealFloatingType())
2832 From = ImpCastExprToType(From, ToType, CK_IntegralToFloating,
2833 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2835 From = ImpCastExprToType(From, ToType, CK_FloatingToIntegral,
2836 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2839 case ICK_Compatible_Conversion:
2840 From = ImpCastExprToType(From, ToType, CK_NoOp,
2841 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2844 case ICK_Writeback_Conversion:
2845 case ICK_Pointer_Conversion: {
2846 if (SCS.IncompatibleObjC && Action != AA_Casting) {
2847 // Diagnose incompatible Objective-C conversions
2848 if (Action == AA_Initializing || Action == AA_Assigning)
2849 Diag(From->getLocStart(),
2850 diag::ext_typecheck_convert_incompatible_pointer)
2851 << ToType << From->getType() << Action
2852 << From->getSourceRange() << 0;
2854 Diag(From->getLocStart(),
2855 diag::ext_typecheck_convert_incompatible_pointer)
2856 << From->getType() << ToType << Action
2857 << From->getSourceRange() << 0;
2859 if (From->getType()->isObjCObjectPointerType() &&
2860 ToType->isObjCObjectPointerType())
2861 EmitRelatedResultTypeNote(From);
2863 else if (getLangOpts().ObjCAutoRefCount &&
2864 !CheckObjCARCUnavailableWeakConversion(ToType,
2866 if (Action == AA_Initializing)
2867 Diag(From->getLocStart(),
2868 diag::err_arc_weak_unavailable_assign);
2870 Diag(From->getLocStart(),
2871 diag::err_arc_convesion_of_weak_unavailable)
2872 << (Action == AA_Casting) << From->getType() << ToType
2873 << From->getSourceRange();
2876 CastKind Kind = CK_Invalid;
2877 CXXCastPath BasePath;
2878 if (CheckPointerConversion(From, ToType, Kind, BasePath, CStyle))
2881 // Make sure we extend blocks if necessary.
2882 // FIXME: doing this here is really ugly.
2883 if (Kind == CK_BlockPointerToObjCPointerCast) {
2884 ExprResult E = From;
2885 (void) PrepareCastToObjCObjectPointer(E);
2888 if (getLangOpts().ObjCAutoRefCount)
2889 CheckObjCARCConversion(SourceRange(), ToType, From, CCK);
2890 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
2895 case ICK_Pointer_Member: {
2896 CastKind Kind = CK_Invalid;
2897 CXXCastPath BasePath;
2898 if (CheckMemberPointerConversion(From, ToType, Kind, BasePath, CStyle))
2900 if (CheckExceptionSpecCompatibility(From, ToType))
2902 From = ImpCastExprToType(From, ToType, Kind, VK_RValue, &BasePath, CCK)
2907 case ICK_Boolean_Conversion:
2908 // Perform half-to-boolean conversion via float.
2909 if (From->getType()->isHalfType()) {
2910 From = ImpCastExprToType(From, Context.FloatTy, CK_FloatingCast).get();
2911 FromType = Context.FloatTy;
2914 From = ImpCastExprToType(From, Context.BoolTy,
2915 ScalarTypeToBooleanCastKind(FromType),
2916 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2919 case ICK_Derived_To_Base: {
2920 CXXCastPath BasePath;
2921 if (CheckDerivedToBaseConversion(From->getType(),
2922 ToType.getNonReferenceType(),
2923 From->getLocStart(),
2924 From->getSourceRange(),
2929 From = ImpCastExprToType(From, ToType.getNonReferenceType(),
2930 CK_DerivedToBase, From->getValueKind(),
2931 &BasePath, CCK).get();
2935 case ICK_Vector_Conversion:
2936 From = ImpCastExprToType(From, ToType, CK_BitCast,
2937 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2940 case ICK_Vector_Splat:
2941 From = ImpCastExprToType(From, ToType, CK_VectorSplat,
2942 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2945 case ICK_Complex_Real:
2946 // Case 1. x -> _Complex y
2947 if (const ComplexType *ToComplex = ToType->getAs<ComplexType>()) {
2948 QualType ElType = ToComplex->getElementType();
2949 bool isFloatingComplex = ElType->isRealFloatingType();
2952 if (Context.hasSameUnqualifiedType(ElType, From->getType())) {
2954 } else if (From->getType()->isRealFloatingType()) {
2955 From = ImpCastExprToType(From, ElType,
2956 isFloatingComplex ? CK_FloatingCast : CK_FloatingToIntegral).get();
2958 assert(From->getType()->isIntegerType());
2959 From = ImpCastExprToType(From, ElType,
2960 isFloatingComplex ? CK_IntegralToFloating : CK_IntegralCast).get();
2963 From = ImpCastExprToType(From, ToType,
2964 isFloatingComplex ? CK_FloatingRealToComplex
2965 : CK_IntegralRealToComplex).get();
2967 // Case 2. _Complex x -> y
2969 const ComplexType *FromComplex = From->getType()->getAs<ComplexType>();
2970 assert(FromComplex);
2972 QualType ElType = FromComplex->getElementType();
2973 bool isFloatingComplex = ElType->isRealFloatingType();
2976 From = ImpCastExprToType(From, ElType,
2977 isFloatingComplex ? CK_FloatingComplexToReal
2978 : CK_IntegralComplexToReal,
2979 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2982 if (Context.hasSameUnqualifiedType(ElType, ToType)) {
2984 } else if (ToType->isRealFloatingType()) {
2985 From = ImpCastExprToType(From, ToType,
2986 isFloatingComplex ? CK_FloatingCast : CK_IntegralToFloating,
2987 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2989 assert(ToType->isIntegerType());
2990 From = ImpCastExprToType(From, ToType,
2991 isFloatingComplex ? CK_FloatingToIntegral : CK_IntegralCast,
2992 VK_RValue, /*BasePath=*/nullptr, CCK).get();
2997 case ICK_Block_Pointer_Conversion: {
2998 From = ImpCastExprToType(From, ToType.getUnqualifiedType(), CK_BitCast,
2999 VK_RValue, /*BasePath=*/nullptr, CCK).get();
3003 case ICK_TransparentUnionConversion: {
3004 ExprResult FromRes = From;
3005 Sema::AssignConvertType ConvTy =
3006 CheckTransparentUnionArgumentConstraints(ToType, FromRes);
3007 if (FromRes.isInvalid())
3009 From = FromRes.get();
3010 assert ((ConvTy == Sema::Compatible) &&
3011 "Improper transparent union conversion");
3016 case ICK_Zero_Event_Conversion:
3017 From = ImpCastExprToType(From, ToType,
3019 From->getValueKind()).get();
3022 case ICK_Lvalue_To_Rvalue:
3023 case ICK_Array_To_Pointer:
3024 case ICK_Function_To_Pointer:
3025 case ICK_Qualification:
3026 case ICK_Num_Conversion_Kinds:
3027 llvm_unreachable("Improper second standard conversion");
3030 switch (SCS.Third) {
3035 case ICK_Qualification: {
3036 // The qualification keeps the category of the inner expression, unless the
3037 // target type isn't a reference.
3038 ExprValueKind VK = ToType->isReferenceType() ?
3039 From->getValueKind() : VK_RValue;
3040 From = ImpCastExprToType(From, ToType.getNonLValueExprType(Context),
3041 CK_NoOp, VK, /*BasePath=*/nullptr, CCK).get();
3043 if (SCS.DeprecatedStringLiteralToCharPtr &&
3044 !getLangOpts().WritableStrings) {
3045 Diag(From->getLocStart(), getLangOpts().CPlusPlus11
3046 ? diag::ext_deprecated_string_literal_conversion
3047 : diag::warn_deprecated_string_literal_conversion)
3048 << ToType.getNonReferenceType();
3055 llvm_unreachable("Improper third standard conversion");
3058 // If this conversion sequence involved a scalar -> atomic conversion, perform
3059 // that conversion now.
3060 if (!ToAtomicType.isNull()) {
3061 assert(Context.hasSameType(
3062 ToAtomicType->castAs<AtomicType>()->getValueType(), From->getType()));
3063 From = ImpCastExprToType(From, ToAtomicType, CK_NonAtomicToAtomic,
3064 VK_RValue, nullptr, CCK).get();
3070 /// \brief Check the completeness of a type in a unary type trait.
3072 /// If the particular type trait requires a complete type, tries to complete
3073 /// it. If completing the type fails, a diagnostic is emitted and false
3074 /// returned. If completing the type succeeds or no completion was required,
3076 static bool CheckUnaryTypeTraitTypeCompleteness(Sema &S, TypeTrait UTT,
3079 // C++0x [meta.unary.prop]p3:
3080 // For all of the class templates X declared in this Clause, instantiating
3081 // that template with a template argument that is a class template
3082 // specialization may result in the implicit instantiation of the template
3083 // argument if and only if the semantics of X require that the argument
3084 // must be a complete type.
3085 // We apply this rule to all the type trait expressions used to implement
3086 // these class templates. We also try to follow any GCC documented behavior
3087 // in these expressions to ensure portability of standard libraries.
3089 default: llvm_unreachable("not a UTT");
3090 // is_complete_type somewhat obviously cannot require a complete type.
3091 case UTT_IsCompleteType:
3094 // These traits are modeled on the type predicates in C++0x
3095 // [meta.unary.cat] and [meta.unary.comp]. They are not specified as
3096 // requiring a complete type, as whether or not they return true cannot be
3097 // impacted by the completeness of the type.
3099 case UTT_IsIntegral:
3100 case UTT_IsFloatingPoint:
3103 case UTT_IsLvalueReference:
3104 case UTT_IsRvalueReference:
3105 case UTT_IsMemberFunctionPointer:
3106 case UTT_IsMemberObjectPointer:
3110 case UTT_IsFunction:
3111 case UTT_IsReference:
3112 case UTT_IsArithmetic:
3113 case UTT_IsFundamental:
3116 case UTT_IsCompound:
3117 case UTT_IsMemberPointer:
3120 // These traits are modeled on type predicates in C++0x [meta.unary.prop]
3121 // which requires some of its traits to have the complete type. However,
3122 // the completeness of the type cannot impact these traits' semantics, and
3123 // so they don't require it. This matches the comments on these traits in
3126 case UTT_IsVolatile:
3128 case UTT_IsUnsigned:
3131 // C++0x [meta.unary.prop] Table 49 requires the following traits to be
3132 // applied to a complete type.
3134 case UTT_IsTriviallyCopyable:
3135 case UTT_IsStandardLayout:
3139 case UTT_IsPolymorphic:
3140 case UTT_IsAbstract:
3141 case UTT_IsInterfaceClass:
3142 case UTT_IsDestructible:
3143 case UTT_IsNothrowDestructible:
3146 // These traits require a complete type.
3150 // These trait expressions are designed to help implement predicates in
3151 // [meta.unary.prop] despite not being named the same. They are specified
3152 // by both GCC and the Embarcadero C++ compiler, and require the complete
3153 // type due to the overarching C++0x type predicates being implemented
3154 // requiring the complete type.
3155 case UTT_HasNothrowAssign:
3156 case UTT_HasNothrowMoveAssign:
3157 case UTT_HasNothrowConstructor:
3158 case UTT_HasNothrowCopy:
3159 case UTT_HasTrivialAssign:
3160 case UTT_HasTrivialMoveAssign:
3161 case UTT_HasTrivialDefaultConstructor:
3162 case UTT_HasTrivialMoveConstructor:
3163 case UTT_HasTrivialCopy:
3164 case UTT_HasTrivialDestructor:
3165 case UTT_HasVirtualDestructor:
3166 // Arrays of unknown bound are expressly allowed.
3167 QualType ElTy = ArgTy;
3168 if (ArgTy->isIncompleteArrayType())
3169 ElTy = S.Context.getAsArrayType(ArgTy)->getElementType();
3171 // The void type is expressly allowed.
3172 if (ElTy->isVoidType())
3175 return !S.RequireCompleteType(
3176 Loc, ElTy, diag::err_incomplete_type_used_in_type_trait_expr);
3180 static bool HasNoThrowOperator(const RecordType *RT, OverloadedOperatorKind Op,
3181 Sema &Self, SourceLocation KeyLoc, ASTContext &C,
3182 bool (CXXRecordDecl::*HasTrivial)() const,
3183 bool (CXXRecordDecl::*HasNonTrivial)() const,
3184 bool (CXXMethodDecl::*IsDesiredOp)() const)
3186 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
3187 if ((RD->*HasTrivial)() && !(RD->*HasNonTrivial)())
3190 DeclarationName Name = C.DeclarationNames.getCXXOperatorName(Op);
3191 DeclarationNameInfo NameInfo(Name, KeyLoc);
3192 LookupResult Res(Self, NameInfo, Sema::LookupOrdinaryName);
3193 if (Self.LookupQualifiedName(Res, RD)) {
3194 bool FoundOperator = false;
3195 Res.suppressDiagnostics();
3196 for (LookupResult::iterator Op = Res.begin(), OpEnd = Res.end();
3197 Op != OpEnd; ++Op) {
3198 if (isa<FunctionTemplateDecl>(*Op))
3201 CXXMethodDecl *Operator = cast<CXXMethodDecl>(*Op);
3202 if((Operator->*IsDesiredOp)()) {
3203 FoundOperator = true;
3204 const FunctionProtoType *CPT =
3205 Operator->getType()->getAs<FunctionProtoType>();
3206 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
3207 if (!CPT || !CPT->isNothrow(C))
3211 return FoundOperator;
3216 static bool EvaluateUnaryTypeTrait(Sema &Self, TypeTrait UTT,
3217 SourceLocation KeyLoc, QualType T) {
3218 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
3220 ASTContext &C = Self.Context;
3222 default: llvm_unreachable("not a UTT");
3223 // Type trait expressions corresponding to the primary type category
3224 // predicates in C++0x [meta.unary.cat].
3226 return T->isVoidType();
3227 case UTT_IsIntegral:
3228 return T->isIntegralType(C);
3229 case UTT_IsFloatingPoint:
3230 return T->isFloatingType();
3232 return T->isArrayType();
3234 return T->isPointerType();
3235 case UTT_IsLvalueReference:
3236 return T->isLValueReferenceType();
3237 case UTT_IsRvalueReference:
3238 return T->isRValueReferenceType();
3239 case UTT_IsMemberFunctionPointer:
3240 return T->isMemberFunctionPointerType();
3241 case UTT_IsMemberObjectPointer:
3242 return T->isMemberDataPointerType();
3244 return T->isEnumeralType();
3246 return T->isUnionType();
3248 return T->isClassType() || T->isStructureType() || T->isInterfaceType();
3249 case UTT_IsFunction:
3250 return T->isFunctionType();
3252 // Type trait expressions which correspond to the convenient composition
3253 // predicates in C++0x [meta.unary.comp].
3254 case UTT_IsReference:
3255 return T->isReferenceType();
3256 case UTT_IsArithmetic:
3257 return T->isArithmeticType() && !T->isEnumeralType();
3258 case UTT_IsFundamental:
3259 return T->isFundamentalType();
3261 return T->isObjectType();
3263 // Note: semantic analysis depends on Objective-C lifetime types to be
3264 // considered scalar types. However, such types do not actually behave
3265 // like scalar types at run time (since they may require retain/release
3266 // operations), so we report them as non-scalar.
