SemaDeclCXX.cpp revision 9cdda0cf8528e3d595be9bfa002f0450074beb4d
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 UnparsedDefaultArgLocs.erase(Param); 112 113 ExprOwningPtr<Expr> DefaultArg(this, defarg.takeAs<Expr>()); 114 QualType ParamType = Param->getType(); 115 116 // Default arguments are only permitted in C++ 117 if (!getLangOptions().CPlusPlus) { 118 Diag(EqualLoc, diag::err_param_default_argument) 119 << DefaultArg->getSourceRange(); 120 Param->setInvalidDecl(); 121 return; 122 } 123 124 // C++ [dcl.fct.default]p5 125 // A default argument expression is implicitly converted (clause 126 // 4) to the parameter type. The default argument expression has 127 // the same semantic constraints as the initializer expression in 128 // a declaration of a variable of the parameter type, using the 129 // copy-initialization semantics (8.5). 130 Expr *DefaultArgPtr = DefaultArg.get(); 131 bool DefaultInitFailed = CheckInitializerTypes(DefaultArgPtr, ParamType, 132 EqualLoc, 133 Param->getDeclName(), 134 /*DirectInit=*/false); 135 if (DefaultArgPtr != DefaultArg.get()) { 136 DefaultArg.take(); 137 DefaultArg.reset(DefaultArgPtr); 138 } 139 if (DefaultInitFailed) { 140 return; 141 } 142 143 // Check that the default argument is well-formed 144 CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg.get(), this); 145 if (DefaultArgChecker.Visit(DefaultArg.get())) { 146 Param->setInvalidDecl(); 147 return; 148 } 149 150 DefaultArgPtr = MaybeCreateCXXExprWithTemporaries(DefaultArg.take(), 151 /*DestroyTemps=*/false); 152 153 // Okay: add the default argument to the parameter 154 Param->setDefaultArg(DefaultArgPtr); 155} 156 157/// ActOnParamUnparsedDefaultArgument - We've seen a default 158/// argument for a function parameter, but we can't parse it yet 159/// because we're inside a class definition. Note that this default 160/// argument will be parsed later. 161void Sema::ActOnParamUnparsedDefaultArgument(DeclPtrTy param, 162 SourceLocation EqualLoc, 163 SourceLocation ArgLoc) { 164 ParmVarDecl *Param = cast<ParmVarDecl>(param.getAs<Decl>()); 165 if (Param) 166 Param->setUnparsedDefaultArg(); 167 168 UnparsedDefaultArgLocs[Param] = ArgLoc; 169} 170 171/// ActOnParamDefaultArgumentError - Parsing or semantic analysis of 172/// the default argument for the parameter param failed. 173void Sema::ActOnParamDefaultArgumentError(DeclPtrTy param) { 174 ParmVarDecl *Param = cast<ParmVarDecl>(param.getAs<Decl>()); 175 176 Param->setInvalidDecl(); 177 178 UnparsedDefaultArgLocs.erase(Param); 179} 180 181/// CheckExtraCXXDefaultArguments - Check for any extra default 182/// arguments in the declarator, which is not a function declaration 183/// or definition and therefore is not permitted to have default 184/// arguments. This routine should be invoked for every declarator 185/// that is not a function declaration or definition. 186void Sema::CheckExtraCXXDefaultArguments(Declarator &D) { 187 // C++ [dcl.fct.default]p3 188 // A default argument expression shall be specified only in the 189 // parameter-declaration-clause of a function declaration or in a 190 // template-parameter (14.1). It shall not be specified for a 191 // parameter pack. If it is specified in a 192 // parameter-declaration-clause, it shall not occur within a 193 // declarator or abstract-declarator of a parameter-declaration. 194 for (unsigned i = 0, e = D.getNumTypeObjects(); i != e; ++i) { 195 DeclaratorChunk &chunk = D.getTypeObject(i); 196 if (chunk.Kind == DeclaratorChunk::Function) { 197 for (unsigned argIdx = 0, e = chunk.Fun.NumArgs; argIdx != e; ++argIdx) { 198 ParmVarDecl *Param = 199 cast<ParmVarDecl>(chunk.Fun.ArgInfo[argIdx].Param.getAs<Decl>()); 200 if (Param->hasUnparsedDefaultArg()) { 201 CachedTokens *Toks = chunk.Fun.ArgInfo[argIdx].DefaultArgTokens; 202 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc) 203 << SourceRange((*Toks)[1].getLocation(), Toks->back().getLocation()); 204 delete Toks; 205 chunk.Fun.ArgInfo[argIdx].DefaultArgTokens = 0; 206 } else if (Param->getDefaultArg()) { 207 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc) 208 << Param->getDefaultArg()->getSourceRange(); 209 Param->setDefaultArg(0); 210 } 211 } 212 } 213 } 214} 215 216// MergeCXXFunctionDecl - Merge two declarations of the same C++ 217// function, once we already know that they have the same 218// type. Subroutine of MergeFunctionDecl. Returns true if there was an 219// error, false otherwise. 220bool Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old) { 221 bool Invalid = false; 222 223 // C++ [dcl.fct.default]p4: 224 // 225 // For non-template functions, default arguments can be added in 226 // later declarations of a function in the same 227 // scope. Declarations in different scopes have completely 228 // distinct sets of default arguments. That is, declarations in 229 // inner scopes do not acquire default arguments from 230 // declarations in outer scopes, and vice versa. In a given 231 // function declaration, all parameters subsequent to a 232 // parameter with a default argument shall have default 233 // arguments supplied in this or previous declarations. A 234 // default argument shall not be redefined by a later 235 // declaration (not even to the same value). 236 for (unsigned p = 0, NumParams = Old->getNumParams(); p < NumParams; ++p) { 237 ParmVarDecl *OldParam = Old->getParamDecl(p); 238 ParmVarDecl *NewParam = New->getParamDecl(p); 239 240 if(OldParam->getDefaultArg() && NewParam->getDefaultArg()) { 241 Diag(NewParam->getLocation(), 242 diag::err_param_default_argument_redefinition) 243 << NewParam->getDefaultArg()->getSourceRange(); 244 Diag(OldParam->getLocation(), diag::note_previous_definition); 245 Invalid = true; 246 } else if (OldParam->getDefaultArg()) { 247 // Merge the old default argument into the new parameter 248 NewParam->setDefaultArg(OldParam->getDefaultArg()); 249 } 250 } 251 252 return Invalid; 253} 254 255/// CheckCXXDefaultArguments - Verify that the default arguments for a 256/// function declaration are well-formed according to C++ 257/// [dcl.fct.default]. 258void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) { 259 unsigned NumParams = FD->getNumParams(); 260 unsigned p; 261 262 // Find first parameter with a default argument 263 for (p = 0; p < NumParams; ++p) { 264 ParmVarDecl *Param = FD->getParamDecl(p); 265 if (Param->getDefaultArg()) 266 break; 267 } 268 269 // C++ [dcl.fct.default]p4: 270 // In a given function declaration, all parameters 271 // subsequent to a parameter with a default argument shall 272 // have default arguments supplied in this or previous 273 // declarations. A default argument shall not be redefined 274 // by a later declaration (not even to the same value). 275 unsigned LastMissingDefaultArg = 0; 276 for(; p < NumParams; ++p) { 277 ParmVarDecl *Param = FD->getParamDecl(p); 278 if (!Param->getDefaultArg()) { 279 if (Param->isInvalidDecl()) 280 /* We already complained about this parameter. */; 281 else if (Param->getIdentifier()) 282 Diag(Param->getLocation(), 283 diag::err_param_default_argument_missing_name) 284 << Param->getIdentifier(); 285 else 286 Diag(Param->getLocation(), 287 diag::err_param_default_argument_missing); 288 289 LastMissingDefaultArg = p; 290 } 291 } 292 293 if (LastMissingDefaultArg > 0) { 294 // Some default arguments were missing. Clear out all of the 295 // default arguments up to (and including) the last missing 296 // default argument, so that we leave the function parameters 297 // in a semantically valid state. 298 for (p = 0; p <= LastMissingDefaultArg; ++p) { 299 ParmVarDecl *Param = FD->getParamDecl(p); 300 if (Param->hasDefaultArg()) { 301 if (!Param->hasUnparsedDefaultArg()) 302 Param->getDefaultArg()->Destroy(Context); 303 Param->setDefaultArg(0); 304 } 305 } 306 } 307} 308 309/// isCurrentClassName - Determine whether the identifier II is the 310/// name of the class type currently being defined. In the case of 311/// nested classes, this will only return true if II is the name of 312/// the innermost class. 313bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *, 314 const CXXScopeSpec *SS) { 315 CXXRecordDecl *CurDecl; 316 if (SS && SS->isSet() && !SS->isInvalid()) { 317 DeclContext *DC = computeDeclContext(*SS); 318 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC); 319 } else 320 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 321 322 if (CurDecl) 323 return &II == CurDecl->getIdentifier(); 324 else 325 return false; 326} 327 328/// \brief Check the validity of a C++ base class specifier. 329/// 330/// \returns a new CXXBaseSpecifier if well-formed, emits diagnostics 331/// and returns NULL otherwise. 332CXXBaseSpecifier * 333Sema::CheckBaseSpecifier(CXXRecordDecl *Class, 334 SourceRange SpecifierRange, 335 bool Virtual, AccessSpecifier Access, 336 QualType BaseType, 337 SourceLocation BaseLoc) { 338 // C++ [class.union]p1: 339 // A union shall not have base classes. 340 if (Class->isUnion()) { 341 Diag(Class->getLocation(), diag::err_base_clause_on_union) 342 << SpecifierRange; 343 return 0; 344 } 345 346 if (BaseType->isDependentType()) 347 return new CXXBaseSpecifier(SpecifierRange, Virtual, 348 Class->getTagKind() == RecordDecl::TK_class, 349 Access, BaseType); 350 351 // Base specifiers must be record types. 