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 // sufficient, 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 // FIXME: It's not clear what should happen if multiple declarations of a
651 // deduction guide have different explicitness. For now at least we simply
652 // reject any case where the explicitness changes.
653 auto *NewGuide = dyn_cast<CXXDeductionGuideDecl>(New);
654 if (NewGuide && NewGuide->isExplicitSpecified() !=
655 cast<CXXDeductionGuideDecl>(Old)->isExplicitSpecified()) {
656 Diag(New->getLocation(), diag::err_deduction_guide_explicit_mismatch)
657 << NewGuide->isExplicitSpecified();
658 Diag(Old->getLocation(), diag::note_previous_declaration);
661 // C++11 [dcl.fct.default]p4: If a friend declaration specifies a default
662 // argument expression, that declaration shall be a definition and shall be
663 // the only declaration of the function or function template in the
665 if (Old->getFriendObjectKind() == Decl::FOK_Undeclared &&
666 functionDeclHasDefaultArgument(Old)) {
667 Diag(New->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
668 Diag(Old->getLocation(), diag::note_previous_declaration);
676 Sema::ActOnDecompositionDeclarator(Scope *S, Declarator &D,
677 MultiTemplateParamsArg TemplateParamLists) {
678 assert(D.isDecompositionDeclarator());
679 const DecompositionDeclarator &Decomp = D.getDecompositionDeclarator();
681 // The syntax only allows a decomposition declarator as a simple-declaration
682 // or a for-range-declaration, but we parse it in more cases than that.
683 if (!D.mayHaveDecompositionDeclarator()) {
684 Diag(Decomp.getLSquareLoc(), diag::err_decomp_decl_context)
685 << Decomp.getSourceRange();
689 if (!TemplateParamLists.empty()) {
690 // FIXME: There's no rule against this, but there are also no rules that
691 // would actually make it usable, so we reject it for now.
692 Diag(TemplateParamLists.front()->getTemplateLoc(),
693 diag::err_decomp_decl_template);
697 Diag(Decomp.getLSquareLoc(), getLangOpts().CPlusPlus1z
698 ? diag::warn_cxx14_compat_decomp_decl
699 : diag::ext_decomp_decl)
700 << Decomp.getSourceRange();
702 // The semantic context is always just the current context.
703 DeclContext *const DC = CurContext;
705 // C++1z [dcl.dcl]/8:
706 // The decl-specifier-seq shall contain only the type-specifier auto
707 // and cv-qualifiers.
708 auto &DS = D.getDeclSpec();
710 SmallVector<StringRef, 8> BadSpecifiers;
711 SmallVector<SourceLocation, 8> BadSpecifierLocs;
712 if (auto SCS = DS.getStorageClassSpec()) {
713 BadSpecifiers.push_back(DeclSpec::getSpecifierName(SCS));
714 BadSpecifierLocs.push_back(DS.getStorageClassSpecLoc());
716 if (auto TSCS = DS.getThreadStorageClassSpec()) {
717 BadSpecifiers.push_back(DeclSpec::getSpecifierName(TSCS));
718 BadSpecifierLocs.push_back(DS.getThreadStorageClassSpecLoc());
720 if (DS.isConstexprSpecified()) {
721 BadSpecifiers.push_back("constexpr");
722 BadSpecifierLocs.push_back(DS.getConstexprSpecLoc());
724 if (DS.isInlineSpecified()) {
725 BadSpecifiers.push_back("inline");
726 BadSpecifierLocs.push_back(DS.getInlineSpecLoc());
728 if (!BadSpecifiers.empty()) {
729 auto &&Err = Diag(BadSpecifierLocs.front(), diag::err_decomp_decl_spec);
730 Err << (int)BadSpecifiers.size()
731 << llvm::join(BadSpecifiers.begin(), BadSpecifiers.end(), " ");
732 // Don't add FixItHints to remove the specifiers; we do still respect
733 // them when building the underlying variable.
734 for (auto Loc : BadSpecifierLocs)
735 Err << SourceRange(Loc, Loc);
737 // We can't recover from it being declared as a typedef.
738 if (DS.getStorageClassSpec() == DeclSpec::SCS_typedef)
742 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
743 QualType R = TInfo->getType();
745 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
746 UPPC_DeclarationType))
749 // The syntax only allows a single ref-qualifier prior to the decomposition
750 // declarator. No other declarator chunks are permitted. Also check the type
752 if (DS.getTypeSpecType() != DeclSpec::TST_auto ||
753 D.hasGroupingParens() || D.getNumTypeObjects() > 1 ||
754 (D.getNumTypeObjects() == 1 &&
755 D.getTypeObject(0).Kind != DeclaratorChunk::Reference)) {
756 Diag(Decomp.getLSquareLoc(),
757 (D.hasGroupingParens() ||
758 (D.getNumTypeObjects() &&
759 D.getTypeObject(0).Kind == DeclaratorChunk::Paren))
760 ? diag::err_decomp_decl_parens
761 : diag::err_decomp_decl_type)
764 // In most cases, there's no actual problem with an explicitly-specified
765 // type, but a function type won't work here, and ActOnVariableDeclarator
766 // shouldn't be called for such a type.
767 if (R->isFunctionType())
771 // Build the BindingDecls.
772 SmallVector<BindingDecl*, 8> Bindings;
774 // Build the BindingDecls.
775 for (auto &B : D.getDecompositionDeclarator().bindings()) {
776 // Check for name conflicts.
777 DeclarationNameInfo NameInfo(B.Name, B.NameLoc);
778 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
780 LookupName(Previous, S,
781 /*CreateBuiltins*/DC->getRedeclContext()->isTranslationUnit());
783 // It's not permitted to shadow a template parameter name.
784 if (Previous.isSingleResult() &&
785 Previous.getFoundDecl()->isTemplateParameter()) {
786 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(),
787 Previous.getFoundDecl());
791 bool ConsiderLinkage = DC->isFunctionOrMethod() &&
792 DS.getStorageClassSpec() == DeclSpec::SCS_extern;
793 FilterLookupForScope(Previous, DC, S, ConsiderLinkage,
794 /*AllowInlineNamespace*/false);
795 if (!Previous.empty()) {
796 auto *Old = Previous.getRepresentativeDecl();
797 Diag(B.NameLoc, diag::err_redefinition) << B.Name;
798 Diag(Old->getLocation(), diag::note_previous_definition);
801 auto *BD = BindingDecl::Create(Context, DC, B.NameLoc, B.Name);
802 PushOnScopeChains(BD, S, true);
803 Bindings.push_back(BD);
804 ParsingInitForAutoVars.insert(BD);
807 // There are no prior lookup results for the variable itself, because it
809 DeclarationNameInfo NameInfo((IdentifierInfo *)nullptr,
810 Decomp.getLSquareLoc());
811 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, ForRedeclaration);
813 // Build the variable that holds the non-decomposed object.
814 bool AddToScope = true;
816 ActOnVariableDeclarator(S, D, DC, TInfo, Previous,
817 MultiTemplateParamsArg(), AddToScope, Bindings);
818 CurContext->addHiddenDecl(New);
820 if (isInOpenMPDeclareTargetContext())
821 checkDeclIsAllowedInOpenMPTarget(nullptr, New);
826 static bool checkSimpleDecomposition(
827 Sema &S, ArrayRef<BindingDecl *> Bindings, ValueDecl *Src,
828 QualType DecompType, const llvm::APSInt &NumElems, QualType ElemType,
829 llvm::function_ref<ExprResult(SourceLocation, Expr *, unsigned)> GetInit) {
830 if ((int64_t)Bindings.size() != NumElems) {
831 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
832 << DecompType << (unsigned)Bindings.size() << NumElems.toString(10)
833 << (NumElems < Bindings.size());
838 for (auto *B : Bindings) {
839 SourceLocation Loc = B->getLocation();
840 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
843 E = GetInit(Loc, E.get(), I++);
846 B->setBinding(ElemType, E.get());
852 static bool checkArrayLikeDecomposition(Sema &S,
853 ArrayRef<BindingDecl *> Bindings,
854 ValueDecl *Src, QualType DecompType,
855 const llvm::APSInt &NumElems,
857 return checkSimpleDecomposition(
858 S, Bindings, Src, DecompType, NumElems, ElemType,
859 [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
860 ExprResult E = S.ActOnIntegerConstant(Loc, I);
863 return S.CreateBuiltinArraySubscriptExpr(Base, Loc, E.get(), Loc);
867 static bool checkArrayDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
868 ValueDecl *Src, QualType DecompType,
869 const ConstantArrayType *CAT) {
870 return checkArrayLikeDecomposition(S, Bindings, Src, DecompType,
871 llvm::APSInt(CAT->getSize()),
872 CAT->getElementType());
875 static bool checkVectorDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
876 ValueDecl *Src, QualType DecompType,
877 const VectorType *VT) {
878 return checkArrayLikeDecomposition(
879 S, Bindings, Src, DecompType, llvm::APSInt::get(VT->getNumElements()),
880 S.Context.getQualifiedType(VT->getElementType(),
881 DecompType.getQualifiers()));
884 static bool checkComplexDecomposition(Sema &S,
885 ArrayRef<BindingDecl *> Bindings,
886 ValueDecl *Src, QualType DecompType,
887 const ComplexType *CT) {
888 return checkSimpleDecomposition(
889 S, Bindings, Src, DecompType, llvm::APSInt::get(2),
890 S.Context.getQualifiedType(CT->getElementType(),
891 DecompType.getQualifiers()),
892 [&](SourceLocation Loc, Expr *Base, unsigned I) -> ExprResult {
893 return S.CreateBuiltinUnaryOp(Loc, I ? UO_Imag : UO_Real, Base);
897 static std::string printTemplateArgs(const PrintingPolicy &PrintingPolicy,
898 TemplateArgumentListInfo &Args) {
900 llvm::raw_svector_ostream OS(SS);
902 for (auto &Arg : Args.arguments()) {
905 Arg.getArgument().print(PrintingPolicy, OS);
911 static bool lookupStdTypeTraitMember(Sema &S, LookupResult &TraitMemberLookup,
912 SourceLocation Loc, StringRef Trait,
913 TemplateArgumentListInfo &Args,
915 auto DiagnoseMissing = [&] {
917 S.Diag(Loc, DiagID) << printTemplateArgs(S.Context.getPrintingPolicy(),
922 // FIXME: Factor out duplication with lookupPromiseType in SemaCoroutine.
923 NamespaceDecl *Std = S.getStdNamespace();
925 return DiagnoseMissing();
927 // Look up the trait itself, within namespace std. We can diagnose various
928 // problems with this lookup even if we've been asked to not diagnose a
929 // missing specialization, because this can only fail if the user has been
930 // declaring their own names in namespace std or we don't support the
931 // standard library implementation in use.
932 LookupResult Result(S, &S.PP.getIdentifierTable().get(Trait),
933 Loc, Sema::LookupOrdinaryName);
934 if (!S.LookupQualifiedName(Result, Std))
935 return DiagnoseMissing();
936 if (Result.isAmbiguous())
939 ClassTemplateDecl *TraitTD = Result.getAsSingle<ClassTemplateDecl>();
941 Result.suppressDiagnostics();
942 NamedDecl *Found = *Result.begin();
943 S.Diag(Loc, diag::err_std_type_trait_not_class_template) << Trait;
944 S.Diag(Found->getLocation(), diag::note_declared_at);
948 // Build the template-id.
949 QualType TraitTy = S.CheckTemplateIdType(TemplateName(TraitTD), Loc, Args);
950 if (TraitTy.isNull())
952 if (!S.isCompleteType(Loc, TraitTy)) {
954 S.RequireCompleteType(
955 Loc, TraitTy, DiagID,
956 printTemplateArgs(S.Context.getPrintingPolicy(), Args));
960 CXXRecordDecl *RD = TraitTy->getAsCXXRecordDecl();
961 assert(RD && "specialization of class template is not a class?");
963 // Look up the member of the trait type.
964 S.LookupQualifiedName(TraitMemberLookup, RD);
965 return TraitMemberLookup.isAmbiguous();
968 static TemplateArgumentLoc
969 getTrivialIntegralTemplateArgument(Sema &S, SourceLocation Loc, QualType T,
971 TemplateArgument Arg(S.Context, S.Context.MakeIntValue(I, T), T);
972 return S.getTrivialTemplateArgumentLoc(Arg, T, Loc);
975 static TemplateArgumentLoc
976 getTrivialTypeTemplateArgument(Sema &S, SourceLocation Loc, QualType T) {
977 return S.getTrivialTemplateArgumentLoc(TemplateArgument(T), QualType(), Loc);
980 namespace { enum class IsTupleLike { TupleLike, NotTupleLike, Error }; }
982 static IsTupleLike isTupleLike(Sema &S, SourceLocation Loc, QualType T,
983 llvm::APSInt &Size) {
984 EnterExpressionEvaluationContext ContextRAII(
985 S, Sema::ExpressionEvaluationContext::ConstantEvaluated);
987 DeclarationName Value = S.PP.getIdentifierInfo("value");
988 LookupResult R(S, Value, Loc, Sema::LookupOrdinaryName);
990 // Form template argument list for tuple_size<T>.
991 TemplateArgumentListInfo Args(Loc, Loc);
992 Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
994 // If there's no tuple_size specialization, it's not tuple-like.
995 if (lookupStdTypeTraitMember(S, R, Loc, "tuple_size", Args, /*DiagID*/0))
996 return IsTupleLike::NotTupleLike;
998 // If we get this far, we've committed to the tuple interpretation, but
999 // we can still fail if there actually isn't a usable ::value.
1001 struct ICEDiagnoser : Sema::VerifyICEDiagnoser {
1003 TemplateArgumentListInfo &Args;
1004 ICEDiagnoser(LookupResult &R, TemplateArgumentListInfo &Args)
1005 : R(R), Args(Args) {}
1006 void diagnoseNotICE(Sema &S, SourceLocation Loc, SourceRange SR) {
1007 S.Diag(Loc, diag::err_decomp_decl_std_tuple_size_not_constant)
1008 << printTemplateArgs(S.Context.getPrintingPolicy(), Args);
1010 } Diagnoser(R, Args);
1013 Diagnoser.diagnoseNotICE(S, Loc, SourceRange());
1014 return IsTupleLike::Error;
1018 S.BuildDeclarationNameExpr(CXXScopeSpec(), R, /*NeedsADL*/false);
1020 return IsTupleLike::Error;
1022 E = S.VerifyIntegerConstantExpression(E.get(), &Size, Diagnoser, false);
1024 return IsTupleLike::Error;
1026 return IsTupleLike::TupleLike;
1029 /// \return std::tuple_element<I, T>::type.
1030 static QualType getTupleLikeElementType(Sema &S, SourceLocation Loc,
1031 unsigned I, QualType T) {
1032 // Form template argument list for tuple_element<I, T>.
1033 TemplateArgumentListInfo Args(Loc, Loc);
1035 getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
1036 Args.addArgument(getTrivialTypeTemplateArgument(S, Loc, T));
1038 DeclarationName TypeDN = S.PP.getIdentifierInfo("type");
1039 LookupResult R(S, TypeDN, Loc, Sema::LookupOrdinaryName);
1040 if (lookupStdTypeTraitMember(
1041 S, R, Loc, "tuple_element", Args,
1042 diag::err_decomp_decl_std_tuple_element_not_specialized))
1045 auto *TD = R.getAsSingle<TypeDecl>();
1047 R.suppressDiagnostics();
1048 S.Diag(Loc, diag::err_decomp_decl_std_tuple_element_not_specialized)
1049 << printTemplateArgs(S.Context.getPrintingPolicy(), Args);
1051 S.Diag(R.getRepresentativeDecl()->getLocation(), diag::note_declared_at);
1055 return S.Context.getTypeDeclType(TD);
1059 struct BindingDiagnosticTrap {
1061 DiagnosticErrorTrap Trap;
1064 BindingDiagnosticTrap(Sema &S, BindingDecl *BD)
1065 : S(S), Trap(S.Diags), BD(BD) {}
1066 ~BindingDiagnosticTrap() {
1067 if (Trap.hasErrorOccurred())
1068 S.Diag(BD->getLocation(), diag::note_in_binding_decl_init) << BD;
1073 static bool checkTupleLikeDecomposition(Sema &S,
1074 ArrayRef<BindingDecl *> Bindings,
1075 VarDecl *Src, QualType DecompType,
1076 const llvm::APSInt &TupleSize) {
1077 if ((int64_t)Bindings.size() != TupleSize) {
1078 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
1079 << DecompType << (unsigned)Bindings.size() << TupleSize.toString(10)
1080 << (TupleSize < Bindings.size());
1084 if (Bindings.empty())
1087 DeclarationName GetDN = S.PP.getIdentifierInfo("get");
1090 // The unqualified-id get is looked up in the scope of E by class member
1092 LookupResult MemberGet(S, GetDN, Src->getLocation(), Sema::LookupMemberName);
1093 bool UseMemberGet = false;
1094 if (S.isCompleteType(Src->getLocation(), DecompType)) {
1095 if (auto *RD = DecompType->getAsCXXRecordDecl())
1096 S.LookupQualifiedName(MemberGet, RD);
1097 if (MemberGet.isAmbiguous())
1099 UseMemberGet = !MemberGet.empty();
1100 S.FilterAcceptableTemplateNames(MemberGet);
1104 for (auto *B : Bindings) {
1105 BindingDiagnosticTrap Trap(S, B);
1106 SourceLocation Loc = B->getLocation();
1108 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
1112 // e is an lvalue if the type of the entity is an lvalue reference and
1113 // an xvalue otherwise
1114 if (!Src->getType()->isLValueReferenceType())
1115 E = ImplicitCastExpr::Create(S.Context, E.get()->getType(), CK_NoOp,
1116 E.get(), nullptr, VK_XValue);
1118 TemplateArgumentListInfo Args(Loc, Loc);
1120 getTrivialIntegralTemplateArgument(S, Loc, S.Context.getSizeType(), I));
1123 // if [lookup of member get] finds at least one declaration, the
1124 // initializer is e.get<i-1>().
1125 E = S.BuildMemberReferenceExpr(E.get(), DecompType, Loc, false,
1126 CXXScopeSpec(), SourceLocation(), nullptr,
1127 MemberGet, &Args, nullptr);
1131 E = S.ActOnCallExpr(nullptr, E.get(), Loc, None, Loc);
1133 // Otherwise, the initializer is get<i-1>(e), where get is looked up
1134 // in the associated namespaces.
1135 Expr *Get = UnresolvedLookupExpr::Create(
1136 S.Context, nullptr, NestedNameSpecifierLoc(), SourceLocation(),
1137 DeclarationNameInfo(GetDN, Loc), /*RequiresADL*/true, &Args,
1138 UnresolvedSetIterator(), UnresolvedSetIterator());
1140 Expr *Arg = E.get();
1141 E = S.ActOnCallExpr(nullptr, Get, Loc, Arg, Loc);
1145 Expr *Init = E.get();
1147 // Given the type T designated by std::tuple_element<i - 1, E>::type,
1148 QualType T = getTupleLikeElementType(S, Loc, I, DecompType);
1152 // each vi is a variable of type "reference to T" initialized with the
1153 // initializer, where the reference is an lvalue reference if the
1154 // initializer is an lvalue and an rvalue reference otherwise
1156 S.BuildReferenceType(T, E.get()->isLValue(), Loc, B->getDeclName());
1157 if (RefType.isNull())
1159 auto *RefVD = VarDecl::Create(
1160 S.Context, Src->getDeclContext(), Loc, Loc,
1161 B->getDeclName().getAsIdentifierInfo(), RefType,
1162 S.Context.getTrivialTypeSourceInfo(T, Loc), Src->getStorageClass());
1163 RefVD->setLexicalDeclContext(Src->getLexicalDeclContext());
1164 RefVD->setTSCSpec(Src->getTSCSpec());
1165 RefVD->setImplicit();
1166 if (Src->isInlineSpecified())
1167 RefVD->setInlineSpecified();
1168 RefVD->getLexicalDeclContext()->addHiddenDecl(RefVD);
1170 InitializedEntity Entity = InitializedEntity::InitializeBinding(RefVD);
1171 InitializationKind Kind = InitializationKind::CreateCopy(Loc, Loc);
1172 InitializationSequence Seq(S, Entity, Kind, Init);
1173 E = Seq.Perform(S, Entity, Kind, Init);
1176 E = S.ActOnFinishFullExpr(E.get(), Loc);
1179 RefVD->setInit(E.get());
1180 RefVD->checkInitIsICE();
1182 E = S.BuildDeclarationNameExpr(CXXScopeSpec(),
1183 DeclarationNameInfo(B->getDeclName(), Loc),
1188 B->setBinding(T, E.get());
1195 /// Find the base class to decompose in a built-in decomposition of a class type.
1196 /// This base class search is, unfortunately, not quite like any other that we
1197 /// perform anywhere else in C++.
1198 static const CXXRecordDecl *findDecomposableBaseClass(Sema &S,
1200 const CXXRecordDecl *RD,
1201 CXXCastPath &BasePath) {
1202 auto BaseHasFields = [](const CXXBaseSpecifier *Specifier,
1203 CXXBasePath &Path) {
1204 return Specifier->getType()->getAsCXXRecordDecl()->hasDirectFields();
1207 const CXXRecordDecl *ClassWithFields = nullptr;
1208 if (RD->hasDirectFields())
1210 // Otherwise, all of E's non-static data members shall be public direct
1212 ClassWithFields = RD;
1216 Paths.setOrigin(const_cast<CXXRecordDecl*>(RD));
1217 if (!RD->lookupInBases(BaseHasFields, Paths)) {
1218 // If no classes have fields, just decompose RD itself. (This will work
1219 // if and only if zero bindings were provided.)
1223 CXXBasePath *BestPath = nullptr;
1224 for (auto &P : Paths) {
1227 else if (!S.Context.hasSameType(P.back().Base->getType(),
1228 BestPath->back().Base->getType())) {
1230 S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
1231 << false << RD << BestPath->back().Base->getType()
1232 << P.back().Base->getType();
1234 } else if (P.Access < BestPath->Access) {
1239 // ... unambiguous ...
1240 QualType BaseType = BestPath->back().Base->getType();
1241 if (Paths.isAmbiguous(S.Context.getCanonicalType(BaseType))) {
1242 S.Diag(Loc, diag::err_decomp_decl_ambiguous_base)
1243 << RD << BaseType << S.getAmbiguousPathsDisplayString(Paths);
1247 // ... public base class of E.
1248 if (BestPath->Access != AS_public) {
1249 S.Diag(Loc, diag::err_decomp_decl_non_public_base)
1251 for (auto &BS : *BestPath) {
1252 if (BS.Base->getAccessSpecifier() != AS_public) {
1253 S.Diag(BS.Base->getLocStart(), diag::note_access_constrained_by_path)
1254 << (BS.Base->getAccessSpecifier() == AS_protected)
1255 << (BS.Base->getAccessSpecifierAsWritten() == AS_none);
1262 ClassWithFields = BaseType->getAsCXXRecordDecl();
1263 S.BuildBasePathArray(Paths, BasePath);
1266 // The above search did not check whether the selected class itself has base
1267 // classes with fields, so check that now.
1269 if (ClassWithFields->lookupInBases(BaseHasFields, Paths)) {
1270 S.Diag(Loc, diag::err_decomp_decl_multiple_bases_with_members)
1271 << (ClassWithFields == RD) << RD << ClassWithFields
1272 << Paths.front().back().Base->getType();
1276 return ClassWithFields;
1279 static bool checkMemberDecomposition(Sema &S, ArrayRef<BindingDecl*> Bindings,
1280 ValueDecl *Src, QualType DecompType,
1281 const CXXRecordDecl *RD) {
1282 CXXCastPath BasePath;
1283 RD = findDecomposableBaseClass(S, Src->getLocation(), RD, BasePath);
1286 QualType BaseType = S.Context.getQualifiedType(S.Context.getRecordType(RD),
1287 DecompType.getQualifiers());
1289 auto DiagnoseBadNumberOfBindings = [&]() -> bool {
1290 unsigned NumFields =
1291 std::count_if(RD->field_begin(), RD->field_end(),
1292 [](FieldDecl *FD) { return !FD->isUnnamedBitfield(); });
1293 assert(Bindings.size() != NumFields);
1294 S.Diag(Src->getLocation(), diag::err_decomp_decl_wrong_number_bindings)
1295 << DecompType << (unsigned)Bindings.size() << NumFields
1296 << (NumFields < Bindings.size());
1300 // all of E's non-static data members shall be public [...] members,
1301 // E shall not have an anonymous union member, ...
1303 for (auto *FD : RD->fields()) {
1304 if (FD->isUnnamedBitfield())
1307 if (FD->isAnonymousStructOrUnion()) {
1308 S.Diag(Src->getLocation(), diag::err_decomp_decl_anon_union_member)
1309 << DecompType << FD->getType()->isUnionType();
1310 S.Diag(FD->getLocation(), diag::note_declared_at);
1314 // We have a real field to bind.
1315 if (I >= Bindings.size())
1316 return DiagnoseBadNumberOfBindings();
1317 auto *B = Bindings[I++];
1319 SourceLocation Loc = B->getLocation();
1320 if (FD->getAccess() != AS_public) {
1321 S.Diag(Loc, diag::err_decomp_decl_non_public_member) << FD << DecompType;
1323 // Determine whether the access specifier was explicit.
1324 bool Implicit = true;
1325 for (const auto *D : RD->decls()) {
1326 if (declaresSameEntity(D, FD))
1328 if (isa<AccessSpecDecl>(D)) {
1334 S.Diag(FD->getLocation(), diag::note_access_natural)
1335 << (FD->getAccess() == AS_protected) << Implicit;
1339 // Initialize the binding to Src.FD.
1340 ExprResult E = S.BuildDeclRefExpr(Src, DecompType, VK_LValue, Loc);
1343 E = S.ImpCastExprToType(E.get(), BaseType, CK_UncheckedDerivedToBase,
1344 VK_LValue, &BasePath);
1347 E = S.BuildFieldReferenceExpr(E.get(), /*IsArrow*/ false, Loc,
1349 DeclAccessPair::make(FD, FD->getAccess()),
1350 DeclarationNameInfo(FD->getDeclName(), Loc));
1354 // If the type of the member is T, the referenced type is cv T, where cv is
1355 // the cv-qualification of the decomposition expression.
1357 // FIXME: We resolve a defect here: if the field is mutable, we do not add
1358 // 'const' to the type of the field.
1359 Qualifiers Q = DecompType.getQualifiers();
1360 if (FD->isMutable())
1362 B->setBinding(S.BuildQualifiedType(FD->getType(), Loc, Q), E.get());
1365 if (I != Bindings.size())
1366 return DiagnoseBadNumberOfBindings();
1371 void Sema::CheckCompleteDecompositionDeclaration(DecompositionDecl *DD) {
1372 QualType DecompType = DD->getType();
1374 // If the type of the decomposition is dependent, then so is the type of
1376 if (DecompType->isDependentType()) {
1377 for (auto *B : DD->bindings())
1378 B->setType(Context.DependentTy);
1382 DecompType = DecompType.getNonReferenceType();
1383 ArrayRef<BindingDecl*> Bindings = DD->bindings();
1385 // C++1z [dcl.decomp]/2:
1386 // If E is an array type [...]
1387 // As an extension, we also support decomposition of built-in complex and
1389 if (auto *CAT = Context.getAsConstantArrayType(DecompType)) {
1390 if (checkArrayDecomposition(*this, Bindings, DD, DecompType, CAT))
1391 DD->setInvalidDecl();
1394 if (auto *VT = DecompType->getAs<VectorType>()) {
1395 if (checkVectorDecomposition(*this, Bindings, DD, DecompType, VT))
1396 DD->setInvalidDecl();
1399 if (auto *CT = DecompType->getAs<ComplexType>()) {
1400 if (checkComplexDecomposition(*this, Bindings, DD, DecompType, CT))
1401 DD->setInvalidDecl();
1405 // C++1z [dcl.decomp]/3:
1406 // if the expression std::tuple_size<E>::value is a well-formed integral
1407 // constant expression, [...]
1408 llvm::APSInt TupleSize(32);
1409 switch (isTupleLike(*this, DD->getLocation(), DecompType, TupleSize)) {
1410 case IsTupleLike::Error:
1411 DD->setInvalidDecl();
1414 case IsTupleLike::TupleLike:
1415 if (checkTupleLikeDecomposition(*this, Bindings, DD, DecompType, TupleSize))
1416 DD->setInvalidDecl();
1419 case IsTupleLike::NotTupleLike:
1423 // C++1z [dcl.dcl]/8:
1424 // [E shall be of array or non-union class type]
1425 CXXRecordDecl *RD = DecompType->getAsCXXRecordDecl();
1426 if (!RD || RD->isUnion()) {
1427 Diag(DD->getLocation(), diag::err_decomp_decl_unbindable_type)
1428 << DD << !RD << DecompType;
1429 DD->setInvalidDecl();
1433 // C++1z [dcl.decomp]/4:
1434 // all of E's non-static data members shall be [...] direct members of
1435 // E or of the same unambiguous public base class of E, ...
1436 if (checkMemberDecomposition(*this, Bindings, DD, DecompType, RD))
1437 DD->setInvalidDecl();
1440 /// \brief Merge the exception specifications of two variable declarations.
1442 /// This is called when there's a redeclaration of a VarDecl. The function
1443 /// checks if the redeclaration might have an exception specification and
1444 /// validates compatibility and merges the specs if necessary.
1445 void Sema::MergeVarDeclExceptionSpecs(VarDecl *New, VarDecl *Old) {
1446 // Shortcut if exceptions are disabled.
1447 if (!getLangOpts().CXXExceptions)
1450 assert(Context.hasSameType(New->getType(), Old->getType()) &&
1451 "Should only be called if types are otherwise the same.");
1453 QualType NewType = New->getType();
1454 QualType OldType = Old->getType();
1456 // We're only interested in pointers and references to functions, as well
1457 // as pointers to member functions.
1458 if (const ReferenceType *R = NewType->getAs<ReferenceType>()) {
1459 NewType = R->getPointeeType();
1460 OldType = OldType->getAs<ReferenceType>()->getPointeeType();
1461 } else if (const PointerType *P = NewType->getAs<PointerType>()) {
1462 NewType = P->getPointeeType();
1463 OldType = OldType->getAs<PointerType>()->getPointeeType();
1464 } else if (const MemberPointerType *M = NewType->getAs<MemberPointerType>()) {
1465 NewType = M->getPointeeType();
1466 OldType = OldType->getAs<MemberPointerType>()->getPointeeType();
1469 if (!NewType->isFunctionProtoType())
1472 // There's lots of special cases for functions. For function pointers, system
1473 // libraries are hopefully not as broken so that we don't need these
1475 if (CheckEquivalentExceptionSpec(
1476 OldType->getAs<FunctionProtoType>(), Old->getLocation(),
1477 NewType->getAs<FunctionProtoType>(), New->getLocation())) {
1478 New->setInvalidDecl();
1482 /// CheckCXXDefaultArguments - Verify that the default arguments for a
1483 /// function declaration are well-formed according to C++
1484 /// [dcl.fct.default].
1485 void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) {
1486 unsigned NumParams = FD->getNumParams();
1489 // Find first parameter with a default argument
1490 for (p = 0; p < NumParams; ++p) {
1491 ParmVarDecl *Param = FD->getParamDecl(p);
1492 if (Param->hasDefaultArg())
1496 // C++11 [dcl.fct.default]p4:
1497 // In a given function declaration, each parameter subsequent to a parameter
1498 // with a default argument shall have a default argument supplied in this or
1499 // a previous declaration or shall be a function parameter pack. A default
1500 // argument shall not be redefined by a later declaration (not even to the
1502 unsigned LastMissingDefaultArg = 0;
1503 for (; p < NumParams; ++p) {
1504 ParmVarDecl *Param = FD->getParamDecl(p);
1505 if (!Param->hasDefaultArg() && !Param->isParameterPack()) {
1506 if (Param->isInvalidDecl())
1507 /* We already complained about this parameter. */;
1508 else if (Param->getIdentifier())
1509 Diag(Param->getLocation(),
1510 diag::err_param_default_argument_missing_name)
1511 << Param->getIdentifier();
1513 Diag(Param->getLocation(),
1514 diag::err_param_default_argument_missing);
1516 LastMissingDefaultArg = p;
1520 if (LastMissingDefaultArg > 0) {
1521 // Some default arguments were missing. Clear out all of the
1522 // default arguments up to (and including) the last missing
1523 // default argument, so that we leave the function parameters
1524 // in a semantically valid state.
1525 for (p = 0; p <= LastMissingDefaultArg; ++p) {
1526 ParmVarDecl *Param = FD->getParamDecl(p);
1527 if (Param->hasDefaultArg()) {
1528 Param->setDefaultArg(nullptr);
1534 // CheckConstexprParameterTypes - Check whether a function's parameter types
1535 // are all literal types. If so, return true. If not, produce a suitable
1536 // diagnostic and return false.
1537 static bool CheckConstexprParameterTypes(Sema &SemaRef,
1538 const FunctionDecl *FD) {
1539 unsigned ArgIndex = 0;
1540 const FunctionProtoType *FT = FD->getType()->getAs<FunctionProtoType>();
1541 for (FunctionProtoType::param_type_iterator i = FT->param_type_begin(),
1542 e = FT->param_type_end();
1543 i != e; ++i, ++ArgIndex) {
1544 const ParmVarDecl *PD = FD->getParamDecl(ArgIndex);
1545 SourceLocation ParamLoc = PD->getLocation();
1546 if (!(*i)->isDependentType() &&
1547 SemaRef.RequireLiteralType(ParamLoc, *i,
1548 diag::err_constexpr_non_literal_param,
1549 ArgIndex+1, PD->getSourceRange(),
1550 isa<CXXConstructorDecl>(FD)))
1556 /// \brief Get diagnostic %select index for tag kind for
1557 /// record diagnostic message.
1558 /// WARNING: Indexes apply to particular diagnostics only!
1560 /// \returns diagnostic %select index.
1561 static unsigned getRecordDiagFromTagKind(TagTypeKind Tag) {
1563 case TTK_Struct: return 0;
1564 case TTK_Interface: return 1;
1565 case TTK_Class: return 2;
1566 default: llvm_unreachable("Invalid tag kind for record diagnostic!");
1570 // CheckConstexprFunctionDecl - Check whether a function declaration satisfies
1571 // the requirements of a constexpr function definition or a constexpr
1572 // constructor definition. If so, return true. If not, produce appropriate
1573 // diagnostics and return false.
1575 // This implements C++11 [dcl.constexpr]p3,4, as amended by DR1360.
1576 bool Sema::CheckConstexprFunctionDecl(const FunctionDecl *NewFD) {
1577 const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(NewFD);
1578 if (MD && MD->isInstance()) {
1579 // C++11 [dcl.constexpr]p4:
1580 // The definition of a constexpr constructor shall satisfy the following
1582 // - the class shall not have any virtual base classes;
1583 const CXXRecordDecl *RD = MD->getParent();
1584 if (RD->getNumVBases()) {
1585 Diag(NewFD->getLocation(), diag::err_constexpr_virtual_base)
1586 << isa<CXXConstructorDecl>(NewFD)
1587 << getRecordDiagFromTagKind(RD->getTagKind()) << RD->getNumVBases();
1588 for (const auto &I : RD->vbases())
1589 Diag(I.getLocStart(),
1590 diag::note_constexpr_virtual_base_here) << I.getSourceRange();
1595 if (!isa<CXXConstructorDecl>(NewFD)) {
1596 // C++11 [dcl.constexpr]p3:
1597 // The definition of a constexpr function shall satisfy the following
1599 // - it shall not be virtual;
1600 const CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(NewFD);
1601 if (Method && Method->isVirtual()) {
1602 Method = Method->getCanonicalDecl();
1603 Diag(Method->getLocation(), diag::err_constexpr_virtual);
1605 // If it's not obvious why this function is virtual, find an overridden
1606 // function which uses the 'virtual' keyword.
1607 const CXXMethodDecl *WrittenVirtual = Method;
1608 while (!WrittenVirtual->isVirtualAsWritten())
1609 WrittenVirtual = *WrittenVirtual->begin_overridden_methods();
1610 if (WrittenVirtual != Method)
1611 Diag(WrittenVirtual->getLocation(),
1612 diag::note_overridden_virtual_function);
1616 // - its return type shall be a literal type;
1617 QualType RT = NewFD->getReturnType();
1618 if (!RT->isDependentType() &&
1619 RequireLiteralType(NewFD->getLocation(), RT,
1620 diag::err_constexpr_non_literal_return))
1624 // - each of its parameter types shall be a literal type;
1625 if (!CheckConstexprParameterTypes(*this, NewFD))
1631 /// Check the given declaration statement is legal within a constexpr function
1632 /// body. C++11 [dcl.constexpr]p3,p4, and C++1y [dcl.constexpr]p3.
1634 /// \return true if the body is OK (maybe only as an extension), false if we
1635 /// have diagnosed a problem.
1636 static bool CheckConstexprDeclStmt(Sema &SemaRef, const FunctionDecl *Dcl,
1637 DeclStmt *DS, SourceLocation &Cxx1yLoc) {
1638 // C++11 [dcl.constexpr]p3 and p4:
1639 // The definition of a constexpr function(p3) or constructor(p4) [...] shall
1641 for (const auto *DclIt : DS->decls()) {
1642 switch (DclIt->getKind()) {
1643 case Decl::StaticAssert:
1645 case Decl::UsingShadow:
1646 case Decl::UsingDirective:
1647 case Decl::UnresolvedUsingTypename:
1648 case Decl::UnresolvedUsingValue:
1649 // - static_assert-declarations
1650 // - using-declarations,
1651 // - using-directives,
1655 case Decl::TypeAlias: {
1656 // - typedef declarations and alias-declarations that do not define
1657 // classes or enumerations,
1658 const auto *TN = cast<TypedefNameDecl>(DclIt);
1659 if (TN->getUnderlyingType()->isVariablyModifiedType()) {
1660 // Don't allow variably-modified types in constexpr functions.
1661 TypeLoc TL = TN->getTypeSourceInfo()->getTypeLoc();
1662 SemaRef.Diag(TL.getBeginLoc(), diag::err_constexpr_vla)
1663 << TL.getSourceRange() << TL.getType()
1664 << isa<CXXConstructorDecl>(Dcl);
1671 case Decl::CXXRecord:
1672 // C++1y allows types to be defined, not just declared.
1673 if (cast<TagDecl>(DclIt)->isThisDeclarationADefinition())
1674 SemaRef.Diag(DS->getLocStart(),
1675 SemaRef.getLangOpts().CPlusPlus14
1676 ? diag::warn_cxx11_compat_constexpr_type_definition
1677 : diag::ext_constexpr_type_definition)
1678 << isa<CXXConstructorDecl>(Dcl);
1681 case Decl::EnumConstant:
1682 case Decl::IndirectField:
1684 // These can only appear with other declarations which are banned in
1685 // C++11 and permitted in C++1y, so ignore them.
1689 case Decl::Decomposition: {
1690 // C++1y [dcl.constexpr]p3 allows anything except:
1691 // a definition of a variable of non-literal type or of static or
1692 // thread storage duration or for which no initialization is performed.
1693 const auto *VD = cast<VarDecl>(DclIt);
1694 if (VD->isThisDeclarationADefinition()) {
1695 if (VD->isStaticLocal()) {
1696 SemaRef.Diag(VD->getLocation(),
1697 diag::err_constexpr_local_var_static)
1698 << isa<CXXConstructorDecl>(Dcl)
1699 << (VD->getTLSKind() == VarDecl::TLS_Dynamic);
1702 if (!VD->getType()->isDependentType() &&
1703 SemaRef.RequireLiteralType(
1704 VD->getLocation(), VD->getType(),
1705 diag::err_constexpr_local_var_non_literal_type,
1706 isa<CXXConstructorDecl>(Dcl)))
1708 if (!VD->getType()->isDependentType() &&
1709 !VD->hasInit() && !VD->isCXXForRangeDecl()) {
1710 SemaRef.Diag(VD->getLocation(),
1711 diag::err_constexpr_local_var_no_init)
1712 << isa<CXXConstructorDecl>(Dcl);
1716 SemaRef.Diag(VD->getLocation(),
1717 SemaRef.getLangOpts().CPlusPlus14
1718 ? diag::warn_cxx11_compat_constexpr_local_var
1719 : diag::ext_constexpr_local_var)
1720 << isa<CXXConstructorDecl>(Dcl);
1724 case Decl::NamespaceAlias:
1725 case Decl::Function:
1726 // These are disallowed in C++11 and permitted in C++1y. Allow them
1727 // everywhere as an extension.
1728 if (!Cxx1yLoc.isValid())
1729 Cxx1yLoc = DS->getLocStart();
1733 SemaRef.Diag(DS->getLocStart(), diag::err_constexpr_body_invalid_stmt)
1734 << isa<CXXConstructorDecl>(Dcl);
1742 /// Check that the given field is initialized within a constexpr constructor.
1744 /// \param Dcl The constexpr constructor being checked.
1745 /// \param Field The field being checked. This may be a member of an anonymous
1746 /// struct or union nested within the class being checked.
1747 /// \param Inits All declarations, including anonymous struct/union members and
1748 /// indirect members, for which any initialization was provided.
1749 /// \param Diagnosed Set to true if an error is produced.
1750 static void CheckConstexprCtorInitializer(Sema &SemaRef,
1751 const FunctionDecl *Dcl,
1753 llvm::SmallSet<Decl*, 16> &Inits,
1755 if (Field->isInvalidDecl())
1758 if (Field->isUnnamedBitfield())
1761 // Anonymous unions with no variant members and empty anonymous structs do not
1762 // need to be explicitly initialized. FIXME: Anonymous structs that contain no
1763 // indirect fields don't need initializing.
1764 if (Field->isAnonymousStructOrUnion() &&
1765 (Field->getType()->isUnionType()
1766 ? !Field->getType()->getAsCXXRecordDecl()->hasVariantMembers()
1767 : Field->getType()->getAsCXXRecordDecl()->isEmpty()))
1770 if (!Inits.count(Field)) {
1772 SemaRef.Diag(Dcl->getLocation(), diag::err_constexpr_ctor_missing_init);
1775 SemaRef.Diag(Field->getLocation(), diag::note_constexpr_ctor_missing_init);
1776 } else if (Field->isAnonymousStructOrUnion()) {
1777 const RecordDecl *RD = Field->getType()->castAs<RecordType>()->getDecl();
1778 for (auto *I : RD->fields())
1779 // If an anonymous union contains an anonymous struct of which any member
1780 // is initialized, all members must be initialized.
1781 if (!RD->isUnion() || Inits.count(I))
1782 CheckConstexprCtorInitializer(SemaRef, Dcl, I, Inits, Diagnosed);
1786 /// Check the provided statement is allowed in a constexpr function
1789 CheckConstexprFunctionStmt(Sema &SemaRef, const FunctionDecl *Dcl, Stmt *S,
1790 SmallVectorImpl<SourceLocation> &ReturnStmts,
1791 SourceLocation &Cxx1yLoc) {
1792 // - its function-body shall be [...] a compound-statement that contains only
1793 switch (S->getStmtClass()) {
1794 case Stmt::NullStmtClass:
1795 // - null statements,
1798 case Stmt::DeclStmtClass:
1799 // - static_assert-declarations
1800 // - using-declarations,
1801 // - using-directives,
1802 // - typedef declarations and alias-declarations that do not define
1803 // classes or enumerations,
1804 if (!CheckConstexprDeclStmt(SemaRef, Dcl, cast<DeclStmt>(S), Cxx1yLoc))
1808 case Stmt::ReturnStmtClass:
1809 // - and exactly one return statement;
1810 if (isa<CXXConstructorDecl>(Dcl)) {
1811 // C++1y allows return statements in constexpr constructors.
1812 if (!Cxx1yLoc.isValid())
1813 Cxx1yLoc = S->getLocStart();
1817 ReturnStmts.push_back(S->getLocStart());
1820 case Stmt::CompoundStmtClass: {
1821 // C++1y allows compound-statements.
1822 if (!Cxx1yLoc.isValid())
1823 Cxx1yLoc = S->getLocStart();
1825 CompoundStmt *CompStmt = cast<CompoundStmt>(S);
1826 for (auto *BodyIt : CompStmt->body()) {
1827 if (!CheckConstexprFunctionStmt(SemaRef, Dcl, BodyIt, ReturnStmts,
1834 case Stmt::AttributedStmtClass:
1835 if (!Cxx1yLoc.isValid())
1836 Cxx1yLoc = S->getLocStart();
1839 case Stmt::IfStmtClass: {
1840 // C++1y allows if-statements.
1841 if (!Cxx1yLoc.isValid())
1842 Cxx1yLoc = S->getLocStart();
1844 IfStmt *If = cast<IfStmt>(S);
1845 if (!CheckConstexprFunctionStmt(SemaRef, Dcl, If->getThen(), ReturnStmts,
1848 if (If->getElse() &&
1849 !CheckConstexprFunctionStmt(SemaRef, Dcl, If->getElse(), ReturnStmts,
1855 case Stmt::WhileStmtClass:
1856 case Stmt::DoStmtClass:
1857 case Stmt::ForStmtClass:
1858 case Stmt::CXXForRangeStmtClass:
1859 case Stmt::ContinueStmtClass:
1860 // C++1y allows all of these. We don't allow them as extensions in C++11,
1861 // because they don't make sense without variable mutation.
1862 if (!SemaRef.getLangOpts().CPlusPlus14)
1864 if (!Cxx1yLoc.isValid())
1865 Cxx1yLoc = S->getLocStart();
1866 for (Stmt *SubStmt : S->children())
1868 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
1873 case Stmt::SwitchStmtClass:
1874 case Stmt::CaseStmtClass:
1875 case Stmt::DefaultStmtClass:
1876 case Stmt::BreakStmtClass:
1877 // C++1y allows switch-statements, and since they don't need variable
1878 // mutation, we can reasonably allow them in C++11 as an extension.
1879 if (!Cxx1yLoc.isValid())
1880 Cxx1yLoc = S->getLocStart();
1881 for (Stmt *SubStmt : S->children())
1883 !CheckConstexprFunctionStmt(SemaRef, Dcl, SubStmt, ReturnStmts,
1892 // C++1y allows expression-statements.
1893 if (!Cxx1yLoc.isValid())
1894 Cxx1yLoc = S->getLocStart();
1898 SemaRef.Diag(S->getLocStart(), diag::err_constexpr_body_invalid_stmt)
1899 << isa<CXXConstructorDecl>(Dcl);
1903 /// Check the body for the given constexpr function declaration only contains
1904 /// the permitted types of statement. C++11 [dcl.constexpr]p3,p4.
1906 /// \return true if the body is OK, false if we have diagnosed a problem.
1907 bool Sema::CheckConstexprFunctionBody(const FunctionDecl *Dcl, Stmt *Body) {
1908 if (isa<CXXTryStmt>(Body)) {
1909 // C++11 [dcl.constexpr]p3:
1910 // The definition of a constexpr function shall satisfy the following
1911 // constraints: [...]
1912 // - its function-body shall be = delete, = default, or a
1913 // compound-statement
1915 // C++11 [dcl.constexpr]p4:
1916 // In the definition of a constexpr constructor, [...]
1917 // - its function-body shall not be a function-try-block;
1918 Diag(Body->getLocStart(), diag::err_constexpr_function_try_block)
1919 << isa<CXXConstructorDecl>(Dcl);
1923 SmallVector<SourceLocation, 4> ReturnStmts;
1925 // - its function-body shall be [...] a compound-statement that contains only
1926 // [... list of cases ...]
1927 CompoundStmt *CompBody = cast<CompoundStmt>(Body);
1928 SourceLocation Cxx1yLoc;
1929 for (auto *BodyIt : CompBody->body()) {
1930 if (!CheckConstexprFunctionStmt(*this, Dcl, BodyIt, ReturnStmts, Cxx1yLoc))
1934 if (Cxx1yLoc.isValid())
1936 getLangOpts().CPlusPlus14
1937 ? diag::warn_cxx11_compat_constexpr_body_invalid_stmt
1938 : diag::ext_constexpr_body_invalid_stmt)
1939 << isa<CXXConstructorDecl>(Dcl);
1941 if (const CXXConstructorDecl *Constructor
1942 = dyn_cast<CXXConstructorDecl>(Dcl)) {
1943 const CXXRecordDecl *RD = Constructor->getParent();
1945 // - every non-variant non-static data member and base class sub-object
1946 // shall be initialized;
1948 // - if the class is a union having variant members, exactly one of them
1949 // shall be initialized;
1950 if (RD->isUnion()) {
1951 if (Constructor->getNumCtorInitializers() == 0 &&
1952 RD->hasVariantMembers()) {
1953 Diag(Dcl->getLocation(), diag::err_constexpr_union_ctor_no_init);
1956 } else if (!Constructor->isDependentContext() &&
1957 !Constructor->isDelegatingConstructor()) {
1958 assert(RD->getNumVBases() == 0 && "constexpr ctor with virtual bases");
1960 // Skip detailed checking if we have enough initializers, and we would
1961 // allow at most one initializer per member.
1962 bool AnyAnonStructUnionMembers = false;
1963 unsigned Fields = 0;
1964 for (CXXRecordDecl::field_iterator I = RD->field_begin(),
1965 E = RD->field_end(); I != E; ++I, ++Fields) {
1966 if (I->isAnonymousStructOrUnion()) {
1967 AnyAnonStructUnionMembers = true;
1972 // - if the class is a union-like class, but is not a union, for each of
1973 // its anonymous union members having variant members, exactly one of
1974 // them shall be initialized;
1975 if (AnyAnonStructUnionMembers ||
1976 Constructor->getNumCtorInitializers() != RD->getNumBases() + Fields) {
1977 // Check initialization of non-static data members. Base classes are
1978 // always initialized so do not need to be checked. Dependent bases
1979 // might not have initializers in the member initializer list.
1980 llvm::SmallSet<Decl*, 16> Inits;
1981 for (const auto *I: Constructor->inits()) {
1982 if (FieldDecl *FD = I->getMember())
1984 else if (IndirectFieldDecl *ID = I->getIndirectMember())
1985 Inits.insert(ID->chain_begin(), ID->chain_end());
1988 bool Diagnosed = false;
1989 for (auto *I : RD->fields())
1990 CheckConstexprCtorInitializer(*this, Dcl, I, Inits, Diagnosed);
1996 if (ReturnStmts.empty()) {
1997 // C++1y doesn't require constexpr functions to contain a 'return'
1998 // statement. We still do, unless the return type might be void, because
1999 // otherwise if there's no return statement, the function cannot
2000 // be used in a core constant expression.
2001 bool OK = getLangOpts().CPlusPlus14 &&
2002 (Dcl->getReturnType()->isVoidType() ||
2003 Dcl->getReturnType()->isDependentType());
2004 Diag(Dcl->getLocation(),
2005 OK ? diag::warn_cxx11_compat_constexpr_body_no_return
2006 : diag::err_constexpr_body_no_return);
2009 } else if (ReturnStmts.size() > 1) {
2010 Diag(ReturnStmts.back(),
2011 getLangOpts().CPlusPlus14
2012 ? diag::warn_cxx11_compat_constexpr_body_multiple_return
2013 : diag::ext_constexpr_body_multiple_return);
2014 for (unsigned I = 0; I < ReturnStmts.size() - 1; ++I)
2015 Diag(ReturnStmts[I], diag::note_constexpr_body_previous_return);
2019 // C++11 [dcl.constexpr]p5:
2020 // if no function argument values exist such that the function invocation
2021 // substitution would produce a constant expression, the program is
2022 // ill-formed; no diagnostic required.
2023 // C++11 [dcl.constexpr]p3:
2024 // - every constructor call and implicit conversion used in initializing the
2025 // return value shall be one of those allowed in a constant expression.
2026 // C++11 [dcl.constexpr]p4:
2027 // - every constructor involved in initializing non-static data members and
2028 // base class sub-objects shall be a constexpr constructor.
2029 SmallVector<PartialDiagnosticAt, 8> Diags;
2030 if (!Expr::isPotentialConstantExpr(Dcl, Diags)) {
2031 Diag(Dcl->getLocation(), diag::ext_constexpr_function_never_constant_expr)
2032 << isa<CXXConstructorDecl>(Dcl);
2033 for (size_t I = 0, N = Diags.size(); I != N; ++I)
2034 Diag(Diags[I].first, Diags[I].second);
2035 // Don't return false here: we allow this for compatibility in
2042 /// isCurrentClassName - Determine whether the identifier II is the
2043 /// name of the class type currently being defined. In the case of
2044 /// nested classes, this will only return true if II is the name of
2045 /// the innermost class.
2046 bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *,
2047 const CXXScopeSpec *SS) {
2048 assert(getLangOpts().CPlusPlus && "No class names in C!");
2050 CXXRecordDecl *CurDecl;
2051 if (SS && SS->isSet() && !SS->isInvalid()) {
2052 DeclContext *DC = computeDeclContext(*SS, true);
2053 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
2055 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
2057 if (CurDecl && CurDecl->getIdentifier())
2058 return &II == CurDecl->getIdentifier();
2062 /// \brief Determine whether the identifier II is a typo for the name of
2063 /// the class type currently being defined. If so, update it to the identifier
2064 /// that should have been used.
2065 bool Sema::isCurrentClassNameTypo(IdentifierInfo *&II, const CXXScopeSpec *SS) {
2066 assert(getLangOpts().CPlusPlus && "No class names in C!");
2068 if (!getLangOpts().SpellChecking)
2071 CXXRecordDecl *CurDecl;
2072 if (SS && SS->isSet() && !SS->isInvalid()) {
2073 DeclContext *DC = computeDeclContext(*SS, true);
2074 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC);
2076 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext);
2078 if (CurDecl && CurDecl->getIdentifier() && II != CurDecl->getIdentifier() &&
2079 3 * II->getName().edit_distance(CurDecl->getIdentifier()->getName())
2080 < II->getLength()) {
2081 II = CurDecl->getIdentifier();
2088 /// \brief Determine whether the given class is a base class of the given
2089 /// class, including looking at dependent bases.
2090 static bool findCircularInheritance(const CXXRecordDecl *Class,
2091 const CXXRecordDecl *Current) {
2092 SmallVector<const CXXRecordDecl*, 8> Queue;
2094 Class = Class->getCanonicalDecl();
2096 for (const auto &I : Current->bases()) {
2097 CXXRecordDecl *Base = I.getType()->getAsCXXRecordDecl();
2101 Base = Base->getDefinition();
2105 if (Base->getCanonicalDecl() == Class)
2108 Queue.push_back(Base);
2114 Current = Queue.pop_back_val();
2120 /// \brief Check the validity of a C++ base class specifier.
2122 /// \returns a new CXXBaseSpecifier if well-formed, emits diagnostics
2123 /// and returns NULL otherwise.
2125 Sema::CheckBaseSpecifier(CXXRecordDecl *Class,
2126 SourceRange SpecifierRange,
2127 bool Virtual, AccessSpecifier Access,
2128 TypeSourceInfo *TInfo,
2129 SourceLocation EllipsisLoc) {
2130 QualType BaseType = TInfo->getType();
2132 // C++ [class.union]p1:
2133 // A union shall not have base classes.
2134 if (Class->isUnion()) {
2135 Diag(Class->getLocation(), diag::err_base_clause_on_union)
2140 if (EllipsisLoc.isValid() &&
2141 !TInfo->getType()->containsUnexpandedParameterPack()) {
2142 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
2143 << TInfo->getTypeLoc().getSourceRange();
2144 EllipsisLoc = SourceLocation();
2147 SourceLocation BaseLoc = TInfo->getTypeLoc().getBeginLoc();
2149 if (BaseType->isDependentType()) {
2150 // Make sure that we don't have circular inheritance among our dependent
2151 // bases. For non-dependent bases, the check for completeness below handles
2153 if (CXXRecordDecl *BaseDecl = BaseType->getAsCXXRecordDecl()) {
2154 if (BaseDecl->getCanonicalDecl() == Class->getCanonicalDecl() ||
2155 ((BaseDecl = BaseDecl->getDefinition()) &&
2156 findCircularInheritance(Class, BaseDecl))) {
2157 Diag(BaseLoc, diag::err_circular_inheritance)
2158 << BaseType << Context.getTypeDeclType(Class);
2160 if (BaseDecl->getCanonicalDecl() != Class->getCanonicalDecl())
2161 Diag(BaseDecl->getLocation(), diag::note_previous_decl)
2168 return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
2169 Class->getTagKind() == TTK_Class,
2170 Access, TInfo, EllipsisLoc);
2173 // Base specifiers must be record types.
2174 if (!BaseType->isRecordType()) {
2175 Diag(BaseLoc, diag::err_base_must_be_class) << SpecifierRange;
2179 // C++ [class.union]p1:
2180 // A union shall not be used as a base class.
2181 if (BaseType->isUnionType()) {
2182 Diag(BaseLoc, diag::err_union_as_base_class) << SpecifierRange;
2186 // For the MS ABI, propagate DLL attributes to base class templates.
2187 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
2188 if (Attr *ClassAttr = getDLLAttr(Class)) {
2189 if (auto *BaseTemplate = dyn_cast_or_null<ClassTemplateSpecializationDecl>(
2190 BaseType->getAsCXXRecordDecl())) {
2191 propagateDLLAttrToBaseClassTemplate(Class, ClassAttr, BaseTemplate,
2197 // C++ [class.derived]p2:
2198 // The class-name in a base-specifier shall not be an incompletely
2200 if (RequireCompleteType(BaseLoc, BaseType,
2201 diag::err_incomplete_base_class, SpecifierRange)) {
2202 Class->setInvalidDecl();
2206 // If the base class is polymorphic or isn't empty, the new one is/isn't, too.
2207 RecordDecl *BaseDecl = BaseType->getAs<RecordType>()->getDecl();
2208 assert(BaseDecl && "Record type has no declaration");
2209 BaseDecl = BaseDecl->getDefinition();
2210 assert(BaseDecl && "Base type is not incomplete, but has no definition");
2211 CXXRecordDecl *CXXBaseDecl = cast<CXXRecordDecl>(BaseDecl);
2212 assert(CXXBaseDecl && "Base type is not a C++ type");
2214 // A class which contains a flexible array member is not suitable for use as a
2216 // - If the layout determines that a base comes before another base,
2217 // the flexible array member would index into the subsequent base.
2218 // - If the layout determines that base comes before the derived class,
2219 // the flexible array member would index into the derived class.
2220 if (CXXBaseDecl->hasFlexibleArrayMember()) {
2221 Diag(BaseLoc, diag::err_base_class_has_flexible_array_member)
2222 << CXXBaseDecl->getDeclName();
2227 // If a class is marked final and it appears as a base-type-specifier in
2228 // base-clause, the program is ill-formed.
2229 if (FinalAttr *FA = CXXBaseDecl->getAttr<FinalAttr>()) {
2230 Diag(BaseLoc, diag::err_class_marked_final_used_as_base)
2231 << CXXBaseDecl->getDeclName()
2232 << FA->isSpelledAsSealed();
2233 Diag(CXXBaseDecl->getLocation(), diag::note_entity_declared_at)
2234 << CXXBaseDecl->getDeclName() << FA->getRange();
2238 if (BaseDecl->isInvalidDecl())
2239 Class->setInvalidDecl();
2241 // Create the base specifier.
2242 return new (Context) CXXBaseSpecifier(SpecifierRange, Virtual,
2243 Class->getTagKind() == TTK_Class,
2244 Access, TInfo, EllipsisLoc);
2247 /// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is
2248 /// one entry in the base class list of a class specifier, for
2250 /// class foo : public bar, virtual private baz {
2251 /// 'public bar' and 'virtual private baz' are each base-specifiers.
2253 Sema::ActOnBaseSpecifier(Decl *classdecl, SourceRange SpecifierRange,
2254 ParsedAttributes &Attributes,
2255 bool Virtual, AccessSpecifier Access,
2256 ParsedType basetype, SourceLocation BaseLoc,
2257 SourceLocation EllipsisLoc) {
2261 AdjustDeclIfTemplate(classdecl);
2262 CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(classdecl);
2266 // We haven't yet attached the base specifiers.
2267 Class->setIsParsingBaseSpecifiers();
2269 // We do not support any C++11 attributes on base-specifiers yet.
2270 // Diagnose any attributes we see.
2271 if (!Attributes.empty()) {
2272 for (AttributeList *Attr = Attributes.getList(); Attr;
2273 Attr = Attr->getNext()) {
2274 if (Attr->isInvalid() ||
2275 Attr->getKind() == AttributeList::IgnoredAttribute)
2277 Diag(Attr->getLoc(),
2278 Attr->getKind() == AttributeList::UnknownAttribute
2279 ? diag::warn_unknown_attribute_ignored
2280 : diag::err_base_specifier_attribute)
2285 TypeSourceInfo *TInfo = nullptr;
2286 GetTypeFromParser(basetype, &TInfo);
2288 if (EllipsisLoc.isInvalid() &&
2289 DiagnoseUnexpandedParameterPack(SpecifierRange.getBegin(), TInfo,
2293 if (CXXBaseSpecifier *BaseSpec = CheckBaseSpecifier(Class, SpecifierRange,
2294 Virtual, Access, TInfo,
2298 Class->setInvalidDecl();
2303 /// Use small set to collect indirect bases. As this is only used
2304 /// locally, there's no need to abstract the small size parameter.
2305 typedef llvm::SmallPtrSet<QualType, 4> IndirectBaseSet;
2307 /// \brief Recursively add the bases of Type. Don't add Type itself.
2309 NoteIndirectBases(ASTContext &Context, IndirectBaseSet &Set,
2310 const QualType &Type)
2312 // Even though the incoming type is a base, it might not be
2313 // a class -- it could be a template parm, for instance.
2314 if (auto Rec = Type->getAs<RecordType>()) {
2315 auto Decl = Rec->getAsCXXRecordDecl();
2317 // Iterate over its bases.
2318 for (const auto &BaseSpec : Decl->bases()) {
2319 QualType Base = Context.getCanonicalType(BaseSpec.getType())
2320 .getUnqualifiedType();
2321 if (Set.insert(Base).second)
2322 // If we've not already seen it, recurse.
2323 NoteIndirectBases(Context, Set, Base);
2328 /// \brief Performs the actual work of attaching the given base class
2329 /// specifiers to a C++ class.
2330 bool Sema::AttachBaseSpecifiers(CXXRecordDecl *Class,
2331 MutableArrayRef<CXXBaseSpecifier *> Bases) {
2335 // Used to keep track of which base types we have already seen, so
2336 // that we can properly diagnose redundant direct base types. Note
2337 // that the key is always the unqualified canonical type of the base
2339 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes;
2341 // Used to track indirect bases so we can see if a direct base is
2343 IndirectBaseSet IndirectBaseTypes;
2345 // Copy non-redundant base specifiers into permanent storage.
2346 unsigned NumGoodBases = 0;
2347 bool Invalid = false;
2348 for (unsigned idx = 0; idx < Bases.size(); ++idx) {
2349 QualType NewBaseType
2350 = Context.getCanonicalType(Bases[idx]->getType());
2351 NewBaseType = NewBaseType.getLocalUnqualifiedType();
2353 CXXBaseSpecifier *&KnownBase = KnownBaseTypes[NewBaseType];
2355 // C++ [class.mi]p3:
2356 // A class shall not be specified as a direct base class of a
2357 // derived class more than once.
2358 Diag(Bases[idx]->getLocStart(),
2359 diag::err_duplicate_base_class)
2360 << KnownBase->getType()
2361 << Bases[idx]->getSourceRange();
2363 // Delete the duplicate base class specifier; we're going to
2364 // overwrite its pointer later.
2365 Context.Deallocate(Bases[idx]);
2369 // Okay, add this new base class.
2370 KnownBase = Bases[idx];
2371 Bases[NumGoodBases++] = Bases[idx];
2373 // Note this base's direct & indirect bases, if there could be ambiguity.
2374 if (Bases.size() > 1)
2375 NoteIndirectBases(Context, IndirectBaseTypes, NewBaseType);
2377 if (const RecordType *Record = NewBaseType->getAs<RecordType>()) {
2378 const CXXRecordDecl *RD = cast<CXXRecordDecl>(Record->getDecl());
2379 if (Class->isInterface() &&
2380 (!RD->isInterface() ||
2381 KnownBase->getAccessSpecifier() != AS_public)) {
2382 // The Microsoft extension __interface does not permit bases that
2383 // are not themselves public interfaces.
2384 Diag(KnownBase->getLocStart(), diag::err_invalid_base_in_interface)
2385 << getRecordDiagFromTagKind(RD->getTagKind()) << RD->getName()
2386 << RD->getSourceRange();
2389 if (RD->hasAttr<WeakAttr>())
2390 Class->addAttr(WeakAttr::CreateImplicit(Context));
2395 // Attach the remaining base class specifiers to the derived class.
2396 Class->setBases(Bases.data(), NumGoodBases);
2398 for (unsigned idx = 0; idx < NumGoodBases; ++idx) {
2399 // Check whether this direct base is inaccessible due to ambiguity.
2400 QualType BaseType = Bases[idx]->getType();
2401 CanQualType CanonicalBase = Context.getCanonicalType(BaseType)
2402 .getUnqualifiedType();
2404 if (IndirectBaseTypes.count(CanonicalBase)) {
2405 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2406 /*DetectVirtual=*/true);
2408 = Class->isDerivedFrom(CanonicalBase->getAsCXXRecordDecl(), Paths);
2412 if (Paths.isAmbiguous(CanonicalBase))
2413 Diag(Bases[idx]->getLocStart (), diag::warn_inaccessible_base_class)
2414 << BaseType << getAmbiguousPathsDisplayString(Paths)
2415 << Bases[idx]->getSourceRange();
2417 assert(Bases[idx]->isVirtual());
2420 // Delete the base class specifier, since its data has been copied
2421 // into the CXXRecordDecl.
2422 Context.Deallocate(Bases[idx]);
2428 /// ActOnBaseSpecifiers - Attach the given base specifiers to the
2429 /// class, after checking whether there are any duplicate base
2431 void Sema::ActOnBaseSpecifiers(Decl *ClassDecl,
2432 MutableArrayRef<CXXBaseSpecifier *> Bases) {
2433 if (!ClassDecl || Bases.empty())
2436 AdjustDeclIfTemplate(ClassDecl);
2437 AttachBaseSpecifiers(cast<CXXRecordDecl>(ClassDecl), Bases);
2440 /// \brief Determine whether the type \p Derived is a C++ class that is
2441 /// derived from the type \p Base.
2442 bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base) {
2443 if (!getLangOpts().CPlusPlus)
2446 CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
2450 CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
2454 // If either the base or the derived type is invalid, don't try to
2455 // check whether one is derived from the other.
2456 if (BaseRD->isInvalidDecl() || DerivedRD->isInvalidDecl())
2459 // FIXME: In a modules build, do we need the entire path to be visible for us
2460 // to be able to use the inheritance relationship?
2461 if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
2464 return DerivedRD->isDerivedFrom(BaseRD);
2467 /// \brief Determine whether the type \p Derived is a C++ class that is
2468 /// derived from the type \p Base.
2469 bool Sema::IsDerivedFrom(SourceLocation Loc, QualType Derived, QualType Base,
2470 CXXBasePaths &Paths) {
2471 if (!getLangOpts().CPlusPlus)
2474 CXXRecordDecl *DerivedRD = Derived->getAsCXXRecordDecl();
2478 CXXRecordDecl *BaseRD = Base->getAsCXXRecordDecl();
2482 if (!isCompleteType(Loc, Derived) && !DerivedRD->isBeingDefined())
2485 return DerivedRD->isDerivedFrom(BaseRD, Paths);
2488 void Sema::BuildBasePathArray(const CXXBasePaths &Paths,
2489 CXXCastPath &BasePathArray) {
2490 assert(BasePathArray.empty() && "Base path array must be empty!");
2491 assert(Paths.isRecordingPaths() && "Must record paths!");
2493 const CXXBasePath &Path = Paths.front();
2495 // We first go backward and check if we have a virtual base.
2496 // FIXME: It would be better if CXXBasePath had the base specifier for
2497 // the nearest virtual base.