3267 if (T->isObjCLifetimeType()) {
3268 switch (T.getObjCLifetime()) {
3269 case Qualifiers::OCL_None:
3270 case Qualifiers::OCL_ExplicitNone:
3273 case Qualifiers::OCL_Strong:
3274 case Qualifiers::OCL_Weak:
3275 case Qualifiers::OCL_Autoreleasing:
3280 return T->isScalarType();
3281 case UTT_IsCompound:
3282 return T->isCompoundType();
3283 case UTT_IsMemberPointer:
3284 return T->isMemberPointerType();
3286 // Type trait expressions which correspond to the type property predicates
3287 // in C++0x [meta.unary.prop].
3289 return T.isConstQualified();
3290 case UTT_IsVolatile:
3291 return T.isVolatileQualified();
3293 return T.isTrivialType(Self.Context);
3294 case UTT_IsTriviallyCopyable:
3295 return T.isTriviallyCopyableType(Self.Context);
3296 case UTT_IsStandardLayout:
3297 return T->isStandardLayoutType();
3299 return T.isPODType(Self.Context);
3301 return T->isLiteralType(Self.Context);
3303 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3304 return !RD->isUnion() && RD->isEmpty();
3306 case UTT_IsPolymorphic:
3307 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3308 return RD->isPolymorphic();
3310 case UTT_IsAbstract:
3311 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3312 return RD->isAbstract();
3314 case UTT_IsInterfaceClass:
3315 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3316 return RD->isInterface();
3319 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3320 return RD->hasAttr<FinalAttr>();
3323 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3324 if (FinalAttr *FA = RD->getAttr<FinalAttr>())
3325 return FA->isSpelledAsSealed();
3328 return T->isSignedIntegerType();
3329 case UTT_IsUnsigned:
3330 return T->isUnsignedIntegerType();
3332 // Type trait expressions which query classes regarding their construction,
3333 // destruction, and copying. Rather than being based directly on the
3334 // related type predicates in the standard, they are specified by both
3335 // GCC[1] and the Embarcadero C++ compiler[2], and Clang implements those
3338 // 1: http://gcc.gnu/.org/onlinedocs/gcc/Type-Traits.html
3339 // 2: http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
3341 // Note that these builtins do not behave as documented in g++: if a class
3342 // has both a trivial and a non-trivial special member of a particular kind,
3343 // they return false! For now, we emulate this behavior.
3344 // FIXME: This appears to be a g++ bug: more complex cases reveal that it
3345 // does not correctly compute triviality in the presence of multiple special
3346 // members of the same kind. Revisit this once the g++ bug is fixed.
3347 case UTT_HasTrivialDefaultConstructor:
3348 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3349 // If __is_pod (type) is true then the trait is true, else if type is
3350 // a cv class or union type (or array thereof) with a trivial default
3351 // constructor ([class.ctor]) then the trait is true, else it is false.
3352 if (T.isPODType(Self.Context))
3354 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
3355 return RD->hasTrivialDefaultConstructor() &&
3356 !RD->hasNonTrivialDefaultConstructor();
3358 case UTT_HasTrivialMoveConstructor:
3359 // This trait is implemented by MSVC 2012 and needed to parse the
3360 // standard library headers. Specifically this is used as the logic
3361 // behind std::is_trivially_move_constructible (20.9.4.3).
3362 if (T.isPODType(Self.Context))
3364 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
3365 return RD->hasTrivialMoveConstructor() && !RD->hasNonTrivialMoveConstructor();
3367 case UTT_HasTrivialCopy:
3368 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3369 // If __is_pod (type) is true or type is a reference type then
3370 // the trait is true, else if type is a cv class or union type
3371 // with a trivial copy constructor ([class.copy]) then the trait
3372 // is true, else it is false.
3373 if (T.isPODType(Self.Context) || T->isReferenceType())
3375 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3376 return RD->hasTrivialCopyConstructor() &&
3377 !RD->hasNonTrivialCopyConstructor();
3379 case UTT_HasTrivialMoveAssign:
3380 // This trait is implemented by MSVC 2012 and needed to parse the
3381 // standard library headers. Specifically it is used as the logic
3382 // behind std::is_trivially_move_assignable (20.9.4.3)
3383 if (T.isPODType(Self.Context))
3385 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
3386 return RD->hasTrivialMoveAssignment() && !RD->hasNonTrivialMoveAssignment();
3388 case UTT_HasTrivialAssign:
3389 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3390 // If type is const qualified or is a reference type then the
3391 // trait is false. Otherwise if __is_pod (type) is true then the
3392 // trait is true, else if type is a cv class or union type with
3393 // a trivial copy assignment ([class.copy]) then the trait is
3394 // true, else it is false.
3395 // Note: the const and reference restrictions are interesting,
3396 // given that const and reference members don't prevent a class
3397 // from having a trivial copy assignment operator (but do cause
3398 // errors if the copy assignment operator is actually used, q.v.
3399 // [class.copy]p12).
3401 if (T.isConstQualified())
3403 if (T.isPODType(Self.Context))
3405 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3406 return RD->hasTrivialCopyAssignment() &&
3407 !RD->hasNonTrivialCopyAssignment();
3409 case UTT_IsDestructible:
3410 case UTT_IsNothrowDestructible:
3411 // FIXME: Implement UTT_IsDestructible and UTT_IsNothrowDestructible.
3412 // For now, let's fall through.
3413 case UTT_HasTrivialDestructor:
3414 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
3415 // If __is_pod (type) is true or type is a reference type
3416 // then the trait is true, else if type is a cv class or union
3417 // type (or array thereof) with a trivial destructor
3418 // ([class.dtor]) then the trait is true, else it is
3420 if (T.isPODType(Self.Context) || T->isReferenceType())
3423 // Objective-C++ ARC: autorelease types don't require destruction.
3424 if (T->isObjCLifetimeType() &&
3425 T.getObjCLifetime() == Qualifiers::OCL_Autoreleasing)
3428 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl())
3429 return RD->hasTrivialDestructor();
3431 // TODO: Propagate nothrowness for implicitly declared special members.
3432 case UTT_HasNothrowAssign:
3433 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3434 // If type is const qualified or is a reference type then the
3435 // trait is false. Otherwise if __has_trivial_assign (type)
3436 // is true then the trait is true, else if type is a cv class
3437 // or union type with copy assignment operators that are known
3438 // not to throw an exception then the trait is true, else it is
3440 if (C.getBaseElementType(T).isConstQualified())
3442 if (T->isReferenceType())
3444 if (T.isPODType(Self.Context) || T->isObjCLifetimeType())
3447 if (const RecordType *RT = T->getAs<RecordType>())
3448 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
3449 &CXXRecordDecl::hasTrivialCopyAssignment,
3450 &CXXRecordDecl::hasNonTrivialCopyAssignment,
3451 &CXXMethodDecl::isCopyAssignmentOperator);
3453 case UTT_HasNothrowMoveAssign:
3454 // This trait is implemented by MSVC 2012 and needed to parse the
3455 // standard library headers. Specifically this is used as the logic
3456 // behind std::is_nothrow_move_assignable (20.9.4.3).
3457 if (T.isPODType(Self.Context))
3460 if (const RecordType *RT = C.getBaseElementType(T)->getAs<RecordType>())
3461 return HasNoThrowOperator(RT, OO_Equal, Self, KeyLoc, C,
3462 &CXXRecordDecl::hasTrivialMoveAssignment,
3463 &CXXRecordDecl::hasNonTrivialMoveAssignment,
3464 &CXXMethodDecl::isMoveAssignmentOperator);
3466 case UTT_HasNothrowCopy:
3467 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3468 // If __has_trivial_copy (type) is true then the trait is true, else
3469 // if type is a cv class or union type with copy constructors that are
3470 // known not to throw an exception then the trait is true, else it is
3472 if (T.isPODType(C) || T->isReferenceType() || T->isObjCLifetimeType())
3474 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl()) {
3475 if (RD->hasTrivialCopyConstructor() &&
3476 !RD->hasNonTrivialCopyConstructor())
3479 bool FoundConstructor = false;
3481 DeclContext::lookup_const_result R = Self.LookupConstructors(RD);
3482 for (DeclContext::lookup_const_iterator Con = R.begin(),
3483 ConEnd = R.end(); Con != ConEnd; ++Con) {
3484 // A template constructor is never a copy constructor.
3485 // FIXME: However, it may actually be selected at the actual overload
3486 // resolution point.
3487 if (isa<FunctionTemplateDecl>(*Con))
3489 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con);
3490 if (Constructor->isCopyConstructor(FoundTQs)) {
3491 FoundConstructor = true;
3492 const FunctionProtoType *CPT
3493 = Constructor->getType()->getAs<FunctionProtoType>();
3494 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
3497 // TODO: check whether evaluating default arguments can throw.
3498 // For now, we'll be conservative and assume that they can throw.
3499 if (!CPT->isNothrow(Self.Context) || CPT->getNumParams() > 1)
3504 return FoundConstructor;
3507 case UTT_HasNothrowConstructor:
3508 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html
3509 // If __has_trivial_constructor (type) is true then the trait is
3510 // true, else if type is a cv class or union type (or array
3511 // thereof) with a default constructor that is known not to
3512 // throw an exception then the trait is true, else it is false.
3513 if (T.isPODType(C) || T->isObjCLifetimeType())
3515 if (CXXRecordDecl *RD = C.getBaseElementType(T)->getAsCXXRecordDecl()) {
3516 if (RD->hasTrivialDefaultConstructor() &&
3517 !RD->hasNonTrivialDefaultConstructor())
3520 bool FoundConstructor = false;
3521 DeclContext::lookup_const_result R = Self.LookupConstructors(RD);
3522 for (DeclContext::lookup_const_iterator Con = R.begin(),
3523 ConEnd = R.end(); Con != ConEnd; ++Con) {
3524 // FIXME: In C++0x, a constructor template can be a default constructor.
3525 if (isa<FunctionTemplateDecl>(*Con))
3527 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con);
3528 if (Constructor->isDefaultConstructor()) {
3529 FoundConstructor = true;
3530 const FunctionProtoType *CPT
3531 = Constructor->getType()->getAs<FunctionProtoType>();
3532 CPT = Self.ResolveExceptionSpec(KeyLoc, CPT);
3535 // FIXME: check whether evaluating default arguments can throw.
3536 // For now, we'll be conservative and assume that they can throw.
3537 if (!CPT->isNothrow(Self.Context) || CPT->getNumParams() > 0)
3541 return FoundConstructor;
3544 case UTT_HasVirtualDestructor:
3545 // http://gcc.gnu.org/onlinedocs/gcc/Type-Traits.html:
3546 // If type is a class type with a virtual destructor ([class.dtor])
3547 // then the trait is true, else it is false.
3548 if (CXXRecordDecl *RD = T->getAsCXXRecordDecl())
3549 if (CXXDestructorDecl *Destructor = Self.LookupDestructor(RD))
3550 return Destructor->isVirtual();
3553 // These type trait expressions are modeled on the specifications for the
3554 // Embarcadero C++0x type trait functions:
3555 // http://docwiki.embarcadero.com/RADStudio/XE/en/Type_Trait_Functions_(C%2B%2B0x)_Index
3556 case UTT_IsCompleteType:
3557 // http://docwiki.embarcadero.com/RADStudio/XE/en/Is_complete_type_(typename_T_):
3558 // Returns True if and only if T is a complete type at the point of the
3560 return !T->isIncompleteType();
3564 /// \brief Determine whether T has a non-trivial Objective-C lifetime in
3566 static bool hasNontrivialObjCLifetime(QualType T) {
3567 switch (T.getObjCLifetime()) {
3568 case Qualifiers::OCL_ExplicitNone:
3571 case Qualifiers::OCL_Strong:
3572 case Qualifiers::OCL_Weak:
3573 case Qualifiers::OCL_Autoreleasing:
3576 case Qualifiers::OCL_None:
3577 return T->isObjCLifetimeType();
3580 llvm_unreachable("Unknown ObjC lifetime qualifier");
3583 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
3584 QualType RhsT, SourceLocation KeyLoc);
3586 static bool evaluateTypeTrait(Sema &S, TypeTrait Kind, SourceLocation KWLoc,
3587 ArrayRef<TypeSourceInfo *> Args,
3588 SourceLocation RParenLoc) {
3589 if (Kind <= UTT_Last)
3590 return EvaluateUnaryTypeTrait(S, Kind, KWLoc, Args[0]->getType());
3592 if (Kind <= BTT_Last)
3593 return EvaluateBinaryTypeTrait(S, Kind, Args[0]->getType(),
3594 Args[1]->getType(), RParenLoc);
3597 case clang::TT_IsConstructible:
3598 case clang::TT_IsNothrowConstructible:
3599 case clang::TT_IsTriviallyConstructible: {
3600 // C++11 [meta.unary.prop]:
3601 // is_trivially_constructible is defined as:
3603 // is_constructible<T, Args...>::value is true and the variable
3604 // definition for is_constructible, as defined below, is known to call
3605 // no operation that is not trivial.
3607 // The predicate condition for a template specialization
3608 // is_constructible<T, Args...> shall be satisfied if and only if the
3609 // following variable definition would be well-formed for some invented
3612 // T t(create<Args>()...);
3613 assert(!Args.empty());
3615 // Precondition: T and all types in the parameter pack Args shall be
3616 // complete types, (possibly cv-qualified) void, or arrays of
3618 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
3619 QualType ArgTy = Args[I]->getType();
3620 if (ArgTy->isVoidType() || ArgTy->isIncompleteArrayType())
3623 if (S.RequireCompleteType(KWLoc, ArgTy,
3624 diag::err_incomplete_type_used_in_type_trait_expr))
3628 // Make sure the first argument is a complete type.
3629 if (Args[0]->getType()->isIncompleteType())
3632 // Make sure the first argument is not an abstract type.
3633 CXXRecordDecl *RD = Args[0]->getType()->getAsCXXRecordDecl();
3634 if (RD && RD->isAbstract())
3637 SmallVector<OpaqueValueExpr, 2> OpaqueArgExprs;
3638 SmallVector<Expr *, 2> ArgExprs;
3639 ArgExprs.reserve(Args.size() - 1);
3640 for (unsigned I = 1, N = Args.size(); I != N; ++I) {
3641 QualType T = Args[I]->getType();
3642 if (T->isObjectType() || T->isFunctionType())
3643 T = S.Context.getRValueReferenceType(T);
3644 OpaqueArgExprs.push_back(
3645 OpaqueValueExpr(Args[I]->getTypeLoc().getLocStart(),
3646 T.getNonLValueExprType(S.Context),
3647 Expr::getValueKindForType(T)));
3648 ArgExprs.push_back(&OpaqueArgExprs.back());
3651 // Perform the initialization in an unevaluated context within a SFINAE
3652 // trap at translation unit scope.
3653 EnterExpressionEvaluationContext Unevaluated(S, Sema::Unevaluated);
3654 Sema::SFINAETrap SFINAE(S, /*AccessCheckingSFINAE=*/true);
3655 Sema::ContextRAII TUContext(S, S.Context.getTranslationUnitDecl());
3656 InitializedEntity To(InitializedEntity::InitializeTemporary(Args[0]));
3657 InitializationKind InitKind(InitializationKind::CreateDirect(KWLoc, KWLoc,
3659 InitializationSequence Init(S, To, InitKind, ArgExprs);
3663 ExprResult Result = Init.Perform(S, To, InitKind, ArgExprs);
3664 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
3667 if (Kind == clang::TT_IsConstructible)
3670 if (Kind == clang::TT_IsNothrowConstructible)
3671 return S.canThrow(Result.get()) == CT_Cannot;
3673 if (Kind == clang::TT_IsTriviallyConstructible) {
3674 // Under Objective-C ARC, if the destination has non-trivial Objective-C
3675 // lifetime, this is a non-trivial construction.
