SemaDeclCXX.cpp revision 6865480f0ccf049ef53bd1e058aaacc4f77beebe
1//===------ SemaDeclCXX.cpp - Semantic Analysis for C++ Declarations ------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for C++ declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/DeclVisitor.h" 19#include "clang/AST/TypeOrdering.h" 20#include "clang/AST/StmtVisitor.h" 21#include "clang/Lex/Preprocessor.h" 22#include "clang/Parse/DeclSpec.h" 23#include "llvm/ADT/STLExtras.h" 24#include "llvm/Support/Compiler.h" 25#include <algorithm> // for std::equal 26#include <map> 27 28using namespace clang; 29 30//===----------------------------------------------------------------------===// 31// CheckDefaultArgumentVisitor 32//===----------------------------------------------------------------------===// 33 34namespace { 35 /// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses 36 /// the default argument of a parameter to determine whether it 37 /// contains any ill-formed subexpressions. For example, this will 38 /// diagnose the use of local variables or parameters within the 39 /// default argument expression. 40 class VISIBILITY_HIDDEN CheckDefaultArgumentVisitor 41 : public StmtVisitor<CheckDefaultArgumentVisitor, bool> { 42 Expr *DefaultArg; 43 Sema *S; 44 45 public: 46 CheckDefaultArgumentVisitor(Expr *defarg, Sema *s) 47 : DefaultArg(defarg), S(s) {} 48 49 bool VisitExpr(Expr *Node); 50 bool VisitDeclRefExpr(DeclRefExpr *DRE); 51 bool VisitCXXThisExpr(CXXThisExpr *ThisE); 52 }; 53 54 /// VisitExpr - Visit all of the children of this expression. 55 bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) { 56 bool IsInvalid = false; 57 for (Stmt::child_iterator I = Node->child_begin(), 58 E = Node->child_end(); I != E; ++I) 59 IsInvalid |= Visit(*I); 60 return IsInvalid; 61 } 62 63 /// VisitDeclRefExpr - Visit a reference to a declaration, to 64 /// determine whether this declaration can be used in the default 65 /// argument expression. 66 bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) { 67 NamedDecl *Decl = DRE->getDecl(); 68 if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) { 69 // C++ [dcl.fct.default]p9 70 // Default arguments are evaluated each time the function is 71 // called. The order of evaluation of function arguments is 72 // unspecified. Consequently, parameters of a function shall not 73 // be used in default argument expressions, even if they are not 74 // evaluated. Parameters of a function declared before a default 75 // argument expression are in scope and can hide namespace and 76 // class member names. 77 return S->Diag(DRE->getSourceRange().getBegin(), 78 diag::err_param_default_argument_references_param) 79 << Param->getDeclName() << DefaultArg->getSourceRange(); 80 } else if (VarDecl *VDecl = dyn_cast<VarDecl>(Decl)) { 81 // C++ [dcl.fct.default]p7 82 // Local variables shall not be used in default argument 83 // expressions. 84 if (VDecl->isBlockVarDecl()) 85 return S->Diag(DRE->getSourceRange().getBegin(), 86 diag::err_param_default_argument_references_local) 87 << VDecl->getDeclName() << DefaultArg->getSourceRange(); 88 } 89 90 return false; 91 } 92 93 /// VisitCXXThisExpr - Visit a C++ "this" expression. 94 bool CheckDefaultArgumentVisitor::VisitCXXThisExpr(CXXThisExpr *ThisE) { 95 // C++ [dcl.fct.default]p8: 96 // The keyword this shall not be used in a default argument of a 97 // member function. 98 return S->Diag(ThisE->getSourceRange().getBegin(), 99 diag::err_param_default_argument_references_this) 100 << ThisE->getSourceRange(); 101 } 102} 103 104/// ActOnParamDefaultArgument - Check whether the default argument 105/// provided for a function parameter is well-formed. If so, attach it 106/// to the parameter declaration. 107void 108Sema::ActOnParamDefaultArgument(DeclPtrTy param, SourceLocation EqualLoc, 109 ExprArg defarg) { 110 ParmVarDecl *Param = cast<ParmVarDecl>(param.getAs<Decl>()); 111 ExprOwningPtr<Expr> DefaultArg(this, defarg.takeAs<Expr>()); 112 QualType ParamType = Param->getType(); 113 114 // Default arguments are only permitted in C++ 115 if (!getLangOptions().CPlusPlus) { 116 Diag(EqualLoc, diag::err_param_default_argument) 117 << DefaultArg->getSourceRange(); 118 Param->setInvalidDecl(); 119 return; 120 } 121 122 // C++ [dcl.fct.default]p5 123 // A default argument expression is implicitly converted (clause 124 // 4) to the parameter type. The default argument expression has 125 // the same semantic constraints as the initializer expression in 126 // a declaration of a variable of the parameter type, using the 127 // copy-initialization semantics (8.5). 128 Expr *DefaultArgPtr = DefaultArg.get(); 129 bool DefaultInitFailed = CheckInitializerTypes(DefaultArgPtr, ParamType, 130 EqualLoc, 131 Param->getDeclName(), 132 /*DirectInit=*/false); 133 if (DefaultArgPtr != DefaultArg.get()) { 134 DefaultArg.take(); 135 DefaultArg.reset(DefaultArgPtr); 136 } 137 if (DefaultInitFailed) { 138 return; 139 } 140 141 // Check that the default argument is well-formed 142 CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg.get(), this); 143 if (DefaultArgChecker.Visit(DefaultArg.get())) { 144 Param->setInvalidDecl(); 145 return; 146 } 147 148 // Okay: add the default argument to the parameter 149 Param->setDefaultArg(DefaultArg.take()); 150} 151 152/// ActOnParamUnparsedDefaultArgument - We've seen a default 153/// argument for a function parameter, but we can't parse it yet 154/// because we're inside a class definition. Note that this default 155/// argument will be parsed later. 156void Sema::ActOnParamUnparsedDefaultArgument(DeclPtrTy param, 157 SourceLocation EqualLoc) { 158 ParmVarDecl *Param = cast<ParmVarDecl>(param.getAs<Decl>()); 159 if (Param) 160 Param->setUnparsedDefaultArg(); 161} 162 163/// ActOnParamDefaultArgumentError - Parsing or semantic analysis of 164/// the default argument for the parameter param failed. 165void Sema::ActOnParamDefaultArgumentError(DeclPtrTy param) { 166 cast<ParmVarDecl>(param.getAs<Decl>())->setInvalidDecl(); 167} 168 169/// CheckExtraCXXDefaultArguments - Check for any extra default 170/// arguments in the declarator, which is not a function declaration 171/// or definition and therefore is not permitted to have default 172/// arguments. This routine should be invoked for every declarator 173/// that is not a function declaration or definition. 174void Sema::CheckExtraCXXDefaultArguments(Declarator &D) { 175 // C++ [dcl.fct.default]p3 176 // A default argument expression shall be specified only in the 177 // parameter-declaration-clause of a function declaration or in a 178 // template-parameter (14.1). It shall not be specified for a 179 // parameter pack. If it is specified in a 180 // parameter-declaration-clause, it shall not occur within a 181 // declarator or abstract-declarator of a parameter-declaration. 182 for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) { 183 DeclaratorChunk &chunk = D.getTypeObject(i); 184 if (chunk.Kind == DeclaratorChunk::Function) { 185 for (unsigned argIdx = 0, e = chunk.Fun.NumArgs; argIdx != e; ++argIdx) { 186 ParmVarDecl *Param = 187 cast<ParmVarDecl>(chunk.Fun.ArgInfo[argIdx].Param.getAs<Decl>()); 188 if (Param->hasUnparsedDefaultArg()) { 189 CachedTokens *Toks = chunk.Fun.ArgInfo[argIdx].DefaultArgTokens; 190 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc) 191 << SourceRange((*Toks)[1].getLocation(), Toks->back().getLocation()); 192 delete Toks; 193 chunk.Fun.ArgInfo[argIdx].DefaultArgTokens = 0; 194 } else if (Param->getDefaultArg()) { 195 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc) 196 << Param->getDefaultArg()->getSourceRange(); 197 Param->setDefaultArg(0); 198 } 199 } 200 } 201 } 202} 203 204// MergeCXXFunctionDecl - Merge two declarations of the same C++ 205// function, once we already know that they have the same 206// type. Subroutine of MergeFunctionDecl. Returns true if there was an 207// error, false otherwise. 208bool Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old) { 209 bool Invalid = false; 210 211 // C++ [dcl.fct.default]p4: 212 // 213 // For non-template functions, default arguments can be added in 214 // later declarations of a function in the same 215 // scope. Declarations in different scopes have completely 216 // distinct sets of default arguments. That is, declarations in 217 // inner scopes do not acquire default arguments from 218 // declarations in outer scopes, and vice versa. In a given 219 // function declaration, all parameters subsequent to a 220 // parameter with a default argument shall have default 221 // arguments supplied in this or previous declarations. A 222 // default argument shall not be redefined by a later 223 // declaration (not even to the same value). 224 for (unsigned p = 0, NumParams = Old->getNumParams(); p < NumParams; ++p) { 225 ParmVarDecl *OldParam = Old->getParamDecl(p); 226 ParmVarDecl *NewParam = New->getParamDecl(p); 227 228 if(OldParam->getDefaultArg() && NewParam->getDefaultArg()) { 229 Diag(NewParam->getLocation(), 230 diag::err_param_default_argument_redefinition) 231 << NewParam->getDefaultArg()->getSourceRange(); 232 Diag(OldParam->getLocation(), diag::note_previous_definition); 233 Invalid = true; 234 } else if (OldParam->getDefaultArg()) { 235 // Merge the old default argument into the new parameter 236 NewParam->setDefaultArg(OldParam->getDefaultArg()); 237 } 238 } 239 240 return Invalid; 241} 242 243/// CheckCXXDefaultArguments - Verify that the default arguments for a 244/// function declaration are well-formed according to C++ 245/// [dcl.fct.default]. 246void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) { 247 unsigned NumParams = FD->getNumParams(); 248 unsigned p; 249 250 // Find first parameter with a default argument 251 for (p = 0; p < NumParams; ++p) { 252 ParmVarDecl *Param = FD->getParamDecl(p); 253 if (Param->getDefaultArg()) 254 break; 255 } 256 257 // C++ [dcl.fct.default]p4: 258 // In a given function declaration, all parameters 259 // subsequent to a parameter with a default argument shall 260 // have default arguments supplied in this or previous 261 // declarations. A default argument shall not be redefined 262 // by a later declaration (not even to the same value). 263 unsigned LastMissingDefaultArg = 0; 264 for(; p < NumParams; ++p) { 265 ParmVarDecl *Param = FD->getParamDecl(p); 266 if (!Param->getDefaultArg()) { 267 if (Param->isInvalidDecl()) 268 /* We already complained about this parameter. */; 269 else if (Param->getIdentifier()) 270 Diag(Param->getLocation(), 271 diag::err_param_default_argument_missing_name) 272 << Param->getIdentifier(); 273 else 274 Diag(Param->getLocation(), 275 diag::err_param_default_argument_missing); 276 277 LastMissingDefaultArg = p; 278 } 279 } 280 281 if (LastMissingDefaultArg > 0) { 282 // Some default arguments were missing. Clear out all of the 283 // default arguments up to (and including) the last missing 284 // default argument, so that we leave the function parameters 285 // in a semantically valid state. 286 for (p = 0; p <= LastMissingDefaultArg; ++p) { 287 ParmVarDecl *Param = FD->getParamDecl(p); 288 if (Param->getDefaultArg()) { 289 if (!Param->hasUnparsedDefaultArg()) 290 Param->getDefaultArg()->Destroy(Context); 291 Param->setDefaultArg(0); 292 } 293 } 294 } 295} 296 297/// isCurrentClassName - Determine whether the identifier II is the 298/// name of the class type currently being defined. In the case of 299/// nested classes, this will only return true if II is the name of 300/// the innermost class. 301bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *, 302 const CXXScopeSpec *SS) { 303 CXXRecordDecl *CurDecl; 304 if (SS && SS->isSet() && !SS->isInvalid()) { 305 DeclContext *DC = computeDeclContext(*SS); 306 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC); 307 } else 308 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 309 310 if (CurDecl) 311 return &II == CurDecl->getIdentifier(); 312 else 313 return false; 314} 315 316/// \brief Check the validity of a C++ base class specifier. 317/// 318/// \returns a new CXXBaseSpecifier if well-formed, emits diagnostics 319/// and returns NULL otherwise. 320CXXBaseSpecifier * 321Sema::CheckBaseSpecifier(CXXRecordDecl *Class, 322 SourceRange SpecifierRange, 323 bool Virtual, AccessSpecifier Access, 324 QualType BaseType, 325 SourceLocation BaseLoc) { 326 // C++ [class.union]p1: 327 // A union shall not have base classes. 328 if (Class->isUnion()) { 329 Diag(Class->getLocation(), diag::err_base_clause_on_union) 330 << SpecifierRange; 331 return 0; 332 } 333 334 if (BaseType->isDependentType()) 335 return new CXXBaseSpecifier(SpecifierRange, Virtual, 336 Class->getTagKind() == RecordDecl::TK_class, 337 Access, BaseType); 338 339 // Base specifiers must be record types. 340 if (!BaseType->isRecordType()) { 341 Diag(BaseLoc, diag::err_base_must_be_class) << SpecifierRange; 342 return 0; 343 } 344 345 // C++ [class.union]p1: 346 // A union shall not be used as a base class. 347 if (BaseType->isUnionType()) { 348 Diag(BaseLoc, diag::err_union_as_base_class) << SpecifierRange; 349 return 0; 350 } 351 352 // C++ [class.derived]p2: 353 // The class-name in a base-specifier shall not be an incompletely 354 // defined class. 355 if (RequireCompleteType(BaseLoc, BaseType, diag::err_incomplete_base_class, 356 SpecifierRange)) 357 return 0; 358 359 // If the base class is polymorphic, the new one is, too. 360 RecordDecl *BaseDecl = BaseType->getAsRecordType()->getDecl(); 361 assert(BaseDecl && "Record type has no declaration"); 362 BaseDecl = BaseDecl->getDefinition(Context); 363 assert(BaseDecl && "Base type is not incomplete, but has no definition"); 364 if (cast<CXXRecordDecl>(BaseDecl)->isPolymorphic()) 365 Class->setPolymorphic(true); 366 367 // C++ [dcl.init.aggr]p1: 368 // An aggregate is [...] a class with [...] no base classes [...]