352 if (!BaseType->isRecordType()) { 353 Diag(BaseLoc, diag::err_base_must_be_class) << SpecifierRange; 354 return 0; 355 } 356 357 // C++ [class.union]p1: 358 // A union shall not be used as a base class. 359 if (BaseType->isUnionType()) { 360 Diag(BaseLoc, diag::err_union_as_base_class) << SpecifierRange; 361 return 0; 362 } 363 364 // C++ [class.derived]p2: 365 // The class-name in a base-specifier shall not be an incompletely 366 // defined class. 367 if (RequireCompleteType(BaseLoc, BaseType, diag::err_incomplete_base_class, 368 SpecifierRange)) 369 return 0; 370 371 // If the base class is polymorphic, the new one is, too. 372 RecordDecl *BaseDecl = BaseType->getAsRecordType()->getDecl(); 373 assert(BaseDecl && "Record type has no declaration"); 374 BaseDecl = BaseDecl->getDefinition(Context); 375 assert(BaseDecl && "Base type is not incomplete, but has no definition"); 376 if (cast<CXXRecordDecl>(BaseDecl)->isPolymorphic()) 377 Class->setPolymorphic(true); 378 379 // C++ [dcl.init.aggr]p1: 380 // An aggregate is [...] a class with [...] no base classes [...]. 381 Class->setAggregate(false); 382 Class->setPOD(false); 383 384 if (Virtual) { 385 // C++ [class.ctor]p5: 386 // A constructor is trivial if its class has no virtual base classes. 387 Class->setHasTrivialConstructor(false); 388 } else { 389 // C++ [class.ctor]p5: 390 // A constructor is trivial if all the direct base classes of its 391 // class have trivial constructors. 392 Class->setHasTrivialConstructor(cast<CXXRecordDecl>(BaseDecl)-> 393 hasTrivialConstructor()); 394 } 395 396 // C++ [class.ctor]p3: 397 // A destructor is trivial if all the direct base classes of its class 398 // have trivial destructors. 399 Class->setHasTrivialDestructor(cast<CXXRecordDecl>(BaseDecl)-> 400 hasTrivialDestructor()); 401 402 // Create the base specifier. 403 // FIXME: Allocate via ASTContext? 404 return new CXXBaseSpecifier(SpecifierRange, Virtual, 405 Class->getTagKind() == RecordDecl::TK_class, 406 Access, BaseType); 407} 408 409/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is 410/// one entry in the base class list of a class specifier, for 411/// example: 412/// class foo : public bar, virtual private baz { 413/// 'public bar' and 'virtual private baz' are each base-specifiers. 414Sema::BaseResult 415Sema::ActOnBaseSpecifier(DeclPtrTy classdecl, SourceRange SpecifierRange, 416 bool Virtual, AccessSpecifier Access, 417 TypeTy *basetype, SourceLocation BaseLoc) { 418 AdjustDeclIfTemplate(classdecl); 419 CXXRecordDecl *Class = cast<CXXRecordDecl>(classdecl.getAs<Decl>()); 420 QualType BaseType = QualType::getFromOpaquePtr(basetype); 421 if (CXXBaseSpecifier *BaseSpec = CheckBaseSpecifier(Class, SpecifierRange, 422 Virtual, Access, 423 BaseType, BaseLoc)) 424 return BaseSpec; 425 426 return true; 427} 428 429/// \brief Performs the actual work of attaching the given base class 430/// specifiers to a C++ class. 431bool Sema::AttachBaseSpecifiers(CXXRecordDecl *Class, CXXBaseSpecifier **Bases, 432 unsigned NumBases) { 433 if (NumBases == 0) 434 return false; 435 436 // Used to keep track of which base types we have already seen, so 437 // that we can properly diagnose redundant direct base types. Note 438 // that the key is always the unqualified canonical type of the base 439 // class. 440 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes; 441 442 // Copy non-redundant base specifiers into permanent storage. 443 unsigned NumGoodBases = 0; 444 bool Invalid = false; 445 for (unsigned idx = 0; idx < NumBases; ++idx) { 446 QualType NewBaseType 447 = Context.getCanonicalType(Bases[idx]->getType()); 448 NewBaseType = NewBaseType.getUnqualifiedType(); 449 450 if (KnownBaseTypes[NewBaseType]) { 451 // C++ [class.mi]p3: 452 // A class shall not be specified as a direct base class of a 453 // derived class more than once. 454 Diag(Bases[idx]->getSourceRange().getBegin(), 455 diag::err_duplicate_base_class) 456 << KnownBaseTypes[NewBaseType]->getType() 457 << Bases[idx]->getSourceRange(); 458 459 // Delete the duplicate base class specifier; we're going to 460 // overwrite its pointer later. 461 delete Bases[idx]; 462 463 Invalid = true; 464 } else { 465 // Okay, add this new base class. 466 KnownBaseTypes[NewBaseType] = Bases[idx]; 467 Bases[NumGoodBases++] = Bases[idx]; 468 } 469 } 470 471 // Attach the remaining base class specifiers to the derived class. 472 Class->setBases(Bases, NumGoodBases); 473 474 // Delete the remaining (good) base class specifiers, since their 475 // data has been copied into the CXXRecordDecl. 476 for (unsigned idx = 0; idx < NumGoodBases; ++idx) 477 delete Bases[idx]; 478 479 return Invalid; 480} 481 482/// ActOnBaseSpecifiers - Attach the given base specifiers to the 483/// class, after checking whether there are any duplicate base 484/// classes. 485void Sema::ActOnBaseSpecifiers(DeclPtrTy ClassDecl, BaseTy **Bases, 486 unsigned NumBases) { 487 if (!ClassDecl || !Bases || !NumBases) 488 return; 489 490 AdjustDeclIfTemplate(ClassDecl); 491 AttachBaseSpecifiers(cast<CXXRecordDecl>(ClassDecl.getAs<Decl>()), 492 (CXXBaseSpecifier**)(Bases), NumBases); 493} 494 495//===----------------------------------------------------------------------===// 496// C++ class member Handling 497//===----------------------------------------------------------------------===// 498 499/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member 500/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the 501/// bitfield width if there is one and 'InitExpr' specifies the initializer if 502/// any. 503Sema::DeclPtrTy 504Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D, 505 ExprTy *BW, ExprTy *InitExpr, bool Deleted) { 506 const DeclSpec &DS = D.getDeclSpec(); 507 DeclarationName Name = GetNameForDeclarator(D); 508 Expr *BitWidth = static_cast<Expr*>(BW); 509 Expr *Init = static_cast<Expr*>(InitExpr); 510 SourceLocation Loc = D.getIdentifierLoc(); 511 512 bool isFunc = D.isFunctionDeclarator(); 513 514 // C++ 9.2p6: A member shall not be declared to have automatic storage 515 // duration (auto, register) or with the extern storage-class-specifier. 516 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class 517 // data members and cannot be applied to names declared const or static, 518 // and cannot be applied to reference members. 519 switch (DS.getStorageClassSpec()) { 520 case DeclSpec::SCS_unspecified: 521 case DeclSpec::SCS_typedef: 522 case DeclSpec::SCS_static: 523 // FALL THROUGH. 524 break; 525 case DeclSpec::SCS_mutable: 526 if (isFunc) { 527 if (DS.getStorageClassSpecLoc().isValid()) 528 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_function); 529 else 530 Diag(DS.getThreadSpecLoc(), diag::err_mutable_function); 531 532 // FIXME: It would be nicer if the keyword was ignored only for this 533 // declarator. Otherwise we could get follow-up errors. 534 D.getMutableDeclSpec().ClearStorageClassSpecs(); 535 } else { 536 QualType T = GetTypeForDeclarator(D, S); 537 diag::kind err = static_cast<diag::kind>(0); 538 if (T->isReferenceType()) 539 err = diag::err_mutable_reference; 540 else if (T.isConstQualified()) 541 err = diag::err_mutable_const; 542 if (err != 0) { 543 if (DS.getStorageClassSpecLoc().isValid()) 544 Diag(DS.getStorageClassSpecLoc(), err); 545 else 546 Diag(DS.getThreadSpecLoc(), err); 547 // FIXME: It would be nicer if the keyword was ignored only for this 548 // declarator. Otherwise we could get follow-up errors. 549 D.getMutableDeclSpec().ClearStorageClassSpecs(); 550 } 551 } 552 break; 553 default: 554 if (DS.getStorageClassSpecLoc().isValid()) 555 Diag(DS.getStorageClassSpecLoc(), 556 diag::err_storageclass_invalid_for_member); 557 else 558 Diag(DS.getThreadSpecLoc(), diag::err_storageclass_invalid_for_member); 559 D.getMutableDeclSpec().ClearStorageClassSpecs(); 560 } 561 562 if (!isFunc && 563 D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_typename && 564 D.getNumTypeObjects() == 0) { 565 // Check also for this case: 566 // 567 // typedef int f(); 568 // f a; 569 // 570 QualType TDType = QualType::getFromOpaquePtr(DS.getTypeRep()); 571 isFunc = TDType->isFunctionType(); 572 } 573 574 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified || 575 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) && 576 !isFunc); 577 578 Decl *Member; 579 if (isInstField) { 580 Member = HandleField(S, cast<CXXRecordDecl>(CurContext), Loc, D, BitWidth, 581 AS); 582 assert(Member && "HandleField never returns null"); 583 } else { 584 Member = ActOnDeclarator(S, D).getAs<Decl>(); 585 if (!Member) { 586 if (BitWidth) DeleteExpr(BitWidth); 587 return DeclPtrTy(); 588 } 589 590 // Non-instance-fields can't have a bitfield. 591 if (BitWidth) { 592 if (Member->isInvalidDecl()) { 593 // don't emit another diagnostic. 594 } else if (isa<VarDecl>(Member)) { 595 // C++ 9.6p3: A bit-field shall not be a static member. 