SemaDeclCXX.cpp revision 465226e23a3008bd68973513dda1f9e3cd27dbdd
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 // FIXME: Implicit declarations have exception specifications, which are 1003 // the union of the specifications of the implicitly called functions. 1004 1005 if (!ClassDecl->hasUserDeclaredConstructor()) { 1006 // C++ [class.ctor]p5: 1007 // A default constructor for a class X is a constructor of class X 1008 // that can be called without an argument. If there is no 1009 // user-declared constructor for class X, a default constructor is 1010 // implicitly declared. An implicitly-declared default constructor 1011 // is an inline public member of its class. 1012 DeclarationName Name 1013 = Context.DeclarationNames.getCXXConstructorName(ClassType); 1014 CXXConstructorDecl *DefaultCon = 1015 CXXConstructorDecl::Create(Context, ClassDecl, 1016 ClassDecl->getLocation(), Name, 1017 Context.getFunctionType(Context.VoidTy, 1018 0, 0, false, 0), 1019 /*isExplicit=*/false, 1020 /*isInline=*/true, 1021 /*isImplicitlyDeclared=*/true); 1022 DefaultCon->setAccess(AS_public); 1023 DefaultCon->setImplicit(); 1024 ClassDecl->addDecl(Context, DefaultCon); 1025 1026 // Notify the class that we've added a constructor. 1027 ClassDecl->addedConstructor(Context, DefaultCon); 1028 } 1029 1030 if (!ClassDecl->hasUserDeclaredCopyConstructor()) { 1031 // C++ [class.copy]p4: 1032 // If the class definition does not explicitly declare a copy 1033 // constructor, one is declared implicitly. 1034 1035 // C++ [class.copy]p5: 1036 // The implicitly-declared copy constructor for a class X will 1037 // have the form 1038 // 1039 // X::X(const X&) 1040 // 1041 // if 1042 bool HasConstCopyConstructor = true; 1043 1044 // -- each direct or virtual base class B of X has a copy 1045 // constructor whose first parameter is of type const B& or 1046 // const volatile B&, and 1047 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 1048 HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { 1049 const CXXRecordDecl *BaseClassDecl 1050 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 1051 HasConstCopyConstructor 1052 = BaseClassDecl->hasConstCopyConstructor(Context); 1053 } 1054 1055 // -- for all the nonstatic data members of X that are of a 1056 // class type M (or array thereof), each such class type 1057 // has a copy constructor whose first parameter is of type 1058 // const M& or const volatile M&. 1059 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(Context); 1060 HasConstCopyConstructor && Field != ClassDecl->field_end(Context); 1061 ++Field) { 1062 QualType FieldType = (*Field)->getType(); 1063 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 1064 FieldType = Array->getElementType(); 1065 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 1066 const CXXRecordDecl *FieldClassDecl 1067 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 1068 HasConstCopyConstructor 1069 = FieldClassDecl->hasConstCopyConstructor(Context); 1070 } 1071 } 1072 1073 // Otherwise, the implicitly declared copy constructor will have 1074 // the form 1075 // 1076 // X::X(X&) 1077 QualType ArgType = ClassType; 1078 if (HasConstCopyConstructor) 1079 ArgType = ArgType.withConst(); 1080 ArgType = Context.getLValueReferenceType(ArgType); 1081 1082 // An implicitly-declared copy constructor is an inline public 1083 // member of its class. 1084 DeclarationName Name 1085 = Context.DeclarationNames.getCXXConstructorName(ClassType); 1086 CXXConstructorDecl *CopyConstructor 1087 = CXXConstructorDecl::Create(Context, ClassDecl, 1088 ClassDecl->getLocation(), Name, 1089 Context.getFunctionType(Context.VoidTy, 1090 &ArgType, 1, 1091 false, 0), 1092 /*isExplicit=*/false, 1093 /*isInline=*/true, 1094 /*isImplicitlyDeclared=*/true); 1095 CopyConstructor->setAccess(AS_public); 1096 CopyConstructor->setImplicit(); 1097 1098 // Add the parameter to the constructor. 1099 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, 1100 ClassDecl->getLocation(), 1101 /*IdentifierInfo=*/0, 1102 ArgType, VarDecl::None, 0); 1103 CopyConstructor->setParams(Context, &FromParam, 1); 1104 1105 ClassDecl->addedConstructor(Context, CopyConstructor); 1106 ClassDecl->addDecl(Context, CopyConstructor); 1107 } 1108 1109 if (!ClassDecl->hasUserDeclaredCopyAssignment()) { 1110 // Note: The following rules are largely analoguous to the copy 1111 // constructor rules. Note that virtual bases are not taken into account 1112 // for determining the argument type of the operator. Note also that 1113 // operators taking an object instead of a reference are allowed. 1114 // 1115 // C++ [class.copy]p10: 1116 // If the class definition does not explicitly declare a copy 1117 // assignment operator, one is declared implicitly. 1118 // The implicitly-defined copy assignment operator for a class X 1119 // will have the form 1120 // 1121 // X& X::operator=(const X&) 1122 // 1123 // if 1124 bool HasConstCopyAssignment = true; 1125 1126 // -- each direct base class B of X has a copy assignment operator 1127 // whose parameter is of type const B&, const volatile B& or B, 1128 // and 1129 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 1130 HasConstCopyAssignment && Base != ClassDecl->bases_end(); ++Base) { 1131 const CXXRecordDecl *BaseClassDecl 1132 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 1133 HasConstCopyAssignment = BaseClassDecl->hasConstCopyAssignment(Context); 1134 } 1135 1136 // -- for all the nonstatic data members of X that are of a class 1137 // type M (or array thereof), each such class type has a copy 1138 // assignment operator whose parameter is of type const M&, 1139 // const volatile M& or M. 1140 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(Context); 1141 HasConstCopyAssignment && Field != ClassDecl->field_end(Context); 1142 ++Field) { 1143 QualType FieldType = (*Field)->getType(); 1144 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 1145 FieldType = Array->getElementType(); 1146 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 1147 const CXXRecordDecl *FieldClassDecl 1148 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 1149 HasConstCopyAssignment 1150 = FieldClassDecl->hasConstCopyAssignment(Context); 1151 } 1152 } 1153 1154 // Otherwise, the implicitly declared copy assignment operator will 1155 // have the form 1156 // 1157 // X& X::operator=(X&) 1158 QualType ArgType = ClassType; 1159 QualType RetType = Context.getLValueReferenceType(ArgType); 1160 if (HasConstCopyAssignment) 1161 ArgType = ArgType.withConst(); 1162 ArgType = Context.getLValueReferenceType(ArgType); 1163 1164 // An implicitly-declared copy assignment operator is an inline public 1165 // member of its class. 1166 DeclarationName Name = 1167 Context.DeclarationNames.getCXXOperatorName(OO_Equal); 1168 CXXMethodDecl *CopyAssignment = 1169 CXXMethodDecl::Create(Context, ClassDecl, ClassDecl->getLocation(), Name, 1170 Context.getFunctionType(RetType, &ArgType, 1, 1171 false, 0), 1172 /*isStatic=*/false, /*isInline=*/true); 1173 CopyAssignment->setAccess(AS_public); 1174 CopyAssignment->setImplicit(); 1175 1176 // Add the parameter to the operator. 1177 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyAssignment, 1178 ClassDecl->getLocation(), 1179 /*IdentifierInfo=*/0, 1180 ArgType, VarDecl::None, 0); 1181 CopyAssignment->setParams(Context, &FromParam, 1); 1182 1183 // Don't call addedAssignmentOperator. There is no way to distinguish an 1184 // implicit from an explicit assignment operator. 1185 ClassDecl->addDecl(Context, CopyAssignment); 1186 } 1187 1188 if (!ClassDecl->hasUserDeclaredDestructor()) { 1189 // C++ [class.dtor]p2: 1190 // If a class has no user-declared destructor, a destructor is 1191 // declared implicitly. An implicitly-declared destructor is an 1192 // inline public member of its class. 1193 DeclarationName Name 1194 = Context.DeclarationNames.getCXXDestructorName(ClassType); 1195 CXXDestructorDecl *Destructor 1196 = CXXDestructorDecl::Create(Context, ClassDecl, 1197 ClassDecl->getLocation(), Name, 1198 Context.getFunctionType(Context.VoidTy, 1199 0, 0, false, 0), 1200 /*isInline=*/true, 1201 /*isImplicitlyDeclared=*/true); 1202 Destructor->setAccess(AS_public); 1203 Destructor->setImplicit(); 1204 ClassDecl->addDecl(Context, Destructor); 1205 } 1206} 1207 1208/// ActOnStartDelayedCXXMethodDeclaration - We have completed 1209/// parsing a top-level (non-nested) C++ class, and we are now 1210/// parsing those parts of the given Method declaration that could 1211/// not be parsed earlier (C++ [class.mem]p2), such as default 1212/// arguments. This action should enter the scope of the given 1213/// Method declaration as if we had just parsed the qualified method 1214/// name. However, it should not bring the parameters into scope; 1215/// that will be performed by ActOnDelayedCXXMethodParameter. 1216void Sema::ActOnStartDelayedCXXMethodDeclaration(Scope *S, DeclPtrTy MethodD) { 1217 CXXScopeSpec SS; 1218 FunctionDecl *Method = cast<FunctionDecl>(MethodD.getAs<Decl>()); 1219 QualType ClassTy 1220 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 1221 SS.setScopeRep( 1222 NestedNameSpecifier::Create(Context, 0, false, ClassTy.getTypePtr())); 1223 ActOnCXXEnterDeclaratorScope(S, SS); 1224} 1225 1226/// ActOnDelayedCXXMethodParameter - We've already started a delayed 1227/// C++ method declaration. We're (re-)introducing the given 1228/// function parameter into scope for use in parsing later parts of 1229/// the method declaration. For example, we could see an 1230/// ActOnParamDefaultArgument event for this parameter. 