. 369 Class->setAggregate(false); 370 Class->setPOD(false); 371 372 if (Virtual) { 373 // C++ [class.ctor]p5: 374 // A constructor is trivial if its class has no virtual base classes. 375 Class->setHasTrivialConstructor(false); 376 } else { 377 // C++ [class.ctor]p5: 378 // A constructor is trivial if all the direct base classes of its 379 // class have trivial constructors. 380 Class->setHasTrivialConstructor(cast<CXXRecordDecl>(BaseDecl)-> 381 hasTrivialConstructor()); 382 } 383 384 // C++ [class.ctor]p3: 385 // A destructor is trivial if all the direct base classes of its class 386 // have trivial destructors. 387 Class->setHasTrivialDestructor(cast<CXXRecordDecl>(BaseDecl)-> 388 hasTrivialDestructor()); 389 390 // Create the base specifier. 391 // FIXME: Allocate via ASTContext? 392 return new CXXBaseSpecifier(SpecifierRange, Virtual, 393 Class->getTagKind() == RecordDecl::TK_class, 394 Access, BaseType); 395} 396 397/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is 398/// one entry in the base class list of a class specifier, for 399/// example: 400/// class foo : public bar, virtual private baz { 401/// 'public bar' and 'virtual private baz' are each base-specifiers. 402Sema::BaseResult 403Sema::ActOnBaseSpecifier(DeclPtrTy classdecl, SourceRange SpecifierRange, 404 bool Virtual, AccessSpecifier Access, 405 TypeTy *basetype, SourceLocation BaseLoc) { 406 AdjustDeclIfTemplate(classdecl); 407 CXXRecordDecl *Class = cast<CXXRecordDecl>(classdecl.getAs<Decl>()); 408 QualType BaseType = QualType::getFromOpaquePtr(basetype); 409 if (CXXBaseSpecifier *BaseSpec = CheckBaseSpecifier(Class, SpecifierRange, 410 Virtual, Access, 411 BaseType, BaseLoc)) 412 return BaseSpec; 413 414 return true; 415} 416 417/// \brief Performs the actual work of attaching the given base class 418/// specifiers to a C++ class. 419bool Sema::AttachBaseSpecifiers(CXXRecordDecl *Class, CXXBaseSpecifier **Bases, 420 unsigned NumBases) { 421 if (NumBases == 0) 422 return false; 423 424 // Used to keep track of which base types we have already seen, so 425 // that we can properly diagnose redundant direct base types. Note 426 // that the key is always the unqualified canonical type of the base 427 // class. 428 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes; 429 430 // Copy non-redundant base specifiers into permanent storage. 431 unsigned NumGoodBases = 0; 432 bool Invalid = false; 433 for (unsigned idx = 0; idx < NumBases; ++idx) { 434 QualType NewBaseType 435 = Context.getCanonicalType(Bases[idx]->getType()); 436 NewBaseType = NewBaseType.getUnqualifiedType(); 437 438 if (KnownBaseTypes[NewBaseType]) { 439 // C++ [class.mi]p3: 440 // A class shall not be specified as a direct base class of a 441 // derived class more than once. 442 Diag(Bases[idx]->getSourceRange().getBegin(), 443 diag::err_duplicate_base_class) 444 << KnownBaseTypes[NewBaseType]->getType() 445 << Bases[idx]->getSourceRange(); 446 447 // Delete the duplicate base class specifier; we're going to 448 // overwrite its pointer later. 449 delete Bases[idx]; 450 451 Invalid = true; 452 } else { 453 // Okay, add this new base class. 454 KnownBaseTypes[NewBaseType] = Bases[idx]; 455 Bases[NumGoodBases++] = Bases[idx]; 456 } 457 } 458 459 // Attach the remaining base class specifiers to the derived class. 460 Class->setBases(Bases, NumGoodBases); 461 462 // Delete the remaining (good) base class specifiers, since their 463 // data has been copied into the CXXRecordDecl. 464 for (unsigned idx = 0; idx < NumGoodBases; ++idx) 465 delete Bases[idx]; 466 467 return Invalid; 468} 469 470/// ActOnBaseSpecifiers - Attach the given base specifiers to the 471/// class, after checking whether there are any duplicate base 472/// classes. 473void Sema::ActOnBaseSpecifiers(DeclPtrTy ClassDecl, BaseTy **Bases, 474 unsigned NumBases) { 475 if (!ClassDecl || !Bases || !NumBases) 476 return; 477 478 AdjustDeclIfTemplate(ClassDecl); 479 AttachBaseSpecifiers(cast<CXXRecordDecl>(ClassDecl.getAs<Decl>()), 480 (CXXBaseSpecifier**)(Bases), NumBases); 481} 482 483//===----------------------------------------------------------------------===// 484// C++ class member Handling 485//===----------------------------------------------------------------------===// 486 487/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member 488/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the 489/// bitfield width if there is one and 'InitExpr' specifies the initializer if 490/// any. 491Sema::DeclPtrTy 492Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D, 493 ExprTy *BW, ExprTy *InitExpr, bool Deleted) { 494 const DeclSpec &DS = D.getDeclSpec(); 495 DeclarationName Name = GetNameForDeclarator(D); 496 Expr *BitWidth = static_cast<Expr*>(BW); 497 Expr *Init = static_cast<Expr*>(InitExpr); 498 SourceLocation Loc = D.getIdentifierLoc(); 499 500 bool isFunc = D.isFunctionDeclarator(); 501 502 // C++ 9.2p6: A member shall not be declared to have automatic storage 503 // duration (auto, register) or with the extern storage-class-specifier. 504 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class 505 // data members and cannot be applied to names declared const or static, 506 // and cannot be applied to reference members. 507 switch (DS.getStorageClassSpec()) { 508 case DeclSpec::SCS_unspecified: 509 case DeclSpec::SCS_typedef: 510 case DeclSpec::SCS_static: 511 // FALL THROUGH. 512 break; 513 case DeclSpec::SCS_mutable: 514 if (isFunc) { 515 if (DS.getStorageClassSpecLoc().isValid()) 516 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_function); 517 else 518 Diag(DS.getThreadSpecLoc(), diag::err_mutable_function); 519 520 // FIXME: It would be nicer if the keyword was ignored only for this 521 // declarator. Otherwise we could get follow-up errors. 522 D.getMutableDeclSpec().ClearStorageClassSpecs(); 523 } else { 524 QualType T = GetTypeForDeclarator(D, S); 525 diag::kind err = static_cast<diag::kind>(0); 526 if (T->isReferenceType()) 527 err = diag::err_mutable_reference; 528 else if (T.isConstQualified()) 529 err = diag::err_mutable_const; 530 if (err != 0) { 531 if (DS.getStorageClassSpecLoc().isValid()) 532 Diag(DS.getStorageClassSpecLoc(), err); 533 else 534 Diag(DS.getThreadSpecLoc(), err); 535 // FIXME: It would be nicer if the keyword was ignored only for this 536 // declarator. Otherwise we could get follow-up errors. 537 D.getMutableDeclSpec().ClearStorageClassSpecs(); 538 } 539 } 540 break; 541 default: 542 if (DS.getStorageClassSpecLoc().isValid()) 543 Diag(DS.getStorageClassSpecLoc(), 544 diag::err_storageclass_invalid_for_member); 545 else 546 Diag(DS.getThreadSpecLoc(), diag::err_storageclass_invalid_for_member); 547 D.getMutableDeclSpec().ClearStorageClassSpecs(); 548 } 549 550 if (!isFunc && 551 D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_typename && 552 D.getNumTypeObjects() == 0) { 553 // Check also for this case: 554 // 555 // typedef int f(); 556 // f a; 557 // 558 QualType TDType = QualType::getFromOpaquePtr(DS.getTypeRep()); 559 isFunc = TDType->isFunctionType(); 560 } 561 562 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified || 563 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) && 564 !isFunc); 565 566 Decl *Member; 567 if (isInstField) { 568 Member = HandleField(S, cast<CXXRecordDecl>(CurContext), Loc, D, BitWidth, 569 AS); 570 assert(Member && "HandleField never returns null"); 571 } else { 572 Member = ActOnDeclarator(S, D).getAs<Decl>(); 573 if (!Member) { 574 if (BitWidth) DeleteExpr(BitWidth); 575 return DeclPtrTy(); 576 } 577 578 // Non-instance-fields can't have a bitfield. 579 if (BitWidth) { 580 if (Member->isInvalidDecl()) { 581 // don't emit another diagnostic. 582 } else if (isa<VarDecl>(Member)) { 583 // C++ 9.6p3: A bit-field shall not be a static member. 584 // "static member 'A' cannot be a bit-field" 585 Diag(Loc, diag::err_static_not_bitfield) 586 << Name << BitWidth->getSourceRange(); 587 } else if (isa<TypedefDecl>(Member)) { 588 // "typedef member 'x' cannot be a bit-field" 589 Diag(Loc, diag::err_typedef_not_bitfield) 590 << Name << BitWidth->getSourceRange(); 591 } else { 592 // A function typedef ("typedef int f(); f a;"). 593 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 594 Diag(Loc, diag::err_not_integral_type_bitfield) 595 << Name << cast<ValueDecl>(Member)->getType() 596 << BitWidth->getSourceRange(); 597 } 598 599 DeleteExpr(BitWidth); 600 BitWidth = 0; 601 Member->setInvalidDecl(); 602 } 603 604 Member->setAccess(AS); 605 } 606 607 assert((Name || isInstField) && "No identifier for non-field ?"); 608 609 if (Init) 610 AddInitializerToDecl(DeclPtrTy::make(Member), ExprArg(*this, Init), false); 611 if (Deleted) // FIXME: Source location is not very good. 612 SetDeclDeleted(DeclPtrTy::make(Member), D.getSourceRange().getBegin()); 613 614 if (isInstField) { 615 FieldCollector->Add(cast<FieldDecl>(Member)); 616 return DeclPtrTy(); 617 } 618 return DeclPtrTy::make(Member); 619} 620 621/// ActOnMemInitializer - Handle a C++ member initializer. 622Sema::MemInitResult 623Sema::ActOnMemInitializer(DeclPtrTy ConstructorD, 624 Scope *S, 625 IdentifierInfo *MemberOrBase, 626 SourceLocation IdLoc, 627 SourceLocation LParenLoc, 628 ExprTy **Args, unsigned NumArgs, 629 SourceLocation *CommaLocs, 630 SourceLocation RParenLoc) { 631 CXXConstructorDecl *Constructor 632 = dyn_cast<CXXConstructorDecl>(ConstructorD.getAs<Decl>()); 633 if (!Constructor) { 634 // The user wrote a constructor initializer on a function that is 635 // not a C++ constructor. Ignore the error for now, because we may 636 // have more member initializers coming; we'll diagnose it just 637 // once in ActOnMemInitializers. 638 return true; 639 } 640 641 CXXRecordDecl *ClassDecl = Constructor->getParent(); 642 643 // C++ [class.base.init]p2: 644 // Names in a mem-initializer-id are looked up in the scope of the 645 // constructor’s class and, if not found in that scope, are looked 646 // up in the scope containing the constructor’s 647 // definition. [Note: if the constructor’s class contains a member 648 // with the same name as a direct or virtual base class of the 649 // class, a mem-initializer-id naming the member or base class and 650 // composed of a single identifier refers to the class member. A 651 // mem-initializer-id for the hidden base class may be specified 652 // using a qualified name. ] 653 // Look for a member, first. 654 FieldDecl *Member = 0; 655 DeclContext::lookup_result Result 656 = ClassDecl->lookup(Context, MemberOrBase); 657 if (Result.first != Result.second) 658 Member = dyn_cast<FieldDecl>(*Result.first); 659 660 // FIXME: Handle members of an anonymous union. 661 662 if (Member) { 663 // FIXME: Perform direct initialization of the member. 664 return new CXXBaseOrMemberInitializer(Member, (Expr **)Args, NumArgs); 665 } 666 667 // It didn't name a member, so see if it names a class. 668 TypeTy *BaseTy = getTypeName(*MemberOrBase, IdLoc, S, 0/*SS*/); 669 if (!BaseTy) 670 return Diag(IdLoc, diag::err_mem_init_not_member_or_class) 671 << MemberOrBase << SourceRange(IdLoc, RParenLoc); 672 673 QualType BaseType = QualType::getFromOpaquePtr(BaseTy); 674 if (!BaseType->isRecordType()) 675 return Diag(IdLoc, diag::err_base_init_does_not_name_class) 676 << BaseType << SourceRange(IdLoc, RParenLoc); 677 678 // C++ [class.base.init]p2: 679 // [...] Unless the mem-initializer-id names a nonstatic data 680 // member of the constructor’s class or a direct or virtual base 681 // of that class, the mem-initializer is ill-formed. A 682 // mem-initializer-list can initialize a base class using any 683 // name that denotes that base class type. 684 685 // First, check for a direct base class. 686 const CXXBaseSpecifier *DirectBaseSpec = 0; 687 for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin(); 688 Base != ClassDecl->bases_end(); ++Base) { 689 if (Context.getCanonicalType(BaseType).getUnqualifiedType() == 690 Context.getCanonicalType(Base->getType()).getUnqualifiedType()) { 691 // We found a direct base of this type. That's what we're 692 // initializing. 693 DirectBaseSpec = &*Base; 694 break; 695 } 696 } 697 698 // Check for a virtual base class. 699 // FIXME: We might be able to short-circuit this if we know in advance that 700 // there are no virtual bases. 701 const CXXBaseSpecifier *VirtualBaseSpec = 0; 702 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) { 703 // We haven't found a base yet; search the class hierarchy for a 704 // virtual base class. 705 BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 706 /*DetectVirtual=*/false); 707 if (IsDerivedFrom(Context.getTypeDeclType(ClassDecl), BaseType, Paths)) { 708 for (BasePaths::paths_iterator Path = Paths.begin(); 709 Path != Paths.end(); ++Path) { 710 if (Path->back().Base->isVirtual()) { 711 VirtualBaseSpec = Path->back().Base; 712 break; 713 } 714 } 715 } 716 } 717 718 // C++ [base.class.init]p2: 719 // If a mem-initializer-id is ambiguous because it designates both 720 // a direct non-virtual base class and an inherited virtual base 721 // class, the mem-initializer is ill-formed. 722 if (DirectBaseSpec && VirtualBaseSpec) 723 return Diag(IdLoc, diag::err_base_init_direct_and_virtual) 724 << MemberOrBase << SourceRange(IdLoc, RParenLoc); 725 726 return new CXXBaseOrMemberInitializer(BaseType, (Expr **)Args, NumArgs); 727} 728 729void Sema::ActOnMemInitializers(DeclPtrTy ConstructorDecl, 730 SourceLocation ColonLoc, 731 MemInitTy **MemInits, unsigned NumMemInits) { 732 CXXConstructorDecl *Constructor = 733 dyn_cast<CXXConstructorDecl>(ConstructorDecl.getAs<Decl>()); 734 735 if (!Constructor) { 736 Diag(ColonLoc, diag::err_only_constructors_take_base_inits); 737 return; 738 } 739} 740 741namespace { 742 /// PureVirtualMethodCollector - traverses a class and its superclasses 743 /// and determines if it has any pure virtual methods. 