2499 for (unsigned I = Path.size(); I != 0; --I) {
2500 if (Path[I - 1].Base->isVirtual()) {
2506 // Now add all bases.
2507 for (unsigned I = Start, E = Path.size(); I != E; ++I)
2508 BasePathArray.push_back(const_cast<CXXBaseSpecifier*>(Path[I].Base));
2511 /// CheckDerivedToBaseConversion - Check whether the Derived-to-Base
2512 /// conversion (where Derived and Base are class types) is
2513 /// well-formed, meaning that the conversion is unambiguous (and
2514 /// that all of the base classes are accessible). Returns true
2515 /// and emits a diagnostic if the code is ill-formed, returns false
2516 /// otherwise. Loc is the location where this routine should point to
2517 /// if there is an error, and Range is the source range to highlight
2518 /// if there is an error.
2520 /// If either InaccessibleBaseID or AmbigiousBaseConvID are 0, then the
2521 /// diagnostic for the respective type of error will be suppressed, but the
2522 /// check for ill-formed code will still be performed.
2524 Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
2525 unsigned InaccessibleBaseID,
2526 unsigned AmbigiousBaseConvID,
2527 SourceLocation Loc, SourceRange Range,
2528 DeclarationName Name,
2529 CXXCastPath *BasePath,
2530 bool IgnoreAccess) {
2531 // First, determine whether the path from Derived to Base is
2532 // ambiguous. This is slightly more expensive than checking whether
2533 // the Derived to Base conversion exists, because here we need to
2534 // explore multiple paths to determine if there is an ambiguity.
2535 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2536 /*DetectVirtual=*/false);
2537 bool DerivationOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
2538 assert(DerivationOkay &&
2539 "Can only be used with a derived-to-base conversion");
2540 (void)DerivationOkay;
2542 if (!Paths.isAmbiguous(Context.getCanonicalType(Base).getUnqualifiedType())) {
2543 if (!IgnoreAccess) {
2544 // Check that the base class can be accessed.
2545 switch (CheckBaseClassAccess(Loc, Base, Derived, Paths.front(),
2546 InaccessibleBaseID)) {
2547 case AR_inaccessible:
2556 // Build a base path if necessary.
2558 BuildBasePathArray(Paths, *BasePath);
2562 if (AmbigiousBaseConvID) {
2563 // We know that the derived-to-base conversion is ambiguous, and
2564 // we're going to produce a diagnostic. Perform the derived-to-base
2565 // search just one more time to compute all of the possible paths so
2566 // that we can print them out. This is more expensive than any of
2567 // the previous derived-to-base checks we've done, but at this point
2568 // performance isn't as much of an issue.
2570 Paths.setRecordingPaths(true);
2571 bool StillOkay = IsDerivedFrom(Loc, Derived, Base, Paths);
2572 assert(StillOkay && "Can only be used with a derived-to-base conversion");
2575 // Build up a textual representation of the ambiguous paths, e.g.,
2576 // D -> B -> A, that will be used to illustrate the ambiguous
2577 // conversions in the diagnostic. We only print one of the paths
2578 // to each base class subobject.
2579 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths);
2581 Diag(Loc, AmbigiousBaseConvID)
2582 << Derived << Base << PathDisplayStr << Range << Name;
2588 Sema::CheckDerivedToBaseConversion(QualType Derived, QualType Base,
2589 SourceLocation Loc, SourceRange Range,
2590 CXXCastPath *BasePath,
2591 bool IgnoreAccess) {
2592 return CheckDerivedToBaseConversion(
2593 Derived, Base, diag::err_upcast_to_inaccessible_base,
2594 diag::err_ambiguous_derived_to_base_conv, Loc, Range, DeclarationName(),
2595 BasePath, IgnoreAccess);
2599 /// @brief Builds a string representing ambiguous paths from a
2600 /// specific derived class to different subobjects of the same base
2603 /// This function builds a string that can be used in error messages
2604 /// to show the different paths that one can take through the
2605 /// inheritance hierarchy to go from the derived class to different
2606 /// subobjects of a base class. The result looks something like this:
2608 /// struct D -> struct B -> struct A
2609 /// struct D -> struct C -> struct A
2611 std::string Sema::getAmbiguousPathsDisplayString(CXXBasePaths &Paths) {
2612 std::string PathDisplayStr;
2613 std::set<unsigned> DisplayedPaths;
2614 for (CXXBasePaths::paths_iterator Path = Paths.begin();
2615 Path != Paths.end(); ++Path) {
2616 if (DisplayedPaths.insert(Path->back().SubobjectNumber).second) {
2617 // We haven't displayed a path to this particular base
2618 // class subobject yet.
2619 PathDisplayStr += "\n ";
2620 PathDisplayStr += Context.getTypeDeclType(Paths.getOrigin()).getAsString();
2621 for (CXXBasePath::const_iterator Element = Path->begin();
2622 Element != Path->end(); ++Element)
2623 PathDisplayStr += " -> " + Element->Base->getType().getAsString();
2627 return PathDisplayStr;
2630 //===----------------------------------------------------------------------===//
2631 // C++ class member Handling
2632 //===----------------------------------------------------------------------===//
2634 /// ActOnAccessSpecifier - Parsed an access specifier followed by a colon.
2635 bool Sema::ActOnAccessSpecifier(AccessSpecifier Access,
2636 SourceLocation ASLoc,
2637 SourceLocation ColonLoc,
2638 AttributeList *Attrs) {
2639 assert(Access != AS_none && "Invalid kind for syntactic access specifier!");
2640 AccessSpecDecl *ASDecl = AccessSpecDecl::Create(Context, Access, CurContext,
2642 CurContext->addHiddenDecl(ASDecl);
2643 return ProcessAccessDeclAttributeList(ASDecl, Attrs);
2646 /// CheckOverrideControl - Check C++11 override control semantics.
2647 void Sema::CheckOverrideControl(NamedDecl *D) {
2648 if (D->isInvalidDecl())
2651 // We only care about "override" and "final" declarations.
2652 if (!D->hasAttr<OverrideAttr>() && !D->hasAttr<FinalAttr>())
2655 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
2657 // We can't check dependent instance methods.
2658 if (MD && MD->isInstance() &&
2659 (MD->getParent()->hasAnyDependentBases() ||
2660 MD->getType()->isDependentType()))
2663 if (MD && !MD->isVirtual()) {
2664 // If we have a non-virtual method, check if if hides a virtual method.
2665 // (In that case, it's most likely the method has the wrong type.)
2666 SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
2667 FindHiddenVirtualMethods(MD, OverloadedMethods);
2669 if (!OverloadedMethods.empty()) {
2670 if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
2671 Diag(OA->getLocation(),
2672 diag::override_keyword_hides_virtual_member_function)
2673 << "override" << (OverloadedMethods.size() > 1);
2674 } else if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
2675 Diag(FA->getLocation(),
2676 diag::override_keyword_hides_virtual_member_function)
2677 << (FA->isSpelledAsSealed() ? "sealed" : "final")
2678 << (OverloadedMethods.size() > 1);
2680 NoteHiddenVirtualMethods(MD, OverloadedMethods);
2681 MD->setInvalidDecl();
2684 // Fall through into the general case diagnostic.
2685 // FIXME: We might want to attempt typo correction here.
2688 if (!MD || !MD->isVirtual()) {
2689 if (OverrideAttr *OA = D->getAttr<OverrideAttr>()) {
2690 Diag(OA->getLocation(),
2691 diag::override_keyword_only_allowed_on_virtual_member_functions)
2692 << "override" << FixItHint::CreateRemoval(OA->getLocation());
2693 D->dropAttr<OverrideAttr>();
2695 if (FinalAttr *FA = D->getAttr<FinalAttr>()) {
2696 Diag(FA->getLocation(),
2697 diag::override_keyword_only_allowed_on_virtual_member_functions)
2698 << (FA->isSpelledAsSealed() ? "sealed" : "final")
2699 << FixItHint::CreateRemoval(FA->getLocation());
2700 D->dropAttr<FinalAttr>();
2705 // C++11 [class.virtual]p5:
2706 // If a function is marked with the virt-specifier override and
2707 // does not override a member function of a base class, the program is
2709 bool HasOverriddenMethods =
2710 MD->begin_overridden_methods() != MD->end_overridden_methods();
2711 if (MD->hasAttr<OverrideAttr>() && !HasOverriddenMethods)
2712 Diag(MD->getLocation(), diag::err_function_marked_override_not_overriding)
2713 << MD->getDeclName();
2716 void Sema::DiagnoseAbsenceOfOverrideControl(NamedDecl *D) {
2717 if (D->isInvalidDecl() || D->hasAttr<OverrideAttr>())
2719 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D);
2720 if (!MD || MD->isImplicit() || MD->hasAttr<FinalAttr>())
2723 SourceLocation Loc = MD->getLocation();
2724 SourceLocation SpellingLoc = Loc;
2725 if (getSourceManager().isMacroArgExpansion(Loc))
2726 SpellingLoc = getSourceManager().getImmediateExpansionRange(Loc).first;
2727 SpellingLoc = getSourceManager().getSpellingLoc(SpellingLoc);
2728 if (SpellingLoc.isValid() && getSourceManager().isInSystemHeader(SpellingLoc))
2731 if (MD->size_overridden_methods() > 0) {
2732 unsigned DiagID = isa<CXXDestructorDecl>(MD)
2733 ? diag::warn_destructor_marked_not_override_overriding
2734 : diag::warn_function_marked_not_override_overriding;
2735 Diag(MD->getLocation(), DiagID) << MD->getDeclName();
2736 const CXXMethodDecl *OMD = *MD->begin_overridden_methods();
2737 Diag(OMD->getLocation(), diag::note_overridden_virtual_function);
2741 /// CheckIfOverriddenFunctionIsMarkedFinal - Checks whether a virtual member
2742 /// function overrides a virtual member function marked 'final', according to
2743 /// C++11 [class.virtual]p4.
2744 bool Sema::CheckIfOverriddenFunctionIsMarkedFinal(const CXXMethodDecl *New,
2745 const CXXMethodDecl *Old) {
2746 FinalAttr *FA = Old->getAttr<FinalAttr>();
2750 Diag(New->getLocation(), diag::err_final_function_overridden)
2751 << New->getDeclName()
2752 << FA->isSpelledAsSealed();
2753 Diag(Old->getLocation(), diag::note_overridden_virtual_function);
2757 static bool InitializationHasSideEffects(const FieldDecl &FD) {
2758 const Type *T = FD.getType()->getBaseElementTypeUnsafe();
2759 // FIXME: Destruction of ObjC lifetime types has side-effects.
2760 if (const CXXRecordDecl *RD = T->getAsCXXRecordDecl())
2761 return !RD->isCompleteDefinition() ||
2762 !RD->hasTrivialDefaultConstructor() ||
2763 !RD->hasTrivialDestructor();
2767 static AttributeList *getMSPropertyAttr(AttributeList *list) {
2768 for (AttributeList *it = list; it != nullptr; it = it->getNext())
2769 if (it->isDeclspecPropertyAttribute())
2774 // Check if there is a field shadowing.
2775 void Sema::CheckShadowInheritedFields(const SourceLocation &Loc,
2776 DeclarationName FieldName,
2777 const CXXRecordDecl *RD) {
2778 if (Diags.isIgnored(diag::warn_shadow_field, Loc))
2781 // To record a shadowed field in a base
2782 std::map<CXXRecordDecl*, NamedDecl*> Bases;
2783 auto FieldShadowed = [&](const CXXBaseSpecifier *Specifier,
2784 CXXBasePath &Path) {
2785 const auto Base = Specifier->getType()->getAsCXXRecordDecl();
2786 // Record an ambiguous path directly
2787 if (Bases.find(Base) != Bases.end())
2789 for (const auto Field : Base->lookup(FieldName)) {
2790 if ((isa<FieldDecl>(Field) || isa<IndirectFieldDecl>(Field)) &&
2791 Field->getAccess() != AS_private) {
2792 assert(Field->getAccess() != AS_none);
2793 assert(Bases.find(Base) == Bases.end());
2794 Bases[Base] = Field;
2801 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
2802 /*DetectVirtual=*/true);
2803 if (!RD->lookupInBases(FieldShadowed, Paths))
2806 for (const auto &P : Paths) {
2807 auto Base = P.back().Base->getType()->getAsCXXRecordDecl();
2808 auto It = Bases.find(Base);
2809 // Skip duplicated bases
2810 if (It == Bases.end())
2812 auto BaseField = It->second;
2813 assert(BaseField->getAccess() != AS_private);
2815 CXXRecordDecl::MergeAccess(P.Access, BaseField->getAccess())) {
2816 Diag(Loc, diag::warn_shadow_field)
2817 << FieldName.getAsString() << RD->getName() << Base->getName();
2818 Diag(BaseField->getLocation(), diag::note_shadow_field);
2824 /// ActOnCXXMemberDeclarator - This is invoked when a C++ class member
2825 /// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the
2826 /// bitfield width if there is one, 'InitExpr' specifies the initializer if
2827 /// one has been parsed, and 'InitStyle' is set if an in-class initializer is
2828 /// present (but parsing it has been deferred).
2830 Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D,
2831 MultiTemplateParamsArg TemplateParameterLists,
2832 Expr *BW, const VirtSpecifiers &VS,
2833 InClassInitStyle InitStyle) {
2834 const DeclSpec &DS = D.getDeclSpec();
2835 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
2836 DeclarationName Name = NameInfo.getName();
2837 SourceLocation Loc = NameInfo.getLoc();
2839 // For anonymous bitfields, the location should point to the type.
2840 if (Loc.isInvalid())
2841 Loc = D.getLocStart();
2843 Expr *BitWidth = static_cast<Expr*>(BW);
2845 assert(isa<CXXRecordDecl>(CurContext));
2846 assert(!DS.isFriendSpecified());
2848 bool isFunc = D.isDeclarationOfFunction();
2850 if (cast<CXXRecordDecl>(CurContext)->isInterface()) {
2851 // The Microsoft extension __interface only permits public member functions
2852 // and prohibits constructors, destructors, operators, non-public member
2853 // functions, static methods and data members.
2854 unsigned InvalidDecl;
2855 bool ShowDeclName = true;
2857 InvalidDecl = (DS.getStorageClassSpec() == DeclSpec::SCS_typedef) ? 0 : 1;
2858 else if (AS != AS_public)
2860 else if (DS.getStorageClassSpec() == DeclSpec::SCS_static)
2862 else switch (Name.getNameKind()) {
2863 case DeclarationName::CXXConstructorName:
2865 ShowDeclName = false;
2868 case DeclarationName::CXXDestructorName:
2870 ShowDeclName = false;
2873 case DeclarationName::CXXOperatorName:
2874 case DeclarationName::CXXConversionFunctionName:
2885 Diag(Loc, diag::err_invalid_member_in_interface)
2886 << (InvalidDecl-1) << Name;
2888 Diag(Loc, diag::err_invalid_member_in_interface)
2889 << (InvalidDecl-1) << "";
2894 // C++ 9.2p6: A member shall not be declared to have automatic storage
2895 // duration (auto, register) or with the extern storage-class-specifier.
2896 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class
2897 // data members and cannot be applied to names declared const or static,
2898 // and cannot be applied to reference members.
2899 switch (DS.getStorageClassSpec()) {
2900 case DeclSpec::SCS_unspecified:
2901 case DeclSpec::SCS_typedef:
2902 case DeclSpec::SCS_static:
2904 case DeclSpec::SCS_mutable:
2906 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_function);
2908 // FIXME: It would be nicer if the keyword was ignored only for this
2909 // declarator. Otherwise we could get follow-up errors.
2910 D.getMutableDeclSpec().ClearStorageClassSpecs();
2914 Diag(DS.getStorageClassSpecLoc(),
2915 diag::err_storageclass_invalid_for_member);
2916 D.getMutableDeclSpec().ClearStorageClassSpecs();
2920 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified ||
2921 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) &&
2924 if (DS.isConstexprSpecified() && isInstField) {
2925 SemaDiagnosticBuilder B =
2926 Diag(DS.getConstexprSpecLoc(), diag::err_invalid_constexpr_member);
2927 SourceLocation ConstexprLoc = DS.getConstexprSpecLoc();
2928 if (InitStyle == ICIS_NoInit) {
2930 if (D.getDeclSpec().getTypeQualifiers() & DeclSpec::TQ_const)
2931 B << FixItHint::CreateRemoval(ConstexprLoc);
2933 B << FixItHint::CreateReplacement(ConstexprLoc, "const");
2934 D.getMutableDeclSpec().ClearConstexprSpec();
2935 const char *PrevSpec;
2937 bool Failed = D.getMutableDeclSpec().SetTypeQual(
2938 DeclSpec::TQ_const, ConstexprLoc, PrevSpec, DiagID, getLangOpts());
2940 assert(!Failed && "Making a constexpr member const shouldn't fail");
2944 const char *PrevSpec;
2946 if (D.getMutableDeclSpec().SetStorageClassSpec(
2947 *this, DeclSpec::SCS_static, ConstexprLoc, PrevSpec, DiagID,
2948 Context.getPrintingPolicy())) {
2949 assert(DS.getStorageClassSpec() == DeclSpec::SCS_mutable &&
2950 "This is the only DeclSpec that should fail to be applied");
2953 B << 0 << FixItHint::CreateInsertion(ConstexprLoc, "static ");
2954 isInstField = false;
2961 CXXScopeSpec &SS = D.getCXXScopeSpec();
2963 // Data members must have identifiers for names.
2964 if (!Name.isIdentifier()) {
2965 Diag(Loc, diag::err_bad_variable_name)
2970 IdentifierInfo *II = Name.getAsIdentifierInfo();
2972 // Member field could not be with "template" keyword.
2973 // So TemplateParameterLists should be empty in this case.
2974 if (TemplateParameterLists.size()) {
2975 TemplateParameterList* TemplateParams = TemplateParameterLists[0];
2976 if (TemplateParams->size()) {
2977 // There is no such thing as a member field template.
2978 Diag(D.getIdentifierLoc(), diag::err_template_member)
2980 << SourceRange(TemplateParams->getTemplateLoc(),
2981 TemplateParams->getRAngleLoc());
2983 // There is an extraneous 'template<>' for this member.
2984 Diag(TemplateParams->getTemplateLoc(),
2985 diag::err_template_member_noparams)
2987 << SourceRange(TemplateParams->getTemplateLoc(),
2988 TemplateParams->getRAngleLoc());
2993 if (SS.isSet() && !SS.isInvalid()) {
2994 // The user provided a superfluous scope specifier inside a class
3000 if (DeclContext *DC = computeDeclContext(SS, false))
3001 diagnoseQualifiedDeclaration(SS, DC, Name, D.getIdentifierLoc());
3003 Diag(D.getIdentifierLoc(), diag::err_member_qualification)
3004 << Name << SS.getRange();
3009 AttributeList *MSPropertyAttr =
3010 getMSPropertyAttr(D.getDeclSpec().getAttributes().getList());
3011 if (MSPropertyAttr) {
3012 Member = HandleMSProperty(S, cast<CXXRecordDecl>(CurContext), Loc, D,
3013 BitWidth, InitStyle, AS, MSPropertyAttr);
3016 isInstField = false;
3018 Member = HandleField(S, cast<CXXRecordDecl>(CurContext), Loc, D,
3019 BitWidth, InitStyle, AS);
3024 CheckShadowInheritedFields(Loc, Name, cast<CXXRecordDecl>(CurContext));
3026 Member = HandleDeclarator(S, D, TemplateParameterLists);
3030 // Non-instance-fields can't have a bitfield.
3032 if (Member->isInvalidDecl()) {
3033 // don't emit another diagnostic.
3034 } else if (isa<VarDecl>(Member) || isa<VarTemplateDecl>(Member)) {
3035 // C++ 9.6p3: A bit-field shall not be a static member.
3036 // "static member 'A' cannot be a bit-field"
3037 Diag(Loc, diag::err_static_not_bitfield)
3038 << Name << BitWidth->getSourceRange();
3039 } else if (isa<TypedefDecl>(Member)) {
3040 // "typedef member 'x' cannot be a bit-field"
3041 Diag(Loc, diag::err_typedef_not_bitfield)
3042 << Name << BitWidth->getSourceRange();
3044 // A function typedef ("typedef int f(); f a;").
3045 // C++ 9.6p3: A bit-field shall have integral or enumeration type.
3046 Diag(Loc, diag::err_not_integral_type_bitfield)
3047 << Name << cast<ValueDecl>(Member)->getType()
3048 << BitWidth->getSourceRange();
3052 Member->setInvalidDecl();
3055 Member->setAccess(AS);
3057 // If we have declared a member function template or static data member
3058 // template, set the access of the templated declaration as well.
3059 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(Member))
3060 FunTmpl->getTemplatedDecl()->setAccess(AS);
3061 else if (VarTemplateDecl *VarTmpl = dyn_cast<VarTemplateDecl>(Member))
3062 VarTmpl->getTemplatedDecl()->setAccess(AS);
3065 if (VS.isOverrideSpecified())
3066 Member->addAttr(new (Context) OverrideAttr(VS.getOverrideLoc(), Context, 0));
3067 if (VS.isFinalSpecified())
3068 Member->addAttr(new (Context) FinalAttr(VS.getFinalLoc(), Context,
3069 VS.isFinalSpelledSealed()));
3071 if (VS.getLastLocation().isValid()) {
3072 // Update the end location of a method that has a virt-specifiers.
3073 if (CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Member))
3074 MD->setRangeEnd(VS.getLastLocation());
3077 CheckOverrideControl(Member);
3079 assert((Name || isInstField) && "No identifier for non-field ?");
3082 FieldDecl *FD = cast<FieldDecl>(Member);
3083 FieldCollector->Add(FD);
3085 if (!Diags.isIgnored(diag::warn_unused_private_field, FD->getLocation())) {
3086 // Remember all explicit private FieldDecls that have a name, no side
3087 // effects and are not part of a dependent type declaration.
3088 if (!FD->isImplicit() && FD->getDeclName() &&
3089 FD->getAccess() == AS_private &&
3090 !FD->hasAttr<UnusedAttr>() &&
3091 !FD->getParent()->isDependentContext() &&
3092 !InitializationHasSideEffects(*FD))
3093 UnusedPrivateFields.insert(FD);
3101 class UninitializedFieldVisitor
3102 : public EvaluatedExprVisitor<UninitializedFieldVisitor> {
3104 // List of Decls to generate a warning on. Also remove Decls that become
3106 llvm::SmallPtrSetImpl<ValueDecl*> &Decls;
3107 // List of base classes of the record. Classes are removed after their
3109 llvm::SmallPtrSetImpl<QualType> &BaseClasses;
3110 // Vector of decls to be removed from the Decl set prior to visiting the
3111 // nodes. These Decls may have been initialized in the prior initializer.
3112 llvm::SmallVector<ValueDecl*, 4> DeclsToRemove;
3113 // If non-null, add a note to the warning pointing back to the constructor.
3114 const CXXConstructorDecl *Constructor;
3115 // Variables to hold state when processing an initializer list. When
3116 // InitList is true, special case initialization of FieldDecls matching
3117 // InitListFieldDecl.
3119 FieldDecl *InitListFieldDecl;
3120 llvm::SmallVector<unsigned, 4> InitFieldIndex;
3123 typedef EvaluatedExprVisitor<UninitializedFieldVisitor> Inherited;
3124 UninitializedFieldVisitor(Sema &S,
3125 llvm::SmallPtrSetImpl<ValueDecl*> &Decls,
3126 llvm::SmallPtrSetImpl<QualType> &BaseClasses)
3127 : Inherited(S.Context), S(S), Decls(Decls), BaseClasses(BaseClasses),
3128 Constructor(nullptr), InitList(false), InitListFieldDecl(nullptr) {}
3130 // Returns true if the use of ME is not an uninitialized use.
3131 bool IsInitListMemberExprInitialized(MemberExpr *ME,
3132 bool CheckReferenceOnly) {
3133 llvm::SmallVector<FieldDecl*, 4> Fields;
3134 bool ReferenceField = false;
3136 FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl());
3139 Fields.push_back(FD);
3140 if (FD->getType()->isReferenceType())
3141 ReferenceField = true;
3142 ME = dyn_cast<MemberExpr>(ME->getBase()->IgnoreParenImpCasts());
3145 // Binding a reference to an unintialized field is not an
3146 // uninitialized use.
3147 if (CheckReferenceOnly && !ReferenceField)
3150 llvm::SmallVector<unsigned, 4> UsedFieldIndex;
3151 // Discard the first field since it is the field decl that is being
3153 for (auto I = Fields.rbegin() + 1, E = Fields.rend(); I != E; ++I) {
3154 UsedFieldIndex.push_back((*I)->getFieldIndex());
3157 for (auto UsedIter = UsedFieldIndex.begin(),
3158 UsedEnd = UsedFieldIndex.end(),
3159 OrigIter = InitFieldIndex.begin(),
3160 OrigEnd = InitFieldIndex.end();
3161 UsedIter != UsedEnd && OrigIter != OrigEnd; ++UsedIter, ++OrigIter) {
3162 if (*UsedIter < *OrigIter)
3164 if (*UsedIter > *OrigIter)
3171 void HandleMemberExpr(MemberExpr *ME, bool CheckReferenceOnly,
3173 if (isa<EnumConstantDecl>(ME->getMemberDecl()))
3176 // FieldME is the inner-most MemberExpr that is not an anonymous struct
3178 MemberExpr *FieldME = ME;
3180 bool AllPODFields = FieldME->getType().isPODType(S.Context);
3183 while (MemberExpr *SubME =
3184 dyn_cast<MemberExpr>(Base->IgnoreParenImpCasts())) {
3186 if (isa<VarDecl>(SubME->getMemberDecl()))
3189 if (FieldDecl *FD = dyn_cast<FieldDecl>(SubME->getMemberDecl()))
3190 if (!FD->isAnonymousStructOrUnion())
3193 if (!FieldME->getType().isPODType(S.Context))
3194 AllPODFields = false;
3196 Base = SubME->getBase();
3199 if (!isa<CXXThisExpr>(Base->IgnoreParenImpCasts()))
3202 if (AddressOf && AllPODFields)
3205 ValueDecl* FoundVD = FieldME->getMemberDecl();
3207 if (ImplicitCastExpr *BaseCast = dyn_cast<ImplicitCastExpr>(Base)) {
3208 while (isa<ImplicitCastExpr>(BaseCast->getSubExpr())) {
3209 BaseCast = cast<ImplicitCastExpr>(BaseCast->getSubExpr());
3212 if (BaseCast->getCastKind() == CK_UncheckedDerivedToBase) {
3213 QualType T = BaseCast->getType();
3214 if (T->isPointerType() &&
3215 BaseClasses.count(T->getPointeeType())) {
3216 S.Diag(FieldME->getExprLoc(), diag::warn_base_class_is_uninit)
3217 << T->getPointeeType() << FoundVD;
3222 if (!Decls.count(FoundVD))
3225 const bool IsReference = FoundVD->getType()->isReferenceType();
3227 if (InitList && !AddressOf && FoundVD == InitListFieldDecl) {
3228 // Special checking for initializer lists.
3229 if (IsInitListMemberExprInitialized(ME, CheckReferenceOnly)) {
3233 // Prevent double warnings on use of unbounded references.
3234 if (CheckReferenceOnly && !IsReference)
3238 unsigned diag = IsReference
3239 ? diag::warn_reference_field_is_uninit
3240 : diag::warn_field_is_uninit;
3241 S.Diag(FieldME->getExprLoc(), diag) << FoundVD;
3243 S.Diag(Constructor->getLocation(),
3244 diag::note_uninit_in_this_constructor)
3245 << (Constructor->isDefaultConstructor() && Constructor->isImplicit());
3249 void HandleValue(Expr *E, bool AddressOf) {
3250 E = E->IgnoreParens();
3252 if (MemberExpr *ME = dyn_cast<MemberExpr>(E)) {
3253 HandleMemberExpr(ME, false /*CheckReferenceOnly*/,
3254 AddressOf /*AddressOf*/);
3258 if (ConditionalOperator *CO = dyn_cast<ConditionalOperator>(E)) {
3259 Visit(CO->getCond());
3260 HandleValue(CO->getTrueExpr(), AddressOf);
3261 HandleValue(CO->getFalseExpr(), AddressOf);
3265 if (BinaryConditionalOperator *BCO =
3266 dyn_cast<BinaryConditionalOperator>(E)) {
3267 Visit(BCO->getCond());
3268 HandleValue(BCO->getFalseExpr(), AddressOf);
3272 if (OpaqueValueExpr *OVE = dyn_cast<OpaqueValueExpr>(E)) {
3273 HandleValue(OVE->getSourceExpr(), AddressOf);
3277 if (BinaryOperator *BO = dyn_cast<BinaryOperator>(E)) {
3278 switch (BO->getOpcode()) {
3283 HandleValue(BO->getLHS(), AddressOf);
3284 Visit(BO->getRHS());
3287 Visit(BO->getLHS());
3288 HandleValue(BO->getRHS(), AddressOf);
3296 void CheckInitListExpr(InitListExpr *ILE) {
3297 InitFieldIndex.push_back(0);
3298 for (auto Child : ILE->children()) {
3299 if (InitListExpr *SubList = dyn_cast<InitListExpr>(Child)) {
3300 CheckInitListExpr(SubList);
3304 ++InitFieldIndex.back();
3306 InitFieldIndex.pop_back();
3309 void CheckInitializer(Expr *E, const CXXConstructorDecl *FieldConstructor,
3310 FieldDecl *Field, const Type *BaseClass) {
3311 // Remove Decls that may have been initialized in the previous
3313 for (ValueDecl* VD : DeclsToRemove)
3315 DeclsToRemove.clear();
3317 Constructor = FieldConstructor;
3318 InitListExpr *ILE = dyn_cast<InitListExpr>(E);
3322 InitListFieldDecl = Field;
3323 InitFieldIndex.clear();
3324 CheckInitListExpr(ILE);
3333 BaseClasses.erase(BaseClass->getCanonicalTypeInternal());
3336 void VisitMemberExpr(MemberExpr *ME) {
3337 // All uses of unbounded reference fields will warn.
3338 HandleMemberExpr(ME, true /*CheckReferenceOnly*/, false /*AddressOf*/);
3341 void VisitImplicitCastExpr(ImplicitCastExpr *E) {
3342 if (E->getCastKind() == CK_LValueToRValue) {
3343 HandleValue(E->getSubExpr(), false /*AddressOf*/);
3347 Inherited::VisitImplicitCastExpr(E);
3350 void VisitCXXConstructExpr(CXXConstructExpr *E) {
3351 if (E->getConstructor()->isCopyConstructor()) {
3352 Expr *ArgExpr = E->getArg(0);
3353 if (InitListExpr *ILE = dyn_cast<InitListExpr>(ArgExpr))
3354 if (ILE->getNumInits() == 1)
3355 ArgExpr = ILE->getInit(0);
3356 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(ArgExpr))
3357 if (ICE->getCastKind() == CK_NoOp)
3358 ArgExpr = ICE->getSubExpr();
3359 HandleValue(ArgExpr, false /*AddressOf*/);
3362 Inherited::VisitCXXConstructExpr(E);
3365 void VisitCXXMemberCallExpr(CXXMemberCallExpr *E) {
3366 Expr *Callee = E->getCallee();
3367 if (isa<MemberExpr>(Callee)) {
3368 HandleValue(Callee, false /*AddressOf*/);
3369 for (auto Arg : E->arguments())
3374 Inherited::VisitCXXMemberCallExpr(E);
3377 void VisitCallExpr(CallExpr *E) {
3378 // Treat std::move as a use.
3379 if (E->getNumArgs() == 1) {
3380 if (FunctionDecl *FD = E->getDirectCallee()) {
3381 if (FD->isInStdNamespace() && FD->getIdentifier() &&
3382 FD->getIdentifier()->isStr("move")) {
3383 HandleValue(E->getArg(0), false /*AddressOf*/);
3389 Inherited::VisitCallExpr(E);
3392 void VisitCXXOperatorCallExpr(CXXOperatorCallExpr *E) {
3393 Expr *Callee = E->getCallee();
3395 if (isa<UnresolvedLookupExpr>(Callee))
3396 return Inherited::VisitCXXOperatorCallExpr(E);
3399 for (auto Arg : E->arguments())
3400 HandleValue(Arg->IgnoreParenImpCasts(), false /*AddressOf*/);
3403 void VisitBinaryOperator(BinaryOperator *E) {
3404 // If a field assignment is detected, remove the field from the
3405 // uninitiailized field set.
3406 if (E->getOpcode() == BO_Assign)
3407 if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getLHS()))
3408 if (FieldDecl *FD = dyn_cast<FieldDecl>(ME->getMemberDecl()))
3409 if (!FD->getType()->isReferenceType())
3410 DeclsToRemove.push_back(FD);
3412 if (E->isCompoundAssignmentOp()) {
3413 HandleValue(E->getLHS(), false /*AddressOf*/);
3418 Inherited::VisitBinaryOperator(E);
3421 void VisitUnaryOperator(UnaryOperator *E) {
3422 if (E->isIncrementDecrementOp()) {
3423 HandleValue(E->getSubExpr(), false /*AddressOf*/);
3426 if (E->getOpcode() == UO_AddrOf) {
3427 if (MemberExpr *ME = dyn_cast<MemberExpr>(E->getSubExpr())) {
3428 HandleValue(ME->getBase(), true /*AddressOf*/);
3433 Inherited::VisitUnaryOperator(E);
3437 // Diagnose value-uses of fields to initialize themselves, e.g.
3439 // where foo is not also a parameter to the constructor.
3440 // Also diagnose across field uninitialized use such as
3442 // TODO: implement -Wuninitialized and fold this into that framework.
3443 static void DiagnoseUninitializedFields(
3444 Sema &SemaRef, const CXXConstructorDecl *Constructor) {
3446 if (SemaRef.getDiagnostics().isIgnored(diag::warn_field_is_uninit,
3447 Constructor->getLocation())) {
3451 if (Constructor->isInvalidDecl())
3454 const CXXRecordDecl *RD = Constructor->getParent();
3456 if (RD->getDescribedClassTemplate())
3459 // Holds fields that are uninitialized.
3460 llvm::SmallPtrSet<ValueDecl*, 4> UninitializedFields;
3462 // At the beginning, all fields are uninitialized.
3463 for (auto *I : RD->decls()) {
3464 if (auto *FD = dyn_cast<FieldDecl>(I)) {
3465 UninitializedFields.insert(FD);
3466 } else if (auto *IFD = dyn_cast<IndirectFieldDecl>(I)) {
3467 UninitializedFields.insert(IFD->getAnonField());
3471 llvm::SmallPtrSet<QualType, 4> UninitializedBaseClasses;
3472 for (auto I : RD->bases())
3473 UninitializedBaseClasses.insert(I.getType().getCanonicalType());
3475 if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
3478 UninitializedFieldVisitor UninitializedChecker(SemaRef,
3479 UninitializedFields,
3480 UninitializedBaseClasses);
3482 for (const auto *FieldInit : Constructor->inits()) {
3483 if (UninitializedFields.empty() && UninitializedBaseClasses.empty())
3486 Expr *InitExpr = FieldInit->getInit();
3490 if (CXXDefaultInitExpr *Default =
3491 dyn_cast<CXXDefaultInitExpr>(InitExpr)) {
3492 InitExpr = Default->getExpr();
3495 // In class initializers will point to the constructor.
3496 UninitializedChecker.CheckInitializer(InitExpr, Constructor,
3497 FieldInit->getAnyMember(),
3498 FieldInit->getBaseClass());
3500 UninitializedChecker.CheckInitializer(InitExpr, nullptr,
3501 FieldInit->getAnyMember(),
3502 FieldInit->getBaseClass());
3508 /// \brief Enter a new C++ default initializer scope. After calling this, the
3509 /// caller must call \ref ActOnFinishCXXInClassMemberInitializer, even if
3510 /// parsing or instantiating the initializer failed.
3511 void Sema::ActOnStartCXXInClassMemberInitializer() {
3512 // Create a synthetic function scope to represent the call to the constructor
3513 // that notionally surrounds a use of this initializer.
3514 PushFunctionScope();
3517 /// \brief This is invoked after parsing an in-class initializer for a
3518 /// non-static C++ class member, and after instantiating an in-class initializer
3519 /// in a class template. Such actions are deferred until the class is complete.
3520 void Sema::ActOnFinishCXXInClassMemberInitializer(Decl *D,
3521 SourceLocation InitLoc,
3523 // Pop the notional constructor scope we created earlier.
3524 PopFunctionScopeInfo(nullptr, D);
3526 FieldDecl *FD = dyn_cast<FieldDecl>(D);
3527 assert((isa<MSPropertyDecl>(D) || FD->getInClassInitStyle() != ICIS_NoInit) &&
3528 "must set init style when field is created");
3531 D->setInvalidDecl();
3533 FD->removeInClassInitializer();
3537 if (DiagnoseUnexpandedParameterPack(InitExpr, UPPC_Initializer)) {
3538 FD->setInvalidDecl();
3539 FD->removeInClassInitializer();
3543 ExprResult Init = InitExpr;
3544 if (!FD->getType()->isDependentType() && !InitExpr->isTypeDependent()) {
3545 InitializedEntity Entity = InitializedEntity::InitializeMember(FD);
3546 InitializationKind Kind = FD->getInClassInitStyle() == ICIS_ListInit
3547 ? InitializationKind::CreateDirectList(InitExpr->getLocStart())
3548 : InitializationKind::CreateCopy(InitExpr->getLocStart(), InitLoc);
3549 InitializationSequence Seq(*this, Entity, Kind, InitExpr);
3550 Init = Seq.Perform(*this, Entity, Kind, InitExpr);
3551 if (Init.isInvalid()) {
3552 FD->setInvalidDecl();
3557 // C++11 [class.base.init]p7:
3558 // The initialization of each base and member constitutes a
3560 Init = ActOnFinishFullExpr(Init.get(), InitLoc);
3561 if (Init.isInvalid()) {
3562 FD->setInvalidDecl();
3566 InitExpr = Init.get();
3568 FD->setInClassInitializer(InitExpr);
3571 /// \brief Find the direct and/or virtual base specifiers that
3572 /// correspond to the given base type, for use in base initialization
3573 /// within a constructor.
3574 static bool FindBaseInitializer(Sema &SemaRef,
3575 CXXRecordDecl *ClassDecl,
3577 const CXXBaseSpecifier *&DirectBaseSpec,
3578 const CXXBaseSpecifier *&VirtualBaseSpec) {
3579 // First, check for a direct base class.
3580 DirectBaseSpec = nullptr;
3581 for (const auto &Base : ClassDecl->bases()) {
3582 if (SemaRef.Context.hasSameUnqualifiedType(BaseType, Base.getType())) {
3583 // We found a direct base of this type. That's what we're
3585 DirectBaseSpec = &Base;
3590 // Check for a virtual base class.
3591 // FIXME: We might be able to short-circuit this if we know in advance that
3592 // there are no virtual bases.
3593 VirtualBaseSpec = nullptr;
3594 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) {
3595 // We haven't found a base yet; search the class hierarchy for a
3596 // virtual base class.
3597 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true,
3598 /*DetectVirtual=*/false);
3599 if (SemaRef.IsDerivedFrom(ClassDecl->getLocation(),
3600 SemaRef.Context.getTypeDeclType(ClassDecl),
3602 for (CXXBasePaths::paths_iterator Path = Paths.begin();
3603 Path != Paths.end(); ++Path) {
3604 if (Path->back().Base->isVirtual()) {
3605 VirtualBaseSpec = Path->back().Base;
3612 return DirectBaseSpec || VirtualBaseSpec;
3615 /// \brief Handle a C++ member initializer using braced-init-list syntax.
3617 Sema::ActOnMemInitializer(Decl *ConstructorD,
3620 IdentifierInfo *MemberOrBase,
3621 ParsedType TemplateTypeTy,
3623 SourceLocation IdLoc,
3625 SourceLocation EllipsisLoc) {
3626 return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
3627 DS, IdLoc, InitList,
3631 /// \brief Handle a C++ member initializer using parentheses syntax.
3633 Sema::ActOnMemInitializer(Decl *ConstructorD,
3636 IdentifierInfo *MemberOrBase,
3637 ParsedType TemplateTypeTy,
3639 SourceLocation IdLoc,
3640 SourceLocation LParenLoc,
3641 ArrayRef<Expr *> Args,
3642 SourceLocation RParenLoc,
3643 SourceLocation EllipsisLoc) {
3644 Expr *List = new (Context) ParenListExpr(Context, LParenLoc,
3646 return BuildMemInitializer(ConstructorD, S, SS, MemberOrBase, TemplateTypeTy,
3647 DS, IdLoc, List, EllipsisLoc);
3652 // Callback to only accept typo corrections that can be a valid C++ member
3653 // intializer: either a non-static field member or a base class.
3654 class MemInitializerValidatorCCC : public CorrectionCandidateCallback {
3656 explicit MemInitializerValidatorCCC(CXXRecordDecl *ClassDecl)
3657 : ClassDecl(ClassDecl) {}
3659 bool ValidateCandidate(const TypoCorrection &candidate) override {
3660 if (NamedDecl *ND = candidate.getCorrectionDecl()) {
3661 if (FieldDecl *Member = dyn_cast<FieldDecl>(ND))
3662 return Member->getDeclContext()->getRedeclContext()->Equals(ClassDecl);
3663 return isa<TypeDecl>(ND);
3669 CXXRecordDecl *ClassDecl;
3674 /// \brief Handle a C++ member initializer.
3676 Sema::BuildMemInitializer(Decl *ConstructorD,
3679 IdentifierInfo *MemberOrBase,
3680 ParsedType TemplateTypeTy,
3682 SourceLocation IdLoc,
3684 SourceLocation EllipsisLoc) {
3685 ExprResult Res = CorrectDelayedTyposInExpr(Init);
3686 if (!Res.isUsable())
3693 AdjustDeclIfTemplate(ConstructorD);
3695 CXXConstructorDecl *Constructor
3696 = dyn_cast<CXXConstructorDecl>(ConstructorD);
3698 // The user wrote a constructor initializer on a function that is
3699 // not a C++ constructor. Ignore the error for now, because we may
3700 // have more member initializers coming; we'll diagnose it just
3701 // once in ActOnMemInitializers.
3705 CXXRecordDecl *ClassDecl = Constructor->getParent();
3707 // C++ [class.base.init]p2:
3708 // Names in a mem-initializer-id are looked up in the scope of the
3709 // constructor's class and, if not found in that scope, are looked
3710 // up in the scope containing the constructor's definition.
3711 // [Note: if the constructor's class contains a member with the
3712 // same name as a direct or virtual base class of the class, a
3713 // mem-initializer-id naming the member or base class and composed
3714 // of a single identifier refers to the class member. A
3715 // mem-initializer-id for the hidden base class may be specified
3716 // using a qualified name. ]
3717 if (!SS.getScopeRep() && !TemplateTypeTy) {
3718 // Look for a member, first.
3719 DeclContext::lookup_result Result = ClassDecl->lookup(MemberOrBase);
3720 if (!Result.empty()) {
3722 if ((Member = dyn_cast<FieldDecl>(Result.front())) ||
3723 (Member = dyn_cast<IndirectFieldDecl>(Result.front()))) {
3724 if (EllipsisLoc.isValid())
3725 Diag(EllipsisLoc, diag::err_pack_expansion_member_init)
3727 << SourceRange(IdLoc, Init->getSourceRange().getEnd());
3729 return BuildMemberInitializer(Member, Init, IdLoc);
3733 // It didn't name a member, so see if it names a class.
3735 TypeSourceInfo *TInfo = nullptr;
3737 if (TemplateTypeTy) {
3738 BaseType = GetTypeFromParser(TemplateTypeTy, &TInfo);
3739 } else if (DS.getTypeSpecType() == TST_decltype) {
3740 BaseType = BuildDecltypeType(DS.getRepAsExpr(), DS.getTypeSpecTypeLoc());
3741 } else if (DS.getTypeSpecType() == TST_decltype_auto) {
3742 Diag(DS.getTypeSpecTypeLoc(), diag::err_decltype_auto_invalid);
3745 LookupResult R(*this, MemberOrBase, IdLoc, LookupOrdinaryName);
3746 LookupParsedName(R, S, &SS);
3748 TypeDecl *TyD = R.getAsSingle<TypeDecl>();
3750 if (R.isAmbiguous()) return true;
3752 // We don't want access-control diagnostics here.
3753 R.suppressDiagnostics();
3755 if (SS.isSet() && isDependentScopeSpecifier(SS)) {
3756 bool NotUnknownSpecialization = false;
3757 DeclContext *DC = computeDeclContext(SS, false);
3758 if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(DC))
3759 NotUnknownSpecialization = !Record->hasAnyDependentBases();
3761 if (!NotUnknownSpecialization) {
3762 // When the scope specifier can refer to a member of an unknown
3763 // specialization, we take it as a type name.
3764 BaseType = CheckTypenameType(ETK_None, SourceLocation(),
3765 SS.getWithLocInContext(Context),
3766 *MemberOrBase, IdLoc);
3767 if (BaseType.isNull())
3771 R.setLookupName(MemberOrBase);
3775 // If no results were found, try to correct typos.
3776 TypoCorrection Corr;
3777 if (R.empty() && BaseType.isNull() &&
3778 (Corr = CorrectTypo(
3779 R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
3780 llvm::make_unique<MemInitializerValidatorCCC>(ClassDecl),
3781 CTK_ErrorRecovery, ClassDecl))) {
3782 if (FieldDecl *Member = Corr.getCorrectionDeclAs<FieldDecl>()) {
3783 // We have found a non-static data member with a similar
3784 // name to what was typed; complain and initialize that
3787 PDiag(diag::err_mem_init_not_member_or_class_suggest)
3788 << MemberOrBase << true);
3789 return BuildMemberInitializer(Member, Init, IdLoc);
3790 } else if (TypeDecl *Type = Corr.getCorrectionDeclAs<TypeDecl>()) {
3791 const CXXBaseSpecifier *DirectBaseSpec;
3792 const CXXBaseSpecifier *VirtualBaseSpec;
3793 if (FindBaseInitializer(*this, ClassDecl,
3794 Context.getTypeDeclType(Type),
3795 DirectBaseSpec, VirtualBaseSpec)) {
3796 // We have found a direct or virtual base class with a
3797 // similar name to what was typed; complain and initialize
3800 PDiag(diag::err_mem_init_not_member_or_class_suggest)
3801 << MemberOrBase << false,
3802 PDiag() /*Suppress note, we provide our own.*/);
3804 const CXXBaseSpecifier *BaseSpec = DirectBaseSpec ? DirectBaseSpec
3806 Diag(BaseSpec->getLocStart(),
3807 diag::note_base_class_specified_here)
3808 << BaseSpec->getType()
3809 << BaseSpec->getSourceRange();
3816 if (!TyD && BaseType.isNull()) {
3817 Diag(IdLoc, diag::err_mem_init_not_member_or_class)
3818 << MemberOrBase << SourceRange(IdLoc,Init->getSourceRange().getEnd());
3823 if (BaseType.isNull()) {
3824 BaseType = Context.getTypeDeclType(TyD);
3825 MarkAnyDeclReferenced(TyD->getLocation(), TyD, /*OdrUse=*/false);
3827 BaseType = Context.getElaboratedType(ETK_None, SS.getScopeRep(),
3829 TInfo = Context.CreateTypeSourceInfo(BaseType);
3830 ElaboratedTypeLoc TL = TInfo->getTypeLoc().castAs<ElaboratedTypeLoc>();
3831 TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(IdLoc);
3832 TL.setElaboratedKeywordLoc(SourceLocation());
3833 TL.setQualifierLoc(SS.getWithLocInContext(Context));
3839 TInfo = Context.getTrivialTypeSourceInfo(BaseType, IdLoc);
3841 return BuildBaseInitializer(BaseType, TInfo, Init, ClassDecl, EllipsisLoc);
3844 /// Checks a member initializer expression for cases where reference (or
3845 /// pointer) members are bound to by-value parameters (or their addresses).
3846 static void CheckForDanglingReferenceOrPointer(Sema &S, ValueDecl *Member,
3848 SourceLocation IdLoc) {
3849 QualType MemberTy = Member->getType();
3851 // We only handle pointers and references currently.
3852 // FIXME: Would this be relevant for ObjC object pointers? Or block pointers?
3853 if (!MemberTy->isReferenceType() && !MemberTy->isPointerType())
3856 const bool IsPointer = MemberTy->isPointerType();
3858 if (const UnaryOperator *Op
3859 = dyn_cast<UnaryOperator>(Init->IgnoreParenImpCasts())) {
3860 // The only case we're worried about with pointers requires taking the
3862 if (Op->getOpcode() != UO_AddrOf)
3865 Init = Op->getSubExpr();
3867 // We only handle address-of expression initializers for pointers.
3872 if (const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(Init->IgnoreParens())) {
3873 // We only warn when referring to a non-reference parameter declaration.
3874 const ParmVarDecl *Parameter = dyn_cast<ParmVarDecl>(DRE->getDecl());
3875 if (!Parameter || Parameter->getType()->isReferenceType())
3878 S.Diag(Init->getExprLoc(),
3879 IsPointer ? diag::warn_init_ptr_member_to_parameter_addr
3880 : diag::warn_bind_ref_member_to_parameter)
3881 << Member << Parameter << Init->getSourceRange();
3883 // Other initializers are fine.
3887 S.Diag(Member->getLocation(), diag::note_ref_or_ptr_member_declared_here)
3888 << (unsigned)IsPointer;
3892 Sema::BuildMemberInitializer(ValueDecl *Member, Expr *Init,
3893 SourceLocation IdLoc) {
3894 FieldDecl *DirectMember = dyn_cast<FieldDecl>(Member);
3895 IndirectFieldDecl *IndirectMember = dyn_cast<IndirectFieldDecl>(Member);
3896 assert((DirectMember || IndirectMember) &&
3897 "Member must be a FieldDecl or IndirectFieldDecl");
3899 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
3902 if (Member->isInvalidDecl())
3906 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
3907 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
3908 } else if (InitListExpr *InitList = dyn_cast<InitListExpr>(Init)) {
3909 Args = MultiExprArg(InitList->getInits(), InitList->getNumInits());
3911 // Template instantiation doesn't reconstruct ParenListExprs for us.
3915 SourceRange InitRange = Init->getSourceRange();
3917 if (Member->getType()->isDependentType() || Init->isTypeDependent()) {
3918 // Can't check initialization for a member of dependent type or when
3919 // any of the arguments are type-dependent expressions.
3920 DiscardCleanupsInEvaluationContext();
3922 bool InitList = false;
3923 if (isa<InitListExpr>(Init)) {
3928 // Initialize the member.
3929 InitializedEntity MemberEntity =
3930 DirectMember ? InitializedEntity::InitializeMember(DirectMember, nullptr)
3931 : InitializedEntity::InitializeMember(IndirectMember,
3933 InitializationKind Kind =
3934 InitList ? InitializationKind::CreateDirectList(IdLoc)
3935 : InitializationKind::CreateDirect(IdLoc, InitRange.getBegin(),
3936 InitRange.getEnd());
3938 InitializationSequence InitSeq(*this, MemberEntity, Kind, Args);
3939 ExprResult MemberInit = InitSeq.Perform(*this, MemberEntity, Kind, Args,
3941 if (MemberInit.isInvalid())
3944 CheckForDanglingReferenceOrPointer(*this, Member, MemberInit.get(), IdLoc);
3946 // C++11 [class.base.init]p7:
3947 // The initialization of each base and member constitutes a
3949 MemberInit = ActOnFinishFullExpr(MemberInit.get(), InitRange.getBegin());
3950 if (MemberInit.isInvalid())
3953 Init = MemberInit.get();
3957 return new (Context) CXXCtorInitializer(Context, DirectMember, IdLoc,
3958 InitRange.getBegin(), Init,
3959 InitRange.getEnd());
3961 return new (Context) CXXCtorInitializer(Context, IndirectMember, IdLoc,
3962 InitRange.getBegin(), Init,
3963 InitRange.getEnd());
3968 Sema::BuildDelegatingInitializer(TypeSourceInfo *TInfo, Expr *Init,
3969 CXXRecordDecl *ClassDecl) {
3970 SourceLocation NameLoc = TInfo->getTypeLoc().getLocalSourceRange().getBegin();
3971 if (!LangOpts.CPlusPlus11)
3972 return Diag(NameLoc, diag::err_delegating_ctor)
3973 << TInfo->getTypeLoc().getLocalSourceRange();
3974 Diag(NameLoc, diag::warn_cxx98_compat_delegating_ctor);
3976 bool InitList = true;
3977 MultiExprArg Args = Init;
3978 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
3980 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
3983 SourceRange InitRange = Init->getSourceRange();
3984 // Initialize the object.
3985 InitializedEntity DelegationEntity = InitializedEntity::InitializeDelegation(
3986 QualType(ClassDecl->getTypeForDecl(), 0));
3987 InitializationKind Kind =
3988 InitList ? InitializationKind::CreateDirectList(NameLoc)
3989 : InitializationKind::CreateDirect(NameLoc, InitRange.getBegin(),
3990 InitRange.getEnd());
3991 InitializationSequence InitSeq(*this, DelegationEntity, Kind, Args);
3992 ExprResult DelegationInit = InitSeq.Perform(*this, DelegationEntity, Kind,
3994 if (DelegationInit.isInvalid())
3997 assert(cast<CXXConstructExpr>(DelegationInit.get())->getConstructor() &&
3998 "Delegating constructor with no target?");
4000 // C++11 [class.base.init]p7:
4001 // The initialization of each base and member constitutes a
4003 DelegationInit = ActOnFinishFullExpr(DelegationInit.get(),
4004 InitRange.getBegin());
4005 if (DelegationInit.isInvalid())
4008 // If we are in a dependent context, template instantiation will
4009 // perform this type-checking again. Just save the arguments that we
4010 // received in a ParenListExpr.
4011 // FIXME: This isn't quite ideal, since our ASTs don't capture all
4012 // of the information that we have about the base
4013 // initializer. However, deconstructing the ASTs is a dicey process,
4014 // and this approach is far more likely to get the corner cases right.
4015 if (CurContext->isDependentContext())
4016 DelegationInit = Init;
4018 return new (Context) CXXCtorInitializer(Context, TInfo, InitRange.getBegin(),
4019 DelegationInit.getAs<Expr>(),
4020 InitRange.getEnd());
4024 Sema::BuildBaseInitializer(QualType BaseType, TypeSourceInfo *BaseTInfo,
4025 Expr *Init, CXXRecordDecl *ClassDecl,
4026 SourceLocation EllipsisLoc) {
4027 SourceLocation BaseLoc
4028 = BaseTInfo->getTypeLoc().getLocalSourceRange().getBegin();
4030 if (!BaseType->isDependentType() && !BaseType->isRecordType())
4031 return Diag(BaseLoc, diag::err_base_init_does_not_name_class)
4032 << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
4034 // C++ [class.base.init]p2:
4035 // [...] Unless the mem-initializer-id names a nonstatic data
4036 // member of the constructor's class or a direct or virtual base
4037 // of that class, the mem-initializer is ill-formed. A
4038 // mem-initializer-list can initialize a base class using any
4039 // name that denotes that base class type.
4040 bool Dependent = BaseType->isDependentType() || Init->isTypeDependent();
4042 SourceRange InitRange = Init->getSourceRange();
4043 if (EllipsisLoc.isValid()) {
4044 // This is a pack expansion.
4045 if (!BaseType->containsUnexpandedParameterPack()) {
4046 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
4047 << SourceRange(BaseLoc, InitRange.getEnd());
4049 EllipsisLoc = SourceLocation();
4052 // Check for any unexpanded parameter packs.
4053 if (DiagnoseUnexpandedParameterPack(BaseLoc, BaseTInfo, UPPC_Initializer))
4056 if (DiagnoseUnexpandedParameterPack(Init, UPPC_Initializer))
4060 // Check for direct and virtual base classes.
4061 const CXXBaseSpecifier *DirectBaseSpec = nullptr;
4062 const CXXBaseSpecifier *VirtualBaseSpec = nullptr;
4064 if (Context.hasSameUnqualifiedType(QualType(ClassDecl->getTypeForDecl(),0),
4066 return BuildDelegatingInitializer(BaseTInfo, Init, ClassDecl);
4068 FindBaseInitializer(*this, ClassDecl, BaseType, DirectBaseSpec,
4071 // C++ [base.class.init]p2:
4072 // Unless the mem-initializer-id names a nonstatic data member of the
4073 // constructor's class or a direct or virtual base of that class, the
4074 // mem-initializer is ill-formed.
4075 if (!DirectBaseSpec && !VirtualBaseSpec) {
4076 // If the class has any dependent bases, then it's possible that
4077 // one of those types will resolve to the same type as
4078 // BaseType. Therefore, just treat this as a dependent base
4079 // class initialization. FIXME: Should we try to check the
4080 // initialization anyway? It seems odd.
4081 if (ClassDecl->hasAnyDependentBases())
4084 return Diag(BaseLoc, diag::err_not_direct_base_or_virtual)
4085 << BaseType << Context.getTypeDeclType(ClassDecl)
4086 << BaseTInfo->getTypeLoc().getLocalSourceRange();
4091 DiscardCleanupsInEvaluationContext();
4093 return new (Context) CXXCtorInitializer(Context, BaseTInfo,
4094 /*IsVirtual=*/false,
4095 InitRange.getBegin(), Init,
4096 InitRange.getEnd(), EllipsisLoc);
4099 // C++ [base.class.init]p2:
4100 // If a mem-initializer-id is ambiguous because it designates both
4101 // a direct non-virtual base class and an inherited virtual base
4102 // class, the mem-initializer is ill-formed.
4103 if (DirectBaseSpec && VirtualBaseSpec)
4104 return Diag(BaseLoc, diag::err_base_init_direct_and_virtual)
4105 << BaseType << BaseTInfo->getTypeLoc().getLocalSourceRange();
4107 const CXXBaseSpecifier *BaseSpec = DirectBaseSpec;
4109 BaseSpec = VirtualBaseSpec;
4111 // Initialize the base.
4112 bool InitList = true;
4113 MultiExprArg Args = Init;
4114 if (ParenListExpr *ParenList = dyn_cast<ParenListExpr>(Init)) {
4116 Args = MultiExprArg(ParenList->getExprs(), ParenList->getNumExprs());
4119 InitializedEntity BaseEntity =
4120 InitializedEntity::InitializeBase(Context, BaseSpec, VirtualBaseSpec);
4121 InitializationKind Kind =
4122 InitList ? InitializationKind::CreateDirectList(BaseLoc)
4123 : InitializationKind::CreateDirect(BaseLoc, InitRange.getBegin(),
4124 InitRange.getEnd());
4125 InitializationSequence InitSeq(*this, BaseEntity, Kind, Args);
4126 ExprResult BaseInit = InitSeq.Perform(*this, BaseEntity, Kind, Args, nullptr);
4127 if (BaseInit.isInvalid())
4130 // C++11 [class.base.init]p7:
4131 // The initialization of each base and member constitutes a
4133 BaseInit = ActOnFinishFullExpr(BaseInit.get(), InitRange.getBegin());
4134 if (BaseInit.isInvalid())
4137 // If we are in a dependent context, template instantiation will
4138 // perform this type-checking again. Just save the arguments that we
4139 // received in a ParenListExpr.
4140 // FIXME: This isn't quite ideal, since our ASTs don't capture all
4141 // of the information that we have about the base
4142 // initializer. However, deconstructing the ASTs is a dicey process,
4143 // and this approach is far more likely to get the corner cases right.
4144 if (CurContext->isDependentContext())
4147 return new (Context) CXXCtorInitializer(Context, BaseTInfo,
4148 BaseSpec->isVirtual(),
4149 InitRange.getBegin(),
4150 BaseInit.getAs<Expr>(),
4151 InitRange.getEnd(), EllipsisLoc);
4154 // Create a static_cast\<T&&>(expr).
4155 static Expr *CastForMoving(Sema &SemaRef, Expr *E, QualType T = QualType()) {
4156 if (T.isNull()) T = E->getType();
4157 QualType TargetType = SemaRef.BuildReferenceType(
4158 T, /*SpelledAsLValue*/false, SourceLocation(), DeclarationName());
4159 SourceLocation ExprLoc = E->getLocStart();
4160 TypeSourceInfo *TargetLoc = SemaRef.Context.getTrivialTypeSourceInfo(
4161 TargetType, ExprLoc);
4163 return SemaRef.BuildCXXNamedCast(ExprLoc, tok::kw_static_cast, TargetLoc, E,
4164 SourceRange(ExprLoc, ExprLoc),
4165 E->getSourceRange()).get();
4168 /// ImplicitInitializerKind - How an implicit base or member initializer should
4169 /// initialize its base or member.
4170 enum ImplicitInitializerKind {
4178 BuildImplicitBaseInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
4179 ImplicitInitializerKind ImplicitInitKind,
4180 CXXBaseSpecifier *BaseSpec,
4181 bool IsInheritedVirtualBase,
4182 CXXCtorInitializer *&CXXBaseInit) {
4183 InitializedEntity InitEntity
4184 = InitializedEntity::InitializeBase(SemaRef.Context, BaseSpec,
4185 IsInheritedVirtualBase);
4187 ExprResult BaseInit;
4189 switch (ImplicitInitKind) {
4192 InitializationKind InitKind
4193 = InitializationKind::CreateDefault(Constructor->getLocation());
4194 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
4195 BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
4201 bool Moving = ImplicitInitKind == IIK_Move;
4202 ParmVarDecl *Param = Constructor->getParamDecl(0);
4203 QualType ParamType = Param->getType().getNonReferenceType();
4206 DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
4207 SourceLocation(), Param, false,
4208 Constructor->getLocation(), ParamType,
4209 VK_LValue, nullptr);
4211 SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(CopyCtorArg));
4213 // Cast to the base class to avoid ambiguities.
4215 SemaRef.Context.getQualifiedType(BaseSpec->getType().getUnqualifiedType(),
4216 ParamType.getQualifiers());
4219 CopyCtorArg = CastForMoving(SemaRef, CopyCtorArg);
4222 CXXCastPath BasePath;
4223 BasePath.push_back(BaseSpec);
4224 CopyCtorArg = SemaRef.ImpCastExprToType(CopyCtorArg, ArgTy,
4225 CK_UncheckedDerivedToBase,
4226 Moving ? VK_XValue : VK_LValue,
4229 InitializationKind InitKind
4230 = InitializationKind::CreateDirect(Constructor->getLocation(),
4231 SourceLocation(), SourceLocation());
4232 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, CopyCtorArg);
4233 BaseInit = InitSeq.Perform(SemaRef, InitEntity, InitKind, CopyCtorArg);
4238 BaseInit = SemaRef.MaybeCreateExprWithCleanups(BaseInit);
4239 if (BaseInit.isInvalid())
4243 new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4244 SemaRef.Context.getTrivialTypeSourceInfo(BaseSpec->getType(),
4246 BaseSpec->isVirtual(),
4248 BaseInit.getAs<Expr>(),
4255 static bool RefersToRValueRef(Expr *MemRef) {
4256 ValueDecl *Referenced = cast<MemberExpr>(MemRef)->getMemberDecl();
4257 return Referenced->getType()->isRValueReferenceType();
4261 BuildImplicitMemberInitializer(Sema &SemaRef, CXXConstructorDecl *Constructor,
4262 ImplicitInitializerKind ImplicitInitKind,
4263 FieldDecl *Field, IndirectFieldDecl *Indirect,
4264 CXXCtorInitializer *&CXXMemberInit) {
4265 if (Field->isInvalidDecl())
4268 SourceLocation Loc = Constructor->getLocation();
4270 if (ImplicitInitKind == IIK_Copy || ImplicitInitKind == IIK_Move) {
4271 bool Moving = ImplicitInitKind == IIK_Move;
4272 ParmVarDecl *Param = Constructor->getParamDecl(0);
4273 QualType ParamType = Param->getType().getNonReferenceType();
4275 // Suppress copying zero-width bitfields.
4276 if (Field->isBitField() && Field->getBitWidthValue(SemaRef.Context) == 0)
4279 Expr *MemberExprBase =
4280 DeclRefExpr::Create(SemaRef.Context, NestedNameSpecifierLoc(),
4281 SourceLocation(), Param, false,
4282 Loc, ParamType, VK_LValue, nullptr);
4284 SemaRef.MarkDeclRefReferenced(cast<DeclRefExpr>(MemberExprBase));
4287 MemberExprBase = CastForMoving(SemaRef, MemberExprBase);
4290 // Build a reference to this field within the parameter.
4292 LookupResult MemberLookup(SemaRef, Field->getDeclName(), Loc,
4293 Sema::LookupMemberName);
4294 MemberLookup.addDecl(Indirect ? cast<ValueDecl>(Indirect)
4295 : cast<ValueDecl>(Field), AS_public);
4296 MemberLookup.resolveKind();
4298 = SemaRef.BuildMemberReferenceExpr(MemberExprBase,
4302 /*TemplateKWLoc=*/SourceLocation(),
4303 /*FirstQualifierInScope=*/nullptr,
4305 /*TemplateArgs=*/nullptr,
4307 if (CtorArg.isInvalid())
4310 // C++11 [class.copy]p15:
4311 // - if a member m has rvalue reference type T&&, it is direct-initialized
4312 // with static_cast<T&&>(x.m);
4313 if (RefersToRValueRef(CtorArg.get())) {
4314 CtorArg = CastForMoving(SemaRef, CtorArg.get());
4317 InitializedEntity Entity =
4318 Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
4320 : InitializedEntity::InitializeMember(Field, nullptr,
4323 // Direct-initialize to use the copy constructor.
4324 InitializationKind InitKind =
4325 InitializationKind::CreateDirect(Loc, SourceLocation(), SourceLocation());
4327 Expr *CtorArgE = CtorArg.getAs<Expr>();
4328 InitializationSequence InitSeq(SemaRef, Entity, InitKind, CtorArgE);
4329 ExprResult MemberInit =
4330 InitSeq.Perform(SemaRef, Entity, InitKind, MultiExprArg(&CtorArgE, 1));
4331 MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
4332 if (MemberInit.isInvalid())
4336 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
4337 SemaRef.Context, Indirect, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
4339 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(
4340 SemaRef.Context, Field, Loc, Loc, MemberInit.getAs<Expr>(), Loc);
4344 assert((ImplicitInitKind == IIK_Default || ImplicitInitKind == IIK_Inherit) &&
4345 "Unhandled implicit init kind!");
4347 QualType FieldBaseElementType =
4348 SemaRef.Context.getBaseElementType(Field->getType());
4350 if (FieldBaseElementType->isRecordType()) {
4351 InitializedEntity InitEntity =
4352 Indirect ? InitializedEntity::InitializeMember(Indirect, nullptr,
4354 : InitializedEntity::InitializeMember(Field, nullptr,
4356 InitializationKind InitKind =
4357 InitializationKind::CreateDefault(Loc);
4359 InitializationSequence InitSeq(SemaRef, InitEntity, InitKind, None);
4360 ExprResult MemberInit =
4361 InitSeq.Perform(SemaRef, InitEntity, InitKind, None);
4363 MemberInit = SemaRef.MaybeCreateExprWithCleanups(MemberInit);
4364 if (MemberInit.isInvalid())
4368 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4374 CXXMemberInit = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context,
4381 if (!Field->getParent()->isUnion()) {
4382 if (FieldBaseElementType->isReferenceType()) {
4383 SemaRef.Diag(Constructor->getLocation(),
4384 diag::err_uninitialized_member_in_ctor)
4385 << (int)Constructor->isImplicit()
4386 << SemaRef.Context.getTagDeclType(Constructor->getParent())
4387 << 0 << Field->getDeclName();
4388 SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
4392 if (FieldBaseElementType.isConstQualified()) {
4393 SemaRef.Diag(Constructor->getLocation(),
4394 diag::err_uninitialized_member_in_ctor)
4395 << (int)Constructor->isImplicit()
4396 << SemaRef.Context.getTagDeclType(Constructor->getParent())
4397 << 1 << Field->getDeclName();
4398 SemaRef.Diag(Field->getLocation(), diag::note_declared_at);
4403 if (FieldBaseElementType.hasNonTrivialObjCLifetime()) {
4405 // Default-initialize Objective-C pointers to NULL.