596 // "static member 'A' cannot be a bit-field" 597 Diag(Loc, diag::err_static_not_bitfield) 598 << Name << BitWidth->getSourceRange(); 599 } else if (isa<TypedefDecl>(Member)) { 600 // "typedef member 'x' cannot be a bit-field" 601 Diag(Loc, diag::err_typedef_not_bitfield) 602 << Name << BitWidth->getSourceRange(); 603 } else { 604 // A function typedef ("typedef int f(); f a;"). 605 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 606 Diag(Loc, diag::err_not_integral_type_bitfield) 607 << Name << cast<ValueDecl>(Member)->getType() 608 << BitWidth->getSourceRange(); 609 } 610 611 DeleteExpr(BitWidth); 612 BitWidth = 0; 613 Member->setInvalidDecl(); 614 } 615 616 Member->setAccess(AS); 617 } 618 619 assert((Name || isInstField) && "No identifier for non-field ?"); 620 621 if (Init) 622 AddInitializerToDecl(DeclPtrTy::make(Member), ExprArg(*this, Init), false); 623 if (Deleted) // FIXME: Source location is not very good. 624 SetDeclDeleted(DeclPtrTy::make(Member), D.getSourceRange().getBegin()); 625 626 if (isInstField) { 627 FieldCollector->Add(cast<FieldDecl>(Member)); 628 return DeclPtrTy(); 629 } 630 return DeclPtrTy::make(Member); 631} 632 633/// ActOnMemInitializer - Handle a C++ member initializer. 634Sema::MemInitResult 635Sema::ActOnMemInitializer(DeclPtrTy ConstructorD, 636 Scope *S, 637 IdentifierInfo *MemberOrBase, 638 SourceLocation IdLoc, 639 SourceLocation LParenLoc, 640 ExprTy **Args, unsigned NumArgs, 641 SourceLocation *CommaLocs, 642 SourceLocation RParenLoc) { 643 CXXConstructorDecl *Constructor 644 = dyn_cast<CXXConstructorDecl>(ConstructorD.getAs<Decl>()); 645 if (!Constructor) { 646 // The user wrote a constructor initializer on a function that is 647 // not a C++ constructor. Ignore the error for now, because we may 648 // have more member initializers coming; we'll diagnose it just 649 // once in ActOnMemInitializers. 650 return true; 651 } 652 653 CXXRecordDecl *ClassDecl = Constructor->getParent(); 654 655 // C++ [class.base.init]p2: 656 // Names in a mem-initializer-id are looked up in the scope of the 657 // constructor’s class and, if not found in that scope, are looked 658 // up in the scope containing the constructor’s 659 // definition. [Note: if the constructor’s class contains a member 660 // with the same name as a direct or virtual base class of the 661 // class, a mem-initializer-id naming the member or base class and 662 // composed of a single identifier refers to the class member. A 663 // mem-initializer-id for the hidden base class may be specified 664 // using a qualified name. ] 665 // Look for a member, first. 666 FieldDecl *Member = 0; 667 DeclContext::lookup_result Result 668 = ClassDecl->lookup(Context, MemberOrBase); 669 if (Result.first != Result.second) 670 Member = dyn_cast<FieldDecl>(*Result.first); 671 672 // FIXME: Handle members of an anonymous union. 673 674 if (Member) { 675 // FIXME: Perform direct initialization of the member. 676 return new CXXBaseOrMemberInitializer(Member, (Expr **)Args, NumArgs); 677 } 678 679 // It didn't name a member, so see if it names a class. 680 TypeTy *BaseTy = getTypeName(*MemberOrBase, IdLoc, S, 0/*SS*/); 681 if (!BaseTy) 682 return Diag(IdLoc, diag::err_mem_init_not_member_or_class) 683 << MemberOrBase << SourceRange(IdLoc, RParenLoc); 684 685 QualType BaseType = QualType::getFromOpaquePtr(BaseTy); 686 if (!BaseType->isRecordType()) 687 return Diag(IdLoc, diag::err_base_init_does_not_name_class) 688 << BaseType << SourceRange(IdLoc, RParenLoc); 689 690 // C++ [class.base.init]p2: 691 // [...] Unless the mem-initializer-id names a nonstatic data 692 // member of the constructor’s class or a direct or virtual base 693 // of that class, the mem-initializer is ill-formed. A 694 // mem-initializer-list can initialize a base class using any 695 // name that denotes that base class type. 696 697 // First, check for a direct base class. 698 const CXXBaseSpecifier *DirectBaseSpec = 0; 699 for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin(); 700 Base != ClassDecl->bases_end(); ++Base) { 701 if (Context.getCanonicalType(BaseType).getUnqualifiedType() == 702 Context.getCanonicalType(Base->getType()).getUnqualifiedType()) { 703 // We found a direct base of this type. That's what we're 704 // initializing. 705 DirectBaseSpec = &*Base; 706 break; 707 } 708 } 709 710 // Check for a virtual base class. 711 // FIXME: We might be able to short-circuit this if we know in advance that 712 // there are no virtual bases. 713 const CXXBaseSpecifier *VirtualBaseSpec = 0; 714 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) { 715 // We haven't found a base yet; search the class hierarchy for a 716 // virtual base class. 717 BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 718 /*DetectVirtual=*/false); 719 if (IsDerivedFrom(Context.getTypeDeclType(ClassDecl), BaseType, Paths)) { 720 for (BasePaths::paths_iterator Path = Paths.begin(); 721 Path != Paths.end(); ++Path) { 722 if (Path->back().Base->isVirtual()) { 723 VirtualBaseSpec = Path->back().Base; 724 break; 725 } 726 } 727 } 728 } 729 730 // C++ [base.class.init]p2: 731 // If a mem-initializer-id is ambiguous because it designates both 732 // a direct non-virtual base class and an inherited virtual base 733 // class, the mem-initializer is ill-formed. 734 if (DirectBaseSpec && VirtualBaseSpec) 735 return Diag(IdLoc, diag::err_base_init_direct_and_virtual) 736 << MemberOrBase << SourceRange(IdLoc, RParenLoc); 737 738 return new CXXBaseOrMemberInitializer(BaseType, (Expr **)Args, NumArgs); 739} 740 741void Sema::ActOnMemInitializers(DeclPtrTy ConstructorDecl, 742 SourceLocation ColonLoc, 743 MemInitTy **MemInits, unsigned NumMemInits) { 744 CXXConstructorDecl *Constructor = 745 dyn_cast<CXXConstructorDecl>(ConstructorDecl.getAs<Decl>()); 746 747 if (!Constructor) { 748 Diag(ColonLoc, diag::err_only_constructors_take_base_inits); 749 return; 750 } 751} 752 753namespace { 754 /// PureVirtualMethodCollector - traverses a class and its superclasses 755 /// and determines if it has any pure virtual methods. 756 class VISIBILITY_HIDDEN PureVirtualMethodCollector { 757 ASTContext &Context; 758 759 public: 760 typedef llvm::SmallVector<const CXXMethodDecl*, 8> MethodList; 761 762 private: 763 MethodList Methods; 764 765 void Collect(const CXXRecordDecl* RD, MethodList& Methods); 766 767 public: 768 PureVirtualMethodCollector(ASTContext &Ctx, const CXXRecordDecl* RD) 769 : Context(Ctx) { 770 771 MethodList List; 772 Collect(RD, List); 773 774 // Copy the temporary list to methods, and make sure to ignore any 775 // null entries. 776 for (size_t i = 0, e = List.size(); i != e; ++i) { 777 if (List[i]) 778 Methods.push_back(List[i]); 779 } 780 } 781 782 bool empty() const { return Methods.empty(); } 783 784 MethodList::const_iterator methods_begin() { return Methods.begin(); } 785 MethodList::const_iterator methods_end() { return Methods.end(); } 786 }; 787 788 void PureVirtualMethodCollector::Collect(const CXXRecordDecl* RD, 789 MethodList& Methods) { 790 // First, collect the pure virtual methods for the base classes. 791 for (CXXRecordDecl::base_class_const_iterator Base = RD->bases_begin(), 792 BaseEnd = RD->bases_end(); Base != BaseEnd; ++Base) { 793 if (const RecordType *RT = Base->getType()->getAsRecordType()) { 794 const CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(RT->getDecl()); 795 if (BaseDecl && BaseDecl->isAbstract()) 796 Collect(BaseDecl, Methods); 797 } 798 } 799 800 // Next, zero out any pure virtual methods that this class overrides. 801 typedef llvm::SmallPtrSet<const CXXMethodDecl*, 4> MethodSetTy; 802 803 MethodSetTy OverriddenMethods; 804 size_t MethodsSize = Methods.size(); 805 806 for (RecordDecl::decl_iterator i = RD->decls_begin(Context), 807 e = RD->decls_end(Context); 808 i != e; ++i) { 809 // Traverse the record, looking for methods. 810 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*i)) { 811 // If the method is pre virtual, add it to the methods vector. 812 if (MD->isPure()) { 813 Methods.push_back(MD); 814 continue; 815 } 816 817 // Otherwise, record all the overridden methods in our set. 818 for (CXXMethodDecl::method_iterator I = MD->begin_overridden_methods(), 819 E = MD->end_overridden_methods(); I != E; ++I) { 820 // Keep track of the overridden methods. 821 OverriddenMethods.insert(*I); 822 } 823 } 824 } 825 826 // Now go through the methods and zero out all the ones we know are 827 // overridden. 828 for (size_t i = 0, e = MethodsSize; i != e; ++i) { 829 if (OverriddenMethods.count(Methods[i])) 830 Methods[i] = 0; 831 } 832 833 } 834} 835 836bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T, 837 unsigned DiagID, AbstractDiagSelID SelID, 838 const CXXRecordDecl *CurrentRD) { 839 840 if (!getLangOptions().CPlusPlus) 841 return false; 842 843 if (const ArrayType *AT = Context.getAsArrayType(T)) 844 return RequireNonAbstractType(Loc, AT->getElementType(), DiagID, SelID, 845 CurrentRD); 846 847 if (const PointerType *PT = T->getAsPointerType()) { 848 // Find the innermost pointer type. 849 while (const PointerType *T = PT->getPointeeType()->getAsPointerType()) 850 PT = T; 851 852 if (const ArrayType *AT = Context.getAsArrayType(PT->getPointeeType())) 853 return RequireNonAbstractType(Loc, AT->getElementType(), DiagID, SelID, 854 CurrentRD); 855 } 856 857 const RecordType *RT = T->getAsRecordType(); 858 if (!RT) 859 return false; 860 861 const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()); 862 if (!RD) 863 return false; 864 865 if (CurrentRD && CurrentRD != RD) 866 return false; 867 868 if (!RD->isAbstract()) 869 return false; 870 871 Diag(Loc, DiagID) << RD->getDeclName() << SelID; 872 873 // Check if we've already emitted the list of pure virtual functions for this 874 // class. 