1 //===------ SemaDeclCXX.cpp - Semantic Analysis for C++ Declarations ------===//
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 //===----------------------------------------------------------------------===//
10 // This file implements semantic analysis for C++ declarations.
12 //===----------------------------------------------------------------------===//
14 #include "clang/AST/ASTConsumer.h"
15 #include "clang/AST/ASTContext.h"
16 #include "clang/AST/ASTLambda.h"
17 #include "clang/AST/ASTMutationListener.h"
18 #include "clang/AST/CXXInheritance.h"
19 #include "clang/AST/CharUnits.h"
20 #include "clang/AST/EvaluatedExprVisitor.h"
21 #include "clang/AST/ExprCXX.h"
22 #include "clang/AST/RecordLayout.h"
23 #include "clang/AST/RecursiveASTVisitor.h"
24 #include "clang/AST/StmtVisitor.h"
25 #include "clang/AST/TypeLoc.h"
26 #include "clang/AST/TypeOrdering.h"
27 #include "clang/Basic/PartialDiagnostic.h"
28 #include "clang/Basic/TargetInfo.h"
29 #include "clang/Lex/LiteralSupport.h"
30 #include "clang/Lex/Preprocessor.h"
31 #include "clang/Sema/CXXFieldCollector.h"
32 #include "clang/Sema/DeclSpec.h"
33 #include "clang/Sema/Initialization.h"
34 #include "clang/Sema/Lookup.h"
35 #include "clang/Sema/ParsedTemplate.h"
36 #include "clang/Sema/Scope.h"
37 #include "clang/Sema/ScopeInfo.h"
38 #include "clang/Sema/SemaInternal.h"
39 #include "clang/Sema/Template.h"
40 #include "llvm/ADT/STLExtras.h"
41 #include "llvm/ADT/SmallString.h"
42 #include "llvm/ADT/StringExtras.h"
46 using namespace clang;
48 //===----------------------------------------------------------------------===//
49 // CheckDefaultArgumentVisitor
50 //===----------------------------------------------------------------------===//
53 /// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses
54 /// the default argument of a parameter to determine whether it
55 /// contains any ill-formed subexpressions. For example, this will
56 /// diagnose the use of local variables or parameters within the
57 /// default argument expression.
58 class CheckDefaultArgumentVisitor
59 : public StmtVisitor<CheckDefaultArgumentVisitor, bool> {
64 CheckDefaultArgumentVisitor(Expr *defarg, Sema *s)
65 : DefaultArg(defarg), S(s) {}
67 bool VisitExpr(Expr *Node);
68 bool VisitDeclRefExpr(DeclRefExpr *DRE);
69 bool VisitCXXThisExpr(CXXThisExpr *ThisE);
70 bool VisitLambdaExpr(LambdaExpr *Lambda);
71 bool VisitPseudoObjectExpr(PseudoObjectExpr *POE);
74 /// VisitExpr - Visit all of the children of this expression.
75 bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) {
76 bool IsInvalid = false;
77 for (Stmt *SubStmt : Node->children())
78 IsInvalid |= Visit(SubStmt);
82 /// VisitDeclRefExpr - Visit a reference to a declaration, to
83 /// determine whether this declaration can be used in the default
84 /// argument expression.
85 bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) {
86 NamedDecl *Decl = DRE->getDecl();
87 if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) {
88 // C++ [dcl.fct.default]p9
89 // Default arguments are evaluated each time the function is
90 // called. The order of evaluation of function arguments is
91 // unspecified. Consequently, parameters of a function shall not
92 // be used in default argument expressions, even if they are not
93 // evaluated. Parameters of a function declared before a default
94 // argument expression are in scope and can hide namespace and
95 // class member names.
96 return S->Diag(DRE->getLocStart(),
97 diag::err_param_default_argument_references_param)
98 << Param->getDeclName() << DefaultArg->getSourceRange();
99 } else if (VarDecl *VDecl = dyn_cast<VarDecl>(Decl)) {
100 // C++ [dcl.fct.default]p7
101 // Local variables shall not be used in default argument
103 if (VDecl->isLocalVarDecl())
104 return S->Diag(DRE->getLocStart(),
105 diag::err_param_default_argument_references_local)
106 << VDecl->getDeclName() << DefaultArg->getSourceRange();
112 /// VisitCXXThisExpr - Visit a C++ "this" expression.
113 bool CheckDefaultArgumentVisitor::VisitCXXThisExpr(CXXThisExpr *ThisE) {
114 // C++ [dcl.fct.default]p8:
115 // The keyword this shall not be used in a default argument of a
117 return S->Diag(ThisE->getLocStart(),
118 diag::err_param_default_argument_references_this)
119 << ThisE->getSourceRange();
122 bool CheckDefaultArgumentVisitor::VisitPseudoObjectExpr(PseudoObjectExpr *POE) {
123 bool Invalid = false;
124 for (PseudoObjectExpr::semantics_iterator
125 i = POE->semantics_begin(), e = POE->semantics_end(); i != e; ++i) {
128 // Look through bindings.
129 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
130 E = OVE->getSourceExpr();
131 assert(E && "pseudo-object binding without source expression?");
139 bool CheckDefaultArgumentVisitor::VisitLambdaExpr(LambdaExpr *Lambda) {
140 // C++11 [expr.lambda.prim]p13:
141 // A lambda-expression appearing in a default argument shall not
142 // implicitly or explicitly capture any entity.
143 if (Lambda->capture_begin() == Lambda->capture_end())
146 return S->Diag(Lambda->getLocStart(),
147 diag::err_lambda_capture_default_arg);
152 Sema::ImplicitExceptionSpecification::CalledDecl(SourceLocation CallLoc,
153 const CXXMethodDecl *Method) {
154 // If we have an MSAny spec already, don't bother.
155 if (!Method || ComputedEST == EST_MSAny)
158 const FunctionProtoType *Proto
159 = Method->getType()->getAs<FunctionProtoType>();
160 Proto = Self->ResolveExceptionSpec(CallLoc, Proto);
164 ExceptionSpecificationType EST = Proto->getExceptionSpecType();
166 // If we have a throw-all spec at this point, ignore the function.
167 if (ComputedEST == EST_None)
171 // If this function can throw any exceptions, make a note of that.
177 // FIXME: If the call to this decl is using any of its default arguments, we
178 // need to search them for potentially-throwing calls.
179 // If this function has a basic noexcept, it doesn't affect the outcome.
180 case EST_BasicNoexcept:
182 // If we're still at noexcept(true) and there's a nothrow() callee,
183 // change to that specification.
184 case EST_DynamicNone:
185 if (ComputedEST == EST_BasicNoexcept)
186 ComputedEST = EST_DynamicNone;
188 // Check out noexcept specs.
189 case EST_ComputedNoexcept:
191 FunctionProtoType::NoexceptResult NR =
192 Proto->getNoexceptSpec(Self->Context);
193 assert(NR != FunctionProtoType::NR_NoNoexcept &&
194 "Must have noexcept result for EST_ComputedNoexcept.");
195 assert(NR != FunctionProtoType::NR_Dependent &&
196 "Should not generate implicit declarations for dependent cases, "
197 "and don't know how to handle them anyway.");
198 // noexcept(false) -> no spec on the new function
199 if (NR == FunctionProtoType::NR_Throw) {
201 ComputedEST = EST_None;
203 // noexcept(true) won't change anything either.
209 assert(EST == EST_Dynamic && "EST case not considered earlier.");
210 assert(ComputedEST != EST_None &&
211 "Shouldn't collect exceptions when throw-all is guaranteed.");
212 ComputedEST = EST_Dynamic;
213 // Record the exceptions in this function's exception specification.
214 for (const auto &E : Proto->exceptions())
215 if (ExceptionsSeen.insert(Self->Context.getCanonicalType(E)).second)
216 Exceptions.push_back(E);
219 void Sema::ImplicitExceptionSpecification::CalledExpr(Expr *E) {
220 if (!E || ComputedEST == EST_MSAny)
225 // C++0x [except.spec]p14:
226 // [An] implicit exception-specification specifies the type-id T if and
227 // only if T is allowed by the exception-specification of a function directly
228 // invoked by f's implicit definition; f shall allow all exceptions if any
229 // function it directly invokes allows all exceptions, and f shall allow no
230 // exceptions if every function it directly invokes allows no exceptions.
232 // Note in particular that if an implicit exception-specification is generated
233 // for a function containing a throw-expression, that specification can still
234 // be noexcept(true).
236 // Note also that 'directly invoked' is not defined in the standard, and there
237 // is no indication that we should only consider potentially-evaluated calls.
239 // Ultimately we should implement the intent of the standard: the exception
240 // specification should be the set of exceptions which can be thrown by the
241 // implicit definition. For now, we assume that any non-nothrow expression can
242 // throw any exception.
244 if (Self->canThrow(E))
245 ComputedEST = EST_None;
249 Sema::SetParamDefaultArgument(ParmVarDecl *Param, Expr *Arg,
250 SourceLocation EqualLoc) {
251 if (RequireCompleteType(Param->getLocation(), Param->getType(),
252 diag::err_typecheck_decl_incomplete_type)) {
253 Param->setInvalidDecl();
257 // C++ [dcl.fct.default]p5
258 // A default argument expression is implicitly converted (clause
259 // 4) to the parameter type. The default argument expression has
260 // the same semantic constraints as the initializer expression in
261 // a declaration of a variable of the parameter type, using the
262 // copy-initialization semantics (8.5).
263 InitializedEntity Entity = InitializedEntity::InitializeParameter(Context,
265 InitializationKind Kind = InitializationKind::CreateCopy(Param->getLocation(),
267 InitializationSequence InitSeq(*this, Entity, Kind, Arg);
268 ExprResult Result = InitSeq.Perform(*this, Entity, Kind, Arg);
269 if (Result.isInvalid())
271 Arg = Result.getAs<Expr>();
273 CheckCompletedExpr(Arg, EqualLoc);
274 Arg = MaybeCreateExprWithCleanups(Arg);
276 // Okay: add the default argument to the parameter
277 Param->setDefaultArg(Arg);
279 // We have already instantiated this parameter; provide each of the
280 // instantiations with the uninstantiated default argument.
281 UnparsedDefaultArgInstantiationsMap::iterator InstPos
282 = UnparsedDefaultArgInstantiations.find(Param);
283 if (InstPos != UnparsedDefaultArgInstantiations.end()) {
284 for (unsigned I = 0, N = InstPos->second.size(); I != N; ++I)
285 InstPos->second[I]->setUninstantiatedDefaultArg(Arg);
287 // We're done tracking this parameter's instantiations.
288 UnparsedDefaultArgInstantiations.erase(InstPos);
294 /// ActOnParamDefaultArgument - Check whether the default argument
295 /// provided for a function parameter is well-formed. If so, attach it
296 /// to the parameter declaration.
298 Sema::ActOnParamDefaultArgument(Decl *param, SourceLocation EqualLoc,
300 if (!param || !DefaultArg)
303 ParmVarDecl *Param = cast<ParmVarDecl>(param);
304 UnparsedDefaultArgLocs.erase(Param);
306 // Default arguments are only permitted in C++
307 if (!getLangOpts().CPlusPlus) {
308 Diag(EqualLoc, diag::err_param_default_argument)
309 << DefaultArg->getSourceRange();
310 Param->setInvalidDecl();
314 // Check for unexpanded parameter packs.
315 if (DiagnoseUnexpandedParameterPack(DefaultArg, UPPC_DefaultArgument)) {
316 Param->setInvalidDecl();
320 // C++11 [dcl.fct.default]p3
321 // A default argument expression [...] shall not be specified for a
323 if (Param->isParameterPack()) {
324 Diag(EqualLoc, diag::err_param_default_argument_on_parameter_pack)
325 << DefaultArg->getSourceRange();
329 // Check that the default argument is well-formed
330 CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg, this);
331 if (DefaultArgChecker.Visit(DefaultArg)) {
332 Param->setInvalidDecl();
336 SetParamDefaultArgument(Param, DefaultArg, EqualLoc);
339 /// ActOnParamUnparsedDefaultArgument - We've seen a default
340 /// argument for a function parameter, but we can't parse it yet
341 /// because we're inside a class definition. Note that this default
342 /// argument will be parsed later.
343 void Sema::ActOnParamUnparsedDefaultArgument(Decl *param,
344 SourceLocation EqualLoc,
345 SourceLocation ArgLoc) {
349 ParmVarDecl *Param = cast<ParmVarDecl>(param);
350 Param->setUnparsedDefaultArg();
351 UnparsedDefaultArgLocs[Param] = ArgLoc;
354 /// ActOnParamDefaultArgumentError - Parsing or semantic analysis of
355 /// the default argument for the parameter param failed.
356 void Sema::ActOnParamDefaultArgumentError(Decl *param,
357 SourceLocation EqualLoc) {
361 ParmVarDecl *Param = cast<ParmVarDecl>(param);
362 Param->setInvalidDecl();
363 UnparsedDefaultArgLocs.erase(Param);
364 Param->setDefaultArg(new(Context)
365 OpaqueValueExpr(EqualLoc,
366 Param->getType().getNonReferenceType(),
370 /// CheckExtraCXXDefaultArguments - Check for any extra default
371 /// arguments in the declarator, which is not a function declaration
372 /// or definition and therefore is not permitted to have default
373 /// arguments. This routine should be invoked for every declarator
374 /// that is not a function declaration or definition.
375 void Sema::CheckExtraCXXDefaultArguments(Declarator &D) {
376 // C++ [dcl.fct.default]p3
377 // A default argument expression shall be specified only in the
378 // parameter-declaration-clause of a function declaration or in a
379 // template-parameter (14.1). It shall not be specified for a
380 // parameter pack. If it is specified in a
381 // parameter-declaration-clause, it shall not occur within a
382 // declarator or abstract-declarator of a parameter-declaration.
383 bool MightBeFunction = D.isFunctionDeclarationContext();
384 for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) {
385 DeclaratorChunk &chunk = D.getTypeObject(i);
386 if (chunk.Kind == DeclaratorChunk::Function) {
387 if (MightBeFunction) {
388 // This is a function declaration. It can have default arguments, but
389 // keep looking in case its return type is a function type with default
391 MightBeFunction = false;
394 for (unsigned argIdx = 0, e = chunk.Fun.NumParams; argIdx != e;
396 ParmVarDecl *Param = cast<ParmVarDecl>(chunk.Fun.Params[argIdx].Param);
397 if (Param->hasUnparsedDefaultArg()) {
398 std::unique_ptr<CachedTokens> Toks =
399 std::move(chunk.Fun.Params[argIdx].DefaultArgTokens);
401 if (Toks->size() > 1)
402 SR = SourceRange((*Toks)[1].getLocation(),
403 Toks->back().getLocation());
405 SR = UnparsedDefaultArgLocs[Param];
406 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
408 } else if (Param->getDefaultArg()) {
409 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc)
410 << Param->getDefaultArg()->getSourceRange();
411 Param->setDefaultArg(nullptr);
414 } else if (chunk.Kind != DeclaratorChunk::Paren) {
415 MightBeFunction = false;
420 static bool functionDeclHasDefaultArgument(const FunctionDecl *FD) {
421 for (unsigned NumParams = FD->getNumParams(); NumParams > 0; --NumParams) {
422 const ParmVarDecl *PVD = FD->getParamDecl(NumParams-1);
423 if (!PVD->hasDefaultArg())
425 if (!PVD->hasInheritedDefaultArg())
431 /// MergeCXXFunctionDecl - Merge two declarations of the same C++
432 /// function, once we already know that they have the same
433 /// type. Subroutine of MergeFunctionDecl. Returns true if there was an
434 /// error, false otherwise.
435 bool Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old,
437 bool Invalid = false;
439 // The declaration context corresponding to the scope is the semantic
440 // parent, unless this is a local function declaration, in which case
441 // it is that surrounding function.
442 DeclContext *ScopeDC = New->isLocalExternDecl()
443 ? New->getLexicalDeclContext()
444 : New->getDeclContext();
446 // Find the previous declaration for the purpose of default arguments.
447 FunctionDecl *PrevForDefaultArgs = Old;
448 for (/**/; PrevForDefaultArgs;
449 // Don't bother looking back past the latest decl if this is a local
450 // extern declaration; nothing else could work.
451 PrevForDefaultArgs = New->isLocalExternDecl()
453 : PrevForDefaultArgs->getPreviousDecl()) {
454 // Ignore hidden declarations.
455 if (!LookupResult::isVisible(*this, PrevForDefaultArgs))
458 if (S && !isDeclInScope(PrevForDefaultArgs, ScopeDC, S) &&
459 !New->isCXXClassMember()) {
460 // Ignore default arguments of old decl if they are not in
461 // the same scope and this is not an out-of-line definition of
462 // a member function.
466 if (PrevForDefaultArgs->isLocalExternDecl() != New->isLocalExternDecl()) {
467 // If only one of these is a local function declaration, then they are
468 // declared in different scopes, even though isDeclInScope may think
469 // they're in the same scope. (If both are local, the scope check is
470 // sufficent, and if neither is local, then they are in the same scope.)
474 // We found the right previous declaration.
478 // C++ [dcl.fct.default]p4:
479 // For non-template functions, default arguments can be added in
480 // later declarations of a function in the same
481 // scope. Declarations in different scopes have completely
482 // distinct sets of default arguments. That is, declarations in
483 // inner scopes do not acquire default arguments from
484 // declarations in outer scopes, and vice versa. In a given
485 // function declaration, all parameters subsequent to a
486 // parameter with a default argument shall have default
487 // arguments supplied in this or previous declarations. A
488 // default argument shall not be redefined by a later
489 // declaration (not even to the same value).
491 // C++ [dcl.fct.default]p6:
492 // Except for member functions of class templates, the default arguments
493 // in a member function definition that appears outside of the class
494 // definition are added to the set of default arguments provided by the
495 // member function declaration in the class definition.
496 for (unsigned p = 0, NumParams = PrevForDefaultArgs
497 ? PrevForDefaultArgs->getNumParams()
499 p < NumParams; ++p) {
500 ParmVarDecl *OldParam = PrevForDefaultArgs->getParamDecl(p);
501 ParmVarDecl *NewParam = New->getParamDecl(p);
503 bool OldParamHasDfl = OldParam ? OldParam->hasDefaultArg() : false;
504 bool NewParamHasDfl = NewParam->hasDefaultArg();
506 if (OldParamHasDfl && NewParamHasDfl) {
507 unsigned DiagDefaultParamID =
508 diag::err_param_default_argument_redefinition;
510 // MSVC accepts that default parameters be redefined for member functions
511 // of template class. The new default parameter's value is ignored.
513 if (getLangOpts().MicrosoftExt) {
514 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(New);
515 if (MD && MD->getParent()->getDescribedClassTemplate()) {
516 // Merge the old default argument into the new parameter.
517 NewParam->setHasInheritedDefaultArg();
518 if (OldParam->hasUninstantiatedDefaultArg())
519 NewParam->setUninstantiatedDefaultArg(
520 OldParam->getUninstantiatedDefaultArg());
522 NewParam->setDefaultArg(OldParam->getInit());
523 DiagDefaultParamID = diag::ext_param_default_argument_redefinition;
528 // FIXME: If we knew where the '=' was, we could easily provide a fix-it
529 // hint here. Alternatively, we could walk the type-source information
530 // for NewParam to find the last source location in the type... but it
531 // isn't worth the effort right now. This is the kind of test case that
532 // is hard to get right:
534 // void g(int (*fp)(int) = f);
535 // void g(int (*fp)(int) = &f);
536 Diag(NewParam->getLocation(), DiagDefaultParamID)
537 << NewParam->getDefaultArgRange();
539 // Look for the function declaration where the default argument was
540 // actually written, which may be a declaration prior to Old.
541 for (auto Older = PrevForDefaultArgs;
542 OldParam->hasInheritedDefaultArg(); /**/) {
543 Older = Older->getPreviousDecl();
544 OldParam = Older->getParamDecl(p);
547 Diag(OldParam->getLocation(), diag::note_previous_definition)
548 << OldParam->getDefaultArgRange();
549 } else if (OldParamHasDfl) {
550 // Merge the old default argument into the new parameter.
551 // It's important to use getInit() here; getDefaultArg()
552 // strips off any top-level ExprWithCleanups.
553 NewParam->setHasInheritedDefaultArg();
554 if (OldParam->hasUnparsedDefaultArg())
555 NewParam->setUnparsedDefaultArg();
556 else if (OldParam->hasUninstantiatedDefaultArg())
557 NewParam->setUninstantiatedDefaultArg(
558 OldParam->getUninstantiatedDefaultArg());
560 NewParam->setDefaultArg(OldParam->getInit());
561 } else if (NewParamHasDfl) {
562 if (New->getDescribedFunctionTemplate()) {
563 // Paragraph 4, quoted above, only applies to non-template functions.
564 Diag(NewParam->getLocation(),
565 diag::err_param_default_argument_template_redecl)
566 << NewParam->getDefaultArgRange();
567 Diag(PrevForDefaultArgs->getLocation(),
568 diag::note_template_prev_declaration)
570 } else if (New->getTemplateSpecializationKind()
571 != TSK_ImplicitInstantiation &&
572 New->getTemplateSpecializationKind() != TSK_Undeclared) {
573 // C++ [temp.expr.spec]p21:
574 // Default function arguments shall not be specified in a declaration
575 // or a definition for one of the following explicit specializations:
576 // - the explicit specialization of a function template;
577 // - the explicit specialization of a member function template;
578 // - the explicit specialization of a member function of a class
579 // template where the class template specialization to which the
580 // member function specialization belongs is implicitly
582 Diag(NewParam->getLocation(), diag::err_template_spec_default_arg)
583 << (New->getTemplateSpecializationKind() ==TSK_ExplicitSpecialization)
584 << New->getDeclName()
585 << NewParam->getDefaultArgRange();
586 } else if (New->getDeclContext()->isDependentContext()) {
587 // C++ [dcl.fct.default]p6 (DR217):
588 // Default arguments for a member function of a class template shall
589 // be specified on the initial declaration of the member function
590 // within the class template.
592 // Reading the tea leaves a bit in DR217 and its reference to DR205
593 // leads me to the conclusion that one cannot add default function
594 // arguments for an out-of-line definition of a member function of a
597 if (CXXRecordDecl *Record
598 = dyn_cast<CXXRecordDecl>(New->getDeclContext())) {
599 if (Record->getDescribedClassTemplate())
601 else if (isa<ClassTemplatePartialSpecializationDecl>(Record))
607 Diag(NewParam->getLocation(),
608 diag::err_param_default_argument_member_template_redecl)
610 << NewParam->getDefaultArgRange();
615 // DR1344: If a default argument is added outside a class definition and that
616 // default argument makes the function a special member function, the program
617 // is ill-formed. This can only happen for constructors.
618 if (isa<CXXConstructorDecl>(New) &&
619 New->getMinRequiredArguments() < Old->getMinRequiredArguments()) {
620 CXXSpecialMember NewSM = getSpecialMember(cast<CXXMethodDecl>(New)),
621 OldSM = getSpecialMember(cast<CXXMethodDecl>(Old));
622 if (NewSM != OldSM) {
623 ParmVarDecl *NewParam = New->getParamDecl(New->getMinRequiredArguments());
624 assert(NewParam->hasDefaultArg());
625 Diag(NewParam->getLocation(), diag::err_default_arg_makes_ctor_special)
626 << NewParam->getDefaultArgRange() << NewSM;
627 Diag(Old->getLocation(), diag::note_previous_declaration);
631 const FunctionDecl *Def;
632 // C++11 [dcl.constexpr]p1: If any declaration of a function or function
633 // template has a constexpr specifier then all its declarations shall
634 // contain the constexpr specifier.
635 if (New->isConstexpr() != Old->isConstexpr()) {
636 Diag(New->getLocation(), diag::err_constexpr_redecl_mismatch)
637 << New << New->isConstexpr();
638 Diag(Old->getLocation(), diag::note_previous_declaration);
640 } else if (!Old->getMostRecentDecl()->isInlined() && New->isInlined() &&
641 Old->isDefined(Def)) {
642 // C++11 [dcl.fcn.spec]p4:
643 // If the definition of a function appears in a translation unit before its
644 // first declaration as inline, the program is ill-formed.
645 Diag(New->getLocation(), diag::err_inline_decl_follows_def) << New;
646 Diag(Def->getLocation(), diag::note_previous_definition);
650 // C++11 [dcl.fct.default]p4: If a friend declaration specifies a default
651 // argument expression, that declaration shall be a definition and shall be
652 // the only declaration of the function or function template in the
654 if (Old->getFriendObjectKind() == Decl::FOK_Undeclared &&
655 functionDeclHasDefaultArgument(Old)) {
656 Diag(New->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
657 Diag(Old->getLocation(), diag::note_previous_declaration);
665 Sema::ActOnDecompositionDeclarator(Scope *S, Declarator &D,
666 MultiTemplateParamsArg TemplateParamLists) {
667 assert(D.isDecompositionDeclarator());
668 const DecompositionDeclarator &Decomp = D.getDecompositionDeclarator();
670 // The syntax only allows a decomposition declarator as a simple-declaration
671 // or a for-range-declaration, but we parse it in more cases than that.
672 if (!D.mayHaveDecompositionDeclarator()) {
673 Diag(Decomp.getLSquareLoc(), diag::err_decomp_decl_context)
674 << Decomp.getSourceRange();
678 if (!TemplateParamLists.empty()) {
679 // FIXME: There's no rule against this, but there are also no rules that
680 // would actually make it usable, so we reject it for now.
681 Diag(TemplateParamLists.front()->getTemplateLoc(),
682 diag::err_decomp_decl_template);
686 Diag(Decomp.getLSquareLoc(), getLangOpts().CPlusPlus1z
687 ? diag::warn_cxx14_compat_decomp_decl
688 : diag::ext_decomp_decl)
689 << Decomp.getSourceRange();
691 // The semantic context is always just the current context.
692 DeclContext *const DC = CurContext;
694 // C++1z [dcl.dcl]/8:
695 // The decl-specifier-seq shall contain only the type-specifier auto
696 // and cv-qualifiers.
697 auto &DS = D.getDeclSpec();
699 SmallVector<StringRef, 8> BadSpecifiers;
700 SmallVector<SourceLocation, 8> BadSpecifierLocs;
701 if (auto SCS = DS.getStorageClassSpec()) {
702 BadSpecifiers.push_back(DeclSpec::getSpecifierName(SCS));
703 BadSpecifierLocs.push_back(DS.getStorageClassSpecLoc());
705 if (auto TSCS = DS.getThreadStorageClassSpec()) {
706 BadSpecifiers.push_back(DeclSpec::getSpecifierName(TSCS));
707 BadSpecifierLocs.push_back(DS.getThreadStorageClassSpecLoc());
709 if (DS.isConstexprSpecified()) {
710 BadSpecifiers.push_back("constexpr");
711 BadSpecifierLocs.push_back(DS.getConstexprSpecLoc());
713 if (DS.isInlineSpecified()) {
714 BadSpecifiers.push_back("inline");
715 BadSpecifierLocs.push_back(DS.getInlineSpecLoc());
717 if (!BadSpecifiers.empty()) {
718 auto &&Err = Diag(BadSpecifierLocs.front(), diag::err_decomp_decl_spec);
719 Err << (int)BadSpecifiers.size()
720 << llvm::join(BadSpecifiers.begin(), BadSpecifiers.end(), " ");
721 // Don't add FixItHints to remove the specifiers; we do still respect
722 // them when building the underlying variable.
723 for (auto Loc : BadSpecifierLocs)
724 Err << SourceRange(Loc, Loc);
726 // We can't recover from it being declared as a typedef.
727 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
731 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
732 QualType R = TInfo->getType();
734 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
735 UPPC_DeclarationType))
738 // The syntax only allows a single ref-qualifier prior to the decomposition
739 // declarator. No other declarator chunks are permitted. Also check the type
741 if (DS.getTypeSpecType() != DeclSpec::TST_auto ||
742 D.hasGroupingParens() || D.getNumTypeObjects() > 1 ||
743 (D.getNumTypeObjects() == 1 &&
744 D.getTypeObject(0).Kind != DeclaratorChunk::Reference)) {
745 Diag(Decomp.getLSquareLoc(),
746 (D.hasGroupingParens() ||
747 (D.getNumTypeObjects() &&
748 D.getTypeObject(0).Kind == DeclaratorChunk::Paren))
749 ? diag::err_decomp_decl_parens
750 : diag::err_decomp_decl_type)
753 // In most cases, there's no actual problem with an explicitly-specified
754 // type, but a function type won't work here, and ActOnVariableDeclarator
755 // shouldn't be called for such a type.
756 if (R->isFunctionType())
760 // Build the BindingDecls.
761 SmallVector<BindingDecl*, 8> Bindings;
763 // Build the BindingDecls.
764 for (auto &B : D.getDecompositionDeclarator().bindings()) {
765 // Check for name conflicts.
766 DeclarationNameInfo NameInfo(B.Name, B.NameLoc);
767 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
769 LookupName(Previous, S,
770 /*CreateBuiltins*/DC->getRedeclContext()->isTranslationUnit());
772 // It's not permitted to shadow a template parameter name.
773 if (Previous.isSingleResult() &&
774 Previous.getFoundDecl()->isTemplateParameter()) {
775 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
776 Previous.getFoundDecl());
780 bool ConsiderLinkage = DC->isFunctionOrMethod() &&
781 DS.getStorageClassSpec() == DeclSpec::SCS_extern;
782 FilterLookupForScope(Previous, DC, S, ConsiderLinkage,
783 /*AllowInlineNamespace*/false);
784 if (!Previous.empty()) {
785 auto *Old = Previous.getRepresentativeDecl();
786 Diag(B.NameLoc, diag::err_redefinition) << B.Name;
787 Diag(Old->getLocation(), diag::note_previous_definition);
790 auto *BD = BindingDecl::Create(Context, DC, B.NameLoc, B.Name);
791 PushOnScopeChains(BD, S, true);
792 Bindings.push_back(BD);
793 ParsingInitForAutoVars.insert(BD);
796 // There are no prior lookup results for the variable itself, because it
798 DeclarationNameInfo NameInfo((IdentifierInfo *)nullptr,
799 Decomp.getLSquareLoc());
800 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, ForRedeclaration);
802 // Build the variable that holds the non-decomposed object.
803 bool AddToScope = true;
805 ActOnVariableDeclarator(S, D, DC, TInfo, Previous,
806 MultiTemplateParamsArg(), AddToScope, Bindings);
807 CurContext->addHiddenDecl(New);
809 if (isInOpenMPDeclareTargetContext())
810 checkDeclIsAllowedInOpenMPTarget(nullptr, New);
815 static bool checkSimpleDecomposition(
816 Sema &S, ArrayRef<BindingDecl *> Bindings, ValueDecl *Src,
817 QualType DecompType, const llvm::APSInt &NumElems, QualType ElemType,
818 llvm::function_ref<ExprResult(SourceLocation, Expr *, unsigned)> GetInit) {
819 if ((int64_t)Bindings.size() != NumElems) {
820 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
821 << DecompType << (unsigned)Bindings.size() << NumElems.toString(10)
822 << (NumElems < Bindings.size());
827 for (auto *B : Bindings) {
828 SourceLocation Loc = B->getLocation();
829 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
832 E = GetInit(Loc, E.get(), I++);
835 B->setBinding(ElemType, E.get());
841 static bool checkArrayLikeDecomposition(Sema &S,
842 ArrayRef<BindingDecl *> Bindings,
843 ValueDecl *Src, QualType DecompType,
844 const llvm::APSInt &NumElems,
846 return checkSimpleDecomposition(
847 S, Bindings, Src, DecompType, NumElems, ElemType,
848 [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
849 ExprResult E = S.ActOnIntegerConstant(Loc, I);
852 return S.CreateBuiltinArraySubscriptExpr(Base, Loc, E.get(), Loc);
856 static bool checkArrayDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
857 ValueDecl *Src, QualType DecompType,
858 const ConstantArrayType *CAT) {
859 return checkArrayLikeDecomposition(S, Bindings, Src, DecompType,
860 llvm::APSInt(CAT->getSize()),
861 CAT->getElementType());
864 static bool checkVectorDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
865 ValueDecl *Src, QualType DecompType,
866 const VectorType *VT) {
867 return checkArrayLikeDecomposition(
868 S, Bindings, Src, DecompType, llvm::APSInt::get(VT->getNumElements()),
869 S.Context.getQualifiedType(VT->getElementType(),
870 DecompType.getQualifiers()));
873 static bool checkComplexDecomposition(Sema &S,
874 ArrayRef<BindingDecl *> Bindings,
875 ValueDecl *Src, QualType DecompType,
876 const ComplexType *CT) {
877 return checkSimpleDecomposition(
878 S, Bindings, Src, DecompType, llvm::APSInt::get(2),
879 S.Context.getQualifiedType(CT->getElementType(),
880 DecompType.getQualifiers()),
881 [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
882 return S.CreateBuiltinUnaryOp(Loc, I ? UO_Imag : UO_Real, Base);
886 static std::string printTemplateArgs(const PrintingPolicy &PrintingPolicy,
887 TemplateArgumentListInfo &Args) {
889 llvm::raw_svector_ostream OS(SS);
891 for (auto &Arg : Args.arguments()) {
894 Arg.getArgument().print(PrintingPolicy, OS);
900 static bool lookupStdTypeTraitMember(Sema &S, LookupResult &TraitMemberLookup,
901 SourceLocation Loc, StringRef Trait,
902 TemplateArgumentListInfo &Args,
904 auto DiagnoseMissing = [&] {
906 S.Diag(Loc, DiagID) << printTemplateArgs(S.Context.getPrintingPolicy(),
911 // FIXME: Factor out duplication with lookupPromiseType in SemaCoroutine.
912 NamespaceDecl *Std = S.getStdNamespace();
914 return DiagnoseMissing();
916 // Look up the trait itself, within namespace std. We can diagnose various
917 // problems with this lookup even if we've been asked to not diagnose a
918 // missing specialization, because this can only fail if the user has been
919 // declaring their own names in namespace std or we don't support the
920 // standard library implementation in use.
921 LookupResult Result(S, &S.PP.getIdentifierTable().get(Trait),
922 Loc, Sema::LookupOrdinaryName);
923 if (!S.LookupQualifiedName(Result, Std))
924 return DiagnoseMissing();
925 if (Result.isAmbiguous())
928 ClassTemplateDecl *TraitTD = Result.getAsSingle<ClassTemplateDecl>();
930 Result.suppressDiagnostics();
931 NamedDecl *Found = *Result.begin();
932 S.Diag(Loc, diag::err_std_type_trait_not_class_template) << Trait;
933 S.Diag(Found->getLocation(), diag::note_declared_at);
937 // Build the template-id.
938 QualType TraitTy = S.CheckTemplateIdType(TemplateName(TraitTD), Loc, Args);
939 if (TraitTy.isNull())
941 if (!S.isCompleteType(Loc, TraitTy)) {
943 S.RequireCompleteType(
944 Loc, TraitTy, DiagID,
945 printTemplateArgs(S.Context.getPrintingPolicy(), Args));
949 CXXRecordDecl *RD = TraitTy->getAsCXXRecordDecl();
950 assert(RD && "specialization of class template is not a class?");
952 // Look up the member of the trait type.
953 S.LookupQualifiedName(TraitMemberLookup, RD);
954 return TraitMemberLookup.isAmbiguous();
957 static TemplateArgumentLoc
958 getTrivialIntegralTemplateArgument(Sema &S, SourceLocation Loc, QualType T,
960 TemplateArgument Arg(S.Context, S.Context.MakeIntValue(I, T), T);
961 return S.getTrivialTemplateArgumentLoc(Arg, T, Loc);
964 static TemplateArgumentLoc
965 getTrivialTypeTemplateArgument(Sema &S, SourceLocation Loc, QualType T) {
966 return S.getTrivialTemplateArgumentLoc(TemplateArgument(T), QualType(), Loc);
969 namespace { enum class IsTupleLike { TupleLike, NotTupleLike, Error }; }
971 static IsTupleLike isTupleLike(Sema &S, SourceLocation Loc, QualType T,
972 llvm::APSInt &Size) {
973 EnterExpressionEvaluationContext ContextRAII(S, Sema::ConstantEvaluated);
975 DeclarationName Value = S.PP.getIdentifierInfo("value");
976 LookupResult R(S, Value, Loc, Sema::LookupOrdinaryName);
978 // Form template argument list for tuple_size<T>.
979 TemplateArgumentListInfo Args(Loc, Loc);
980 Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
982 // If there's no tuple_size specialization, it's not tuple-like.
983 if (lookupStdTypeTraitMember(S, R, Loc, "tuple_size", Args, /*DiagID*/0))
984 return IsTupleLike::NotTupleLike;
986 // If we get this far, we've committed to the tuple interpretation, but
987 // we can still fail if there actually isn't a usable ::value.
989 struct ICEDiagnoser : Sema::VerifyICEDiagnoser {
991 TemplateArgumentListInfo &Args;
992 ICEDiagnoser(LookupResult &R, TemplateArgumentListInfo &Args)
993 : R(R), Args(Args) {}
994 void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) {
995 S.Diag(Loc, diag::err_decomp_decl_std_tuple_size_not_constant)
996 << printTemplateArgs(S.Context.getPrintingPolicy(), Args);
998 } Diagnoser(R, Args);
1001 Diagnoser.diagnoseNotICE(S, Loc, SourceRange());
1002 return IsTupleLike::Error;
1006 S.BuildDeclarationNameExpr(CXXScopeSpec(), R, /*NeedsADL*/false);
1008 return IsTupleLike::Error;
1010 E = S.VerifyIntegerConstantExpression(E.get(), &Size, Diagnoser, false);
1012 return IsTupleLike::Error;
1014 return IsTupleLike::TupleLike;
1017 /// \return std::tuple_element<I, T>::type.
1018 static QualType getTupleLikeElementType(Sema &S, SourceLocation Loc,
1019 unsigned I, QualType T) {
1020 // Form template argument list for tuple_element<I, T>.
1021 TemplateArgumentListInfo Args(Loc, Loc);
1023 getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
1024 Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
1026 DeclarationName TypeDN = S.PP.getIdentifierInfo("type");
1027 LookupResult R(S, TypeDN, Loc, Sema::LookupOrdinaryName);
1028 if (lookupStdTypeTraitMember(
1029 S, R, Loc, "tuple_element", Args,
1030 diag::err_decomp_decl_std_tuple_element_not_specialized))
1033 auto *TD = R.getAsSingle<TypeDecl>();
1035 R.suppressDiagnostics();
1036 S.Diag(Loc, diag::err_decomp_decl_std_tuple_element_not_specialized)
1037 << printTemplateArgs(S.Context.getPrintingPolicy(), Args);
1039 S.Diag(R.getRepresentativeDecl()->getLocation(), diag::note_declared_at);
1043 return S.Context.getTypeDeclType(TD);
1047 struct BindingDiagnosticTrap {
1049 DiagnosticErrorTrap Trap;
1052 BindingDiagnosticTrap(Sema &S, BindingDecl *BD)
1053 : S(S), Trap(S.Diags), BD(BD) {}
1054 ~BindingDiagnosticTrap() {
1055 if (Trap.hasErrorOccurred())
1056 S.Diag(BD->getLocation(), diag::note_in_binding_decl_init) << BD;
1061 static bool checkTupleLikeDecomposition(Sema &S,
1062 ArrayRef<BindingDecl *> Bindings,
1063 VarDecl *Src, QualType DecompType,
1064 const llvm::APSInt &TupleSize) {
1065 if ((int64_t)Bindings.size() != TupleSize) {
1066 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
1067 << DecompType << (unsigned)Bindings.size() << TupleSize.toString(10)
1068 << (TupleSize < Bindings.size());
1072 if (Bindings.empty())
1075 DeclarationName GetDN = S.PP.getIdentifierInfo("get");
1078 // The unqualified-id get is looked up in the scope of E by class member
1080 LookupResult MemberGet(S, GetDN, Src->getLocation(), Sema::LookupMemberName);
1081 bool UseMemberGet = false;
1082 if (S.isCompleteType(Src->getLocation(), DecompType)) {
1083 if (auto *RD = DecompType->getAsCXXRecordDecl())
1084 S.LookupQualifiedName(MemberGet, RD);
1085 if (MemberGet.isAmbiguous())
1087 UseMemberGet = !MemberGet.empty();
1088 S.FilterAcceptableTemplateNames(MemberGet);
1092 for (auto *B : Bindings) {
1093 BindingDiagnosticTrap Trap(S, B);
1094 SourceLocation Loc = B->getLocation();
1096 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
1100 // e is an lvalue if the type of the entity is an lvalue reference and
1101 // an xvalue otherwise
1102 if (!Src->getType()->isLValueReferenceType())
1103 E = ImplicitCastExpr::Create(S.Context, E.get()->getType(), CK_NoOp,
1104 E.get(), nullptr, VK_XValue);
1106 TemplateArgumentListInfo Args(Loc, Loc);
1108 getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
1111 // if [lookup of member get] finds at least one declaration, the
1112 // initializer is e.get<i-1>().
1113 E = S.BuildMemberReferenceExpr(E.get(), DecompType, Loc, false,
1114 CXXScopeSpec(), SourceLocation(), nullptr,
1115 MemberGet, &Args, nullptr);
1119 E = S.ActOnCallExpr(nullptr, E.get(), Loc, None, Loc);
1121 // Otherwise, the initializer is get<i-1>(e), where get is looked up
1122 // in the associated namespaces.
1123 Expr *Get = UnresolvedLookupExpr::Create(
1124 S.Context, nullptr, NestedNameSpecifierLoc(), SourceLocation(),
1125 DeclarationNameInfo(GetDN, Loc), /*RequiresADL*/true, &Args,
1126 UnresolvedSetIterator(), UnresolvedSetIterator());
1128 Expr *Arg = E.get();
1129 E = S.ActOnCallExpr(nullptr, Get, Loc, Arg, Loc);
1133 Expr *Init = E.get();
1135 // Given the type T designated by std::tuple_element<i - 1, E>::type,
1136 QualType T = getTupleLikeElementType(S, Loc, I, DecompType);
1140 // each vi is a variable of type "reference to T" initialized with the
1141 // initializer, where the reference is an lvalue reference if the
1142 // initializer is an lvalue and an rvalue reference otherwise
1144 S.BuildReferenceType(T, E.get()->isLValue(), Loc, B->getDeclName());
1145 if (RefType.isNull())
1147 auto *RefVD = VarDecl::Create(
1148 S.Context, Src->getDeclContext(), Loc, Loc,
1149 B->getDeclName().getAsIdentifierInfo(), RefType,
1150 S.Context.getTrivialTypeSourceInfo(T, Loc), Src->getStorageClass());
1151 RefVD->setLexicalDeclContext(Src->getLexicalDeclContext());
1152 RefVD->setTSCSpec(Src->getTSCSpec());
1153 RefVD->setImplicit();
1154 if (Src->isInlineSpecified())
1155 RefVD->setInlineSpecified();
1156 RefVD->getLexicalDeclContext()->addHiddenDecl(RefVD);
1158 InitializedEntity Entity = InitializedEntity::InitializeBinding(RefVD);
1159 InitializationKind Kind = InitializationKind::CreateCopy(Loc, Loc);
1160 InitializationSequence Seq(S, Entity, Kind, Init);
1161 E = Seq.Perform(S, Entity, Kind, Init);
1164 E = S.ActOnFinishFullExpr(E.get(), Loc);
1167 RefVD->setInit(E.get());
1168 RefVD->checkInitIsICE();
1170 E = S.BuildDeclarationNameExpr(CXXScopeSpec(),
1171 DeclarationNameInfo(B->getDeclName(), Loc),
1176 B->setBinding(T, E.get());
1183 /// Find the base class to decompose in a built-in decomposition of a class type.
1184 /// This base class search is, unfortunately, not quite like any other that we
1185 /// perform anywhere else in C++.
1186 static const CXXRecordDecl *findDecomposableBaseClass(Sema &S,
1188 const CXXRecordDecl *RD,
1189 CXXCastPath &BasePath) {
1190 auto BaseHasFields = [](const CXXBaseSpecifier *Specifier,
1191 CXXBasePath &Path) {
1192 return Specifier->getType()->getAsCXXRecordDecl()->hasDirectFields();
1195 const CXXRecordDecl *ClassWithFields = nullptr;
1196 if (RD->hasDirectFields())
1198 // Otherwise, all of E's non-static data members shall be public direct
1200 ClassWithFields = RD;
1204 Paths.setOrigin(const_cast<CXXRecordDecl*>(RD));
1205 if (!RD->lookupInBases(BaseHasFields, Paths)) {
1206 // If no classes have fields, just decompose RD itself. (This will work
1207 // if and only if zero bindings were provided.)
1211 CXXBasePath *BestPath = nullptr;
1212 for (auto &P : Paths) {
1215 else if (!S.Context.hasSameType(P.back().Base->getType(),
1216 BestPath->back().Base->getType())) {
1218 S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
1219 << false << RD << BestPath->back().Base->getType()
1220 << P.back().Base->getType();
1222 } else if (P.Access < BestPath->Access) {
1227 // ... unambiguous ...
1228 QualType BaseType = BestPath->back().Base->getType();
1229 if (Paths.isAmbiguous(S.Context.getCanonicalType(BaseType))) {
1230 S.Diag(Loc, diag::err_decomp_decl_ambiguous_base)
1231 << RD << BaseType << S.getAmbiguousPathsDisplayString(Paths);
1235 // ... public base class of E.
1236 if (BestPath->Access != AS_public) {
1237 S.Diag(Loc, diag::err_decomp_decl_non_public_base)
1239 for (auto &BS : *BestPath) {
1240 if (BS.Base->getAccessSpecifier() != AS_public) {
1241 S.Diag(BS.Base->getLocStart(), diag::note_access_constrained_by_path)
1242 << (BS.Base->getAccessSpecifier() == AS_protected)
1243 << (BS.Base->getAccessSpecifierAsWritten() == AS_none);
1250 ClassWithFields = BaseType->getAsCXXRecordDecl();
1251 S.BuildBasePathArray(Paths, BasePath);
1254 // The above search did not check whether the selected class itself has base
1255 // classes with fields, so check that now.
1257 if (ClassWithFields->lookupInBases(BaseHasFields, Paths)) {
1258 S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
1259 << (ClassWithFields == RD) << RD << ClassWithFields
1260 << Paths.front().back().Base->getType();
1264 return ClassWithFields;
1267 static bool checkMemberDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
1268 ValueDecl *Src, QualType DecompType,
1269 const CXXRecordDecl *RD) {
1270 CXXCastPath BasePath;
1271 RD = findDecomposableBaseClass(S, Src->getLocation(), RD, BasePath);
1274 QualType BaseType = S.Context.getQualifiedType(S.Context.getRecordType(RD),
1275 DecompType.getQualifiers());
1277 auto DiagnoseBadNumberOfBindings = [&]() -> bool {
1278 unsigned NumFields =
1279 std::count_if(RD->field_begin(), RD->field_end(),
1280 [](FieldDecl *FD) { return !FD->isUnnamedBitfield(); });
1281 assert(Bindings.size() != NumFields);
1282 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
1283 << DecompType << (unsigned)Bindings.size() << NumFields
1284 << (NumFields < Bindings.size());
1288 // all of E's non-static data members shall be public [...] members,
1289 // E shall not have an anonymous union member, ...
1291 for (auto *FD : RD->fields()) {
1292 if (FD->isUnnamedBitfield())
1295 if (FD->isAnonymousStructOrUnion()) {
1296 S.Diag(Src->getLocation(), diag::err_decomp_decl_anon_union_member)
1297 << DecompType << FD->getType()->isUnionType();
1298 S.Diag(FD->getLocation(), diag::note_declared_at);
1302 // We have a real field to bind.
1303 if (I >= Bindings.size())
1304 return DiagnoseBadNumberOfBindings();
1305 auto *B = Bindings[I++];
1307 SourceLocation Loc = B->getLocation();
1308 if (FD->getAccess() != AS_public) {
1309 S.Diag(Loc, diag::err_decomp_decl_non_public_member) << FD << DecompType;
1311 // Determine whether the access specifier was explicit.
1312 bool Implicit = true;
1313 for (const auto *D : RD->decls()) {
1314 if (declaresSameEntity(D, FD))
1316 if (isa<AccessSpecDecl>(D)) {
1322 S.Diag(FD->getLocation(), diag::note_access_natural)
1323 << (FD->getAccess() == AS_protected) << Implicit;
1327 // Initialize the binding to Src.FD.
1328 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
1331 E = S.ImpCastExprToType(E.get(), BaseType, CK_UncheckedDerivedToBase,
1332 VK_LValue, &BasePath);
1335 E = S.BuildFieldReferenceExpr(E.get(), /*IsArrow*/ false, Loc,
1337 DeclAccessPair::make(FD, FD->getAccess()),
1338 DeclarationNameInfo(FD->getDeclName(), Loc));
1342 // If the type of the member is T, the referenced type is cv T, where cv is
1343 // the cv-qualification of the decomposition expression.
1345 // FIXME: We resolve a defect here: if the field is mutable, we do not add
1346 // 'const' to the type of the field.
1347 Qualifiers Q = DecompType.getQualifiers();
1348 if (FD->isMutable())
1350 B->setBinding(S.BuildQualifiedType(FD->getType(), Loc, Q), E.get());
1353 if (I != Bindings.size())
1354 return DiagnoseBadNumberOfBindings();
1359 void Sema::CheckCompleteDecompositionDeclaration(DecompositionDecl *DD) {
1360 QualType DecompType = DD->getType();
1362 // If the type of the decomposition is dependent, then so is the type of
1364 if (DecompType->isDependentType()) {
1365 for (auto *B : DD->bindings())
1366 B->setType(Context.DependentTy);
1370 DecompType = DecompType.getNonReferenceType();
1371 ArrayRef<BindingDecl*> Bindings = DD->bindings();
1373 // C++1z [dcl.decomp]/2:
1374 // If E is an array type [...]
1375 // As an extension, we also support decomposition of built-in complex and
1377 if (auto *CAT = Context.getAsConstantArrayType(DecompType)) {
1378 if (checkArrayDecomposition(*this, Bindings, DD, DecompType, CAT))
1379 DD->setInvalidDecl();
1382 if (auto *VT = DecompType->getAs<VectorType>()) {
1383 if (checkVectorDecomposition(*this, Bindings, DD, DecompType, VT))
1384 DD->setInvalidDecl();
1387 if (auto *CT = DecompType->getAs<ComplexType>()) {
1388 if (checkComplexDecomposition(*this, Bindings, DD, DecompType, CT))
1389 DD->setInvalidDecl();
1393 // C++1z [dcl.decomp]/3:
1394 // if the expression std::tuple_size<E>::value is a well-formed integral
1395 // constant expression, [...]
1396 llvm::APSInt TupleSize(32);
1397 switch (isTupleLike(*this, DD->getLocation(), DecompType, TupleSize)) {
1398 case IsTupleLike::Error:
1399 DD->setInvalidDecl();
1402 case IsTupleLike::TupleLike:
1403 if (checkTupleLikeDecomposition(*this, Bindings, DD, DecompType, TupleSize))
1404 DD->setInvalidDecl();
1407 case IsTupleLike::NotTupleLike:
1411 // C++1z [dcl.dcl]/8:
1412 // [E shall be of array or non-union class type]
1413 CXXRecordDecl *RD = DecompType->getAsCXXRecordDecl();
1414 if (!RD || RD->isUnion()) {
1415 Diag(DD->getLocation(), diag::err_decomp_decl_unbindable_type)
1416 << DD << !RD << DecompType;
1417 DD->setInvalidDecl();
1421 // C++1z [dcl.decomp]/4:
1422 // all of E's non-static data members shall be [...] direct members of
1423 // E or of the same unambiguous public base class of E, ...
1424 if (checkMemberDecomposition(*this, Bindings, DD, DecompType, RD))
1425 DD->setInvalidDecl();
1428 /// \brief Merge the exception specifications of two variable declarations.
1430 /// This is called when there's a redeclaration of a VarDecl. The function
1431 /// checks if the redeclaration might have an exception specification and
1432 /// validates compatibility and merges the specs if necessary.
1433 void Sema::MergeVarDeclExceptionSpecs(VarDecl *New, VarDecl *Old) {
1434 // Shortcut if exceptions are disabled.
1435 if (!getLangOpts().CXXExceptions)
1438 assert(Context.hasSameType(New->getType(), Old->getType()) &&
1439 "Should only be called if types are otherwise the same.");
1441 QualType NewType = New->getType();
1442 QualType OldType = Old->getType();
1444 // We're only interested in pointers and references to functions, as well
1445 // as pointers to member functions.
1446 if (const ReferenceType *R = NewType->getAs<ReferenceType>()) {
1447 NewType = R->getPointeeType();
1448 OldType = OldType->getAs<ReferenceType>()->getPointeeType();
1449 } else if (const PointerType *P = NewType->getAs<PointerType>()) {
1450 NewType = P->getPointeeType();
1451 OldType = OldType->getAs<PointerType>()->getPointeeType();
1452 } else if (const MemberPointerType *M = NewType->getAs<MemberPointerType>()) {
1453 NewType = M->getPointeeType();
1454 OldType = OldType->getAs<MemberPointerType>()->getPointeeType();
1457 if (!NewType->isFunctionProtoType())
1460 // There's lots of special cases for functions. For function pointers, system
1461 // libraries are hopefully not as broken so that we don't need these
1463 if (CheckEquivalentExceptionSpec(
1464 OldType->getAs<FunctionProtoType>(), Old->getLocation(),
1465 NewType->getAs<FunctionProtoType>(), New->getLocation())) {
1466 New->setInvalidDecl();
1470 /// CheckCXXDefaultArguments - Verify that the default arguments for a
1471 /// function declaration are well-formed according to C++
1472 /// [dcl.fct.default].
1473 void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) {
1474 unsigned NumParams = FD->getNumParams();
1477 // Find first parameter with a default argument
1478 for (p = 0; p < NumParams; ++p) {
1479 ParmVarDecl *Param = FD->getParamDecl(p);
1480 if (Param->hasDefaultArg())
1484 // C++11 [dcl.fct.default]p4:
1485 // In a given function declaration, each parameter subsequent to a parameter
1486 // with a default argument shall have a default argument supplied in this or
1487 // a previous declaration or shall be a function parameter pack. A default
1488 // argument shall not be redefined by a later declaration (not even to the
1490 unsigned LastMissingDefaultArg = 0;
1491 for (; p < NumParams; ++p) {
1492 ParmVarDecl *Param = FD->getParamDecl(p);
1493 if (!Param->hasDefaultArg() && !Param->isParameterPack()) {
1494 if (Param->isInvalidDecl())
1495 /* We already complained about this parameter. */;
1496 else if (Param->getIdentifier())
1497 Diag(Param->getLocation(),
1498 diag::err_param_default_argument_missing_name)
1499 << Param->getIdentifier();
1501 Diag(Param->getLocation(),
1502 diag::err_param_default_argument_missing);
1504 LastMissingDefaultArg = p;
1508 if (LastMissingDefaultArg > 0) {
1509 // Some default arguments were missing. Clear out all of the
1510 // default arguments up to (and including) the last missing
1511 // default argument, so that we leave the function parameters
1512 // in a semantically valid state.
1513 for (p = 0; p <= LastMissingDefaultArg; ++p) {
1514 ParmVarDecl *Param = FD->getParamDecl(p);
1515 if (Param->hasDefaultArg()) {
1516 Param->setDefaultArg(nullptr);
1522 // CheckConstexprParameterTypes - Check whether a function's parameter types
1523 // are all literal types. If so, return true. If not, produce a suitable
1524 // diagnostic and return false.
1525 static bool CheckConstexprParameterTypes(Sema &SemaRef,
1526 const FunctionDecl *FD) {
1527 unsigned ArgIndex = 0;
1528 const FunctionProtoType *FT = FD->getType()->getAs<FunctionProtoType>();
1529 for (FunctionProtoType::param_type_iterator i = FT->param_type_begin(),
1530 e = FT->param_type_end();
1531 i != e; ++i, ++ArgIndex) {
1532 const ParmVarDecl *PD = FD->getParamDecl(ArgIndex);
1533 SourceLocation ParamLoc = PD->getLocation();
1534 if (!(*i)->isDependentType() &&
1535 SemaRef.RequireLiteralType(ParamLoc, *i,
1536 diag::err_constexpr_non_literal_param,
1537 ArgIndex+1, PD->getSourceRange(),
1538 isa<CXXConstructorDecl>(FD)))
1544 /// \brief Get diagnostic %select index for tag kind for
1545 /// record diagnostic message.
1546 /// WARNING: Indexes apply to particular diagnostics only!
1548 /// \returns diagnostic %select index.
1549 static unsigned getRecordDiagFromTagKind(TagTypeKind Tag) {
1551 case TTK_Struct: return 0;
1552 case TTK_Interface: return 1;
1553 case TTK_Class: return 2;
1554 default: llvm_unreachable("Invalid tag kind for record diagnostic!");
1558 // CheckConstexprFunctionDecl - Check whether a function declaration satisfies
1559 // the requirements of a constexpr function definition or a constexpr
1560 // constructor definition. If so, return true. If not, produce appropriate
1561 // diagnostics and return false.
1563 // This implements C++11 [dcl.constexpr]p3,4, as amended by DR1360.
1564 bool Sema::CheckConstexprFunctionDecl(const FunctionDecl *NewFD) {
1565 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
1566 if (MD && MD->isInstance()) {
1567 // C++11 [dcl.constexpr]p4:
1568 // The definition of a constexpr constructor shall satisfy the following
1570 // - the class shall not have any virtual base classes;
1571 const CXXRecordDecl *RD = MD->getParent();
1572 if (RD->getNumVBases()) {
1573 Diag(NewFD->getLocation(), diag::err_constexpr_virtual_base)
1574 << isa<CXXConstructorDecl>(NewFD)
1575 << getRecordDiagFromTagKind(RD->getTagKind()) << RD->getNumVBases();
1576 for (const auto &I : RD->vbases())
1577 Diag(I.getLocStart(),
1578 diag::note_constexpr_virtual_base_here) << I.getSourceRange();
1583 if (!isa<CXXConstructorDecl>(NewFD)) {
1584 // C++11 [dcl.constexpr]p3:
1585 // The definition of a constexpr function shall satisfy the following
1587 // - it shall not be virtual;
1588 const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD);
1589 if (Method && Method->isVirtual()) {
1590 Method = Method->getCanonicalDecl();
1591 Diag(Method->getLocation(), diag::err_constexpr_virtual);
1593 // If it's not obvious why this function is virtual, find an overridden
1594 // function which uses the 'virtual' keyword.
1595 const CXXMethodDecl *WrittenVirtual = Method;
1596 while (!WrittenVirtual->isVirtualAsWritten())
1597 WrittenVirtual = *WrittenVirtual->begin_overridden_methods();
1598 if (WrittenVirtual != Method)
1599 Diag(WrittenVirtual->getLocation(),
1600 diag::note_overridden_virtual_function);
1604 // - its return type shall be a literal type;
1605 QualType RT = NewFD->getReturnType();
1606 if (!RT->isDependentType() &&
1607 RequireLiteralType(NewFD->getLocation(), RT,
1608 diag::err_constexpr_non_literal_return))
1612 // - each of its parameter types shall be a literal type;
1613 if (!CheckConstexprParameterTypes(*this, NewFD))
1619 /// Check the given declaration statement is legal within a constexpr function
1620 /// body. C++11 [dcl.constexpr]p3,p4, and C++1y [dcl.constexpr]p3.
1622 /// \return true if the body is OK (maybe only as an extension), false if we
1623 /// have diagnosed a problem.
1624 static bool CheckConstexprDeclStmt(Sema &SemaRef, const FunctionDecl *Dcl,
1625 DeclStmt *DS, SourceLocation &Cxx1yLoc) {
1626 // C++11 [dcl.constexpr]p3 and p4:
1627 // The definition of a constexpr function(p3) or constructor(p4) [...] shall
1629 for (const auto *DclIt : DS->decls()) {
1630 switch (DclIt->getKind()) {
1631 case Decl::StaticAssert:
1633 case Decl::UsingShadow:
1634 case Decl::UsingDirective:
1635 case Decl::UnresolvedUsingTypename:
1636 case Decl::UnresolvedUsingValue:
1637 // - static_assert-declarations
1638 // - using-declarations,
1639 // - using-directives,
1643 case Decl::TypeAlias: {
1644 // - typedef declarations and alias-declarations that do not define
1645 // classes or enumerations,
1646 const auto *TN = cast<TypedefNameDecl>(DclIt);
1647 if (TN->getUnderlyingType()->isVariablyModifiedType()) {
1648 // Don't allow variably-modified types in constexpr functions.
1649 TypeLoc TL = TN->getTypeSourceInfo()->getTypeLoc();
1650 SemaRef.Diag(TL.getBeginLoc(), diag::err_constexpr_vla)
1651 << TL.getSourceRange() << TL.getType()
1652 << isa<CXXConstructorDecl>(Dcl);
1659 case Decl::CXXRecord:
1660 // C++1y allows types to be defined, not just declared.
1661 if (cast<TagDecl>(DclIt)->isThisDeclarationADefinition())
1662 SemaRef.Diag(DS->getLocStart(),
1663 SemaRef.getLangOpts().CPlusPlus14
1664 ? diag::warn_cxx11_compat_constexpr_type_definition
1665 : diag::ext_constexpr_type_definition)
1666 << isa<CXXConstructorDecl>(Dcl);
1669 case Decl::EnumConstant:
1670 case Decl::IndirectField:
1672 // These can only appear with other declarations which are banned in
1673 // C++11 and permitted in C++1y, so ignore them.
1677 case Decl::Decomposition: {
1678 // C++1y [dcl.constexpr]p3 allows anything except:
1679 // a definition of a variable of non-literal type or of static or
1680 // thread storage duration or for which no initialization is performed.
1681 const auto *VD = cast<VarDecl>(DclIt);
1682 if (VD->isThisDeclarationADefinition()) {
1683 if (VD->isStaticLocal()) {
1684 SemaRef.Diag(VD->getLocation(),
1685 diag::err_constexpr_local_var_static)
1686 << isa<CXXConstructorDecl>(Dcl)
1687 << (VD->getTLSKind() == VarDecl::TLS_Dynamic);
1690 if (!VD->getType()->isDependentType() &&
1691 SemaRef.RequireLiteralType(
1692 VD->getLocation(), VD->getType(),
1693 diag::err_constexpr_local_var_non_literal_type,
1694 isa<CXXConstructorDecl>(Dcl)))
1696 if (!VD->getType()->isDependentType() &&
1697 !VD->hasInit() && !VD->isCXXForRangeDecl()) {
1698 SemaRef.Diag(VD->getLocation(),
1699 diag::err_constexpr_local_var_no_init)
1700 << isa<CXXConstructorDecl>(Dcl);
1704 SemaRef.Diag(VD->getLocation(),
1705 SemaRef.getLangOpts().CPlusPlus14
1706 ? diag::warn_cxx11_compat_constexpr_local_var
1707 : diag::ext_constexpr_local_var)
1708 << isa<CXXConstructorDecl>(Dcl);
1712 case Decl::NamespaceAlias:
1713 case Decl::Function:
1714 // These are disallowed in C++11 and permitted in C++1y. Allow them
1715 // everywhere as an extension.
1716 if (!Cxx1yLoc.isValid())
1717 Cxx1yLoc = DS->getLocStart();
1721 SemaRef.Diag(DS->getLocStart(), diag::err_constexpr_body_invalid_stmt)
1722 << isa<CXXConstructorDecl>(Dcl);
1730 /// Check that the given field is initialized within a constexpr constructor.
1732 /// \param Dcl The constexpr constructor being checked.
1733 /// \param Field The field being checked. This may be a member of an anonymous
1734 /// struct or union nested within the class being checked.
1735 /// \param Inits All declarations, including anonymous struct/union members and
1736 /// indirect members, for which any initialization was provided.
1737 /// \param Diagnosed Set to true if an error is produced.
1738 static void CheckConstexprCtorInitializer(Sema &SemaRef,
1739 const FunctionDecl *Dcl,
1741 llvm::SmallSet<Decl*, 16> &Inits,
1743 if (Field->isInvalidDecl())
1746 if (Field->isUnnamedBitfield())
1749 // Anonymous unions with no variant members and empty anonymous structs do not
1750 // need to be explicitly initialized. FIXME: Anonymous structs that contain no
1751 // indirect fields don't need initializing.
1752 if (Field->isAnonymousStructOrUnion() &&
1753 (Field->getType()->isUnionType()
1754 ? !Field->getType()->getAsCXXRecordDecl()->hasVariantMembers()
1755 : Field->getType()->getAsCXXRecordDecl()->isEmpty()))
1758 if (!Inits.count(Field)) {
1760 SemaRef.Diag(Dcl->getLocation(), diag::err_constexpr_ctor_missing_init);
1763 SemaRef.Diag(Field->getLocation(), diag::note_constexpr_ctor_missing_init);
1764 } else if (Field->isAnonymousStructOrUnion()) {
1765 const RecordDecl *RD = Field->getType()->castAs<RecordType>()->getDecl();
1766 for (auto *I : RD->fields())
1767 // If an anonymous union contains an anonymous struct of which any member
1768 // is initialized, all members must be initialized.
1769 if (!RD->isUnion() || Inits.count(I))
1770 CheckConstexprCtorInitializer(SemaRef, Dcl, I, Inits, Diagnosed);
1774 /// Check the provided statement is allowed in a constexpr function
1777 CheckConstexprFunctionStmt(Sema &SemaRef, const FunctionDecl *Dcl, Stmt *S,
1778 SmallVectorImpl<SourceLocation> &ReturnStmts,
1779 SourceLocation &Cxx1yLoc) {
1780 // - its function-body shall be [...] a compound-statement that contains only
1781 switch (S->getStmtClass()) {
1782 case Stmt::NullStmtClass:
1783 // - null statements,
1786 case Stmt::DeclStmtClass:
1787 // - static_assert-declarations
1788 // - using-declarations,
1789 // - using-directives,
1790 // - typedef declarations and alias-declarations that do not define
1791 // classes or enumerations,
1792 if (!CheckConstexprDeclStmt(SemaRef, Dcl, cast<DeclStmt>(S), Cxx1yLoc))
1796 case Stmt::ReturnStmtClass:
1797 // - and exactly one return statement;
1798 if (isa<CXXConstructorDecl>(Dcl)) {
1799 // C++1y allows return statements in constexpr constructors.
1800 if (!Cxx1yLoc.isValid())
1801 Cxx1yLoc = S->getLocStart();
1805 ReturnStmts.push_back(S->getLocStart());
1808 case Stmt::CompoundStmtClass: {
1809 // C++1y allows compound-statements.
1810 if (!Cxx1yLoc.isValid())
1811 Cxx1yLoc = S->getLocStart();
1813 CompoundStmt *CompStmt = cast<CompoundStmt>(S);
1814 for (auto *BodyIt : CompStmt->body()) {
1815 if (!CheckConstexprFunctionStmt(SemaRef, Dcl, BodyIt, ReturnStmts,
1822 case Stmt::AttributedStmtClass:
1823 if (!Cxx1yLoc.isValid())
1824 Cxx1yLoc = S->getLocStart();
1827 case Stmt::IfStmtClass: {
1828 // C++1y allows if-statements.
1829 if (!Cxx1yLoc.isValid())
1830 Cxx1yLoc = S->getLocStart();
1832 IfStmt *If = cast<IfStmt>(S);
1833 if (!CheckConstexprFunctionStmt(SemaRef, Dcl, If->getThen(), ReturnStmts,
1836 if (If->getElse() &&
1837 !CheckConstexprFunctionStmt(SemaRef, Dcl, If->getElse(), ReturnStmts,
1843 case Stmt::WhileStmtClass:
1844 case Stmt::DoStmtClass:
1845 case Stmt::ForStmtClass:
1846 case Stmt::CXXForRangeStmtClass:
1847 case Stmt::ContinueStmtClass:
1848 // C++1y allows all of these. We don't allow them as extensions in C++11,
1849 // because they don't make sense without variable mutation.
1850 if (!SemaRef.getLangOpts().CPlusPlus14)
1852 if (!Cxx1yLoc.isValid())
1853 Cxx1yLoc = S->getLocStart();
1854 for (Stmt *SubStmt : S->children())
1856 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
1861 case Stmt::SwitchStmtClass:
1862 case Stmt::CaseStmtClass:
1863 case Stmt::DefaultStmtClass:
1864 case Stmt::BreakStmtClass:
1865 // C++1y allows switch-statements, and since they don't need variable
1866 // mutation, we can reasonably allow them in C++11 as an extension.
1867 if (!Cxx1yLoc.isValid())
1868 Cxx1yLoc = S->getLocStart();
1869 for (Stmt *SubStmt : S->children())
1871 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
1880 // C++1y allows expression-statements.
1881 if (!Cxx1yLoc.isValid())
1882 Cxx1yLoc = S->getLocStart();
1886 SemaRef.Diag(S->getLocStart(), diag::err_constexpr_body_invalid_stmt)
1887 << isa<CXXConstructorDecl>(Dcl);
1891 /// Check the body for the given constexpr function declaration only contains
1892 /// the permitted types of statement. C++11 [dcl.constexpr]p3,p4.
1894 /// \return true if the body is OK, false if we have diagnosed a problem.
1895 bool Sema::CheckConstexprFunctionBody(const FunctionDecl *Dcl, Stmt *Body) {
1896 if (isa<CXXTryStmt>(Body)) {
1897 // C++11 [dcl.constexpr]p3:
1898 // The definition of a constexpr function shall satisfy the following
1899 // constraints: [...]