4407 = new (SemaRef.Context) CXXCtorInitializer(SemaRef.Context, Field,
4409 new (SemaRef.Context) ImplicitValueInitExpr(Field->getType()),
4414 // Nothing to initialize.
4415 CXXMemberInit = nullptr;
4420 struct BaseAndFieldInfo {
4422 CXXConstructorDecl *Ctor;
4423 bool AnyErrorsInInits;
4424 ImplicitInitializerKind IIK;
4425 llvm::DenseMap<const void *, CXXCtorInitializer*> AllBaseFields;
4426 SmallVector<CXXCtorInitializer*, 8> AllToInit;
4427 llvm::DenseMap<TagDecl*, FieldDecl*> ActiveUnionMember;
4429 BaseAndFieldInfo(Sema &S, CXXConstructorDecl *Ctor, bool ErrorsInInits)
4430 : S(S), Ctor(Ctor), AnyErrorsInInits(ErrorsInInits) {
4431 bool Generated = Ctor->isImplicit() || Ctor->isDefaulted();
4432 if (Ctor->getInheritedConstructor())
4434 else if (Generated && Ctor->isCopyConstructor())
4436 else if (Generated && Ctor->isMoveConstructor())
4442 bool isImplicitCopyOrMove() const {
4453 llvm_unreachable("Invalid ImplicitInitializerKind!");
4456 bool addFieldInitializer(CXXCtorInitializer *Init) {
4457 AllToInit.push_back(Init);
4459 // Check whether this initializer makes the field "used".
4460 if (Init->getInit()->HasSideEffects(S.Context))
4461 S.UnusedPrivateFields.remove(Init->getAnyMember());
4466 bool isInactiveUnionMember(FieldDecl *Field) {
4467 RecordDecl *Record = Field->getParent();
4468 if (!Record->isUnion())
4471 if (FieldDecl *Active =
4472 ActiveUnionMember.lookup(Record->getCanonicalDecl()))
4473 return Active != Field->getCanonicalDecl();
4475 // In an implicit copy or move constructor, ignore any in-class initializer.
4476 if (isImplicitCopyOrMove())
4479 // If there's no explicit initialization, the field is active only if it
4480 // has an in-class initializer...
4481 if (Field->hasInClassInitializer())
4483 // ... or it's an anonymous struct or union whose class has an in-class
4485 if (!Field->isAnonymousStructOrUnion())
4487 CXXRecordDecl *FieldRD = Field->getType()->getAsCXXRecordDecl();
4488 return !FieldRD->hasInClassInitializer();
4491 /// \brief Determine whether the given field is, or is within, a union member
4492 /// that is inactive (because there was an initializer given for a different
4493 /// member of the union, or because the union was not initialized at all).
4494 bool isWithinInactiveUnionMember(FieldDecl *Field,
4495 IndirectFieldDecl *Indirect) {
4497 return isInactiveUnionMember(Field);
4499 for (auto *C : Indirect->chain()) {
4500 FieldDecl *Field = dyn_cast<FieldDecl>(C);
4501 if (Field && isInactiveUnionMember(Field))
4509 /// \brief Determine whether the given type is an incomplete or zero-lenfgth
4511 static bool isIncompleteOrZeroLengthArrayType(ASTContext &Context, QualType T) {
4512 if (T->isIncompleteArrayType())
4515 while (const ConstantArrayType *ArrayT = Context.getAsConstantArrayType(T)) {
4516 if (!ArrayT->getSize())
4519 T = ArrayT->getElementType();
4525 static bool CollectFieldInitializer(Sema &SemaRef, BaseAndFieldInfo &Info,
4527 IndirectFieldDecl *Indirect = nullptr) {
4528 if (Field->isInvalidDecl())
4531 // Overwhelmingly common case: we have a direct initializer for this field.
4532 if (CXXCtorInitializer *Init =
4533 Info.AllBaseFields.lookup(Field->getCanonicalDecl()))
4534 return Info.addFieldInitializer(Init);
4536 // C++11 [class.base.init]p8:
4537 // if the entity is a non-static data member that has a
4538 // brace-or-equal-initializer and either
4539 // -- the constructor's class is a union and no other variant member of that
4540 // union is designated by a mem-initializer-id or
4541 // -- the constructor's class is not a union, and, if the entity is a member
4542 // of an anonymous union, no other member of that union is designated by
4543 // a mem-initializer-id,
4544 // the entity is initialized as specified in [dcl.init].
4546 // We also apply the same rules to handle anonymous structs within anonymous
4548 if (Info.isWithinInactiveUnionMember(Field, Indirect))
4551 if (Field->hasInClassInitializer() && !Info.isImplicitCopyOrMove()) {
4553 SemaRef.BuildCXXDefaultInitExpr(Info.Ctor->getLocation(), Field);
4554 if (DIE.isInvalid())
4556 CXXCtorInitializer *Init;
4558 Init = new (SemaRef.Context)
4559 CXXCtorInitializer(SemaRef.Context, Indirect, SourceLocation(),
4560 SourceLocation(), DIE.get(), SourceLocation());
4562 Init = new (SemaRef.Context)
4563 CXXCtorInitializer(SemaRef.Context, Field, SourceLocation(),
4564 SourceLocation(), DIE.get(), SourceLocation());
4565 return Info.addFieldInitializer(Init);
4568 // Don't initialize incomplete or zero-length arrays.
4569 if (isIncompleteOrZeroLengthArrayType(SemaRef.Context, Field->getType()))
4572 // Don't try to build an implicit initializer if there were semantic
4573 // errors in any of the initializers (and therefore we might be
4574 // missing some that the user actually wrote).
4575 if (Info.AnyErrorsInInits)
4578 CXXCtorInitializer *Init = nullptr;
4579 if (BuildImplicitMemberInitializer(Info.S, Info.Ctor, Info.IIK, Field,
4586 return Info.addFieldInitializer(Init);
4590 Sema::SetDelegatingInitializer(CXXConstructorDecl *Constructor,
4591 CXXCtorInitializer *Initializer) {
4592 assert(Initializer->isDelegatingInitializer());
4593 Constructor->setNumCtorInitializers(1);
4594 CXXCtorInitializer **initializer =
4595 new (Context) CXXCtorInitializer*[1];
4596 memcpy(initializer, &Initializer, sizeof (CXXCtorInitializer*));
4597 Constructor->setCtorInitializers(initializer);
4599 if (CXXDestructorDecl *Dtor = LookupDestructor(Constructor->getParent())) {
4600 MarkFunctionReferenced(Initializer->getSourceLocation(), Dtor);
4601 DiagnoseUseOfDecl(Dtor, Initializer->getSourceLocation());
4604 DelegatingCtorDecls.push_back(Constructor);
4606 DiagnoseUninitializedFields(*this, Constructor);
4611 bool Sema::SetCtorInitializers(CXXConstructorDecl *Constructor, bool AnyErrors,
4612 ArrayRef<CXXCtorInitializer *> Initializers) {
4613 if (Constructor->isDependentContext()) {
4614 // Just store the initializers as written, they will be checked during
4616 if (!Initializers.empty()) {
4617 Constructor->setNumCtorInitializers(Initializers.size());
4618 CXXCtorInitializer **baseOrMemberInitializers =
4619 new (Context) CXXCtorInitializer*[Initializers.size()];
4620 memcpy(baseOrMemberInitializers, Initializers.data(),
4621 Initializers.size() * sizeof(CXXCtorInitializer*));
4622 Constructor->setCtorInitializers(baseOrMemberInitializers);
4625 // Let template instantiation know whether we had errors.
4627 Constructor->setInvalidDecl();
4632 BaseAndFieldInfo Info(*this, Constructor, AnyErrors);
4634 // We need to build the initializer AST according to order of construction
4635 // and not what user specified in the Initializers list.
4636 CXXRecordDecl *ClassDecl = Constructor->getParent()->getDefinition();
4640 bool HadError = false;
4642 for (unsigned i = 0; i < Initializers.size(); i++) {
4643 CXXCtorInitializer *Member = Initializers[i];
4645 if (Member->isBaseInitializer())
4646 Info.AllBaseFields[Member->getBaseClass()->getAs<RecordType>()] = Member;
4648 Info.AllBaseFields[Member->getAnyMember()->getCanonicalDecl()] = Member;
4650 if (IndirectFieldDecl *F = Member->getIndirectMember()) {
4651 for (auto *C : F->chain()) {
4652 FieldDecl *FD = dyn_cast<FieldDecl>(C);
4653 if (FD && FD->getParent()->isUnion())
4654 Info.ActiveUnionMember.insert(std::make_pair(
4655 FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
4657 } else if (FieldDecl *FD = Member->getMember()) {
4658 if (FD->getParent()->isUnion())
4659 Info.ActiveUnionMember.insert(std::make_pair(
4660 FD->getParent()->getCanonicalDecl(), FD->getCanonicalDecl()));
4665 // Keep track of the direct virtual bases.
4666 llvm::SmallPtrSet<CXXBaseSpecifier *, 16> DirectVBases;
4667 for (auto &I : ClassDecl->bases()) {
4669 DirectVBases.insert(&I);
4672 // Push virtual bases before others.
4673 for (auto &VBase : ClassDecl->vbases()) {
4674 if (CXXCtorInitializer *Value
4675 = Info.AllBaseFields.lookup(VBase.getType()->getAs<RecordType>())) {
4676 // [class.base.init]p7, per DR257:
4677 // A mem-initializer where the mem-initializer-id names a virtual base
4678 // class is ignored during execution of a constructor of any class that
4679 // is not the most derived class.
4680 if (ClassDecl->isAbstract()) {
4681 // FIXME: Provide a fixit to remove the base specifier. This requires
4682 // tracking the location of the associated comma for a base specifier.
4683 Diag(Value->getSourceLocation(), diag::warn_abstract_vbase_init_ignored)
4684 << VBase.getType() << ClassDecl;
4685 DiagnoseAbstractType(ClassDecl);
4688 Info.AllToInit.push_back(Value);
4689 } else if (!AnyErrors && !ClassDecl->isAbstract()) {
4690 // [class.base.init]p8, per DR257:
4691 // If a given [...] base class is not named by a mem-initializer-id
4692 // [...] and the entity is not a virtual base class of an abstract
4693 // class, then [...] the entity is default-initialized.
4694 bool IsInheritedVirtualBase = !DirectVBases.count(&VBase);
4695 CXXCtorInitializer *CXXBaseInit;
4696 if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
4697 &VBase, IsInheritedVirtualBase,
4703 Info.AllToInit.push_back(CXXBaseInit);
4707 // Non-virtual bases.
4708 for (auto &Base : ClassDecl->bases()) {
4709 // Virtuals are in the virtual base list and already constructed.
4710 if (Base.isVirtual())
4713 if (CXXCtorInitializer *Value
4714 = Info.AllBaseFields.lookup(Base.getType()->getAs<RecordType>())) {
4715 Info.AllToInit.push_back(Value);
4716 } else if (!AnyErrors) {
4717 CXXCtorInitializer *CXXBaseInit;
4718 if (BuildImplicitBaseInitializer(*this, Constructor, Info.IIK,
4719 &Base, /*IsInheritedVirtualBase=*/false,
4725 Info.AllToInit.push_back(CXXBaseInit);
4730 for (auto *Mem : ClassDecl->decls()) {
4731 if (auto *F = dyn_cast<FieldDecl>(Mem)) {
4732 // C++ [class.bit]p2:
4733 // A declaration for a bit-field that omits the identifier declares an
4734 // unnamed bit-field. Unnamed bit-fields are not members and cannot be
4736 if (F->isUnnamedBitfield())
4739 // If we're not generating the implicit copy/move constructor, then we'll
4740 // handle anonymous struct/union fields based on their individual
4742 if (F->isAnonymousStructOrUnion() && !Info.isImplicitCopyOrMove())
4745 if (CollectFieldInitializer(*this, Info, F))
4750 // Beyond this point, we only consider default initialization.
4751 if (Info.isImplicitCopyOrMove())
4754 if (auto *F = dyn_cast<IndirectFieldDecl>(Mem)) {
4755 if (F->getType()->isIncompleteArrayType()) {
4756 assert(ClassDecl->hasFlexibleArrayMember() &&
4757 "Incomplete array type is not valid");
4761 // Initialize each field of an anonymous struct individually.
4762 if (CollectFieldInitializer(*this, Info, F->getAnonField(), F))
4769 unsigned NumInitializers = Info.AllToInit.size();
4770 if (NumInitializers > 0) {
4771 Constructor->setNumCtorInitializers(NumInitializers);
4772 CXXCtorInitializer **baseOrMemberInitializers =
4773 new (Context) CXXCtorInitializer*[NumInitializers];
4774 memcpy(baseOrMemberInitializers, Info.AllToInit.data(),
4775 NumInitializers * sizeof(CXXCtorInitializer*));
4776 Constructor->setCtorInitializers(baseOrMemberInitializers);
4778 // Constructors implicitly reference the base and member
4780 MarkBaseAndMemberDestructorsReferenced(Constructor->getLocation(),
4781 Constructor->getParent());
4787 static void PopulateKeysForFields(FieldDecl *Field, SmallVectorImpl<const void*> &IdealInits) {
4788 if (const RecordType *RT = Field->getType()->getAs<RecordType>()) {
4789 const RecordDecl *RD = RT->getDecl();
4790 if (RD->isAnonymousStructOrUnion()) {
4791 for (auto *Field : RD->fields())
4792 PopulateKeysForFields(Field, IdealInits);
4796 IdealInits.push_back(Field->getCanonicalDecl());
4799 static const void *GetKeyForBase(ASTContext &Context, QualType BaseType) {
4800 return Context.getCanonicalType(BaseType).getTypePtr();
4803 static const void *GetKeyForMember(ASTContext &Context,
4804 CXXCtorInitializer *Member) {
4805 if (!Member->isAnyMemberInitializer())
4806 return GetKeyForBase(Context, QualType(Member->getBaseClass(), 0));
4808 return Member->getAnyMember()->getCanonicalDecl();
4811 static void DiagnoseBaseOrMemInitializerOrder(
4812 Sema &SemaRef, const CXXConstructorDecl *Constructor,
4813 ArrayRef<CXXCtorInitializer *> Inits) {
4814 if (Constructor->getDeclContext()->isDependentContext())
4817 // Don't check initializers order unless the warning is enabled at the
4818 // location of at least one initializer.
4819 bool ShouldCheckOrder = false;
4820 for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
4821 CXXCtorInitializer *Init = Inits[InitIndex];
4822 if (!SemaRef.Diags.isIgnored(diag::warn_initializer_out_of_order,
4823 Init->getSourceLocation())) {
4824 ShouldCheckOrder = true;
4828 if (!ShouldCheckOrder)
4831 // Build the list of bases and members in the order that they'll
4832 // actually be initialized. The explicit initializers should be in
4833 // this same order but may be missing things.
4834 SmallVector<const void*, 32> IdealInitKeys;
4836 const CXXRecordDecl *ClassDecl = Constructor->getParent();
4838 // 1. Virtual bases.
4839 for (const auto &VBase : ClassDecl->vbases())
4840 IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, VBase.getType()));
4842 // 2. Non-virtual bases.
4843 for (const auto &Base : ClassDecl->bases()) {
4844 if (Base.isVirtual())
4846 IdealInitKeys.push_back(GetKeyForBase(SemaRef.Context, Base.getType()));
4849 // 3. Direct fields.
4850 for (auto *Field : ClassDecl->fields()) {
4851 if (Field->isUnnamedBitfield())
4854 PopulateKeysForFields(Field, IdealInitKeys);
4857 unsigned NumIdealInits = IdealInitKeys.size();
4858 unsigned IdealIndex = 0;
4860 CXXCtorInitializer *PrevInit = nullptr;
4861 for (unsigned InitIndex = 0; InitIndex != Inits.size(); ++InitIndex) {
4862 CXXCtorInitializer *Init = Inits[InitIndex];
4863 const void *InitKey = GetKeyForMember(SemaRef.Context, Init);
4865 // Scan forward to try to find this initializer in the idealized
4866 // initializers list.
4867 for (; IdealIndex != NumIdealInits; ++IdealIndex)
4868 if (InitKey == IdealInitKeys[IdealIndex])
4871 // If we didn't find this initializer, it must be because we
4872 // scanned past it on a previous iteration. That can only
4873 // happen if we're out of order; emit a warning.
4874 if (IdealIndex == NumIdealInits && PrevInit) {
4875 Sema::SemaDiagnosticBuilder D =
4876 SemaRef.Diag(PrevInit->getSourceLocation(),
4877 diag::warn_initializer_out_of_order);
4879 if (PrevInit->isAnyMemberInitializer())
4880 D << 0 << PrevInit->getAnyMember()->getDeclName();
4882 D << 1 << PrevInit->getTypeSourceInfo()->getType();
4884 if (Init->isAnyMemberInitializer())
4885 D << 0 << Init->getAnyMember()->getDeclName();
4887 D << 1 << Init->getTypeSourceInfo()->getType();
4889 // Move back to the initializer's location in the ideal list.
4890 for (IdealIndex = 0; IdealIndex != NumIdealInits; ++IdealIndex)
4891 if (InitKey == IdealInitKeys[IdealIndex])
4894 assert(IdealIndex < NumIdealInits &&
4895 "initializer not found in initializer list");
4903 bool CheckRedundantInit(Sema &S,
4904 CXXCtorInitializer *Init,
4905 CXXCtorInitializer *&PrevInit) {
4911 if (FieldDecl *Field = Init->getAnyMember())
4912 S.Diag(Init->getSourceLocation(),
4913 diag::err_multiple_mem_initialization)
4914 << Field->getDeclName()
4915 << Init->getSourceRange();
4917 const Type *BaseClass = Init->getBaseClass();
4918 assert(BaseClass && "neither field nor base");
4919 S.Diag(Init->getSourceLocation(),
4920 diag::err_multiple_base_initialization)
4921 << QualType(BaseClass, 0)
4922 << Init->getSourceRange();
4924 S.Diag(PrevInit->getSourceLocation(), diag::note_previous_initializer)
4925 << 0 << PrevInit->getSourceRange();
4930 typedef std::pair<NamedDecl *, CXXCtorInitializer *> UnionEntry;
4931 typedef llvm::DenseMap<RecordDecl*, UnionEntry> RedundantUnionMap;
4933 bool CheckRedundantUnionInit(Sema &S,
4934 CXXCtorInitializer *Init,
4935 RedundantUnionMap &Unions) {
4936 FieldDecl *Field = Init->getAnyMember();
4937 RecordDecl *Parent = Field->getParent();
4938 NamedDecl *Child = Field;
4940 while (Parent->isAnonymousStructOrUnion() || Parent->isUnion()) {
4941 if (Parent->isUnion()) {
4942 UnionEntry &En = Unions[Parent];
4943 if (En.first && En.first != Child) {
4944 S.Diag(Init->getSourceLocation(),
4945 diag::err_multiple_mem_union_initialization)
4946 << Field->getDeclName()
4947 << Init->getSourceRange();
4948 S.Diag(En.second->getSourceLocation(), diag::note_previous_initializer)
4949 << 0 << En.second->getSourceRange();
4956 if (!Parent->isAnonymousStructOrUnion())
4961 Parent = cast<RecordDecl>(Parent->getDeclContext());
4968 /// ActOnMemInitializers - Handle the member initializers for a constructor.
4969 void Sema::ActOnMemInitializers(Decl *ConstructorDecl,
4970 SourceLocation ColonLoc,
4971 ArrayRef<CXXCtorInitializer*> MemInits,
4973 if (!ConstructorDecl)
4976 AdjustDeclIfTemplate(ConstructorDecl);
4978 CXXConstructorDecl *Constructor
4979 = dyn_cast<CXXConstructorDecl>(ConstructorDecl);
4982 Diag(ColonLoc, diag::err_only_constructors_take_base_inits);
4986 // Mapping for the duplicate initializers check.
4987 // For member initializers, this is keyed with a FieldDecl*.
4988 // For base initializers, this is keyed with a Type*.
4989 llvm::DenseMap<const void *, CXXCtorInitializer *> Members;
4991 // Mapping for the inconsistent anonymous-union initializers check.
4992 RedundantUnionMap MemberUnions;
4994 bool HadError = false;
4995 for (unsigned i = 0; i < MemInits.size(); i++) {
4996 CXXCtorInitializer *Init = MemInits[i];
4998 // Set the source order index.
4999 Init->setSourceOrder(i);
5001 if (Init->isAnyMemberInitializer()) {
5002 const void *Key = GetKeyForMember(Context, Init);
5003 if (CheckRedundantInit(*this, Init, Members[Key]) ||
5004 CheckRedundantUnionInit(*this, Init, MemberUnions))
5006 } else if (Init->isBaseInitializer()) {
5007 const void *Key = GetKeyForMember(Context, Init);
5008 if (CheckRedundantInit(*this, Init, Members[Key]))
5011 assert(Init->isDelegatingInitializer());
5012 // This must be the only initializer
5013 if (MemInits.size() != 1) {
5014 Diag(Init->getSourceLocation(),
5015 diag::err_delegating_initializer_alone)
5016 << Init->getSourceRange() << MemInits[i ? 0 : 1]->getSourceRange();
5017 // We will treat this as being the only initializer.
5019 SetDelegatingInitializer(Constructor, MemInits[i]);
5020 // Return immediately as the initializer is set.
5028 DiagnoseBaseOrMemInitializerOrder(*this, Constructor, MemInits);
5030 SetCtorInitializers(Constructor, AnyErrors, MemInits);
5032 DiagnoseUninitializedFields(*this, Constructor);
5036 Sema::MarkBaseAndMemberDestructorsReferenced(SourceLocation Location,
5037 CXXRecordDecl *ClassDecl) {
5038 // Ignore dependent contexts. Also ignore unions, since their members never
5039 // have destructors implicitly called.
5040 if (ClassDecl->isDependentContext() || ClassDecl->isUnion())
5043 // FIXME: all the access-control diagnostics are positioned on the
5044 // field/base declaration. That's probably good; that said, the
5045 // user might reasonably want to know why the destructor is being
5046 // emitted, and we currently don't say.
5048 // Non-static data members.
5049 for (auto *Field : ClassDecl->fields()) {
5050 if (Field->isInvalidDecl())
5053 // Don't destroy incomplete or zero-length arrays.
5054 if (isIncompleteOrZeroLengthArrayType(Context, Field->getType()))
5057 QualType FieldType = Context.getBaseElementType(Field->getType());
5059 const RecordType* RT = FieldType->getAs<RecordType>();
5063 CXXRecordDecl *FieldClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5064 if (FieldClassDecl->isInvalidDecl())
5066 if (FieldClassDecl->hasIrrelevantDestructor())
5068 // The destructor for an implicit anonymous union member is never invoked.
5069 if (FieldClassDecl->isUnion() && FieldClassDecl->isAnonymousStructOrUnion())
5072 CXXDestructorDecl *Dtor = LookupDestructor(FieldClassDecl);
5073 assert(Dtor && "No dtor found for FieldClassDecl!");
5074 CheckDestructorAccess(Field->getLocation(), Dtor,
5075 PDiag(diag::err_access_dtor_field)
5076 << Field->getDeclName()
5079 MarkFunctionReferenced(Location, Dtor);
5080 DiagnoseUseOfDecl(Dtor, Location);
5083 // We only potentially invoke the destructors of potentially constructed
5085 bool VisitVirtualBases = !ClassDecl->isAbstract();
5087 llvm::SmallPtrSet<const RecordType *, 8> DirectVirtualBases;
5090 for (const auto &Base : ClassDecl->bases()) {
5091 // Bases are always records in a well-formed non-dependent class.
5092 const RecordType *RT = Base.getType()->getAs<RecordType>();
5094 // Remember direct virtual bases.
5095 if (Base.isVirtual()) {
5096 if (!VisitVirtualBases)
5098 DirectVirtualBases.insert(RT);
5101 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5102 // If our base class is invalid, we probably can't get its dtor anyway.
5103 if (BaseClassDecl->isInvalidDecl())
5105 if (BaseClassDecl->hasIrrelevantDestructor())
5108 CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
5109 assert(Dtor && "No dtor found for BaseClassDecl!");
5111 // FIXME: caret should be on the start of the class name
5112 CheckDestructorAccess(Base.getLocStart(), Dtor,
5113 PDiag(diag::err_access_dtor_base)
5115 << Base.getSourceRange(),
5116 Context.getTypeDeclType(ClassDecl));
5118 MarkFunctionReferenced(Location, Dtor);
5119 DiagnoseUseOfDecl(Dtor, Location);
5122 if (!VisitVirtualBases)
5126 for (const auto &VBase : ClassDecl->vbases()) {
5127 // Bases are always records in a well-formed non-dependent class.
5128 const RecordType *RT = VBase.getType()->castAs<RecordType>();
5130 // Ignore direct virtual bases.
5131 if (DirectVirtualBases.count(RT))
5134 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(RT->getDecl());
5135 // If our base class is invalid, we probably can't get its dtor anyway.
5136 if (BaseClassDecl->isInvalidDecl())
5138 if (BaseClassDecl->hasIrrelevantDestructor())
5141 CXXDestructorDecl *Dtor = LookupDestructor(BaseClassDecl);
5142 assert(Dtor && "No dtor found for BaseClassDecl!");
5143 if (CheckDestructorAccess(
5144 ClassDecl->getLocation(), Dtor,
5145 PDiag(diag::err_access_dtor_vbase)
5146 << Context.getTypeDeclType(ClassDecl) << VBase.getType(),
5147 Context.getTypeDeclType(ClassDecl)) ==
5149 CheckDerivedToBaseConversion(
5150 Context.getTypeDeclType(ClassDecl), VBase.getType(),
5151 diag::err_access_dtor_vbase, 0, ClassDecl->getLocation(),
5152 SourceRange(), DeclarationName(), nullptr);
5155 MarkFunctionReferenced(Location, Dtor);
5156 DiagnoseUseOfDecl(Dtor, Location);
5160 void Sema::ActOnDefaultCtorInitializers(Decl *CDtorDecl) {
5164 if (CXXConstructorDecl *Constructor
5165 = dyn_cast<CXXConstructorDecl>(CDtorDecl)) {
5166 SetCtorInitializers(Constructor, /*AnyErrors=*/false);
5167 DiagnoseUninitializedFields(*this, Constructor);
5171 bool Sema::isAbstractType(SourceLocation Loc, QualType T) {
5172 if (!getLangOpts().CPlusPlus)
5175 const auto *RD = Context.getBaseElementType(T)->getAsCXXRecordDecl();
5179 // FIXME: Per [temp.inst]p1, we are supposed to trigger instantiation of a
5180 // class template specialization here, but doing so breaks a lot of code.
5182 // We can't answer whether something is abstract until it has a
5183 // definition. If it's currently being defined, we'll walk back
5184 // over all the declarations when we have a full definition.
5185 const CXXRecordDecl *Def = RD->getDefinition();
5186 if (!Def || Def->isBeingDefined())
5189 return RD->isAbstract();
5192 bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T,
5193 TypeDiagnoser &Diagnoser) {
5194 if (!isAbstractType(Loc, T))
5197 T = Context.getBaseElementType(T);
5198 Diagnoser.diagnose(*this, Loc, T);
5199 DiagnoseAbstractType(T->getAsCXXRecordDecl());
5203 void Sema::DiagnoseAbstractType(const CXXRecordDecl *RD) {
5204 // Check if we've already emitted the list of pure virtual functions
5206 if (PureVirtualClassDiagSet && PureVirtualClassDiagSet->count(RD))
5209 // If the diagnostic is suppressed, don't emit the notes. We're only
5210 // going to emit them once, so try to attach them to a diagnostic we're
5211 // actually going to show.
5212 if (Diags.isLastDiagnosticIgnored())
5215 CXXFinalOverriderMap FinalOverriders;
5216 RD->getFinalOverriders(FinalOverriders);
5218 // Keep a set of seen pure methods so we won't diagnose the same method
5220 llvm::SmallPtrSet<const CXXMethodDecl *, 8> SeenPureMethods;
5222 for (CXXFinalOverriderMap::iterator M = FinalOverriders.begin(),
5223 MEnd = FinalOverriders.end();
5226 for (OverridingMethods::iterator SO = M->second.begin(),
5227 SOEnd = M->second.end();
5228 SO != SOEnd; ++SO) {
5229 // C++ [class.abstract]p4:
5230 // A class is abstract if it contains or inherits at least one
5231 // pure virtual function for which the final overrider is pure
5235 if (SO->second.size() != 1)
5238 if (!SO->second.front().Method->isPure())
5241 if (!SeenPureMethods.insert(SO->second.front().Method).second)
5244 Diag(SO->second.front().Method->getLocation(),
5245 diag::note_pure_virtual_function)
5246 << SO->second.front().Method->getDeclName() << RD->getDeclName();
5250 if (!PureVirtualClassDiagSet)
5251 PureVirtualClassDiagSet.reset(new RecordDeclSetTy);
5252 PureVirtualClassDiagSet->insert(RD);
5256 struct AbstractUsageInfo {
5258 CXXRecordDecl *Record;
5259 CanQualType AbstractType;
5262 AbstractUsageInfo(Sema &S, CXXRecordDecl *Record)
5263 : S(S), Record(Record),
5264 AbstractType(S.Context.getCanonicalType(
5265 S.Context.getTypeDeclType(Record))),
5268 void DiagnoseAbstractType() {
5269 if (Invalid) return;
5270 S.DiagnoseAbstractType(Record);
5274 void CheckType(const NamedDecl *D, TypeLoc TL, Sema::AbstractDiagSelID Sel);
5277 struct CheckAbstractUsage {
5278 AbstractUsageInfo &Info;
5279 const NamedDecl *Ctx;
5281 CheckAbstractUsage(AbstractUsageInfo &Info, const NamedDecl *Ctx)
5282 : Info(Info), Ctx(Ctx) {}
5284 void Visit(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
5285 switch (TL.getTypeLocClass()) {
5286 #define ABSTRACT_TYPELOC(CLASS, PARENT)
5287 #define TYPELOC(CLASS, PARENT) \
5288 case TypeLoc::CLASS: Check(TL.castAs<CLASS##TypeLoc>(), Sel); break;
5289 #include "clang/AST/TypeLocNodes.def"
5293 void Check(FunctionProtoTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5294 Visit(TL.getReturnLoc(), Sema::AbstractReturnType);
5295 for (unsigned I = 0, E = TL.getNumParams(); I != E; ++I) {
5296 if (!TL.getParam(I))
5299 TypeSourceInfo *TSI = TL.getParam(I)->getTypeSourceInfo();
5300 if (TSI) Visit(TSI->getTypeLoc(), Sema::AbstractParamType);
5304 void Check(ArrayTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5305 Visit(TL.getElementLoc(), Sema::AbstractArrayType);
5308 void Check(TemplateSpecializationTypeLoc TL, Sema::AbstractDiagSelID Sel) {
5309 // Visit the type parameters from a permissive context.
5310 for (unsigned I = 0, E = TL.getNumArgs(); I != E; ++I) {
5311 TemplateArgumentLoc TAL = TL.getArgLoc(I);
5312 if (TAL.getArgument().getKind() == TemplateArgument::Type)
5313 if (TypeSourceInfo *TSI = TAL.getTypeSourceInfo())
5314 Visit(TSI->getTypeLoc(), Sema::AbstractNone);
5315 // TODO: other template argument types?
5319 // Visit pointee types from a permissive context.
5320 #define CheckPolymorphic(Type) \
5321 void Check(Type TL, Sema::AbstractDiagSelID Sel) { \
5322 Visit(TL.getNextTypeLoc(), Sema::AbstractNone); \
5324 CheckPolymorphic(PointerTypeLoc)
5325 CheckPolymorphic(ReferenceTypeLoc)
5326 CheckPolymorphic(MemberPointerTypeLoc)
5327 CheckPolymorphic(BlockPointerTypeLoc)
5328 CheckPolymorphic(AtomicTypeLoc)
5330 /// Handle all the types we haven't given a more specific
5331 /// implementation for above.
5332 void Check(TypeLoc TL, Sema::AbstractDiagSelID Sel) {
5333 // Every other kind of type that we haven't called out already
5334 // that has an inner type is either (1) sugar or (2) contains that
5335 // inner type in some way as a subobject.
5336 if (TypeLoc Next = TL.getNextTypeLoc())
5337 return Visit(Next, Sel);
5339 // If there's no inner type and we're in a permissive context,
5341 if (Sel == Sema::AbstractNone) return;
5343 // Check whether the type matches the abstract type.
5344 QualType T = TL.getType();
5345 if (T->isArrayType()) {
5346 Sel = Sema::AbstractArrayType;
5347 T = Info.S.Context.getBaseElementType(T);
5349 CanQualType CT = T->getCanonicalTypeUnqualified().getUnqualifiedType();
5350 if (CT != Info.AbstractType) return;
5352 // It matched; do some magic.
5353 if (Sel == Sema::AbstractArrayType) {
5354 Info.S.Diag(Ctx->getLocation(), diag::err_array_of_abstract_type)
5355 << T << TL.getSourceRange();
5357 Info.S.Diag(Ctx->getLocation(), diag::err_abstract_type_in_decl)
5358 << Sel << T << TL.getSourceRange();
5360 Info.DiagnoseAbstractType();
5364 void AbstractUsageInfo::CheckType(const NamedDecl *D, TypeLoc TL,
5365 Sema::AbstractDiagSelID Sel) {
5366 CheckAbstractUsage(*this, D).Visit(TL, Sel);
5371 /// Check for invalid uses of an abstract type in a method declaration.
5372 static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
5373 CXXMethodDecl *MD) {
5374 // No need to do the check on definitions, which require that
5375 // the return/param types be complete.
5376 if (MD->doesThisDeclarationHaveABody())
5379 // For safety's sake, just ignore it if we don't have type source
5380 // information. This should never happen for non-implicit methods,
5382 if (TypeSourceInfo *TSI = MD->getTypeSourceInfo())
5383 Info.CheckType(MD, TSI->getTypeLoc(), Sema::AbstractNone);
5386 /// Check for invalid uses of an abstract type within a class definition.
5387 static void CheckAbstractClassUsage(AbstractUsageInfo &Info,
5388 CXXRecordDecl *RD) {
5389 for (auto *D : RD->decls()) {
5390 if (D->isImplicit()) continue;
5392 // Methods and method templates.
5393 if (isa<CXXMethodDecl>(D)) {
5394 CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(D));
5395 } else if (isa<FunctionTemplateDecl>(D)) {
5396 FunctionDecl *FD = cast<FunctionTemplateDecl>(D)->getTemplatedDecl();
5397 CheckAbstractClassUsage(Info, cast<CXXMethodDecl>(FD));
5399 // Fields and static variables.
5400 } else if (isa<FieldDecl>(D)) {
5401 FieldDecl *FD = cast<FieldDecl>(D);
5402 if (TypeSourceInfo *TSI = FD->getTypeSourceInfo())
5403 Info.CheckType(FD, TSI->getTypeLoc(), Sema::AbstractFieldType);
5404 } else if (isa<VarDecl>(D)) {
5405 VarDecl *VD = cast<VarDecl>(D);
5406 if (TypeSourceInfo *TSI = VD->getTypeSourceInfo())
5407 Info.CheckType(VD, TSI->getTypeLoc(), Sema::AbstractVariableType);
5409 // Nested classes and class templates.
5410 } else if (isa<CXXRecordDecl>(D)) {
5411 CheckAbstractClassUsage(Info, cast<CXXRecordDecl>(D));
5412 } else if (isa<ClassTemplateDecl>(D)) {
5413 CheckAbstractClassUsage(Info,
5414 cast<ClassTemplateDecl>(D)->getTemplatedDecl());
5419 static void ReferenceDllExportedMethods(Sema &S, CXXRecordDecl *Class) {
5420 Attr *ClassAttr = getDLLAttr(Class);
5424 assert(ClassAttr->getKind() == attr::DLLExport);
5426 TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
5428 if (TSK == TSK_ExplicitInstantiationDeclaration)
5429 // Don't go any further if this is just an explicit instantiation
5433 for (Decl *Member : Class->decls()) {
5434 auto *MD = dyn_cast<CXXMethodDecl>(Member);
5438 if (Member->getAttr<DLLExportAttr>()) {
5439 if (MD->isUserProvided()) {
5440 // Instantiate non-default class member functions ...
5442 // .. except for certain kinds of template specializations.
5443 if (TSK == TSK_ImplicitInstantiation && !ClassAttr->isInherited())
5446 S.MarkFunctionReferenced(Class->getLocation(), MD);
5448 // The function will be passed to the consumer when its definition is
5450 } else if (!MD->isTrivial() || MD->isExplicitlyDefaulted() ||
5451 MD->isCopyAssignmentOperator() ||
5452 MD->isMoveAssignmentOperator()) {
5453 // Synthesize and instantiate non-trivial implicit methods, explicitly
5454 // defaulted methods, and the copy and move assignment operators. The
5455 // latter are exported even if they are trivial, because the address of
5456 // an operator can be taken and should compare equal across libraries.
5457 DiagnosticErrorTrap Trap(S.Diags);
5458 S.MarkFunctionReferenced(Class->getLocation(), MD);
5459 if (Trap.hasErrorOccurred()) {
5460 S.Diag(ClassAttr->getLocation(), diag::note_due_to_dllexported_class)
5461 << Class->getName() << !S.getLangOpts().CPlusPlus11;
5465 // There is no later point when we will see the definition of this
5466 // function, so pass it to the consumer now.
5467 S.Consumer.HandleTopLevelDecl(DeclGroupRef(MD));
5473 static void checkForMultipleExportedDefaultConstructors(Sema &S,
5474 CXXRecordDecl *Class) {
5475 // Only the MS ABI has default constructor closures, so we don't need to do
5476 // this semantic checking anywhere else.
5477 if (!S.Context.getTargetInfo().getCXXABI().isMicrosoft())
5480 CXXConstructorDecl *LastExportedDefaultCtor = nullptr;
5481 for (Decl *Member : Class->decls()) {
5482 // Look for exported default constructors.
5483 auto *CD = dyn_cast<CXXConstructorDecl>(Member);
5484 if (!CD || !CD->isDefaultConstructor())
5486 auto *Attr = CD->getAttr<DLLExportAttr>();
5490 // If the class is non-dependent, mark the default arguments as ODR-used so
5491 // that we can properly codegen the constructor closure.
5492 if (!Class->isDependentContext()) {
5493 for (ParmVarDecl *PD : CD->parameters()) {
5494 (void)S.CheckCXXDefaultArgExpr(Attr->getLocation(), CD, PD);
5495 S.DiscardCleanupsInEvaluationContext();
5499 if (LastExportedDefaultCtor) {
5500 S.Diag(LastExportedDefaultCtor->getLocation(),
5501 diag::err_attribute_dll_ambiguous_default_ctor)
5503 S.Diag(CD->getLocation(), diag::note_entity_declared_at)
5504 << CD->getDeclName();
5507 LastExportedDefaultCtor = CD;
5511 /// \brief Check class-level dllimport/dllexport attribute.
5512 void Sema::checkClassLevelDLLAttribute(CXXRecordDecl *Class) {
5513 Attr *ClassAttr = getDLLAttr(Class);
5515 // MSVC inherits DLL attributes to partial class template specializations.
5516 if (Context.getTargetInfo().getCXXABI().isMicrosoft() && !ClassAttr) {
5517 if (auto *Spec = dyn_cast<ClassTemplatePartialSpecializationDecl>(Class)) {
5518 if (Attr *TemplateAttr =
5519 getDLLAttr(Spec->getSpecializedTemplate()->getTemplatedDecl())) {
5520 auto *A = cast<InheritableAttr>(TemplateAttr->clone(getASTContext()));
5521 A->setInherited(true);
5530 if (!Class->isExternallyVisible()) {
5531 Diag(Class->getLocation(), diag::err_attribute_dll_not_extern)
5532 << Class << ClassAttr;
5536 if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
5537 !ClassAttr->isInherited()) {
5538 // Diagnose dll attributes on members of class with dll attribute.
5539 for (Decl *Member : Class->decls()) {
5540 if (!isa<VarDecl>(Member) && !isa<CXXMethodDecl>(Member))
5542 InheritableAttr *MemberAttr = getDLLAttr(Member);
5543 if (!MemberAttr || MemberAttr->isInherited() || Member->isInvalidDecl())
5546 Diag(MemberAttr->getLocation(),
5547 diag::err_attribute_dll_member_of_dll_class)
5548 << MemberAttr << ClassAttr;
5549 Diag(ClassAttr->getLocation(), diag::note_previous_attribute);
5550 Member->setInvalidDecl();
5554 if (Class->getDescribedClassTemplate())
5555 // Don't inherit dll attribute until the template is instantiated.
5558 // The class is either imported or exported.
5559 const bool ClassExported = ClassAttr->getKind() == attr::DLLExport;
5561 TemplateSpecializationKind TSK = Class->getTemplateSpecializationKind();
5563 // Ignore explicit dllexport on explicit class template instantiation declarations.
5564 if (ClassExported && !ClassAttr->isInherited() &&
5565 TSK == TSK_ExplicitInstantiationDeclaration) {
5566 Class->dropAttr<DLLExportAttr>();
5570 // Force declaration of implicit members so they can inherit the attribute.
5571 ForceDeclarationOfImplicitMembers(Class);
5573 // FIXME: MSVC's docs say all bases must be exportable, but this doesn't
5574 // seem to be true in practice?
5576 for (Decl *Member : Class->decls()) {
5577 VarDecl *VD = dyn_cast<VarDecl>(Member);
5578 CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Member);
5580 // Only methods and static fields inherit the attributes.
5585 // Don't process deleted methods.
5586 if (MD->isDeleted())
5589 if (MD->isInlined()) {
5590 // MinGW does not import or export inline methods.
5591 if (!Context.getTargetInfo().getCXXABI().isMicrosoft() &&
5592 !Context.getTargetInfo().getTriple().isWindowsItaniumEnvironment())
5595 // MSVC versions before 2015 don't export the move assignment operators
5596 // and move constructor, so don't attempt to import/export them if
5597 // we have a definition.
5598 auto *Ctor = dyn_cast<CXXConstructorDecl>(MD);
5599 if ((MD->isMoveAssignmentOperator() ||
5600 (Ctor && Ctor->isMoveConstructor())) &&
5601 !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015))
5604 // MSVC2015 doesn't export trivial defaulted x-tor but copy assign
5605 // operator is exported anyway.
5606 if (getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015) &&
5607 (Ctor || isa<CXXDestructorDecl>(MD)) && MD->isTrivial())
5612 if (!cast<NamedDecl>(Member)->isExternallyVisible())
5615 if (!getDLLAttr(Member)) {
5617 cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
5618 NewAttr->setInherited(true);
5619 Member->addAttr(NewAttr);
5624 DelayedDllExportClasses.push_back(Class);
5627 /// \brief Perform propagation of DLL attributes from a derived class to a
5628 /// templated base class for MS compatibility.
5629 void Sema::propagateDLLAttrToBaseClassTemplate(
5630 CXXRecordDecl *Class, Attr *ClassAttr,
5631 ClassTemplateSpecializationDecl *BaseTemplateSpec, SourceLocation BaseLoc) {
5633 BaseTemplateSpec->getSpecializedTemplate()->getTemplatedDecl())) {
5634 // If the base class template has a DLL attribute, don't try to change it.
5638 auto TSK = BaseTemplateSpec->getSpecializationKind();
5639 if (!getDLLAttr(BaseTemplateSpec) &&
5640 (TSK == TSK_Undeclared || TSK == TSK_ExplicitInstantiationDeclaration ||
5641 TSK == TSK_ImplicitInstantiation)) {
5642 // The template hasn't been instantiated yet (or it has, but only as an
5643 // explicit instantiation declaration or implicit instantiation, which means
5644 // we haven't codegenned any members yet), so propagate the attribute.
5645 auto *NewAttr = cast<InheritableAttr>(ClassAttr->clone(getASTContext()));
5646 NewAttr->setInherited(true);
5647 BaseTemplateSpec->addAttr(NewAttr);
5649 // If the template is already instantiated, checkDLLAttributeRedeclaration()
5650 // needs to be run again to work see the new attribute. Otherwise this will
5651 // get run whenever the template is instantiated.
5652 if (TSK != TSK_Undeclared)
5653 checkClassLevelDLLAttribute(BaseTemplateSpec);
5658 if (getDLLAttr(BaseTemplateSpec)) {
5659 // The template has already been specialized or instantiated with an
5660 // attribute, explicitly or through propagation. We should not try to change
5665 // The template was previously instantiated or explicitly specialized without
5666 // a dll attribute, It's too late for us to add an attribute, so warn that
5667 // this is unsupported.
5668 Diag(BaseLoc, diag::warn_attribute_dll_instantiated_base_class)
5669 << BaseTemplateSpec->isExplicitSpecialization();
5670 Diag(ClassAttr->getLocation(), diag::note_attribute);
5671 if (BaseTemplateSpec->isExplicitSpecialization()) {
5672 Diag(BaseTemplateSpec->getLocation(),
5673 diag::note_template_class_explicit_specialization_was_here)
5674 << BaseTemplateSpec;
5676 Diag(BaseTemplateSpec->getPointOfInstantiation(),
5677 diag::note_template_class_instantiation_was_here)
5678 << BaseTemplateSpec;
5682 static void DefineImplicitSpecialMember(Sema &S, CXXMethodDecl *MD,
5683 SourceLocation DefaultLoc) {
5684 switch (S.getSpecialMember(MD)) {
5685 case Sema::CXXDefaultConstructor:
5686 S.DefineImplicitDefaultConstructor(DefaultLoc,
5687 cast<CXXConstructorDecl>(MD));
5689 case Sema::CXXCopyConstructor:
5690 S.DefineImplicitCopyConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
5692 case Sema::CXXCopyAssignment:
5693 S.DefineImplicitCopyAssignment(DefaultLoc, MD);
5695 case Sema::CXXDestructor:
5696 S.DefineImplicitDestructor(DefaultLoc, cast<CXXDestructorDecl>(MD));
5698 case Sema::CXXMoveConstructor:
5699 S.DefineImplicitMoveConstructor(DefaultLoc, cast<CXXConstructorDecl>(MD));
5701 case Sema::CXXMoveAssignment:
5702 S.DefineImplicitMoveAssignment(DefaultLoc, MD);
5704 case Sema::CXXInvalid:
5705 llvm_unreachable("Invalid special member.");
5709 /// \brief Perform semantic checks on a class definition that has been
5710 /// completing, introducing implicitly-declared members, checking for
5711 /// abstract types, etc.
5712 void Sema::CheckCompletedCXXClass(CXXRecordDecl *Record) {
5716 if (Record->isAbstract() && !Record->isInvalidDecl()) {
5717 AbstractUsageInfo Info(*this, Record);
5718 CheckAbstractClassUsage(Info, Record);
5721 // If this is not an aggregate type and has no user-declared constructor,
5722 // complain about any non-static data members of reference or const scalar
5723 // type, since they will never get initializers.
5724 if (!Record->isInvalidDecl() && !Record->isDependentType() &&
5725 !Record->isAggregate() && !Record->hasUserDeclaredConstructor() &&
5726 !Record->isLambda()) {
5727 bool Complained = false;
5728 for (const auto *F : Record->fields()) {
5729 if (F->hasInClassInitializer() || F->isUnnamedBitfield())
5732 if (F->getType()->isReferenceType() ||
5733 (F->getType().isConstQualified() && F->getType()->isScalarType())) {
5735 Diag(Record->getLocation(), diag::warn_no_constructor_for_refconst)
5736 << Record->getTagKind() << Record;
5740 Diag(F->getLocation(), diag::note_refconst_member_not_initialized)
5741 << F->getType()->isReferenceType()
5742 << F->getDeclName();
5747 if (Record->getIdentifier()) {
5748 // C++ [class.mem]p13:
5749 // If T is the name of a class, then each of the following shall have a
5750 // name different from T:
5751 // - every member of every anonymous union that is a member of class T.
5753 // C++ [class.mem]p14:
5754 // In addition, if class T has a user-declared constructor (12.1), every
5755 // non-static data member of class T shall have a name different from T.
5756 DeclContext::lookup_result R = Record->lookup(Record->getDeclName());
5757 for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E;
5760 if ((isa<FieldDecl>(D) && Record->hasUserDeclaredConstructor()) ||
5761 isa<IndirectFieldDecl>(D)) {
5762 Diag(D->getLocation(), diag::err_member_name_of_class)
5763 << D->getDeclName();
5769 // Warn if the class has virtual methods but non-virtual public destructor.
5770 if (Record->isPolymorphic() && !Record->isDependentType()) {
5771 CXXDestructorDecl *dtor = Record->getDestructor();
5772 if ((!dtor || (!dtor->isVirtual() && dtor->getAccess() == AS_public)) &&
5773 !Record->hasAttr<FinalAttr>())
5774 Diag(dtor ? dtor->getLocation() : Record->getLocation(),
5775 diag::warn_non_virtual_dtor) << Context.getRecordType(Record);
5778 if (Record->isAbstract()) {
5779 if (FinalAttr *FA = Record->getAttr<FinalAttr>()) {
5780 Diag(Record->getLocation(), diag::warn_abstract_final_class)
5781 << FA->isSpelledAsSealed();
5782 DiagnoseAbstractType(Record);
5786 bool HasMethodWithOverrideControl = false,
5787 HasOverridingMethodWithoutOverrideControl = false;
5788 if (!Record->isDependentType()) {
5789 for (auto *M : Record->methods()) {
5790 // See if a method overloads virtual methods in a base
5791 // class without overriding any.
5793 DiagnoseHiddenVirtualMethods(M);
5794 if (M->hasAttr<OverrideAttr>())
5795 HasMethodWithOverrideControl = true;
5796 else if (M->size_overridden_methods() > 0)
5797 HasOverridingMethodWithoutOverrideControl = true;
5798 // Check whether the explicitly-defaulted special members are valid.
5799 if (!M->isInvalidDecl() && M->isExplicitlyDefaulted())
5800 CheckExplicitlyDefaultedSpecialMember(M);
5802 // For an explicitly defaulted or deleted special member, we defer
5803 // determining triviality until the class is complete. That time is now!
5804 CXXSpecialMember CSM = getSpecialMember(M);
5805 if (!M->isImplicit() && !M->isUserProvided()) {
5806 if (CSM != CXXInvalid) {
5807 M->setTrivial(SpecialMemberIsTrivial(M, CSM));
5809 // Inform the class that we've finished declaring this member.
5810 Record->finishedDefaultedOrDeletedMember(M);
5814 if (!M->isInvalidDecl() && M->isExplicitlyDefaulted() &&
5815 M->hasAttr<DLLExportAttr>()) {
5816 if (getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015) &&
5818 (CSM == CXXDefaultConstructor || CSM == CXXCopyConstructor ||
5819 CSM == CXXDestructor))
5820 M->dropAttr<DLLExportAttr>();
5822 if (M->hasAttr<DLLExportAttr>()) {
5823 DefineImplicitSpecialMember(*this, M, M->getLocation());
5824 ActOnFinishInlineFunctionDef(M);
5830 if (HasMethodWithOverrideControl &&
5831 HasOverridingMethodWithoutOverrideControl) {
5832 // At least one method has the 'override' control declared.
5833 // Diagnose all other overridden methods which do not have 'override' specified on them.
5834 for (auto *M : Record->methods())
5835 DiagnoseAbsenceOfOverrideControl(M);
5838 // ms_struct is a request to use the same ABI rules as MSVC. Check
5839 // whether this class uses any C++ features that are implemented
5840 // completely differently in MSVC, and if so, emit a diagnostic.
5841 // That diagnostic defaults to an error, but we allow projects to
5842 // map it down to a warning (or ignore it). It's a fairly common
5843 // practice among users of the ms_struct pragma to mass-annotate
5844 // headers, sweeping up a bunch of types that the project doesn't
5845 // really rely on MSVC-compatible layout for. We must therefore
5846 // support "ms_struct except for C++ stuff" as a secondary ABI.
5847 if (Record->isMsStruct(Context) &&
5848 (Record->isPolymorphic() || Record->getNumBases())) {
5849 Diag(Record->getLocation(), diag::warn_cxx_ms_struct);
5852 checkClassLevelDLLAttribute(Record);
5855 /// Look up the special member function that would be called by a special
5856 /// member function for a subobject of class type.
5858 /// \param Class The class type of the subobject.
5859 /// \param CSM The kind of special member function.
5860 /// \param FieldQuals If the subobject is a field, its cv-qualifiers.
5861 /// \param ConstRHS True if this is a copy operation with a const object
5862 /// on its RHS, that is, if the argument to the outer special member
5863 /// function is 'const' and this is not a field marked 'mutable'.
5864 static Sema::SpecialMemberOverloadResult lookupCallFromSpecialMember(
5865 Sema &S, CXXRecordDecl *Class, Sema::CXXSpecialMember CSM,
5866 unsigned FieldQuals, bool ConstRHS) {
5867 unsigned LHSQuals = 0;
5868 if (CSM == Sema::CXXCopyAssignment || CSM == Sema::CXXMoveAssignment)
5869 LHSQuals = FieldQuals;
5871 unsigned RHSQuals = FieldQuals;
5872 if (CSM == Sema::CXXDefaultConstructor || CSM == Sema::CXXDestructor)
5875 RHSQuals |= Qualifiers::Const;
5877 return S.LookupSpecialMember(Class, CSM,
5878 RHSQuals & Qualifiers::Const,
5879 RHSQuals & Qualifiers::Volatile,
5881 LHSQuals & Qualifiers::Const,
5882 LHSQuals & Qualifiers::Volatile);
5885 class Sema::InheritedConstructorInfo {
5887 SourceLocation UseLoc;
5889 /// A mapping from the base classes through which the constructor was
5890 /// inherited to the using shadow declaration in that base class (or a null
5891 /// pointer if the constructor was declared in that base class).
5892 llvm::DenseMap<CXXRecordDecl *, ConstructorUsingShadowDecl *>
5896 InheritedConstructorInfo(Sema &S, SourceLocation UseLoc,
5897 ConstructorUsingShadowDecl *Shadow)
5898 : S(S), UseLoc(UseLoc) {
5899 bool DiagnosedMultipleConstructedBases = false;
5900 CXXRecordDecl *ConstructedBase = nullptr;
5901 UsingDecl *ConstructedBaseUsing = nullptr;
5903 // Find the set of such base class subobjects and check that there's a
5904 // unique constructed subobject.
5905 for (auto *D : Shadow->redecls()) {
5906 auto *DShadow = cast<ConstructorUsingShadowDecl>(D);
5907 auto *DNominatedBase = DShadow->getNominatedBaseClass();
5908 auto *DConstructedBase = DShadow->getConstructedBaseClass();
5910 InheritedFromBases.insert(
5911 std::make_pair(DNominatedBase->getCanonicalDecl(),
5912 DShadow->getNominatedBaseClassShadowDecl()));
5913 if (DShadow->constructsVirtualBase())
5914 InheritedFromBases.insert(
5915 std::make_pair(DConstructedBase->getCanonicalDecl(),
5916 DShadow->getConstructedBaseClassShadowDecl()));
5918 assert(DNominatedBase == DConstructedBase);
5920 // [class.inhctor.init]p2:
5921 // If the constructor was inherited from multiple base class subobjects
5922 // of type B, the program is ill-formed.
5923 if (!ConstructedBase) {
5924 ConstructedBase = DConstructedBase;
5925 ConstructedBaseUsing = D->getUsingDecl();
5926 } else if (ConstructedBase != DConstructedBase &&
5927 !Shadow->isInvalidDecl()) {
5928 if (!DiagnosedMultipleConstructedBases) {
5929 S.Diag(UseLoc, diag::err_ambiguous_inherited_constructor)
5930 << Shadow->getTargetDecl();
5931 S.Diag(ConstructedBaseUsing->getLocation(),
5932 diag::note_ambiguous_inherited_constructor_using)
5934 DiagnosedMultipleConstructedBases = true;
5936 S.Diag(D->getUsingDecl()->getLocation(),
5937 diag::note_ambiguous_inherited_constructor_using)
5938 << DConstructedBase;
5942 if (DiagnosedMultipleConstructedBases)
5943 Shadow->setInvalidDecl();
5946 /// Find the constructor to use for inherited construction of a base class,
5947 /// and whether that base class constructor inherits the constructor from a
5948 /// virtual base class (in which case it won't actually invoke it).
5949 std::pair<CXXConstructorDecl *, bool>
5950 findConstructorForBase(CXXRecordDecl *Base, CXXConstructorDecl *Ctor) const {
5951 auto It = InheritedFromBases.find(Base->getCanonicalDecl());
5952 if (It == InheritedFromBases.end())
5953 return std::make_pair(nullptr, false);
5955 // This is an intermediary class.
5957 return std::make_pair(
5958 S.findInheritingConstructor(UseLoc, Ctor, It->second),
5959 It->second->constructsVirtualBase());
5961 // This is the base class from which the constructor was inherited.
5962 return std::make_pair(Ctor, false);
5966 /// Is the special member function which would be selected to perform the
5967 /// specified operation on the specified class type a constexpr constructor?
5969 specialMemberIsConstexpr(Sema &S, CXXRecordDecl *ClassDecl,
5970 Sema::CXXSpecialMember CSM, unsigned Quals,
5972 CXXConstructorDecl *InheritedCtor = nullptr,
5973 Sema::InheritedConstructorInfo *Inherited = nullptr) {
5974 // If we're inheriting a constructor, see if we need to call it for this base
5976 if (InheritedCtor) {
5977 assert(CSM == Sema::CXXDefaultConstructor);
5979 Inherited->findConstructorForBase(ClassDecl, InheritedCtor).first;
5981 return BaseCtor->isConstexpr();
5984 if (CSM == Sema::CXXDefaultConstructor)
5985 return ClassDecl->hasConstexprDefaultConstructor();
5987 Sema::SpecialMemberOverloadResult SMOR =
5988 lookupCallFromSpecialMember(S, ClassDecl, CSM, Quals, ConstRHS);
5989 if (!SMOR.getMethod())
5990 // A constructor we wouldn't select can't be "involved in initializing"
5993 return SMOR.getMethod()->isConstexpr();
5996 /// Determine whether the specified special member function would be constexpr
5997 /// if it were implicitly defined.
5998 static bool defaultedSpecialMemberIsConstexpr(
5999 Sema &S, CXXRecordDecl *ClassDecl, Sema::CXXSpecialMember CSM,
6000 bool ConstArg, CXXConstructorDecl *InheritedCtor = nullptr,
6001 Sema::InheritedConstructorInfo *Inherited = nullptr) {
6002 if (!S.getLangOpts().CPlusPlus11)
6005 // C++11 [dcl.constexpr]p4:
6006 // In the definition of a constexpr constructor [...]
6009 case Sema::CXXDefaultConstructor:
6012 // Since default constructor lookup is essentially trivial (and cannot
6013 // involve, for instance, template instantiation), we compute whether a
6014 // defaulted default constructor is constexpr directly within CXXRecordDecl.
6016 // This is important for performance; we need to know whether the default
6017 // constructor is constexpr to determine whether the type is a literal type.
6018 return ClassDecl->defaultedDefaultConstructorIsConstexpr();
6020 case Sema::CXXCopyConstructor:
6021 case Sema::CXXMoveConstructor:
6022 // For copy or move constructors, we need to perform overload resolution.
6025 case Sema::CXXCopyAssignment:
6026 case Sema::CXXMoveAssignment:
6027 if (!S.getLangOpts().CPlusPlus14)
6029 // In C++1y, we need to perform overload resolution.
6033 case Sema::CXXDestructor:
6034 case Sema::CXXInvalid:
6038 // -- if the class is a non-empty union, or for each non-empty anonymous
6039 // union member of a non-union class, exactly one non-static data member
6040 // shall be initialized; [DR1359]
6042 // If we squint, this is guaranteed, since exactly one non-static data member
6043 // will be initialized (if the constructor isn't deleted), we just don't know
6045 if (Ctor && ClassDecl->isUnion())
6046 return CSM == Sema::CXXDefaultConstructor
6047 ? ClassDecl->hasInClassInitializer() ||
6048 !ClassDecl->hasVariantMembers()
6051 // -- the class shall not have any virtual base classes;
6052 if (Ctor && ClassDecl->getNumVBases())
6055 // C++1y [class.copy]p26:
6056 // -- [the class] is a literal type, and
6057 if (!Ctor && !ClassDecl->isLiteral())
6060 // -- every constructor involved in initializing [...] base class
6061 // sub-objects shall be a constexpr constructor;
6062 // -- the assignment operator selected to copy/move each direct base
6063 // class is a constexpr function, and
6064 for (const auto &B : ClassDecl->bases()) {
6065 const RecordType *BaseType = B.getType()->getAs<RecordType>();
6066 if (!BaseType) continue;
6068 CXXRecordDecl *BaseClassDecl = cast<CXXRecordDecl>(BaseType->getDecl());
6069 if (!specialMemberIsConstexpr(S, BaseClassDecl, CSM, 0, ConstArg,
6070 InheritedCtor, Inherited))
6074 // -- every constructor involved in initializing non-static data members
6075 // [...] shall be a constexpr constructor;
6076 // -- every non-static data member and base class sub-object shall be
6078 // -- for each non-static data member of X that is of class type (or array
6079 // thereof), the assignment operator selected to copy/move that member is
6080 // a constexpr function
6081 for (const auto *F : ClassDecl->fields()) {
6082 if (F->isInvalidDecl())
6084 if (CSM == Sema::CXXDefaultConstructor && F->hasInClassInitializer())
6086 QualType BaseType = S.Context.getBaseElementType(F->getType());
6087 if (const RecordType *RecordTy = BaseType->getAs<RecordType>()) {
6088 CXXRecordDecl *FieldRecDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
6089 if (!specialMemberIsConstexpr(S, FieldRecDecl, CSM,
6090 BaseType.getCVRQualifiers(),
6091 ConstArg && !F->isMutable()))
6093 } else if (CSM == Sema::CXXDefaultConstructor) {
6098 // All OK, it's constexpr!
6102 static Sema::ImplicitExceptionSpecification
6103 ComputeDefaultedSpecialMemberExceptionSpec(
6104 Sema &S, SourceLocation Loc, CXXMethodDecl *MD, Sema::CXXSpecialMember CSM,
6105 Sema::InheritedConstructorInfo *ICI);
6107 static Sema::ImplicitExceptionSpecification
6108 computeImplicitExceptionSpec(Sema &S, SourceLocation Loc, CXXMethodDecl *MD) {
6109 auto CSM = S.getSpecialMember(MD);
6110 if (CSM != Sema::CXXInvalid)
6111 return ComputeDefaultedSpecialMemberExceptionSpec(S, Loc, MD, CSM, nullptr);
6113 auto *CD = cast<CXXConstructorDecl>(MD);
6114 assert(CD->getInheritedConstructor() &&
6115 "only special members have implicit exception specs");
6116 Sema::InheritedConstructorInfo ICI(
6117 S, Loc, CD->getInheritedConstructor().getShadowDecl());
6118 return ComputeDefaultedSpecialMemberExceptionSpec(
6119 S, Loc, CD, Sema::CXXDefaultConstructor, &ICI);
6122 static FunctionProtoType::ExtProtoInfo getImplicitMethodEPI(Sema &S,
6123 CXXMethodDecl *MD) {
6124 FunctionProtoType::ExtProtoInfo EPI;
6126 // Build an exception specification pointing back at this member.
6127 EPI.ExceptionSpec.Type = EST_Unevaluated;
6128 EPI.ExceptionSpec.SourceDecl = MD;
6130 // Set the calling convention to the default for C++ instance methods.
6131 EPI.ExtInfo = EPI.ExtInfo.withCallingConv(
6132 S.Context.getDefaultCallingConvention(/*IsVariadic=*/false,
6133 /*IsCXXMethod=*/true));
6137 void Sema::EvaluateImplicitExceptionSpec(SourceLocation Loc, CXXMethodDecl *MD) {
6138 const FunctionProtoType *FPT = MD->getType()->castAs<FunctionProtoType>();
6139 if (FPT->getExceptionSpecType() != EST_Unevaluated)
6142 // Evaluate the exception specification.
6143 auto IES = computeImplicitExceptionSpec(*this, Loc, MD);
6144 auto ESI = IES.getExceptionSpec();
6146 // Update the type of the special member to use it.
6147 UpdateExceptionSpec(MD, ESI);
6149 // A user-provided destructor can be defined outside the class. When that
6150 // happens, be sure to update the exception specification on both
6152 const FunctionProtoType *CanonicalFPT =
6153 MD->getCanonicalDecl()->getType()->castAs<FunctionProtoType>();
6154 if (CanonicalFPT->getExceptionSpecType() == EST_Unevaluated)
6155 UpdateExceptionSpec(MD->getCanonicalDecl(), ESI);
6158 void Sema::CheckExplicitlyDefaultedSpecialMember(CXXMethodDecl *MD) {
6159 CXXRecordDecl *RD = MD->getParent();
6160 CXXSpecialMember CSM = getSpecialMember(MD);
6162 assert(MD->isExplicitlyDefaulted() && CSM != CXXInvalid &&
6163 "not an explicitly-defaulted special member");
6165 // Whether this was the first-declared instance of the constructor.
6166 // This affects whether we implicitly add an exception spec and constexpr.
6167 bool First = MD == MD->getCanonicalDecl();
6169 bool HadError = false;
6171 // C++11 [dcl.fct.def.default]p1:
6172 // A function that is explicitly defaulted shall
6173 // -- be a special member function (checked elsewhere),
6174 // -- have the same type (except for ref-qualifiers, and except that a
6175 // copy operation can take a non-const reference) as an implicit
6177 // -- not have default arguments.
6178 unsigned ExpectedParams = 1;
6179 if (CSM == CXXDefaultConstructor || CSM == CXXDestructor)
6181 if (MD->getNumParams() != ExpectedParams) {
6182 // This also checks for default arguments: a copy or move constructor with a
6183 // default argument is classified as a default constructor, and assignment
6184 // operations and destructors can't have default arguments.
6185 Diag(MD->getLocation(), diag::err_defaulted_special_member_params)
6186 << CSM << MD->getSourceRange();
6188 } else if (MD->isVariadic()) {
6189 Diag(MD->getLocation(), diag::err_defaulted_special_member_variadic)
6190 << CSM << MD->getSourceRange();
6194 const FunctionProtoType *Type = MD->getType()->getAs<FunctionProtoType>();
6196 bool CanHaveConstParam = false;
6197 if (CSM == CXXCopyConstructor)
6198 CanHaveConstParam = RD->implicitCopyConstructorHasConstParam();
6199 else if (CSM == CXXCopyAssignment)
6200 CanHaveConstParam = RD->implicitCopyAssignmentHasConstParam();
6202 QualType ReturnType = Context.VoidTy;
6203 if (CSM == CXXCopyAssignment || CSM == CXXMoveAssignment) {
6204 // Check for return type matching.
6205 ReturnType = Type->getReturnType();
6206 QualType ExpectedReturnType =
6207 Context.getLValueReferenceType(Context.getTypeDeclType(RD));
6208 if (!Context.hasSameType(ReturnType, ExpectedReturnType)) {
6209 Diag(MD->getLocation(), diag::err_defaulted_special_member_return_type)
6210 << (CSM == CXXMoveAssignment) << ExpectedReturnType;
6214 // A defaulted special member cannot have cv-qualifiers.
6215 if (Type->getTypeQuals()) {
6216 Diag(MD->getLocation(), diag::err_defaulted_special_member_quals)
6217 << (CSM == CXXMoveAssignment) << getLangOpts().CPlusPlus14;
6222 // Check for parameter type matching.
6223 QualType ArgType = ExpectedParams ? Type->getParamType(0) : QualType();
6224 bool HasConstParam = false;
6225 if (ExpectedParams && ArgType->isReferenceType()) {
6226 // Argument must be reference to possibly-const T.
6227 QualType ReferentType = ArgType->getPointeeType();
6228 HasConstParam = ReferentType.isConstQualified();
6230 if (ReferentType.isVolatileQualified()) {
6231 Diag(MD->getLocation(),
6232 diag::err_defaulted_special_member_volatile_param) << CSM;
6236 if (HasConstParam && !CanHaveConstParam) {
6237 if (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment) {
6238 Diag(MD->getLocation(),
6239 diag::err_defaulted_special_member_copy_const_param)
6240 << (CSM == CXXCopyAssignment);
6241 // FIXME: Explain why this special member can't be const.