744 class VISIBILITY_HIDDEN PureVirtualMethodCollector { 745 ASTContext &Context; 746 747 public: 748 typedef llvm::SmallVector<const CXXMethodDecl*, 8> MethodList; 749 750 private: 751 MethodList Methods; 752 753 void Collect(const CXXRecordDecl* RD, MethodList& Methods); 754 755 public: 756 PureVirtualMethodCollector(ASTContext &Ctx, const CXXRecordDecl* RD) 757 : Context(Ctx) { 758 759 MethodList List; 760 Collect(RD, List); 761 762 // Copy the temporary list to methods, and make sure to ignore any 763 // null entries. 764 for (size_t i = 0, e = List.size(); i != e; ++i) { 765 if (List[i]) 766 Methods.push_back(List[i]); 767 } 768 } 769 770 bool empty() const { return Methods.empty(); } 771 772 MethodList::const_iterator methods_begin() { return Methods.begin(); } 773 MethodList::const_iterator methods_end() { return Methods.end(); } 774 }; 775 776 void PureVirtualMethodCollector::Collect(const CXXRecordDecl* RD, 777 MethodList& Methods) { 778 // First, collect the pure virtual methods for the base classes. 779 for (CXXRecordDecl::base_class_const_iterator Base = RD->bases_begin(), 780 BaseEnd = RD->bases_end(); Base != BaseEnd; ++Base) { 781 if (const RecordType *RT = Base->getType()->getAsRecordType()) { 782 const CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(RT->getDecl()); 783 if (BaseDecl && BaseDecl->isAbstract()) 784 Collect(BaseDecl, Methods); 785 } 786 } 787 788 // Next, zero out any pure virtual methods that this class overrides. 789 typedef llvm::SmallPtrSet<const CXXMethodDecl*, 4> MethodSetTy; 790 791 MethodSetTy OverriddenMethods; 792 size_t MethodsSize = Methods.size(); 793 794 for (RecordDecl::decl_iterator i = RD->decls_begin(Context), 795 e = RD->decls_end(Context); 796 i != e; ++i) { 797 // Traverse the record, looking for methods. 798 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*i)) { 799 // If the method is pre virtual, add it to the methods vector. 800 if (MD->isPure()) { 801 Methods.push_back(MD); 802 continue; 803 } 804 805 // Otherwise, record all the overridden methods in our set. 806 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(), 807 E = MD->end_overridden_methods(); I != E; ++I) { 808 // Keep track of the overridden methods. 809 OverriddenMethods.insert(*I); 810 } 811 } 812 } 813 814 // Now go through the methods and zero out all the ones we know are 815 // overridden. 816 for (size_t i = 0, e = MethodsSize; i != e; ++i) { 817 if (OverriddenMethods.count(Methods[i])) 818 Methods[i] = 0; 819 } 820 821 } 822} 823 824bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T, 825 unsigned DiagID, AbstractDiagSelID SelID, 826 const CXXRecordDecl *CurrentRD) { 827 828 if (!getLangOptions().CPlusPlus) 829 return false; 830 831 if (const ArrayType *AT = Context.getAsArrayType(T)) 832 return RequireNonAbstractType(Loc, AT->getElementType(), DiagID, SelID, 833 CurrentRD); 834 835 if (const PointerType *PT = T->getAsPointerType()) { 836 // Find the innermost pointer type. 837 while (const PointerType *T = PT->getPointeeType()->getAsPointerType()) 838 PT = T; 839 840 if (const ArrayType *AT = Context.getAsArrayType(PT->getPointeeType())) 841 return RequireNonAbstractType(Loc, AT->getElementType(), DiagID, SelID, 842 CurrentRD); 843 } 844 845 const RecordType *RT = T->getAsRecordType(); 846 if (!RT) 847 return false; 848 849 const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()); 850 if (!RD) 851 return false; 852 853 if (CurrentRD && CurrentRD != RD) 854 return false; 855 856 if (!RD->isAbstract()) 857 return false; 858 859 Diag(Loc, DiagID) << RD->getDeclName() << SelID; 860 861 // Check if we've already emitted the list of pure virtual functions for this 862 // class. 863 if (PureVirtualClassDiagSet && PureVirtualClassDiagSet->count(RD)) 864 return true; 865 866 PureVirtualMethodCollector Collector(Context, RD); 867 868 for (PureVirtualMethodCollector::MethodList::const_iterator I = 869 Collector.methods_begin(), E = Collector.methods_end(); I != E; ++I) { 870 const CXXMethodDecl *MD = *I; 871 872 Diag(MD->getLocation(), diag::note_pure_virtual_function) << 873 MD->getDeclName(); 874 } 875 876 if (!PureVirtualClassDiagSet) 877 PureVirtualClassDiagSet.reset(new RecordDeclSetTy); 878 PureVirtualClassDiagSet->insert(RD); 879 880 return true; 881} 882 883namespace { 884 class VISIBILITY_HIDDEN AbstractClassUsageDiagnoser 885 : public DeclVisitor<AbstractClassUsageDiagnoser, bool> { 886 Sema &SemaRef; 887 CXXRecordDecl *AbstractClass; 888 889 bool VisitDeclContext(const DeclContext *DC) { 890 bool Invalid = false; 891 892 for (CXXRecordDecl::decl_iterator I = DC->decls_begin(SemaRef.Context), 893 E = DC->decls_end(SemaRef.Context); I != E; ++I) 894 Invalid |= Visit(*I); 895 896 return Invalid; 897 } 898 899 public: 900 AbstractClassUsageDiagnoser(Sema& SemaRef, CXXRecordDecl *ac) 901 : SemaRef(SemaRef), AbstractClass(ac) { 902 Visit(SemaRef.Context.getTranslationUnitDecl()); 903 } 904 905 bool VisitFunctionDecl(const FunctionDecl *FD) { 906 if (FD->isThisDeclarationADefinition()) { 907 // No need to do the check if we're in a definition, because it requires 908 // that the return/param types are complete. 909 // because that requires 910 return VisitDeclContext(FD); 911 } 912 913 // Check the return type. 914 QualType RTy = FD->getType()->getAsFunctionType()->getResultType(); 915 bool Invalid = 916 SemaRef.RequireNonAbstractType(FD->getLocation(), RTy, 917 diag::err_abstract_type_in_decl, 918 Sema::AbstractReturnType, 919 AbstractClass); 920 921 for (FunctionDecl::param_const_iterator I = FD->param_begin(), 922 E = FD->param_end(); I != E; ++I) { 923 const ParmVarDecl *VD = *I; 924 Invalid |= 925 SemaRef.RequireNonAbstractType(VD->getLocation(), 926 VD->getOriginalType(), 927 diag::err_abstract_type_in_decl, 928 Sema::AbstractParamType, 929 AbstractClass); 930 } 931 932 return Invalid; 933 } 934 935 bool VisitDecl(const Decl* D) { 936 if (const DeclContext *DC = dyn_cast<DeclContext>(D)) 937 return VisitDeclContext(DC); 938 939 return false; 940 } 941 }; 942} 943 944void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc, 945 DeclPtrTy TagDecl, 946 SourceLocation LBrac, 947 SourceLocation RBrac) { 948 AdjustDeclIfTemplate(TagDecl); 949 ActOnFields(S, RLoc, TagDecl, 950 (DeclPtrTy*)FieldCollector->getCurFields(), 951 FieldCollector->getCurNumFields(), LBrac, RBrac, 0); 952 953 CXXRecordDecl *RD = cast<CXXRecordDecl>(TagDecl.getAs<Decl>()); 954 if (!RD->isAbstract()) { 955 // Collect all the pure virtual methods and see if this is an abstract 956 // class after all. 957 PureVirtualMethodCollector Collector(Context, RD); 958 if (!Collector.empty()) 959 RD->setAbstract(true); 960 } 961 962 if (RD->isAbstract()) 963 AbstractClassUsageDiagnoser(*this, RD); 964 965 if (RD->hasTrivialConstructor() || RD->hasTrivialDestructor()) { 966 for (RecordDecl::field_iterator i = RD->field_begin(Context), 967 e = RD->field_end(Context); i != e; ++i) { 968 // All the nonstatic data members must have trivial constructors. 969 QualType FTy = i->getType(); 970 while (const ArrayType *AT = Context.getAsArrayType(FTy)) 971 FTy = AT->getElementType(); 972 973 if (const RecordType *RT = FTy->getAsRecordType()) { 974 CXXRecordDecl *FieldRD = cast<CXXRecordDecl>(RT->getDecl()); 975 976 if (!FieldRD->hasTrivialConstructor()) 977 RD->setHasTrivialConstructor(false); 978 if (!FieldRD->hasTrivialDestructor()) 979 RD->setHasTrivialDestructor(false); 980 981 // If RD has neither a trivial constructor nor a trivial destructor 982 // we don't need to continue checking. 983 if (!RD->hasTrivialConstructor() && !RD->hasTrivialDestructor()) 984 break; 985 } 986 } 987 } 988 989 if (!RD->isDependentType()) 990 AddImplicitlyDeclaredMembersToClass(RD); 991} 992 993/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared 994/// special functions, such as the default constructor, copy 995/// constructor, or destructor, to the given C++ class (C++ 996/// [special]p1). This routine can only be executed just before the 997/// definition of the class is complete. 998void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) { 999 QualType ClassType = Context.getTypeDeclType(ClassDecl); 1000 ClassType = Context.getCanonicalType(ClassType); 1001 1002 if (!ClassDecl->hasUserDeclaredConstructor()) { 1003 // C++ [class.ctor]p5: 1004 // A default constructor for a class X is a constructor of class X 1005 // that can be called without an argument. If there is no 1006 // user-declared constructor for class X, a default constructor is 1007 // implicitly declared. An implicitly-declared default constructor 1008 // is an inline public member of its class. 1009 DeclarationName Name 1010 = Context.DeclarationNames.getCXXConstructorName(ClassType); 1011 CXXConstructorDecl *DefaultCon = 1012 CXXConstructorDecl::Create(Context, ClassDecl, 1013 ClassDecl->getLocation(), Name, 1014 Context.getFunctionType(Context.VoidTy, 1015 0, 0, false, 0), 1016 /*isExplicit=*/false, 1017 /*isInline=*/true, 1018 /*isImplicitlyDeclared=*/true); 1019 DefaultCon->setAccess(AS_public); 1020 DefaultCon->setImplicit(); 1021 ClassDecl->addDecl(Context, DefaultCon); 1022 1023 // Notify the class that we've added a constructor. 1024 ClassDecl->addedConstructor(Context, DefaultCon); 1025 } 1026 1027 if (!ClassDecl->hasUserDeclaredCopyConstructor()) { 1028 // C++ [class.copy]p4: 1029 // If the class definition does not explicitly declare a copy 1030 // constructor, one is declared implicitly. 1031 1032 // C++ [class.copy]p5: 1033 // The implicitly-declared copy constructor for a class X will 1034 // have the form 1035 // 1036 // X::X(const X&) 1037 // 1038 // if 1039 bool HasConstCopyConstructor = true; 1040 1041 // -- each direct or virtual base class B of X has a copy 1042 // constructor whose first parameter is of type const B& or 1043 // const volatile B&, and 1044 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 1045 HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { 1046 const CXXRecordDecl *BaseClassDecl 1047 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 1048 HasConstCopyConstructor 1049 = BaseClassDecl->hasConstCopyConstructor(Context); 1050 } 1051 1052 // -- for all the nonstatic data members of X that are of a 1053 // class type M (or array thereof), each such class type 1054 // has a copy constructor whose first parameter is of type 1055 // const M& or const volatile M&. 1056 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(Context); 1057 HasConstCopyConstructor && Field != ClassDecl->field_end(Context); 1058 ++Field) { 1059 QualType FieldType = (*Field)->getType(); 1060 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 1061 FieldType = Array->getElementType(); 1062 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 1063 const CXXRecordDecl *FieldClassDecl 1064 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 1065 HasConstCopyConstructor 1066 = FieldClassDecl->hasConstCopyConstructor(Context); 1067 } 1068 } 1069 1070 // Otherwise, the implicitly declared copy constructor will have 1071 // the form 1072 // 1073 // X::X(X&) 1074 QualType ArgType = ClassType; 1075 if (HasConstCopyConstructor) 1076 ArgType = ArgType.withConst(); 1077 ArgType = Context.getLValueReferenceType(ArgType); 1078 1079 // An implicitly-declared copy constructor is an inline public 1080 // member of its class. 1081 DeclarationName Name 1082 = Context.DeclarationNames.getCXXConstructorName(ClassType); 1083 CXXConstructorDecl *CopyConstructor 1084 = CXXConstructorDecl::Create(Context, ClassDecl, 1085 ClassDecl->getLocation(), Name, 1086 Context.getFunctionType(Context.VoidTy, 1087 &ArgType, 1, 1088 false, 0), 1089 /*isExplicit=*/false, 1090 /*isInline=*/true, 1091 /*isImplicitlyDeclared=*/true); 1092 CopyConstructor->setAccess(AS_public); 1093 CopyConstructor->setImplicit(); 1094 1095 // Add the parameter to the constructor. 1096 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, 1097 ClassDecl->getLocation(), 1098 /*IdentifierInfo=*/0, 1099 ArgType, VarDecl::None, 0); 1100 CopyConstructor->setParams(Context, &FromParam, 1); 1101 1102 ClassDecl->addedConstructor(Context, CopyConstructor); 1103 ClassDecl->addDecl(Context, CopyConstructor); 1104 } 1105 1106 if (!ClassDecl->hasUserDeclaredCopyAssignment()) { 1107 // Note: The following rules are largely analoguous to the copy 1108 // constructor rules. Note that virtual bases are not taken into account 1109 // for determining the argument type of the operator. Note also that 1110 // operators taking an object instead of a reference are allowed. 1111 // 1112 // C++ [class.copy]p10: 1113 // If the class definition does not explicitly declare a copy 1114 // assignment operator, one is declared implicitly. 