1900 // - its function-body shall be = delete, = default, or a
1901 // compound-statement
1903 // C++11 [dcl.constexpr]p4:
1904 // In the definition of a constexpr constructor, [...]
1905 // - its function-body shall not be a function-try-block;
1906 Diag(Body->getLocStart(), diag::err_constexpr_function_try_block)
1907 << isa<CXXConstructorDecl>(Dcl);
1911 SmallVector<SourceLocation, 4> ReturnStmts;
1913 // - its function-body shall be [...] a compound-statement that contains only
1914 // [... list of cases ...]
1915 CompoundStmt *CompBody = cast<CompoundStmt>(Body);
1916 SourceLocation Cxx1yLoc;
1917 for (auto *BodyIt : CompBody->body()) {
1918 if (!CheckConstexprFunctionStmt(*this, Dcl, BodyIt, ReturnStmts, Cxx1yLoc))
1922 if (Cxx1yLoc.isValid())
1924 getLangOpts().CPlusPlus14
1925 ? diag::warn_cxx11_compat_constexpr_body_invalid_stmt
1926 : diag::ext_constexpr_body_invalid_stmt)
1927 << isa<CXXConstructorDecl>(Dcl);
1929 if (const CXXConstructorDecl *Constructor
1930 = dyn_cast<CXXConstructorDecl>(Dcl)) {
1931 const CXXRecordDecl *RD = Constructor->getParent();
1933 // - every non-variant non-static data member and base class sub-object
1934 // shall be initialized;
1936 // - if the class is a union having variant members, exactly one of them
1937 // shall be initialized;
1938 if (RD->isUnion()) {
1939 if (Constructor->getNumCtorInitializers() == 0 &&
1940 RD->hasVariantMembers()) {
1941 Diag(Dcl->getLocation(), diag::err_constexpr_union_ctor_no_init);
1944 } else if (!Constructor->isDependentContext() &&
1945 !Constructor->isDelegatingConstructor()) {
1946 assert(RD->getNumVBases() == 0 && "constexpr ctor with virtual bases");
1948 // Skip detailed checking if we have enough initializers, and we would
1949 // allow at most one initializer per member.
1950 bool AnyAnonStructUnionMembers = false;
1951 unsigned Fields = 0;
1952 for (CXXRecordDecl::field_iterator I = RD->field_begin(),
1953 E = RD->field_end(); I != E; ++I, ++Fields) {
1954 if (I->isAnonymousStructOrUnion()) {
1955 AnyAnonStructUnionMembers = true;
1960 // - if the class is a union-like class, but is not a union, for each of
1961 // its anonymous union members having variant members, exactly one of
1962 // them shall be initialized;
1963 if (AnyAnonStructUnionMembers ||
1964 Constructor->getNumCtorInitializers() != RD->getNumBases() + Fields) {
1965 // Check initialization of non-static data members. Base classes are
1966 // always initialized so do not need to be checked. Dependent bases
1967 // might not have initializers in the member initializer list.
1968 llvm::SmallSet<Decl*, 16> Inits;
1969 for (const auto *I: Constructor->inits()) {
1970 if (FieldDecl *FD = I->getMember())
1972 else if (IndirectFieldDecl *ID = I->getIndirectMember())
1973 Inits.insert(ID->chain_begin(), ID->chain_end());
1976 bool Diagnosed = false;
1977 for (auto *I : RD->fields())
1978 CheckConstexprCtorInitializer(*this, Dcl, I, Inits, Diagnosed);
1984 if (ReturnStmts.empty()) {
1985 // C++1y doesn't require constexpr functions to contain a 'return'
1986 // statement. We still do, unless the return type might be void, because
1987 // otherwise if there's no return statement, the function cannot
1988 // be used in a core constant expression.
1989 bool OK = getLangOpts().CPlusPlus14 &&
1990 (Dcl->getReturnType()->isVoidType() ||
1991 Dcl->getReturnType()->isDependentType());
1992 Diag(Dcl->getLocation(),
1993 OK ? diag::warn_cxx11_compat_constexpr_body_no_return
1994 : diag::err_constexpr_body_no_return);
1997 } else if (ReturnStmts.size() > 1) {
1998 Diag(ReturnStmts.back(),
1999 getLangOpts().CPlusPlus14
2000 ? diag::warn_cxx11_compat_constexpr_body_multiple_return
2001 : diag::ext_constexpr_body_multiple_return);
2002 for (unsigned I = 0; I < ReturnStmts.size() - 1; ++I)
2003 Diag(ReturnStmts[I], diag::note_constexpr_body_previous_return);
2007 // C++11 [dcl.constexpr]p5:
2008 // if no function argument values exist such that the function invocation
2009 // substitution would produce a constant expression, the program is
2010 // ill-formed; no diagnostic required.
2011 // C++11 [dcl.constexpr]p3:
2012 // - every constructor call and implicit conversion used in initializing the
2013 // return value shall be one of those allowed in a constant expression.
2014 // C++11 [dcl.constexpr]p4:
2015 // - every constructor involved in initializing non-static data members and
2016 // base class sub-objects shall be a constexpr constructor.
2017 SmallVector<PartialDiagnosticAt, 8> Diags;
2018 if (!Expr::isPotentialConstantExpr(Dcl, Diags)) {
2019 Diag(Dcl->getLocation(), diag::ext_constexpr_function_never_constant_expr)
2020 << isa<CXXConstructorDecl>(Dcl);
2021 for (size_t I = 0, N = Diags.size(); I != N; ++I)
2022 Diag(Diags[I].first, Diags[I].second);
2023 // Don't return false here: we allow this for compatibility in
2030 /// isCurrentClassName - Determine whether the identifier II is the
2031 /// name of the class type currently being defined. In the case of
2032 /// nested classes, this will only return true if II is the name of
2033 /// the innermost class.
2034 bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *,
2035 const CXXScopeSpec *SS) {
2036 assert(getLangOpts().CPlusPlus && "No class names in C!");
2038 CXXRecordDecl *CurDecl;
2039 if (SS && SS->isSet() && !SS->isInvalid()) {
2040 DeclContext *DC = computeDeclContext(*SS, true);
2041 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
2043 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
2045 if (CurDecl && CurDecl->getIdentifier())
2046 return &II == CurDecl->getIdentifier();
2050 /// \brief Determine whether the identifier II is a typo for the name of
2051 /// the class type currently being defined. If so, update it to the identifier
2052 /// that should have been used.
2053 bool Sema::isCurrentClassNameTypo(IdentifierInfo *&II, const CXXScopeSpec *SS) {
2054 assert(getLangOpts().CPlusPlus && "No class names in C!");
2056 if (!getLangOpts().SpellChecking)
2059 CXXRecordDecl *CurDecl;
2060 if (SS && SS->isSet() && !SS->isInvalid()) {
2061 DeclContext *DC = computeDeclContext(*SS, true);
2062 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
2064 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
2066 if (CurDecl && CurDecl->getIdentifier() && II != CurDecl->getIdentifier() &&
2067 3 * II->getName().edit_distance(CurDecl->getIdentifier()->getName())
2068 < II->getLength()) {
2069 II = CurDecl->getIdentifier();
2076 /// \brief Determine whether the given class is a base class of the given
2077 /// class, including looking at dependent bases.
2078 static bool findCircularInheritance(const CXXRecordDecl *Class,
2079 const CXXRecordDecl *Current) {
2080 SmallVector<const CXXRecordDecl*, 8> Queue;
2082 Class = Class->getCanonicalDecl();
2084 for (const auto &I : Current->bases()) {
2085 CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
2089 Base = Base->getDefinition();
2093 if (Base->getCanonicalDecl() == Class)
2096 Queue.push_back(Base);
2102 Current = Queue.pop_back_val();
2108 /// \brief Check the validity of a C++ base class specifier.
2110 /// \returns a new CXXBaseSpecifier if well-formed, emits diagnostics
2111 /// and returns NULL otherwise.
2113 Sema::CheckBaseSpecifier(CXXRecordDecl *Class,
2114 SourceRange SpecifierRange,
2115 bool Virtual, AccessSpecifier Access,
2116 TypeSourceInfo *TInfo,
2117 SourceLocation EllipsisLoc) {
2118 QualType BaseType = TInfo->getType();
2120 // C++ [class.union]p1:
2121 // A union shall not have base classes.
2122 if (Class->isUnion()) {
2123 Diag(Class->getLocation(), diag::err_base_clause_on_union)
2128 if (EllipsisLoc.isValid() &&
2129 !TInfo->getType()->containsUnexpandedParameterPack()) {
2130 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
2131 << TInfo->getTypeLoc().getSourceRange();
2132 EllipsisLoc = SourceLocation();
2135 SourceLocation BaseLoc = TInfo->getTypeLoc().getBeginLoc();
2137 if (BaseType->isDependentType()) {
2138 // Make sure that we don't have circular inheritance among our dependent
2139 // bases. For non-dependent bases, the check for completeness below handles
2141 if (CXXRecordDecl *BaseDecl = BaseType->getAsCXXRecordDecl()) {
2142 if (BaseDecl->getCanonicalDecl() == Class->getCanonicalDecl() ||
2143 ((BaseDecl = BaseDecl->getDefinition()) &&
2144 findCircularInheritance(Class, BaseDecl))) {
2145 Diag(BaseLoc, diag::err_circular_inheritance)
2146 << BaseType << Context.getTypeDeclType(Class);
2148 if (BaseDecl->getCanonicalDecl() != Class->getCanonicalDecl())
2149 Diag(BaseDecl->getLocation(), diag::note_previous_decl)
2156 return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
2157 Class->getTagKind() == TTK_Class,
2158 Access, TInfo, EllipsisLoc);
2161 // Base specifiers must be record types.
2162 if (!BaseType->isRecordType()) {
2163 Diag(BaseLoc, diag::err_base_must_be_class) << SpecifierRange;
2167 // C++ [class.union]p1:
2168 // A union shall not be used as a base class.
2169 if (BaseType->isUnionType()) {
2170 Diag(BaseLoc, diag::err_union_as_base_class) << SpecifierRange;
2174 // For the MS ABI, propagate DLL attributes to base class templates.
2175 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
2176 if (Attr *ClassAttr = getDLLAttr(Class)) {
2177 if (auto *BaseTemplate = dyn_cast_or_null<ClassTemplateSpecializationDecl>(
2178 BaseType->getAsCXXRecordDecl())) {
2179 propagateDLLAttrToBaseClassTemplate(Class, ClassAttr, BaseTemplate,
2185 // C++ [class.derived]p2:
2186 // The class-name in a base-specifier shall not be an incompletely
2188 if (RequireCompleteType(BaseLoc, BaseType,
2189 diag::err_incomplete_base_class, SpecifierRange)) {
2190 Class->setInvalidDecl();
2194 // If the base class is polymorphic or isn't empty, the new one is/isn't, too.
2195 RecordDecl *BaseDecl = BaseType->getAs<RecordType>()->getDecl();
2196 assert(BaseDecl && "Record type has no declaration");
2197 BaseDecl = BaseDecl->getDefinition();
2198 assert(BaseDecl && "Base type is not incomplete, but has no definition");
2199 CXXRecordDecl *CXXBaseDecl = cast<CXXRecordDecl>(BaseDecl);
2200 assert(CXXBaseDecl && "Base type is not a C++ type");
2202 // A class which contains a flexible array member is not suitable for use as a
2204 // - If the layout determines that a base comes before another base,
2205 // the flexible array member would index into the subsequent base.
2206 // - If the layout determines that base comes before the derived class,
2207 // the flexible array member would index into the derived class.
2208 if (CXXBaseDecl->hasFlexibleArrayMember()) {
2209 Diag(BaseLoc, diag::err_base_class_has_flexible_array_member)
2210 << CXXBaseDecl->getDeclName();
2215 // If a class is marked final and it appears as a base-type-specifier in
2216 // base-clause, the program is ill-formed.
2217 if (FinalAttr *FA = CXXBaseDecl->getAttr<FinalAttr>()) {
2218 Diag(BaseLoc, diag::err_class_marked_final_used_as_base)
2219 << CXXBaseDecl->getDeclName()
2220 << FA->isSpelledAsSealed();
2221 Diag(CXXBaseDecl->getLocation(), diag::note_entity_declared_at)
2222 << CXXBaseDecl->getDeclName() << FA->getRange();
2226 if (BaseDecl->isInvalidDecl())
2227 Class->setInvalidDecl();
2229 // Create the base specifier.
2230 return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
2231 Class->getTagKind() == TTK_Class,
2232 Access, TInfo, EllipsisLoc);
2235 /// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is
2236 /// one entry in the base class list of a class specifier, for
2238 /// class foo : public bar, virtual private baz {
2239 /// 'public bar' and 'virtual private baz' are each base-specifiers.
2241 Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
2242 ParsedAttributes &Attributes,
2243 bool Virtual, AccessSpecifier Access,
2244 ParsedType basetype, SourceLocation BaseLoc,
2245 SourceLocation EllipsisLoc) {
2249 AdjustDeclIfTemplate(classdecl);
2250 CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(classdecl);
2254 // We haven't yet attached the base specifiers.
2255 Class->setIsParsingBaseSpecifiers();
2257 // We do not support any C++11 attributes on base-specifiers yet.
2258 // Diagnose any attributes we see.
2259 if (!Attributes.empty()) {
2260 for (AttributeList *Attr = Attributes.getList(); Attr;
2261 Attr = Attr->getNext()) {
2262 if (Attr->isInvalid() ||
2263 Attr->getKind() == AttributeList::IgnoredAttribute)
2265 Diag(Attr->getLoc(),
2266 Attr->getKind() == AttributeList::UnknownAttribute
2267 ? diag::warn_unknown_attribute_ignored
2268 : diag::err_base_specifier_attribute)
2273 TypeSourceInfo *TInfo = nullptr;
2274 GetTypeFromParser(basetype, &TInfo);
2276 if (EllipsisLoc.isInvalid() &&
2277 DiagnoseUnexpandedParameterPack(SpecifierRange.getBegin(), TInfo,
2281 if (CXXBaseSpecifier *BaseSpec = CheckBaseSpecifier(Class, SpecifierRange,
2282 Virtual, Access, TInfo,
2286 Class->setInvalidDecl();
2291 /// Use small set to collect indirect bases. As this is only used
2292 /// locally, there's no need to abstract the small size parameter.
2293 typedef llvm::SmallPtrSet<QualType, 4> IndirectBaseSet;
2295 /// \brief Recursively add the bases of Type. Don't add Type itself.
2297 NoteIndirectBases(ASTContext &Context, IndirectBaseSet &Set,
2298 const QualType &Type)
2300 // Even though the incoming type is a base, it might not be
2301 // a class -- it could be a template parm, for instance.
2302 if (auto Rec = Type->getAs<RecordType>()) {
2303 auto Decl = Rec->getAsCXXRecordDecl();
2305 // Iterate over its bases.
2306 for (const auto &BaseSpec : Decl->bases()) {
2307 QualType Base = Context.getCanonicalType(BaseSpec.getType())
2308 .getUnqualifiedType();
2309 if (Set.insert(Base).second)
2310 // If we've not already seen it, recurse.
2311 NoteIndirectBases(Context, Set, Base);
2316 /// \brief Performs the actual work of attaching the given base class
2317 /// specifiers to a C++ class.
2318 bool Sema::AttachBaseSpecifiers(CXXRecordDecl *Class,
2319 MutableArrayRef<CXXBaseSpecifier *> Bases) {
2323 // Used to keep track of which base types we have already seen, so
2324 // that we can properly diagnose redundant direct base types. Note
2325 // that the key is always the unqualified canonical type of the base
2327 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes;
2329 // Used to track indirect bases so we can see if a direct base is
2331 IndirectBaseSet IndirectBaseTypes;
2333 // Copy non-redundant base specifiers into permanent storage.
2334 unsigned NumGoodBases = 0;
2335 bool Invalid = false;
2336 for (unsigned idx = 0; idx < Bases.size(); ++idx) {
2337 QualType NewBaseType
2338 = Context.getCanonicalType(Bases[idx]->getType());
2339 NewBaseType = NewBaseType.getLocalUnqualifiedType();
2341 CXXBaseSpecifier *&KnownBase = KnownBaseTypes[NewBaseType];
2343 // C++ [class.mi]p3:
2344 // A class shall not be specified as a direct base class of a
2345 // derived class more than once.
2346 Diag(Bases[idx]->getLocStart(),
2347 diag::err_duplicate_base_class)
2348 << KnownBase->getType()
2349 << Bases[idx]->getSourceRange();
2351 // Delete the duplicate base class specifier; we're going to
2352 // overwrite its pointer later.
2353 Context.Deallocate(Bases[idx]);
2357 // Okay, add this new base class.
2358 KnownBase = Bases[idx];
2359 Bases[NumGoodBases++] = Bases[idx];
2361 // Note this base's direct & indirect bases, if there could be ambiguity.
2362 if (Bases.size() > 1)
2363 NoteIndirectBases(Context, IndirectBaseTypes, NewBaseType);
2365 if (const RecordType *Record = NewBaseType->getAs<RecordType>()) {
2366 const CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
2367 if (Class->isInterface() &&
2368 (!RD->isInterface() ||
2369 KnownBase->getAccessSpecifier() != AS_public)) {
2370 // The Microsoft extension __interface does not permit bases that
2371 // are not themselves public interfaces.
2372 Diag(KnownBase->getLocStart(), diag::err_invalid_base_in_interface)
2373 << getRecordDiagFromTagKind(RD->getTagKind()) << RD->getName()
2374 << RD->getSourceRange();
2377 if (RD->hasAttr<WeakAttr>())
2378 Class->addAttr(WeakAttr::CreateImplicit(Context));
2383 // Attach the remaining base class specifiers to the derived class.
2384 Class->setBases(Bases.data(), NumGoodBases);
2386 for (unsigned idx = 0; idx < NumGoodBases; ++idx) {
2387 // Check whether this direct base is inaccessible due to ambiguity.
2388 QualType BaseType = Bases[idx]->getType();
2389 CanQualType CanonicalBase = Context.getCanonicalType(BaseType)
2390 .getUnqualifiedType();
2392 if (IndirectBaseTypes.count(CanonicalBase)) {
2393 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2394 /*DetectVirtual=*/true);
2396 = Class->isDerivedFrom(CanonicalBase->getAsCXXRecordDecl(), Paths);
2400 if (Paths.isAmbiguous(CanonicalBase))
2401 Diag(Bases[idx]->getLocStart (), diag::warn_inaccessible_base_class)
2402 << BaseType << getAmbiguousPathsDisplayString(Paths)
2403 << Bases[idx]->getSourceRange();
2405 assert(Bases[idx]->isVirtual());
2408 // Delete the base class specifier, since its data has been copied
2409 // into the CXXRecordDecl.
2410 Context.Deallocate(Bases[idx]);
2416 /// ActOnBaseSpecifiers - Attach the given base specifiers to the
2417 /// class, after checking whether there are any duplicate base
2419 void Sema::ActOnBaseSpecifiers(Decl *ClassDecl,
2420 MutableArrayRef<CXXBaseSpecifier *> Bases) {
2421 if (!ClassDecl || Bases.empty())
2424 AdjustDeclIfTemplate(ClassDecl);
2425 AttachBaseSpecifiers(cast<CXXRecordDecl>(ClassDecl), Bases);
2428 /// \brief Determine whether the type \p Derived is a C++ class that is
2429 /// derived from the type \p Base.
2430 bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base) {
2431 if (!getLangOpts().CPlusPlus)
2434 CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
2438 CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
2442 // If either the base or the derived type is invalid, don't try to
2443 // check whether one is derived from the other.
2444 if (BaseRD->isInvalidDecl() || DerivedRD->isInvalidDecl())
2447 // FIXME: In a modules build, do we need the entire path to be visible for us
2448 // to be able to use the inheritance relationship?
2449 if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
2452 return DerivedRD->isDerivedFrom(BaseRD);
2455 /// \brief Determine whether the type \p Derived is a C++ class that is
2456 /// derived from the type \p Base.
2457 bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base,
2458 CXXBasePaths &Paths) {
2459 if (!getLangOpts().CPlusPlus)
2462 CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
2466 CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
2470 if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
2473 return DerivedRD->isDerivedFrom(BaseRD, Paths);
2476 void Sema::BuildBasePathArray(const CXXBasePaths &Paths,
2477 CXXCastPath &BasePathArray) {
2478 assert(BasePathArray.empty() && "Base path array must be empty!");
2479 assert(Paths.isRecordingPaths() && "Must record paths!");
2481 const CXXBasePath &Path = Paths.front();
2483 // We first go backward and check if we have a virtual base.
2484 // FIXME: It would be better if CXXBasePath had the base specifier for
2485 // the nearest virtual base.
2487 for (unsigned I = Path.size(); I != 0; --I) {
2488 if (Path[I - 1].Base->isVirtual()) {
2494 // Now add all bases.
2495 for (unsigned I = Start, E = Path.size(); I != E; ++I)
2496 BasePathArray.push_back(const_cast<CXXBaseSpecifier*>(Path[I].Base));
2499 /// CheckDerivedToBaseConversion - Check whether the Derived-to-Base
2500 /// conversion (where Derived and Base are class types) is
2501 /// well-formed, meaning that the conversion is unambiguous (and
2502 /// that all of the base classes are accessible). Returns true
2503 /// and emits a diagnostic if the code is ill-formed, returns false
2504 /// otherwise. Loc is the location where this routine should point to
2505 /// if there is an error, and Range is the source range to highlight
2506 /// if there is an error.
2508 /// If either InaccessibleBaseID or AmbigiousBaseConvID are 0, then the
2509 /// diagnostic for the respective type of error will be suppressed, but the
2510 /// check for ill-formed code will still be performed.
2512 Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
2513 unsigned InaccessibleBaseID,
2514 unsigned AmbigiousBaseConvID,
2515 SourceLocation Loc, SourceRange Range,
2516 DeclarationName Name,
2517 CXXCastPath *BasePath,
2518 bool IgnoreAccess) {
2519 // First, determine whether the path from Derived to Base is
2520 // ambiguous. This is slightly more expensive than checking whether
2521 // the Derived to Base conversion exists, because here we need to
2522 // explore multiple paths to determine if there is an ambiguity.
2523 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2524 /*DetectVirtual=*/false);
2525 bool DerivationOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
2526 assert(DerivationOkay &&
2527 "Can only be used with a derived-to-base conversion");
2528 (void)DerivationOkay;
2530 if (!Paths.isAmbiguous(Context.getCanonicalType(Base).getUnqualifiedType())) {
2531 if (!IgnoreAccess) {
2532 // Check that the base class can be accessed.
2533 switch (CheckBaseClassAccess(Loc, Base, Derived, Paths.front(),
2534 InaccessibleBaseID)) {
2535 case AR_inaccessible:
2544 // Build a base path if necessary.
2546 BuildBasePathArray(Paths, *BasePath);
2550 if (AmbigiousBaseConvID) {
2551 // We know that the derived-to-base conversion is ambiguous, and
2552 // we're going to produce a diagnostic. Perform the derived-to-base
2553 // search just one more time to compute all of the possible paths so
2554 // that we can print them out. This is more expensive than any of
2555 // the previous derived-to-base checks we've done, but at this point
2556 // performance isn't as much of an issue.
2558 Paths.setRecordingPaths(true);
2559 bool StillOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
2560 assert(StillOkay && "Can only be used with a derived-to-base conversion");
2563 // Build up a textual representation of the ambiguous paths, e.g.,
2564 // D -> B -> A, that will be used to illustrate the ambiguous
2565 // conversions in the diagnostic. We only print one of the paths
2566 // to each base class subobject.
2567 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths);
2569 Diag(Loc, AmbigiousBaseConvID)
2570 << Derived << Base << PathDisplayStr << Range << Name;
2576 Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
2577 SourceLocation Loc, SourceRange Range,
2578 CXXCastPath *BasePath,
2579 bool IgnoreAccess) {
2580 return CheckDerivedToBaseConversion(
2581 Derived, Base, diag::err_upcast_to_inaccessible_base,
2582 diag::err_ambiguous_derived_to_base_conv, Loc, Range, DeclarationName(),
2583 BasePath, IgnoreAccess);
2587 /// @brief Builds a string representing ambiguous paths from a
2588 /// specific derived class to different subobjects of the same base
2591 /// This function builds a string that can be used in error messages
2592 /// to show the different paths that one can take through the
2593 /// inheritance hierarchy to go from the derived class to different
2594 /// subobjects of a base class. The result looks something like this:
2596 /// struct D -> struct B -> struct A
2597 /// struct D -> struct C -> struct A
2599 std::string Sema::getAmbiguousPathsDisplayString(CXXBasePaths &Paths) {
2600 std::string PathDisplayStr;
2601 std::set<unsigned> DisplayedPaths;
2602 for (CXXBasePaths::paths_iterator Path = Paths.begin();
2603 Path != Paths.end(); ++Path) {
2604 if (DisplayedPaths.insert(Path->back().SubobjectNumber).second) {
2605 // We haven't displayed a path to this particular base
2606 // class subobject yet.
2607 PathDisplayStr += "\n ";
2608 PathDisplayStr += Context.getTypeDeclType(Paths.getOrigin()).getAsString();
2609 for (CXXBasePath::const_iterator Element = Path->begin();
2610 Element != Path->end(); ++Element)
2611 PathDisplayStr += " -> " + Element->Base->getType().getAsString();
2615 return PathDisplayStr;
2618 //===----------------------------------------------------------------------===//
2619 // C++ class member Handling
2620 //===----------------------------------------------------------------------===//
2622 /// ActOnAccessSpecifier - Parsed an access specifier followed by a colon.
2623 bool Sema::ActOnAccessSpecifier(AccessSpecifier Access,
2624 SourceLocation ASLoc,
2625 SourceLocation ColonLoc,
2626 AttributeList *Attrs) {
2627 assert(Access != AS_none && "Invalid kind for syntactic access specifier!");
2628 AccessSpecDecl *ASDecl = AccessSpecDecl::Create(Context, Access, CurContext,
2630 CurContext->addHiddenDecl(ASDecl);
2631 return ProcessAccessDeclAttributeList(ASDecl, Attrs);
2634 /// CheckOverrideControl - Check C++11 override control semantics.
2635 void Sema::CheckOverrideControl(NamedDecl *D) {
2636 if (D->isInvalidDecl())
2639 // We only care about "override" and "final" declarations.
2640 if (!D->hasAttr<OverrideAttr>() && !D->hasAttr<FinalAttr>())
2643 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
2645 // We can't check dependent instance methods.
2646 if (MD && MD->isInstance() &&
2647 (MD->getParent()->hasAnyDependentBases() ||
2648 MD->getType()->isDependentType()))
2651 if (MD && !MD->isVirtual()) {
2652 // If we have a non-virtual method, check if if hides a virtual method.
2653 // (In that case, it's most likely the method has the wrong type.)
2654 SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
2655 FindHiddenVirtualMethods(MD, OverloadedMethods);
2657 if (!OverloadedMethods.empty()) {
2658 if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
2659 Diag(OA->getLocation(),
2660 diag::override_keyword_hides_virtual_member_function)
2661 << "override" << (OverloadedMethods.size() > 1);
2662 } else if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
2663 Diag(FA->getLocation(),
2664 diag::override_keyword_hides_virtual_member_function)
2665 << (FA->isSpelledAsSealed() ? "sealed" : "final")
2666 << (OverloadedMethods.size() > 1);
2668 NoteHiddenVirtualMethods(MD, OverloadedMethods);
2669 MD->setInvalidDecl();
2672 // Fall through into the general case diagnostic.
2673 // FIXME: We might want to attempt typo correction here.
2676 if (!MD || !MD->isVirtual()) {
2677 if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
2678 Diag(OA->getLocation(),
2679 diag::override_keyword_only_allowed_on_virtual_member_functions)
2680 << "override" << FixItHint::CreateRemoval(OA->getLocation());
2681 D->dropAttr<OverrideAttr>();
2683 if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
2684 Diag(FA->getLocation(),
2685 diag::override_keyword_only_allowed_on_virtual_member_functions)
2686 << (FA->isSpelledAsSealed() ? "sealed" : "final")
2687 << FixItHint::CreateRemoval(FA->getLocation());
2688 D->dropAttr<FinalAttr>();
2693 // C++11 [class.virtual]p5:
2694 // If a function is marked with the virt-specifier override and
2695 // does not override a member function of a base class, the program is
2697 bool HasOverriddenMethods =
2698 MD->begin_overridden_methods() != MD->end_overridden_methods();
2699 if (MD->hasAttr<OverrideAttr>() && !HasOverriddenMethods)
2700 Diag(MD->getLocation(), diag::err_function_marked_override_not_overriding)
2701 << MD->getDeclName();
2704 void Sema::DiagnoseAbsenceOfOverrideControl(NamedDecl *D) {
2705 if (D->isInvalidDecl() || D->hasAttr<OverrideAttr>())
2707 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
2708 if (!MD || MD->isImplicit() || MD->hasAttr<FinalAttr>() ||
2709 isa<CXXDestructorDecl>(MD))
2712 SourceLocation Loc = MD->getLocation();
2713 SourceLocation SpellingLoc = Loc;
2714 if (getSourceManager().isMacroArgExpansion(Loc))
2715 SpellingLoc = getSourceManager().getImmediateExpansionRange(Loc).first;
2716 SpellingLoc = getSourceManager().getSpellingLoc(SpellingLoc);
2717 if (SpellingLoc.isValid() && getSourceManager().isInSystemHeader(SpellingLoc))
2720 if (MD->size_overridden_methods() > 0) {
2721 Diag(MD->getLocation(), diag::warn_function_marked_not_override_overriding)
2722 << MD->getDeclName();
2723 const CXXMethodDecl *OMD = *MD->begin_overridden_methods();
2724 Diag(OMD->getLocation(), diag::note_overridden_virtual_function);
2728 /// CheckIfOverriddenFunctionIsMarkedFinal - Checks whether a virtual member
2729 /// function overrides a virtual member function marked 'final', according to
2730 /// C++11 [class.virtual]p4.
2731 bool Sema::CheckIfOverriddenFunctionIsMarkedFinal(const CXXMethodDecl *New,
2732 const CXXMethodDecl *Old) {
2733 FinalAttr *FA = Old->getAttr<FinalAttr>();
2737 Diag(New->getLocation(), diag::err_final_function_overridden)
2738 << New->getDeclName()
2739 << FA->isSpelledAsSealed();
2740 Diag(Old->getLocation(), diag::note_overridden_virtual_function);
2744 static bool InitializationHasSideEffects(const FieldDecl &FD) {
2745 const Type *T = FD.getType()->getBaseElementTypeUnsafe();
2746 // FIXME: Destruction of ObjC lifetime types has side-effects.
2747 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
2748 return !RD->isCompleteDefinition() ||
2749 !RD->hasTrivialDefaultConstructor() ||
2750 !RD->hasTrivialDestructor();
2754 static AttributeList *getMSPropertyAttr(AttributeList *list) {
2755 for (AttributeList *it = list; it != nullptr; it = it->getNext())
2756 if (it->isDeclspecPropertyAttribute())
2761 /// ActOnCXXMemberDeclarator - This is invoked when a C++ class member
2762 /// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the
2763 /// bitfield width if there is one, 'InitExpr' specifies the initializer if
2764 /// one has been parsed, and 'InitStyle' is set if an in-class initializer is
2765 /// present (but parsing it has been deferred).
2767 Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D,
2768 MultiTemplateParamsArg TemplateParameterLists,
2769 Expr *BW, const VirtSpecifiers &VS,
2770 InClassInitStyle InitStyle) {
2771 const DeclSpec &DS = D.getDeclSpec();
2772 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
2773 DeclarationName Name = NameInfo.getName();
2774 SourceLocation Loc = NameInfo.getLoc();
2776 // For anonymous bitfields, the location should point to the type.
2777 if (Loc.isInvalid())
2778 Loc = D.getLocStart();
2780 Expr *BitWidth = static_cast<Expr*>(BW);
2782 assert(isa<CXXRecordDecl>(CurContext));
2783 assert(!DS.isFriendSpecified());
2785 bool isFunc = D.isDeclarationOfFunction();
2787 if (cast<CXXRecordDecl>(CurContext)->isInterface()) {
2788 // The Microsoft extension __interface only permits public member functions
2789 // and prohibits constructors, destructors, operators, non-public member
2790 // functions, static methods and data members.
2791 unsigned InvalidDecl;
2792 bool ShowDeclName = true;
2794 InvalidDecl = (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) ? 0 : 1;
2795 else if (AS != AS_public)
2797 else if (DS.getStorageClassSpec() == DeclSpec::SCS_static)
2799 else switch (Name.getNameKind()) {
2800 case DeclarationName::CXXConstructorName:
2802 ShowDeclName = false;
2805 case DeclarationName::CXXDestructorName:
2807 ShowDeclName = false;
2810 case DeclarationName::CXXOperatorName:
2811 case DeclarationName::CXXConversionFunctionName:
2822 Diag(Loc, diag::err_invalid_member_in_interface)
2823 << (InvalidDecl-1) << Name;
2825 Diag(Loc, diag::err_invalid_member_in_interface)
2826 << (InvalidDecl-1) << "";
2831 // C++ 9.2p6: A member shall not be declared to have automatic storage
2832 // duration (auto, register) or with the extern storage-class-specifier.
2833 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class
2834 // data members and cannot be applied to names declared const or static,
2835 // and cannot be applied to reference members.
2836 switch (DS.getStorageClassSpec()) {
2837 case DeclSpec::SCS_unspecified:
2838 case DeclSpec::SCS_typedef:
2839 case DeclSpec::SCS_static:
2841 case DeclSpec::SCS_mutable:
2843 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_function);
2845 // FIXME: It would be nicer if the keyword was ignored only for this
2846 // declarator. Otherwise we could get follow-up errors.
2847 D.getMutableDeclSpec().ClearStorageClassSpecs();
2851 Diag(DS.getStorageClassSpecLoc(),
2852 diag::err_storageclass_invalid_for_member);
2853 D.getMutableDeclSpec().ClearStorageClassSpecs();
2857 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified ||
2858 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) &&
2861 if (DS.isConstexprSpecified() && isInstField) {
2862 SemaDiagnosticBuilder B =
2863 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr_member);
2864 SourceLocation ConstexprLoc = DS.getConstexprSpecLoc();
2865 if (InitStyle == ICIS_NoInit) {
2867 if (D.getDeclSpec().getTypeQualifiers() & DeclSpec::TQ_const)
2868 B << FixItHint::CreateRemoval(ConstexprLoc);
2870 B << FixItHint::CreateReplacement(ConstexprLoc, "const");
2871 D.getMutableDeclSpec().ClearConstexprSpec();
2872 const char *PrevSpec;
2874 bool Failed = D.getMutableDeclSpec().SetTypeQual(
2875 DeclSpec::TQ_const, ConstexprLoc, PrevSpec, DiagID, getLangOpts());
2877 assert(!Failed && "Making a constexpr member const shouldn't fail");
2881 const char *PrevSpec;
2883 if (D.getMutableDeclSpec().SetStorageClassSpec(
2884 *this, DeclSpec::SCS_static, ConstexprLoc, PrevSpec, DiagID,
2885 Context.getPrintingPolicy())) {
2886 assert(DS.getStorageClassSpec() == DeclSpec::SCS_mutable &&
2887 "This is the only DeclSpec that should fail to be applied");
2890 B << 0 << FixItHint::CreateInsertion(ConstexprLoc, "static ");
2891 isInstField = false;
2898 CXXScopeSpec &SS = D.getCXXScopeSpec();
2900 // Data members must have identifiers for names.
2901 if (!Name.isIdentifier()) {
2902 Diag(Loc, diag::err_bad_variable_name)
2907 IdentifierInfo *II = Name.getAsIdentifierInfo();
2909 // Member field could not be with "template" keyword.
2910 // So TemplateParameterLists should be empty in this case.
2911 if (TemplateParameterLists.size()) {
2912 TemplateParameterList* TemplateParams = TemplateParameterLists[0];
2913 if (TemplateParams->size()) {
2914 // There is no such thing as a member field template.
2915 Diag(D.getIdentifierLoc(), diag::err_template_member)
2917 << SourceRange(TemplateParams->getTemplateLoc(),
2918 TemplateParams->getRAngleLoc());
2920 // There is an extraneous 'template<>' for this member.
2921 Diag(TemplateParams->getTemplateLoc(),
2922 diag::err_template_member_noparams)
2924 << SourceRange(TemplateParams->getTemplateLoc(),
2925 TemplateParams->getRAngleLoc());
2930 if (SS.isSet() && !SS.isInvalid()) {
2931 // The user provided a superfluous scope specifier inside a class
2937 if (DeclContext *DC = computeDeclContext(SS, false))
2938 diagnoseQualifiedDeclaration(SS, DC, Name, D.getIdentifierLoc());
2940 Diag(D.getIdentifierLoc(), diag::err_member_qualification)
2941 << Name << SS.getRange();
2946 AttributeList *MSPropertyAttr =
2947 getMSPropertyAttr(D.getDeclSpec().getAttributes().getList());
2948 if (MSPropertyAttr) {
2949 Member = HandleMSProperty(S, cast<CXXRecordDecl>(CurContext), Loc, D,
2950 BitWidth, InitStyle, AS, MSPropertyAttr);
2953 isInstField = false;
2955 Member = HandleField(S, cast<CXXRecordDecl>(CurContext), Loc, D,
2956 BitWidth, InitStyle, AS);
2961 Member = HandleDeclarator(S, D, TemplateParameterLists);
2965 // Non-instance-fields can't have a bitfield.
2967 if (Member->isInvalidDecl()) {
2968 // don't emit another diagnostic.
2969 } else if (isa<VarDecl>(Member) || isa<VarTemplateDecl>(Member)) {
2970 // C++ 9.6p3: A bit-field shall not be a static member.
2971 // "static member 'A' cannot be a bit-field"
2972 Diag(Loc, diag::err_static_not_bitfield)
2973 << Name << BitWidth->getSourceRange();
2974 } else if (isa<TypedefDecl>(Member)) {
2975 // "typedef member 'x' cannot be a bit-field"
2976 Diag(Loc, diag::err_typedef_not_bitfield)
2977 << Name << BitWidth->getSourceRange();
2979 // A function typedef ("typedef int f(); f a;").
2980 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
2981 Diag(Loc, diag::err_not_integral_type_bitfield)
2982 << Name << cast<ValueDecl>(Member)->getType()
2983 << BitWidth->getSourceRange();
2987 Member->setInvalidDecl();
2990 Member->setAccess(AS);
2992 // If we have declared a member function template or static data member
2993 // template, set the access of the templated declaration as well.
2994 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Member))
2995 FunTmpl->getTemplatedDecl()->setAccess(AS);
2996 else if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(Member))
2997 VarTmpl->getTemplatedDecl()->setAccess(AS);
3000 if (VS.isOverrideSpecified())
3001 Member->addAttr(new (Context) OverrideAttr(VS.getOverrideLoc(), Context, 0));
3002 if (VS.isFinalSpecified())
3003 Member->addAttr(new (Context) FinalAttr(VS.getFinalLoc(), Context,
3004 VS.isFinalSpelledSealed()));
3006 if (VS.getLastLocation().isValid()) {
3007 // Update the end location of a method that has a virt-specifiers.
3008 if (CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Member))
3009 MD->setRangeEnd(VS.getLastLocation());
3012 CheckOverrideControl(Member);
3014 assert((Name || isInstField) && "No identifier for non-field ?");
3017 FieldDecl *FD = cast<FieldDecl>(Member);
3018 FieldCollector->Add(FD);
3020 if (!Diags.isIgnored(diag::warn_unused_private_field, FD->getLocation())) {
3021 // Remember all explicit private FieldDecls that have a name, no side
3022 // effects and are not part of a dependent type declaration.
3023 if (!FD->isImplicit() && FD->getDeclName() &&
3024 FD->getAccess() == AS_private &&
3025 !FD->hasAttr<UnusedAttr>() &&
3026 !FD->getParent()->isDependentContext() &&
3027 !InitializationHasSideEffects(*FD))
3028 UnusedPrivateFields.insert(FD);
3036 class UninitializedFieldVisitor
3037 : public EvaluatedExprVisitor<UninitializedFieldVisitor> {
3039 // List of Decls to generate a warning on. Also remove Decls that become
3041 llvm::SmallPtrSetImpl<ValueDecl*> &Decls;
3042 // List of base classes of the record. Classes are removed after their
3044 llvm::SmallPtrSetImpl<QualType> &BaseClasses;
3045 // Vector of decls to be removed from the Decl set prior to visiting the
3046 // nodes. These Decls may have been initialized in the prior initializer.
3047 llvm::SmallVector<ValueDecl*, 4> DeclsToRemove;
3048 // If non-null, add a note to the warning pointing back to the constructor.
3049 const CXXConstructorDecl *Constructor;
3050 // Variables to hold state when processing an initializer list. When
3051 // InitList is true, special case initialization of FieldDecls matching
3052 // InitListFieldDecl.
3054 FieldDecl *InitListFieldDecl;
3055 llvm::SmallVector<unsigned, 4> InitFieldIndex;
3058 typedef EvaluatedExprVisitor<UninitializedFieldVisitor> Inherited;
3059 UninitializedFieldVisitor(Sema &S,
3060 llvm::SmallPtrSetImpl<ValueDecl*> &Decls,
3061 llvm::SmallPtrSetImpl<QualType> &BaseClasses)
3062 : Inherited(S.Context), S(S), Decls(Decls), BaseClasses(BaseClasses),
3063 Constructor(nullptr), InitList(false), InitListFieldDecl(nullptr) {}
3065 // Returns true if the use of ME is not an uninitialized use.
3066 bool IsInitListMemberExprInitialized(MemberExpr *ME,
3067 bool CheckReferenceOnly) {
3068 llvm::SmallVector<FieldDecl*, 4> Fields;
3069 bool ReferenceField = false;
3071 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
3074 Fields.push_back(FD);
3075 if (FD->getType()->isReferenceType())
3076 ReferenceField = true;
3077 ME = dyn_cast<MemberExpr>(ME->getBase()->IgnoreParenImpCasts());
3080 // Binding a reference to an unintialized field is not an
3081 // uninitialized use.
3082 if (CheckReferenceOnly && !ReferenceField)
3085 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
3086 // Discard the first field since it is the field decl that is being
3088 for (auto I = Fields.rbegin() + 1, E = Fields.rend(); I != E; ++I) {
3089 UsedFieldIndex.push_back((*I)->getFieldIndex());
3092 for (auto UsedIter = UsedFieldIndex.begin(),
3093 UsedEnd = UsedFieldIndex.end(),
3094 OrigIter = InitFieldIndex.begin(),
3095 OrigEnd = InitFieldIndex.end();
3096 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
3097 if (*UsedIter < *OrigIter)
3099 if (*UsedIter > *OrigIter)
3106 void HandleMemberExpr(MemberExpr *ME, bool CheckReferenceOnly,
3108 if (isa<EnumConstantDecl>(ME->getMemberDecl()))
3111 // FieldME is the inner-most MemberExpr that is not an anonymous struct
3113 MemberExpr *FieldME = ME;
3115 bool AllPODFields = FieldME->getType().isPODType(S.Context);
3118 while (MemberExpr *SubME =
3119 dyn_cast<MemberExpr>(Base->IgnoreParenImpCasts())) {
3121 if (isa<VarDecl>(SubME->getMemberDecl()))
3124 if (FieldDecl *FD = dyn_cast<FieldDecl>(SubME->getMemberDecl()))
3125 if (!FD->isAnonymousStructOrUnion())
3128 if (!FieldME->getType().isPODType(S.Context))
3129 AllPODFields = false;
3131 Base = SubME->getBase();
3134 if (!isa<CXXThisExpr>(Base->IgnoreParenImpCasts()))
3137 if (AddressOf && AllPODFields)
3140 ValueDecl* FoundVD = FieldME->getMemberDecl();
3142 if (ImplicitCastExpr *BaseCast = dyn_cast<ImplicitCastExpr>(Base)) {
3143 while (isa<ImplicitCastExpr>(BaseCast->getSubExpr())) {
3144 BaseCast = cast<ImplicitCastExpr>(BaseCast->getSubExpr());
3147 if (BaseCast->getCastKind() == CK_UncheckedDerivedToBase) {
3148 QualType T = BaseCast->getType();
3149 if (T->isPointerType() &&
3150 BaseClasses.count(T->getPointeeType())) {
3151 S.Diag(FieldME->getExprLoc(), diag::warn_base_class_is_uninit)
3152 << T->getPointeeType() << FoundVD;
3157 if (!Decls.count(FoundVD))
3160 const bool IsReference = FoundVD->getType()->isReferenceType();
3162 if (InitList && !AddressOf && FoundVD == InitListFieldDecl) {
3163 // Special checking for initializer lists.
3164 if (IsInitListMemberExprInitialized(ME, CheckReferenceOnly)) {
3168 // Prevent double warnings on use of unbounded references.
3169 if (CheckReferenceOnly && !IsReference)
3173 unsigned diag = IsReference
3174 ? diag::warn_reference_field_is_uninit
3175 : diag::warn_field_is_uninit;
3176 S.Diag(FieldME->getExprLoc(), diag) << FoundVD;
3178 S.Diag(Constructor->getLocation(),
3179 diag::note_uninit_in_this_constructor)
3180 << (Constructor->isDefaultConstructor() && Constructor->isImplicit());
3184 void HandleValue(Expr *E, bool AddressOf) {
3185 E = E->IgnoreParens();
3187 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
3188 HandleMemberExpr(ME, false /*CheckReferenceOnly*/,
3189 AddressOf /*AddressOf*/);
3193 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
3194 Visit(CO->getCond());
3195 HandleValue(CO->getTrueExpr(), AddressOf);
3196 HandleValue(CO->getFalseExpr(), AddressOf);
3200 if (BinaryConditionalOperator *BCO =
3201 dyn_cast<BinaryConditionalOperator>(E)) {
3202 Visit(BCO->getCond());
3203 HandleValue(BCO->getFalseExpr(), AddressOf);
3207 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
3208 HandleValue(OVE->getSourceExpr(), AddressOf);
3212 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
3213 switch (BO->getOpcode()) {
3218 HandleValue(BO->getLHS(), AddressOf);
3219 Visit(BO->getRHS());
3222 Visit(BO->getLHS());
3223 HandleValue(BO->getRHS(), AddressOf);
3231 void CheckInitListExpr(InitListExpr *ILE) {
3232 InitFieldIndex.push_back(0);
3233 for (auto Child : ILE->children()) {
3234 if (InitListExpr *SubList = dyn_cast<InitListExpr>(Child)) {
3235 CheckInitListExpr(SubList);
3239 ++InitFieldIndex.back();
3241 InitFieldIndex.pop_back();
3244 void CheckInitializer(Expr *E, const CXXConstructorDecl *FieldConstructor,
3245 FieldDecl *Field, const Type *BaseClass) {
3246 // Remove Decls that may have been initialized in the previous
3248 for (ValueDecl* VD : DeclsToRemove)
3250 DeclsToRemove.clear();
3252 Constructor = FieldConstructor;
3253 InitListExpr *ILE = dyn_cast<InitListExpr>(E);
3257 InitListFieldDecl = Field;
3258 InitFieldIndex.clear();
3259 CheckInitListExpr(ILE);
3268 BaseClasses.erase(BaseClass->getCanonicalTypeInternal());
3271 void VisitMemberExpr(MemberExpr *ME) {
3272 // All uses of unbounded reference fields will warn.
3273 HandleMemberExpr(ME, true /*CheckReferenceOnly*/, false /*AddressOf*/);
3276 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
3277 if (E->getCastKind() == CK_LValueToRValue) {
3278 HandleValue(E->getSubExpr(), false /*AddressOf*/);
3282 Inherited::VisitImplicitCastExpr(E);
3285 void VisitCXXConstructExpr(CXXConstructExpr *E) {
3286 if (E->getConstructor()->isCopyConstructor()) {
3287 Expr *ArgExpr = E->getArg(0);
3288 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
3289 if (ILE->getNumInits() == 1)
3290 ArgExpr = ILE->getInit(0);
3291 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
3292 if (ICE->getCastKind() == CK_NoOp)
3293 ArgExpr = ICE->getSubExpr();
3294 HandleValue(ArgExpr, false /*AddressOf*/);
3297 Inherited::VisitCXXConstructExpr(E);
3300 void VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
3301 Expr *Callee = E->getCallee();
3302 if (isa<MemberExpr>(Callee)) {
3303 HandleValue(Callee, false /*AddressOf*/);
3304 for (auto Arg : E->arguments())
3309 Inherited::VisitCXXMemberCallExpr(E);
3312 void VisitCallExpr(CallExpr *E) {
3313 // Treat std::move as a use.
3314 if (E->getNumArgs() == 1) {
3315 if (FunctionDecl *FD = E->getDirectCallee()) {
3316 if (FD->isInStdNamespace() && FD->getIdentifier() &&
3317 FD->getIdentifier()->isStr("move")) {
3318 HandleValue(E->getArg(0), false /*AddressOf*/);
3324 Inherited::VisitCallExpr(E);
3327 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
3328 Expr *Callee = E->getCallee();
3330 if (isa<UnresolvedLookupExpr>(Callee))
3331 return Inherited::VisitCXXOperatorCallExpr(E);
3334 for (auto Arg : E->arguments())
3335 HandleValue(Arg->IgnoreParenImpCasts(), false /*AddressOf*/);
3338 void VisitBinaryOperator(BinaryOperator *E) {
3339 // If a field assignment is detected, remove the field from the
3340 // uninitiailized field set.
3341 if (E->getOpcode() == BO_Assign)
3342 if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getLHS()))
3343 if (FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
3344 if (!FD->getType()->isReferenceType())
3345 DeclsToRemove.push_back(FD);
3347 if (E->isCompoundAssignmentOp()) {
3348 HandleValue(E->getLHS(), false /*AddressOf*/);
3353 Inherited::VisitBinaryOperator(E);
3356 void VisitUnaryOperator(UnaryOperator *E) {
3357 if (E->isIncrementDecrementOp()) {
3358 HandleValue(E->getSubExpr(), false /*AddressOf*/);
3361 if (E->getOpcode() == UO_AddrOf) {
3362 if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getSubExpr())) {
3363 HandleValue(ME->getBase(), true /*AddressOf*/);
3368 Inherited::VisitUnaryOperator(E);
3372 // Diagnose value-uses of fields to initialize themselves, e.g.
3374 // where foo is not also a parameter to the constructor.
3375 // Also diagnose across field uninitialized use such as
3377 // TODO: implement -Wuninitialized and fold this into that framework.
3378 static void DiagnoseUninitializedFields(
3379 Sema &SemaRef, const CXXConstructorDecl *Constructor) {
3381 if (SemaRef.getDiagnostics().isIgnored(diag::warn_field_is_uninit,
3382 Constructor->getLocation())) {
3386 if (Constructor->isInvalidDecl())
3389 const CXXRecordDecl *RD = Constructor->getParent();
3391 if (RD->getDescribedClassTemplate())
3394 // Holds fields that are uninitialized.
3395 llvm::SmallPtrSet<ValueDecl*, 4> UninitializedFields;
3397 // At the beginning, all fields are uninitialized.
3398 for (auto *I : RD->decls()) {
3399 if (auto *FD = dyn_cast<FieldDecl>(I)) {
3400 UninitializedFields.insert(FD);
3401 } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(I)) {
3402 UninitializedFields.insert(IFD->getAnonField());
3406 llvm::SmallPtrSet<QualType, 4> UninitializedBaseClasses;
3407 for (auto I : RD->bases())
3408 UninitializedBaseClasses.insert(I.getType().getCanonicalType());
3410 if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
3413 UninitializedFieldVisitor UninitializedChecker(SemaRef,
3414 UninitializedFields,
3415 UninitializedBaseClasses);
3417 for (const auto *FieldInit : Constructor->inits()) {
3418 if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
3421 Expr *InitExpr = FieldInit->getInit();
3425 if (CXXDefaultInitExpr *Default =
3426 dyn_cast<CXXDefaultInitExpr>(InitExpr)) {
3427 InitExpr = Default->getExpr();
3430 // In class initializers will point to the constructor.
3431 UninitializedChecker.CheckInitializer(InitExpr, Constructor,
3432 FieldInit->getAnyMember(),
3433 FieldInit->getBaseClass());
3435 UninitializedChecker.CheckInitializer(InitExpr, nullptr,
3436 FieldInit->getAnyMember(),
3437 FieldInit->getBaseClass());
3443 /// \brief Enter a new C++ default initializer scope. After calling this, the
3444 /// caller must call \ref ActOnFinishCXXInClassMemberInitializer, even if
3445 /// parsing or instantiating the initializer failed.
3446 void Sema::ActOnStartCXXInClassMemberInitializer() {
3447 // Create a synthetic function scope to represent the call to the constructor
3448 // that notionally surrounds a use of this initializer.
3449 PushFunctionScope();
3452 /// \brief This is invoked after parsing an in-class initializer for a
3453 /// non-static C++ class member, and after instantiating an in-class initializer
3454 /// in a class template. Such actions are deferred until the class is complete.
3455 void Sema::ActOnFinishCXXInClassMemberInitializer(Decl *D,
3456 SourceLocation InitLoc,
3458 // Pop the notional constructor scope we created earlier.
3459 PopFunctionScopeInfo(nullptr, D);
3461 FieldDecl *FD = dyn_cast<FieldDecl>(D);
3462 assert((isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) &&
3463 "must set init style when field is created");
3466 D->setInvalidDecl();
3468 FD->removeInClassInitializer();
3472 if (DiagnoseUnexpandedParameterPack(InitExpr, UPPC_Initializer)) {
3473 FD->setInvalidDecl();
3474 FD->removeInClassInitializer();
3478 ExprResult Init = InitExpr;
3479 if (!FD->getType()->isDependentType() && !InitExpr->isTypeDependent()) {
3480 InitializedEntity Entity = InitializedEntity::InitializeMember(FD);
3481 InitializationKind Kind = FD->getInClassInitStyle() == ICIS_ListInit
3482 ? InitializationKind::CreateDirectList(InitExpr->getLocStart())
3483 : InitializationKind::CreateCopy(InitExpr->getLocStart(), InitLoc);
3484 InitializationSequence Seq(*this, Entity, Kind, InitExpr);
3485 Init = Seq.Perform(*this, Entity, Kind, InitExpr);
3486 if (Init.isInvalid()) {
3487 FD->setInvalidDecl();
3492 // C++11 [class.base.init]p7:
3493 // The initialization of each base and member constitutes a
3495 Init = ActOnFinishFullExpr(Init.get(), InitLoc);
3496 if (Init.isInvalid()) {
3497 FD->setInvalidDecl();
3501 InitExpr = Init.get();
3503 FD->setInClassInitializer(InitExpr);
3506 /// \brief Find the direct and/or virtual base specifiers that
3507 /// correspond to the given base type, for use in base initialization
3508 /// within a constructor.
3509 static bool FindBaseInitializer(Sema &SemaRef,
3510 CXXRecordDecl *ClassDecl,
3512 const CXXBaseSpecifier *&DirectBaseSpec,
3513 const CXXBaseSpecifier *&VirtualBaseSpec) {
3514 // First, check for a direct base class.
3515 DirectBaseSpec = nullptr;
3516 for (const auto &Base : ClassDecl->bases()) {
3517 if (SemaRef.Context.hasSameUnqualifiedType(BaseType, Base.getType())) {
3518 // We found a direct base of this type. That's what we're
3520 DirectBaseSpec = &Base;
3525 // Check for a virtual base class.
3526 // FIXME: We might be able to short-circuit this if we know in advance that
3527 // there are no virtual bases.
3528 VirtualBaseSpec = nullptr;
3529 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) {
3530 // We haven't found a base yet; search the class hierarchy for a
3531 // virtual base class.
3532 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
3533 /*DetectVirtual=*/false);
3534 if (SemaRef.IsDerivedFrom(ClassDecl->getLocation(),
3535 SemaRef.Context.getTypeDeclType(ClassDecl),
3537 for (CXXBasePaths::paths_iterator Path = Paths.begin();
3538 Path != Paths.end(); ++Path) {
3539 if (Path->back().Base->isVirtual()) {
3540 VirtualBaseSpec = Path->back().Base;
3547 return DirectBaseSpec || VirtualBaseSpec;
3550 /// \brief Handle a C++ member initializer using braced-init-list syntax.
3552 Sema::ActOnMemInitializer(Decl *ConstructorD,
3555 IdentifierInfo *MemberOrBase,
3556 ParsedType TemplateTypeTy,
3558 SourceLocation IdLoc,
3560 SourceLocation EllipsisLoc) {
3561 return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
3562 DS, IdLoc, InitList,
3566 /// \brief Handle a C++ member initializer using parentheses syntax.
3568 Sema::ActOnMemInitializer(Decl *ConstructorD,
3571 IdentifierInfo *MemberOrBase,
3572 ParsedType TemplateTypeTy,
3574 SourceLocation IdLoc,
3575 SourceLocation LParenLoc,
3576 ArrayRef<Expr *> Args,
3577 SourceLocation RParenLoc,
3578 SourceLocation EllipsisLoc) {
3579 Expr *List = new (Context) ParenListExpr(Context, LParenLoc,
3581 return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
3582 DS, IdLoc, List, EllipsisLoc);
3587 // Callback to only accept typo corrections that can be a valid C++ member
3588 // intializer: either a non-static field member or a base class.
3589 class MemInitializerValidatorCCC : public CorrectionCandidateCallback {
3591 explicit MemInitializerValidatorCCC(CXXRecordDecl *ClassDecl)
3592 : ClassDecl(ClassDecl) {}
3594 bool ValidateCandidate(const TypoCorrection &candidate) override {
3595 if (NamedDecl *ND = candidate.getCorrectionDecl()) {
3596 if (FieldDecl *Member = dyn_cast<FieldDecl>(ND))
3597 return Member->getDeclContext()->getRedeclContext()->Equals(ClassDecl);
3598 return isa<TypeDecl>(ND);
3604 CXXRecordDecl *ClassDecl;
3609 /// \brief Handle a C++ member initializer.
3611 Sema::BuildMemInitializer(Decl *ConstructorD,
3614 IdentifierInfo *MemberOrBase,
3615 ParsedType TemplateTypeTy,
3617 SourceLocation IdLoc,
3619 SourceLocation EllipsisLoc) {
3620 ExprResult Res = CorrectDelayedTyposInExpr(Init);
3621 if (!Res.isUsable())
3628 AdjustDeclIfTemplate(ConstructorD);
3630 CXXConstructorDecl *Constructor
3631 = dyn_cast<CXXConstructorDecl>(ConstructorD);
3633 // The user wrote a constructor initializer on a function that is
3634 // not a C++ constructor. Ignore the error for now, because we may
3635 // have more member initializers coming; we'll diagnose it just
3636 // once in ActOnMemInitializers.
3640 CXXRecordDecl *ClassDecl = Constructor->getParent();
3642 // C++ [class.base.init]p2:
3643 // Names in a mem-initializer-id are looked up in the scope of the
3644 // constructor's class and, if not found in that scope, are looked
3645 // up in the scope containing the constructor's definition.
3646 // [Note: if the constructor's class contains a member with the
3647 // same name as a direct or virtual base class of the class, a
3648 // mem-initializer-id naming the member or base class and composed
3649 // of a single identifier refers to the class member. A
3650 // mem-initializer-id for the hidden base class may be specified
3651 // using a qualified name. ]
3652 if (!SS.getScopeRep() && !TemplateTypeTy) {
3653 // Look for a member, first.
3654 DeclContext::lookup_result Result = ClassDecl->lookup(MemberOrBase);
3655 if (!Result.empty()) {
3657 if ((Member = dyn_cast<FieldDecl>(Result.front())) ||
3658 (Member = dyn_cast<IndirectFieldDecl>(Result.front()))) {
3659 if (EllipsisLoc.isValid())
3660 Diag(EllipsisLoc, diag::err_pack_expansion_member_init)
3662 << SourceRange(IdLoc, Init->getSourceRange().getEnd());
3664 return BuildMemberInitializer(Member, Init, IdLoc);
3668 // It didn't name a member, so see if it names a class.
3670 TypeSourceInfo *TInfo = nullptr;
3672 if (TemplateTypeTy) {
3673 BaseType = GetTypeFromParser(TemplateTypeTy, &TInfo);
3674 } else if (DS.getTypeSpecType() == TST_decltype) {
3675 BaseType = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
3677 LookupResult R(*this, MemberOrBase, IdLoc, LookupOrdinaryName);
3678 LookupParsedName(R, S, &SS);
3680 TypeDecl *TyD = R.getAsSingle<TypeDecl>();
3682 if (R.isAmbiguous()) return true;
3684 // We don't want access-control diagnostics here.
3685 R.suppressDiagnostics();
3687 if (SS.isSet() && isDependentScopeSpecifier(SS)) {
3688 bool NotUnknownSpecialization = false;
3689 DeclContext *DC = computeDeclContext(SS, false);
3690 if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(DC))
3691 NotUnknownSpecialization = !Record->hasAnyDependentBases();
3693 if (!NotUnknownSpecialization) {
3694 // When the scope specifier can refer to a member of an unknown
3695 // specialization, we take it as a type name.
3696 BaseType = CheckTypenameType(ETK_None, SourceLocation(),
3697 SS.getWithLocInContext(Context),
3698 *MemberOrBase, IdLoc);
3699 if (BaseType.isNull())
3703 R.setLookupName(MemberOrBase);
3707 // If no results were found, try to correct typos.
3708 TypoCorrection Corr;
3709 if (R.empty() && BaseType.isNull() &&
3710 (Corr = CorrectTypo(
3711 R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
3712 llvm::make_unique<MemInitializerValidatorCCC>(ClassDecl),
3713 CTK_ErrorRecovery, ClassDecl))) {
3714 if (FieldDecl *Member = Corr.getCorrectionDeclAs<FieldDecl>()) {
3715 // We have found a non-static data member with a similar
3716 // name to what was typed; complain and initialize that
3719 PDiag(diag::err_mem_init_not_member_or_class_suggest)
3720 << MemberOrBase << true);
3721 return BuildMemberInitializer(Member, Init, IdLoc);
3722 } else if (TypeDecl *Type = Corr.getCorrectionDeclAs<TypeDecl>()) {
3723 const CXXBaseSpecifier *DirectBaseSpec;
3724 const CXXBaseSpecifier *VirtualBaseSpec;
3725 if (FindBaseInitializer(*this, ClassDecl,
3726 Context.getTypeDeclType(Type),
3727 DirectBaseSpec, VirtualBaseSpec)) {
3728 // We have found a direct or virtual base class with a
3729 // similar name to what was typed; complain and initialize
3732 PDiag(diag::err_mem_init_not_member_or_class_suggest)
3733 << MemberOrBase << false,
3734 PDiag() /*Suppress note, we provide our own.*/);
3736 const CXXBaseSpecifier *BaseSpec = DirectBaseSpec ? DirectBaseSpec
3738 Diag(BaseSpec->getLocStart(),
3739 diag::note_base_class_specified_here)
3740 << BaseSpec->getType()
3741 << BaseSpec->getSourceRange();
3748 if (!TyD && BaseType.isNull()) {
3749 Diag(IdLoc, diag::err_mem_init_not_member_or_class)
3750 << MemberOrBase << SourceRange(IdLoc,Init->getSourceRange().getEnd());
3755 if (BaseType.isNull()) {
3756 BaseType = Context.getTypeDeclType(TyD);
3757 MarkAnyDeclReferenced(TyD->getLocation(), TyD, /*OdrUse=*/false);
3759 BaseType = Context.getElaboratedType(ETK_None, SS.getScopeRep(),
3761 TInfo = Context.CreateTypeSourceInfo(BaseType);
3762 ElaboratedTypeLoc TL = TInfo->getTypeLoc().castAs<ElaboratedTypeLoc>();
3763 TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IdLoc);
3764 TL.setElaboratedKeywordLoc(SourceLocation());
3765 TL.setQualifierLoc(SS.getWithLocInContext(Context));
3771 TInfo = Context.getTrivialTypeSourceInfo(BaseType, IdLoc);
3773 return BuildBaseInitializer(BaseType, TInfo, Init, ClassDecl, EllipsisLoc);
3776 /// Checks a member initializer expression for cases where reference (or
3777 /// pointer) members are bound to by-value parameters (or their addresses).
3778 static void CheckForDanglingReferenceOrPointer(Sema &S, ValueDecl *Member,
3780 SourceLocation IdLoc) {
3781 QualType MemberTy = Member->getType();
3783 // We only handle pointers and references currently.
3784 // FIXME: Would this be relevant for ObjC object pointers? Or block pointers?
3785 if (!MemberTy->isReferenceType() && !MemberTy->isPointerType())
3788 const bool IsPointer = MemberTy->isPointerType();
3790 if (const UnaryOperator *Op
3791 = dyn_cast<UnaryOperator>(Init->IgnoreParenImpCasts())) {
3792 // The only case we're worried about with pointers requires taking the
3794 if (Op->getOpcode() != UO_AddrOf)
3797 Init = Op->getSubExpr();
3799 // We only handle address-of expression initializers for pointers.
3804 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Init->IgnoreParens())) {
3805 // We only warn when referring to a non-reference parameter declaration.
3806 const ParmVarDecl *Parameter = dyn_cast<ParmVarDecl>(DRE->getDecl());
3807 if (!Parameter || Parameter->getType()->isReferenceType())
3810 S.Diag(Init->getExprLoc(),
3811 IsPointer ? diag::warn_init_ptr_member_to_parameter_addr
3812 : diag::warn_bind_ref_member_to_parameter)
3813 << Member << Parameter << Init->getSourceRange();
3815 // Other initializers are fine.
3819 S.Diag(Member->getLocation(), diag::note_ref_or_ptr_member_declared_here)
3820 << (unsigned)IsPointer;
3824 Sema::BuildMemberInitializer(ValueDecl *Member, Expr *Init,
3825 SourceLocation IdLoc) {
3826 FieldDecl *DirectMember = dyn_cast<FieldDecl>(Member);
3827 IndirectFieldDecl *IndirectMember = dyn_cast<IndirectFieldDecl>(Member);
3828 assert((DirectMember || IndirectMember) &&
3829 "Member must be a FieldDecl or IndirectFieldDecl");
3831 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
3834 if (Member->isInvalidDecl())
3838 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
3839 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
3840 } else if (InitListExpr *InitList = dyn_cast<InitListExpr>(Init)) {
3841 Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
3843 // Template instantiation doesn't reconstruct ParenListExprs for us.
3847 SourceRange InitRange = Init->getSourceRange();
3849 if (Member->getType()->isDependentType() || Init->isTypeDependent()) {
3850 // Can't check initialization for a member of dependent type or when
3851 // any of the arguments are type-dependent expressions.
3852 DiscardCleanupsInEvaluationContext();
3854 bool InitList = false;
3855 if (isa<InitListExpr>(Init)) {
3860 // Initialize the member.
3861 InitializedEntity MemberEntity =
3862 DirectMember ? InitializedEntity::InitializeMember(DirectMember, nullptr)
3863 : InitializedEntity::InitializeMember(IndirectMember,
3865 InitializationKind Kind =
3866 InitList ? InitializationKind::CreateDirectList(IdLoc)
3867 : InitializationKind::CreateDirect(IdLoc, InitRange.getBegin(),
3868 InitRange.getEnd());
3870 InitializationSequence InitSeq(*this, MemberEntity, Kind, Args);
3871 ExprResult MemberInit = InitSeq.Perform(*this, MemberEntity, Kind, Args,
3873 if (MemberInit.isInvalid())
3876 CheckForDanglingReferenceOrPointer(*this, Member, MemberInit.get(), IdLoc);
3878 // C++11 [class.base.init]p7:
3879 // The initialization of each base and member constitutes a
3881 MemberInit = ActOnFinishFullExpr(MemberInit.get(), InitRange.getBegin());
3882 if (MemberInit.isInvalid())
3885 Init = MemberInit.get();
3889 return new (Context) CXXCtorInitializer(Context, DirectMember, IdLoc,
3890 InitRange.getBegin(), Init,
3891 InitRange.getEnd());
3893 return new (Context) CXXCtorInitializer(Context, IndirectMember, IdLoc,
3894 InitRange.getBegin(), Init,
3895 InitRange.getEnd());
3900 Sema::BuildDelegatingInitializer(TypeSourceInfo *TInfo, Expr *Init,
3901 CXXRecordDecl *ClassDecl) {
3902 SourceLocation NameLoc = TInfo->getTypeLoc().getLocalSourceRange().getBegin();
3903 if (!LangOpts.CPlusPlus11)
3904 return Diag(NameLoc, diag::err_delegating_ctor)
3905 << TInfo->getTypeLoc().getLocalSourceRange();
3906 Diag(NameLoc, diag::warn_cxx98_compat_delegating_ctor);
3908 bool InitList = true;
3909 MultiExprArg Args = Init;
3910 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
3912 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
3915 SourceRange InitRange = Init->getSourceRange();
3916 // Initialize the object.
3917 InitializedEntity DelegationEntity = InitializedEntity::InitializeDelegation(
3918 QualType(ClassDecl->getTypeForDecl(), 0));
3919 InitializationKind Kind =
3920 InitList ? InitializationKind::CreateDirectList(NameLoc)
3921 : InitializationKind::CreateDirect(NameLoc, InitRange.getBegin(),
3922 InitRange.getEnd());
3923 InitializationSequence InitSeq(*this, DelegationEntity, Kind, Args);
3924 ExprResult DelegationInit = InitSeq.Perform(*this, DelegationEntity, Kind,
3926 if (DelegationInit.isInvalid())
3929 assert(cast<CXXConstructExpr>(DelegationInit.get())->getConstructor() &&
3930 "Delegating constructor with no target?");
3932 // C++11 [class.base.init]p7:
3933 // The initialization of each base and member constitutes a
3935 DelegationInit = ActOnFinishFullExpr(DelegationInit.get(),
3936 InitRange.getBegin());
3937 if (DelegationInit.isInvalid())
3940 // If we are in a dependent context, template instantiation will
3941 // perform this type-checking again. Just save the arguments that we
3942 // received in a ParenListExpr.