6243 Diag(MD->getLocation(),
6244 diag::err_defaulted_special_member_move_const_param)
6245 << (CSM == CXXMoveAssignment);
6249 } else if (ExpectedParams) {
6250 // A copy assignment operator can take its argument by value, but a
6251 // defaulted one cannot.
6252 assert(CSM == CXXCopyAssignment && "unexpected non-ref argument");
6253 Diag(MD->getLocation(), diag::err_defaulted_copy_assign_not_ref);
6257 // C++11 [dcl.fct.def.default]p2:
6258 // An explicitly-defaulted function may be declared constexpr only if it
6259 // would have been implicitly declared as constexpr,
6260 // Do not apply this rule to members of class templates, since core issue 1358
6261 // makes such functions always instantiate to constexpr functions. For
6262 // functions which cannot be constexpr (for non-constructors in C++11 and for
6263 // destructors in C++1y), this is checked elsewhere.
6264 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, RD, CSM,
6266 if ((getLangOpts().CPlusPlus14 ? !isa<CXXDestructorDecl>(MD)
6267 : isa<CXXConstructorDecl>(MD)) &&
6268 MD->isConstexpr() && !Constexpr &&
6269 MD->getTemplatedKind() == FunctionDecl::TK_NonTemplate) {
6270 Diag(MD->getLocStart(), diag::err_incorrect_defaulted_constexpr) << CSM;
6271 // FIXME: Explain why the special member can't be constexpr.
6275 // and may have an explicit exception-specification only if it is compatible
6276 // with the exception-specification on the implicit declaration.
6277 if (Type->hasExceptionSpec()) {
6278 // Delay the check if this is the first declaration of the special member,
6279 // since we may not have parsed some necessary in-class initializers yet.
6281 // If the exception specification needs to be instantiated, do so now,
6282 // before we clobber it with an EST_Unevaluated specification below.
6283 if (Type->getExceptionSpecType() == EST_Uninstantiated) {
6284 InstantiateExceptionSpec(MD->getLocStart(), MD);
6285 Type = MD->getType()->getAs<FunctionProtoType>();
6287 DelayedDefaultedMemberExceptionSpecs.push_back(std::make_pair(MD, Type));
6289 CheckExplicitlyDefaultedMemberExceptionSpec(MD, Type);
6292 // If a function is explicitly defaulted on its first declaration,
6294 // -- it is implicitly considered to be constexpr if the implicit
6295 // definition would be,
6296 MD->setConstexpr(Constexpr);
6298 // -- it is implicitly considered to have the same exception-specification
6299 // as if it had been implicitly declared,
6300 FunctionProtoType::ExtProtoInfo EPI = Type->getExtProtoInfo();
6301 EPI.ExceptionSpec.Type = EST_Unevaluated;
6302 EPI.ExceptionSpec.SourceDecl = MD;
6303 MD->setType(Context.getFunctionType(ReturnType,
6304 llvm::makeArrayRef(&ArgType,
6309 if (ShouldDeleteSpecialMember(MD, CSM)) {
6311 SetDeclDeleted(MD, MD->getLocation());
6313 // C++11 [dcl.fct.def.default]p4:
6314 // [For a] user-provided explicitly-defaulted function [...] if such a
6315 // function is implicitly defined as deleted, the program is ill-formed.
6316 Diag(MD->getLocation(), diag::err_out_of_line_default_deletes) << CSM;
6317 ShouldDeleteSpecialMember(MD, CSM, nullptr, /*Diagnose*/true);
6323 MD->setInvalidDecl();
6326 /// Check whether the exception specification provided for an
6327 /// explicitly-defaulted special member matches the exception specification
6328 /// that would have been generated for an implicit special member, per
6329 /// C++11 [dcl.fct.def.default]p2.
6330 void Sema::CheckExplicitlyDefaultedMemberExceptionSpec(
6331 CXXMethodDecl *MD, const FunctionProtoType *SpecifiedType) {
6332 // If the exception specification was explicitly specified but hadn't been
6333 // parsed when the method was defaulted, grab it now.
6334 if (SpecifiedType->getExceptionSpecType() == EST_Unparsed)
6336 MD->getTypeSourceInfo()->getType()->castAs<FunctionProtoType>();
6338 // Compute the implicit exception specification.
6339 CallingConv CC = Context.getDefaultCallingConvention(/*IsVariadic=*/false,
6340 /*IsCXXMethod=*/true);
6341 FunctionProtoType::ExtProtoInfo EPI(CC);
6342 auto IES = computeImplicitExceptionSpec(*this, MD->getLocation(), MD);
6343 EPI.ExceptionSpec = IES.getExceptionSpec();
6344 const FunctionProtoType *ImplicitType = cast<FunctionProtoType>(
6345 Context.getFunctionType(Context.VoidTy, None, EPI));
6347 // Ensure that it matches.
6348 CheckEquivalentExceptionSpec(
6349 PDiag(diag::err_incorrect_defaulted_exception_spec)
6350 << getSpecialMember(MD), PDiag(),
6351 ImplicitType, SourceLocation(),
6352 SpecifiedType, MD->getLocation());
6355 void Sema::CheckDelayedMemberExceptionSpecs() {
6356 decltype(DelayedExceptionSpecChecks) Checks;
6357 decltype(DelayedDefaultedMemberExceptionSpecs) Specs;
6359 std::swap(Checks, DelayedExceptionSpecChecks);
6360 std::swap(Specs, DelayedDefaultedMemberExceptionSpecs);
6362 // Perform any deferred checking of exception specifications for virtual
6364 for (auto &Check : Checks)
6365 CheckOverridingFunctionExceptionSpec(Check.first, Check.second);
6367 // Check that any explicitly-defaulted methods have exception specifications
6368 // compatible with their implicit exception specifications.
6369 for (auto &Spec : Specs)
6370 CheckExplicitlyDefaultedMemberExceptionSpec(Spec.first, Spec.second);
6374 /// CRTP base class for visiting operations performed by a special member
6375 /// function (or inherited constructor).
6376 template<typename Derived>
6377 struct SpecialMemberVisitor {
6380 Sema::CXXSpecialMember CSM;
6381 Sema::InheritedConstructorInfo *ICI;
6383 // Properties of the special member, computed for convenience.
6384 bool IsConstructor = false, IsAssignment = false, ConstArg = false;
6386 SpecialMemberVisitor(Sema &S, CXXMethodDecl *MD, Sema::CXXSpecialMember CSM,
6387 Sema::InheritedConstructorInfo *ICI)
6388 : S(S), MD(MD), CSM(CSM), ICI(ICI) {
6390 case Sema::CXXDefaultConstructor:
6391 case Sema::CXXCopyConstructor:
6392 case Sema::CXXMoveConstructor:
6393 IsConstructor = true;
6395 case Sema::CXXCopyAssignment:
6396 case Sema::CXXMoveAssignment:
6397 IsAssignment = true;
6399 case Sema::CXXDestructor:
6401 case Sema::CXXInvalid:
6402 llvm_unreachable("invalid special member kind");
6405 if (MD->getNumParams()) {
6406 if (const ReferenceType *RT =
6407 MD->getParamDecl(0)->getType()->getAs<ReferenceType>())
6408 ConstArg = RT->getPointeeType().isConstQualified();
6412 Derived &getDerived() { return static_cast<Derived&>(*this); }
6414 /// Is this a "move" special member?
6415 bool isMove() const {
6416 return CSM == Sema::CXXMoveConstructor || CSM == Sema::CXXMoveAssignment;
6419 /// Look up the corresponding special member in the given class.
6420 Sema::SpecialMemberOverloadResult lookupIn(CXXRecordDecl *Class,
6421 unsigned Quals, bool IsMutable) {
6422 return lookupCallFromSpecialMember(S, Class, CSM, Quals,
6423 ConstArg && !IsMutable);
6426 /// Look up the constructor for the specified base class to see if it's
6427 /// overridden due to this being an inherited constructor.
6428 Sema::SpecialMemberOverloadResult lookupInheritedCtor(CXXRecordDecl *Class) {
6431 assert(CSM == Sema::CXXDefaultConstructor);
6433 cast<CXXConstructorDecl>(MD)->getInheritedConstructor().getConstructor();
6434 if (auto *MD = ICI->findConstructorForBase(Class, BaseCtor).first)
6439 /// A base or member subobject.
6440 typedef llvm::PointerUnion<CXXBaseSpecifier*, FieldDecl*> Subobject;
6442 /// Get the location to use for a subobject in diagnostics.
6443 static SourceLocation getSubobjectLoc(Subobject Subobj) {
6444 // FIXME: For an indirect virtual base, the direct base leading to
6445 // the indirect virtual base would be a more useful choice.
6446 if (auto *B = Subobj.dyn_cast<CXXBaseSpecifier*>())
6447 return B->getBaseTypeLoc();
6449 return Subobj.get<FieldDecl*>()->getLocation();
6453 /// Visit all non-virtual (direct) bases.
6454 VisitNonVirtualBases,
6455 /// Visit all direct bases, virtual or not.
6457 /// Visit all non-virtual bases, and all virtual bases if the class
6458 /// is not abstract.
6459 VisitPotentiallyConstructedBases,
6460 /// Visit all direct or virtual bases.
6464 // Visit the bases and members of the class.
6465 bool visit(BasesToVisit Bases) {
6466 CXXRecordDecl *RD = MD->getParent();
6468 if (Bases == VisitPotentiallyConstructedBases)
6469 Bases = RD->isAbstract() ? VisitNonVirtualBases : VisitAllBases;
6471 for (auto &B : RD->bases())
6472 if ((Bases == VisitDirectBases || !B.isVirtual()) &&
6473 getDerived().visitBase(&B))
6476 if (Bases == VisitAllBases)
6477 for (auto &B : RD->vbases())
6478 if (getDerived().visitBase(&B))
6481 for (auto *F : RD->fields())
6482 if (!F->isInvalidDecl() && !F->isUnnamedBitfield() &&
6483 getDerived().visitField(F))
6492 struct SpecialMemberDeletionInfo
6493 : SpecialMemberVisitor<SpecialMemberDeletionInfo> {
6498 bool AllFieldsAreConst;
6500 SpecialMemberDeletionInfo(Sema &S, CXXMethodDecl *MD,
6501 Sema::CXXSpecialMember CSM,
6502 Sema::InheritedConstructorInfo *ICI, bool Diagnose)
6503 : SpecialMemberVisitor(S, MD, CSM, ICI), Diagnose(Diagnose),
6504 Loc(MD->getLocation()), AllFieldsAreConst(true) {}
6506 bool inUnion() const { return MD->getParent()->isUnion(); }
6508 Sema::CXXSpecialMember getEffectiveCSM() {
6509 return ICI ? Sema::CXXInvalid : CSM;
6512 bool visitBase(CXXBaseSpecifier *Base) { return shouldDeleteForBase(Base); }
6513 bool visitField(FieldDecl *Field) { return shouldDeleteForField(Field); }
6515 bool shouldDeleteForBase(CXXBaseSpecifier *Base);
6516 bool shouldDeleteForField(FieldDecl *FD);
6517 bool shouldDeleteForAllConstMembers();
6519 bool shouldDeleteForClassSubobject(CXXRecordDecl *Class, Subobject Subobj,
6521 bool shouldDeleteForSubobjectCall(Subobject Subobj,
6522 Sema::SpecialMemberOverloadResult SMOR,
6523 bool IsDtorCallInCtor);
6525 bool isAccessible(Subobject Subobj, CXXMethodDecl *D);
6529 /// Is the given special member inaccessible when used on the given
6531 bool SpecialMemberDeletionInfo::isAccessible(Subobject Subobj,
6532 CXXMethodDecl *target) {
6533 /// If we're operating on a base class, the object type is the
6534 /// type of this special member.
6536 AccessSpecifier access = target->getAccess();
6537 if (CXXBaseSpecifier *base = Subobj.dyn_cast<CXXBaseSpecifier*>()) {
6538 objectTy = S.Context.getTypeDeclType(MD->getParent());
6539 access = CXXRecordDecl::MergeAccess(base->getAccessSpecifier(), access);
6541 // If we're operating on a field, the object type is the type of the field.
6543 objectTy = S.Context.getTypeDeclType(target->getParent());
6546 return S.isSpecialMemberAccessibleForDeletion(target, access, objectTy);
6549 /// Check whether we should delete a special member due to the implicit
6550 /// definition containing a call to a special member of a subobject.
6551 bool SpecialMemberDeletionInfo::shouldDeleteForSubobjectCall(
6552 Subobject Subobj, Sema::SpecialMemberOverloadResult SMOR,
6553 bool IsDtorCallInCtor) {
6554 CXXMethodDecl *Decl = SMOR.getMethod();
6555 FieldDecl *Field = Subobj.dyn_cast<FieldDecl*>();
6559 if (SMOR.getKind() == Sema::SpecialMemberOverloadResult::NoMemberOrDeleted)
6560 DiagKind = !Decl ? 0 : 1;
6561 else if (SMOR.getKind() == Sema::SpecialMemberOverloadResult::Ambiguous)
6563 else if (!isAccessible(Subobj, Decl))
6565 else if (!IsDtorCallInCtor && Field && Field->getParent()->isUnion() &&
6566 !Decl->isTrivial()) {
6567 // A member of a union must have a trivial corresponding special member.
6568 // As a weird special case, a destructor call from a union's constructor
6569 // must be accessible and non-deleted, but need not be trivial. Such a
6570 // destructor is never actually called, but is semantically checked as
6580 S.Diag(Field->getLocation(),
6581 diag::note_deleted_special_member_class_subobject)
6582 << getEffectiveCSM() << MD->getParent() << /*IsField*/true
6583 << Field << DiagKind << IsDtorCallInCtor;
6585 CXXBaseSpecifier *Base = Subobj.get<CXXBaseSpecifier*>();
6586 S.Diag(Base->getLocStart(),
6587 diag::note_deleted_special_member_class_subobject)
6588 << getEffectiveCSM() << MD->getParent() << /*IsField*/false
6589 << Base->getType() << DiagKind << IsDtorCallInCtor;
6593 S.NoteDeletedFunction(Decl);
6594 // FIXME: Explain inaccessibility if DiagKind == 3.
6600 /// Check whether we should delete a special member function due to having a
6601 /// direct or virtual base class or non-static data member of class type M.
6602 bool SpecialMemberDeletionInfo::shouldDeleteForClassSubobject(
6603 CXXRecordDecl *Class, Subobject Subobj, unsigned Quals) {
6604 FieldDecl *Field = Subobj.dyn_cast<FieldDecl*>();
6605 bool IsMutable = Field && Field->isMutable();
6607 // C++11 [class.ctor]p5:
6608 // -- any direct or virtual base class, or non-static data member with no
6609 // brace-or-equal-initializer, has class type M (or array thereof) and
6610 // either M has no default constructor or overload resolution as applied
6611 // to M's default constructor results in an ambiguity or in a function
6612 // that is deleted or inaccessible
6613 // C++11 [class.copy]p11, C++11 [class.copy]p23:
6614 // -- a direct or virtual base class B that cannot be copied/moved because
6615 // overload resolution, as applied to B's corresponding special member,
6616 // results in an ambiguity or a function that is deleted or inaccessible
6617 // from the defaulted special member
6618 // C++11 [class.dtor]p5:
6619 // -- any direct or virtual base class [...] has a type with a destructor
6620 // that is deleted or inaccessible
6621 if (!(CSM == Sema::CXXDefaultConstructor &&
6622 Field && Field->hasInClassInitializer()) &&
6623 shouldDeleteForSubobjectCall(Subobj, lookupIn(Class, Quals, IsMutable),
6627 // C++11 [class.ctor]p5, C++11 [class.copy]p11:
6628 // -- any direct or virtual base class or non-static data member has a
6629 // type with a destructor that is deleted or inaccessible
6630 if (IsConstructor) {
6631 Sema::SpecialMemberOverloadResult SMOR =
6632 S.LookupSpecialMember(Class, Sema::CXXDestructor,
6633 false, false, false, false, false);
6634 if (shouldDeleteForSubobjectCall(Subobj, SMOR, true))
6641 /// Check whether we should delete a special member function due to the class
6642 /// having a particular direct or virtual base class.
6643 bool SpecialMemberDeletionInfo::shouldDeleteForBase(CXXBaseSpecifier *Base) {
6644 CXXRecordDecl *BaseClass = Base->getType()->getAsCXXRecordDecl();
6645 // If program is correct, BaseClass cannot be null, but if it is, the error
6646 // must be reported elsewhere.
6649 // If we have an inheriting constructor, check whether we're calling an
6650 // inherited constructor instead of a default constructor.
6651 Sema::SpecialMemberOverloadResult SMOR = lookupInheritedCtor(BaseClass);
6652 if (auto *BaseCtor = SMOR.getMethod()) {
6653 // Note that we do not check access along this path; other than that,
6654 // this is the same as shouldDeleteForSubobjectCall(Base, BaseCtor, false);
6655 // FIXME: Check that the base has a usable destructor! Sink this into
6656 // shouldDeleteForClassSubobject.
6657 if (BaseCtor->isDeleted() && Diagnose) {
6658 S.Diag(Base->getLocStart(),
6659 diag::note_deleted_special_member_class_subobject)
6660 << getEffectiveCSM() << MD->getParent() << /*IsField*/false
6661 << Base->getType() << /*Deleted*/1 << /*IsDtorCallInCtor*/false;
6662 S.NoteDeletedFunction(BaseCtor);
6664 return BaseCtor->isDeleted();
6666 return shouldDeleteForClassSubobject(BaseClass, Base, 0);
6669 /// Check whether we should delete a special member function due to the class
6670 /// having a particular non-static data member.
6671 bool SpecialMemberDeletionInfo::shouldDeleteForField(FieldDecl *FD) {
6672 QualType FieldType = S.Context.getBaseElementType(FD->getType());
6673 CXXRecordDecl *FieldRecord = FieldType->getAsCXXRecordDecl();
6675 if (CSM == Sema::CXXDefaultConstructor) {
6676 // For a default constructor, all references must be initialized in-class
6677 // and, if a union, it must have a non-const member.
6678 if (FieldType->isReferenceType() && !FD->hasInClassInitializer()) {
6680 S.Diag(FD->getLocation(), diag::note_deleted_default_ctor_uninit_field)
6681 << !!ICI << MD->getParent() << FD << FieldType << /*Reference*/0;
6684 // C++11 [class.ctor]p5: any non-variant non-static data member of
6685 // const-qualified type (or array thereof) with no
6686 // brace-or-equal-initializer does not have a user-provided default
6688 if (!inUnion() && FieldType.isConstQualified() &&
6689 !FD->hasInClassInitializer() &&
6690 (!FieldRecord || !FieldRecord->hasUserProvidedDefaultConstructor())) {
6692 S.Diag(FD->getLocation(), diag::note_deleted_default_ctor_uninit_field)
6693 << !!ICI << MD->getParent() << FD << FD->getType() << /*Const*/1;
6697 if (inUnion() && !FieldType.isConstQualified())
6698 AllFieldsAreConst = false;
6699 } else if (CSM == Sema::CXXCopyConstructor) {
6700 // For a copy constructor, data members must not be of rvalue reference
6702 if (FieldType->isRValueReferenceType()) {
6704 S.Diag(FD->getLocation(), diag::note_deleted_copy_ctor_rvalue_reference)
6705 << MD->getParent() << FD << FieldType;
6708 } else if (IsAssignment) {
6709 // For an assignment operator, data members must not be of reference type.
6710 if (FieldType->isReferenceType()) {
6712 S.Diag(FD->getLocation(), diag::note_deleted_assign_field)
6713 << isMove() << MD->getParent() << FD << FieldType << /*Reference*/0;
6716 if (!FieldRecord && FieldType.isConstQualified()) {
6717 // C++11 [class.copy]p23:
6718 // -- a non-static data member of const non-class type (or array thereof)
6720 S.Diag(FD->getLocation(), diag::note_deleted_assign_field)
6721 << isMove() << MD->getParent() << FD << FD->getType() << /*Const*/1;
6727 // Some additional restrictions exist on the variant members.
6728 if (!inUnion() && FieldRecord->isUnion() &&
6729 FieldRecord->isAnonymousStructOrUnion()) {
6730 bool AllVariantFieldsAreConst = true;
6732 // FIXME: Handle anonymous unions declared within anonymous unions.
6733 for (auto *UI : FieldRecord->fields()) {
6734 QualType UnionFieldType = S.Context.getBaseElementType(UI->getType());
6736 if (!UnionFieldType.isConstQualified())
6737 AllVariantFieldsAreConst = false;
6739 CXXRecordDecl *UnionFieldRecord = UnionFieldType->getAsCXXRecordDecl();
6740 if (UnionFieldRecord &&
6741 shouldDeleteForClassSubobject(UnionFieldRecord, UI,
6742 UnionFieldType.getCVRQualifiers()))
6746 // At least one member in each anonymous union must be non-const
6747 if (CSM == Sema::CXXDefaultConstructor && AllVariantFieldsAreConst &&
6748 !FieldRecord->field_empty()) {
6750 S.Diag(FieldRecord->getLocation(),
6751 diag::note_deleted_default_ctor_all_const)
6752 << !!ICI << MD->getParent() << /*anonymous union*/1;
6756 // Don't check the implicit member of the anonymous union type.
6757 // This is technically non-conformant, but sanity demands it.
6761 if (shouldDeleteForClassSubobject(FieldRecord, FD,
6762 FieldType.getCVRQualifiers()))
6769 /// C++11 [class.ctor] p5:
6770 /// A defaulted default constructor for a class X is defined as deleted if
6771 /// X is a union and all of its variant members are of const-qualified type.
6772 bool SpecialMemberDeletionInfo::shouldDeleteForAllConstMembers() {
6773 // This is a silly definition, because it gives an empty union a deleted
6774 // default constructor. Don't do that.
6775 if (CSM == Sema::CXXDefaultConstructor && inUnion() && AllFieldsAreConst) {
6776 bool AnyFields = false;
6777 for (auto *F : MD->getParent()->fields())
6778 if ((AnyFields = !F->isUnnamedBitfield()))
6783 S.Diag(MD->getParent()->getLocation(),
6784 diag::note_deleted_default_ctor_all_const)
6785 << !!ICI << MD->getParent() << /*not anonymous union*/0;
6791 /// Determine whether a defaulted special member function should be defined as
6792 /// deleted, as specified in C++11 [class.ctor]p5, C++11 [class.copy]p11,
6793 /// C++11 [class.copy]p23, and C++11 [class.dtor]p5.
6794 bool Sema::ShouldDeleteSpecialMember(CXXMethodDecl *MD, CXXSpecialMember CSM,
6795 InheritedConstructorInfo *ICI,
6797 if (MD->isInvalidDecl())
6799 CXXRecordDecl *RD = MD->getParent();
6800 assert(!RD->isDependentType() && "do deletion after instantiation");
6801 if (!LangOpts.CPlusPlus11 || RD->isInvalidDecl())
6804 // C++11 [expr.lambda.prim]p19:
6805 // The closure type associated with a lambda-expression has a
6806 // deleted (8.4.3) default constructor and a deleted copy
6807 // assignment operator.
6808 if (RD->isLambda() &&
6809 (CSM == CXXDefaultConstructor || CSM == CXXCopyAssignment)) {
6811 Diag(RD->getLocation(), diag::note_lambda_decl);
6815 // For an anonymous struct or union, the copy and assignment special members
6816 // will never be used, so skip the check. For an anonymous union declared at
6817 // namespace scope, the constructor and destructor are used.
6818 if (CSM != CXXDefaultConstructor && CSM != CXXDestructor &&
6819 RD->isAnonymousStructOrUnion())
6822 // C++11 [class.copy]p7, p18:
6823 // If the class definition declares a move constructor or move assignment
6824 // operator, an implicitly declared copy constructor or copy assignment
6825 // operator is defined as deleted.
6826 if (MD->isImplicit() &&
6827 (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment)) {
6828 CXXMethodDecl *UserDeclaredMove = nullptr;
6830 // In Microsoft mode up to MSVC 2013, a user-declared move only causes the
6831 // deletion of the corresponding copy operation, not both copy operations.
6832 // MSVC 2015 has adopted the standards conforming behavior.
6833 bool DeletesOnlyMatchingCopy =
6834 getLangOpts().MSVCCompat &&
6835 !getLangOpts().isCompatibleWithMSVC(LangOptions::MSVC2015);
6837 if (RD->hasUserDeclaredMoveConstructor() &&
6838 (!DeletesOnlyMatchingCopy || CSM == CXXCopyConstructor)) {
6839 if (!Diagnose) return true;
6841 // Find any user-declared move constructor.
6842 for (auto *I : RD->ctors()) {
6843 if (I->isMoveConstructor()) {
6844 UserDeclaredMove = I;
6848 assert(UserDeclaredMove);
6849 } else if (RD->hasUserDeclaredMoveAssignment() &&
6850 (!DeletesOnlyMatchingCopy || CSM == CXXCopyAssignment)) {
6851 if (!Diagnose) return true;
6853 // Find any user-declared move assignment operator.
6854 for (auto *I : RD->methods()) {
6855 if (I->isMoveAssignmentOperator()) {
6856 UserDeclaredMove = I;
6860 assert(UserDeclaredMove);
6863 if (UserDeclaredMove) {
6864 Diag(UserDeclaredMove->getLocation(),
6865 diag::note_deleted_copy_user_declared_move)
6866 << (CSM == CXXCopyAssignment) << RD
6867 << UserDeclaredMove->isMoveAssignmentOperator();
6872 // Do access control from the special member function
6873 ContextRAII MethodContext(*this, MD);
6875 // C++11 [class.dtor]p5:
6876 // -- for a virtual destructor, lookup of the non-array deallocation function
6877 // results in an ambiguity or in a function that is deleted or inaccessible
6878 if (CSM == CXXDestructor && MD->isVirtual()) {
6879 FunctionDecl *OperatorDelete = nullptr;
6880 DeclarationName Name =
6881 Context.DeclarationNames.getCXXOperatorName(OO_Delete);
6882 if (FindDeallocationFunction(MD->getLocation(), MD->getParent(), Name,
6883 OperatorDelete, /*Diagnose*/false)) {
6885 Diag(RD->getLocation(), diag::note_deleted_dtor_no_operator_delete);
6890 SpecialMemberDeletionInfo SMI(*this, MD, CSM, ICI, Diagnose);
6892 // Per DR1611, do not consider virtual bases of constructors of abstract
6893 // classes, since we are not going to construct them.
6894 // Per DR1658, do not consider virtual bases of destructors of abstract
6896 // Per DR2180, for assignment operators we only assign (and thus only
6897 // consider) direct bases.
6898 if (SMI.visit(SMI.IsAssignment ? SMI.VisitDirectBases
6899 : SMI.VisitPotentiallyConstructedBases))
6902 if (SMI.shouldDeleteForAllConstMembers())
6905 if (getLangOpts().CUDA) {
6906 // We should delete the special member in CUDA mode if target inference
6908 return inferCUDATargetForImplicitSpecialMember(RD, CSM, MD, SMI.ConstArg,
6915 /// Perform lookup for a special member of the specified kind, and determine
6916 /// whether it is trivial. If the triviality can be determined without the
6917 /// lookup, skip it. This is intended for use when determining whether a
6918 /// special member of a containing object is trivial, and thus does not ever
6919 /// perform overload resolution for default constructors.
6921 /// If \p Selected is not \c NULL, \c *Selected will be filled in with the
6922 /// member that was most likely to be intended to be trivial, if any.
6923 static bool findTrivialSpecialMember(Sema &S, CXXRecordDecl *RD,
6924 Sema::CXXSpecialMember CSM, unsigned Quals,
6925 bool ConstRHS, CXXMethodDecl **Selected) {
6927 *Selected = nullptr;
6930 case Sema::CXXInvalid:
6931 llvm_unreachable("not a special member");
6933 case Sema::CXXDefaultConstructor:
6934 // C++11 [class.ctor]p5:
6935 // A default constructor is trivial if:
6936 // - all the [direct subobjects] have trivial default constructors
6938 // Note, no overload resolution is performed in this case.
6939 if (RD->hasTrivialDefaultConstructor())
6943 // If there's a default constructor which could have been trivial, dig it
6944 // out. Otherwise, if there's any user-provided default constructor, point
6945 // to that as an example of why there's not a trivial one.
6946 CXXConstructorDecl *DefCtor = nullptr;
6947 if (RD->needsImplicitDefaultConstructor())
6948 S.DeclareImplicitDefaultConstructor(RD);
6949 for (auto *CI : RD->ctors()) {
6950 if (!CI->isDefaultConstructor())
6953 if (!DefCtor->isUserProvided())
6957 *Selected = DefCtor;
6962 case Sema::CXXDestructor:
6963 // C++11 [class.dtor]p5:
6964 // A destructor is trivial if:
6965 // - all the direct [subobjects] have trivial destructors
6966 if (RD->hasTrivialDestructor())
6970 if (RD->needsImplicitDestructor())
6971 S.DeclareImplicitDestructor(RD);
6972 *Selected = RD->getDestructor();
6977 case Sema::CXXCopyConstructor:
6978 // C++11 [class.copy]p12:
6979 // A copy constructor is trivial if:
6980 // - the constructor selected to copy each direct [subobject] is trivial
6981 if (RD->hasTrivialCopyConstructor()) {
6982 if (Quals == Qualifiers::Const)
6983 // We must either select the trivial copy constructor or reach an
6984 // ambiguity; no need to actually perform overload resolution.
6986 } else if (!Selected) {
6989 // In C++98, we are not supposed to perform overload resolution here, but we
6990 // treat that as a language defect, as suggested on cxx-abi-dev, to treat
6991 // cases like B as having a non-trivial copy constructor:
6992 // struct A { template<typename T> A(T&); };
6993 // struct B { mutable A a; };
6994 goto NeedOverloadResolution;
6996 case Sema::CXXCopyAssignment:
6997 // C++11 [class.copy]p25:
6998 // A copy assignment operator is trivial if:
6999 // - the assignment operator selected to copy each direct [subobject] is
7001 if (RD->hasTrivialCopyAssignment()) {
7002 if (Quals == Qualifiers::Const)
7004 } else if (!Selected) {
7007 // In C++98, we are not supposed to perform overload resolution here, but we
7008 // treat that as a language defect.
7009 goto NeedOverloadResolution;
7011 case Sema::CXXMoveConstructor:
7012 case Sema::CXXMoveAssignment:
7013 NeedOverloadResolution:
7014 Sema::SpecialMemberOverloadResult SMOR =
7015 lookupCallFromSpecialMember(S, RD, CSM, Quals, ConstRHS);
7017 // The standard doesn't describe how to behave if the lookup is ambiguous.
7018 // We treat it as not making the member non-trivial, just like the standard
7019 // mandates for the default constructor. This should rarely matter, because
7020 // the member will also be deleted.
7021 if (SMOR.getKind() == Sema::SpecialMemberOverloadResult::Ambiguous)
7024 if (!SMOR.getMethod()) {
7025 assert(SMOR.getKind() ==
7026 Sema::SpecialMemberOverloadResult::NoMemberOrDeleted);
7030 // We deliberately don't check if we found a deleted special member. We're
7033 *Selected = SMOR.getMethod();
7034 return SMOR.getMethod()->isTrivial();
7037 llvm_unreachable("unknown special method kind");
7040 static CXXConstructorDecl *findUserDeclaredCtor(CXXRecordDecl *RD) {
7041 for (auto *CI : RD->ctors())
7042 if (!CI->isImplicit())
7045 // Look for constructor templates.
7046 typedef CXXRecordDecl::specific_decl_iterator<FunctionTemplateDecl> tmpl_iter;
7047 for (tmpl_iter TI(RD->decls_begin()), TE(RD->decls_end()); TI != TE; ++TI) {
7048 if (CXXConstructorDecl *CD =
7049 dyn_cast<CXXConstructorDecl>(TI->getTemplatedDecl()))
7056 /// The kind of subobject we are checking for triviality. The values of this
7057 /// enumeration are used in diagnostics.
7058 enum TrivialSubobjectKind {
7059 /// The subobject is a base class.
7061 /// The subobject is a non-static data member.
7063 /// The object is actually the complete object.
7067 /// Check whether the special member selected for a given type would be trivial.
7068 static bool checkTrivialSubobjectCall(Sema &S, SourceLocation SubobjLoc,
7069 QualType SubType, bool ConstRHS,
7070 Sema::CXXSpecialMember CSM,
7071 TrivialSubobjectKind Kind,
7073 CXXRecordDecl *SubRD = SubType->getAsCXXRecordDecl();
7077 CXXMethodDecl *Selected;
7078 if (findTrivialSpecialMember(S, SubRD, CSM, SubType.getCVRQualifiers(),
7079 ConstRHS, Diagnose ? &Selected : nullptr))
7086 if (!Selected && CSM == Sema::CXXDefaultConstructor) {
7087 S.Diag(SubobjLoc, diag::note_nontrivial_no_def_ctor)
7088 << Kind << SubType.getUnqualifiedType();
7089 if (CXXConstructorDecl *CD = findUserDeclaredCtor(SubRD))
7090 S.Diag(CD->getLocation(), diag::note_user_declared_ctor);
7091 } else if (!Selected)
7092 S.Diag(SubobjLoc, diag::note_nontrivial_no_copy)
7093 << Kind << SubType.getUnqualifiedType() << CSM << SubType;
7094 else if (Selected->isUserProvided()) {
7095 if (Kind == TSK_CompleteObject)
7096 S.Diag(Selected->getLocation(), diag::note_nontrivial_user_provided)
7097 << Kind << SubType.getUnqualifiedType() << CSM;
7099 S.Diag(SubobjLoc, diag::note_nontrivial_user_provided)
7100 << Kind << SubType.getUnqualifiedType() << CSM;
7101 S.Diag(Selected->getLocation(), diag::note_declared_at);
7104 if (Kind != TSK_CompleteObject)
7105 S.Diag(SubobjLoc, diag::note_nontrivial_subobject)
7106 << Kind << SubType.getUnqualifiedType() << CSM;
7108 // Explain why the defaulted or deleted special member isn't trivial.
7109 S.SpecialMemberIsTrivial(Selected, CSM, Diagnose);
7116 /// Check whether the members of a class type allow a special member to be
7118 static bool checkTrivialClassMembers(Sema &S, CXXRecordDecl *RD,
7119 Sema::CXXSpecialMember CSM,
7120 bool ConstArg, bool Diagnose) {
7121 for (const auto *FI : RD->fields()) {
7122 if (FI->isInvalidDecl() || FI->isUnnamedBitfield())
7125 QualType FieldType = S.Context.getBaseElementType(FI->getType());
7127 // Pretend anonymous struct or union members are members of this class.
7128 if (FI->isAnonymousStructOrUnion()) {
7129 if (!checkTrivialClassMembers(S, FieldType->getAsCXXRecordDecl(),
7130 CSM, ConstArg, Diagnose))
7135 // C++11 [class.ctor]p5:
7136 // A default constructor is trivial if [...]
7137 // -- no non-static data member of its class has a
7138 // brace-or-equal-initializer
7139 if (CSM == Sema::CXXDefaultConstructor && FI->hasInClassInitializer()) {
7141 S.Diag(FI->getLocation(), diag::note_nontrivial_in_class_init) << FI;
7145 // Objective C ARC 4.3.5:
7146 // [...] nontrivally ownership-qualified types are [...] not trivially
7147 // default constructible, copy constructible, move constructible, copy
7148 // assignable, move assignable, or destructible [...]
7149 if (FieldType.hasNonTrivialObjCLifetime()) {
7151 S.Diag(FI->getLocation(), diag::note_nontrivial_objc_ownership)
7152 << RD << FieldType.getObjCLifetime();
7156 bool ConstRHS = ConstArg && !FI->isMutable();
7157 if (!checkTrivialSubobjectCall(S, FI->getLocation(), FieldType, ConstRHS,
7158 CSM, TSK_Field, Diagnose))
7165 /// Diagnose why the specified class does not have a trivial special member of
7167 void Sema::DiagnoseNontrivial(const CXXRecordDecl *RD, CXXSpecialMember CSM) {
7168 QualType Ty = Context.getRecordType(RD);
7170 bool ConstArg = (CSM == CXXCopyConstructor || CSM == CXXCopyAssignment);
7171 checkTrivialSubobjectCall(*this, RD->getLocation(), Ty, ConstArg, CSM,
7172 TSK_CompleteObject, /*Diagnose*/true);
7175 /// Determine whether a defaulted or deleted special member function is trivial,
7176 /// as specified in C++11 [class.ctor]p5, C++11 [class.copy]p12,
7177 /// C++11 [class.copy]p25, and C++11 [class.dtor]p5.
7178 bool Sema::SpecialMemberIsTrivial(CXXMethodDecl *MD, CXXSpecialMember CSM,
7180 assert(!MD->isUserProvided() && CSM != CXXInvalid && "not special enough");
7182 CXXRecordDecl *RD = MD->getParent();
7184 bool ConstArg = false;
7186 // C++11 [class.copy]p12, p25: [DR1593]
7187 // A [special member] is trivial if [...] its parameter-type-list is
7188 // equivalent to the parameter-type-list of an implicit declaration [...]
7190 case CXXDefaultConstructor:
7192 // Trivial default constructors and destructors cannot have parameters.
7195 case CXXCopyConstructor:
7196 case CXXCopyAssignment: {
7197 // Trivial copy operations always have const, non-volatile parameter types.
7199 const ParmVarDecl *Param0 = MD->getParamDecl(0);
7200 const ReferenceType *RT = Param0->getType()->getAs<ReferenceType>();
7201 if (!RT || RT->getPointeeType().getCVRQualifiers() != Qualifiers::Const) {
7203 Diag(Param0->getLocation(), diag::note_nontrivial_param_type)
7204 << Param0->getSourceRange() << Param0->getType()
7205 << Context.getLValueReferenceType(
7206 Context.getRecordType(RD).withConst());
7212 case CXXMoveConstructor:
7213 case CXXMoveAssignment: {
7214 // Trivial move operations always have non-cv-qualified parameters.
7215 const ParmVarDecl *Param0 = MD->getParamDecl(0);
7216 const RValueReferenceType *RT =
7217 Param0->getType()->getAs<RValueReferenceType>();
7218 if (!RT || RT->getPointeeType().getCVRQualifiers()) {
7220 Diag(Param0->getLocation(), diag::note_nontrivial_param_type)
7221 << Param0->getSourceRange() << Param0->getType()
7222 << Context.getRValueReferenceType(Context.getRecordType(RD));
7229 llvm_unreachable("not a special member");
7232 if (MD->getMinRequiredArguments() < MD->getNumParams()) {
7234 Diag(MD->getParamDecl(MD->getMinRequiredArguments())->getLocation(),
7235 diag::note_nontrivial_default_arg)
7236 << MD->getParamDecl(MD->getMinRequiredArguments())->getSourceRange();
7239 if (MD->isVariadic()) {
7241 Diag(MD->getLocation(), diag::note_nontrivial_variadic);
7245 // C++11 [class.ctor]p5, C++11 [class.dtor]p5:
7246 // A copy/move [constructor or assignment operator] is trivial if
7247 // -- the [member] selected to copy/move each direct base class subobject
7250 // C++11 [class.copy]p12, C++11 [class.copy]p25:
7251 // A [default constructor or destructor] is trivial if
7252 // -- all the direct base classes have trivial [default constructors or
7254 for (const auto &BI : RD->bases())
7255 if (!checkTrivialSubobjectCall(*this, BI.getLocStart(), BI.getType(),
7256 ConstArg, CSM, TSK_BaseClass, Diagnose))
7259 // C++11 [class.ctor]p5, C++11 [class.dtor]p5:
7260 // A copy/move [constructor or assignment operator] for a class X is
7262 // -- for each non-static data member of X that is of class type (or array
7263 // thereof), the constructor selected to copy/move that member is
7266 // C++11 [class.copy]p12, C++11 [class.copy]p25:
7267 // A [default constructor or destructor] is trivial if
7268 // -- for all of the non-static data members of its class that are of class
7269 // type (or array thereof), each such class has a trivial [default
7270 // constructor or destructor]
7271 if (!checkTrivialClassMembers(*this, RD, CSM, ConstArg, Diagnose))
7274 // C++11 [class.dtor]p5:
7275 // A destructor is trivial if [...]
7276 // -- the destructor is not virtual
7277 if (CSM == CXXDestructor && MD->isVirtual()) {
7279 Diag(MD->getLocation(), diag::note_nontrivial_virtual_dtor) << RD;
7283 // C++11 [class.ctor]p5, C++11 [class.copy]p12, C++11 [class.copy]p25:
7284 // A [special member] for class X is trivial if [...]
7285 // -- class X has no virtual functions and no virtual base classes
7286 if (CSM != CXXDestructor && MD->getParent()->isDynamicClass()) {
7290 if (RD->getNumVBases()) {
7291 // Check for virtual bases. We already know that the corresponding
7292 // member in all bases is trivial, so vbases must all be direct.
7293 CXXBaseSpecifier &BS = *RD->vbases_begin();
7294 assert(BS.isVirtual());
7295 Diag(BS.getLocStart(), diag::note_nontrivial_has_virtual) << RD << 1;
7299 // Must have a virtual method.
7300 for (const auto *MI : RD->methods()) {
7301 if (MI->isVirtual()) {
7302 SourceLocation MLoc = MI->getLocStart();
7303 Diag(MLoc, diag::note_nontrivial_has_virtual) << RD << 0;
7308 llvm_unreachable("dynamic class with no vbases and no virtual functions");
7311 // Looks like it's trivial!
7316 struct FindHiddenVirtualMethod {
7318 CXXMethodDecl *Method;
7319 llvm::SmallPtrSet<const CXXMethodDecl *, 8> OverridenAndUsingBaseMethods;
7320 SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
7323 /// Check whether any most overriden method from MD in Methods
7324 static bool CheckMostOverridenMethods(
7325 const CXXMethodDecl *MD,
7326 const llvm::SmallPtrSetImpl<const CXXMethodDecl *> &Methods) {
7327 if (MD->size_overridden_methods() == 0)
7328 return Methods.count(MD->getCanonicalDecl());
7329 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
7330 E = MD->end_overridden_methods();
7332 if (CheckMostOverridenMethods(*I, Methods))
7338 /// Member lookup function that determines whether a given C++
7339 /// method overloads virtual methods in a base class without overriding any,
7340 /// to be used with CXXRecordDecl::lookupInBases().
7341 bool operator()(const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
7342 RecordDecl *BaseRecord =
7343 Specifier->getType()->getAs<RecordType>()->getDecl();
7345 DeclarationName Name = Method->getDeclName();
7346 assert(Name.getNameKind() == DeclarationName::Identifier);
7348 bool foundSameNameMethod = false;
7349 SmallVector<CXXMethodDecl *, 8> overloadedMethods;
7350 for (Path.Decls = BaseRecord->lookup(Name); !Path.Decls.empty();
7351 Path.Decls = Path.Decls.slice(1)) {
7352 NamedDecl *D = Path.Decls.front();
7353 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(D)) {
7354 MD = MD->getCanonicalDecl();
7355 foundSameNameMethod = true;
7356 // Interested only in hidden virtual methods.
7357 if (!MD->isVirtual())
7359 // If the method we are checking overrides a method from its base
7360 // don't warn about the other overloaded methods. Clang deviates from
7361 // GCC by only diagnosing overloads of inherited virtual functions that
7362 // do not override any other virtual functions in the base. GCC's
7363 // -Woverloaded-virtual diagnoses any derived function hiding a virtual
7364 // function from a base class. These cases may be better served by a
7365 // warning (not specific to virtual functions) on call sites when the
7366 // call would select a different function from the base class, were it
7368 // See FIXME in test/SemaCXX/warn-overload-virtual.cpp for an example.
7369 if (!S->IsOverload(Method, MD, false))
7371 // Collect the overload only if its hidden.
7372 if (!CheckMostOverridenMethods(MD, OverridenAndUsingBaseMethods))
7373 overloadedMethods.push_back(MD);
7377 if (foundSameNameMethod)
7378 OverloadedMethods.append(overloadedMethods.begin(),
7379 overloadedMethods.end());
7380 return foundSameNameMethod;
7383 } // end anonymous namespace
7385 /// \brief Add the most overriden methods from MD to Methods
7386 static void AddMostOverridenMethods(const CXXMethodDecl *MD,
7387 llvm::SmallPtrSetImpl<const CXXMethodDecl *>& Methods) {
7388 if (MD->size_overridden_methods() == 0)
7389 Methods.insert(MD->getCanonicalDecl());
7390 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
7391 E = MD->end_overridden_methods();
7393 AddMostOverridenMethods(*I, Methods);
7396 /// \brief Check if a method overloads virtual methods in a base class without
7398 void Sema::FindHiddenVirtualMethods(CXXMethodDecl *MD,
7399 SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods) {
7400 if (!MD->getDeclName().isIdentifier())
7403 CXXBasePaths Paths(/*FindAmbiguities=*/true, // true to look in all bases.
7404 /*bool RecordPaths=*/false,
7405 /*bool DetectVirtual=*/false);
7406 FindHiddenVirtualMethod FHVM;
7410 // Keep the base methods that were overriden or introduced in the subclass
7411 // by 'using' in a set. A base method not in this set is hidden.
7412 CXXRecordDecl *DC = MD->getParent();
7413 DeclContext::lookup_result R = DC->lookup(MD->getDeclName());
7414 for (DeclContext::lookup_iterator I = R.begin(), E = R.end(); I != E; ++I) {
7416 if (UsingShadowDecl *shad = dyn_cast<UsingShadowDecl>(*I))
7417 ND = shad->getTargetDecl();
7418 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(ND))
7419 AddMostOverridenMethods(MD, FHVM.OverridenAndUsingBaseMethods);
7422 if (DC->lookupInBases(FHVM, Paths))
7423 OverloadedMethods = FHVM.OverloadedMethods;
7426 void Sema::NoteHiddenVirtualMethods(CXXMethodDecl *MD,
7427 SmallVectorImpl<CXXMethodDecl*> &OverloadedMethods) {
7428 for (unsigned i = 0, e = OverloadedMethods.size(); i != e; ++i) {
7429 CXXMethodDecl *overloadedMD = OverloadedMethods[i];
7430 PartialDiagnostic PD = PDiag(
7431 diag::note_hidden_overloaded_virtual_declared_here) << overloadedMD;
7432 HandleFunctionTypeMismatch(PD, MD->getType(), overloadedMD->getType());
7433 Diag(overloadedMD->getLocation(), PD);
7437 /// \brief Diagnose methods which overload virtual methods in a base class
7438 /// without overriding any.
7439 void Sema::DiagnoseHiddenVirtualMethods(CXXMethodDecl *MD) {
7440 if (MD->isInvalidDecl())
7443 if (Diags.isIgnored(diag::warn_overloaded_virtual, MD->getLocation()))
7446 SmallVector<CXXMethodDecl *, 8> OverloadedMethods;
7447 FindHiddenVirtualMethods(MD, OverloadedMethods);
7448 if (!OverloadedMethods.empty()) {
7449 Diag(MD->getLocation(), diag::warn_overloaded_virtual)
7450 << MD << (OverloadedMethods.size() > 1);
7452 NoteHiddenVirtualMethods(MD, OverloadedMethods);
7456 void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc,
7458 SourceLocation LBrac,
7459 SourceLocation RBrac,
7460 AttributeList *AttrList) {
7464 AdjustDeclIfTemplate(TagDecl);
7466 for (const AttributeList* l = AttrList; l; l = l->getNext()) {
7467 if (l->getKind() != AttributeList::AT_Visibility)
7470 Diag(l->getLoc(), diag::warn_attribute_after_definition_ignored) <<
7474 ActOnFields(S, RLoc, TagDecl, llvm::makeArrayRef(
7475 // strict aliasing violation!
7476 reinterpret_cast<Decl**>(FieldCollector->getCurFields()),
7477 FieldCollector->getCurNumFields()), LBrac, RBrac, AttrList);
7479 CheckCompletedCXXClass(
7480 dyn_cast_or_null<CXXRecordDecl>(TagDecl));
7483 /// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared
7484 /// special functions, such as the default constructor, copy
7485 /// constructor, or destructor, to the given C++ class (C++
7486 /// [special]p1). This routine can only be executed just before the
7487 /// definition of the class is complete.
7488 void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) {
7489 if (ClassDecl->needsImplicitDefaultConstructor()) {
7490 ++ASTContext::NumImplicitDefaultConstructors;
7492 if (ClassDecl->hasInheritedConstructor())
7493 DeclareImplicitDefaultConstructor(ClassDecl);
7496 if (ClassDecl->needsImplicitCopyConstructor()) {
7497 ++ASTContext::NumImplicitCopyConstructors;
7499 // If the properties or semantics of the copy constructor couldn't be
7500 // determined while the class was being declared, force a declaration
7502 if (ClassDecl->needsOverloadResolutionForCopyConstructor() ||
7503 ClassDecl->hasInheritedConstructor())
7504 DeclareImplicitCopyConstructor(ClassDecl);
7505 // For the MS ABI we need to know whether the copy ctor is deleted. A
7506 // prerequisite for deleting the implicit copy ctor is that the class has a
7507 // move ctor or move assignment that is either user-declared or whose
7508 // semantics are inherited from a subobject. FIXME: We should provide a more
7509 // direct way for CodeGen to ask whether the constructor was deleted.
7510 else if (Context.getTargetInfo().getCXXABI().isMicrosoft() &&
7511 (ClassDecl->hasUserDeclaredMoveConstructor() ||
7512 ClassDecl->needsOverloadResolutionForMoveConstructor() ||
7513 ClassDecl->hasUserDeclaredMoveAssignment() ||
7514 ClassDecl->needsOverloadResolutionForMoveAssignment()))
7515 DeclareImplicitCopyConstructor(ClassDecl);
7518 if (getLangOpts().CPlusPlus11 && ClassDecl->needsImplicitMoveConstructor()) {
7519 ++ASTContext::NumImplicitMoveConstructors;
7521 if (ClassDecl->needsOverloadResolutionForMoveConstructor() ||
7522 ClassDecl->hasInheritedConstructor())
7523 DeclareImplicitMoveConstructor(ClassDecl);
7526 if (ClassDecl->needsImplicitCopyAssignment()) {
7527 ++ASTContext::NumImplicitCopyAssignmentOperators;
7529 // If we have a dynamic class, then the copy assignment operator may be
7530 // virtual, so we have to declare it immediately. This ensures that, e.g.,
7531 // it shows up in the right place in the vtable and that we diagnose
7532 // problems with the implicit exception specification.
7533 if (ClassDecl->isDynamicClass() ||
7534 ClassDecl->needsOverloadResolutionForCopyAssignment() ||
7535 ClassDecl->hasInheritedAssignment())
7536 DeclareImplicitCopyAssignment(ClassDecl);
7539 if (getLangOpts().CPlusPlus11 && ClassDecl->needsImplicitMoveAssignment()) {
7540 ++ASTContext::NumImplicitMoveAssignmentOperators;
7542 // Likewise for the move assignment operator.
7543 if (ClassDecl->isDynamicClass() ||
7544 ClassDecl->needsOverloadResolutionForMoveAssignment() ||
7545 ClassDecl->hasInheritedAssignment())
7546 DeclareImplicitMoveAssignment(ClassDecl);
7549 if (ClassDecl->needsImplicitDestructor()) {
7550 ++ASTContext::NumImplicitDestructors;
7552 // If we have a dynamic class, then the destructor may be virtual, so we
7553 // have to declare the destructor immediately. This ensures that, e.g., it
7554 // shows up in the right place in the vtable and that we diagnose problems
7555 // with the implicit exception specification.
7556 if (ClassDecl->isDynamicClass() ||
7557 ClassDecl->needsOverloadResolutionForDestructor())
7558 DeclareImplicitDestructor(ClassDecl);
7562 unsigned Sema::ActOnReenterTemplateScope(Scope *S, Decl *D) {
7566 // The order of template parameters is not important here. All names
7567 // get added to the same scope.
7568 SmallVector<TemplateParameterList *, 4> ParameterLists;
7570 if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
7571 D = TD->getTemplatedDecl();
7573 if (auto *PSD = dyn_cast<ClassTemplatePartialSpecializationDecl>(D))
7574 ParameterLists.push_back(PSD->getTemplateParameters());
7576 if (DeclaratorDecl *DD = dyn_cast<DeclaratorDecl>(D)) {
7577 for (unsigned i = 0; i < DD->getNumTemplateParameterLists(); ++i)
7578 ParameterLists.push_back(DD->getTemplateParameterList(i));
7580 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
7581 if (FunctionTemplateDecl *FTD = FD->getDescribedFunctionTemplate())
7582 ParameterLists.push_back(FTD->getTemplateParameters());
7586 if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
7587 for (unsigned i = 0; i < TD->getNumTemplateParameterLists(); ++i)
7588 ParameterLists.push_back(TD->getTemplateParameterList(i));
7590 if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(TD)) {
7591 if (ClassTemplateDecl *CTD = RD->getDescribedClassTemplate())
7592 ParameterLists.push_back(CTD->getTemplateParameters());
7597 for (TemplateParameterList *Params : ParameterLists) {
7598 if (Params->size() > 0)
7599 // Ignore explicit specializations; they don't contribute to the template
7602 for (NamedDecl *Param : *Params) {
7603 if (Param->getDeclName()) {
7605 IdResolver.AddDecl(Param);
7613 void Sema::ActOnStartDelayedMemberDeclarations(Scope *S, Decl *RecordD) {
7614 if (!RecordD) return;
7615 AdjustDeclIfTemplate(RecordD);
7616 CXXRecordDecl *Record = cast<CXXRecordDecl>(RecordD);
7617 PushDeclContext(S, Record);
7620 void Sema::ActOnFinishDelayedMemberDeclarations(Scope *S, Decl *RecordD) {
7621 if (!RecordD) return;
7625 /// This is used to implement the constant expression evaluation part of the
7626 /// attribute enable_if extension. There is nothing in standard C++ which would
7627 /// require reentering parameters.
7628 void Sema::ActOnReenterCXXMethodParameter(Scope *S, ParmVarDecl *Param) {
7633 if (Param->getDeclName())
7634 IdResolver.AddDecl(Param);
7637 /// ActOnStartDelayedCXXMethodDeclaration - We have completed
7638 /// parsing a top-level (non-nested) C++ class, and we are now
7639 /// parsing those parts of the given Method declaration that could
7640 /// not be parsed earlier (C++ [class.mem]p2), such as default
7641 /// arguments. This action should enter the scope of the given
7642 /// Method declaration as if we had just parsed the qualified method
7643 /// name. However, it should not bring the parameters into scope;
7644 /// that will be performed by ActOnDelayedCXXMethodParameter.
7645 void Sema::ActOnStartDelayedCXXMethodDeclaration(Scope *S, Decl *MethodD) {
7648 /// ActOnDelayedCXXMethodParameter - We've already started a delayed
7649 /// C++ method declaration. We're (re-)introducing the given
7650 /// function parameter into scope for use in parsing later parts of
7651 /// the method declaration. For example, we could see an
7652 /// ActOnParamDefaultArgument event for this parameter.
7653 void Sema::ActOnDelayedCXXMethodParameter(Scope *S, Decl *ParamD) {
7657 ParmVarDecl *Param = cast<ParmVarDecl>(ParamD);
7659 // If this parameter has an unparsed default argument, clear it out
7660 // to make way for the parsed default argument.
7661 if (Param->hasUnparsedDefaultArg())
7662 Param->setDefaultArg(nullptr);
7665 if (Param->getDeclName())
7666 IdResolver.AddDecl(Param);
7669 /// ActOnFinishDelayedCXXMethodDeclaration - We have finished
7670 /// processing the delayed method declaration for Method. The method
7671 /// declaration is now considered finished. There may be a separate
7672 /// ActOnStartOfFunctionDef action later (not necessarily
7673 /// immediately!) for this method, if it was also defined inside the
7675 void Sema::ActOnFinishDelayedCXXMethodDeclaration(Scope *S, Decl *MethodD) {
7679 AdjustDeclIfTemplate(MethodD);
7681 FunctionDecl *Method = cast<FunctionDecl>(MethodD);
7683 // Now that we have our default arguments, check the constructor
7684 // again. It could produce additional diagnostics or affect whether
7685 // the class has implicitly-declared destructors, among other
7687 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Method))
7688 CheckConstructor(Constructor);
7690 // Check the default arguments, which we may have added.
7691 if (!Method->isInvalidDecl())
7692 CheckCXXDefaultArguments(Method);
7695 /// CheckConstructorDeclarator - Called by ActOnDeclarator to check
7696 /// the well-formedness of the constructor declarator @p D with type @p
7697 /// R. If there are any errors in the declarator, this routine will
7698 /// emit diagnostics and set the invalid bit to true. In any case, the type
7699 /// will be updated to reflect a well-formed type for the constructor and
7701 QualType Sema::CheckConstructorDeclarator(Declarator &D, QualType R,
7703 bool isVirtual = D.getDeclSpec().isVirtualSpecified();
7705 // C++ [class.ctor]p3:
7706 // A constructor shall not be virtual (10.3) or static (9.4). A
7707 // constructor can be invoked for a const, volatile or const
7708 // volatile object. A constructor shall not be declared const,
7709 // volatile, or const volatile (9.3.2).
7711 if (!D.isInvalidType())
7712 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be)
7713 << "virtual" << SourceRange(D.getDeclSpec().getVirtualSpecLoc())
7714 << SourceRange(D.getIdentifierLoc());
7717 if (SC == SC_Static) {
7718 if (!D.isInvalidType())
7719 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be)
7720 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
7721 << SourceRange(D.getIdentifierLoc());
7726 if (unsigned TypeQuals = D.getDeclSpec().getTypeQualifiers()) {
7727 diagnoseIgnoredQualifiers(
7728 diag::err_constructor_return_type, TypeQuals, SourceLocation(),
7729 D.getDeclSpec().getConstSpecLoc(), D.getDeclSpec().getVolatileSpecLoc(),
7730 D.getDeclSpec().getRestrictSpecLoc(),
7731 D.getDeclSpec().getAtomicSpecLoc());
7735 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
7736 if (FTI.TypeQuals != 0) {
7737 if (FTI.TypeQuals & Qualifiers::Const)
7738 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor)
7739 << "const" << SourceRange(D.getIdentifierLoc());
7740 if (FTI.TypeQuals & Qualifiers::Volatile)
7741 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor)
7742 << "volatile" << SourceRange(D.getIdentifierLoc());
7743 if (FTI.TypeQuals & Qualifiers::Restrict)
7744 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor)
7745 << "restrict" << SourceRange(D.getIdentifierLoc());
7749 // C++0x [class.ctor]p4:
7750 // A constructor shall not be declared with a ref-qualifier.
7751 if (FTI.hasRefQualifier()) {
7752 Diag(FTI.getRefQualifierLoc(), diag::err_ref_qualifier_constructor)
7753 << FTI.RefQualifierIsLValueRef
7754 << FixItHint::CreateRemoval(FTI.getRefQualifierLoc());
7758 // Rebuild the function type "R" without any type qualifiers (in
7759 // case any of the errors above fired) and with "void" as the
7760 // return type, since constructors don't have return types.
7761 const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
7762 if (Proto->getReturnType() == Context.VoidTy && !D.isInvalidType())
7765 FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
7767 EPI.RefQualifier = RQ_None;
7769 return Context.getFunctionType(Context.VoidTy, Proto->getParamTypes(), EPI);
7772 /// CheckConstructor - Checks a fully-formed constructor for
7773 /// well-formedness, issuing any diagnostics required. Returns true if
7774 /// the constructor declarator is invalid.
7775 void Sema::CheckConstructor(CXXConstructorDecl *Constructor) {
7776 CXXRecordDecl *ClassDecl
7777 = dyn_cast<CXXRecordDecl>(Constructor->getDeclContext());
7779 return Constructor->setInvalidDecl();
7781 // C++ [class.copy]p3:
7782 // A declaration of a constructor for a class X is ill-formed if
7783 // its first parameter is of type (optionally cv-qualified) X and
7784 // either there are no other parameters or else all other
7785 // parameters have default arguments.
7786 if (!Constructor->isInvalidDecl() &&
7787 ((Constructor->getNumParams() == 1) ||
7788 (Constructor->getNumParams() > 1 &&
7789 Constructor->getParamDecl(1)->hasDefaultArg())) &&
7790 Constructor->getTemplateSpecializationKind()
7791 != TSK_ImplicitInstantiation) {
7792 QualType ParamType = Constructor->getParamDecl(0)->getType();
7793 QualType ClassTy = Context.getTagDeclType(ClassDecl);
7794 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) {
7795 SourceLocation ParamLoc = Constructor->getParamDecl(0)->getLocation();
7796 const char *ConstRef
7797 = Constructor->getParamDecl(0)->getIdentifier() ? "const &"
7799 Diag(ParamLoc, diag::err_constructor_byvalue_arg)
7800 << FixItHint::CreateInsertion(ParamLoc, ConstRef);
7802 // FIXME: Rather that making the constructor invalid, we should endeavor
7804 Constructor->setInvalidDecl();
7809 /// CheckDestructor - Checks a fully-formed destructor definition for
7810 /// well-formedness, issuing any diagnostics required. Returns true
7812 bool Sema::CheckDestructor(CXXDestructorDecl *Destructor) {
7813 CXXRecordDecl *RD = Destructor->getParent();
7815 if (!Destructor->getOperatorDelete() && Destructor->isVirtual()) {
7818 if (!Destructor->isImplicit())
7819 Loc = Destructor->getLocation();
7821 Loc = RD->getLocation();
7823 // If we have a virtual destructor, look up the deallocation function
7824 if (FunctionDecl *OperatorDelete =
7825 FindDeallocationFunctionForDestructor(Loc, RD)) {
7826 MarkFunctionReferenced(Loc, OperatorDelete);
7827 Destructor->setOperatorDelete(OperatorDelete);
7834 /// CheckDestructorDeclarator - Called by ActOnDeclarator to check
7835 /// the well-formednes of the destructor declarator @p D with type @p
7836 /// R. If there are any errors in the declarator, this routine will
7837 /// emit diagnostics and set the declarator to invalid. Even if this happens,
7838 /// will be updated to reflect a well-formed type for the destructor and
7840 QualType Sema::CheckDestructorDeclarator(Declarator &D, QualType R,
7842 // C++ [class.dtor]p1:
7843 // [...] A typedef-name that names a class is a class-name
7844 // (7.1.3); however, a typedef-name that names a class shall not
7845 // be used as the identifier in the declarator for a destructor
7847 QualType DeclaratorType = GetTypeFromParser(D.getName().DestructorName);
7848 if (const TypedefType *TT = DeclaratorType->getAs<TypedefType>())
7849 Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name)
7850 << DeclaratorType << isa<TypeAliasDecl>(TT->getDecl());
7851 else if (const TemplateSpecializationType *TST =
7852 DeclaratorType->getAs<TemplateSpecializationType>())
7853 if (TST->isTypeAlias())
7854 Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name)
7855 << DeclaratorType << 1;
7857 // C++ [class.dtor]p2:
7858 // A destructor is used to destroy objects of its class type. A
7859 // destructor takes no parameters, and no return type can be
7860 // specified for it (not even void). The address of a destructor
7861 // shall not be taken. A destructor shall not be static. A
7862 // destructor can be invoked for a const, volatile or const
7863 // volatile object. A destructor shall not be declared const,
7864 // volatile or const volatile (9.3.2).
7865 if (SC == SC_Static) {
7866 if (!D.isInvalidType())
7867 Diag(D.getIdentifierLoc(), diag::err_destructor_cannot_be)
7868 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
7869 << SourceRange(D.getIdentifierLoc())
7870 << FixItHint::CreateRemoval(D.getDeclSpec().getStorageClassSpecLoc());
7874 if (!D.isInvalidType()) {
7875 // Destructors don't have return types, but the parser will
7876 // happily parse something like:
7882 // The return type will be eliminated later.
7883 if (D.getDeclSpec().hasTypeSpecifier())
7884 Diag(D.getIdentifierLoc(), diag::err_destructor_return_type)
7885 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
7886 << SourceRange(D.getIdentifierLoc());
7887 else if (unsigned TypeQuals = D.getDeclSpec().getTypeQualifiers()) {
7888 diagnoseIgnoredQualifiers(diag::err_destructor_return_type, TypeQuals,
7890 D.getDeclSpec().getConstSpecLoc(),
7891 D.getDeclSpec().getVolatileSpecLoc(),
7892 D.getDeclSpec().getRestrictSpecLoc(),
7893 D.getDeclSpec().getAtomicSpecLoc());
7898 DeclaratorChunk::FunctionTypeInfo &FTI = D.getFunctionTypeInfo();
7899 if (FTI.TypeQuals != 0 && !D.isInvalidType()) {
7900 if (FTI.TypeQuals & Qualifiers::Const)
7901 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor)
7902 << "const" << SourceRange(D.getIdentifierLoc());
7903 if (FTI.TypeQuals & Qualifiers::Volatile)
7904 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor)
7905 << "volatile" << SourceRange(D.getIdentifierLoc());
7906 if (FTI.TypeQuals & Qualifiers::Restrict)
7907 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor)
7908 << "restrict" << SourceRange(D.getIdentifierLoc());
7912 // C++0x [class.dtor]p2:
7913 // A destructor shall not be declared with a ref-qualifier.
7914 if (FTI.hasRefQualifier()) {
7915 Diag(FTI.getRefQualifierLoc(), diag::err_ref_qualifier_destructor)
7916 << FTI.RefQualifierIsLValueRef
7917 << FixItHint::CreateRemoval(FTI.getRefQualifierLoc());
7921 // Make sure we don't have any parameters.
7922 if (FTIHasNonVoidParameters(FTI)) {
7923 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params);
7925 // Delete the parameters.
7930 // Make sure the destructor isn't variadic.
7931 if (FTI.isVariadic) {
7932 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic);
7936 // Rebuild the function type "R" without any type qualifiers or
7937 // parameters (in case any of the errors above fired) and with
7938 // "void" as the return type, since destructors don't have return
7940 if (!D.isInvalidType())
7943 const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
7944 FunctionProtoType::ExtProtoInfo EPI = Proto->getExtProtoInfo();
7945 EPI.Variadic = false;
7947 EPI.RefQualifier = RQ_None;
7948 return Context.getFunctionType(Context.VoidTy, None, EPI);
7951 static void extendLeft(SourceRange &R, SourceRange Before) {
7952 if (Before.isInvalid())
7954 R.setBegin(Before.getBegin());
7955 if (R.getEnd().isInvalid())
7956 R.setEnd(Before.getEnd());
7959 static void extendRight(SourceRange &R, SourceRange After) {
7960 if (After.isInvalid())
7962 if (R.getBegin().isInvalid())
7963 R.setBegin(After.getBegin());
7964 R.setEnd(After.getEnd());
7967 /// CheckConversionDeclarator - Called by ActOnDeclarator to check the
7968 /// well-formednes of the conversion function declarator @p D with
7969 /// type @p R. If there are any errors in the declarator, this routine
7970 /// will emit diagnostics and return true. Otherwise, it will return
7971 /// false. Either way, the type @p R will be updated to reflect a
7972 /// well-formed type for the conversion operator.
7973 void Sema::CheckConversionDeclarator(Declarator &D, QualType &R,
7975 // C++ [class.conv.fct]p1:
7976 // Neither parameter types nor return type can be specified. The
7977 // type of a conversion function (8.3.5) is "function taking no
7978 // parameter returning conversion-type-id."
7979 if (SC == SC_Static) {
7980 if (!D.isInvalidType())
7981 Diag(D.getIdentifierLoc(), diag::err_conv_function_not_member)
7982 << SourceRange(D.getDeclSpec().getStorageClassSpecLoc())
7983 << D.getName().getSourceRange();
7988 TypeSourceInfo *ConvTSI = nullptr;
7990 GetTypeFromParser(D.getName().ConversionFunctionId, &ConvTSI);
7992 if (D.getDeclSpec().hasTypeSpecifier() && !D.isInvalidType()) {
7993 // Conversion functions don't have return types, but the parser will
7994 // happily parse something like:
7997 // float operator bool();
8000 // The return type will be changed later anyway.