1115 // The implicitly-defined copy assignment operator for a class X 1116 // will have the form 1117 // 1118 // X& X::operator=(const X&) 1119 // 1120 // if 1121 bool HasConstCopyAssignment = true; 1122 1123 // -- each direct base class B of X has a copy assignment operator 1124 // whose parameter is of type const B&, const volatile B& or B, 1125 // and 1126 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 1127 HasConstCopyAssignment && Base != ClassDecl->bases_end(); ++Base) { 1128 const CXXRecordDecl *BaseClassDecl 1129 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 1130 HasConstCopyAssignment = BaseClassDecl->hasConstCopyAssignment(Context); 1131 } 1132 1133 // -- for all the nonstatic data members of X that are of a class 1134 // type M (or array thereof), each such class type has a copy 1135 // assignment operator whose parameter is of type const M&, 1136 // const volatile M& or M. 1137 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(Context); 1138 HasConstCopyAssignment && Field != ClassDecl->field_end(Context); 1139 ++Field) { 1140 QualType FieldType = (*Field)->getType(); 1141 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 1142 FieldType = Array->getElementType(); 1143 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 1144 const CXXRecordDecl *FieldClassDecl 1145 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 1146 HasConstCopyAssignment 1147 = FieldClassDecl->hasConstCopyAssignment(Context); 1148 } 1149 } 1150 1151 // Otherwise, the implicitly declared copy assignment operator will 1152 // have the form 1153 // 1154 // X& X::operator=(X&) 1155 QualType ArgType = ClassType; 1156 QualType RetType = Context.getLValueReferenceType(ArgType); 1157 if (HasConstCopyAssignment) 1158 ArgType = ArgType.withConst(); 1159 ArgType = Context.getLValueReferenceType(ArgType); 1160 1161 // An implicitly-declared copy assignment operator is an inline public 1162 // member of its class. 1163 DeclarationName Name = 1164 Context.DeclarationNames.getCXXOperatorName(OO_Equal); 1165 CXXMethodDecl *CopyAssignment = 1166 CXXMethodDecl::Create(Context, ClassDecl, ClassDecl->getLocation(), Name, 1167 Context.getFunctionType(RetType, &ArgType, 1, 1168 false, 0), 1169 /*isStatic=*/false, /*isInline=*/true); 1170 CopyAssignment->setAccess(AS_public); 1171 CopyAssignment->setImplicit(); 1172 1173 // Add the parameter to the operator. 1174 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyAssignment, 1175 ClassDecl->getLocation(), 1176 /*IdentifierInfo=*/0, 1177 ArgType, VarDecl::None, 0); 1178 CopyAssignment->setParams(Context, &FromParam, 1); 1179 1180 // Don't call addedAssignmentOperator. There is no way to distinguish an 1181 // implicit from an explicit assignment operator. 1182 ClassDecl->addDecl(Context, CopyAssignment); 1183 } 1184 1185 if (!ClassDecl->hasUserDeclaredDestructor()) { 1186 // C++ [class.dtor]p2: 1187 // If a class has no user-declared destructor, a destructor is 1188 // declared implicitly. An implicitly-declared destructor is an 1189 // inline public member of its class. 1190 DeclarationName Name 1191 = Context.DeclarationNames.getCXXDestructorName(ClassType); 1192 CXXDestructorDecl *Destructor 1193 = CXXDestructorDecl::Create(Context, ClassDecl, 1194 ClassDecl->getLocation(), Name, 1195 Context.getFunctionType(Context.VoidTy, 1196 0, 0, false, 0), 1197 /*isInline=*/true, 1198 /*isImplicitlyDeclared=*/true); 1199 Destructor->setAccess(AS_public); 1200 Destructor->setImplicit(); 1201 ClassDecl->addDecl(Context, Destructor); 1202 } 1203} 1204 1205/// ActOnStartDelayedCXXMethodDeclaration - We have completed 1206/// parsing a top-level (non-nested) C++ class, and we are now 1207/// parsing those parts of the given Method declaration that could 1208/// not be parsed earlier (C++ [class.mem]p2), such as default 1209/// arguments. This action should enter the scope of the given 1210/// Method declaration as if we had just parsed the qualified method 1211/// name. However, it should not bring the parameters into scope; 1212/// that will be performed by ActOnDelayedCXXMethodParameter. 1213void Sema::ActOnStartDelayedCXXMethodDeclaration(Scope *S, DeclPtrTy MethodD) { 1214 CXXScopeSpec SS; 1215 FunctionDecl *Method = cast<FunctionDecl>(MethodD.getAs<Decl>()); 1216 QualType ClassTy 1217 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 1218 SS.setScopeRep( 1219 NestedNameSpecifier::Create(Context, 0, false, ClassTy.getTypePtr())); 1220 ActOnCXXEnterDeclaratorScope(S, SS); 1221} 1222 1223/// ActOnDelayedCXXMethodParameter - We've already started a delayed 1224/// C++ method declaration. We're (re-)introducing the given 1225/// function parameter into scope for use in parsing later parts of 1226/// the method declaration. For example, we could see an 1227/// ActOnParamDefaultArgument event for this parameter. 1228void Sema::ActOnDelayedCXXMethodParameter(Scope *S, DeclPtrTy ParamD) { 1229 ParmVarDecl *Param = cast<ParmVarDecl>(ParamD.getAs<Decl>()); 1230 1231 // If this parameter has an unparsed default argument, clear it out 1232 // to make way for the parsed default argument. 1233 if (Param->hasUnparsedDefaultArg()) 1234 Param->setDefaultArg(0); 1235 1236 S->AddDecl(DeclPtrTy::make(Param)); 1237 if (Param->getDeclName()) 1238 IdResolver.AddDecl(Param); 1239} 1240 1241/// ActOnFinishDelayedCXXMethodDeclaration - We have finished 1242/// processing the delayed method declaration for Method. The method 1243/// declaration is now considered finished. There may be a separate 1244/// ActOnStartOfFunctionDef action later (not necessarily 1245/// immediately!) for this method, if it was also defined inside the 1246/// class body. 1247void Sema::ActOnFinishDelayedCXXMethodDeclaration(Scope *S, DeclPtrTy MethodD) { 1248 FunctionDecl *Method = cast<FunctionDecl>(MethodD.getAs<Decl>()); 1249 CXXScopeSpec SS; 1250 QualType ClassTy 1251 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 1252 SS.setScopeRep( 1253 NestedNameSpecifier::Create(Context, 0, false, ClassTy.getTypePtr())); 1254 ActOnCXXExitDeclaratorScope(S, SS); 1255 1256 // Now that we have our default arguments, check the constructor 1257 // again. It could produce additional diagnostics or affect whether 1258 // the class has implicitly-declared destructors, among other 1259 // things. 1260 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Method)) 1261 CheckConstructor(Constructor); 1262 1263 // Check the default arguments, which we may have added. 1264 if (!Method->isInvalidDecl()) 1265 CheckCXXDefaultArguments(Method); 1266} 1267 1268/// CheckConstructorDeclarator - Called by ActOnDeclarator to check 1269/// the well-formedness of the constructor declarator @p D with type @p 1270/// R. If there are any errors in the declarator, this routine will 1271/// emit diagnostics and set the invalid bit to true. In any case, the type 1272/// will be updated to reflect a well-formed type for the constructor and 1273/// returned. 1274QualType Sema::CheckConstructorDeclarator(Declarator &D, QualType R, 1275 FunctionDecl::StorageClass &SC) { 1276 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1277 1278 // C++ [class.ctor]p3: 1279 // A constructor shall not be virtual (10.3) or static (9.4). A 1280 // constructor can be invoked for a const, volatile or const 1281 // volatile object. A constructor shall not be declared const, 1282 // volatile, or const volatile (9.3.2). 1283 if (isVirtual) { 1284 if (!D.isInvalidType()) 1285 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be) 1286 << "virtual" << SourceRange(D.getDeclSpec().getVirtualSpecLoc()) 1287 << SourceRange(D.getIdentifierLoc()); 1288 D.setInvalidType(); 1289 } 1290 if (SC == FunctionDecl::Static) { 1291 if (!D.isInvalidType()) 1292 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be) 1293 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1294 << SourceRange(D.getIdentifierLoc()); 1295 D.setInvalidType(); 1296 SC = FunctionDecl::None; 1297 } 1298 1299 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1300 if (FTI.TypeQuals != 0) { 1301 if (FTI.TypeQuals & QualType::Const) 1302 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1303 << "const" << SourceRange(D.getIdentifierLoc()); 1304 if (FTI.TypeQuals & QualType::Volatile) 1305 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1306 << "volatile" << SourceRange(D.getIdentifierLoc()); 1307 if (FTI.TypeQuals & QualType::Restrict) 1308 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1309 << "restrict" << SourceRange(D.getIdentifierLoc()); 1310 } 1311 1312 // Rebuild the function type "R" without any type qualifiers (in 1313 // case any of the errors above fired) and with "void" as the 1314 // return type, since constructors don't have return types. We 1315 // *always* have to do this, because GetTypeForDeclarator will 1316 // put in a result type of "int" when none was specified. 1317 const FunctionProtoType *Proto = R->getAsFunctionProtoType(); 1318 return Context.getFunctionType(Context.VoidTy, Proto->arg_type_begin(), 1319 Proto->getNumArgs(), 1320 Proto->isVariadic(), 0); 1321} 1322 1323/// CheckConstructor - Checks a fully-formed constructor for 1324/// well-formedness, issuing any diagnostics required. Returns true if 1325/// the constructor declarator is invalid. 1326void Sema::CheckConstructor(CXXConstructorDecl *Constructor) { 1327 CXXRecordDecl *ClassDecl 1328 = dyn_cast<CXXRecordDecl>(Constructor->getDeclContext()); 1329 if (!ClassDecl) 1330 return Constructor->setInvalidDecl(); 1331 1332 // C++ [class.copy]p3: 1333 // A declaration of a constructor for a class X is ill-formed if 1334 // its first parameter is of type (optionally cv-qualified) X and 1335 // either there are no other parameters or else all other 1336 // parameters have default arguments. 1337 if (!Constructor->isInvalidDecl() && 1338 ((Constructor->getNumParams() == 1) || 1339 (Constructor->getNumParams() > 1 && 1340 Constructor->getParamDecl(1)->getDefaultArg() != 0))) { 1341 QualType ParamType = Constructor->getParamDecl(0)->getType(); 1342 QualType ClassTy = Context.getTagDeclType(ClassDecl); 1343 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { 1344 SourceLocation ParamLoc = Constructor->getParamDecl(0)->getLocation(); 1345 Diag(ParamLoc, diag::err_constructor_byvalue_arg) 1346 << CodeModificationHint::CreateInsertion(ParamLoc, " const &"); 1347 Constructor->setInvalidDecl(); 1348 } 1349 } 1350 1351 // Notify the class that we've added a constructor. 1352 ClassDecl->addedConstructor(Context, Constructor); 1353} 1354 1355static inline bool 1356FTIHasSingleVoidArgument(DeclaratorChunk::FunctionTypeInfo &FTI) { 1357 return (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1358 FTI.ArgInfo[0].Param && 1359 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()); 1360} 1361 1362/// CheckDestructorDeclarator - Called by ActOnDeclarator to check 1363/// the well-formednes of the destructor declarator @p D with type @p 1364/// R. If there are any errors in the declarator, this routine will 1365/// emit diagnostics and set the declarator to invalid. Even if this happens, 1366/// will be updated to reflect a well-formed type for the destructor and 1367/// returned. 1368QualType Sema::CheckDestructorDeclarator(Declarator &D, 1369 FunctionDecl::StorageClass& SC) { 1370 // C++ [class.dtor]p1: 1371 // [...] A typedef-name that names a class is a class-name 1372 // (7.1.3); however, a typedef-name that names a class shall not 1373 // be used as the identifier in the declarator for a destructor 1374 // declaration. 1375 QualType DeclaratorType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1376 if (isa<TypedefType>(DeclaratorType)) { 1377 Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name) 1378 << DeclaratorType; 1379 D.setInvalidType(); 1380 } 1381 1382 // C++ [class.dtor]p2: 1383 // A destructor is used to destroy objects of its class type. A 1384 // destructor takes no parameters, and no return type can be 1385 // specified for it (not even void). The address of a destructor 1386 // shall not be taken. A destructor shall not be static. A 1387 // destructor can be invoked for a const, volatile or const 1388 // volatile object. A destructor shall not be declared const, 1389 // volatile or const volatile (9.3.2). 1390 if (SC == FunctionDecl::Static) { 1391 if (!D.isInvalidType()) 1392 Diag(D.getIdentifierLoc(), diag::err_destructor_cannot_be) 1393 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1394 << SourceRange(D.getIdentifierLoc()); 1395 SC = FunctionDecl::None; 1396 D.setInvalidType(); 1397 } 1398 if (D.getDeclSpec().hasTypeSpecifier() && !D.isInvalidType()) { 1399 // Destructors don't have return types, but the parser will 1400 // happily parse something like: 1401 // 1402 // class X { 1403 // float ~X(); 1404 // }; 1405 // 1406 // The return type will be eliminated later. 1407 Diag(D.getIdentifierLoc(), diag::err_destructor_return_type) 1408 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 1409 << SourceRange(D.getIdentifierLoc()); 1410 } 1411 1412 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1413 if (FTI.TypeQuals != 0 && !D.isInvalidType()) { 1414 if (FTI.TypeQuals & QualType::Const) 1415 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1416 << "const" << SourceRange(D.getIdentifierLoc()); 1417 if (FTI.TypeQuals & QualType::Volatile) 1418 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1419 << "volatile" << SourceRange(D.getIdentifierLoc()); 1420 if (FTI.TypeQuals & QualType::Restrict) 1421 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1422 << "restrict" << SourceRange(D.getIdentifierLoc()); 1423 D.setInvalidType(); 1424 } 1425 1426 // Make sure we don't have any parameters. 1427 if (FTI.NumArgs > 0 && !FTIHasSingleVoidArgument(FTI)) { 1428 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params); 1429 1430 // Delete the parameters. 1431 FTI.freeArgs(); 1432 D.setInvalidType(); 1433 } 1434 1435 // Make sure the destructor isn't variadic. 1436 if (FTI.isVariadic) { 1437 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic); 1438 D.setInvalidType(); 1439 } 1440 1441 // Rebuild the function type "R" without any type qualifiers or 1442 // parameters (in case any of the errors above fired) and with 1443 // "void" as the return type, since destructors don't have return 1444 // types. We *always* have to do this, because GetTypeForDeclarator 1445 // will put in a result type of "int" when none was specified. 