3676 if (S.getLangOpts().ObjCAutoRefCount &&
3677 hasNontrivialObjCLifetime(Args[0]->getType().getNonReferenceType()))
3680 // The initialization succeeded; now make sure there are no non-trivial
3682 return !Result.get()->hasNonTrivialCall(S.Context);
3685 llvm_unreachable("unhandled type trait");
3688 default: llvm_unreachable("not a TT");
3694 ExprResult Sema::BuildTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
3695 ArrayRef<TypeSourceInfo *> Args,
3696 SourceLocation RParenLoc) {
3697 QualType ResultType = Context.getLogicalOperationType();
3699 if (Kind <= UTT_Last && !CheckUnaryTypeTraitTypeCompleteness(
3700 *this, Kind, KWLoc, Args[0]->getType()))
3703 bool Dependent = false;
3704 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
3705 if (Args[I]->getType()->isDependentType()) {
3711 bool Result = false;
3713 Result = evaluateTypeTrait(*this, Kind, KWLoc, Args, RParenLoc);
3715 return TypeTraitExpr::Create(Context, ResultType, KWLoc, Kind, Args,
3719 ExprResult Sema::ActOnTypeTrait(TypeTrait Kind, SourceLocation KWLoc,
3720 ArrayRef<ParsedType> Args,
3721 SourceLocation RParenLoc) {
3722 SmallVector<TypeSourceInfo *, 4> ConvertedArgs;
3723 ConvertedArgs.reserve(Args.size());
3725 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
3726 TypeSourceInfo *TInfo;
3727 QualType T = GetTypeFromParser(Args[I], &TInfo);
3729 TInfo = Context.getTrivialTypeSourceInfo(T, KWLoc);
3731 ConvertedArgs.push_back(TInfo);
3734 return BuildTypeTrait(Kind, KWLoc, ConvertedArgs, RParenLoc);
3737 static bool EvaluateBinaryTypeTrait(Sema &Self, TypeTrait BTT, QualType LhsT,
3738 QualType RhsT, SourceLocation KeyLoc) {
3739 assert(!LhsT->isDependentType() && !RhsT->isDependentType() &&
3740 "Cannot evaluate traits of dependent types");
3743 case BTT_IsBaseOf: {
3744 // C++0x [meta.rel]p2
3745 // Base is a base class of Derived without regard to cv-qualifiers or
3746 // Base and Derived are not unions and name the same class type without
3747 // regard to cv-qualifiers.
3749 const RecordType *lhsRecord = LhsT->getAs<RecordType>();
3750 if (!lhsRecord) return false;
3752 const RecordType *rhsRecord = RhsT->getAs<RecordType>();
3753 if (!rhsRecord) return false;
3755 assert(Self.Context.hasSameUnqualifiedType(LhsT, RhsT)
3756 == (lhsRecord == rhsRecord));
3758 if (lhsRecord == rhsRecord)
3759 return !lhsRecord->getDecl()->isUnion();
3761 // C++0x [meta.rel]p2:
3762 // If Base and Derived are class types and are different types
3763 // (ignoring possible cv-qualifiers) then Derived shall be a
3765 if (Self.RequireCompleteType(KeyLoc, RhsT,
3766 diag::err_incomplete_type_used_in_type_trait_expr))
3769 return cast<CXXRecordDecl>(rhsRecord->getDecl())
3770 ->isDerivedFrom(cast<CXXRecordDecl>(lhsRecord->getDecl()));
3773 return Self.Context.hasSameType(LhsT, RhsT);
3774 case BTT_TypeCompatible:
3775 return Self.Context.typesAreCompatible(LhsT.getUnqualifiedType(),
3776 RhsT.getUnqualifiedType());
3777 case BTT_IsConvertible:
3778 case BTT_IsConvertibleTo: {
3779 // C++0x [meta.rel]p4:
3780 // Given the following function prototype:
3782 // template <class T>
3783 // typename add_rvalue_reference<T>::type create();
3785 // the predicate condition for a template specialization
3786 // is_convertible<From, To> shall be satisfied if and only if
3787 // the return expression in the following code would be
3788 // well-formed, including any implicit conversions to the return
3789 // type of the function:
3792 // return create<From>();
3795 // Access checking is performed as if in a context unrelated to To and
3796 // From. Only the validity of the immediate context of the expression
3797 // of the return-statement (including conversions to the return type)
3800 // We model the initialization as a copy-initialization of a temporary
3801 // of the appropriate type, which for this expression is identical to the
3802 // return statement (since NRVO doesn't apply).
3804 // Functions aren't allowed to return function or array types.
3805 if (RhsT->isFunctionType() || RhsT->isArrayType())
3808 // A return statement in a void function must have void type.
3809 if (RhsT->isVoidType())
3810 return LhsT->isVoidType();
3812 // A function definition requires a complete, non-abstract return type.
3813 if (Self.RequireCompleteType(KeyLoc, RhsT, 0) ||
3814 Self.RequireNonAbstractType(KeyLoc, RhsT, 0))
3817 // Compute the result of add_rvalue_reference.
3818 if (LhsT->isObjectType() || LhsT->isFunctionType())
3819 LhsT = Self.Context.getRValueReferenceType(LhsT);
3821 // Build a fake source and destination for initialization.
3822 InitializedEntity To(InitializedEntity::InitializeTemporary(RhsT));
3823 OpaqueValueExpr From(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
3824 Expr::getValueKindForType(LhsT));
3825 Expr *FromPtr = &From;
3826 InitializationKind Kind(InitializationKind::CreateCopy(KeyLoc,
3829 // Perform the initialization in an unevaluated context within a SFINAE
3830 // trap at translation unit scope.
3831 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated);
3832 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
3833 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
3834 InitializationSequence Init(Self, To, Kind, FromPtr);
3838 ExprResult Result = Init.Perform(Self, To, Kind, FromPtr);
3839 return !Result.isInvalid() && !SFINAE.hasErrorOccurred();
3842 case BTT_IsNothrowAssignable:
3843 case BTT_IsTriviallyAssignable: {
3844 // C++11 [meta.unary.prop]p3:
3845 // is_trivially_assignable is defined as:
3846 // is_assignable<T, U>::value is true and the assignment, as defined by
3847 // is_assignable, is known to call no operation that is not trivial
3849 // is_assignable is defined as:
3850 // The expression declval<T>() = declval<U>() is well-formed when
3851 // treated as an unevaluated operand (Clause 5).
3853 // For both, T and U shall be complete types, (possibly cv-qualified)
3854 // void, or arrays of unknown bound.
3855 if (!LhsT->isVoidType() && !LhsT->isIncompleteArrayType() &&
3856 Self.RequireCompleteType(KeyLoc, LhsT,
3857 diag::err_incomplete_type_used_in_type_trait_expr))
3859 if (!RhsT->isVoidType() && !RhsT->isIncompleteArrayType() &&
3860 Self.RequireCompleteType(KeyLoc, RhsT,
3861 diag::err_incomplete_type_used_in_type_trait_expr))
3864 // cv void is never assignable.
3865 if (LhsT->isVoidType() || RhsT->isVoidType())
3868 // Build expressions that emulate the effect of declval<T>() and
3870 if (LhsT->isObjectType() || LhsT->isFunctionType())
3871 LhsT = Self.Context.getRValueReferenceType(LhsT);
3872 if (RhsT->isObjectType() || RhsT->isFunctionType())
3873 RhsT = Self.Context.getRValueReferenceType(RhsT);
3874 OpaqueValueExpr Lhs(KeyLoc, LhsT.getNonLValueExprType(Self.Context),
3875 Expr::getValueKindForType(LhsT));
3876 OpaqueValueExpr Rhs(KeyLoc, RhsT.getNonLValueExprType(Self.Context),
3877 Expr::getValueKindForType(RhsT));
3879 // Attempt the assignment in an unevaluated context within a SFINAE
3880 // trap at translation unit scope.
3881 EnterExpressionEvaluationContext Unevaluated(Self, Sema::Unevaluated);
3882 Sema::SFINAETrap SFINAE(Self, /*AccessCheckingSFINAE=*/true);
3883 Sema::ContextRAII TUContext(Self, Self.Context.getTranslationUnitDecl());
3884 ExprResult Result = Self.BuildBinOp(/*S=*/nullptr, KeyLoc, BO_Assign, &Lhs,
3886 if (Result.isInvalid() || SFINAE.hasErrorOccurred())
3889 if (BTT == BTT_IsNothrowAssignable)
3890 return Self.canThrow(Result.get()) == CT_Cannot;
3892 if (BTT == BTT_IsTriviallyAssignable) {
3893 // Under Objective-C ARC, if the destination has non-trivial Objective-C
3894 // lifetime, this is a non-trivial assignment.
3895 if (Self.getLangOpts().ObjCAutoRefCount &&
3896 hasNontrivialObjCLifetime(LhsT.getNonReferenceType()))
3899 return !Result.get()->hasNonTrivialCall(Self.Context);
3902 llvm_unreachable("unhandled type trait");
3905 default: llvm_unreachable("not a BTT");
3907 llvm_unreachable("Unknown type trait or not implemented");
3910 ExprResult Sema::ActOnArrayTypeTrait(ArrayTypeTrait ATT,
3911 SourceLocation KWLoc,
3914 SourceLocation RParen) {
3915 TypeSourceInfo *TSInfo;
3916 QualType T = GetTypeFromParser(Ty, &TSInfo);
3918 TSInfo = Context.getTrivialTypeSourceInfo(T);
3920 return BuildArrayTypeTrait(ATT, KWLoc, TSInfo, DimExpr, RParen);
3923 static uint64_t EvaluateArrayTypeTrait(Sema &Self, ArrayTypeTrait ATT,
3924 QualType T, Expr *DimExpr,
3925 SourceLocation KeyLoc) {
3926 assert(!T->isDependentType() && "Cannot evaluate traits of dependent type");
3930 if (T->isArrayType()) {
3932 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
3934 T = AT->getElementType();
3940 case ATT_ArrayExtent: {
3943 if (Self.VerifyIntegerConstantExpression(DimExpr, &Value,
3944 diag::err_dimension_expr_not_constant_integer,
3947 if (Value.isSigned() && Value.isNegative()) {
3948 Self.Diag(KeyLoc, diag::err_dimension_expr_not_constant_integer)
3949 << DimExpr->getSourceRange();
3952 Dim = Value.getLimitedValue();
3954 if (T->isArrayType()) {
3956 bool Matched = false;
3957 while (const ArrayType *AT = Self.Context.getAsArrayType(T)) {
3963 T = AT->getElementType();
3966 if (Matched && T->isArrayType()) {
3967 if (const ConstantArrayType *CAT = Self.Context.getAsConstantArrayType(T))
3968 return CAT->getSize().getLimitedValue();
3974 llvm_unreachable("Unknown type trait or not implemented");
3977 ExprResult Sema::BuildArrayTypeTrait(ArrayTypeTrait ATT,
3978 SourceLocation KWLoc,
3979 TypeSourceInfo *TSInfo,
3981 SourceLocation RParen) {
3982 QualType T = TSInfo->getType();
3984 // FIXME: This should likely be tracked as an APInt to remove any host
3985 // assumptions about the width of size_t on the target.
3987 if (!T->isDependentType())
3988 Value = EvaluateArrayTypeTrait(*this, ATT, T, DimExpr, KWLoc);
3990 // While the specification for these traits from the Embarcadero C++
3991 // compiler's documentation says the return type is 'unsigned int', Clang
3992 // returns 'size_t'. On Windows, the primary platform for the Embarcadero
3993 // compiler, there is no difference. On several other platforms this is an
3994 // important distinction.
3995 return new (Context) ArrayTypeTraitExpr(KWLoc, ATT, TSInfo, Value, DimExpr,
3996 RParen, Context.getSizeType());
3999 ExprResult Sema::ActOnExpressionTrait(ExpressionTrait ET,
4000 SourceLocation KWLoc,
4002 SourceLocation RParen) {
4003 // If error parsing the expression, ignore.
4007 ExprResult Result = BuildExpressionTrait(ET, KWLoc, Queried, RParen);
4012 static bool EvaluateExpressionTrait(ExpressionTrait ET, Expr *E) {
4014 case ET_IsLValueExpr: return E->isLValue();
4015 case ET_IsRValueExpr: return E->isRValue();
4017 llvm_unreachable("Expression trait not covered by switch");
4020 ExprResult Sema::BuildExpressionTrait(ExpressionTrait ET,
4021 SourceLocation KWLoc,
4023 SourceLocation RParen) {
4024 if (Queried->isTypeDependent()) {
4025 // Delay type-checking for type-dependent expressions.
4026 } else if (Queried->getType()->isPlaceholderType()) {
4027 ExprResult PE = CheckPlaceholderExpr(Queried);
4028 if (PE.isInvalid()) return ExprError();
4029 return BuildExpressionTrait(ET, KWLoc, PE.get(), RParen);
4032 bool Value = EvaluateExpressionTrait(ET, Queried);
4034 return new (Context)
4035 ExpressionTraitExpr(KWLoc, ET, Queried, Value, RParen, Context.BoolTy);
4038 QualType Sema::CheckPointerToMemberOperands(ExprResult &LHS, ExprResult &RHS,
4042 assert(!LHS.get()->getType()->isPlaceholderType() &&
4043 !RHS.get()->getType()->isPlaceholderType() &&
4044 "placeholders should have been weeded out by now");
4046 // The LHS undergoes lvalue conversions if this is ->*.
4048 LHS = DefaultLvalueConversion(LHS.get());
4049 if (LHS.isInvalid()) return QualType();
4052 // The RHS always undergoes lvalue conversions.
4053 RHS = DefaultLvalueConversion(RHS.get());
4054 if (RHS.isInvalid()) return QualType();
4056 const char *OpSpelling = isIndirect ? "->*" : ".*";
4058 // The binary operator .* [p3: ->*] binds its second operand, which shall
4059 // be of type "pointer to member of T" (where T is a completely-defined
4060 // class type) [...]
4061 QualType RHSType = RHS.get()->getType();
4062 const MemberPointerType *MemPtr = RHSType->getAs<MemberPointerType>();
4064 Diag(Loc, diag::err_bad_memptr_rhs)
4065 << OpSpelling << RHSType << RHS.get()->getSourceRange();
4069 QualType Class(MemPtr->getClass(), 0);
4071 // Note: C++ [expr.mptr.oper]p2-3 says that the class type into which the
4072 // member pointer points must be completely-defined. However, there is no
4073 // reason for this semantic distinction, and the rule is not enforced by
4074 // other compilers. Therefore, we do not check this property, as it is
4075 // likely to be considered a defect.
4078 // [...] to its first operand, which shall be of class T or of a class of
4079 // which T is an unambiguous and accessible base class. [p3: a pointer to
4081 QualType LHSType = LHS.get()->getType();
4083 if (const PointerType *Ptr = LHSType->getAs<PointerType>())
4084 LHSType = Ptr->getPointeeType();
4086 Diag(Loc, diag::err_bad_memptr_lhs)
4087 << OpSpelling << 1 << LHSType
4088 << FixItHint::CreateReplacement(SourceRange(Loc), ".*");
4093 if (!Context.hasSameUnqualifiedType(Class, LHSType)) {
4094 // If we want to check the hierarchy, we need a complete type.
4095 if (RequireCompleteType(Loc, LHSType, diag::err_bad_memptr_lhs,
4096 OpSpelling, (int)isIndirect)) {
4100 if (!IsDerivedFrom(LHSType, Class)) {
4101 Diag(Loc, diag::err_bad_memptr_lhs) << OpSpelling
4102 << (int)isIndirect << LHS.get()->getType();
4106 CXXCastPath BasePath;
4107 if (CheckDerivedToBaseConversion(LHSType, Class, Loc,
4108 SourceRange(LHS.get()->getLocStart(),
4109 RHS.get()->getLocEnd()),
4113 // Cast LHS to type of use.