8001 Diag(D.getIdentifierLoc(), diag::err_conv_function_return_type)
8002 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc())
8003 << SourceRange(D.getIdentifierLoc());
8007 const FunctionProtoType *Proto = R->getAs<FunctionProtoType>();
8009 // Make sure we don't have any parameters.
8010 if (Proto->getNumParams() > 0) {
8011 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params);
8013 // Delete the parameters.
8014 D.getFunctionTypeInfo().freeParams();
8016 } else if (Proto->isVariadic()) {
8017 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic);
8021 // Diagnose "&operator bool()" and other such nonsense. This
8022 // is actually a gcc extension which we don't support.
8023 if (Proto->getReturnType() != ConvType) {
8024 bool NeedsTypedef = false;
8025 SourceRange Before, After;
8027 // Walk the chunks and extract information on them for our diagnostic.
8028 bool PastFunctionChunk = false;
8029 for (auto &Chunk : D.type_objects()) {
8030 switch (Chunk.Kind) {
8031 case DeclaratorChunk::Function:
8032 if (!PastFunctionChunk) {
8033 if (Chunk.Fun.HasTrailingReturnType) {
8034 TypeSourceInfo *TRT = nullptr;
8035 GetTypeFromParser(Chunk.Fun.getTrailingReturnType(), &TRT);
8036 if (TRT) extendRight(After, TRT->getTypeLoc().getSourceRange());
8038 PastFunctionChunk = true;
8042 case DeclaratorChunk::Array:
8043 NeedsTypedef = true;
8044 extendRight(After, Chunk.getSourceRange());
8047 case DeclaratorChunk::Pointer:
8048 case DeclaratorChunk::BlockPointer:
8049 case DeclaratorChunk::Reference:
8050 case DeclaratorChunk::MemberPointer:
8051 case DeclaratorChunk::Pipe:
8052 extendLeft(Before, Chunk.getSourceRange());
8055 case DeclaratorChunk::Paren:
8056 extendLeft(Before, Chunk.Loc);
8057 extendRight(After, Chunk.EndLoc);
8062 SourceLocation Loc = Before.isValid() ? Before.getBegin() :
8063 After.isValid() ? After.getBegin() :
8064 D.getIdentifierLoc();
8065 auto &&DB = Diag(Loc, diag::err_conv_function_with_complex_decl);
8066 DB << Before << After;
8068 if (!NeedsTypedef) {
8069 DB << /*don't need a typedef*/0;
8071 // If we can provide a correct fix-it hint, do so.
8072 if (After.isInvalid() && ConvTSI) {
8073 SourceLocation InsertLoc =
8074 getLocForEndOfToken(ConvTSI->getTypeLoc().getLocEnd());
8075 DB << FixItHint::CreateInsertion(InsertLoc, " ")
8076 << FixItHint::CreateInsertionFromRange(
8077 InsertLoc, CharSourceRange::getTokenRange(Before))
8078 << FixItHint::CreateRemoval(Before);
8080 } else if (!Proto->getReturnType()->isDependentType()) {
8081 DB << /*typedef*/1 << Proto->getReturnType();
8082 } else if (getLangOpts().CPlusPlus11) {
8083 DB << /*alias template*/2 << Proto->getReturnType();
8085 DB << /*might not be fixable*/3;
8088 // Recover by incorporating the other type chunks into the result type.
8089 // Note, this does *not* change the name of the function. This is compatible
8090 // with the GCC extension:
8091 // struct S { &operator int(); } s;
8092 // int &r = s.operator int(); // ok in GCC
8093 // S::operator int&() {} // error in GCC, function name is 'operator int'.
8094 ConvType = Proto->getReturnType();
8097 // C++ [class.conv.fct]p4:
8098 // The conversion-type-id shall not represent a function type nor
8100 if (ConvType->isArrayType()) {
8101 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array);
8102 ConvType = Context.getPointerType(ConvType);
8104 } else if (ConvType->isFunctionType()) {
8105 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function);
8106 ConvType = Context.getPointerType(ConvType);
8110 // Rebuild the function type "R" without any parameters (in case any
8111 // of the errors above fired) and with the conversion type as the
8113 if (D.isInvalidType())
8114 R = Context.getFunctionType(ConvType, None, Proto->getExtProtoInfo());
8116 // C++0x explicit conversion operators.
8117 if (D.getDeclSpec().isExplicitSpecified())
8118 Diag(D.getDeclSpec().getExplicitSpecLoc(),
8119 getLangOpts().CPlusPlus11 ?
8120 diag::warn_cxx98_compat_explicit_conversion_functions :
8121 diag::ext_explicit_conversion_functions)
8122 << SourceRange(D.getDeclSpec().getExplicitSpecLoc());
8125 /// ActOnConversionDeclarator - Called by ActOnDeclarator to complete
8126 /// the declaration of the given C++ conversion function. This routine
8127 /// is responsible for recording the conversion function in the C++
8128 /// class, if possible.
8129 Decl *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) {
8130 assert(Conversion && "Expected to receive a conversion function declaration");
8132 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Conversion->getDeclContext());
8134 // Make sure we aren't redeclaring the conversion function.
8135 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType());
8137 // C++ [class.conv.fct]p1:
8138 // [...] A conversion function is never used to convert a
8139 // (possibly cv-qualified) object to the (possibly cv-qualified)
8140 // same object type (or a reference to it), to a (possibly
8141 // cv-qualified) base class of that type (or a reference to it),
8142 // or to (possibly cv-qualified) void.
8143 // FIXME: Suppress this warning if the conversion function ends up being a
8144 // virtual function that overrides a virtual function in a base class.
8146 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
8147 if (const ReferenceType *ConvTypeRef = ConvType->getAs<ReferenceType>())
8148 ConvType = ConvTypeRef->getPointeeType();
8149 if (Conversion->getTemplateSpecializationKind() != TSK_Undeclared &&
8150 Conversion->getTemplateSpecializationKind() != TSK_ExplicitSpecialization)
8151 /* Suppress diagnostics for instantiations. */;
8152 else if (ConvType->isRecordType()) {
8153 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType();
8154 if (ConvType == ClassType)
8155 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used)
8157 else if (IsDerivedFrom(Conversion->getLocation(), ClassType, ConvType))
8158 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used)
8159 << ClassType << ConvType;
8160 } else if (ConvType->isVoidType()) {
8161 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used)
8162 << ClassType << ConvType;
8165 if (FunctionTemplateDecl *ConversionTemplate
8166 = Conversion->getDescribedFunctionTemplate())
8167 return ConversionTemplate;
8173 /// Utility class to accumulate and print a diagnostic listing the invalid
8174 /// specifier(s) on a declaration.
8175 struct BadSpecifierDiagnoser {
8176 BadSpecifierDiagnoser(Sema &S, SourceLocation Loc, unsigned DiagID)
8177 : S(S), Diagnostic(S.Diag(Loc, DiagID)) {}
8178 ~BadSpecifierDiagnoser() {
8179 Diagnostic << Specifiers;
8182 template<typename T> void check(SourceLocation SpecLoc, T Spec) {
8183 return check(SpecLoc, DeclSpec::getSpecifierName(Spec));
8185 void check(SourceLocation SpecLoc, DeclSpec::TST Spec) {
8186 return check(SpecLoc,
8187 DeclSpec::getSpecifierName(Spec, S.getPrintingPolicy()));
8189 void check(SourceLocation SpecLoc, const char *Spec) {
8190 if (SpecLoc.isInvalid()) return;
8191 Diagnostic << SourceRange(SpecLoc, SpecLoc);
8192 if (!Specifiers.empty()) Specifiers += " ";
8197 Sema::SemaDiagnosticBuilder Diagnostic;
8198 std::string Specifiers;
8202 /// Check the validity of a declarator that we parsed for a deduction-guide.
8203 /// These aren't actually declarators in the grammar, so we need to check that
8204 /// the user didn't specify any pieces that are not part of the deduction-guide
8206 void Sema::CheckDeductionGuideDeclarator(Declarator &D, QualType &R,
8208 TemplateName GuidedTemplate = D.getName().TemplateName.get().get();
8209 TemplateDecl *GuidedTemplateDecl = GuidedTemplate.getAsTemplateDecl();
8210 assert(GuidedTemplateDecl && "missing template decl for deduction guide");
8212 // C++ [temp.deduct.guide]p3:
8213 // A deduction-gide shall be declared in the same scope as the
8214 // corresponding class template.
8215 if (!CurContext->getRedeclContext()->Equals(
8216 GuidedTemplateDecl->getDeclContext()->getRedeclContext())) {
8217 Diag(D.getIdentifierLoc(), diag::err_deduction_guide_wrong_scope)
8218 << GuidedTemplateDecl;
8219 Diag(GuidedTemplateDecl->getLocation(), diag::note_template_decl_here);
8222 auto &DS = D.getMutableDeclSpec();
8223 // We leave 'friend' and 'virtual' to be rejected in the normal way.
8224 if (DS.hasTypeSpecifier() || DS.getTypeQualifiers() ||
8225 DS.getStorageClassSpecLoc().isValid() || DS.isInlineSpecified() ||
8226 DS.isNoreturnSpecified() || DS.isConstexprSpecified() ||
8227 DS.isConceptSpecified()) {
8228 BadSpecifierDiagnoser Diagnoser(
8229 *this, D.getIdentifierLoc(),
8230 diag::err_deduction_guide_invalid_specifier);
8232 Diagnoser.check(DS.getStorageClassSpecLoc(), DS.getStorageClassSpec());
8233 DS.ClearStorageClassSpecs();
8236 // 'explicit' is permitted.
8237 Diagnoser.check(DS.getInlineSpecLoc(), "inline");
8238 Diagnoser.check(DS.getNoreturnSpecLoc(), "_Noreturn");
8239 Diagnoser.check(DS.getConstexprSpecLoc(), "constexpr");
8240 Diagnoser.check(DS.getConceptSpecLoc(), "concept");
8241 DS.ClearConstexprSpec();
8242 DS.ClearConceptSpec();
8244 Diagnoser.check(DS.getConstSpecLoc(), "const");
8245 Diagnoser.check(DS.getRestrictSpecLoc(), "__restrict");
8246 Diagnoser.check(DS.getVolatileSpecLoc(), "volatile");
8247 Diagnoser.check(DS.getAtomicSpecLoc(), "_Atomic");
8248 Diagnoser.check(DS.getUnalignedSpecLoc(), "__unaligned");
8249 DS.ClearTypeQualifiers();
8251 Diagnoser.check(DS.getTypeSpecComplexLoc(), DS.getTypeSpecComplex());
8252 Diagnoser.check(DS.getTypeSpecSignLoc(), DS.getTypeSpecSign());
8253 Diagnoser.check(DS.getTypeSpecWidthLoc(), DS.getTypeSpecWidth());
8254 Diagnoser.check(DS.getTypeSpecTypeLoc(), DS.getTypeSpecType());
8255 DS.ClearTypeSpecType();
8258 if (D.isInvalidType())
8261 // Check the declarator is simple enough.
8262 bool FoundFunction = false;
8263 for (const DeclaratorChunk &Chunk : llvm::reverse(D.type_objects())) {
8264 if (Chunk.Kind == DeclaratorChunk::Paren)
8266 if (Chunk.Kind != DeclaratorChunk::Function || FoundFunction) {
8267 Diag(D.getDeclSpec().getLocStart(),
8268 diag::err_deduction_guide_with_complex_decl)
8269 << D.getSourceRange();
8272 if (!Chunk.Fun.hasTrailingReturnType()) {
8273 Diag(D.getName().getLocStart(),
8274 diag::err_deduction_guide_no_trailing_return_type);
8278 // Check that the return type is written as a specialization of
8279 // the template specified as the deduction-guide's name.
8280 ParsedType TrailingReturnType = Chunk.Fun.getTrailingReturnType();
8281 TypeSourceInfo *TSI = nullptr;
8282 QualType RetTy = GetTypeFromParser(TrailingReturnType, &TSI);
8283 assert(TSI && "deduction guide has valid type but invalid return type?");
8284 bool AcceptableReturnType = false;
8285 bool MightInstantiateToSpecialization = false;
8287 TSI->getTypeLoc().getAs<TemplateSpecializationTypeLoc>()) {
8288 TemplateName SpecifiedName = RetTST.getTypePtr()->getTemplateName();
8289 bool TemplateMatches =
8290 Context.hasSameTemplateName(SpecifiedName, GuidedTemplate);
8291 if (SpecifiedName.getKind() == TemplateName::Template && TemplateMatches)
8292 AcceptableReturnType = true;
8294 // This could still instantiate to the right type, unless we know it
8295 // names the wrong class template.
8296 auto *TD = SpecifiedName.getAsTemplateDecl();
8297 MightInstantiateToSpecialization = !(TD && isa<ClassTemplateDecl>(TD) &&
8300 } else if (!RetTy.hasQualifiers() && RetTy->isDependentType()) {
8301 MightInstantiateToSpecialization = true;
8304 if (!AcceptableReturnType) {
8305 Diag(TSI->getTypeLoc().getLocStart(),
8306 diag::err_deduction_guide_bad_trailing_return_type)
8307 << GuidedTemplate << TSI->getType() << MightInstantiateToSpecialization
8308 << TSI->getTypeLoc().getSourceRange();
8311 // Keep going to check that we don't have any inner declarator pieces (we
8312 // could still have a function returning a pointer to a function).
8313 FoundFunction = true;
8316 if (D.isFunctionDefinition())
8317 Diag(D.getIdentifierLoc(), diag::err_deduction_guide_defines_function);
8320 //===----------------------------------------------------------------------===//
8321 // Namespace Handling
8322 //===----------------------------------------------------------------------===//
8324 /// \brief Diagnose a mismatch in 'inline' qualifiers when a namespace is
8326 static void DiagnoseNamespaceInlineMismatch(Sema &S, SourceLocation KeywordLoc,
8328 IdentifierInfo *II, bool *IsInline,
8329 NamespaceDecl *PrevNS) {
8330 assert(*IsInline != PrevNS->isInline());
8332 // HACK: Work around a bug in libstdc++4.6's <atomic>, where
8333 // std::__atomic[0,1,2] are defined as non-inline namespaces, then reopened as
8334 // inline namespaces, with the intention of bringing names into namespace std.
8336 // We support this just well enough to get that case working; this is not
8337 // sufficient to support reopening namespaces as inline in general.
8338 if (*IsInline && II && II->getName().startswith("__atomic") &&
8339 S.getSourceManager().isInSystemHeader(Loc)) {
8340 // Mark all prior declarations of the namespace as inline.
8341 for (NamespaceDecl *NS = PrevNS->getMostRecentDecl(); NS;
8342 NS = NS->getPreviousDecl())
8343 NS->setInline(*IsInline);
8344 // Patch up the lookup table for the containing namespace. This isn't really
8345 // correct, but it's good enough for this particular case.
8346 for (auto *I : PrevNS->decls())
8347 if (auto *ND = dyn_cast<NamedDecl>(I))
8348 PrevNS->getParent()->makeDeclVisibleInContext(ND);
8352 if (PrevNS->isInline())
8353 // The user probably just forgot the 'inline', so suggest that it
8355 S.Diag(Loc, diag::warn_inline_namespace_reopened_noninline)
8356 << FixItHint::CreateInsertion(KeywordLoc, "inline ");
8358 S.Diag(Loc, diag::err_inline_namespace_mismatch);
8360 S.Diag(PrevNS->getLocation(), diag::note_previous_definition);
8361 *IsInline = PrevNS->isInline();
8364 /// ActOnStartNamespaceDef - This is called at the start of a namespace
8366 Decl *Sema::ActOnStartNamespaceDef(Scope *NamespcScope,
8367 SourceLocation InlineLoc,
8368 SourceLocation NamespaceLoc,
8369 SourceLocation IdentLoc,
8371 SourceLocation LBrace,
8372 AttributeList *AttrList,
8373 UsingDirectiveDecl *&UD) {
8374 SourceLocation StartLoc = InlineLoc.isValid() ? InlineLoc : NamespaceLoc;
8375 // For anonymous namespace, take the location of the left brace.
8376 SourceLocation Loc = II ? IdentLoc : LBrace;
8377 bool IsInline = InlineLoc.isValid();
8378 bool IsInvalid = false;
8380 bool AddToKnown = false;
8381 Scope *DeclRegionScope = NamespcScope->getParent();
8383 NamespaceDecl *PrevNS = nullptr;
8385 // C++ [namespace.def]p2:
8386 // The identifier in an original-namespace-definition shall not
8387 // have been previously defined in the declarative region in
8388 // which the original-namespace-definition appears. The
8389 // identifier in an original-namespace-definition is the name of
8390 // the namespace. Subsequently in that declarative region, it is
8391 // treated as an original-namespace-name.
8393 // Since namespace names are unique in their scope, and we don't
8394 // look through using directives, just look for any ordinary names
8395 // as if by qualified name lookup.
8396 LookupResult R(*this, II, IdentLoc, LookupOrdinaryName, ForRedeclaration);
8397 LookupQualifiedName(R, CurContext->getRedeclContext());
8398 NamedDecl *PrevDecl =
8399 R.isSingleResult() ? R.getRepresentativeDecl() : nullptr;
8400 PrevNS = dyn_cast_or_null<NamespaceDecl>(PrevDecl);
8403 // This is an extended namespace definition.
8404 if (IsInline != PrevNS->isInline())
8405 DiagnoseNamespaceInlineMismatch(*this, NamespaceLoc, Loc, II,
8407 } else if (PrevDecl) {
8408 // This is an invalid name redefinition.
8409 Diag(Loc, diag::err_redefinition_different_kind)
8411 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
8413 // Continue on to push Namespc as current DeclContext and return it.
8414 } else if (II->isStr("std") &&
8415 CurContext->getRedeclContext()->isTranslationUnit()) {
8416 // This is the first "real" definition of the namespace "std", so update
8417 // our cache of the "std" namespace to point at this definition.
8418 PrevNS = getStdNamespace();
8420 AddToKnown = !IsInline;
8422 // We've seen this namespace for the first time.
8423 AddToKnown = !IsInline;
8426 // Anonymous namespaces.
8428 // Determine whether the parent already has an anonymous namespace.
8429 DeclContext *Parent = CurContext->getRedeclContext();
8430 if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(Parent)) {
8431 PrevNS = TU->getAnonymousNamespace();
8433 NamespaceDecl *ND = cast<NamespaceDecl>(Parent);
8434 PrevNS = ND->getAnonymousNamespace();
8437 if (PrevNS && IsInline != PrevNS->isInline())
8438 DiagnoseNamespaceInlineMismatch(*this, NamespaceLoc, NamespaceLoc, II,
8442 NamespaceDecl *Namespc = NamespaceDecl::Create(Context, CurContext, IsInline,
8443 StartLoc, Loc, II, PrevNS);
8445 Namespc->setInvalidDecl();
8447 ProcessDeclAttributeList(DeclRegionScope, Namespc, AttrList);
8448 AddPragmaAttributes(DeclRegionScope, Namespc);
8450 // FIXME: Should we be merging attributes?
8451 if (const VisibilityAttr *Attr = Namespc->getAttr<VisibilityAttr>())
8452 PushNamespaceVisibilityAttr(Attr, Loc);
8455 StdNamespace = Namespc;
8457 KnownNamespaces[Namespc] = false;
8460 PushOnScopeChains(Namespc, DeclRegionScope);
8462 // Link the anonymous namespace into its parent.
8463 DeclContext *Parent = CurContext->getRedeclContext();
8464 if (TranslationUnitDecl *TU = dyn_cast<TranslationUnitDecl>(Parent)) {
8465 TU->setAnonymousNamespace(Namespc);
8467 cast<NamespaceDecl>(Parent)->setAnonymousNamespace(Namespc);
8470 CurContext->addDecl(Namespc);
8472 // C++ [namespace.unnamed]p1. An unnamed-namespace-definition
8473 // behaves as if it were replaced by
8474 // namespace unique { /* empty body */ }
8475 // using namespace unique;
8476 // namespace unique { namespace-body }
8477 // where all occurrences of 'unique' in a translation unit are
8478 // replaced by the same identifier and this identifier differs
8479 // from all other identifiers in the entire program.
8481 // We just create the namespace with an empty name and then add an
8482 // implicit using declaration, just like the standard suggests.
8484 // CodeGen enforces the "universally unique" aspect by giving all
8485 // declarations semantically contained within an anonymous
8486 // namespace internal linkage.
8489 UD = UsingDirectiveDecl::Create(Context, Parent,
8490 /* 'using' */ LBrace,
8491 /* 'namespace' */ SourceLocation(),
8492 /* qualifier */ NestedNameSpecifierLoc(),
8493 /* identifier */ SourceLocation(),
8495 /* Ancestor */ Parent);
8497 Parent->addDecl(UD);
8501 ActOnDocumentableDecl(Namespc);
8503 // Although we could have an invalid decl (i.e. the namespace name is a
8504 // redefinition), push it as current DeclContext and try to continue parsing.
8505 // FIXME: We should be able to push Namespc here, so that the each DeclContext
8506 // for the namespace has the declarations that showed up in that particular
8507 // namespace definition.
8508 PushDeclContext(NamespcScope, Namespc);
8512 /// getNamespaceDecl - Returns the namespace a decl represents. If the decl
8513 /// is a namespace alias, returns the namespace it points to.
8514 static inline NamespaceDecl *getNamespaceDecl(NamedDecl *D) {
8515 if (NamespaceAliasDecl *AD = dyn_cast_or_null<NamespaceAliasDecl>(D))
8516 return AD->getNamespace();
8517 return dyn_cast_or_null<NamespaceDecl>(D);
8520 /// ActOnFinishNamespaceDef - This callback is called after a namespace is
8521 /// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef.
8522 void Sema::ActOnFinishNamespaceDef(Decl *Dcl, SourceLocation RBrace) {
8523 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl);
8524 assert(Namespc && "Invalid parameter, expected NamespaceDecl");
8525 Namespc->setRBraceLoc(RBrace);
8527 if (Namespc->hasAttr<VisibilityAttr>())
8528 PopPragmaVisibility(true, RBrace);
8531 CXXRecordDecl *Sema::getStdBadAlloc() const {
8532 return cast_or_null<CXXRecordDecl>(
8533 StdBadAlloc.get(Context.getExternalSource()));
8536 EnumDecl *Sema::getStdAlignValT() const {
8537 return cast_or_null<EnumDecl>(StdAlignValT.get(Context.getExternalSource()));
8540 NamespaceDecl *Sema::getStdNamespace() const {
8541 return cast_or_null<NamespaceDecl>(
8542 StdNamespace.get(Context.getExternalSource()));
8545 NamespaceDecl *Sema::lookupStdExperimentalNamespace() {
8546 if (!StdExperimentalNamespaceCache) {
8547 if (auto Std = getStdNamespace()) {
8548 LookupResult Result(*this, &PP.getIdentifierTable().get("experimental"),
8549 SourceLocation(), LookupNamespaceName);
8550 if (!LookupQualifiedName(Result, Std) ||
8551 !(StdExperimentalNamespaceCache =
8552 Result.getAsSingle<NamespaceDecl>()))
8553 Result.suppressDiagnostics();
8556 return StdExperimentalNamespaceCache;
8559 /// \brief Retrieve the special "std" namespace, which may require us to
8560 /// implicitly define the namespace.
8561 NamespaceDecl *Sema::getOrCreateStdNamespace() {
8562 if (!StdNamespace) {
8563 // The "std" namespace has not yet been defined, so build one implicitly.
8564 StdNamespace = NamespaceDecl::Create(Context,
8565 Context.getTranslationUnitDecl(),
8567 SourceLocation(), SourceLocation(),
8568 &PP.getIdentifierTable().get("std"),
8569 /*PrevDecl=*/nullptr);
8570 getStdNamespace()->setImplicit(true);
8573 return getStdNamespace();
8576 bool Sema::isStdInitializerList(QualType Ty, QualType *Element) {
8577 assert(getLangOpts().CPlusPlus &&
8578 "Looking for std::initializer_list outside of C++.");
8580 // We're looking for implicit instantiations of
8581 // template <typename E> class std::initializer_list.
8583 if (!StdNamespace) // If we haven't seen namespace std yet, this can't be it.
8586 ClassTemplateDecl *Template = nullptr;
8587 const TemplateArgument *Arguments = nullptr;
8589 if (const RecordType *RT = Ty->getAs<RecordType>()) {
8591 ClassTemplateSpecializationDecl *Specialization =
8592 dyn_cast<ClassTemplateSpecializationDecl>(RT->getDecl());
8593 if (!Specialization)
8596 Template = Specialization->getSpecializedTemplate();
8597 Arguments = Specialization->getTemplateArgs().data();
8598 } else if (const TemplateSpecializationType *TST =
8599 Ty->getAs<TemplateSpecializationType>()) {
8600 Template = dyn_cast_or_null<ClassTemplateDecl>(
8601 TST->getTemplateName().getAsTemplateDecl());
8602 Arguments = TST->getArgs();
8607 if (!StdInitializerList) {
8608 // Haven't recognized std::initializer_list yet, maybe this is it.
8609 CXXRecordDecl *TemplateClass = Template->getTemplatedDecl();
8610 if (TemplateClass->getIdentifier() !=
8611 &PP.getIdentifierTable().get("initializer_list") ||
8612 !getStdNamespace()->InEnclosingNamespaceSetOf(
8613 TemplateClass->getDeclContext()))
8615 // This is a template called std::initializer_list, but is it the right
8617 TemplateParameterList *Params = Template->getTemplateParameters();
8618 if (Params->getMinRequiredArguments() != 1)
8620 if (!isa<TemplateTypeParmDecl>(Params->getParam(0)))
8623 // It's the right template.
8624 StdInitializerList = Template;
8627 if (Template->getCanonicalDecl() != StdInitializerList->getCanonicalDecl())
8630 // This is an instance of std::initializer_list. Find the argument type.
8632 *Element = Arguments[0].getAsType();
8636 static ClassTemplateDecl *LookupStdInitializerList(Sema &S, SourceLocation Loc){
8637 NamespaceDecl *Std = S.getStdNamespace();
8639 S.Diag(Loc, diag::err_implied_std_initializer_list_not_found);
8643 LookupResult Result(S, &S.PP.getIdentifierTable().get("initializer_list"),
8644 Loc, Sema::LookupOrdinaryName);
8645 if (!S.LookupQualifiedName(Result, Std)) {
8646 S.Diag(Loc, diag::err_implied_std_initializer_list_not_found);
8649 ClassTemplateDecl *Template = Result.getAsSingle<ClassTemplateDecl>();
8651 Result.suppressDiagnostics();
8652 // We found something weird. Complain about the first thing we found.
8653 NamedDecl *Found = *Result.begin();
8654 S.Diag(Found->getLocation(), diag::err_malformed_std_initializer_list);
8658 // We found some template called std::initializer_list. Now verify that it's
8660 TemplateParameterList *Params = Template->getTemplateParameters();
8661 if (Params->getMinRequiredArguments() != 1 ||
8662 !isa<TemplateTypeParmDecl>(Params->getParam(0))) {
8663 S.Diag(Template->getLocation(), diag::err_malformed_std_initializer_list);
8670 QualType Sema::BuildStdInitializerList(QualType Element, SourceLocation Loc) {
8671 if (!StdInitializerList) {
8672 StdInitializerList = LookupStdInitializerList(*this, Loc);
8673 if (!StdInitializerList)
8677 TemplateArgumentListInfo Args(Loc, Loc);
8678 Args.addArgument(TemplateArgumentLoc(TemplateArgument(Element),
8679 Context.getTrivialTypeSourceInfo(Element,
8681 return Context.getCanonicalType(
8682 CheckTemplateIdType(TemplateName(StdInitializerList), Loc, Args));
8685 bool Sema::isInitListConstructor(const FunctionDecl *Ctor) {
8686 // C++ [dcl.init.list]p2:
8687 // A constructor is an initializer-list constructor if its first parameter
8688 // is of type std::initializer_list<E> or reference to possibly cv-qualified
8689 // std::initializer_list<E> for some type E, and either there are no other
8690 // parameters or else all other parameters have default arguments.
8691 if (Ctor->getNumParams() < 1 ||
8692 (Ctor->getNumParams() > 1 && !Ctor->getParamDecl(1)->hasDefaultArg()))
8695 QualType ArgType = Ctor->getParamDecl(0)->getType();
8696 if (const ReferenceType *RT = ArgType->getAs<ReferenceType>())
8697 ArgType = RT->getPointeeType().getUnqualifiedType();
8699 return isStdInitializerList(ArgType, nullptr);
8702 /// \brief Determine whether a using statement is in a context where it will be
8703 /// apply in all contexts.
8704 static bool IsUsingDirectiveInToplevelContext(DeclContext *CurContext) {
8705 switch (CurContext->getDeclKind()) {
8706 case Decl::TranslationUnit:
8708 case Decl::LinkageSpec:
8709 return IsUsingDirectiveInToplevelContext(CurContext->getParent());
8717 // Callback to only accept typo corrections that are namespaces.
8718 class NamespaceValidatorCCC : public CorrectionCandidateCallback {
8720 bool ValidateCandidate(const TypoCorrection &candidate) override {
8721 if (NamedDecl *ND = candidate.getCorrectionDecl())
8722 return isa<NamespaceDecl>(ND) || isa<NamespaceAliasDecl>(ND);
8729 static bool TryNamespaceTypoCorrection(Sema &S, LookupResult &R, Scope *Sc,
8731 SourceLocation IdentLoc,
8732 IdentifierInfo *Ident) {
8734 if (TypoCorrection Corrected =
8735 S.CorrectTypo(R.getLookupNameInfo(), R.getLookupKind(), Sc, &SS,
8736 llvm::make_unique<NamespaceValidatorCCC>(),
8737 Sema::CTK_ErrorRecovery)) {
8738 if (DeclContext *DC = S.computeDeclContext(SS, false)) {
8739 std::string CorrectedStr(Corrected.getAsString(S.getLangOpts()));
8740 bool DroppedSpecifier = Corrected.WillReplaceSpecifier() &&
8741 Ident->getName().equals(CorrectedStr);
8742 S.diagnoseTypo(Corrected,
8743 S.PDiag(diag::err_using_directive_member_suggest)
8744 << Ident << DC << DroppedSpecifier << SS.getRange(),
8745 S.PDiag(diag::note_namespace_defined_here));
8747 S.diagnoseTypo(Corrected,
8748 S.PDiag(diag::err_using_directive_suggest) << Ident,
8749 S.PDiag(diag::note_namespace_defined_here));
8751 R.addDecl(Corrected.getFoundDecl());
8757 Decl *Sema::ActOnUsingDirective(Scope *S,
8758 SourceLocation UsingLoc,
8759 SourceLocation NamespcLoc,
8761 SourceLocation IdentLoc,
8762 IdentifierInfo *NamespcName,
8763 AttributeList *AttrList) {
8764 assert(!SS.isInvalid() && "Invalid CXXScopeSpec.");
8765 assert(NamespcName && "Invalid NamespcName.");
8766 assert(IdentLoc.isValid() && "Invalid NamespceName location.");
8768 // This can only happen along a recovery path.
8769 while (S->isTemplateParamScope())
8771 assert(S->getFlags() & Scope::DeclScope && "Invalid Scope.");
8773 UsingDirectiveDecl *UDir = nullptr;
8774 NestedNameSpecifier *Qualifier = nullptr;
8776 Qualifier = SS.getScopeRep();
8778 // Lookup namespace name.
8779 LookupResult R(*this, NamespcName, IdentLoc, LookupNamespaceName);
8780 LookupParsedName(R, S, &SS);
8781 if (R.isAmbiguous())
8786 // Allow "using namespace std;" or "using namespace ::std;" even if
8787 // "std" hasn't been defined yet, for GCC compatibility.
8788 if ((!Qualifier || Qualifier->getKind() == NestedNameSpecifier::Global) &&
8789 NamespcName->isStr("std")) {
8790 Diag(IdentLoc, diag::ext_using_undefined_std);
8791 R.addDecl(getOrCreateStdNamespace());
8794 // Otherwise, attempt typo correction.
8795 else TryNamespaceTypoCorrection(*this, R, S, SS, IdentLoc, NamespcName);
8799 NamedDecl *Named = R.getRepresentativeDecl();
8800 NamespaceDecl *NS = R.getAsSingle<NamespaceDecl>();
8801 assert(NS && "expected namespace decl");
8803 // The use of a nested name specifier may trigger deprecation warnings.
8804 DiagnoseUseOfDecl(Named, IdentLoc);
8806 // C++ [namespace.udir]p1:
8807 // A using-directive specifies that the names in the nominated
8808 // namespace can be used in the scope in which the
8809 // using-directive appears after the using-directive. During
8810 // unqualified name lookup (3.4.1), the names appear as if they
8811 // were declared in the nearest enclosing namespace which
8812 // contains both the using-directive and the nominated
8813 // namespace. [Note: in this context, "contains" means "contains
8814 // directly or indirectly". ]
8816 // Find enclosing context containing both using-directive and
8817 // nominated namespace.
8818 DeclContext *CommonAncestor = cast<DeclContext>(NS);
8819 while (CommonAncestor && !CommonAncestor->Encloses(CurContext))
8820 CommonAncestor = CommonAncestor->getParent();
8822 UDir = UsingDirectiveDecl::Create(Context, CurContext, UsingLoc, NamespcLoc,
8823 SS.getWithLocInContext(Context),
8824 IdentLoc, Named, CommonAncestor);
8826 if (IsUsingDirectiveInToplevelContext(CurContext) &&
8827 !SourceMgr.isInMainFile(SourceMgr.getExpansionLoc(IdentLoc))) {
8828 Diag(IdentLoc, diag::warn_using_directive_in_header);
8831 PushUsingDirective(S, UDir);
8833 Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange();
8837 ProcessDeclAttributeList(S, UDir, AttrList);
8842 void Sema::PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir) {
8843 // If the scope has an associated entity and the using directive is at
8844 // namespace or translation unit scope, add the UsingDirectiveDecl into
8845 // its lookup structure so qualified name lookup can find it.
8846 DeclContext *Ctx = S->getEntity();
8847 if (Ctx && !Ctx->isFunctionOrMethod())
8850 // Otherwise, it is at block scope. The using-directives will affect lookup
8851 // only to the end of the scope.
8852 S->PushUsingDirective(UDir);
8856 Decl *Sema::ActOnUsingDeclaration(Scope *S,
8858 SourceLocation UsingLoc,
8859 SourceLocation TypenameLoc,
8861 UnqualifiedId &Name,
8862 SourceLocation EllipsisLoc,
8863 AttributeList *AttrList) {
8864 assert(S->getFlags() & Scope::DeclScope && "Invalid Scope.");
8867 Diag(Name.getLocStart(), diag::err_using_requires_qualname);
8871 switch (Name.getKind()) {
8872 case UnqualifiedId::IK_ImplicitSelfParam:
8873 case UnqualifiedId::IK_Identifier:
8874 case UnqualifiedId::IK_OperatorFunctionId:
8875 case UnqualifiedId::IK_LiteralOperatorId:
8876 case UnqualifiedId::IK_ConversionFunctionId:
8879 case UnqualifiedId::IK_ConstructorName:
8880 case UnqualifiedId::IK_ConstructorTemplateId:
8881 // C++11 inheriting constructors.
8882 Diag(Name.getLocStart(),
8883 getLangOpts().CPlusPlus11 ?
8884 diag::warn_cxx98_compat_using_decl_constructor :
8885 diag::err_using_decl_constructor)
8888 if (getLangOpts().CPlusPlus11) break;
8892 case UnqualifiedId::IK_DestructorName:
8893 Diag(Name.getLocStart(), diag::err_using_decl_destructor)
8897 case UnqualifiedId::IK_TemplateId:
8898 Diag(Name.getLocStart(), diag::err_using_decl_template_id)
8899 << SourceRange(Name.TemplateId->LAngleLoc, Name.TemplateId->RAngleLoc);
8902 case UnqualifiedId::IK_DeductionGuideName:
8903 llvm_unreachable("cannot parse qualified deduction guide name");
8906 DeclarationNameInfo TargetNameInfo = GetNameFromUnqualifiedId(Name);
8907 DeclarationName TargetName = TargetNameInfo.getName();
8911 // Warn about access declarations.
8912 if (UsingLoc.isInvalid()) {
8913 Diag(Name.getLocStart(),
8914 getLangOpts().CPlusPlus11 ? diag::err_access_decl
8915 : diag::warn_access_decl_deprecated)
8916 << FixItHint::CreateInsertion(SS.getRange().getBegin(), "using ");
8919 if (EllipsisLoc.isInvalid()) {
8920 if (DiagnoseUnexpandedParameterPack(SS, UPPC_UsingDeclaration) ||
8921 DiagnoseUnexpandedParameterPack(TargetNameInfo, UPPC_UsingDeclaration))
8924 if (!SS.getScopeRep()->containsUnexpandedParameterPack() &&
8925 !TargetNameInfo.containsUnexpandedParameterPack()) {
8926 Diag(EllipsisLoc, diag::err_pack_expansion_without_parameter_packs)
8927 << SourceRange(SS.getBeginLoc(), TargetNameInfo.getEndLoc());
8928 EllipsisLoc = SourceLocation();
8933 BuildUsingDeclaration(S, AS, UsingLoc, TypenameLoc.isValid(), TypenameLoc,
8934 SS, TargetNameInfo, EllipsisLoc, AttrList,
8935 /*IsInstantiation*/false);
8937 PushOnScopeChains(UD, S, /*AddToContext*/ false);
8942 /// \brief Determine whether a using declaration considers the given
8943 /// declarations as "equivalent", e.g., if they are redeclarations of
8944 /// the same entity or are both typedefs of the same type.
8946 IsEquivalentForUsingDecl(ASTContext &Context, NamedDecl *D1, NamedDecl *D2) {
8947 if (D1->getCanonicalDecl() == D2->getCanonicalDecl())
8950 if (TypedefNameDecl *TD1 = dyn_cast<TypedefNameDecl>(D1))
8951 if (TypedefNameDecl *TD2 = dyn_cast<TypedefNameDecl>(D2))
8952 return Context.hasSameType(TD1->getUnderlyingType(),
8953 TD2->getUnderlyingType());
8959 /// Determines whether to create a using shadow decl for a particular
8960 /// decl, given the set of decls existing prior to this using lookup.
8961 bool Sema::CheckUsingShadowDecl(UsingDecl *Using, NamedDecl *Orig,
8962 const LookupResult &Previous,
8963 UsingShadowDecl *&PrevShadow) {
8964 // Diagnose finding a decl which is not from a base class of the
8965 // current class. We do this now because there are cases where this
8966 // function will silently decide not to build a shadow decl, which
8967 // will pre-empt further diagnostics.
8969 // We don't need to do this in C++11 because we do the check once on
8972 // FIXME: diagnose the following if we care enough:
8973 // struct A { int foo; };
8974 // struct B : A { using A::foo; };
8975 // template <class T> struct C : A {};
8976 // template <class T> struct D : C<T> { using B::foo; } // <---
8977 // This is invalid (during instantiation) in C++03 because B::foo
8978 // resolves to the using decl in B, which is not a base class of D<T>.
8979 // We can't diagnose it immediately because C<T> is an unknown
8980 // specialization. The UsingShadowDecl in D<T> then points directly
8981 // to A::foo, which will look well-formed when we instantiate.
8982 // The right solution is to not collapse the shadow-decl chain.
8983 if (!getLangOpts().CPlusPlus11 && CurContext->isRecord()) {
8984 DeclContext *OrigDC = Orig->getDeclContext();
8986 // Handle enums and anonymous structs.
8987 if (isa<EnumDecl>(OrigDC)) OrigDC = OrigDC->getParent();
8988 CXXRecordDecl *OrigRec = cast<CXXRecordDecl>(OrigDC);
8989 while (OrigRec->isAnonymousStructOrUnion())
8990 OrigRec = cast<CXXRecordDecl>(OrigRec->getDeclContext());
8992 if (cast<CXXRecordDecl>(CurContext)->isProvablyNotDerivedFrom(OrigRec)) {
8993 if (OrigDC == CurContext) {
8994 Diag(Using->getLocation(),
8995 diag::err_using_decl_nested_name_specifier_is_current_class)
8996 << Using->getQualifierLoc().getSourceRange();
8997 Diag(Orig->getLocation(), diag::note_using_decl_target);
8998 Using->setInvalidDecl();
9002 Diag(Using->getQualifierLoc().getBeginLoc(),
9003 diag::err_using_decl_nested_name_specifier_is_not_base_class)
9004 << Using->getQualifier()
9005 << cast<CXXRecordDecl>(CurContext)
9006 << Using->getQualifierLoc().getSourceRange();
9007 Diag(Orig->getLocation(), diag::note_using_decl_target);
9008 Using->setInvalidDecl();
9013 if (Previous.empty()) return false;
9015 NamedDecl *Target = Orig;
9016 if (isa<UsingShadowDecl>(Target))
9017 Target = cast<UsingShadowDecl>(Target)->getTargetDecl();
9019 // If the target happens to be one of the previous declarations, we
9020 // don't have a conflict.
9022 // FIXME: but we might be increasing its access, in which case we
9023 // should redeclare it.
9024 NamedDecl *NonTag = nullptr, *Tag = nullptr;
9025 bool FoundEquivalentDecl = false;
9026 for (LookupResult::iterator I = Previous.begin(), E = Previous.end();
9028 NamedDecl *D = (*I)->getUnderlyingDecl();
9029 // We can have UsingDecls in our Previous results because we use the same
9030 // LookupResult for checking whether the UsingDecl itself is a valid
9032 if (isa<UsingDecl>(D) || isa<UsingPackDecl>(D))
9035 if (IsEquivalentForUsingDecl(Context, D, Target)) {
9036 if (UsingShadowDecl *Shadow = dyn_cast<UsingShadowDecl>(*I))
9037 PrevShadow = Shadow;
9038 FoundEquivalentDecl = true;
9039 } else if (isEquivalentInternalLinkageDeclaration(D, Target)) {
9040 // We don't conflict with an existing using shadow decl of an equivalent
9041 // declaration, but we're not a redeclaration of it.
9042 FoundEquivalentDecl = true;
9046 (isa<TagDecl>(D) ? Tag : NonTag) = D;
9049 if (FoundEquivalentDecl)
9052 if (FunctionDecl *FD = Target->getAsFunction()) {
9053 NamedDecl *OldDecl = nullptr;
9054 switch (CheckOverload(nullptr, FD, Previous, OldDecl,
9055 /*IsForUsingDecl*/ true)) {
9059 case Ovl_NonFunction:
9060 Diag(Using->getLocation(), diag::err_using_decl_conflict);
9063 // We found a decl with the exact signature.
9065 // If we're in a record, we want to hide the target, so we
9066 // return true (without a diagnostic) to tell the caller not to
9067 // build a shadow decl.
9068 if (CurContext->isRecord())
9071 // If we're not in a record, this is an error.
9072 Diag(Using->getLocation(), diag::err_using_decl_conflict);
9076 Diag(Target->getLocation(), diag::note_using_decl_target);
9077 Diag(OldDecl->getLocation(), diag::note_using_decl_conflict);
9078 Using->setInvalidDecl();
9082 // Target is not a function.
9084 if (isa<TagDecl>(Target)) {
9085 // No conflict between a tag and a non-tag.
9086 if (!Tag) return false;
9088 Diag(Using->getLocation(), diag::err_using_decl_conflict);
9089 Diag(Target->getLocation(), diag::note_using_decl_target);
9090 Diag(Tag->getLocation(), diag::note_using_decl_conflict);
9091 Using->setInvalidDecl();
9095 // No conflict between a tag and a non-tag.
9096 if (!NonTag) return false;
9098 Diag(Using->getLocation(), diag::err_using_decl_conflict);
9099 Diag(Target->getLocation(), diag::note_using_decl_target);
9100 Diag(NonTag->getLocation(), diag::note_using_decl_conflict);
9101 Using->setInvalidDecl();
9105 /// Determine whether a direct base class is a virtual base class.
9106 static bool isVirtualDirectBase(CXXRecordDecl *Derived, CXXRecordDecl *Base) {
9107 if (!Derived->getNumVBases())
9109 for (auto &B : Derived->bases())
9110 if (B.getType()->getAsCXXRecordDecl() == Base)
9111 return B.isVirtual();
9112 llvm_unreachable("not a direct base class");
9115 /// Builds a shadow declaration corresponding to a 'using' declaration.
9116 UsingShadowDecl *Sema::BuildUsingShadowDecl(Scope *S,
9119 UsingShadowDecl *PrevDecl) {
9120 // If we resolved to another shadow declaration, just coalesce them.
9121 NamedDecl *Target = Orig;
9122 if (isa<UsingShadowDecl>(Target)) {
9123 Target = cast<UsingShadowDecl>(Target)->getTargetDecl();
9124 assert(!isa<UsingShadowDecl>(Target) && "nested shadow declaration");
9127 NamedDecl *NonTemplateTarget = Target;
9128 if (auto *TargetTD = dyn_cast<TemplateDecl>(Target))
9129 NonTemplateTarget = TargetTD->getTemplatedDecl();
9131 UsingShadowDecl *Shadow;
9132 if (isa<CXXConstructorDecl>(NonTemplateTarget)) {
9133 bool IsVirtualBase =
9134 isVirtualDirectBase(cast<CXXRecordDecl>(CurContext),
9135 UD->getQualifier()->getAsRecordDecl());
9136 Shadow = ConstructorUsingShadowDecl::Create(
9137 Context, CurContext, UD->getLocation(), UD, Orig, IsVirtualBase);
9139 Shadow = UsingShadowDecl::Create(Context, CurContext, UD->getLocation(), UD,
9142 UD->addShadowDecl(Shadow);
9144 Shadow->setAccess(UD->getAccess());
9145 if (Orig->isInvalidDecl() || UD->isInvalidDecl())
9146 Shadow->setInvalidDecl();
9148 Shadow->setPreviousDecl(PrevDecl);
9151 PushOnScopeChains(Shadow, S);
9153 CurContext->addDecl(Shadow);
9159 /// Hides a using shadow declaration. This is required by the current
9160 /// using-decl implementation when a resolvable using declaration in a
9161 /// class is followed by a declaration which would hide or override
9162 /// one or more of the using decl's targets; for example:
9164 /// struct Base { void foo(int); };
9165 /// struct Derived : Base {
9166 /// using Base::foo;
9170 /// The governing language is C++03 [namespace.udecl]p12:
9172 /// When a using-declaration brings names from a base class into a
9173 /// derived class scope, member functions in the derived class
9174 /// override and/or hide member functions with the same name and
9175 /// parameter types in a base class (rather than conflicting).
9177 /// There are two ways to implement this:
9178 /// (1) optimistically create shadow decls when they're not hidden
9179 /// by existing declarations, or
9180 /// (2) don't create any shadow decls (or at least don't make them
9181 /// visible) until we've fully parsed/instantiated the class.
9182 /// The problem with (1) is that we might have to retroactively remove
9183 /// a shadow decl, which requires several O(n) operations because the
9184 /// decl structures are (very reasonably) not designed for removal.
9185 /// (2) avoids this but is very fiddly and phase-dependent.
9186 void Sema::HideUsingShadowDecl(Scope *S, UsingShadowDecl *Shadow) {
9187 if (Shadow->getDeclName().getNameKind() ==
9188 DeclarationName::CXXConversionFunctionName)
9189 cast<CXXRecordDecl>(Shadow->getDeclContext())->removeConversion(Shadow);
9191 // Remove it from the DeclContext...
9192 Shadow->getDeclContext()->removeDecl(Shadow);
9194 // ...and the scope, if applicable...
9196 S->RemoveDecl(Shadow);
9197 IdResolver.RemoveDecl(Shadow);
9200 // ...and the using decl.
9201 Shadow->getUsingDecl()->removeShadowDecl(Shadow);
9203 // TODO: complain somehow if Shadow was used. It shouldn't
9204 // be possible for this to happen, because...?
9207 /// Find the base specifier for a base class with the given type.
9208 static CXXBaseSpecifier *findDirectBaseWithType(CXXRecordDecl *Derived,
9209 QualType DesiredBase,
9210 bool &AnyDependentBases) {
9211 // Check whether the named type is a direct base class.
9212 CanQualType CanonicalDesiredBase = DesiredBase->getCanonicalTypeUnqualified();
9213 for (auto &Base : Derived->bases()) {
9214 CanQualType BaseType = Base.getType()->getCanonicalTypeUnqualified();
9215 if (CanonicalDesiredBase == BaseType)
9217 if (BaseType->isDependentType())
9218 AnyDependentBases = true;
9224 class UsingValidatorCCC : public CorrectionCandidateCallback {
9226 UsingValidatorCCC(bool HasTypenameKeyword, bool IsInstantiation,
9227 NestedNameSpecifier *NNS, CXXRecordDecl *RequireMemberOf)
9228 : HasTypenameKeyword(HasTypenameKeyword),
9229 IsInstantiation(IsInstantiation), OldNNS(NNS),
9230 RequireMemberOf(RequireMemberOf) {}
9232 bool ValidateCandidate(const TypoCorrection &Candidate) override {
9233 NamedDecl *ND = Candidate.getCorrectionDecl();
9235 // Keywords are not valid here.
9236 if (!ND || isa<NamespaceDecl>(ND))
9239 // Completely unqualified names are invalid for a 'using' declaration.
9240 if (Candidate.WillReplaceSpecifier() && !Candidate.getCorrectionSpecifier())
9243 // FIXME: Don't correct to a name that CheckUsingDeclRedeclaration would
9246 if (RequireMemberOf) {
9247 auto *FoundRecord = dyn_cast<CXXRecordDecl>(ND);
9248 if (FoundRecord && FoundRecord->isInjectedClassName()) {
9249 // No-one ever wants a using-declaration to name an injected-class-name
9250 // of a base class, unless they're declaring an inheriting constructor.
9251 ASTContext &Ctx = ND->getASTContext();
9252 if (!Ctx.getLangOpts().CPlusPlus11)
9254 QualType FoundType = Ctx.getRecordType(FoundRecord);
9256 // Check that the injected-class-name is named as a member of its own
9257 // type; we don't want to suggest 'using Derived::Base;', since that
9258 // means something else.
9259 NestedNameSpecifier *Specifier =
9260 Candidate.WillReplaceSpecifier()
9261 ? Candidate.getCorrectionSpecifier()
9263 if (!Specifier->getAsType() ||
9264 !Ctx.hasSameType(QualType(Specifier->getAsType(), 0), FoundType))
9267 // Check that this inheriting constructor declaration actually names a
9268 // direct base class of the current class.
9269 bool AnyDependentBases = false;
9270 if (!findDirectBaseWithType(RequireMemberOf,
9271 Ctx.getRecordType(FoundRecord),
9272 AnyDependentBases) &&
9276 auto *RD = dyn_cast<CXXRecordDecl>(ND->getDeclContext());
9277 if (!RD || RequireMemberOf->isProvablyNotDerivedFrom(RD))
9280 // FIXME: Check that the base class member is accessible?
9283 auto *FoundRecord = dyn_cast<CXXRecordDecl>(ND);
9284 if (FoundRecord && FoundRecord->isInjectedClassName())
9288 if (isa<TypeDecl>(ND))
9289 return HasTypenameKeyword || !IsInstantiation;
9291 return !HasTypenameKeyword;
9295 bool HasTypenameKeyword;
9296 bool IsInstantiation;
9297 NestedNameSpecifier *OldNNS;
9298 CXXRecordDecl *RequireMemberOf;
9300 } // end anonymous namespace
9302 /// Builds a using declaration.
9304 /// \param IsInstantiation - Whether this call arises from an
9305 /// instantiation of an unresolved using declaration. We treat
9306 /// the lookup differently for these declarations.
9307 NamedDecl *Sema::BuildUsingDeclaration(Scope *S, AccessSpecifier AS,
9308 SourceLocation UsingLoc,
9309 bool HasTypenameKeyword,
9310 SourceLocation TypenameLoc,
9312 DeclarationNameInfo NameInfo,
9313 SourceLocation EllipsisLoc,
9314 AttributeList *AttrList,
9315 bool IsInstantiation) {
9316 assert(!SS.isInvalid() && "Invalid CXXScopeSpec.");
9317 SourceLocation IdentLoc = NameInfo.getLoc();
9318 assert(IdentLoc.isValid() && "Invalid TargetName location.");
9320 // FIXME: We ignore attributes for now.
9322 // For an inheriting constructor declaration, the name of the using
9323 // declaration is the name of a constructor in this class, not in the
9325 DeclarationNameInfo UsingName = NameInfo;
9326 if (UsingName.getName().getNameKind() == DeclarationName::CXXConstructorName)
9327 if (auto *RD = dyn_cast<CXXRecordDecl>(CurContext))
9328 UsingName.setName(Context.DeclarationNames.getCXXConstructorName(
9329 Context.getCanonicalType(Context.getRecordType(RD))));
9331 // Do the redeclaration lookup in the current scope.
9332 LookupResult Previous(*this, UsingName, LookupUsingDeclName,
9334 Previous.setHideTags(false);
9336 LookupName(Previous, S);
9338 // It is really dumb that we have to do this.
9339 LookupResult::Filter F = Previous.makeFilter();
9340 while (F.hasNext()) {
9341 NamedDecl *D = F.next();
9342 if (!isDeclInScope(D, CurContext, S))
9344 // If we found a local extern declaration that's not ordinarily visible,
9345 // and this declaration is being added to a non-block scope, ignore it.
9346 // We're only checking for scope conflicts here, not also for violations
9347 // of the linkage rules.
9348 else if (!CurContext->isFunctionOrMethod() && D->isLocalExternDecl() &&
9349 !(D->getIdentifierNamespace() & Decl::IDNS_Ordinary))
9354 assert(IsInstantiation && "no scope in non-instantiation");
9355 if (CurContext->isRecord())
9356 LookupQualifiedName(Previous, CurContext);
9358 // No redeclaration check is needed here; in non-member contexts we
9359 // diagnosed all possible conflicts with other using-declarations when
9360 // building the template:
9362 // For a dependent non-type using declaration, the only valid case is
9363 // if we instantiate to a single enumerator. We check for conflicts
9364 // between shadow declarations we introduce, and we check in the template
9365 // definition for conflicts between a non-type using declaration and any
9366 // other declaration, which together covers all cases.
9368 // A dependent typename using declaration will never successfully
9369 // instantiate, since it will always name a class member, so we reject
9370 // that in the template definition.
9374 // Check for invalid redeclarations.
9375 if (CheckUsingDeclRedeclaration(UsingLoc, HasTypenameKeyword,
9376 SS, IdentLoc, Previous))
9379 // Check for bad qualifiers.
9380 if (CheckUsingDeclQualifier(UsingLoc, HasTypenameKeyword, SS, NameInfo,
9384 DeclContext *LookupContext = computeDeclContext(SS);
9386 NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
9387 if (!LookupContext || EllipsisLoc.isValid()) {
9388 if (HasTypenameKeyword) {
9389 // FIXME: not all declaration name kinds are legal here
9390 D = UnresolvedUsingTypenameDecl::Create(Context, CurContext,
9391 UsingLoc, TypenameLoc,
9393 IdentLoc, NameInfo.getName(),
9396 D = UnresolvedUsingValueDecl::Create(Context, CurContext, UsingLoc,
9397 QualifierLoc, NameInfo, EllipsisLoc);
9400 CurContext->addDecl(D);
9404 auto Build = [&](bool Invalid) {
9406 UsingDecl::Create(Context, CurContext, UsingLoc, QualifierLoc,
9407 UsingName, HasTypenameKeyword);
9409 CurContext->addDecl(UD);
9410 UD->setInvalidDecl(Invalid);
9413 auto BuildInvalid = [&]{ return Build(true); };
9414 auto BuildValid = [&]{ return Build(false); };
9416 if (RequireCompleteDeclContext(SS, LookupContext))
9417 return BuildInvalid();
9419 // Look up the target name.
9420 LookupResult R(*this, NameInfo, LookupOrdinaryName);
9422 // Unlike most lookups, we don't always want to hide tag
9423 // declarations: tag names are visible through the using declaration
9424 // even if hidden by ordinary names, *except* in a dependent context
9425 // where it's important for the sanity of two-phase lookup.
9426 if (!IsInstantiation)
9427 R.setHideTags(false);
9429 // For the purposes of this lookup, we have a base object type
9430 // equal to that of the current context.
9431 if (CurContext->isRecord()) {
9432 R.setBaseObjectType(
9433 Context.getTypeDeclType(cast<CXXRecordDecl>(CurContext)));
9436 LookupQualifiedName(R, LookupContext);
9438 // Try to correct typos if possible. If constructor name lookup finds no
9439 // results, that means the named class has no explicit constructors, and we
9440 // suppressed declaring implicit ones (probably because it's dependent or
9443 NameInfo.getName().getNameKind() != DeclarationName::CXXConstructorName) {
9444 // HACK: Work around a bug in libstdc++'s detection of ::gets. Sometimes
9445 // it will believe that glibc provides a ::gets in cases where it does not,
9446 // and will try to pull it into namespace std with a using-declaration.
9447 // Just ignore the using-declaration in that case.
9448 auto *II = NameInfo.getName().getAsIdentifierInfo();
9449 if (getLangOpts().CPlusPlus14 && II && II->isStr("gets") &&
9450 CurContext->isStdNamespace() &&
9451 isa<TranslationUnitDecl>(LookupContext) &&
9452 getSourceManager().isInSystemHeader(UsingLoc))
9454 if (TypoCorrection Corrected = CorrectTypo(
9455 R.getLookupNameInfo(), R.getLookupKind(), S, &SS,
9456 llvm::make_unique<UsingValidatorCCC>(
9457 HasTypenameKeyword, IsInstantiation, SS.getScopeRep(),
9458 dyn_cast<CXXRecordDecl>(CurContext)),
9459 CTK_ErrorRecovery)) {
9460 // We reject candidates where DroppedSpecifier == true, hence the
9461 // literal '0' below.
9462 diagnoseTypo(Corrected, PDiag(diag::err_no_member_suggest)
9463 << NameInfo.getName() << LookupContext << 0
9466 // If we picked a correction with no attached Decl we can't do anything
9467 // useful with it, bail out.
9468 NamedDecl *ND = Corrected.getCorrectionDecl();
9470 return BuildInvalid();
9472 // If we corrected to an inheriting constructor, handle it as one.
9473 auto *RD = dyn_cast<CXXRecordDecl>(ND);
9474 if (RD && RD->isInjectedClassName()) {
9475 // The parent of the injected class name is the class itself.
9476 RD = cast<CXXRecordDecl>(RD->getParent());
9478 // Fix up the information we'll use to build the using declaration.
9479 if (Corrected.WillReplaceSpecifier()) {
9480 NestedNameSpecifierLocBuilder Builder;
9481 Builder.MakeTrivial(Context, Corrected.getCorrectionSpecifier(),
9482 QualifierLoc.getSourceRange());
9483 QualifierLoc = Builder.getWithLocInContext(Context);
9486 // In this case, the name we introduce is the name of a derived class
9488 auto *CurClass = cast<CXXRecordDecl>(CurContext);
9489 UsingName.setName(Context.DeclarationNames.getCXXConstructorName(
9490 Context.getCanonicalType(Context.getRecordType(CurClass))));
9491 UsingName.setNamedTypeInfo(nullptr);
9492 for (auto *Ctor : LookupConstructors(RD))
9496 // FIXME: Pick up all the declarations if we found an overloaded
9498 UsingName.setName(ND->getDeclName());
9502 Diag(IdentLoc, diag::err_no_member)
9503 << NameInfo.getName() << LookupContext << SS.getRange();
9504 return BuildInvalid();
9508 if (R.isAmbiguous())
9509 return BuildInvalid();
9511 if (HasTypenameKeyword) {
9512 // If we asked for a typename and got a non-type decl, error out.
9513 if (!R.getAsSingle<TypeDecl>()) {
9514 Diag(IdentLoc, diag::err_using_typename_non_type);
9515 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
9516 Diag((*I)->getUnderlyingDecl()->getLocation(),
9517 diag::note_using_decl_target);
9518 return BuildInvalid();
9521 // If we asked for a non-typename and we got a type, error out,
9522 // but only if this is an instantiation of an unresolved using
9523 // decl. Otherwise just silently find the type name.
9524 if (IsInstantiation && R.getAsSingle<TypeDecl>()) {
9525 Diag(IdentLoc, diag::err_using_dependent_value_is_type);
9526 Diag(R.getFoundDecl()->getLocation(), diag::note_using_decl_target);
9527 return BuildInvalid();
9531 // C++14 [namespace.udecl]p6:
9532 // A using-declaration shall not name a namespace.
9533 if (R.getAsSingle<NamespaceDecl>()) {
9534 Diag(IdentLoc, diag::err_using_decl_can_not_refer_to_namespace)
9536 return BuildInvalid();
9539 // C++14 [namespace.udecl]p7:
9540 // A using-declaration shall not name a scoped enumerator.
9541 if (auto *ED = R.getAsSingle<EnumConstantDecl>()) {
9542 if (cast<EnumDecl>(ED->getDeclContext())->isScoped()) {
9543 Diag(IdentLoc, diag::err_using_decl_can_not_refer_to_scoped_enum)
9545 return BuildInvalid();
9549 UsingDecl *UD = BuildValid();
9551 // Some additional rules apply to inheriting constructors.
9552 if (UsingName.getName().getNameKind() ==
9553 DeclarationName::CXXConstructorName) {
9554 // Suppress access diagnostics; the access check is instead performed at the
9555 // point of use for an inheriting constructor.
9556 R.suppressDiagnostics();
9557 if (CheckInheritingConstructorUsingDecl(UD))
9561 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) {
9562 UsingShadowDecl *PrevDecl = nullptr;
9563 if (!CheckUsingShadowDecl(UD, *I, Previous, PrevDecl))
9564 BuildUsingShadowDecl(S, UD, *I, PrevDecl);
9570 NamedDecl *Sema::BuildUsingPackDecl(NamedDecl *InstantiatedFrom,
9571 ArrayRef<NamedDecl *> Expansions) {
9572 assert(isa<UnresolvedUsingValueDecl>(InstantiatedFrom) ||
9573 isa<UnresolvedUsingTypenameDecl>(InstantiatedFrom) ||
9574 isa<UsingPackDecl>(InstantiatedFrom));
9577 UsingPackDecl::Create(Context, CurContext, InstantiatedFrom, Expansions);
9578 UPD->setAccess(InstantiatedFrom->getAccess());
9579 CurContext->addDecl(UPD);
9583 /// Additional checks for a using declaration referring to a constructor name.
9584 bool Sema::CheckInheritingConstructorUsingDecl(UsingDecl *UD) {
9585 assert(!UD->hasTypename() && "expecting a constructor name");
9587 const Type *SourceType = UD->getQualifier()->getAsType();
9588 assert(SourceType &&
9589 "Using decl naming constructor doesn't have type in scope spec.");
9590 CXXRecordDecl *TargetClass = cast<CXXRecordDecl>(CurContext);
9592 // Check whether the named type is a direct base class.
9593 bool AnyDependentBases = false;
9594 auto *Base = findDirectBaseWithType(TargetClass, QualType(SourceType, 0),
9596 if (!Base && !AnyDependentBases) {
9597 Diag(UD->getUsingLoc(),
9598 diag::err_using_decl_constructor_not_in_direct_base)
9599 << UD->getNameInfo().getSourceRange()
9600 << QualType(SourceType, 0) << TargetClass;
9601 UD->setInvalidDecl();
9606 Base->setInheritConstructors();
9611 /// Checks that the given using declaration is not an invalid
9612 /// redeclaration. Note that this is checking only for the using decl
9613 /// itself, not for any ill-formedness among the UsingShadowDecls.
9614 bool Sema::CheckUsingDeclRedeclaration(SourceLocation UsingLoc,
9615 bool HasTypenameKeyword,
9616 const CXXScopeSpec &SS,
9617 SourceLocation NameLoc,
9618 const LookupResult &Prev) {
9619 NestedNameSpecifier *Qual = SS.getScopeRep();
9621 // C++03 [namespace.udecl]p8:
9622 // C++0x [namespace.udecl]p10:
9623 // A using-declaration is a declaration and can therefore be used
9624 // repeatedly where (and only where) multiple declarations are
9627 // That's in non-member contexts.
9628 if (!CurContext->getRedeclContext()->isRecord()) {
9629 // A dependent qualifier outside a class can only ever resolve to an
9630 // enumeration type. Therefore it conflicts with any other non-type
9631 // declaration in the same scope.
9632 // FIXME: How should we check for dependent type-type conflicts at block
9634 if (Qual->isDependent() && !HasTypenameKeyword) {
9635 for (auto *D : Prev) {
9636 if (!isa<TypeDecl>(D) && !isa<UsingDecl>(D) && !isa<UsingPackDecl>(D)) {
9637 bool OldCouldBeEnumerator =
9638 isa<UnresolvedUsingValueDecl>(D) || isa<EnumConstantDecl>(D);
9640 OldCouldBeEnumerator ? diag::err_redefinition
9641 : diag::err_redefinition_different_kind)
9642 << Prev.getLookupName();
9643 Diag(D->getLocation(), diag::note_previous_definition);
9651 for (LookupResult::iterator I = Prev.begin(), E = Prev.end(); I != E; ++I) {
9655 NestedNameSpecifier *DQual;
9656 if (UsingDecl *UD = dyn_cast<UsingDecl>(D)) {
9657 DTypename = UD->hasTypename();
9658 DQual = UD->getQualifier();
9659 } else if (UnresolvedUsingValueDecl *UD
9660 = dyn_cast<UnresolvedUsingValueDecl>(D)) {
9662 DQual = UD->getQualifier();
9663 } else if (UnresolvedUsingTypenameDecl *UD
9664 = dyn_cast<UnresolvedUsingTypenameDecl>(D)) {
9666 DQual = UD->getQualifier();
9669 // using decls differ if one says 'typename' and the other doesn't.
9670 // FIXME: non-dependent using decls?
9671 if (HasTypenameKeyword != DTypename) continue;
9673 // using decls differ if they name different scopes (but note that
9674 // template instantiation can cause this check to trigger when it
9675 // didn't before instantiation).
9676 if (Context.getCanonicalNestedNameSpecifier(Qual) !=
9677 Context.getCanonicalNestedNameSpecifier(DQual))
9680 Diag(NameLoc, diag::err_using_decl_redeclaration) << SS.getRange();
9681 Diag(D->getLocation(), diag::note_using_decl) << 1;
9689 /// Checks that the given nested-name qualifier used in a using decl
9690 /// in the current context is appropriately related to the current
9691 /// scope. If an error is found, diagnoses it and returns true.
9692 bool Sema::CheckUsingDeclQualifier(SourceLocation UsingLoc,
9694 const CXXScopeSpec &SS,
9695 const DeclarationNameInfo &NameInfo,
9696 SourceLocation NameLoc) {
9697 DeclContext *NamedContext = computeDeclContext(SS);
9699 if (!CurContext->isRecord()) {
9700 // C++03 [namespace.udecl]p3:
9701 // C++0x [namespace.udecl]p8:
9702 // A using-declaration for a class member shall be a member-declaration.
9704 // If we weren't able to compute a valid scope, it might validly be a
9705 // dependent class scope or a dependent enumeration unscoped scope. If
9706 // we have a 'typename' keyword, the scope must resolve to a class type.
9707 if ((HasTypename && !NamedContext) ||
9708 (NamedContext && NamedContext->getRedeclContext()->isRecord())) {
9709 auto *RD = NamedContext
9710 ? cast<CXXRecordDecl>(NamedContext->getRedeclContext())
9712 if (RD && RequireCompleteDeclContext(const_cast<CXXScopeSpec&>(SS), RD))
9715 Diag(NameLoc, diag::err_using_decl_can_not_refer_to_class_member)
9718 // If we have a complete, non-dependent source type, try to suggest a
9719 // way to get the same effect.
9723 // Find what this using-declaration was referring to.
9724 LookupResult R(*this, NameInfo, LookupOrdinaryName);
9725 R.setHideTags(false);
9726 R.suppressDiagnostics();
9727 LookupQualifiedName(R, RD);
9729 if (R.getAsSingle<TypeDecl>()) {
9730 if (getLangOpts().CPlusPlus11) {
9731 // Convert 'using X::Y;' to 'using Y = X::Y;'.