3943 // FIXME: This isn't quite ideal, since our ASTs don't capture all
3944 // of the information that we have about the base
3945 // initializer. However, deconstructing the ASTs is a dicey process,
3946 // and this approach is far more likely to get the corner cases right.
3947 if (CurContext->isDependentContext())
3948 DelegationInit = Init;
3950 return new (Context) CXXCtorInitializer(Context, TInfo, InitRange.getBegin(),
3951 DelegationInit.getAs<Expr>(),
3952 InitRange.getEnd());
3956 Sema::BuildBaseInitializer(QualType BaseType, TypeSourceInfo *BaseTInfo,
3957 Expr *Init, CXXRecordDecl *ClassDecl,
3958 SourceLocation EllipsisLoc) {
3959 SourceLocation BaseLoc
3960 = BaseTInfo->getTypeLoc().getLocalSourceRange().getBegin();
3962 if (!BaseType->isDependentType() && !BaseType->isRecordType())
3963 return Diag(BaseLoc, diag::err_base_init_does_not_name_class)
3964 << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
3966 // C++ [class.base.init]p2:
3967 // [...] Unless the mem-initializer-id names a nonstatic data
3968 // member of the constructor's class or a direct or virtual base
3969 // of that class, the mem-initializer is ill-formed. A
3970 // mem-initializer-list can initialize a base class using any
3971 // name that denotes that base class type.
3972 bool Dependent = BaseType->isDependentType() || Init->isTypeDependent();
3974 SourceRange InitRange = Init->getSourceRange();
3975 if (EllipsisLoc.isValid()) {
3976 // This is a pack expansion.
3977 if (!BaseType->containsUnexpandedParameterPack()) {
3978 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
3979 << SourceRange(BaseLoc, InitRange.getEnd());
3981 EllipsisLoc = SourceLocation();
3984 // Check for any unexpanded parameter packs.
3985 if (DiagnoseUnexpandedParameterPack(BaseLoc, BaseTInfo, UPPC_Initializer))
3988 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
3992 // Check for direct and virtual base classes.
3993 const CXXBaseSpecifier *DirectBaseSpec = nullptr;
3994 const CXXBaseSpecifier *VirtualBaseSpec = nullptr;
3996 if (Context.hasSameUnqualifiedType(QualType(ClassDecl->getTypeForDecl(),0),
3998 return BuildDelegatingInitializer(BaseTInfo, Init, ClassDecl);
4000 FindBaseInitializer(*this, ClassDecl, BaseType, DirectBaseSpec,
4003 // C++ [base.class.init]p2:
4004 // Unless the mem-initializer-id names a nonstatic data member of the
4005 // constructor's class or a direct or virtual base of that class, the
4006 // mem-initializer is ill-formed.
4007 if (!DirectBaseSpec && !VirtualBaseSpec) {
4008 // If the class has any dependent bases, then it's possible that
4009 // one of those types will resolve to the same type as
4010 // BaseType. Therefore, just treat this as a dependent base
4011 // class initialization. FIXME: Should we try to check the
4012 // initialization anyway? It seems odd.
4013 if (ClassDecl->hasAnyDependentBases())
4016 return Diag(BaseLoc, diag::err_not_direct_base_or_virtual)
4017 << BaseType << Context.getTypeDeclType(ClassDecl)
4018 << BaseTInfo->getTypeLoc().getLocalSourceRange();
4023 DiscardCleanupsInEvaluationContext();
4025 return new (Context) CXXCtorInitializer(Context, BaseTInfo,
4026 /*IsVirtual=*/false,
4027 InitRange.getBegin(), Init,
4028 InitRange.getEnd(), EllipsisLoc);
4031 // C++ [base.class.init]p2:
4032 // If a mem-initializer-id is ambiguous because it designates both
4033 // a direct non-virtual base class and an inherited virtual base
4034 // class, the mem-initializer is ill-formed.
4035 if (DirectBaseSpec && VirtualBaseSpec)
4036 return Diag(BaseLoc, diag::err_base_init_direct_and_virtual)
4037 << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
4039 const CXXBaseSpecifier *BaseSpec = DirectBaseSpec;
4041 BaseSpec = VirtualBaseSpec;
4043 // Initialize the base.
4044 bool InitList = true;
4045 MultiExprArg Args = Init;
4046 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4048 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4051 InitializedEntity BaseEntity =
4052 InitializedEntity::InitializeBase(Context, BaseSpec, VirtualBaseSpec);
4053 InitializationKind Kind =
4054 InitList ? InitializationKind::CreateDirectList(BaseLoc)
4055 : InitializationKind::CreateDirect(BaseLoc, InitRange.getBegin(),
4056 InitRange.getEnd());
4057 InitializationSequence InitSeq(*this, BaseEntity, Kind, Args);
4058 ExprResult BaseInit = InitSeq.Perform(*this, BaseEntity, Kind, Args, nullptr);
4059 if (BaseInit.isInvalid())
4062 // C++11 [class.base.init]p7:
4063 // The initialization of each base and member constitutes a
4065 BaseInit = ActOnFinishFullExpr(BaseInit.get(), InitRange.getBegin());
4066 if (BaseInit.isInvalid())
4069 // If we are in a dependent context, template instantiation will
4070 // perform this type-checking again. Just save the arguments that we
4071 // received in a ParenListExpr.
4072 // FIXME: This isn't quite ideal, since our ASTs don't capture all
4073 // of the information that we have about the base
4074 // initializer. However, deconstructing the ASTs is a dicey process,
4075 // and this approach is far more likely to get the corner cases right.
4076 if (CurContext->isDependentContext())
4079 return new (Context) CXXCtorInitializer(Context, BaseTInfo,
4080 BaseSpec->isVirtual(),
4081 InitRange.getBegin(),
4082 BaseInit.getAs<Expr>(),
4083 InitRange.getEnd(), EllipsisLoc);
4086 // Create a static_cast\<T&&>(expr).
4087 static Expr *CastForMoving(Sema &SemaRef, Expr *E, QualType T = QualType()) {
4088 if (T.isNull()) T = E->getType();
4089 QualType TargetType = SemaRef.BuildReferenceType(
4090 T, /*SpelledAsLValue*/false, SourceLocation(), DeclarationName());
4091 SourceLocation ExprLoc = E->getLocStart();
4092 TypeSourceInfo *TargetLoc = SemaRef.Context.getTrivialTypeSourceInfo(
4093 TargetType, ExprLoc);
4095 return SemaRef.BuildCXXNamedCast(ExprLoc, tok::kw_static_cast, TargetLoc, E,
4096 SourceRange(ExprLoc, ExprLoc),
4097 E->getSourceRange()).get();
4100 /// ImplicitInitializerKind - How an implicit base or member initializer should
4101 /// initialize its base or member.
4102 enum ImplicitInitializerKind {
4110 BuildImplicitBaseInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
4111 ImplicitInitializerKind ImplicitInitKind,
4112 CXXBaseSpecifier *BaseSpec,
4113 bool IsInheritedVirtualBase,
4114 CXXCtorInitializer *&CXXBaseInit) {
4115 InitializedEntity InitEntity
4116 = InitializedEntity::InitializeBase(SemaRef.Context, BaseSpec,
4117 IsInheritedVirtualBase);
4119 ExprResult BaseInit;
4121 switch (ImplicitInitKind) {
4124 InitializationKind InitKind
4125 = InitializationKind::CreateDefault(Constructor->getLocation());
4126 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
4127 BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
4133 bool Moving = ImplicitInitKind == IIK_Move;
4134 ParmVarDecl *Param = Constructor->getParamDecl(0);
4135 QualType ParamType = Param->getType().getNonReferenceType();
4138 DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
4139 SourceLocation(), Param, false,
4140 Constructor->getLocation(), ParamType,
4141 VK_LValue, nullptr);
4143 SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(CopyCtorArg));
4145 // Cast to the base class to avoid ambiguities.
4147 SemaRef.Context.getQualifiedType(BaseSpec->getType().getUnqualifiedType(),
4148 ParamType.getQualifiers());
4151 CopyCtorArg = CastForMoving(SemaRef, CopyCtorArg);
4154 CXXCastPath BasePath;
4155 BasePath.push_back(BaseSpec);
4156 CopyCtorArg = SemaRef.ImpCastExprToType(CopyCtorArg, ArgTy,
4157 CK_UncheckedDerivedToBase,
4158 Moving ? VK_XValue : VK_LValue,
4161 InitializationKind InitKind
4162 = InitializationKind::CreateDirect(Constructor->getLocation(),
4163 SourceLocation(), SourceLocation());
4164 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, CopyCtorArg);
4165 BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, CopyCtorArg);
4170 BaseInit = SemaRef.MaybeCreateExprWithCleanups(BaseInit);
4171 if (BaseInit.isInvalid())
4175 new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4176 SemaRef.Context.getTrivialTypeSourceInfo(BaseSpec->getType(),
4178 BaseSpec->isVirtual(),
4180 BaseInit.getAs<Expr>(),
4187 static bool RefersToRValueRef(Expr *MemRef) {
4188 ValueDecl *Referenced = cast<MemberExpr>(MemRef)->getMemberDecl();
4189 return Referenced->getType()->isRValueReferenceType();
4193 BuildImplicitMemberInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
4194 ImplicitInitializerKind ImplicitInitKind,
4195 FieldDecl *Field, IndirectFieldDecl *Indirect,
4196 CXXCtorInitializer *&CXXMemberInit) {
4197 if (Field->isInvalidDecl())
4200 SourceLocation Loc = Constructor->getLocation();
4202 if (ImplicitInitKind == IIK_Copy || ImplicitInitKind == IIK_Move) {
4203 bool Moving = ImplicitInitKind == IIK_Move;
4204 ParmVarDecl *Param = Constructor->getParamDecl(0);
4205 QualType ParamType = Param->getType().getNonReferenceType();
4207 // Suppress copying zero-width bitfields.
4208 if (Field->isBitField() && Field->getBitWidthValue(SemaRef.Context) == 0)
4211 Expr *MemberExprBase =
4212 DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
4213 SourceLocation(), Param, false,
4214 Loc, ParamType, VK_LValue, nullptr);
4216 SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(MemberExprBase));
4219 MemberExprBase = CastForMoving(SemaRef, MemberExprBase);
4222 // Build a reference to this field within the parameter.
4224 LookupResult MemberLookup(SemaRef, Field->getDeclName(), Loc,
4225 Sema::LookupMemberName);
4226 MemberLookup.addDecl(Indirect ? cast<ValueDecl>(Indirect)
4227 : cast<ValueDecl>(Field), AS_public);
4228 MemberLookup.resolveKind();
4230 = SemaRef.BuildMemberReferenceExpr(MemberExprBase,
4234 /*TemplateKWLoc=*/SourceLocation(),
4235 /*FirstQualifierInScope=*/nullptr,
4237 /*TemplateArgs=*/nullptr,
4239 if (CtorArg.isInvalid())
4242 // C++11 [class.copy]p15:
4243 // - if a member m has rvalue reference type T&&, it is direct-initialized
4244 // with static_cast<T&&>(x.m);
4245 if (RefersToRValueRef(CtorArg.get())) {
4246 CtorArg = CastForMoving(SemaRef, CtorArg.get());
4249 InitializedEntity Entity =
4250 Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
4252 : InitializedEntity::InitializeMember(Field, nullptr,
4255 // Direct-initialize to use the copy constructor.
4256 InitializationKind InitKind =
4257 InitializationKind::CreateDirect(Loc, SourceLocation(), SourceLocation());
4259 Expr *CtorArgE = CtorArg.getAs<Expr>();
4260 InitializationSequence InitSeq(SemaRef, Entity, InitKind, CtorArgE);
4261 ExprResult MemberInit =
4262 InitSeq.Perform(SemaRef, Entity, InitKind, MultiExprArg(&CtorArgE, 1));
4263 MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
4264 if (MemberInit.isInvalid())
4268 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
4269 SemaRef.Context, Indirect, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
4271 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
4272 SemaRef.Context, Field, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
4276 assert((ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) &&
4277 "Unhandled implicit init kind!");
4279 QualType FieldBaseElementType =
4280 SemaRef.Context.getBaseElementType(Field->getType());
4282 if (FieldBaseElementType->isRecordType()) {
4283 InitializedEntity InitEntity =
4284 Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
4286 : InitializedEntity::InitializeMember(Field, nullptr,
4288 InitializationKind InitKind =
4289 InitializationKind::CreateDefault(Loc);
4291 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
4292 ExprResult MemberInit =
4293 InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
4295 MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
4296 if (MemberInit.isInvalid())
4300 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4306 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4313 if (!Field->getParent()->isUnion()) {
4314 if (FieldBaseElementType->isReferenceType()) {
4315 SemaRef.Diag(Constructor->getLocation(),
4316 diag::err_uninitialized_member_in_ctor)
4317 << (int)Constructor->isImplicit()
4318 << SemaRef.Context.getTagDeclType(Constructor->getParent())
4319 << 0 << Field->getDeclName();
4320 SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
4324 if (FieldBaseElementType.isConstQualified()) {
4325 SemaRef.Diag(Constructor->getLocation(),
4326 diag::err_uninitialized_member_in_ctor)
4327 << (int)Constructor->isImplicit()
4328 << SemaRef.Context.getTagDeclType(Constructor->getParent())
4329 << 1 << Field->getDeclName();
4330 SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
4335 if (SemaRef.getLangOpts().ObjCAutoRefCount &&
4336 FieldBaseElementType->isObjCRetainableType() &&
4337 FieldBaseElementType.getObjCLifetime() != Qualifiers::OCL_None &&
4338 FieldBaseElementType.getObjCLifetime() != Qualifiers::OCL_ExplicitNone) {
4340 // Default-initialize Objective-C pointers to NULL.
4342 = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Field,
4344 new (SemaRef.Context) ImplicitValueInitExpr(Field->getType()),
4349 // Nothing to initialize.
4350 CXXMemberInit = nullptr;
4355 struct BaseAndFieldInfo {
4357 CXXConstructorDecl *Ctor;
4358 bool AnyErrorsInInits;
4359 ImplicitInitializerKind IIK;
4360 llvm::DenseMap<const void *, CXXCtorInitializer*> AllBaseFields;
4361 SmallVector<CXXCtorInitializer*, 8> AllToInit;
4362 llvm::DenseMap<TagDecl*, FieldDecl*> ActiveUnionMember;
4364 BaseAndFieldInfo(Sema &S, CXXConstructorDecl *Ctor, bool ErrorsInInits)
4365 : S(S), Ctor(Ctor), AnyErrorsInInits(ErrorsInInits) {
4366 bool Generated = Ctor->isImplicit() || Ctor->isDefaulted();
4367 if (Ctor->getInheritedConstructor())
4369 else if (Generated && Ctor->isCopyConstructor())
4371 else if (Generated && Ctor->isMoveConstructor())
4377 bool isImplicitCopyOrMove() const {
4388 llvm_unreachable("Invalid ImplicitInitializerKind!");
4391 bool addFieldInitializer(CXXCtorInitializer *Init) {
4392 AllToInit.push_back(Init);
4394 // Check whether this initializer makes the field "used".
4395 if (Init->getInit()->HasSideEffects(S.Context))
4396 S.UnusedPrivateFields.remove(Init->getAnyMember());
4401 bool isInactiveUnionMember(FieldDecl *Field) {
4402 RecordDecl *Record = Field->getParent();
4403 if (!Record->isUnion())
4406 if (FieldDecl *Active =
4407 ActiveUnionMember.lookup(Record->getCanonicalDecl()))
4408 return Active != Field->getCanonicalDecl();
4410 // In an implicit copy or move constructor, ignore any in-class initializer.
4411 if (isImplicitCopyOrMove())
4414 // If there's no explicit initialization, the field is active only if it
4415 // has an in-class initializer...
4416 if (Field->hasInClassInitializer())
4418 // ... or it's an anonymous struct or union whose class has an in-class
4420 if (!Field->isAnonymousStructOrUnion())
4422 CXXRecordDecl *FieldRD = Field->getType()->getAsCXXRecordDecl();
4423 return !FieldRD->hasInClassInitializer();
4426 /// \brief Determine whether the given field is, or is within, a union member
4427 /// that is inactive (because there was an initializer given for a different
4428 /// member of the union, or because the union was not initialized at all).
4429 bool isWithinInactiveUnionMember(FieldDecl *Field,
4430 IndirectFieldDecl *Indirect) {
4432 return isInactiveUnionMember(Field);
4434 for (auto *C : Indirect->chain()) {
4435 FieldDecl *Field = dyn_cast<FieldDecl>(C);
4436 if (Field && isInactiveUnionMember(Field))
4444 /// \brief Determine whether the given type is an incomplete or zero-lenfgth
4446 static bool isIncompleteOrZeroLengthArrayType(ASTContext &Context, QualType T) {
4447 if (T->isIncompleteArrayType())
4450 while (const ConstantArrayType *ArrayT = Context.getAsConstantArrayType(T)) {
4451 if (!ArrayT->getSize())
4454 T = ArrayT->getElementType();
4460 static bool CollectFieldInitializer(Sema &SemaRef, BaseAndFieldInfo &Info,
4462 IndirectFieldDecl *Indirect = nullptr) {
4463 if (Field->isInvalidDecl())
4466 // Overwhelmingly common case: we have a direct initializer for this field.
4467 if (CXXCtorInitializer *Init =
4468 Info.AllBaseFields.lookup(Field->getCanonicalDecl()))
4469 return Info.addFieldInitializer(Init);
4471 // C++11 [class.base.init]p8:
4472 // if the entity is a non-static data member that has a
4473 // brace-or-equal-initializer and either
4474 // -- the constructor's class is a union and no other variant member of that
4475 // union is designated by a mem-initializer-id or
4476 // -- the constructor's class is not a union, and, if the entity is a member
4477 // of an anonymous union, no other member of that union is designated by
4478 // a mem-initializer-id,
4479 // the entity is initialized as specified in [dcl.init].
4481 // We also apply the same rules to handle anonymous structs within anonymous
4483 if (Info.isWithinInactiveUnionMember(Field, Indirect))
4486 if (Field->hasInClassInitializer() && !Info.isImplicitCopyOrMove()) {
4488 SemaRef.BuildCXXDefaultInitExpr(Info.Ctor->getLocation(), Field);
4489 if (DIE.isInvalid())
4491 CXXCtorInitializer *Init;
4493 Init = new (SemaRef.Context)
4494 CXXCtorInitializer(SemaRef.Context, Indirect, SourceLocation(),
4495 SourceLocation(), DIE.get(), SourceLocation());
4497 Init = new (SemaRef.Context)
4498 CXXCtorInitializer(SemaRef.Context, Field, SourceLocation(),
4499 SourceLocation(), DIE.get(), SourceLocation());
4500 return Info.addFieldInitializer(Init);
4503 // Don't initialize incomplete or zero-length arrays.
4504 if (isIncompleteOrZeroLengthArrayType(SemaRef.Context, Field->getType()))
4507 // Don't try to build an implicit initializer if there were semantic
4508 // errors in any of the initializers (and therefore we might be
4509 // missing some that the user actually wrote).
4510 if (Info.AnyErrorsInInits)
4513 CXXCtorInitializer *Init = nullptr;
4514 if (BuildImplicitMemberInitializer(Info.S, Info.Ctor, Info.IIK, Field,
4521 return Info.addFieldInitializer(Init);
4525 Sema::SetDelegatingInitializer(CXXConstructorDecl *Constructor,
4526 CXXCtorInitializer *Initializer) {
4527 assert(Initializer->isDelegatingInitializer());
4528 Constructor->setNumCtorInitializers(1);
4529 CXXCtorInitializer **initializer =
4530 new (Context) CXXCtorInitializer*[1];
4531 memcpy(initializer, &Initializer, sizeof (CXXCtorInitializer*));
4532 Constructor->setCtorInitializers(initializer);
4534 if (CXXDestructorDecl *Dtor = LookupDestructor(Constructor->getParent())) {
4535 MarkFunctionReferenced(Initializer->getSourceLocation(), Dtor);
4536 DiagnoseUseOfDecl(Dtor, Initializer->getSourceLocation());
4539 DelegatingCtorDecls.push_back(Constructor);
4541 DiagnoseUninitializedFields(*this, Constructor);
4546 bool Sema::SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
4547 ArrayRef<CXXCtorInitializer *> Initializers) {
4548 if (Constructor->isDependentContext()) {
4549 // Just store the initializers as written, they will be checked during
4551 if (!Initializers.empty()) {
4552 Constructor->setNumCtorInitializers(Initializers.size());
4553 CXXCtorInitializer **baseOrMemberInitializers =
4554 new (Context) CXXCtorInitializer*[Initializers.size()];
4555 memcpy(baseOrMemberInitializers, Initializers.data(),
4556 Initializers.size() * sizeof(CXXCtorInitializer*));
4557 Constructor->setCtorInitializers(baseOrMemberInitializers);
4560 // Let template instantiation know whether we had errors.
4562 Constructor->setInvalidDecl();
4567 BaseAndFieldInfo Info(*this, Constructor, AnyErrors);
4569 // We need to build the initializer AST according to order of construction
4570 // and not what user specified in the Initializers list.
4571 CXXRecordDecl *ClassDecl = Constructor->getParent()->getDefinition();
4575 bool HadError = false;
4577 for (unsigned i = 0; i < Initializers.size(); i++) {
4578 CXXCtorInitializer *Member = Initializers[i];
4580 if (Member->isBaseInitializer())
4581 Info.AllBaseFields[Member->getBaseClass()->getAs<RecordType>()] = Member;
4583 Info.AllBaseFields[Member->getAnyMember()->getCanonicalDecl()] = Member;
4585 if (IndirectFieldDecl *F = Member->getIndirectMember()) {
4586 for (auto *C : F->chain()) {
4587 FieldDecl *FD = dyn_cast<FieldDecl>(C);
4588 if (FD && FD->getParent()->isUnion())
4589 Info.ActiveUnionMember.insert(std::make_pair(
4590 FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
4592 } else if (FieldDecl *FD = Member->getMember()) {
4593 if (FD->getParent()->isUnion())
4594 Info.ActiveUnionMember.insert(std::make_pair(
4595 FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
4600 // Keep track of the direct virtual bases.
4601 llvm::SmallPtrSet<CXXBaseSpecifier *, 16> DirectVBases;
4602 for (auto &I : ClassDecl->bases()) {
4604 DirectVBases.insert(&I);
4607 // Push virtual bases before others.
4608 for (auto &VBase : ClassDecl->vbases()) {
4609 if (CXXCtorInitializer *Value
4610 = Info.AllBaseFields.lookup(VBase.getType()->getAs<RecordType>())) {
4611 // [class.base.init]p7, per DR257:
4612 // A mem-initializer where the mem-initializer-id names a virtual base
4613 // class is ignored during execution of a constructor of any class that
4614 // is not the most derived class.
4615 if (ClassDecl->isAbstract()) {
4616 // FIXME: Provide a fixit to remove the base specifier. This requires
4617 // tracking the location of the associated comma for a base specifier.
4618 Diag(Value->getSourceLocation(), diag::warn_abstract_vbase_init_ignored)
4619 << VBase.getType() << ClassDecl;
4620 DiagnoseAbstractType(ClassDecl);
4623 Info.AllToInit.push_back(Value);
4624 } else if (!AnyErrors && !ClassDecl->isAbstract()) {
4625 // [class.base.init]p8, per DR257:
4626 // If a given [...] base class is not named by a mem-initializer-id
4627 // [...] and the entity is not a virtual base class of an abstract
4628 // class, then [...] the entity is default-initialized.
4629 bool IsInheritedVirtualBase = !DirectVBases.count(&VBase);
4630 CXXCtorInitializer *CXXBaseInit;
4631 if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
4632 &VBase, IsInheritedVirtualBase,
4638 Info.AllToInit.push_back(CXXBaseInit);
4642 // Non-virtual bases.
4643 for (auto &Base : ClassDecl->bases()) {
4644 // Virtuals are in the virtual base list and already constructed.
4645 if (Base.isVirtual())
4648 if (CXXCtorInitializer *Value
4649 = Info.AllBaseFields.lookup(Base.getType()->getAs<RecordType>())) {
4650 Info.AllToInit.push_back(Value);
4651 } else if (!AnyErrors) {
4652 CXXCtorInitializer *CXXBaseInit;
4653 if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
4654 &Base, /*IsInheritedVirtualBase=*/false,
4660 Info.AllToInit.push_back(CXXBaseInit);
4665 for (auto *Mem : ClassDecl->decls()) {
4666 if (auto *F = dyn_cast<FieldDecl>(Mem)) {
4667 // C++ [class.bit]p2:
4668 // A declaration for a bit-field that omits the identifier declares an
4669 // unnamed bit-field. Unnamed bit-fields are not members and cannot be
4671 if (F->isUnnamedBitfield())
4674 // If we're not generating the implicit copy/move constructor, then we'll
4675 // handle anonymous struct/union fields based on their individual
4677 if (F->isAnonymousStructOrUnion() && !Info.isImplicitCopyOrMove())
4680 if (CollectFieldInitializer(*this, Info, F))
4685 // Beyond this point, we only consider default initialization.
4686 if (Info.isImplicitCopyOrMove())
4689 if (auto *F = dyn_cast<IndirectFieldDecl>(Mem)) {
4690 if (F->getType()->isIncompleteArrayType()) {
4691 assert(ClassDecl->hasFlexibleArrayMember() &&
4692 "Incomplete array type is not valid");
4696 // Initialize each field of an anonymous struct individually.
4697 if (CollectFieldInitializer(*this, Info, F->getAnonField(), F))
4704 unsigned NumInitializers = Info.AllToInit.size();
4705 if (NumInitializers > 0) {
4706 Constructor->setNumCtorInitializers(NumInitializers);
4707 CXXCtorInitializer **baseOrMemberInitializers =
4708 new (Context) CXXCtorInitializer*[NumInitializers];
4709 memcpy(baseOrMemberInitializers, Info.AllToInit.data(),
4710 NumInitializers * sizeof(CXXCtorInitializer*));
4711 Constructor->setCtorInitializers(baseOrMemberInitializers);
4713 // Constructors implicitly reference the base and member
4715 MarkBaseAndMemberDestructorsReferenced(Constructor->getLocation(),
4716 Constructor->getParent());
4722 static void PopulateKeysForFields(FieldDecl *Field, SmallVectorImpl<const void*> &IdealInits) {
4723 if (const RecordType *RT = Field->getType()->getAs<RecordType>()) {
4724 const RecordDecl *RD = RT->getDecl();
4725 if (RD->isAnonymousStructOrUnion()) {
4726 for (auto *Field : RD->fields())
4727 PopulateKeysForFields(Field, IdealInits);
4731 IdealInits.push_back(Field->getCanonicalDecl());
4734 static const void *GetKeyForBase(ASTContext &Context, QualType BaseType) {
4735 return Context.getCanonicalType(BaseType).getTypePtr();
4738 static const void *GetKeyForMember(ASTContext &Context,
4739 CXXCtorInitializer *Member) {
4740 if (!Member->isAnyMemberInitializer())
4741 return GetKeyForBase(Context, QualType(Member->getBaseClass(), 0));
4743 return Member->getAnyMember()->getCanonicalDecl();
4746 static void DiagnoseBaseOrMemInitializerOrder(
4747 Sema &SemaRef, const CXXConstructorDecl *Constructor,
4748 ArrayRef<CXXCtorInitializer *> Inits) {
4749 if (Constructor->getDeclContext()->isDependentContext())
4752 // Don't check initializers order unless the warning is enabled at the
4753 // location of at least one initializer.
4754 bool ShouldCheckOrder = false;
4755 for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
4756 CXXCtorInitializer *Init = Inits[InitIndex];
4757 if (!SemaRef.Diags.isIgnored(diag::warn_initializer_out_of_order,
4758 Init->getSourceLocation())) {
4759 ShouldCheckOrder = true;
4763 if (!ShouldCheckOrder)
4766 // Build the list of bases and members in the order that they'll
4767 // actually be initialized. The explicit initializers should be in
4768 // this same order but may be missing things.
4769 SmallVector<const void*, 32> IdealInitKeys;
4771 const CXXRecordDecl *ClassDecl = Constructor->getParent();
4773 // 1. Virtual bases.
4774 for (const auto &VBase : ClassDecl->vbases())
4775 IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, VBase.getType()));
4777 // 2. Non-virtual bases.
4778 for (const auto &Base : ClassDecl->bases()) {
4779 if (Base.isVirtual())
4781 IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, Base.getType()));
4784 // 3. Direct fields.
4785 for (auto *Field : ClassDecl->fields()) {
4786 if (Field->isUnnamedBitfield())
4789 PopulateKeysForFields(Field, IdealInitKeys);
4792 unsigned NumIdealInits = IdealInitKeys.size();
4793 unsigned IdealIndex = 0;
4795 CXXCtorInitializer *PrevInit = nullptr;
4796 for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
4797 CXXCtorInitializer *Init = Inits[InitIndex];
4798 const void *InitKey = GetKeyForMember(SemaRef.Context, Init);
4800 // Scan forward to try to find this initializer in the idealized
4801 // initializers list.
4802 for (; IdealIndex != NumIdealInits; ++IdealIndex)
4803 if (InitKey == IdealInitKeys[IdealIndex])
4806 // If we didn't find this initializer, it must be because we
4807 // scanned past it on a previous iteration. That can only
4808 // happen if we're out of order; emit a warning.
4809 if (IdealIndex == NumIdealInits && PrevInit) {
4810 Sema::SemaDiagnosticBuilder D =
4811 SemaRef.Diag(PrevInit->getSourceLocation(),
4812 diag::warn_initializer_out_of_order);
4814 if (PrevInit->isAnyMemberInitializer())
4815 D << 0 << PrevInit->getAnyMember()->getDeclName();
4817 D << 1 << PrevInit->getTypeSourceInfo()->getType();
4819 if (Init->isAnyMemberInitializer())
4820 D << 0 << Init->getAnyMember()->getDeclName();
4822 D << 1 << Init->getTypeSourceInfo()->getType();
4824 // Move back to the initializer's location in the ideal list.
4825 for (IdealIndex = 0; IdealIndex != NumIdealInits; ++IdealIndex)
4826 if (InitKey == IdealInitKeys[IdealIndex])
4829 assert(IdealIndex < NumIdealInits &&
4830 "initializer not found in initializer list");
4838 bool CheckRedundantInit(Sema &S,
4839 CXXCtorInitializer *Init,
4840 CXXCtorInitializer *&PrevInit) {
4846 if (FieldDecl *Field = Init->getAnyMember())
4847 S.Diag(Init->getSourceLocation(),
4848 diag::err_multiple_mem_initialization)
4849 << Field->getDeclName()
4850 << Init->getSourceRange();
4852 const Type *BaseClass = Init->getBaseClass();
4853 assert(BaseClass && "neither field nor base");
4854 S.Diag(Init->getSourceLocation(),
4855 diag::err_multiple_base_initialization)
4856 << QualType(BaseClass, 0)
4857 << Init->getSourceRange();
4859 S.Diag(PrevInit->getSourceLocation(), diag::note_previous_initializer)
4860 << 0 << PrevInit->getSourceRange();
4865 typedef std::pair<NamedDecl *, CXXCtorInitializer *> UnionEntry;
4866 typedef llvm::DenseMap<RecordDecl*, UnionEntry> RedundantUnionMap;
4868 bool CheckRedundantUnionInit(Sema &S,
4869 CXXCtorInitializer *Init,
4870 RedundantUnionMap &Unions) {
4871 FieldDecl *Field = Init->getAnyMember();
4872 RecordDecl *Parent = Field->getParent();
4873 NamedDecl *Child = Field;
4875 while (Parent->isAnonymousStructOrUnion() || Parent->isUnion()) {
4876 if (Parent->isUnion()) {
4877 UnionEntry &En = Unions[Parent];
4878 if (En.first && En.first != Child) {
4879 S.Diag(Init->getSourceLocation(),
4880 diag::err_multiple_mem_union_initialization)
4881 << Field->getDeclName()
4882 << Init->getSourceRange();
4883 S.Diag(En.second->getSourceLocation(), diag::note_previous_initializer)
4884 << 0 << En.second->getSourceRange();
4891 if (!Parent->isAnonymousStructOrUnion())
4896 Parent = cast<RecordDecl>(Parent->getDeclContext());
4903 /// ActOnMemInitializers - Handle the member initializers for a constructor.
4904 void Sema::ActOnMemInitializers(Decl *ConstructorDecl,
4905 SourceLocation ColonLoc,
4906 ArrayRef<CXXCtorInitializer*> MemInits,
4908 if (!ConstructorDecl)
4911 AdjustDeclIfTemplate(ConstructorDecl);
4913 CXXConstructorDecl *Constructor
4914 = dyn_cast<CXXConstructorDecl>(ConstructorDecl);
4917 Diag(ColonLoc, diag::err_only_constructors_take_base_inits);
4921 // Mapping for the duplicate initializers check.
4922 // For member initializers, this is keyed with a FieldDecl*.
4923 // For base initializers, this is keyed with a Type*.
4924 llvm::DenseMap<const void *, CXXCtorInitializer *> Members;
4926 // Mapping for the inconsistent anonymous-union initializers check.
4927 RedundantUnionMap MemberUnions;
4929 bool HadError = false;
4930 for (unsigned i = 0; i < MemInits.size(); i++) {
4931 CXXCtorInitializer *Init = MemInits[i];
4933 // Set the source order index.
4934 Init->setSourceOrder(i);
4936 if (Init->isAnyMemberInitializer()) {
4937 const void *Key = GetKeyForMember(Context, Init);
4938 if (CheckRedundantInit(*this, Init, Members[Key]) ||
4939 CheckRedundantUnionInit(*this, Init, MemberUnions))
4941 } else if (Init->isBaseInitializer()) {
4942 const void *Key = GetKeyForMember(Context, Init);
4943 if (CheckRedundantInit(*this, Init, Members[Key]))
4946 assert(Init->isDelegatingInitializer());
4947 // This must be the only initializer
4948 if (MemInits.size() != 1) {
4949 Diag(Init->getSourceLocation(),
4950 diag::err_delegating_initializer_alone)
4951 << Init->getSourceRange() << MemInits[i ? 0 : 1]->getSourceRange();
4952 // We will treat this as being the only initializer.
4954 SetDelegatingInitializer(Constructor, MemInits[i]);
4955 // Return immediately as the initializer is set.
4963 DiagnoseBaseOrMemInitializerOrder(*this, Constructor, MemInits);
4965 SetCtorInitializers(Constructor, AnyErrors, MemInits);
4967 DiagnoseUninitializedFields(*this, Constructor);
4971 Sema::MarkBaseAndMemberDestructorsReferenced(SourceLocation Location,
4972 CXXRecordDecl *ClassDecl) {
4973 // Ignore dependent contexts. Also ignore unions, since their members never
4974 // have destructors implicitly called.
4975 if (ClassDecl->isDependentContext() || ClassDecl->isUnion())
4978 // FIXME: all the access-control diagnostics are positioned on the
4979 // field/base declaration. That's probably good; that said, the
4980 // user might reasonably want to know why the destructor is being
4981 // emitted, and we currently don't say.
4983 // Non-static data members.
4984 for (auto *Field : ClassDecl->fields()) {
4985 if (Field->isInvalidDecl())
4988 // Don't destroy incomplete or zero-length arrays.
4989 if (isIncompleteOrZeroLengthArrayType(Context, Field->getType()))
4992 QualType FieldType = Context.getBaseElementType(Field->getType());
4994 const RecordType* RT = FieldType->getAs<RecordType>();
4998 CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
4999 if (FieldClassDecl->isInvalidDecl())
5001 if (FieldClassDecl->hasIrrelevantDestructor())
5003 // The destructor for an implicit anonymous union member is never invoked.
5004 if (FieldClassDecl->isUnion() && FieldClassDecl->isAnonymousStructOrUnion())
5007 CXXDestructorDecl *Dtor = LookupDestructor(FieldClassDecl);
5008 assert(Dtor && "No dtor found for FieldClassDecl!");
5009 CheckDestructorAccess(Field->getLocation(), Dtor,
5010 PDiag(diag::err_access_dtor_field)
5011 << Field->getDeclName()
5014 MarkFunctionReferenced(Location, Dtor);
5015 DiagnoseUseOfDecl(Dtor, Location);
5018 llvm::SmallPtrSet<const RecordType *, 8> DirectVirtualBases;
5021 for (const auto &Base : ClassDecl->bases()) {
5022 // Bases are always records in a well-formed non-dependent class.
5023 const RecordType *RT = Base.getType()->getAs<RecordType>();
5025 // Remember direct virtual bases.
5026 if (Base.isVirtual())
5027 DirectVirtualBases.insert(RT);
5029 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5030 // If our base class is invalid, we probably can't get its dtor anyway.
5031 if (BaseClassDecl->isInvalidDecl())
5033 if (BaseClassDecl->hasIrrelevantDestructor())
5036 CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
5037 assert(Dtor && "No dtor found for BaseClassDecl!");
5039 // FIXME: caret should be on the start of the class name
5040 CheckDestructorAccess(Base.getLocStart(), Dtor,
5041 PDiag(diag::err_access_dtor_base)
5043 << Base.getSourceRange(),
5044 Context.getTypeDeclType(ClassDecl));
5046 MarkFunctionReferenced(Location, Dtor);
5047 DiagnoseUseOfDecl(Dtor, Location);
5051 for (const auto &VBase : ClassDecl->vbases()) {
5052 // Bases are always records in a well-formed non-dependent class.
5053 const RecordType *RT = VBase.getType()->castAs<RecordType>();
5055 // Ignore direct virtual bases.
5056 if (DirectVirtualBases.count(RT))
5059 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5060 // If our base class is invalid, we probably can't get its dtor anyway.
5061 if (BaseClassDecl->isInvalidDecl())
5063 if (BaseClassDecl->hasIrrelevantDestructor())
5066 CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
5067 assert(Dtor && "No dtor found for BaseClassDecl!");
5068 if (CheckDestructorAccess(
5069 ClassDecl->getLocation(), Dtor,
5070 PDiag(diag::err_access_dtor_vbase)
5071 << Context.getTypeDeclType(ClassDecl) << VBase.getType(),
5072 Context.getTypeDeclType(ClassDecl)) ==
5074 CheckDerivedToBaseConversion(
5075 Context.getTypeDeclType(ClassDecl), VBase.getType(),
5076 diag::err_access_dtor_vbase, 0, ClassDecl->getLocation(),
5077 SourceRange(), DeclarationName(), nullptr);
5080 MarkFunctionReferenced(Location, Dtor);
5081 DiagnoseUseOfDecl(Dtor, Location);
5085 void Sema::ActOnDefaultCtorInitializers(Decl *CDtorDecl) {
5089 if (CXXConstructorDecl *Constructor
5090 = dyn_cast<CXXConstructorDecl>(CDtorDecl)) {
5091 SetCtorInitializers(Constructor, /*AnyErrors=*/false);
5092 DiagnoseUninitializedFields(*this, Constructor);
5096 bool Sema::isAbstractType(SourceLocation Loc, QualType T) {
5097 if (!getLangOpts().CPlusPlus)
5100 const auto *RD = Context.getBaseElementType(T)->getAsCXXRecordDecl();
5104 // FIXME: Per [temp.inst]p1, we are supposed to trigger instantiation of a
5105 // class template specialization here, but doing so breaks a lot of code.
5107 // We can't answer whether something is abstract until it has a
5108 // definition. If it's currently being defined, we'll walk back
5109 // over all the declarations when we have a full definition.
5110 const CXXRecordDecl *Def = RD->getDefinition();
5111 if (!Def || Def->isBeingDefined())
5114 return RD->isAbstract();
5117 bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T,
5118 TypeDiagnoser &Diagnoser) {
5119 if (!isAbstractType(Loc, T))
5122 T = Context.getBaseElementType(T);
5123 Diagnoser.diagnose(*this, Loc, T);
5124 DiagnoseAbstractType(T->getAsCXXRecordDecl());
5128 void Sema::DiagnoseAbstractType(const CXXRecordDecl *RD) {
5129 // Check if we've already emitted the list of pure virtual functions
5131 if (PureVirtualClassDiagSet && PureVirtualClassDiagSet->count(RD))
5134 // If the diagnostic is suppressed, don't emit the notes. We're only
5135 // going to emit them once, so try to attach them to a diagnostic we're
5136 // actually going to show.
5137 if (Diags.isLastDiagnosticIgnored())
5140 CXXFinalOverriderMap FinalOverriders;
5141 RD->getFinalOverriders(FinalOverriders);
5143 // Keep a set of seen pure methods so we won't diagnose the same method
5145 llvm::SmallPtrSet<const CXXMethodDecl *, 8> SeenPureMethods;
5147 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
5148 MEnd = FinalOverriders.end();
5151 for (OverridingMethods::iterator SO = M->second.begin(),
5152 SOEnd = M->second.end();
5153 SO != SOEnd; ++SO) {
5154 // C++ [class.abstract]p4:
5155 // A class is abstract if it contains or inherits at least one
5156 // pure virtual function for which the final overrider is pure
5160 if (SO->second.size() != 1)
5163 if (!SO->second.front().Method->isPure())
5166 if (!SeenPureMethods.insert(SO->second.front().Method).second)
5169 Diag(SO->second.front().Method->getLocation(),
5170 diag::note_pure_virtual_function)
5171 << SO->second.front().Method->getDeclName() << RD->getDeclName();
5175 if (!PureVirtualClassDiagSet)
5176 PureVirtualClassDiagSet.reset(new RecordDeclSetTy);
5177 PureVirtualClassDiagSet->insert(RD);
5181 struct AbstractUsageInfo {
5183 CXXRecordDecl *Record;
5184 CanQualType AbstractType;
5187 AbstractUsageInfo(Sema &S, CXXRecordDecl *Record)
5188 : S(S), Record(Record),
5189 AbstractType(S.Context.getCanonicalType(
5190 S.Context.getTypeDeclType(Record))),
5193 void DiagnoseAbstractType() {
5194 if (Invalid) return;
5195 S.DiagnoseAbstractType(Record);
5199 void CheckType(const NamedDecl *D, TypeLoc TL, Sema::AbstractDiagSelID Sel);
5202 struct CheckAbstractUsage {
5203 AbstractUsageInfo &Info;
5204 const NamedDecl *Ctx;
5206 CheckAbstractUsage(AbstractUsageInfo &Info, const NamedDecl *Ctx)
5207 : Info(Info), Ctx(Ctx) {}
5209 void Visit(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
5210 switch (TL.getTypeLocClass()) {
5211 #define ABSTRACT_TYPELOC(CLASS, PARENT)
5212 #define TYPELOC(CLASS, PARENT) \
5213 case TypeLoc::CLASS: Check(TL.castAs<CLASS##TypeLoc>(), Sel); break;
5214 #include "clang/AST/TypeLocNodes.def"
5218 void Check(FunctionProtoTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5219 Visit(TL.getReturnLoc(), Sema::AbstractReturnType);
5220 for (unsigned I = 0, E = TL.getNumParams(); I != E; ++I) {
5221 if (!TL.getParam(I))
5224 TypeSourceInfo *TSI = TL.getParam(I)->getTypeSourceInfo();
5225 if (TSI) Visit(TSI->getTypeLoc(), Sema::AbstractParamType);
5229 void Check(ArrayTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5230 Visit(TL.getElementLoc(), Sema::AbstractArrayType);
5233 void Check(TemplateSpecializationTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5234 // Visit the type parameters from a permissive context.
5235 for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) {
5236 TemplateArgumentLoc TAL = TL.getArgLoc(I);
5237 if (TAL.getArgument().getKind() == TemplateArgument::Type)
5238 if (TypeSourceInfo *TSI = TAL.getTypeSourceInfo())
5239 Visit(TSI->getTypeLoc(), Sema::AbstractNone);
5240 // TODO: other template argument types?
5244 // Visit pointee types from a permissive context.
5245 #define CheckPolymorphic(Type) \
5246 void Check(Type TL, Sema::AbstractDiagSelID Sel) { \
5247 Visit(TL.getNextTypeLoc(), Sema::AbstractNone); \
5249 CheckPolymorphic(PointerTypeLoc)
5250 CheckPolymorphic(ReferenceTypeLoc)
5251 CheckPolymorphic(MemberPointerTypeLoc)
5252 CheckPolymorphic(BlockPointerTypeLoc)
5253 CheckPolymorphic(AtomicTypeLoc)
5255 /// Handle all the types we haven't given a more specific
5256 /// implementation for above.
5257 void Check(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
5258 // Every other kind of type that we haven't called out already
5259 // that has an inner type is either (1) sugar or (2) contains that
5260 // inner type in some way as a subobject.
5261 if (TypeLoc Next = TL.getNextTypeLoc())
5262 return Visit(Next, Sel);
5264 // If there's no inner type and we're in a permissive context,
5266 if (Sel == Sema::AbstractNone) return;
5268 // Check whether the type matches the abstract type.
5269 QualType T = TL.getType();
5270 if (T->isArrayType()) {
5271 Sel = Sema::AbstractArrayType;
5272 T = Info.S.Context.getBaseElementType(T);
5274 CanQualType CT = T->getCanonicalTypeUnqualified().getUnqualifiedType();
5275 if (CT != Info.AbstractType) return;
5277 // It matched; do some magic.
5278 if (Sel == Sema::AbstractArrayType) {
5279 Info.S.Diag(Ctx->getLocation(), diag::err_array_of_abstract_type)
5280 << T << TL.getSourceRange();
5282 Info.S.Diag(Ctx->getLocation(), diag::err_abstract_type_in_decl)
5283 << Sel << T << TL.getSourceRange();
5285 Info.DiagnoseAbstractType();
5289 void AbstractUsageInfo::CheckType(const NamedDecl *D, TypeLoc TL,
5290 Sema::AbstractDiagSelID Sel) {
5291 CheckAbstractUsage(*this, D).Visit(TL, Sel);
5296 /// Check for invalid uses of an abstract type in a method declaration.
5297 static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
5298 CXXMethodDecl *MD) {
5299 // No need to do the check on definitions, which require that
5300 // the return/param types be complete.
5301 if (MD->doesThisDeclarationHaveABody())
5304 // For safety's sake, just ignore it if we don't have type source
5305 // information. This should never happen for non-implicit methods,
5307 if (TypeSourceInfo *TSI = MD->getTypeSourceInfo())
5308 Info.CheckType(MD, TSI->getTypeLoc(), Sema::AbstractNone);
5311 /// Check for invalid uses of an abstract type within a class definition.
5312 static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
5313 CXXRecordDecl *RD) {
5314 for (auto *D : RD->decls()) {
5315 if (D->isImplicit()) continue;
5317 // Methods and method templates.
5318 if (isa<CXXMethodDecl>(D)) {
5319 CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(D));
5320 } else if (isa<FunctionTemplateDecl>(D)) {
5321 FunctionDecl *FD = cast<FunctionTemplateDecl>(D)->getTemplatedDecl();
5322 CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(FD));
5324 // Fields and static variables.
5325 } else if (isa<FieldDecl>(D)) {
5326 FieldDecl *FD = cast<FieldDecl>(D);
5327 if (TypeSourceInfo *TSI = FD->getTypeSourceInfo())
5328 Info.CheckType(FD, TSI->getTypeLoc(), Sema::AbstractFieldType);
5329 } else if (isa<VarDecl>(D)) {
5330 VarDecl *VD = cast<VarDecl>(D);
5331 if (TypeSourceInfo *TSI = VD->getTypeSourceInfo())
5332 Info.CheckType(VD, TSI->getTypeLoc(), Sema::AbstractVariableType);
5334 // Nested classes and class templates.
5335 } else if (isa<CXXRecordDecl>(D)) {
5336 CheckAbstractClassUsage(Info, cast<CXXRecordDecl>(D));
5337 } else if (isa<ClassTemplateDecl>(D)) {
5338 CheckAbstractClassUsage(Info,
5339 cast<ClassTemplateDecl>(D)->getTemplatedDecl());
5344 static void ReferenceDllExportedMethods(Sema &S, CXXRecordDecl *Class) {
5345 Attr *ClassAttr = getDLLAttr(Class);
5349 assert(ClassAttr->getKind() == attr::DLLExport);
5351 TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
5353 if (TSK == TSK_ExplicitInstantiationDeclaration)
5354 // Don't go any further if this is just an explicit instantiation
5358 for (Decl *Member : Class->decls()) {
5359 auto *MD = dyn_cast<CXXMethodDecl>(Member);
5363 if (Member->getAttr<DLLExportAttr>()) {
5364 if (MD->isUserProvided()) {
5365 // Instantiate non-default class member functions ...
5367 // .. except for certain kinds of template specializations.
5368 if (TSK == TSK_ImplicitInstantiation && !ClassAttr->isInherited())
5371 S.MarkFunctionReferenced(Class->getLocation(), MD);
5373 // The function will be passed to the consumer when its definition is
5375 } else if (!MD->isTrivial() || MD->isExplicitlyDefaulted() ||
5376 MD->isCopyAssignmentOperator() ||
5377 MD->isMoveAssignmentOperator()) {
5378 // Synthesize and instantiate non-trivial implicit methods, explicitly
5379 // defaulted methods, and the copy and move assignment operators. The
5380 // latter are exported even if they are trivial, because the address of
5381 // an operator can be taken and should compare equal accross libraries.
5382 DiagnosticErrorTrap Trap(S.Diags);
5383 S.MarkFunctionReferenced(Class->getLocation(), MD);
5384 if (Trap.hasErrorOccurred()) {
5385 S.Diag(ClassAttr->getLocation(), diag::note_due_to_dllexported_class)
5386 << Class->getName() << !S.getLangOpts().CPlusPlus11;
5390 // There is no later point when we will see the definition of this
5391 // function, so pass it to the consumer now.
5392 S.Consumer.HandleTopLevelDecl(DeclGroupRef(MD));
5398 static void checkForMultipleExportedDefaultConstructors(Sema &S,
5399 CXXRecordDecl *Class) {
5400 // Only the MS ABI has default constructor closures, so we don't need to do
5401 // this semantic checking anywhere else.
5402 if (!S.Context.getTargetInfo().getCXXABI().isMicrosoft())
5405 CXXConstructorDecl *LastExportedDefaultCtor = nullptr;
5406 for (Decl *Member : Class->decls()) {
5407 // Look for exported default constructors.
5408 auto *CD = dyn_cast<CXXConstructorDecl>(Member);
5409 if (!CD || !CD->isDefaultConstructor())
5411 auto *Attr = CD->getAttr<DLLExportAttr>();
5415 // If the class is non-dependent, mark the default arguments as ODR-used so
5416 // that we can properly codegen the constructor closure.
5417 if (!Class->isDependentContext()) {
5418 for (ParmVarDecl *PD : CD->parameters()) {
5419 (void)S.CheckCXXDefaultArgExpr(Attr->getLocation(), CD, PD);
5420 S.DiscardCleanupsInEvaluationContext();
5424 if (LastExportedDefaultCtor) {
5425 S.Diag(LastExportedDefaultCtor->getLocation(),
5426 diag::err_attribute_dll_ambiguous_default_ctor)
5428 S.Diag(CD->getLocation(), diag::note_entity_declared_at)
5429 << CD->getDeclName();
5432 LastExportedDefaultCtor = CD;
5436 /// \brief Check class-level dllimport/dllexport attribute.
5437 void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
5438 Attr *ClassAttr = getDLLAttr(Class);
5440 // MSVC inherits DLL attributes to partial class template specializations.
5441 if (Context.getTargetInfo().getCXXABI().isMicrosoft() && !ClassAttr) {
5442 if (auto *Spec = dyn_cast<ClassTemplatePartialSpecializationDecl>(Class)) {
5443 if (Attr *TemplateAttr =
5444 getDLLAttr(Spec->getSpecializedTemplate()->getTemplatedDecl())) {
5445 auto *A = cast<InheritableAttr>(TemplateAttr->clone(getASTContext()));
5446 A->setInherited(true);
5455 if (!Class->isExternallyVisible()) {
5456 Diag(Class->getLocation(), diag::err_attribute_dll_not_extern)
5457 << Class << ClassAttr;
5461 if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
5462 !ClassAttr->isInherited()) {
5463 // Diagnose dll attributes on members of class with dll attribute.
5464 for (Decl *Member : Class->decls()) {
5465 if (!isa<VarDecl>(Member) && !isa<CXXMethodDecl>(Member))
5467 InheritableAttr *MemberAttr = getDLLAttr(Member);
5468 if (!MemberAttr || MemberAttr->isInherited() || Member->isInvalidDecl())
5471 Diag(MemberAttr->getLocation(),
5472 diag::err_attribute_dll_member_of_dll_class)
5473 << MemberAttr << ClassAttr;
5474 Diag(ClassAttr->getLocation(), diag::note_previous_attribute);
5475 Member->setInvalidDecl();
5479 if (Class->getDescribedClassTemplate())
5480 // Don't inherit dll attribute until the template is instantiated.
5483 // The class is either imported or exported.
5484 const bool ClassExported = ClassAttr->getKind() == attr::DLLExport;
5486 TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
5488 // Ignore explicit dllexport on explicit class template instantiation declarations.
5489 if (ClassExported && !ClassAttr->isInherited() &&
5490 TSK == TSK_ExplicitInstantiationDeclaration) {
5491 Class->dropAttr<DLLExportAttr>();
5495 // Force declaration of implicit members so they can inherit the attribute.
5496 ForceDeclarationOfImplicitMembers(Class);
5498 // FIXME: MSVC's docs say all bases must be exportable, but this doesn't
5499 // seem to be true in practice?
5501 for (Decl *Member : Class->decls()) {
5502 VarDecl *VD = dyn_cast<VarDecl>(Member);
5503 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Member);
5505 // Only methods and static fields inherit the attributes.
5510 // Don't process deleted methods.
5511 if (MD->isDeleted())
5514 if (MD->isInlined()) {
5515 // MinGW does not import or export inline methods.
5516 if (!Context.getTargetInfo().getCXXABI().isMicrosoft() &&
5517 !Context.getTargetInfo().getTriple().isWindowsItaniumEnvironment())
5520 // MSVC versions before 2015 don't export the move assignment operators
5521 // and move constructor, so don't attempt to import/export them if
5522 // we have a definition.
5523 auto *Ctor = dyn_cast<CXXConstructorDecl>(MD);
5524 if ((MD->isMoveAssignmentOperator() ||
5525 (Ctor && Ctor->isMoveConstructor())) &&
5526 !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015))
5529 // MSVC2015 doesn't export trivial defaulted x-tor but copy assign
5530 // operator is exported anyway.
5531 if (getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015) &&
5532 (Ctor || isa<CXXDestructorDecl>(MD)) && MD->isTrivial())
5537 if (!cast<NamedDecl>(Member)->isExternallyVisible())
5540 if (!getDLLAttr(Member)) {
5542 cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
5543 NewAttr->setInherited(true);
5544 Member->addAttr(NewAttr);
5549 DelayedDllExportClasses.push_back(Class);
5552 /// \brief Perform propagation of DLL attributes from a derived class to a
5553 /// templated base class for MS compatibility.
5554 void Sema::propagateDLLAttrToBaseClassTemplate(
5555 CXXRecordDecl *Class, Attr *ClassAttr,
5556 ClassTemplateSpecializationDecl *BaseTemplateSpec, SourceLocation BaseLoc) {
5558 BaseTemplateSpec->getSpecializedTemplate()->getTemplatedDecl())) {
5559 // If the base class template has a DLL attribute, don't try to change it.
5563 auto TSK = BaseTemplateSpec->getSpecializationKind();
5564 if (!getDLLAttr(BaseTemplateSpec) &&
5565 (TSK == TSK_Undeclared || TSK == TSK_ExplicitInstantiationDeclaration ||
5566 TSK == TSK_ImplicitInstantiation)) {
5567 // The template hasn't been instantiated yet (or it has, but only as an
5568 // explicit instantiation declaration or implicit instantiation, which means
5569 // we haven't codegenned any members yet), so propagate the attribute.
5570 auto *NewAttr = cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
5571 NewAttr->setInherited(true);
5572 BaseTemplateSpec->addAttr(NewAttr);
5574 // If the template is already instantiated, checkDLLAttributeRedeclaration()
5575 // needs to be run again to work see the new attribute. Otherwise this will
5576 // get run whenever the template is instantiated.
5577 if (TSK != TSK_Undeclared)
5578 checkClassLevelDLLAttribute(BaseTemplateSpec);
5583 if (getDLLAttr(BaseTemplateSpec)) {
5584 // The template has already been specialized or instantiated with an
5585 // attribute, explicitly or through propagation. We should not try to change
5590 // The template was previously instantiated or explicitly specialized without
5591 // a dll attribute, It's too late for us to add an attribute, so warn that
5592 // this is unsupported.
5593 Diag(BaseLoc, diag::warn_attribute_dll_instantiated_base_class)
5594 << BaseTemplateSpec->isExplicitSpecialization();
5595 Diag(ClassAttr->getLocation(), diag::note_attribute);
5596 if (BaseTemplateSpec->isExplicitSpecialization()) {
5597 Diag(BaseTemplateSpec->getLocation(),
5598 diag::note_template_class_explicit_specialization_was_here)
5599 << BaseTemplateSpec;
5601 Diag(BaseTemplateSpec->getPointOfInstantiation(),
5602 diag::note_template_class_instantiation_was_here)
5603 << BaseTemplateSpec;
5607 static void DefineImplicitSpecialMember(Sema &S, CXXMethodDecl *MD,
5608 SourceLocation DefaultLoc) {
5609 switch (S.getSpecialMember(MD)) {
5610 case Sema::CXXDefaultConstructor:
5611 S.DefineImplicitDefaultConstructor(DefaultLoc,
5612 cast<CXXConstructorDecl>(MD));
5614 case Sema::CXXCopyConstructor:
5615 S.DefineImplicitCopyConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
5617 case Sema::CXXCopyAssignment:
5618 S.DefineImplicitCopyAssignment(DefaultLoc, MD);
5620 case Sema::CXXDestructor:
5621 S.DefineImplicitDestructor(DefaultLoc, cast<CXXDestructorDecl>(MD));
5623 case Sema::CXXMoveConstructor:
5624 S.DefineImplicitMoveConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
5626 case Sema::CXXMoveAssignment:
5627 S.DefineImplicitMoveAssignment(DefaultLoc, MD);
5629 case Sema::CXXInvalid:
5630 llvm_unreachable("Invalid special member.");
5634 /// \brief Perform semantic checks on a class definition that has been
5635 /// completing, introducing implicitly-declared members, checking for
5636 /// abstract types, etc.
5637 void Sema::CheckCompletedCXXClass(CXXRecordDecl *Record) {
5641 if (Record->isAbstract() && !Record->isInvalidDecl()) {
5642 AbstractUsageInfo Info(*this, Record);
5643 CheckAbstractClassUsage(Info, Record);
5646 // If this is not an aggregate type and has no user-declared constructor,
5647 // complain about any non-static data members of reference or const scalar
5648 // type, since they will never get initializers.
5649 if (!Record->isInvalidDecl() && !Record->isDependentType() &&
5650 !Record->isAggregate() && !Record->hasUserDeclaredConstructor() &&
5651 !Record->isLambda()) {
5652 bool Complained = false;
5653 for (const auto *F : Record->fields()) {
5654 if (F->hasInClassInitializer() || F->isUnnamedBitfield())
5657 if (F->getType()->isReferenceType() ||
5658 (F->getType().isConstQualified() && F->getType()->isScalarType())) {
5660 Diag(Record->getLocation(), diag::warn_no_constructor_for_refconst)
5661 << Record->getTagKind() << Record;
5665 Diag(F->getLocation(), diag::note_refconst_member_not_initialized)
5666 << F->getType()->isReferenceType()
5667 << F->getDeclName();
5672 if (Record->getIdentifier()) {
5673 // C++ [class.mem]p13:
5674 // If T is the name of a class, then each of the following shall have a
5675 // name different from T:
5676 // - every member of every anonymous union that is a member of class T.
5678 // C++ [class.mem]p14:
5679 // In addition, if class T has a user-declared constructor (12.1), every
5680 // non-static data member of class T shall have a name different from T.
5681 DeclContext::lookup_result R = Record->lookup(Record->getDeclName());
5682 for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E;
5685 if ((isa<FieldDecl>(D) && Record->hasUserDeclaredConstructor()) ||
5686 isa<IndirectFieldDecl>(D)) {
5687 Diag(D->getLocation(), diag::err_member_name_of_class)
5688 << D->getDeclName();
5694 // Warn if the class has virtual methods but non-virtual public destructor.
5695 if (Record->isPolymorphic() && !Record->isDependentType()) {
5696 CXXDestructorDecl *dtor = Record->getDestructor();
5697 if ((!dtor || (!dtor->isVirtual() && dtor->getAccess() == AS_public)) &&
5698 !Record->hasAttr<FinalAttr>())
5699 Diag(dtor ? dtor->getLocation() : Record->getLocation(),
5700 diag::warn_non_virtual_dtor) << Context.getRecordType(Record);
5703 if (Record->isAbstract()) {
5704 if (FinalAttr *FA = Record->getAttr<FinalAttr>()) {
5705 Diag(Record->getLocation(), diag::warn_abstract_final_class)
5706 << FA->isSpelledAsSealed();
5707 DiagnoseAbstractType(Record);
5711 bool HasMethodWithOverrideControl = false,
5712 HasOverridingMethodWithoutOverrideControl = false;
5713 if (!Record->isDependentType()) {
5714 for (auto *M : Record->methods()) {
5715 // See if a method overloads virtual methods in a base
5716 // class without overriding any.
5718 DiagnoseHiddenVirtualMethods(M);
5719 if (M->hasAttr<OverrideAttr>())
5720 HasMethodWithOverrideControl = true;
5721 else if (M->size_overridden_methods() > 0)
5722 HasOverridingMethodWithoutOverrideControl = true;
5723 // Check whether the explicitly-defaulted special members are valid.
5724 if (!M->isInvalidDecl() && M->isExplicitlyDefaulted())
5725 CheckExplicitlyDefaultedSpecialMember(M);
5727 // For an explicitly defaulted or deleted special member, we defer
5728 // determining triviality until the class is complete. That time is now!
5729 CXXSpecialMember CSM = getSpecialMember(M);
5730 if (!M->isImplicit() && !M->isUserProvided()) {
5731 if (CSM != CXXInvalid) {
5732 M->setTrivial(SpecialMemberIsTrivial(M, CSM));
5734 // Inform the class that we've finished declaring this member.
5735 Record->finishedDefaultedOrDeletedMember(M);
5739 if (!M->isInvalidDecl() && M->isExplicitlyDefaulted() &&
5740 M->hasAttr<DLLExportAttr>()) {
5741 if (getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015) &&
5743 (CSM == CXXDefaultConstructor || CSM == CXXCopyConstructor ||
5744 CSM == CXXDestructor))
5745 M->dropAttr<DLLExportAttr>();
5747 if (M->hasAttr<DLLExportAttr>()) {
5748 DefineImplicitSpecialMember(*this, M, M->getLocation());
5749 ActOnFinishInlineFunctionDef(M);
5755 if (HasMethodWithOverrideControl &&
5756 HasOverridingMethodWithoutOverrideControl) {
5757 // At least one method has the 'override' control declared.
5758 // Diagnose all other overridden methods which do not have 'override' specified on them.
5759 for (auto *M : Record->methods())
5760 DiagnoseAbsenceOfOverrideControl(M);
5763 // ms_struct is a request to use the same ABI rules as MSVC. Check
5764 // whether this class uses any C++ features that are implemented
5765 // completely differently in MSVC, and if so, emit a diagnostic.
5766 // That diagnostic defaults to an error, but we allow projects to
5767 // map it down to a warning (or ignore it). It's a fairly common
5768 // practice among users of the ms_struct pragma to mass-annotate
5769 // headers, sweeping up a bunch of types that the project doesn't
5770 // really rely on MSVC-compatible layout for. We must therefore
5771 // support "ms_struct except for C++ stuff" as a secondary ABI.
5772 if (Record->isMsStruct(Context) &&
5773 (Record->isPolymorphic() || Record->getNumBases())) {
5774 Diag(Record->getLocation(), diag::warn_cxx_ms_struct);
5777 checkClassLevelDLLAttribute(Record);
5780 /// Look up the special member function that would be called by a special
5781 /// member function for a subobject of class type.
5783 /// \param Class The class type of the subobject.
5784 /// \param CSM The kind of special member function.
5785 /// \param FieldQuals If the subobject is a field, its cv-qualifiers.
5786 /// \param ConstRHS True if this is a copy operation with a const object
5787 /// on its RHS, that is, if the argument to the outer special member
5788 /// function is 'const' and this is not a field marked 'mutable'.
5789 static Sema::SpecialMemberOverloadResult *lookupCallFromSpecialMember(
5790 Sema &S, CXXRecordDecl *Class, Sema::CXXSpecialMember CSM,
5791 unsigned FieldQuals, bool ConstRHS) {
5792 unsigned LHSQuals = 0;
5793 if (CSM == Sema::CXXCopyAssignment || CSM == Sema::CXXMoveAssignment)
5794 LHSQuals = FieldQuals;
5796 unsigned RHSQuals = FieldQuals;
5797 if (CSM == Sema::CXXDefaultConstructor || CSM == Sema::CXXDestructor)
5800 RHSQuals |= Qualifiers::Const;
5802 return S.LookupSpecialMember(Class, CSM,
5803 RHSQuals & Qualifiers::Const,
5804 RHSQuals & Qualifiers::Volatile,
5806 LHSQuals & Qualifiers::Const,
5807 LHSQuals & Qualifiers::Volatile);
5810 class Sema::InheritedConstructorInfo {
5812 SourceLocation UseLoc;
5814 /// A mapping from the base classes through which the constructor was
5815 /// inherited to the using shadow declaration in that base class (or a null
5816 /// pointer if the constructor was declared in that base class).
5817 llvm::DenseMap<CXXRecordDecl *, ConstructorUsingShadowDecl *>
5821 InheritedConstructorInfo(Sema &S, SourceLocation UseLoc,
5822 ConstructorUsingShadowDecl *Shadow)
5823 : S(S), UseLoc(UseLoc) {
5824 bool DiagnosedMultipleConstructedBases = false;
5825 CXXRecordDecl *ConstructedBase = nullptr;
5826 UsingDecl *ConstructedBaseUsing = nullptr;
5828 // Find the set of such base class subobjects and check that there's a
5829 // unique constructed subobject.
5830 for (auto *D : Shadow->redecls()) {
5831 auto *DShadow = cast<ConstructorUsingShadowDecl>(D);
5832 auto *DNominatedBase = DShadow->getNominatedBaseClass();
5833 auto *DConstructedBase = DShadow->getConstructedBaseClass();
5835 InheritedFromBases.insert(
5836 std::make_pair(DNominatedBase->getCanonicalDecl(),
5837 DShadow->getNominatedBaseClassShadowDecl()));
5838 if (DShadow->constructsVirtualBase())
5839 InheritedFromBases.insert(
5840 std::make_pair(DConstructedBase->getCanonicalDecl(),
5841 DShadow->getConstructedBaseClassShadowDecl()));
5843 assert(DNominatedBase == DConstructedBase);
5845 // [class.inhctor.init]p2:
5846 // If the constructor was inherited from multiple base class subobjects
5847 // of type B, the program is ill-formed.
5848 if (!ConstructedBase) {
5849 ConstructedBase = DConstructedBase;
5850 ConstructedBaseUsing = D->getUsingDecl();
5851 } else if (ConstructedBase != DConstructedBase &&
5852 !Shadow->isInvalidDecl()) {
5853 if (!DiagnosedMultipleConstructedBases) {
5854 S.Diag(UseLoc, diag::err_ambiguous_inherited_constructor)
5855 << Shadow->getTargetDecl();
5856 S.Diag(ConstructedBaseUsing->getLocation(),
5857 diag::note_ambiguous_inherited_constructor_using)
5859 DiagnosedMultipleConstructedBases = true;
5861 S.Diag(D->getUsingDecl()->getLocation(),
5862 diag::note_ambiguous_inherited_constructor_using)
5863 << DConstructedBase;
5867 if (DiagnosedMultipleConstructedBases)
5868 Shadow->setInvalidDecl();
5871 /// Find the constructor to use for inherited construction of a base class,
5872 /// and whether that base class constructor inherits the constructor from a
5873 /// virtual base class (in which case it won't actually invoke it).
5874 std::pair<CXXConstructorDecl *, bool>
5875 findConstructorForBase(CXXRecordDecl *Base, CXXConstructorDecl *Ctor) const {
5876 auto It = InheritedFromBases.find(Base->getCanonicalDecl());
5877 if (It == InheritedFromBases.end())
5878 return std::make_pair(nullptr, false);
5880 // This is an intermediary class.
5882 return std::make_pair(
5883 S.findInheritingConstructor(UseLoc, Ctor, It->second),
5884 It->second->constructsVirtualBase());
5886 // This is the base class from which the constructor was inherited.
5887 return std::make_pair(Ctor, false);
5891 /// Is the special member function which would be selected to perform the
5892 /// specified operation on the specified class type a constexpr constructor?