4114 QualType UseType = isIndirect ? Context.getPointerType(Class) : Class;
4115 ExprValueKind VK = isIndirect ? VK_RValue : LHS.get()->getValueKind();
4116 LHS = ImpCastExprToType(LHS.get(), UseType, CK_DerivedToBase, VK,
4120 if (isa<CXXScalarValueInitExpr>(RHS.get()->IgnoreParens())) {
4121 // Diagnose use of pointer-to-member type which when used as
4122 // the functional cast in a pointer-to-member expression.
4123 Diag(Loc, diag::err_pointer_to_member_type) << isIndirect;
4128 // The result is an object or a function of the type specified by the
4130 // The cv qualifiers are the union of those in the pointer and the left side,
4131 // in accordance with 5.5p5 and 5.2.5.
4132 QualType Result = MemPtr->getPointeeType();
4133 Result = Context.getCVRQualifiedType(Result, LHSType.getCVRQualifiers());
4135 // C++0x [expr.mptr.oper]p6:
4136 // In a .* expression whose object expression is an rvalue, the program is
4137 // ill-formed if the second operand is a pointer to member function with
4138 // ref-qualifier &. In a ->* expression or in a .* expression whose object
4139 // expression is an lvalue, the program is ill-formed if the second operand
4140 // is a pointer to member function with ref-qualifier &&.
4141 if (const FunctionProtoType *Proto = Result->getAs<FunctionProtoType>()) {
4142 switch (Proto->getRefQualifier()) {
4148 if (!isIndirect && !LHS.get()->Classify(Context).isLValue())
4149 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
4150 << RHSType << 1 << LHS.get()->getSourceRange();
4154 if (isIndirect || !LHS.get()->Classify(Context).isRValue())
4155 Diag(Loc, diag::err_pointer_to_member_oper_value_classify)
4156 << RHSType << 0 << LHS.get()->getSourceRange();
4161 // C++ [expr.mptr.oper]p6:
4162 // The result of a .* expression whose second operand is a pointer
4163 // to a data member is of the same value category as its
4164 // first operand. The result of a .* expression whose second
4165 // operand is a pointer to a member function is a prvalue. The
4166 // result of an ->* expression is an lvalue if its second operand
4167 // is a pointer to data member and a prvalue otherwise.
4168 if (Result->isFunctionType()) {
4170 return Context.BoundMemberTy;
4171 } else if (isIndirect) {
4174 VK = LHS.get()->getValueKind();
4180 /// \brief Try to convert a type to another according to C++0x 5.16p3.
4182 /// This is part of the parameter validation for the ? operator. If either
4183 /// value operand is a class type, the two operands are attempted to be
4184 /// converted to each other. This function does the conversion in one direction.
4185 /// It returns true if the program is ill-formed and has already been diagnosed
4187 static bool TryClassUnification(Sema &Self, Expr *From, Expr *To,
4188 SourceLocation QuestionLoc,
4189 bool &HaveConversion,
4191 HaveConversion = false;
4192 ToType = To->getType();
4194 InitializationKind Kind = InitializationKind::CreateCopy(To->getLocStart(),
4197 // The process for determining whether an operand expression E1 of type T1
4198 // can be converted to match an operand expression E2 of type T2 is defined
4200 // -- If E2 is an lvalue:
4201 bool ToIsLvalue = To->isLValue();
4203 // E1 can be converted to match E2 if E1 can be implicitly converted to
4204 // type "lvalue reference to T2", subject to the constraint that in the
4205 // conversion the reference must bind directly to E1.
4206 QualType T = Self.Context.getLValueReferenceType(ToType);
4207 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
4209 InitializationSequence InitSeq(Self, Entity, Kind, From);
4210 if (InitSeq.isDirectReferenceBinding()) {
4212 HaveConversion = true;
4216 if (InitSeq.isAmbiguous())
4217 return InitSeq.Diagnose(Self, Entity, Kind, From);
4220 // -- If E2 is an rvalue, or if the conversion above cannot be done:
4221 // -- if E1 and E2 have class type, and the underlying class types are
4222 // the same or one is a base class of the other:
4223 QualType FTy = From->getType();
4224 QualType TTy = To->getType();
4225 const RecordType *FRec = FTy->getAs<RecordType>();
4226 const RecordType *TRec = TTy->getAs<RecordType>();
4227 bool FDerivedFromT = FRec && TRec && FRec != TRec &&
4228 Self.IsDerivedFrom(FTy, TTy);
4230 (FRec == TRec || FDerivedFromT || Self.IsDerivedFrom(TTy, FTy))) {
4231 // E1 can be converted to match E2 if the class of T2 is the
4232 // same type as, or a base class of, the class of T1, and
4234 if (FRec == TRec || FDerivedFromT) {
4235 if (TTy.isAtLeastAsQualifiedAs(FTy)) {
4236 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
4237 InitializationSequence InitSeq(Self, Entity, Kind, From);
4239 HaveConversion = true;
4243 if (InitSeq.isAmbiguous())
4244 return InitSeq.Diagnose(Self, Entity, Kind, From);
4251 // -- Otherwise: E1 can be converted to match E2 if E1 can be
4252 // implicitly converted to the type that expression E2 would have
4253 // if E2 were converted to an rvalue (or the type it has, if E2 is
4256 // This actually refers very narrowly to the lvalue-to-rvalue conversion, not
4257 // to the array-to-pointer or function-to-pointer conversions.
4258 if (!TTy->getAs<TagType>())
4259 TTy = TTy.getUnqualifiedType();
4261 InitializedEntity Entity = InitializedEntity::InitializeTemporary(TTy);
4262 InitializationSequence InitSeq(Self, Entity, Kind, From);
4263 HaveConversion = !InitSeq.Failed();
4265 if (InitSeq.isAmbiguous())
4266 return InitSeq.Diagnose(Self, Entity, Kind, From);
4271 /// \brief Try to find a common type for two according to C++0x 5.16p5.
4273 /// This is part of the parameter validation for the ? operator. If either
4274 /// value operand is a class type, overload resolution is used to find a
4275 /// conversion to a common type.
4276 static bool FindConditionalOverload(Sema &Self, ExprResult &LHS, ExprResult &RHS,
4277 SourceLocation QuestionLoc) {
4278 Expr *Args[2] = { LHS.get(), RHS.get() };
4279 OverloadCandidateSet CandidateSet(QuestionLoc,
4280 OverloadCandidateSet::CSK_Operator);
4281 Self.AddBuiltinOperatorCandidates(OO_Conditional, QuestionLoc, Args,
4284 OverloadCandidateSet::iterator Best;
4285 switch (CandidateSet.BestViableFunction(Self, QuestionLoc, Best)) {
4287 // We found a match. Perform the conversions on the arguments and move on.
4289 Self.PerformImplicitConversion(LHS.get(), Best->BuiltinTypes.ParamTypes[0],
4290 Best->Conversions[0], Sema::AA_Converting);
4291 if (LHSRes.isInvalid())
4296 Self.PerformImplicitConversion(RHS.get(), Best->BuiltinTypes.ParamTypes[1],
4297 Best->Conversions[1], Sema::AA_Converting);
4298 if (RHSRes.isInvalid())
4302 Self.MarkFunctionReferenced(QuestionLoc, Best->Function);
4306 case OR_No_Viable_Function:
4308 // Emit a better diagnostic if one of the expressions is a null pointer
4309 // constant and the other is a pointer type. In this case, the user most
4310 // likely forgot to take the address of the other expression.
4311 if (Self.DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
4314 Self.Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
4315 << LHS.get()->getType() << RHS.get()->getType()
4316 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4320 Self.Diag(QuestionLoc, diag::err_conditional_ambiguous_ovl)
4321 << LHS.get()->getType() << RHS.get()->getType()
4322 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4323 // FIXME: Print the possible common types by printing the return types of
4324 // the viable candidates.
4328 llvm_unreachable("Conditional operator has only built-in overloads");
4333 /// \brief Perform an "extended" implicit conversion as returned by
4334 /// TryClassUnification.
4335 static bool ConvertForConditional(Sema &Self, ExprResult &E, QualType T) {
4336 InitializedEntity Entity = InitializedEntity::InitializeTemporary(T);
4337 InitializationKind Kind = InitializationKind::CreateCopy(E.get()->getLocStart(),
4339 Expr *Arg = E.get();
4340 InitializationSequence InitSeq(Self, Entity, Kind, Arg);
4341 ExprResult Result = InitSeq.Perform(Self, Entity, Kind, Arg);
4342 if (Result.isInvalid())
4349 /// \brief Check the operands of ?: under C++ semantics.
4351 /// See C++ [expr.cond]. Note that LHS is never null, even for the GNU x ?: y
4352 /// extension. In this case, LHS == Cond. (But they're not aliases.)
4353 QualType Sema::CXXCheckConditionalOperands(ExprResult &Cond, ExprResult &LHS,
4354 ExprResult &RHS, ExprValueKind &VK,
4356 SourceLocation QuestionLoc) {
4357 // FIXME: Handle C99's complex types, vector types, block pointers and Obj-C++
4358 // interface pointers.
4360 // C++11 [expr.cond]p1
4361 // The first expression is contextually converted to bool.
4362 if (!Cond.get()->isTypeDependent()) {
4363 ExprResult CondRes = CheckCXXBooleanCondition(Cond.get());
4364 if (CondRes.isInvalid())
4373 // Either of the arguments dependent?
4374 if (LHS.get()->isTypeDependent() || RHS.get()->isTypeDependent())
4375 return Context.DependentTy;
4377 // C++11 [expr.cond]p2
4378 // If either the second or the third operand has type (cv) void, ...
4379 QualType LTy = LHS.get()->getType();
4380 QualType RTy = RHS.get()->getType();
4381 bool LVoid = LTy->isVoidType();
4382 bool RVoid = RTy->isVoidType();
4383 if (LVoid || RVoid) {
4384 // ... one of the following shall hold:
4385 // -- The second or the third operand (but not both) is a (possibly
4386 // parenthesized) throw-expression; the result is of the type
4387 // and value category of the other.
4388 bool LThrow = isa<CXXThrowExpr>(LHS.get()->IgnoreParenImpCasts());
4389 bool RThrow = isa<CXXThrowExpr>(RHS.get()->IgnoreParenImpCasts());
4390 if (LThrow != RThrow) {
4391 Expr *NonThrow = LThrow ? RHS.get() : LHS.get();
4392 VK = NonThrow->getValueKind();
4393 // DR (no number yet): the result is a bit-field if the
4394 // non-throw-expression operand is a bit-field.
4395 OK = NonThrow->getObjectKind();
4396 return NonThrow->getType();
4399 // -- Both the second and third operands have type void; the result is of
4400 // type void and is a prvalue.
4402 return Context.VoidTy;
4404 // Neither holds, error.
4405 Diag(QuestionLoc, diag::err_conditional_void_nonvoid)
4406 << (LVoid ? RTy : LTy) << (LVoid ? 0 : 1)
4407 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4413 // C++11 [expr.cond]p3
4414 // Otherwise, if the second and third operand have different types, and
4415 // either has (cv) class type [...] an attempt is made to convert each of
4416 // those operands to the type of the other.
4417 if (!Context.hasSameType(LTy, RTy) &&
4418 (LTy->isRecordType() || RTy->isRecordType())) {
4419 // These return true if a single direction is already ambiguous.
4420 QualType L2RType, R2LType;
4421 bool HaveL2R, HaveR2L;
4422 if (TryClassUnification(*this, LHS.get(), RHS.get(), QuestionLoc, HaveL2R, L2RType))
4424 if (TryClassUnification(*this, RHS.get(), LHS.get(), QuestionLoc, HaveR2L, R2LType))
4427 // If both can be converted, [...] the program is ill-formed.
4428 if (HaveL2R && HaveR2L) {
4429 Diag(QuestionLoc, diag::err_conditional_ambiguous)
4430 << LTy << RTy << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4434 // If exactly one conversion is possible, that conversion is applied to
4435 // the chosen operand and the converted operands are used in place of the
4436 // original operands for the remainder of this section.
4438 if (ConvertForConditional(*this, LHS, L2RType) || LHS.isInvalid())
4440 LTy = LHS.get()->getType();
4441 } else if (HaveR2L) {
4442 if (ConvertForConditional(*this, RHS, R2LType) || RHS.isInvalid())
4444 RTy = RHS.get()->getType();
4448 // C++11 [expr.cond]p3
4449 // if both are glvalues of the same value category and the same type except
4450 // for cv-qualification, an attempt is made to convert each of those
4451 // operands to the type of the other.
4452 ExprValueKind LVK = LHS.get()->getValueKind();
4453 ExprValueKind RVK = RHS.get()->getValueKind();
4454 if (!Context.hasSameType(LTy, RTy) &&
4455 Context.hasSameUnqualifiedType(LTy, RTy) &&
4456 LVK == RVK && LVK != VK_RValue) {
4457 // Since the unqualified types are reference-related and we require the
4458 // result to be as if a reference bound directly, the only conversion
4459 // we can perform is to add cv-qualifiers.
4460 Qualifiers LCVR = Qualifiers::fromCVRMask(LTy.getCVRQualifiers());
4461 Qualifiers RCVR = Qualifiers::fromCVRMask(RTy.getCVRQualifiers());
4462 if (RCVR.isStrictSupersetOf(LCVR)) {
4463 LHS = ImpCastExprToType(LHS.get(), RTy, CK_NoOp, LVK);
4464 LTy = LHS.get()->getType();
4466 else if (LCVR.isStrictSupersetOf(RCVR)) {
4467 RHS = ImpCastExprToType(RHS.get(), LTy, CK_NoOp, RVK);
4468 RTy = RHS.get()->getType();
4472 // C++11 [expr.cond]p4
4473 // If the second and third operands are glvalues of the same value
4474 // category and have the same type, the result is of that type and
4475 // value category and it is a bit-field if the second or the third
4476 // operand is a bit-field, or if both are bit-fields.
4477 // We only extend this to bitfields, not to the crazy other kinds of
4479 bool Same = Context.hasSameType(LTy, RTy);
4480 if (Same && LVK == RVK && LVK != VK_RValue &&
4481 LHS.get()->isOrdinaryOrBitFieldObject() &&
4482 RHS.get()->isOrdinaryOrBitFieldObject()) {
4483 VK = LHS.get()->getValueKind();
4484 if (LHS.get()->getObjectKind() == OK_BitField ||
4485 RHS.get()->getObjectKind() == OK_BitField)
4490 // C++11 [expr.cond]p5
4491 // Otherwise, the result is a prvalue. If the second and third operands
4492 // do not have the same type, and either has (cv) class type, ...
4493 if (!Same && (LTy->isRecordType() || RTy->isRecordType())) {
4494 // ... overload resolution is used to determine the conversions (if any)
4495 // to be applied to the operands. If the overload resolution fails, the
4496 // program is ill-formed.
4497 if (FindConditionalOverload(*this, LHS, RHS, QuestionLoc))
4501 // C++11 [expr.cond]p6
4502 // Lvalue-to-rvalue, array-to-pointer, and function-to-pointer standard
4503 // conversions are performed on the second and third operands.