1231void Sema::ActOnDelayedCXXMethodParameter(Scope *S, DeclPtrTy ParamD) { 1232 ParmVarDecl *Param = cast<ParmVarDecl>(ParamD.getAs<Decl>()); 1233 1234 // If this parameter has an unparsed default argument, clear it out 1235 // to make way for the parsed default argument. 1236 if (Param->hasUnparsedDefaultArg()) 1237 Param->setDefaultArg(0); 1238 1239 S->AddDecl(DeclPtrTy::make(Param)); 1240 if (Param->getDeclName()) 1241 IdResolver.AddDecl(Param); 1242} 1243 1244/// ActOnFinishDelayedCXXMethodDeclaration - We have finished 1245/// processing the delayed method declaration for Method. The method 1246/// declaration is now considered finished. There may be a separate 1247/// ActOnStartOfFunctionDef action later (not necessarily 1248/// immediately!) for this method, if it was also defined inside the 1249/// class body. 1250void Sema::ActOnFinishDelayedCXXMethodDeclaration(Scope *S, DeclPtrTy MethodD) { 1251 FunctionDecl *Method = cast<FunctionDecl>(MethodD.getAs<Decl>()); 1252 CXXScopeSpec SS; 1253 QualType ClassTy 1254 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 1255 SS.setScopeRep( 1256 NestedNameSpecifier::Create(Context, 0, false, ClassTy.getTypePtr())); 1257 ActOnCXXExitDeclaratorScope(S, SS); 1258 1259 // Now that we have our default arguments, check the constructor 1260 // again. It could produce additional diagnostics or affect whether 1261 // the class has implicitly-declared destructors, among other 1262 // things. 1263 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Method)) 1264 CheckConstructor(Constructor); 1265 1266 // Check the default arguments, which we may have added. 1267 if (!Method->isInvalidDecl()) 1268 CheckCXXDefaultArguments(Method); 1269} 1270 1271/// CheckConstructorDeclarator - Called by ActOnDeclarator to check 1272/// the well-formedness of the constructor declarator @p D with type @p 1273/// R. If there are any errors in the declarator, this routine will 1274/// emit diagnostics and set the invalid bit to true. In any case, the type 1275/// will be updated to reflect a well-formed type for the constructor and 1276/// returned. 1277QualType Sema::CheckConstructorDeclarator(Declarator &D, QualType R, 1278 FunctionDecl::StorageClass &SC) { 1279 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1280 1281 // C++ [class.ctor]p3: 1282 // A constructor shall not be virtual (10.3) or static (9.4). A 1283 // constructor can be invoked for a const, volatile or const 1284 // volatile object. A constructor shall not be declared const, 1285 // volatile, or const volatile (9.3.2). 1286 if (isVirtual) { 1287 if (!D.isInvalidType()) 1288 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be) 1289 << "virtual" << SourceRange(D.getDeclSpec().getVirtualSpecLoc()) 1290 << SourceRange(D.getIdentifierLoc()); 1291 D.setInvalidType(); 1292 } 1293 if (SC == FunctionDecl::Static) { 1294 if (!D.isInvalidType()) 1295 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be) 1296 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1297 << SourceRange(D.getIdentifierLoc()); 1298 D.setInvalidType(); 1299 SC = FunctionDecl::None; 1300 } 1301 1302 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1303 if (FTI.TypeQuals != 0) { 1304 if (FTI.TypeQuals & QualType::Const) 1305 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1306 << "const" << SourceRange(D.getIdentifierLoc()); 1307 if (FTI.TypeQuals & QualType::Volatile) 1308 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1309 << "volatile" << SourceRange(D.getIdentifierLoc()); 1310 if (FTI.TypeQuals & QualType::Restrict) 1311 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1312 << "restrict" << SourceRange(D.getIdentifierLoc()); 1313 } 1314 1315 // Rebuild the function type "R" without any type qualifiers (in 1316 // case any of the errors above fired) and with "void" as the 1317 // return type, since constructors don't have return types. We 1318 // *always* have to do this, because GetTypeForDeclarator will 1319 // put in a result type of "int" when none was specified. 1320 const FunctionProtoType *Proto = R->getAsFunctionProtoType(); 1321 return Context.getFunctionType(Context.VoidTy, Proto->arg_type_begin(), 1322 Proto->getNumArgs(), 1323 Proto->isVariadic(), 0); 1324} 1325 1326/// CheckConstructor - Checks a fully-formed constructor for 1327/// well-formedness, issuing any diagnostics required. Returns true if 1328/// the constructor declarator is invalid. 1329void Sema::CheckConstructor(CXXConstructorDecl *Constructor) { 1330 CXXRecordDecl *ClassDecl 1331 = dyn_cast<CXXRecordDecl>(Constructor->getDeclContext()); 1332 if (!ClassDecl) 1333 return Constructor->setInvalidDecl(); 1334 1335 // C++ [class.copy]p3: 1336 // A declaration of a constructor for a class X is ill-formed if 1337 // its first parameter is of type (optionally cv-qualified) X and 1338 // either there are no other parameters or else all other 1339 // parameters have default arguments. 1340 if (!Constructor->isInvalidDecl() && 1341 ((Constructor->getNumParams() == 1) || 1342 (Constructor->getNumParams() > 1 && 1343 Constructor->getParamDecl(1)->getDefaultArg() != 0))) { 1344 QualType ParamType = Constructor->getParamDecl(0)->getType(); 1345 QualType ClassTy = Context.getTagDeclType(ClassDecl); 1346 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { 1347 SourceLocation ParamLoc = Constructor->getParamDecl(0)->getLocation(); 1348 Diag(ParamLoc, diag::err_constructor_byvalue_arg) 1349 << CodeModificationHint::CreateInsertion(ParamLoc, " const &"); 1350 Constructor->setInvalidDecl(); 1351 } 1352 } 1353 1354 // Notify the class that we've added a constructor. 1355 ClassDecl->addedConstructor(Context, Constructor); 1356} 1357 1358static inline bool 1359FTIHasSingleVoidArgument(DeclaratorChunk::FunctionTypeInfo &FTI) { 1360 return (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1361 FTI.ArgInfo[0].Param && 1362 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()); 1363} 1364 1365/// CheckDestructorDeclarator - Called by ActOnDeclarator to check 1366/// the well-formednes of the destructor declarator @p D with type @p 1367/// R. If there are any errors in the declarator, this routine will 1368/// emit diagnostics and set the declarator to invalid. Even if this happens, 1369/// will be updated to reflect a well-formed type for the destructor and 1370/// returned. 1371QualType Sema::CheckDestructorDeclarator(Declarator &D, 1372 FunctionDecl::StorageClass& SC) { 1373 // C++ [class.dtor]p1: 1374 // [...] A typedef-name that names a class is a class-name 1375 // (7.1.3); however, a typedef-name that names a class shall not 1376 // be used as the identifier in the declarator for a destructor 1377 // declaration. 1378 QualType DeclaratorType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1379 if (isa<TypedefType>(DeclaratorType)) { 1380 Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name) 1381 << DeclaratorType; 1382 D.setInvalidType(); 1383 } 1384 1385 // C++ [class.dtor]p2: 1386 // A destructor is used to destroy objects of its class type. A 1387 // destructor takes no parameters, and no return type can be 1388 // specified for it (not even void). The address of a destructor 1389 // shall not be taken. A destructor shall not be static. A 1390 // destructor can be invoked for a const, volatile or const 1391 // volatile object. A destructor shall not be declared const, 1392 // volatile or const volatile (9.3.2). 1393 if (SC == FunctionDecl::Static) { 1394 if (!D.isInvalidType()) 1395 Diag(D.getIdentifierLoc(), diag::err_destructor_cannot_be) 1396 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1397 << SourceRange(D.getIdentifierLoc()); 1398 SC = FunctionDecl::None; 1399 D.setInvalidType(); 1400 } 1401 if (D.getDeclSpec().hasTypeSpecifier() && !D.isInvalidType()) { 1402 // Destructors don't have return types, but the parser will 1403 // happily parse something like: 1404 // 1405 // class X { 1406 // float ~X(); 1407 // }; 1408 // 1409 // The return type will be eliminated later. 1410 Diag(D.getIdentifierLoc(), diag::err_destructor_return_type) 1411 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 1412 << SourceRange(D.getIdentifierLoc()); 1413 } 1414 1415 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1416 if (FTI.TypeQuals != 0 && !D.isInvalidType()) { 1417 if (FTI.TypeQuals & QualType::Const) 1418 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1419 << "const" << SourceRange(D.getIdentifierLoc()); 1420 if (FTI.TypeQuals & QualType::Volatile) 1421 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1422 << "volatile" << SourceRange(D.getIdentifierLoc()); 1423 if (FTI.TypeQuals & QualType::Restrict) 1424 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1425 << "restrict" << SourceRange(D.getIdentifierLoc()); 1426 D.setInvalidType(); 1427 } 1428 1429 // Make sure we don't have any parameters. 