875 if (PureVirtualClassDiagSet && PureVirtualClassDiagSet->count(RD)) 876 return true; 877 878 PureVirtualMethodCollector Collector(Context, RD); 879 880 for (PureVirtualMethodCollector::MethodList::const_iterator I = 881 Collector.methods_begin(), E = Collector.methods_end(); I != E; ++I) { 882 const CXXMethodDecl *MD = *I; 883 884 Diag(MD->getLocation(), diag::note_pure_virtual_function) << 885 MD->getDeclName(); 886 } 887 888 if (!PureVirtualClassDiagSet) 889 PureVirtualClassDiagSet.reset(new RecordDeclSetTy); 890 PureVirtualClassDiagSet->insert(RD); 891 892 return true; 893} 894 895namespace { 896 class VISIBILITY_HIDDEN AbstractClassUsageDiagnoser 897 : public DeclVisitor<AbstractClassUsageDiagnoser, bool> { 898 Sema &SemaRef; 899 CXXRecordDecl *AbstractClass; 900 901 bool VisitDeclContext(const DeclContext *DC) { 902 bool Invalid = false; 903 904 for (CXXRecordDecl::decl_iterator I = DC->decls_begin(SemaRef.Context), 905 E = DC->decls_end(SemaRef.Context); I != E; ++I) 906 Invalid |= Visit(*I); 907 908 return Invalid; 909 } 910 911 public: 912 AbstractClassUsageDiagnoser(Sema& SemaRef, CXXRecordDecl *ac) 913 : SemaRef(SemaRef), AbstractClass(ac) { 914 Visit(SemaRef.Context.getTranslationUnitDecl()); 915 } 916 917 bool VisitFunctionDecl(const FunctionDecl *FD) { 918 if (FD->isThisDeclarationADefinition()) { 919 // No need to do the check if we're in a definition, because it requires 920 // that the return/param types are complete. 921 // because that requires 922 return VisitDeclContext(FD); 923 } 924 925 // Check the return type. 926 QualType RTy = FD->getType()->getAsFunctionType()->getResultType(); 927 bool Invalid = 928 SemaRef.RequireNonAbstractType(FD->getLocation(), RTy, 929 diag::err_abstract_type_in_decl, 930 Sema::AbstractReturnType, 931 AbstractClass); 932 933 for (FunctionDecl::param_const_iterator I = FD->param_begin(), 934 E = FD->param_end(); I != E; ++I) { 935 const ParmVarDecl *VD = *I; 936 Invalid |= 937 SemaRef.RequireNonAbstractType(VD->getLocation(), 938 VD->getOriginalType(), 939 diag::err_abstract_type_in_decl, 940 Sema::AbstractParamType, 941 AbstractClass); 942 } 943 944 return Invalid; 945 } 946 947 bool VisitDecl(const Decl* D) { 948 if (const DeclContext *DC = dyn_cast<DeclContext>(D)) 949 return VisitDeclContext(DC); 950 951 return false; 952 } 953 }; 954} 955 956void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc, 957 DeclPtrTy TagDecl, 958 SourceLocation LBrac, 959 SourceLocation RBrac) { 960 AdjustDeclIfTemplate(TagDecl); 961 ActOnFields(S, RLoc, TagDecl, 962 (DeclPtrTy*)FieldCollector->getCurFields(), 963 FieldCollector->getCurNumFields(), LBrac, RBrac, 0); 964 965 CXXRecordDecl *RD = cast<CXXRecordDecl>(TagDecl.getAs<Decl>()); 966 if (!RD->isAbstract()) { 967 // Collect all the pure virtual methods and see if this is an abstract 968 // class after all. 969 PureVirtualMethodCollector Collector(Context, RD); 970 if (!Collector.empty()) 971 RD->setAbstract(true); 972 } 973 974 if (RD->isAbstract()) 975 AbstractClassUsageDiagnoser(*this, RD); 976 977 if (RD->hasTrivialConstructor() || RD->hasTrivialDestructor()) { 978 for (RecordDecl::field_iterator i = RD->field_begin(Context), 979 e = RD->field_end(Context); i != e; ++i) { 980 // All the nonstatic data members must have trivial constructors. 981 QualType FTy = i->getType(); 982 while (const ArrayType *AT = Context.getAsArrayType(FTy)) 983 FTy = AT->getElementType(); 984 985 if (const RecordType *RT = FTy->getAsRecordType()) { 986 CXXRecordDecl *FieldRD = cast<CXXRecordDecl>(RT->getDecl()); 987 988 if (!FieldRD->hasTrivialConstructor()) 989 RD->setHasTrivialConstructor(false); 990 if (!FieldRD->hasTrivialDestructor()) 991 RD->setHasTrivialDestructor(false); 992 993 // If RD has neither a trivial constructor nor a trivial destructor 994 // we don't need to continue checking. 995 if (!RD->hasTrivialConstructor() && !RD->hasTrivialDestructor()) 996 break; 997 } 998 } 999 } 1000 1001 if (!RD->isDependentType()) 1002 AddImplicitlyDeclaredMembersToClass(RD); 1003} 1004 1005/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared 1006/// special functions, such as the default constructor, copy 1007/// constructor, or destructor, to the given C++ class (C++ 1008/// [special]p1). This routine can only be executed just before the 1009/// definition of the class is complete. 1010void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) { 1011 QualType ClassType = Context.getTypeDeclType(ClassDecl); 1012 ClassType = Context.getCanonicalType(ClassType); 1013 1014 // FIXME: Implicit declarations have exception specifications, which are 1015 // the union of the specifications of the implicitly called functions. 1016 1017 if (!ClassDecl->hasUserDeclaredConstructor()) { 1018 // C++ [class.ctor]p5: 1019 // A default constructor for a class X is a constructor of class X 1020 // that can be called without an argument. If there is no 1021 // user-declared constructor for class X, a default constructor is 1022 // implicitly declared. An implicitly-declared default constructor 1023 // is an inline public member of its class. 1024 DeclarationName Name 1025 = Context.DeclarationNames.getCXXConstructorName(ClassType); 1026 CXXConstructorDecl *DefaultCon = 1027 CXXConstructorDecl::Create(Context, ClassDecl, 1028 ClassDecl->getLocation(), Name, 1029 Context.getFunctionType(Context.VoidTy, 1030 0, 0, false, 0), 1031 /*isExplicit=*/false, 1032 /*isInline=*/true, 1033 /*isImplicitlyDeclared=*/true); 1034 DefaultCon->setAccess(AS_public); 1035 DefaultCon->setImplicit(); 1036 ClassDecl->addDecl(Context, DefaultCon); 1037 1038 // Notify the class that we've added a constructor. 1039 ClassDecl->addedConstructor(Context, DefaultCon); 1040 } 1041 1042 if (!ClassDecl->hasUserDeclaredCopyConstructor()) { 1043 // C++ [class.copy]p4: 1044 // If the class definition does not explicitly declare a copy 1045 // constructor, one is declared implicitly. 1046 1047 // C++ [class.copy]p5: 1048 // The implicitly-declared copy constructor for a class X will 1049 // have the form 1050 // 1051 // X::X(const X&) 1052 // 1053 // if 1054 bool HasConstCopyConstructor = true; 1055 1056 // -- each direct or virtual base class B of X has a copy 1057 // constructor whose first parameter is of type const B& or 1058 // const volatile B&, and 1059 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 1060 HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { 1061 const CXXRecordDecl *BaseClassDecl 1062 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 1063 HasConstCopyConstructor 1064 = BaseClassDecl->hasConstCopyConstructor(Context); 1065 } 1066 1067 // -- for all the nonstatic data members of X that are of a 1068 // class type M (or array thereof), each such class type 1069 // has a copy constructor whose first parameter is of type 1070 // const M& or const volatile M&. 1071 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(Context); 1072 HasConstCopyConstructor && Field != ClassDecl->field_end(Context); 1073 ++Field) { 1074 QualType FieldType = (*Field)->getType(); 1075 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 1076 FieldType = Array->getElementType(); 1077 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 1078 const CXXRecordDecl *FieldClassDecl 1079 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 1080 HasConstCopyConstructor 1081 = FieldClassDecl->hasConstCopyConstructor(Context); 1082 } 1083 } 1084 1085 // Otherwise, the implicitly declared copy constructor will have 1086 // the form 1087 // 1088 // X::X(X&) 1089 QualType ArgType = ClassType; 1090 if (HasConstCopyConstructor) 1091 ArgType = ArgType.withConst(); 1092 ArgType = Context.getLValueReferenceType(ArgType); 1093 1094 // An implicitly-declared copy constructor is an inline public 1095 // member of its class. 1096 DeclarationName Name 1097 = Context.DeclarationNames.getCXXConstructorName(ClassType); 1098 CXXConstructorDecl *CopyConstructor 1099 = CXXConstructorDecl::Create(Context, ClassDecl, 1100 ClassDecl->getLocation(), Name, 1101 Context.getFunctionType(Context.VoidTy, 1102 &ArgType, 1, 1103 false, 0), 1104 /*isExplicit=*/false, 1105 /*isInline=*/true, 1106 /*isImplicitlyDeclared=*/true); 1107 CopyConstructor->setAccess(AS_public); 1108 CopyConstructor->setImplicit(); 1109 1110 // Add the parameter to the constructor. 1111 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, 1112 ClassDecl->getLocation(), 1113 /*IdentifierInfo=*/0, 1114 ArgType, VarDecl::None, 0); 1115 CopyConstructor->setParams(Context, &FromParam, 1); 1116 1117 ClassDecl->addedConstructor(Context, CopyConstructor); 1118 ClassDecl->addDecl(Context, CopyConstructor); 1119 } 1120 1121 if (!ClassDecl->hasUserDeclaredCopyAssignment()) { 1122 // Note: The following rules are largely analoguous to the copy 1123 // constructor rules. Note that virtual bases are not taken into account 1124 // for determining the argument type of the operator. Note also that 1125 // operators taking an object instead of a reference are allowed. 