4504 LHS = DefaultFunctionArrayLvalueConversion(LHS.get());
4505 RHS = DefaultFunctionArrayLvalueConversion(RHS.get());
4506 if (LHS.isInvalid() || RHS.isInvalid())
4508 LTy = LHS.get()->getType();
4509 RTy = RHS.get()->getType();
4511 // After those conversions, one of the following shall hold:
4512 // -- The second and third operands have the same type; the result
4513 // is of that type. If the operands have class type, the result
4514 // is a prvalue temporary of the result type, which is
4515 // copy-initialized from either the second operand or the third
4516 // operand depending on the value of the first operand.
4517 if (Context.getCanonicalType(LTy) == Context.getCanonicalType(RTy)) {
4518 if (LTy->isRecordType()) {
4519 // The operands have class type. Make a temporary copy.
4520 if (RequireNonAbstractType(QuestionLoc, LTy,
4521 diag::err_allocation_of_abstract_type))
4523 InitializedEntity Entity = InitializedEntity::InitializeTemporary(LTy);
4525 ExprResult LHSCopy = PerformCopyInitialization(Entity,
4528 if (LHSCopy.isInvalid())
4531 ExprResult RHSCopy = PerformCopyInitialization(Entity,
4534 if (RHSCopy.isInvalid())
4544 // Extension: conditional operator involving vector types.
4545 if (LTy->isVectorType() || RTy->isVectorType())
4546 return CheckVectorOperands(LHS, RHS, QuestionLoc, /*isCompAssign*/false);
4548 // -- The second and third operands have arithmetic or enumeration type;
4549 // the usual arithmetic conversions are performed to bring them to a
4550 // common type, and the result is of that type.
4551 if (LTy->isArithmeticType() && RTy->isArithmeticType()) {
4552 UsualArithmeticConversions(LHS, RHS);
4553 if (LHS.isInvalid() || RHS.isInvalid())
4555 return LHS.get()->getType();
4558 // -- The second and third operands have pointer type, or one has pointer
4559 // type and the other is a null pointer constant, or both are null
4560 // pointer constants, at least one of which is non-integral; pointer
4561 // conversions and qualification conversions are performed to bring them
4562 // to their composite pointer type. The result is of the composite
4564 // -- The second and third operands have pointer to member type, or one has
4565 // pointer to member type and the other is a null pointer constant;
4566 // pointer to member conversions and qualification conversions are
4567 // performed to bring them to a common type, whose cv-qualification
4568 // shall match the cv-qualification of either the second or the third
4569 // operand. The result is of the common type.
4570 bool NonStandardCompositeType = false;
4571 QualType Composite = FindCompositePointerType(QuestionLoc, LHS, RHS,
4572 isSFINAEContext() ? nullptr
4573 : &NonStandardCompositeType);
4574 if (!Composite.isNull()) {
4575 if (NonStandardCompositeType)
4577 diag::ext_typecheck_cond_incompatible_operands_nonstandard)
4578 << LTy << RTy << Composite
4579 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4584 // Similarly, attempt to find composite type of two objective-c pointers.
4585 Composite = FindCompositeObjCPointerType(LHS, RHS, QuestionLoc);
4586 if (!Composite.isNull())
4589 // Check if we are using a null with a non-pointer type.
4590 if (DiagnoseConditionalForNull(LHS.get(), RHS.get(), QuestionLoc))
4593 Diag(QuestionLoc, diag::err_typecheck_cond_incompatible_operands)
4594 << LHS.get()->getType() << RHS.get()->getType()
4595 << LHS.get()->getSourceRange() << RHS.get()->getSourceRange();
4599 /// \brief Find a merged pointer type and convert the two expressions to it.
4601 /// This finds the composite pointer type (or member pointer type) for @p E1
4602 /// and @p E2 according to C++11 5.9p2. It converts both expressions to this
4603 /// type and returns it.
4604 /// It does not emit diagnostics.
4606 /// \param Loc The location of the operator requiring these two expressions to
4607 /// be converted to the composite pointer type.
4609 /// If \p NonStandardCompositeType is non-NULL, then we are permitted to find
4610 /// a non-standard (but still sane) composite type to which both expressions
4611 /// can be converted. When such a type is chosen, \c *NonStandardCompositeType
4612 /// will be set true.
4613 QualType Sema::FindCompositePointerType(SourceLocation Loc,
4614 Expr *&E1, Expr *&E2,
4615 bool *NonStandardCompositeType) {
4616 if (NonStandardCompositeType)
4617 *NonStandardCompositeType = false;
4619 assert(getLangOpts().CPlusPlus && "This function assumes C++");
4620 QualType T1 = E1->getType(), T2 = E2->getType();
4623 // Pointer conversions and qualification conversions are performed on
4624 // pointer operands to bring them to their composite pointer type. If
4625 // one operand is a null pointer constant, the composite pointer type is
4626 // std::nullptr_t if the other operand is also a null pointer constant or,
4627 // if the other operand is a pointer, the type of the other operand.
4628 if (!T1->isAnyPointerType() && !T1->isMemberPointerType() &&
4629 !T2->isAnyPointerType() && !T2->isMemberPointerType()) {
4630 if (T1->isNullPtrType() &&
4631 E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
4632 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).get();
4635 if (T2->isNullPtrType() &&
4636 E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
4637 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).get();
4643 if (E1->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
4644 if (T2->isMemberPointerType())
4645 E1 = ImpCastExprToType(E1, T2, CK_NullToMemberPointer).get();
4647 E1 = ImpCastExprToType(E1, T2, CK_NullToPointer).get();
4650 if (E2->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) {
4651 if (T1->isMemberPointerType())
4652 E2 = ImpCastExprToType(E2, T1, CK_NullToMemberPointer).get();
4654 E2 = ImpCastExprToType(E2, T1, CK_NullToPointer).get();
4658 // Now both have to be pointers or member pointers.
4659 if ((!T1->isPointerType() && !T1->isMemberPointerType()) ||
4660 (!T2->isPointerType() && !T2->isMemberPointerType()))
4663 // Otherwise, of one of the operands has type "pointer to cv1 void," then
4664 // the other has type "pointer to cv2 T" and the composite pointer type is
4665 // "pointer to cv12 void," where cv12 is the union of cv1 and cv2.
4666 // Otherwise, the composite pointer type is a pointer type similar to the
4667 // type of one of the operands, with a cv-qualification signature that is
4668 // the union of the cv-qualification signatures of the operand types.
4669 // In practice, the first part here is redundant; it's subsumed by the second.
4670 // What we do here is, we build the two possible composite types, and try the
4671 // conversions in both directions. If only one works, or if the two composite
4672 // types are the same, we have succeeded.
4673 // FIXME: extended qualifiers?
4674 typedef SmallVector<unsigned, 4> QualifierVector;
4675 QualifierVector QualifierUnion;
4676 typedef SmallVector<std::pair<const Type *, const Type *>, 4>
4677 ContainingClassVector;
4678 ContainingClassVector MemberOfClass;
4679 QualType Composite1 = Context.getCanonicalType(T1),
4680 Composite2 = Context.getCanonicalType(T2);
4681 unsigned NeedConstBefore = 0;
4683 const PointerType *Ptr1, *Ptr2;
4684 if ((Ptr1 = Composite1->getAs<PointerType>()) &&
4685 (Ptr2 = Composite2->getAs<PointerType>())) {
4686 Composite1 = Ptr1->getPointeeType();
4687 Composite2 = Ptr2->getPointeeType();
4689 // If we're allowed to create a non-standard composite type, keep track
4690 // of where we need to fill in additional 'const' qualifiers.
4691 if (NonStandardCompositeType &&
4692 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
4693 NeedConstBefore = QualifierUnion.size();
4695 QualifierUnion.push_back(
4696 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
4697 MemberOfClass.push_back(std::make_pair(nullptr, nullptr));
4701 const MemberPointerType *MemPtr1, *MemPtr2;
4702 if ((MemPtr1 = Composite1->getAs<MemberPointerType>()) &&
4703 (MemPtr2 = Composite2->getAs<MemberPointerType>())) {
4704 Composite1 = MemPtr1->getPointeeType();
4705 Composite2 = MemPtr2->getPointeeType();
4707 // If we're allowed to create a non-standard composite type, keep track
4708 // of where we need to fill in additional 'const' qualifiers.
4709 if (NonStandardCompositeType &&
4710 Composite1.getCVRQualifiers() != Composite2.getCVRQualifiers())
4711 NeedConstBefore = QualifierUnion.size();
4713 QualifierUnion.push_back(
4714 Composite1.getCVRQualifiers() | Composite2.getCVRQualifiers());
4715 MemberOfClass.push_back(std::make_pair(MemPtr1->getClass(),
4716 MemPtr2->getClass()));
4720 // FIXME: block pointer types?
4722 // Cannot unwrap any more types.
4726 if (NeedConstBefore && NonStandardCompositeType) {
4727 // Extension: Add 'const' to qualifiers that come before the first qualifier
4728 // mismatch, so that our (non-standard!) composite type meets the
4729 // requirements of C++ [conv.qual]p4 bullet 3.
4730 for (unsigned I = 0; I != NeedConstBefore; ++I) {
4731 if ((QualifierUnion[I] & Qualifiers::Const) == 0) {
4732 QualifierUnion[I] = QualifierUnion[I] | Qualifiers::Const;
4733 *NonStandardCompositeType = true;
4738 // Rewrap the composites as pointers or member pointers with the union CVRs.
4739 ContainingClassVector::reverse_iterator MOC
4740 = MemberOfClass.rbegin();
4741 for (QualifierVector::reverse_iterator
4742 I = QualifierUnion.rbegin(),
4743 E = QualifierUnion.rend();
4744 I != E; (void)++I, ++MOC) {
4745 Qualifiers Quals = Qualifiers::fromCVRMask(*I);
4746 if (MOC->first && MOC->second) {
4747 // Rebuild member pointer type
4748 Composite1 = Context.getMemberPointerType(
4749 Context.getQualifiedType(Composite1, Quals),
4751 Composite2 = Context.getMemberPointerType(
4752 Context.getQualifiedType(Composite2, Quals),
4755 // Rebuild pointer type
4757 = Context.getPointerType(Context.getQualifiedType(Composite1, Quals));
4759 = Context.getPointerType(Context.getQualifiedType(Composite2, Quals));
4763 // Try to convert to the first composite pointer type.
4764 InitializedEntity Entity1
4765 = InitializedEntity::InitializeTemporary(Composite1);
4766 InitializationKind Kind
4767 = InitializationKind::CreateCopy(Loc, SourceLocation());
4768 InitializationSequence E1ToC1(*this, Entity1, Kind, E1);
4769 InitializationSequence E2ToC1(*this, Entity1, Kind, E2);
4771 if (E1ToC1 && E2ToC1) {
4772 // Conversion to Composite1 is viable.
4773 if (!Context.hasSameType(Composite1, Composite2)) {
4774 // Composite2 is a different type from Composite1. Check whether
4775 // Composite2 is also viable.
4776 InitializedEntity Entity2
4777 = InitializedEntity::InitializeTemporary(Composite2);
4778 InitializationSequence E1ToC2(*this, Entity2, Kind, E1);
4779 InitializationSequence E2ToC2(*this, Entity2, Kind, E2);
4780 if (E1ToC2 && E2ToC2) {
4781 // Both Composite1 and Composite2 are viable and are different;
4782 // this is an ambiguity.
4787 // Convert E1 to Composite1
4789 = E1ToC1.Perform(*this, Entity1, Kind, E1);
4790 if (E1Result.isInvalid())
4792 E1 = E1Result.getAs<Expr>();
4794 // Convert E2 to Composite1
4796 = E2ToC1.Perform(*this, Entity1, Kind, E2);
4797 if (E2Result.isInvalid())
4799 E2 = E2Result.getAs<Expr>();
4804 // Check whether Composite2 is viable.
4805 InitializedEntity Entity2
4806 = InitializedEntity::InitializeTemporary(Composite2);
4807 InitializationSequence E1ToC2(*this, Entity2, Kind, E1);
4808 InitializationSequence E2ToC2(*this, Entity2, Kind, E2);
4809 if (!E1ToC2 || !E2ToC2)
4812 // Convert E1 to Composite2
4814 = E1ToC2.Perform(*this, Entity2, Kind, E1);
4815 if (E1Result.isInvalid())
4817 E1 = E1Result.getAs<Expr>();
4819 // Convert E2 to Composite2
4821 = E2ToC2.Perform(*this, Entity2, Kind, E2);
4822 if (E2Result.isInvalid())
4824 E2 = E2Result.getAs<Expr>();
4829 ExprResult Sema::MaybeBindToTemporary(Expr *E) {
4833 assert(!isa<CXXBindTemporaryExpr>(E) && "Double-bound temporary?");
4835 // If the result is a glvalue, we shouldn't bind it.
4839 // In ARC, calls that return a retainable type can return retained,
4840 // in which case we have to insert a consuming cast.
4841 if (getLangOpts().ObjCAutoRefCount &&
4842 E->getType()->isObjCRetainableType()) {
4844 bool ReturnsRetained;
4846 // For actual calls, we compute this by examining the type of the
4848 if (CallExpr *Call = dyn_cast<CallExpr>(E)) {
4849 Expr *Callee = Call->getCallee()->IgnoreParens();
4850 QualType T = Callee->getType();
4852 if (T == Context.BoundMemberTy) {
4853 // Handle pointer-to-members.
4854 if (BinaryOperator *BinOp = dyn_cast<BinaryOperator>(Callee))
4855 T = BinOp->getRHS()->getType();
4856 else if (MemberExpr *Mem = dyn_cast<MemberExpr>(Callee))
4857 T = Mem->getMemberDecl()->getType();
4860 if (const PointerType *Ptr = T->getAs<PointerType>())
4861 T = Ptr->getPointeeType();
4862 else if (const BlockPointerType *Ptr = T->getAs<BlockPointerType>())
4863 T = Ptr->getPointeeType();
4864 else if (const MemberPointerType *MemPtr = T->getAs<MemberPointerType>())
4865 T = MemPtr->getPointeeType();
4867 const FunctionType *FTy = T->getAs<FunctionType>();
4868 assert(FTy && "call to value not of function type?");
4869 ReturnsRetained = FTy->getExtInfo().getProducesResult();
4871 // ActOnStmtExpr arranges things so that StmtExprs of retainable
4872 // type always produce a +1 object.
4873 } else if (isa<StmtExpr>(E)) {
4874 ReturnsRetained = true;
4876 // We hit this case with the lambda conversion-to-block optimization;
4877 // we don't want any extra casts here.
4878 } else if (isa<CastExpr>(E) &&
4879 isa<BlockExpr>(cast<CastExpr>(E)->getSubExpr())) {
4882 // For message sends and property references, we try to find an
4883 // actual method. FIXME: we should infer retention by selector in
4884 // cases where we don't have an actual method.
4886 ObjCMethodDecl *D = nullptr;
4887 if (ObjCMessageExpr *Send = dyn_cast<ObjCMessageExpr>(E)) {
4888 D = Send->getMethodDecl();
4889 } else if (ObjCBoxedExpr *BoxedExpr = dyn_cast<ObjCBoxedExpr>(E)) {
4890 D = BoxedExpr->getBoxingMethod();
4891 } else if (ObjCArrayLiteral *ArrayLit = dyn_cast<ObjCArrayLiteral>(E)) {
4892 D = ArrayLit->getArrayWithObjectsMethod();
4893 } else if (ObjCDictionaryLiteral *DictLit
4894 = dyn_cast<ObjCDictionaryLiteral>(E)) {
4895 D = DictLit->getDictWithObjectsMethod();
4898 ReturnsRetained = (D && D->hasAttr<NSReturnsRetainedAttr>());
4900 // Don't do reclaims on performSelector calls; despite their
4901 // return type, the invoked method doesn't necessarily actually
4902 // return an object.