1430 if (FTI.NumArgs > 0 && !FTIHasSingleVoidArgument(FTI)) { 1431 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params); 1432 1433 // Delete the parameters. 1434 FTI.freeArgs(); 1435 D.setInvalidType(); 1436 } 1437 1438 // Make sure the destructor isn't variadic. 1439 if (FTI.isVariadic) { 1440 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic); 1441 D.setInvalidType(); 1442 } 1443 1444 // Rebuild the function type "R" without any type qualifiers or 1445 // parameters (in case any of the errors above fired) and with 1446 // "void" as the return type, since destructors don't have return 1447 // types. We *always* have to do this, because GetTypeForDeclarator 1448 // will put in a result type of "int" when none was specified. 1449 return Context.getFunctionType(Context.VoidTy, 0, 0, false, 0); 1450} 1451 1452/// CheckConversionDeclarator - Called by ActOnDeclarator to check the 1453/// well-formednes of the conversion function declarator @p D with 1454/// type @p R. If there are any errors in the declarator, this routine 1455/// will emit diagnostics and return true. Otherwise, it will return 1456/// false. Either way, the type @p R will be updated to reflect a 1457/// well-formed type for the conversion operator. 1458void Sema::CheckConversionDeclarator(Declarator &D, QualType &R, 1459 FunctionDecl::StorageClass& SC) { 1460 // C++ [class.conv.fct]p1: 1461 // Neither parameter types nor return type can be specified. The 1462 // type of a conversion function (8.3.5) is “function taking no 1463 // parameter returning conversion-type-id.” 1464 if (SC == FunctionDecl::Static) { 1465 if (!D.isInvalidType()) 1466 Diag(D.getIdentifierLoc(), diag::err_conv_function_not_member) 1467 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1468 << SourceRange(D.getIdentifierLoc()); 1469 D.setInvalidType(); 1470 SC = FunctionDecl::None; 1471 } 1472 if (D.getDeclSpec().hasTypeSpecifier() && !D.isInvalidType()) { 1473 // Conversion functions don't have return types, but the parser will 1474 // happily parse something like: 1475 // 1476 // class X { 1477 // float operator bool(); 1478 // }; 1479 // 1480 // The return type will be changed later anyway. 1481 Diag(D.getIdentifierLoc(), diag::err_conv_function_return_type) 1482 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 1483 << SourceRange(D.getIdentifierLoc()); 1484 } 1485 1486 // Make sure we don't have any parameters. 1487 if (R->getAsFunctionProtoType()->getNumArgs() > 0) { 1488 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params); 1489 1490 // Delete the parameters. 1491 D.getTypeObject(0).Fun.freeArgs(); 1492 D.setInvalidType(); 1493 } 1494 1495 // Make sure the conversion function isn't variadic. 1496 if (R->getAsFunctionProtoType()->isVariadic() && !D.isInvalidType()) { 1497 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic); 1498 D.setInvalidType(); 1499 } 1500 1501 // C++ [class.conv.fct]p4: 1502 // The conversion-type-id shall not represent a function type nor 1503 // an array type. 1504 QualType ConvType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1505 if (ConvType->isArrayType()) { 1506 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array); 1507 ConvType = Context.getPointerType(ConvType); 1508 D.setInvalidType(); 1509 } else if (ConvType->isFunctionType()) { 1510 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function); 1511 ConvType = Context.getPointerType(ConvType); 1512 D.setInvalidType(); 1513 } 1514 1515 // Rebuild the function type "R" without any parameters (in case any 1516 // of the errors above fired) and with the conversion type as the 1517 // return type. 1518 R = Context.getFunctionType(ConvType, 0, 0, false, 1519 R->getAsFunctionProtoType()->getTypeQuals()); 1520 1521 // C++0x explicit conversion operators. 1522 if (D.getDeclSpec().isExplicitSpecified() && !getLangOptions().CPlusPlus0x) 1523 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1524 diag::warn_explicit_conversion_functions) 1525 << SourceRange(D.getDeclSpec().getExplicitSpecLoc()); 1526} 1527 1528/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete 1529/// the declaration of the given C++ conversion function. This routine 1530/// is responsible for recording the conversion function in the C++ 1531/// class, if possible. 1532Sema::DeclPtrTy Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) { 1533 assert(Conversion && "Expected to receive a conversion function declaration"); 1534 1535 // Set the lexical context of this conversion function 1536 Conversion->setLexicalDeclContext(CurContext); 1537 1538 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Conversion->getDeclContext()); 1539 1540 // Make sure we aren't redeclaring the conversion function. 1541 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType()); 1542 1543 // C++ [class.conv.fct]p1: 1544 // [...] A conversion function is never used to convert a 1545 // (possibly cv-qualified) object to the (possibly cv-qualified) 1546 // same object type (or a reference to it), to a (possibly 1547 // cv-qualified) base class of that type (or a reference to it), 1548 // or to (possibly cv-qualified) void. 1549 // FIXME: Suppress this warning if the conversion function ends up being a 1550 // virtual function that overrides a virtual function in a base class. 1551 QualType ClassType 1552 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl)); 1553 if (const ReferenceType *ConvTypeRef = ConvType->getAsReferenceType()) 1554 ConvType = ConvTypeRef->getPointeeType(); 1555 if (ConvType->isRecordType()) { 1556 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType(); 1557 if (ConvType == ClassType) 1558 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used) 1559 << ClassType; 1560 else if (IsDerivedFrom(ClassType, ConvType)) 1561 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used) 1562 << ClassType << ConvType; 1563 } else if (ConvType->isVoidType()) { 1564 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used) 1565 << ClassType << ConvType; 1566 } 1567 1568 if (Conversion->getPreviousDeclaration()) { 1569 OverloadedFunctionDecl *Conversions = ClassDecl->getConversionFunctions(); 1570 for (OverloadedFunctionDecl::function_iterator 1571 Conv = Conversions->function_begin(), 1572 ConvEnd = Conversions->function_end(); 1573 Conv != ConvEnd; ++Conv) { 1574 if (*Conv == Conversion->getPreviousDeclaration()) { 1575 *Conv = Conversion; 1576 return DeclPtrTy::make(Conversion); 1577 } 1578 } 1579 assert(Conversion->isInvalidDecl() && "Conversion should not get here."); 1580 } else 1581 ClassDecl->addConversionFunction(Context, Conversion); 1582 1583 return DeclPtrTy::make(Conversion); 1584} 1585 1586//===----------------------------------------------------------------------===// 1587// Namespace Handling 1588//===----------------------------------------------------------------------===// 1589 1590/// ActOnStartNamespaceDef - This is called at the start of a namespace 1591/// definition. 1592Sema::DeclPtrTy Sema::ActOnStartNamespaceDef(Scope *NamespcScope, 1593 SourceLocation IdentLoc, 1594 IdentifierInfo *II, 1595 SourceLocation LBrace) { 1596 NamespaceDecl *Namespc = 1597 NamespaceDecl::Create(Context, CurContext, IdentLoc, II); 1598 Namespc->setLBracLoc(LBrace); 1599 1600 Scope *DeclRegionScope = NamespcScope->getParent(); 1601 1602 if (II) { 1603 // C++ [namespace.def]p2: 1604 // The identifier in an original-namespace-definition shall not have been 1605 // previously defined in the declarative region in which the 1606 // original-namespace-definition appears. The identifier in an 1607 // original-namespace-definition is the name of the namespace. Subsequently 1608 // in that declarative region, it is treated as an original-namespace-name. 1609 1610 NamedDecl *PrevDecl = LookupName(DeclRegionScope, II, LookupOrdinaryName, 1611 true); 1612 1613 if (NamespaceDecl *OrigNS = dyn_cast_or_null<NamespaceDecl>(PrevDecl)) { 1614 // This is an extended namespace definition. 1615 // Attach this namespace decl to the chain of extended namespace 1616 // definitions. 1617 OrigNS->setNextNamespace(Namespc); 1618 Namespc->setOriginalNamespace(OrigNS->getOriginalNamespace()); 1619 1620 // Remove the previous declaration from the scope. 1621 if (DeclRegionScope->isDeclScope(DeclPtrTy::make(OrigNS))) { 1622 IdResolver.RemoveDecl(OrigNS); 1623 DeclRegionScope->RemoveDecl(DeclPtrTy::make(OrigNS)); 1624 } 1625 } else if (PrevDecl) { 1626 // This is an invalid name redefinition. 1627 Diag(Namespc->getLocation(), diag::err_redefinition_different_kind) 1628 << Namespc->getDeclName(); 1629 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 1630 Namespc->setInvalidDecl(); 1631 // Continue on to push Namespc as current DeclContext and return it. 1632 } 1633 1634 PushOnScopeChains(Namespc, DeclRegionScope); 1635 } else { 1636 // FIXME: Handle anonymous namespaces 1637 } 1638 1639 // Although we could have an invalid decl (i.e. the namespace name is a 1640 // redefinition), push it as current DeclContext and try to continue parsing. 1641 // FIXME: We should be able to push Namespc here, so that the each DeclContext 1642 // for the namespace has the declarations that showed up in that particular 1643 // namespace definition. 