1446 return Context.getFunctionType(Context.VoidTy, 0, 0, false, 0); 1447} 1448 1449/// CheckConversionDeclarator - Called by ActOnDeclarator to check the 1450/// well-formednes of the conversion function declarator @p D with 1451/// type @p R. If there are any errors in the declarator, this routine 1452/// will emit diagnostics and return true. Otherwise, it will return 1453/// false. Either way, the type @p R will be updated to reflect a 1454/// well-formed type for the conversion operator. 1455void Sema::CheckConversionDeclarator(Declarator &D, QualType &R, 1456 FunctionDecl::StorageClass& SC) { 1457 // C++ [class.conv.fct]p1: 1458 // Neither parameter types nor return type can be specified. The 1459 // type of a conversion function (8.3.5) is “function taking no 1460 // parameter returning conversion-type-id.” 1461 if (SC == FunctionDecl::Static) { 1462 if (!D.isInvalidType()) 1463 Diag(D.getIdentifierLoc(), diag::err_conv_function_not_member) 1464 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1465 << SourceRange(D.getIdentifierLoc()); 1466 D.setInvalidType(); 1467 SC = FunctionDecl::None; 1468 } 1469 if (D.getDeclSpec().hasTypeSpecifier() && !D.isInvalidType()) { 1470 // Conversion functions don't have return types, but the parser will 1471 // happily parse something like: 1472 // 1473 // class X { 1474 // float operator bool(); 1475 // }; 1476 // 1477 // The return type will be changed later anyway. 1478 Diag(D.getIdentifierLoc(), diag::err_conv_function_return_type) 1479 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 1480 << SourceRange(D.getIdentifierLoc()); 1481 } 1482 1483 // Make sure we don't have any parameters. 1484 if (R->getAsFunctionProtoType()->getNumArgs() > 0) { 1485 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params); 1486 1487 // Delete the parameters. 1488 D.getTypeObject(0).Fun.freeArgs(); 1489 D.setInvalidType(); 1490 } 1491 1492 // Make sure the conversion function isn't variadic. 1493 if (R->getAsFunctionProtoType()->isVariadic() && !D.isInvalidType()) { 1494 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic); 1495 D.setInvalidType(); 1496 } 1497 1498 // C++ [class.conv.fct]p4: 1499 // The conversion-type-id shall not represent a function type nor 1500 // an array type. 1501 QualType ConvType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1502 if (ConvType->isArrayType()) { 1503 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array); 1504 ConvType = Context.getPointerType(ConvType); 1505 D.setInvalidType(); 1506 } else if (ConvType->isFunctionType()) { 1507 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function); 1508 ConvType = Context.getPointerType(ConvType); 1509 D.setInvalidType(); 1510 } 1511 1512 // Rebuild the function type "R" without any parameters (in case any 1513 // of the errors above fired) and with the conversion type as the 1514 // return type. 1515 R = Context.getFunctionType(ConvType, 0, 0, false, 1516 R->getAsFunctionProtoType()->getTypeQuals()); 1517 1518 // C++0x explicit conversion operators. 1519 if (D.getDeclSpec().isExplicitSpecified() && !getLangOptions().CPlusPlus0x) 1520 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1521 diag::warn_explicit_conversion_functions) 1522 << SourceRange(D.getDeclSpec().getExplicitSpecLoc()); 1523} 1524 1525/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete 1526/// the declaration of the given C++ conversion function. This routine 1527/// is responsible for recording the conversion function in the C++ 1528/// class, if possible. 1529Sema::DeclPtrTy Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) { 1530 assert(Conversion && "Expected to receive a conversion function declaration"); 1531 1532 // Set the lexical context of this conversion function 1533 Conversion->setLexicalDeclContext(CurContext); 1534 1535 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Conversion->getDeclContext()); 1536 1537 // Make sure we aren't redeclaring the conversion function. 1538 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType()); 1539 1540 // C++ [class.conv.fct]p1: 1541 // [...] A conversion function is never used to convert a 1542 // (possibly cv-qualified) object to the (possibly cv-qualified) 1543 // same object type (or a reference to it), to a (possibly 1544 // cv-qualified) base class of that type (or a reference to it), 1545 // or to (possibly cv-qualified) void. 1546 // FIXME: Suppress this warning if the conversion function ends up being a 1547 // virtual function that overrides a virtual function in a base class. 1548 QualType ClassType 1549 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl)); 1550 if (const ReferenceType *ConvTypeRef = ConvType->getAsReferenceType()) 1551 ConvType = ConvTypeRef->getPointeeType(); 1552 if (ConvType->isRecordType()) { 1553 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType(); 1554 if (ConvType == ClassType) 1555 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used) 1556 << ClassType; 1557 else if (IsDerivedFrom(ClassType, ConvType)) 1558 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used) 1559 << ClassType << ConvType; 1560 } else if (ConvType->isVoidType()) { 1561 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used) 1562 << ClassType << ConvType; 1563 } 1564 1565 if (Conversion->getPreviousDeclaration()) { 1566 OverloadedFunctionDecl *Conversions = ClassDecl->getConversionFunctions(); 1567 for (OverloadedFunctionDecl::function_iterator 1568 Conv = Conversions->function_begin(), 1569 ConvEnd = Conversions->function_end(); 1570 Conv != ConvEnd; ++Conv) { 1571 if (*Conv == Conversion->getPreviousDeclaration()) { 1572 *Conv = Conversion; 1573 return DeclPtrTy::make(Conversion); 1574 } 1575 } 1576 assert(Conversion->isInvalidDecl() && "Conversion should not get here."); 1577 } else 1578 ClassDecl->addConversionFunction(Context, Conversion); 1579 1580 return DeclPtrTy::make(Conversion); 1581} 1582 1583//===----------------------------------------------------------------------===// 1584// Namespace Handling 1585//===----------------------------------------------------------------------===// 1586 1587/// ActOnStartNamespaceDef - This is called at the start of a namespace 1588/// definition. 1589Sema::DeclPtrTy Sema::ActOnStartNamespaceDef(Scope *NamespcScope, 1590 SourceLocation IdentLoc, 1591 IdentifierInfo *II, 1592 SourceLocation LBrace) { 1593 NamespaceDecl *Namespc = 1594 NamespaceDecl::Create(Context, CurContext, IdentLoc, II); 1595 Namespc->setLBracLoc(LBrace); 1596 1597 Scope *DeclRegionScope = NamespcScope->getParent(); 1598 1599 if (II) { 1600 // C++ [namespace.def]p2: 1601 // The identifier in an original-namespace-definition shall not have been 1602 // previously defined in the declarative region in which the 1603 // original-namespace-definition appears. The identifier in an 1604 // original-namespace-definition is the name of the namespace. Subsequently 1605 // in that declarative region, it is treated as an original-namespace-name. 1606 1607 NamedDecl *PrevDecl = LookupName(DeclRegionScope, II, LookupOrdinaryName, 1608 true); 1609 1610 if (NamespaceDecl *OrigNS = dyn_cast_or_null<NamespaceDecl>(PrevDecl)) { 1611 // This is an extended namespace definition. 1612 // Attach this namespace decl to the chain of extended namespace 1613 // definitions. 1614 OrigNS->setNextNamespace(Namespc); 1615 Namespc->setOriginalNamespace(OrigNS->getOriginalNamespace()); 1616 1617 // Remove the previous declaration from the scope. 1618 if (DeclRegionScope->isDeclScope(DeclPtrTy::make(OrigNS))) { 1619 IdResolver.RemoveDecl(OrigNS); 1620 DeclRegionScope->RemoveDecl(DeclPtrTy::make(OrigNS)); 1621 } 1622 } else if (PrevDecl) { 1623 // This is an invalid name redefinition. 1624 Diag(Namespc->getLocation(), diag::err_redefinition_different_kind) 1625 << Namespc->getDeclName(); 1626 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 1627 Namespc->setInvalidDecl(); 1628 // Continue on to push Namespc as current DeclContext and return it. 1629 } 1630 1631 PushOnScopeChains(Namespc, DeclRegionScope); 1632 } else { 1633 // FIXME: Handle anonymous namespaces 1634 } 1635 1636 // Although we could have an invalid decl (i.e. the namespace name is a 1637 // redefinition), push it as current DeclContext and try to continue parsing. 1638 // FIXME: We should be able to push Namespc here, so that the each DeclContext 1639 // for the namespace has the declarations that showed up in that particular 1640 // namespace definition. 1641 PushDeclContext(NamespcScope, Namespc); 1642 return DeclPtrTy::make(Namespc); 1643} 1644 1645/// ActOnFinishNamespaceDef - This callback is called after a namespace is 1646/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. 1647void Sema::ActOnFinishNamespaceDef(DeclPtrTy D, SourceLocation RBrace) { 1648 Decl *Dcl = D.getAs<Decl>(); 1649 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); 1650 assert(Namespc && "Invalid parameter, expected NamespaceDecl"); 1651 Namespc->setRBracLoc(RBrace); 1652 PopDeclContext(); 1653} 1654 1655Sema::DeclPtrTy Sema::ActOnUsingDirective(Scope *S, 1656 SourceLocation UsingLoc, 1657 SourceLocation NamespcLoc, 1658 const CXXScopeSpec &SS, 1659 SourceLocation IdentLoc, 1660 IdentifierInfo *NamespcName, 1661 AttributeList *AttrList) { 1662 assert(!SS.isInvalid() && "Invalid CXXScopeSpec."); 1663 assert(NamespcName && "Invalid NamespcName."); 1664 assert(IdentLoc.isValid() && "Invalid NamespceName location."); 1665 assert(S->getFlags() & Scope::DeclScope && "Invalid Scope."); 1666 1667 UsingDirectiveDecl *UDir = 0; 1668 1669 // Lookup namespace name. 1670 LookupResult R = LookupParsedName(S, &SS, NamespcName, 1671 LookupNamespaceName, false); 1672 if (R.isAmbiguous()) { 1673 DiagnoseAmbiguousLookup(R, NamespcName, IdentLoc); 1674 return DeclPtrTy(); 1675 } 1676 if (NamedDecl *NS = R) { 1677 assert(isa<NamespaceDecl>(NS) && "expected namespace decl"); 1678 // C++ [namespace.udir]p1: 1679 // A using-directive specifies that the names in the nominated 1680 // namespace can be used in the scope in which the 1681 // using-directive appears after the using-directive. During 1682 // unqualified name lookup (3.4.1), the names appear as if they 1683 // were declared in the nearest enclosing namespace which 1684 // contains both the using-directive and the nominated 1685 // namespace. [Note: in this context, “contains” means “contains 1686 // directly or indirectly”. ] 1687 1688 // Find enclosing context containing both using-directive and 1689 // nominated namespace. 1690 DeclContext *CommonAncestor = cast<DeclContext>(NS); 1691 while (CommonAncestor && !CommonAncestor->Encloses(CurContext)) 1692 CommonAncestor = CommonAncestor->getParent(); 1693 1694 UDir = UsingDirectiveDecl::Create(Context, CurContext, UsingLoc, 1695 NamespcLoc, IdentLoc, 1696 cast<NamespaceDecl>(NS), 1697 CommonAncestor); 1698 PushUsingDirective(S, UDir); 1699 } else { 1700 Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange(); 1701 } 1702 1703 // FIXME: We ignore attributes for now. 1704 delete AttrList; 1705 return DeclPtrTy::make(UDir); 1706} 1707 1708void Sema::PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir) { 1709 // If scope has associated entity, then using directive is at namespace 1710 // or translation unit scope. We add UsingDirectiveDecls, into 1711 // it's lookup structure. 1712 if (DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity())) 1713 Ctx->addDecl(Context, UDir); 1714 else 1715 // Otherwise it is block-sope. using-directives will affect lookup 1716 // only to the end of scope. 1717 S->PushUsingDirective(DeclPtrTy::make(UDir)); 1718} 1719 1720/// getNamespaceDecl - Returns the namespace a decl represents. If the decl 1721/// is a namespace alias, returns the namespace it points to. 1722static inline NamespaceDecl *getNamespaceDecl(NamedDecl *D) { 1723 if (NamespaceAliasDecl *AD = dyn_cast_or_null<NamespaceAliasDecl>(D)) 1724 return AD->getNamespace(); 1725 return dyn_cast_or_null<NamespaceDecl>(D); 1726} 1727 1728Sema::DeclPtrTy Sema::ActOnNamespaceAliasDef(Scope *S, 1729 SourceLocation NamespaceLoc, 1730 SourceLocation AliasLoc, 1731 IdentifierInfo *Alias, 1732 const CXXScopeSpec &SS, 1733 SourceLocation IdentLoc, 1734 IdentifierInfo *Ident) { 1735 1736 // Lookup the namespace name. 1737 LookupResult R = LookupParsedName(S, &SS, Ident, LookupNamespaceName, false); 1738 1739 // Check if we have a previous declaration with the same name. 1740 if (NamedDecl *PrevDecl = LookupName(S, Alias, LookupOrdinaryName, true)) { 1741 if (NamespaceAliasDecl *AD = dyn_cast<NamespaceAliasDecl>(PrevDecl)) { 1742 // We already have an alias with the same name that points to the same 1743 // namespace, so don't create a new one. 1744 if (!R.isAmbiguous() && AD->getNamespace() == getNamespaceDecl(R)) 1745 return DeclPtrTy(); 1746 } 1747 1748 unsigned DiagID = isa<NamespaceDecl>(PrevDecl) ? diag::err_redefinition : 1749 diag::err_redefinition_different_kind; 1750 Diag(AliasLoc, DiagID) << Alias; 1751 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 1752 return DeclPtrTy(); 1753 } 1754 1755 if (R.isAmbiguous()) { 1756 DiagnoseAmbiguousLookup(R, Ident, IdentLoc); 1757 return DeclPtrTy(); 1758 } 1759 1760 if (!R) { 1761 Diag(NamespaceLoc, diag::err_expected_namespace_name) << SS.getRange(); 1762 return DeclPtrTy(); 1763 } 1764 1765 NamespaceAliasDecl *AliasDecl = 1766 NamespaceAliasDecl::Create(Context, CurContext, NamespaceLoc, AliasLoc, Alias, 1767 IdentLoc, R); 1768 1769 CurContext->addDecl(Context, AliasDecl); 1770 return DeclPtrTy::make(AliasDecl); 1771} 1772 1773void Sema::InitializeVarWithConstructor(VarDecl *VD, 1774 CXXConstructorDecl *Constructor, 1775 QualType DeclInitType, 1776 Expr **Exprs, unsigned NumExprs) { 1777 Expr *Temp = CXXConstructExpr::Create(Context, VD, DeclInitType, Constructor, 1778 false, Exprs, NumExprs); 1779 VD->setInit(Temp); 1780} 1781 1782/// AddCXXDirectInitializerToDecl - This action is called immediately after 1783/// ActOnDeclarator, when a C++ direct initializer is present. 