5894 specialMemberIsConstexpr(Sema &S, CXXRecordDecl *ClassDecl,
5895 Sema::CXXSpecialMember CSM, unsigned Quals,
5897 CXXConstructorDecl *InheritedCtor = nullptr,
5898 Sema::InheritedConstructorInfo *Inherited = nullptr) {
5899 // If we're inheriting a constructor, see if we need to call it for this base
5901 if (InheritedCtor) {
5902 assert(CSM == Sema::CXXDefaultConstructor);
5904 Inherited->findConstructorForBase(ClassDecl, InheritedCtor).first;
5906 return BaseCtor->isConstexpr();
5909 if (CSM == Sema::CXXDefaultConstructor)
5910 return ClassDecl->hasConstexprDefaultConstructor();
5912 Sema::SpecialMemberOverloadResult *SMOR =
5913 lookupCallFromSpecialMember(S, ClassDecl, CSM, Quals, ConstRHS);
5914 if (!SMOR || !SMOR->getMethod())
5915 // A constructor we wouldn't select can't be "involved in initializing"
5918 return SMOR->getMethod()->isConstexpr();
5921 /// Determine whether the specified special member function would be constexpr
5922 /// if it were implicitly defined.
5923 static bool defaultedSpecialMemberIsConstexpr(
5924 Sema &S, CXXRecordDecl *ClassDecl, Sema::CXXSpecialMember CSM,
5925 bool ConstArg, CXXConstructorDecl *InheritedCtor = nullptr,
5926 Sema::InheritedConstructorInfo *Inherited = nullptr) {
5927 if (!S.getLangOpts().CPlusPlus11)
5930 // C++11 [dcl.constexpr]p4:
5931 // In the definition of a constexpr constructor [...]
5934 case Sema::CXXDefaultConstructor:
5937 // Since default constructor lookup is essentially trivial (and cannot
5938 // involve, for instance, template instantiation), we compute whether a
5939 // defaulted default constructor is constexpr directly within CXXRecordDecl.
5941 // This is important for performance; we need to know whether the default
5942 // constructor is constexpr to determine whether the type is a literal type.
5943 return ClassDecl->defaultedDefaultConstructorIsConstexpr();
5945 case Sema::CXXCopyConstructor:
5946 case Sema::CXXMoveConstructor:
5947 // For copy or move constructors, we need to perform overload resolution.
5950 case Sema::CXXCopyAssignment:
5951 case Sema::CXXMoveAssignment:
5952 if (!S.getLangOpts().CPlusPlus14)
5954 // In C++1y, we need to perform overload resolution.
5958 case Sema::CXXDestructor:
5959 case Sema::CXXInvalid:
5963 // -- if the class is a non-empty union, or for each non-empty anonymous
5964 // union member of a non-union class, exactly one non-static data member
5965 // shall be initialized; [DR1359]
5967 // If we squint, this is guaranteed, since exactly one non-static data member
5968 // will be initialized (if the constructor isn't deleted), we just don't know
5970 if (Ctor && ClassDecl->isUnion())
5971 return CSM == Sema::CXXDefaultConstructor
5972 ? ClassDecl->hasInClassInitializer() ||
5973 !ClassDecl->hasVariantMembers()
5976 // -- the class shall not have any virtual base classes;
5977 if (Ctor && ClassDecl->getNumVBases())
5980 // C++1y [class.copy]p26:
5981 // -- [the class] is a literal type, and
5982 if (!Ctor && !ClassDecl->isLiteral())
5985 // -- every constructor involved in initializing [...] base class
5986 // sub-objects shall be a constexpr constructor;
5987 // -- the assignment operator selected to copy/move each direct base
5988 // class is a constexpr function, and
5989 for (const auto &B : ClassDecl->bases()) {
5990 const RecordType *BaseType = B.getType()->getAs<RecordType>();
5991 if (!BaseType) continue;
5993 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
5994 if (!specialMemberIsConstexpr(S, BaseClassDecl, CSM, 0, ConstArg,
5995 InheritedCtor, Inherited))
5999 // -- every constructor involved in initializing non-static data members
6000 // [...] shall be a constexpr constructor;
6001 // -- every non-static data member and base class sub-object shall be
6003 // -- for each non-static data member of X that is of class type (or array
6004 // thereof), the assignment operator selected to copy/move that member is
6005 // a constexpr function
6006 for (const auto *F : ClassDecl->fields()) {
6007 if (F->isInvalidDecl())
6009 if (CSM == Sema::CXXDefaultConstructor && F->hasInClassInitializer())
6011 QualType BaseType = S.Context.getBaseElementType(F->getType());
6012 if (const RecordType *RecordTy = BaseType->getAs<RecordType>()) {
6013 CXXRecordDecl *FieldRecDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
6014 if (!specialMemberIsConstexpr(S, FieldRecDecl, CSM,
6015 BaseType.getCVRQualifiers(),
6016 ConstArg && !F->isMutable()))
6018 } else if (CSM == Sema::CXXDefaultConstructor) {
6023 // All OK, it's constexpr!
6027 static Sema::ImplicitExceptionSpecification
6028 computeImplicitExceptionSpec(Sema &S, SourceLocation Loc, CXXMethodDecl *MD) {
6029 switch (S.getSpecialMember(MD)) {
6030 case Sema::CXXDefaultConstructor:
6031 return S.ComputeDefaultedDefaultCtorExceptionSpec(Loc, MD);
6032 case Sema::CXXCopyConstructor:
6033 return S.ComputeDefaultedCopyCtorExceptionSpec(MD);
6034 case Sema::CXXCopyAssignment:
6035 return S.ComputeDefaultedCopyAssignmentExceptionSpec(MD);
6036 case Sema::CXXMoveConstructor:
6037 return S.ComputeDefaultedMoveCtorExceptionSpec(MD);
6038 case Sema::CXXMoveAssignment:
6039 return S.ComputeDefaultedMoveAssignmentExceptionSpec(MD);
6040 case Sema::CXXDestructor:
6041 return S.ComputeDefaultedDtorExceptionSpec(MD);
6042 case Sema::CXXInvalid:
6045 assert(cast<CXXConstructorDecl>(MD)->getInheritedConstructor() &&
6046 "only special members have implicit exception specs");
6047 return S.ComputeInheritingCtorExceptionSpec(Loc,
6048 cast<CXXConstructorDecl>(MD));
6051 static FunctionProtoType::ExtProtoInfo getImplicitMethodEPI(Sema &S,
6052 CXXMethodDecl *MD) {
6053 FunctionProtoType::ExtProtoInfo EPI;
6055 // Build an exception specification pointing back at this member.
6056 EPI.ExceptionSpec.Type = EST_Unevaluated;
6057 EPI.ExceptionSpec.SourceDecl = MD;
6059 // Set the calling convention to the default for C++ instance methods.
6060 EPI.ExtInfo = EPI.ExtInfo.withCallingConv(
6061 S.Context.getDefaultCallingConvention(/*IsVariadic=*/false,
6062 /*IsCXXMethod=*/true));
6066 void Sema::EvaluateImplicitExceptionSpec(SourceLocation Loc, CXXMethodDecl *MD) {
6067 const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
6068 if (FPT->getExceptionSpecType() != EST_Unevaluated)
6071 // Evaluate the exception specification.
6072 auto IES = computeImplicitExceptionSpec(*this, Loc, MD);
6073 auto ESI = IES.getExceptionSpec();
6075 // Update the type of the special member to use it.
6076 UpdateExceptionSpec(MD, ESI);
6078 // A user-provided destructor can be defined outside the class. When that
6079 // happens, be sure to update the exception specification on both
6081 const FunctionProtoType *CanonicalFPT =
6082 MD->getCanonicalDecl()->getType()->castAs<FunctionProtoType>();
6083 if (CanonicalFPT->getExceptionSpecType() == EST_Unevaluated)
6084 UpdateExceptionSpec(MD->getCanonicalDecl(), ESI);
6087 void Sema::CheckExplicitlyDefaultedSpecialMember(CXXMethodDecl *MD) {
6088 CXXRecordDecl *RD = MD->getParent();
6089 CXXSpecialMember CSM = getSpecialMember(MD);
6091 assert(MD->isExplicitlyDefaulted() && CSM != CXXInvalid &&
6092 "not an explicitly-defaulted special member");
6094 // Whether this was the first-declared instance of the constructor.
6095 // This affects whether we implicitly add an exception spec and constexpr.
6096 bool First = MD == MD->getCanonicalDecl();
6098 bool HadError = false;
6100 // C++11 [dcl.fct.def.default]p1:
6101 // A function that is explicitly defaulted shall
6102 // -- be a special member function (checked elsewhere),
6103 // -- have the same type (except for ref-qualifiers, and except that a
6104 // copy operation can take a non-const reference) as an implicit
6106 // -- not have default arguments.
6107 unsigned ExpectedParams = 1;
6108 if (CSM == CXXDefaultConstructor || CSM == CXXDestructor)
6110 if (MD->getNumParams() != ExpectedParams) {
6111 // This also checks for default arguments: a copy or move constructor with a
6112 // default argument is classified as a default constructor, and assignment
6113 // operations and destructors can't have default arguments.
6114 Diag(MD->getLocation(), diag::err_defaulted_special_member_params)
6115 << CSM << MD->getSourceRange();
6117 } else if (MD->isVariadic()) {
6118 Diag(MD->getLocation(), diag::err_defaulted_special_member_variadic)
6119 << CSM << MD->getSourceRange();
6123 const FunctionProtoType *Type = MD->getType()->getAs<FunctionProtoType>();
6125 bool CanHaveConstParam = false;
6126 if (CSM == CXXCopyConstructor)
6127 CanHaveConstParam = RD->implicitCopyConstructorHasConstParam();
6128 else if (CSM == CXXCopyAssignment)
6129 CanHaveConstParam = RD->implicitCopyAssignmentHasConstParam();
6131 QualType ReturnType = Context.VoidTy;
6132 if (CSM == CXXCopyAssignment || CSM == CXXMoveAssignment) {
6133 // Check for return type matching.
6134 ReturnType = Type->getReturnType();
6135 QualType ExpectedReturnType =
6136 Context.getLValueReferenceType(Context.getTypeDeclType(RD));
6137 if (!Context.hasSameType(ReturnType, ExpectedReturnType)) {
6138 Diag(MD->getLocation(), diag::err_defaulted_special_member_return_type)
6139 << (CSM == CXXMoveAssignment) << ExpectedReturnType;
6143 // A defaulted special member cannot have cv-qualifiers.
6144 if (Type->getTypeQuals()) {
6145 Diag(MD->getLocation(), diag::err_defaulted_special_member_quals)
6146 << (CSM == CXXMoveAssignment) << getLangOpts().CPlusPlus14;
6151 // Check for parameter type matching.
6152 QualType ArgType = ExpectedParams ? Type->getParamType(0) : QualType();
6153 bool HasConstParam = false;
6154 if (ExpectedParams && ArgType->isReferenceType()) {
6155 // Argument must be reference to possibly-const T.
6156 QualType ReferentType = ArgType->getPointeeType();
6157 HasConstParam = ReferentType.isConstQualified();
6159 if (ReferentType.isVolatileQualified()) {
6160 Diag(MD->getLocation(),
6161 diag::err_defaulted_special_member_volatile_param) << CSM;
6165 if (HasConstParam && !CanHaveConstParam) {
6166 if (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment) {
6167 Diag(MD->getLocation(),
6168 diag::err_defaulted_special_member_copy_const_param)
6169 << (CSM == CXXCopyAssignment);
6170 // FIXME: Explain why this special member can't be const.
6172 Diag(MD->getLocation(),
6173 diag::err_defaulted_special_member_move_const_param)
6174 << (CSM == CXXMoveAssignment);
6178 } else if (ExpectedParams) {
6179 // A copy assignment operator can take its argument by value, but a
6180 // defaulted one cannot.
6181 assert(CSM == CXXCopyAssignment && "unexpected non-ref argument");
6182 Diag(MD->getLocation(), diag::err_defaulted_copy_assign_not_ref);
6186 // C++11 [dcl.fct.def.default]p2:
6187 // An explicitly-defaulted function may be declared constexpr only if it
6188 // would have been implicitly declared as constexpr,
6189 // Do not apply this rule to members of class templates, since core issue 1358
6190 // makes such functions always instantiate to constexpr functions. For
6191 // functions which cannot be constexpr (for non-constructors in C++11 and for
6192 // destructors in C++1y), this is checked elsewhere.
6193 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, RD, CSM,
6195 if ((getLangOpts().CPlusPlus14 ? !isa<CXXDestructorDecl>(MD)
6196 : isa<CXXConstructorDecl>(MD)) &&
6197 MD->isConstexpr() && !Constexpr &&
6198 MD->getTemplatedKind() == FunctionDecl::TK_NonTemplate) {
6199 Diag(MD->getLocStart(), diag::err_incorrect_defaulted_constexpr) << CSM;
6200 // FIXME: Explain why the special member can't be constexpr.
6204 // and may have an explicit exception-specification only if it is compatible
6205 // with the exception-specification on the implicit declaration.
6206 if (Type->hasExceptionSpec()) {
6207 // Delay the check if this is the first declaration of the special member,
6208 // since we may not have parsed some necessary in-class initializers yet.
6210 // If the exception specification needs to be instantiated, do so now,
6211 // before we clobber it with an EST_Unevaluated specification below.
6212 if (Type->getExceptionSpecType() == EST_Uninstantiated) {
6213 InstantiateExceptionSpec(MD->getLocStart(), MD);
6214 Type = MD->getType()->getAs<FunctionProtoType>();
6216 DelayedDefaultedMemberExceptionSpecs.push_back(std::make_pair(MD, Type));
6218 CheckExplicitlyDefaultedMemberExceptionSpec(MD, Type);
6221 // If a function is explicitly defaulted on its first declaration,
6223 // -- it is implicitly considered to be constexpr if the implicit
6224 // definition would be,
6225 MD->setConstexpr(Constexpr);
6227 // -- it is implicitly considered to have the same exception-specification
6228 // as if it had been implicitly declared,
6229 FunctionProtoType::ExtProtoInfo EPI = Type->getExtProtoInfo();
6230 EPI.ExceptionSpec.Type = EST_Unevaluated;
6231 EPI.ExceptionSpec.SourceDecl = MD;
6232 MD->setType(Context.getFunctionType(ReturnType,
6233 llvm::makeArrayRef(&ArgType,
6238 if (ShouldDeleteSpecialMember(MD, CSM)) {
6240 SetDeclDeleted(MD, MD->getLocation());
6242 // C++11 [dcl.fct.def.default]p4:
6243 // [For a] user-provided explicitly-defaulted function [...] if such a
6244 // function is implicitly defined as deleted, the program is ill-formed.
6245 Diag(MD->getLocation(), diag::err_out_of_line_default_deletes) << CSM;
6246 ShouldDeleteSpecialMember(MD, CSM, nullptr, /*Diagnose*/true);
6252 MD->setInvalidDecl();
6255 /// Check whether the exception specification provided for an
6256 /// explicitly-defaulted special member matches the exception specification
6257 /// that would have been generated for an implicit special member, per
6258 /// C++11 [dcl.fct.def.default]p2.
6259 void Sema::CheckExplicitlyDefaultedMemberExceptionSpec(
6260 CXXMethodDecl *MD, const FunctionProtoType *SpecifiedType) {
6261 // If the exception specification was explicitly specified but hadn't been
6262 // parsed when the method was defaulted, grab it now.
6263 if (SpecifiedType->getExceptionSpecType() == EST_Unparsed)
6265 MD->getTypeSourceInfo()->getType()->castAs<FunctionProtoType>();
6267 // Compute the implicit exception specification.
6268 CallingConv CC = Context.getDefaultCallingConvention(/*IsVariadic=*/false,
6269 /*IsCXXMethod=*/true);
6270 FunctionProtoType::ExtProtoInfo EPI(CC);
6271 auto IES = computeImplicitExceptionSpec(*this, MD->getLocation(), MD);
6272 EPI.ExceptionSpec = IES.getExceptionSpec();
6273 const FunctionProtoType *ImplicitType = cast<FunctionProtoType>(
6274 Context.getFunctionType(Context.VoidTy, None, EPI));
6276 // Ensure that it matches.
6277 CheckEquivalentExceptionSpec(
6278 PDiag(diag::err_incorrect_defaulted_exception_spec)
6279 << getSpecialMember(MD), PDiag(),
6280 ImplicitType, SourceLocation(),
6281 SpecifiedType, MD->getLocation());
6284 void Sema::CheckDelayedMemberExceptionSpecs() {
6285 decltype(DelayedExceptionSpecChecks) Checks;
6286 decltype(DelayedDefaultedMemberExceptionSpecs) Specs;
6288 std::swap(Checks, DelayedExceptionSpecChecks);
6289 std::swap(Specs, DelayedDefaultedMemberExceptionSpecs);
6291 // Perform any deferred checking of exception specifications for virtual
6293 for (auto &Check : Checks)
6294 CheckOverridingFunctionExceptionSpec(Check.first, Check.second);
6296 // Check that any explicitly-defaulted methods have exception specifications
6297 // compatible with their implicit exception specifications.
6298 for (auto &Spec : Specs)
6299 CheckExplicitlyDefaultedMemberExceptionSpec(Spec.first, Spec.second);
6303 struct SpecialMemberDeletionInfo {
6306 Sema::CXXSpecialMember CSM;
6307 Sema::InheritedConstructorInfo *ICI;
6310 // Properties of the special member, computed for convenience.
6311 bool IsConstructor, IsAssignment, IsMove, ConstArg;
6314 bool AllFieldsAreConst;
6316 SpecialMemberDeletionInfo(Sema &S, CXXMethodDecl *MD,
6317 Sema::CXXSpecialMember CSM,
6318 Sema::InheritedConstructorInfo *ICI, bool Diagnose)
6319 : S(S), MD(MD), CSM(CSM), ICI(ICI), Diagnose(Diagnose),
6320 IsConstructor(false), IsAssignment(false), IsMove(false),
6321 ConstArg(false), Loc(MD->getLocation()), AllFieldsAreConst(true) {
6323 case Sema::CXXDefaultConstructor:
6324 case Sema::CXXCopyConstructor:
6325 IsConstructor = true;
6327 case Sema::CXXMoveConstructor:
6328 IsConstructor = true;
6331 case Sema::CXXCopyAssignment:
6332 IsAssignment = true;
6334 case Sema::CXXMoveAssignment:
6335 IsAssignment = true;
6338 case Sema::CXXDestructor:
6340 case Sema::CXXInvalid:
6341 llvm_unreachable("invalid special member kind");
6344 if (MD->getNumParams()) {
6345 if (const ReferenceType *RT =
6346 MD->getParamDecl(0)->getType()->getAs<ReferenceType>())
6347 ConstArg = RT->getPointeeType().isConstQualified();
6351 bool inUnion() const { return MD->getParent()->isUnion(); }
6353 Sema::CXXSpecialMember getEffectiveCSM() {
6354 return ICI ? Sema::CXXInvalid : CSM;
6357 /// Look up the corresponding special member in the given class.
6358 Sema::SpecialMemberOverloadResult *lookupIn(CXXRecordDecl *Class,
6359 unsigned Quals, bool IsMutable) {
6360 return lookupCallFromSpecialMember(S, Class, CSM, Quals,
6361 ConstArg && !IsMutable);
6364 typedef llvm::PointerUnion<CXXBaseSpecifier*, FieldDecl*> Subobject;
6366 bool shouldDeleteForBase(CXXBaseSpecifier *Base);
6367 bool shouldDeleteForField(FieldDecl *FD);
6368 bool shouldDeleteForAllConstMembers();
6370 bool shouldDeleteForClassSubobject(CXXRecordDecl *Class, Subobject Subobj,
6372 bool shouldDeleteForSubobjectCall(Subobject Subobj,
6373 Sema::SpecialMemberOverloadResult *SMOR,
6374 bool IsDtorCallInCtor);
6376 bool isAccessible(Subobject Subobj, CXXMethodDecl *D);
6380 /// Is the given special member inaccessible when used on the given
6382 bool SpecialMemberDeletionInfo::isAccessible(Subobject Subobj,
6383 CXXMethodDecl *target) {
6384 /// If we're operating on a base class, the object type is the
6385 /// type of this special member.
6387 AccessSpecifier access = target->getAccess();
6388 if (CXXBaseSpecifier *base = Subobj.dyn_cast<CXXBaseSpecifier*>()) {
6389 objectTy = S.Context.getTypeDeclType(MD->getParent());
6390 access = CXXRecordDecl::MergeAccess(base->getAccessSpecifier(), access);
6392 // If we're operating on a field, the object type is the type of the field.
6394 objectTy = S.Context.getTypeDeclType(target->getParent());
6397 return S.isSpecialMemberAccessibleForDeletion(target, access, objectTy);
6400 /// Check whether we should delete a special member due to the implicit
6401 /// definition containing a call to a special member of a subobject.
6402 bool SpecialMemberDeletionInfo::shouldDeleteForSubobjectCall(
6403 Subobject Subobj, Sema::SpecialMemberOverloadResult *SMOR,
6404 bool IsDtorCallInCtor) {
6405 CXXMethodDecl *Decl = SMOR->getMethod();
6406 FieldDecl *Field = Subobj.dyn_cast<FieldDecl*>();
6410 if (SMOR->getKind() == Sema::SpecialMemberOverloadResult::NoMemberOrDeleted)
6411 DiagKind = !Decl ? 0 : 1;
6412 else if (SMOR->getKind() == Sema::SpecialMemberOverloadResult::Ambiguous)
6414 else if (!isAccessible(Subobj, Decl))
6416 else if (!IsDtorCallInCtor && Field && Field->getParent()->isUnion() &&
6417 !Decl->isTrivial()) {
6418 // A member of a union must have a trivial corresponding special member.
6419 // As a weird special case, a destructor call from a union's constructor
6420 // must be accessible and non-deleted, but need not be trivial. Such a
6421 // destructor is never actually called, but is semantically checked as
6431 S.Diag(Field->getLocation(),
6432 diag::note_deleted_special_member_class_subobject)
6433 << getEffectiveCSM() << MD->getParent() << /*IsField*/true
6434 << Field << DiagKind << IsDtorCallInCtor;
6436 CXXBaseSpecifier *Base = Subobj.get<CXXBaseSpecifier*>();
6437 S.Diag(Base->getLocStart(),
6438 diag::note_deleted_special_member_class_subobject)
6439 << getEffectiveCSM() << MD->getParent() << /*IsField*/false
6440 << Base->getType() << DiagKind << IsDtorCallInCtor;
6444 S.NoteDeletedFunction(Decl);
6445 // FIXME: Explain inaccessibility if DiagKind == 3.
6451 /// Check whether we should delete a special member function due to having a
6452 /// direct or virtual base class or non-static data member of class type M.
6453 bool SpecialMemberDeletionInfo::shouldDeleteForClassSubobject(
6454 CXXRecordDecl *Class, Subobject Subobj, unsigned Quals) {
6455 FieldDecl *Field = Subobj.dyn_cast<FieldDecl*>();
6456 bool IsMutable = Field && Field->isMutable();
6458 // C++11 [class.ctor]p5:
6459 // -- any direct or virtual base class, or non-static data member with no
6460 // brace-or-equal-initializer, has class type M (or array thereof) and
6461 // either M has no default constructor or overload resolution as applied
6462 // to M's default constructor results in an ambiguity or in a function
6463 // that is deleted or inaccessible
6464 // C++11 [class.copy]p11, C++11 [class.copy]p23:
6465 // -- a direct or virtual base class B that cannot be copied/moved because
6466 // overload resolution, as applied to B's corresponding special member,
6467 // results in an ambiguity or a function that is deleted or inaccessible
6468 // from the defaulted special member
6469 // C++11 [class.dtor]p5:
6470 // -- any direct or virtual base class [...] has a type with a destructor
6471 // that is deleted or inaccessible
6472 if (!(CSM == Sema::CXXDefaultConstructor &&
6473 Field && Field->hasInClassInitializer()) &&
6474 shouldDeleteForSubobjectCall(Subobj, lookupIn(Class, Quals, IsMutable),
6478 // C++11 [class.ctor]p5, C++11 [class.copy]p11:
6479 // -- any direct or virtual base class or non-static data member has a
6480 // type with a destructor that is deleted or inaccessible
6481 if (IsConstructor) {
6482 Sema::SpecialMemberOverloadResult *SMOR =
6483 S.LookupSpecialMember(Class, Sema::CXXDestructor,
6484 false, false, false, false, false);
6485 if (shouldDeleteForSubobjectCall(Subobj, SMOR, true))
6492 /// Check whether we should delete a special member function due to the class
6493 /// having a particular direct or virtual base class.
6494 bool SpecialMemberDeletionInfo::shouldDeleteForBase(CXXBaseSpecifier *Base) {
6495 CXXRecordDecl *BaseClass = Base->getType()->getAsCXXRecordDecl();
6496 // If program is correct, BaseClass cannot be null, but if it is, the error
6497 // must be reported elsewhere.
6500 // If we have an inheriting constructor, check whether we're calling an
6501 // inherited constructor instead of a default constructor.
6503 assert(CSM == Sema::CXXDefaultConstructor);
6505 ICI->findConstructorForBase(BaseClass, cast<CXXConstructorDecl>(MD)
6506 ->getInheritedConstructor()
6510 if (BaseCtor->isDeleted() && Diagnose) {
6511 S.Diag(Base->getLocStart(),
6512 diag::note_deleted_special_member_class_subobject)
6513 << getEffectiveCSM() << MD->getParent() << /*IsField*/false
6514 << Base->getType() << /*Deleted*/1 << /*IsDtorCallInCtor*/false;
6515 S.NoteDeletedFunction(BaseCtor);
6517 return BaseCtor->isDeleted();
6520 return shouldDeleteForClassSubobject(BaseClass, Base, 0);
6523 /// Check whether we should delete a special member function due to the class
6524 /// having a particular non-static data member.
6525 bool SpecialMemberDeletionInfo::shouldDeleteForField(FieldDecl *FD) {
6526 QualType FieldType = S.Context.getBaseElementType(FD->getType());
6527 CXXRecordDecl *FieldRecord = FieldType->getAsCXXRecordDecl();
6529 if (CSM == Sema::CXXDefaultConstructor) {
6530 // For a default constructor, all references must be initialized in-class
6531 // and, if a union, it must have a non-const member.
6532 if (FieldType->isReferenceType() && !FD->hasInClassInitializer()) {
6534 S.Diag(FD->getLocation(), diag::note_deleted_default_ctor_uninit_field)
6535 << !!ICI << MD->getParent() << FD << FieldType << /*Reference*/0;
6538 // C++11 [class.ctor]p5: any non-variant non-static data member of
6539 // const-qualified type (or array thereof) with no
6540 // brace-or-equal-initializer does not have a user-provided default
6542 if (!inUnion() && FieldType.isConstQualified() &&
6543 !FD->hasInClassInitializer() &&
6544 (!FieldRecord || !FieldRecord->hasUserProvidedDefaultConstructor())) {
6546 S.Diag(FD->getLocation(), diag::note_deleted_default_ctor_uninit_field)
6547 << !!ICI << MD->getParent() << FD << FD->getType() << /*Const*/1;
6551 if (inUnion() && !FieldType.isConstQualified())
6552 AllFieldsAreConst = false;
6553 } else if (CSM == Sema::CXXCopyConstructor) {
6554 // For a copy constructor, data members must not be of rvalue reference
6556 if (FieldType->isRValueReferenceType()) {
6558 S.Diag(FD->getLocation(), diag::note_deleted_copy_ctor_rvalue_reference)
6559 << MD->getParent() << FD << FieldType;
6562 } else if (IsAssignment) {
6563 // For an assignment operator, data members must not be of reference type.
6564 if (FieldType->isReferenceType()) {
6566 S.Diag(FD->getLocation(), diag::note_deleted_assign_field)
6567 << IsMove << MD->getParent() << FD << FieldType << /*Reference*/0;
6570 if (!FieldRecord && FieldType.isConstQualified()) {
6571 // C++11 [class.copy]p23:
6572 // -- a non-static data member of const non-class type (or array thereof)
6574 S.Diag(FD->getLocation(), diag::note_deleted_assign_field)
6575 << IsMove << MD->getParent() << FD << FD->getType() << /*Const*/1;
6581 // Some additional restrictions exist on the variant members.
6582 if (!inUnion() && FieldRecord->isUnion() &&
6583 FieldRecord->isAnonymousStructOrUnion()) {
6584 bool AllVariantFieldsAreConst = true;
6586 // FIXME: Handle anonymous unions declared within anonymous unions.
6587 for (auto *UI : FieldRecord->fields()) {
6588 QualType UnionFieldType = S.Context.getBaseElementType(UI->getType());
6590 if (!UnionFieldType.isConstQualified())
6591 AllVariantFieldsAreConst = false;
6593 CXXRecordDecl *UnionFieldRecord = UnionFieldType->getAsCXXRecordDecl();
6594 if (UnionFieldRecord &&
6595 shouldDeleteForClassSubobject(UnionFieldRecord, UI,
6596 UnionFieldType.getCVRQualifiers()))
6600 // At least one member in each anonymous union must be non-const
6601 if (CSM == Sema::CXXDefaultConstructor && AllVariantFieldsAreConst &&
6602 !FieldRecord->field_empty()) {
6604 S.Diag(FieldRecord->getLocation(),
6605 diag::note_deleted_default_ctor_all_const)
6606 << !!ICI << MD->getParent() << /*anonymous union*/1;
6610 // Don't check the implicit member of the anonymous union type.
6611 // This is technically non-conformant, but sanity demands it.
6615 if (shouldDeleteForClassSubobject(FieldRecord, FD,
6616 FieldType.getCVRQualifiers()))
6623 /// C++11 [class.ctor] p5:
6624 /// A defaulted default constructor for a class X is defined as deleted if
6625 /// X is a union and all of its variant members are of const-qualified type.
6626 bool SpecialMemberDeletionInfo::shouldDeleteForAllConstMembers() {
6627 // This is a silly definition, because it gives an empty union a deleted
6628 // default constructor. Don't do that.
6629 if (CSM == Sema::CXXDefaultConstructor && inUnion() && AllFieldsAreConst) {
6630 bool AnyFields = false;
6631 for (auto *F : MD->getParent()->fields())
6632 if ((AnyFields = !F->isUnnamedBitfield()))
6637 S.Diag(MD->getParent()->getLocation(),
6638 diag::note_deleted_default_ctor_all_const)
6639 << !!ICI << MD->getParent() << /*not anonymous union*/0;
6645 /// Determine whether a defaulted special member function should be defined as
6646 /// deleted, as specified in C++11 [class.ctor]p5, C++11 [class.copy]p11,
6647 /// C++11 [class.copy]p23, and C++11 [class.dtor]p5.
6648 bool Sema::ShouldDeleteSpecialMember(CXXMethodDecl *MD, CXXSpecialMember CSM,
6649 InheritedConstructorInfo *ICI,
6651 if (MD->isInvalidDecl())
6653 CXXRecordDecl *RD = MD->getParent();
6654 assert(!RD->isDependentType() && "do deletion after instantiation");
6655 if (!LangOpts.CPlusPlus11 || RD->isInvalidDecl())
6658 // C++11 [expr.lambda.prim]p19:
6659 // The closure type associated with a lambda-expression has a
6660 // deleted (8.4.3) default constructor and a deleted copy
6661 // assignment operator.
6662 if (RD->isLambda() &&
6663 (CSM == CXXDefaultConstructor || CSM == CXXCopyAssignment)) {
6665 Diag(RD->getLocation(), diag::note_lambda_decl);
6669 // For an anonymous struct or union, the copy and assignment special members
6670 // will never be used, so skip the check. For an anonymous union declared at
6671 // namespace scope, the constructor and destructor are used.
6672 if (CSM != CXXDefaultConstructor && CSM != CXXDestructor &&
6673 RD->isAnonymousStructOrUnion())
6676 // C++11 [class.copy]p7, p18:
6677 // If the class definition declares a move constructor or move assignment
6678 // operator, an implicitly declared copy constructor or copy assignment
6679 // operator is defined as deleted.
6680 if (MD->isImplicit() &&
6681 (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment)) {
6682 CXXMethodDecl *UserDeclaredMove = nullptr;
6684 // In Microsoft mode up to MSVC 2013, a user-declared move only causes the
6685 // deletion of the corresponding copy operation, not both copy operations.
6686 // MSVC 2015 has adopted the standards conforming behavior.
6687 bool DeletesOnlyMatchingCopy =
6688 getLangOpts().MSVCCompat &&
6689 !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015);
6691 if (RD->hasUserDeclaredMoveConstructor() &&
6692 (!DeletesOnlyMatchingCopy || CSM == CXXCopyConstructor)) {
6693 if (!Diagnose) return true;
6695 // Find any user-declared move constructor.
6696 for (auto *I : RD->ctors()) {
6697 if (I->isMoveConstructor()) {
6698 UserDeclaredMove = I;
6702 assert(UserDeclaredMove);
6703 } else if (RD->hasUserDeclaredMoveAssignment() &&
6704 (!DeletesOnlyMatchingCopy || CSM == CXXCopyAssignment)) {
6705 if (!Diagnose) return true;
6707 // Find any user-declared move assignment operator.
6708 for (auto *I : RD->methods()) {
6709 if (I->isMoveAssignmentOperator()) {
6710 UserDeclaredMove = I;
6714 assert(UserDeclaredMove);
6717 if (UserDeclaredMove) {
6718 Diag(UserDeclaredMove->getLocation(),
6719 diag::note_deleted_copy_user_declared_move)
6720 << (CSM == CXXCopyAssignment) << RD
6721 << UserDeclaredMove->isMoveAssignmentOperator();
6726 // Do access control from the special member function
6727 ContextRAII MethodContext(*this, MD);
6729 // C++11 [class.dtor]p5:
6730 // -- for a virtual destructor, lookup of the non-array deallocation function
6731 // results in an ambiguity or in a function that is deleted or inaccessible
6732 if (CSM == CXXDestructor && MD->isVirtual()) {
6733 FunctionDecl *OperatorDelete = nullptr;
6734 DeclarationName Name =
6735 Context.DeclarationNames.getCXXOperatorName(OO_Delete);
6736 if (FindDeallocationFunction(MD->getLocation(), MD->getParent(), Name,
6737 OperatorDelete, /*Diagnose*/false)) {
6739 Diag(RD->getLocation(), diag::note_deleted_dtor_no_operator_delete);
6744 SpecialMemberDeletionInfo SMI(*this, MD, CSM, ICI, Diagnose);
6746 for (auto &BI : RD->bases())
6747 if ((SMI.IsAssignment || !BI.isVirtual()) &&
6748 SMI.shouldDeleteForBase(&BI))
6751 // Per DR1611, do not consider virtual bases of constructors of abstract
6752 // classes, since we are not going to construct them. For assignment
6753 // operators, we only assign (and thus only consider) direct bases.
6754 if ((!RD->isAbstract() || !SMI.IsConstructor) && !SMI.IsAssignment) {
6755 for (auto &BI : RD->vbases())
6756 if (SMI.shouldDeleteForBase(&BI))
6760 for (auto *FI : RD->fields())
6761 if (!FI->isInvalidDecl() && !FI->isUnnamedBitfield() &&
6762 SMI.shouldDeleteForField(FI))
6765 if (SMI.shouldDeleteForAllConstMembers())
6768 if (getLangOpts().CUDA) {
6769 // We should delete the special member in CUDA mode if target inference
6771 return inferCUDATargetForImplicitSpecialMember(RD, CSM, MD, SMI.ConstArg,
6778 /// Perform lookup for a special member of the specified kind, and determine
6779 /// whether it is trivial. If the triviality can be determined without the
6780 /// lookup, skip it. This is intended for use when determining whether a
6781 /// special member of a containing object is trivial, and thus does not ever
6782 /// perform overload resolution for default constructors.
6784 /// If \p Selected is not \c NULL, \c *Selected will be filled in with the
6785 /// member that was most likely to be intended to be trivial, if any.
6786 static bool findTrivialSpecialMember(Sema &S, CXXRecordDecl *RD,
6787 Sema::CXXSpecialMember CSM, unsigned Quals,
6788 bool ConstRHS, CXXMethodDecl **Selected) {
6790 *Selected = nullptr;
6793 case Sema::CXXInvalid:
6794 llvm_unreachable("not a special member");
6796 case Sema::CXXDefaultConstructor:
6797 // C++11 [class.ctor]p5:
6798 // A default constructor is trivial if:
6799 // - all the [direct subobjects] have trivial default constructors
6801 // Note, no overload resolution is performed in this case.
6802 if (RD->hasTrivialDefaultConstructor())
6806 // If there's a default constructor which could have been trivial, dig it
6807 // out. Otherwise, if there's any user-provided default constructor, point
6808 // to that as an example of why there's not a trivial one.
6809 CXXConstructorDecl *DefCtor = nullptr;
6810 if (RD->needsImplicitDefaultConstructor())
6811 S.DeclareImplicitDefaultConstructor(RD);
6812 for (auto *CI : RD->ctors()) {
6813 if (!CI->isDefaultConstructor())
6816 if (!DefCtor->isUserProvided())
6820 *Selected = DefCtor;
6825 case Sema::CXXDestructor:
6826 // C++11 [class.dtor]p5:
6827 // A destructor is trivial if:
6828 // - all the direct [subobjects] have trivial destructors
6829 if (RD->hasTrivialDestructor())
6833 if (RD->needsImplicitDestructor())
6834 S.DeclareImplicitDestructor(RD);
6835 *Selected = RD->getDestructor();
6840 case Sema::CXXCopyConstructor:
6841 // C++11 [class.copy]p12:
6842 // A copy constructor is trivial if:
6843 // - the constructor selected to copy each direct [subobject] is trivial
6844 if (RD->hasTrivialCopyConstructor()) {
6845 if (Quals == Qualifiers::Const)
6846 // We must either select the trivial copy constructor or reach an
6847 // ambiguity; no need to actually perform overload resolution.
6849 } else if (!Selected) {
6852 // In C++98, we are not supposed to perform overload resolution here, but we
6853 // treat that as a language defect, as suggested on cxx-abi-dev, to treat
6854 // cases like B as having a non-trivial copy constructor:
6855 // struct A { template<typename T> A(T&); };
6856 // struct B { mutable A a; };
6857 goto NeedOverloadResolution;
6859 case Sema::CXXCopyAssignment:
6860 // C++11 [class.copy]p25:
6861 // A copy assignment operator is trivial if:
6862 // - the assignment operator selected to copy each direct [subobject] is
6864 if (RD->hasTrivialCopyAssignment()) {
6865 if (Quals == Qualifiers::Const)
6867 } else if (!Selected) {
6870 // In C++98, we are not supposed to perform overload resolution here, but we
6871 // treat that as a language defect.
6872 goto NeedOverloadResolution;
6874 case Sema::CXXMoveConstructor:
6875 case Sema::CXXMoveAssignment:
6876 NeedOverloadResolution:
6877 Sema::SpecialMemberOverloadResult *SMOR =
6878 lookupCallFromSpecialMember(S, RD, CSM, Quals, ConstRHS);
6880 // The standard doesn't describe how to behave if the lookup is ambiguous.
6881 // We treat it as not making the member non-trivial, just like the standard
6882 // mandates for the default constructor. This should rarely matter, because
6883 // the member will also be deleted.
6884 if (SMOR->getKind() == Sema::SpecialMemberOverloadResult::Ambiguous)
6887 if (!SMOR->getMethod()) {
6888 assert(SMOR->getKind() ==
6889 Sema::SpecialMemberOverloadResult::NoMemberOrDeleted);
6893 // We deliberately don't check if we found a deleted special member. We're
6896 *Selected = SMOR->getMethod();
6897 return SMOR->getMethod()->isTrivial();
6900 llvm_unreachable("unknown special method kind");
6903 static CXXConstructorDecl *findUserDeclaredCtor(CXXRecordDecl *RD) {
6904 for (auto *CI : RD->ctors())
6905 if (!CI->isImplicit())
6908 // Look for constructor templates.
6909 typedef CXXRecordDecl::specific_decl_iterator<FunctionTemplateDecl> tmpl_iter;
6910 for (tmpl_iter TI(RD->decls_begin()), TE(RD->decls_end()); TI != TE; ++TI) {
6911 if (CXXConstructorDecl *CD =
6912 dyn_cast<CXXConstructorDecl>(TI->getTemplatedDecl()))
6919 /// The kind of subobject we are checking for triviality. The values of this
6920 /// enumeration are used in diagnostics.
6921 enum TrivialSubobjectKind {
6922 /// The subobject is a base class.
6924 /// The subobject is a non-static data member.
6926 /// The object is actually the complete object.
6930 /// Check whether the special member selected for a given type would be trivial.
6931 static bool checkTrivialSubobjectCall(Sema &S, SourceLocation SubobjLoc,
6932 QualType SubType, bool ConstRHS,
6933 Sema::CXXSpecialMember CSM,
6934 TrivialSubobjectKind Kind,
6936 CXXRecordDecl *SubRD = SubType->getAsCXXRecordDecl();
6940 CXXMethodDecl *Selected;
6941 if (findTrivialSpecialMember(S, SubRD, CSM, SubType.getCVRQualifiers(),
6942 ConstRHS, Diagnose ? &Selected : nullptr))
6949 if (!Selected && CSM == Sema::CXXDefaultConstructor) {
6950 S.Diag(SubobjLoc, diag::note_nontrivial_no_def_ctor)
6951 << Kind << SubType.getUnqualifiedType();
6952 if (CXXConstructorDecl *CD = findUserDeclaredCtor(SubRD))
6953 S.Diag(CD->getLocation(), diag::note_user_declared_ctor);
6954 } else if (!Selected)
6955 S.Diag(SubobjLoc, diag::note_nontrivial_no_copy)
6956 << Kind << SubType.getUnqualifiedType() << CSM << SubType;
6957 else if (Selected->isUserProvided()) {
6958 if (Kind == TSK_CompleteObject)
6959 S.Diag(Selected->getLocation(), diag::note_nontrivial_user_provided)
6960 << Kind << SubType.getUnqualifiedType() << CSM;
6962 S.Diag(SubobjLoc, diag::note_nontrivial_user_provided)
6963 << Kind << SubType.getUnqualifiedType() << CSM;
6964 S.Diag(Selected->getLocation(), diag::note_declared_at);
6967 if (Kind != TSK_CompleteObject)
6968 S.Diag(SubobjLoc, diag::note_nontrivial_subobject)
6969 << Kind << SubType.getUnqualifiedType() << CSM;
6971 // Explain why the defaulted or deleted special member isn't trivial.
6972 S.SpecialMemberIsTrivial(Selected, CSM, Diagnose);
6979 /// Check whether the members of a class type allow a special member to be
6981 static bool checkTrivialClassMembers(Sema &S, CXXRecordDecl *RD,
6982 Sema::CXXSpecialMember CSM,
6983 bool ConstArg, bool Diagnose) {
6984 for (const auto *FI : RD->fields()) {
6985 if (FI->isInvalidDecl() || FI->isUnnamedBitfield())
6988 QualType FieldType = S.Context.getBaseElementType(FI->getType());
6990 // Pretend anonymous struct or union members are members of this class.
6991 if (FI->isAnonymousStructOrUnion()) {
6992 if (!checkTrivialClassMembers(S, FieldType->getAsCXXRecordDecl(),
6993 CSM, ConstArg, Diagnose))
6998 // C++11 [class.ctor]p5:
6999 // A default constructor is trivial if [...]
7000 // -- no non-static data member of its class has a
7001 // brace-or-equal-initializer
7002 if (CSM == Sema::CXXDefaultConstructor && FI->hasInClassInitializer()) {
7004 S.Diag(FI->getLocation(), diag::note_nontrivial_in_class_init) << FI;
7008 // Objective C ARC 4.3.5:
7009 // [...] nontrivally ownership-qualified types are [...] not trivially
7010 // default constructible, copy constructible, move constructible, copy
7011 // assignable, move assignable, or destructible [...]
7012 if (S.getLangOpts().ObjCAutoRefCount &&
7013 FieldType.hasNonTrivialObjCLifetime()) {
7015 S.Diag(FI->getLocation(), diag::note_nontrivial_objc_ownership)
7016 << RD << FieldType.getObjCLifetime();
7020 bool ConstRHS = ConstArg && !FI->isMutable();
7021 if (!checkTrivialSubobjectCall(S, FI->getLocation(), FieldType, ConstRHS,
7022 CSM, TSK_Field, Diagnose))
7029 /// Diagnose why the specified class does not have a trivial special member of
7031 void Sema::DiagnoseNontrivial(const CXXRecordDecl *RD, CXXSpecialMember CSM) {
7032 QualType Ty = Context.getRecordType(RD);
7034 bool ConstArg = (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment);
7035 checkTrivialSubobjectCall(*this, RD->getLocation(), Ty, ConstArg, CSM,
7036 TSK_CompleteObject, /*Diagnose*/true);
7039 /// Determine whether a defaulted or deleted special member function is trivial,
7040 /// as specified in C++11 [class.ctor]p5, C++11 [class.copy]p12,
7041 /// C++11 [class.copy]p25, and C++11 [class.dtor]p5.
7042 bool Sema::SpecialMemberIsTrivial(CXXMethodDecl *MD, CXXSpecialMember CSM,
7044 assert(!MD->isUserProvided() && CSM != CXXInvalid && "not special enough");
7046 CXXRecordDecl *RD = MD->getParent();
7048 bool ConstArg = false;
7050 // C++11 [class.copy]p12, p25: [DR1593]
7051 // A [special member] is trivial if [...] its parameter-type-list is
7052 // equivalent to the parameter-type-list of an implicit declaration [...]
7054 case CXXDefaultConstructor:
7056 // Trivial default constructors and destructors cannot have parameters.
7059 case CXXCopyConstructor:
7060 case CXXCopyAssignment: {
7061 // Trivial copy operations always have const, non-volatile parameter types.
7063 const ParmVarDecl *Param0 = MD->getParamDecl(0);
7064 const ReferenceType *RT = Param0->getType()->getAs<ReferenceType>();
7065 if (!RT || RT->getPointeeType().getCVRQualifiers() != Qualifiers::Const) {
7067 Diag(Param0->getLocation(), diag::note_nontrivial_param_type)
7068 << Param0->getSourceRange() << Param0->getType()
7069 << Context.getLValueReferenceType(
7070 Context.getRecordType(RD).withConst());
7076 case CXXMoveConstructor:
7077 case CXXMoveAssignment: {
7078 // Trivial move operations always have non-cv-qualified parameters.
7079 const ParmVarDecl *Param0 = MD->getParamDecl(0);
7080 const RValueReferenceType *RT =
7081 Param0->getType()->getAs<RValueReferenceType>();
7082 if (!RT || RT->getPointeeType().getCVRQualifiers()) {
7084 Diag(Param0->getLocation(), diag::note_nontrivial_param_type)
7085 << Param0->getSourceRange() << Param0->getType()
7086 << Context.getRValueReferenceType(Context.getRecordType(RD));
7093 llvm_unreachable("not a special member");
7096 if (MD->getMinRequiredArguments() < MD->getNumParams()) {
7098 Diag(MD->getParamDecl(MD->getMinRequiredArguments())->getLocation(),
7099 diag::note_nontrivial_default_arg)
7100 << MD->getParamDecl(MD->getMinRequiredArguments())->getSourceRange();
7103 if (MD->isVariadic()) {
7105 Diag(MD->getLocation(), diag::note_nontrivial_variadic);
7109 // C++11 [class.ctor]p5, C++11 [class.dtor]p5:
7110 // A copy/move [constructor or assignment operator] is trivial if
7111 // -- the [member] selected to copy/move each direct base class subobject
7114 // C++11 [class.copy]p12, C++11 [class.copy]p25:
7115 // A [default constructor or destructor] is trivial if
7116 // -- all the direct base classes have trivial [default constructors or
7118 for (const auto &BI : RD->bases())
7119 if (!checkTrivialSubobjectCall(*this, BI.getLocStart(), BI.getType(),
7120 ConstArg, CSM, TSK_BaseClass, Diagnose))
7123 // C++11 [class.ctor]p5, C++11 [class.dtor]p5:
7124 // A copy/move [constructor or assignment operator] for a class X is
7126 // -- for each non-static data member of X that is of class type (or array
7127 // thereof), the constructor selected to copy/move that member is
7130 // C++11 [class.copy]p12, C++11 [class.copy]p25:
7131 // A [default constructor or destructor] is trivial if
7132 // -- for all of the non-static data members of its class that are of class
7133 // type (or array thereof), each such class has a trivial [default
7134 // constructor or destructor]
7135 if (!checkTrivialClassMembers(*this, RD, CSM, ConstArg, Diagnose))
7138 // C++11 [class.dtor]p5:
7139 // A destructor is trivial if [...]
7140 // -- the destructor is not virtual
7141 if (CSM == CXXDestructor && MD->isVirtual()) {
7143 Diag(MD->getLocation(), diag::note_nontrivial_virtual_dtor) << RD;
7147 // C++11 [class.ctor]p5, C++11 [class.copy]p12, C++11 [class.copy]p25:
7148 // A [special member] for class X is trivial if [...]
7149 // -- class X has no virtual functions and no virtual base classes
7150 if (CSM != CXXDestructor && MD->getParent()->isDynamicClass()) {
7154 if (RD->getNumVBases()) {
7155 // Check for virtual bases. We already know that the corresponding
7156 // member in all bases is trivial, so vbases must all be direct.
7157 CXXBaseSpecifier &BS = *RD->vbases_begin();
7158 assert(BS.isVirtual());
7159 Diag(BS.getLocStart(), diag::note_nontrivial_has_virtual) << RD << 1;
7163 // Must have a virtual method.
7164 for (const auto *MI : RD->methods()) {
7165 if (MI->isVirtual()) {
7166 SourceLocation MLoc = MI->getLocStart();
7167 Diag(MLoc, diag::note_nontrivial_has_virtual) << RD << 0;
7172 llvm_unreachable("dynamic class with no vbases and no virtual functions");
7175 // Looks like it's trivial!
7180 struct FindHiddenVirtualMethod {
7182 CXXMethodDecl *Method;
7183 llvm::SmallPtrSet<const CXXMethodDecl *, 8> OverridenAndUsingBaseMethods;
7184 SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
7187 /// Check whether any most overriden method from MD in Methods
7188 static bool CheckMostOverridenMethods(
7189 const CXXMethodDecl *MD,
7190 const llvm::SmallPtrSetImpl<const CXXMethodDecl *> &Methods) {
7191 if (MD->size_overridden_methods() == 0)
7192 return Methods.count(MD->getCanonicalDecl());
7193 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
7194 E = MD->end_overridden_methods();
7196 if (CheckMostOverridenMethods(*I, Methods))
7202 /// Member lookup function that determines whether a given C++
7203 /// method overloads virtual methods in a base class without overriding any,
7204 /// to be used with CXXRecordDecl::lookupInBases().
7205 bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
7206 RecordDecl *BaseRecord =
7207 Specifier->getType()->getAs<RecordType>()->getDecl();
7209 DeclarationName Name = Method->getDeclName();
7210 assert(Name.getNameKind() == DeclarationName::Identifier);
7212 bool foundSameNameMethod = false;
7213 SmallVector<CXXMethodDecl *, 8> overloadedMethods;
7214 for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty();
7215 Path.Decls = Path.Decls.slice(1)) {
7216 NamedDecl *D = Path.Decls.front();
7217 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
7218 MD = MD->getCanonicalDecl();
7219 foundSameNameMethod = true;
7220 // Interested only in hidden virtual methods.
7221 if (!MD->isVirtual())
7223 // If the method we are checking overrides a method from its base
7224 // don't warn about the other overloaded methods. Clang deviates from
7225 // GCC by only diagnosing overloads of inherited virtual functions that
7226 // do not override any other virtual functions in the base. GCC's
7227 // -Woverloaded-virtual diagnoses any derived function hiding a virtual
7228 // function from a base class. These cases may be better served by a
7229 // warning (not specific to virtual functions) on call sites when the
7230 // call would select a different function from the base class, were it
7232 // See FIXME in test/SemaCXX/warn-overload-virtual.cpp for an example.
7233 if (!S->IsOverload(Method, MD, false))
7235 // Collect the overload only if its hidden.
7236 if (!CheckMostOverridenMethods(MD, OverridenAndUsingBaseMethods))
7237 overloadedMethods.push_back(MD);
7241 if (foundSameNameMethod)
7242 OverloadedMethods.append(overloadedMethods.begin(),
7243 overloadedMethods.end());
7244 return foundSameNameMethod;
7247 } // end anonymous namespace
7249 /// \brief Add the most overriden methods from MD to Methods
7250 static void AddMostOverridenMethods(const CXXMethodDecl *MD,
7251 llvm::SmallPtrSetImpl<const CXXMethodDecl *>& Methods) {
7252 if (MD->size_overridden_methods() == 0)
7253 Methods.insert(MD->getCanonicalDecl());
7254 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
7255 E = MD->end_overridden_methods();
7257 AddMostOverridenMethods(*I, Methods);
7260 /// \brief Check if a method overloads virtual methods in a base class without
7262 void Sema::FindHiddenVirtualMethods(CXXMethodDecl *MD,
7263 SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods) {
7264 if (!MD->getDeclName().isIdentifier())
7267 CXXBasePaths Paths(/*FindAmbiguities=*/true, // true to look in all bases.
7268 /*bool RecordPaths=*/false,
7269 /*bool DetectVirtual=*/false);
7270 FindHiddenVirtualMethod FHVM;
7274 // Keep the base methods that were overriden or introduced in the subclass
7275 // by 'using' in a set. A base method not in this set is hidden.
7276 CXXRecordDecl *DC = MD->getParent();
7277 DeclContext::lookup_result R = DC->lookup(MD->getDeclName());
7278 for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E; ++I) {
7280 if (UsingShadowDecl *shad = dyn_cast<UsingShadowDecl>(*I))
7281 ND = shad->getTargetDecl();
7282 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ND))
7283 AddMostOverridenMethods(MD, FHVM.OverridenAndUsingBaseMethods);
7286 if (DC->lookupInBases(FHVM, Paths))
7287 OverloadedMethods = FHVM.OverloadedMethods;
7290 void Sema::NoteHiddenVirtualMethods(CXXMethodDecl *MD,
7291 SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods) {
7292 for (unsigned i = 0, e = OverloadedMethods.size(); i != e; ++i) {
7293 CXXMethodDecl *overloadedMD = OverloadedMethods[i];
7294 PartialDiagnostic PD = PDiag(
7295 diag::note_hidden_overloaded_virtual_declared_here) << overloadedMD;
7296 HandleFunctionTypeMismatch(PD, MD->getType(), overloadedMD->getType());
7297 Diag(overloadedMD->getLocation(), PD);
7301 /// \brief Diagnose methods which overload virtual methods in a base class
7302 /// without overriding any.
7303 void Sema::DiagnoseHiddenVirtualMethods(CXXMethodDecl *MD) {
7304 if (MD->isInvalidDecl())
7307 if (Diags.isIgnored(diag::warn_overloaded_virtual, MD->getLocation()))
7310 SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
7311 FindHiddenVirtualMethods(MD, OverloadedMethods);
7312 if (!OverloadedMethods.empty()) {
7313 Diag(MD->getLocation(), diag::warn_overloaded_virtual)
7314 << MD << (OverloadedMethods.size() > 1);
7316 NoteHiddenVirtualMethods(MD, OverloadedMethods);
7320 void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc,
7322 SourceLocation LBrac,
7323 SourceLocation RBrac,
7324 AttributeList *AttrList) {
7328 AdjustDeclIfTemplate(TagDecl);
7330 for (const AttributeList* l = AttrList; l; l = l->getNext()) {
7331 if (l->getKind() != AttributeList::AT_Visibility)
7334 Diag(l->getLoc(), diag::warn_attribute_after_definition_ignored) <<
7338 ActOnFields(S, RLoc, TagDecl, llvm::makeArrayRef(
7339 // strict aliasing violation!
7340 reinterpret_cast<Decl**>(FieldCollector->getCurFields()),
7341 FieldCollector->getCurNumFields()), LBrac, RBrac, AttrList);
7343 CheckCompletedCXXClass(
7344 dyn_cast_or_null<CXXRecordDecl>(TagDecl));
7347 /// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared
7348 /// special functions, such as the default constructor, copy
7349 /// constructor, or destructor, to the given C++ class (C++
7350 /// [special]p1). This routine can only be executed just before the
7351 /// definition of the class is complete.
7352 void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) {
7353 if (ClassDecl->needsImplicitDefaultConstructor()) {
7354 ++ASTContext::NumImplicitDefaultConstructors;
7356 if (ClassDecl->hasInheritedConstructor())
7357 DeclareImplicitDefaultConstructor(ClassDecl);
7360 if (ClassDecl->needsImplicitCopyConstructor()) {
7361 ++ASTContext::NumImplicitCopyConstructors;
7363 // If the properties or semantics of the copy constructor couldn't be
7364 // determined while the class was being declared, force a declaration
7366 if (ClassDecl->needsOverloadResolutionForCopyConstructor() ||
7367 ClassDecl->hasInheritedConstructor())
7368 DeclareImplicitCopyConstructor(ClassDecl);
7369 // For the MS ABI we need to know whether the copy ctor is deleted. A
7370 // prerequisite for deleting the implicit copy ctor is that the class has a
7371 // move ctor or move assignment that is either user-declared or whose
7372 // semantics are inherited from a subobject. FIXME: We should provide a more
7373 // direct way for CodeGen to ask whether the constructor was deleted.
7374 else if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
7375 (ClassDecl->hasUserDeclaredMoveConstructor() ||
7376 ClassDecl->needsOverloadResolutionForMoveConstructor() ||
7377 ClassDecl->hasUserDeclaredMoveAssignment() ||
7378 ClassDecl->needsOverloadResolutionForMoveAssignment()))
7379 DeclareImplicitCopyConstructor(ClassDecl);
7382 if (getLangOpts().CPlusPlus11 && ClassDecl->needsImplicitMoveConstructor()) {
7383 ++ASTContext::NumImplicitMoveConstructors;
7385 if (ClassDecl->needsOverloadResolutionForMoveConstructor() ||
7386 ClassDecl->hasInheritedConstructor())
7387 DeclareImplicitMoveConstructor(ClassDecl);
7390 if (ClassDecl->needsImplicitCopyAssignment()) {
7391 ++ASTContext::NumImplicitCopyAssignmentOperators;
7393 // If we have a dynamic class, then the copy assignment operator may be
7394 // virtual, so we have to declare it immediately. This ensures that, e.g.,
7395 // it shows up in the right place in the vtable and that we diagnose
7396 // problems with the implicit exception specification.
7397 if (ClassDecl->isDynamicClass() ||
7398 ClassDecl->needsOverloadResolutionForCopyAssignment() ||
7399 ClassDecl->hasInheritedAssignment())
7400 DeclareImplicitCopyAssignment(ClassDecl);
7403 if (getLangOpts().CPlusPlus11 && ClassDecl->needsImplicitMoveAssignment()) {
7404 ++ASTContext::NumImplicitMoveAssignmentOperators;
7406 // Likewise for the move assignment operator.
7407 if (ClassDecl->isDynamicClass() ||
7408 ClassDecl->needsOverloadResolutionForMoveAssignment() ||
7409 ClassDecl->hasInheritedAssignment())
7410 DeclareImplicitMoveAssignment(ClassDecl);
7413 if (ClassDecl->needsImplicitDestructor()) {
7414 ++ASTContext::NumImplicitDestructors;
7416 // If we have a dynamic class, then the destructor may be virtual, so we
7417 // have to declare the destructor immediately. This ensures that, e.g., it
7418 // shows up in the right place in the vtable and that we diagnose problems
7419 // with the implicit exception specification.
7420 if (ClassDecl->isDynamicClass() ||
7421 ClassDecl->needsOverloadResolutionForDestructor())
7422 DeclareImplicitDestructor(ClassDecl);
7426 unsigned Sema::ActOnReenterTemplateScope(Scope *S, Decl *D) {
7430 // The order of template parameters is not important here. All names
7431 // get added to the same scope.
7432 SmallVector<TemplateParameterList *, 4> ParameterLists;
7434 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
7435 D = TD->getTemplatedDecl();
7437 if (auto *PSD = dyn_cast<ClassTemplatePartialSpecializationDecl>(D))
7438 ParameterLists.push_back(PSD->getTemplateParameters());
7440 if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D)) {
7441 for (unsigned i = 0; i < DD->getNumTemplateParameterLists(); ++i)
7442 ParameterLists.push_back(DD->getTemplateParameterList(i));
7444 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
7445 if (FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate())
7446 ParameterLists.push_back(FTD->getTemplateParameters());
7450 if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
7451 for (unsigned i = 0; i < TD->getNumTemplateParameterLists(); ++i)
7452 ParameterLists.push_back(TD->getTemplateParameterList(i));
7454 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) {
7455 if (ClassTemplateDecl *CTD = RD->getDescribedClassTemplate())
7456 ParameterLists.push_back(CTD->getTemplateParameters());
7461 for (TemplateParameterList *Params : ParameterLists) {
7462 if (Params->size() > 0)
7463 // Ignore explicit specializations; they don't contribute to the template
7466 for (NamedDecl *Param : *Params) {
7467 if (Param->getDeclName()) {
7469 IdResolver.AddDecl(Param);
7477 void Sema::ActOnStartDelayedMemberDeclarations(Scope *S, Decl *RecordD) {
7478 if (!RecordD) return;
7479 AdjustDeclIfTemplate(RecordD);
7480 CXXRecordDecl *Record = cast<CXXRecordDecl>(RecordD);
7481 PushDeclContext(S, Record);
7484 void Sema::ActOnFinishDelayedMemberDeclarations(Scope *S, Decl *RecordD) {
7485 if (!RecordD) return;
7489 /// This is used to implement the constant expression evaluation part of the
7490 /// attribute enable_if extension. There is nothing in standard C++ which would
7491 /// require reentering parameters.
7492 void Sema::ActOnReenterCXXMethodParameter(Scope *S, ParmVarDecl *Param) {
7497 if (Param->getDeclName())
7498 IdResolver.AddDecl(Param);
7501 /// ActOnStartDelayedCXXMethodDeclaration - We have completed
7502 /// parsing a top-level (non-nested) C++ class, and we are now
7503 /// parsing those parts of the given Method declaration that could
7504 /// not be parsed earlier (C++ [class.mem]p2), such as default
7505 /// arguments. This action should enter the scope of the given
7506 /// Method declaration as if we had just parsed the qualified method
7507 /// name. However, it should not bring the parameters into scope;
7508 /// that will be performed by ActOnDelayedCXXMethodParameter.
7509 void Sema::ActOnStartDelayedCXXMethodDeclaration(Scope *S, Decl *MethodD) {
7512 /// ActOnDelayedCXXMethodParameter - We've already started a delayed
7513 /// C++ method declaration. We're (re-)introducing the given
7514 /// function parameter into scope for use in parsing later parts of
7515 /// the method declaration. For example, we could see an
7516 /// ActOnParamDefaultArgument event for this parameter.
7517 void Sema::ActOnDelayedCXXMethodParameter(Scope *S, Decl *ParamD) {
7521 ParmVarDecl *Param = cast<ParmVarDecl>(ParamD);
7523 // If this parameter has an unparsed default argument, clear it out
7524 // to make way for the parsed default argument.
7525 if (Param->hasUnparsedDefaultArg())
7526 Param->setDefaultArg(nullptr);
7529 if (Param->getDeclName())
7530 IdResolver.AddDecl(Param);
7533 /// ActOnFinishDelayedCXXMethodDeclaration - We have finished
7534 /// processing the delayed method declaration for Method. The method
7535 /// declaration is now considered finished. There may be a separate
7536 /// ActOnStartOfFunctionDef action later (not necessarily
7537 /// immediately!) for this method, if it was also defined inside the
7539 void Sema::ActOnFinishDelayedCXXMethodDeclaration(Scope *S, Decl *MethodD) {
7543 AdjustDeclIfTemplate(MethodD);
7545 FunctionDecl *Method = cast<FunctionDecl>(MethodD);
7547 // Now that we have our default arguments, check the constructor
7548 // again. It could produce additional diagnostics or affect whether
7549 // the class has implicitly-declared destructors, among other
7551 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Method))
7552 CheckConstructor(Constructor);
7554 // Check the default arguments, which we may have added.
7555 if (!Method->isInvalidDecl())
7556 CheckCXXDefaultArguments(Method);
7559 /// CheckConstructorDeclarator - Called by ActOnDeclarator to check
7560 /// the well-formedness of the constructor declarator @p D with type @p
7561 /// R. If there are any errors in the declarator, this routine will
7562 /// emit diagnostics and set the invalid bit to true. In any case, the type
7563 /// will be updated to reflect a well-formed type for the constructor and
7565 QualType Sema::CheckConstructorDeclarator(Declarator &D, QualType R,
7567 bool isVirtual = D.getDeclSpec().isVirtualSpecified();
7569 // C++ [class.ctor]p3:
7570 // A constructor shall not be virtual (10.3) or static (9.4). A
7571 // constructor can be invoked for a const, volatile or const
7572 // volatile object. A constructor shall not be declared const,
7573 // volatile, or const volatile (9.3.2).
7575 if (!D.isInvalidType())
7576 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be)
7577 << "virtual" << SourceRange(D.getDeclSpec().getVirtualSpecLoc())
7578 << SourceRange(D.getIdentifierLoc());
7581 if (SC == SC_Static) {
7582 if (!D.isInvalidType())
7583 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be)
7584 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
7585 << SourceRange(D.getIdentifierLoc());
7590 if (unsigned TypeQuals = D.getDeclSpec().getTypeQualifiers()) {
7591 diagnoseIgnoredQualifiers(
7592 diag::err_constructor_return_type, TypeQuals, SourceLocation(),
7593 D.getDeclSpec().getConstSpecLoc(), D.getDeclSpec().getVolatileSpecLoc(),
7594 D.getDeclSpec().getRestrictSpecLoc(),
7595 D.getDeclSpec().getAtomicSpecLoc());
7599 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
7600 if (FTI.TypeQuals != 0) {
7601 if (FTI.TypeQuals & Qualifiers::Const)
7602 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor)
7603 << "const" << SourceRange(D.getIdentifierLoc());
7604 if (FTI.TypeQuals & Qualifiers::Volatile)
7605 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor)
7606 << "volatile" << SourceRange(D.getIdentifierLoc());
7607 if (FTI.TypeQuals & Qualifiers::Restrict)
7608 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor)
7609 << "restrict" << SourceRange(D.getIdentifierLoc());
7613 // C++0x [class.ctor]p4:
7614 // A constructor shall not be declared with a ref-qualifier.
7615 if (FTI.hasRefQualifier()) {
7616 Diag(FTI.getRefQualifierLoc(), diag::err_ref_qualifier_constructor)
7617 << FTI.RefQualifierIsLValueRef
7618 << FixItHint::CreateRemoval(FTI.getRefQualifierLoc());
7622 // Rebuild the function type "R" without any type qualifiers (in
7623 // case any of the errors above fired) and with "void" as the
7624 // return type, since constructors don't have return types.
7625 const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
7626 if (Proto->getReturnType() == Context.VoidTy && !D.isInvalidType())
7629 FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
7631 EPI.RefQualifier = RQ_None;
7633 return Context.getFunctionType(Context.VoidTy, Proto->getParamTypes(), EPI);
7636 /// CheckConstructor - Checks a fully-formed constructor for
7637 /// well-formedness, issuing any diagnostics required. Returns true if
7638 /// the constructor declarator is invalid.
7639 void Sema::CheckConstructor(CXXConstructorDecl *Constructor) {
7640 CXXRecordDecl *ClassDecl
7641 = dyn_cast<CXXRecordDecl>(Constructor->getDeclContext());
7643 return Constructor->setInvalidDecl();
7645 // C++ [class.copy]p3:
7646 // A declaration of a constructor for a class X is ill-formed if
7647 // its first parameter is of type (optionally cv-qualified) X and
7648 // either there are no other parameters or else all other
7649 // parameters have default arguments.