1126 // 1127 // C++ [class.copy]p10: 1128 // If the class definition does not explicitly declare a copy 1129 // assignment operator, one is declared implicitly. 1130 // The implicitly-defined copy assignment operator for a class X 1131 // will have the form 1132 // 1133 // X& X::operator=(const X&) 1134 // 1135 // if 1136 bool HasConstCopyAssignment = true; 1137 1138 // -- each direct base class B of X has a copy assignment operator 1139 // whose parameter is of type const B&, const volatile B& or B, 1140 // and 1141 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 1142 HasConstCopyAssignment && Base != ClassDecl->bases_end(); ++Base) { 1143 const CXXRecordDecl *BaseClassDecl 1144 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 1145 HasConstCopyAssignment = BaseClassDecl->hasConstCopyAssignment(Context); 1146 } 1147 1148 // -- for all the nonstatic data members of X that are of a class 1149 // type M (or array thereof), each such class type has a copy 1150 // assignment operator whose parameter is of type const M&, 1151 // const volatile M& or M. 1152 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(Context); 1153 HasConstCopyAssignment && Field != ClassDecl->field_end(Context); 1154 ++Field) { 1155 QualType FieldType = (*Field)->getType(); 1156 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 1157 FieldType = Array->getElementType(); 1158 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 1159 const CXXRecordDecl *FieldClassDecl 1160 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 1161 HasConstCopyAssignment 1162 = FieldClassDecl->hasConstCopyAssignment(Context); 1163 } 1164 } 1165 1166 // Otherwise, the implicitly declared copy assignment operator will 1167 // have the form 1168 // 1169 // X& X::operator=(X&) 1170 QualType ArgType = ClassType; 1171 QualType RetType = Context.getLValueReferenceType(ArgType); 1172 if (HasConstCopyAssignment) 1173 ArgType = ArgType.withConst(); 1174 ArgType = Context.getLValueReferenceType(ArgType); 1175 1176 // An implicitly-declared copy assignment operator is an inline public 1177 // member of its class. 1178 DeclarationName Name = 1179 Context.DeclarationNames.getCXXOperatorName(OO_Equal); 1180 CXXMethodDecl *CopyAssignment = 1181 CXXMethodDecl::Create(Context, ClassDecl, ClassDecl->getLocation(), Name, 1182 Context.getFunctionType(RetType, &ArgType, 1, 1183 false, 0), 1184 /*isStatic=*/false, /*isInline=*/true); 1185 CopyAssignment->setAccess(AS_public); 1186 CopyAssignment->setImplicit(); 1187 1188 // Add the parameter to the operator. 1189 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyAssignment, 1190 ClassDecl->getLocation(), 1191 /*IdentifierInfo=*/0, 1192 ArgType, VarDecl::None, 0); 1193 CopyAssignment->setParams(Context, &FromParam, 1); 1194 1195 // Don't call addedAssignmentOperator. There is no way to distinguish an 1196 // implicit from an explicit assignment operator. 1197 ClassDecl->addDecl(Context, CopyAssignment); 1198 } 1199 1200 if (!ClassDecl->hasUserDeclaredDestructor()) { 1201 // C++ [class.dtor]p2: 1202 // If a class has no user-declared destructor, a destructor is 1203 // declared implicitly. An implicitly-declared destructor is an 1204 // inline public member of its class. 1205 DeclarationName Name 1206 = Context.DeclarationNames.getCXXDestructorName(ClassType); 1207 CXXDestructorDecl *Destructor 1208 = CXXDestructorDecl::Create(Context, ClassDecl, 1209 ClassDecl->getLocation(), Name, 1210 Context.getFunctionType(Context.VoidTy, 1211 0, 0, false, 0), 1212 /*isInline=*/true, 1213 /*isImplicitlyDeclared=*/true); 1214 Destructor->setAccess(AS_public); 1215 Destructor->setImplicit(); 1216 ClassDecl->addDecl(Context, Destructor); 1217 } 1218} 1219 1220void Sema::ActOnReenterTemplateScope(Scope *S, DeclPtrTy TemplateD) { 1221 TemplateDecl *Template = TemplateD.getAs<TemplateDecl>(); 1222 if (!Template) 1223 return; 1224 1225 TemplateParameterList *Params = Template->getTemplateParameters(); 1226 for (TemplateParameterList::iterator Param = Params->begin(), 1227 ParamEnd = Params->end(); 1228 Param != ParamEnd; ++Param) { 1229 NamedDecl *Named = cast<NamedDecl>(*Param); 1230 if (Named->getDeclName()) { 1231 S->AddDecl(DeclPtrTy::make(Named)); 1232 IdResolver.AddDecl(Named); 1233 } 1234 } 1235} 1236 1237/// ActOnStartDelayedCXXMethodDeclaration - We have completed 1238/// parsing a top-level (non-nested) C++ class, and we are now 1239/// parsing those parts of the given Method declaration that could 1240/// not be parsed earlier (C++ [class.mem]p2), such as default 1241/// arguments. This action should enter the scope of the given 1242/// Method declaration as if we had just parsed the qualified method 1243/// name. However, it should not bring the parameters into scope; 1244/// that will be performed by ActOnDelayedCXXMethodParameter. 1245void Sema::ActOnStartDelayedCXXMethodDeclaration(Scope *S, DeclPtrTy MethodD) { 1246 CXXScopeSpec SS; 1247 FunctionDecl *Method = cast<FunctionDecl>(MethodD.getAs<Decl>()); 1248 QualType ClassTy 1249 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 1250 SS.setScopeRep( 1251 NestedNameSpecifier::Create(Context, 0, false, ClassTy.getTypePtr())); 1252 ActOnCXXEnterDeclaratorScope(S, SS); 1253} 1254 1255/// ActOnDelayedCXXMethodParameter - We've already started a delayed 1256/// C++ method declaration. We're (re-)introducing the given 1257/// function parameter into scope for use in parsing later parts of 1258/// the method declaration. For example, we could see an 1259/// ActOnParamDefaultArgument event for this parameter. 1260void Sema::ActOnDelayedCXXMethodParameter(Scope *S, DeclPtrTy ParamD) { 1261 ParmVarDecl *Param = cast<ParmVarDecl>(ParamD.getAs<Decl>()); 1262 1263 // If this parameter has an unparsed default argument, clear it out 1264 // to make way for the parsed default argument. 1265 if (Param->hasUnparsedDefaultArg()) 1266 Param->setDefaultArg(0); 1267 1268 S->AddDecl(DeclPtrTy::make(Param)); 1269 if (Param->getDeclName()) 1270 IdResolver.AddDecl(Param); 1271} 1272 1273/// ActOnFinishDelayedCXXMethodDeclaration - We have finished 1274/// processing the delayed method declaration for Method. The method 1275/// declaration is now considered finished. There may be a separate 1276/// ActOnStartOfFunctionDef action later (not necessarily 1277/// immediately!) for this method, if it was also defined inside the 1278/// class body. 1279void Sema::ActOnFinishDelayedCXXMethodDeclaration(Scope *S, DeclPtrTy MethodD) { 1280 FunctionDecl *Method = cast<FunctionDecl>(MethodD.getAs<Decl>()); 1281 CXXScopeSpec SS; 1282 QualType ClassTy 1283 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 1284 SS.setScopeRep( 1285 NestedNameSpecifier::Create(Context, 0, false, ClassTy.getTypePtr())); 1286 ActOnCXXExitDeclaratorScope(S, SS); 1287 1288 // Now that we have our default arguments, check the constructor 1289 // again. It could produce additional diagnostics or affect whether 1290 // the class has implicitly-declared destructors, among other 1291 // things. 1292 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Method)) 1293 CheckConstructor(Constructor); 1294 1295 // Check the default arguments, which we may have added. 1296 if (!Method->isInvalidDecl()) 1297 CheckCXXDefaultArguments(Method); 1298} 1299 1300/// CheckConstructorDeclarator - Called by ActOnDeclarator to check 1301/// the well-formedness of the constructor declarator @p D with type @p 1302/// R. If there are any errors in the declarator, this routine will 1303/// emit diagnostics and set the invalid bit to true. In any case, the type 1304/// will be updated to reflect a well-formed type for the constructor and 1305/// returned. 1306QualType Sema::CheckConstructorDeclarator(Declarator &D, QualType R, 1307 FunctionDecl::StorageClass &SC) { 1308 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1309 1310 // C++ [class.ctor]p3: 1311 // A constructor shall not be virtual (10.3) or static (9.4). A 1312 // constructor can be invoked for a const, volatile or const 1313 // volatile object. A constructor shall not be declared const, 1314 // volatile, or const volatile (9.3.2). 1315 if (isVirtual) { 1316 if (!D.isInvalidType()) 1317 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be) 1318 << "virtual" << SourceRange(D.getDeclSpec().getVirtualSpecLoc()) 1319 << SourceRange(D.getIdentifierLoc()); 1320 D.setInvalidType(); 1321 } 1322 if (SC == FunctionDecl::Static) { 1323 if (!D.isInvalidType()) 1324 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be) 1325 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1326 << SourceRange(D.getIdentifierLoc()); 1327 D.setInvalidType(); 1328 SC = FunctionDecl::None; 1329 } 1330 1331 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1332 if (FTI.TypeQuals != 0) { 1333 if (FTI.TypeQuals & QualType::Const) 1334 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1335 << "const" << SourceRange(D.getIdentifierLoc()); 1336 if (FTI.TypeQuals & QualType::Volatile) 1337 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1338 << "volatile" << SourceRange(D.getIdentifierLoc()); 1339 if (FTI.TypeQuals & QualType::Restrict) 1340 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1341 << "restrict" << SourceRange(D.getIdentifierLoc()); 1342 } 1343 1344 // Rebuild the function type "R" without any type qualifiers (in 1345 // case any of the errors above fired) and with "void" as the 1346 // return type, since constructors don't have return types. We 1347 // *always* have to do this, because GetTypeForDeclarator will 1348 // put in a result type of "int" when none was specified. 