4903 if (!ReturnsRetained &&
4904 D && D->getMethodFamily() == OMF_performSelector)
4908 // Don't reclaim an object of Class type.
4909 if (!ReturnsRetained && E->getType()->isObjCARCImplicitlyUnretainedType())
4912 ExprNeedsCleanups = true;
4914 CastKind ck = (ReturnsRetained ? CK_ARCConsumeObject
4915 : CK_ARCReclaimReturnedObject);
4916 return ImplicitCastExpr::Create(Context, E->getType(), ck, E, nullptr,
4920 if (!getLangOpts().CPlusPlus)
4923 // Search for the base element type (cf. ASTContext::getBaseElementType) with
4924 // a fast path for the common case that the type is directly a RecordType.
4925 const Type *T = Context.getCanonicalType(E->getType().getTypePtr());
4926 const RecordType *RT = nullptr;
4928 switch (T->getTypeClass()) {
4930 RT = cast<RecordType>(T);
4932 case Type::ConstantArray:
4933 case Type::IncompleteArray:
4934 case Type::VariableArray:
4935 case Type::DependentSizedArray:
4936 T = cast<ArrayType>(T)->getElementType().getTypePtr();
4943 // That should be enough to guarantee that this type is complete, if we're
4944 // not processing a decltype expression.
4945 CXXRecordDecl *RD = cast<CXXRecordDecl>(RT->getDecl());
4946 if (RD->isInvalidDecl() || RD->isDependentContext())
4949 bool IsDecltype = ExprEvalContexts.back().IsDecltype;
4950 CXXDestructorDecl *Destructor = IsDecltype ? nullptr : LookupDestructor(RD);
4953 MarkFunctionReferenced(E->getExprLoc(), Destructor);
4954 CheckDestructorAccess(E->getExprLoc(), Destructor,
4955 PDiag(diag::err_access_dtor_temp)
4957 if (DiagnoseUseOfDecl(Destructor, E->getExprLoc()))
4960 // If destructor is trivial, we can avoid the extra copy.
4961 if (Destructor->isTrivial())
4964 // We need a cleanup, but we don't need to remember the temporary.
4965 ExprNeedsCleanups = true;
4968 CXXTemporary *Temp = CXXTemporary::Create(Context, Destructor);
4969 CXXBindTemporaryExpr *Bind = CXXBindTemporaryExpr::Create(Context, Temp, E);
4972 ExprEvalContexts.back().DelayedDecltypeBinds.push_back(Bind);
4978 Sema::MaybeCreateExprWithCleanups(ExprResult SubExpr) {
4979 if (SubExpr.isInvalid())
4982 return MaybeCreateExprWithCleanups(SubExpr.get());
4985 Expr *Sema::MaybeCreateExprWithCleanups(Expr *SubExpr) {
4986 assert(SubExpr && "subexpression can't be null!");
4988 CleanupVarDeclMarking();
4990 unsigned FirstCleanup = ExprEvalContexts.back().NumCleanupObjects;
4991 assert(ExprCleanupObjects.size() >= FirstCleanup);
4992 assert(ExprNeedsCleanups || ExprCleanupObjects.size() == FirstCleanup);
4993 if (!ExprNeedsCleanups)
4996 ArrayRef<ExprWithCleanups::CleanupObject> Cleanups
4997 = llvm::makeArrayRef(ExprCleanupObjects.begin() + FirstCleanup,
4998 ExprCleanupObjects.size() - FirstCleanup);
5000 Expr *E = ExprWithCleanups::Create(Context, SubExpr, Cleanups);
5001 DiscardCleanupsInEvaluationContext();
5006 Stmt *Sema::MaybeCreateStmtWithCleanups(Stmt *SubStmt) {
5007 assert(SubStmt && "sub-statement can't be null!");
5009 CleanupVarDeclMarking();
5011 if (!ExprNeedsCleanups)
5014 // FIXME: In order to attach the temporaries, wrap the statement into
5015 // a StmtExpr; currently this is only used for asm statements.
5016 // This is hacky, either create a new CXXStmtWithTemporaries statement or
5017 // a new AsmStmtWithTemporaries.
5018 CompoundStmt *CompStmt = new (Context) CompoundStmt(Context, SubStmt,
5021 Expr *E = new (Context) StmtExpr(CompStmt, Context.VoidTy, SourceLocation(),
5023 return MaybeCreateExprWithCleanups(E);
5026 /// Process the expression contained within a decltype. For such expressions,
5027 /// certain semantic checks on temporaries are delayed until this point, and
5028 /// are omitted for the 'topmost' call in the decltype expression. If the
5029 /// topmost call bound a temporary, strip that temporary off the expression.
5030 ExprResult Sema::ActOnDecltypeExpression(Expr *E) {
5031 assert(ExprEvalContexts.back().IsDecltype && "not in a decltype expression");
5033 // C++11 [expr.call]p11:
5034 // If a function call is a prvalue of object type,
5035 // -- if the function call is either
5036 // -- the operand of a decltype-specifier, or
5037 // -- the right operand of a comma operator that is the operand of a
5038 // decltype-specifier,
5039 // a temporary object is not introduced for the prvalue.
5041 // Recursively rebuild ParenExprs and comma expressions to strip out the
5042 // outermost CXXBindTemporaryExpr, if any.
5043 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) {
5044 ExprResult SubExpr = ActOnDecltypeExpression(PE->getSubExpr());
5045 if (SubExpr.isInvalid())
5047 if (SubExpr.get() == PE->getSubExpr())
5049 return ActOnParenExpr(PE->getLParen(), PE->getRParen(), SubExpr.get());
5051 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
5052 if (BO->getOpcode() == BO_Comma) {
5053 ExprResult RHS = ActOnDecltypeExpression(BO->getRHS());
5054 if (RHS.isInvalid())
5056 if (RHS.get() == BO->getRHS())
5058 return new (Context) BinaryOperator(
5059 BO->getLHS(), RHS.get(), BO_Comma, BO->getType(), BO->getValueKind(),
5060 BO->getObjectKind(), BO->getOperatorLoc(), BO->isFPContractable());
5064 CXXBindTemporaryExpr *TopBind = dyn_cast<CXXBindTemporaryExpr>(E);
5065 CallExpr *TopCall = TopBind ? dyn_cast<CallExpr>(TopBind->getSubExpr())
5072 // Disable the special decltype handling now.
5073 ExprEvalContexts.back().IsDecltype = false;
5075 // In MS mode, don't perform any extra checking of call return types within a
5076 // decltype expression.
5077 if (getLangOpts().MSVCCompat)
5080 // Perform the semantic checks we delayed until this point.
5081 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeCalls.size();
5083 CallExpr *Call = ExprEvalContexts.back().DelayedDecltypeCalls[I];
5084 if (Call == TopCall)
5087 if (CheckCallReturnType(Call->getCallReturnType(),
5088 Call->getLocStart(),
5089 Call, Call->getDirectCallee()))
5093 // Now all relevant types are complete, check the destructors are accessible
5094 // and non-deleted, and annotate them on the temporaries.
5095 for (unsigned I = 0, N = ExprEvalContexts.back().DelayedDecltypeBinds.size();
5097 CXXBindTemporaryExpr *Bind =
5098 ExprEvalContexts.back().DelayedDecltypeBinds[I];
5099 if (Bind == TopBind)
5102 CXXTemporary *Temp = Bind->getTemporary();
5105 Bind->getType()->getBaseElementTypeUnsafe()->getAsCXXRecordDecl();
5106 CXXDestructorDecl *Destructor = LookupDestructor(RD);
5107 Temp->setDestructor(Destructor);
5109 MarkFunctionReferenced(Bind->getExprLoc(), Destructor);
5110 CheckDestructorAccess(Bind->getExprLoc(), Destructor,
5111 PDiag(diag::err_access_dtor_temp)
5112 << Bind->getType());
5113 if (DiagnoseUseOfDecl(Destructor, Bind->getExprLoc()))
5116 // We need a cleanup, but we don't need to remember the temporary.
5117 ExprNeedsCleanups = true;
5120 // Possibly strip off the top CXXBindTemporaryExpr.
5124 /// Note a set of 'operator->' functions that were used for a member access.
5125 static void noteOperatorArrows(Sema &S,
5126 ArrayRef<FunctionDecl *> OperatorArrows) {
5127 unsigned SkipStart = OperatorArrows.size(), SkipCount = 0;
5128 // FIXME: Make this configurable?
5130 if (OperatorArrows.size() > Limit) {
5131 // Produce Limit-1 normal notes and one 'skipping' note.
5132 SkipStart = (Limit - 1) / 2 + (Limit - 1) % 2;
5133 SkipCount = OperatorArrows.size() - (Limit - 1);
5136 for (unsigned I = 0; I < OperatorArrows.size(); /**/) {
5137 if (I == SkipStart) {
5138 S.Diag(OperatorArrows[I]->getLocation(),
5139 diag::note_operator_arrows_suppressed)
5143 S.Diag(OperatorArrows[I]->getLocation(), diag::note_operator_arrow_here)
5144 << OperatorArrows[I]->getCallResultType();
5151 Sema::ActOnStartCXXMemberReference(Scope *S, Expr *Base, SourceLocation OpLoc,
5152 tok::TokenKind OpKind, ParsedType &ObjectType,
5153 bool &MayBePseudoDestructor) {
5154 // Since this might be a postfix expression, get rid of ParenListExprs.
5155 ExprResult Result = MaybeConvertParenListExprToParenExpr(S, Base);
5156 if (Result.isInvalid()) return ExprError();
5157 Base = Result.get();
5159 Result = CheckPlaceholderExpr(Base);
5160 if (Result.isInvalid()) return ExprError();
5161 Base = Result.get();
5163 QualType BaseType = Base->getType();
5164 MayBePseudoDestructor = false;
5165 if (BaseType->isDependentType()) {
5166 // If we have a pointer to a dependent type and are using the -> operator,
5167 // the object type is the type that the pointer points to. We might still
5168 // have enough information about that type to do something useful.
5169 if (OpKind == tok::arrow)
5170 if (const PointerType *Ptr = BaseType->getAs<PointerType>())
5171 BaseType = Ptr->getPointeeType();
5173 ObjectType = ParsedType::make(BaseType);
5174 MayBePseudoDestructor = true;
5178 // C++ [over.match.oper]p8:
5179 // [...] When operator->returns, the operator-> is applied to the value
5180 // returned, with the original second operand.
5181 if (OpKind == tok::arrow) {
5182 QualType StartingType = BaseType;
5183 bool NoArrowOperatorFound = false;
5184 bool FirstIteration = true;
5185 FunctionDecl *CurFD = dyn_cast<FunctionDecl>(CurContext);
5186 // The set of types we've considered so far.
5187 llvm::SmallPtrSet<CanQualType,8> CTypes;
5188 SmallVector<FunctionDecl*, 8> OperatorArrows;
5189 CTypes.insert(Context.getCanonicalType(BaseType));
5191 while (BaseType->isRecordType()) {
5192 if (OperatorArrows.size() >= getLangOpts().ArrowDepth) {
5193 Diag(OpLoc, diag::err_operator_arrow_depth_exceeded)
5194 << StartingType << getLangOpts().ArrowDepth << Base->getSourceRange();
5195 noteOperatorArrows(*this, OperatorArrows);
5196 Diag(OpLoc, diag::note_operator_arrow_depth)
5197 << getLangOpts().ArrowDepth;
5201 Result = BuildOverloadedArrowExpr(
5203 // When in a template specialization and on the first loop iteration,
5204 // potentially give the default diagnostic (with the fixit in a
5205 // separate note) instead of having the error reported back to here
5206 // and giving a diagnostic with a fixit attached to the error itself.
5207 (FirstIteration && CurFD && CurFD->isFunctionTemplateSpecialization())
5209 : &NoArrowOperatorFound);
5210 if (Result.isInvalid()) {
5211 if (NoArrowOperatorFound) {
5212 if (FirstIteration) {
5213 Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
5214 << BaseType << 1 << Base->getSourceRange()
5215 << FixItHint::CreateReplacement(OpLoc, ".");
5216 OpKind = tok::period;
5219 Diag(OpLoc, diag::err_typecheck_member_reference_arrow)
5220 << BaseType << Base->getSourceRange();
5221 CallExpr *CE = dyn_cast<CallExpr>(Base);
5222 if (Decl *CD = (CE ? CE->getCalleeDecl() : nullptr)) {
5223 Diag(CD->getLocStart(),
5224 diag::note_member_reference_arrow_from_operator_arrow);
5229 Base = Result.get();
5230 if (CXXOperatorCallExpr *OpCall = dyn_cast<CXXOperatorCallExpr>(Base))
5231 OperatorArrows.push_back(OpCall->getDirectCallee());
5232 BaseType = Base->getType();
5233 CanQualType CBaseType = Context.getCanonicalType(BaseType);
5234 if (!CTypes.insert(CBaseType)) {
5235 Diag(OpLoc, diag::err_operator_arrow_circular) << StartingType;
5236 noteOperatorArrows(*this, OperatorArrows);
5239 FirstIteration = false;
5242 if (OpKind == tok::arrow &&
5243 (BaseType->isPointerType() || BaseType->isObjCObjectPointerType()))
5244 BaseType = BaseType->getPointeeType();
5247 // Objective-C properties allow "." access on Objective-C pointer types,
5248 // so adjust the base type to the object type itself.
5249 if (BaseType->isObjCObjectPointerType())
5250 BaseType = BaseType->getPointeeType();
5252 // C++ [basic.lookup.classref]p2:
5253 // [...] If the type of the object expression is of pointer to scalar
5254 // type, the unqualified-id is looked up in the context of the complete
5255 // postfix-expression.
5257 // This also indicates that we could be parsing a pseudo-destructor-name.
5258 // Note that Objective-C class and object types can be pseudo-destructor
5259 // expressions or normal member (ivar or property) access expressions.
5260 if (BaseType->isObjCObjectOrInterfaceType()) {
5261 MayBePseudoDestructor = true;
5262 } else if (!BaseType->isRecordType()) {
5263 ObjectType = ParsedType();
5264 MayBePseudoDestructor = true;
5268 // The object type must be complete (or dependent), or
5269 // C++11 [expr.prim.general]p3:
5270 // Unlike the object expression in other contexts, *this is not required to
5271 // be of complete type for purposes of class member access (5.2.5) outside
5272 // the member function body.
5273 if (!BaseType->isDependentType() &&
5274 !isThisOutsideMemberFunctionBody(BaseType) &&
5275 RequireCompleteType(OpLoc, BaseType, diag::err_incomplete_member_access))
5278 // C++ [basic.lookup.classref]p2:
5279 // If the id-expression in a class member access (5.2.5) is an
5280 // unqualified-id, and the type of the object expression is of a class
5281 // type C (or of pointer to a class type C), the unqualified-id is looked
5282 // up in the scope of class C. [...]