9732 Diag(SS.getBeginLoc(), diag::note_using_decl_class_member_workaround)
9733 << 0 // alias declaration
9734 << FixItHint::CreateInsertion(SS.getBeginLoc(),
9735 NameInfo.getName().getAsString() +
9738 // Convert 'using X::Y;' to 'typedef X::Y Y;'.
9739 SourceLocation InsertLoc =
9740 getLocForEndOfToken(NameInfo.getLocEnd());
9741 Diag(InsertLoc, diag::note_using_decl_class_member_workaround)
9742 << 1 // typedef declaration
9743 << FixItHint::CreateReplacement(UsingLoc, "typedef")
9744 << FixItHint::CreateInsertion(
9745 InsertLoc, " " + NameInfo.getName().getAsString());
9747 } else if (R.getAsSingle<VarDecl>()) {
9748 // Don't provide a fixit outside C++11 mode; we don't want to suggest
9749 // repeating the type of the static data member here.
9751 if (getLangOpts().CPlusPlus11) {
9752 // Convert 'using X::Y;' to 'auto &Y = X::Y;'.
9753 FixIt = FixItHint::CreateReplacement(
9754 UsingLoc, "auto &" + NameInfo.getName().getAsString() + " = ");
9757 Diag(UsingLoc, diag::note_using_decl_class_member_workaround)
9758 << 2 // reference declaration
9760 } else if (R.getAsSingle<EnumConstantDecl>()) {
9761 // Don't provide a fixit outside C++11 mode; we don't want to suggest
9762 // repeating the type of the enumeration here, and we can't do so if
9763 // the type is anonymous.
9765 if (getLangOpts().CPlusPlus11) {
9766 // Convert 'using X::Y;' to 'auto &Y = X::Y;'.
9767 FixIt = FixItHint::CreateReplacement(
9769 "constexpr auto " + NameInfo.getName().getAsString() + " = ");
9772 Diag(UsingLoc, diag::note_using_decl_class_member_workaround)
9773 << (getLangOpts().CPlusPlus11 ? 4 : 3) // const[expr] variable
9779 // Otherwise, this might be valid.
9783 // The current scope is a record.
9785 // If the named context is dependent, we can't decide much.
9786 if (!NamedContext) {
9787 // FIXME: in C++0x, we can diagnose if we can prove that the
9788 // nested-name-specifier does not refer to a base class, which is
9789 // still possible in some cases.
9791 // Otherwise we have to conservatively report that things might be
9796 if (!NamedContext->isRecord()) {
9797 // Ideally this would point at the last name in the specifier,
9798 // but we don't have that level of source info.
9799 Diag(SS.getRange().getBegin(),
9800 diag::err_using_decl_nested_name_specifier_is_not_class)
9801 << SS.getScopeRep() << SS.getRange();
9805 if (!NamedContext->isDependentContext() &&
9806 RequireCompleteDeclContext(const_cast<CXXScopeSpec&>(SS), NamedContext))
9809 if (getLangOpts().CPlusPlus11) {
9810 // C++11 [namespace.udecl]p3:
9811 // In a using-declaration used as a member-declaration, the
9812 // nested-name-specifier shall name a base class of the class
9815 if (cast<CXXRecordDecl>(CurContext)->isProvablyNotDerivedFrom(
9816 cast<CXXRecordDecl>(NamedContext))) {
9817 if (CurContext == NamedContext) {
9819 diag::err_using_decl_nested_name_specifier_is_current_class)
9824 if (!cast<CXXRecordDecl>(NamedContext)->isInvalidDecl()) {
9825 Diag(SS.getRange().getBegin(),
9826 diag::err_using_decl_nested_name_specifier_is_not_base_class)
9828 << cast<CXXRecordDecl>(CurContext)
9837 // C++03 [namespace.udecl]p4:
9838 // A using-declaration used as a member-declaration shall refer
9839 // to a member of a base class of the class being defined [etc.].
9841 // Salient point: SS doesn't have to name a base class as long as
9842 // lookup only finds members from base classes. Therefore we can
9843 // diagnose here only if we can prove that that can't happen,
9844 // i.e. if the class hierarchies provably don't intersect.
9846 // TODO: it would be nice if "definitely valid" results were cached
9847 // in the UsingDecl and UsingShadowDecl so that these checks didn't
9848 // need to be repeated.
9850 llvm::SmallPtrSet<const CXXRecordDecl *, 4> Bases;
9851 auto Collect = [&Bases](const CXXRecordDecl *Base) {
9856 // Collect all bases. Return false if we find a dependent base.
9857 if (!cast<CXXRecordDecl>(CurContext)->forallBases(Collect))
9860 // Returns true if the base is dependent or is one of the accumulated base
9862 auto IsNotBase = [&Bases](const CXXRecordDecl *Base) {
9863 return !Bases.count(Base);
9866 // Return false if the class has a dependent base or if it or one
9867 // of its bases is present in the base set of the current context.
9868 if (Bases.count(cast<CXXRecordDecl>(NamedContext)) ||
9869 !cast<CXXRecordDecl>(NamedContext)->forallBases(IsNotBase))
9872 Diag(SS.getRange().getBegin(),
9873 diag::err_using_decl_nested_name_specifier_is_not_base_class)
9875 << cast<CXXRecordDecl>(CurContext)
9881 Decl *Sema::ActOnAliasDeclaration(Scope *S,
9883 MultiTemplateParamsArg TemplateParamLists,
9884 SourceLocation UsingLoc,
9885 UnqualifiedId &Name,
9886 AttributeList *AttrList,
9888 Decl *DeclFromDeclSpec) {
9889 // Skip up to the relevant declaration scope.
9890 while (S->isTemplateParamScope())
9892 assert((S->getFlags() & Scope::DeclScope) &&
9893 "got alias-declaration outside of declaration scope");
9895 if (Type.isInvalid())
9898 bool Invalid = false;
9899 DeclarationNameInfo NameInfo = GetNameFromUnqualifiedId(Name);
9900 TypeSourceInfo *TInfo = nullptr;
9901 GetTypeFromParser(Type.get(), &TInfo);
9903 if (DiagnoseClassNameShadow(CurContext, NameInfo))
9906 if (DiagnoseUnexpandedParameterPack(Name.StartLocation, TInfo,
9907 UPPC_DeclarationType)) {
9909 TInfo = Context.getTrivialTypeSourceInfo(Context.IntTy,
9910 TInfo->getTypeLoc().getBeginLoc());
9913 LookupResult Previous(*this, NameInfo, LookupOrdinaryName, ForRedeclaration);
9914 LookupName(Previous, S);
9916 // Warn about shadowing the name of a template parameter.
9917 if (Previous.isSingleResult() &&
9918 Previous.getFoundDecl()->isTemplateParameter()) {
9919 DiagnoseTemplateParameterShadow(Name.StartLocation,Previous.getFoundDecl());
9923 assert(Name.Kind == UnqualifiedId::IK_Identifier &&
9924 "name in alias declaration must be an identifier");
9925 TypeAliasDecl *NewTD = TypeAliasDecl::Create(Context, CurContext, UsingLoc,
9927 Name.Identifier, TInfo);
9929 NewTD->setAccess(AS);
9932 NewTD->setInvalidDecl();
9934 ProcessDeclAttributeList(S, NewTD, AttrList);
9935 AddPragmaAttributes(S, NewTD);
9937 CheckTypedefForVariablyModifiedType(S, NewTD);
9938 Invalid |= NewTD->isInvalidDecl();
9940 bool Redeclaration = false;
9943 if (TemplateParamLists.size()) {
9944 TypeAliasTemplateDecl *OldDecl = nullptr;
9945 TemplateParameterList *OldTemplateParams = nullptr;
9947 if (TemplateParamLists.size() != 1) {
9948 Diag(UsingLoc, diag::err_alias_template_extra_headers)
9949 << SourceRange(TemplateParamLists[1]->getTemplateLoc(),
9950 TemplateParamLists[TemplateParamLists.size()-1]->getRAngleLoc());
9952 TemplateParameterList *TemplateParams = TemplateParamLists[0];
9954 // Check that we can declare a template here.
9955 if (CheckTemplateDeclScope(S, TemplateParams))
9958 // Only consider previous declarations in the same scope.
9959 FilterLookupForScope(Previous, CurContext, S, /*ConsiderLinkage*/false,
9960 /*ExplicitInstantiationOrSpecialization*/false);
9961 if (!Previous.empty()) {
9962 Redeclaration = true;
9964 OldDecl = Previous.getAsSingle<TypeAliasTemplateDecl>();
9965 if (!OldDecl && !Invalid) {
9966 Diag(UsingLoc, diag::err_redefinition_different_kind)
9969 NamedDecl *OldD = Previous.getRepresentativeDecl();
9970 if (OldD->getLocation().isValid())
9971 Diag(OldD->getLocation(), diag::note_previous_definition);
9976 if (!Invalid && OldDecl && !OldDecl->isInvalidDecl()) {
9977 if (TemplateParameterListsAreEqual(TemplateParams,
9978 OldDecl->getTemplateParameters(),
9981 OldTemplateParams = OldDecl->getTemplateParameters();
9985 TypeAliasDecl *OldTD = OldDecl->getTemplatedDecl();
9987 !Context.hasSameType(OldTD->getUnderlyingType(),
9988 NewTD->getUnderlyingType())) {
9989 // FIXME: The C++0x standard does not clearly say this is ill-formed,
9990 // but we can't reasonably accept it.
9991 Diag(NewTD->getLocation(), diag::err_redefinition_different_typedef)
9992 << 2 << NewTD->getUnderlyingType() << OldTD->getUnderlyingType();
9993 if (OldTD->getLocation().isValid())
9994 Diag(OldTD->getLocation(), diag::note_previous_definition);
10000 // Merge any previous default template arguments into our parameters,
10001 // and check the parameter list.
10002 if (CheckTemplateParameterList(TemplateParams, OldTemplateParams,
10003 TPC_TypeAliasTemplate))
10006 TypeAliasTemplateDecl *NewDecl =
10007 TypeAliasTemplateDecl::Create(Context, CurContext, UsingLoc,
10008 Name.Identifier, TemplateParams,
10010 NewTD->setDescribedAliasTemplate(NewDecl);
10012 NewDecl->setAccess(AS);
10015 NewDecl->setInvalidDecl();
10017 NewDecl->setPreviousDecl(OldDecl);
10021 if (auto *TD = dyn_cast_or_null<TagDecl>(DeclFromDeclSpec)) {
10022 setTagNameForLinkagePurposes(TD, NewTD);
10023 handleTagNumbering(TD, S);
10025 ActOnTypedefNameDecl(S, CurContext, NewTD, Previous, Redeclaration);
10029 PushOnScopeChains(NewND, S);
10030 ActOnDocumentableDecl(NewND);
10034 Decl *Sema::ActOnNamespaceAliasDef(Scope *S, SourceLocation NamespaceLoc,
10035 SourceLocation AliasLoc,
10036 IdentifierInfo *Alias, CXXScopeSpec &SS,
10037 SourceLocation IdentLoc,
10038 IdentifierInfo *Ident) {
10040 // Lookup the namespace name.
10041 LookupResult R(*this, Ident, IdentLoc, LookupNamespaceName);
10042 LookupParsedName(R, S, &SS);
10044 if (R.isAmbiguous())
10048 if (!TryNamespaceTypoCorrection(*this, R, S, SS, IdentLoc, Ident)) {
10049 Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange();
10053 assert(!R.isAmbiguous() && !R.empty());
10054 NamedDecl *ND = R.getRepresentativeDecl();
10056 // Check if we have a previous declaration with the same name.
10057 LookupResult PrevR(*this, Alias, AliasLoc, LookupOrdinaryName,
10059 LookupName(PrevR, S);
10061 // Check we're not shadowing a template parameter.
10062 if (PrevR.isSingleResult() && PrevR.getFoundDecl()->isTemplateParameter()) {
10063 DiagnoseTemplateParameterShadow(AliasLoc, PrevR.getFoundDecl());
10067 // Filter out any other lookup result from an enclosing scope.
10068 FilterLookupForScope(PrevR, CurContext, S, /*ConsiderLinkage*/false,
10069 /*AllowInlineNamespace*/false);
10071 // Find the previous declaration and check that we can redeclare it.
10072 NamespaceAliasDecl *Prev = nullptr;
10073 if (PrevR.isSingleResult()) {
10074 NamedDecl *PrevDecl = PrevR.getRepresentativeDecl();
10075 if (NamespaceAliasDecl *AD = dyn_cast<NamespaceAliasDecl>(PrevDecl)) {
10076 // We already have an alias with the same name that points to the same
10077 // namespace; check that it matches.
10078 if (AD->getNamespace()->Equals(getNamespaceDecl(ND))) {
10080 } else if (isVisible(PrevDecl)) {
10081 Diag(AliasLoc, diag::err_redefinition_different_namespace_alias)
10083 Diag(AD->getLocation(), diag::note_previous_namespace_alias)
10084 << AD->getNamespace();
10087 } else if (isVisible(PrevDecl)) {
10088 unsigned DiagID = isa<NamespaceDecl>(PrevDecl->getUnderlyingDecl())
10089 ? diag::err_redefinition
10090 : diag::err_redefinition_different_kind;
10091 Diag(AliasLoc, DiagID) << Alias;
10092 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
10097 // The use of a nested name specifier may trigger deprecation warnings.
10098 DiagnoseUseOfDecl(ND, IdentLoc);
10100 NamespaceAliasDecl *AliasDecl =
10101 NamespaceAliasDecl::Create(Context, CurContext, NamespaceLoc, AliasLoc,
10102 Alias, SS.getWithLocInContext(Context),
10105 AliasDecl->setPreviousDecl(Prev);
10107 PushOnScopeChains(AliasDecl, S);
10112 struct SpecialMemberExceptionSpecInfo
10113 : SpecialMemberVisitor<SpecialMemberExceptionSpecInfo> {
10114 SourceLocation Loc;
10115 Sema::ImplicitExceptionSpecification ExceptSpec;
10117 SpecialMemberExceptionSpecInfo(Sema &S, CXXMethodDecl *MD,
10118 Sema::CXXSpecialMember CSM,
10119 Sema::InheritedConstructorInfo *ICI,
10120 SourceLocation Loc)
10121 : SpecialMemberVisitor(S, MD, CSM, ICI), Loc(Loc), ExceptSpec(S) {}
10123 bool visitBase(CXXBaseSpecifier *Base);
10124 bool visitField(FieldDecl *FD);
10126 void visitClassSubobject(CXXRecordDecl *Class, Subobject Subobj,
10129 void visitSubobjectCall(Subobject Subobj,
10130 Sema::SpecialMemberOverloadResult SMOR);
10134 bool SpecialMemberExceptionSpecInfo::visitBase(CXXBaseSpecifier *Base) {
10135 auto *RT = Base->getType()->getAs<RecordType>();
10139 auto *BaseClass = cast<CXXRecordDecl>(RT->getDecl());
10140 Sema::SpecialMemberOverloadResult SMOR = lookupInheritedCtor(BaseClass);
10141 if (auto *BaseCtor = SMOR.getMethod()) {
10142 visitSubobjectCall(Base, BaseCtor);
10146 visitClassSubobject(BaseClass, Base, 0);
10150 bool SpecialMemberExceptionSpecInfo::visitField(FieldDecl *FD) {
10151 if (CSM == Sema::CXXDefaultConstructor && FD->hasInClassInitializer()) {
10152 Expr *E = FD->getInClassInitializer();
10154 // FIXME: It's a little wasteful to build and throw away a
10155 // CXXDefaultInitExpr here.
10156 // FIXME: We should have a single context note pointing at Loc, and
10157 // this location should be MD->getLocation() instead, since that's
10158 // the location where we actually use the default init expression.
10159 E = S.BuildCXXDefaultInitExpr(Loc, FD).get();
10161 ExceptSpec.CalledExpr(E);
10162 } else if (auto *RT = S.Context.getBaseElementType(FD->getType())
10163 ->getAs<RecordType>()) {
10164 visitClassSubobject(cast<CXXRecordDecl>(RT->getDecl()), FD,
10165 FD->getType().getCVRQualifiers());
10170 void SpecialMemberExceptionSpecInfo::visitClassSubobject(CXXRecordDecl *Class,
10173 FieldDecl *Field = Subobj.dyn_cast<FieldDecl*>();
10174 bool IsMutable = Field && Field->isMutable();
10175 visitSubobjectCall(Subobj, lookupIn(Class, Quals, IsMutable));
10178 void SpecialMemberExceptionSpecInfo::visitSubobjectCall(
10179 Subobject Subobj, Sema::SpecialMemberOverloadResult SMOR) {
10180 // Note, if lookup fails, it doesn't matter what exception specification we
10181 // choose because the special member will be deleted.
10182 if (CXXMethodDecl *MD = SMOR.getMethod())
10183 ExceptSpec.CalledDecl(getSubobjectLoc(Subobj), MD);
10186 static Sema::ImplicitExceptionSpecification
10187 ComputeDefaultedSpecialMemberExceptionSpec(
10188 Sema &S, SourceLocation Loc, CXXMethodDecl *MD, Sema::CXXSpecialMember CSM,
10189 Sema::InheritedConstructorInfo *ICI) {
10190 CXXRecordDecl *ClassDecl = MD->getParent();
10192 // C++ [except.spec]p14:
10193 // An implicitly declared special member function (Clause 12) shall have an
10194 // exception-specification. [...]
10195 SpecialMemberExceptionSpecInfo Info(S, MD, CSM, ICI, Loc);
10196 if (ClassDecl->isInvalidDecl())
10197 return Info.ExceptSpec;
10199 // C++1z [except.spec]p7:
10200 // [Look for exceptions thrown by] a constructor selected [...] to
10201 // initialize a potentially constructed subobject,
10202 // C++1z [except.spec]p8:
10203 // The exception specification for an implicitly-declared destructor, or a
10204 // destructor without a noexcept-specifier, is potentially-throwing if and
10205 // only if any of the destructors for any of its potentially constructed
10206 // subojects is potentially throwing.
10207 // FIXME: We respect the first rule but ignore the "potentially constructed"
10208 // in the second rule to resolve a core issue (no number yet) that would have
10210 // struct A { virtual void f() = 0; virtual ~A() noexcept(false) = 0; };
10211 // struct B : A {};
10212 // struct C : B { void f(); };
10213 // ... due to giving B::~B() a non-throwing exception specification.
10214 Info.visit(Info.IsConstructor ? Info.VisitPotentiallyConstructedBases
10215 : Info.VisitAllBases);
10217 return Info.ExceptSpec;
10221 /// RAII object to register a special member as being currently declared.
10222 struct DeclaringSpecialMember {
10224 Sema::SpecialMemberDecl D;
10225 Sema::ContextRAII SavedContext;
10226 bool WasAlreadyBeingDeclared;
10228 DeclaringSpecialMember(Sema &S, CXXRecordDecl *RD, Sema::CXXSpecialMember CSM)
10229 : S(S), D(RD, CSM), SavedContext(S, RD) {
10230 WasAlreadyBeingDeclared = !S.SpecialMembersBeingDeclared.insert(D).second;
10231 if (WasAlreadyBeingDeclared)
10232 // This almost never happens, but if it does, ensure that our cache
10233 // doesn't contain a stale result.
10234 S.SpecialMemberCache.clear();
10236 // Register a note to be produced if we encounter an error while
10237 // declaring the special member.
10238 Sema::CodeSynthesisContext Ctx;
10239 Ctx.Kind = Sema::CodeSynthesisContext::DeclaringSpecialMember;
10240 // FIXME: We don't have a location to use here. Using the class's
10241 // location maintains the fiction that we declare all special members
10242 // with the class, but (1) it's not clear that lying about that helps our
10243 // users understand what's going on, and (2) there may be outer contexts
10244 // on the stack (some of which are relevant) and printing them exposes
10246 Ctx.PointOfInstantiation = RD->getLocation();
10248 Ctx.SpecialMember = CSM;
10249 S.pushCodeSynthesisContext(Ctx);
10252 ~DeclaringSpecialMember() {
10253 if (!WasAlreadyBeingDeclared) {
10254 S.SpecialMembersBeingDeclared.erase(D);
10255 S.popCodeSynthesisContext();
10259 /// \brief Are we already trying to declare this special member?
10260 bool isAlreadyBeingDeclared() const {
10261 return WasAlreadyBeingDeclared;
10266 void Sema::CheckImplicitSpecialMemberDeclaration(Scope *S, FunctionDecl *FD) {
10267 // Look up any existing declarations, but don't trigger declaration of all
10268 // implicit special members with this name.
10269 DeclarationName Name = FD->getDeclName();
10270 LookupResult R(*this, Name, SourceLocation(), LookupOrdinaryName,
10272 for (auto *D : FD->getParent()->lookup(Name))
10273 if (auto *Acceptable = R.getAcceptableDecl(D))
10274 R.addDecl(Acceptable);
10276 R.suppressDiagnostics();
10278 CheckFunctionDeclaration(S, FD, R, /*IsMemberSpecialization*/false);
10281 CXXConstructorDecl *Sema::DeclareImplicitDefaultConstructor(
10282 CXXRecordDecl *ClassDecl) {
10283 // C++ [class.ctor]p5:
10284 // A default constructor for a class X is a constructor of class X
10285 // that can be called without an argument. If there is no
10286 // user-declared constructor for class X, a default constructor is
10287 // implicitly declared. An implicitly-declared default constructor
10288 // is an inline public member of its class.
10289 assert(ClassDecl->needsImplicitDefaultConstructor() &&
10290 "Should not build implicit default constructor!");
10292 DeclaringSpecialMember DSM(*this, ClassDecl, CXXDefaultConstructor);
10293 if (DSM.isAlreadyBeingDeclared())
10296 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
10297 CXXDefaultConstructor,
10300 // Create the actual constructor declaration.
10301 CanQualType ClassType
10302 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
10303 SourceLocation ClassLoc = ClassDecl->getLocation();
10304 DeclarationName Name
10305 = Context.DeclarationNames.getCXXConstructorName(ClassType);
10306 DeclarationNameInfo NameInfo(Name, ClassLoc);
10307 CXXConstructorDecl *DefaultCon = CXXConstructorDecl::Create(
10308 Context, ClassDecl, ClassLoc, NameInfo, /*Type*/QualType(),
10309 /*TInfo=*/nullptr, /*isExplicit=*/false, /*isInline=*/true,
10310 /*isImplicitlyDeclared=*/true, Constexpr);
10311 DefaultCon->setAccess(AS_public);
10312 DefaultCon->setDefaulted();
10314 if (getLangOpts().CUDA) {
10315 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXDefaultConstructor,
10317 /* ConstRHS */ false,
10318 /* Diagnose */ false);
10321 // Build an exception specification pointing back at this constructor.
10322 FunctionProtoType::ExtProtoInfo EPI = getImplicitMethodEPI(*this, DefaultCon);
10323 DefaultCon->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
10325 // We don't need to use SpecialMemberIsTrivial here; triviality for default
10326 // constructors is easy to compute.
10327 DefaultCon->setTrivial(ClassDecl->hasTrivialDefaultConstructor());
10329 // Note that we have declared this constructor.
10330 ++ASTContext::NumImplicitDefaultConstructorsDeclared;
10332 Scope *S = getScopeForContext(ClassDecl);
10333 CheckImplicitSpecialMemberDeclaration(S, DefaultCon);
10335 if (ShouldDeleteSpecialMember(DefaultCon, CXXDefaultConstructor))
10336 SetDeclDeleted(DefaultCon, ClassLoc);
10339 PushOnScopeChains(DefaultCon, S, false);
10340 ClassDecl->addDecl(DefaultCon);
10345 void Sema::DefineImplicitDefaultConstructor(SourceLocation CurrentLocation,
10346 CXXConstructorDecl *Constructor) {
10347 assert((Constructor->isDefaulted() && Constructor->isDefaultConstructor() &&
10348 !Constructor->doesThisDeclarationHaveABody() &&
10349 !Constructor->isDeleted()) &&
10350 "DefineImplicitDefaultConstructor - call it for implicit default ctor");
10351 if (Constructor->willHaveBody() || Constructor->isInvalidDecl())
10354 CXXRecordDecl *ClassDecl = Constructor->getParent();
10355 assert(ClassDecl && "DefineImplicitDefaultConstructor - invalid constructor");
10357 SynthesizedFunctionScope Scope(*this, Constructor);
10359 // The exception specification is needed because we are defining the
10361 ResolveExceptionSpec(CurrentLocation,
10362 Constructor->getType()->castAs<FunctionProtoType>());
10363 MarkVTableUsed(CurrentLocation, ClassDecl);
10365 // Add a context note for diagnostics produced after this point.
10366 Scope.addContextNote(CurrentLocation);
10368 if (SetCtorInitializers(Constructor, /*AnyErrors=*/false)) {
10369 Constructor->setInvalidDecl();
10373 SourceLocation Loc = Constructor->getLocEnd().isValid()
10374 ? Constructor->getLocEnd()
10375 : Constructor->getLocation();
10376 Constructor->setBody(new (Context) CompoundStmt(Loc));
10377 Constructor->markUsed(Context);
10379 if (ASTMutationListener *L = getASTMutationListener()) {
10380 L->CompletedImplicitDefinition(Constructor);
10383 DiagnoseUninitializedFields(*this, Constructor);
10386 void Sema::ActOnFinishDelayedMemberInitializers(Decl *D) {
10387 // Perform any delayed checks on exception specifications.
10388 CheckDelayedMemberExceptionSpecs();
10391 /// Find or create the fake constructor we synthesize to model constructing an
10392 /// object of a derived class via a constructor of a base class.
10393 CXXConstructorDecl *
10394 Sema::findInheritingConstructor(SourceLocation Loc,
10395 CXXConstructorDecl *BaseCtor,
10396 ConstructorUsingShadowDecl *Shadow) {
10397 CXXRecordDecl *Derived = Shadow->getParent();
10398 SourceLocation UsingLoc = Shadow->getLocation();
10400 // FIXME: Add a new kind of DeclarationName for an inherited constructor.
10401 // For now we use the name of the base class constructor as a member of the
10402 // derived class to indicate a (fake) inherited constructor name.
10403 DeclarationName Name = BaseCtor->getDeclName();
10405 // Check to see if we already have a fake constructor for this inherited
10406 // constructor call.
10407 for (NamedDecl *Ctor : Derived->lookup(Name))
10408 if (declaresSameEntity(cast<CXXConstructorDecl>(Ctor)
10409 ->getInheritedConstructor()
10412 return cast<CXXConstructorDecl>(Ctor);
10414 DeclarationNameInfo NameInfo(Name, UsingLoc);
10415 TypeSourceInfo *TInfo =
10416 Context.getTrivialTypeSourceInfo(BaseCtor->getType(), UsingLoc);
10417 FunctionProtoTypeLoc ProtoLoc =
10418 TInfo->getTypeLoc().IgnoreParens().castAs<FunctionProtoTypeLoc>();
10420 // Check the inherited constructor is valid and find the list of base classes
10421 // from which it was inherited.
10422 InheritedConstructorInfo ICI(*this, Loc, Shadow);
10425 BaseCtor->isConstexpr() &&
10426 defaultedSpecialMemberIsConstexpr(*this, Derived, CXXDefaultConstructor,
10427 false, BaseCtor, &ICI);
10429 CXXConstructorDecl *DerivedCtor = CXXConstructorDecl::Create(
10430 Context, Derived, UsingLoc, NameInfo, TInfo->getType(), TInfo,
10431 BaseCtor->isExplicit(), /*Inline=*/true,
10432 /*ImplicitlyDeclared=*/true, Constexpr,
10433 InheritedConstructor(Shadow, BaseCtor));
10434 if (Shadow->isInvalidDecl())
10435 DerivedCtor->setInvalidDecl();
10437 // Build an unevaluated exception specification for this fake constructor.
10438 const FunctionProtoType *FPT = TInfo->getType()->castAs<FunctionProtoType>();
10439 FunctionProtoType::ExtProtoInfo EPI = FPT->getExtProtoInfo();
10440 EPI.ExceptionSpec.Type = EST_Unevaluated;
10441 EPI.ExceptionSpec.SourceDecl = DerivedCtor;
10442 DerivedCtor->setType(Context.getFunctionType(FPT->getReturnType(),
10443 FPT->getParamTypes(), EPI));
10445 // Build the parameter declarations.
10446 SmallVector<ParmVarDecl *, 16> ParamDecls;
10447 for (unsigned I = 0, N = FPT->getNumParams(); I != N; ++I) {
10448 TypeSourceInfo *TInfo =
10449 Context.getTrivialTypeSourceInfo(FPT->getParamType(I), UsingLoc);
10450 ParmVarDecl *PD = ParmVarDecl::Create(
10451 Context, DerivedCtor, UsingLoc, UsingLoc, /*IdentifierInfo=*/nullptr,
10452 FPT->getParamType(I), TInfo, SC_None, /*DefaultArg=*/nullptr);
10453 PD->setScopeInfo(0, I);
10455 // Ensure attributes are propagated onto parameters (this matters for
10456 // format, pass_object_size, ...).
10457 mergeDeclAttributes(PD, BaseCtor->getParamDecl(I));
10458 ParamDecls.push_back(PD);
10459 ProtoLoc.setParam(I, PD);
10462 // Set up the new constructor.
10463 assert(!BaseCtor->isDeleted() && "should not use deleted constructor");
10464 DerivedCtor->setAccess(BaseCtor->getAccess());
10465 DerivedCtor->setParams(ParamDecls);
10466 Derived->addDecl(DerivedCtor);
10468 if (ShouldDeleteSpecialMember(DerivedCtor, CXXDefaultConstructor, &ICI))
10469 SetDeclDeleted(DerivedCtor, UsingLoc);
10471 return DerivedCtor;
10474 void Sema::NoteDeletedInheritingConstructor(CXXConstructorDecl *Ctor) {
10475 InheritedConstructorInfo ICI(*this, Ctor->getLocation(),
10476 Ctor->getInheritedConstructor().getShadowDecl());
10477 ShouldDeleteSpecialMember(Ctor, CXXDefaultConstructor, &ICI,
10481 void Sema::DefineInheritingConstructor(SourceLocation CurrentLocation,
10482 CXXConstructorDecl *Constructor) {
10483 CXXRecordDecl *ClassDecl = Constructor->getParent();
10484 assert(Constructor->getInheritedConstructor() &&
10485 !Constructor->doesThisDeclarationHaveABody() &&
10486 !Constructor->isDeleted());
10487 if (Constructor->willHaveBody() || Constructor->isInvalidDecl())
10490 // Initializations are performed "as if by a defaulted default constructor",
10491 // so enter the appropriate scope.
10492 SynthesizedFunctionScope Scope(*this, Constructor);
10494 // The exception specification is needed because we are defining the
10496 ResolveExceptionSpec(CurrentLocation,
10497 Constructor->getType()->castAs<FunctionProtoType>());
10498 MarkVTableUsed(CurrentLocation, ClassDecl);
10500 // Add a context note for diagnostics produced after this point.
10501 Scope.addContextNote(CurrentLocation);
10503 ConstructorUsingShadowDecl *Shadow =
10504 Constructor->getInheritedConstructor().getShadowDecl();
10505 CXXConstructorDecl *InheritedCtor =
10506 Constructor->getInheritedConstructor().getConstructor();
10508 // [class.inhctor.init]p1:
10509 // initialization proceeds as if a defaulted default constructor is used to
10510 // initialize the D object and each base class subobject from which the
10511 // constructor was inherited
10513 InheritedConstructorInfo ICI(*this, CurrentLocation, Shadow);
10514 CXXRecordDecl *RD = Shadow->getParent();
10515 SourceLocation InitLoc = Shadow->getLocation();
10517 // Build explicit initializers for all base classes from which the
10518 // constructor was inherited.
10519 SmallVector<CXXCtorInitializer*, 8> Inits;
10520 for (bool VBase : {false, true}) {
10521 for (CXXBaseSpecifier &B : VBase ? RD->vbases() : RD->bases()) {
10522 if (B.isVirtual() != VBase)
10525 auto *BaseRD = B.getType()->getAsCXXRecordDecl();
10529 auto BaseCtor = ICI.findConstructorForBase(BaseRD, InheritedCtor);
10530 if (!BaseCtor.first)
10533 MarkFunctionReferenced(CurrentLocation, BaseCtor.first);
10534 ExprResult Init = new (Context) CXXInheritedCtorInitExpr(
10535 InitLoc, B.getType(), BaseCtor.first, VBase, BaseCtor.second);
10537 auto *TInfo = Context.getTrivialTypeSourceInfo(B.getType(), InitLoc);
10538 Inits.push_back(new (Context) CXXCtorInitializer(
10539 Context, TInfo, VBase, InitLoc, Init.get(), InitLoc,
10540 SourceLocation()));
10544 // We now proceed as if for a defaulted default constructor, with the relevant
10545 // initializers replaced.
10547 if (SetCtorInitializers(Constructor, /*AnyErrors*/false, Inits)) {
10548 Constructor->setInvalidDecl();
10552 Constructor->setBody(new (Context) CompoundStmt(InitLoc));
10553 Constructor->markUsed(Context);
10555 if (ASTMutationListener *L = getASTMutationListener()) {
10556 L->CompletedImplicitDefinition(Constructor);
10559 DiagnoseUninitializedFields(*this, Constructor);
10562 CXXDestructorDecl *Sema::DeclareImplicitDestructor(CXXRecordDecl *ClassDecl) {
10563 // C++ [class.dtor]p2:
10564 // If a class has no user-declared destructor, a destructor is
10565 // declared implicitly. An implicitly-declared destructor is an
10566 // inline public member of its class.
10567 assert(ClassDecl->needsImplicitDestructor());
10569 DeclaringSpecialMember DSM(*this, ClassDecl, CXXDestructor);
10570 if (DSM.isAlreadyBeingDeclared())
10573 // Create the actual destructor declaration.
10574 CanQualType ClassType
10575 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl));
10576 SourceLocation ClassLoc = ClassDecl->getLocation();
10577 DeclarationName Name
10578 = Context.DeclarationNames.getCXXDestructorName(ClassType);
10579 DeclarationNameInfo NameInfo(Name, ClassLoc);
10580 CXXDestructorDecl *Destructor
10581 = CXXDestructorDecl::Create(Context, ClassDecl, ClassLoc, NameInfo,
10582 QualType(), nullptr, /*isInline=*/true,
10583 /*isImplicitlyDeclared=*/true);
10584 Destructor->setAccess(AS_public);
10585 Destructor->setDefaulted();
10587 if (getLangOpts().CUDA) {
10588 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXDestructor,
10590 /* ConstRHS */ false,
10591 /* Diagnose */ false);
10594 // Build an exception specification pointing back at this destructor.
10595 FunctionProtoType::ExtProtoInfo EPI = getImplicitMethodEPI(*this, Destructor);
10596 Destructor->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
10598 // We don't need to use SpecialMemberIsTrivial here; triviality for
10599 // destructors is easy to compute.
10600 Destructor->setTrivial(ClassDecl->hasTrivialDestructor());
10602 // Note that we have declared this destructor.
10603 ++ASTContext::NumImplicitDestructorsDeclared;
10605 Scope *S = getScopeForContext(ClassDecl);
10606 CheckImplicitSpecialMemberDeclaration(S, Destructor);
10608 // We can't check whether an implicit destructor is deleted before we complete
10609 // the definition of the class, because its validity depends on the alignment
10610 // of the class. We'll check this from ActOnFields once the class is complete.
10611 if (ClassDecl->isCompleteDefinition() &&
10612 ShouldDeleteSpecialMember(Destructor, CXXDestructor))
10613 SetDeclDeleted(Destructor, ClassLoc);
10615 // Introduce this destructor into its scope.
10617 PushOnScopeChains(Destructor, S, false);
10618 ClassDecl->addDecl(Destructor);
10623 void Sema::DefineImplicitDestructor(SourceLocation CurrentLocation,
10624 CXXDestructorDecl *Destructor) {
10625 assert((Destructor->isDefaulted() &&
10626 !Destructor->doesThisDeclarationHaveABody() &&
10627 !Destructor->isDeleted()) &&
10628 "DefineImplicitDestructor - call it for implicit default dtor");
10629 if (Destructor->willHaveBody() || Destructor->isInvalidDecl())
10632 CXXRecordDecl *ClassDecl = Destructor->getParent();
10633 assert(ClassDecl && "DefineImplicitDestructor - invalid destructor");
10635 SynthesizedFunctionScope Scope(*this, Destructor);
10637 // The exception specification is needed because we are defining the
10639 ResolveExceptionSpec(CurrentLocation,
10640 Destructor->getType()->castAs<FunctionProtoType>());
10641 MarkVTableUsed(CurrentLocation, ClassDecl);
10643 // Add a context note for diagnostics produced after this point.
10644 Scope.addContextNote(CurrentLocation);
10646 MarkBaseAndMemberDestructorsReferenced(Destructor->getLocation(),
10647 Destructor->getParent());
10649 if (CheckDestructor(Destructor)) {
10650 Destructor->setInvalidDecl();
10654 SourceLocation Loc = Destructor->getLocEnd().isValid()
10655 ? Destructor->getLocEnd()
10656 : Destructor->getLocation();
10657 Destructor->setBody(new (Context) CompoundStmt(Loc));
10658 Destructor->markUsed(Context);
10660 if (ASTMutationListener *L = getASTMutationListener()) {
10661 L->CompletedImplicitDefinition(Destructor);
10665 /// \brief Perform any semantic analysis which needs to be delayed until all
10666 /// pending class member declarations have been parsed.
10667 void Sema::ActOnFinishCXXMemberDecls() {
10668 // If the context is an invalid C++ class, just suppress these checks.
10669 if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(CurContext)) {
10670 if (Record->isInvalidDecl()) {
10671 DelayedDefaultedMemberExceptionSpecs.clear();
10672 DelayedExceptionSpecChecks.clear();
10675 checkForMultipleExportedDefaultConstructors(*this, Record);
10679 void Sema::ActOnFinishCXXNonNestedClass(Decl *D) {
10680 referenceDLLExportedClassMethods();
10683 void Sema::referenceDLLExportedClassMethods() {
10684 if (!DelayedDllExportClasses.empty()) {
10685 // Calling ReferenceDllExportedMethods might cause the current function to
10686 // be called again, so use a local copy of DelayedDllExportClasses.
10687 SmallVector<CXXRecordDecl *, 4> WorkList;
10688 std::swap(DelayedDllExportClasses, WorkList);
10689 for (CXXRecordDecl *Class : WorkList)
10690 ReferenceDllExportedMethods(*this, Class);
10694 void Sema::AdjustDestructorExceptionSpec(CXXRecordDecl *ClassDecl,
10695 CXXDestructorDecl *Destructor) {
10696 assert(getLangOpts().CPlusPlus11 &&
10697 "adjusting dtor exception specs was introduced in c++11");
10699 // C++11 [class.dtor]p3:
10700 // A declaration of a destructor that does not have an exception-
10701 // specification is implicitly considered to have the same exception-
10702 // specification as an implicit declaration.
10703 const FunctionProtoType *DtorType = Destructor->getType()->
10704 getAs<FunctionProtoType>();
10705 if (DtorType->hasExceptionSpec())
10708 // Replace the destructor's type, building off the existing one. Fortunately,
10709 // the only thing of interest in the destructor type is its extended info.
10710 // The return and arguments are fixed.
10711 FunctionProtoType::ExtProtoInfo EPI = DtorType->getExtProtoInfo();
10712 EPI.ExceptionSpec.Type = EST_Unevaluated;
10713 EPI.ExceptionSpec.SourceDecl = Destructor;
10714 Destructor->setType(Context.getFunctionType(Context.VoidTy, None, EPI));
10716 // FIXME: If the destructor has a body that could throw, and the newly created
10717 // spec doesn't allow exceptions, we should emit a warning, because this
10718 // change in behavior can break conforming C++03 programs at runtime.
10719 // However, we don't have a body or an exception specification yet, so it
10720 // needs to be done somewhere else.
10724 /// \brief An abstract base class for all helper classes used in building the
10725 // copy/move operators. These classes serve as factory functions and help us
10726 // avoid using the same Expr* in the AST twice.
10727 class ExprBuilder {
10728 ExprBuilder(const ExprBuilder&) = delete;
10729 ExprBuilder &operator=(const ExprBuilder&) = delete;
10732 static Expr *assertNotNull(Expr *E) {
10733 assert(E && "Expression construction must not fail.");
10739 virtual ~ExprBuilder() {}
10741 virtual Expr *build(Sema &S, SourceLocation Loc) const = 0;
10744 class RefBuilder: public ExprBuilder {
10749 Expr *build(Sema &S, SourceLocation Loc) const override {
10750 return assertNotNull(S.BuildDeclRefExpr(Var, VarType, VK_LValue, Loc).get());
10753 RefBuilder(VarDecl *Var, QualType VarType)
10754 : Var(Var), VarType(VarType) {}
10757 class ThisBuilder: public ExprBuilder {
10759 Expr *build(Sema &S, SourceLocation Loc) const override {
10760 return assertNotNull(S.ActOnCXXThis(Loc).getAs<Expr>());
10764 class CastBuilder: public ExprBuilder {
10765 const ExprBuilder &Builder;
10767 ExprValueKind Kind;
10768 const CXXCastPath &Path;
10771 Expr *build(Sema &S, SourceLocation Loc) const override {
10772 return assertNotNull(S.ImpCastExprToType(Builder.build(S, Loc), Type,
10773 CK_UncheckedDerivedToBase, Kind,
10777 CastBuilder(const ExprBuilder &Builder, QualType Type, ExprValueKind Kind,
10778 const CXXCastPath &Path)
10779 : Builder(Builder), Type(Type), Kind(Kind), Path(Path) {}
10782 class DerefBuilder: public ExprBuilder {
10783 const ExprBuilder &Builder;
10786 Expr *build(Sema &S, SourceLocation Loc) const override {
10787 return assertNotNull(
10788 S.CreateBuiltinUnaryOp(Loc, UO_Deref, Builder.build(S, Loc)).get());
10791 DerefBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
10794 class MemberBuilder: public ExprBuilder {
10795 const ExprBuilder &Builder;
10799 LookupResult &MemberLookup;
10802 Expr *build(Sema &S, SourceLocation Loc) const override {
10803 return assertNotNull(S.BuildMemberReferenceExpr(
10804 Builder.build(S, Loc), Type, Loc, IsArrow, SS, SourceLocation(),
10805 nullptr, MemberLookup, nullptr, nullptr).get());
10808 MemberBuilder(const ExprBuilder &Builder, QualType Type, bool IsArrow,
10809 LookupResult &MemberLookup)
10810 : Builder(Builder), Type(Type), IsArrow(IsArrow),
10811 MemberLookup(MemberLookup) {}
10814 class MoveCastBuilder: public ExprBuilder {
10815 const ExprBuilder &Builder;
10818 Expr *build(Sema &S, SourceLocation Loc) const override {
10819 return assertNotNull(CastForMoving(S, Builder.build(S, Loc)));
10822 MoveCastBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
10825 class LvalueConvBuilder: public ExprBuilder {
10826 const ExprBuilder &Builder;
10829 Expr *build(Sema &S, SourceLocation Loc) const override {
10830 return assertNotNull(
10831 S.DefaultLvalueConversion(Builder.build(S, Loc)).get());
10834 LvalueConvBuilder(const ExprBuilder &Builder) : Builder(Builder) {}
10837 class SubscriptBuilder: public ExprBuilder {
10838 const ExprBuilder &Base;
10839 const ExprBuilder &Index;
10842 Expr *build(Sema &S, SourceLocation Loc) const override {
10843 return assertNotNull(S.CreateBuiltinArraySubscriptExpr(
10844 Base.build(S, Loc), Loc, Index.build(S, Loc), Loc).get());
10847 SubscriptBuilder(const ExprBuilder &Base, const ExprBuilder &Index)
10848 : Base(Base), Index(Index) {}
10851 } // end anonymous namespace
10853 /// When generating a defaulted copy or move assignment operator, if a field
10854 /// should be copied with __builtin_memcpy rather than via explicit assignments,
10855 /// do so. This optimization only applies for arrays of scalars, and for arrays
10856 /// of class type where the selected copy/move-assignment operator is trivial.
10858 buildMemcpyForAssignmentOp(Sema &S, SourceLocation Loc, QualType T,
10859 const ExprBuilder &ToB, const ExprBuilder &FromB) {
10860 // Compute the size of the memory buffer to be copied.
10861 QualType SizeType = S.Context.getSizeType();
10862 llvm::APInt Size(S.Context.getTypeSize(SizeType),
10863 S.Context.getTypeSizeInChars(T).getQuantity());
10865 // Take the address of the field references for "from" and "to". We
10866 // directly construct UnaryOperators here because semantic analysis
10867 // does not permit us to take the address of an xvalue.
10868 Expr *From = FromB.build(S, Loc);
10869 From = new (S.Context) UnaryOperator(From, UO_AddrOf,
10870 S.Context.getPointerType(From->getType()),
10871 VK_RValue, OK_Ordinary, Loc);
10872 Expr *To = ToB.build(S, Loc);
10873 To = new (S.Context) UnaryOperator(To, UO_AddrOf,
10874 S.Context.getPointerType(To->getType()),
10875 VK_RValue, OK_Ordinary, Loc);
10877 const Type *E = T->getBaseElementTypeUnsafe();
10878 bool NeedsCollectableMemCpy =
10879 E->isRecordType() && E->getAs<RecordType>()->getDecl()->hasObjectMember();
10881 // Create a reference to the __builtin_objc_memmove_collectable function
10882 StringRef MemCpyName = NeedsCollectableMemCpy ?
10883 "__builtin_objc_memmove_collectable" :
10884 "__builtin_memcpy";
10885 LookupResult R(S, &S.Context.Idents.get(MemCpyName), Loc,
10886 Sema::LookupOrdinaryName);
10887 S.LookupName(R, S.TUScope, true);
10889 FunctionDecl *MemCpy = R.getAsSingle<FunctionDecl>();
10891 // Something went horribly wrong earlier, and we will have complained
10893 return StmtError();
10895 ExprResult MemCpyRef = S.BuildDeclRefExpr(MemCpy, S.Context.BuiltinFnTy,
10896 VK_RValue, Loc, nullptr);
10897 assert(MemCpyRef.isUsable() && "Builtin reference cannot fail");
10899 Expr *CallArgs[] = {
10900 To, From, IntegerLiteral::Create(S.Context, Size, SizeType, Loc)
10902 ExprResult Call = S.ActOnCallExpr(/*Scope=*/nullptr, MemCpyRef.get(),
10903 Loc, CallArgs, Loc);
10905 assert(!Call.isInvalid() && "Call to __builtin_memcpy cannot fail!");
10906 return Call.getAs<Stmt>();
10909 /// \brief Builds a statement that copies/moves the given entity from \p From to
10912 /// This routine is used to copy/move the members of a class with an
10913 /// implicitly-declared copy/move assignment operator. When the entities being
10914 /// copied are arrays, this routine builds for loops to copy them.
10916 /// \param S The Sema object used for type-checking.
10918 /// \param Loc The location where the implicit copy/move is being generated.
10920 /// \param T The type of the expressions being copied/moved. Both expressions
10921 /// must have this type.
10923 /// \param To The expression we are copying/moving to.
10925 /// \param From The expression we are copying/moving from.
10927 /// \param CopyingBaseSubobject Whether we're copying/moving a base subobject.
10928 /// Otherwise, it's a non-static member subobject.
10930 /// \param Copying Whether we're copying or moving.
10932 /// \param Depth Internal parameter recording the depth of the recursion.
10934 /// \returns A statement or a loop that copies the expressions, or StmtResult(0)
10935 /// if a memcpy should be used instead.
10937 buildSingleCopyAssignRecursively(Sema &S, SourceLocation Loc, QualType T,
10938 const ExprBuilder &To, const ExprBuilder &From,
10939 bool CopyingBaseSubobject, bool Copying,
10940 unsigned Depth = 0) {
10941 // C++11 [class.copy]p28:
10942 // Each subobject is assigned in the manner appropriate to its type:
10944 // - if the subobject is of class type, as if by a call to operator= with
10945 // the subobject as the object expression and the corresponding
10946 // subobject of x as a single function argument (as if by explicit
10947 // qualification; that is, ignoring any possible virtual overriding
10948 // functions in more derived classes);
10950 // C++03 [class.copy]p13:
10951 // - if the subobject is of class type, the copy assignment operator for
10952 // the class is used (as if by explicit qualification; that is,
10953 // ignoring any possible virtual overriding functions in more derived
10955 if (const RecordType *RecordTy = T->getAs<RecordType>()) {
10956 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(RecordTy->getDecl());
10958 // Look for operator=.
10959 DeclarationName Name
10960 = S.Context.DeclarationNames.getCXXOperatorName(OO_Equal);
10961 LookupResult OpLookup(S, Name, Loc, Sema::LookupOrdinaryName);
10962 S.LookupQualifiedName(OpLookup, ClassDecl, false);
10964 // Prior to C++11, filter out any result that isn't a copy/move-assignment
10966 if (!S.getLangOpts().CPlusPlus11) {
10967 LookupResult::Filter F = OpLookup.makeFilter();
10968 while (F.hasNext()) {
10969 NamedDecl *D = F.next();
10970 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D))
10971 if (Method->isCopyAssignmentOperator() ||
10972 (!Copying && Method->isMoveAssignmentOperator()))
10980 // Suppress the protected check (C++ [class.protected]) for each of the
10981 // assignment operators we found. This strange dance is required when
10982 // we're assigning via a base classes's copy-assignment operator. To
10983 // ensure that we're getting the right base class subobject (without
10984 // ambiguities), we need to cast "this" to that subobject type; to
10985 // ensure that we don't go through the virtual call mechanism, we need
10986 // to qualify the operator= name with the base class (see below). However,
10987 // this means that if the base class has a protected copy assignment
10988 // operator, the protected member access check will fail. So, we
10989 // rewrite "protected" access to "public" access in this case, since we
10990 // know by construction that we're calling from a derived class.
10991 if (CopyingBaseSubobject) {
10992 for (LookupResult::iterator L = OpLookup.begin(), LEnd = OpLookup.end();
10994 if (L.getAccess() == AS_protected)
10995 L.setAccess(AS_public);
10999 // Create the nested-name-specifier that will be used to qualify the
11000 // reference to operator=; this is required to suppress the virtual
11003 const Type *CanonicalT = S.Context.getCanonicalType(T.getTypePtr());
11004 SS.MakeTrivial(S.Context,
11005 NestedNameSpecifier::Create(S.Context, nullptr, false,
11009 // Create the reference to operator=.
11010 ExprResult OpEqualRef
11011 = S.BuildMemberReferenceExpr(To.build(S, Loc), T, Loc, /*isArrow=*/false,
11012 SS, /*TemplateKWLoc=*/SourceLocation(),
11013 /*FirstQualifierInScope=*/nullptr,
11015 /*TemplateArgs=*/nullptr, /*S*/nullptr,
11016 /*SuppressQualifierCheck=*/true);
11017 if (OpEqualRef.isInvalid())
11018 return StmtError();
11020 // Build the call to the assignment operator.
11022 Expr *FromInst = From.build(S, Loc);
11023 ExprResult Call = S.BuildCallToMemberFunction(/*Scope=*/nullptr,
11024 OpEqualRef.getAs<Expr>(),
11025 Loc, FromInst, Loc);
11026 if (Call.isInvalid())
11027 return StmtError();
11029 // If we built a call to a trivial 'operator=' while copying an array,
11030 // bail out. We'll replace the whole shebang with a memcpy.
11031 CXXMemberCallExpr *CE = dyn_cast<CXXMemberCallExpr>(Call.get());
11032 if (CE && CE->getMethodDecl()->isTrivial() && Depth)
11033 return StmtResult((Stmt*)nullptr);
11035 // Convert to an expression-statement, and clean up any produced
11037 return S.ActOnExprStmt(Call);
11040 // - if the subobject is of scalar type, the built-in assignment
11041 // operator is used.
11042 const ConstantArrayType *ArrayTy = S.Context.getAsConstantArrayType(T);
11044 ExprResult Assignment = S.CreateBuiltinBinOp(
11045 Loc, BO_Assign, To.build(S, Loc), From.build(S, Loc));
11046 if (Assignment.isInvalid())
11047 return StmtError();
11048 return S.ActOnExprStmt(Assignment);
11051 // - if the subobject is an array, each element is assigned, in the
11052 // manner appropriate to the element type;
11054 // Construct a loop over the array bounds, e.g.,
11056 // for (__SIZE_TYPE__ i0 = 0; i0 != array-size; ++i0)
11058 // that will copy each of the array elements.
11059 QualType SizeType = S.Context.getSizeType();
11061 // Create the iteration variable.
11062 IdentifierInfo *IterationVarName = nullptr;
11064 SmallString<8> Str;
11065 llvm::raw_svector_ostream OS(Str);
11066 OS << "__i" << Depth;
11067 IterationVarName = &S.Context.Idents.get(OS.str());
11069 VarDecl *IterationVar = VarDecl::Create(S.Context, S.CurContext, Loc, Loc,
11070 IterationVarName, SizeType,
11071 S.Context.getTrivialTypeSourceInfo(SizeType, Loc),
11074 // Initialize the iteration variable to zero.
11075 llvm::APInt Zero(S.Context.getTypeSize(SizeType), 0);
11076 IterationVar->setInit(IntegerLiteral::Create(S.Context, Zero, SizeType, Loc));
11078 // Creates a reference to the iteration variable.
11079 RefBuilder IterationVarRef(IterationVar, SizeType);
11080 LvalueConvBuilder IterationVarRefRVal(IterationVarRef);
11082 // Create the DeclStmt that holds the iteration variable.
11083 Stmt *InitStmt = new (S.Context) DeclStmt(DeclGroupRef(IterationVar),Loc,Loc);
11085 // Subscript the "from" and "to" expressions with the iteration variable.
11086 SubscriptBuilder FromIndexCopy(From, IterationVarRefRVal);
11087 MoveCastBuilder FromIndexMove(FromIndexCopy);
11088 const ExprBuilder *FromIndex;
11090 FromIndex = &FromIndexCopy;
11092 FromIndex = &FromIndexMove;
11094 SubscriptBuilder ToIndex(To, IterationVarRefRVal);
11096 // Build the copy/move for an individual element of the array.
11098 buildSingleCopyAssignRecursively(S, Loc, ArrayTy->getElementType(),
11099 ToIndex, *FromIndex, CopyingBaseSubobject,
11100 Copying, Depth + 1);
11101 // Bail out if copying fails or if we determined that we should use memcpy.
11102 if (Copy.isInvalid() || !Copy.get())
11105 // Create the comparison against the array bound.
11107 = ArrayTy->getSize().zextOrTrunc(S.Context.getTypeSize(SizeType));
11109 = new (S.Context) BinaryOperator(IterationVarRefRVal.build(S, Loc),
11110 IntegerLiteral::Create(S.Context, Upper, SizeType, Loc),
11111 BO_NE, S.Context.BoolTy,
11112 VK_RValue, OK_Ordinary, Loc, FPOptions());
11114 // Create the pre-increment of the iteration variable.
11116 = new (S.Context) UnaryOperator(IterationVarRef.build(S, Loc), UO_PreInc,
11117 SizeType, VK_LValue, OK_Ordinary, Loc);
11119 // Construct the loop that copies all elements of this array.
11120 return S.ActOnForStmt(
11121 Loc, Loc, InitStmt,
11122 S.ActOnCondition(nullptr, Loc, Comparison, Sema::ConditionKind::Boolean),
11123 S.MakeFullDiscardedValueExpr(Increment), Loc, Copy.get());
11127 buildSingleCopyAssign(Sema &S, SourceLocation Loc, QualType T,
11128 const ExprBuilder &To, const ExprBuilder &From,
11129 bool CopyingBaseSubobject, bool Copying) {
11130 // Maybe we should use a memcpy?
11131 if (T->isArrayType() && !T.isConstQualified() && !T.isVolatileQualified() &&
11132 T.isTriviallyCopyableType(S.Context))
11133 return buildMemcpyForAssignmentOp(S, Loc, T, To, From);
11135 StmtResult Result(buildSingleCopyAssignRecursively(S, Loc, T, To, From,
11136 CopyingBaseSubobject,
11139 // If we ended up picking a trivial assignment operator for an array of a
11140 // non-trivially-copyable class type, just emit a memcpy.
11141 if (!Result.isInvalid() && !Result.get())
11142 return buildMemcpyForAssignmentOp(S, Loc, T, To, From);
11147 CXXMethodDecl *Sema::DeclareImplicitCopyAssignment(CXXRecordDecl *ClassDecl) {
11148 // Note: The following rules are largely analoguous to the copy
11149 // constructor rules. Note that virtual bases are not taken into account
11150 // for determining the argument type of the operator. Note also that
11151 // operators taking an object instead of a reference are allowed.
11152 assert(ClassDecl->needsImplicitCopyAssignment());
11154 DeclaringSpecialMember DSM(*this, ClassDecl, CXXCopyAssignment);
11155 if (DSM.isAlreadyBeingDeclared())
11158 QualType ArgType = Context.getTypeDeclType(ClassDecl);
11159 QualType RetType = Context.getLValueReferenceType(ArgType);
11160 bool Const = ClassDecl->implicitCopyAssignmentHasConstParam();
11162 ArgType = ArgType.withConst();
11163 ArgType = Context.getLValueReferenceType(ArgType);
11165 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
11169 // An implicitly-declared copy assignment operator is an inline public
11170 // member of its class.
11171 DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
11172 SourceLocation ClassLoc = ClassDecl->getLocation();
11173 DeclarationNameInfo NameInfo(Name, ClassLoc);
11174 CXXMethodDecl *CopyAssignment =
11175 CXXMethodDecl::Create(Context, ClassDecl, ClassLoc, NameInfo, QualType(),
11176 /*TInfo=*/nullptr, /*StorageClass=*/SC_None,
11177 /*isInline=*/true, Constexpr, SourceLocation());
11178 CopyAssignment->setAccess(AS_public);
11179 CopyAssignment->setDefaulted();
11180 CopyAssignment->setImplicit();
11182 if (getLangOpts().CUDA) {
11183 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXCopyAssignment,
11185 /* ConstRHS */ Const,
11186 /* Diagnose */ false);
11189 // Build an exception specification pointing back at this member.
11190 FunctionProtoType::ExtProtoInfo EPI =
11191 getImplicitMethodEPI(*this, CopyAssignment);
11192 CopyAssignment->setType(Context.getFunctionType(RetType, ArgType, EPI));
11194 // Add the parameter to the operator.
11195 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyAssignment,
11196 ClassLoc, ClassLoc,
11197 /*Id=*/nullptr, ArgType,
11198 /*TInfo=*/nullptr, SC_None,
11200 CopyAssignment->setParams(FromParam);
11202 CopyAssignment->setTrivial(
11203 ClassDecl->needsOverloadResolutionForCopyAssignment()
11204 ? SpecialMemberIsTrivial(CopyAssignment, CXXCopyAssignment)
11205 : ClassDecl->hasTrivialCopyAssignment());
11207 // Note that we have added this copy-assignment operator.
11208 ++ASTContext::NumImplicitCopyAssignmentOperatorsDeclared;
11210 Scope *S = getScopeForContext(ClassDecl);
11211 CheckImplicitSpecialMemberDeclaration(S, CopyAssignment);
11213 if (ShouldDeleteSpecialMember(CopyAssignment, CXXCopyAssignment))
11214 SetDeclDeleted(CopyAssignment, ClassLoc);
11217 PushOnScopeChains(CopyAssignment, S, false);
11218 ClassDecl->addDecl(CopyAssignment);
11220 return CopyAssignment;
11223 /// Diagnose an implicit copy operation for a class which is odr-used, but
11224 /// which is deprecated because the class has a user-declared copy constructor,
11225 /// copy assignment operator, or destructor.
11226 static void diagnoseDeprecatedCopyOperation(Sema &S, CXXMethodDecl *CopyOp) {
11227 assert(CopyOp->isImplicit());
11229 CXXRecordDecl *RD = CopyOp->getParent();
11230 CXXMethodDecl *UserDeclaredOperation = nullptr;
11232 // In Microsoft mode, assignment operations don't affect constructors and
11234 if (RD->hasUserDeclaredDestructor()) {
11235 UserDeclaredOperation = RD->getDestructor();
11236 } else if (!isa<CXXConstructorDecl>(CopyOp) &&
11237 RD->hasUserDeclaredCopyConstructor() &&
11238 !S.getLangOpts().MSVCCompat) {
11239 // Find any user-declared copy constructor.
11240 for (auto *I : RD->ctors()) {
11241 if (I->isCopyConstructor()) {
11242 UserDeclaredOperation = I;
11246 assert(UserDeclaredOperation);
11247 } else if (isa<CXXConstructorDecl>(CopyOp) &&
11248 RD->hasUserDeclaredCopyAssignment() &&
11249 !S.getLangOpts().MSVCCompat) {
11250 // Find any user-declared move assignment operator.
11251 for (auto *I : RD->methods()) {
11252 if (I->isCopyAssignmentOperator()) {
11253 UserDeclaredOperation = I;
11257 assert(UserDeclaredOperation);
11260 if (UserDeclaredOperation) {
11261 S.Diag(UserDeclaredOperation->getLocation(),
11262 diag::warn_deprecated_copy_operation)
11263 << RD << /*copy assignment*/!isa<CXXConstructorDecl>(CopyOp)
11264 << /*destructor*/isa<CXXDestructorDecl>(UserDeclaredOperation);
11268 void Sema::DefineImplicitCopyAssignment(SourceLocation CurrentLocation,
11269 CXXMethodDecl *CopyAssignOperator) {
11270 assert((CopyAssignOperator->isDefaulted() &&
11271 CopyAssignOperator->isOverloadedOperator() &&
11272 CopyAssignOperator->getOverloadedOperator() == OO_Equal &&
11273 !CopyAssignOperator->doesThisDeclarationHaveABody() &&
11274 !CopyAssignOperator->isDeleted()) &&
11275 "DefineImplicitCopyAssignment called for wrong function");
11276 if (CopyAssignOperator->willHaveBody() || CopyAssignOperator->isInvalidDecl())
11279 CXXRecordDecl *ClassDecl = CopyAssignOperator->getParent();
11280 if (ClassDecl->isInvalidDecl()) {
11281 CopyAssignOperator->setInvalidDecl();
11285 SynthesizedFunctionScope Scope(*this, CopyAssignOperator);
11287 // The exception specification is needed because we are defining the
11289 ResolveExceptionSpec(CurrentLocation,
11290 CopyAssignOperator->getType()->castAs<FunctionProtoType>());
11292 // Add a context note for diagnostics produced after this point.
11293 Scope.addContextNote(CurrentLocation);
11295 // C++11 [class.copy]p18:
11296 // The [definition of an implicitly declared copy assignment operator] is
11297 // deprecated if the class has a user-declared copy constructor or a
11298 // user-declared destructor.
11299 if (getLangOpts().CPlusPlus11 && CopyAssignOperator->isImplicit())
11300 diagnoseDeprecatedCopyOperation(*this, CopyAssignOperator);
11302 // C++0x [class.copy]p30:
11303 // The implicitly-defined or explicitly-defaulted copy assignment operator
11304 // for a non-union class X performs memberwise copy assignment of its
11305 // subobjects. The direct base classes of X are assigned first, in the
11306 // order of their declaration in the base-specifier-list, and then the
11307 // immediate non-static data members of X are assigned, in the order in
11308 // which they were declared in the class definition.
11310 // The statements that form the synthesized function body.
11311 SmallVector<Stmt*, 8> Statements;
11313 // The parameter for the "other" object, which we are copying from.
11314 ParmVarDecl *Other = CopyAssignOperator->getParamDecl(0);
11315 Qualifiers OtherQuals = Other->getType().getQualifiers();
11316 QualType OtherRefType = Other->getType();
11317 if (const LValueReferenceType *OtherRef
11318 = OtherRefType->getAs<LValueReferenceType>()) {
11319 OtherRefType = OtherRef->getPointeeType();
11320 OtherQuals = OtherRefType.getQualifiers();
11323 // Our location for everything implicitly-generated.
11324 SourceLocation Loc = CopyAssignOperator->getLocEnd().isValid()
11325 ? CopyAssignOperator->getLocEnd()
11326 : CopyAssignOperator->getLocation();
11328 // Builds a DeclRefExpr for the "other" object.
11329 RefBuilder OtherRef(Other, OtherRefType);
11331 // Builds the "this" pointer.
11334 // Assign base classes.
11335 bool Invalid = false;
11336 for (auto &Base : ClassDecl->bases()) {
11337 // Form the assignment:
11338 // static_cast<Base*>(this)->Base::operator=(static_cast<Base&>(other));
11339 QualType BaseType = Base.getType().getUnqualifiedType();
11340 if (!BaseType->isRecordType()) {
11345 CXXCastPath BasePath;
11346 BasePath.push_back(&Base);
11348 // Construct the "from" expression, which is an implicit cast to the
11349 // appropriately-qualified base type.
11350 CastBuilder From(OtherRef, Context.getQualifiedType(BaseType, OtherQuals),
11351 VK_LValue, BasePath);
11353 // Dereference "this".
11354 DerefBuilder DerefThis(This);
11355 CastBuilder To(DerefThis,
11356 Context.getCVRQualifiedType(
11357 BaseType, CopyAssignOperator->getTypeQualifiers()),
11358 VK_LValue, BasePath);
11361 StmtResult Copy = buildSingleCopyAssign(*this, Loc, BaseType,
11363 /*CopyingBaseSubobject=*/true,
11365 if (Copy.isInvalid()) {
11366 CopyAssignOperator->setInvalidDecl();
11370 // Success! Record the copy.
11371 Statements.push_back(Copy.getAs<Expr>());
11374 // Assign non-static members.
11375 for (auto *Field : ClassDecl->fields()) {
11376 // FIXME: We should form some kind of AST representation for the implied
11377 // memcpy in a union copy operation.
11378 if (Field->isUnnamedBitfield() || Field->getParent()->isUnion())
11381 if (Field->isInvalidDecl()) {
11386 // Check for members of reference type; we can't copy those.
11387 if (Field->getType()->isReferenceType()) {
11388 Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
11389 << Context.getTagDeclType(ClassDecl) << 0 << Field->getDeclName();
11390 Diag(Field->getLocation(), diag::note_declared_at);
11395 // Check for members of const-qualified, non-class type.
11396 QualType BaseType = Context.getBaseElementType(Field->getType());
11397 if (!BaseType->getAs<RecordType>() && BaseType.isConstQualified()) {
11398 Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
11399 << Context.getTagDeclType(ClassDecl) << 1 << Field->getDeclName();
11400 Diag(Field->getLocation(), diag::note_declared_at);
11405 // Suppress assigning zero-width bitfields.
11406 if (Field->isBitField() && Field->getBitWidthValue(Context) == 0)
11409 QualType FieldType = Field->getType().getNonReferenceType();
11410 if (FieldType->isIncompleteArrayType()) {
11411 assert(ClassDecl->hasFlexibleArrayMember() &&
11412 "Incomplete array type is not valid");
11416 // Build references to the field in the object we're copying from and to.
11417 CXXScopeSpec SS; // Intentionally empty
11418 LookupResult MemberLookup(*this, Field->getDeclName(), Loc,
11420 MemberLookup.addDecl(Field);
11421 MemberLookup.resolveKind();
11423 MemberBuilder From(OtherRef, OtherRefType, /*IsArrow=*/false, MemberLookup);
11425 MemberBuilder To(This, getCurrentThisType(), /*IsArrow=*/true, MemberLookup);
11427 // Build the copy of this field.
11428 StmtResult Copy = buildSingleCopyAssign(*this, Loc, FieldType,
11430 /*CopyingBaseSubobject=*/false,
11432 if (Copy.isInvalid()) {
11433 CopyAssignOperator->setInvalidDecl();
11437 // Success! Record the copy.