1644 PushDeclContext(NamespcScope, Namespc); 1645 return DeclPtrTy::make(Namespc); 1646} 1647 1648/// ActOnFinishNamespaceDef - This callback is called after a namespace is 1649/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. 1650void Sema::ActOnFinishNamespaceDef(DeclPtrTy D, SourceLocation RBrace) { 1651 Decl *Dcl = D.getAs<Decl>(); 1652 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); 1653 assert(Namespc && "Invalid parameter, expected NamespaceDecl"); 1654 Namespc->setRBracLoc(RBrace); 1655 PopDeclContext(); 1656} 1657 1658Sema::DeclPtrTy Sema::ActOnUsingDirective(Scope *S, 1659 SourceLocation UsingLoc, 1660 SourceLocation NamespcLoc, 1661 const CXXScopeSpec &SS, 1662 SourceLocation IdentLoc, 1663 IdentifierInfo *NamespcName, 1664 AttributeList *AttrList) { 1665 assert(!SS.isInvalid() && "Invalid CXXScopeSpec."); 1666 assert(NamespcName && "Invalid NamespcName."); 1667 assert(IdentLoc.isValid() && "Invalid NamespceName location."); 1668 assert(S->getFlags() & Scope::DeclScope && "Invalid Scope."); 1669 1670 UsingDirectiveDecl *UDir = 0; 1671 1672 // Lookup namespace name. 1673 LookupResult R = LookupParsedName(S, &SS, NamespcName, 1674 LookupNamespaceName, false); 1675 if (R.isAmbiguous()) { 1676 DiagnoseAmbiguousLookup(R, NamespcName, IdentLoc); 1677 return DeclPtrTy(); 1678 } 1679 if (NamedDecl *NS = R) { 1680 assert(isa<NamespaceDecl>(NS) && "expected namespace decl"); 1681 // C++ [namespace.udir]p1: 1682 // A using-directive specifies that the names in the nominated 1683 // namespace can be used in the scope in which the 1684 // using-directive appears after the using-directive. During 1685 // unqualified name lookup (3.4.1), the names appear as if they 1686 // were declared in the nearest enclosing namespace which 1687 // contains both the using-directive and the nominated 1688 // namespace. [Note: in this context, “contains” means “contains 1689 // directly or indirectly”. ] 1690 1691 // Find enclosing context containing both using-directive and 1692 // nominated namespace. 1693 DeclContext *CommonAncestor = cast<DeclContext>(NS); 1694 while (CommonAncestor && !CommonAncestor->Encloses(CurContext)) 1695 CommonAncestor = CommonAncestor->getParent(); 1696 1697 UDir = UsingDirectiveDecl::Create(Context, CurContext, UsingLoc, 1698 NamespcLoc, IdentLoc, 1699 cast<NamespaceDecl>(NS), 1700 CommonAncestor); 1701 PushUsingDirective(S, UDir); 1702 } else { 1703 Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange(); 1704 } 1705 1706 // FIXME: We ignore attributes for now. 1707 delete AttrList; 1708 return DeclPtrTy::make(UDir); 1709} 1710 1711void Sema::PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir) { 1712 // If scope has associated entity, then using directive is at namespace 1713 // or translation unit scope. We add UsingDirectiveDecls, into 1714 // it's lookup structure. 1715 if (DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity())) 1716 Ctx->addDecl(Context, UDir); 1717 else 1718 // Otherwise it is block-sope. using-directives will affect lookup 1719 // only to the end of scope. 1720 S->PushUsingDirective(DeclPtrTy::make(UDir)); 1721} 1722 1723/// getNamespaceDecl - Returns the namespace a decl represents. If the decl 1724/// is a namespace alias, returns the namespace it points to. 1725static inline NamespaceDecl *getNamespaceDecl(NamedDecl *D) { 1726 if (NamespaceAliasDecl *AD = dyn_cast_or_null<NamespaceAliasDecl>(D)) 1727 return AD->getNamespace(); 1728 return dyn_cast_or_null<NamespaceDecl>(D); 1729} 1730 1731Sema::DeclPtrTy Sema::ActOnNamespaceAliasDef(Scope *S, 1732 SourceLocation NamespaceLoc, 1733 SourceLocation AliasLoc, 1734 IdentifierInfo *Alias, 1735 const CXXScopeSpec &SS, 1736 SourceLocation IdentLoc, 1737 IdentifierInfo *Ident) { 1738 1739 // Lookup the namespace name. 1740 LookupResult R = LookupParsedName(S, &SS, Ident, LookupNamespaceName, false); 1741 1742 // Check if we have a previous declaration with the same name. 1743 if (NamedDecl *PrevDecl = LookupName(S, Alias, LookupOrdinaryName, true)) { 1744 if (NamespaceAliasDecl *AD = dyn_cast<NamespaceAliasDecl>(PrevDecl)) { 1745 // We already have an alias with the same name that points to the same 1746 // namespace, so don't create a new one. 1747 if (!R.isAmbiguous() && AD->getNamespace() == getNamespaceDecl(R)) 1748 return DeclPtrTy(); 1749 } 1750 1751 unsigned DiagID = isa<NamespaceDecl>(PrevDecl) ? diag::err_redefinition : 1752 diag::err_redefinition_different_kind; 1753 Diag(AliasLoc, DiagID) << Alias; 1754 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 1755 return DeclPtrTy(); 1756 } 1757 1758 if (R.isAmbiguous()) { 1759 DiagnoseAmbiguousLookup(R, Ident, IdentLoc); 1760 return DeclPtrTy(); 1761 } 1762 1763 if (!R) { 1764 Diag(NamespaceLoc, diag::err_expected_namespace_name) << SS.getRange(); 1765 return DeclPtrTy(); 1766 } 1767 1768 NamespaceAliasDecl *AliasDecl = 1769 NamespaceAliasDecl::Create(Context, CurContext, NamespaceLoc, AliasLoc, Alias, 1770 IdentLoc, R); 1771 1772 CurContext->addDecl(Context, AliasDecl); 1773 return DeclPtrTy::make(AliasDecl); 1774} 1775 1776void Sema::InitializeVarWithConstructor(VarDecl *VD, 1777 CXXConstructorDecl *Constructor, 1778 QualType DeclInitType, 1779 Expr **Exprs, unsigned NumExprs) { 1780 Expr *Temp = CXXConstructExpr::Create(Context, VD, DeclInitType, Constructor, 1781 false, Exprs, NumExprs); 1782 VD->setInit(Context, Temp); 1783} 1784 1785/// AddCXXDirectInitializerToDecl - This action is called immediately after 1786/// ActOnDeclarator, when a C++ direct initializer is present. 1787/// e.g: "int x(1);" 1788void Sema::AddCXXDirectInitializerToDecl(DeclPtrTy Dcl, 1789 SourceLocation LParenLoc, 1790 MultiExprArg Exprs, 1791 SourceLocation *CommaLocs, 1792 SourceLocation RParenLoc) { 1793 unsigned NumExprs = Exprs.size(); 1794 assert(NumExprs != 0 && Exprs.get() && "missing expressions"); 1795 Decl *RealDecl = Dcl.getAs<Decl>(); 1796 1797 // If there is no declaration, there was an error parsing it. Just ignore 1798 // the initializer. 1799 if (RealDecl == 0) 1800 return; 1801 1802 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1803 if (!VDecl) { 1804 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 1805 RealDecl->setInvalidDecl(); 1806 return; 1807 } 1808 1809 // FIXME: Need to handle dependent types and expressions here. 1810 1811 // We will treat direct-initialization as a copy-initialization: 1812 // int x(1); -as-> int x = 1; 1813 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); 1814 // 1815 // Clients that want to distinguish between the two forms, can check for 1816 // direct initializer using VarDecl::hasCXXDirectInitializer(). 1817 // A major benefit is that clients that don't particularly care about which 1818 // exactly form was it (like the CodeGen) can handle both cases without 1819 // special case code. 1820 1821 // C++ 8.5p11: 1822 // The form of initialization (using parentheses or '=') is generally 1823 // insignificant, but does matter when the entity being initialized has a 1824 // class type. 1825 QualType DeclInitType = VDecl->getType(); 1826 if (const ArrayType *Array = Context.getAsArrayType(DeclInitType)) 1827 DeclInitType = Array->getElementType(); 1828 1829 // FIXME: This isn't the right place to complete the type. 1830 if (RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 1831 diag::err_typecheck_decl_incomplete_type)) { 1832 VDecl->setInvalidDecl(); 1833 return; 1834 } 1835 1836 if (VDecl->getType()->isRecordType()) { 1837 CXXConstructorDecl *Constructor 1838 = PerformInitializationByConstructor(DeclInitType, 1839 (Expr **)Exprs.get(), NumExprs, 1840 VDecl->getLocation(), 1841 SourceRange(VDecl->getLocation(), 1842 RParenLoc), 1843 VDecl->getDeclName(), 1844 IK_Direct); 1845 if (!Constructor) 1846 RealDecl->setInvalidDecl(); 1847 else { 1848 VDecl->setCXXDirectInitializer(true); 1849 InitializeVarWithConstructor(VDecl, Constructor, DeclInitType, 1850 (Expr**)Exprs.release(), NumExprs); 1851 } 1852 return; 1853 } 1854 1855 if (NumExprs > 1) { 1856 Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg) 1857 << SourceRange(VDecl->getLocation(), RParenLoc); 1858 RealDecl->setInvalidDecl(); 1859 return; 1860 } 1861 1862 // Let clients know that initialization was done with a direct initializer. 1863 VDecl->setCXXDirectInitializer(true); 1864 1865 assert(NumExprs == 1 && "Expected 1 expression"); 1866 // Set the init expression, handles conversions. 