5283 ObjectType = ParsedType::make(BaseType);
5287 ExprResult Sema::DiagnoseDtorReference(SourceLocation NameLoc,
5289 SourceLocation ExpectedLParenLoc = PP.getLocForEndOfToken(NameLoc);
5290 Diag(MemExpr->getLocStart(), diag::err_dtor_expr_without_call)
5291 << isa<CXXPseudoDestructorExpr>(MemExpr)
5292 << FixItHint::CreateInsertion(ExpectedLParenLoc, "()");
5294 return ActOnCallExpr(/*Scope*/ nullptr,
5296 /*LPLoc*/ ExpectedLParenLoc,
5298 /*RPLoc*/ ExpectedLParenLoc);
5301 static bool CheckArrow(Sema& S, QualType& ObjectType, Expr *&Base,
5302 tok::TokenKind& OpKind, SourceLocation OpLoc) {
5303 if (Base->hasPlaceholderType()) {
5304 ExprResult result = S.CheckPlaceholderExpr(Base);
5305 if (result.isInvalid()) return true;
5306 Base = result.get();
5308 ObjectType = Base->getType();
5310 // C++ [expr.pseudo]p2:
5311 // The left-hand side of the dot operator shall be of scalar type. The
5312 // left-hand side of the arrow operator shall be of pointer to scalar type.
5313 // This scalar type is the object type.
5314 // Note that this is rather different from the normal handling for the
5316 if (OpKind == tok::arrow) {
5317 if (const PointerType *Ptr = ObjectType->getAs<PointerType>()) {
5318 ObjectType = Ptr->getPointeeType();
5319 } else if (!Base->isTypeDependent()) {
5320 // The user wrote "p->" when she probably meant "p."; fix it.
5321 S.Diag(OpLoc, diag::err_typecheck_member_reference_suggestion)
5322 << ObjectType << true
5323 << FixItHint::CreateReplacement(OpLoc, ".");
5324 if (S.isSFINAEContext())
5327 OpKind = tok::period;
5334 ExprResult Sema::BuildPseudoDestructorExpr(Expr *Base,
5335 SourceLocation OpLoc,
5336 tok::TokenKind OpKind,
5337 const CXXScopeSpec &SS,
5338 TypeSourceInfo *ScopeTypeInfo,
5339 SourceLocation CCLoc,
5340 SourceLocation TildeLoc,
5341 PseudoDestructorTypeStorage Destructed,
5342 bool HasTrailingLParen) {
5343 TypeSourceInfo *DestructedTypeInfo = Destructed.getTypeSourceInfo();
5345 QualType ObjectType;
5346 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
5349 if (!ObjectType->isDependentType() && !ObjectType->isScalarType() &&
5350 !ObjectType->isVectorType()) {
5351 if (getLangOpts().MSVCCompat && ObjectType->isVoidType())
5352 Diag(OpLoc, diag::ext_pseudo_dtor_on_void) << Base->getSourceRange();
5354 Diag(OpLoc, diag::err_pseudo_dtor_base_not_scalar)
5355 << ObjectType << Base->getSourceRange();
5360 // C++ [expr.pseudo]p2:
5361 // [...] The cv-unqualified versions of the object type and of the type
5362 // designated by the pseudo-destructor-name shall be the same type.
5363 if (DestructedTypeInfo) {
5364 QualType DestructedType = DestructedTypeInfo->getType();
5365 SourceLocation DestructedTypeStart
5366 = DestructedTypeInfo->getTypeLoc().getLocalSourceRange().getBegin();
5367 if (!DestructedType->isDependentType() && !ObjectType->isDependentType()) {
5368 if (!Context.hasSameUnqualifiedType(DestructedType, ObjectType)) {
5369 Diag(DestructedTypeStart, diag::err_pseudo_dtor_type_mismatch)
5370 << ObjectType << DestructedType << Base->getSourceRange()
5371 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
5373 // Recover by setting the destructed type to the object type.
5374 DestructedType = ObjectType;
5375 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType,
5376 DestructedTypeStart);
5377 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
5378 } else if (DestructedType.getObjCLifetime() !=
5379 ObjectType.getObjCLifetime()) {
5381 if (DestructedType.getObjCLifetime() == Qualifiers::OCL_None) {
5382 // Okay: just pretend that the user provided the correctly-qualified
5385 Diag(DestructedTypeStart, diag::err_arc_pseudo_dtor_inconstant_quals)
5386 << ObjectType << DestructedType << Base->getSourceRange()
5387 << DestructedTypeInfo->getTypeLoc().getLocalSourceRange();
5390 // Recover by setting the destructed type to the object type.
5391 DestructedType = ObjectType;
5392 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(ObjectType,
5393 DestructedTypeStart);
5394 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
5399 // C++ [expr.pseudo]p2:
5400 // [...] Furthermore, the two type-names in a pseudo-destructor-name of the
5403 // ::[opt] nested-name-specifier[opt] type-name :: ~ type-name
5405 // shall designate the same scalar type.
5406 if (ScopeTypeInfo) {
5407 QualType ScopeType = ScopeTypeInfo->getType();
5408 if (!ScopeType->isDependentType() && !ObjectType->isDependentType() &&
5409 !Context.hasSameUnqualifiedType(ScopeType, ObjectType)) {
5411 Diag(ScopeTypeInfo->getTypeLoc().getLocalSourceRange().getBegin(),
5412 diag::err_pseudo_dtor_type_mismatch)
5413 << ObjectType << ScopeType << Base->getSourceRange()
5414 << ScopeTypeInfo->getTypeLoc().getLocalSourceRange();
5416 ScopeType = QualType();
5417 ScopeTypeInfo = nullptr;
5422 = new (Context) CXXPseudoDestructorExpr(Context, Base,
5423 OpKind == tok::arrow, OpLoc,
5424 SS.getWithLocInContext(Context),
5430 if (HasTrailingLParen)
5433 return DiagnoseDtorReference(Destructed.getLocation(), Result);
5436 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
5437 SourceLocation OpLoc,
5438 tok::TokenKind OpKind,
5440 UnqualifiedId &FirstTypeName,
5441 SourceLocation CCLoc,
5442 SourceLocation TildeLoc,
5443 UnqualifiedId &SecondTypeName,
5444 bool HasTrailingLParen) {
5445 assert((FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
5446 FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
5447 "Invalid first type name in pseudo-destructor");
5448 assert((SecondTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
5449 SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) &&
5450 "Invalid second type name in pseudo-destructor");
5452 QualType ObjectType;
5453 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
5456 // Compute the object type that we should use for name lookup purposes. Only
5457 // record types and dependent types matter.
5458 ParsedType ObjectTypePtrForLookup;
5460 if (ObjectType->isRecordType())
5461 ObjectTypePtrForLookup = ParsedType::make(ObjectType);
5462 else if (ObjectType->isDependentType())
5463 ObjectTypePtrForLookup = ParsedType::make(Context.DependentTy);
5466 // Convert the name of the type being destructed (following the ~) into a
5467 // type (with source-location information).
5468 QualType DestructedType;
5469 TypeSourceInfo *DestructedTypeInfo = nullptr;
5470 PseudoDestructorTypeStorage Destructed;
5471 if (SecondTypeName.getKind() == UnqualifiedId::IK_Identifier) {
5472 ParsedType T = getTypeName(*SecondTypeName.Identifier,
5473 SecondTypeName.StartLocation,
5474 S, &SS, true, false, ObjectTypePtrForLookup);
5476 ((SS.isSet() && !computeDeclContext(SS, false)) ||
5477 (!SS.isSet() && ObjectType->isDependentType()))) {
5478 // The name of the type being destroyed is a dependent name, and we
5479 // couldn't find anything useful in scope. Just store the identifier and
5480 // it's location, and we'll perform (qualified) name lookup again at
5481 // template instantiation time.
5482 Destructed = PseudoDestructorTypeStorage(SecondTypeName.Identifier,
5483 SecondTypeName.StartLocation);
5485 Diag(SecondTypeName.StartLocation,
5486 diag::err_pseudo_dtor_destructor_non_type)
5487 << SecondTypeName.Identifier << ObjectType;
5488 if (isSFINAEContext())
5491 // Recover by assuming we had the right type all along.
5492 DestructedType = ObjectType;
5494 DestructedType = GetTypeFromParser(T, &DestructedTypeInfo);
5496 // Resolve the template-id to a type.
5497 TemplateIdAnnotation *TemplateId = SecondTypeName.TemplateId;
5498 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
5499 TemplateId->NumArgs);
5500 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
5501 TemplateId->TemplateKWLoc,
5502 TemplateId->Template,
5503 TemplateId->TemplateNameLoc,
5504 TemplateId->LAngleLoc,
5506 TemplateId->RAngleLoc);
5507 if (T.isInvalid() || !T.get()) {
5508 // Recover by assuming we had the right type all along.
5509 DestructedType = ObjectType;
5511 DestructedType = GetTypeFromParser(T.get(), &DestructedTypeInfo);
5514 // If we've performed some kind of recovery, (re-)build the type source
5516 if (!DestructedType.isNull()) {
5517 if (!DestructedTypeInfo)
5518 DestructedTypeInfo = Context.getTrivialTypeSourceInfo(DestructedType,
5519 SecondTypeName.StartLocation);
5520 Destructed = PseudoDestructorTypeStorage(DestructedTypeInfo);
5523 // Convert the name of the scope type (the type prior to '::') into a type.
5524 TypeSourceInfo *ScopeTypeInfo = nullptr;
5526 if (FirstTypeName.getKind() == UnqualifiedId::IK_TemplateId ||
5527 FirstTypeName.Identifier) {
5528 if (FirstTypeName.getKind() == UnqualifiedId::IK_Identifier) {
5529 ParsedType T = getTypeName(*FirstTypeName.Identifier,
5530 FirstTypeName.StartLocation,
5531 S, &SS, true, false, ObjectTypePtrForLookup);
5533 Diag(FirstTypeName.StartLocation,
5534 diag::err_pseudo_dtor_destructor_non_type)
5535 << FirstTypeName.Identifier << ObjectType;
5537 if (isSFINAEContext())
5540 // Just drop this type. It's unnecessary anyway.
5541 ScopeType = QualType();
5543 ScopeType = GetTypeFromParser(T, &ScopeTypeInfo);
5545 // Resolve the template-id to a type.
5546 TemplateIdAnnotation *TemplateId = FirstTypeName.TemplateId;
5547 ASTTemplateArgsPtr TemplateArgsPtr(TemplateId->getTemplateArgs(),
5548 TemplateId->NumArgs);
5549 TypeResult T = ActOnTemplateIdType(TemplateId->SS,
5550 TemplateId->TemplateKWLoc,
5551 TemplateId->Template,
5552 TemplateId->TemplateNameLoc,
5553 TemplateId->LAngleLoc,
5555 TemplateId->RAngleLoc);
5556 if (T.isInvalid() || !T.get()) {
5557 // Recover by dropping this type.
5558 ScopeType = QualType();
5560 ScopeType = GetTypeFromParser(T.get(), &ScopeTypeInfo);
5564 if (!ScopeType.isNull() && !ScopeTypeInfo)
5565 ScopeTypeInfo = Context.getTrivialTypeSourceInfo(ScopeType,
5566 FirstTypeName.StartLocation);
5569 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, SS,
5570 ScopeTypeInfo, CCLoc, TildeLoc,
5571 Destructed, HasTrailingLParen);
5574 ExprResult Sema::ActOnPseudoDestructorExpr(Scope *S, Expr *Base,
5575 SourceLocation OpLoc,
5576 tok::TokenKind OpKind,
5577 SourceLocation TildeLoc,
5579 bool HasTrailingLParen) {
5580 QualType ObjectType;
5581 if (CheckArrow(*this, ObjectType, Base, OpKind, OpLoc))
5584 QualType T = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
5587 DecltypeTypeLoc DecltypeTL = TLB.push<DecltypeTypeLoc>(T);
5588 DecltypeTL.setNameLoc(DS.getTypeSpecTypeLoc());
5589 TypeSourceInfo *DestructedTypeInfo = TLB.getTypeSourceInfo(Context, T);
5590 PseudoDestructorTypeStorage Destructed(DestructedTypeInfo);
5592 return BuildPseudoDestructorExpr(Base, OpLoc, OpKind, CXXScopeSpec(),
5593 nullptr, SourceLocation(), TildeLoc,
5594 Destructed, HasTrailingLParen);
5597 ExprResult Sema::BuildCXXMemberCallExpr(Expr *E, NamedDecl *FoundDecl,
5598 CXXConversionDecl *Method,
5599 bool HadMultipleCandidates) {
5600 if (Method->getParent()->isLambda() &&
5601 Method->getConversionType()->isBlockPointerType()) {
5602 // This is a lambda coversion to block pointer; check if the argument
5605 CastExpr *CE = dyn_cast<CastExpr>(SubE);
5606 if (CE && CE->getCastKind() == CK_NoOp)
5607 SubE = CE->getSubExpr();
5608 SubE = SubE->IgnoreParens();
5609 if (CXXBindTemporaryExpr *BE = dyn_cast<CXXBindTemporaryExpr>(SubE))
5610 SubE = BE->getSubExpr();
5611 if (isa<LambdaExpr>(SubE)) {
5612 // For the conversion to block pointer on a lambda expression, we
5613 // construct a special BlockLiteral instead; this doesn't really make
5614 // a difference in ARC, but outside of ARC the resulting block literal
5615 // follows the normal lifetime rules for block literals instead of being
5617 DiagnosticErrorTrap Trap(Diags);
5618 ExprResult Exp = BuildBlockForLambdaConversion(E->getExprLoc(),
5621 if (Exp.isInvalid())
5622 Diag(E->getExprLoc(), diag::note_lambda_to_block_conv);
5627 ExprResult Exp = PerformObjectArgumentInitialization(E, /*Qualifier=*/nullptr,
5629 if (Exp.isInvalid())
5633 new (Context) MemberExpr(Exp.get(), /*IsArrow=*/false, Method,
5634 SourceLocation(), Context.BoundMemberTy,
5635 VK_RValue, OK_Ordinary);
5636 if (HadMultipleCandidates)
5637 ME->setHadMultipleCandidates(true);
5638 MarkMemberReferenced(ME);
5640 QualType ResultType = Method->getReturnType();
5641 ExprValueKind VK = Expr::getValueKindForType(ResultType);
5642 ResultType = ResultType.getNonLValueExprType(Context);
5644 CXXMemberCallExpr *CE =
5645 new (Context) CXXMemberCallExpr(Context, ME, None, ResultType, VK,
5646 Exp.get()->getLocEnd());
5650 ExprResult Sema::BuildCXXNoexceptExpr(SourceLocation KeyLoc, Expr *Operand,
5651 SourceLocation RParen) {
5652 CanThrowResult CanThrow = canThrow(Operand);
5653 return new (Context)
5654 CXXNoexceptExpr(Context.BoolTy, Operand, CanThrow, KeyLoc, RParen);
5657 ExprResult Sema::ActOnNoexceptExpr(SourceLocation KeyLoc, SourceLocation,
5658 Expr *Operand, SourceLocation RParen) {
5659 return BuildCXXNoexceptExpr(KeyLoc, Operand, RParen);
5662 static bool IsSpecialDiscardedValue(Expr *E) {
5663 // In C++11, discarded-value expressions of a certain form are special,
5664 // according to [expr]p10:
5665 // The lvalue-to-rvalue conversion (4.1) is applied only if the
5666 // expression is an lvalue of volatile-qualified type and it has
5667 // one of the following forms:
5668 E = E->IgnoreParens();
5670 // - id-expression (5.1.1),
5671 if (isa<DeclRefExpr>(E))
5674 // - subscripting (5.2.1),
5675 if (isa<ArraySubscriptExpr>(E))
5678 // - class member access (5.2.5),
5679 if (isa<MemberExpr>(E))
5682 // - indirection (5.3.1),
5683 if (UnaryOperator *UO = dyn_cast<UnaryOperator>(E))
5684 if (UO->getOpcode() == UO_Deref)
5687 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
5688 // - pointer-to-member operation (5.5),
5689 if (BO->isPtrMemOp())
5692 // - comma expression (5.18) where the right operand is one of the above.