1784/// e.g: "int x(1);" 1785void Sema::AddCXXDirectInitializerToDecl(DeclPtrTy Dcl, 1786 SourceLocation LParenLoc, 1787 MultiExprArg Exprs, 1788 SourceLocation *CommaLocs, 1789 SourceLocation RParenLoc) { 1790 unsigned NumExprs = Exprs.size(); 1791 assert(NumExprs != 0 && Exprs.get() && "missing expressions"); 1792 Decl *RealDecl = Dcl.getAs<Decl>(); 1793 1794 // If there is no declaration, there was an error parsing it. Just ignore 1795 // the initializer. 1796 if (RealDecl == 0) 1797 return; 1798 1799 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1800 if (!VDecl) { 1801 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 1802 RealDecl->setInvalidDecl(); 1803 return; 1804 } 1805 1806 // FIXME: Need to handle dependent types and expressions here. 1807 1808 // We will treat direct-initialization as a copy-initialization: 1809 // int x(1); -as-> int x = 1; 1810 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); 1811 // 1812 // Clients that want to distinguish between the two forms, can check for 1813 // direct initializer using VarDecl::hasCXXDirectInitializer(). 1814 // A major benefit is that clients that don't particularly care about which 1815 // exactly form was it (like the CodeGen) can handle both cases without 1816 // special case code. 1817 1818 // C++ 8.5p11: 1819 // The form of initialization (using parentheses or '=') is generally 1820 // insignificant, but does matter when the entity being initialized has a 1821 // class type. 1822 QualType DeclInitType = VDecl->getType(); 1823 if (const ArrayType *Array = Context.getAsArrayType(DeclInitType)) 1824 DeclInitType = Array->getElementType(); 1825 1826 // FIXME: This isn't the right place to complete the type. 1827 if (RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 1828 diag::err_typecheck_decl_incomplete_type)) { 1829 VDecl->setInvalidDecl(); 1830 return; 1831 } 1832 1833 if (VDecl->getType()->isRecordType()) { 1834 CXXConstructorDecl *Constructor 1835 = PerformInitializationByConstructor(DeclInitType, 1836 (Expr **)Exprs.get(), NumExprs, 1837 VDecl->getLocation(), 1838 SourceRange(VDecl->getLocation(), 1839 RParenLoc), 1840 VDecl->getDeclName(), 1841 IK_Direct); 1842 if (!Constructor) 1843 RealDecl->setInvalidDecl(); 1844 else { 1845 VDecl->setCXXDirectInitializer(true); 1846 InitializeVarWithConstructor(VDecl, Constructor, DeclInitType, 1847 (Expr**)Exprs.release(), NumExprs); 1848 } 1849 return; 1850 } 1851 1852 if (NumExprs > 1) { 1853 Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg) 1854 << SourceRange(VDecl->getLocation(), RParenLoc); 1855 RealDecl->setInvalidDecl(); 1856 return; 1857 } 1858 1859 // Let clients know that initialization was done with a direct initializer. 1860 VDecl->setCXXDirectInitializer(true); 1861 1862 assert(NumExprs == 1 && "Expected 1 expression"); 1863 // Set the init expression, handles conversions. 1864 AddInitializerToDecl(Dcl, ExprArg(*this, Exprs.release()[0]), 1865 /*DirectInit=*/true); 1866} 1867 1868/// PerformInitializationByConstructor - Perform initialization by 1869/// constructor (C++ [dcl.init]p14), which may occur as part of 1870/// direct-initialization or copy-initialization. We are initializing 1871/// an object of type @p ClassType with the given arguments @p 1872/// Args. @p Loc is the location in the source code where the 1873/// initializer occurs (e.g., a declaration, member initializer, 1874/// functional cast, etc.) while @p Range covers the whole 1875/// initialization. @p InitEntity is the entity being initialized, 1876/// which may by the name of a declaration or a type. @p Kind is the 1877/// kind of initialization we're performing, which affects whether 1878/// explicit constructors will be considered. When successful, returns 1879/// the constructor that will be used to perform the initialization; 1880/// when the initialization fails, emits a diagnostic and returns 1881/// null. 1882CXXConstructorDecl * 1883Sema::PerformInitializationByConstructor(QualType ClassType, 1884 Expr **Args, unsigned NumArgs, 1885 SourceLocation Loc, SourceRange Range, 1886 DeclarationName InitEntity, 1887 InitializationKind Kind) { 1888 const RecordType *ClassRec = ClassType->getAsRecordType(); 1889 assert(ClassRec && "Can only initialize a class type here"); 1890 1891 // C++ [dcl.init]p14: 1892 // 1893 // If the initialization is direct-initialization, or if it is 1894 // copy-initialization where the cv-unqualified version of the 1895 // source type is the same class as, or a derived class of, the 1896 // class of the destination, constructors are considered. The 1897 // applicable constructors are enumerated (13.3.1.3), and the 1898 // best one is chosen through overload resolution (13.3). The 1899 // constructor so selected is called to initialize the object, 1900 // with the initializer expression(s) as its argument(s). If no 1901 // constructor applies, or the overload resolution is ambiguous, 1902 // the initialization is ill-formed. 1903 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1904 OverloadCandidateSet CandidateSet; 1905 1906 // Add constructors to the overload set. 1907 DeclarationName ConstructorName 1908 = Context.DeclarationNames.getCXXConstructorName( 1909 Context.getCanonicalType(ClassType.getUnqualifiedType())); 1910 DeclContext::lookup_const_iterator Con, ConEnd; 1911 for (llvm::tie(Con, ConEnd) = ClassDecl->lookup(Context, ConstructorName); 1912 Con != ConEnd; ++Con) { 1913 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 1914 if ((Kind == IK_Direct) || 1915 (Kind == IK_Copy && Constructor->isConvertingConstructor()) || 1916 (Kind == IK_Default && Constructor->isDefaultConstructor())) 1917 AddOverloadCandidate(Constructor, Args, NumArgs, CandidateSet); 1918 } 1919 1920 // FIXME: When we decide not to synthesize the implicitly-declared 1921 // constructors, we'll need to make them appear here. 1922 1923 OverloadCandidateSet::iterator Best; 1924 switch (BestViableFunction(CandidateSet, Best)) { 1925 case OR_Success: 1926 // We found a constructor. Return it. 1927 return cast<CXXConstructorDecl>(Best->Function); 1928 1929 case OR_No_Viable_Function: 1930 if (InitEntity) 1931 Diag(Loc, diag::err_ovl_no_viable_function_in_init) 1932 << InitEntity << Range; 1933 else 1934 Diag(Loc, diag::err_ovl_no_viable_function_in_init) 1935 << ClassType << Range; 1936 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1937 return 0; 1938 1939 case OR_Ambiguous: 1940 if (InitEntity) 1941 Diag(Loc, diag::err_ovl_ambiguous_init) << InitEntity << Range; 1942 else 1943 Diag(Loc, diag::err_ovl_ambiguous_init) << ClassType << Range; 1944 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1945 return 0; 1946 1947 case OR_Deleted: 1948 if (InitEntity) 1949 Diag(Loc, diag::err_ovl_deleted_init) 1950 << Best->Function->isDeleted() 1951 << InitEntity << Range; 1952 else 1953 Diag(Loc, diag::err_ovl_deleted_init) 1954 << Best->Function->isDeleted() 1955 << InitEntity << Range; 1956 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1957 return 0; 1958 } 1959 1960 return 0; 1961} 1962 1963/// CompareReferenceRelationship - Compare the two types T1 and T2 to 1964/// determine whether they are reference-related, 1965/// reference-compatible, reference-compatible with added 1966/// qualification, or incompatible, for use in C++ initialization by 1967/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 1968/// type, and the first type (T1) is the pointee type of the reference 1969/// type being initialized. 1970Sema::ReferenceCompareResult 1971Sema::CompareReferenceRelationship(QualType T1, QualType T2, 1972 bool& DerivedToBase) { 1973 assert(!T1->isReferenceType() && 1974 "T1 must be the pointee type of the reference type"); 1975 assert(!T2->isReferenceType() && "T2 cannot be a reference type"); 1976 1977 T1 = Context.getCanonicalType(T1); 1978 T2 = Context.getCanonicalType(T2); 1979 QualType UnqualT1 = T1.getUnqualifiedType(); 1980 QualType UnqualT2 = T2.getUnqualifiedType(); 1981 1982 // C++ [dcl.init.ref]p4: 1983 // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is 1984 // reference-related to “cv2 T2” if T1 is the same type as T2, or 1985 // T1 is a base class of T2. 1986 if (UnqualT1 == UnqualT2) 1987 DerivedToBase = false; 1988 else if (IsDerivedFrom(UnqualT2, UnqualT1)) 1989 DerivedToBase = true; 1990 else 1991 return Ref_Incompatible; 1992 1993 // At this point, we know that T1 and T2 are reference-related (at 1994 // least). 1995 1996 // C++ [dcl.init.ref]p4: 1997 // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is 1998 // reference-related to T2 and cv1 is the same cv-qualification 1999 // as, or greater cv-qualification than, cv2. For purposes of 2000 // overload resolution, cases for which cv1 is greater 2001 // cv-qualification than cv2 are identified as 2002 // reference-compatible with added qualification (see 13.3.3.2). 2003 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 2004 return Ref_Compatible; 2005 else if (T1.isMoreQualifiedThan(T2)) 2006 return Ref_Compatible_With_Added_Qualification; 2007 else 2008 return Ref_Related; 2009} 2010 2011/// CheckReferenceInit - Check the initialization of a reference 2012/// variable with the given initializer (C++ [dcl.init.ref]). Init is 2013/// the initializer (either a simple initializer or an initializer 2014/// list), and DeclType is the type of the declaration. When ICS is 2015/// non-null, this routine will compute the implicit conversion 2016/// sequence according to C++ [over.ics.ref] and will not produce any 2017/// diagnostics; when ICS is null, it will emit diagnostics when any 2018/// errors are found. Either way, a return value of true indicates 2019/// that there was a failure, a return value of false indicates that 2020/// the reference initialization succeeded. 2021/// 2022/// When @p SuppressUserConversions, user-defined conversions are 2023/// suppressed. 2024/// When @p AllowExplicit, we also permit explicit user-defined 2025/// conversion functions. 2026/// When @p ForceRValue, we unconditionally treat the initializer as an rvalue. 2027bool 2028Sema::CheckReferenceInit(Expr *&Init, QualType DeclType, 2029 ImplicitConversionSequence *ICS, 2030 bool SuppressUserConversions, 2031 bool AllowExplicit, bool ForceRValue) { 2032 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 2033 2034 QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); 2035 QualType T2 = Init->getType(); 2036 2037 // If the initializer is the address of an overloaded function, try 2038 // to resolve the overloaded function. If all goes well, T2 is the 2039 // type of the resulting function. 2040 if (Context.getCanonicalType(T2) == Context.OverloadTy) { 2041 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Init, DeclType, 2042 ICS != 0); 2043 if (Fn) { 2044 // Since we're performing this reference-initialization for 2045 // real, update the initializer with the resulting function. 2046 if (!ICS) { 2047 if (DiagnoseUseOfDecl(Fn, Init->getSourceRange().getBegin())) 2048 return true; 2049 2050 FixOverloadedFunctionReference(Init, Fn); 2051 } 2052 2053 T2 = Fn->getType(); 2054 } 2055 } 2056 2057 // Compute some basic properties of the types and the initializer. 2058 bool isRValRef = DeclType->isRValueReferenceType(); 2059 bool DerivedToBase = false; 2060 Expr::isLvalueResult InitLvalue = ForceRValue ? Expr::LV_InvalidExpression : 2061 Init->isLvalue(Context); 2062 ReferenceCompareResult RefRelationship 2063 = CompareReferenceRelationship(T1, T2, DerivedToBase); 2064 2065 // Most paths end in a failed conversion. 2066 if (ICS) 2067 ICS->ConversionKind = ImplicitConversionSequence::BadConversion; 2068 2069 // C++ [dcl.init.ref]p5: 2070 // A reference to type “cv1 T1” is initialized by an expression 2071 // of type “cv2 T2” as follows: 2072 2073 // -- If the initializer expression 2074 2075 // Rvalue references cannot bind to lvalues (N2812). 2076 // There is absolutely no situation where they can. In particular, note that 2077 // this is ill-formed, even if B has a user-defined conversion to A&&: 2078 // B b; 2079 // A&& r = b; 2080 if (isRValRef && InitLvalue == Expr::LV_Valid) { 2081 if (!ICS) 2082 Diag(Init->getSourceRange().getBegin(), diag::err_lvalue_to_rvalue_ref) 2083 << Init->getSourceRange(); 2084 return true; 2085 } 2086 2087 bool BindsDirectly = false; 2088 // -- is an lvalue (but is not a bit-field), and “cv1 T1” is 2089 // reference-compatible with “cv2 T2,” or 2090 // 2091 // Note that the bit-field check is skipped if we are just computing 2092 // the implicit conversion sequence (C++ [over.best.ics]p2). 2093 if (InitLvalue == Expr::LV_Valid && (ICS || !Init->getBitField()) && 2094 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 2095 BindsDirectly = true; 2096 2097 if (ICS) { 2098 // C++ [over.ics.ref]p1: 2099 // When a parameter of reference type binds directly (8.5.3) 2100 // to an argument expression, the implicit conversion sequence 2101 // is the identity conversion, unless the argument expression 2102 // has a type that is a derived class of the parameter type, 2103 // in which case the implicit conversion sequence is a 2104 // derived-to-base Conversion (13.3.3.1). 