7650 if (!Constructor->isInvalidDecl() &&
7651 ((Constructor->getNumParams() == 1) ||
7652 (Constructor->getNumParams() > 1 &&
7653 Constructor->getParamDecl(1)->hasDefaultArg())) &&
7654 Constructor->getTemplateSpecializationKind()
7655 != TSK_ImplicitInstantiation) {
7656 QualType ParamType = Constructor->getParamDecl(0)->getType();
7657 QualType ClassTy = Context.getTagDeclType(ClassDecl);
7658 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) {
7659 SourceLocation ParamLoc = Constructor->getParamDecl(0)->getLocation();
7660 const char *ConstRef
7661 = Constructor->getParamDecl(0)->getIdentifier() ? "const &"
7663 Diag(ParamLoc, diag::err_constructor_byvalue_arg)
7664 << FixItHint::CreateInsertion(ParamLoc, ConstRef);
7666 // FIXME: Rather that making the constructor invalid, we should endeavor
7668 Constructor->setInvalidDecl();
7673 /// CheckDestructor - Checks a fully-formed destructor definition for
7674 /// well-formedness, issuing any diagnostics required. Returns true
7676 bool Sema::CheckDestructor(CXXDestructorDecl *Destructor) {
7677 CXXRecordDecl *RD = Destructor->getParent();
7679 if (!Destructor->getOperatorDelete() && Destructor->isVirtual()) {
7682 if (!Destructor->isImplicit())
7683 Loc = Destructor->getLocation();
7685 Loc = RD->getLocation();
7687 // If we have a virtual destructor, look up the deallocation function
7688 if (FunctionDecl *OperatorDelete =
7689 FindDeallocationFunctionForDestructor(Loc, RD)) {
7690 MarkFunctionReferenced(Loc, OperatorDelete);
7691 Destructor->setOperatorDelete(OperatorDelete);
7698 /// CheckDestructorDeclarator - Called by ActOnDeclarator to check
7699 /// the well-formednes of the destructor declarator @p D with type @p
7700 /// R. If there are any errors in the declarator, this routine will
7701 /// emit diagnostics and set the declarator to invalid. Even if this happens,
7702 /// will be updated to reflect a well-formed type for the destructor and
7704 QualType Sema::CheckDestructorDeclarator(Declarator &D, QualType R,
7706 // C++ [class.dtor]p1:
7707 // [...] A typedef-name that names a class is a class-name
7708 // (7.1.3); however, a typedef-name that names a class shall not
7709 // be used as the identifier in the declarator for a destructor
7711 QualType DeclaratorType = GetTypeFromParser(D.getName().DestructorName);
7712 if (const TypedefType *TT = DeclaratorType->getAs<TypedefType>())
7713 Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name)
7714 << DeclaratorType << isa<TypeAliasDecl>(TT->getDecl());
7715 else if (const TemplateSpecializationType *TST =
7716 DeclaratorType->getAs<TemplateSpecializationType>())
7717 if (TST->isTypeAlias())
7718 Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name)
7719 << DeclaratorType << 1;
7721 // C++ [class.dtor]p2:
7722 // A destructor is used to destroy objects of its class type. A
7723 // destructor takes no parameters, and no return type can be
7724 // specified for it (not even void). The address of a destructor
7725 // shall not be taken. A destructor shall not be static. A
7726 // destructor can be invoked for a const, volatile or const
7727 // volatile object. A destructor shall not be declared const,
7728 // volatile or const volatile (9.3.2).
7729 if (SC == SC_Static) {
7730 if (!D.isInvalidType())
7731 Diag(D.getIdentifierLoc(), diag::err_destructor_cannot_be)
7732 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
7733 << SourceRange(D.getIdentifierLoc())
7734 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
7738 if (!D.isInvalidType()) {
7739 // Destructors don't have return types, but the parser will
7740 // happily parse something like:
7746 // The return type will be eliminated later.
7747 if (D.getDeclSpec().hasTypeSpecifier())
7748 Diag(D.getIdentifierLoc(), diag::err_destructor_return_type)
7749 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
7750 << SourceRange(D.getIdentifierLoc());
7751 else if (unsigned TypeQuals = D.getDeclSpec().getTypeQualifiers()) {
7752 diagnoseIgnoredQualifiers(diag::err_destructor_return_type, TypeQuals,
7754 D.getDeclSpec().getConstSpecLoc(),
7755 D.getDeclSpec().getVolatileSpecLoc(),
7756 D.getDeclSpec().getRestrictSpecLoc(),
7757 D.getDeclSpec().getAtomicSpecLoc());
7762 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
7763 if (FTI.TypeQuals != 0 && !D.isInvalidType()) {
7764 if (FTI.TypeQuals & Qualifiers::Const)
7765 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor)
7766 << "const" << SourceRange(D.getIdentifierLoc());
7767 if (FTI.TypeQuals & Qualifiers::Volatile)
7768 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor)
7769 << "volatile" << SourceRange(D.getIdentifierLoc());
7770 if (FTI.TypeQuals & Qualifiers::Restrict)
7771 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor)
7772 << "restrict" << SourceRange(D.getIdentifierLoc());
7776 // C++0x [class.dtor]p2:
7777 // A destructor shall not be declared with a ref-qualifier.
7778 if (FTI.hasRefQualifier()) {
7779 Diag(FTI.getRefQualifierLoc(), diag::err_ref_qualifier_destructor)
7780 << FTI.RefQualifierIsLValueRef
7781 << FixItHint::CreateRemoval(FTI.getRefQualifierLoc());
7785 // Make sure we don't have any parameters.
7786 if (FTIHasNonVoidParameters(FTI)) {
7787 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params);
7789 // Delete the parameters.
7794 // Make sure the destructor isn't variadic.
7795 if (FTI.isVariadic) {
7796 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic);
7800 // Rebuild the function type "R" without any type qualifiers or
7801 // parameters (in case any of the errors above fired) and with
7802 // "void" as the return type, since destructors don't have return
7804 if (!D.isInvalidType())
7807 const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
7808 FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
7809 EPI.Variadic = false;
7811 EPI.RefQualifier = RQ_None;
7812 return Context.getFunctionType(Context.VoidTy, None, EPI);
7815 static void extendLeft(SourceRange &R, SourceRange Before) {
7816 if (Before.isInvalid())
7818 R.setBegin(Before.getBegin());
7819 if (R.getEnd().isInvalid())
7820 R.setEnd(Before.getEnd());
7823 static void extendRight(SourceRange &R, SourceRange After) {
7824 if (After.isInvalid())
7826 if (R.getBegin().isInvalid())
7827 R.setBegin(After.getBegin());
7828 R.setEnd(After.getEnd());
7831 /// CheckConversionDeclarator - Called by ActOnDeclarator to check the
7832 /// well-formednes of the conversion function declarator @p D with
7833 /// type @p R. If there are any errors in the declarator, this routine
7834 /// will emit diagnostics and return true. Otherwise, it will return
7835 /// false. Either way, the type @p R will be updated to reflect a
7836 /// well-formed type for the conversion operator.
7837 void Sema::CheckConversionDeclarator(Declarator &D, QualType &R,
7839 // C++ [class.conv.fct]p1:
7840 // Neither parameter types nor return type can be specified. The
7841 // type of a conversion function (8.3.5) is "function taking no
7842 // parameter returning conversion-type-id."
7843 if (SC == SC_Static) {
7844 if (!D.isInvalidType())
7845 Diag(D.getIdentifierLoc(), diag::err_conv_function_not_member)
7846 << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
7847 << D.getName().getSourceRange();
7852 TypeSourceInfo *ConvTSI = nullptr;
7854 GetTypeFromParser(D.getName().ConversionFunctionId, &ConvTSI);
7856 if (D.getDeclSpec().hasTypeSpecifier() && !D.isInvalidType()) {
7857 // Conversion functions don't have return types, but the parser will
7858 // happily parse something like:
7861 // float operator bool();
7864 // The return type will be changed later anyway.
7865 Diag(D.getIdentifierLoc(), diag::err_conv_function_return_type)
7866 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
7867 << SourceRange(D.getIdentifierLoc());
7871 const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
7873 // Make sure we don't have any parameters.
7874 if (Proto->getNumParams() > 0) {
7875 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params);
7877 // Delete the parameters.
7878 D.getFunctionTypeInfo().freeParams();
7880 } else if (Proto->isVariadic()) {
7881 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic);
7885 // Diagnose "&operator bool()" and other such nonsense. This
7886 // is actually a gcc extension which we don't support.
7887 if (Proto->getReturnType() != ConvType) {
7888 bool NeedsTypedef = false;
7889 SourceRange Before, After;
7891 // Walk the chunks and extract information on them for our diagnostic.
7892 bool PastFunctionChunk = false;
7893 for (auto &Chunk : D.type_objects()) {
7894 switch (Chunk.Kind) {
7895 case DeclaratorChunk::Function:
7896 if (!PastFunctionChunk) {
7897 if (Chunk.Fun.HasTrailingReturnType) {
7898 TypeSourceInfo *TRT = nullptr;
7899 GetTypeFromParser(Chunk.Fun.getTrailingReturnType(), &TRT);
7900 if (TRT) extendRight(After, TRT->getTypeLoc().getSourceRange());
7902 PastFunctionChunk = true;
7906 case DeclaratorChunk::Array:
7907 NeedsTypedef = true;
7908 extendRight(After, Chunk.getSourceRange());
7911 case DeclaratorChunk::Pointer:
7912 case DeclaratorChunk::BlockPointer:
7913 case DeclaratorChunk::Reference:
7914 case DeclaratorChunk::MemberPointer:
7915 case DeclaratorChunk::Pipe:
7916 extendLeft(Before, Chunk.getSourceRange());
7919 case DeclaratorChunk::Paren:
7920 extendLeft(Before, Chunk.Loc);
7921 extendRight(After, Chunk.EndLoc);
7926 SourceLocation Loc = Before.isValid() ? Before.getBegin() :
7927 After.isValid() ? After.getBegin() :
7928 D.getIdentifierLoc();
7929 auto &&DB = Diag(Loc, diag::err_conv_function_with_complex_decl);
7930 DB << Before << After;
7932 if (!NeedsTypedef) {
7933 DB << /*don't need a typedef*/0;
7935 // If we can provide a correct fix-it hint, do so.
7936 if (After.isInvalid() && ConvTSI) {
7937 SourceLocation InsertLoc =
7938 getLocForEndOfToken(ConvTSI->getTypeLoc().getLocEnd());
7939 DB << FixItHint::CreateInsertion(InsertLoc, " ")
7940 << FixItHint::CreateInsertionFromRange(
7941 InsertLoc, CharSourceRange::getTokenRange(Before))
7942 << FixItHint::CreateRemoval(Before);
7944 } else if (!Proto->getReturnType()->isDependentType()) {
7945 DB << /*typedef*/1 << Proto->getReturnType();
7946 } else if (getLangOpts().CPlusPlus11) {
7947 DB << /*alias template*/2 << Proto->getReturnType();
7949 DB << /*might not be fixable*/3;
7952 // Recover by incorporating the other type chunks into the result type.
7953 // Note, this does *not* change the name of the function. This is compatible
7954 // with the GCC extension:
7955 // struct S { &operator int(); } s;
7956 // int &r = s.operator int(); // ok in GCC
7957 // S::operator int&() {} // error in GCC, function name is 'operator int'.
7958 ConvType = Proto->getReturnType();
7961 // C++ [class.conv.fct]p4:
7962 // The conversion-type-id shall not represent a function type nor
7964 if (ConvType->isArrayType()) {
7965 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array);
7966 ConvType = Context.getPointerType(ConvType);
7968 } else if (ConvType->isFunctionType()) {
7969 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function);
7970 ConvType = Context.getPointerType(ConvType);
7974 // Rebuild the function type "R" without any parameters (in case any
7975 // of the errors above fired) and with the conversion type as the
7977 if (D.isInvalidType())
7978 R = Context.getFunctionType(ConvType, None, Proto->getExtProtoInfo());
7980 // C++0x explicit conversion operators.
7981 if (D.getDeclSpec().isExplicitSpecified())
7982 Diag(D.getDeclSpec().getExplicitSpecLoc(),
7983 getLangOpts().CPlusPlus11 ?
7984 diag::warn_cxx98_compat_explicit_conversion_functions :
7985 diag::ext_explicit_conversion_functions)
7986 << SourceRange(D.getDeclSpec().getExplicitSpecLoc());
7989 /// ActOnConversionDeclarator - Called by ActOnDeclarator to complete
7990 /// the declaration of the given C++ conversion function. This routine
7991 /// is responsible for recording the conversion function in the C++
7992 /// class, if possible.
7993 Decl *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) {
7994 assert(Conversion && "Expected to receive a conversion function declaration");
7996 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Conversion->getDeclContext());
7998 // Make sure we aren't redeclaring the conversion function.
7999 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType());
8001 // C++ [class.conv.fct]p1:
8002 // [...] A conversion function is never used to convert a
8003 // (possibly cv-qualified) object to the (possibly cv-qualified)
8004 // same object type (or a reference to it), to a (possibly
8005 // cv-qualified) base class of that type (or a reference to it),
8006 // or to (possibly cv-qualified) void.
8007 // FIXME: Suppress this warning if the conversion function ends up being a
8008 // virtual function that overrides a virtual function in a base class.
8010 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
8011 if (const ReferenceType *ConvTypeRef = ConvType->getAs<ReferenceType>())
8012 ConvType = ConvTypeRef->getPointeeType();
8013 if (Conversion->getTemplateSpecializationKind() != TSK_Undeclared &&
8014 Conversion->getTemplateSpecializationKind() != TSK_ExplicitSpecialization)
8015 /* Suppress diagnostics for instantiations. */;
8016 else if (ConvType->isRecordType()) {
8017 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType();
8018 if (ConvType == ClassType)
8019 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used)
8021 else if (IsDerivedFrom(Conversion->getLocation(), ClassType, ConvType))
8022 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used)
8023 << ClassType << ConvType;
8024 } else if (ConvType->isVoidType()) {
8025 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used)
8026 << ClassType << ConvType;
8029 if (FunctionTemplateDecl *ConversionTemplate
8030 = Conversion->getDescribedFunctionTemplate())
8031 return ConversionTemplate;
8036 //===----------------------------------------------------------------------===//
8037 // Namespace Handling
8038 //===----------------------------------------------------------------------===//
8040 /// \brief Diagnose a mismatch in 'inline' qualifiers when a namespace is
8042 static void DiagnoseNamespaceInlineMismatch(Sema &S, SourceLocation KeywordLoc,
8044 IdentifierInfo *II, bool *IsInline,
8045 NamespaceDecl *PrevNS) {
8046 assert(*IsInline != PrevNS->isInline());
8048 // HACK: Work around a bug in libstdc++4.6's <atomic>, where
8049 // std::__atomic[0,1,2] are defined as non-inline namespaces, then reopened as
8050 // inline namespaces, with the intention of bringing names into namespace std.
8052 // We support this just well enough to get that case working; this is not
8053 // sufficient to support reopening namespaces as inline in general.
8054 if (*IsInline && II && II->getName().startswith("__atomic") &&
8055 S.getSourceManager().isInSystemHeader(Loc)) {
8056 // Mark all prior declarations of the namespace as inline.
8057 for (NamespaceDecl *NS = PrevNS->getMostRecentDecl(); NS;
8058 NS = NS->getPreviousDecl())
8059 NS->setInline(*IsInline);
8060 // Patch up the lookup table for the containing namespace. This isn't really
8061 // correct, but it's good enough for this particular case.
8062 for (auto *I : PrevNS->decls())
8063 if (auto *ND = dyn_cast<NamedDecl>(I))
8064 PrevNS->getParent()->makeDeclVisibleInContext(ND);
8068 if (PrevNS->isInline())
8069 // The user probably just forgot the 'inline', so suggest that it
8071 S.Diag(Loc, diag::warn_inline_namespace_reopened_noninline)
8072 << FixItHint::CreateInsertion(KeywordLoc, "inline ");
8074 S.Diag(Loc, diag::err_inline_namespace_mismatch);
8076 S.Diag(PrevNS->getLocation(), diag::note_previous_definition);
8077 *IsInline = PrevNS->isInline();
8080 /// ActOnStartNamespaceDef - This is called at the start of a namespace
8082 Decl *Sema::ActOnStartNamespaceDef(Scope *NamespcScope,
8083 SourceLocation InlineLoc,
8084 SourceLocation NamespaceLoc,
8085 SourceLocation IdentLoc,
8087 SourceLocation LBrace,
8088 AttributeList *AttrList,
8089 UsingDirectiveDecl *&UD) {
8090 SourceLocation StartLoc = InlineLoc.isValid() ? InlineLoc : NamespaceLoc;
8091 // For anonymous namespace, take the location of the left brace.
8092 SourceLocation Loc = II ? IdentLoc : LBrace;
8093 bool IsInline = InlineLoc.isValid();
8094 bool IsInvalid = false;
8096 bool AddToKnown = false;
8097 Scope *DeclRegionScope = NamespcScope->getParent();
8099 NamespaceDecl *PrevNS = nullptr;
8101 // C++ [namespace.def]p2:
8102 // The identifier in an original-namespace-definition shall not
8103 // have been previously defined in the declarative region in
8104 // which the original-namespace-definition appears. The
8105 // identifier in an original-namespace-definition is the name of
8106 // the namespace. Subsequently in that declarative region, it is
8107 // treated as an original-namespace-name.
8109 // Since namespace names are unique in their scope, and we don't
8110 // look through using directives, just look for any ordinary names
8111 // as if by qualified name lookup.
8112 LookupResult R(*this, II, IdentLoc, LookupOrdinaryName, ForRedeclaration);
8113 LookupQualifiedName(R, CurContext->getRedeclContext());
8114 NamedDecl *PrevDecl =
8115 R.isSingleResult() ? R.getRepresentativeDecl() : nullptr;
8116 PrevNS = dyn_cast_or_null<NamespaceDecl>(PrevDecl);
8119 // This is an extended namespace definition.
8120 if (IsInline != PrevNS->isInline())
8121 DiagnoseNamespaceInlineMismatch(*this, NamespaceLoc, Loc, II,
8123 } else if (PrevDecl) {
8124 // This is an invalid name redefinition.
8125 Diag(Loc, diag::err_redefinition_different_kind)
8127 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
8129 // Continue on to push Namespc as current DeclContext and return it.
8130 } else if (II->isStr("std") &&
8131 CurContext->getRedeclContext()->isTranslationUnit()) {
8132 // This is the first "real" definition of the namespace "std", so update
8133 // our cache of the "std" namespace to point at this definition.
8134 PrevNS = getStdNamespace();
8136 AddToKnown = !IsInline;
8138 // We've seen this namespace for the first time.
8139 AddToKnown = !IsInline;
8142 // Anonymous namespaces.
8144 // Determine whether the parent already has an anonymous namespace.
8145 DeclContext *Parent = CurContext->getRedeclContext();
8146 if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(Parent)) {
8147 PrevNS = TU->getAnonymousNamespace();
8149 NamespaceDecl *ND = cast<NamespaceDecl>(Parent);
8150 PrevNS = ND->getAnonymousNamespace();
8153 if (PrevNS && IsInline != PrevNS->isInline())
8154 DiagnoseNamespaceInlineMismatch(*this, NamespaceLoc, NamespaceLoc, II,
8158 NamespaceDecl *Namespc = NamespaceDecl::Create(Context, CurContext, IsInline,
8159 StartLoc, Loc, II, PrevNS);
8161 Namespc->setInvalidDecl();
8163 ProcessDeclAttributeList(DeclRegionScope, Namespc, AttrList);
8165 // FIXME: Should we be merging attributes?
8166 if (const VisibilityAttr *Attr = Namespc->getAttr<VisibilityAttr>())
8167 PushNamespaceVisibilityAttr(Attr, Loc);
8170 StdNamespace = Namespc;
8172 KnownNamespaces[Namespc] = false;
8175 PushOnScopeChains(Namespc, DeclRegionScope);
8177 // Link the anonymous namespace into its parent.
8178 DeclContext *Parent = CurContext->getRedeclContext();
8179 if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(Parent)) {
8180 TU->setAnonymousNamespace(Namespc);
8182 cast<NamespaceDecl>(Parent)->setAnonymousNamespace(Namespc);
8185 CurContext->addDecl(Namespc);
8187 // C++ [namespace.unnamed]p1. An unnamed-namespace-definition
8188 // behaves as if it were replaced by
8189 // namespace unique { /* empty body */ }
8190 // using namespace unique;
8191 // namespace unique { namespace-body }
8192 // where all occurrences of 'unique' in a translation unit are
8193 // replaced by the same identifier and this identifier differs
8194 // from all other identifiers in the entire program.
8196 // We just create the namespace with an empty name and then add an
8197 // implicit using declaration, just like the standard suggests.
8199 // CodeGen enforces the "universally unique" aspect by giving all
8200 // declarations semantically contained within an anonymous
8201 // namespace internal linkage.
8204 UD = UsingDirectiveDecl::Create(Context, Parent,
8205 /* 'using' */ LBrace,
8206 /* 'namespace' */ SourceLocation(),
8207 /* qualifier */ NestedNameSpecifierLoc(),
8208 /* identifier */ SourceLocation(),
8210 /* Ancestor */ Parent);
8212 Parent->addDecl(UD);
8216 ActOnDocumentableDecl(Namespc);
8218 // Although we could have an invalid decl (i.e. the namespace name is a
8219 // redefinition), push it as current DeclContext and try to continue parsing.
8220 // FIXME: We should be able to push Namespc here, so that the each DeclContext
8221 // for the namespace has the declarations that showed up in that particular
8222 // namespace definition.
8223 PushDeclContext(NamespcScope, Namespc);
8227 /// getNamespaceDecl - Returns the namespace a decl represents. If the decl
8228 /// is a namespace alias, returns the namespace it points to.
8229 static inline NamespaceDecl *getNamespaceDecl(NamedDecl *D) {
8230 if (NamespaceAliasDecl *AD = dyn_cast_or_null<NamespaceAliasDecl>(D))
8231 return AD->getNamespace();
8232 return dyn_cast_or_null<NamespaceDecl>(D);
8235 /// ActOnFinishNamespaceDef - This callback is called after a namespace is
8236 /// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef.
8237 void Sema::ActOnFinishNamespaceDef(Decl *Dcl, SourceLocation RBrace) {
8238 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl);
8239 assert(Namespc && "Invalid parameter, expected NamespaceDecl");
8240 Namespc->setRBraceLoc(RBrace);
8242 if (Namespc->hasAttr<VisibilityAttr>())
8243 PopPragmaVisibility(true, RBrace);
8246 CXXRecordDecl *Sema::getStdBadAlloc() const {
8247 return cast_or_null<CXXRecordDecl>(
8248 StdBadAlloc.get(Context.getExternalSource()));
8251 EnumDecl *Sema::getStdAlignValT() const {
8252 return cast_or_null<EnumDecl>(StdAlignValT.get(Context.getExternalSource()));
8255 NamespaceDecl *Sema::getStdNamespace() const {
8256 return cast_or_null<NamespaceDecl>(
8257 StdNamespace.get(Context.getExternalSource()));
8260 NamespaceDecl *Sema::lookupStdExperimentalNamespace() {
8261 if (!StdExperimentalNamespaceCache) {
8262 if (auto Std = getStdNamespace()) {
8263 LookupResult Result(*this, &PP.getIdentifierTable().get("experimental"),
8264 SourceLocation(), LookupNamespaceName);
8265 if (!LookupQualifiedName(Result, Std) ||
8266 !(StdExperimentalNamespaceCache =
8267 Result.getAsSingle<NamespaceDecl>()))
8268 Result.suppressDiagnostics();
8271 return StdExperimentalNamespaceCache;
8274 /// \brief Retrieve the special "std" namespace, which may require us to
8275 /// implicitly define the namespace.
8276 NamespaceDecl *Sema::getOrCreateStdNamespace() {
8277 if (!StdNamespace) {
8278 // The "std" namespace has not yet been defined, so build one implicitly.
8279 StdNamespace = NamespaceDecl::Create(Context,
8280 Context.getTranslationUnitDecl(),
8282 SourceLocation(), SourceLocation(),
8283 &PP.getIdentifierTable().get("std"),
8284 /*PrevDecl=*/nullptr);
8285 getStdNamespace()->setImplicit(true);
8288 return getStdNamespace();
8291 bool Sema::isStdInitializerList(QualType Ty, QualType *Element) {
8292 assert(getLangOpts().CPlusPlus &&
8293 "Looking for std::initializer_list outside of C++.");
8295 // We're looking for implicit instantiations of
8296 // template <typename E> class std::initializer_list.
8298 if (!StdNamespace) // If we haven't seen namespace std yet, this can't be it.
8301 ClassTemplateDecl *Template = nullptr;
8302 const TemplateArgument *Arguments = nullptr;
8304 if (const RecordType *RT = Ty->getAs<RecordType>()) {
8306 ClassTemplateSpecializationDecl *Specialization =
8307 dyn_cast<ClassTemplateSpecializationDecl>(RT->getDecl());
8308 if (!Specialization)
8311 Template = Specialization->getSpecializedTemplate();
8312 Arguments = Specialization->getTemplateArgs().data();
8313 } else if (const TemplateSpecializationType *TST =
8314 Ty->getAs<TemplateSpecializationType>()) {
8315 Template = dyn_cast_or_null<ClassTemplateDecl>(
8316 TST->getTemplateName().getAsTemplateDecl());
8317 Arguments = TST->getArgs();
8322 if (!StdInitializerList) {
8323 // Haven't recognized std::initializer_list yet, maybe this is it.
8324 CXXRecordDecl *TemplateClass = Template->getTemplatedDecl();
8325 if (TemplateClass->getIdentifier() !=
8326 &PP.getIdentifierTable().get("initializer_list") ||
8327 !getStdNamespace()->InEnclosingNamespaceSetOf(
8328 TemplateClass->getDeclContext()))
8330 // This is a template called std::initializer_list, but is it the right
8332 TemplateParameterList *Params = Template->getTemplateParameters();
8333 if (Params->getMinRequiredArguments() != 1)
8335 if (!isa<TemplateTypeParmDecl>(Params->getParam(0)))
8338 // It's the right template.
8339 StdInitializerList = Template;
8342 if (Template->getCanonicalDecl() != StdInitializerList->getCanonicalDecl())
8345 // This is an instance of std::initializer_list. Find the argument type.
8347 *Element = Arguments[0].getAsType();
8351 static ClassTemplateDecl *LookupStdInitializerList(Sema &S, SourceLocation Loc){
8352 NamespaceDecl *Std = S.getStdNamespace();
8354 S.Diag(Loc, diag::err_implied_std_initializer_list_not_found);
8358 LookupResult Result(S, &S.PP.getIdentifierTable().get("initializer_list"),
8359 Loc, Sema::LookupOrdinaryName);
8360 if (!S.LookupQualifiedName(Result, Std)) {
8361 S.Diag(Loc, diag::err_implied_std_initializer_list_not_found);
8364 ClassTemplateDecl *Template = Result.getAsSingle<ClassTemplateDecl>();
8366 Result.suppressDiagnostics();
8367 // We found something weird. Complain about the first thing we found.
8368 NamedDecl *Found = *Result.begin();
8369 S.Diag(Found->getLocation(), diag::err_malformed_std_initializer_list);
8373 // We found some template called std::initializer_list. Now verify that it's
8375 TemplateParameterList *Params = Template->getTemplateParameters();
8376 if (Params->getMinRequiredArguments() != 1 ||
8377 !isa<TemplateTypeParmDecl>(Params->getParam(0))) {
8378 S.Diag(Template->getLocation(), diag::err_malformed_std_initializer_list);
8385 QualType Sema::BuildStdInitializerList(QualType Element, SourceLocation Loc) {
8386 if (!StdInitializerList) {
8387 StdInitializerList = LookupStdInitializerList(*this, Loc);
8388 if (!StdInitializerList)
8392 TemplateArgumentListInfo Args(Loc, Loc);
8393 Args.addArgument(TemplateArgumentLoc(TemplateArgument(Element),
8394 Context.getTrivialTypeSourceInfo(Element,
8396 return Context.getCanonicalType(
8397 CheckTemplateIdType(TemplateName(StdInitializerList), Loc, Args));
8400 bool Sema::isInitListConstructor(const CXXConstructorDecl* Ctor) {
8401 // C++ [dcl.init.list]p2:
8402 // A constructor is an initializer-list constructor if its first parameter
8403 // is of type std::initializer_list<E> or reference to possibly cv-qualified
8404 // std::initializer_list<E> for some type E, and either there are no other
8405 // parameters or else all other parameters have default arguments.
8406 if (Ctor->getNumParams() < 1 ||
8407 (Ctor->getNumParams() > 1 && !Ctor->getParamDecl(1)->hasDefaultArg()))
8410 QualType ArgType = Ctor->getParamDecl(0)->getType();
8411 if (const ReferenceType *RT = ArgType->getAs<ReferenceType>())
8412 ArgType = RT->getPointeeType().getUnqualifiedType();
8414 return isStdInitializerList(ArgType, nullptr);
8417 /// \brief Determine whether a using statement is in a context where it will be
8418 /// apply in all contexts.
8419 static bool IsUsingDirectiveInToplevelContext(DeclContext *CurContext) {
8420 switch (CurContext->getDeclKind()) {
8421 case Decl::TranslationUnit:
8423 case Decl::LinkageSpec:
8424 return IsUsingDirectiveInToplevelContext(CurContext->getParent());
8432 // Callback to only accept typo corrections that are namespaces.
8433 class NamespaceValidatorCCC : public CorrectionCandidateCallback {
8435 bool ValidateCandidate(const TypoCorrection &candidate) override {
8436 if (NamedDecl *ND = candidate.getCorrectionDecl())
8437 return isa<NamespaceDecl>(ND) || isa<NamespaceAliasDecl>(ND);
8444 static bool TryNamespaceTypoCorrection(Sema &S, LookupResult &R, Scope *Sc,
8446 SourceLocation IdentLoc,
8447 IdentifierInfo *Ident) {
8449 if (TypoCorrection Corrected =
8450 S.CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), Sc, &SS,
8451 llvm::make_unique<NamespaceValidatorCCC>(),
8452 Sema::CTK_ErrorRecovery)) {
8453 if (DeclContext *DC = S.computeDeclContext(SS, false)) {
8454 std::string CorrectedStr(Corrected.getAsString(S.getLangOpts()));
8455 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
8456 Ident->getName().equals(CorrectedStr);
8457 S.diagnoseTypo(Corrected,
8458 S.PDiag(diag::err_using_directive_member_suggest)
8459 << Ident << DC << DroppedSpecifier << SS.getRange(),
8460 S.PDiag(diag::note_namespace_defined_here));
8462 S.diagnoseTypo(Corrected,
8463 S.PDiag(diag::err_using_directive_suggest) << Ident,
8464 S.PDiag(diag::note_namespace_defined_here));
8466 R.addDecl(Corrected.getFoundDecl());
8472 Decl *Sema::ActOnUsingDirective(Scope *S,
8473 SourceLocation UsingLoc,
8474 SourceLocation NamespcLoc,
8476 SourceLocation IdentLoc,
8477 IdentifierInfo *NamespcName,
8478 AttributeList *AttrList) {
8479 assert(!SS.isInvalid() && "Invalid CXXScopeSpec.");
8480 assert(NamespcName && "Invalid NamespcName.");
8481 assert(IdentLoc.isValid() && "Invalid NamespceName location.");
8483 // This can only happen along a recovery path.
8484 while (S->isTemplateParamScope())
8486 assert(S->getFlags() & Scope::DeclScope && "Invalid Scope.");
8488 UsingDirectiveDecl *UDir = nullptr;
8489 NestedNameSpecifier *Qualifier = nullptr;
8491 Qualifier = SS.getScopeRep();
8493 // Lookup namespace name.
8494 LookupResult R(*this, NamespcName, IdentLoc, LookupNamespaceName);
8495 LookupParsedName(R, S, &SS);
8496 if (R.isAmbiguous())
8501 // Allow "using namespace std;" or "using namespace ::std;" even if
8502 // "std" hasn't been defined yet, for GCC compatibility.
8503 if ((!Qualifier || Qualifier->getKind() == NestedNameSpecifier::Global) &&
8504 NamespcName->isStr("std")) {
8505 Diag(IdentLoc, diag::ext_using_undefined_std);
8506 R.addDecl(getOrCreateStdNamespace());
8509 // Otherwise, attempt typo correction.
8510 else TryNamespaceTypoCorrection(*this, R, S, SS, IdentLoc, NamespcName);
8514 NamedDecl *Named = R.getRepresentativeDecl();
8515 NamespaceDecl *NS = R.getAsSingle<NamespaceDecl>();
8516 assert(NS && "expected namespace decl");
8518 // The use of a nested name specifier may trigger deprecation warnings.
8519 DiagnoseUseOfDecl(Named, IdentLoc);
8521 // C++ [namespace.udir]p1:
8522 // A using-directive specifies that the names in the nominated
8523 // namespace can be used in the scope in which the
8524 // using-directive appears after the using-directive. During
8525 // unqualified name lookup (3.4.1), the names appear as if they
8526 // were declared in the nearest enclosing namespace which
8527 // contains both the using-directive and the nominated
8528 // namespace. [Note: in this context, "contains" means "contains
8529 // directly or indirectly". ]
8531 // Find enclosing context containing both using-directive and
8532 // nominated namespace.
8533 DeclContext *CommonAncestor = cast<DeclContext>(NS);
8534 while (CommonAncestor && !CommonAncestor->Encloses(CurContext))
8535 CommonAncestor = CommonAncestor->getParent();
8537 UDir = UsingDirectiveDecl::Create(Context, CurContext, UsingLoc, NamespcLoc,
8538 SS.getWithLocInContext(Context),
8539 IdentLoc, Named, CommonAncestor);
8541 if (IsUsingDirectiveInToplevelContext(CurContext) &&
8542 !SourceMgr.isInMainFile(SourceMgr.getExpansionLoc(IdentLoc))) {
8543 Diag(IdentLoc, diag::warn_using_directive_in_header);
8546 PushUsingDirective(S, UDir);
8548 Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange();
8552 ProcessDeclAttributeList(S, UDir, AttrList);
8557 void Sema::PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir) {
8558 // If the scope has an associated entity and the using directive is at
8559 // namespace or translation unit scope, add the UsingDirectiveDecl into
8560 // its lookup structure so qualified name lookup can find it.
8561 DeclContext *Ctx = S->getEntity();
8562 if (Ctx && !Ctx->isFunctionOrMethod())
8565 // Otherwise, it is at block scope. The using-directives will affect lookup
8566 // only to the end of the scope.
8567 S->PushUsingDirective(UDir);
8571 Decl *Sema::ActOnUsingDeclaration(Scope *S,
8573 SourceLocation UsingLoc,
8574 SourceLocation TypenameLoc,
8576 UnqualifiedId &Name,
8577 SourceLocation EllipsisLoc,
8578 AttributeList *AttrList) {
8579 assert(S->getFlags() & Scope::DeclScope && "Invalid Scope.");
8582 Diag(Name.getLocStart(), diag::err_using_requires_qualname);
8586 switch (Name.getKind()) {
8587 case UnqualifiedId::IK_ImplicitSelfParam:
8588 case UnqualifiedId::IK_Identifier:
8589 case UnqualifiedId::IK_OperatorFunctionId:
8590 case UnqualifiedId::IK_LiteralOperatorId:
8591 case UnqualifiedId::IK_ConversionFunctionId:
8594 case UnqualifiedId::IK_ConstructorName:
8595 case UnqualifiedId::IK_ConstructorTemplateId:
8596 // C++11 inheriting constructors.
8597 Diag(Name.getLocStart(),
8598 getLangOpts().CPlusPlus11 ?
8599 diag::warn_cxx98_compat_using_decl_constructor :
8600 diag::err_using_decl_constructor)
8603 if (getLangOpts().CPlusPlus11) break;
8607 case UnqualifiedId::IK_DestructorName:
8608 Diag(Name.getLocStart(), diag::err_using_decl_destructor)
8612 case UnqualifiedId::IK_TemplateId:
8613 Diag(Name.getLocStart(), diag::err_using_decl_template_id)
8614 << SourceRange(Name.TemplateId->LAngleLoc, Name.TemplateId->RAngleLoc);
8618 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
8619 DeclarationName TargetName = TargetNameInfo.getName();
8623 // Warn about access declarations.
8624 if (UsingLoc.isInvalid()) {
8625 Diag(Name.getLocStart(),
8626 getLangOpts().CPlusPlus11 ? diag::err_access_decl
8627 : diag::warn_access_decl_deprecated)
8628 << FixItHint::CreateInsertion(SS.getRange().getBegin(), "using ");
8631 if (EllipsisLoc.isInvalid()) {
8632 if (DiagnoseUnexpandedParameterPack(SS, UPPC_UsingDeclaration) ||
8633 DiagnoseUnexpandedParameterPack(TargetNameInfo, UPPC_UsingDeclaration))
8636 if (!SS.getScopeRep()->containsUnexpandedParameterPack() &&
8637 !TargetNameInfo.containsUnexpandedParameterPack()) {
8638 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
8639 << SourceRange(SS.getBeginLoc(), TargetNameInfo.getEndLoc());
8640 EllipsisLoc = SourceLocation();
8645 BuildUsingDeclaration(S, AS, UsingLoc, TypenameLoc.isValid(), TypenameLoc,
8646 SS, TargetNameInfo, EllipsisLoc, AttrList,
8647 /*IsInstantiation*/false);
8649 PushOnScopeChains(UD, S, /*AddToContext*/ false);
8654 /// \brief Determine whether a using declaration considers the given
8655 /// declarations as "equivalent", e.g., if they are redeclarations of
8656 /// the same entity or are both typedefs of the same type.
8658 IsEquivalentForUsingDecl(ASTContext &Context, NamedDecl *D1, NamedDecl *D2) {
8659 if (D1->getCanonicalDecl() == D2->getCanonicalDecl())
8662 if (TypedefNameDecl *TD1 = dyn_cast<TypedefNameDecl>(D1))
8663 if (TypedefNameDecl *TD2 = dyn_cast<TypedefNameDecl>(D2))
8664 return Context.hasSameType(TD1->getUnderlyingType(),
8665 TD2->getUnderlyingType());
8671 /// Determines whether to create a using shadow decl for a particular
8672 /// decl, given the set of decls existing prior to this using lookup.
8673 bool Sema::CheckUsingShadowDecl(UsingDecl *Using, NamedDecl *Orig,
8674 const LookupResult &Previous,
8675 UsingShadowDecl *&PrevShadow) {
8676 // Diagnose finding a decl which is not from a base class of the
8677 // current class. We do this now because there are cases where this
8678 // function will silently decide not to build a shadow decl, which
8679 // will pre-empt further diagnostics.
8681 // We don't need to do this in C++11 because we do the check once on
8684 // FIXME: diagnose the following if we care enough:
8685 // struct A { int foo; };
8686 // struct B : A { using A::foo; };
8687 // template <class T> struct C : A {};
8688 // template <class T> struct D : C<T> { using B::foo; } // <---
8689 // This is invalid (during instantiation) in C++03 because B::foo
8690 // resolves to the using decl in B, which is not a base class of D<T>.
8691 // We can't diagnose it immediately because C<T> is an unknown
8692 // specialization. The UsingShadowDecl in D<T> then points directly
8693 // to A::foo, which will look well-formed when we instantiate.
8694 // The right solution is to not collapse the shadow-decl chain.
8695 if (!getLangOpts().CPlusPlus11 && CurContext->isRecord()) {
8696 DeclContext *OrigDC = Orig->getDeclContext();
8698 // Handle enums and anonymous structs.
8699 if (isa<EnumDecl>(OrigDC)) OrigDC = OrigDC->getParent();
8700 CXXRecordDecl *OrigRec = cast<CXXRecordDecl>(OrigDC);
8701 while (OrigRec->isAnonymousStructOrUnion())
8702 OrigRec = cast<CXXRecordDecl>(OrigRec->getDeclContext());
8704 if (cast<CXXRecordDecl>(CurContext)->isProvablyNotDerivedFrom(OrigRec)) {
8705 if (OrigDC == CurContext) {
8706 Diag(Using->getLocation(),
8707 diag::err_using_decl_nested_name_specifier_is_current_class)
8708 << Using->getQualifierLoc().getSourceRange();
8709 Diag(Orig->getLocation(), diag::note_using_decl_target);
8710 Using->setInvalidDecl();
8714 Diag(Using->getQualifierLoc().getBeginLoc(),
8715 diag::err_using_decl_nested_name_specifier_is_not_base_class)
8716 << Using->getQualifier()
8717 << cast<CXXRecordDecl>(CurContext)
8718 << Using->getQualifierLoc().getSourceRange();
8719 Diag(Orig->getLocation(), diag::note_using_decl_target);
8720 Using->setInvalidDecl();
8725 if (Previous.empty()) return false;
8727 NamedDecl *Target = Orig;
8728 if (isa<UsingShadowDecl>(Target))
8729 Target = cast<UsingShadowDecl>(Target)->getTargetDecl();
8731 // If the target happens to be one of the previous declarations, we
8732 // don't have a conflict.
8734 // FIXME: but we might be increasing its access, in which case we
8735 // should redeclare it.
8736 NamedDecl *NonTag = nullptr, *Tag = nullptr;
8737 bool FoundEquivalentDecl = false;
8738 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
8740 NamedDecl *D = (*I)->getUnderlyingDecl();
8741 // We can have UsingDecls in our Previous results because we use the same
8742 // LookupResult for checking whether the UsingDecl itself is a valid
8744 if (isa<UsingDecl>(D) || isa<UsingPackDecl>(D))
8747 if (IsEquivalentForUsingDecl(Context, D, Target)) {
8748 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(*I))
8749 PrevShadow = Shadow;
8750 FoundEquivalentDecl = true;
8751 } else if (isEquivalentInternalLinkageDeclaration(D, Target)) {
8752 // We don't conflict with an existing using shadow decl of an equivalent
8753 // declaration, but we're not a redeclaration of it.
8754 FoundEquivalentDecl = true;
8758 (isa<TagDecl>(D) ? Tag : NonTag) = D;
8761 if (FoundEquivalentDecl)
8764 if (FunctionDecl *FD = Target->getAsFunction()) {
8765 NamedDecl *OldDecl = nullptr;
8766 switch (CheckOverload(nullptr, FD, Previous, OldDecl,
8767 /*IsForUsingDecl*/ true)) {
8771 case Ovl_NonFunction:
8772 Diag(Using->getLocation(), diag::err_using_decl_conflict);
8775 // We found a decl with the exact signature.
8777 // If we're in a record, we want to hide the target, so we
8778 // return true (without a diagnostic) to tell the caller not to
8779 // build a shadow decl.
8780 if (CurContext->isRecord())
8783 // If we're not in a record, this is an error.
8784 Diag(Using->getLocation(), diag::err_using_decl_conflict);
8788 Diag(Target->getLocation(), diag::note_using_decl_target);
8789 Diag(OldDecl->getLocation(), diag::note_using_decl_conflict);
8790 Using->setInvalidDecl();
8794 // Target is not a function.
8796 if (isa<TagDecl>(Target)) {
8797 // No conflict between a tag and a non-tag.
8798 if (!Tag) return false;
8800 Diag(Using->getLocation(), diag::err_using_decl_conflict);
8801 Diag(Target->getLocation(), diag::note_using_decl_target);
8802 Diag(Tag->getLocation(), diag::note_using_decl_conflict);
8803 Using->setInvalidDecl();
8807 // No conflict between a tag and a non-tag.
8808 if (!NonTag) return false;
8810 Diag(Using->getLocation(), diag::err_using_decl_conflict);
8811 Diag(Target->getLocation(), diag::note_using_decl_target);
8812 Diag(NonTag->getLocation(), diag::note_using_decl_conflict);
8813 Using->setInvalidDecl();
8817 /// Determine whether a direct base class is a virtual base class.
8818 static bool isVirtualDirectBase(CXXRecordDecl *Derived, CXXRecordDecl *Base) {
8819 if (!Derived->getNumVBases())
8821 for (auto &B : Derived->bases())
8822 if (B.getType()->getAsCXXRecordDecl() == Base)
8823 return B.isVirtual();
8824 llvm_unreachable("not a direct base class");
8827 /// Builds a shadow declaration corresponding to a 'using' declaration.
8828 UsingShadowDecl *Sema::BuildUsingShadowDecl(Scope *S,
8831 UsingShadowDecl *PrevDecl) {
8832 // If we resolved to another shadow declaration, just coalesce them.
8833 NamedDecl *Target = Orig;
8834 if (isa<UsingShadowDecl>(Target)) {
8835 Target = cast<UsingShadowDecl>(Target)->getTargetDecl();
8836 assert(!isa<UsingShadowDecl>(Target) && "nested shadow declaration");
8839 NamedDecl *NonTemplateTarget = Target;
8840 if (auto *TargetTD = dyn_cast<TemplateDecl>(Target))
8841 NonTemplateTarget = TargetTD->getTemplatedDecl();
8843 UsingShadowDecl *Shadow;
8844 if (isa<CXXConstructorDecl>(NonTemplateTarget)) {
8845 bool IsVirtualBase =
8846 isVirtualDirectBase(cast<CXXRecordDecl>(CurContext),
8847 UD->getQualifier()->getAsRecordDecl());
8848 Shadow = ConstructorUsingShadowDecl::Create(
8849 Context, CurContext, UD->getLocation(), UD, Orig, IsVirtualBase);
8851 Shadow = UsingShadowDecl::Create(Context, CurContext, UD->getLocation(), UD,
8854 UD->addShadowDecl(Shadow);
8856 Shadow->setAccess(UD->getAccess());
8857 if (Orig->isInvalidDecl() || UD->isInvalidDecl())
8858 Shadow->setInvalidDecl();
8860 Shadow->setPreviousDecl(PrevDecl);
8863 PushOnScopeChains(Shadow, S);
8865 CurContext->addDecl(Shadow);
8871 /// Hides a using shadow declaration. This is required by the current
8872 /// using-decl implementation when a resolvable using declaration in a
8873 /// class is followed by a declaration which would hide or override
8874 /// one or more of the using decl's targets; for example:
8876 /// struct Base { void foo(int); };
8877 /// struct Derived : Base {
8878 /// using Base::foo;
8882 /// The governing language is C++03 [namespace.udecl]p12:
8884 /// When a using-declaration brings names from a base class into a
8885 /// derived class scope, member functions in the derived class
8886 /// override and/or hide member functions with the same name and
8887 /// parameter types in a base class (rather than conflicting).
8889 /// There are two ways to implement this:
8890 /// (1) optimistically create shadow decls when they're not hidden
8891 /// by existing declarations, or
8892 /// (2) don't create any shadow decls (or at least don't make them
8893 /// visible) until we've fully parsed/instantiated the class.
8894 /// The problem with (1) is that we might have to retroactively remove
8895 /// a shadow decl, which requires several O(n) operations because the
8896 /// decl structures are (very reasonably) not designed for removal.
8897 /// (2) avoids this but is very fiddly and phase-dependent.
8898 void Sema::HideUsingShadowDecl(Scope *S, UsingShadowDecl *Shadow) {
8899 if (Shadow->getDeclName().getNameKind() ==
8900 DeclarationName::CXXConversionFunctionName)
8901 cast<CXXRecordDecl>(Shadow->getDeclContext())->removeConversion(Shadow);
8903 // Remove it from the DeclContext...
8904 Shadow->getDeclContext()->removeDecl(Shadow);
8906 // ...and the scope, if applicable...
8908 S->RemoveDecl(Shadow);
8909 IdResolver.RemoveDecl(Shadow);
8912 // ...and the using decl.
8913 Shadow->getUsingDecl()->removeShadowDecl(Shadow);
8915 // TODO: complain somehow if Shadow was used. It shouldn't
8916 // be possible for this to happen, because...?
8919 /// Find the base specifier for a base class with the given type.
8920 static CXXBaseSpecifier *findDirectBaseWithType(CXXRecordDecl *Derived,
8921 QualType DesiredBase,
8922 bool &AnyDependentBases) {
8923 // Check whether the named type is a direct base class.
8924 CanQualType CanonicalDesiredBase = DesiredBase->getCanonicalTypeUnqualified();
8925 for (auto &Base : Derived->bases()) {
8926 CanQualType BaseType = Base.getType()->getCanonicalTypeUnqualified();
8927 if (CanonicalDesiredBase == BaseType)
8929 if (BaseType->isDependentType())
8930 AnyDependentBases = true;
8936 class UsingValidatorCCC : public CorrectionCandidateCallback {
8938 UsingValidatorCCC(bool HasTypenameKeyword, bool IsInstantiation,
8939 NestedNameSpecifier *NNS, CXXRecordDecl *RequireMemberOf)
8940 : HasTypenameKeyword(HasTypenameKeyword),
8941 IsInstantiation(IsInstantiation), OldNNS(NNS),
8942 RequireMemberOf(RequireMemberOf) {}
8944 bool ValidateCandidate(const TypoCorrection &Candidate) override {
8945 NamedDecl *ND = Candidate.getCorrectionDecl();
8947 // Keywords are not valid here.
8948 if (!ND || isa<NamespaceDecl>(ND))
8951 // Completely unqualified names are invalid for a 'using' declaration.
8952 if (Candidate.WillReplaceSpecifier() && !Candidate.getCorrectionSpecifier())
8955 // FIXME: Don't correct to a name that CheckUsingDeclRedeclaration would
8958 if (RequireMemberOf) {
8959 auto *FoundRecord = dyn_cast<CXXRecordDecl>(ND);
8960 if (FoundRecord && FoundRecord->isInjectedClassName()) {
8961 // No-one ever wants a using-declaration to name an injected-class-name
8962 // of a base class, unless they're declaring an inheriting constructor.
8963 ASTContext &Ctx = ND->getASTContext();
8964 if (!Ctx.getLangOpts().CPlusPlus11)
8966 QualType FoundType = Ctx.getRecordType(FoundRecord);
8968 // Check that the injected-class-name is named as a member of its own
8969 // type; we don't want to suggest 'using Derived::Base;', since that
8970 // means something else.
8971 NestedNameSpecifier *Specifier =
8972 Candidate.WillReplaceSpecifier()
8973 ? Candidate.getCorrectionSpecifier()
8975 if (!Specifier->getAsType() ||
8976 !Ctx.hasSameType(QualType(Specifier->getAsType(), 0), FoundType))
8979 // Check that this inheriting constructor declaration actually names a
8980 // direct base class of the current class.
8981 bool AnyDependentBases = false;
8982 if (!findDirectBaseWithType(RequireMemberOf,
8983 Ctx.getRecordType(FoundRecord),
8984 AnyDependentBases) &&
8988 auto *RD = dyn_cast<CXXRecordDecl>(ND->getDeclContext());
8989 if (!RD || RequireMemberOf->isProvablyNotDerivedFrom(RD))
8992 // FIXME: Check that the base class member is accessible?
8995 auto *FoundRecord = dyn_cast<CXXRecordDecl>(ND);
8996 if (FoundRecord && FoundRecord->isInjectedClassName())
9000 if (isa<TypeDecl>(ND))
9001 return HasTypenameKeyword || !IsInstantiation;
9003 return !HasTypenameKeyword;
9007 bool HasTypenameKeyword;
9008 bool IsInstantiation;
9009 NestedNameSpecifier *OldNNS;
9010 CXXRecordDecl *RequireMemberOf;
9012 } // end anonymous namespace
9014 /// Builds a using declaration.
9016 /// \param IsInstantiation - Whether this call arises from an
9017 /// instantiation of an unresolved using declaration. We treat
9018 /// the lookup differently for these declarations.
9019 NamedDecl *Sema::BuildUsingDeclaration(Scope *S, AccessSpecifier AS,
9020 SourceLocation UsingLoc,
9021 bool HasTypenameKeyword,
9022 SourceLocation TypenameLoc,
9024 DeclarationNameInfo NameInfo,
9025 SourceLocation EllipsisLoc,
9026 AttributeList *AttrList,
9027 bool IsInstantiation) {
9028 assert(!SS.isInvalid() && "Invalid CXXScopeSpec.");
9029 SourceLocation IdentLoc = NameInfo.getLoc();
9030 assert(IdentLoc.isValid() && "Invalid TargetName location.");
9032 // FIXME: We ignore attributes for now.
9034 // For an inheriting constructor declaration, the name of the using
9035 // declaration is the name of a constructor in this class, not in the
9037 DeclarationNameInfo UsingName = NameInfo;
9038 if (UsingName.getName().getNameKind() == DeclarationName::CXXConstructorName)
9039 if (auto *RD = dyn_cast<CXXRecordDecl>(CurContext))
9040 UsingName.setName(Context.DeclarationNames.getCXXConstructorName(
9041 Context.getCanonicalType(Context.getRecordType(RD))));
9043 // Do the redeclaration lookup in the current scope.
9044 LookupResult Previous(*this, UsingName, LookupUsingDeclName,
9046 Previous.setHideTags(false);
9048 LookupName(Previous, S);
9050 // It is really dumb that we have to do this.
9051 LookupResult::Filter F = Previous.makeFilter();
9052 while (F.hasNext()) {
9053 NamedDecl *D = F.next();
9054 if (!isDeclInScope(D, CurContext, S))
9056 // If we found a local extern declaration that's not ordinarily visible,
9057 // and this declaration is being added to a non-block scope, ignore it.
9058 // We're only checking for scope conflicts here, not also for violations
9059 // of the linkage rules.
9060 else if (!CurContext->isFunctionOrMethod() && D->isLocalExternDecl() &&
9061 !(D->getIdentifierNamespace() & Decl::IDNS_Ordinary))
9066 assert(IsInstantiation && "no scope in non-instantiation");
9067 if (CurContext->isRecord())
9068 LookupQualifiedName(Previous, CurContext);
9070 // No redeclaration check is needed here; in non-member contexts we
9071 // diagnosed all possible conflicts with other using-declarations when
9072 // building the template:
9074 // For a dependent non-type using declaration, the only valid case is
9075 // if we instantiate to a single enumerator. We check for conflicts
9076 // between shadow declarations we introduce, and we check in the template
9077 // definition for conflicts between a non-type using declaration and any
9078 // other declaration, which together covers all cases.
9080 // A dependent typename using declaration will never successfully
9081 // instantiate, since it will always name a class member, so we reject
9082 // that in the template definition.
9086 // Check for invalid redeclarations.
9087 if (CheckUsingDeclRedeclaration(UsingLoc, HasTypenameKeyword,
9088 SS, IdentLoc, Previous))
9091 // Check for bad qualifiers.
9092 if (CheckUsingDeclQualifier(UsingLoc, HasTypenameKeyword, SS, NameInfo,
9096 DeclContext *LookupContext = computeDeclContext(SS);
9098 NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
9099 if (!LookupContext || EllipsisLoc.isValid()) {
9100 if (HasTypenameKeyword) {
9101 // FIXME: not all declaration name kinds are legal here
9102 D = UnresolvedUsingTypenameDecl::Create(Context, CurContext,
9103 UsingLoc, TypenameLoc,
9105 IdentLoc, NameInfo.getName(),
9108 D = UnresolvedUsingValueDecl::Create(Context, CurContext, UsingLoc,
9109 QualifierLoc, NameInfo, EllipsisLoc);
9112 CurContext->addDecl(D);
9116 auto Build = [&](bool Invalid) {
9118 UsingDecl::Create(Context, CurContext, UsingLoc, QualifierLoc,
9119 UsingName, HasTypenameKeyword);
9121 CurContext->addDecl(UD);
9122 UD->setInvalidDecl(Invalid);
9125 auto BuildInvalid = [&]{ return Build(true); };
9126 auto BuildValid = [&]{ return Build(false); };
9128 if (RequireCompleteDeclContext(SS, LookupContext))
9129 return BuildInvalid();
9131 // Look up the target name.
9132 LookupResult R(*this, NameInfo, LookupOrdinaryName);
9134 // Unlike most lookups, we don't always want to hide tag
9135 // declarations: tag names are visible through the using declaration
9136 // even if hidden by ordinary names, *except* in a dependent context
9137 // where it's important for the sanity of two-phase lookup.
9138 if (!IsInstantiation)
9139 R.setHideTags(false);
9141 // For the purposes of this lookup, we have a base object type
9142 // equal to that of the current context.
9143 if (CurContext->isRecord()) {
9144 R.setBaseObjectType(
9145 Context.getTypeDeclType(cast<CXXRecordDecl>(CurContext)));
9148 LookupQualifiedName(R, LookupContext);
9150 // Try to correct typos if possible. If constructor name lookup finds no
9151 // results, that means the named class has no explicit constructors, and we
9152 // suppressed declaring implicit ones (probably because it's dependent or
9155 NameInfo.getName().getNameKind() != DeclarationName::CXXConstructorName) {
9156 // HACK: Work around a bug in libstdc++'s detection of ::gets. Sometimes
9157 // it will believe that glibc provides a ::gets in cases where it does not,
9158 // and will try to pull it into namespace std with a using-declaration.
9159 // Just ignore the using-declaration in that case.
9160 auto *II = NameInfo.getName().getAsIdentifierInfo();
9161 if (getLangOpts().CPlusPlus14 && II && II->isStr("gets") &&
9162 CurContext->isStdNamespace() &&
9163 isa<TranslationUnitDecl>(LookupContext) &&
9164 getSourceManager().isInSystemHeader(UsingLoc))
9166 if (TypoCorrection Corrected = CorrectTypo(
9167 R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
9168 llvm::make_unique<UsingValidatorCCC>(
9169 HasTypenameKeyword, IsInstantiation, SS.getScopeRep(),
9170 dyn_cast<CXXRecordDecl>(CurContext)),
9171 CTK_ErrorRecovery)) {
9172 // We reject any correction for which ND would be NULL.
9173 NamedDecl *ND = Corrected.getCorrectionDecl();
9175 // We reject candidates where DroppedSpecifier == true, hence the
9176 // literal '0' below.
9177 diagnoseTypo(Corrected, PDiag(diag::err_no_member_suggest)
9178 << NameInfo.getName() << LookupContext << 0
9181 // If we corrected to an inheriting constructor, handle it as one.
9182 auto *RD = dyn_cast<CXXRecordDecl>(ND);
9183 if (RD && RD->isInjectedClassName()) {
9184 // The parent of the injected class name is the class itself.
9185 RD = cast<CXXRecordDecl>(RD->getParent());
9187 // Fix up the information we'll use to build the using declaration.
9188 if (Corrected.WillReplaceSpecifier()) {
9189 NestedNameSpecifierLocBuilder Builder;
9190 Builder.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
9191 QualifierLoc.getSourceRange());
9192 QualifierLoc = Builder.getWithLocInContext(Context);
9195 // In this case, the name we introduce is the name of a derived class
9197 auto *CurClass = cast<CXXRecordDecl>(CurContext);
9198 UsingName.setName(Context.DeclarationNames.getCXXConstructorName(
9199 Context.getCanonicalType(Context.getRecordType(CurClass))));
9200 UsingName.setNamedTypeInfo(nullptr);
9201 for (auto *Ctor : LookupConstructors(RD))
9205 // FIXME: Pick up all the declarations if we found an overloaded
9207 UsingName.setName(ND->getDeclName());
9211 Diag(IdentLoc, diag::err_no_member)
9212 << NameInfo.getName() << LookupContext << SS.getRange();
9213 return BuildInvalid();
9217 if (R.isAmbiguous())
9218 return BuildInvalid();
9220 if (HasTypenameKeyword) {
9221 // If we asked for a typename and got a non-type decl, error out.
9222 if (!R.getAsSingle<TypeDecl>()) {
9223 Diag(IdentLoc, diag::err_using_typename_non_type);
9224 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
9225 Diag((*I)->getUnderlyingDecl()->getLocation(),
9226 diag::note_using_decl_target);
9227 return BuildInvalid();
9230 // If we asked for a non-typename and we got a type, error out,
9231 // but only if this is an instantiation of an unresolved using
9232 // decl. Otherwise just silently find the type name.
9233 if (IsInstantiation && R.getAsSingle<TypeDecl>()) {
9234 Diag(IdentLoc, diag::err_using_dependent_value_is_type);
9235 Diag(R.getFoundDecl()->getLocation(), diag::note_using_decl_target);
9236 return BuildInvalid();
9240 // C++14 [namespace.udecl]p6:
9241 // A using-declaration shall not name a namespace.
9242 if (R.getAsSingle<NamespaceDecl>()) {
9243 Diag(IdentLoc, diag::err_using_decl_can_not_refer_to_namespace)
9245 return BuildInvalid();
9248 // C++14 [namespace.udecl]p7:
9249 // A using-declaration shall not name a scoped enumerator.
9250 if (auto *ED = R.getAsSingle<EnumConstantDecl>()) {
9251 if (cast<EnumDecl>(ED->getDeclContext())->isScoped()) {
9252 Diag(IdentLoc, diag::err_using_decl_can_not_refer_to_scoped_enum)
9254 return BuildInvalid();
9258 UsingDecl *UD = BuildValid();
9260 // Some additional rules apply to inheriting constructors.
9261 if (UsingName.getName().getNameKind() ==
9262 DeclarationName::CXXConstructorName) {
9263 // Suppress access diagnostics; the access check is instead performed at the
9264 // point of use for an inheriting constructor.
9265 R.suppressDiagnostics();
9266 if (CheckInheritingConstructorUsingDecl(UD))
9270 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
9271 UsingShadowDecl *PrevDecl = nullptr;
9272 if (!CheckUsingShadowDecl(UD, *I, Previous, PrevDecl))
9273 BuildUsingShadowDecl(S, UD, *I, PrevDecl);
9279 NamedDecl *Sema::BuildUsingPackDecl(NamedDecl *InstantiatedFrom,
9280 ArrayRef<NamedDecl *> Expansions) {
9281 assert(isa<UnresolvedUsingValueDecl>(InstantiatedFrom) ||
9282 isa<UnresolvedUsingTypenameDecl>(InstantiatedFrom) ||
9283 isa<UsingPackDecl>(InstantiatedFrom));
9286 UsingPackDecl::Create(Context, CurContext, InstantiatedFrom, Expansions);
9287 UPD->setAccess(InstantiatedFrom->getAccess());
9288 CurContext->addDecl(UPD);
9292 /// Additional checks for a using declaration referring to a constructor name.
9293 bool Sema::CheckInheritingConstructorUsingDecl(UsingDecl *UD) {
9294 assert(!UD->hasTypename() && "expecting a constructor name");
9296 const Type *SourceType = UD->getQualifier()->getAsType();
9297 assert(SourceType &&
9298 "Using decl naming constructor doesn't have type in scope spec.");
9299 CXXRecordDecl *TargetClass = cast<CXXRecordDecl>(CurContext);
9301 // Check whether the named type is a direct base class.
9302 bool AnyDependentBases = false;
9303 auto *Base = findDirectBaseWithType(TargetClass, QualType(SourceType, 0),
9305 if (!Base && !AnyDependentBases) {
9306 Diag(UD->getUsingLoc(),
9307 diag::err_using_decl_constructor_not_in_direct_base)
9308 << UD->getNameInfo().getSourceRange()
9309 << QualType(SourceType, 0) << TargetClass;
9310 UD->setInvalidDecl();
9315 Base->setInheritConstructors();
9320 /// Checks that the given using declaration is not an invalid
9321 /// redeclaration. Note that this is checking only for the using decl
9322 /// itself, not for any ill-formedness among the UsingShadowDecls.
9323 bool Sema::CheckUsingDeclRedeclaration(SourceLocation UsingLoc,
9324 bool HasTypenameKeyword,
9325 const CXXScopeSpec &SS,
9326 SourceLocation NameLoc,
9327 const LookupResult &Prev) {
9328 NestedNameSpecifier *Qual = SS.getScopeRep();
9330 // C++03 [namespace.udecl]p8:
9331 // C++0x [namespace.udecl]p10:
9332 // A using-declaration is a declaration and can therefore be used
9333 // repeatedly where (and only where) multiple declarations are
9336 // That's in non-member contexts.
9337 if (!CurContext->getRedeclContext()->isRecord()) {
9338 // A dependent qualifier outside a class can only ever resolve to an
9339 // enumeration type. Therefore it conflicts with any other non-type
9340 // declaration in the same scope.
9341 // FIXME: How should we check for dependent type-type conflicts at block
9343 if (Qual->isDependent() && !HasTypenameKeyword) {
9344 for (auto *D : Prev) {
9345 if (!isa<TypeDecl>(D) && !isa<UsingDecl>(D) && !isa<UsingPackDecl>(D)) {
9346 bool OldCouldBeEnumerator =
9347 isa<UnresolvedUsingValueDecl>(D) || isa<EnumConstantDecl>(D);
9349 OldCouldBeEnumerator ? diag::err_redefinition
9350 : diag::err_redefinition_different_kind)
9351 << Prev.getLookupName();
9352 Diag(D->getLocation(), diag::note_previous_definition);
9360 for (LookupResult::iterator I = Prev.begin(), E = Prev.end(); I != E; ++I) {
9364 NestedNameSpecifier *DQual;
9365 if (UsingDecl *UD = dyn_cast<UsingDecl>(D)) {
9366 DTypename = UD->hasTypename();
9367 DQual = UD->getQualifier();
9368 } else if (UnresolvedUsingValueDecl *UD
9369 = dyn_cast<UnresolvedUsingValueDecl>(D)) {
9371 DQual = UD->getQualifier();
9372 } else if (UnresolvedUsingTypenameDecl *UD
9373 = dyn_cast<UnresolvedUsingTypenameDecl>(D)) {
9375 DQual = UD->getQualifier();
9378 // using decls differ if one says 'typename' and the other doesn't.
9379 // FIXME: non-dependent using decls?
9380 if (HasTypenameKeyword != DTypename) continue;
9382 // using decls differ if they name different scopes (but note that
9383 // template instantiation can cause this check to trigger when it
9384 // didn't before instantiation).
9385 if (Context.getCanonicalNestedNameSpecifier(Qual) !=
9386 Context.getCanonicalNestedNameSpecifier(DQual))
9389 Diag(NameLoc, diag::err_using_decl_redeclaration) << SS.getRange();
9390 Diag(D->getLocation(), diag::note_using_decl) << 1;
9398 /// Checks that the given nested-name qualifier used in a using decl
9399 /// in the current context is appropriately related to the current
9400 /// scope. If an error is found, diagnoses it and returns true.
9401 bool Sema::CheckUsingDeclQualifier(SourceLocation UsingLoc,
9403 const CXXScopeSpec &SS,
9404 const DeclarationNameInfo &NameInfo,
9405 SourceLocation NameLoc) {
9406 DeclContext *NamedContext = computeDeclContext(SS);
9408 if (!CurContext->isRecord()) {
9409 // C++03 [namespace.udecl]p3:
9410 // C++0x [namespace.udecl]p8:
9411 // A using-declaration for a class member shall be a member-declaration.
9413 // If we weren't able to compute a valid scope, it might validly be a
9414 // dependent class scope or a dependent enumeration unscoped scope. If
9415 // we have a 'typename' keyword, the scope must resolve to a class type.
9416 if ((HasTypename && !NamedContext) ||
9417 (NamedContext && NamedContext->getRedeclContext()->isRecord())) {
9418 auto *RD = NamedContext
9419 ? cast<CXXRecordDecl>(NamedContext->getRedeclContext())
9421 if (RD && RequireCompleteDeclContext(const_cast<CXXScopeSpec&>(SS), RD))
9424 Diag(NameLoc, diag::err_using_decl_can_not_refer_to_class_member)
9427 // If we have a complete, non-dependent source type, try to suggest a
9428 // way to get the same effect.
9432 // Find what this using-declaration was referring to.
9433 LookupResult R(*this, NameInfo, LookupOrdinaryName);
9434 R.setHideTags(false);
9435 R.suppressDiagnostics();
9436 LookupQualifiedName(R, RD);
9438 if (R.getAsSingle<TypeDecl>()) {
9439 if (getLangOpts().CPlusPlus11) {
9440 // Convert 'using X::Y;' to 'using Y = X::Y;'.
9441 Diag(SS.getBeginLoc(), diag::note_using_decl_class_member_workaround)
9442 << 0 // alias declaration
9443 << FixItHint::CreateInsertion(SS.getBeginLoc(),
9444 NameInfo.getName().getAsString() +
9447 // Convert 'using X::Y;' to 'typedef X::Y Y;'.
9448 SourceLocation InsertLoc =
9449 getLocForEndOfToken(NameInfo.getLocEnd());
9450 Diag(InsertLoc, diag::note_using_decl_class_member_workaround)
9451 << 1 // typedef declaration
9452 << FixItHint::CreateReplacement(UsingLoc, "typedef")
9453 << FixItHint::CreateInsertion(
9454 InsertLoc, " " + NameInfo.getName().getAsString());
9456 } else if (R.getAsSingle<VarDecl>()) {
9457 // Don't provide a fixit outside C++11 mode; we don't want to suggest
9458 // repeating the type of the static data member here.
9460 if (getLangOpts().CPlusPlus11) {
9461 // Convert 'using X::Y;' to 'auto &Y = X::Y;'.
9462 FixIt = FixItHint::CreateReplacement(
9463 UsingLoc, "auto &" + NameInfo.getName().getAsString() + " = ");
9466 Diag(UsingLoc, diag::note_using_decl_class_member_workaround)
9467 << 2 // reference declaration
9469 } else if (R.getAsSingle<EnumConstantDecl>()) {
9470 // Don't provide a fixit outside C++11 mode; we don't want to suggest
9471 // repeating the type of the enumeration here, and we can't do so if
9472 // the type is anonymous.
9474 if (getLangOpts().CPlusPlus11) {
9475 // Convert 'using X::Y;' to 'auto &Y = X::Y;'.
9476 FixIt = FixItHint::CreateReplacement(
9478 "constexpr auto " + NameInfo.getName().getAsString() + " = ");
9481 Diag(UsingLoc, diag::note_using_decl_class_member_workaround)
9482 << (getLangOpts().CPlusPlus11 ? 4 : 3) // const[expr] variable
9488 // Otherwise, this might be valid.
9492 // The current scope is a record.
9494 // If the named context is dependent, we can't decide much.
9495 if (!NamedContext) {
9496 // FIXME: in C++0x, we can diagnose if we can prove that the
9497 // nested-name-specifier does not refer to a base class, which is
9498 // still possible in some cases.
9500 // Otherwise we have to conservatively report that things might be
9505 if (!NamedContext->isRecord()) {
9506 // Ideally this would point at the last name in the specifier,
9507 // but we don't have that level of source info.
9508 Diag(SS.getRange().getBegin(),
9509 diag::err_using_decl_nested_name_specifier_is_not_class)
9510 << SS.getScopeRep() << SS.getRange();
9514 if (!NamedContext->isDependentContext() &&
9515 RequireCompleteDeclContext(const_cast<CXXScopeSpec&>(SS), NamedContext))
9518 if (getLangOpts().CPlusPlus11) {
9519 // C++11 [namespace.udecl]p3:
9520 // In a using-declaration used as a member-declaration, the
9521 // nested-name-specifier shall name a base class of the class
9524 if (cast<CXXRecordDecl>(CurContext)->isProvablyNotDerivedFrom(
9525 cast<CXXRecordDecl>(NamedContext))) {
9526 if (CurContext == NamedContext) {
9528 diag::err_using_decl_nested_name_specifier_is_current_class)
9533 if (!cast<CXXRecordDecl>(NamedContext)->isInvalidDecl()) {
9534 Diag(SS.getRange().getBegin(),
9535 diag::err_using_decl_nested_name_specifier_is_not_base_class)
9537 << cast<CXXRecordDecl>(CurContext)
9546 // C++03 [namespace.udecl]p4:
9547 // A using-declaration used as a member-declaration shall refer
9548 // to a member of a base class of the class being defined [etc.].