11438 Statements.push_back(Copy.getAs<Stmt>());
11442 // Add a "return *this;"
11443 ExprResult ThisObj = CreateBuiltinUnaryOp(Loc, UO_Deref, This.build(*this, Loc));
11445 StmtResult Return = BuildReturnStmt(Loc, ThisObj.get());
11446 if (Return.isInvalid())
11449 Statements.push_back(Return.getAs<Stmt>());
11453 CopyAssignOperator->setInvalidDecl();
11459 CompoundScopeRAII CompoundScope(*this);
11460 Body = ActOnCompoundStmt(Loc, Loc, Statements,
11461 /*isStmtExpr=*/false);
11462 assert(!Body.isInvalid() && "Compound statement creation cannot fail");
11464 CopyAssignOperator->setBody(Body.getAs<Stmt>());
11465 CopyAssignOperator->markUsed(Context);
11467 if (ASTMutationListener *L = getASTMutationListener()) {
11468 L->CompletedImplicitDefinition(CopyAssignOperator);
11472 CXXMethodDecl *Sema::DeclareImplicitMoveAssignment(CXXRecordDecl *ClassDecl) {
11473 assert(ClassDecl->needsImplicitMoveAssignment());
11475 DeclaringSpecialMember DSM(*this, ClassDecl, CXXMoveAssignment);
11476 if (DSM.isAlreadyBeingDeclared())
11479 // Note: The following rules are largely analoguous to the move
11480 // constructor rules.
11482 QualType ArgType = Context.getTypeDeclType(ClassDecl);
11483 QualType RetType = Context.getLValueReferenceType(ArgType);
11484 ArgType = Context.getRValueReferenceType(ArgType);
11486 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
11490 // An implicitly-declared move assignment operator is an inline public
11491 // member of its class.
11492 DeclarationName Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
11493 SourceLocation ClassLoc = ClassDecl->getLocation();
11494 DeclarationNameInfo NameInfo(Name, ClassLoc);
11495 CXXMethodDecl *MoveAssignment =
11496 CXXMethodDecl::Create(Context, ClassDecl, ClassLoc, NameInfo, QualType(),
11497 /*TInfo=*/nullptr, /*StorageClass=*/SC_None,
11498 /*isInline=*/true, Constexpr, SourceLocation());
11499 MoveAssignment->setAccess(AS_public);
11500 MoveAssignment->setDefaulted();
11501 MoveAssignment->setImplicit();
11503 if (getLangOpts().CUDA) {
11504 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXMoveAssignment,
11506 /* ConstRHS */ false,
11507 /* Diagnose */ false);
11510 // Build an exception specification pointing back at this member.
11511 FunctionProtoType::ExtProtoInfo EPI =
11512 getImplicitMethodEPI(*this, MoveAssignment);
11513 MoveAssignment->setType(Context.getFunctionType(RetType, ArgType, EPI));
11515 // Add the parameter to the operator.
11516 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, MoveAssignment,
11517 ClassLoc, ClassLoc,
11518 /*Id=*/nullptr, ArgType,
11519 /*TInfo=*/nullptr, SC_None,
11521 MoveAssignment->setParams(FromParam);
11523 MoveAssignment->setTrivial(
11524 ClassDecl->needsOverloadResolutionForMoveAssignment()
11525 ? SpecialMemberIsTrivial(MoveAssignment, CXXMoveAssignment)
11526 : ClassDecl->hasTrivialMoveAssignment());
11528 // Note that we have added this copy-assignment operator.
11529 ++ASTContext::NumImplicitMoveAssignmentOperatorsDeclared;
11531 Scope *S = getScopeForContext(ClassDecl);
11532 CheckImplicitSpecialMemberDeclaration(S, MoveAssignment);
11534 if (ShouldDeleteSpecialMember(MoveAssignment, CXXMoveAssignment)) {
11535 ClassDecl->setImplicitMoveAssignmentIsDeleted();
11536 SetDeclDeleted(MoveAssignment, ClassLoc);
11540 PushOnScopeChains(MoveAssignment, S, false);
11541 ClassDecl->addDecl(MoveAssignment);
11543 return MoveAssignment;
11546 /// Check if we're implicitly defining a move assignment operator for a class
11547 /// with virtual bases. Such a move assignment might move-assign the virtual
11548 /// base multiple times.
11549 static void checkMoveAssignmentForRepeatedMove(Sema &S, CXXRecordDecl *Class,
11550 SourceLocation CurrentLocation) {
11551 assert(!Class->isDependentContext() && "should not define dependent move");
11553 // Only a virtual base could get implicitly move-assigned multiple times.
11554 // Only a non-trivial move assignment can observe this. We only want to
11555 // diagnose if we implicitly define an assignment operator that assigns
11556 // two base classes, both of which move-assign the same virtual base.
11557 if (Class->getNumVBases() == 0 || Class->hasTrivialMoveAssignment() ||
11558 Class->getNumBases() < 2)
11561 llvm::SmallVector<CXXBaseSpecifier *, 16> Worklist;
11562 typedef llvm::DenseMap<CXXRecordDecl*, CXXBaseSpecifier*> VBaseMap;
11565 for (auto &BI : Class->bases()) {
11566 Worklist.push_back(&BI);
11567 while (!Worklist.empty()) {
11568 CXXBaseSpecifier *BaseSpec = Worklist.pop_back_val();
11569 CXXRecordDecl *Base = BaseSpec->getType()->getAsCXXRecordDecl();
11571 // If the base has no non-trivial move assignment operators,
11572 // we don't care about moves from it.
11573 if (!Base->hasNonTrivialMoveAssignment())
11576 // If there's nothing virtual here, skip it.
11577 if (!BaseSpec->isVirtual() && !Base->getNumVBases())
11580 // If we're not actually going to call a move assignment for this base,
11581 // or the selected move assignment is trivial, skip it.
11582 Sema::SpecialMemberOverloadResult SMOR =
11583 S.LookupSpecialMember(Base, Sema::CXXMoveAssignment,
11584 /*ConstArg*/false, /*VolatileArg*/false,
11585 /*RValueThis*/true, /*ConstThis*/false,
11586 /*VolatileThis*/false);
11587 if (!SMOR.getMethod() || SMOR.getMethod()->isTrivial() ||
11588 !SMOR.getMethod()->isMoveAssignmentOperator())
11591 if (BaseSpec->isVirtual()) {
11592 // We're going to move-assign this virtual base, and its move
11593 // assignment operator is not trivial. If this can happen for
11594 // multiple distinct direct bases of Class, diagnose it. (If it
11595 // only happens in one base, we'll diagnose it when synthesizing
11596 // that base class's move assignment operator.)
11597 CXXBaseSpecifier *&Existing =
11598 VBases.insert(std::make_pair(Base->getCanonicalDecl(), &BI))
11600 if (Existing && Existing != &BI) {
11601 S.Diag(CurrentLocation, diag::warn_vbase_moved_multiple_times)
11603 S.Diag(Existing->getLocStart(), diag::note_vbase_moved_here)
11604 << (Base->getCanonicalDecl() ==
11605 Existing->getType()->getAsCXXRecordDecl()->getCanonicalDecl())
11606 << Base << Existing->getType() << Existing->getSourceRange();
11607 S.Diag(BI.getLocStart(), diag::note_vbase_moved_here)
11608 << (Base->getCanonicalDecl() ==
11609 BI.getType()->getAsCXXRecordDecl()->getCanonicalDecl())
11610 << Base << BI.getType() << BaseSpec->getSourceRange();
11612 // Only diagnose each vbase once.
11613 Existing = nullptr;
11616 // Only walk over bases that have defaulted move assignment operators.
11617 // We assume that any user-provided move assignment operator handles
11618 // the multiple-moves-of-vbase case itself somehow.
11619 if (!SMOR.getMethod()->isDefaulted())
11622 // We're going to move the base classes of Base. Add them to the list.
11623 for (auto &BI : Base->bases())
11624 Worklist.push_back(&BI);
11630 void Sema::DefineImplicitMoveAssignment(SourceLocation CurrentLocation,
11631 CXXMethodDecl *MoveAssignOperator) {
11632 assert((MoveAssignOperator->isDefaulted() &&
11633 MoveAssignOperator->isOverloadedOperator() &&
11634 MoveAssignOperator->getOverloadedOperator() == OO_Equal &&
11635 !MoveAssignOperator->doesThisDeclarationHaveABody() &&
11636 !MoveAssignOperator->isDeleted()) &&
11637 "DefineImplicitMoveAssignment called for wrong function");
11638 if (MoveAssignOperator->willHaveBody() || MoveAssignOperator->isInvalidDecl())
11641 CXXRecordDecl *ClassDecl = MoveAssignOperator->getParent();
11642 if (ClassDecl->isInvalidDecl()) {
11643 MoveAssignOperator->setInvalidDecl();
11647 // C++0x [class.copy]p28:
11648 // The implicitly-defined or move assignment operator for a non-union class
11649 // X performs memberwise move assignment of its subobjects. The direct base
11650 // classes of X are assigned first, in the order of their declaration in the
11651 // base-specifier-list, and then the immediate non-static data members of X
11652 // are assigned, in the order in which they were declared in the class
11655 // Issue a warning if our implicit move assignment operator will move
11656 // from a virtual base more than once.
11657 checkMoveAssignmentForRepeatedMove(*this, ClassDecl, CurrentLocation);
11659 SynthesizedFunctionScope Scope(*this, MoveAssignOperator);
11661 // The exception specification is needed because we are defining the
11663 ResolveExceptionSpec(CurrentLocation,
11664 MoveAssignOperator->getType()->castAs<FunctionProtoType>());
11666 // Add a context note for diagnostics produced after this point.
11667 Scope.addContextNote(CurrentLocation);
11669 // The statements that form the synthesized function body.
11670 SmallVector<Stmt*, 8> Statements;
11672 // The parameter for the "other" object, which we are move from.
11673 ParmVarDecl *Other = MoveAssignOperator->getParamDecl(0);
11674 QualType OtherRefType = Other->getType()->
11675 getAs<RValueReferenceType>()->getPointeeType();
11676 assert(!OtherRefType.getQualifiers() &&
11677 "Bad argument type of defaulted move assignment");
11679 // Our location for everything implicitly-generated.
11680 SourceLocation Loc = MoveAssignOperator->getLocEnd().isValid()
11681 ? MoveAssignOperator->getLocEnd()
11682 : MoveAssignOperator->getLocation();
11684 // Builds a reference to the "other" object.
11685 RefBuilder OtherRef(Other, OtherRefType);
11687 MoveCastBuilder MoveOther(OtherRef);
11689 // Builds the "this" pointer.
11692 // Assign base classes.
11693 bool Invalid = false;
11694 for (auto &Base : ClassDecl->bases()) {
11695 // C++11 [class.copy]p28:
11696 // It is unspecified whether subobjects representing virtual base classes
11697 // are assigned more than once by the implicitly-defined copy assignment
11699 // FIXME: Do not assign to a vbase that will be assigned by some other base
11700 // class. For a move-assignment, this can result in the vbase being moved
11703 // Form the assignment:
11704 // static_cast<Base*>(this)->Base::operator=(static_cast<Base&&>(other));
11705 QualType BaseType = Base.getType().getUnqualifiedType();
11706 if (!BaseType->isRecordType()) {
11711 CXXCastPath BasePath;
11712 BasePath.push_back(&Base);
11714 // Construct the "from" expression, which is an implicit cast to the
11715 // appropriately-qualified base type.
11716 CastBuilder From(OtherRef, BaseType, VK_XValue, BasePath);
11718 // Dereference "this".
11719 DerefBuilder DerefThis(This);
11721 // Implicitly cast "this" to the appropriately-qualified base type.
11722 CastBuilder To(DerefThis,
11723 Context.getCVRQualifiedType(
11724 BaseType, MoveAssignOperator->getTypeQualifiers()),
11725 VK_LValue, BasePath);
11728 StmtResult Move = buildSingleCopyAssign(*this, Loc, BaseType,
11730 /*CopyingBaseSubobject=*/true,
11731 /*Copying=*/false);
11732 if (Move.isInvalid()) {
11733 MoveAssignOperator->setInvalidDecl();
11737 // Success! Record the move.
11738 Statements.push_back(Move.getAs<Expr>());
11741 // Assign non-static members.
11742 for (auto *Field : ClassDecl->fields()) {
11743 // FIXME: We should form some kind of AST representation for the implied
11744 // memcpy in a union copy operation.
11745 if (Field->isUnnamedBitfield() || Field->getParent()->isUnion())
11748 if (Field->isInvalidDecl()) {
11753 // Check for members of reference type; we can't move those.
11754 if (Field->getType()->isReferenceType()) {
11755 Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
11756 << Context.getTagDeclType(ClassDecl) << 0 << Field->getDeclName();
11757 Diag(Field->getLocation(), diag::note_declared_at);
11762 // Check for members of const-qualified, non-class type.
11763 QualType BaseType = Context.getBaseElementType(Field->getType());
11764 if (!BaseType->getAs<RecordType>() && BaseType.isConstQualified()) {
11765 Diag(ClassDecl->getLocation(), diag::err_uninitialized_member_for_assign)
11766 << Context.getTagDeclType(ClassDecl) << 1 << Field->getDeclName();
11767 Diag(Field->getLocation(), diag::note_declared_at);
11772 // Suppress assigning zero-width bitfields.
11773 if (Field->isBitField() && Field->getBitWidthValue(Context) == 0)
11776 QualType FieldType = Field->getType().getNonReferenceType();
11777 if (FieldType->isIncompleteArrayType()) {
11778 assert(ClassDecl->hasFlexibleArrayMember() &&
11779 "Incomplete array type is not valid");
11783 // Build references to the field in the object we're copying from and to.
11784 LookupResult MemberLookup(*this, Field->getDeclName(), Loc,
11786 MemberLookup.addDecl(Field);
11787 MemberLookup.resolveKind();
11788 MemberBuilder From(MoveOther, OtherRefType,
11789 /*IsArrow=*/false, MemberLookup);
11790 MemberBuilder To(This, getCurrentThisType(),
11791 /*IsArrow=*/true, MemberLookup);
11793 assert(!From.build(*this, Loc)->isLValue() && // could be xvalue or prvalue
11794 "Member reference with rvalue base must be rvalue except for reference "
11795 "members, which aren't allowed for move assignment.");
11797 // Build the move of this field.
11798 StmtResult Move = buildSingleCopyAssign(*this, Loc, FieldType,
11800 /*CopyingBaseSubobject=*/false,
11801 /*Copying=*/false);
11802 if (Move.isInvalid()) {
11803 MoveAssignOperator->setInvalidDecl();
11807 // Success! Record the copy.
11808 Statements.push_back(Move.getAs<Stmt>());
11812 // Add a "return *this;"
11813 ExprResult ThisObj =
11814 CreateBuiltinUnaryOp(Loc, UO_Deref, This.build(*this, Loc));
11816 StmtResult Return = BuildReturnStmt(Loc, ThisObj.get());
11817 if (Return.isInvalid())
11820 Statements.push_back(Return.getAs<Stmt>());
11824 MoveAssignOperator->setInvalidDecl();
11830 CompoundScopeRAII CompoundScope(*this);
11831 Body = ActOnCompoundStmt(Loc, Loc, Statements,
11832 /*isStmtExpr=*/false);
11833 assert(!Body.isInvalid() && "Compound statement creation cannot fail");
11835 MoveAssignOperator->setBody(Body.getAs<Stmt>());
11836 MoveAssignOperator->markUsed(Context);
11838 if (ASTMutationListener *L = getASTMutationListener()) {
11839 L->CompletedImplicitDefinition(MoveAssignOperator);
11843 CXXConstructorDecl *Sema::DeclareImplicitCopyConstructor(
11844 CXXRecordDecl *ClassDecl) {
11845 // C++ [class.copy]p4:
11846 // If the class definition does not explicitly declare a copy
11847 // constructor, one is declared implicitly.
11848 assert(ClassDecl->needsImplicitCopyConstructor());
11850 DeclaringSpecialMember DSM(*this, ClassDecl, CXXCopyConstructor);
11851 if (DSM.isAlreadyBeingDeclared())
11854 QualType ClassType = Context.getTypeDeclType(ClassDecl);
11855 QualType ArgType = ClassType;
11856 bool Const = ClassDecl->implicitCopyConstructorHasConstParam();
11858 ArgType = ArgType.withConst();
11859 ArgType = Context.getLValueReferenceType(ArgType);
11861 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
11862 CXXCopyConstructor,
11865 DeclarationName Name
11866 = Context.DeclarationNames.getCXXConstructorName(
11867 Context.getCanonicalType(ClassType));
11868 SourceLocation ClassLoc = ClassDecl->getLocation();
11869 DeclarationNameInfo NameInfo(Name, ClassLoc);
11871 // An implicitly-declared copy constructor is an inline public
11872 // member of its class.
11873 CXXConstructorDecl *CopyConstructor = CXXConstructorDecl::Create(
11874 Context, ClassDecl, ClassLoc, NameInfo, QualType(), /*TInfo=*/nullptr,
11875 /*isExplicit=*/false, /*isInline=*/true, /*isImplicitlyDeclared=*/true,
11877 CopyConstructor->setAccess(AS_public);
11878 CopyConstructor->setDefaulted();
11880 if (getLangOpts().CUDA) {
11881 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXCopyConstructor,
11883 /* ConstRHS */ Const,
11884 /* Diagnose */ false);
11887 // Build an exception specification pointing back at this member.
11888 FunctionProtoType::ExtProtoInfo EPI =
11889 getImplicitMethodEPI(*this, CopyConstructor);
11890 CopyConstructor->setType(
11891 Context.getFunctionType(Context.VoidTy, ArgType, EPI));
11893 // Add the parameter to the constructor.
11894 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor,
11895 ClassLoc, ClassLoc,
11896 /*IdentifierInfo=*/nullptr,
11897 ArgType, /*TInfo=*/nullptr,
11899 CopyConstructor->setParams(FromParam);
11901 CopyConstructor->setTrivial(
11902 ClassDecl->needsOverloadResolutionForCopyConstructor()
11903 ? SpecialMemberIsTrivial(CopyConstructor, CXXCopyConstructor)
11904 : ClassDecl->hasTrivialCopyConstructor());
11906 // Note that we have declared this constructor.
11907 ++ASTContext::NumImplicitCopyConstructorsDeclared;
11909 Scope *S = getScopeForContext(ClassDecl);
11910 CheckImplicitSpecialMemberDeclaration(S, CopyConstructor);
11912 if (ShouldDeleteSpecialMember(CopyConstructor, CXXCopyConstructor))
11913 SetDeclDeleted(CopyConstructor, ClassLoc);
11916 PushOnScopeChains(CopyConstructor, S, false);
11917 ClassDecl->addDecl(CopyConstructor);
11919 return CopyConstructor;
11922 void Sema::DefineImplicitCopyConstructor(SourceLocation CurrentLocation,
11923 CXXConstructorDecl *CopyConstructor) {
11924 assert((CopyConstructor->isDefaulted() &&
11925 CopyConstructor->isCopyConstructor() &&
11926 !CopyConstructor->doesThisDeclarationHaveABody() &&
11927 !CopyConstructor->isDeleted()) &&
11928 "DefineImplicitCopyConstructor - call it for implicit copy ctor");
11929 if (CopyConstructor->willHaveBody() || CopyConstructor->isInvalidDecl())
11932 CXXRecordDecl *ClassDecl = CopyConstructor->getParent();
11933 assert(ClassDecl && "DefineImplicitCopyConstructor - invalid constructor");
11935 SynthesizedFunctionScope Scope(*this, CopyConstructor);
11937 // The exception specification is needed because we are defining the
11939 ResolveExceptionSpec(CurrentLocation,
11940 CopyConstructor->getType()->castAs<FunctionProtoType>());
11941 MarkVTableUsed(CurrentLocation, ClassDecl);
11943 // Add a context note for diagnostics produced after this point.
11944 Scope.addContextNote(CurrentLocation);
11946 // C++11 [class.copy]p7:
11947 // The [definition of an implicitly declared copy constructor] is
11948 // deprecated if the class has a user-declared copy assignment operator
11949 // or a user-declared destructor.
11950 if (getLangOpts().CPlusPlus11 && CopyConstructor->isImplicit())
11951 diagnoseDeprecatedCopyOperation(*this, CopyConstructor);
11953 if (SetCtorInitializers(CopyConstructor, /*AnyErrors=*/false)) {
11954 CopyConstructor->setInvalidDecl();
11956 SourceLocation Loc = CopyConstructor->getLocEnd().isValid()
11957 ? CopyConstructor->getLocEnd()
11958 : CopyConstructor->getLocation();
11959 Sema::CompoundScopeRAII CompoundScope(*this);
11960 CopyConstructor->setBody(
11961 ActOnCompoundStmt(Loc, Loc, None, /*isStmtExpr=*/false).getAs<Stmt>());
11962 CopyConstructor->markUsed(Context);
11965 if (ASTMutationListener *L = getASTMutationListener()) {
11966 L->CompletedImplicitDefinition(CopyConstructor);
11970 CXXConstructorDecl *Sema::DeclareImplicitMoveConstructor(
11971 CXXRecordDecl *ClassDecl) {
11972 assert(ClassDecl->needsImplicitMoveConstructor());
11974 DeclaringSpecialMember DSM(*this, ClassDecl, CXXMoveConstructor);
11975 if (DSM.isAlreadyBeingDeclared())
11978 QualType ClassType = Context.getTypeDeclType(ClassDecl);
11979 QualType ArgType = Context.getRValueReferenceType(ClassType);
11981 bool Constexpr = defaultedSpecialMemberIsConstexpr(*this, ClassDecl,
11982 CXXMoveConstructor,
11985 DeclarationName Name
11986 = Context.DeclarationNames.getCXXConstructorName(
11987 Context.getCanonicalType(ClassType));
11988 SourceLocation ClassLoc = ClassDecl->getLocation();
11989 DeclarationNameInfo NameInfo(Name, ClassLoc);
11991 // C++11 [class.copy]p11:
11992 // An implicitly-declared copy/move constructor is an inline public
11993 // member of its class.
11994 CXXConstructorDecl *MoveConstructor = CXXConstructorDecl::Create(
11995 Context, ClassDecl, ClassLoc, NameInfo, QualType(), /*TInfo=*/nullptr,
11996 /*isExplicit=*/false, /*isInline=*/true, /*isImplicitlyDeclared=*/true,
11998 MoveConstructor->setAccess(AS_public);
11999 MoveConstructor->setDefaulted();
12001 if (getLangOpts().CUDA) {
12002 inferCUDATargetForImplicitSpecialMember(ClassDecl, CXXMoveConstructor,
12004 /* ConstRHS */ false,
12005 /* Diagnose */ false);
12008 // Build an exception specification pointing back at this member.
12009 FunctionProtoType::ExtProtoInfo EPI =
12010 getImplicitMethodEPI(*this, MoveConstructor);
12011 MoveConstructor->setType(
12012 Context.getFunctionType(Context.VoidTy, ArgType, EPI));
12014 // Add the parameter to the constructor.
12015 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, MoveConstructor,
12016 ClassLoc, ClassLoc,
12017 /*IdentifierInfo=*/nullptr,
12018 ArgType, /*TInfo=*/nullptr,
12020 MoveConstructor->setParams(FromParam);
12022 MoveConstructor->setTrivial(
12023 ClassDecl->needsOverloadResolutionForMoveConstructor()
12024 ? SpecialMemberIsTrivial(MoveConstructor, CXXMoveConstructor)
12025 : ClassDecl->hasTrivialMoveConstructor());
12027 // Note that we have declared this constructor.
12028 ++ASTContext::NumImplicitMoveConstructorsDeclared;
12030 Scope *S = getScopeForContext(ClassDecl);
12031 CheckImplicitSpecialMemberDeclaration(S, MoveConstructor);
12033 if (ShouldDeleteSpecialMember(MoveConstructor, CXXMoveConstructor)) {
12034 ClassDecl->setImplicitMoveConstructorIsDeleted();
12035 SetDeclDeleted(MoveConstructor, ClassLoc);
12039 PushOnScopeChains(MoveConstructor, S, false);
12040 ClassDecl->addDecl(MoveConstructor);
12042 return MoveConstructor;
12045 void Sema::DefineImplicitMoveConstructor(SourceLocation CurrentLocation,
12046 CXXConstructorDecl *MoveConstructor) {
12047 assert((MoveConstructor->isDefaulted() &&
12048 MoveConstructor->isMoveConstructor() &&
12049 !MoveConstructor->doesThisDeclarationHaveABody() &&
12050 !MoveConstructor->isDeleted()) &&
12051 "DefineImplicitMoveConstructor - call it for implicit move ctor");
12052 if (MoveConstructor->willHaveBody() || MoveConstructor->isInvalidDecl())
12055 CXXRecordDecl *ClassDecl = MoveConstructor->getParent();
12056 assert(ClassDecl && "DefineImplicitMoveConstructor - invalid constructor");
12058 SynthesizedFunctionScope Scope(*this, MoveConstructor);
12060 // The exception specification is needed because we are defining the
12062 ResolveExceptionSpec(CurrentLocation,
12063 MoveConstructor->getType()->castAs<FunctionProtoType>());
12064 MarkVTableUsed(CurrentLocation, ClassDecl);
12066 // Add a context note for diagnostics produced after this point.
12067 Scope.addContextNote(CurrentLocation);
12069 if (SetCtorInitializers(MoveConstructor, /*AnyErrors=*/false)) {
12070 MoveConstructor->setInvalidDecl();
12072 SourceLocation Loc = MoveConstructor->getLocEnd().isValid()
12073 ? MoveConstructor->getLocEnd()
12074 : MoveConstructor->getLocation();
12075 Sema::CompoundScopeRAII CompoundScope(*this);
12076 MoveConstructor->setBody(ActOnCompoundStmt(
12077 Loc, Loc, None, /*isStmtExpr=*/ false).getAs<Stmt>());
12078 MoveConstructor->markUsed(Context);
12081 if (ASTMutationListener *L = getASTMutationListener()) {
12082 L->CompletedImplicitDefinition(MoveConstructor);
12086 bool Sema::isImplicitlyDeleted(FunctionDecl *FD) {
12087 return FD->isDeleted() && FD->isDefaulted() && isa<CXXMethodDecl>(FD);
12090 void Sema::DefineImplicitLambdaToFunctionPointerConversion(
12091 SourceLocation CurrentLocation,
12092 CXXConversionDecl *Conv) {
12093 SynthesizedFunctionScope Scope(*this, Conv);
12095 CXXRecordDecl *Lambda = Conv->getParent();
12096 CXXMethodDecl *CallOp = Lambda->getLambdaCallOperator();
12097 // If we are defining a specialization of a conversion to function-ptr
12098 // cache the deduced template arguments for this specialization
12099 // so that we can use them to retrieve the corresponding call-operator
12100 // and static-invoker.
12101 const TemplateArgumentList *DeducedTemplateArgs = nullptr;
12103 // Retrieve the corresponding call-operator specialization.
12104 if (Lambda->isGenericLambda()) {
12105 assert(Conv->isFunctionTemplateSpecialization());
12106 FunctionTemplateDecl *CallOpTemplate =
12107 CallOp->getDescribedFunctionTemplate();
12108 DeducedTemplateArgs = Conv->getTemplateSpecializationArgs();
12109 void *InsertPos = nullptr;
12110 FunctionDecl *CallOpSpec = CallOpTemplate->findSpecialization(
12111 DeducedTemplateArgs->asArray(),
12113 assert(CallOpSpec &&
12114 "Conversion operator must have a corresponding call operator");
12115 CallOp = cast<CXXMethodDecl>(CallOpSpec);
12118 // Mark the call operator referenced (and add to pending instantiations
12120 // For both the conversion and static-invoker template specializations
12121 // we construct their body's in this function, so no need to add them
12122 // to the PendingInstantiations.
12123 MarkFunctionReferenced(CurrentLocation, CallOp);
12125 // Retrieve the static invoker...
12126 CXXMethodDecl *Invoker = Lambda->getLambdaStaticInvoker();
12127 // ... and get the corresponding specialization for a generic lambda.
12128 if (Lambda->isGenericLambda()) {
12129 assert(DeducedTemplateArgs &&
12130 "Must have deduced template arguments from Conversion Operator");
12131 FunctionTemplateDecl *InvokeTemplate =
12132 Invoker->getDescribedFunctionTemplate();
12133 void *InsertPos = nullptr;
12134 FunctionDecl *InvokeSpec = InvokeTemplate->findSpecialization(
12135 DeducedTemplateArgs->asArray(),
12137 assert(InvokeSpec &&
12138 "Must have a corresponding static invoker specialization");
12139 Invoker = cast<CXXMethodDecl>(InvokeSpec);
12141 // Construct the body of the conversion function { return __invoke; }.
12142 Expr *FunctionRef = BuildDeclRefExpr(Invoker, Invoker->getType(),
12143 VK_LValue, Conv->getLocation()).get();
12144 assert(FunctionRef && "Can't refer to __invoke function?");
12145 Stmt *Return = BuildReturnStmt(Conv->getLocation(), FunctionRef).get();
12146 Conv->setBody(new (Context) CompoundStmt(Context, Return,
12147 Conv->getLocation(),
12148 Conv->getLocation()));
12150 Conv->markUsed(Context);
12151 Conv->setReferenced();
12153 // Fill in the __invoke function with a dummy implementation. IR generation
12154 // will fill in the actual details.
12155 Invoker->markUsed(Context);
12156 Invoker->setReferenced();
12157 Invoker->setBody(new (Context) CompoundStmt(Conv->getLocation()));
12159 if (ASTMutationListener *L = getASTMutationListener()) {
12160 L->CompletedImplicitDefinition(Conv);
12161 L->CompletedImplicitDefinition(Invoker);
12167 void Sema::DefineImplicitLambdaToBlockPointerConversion(
12168 SourceLocation CurrentLocation,
12169 CXXConversionDecl *Conv)
12171 assert(!Conv->getParent()->isGenericLambda());
12173 SynthesizedFunctionScope Scope(*this, Conv);
12175 // Copy-initialize the lambda object as needed to capture it.
12176 Expr *This = ActOnCXXThis(CurrentLocation).get();
12177 Expr *DerefThis =CreateBuiltinUnaryOp(CurrentLocation, UO_Deref, This).get();
12179 ExprResult BuildBlock = BuildBlockForLambdaConversion(CurrentLocation,
12180 Conv->getLocation(),
12183 // If we're not under ARC, make sure we still get the _Block_copy/autorelease
12184 // behavior. Note that only the general conversion function does this
12185 // (since it's unusable otherwise); in the case where we inline the
12186 // block literal, it has block literal lifetime semantics.
12187 if (!BuildBlock.isInvalid() && !getLangOpts().ObjCAutoRefCount)
12188 BuildBlock = ImplicitCastExpr::Create(Context, BuildBlock.get()->getType(),
12189 CK_CopyAndAutoreleaseBlockObject,
12190 BuildBlock.get(), nullptr, VK_RValue);
12192 if (BuildBlock.isInvalid()) {
12193 Diag(CurrentLocation, diag::note_lambda_to_block_conv);
12194 Conv->setInvalidDecl();
12198 // Create the return statement that returns the block from the conversion
12200 StmtResult Return = BuildReturnStmt(Conv->getLocation(), BuildBlock.get());
12201 if (Return.isInvalid()) {
12202 Diag(CurrentLocation, diag::note_lambda_to_block_conv);
12203 Conv->setInvalidDecl();
12207 // Set the body of the conversion function.
12208 Stmt *ReturnS = Return.get();
12209 Conv->setBody(new (Context) CompoundStmt(Context, ReturnS,
12210 Conv->getLocation(),
12211 Conv->getLocation()));
12212 Conv->markUsed(Context);
12214 // We're done; notify the mutation listener, if any.
12215 if (ASTMutationListener *L = getASTMutationListener()) {
12216 L->CompletedImplicitDefinition(Conv);
12220 /// \brief Determine whether the given list arguments contains exactly one
12221 /// "real" (non-default) argument.
12222 static bool hasOneRealArgument(MultiExprArg Args) {
12223 switch (Args.size()) {
12228 if (!Args[1]->isDefaultArgument())
12233 return !Args[0]->isDefaultArgument();
12240 Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
12241 NamedDecl *FoundDecl,
12242 CXXConstructorDecl *Constructor,
12243 MultiExprArg ExprArgs,
12244 bool HadMultipleCandidates,
12245 bool IsListInitialization,
12246 bool IsStdInitListInitialization,
12247 bool RequiresZeroInit,
12248 unsigned ConstructKind,
12249 SourceRange ParenRange) {
12250 bool Elidable = false;
12252 // C++0x [class.copy]p34:
12253 // When certain criteria are met, an implementation is allowed to
12254 // omit the copy/move construction of a class object, even if the
12255 // copy/move constructor and/or destructor for the object have
12256 // side effects. [...]
12257 // - when a temporary class object that has not been bound to a
12258 // reference (12.2) would be copied/moved to a class object
12259 // with the same cv-unqualified type, the copy/move operation
12260 // can be omitted by constructing the temporary object
12261 // directly into the target of the omitted copy/move
12262 if (ConstructKind == CXXConstructExpr::CK_Complete && Constructor &&
12263 Constructor->isCopyOrMoveConstructor() && hasOneRealArgument(ExprArgs)) {
12264 Expr *SubExpr = ExprArgs[0];
12265 Elidable = SubExpr->isTemporaryObject(
12266 Context, cast<CXXRecordDecl>(FoundDecl->getDeclContext()));
12269 return BuildCXXConstructExpr(ConstructLoc, DeclInitType,
12270 FoundDecl, Constructor,
12271 Elidable, ExprArgs, HadMultipleCandidates,
12272 IsListInitialization,
12273 IsStdInitListInitialization, RequiresZeroInit,
12274 ConstructKind, ParenRange);
12278 Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
12279 NamedDecl *FoundDecl,
12280 CXXConstructorDecl *Constructor,
12282 MultiExprArg ExprArgs,
12283 bool HadMultipleCandidates,
12284 bool IsListInitialization,
12285 bool IsStdInitListInitialization,
12286 bool RequiresZeroInit,
12287 unsigned ConstructKind,
12288 SourceRange ParenRange) {
12289 if (auto *Shadow = dyn_cast<ConstructorUsingShadowDecl>(FoundDecl)) {
12290 Constructor = findInheritingConstructor(ConstructLoc, Constructor, Shadow);
12291 if (DiagnoseUseOfDecl(Constructor, ConstructLoc))
12292 return ExprError();
12295 return BuildCXXConstructExpr(
12296 ConstructLoc, DeclInitType, Constructor, Elidable, ExprArgs,
12297 HadMultipleCandidates, IsListInitialization, IsStdInitListInitialization,
12298 RequiresZeroInit, ConstructKind, ParenRange);
12301 /// BuildCXXConstructExpr - Creates a complete call to a constructor,
12302 /// including handling of its default argument expressions.
12304 Sema::BuildCXXConstructExpr(SourceLocation ConstructLoc, QualType DeclInitType,
12305 CXXConstructorDecl *Constructor,
12307 MultiExprArg ExprArgs,
12308 bool HadMultipleCandidates,
12309 bool IsListInitialization,
12310 bool IsStdInitListInitialization,
12311 bool RequiresZeroInit,
12312 unsigned ConstructKind,
12313 SourceRange ParenRange) {
12314 assert(declaresSameEntity(
12315 Constructor->getParent(),
12316 DeclInitType->getBaseElementTypeUnsafe()->getAsCXXRecordDecl()) &&
12317 "given constructor for wrong type");
12318 MarkFunctionReferenced(ConstructLoc, Constructor);
12319 if (getLangOpts().CUDA && !CheckCUDACall(ConstructLoc, Constructor))
12320 return ExprError();
12322 return CXXConstructExpr::Create(
12323 Context, DeclInitType, ConstructLoc, Constructor, Elidable,
12324 ExprArgs, HadMultipleCandidates, IsListInitialization,
12325 IsStdInitListInitialization, RequiresZeroInit,
12326 static_cast<CXXConstructExpr::ConstructionKind>(ConstructKind),
12330 ExprResult Sema::BuildCXXDefaultInitExpr(SourceLocation Loc, FieldDecl *Field) {
12331 assert(Field->hasInClassInitializer());
12333 // If we already have the in-class initializer nothing needs to be done.
12334 if (Field->getInClassInitializer())
12335 return CXXDefaultInitExpr::Create(Context, Loc, Field);
12337 // If we might have already tried and failed to instantiate, don't try again.
12338 if (Field->isInvalidDecl())
12339 return ExprError();
12341 // Maybe we haven't instantiated the in-class initializer. Go check the
12342 // pattern FieldDecl to see if it has one.
12343 CXXRecordDecl *ParentRD = cast<CXXRecordDecl>(Field->getParent());
12345 if (isTemplateInstantiation(ParentRD->getTemplateSpecializationKind())) {
12346 CXXRecordDecl *ClassPattern = ParentRD->getTemplateInstantiationPattern();
12347 DeclContext::lookup_result Lookup =
12348 ClassPattern->lookup(Field->getDeclName());
12350 // Lookup can return at most two results: the pattern for the field, or the
12351 // injected class name of the parent record. No other member can have the
12352 // same name as the field.
12353 // In modules mode, lookup can return multiple results (coming from
12354 // different modules).
12355 assert((getLangOpts().Modules || (!Lookup.empty() && Lookup.size() <= 2)) &&
12356 "more than two lookup results for field name");
12357 FieldDecl *Pattern = dyn_cast<FieldDecl>(Lookup[0]);
12359 assert(isa<CXXRecordDecl>(Lookup[0]) &&
12360 "cannot have other non-field member with same name");
12361 for (auto L : Lookup)
12362 if (isa<FieldDecl>(L)) {
12363 Pattern = cast<FieldDecl>(L);
12366 assert(Pattern && "We must have set the Pattern!");
12369 if (InstantiateInClassInitializer(Loc, Field, Pattern,
12370 getTemplateInstantiationArgs(Field))) {
12371 // Don't diagnose this again.
12372 Field->setInvalidDecl();
12373 return ExprError();
12375 return CXXDefaultInitExpr::Create(Context, Loc, Field);
12379 // If the brace-or-equal-initializer of a non-static data member
12380 // invokes a defaulted default constructor of its class or of an
12381 // enclosing class in a potentially evaluated subexpression, the
12382 // program is ill-formed.
12384 // This resolution is unworkable: the exception specification of the
12385 // default constructor can be needed in an unevaluated context, in
12386 // particular, in the operand of a noexcept-expression, and we can be
12387 // unable to compute an exception specification for an enclosed class.
12389 // Any attempt to resolve the exception specification of a defaulted default
12390 // constructor before the initializer is lexically complete will ultimately
12391 // come here at which point we can diagnose it.
12392 RecordDecl *OutermostClass = ParentRD->getOuterLexicalRecordContext();
12393 Diag(Loc, diag::err_in_class_initializer_not_yet_parsed)
12394 << OutermostClass << Field;
12395 Diag(Field->getLocEnd(), diag::note_in_class_initializer_not_yet_parsed);
12396 // Recover by marking the field invalid, unless we're in a SFINAE context.
12397 if (!isSFINAEContext())
12398 Field->setInvalidDecl();
12399 return ExprError();
12402 void Sema::FinalizeVarWithDestructor(VarDecl *VD, const RecordType *Record) {
12403 if (VD->isInvalidDecl()) return;
12405 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Record->getDecl());
12406 if (ClassDecl->isInvalidDecl()) return;
12407 if (ClassDecl->hasIrrelevantDestructor()) return;
12408 if (ClassDecl->isDependentContext()) return;
12410 CXXDestructorDecl *Destructor = LookupDestructor(ClassDecl);
12411 MarkFunctionReferenced(VD->getLocation(), Destructor);
12412 CheckDestructorAccess(VD->getLocation(), Destructor,
12413 PDiag(diag::err_access_dtor_var)
12414 << VD->getDeclName()
12416 DiagnoseUseOfDecl(Destructor, VD->getLocation());
12418 if (Destructor->isTrivial()) return;
12419 if (!VD->hasGlobalStorage()) return;
12421 // Emit warning for non-trivial dtor in global scope (a real global,
12422 // class-static, function-static).
12423 Diag(VD->getLocation(), diag::warn_exit_time_destructor);
12425 // TODO: this should be re-enabled for static locals by !CXAAtExit
12426 if (!VD->isStaticLocal())
12427 Diag(VD->getLocation(), diag::warn_global_destructor);
12430 /// \brief Given a constructor and the set of arguments provided for the
12431 /// constructor, convert the arguments and add any required default arguments
12432 /// to form a proper call to this constructor.
12434 /// \returns true if an error occurred, false otherwise.
12436 Sema::CompleteConstructorCall(CXXConstructorDecl *Constructor,
12437 MultiExprArg ArgsPtr,
12438 SourceLocation Loc,
12439 SmallVectorImpl<Expr*> &ConvertedArgs,
12440 bool AllowExplicit,
12441 bool IsListInitialization) {
12442 // FIXME: This duplicates a lot of code from Sema::ConvertArgumentsForCall.
12443 unsigned NumArgs = ArgsPtr.size();
12444 Expr **Args = ArgsPtr.data();
12446 const FunctionProtoType *Proto
12447 = Constructor->getType()->getAs<FunctionProtoType>();
12448 assert(Proto && "Constructor without a prototype?");
12449 unsigned NumParams = Proto->getNumParams();
12451 // If too few arguments are available, we'll fill in the rest with defaults.
12452 if (NumArgs < NumParams)
12453 ConvertedArgs.reserve(NumParams);
12455 ConvertedArgs.reserve(NumArgs);
12457 VariadicCallType CallType =
12458 Proto->isVariadic() ? VariadicConstructor : VariadicDoesNotApply;
12459 SmallVector<Expr *, 8> AllArgs;
12460 bool Invalid = GatherArgumentsForCall(Loc, Constructor,
12462 llvm::makeArrayRef(Args, NumArgs),
12464 CallType, AllowExplicit,
12465 IsListInitialization);
12466 ConvertedArgs.append(AllArgs.begin(), AllArgs.end());
12468 DiagnoseSentinelCalls(Constructor, Loc, AllArgs);
12470 CheckConstructorCall(Constructor,
12471 llvm::makeArrayRef(AllArgs.data(), AllArgs.size()),
12478 CheckOperatorNewDeleteDeclarationScope(Sema &SemaRef,
12479 const FunctionDecl *FnDecl) {
12480 const DeclContext *DC = FnDecl->getDeclContext()->getRedeclContext();
12481 if (isa<NamespaceDecl>(DC)) {
12482 return SemaRef.Diag(FnDecl->getLocation(),
12483 diag::err_operator_new_delete_declared_in_namespace)
12484 << FnDecl->getDeclName();
12487 if (isa<TranslationUnitDecl>(DC) &&
12488 FnDecl->getStorageClass() == SC_Static) {
12489 return SemaRef.Diag(FnDecl->getLocation(),
12490 diag::err_operator_new_delete_declared_static)
12491 << FnDecl->getDeclName();
12498 CheckOperatorNewDeleteTypes(Sema &SemaRef, const FunctionDecl *FnDecl,
12499 CanQualType ExpectedResultType,
12500 CanQualType ExpectedFirstParamType,
12501 unsigned DependentParamTypeDiag,
12502 unsigned InvalidParamTypeDiag) {
12503 QualType ResultType =
12504 FnDecl->getType()->getAs<FunctionType>()->getReturnType();
12506 // Check that the result type is not dependent.
12507 if (ResultType->isDependentType())
12508 return SemaRef.Diag(FnDecl->getLocation(),
12509 diag::err_operator_new_delete_dependent_result_type)
12510 << FnDecl->getDeclName() << ExpectedResultType;
12512 // Check that the result type is what we expect.
12513 if (SemaRef.Context.getCanonicalType(ResultType) != ExpectedResultType)
12514 return SemaRef.Diag(FnDecl->getLocation(),
12515 diag::err_operator_new_delete_invalid_result_type)
12516 << FnDecl->getDeclName() << ExpectedResultType;
12518 // A function template must have at least 2 parameters.
12519 if (FnDecl->getDescribedFunctionTemplate() && FnDecl->getNumParams() < 2)
12520 return SemaRef.Diag(FnDecl->getLocation(),
12521 diag::err_operator_new_delete_template_too_few_parameters)
12522 << FnDecl->getDeclName();
12524 // The function decl must have at least 1 parameter.
12525 if (FnDecl->getNumParams() == 0)
12526 return SemaRef.Diag(FnDecl->getLocation(),
12527 diag::err_operator_new_delete_too_few_parameters)
12528 << FnDecl->getDeclName();
12530 // Check the first parameter type is not dependent.
12531 QualType FirstParamType = FnDecl->getParamDecl(0)->getType();
12532 if (FirstParamType->isDependentType())
12533 return SemaRef.Diag(FnDecl->getLocation(), DependentParamTypeDiag)
12534 << FnDecl->getDeclName() << ExpectedFirstParamType;
12536 // Check that the first parameter type is what we expect.
12537 if (SemaRef.Context.getCanonicalType(FirstParamType).getUnqualifiedType() !=
12538 ExpectedFirstParamType)
12539 return SemaRef.Diag(FnDecl->getLocation(), InvalidParamTypeDiag)
12540 << FnDecl->getDeclName() << ExpectedFirstParamType;
12546 CheckOperatorNewDeclaration(Sema &SemaRef, const FunctionDecl *FnDecl) {
12547 // C++ [basic.stc.dynamic.allocation]p1:
12548 // A program is ill-formed if an allocation function is declared in a
12549 // namespace scope other than global scope or declared static in global
12551 if (CheckOperatorNewDeleteDeclarationScope(SemaRef, FnDecl))
12554 CanQualType SizeTy =
12555 SemaRef.Context.getCanonicalType(SemaRef.Context.getSizeType());
12557 // C++ [basic.stc.dynamic.allocation]p1:
12558 // The return type shall be void*. The first parameter shall have type
12560 if (CheckOperatorNewDeleteTypes(SemaRef, FnDecl, SemaRef.Context.VoidPtrTy,
12562 diag::err_operator_new_dependent_param_type,
12563 diag::err_operator_new_param_type))
12566 // C++ [basic.stc.dynamic.allocation]p1:
12567 // The first parameter shall not have an associated default argument.
12568 if (FnDecl->getParamDecl(0)->hasDefaultArg())
12569 return SemaRef.Diag(FnDecl->getLocation(),
12570 diag::err_operator_new_default_arg)
12571 << FnDecl->getDeclName() << FnDecl->getParamDecl(0)->getDefaultArgRange();
12577 CheckOperatorDeleteDeclaration(Sema &SemaRef, FunctionDecl *FnDecl) {
12578 // C++ [basic.stc.dynamic.deallocation]p1:
12579 // A program is ill-formed if deallocation functions are declared in a
12580 // namespace scope other than global scope or declared static in global
12582 if (CheckOperatorNewDeleteDeclarationScope(SemaRef, FnDecl))
12585 // C++ [basic.stc.dynamic.deallocation]p2:
12586 // Each deallocation function shall return void and its first parameter
12588 if (CheckOperatorNewDeleteTypes(SemaRef, FnDecl, SemaRef.Context.VoidTy,
12589 SemaRef.Context.VoidPtrTy,
12590 diag::err_operator_delete_dependent_param_type,
12591 diag::err_operator_delete_param_type))
12597 /// CheckOverloadedOperatorDeclaration - Check whether the declaration
12598 /// of this overloaded operator is well-formed. If so, returns false;
12599 /// otherwise, emits appropriate diagnostics and returns true.
12600 bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) {
12601 assert(FnDecl && FnDecl->isOverloadedOperator() &&
12602 "Expected an overloaded operator declaration");
12604 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator();
12606 // C++ [over.oper]p5:
12607 // The allocation and deallocation functions, operator new,
12608 // operator new[], operator delete and operator delete[], are
12609 // described completely in 3.7.3. The attributes and restrictions
12610 // found in the rest of this subclause do not apply to them unless
12611 // explicitly stated in 3.7.3.
12612 if (Op == OO_Delete || Op == OO_Array_Delete)
12613 return CheckOperatorDeleteDeclaration(*this, FnDecl);
12615 if (Op == OO_New || Op == OO_Array_New)
12616 return CheckOperatorNewDeclaration(*this, FnDecl);
12618 // C++ [over.oper]p6:
12619 // An operator function shall either be a non-static member
12620 // function or be a non-member function and have at least one
12621 // parameter whose type is a class, a reference to a class, an
12622 // enumeration, or a reference to an enumeration.
12623 if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl)) {
12624 if (MethodDecl->isStatic())
12625 return Diag(FnDecl->getLocation(),
12626 diag::err_operator_overload_static) << FnDecl->getDeclName();
12628 bool ClassOrEnumParam = false;
12629 for (auto Param : FnDecl->parameters()) {
12630 QualType ParamType = Param->getType().getNonReferenceType();
12631 if (ParamType->isDependentType() || ParamType->isRecordType() ||
12632 ParamType->isEnumeralType()) {
12633 ClassOrEnumParam = true;
12638 if (!ClassOrEnumParam)
12639 return Diag(FnDecl->getLocation(),
12640 diag::err_operator_overload_needs_class_or_enum)
12641 << FnDecl->getDeclName();
12644 // C++ [over.oper]p8:
12645 // An operator function cannot have default arguments (8.3.6),
12646 // except where explicitly stated below.
12648 // Only the function-call operator allows default arguments
12649 // (C++ [over.call]p1).
12650 if (Op != OO_Call) {
12651 for (auto Param : FnDecl->parameters()) {
12652 if (Param->hasDefaultArg())
12653 return Diag(Param->getLocation(),
12654 diag::err_operator_overload_default_arg)
12655 << FnDecl->getDeclName() << Param->getDefaultArgRange();
12659 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = {
12660 { false, false, false }
12661 #define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \
12662 , { Unary, Binary, MemberOnly }
12663 #include "clang/Basic/OperatorKinds.def"
12666 bool CanBeUnaryOperator = OperatorUses[Op][0];
12667 bool CanBeBinaryOperator = OperatorUses[Op][1];
12668 bool MustBeMemberOperator = OperatorUses[Op][2];
12670 // C++ [over.oper]p8:
12671 // [...] Operator functions cannot have more or fewer parameters
12672 // than the number required for the corresponding operator, as
12673 // described in the rest of this subclause.
12674 unsigned NumParams = FnDecl->getNumParams()
12675 + (isa<CXXMethodDecl>(FnDecl)? 1 : 0);
12676 if (Op != OO_Call &&
12677 ((NumParams == 1 && !CanBeUnaryOperator) ||
12678 (NumParams == 2 && !CanBeBinaryOperator) ||
12679 (NumParams < 1) || (NumParams > 2))) {
12680 // We have the wrong number of parameters.
12681 unsigned ErrorKind;
12682 if (CanBeUnaryOperator && CanBeBinaryOperator) {
12683 ErrorKind = 2; // 2 -> unary or binary.
12684 } else if (CanBeUnaryOperator) {
12685 ErrorKind = 0; // 0 -> unary
12687 assert(CanBeBinaryOperator &&
12688 "All non-call overloaded operators are unary or binary!");
12689 ErrorKind = 1; // 1 -> binary
12692 return Diag(FnDecl->getLocation(), diag::err_operator_overload_must_be)
12693 << FnDecl->getDeclName() << NumParams << ErrorKind;
12696 // Overloaded operators other than operator() cannot be variadic.
12697 if (Op != OO_Call &&
12698 FnDecl->getType()->getAs<FunctionProtoType>()->isVariadic()) {
12699 return Diag(FnDecl->getLocation(), diag::err_operator_overload_variadic)
12700 << FnDecl->getDeclName();
12703 // Some operators must be non-static member functions.
12704 if (MustBeMemberOperator && !isa<CXXMethodDecl>(FnDecl)) {
12705 return Diag(FnDecl->getLocation(),
12706 diag::err_operator_overload_must_be_member)
12707 << FnDecl->getDeclName();
12710 // C++ [over.inc]p1:
12711 // The user-defined function called operator++ implements the
12712 // prefix and postfix ++ operator. If this function is a member
12713 // function with no parameters, or a non-member function with one
12714 // parameter of class or enumeration type, it defines the prefix
12715 // increment operator ++ for objects of that type. If the function
12716 // is a member function with one parameter (which shall be of type
12717 // int) or a non-member function with two parameters (the second
12718 // of which shall be of type int), it defines the postfix
12719 // increment operator ++ for objects of that type.
12720 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) {
12721 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1);
12722 QualType ParamType = LastParam->getType();
12724 if (!ParamType->isSpecificBuiltinType(BuiltinType::Int) &&
12725 !ParamType->isDependentType())
12726 return Diag(LastParam->getLocation(),
12727 diag::err_operator_overload_post_incdec_must_be_int)
12728 << LastParam->getType() << (Op == OO_MinusMinus);
12735 checkLiteralOperatorTemplateParameterList(Sema &SemaRef,
12736 FunctionTemplateDecl *TpDecl) {
12737 TemplateParameterList *TemplateParams = TpDecl->getTemplateParameters();
12739 // Must have one or two template parameters.
12740 if (TemplateParams->size() == 1) {
12741 NonTypeTemplateParmDecl *PmDecl =
12742 dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(0));
12744 // The template parameter must be a char parameter pack.
12745 if (PmDecl && PmDecl->isTemplateParameterPack() &&
12746 SemaRef.Context.hasSameType(PmDecl->getType(), SemaRef.Context.CharTy))
12749 } else if (TemplateParams->size() == 2) {
12750 TemplateTypeParmDecl *PmType =
12751 dyn_cast<TemplateTypeParmDecl>(TemplateParams->getParam(0));
12752 NonTypeTemplateParmDecl *PmArgs =
12753 dyn_cast<NonTypeTemplateParmDecl>(TemplateParams->getParam(1));
12755 // The second template parameter must be a parameter pack with the
12756 // first template parameter as its type.
12757 if (PmType && PmArgs && !PmType->isTemplateParameterPack() &&
12758 PmArgs->isTemplateParameterPack()) {
12759 const TemplateTypeParmType *TArgs =
12760 PmArgs->getType()->getAs<TemplateTypeParmType>();
12761 if (TArgs && TArgs->getDepth() == PmType->getDepth() &&
12762 TArgs->getIndex() == PmType->getIndex()) {
12763 if (!SemaRef.inTemplateInstantiation())
12764 SemaRef.Diag(TpDecl->getLocation(),
12765 diag::ext_string_literal_operator_template);
12771 SemaRef.Diag(TpDecl->getTemplateParameters()->getSourceRange().getBegin(),
12772 diag::err_literal_operator_template)
12773 << TpDecl->getTemplateParameters()->getSourceRange();
12777 /// CheckLiteralOperatorDeclaration - Check whether the declaration
12778 /// of this literal operator function is well-formed. If so, returns
12779 /// false; otherwise, emits appropriate diagnostics and returns true.
12780 bool Sema::CheckLiteralOperatorDeclaration(FunctionDecl *FnDecl) {
12781 if (isa<CXXMethodDecl>(FnDecl)) {
12782 Diag(FnDecl->getLocation(), diag::err_literal_operator_outside_namespace)
12783 << FnDecl->getDeclName();
12787 if (FnDecl->isExternC()) {
12788 Diag(FnDecl->getLocation(), diag::err_literal_operator_extern_c);
12789 if (const LinkageSpecDecl *LSD =
12790 FnDecl->getDeclContext()->getExternCContext())
12791 Diag(LSD->getExternLoc(), diag::note_extern_c_begins_here);
12795 // This might be the definition of a literal operator template.
12796 FunctionTemplateDecl *TpDecl = FnDecl->getDescribedFunctionTemplate();
12798 // This might be a specialization of a literal operator template.
12800 TpDecl = FnDecl->getPrimaryTemplate();
12802 // template <char...> type operator "" name() and
12803 // template <class T, T...> type operator "" name() are the only valid
12804 // template signatures, and the only valid signatures with no parameters.
12806 if (FnDecl->param_size() != 0) {
12807 Diag(FnDecl->getLocation(),
12808 diag::err_literal_operator_template_with_params);
12812 if (checkLiteralOperatorTemplateParameterList(*this, TpDecl))
12815 } else if (FnDecl->param_size() == 1) {
12816 const ParmVarDecl *Param = FnDecl->getParamDecl(0);
12818 QualType ParamType = Param->getType().getUnqualifiedType();
12820 // Only unsigned long long int, long double, any character type, and const
12821 // char * are allowed as the only parameters.
12822 if (ParamType->isSpecificBuiltinType(BuiltinType::ULongLong) ||
12823 ParamType->isSpecificBuiltinType(BuiltinType::LongDouble) ||
12824 Context.hasSameType(ParamType, Context.CharTy) ||
12825 Context.hasSameType(ParamType, Context.WideCharTy) ||
12826 Context.hasSameType(ParamType, Context.Char16Ty) ||
12827 Context.hasSameType(ParamType, Context.Char32Ty)) {
12828 } else if (const PointerType *Ptr = ParamType->getAs<PointerType>()) {
12829 QualType InnerType = Ptr->getPointeeType();
12831 // Pointer parameter must be a const char *.
12832 if (!(Context.hasSameType(InnerType.getUnqualifiedType(),
12834 InnerType.isConstQualified() && !InnerType.isVolatileQualified())) {
12835 Diag(Param->getSourceRange().getBegin(),
12836 diag::err_literal_operator_param)
12837 << ParamType << "'const char *'" << Param->getSourceRange();
12841 } else if (ParamType->isRealFloatingType()) {
12842 Diag(Param->getSourceRange().getBegin(), diag::err_literal_operator_param)
12843 << ParamType << Context.LongDoubleTy << Param->getSourceRange();
12846 } else if (ParamType->isIntegerType()) {
12847 Diag(Param->getSourceRange().getBegin(), diag::err_literal_operator_param)
12848 << ParamType << Context.UnsignedLongLongTy << Param->getSourceRange();
12852 Diag(Param->getSourceRange().getBegin(),
12853 diag::err_literal_operator_invalid_param)
12854 << ParamType << Param->getSourceRange();
12858 } else if (FnDecl->param_size() == 2) {
12859 FunctionDecl::param_iterator Param = FnDecl->param_begin();
12861 // First, verify that the first parameter is correct.
12863 QualType FirstParamType = (*Param)->getType().getUnqualifiedType();
12865 // Two parameter function must have a pointer to const as a
12866 // first parameter; let's strip those qualifiers.
12867 const PointerType *PT = FirstParamType->getAs<PointerType>();
12870 Diag((*Param)->getSourceRange().getBegin(),
12871 diag::err_literal_operator_param)
12872 << FirstParamType << "'const char *'" << (*Param)->getSourceRange();
12876 QualType PointeeType = PT->getPointeeType();
12877 // First parameter must be const
12878 if (!PointeeType.isConstQualified() || PointeeType.isVolatileQualified()) {
12879 Diag((*Param)->getSourceRange().getBegin(),
12880 diag::err_literal_operator_param)
12881 << FirstParamType << "'const char *'" << (*Param)->getSourceRange();
12885 QualType InnerType = PointeeType.getUnqualifiedType();
12886 // Only const char *, const wchar_t*, const char16_t*, and const char32_t*
12887 // are allowed as the first parameter to a two-parameter function
12888 if (!(Context.hasSameType(InnerType, Context.CharTy) ||
12889 Context.hasSameType(InnerType, Context.WideCharTy) ||
12890 Context.hasSameType(InnerType, Context.Char16Ty) ||
12891 Context.hasSameType(InnerType, Context.Char32Ty))) {
12892 Diag((*Param)->getSourceRange().getBegin(),
12893 diag::err_literal_operator_param)
12894 << FirstParamType << "'const char *'" << (*Param)->getSourceRange();
12898 // Move on to the second and final parameter.
12901 // The second parameter must be a std::size_t.
12902 QualType SecondParamType = (*Param)->getType().getUnqualifiedType();
12903 if (!Context.hasSameType(SecondParamType, Context.getSizeType())) {
12904 Diag((*Param)->getSourceRange().getBegin(),
12905 diag::err_literal_operator_param)
12906 << SecondParamType << Context.getSizeType()
12907 << (*Param)->getSourceRange();
12911 Diag(FnDecl->getLocation(), diag::err_literal_operator_bad_param_count);
12915 // Parameters are good.
12917 // A parameter-declaration-clause containing a default argument is not
12918 // equivalent to any of the permitted forms.
12919 for (auto Param : FnDecl->parameters()) {
12920 if (Param->hasDefaultArg()) {
12921 Diag(Param->getDefaultArgRange().getBegin(),
12922 diag::err_literal_operator_default_argument)
12923 << Param->getDefaultArgRange();
12928 StringRef LiteralName
12929 = FnDecl->getDeclName().getCXXLiteralIdentifier()->getName();
12930 if (LiteralName[0] != '_') {
12931 // C++11 [usrlit.suffix]p1:
12932 // Literal suffix identifiers that do not start with an underscore
12933 // are reserved for future standardization.
12934 Diag(FnDecl->getLocation(), diag::warn_user_literal_reserved)
12935 << StringLiteralParser::isValidUDSuffix(getLangOpts(), LiteralName);
12941 /// ActOnStartLinkageSpecification - Parsed the beginning of a C++
12942 /// linkage specification, including the language and (if present)
12943 /// the '{'. ExternLoc is the location of the 'extern', Lang is the
12944 /// language string literal. LBraceLoc, if valid, provides the location of
12945 /// the '{' brace. Otherwise, this linkage specification does not
12946 /// have any braces.
12947 Decl *Sema::ActOnStartLinkageSpecification(Scope *S, SourceLocation ExternLoc,
12949 SourceLocation LBraceLoc) {
12950 StringLiteral *Lit = cast<StringLiteral>(LangStr);
12951 if (!Lit->isAscii()) {
12952 Diag(LangStr->getExprLoc(), diag::err_language_linkage_spec_not_ascii)
12953 << LangStr->getSourceRange();
12957 StringRef Lang = Lit->getString();
12958 LinkageSpecDecl::LanguageIDs Language;
12960 Language = LinkageSpecDecl::lang_c;
12961 else if (Lang == "C++")
12962 Language = LinkageSpecDecl::lang_cxx;
12964 Diag(LangStr->getExprLoc(), diag::err_language_linkage_spec_unknown)
12965 << LangStr->getSourceRange();
12969 // FIXME: Add all the various semantics of linkage specifications
12971 LinkageSpecDecl *D = LinkageSpecDecl::Create(Context, CurContext, ExternLoc,
12972 LangStr->getExprLoc(), Language,
12973 LBraceLoc.isValid());
12974 CurContext->addDecl(D);
12975 PushDeclContext(S, D);
12979 /// ActOnFinishLinkageSpecification - Complete the definition of
12980 /// the C++ linkage specification LinkageSpec. If RBraceLoc is
12981 /// valid, it's the position of the closing '}' brace in a linkage
12982 /// specification that uses braces.
12983 Decl *Sema::ActOnFinishLinkageSpecification(Scope *S,
12985 SourceLocation RBraceLoc) {
12986 if (RBraceLoc.isValid()) {
12987 LinkageSpecDecl* LSDecl = cast<LinkageSpecDecl>(LinkageSpec);
12988 LSDecl->setRBraceLoc(RBraceLoc);
12991 return LinkageSpec;
12994 Decl *Sema::ActOnEmptyDeclaration(Scope *S,
12995 AttributeList *AttrList,
12996 SourceLocation SemiLoc) {
12997 Decl *ED = EmptyDecl::Create(Context, CurContext, SemiLoc);
12998 // Attribute declarations appertain to empty declaration so we handle
13001 ProcessDeclAttributeList(S, ED, AttrList);
13003 CurContext->addDecl(ED);
13007 /// \brief Perform semantic analysis for the variable declaration that
13008 /// occurs within a C++ catch clause, returning the newly-created
13010 VarDecl *Sema::BuildExceptionDeclaration(Scope *S,
13011 TypeSourceInfo *TInfo,
13012 SourceLocation StartLoc,
13013 SourceLocation Loc,
13014 IdentifierInfo *Name) {
13015 bool Invalid = false;
13016 QualType ExDeclType = TInfo->getType();
13018 // Arrays and functions decay.
13019 if (ExDeclType->isArrayType())
13020 ExDeclType = Context.getArrayDecayedType(ExDeclType);
13021 else if (ExDeclType->isFunctionType())
13022 ExDeclType = Context.getPointerType(ExDeclType);
13024 // C++ 15.3p1: The exception-declaration shall not denote an incomplete type.
13025 // The exception-declaration shall not denote a pointer or reference to an
13026 // incomplete type, other than [cv] void*.
13027 // N2844 forbids rvalue references.
13028 if (!ExDeclType->isDependentType() && ExDeclType->isRValueReferenceType()) {
13029 Diag(Loc, diag::err_catch_rvalue_ref);
13033 if (ExDeclType->isVariablyModifiedType()) {
13034 Diag(Loc, diag::err_catch_variably_modified) << ExDeclType;
13038 QualType BaseType = ExDeclType;
13039 int Mode = 0; // 0 for direct type, 1 for pointer, 2 for reference
13040 unsigned DK = diag::err_catch_incomplete;
13041 if (const PointerType *Ptr = BaseType->getAs<PointerType>()) {
13042 BaseType = Ptr->getPointeeType();
13044 DK = diag::err_catch_incomplete_ptr;
13045 } else if (const ReferenceType *Ref = BaseType->getAs<ReferenceType>()) {
13046 // For the purpose of error recovery, we treat rvalue refs like lvalue refs.
13047 BaseType = Ref->getPointeeType();
13049 DK = diag::err_catch_incomplete_ref;
13051 if (!Invalid && (Mode == 0 || !BaseType->isVoidType()) &&
13052 !BaseType->isDependentType() && RequireCompleteType(Loc, BaseType, DK))
13055 if (!Invalid && !ExDeclType->isDependentType() &&
13056 RequireNonAbstractType(Loc, ExDeclType,
13057 diag::err_abstract_type_in_decl,
13058 AbstractVariableType))
13061 // Only the non-fragile NeXT runtime currently supports C++ catches
13062 // of ObjC types, and no runtime supports catching ObjC types by value.
13063 if (!Invalid && getLangOpts().ObjC1) {
13064 QualType T = ExDeclType;
13065 if (const ReferenceType *RT = T->getAs<ReferenceType>())
13066 T = RT->getPointeeType();
13068 if (T->isObjCObjectType()) {
13069 Diag(Loc, diag::err_objc_object_catch);
13071 } else if (T->isObjCObjectPointerType()) {
13072 // FIXME: should this be a test for macosx-fragile specifically?
13073 if (getLangOpts().ObjCRuntime.isFragile())
13074 Diag(Loc, diag::warn_objc_pointer_cxx_catch_fragile);
13078 VarDecl *ExDecl = VarDecl::Create(Context, CurContext, StartLoc, Loc, Name,
13079 ExDeclType, TInfo, SC_None);
13080 ExDecl->setExceptionVariable(true);
13082 // In ARC, infer 'retaining' for variables of retainable type.
13083 if (getLangOpts().ObjCAutoRefCount && inferObjCARCLifetime(ExDecl))
13086 if (!Invalid && !ExDeclType->isDependentType()) {
13087 if (const RecordType *recordType = ExDeclType->getAs<RecordType>()) {
13088 // Insulate this from anything else we might currently be parsing.
13089 EnterExpressionEvaluationContext scope(
13090 *this, ExpressionEvaluationContext::PotentiallyEvaluated);
13092 // C++ [except.handle]p16:
13093 // The object declared in an exception-declaration or, if the
13094 // exception-declaration does not specify a name, a temporary (12.2) is
13095 // copy-initialized (8.5) from the exception object. [...]
13096 // The object is destroyed when the handler exits, after the destruction
13097 // of any automatic objects initialized within the handler.
13099 // We just pretend to initialize the object with itself, then make sure
13100 // it can be destroyed later.
13101 QualType initType = Context.getExceptionObjectType(ExDeclType);
13103 InitializedEntity entity =
13104 InitializedEntity::InitializeVariable(ExDecl);
13105 InitializationKind initKind =
13106 InitializationKind::CreateCopy(Loc, SourceLocation());
13108 Expr *opaqueValue =
13109 new (Context) OpaqueValueExpr(Loc, initType, VK_LValue, OK_Ordinary);
13110 InitializationSequence sequence(*this, entity, initKind, opaqueValue);
13111 ExprResult result = sequence.Perform(*this, entity, initKind, opaqueValue);
13112 if (result.isInvalid())
13115 // If the constructor used was non-trivial, set this as the
13117 CXXConstructExpr *construct = result.getAs<CXXConstructExpr>();
13118 if (!construct->getConstructor()->isTrivial()) {
13119 Expr *init = MaybeCreateExprWithCleanups(construct);
13120 ExDecl->setInit(init);
13123 // And make sure it's destructable.