5693 if (BO->getOpcode() == BO_Comma)
5694 return IsSpecialDiscardedValue(BO->getRHS());
5697 // - conditional expression (5.16) where both the second and the third
5698 // operands are one of the above, or
5699 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E))
5700 return IsSpecialDiscardedValue(CO->getTrueExpr()) &&
5701 IsSpecialDiscardedValue(CO->getFalseExpr());
5702 // The related edge case of "*x ?: *x".
5703 if (BinaryConditionalOperator *BCO =
5704 dyn_cast<BinaryConditionalOperator>(E)) {
5705 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(BCO->getTrueExpr()))
5706 return IsSpecialDiscardedValue(OVE->getSourceExpr()) &&
5707 IsSpecialDiscardedValue(BCO->getFalseExpr());
5710 // Objective-C++ extensions to the rule.
5711 if (isa<PseudoObjectExpr>(E) || isa<ObjCIvarRefExpr>(E))
5717 /// Perform the conversions required for an expression used in a
5718 /// context that ignores the result.
5719 ExprResult Sema::IgnoredValueConversions(Expr *E) {
5720 if (E->hasPlaceholderType()) {
5721 ExprResult result = CheckPlaceholderExpr(E);
5722 if (result.isInvalid()) return E;
5727 // [Except in specific positions,] an lvalue that does not have
5728 // array type is converted to the value stored in the
5729 // designated object (and is no longer an lvalue).
5730 if (E->isRValue()) {
5731 // In C, function designators (i.e. expressions of function type)
5732 // are r-values, but we still want to do function-to-pointer decay
5733 // on them. This is both technically correct and convenient for
5735 if (!getLangOpts().CPlusPlus && E->getType()->isFunctionType())
5736 return DefaultFunctionArrayConversion(E);
5741 if (getLangOpts().CPlusPlus) {
5742 // The C++11 standard defines the notion of a discarded-value expression;
5743 // normally, we don't need to do anything to handle it, but if it is a
5744 // volatile lvalue with a special form, we perform an lvalue-to-rvalue
5746 if (getLangOpts().CPlusPlus11 && E->isGLValue() &&
5747 E->getType().isVolatileQualified() &&
5748 IsSpecialDiscardedValue(E)) {
5749 ExprResult Res = DefaultLvalueConversion(E);
5750 if (Res.isInvalid())
5757 // GCC seems to also exclude expressions of incomplete enum type.
5758 if (const EnumType *T = E->getType()->getAs<EnumType>()) {
5759 if (!T->getDecl()->isComplete()) {
5760 // FIXME: stupid workaround for a codegen bug!
5761 E = ImpCastExprToType(E, Context.VoidTy, CK_ToVoid).get();
5766 ExprResult Res = DefaultFunctionArrayLvalueConversion(E);
5767 if (Res.isInvalid())
5771 if (!E->getType()->isVoidType())
5772 RequireCompleteType(E->getExprLoc(), E->getType(),
5773 diag::err_incomplete_type);
5777 // If we can unambiguously determine whether Var can never be used
5778 // in a constant expression, return true.
5779 // - if the variable and its initializer are non-dependent, then
5780 // we can unambiguously check if the variable is a constant expression.
5781 // - if the initializer is not value dependent - we can determine whether
5782 // it can be used to initialize a constant expression. If Init can not
5783 // be used to initialize a constant expression we conclude that Var can
5784 // never be a constant expression.
5785 // - FXIME: if the initializer is dependent, we can still do some analysis and
5786 // identify certain cases unambiguously as non-const by using a Visitor:
5787 // - such as those that involve odr-use of a ParmVarDecl, involve a new
5788 // delete, lambda-expr, dynamic-cast, reinterpret-cast etc...
5789 static inline bool VariableCanNeverBeAConstantExpression(VarDecl *Var,
5790 ASTContext &Context) {
5791 if (isa<ParmVarDecl>(Var)) return true;
5792 const VarDecl *DefVD = nullptr;
5794 // If there is no initializer - this can not be a constant expression.
5795 if (!Var->getAnyInitializer(DefVD)) return true;
5797 if (DefVD->isWeak()) return false;
5798 EvaluatedStmt *Eval = DefVD->ensureEvaluatedStmt();
5800 Expr *Init = cast<Expr>(Eval->Value);
5802 if (Var->getType()->isDependentType() || Init->isValueDependent()) {
5803 // FIXME: Teach the constant evaluator to deal with the non-dependent parts
5804 // of value-dependent expressions, and use it here to determine whether the
5805 // initializer is a potential constant expression.
5809 return !IsVariableAConstantExpression(Var, Context);
5812 /// \brief Check if the current lambda has any potential captures
5813 /// that must be captured by any of its enclosing lambdas that are ready to
5814 /// capture. If there is a lambda that can capture a nested
5815 /// potential-capture, go ahead and do so. Also, check to see if any
5816 /// variables are uncaptureable or do not involve an odr-use so do not
5817 /// need to be captured.
5819 static void CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(
5820 Expr *const FE, LambdaScopeInfo *const CurrentLSI, Sema &S) {
5822 assert(!S.isUnevaluatedContext());
5823 assert(S.CurContext->isDependentContext());
5824 assert(CurrentLSI->CallOperator == S.CurContext &&
5825 "The current call operator must be synchronized with Sema's CurContext");
5827 const bool IsFullExprInstantiationDependent = FE->isInstantiationDependent();
5829 ArrayRef<const FunctionScopeInfo *> FunctionScopesArrayRef(
5830 S.FunctionScopes.data(), S.FunctionScopes.size());
5832 // All the potentially captureable variables in the current nested
5833 // lambda (within a generic outer lambda), must be captured by an
5834 // outer lambda that is enclosed within a non-dependent context.
5835 const unsigned NumPotentialCaptures =
5836 CurrentLSI->getNumPotentialVariableCaptures();
5837 for (unsigned I = 0; I != NumPotentialCaptures; ++I) {
5838 Expr *VarExpr = nullptr;
5839 VarDecl *Var = nullptr;
5840 CurrentLSI->getPotentialVariableCapture(I, Var, VarExpr);
5841 // If the variable is clearly identified as non-odr-used and the full
5842 // expression is not instantiation dependent, only then do we not
5843 // need to check enclosing lambda's for speculative captures.
5845 // Even though 'x' is not odr-used, it should be captured.
5847 // const int x = 10;
5848 // auto L = [=](auto a) {
5852 if (CurrentLSI->isVariableExprMarkedAsNonODRUsed(VarExpr) &&
5853 !IsFullExprInstantiationDependent)
5856 // If we have a capture-capable lambda for the variable, go ahead and
5857 // capture the variable in that lambda (and all its enclosing lambdas).
5858 if (const Optional<unsigned> Index =
5859 getStackIndexOfNearestEnclosingCaptureCapableLambda(
5860 FunctionScopesArrayRef, Var, S)) {
5861 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
5862 MarkVarDeclODRUsed(Var, VarExpr->getExprLoc(), S,
5863 &FunctionScopeIndexOfCapturableLambda);
5865 const bool IsVarNeverAConstantExpression =
5866 VariableCanNeverBeAConstantExpression(Var, S.Context);
5867 if (!IsFullExprInstantiationDependent || IsVarNeverAConstantExpression) {
5868 // This full expression is not instantiation dependent or the variable
5869 // can not be used in a constant expression - which means
5870 // this variable must be odr-used here, so diagnose a
5871 // capture violation early, if the variable is un-captureable.
5872 // This is purely for diagnosing errors early. Otherwise, this
5873 // error would get diagnosed when the lambda becomes capture ready.
5874 QualType CaptureType, DeclRefType;
5875 SourceLocation ExprLoc = VarExpr->getExprLoc();
5876 if (S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
5877 /*EllipsisLoc*/ SourceLocation(),
5878 /*BuildAndDiagnose*/false, CaptureType,
5879 DeclRefType, nullptr)) {
5880 // We will never be able to capture this variable, and we need
5881 // to be able to in any and all instantiations, so diagnose it.
5882 S.tryCaptureVariable(Var, ExprLoc, S.TryCapture_Implicit,
5883 /*EllipsisLoc*/ SourceLocation(),
5884 /*BuildAndDiagnose*/true, CaptureType,
5885 DeclRefType, nullptr);
5890 // Check if 'this' needs to be captured.
5891 if (CurrentLSI->hasPotentialThisCapture()) {
5892 // If we have a capture-capable lambda for 'this', go ahead and capture
5893 // 'this' in that lambda (and all its enclosing lambdas).
5894 if (const Optional<unsigned> Index =
5895 getStackIndexOfNearestEnclosingCaptureCapableLambda(
5896 FunctionScopesArrayRef, /*0 is 'this'*/ nullptr, S)) {
5897 const unsigned FunctionScopeIndexOfCapturableLambda = Index.getValue();
5898 S.CheckCXXThisCapture(CurrentLSI->PotentialThisCaptureLocation,
5899 /*Explicit*/ false, /*BuildAndDiagnose*/ true,
5900 &FunctionScopeIndexOfCapturableLambda);
5904 // Reset all the potential captures at the end of each full-expression.
5905 CurrentLSI->clearPotentialCaptures();
5909 ExprResult Sema::ActOnFinishFullExpr(Expr *FE, SourceLocation CC,
5910 bool DiscardedValue,
5912 bool IsLambdaInitCaptureInitializer) {
5913 ExprResult FullExpr = FE;
5915 if (!FullExpr.get())
5918 // If we are an init-expression in a lambdas init-capture, we should not
5919 // diagnose an unexpanded pack now (will be diagnosed once lambda-expr
5920 // containing full-expression is done).
5921 // template<class ... Ts> void test(Ts ... t) {
5922 // test([&a(t)]() { <-- (t) is an init-expr that shouldn't be diagnosed now.
5926 // FIXME: This is a hack. It would be better if we pushed the lambda scope
5927 // when we parse the lambda introducer, and teach capturing (but not
5928 // unexpanded pack detection) to walk over LambdaScopeInfos which don't have a
5929 // corresponding class yet (that is, have LambdaScopeInfo either represent a
5930 // lambda where we've entered the introducer but not the body, or represent a
5931 // lambda where we've entered the body, depending on where the
5932 // parser/instantiation has got to).
5933 if (!IsLambdaInitCaptureInitializer &&
5934 DiagnoseUnexpandedParameterPack(FullExpr.get()))
5937 // Top-level expressions default to 'id' when we're in a debugger.
5938 if (DiscardedValue && getLangOpts().DebuggerCastResultToId &&
5939 FullExpr.get()->getType() == Context.UnknownAnyTy) {
5940 FullExpr = forceUnknownAnyToType(FullExpr.get(), Context.getObjCIdType());
5941 if (FullExpr.isInvalid())
5945 if (DiscardedValue) {
5946 FullExpr = CheckPlaceholderExpr(FullExpr.get());
5947 if (FullExpr.isInvalid())
5950 FullExpr = IgnoredValueConversions(FullExpr.get());
5951 if (FullExpr.isInvalid())
5955 CheckCompletedExpr(FullExpr.get(), CC, IsConstexpr);
5957 // At the end of this full expression (which could be a deeply nested
5958 // lambda), if there is a potential capture within the nested lambda,
5959 // have the outer capture-able lambda try and capture it.
5960 // Consider the following code:
5961 // void f(int, int);
5962 // void f(const int&, double);
5964 // const int x = 10, y = 20;
5965 // auto L = [=](auto a) {
5966 // auto M = [=](auto b) {
5967 // f(x, b); <-- requires x to be captured by L and M
5968 // f(y, a); <-- requires y to be captured by L, but not all Ms
5973 // FIXME: Also consider what happens for something like this that involves
5974 // the gnu-extension statement-expressions or even lambda-init-captures:
5977 // auto L = [&](auto a) {
5978 // +n + ({ 0; a; });
5982 // Here, we see +n, and then the full-expression 0; ends, so we don't
5983 // capture n (and instead remove it from our list of potential captures),
5984 // and then the full-expression +n + ({ 0; }); ends, but it's too late
5985 // for us to see that we need to capture n after all.
5987 LambdaScopeInfo *const CurrentLSI = getCurLambda();
5988 // FIXME: PR 17877 showed that getCurLambda() can return a valid pointer
5989 // even if CurContext is not a lambda call operator. Refer to that Bug Report
5990 // for an example of the code that might cause this asynchrony.
5991 // By ensuring we are in the context of a lambda's call operator
5992 // we can fix the bug (we only need to check whether we need to capture
5993 // if we are within a lambda's body); but per the comments in that
5994 // PR, a proper fix would entail :
5995 // "Alternative suggestion:
5996 // - Add to Sema an integer holding the smallest (outermost) scope
5997 // index that we are *lexically* within, and save/restore/set to
5998 // FunctionScopes.size() in InstantiatingTemplate's
5999 // constructor/destructor.
6000 // - Teach the handful of places that iterate over FunctionScopes to
6001 // stop at the outermost enclosing lexical scope."
6002 const bool IsInLambdaDeclContext = isLambdaCallOperator(CurContext);
6003 if (IsInLambdaDeclContext && CurrentLSI &&
6004 CurrentLSI->hasPotentialCaptures() && !FullExpr.isInvalid())
6005 CheckIfAnyEnclosingLambdasMustCaptureAnyPotentialCaptures(FE, CurrentLSI,
6007 return MaybeCreateExprWithCleanups(FullExpr);
6010 StmtResult Sema::ActOnFinishFullStmt(Stmt *FullStmt) {
6011 if (!FullStmt) return StmtError();
6013 return MaybeCreateStmtWithCleanups(FullStmt);
6016 Sema::IfExistsResult
6017 Sema::CheckMicrosoftIfExistsSymbol(Scope *S,
6019 const DeclarationNameInfo &TargetNameInfo) {
6020 DeclarationName TargetName = TargetNameInfo.getName();
6022 return IER_DoesNotExist;
6024 // If the name itself is dependent, then the result is dependent.
6025 if (TargetName.isDependentName())
6026 return IER_Dependent;
6028 // Do the redeclaration lookup in the current scope.
6029 LookupResult R(*this, TargetNameInfo, Sema::LookupAnyName,
6030 Sema::NotForRedeclaration);
6031 LookupParsedName(R, S, &SS);
6032 R.suppressDiagnostics();
6034 switch (R.getResultKind()) {
6035 case LookupResult::Found:
6036 case LookupResult::FoundOverloaded:
6037 case LookupResult::FoundUnresolvedValue:
6038 case LookupResult::Ambiguous:
6041 case LookupResult::NotFound:
6042 return IER_DoesNotExist;
6044 case LookupResult::NotFoundInCurrentInstantiation:
6045 return IER_Dependent;
6048 llvm_unreachable("Invalid LookupResult Kind!");
6051 Sema::IfExistsResult
6052 Sema::CheckMicrosoftIfExistsSymbol(Scope *S, SourceLocation KeywordLoc,
6053 bool IsIfExists, CXXScopeSpec &SS,
6054 UnqualifiedId &Name) {
6055 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
6057 // Check for unexpanded parameter packs.
6058 SmallVector<UnexpandedParameterPack, 4> Unexpanded;
6059 collectUnexpandedParameterPacks(SS, Unexpanded);
6060 collectUnexpandedParameterPacks(TargetNameInfo, Unexpanded);
6061 if (!Unexpanded.empty()) {
6062 DiagnoseUnexpandedParameterPacks(KeywordLoc,
6063 IsIfExists? UPPC_IfExists
6069 return CheckMicrosoftIfExistsSymbol(S, SS, TargetNameInfo);