9550 // Salient point: SS doesn't have to name a base class as long as
9551 // lookup only finds members from base classes. Therefore we can
9552 // diagnose here only if we can prove that that can't happen,
9553 // i.e. if the class hierarchies provably don't intersect.
9555 // TODO: it would be nice if "definitely valid" results were cached
9556 // in the UsingDecl and UsingShadowDecl so that these checks didn't
9557 // need to be repeated.
9559 llvm::SmallPtrSet<const CXXRecordDecl *, 4> Bases;
9560 auto Collect = [&Bases](const CXXRecordDecl *Base) {
9565 // Collect all bases. Return false if we find a dependent base.
9566 if (!cast<CXXRecordDecl>(CurContext)->forallBases(Collect))
9569 // Returns true if the base is dependent or is one of the accumulated base
9571 auto IsNotBase = [&Bases](const CXXRecordDecl *Base) {
9572 return !Bases.count(Base);
9575 // Return false if the class has a dependent base or if it or one
9576 // of its bases is present in the base set of the current context.
9577 if (Bases.count(cast<CXXRecordDecl>(NamedContext)) ||
9578 !cast<CXXRecordDecl>(NamedContext)->forallBases(IsNotBase))
9581 Diag(SS.getRange().getBegin(),
9582 diag::err_using_decl_nested_name_specifier_is_not_base_class)
9584 << cast<CXXRecordDecl>(CurContext)
9590 Decl *Sema::ActOnAliasDeclaration(Scope *S,
9592 MultiTemplateParamsArg TemplateParamLists,
9593 SourceLocation UsingLoc,
9594 UnqualifiedId &Name,
9595 AttributeList *AttrList,
9597 Decl *DeclFromDeclSpec) {
9598 // Skip up to the relevant declaration scope.
9599 while (S->isTemplateParamScope())
9601 assert((S->getFlags() & Scope::DeclScope) &&
9602 "got alias-declaration outside of declaration scope");
9604 if (Type.isInvalid())
9607 bool Invalid = false;
9608 DeclarationNameInfo NameInfo = GetNameFromUnqualifiedId(Name);
9609 TypeSourceInfo *TInfo = nullptr;
9610 GetTypeFromParser(Type.get(), &TInfo);
9612 if (DiagnoseClassNameShadow(CurContext, NameInfo))
9615 if (DiagnoseUnexpandedParameterPack(Name.StartLocation, TInfo,
9616 UPPC_DeclarationType)) {
9618 TInfo = Context.getTrivialTypeSourceInfo(Context.IntTy,
9619 TInfo->getTypeLoc().getBeginLoc());
9622 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, ForRedeclaration);
9623 LookupName(Previous, S);
9625 // Warn about shadowing the name of a template parameter.
9626 if (Previous.isSingleResult() &&
9627 Previous.getFoundDecl()->isTemplateParameter()) {
9628 DiagnoseTemplateParameterShadow(Name.StartLocation,Previous.getFoundDecl());
9632 assert(Name.Kind == UnqualifiedId::IK_Identifier &&
9633 "name in alias declaration must be an identifier");
9634 TypeAliasDecl *NewTD = TypeAliasDecl::Create(Context, CurContext, UsingLoc,
9636 Name.Identifier, TInfo);
9638 NewTD->setAccess(AS);
9641 NewTD->setInvalidDecl();
9643 ProcessDeclAttributeList(S, NewTD, AttrList);
9645 CheckTypedefForVariablyModifiedType(S, NewTD);
9646 Invalid |= NewTD->isInvalidDecl();
9648 bool Redeclaration = false;
9651 if (TemplateParamLists.size()) {
9652 TypeAliasTemplateDecl *OldDecl = nullptr;
9653 TemplateParameterList *OldTemplateParams = nullptr;
9655 if (TemplateParamLists.size() != 1) {
9656 Diag(UsingLoc, diag::err_alias_template_extra_headers)
9657 << SourceRange(TemplateParamLists[1]->getTemplateLoc(),
9658 TemplateParamLists[TemplateParamLists.size()-1]->getRAngleLoc());
9660 TemplateParameterList *TemplateParams = TemplateParamLists[0];
9662 // Check that we can declare a template here.
9663 if (CheckTemplateDeclScope(S, TemplateParams))
9666 // Only consider previous declarations in the same scope.
9667 FilterLookupForScope(Previous, CurContext, S, /*ConsiderLinkage*/false,
9668 /*ExplicitInstantiationOrSpecialization*/false);
9669 if (!Previous.empty()) {
9670 Redeclaration = true;
9672 OldDecl = Previous.getAsSingle<TypeAliasTemplateDecl>();
9673 if (!OldDecl && !Invalid) {
9674 Diag(UsingLoc, diag::err_redefinition_different_kind)
9677 NamedDecl *OldD = Previous.getRepresentativeDecl();
9678 if (OldD->getLocation().isValid())
9679 Diag(OldD->getLocation(), diag::note_previous_definition);
9684 if (!Invalid && OldDecl && !OldDecl->isInvalidDecl()) {
9685 if (TemplateParameterListsAreEqual(TemplateParams,
9686 OldDecl->getTemplateParameters(),
9689 OldTemplateParams = OldDecl->getTemplateParameters();
9693 TypeAliasDecl *OldTD = OldDecl->getTemplatedDecl();
9695 !Context.hasSameType(OldTD->getUnderlyingType(),
9696 NewTD->getUnderlyingType())) {
9697 // FIXME: The C++0x standard does not clearly say this is ill-formed,
9698 // but we can't reasonably accept it.
9699 Diag(NewTD->getLocation(), diag::err_redefinition_different_typedef)
9700 << 2 << NewTD->getUnderlyingType() << OldTD->getUnderlyingType();
9701 if (OldTD->getLocation().isValid())
9702 Diag(OldTD->getLocation(), diag::note_previous_definition);
9708 // Merge any previous default template arguments into our parameters,
9709 // and check the parameter list.
9710 if (CheckTemplateParameterList(TemplateParams, OldTemplateParams,
9711 TPC_TypeAliasTemplate))
9714 TypeAliasTemplateDecl *NewDecl =
9715 TypeAliasTemplateDecl::Create(Context, CurContext, UsingLoc,
9716 Name.Identifier, TemplateParams,
9718 NewTD->setDescribedAliasTemplate(NewDecl);
9720 NewDecl->setAccess(AS);
9723 NewDecl->setInvalidDecl();
9725 NewDecl->setPreviousDecl(OldDecl);
9729 if (auto *TD = dyn_cast_or_null<TagDecl>(DeclFromDeclSpec)) {
9730 setTagNameForLinkagePurposes(TD, NewTD);
9731 handleTagNumbering(TD, S);
9733 ActOnTypedefNameDecl(S, CurContext, NewTD, Previous, Redeclaration);
9737 PushOnScopeChains(NewND, S);
9738 ActOnDocumentableDecl(NewND);
9742 Decl *Sema::ActOnNamespaceAliasDef(Scope *S, SourceLocation NamespaceLoc,
9743 SourceLocation AliasLoc,
9744 IdentifierInfo *Alias, CXXScopeSpec &SS,
9745 SourceLocation IdentLoc,
9746 IdentifierInfo *Ident) {
9748 // Lookup the namespace name.
9749 LookupResult R(*this, Ident, IdentLoc, LookupNamespaceName);
9750 LookupParsedName(R, S, &SS);
9752 if (R.isAmbiguous())
9756 if (!TryNamespaceTypoCorrection(*this, R, S, SS, IdentLoc, Ident)) {
9757 Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange();
9761 assert(!R.isAmbiguous() && !R.empty());
9762 NamedDecl *ND = R.getRepresentativeDecl();
9764 // Check if we have a previous declaration with the same name.
9765 LookupResult PrevR(*this, Alias, AliasLoc, LookupOrdinaryName,
9767 LookupName(PrevR, S);
9769 // Check we're not shadowing a template parameter.
9770 if (PrevR.isSingleResult() && PrevR.getFoundDecl()->isTemplateParameter()) {
9771 DiagnoseTemplateParameterShadow(AliasLoc, PrevR.getFoundDecl());
9775 // Filter out any other lookup result from an enclosing scope.
9776 FilterLookupForScope(PrevR, CurContext, S, /*ConsiderLinkage*/false,
9777 /*AllowInlineNamespace*/false);
9779 // Find the previous declaration and check that we can redeclare it.
9780 NamespaceAliasDecl *Prev = nullptr;
9781 if (PrevR.isSingleResult()) {
9782 NamedDecl *PrevDecl = PrevR.getRepresentativeDecl();
9783 if (NamespaceAliasDecl *AD = dyn_cast<NamespaceAliasDecl>(PrevDecl)) {
9784 // We already have an alias with the same name that points to the same
9785 // namespace; check that it matches.
9786 if (AD->getNamespace()->Equals(getNamespaceDecl(ND))) {
9788 } else if (isVisible(PrevDecl)) {
9789 Diag(AliasLoc, diag::err_redefinition_different_namespace_alias)
9791 Diag(AD->getLocation(), diag::note_previous_namespace_alias)
9792 << AD->getNamespace();
9795 } else if (isVisible(PrevDecl)) {
9796 unsigned DiagID = isa<NamespaceDecl>(PrevDecl->getUnderlyingDecl())
9797 ? diag::err_redefinition
9798 : diag::err_redefinition_different_kind;
9799 Diag(AliasLoc, DiagID) << Alias;
9800 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
9805 // The use of a nested name specifier may trigger deprecation warnings.
9806 DiagnoseUseOfDecl(ND, IdentLoc);
9808 NamespaceAliasDecl *AliasDecl =
9809 NamespaceAliasDecl::Create(Context, CurContext, NamespaceLoc, AliasLoc,
9810 Alias, SS.getWithLocInContext(Context),
9813 AliasDecl->setPreviousDecl(Prev);
9815 PushOnScopeChains(AliasDecl, S);
9819 Sema::ImplicitExceptionSpecification
9820 Sema::ComputeDefaultedDefaultCtorExceptionSpec(SourceLocation Loc,
9821 CXXMethodDecl *MD) {
9822 CXXRecordDecl *ClassDecl = MD->getParent();
9824 // C++ [except.spec]p14:
9825 // An implicitly declared special member function (Clause 12) shall have an
9826 // exception-specification. [...]
9827 ImplicitExceptionSpecification ExceptSpec(*this);
9828 if (ClassDecl->isInvalidDecl())
9831 // Direct base-class constructors.
9832 for (const auto &B : ClassDecl->bases()) {
9833 if (B.isVirtual()) // Handled below.
9836 if (const RecordType *BaseType = B.getType()->getAs<RecordType>()) {
9837 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
9838 CXXConstructorDecl *Constructor = LookupDefaultConstructor(BaseClassDecl);
9839 // If this is a deleted function, add it anyway. This might be conformant
9840 // with the standard. This might not. I'm not sure. It might not matter.
9842 ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
9846 // Virtual base-class constructors.
9847 for (const auto &B : ClassDecl->vbases()) {
9848 if (const RecordType *BaseType = B.getType()->getAs<RecordType>()) {
9849 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
9850 CXXConstructorDecl *Constructor = LookupDefaultConstructor(BaseClassDecl);
9851 // If this is a deleted function, add it anyway. This might be conformant
9852 // with the standard. This might not. I'm not sure. It might not matter.
9854 ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
9858 // Field constructors.
9859 for (auto *F : ClassDecl->fields()) {
9860 if (F->hasInClassInitializer()) {
9861 Expr *E = F->getInClassInitializer();
9863 // FIXME: It's a little wasteful to build and throw away a
9864 // CXXDefaultInitExpr here.
9865 E = BuildCXXDefaultInitExpr(Loc, F).get();
9867 ExceptSpec.CalledExpr(E);
9868 } else if (const RecordType *RecordTy
9869 = Context.getBaseElementType(F->getType())->getAs<RecordType>()) {
9870 CXXRecordDecl *FieldRecDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
9871 CXXConstructorDecl *Constructor = LookupDefaultConstructor(FieldRecDecl);
9872 // If this is a deleted function, add it anyway. This might be conformant
9873 // with the standard. This might not. I'm not sure. It might not matter.
9874 // In particular, the problem is that this function never gets called. It
9875 // might just be ill-formed because this function attempts to refer to
9876 // a deleted function here.
9878 ExceptSpec.CalledDecl(F->getLocation(), Constructor);
9885 Sema::ImplicitExceptionSpecification
9886 Sema::ComputeInheritingCtorExceptionSpec(SourceLocation Loc,
9887 CXXConstructorDecl *CD) {
9888 CXXRecordDecl *ClassDecl = CD->getParent();
9890 // C++ [except.spec]p14:
9891 // An inheriting constructor [...] shall have an exception-specification. [...]
9892 ImplicitExceptionSpecification ExceptSpec(*this);
9893 if (ClassDecl->isInvalidDecl())
9896 auto Inherited = CD->getInheritedConstructor();
9897 InheritedConstructorInfo ICI(*this, Loc, Inherited.getShadowDecl());
9899 // Direct and virtual base-class constructors.
9900 for (bool VBase : {false, true}) {
9901 for (CXXBaseSpecifier &B :
9902 VBase ? ClassDecl->vbases() : ClassDecl->bases()) {
9903 // Don't visit direct vbases twice.
9904 if (B.isVirtual() != VBase)
9907 CXXRecordDecl *BaseClass = B.getType()->getAsCXXRecordDecl();
9911 CXXConstructorDecl *Constructor =
9912 ICI.findConstructorForBase(BaseClass, Inherited.getConstructor())
9915 Constructor = LookupDefaultConstructor(BaseClass);
9917 ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
9921 // Field constructors.
9922 for (const auto *F : ClassDecl->fields()) {
9923 if (F->hasInClassInitializer()) {
9924 if (Expr *E = F->getInClassInitializer())
9925 ExceptSpec.CalledExpr(E);
9926 } else if (const RecordType *RecordTy
9927 = Context.getBaseElementType(F->getType())->getAs<RecordType>()) {
9928 CXXRecordDecl *FieldRecDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
9929 CXXConstructorDecl *Constructor = LookupDefaultConstructor(FieldRecDecl);
9931 ExceptSpec.CalledDecl(F->getLocation(), Constructor);
9939 /// RAII object to register a special member as being currently declared.
9940 struct DeclaringSpecialMember {
9942 Sema::SpecialMemberDecl D;
9943 Sema::ContextRAII SavedContext;
9944 bool WasAlreadyBeingDeclared;
9946 DeclaringSpecialMember(Sema &S, CXXRecordDecl *RD, Sema::CXXSpecialMember CSM)
9947 : S(S), D(RD, CSM), SavedContext(S, RD) {
9948 WasAlreadyBeingDeclared = !S.SpecialMembersBeingDeclared.insert(D).second;
9949 if (WasAlreadyBeingDeclared)
9950 // This almost never happens, but if it does, ensure that our cache
9951 // doesn't contain a stale result.
9952 S.SpecialMemberCache.clear();
9954 // FIXME: Register a note to be produced if we encounter an error while
9955 // declaring the special member.
9957 ~DeclaringSpecialMember() {
9958 if (!WasAlreadyBeingDeclared)
9959 S.SpecialMembersBeingDeclared.erase(D);
9962 /// \brief Are we already trying to declare this special member?
9963 bool isAlreadyBeingDeclared() const {
9964 return WasAlreadyBeingDeclared;
9969 void Sema::CheckImplicitSpecialMemberDeclaration(Scope *S, FunctionDecl *FD) {
9970 // Look up any existing declarations, but don't trigger declaration of all
9971 // implicit special members with this name.
9972 DeclarationName Name = FD->getDeclName();
9973 LookupResult R(*this, Name, SourceLocation(), LookupOrdinaryName,
9975 for (auto *D : FD->getParent()->lookup(Name))
9976 if (auto *Acceptable = R.getAcceptableDecl(D))
9977 R.addDecl(Acceptable);
9979 R.suppressDiagnostics();
9981 CheckFunctionDeclaration(S, FD, R, /*IsExplicitSpecialization*/false);
9984 CXXConstructorDecl *Sema::DeclareImplicitDefaultConstructor(
9985 CXXRecordDecl *ClassDecl) {
9986 // C++ [class.ctor]p5:
9987 // A default constructor for a class X is a constructor of class X
9988 // that can be called without an argument. If there is no
9989 // user-declared constructor for class X, a default constructor is
9990 // implicitly declared. An implicitly-declared default constructor
9991 // is an inline public member of its class.
9992 assert(ClassDecl->needsImplicitDefaultConstructor() &&
9993 "Should not build implicit default constructor!");
9995 DeclaringSpecialMember DSM(*this, ClassDecl, CXXDefaultConstructor);
9996 if (DSM.isAlreadyBeingDeclared())
9999 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
10000 CXXDefaultConstructor,
10003 // Create the actual constructor declaration.
10004 CanQualType ClassType
10005 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
10006 SourceLocation ClassLoc = ClassDecl->getLocation();
10007 DeclarationName Name
10008 = Context.DeclarationNames.getCXXConstructorName(ClassType);
10009 DeclarationNameInfo NameInfo(Name, ClassLoc);
10010 CXXConstructorDecl *DefaultCon = CXXConstructorDecl::Create(
10011 Context, ClassDecl, ClassLoc, NameInfo, /*Type*/QualType(),
10012 /*TInfo=*/nullptr, /*isExplicit=*/false, /*isInline=*/true,
10013 /*isImplicitlyDeclared=*/true, Constexpr);
10014 DefaultCon->setAccess(AS_public);
10015 DefaultCon->setDefaulted();
10017 if (getLangOpts().CUDA) {
10018 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXDefaultConstructor,
10020 /* ConstRHS */ false,
10021 /* Diagnose */ false);
10024 // Build an exception specification pointing back at this constructor.
10025 FunctionProtoType::ExtProtoInfo EPI = getImplicitMethodEPI(*this, DefaultCon);
10026 DefaultCon->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
10028 // We don't need to use SpecialMemberIsTrivial here; triviality for default
10029 // constructors is easy to compute.
10030 DefaultCon->setTrivial(ClassDecl->hasTrivialDefaultConstructor());
10032 // Note that we have declared this constructor.
10033 ++ASTContext::NumImplicitDefaultConstructorsDeclared;
10035 Scope *S = getScopeForContext(ClassDecl);
10036 CheckImplicitSpecialMemberDeclaration(S, DefaultCon);
10038 if (ShouldDeleteSpecialMember(DefaultCon, CXXDefaultConstructor))
10039 SetDeclDeleted(DefaultCon, ClassLoc);
10042 PushOnScopeChains(DefaultCon, S, false);
10043 ClassDecl->addDecl(DefaultCon);
10048 void Sema::DefineImplicitDefaultConstructor(SourceLocation CurrentLocation,
10049 CXXConstructorDecl *Constructor) {
10050 assert((Constructor->isDefaulted() && Constructor->isDefaultConstructor() &&
10051 !Constructor->doesThisDeclarationHaveABody() &&
10052 !Constructor->isDeleted()) &&
10053 "DefineImplicitDefaultConstructor - call it for implicit default ctor");
10055 CXXRecordDecl *ClassDecl = Constructor->getParent();
10056 assert(ClassDecl && "DefineImplicitDefaultConstructor - invalid constructor");
10058 SynthesizedFunctionScope Scope(*this, Constructor);
10059 DiagnosticErrorTrap Trap(Diags);
10060 if (SetCtorInitializers(Constructor, /*AnyErrors=*/false) ||
10061 Trap.hasErrorOccurred()) {
10062 Diag(CurrentLocation, diag::note_member_synthesized_at)
10063 << CXXDefaultConstructor << Context.getTagDeclType(ClassDecl);
10064 Constructor->setInvalidDecl();
10068 // The exception specification is needed because we are defining the
10070 ResolveExceptionSpec(CurrentLocation,
10071 Constructor->getType()->castAs<FunctionProtoType>());
10073 SourceLocation Loc = Constructor->getLocEnd().isValid()
10074 ? Constructor->getLocEnd()
10075 : Constructor->getLocation();
10076 Constructor->setBody(new (Context) CompoundStmt(Loc));
10078 Constructor->markUsed(Context);
10079 MarkVTableUsed(CurrentLocation, ClassDecl);
10081 if (ASTMutationListener *L = getASTMutationListener()) {
10082 L->CompletedImplicitDefinition(Constructor);
10085 DiagnoseUninitializedFields(*this, Constructor);
10088 void Sema::ActOnFinishDelayedMemberInitializers(Decl *D) {
10089 // Perform any delayed checks on exception specifications.
10090 CheckDelayedMemberExceptionSpecs();
10093 /// Find or create the fake constructor we synthesize to model constructing an
10094 /// object of a derived class via a constructor of a base class.
10095 CXXConstructorDecl *
10096 Sema::findInheritingConstructor(SourceLocation Loc,
10097 CXXConstructorDecl *BaseCtor,
10098 ConstructorUsingShadowDecl *Shadow) {
10099 CXXRecordDecl *Derived = Shadow->getParent();
10100 SourceLocation UsingLoc = Shadow->getLocation();
10102 // FIXME: Add a new kind of DeclarationName for an inherited constructor.
10103 // For now we use the name of the base class constructor as a member of the
10104 // derived class to indicate a (fake) inherited constructor name.
10105 DeclarationName Name = BaseCtor->getDeclName();
10107 // Check to see if we already have a fake constructor for this inherited
10108 // constructor call.
10109 for (NamedDecl *Ctor : Derived->lookup(Name))
10110 if (declaresSameEntity(cast<CXXConstructorDecl>(Ctor)
10111 ->getInheritedConstructor()
10114 return cast<CXXConstructorDecl>(Ctor);
10116 DeclarationNameInfo NameInfo(Name, UsingLoc);
10117 TypeSourceInfo *TInfo =
10118 Context.getTrivialTypeSourceInfo(BaseCtor->getType(), UsingLoc);
10119 FunctionProtoTypeLoc ProtoLoc =
10120 TInfo->getTypeLoc().IgnoreParens().castAs<FunctionProtoTypeLoc>();
10122 // Check the inherited constructor is valid and find the list of base classes
10123 // from which it was inherited.
10124 InheritedConstructorInfo ICI(*this, Loc, Shadow);
10127 BaseCtor->isConstexpr() &&
10128 defaultedSpecialMemberIsConstexpr(*this, Derived, CXXDefaultConstructor,
10129 false, BaseCtor, &ICI);
10131 CXXConstructorDecl *DerivedCtor = CXXConstructorDecl::Create(
10132 Context, Derived, UsingLoc, NameInfo, TInfo->getType(), TInfo,
10133 BaseCtor->isExplicit(), /*Inline=*/true,
10134 /*ImplicitlyDeclared=*/true, Constexpr,
10135 InheritedConstructor(Shadow, BaseCtor));
10136 if (Shadow->isInvalidDecl())
10137 DerivedCtor->setInvalidDecl();
10139 // Build an unevaluated exception specification for this fake constructor.
10140 const FunctionProtoType *FPT = TInfo->getType()->castAs<FunctionProtoType>();
10141 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
10142 EPI.ExceptionSpec.Type = EST_Unevaluated;
10143 EPI.ExceptionSpec.SourceDecl = DerivedCtor;
10144 DerivedCtor->setType(Context.getFunctionType(FPT->getReturnType(),
10145 FPT->getParamTypes(), EPI));
10147 // Build the parameter declarations.
10148 SmallVector<ParmVarDecl *, 16> ParamDecls;
10149 for (unsigned I = 0, N = FPT->getNumParams(); I != N; ++I) {
10150 TypeSourceInfo *TInfo =
10151 Context.getTrivialTypeSourceInfo(FPT->getParamType(I), UsingLoc);
10152 ParmVarDecl *PD = ParmVarDecl::Create(
10153 Context, DerivedCtor, UsingLoc, UsingLoc, /*IdentifierInfo=*/nullptr,
10154 FPT->getParamType(I), TInfo, SC_None, /*DefaultArg=*/nullptr);
10155 PD->setScopeInfo(0, I);
10157 // Ensure attributes are propagated onto parameters (this matters for
10158 // format, pass_object_size, ...).
10159 mergeDeclAttributes(PD, BaseCtor->getParamDecl(I));
10160 ParamDecls.push_back(PD);
10161 ProtoLoc.setParam(I, PD);
10164 // Set up the new constructor.
10165 assert(!BaseCtor->isDeleted() && "should not use deleted constructor");
10166 DerivedCtor->setAccess(BaseCtor->getAccess());
10167 DerivedCtor->setParams(ParamDecls);
10168 Derived->addDecl(DerivedCtor);
10170 if (ShouldDeleteSpecialMember(DerivedCtor, CXXDefaultConstructor, &ICI))
10171 SetDeclDeleted(DerivedCtor, UsingLoc);
10173 return DerivedCtor;
10176 void Sema::NoteDeletedInheritingConstructor(CXXConstructorDecl *Ctor) {
10177 InheritedConstructorInfo ICI(*this, Ctor->getLocation(),
10178 Ctor->getInheritedConstructor().getShadowDecl());
10179 ShouldDeleteSpecialMember(Ctor, CXXDefaultConstructor, &ICI,
10183 void Sema::DefineInheritingConstructor(SourceLocation CurrentLocation,
10184 CXXConstructorDecl *Constructor) {
10185 CXXRecordDecl *ClassDecl = Constructor->getParent();
10186 assert(Constructor->getInheritedConstructor() &&
10187 !Constructor->doesThisDeclarationHaveABody() &&
10188 !Constructor->isDeleted());
10189 if (Constructor->isInvalidDecl())
10192 ConstructorUsingShadowDecl *Shadow =
10193 Constructor->getInheritedConstructor().getShadowDecl();
10194 CXXConstructorDecl *InheritedCtor =
10195 Constructor->getInheritedConstructor().getConstructor();
10197 // [class.inhctor.init]p1:
10198 // initialization proceeds as if a defaulted default constructor is used to
10199 // initialize the D object and each base class subobject from which the
10200 // constructor was inherited
10202 InheritedConstructorInfo ICI(*this, CurrentLocation, Shadow);
10203 CXXRecordDecl *RD = Shadow->getParent();
10204 SourceLocation InitLoc = Shadow->getLocation();
10206 // Initializations are performed "as if by a defaulted default constructor",
10207 // so enter the appropriate scope.
10208 SynthesizedFunctionScope Scope(*this, Constructor);
10209 DiagnosticErrorTrap Trap(Diags);
10211 // Build explicit initializers for all base classes from which the
10212 // constructor was inherited.
10213 SmallVector<CXXCtorInitializer*, 8> Inits;
10214 for (bool VBase : {false, true}) {
10215 for (CXXBaseSpecifier &B : VBase ? RD->vbases() : RD->bases()) {
10216 if (B.isVirtual() != VBase)
10219 auto *BaseRD = B.getType()->getAsCXXRecordDecl();
10223 auto BaseCtor = ICI.findConstructorForBase(BaseRD, InheritedCtor);
10224 if (!BaseCtor.first)
10227 MarkFunctionReferenced(CurrentLocation, BaseCtor.first);
10228 ExprResult Init = new (Context) CXXInheritedCtorInitExpr(
10229 InitLoc, B.getType(), BaseCtor.first, VBase, BaseCtor.second);
10231 auto *TInfo = Context.getTrivialTypeSourceInfo(B.getType(), InitLoc);
10232 Inits.push_back(new (Context) CXXCtorInitializer(
10233 Context, TInfo, VBase, InitLoc, Init.get(), InitLoc,
10234 SourceLocation()));
10238 // We now proceed as if for a defaulted default constructor, with the relevant
10239 // initializers replaced.
10241 bool HadError = SetCtorInitializers(Constructor, /*AnyErrors*/false, Inits);
10242 if (HadError || Trap.hasErrorOccurred()) {
10243 Diag(CurrentLocation, diag::note_inhctor_synthesized_at) << RD;
10244 Constructor->setInvalidDecl();
10248 // The exception specification is needed because we are defining the
10250 ResolveExceptionSpec(CurrentLocation,
10251 Constructor->getType()->castAs<FunctionProtoType>());
10253 Constructor->setBody(new (Context) CompoundStmt(InitLoc));
10255 Constructor->markUsed(Context);
10256 MarkVTableUsed(CurrentLocation, ClassDecl);
10258 if (ASTMutationListener *L = getASTMutationListener()) {
10259 L->CompletedImplicitDefinition(Constructor);
10262 DiagnoseUninitializedFields(*this, Constructor);
10265 Sema::ImplicitExceptionSpecification
10266 Sema::ComputeDefaultedDtorExceptionSpec(CXXMethodDecl *MD) {
10267 CXXRecordDecl *ClassDecl = MD->getParent();
10269 // C++ [except.spec]p14:
10270 // An implicitly declared special member function (Clause 12) shall have
10271 // an exception-specification.
10272 ImplicitExceptionSpecification ExceptSpec(*this);
10273 if (ClassDecl->isInvalidDecl())
10276 // Direct base-class destructors.
10277 for (const auto &B : ClassDecl->bases()) {
10278 if (B.isVirtual()) // Handled below.
10281 if (const RecordType *BaseType = B.getType()->getAs<RecordType>())
10282 ExceptSpec.CalledDecl(B.getLocStart(),
10283 LookupDestructor(cast<CXXRecordDecl>(BaseType->getDecl())));
10286 // Virtual base-class destructors.
10287 for (const auto &B : ClassDecl->vbases()) {
10288 if (const RecordType *BaseType = B.getType()->getAs<RecordType>())
10289 ExceptSpec.CalledDecl(B.getLocStart(),
10290 LookupDestructor(cast<CXXRecordDecl>(BaseType->getDecl())));
10293 // Field destructors.
10294 for (const auto *F : ClassDecl->fields()) {
10295 if (const RecordType *RecordTy
10296 = Context.getBaseElementType(F->getType())->getAs<RecordType>())
10297 ExceptSpec.CalledDecl(F->getLocation(),
10298 LookupDestructor(cast<CXXRecordDecl>(RecordTy->getDecl())));
10304 CXXDestructorDecl *Sema::DeclareImplicitDestructor(CXXRecordDecl *ClassDecl) {
10305 // C++ [class.dtor]p2:
10306 // If a class has no user-declared destructor, a destructor is
10307 // declared implicitly. An implicitly-declared destructor is an
10308 // inline public member of its class.
10309 assert(ClassDecl->needsImplicitDestructor());
10311 DeclaringSpecialMember DSM(*this, ClassDecl, CXXDestructor);
10312 if (DSM.isAlreadyBeingDeclared())
10315 // Create the actual destructor declaration.
10316 CanQualType ClassType
10317 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
10318 SourceLocation ClassLoc = ClassDecl->getLocation();
10319 DeclarationName Name
10320 = Context.DeclarationNames.getCXXDestructorName(ClassType);
10321 DeclarationNameInfo NameInfo(Name, ClassLoc);
10322 CXXDestructorDecl *Destructor
10323 = CXXDestructorDecl::Create(Context, ClassDecl, ClassLoc, NameInfo,
10324 QualType(), nullptr, /*isInline=*/true,
10325 /*isImplicitlyDeclared=*/true);
10326 Destructor->setAccess(AS_public);
10327 Destructor->setDefaulted();
10329 if (getLangOpts().CUDA) {
10330 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXDestructor,
10332 /* ConstRHS */ false,
10333 /* Diagnose */ false);
10336 // Build an exception specification pointing back at this destructor.
10337 FunctionProtoType::ExtProtoInfo EPI = getImplicitMethodEPI(*this, Destructor);
10338 Destructor->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
10340 // We don't need to use SpecialMemberIsTrivial here; triviality for
10341 // destructors is easy to compute.
10342 Destructor->setTrivial(ClassDecl->hasTrivialDestructor());
10344 // Note that we have declared this destructor.
10345 ++ASTContext::NumImplicitDestructorsDeclared;
10347 Scope *S = getScopeForContext(ClassDecl);
10348 CheckImplicitSpecialMemberDeclaration(S, Destructor);
10350 // We can't check whether an implicit destructor is deleted before we complete
10351 // the definition of the class, because its validity depends on the alignment
10352 // of the class. We'll check this from ActOnFields once the class is complete.
10353 if (ClassDecl->isCompleteDefinition() &&
10354 ShouldDeleteSpecialMember(Destructor, CXXDestructor))
10355 SetDeclDeleted(Destructor, ClassLoc);
10357 // Introduce this destructor into its scope.
10359 PushOnScopeChains(Destructor, S, false);
10360 ClassDecl->addDecl(Destructor);
10365 void Sema::DefineImplicitDestructor(SourceLocation CurrentLocation,
10366 CXXDestructorDecl *Destructor) {
10367 assert((Destructor->isDefaulted() &&
10368 !Destructor->doesThisDeclarationHaveABody() &&
10369 !Destructor->isDeleted()) &&
10370 "DefineImplicitDestructor - call it for implicit default dtor");
10371 CXXRecordDecl *ClassDecl = Destructor->getParent();
10372 assert(ClassDecl && "DefineImplicitDestructor - invalid destructor");
10374 if (Destructor->isInvalidDecl())
10377 SynthesizedFunctionScope Scope(*this, Destructor);
10379 DiagnosticErrorTrap Trap(Diags);
10380 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
10381 Destructor->getParent());
10383 if (CheckDestructor(Destructor) || Trap.hasErrorOccurred()) {
10384 Diag(CurrentLocation, diag::note_member_synthesized_at)
10385 << CXXDestructor << Context.getTagDeclType(ClassDecl);
10387 Destructor->setInvalidDecl();
10391 // The exception specification is needed because we are defining the
10393 ResolveExceptionSpec(CurrentLocation,
10394 Destructor->getType()->castAs<FunctionProtoType>());
10396 SourceLocation Loc = Destructor->getLocEnd().isValid()
10397 ? Destructor->getLocEnd()
10398 : Destructor->getLocation();
10399 Destructor->setBody(new (Context) CompoundStmt(Loc));
10400 Destructor->markUsed(Context);
10401 MarkVTableUsed(CurrentLocation, ClassDecl);
10403 if (ASTMutationListener *L = getASTMutationListener()) {
10404 L->CompletedImplicitDefinition(Destructor);
10408 /// \brief Perform any semantic analysis which needs to be delayed until all
10409 /// pending class member declarations have been parsed.
10410 void Sema::ActOnFinishCXXMemberDecls() {
10411 // If the context is an invalid C++ class, just suppress these checks.
10412 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(CurContext)) {
10413 if (Record->isInvalidDecl()) {
10414 DelayedDefaultedMemberExceptionSpecs.clear();
10415 DelayedExceptionSpecChecks.clear();
10418 checkForMultipleExportedDefaultConstructors(*this, Record);
10422 void Sema::ActOnFinishCXXNonNestedClass(Decl *D) {
10423 referenceDLLExportedClassMethods();
10426 void Sema::referenceDLLExportedClassMethods() {
10427 if (!DelayedDllExportClasses.empty()) {
10428 // Calling ReferenceDllExportedMethods might cause the current function to
10429 // be called again, so use a local copy of DelayedDllExportClasses.
10430 SmallVector<CXXRecordDecl *, 4> WorkList;
10431 std::swap(DelayedDllExportClasses, WorkList);
10432 for (CXXRecordDecl *Class : WorkList)
10433 ReferenceDllExportedMethods(*this, Class);
10437 void Sema::AdjustDestructorExceptionSpec(CXXRecordDecl *ClassDecl,
10438 CXXDestructorDecl *Destructor) {
10439 assert(getLangOpts().CPlusPlus11 &&
10440 "adjusting dtor exception specs was introduced in c++11");
10442 // C++11 [class.dtor]p3:
10443 // A declaration of a destructor that does not have an exception-
10444 // specification is implicitly considered to have the same exception-
10445 // specification as an implicit declaration.
10446 const FunctionProtoType *DtorType = Destructor->getType()->
10447 getAs<FunctionProtoType>();
10448 if (DtorType->hasExceptionSpec())
10451 // Replace the destructor's type, building off the existing one. Fortunately,
10452 // the only thing of interest in the destructor type is its extended info.
10453 // The return and arguments are fixed.
10454 FunctionProtoType::ExtProtoInfo EPI = DtorType->getExtProtoInfo();
10455 EPI.ExceptionSpec.Type = EST_Unevaluated;
10456 EPI.ExceptionSpec.SourceDecl = Destructor;
10457 Destructor->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
10459 // FIXME: If the destructor has a body that could throw, and the newly created
10460 // spec doesn't allow exceptions, we should emit a warning, because this
10461 // change in behavior can break conforming C++03 programs at runtime.
10462 // However, we don't have a body or an exception specification yet, so it
10463 // needs to be done somewhere else.
10467 /// \brief An abstract base class for all helper classes used in building the
10468 // copy/move operators. These classes serve as factory functions and help us
10469 // avoid using the same Expr* in the AST twice.
10470 class ExprBuilder {
10471 ExprBuilder(const ExprBuilder&) = delete;
10472 ExprBuilder &operator=(const ExprBuilder&) = delete;
10475 static Expr *assertNotNull(Expr *E) {
10476 assert(E && "Expression construction must not fail.");
10482 virtual ~ExprBuilder() {}
10484 virtual Expr *build(Sema &S, SourceLocation Loc) const = 0;
10487 class RefBuilder: public ExprBuilder {
10492 Expr *build(Sema &S, SourceLocation Loc) const override {
10493 return assertNotNull(S.BuildDeclRefExpr(Var, VarType, VK_LValue, Loc).get());
10496 RefBuilder(VarDecl *Var, QualType VarType)
10497 : Var(Var), VarType(VarType) {}
10500 class ThisBuilder: public ExprBuilder {
10502 Expr *build(Sema &S, SourceLocation Loc) const override {
10503 return assertNotNull(S.ActOnCXXThis(Loc).getAs<Expr>());
10507 class CastBuilder: public ExprBuilder {
10508 const ExprBuilder &Builder;
10510 ExprValueKind Kind;
10511 const CXXCastPath &Path;
10514 Expr *build(Sema &S, SourceLocation Loc) const override {
10515 return assertNotNull(S.ImpCastExprToType(Builder.build(S, Loc), Type,
10516 CK_UncheckedDerivedToBase, Kind,
10520 CastBuilder(const ExprBuilder &Builder, QualType Type, ExprValueKind Kind,
10521 const CXXCastPath &Path)
10522 : Builder(Builder), Type(Type), Kind(Kind), Path(Path) {}
10525 class DerefBuilder: public ExprBuilder {
10526 const ExprBuilder &Builder;
10529 Expr *build(Sema &S, SourceLocation Loc) const override {
10530 return assertNotNull(
10531 S.CreateBuiltinUnaryOp(Loc, UO_Deref, Builder.build(S, Loc)).get());
10534 DerefBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
10537 class MemberBuilder: public ExprBuilder {
10538 const ExprBuilder &Builder;
10542 LookupResult &MemberLookup;
10545 Expr *build(Sema &S, SourceLocation Loc) const override {
10546 return assertNotNull(S.BuildMemberReferenceExpr(
10547 Builder.build(S, Loc), Type, Loc, IsArrow, SS, SourceLocation(),
10548 nullptr, MemberLookup, nullptr, nullptr).get());
10551 MemberBuilder(const ExprBuilder &Builder, QualType Type, bool IsArrow,
10552 LookupResult &MemberLookup)
10553 : Builder(Builder), Type(Type), IsArrow(IsArrow),
10554 MemberLookup(MemberLookup) {}
10557 class MoveCastBuilder: public ExprBuilder {
10558 const ExprBuilder &Builder;
10561 Expr *build(Sema &S, SourceLocation Loc) const override {
10562 return assertNotNull(CastForMoving(S, Builder.build(S, Loc)));
10565 MoveCastBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
10568 class LvalueConvBuilder: public ExprBuilder {
10569 const ExprBuilder &Builder;
10572 Expr *build(Sema &S, SourceLocation Loc) const override {
10573 return assertNotNull(
10574 S.DefaultLvalueConversion(Builder.build(S, Loc)).get());
10577 LvalueConvBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
10580 class SubscriptBuilder: public ExprBuilder {
10581 const ExprBuilder &Base;
10582 const ExprBuilder &Index;
10585 Expr *build(Sema &S, SourceLocation Loc) const override {
10586 return assertNotNull(S.CreateBuiltinArraySubscriptExpr(
10587 Base.build(S, Loc), Loc, Index.build(S, Loc), Loc).get());
10590 SubscriptBuilder(const ExprBuilder &Base, const ExprBuilder &Index)
10591 : Base(Base), Index(Index) {}
10594 } // end anonymous namespace
10596 /// When generating a defaulted copy or move assignment operator, if a field
10597 /// should be copied with __builtin_memcpy rather than via explicit assignments,
10598 /// do so. This optimization only applies for arrays of scalars, and for arrays
10599 /// of class type where the selected copy/move-assignment operator is trivial.
10601 buildMemcpyForAssignmentOp(Sema &S, SourceLocation Loc, QualType T,
10602 const ExprBuilder &ToB, const ExprBuilder &FromB) {
10603 // Compute the size of the memory buffer to be copied.
10604 QualType SizeType = S.Context.getSizeType();
10605 llvm::APInt Size(S.Context.getTypeSize(SizeType),
10606 S.Context.getTypeSizeInChars(T).getQuantity());
10608 // Take the address of the field references for "from" and "to". We
10609 // directly construct UnaryOperators here because semantic analysis
10610 // does not permit us to take the address of an xvalue.
10611 Expr *From = FromB.build(S, Loc);
10612 From = new (S.Context) UnaryOperator(From, UO_AddrOf,
10613 S.Context.getPointerType(From->getType()),
10614 VK_RValue, OK_Ordinary, Loc);
10615 Expr *To = ToB.build(S, Loc);
10616 To = new (S.Context) UnaryOperator(To, UO_AddrOf,
10617 S.Context.getPointerType(To->getType()),
10618 VK_RValue, OK_Ordinary, Loc);
10620 const Type *E = T->getBaseElementTypeUnsafe();
10621 bool NeedsCollectableMemCpy =
10622 E->isRecordType() && E->getAs<RecordType>()->getDecl()->hasObjectMember();
10624 // Create a reference to the __builtin_objc_memmove_collectable function
10625 StringRef MemCpyName = NeedsCollectableMemCpy ?
10626 "__builtin_objc_memmove_collectable" :
10627 "__builtin_memcpy";
10628 LookupResult R(S, &S.Context.Idents.get(MemCpyName), Loc,
10629 Sema::LookupOrdinaryName);
10630 S.LookupName(R, S.TUScope, true);
10632 FunctionDecl *MemCpy = R.getAsSingle<FunctionDecl>();
10634 // Something went horribly wrong earlier, and we will have complained
10636 return StmtError();
10638 ExprResult MemCpyRef = S.BuildDeclRefExpr(MemCpy, S.Context.BuiltinFnTy,
10639 VK_RValue, Loc, nullptr);
10640 assert(MemCpyRef.isUsable() && "Builtin reference cannot fail");
10642 Expr *CallArgs[] = {
10643 To, From, IntegerLiteral::Create(S.Context, Size, SizeType, Loc)
10645 ExprResult Call = S.ActOnCallExpr(/*Scope=*/nullptr, MemCpyRef.get(),
10646 Loc, CallArgs, Loc);
10648 assert(!Call.isInvalid() && "Call to __builtin_memcpy cannot fail!");
10649 return Call.getAs<Stmt>();
10652 /// \brief Builds a statement that copies/moves the given entity from \p From to
10655 /// This routine is used to copy/move the members of a class with an
10656 /// implicitly-declared copy/move assignment operator. When the entities being
10657 /// copied are arrays, this routine builds for loops to copy them.
10659 /// \param S The Sema object used for type-checking.
10661 /// \param Loc The location where the implicit copy/move is being generated.
10663 /// \param T The type of the expressions being copied/moved. Both expressions
10664 /// must have this type.
10666 /// \param To The expression we are copying/moving to.
10668 /// \param From The expression we are copying/moving from.
10670 /// \param CopyingBaseSubobject Whether we're copying/moving a base subobject.
10671 /// Otherwise, it's a non-static member subobject.
10673 /// \param Copying Whether we're copying or moving.
10675 /// \param Depth Internal parameter recording the depth of the recursion.
10677 /// \returns A statement or a loop that copies the expressions, or StmtResult(0)
10678 /// if a memcpy should be used instead.
10680 buildSingleCopyAssignRecursively(Sema &S, SourceLocation Loc, QualType T,
10681 const ExprBuilder &To, const ExprBuilder &From,
10682 bool CopyingBaseSubobject, bool Copying,
10683 unsigned Depth = 0) {
10684 // C++11 [class.copy]p28:
10685 // Each subobject is assigned in the manner appropriate to its type:
10687 // - if the subobject is of class type, as if by a call to operator= with
10688 // the subobject as the object expression and the corresponding
10689 // subobject of x as a single function argument (as if by explicit
10690 // qualification; that is, ignoring any possible virtual overriding
10691 // functions in more derived classes);
10693 // C++03 [class.copy]p13:
10694 // - if the subobject is of class type, the copy assignment operator for
10695 // the class is used (as if by explicit qualification; that is,
10696 // ignoring any possible virtual overriding functions in more derived
10698 if (const RecordType *RecordTy = T->getAs<RecordType>()) {
10699 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
10701 // Look for operator=.
10702 DeclarationName Name
10703 = S.Context.DeclarationNames.getCXXOperatorName(OO_Equal);
10704 LookupResult OpLookup(S, Name, Loc, Sema::LookupOrdinaryName);
10705 S.LookupQualifiedName(OpLookup, ClassDecl, false);
10707 // Prior to C++11, filter out any result that isn't a copy/move-assignment
10709 if (!S.getLangOpts().CPlusPlus11) {
10710 LookupResult::Filter F = OpLookup.makeFilter();
10711 while (F.hasNext()) {
10712 NamedDecl *D = F.next();
10713 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
10714 if (Method->isCopyAssignmentOperator() ||
10715 (!Copying && Method->isMoveAssignmentOperator()))
10723 // Suppress the protected check (C++ [class.protected]) for each of the
10724 // assignment operators we found. This strange dance is required when
10725 // we're assigning via a base classes's copy-assignment operator. To
10726 // ensure that we're getting the right base class subobject (without
10727 // ambiguities), we need to cast "this" to that subobject type; to
10728 // ensure that we don't go through the virtual call mechanism, we need
10729 // to qualify the operator= name with the base class (see below). However,
10730 // this means that if the base class has a protected copy assignment
10731 // operator, the protected member access check will fail. So, we
10732 // rewrite "protected" access to "public" access in this case, since we
10733 // know by construction that we're calling from a derived class.
10734 if (CopyingBaseSubobject) {
10735 for (LookupResult::iterator L = OpLookup.begin(), LEnd = OpLookup.end();
10737 if (L.getAccess() == AS_protected)
10738 L.setAccess(AS_public);
10742 // Create the nested-name-specifier that will be used to qualify the
10743 // reference to operator=; this is required to suppress the virtual
10746 const Type *CanonicalT = S.Context.getCanonicalType(T.getTypePtr());
10747 SS.MakeTrivial(S.Context,
10748 NestedNameSpecifier::Create(S.Context, nullptr, false,
10752 // Create the reference to operator=.
10753 ExprResult OpEqualRef
10754 = S.BuildMemberReferenceExpr(To.build(S, Loc), T, Loc, /*isArrow=*/false,
10755 SS, /*TemplateKWLoc=*/SourceLocation(),
10756 /*FirstQualifierInScope=*/nullptr,
10758 /*TemplateArgs=*/nullptr, /*S*/nullptr,
10759 /*SuppressQualifierCheck=*/true);
10760 if (OpEqualRef.isInvalid())
10761 return StmtError();
10763 // Build the call to the assignment operator.
10765 Expr *FromInst = From.build(S, Loc);
10766 ExprResult Call = S.BuildCallToMemberFunction(/*Scope=*/nullptr,
10767 OpEqualRef.getAs<Expr>(),
10768 Loc, FromInst, Loc);
10769 if (Call.isInvalid())
10770 return StmtError();
10772 // If we built a call to a trivial 'operator=' while copying an array,
10773 // bail out. We'll replace the whole shebang with a memcpy.
10774 CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(Call.get());
10775 if (CE && CE->getMethodDecl()->isTrivial() && Depth)
10776 return StmtResult((Stmt*)nullptr);
10778 // Convert to an expression-statement, and clean up any produced
10780 return S.ActOnExprStmt(Call);
10783 // - if the subobject is of scalar type, the built-in assignment
10784 // operator is used.
10785 const ConstantArrayType *ArrayTy = S.Context.getAsConstantArrayType(T);
10787 ExprResult Assignment = S.CreateBuiltinBinOp(
10788 Loc, BO_Assign, To.build(S, Loc), From.build(S, Loc));
10789 if (Assignment.isInvalid())
10790 return StmtError();
10791 return S.ActOnExprStmt(Assignment);
10794 // - if the subobject is an array, each element is assigned, in the
10795 // manner appropriate to the element type;
10797 // Construct a loop over the array bounds, e.g.,
10799 // for (__SIZE_TYPE__ i0 = 0; i0 != array-size; ++i0)
10801 // that will copy each of the array elements.
10802 QualType SizeType = S.Context.getSizeType();
10804 // Create the iteration variable.
10805 IdentifierInfo *IterationVarName = nullptr;
10807 SmallString<8> Str;
10808 llvm::raw_svector_ostream OS(Str);
10809 OS << "__i" << Depth;
10810 IterationVarName = &S.Context.Idents.get(OS.str());
10812 VarDecl *IterationVar = VarDecl::Create(S.Context, S.CurContext, Loc, Loc,
10813 IterationVarName, SizeType,
10814 S.Context.getTrivialTypeSourceInfo(SizeType, Loc),
10817 // Initialize the iteration variable to zero.
10818 llvm::APInt Zero(S.Context.getTypeSize(SizeType), 0);
10819 IterationVar->setInit(IntegerLiteral::Create(S.Context, Zero, SizeType, Loc));
10821 // Creates a reference to the iteration variable.
10822 RefBuilder IterationVarRef(IterationVar, SizeType);
10823 LvalueConvBuilder IterationVarRefRVal(IterationVarRef);
10825 // Create the DeclStmt that holds the iteration variable.
10826 Stmt *InitStmt = new (S.Context) DeclStmt(DeclGroupRef(IterationVar),Loc,Loc);
10828 // Subscript the "from" and "to" expressions with the iteration variable.
10829 SubscriptBuilder FromIndexCopy(From, IterationVarRefRVal);
10830 MoveCastBuilder FromIndexMove(FromIndexCopy);
10831 const ExprBuilder *FromIndex;
10833 FromIndex = &FromIndexCopy;
10835 FromIndex = &FromIndexMove;
10837 SubscriptBuilder ToIndex(To, IterationVarRefRVal);
10839 // Build the copy/move for an individual element of the array.
10841 buildSingleCopyAssignRecursively(S, Loc, ArrayTy->getElementType(),
10842 ToIndex, *FromIndex, CopyingBaseSubobject,
10843 Copying, Depth + 1);
10844 // Bail out if copying fails or if we determined that we should use memcpy.
10845 if (Copy.isInvalid() || !Copy.get())
10848 // Create the comparison against the array bound.
10850 = ArrayTy->getSize().zextOrTrunc(S.Context.getTypeSize(SizeType));
10852 = new (S.Context) BinaryOperator(IterationVarRefRVal.build(S, Loc),
10853 IntegerLiteral::Create(S.Context, Upper, SizeType, Loc),
10854 BO_NE, S.Context.BoolTy,
10855 VK_RValue, OK_Ordinary, Loc, false);
10857 // Create the pre-increment of the iteration variable.
10859 = new (S.Context) UnaryOperator(IterationVarRef.build(S, Loc), UO_PreInc,
10860 SizeType, VK_LValue, OK_Ordinary, Loc);
10862 // Construct the loop that copies all elements of this array.
10863 return S.ActOnForStmt(
10864 Loc, Loc, InitStmt,
10865 S.ActOnCondition(nullptr, Loc, Comparison, Sema::ConditionKind::Boolean),
10866 S.MakeFullDiscardedValueExpr(Increment), Loc, Copy.get());
10870 buildSingleCopyAssign(Sema &S, SourceLocation Loc, QualType T,
10871 const ExprBuilder &To, const ExprBuilder &From,
10872 bool CopyingBaseSubobject, bool Copying) {
10873 // Maybe we should use a memcpy?
10874 if (T->isArrayType() && !T.isConstQualified() && !T.isVolatileQualified() &&
10875 T.isTriviallyCopyableType(S.Context))
10876 return buildMemcpyForAssignmentOp(S, Loc, T, To, From);
10878 StmtResult Result(buildSingleCopyAssignRecursively(S, Loc, T, To, From,
10879 CopyingBaseSubobject,
10882 // If we ended up picking a trivial assignment operator for an array of a
10883 // non-trivially-copyable class type, just emit a memcpy.
10884 if (!Result.isInvalid() && !Result.get())
10885 return buildMemcpyForAssignmentOp(S, Loc, T, To, From);
10890 Sema::ImplicitExceptionSpecification
10891 Sema::ComputeDefaultedCopyAssignmentExceptionSpec(CXXMethodDecl *MD) {
10892 CXXRecordDecl *ClassDecl = MD->getParent();
10894 ImplicitExceptionSpecification ExceptSpec(*this);
10895 if (ClassDecl->isInvalidDecl())
10898 const FunctionProtoType *T = MD->getType()->castAs<FunctionProtoType>();
10899 assert(T->getNumParams() == 1 && "not a copy assignment op");
10900 unsigned ArgQuals =
10901 T->getParamType(0).getNonReferenceType().getCVRQualifiers();
10903 // C++ [except.spec]p14:
10904 // An implicitly declared special member function (Clause 12) shall have an
10905 // exception-specification. [...]
10907 // It is unspecified whether or not an implicit copy assignment operator
10908 // attempts to deduplicate calls to assignment operators of virtual bases are
10909 // made. As such, this exception specification is effectively unspecified.
10910 // Based on a similar decision made for constness in C++0x, we're erring on
10911 // the side of assuming such calls to be made regardless of whether they
10912 // actually happen.
10913 for (const auto &Base : ClassDecl->bases()) {
10914 if (Base.isVirtual())
10917 CXXRecordDecl *BaseClassDecl
10918 = cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
10919 if (CXXMethodDecl *CopyAssign = LookupCopyingAssignment(BaseClassDecl,
10920 ArgQuals, false, 0))
10921 ExceptSpec.CalledDecl(Base.getLocStart(), CopyAssign);
10924 for (const auto &Base : ClassDecl->vbases()) {
10925 CXXRecordDecl *BaseClassDecl
10926 = cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
10927 if (CXXMethodDecl *CopyAssign = LookupCopyingAssignment(BaseClassDecl,
10928 ArgQuals, false, 0))
10929 ExceptSpec.CalledDecl(Base.getLocStart(), CopyAssign);
10932 for (const auto *Field : ClassDecl->fields()) {
10933 QualType FieldType = Context.getBaseElementType(Field->getType());
10934 if (CXXRecordDecl *FieldClassDecl = FieldType->getAsCXXRecordDecl()) {
10935 if (CXXMethodDecl *CopyAssign =
10936 LookupCopyingAssignment(FieldClassDecl,
10937 ArgQuals | FieldType.getCVRQualifiers(),
10939 ExceptSpec.CalledDecl(Field->getLocation(), CopyAssign);
10946 CXXMethodDecl *Sema::DeclareImplicitCopyAssignment(CXXRecordDecl *ClassDecl) {
10947 // Note: The following rules are largely analoguous to the copy
10948 // constructor rules. Note that virtual bases are not taken into account
10949 // for determining the argument type of the operator. Note also that
10950 // operators taking an object instead of a reference are allowed.
10951 assert(ClassDecl->needsImplicitCopyAssignment());
10953 DeclaringSpecialMember DSM(*this, ClassDecl, CXXCopyAssignment);
10954 if (DSM.isAlreadyBeingDeclared())
10957 QualType ArgType = Context.getTypeDeclType(ClassDecl);
10958 QualType RetType = Context.getLValueReferenceType(ArgType);
10959 bool Const = ClassDecl->implicitCopyAssignmentHasConstParam();
10961 ArgType = ArgType.withConst();
10962 ArgType = Context.getLValueReferenceType(ArgType);
10964 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
10968 // An implicitly-declared copy assignment operator is an inline public
10969 // member of its class.
10970 DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
10971 SourceLocation ClassLoc = ClassDecl->getLocation();
10972 DeclarationNameInfo NameInfo(Name, ClassLoc);
10973 CXXMethodDecl *CopyAssignment =
10974 CXXMethodDecl::Create(Context, ClassDecl, ClassLoc, NameInfo, QualType(),
10975 /*TInfo=*/nullptr, /*StorageClass=*/SC_None,
10976 /*isInline=*/true, Constexpr, SourceLocation());
10977 CopyAssignment->setAccess(AS_public);
10978 CopyAssignment->setDefaulted();
10979 CopyAssignment->setImplicit();
10981 if (getLangOpts().CUDA) {
10982 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXCopyAssignment,
10984 /* ConstRHS */ Const,
10985 /* Diagnose */ false);
10988 // Build an exception specification pointing back at this member.
10989 FunctionProtoType::ExtProtoInfo EPI =
10990 getImplicitMethodEPI(*this, CopyAssignment);
10991 CopyAssignment->setType(Context.getFunctionType(RetType, ArgType, EPI));
10993 // Add the parameter to the operator.
10994 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyAssignment,
10995 ClassLoc, ClassLoc,
10996 /*Id=*/nullptr, ArgType,
10997 /*TInfo=*/nullptr, SC_None,
10999 CopyAssignment->setParams(FromParam);
11001 CopyAssignment->setTrivial(
11002 ClassDecl->needsOverloadResolutionForCopyAssignment()
11003 ? SpecialMemberIsTrivial(CopyAssignment, CXXCopyAssignment)
11004 : ClassDecl->hasTrivialCopyAssignment());
11006 // Note that we have added this copy-assignment operator.
11007 ++ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
11009 Scope *S = getScopeForContext(ClassDecl);
11010 CheckImplicitSpecialMemberDeclaration(S, CopyAssignment);
11012 if (ShouldDeleteSpecialMember(CopyAssignment, CXXCopyAssignment))
11013 SetDeclDeleted(CopyAssignment, ClassLoc);
11016 PushOnScopeChains(CopyAssignment, S, false);
11017 ClassDecl->addDecl(CopyAssignment);
11019 return CopyAssignment;
11022 /// Diagnose an implicit copy operation for a class which is odr-used, but
11023 /// which is deprecated because the class has a user-declared copy constructor,
11024 /// copy assignment operator, or destructor.
11025 static void diagnoseDeprecatedCopyOperation(Sema &S, CXXMethodDecl *CopyOp,
11026 SourceLocation UseLoc) {
11027 assert(CopyOp->isImplicit());
11029 CXXRecordDecl *RD = CopyOp->getParent();
11030 CXXMethodDecl *UserDeclaredOperation = nullptr;
11032 // In Microsoft mode, assignment operations don't affect constructors and
11034 if (RD->hasUserDeclaredDestructor()) {
11035 UserDeclaredOperation = RD->getDestructor();
11036 } else if (!isa<CXXConstructorDecl>(CopyOp) &&
11037 RD->hasUserDeclaredCopyConstructor() &&
11038 !S.getLangOpts().MSVCCompat) {
11039 // Find any user-declared copy constructor.
11040 for (auto *I : RD->ctors()) {
11041 if (I->isCopyConstructor()) {
11042 UserDeclaredOperation = I;
11046 assert(UserDeclaredOperation);
11047 } else if (isa<CXXConstructorDecl>(CopyOp) &&
11048 RD->hasUserDeclaredCopyAssignment() &&
11049 !S.getLangOpts().MSVCCompat) {
11050 // Find any user-declared move assignment operator.
11051 for (auto *I : RD->methods()) {
11052 if (I->isCopyAssignmentOperator()) {
11053 UserDeclaredOperation = I;
11057 assert(UserDeclaredOperation);
11060 if (UserDeclaredOperation) {
11061 S.Diag(UserDeclaredOperation->getLocation(),
11062 diag::warn_deprecated_copy_operation)
11063 << RD << /*copy assignment*/!isa<CXXConstructorDecl>(CopyOp)
11064 << /*destructor*/isa<CXXDestructorDecl>(UserDeclaredOperation);
11065 S.Diag(UseLoc, diag::note_member_synthesized_at)
11066 << (isa<CXXConstructorDecl>(CopyOp) ? Sema::CXXCopyConstructor
11067 : Sema::CXXCopyAssignment)
11072 void Sema::DefineImplicitCopyAssignment(SourceLocation CurrentLocation,
11073 CXXMethodDecl *CopyAssignOperator) {
11074 assert((CopyAssignOperator->isDefaulted() &&
11075 CopyAssignOperator->isOverloadedOperator() &&
11076 CopyAssignOperator->getOverloadedOperator() == OO_Equal &&
11077 !CopyAssignOperator->doesThisDeclarationHaveABody() &&
11078 !CopyAssignOperator->isDeleted()) &&
11079 "DefineImplicitCopyAssignment called for wrong function");
11081 CXXRecordDecl *ClassDecl = CopyAssignOperator->getParent();
11083 if (ClassDecl->isInvalidDecl() || CopyAssignOperator->isInvalidDecl()) {
11084 CopyAssignOperator->setInvalidDecl();
11088 // C++11 [class.copy]p18:
11089 // The [definition of an implicitly declared copy assignment operator] is
11090 // deprecated if the class has a user-declared copy constructor or a
11091 // user-declared destructor.
11092 if (getLangOpts().CPlusPlus11 && CopyAssignOperator->isImplicit())
11093 diagnoseDeprecatedCopyOperation(*this, CopyAssignOperator, CurrentLocation);
11095 CopyAssignOperator->markUsed(Context);
11097 SynthesizedFunctionScope Scope(*this, CopyAssignOperator);
11098 DiagnosticErrorTrap Trap(Diags);
11100 // C++0x [class.copy]p30:
11101 // The implicitly-defined or explicitly-defaulted copy assignment operator
11102 // for a non-union class X performs memberwise copy assignment of its
11103 // subobjects. The direct base classes of X are assigned first, in the
11104 // order of their declaration in the base-specifier-list, and then the
11105 // immediate non-static data members of X are assigned, in the order in
11106 // which they were declared in the class definition.
11108 // The statements that form the synthesized function body.
11109 SmallVector<Stmt*, 8> Statements;
11111 // The parameter for the "other" object, which we are copying from.
11112 ParmVarDecl *Other = CopyAssignOperator->getParamDecl(0);
11113 Qualifiers OtherQuals = Other->getType().getQualifiers();
11114 QualType OtherRefType = Other->getType();
11115 if (const LValueReferenceType *OtherRef
11116 = OtherRefType->getAs<LValueReferenceType>()) {
11117 OtherRefType = OtherRef->getPointeeType();
11118 OtherQuals = OtherRefType.getQualifiers();
11121 // Our location for everything implicitly-generated.
11122 SourceLocation Loc = CopyAssignOperator->getLocEnd().isValid()
11123 ? CopyAssignOperator->getLocEnd()
11124 : CopyAssignOperator->getLocation();
11126 // Builds a DeclRefExpr for the "other" object.
11127 RefBuilder OtherRef(Other, OtherRefType);
11129 // Builds the "this" pointer.
11132 // Assign base classes.
11133 bool Invalid = false;
11134 for (auto &Base : ClassDecl->bases()) {
11135 // Form the assignment:
11136 // static_cast<Base*>(this)->Base::operator=(static_cast<Base&>(other));
11137 QualType BaseType = Base.getType().getUnqualifiedType();
11138 if (!BaseType->isRecordType()) {
11143 CXXCastPath BasePath;
11144 BasePath.push_back(&Base);
11146 // Construct the "from" expression, which is an implicit cast to the
11147 // appropriately-qualified base type.
11148 CastBuilder From(OtherRef, Context.getQualifiedType(BaseType, OtherQuals),
11149 VK_LValue, BasePath);
11151 // Dereference "this".
11152 DerefBuilder DerefThis(This);
11153 CastBuilder To(DerefThis,
11154 Context.getCVRQualifiedType(
11155 BaseType, CopyAssignOperator->getTypeQualifiers()),
11156 VK_LValue, BasePath);
11159 StmtResult Copy = buildSingleCopyAssign(*this, Loc, BaseType,
11161 /*CopyingBaseSubobject=*/true,
11163 if (Copy.isInvalid()) {
11164 Diag(CurrentLocation, diag::note_member_synthesized_at)
11165 << CXXCopyAssignment << Context.getTagDeclType(ClassDecl);
11166 CopyAssignOperator->setInvalidDecl();
11170 // Success! Record the copy.
11171 Statements.push_back(Copy.getAs<Expr>());
11174 // Assign non-static members.
11175 for (auto *Field : ClassDecl->fields()) {
11176 // FIXME: We should form some kind of AST representation for the implied
11177 // memcpy in a union copy operation.
11178 if (Field->isUnnamedBitfield() || Field->getParent()->isUnion())
11181 if (Field->isInvalidDecl()) {
11186 // Check for members of reference type; we can't copy those.
11187 if (Field->getType()->isReferenceType()) {
11188 Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
11189 << Context.getTagDeclType(ClassDecl) << 0 << Field->getDeclName();
11190 Diag(Field->getLocation(), diag::note_declared_at);
11191 Diag(CurrentLocation, diag::note_member_synthesized_at)
11192 << CXXCopyAssignment << Context.getTagDeclType(ClassDecl);
11197 // Check for members of const-qualified, non-class type.
11198 QualType BaseType = Context.getBaseElementType(Field->getType());
11199 if (!BaseType->getAs<RecordType>() && BaseType.isConstQualified()) {
11200 Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
11201 << Context.getTagDeclType(ClassDecl) << 1 << Field->getDeclName();
11202 Diag(Field->getLocation(), diag::note_declared_at);
11203 Diag(CurrentLocation, diag::note_member_synthesized_at)
11204 << CXXCopyAssignment << Context.getTagDeclType(ClassDecl);
11209 // Suppress assigning zero-width bitfields.
11210 if (Field->isBitField() && Field->getBitWidthValue(Context) == 0)
11213 QualType FieldType = Field->getType().getNonReferenceType();
11214 if (FieldType->isIncompleteArrayType()) {
11215 assert(ClassDecl->hasFlexibleArrayMember() &&
11216 "Incomplete array type is not valid");
11220 // Build references to the field in the object we're copying from and to.
11221 CXXScopeSpec SS; // Intentionally empty
11222 LookupResult MemberLookup(*this, Field->getDeclName(), Loc,
11224 MemberLookup.addDecl(Field);
11225 MemberLookup.resolveKind();
11227 MemberBuilder From(OtherRef, OtherRefType, /*IsArrow=*/false, MemberLookup);
11229 MemberBuilder To(This, getCurrentThisType(), /*IsArrow=*/true, MemberLookup);
11231 // Build the copy of this field.
11232 StmtResult Copy = buildSingleCopyAssign(*this, Loc, FieldType,
11234 /*CopyingBaseSubobject=*/false,
11236 if (Copy.isInvalid()) {
11237 Diag(CurrentLocation, diag::note_member_synthesized_at)
11238 << CXXCopyAssignment << Context.getTagDeclType(ClassDecl);
11239 CopyAssignOperator->setInvalidDecl();
11243 // Success! Record the copy.
11244 Statements.push_back(Copy.getAs<Stmt>());
11248 // Add a "return *this;"
11249 ExprResult ThisObj = CreateBuiltinUnaryOp(Loc, UO_Deref, This.build(*this, Loc));
11251 StmtResult Return = BuildReturnStmt(Loc, ThisObj.get());
11252 if (Return.isInvalid())
11255 Statements.push_back(Return.getAs<Stmt>());
11257 if (Trap.hasErrorOccurred()) {
11258 Diag(CurrentLocation, diag::note_member_synthesized_at)
11259 << CXXCopyAssignment << Context.getTagDeclType(ClassDecl);
11265 // The exception specification is needed because we are defining the
11267 ResolveExceptionSpec(CurrentLocation,
11268 CopyAssignOperator->getType()->castAs<FunctionProtoType>());
11271 CopyAssignOperator->setInvalidDecl();
11277 CompoundScopeRAII CompoundScope(*this);
11278 Body = ActOnCompoundStmt(Loc, Loc, Statements,
11279 /*isStmtExpr=*/false);
11280 assert(!Body.isInvalid() && "Compound statement creation cannot fail");
11282 CopyAssignOperator->setBody(Body.getAs<Stmt>());
11284 if (ASTMutationListener *L = getASTMutationListener()) {
11285 L->CompletedImplicitDefinition(CopyAssignOperator);
11289 Sema::ImplicitExceptionSpecification
11290 Sema::ComputeDefaultedMoveAssignmentExceptionSpec(CXXMethodDecl *MD) {
11291 CXXRecordDecl *ClassDecl = MD->getParent();
11293 ImplicitExceptionSpecification ExceptSpec(*this);
11294 if (ClassDecl->isInvalidDecl())
11297 // C++0x [except.spec]p14:
11298 // An implicitly declared special member function (Clause 12) shall have an
11299 // exception-specification. [...]