1867 AddInitializerToDecl(Dcl, ExprArg(*this, Exprs.release()[0]), 1868 /*DirectInit=*/true); 1869} 1870 1871/// PerformInitializationByConstructor - Perform initialization by 1872/// constructor (C++ [dcl.init]p14), which may occur as part of 1873/// direct-initialization or copy-initialization. We are initializing 1874/// an object of type @p ClassType with the given arguments @p 1875/// Args. @p Loc is the location in the source code where the 1876/// initializer occurs (e.g., a declaration, member initializer, 1877/// functional cast, etc.) while @p Range covers the whole 1878/// initialization. @p InitEntity is the entity being initialized, 1879/// which may by the name of a declaration or a type. @p Kind is the 1880/// kind of initialization we're performing, which affects whether 1881/// explicit constructors will be considered. When successful, returns 1882/// the constructor that will be used to perform the initialization; 1883/// when the initialization fails, emits a diagnostic and returns 1884/// null. 1885CXXConstructorDecl * 1886Sema::PerformInitializationByConstructor(QualType ClassType, 1887 Expr **Args, unsigned NumArgs, 1888 SourceLocation Loc, SourceRange Range, 1889 DeclarationName InitEntity, 1890 InitializationKind Kind) { 1891 const RecordType *ClassRec = ClassType->getAsRecordType(); 1892 assert(ClassRec && "Can only initialize a class type here"); 1893 1894 // C++ [dcl.init]p14: 1895 // 1896 // If the initialization is direct-initialization, or if it is 1897 // copy-initialization where the cv-unqualified version of the 1898 // source type is the same class as, or a derived class of, the 1899 // class of the destination, constructors are considered. The 1900 // applicable constructors are enumerated (13.3.1.3), and the 1901 // best one is chosen through overload resolution (13.3). The 1902 // constructor so selected is called to initialize the object, 1903 // with the initializer expression(s) as its argument(s). If no 1904 // constructor applies, or the overload resolution is ambiguous, 1905 // the initialization is ill-formed. 1906 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1907 OverloadCandidateSet CandidateSet; 1908 1909 // Add constructors to the overload set. 1910 DeclarationName ConstructorName 1911 = Context.DeclarationNames.getCXXConstructorName( 1912 Context.getCanonicalType(ClassType.getUnqualifiedType())); 1913 DeclContext::lookup_const_iterator Con, ConEnd; 1914 for (llvm::tie(Con, ConEnd) = ClassDecl->lookup(Context, ConstructorName); 1915 Con != ConEnd; ++Con) { 1916 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 1917 if ((Kind == IK_Direct) || 1918 (Kind == IK_Copy && Constructor->isConvertingConstructor()) || 1919 (Kind == IK_Default && Constructor->isDefaultConstructor())) 1920 AddOverloadCandidate(Constructor, Args, NumArgs, CandidateSet); 1921 } 1922 1923 // FIXME: When we decide not to synthesize the implicitly-declared 1924 // constructors, we'll need to make them appear here. 1925 1926 OverloadCandidateSet::iterator Best; 1927 switch (BestViableFunction(CandidateSet, Best)) { 1928 case OR_Success: 1929 // We found a constructor. Return it. 1930 return cast<CXXConstructorDecl>(Best->Function); 1931 1932 case OR_No_Viable_Function: 1933 if (InitEntity) 1934 Diag(Loc, diag::err_ovl_no_viable_function_in_init) 1935 << InitEntity << Range; 1936 else 1937 Diag(Loc, diag::err_ovl_no_viable_function_in_init) 1938 << ClassType << Range; 1939 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1940 return 0; 1941 1942 case OR_Ambiguous: 1943 if (InitEntity) 1944 Diag(Loc, diag::err_ovl_ambiguous_init) << InitEntity << Range; 1945 else 1946 Diag(Loc, diag::err_ovl_ambiguous_init) << ClassType << Range; 1947 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1948 return 0; 1949 1950 case OR_Deleted: 1951 if (InitEntity) 1952 Diag(Loc, diag::err_ovl_deleted_init) 1953 << Best->Function->isDeleted() 1954 << InitEntity << Range; 1955 else 1956 Diag(Loc, diag::err_ovl_deleted_init) 1957 << Best->Function->isDeleted() 1958 << InitEntity << Range; 1959 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1960 return 0; 1961 } 1962 1963 return 0; 1964} 1965 1966/// CompareReferenceRelationship - Compare the two types T1 and T2 to 1967/// determine whether they are reference-related, 1968/// reference-compatible, reference-compatible with added 1969/// qualification, or incompatible, for use in C++ initialization by 1970/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 1971/// type, and the first type (T1) is the pointee type of the reference 1972/// type being initialized. 1973Sema::ReferenceCompareResult 1974Sema::CompareReferenceRelationship(QualType T1, QualType T2, 1975 bool& DerivedToBase) { 1976 assert(!T1->isReferenceType() && 1977 "T1 must be the pointee type of the reference type"); 1978 assert(!T2->isReferenceType() && "T2 cannot be a reference type"); 1979 1980 T1 = Context.getCanonicalType(T1); 1981 T2 = Context.getCanonicalType(T2); 1982 QualType UnqualT1 = T1.getUnqualifiedType(); 1983 QualType UnqualT2 = T2.getUnqualifiedType(); 1984 1985 // C++ [dcl.init.ref]p4: 1986 // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is 1987 // reference-related to “cv2 T2” if T1 is the same type as T2, or 1988 // T1 is a base class of T2. 1989 if (UnqualT1 == UnqualT2) 1990 DerivedToBase = false; 1991 else if (IsDerivedFrom(UnqualT2, UnqualT1)) 1992 DerivedToBase = true; 1993 else 1994 return Ref_Incompatible; 1995 1996 // At this point, we know that T1 and T2 are reference-related (at 1997 // least). 1998 1999 // C++ [dcl.init.ref]p4: 2000 // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is 2001 // reference-related to T2 and cv1 is the same cv-qualification 2002 // as, or greater cv-qualification than, cv2. For purposes of 2003 // overload resolution, cases for which cv1 is greater 2004 // cv-qualification than cv2 are identified as 2005 // reference-compatible with added qualification (see 13.3.3.2). 2006 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 2007 return Ref_Compatible; 2008 else if (T1.isMoreQualifiedThan(T2)) 2009 return Ref_Compatible_With_Added_Qualification; 2010 else 2011 return Ref_Related; 2012} 2013 2014/// CheckReferenceInit - Check the initialization of a reference 2015/// variable with the given initializer (C++ [dcl.init.ref]). Init is 2016/// the initializer (either a simple initializer or an initializer 2017/// list), and DeclType is the type of the declaration. When ICS is 2018/// non-null, this routine will compute the implicit conversion 2019/// sequence according to C++ [over.ics.ref] and will not produce any 2020/// diagnostics; when ICS is null, it will emit diagnostics when any 2021/// errors are found. Either way, a return value of true indicates 2022/// that there was a failure, a return value of false indicates that 2023/// the reference initialization succeeded. 2024/// 2025/// When @p SuppressUserConversions, user-defined conversions are 2026/// suppressed. 2027/// When @p AllowExplicit, we also permit explicit user-defined 2028/// conversion functions. 2029/// When @p ForceRValue, we unconditionally treat the initializer as an rvalue. 2030bool 2031Sema::CheckReferenceInit(Expr *&Init, QualType DeclType, 2032 ImplicitConversionSequence *ICS, 2033 bool SuppressUserConversions, 2034 bool AllowExplicit, bool ForceRValue) { 2035 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 2036 2037 QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); 2038 QualType T2 = Init->getType(); 2039 2040 // If the initializer is the address of an overloaded function, try 2041 // to resolve the overloaded function. If all goes well, T2 is the 2042 // type of the resulting function. 2043 if (Context.getCanonicalType(T2) == Context.OverloadTy) { 2044 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Init, DeclType, 2045 ICS != 0); 2046 if (Fn) { 2047 // Since we're performing this reference-initialization for 2048 // real, update the initializer with the resulting function. 2049 if (!ICS) { 2050 if (DiagnoseUseOfDecl(Fn, Init->getSourceRange().getBegin())) 2051 return true; 2052 2053 FixOverloadedFunctionReference(Init, Fn); 2054 } 2055 2056 T2 = Fn->getType(); 2057 } 2058 } 2059 2060 // Compute some basic properties of the types and the initializer. 2061 bool isRValRef = DeclType->isRValueReferenceType(); 2062 bool DerivedToBase = false; 2063 Expr::isLvalueResult InitLvalue = ForceRValue ? Expr::LV_InvalidExpression : 2064 Init->isLvalue(Context); 2065 ReferenceCompareResult RefRelationship 2066 = CompareReferenceRelationship(T1, T2, DerivedToBase); 2067 2068 // Most paths end in a failed conversion. 2069 if (ICS) 2070 ICS->ConversionKind = ImplicitConversionSequence::BadConversion; 2071 2072 // C++ [dcl.init.ref]p5: 2073 // A reference to type “cv1 T1” is initialized by an expression 2074 // of type “cv2 T2” as follows: 2075 2076 // -- If the initializer expression 2077 2078 // Rvalue references cannot bind to lvalues (N2812). 2079 // There is absolutely no situation where they can. In particular, note that 2080 // this is ill-formed, even if B has a user-defined conversion to A&&: 2081 // B b; 2082 // A&& r = b; 2083 if (isRValRef && InitLvalue == Expr::LV_Valid) { 2084 if (!ICS) 2085 Diag(Init->getSourceRange().getBegin(), diag::err_lvalue_to_rvalue_ref) 2086 << Init->getSourceRange(); 2087 return true; 2088 } 2089 2090 bool BindsDirectly = false; 2091 // -- is an lvalue (but is not a bit-field), and “cv1 T1” is 2092 // reference-compatible with “cv2 T2,” or 2093 // 2094 // Note that the bit-field check is skipped if we are just computing 2095 // the implicit conversion sequence (C++ [over.best.ics]p2). 2096 if (InitLvalue == Expr::LV_Valid && (ICS || !Init->getBitField()) && 2097 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 2098 BindsDirectly = true; 2099 2100 if (ICS) { 2101 // C++ [over.ics.ref]p1: 2102 // When a parameter of reference type binds directly (8.5.3) 2103 // to an argument expression, the implicit conversion sequence 2104 // is the identity conversion, unless the argument expression 2105 // has a type that is a derived class of the parameter type, 2106 // in which case the implicit conversion sequence is a 2107 // derived-to-base Conversion (13.3.3.1). 