13124 FinalizeVarWithDestructor(ExDecl, recordType);
13130 ExDecl->setInvalidDecl();
13135 /// ActOnExceptionDeclarator - Parsed the exception-declarator in a C++ catch
13137 Decl *Sema::ActOnExceptionDeclarator(Scope *S, Declarator &D) {
13138 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
13139 bool Invalid = D.isInvalidType();
13141 // Check for unexpanded parameter packs.
13142 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
13143 UPPC_ExceptionType)) {
13144 TInfo = Context.getTrivialTypeSourceInfo(Context.IntTy,
13145 D.getIdentifierLoc());
13149 IdentifierInfo *II = D.getIdentifier();
13150 if (NamedDecl *PrevDecl = LookupSingleName(S, II, D.getIdentifierLoc(),
13151 LookupOrdinaryName,
13152 ForRedeclaration)) {
13153 // The scope should be freshly made just for us. There is just no way
13154 // it contains any previous declaration, except for function parameters in
13155 // a function-try-block's catch statement.
13156 assert(!S->isDeclScope(PrevDecl));
13157 if (isDeclInScope(PrevDecl, CurContext, S)) {
13158 Diag(D.getIdentifierLoc(), diag::err_redefinition)
13159 << D.getIdentifier();
13160 Diag(PrevDecl->getLocation(), diag::note_previous_definition);
13162 } else if (PrevDecl->isTemplateParameter())
13163 // Maybe we will complain about the shadowed template parameter.
13164 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
13167 if (D.getCXXScopeSpec().isSet() && !Invalid) {
13168 Diag(D.getIdentifierLoc(), diag::err_qualified_catch_declarator)
13169 << D.getCXXScopeSpec().getRange();
13173 VarDecl *ExDecl = BuildExceptionDeclaration(S, TInfo,
13175 D.getIdentifierLoc(),
13176 D.getIdentifier());
13178 ExDecl->setInvalidDecl();
13180 // Add the exception declaration into this scope.
13182 PushOnScopeChains(ExDecl, S);
13184 CurContext->addDecl(ExDecl);
13186 ProcessDeclAttributes(S, ExDecl, D);
13190 Decl *Sema::ActOnStaticAssertDeclaration(SourceLocation StaticAssertLoc,
13192 Expr *AssertMessageExpr,
13193 SourceLocation RParenLoc) {
13194 StringLiteral *AssertMessage =
13195 AssertMessageExpr ? cast<StringLiteral>(AssertMessageExpr) : nullptr;
13197 if (DiagnoseUnexpandedParameterPack(AssertExpr, UPPC_StaticAssertExpression))
13200 return BuildStaticAssertDeclaration(StaticAssertLoc, AssertExpr,
13201 AssertMessage, RParenLoc, false);
13204 Decl *Sema::BuildStaticAssertDeclaration(SourceLocation StaticAssertLoc,
13206 StringLiteral *AssertMessage,
13207 SourceLocation RParenLoc,
13209 assert(AssertExpr != nullptr && "Expected non-null condition");
13210 if (!AssertExpr->isTypeDependent() && !AssertExpr->isValueDependent() &&
13212 // In a static_assert-declaration, the constant-expression shall be a
13213 // constant expression that can be contextually converted to bool.
13214 ExprResult Converted = PerformContextuallyConvertToBool(AssertExpr);
13215 if (Converted.isInvalid())
13219 if (!Failed && VerifyIntegerConstantExpression(Converted.get(), &Cond,
13220 diag::err_static_assert_expression_is_not_constant,
13221 /*AllowFold=*/false).isInvalid())
13224 if (!Failed && !Cond) {
13225 SmallString<256> MsgBuffer;
13226 llvm::raw_svector_ostream Msg(MsgBuffer);
13228 AssertMessage->printPretty(Msg, nullptr, getPrintingPolicy());
13229 Diag(StaticAssertLoc, diag::err_static_assert_failed)
13230 << !AssertMessage << Msg.str() << AssertExpr->getSourceRange();
13235 Decl *Decl = StaticAssertDecl::Create(Context, CurContext, StaticAssertLoc,
13236 AssertExpr, AssertMessage, RParenLoc,
13239 CurContext->addDecl(Decl);
13243 /// \brief Perform semantic analysis of the given friend type declaration.
13245 /// \returns A friend declaration that.
13246 FriendDecl *Sema::CheckFriendTypeDecl(SourceLocation LocStart,
13247 SourceLocation FriendLoc,
13248 TypeSourceInfo *TSInfo) {
13249 assert(TSInfo && "NULL TypeSourceInfo for friend type declaration");
13251 QualType T = TSInfo->getType();
13252 SourceRange TypeRange = TSInfo->getTypeLoc().getLocalSourceRange();
13254 // C++03 [class.friend]p2:
13255 // An elaborated-type-specifier shall be used in a friend declaration
13258 // * The class-key of the elaborated-type-specifier is required.
13259 if (!CodeSynthesisContexts.empty()) {
13260 // Do not complain about the form of friend template types during any kind
13261 // of code synthesis. For template instantiation, we will have complained
13262 // when the template was defined.
13264 if (!T->isElaboratedTypeSpecifier()) {
13265 // If we evaluated the type to a record type, suggest putting
13267 if (const RecordType *RT = T->getAs<RecordType>()) {
13268 RecordDecl *RD = RT->getDecl();
13270 SmallString<16> InsertionText(" ");
13271 InsertionText += RD->getKindName();
13273 Diag(TypeRange.getBegin(),
13274 getLangOpts().CPlusPlus11 ?
13275 diag::warn_cxx98_compat_unelaborated_friend_type :
13276 diag::ext_unelaborated_friend_type)
13277 << (unsigned) RD->getTagKind()
13279 << FixItHint::CreateInsertion(getLocForEndOfToken(FriendLoc),
13283 getLangOpts().CPlusPlus11 ?
13284 diag::warn_cxx98_compat_nonclass_type_friend :
13285 diag::ext_nonclass_type_friend)
13289 } else if (T->getAs<EnumType>()) {
13291 getLangOpts().CPlusPlus11 ?
13292 diag::warn_cxx98_compat_enum_friend :
13293 diag::ext_enum_friend)
13298 // C++11 [class.friend]p3:
13299 // A friend declaration that does not declare a function shall have one
13300 // of the following forms:
13301 // friend elaborated-type-specifier ;
13302 // friend simple-type-specifier ;
13303 // friend typename-specifier ;
13304 if (getLangOpts().CPlusPlus11 && LocStart != FriendLoc)
13305 Diag(FriendLoc, diag::err_friend_not_first_in_declaration) << T;
13308 // If the type specifier in a friend declaration designates a (possibly
13309 // cv-qualified) class type, that class is declared as a friend; otherwise,
13310 // the friend declaration is ignored.
13311 return FriendDecl::Create(Context, CurContext,
13312 TSInfo->getTypeLoc().getLocStart(), TSInfo,
13316 /// Handle a friend tag declaration where the scope specifier was
13318 Decl *Sema::ActOnTemplatedFriendTag(Scope *S, SourceLocation FriendLoc,
13319 unsigned TagSpec, SourceLocation TagLoc,
13321 IdentifierInfo *Name,
13322 SourceLocation NameLoc,
13323 AttributeList *Attr,
13324 MultiTemplateParamsArg TempParamLists) {
13325 TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
13327 bool IsMemberSpecialization = false;
13328 bool Invalid = false;
13330 if (TemplateParameterList *TemplateParams =
13331 MatchTemplateParametersToScopeSpecifier(
13332 TagLoc, NameLoc, SS, nullptr, TempParamLists, /*friend*/ true,
13333 IsMemberSpecialization, Invalid)) {
13334 if (TemplateParams->size() > 0) {
13335 // This is a declaration of a class template.
13339 return CheckClassTemplate(S, TagSpec, TUK_Friend, TagLoc, SS, Name,
13340 NameLoc, Attr, TemplateParams, AS_public,
13341 /*ModulePrivateLoc=*/SourceLocation(),
13342 FriendLoc, TempParamLists.size() - 1,
13343 TempParamLists.data()).get();
13345 // The "template<>" header is extraneous.
13346 Diag(TemplateParams->getTemplateLoc(), diag::err_template_tag_noparams)
13347 << TypeWithKeyword::getTagTypeKindName(Kind) << Name;
13348 IsMemberSpecialization = true;
13352 if (Invalid) return nullptr;
13354 bool isAllExplicitSpecializations = true;
13355 for (unsigned I = TempParamLists.size(); I-- > 0; ) {
13356 if (TempParamLists[I]->size()) {
13357 isAllExplicitSpecializations = false;
13362 // FIXME: don't ignore attributes.
13364 // If it's explicit specializations all the way down, just forget
13365 // about the template header and build an appropriate non-templated
13366 // friend. TODO: for source fidelity, remember the headers.
13367 if (isAllExplicitSpecializations) {
13368 if (SS.isEmpty()) {
13369 bool Owned = false;
13370 bool IsDependent = false;
13371 return ActOnTag(S, TagSpec, TUK_Friend, TagLoc, SS, Name, NameLoc,
13373 /*ModulePrivateLoc=*/SourceLocation(),
13374 MultiTemplateParamsArg(), Owned, IsDependent,
13375 /*ScopedEnumKWLoc=*/SourceLocation(),
13376 /*ScopedEnumUsesClassTag=*/false,
13377 /*UnderlyingType=*/TypeResult(),
13378 /*IsTypeSpecifier=*/false);
13381 NestedNameSpecifierLoc QualifierLoc = SS.getWithLocInContext(Context);
13382 ElaboratedTypeKeyword Keyword
13383 = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
13384 QualType T = CheckTypenameType(Keyword, TagLoc, QualifierLoc,
13389 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
13390 if (isa<DependentNameType>(T)) {
13391 DependentNameTypeLoc TL =
13392 TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
13393 TL.setElaboratedKeywordLoc(TagLoc);
13394 TL.setQualifierLoc(QualifierLoc);
13395 TL.setNameLoc(NameLoc);
13397 ElaboratedTypeLoc TL = TSI->getTypeLoc().castAs<ElaboratedTypeLoc>();
13398 TL.setElaboratedKeywordLoc(TagLoc);
13399 TL.setQualifierLoc(QualifierLoc);
13400 TL.getNamedTypeLoc().castAs<TypeSpecTypeLoc>().setNameLoc(NameLoc);
13403 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, NameLoc,
13404 TSI, FriendLoc, TempParamLists);
13405 Friend->setAccess(AS_public);
13406 CurContext->addDecl(Friend);
13410 assert(SS.isNotEmpty() && "valid templated tag with no SS and no direct?");
13414 // Handle the case of a templated-scope friend class. e.g.
13415 // template <class T> class A<T>::B;
13416 // FIXME: we don't support these right now.
13417 Diag(NameLoc, diag::warn_template_qualified_friend_unsupported)
13418 << SS.getScopeRep() << SS.getRange() << cast<CXXRecordDecl>(CurContext);
13419 ElaboratedTypeKeyword ETK = TypeWithKeyword::getKeywordForTagTypeKind(Kind);
13420 QualType T = Context.getDependentNameType(ETK, SS.getScopeRep(), Name);
13421 TypeSourceInfo *TSI = Context.CreateTypeSourceInfo(T);
13422 DependentNameTypeLoc TL = TSI->getTypeLoc().castAs<DependentNameTypeLoc>();
13423 TL.setElaboratedKeywordLoc(TagLoc);
13424 TL.setQualifierLoc(SS.getWithLocInContext(Context));
13425 TL.setNameLoc(NameLoc);
13427 FriendDecl *Friend = FriendDecl::Create(Context, CurContext, NameLoc,
13428 TSI, FriendLoc, TempParamLists);
13429 Friend->setAccess(AS_public);
13430 Friend->setUnsupportedFriend(true);
13431 CurContext->addDecl(Friend);
13436 /// Handle a friend type declaration. This works in tandem with
13439 /// Notes on friend class templates:
13441 /// We generally treat friend class declarations as if they were
13442 /// declaring a class. So, for example, the elaborated type specifier
13443 /// in a friend declaration is required to obey the restrictions of a
13444 /// class-head (i.e. no typedefs in the scope chain), template
13445 /// parameters are required to match up with simple template-ids, &c.
13446 /// However, unlike when declaring a template specialization, it's
13447 /// okay to refer to a template specialization without an empty
13448 /// template parameter declaration, e.g.
13449 /// friend class A<T>::B<unsigned>;
13450 /// We permit this as a special case; if there are any template
13451 /// parameters present at all, require proper matching, i.e.
13452 /// template <> template \<class T> friend class A<int>::B;
13453 Decl *Sema::ActOnFriendTypeDecl(Scope *S, const DeclSpec &DS,
13454 MultiTemplateParamsArg TempParams) {
13455 SourceLocation Loc = DS.getLocStart();
13457 assert(DS.isFriendSpecified());
13458 assert(DS.getStorageClassSpec() == DeclSpec::SCS_unspecified);
13460 // Try to convert the decl specifier to a type. This works for
13461 // friend templates because ActOnTag never produces a ClassTemplateDecl
13462 // for a TUK_Friend.
13463 Declarator TheDeclarator(DS, Declarator::MemberContext);
13464 TypeSourceInfo *TSI = GetTypeForDeclarator(TheDeclarator, S);
13465 QualType T = TSI->getType();
13466 if (TheDeclarator.isInvalidType())
13469 if (DiagnoseUnexpandedParameterPack(Loc, TSI, UPPC_FriendDeclaration))
13472 // This is definitely an error in C++98. It's probably meant to
13473 // be forbidden in C++0x, too, but the specification is just
13476 // The problem is with declarations like the following:
13477 // template <T> friend A<T>::foo;
13478 // where deciding whether a class C is a friend or not now hinges
13479 // on whether there exists an instantiation of A that causes
13480 // 'foo' to equal C. There are restrictions on class-heads
13481 // (which we declare (by fiat) elaborated friend declarations to
13482 // be) that makes this tractable.
13484 // FIXME: handle "template <> friend class A<T>;", which
13485 // is possibly well-formed? Who even knows?
13486 if (TempParams.size() && !T->isElaboratedTypeSpecifier()) {
13487 Diag(Loc, diag::err_tagless_friend_type_template)
13488 << DS.getSourceRange();
13492 // C++98 [class.friend]p1: A friend of a class is a function
13493 // or class that is not a member of the class . . .
13494 // This is fixed in DR77, which just barely didn't make the C++03
13495 // deadline. It's also a very silly restriction that seriously
13496 // affects inner classes and which nobody else seems to implement;
13497 // thus we never diagnose it, not even in -pedantic.
13499 // But note that we could warn about it: it's always useless to
13500 // friend one of your own members (it's not, however, worthless to
13501 // friend a member of an arbitrary specialization of your template).
13504 if (!TempParams.empty())
13505 D = FriendTemplateDecl::Create(Context, CurContext, Loc,
13508 DS.getFriendSpecLoc());
13510 D = CheckFriendTypeDecl(Loc, DS.getFriendSpecLoc(), TSI);
13515 D->setAccess(AS_public);
13516 CurContext->addDecl(D);
13521 NamedDecl *Sema::ActOnFriendFunctionDecl(Scope *S, Declarator &D,
13522 MultiTemplateParamsArg TemplateParams) {
13523 const DeclSpec &DS = D.getDeclSpec();
13525 assert(DS.isFriendSpecified());
13526 assert(DS.getStorageClassSpec() == DeclSpec::SCS_unspecified);
13528 SourceLocation Loc = D.getIdentifierLoc();
13529 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
13531 // C++ [class.friend]p1
13532 // A friend of a class is a function or class....
13533 // Note that this sees through typedefs, which is intended.
13534 // It *doesn't* see through dependent types, which is correct
13535 // according to [temp.arg.type]p3:
13536 // If a declaration acquires a function type through a
13537 // type dependent on a template-parameter and this causes
13538 // a declaration that does not use the syntactic form of a
13539 // function declarator to have a function type, the program
13541 if (!TInfo->getType()->isFunctionType()) {
13542 Diag(Loc, diag::err_unexpected_friend);
13544 // It might be worthwhile to try to recover by creating an
13545 // appropriate declaration.
13549 // C++ [namespace.memdef]p3
13550 // - If a friend declaration in a non-local class first declares a
13551 // class or function, the friend class or function is a member
13552 // of the innermost enclosing namespace.
13553 // - The name of the friend is not found by simple name lookup
13554 // until a matching declaration is provided in that namespace
13555 // scope (either before or after the class declaration granting
13557 // - If a friend function is called, its name may be found by the
13558 // name lookup that considers functions from namespaces and
13559 // classes associated with the types of the function arguments.
13560 // - When looking for a prior declaration of a class or a function
13561 // declared as a friend, scopes outside the innermost enclosing
13562 // namespace scope are not considered.
13564 CXXScopeSpec &SS = D.getCXXScopeSpec();
13565 DeclarationNameInfo NameInfo = GetNameForDeclarator(D);
13566 DeclarationName Name = NameInfo.getName();
13569 // Check for unexpanded parameter packs.
13570 if (DiagnoseUnexpandedParameterPack(Loc, TInfo, UPPC_FriendDeclaration) ||
13571 DiagnoseUnexpandedParameterPack(NameInfo, UPPC_FriendDeclaration) ||
13572 DiagnoseUnexpandedParameterPack(SS, UPPC_FriendDeclaration))
13575 // The context we found the declaration in, or in which we should
13576 // create the declaration.
13578 Scope *DCScope = S;
13579 LookupResult Previous(*this, NameInfo, LookupOrdinaryName,
13582 // There are five cases here.
13583 // - There's no scope specifier and we're in a local class. Only look
13584 // for functions declared in the immediately-enclosing block scope.
13585 // We recover from invalid scope qualifiers as if they just weren't there.
13586 FunctionDecl *FunctionContainingLocalClass = nullptr;
13587 if ((SS.isInvalid() || !SS.isSet()) &&
13588 (FunctionContainingLocalClass =
13589 cast<CXXRecordDecl>(CurContext)->isLocalClass())) {
13590 // C++11 [class.friend]p11:
13591 // If a friend declaration appears in a local class and the name
13592 // specified is an unqualified name, a prior declaration is
13593 // looked up without considering scopes that are outside the
13594 // innermost enclosing non-class scope. For a friend function
13595 // declaration, if there is no prior declaration, the program is
13598 // Find the innermost enclosing non-class scope. This is the block
13599 // scope containing the local class definition (or for a nested class,
13600 // the outer local class).
13601 DCScope = S->getFnParent();
13603 // Look up the function name in the scope.
13604 Previous.clear(LookupLocalFriendName);
13605 LookupName(Previous, S, /*AllowBuiltinCreation*/false);
13607 if (!Previous.empty()) {
13608 // All possible previous declarations must have the same context:
13609 // either they were declared at block scope or they are members of
13610 // one of the enclosing local classes.
13611 DC = Previous.getRepresentativeDecl()->getDeclContext();
13613 // This is ill-formed, but provide the context that we would have
13614 // declared the function in, if we were permitted to, for error recovery.
13615 DC = FunctionContainingLocalClass;
13617 adjustContextForLocalExternDecl(DC);
13619 // C++ [class.friend]p6:
13620 // A function can be defined in a friend declaration of a class if and
13621 // only if the class is a non-local class (9.8), the function name is
13622 // unqualified, and the function has namespace scope.
13623 if (D.isFunctionDefinition()) {
13624 Diag(NameInfo.getBeginLoc(), diag::err_friend_def_in_local_class);
13627 // - There's no scope specifier, in which case we just go to the
13628 // appropriate scope and look for a function or function template
13629 // there as appropriate.
13630 } else if (SS.isInvalid() || !SS.isSet()) {
13631 // C++11 [namespace.memdef]p3:
13632 // If the name in a friend declaration is neither qualified nor
13633 // a template-id and the declaration is a function or an
13634 // elaborated-type-specifier, the lookup to determine whether
13635 // the entity has been previously declared shall not consider
13636 // any scopes outside the innermost enclosing namespace.
13637 bool isTemplateId = D.getName().getKind() == UnqualifiedId::IK_TemplateId;
13639 // Find the appropriate context according to the above.
13642 // Skip class contexts. If someone can cite chapter and verse
13643 // for this behavior, that would be nice --- it's what GCC and
13644 // EDG do, and it seems like a reasonable intent, but the spec
13645 // really only says that checks for unqualified existing
13646 // declarations should stop at the nearest enclosing namespace,
13647 // not that they should only consider the nearest enclosing
13649 while (DC->isRecord())
13650 DC = DC->getParent();
13652 DeclContext *LookupDC = DC;
13653 while (LookupDC->isTransparentContext())
13654 LookupDC = LookupDC->getParent();
13657 LookupQualifiedName(Previous, LookupDC);
13659 if (!Previous.empty()) {
13664 if (isTemplateId) {
13665 if (isa<TranslationUnitDecl>(LookupDC)) break;
13667 if (LookupDC->isFileContext()) break;
13669 LookupDC = LookupDC->getParent();
13672 DCScope = getScopeForDeclContext(S, DC);
13674 // - There's a non-dependent scope specifier, in which case we
13675 // compute it and do a previous lookup there for a function
13676 // or function template.
13677 } else if (!SS.getScopeRep()->isDependent()) {
13678 DC = computeDeclContext(SS);
13679 if (!DC) return nullptr;
13681 if (RequireCompleteDeclContext(SS, DC)) return nullptr;
13683 LookupQualifiedName(Previous, DC);
13685 // Ignore things found implicitly in the wrong scope.
13686 // TODO: better diagnostics for this case. Suggesting the right
13687 // qualified scope would be nice...
13688 LookupResult::Filter F = Previous.makeFilter();
13689 while (F.hasNext()) {
13690 NamedDecl *D = F.next();
13691 if (!DC->InEnclosingNamespaceSetOf(
13692 D->getDeclContext()->getRedeclContext()))
13697 if (Previous.empty()) {
13698 D.setInvalidType();
13699 Diag(Loc, diag::err_qualified_friend_not_found)
13700 << Name << TInfo->getType();
13704 // C++ [class.friend]p1: A friend of a class is a function or
13705 // class that is not a member of the class . . .
13706 if (DC->Equals(CurContext))
13707 Diag(DS.getFriendSpecLoc(),
13708 getLangOpts().CPlusPlus11 ?
13709 diag::warn_cxx98_compat_friend_is_member :
13710 diag::err_friend_is_member);
13712 if (D.isFunctionDefinition()) {
13713 // C++ [class.friend]p6:
13714 // A function can be defined in a friend declaration of a class if and
13715 // only if the class is a non-local class (9.8), the function name is
13716 // unqualified, and the function has namespace scope.
13717 SemaDiagnosticBuilder DB
13718 = Diag(SS.getRange().getBegin(), diag::err_qualified_friend_def);
13720 DB << SS.getScopeRep();
13721 if (DC->isFileContext())
13722 DB << FixItHint::CreateRemoval(SS.getRange());
13726 // - There's a scope specifier that does not match any template
13727 // parameter lists, in which case we use some arbitrary context,
13728 // create a method or method template, and wait for instantiation.
13729 // - There's a scope specifier that does match some template
13730 // parameter lists, which we don't handle right now.
13732 if (D.isFunctionDefinition()) {
13733 // C++ [class.friend]p6:
13734 // A function can be defined in a friend declaration of a class if and
13735 // only if the class is a non-local class (9.8), the function name is
13736 // unqualified, and the function has namespace scope.
13737 Diag(SS.getRange().getBegin(), diag::err_qualified_friend_def)
13738 << SS.getScopeRep();
13742 assert(isa<CXXRecordDecl>(DC) && "friend declaration not in class?");
13745 if (!DC->isRecord()) {
13747 switch (D.getName().getKind()) {
13748 case UnqualifiedId::IK_ConstructorTemplateId:
13749 case UnqualifiedId::IK_ConstructorName:
13752 case UnqualifiedId::IK_DestructorName:
13755 case UnqualifiedId::IK_ConversionFunctionId:
13758 case UnqualifiedId::IK_DeductionGuideName:
13761 case UnqualifiedId::IK_Identifier:
13762 case UnqualifiedId::IK_ImplicitSelfParam:
13763 case UnqualifiedId::IK_LiteralOperatorId:
13764 case UnqualifiedId::IK_OperatorFunctionId:
13765 case UnqualifiedId::IK_TemplateId:
13768 // This implies that it has to be an operator or function.
13769 if (DiagArg >= 0) {
13770 Diag(Loc, diag::err_introducing_special_friend) << DiagArg;
13775 // FIXME: This is an egregious hack to cope with cases where the scope stack
13776 // does not contain the declaration context, i.e., in an out-of-line
13777 // definition of a class.
13778 Scope FakeDCScope(S, Scope::DeclScope, Diags);
13780 FakeDCScope.setEntity(DC);
13781 DCScope = &FakeDCScope;
13784 bool AddToScope = true;
13785 NamedDecl *ND = ActOnFunctionDeclarator(DCScope, D, DC, TInfo, Previous,
13786 TemplateParams, AddToScope);
13787 if (!ND) return nullptr;
13789 assert(ND->getLexicalDeclContext() == CurContext);
13791 // If we performed typo correction, we might have added a scope specifier
13792 // and changed the decl context.
13793 DC = ND->getDeclContext();
13795 // Add the function declaration to the appropriate lookup tables,
13796 // adjusting the redeclarations list as necessary. We don't
13797 // want to do this yet if the friending class is dependent.
13799 // Also update the scope-based lookup if the target context's
13800 // lookup context is in lexical scope.
13801 if (!CurContext->isDependentContext()) {
13802 DC = DC->getRedeclContext();
13803 DC->makeDeclVisibleInContext(ND);
13804 if (Scope *EnclosingScope = getScopeForDeclContext(S, DC))
13805 PushOnScopeChains(ND, EnclosingScope, /*AddToContext=*/ false);
13808 FriendDecl *FrD = FriendDecl::Create(Context, CurContext,
13809 D.getIdentifierLoc(), ND,
13810 DS.getFriendSpecLoc());
13811 FrD->setAccess(AS_public);
13812 CurContext->addDecl(FrD);
13814 if (ND->isInvalidDecl()) {
13815 FrD->setInvalidDecl();
13817 if (DC->isRecord()) CheckFriendAccess(ND);
13820 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
13821 FD = FTD->getTemplatedDecl();
13823 FD = cast<FunctionDecl>(ND);
13825 // C++11 [dcl.fct.default]p4: If a friend declaration specifies a
13826 // default argument expression, that declaration shall be a definition
13827 // and shall be the only declaration of the function or function
13828 // template in the translation unit.
13829 if (functionDeclHasDefaultArgument(FD)) {
13830 // We can't look at FD->getPreviousDecl() because it may not have been set
13831 // if we're in a dependent context. If the function is known to be a
13832 // redeclaration, we will have narrowed Previous down to the right decl.
13833 if (D.isRedeclaration()) {
13834 Diag(FD->getLocation(), diag::err_friend_decl_with_def_arg_redeclared);
13835 Diag(Previous.getRepresentativeDecl()->getLocation(),
13836 diag::note_previous_declaration);
13837 } else if (!D.isFunctionDefinition())
13838 Diag(FD->getLocation(), diag::err_friend_decl_with_def_arg_must_be_def);
13841 // Mark templated-scope function declarations as unsupported.
13842 if (FD->getNumTemplateParameterLists() && SS.isValid()) {
13843 Diag(FD->getLocation(), diag::warn_template_qualified_friend_unsupported)
13844 << SS.getScopeRep() << SS.getRange()
13845 << cast<CXXRecordDecl>(CurContext);
13846 FrD->setUnsupportedFriend(true);
13853 void Sema::SetDeclDeleted(Decl *Dcl, SourceLocation DelLoc) {
13854 AdjustDeclIfTemplate(Dcl);
13856 FunctionDecl *Fn = dyn_cast_or_null<FunctionDecl>(Dcl);
13858 Diag(DelLoc, diag::err_deleted_non_function);
13862 if (const FunctionDecl *Prev = Fn->getPreviousDecl()) {
13863 // Don't consider the implicit declaration we generate for explicit
13864 // specializations. FIXME: Do not generate these implicit declarations.
13865 if ((Prev->getTemplateSpecializationKind() != TSK_ExplicitSpecialization ||
13866 Prev->getPreviousDecl()) &&
13867 !Prev->isDefined()) {
13868 Diag(DelLoc, diag::err_deleted_decl_not_first);
13869 Diag(Prev->getLocation().isInvalid() ? DelLoc : Prev->getLocation(),
13870 Prev->isImplicit() ? diag::note_previous_implicit_declaration
13871 : diag::note_previous_declaration);
13873 // If the declaration wasn't the first, we delete the function anyway for
13875 Fn = Fn->getCanonicalDecl();
13878 // dllimport/dllexport cannot be deleted.
13879 if (const InheritableAttr *DLLAttr = getDLLAttr(Fn)) {
13880 Diag(Fn->getLocation(), diag::err_attribute_dll_deleted) << DLLAttr;
13881 Fn->setInvalidDecl();
13884 if (Fn->isDeleted())
13887 // See if we're deleting a function which is already known to override a
13888 // non-deleted virtual function.
13889 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(Fn)) {
13890 bool IssuedDiagnostic = false;
13891 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(),
13892 E = MD->end_overridden_methods();
13894 if (!(*MD->begin_overridden_methods())->isDeleted()) {
13895 if (!IssuedDiagnostic) {
13896 Diag(DelLoc, diag::err_deleted_override) << MD->getDeclName();
13897 IssuedDiagnostic = true;
13899 Diag((*I)->getLocation(), diag::note_overridden_virtual_function);
13902 // If this function was implicitly deleted because it was defaulted,
13903 // explain why it was deleted.
13904 if (IssuedDiagnostic && MD->isDefaulted())
13905 ShouldDeleteSpecialMember(MD, getSpecialMember(MD), nullptr,
13909 // C++11 [basic.start.main]p3:
13910 // A program that defines main as deleted [...] is ill-formed.
13912 Diag(DelLoc, diag::err_deleted_main);
13914 // C++11 [dcl.fct.def.delete]p4:
13915 // A deleted function is implicitly inline.
13916 Fn->setImplicitlyInline();
13917 Fn->setDeletedAsWritten();
13920 void Sema::SetDeclDefaulted(Decl *Dcl, SourceLocation DefaultLoc) {
13921 CXXMethodDecl *MD = dyn_cast_or_null<CXXMethodDecl>(Dcl);
13924 if (MD->getParent()->isDependentType()) {
13925 MD->setDefaulted();
13926 MD->setExplicitlyDefaulted();
13930 CXXSpecialMember Member = getSpecialMember(MD);
13931 if (Member == CXXInvalid) {
13932 if (!MD->isInvalidDecl())
13933 Diag(DefaultLoc, diag::err_default_special_members);
13937 MD->setDefaulted();
13938 MD->setExplicitlyDefaulted();
13940 // Unset that we will have a body for this function. We might not,
13941 // if it turns out to be trivial, and we don't need this marking now
13942 // that we've marked it as defaulted.
13943 MD->setWillHaveBody(false);
13945 // If this definition appears within the record, do the checking when
13946 // the record is complete.
13947 const FunctionDecl *Primary = MD;
13948 if (const FunctionDecl *Pattern = MD->getTemplateInstantiationPattern())
13949 // Ask the template instantiation pattern that actually had the
13950 // '= default' on it.
13953 // If the method was defaulted on its first declaration, we will have
13954 // already performed the checking in CheckCompletedCXXClass. Such a
13955 // declaration doesn't trigger an implicit definition.
13956 if (Primary->getCanonicalDecl()->isDefaulted())
13959 CheckExplicitlyDefaultedSpecialMember(MD);
13961 if (!MD->isInvalidDecl())
13962 DefineImplicitSpecialMember(*this, MD, DefaultLoc);
13964 Diag(DefaultLoc, diag::err_default_special_members);
13968 static void SearchForReturnInStmt(Sema &Self, Stmt *S) {
13969 for (Stmt *SubStmt : S->children()) {
13972 if (isa<ReturnStmt>(SubStmt))
13973 Self.Diag(SubStmt->getLocStart(),
13974 diag::err_return_in_constructor_handler);
13975 if (!isa<Expr>(SubStmt))
13976 SearchForReturnInStmt(Self, SubStmt);
13980 void Sema::DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock) {
13981 for (unsigned I = 0, E = TryBlock->getNumHandlers(); I != E; ++I) {
13982 CXXCatchStmt *Handler = TryBlock->getHandler(I);
13983 SearchForReturnInStmt(*this, Handler);
13987 bool Sema::CheckOverridingFunctionAttributes(const CXXMethodDecl *New,
13988 const CXXMethodDecl *Old) {
13989 const FunctionType *NewFT = New->getType()->getAs<FunctionType>();
13990 const FunctionType *OldFT = Old->getType()->getAs<FunctionType>();
13992 CallingConv NewCC = NewFT->getCallConv(), OldCC = OldFT->getCallConv();
13994 // If the calling conventions match, everything is fine
13995 if (NewCC == OldCC)
13998 // If the calling conventions mismatch because the new function is static,
13999 // suppress the calling convention mismatch error; the error about static
14000 // function override (err_static_overrides_virtual from
14001 // Sema::CheckFunctionDeclaration) is more clear.
14002 if (New->getStorageClass() == SC_Static)
14005 Diag(New->getLocation(),
14006 diag::err_conflicting_overriding_cc_attributes)
14007 << New->getDeclName() << New->getType() << Old->getType();
14008 Diag(Old->getLocation(), diag::note_overridden_virtual_function);
14012 bool Sema::CheckOverridingFunctionReturnType(const CXXMethodDecl *New,
14013 const CXXMethodDecl *Old) {
14014 QualType NewTy = New->getType()->getAs<FunctionType>()->getReturnType();
14015 QualType OldTy = Old->getType()->getAs<FunctionType>()->getReturnType();
14017 if (Context.hasSameType(NewTy, OldTy) ||
14018 NewTy->isDependentType() || OldTy->isDependentType())
14021 // Check if the return types are covariant
14022 QualType NewClassTy, OldClassTy;
14024 /// Both types must be pointers or references to classes.
14025 if (const PointerType *NewPT = NewTy->getAs<PointerType>()) {
14026 if (const PointerType *OldPT = OldTy->getAs<PointerType>()) {
14027 NewClassTy = NewPT->getPointeeType();
14028 OldClassTy = OldPT->getPointeeType();
14030 } else if (const ReferenceType *NewRT = NewTy->getAs<ReferenceType>()) {
14031 if (const ReferenceType *OldRT = OldTy->getAs<ReferenceType>()) {
14032 if (NewRT->getTypeClass() == OldRT->getTypeClass()) {
14033 NewClassTy = NewRT->getPointeeType();
14034 OldClassTy = OldRT->getPointeeType();
14039 // The return types aren't either both pointers or references to a class type.
14040 if (NewClassTy.isNull()) {
14041 Diag(New->getLocation(),
14042 diag::err_different_return_type_for_overriding_virtual_function)
14043 << New->getDeclName() << NewTy << OldTy
14044 << New->getReturnTypeSourceRange();
14045 Diag(Old->getLocation(), diag::note_overridden_virtual_function)
14046 << Old->getReturnTypeSourceRange();
14051 if (!Context.hasSameUnqualifiedType(NewClassTy, OldClassTy)) {
14052 // C++14 [class.virtual]p8:
14053 // If the class type in the covariant return type of D::f differs from
14054 // that of B::f, the class type in the return type of D::f shall be
14055 // complete at the point of declaration of D::f or shall be the class
14057 if (const RecordType *RT = NewClassTy->getAs<RecordType>()) {
14058 if (!RT->isBeingDefined() &&
14059 RequireCompleteType(New->getLocation(), NewClassTy,
14060 diag::err_covariant_return_incomplete,
14061 New->getDeclName()))
14065 // Check if the new class derives from the old class.
14066 if (!IsDerivedFrom(New->getLocation(), NewClassTy, OldClassTy)) {
14067 Diag(New->getLocation(), diag::err_covariant_return_not_derived)
14068 << New->getDeclName() << NewTy << OldTy
14069 << New->getReturnTypeSourceRange();
14070 Diag(Old->getLocation(), diag::note_overridden_virtual_function)
14071 << Old->getReturnTypeSourceRange();
14075 // Check if we the conversion from derived to base is valid.
14076 if (CheckDerivedToBaseConversion(
14077 NewClassTy, OldClassTy,
14078 diag::err_covariant_return_inaccessible_base,
14079 diag::err_covariant_return_ambiguous_derived_to_base_conv,
14080 New->getLocation(), New->getReturnTypeSourceRange(),
14081 New->getDeclName(), nullptr)) {
14082 // FIXME: this note won't trigger for delayed access control
14083 // diagnostics, and it's impossible to get an undelayed error
14084 // here from access control during the original parse because
14085 // the ParsingDeclSpec/ParsingDeclarator are still in scope.
14086 Diag(Old->getLocation(), diag::note_overridden_virtual_function)
14087 << Old->getReturnTypeSourceRange();
14092 // The qualifiers of the return types must be the same.
14093 if (NewTy.getLocalCVRQualifiers() != OldTy.getLocalCVRQualifiers()) {
14094 Diag(New->getLocation(),
14095 diag::err_covariant_return_type_different_qualifications)
14096 << New->getDeclName() << NewTy << OldTy
14097 << New->getReturnTypeSourceRange();
14098 Diag(Old->getLocation(), diag::note_overridden_virtual_function)
14099 << Old->getReturnTypeSourceRange();
14104 // The new class type must have the same or less qualifiers as the old type.
14105 if (NewClassTy.isMoreQualifiedThan(OldClassTy)) {
14106 Diag(New->getLocation(),
14107 diag::err_covariant_return_type_class_type_more_qualified)
14108 << New->getDeclName() << NewTy << OldTy
14109 << New->getReturnTypeSourceRange();
14110 Diag(Old->getLocation(), diag::note_overridden_virtual_function)
14111 << Old->getReturnTypeSourceRange();
14118 /// \brief Mark the given method pure.
14120 /// \param Method the method to be marked pure.
14122 /// \param InitRange the source range that covers the "0" initializer.
14123 bool Sema::CheckPureMethod(CXXMethodDecl *Method, SourceRange InitRange) {
14124 SourceLocation EndLoc = InitRange.getEnd();
14125 if (EndLoc.isValid())
14126 Method->setRangeEnd(EndLoc);
14128 if (Method->isVirtual() || Method->getParent()->isDependentContext()) {
14133 if (!Method->isInvalidDecl())
14134 Diag(Method->getLocation(), diag::err_non_virtual_pure)
14135 << Method->getDeclName() << InitRange;
14139 void Sema::ActOnPureSpecifier(Decl *D, SourceLocation ZeroLoc) {
14140 if (D->getFriendObjectKind())
14141 Diag(D->getLocation(), diag::err_pure_friend);
14142 else if (auto *M = dyn_cast<CXXMethodDecl>(D))
14143 CheckPureMethod(M, ZeroLoc);
14145 Diag(D->getLocation(), diag::err_illegal_initializer);
14148 /// \brief Determine whether the given declaration is a static data member.
14149 static bool isStaticDataMember(const Decl *D) {
14150 if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(D))
14151 return Var->isStaticDataMember();
14156 /// ActOnCXXEnterDeclInitializer - Invoked when we are about to parse
14157 /// an initializer for the out-of-line declaration 'Dcl'. The scope
14158 /// is a fresh scope pushed for just this purpose.
14160 /// After this method is called, according to [C++ 3.4.1p13], if 'Dcl' is a
14161 /// static data member of class X, names should be looked up in the scope of
14163 void Sema::ActOnCXXEnterDeclInitializer(Scope *S, Decl *D) {
14164 // If there is no declaration, there was an error parsing it.
14165 if (!D || D->isInvalidDecl())
14168 // We will always have a nested name specifier here, but this declaration
14169 // might not be out of line if the specifier names the current namespace:
14172 if (D->isOutOfLine())
14173 EnterDeclaratorContext(S, D->getDeclContext());
14175 // If we are parsing the initializer for a static data member, push a
14176 // new expression evaluation context that is associated with this static
14178 if (isStaticDataMember(D))
14179 PushExpressionEvaluationContext(
14180 ExpressionEvaluationContext::PotentiallyEvaluated, D);
14183 /// ActOnCXXExitDeclInitializer - Invoked after we are finished parsing an
14184 /// initializer for the out-of-line declaration 'D'.
14185 void Sema::ActOnCXXExitDeclInitializer(Scope *S, Decl *D) {
14186 // If there is no declaration, there was an error parsing it.
14187 if (!D || D->isInvalidDecl())
14190 if (isStaticDataMember(D))
14191 PopExpressionEvaluationContext();
14193 if (D->isOutOfLine())
14194 ExitDeclaratorContext(S);
14197 /// ActOnCXXConditionDeclarationExpr - Parsed a condition declaration of a
14198 /// C++ if/switch/while/for statement.
14199 /// e.g: "if (int x = f()) {...}"
14200 DeclResult Sema::ActOnCXXConditionDeclaration(Scope *S, Declarator &D) {
14202 // The declarator shall not specify a function or an array.
14203 // The type-specifier-seq shall not contain typedef and shall not declare a
14204 // new class or enumeration.
14205 assert(D.getDeclSpec().getStorageClassSpec() != DeclSpec::SCS_typedef &&
14206 "Parser allowed 'typedef' as storage class of condition decl.");
14208 Decl *Dcl = ActOnDeclarator(S, D);
14212 if (isa<FunctionDecl>(Dcl)) { // The declarator shall not specify a function.
14213 Diag(Dcl->getLocation(), diag::err_invalid_use_of_function_type)
14214 << D.getSourceRange();
14221 void Sema::LoadExternalVTableUses() {
14222 if (!ExternalSource)
14225 SmallVector<ExternalVTableUse, 4> VTables;
14226 ExternalSource->ReadUsedVTables(VTables);
14227 SmallVector<VTableUse, 4> NewUses;
14228 for (unsigned I = 0, N = VTables.size(); I != N; ++I) {
14229 llvm::DenseMap<CXXRecordDecl *, bool>::iterator Pos
14230 = VTablesUsed.find(VTables[I].Record);
14231 // Even if a definition wasn't required before, it may be required now.
14232 if (Pos != VTablesUsed.end()) {
14233 if (!Pos->second && VTables[I].DefinitionRequired)
14234 Pos->second = true;
14238 VTablesUsed[VTables[I].Record] = VTables[I].DefinitionRequired;
14239 NewUses.push_back(VTableUse(VTables[I].Record, VTables[I].Location));
14242 VTableUses.insert(VTableUses.begin(), NewUses.begin(), NewUses.end());
14245 void Sema::MarkVTableUsed(SourceLocation Loc, CXXRecordDecl *Class,
14246 bool DefinitionRequired) {
14247 // Ignore any vtable uses in unevaluated operands or for classes that do
14248 // not have a vtable.
14249 if (!Class->isDynamicClass() || Class->isDependentContext() ||
14250 CurContext->isDependentContext() || isUnevaluatedContext())
14253 // Try to insert this class into the map.
14254 LoadExternalVTableUses();
14255 Class = cast<CXXRecordDecl>(Class->getCanonicalDecl());
14256 std::pair<llvm::DenseMap<CXXRecordDecl *, bool>::iterator, bool>
14257 Pos = VTablesUsed.insert(std::make_pair(Class, DefinitionRequired));
14259 // If we already had an entry, check to see if we are promoting this vtable
14260 // to require a definition. If so, we need to reappend to the VTableUses
14261 // list, since we may have already processed the first entry.
14262 if (DefinitionRequired && !Pos.first->second) {
14263 Pos.first->second = true;
14265 // Otherwise, we can early exit.
14269 // The Microsoft ABI requires that we perform the destructor body
14270 // checks (i.e. operator delete() lookup) when the vtable is marked used, as
14271 // the deleting destructor is emitted with the vtable, not with the
14272 // destructor definition as in the Itanium ABI.
14273 if (Context.getTargetInfo().getCXXABI().isMicrosoft()) {
14274 CXXDestructorDecl *DD = Class->getDestructor();
14275 if (DD && DD->isVirtual() && !DD->isDeleted()) {
14276 if (Class->hasUserDeclaredDestructor() && !DD->isDefined()) {
14277 // If this is an out-of-line declaration, marking it referenced will
14278 // not do anything. Manually call CheckDestructor to look up operator
14280 ContextRAII SavedContext(*this, DD);
14281 CheckDestructor(DD);
14283 MarkFunctionReferenced(Loc, Class->getDestructor());
14289 // Local classes need to have their virtual members marked
14290 // immediately. For all other classes, we mark their virtual members
14291 // at the end of the translation unit.
14292 if (Class->isLocalClass())
14293 MarkVirtualMembersReferenced(Loc, Class);
14295 VTableUses.push_back(std::make_pair(Class, Loc));
14298 bool Sema::DefineUsedVTables() {
14299 LoadExternalVTableUses();
14300 if (VTableUses.empty())
14303 // Note: The VTableUses vector could grow as a result of marking
14304 // the members of a class as "used", so we check the size each
14305 // time through the loop and prefer indices (which are stable) to
14306 // iterators (which are not).
14307 bool DefinedAnything = false;
14308 for (unsigned I = 0; I != VTableUses.size(); ++I) {
14309 CXXRecordDecl *Class = VTableUses[I].first->getDefinition();
14312 TemplateSpecializationKind ClassTSK =
14313 Class->getTemplateSpecializationKind();
14315 SourceLocation Loc = VTableUses[I].second;
14317 bool DefineVTable = true;
14319 // If this class has a key function, but that key function is
14320 // defined in another translation unit, we don't need to emit the
14321 // vtable even though we're using it.
14322 const CXXMethodDecl *KeyFunction = Context.getCurrentKeyFunction(Class);
14323 if (KeyFunction && !KeyFunction->hasBody()) {
14324 // The key function is in another translation unit.
14325 DefineVTable = false;
14326 TemplateSpecializationKind TSK =
14327 KeyFunction->getTemplateSpecializationKind();
14328 assert(TSK != TSK_ExplicitInstantiationDefinition &&
14329 TSK != TSK_ImplicitInstantiation &&
14330 "Instantiations don't have key functions");
14332 } else if (!KeyFunction) {
14333 // If we have a class with no key function that is the subject
14334 // of an explicit instantiation declaration, suppress the
14335 // vtable; it will live with the explicit instantiation
14337 bool IsExplicitInstantiationDeclaration =
14338 ClassTSK == TSK_ExplicitInstantiationDeclaration;
14339 for (auto R : Class->redecls()) {
14340 TemplateSpecializationKind TSK
14341 = cast<CXXRecordDecl>(R)->getTemplateSpecializationKind();
14342 if (TSK == TSK_ExplicitInstantiationDeclaration)
14343 IsExplicitInstantiationDeclaration = true;
14344 else if (TSK == TSK_ExplicitInstantiationDefinition) {
14345 IsExplicitInstantiationDeclaration = false;
14350 if (IsExplicitInstantiationDeclaration)
14351 DefineVTable = false;
14354 // The exception specifications for all virtual members may be needed even
14355 // if we are not providing an authoritative form of the vtable in this TU.
14356 // We may choose to emit it available_externally anyway.
14357 if (!DefineVTable) {
14358 MarkVirtualMemberExceptionSpecsNeeded(Loc, Class);
14362 // Mark all of the virtual members of this class as referenced, so
14363 // that we can build a vtable. Then, tell the AST consumer that a
14364 // vtable for this class is required.
14365 DefinedAnything = true;
14366 MarkVirtualMembersReferenced(Loc, Class);
14367 CXXRecordDecl *Canonical = cast<CXXRecordDecl>(Class->getCanonicalDecl());
14368 if (VTablesUsed[Canonical])
14369 Consumer.HandleVTable(Class);
14371 // Warn if we're emitting a weak vtable. The vtable will be weak if there is
14372 // no key function or the key function is inlined. Don't warn in C++ ABIs
14373 // that lack key functions, since the user won't be able to make one.
14374 if (Context.getTargetInfo().getCXXABI().hasKeyFunctions() &&
14375 Class->isExternallyVisible() && ClassTSK != TSK_ImplicitInstantiation) {
14376 const FunctionDecl *KeyFunctionDef = nullptr;
14377 if (!KeyFunction || (KeyFunction->hasBody(KeyFunctionDef) &&
14378 KeyFunctionDef->isInlined())) {
14379 Diag(Class->getLocation(),
14380 ClassTSK == TSK_ExplicitInstantiationDefinition
14381 ? diag::warn_weak_template_vtable
14382 : diag::warn_weak_vtable)
14387 VTableUses.clear();
14389 return DefinedAnything;
14392 void Sema::MarkVirtualMemberExceptionSpecsNeeded(SourceLocation Loc,
14393 const CXXRecordDecl *RD) {
14394 for (const auto *I : RD->methods())
14395 if (I->isVirtual() && !I->isPure())
14396 ResolveExceptionSpec(Loc, I->getType()->castAs<FunctionProtoType>());
14399 void Sema::MarkVirtualMembersReferenced(SourceLocation Loc,
14400 const CXXRecordDecl *RD) {
14401 // Mark all functions which will appear in RD's vtable as used.
14402 CXXFinalOverriderMap FinalOverriders;
14403 RD->getFinalOverriders(FinalOverriders);
14404 for (CXXFinalOverriderMap::const_iterator I = FinalOverriders.begin(),
14405 E = FinalOverriders.end();
14407 for (OverridingMethods::const_iterator OI = I->second.begin(),
14408 OE = I->second.end();
14410 assert(OI->second.size() > 0 && "no final overrider");
14411 CXXMethodDecl *Overrider = OI->second.front().Method;
14413 // C++ [basic.def.odr]p2:
14414 // [...] A virtual member function is used if it is not pure. [...]
14415 if (!Overrider->isPure())
14416 MarkFunctionReferenced(Loc, Overrider);
14420 // Only classes that have virtual bases need a VTT.
14421 if (RD->getNumVBases() == 0)
14424 for (const auto &I : RD->bases()) {
14425 const CXXRecordDecl *Base =
14426 cast<CXXRecordDecl>(I.getType()->getAs<RecordType>()->getDecl());
14427 if (Base->getNumVBases() == 0)
14429 MarkVirtualMembersReferenced(Loc, Base);
14433 /// SetIvarInitializers - This routine builds initialization ASTs for the
14434 /// Objective-C implementation whose ivars need be initialized.
14435 void Sema::SetIvarInitializers(ObjCImplementationDecl *ObjCImplementation) {
14436 if (!getLangOpts().CPlusPlus)
14438 if (ObjCInterfaceDecl *OID = ObjCImplementation->getClassInterface()) {
14439 SmallVector<ObjCIvarDecl*, 8> ivars;
14440 CollectIvarsToConstructOrDestruct(OID, ivars);
14443 SmallVector<CXXCtorInitializer*, 32> AllToInit;
14444 for (unsigned i = 0; i < ivars.size(); i++) {
14445 FieldDecl *Field = ivars[i];
14446 if (Field->isInvalidDecl())
14449 CXXCtorInitializer *Member;
14450 InitializedEntity InitEntity = InitializedEntity::InitializeMember(Field);
14451 InitializationKind InitKind =
14452 InitializationKind::CreateDefault(ObjCImplementation->getLocation());
14454 InitializationSequence InitSeq(*this, InitEntity, InitKind, None);
14455 ExprResult MemberInit =
14456 InitSeq.Perform(*this, InitEntity, InitKind, None);
14457 MemberInit = MaybeCreateExprWithCleanups(MemberInit);
14458 // Note, MemberInit could actually come back empty if no initialization
14459 // is required (e.g., because it would call a trivial default constructor)
14460 if (!MemberInit.get() || MemberInit.isInvalid())
14464 new (Context) CXXCtorInitializer(Context, Field, SourceLocation(),
14466 MemberInit.getAs<Expr>(),
14468 AllToInit.push_back(Member);
14470 // Be sure that the destructor is accessible and is marked as referenced.
14471 if (const RecordType *RecordTy =
14472 Context.getBaseElementType(Field->getType())
14473 ->getAs<RecordType>()) {
14474 CXXRecordDecl *RD = cast<CXXRecordDecl>(RecordTy->getDecl());
14475 if (CXXDestructorDecl *Destructor = LookupDestructor(RD)) {
14476 MarkFunctionReferenced(Field->getLocation(), Destructor);
14477 CheckDestructorAccess(Field->getLocation(), Destructor,
14478 PDiag(diag::err_access_dtor_ivar)
14479 << Context.getBaseElementType(Field->getType()));
14483 ObjCImplementation->setIvarInitializers(Context,
14484 AllToInit.data(), AllToInit.size());
14489 void DelegatingCycleHelper(CXXConstructorDecl* Ctor,
14490 llvm::SmallSet<CXXConstructorDecl*, 4> &Valid,
14491 llvm::SmallSet<CXXConstructorDecl*, 4> &Invalid,
14492 llvm::SmallSet<CXXConstructorDecl*, 4> &Current,
14494 if (Ctor->isInvalidDecl())
14497 CXXConstructorDecl *Target = Ctor->getTargetConstructor();
14499 // Target may not be determinable yet, for instance if this is a dependent
14500 // call in an uninstantiated template.
14502 const FunctionDecl *FNTarget = nullptr;
14503 (void)Target->hasBody(FNTarget);
14504 Target = const_cast<CXXConstructorDecl*>(
14505 cast_or_null<CXXConstructorDecl>(FNTarget));
14508 CXXConstructorDecl *Canonical = Ctor->getCanonicalDecl(),
14509 // Avoid dereferencing a null pointer here.
14510 *TCanonical = Target? Target->getCanonicalDecl() : nullptr;
14512 if (!Current.insert(Canonical).second)
14515 // We know that beyond here, we aren't chaining into a cycle.
14516 if (!Target || !Target->isDelegatingConstructor() ||
14517 Target->isInvalidDecl() || Valid.count(TCanonical)) {
14518 Valid.insert(Current.begin(), Current.end());
14520 // We've hit a cycle.
14521 } else if (TCanonical == Canonical || Invalid.count(TCanonical) ||
14522 Current.count(TCanonical)) {
14523 // If we haven't diagnosed this cycle yet, do so now.
14524 if (!Invalid.count(TCanonical)) {
14525 S.Diag((*Ctor->init_begin())->getSourceLocation(),
14526 diag::warn_delegating_ctor_cycle)
14529 // Don't add a note for a function delegating directly to itself.
14530 if (TCanonical != Canonical)
14531 S.Diag(Target->getLocation(), diag::note_it_delegates_to);
14533 CXXConstructorDecl *C = Target;
14534 while (C->getCanonicalDecl() != Canonical) {
14535 const FunctionDecl *FNTarget = nullptr;
14536 (void)C->getTargetConstructor()->hasBody(FNTarget);
14537 assert(FNTarget && "Ctor cycle through bodiless function");
14539 C = const_cast<CXXConstructorDecl*>(
14540 cast<CXXConstructorDecl>(FNTarget));
14541 S.Diag(C->getLocation(), diag::note_which_delegates_to);
14545 Invalid.insert(Current.begin(), Current.end());
14548 DelegatingCycleHelper(Target, Valid, Invalid, Current, S);
14553 void Sema::CheckDelegatingCtorCycles() {
14554 llvm::SmallSet<CXXConstructorDecl*, 4> Valid, Invalid, Current;
14556 for (DelegatingCtorDeclsType::iterator
14557 I = DelegatingCtorDecls.begin(ExternalSource),
14558 E = DelegatingCtorDecls.end();
14560 DelegatingCycleHelper(*I, Valid, Invalid, Current, *this);
14562 for (llvm::SmallSet<CXXConstructorDecl *, 4>::iterator CI = Invalid.begin(),
14563 CE = Invalid.end();
14565 (*CI)->setInvalidDecl();
14569 /// \brief AST visitor that finds references to the 'this' expression.
14570 class FindCXXThisExpr : public RecursiveASTVisitor<FindCXXThisExpr> {
14574 explicit FindCXXThisExpr(Sema &S) : S(S) { }
14576 bool VisitCXXThisExpr(CXXThisExpr *E) {
14577 S.Diag(E->getLocation(), diag::err_this_static_member_func)
14578 << E->isImplicit();
14584 bool Sema::checkThisInStaticMemberFunctionType(CXXMethodDecl *Method) {
14585 TypeSourceInfo *TSInfo = Method->getTypeSourceInfo();
14589 TypeLoc TL = TSInfo->getTypeLoc();
14590 FunctionProtoTypeLoc ProtoTL = TL.getAs<FunctionProtoTypeLoc>();
14594 // C++11 [expr.prim.general]p3:
14595 // [The expression this] shall not appear before the optional
14596 // cv-qualifier-seq and it shall not appear within the declaration of a
14597 // static member function (although its type and value category are defined
14598 // within a static member function as they are within a non-static member
14599 // function). [ Note: this is because declaration matching does not occur
14600 // until the complete declarator is known. - end note ]
14601 const FunctionProtoType *Proto = ProtoTL.getTypePtr();
14602 FindCXXThisExpr Finder(*this);
14604 // If the return type came after the cv-qualifier-seq, check it now.
14605 if (Proto->hasTrailingReturn() &&
14606 !Finder.TraverseTypeLoc(ProtoTL.getReturnLoc()))
14609 // Check the exception specification.
14610 if (checkThisInStaticMemberFunctionExceptionSpec(Method))
14613 return checkThisInStaticMemberFunctionAttributes(Method);
14616 bool Sema::checkThisInStaticMemberFunctionExceptionSpec(CXXMethodDecl *Method) {
14617 TypeSourceInfo *TSInfo = Method->getTypeSourceInfo();
14621 TypeLoc TL = TSInfo->getTypeLoc();
14622 FunctionProtoTypeLoc ProtoTL = TL.getAs<FunctionProtoTypeLoc>();
14626 const FunctionProtoType *Proto = ProtoTL.getTypePtr();
14627 FindCXXThisExpr Finder(*this);
14629 switch (Proto->getExceptionSpecType()) {
14631 case EST_Uninstantiated:
14632 case EST_Unevaluated:
14633 case EST_BasicNoexcept:
14634 case EST_DynamicNone:
14639 case EST_ComputedNoexcept:
14640 if (!Finder.TraverseStmt(Proto->getNoexceptExpr()))
14644 for (const auto &E : Proto->exceptions()) {
14645 if (!Finder.TraverseType(E))
14654 bool Sema::checkThisInStaticMemberFunctionAttributes(CXXMethodDecl *Method) {
14655 FindCXXThisExpr Finder(*this);
14657 // Check attributes.
14658 for (const auto *A : Method->attrs()) {
14659 // FIXME: This should be emitted by tblgen.
14660 Expr *Arg = nullptr;
14661 ArrayRef<Expr *> Args;
14662 if (const auto *G = dyn_cast<GuardedByAttr>(A))
14664 else if (const auto *G = dyn_cast<PtGuardedByAttr>(A))
14666 else if (const auto *AA = dyn_cast<AcquiredAfterAttr>(A))
14667 Args = llvm::makeArrayRef(AA->args_begin(), AA->args_size());
14668 else if (const auto *AB = dyn_cast<AcquiredBeforeAttr>(A))
14669 Args = llvm::makeArrayRef(AB->args_begin(), AB->args_size());
14670 else if (const auto *ETLF = dyn_cast<ExclusiveTrylockFunctionAttr>(A)) {
14671 Arg = ETLF->getSuccessValue();
14672 Args = llvm::makeArrayRef(ETLF->args_begin(), ETLF->args_size());
14673 } else if (const auto *STLF = dyn_cast<SharedTrylockFunctionAttr>(A)) {
14674 Arg = STLF->getSuccessValue();
14675 Args = llvm::makeArrayRef(STLF->args_begin(), STLF->args_size());
14676 } else if (const auto *LR = dyn_cast<LockReturnedAttr>(A))
14677 Arg = LR->getArg();
14678 else if (const auto *LE = dyn_cast<LocksExcludedAttr>(A))
14679 Args = llvm::makeArrayRef(LE->args_begin(), LE->args_size());
14680 else if (const auto *RC = dyn_cast<RequiresCapabilityAttr>(A))
14681 Args = llvm::makeArrayRef(RC->args_begin(), RC->args_size());
14682 else if (const auto *AC = dyn_cast<AcquireCapabilityAttr>(A))
14683 Args = llvm::makeArrayRef(AC->args_begin(), AC->args_size());
14684 else if (const auto *AC = dyn_cast<TryAcquireCapabilityAttr>(A))
14685 Args = llvm::makeArrayRef(AC->args_begin(), AC->args_size());
14686 else if (const auto *RC = dyn_cast<ReleaseCapabilityAttr>(A))
14687 Args = llvm::makeArrayRef(RC->args_begin(), RC->args_size());
14689 if (Arg && !Finder.TraverseStmt(Arg))
14692 for (unsigned I = 0, N = Args.size(); I != N; ++I) {
14693 if (!Finder.TraverseStmt(Args[I]))
14701 void Sema::checkExceptionSpecification(
14702 bool IsTopLevel, ExceptionSpecificationType EST,
14703 ArrayRef<ParsedType> DynamicExceptions,
14704 ArrayRef<SourceRange> DynamicExceptionRanges, Expr *NoexceptExpr,
14705 SmallVectorImpl<QualType> &Exceptions,
14706 FunctionProtoType::ExceptionSpecInfo &ESI) {
14707 Exceptions.clear();
14709 if (EST == EST_Dynamic) {
14710 Exceptions.reserve(DynamicExceptions.size());
14711 for (unsigned ei = 0, ee = DynamicExceptions.size(); ei != ee; ++ei) {
14712 // FIXME: Preserve type source info.
14713 QualType ET = GetTypeFromParser(DynamicExceptions[ei]);
14716 SmallVector<UnexpandedParameterPack, 2> Unexpanded;
14717 collectUnexpandedParameterPacks(ET, Unexpanded);
14718 if (!Unexpanded.empty()) {
14719 DiagnoseUnexpandedParameterPacks(
14720 DynamicExceptionRanges[ei].getBegin(), UPPC_ExceptionType,
14726 // Check that the type is valid for an exception spec, and
14728 if (!CheckSpecifiedExceptionType(ET, DynamicExceptionRanges[ei]))
14729 Exceptions.push_back(ET);
14731 ESI.Exceptions = Exceptions;
14735 if (EST == EST_ComputedNoexcept) {
14736 // If an error occurred, there's no expression here.
14737 if (NoexceptExpr) {
14738 assert((NoexceptExpr->isTypeDependent() ||
14739 NoexceptExpr->getType()->getCanonicalTypeUnqualified() ==
14741 "Parser should have made sure that the expression is boolean");
14742 if (IsTopLevel && NoexceptExpr &&
14743 DiagnoseUnexpandedParameterPack(NoexceptExpr)) {
14744 ESI.Type = EST_BasicNoexcept;
14748 if (!NoexceptExpr->isValueDependent())
14749 NoexceptExpr = VerifyIntegerConstantExpression(NoexceptExpr, nullptr,
14750 diag::err_noexcept_needs_constant_expression,
14751 /*AllowFold*/ false).get();
14752 ESI.NoexceptExpr = NoexceptExpr;
14758 void Sema::actOnDelayedExceptionSpecification(Decl *MethodD,
14759 ExceptionSpecificationType EST,
14760 SourceRange SpecificationRange,
14761 ArrayRef<ParsedType> DynamicExceptions,
14762 ArrayRef<SourceRange> DynamicExceptionRanges,
14763 Expr *NoexceptExpr) {
14767 // Dig out the method we're referring to.
14768 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(MethodD))
14769 MethodD = FunTmpl->getTemplatedDecl();
14771 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(MethodD);
14775 // Check the exception specification.
14776 llvm::SmallVector<QualType, 4> Exceptions;
14777 FunctionProtoType::ExceptionSpecInfo ESI;
14778 checkExceptionSpecification(/*IsTopLevel*/true, EST, DynamicExceptions,
14779 DynamicExceptionRanges, NoexceptExpr, Exceptions,
14782 // Update the exception specification on the function type.
14783 Context.adjustExceptionSpec(Method, ESI, /*AsWritten*/true);
14785 if (Method->isStatic())
14786 checkThisInStaticMemberFunctionExceptionSpec(Method);
14788 if (Method->isVirtual()) {
14789 // Check overrides, which we previously had to delay.
14790 for (CXXMethodDecl::method_iterator O = Method->begin_overridden_methods(),
14791 OEnd = Method->end_overridden_methods();
14793 CheckOverridingFunctionExceptionSpec(Method, *O);
14797 /// HandleMSProperty - Analyze a __delcspec(property) field of a C++ class.
14799 MSPropertyDecl *Sema::HandleMSProperty(Scope *S, RecordDecl *Record,
14800 SourceLocation DeclStart,
14801 Declarator &D, Expr *BitWidth,
14802 InClassInitStyle InitStyle,
14803 AccessSpecifier AS,
14804 AttributeList *MSPropertyAttr) {
14805 IdentifierInfo *II = D.getIdentifier();
14807 Diag(DeclStart, diag::err_anonymous_property);
14810 SourceLocation Loc = D.getIdentifierLoc();
14812 TypeSourceInfo *TInfo = GetTypeForDeclarator(D, S);
14813 QualType T = TInfo->getType();
14814 if (getLangOpts().CPlusPlus) {
14815 CheckExtraCXXDefaultArguments(D);
14817 if (DiagnoseUnexpandedParameterPack(D.getIdentifierLoc(), TInfo,
14818 UPPC_DataMemberType)) {
14819 D.setInvalidType();
14821 TInfo = Context.getTrivialTypeSourceInfo(T, Loc);
14825 DiagnoseFunctionSpecifiers(D.getDeclSpec());
14827 if (D.getDeclSpec().isInlineSpecified())
14828 Diag(D.getDeclSpec().getInlineSpecLoc(), diag::err_inline_non_function)
14829 << getLangOpts().CPlusPlus1z;
14830 if (DeclSpec::TSCS TSCS = D.getDeclSpec().getThreadStorageClassSpec())
14831 Diag(D.getDeclSpec().getThreadStorageClassSpecLoc(),
14832 diag::err_invalid_thread)
14833 << DeclSpec::getSpecifierName(TSCS);
14835 // Check to see if this name was declared as a member previously
14836 NamedDecl *PrevDecl = nullptr;
14837 LookupResult Previous(*this, II, Loc, LookupMemberName, ForRedeclaration);
14838 LookupName(Previous, S);
14839 switch (Previous.getResultKind()) {
14840 case LookupResult::Found:
14841 case LookupResult::FoundUnresolvedValue:
14842 PrevDecl = Previous.getAsSingle<NamedDecl>();
14845 case LookupResult::FoundOverloaded:
14846 PrevDecl = Previous.getRepresentativeDecl();
14849 case LookupResult::NotFound:
14850 case LookupResult::NotFoundInCurrentInstantiation:
14851 case LookupResult::Ambiguous:
14855 if (PrevDecl && PrevDecl->isTemplateParameter()) {
14856 // Maybe we will complain about the shadowed template parameter.
14857 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl);
14858 // Just pretend that we didn't see the previous declaration.
14859 PrevDecl = nullptr;
14862 if (PrevDecl && !isDeclInScope(PrevDecl, Record, S))
14863 PrevDecl = nullptr;
14865 SourceLocation TSSL = D.getLocStart();
14866 const AttributeList::PropertyData &Data = MSPropertyAttr->getPropertyData();
14867 MSPropertyDecl *NewPD = MSPropertyDecl::Create(
14868 Context, Record, Loc, II, T, TInfo, TSSL, Data.GetterId, Data.SetterId);
14869 ProcessDeclAttributes(TUScope, NewPD, D);
14870 NewPD->setAccess(AS);
14872 if (NewPD->isInvalidDecl())
14873 Record->setInvalidDecl();
14875 if (D.getDeclSpec().isModulePrivateSpecified())
14876 NewPD->setModulePrivate();
14878 if (NewPD->isInvalidDecl() && PrevDecl) {
14879 // Don't introduce NewFD into scope; there's already something
14880 // with the same name in the same scope.
14882 PushOnScopeChains(NewPD, S);
14884 Record->addDecl(NewPD);