11301 // It is unspecified whether or not an implicit move assignment operator
11302 // attempts to deduplicate calls to assignment operators of virtual bases are
11303 // made. As such, this exception specification is effectively unspecified.
11304 // Based on a similar decision made for constness in C++0x, we're erring on
11305 // the side of assuming such calls to be made regardless of whether they
11306 // actually happen.
11307 // Note that a move constructor is not implicitly declared when there are
11308 // virtual bases, but it can still be user-declared and explicitly defaulted.
11309 for (const auto &Base : ClassDecl->bases()) {
11310 if (Base.isVirtual())
11313 CXXRecordDecl *BaseClassDecl
11314 = cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
11315 if (CXXMethodDecl *MoveAssign = LookupMovingAssignment(BaseClassDecl,
11317 ExceptSpec.CalledDecl(Base.getLocStart(), MoveAssign);
11320 for (const auto &Base : ClassDecl->vbases()) {
11321 CXXRecordDecl *BaseClassDecl
11322 = cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
11323 if (CXXMethodDecl *MoveAssign = LookupMovingAssignment(BaseClassDecl,
11325 ExceptSpec.CalledDecl(Base.getLocStart(), MoveAssign);
11328 for (const auto *Field : ClassDecl->fields()) {
11329 QualType FieldType = Context.getBaseElementType(Field->getType());
11330 if (CXXRecordDecl *FieldClassDecl = FieldType->getAsCXXRecordDecl()) {
11331 if (CXXMethodDecl *MoveAssign =
11332 LookupMovingAssignment(FieldClassDecl,
11333 FieldType.getCVRQualifiers(),
11335 ExceptSpec.CalledDecl(Field->getLocation(), MoveAssign);
11342 CXXMethodDecl *Sema::DeclareImplicitMoveAssignment(CXXRecordDecl *ClassDecl) {
11343 assert(ClassDecl->needsImplicitMoveAssignment());
11345 DeclaringSpecialMember DSM(*this, ClassDecl, CXXMoveAssignment);
11346 if (DSM.isAlreadyBeingDeclared())
11349 // Note: The following rules are largely analoguous to the move
11350 // constructor rules.
11352 QualType ArgType = Context.getTypeDeclType(ClassDecl);
11353 QualType RetType = Context.getLValueReferenceType(ArgType);
11354 ArgType = Context.getRValueReferenceType(ArgType);
11356 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
11360 // An implicitly-declared move assignment operator is an inline public
11361 // member of its class.
11362 DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
11363 SourceLocation ClassLoc = ClassDecl->getLocation();
11364 DeclarationNameInfo NameInfo(Name, ClassLoc);
11365 CXXMethodDecl *MoveAssignment =
11366 CXXMethodDecl::Create(Context, ClassDecl, ClassLoc, NameInfo, QualType(),
11367 /*TInfo=*/nullptr, /*StorageClass=*/SC_None,
11368 /*isInline=*/true, Constexpr, SourceLocation());
11369 MoveAssignment->setAccess(AS_public);
11370 MoveAssignment->setDefaulted();
11371 MoveAssignment->setImplicit();
11373 if (getLangOpts().CUDA) {
11374 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXMoveAssignment,
11376 /* ConstRHS */ false,
11377 /* Diagnose */ false);
11380 // Build an exception specification pointing back at this member.
11381 FunctionProtoType::ExtProtoInfo EPI =
11382 getImplicitMethodEPI(*this, MoveAssignment);
11383 MoveAssignment->setType(Context.getFunctionType(RetType, ArgType, EPI));
11385 // Add the parameter to the operator.
11386 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, MoveAssignment,
11387 ClassLoc, ClassLoc,
11388 /*Id=*/nullptr, ArgType,
11389 /*TInfo=*/nullptr, SC_None,
11391 MoveAssignment->setParams(FromParam);
11393 MoveAssignment->setTrivial(
11394 ClassDecl->needsOverloadResolutionForMoveAssignment()
11395 ? SpecialMemberIsTrivial(MoveAssignment, CXXMoveAssignment)
11396 : ClassDecl->hasTrivialMoveAssignment());
11398 // Note that we have added this copy-assignment operator.
11399 ++ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
11401 Scope *S = getScopeForContext(ClassDecl);
11402 CheckImplicitSpecialMemberDeclaration(S, MoveAssignment);
11404 if (ShouldDeleteSpecialMember(MoveAssignment, CXXMoveAssignment)) {
11405 ClassDecl->setImplicitMoveAssignmentIsDeleted();
11406 SetDeclDeleted(MoveAssignment, ClassLoc);
11410 PushOnScopeChains(MoveAssignment, S, false);
11411 ClassDecl->addDecl(MoveAssignment);
11413 return MoveAssignment;
11416 /// Check if we're implicitly defining a move assignment operator for a class
11417 /// with virtual bases. Such a move assignment might move-assign the virtual
11418 /// base multiple times.
11419 static void checkMoveAssignmentForRepeatedMove(Sema &S, CXXRecordDecl *Class,
11420 SourceLocation CurrentLocation) {
11421 assert(!Class->isDependentContext() && "should not define dependent move");
11423 // Only a virtual base could get implicitly move-assigned multiple times.
11424 // Only a non-trivial move assignment can observe this. We only want to
11425 // diagnose if we implicitly define an assignment operator that assigns
11426 // two base classes, both of which move-assign the same virtual base.
11427 if (Class->getNumVBases() == 0 || Class->hasTrivialMoveAssignment() ||
11428 Class->getNumBases() < 2)
11431 llvm::SmallVector<CXXBaseSpecifier *, 16> Worklist;
11432 typedef llvm::DenseMap<CXXRecordDecl*, CXXBaseSpecifier*> VBaseMap;
11435 for (auto &BI : Class->bases()) {
11436 Worklist.push_back(&BI);
11437 while (!Worklist.empty()) {
11438 CXXBaseSpecifier *BaseSpec = Worklist.pop_back_val();
11439 CXXRecordDecl *Base = BaseSpec->getType()->getAsCXXRecordDecl();
11441 // If the base has no non-trivial move assignment operators,
11442 // we don't care about moves from it.
11443 if (!Base->hasNonTrivialMoveAssignment())
11446 // If there's nothing virtual here, skip it.
11447 if (!BaseSpec->isVirtual() && !Base->getNumVBases())
11450 // If we're not actually going to call a move assignment for this base,
11451 // or the selected move assignment is trivial, skip it.
11452 Sema::SpecialMemberOverloadResult *SMOR =
11453 S.LookupSpecialMember(Base, Sema::CXXMoveAssignment,
11454 /*ConstArg*/false, /*VolatileArg*/false,
11455 /*RValueThis*/true, /*ConstThis*/false,
11456 /*VolatileThis*/false);
11457 if (!SMOR->getMethod() || SMOR->getMethod()->isTrivial() ||
11458 !SMOR->getMethod()->isMoveAssignmentOperator())
11461 if (BaseSpec->isVirtual()) {
11462 // We're going to move-assign this virtual base, and its move
11463 // assignment operator is not trivial. If this can happen for
11464 // multiple distinct direct bases of Class, diagnose it. (If it
11465 // only happens in one base, we'll diagnose it when synthesizing
11466 // that base class's move assignment operator.)
11467 CXXBaseSpecifier *&Existing =
11468 VBases.insert(std::make_pair(Base->getCanonicalDecl(), &BI))
11470 if (Existing && Existing != &BI) {
11471 S.Diag(CurrentLocation, diag::warn_vbase_moved_multiple_times)
11473 S.Diag(Existing->getLocStart(), diag::note_vbase_moved_here)
11474 << (Base->getCanonicalDecl() ==
11475 Existing->getType()->getAsCXXRecordDecl()->getCanonicalDecl())
11476 << Base << Existing->getType() << Existing->getSourceRange();
11477 S.Diag(BI.getLocStart(), diag::note_vbase_moved_here)
11478 << (Base->getCanonicalDecl() ==
11479 BI.getType()->getAsCXXRecordDecl()->getCanonicalDecl())
11480 << Base << BI.getType() << BaseSpec->getSourceRange();
11482 // Only diagnose each vbase once.
11483 Existing = nullptr;
11486 // Only walk over bases that have defaulted move assignment operators.
11487 // We assume that any user-provided move assignment operator handles
11488 // the multiple-moves-of-vbase case itself somehow.
11489 if (!SMOR->getMethod()->isDefaulted())
11492 // We're going to move the base classes of Base. Add them to the list.
11493 for (auto &BI : Base->bases())
11494 Worklist.push_back(&BI);
11500 void Sema::DefineImplicitMoveAssignment(SourceLocation CurrentLocation,
11501 CXXMethodDecl *MoveAssignOperator) {
11502 assert((MoveAssignOperator->isDefaulted() &&
11503 MoveAssignOperator->isOverloadedOperator() &&
11504 MoveAssignOperator->getOverloadedOperator() == OO_Equal &&
11505 !MoveAssignOperator->doesThisDeclarationHaveABody() &&
11506 !MoveAssignOperator->isDeleted()) &&
11507 "DefineImplicitMoveAssignment called for wrong function");
11509 CXXRecordDecl *ClassDecl = MoveAssignOperator->getParent();
11511 if (ClassDecl->isInvalidDecl() || MoveAssignOperator->isInvalidDecl()) {
11512 MoveAssignOperator->setInvalidDecl();
11516 MoveAssignOperator->markUsed(Context);
11518 SynthesizedFunctionScope Scope(*this, MoveAssignOperator);
11519 DiagnosticErrorTrap Trap(Diags);
11521 // C++0x [class.copy]p28:
11522 // The implicitly-defined or move assignment operator for a non-union class
11523 // X performs memberwise move assignment of its subobjects. The direct base
11524 // classes of X are assigned first, in the order of their declaration in the
11525 // base-specifier-list, and then the immediate non-static data members of X
11526 // are assigned, in the order in which they were declared in the class
11529 // Issue a warning if our implicit move assignment operator will move
11530 // from a virtual base more than once.
11531 checkMoveAssignmentForRepeatedMove(*this, ClassDecl, CurrentLocation);
11533 // The statements that form the synthesized function body.
11534 SmallVector<Stmt*, 8> Statements;
11536 // The parameter for the "other" object, which we are move from.
11537 ParmVarDecl *Other = MoveAssignOperator->getParamDecl(0);
11538 QualType OtherRefType = Other->getType()->
11539 getAs<RValueReferenceType>()->getPointeeType();
11540 assert(!OtherRefType.getQualifiers() &&
11541 "Bad argument type of defaulted move assignment");
11543 // Our location for everything implicitly-generated.
11544 SourceLocation Loc = MoveAssignOperator->getLocEnd().isValid()
11545 ? MoveAssignOperator->getLocEnd()
11546 : MoveAssignOperator->getLocation();
11548 // Builds a reference to the "other" object.
11549 RefBuilder OtherRef(Other, OtherRefType);
11551 MoveCastBuilder MoveOther(OtherRef);
11553 // Builds the "this" pointer.
11556 // Assign base classes.
11557 bool Invalid = false;
11558 for (auto &Base : ClassDecl->bases()) {
11559 // C++11 [class.copy]p28:
11560 // It is unspecified whether subobjects representing virtual base classes
11561 // are assigned more than once by the implicitly-defined copy assignment
11563 // FIXME: Do not assign to a vbase that will be assigned by some other base
11564 // class. For a move-assignment, this can result in the vbase being moved
11567 // Form the assignment:
11568 // static_cast<Base*>(this)->Base::operator=(static_cast<Base&&>(other));
11569 QualType BaseType = Base.getType().getUnqualifiedType();
11570 if (!BaseType->isRecordType()) {
11575 CXXCastPath BasePath;
11576 BasePath.push_back(&Base);
11578 // Construct the "from" expression, which is an implicit cast to the
11579 // appropriately-qualified base type.
11580 CastBuilder From(OtherRef, BaseType, VK_XValue, BasePath);
11582 // Dereference "this".
11583 DerefBuilder DerefThis(This);
11585 // Implicitly cast "this" to the appropriately-qualified base type.
11586 CastBuilder To(DerefThis,
11587 Context.getCVRQualifiedType(
11588 BaseType, MoveAssignOperator->getTypeQualifiers()),
11589 VK_LValue, BasePath);
11592 StmtResult Move = buildSingleCopyAssign(*this, Loc, BaseType,
11594 /*CopyingBaseSubobject=*/true,
11595 /*Copying=*/false);
11596 if (Move.isInvalid()) {
11597 Diag(CurrentLocation, diag::note_member_synthesized_at)
11598 << CXXMoveAssignment << Context.getTagDeclType(ClassDecl);
11599 MoveAssignOperator->setInvalidDecl();
11603 // Success! Record the move.
11604 Statements.push_back(Move.getAs<Expr>());
11607 // Assign non-static members.
11608 for (auto *Field : ClassDecl->fields()) {
11609 // FIXME: We should form some kind of AST representation for the implied
11610 // memcpy in a union copy operation.
11611 if (Field->isUnnamedBitfield() || Field->getParent()->isUnion())
11614 if (Field->isInvalidDecl()) {
11619 // Check for members of reference type; we can't move those.
11620 if (Field->getType()->isReferenceType()) {
11621 Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
11622 << Context.getTagDeclType(ClassDecl) << 0 << Field->getDeclName();
11623 Diag(Field->getLocation(), diag::note_declared_at);
11624 Diag(CurrentLocation, diag::note_member_synthesized_at)
11625 << CXXMoveAssignment << Context.getTagDeclType(ClassDecl);
11630 // Check for members of const-qualified, non-class type.
11631 QualType BaseType = Context.getBaseElementType(Field->getType());
11632 if (!BaseType->getAs<RecordType>() && BaseType.isConstQualified()) {
11633 Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
11634 << Context.getTagDeclType(ClassDecl) << 1 << Field->getDeclName();
11635 Diag(Field->getLocation(), diag::note_declared_at);
11636 Diag(CurrentLocation, diag::note_member_synthesized_at)
11637 << CXXMoveAssignment << Context.getTagDeclType(ClassDecl);
11642 // Suppress assigning zero-width bitfields.
11643 if (Field->isBitField() && Field->getBitWidthValue(Context) == 0)
11646 QualType FieldType = Field->getType().getNonReferenceType();
11647 if (FieldType->isIncompleteArrayType()) {
11648 assert(ClassDecl->hasFlexibleArrayMember() &&
11649 "Incomplete array type is not valid");
11653 // Build references to the field in the object we're copying from and to.
11654 LookupResult MemberLookup(*this, Field->getDeclName(), Loc,
11656 MemberLookup.addDecl(Field);
11657 MemberLookup.resolveKind();
11658 MemberBuilder From(MoveOther, OtherRefType,
11659 /*IsArrow=*/false, MemberLookup);
11660 MemberBuilder To(This, getCurrentThisType(),
11661 /*IsArrow=*/true, MemberLookup);
11663 assert(!From.build(*this, Loc)->isLValue() && // could be xvalue or prvalue
11664 "Member reference with rvalue base must be rvalue except for reference "
11665 "members, which aren't allowed for move assignment.");
11667 // Build the move of this field.
11668 StmtResult Move = buildSingleCopyAssign(*this, Loc, FieldType,
11670 /*CopyingBaseSubobject=*/false,
11671 /*Copying=*/false);
11672 if (Move.isInvalid()) {
11673 Diag(CurrentLocation, diag::note_member_synthesized_at)
11674 << CXXMoveAssignment << Context.getTagDeclType(ClassDecl);
11675 MoveAssignOperator->setInvalidDecl();
11679 // Success! Record the copy.
11680 Statements.push_back(Move.getAs<Stmt>());
11684 // Add a "return *this;"
11685 ExprResult ThisObj =
11686 CreateBuiltinUnaryOp(Loc, UO_Deref, This.build(*this, Loc));
11688 StmtResult Return = BuildReturnStmt(Loc, ThisObj.get());
11689 if (Return.isInvalid())
11692 Statements.push_back(Return.getAs<Stmt>());
11694 if (Trap.hasErrorOccurred()) {
11695 Diag(CurrentLocation, diag::note_member_synthesized_at)
11696 << CXXMoveAssignment << Context.getTagDeclType(ClassDecl);
11702 // The exception specification is needed because we are defining the
11704 ResolveExceptionSpec(CurrentLocation,
11705 MoveAssignOperator->getType()->castAs<FunctionProtoType>());
11708 MoveAssignOperator->setInvalidDecl();
11714 CompoundScopeRAII CompoundScope(*this);
11715 Body = ActOnCompoundStmt(Loc, Loc, Statements,
11716 /*isStmtExpr=*/false);
11717 assert(!Body.isInvalid() && "Compound statement creation cannot fail");
11719 MoveAssignOperator->setBody(Body.getAs<Stmt>());
11721 if (ASTMutationListener *L = getASTMutationListener()) {
11722 L->CompletedImplicitDefinition(MoveAssignOperator);
11726 Sema::ImplicitExceptionSpecification
11727 Sema::ComputeDefaultedCopyCtorExceptionSpec(CXXMethodDecl *MD) {
11728 CXXRecordDecl *ClassDecl = MD->getParent();
11730 ImplicitExceptionSpecification ExceptSpec(*this);
11731 if (ClassDecl->isInvalidDecl())
11734 const FunctionProtoType *T = MD->getType()->castAs<FunctionProtoType>();
11735 assert(T->getNumParams() >= 1 && "not a copy ctor");
11736 unsigned Quals = T->getParamType(0).getNonReferenceType().getCVRQualifiers();
11738 // C++ [except.spec]p14:
11739 // An implicitly declared special member function (Clause 12) shall have an
11740 // exception-specification. [...]
11741 for (const auto &Base : ClassDecl->bases()) {
11742 // Virtual bases are handled below.
11743 if (Base.isVirtual())
11746 CXXRecordDecl *BaseClassDecl
11747 = cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
11748 if (CXXConstructorDecl *CopyConstructor =
11749 LookupCopyingConstructor(BaseClassDecl, Quals))
11750 ExceptSpec.CalledDecl(Base.getLocStart(), CopyConstructor);
11752 for (const auto &Base : ClassDecl->vbases()) {
11753 CXXRecordDecl *BaseClassDecl
11754 = cast<CXXRecordDecl>(Base.getType()->getAs<RecordType>()->getDecl());
11755 if (CXXConstructorDecl *CopyConstructor =
11756 LookupCopyingConstructor(BaseClassDecl, Quals))
11757 ExceptSpec.CalledDecl(Base.getLocStart(), CopyConstructor);
11759 for (const auto *Field : ClassDecl->fields()) {
11760 QualType FieldType = Context.getBaseElementType(Field->getType());
11761 if (CXXRecordDecl *FieldClassDecl = FieldType->getAsCXXRecordDecl()) {
11762 if (CXXConstructorDecl *CopyConstructor =
11763 LookupCopyingConstructor(FieldClassDecl,
11764 Quals | FieldType.getCVRQualifiers()))
11765 ExceptSpec.CalledDecl(Field->getLocation(), CopyConstructor);
11772 CXXConstructorDecl *Sema::DeclareImplicitCopyConstructor(
11773 CXXRecordDecl *ClassDecl) {
11774 // C++ [class.copy]p4:
11775 // If the class definition does not explicitly declare a copy
11776 // constructor, one is declared implicitly.
11777 assert(ClassDecl->needsImplicitCopyConstructor());
11779 DeclaringSpecialMember DSM(*this, ClassDecl, CXXCopyConstructor);
11780 if (DSM.isAlreadyBeingDeclared())
11783 QualType ClassType = Context.getTypeDeclType(ClassDecl);
11784 QualType ArgType = ClassType;
11785 bool Const = ClassDecl->implicitCopyConstructorHasConstParam();
11787 ArgType = ArgType.withConst();
11788 ArgType = Context.getLValueReferenceType(ArgType);
11790 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
11791 CXXCopyConstructor,
11794 DeclarationName Name
11795 = Context.DeclarationNames.getCXXConstructorName(
11796 Context.getCanonicalType(ClassType));
11797 SourceLocation ClassLoc = ClassDecl->getLocation();
11798 DeclarationNameInfo NameInfo(Name, ClassLoc);
11800 // An implicitly-declared copy constructor is an inline public
11801 // member of its class.
11802 CXXConstructorDecl *CopyConstructor = CXXConstructorDecl::Create(
11803 Context, ClassDecl, ClassLoc, NameInfo, QualType(), /*TInfo=*/nullptr,
11804 /*isExplicit=*/false, /*isInline=*/true, /*isImplicitlyDeclared=*/true,
11806 CopyConstructor->setAccess(AS_public);
11807 CopyConstructor->setDefaulted();
11809 if (getLangOpts().CUDA) {
11810 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXCopyConstructor,
11812 /* ConstRHS */ Const,
11813 /* Diagnose */ false);
11816 // Build an exception specification pointing back at this member.
11817 FunctionProtoType::ExtProtoInfo EPI =
11818 getImplicitMethodEPI(*this, CopyConstructor);
11819 CopyConstructor->setType(
11820 Context.getFunctionType(Context.VoidTy, ArgType, EPI));
11822 // Add the parameter to the constructor.
11823 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor,
11824 ClassLoc, ClassLoc,
11825 /*IdentifierInfo=*/nullptr,
11826 ArgType, /*TInfo=*/nullptr,
11828 CopyConstructor->setParams(FromParam);
11830 CopyConstructor->setTrivial(
11831 ClassDecl->needsOverloadResolutionForCopyConstructor()
11832 ? SpecialMemberIsTrivial(CopyConstructor, CXXCopyConstructor)
11833 : ClassDecl->hasTrivialCopyConstructor());
11835 // Note that we have declared this constructor.
11836 ++ASTContext::NumImplicitCopyConstructorsDeclared;
11838 Scope *S = getScopeForContext(ClassDecl);
11839 CheckImplicitSpecialMemberDeclaration(S, CopyConstructor);
11841 if (ShouldDeleteSpecialMember(CopyConstructor, CXXCopyConstructor))
11842 SetDeclDeleted(CopyConstructor, ClassLoc);
11845 PushOnScopeChains(CopyConstructor, S, false);
11846 ClassDecl->addDecl(CopyConstructor);
11848 return CopyConstructor;
11851 void Sema::DefineImplicitCopyConstructor(SourceLocation CurrentLocation,
11852 CXXConstructorDecl *CopyConstructor) {
11853 assert((CopyConstructor->isDefaulted() &&
11854 CopyConstructor->isCopyConstructor() &&
11855 !CopyConstructor->doesThisDeclarationHaveABody() &&
11856 !CopyConstructor->isDeleted()) &&
11857 "DefineImplicitCopyConstructor - call it for implicit copy ctor");
11859 CXXRecordDecl *ClassDecl = CopyConstructor->getParent();
11860 assert(ClassDecl && "DefineImplicitCopyConstructor - invalid constructor");
11862 // C++11 [class.copy]p7:
11863 // The [definition of an implicitly declared copy constructor] is
11864 // deprecated if the class has a user-declared copy assignment operator
11865 // or a user-declared destructor.
11866 if (getLangOpts().CPlusPlus11 && CopyConstructor->isImplicit())
11867 diagnoseDeprecatedCopyOperation(*this, CopyConstructor, CurrentLocation);
11869 SynthesizedFunctionScope Scope(*this, CopyConstructor);
11870 DiagnosticErrorTrap Trap(Diags);
11872 if (SetCtorInitializers(CopyConstructor, /*AnyErrors=*/false) ||
11873 Trap.hasErrorOccurred()) {
11874 Diag(CurrentLocation, diag::note_member_synthesized_at)
11875 << CXXCopyConstructor << Context.getTagDeclType(ClassDecl);
11876 CopyConstructor->setInvalidDecl();
11878 SourceLocation Loc = CopyConstructor->getLocEnd().isValid()
11879 ? CopyConstructor->getLocEnd()
11880 : CopyConstructor->getLocation();
11881 Sema::CompoundScopeRAII CompoundScope(*this);
11882 CopyConstructor->setBody(
11883 ActOnCompoundStmt(Loc, Loc, None, /*isStmtExpr=*/false).getAs<Stmt>());
11886 // The exception specification is needed because we are defining the
11888 ResolveExceptionSpec(CurrentLocation,
11889 CopyConstructor->getType()->castAs<FunctionProtoType>());
11891 CopyConstructor->markUsed(Context);
11892 MarkVTableUsed(CurrentLocation, ClassDecl);
11894 if (ASTMutationListener *L = getASTMutationListener()) {
11895 L->CompletedImplicitDefinition(CopyConstructor);
11899 Sema::ImplicitExceptionSpecification
11900 Sema::ComputeDefaultedMoveCtorExceptionSpec(CXXMethodDecl *MD) {
11901 CXXRecordDecl *ClassDecl = MD->getParent();
11903 // C++ [except.spec]p14:
11904 // An implicitly declared special member function (Clause 12) shall have an
11905 // exception-specification. [...]
11906 ImplicitExceptionSpecification ExceptSpec(*this);
11907 if (ClassDecl->isInvalidDecl())
11910 // Direct base-class constructors.
11911 for (const auto &B : ClassDecl->bases()) {
11912 if (B.isVirtual()) // Handled below.
11915 if (const RecordType *BaseType = B.getType()->getAs<RecordType>()) {
11916 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
11917 CXXConstructorDecl *Constructor =
11918 LookupMovingConstructor(BaseClassDecl, 0);
11919 // If this is a deleted function, add it anyway. This might be conformant
11920 // with the standard. This might not. I'm not sure. It might not matter.
11922 ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
11926 // Virtual base-class constructors.
11927 for (const auto &B : ClassDecl->vbases()) {
11928 if (const RecordType *BaseType = B.getType()->getAs<RecordType>()) {
11929 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
11930 CXXConstructorDecl *Constructor =
11931 LookupMovingConstructor(BaseClassDecl, 0);
11932 // If this is a deleted function, add it anyway. This might be conformant
11933 // with the standard. This might not. I'm not sure. It might not matter.
11935 ExceptSpec.CalledDecl(B.getLocStart(), Constructor);
11939 // Field constructors.
11940 for (const auto *F : ClassDecl->fields()) {
11941 QualType FieldType = Context.getBaseElementType(F->getType());
11942 if (CXXRecordDecl *FieldRecDecl = FieldType->getAsCXXRecordDecl()) {
11943 CXXConstructorDecl *Constructor =
11944 LookupMovingConstructor(FieldRecDecl, FieldType.getCVRQualifiers());
11945 // If this is a deleted function, add it anyway. This might be conformant
11946 // with the standard. This might not. I'm not sure. It might not matter.
11947 // In particular, the problem is that this function never gets called. It
11948 // might just be ill-formed because this function attempts to refer to
11949 // a deleted function here.
11951 ExceptSpec.CalledDecl(F->getLocation(), Constructor);
11958 CXXConstructorDecl *Sema::DeclareImplicitMoveConstructor(
11959 CXXRecordDecl *ClassDecl) {
11960 assert(ClassDecl->needsImplicitMoveConstructor());
11962 DeclaringSpecialMember DSM(*this, ClassDecl, CXXMoveConstructor);
11963 if (DSM.isAlreadyBeingDeclared())
11966 QualType ClassType = Context.getTypeDeclType(ClassDecl);
11967 QualType ArgType = Context.getRValueReferenceType(ClassType);
11969 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
11970 CXXMoveConstructor,
11973 DeclarationName Name
11974 = Context.DeclarationNames.getCXXConstructorName(
11975 Context.getCanonicalType(ClassType));
11976 SourceLocation ClassLoc = ClassDecl->getLocation();
11977 DeclarationNameInfo NameInfo(Name, ClassLoc);
11979 // C++11 [class.copy]p11:
11980 // An implicitly-declared copy/move constructor is an inline public
11981 // member of its class.
11982 CXXConstructorDecl *MoveConstructor = CXXConstructorDecl::Create(
11983 Context, ClassDecl, ClassLoc, NameInfo, QualType(), /*TInfo=*/nullptr,
11984 /*isExplicit=*/false, /*isInline=*/true, /*isImplicitlyDeclared=*/true,
11986 MoveConstructor->setAccess(AS_public);
11987 MoveConstructor->setDefaulted();
11989 if (getLangOpts().CUDA) {
11990 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXMoveConstructor,
11992 /* ConstRHS */ false,
11993 /* Diagnose */ false);
11996 // Build an exception specification pointing back at this member.
11997 FunctionProtoType::ExtProtoInfo EPI =
11998 getImplicitMethodEPI(*this, MoveConstructor);
11999 MoveConstructor->setType(
12000 Context.getFunctionType(Context.VoidTy, ArgType, EPI));
12002 // Add the parameter to the constructor.
12003 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, MoveConstructor,
12004 ClassLoc, ClassLoc,
12005 /*IdentifierInfo=*/nullptr,
12006 ArgType, /*TInfo=*/nullptr,
12008 MoveConstructor->setParams(FromParam);
12010 MoveConstructor->setTrivial(
12011 ClassDecl->needsOverloadResolutionForMoveConstructor()
12012 ? SpecialMemberIsTrivial(MoveConstructor, CXXMoveConstructor)
12013 : ClassDecl->hasTrivialMoveConstructor());
12015 // Note that we have declared this constructor.
12016 ++ASTContext::NumImplicitMoveConstructorsDeclared;
12018 Scope *S = getScopeForContext(ClassDecl);
12019 CheckImplicitSpecialMemberDeclaration(S, MoveConstructor);
12021 if (ShouldDeleteSpecialMember(MoveConstructor, CXXMoveConstructor)) {
12022 ClassDecl->setImplicitMoveConstructorIsDeleted();
12023 SetDeclDeleted(MoveConstructor, ClassLoc);
12027 PushOnScopeChains(MoveConstructor, S, false);
12028 ClassDecl->addDecl(MoveConstructor);
12030 return MoveConstructor;
12033 void Sema::DefineImplicitMoveConstructor(SourceLocation CurrentLocation,
12034 CXXConstructorDecl *MoveConstructor) {
12035 assert((MoveConstructor->isDefaulted() &&
12036 MoveConstructor->isMoveConstructor() &&
12037 !MoveConstructor->doesThisDeclarationHaveABody() &&
12038 !MoveConstructor->isDeleted()) &&
12039 "DefineImplicitMoveConstructor - call it for implicit move ctor");
12041 CXXRecordDecl *ClassDecl = MoveConstructor->getParent();
12042 assert(ClassDecl && "DefineImplicitMoveConstructor - invalid constructor");
12044 SynthesizedFunctionScope Scope(*this, MoveConstructor);
12045 DiagnosticErrorTrap Trap(Diags);
12047 if (SetCtorInitializers(MoveConstructor, /*AnyErrors=*/false) ||
12048 Trap.hasErrorOccurred()) {
12049 Diag(CurrentLocation, diag::note_member_synthesized_at)
12050 << CXXMoveConstructor << Context.getTagDeclType(ClassDecl);
12051 MoveConstructor->setInvalidDecl();
12053 SourceLocation Loc = MoveConstructor->getLocEnd().isValid()
12054 ? MoveConstructor->getLocEnd()
12055 : MoveConstructor->getLocation();
12056 Sema::CompoundScopeRAII CompoundScope(*this);
12057 MoveConstructor->setBody(ActOnCompoundStmt(
12058 Loc, Loc, None, /*isStmtExpr=*/ false).getAs<Stmt>());
12061 // The exception specification is needed because we are defining the
12063 ResolveExceptionSpec(CurrentLocation,
12064 MoveConstructor->getType()->castAs<FunctionProtoType>());
12066 MoveConstructor->markUsed(Context);
12067 MarkVTableUsed(CurrentLocation, ClassDecl);
12069 if (ASTMutationListener *L = getASTMutationListener()) {
12070 L->CompletedImplicitDefinition(MoveConstructor);
12074 bool Sema::isImplicitlyDeleted(FunctionDecl *FD) {
12075 return FD->isDeleted() && FD->isDefaulted() && isa<CXXMethodDecl>(FD);
12078 void Sema::DefineImplicitLambdaToFunctionPointerConversion(
12079 SourceLocation CurrentLocation,
12080 CXXConversionDecl *Conv) {
12081 CXXRecordDecl *Lambda = Conv->getParent();
12082 CXXMethodDecl *CallOp = Lambda->getLambdaCallOperator();
12083 // If we are defining a specialization of a conversion to function-ptr
12084 // cache the deduced template arguments for this specialization
12085 // so that we can use them to retrieve the corresponding call-operator
12086 // and static-invoker.
12087 const TemplateArgumentList *DeducedTemplateArgs = nullptr;
12089 // Retrieve the corresponding call-operator specialization.
12090 if (Lambda->isGenericLambda()) {
12091 assert(Conv->isFunctionTemplateSpecialization());
12092 FunctionTemplateDecl *CallOpTemplate =
12093 CallOp->getDescribedFunctionTemplate();
12094 DeducedTemplateArgs = Conv->getTemplateSpecializationArgs();
12095 void *InsertPos = nullptr;
12096 FunctionDecl *CallOpSpec = CallOpTemplate->findSpecialization(
12097 DeducedTemplateArgs->asArray(),
12099 assert(CallOpSpec &&
12100 "Conversion operator must have a corresponding call operator");
12101 CallOp = cast<CXXMethodDecl>(CallOpSpec);
12103 // Mark the call operator referenced (and add to pending instantiations
12105 // For both the conversion and static-invoker template specializations
12106 // we construct their body's in this function, so no need to add them
12107 // to the PendingInstantiations.
12108 MarkFunctionReferenced(CurrentLocation, CallOp);
12110 SynthesizedFunctionScope Scope(*this, Conv);
12111 DiagnosticErrorTrap Trap(Diags);
12113 // Retrieve the static invoker...
12114 CXXMethodDecl *Invoker = Lambda->getLambdaStaticInvoker();
12115 // ... and get the corresponding specialization for a generic lambda.
12116 if (Lambda->isGenericLambda()) {
12117 assert(DeducedTemplateArgs &&
12118 "Must have deduced template arguments from Conversion Operator");
12119 FunctionTemplateDecl *InvokeTemplate =
12120 Invoker->getDescribedFunctionTemplate();
12121 void *InsertPos = nullptr;
12122 FunctionDecl *InvokeSpec = InvokeTemplate->findSpecialization(
12123 DeducedTemplateArgs->asArray(),
12125 assert(InvokeSpec &&
12126 "Must have a corresponding static invoker specialization");
12127 Invoker = cast<CXXMethodDecl>(InvokeSpec);
12129 // Construct the body of the conversion function { return __invoke; }.
12130 Expr *FunctionRef = BuildDeclRefExpr(Invoker, Invoker->getType(),
12131 VK_LValue, Conv->getLocation()).get();
12132 assert(FunctionRef && "Can't refer to __invoke function?");
12133 Stmt *Return = BuildReturnStmt(Conv->getLocation(), FunctionRef).get();
12134 Conv->setBody(new (Context) CompoundStmt(Context, Return,
12135 Conv->getLocation(),
12136 Conv->getLocation()));
12138 Conv->markUsed(Context);
12139 Conv->setReferenced();
12141 // Fill in the __invoke function with a dummy implementation. IR generation
12142 // will fill in the actual details.
12143 Invoker->markUsed(Context);
12144 Invoker->setReferenced();
12145 Invoker->setBody(new (Context) CompoundStmt(Conv->getLocation()));
12147 if (ASTMutationListener *L = getASTMutationListener()) {
12148 L->CompletedImplicitDefinition(Conv);
12149 L->CompletedImplicitDefinition(Invoker);
12155 void Sema::DefineImplicitLambdaToBlockPointerConversion(
12156 SourceLocation CurrentLocation,
12157 CXXConversionDecl *Conv)
12159 assert(!Conv->getParent()->isGenericLambda());
12161 Conv->markUsed(Context);
12163 SynthesizedFunctionScope Scope(*this, Conv);
12164 DiagnosticErrorTrap Trap(Diags);
12166 // Copy-initialize the lambda object as needed to capture it.
12167 Expr *This = ActOnCXXThis(CurrentLocation).get();
12168 Expr *DerefThis =CreateBuiltinUnaryOp(CurrentLocation, UO_Deref, This).get();
12170 ExprResult BuildBlock = BuildBlockForLambdaConversion(CurrentLocation,
12171 Conv->getLocation(),
12174 // If we're not under ARC, make sure we still get the _Block_copy/autorelease
12175 // behavior. Note that only the general conversion function does this
12176 // (since it's unusable otherwise); in the case where we inline the
12177 // block literal, it has block literal lifetime semantics.
12178 if (!BuildBlock.isInvalid() && !getLangOpts().ObjCAutoRefCount)
12179 BuildBlock = ImplicitCastExpr::Create(Context, BuildBlock.get()->getType(),
12180 CK_CopyAndAutoreleaseBlockObject,
12181 BuildBlock.get(), nullptr, VK_RValue);
12183 if (BuildBlock.isInvalid()) {
12184 Diag(CurrentLocation, diag::note_lambda_to_block_conv);
12185 Conv->setInvalidDecl();
12189 // Create the return statement that returns the block from the conversion
12191 StmtResult Return = BuildReturnStmt(Conv->getLocation(), BuildBlock.get());
12192 if (Return.isInvalid()) {
12193 Diag(CurrentLocation, diag::note_lambda_to_block_conv);
12194 Conv->setInvalidDecl();
12198 // Set the body of the conversion function.
12199 Stmt *ReturnS = Return.get();
12200 Conv->setBody(new (Context) CompoundStmt(Context, ReturnS,
12201 Conv->getLocation(),
12202 Conv->getLocation()));
12204 // We're done; notify the mutation listener, if any.
12205 if (ASTMutationListener *L = getASTMutationListener()) {
12206 L->CompletedImplicitDefinition(Conv);
12210 /// \brief Determine whether the given list arguments contains exactly one
12211 /// "real" (non-default) argument.
12212 static bool hasOneRealArgument(MultiExprArg Args) {
12213 switch (Args.size()) {
12218 if (!Args[1]->isDefaultArgument())
12223 return !Args[0]->isDefaultArgument();
12230 Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
12231 NamedDecl *FoundDecl,
12232 CXXConstructorDecl *Constructor,
12233 MultiExprArg ExprArgs,
12234 bool HadMultipleCandidates,
12235 bool IsListInitialization,
12236 bool IsStdInitListInitialization,
12237 bool RequiresZeroInit,
12238 unsigned ConstructKind,
12239 SourceRange ParenRange) {
12240 bool Elidable = false;
12242 // C++0x [class.copy]p34:
12243 // When certain criteria are met, an implementation is allowed to
12244 // omit the copy/move construction of a class object, even if the
12245 // copy/move constructor and/or destructor for the object have
12246 // side effects. [...]
12247 // - when a temporary class object that has not been bound to a
12248 // reference (12.2) would be copied/moved to a class object
12249 // with the same cv-unqualified type, the copy/move operation
12250 // can be omitted by constructing the temporary object
12251 // directly into the target of the omitted copy/move
12252 if (ConstructKind == CXXConstructExpr::CK_Complete && Constructor &&
12253 Constructor->isCopyOrMoveConstructor() && hasOneRealArgument(ExprArgs)) {
12254 Expr *SubExpr = ExprArgs[0];
12255 Elidable = SubExpr->isTemporaryObject(
12256 Context, cast<CXXRecordDecl>(FoundDecl->getDeclContext()));
12259 return BuildCXXConstructExpr(ConstructLoc, DeclInitType,
12260 FoundDecl, Constructor,
12261 Elidable, ExprArgs, HadMultipleCandidates,
12262 IsListInitialization,
12263 IsStdInitListInitialization, RequiresZeroInit,
12264 ConstructKind, ParenRange);
12268 Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
12269 NamedDecl *FoundDecl,
12270 CXXConstructorDecl *Constructor,
12272 MultiExprArg ExprArgs,
12273 bool HadMultipleCandidates,
12274 bool IsListInitialization,
12275 bool IsStdInitListInitialization,
12276 bool RequiresZeroInit,
12277 unsigned ConstructKind,
12278 SourceRange ParenRange) {
12279 if (auto *Shadow = dyn_cast<ConstructorUsingShadowDecl>(FoundDecl)) {
12280 Constructor = findInheritingConstructor(ConstructLoc, Constructor, Shadow);
12281 if (DiagnoseUseOfDecl(Constructor, ConstructLoc))
12282 return ExprError();
12285 return BuildCXXConstructExpr(
12286 ConstructLoc, DeclInitType, Constructor, Elidable, ExprArgs,
12287 HadMultipleCandidates, IsListInitialization, IsStdInitListInitialization,
12288 RequiresZeroInit, ConstructKind, ParenRange);
12291 /// BuildCXXConstructExpr - Creates a complete call to a constructor,
12292 /// including handling of its default argument expressions.
12294 Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
12295 CXXConstructorDecl *Constructor,
12297 MultiExprArg ExprArgs,
12298 bool HadMultipleCandidates,
12299 bool IsListInitialization,
12300 bool IsStdInitListInitialization,
12301 bool RequiresZeroInit,
12302 unsigned ConstructKind,
12303 SourceRange ParenRange) {
12304 assert(declaresSameEntity(
12305 Constructor->getParent(),
12306 DeclInitType->getBaseElementTypeUnsafe()->getAsCXXRecordDecl()) &&
12307 "given constructor for wrong type");
12308 MarkFunctionReferenced(ConstructLoc, Constructor);
12309 if (getLangOpts().CUDA && !CheckCUDACall(ConstructLoc, Constructor))
12310 return ExprError();
12312 return CXXConstructExpr::Create(
12313 Context, DeclInitType, ConstructLoc, Constructor, Elidable,
12314 ExprArgs, HadMultipleCandidates, IsListInitialization,
12315 IsStdInitListInitialization, RequiresZeroInit,
12316 static_cast<CXXConstructExpr::ConstructionKind>(ConstructKind),
12320 ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
12321 assert(Field->hasInClassInitializer());
12323 // If we already have the in-class initializer nothing needs to be done.
12324 if (Field->getInClassInitializer())
12325 return CXXDefaultInitExpr::Create(Context, Loc, Field);
12327 // If we might have already tried and failed to instantiate, don't try again.
12328 if (Field->isInvalidDecl())
12329 return ExprError();
12331 // Maybe we haven't instantiated the in-class initializer. Go check the
12332 // pattern FieldDecl to see if it has one.
12333 CXXRecordDecl *ParentRD = cast<CXXRecordDecl>(Field->getParent());
12335 if (isTemplateInstantiation(ParentRD->getTemplateSpecializationKind())) {
12336 CXXRecordDecl *ClassPattern = ParentRD->getTemplateInstantiationPattern();
12337 DeclContext::lookup_result Lookup =
12338 ClassPattern->lookup(Field->getDeclName());
12340 // Lookup can return at most two results: the pattern for the field, or the
12341 // injected class name of the parent record. No other member can have the
12342 // same name as the field.
12343 // In modules mode, lookup can return multiple results (coming from
12344 // different modules).
12345 assert((getLangOpts().Modules || (!Lookup.empty() && Lookup.size() <= 2)) &&
12346 "more than two lookup results for field name");
12347 FieldDecl *Pattern = dyn_cast<FieldDecl>(Lookup[0]);
12349 assert(isa<CXXRecordDecl>(Lookup[0]) &&
12350 "cannot have other non-field member with same name");
12351 for (auto L : Lookup)
12352 if (isa<FieldDecl>(L)) {
12353 Pattern = cast<FieldDecl>(L);
12356 assert(Pattern && "We must have set the Pattern!");
12359 if (InstantiateInClassInitializer(Loc, Field, Pattern,
12360 getTemplateInstantiationArgs(Field))) {
12361 // Don't diagnose this again.
12362 Field->setInvalidDecl();
12363 return ExprError();
12365 return CXXDefaultInitExpr::Create(Context, Loc, Field);
12369 // If the brace-or-equal-initializer of a non-static data member
12370 // invokes a defaulted default constructor of its class or of an
12371 // enclosing class in a potentially evaluated subexpression, the
12372 // program is ill-formed.
12374 // This resolution is unworkable: the exception specification of the
12375 // default constructor can be needed in an unevaluated context, in
12376 // particular, in the operand of a noexcept-expression, and we can be
12377 // unable to compute an exception specification for an enclosed class.
12379 // Any attempt to resolve the exception specification of a defaulted default
12380 // constructor before the initializer is lexically complete will ultimately
12381 // come here at which point we can diagnose it.
12382 RecordDecl *OutermostClass = ParentRD->getOuterLexicalRecordContext();
12383 Diag(Loc, diag::err_in_class_initializer_not_yet_parsed)
12384 << OutermostClass << Field;
12385 Diag(Field->getLocEnd(), diag::note_in_class_initializer_not_yet_parsed);
12386 // Recover by marking the field invalid, unless we're in a SFINAE context.
12387 if (!isSFINAEContext())
12388 Field->setInvalidDecl();
12389 return ExprError();
12392 void Sema::FinalizeVarWithDestructor(VarDecl *VD, const RecordType *Record) {
12393 if (VD->isInvalidDecl()) return;
12395 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Record->getDecl());
12396 if (ClassDecl->isInvalidDecl()) return;
12397 if (ClassDecl->hasIrrelevantDestructor()) return;
12398 if (ClassDecl->isDependentContext()) return;
12400 CXXDestructorDecl *Destructor = LookupDestructor(ClassDecl);
12401 MarkFunctionReferenced(VD->getLocation(), Destructor);
12402 CheckDestructorAccess(VD->getLocation(), Destructor,
12403 PDiag(diag::err_access_dtor_var)
12404 << VD->getDeclName()
12406 DiagnoseUseOfDecl(Destructor, VD->getLocation());
12408 if (Destructor->isTrivial()) return;
12409 if (!VD->hasGlobalStorage()) return;
12411 // Emit warning for non-trivial dtor in global scope (a real global,
12412 // class-static, function-static).
12413 Diag(VD->getLocation(), diag::warn_exit_time_destructor);
12415 // TODO: this should be re-enabled for static locals by !CXAAtExit
12416 if (!VD->isStaticLocal())
12417 Diag(VD->getLocation(), diag::warn_global_destructor);
12420 /// \brief Given a constructor and the set of arguments provided for the
12421 /// constructor, convert the arguments and add any required default arguments
12422 /// to form a proper call to this constructor.
12424 /// \returns true if an error occurred, false otherwise.
12426 Sema::CompleteConstructorCall(CXXConstructorDecl *Constructor,
12427 MultiExprArg ArgsPtr,
12428 SourceLocation Loc,
12429 SmallVectorImpl<Expr*> &ConvertedArgs,
12430 bool AllowExplicit,
12431 bool IsListInitialization) {
12432 // FIXME: This duplicates a lot of code from Sema::ConvertArgumentsForCall.
12433 unsigned NumArgs = ArgsPtr.size();
12434 Expr **Args = ArgsPtr.data();
12436 const FunctionProtoType *Proto
12437 = Constructor->getType()->getAs<FunctionProtoType>();
12438 assert(Proto && "Constructor without a prototype?");
12439 unsigned NumParams = Proto->getNumParams();
12441 // If too few arguments are available, we'll fill in the rest with defaults.
12442 if (NumArgs < NumParams)
12443 ConvertedArgs.reserve(NumParams);
12445 ConvertedArgs.reserve(NumArgs);
12447 VariadicCallType CallType =
12448 Proto->isVariadic() ? VariadicConstructor : VariadicDoesNotApply;
12449 SmallVector<Expr *, 8> AllArgs;
12450 bool Invalid = GatherArgumentsForCall(Loc, Constructor,
12452 llvm::makeArrayRef(Args, NumArgs),
12454 CallType, AllowExplicit,
12455 IsListInitialization);
12456 ConvertedArgs.append(AllArgs.begin(), AllArgs.end());
12458 DiagnoseSentinelCalls(Constructor, Loc, AllArgs);
12460 CheckConstructorCall(Constructor,
12461 llvm::makeArrayRef(AllArgs.data(), AllArgs.size()),
12468 CheckOperatorNewDeleteDeclarationScope(Sema &SemaRef,
12469 const FunctionDecl *FnDecl) {
12470 const DeclContext *DC = FnDecl->getDeclContext()->getRedeclContext();
12471 if (isa<NamespaceDecl>(DC)) {
12472 return SemaRef.Diag(FnDecl->getLocation(),
12473 diag::err_operator_new_delete_declared_in_namespace)
12474 << FnDecl->getDeclName();
12477 if (isa<TranslationUnitDecl>(DC) &&
12478 FnDecl->getStorageClass() == SC_Static) {
12479 return SemaRef.Diag(FnDecl->getLocation(),
12480 diag::err_operator_new_delete_declared_static)
12481 << FnDecl->getDeclName();
12488 CheckOperatorNewDeleteTypes(Sema &SemaRef, const FunctionDecl *FnDecl,
12489 CanQualType ExpectedResultType,
12490 CanQualType ExpectedFirstParamType,
12491 unsigned DependentParamTypeDiag,
12492 unsigned InvalidParamTypeDiag) {
12493 QualType ResultType =
12494 FnDecl->getType()->getAs<FunctionType>()->getReturnType();
12496 // Check that the result type is not dependent.
12497 if (ResultType->isDependentType())
12498 return SemaRef.Diag(FnDecl->getLocation(),
12499 diag::err_operator_new_delete_dependent_result_type)
12500 << FnDecl->getDeclName() << ExpectedResultType;
12502 // Check that the result type is what we expect.
12503 if (SemaRef.Context.getCanonicalType(ResultType) != ExpectedResultType)
12504 return SemaRef.Diag(FnDecl->getLocation(),
12505 diag::err_operator_new_delete_invalid_result_type)
12506 << FnDecl->getDeclName() << ExpectedResultType;
12508 // A function template must have at least 2 parameters.
12509 if (FnDecl->getDescribedFunctionTemplate() && FnDecl->getNumParams() < 2)
12510 return SemaRef.Diag(FnDecl->getLocation(),
12511 diag::err_operator_new_delete_template_too_few_parameters)
12512 << FnDecl->getDeclName();
12514 // The function decl must have at least 1 parameter.
12515 if (FnDecl->getNumParams() == 0)
12516 return SemaRef.Diag(FnDecl->getLocation(),
12517 diag::err_operator_new_delete_too_few_parameters)
12518 << FnDecl->getDeclName();
12520 // Check the first parameter type is not dependent.
12521 QualType FirstParamType = FnDecl->getParamDecl(0)->getType();
12522 if (FirstParamType->isDependentType())
12523 return SemaRef.Diag(FnDecl->getLocation(), DependentParamTypeDiag)
12524 << FnDecl->getDeclName() << ExpectedFirstParamType;
12526 // Check that the first parameter type is what we expect.
12527 if (SemaRef.Context.getCanonicalType(FirstParamType).getUnqualifiedType() !=
12528 ExpectedFirstParamType)
12529 return SemaRef.Diag(FnDecl->getLocation(), InvalidParamTypeDiag)
12530 << FnDecl->getDeclName() << ExpectedFirstParamType;
12536 CheckOperatorNewDeclaration(Sema &SemaRef, const FunctionDecl *FnDecl) {
12537 // C++ [basic.stc.dynamic.allocation]p1:
12538 // A program is ill-formed if an allocation function is declared in a
12539 // namespace scope other than global scope or declared static in global
12541 if (CheckOperatorNewDeleteDeclarationScope(SemaRef, FnDecl))
12544 CanQualType SizeTy =
12545 SemaRef.Context.getCanonicalType(SemaRef.Context.getSizeType());
12547 // C++ [basic.stc.dynamic.allocation]p1:
12548 // The return type shall be void*. The first parameter shall have type
12550 if (CheckOperatorNewDeleteTypes(SemaRef, FnDecl, SemaRef.Context.VoidPtrTy,
12552 diag::err_operator_new_dependent_param_type,
12553 diag::err_operator_new_param_type))
12556 // C++ [basic.stc.dynamic.allocation]p1:
12557 // The first parameter shall not have an associated default argument.
12558 if (FnDecl->getParamDecl(0)->hasDefaultArg())
12559 return SemaRef.Diag(FnDecl->getLocation(),
12560 diag::err_operator_new_default_arg)
12561 << FnDecl->getDeclName() << FnDecl->getParamDecl(0)->getDefaultArgRange();
12567 CheckOperatorDeleteDeclaration(Sema &SemaRef, FunctionDecl *FnDecl) {
12568 // C++ [basic.stc.dynamic.deallocation]p1:
12569 // A program is ill-formed if deallocation functions are declared in a
12570 // namespace scope other than global scope or declared static in global
12572 if (CheckOperatorNewDeleteDeclarationScope(SemaRef, FnDecl))
12575 // C++ [basic.stc.dynamic.deallocation]p2:
12576 // Each deallocation function shall return void and its first parameter
12578 if (CheckOperatorNewDeleteTypes(SemaRef, FnDecl, SemaRef.Context.VoidTy,
12579 SemaRef.Context.VoidPtrTy,
12580 diag::err_operator_delete_dependent_param_type,
12581 diag::err_operator_delete_param_type))
12587 /// CheckOverloadedOperatorDeclaration - Check whether the declaration
12588 /// of this overloaded operator is well-formed. If so, returns false;
12589 /// otherwise, emits appropriate diagnostics and returns true.
12590 bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) {
12591 assert(FnDecl && FnDecl->isOverloadedOperator() &&
12592 "Expected an overloaded operator declaration");
12594 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator();
12596 // C++ [over.oper]p5:
12597 // The allocation and deallocation functions, operator new,
12598 // operator new[], operator delete and operator delete[], are
12599 // described completely in 3.7.3. The attributes and restrictions
12600 // found in the rest of this subclause do not apply to them unless
12601 // explicitly stated in 3.7.3.
12602 if (Op == OO_Delete || Op == OO_Array_Delete)
12603 return CheckOperatorDeleteDeclaration(*this, FnDecl);
12605 if (Op == OO_New || Op == OO_Array_New)
12606 return CheckOperatorNewDeclaration(*this, FnDecl);
12608 // C++ [over.oper]p6:
12609 // An operator function shall either be a non-static member
12610 // function or be a non-member function and have at least one
12611 // parameter whose type is a class, a reference to a class, an
12612 // enumeration, or a reference to an enumeration.
12613 if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl)) {
12614 if (MethodDecl->isStatic())
12615 return Diag(FnDecl->getLocation(),
12616 diag::err_operator_overload_static) << FnDecl->getDeclName();
12618 bool ClassOrEnumParam = false;
12619 for (auto Param : FnDecl->parameters()) {
12620 QualType ParamType = Param->getType().getNonReferenceType();
12621 if (ParamType->isDependentType() || ParamType->isRecordType() ||
12622 ParamType->isEnumeralType()) {
12623 ClassOrEnumParam = true;
12628 if (!ClassOrEnumParam)
12629 return Diag(FnDecl->getLocation(),
12630 diag::err_operator_overload_needs_class_or_enum)
12631 << FnDecl->getDeclName();
12634 // C++ [over.oper]p8:
12635 // An operator function cannot have default arguments (8.3.6),
12636 // except where explicitly stated below.
12638 // Only the function-call operator allows default arguments
12639 // (C++ [over.call]p1).
12640 if (Op != OO_Call) {
12641 for (auto Param : FnDecl->parameters()) {
12642 if (Param->hasDefaultArg())
12643 return Diag(Param->getLocation(),
12644 diag::err_operator_overload_default_arg)
12645 << FnDecl->getDeclName() << Param->getDefaultArgRange();
12649 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = {
12650 { false, false, false }
12651 #define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \
12652 , { Unary, Binary, MemberOnly }
12653 #include "clang/Basic/OperatorKinds.def"
12656 bool CanBeUnaryOperator = OperatorUses[Op][0];
12657 bool CanBeBinaryOperator = OperatorUses[Op][1];
12658 bool MustBeMemberOperator = OperatorUses[Op][2];
12660 // C++ [over.oper]p8:
12661 // [...] Operator functions cannot have more or fewer parameters
12662 // than the number required for the corresponding operator, as
12663 // described in the rest of this subclause.
12664 unsigned NumParams = FnDecl->getNumParams()
12665 + (isa<CXXMethodDecl>(FnDecl)? 1 : 0);
12666 if (Op != OO_Call &&
12667 ((NumParams == 1 && !CanBeUnaryOperator) ||
12668 (NumParams == 2 && !CanBeBinaryOperator) ||
12669 (NumParams < 1) || (NumParams > 2))) {
12670 // We have the wrong number of parameters.
12671 unsigned ErrorKind;
12672 if (CanBeUnaryOperator && CanBeBinaryOperator) {
12673 ErrorKind = 2; // 2 -> unary or binary.
12674 } else if (CanBeUnaryOperator) {
12675 ErrorKind = 0; // 0 -> unary
12677 assert(CanBeBinaryOperator &&
12678 "All non-call overloaded operators are unary or binary!");
12679 ErrorKind = 1; // 1 -> binary
12682 return Diag(FnDecl->getLocation(), diag::err_operator_overload_must_be)
12683 << FnDecl->getDeclName() << NumParams << ErrorKind;
12686 // Overloaded operators other than operator() cannot be variadic.
12687 if (Op != OO_Call &&
12688 FnDecl->getType()->getAs<FunctionProtoType>()->isVariadic()) {
12689 return Diag(FnDecl->getLocation(), diag::err_operator_overload_variadic)
12690 << FnDecl->getDeclName();
12693 // Some operators must be non-static member functions.
12694 if (MustBeMemberOperator && !isa<CXXMethodDecl>(FnDecl)) {
12695 return Diag(FnDecl->getLocation(),
12696 diag::err_operator_overload_must_be_member)
12697 << FnDecl->getDeclName();
12700 // C++ [over.inc]p1:
12701 // The user-defined function called operator++ implements the
12702 // prefix and postfix ++ operator. If this function is a member
12703 // function with no parameters, or a non-member function with one
12704 // parameter of class or enumeration type, it defines the prefix
12705 // increment operator ++ for objects of that type. If the function
12706 // is a member function with one parameter (which shall be of type
12707 // int) or a non-member function with two parameters (the second
12708 // of which shall be of type int), it defines the postfix
12709 // increment operator ++ for objects of that type.
12710 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) {
12711 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1);
12712 QualType ParamType = LastParam->getType();
12714 if (!ParamType->isSpecificBuiltinType(BuiltinType::Int) &&
12715 !ParamType->isDependentType())
12716 return Diag(LastParam->getLocation(),
12717 diag::err_operator_overload_post_incdec_must_be_int)
12718 << LastParam->getType() << (Op == OO_MinusMinus);
12725 checkLiteralOperatorTemplateParameterList(Sema &SemaRef,
12726 FunctionTemplateDecl *TpDecl) {
12727 TemplateParameterList *TemplateParams = TpDecl->getTemplateParameters();
12729 // Must have one or two template parameters.
12730 if (TemplateParams->size() == 1) {
12731 NonTypeTemplateParmDecl *PmDecl =
12732 dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(0));
12734 // The template parameter must be a char parameter pack.
12735 if (PmDecl && PmDecl->isTemplateParameterPack() &&
12736 SemaRef.Context.hasSameType(PmDecl->getType(), SemaRef.Context.CharTy))
12739 } else if (TemplateParams->size() == 2) {
12740 TemplateTypeParmDecl *PmType =
12741 dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(0));
12742 NonTypeTemplateParmDecl *PmArgs =
12743 dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(1));
12745 // The second template parameter must be a parameter pack with the
12746 // first template parameter as its type.
12747 if (PmType && PmArgs && !PmType->isTemplateParameterPack() &&
12748 PmArgs->isTemplateParameterPack()) {
12749 const TemplateTypeParmType *TArgs =
12750 PmArgs->getType()->getAs<TemplateTypeParmType>();
12751 if (TArgs && TArgs->getDepth() == PmType->getDepth() &&
12752 TArgs->getIndex() == PmType->getIndex()) {
12753 if (SemaRef.ActiveTemplateInstantiations.empty())
12754 SemaRef.Diag(TpDecl->getLocation(),
12755 diag::ext_string_literal_operator_template);
12761 SemaRef.Diag(TpDecl->getTemplateParameters()->getSourceRange().getBegin(),
12762 diag::err_literal_operator_template)
12763 << TpDecl->getTemplateParameters()->getSourceRange();
12767 /// CheckLiteralOperatorDeclaration - Check whether the declaration
12768 /// of this literal operator function is well-formed. If so, returns
12769 /// false; otherwise, emits appropriate diagnostics and returns true.
12770 bool Sema::CheckLiteralOperatorDeclaration(FunctionDecl *FnDecl) {
12771 if (isa<CXXMethodDecl>(FnDecl)) {
12772 Diag(FnDecl->getLocation(), diag::err_literal_operator_outside_namespace)
12773 << FnDecl->getDeclName();
12777 if (FnDecl->isExternC()) {
12778 Diag(FnDecl->getLocation(), diag::err_literal_operator_extern_c);
12779 if (const LinkageSpecDecl *LSD =
12780 FnDecl->getDeclContext()->getExternCContext())
12781 Diag(LSD->getExternLoc(), diag::note_extern_c_begins_here);
12785 // This might be the definition of a literal operator template.
12786 FunctionTemplateDecl *TpDecl = FnDecl->getDescribedFunctionTemplate();
12788 // This might be a specialization of a literal operator template.
12790 TpDecl = FnDecl->getPrimaryTemplate();
12792 // template <char...> type operator "" name() and
12793 // template <class T, T...> type operator "" name() are the only valid
12794 // template signatures, and the only valid signatures with no parameters.
12796 if (FnDecl->param_size() != 0) {
12797 Diag(FnDecl->getLocation(),
12798 diag::err_literal_operator_template_with_params);
12802 if (checkLiteralOperatorTemplateParameterList(*this, TpDecl))
12805 } else if (FnDecl->param_size() == 1) {
12806 const ParmVarDecl *Param = FnDecl->getParamDecl(0);
12808 QualType ParamType = Param->getType().getUnqualifiedType();
12810 // Only unsigned long long int, long double, any character type, and const
12811 // char * are allowed as the only parameters.
12812 if (ParamType->isSpecificBuiltinType(BuiltinType::ULongLong) ||
12813 ParamType->isSpecificBuiltinType(BuiltinType::LongDouble) ||
12814 Context.hasSameType(ParamType, Context.CharTy) ||
12815 Context.hasSameType(ParamType, Context.WideCharTy) ||
12816 Context.hasSameType(ParamType, Context.Char16Ty) ||
12817 Context.hasSameType(ParamType, Context.Char32Ty)) {
12818 } else if (const PointerType *Ptr = ParamType->getAs<PointerType>()) {
12819 QualType InnerType = Ptr->getPointeeType();
12821 // Pointer parameter must be a const char *.
12822 if (!(Context.hasSameType(InnerType.getUnqualifiedType(),
12824 InnerType.isConstQualified() && !InnerType.isVolatileQualified())) {
12825 Diag(Param->getSourceRange().getBegin(),
12826 diag::err_literal_operator_param)
12827 << ParamType << "'const char *'" << Param->getSourceRange();
12831 } else if (ParamType->isRealFloatingType()) {
12832 Diag(Param->getSourceRange().getBegin(), diag::err_literal_operator_param)
12833 << ParamType << Context.LongDoubleTy << Param->getSourceRange();
12836 } else if (ParamType->isIntegerType()) {
12837 Diag(Param->getSourceRange().getBegin(), diag::err_literal_operator_param)
12838 << ParamType << Context.UnsignedLongLongTy << Param->getSourceRange();
12842 Diag(Param->getSourceRange().getBegin(),
12843 diag::err_literal_operator_invalid_param)
12844 << ParamType << Param->getSourceRange();
12848 } else if (FnDecl->param_size() == 2) {
12849 FunctionDecl::param_iterator Param = FnDecl->param_begin();
12851 // First, verify that the first parameter is correct.
12853 QualType FirstParamType = (*Param)->getType().getUnqualifiedType();
12855 // Two parameter function must have a pointer to const as a
12856 // first parameter; let's strip those qualifiers.
12857 const PointerType *PT = FirstParamType->getAs<PointerType>();
12860 Diag((*Param)->getSourceRange().getBegin(),
12861 diag::err_literal_operator_param)
12862 << FirstParamType << "'const char *'" << (*Param)->getSourceRange();
12866 QualType PointeeType = PT->getPointeeType();
12867 // First parameter must be const
12868 if (!PointeeType.isConstQualified() || PointeeType.isVolatileQualified()) {
12869 Diag((*Param)->getSourceRange().getBegin(),
12870 diag::err_literal_operator_param)
12871 << FirstParamType << "'const char *'" << (*Param)->getSourceRange();
12875 QualType InnerType = PointeeType.getUnqualifiedType();
12876 // Only const char *, const wchar_t*, const char16_t*, and const char32_t*
12877 // are allowed as the first parameter to a two-parameter function
12878 if (!(Context.hasSameType(InnerType, Context.CharTy) ||
12879 Context.hasSameType(InnerType, Context.WideCharTy) ||
12880 Context.hasSameType(InnerType, Context.Char16Ty) ||
12881 Context.hasSameType(InnerType, Context.Char32Ty))) {
12882 Diag((*Param)->getSourceRange().getBegin(),
12883 diag::err_literal_operator_param)
12884 << FirstParamType << "'const char *'" << (*Param)->getSourceRange();
12888 // Move on to the second and final parameter.
12891 // The second parameter must be a std::size_t.
12892 QualType SecondParamType = (*Param)->getType().getUnqualifiedType();
12893 if (!Context.hasSameType(SecondParamType, Context.getSizeType())) {
12894 Diag((*Param)->getSourceRange().getBegin(),
12895 diag::err_literal_operator_param)
12896 << SecondParamType << Context.getSizeType()
12897 << (*Param)->getSourceRange();
12901 Diag(FnDecl->getLocation(), diag::err_literal_operator_bad_param_count);
12905 // Parameters are good.
12907 // A parameter-declaration-clause containing a default argument is not
12908 // equivalent to any of the permitted forms.
12909 for (auto Param : FnDecl->parameters()) {
12910 if (Param->hasDefaultArg()) {
12911 Diag(Param->getDefaultArgRange().getBegin(),
12912 diag::err_literal_operator_default_argument)
12913 << Param->getDefaultArgRange();
12918 StringRef LiteralName
12919 = FnDecl->getDeclName().getCXXLiteralIdentifier()->getName();
12920 if (LiteralName[0] != '_') {
12921 // C++11 [usrlit.suffix]p1:
12922 // Literal suffix identifiers that do not start with an underscore
12923 // are reserved for future standardization.
12924 Diag(FnDecl->getLocation(), diag::warn_user_literal_reserved)
12925 << StringLiteralParser::isValidUDSuffix(getLangOpts(), LiteralName);
12931 /// ActOnStartLinkageSpecification - Parsed the beginning of a C++
12932 /// linkage specification, including the language and (if present)
12933 /// the '{'. ExternLoc is the location of the 'extern', Lang is the
12934 /// language string literal. LBraceLoc, if valid, provides the location of
12935 /// the '{' brace. Otherwise, this linkage specification does not
12936 /// have any braces.
12937 Decl *Sema::ActOnStartLinkageSpecification(Scope *S, SourceLocation ExternLoc,
12939 SourceLocation LBraceLoc) {
12940 StringLiteral *Lit = cast<StringLiteral>(LangStr);
12941 if (!Lit->isAscii()) {
12942 Diag(LangStr->getExprLoc(), diag::err_language_linkage_spec_not_ascii)
12943 << LangStr->getSourceRange();
12947 StringRef Lang = Lit->getString();
12948 LinkageSpecDecl::LanguageIDs Language;
12950 Language = LinkageSpecDecl::lang_c;
12951 else if (Lang == "C++")
12952 Language = LinkageSpecDecl::lang_cxx;
12954 Diag(LangStr->getExprLoc(), diag::err_language_linkage_spec_unknown)
12955 << LangStr->getSourceRange();
12959 // FIXME: Add all the various semantics of linkage specifications
12961 LinkageSpecDecl *D = LinkageSpecDecl::Create(Context, CurContext, ExternLoc,
12962 LangStr->getExprLoc(), Language,
12963 LBraceLoc.isValid());
12964 CurContext->addDecl(D);
12965 PushDeclContext(S, D);
12969 /// ActOnFinishLinkageSpecification - Complete the definition of
12970 /// the C++ linkage specification LinkageSpec. If RBraceLoc is
12971 /// valid, it's the position of the closing '}' brace in a linkage
12972 /// specification that uses braces.
12973 Decl *Sema::ActOnFinishLinkageSpecification(Scope *S,
12975 SourceLocation RBraceLoc) {
12976 if (RBraceLoc.isValid()) {
12977 LinkageSpecDecl* LSDecl = cast<LinkageSpecDecl>(LinkageSpec);
12978 LSDecl->setRBraceLoc(RBraceLoc);
12981 return LinkageSpec;
12984 Decl *Sema::ActOnEmptyDeclaration(Scope *S,
12985 AttributeList *AttrList,
12986 SourceLocation SemiLoc) {
12987 Decl *ED = EmptyDecl::Create(Context, CurContext, SemiLoc);
12988 // Attribute declarations appertain to empty declaration so we handle
12991 ProcessDeclAttributeList(S, ED, AttrList);
12993 CurContext->addDecl(ED);
12997 /// \brief Perform semantic analysis for the variable declaration that
12998 /// occurs within a C++ catch clause, returning the newly-created
13000 VarDecl *Sema::BuildExceptionDeclaration(Scope *S,
13001 TypeSourceInfo *TInfo,
13002 SourceLocation StartLoc,
13003 SourceLocation Loc,
13004 IdentifierInfo *Name) {
13005 bool Invalid = false;
13006 QualType ExDeclType = TInfo->getType();
13008 // Arrays and functions decay.
13009 if (ExDeclType->isArrayType())
13010 ExDeclType = Context.getArrayDecayedType(ExDeclType);
13011 else if (ExDeclType->isFunctionType())
13012 ExDeclType = Context.getPointerType(ExDeclType);
13014 // C++ 15.3p1: The exception-declaration shall not denote an incomplete type.