2108 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 2109 ICS->Standard.First = ICK_Identity; 2110 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 2111 ICS->Standard.Third = ICK_Identity; 2112 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 2113 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 2114 ICS->Standard.ReferenceBinding = true; 2115 ICS->Standard.DirectBinding = true; 2116 ICS->Standard.RRefBinding = false; 2117 ICS->Standard.CopyConstructor = 0; 2118 2119 // Nothing more to do: the inaccessibility/ambiguity check for 2120 // derived-to-base conversions is suppressed when we're 2121 // computing the implicit conversion sequence (C++ 2122 // [over.best.ics]p2). 2123 return false; 2124 } else { 2125 // Perform the conversion. 2126 // FIXME: Binding to a subobject of the lvalue is going to require more 2127 // AST annotation than this. 2128 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 2129 } 2130 } 2131 2132 // -- has a class type (i.e., T2 is a class type) and can be 2133 // implicitly converted to an lvalue of type “cv3 T3,” 2134 // where “cv1 T1” is reference-compatible with “cv3 T3” 2135 // 92) (this conversion is selected by enumerating the 2136 // applicable conversion functions (13.3.1.6) and choosing 2137 // the best one through overload resolution (13.3)), 2138 if (!isRValRef && !SuppressUserConversions && T2->isRecordType()) { 2139 // FIXME: Look for conversions in base classes! 2140 CXXRecordDecl *T2RecordDecl 2141 = dyn_cast<CXXRecordDecl>(T2->getAsRecordType()->getDecl()); 2142 2143 OverloadCandidateSet CandidateSet; 2144 OverloadedFunctionDecl *Conversions 2145 = T2RecordDecl->getConversionFunctions(); 2146 for (OverloadedFunctionDecl::function_iterator Func 2147 = Conversions->function_begin(); 2148 Func != Conversions->function_end(); ++Func) { 2149 CXXConversionDecl *Conv = cast<CXXConversionDecl>(*Func); 2150 2151 // If the conversion function doesn't return a reference type, 2152 // it can't be considered for this conversion. 2153 if (Conv->getConversionType()->isLValueReferenceType() && 2154 (AllowExplicit || !Conv->isExplicit())) 2155 AddConversionCandidate(Conv, Init, DeclType, CandidateSet); 2156 } 2157 2158 OverloadCandidateSet::iterator Best; 2159 switch (BestViableFunction(CandidateSet, Best)) { 2160 case OR_Success: 2161 // This is a direct binding. 2162 BindsDirectly = true; 2163 2164 if (ICS) { 2165 // C++ [over.ics.ref]p1: 2166 // 2167 // [...] If the parameter binds directly to the result of 2168 // applying a conversion function to the argument 2169 // expression, the implicit conversion sequence is a 2170 // user-defined conversion sequence (13.3.3.1.2), with the 2171 // second standard conversion sequence either an identity 2172 // conversion or, if the conversion function returns an 2173 // entity of a type that is a derived class of the parameter 2174 // type, a derived-to-base Conversion. 2175 ICS->ConversionKind = ImplicitConversionSequence::UserDefinedConversion; 2176 ICS->UserDefined.Before = Best->Conversions[0].Standard; 2177 ICS->UserDefined.After = Best->FinalConversion; 2178 ICS->UserDefined.ConversionFunction = Best->Function; 2179 assert(ICS->UserDefined.After.ReferenceBinding && 2180 ICS->UserDefined.After.DirectBinding && 2181 "Expected a direct reference binding!"); 2182 return false; 2183 } else { 2184 // Perform the conversion. 2185 // FIXME: Binding to a subobject of the lvalue is going to require more 2186 // AST annotation than this. 2187 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 2188 } 2189 break; 2190 2191 case OR_Ambiguous: 2192 assert(false && "Ambiguous reference binding conversions not implemented."); 2193 return true; 2194 2195 case OR_No_Viable_Function: 2196 case OR_Deleted: 2197 // There was no suitable conversion, or we found a deleted 2198 // conversion; continue with other checks. 2199 break; 2200 } 2201 } 2202 2203 if (BindsDirectly) { 2204 // C++ [dcl.init.ref]p4: 2205 // [...] In all cases where the reference-related or 2206 // reference-compatible relationship of two types is used to 2207 // establish the validity of a reference binding, and T1 is a 2208 // base class of T2, a program that necessitates such a binding 2209 // is ill-formed if T1 is an inaccessible (clause 11) or 2210 // ambiguous (10.2) base class of T2. 2211 // 2212 // Note that we only check this condition when we're allowed to 2213 // complain about errors, because we should not be checking for 2214 // ambiguity (or inaccessibility) unless the reference binding 2215 // actually happens. 2216 if (DerivedToBase) 2217 return CheckDerivedToBaseConversion(T2, T1, 2218 Init->getSourceRange().getBegin(), 2219 Init->getSourceRange()); 2220 else 2221 return false; 2222 } 2223 2224 // -- Otherwise, the reference shall be to a non-volatile const 2225 // type (i.e., cv1 shall be const), or the reference shall be an 2226 // rvalue reference and the initializer expression shall be an rvalue. 2227 if (!isRValRef && T1.getCVRQualifiers() != QualType::Const) { 2228 if (!ICS) 2229 Diag(Init->getSourceRange().getBegin(), 2230 diag::err_not_reference_to_const_init) 2231 << T1 << (InitLvalue != Expr::LV_Valid? "temporary" : "value") 2232 << T2 << Init->getSourceRange(); 2233 return true; 2234 } 2235 2236 // -- If the initializer expression is an rvalue, with T2 a 2237 // class type, and “cv1 T1” is reference-compatible with 2238 // “cv2 T2,” the reference is bound in one of the 2239 // following ways (the choice is implementation-defined): 2240 // 2241 // -- The reference is bound to the object represented by 2242 // the rvalue (see 3.10) or to a sub-object within that 2243 // object. 2244 // 2245 // -- A temporary of type “cv1 T2” [sic] is created, and 2246 // a constructor is called to copy the entire rvalue 2247 // object into the temporary. The reference is bound to 2248 // the temporary or to a sub-object within the 2249 // temporary. 2250 // 2251 // The constructor that would be used to make the copy 2252 // shall be callable whether or not the copy is actually 2253 // done. 2254 // 2255 // Note that C++0x [dcl.init.ref]p5 takes away this implementation 2256 // freedom, so we will always take the first option and never build 2257 // a temporary in this case. FIXME: We will, however, have to check 2258 // for the presence of a copy constructor in C++98/03 mode. 2259 if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && 2260 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 2261 if (ICS) { 2262 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 2263 ICS->Standard.First = ICK_Identity; 2264 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 2265 ICS->Standard.Third = ICK_Identity; 2266 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 2267 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 2268 ICS->Standard.ReferenceBinding = true; 2269 ICS->Standard.DirectBinding = false; 2270 ICS->Standard.RRefBinding = isRValRef; 2271 ICS->Standard.CopyConstructor = 0; 2272 } else { 2273 // FIXME: Binding to a subobject of the rvalue is going to require more 2274 // AST annotation than this. 2275 ImpCastExprToType(Init, T1, /*isLvalue=*/false); 2276 } 2277 return false; 2278 } 2279 2280 // -- Otherwise, a temporary of type “cv1 T1” is created and 2281 // initialized from the initializer expression using the 2282 // rules for a non-reference copy initialization (8.5). The 2283 // reference is then bound to the temporary. If T1 is 2284 // reference-related to T2, cv1 must be the same 2285 // cv-qualification as, or greater cv-qualification than, 2286 // cv2; otherwise, the program is ill-formed. 2287 if (RefRelationship == Ref_Related) { 2288 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 2289 // we would be reference-compatible or reference-compatible with 2290 // added qualification. But that wasn't the case, so the reference 2291 // initialization fails. 2292 if (!ICS) 2293 Diag(Init->getSourceRange().getBegin(), 2294 diag::err_reference_init_drops_quals) 2295 << T1 << (InitLvalue != Expr::LV_Valid? "temporary" : "value") 2296 << T2 << Init->getSourceRange(); 2297 return true; 2298 } 2299 2300 // If at least one of the types is a class type, the types are not 2301 // related, and we aren't allowed any user conversions, the 2302 // reference binding fails. This case is important for breaking 2303 // recursion, since TryImplicitConversion below will attempt to 2304 // create a temporary through the use of a copy constructor. 2305 if (SuppressUserConversions && RefRelationship == Ref_Incompatible && 2306 (T1->isRecordType() || T2->isRecordType())) { 2307 if (!ICS) 2308 Diag(Init->getSourceRange().getBegin(), 2309 diag::err_typecheck_convert_incompatible) 2310 << DeclType << Init->getType() << "initializing" << Init->getSourceRange(); 2311 return true; 2312 } 2313 2314 // Actually try to convert the initializer to T1. 