2105 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 2106 ICS->Standard.First = ICK_Identity; 2107 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 2108 ICS->Standard.Third = ICK_Identity; 2109 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 2110 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 2111 ICS->Standard.ReferenceBinding = true; 2112 ICS->Standard.DirectBinding = true; 2113 ICS->Standard.RRefBinding = false; 2114 ICS->Standard.CopyConstructor = 0; 2115 2116 // Nothing more to do: the inaccessibility/ambiguity check for 2117 // derived-to-base conversions is suppressed when we're 2118 // computing the implicit conversion sequence (C++ 2119 // [over.best.ics]p2). 2120 return false; 2121 } else { 2122 // Perform the conversion. 2123 // FIXME: Binding to a subobject of the lvalue is going to require more 2124 // AST annotation than this. 2125 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 2126 } 2127 } 2128 2129 // -- has a class type (i.e., T2 is a class type) and can be 2130 // implicitly converted to an lvalue of type “cv3 T3,” 2131 // where “cv1 T1” is reference-compatible with “cv3 T3” 2132 // 92) (this conversion is selected by enumerating the 2133 // applicable conversion functions (13.3.1.6) and choosing 2134 // the best one through overload resolution (13.3)), 2135 if (!isRValRef && !SuppressUserConversions && T2->isRecordType()) { 2136 // FIXME: Look for conversions in base classes! 2137 CXXRecordDecl *T2RecordDecl 2138 = dyn_cast<CXXRecordDecl>(T2->getAsRecordType()->getDecl()); 2139 2140 OverloadCandidateSet CandidateSet; 2141 OverloadedFunctionDecl *Conversions 2142 = T2RecordDecl->getConversionFunctions(); 2143 for (OverloadedFunctionDecl::function_iterator Func 2144 = Conversions->function_begin(); 2145 Func != Conversions->function_end(); ++Func) { 2146 CXXConversionDecl *Conv = cast<CXXConversionDecl>(*Func); 2147 2148 // If the conversion function doesn't return a reference type, 2149 // it can't be considered for this conversion. 2150 if (Conv->getConversionType()->isLValueReferenceType() && 2151 (AllowExplicit || !Conv->isExplicit())) 2152 AddConversionCandidate(Conv, Init, DeclType, CandidateSet); 2153 } 2154 2155 OverloadCandidateSet::iterator Best; 2156 switch (BestViableFunction(CandidateSet, Best)) { 2157 case OR_Success: 2158 // This is a direct binding. 2159 BindsDirectly = true; 2160 2161 if (ICS) { 2162 // C++ [over.ics.ref]p1: 2163 // 2164 // [...] If the parameter binds directly to the result of 2165 // applying a conversion function to the argument 2166 // expression, the implicit conversion sequence is a 2167 // user-defined conversion sequence (13.3.3.1.2), with the 2168 // second standard conversion sequence either an identity 2169 // conversion or, if the conversion function returns an 2170 // entity of a type that is a derived class of the parameter 2171 // type, a derived-to-base Conversion. 2172 ICS->ConversionKind = ImplicitConversionSequence::UserDefinedConversion; 2173 ICS->UserDefined.Before = Best->Conversions[0].Standard; 2174 ICS->UserDefined.After = Best->FinalConversion; 2175 ICS->UserDefined.ConversionFunction = Best->Function; 2176 assert(ICS->UserDefined.After.ReferenceBinding && 2177 ICS->UserDefined.After.DirectBinding && 2178 "Expected a direct reference binding!"); 2179 return false; 2180 } else { 2181 // Perform the conversion. 2182 // FIXME: Binding to a subobject of the lvalue is going to require more 2183 // AST annotation than this. 2184 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 2185 } 2186 break; 2187 2188 case OR_Ambiguous: 2189 assert(false && "Ambiguous reference binding conversions not implemented."); 2190 return true; 2191 2192 case OR_No_Viable_Function: 2193 case OR_Deleted: 2194 // There was no suitable conversion, or we found a deleted 2195 // conversion; continue with other checks. 2196 break; 2197 } 2198 } 2199 2200 if (BindsDirectly) { 2201 // C++ [dcl.init.ref]p4: 2202 // [...] In all cases where the reference-related or 2203 // reference-compatible relationship of two types is used to 2204 // establish the validity of a reference binding, and T1 is a 2205 // base class of T2, a program that necessitates such a binding 2206 // is ill-formed if T1 is an inaccessible (clause 11) or 2207 // ambiguous (10.2) base class of T2. 2208 // 2209 // Note that we only check this condition when we're allowed to 2210 // complain about errors, because we should not be checking for 2211 // ambiguity (or inaccessibility) unless the reference binding 2212 // actually happens. 2213 if (DerivedToBase) 2214 return CheckDerivedToBaseConversion(T2, T1, 2215 Init->getSourceRange().getBegin(), 2216 Init->getSourceRange()); 2217 else 2218 return false; 2219 } 2220 2221 // -- Otherwise, the reference shall be to a non-volatile const 2222 // type (i.e., cv1 shall be const), or the reference shall be an 2223 // rvalue reference and the initializer expression shall be an rvalue. 2224 if (!isRValRef && T1.getCVRQualifiers() != QualType::Const) { 2225 if (!ICS) 2226 Diag(Init->getSourceRange().getBegin(), 2227 diag::err_not_reference_to_const_init) 2228 << T1 << (InitLvalue != Expr::LV_Valid? "temporary" : "value") 2229 << T2 << Init->getSourceRange(); 2230 return true; 2231 } 2232 2233 // -- If the initializer expression is an rvalue, with T2 a 2234 // class type, and “cv1 T1” is reference-compatible with 2235 // “cv2 T2,” the reference is bound in one of the 2236 // following ways (the choice is implementation-defined): 2237 // 2238 // -- The reference is bound to the object represented by 2239 // the rvalue (see 3.10) or to a sub-object within that 2240 // object. 2241 // 2242 // -- A temporary of type “cv1 T2” [sic] is created, and 2243 // a constructor is called to copy the entire rvalue 2244 // object into the temporary. The reference is bound to 2245 // the temporary or to a sub-object within the 2246 // temporary. 2247 // 2248 // The constructor that would be used to make the copy 2249 // shall be callable whether or not the copy is actually 2250 // done. 2251 // 2252 // Note that C++0x [dcl.init.ref]p5 takes away this implementation 2253 // freedom, so we will always take the first option and never build 2254 // a temporary in this case. FIXME: We will, however, have to check 2255 // for the presence of a copy constructor in C++98/03 mode. 2256 if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && 2257 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 2258 if (ICS) { 2259 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 2260 ICS->Standard.First = ICK_Identity; 2261 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 2262 ICS->Standard.Third = ICK_Identity; 2263 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 2264 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 2265 ICS->Standard.ReferenceBinding = true; 2266 ICS->Standard.DirectBinding = false; 2267 ICS->Standard.RRefBinding = isRValRef; 2268 ICS->Standard.CopyConstructor = 0; 2269 } else { 2270 // FIXME: Binding to a subobject of the rvalue is going to require more 2271 // AST annotation than this. 2272 ImpCastExprToType(Init, T1, /*isLvalue=*/false); 2273 } 2274 return false; 2275 } 2276 2277 // -- Otherwise, a temporary of type “cv1 T1” is created and 2278 // initialized from the initializer expression using the 2279 // rules for a non-reference copy initialization (8.5). The 2280 // reference is then bound to the temporary. If T1 is 2281 // reference-related to T2, cv1 must be the same 2282 // cv-qualification as, or greater cv-qualification than, 2283 // cv2; otherwise, the program is ill-formed. 2284 if (RefRelationship == Ref_Related) { 2285 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 2286 // we would be reference-compatible or reference-compatible with 2287 // added qualification. But that wasn't the case, so the reference 2288 // initialization fails. 2289 if (!ICS) 2290 Diag(Init->getSourceRange().getBegin(), 2291 diag::err_reference_init_drops_quals) 2292 << T1 << (InitLvalue != Expr::LV_Valid? "temporary" : "value") 2293 << T2 << Init->getSourceRange(); 2294 return true; 2295 } 2296 2297 // If at least one of the types is a class type, the types are not 2298 // related, and we aren't allowed any user conversions, the 2299 // reference binding fails. This case is important for breaking 2300 // recursion, since TryImplicitConversion below will attempt to 2301 // create a temporary through the use of a copy constructor. 2302 if (SuppressUserConversions && RefRelationship == Ref_Incompatible && 2303 (T1->isRecordType() || T2->isRecordType())) { 2304 if (!ICS) 2305 Diag(Init->getSourceRange().getBegin(), 2306 diag::err_typecheck_convert_incompatible) 2307 << DeclType << Init->getType() << "initializing" << Init->getSourceRange(); 2308 return true; 2309 } 2310 2311 // Actually try to convert the initializer to T1. 2312 if (ICS) { 2313 // C++ [over.ics.ref]p2: 2314 // 2315 // When a parameter of reference type is not bound directly to 2316 // an argument expression, the conversion sequence is the one 2317 // required to convert the argument expression to the 2318 // underlying type of the reference according to 2319 // 13.3.3.1. Conceptually, this conversion sequence corresponds 2320 // to copy-initializing a temporary of the underlying type with 2321 // the argument expression. Any difference in top-level 2322 // cv-qualification is subsumed by the initialization itself 2323 // and does not constitute a conversion. 2324 *ICS = TryImplicitConversion(Init, T1, SuppressUserConversions); 2325 // Of course, that's still a reference binding. 2326 if (ICS->ConversionKind == ImplicitConversionSequence::StandardConversion) { 2327 ICS->Standard.ReferenceBinding = true; 2328 ICS->Standard.RRefBinding = isRValRef; 2329 } else if(ICS->ConversionKind == 2330 ImplicitConversionSequence::UserDefinedConversion) { 2331 ICS->UserDefined.After.ReferenceBinding = true; 2332 ICS->UserDefined.After.RRefBinding = isRValRef; 2333 } 2334 return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; 2335 } else { 2336 return PerformImplicitConversion(Init, T1, "initializing"); 2337 } 2338} 2339 2340/// CheckOverloadedOperatorDeclaration - Check whether the declaration 2341/// of this overloaded operator is well-formed. If so, returns false; 2342/// otherwise, emits appropriate diagnostics and returns true. 2343bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) { 2344 assert(FnDecl && FnDecl->isOverloadedOperator() && 2345 "Expected an overloaded operator declaration"); 2346 2347 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator(); 2348 2349 // C++ [over.oper]p5: 2350 // The allocation and deallocation functions, operator new, 2351 // operator new[], operator delete and operator delete[], are 2352 // described completely in 3.7.3. The attributes and restrictions 2353 // found in the rest of this subclause do not apply to them unless 2354 // explicitly stated in 3.7.3. 2355 // FIXME: Write a separate routine for checking this. For now, just allow it. 2356 if (Op == OO_New || Op == OO_Array_New || 2357 Op == OO_Delete || Op == OO_Array_Delete) 2358 return false; 2359 2360 // C++ [over.oper]p6: 2361 // An operator function shall either be a non-static member 2362 // function or be a non-member function and have at least one 2363 // parameter whose type is a class, a reference to a class, an 2364 // enumeration, or a reference to an enumeration. 2365 if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl)) { 2366 if (MethodDecl->isStatic()) 2367 return Diag(FnDecl->getLocation(), 2368 diag::err_operator_overload_static) << FnDecl->getDeclName(); 2369 } else { 2370 bool ClassOrEnumParam = false; 2371 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(), 2372 ParamEnd = FnDecl->param_end(); 2373 Param != ParamEnd; ++Param) { 2374 QualType ParamType = (*Param)->getType().getNonReferenceType(); 2375 if (ParamType->isRecordType() || ParamType->isEnumeralType()) { 2376 ClassOrEnumParam = true; 2377 break; 2378 } 2379 } 2380 2381 if (!ClassOrEnumParam) 2382 return Diag(FnDecl->getLocation(), 2383 diag::err_operator_overload_needs_class_or_enum) 2384 << FnDecl->getDeclName(); 2385 } 2386 2387 // C++ [over.oper]p8: 2388 // An operator function cannot have default arguments (8.3.6), 2389 // except where explicitly stated below. 2390 // 2391 // Only the function-call operator allows default arguments 2392 // (C++ [over.call]p1). 2393 if (Op != OO_Call) { 2394 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 2395 Param != FnDecl->param_end(); ++Param) { 2396 if ((*Param)->hasUnparsedDefaultArg()) 2397 return Diag((*Param)->getLocation(), 2398 diag::err_operator_overload_default_arg) 2399 << FnDecl->getDeclName(); 2400 else if (Expr *DefArg = (*Param)->getDefaultArg()) 2401 return Diag((*Param)->getLocation(), 2402 diag::err_operator_overload_default_arg) 2403 << FnDecl->getDeclName() << DefArg->getSourceRange(); 2404 } 2405 } 2406 2407 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = { 2408 { false, false, false } 2409#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \ 2410 , { Unary, Binary, MemberOnly } 2411#include "clang/Basic/OperatorKinds.def" 2412 }; 2413 2414 bool CanBeUnaryOperator = OperatorUses[Op][0]; 2415 bool CanBeBinaryOperator = OperatorUses[Op][1]; 2416 bool MustBeMemberOperator = OperatorUses[Op][2]; 2417 2418 // C++ [over.oper]p8: 2419 // [...] Operator functions cannot have more or fewer parameters 2420 // than the number required for the corresponding operator, as 2421 // described in the rest of this subclause. 2422 unsigned NumParams = FnDecl->getNumParams() 2423 + (isa<CXXMethodDecl>(FnDecl)? 1 : 0); 2424 if (Op != OO_Call && 2425 ((NumParams == 1 && !CanBeUnaryOperator) || 2426 (NumParams == 2 && !CanBeBinaryOperator) || 2427 (NumParams < 1) || (NumParams > 2))) { 2428 // We have the wrong number of parameters. 