13015 // The exception-declaration shall not denote a pointer or reference to an
13016 // incomplete type, other than [cv] void*.
13017 // N2844 forbids rvalue references.
13018 if (!ExDeclType->isDependentType() && ExDeclType->isRValueReferenceType()) {
13019 Diag(Loc, diag::err_catch_rvalue_ref);
13023 if (ExDeclType->isVariablyModifiedType()) {
13024 Diag(Loc, diag::err_catch_variably_modified) << ExDeclType;
13028 QualType BaseType = ExDeclType;
13029 int Mode = 0; // 0 for direct type, 1 for pointer, 2 for reference
13030 unsigned DK = diag::err_catch_incomplete;
13031 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) {
13032 BaseType = Ptr->getPointeeType();
13034 DK = diag::err_catch_incomplete_ptr;
13035 } else if (const ReferenceType *Ref = BaseType->getAs<ReferenceType>()) {
13036 // For the purpose of error recovery, we treat rvalue refs like lvalue refs.
13037 BaseType = Ref->getPointeeType();
13039 DK = diag::err_catch_incomplete_ref;
13041 if (!Invalid && (Mode == 0 || !BaseType->isVoidType()) &&
13042 !BaseType->isDependentType() && RequireCompleteType(Loc, BaseType, DK))
13045 if (!Invalid && !ExDeclType->isDependentType() &&
13046 RequireNonAbstractType(Loc, ExDeclType,
13047 diag::err_abstract_type_in_decl,
13048 AbstractVariableType))
13051 // Only the non-fragile NeXT runtime currently supports C++ catches
13052 // of ObjC types, and no runtime supports catching ObjC types by value.
13053 if (!Invalid && getLangOpts().ObjC1) {
13054 QualType T = ExDeclType;
13055 if (const ReferenceType *RT = T->getAs<ReferenceType>())
13056 T = RT->getPointeeType();
13058 if (T->isObjCObjectType()) {
13059 Diag(Loc, diag::err_objc_object_catch);
13061 } else if (T->isObjCObjectPointerType()) {
13062 // FIXME: should this be a test for macosx-fragile specifically?
13063 if (getLangOpts().ObjCRuntime.isFragile())
13064 Diag(Loc, diag::warn_objc_pointer_cxx_catch_fragile);
13068 VarDecl *ExDecl = VarDecl::Create(Context, CurContext, StartLoc, Loc, Name,
13069 ExDeclType, TInfo, SC_None);
13070 ExDecl->setExceptionVariable(true);
13072 // In ARC, infer 'retaining' for variables of retainable type.
13073 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(ExDecl))
13076 if (!Invalid && !ExDeclType->isDependentType()) {
13077 if (const RecordType *recordType = ExDeclType->getAs<RecordType>()) {
13078 // Insulate this from anything else we might currently be parsing.
13079 EnterExpressionEvaluationContext scope(*this, PotentiallyEvaluated);
13081 // C++ [except.handle]p16:
13082 // The object declared in an exception-declaration or, if the
13083 // exception-declaration does not specify a name, a temporary (12.2) is
13084 // copy-initialized (8.5) from the exception object. [...]
13085 // The object is destroyed when the handler exits, after the destruction
13086 // of any automatic objects initialized within the handler.
13088 // We just pretend to initialize the object with itself, then make sure
13089 // it can be destroyed later.
13090 QualType initType = Context.getExceptionObjectType(ExDeclType);
13092 InitializedEntity entity =
13093 InitializedEntity::InitializeVariable(ExDecl);
13094 InitializationKind initKind =
13095 InitializationKind::CreateCopy(Loc, SourceLocation());
13097 Expr *opaqueValue =
13098 new (Context) OpaqueValueExpr(Loc, initType, VK_LValue, OK_Ordinary);
13099 InitializationSequence sequence(*this, entity, initKind, opaqueValue);
13100 ExprResult result = sequence.Perform(*this, entity, initKind, opaqueValue);
13101 if (result.isInvalid())
13104 // If the constructor used was non-trivial, set this as the
13106 CXXConstructExpr *construct = result.getAs<CXXConstructExpr>();
13107 if (!construct->getConstructor()->isTrivial()) {
13108 Expr *init = MaybeCreateExprWithCleanups(construct);
13109 ExDecl->setInit(init);
13112 // And make sure it's destructable.
13113 FinalizeVarWithDestructor(ExDecl, recordType);
13119 ExDecl->setInvalidDecl();
13124 /// ActOnExceptionDeclarator - Parsed the exception-declarator in a C++ catch
13126 Decl *Sema::ActOnExceptionDeclarator(Scope *S, Declarator &D) {
13127 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
13128 bool Invalid = D.isInvalidType();
13130 // Check for unexpanded parameter packs.
13131 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
13132 UPPC_ExceptionType)) {
13133 TInfo = Context.getTrivialTypeSourceInfo(Context.IntTy,
13134 D.getIdentifierLoc());
13138 IdentifierInfo *II = D.getIdentifier();
13139 if (NamedDecl *PrevDecl = LookupSingleName(S, II, D.getIdentifierLoc(),
13140 LookupOrdinaryName,
13141 ForRedeclaration)) {
13142 // The scope should be freshly made just for us. There is just no way
13143 // it contains any previous declaration, except for function parameters in
13144 // a function-try-block's catch statement.
13145 assert(!S->isDeclScope(PrevDecl));
13146 if (isDeclInScope(PrevDecl, CurContext, S)) {
13147 Diag(D.getIdentifierLoc(), diag::err_redefinition)
13148 << D.getIdentifier();
13149 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
13151 } else if (PrevDecl->isTemplateParameter())
13152 // Maybe we will complain about the shadowed template parameter.
13153 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
13156 if (D.getCXXScopeSpec().isSet() && !Invalid) {
13157 Diag(D.getIdentifierLoc(), diag::err_qualified_catch_declarator)
13158 << D.getCXXScopeSpec().getRange();
13162 VarDecl *ExDecl = BuildExceptionDeclaration(S, TInfo,
13164 D.getIdentifierLoc(),
13165 D.getIdentifier());
13167 ExDecl->setInvalidDecl();
13169 // Add the exception declaration into this scope.
13171 PushOnScopeChains(ExDecl, S);
13173 CurContext->addDecl(ExDecl);
13175 ProcessDeclAttributes(S, ExDecl, D);
13179 Decl *Sema::ActOnStaticAssertDeclaration(SourceLocation StaticAssertLoc,
13181 Expr *AssertMessageExpr,
13182 SourceLocation RParenLoc) {
13183 StringLiteral *AssertMessage =
13184 AssertMessageExpr ? cast<StringLiteral>(AssertMessageExpr) : nullptr;
13186 if (DiagnoseUnexpandedParameterPack(AssertExpr, UPPC_StaticAssertExpression))
13189 return BuildStaticAssertDeclaration(StaticAssertLoc, AssertExpr,
13190 AssertMessage, RParenLoc, false);
13193 Decl *Sema::BuildStaticAssertDeclaration(SourceLocation StaticAssertLoc,
13195 StringLiteral *AssertMessage,
13196 SourceLocation RParenLoc,
13198 assert(AssertExpr != nullptr && "Expected non-null condition");
13199 if (!AssertExpr->isTypeDependent() && !AssertExpr->isValueDependent() &&
13201 // In a static_assert-declaration, the constant-expression shall be a
13202 // constant expression that can be contextually converted to bool.
13203 ExprResult Converted = PerformContextuallyConvertToBool(AssertExpr);
13204 if (Converted.isInvalid())
13208 if (!Failed && VerifyIntegerConstantExpression(Converted.get(), &Cond,
13209 diag::err_static_assert_expression_is_not_constant,
13210 /*AllowFold=*/false).isInvalid())
13213 if (!Failed && !Cond) {
13214 SmallString<256> MsgBuffer;
13215 llvm::raw_svector_ostream Msg(MsgBuffer);
13217 AssertMessage->printPretty(Msg, nullptr, getPrintingPolicy());
13218 Diag(StaticAssertLoc, diag::err_static_assert_failed)
13219 << !AssertMessage << Msg.str() << AssertExpr->getSourceRange();
13224 Decl *Decl = StaticAssertDecl::Create(Context, CurContext, StaticAssertLoc,
13225 AssertExpr, AssertMessage, RParenLoc,
13228 CurContext->addDecl(Decl);
13232 /// \brief Perform semantic analysis of the given friend type declaration.
13234 /// \returns A friend declaration that.
13235 FriendDecl *Sema::CheckFriendTypeDecl(SourceLocation LocStart,
13236 SourceLocation FriendLoc,
13237 TypeSourceInfo *TSInfo) {
13238 assert(TSInfo && "NULL TypeSourceInfo for friend type declaration");
13240 QualType T = TSInfo->getType();
13241 SourceRange TypeRange = TSInfo->getTypeLoc().getLocalSourceRange();
13243 // C++03 [class.friend]p2:
13244 // An elaborated-type-specifier shall be used in a friend declaration
13247 // * The class-key of the elaborated-type-specifier is required.
13248 if (!ActiveTemplateInstantiations.empty()) {
13249 // Do not complain about the form of friend template types during
13250 // template instantiation; we will already have complained when the
13251 // template was declared.
13253 if (!T->isElaboratedTypeSpecifier()) {
13254 // If we evaluated the type to a record type, suggest putting
13256 if (const RecordType *RT = T->getAs<RecordType>()) {
13257 RecordDecl *RD = RT->getDecl();
13259 SmallString<16> InsertionText(" ");
13260 InsertionText += RD->getKindName();
13262 Diag(TypeRange.getBegin(),
13263 getLangOpts().CPlusPlus11 ?
13264 diag::warn_cxx98_compat_unelaborated_friend_type :
13265 diag::ext_unelaborated_friend_type)
13266 << (unsigned) RD->getTagKind()
13268 << FixItHint::CreateInsertion(getLocForEndOfToken(FriendLoc),
13272 getLangOpts().CPlusPlus11 ?
13273 diag::warn_cxx98_compat_nonclass_type_friend :
13274 diag::ext_nonclass_type_friend)
13278 } else if (T->getAs<EnumType>()) {
13280 getLangOpts().CPlusPlus11 ?
13281 diag::warn_cxx98_compat_enum_friend :
13282 diag::ext_enum_friend)
13287 // C++11 [class.friend]p3:
13288 // A friend declaration that does not declare a function shall have one
13289 // of the following forms:
13290 // friend elaborated-type-specifier ;
13291 // friend simple-type-specifier ;
13292 // friend typename-specifier ;
13293 if (getLangOpts().CPlusPlus11 && LocStart != FriendLoc)
13294 Diag(FriendLoc, diag::err_friend_not_first_in_declaration) << T;
13297 // If the type specifier in a friend declaration designates a (possibly
13298 // cv-qualified) class type, that class is declared as a friend; otherwise,
13299 // the friend declaration is ignored.
13300 return FriendDecl::Create(Context, CurContext,
13301 TSInfo->getTypeLoc().getLocStart(), TSInfo,
13305 /// Handle a friend tag declaration where the scope specifier was
13307 Decl *Sema::ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
13308 unsigned TagSpec, SourceLocation TagLoc,
13310 IdentifierInfo *Name,
13311 SourceLocation NameLoc,
13312 AttributeList *Attr,
13313 MultiTemplateParamsArg TempParamLists) {
13314 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
13316 bool isExplicitSpecialization = false;
13317 bool Invalid = false;
13319 if (TemplateParameterList *TemplateParams =
13320 MatchTemplateParametersToScopeSpecifier(
13321 TagLoc, NameLoc, SS, nullptr, TempParamLists, /*friend*/ true,
13322 isExplicitSpecialization, Invalid)) {
13323 if (TemplateParams->size() > 0) {
13324 // This is a declaration of a class template.
13328 return CheckClassTemplate(S, TagSpec, TUK_Friend, TagLoc, SS, Name,
13329 NameLoc, Attr, TemplateParams, AS_public,
13330 /*ModulePrivateLoc=*/SourceLocation(),
13331 FriendLoc, TempParamLists.size() - 1,
13332 TempParamLists.data()).get();
13334 // The "template<>" header is extraneous.
13335 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
13336 << TypeWithKeyword::getTagTypeKindName(Kind) << Name;
13337 isExplicitSpecialization = true;
13341 if (Invalid) return nullptr;
13343 bool isAllExplicitSpecializations = true;
13344 for (unsigned I = TempParamLists.size(); I-- > 0; ) {
13345 if (TempParamLists[I]->size()) {
13346 isAllExplicitSpecializations = false;
13351 // FIXME: don't ignore attributes.
13353 // If it's explicit specializations all the way down, just forget
13354 // about the template header and build an appropriate non-templated
13355 // friend. TODO: for source fidelity, remember the headers.
13356 if (isAllExplicitSpecializations) {
13357 if (SS.isEmpty()) {
13358 bool Owned = false;
13359 bool IsDependent = false;
13360 return ActOnTag(S, TagSpec, TUK_Friend, TagLoc, SS, Name, NameLoc,
13362 /*ModulePrivateLoc=*/SourceLocation(),
13363 MultiTemplateParamsArg(), Owned, IsDependent,
13364 /*ScopedEnumKWLoc=*/SourceLocation(),
13365 /*ScopedEnumUsesClassTag=*/false,
13366 /*UnderlyingType=*/TypeResult(),
13367 /*IsTypeSpecifier=*/false);
13370 NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
13371 ElaboratedTypeKeyword Keyword
13372 = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
13373 QualType T = CheckTypenameType(Keyword, TagLoc, QualifierLoc,
13378 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
13379 if (isa<DependentNameType>(T)) {
13380 DependentNameTypeLoc TL =
13381 TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
13382 TL.setElaboratedKeywordLoc(TagLoc);
13383 TL.setQualifierLoc(QualifierLoc);
13384 TL.setNameLoc(NameLoc);
13386 ElaboratedTypeLoc TL = TSI->getTypeLoc().castAs<ElaboratedTypeLoc>();
13387 TL.setElaboratedKeywordLoc(TagLoc);
13388 TL.setQualifierLoc(QualifierLoc);
13389 TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(NameLoc);
13392 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, NameLoc,
13393 TSI, FriendLoc, TempParamLists);
13394 Friend->setAccess(AS_public);
13395 CurContext->addDecl(Friend);
13399 assert(SS.isNotEmpty() && "valid templated tag with no SS and no direct?");
13403 // Handle the case of a templated-scope friend class. e.g.
13404 // template <class T> class A<T>::B;
13405 // FIXME: we don't support these right now.
13406 Diag(NameLoc, diag::warn_template_qualified_friend_unsupported)
13407 << SS.getScopeRep() << SS.getRange() << cast<CXXRecordDecl>(CurContext);
13408 ElaboratedTypeKeyword ETK = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
13409 QualType T = Context.getDependentNameType(ETK, SS.getScopeRep(), Name);
13410 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
13411 DependentNameTypeLoc TL = TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
13412 TL.setElaboratedKeywordLoc(TagLoc);
13413 TL.setQualifierLoc(SS.getWithLocInContext(Context));
13414 TL.setNameLoc(NameLoc);
13416 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, NameLoc,
13417 TSI, FriendLoc, TempParamLists);
13418 Friend->setAccess(AS_public);
13419 Friend->setUnsupportedFriend(true);
13420 CurContext->addDecl(Friend);
13425 /// Handle a friend type declaration. This works in tandem with
13428 /// Notes on friend class templates:
13430 /// We generally treat friend class declarations as if they were
13431 /// declaring a class. So, for example, the elaborated type specifier
13432 /// in a friend declaration is required to obey the restrictions of a
13433 /// class-head (i.e. no typedefs in the scope chain), template
13434 /// parameters are required to match up with simple template-ids, &c.
13435 /// However, unlike when declaring a template specialization, it's
13436 /// okay to refer to a template specialization without an empty
13437 /// template parameter declaration, e.g.
13438 /// friend class A<T>::B<unsigned>;
13439 /// We permit this as a special case; if there are any template
13440 /// parameters present at all, require proper matching, i.e.
13441 /// template <> template \<class T> friend class A<int>::B;
13442 Decl *Sema::ActOnFriendTypeDecl(Scope *S, const DeclSpec &DS,
13443 MultiTemplateParamsArg TempParams) {
13444 SourceLocation Loc = DS.getLocStart();
13446 assert(DS.isFriendSpecified());
13447 assert(DS.getStorageClassSpec() == DeclSpec::SCS_unspecified);
13449 // Try to convert the decl specifier to a type. This works for
13450 // friend templates because ActOnTag never produces a ClassTemplateDecl
13451 // for a TUK_Friend.
13452 Declarator TheDeclarator(DS, Declarator::MemberContext);
13453 TypeSourceInfo *TSI = GetTypeForDeclarator(TheDeclarator, S);
13454 QualType T = TSI->getType();
13455 if (TheDeclarator.isInvalidType())
13458 if (DiagnoseUnexpandedParameterPack(Loc, TSI, UPPC_FriendDeclaration))
13461 // This is definitely an error in C++98. It's probably meant to
13462 // be forbidden in C++0x, too, but the specification is just
13465 // The problem is with declarations like the following:
13466 // template <T> friend A<T>::foo;
13467 // where deciding whether a class C is a friend or not now hinges
13468 // on whether there exists an instantiation of A that causes
13469 // 'foo' to equal C. There are restrictions on class-heads
13470 // (which we declare (by fiat) elaborated friend declarations to
13471 // be) that makes this tractable.
13473 // FIXME: handle "template <> friend class A<T>;", which
13474 // is possibly well-formed? Who even knows?
13475 if (TempParams.size() && !T->isElaboratedTypeSpecifier()) {
13476 Diag(Loc, diag::err_tagless_friend_type_template)
13477 << DS.getSourceRange();
13481 // C++98 [class.friend]p1: A friend of a class is a function
13482 // or class that is not a member of the class . . .
13483 // This is fixed in DR77, which just barely didn't make the C++03
13484 // deadline. It's also a very silly restriction that seriously
13485 // affects inner classes and which nobody else seems to implement;
13486 // thus we never diagnose it, not even in -pedantic.
13488 // But note that we could warn about it: it's always useless to
13489 // friend one of your own members (it's not, however, worthless to
13490 // friend a member of an arbitrary specialization of your template).
13493 if (!TempParams.empty())
13494 D = FriendTemplateDecl::Create(Context, CurContext, Loc,
13497 DS.getFriendSpecLoc());
13499 D = CheckFriendTypeDecl(Loc, DS.getFriendSpecLoc(), TSI);
13504 D->setAccess(AS_public);
13505 CurContext->addDecl(D);
13510 NamedDecl *Sema::ActOnFriendFunctionDecl(Scope *S, Declarator &D,
13511 MultiTemplateParamsArg TemplateParams) {
13512 const DeclSpec &DS = D.getDeclSpec();
13514 assert(DS.isFriendSpecified());
13515 assert(DS.getStorageClassSpec() == DeclSpec::SCS_unspecified);
13517 SourceLocation Loc = D.getIdentifierLoc();
13518 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
13520 // C++ [class.friend]p1
13521 // A friend of a class is a function or class....
13522 // Note that this sees through typedefs, which is intended.
13523 // It *doesn't* see through dependent types, which is correct
13524 // according to [temp.arg.type]p3:
13525 // If a declaration acquires a function type through a
13526 // type dependent on a template-parameter and this causes
13527 // a declaration that does not use the syntactic form of a
13528 // function declarator to have a function type, the program
13530 if (!TInfo->getType()->isFunctionType()) {
13531 Diag(Loc, diag::err_unexpected_friend);
13533 // It might be worthwhile to try to recover by creating an
13534 // appropriate declaration.
13538 // C++ [namespace.memdef]p3
13539 // - If a friend declaration in a non-local class first declares a
13540 // class or function, the friend class or function is a member
13541 // of the innermost enclosing namespace.
13542 // - The name of the friend is not found by simple name lookup
13543 // until a matching declaration is provided in that namespace
13544 // scope (either before or after the class declaration granting
13546 // - If a friend function is called, its name may be found by the
13547 // name lookup that considers functions from namespaces and
13548 // classes associated with the types of the function arguments.
13549 // - When looking for a prior declaration of a class or a function
13550 // declared as a friend, scopes outside the innermost enclosing
13551 // namespace scope are not considered.
13553 CXXScopeSpec &SS = D.getCXXScopeSpec();
13554 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
13555 DeclarationName Name = NameInfo.getName();
13558 // Check for unexpanded parameter packs.
13559 if (DiagnoseUnexpandedParameterPack(Loc, TInfo, UPPC_FriendDeclaration) ||
13560 DiagnoseUnexpandedParameterPack(NameInfo, UPPC_FriendDeclaration) ||
13561 DiagnoseUnexpandedParameterPack(SS, UPPC_FriendDeclaration))
13564 // The context we found the declaration in, or in which we should
13565 // create the declaration.
13567 Scope *DCScope = S;
13568 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
13571 // There are five cases here.
13572 // - There's no scope specifier and we're in a local class. Only look
13573 // for functions declared in the immediately-enclosing block scope.
13574 // We recover from invalid scope qualifiers as if they just weren't there.
13575 FunctionDecl *FunctionContainingLocalClass = nullptr;
13576 if ((SS.isInvalid() || !SS.isSet()) &&
13577 (FunctionContainingLocalClass =
13578 cast<CXXRecordDecl>(CurContext)->isLocalClass())) {
13579 // C++11 [class.friend]p11:
13580 // If a friend declaration appears in a local class and the name
13581 // specified is an unqualified name, a prior declaration is
13582 // looked up without considering scopes that are outside the
13583 // innermost enclosing non-class scope. For a friend function
13584 // declaration, if there is no prior declaration, the program is
13587 // Find the innermost enclosing non-class scope. This is the block
13588 // scope containing the local class definition (or for a nested class,
13589 // the outer local class).
13590 DCScope = S->getFnParent();
13592 // Look up the function name in the scope.
13593 Previous.clear(LookupLocalFriendName);
13594 LookupName(Previous, S, /*AllowBuiltinCreation*/false);
13596 if (!Previous.empty()) {
13597 // All possible previous declarations must have the same context:
13598 // either they were declared at block scope or they are members of
13599 // one of the enclosing local classes.
13600 DC = Previous.getRepresentativeDecl()->getDeclContext();
13602 // This is ill-formed, but provide the context that we would have
13603 // declared the function in, if we were permitted to, for error recovery.
13604 DC = FunctionContainingLocalClass;
13606 adjustContextForLocalExternDecl(DC);
13608 // C++ [class.friend]p6:
13609 // A function can be defined in a friend declaration of a class if and
13610 // only if the class is a non-local class (9.8), the function name is
13611 // unqualified, and the function has namespace scope.
13612 if (D.isFunctionDefinition()) {
13613 Diag(NameInfo.getBeginLoc(), diag::err_friend_def_in_local_class);
13616 // - There's no scope specifier, in which case we just go to the
13617 // appropriate scope and look for a function or function template
13618 // there as appropriate.
13619 } else if (SS.isInvalid() || !SS.isSet()) {
13620 // C++11 [namespace.memdef]p3:
13621 // If the name in a friend declaration is neither qualified nor
13622 // a template-id and the declaration is a function or an
13623 // elaborated-type-specifier, the lookup to determine whether
13624 // the entity has been previously declared shall not consider
13625 // any scopes outside the innermost enclosing namespace.
13626 bool isTemplateId = D.getName().getKind() == UnqualifiedId::IK_TemplateId;
13628 // Find the appropriate context according to the above.
13631 // Skip class contexts. If someone can cite chapter and verse
13632 // for this behavior, that would be nice --- it's what GCC and
13633 // EDG do, and it seems like a reasonable intent, but the spec
13634 // really only says that checks for unqualified existing
13635 // declarations should stop at the nearest enclosing namespace,
13636 // not that they should only consider the nearest enclosing
13638 while (DC->isRecord())
13639 DC = DC->getParent();
13641 DeclContext *LookupDC = DC;
13642 while (LookupDC->isTransparentContext())
13643 LookupDC = LookupDC->getParent();
13646 LookupQualifiedName(Previous, LookupDC);
13648 if (!Previous.empty()) {
13653 if (isTemplateId) {
13654 if (isa<TranslationUnitDecl>(LookupDC)) break;
13656 if (LookupDC->isFileContext()) break;
13658 LookupDC = LookupDC->getParent();
13661 DCScope = getScopeForDeclContext(S, DC);
13663 // - There's a non-dependent scope specifier, in which case we
13664 // compute it and do a previous lookup there for a function
13665 // or function template.
13666 } else if (!SS.getScopeRep()->isDependent()) {
13667 DC = computeDeclContext(SS);
13668 if (!DC) return nullptr;
13670 if (RequireCompleteDeclContext(SS, DC)) return nullptr;
13672 LookupQualifiedName(Previous, DC);
13674 // Ignore things found implicitly in the wrong scope.
13675 // TODO: better diagnostics for this case. Suggesting the right
13676 // qualified scope would be nice...
13677 LookupResult::Filter F = Previous.makeFilter();
13678 while (F.hasNext()) {
13679 NamedDecl *D = F.next();
13680 if (!DC->InEnclosingNamespaceSetOf(
13681 D->getDeclContext()->getRedeclContext()))
13686 if (Previous.empty()) {
13687 D.setInvalidType();
13688 Diag(Loc, diag::err_qualified_friend_not_found)
13689 << Name << TInfo->getType();
13693 // C++ [class.friend]p1: A friend of a class is a function or
13694 // class that is not a member of the class . . .
13695 if (DC->Equals(CurContext))
13696 Diag(DS.getFriendSpecLoc(),
13697 getLangOpts().CPlusPlus11 ?
13698 diag::warn_cxx98_compat_friend_is_member :
13699 diag::err_friend_is_member);
13701 if (D.isFunctionDefinition()) {
13702 // C++ [class.friend]p6:
13703 // A function can be defined in a friend declaration of a class if and
13704 // only if the class is a non-local class (9.8), the function name is
13705 // unqualified, and the function has namespace scope.
13706 SemaDiagnosticBuilder DB
13707 = Diag(SS.getRange().getBegin(), diag::err_qualified_friend_def);
13709 DB << SS.getScopeRep();
13710 if (DC->isFileContext())
13711 DB << FixItHint::CreateRemoval(SS.getRange());
13715 // - There's a scope specifier that does not match any template
13716 // parameter lists, in which case we use some arbitrary context,
13717 // create a method or method template, and wait for instantiation.
13718 // - There's a scope specifier that does match some template
13719 // parameter lists, which we don't handle right now.
13721 if (D.isFunctionDefinition()) {
13722 // C++ [class.friend]p6:
13723 // A function can be defined in a friend declaration of a class if and
13724 // only if the class is a non-local class (9.8), the function name is
13725 // unqualified, and the function has namespace scope.
13726 Diag(SS.getRange().getBegin(), diag::err_qualified_friend_def)
13727 << SS.getScopeRep();
13731 assert(isa<CXXRecordDecl>(DC) && "friend declaration not in class?");
13734 if (!DC->isRecord()) {
13736 switch (D.getName().getKind()) {
13737 case UnqualifiedId::IK_ConstructorTemplateId:
13738 case UnqualifiedId::IK_ConstructorName:
13741 case UnqualifiedId::IK_DestructorName:
13744 case UnqualifiedId::IK_ConversionFunctionId:
13747 case UnqualifiedId::IK_Identifier:
13748 case UnqualifiedId::IK_ImplicitSelfParam:
13749 case UnqualifiedId::IK_LiteralOperatorId:
13750 case UnqualifiedId::IK_OperatorFunctionId:
13751 case UnqualifiedId::IK_TemplateId:
13754 // This implies that it has to be an operator or function.
13755 if (DiagArg >= 0) {
13756 Diag(Loc, diag::err_introducing_special_friend) << DiagArg;
13761 // FIXME: This is an egregious hack to cope with cases where the scope stack
13762 // does not contain the declaration context, i.e., in an out-of-line
13763 // definition of a class.
13764 Scope FakeDCScope(S, Scope::DeclScope, Diags);
13766 FakeDCScope.setEntity(DC);
13767 DCScope = &FakeDCScope;
13770 bool AddToScope = true;
13771 NamedDecl *ND = ActOnFunctionDeclarator(DCScope, D, DC, TInfo, Previous,
13772 TemplateParams, AddToScope);
13773 if (!ND) return nullptr;
13775 assert(ND->getLexicalDeclContext() == CurContext);
13777 // If we performed typo correction, we might have added a scope specifier
13778 // and changed the decl context.
13779 DC = ND->getDeclContext();
13781 // Add the function declaration to the appropriate lookup tables,
13782 // adjusting the redeclarations list as necessary. We don't
13783 // want to do this yet if the friending class is dependent.
13785 // Also update the scope-based lookup if the target context's
13786 // lookup context is in lexical scope.
13787 if (!CurContext->isDependentContext()) {
13788 DC = DC->getRedeclContext();
13789 DC->makeDeclVisibleInContext(ND);
13790 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
13791 PushOnScopeChains(ND, EnclosingScope, /*AddToContext=*/ false);
13794 FriendDecl *FrD = FriendDecl::Create(Context, CurContext,
13795 D.getIdentifierLoc(), ND,
13796 DS.getFriendSpecLoc());
13797 FrD->setAccess(AS_public);
13798 CurContext->addDecl(FrD);
13800 if (ND->isInvalidDecl()) {
13801 FrD->setInvalidDecl();
13803 if (DC->isRecord()) CheckFriendAccess(ND);
13806 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
13807 FD = FTD->getTemplatedDecl();
13809 FD = cast<FunctionDecl>(ND);
13811 // C++11 [dcl.fct.default]p4: If a friend declaration specifies a
13812 // default argument expression, that declaration shall be a definition
13813 // and shall be the only declaration of the function or function
13814 // template in the translation unit.
13815 if (functionDeclHasDefaultArgument(FD)) {
13816 // We can't look at FD->getPreviousDecl() because it may not have been set
13817 // if we're in a dependent context. If the function is known to be a
13818 // redeclaration, we will have narrowed Previous down to the right decl.
13819 if (D.isRedeclaration()) {
13820 Diag(FD->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
13821 Diag(Previous.getRepresentativeDecl()->getLocation(),
13822 diag::note_previous_declaration);
13823 } else if (!D.isFunctionDefinition())
13824 Diag(FD->getLocation(), diag::err_friend_decl_with_def_arg_must_be_def);
13827 // Mark templated-scope function declarations as unsupported.
13828 if (FD->getNumTemplateParameterLists() && SS.isValid()) {
13829 Diag(FD->getLocation(), diag::warn_template_qualified_friend_unsupported)
13830 << SS.getScopeRep() << SS.getRange()
13831 << cast<CXXRecordDecl>(CurContext);
13832 FrD->setUnsupportedFriend(true);
13839 void Sema::SetDeclDeleted(Decl *Dcl, SourceLocation DelLoc) {
13840 AdjustDeclIfTemplate(Dcl);
13842 FunctionDecl *Fn = dyn_cast_or_null<FunctionDecl>(Dcl);
13844 Diag(DelLoc, diag::err_deleted_non_function);
13848 if (const FunctionDecl *Prev = Fn->getPreviousDecl()) {
13849 // Don't consider the implicit declaration we generate for explicit
13850 // specializations. FIXME: Do not generate these implicit declarations.
13851 if ((Prev->getTemplateSpecializationKind() != TSK_ExplicitSpecialization ||
13852 Prev->getPreviousDecl()) &&
13853 !Prev->isDefined()) {
13854 Diag(DelLoc, diag::err_deleted_decl_not_first);
13855 Diag(Prev->getLocation().isInvalid() ? DelLoc : Prev->getLocation(),
13856 Prev->isImplicit() ? diag::note_previous_implicit_declaration
13857 : diag::note_previous_declaration);
13859 // If the declaration wasn't the first, we delete the function anyway for
13861 Fn = Fn->getCanonicalDecl();
13864 // dllimport/dllexport cannot be deleted.
13865 if (const InheritableAttr *DLLAttr = getDLLAttr(Fn)) {
13866 Diag(Fn->getLocation(), diag::err_attribute_dll_deleted) << DLLAttr;
13867 Fn->setInvalidDecl();
13870 if (Fn->isDeleted())
13873 // See if we're deleting a function which is already known to override a
13874 // non-deleted virtual function.
13875 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Fn)) {
13876 bool IssuedDiagnostic = false;
13877 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
13878 E = MD->end_overridden_methods();
13880 if (!(*MD->begin_overridden_methods())->isDeleted()) {
13881 if (!IssuedDiagnostic) {
13882 Diag(DelLoc, diag::err_deleted_override) << MD->getDeclName();
13883 IssuedDiagnostic = true;
13885 Diag((*I)->getLocation(), diag::note_overridden_virtual_function);
13888 // If this function was implicitly deleted because it was defaulted,
13889 // explain why it was deleted.
13890 if (IssuedDiagnostic && MD->isDefaulted())
13891 ShouldDeleteSpecialMember(MD, getSpecialMember(MD), nullptr,
13895 // C++11 [basic.start.main]p3:
13896 // A program that defines main as deleted [...] is ill-formed.
13898 Diag(DelLoc, diag::err_deleted_main);
13900 // C++11 [dcl.fct.def.delete]p4:
13901 // A deleted function is implicitly inline.
13902 Fn->setImplicitlyInline();
13903 Fn->setDeletedAsWritten();
13906 void Sema::SetDeclDefaulted(Decl *Dcl, SourceLocation DefaultLoc) {
13907 CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Dcl);
13910 if (MD->getParent()->isDependentType()) {
13911 MD->setDefaulted();
13912 MD->setExplicitlyDefaulted();
13916 CXXSpecialMember Member = getSpecialMember(MD);
13917 if (Member == CXXInvalid) {
13918 if (!MD->isInvalidDecl())
13919 Diag(DefaultLoc, diag::err_default_special_members);
13923 MD->setDefaulted();
13924 MD->setExplicitlyDefaulted();
13926 // If this definition appears within the record, do the checking when
13927 // the record is complete.
13928 const FunctionDecl *Primary = MD;
13929 if (const FunctionDecl *Pattern = MD->getTemplateInstantiationPattern())
13930 // Ask the template instantiation pattern that actually had the
13931 // '= default' on it.
13934 // If the method was defaulted on its first declaration, we will have
13935 // already performed the checking in CheckCompletedCXXClass. Such a
13936 // declaration doesn't trigger an implicit definition.
13937 if (Primary->getCanonicalDecl()->isDefaulted())
13940 CheckExplicitlyDefaultedSpecialMember(MD);
13942 if (!MD->isInvalidDecl())
13943 DefineImplicitSpecialMember(*this, MD, DefaultLoc);
13945 Diag(DefaultLoc, diag::err_default_special_members);
13949 static void SearchForReturnInStmt(Sema &Self, Stmt *S) {
13950 for (Stmt *SubStmt : S->children()) {
13953 if (isa<ReturnStmt>(SubStmt))
13954 Self.Diag(SubStmt->getLocStart(),
13955 diag::err_return_in_constructor_handler);
13956 if (!isa<Expr>(SubStmt))
13957 SearchForReturnInStmt(Self, SubStmt);
13961 void Sema::DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock) {
13962 for (unsigned I = 0, E = TryBlock->getNumHandlers(); I != E; ++I) {
13963 CXXCatchStmt *Handler = TryBlock->getHandler(I);
13964 SearchForReturnInStmt(*this, Handler);
13968 bool Sema::CheckOverridingFunctionAttributes(const CXXMethodDecl *New,
13969 const CXXMethodDecl *Old) {
13970 const FunctionType *NewFT = New->getType()->getAs<FunctionType>();
13971 const FunctionType *OldFT = Old->getType()->getAs<FunctionType>();
13973 CallingConv NewCC = NewFT->getCallConv(), OldCC = OldFT->getCallConv();
13975 // If the calling conventions match, everything is fine
13976 if (NewCC == OldCC)
13979 // If the calling conventions mismatch because the new function is static,
13980 // suppress the calling convention mismatch error; the error about static
13981 // function override (err_static_overrides_virtual from
13982 // Sema::CheckFunctionDeclaration) is more clear.
13983 if (New->getStorageClass() == SC_Static)
13986 Diag(New->getLocation(),
13987 diag::err_conflicting_overriding_cc_attributes)
13988 << New->getDeclName() << New->getType() << Old->getType();
13989 Diag(Old->getLocation(), diag::note_overridden_virtual_function);
13993 bool Sema::CheckOverridingFunctionReturnType(const CXXMethodDecl *New,
13994 const CXXMethodDecl *Old) {
13995 QualType NewTy = New->getType()->getAs<FunctionType>()->getReturnType();
13996 QualType OldTy = Old->getType()->getAs<FunctionType>()->getReturnType();
13998 if (Context.hasSameType(NewTy, OldTy) ||
13999 NewTy->isDependentType() || OldTy->isDependentType())
14002 // Check if the return types are covariant
14003 QualType NewClassTy, OldClassTy;
14005 /// Both types must be pointers or references to classes.
14006 if (const PointerType *NewPT = NewTy->getAs<PointerType>()) {
14007 if (const PointerType *OldPT = OldTy->getAs<PointerType>()) {
14008 NewClassTy = NewPT->getPointeeType();
14009 OldClassTy = OldPT->getPointeeType();
14011 } else if (const ReferenceType *NewRT = NewTy->getAs<ReferenceType>()) {
14012 if (const ReferenceType *OldRT = OldTy->getAs<ReferenceType>()) {
14013 if (NewRT->getTypeClass() == OldRT->getTypeClass()) {
14014 NewClassTy = NewRT->getPointeeType();
14015 OldClassTy = OldRT->getPointeeType();
14020 // The return types aren't either both pointers or references to a class type.
14021 if (NewClassTy.isNull()) {
14022 Diag(New->getLocation(),
14023 diag::err_different_return_type_for_overriding_virtual_function)
14024 << New->getDeclName() << NewTy << OldTy
14025 << New->getReturnTypeSourceRange();
14026 Diag(Old->getLocation(), diag::note_overridden_virtual_function)
14027 << Old->getReturnTypeSourceRange();
14032 if (!Context.hasSameUnqualifiedType(NewClassTy, OldClassTy)) {
14033 // C++14 [class.virtual]p8:
14034 // If the class type in the covariant return type of D::f differs from
14035 // that of B::f, the class type in the return type of D::f shall be
14036 // complete at the point of declaration of D::f or shall be the class
14038 if (const RecordType *RT = NewClassTy->getAs<RecordType>()) {
14039 if (!RT->isBeingDefined() &&
14040 RequireCompleteType(New->getLocation(), NewClassTy,
14041 diag::err_covariant_return_incomplete,
14042 New->getDeclName()))
14046 // Check if the new class derives from the old class.
14047 if (!IsDerivedFrom(New->getLocation(), NewClassTy, OldClassTy)) {
14048 Diag(New->getLocation(), diag::err_covariant_return_not_derived)
14049 << New->getDeclName() << NewTy << OldTy
14050 << New->getReturnTypeSourceRange();
14051 Diag(Old->getLocation(), diag::note_overridden_virtual_function)
14052 << Old->getReturnTypeSourceRange();
14056 // Check if we the conversion from derived to base is valid.
14057 if (CheckDerivedToBaseConversion(
14058 NewClassTy, OldClassTy,
14059 diag::err_covariant_return_inaccessible_base,
14060 diag::err_covariant_return_ambiguous_derived_to_base_conv,
14061 New->getLocation(), New->getReturnTypeSourceRange(),
14062 New->getDeclName(), nullptr)) {
14063 // FIXME: this note won't trigger for delayed access control
14064 // diagnostics, and it's impossible to get an undelayed error
14065 // here from access control during the original parse because
14066 // the ParsingDeclSpec/ParsingDeclarator are still in scope.
14067 Diag(Old->getLocation(), diag::note_overridden_virtual_function)
14068 << Old->getReturnTypeSourceRange();
14073 // The qualifiers of the return types must be the same.
14074 if (NewTy.getLocalCVRQualifiers() != OldTy.getLocalCVRQualifiers()) {
14075 Diag(New->getLocation(),
14076 diag::err_covariant_return_type_different_qualifications)
14077 << New->getDeclName() << NewTy << OldTy
14078 << New->getReturnTypeSourceRange();
14079 Diag(Old->getLocation(), diag::note_overridden_virtual_function)
14080 << Old->getReturnTypeSourceRange();
14085 // The new class type must have the same or less qualifiers as the old type.
14086 if (NewClassTy.isMoreQualifiedThan(OldClassTy)) {
14087 Diag(New->getLocation(),
14088 diag::err_covariant_return_type_class_type_more_qualified)
14089 << New->getDeclName() << NewTy << OldTy
14090 << New->getReturnTypeSourceRange();
14091 Diag(Old->getLocation(), diag::note_overridden_virtual_function)
14092 << Old->getReturnTypeSourceRange();
14099 /// \brief Mark the given method pure.
14101 /// \param Method the method to be marked pure.
14103 /// \param InitRange the source range that covers the "0" initializer.
14104 bool Sema::CheckPureMethod(CXXMethodDecl *Method, SourceRange InitRange) {
14105 SourceLocation EndLoc = InitRange.getEnd();
14106 if (EndLoc.isValid())
14107 Method->setRangeEnd(EndLoc);
14109 if (Method->isVirtual() || Method->getParent()->isDependentContext()) {
14114 if (!Method->isInvalidDecl())
14115 Diag(Method->getLocation(), diag::err_non_virtual_pure)
14116 << Method->getDeclName() << InitRange;
14120 void Sema::ActOnPureSpecifier(Decl *D, SourceLocation ZeroLoc) {
14121 if (D->getFriendObjectKind())
14122 Diag(D->getLocation(), diag::err_pure_friend);
14123 else if (auto *M = dyn_cast<CXXMethodDecl>(D))
14124 CheckPureMethod(M, ZeroLoc);
14126 Diag(D->getLocation(), diag::err_illegal_initializer);
14129 /// \brief Determine whether the given declaration is a static data member.
14130 static bool isStaticDataMember(const Decl *D) {
14131 if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(D))
14132 return Var->isStaticDataMember();
14137 /// ActOnCXXEnterDeclInitializer - Invoked when we are about to parse
14138 /// an initializer for the out-of-line declaration 'Dcl'. The scope
14139 /// is a fresh scope pushed for just this purpose.
14141 /// After this method is called, according to [C++ 3.4.1p13], if 'Dcl' is a
14142 /// static data member of class X, names should be looked up in the scope of
14144 void Sema::ActOnCXXEnterDeclInitializer(Scope *S, Decl *D) {
14145 // If there is no declaration, there was an error parsing it.
14146 if (!D || D->isInvalidDecl())
14149 // We will always have a nested name specifier here, but this declaration
14150 // might not be out of line if the specifier names the current namespace:
14153 if (D->isOutOfLine())
14154 EnterDeclaratorContext(S, D->getDeclContext());
14156 // If we are parsing the initializer for a static data member, push a
14157 // new expression evaluation context that is associated with this static
14159 if (isStaticDataMember(D))
14160 PushExpressionEvaluationContext(PotentiallyEvaluated, D);
14163 /// ActOnCXXExitDeclInitializer - Invoked after we are finished parsing an
14164 /// initializer for the out-of-line declaration 'D'.
14165 void Sema::ActOnCXXExitDeclInitializer(Scope *S, Decl *D) {
14166 // If there is no declaration, there was an error parsing it.
14167 if (!D || D->isInvalidDecl())
14170 if (isStaticDataMember(D))
14171 PopExpressionEvaluationContext();
14173 if (D->isOutOfLine())
14174 ExitDeclaratorContext(S);
14177 /// ActOnCXXConditionDeclarationExpr - Parsed a condition declaration of a
14178 /// C++ if/switch/while/for statement.
14179 /// e.g: "if (int x = f()) {...}"
14180 DeclResult Sema::ActOnCXXConditionDeclaration(Scope *S, Declarator &D) {
14182 // The declarator shall not specify a function or an array.
14183 // The type-specifier-seq shall not contain typedef and shall not declare a
14184 // new class or enumeration.
14185 assert(D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
14186 "Parser allowed 'typedef' as storage class of condition decl.");
14188 Decl *Dcl = ActOnDeclarator(S, D);
14192 if (isa<FunctionDecl>(Dcl)) { // The declarator shall not specify a function.
14193 Diag(Dcl->getLocation(), diag::err_invalid_use_of_function_type)
14194 << D.getSourceRange();
14201 void Sema::LoadExternalVTableUses() {
14202 if (!ExternalSource)
14205 SmallVector<ExternalVTableUse, 4> VTables;
14206 ExternalSource->ReadUsedVTables(VTables);
14207 SmallVector<VTableUse, 4> NewUses;
14208 for (unsigned I = 0, N = VTables.size(); I != N; ++I) {
14209 llvm::DenseMap<CXXRecordDecl *, bool>::iterator Pos
14210 = VTablesUsed.find(VTables[I].Record);
14211 // Even if a definition wasn't required before, it may be required now.
14212 if (Pos != VTablesUsed.end()) {
14213 if (!Pos->second && VTables[I].DefinitionRequired)
14214 Pos->second = true;
14218 VTablesUsed[VTables[I].Record] = VTables[I].DefinitionRequired;
14219 NewUses.push_back(VTableUse(VTables[I].Record, VTables[I].Location));
14222 VTableUses.insert(VTableUses.begin(), NewUses.begin(), NewUses.end());
14225 void Sema::MarkVTableUsed(SourceLocation Loc, CXXRecordDecl *Class,
14226 bool DefinitionRequired) {
14227 // Ignore any vtable uses in unevaluated operands or for classes that do
14228 // not have a vtable.
14229 if (!Class->isDynamicClass() || Class->isDependentContext() ||
14230 CurContext->isDependentContext() || isUnevaluatedContext())
14233 // Try to insert this class into the map.
14234 LoadExternalVTableUses();
14235 Class = cast<CXXRecordDecl>(Class->getCanonicalDecl());
14236 std::pair<llvm::DenseMap<CXXRecordDecl *, bool>::iterator, bool>
14237 Pos = VTablesUsed.insert(std::make_pair(Class, DefinitionRequired));
14239 // If we already had an entry, check to see if we are promoting this vtable
14240 // to require a definition. If so, we need to reappend to the VTableUses
14241 // list, since we may have already processed the first entry.
14242 if (DefinitionRequired && !Pos.first->second) {
14243 Pos.first->second = true;
14245 // Otherwise, we can early exit.
14249 // The Microsoft ABI requires that we perform the destructor body
14250 // checks (i.e. operator delete() lookup) when the vtable is marked used, as
14251 // the deleting destructor is emitted with the vtable, not with the
14252 // destructor definition as in the Itanium ABI.
14253 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
14254 CXXDestructorDecl *DD = Class->getDestructor();
14255 if (DD && DD->isVirtual() && !DD->isDeleted()) {
14256 if (Class->hasUserDeclaredDestructor() && !DD->isDefined()) {
14257 // If this is an out-of-line declaration, marking it referenced will
14258 // not do anything. Manually call CheckDestructor to look up operator
14260 ContextRAII SavedContext(*this, DD);
14261 CheckDestructor(DD);
14263 MarkFunctionReferenced(Loc, Class->getDestructor());
14269 // Local classes need to have their virtual members marked
14270 // immediately. For all other classes, we mark their virtual members
14271 // at the end of the translation unit.
14272 if (Class->isLocalClass())
14273 MarkVirtualMembersReferenced(Loc, Class);
14275 VTableUses.push_back(std::make_pair(Class, Loc));
14278 bool Sema::DefineUsedVTables() {
14279 LoadExternalVTableUses();
14280 if (VTableUses.empty())
14283 // Note: The VTableUses vector could grow as a result of marking
14284 // the members of a class as "used", so we check the size each
14285 // time through the loop and prefer indices (which are stable) to
14286 // iterators (which are not).
14287 bool DefinedAnything = false;
14288 for (unsigned I = 0; I != VTableUses.size(); ++I) {
14289 CXXRecordDecl *Class = VTableUses[I].first->getDefinition();
14292 TemplateSpecializationKind ClassTSK =
14293 Class->getTemplateSpecializationKind();
14295 SourceLocation Loc = VTableUses[I].second;
14297 bool DefineVTable = true;
14299 // If this class has a key function, but that key function is
14300 // defined in another translation unit, we don't need to emit the
14301 // vtable even though we're using it.
14302 const CXXMethodDecl *KeyFunction = Context.getCurrentKeyFunction(Class);
14303 if (KeyFunction && !KeyFunction->hasBody()) {
14304 // The key function is in another translation unit.
14305 DefineVTable = false;
14306 TemplateSpecializationKind TSK =
14307 KeyFunction->getTemplateSpecializationKind();
14308 assert(TSK != TSK_ExplicitInstantiationDefinition &&
14309 TSK != TSK_ImplicitInstantiation &&
14310 "Instantiations don't have key functions");
14312 } else if (!KeyFunction) {
14313 // If we have a class with no key function that is the subject
14314 // of an explicit instantiation declaration, suppress the
14315 // vtable; it will live with the explicit instantiation
14317 bool IsExplicitInstantiationDeclaration =
14318 ClassTSK == TSK_ExplicitInstantiationDeclaration;
14319 for (auto R : Class->redecls()) {
14320 TemplateSpecializationKind TSK
14321 = cast<CXXRecordDecl>(R)->getTemplateSpecializationKind();
14322 if (TSK == TSK_ExplicitInstantiationDeclaration)
14323 IsExplicitInstantiationDeclaration = true;
14324 else if (TSK == TSK_ExplicitInstantiationDefinition) {
14325 IsExplicitInstantiationDeclaration = false;
14330 if (IsExplicitInstantiationDeclaration)
14331 DefineVTable = false;
14334 // The exception specifications for all virtual members may be needed even
14335 // if we are not providing an authoritative form of the vtable in this TU.
14336 // We may choose to emit it available_externally anyway.
14337 if (!DefineVTable) {
14338 MarkVirtualMemberExceptionSpecsNeeded(Loc, Class);
14342 // Mark all of the virtual members of this class as referenced, so
14343 // that we can build a vtable. Then, tell the AST consumer that a
14344 // vtable for this class is required.
14345 DefinedAnything = true;
14346 MarkVirtualMembersReferenced(Loc, Class);
14347 CXXRecordDecl *Canonical = cast<CXXRecordDecl>(Class->getCanonicalDecl());
14348 if (VTablesUsed[Canonical])
14349 Consumer.HandleVTable(Class);
14351 // Warn if we're emitting a weak vtable. The vtable will be weak if there is
14352 // no key function or the key function is inlined. Don't warn in C++ ABIs
14353 // that lack key functions, since the user won't be able to make one.
14354 if (Context.getTargetInfo().getCXXABI().hasKeyFunctions() &&
14355 Class->isExternallyVisible() && ClassTSK != TSK_ImplicitInstantiation) {
14356 const FunctionDecl *KeyFunctionDef = nullptr;
14357 if (!KeyFunction || (KeyFunction->hasBody(KeyFunctionDef) &&
14358 KeyFunctionDef->isInlined())) {
14359 Diag(Class->getLocation(),
14360 ClassTSK == TSK_ExplicitInstantiationDefinition
14361 ? diag::warn_weak_template_vtable
14362 : diag::warn_weak_vtable)
14367 VTableUses.clear();
14369 return DefinedAnything;
14372 void Sema::MarkVirtualMemberExceptionSpecsNeeded(SourceLocation Loc,
14373 const CXXRecordDecl *RD) {
14374 for (const auto *I : RD->methods())
14375 if (I->isVirtual() && !I->isPure())
14376 ResolveExceptionSpec(Loc, I->getType()->castAs<FunctionProtoType>());
14379 void Sema::MarkVirtualMembersReferenced(SourceLocation Loc,
14380 const CXXRecordDecl *RD) {
14381 // Mark all functions which will appear in RD's vtable as used.
14382 CXXFinalOverriderMap FinalOverriders;
14383 RD->getFinalOverriders(FinalOverriders);
14384 for (CXXFinalOverriderMap::const_iterator I = FinalOverriders.begin(),
14385 E = FinalOverriders.end();
14387 for (OverridingMethods::const_iterator OI = I->second.begin(),
14388 OE = I->second.end();
14390 assert(OI->second.size() > 0 && "no final overrider");
14391 CXXMethodDecl *Overrider = OI->second.front().Method;
14393 // C++ [basic.def.odr]p2:
14394 // [...] A virtual member function is used if it is not pure. [...]
14395 if (!Overrider->isPure())
14396 MarkFunctionReferenced(Loc, Overrider);
14400 // Only classes that have virtual bases need a VTT.
14401 if (RD->getNumVBases() == 0)
14404 for (const auto &I : RD->bases()) {
14405 const CXXRecordDecl *Base =
14406 cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
14407 if (Base->getNumVBases() == 0)
14409 MarkVirtualMembersReferenced(Loc, Base);
14413 /// SetIvarInitializers - This routine builds initialization ASTs for the
14414 /// Objective-C implementation whose ivars need be initialized.
14415 void Sema::SetIvarInitializers(ObjCImplementationDecl *ObjCImplementation) {
14416 if (!getLangOpts().CPlusPlus)
14418 if (ObjCInterfaceDecl *OID = ObjCImplementation->getClassInterface()) {
14419 SmallVector<ObjCIvarDecl*, 8> ivars;
14420 CollectIvarsToConstructOrDestruct(OID, ivars);
14423 SmallVector<CXXCtorInitializer*, 32> AllToInit;
14424 for (unsigned i = 0; i < ivars.size(); i++) {
14425 FieldDecl *Field = ivars[i];
14426 if (Field->isInvalidDecl())
14429 CXXCtorInitializer *Member;
14430 InitializedEntity InitEntity = InitializedEntity::InitializeMember(Field);
14431 InitializationKind InitKind =
14432 InitializationKind::CreateDefault(ObjCImplementation->getLocation());
14434 InitializationSequence InitSeq(*this, InitEntity, InitKind, None);
14435 ExprResult MemberInit =
14436 InitSeq.Perform(*this, InitEntity, InitKind, None);
14437 MemberInit = MaybeCreateExprWithCleanups(MemberInit);
14438 // Note, MemberInit could actually come back empty if no initialization
14439 // is required (e.g., because it would call a trivial default constructor)
14440 if (!MemberInit.get() || MemberInit.isInvalid())
14444 new (Context) CXXCtorInitializer(Context, Field, SourceLocation(),
14446 MemberInit.getAs<Expr>(),
14448 AllToInit.push_back(Member);
14450 // Be sure that the destructor is accessible and is marked as referenced.
14451 if (const RecordType *RecordTy =
14452 Context.getBaseElementType(Field->getType())
14453 ->getAs<RecordType>()) {
14454 CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl());
14455 if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
14456 MarkFunctionReferenced(Field->getLocation(), Destructor);
14457 CheckDestructorAccess(Field->getLocation(), Destructor,
14458 PDiag(diag::err_access_dtor_ivar)
14459 << Context.getBaseElementType(Field->getType()));
14463 ObjCImplementation->setIvarInitializers(Context,
14464 AllToInit.data(), AllToInit.size());
14469 void DelegatingCycleHelper(CXXConstructorDecl* Ctor,
14470 llvm::SmallSet<CXXConstructorDecl*, 4> &Valid,
14471 llvm::SmallSet<CXXConstructorDecl*, 4> &Invalid,
14472 llvm::SmallSet<CXXConstructorDecl*, 4> &Current,
14474 if (Ctor->isInvalidDecl())
14477 CXXConstructorDecl *Target = Ctor->getTargetConstructor();
14479 // Target may not be determinable yet, for instance if this is a dependent
14480 // call in an uninstantiated template.
14482 const FunctionDecl *FNTarget = nullptr;
14483 (void)Target->hasBody(FNTarget);
14484 Target = const_cast<CXXConstructorDecl*>(
14485 cast_or_null<CXXConstructorDecl>(FNTarget));
14488 CXXConstructorDecl *Canonical = Ctor->getCanonicalDecl(),
14489 // Avoid dereferencing a null pointer here.
14490 *TCanonical = Target? Target->getCanonicalDecl() : nullptr;
14492 if (!Current.insert(Canonical).second)
14495 // We know that beyond here, we aren't chaining into a cycle.
14496 if (!Target || !Target->isDelegatingConstructor() ||
14497 Target->isInvalidDecl() || Valid.count(TCanonical)) {
14498 Valid.insert(Current.begin(), Current.end());
14500 // We've hit a cycle.
14501 } else if (TCanonical == Canonical || Invalid.count(TCanonical) ||
14502 Current.count(TCanonical)) {
14503 // If we haven't diagnosed this cycle yet, do so now.
14504 if (!Invalid.count(TCanonical)) {
14505 S.Diag((*Ctor->init_begin())->getSourceLocation(),
14506 diag::warn_delegating_ctor_cycle)
14509 // Don't add a note for a function delegating directly to itself.
14510 if (TCanonical != Canonical)
14511 S.Diag(Target->getLocation(), diag::note_it_delegates_to);
14513 CXXConstructorDecl *C = Target;
14514 while (C->getCanonicalDecl() != Canonical) {
14515 const FunctionDecl *FNTarget = nullptr;
14516 (void)C->getTargetConstructor()->hasBody(FNTarget);
14517 assert(FNTarget && "Ctor cycle through bodiless function");
14519 C = const_cast<CXXConstructorDecl*>(
14520 cast<CXXConstructorDecl>(FNTarget));
14521 S.Diag(C->getLocation(), diag::note_which_delegates_to);
14525 Invalid.insert(Current.begin(), Current.end());
14528 DelegatingCycleHelper(Target, Valid, Invalid, Current, S);
14533 void Sema::CheckDelegatingCtorCycles() {
14534 llvm::SmallSet<CXXConstructorDecl*, 4> Valid, Invalid, Current;
14536 for (DelegatingCtorDeclsType::iterator
14537 I = DelegatingCtorDecls.begin(ExternalSource),
14538 E = DelegatingCtorDecls.end();
14540 DelegatingCycleHelper(*I, Valid, Invalid, Current, *this);
14542 for (llvm::SmallSet<CXXConstructorDecl *, 4>::iterator CI = Invalid.begin(),
14543 CE = Invalid.end();
14545 (*CI)->setInvalidDecl();
14549 /// \brief AST visitor that finds references to the 'this' expression.
14550 class FindCXXThisExpr : public RecursiveASTVisitor<FindCXXThisExpr> {
14554 explicit FindCXXThisExpr(Sema &S) : S(S) { }
14556 bool VisitCXXThisExpr(CXXThisExpr *E) {
14557 S.Diag(E->getLocation(), diag::err_this_static_member_func)
14558 << E->isImplicit();
14564 bool Sema::checkThisInStaticMemberFunctionType(CXXMethodDecl *Method) {
14565 TypeSourceInfo *TSInfo = Method->getTypeSourceInfo();
14569 TypeLoc TL = TSInfo->getTypeLoc();
14570 FunctionProtoTypeLoc ProtoTL = TL.getAs<FunctionProtoTypeLoc>();
14574 // C++11 [expr.prim.general]p3:
14575 // [The expression this] shall not appear before the optional
14576 // cv-qualifier-seq and it shall not appear within the declaration of a
14577 // static member function (although its type and value category are defined
14578 // within a static member function as they are within a non-static member
14579 // function). [ Note: this is because declaration matching does not occur
14580 // until the complete declarator is known. - end note ]
14581 const FunctionProtoType *Proto = ProtoTL.getTypePtr();
14582 FindCXXThisExpr Finder(*this);
14584 // If the return type came after the cv-qualifier-seq, check it now.
14585 if (Proto->hasTrailingReturn() &&
14586 !Finder.TraverseTypeLoc(ProtoTL.getReturnLoc()))
14589 // Check the exception specification.
14590 if (checkThisInStaticMemberFunctionExceptionSpec(Method))
14593 return checkThisInStaticMemberFunctionAttributes(Method);
14596 bool Sema::checkThisInStaticMemberFunctionExceptionSpec(CXXMethodDecl *Method) {
14597 TypeSourceInfo *TSInfo = Method->getTypeSourceInfo();
14601 TypeLoc TL = TSInfo->getTypeLoc();
14602 FunctionProtoTypeLoc ProtoTL = TL.getAs<FunctionProtoTypeLoc>();
14606 const FunctionProtoType *Proto = ProtoTL.getTypePtr();
14607 FindCXXThisExpr Finder(*this);
14609 switch (Proto->getExceptionSpecType()) {
14611 case EST_Uninstantiated:
14612 case EST_Unevaluated:
14613 case EST_BasicNoexcept:
14614 case EST_DynamicNone:
14619 case EST_ComputedNoexcept:
14620 if (!Finder.TraverseStmt(Proto->getNoexceptExpr()))
14624 for (const auto &E : Proto->exceptions()) {
14625 if (!Finder.TraverseType(E))
14634 bool Sema::checkThisInStaticMemberFunctionAttributes(CXXMethodDecl *Method) {
14635 FindCXXThisExpr Finder(*this);
14637 // Check attributes.
14638 for (const auto *A : Method->attrs()) {
14639 // FIXME: This should be emitted by tblgen.
14640 Expr *Arg = nullptr;
14641 ArrayRef<Expr *> Args;
14642 if (const auto *G = dyn_cast<GuardedByAttr>(A))
14644 else if (const auto *G = dyn_cast<PtGuardedByAttr>(A))
14646 else if (const auto *AA = dyn_cast<AcquiredAfterAttr>(A))
14647 Args = llvm::makeArrayRef(AA->args_begin(), AA->args_size());
14648 else if (const auto *AB = dyn_cast<AcquiredBeforeAttr>(A))
14649 Args = llvm::makeArrayRef(AB->args_begin(), AB->args_size());
14650 else if (const auto *ETLF = dyn_cast<ExclusiveTrylockFunctionAttr>(A)) {
14651 Arg = ETLF->getSuccessValue();
14652 Args = llvm::makeArrayRef(ETLF->args_begin(), ETLF->args_size());
14653 } else if (const auto *STLF = dyn_cast<SharedTrylockFunctionAttr>(A)) {
14654 Arg = STLF->getSuccessValue();
14655 Args = llvm::makeArrayRef(STLF->args_begin(), STLF->args_size());
14656 } else if (const auto *LR = dyn_cast<LockReturnedAttr>(A))
14657 Arg = LR->getArg();
14658 else if (const auto *LE = dyn_cast<LocksExcludedAttr>(A))
14659 Args = llvm::makeArrayRef(LE->args_begin(), LE->args_size());
14660 else if (const auto *RC = dyn_cast<RequiresCapabilityAttr>(A))
14661 Args = llvm::makeArrayRef(RC->args_begin(), RC->args_size());
14662 else if (const auto *AC = dyn_cast<AcquireCapabilityAttr>(A))
14663 Args = llvm::makeArrayRef(AC->args_begin(), AC->args_size());
14664 else if (const auto *AC = dyn_cast<TryAcquireCapabilityAttr>(A))
14665 Args = llvm::makeArrayRef(AC->args_begin(), AC->args_size());
14666 else if (const auto *RC = dyn_cast<ReleaseCapabilityAttr>(A))
14667 Args = llvm::makeArrayRef(RC->args_begin(), RC->args_size());
14669 if (Arg && !Finder.TraverseStmt(Arg))
14672 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
14673 if (!Finder.TraverseStmt(Args[I]))
14681 void Sema::checkExceptionSpecification(
14682 bool IsTopLevel, ExceptionSpecificationType EST,
14683 ArrayRef<ParsedType> DynamicExceptions,
14684 ArrayRef<SourceRange> DynamicExceptionRanges, Expr *NoexceptExpr,
14685 SmallVectorImpl<QualType> &Exceptions,
14686 FunctionProtoType::ExceptionSpecInfo &ESI) {
14687 Exceptions.clear();
14689 if (EST == EST_Dynamic) {
14690 Exceptions.reserve(DynamicExceptions.size());
14691 for (unsigned ei = 0, ee = DynamicExceptions.size(); ei != ee; ++ei) {
14692 // FIXME: Preserve type source info.
14693 QualType ET = GetTypeFromParser(DynamicExceptions[ei]);
14696 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
14697 collectUnexpandedParameterPacks(ET, Unexpanded);
14698 if (!Unexpanded.empty()) {
14699 DiagnoseUnexpandedParameterPacks(
14700 DynamicExceptionRanges[ei].getBegin(), UPPC_ExceptionType,
14706 // Check that the type is valid for an exception spec, and
14708 if (!CheckSpecifiedExceptionType(ET, DynamicExceptionRanges[ei]))
14709 Exceptions.push_back(ET);
14711 ESI.Exceptions = Exceptions;
14715 if (EST == EST_ComputedNoexcept) {
14716 // If an error occurred, there's no expression here.
14717 if (NoexceptExpr) {
14718 assert((NoexceptExpr->isTypeDependent() ||
14719 NoexceptExpr->getType()->getCanonicalTypeUnqualified() ==
14721 "Parser should have made sure that the expression is boolean");
14722 if (IsTopLevel && NoexceptExpr &&
14723 DiagnoseUnexpandedParameterPack(NoexceptExpr)) {
14724 ESI.Type = EST_BasicNoexcept;
14728 if (!NoexceptExpr->isValueDependent())
14729 NoexceptExpr = VerifyIntegerConstantExpression(NoexceptExpr, nullptr,
14730 diag::err_noexcept_needs_constant_expression,
14731 /*AllowFold*/ false).get();
14732 ESI.NoexceptExpr = NoexceptExpr;
14738 void Sema::actOnDelayedExceptionSpecification(Decl *MethodD,
14739 ExceptionSpecificationType EST,
14740 SourceRange SpecificationRange,
14741 ArrayRef<ParsedType> DynamicExceptions,
14742 ArrayRef<SourceRange> DynamicExceptionRanges,
14743 Expr *NoexceptExpr) {
14747 // Dig out the method we're referring to.
14748 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(MethodD))
14749 MethodD = FunTmpl->getTemplatedDecl();
14751 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(MethodD);
14755 // Check the exception specification.
14756 llvm::SmallVector<QualType, 4> Exceptions;
14757 FunctionProtoType::ExceptionSpecInfo ESI;
14758 checkExceptionSpecification(/*IsTopLevel*/true, EST, DynamicExceptions,
14759 DynamicExceptionRanges, NoexceptExpr, Exceptions,
14762 // Update the exception specification on the function type.
14763 Context.adjustExceptionSpec(Method, ESI, /*AsWritten*/true);
14765 if (Method->isStatic())
14766 checkThisInStaticMemberFunctionExceptionSpec(Method);
14768 if (Method->isVirtual()) {
14769 // Check overrides, which we previously had to delay.
14770 for (CXXMethodDecl::method_iterator O = Method->begin_overridden_methods(),
14771 OEnd = Method->end_overridden_methods();
14773 CheckOverridingFunctionExceptionSpec(Method, *O);
14777 /// HandleMSProperty - Analyze a __delcspec(property) field of a C++ class.
14779 MSPropertyDecl *Sema::HandleMSProperty(Scope *S, RecordDecl *Record,
14780 SourceLocation DeclStart,
14781 Declarator &D, Expr *BitWidth,
14782 InClassInitStyle InitStyle,
14783 AccessSpecifier AS,
14784 AttributeList *MSPropertyAttr) {
14785 IdentifierInfo *II = D.getIdentifier();
14787 Diag(DeclStart, diag::err_anonymous_property);
14790 SourceLocation Loc = D.getIdentifierLoc();
14792 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
14793 QualType T = TInfo->getType();
14794 if (getLangOpts().CPlusPlus) {
14795 CheckExtraCXXDefaultArguments(D);
14797 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
14798 UPPC_DataMemberType)) {
14799 D.setInvalidType();
14801 TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
14805 DiagnoseFunctionSpecifiers(D.getDeclSpec());
14807 if (D.getDeclSpec().isInlineSpecified())
14808 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
14809 << getLangOpts().CPlusPlus1z;
14810 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
14811 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
14812 diag::err_invalid_thread)
14813 << DeclSpec::getSpecifierName(TSCS);
14815 // Check to see if this name was declared as a member previously
14816 NamedDecl *PrevDecl = nullptr;
14817 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration);
14818 LookupName(Previous, S);
14819 switch (Previous.getResultKind()) {
14820 case LookupResult::Found:
14821 case LookupResult::FoundUnresolvedValue:
14822 PrevDecl = Previous.getAsSingle<NamedDecl>();
14825 case LookupResult::FoundOverloaded:
14826 PrevDecl = Previous.getRepresentativeDecl();
14829 case LookupResult::NotFound:
14830 case LookupResult::NotFoundInCurrentInstantiation:
14831 case LookupResult::Ambiguous:
14835 if (PrevDecl && PrevDecl->isTemplateParameter()) {
14836 // Maybe we will complain about the shadowed template parameter.
14837 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
14838 // Just pretend that we didn't see the previous declaration.
14839 PrevDecl = nullptr;
14842 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
14843 PrevDecl = nullptr;
14845 SourceLocation TSSL = D.getLocStart();
14846 const AttributeList::PropertyData &Data = MSPropertyAttr->getPropertyData();
14847 MSPropertyDecl *NewPD = MSPropertyDecl::Create(
14848 Context, Record, Loc, II, T, TInfo, TSSL, Data.GetterId, Data.SetterId);
14849 ProcessDeclAttributes(TUScope, NewPD, D);
14850 NewPD->setAccess(AS);
14852 if (NewPD->isInvalidDecl())
14853 Record->setInvalidDecl();
14855 if (D.getDeclSpec().isModulePrivateSpecified())
14856 NewPD->setModulePrivate();
14858 if (NewPD->isInvalidDecl() && PrevDecl) {
14859 // Don't introduce NewFD into scope; there's already something
14860 // with the same name in the same scope.
14862 PushOnScopeChains(NewPD, S);
14864 Record->addDecl(NewPD);