2315 if (ICS) { 2316 // C++ [over.ics.ref]p2: 2317 // 2318 // When a parameter of reference type is not bound directly to 2319 // an argument expression, the conversion sequence is the one 2320 // required to convert the argument expression to the 2321 // underlying type of the reference according to 2322 // 13.3.3.1. Conceptually, this conversion sequence corresponds 2323 // to copy-initializing a temporary of the underlying type with 2324 // the argument expression. Any difference in top-level 2325 // cv-qualification is subsumed by the initialization itself 2326 // and does not constitute a conversion. 2327 *ICS = TryImplicitConversion(Init, T1, SuppressUserConversions); 2328 // Of course, that's still a reference binding. 2329 if (ICS->ConversionKind == ImplicitConversionSequence::StandardConversion) { 2330 ICS->Standard.ReferenceBinding = true; 2331 ICS->Standard.RRefBinding = isRValRef; 2332 } else if(ICS->ConversionKind == 2333 ImplicitConversionSequence::UserDefinedConversion) { 2334 ICS->UserDefined.After.ReferenceBinding = true; 2335 ICS->UserDefined.After.RRefBinding = isRValRef; 2336 } 2337 return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; 2338 } else { 2339 return PerformImplicitConversion(Init, T1, "initializing"); 2340 } 2341} 2342 2343/// CheckOverloadedOperatorDeclaration - Check whether the declaration 2344/// of this overloaded operator is well-formed. If so, returns false; 2345/// otherwise, emits appropriate diagnostics and returns true. 2346bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) { 2347 assert(FnDecl && FnDecl->isOverloadedOperator() && 2348 "Expected an overloaded operator declaration"); 2349 2350 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator(); 2351 2352 // C++ [over.oper]p5: 2353 // The allocation and deallocation functions, operator new, 2354 // operator new[], operator delete and operator delete[], are 2355 // described completely in 3.7.3. The attributes and restrictions 2356 // found in the rest of this subclause do not apply to them unless 2357 // explicitly stated in 3.7.3. 2358 // FIXME: Write a separate routine for checking this. For now, just allow it. 2359 if (Op == OO_New || Op == OO_Array_New || 2360 Op == OO_Delete || Op == OO_Array_Delete) 2361 return false; 2362 2363 // C++ [over.oper]p6: 2364 // An operator function shall either be a non-static member 2365 // function or be a non-member function and have at least one 2366 // parameter whose type is a class, a reference to a class, an 2367 // enumeration, or a reference to an enumeration. 2368 if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl)) { 2369 if (MethodDecl->isStatic()) 2370 return Diag(FnDecl->getLocation(), 2371 diag::err_operator_overload_static) << FnDecl->getDeclName(); 2372 } else { 2373 bool ClassOrEnumParam = false; 2374 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(), 2375 ParamEnd = FnDecl->param_end(); 2376 Param != ParamEnd; ++Param) { 2377 QualType ParamType = (*Param)->getType().getNonReferenceType(); 2378 if (ParamType->isRecordType() || ParamType->isEnumeralType()) { 2379 ClassOrEnumParam = true; 2380 break; 2381 } 2382 } 2383 2384 if (!ClassOrEnumParam) 2385 return Diag(FnDecl->getLocation(), 2386 diag::err_operator_overload_needs_class_or_enum) 2387 << FnDecl->getDeclName(); 2388 } 2389 2390 // C++ [over.oper]p8: 2391 // An operator function cannot have default arguments (8.3.6), 2392 // except where explicitly stated below. 2393 // 2394 // Only the function-call operator allows default arguments 2395 // (C++ [over.call]p1). 2396 if (Op != OO_Call) { 2397 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 2398 Param != FnDecl->param_end(); ++Param) { 2399 if ((*Param)->hasUnparsedDefaultArg()) 2400 return Diag((*Param)->getLocation(), 2401 diag::err_operator_overload_default_arg) 2402 << FnDecl->getDeclName(); 2403 else if (Expr *DefArg = (*Param)->getDefaultArg()) 2404 return Diag((*Param)->getLocation(), 2405 diag::err_operator_overload_default_arg) 2406 << FnDecl->getDeclName() << DefArg->getSourceRange(); 2407 } 2408 } 2409 2410 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = { 2411 { false, false, false } 2412#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \ 2413 , { Unary, Binary, MemberOnly } 2414#include "clang/Basic/OperatorKinds.def" 2415 }; 2416 2417 bool CanBeUnaryOperator = OperatorUses[Op][0]; 2418 bool CanBeBinaryOperator = OperatorUses[Op][1]; 2419 bool MustBeMemberOperator = OperatorUses[Op][2]; 2420 2421 // C++ [over.oper]p8: 2422 // [...] Operator functions cannot have more or fewer parameters 2423 // than the number required for the corresponding operator, as 2424 // described in the rest of this subclause. 2425 unsigned NumParams = FnDecl->getNumParams() 2426 + (isa<CXXMethodDecl>(FnDecl)? 1 : 0); 2427 if (Op != OO_Call && 2428 ((NumParams == 1 && !CanBeUnaryOperator) || 2429 (NumParams == 2 && !CanBeBinaryOperator) || 2430 (NumParams < 1) || (NumParams > 2))) { 2431 // We have the wrong number of parameters. 2432 unsigned ErrorKind; 2433 if (CanBeUnaryOperator && CanBeBinaryOperator) { 2434 ErrorKind = 2; // 2 -> unary or binary. 2435 } else if (CanBeUnaryOperator) { 2436 ErrorKind = 0; // 0 -> unary 2437 } else { 2438 assert(CanBeBinaryOperator && 2439 "All non-call overloaded operators are unary or binary!"); 2440 ErrorKind = 1; // 1 -> binary 2441 } 2442 2443 return Diag(FnDecl->getLocation(), diag::err_operator_overload_must_be) 2444 << FnDecl->getDeclName() << NumParams << ErrorKind; 2445 } 2446 2447 // Overloaded operators other than operator() cannot be variadic. 2448 if (Op != OO_Call && 2449 FnDecl->getType()->getAsFunctionProtoType()->isVariadic()) { 2450 return Diag(FnDecl->getLocation(), diag::err_operator_overload_variadic) 2451 << FnDecl->getDeclName(); 2452 } 2453 2454 // Some operators must be non-static member functions. 2455 if (MustBeMemberOperator && !isa<CXXMethodDecl>(FnDecl)) { 2456 return Diag(FnDecl->getLocation(), 2457 diag::err_operator_overload_must_be_member) 2458 << FnDecl->getDeclName(); 2459 } 2460 2461 // C++ [over.inc]p1: 2462 // The user-defined function called operator++ implements the 2463 // prefix and postfix ++ operator. If this function is a member 2464 // function with no parameters, or a non-member function with one 2465 // parameter of class or enumeration type, it defines the prefix 2466 // increment operator ++ for objects of that type. If the function 2467 // is a member function with one parameter (which shall be of type 2468 // int) or a non-member function with two parameters (the second 2469 // of which shall be of type int), it defines the postfix 2470 // increment operator ++ for objects of that type. 2471 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) { 2472 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1); 2473 bool ParamIsInt = false; 2474 if (const BuiltinType *BT = LastParam->getType()->getAsBuiltinType()) 2475 ParamIsInt = BT->getKind() == BuiltinType::Int; 2476 2477 if (!ParamIsInt) 2478 return Diag(LastParam->getLocation(), 2479 diag::err_operator_overload_post_incdec_must_be_int) 2480 << LastParam->getType() << (Op == OO_MinusMinus); 2481 } 2482 2483 // Notify the class if it got an assignment operator. 2484 if (Op == OO_Equal) { 2485 // Would have returned earlier otherwise. 2486 assert(isa<CXXMethodDecl>(FnDecl) && 2487 "Overloaded = not member, but not filtered."); 2488 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 2489 Method->getParent()->addedAssignmentOperator(Context, Method); 2490 } 2491 2492 return false; 2493} 2494 2495/// ActOnStartLinkageSpecification - Parsed the beginning of a C++ 2496/// linkage specification, including the language and (if present) 2497/// the '{'. ExternLoc is the location of the 'extern', LangLoc is 2498/// the location of the language string literal, which is provided 2499/// by Lang/StrSize. LBraceLoc, if valid, provides the location of 2500/// the '{' brace. Otherwise, this linkage specification does not 2501/// have any braces. 2502Sema::DeclPtrTy Sema::ActOnStartLinkageSpecification(Scope *S, 2503 SourceLocation ExternLoc, 2504 SourceLocation LangLoc, 2505 const char *Lang, 2506 unsigned StrSize, 2507 SourceLocation LBraceLoc) { 2508 LinkageSpecDecl::LanguageIDs Language; 2509 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2510 Language = LinkageSpecDecl::lang_c; 2511 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2512 Language = LinkageSpecDecl::lang_cxx; 2513 else { 2514 Diag(LangLoc, diag::err_bad_language); 2515 return DeclPtrTy(); 2516 } 2517 2518 // FIXME: Add all the various semantics of linkage specifications 2519 2520 LinkageSpecDecl *D = LinkageSpecDecl::Create(Context, CurContext, 2521 LangLoc, Language, 2522 LBraceLoc.isValid()); 2523 CurContext->addDecl(Context, D); 2524 PushDeclContext(S, D); 2525 return DeclPtrTy::make(D); 2526} 2527 2528/// ActOnFinishLinkageSpecification - Completely the definition of 2529/// the C++ linkage specification LinkageSpec. If RBraceLoc is 2530/// valid, it's the position of the closing '}' brace in a linkage 2531/// specification that uses braces. 2532Sema::DeclPtrTy Sema::ActOnFinishLinkageSpecification(Scope *S, 2533 DeclPtrTy LinkageSpec, 2534 SourceLocation RBraceLoc) { 2535 if (LinkageSpec) 2536 PopDeclContext(); 2537 return LinkageSpec; 2538} 2539 2540/// \brief Perform semantic analysis for the variable declaration that 2541/// occurs within a C++ catch clause, returning the newly-created 2542/// variable. 