2429 unsigned ErrorKind; 2430 if (CanBeUnaryOperator && CanBeBinaryOperator) { 2431 ErrorKind = 2; // 2 -> unary or binary. 2432 } else if (CanBeUnaryOperator) { 2433 ErrorKind = 0; // 0 -> unary 2434 } else { 2435 assert(CanBeBinaryOperator && 2436 "All non-call overloaded operators are unary or binary!"); 2437 ErrorKind = 1; // 1 -> binary 2438 } 2439 2440 return Diag(FnDecl->getLocation(), diag::err_operator_overload_must_be) 2441 << FnDecl->getDeclName() << NumParams << ErrorKind; 2442 } 2443 2444 // Overloaded operators other than operator() cannot be variadic. 2445 if (Op != OO_Call && 2446 FnDecl->getType()->getAsFunctionProtoType()->isVariadic()) { 2447 return Diag(FnDecl->getLocation(), diag::err_operator_overload_variadic) 2448 << FnDecl->getDeclName(); 2449 } 2450 2451 // Some operators must be non-static member functions. 2452 if (MustBeMemberOperator && !isa<CXXMethodDecl>(FnDecl)) { 2453 return Diag(FnDecl->getLocation(), 2454 diag::err_operator_overload_must_be_member) 2455 << FnDecl->getDeclName(); 2456 } 2457 2458 // C++ [over.inc]p1: 2459 // The user-defined function called operator++ implements the 2460 // prefix and postfix ++ operator. If this function is a member 2461 // function with no parameters, or a non-member function with one 2462 // parameter of class or enumeration type, it defines the prefix 2463 // increment operator ++ for objects of that type. If the function 2464 // is a member function with one parameter (which shall be of type 2465 // int) or a non-member function with two parameters (the second 2466 // of which shall be of type int), it defines the postfix 2467 // increment operator ++ for objects of that type. 2468 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) { 2469 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1); 2470 bool ParamIsInt = false; 2471 if (const BuiltinType *BT = LastParam->getType()->getAsBuiltinType()) 2472 ParamIsInt = BT->getKind() == BuiltinType::Int; 2473 2474 if (!ParamIsInt) 2475 return Diag(LastParam->getLocation(), 2476 diag::err_operator_overload_post_incdec_must_be_int) 2477 << LastParam->getType() << (Op == OO_MinusMinus); 2478 } 2479 2480 // Notify the class if it got an assignment operator. 2481 if (Op == OO_Equal) { 2482 // Would have returned earlier otherwise. 2483 assert(isa<CXXMethodDecl>(FnDecl) && 2484 "Overloaded = not member, but not filtered."); 2485 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 2486 Method->getParent()->addedAssignmentOperator(Context, Method); 2487 } 2488 2489 return false; 2490} 2491 2492/// ActOnStartLinkageSpecification - Parsed the beginning of a C++ 2493/// linkage specification, including the language and (if present) 2494/// the '{'. ExternLoc is the location of the 'extern', LangLoc is 2495/// the location of the language string literal, which is provided 2496/// by Lang/StrSize. LBraceLoc, if valid, provides the location of 2497/// the '{' brace. Otherwise, this linkage specification does not 2498/// have any braces. 2499Sema::DeclPtrTy Sema::ActOnStartLinkageSpecification(Scope *S, 2500 SourceLocation ExternLoc, 2501 SourceLocation LangLoc, 2502 const char *Lang, 2503 unsigned StrSize, 2504 SourceLocation LBraceLoc) { 2505 LinkageSpecDecl::LanguageIDs Language; 2506 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2507 Language = LinkageSpecDecl::lang_c; 2508 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2509 Language = LinkageSpecDecl::lang_cxx; 2510 else { 2511 Diag(LangLoc, diag::err_bad_language); 2512 return DeclPtrTy(); 2513 } 2514 2515 // FIXME: Add all the various semantics of linkage specifications 2516 2517 LinkageSpecDecl *D = LinkageSpecDecl::Create(Context, CurContext, 2518 LangLoc, Language, 2519 LBraceLoc.isValid()); 2520 CurContext->addDecl(Context, D); 2521 PushDeclContext(S, D); 2522 return DeclPtrTy::make(D); 2523} 2524 2525/// ActOnFinishLinkageSpecification - Completely the definition of 2526/// the C++ linkage specification LinkageSpec. If RBraceLoc is 2527/// valid, it's the position of the closing '}' brace in a linkage 2528/// specification that uses braces. 2529Sema::DeclPtrTy Sema::ActOnFinishLinkageSpecification(Scope *S, 2530 DeclPtrTy LinkageSpec, 2531 SourceLocation RBraceLoc) { 2532 if (LinkageSpec) 2533 PopDeclContext(); 2534 return LinkageSpec; 2535} 2536 2537/// \brief Perform semantic analysis for the variable declaration that 2538/// occurs within a C++ catch clause, returning the newly-created 2539/// variable. 2540VarDecl *Sema::BuildExceptionDeclaration(Scope *S, QualType ExDeclType, 2541 IdentifierInfo *Name, 2542 SourceLocation Loc, 2543 SourceRange Range) { 2544 bool Invalid = false; 2545 2546 // Arrays and functions decay. 2547 if (ExDeclType->isArrayType()) 2548 ExDeclType = Context.getArrayDecayedType(ExDeclType); 2549 else if (ExDeclType->isFunctionType()) 2550 ExDeclType = Context.getPointerType(ExDeclType); 2551 2552 // C++ 15.3p1: The exception-declaration shall not denote an incomplete type. 2553 // The exception-declaration shall not denote a pointer or reference to an 2554 // incomplete type, other than [cv] void*. 2555 // N2844 forbids rvalue references. 2556 if(!ExDeclType->isDependentType() && ExDeclType->isRValueReferenceType()) { 2557 Diag(Loc, diag::err_catch_rvalue_ref) << Range; 2558 Invalid = true; 2559 } 2560 2561 QualType BaseType = ExDeclType; 2562 int Mode = 0; // 0 for direct type, 1 for pointer, 2 for reference 2563 unsigned DK = diag::err_catch_incomplete; 2564 if (const PointerType *Ptr = BaseType->getAsPointerType()) { 2565 BaseType = Ptr->getPointeeType(); 2566 Mode = 1; 2567 DK = diag::err_catch_incomplete_ptr; 2568 } else if(const ReferenceType *Ref = BaseType->getAsReferenceType()) { 2569 // For the purpose of error recovery, we treat rvalue refs like lvalue refs. 2570 BaseType = Ref->getPointeeType(); 2571 Mode = 2; 2572 DK = diag::err_catch_incomplete_ref; 2573 } 2574 if (!Invalid && (Mode == 0 || !BaseType->isVoidType()) && 2575 !BaseType->isDependentType() && RequireCompleteType(Loc, BaseType, DK)) 2576 Invalid = true; 2577 2578 if (!Invalid && !ExDeclType->isDependentType() && 2579 RequireNonAbstractType(Loc, ExDeclType, 2580 diag::err_abstract_type_in_decl, 2581 AbstractVariableType)) 2582 Invalid = true; 2583 2584 // FIXME: Need to test for ability to copy-construct and destroy the 2585 // exception variable. 2586 2587 // FIXME: Need to check for abstract classes. 2588 2589 VarDecl *ExDecl = VarDecl::Create(Context, CurContext, Loc, 2590 Name, ExDeclType, VarDecl::None, 2591 Range.getBegin()); 2592 2593 if (Invalid) 2594 ExDecl->setInvalidDecl(); 2595 2596 return ExDecl; 2597} 2598 2599/// ActOnExceptionDeclarator - Parsed the exception-declarator in a C++ catch 2600/// handler. 2601Sema::DeclPtrTy Sema::ActOnExceptionDeclarator(Scope *S, Declarator &D) { 2602 QualType ExDeclType = GetTypeForDeclarator(D, S); 2603 2604 bool Invalid = D.isInvalidType(); 2605 IdentifierInfo *II = D.getIdentifier(); 2606 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2607 // The scope should be freshly made just for us. There is just no way 2608 // it contains any previous declaration. 2609 assert(!S->isDeclScope(DeclPtrTy::make(PrevDecl))); 2610 if (PrevDecl->isTemplateParameter()) { 2611 // Maybe we will complain about the shadowed template parameter. 2612 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2613 } 2614 } 2615 2616 if (D.getCXXScopeSpec().isSet() && !Invalid) { 2617 Diag(D.getIdentifierLoc(), diag::err_qualified_catch_declarator) 2618 << D.getCXXScopeSpec().getRange(); 2619 Invalid = true; 2620 } 2621 2622 VarDecl *ExDecl = BuildExceptionDeclaration(S, ExDeclType, 2623 D.getIdentifier(), 2624 D.getIdentifierLoc(), 2625 D.getDeclSpec().getSourceRange()); 2626 2627 if (Invalid) 2628 ExDecl->setInvalidDecl(); 2629 2630 // Add the exception declaration into this scope. 2631 if (II) 2632 PushOnScopeChains(ExDecl, S); 2633 else 2634 CurContext->addDecl(Context, ExDecl); 2635 2636 ProcessDeclAttributes(ExDecl, D); 2637 return DeclPtrTy::make(ExDecl); 2638} 2639 2640Sema::DeclPtrTy Sema::ActOnStaticAssertDeclaration(SourceLocation AssertLoc, 2641 ExprArg assertexpr, 2642 ExprArg assertmessageexpr) { 2643 Expr *AssertExpr = (Expr *)assertexpr.get(); 2644 StringLiteral *AssertMessage = 2645 cast<StringLiteral>((Expr *)assertmessageexpr.get()); 2646 2647 if (!AssertExpr->isTypeDependent() && !AssertExpr->isValueDependent()) { 2648 llvm::APSInt Value(32); 2649 if (!AssertExpr->isIntegerConstantExpr(Value, Context)) { 2650 Diag(AssertLoc, diag::err_static_assert_expression_is_not_constant) << 2651 AssertExpr->getSourceRange(); 2652 return DeclPtrTy(); 2653 } 2654 2655 if (Value == 0) { 2656 std::string str(AssertMessage->getStrData(), 2657 AssertMessage->getByteLength()); 2658 Diag(AssertLoc, diag::err_static_assert_failed) 2659 << str << AssertExpr->getSourceRange(); 2660 } 2661 } 2662 2663 assertexpr.release(); 2664 assertmessageexpr.release(); 2665 Decl *Decl = StaticAssertDecl::Create(Context, CurContext, AssertLoc, 2666 AssertExpr, AssertMessage); 2667 2668 CurContext->addDecl(Context, Decl); 2669 return DeclPtrTy::make(Decl); 2670} 2671 2672bool Sema::ActOnFriendDecl(Scope *S, SourceLocation FriendLoc, DeclPtrTy Dcl) { 2673 if (!(S->getFlags() & Scope::ClassScope)) { 2674 Diag(FriendLoc, diag::err_friend_decl_outside_class); 2675 return true; 2676 } 2677 2678 return false; 2679} 2680 2681void Sema::SetDeclDeleted(DeclPtrTy dcl, SourceLocation DelLoc) { 2682 Decl *Dcl = dcl.getAs<Decl>(); 2683 FunctionDecl *Fn = dyn_cast<FunctionDecl>(Dcl); 2684 if (!Fn) { 2685 Diag(DelLoc, diag::err_deleted_non_function); 2686 return; 2687 } 2688 if (const FunctionDecl *Prev = Fn->getPreviousDeclaration()) { 2689 Diag(DelLoc, diag::err_deleted_decl_not_first); 2690 Diag(Prev->getLocation(), diag::note_previous_declaration); 2691 // If the declaration wasn't the first, we delete the function anyway for 2692 // recovery. 2693 } 2694 Fn->setDeleted(); 2695} 2696 2697static void SearchForReturnInStmt(Sema &Self, Stmt *S) { 2698 for (Stmt::child_iterator CI = S->child_begin(), E = S->child_end(); CI != E; 2699 ++CI) { 2700 Stmt *SubStmt = *CI; 2701 if (!SubStmt) 2702 continue; 2703 if (isa<ReturnStmt>(SubStmt)) 2704 Self.Diag(SubStmt->getSourceRange().getBegin(), 2705 diag::err_return_in_constructor_handler); 2706 if (!isa<Expr>(SubStmt)) 2707 SearchForReturnInStmt(Self, SubStmt); 2708 } 2709} 2710 2711void Sema::DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock) { 2712 for (unsigned I = 0, E = TryBlock->getNumHandlers(); I != E; ++I) { 2713 CXXCatchStmt *Handler = TryBlock->getHandler(I); 2714 SearchForReturnInStmt(*this, Handler); 2715 } 2716} 2717 2718bool Sema::CheckOverridingFunctionReturnType(const CXXMethodDecl *New, 2719 const CXXMethodDecl *Old) { 2720 QualType NewTy = New->getType()->getAsFunctionType()->getResultType(); 2721 QualType OldTy = Old->getType()->getAsFunctionType()->getResultType(); 2722 2723 QualType CNewTy = Context.getCanonicalType(NewTy); 2724 QualType COldTy = Context.getCanonicalType(OldTy); 2725 2726 if (CNewTy == COldTy && 2727 CNewTy.getCVRQualifiers() == COldTy.getCVRQualifiers()) 2728 return false; 2729 2730 // Check if the return types are covariant 2731 QualType NewClassTy, OldClassTy; 2732 2733 /// Both types must be pointers or references to classes. 2734 if (PointerType *NewPT = dyn_cast<PointerType>(NewTy)) { 2735 if (PointerType *OldPT = dyn_cast<PointerType>(OldTy)) { 2736 NewClassTy = NewPT->getPointeeType(); 2737 OldClassTy = OldPT->getPointeeType(); 2738 } 2739 } else if (ReferenceType *NewRT = dyn_cast<ReferenceType>(NewTy)) { 2740 if (ReferenceType *OldRT = dyn_cast<ReferenceType>(OldTy)) { 2741 NewClassTy = NewRT->getPointeeType(); 2742 OldClassTy = OldRT->getPointeeType(); 2743 } 2744 } 2745 2746 // The return types aren't either both pointers or references to a class type. 2747 if (NewClassTy.isNull()) { 2748 Diag(New->getLocation(), 2749 diag::err_different_return_type_for_overriding_virtual_function) 2750 << New->getDeclName() << NewTy << OldTy; 2751 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2752 2753 return true; 2754 } 2755 2756 if (NewClassTy.getUnqualifiedType() != OldClassTy.getUnqualifiedType()) { 2757 // Check if the new class derives from the old class. 2758 if (!IsDerivedFrom(NewClassTy, OldClassTy)) { 2759 Diag(New->getLocation(), 2760 diag::err_covariant_return_not_derived) 2761 << New->getDeclName() << NewTy << OldTy; 2762 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2763 return true; 2764 } 2765 2766 // Check if we the conversion from derived to base is valid. 2767 if (CheckDerivedToBaseConversion(NewClassTy, OldClassTy, 2768 diag::err_covariant_return_inaccessible_base, 2769 diag::err_covariant_return_ambiguous_derived_to_base_conv, 2770 // FIXME: Should this point to the return type? 2771 New->getLocation(), SourceRange(), New->getDeclName())) { 2772 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2773 return true; 2774 } 2775 } 2776 2777 // The qualifiers of the return types must be the same. 2778 if (CNewTy.getCVRQualifiers() != COldTy.getCVRQualifiers()) { 2779 Diag(New->getLocation(), 2780 diag::err_covariant_return_type_different_qualifications) 2781 << New->getDeclName() << NewTy << OldTy; 2782 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2783 return true; 2784 }; 2785 2786 2787 // The new class type must have the same or less qualifiers as the old type. 2788 if (NewClassTy.isMoreQualifiedThan(OldClassTy)) { 2789 Diag(New->getLocation(), 2790 diag::err_covariant_return_type_class_type_more_qualified) 2791 << New->getDeclName() << NewTy << OldTy; 2792 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2793 return true; 2794 }; 2795 2796 return false; 2797} 2798