1349 const FunctionProtoType *Proto = R->getAsFunctionProtoType(); 1350 return Context.getFunctionType(Context.VoidTy, Proto->arg_type_begin(), 1351 Proto->getNumArgs(), 1352 Proto->isVariadic(), 0); 1353} 1354 1355/// CheckConstructor - Checks a fully-formed constructor for 1356/// well-formedness, issuing any diagnostics required. Returns true if 1357/// the constructor declarator is invalid. 1358void Sema::CheckConstructor(CXXConstructorDecl *Constructor) { 1359 CXXRecordDecl *ClassDecl 1360 = dyn_cast<CXXRecordDecl>(Constructor->getDeclContext()); 1361 if (!ClassDecl) 1362 return Constructor->setInvalidDecl(); 1363 1364 // C++ [class.copy]p3: 1365 // A declaration of a constructor for a class X is ill-formed if 1366 // its first parameter is of type (optionally cv-qualified) X and 1367 // either there are no other parameters or else all other 1368 // parameters have default arguments. 1369 if (!Constructor->isInvalidDecl() && 1370 ((Constructor->getNumParams() == 1) || 1371 (Constructor->getNumParams() > 1 && 1372 Constructor->getParamDecl(1)->hasDefaultArg()))) { 1373 QualType ParamType = Constructor->getParamDecl(0)->getType(); 1374 QualType ClassTy = Context.getTagDeclType(ClassDecl); 1375 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { 1376 SourceLocation ParamLoc = Constructor->getParamDecl(0)->getLocation(); 1377 Diag(ParamLoc, diag::err_constructor_byvalue_arg) 1378 << CodeModificationHint::CreateInsertion(ParamLoc, " const &"); 1379 Constructor->setInvalidDecl(); 1380 } 1381 } 1382 1383 // Notify the class that we've added a constructor. 1384 ClassDecl->addedConstructor(Context, Constructor); 1385} 1386 1387static inline bool 1388FTIHasSingleVoidArgument(DeclaratorChunk::FunctionTypeInfo &FTI) { 1389 return (FTI.NumArgs == 1 && !FTI.isVariadic && FTI.ArgInfo[0].Ident == 0 && 1390 FTI.ArgInfo[0].Param && 1391 FTI.ArgInfo[0].Param.getAs<ParmVarDecl>()->getType()->isVoidType()); 1392} 1393 1394/// CheckDestructorDeclarator - Called by ActOnDeclarator to check 1395/// the well-formednes of the destructor declarator @p D with type @p 1396/// R. If there are any errors in the declarator, this routine will 1397/// emit diagnostics and set the declarator to invalid. Even if this happens, 1398/// will be updated to reflect a well-formed type for the destructor and 1399/// returned. 1400QualType Sema::CheckDestructorDeclarator(Declarator &D, 1401 FunctionDecl::StorageClass& SC) { 1402 // C++ [class.dtor]p1: 1403 // [...] A typedef-name that names a class is a class-name 1404 // (7.1.3); however, a typedef-name that names a class shall not 1405 // be used as the identifier in the declarator for a destructor 1406 // declaration. 1407 QualType DeclaratorType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1408 if (isa<TypedefType>(DeclaratorType)) { 1409 Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name) 1410 << DeclaratorType; 1411 D.setInvalidType(); 1412 } 1413 1414 // C++ [class.dtor]p2: 1415 // A destructor is used to destroy objects of its class type. A 1416 // destructor takes no parameters, and no return type can be 1417 // specified for it (not even void). The address of a destructor 1418 // shall not be taken. A destructor shall not be static. A 1419 // destructor can be invoked for a const, volatile or const 1420 // volatile object. A destructor shall not be declared const, 1421 // volatile or const volatile (9.3.2). 1422 if (SC == FunctionDecl::Static) { 1423 if (!D.isInvalidType()) 1424 Diag(D.getIdentifierLoc(), diag::err_destructor_cannot_be) 1425 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1426 << SourceRange(D.getIdentifierLoc()); 1427 SC = FunctionDecl::None; 1428 D.setInvalidType(); 1429 } 1430 if (D.getDeclSpec().hasTypeSpecifier() && !D.isInvalidType()) { 1431 // Destructors don't have return types, but the parser will 1432 // happily parse something like: 1433 // 1434 // class X { 1435 // float ~X(); 1436 // }; 1437 // 1438 // The return type will be eliminated later. 1439 Diag(D.getIdentifierLoc(), diag::err_destructor_return_type) 1440 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 1441 << SourceRange(D.getIdentifierLoc()); 1442 } 1443 1444 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1445 if (FTI.TypeQuals != 0 && !D.isInvalidType()) { 1446 if (FTI.TypeQuals & QualType::Const) 1447 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1448 << "const" << SourceRange(D.getIdentifierLoc()); 1449 if (FTI.TypeQuals & QualType::Volatile) 1450 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1451 << "volatile" << SourceRange(D.getIdentifierLoc()); 1452 if (FTI.TypeQuals & QualType::Restrict) 1453 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1454 << "restrict" << SourceRange(D.getIdentifierLoc()); 1455 D.setInvalidType(); 1456 } 1457 1458 // Make sure we don't have any parameters. 1459 if (FTI.NumArgs > 0 && !FTIHasSingleVoidArgument(FTI)) { 1460 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params); 1461 1462 // Delete the parameters. 1463 FTI.freeArgs(); 1464 D.setInvalidType(); 1465 } 1466 1467 // Make sure the destructor isn't variadic. 1468 if (FTI.isVariadic) { 1469 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic); 1470 D.setInvalidType(); 1471 } 1472 1473 // Rebuild the function type "R" without any type qualifiers or 1474 // parameters (in case any of the errors above fired) and with 1475 // "void" as the return type, since destructors don't have return 1476 // types. We *always* have to do this, because GetTypeForDeclarator 1477 // will put in a result type of "int" when none was specified. 1478 return Context.getFunctionType(Context.VoidTy, 0, 0, false, 0); 1479} 1480 1481/// CheckConversionDeclarator - Called by ActOnDeclarator to check the 1482/// well-formednes of the conversion function declarator @p D with 1483/// type @p R. If there are any errors in the declarator, this routine 1484/// will emit diagnostics and return true. Otherwise, it will return 1485/// false. Either way, the type @p R will be updated to reflect a 1486/// well-formed type for the conversion operator. 1487void Sema::CheckConversionDeclarator(Declarator &D, QualType &R, 1488 FunctionDecl::StorageClass& SC) { 1489 // C++ [class.conv.fct]p1: 1490 // Neither parameter types nor return type can be specified. The 1491 // type of a conversion function (8.3.5) is “function taking no 1492 // parameter returning conversion-type-id.” 1493 if (SC == FunctionDecl::Static) { 1494 if (!D.isInvalidType()) 1495 Diag(D.getIdentifierLoc(), diag::err_conv_function_not_member) 1496 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1497 << SourceRange(D.getIdentifierLoc()); 1498 D.setInvalidType(); 1499 SC = FunctionDecl::None; 1500 } 1501 if (D.getDeclSpec().hasTypeSpecifier() && !D.isInvalidType()) { 1502 // Conversion functions don't have return types, but the parser will 1503 // happily parse something like: 1504 // 1505 // class X { 1506 // float operator bool(); 1507 // }; 1508 // 1509 // The return type will be changed later anyway. 1510 Diag(D.getIdentifierLoc(), diag::err_conv_function_return_type) 1511 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 1512 << SourceRange(D.getIdentifierLoc()); 1513 } 1514 1515 // Make sure we don't have any parameters. 1516 if (R->getAsFunctionProtoType()->getNumArgs() > 0) { 1517 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params); 1518 1519 // Delete the parameters. 1520 D.getTypeObject(0).Fun.freeArgs(); 1521 D.setInvalidType(); 1522 } 1523 1524 // Make sure the conversion function isn't variadic. 1525 if (R->getAsFunctionProtoType()->isVariadic() && !D.isInvalidType()) { 1526 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic); 1527 D.setInvalidType(); 1528 } 1529 1530 // C++ [class.conv.fct]p4: 1531 // The conversion-type-id shall not represent a function type nor 1532 // an array type. 1533 QualType ConvType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1534 if (ConvType->isArrayType()) { 1535 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array); 1536 ConvType = Context.getPointerType(ConvType); 1537 D.setInvalidType(); 1538 } else if (ConvType->isFunctionType()) { 1539 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function); 1540 ConvType = Context.getPointerType(ConvType); 1541 D.setInvalidType(); 1542 } 1543 1544 // Rebuild the function type "R" without any parameters (in case any 1545 // of the errors above fired) and with the conversion type as the 1546 // return type. 1547 R = Context.getFunctionType(ConvType, 0, 0, false, 1548 R->getAsFunctionProtoType()->getTypeQuals()); 1549 1550 // C++0x explicit conversion operators. 