2543VarDecl *Sema::BuildExceptionDeclaration(Scope *S, QualType ExDeclType, 2544 IdentifierInfo *Name, 2545 SourceLocation Loc, 2546 SourceRange Range) { 2547 bool Invalid = false; 2548 2549 // Arrays and functions decay. 2550 if (ExDeclType->isArrayType()) 2551 ExDeclType = Context.getArrayDecayedType(ExDeclType); 2552 else if (ExDeclType->isFunctionType()) 2553 ExDeclType = Context.getPointerType(ExDeclType); 2554 2555 // C++ 15.3p1: The exception-declaration shall not denote an incomplete type. 2556 // The exception-declaration shall not denote a pointer or reference to an 2557 // incomplete type, other than [cv] void*. 2558 // N2844 forbids rvalue references. 2559 if(!ExDeclType->isDependentType() && ExDeclType->isRValueReferenceType()) { 2560 Diag(Loc, diag::err_catch_rvalue_ref) << Range; 2561 Invalid = true; 2562 } 2563 2564 QualType BaseType = ExDeclType; 2565 int Mode = 0; // 0 for direct type, 1 for pointer, 2 for reference 2566 unsigned DK = diag::err_catch_incomplete; 2567 if (const PointerType *Ptr = BaseType->getAsPointerType()) { 2568 BaseType = Ptr->getPointeeType(); 2569 Mode = 1; 2570 DK = diag::err_catch_incomplete_ptr; 2571 } else if(const ReferenceType *Ref = BaseType->getAsReferenceType()) { 2572 // For the purpose of error recovery, we treat rvalue refs like lvalue refs. 2573 BaseType = Ref->getPointeeType(); 2574 Mode = 2; 2575 DK = diag::err_catch_incomplete_ref; 2576 } 2577 if (!Invalid && (Mode == 0 || !BaseType->isVoidType()) && 2578 !BaseType->isDependentType() && RequireCompleteType(Loc, BaseType, DK)) 2579 Invalid = true; 2580 2581 if (!Invalid && !ExDeclType->isDependentType() && 2582 RequireNonAbstractType(Loc, ExDeclType, 2583 diag::err_abstract_type_in_decl, 2584 AbstractVariableType)) 2585 Invalid = true; 2586 2587 // FIXME: Need to test for ability to copy-construct and destroy the 2588 // exception variable. 2589 2590 // FIXME: Need to check for abstract classes. 2591 2592 VarDecl *ExDecl = VarDecl::Create(Context, CurContext, Loc, 2593 Name, ExDeclType, VarDecl::None, 2594 Range.getBegin()); 2595 2596 if (Invalid) 2597 ExDecl->setInvalidDecl(); 2598 2599 return ExDecl; 2600} 2601 2602/// ActOnExceptionDeclarator - Parsed the exception-declarator in a C++ catch 2603/// handler. 2604Sema::DeclPtrTy Sema::ActOnExceptionDeclarator(Scope *S, Declarator &D) { 2605 QualType ExDeclType = GetTypeForDeclarator(D, S); 2606 2607 bool Invalid = D.isInvalidType(); 2608 IdentifierInfo *II = D.getIdentifier(); 2609 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2610 // The scope should be freshly made just for us. There is just no way 2611 // it contains any previous declaration. 2612 assert(!S->isDeclScope(DeclPtrTy::make(PrevDecl))); 2613 if (PrevDecl->isTemplateParameter()) { 2614 // Maybe we will complain about the shadowed template parameter. 2615 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2616 } 2617 } 2618 2619 if (D.getCXXScopeSpec().isSet() && !Invalid) { 2620 Diag(D.getIdentifierLoc(), diag::err_qualified_catch_declarator) 2621 << D.getCXXScopeSpec().getRange(); 2622 Invalid = true; 2623 } 2624 2625 VarDecl *ExDecl = BuildExceptionDeclaration(S, ExDeclType, 2626 D.getIdentifier(), 2627 D.getIdentifierLoc(), 2628 D.getDeclSpec().getSourceRange()); 2629 2630 if (Invalid) 2631 ExDecl->setInvalidDecl(); 2632 2633 // Add the exception declaration into this scope. 2634 if (II) 2635 PushOnScopeChains(ExDecl, S); 2636 else 2637 CurContext->addDecl(Context, ExDecl); 2638 2639 ProcessDeclAttributes(ExDecl, D); 2640 return DeclPtrTy::make(ExDecl); 2641} 2642 2643Sema::DeclPtrTy Sema::ActOnStaticAssertDeclaration(SourceLocation AssertLoc, 2644 ExprArg assertexpr, 2645 ExprArg assertmessageexpr) { 2646 Expr *AssertExpr = (Expr *)assertexpr.get(); 2647 StringLiteral *AssertMessage = 2648 cast<StringLiteral>((Expr *)assertmessageexpr.get()); 2649 2650 if (!AssertExpr->isTypeDependent() && !AssertExpr->isValueDependent()) { 2651 llvm::APSInt Value(32); 2652 if (!AssertExpr->isIntegerConstantExpr(Value, Context)) { 2653 Diag(AssertLoc, diag::err_static_assert_expression_is_not_constant) << 2654 AssertExpr->getSourceRange(); 2655 return DeclPtrTy(); 2656 } 2657 2658 if (Value == 0) { 2659 std::string str(AssertMessage->getStrData(), 2660 AssertMessage->getByteLength()); 2661 Diag(AssertLoc, diag::err_static_assert_failed) 2662 << str << AssertExpr->getSourceRange(); 2663 } 2664 } 2665 2666 assertexpr.release(); 2667 assertmessageexpr.release(); 2668 Decl *Decl = StaticAssertDecl::Create(Context, CurContext, AssertLoc, 2669 AssertExpr, AssertMessage); 2670 2671 CurContext->addDecl(Context, Decl); 2672 return DeclPtrTy::make(Decl); 2673} 2674 2675bool Sema::ActOnFriendDecl(Scope *S, SourceLocation FriendLoc, DeclPtrTy Dcl) { 2676 if (!(S->getFlags() & Scope::ClassScope)) { 2677 Diag(FriendLoc, diag::err_friend_decl_outside_class); 2678 return true; 2679 } 2680 2681 return false; 2682} 2683 2684void Sema::SetDeclDeleted(DeclPtrTy dcl, SourceLocation DelLoc) { 2685 Decl *Dcl = dcl.getAs<Decl>(); 2686 FunctionDecl *Fn = dyn_cast<FunctionDecl>(Dcl); 2687 if (!Fn) { 2688 Diag(DelLoc, diag::err_deleted_non_function); 2689 return; 2690 } 2691 if (const FunctionDecl *Prev = Fn->getPreviousDeclaration()) { 2692 Diag(DelLoc, diag::err_deleted_decl_not_first); 2693 Diag(Prev->getLocation(), diag::note_previous_declaration); 2694 // If the declaration wasn't the first, we delete the function anyway for 2695 // recovery. 2696 } 2697 Fn->setDeleted(); 2698} 2699 2700static void SearchForReturnInStmt(Sema &Self, Stmt *S) { 2701 for (Stmt::child_iterator CI = S->child_begin(), E = S->child_end(); CI != E; 2702 ++CI) { 2703 Stmt *SubStmt = *CI; 2704 if (!SubStmt) 2705 continue; 2706 if (isa<ReturnStmt>(SubStmt)) 2707 Self.Diag(SubStmt->getSourceRange().getBegin(), 2708 diag::err_return_in_constructor_handler); 2709 if (!isa<Expr>(SubStmt)) 2710 SearchForReturnInStmt(Self, SubStmt); 2711 } 2712} 2713 2714void Sema::DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock) { 2715 for (unsigned I = 0, E = TryBlock->getNumHandlers(); I != E; ++I) { 2716 CXXCatchStmt *Handler = TryBlock->getHandler(I); 2717 SearchForReturnInStmt(*this, Handler); 2718 } 2719} 2720 2721bool Sema::CheckOverridingFunctionReturnType(const CXXMethodDecl *New, 2722 const CXXMethodDecl *Old) { 2723 QualType NewTy = New->getType()->getAsFunctionType()->getResultType(); 2724 QualType OldTy = Old->getType()->getAsFunctionType()->getResultType(); 2725 2726 QualType CNewTy = Context.getCanonicalType(NewTy); 2727 QualType COldTy = Context.getCanonicalType(OldTy); 2728 2729 if (CNewTy == COldTy && 2730 CNewTy.getCVRQualifiers() == COldTy.getCVRQualifiers()) 2731 return false; 2732 2733 // Check if the return types are covariant 2734 QualType NewClassTy, OldClassTy; 2735 2736 /// Both types must be pointers or references to classes. 2737 if (PointerType *NewPT = dyn_cast<PointerType>(NewTy)) { 2738 if (PointerType *OldPT = dyn_cast<PointerType>(OldTy)) { 2739 NewClassTy = NewPT->getPointeeType(); 2740 OldClassTy = OldPT->getPointeeType(); 2741 } 2742 } else if (ReferenceType *NewRT = dyn_cast<ReferenceType>(NewTy)) { 2743 if (ReferenceType *OldRT = dyn_cast<ReferenceType>(OldTy)) { 2744 NewClassTy = NewRT->getPointeeType(); 2745 OldClassTy = OldRT->getPointeeType(); 2746 } 2747 } 2748 2749 // The return types aren't either both pointers or references to a class type. 2750 if (NewClassTy.isNull()) { 2751 Diag(New->getLocation(), 2752 diag::err_different_return_type_for_overriding_virtual_function) 2753 << New->getDeclName() << NewTy << OldTy; 2754 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2755 2756 return true; 2757 } 2758 2759 if (NewClassTy.getUnqualifiedType() != OldClassTy.getUnqualifiedType()) { 2760 // Check if the new class derives from the old class. 2761 if (!IsDerivedFrom(NewClassTy, OldClassTy)) { 2762 Diag(New->getLocation(), 2763 diag::err_covariant_return_not_derived) 2764 << New->getDeclName() << NewTy << OldTy; 2765 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2766 return true; 2767 } 2768 2769 // Check if we the conversion from derived to base is valid. 2770 if (CheckDerivedToBaseConversion(NewClassTy, OldClassTy, 2771 diag::err_covariant_return_inaccessible_base, 2772 diag::err_covariant_return_ambiguous_derived_to_base_conv, 2773 // FIXME: Should this point to the return type? 2774 New->getLocation(), SourceRange(), New->getDeclName())) { 2775 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2776 return true; 2777 } 2778 } 2779 2780 // The qualifiers of the return types must be the same. 2781 if (CNewTy.getCVRQualifiers() != COldTy.getCVRQualifiers()) { 2782 Diag(New->getLocation(), 2783 diag::err_covariant_return_type_different_qualifications) 2784 << New->getDeclName() << NewTy << OldTy; 2785 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2786 return true; 2787 }; 2788 2789 2790 // The new class type must have the same or less qualifiers as the old type. 2791 if (NewClassTy.isMoreQualifiedThan(OldClassTy)) { 2792 Diag(New->getLocation(), 2793 diag::err_covariant_return_type_class_type_more_qualified) 2794 << New->getDeclName() << NewTy << OldTy; 2795 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2796 return true; 2797 }; 2798 2799 return false; 2800} 2801