1551 if (D.getDeclSpec().isExplicitSpecified() && !getLangOptions().CPlusPlus0x) 1552 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1553 diag::warn_explicit_conversion_functions) 1554 << SourceRange(D.getDeclSpec().getExplicitSpecLoc()); 1555} 1556 1557/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete 1558/// the declaration of the given C++ conversion function. This routine 1559/// is responsible for recording the conversion function in the C++ 1560/// class, if possible. 1561Sema::DeclPtrTy Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) { 1562 assert(Conversion && "Expected to receive a conversion function declaration"); 1563 1564 // Set the lexical context of this conversion function 1565 Conversion->setLexicalDeclContext(CurContext); 1566 1567 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Conversion->getDeclContext()); 1568 1569 // Make sure we aren't redeclaring the conversion function. 1570 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType()); 1571 1572 // C++ [class.conv.fct]p1: 1573 // [...] A conversion function is never used to convert a 1574 // (possibly cv-qualified) object to the (possibly cv-qualified) 1575 // same object type (or a reference to it), to a (possibly 1576 // cv-qualified) base class of that type (or a reference to it), 1577 // or to (possibly cv-qualified) void. 1578 // FIXME: Suppress this warning if the conversion function ends up being a 1579 // virtual function that overrides a virtual function in a base class. 1580 QualType ClassType 1581 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl)); 1582 if (const ReferenceType *ConvTypeRef = ConvType->getAsReferenceType()) 1583 ConvType = ConvTypeRef->getPointeeType(); 1584 if (ConvType->isRecordType()) { 1585 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType(); 1586 if (ConvType == ClassType) 1587 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used) 1588 << ClassType; 1589 else if (IsDerivedFrom(ClassType, ConvType)) 1590 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used) 1591 << ClassType << ConvType; 1592 } else if (ConvType->isVoidType()) { 1593 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used) 1594 << ClassType << ConvType; 1595 } 1596 1597 if (Conversion->getPreviousDeclaration()) { 1598 OverloadedFunctionDecl *Conversions = ClassDecl->getConversionFunctions(); 1599 for (OverloadedFunctionDecl::function_iterator 1600 Conv = Conversions->function_begin(), 1601 ConvEnd = Conversions->function_end(); 1602 Conv != ConvEnd; ++Conv) { 1603 if (*Conv == Conversion->getPreviousDeclaration()) { 1604 *Conv = Conversion; 1605 return DeclPtrTy::make(Conversion); 1606 } 1607 } 1608 assert(Conversion->isInvalidDecl() && "Conversion should not get here."); 1609 } else 1610 ClassDecl->addConversionFunction(Context, Conversion); 1611 1612 return DeclPtrTy::make(Conversion); 1613} 1614 1615//===----------------------------------------------------------------------===// 1616// Namespace Handling 1617//===----------------------------------------------------------------------===// 1618 1619/// ActOnStartNamespaceDef - This is called at the start of a namespace 1620/// definition. 1621Sema::DeclPtrTy Sema::ActOnStartNamespaceDef(Scope *NamespcScope, 1622 SourceLocation IdentLoc, 1623 IdentifierInfo *II, 1624 SourceLocation LBrace) { 1625 NamespaceDecl *Namespc = 1626 NamespaceDecl::Create(Context, CurContext, IdentLoc, II); 1627 Namespc->setLBracLoc(LBrace); 1628 1629 Scope *DeclRegionScope = NamespcScope->getParent(); 1630 1631 if (II) { 1632 // C++ [namespace.def]p2: 1633 // The identifier in an original-namespace-definition shall not have been 1634 // previously defined in the declarative region in which the 1635 // original-namespace-definition appears. The identifier in an 1636 // original-namespace-definition is the name of the namespace. Subsequently 1637 // in that declarative region, it is treated as an original-namespace-name. 1638 1639 NamedDecl *PrevDecl = LookupName(DeclRegionScope, II, LookupOrdinaryName, 1640 true); 1641 1642 if (NamespaceDecl *OrigNS = dyn_cast_or_null<NamespaceDecl>(PrevDecl)) { 1643 // This is an extended namespace definition. 1644 // Attach this namespace decl to the chain of extended namespace 1645 // definitions. 1646 OrigNS->setNextNamespace(Namespc); 1647 Namespc->setOriginalNamespace(OrigNS->getOriginalNamespace()); 1648 1649 // Remove the previous declaration from the scope. 1650 if (DeclRegionScope->isDeclScope(DeclPtrTy::make(OrigNS))) { 1651 IdResolver.RemoveDecl(OrigNS); 1652 DeclRegionScope->RemoveDecl(DeclPtrTy::make(OrigNS)); 1653 } 1654 } else if (PrevDecl) { 1655 // This is an invalid name redefinition. 1656 Diag(Namespc->getLocation(), diag::err_redefinition_different_kind) 1657 << Namespc->getDeclName(); 1658 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 1659 Namespc->setInvalidDecl(); 1660 // Continue on to push Namespc as current DeclContext and return it. 1661 } 1662 1663 PushOnScopeChains(Namespc, DeclRegionScope); 1664 } else { 1665 // FIXME: Handle anonymous namespaces 1666 } 1667 1668 // Although we could have an invalid decl (i.e. the namespace name is a 1669 // redefinition), push it as current DeclContext and try to continue parsing. 1670 // FIXME: We should be able to push Namespc here, so that the each DeclContext 1671 // for the namespace has the declarations that showed up in that particular 1672 // namespace definition. 1673 PushDeclContext(NamespcScope, Namespc); 1674 return DeclPtrTy::make(Namespc); 1675} 1676 1677/// ActOnFinishNamespaceDef - This callback is called after a namespace is 1678/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. 1679void Sema::ActOnFinishNamespaceDef(DeclPtrTy D, SourceLocation RBrace) { 1680 Decl *Dcl = D.getAs<Decl>(); 1681 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); 1682 assert(Namespc && "Invalid parameter, expected NamespaceDecl"); 1683 Namespc->setRBracLoc(RBrace); 1684 PopDeclContext(); 1685} 1686 1687Sema::DeclPtrTy Sema::ActOnUsingDirective(Scope *S, 1688 SourceLocation UsingLoc, 1689 SourceLocation NamespcLoc, 1690 const CXXScopeSpec &SS, 1691 SourceLocation IdentLoc, 1692 IdentifierInfo *NamespcName, 1693 AttributeList *AttrList) { 1694 assert(!SS.isInvalid() && "Invalid CXXScopeSpec."); 1695 assert(NamespcName && "Invalid NamespcName."); 1696 assert(IdentLoc.isValid() && "Invalid NamespceName location."); 1697 assert(S->getFlags() & Scope::DeclScope && "Invalid Scope."); 1698 1699 UsingDirectiveDecl *UDir = 0; 1700 1701 // Lookup namespace name. 1702 LookupResult R = LookupParsedName(S, &SS, NamespcName, 1703 LookupNamespaceName, false); 1704 if (R.isAmbiguous()) { 1705 DiagnoseAmbiguousLookup(R, NamespcName, IdentLoc); 1706 return DeclPtrTy(); 1707 } 1708 if (NamedDecl *NS = R) { 1709 assert(isa<NamespaceDecl>(NS) && "expected namespace decl"); 1710 // C++ [namespace.udir]p1: 1711 // A using-directive specifies that the names in the nominated 1712 // namespace can be used in the scope in which the 1713 // using-directive appears after the using-directive. During 1714 // unqualified name lookup (3.4.1), the names appear as if they 1715 // were declared in the nearest enclosing namespace which 1716 // contains both the using-directive and the nominated 1717 // namespace. [Note: in this context, “contains” means “contains 1718 // directly or indirectly”. ] 1719 1720 // Find enclosing context containing both using-directive and 1721 // nominated namespace. 1722 DeclContext *CommonAncestor = cast<DeclContext>(NS); 1723 while (CommonAncestor && !CommonAncestor->Encloses(CurContext)) 1724 CommonAncestor = CommonAncestor->getParent(); 1725 1726 UDir = UsingDirectiveDecl::Create(Context, 1727 CurContext, UsingLoc, 1728 NamespcLoc, 1729 SS.getRange(), 1730 (NestedNameSpecifier *)SS.getScopeRep(), 1731 IdentLoc, 1732 cast<NamespaceDecl>(NS), 1733 CommonAncestor); 1734 PushUsingDirective(S, UDir); 1735 } else { 1736 Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange(); 1737 } 1738 1739 // FIXME: We ignore attributes for now. 1740 delete AttrList; 1741 return DeclPtrTy::make(UDir); 1742} 1743 1744void Sema::PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir) { 1745 // If scope has associated entity, then using directive is at namespace 1746 // or translation unit scope. We add UsingDirectiveDecls, into 1747 // it's lookup structure. 1748 if (DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity())) 1749 Ctx->addDecl(Context, UDir); 1750 else 1751 // Otherwise it is block-sope. using-directives will affect lookup 1752 // only to the end of scope. 1753 S->PushUsingDirective(DeclPtrTy::make(UDir)); 1754} 1755 1756/// getNamespaceDecl - Returns the namespace a decl represents. If the decl 1757/// is a namespace alias, returns the namespace it points to. 1758static inline NamespaceDecl *getNamespaceDecl(NamedDecl *D) { 1759 if (NamespaceAliasDecl *AD = dyn_cast_or_null<NamespaceAliasDecl>(D)) 1760 return AD->getNamespace(); 1761 return dyn_cast_or_null<NamespaceDecl>(D); 1762} 1763 1764Sema::DeclPtrTy Sema::ActOnNamespaceAliasDef(Scope *S, 1765 SourceLocation NamespaceLoc, 1766 SourceLocation AliasLoc, 1767 IdentifierInfo *Alias, 1768 const CXXScopeSpec &SS, 1769 SourceLocation IdentLoc, 1770 IdentifierInfo *Ident) { 1771 1772 // Lookup the namespace name. 1773 LookupResult R = LookupParsedName(S, &SS, Ident, LookupNamespaceName, false); 1774 1775 // Check if we have a previous declaration with the same name. 1776 if (NamedDecl *PrevDecl = LookupName(S, Alias, LookupOrdinaryName, true)) { 1777 if (NamespaceAliasDecl *AD = dyn_cast<NamespaceAliasDecl>(PrevDecl)) { 1778 // We already have an alias with the same name that points to the same 1779 // namespace, so don't create a new one. 1780 if (!R.isAmbiguous() && AD->getNamespace() == getNamespaceDecl(R)) 1781 return DeclPtrTy(); 1782 } 1783 1784 unsigned DiagID = isa<NamespaceDecl>(PrevDecl) ? diag::err_redefinition : 1785 diag::err_redefinition_different_kind; 1786 Diag(AliasLoc, DiagID) << Alias; 1787 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 1788 return DeclPtrTy(); 1789 } 1790 1791 if (R.isAmbiguous()) { 1792 DiagnoseAmbiguousLookup(R, Ident, IdentLoc); 1793 return DeclPtrTy(); 1794 } 1795 1796 if (!R) { 1797 Diag(NamespaceLoc, diag::err_expected_namespace_name) << SS.getRange(); 1798 return DeclPtrTy(); 1799 } 1800 1801 NamespaceAliasDecl *AliasDecl = 1802 NamespaceAliasDecl::Create(Context, CurContext, NamespaceLoc, AliasLoc, 1803 Alias, SS.getRange(), 1804 (NestedNameSpecifier *)SS.getScopeRep(), 1805 IdentLoc, R); 1806 1807 CurContext->addDecl(Context, AliasDecl); 1808 return DeclPtrTy::make(AliasDecl); 1809} 1810 1811void Sema::InitializeVarWithConstructor(VarDecl *VD, 1812 CXXConstructorDecl *Constructor, 1813 QualType DeclInitType, 1814 Expr **Exprs, unsigned NumExprs) { 1815 Expr *Temp = CXXConstructExpr::Create(Context, DeclInitType, Constructor, 1816 false, Exprs, NumExprs); 1817 VD->setInit(Context, Temp); 1818} 1819 1820/// AddCXXDirectInitializerToDecl - This action is called immediately after 1821/// ActOnDeclarator, when a C++ direct initializer is present. 1822/// e.g: "int x(1);" 1823void Sema::AddCXXDirectInitializerToDecl(DeclPtrTy Dcl, 1824 SourceLocation LParenLoc, 1825 MultiExprArg Exprs, 1826 SourceLocation *CommaLocs, 1827 SourceLocation RParenLoc) { 1828 unsigned NumExprs = Exprs.size(); 1829 assert(NumExprs != 0 && Exprs.get() && "missing expressions"); 1830 Decl *RealDecl = Dcl.getAs<Decl>(); 1831 1832 // If there is no declaration, there was an error parsing it. Just ignore 1833 // the initializer. 1834 if (RealDecl == 0) 1835 return; 1836 1837 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1838 if (!VDecl) { 1839 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 1840 RealDecl->setInvalidDecl(); 1841 return; 1842 } 1843 1844 // FIXME: Need to handle dependent types and expressions here. 1845 1846 // We will treat direct-initialization as a copy-initialization: 1847 // int x(1); -as-> int x = 1; 1848 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); 1849 // 1850 // Clients that want to distinguish between the two forms, can check for 1851 // direct initializer using VarDecl::hasCXXDirectInitializer(). 1852 // A major benefit is that clients that don't particularly care about which 1853 // exactly form was it (like the CodeGen) can handle both cases without 1854 // special case code. 1855 1856 // C++ 8.5p11: 1857 // The form of initialization (using parentheses or '=') is generally 1858 // insignificant, but does matter when the entity being initialized has a 1859 // class type. 1860 QualType DeclInitType = VDecl->getType(); 1861 if (const ArrayType *Array = Context.getAsArrayType(DeclInitType)) 1862 DeclInitType = Array->getElementType(); 1863 1864 // FIXME: This isn't the right place to complete the type. 1865 if (RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 1866 diag::err_typecheck_decl_incomplete_type)) { 1867 VDecl->setInvalidDecl(); 1868 return; 1869 } 1870 1871 if (VDecl->getType()->isRecordType()) { 1872 CXXConstructorDecl *Constructor 1873 = PerformInitializationByConstructor(DeclInitType, 1874 (Expr **)Exprs.get(), NumExprs, 1875 VDecl->getLocation(), 1876 SourceRange(VDecl->getLocation(), 1877 RParenLoc), 1878 VDecl->getDeclName(), 1879 IK_Direct); 1880 if (!Constructor) 1881 RealDecl->setInvalidDecl(); 1882 else { 1883 VDecl->setCXXDirectInitializer(true); 1884 InitializeVarWithConstructor(VDecl, Constructor, DeclInitType, 1885 (Expr**)Exprs.release(), NumExprs); 1886 } 1887 return; 1888 } 1889 1890 if (NumExprs > 1) { 1891 Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg) 1892 << SourceRange(VDecl->getLocation(), RParenLoc); 1893 RealDecl->setInvalidDecl(); 1894 return; 1895 } 1896 1897 // Let clients know that initialization was done with a direct initializer. 1898 VDecl->setCXXDirectInitializer(true); 1899 1900 assert(NumExprs == 1 && "Expected 1 expression"); 1901 // Set the init expression, handles conversions. 1902 AddInitializerToDecl(Dcl, ExprArg(*this, Exprs.release()[0]), 1903 /*DirectInit=*/true); 1904} 1905 1906/// PerformInitializationByConstructor - Perform initialization by 1907/// constructor (C++ [dcl.init]p14), which may occur as part of 1908/// direct-initialization or copy-initialization. We are initializing 1909/// an object of type @p ClassType with the given arguments @p 1910/// Args. @p Loc is the location in the source code where the 1911/// initializer occurs (e.g., a declaration, member initializer, 1912/// functional cast, etc.) while @p Range covers the whole 1913/// initialization. @p InitEntity is the entity being initialized, 1914/// which may by the name of a declaration or a type. @p Kind is the 1915/// kind of initialization we're performing, which affects whether 1916/// explicit constructors will be considered. When successful, returns 1917/// the constructor that will be used to perform the initialization; 1918/// when the initialization fails, emits a diagnostic and returns 1919/// null. 1920CXXConstructorDecl * 1921Sema::PerformInitializationByConstructor(QualType ClassType, 1922 Expr **Args, unsigned NumArgs, 1923 SourceLocation Loc, SourceRange Range, 1924 DeclarationName InitEntity, 1925 InitializationKind Kind) { 1926 const RecordType *ClassRec = ClassType->getAsRecordType(); 1927 assert(ClassRec && "Can only initialize a class type here"); 1928 1929 // C++ [dcl.init]p14: 1930 // 1931 // If the initialization is direct-initialization, or if it is 1932 // copy-initialization where the cv-unqualified version of the 1933 // source type is the same class as, or a derived class of, the 1934 // class of the destination, constructors are considered. The 1935 // applicable constructors are enumerated (13.3.1.3), and the 1936 // best one is chosen through overload resolution (13.3). The 1937 // constructor so selected is called to initialize the object, 1938 // with the initializer expression(s) as its argument(s). If no 1939 // constructor applies, or the overload resolution is ambiguous, 1940 // the initialization is ill-formed. 1941 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1942 OverloadCandidateSet CandidateSet; 1943 1944 // Add constructors to the overload set. 1945 DeclarationName ConstructorName 1946 = Context.DeclarationNames.getCXXConstructorName( 1947 Context.getCanonicalType(ClassType.getUnqualifiedType())); 1948 DeclContext::lookup_const_iterator Con, ConEnd; 1949 for (llvm::tie(Con, ConEnd) = ClassDecl->lookup(Context, ConstructorName); 1950 Con != ConEnd; ++Con) { 1951 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 1952 if ((Kind == IK_Direct) || 1953 (Kind == IK_Copy && Constructor->isConvertingConstructor()) || 1954 (Kind == IK_Default && Constructor->isDefaultConstructor())) 1955 AddOverloadCandidate(Constructor, Args, NumArgs, CandidateSet); 1956 } 1957 1958 // FIXME: When we decide not to synthesize the implicitly-declared 1959 // constructors, we'll need to make them appear here. 1960 1961 OverloadCandidateSet::iterator Best; 1962 switch (BestViableFunction(CandidateSet, Best)) { 1963 case OR_Success: 1964 // We found a constructor. Return it. 1965 return cast<CXXConstructorDecl>(Best->Function); 1966 1967 case OR_No_Viable_Function: 1968 if (InitEntity) 1969 Diag(Loc, diag::err_ovl_no_viable_function_in_init) 1970 << InitEntity << Range; 1971 else 1972 Diag(Loc, diag::err_ovl_no_viable_function_in_init) 1973 << ClassType << Range; 1974 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1975 return 0; 1976 1977 case OR_Ambiguous: 1978 if (InitEntity) 1979 Diag(Loc, diag::err_ovl_ambiguous_init) << InitEntity << Range; 1980 else 1981 Diag(Loc, diag::err_ovl_ambiguous_init) << ClassType << Range; 1982 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1983 return 0; 1984 1985 case OR_Deleted: 1986 if (InitEntity) 1987 Diag(Loc, diag::err_ovl_deleted_init) 1988 << Best->Function->isDeleted() 1989 << InitEntity << Range; 1990 else 1991 Diag(Loc, diag::err_ovl_deleted_init) 1992 << Best->Function->isDeleted() 1993 << InitEntity << Range; 1994 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1995 return 0; 1996 } 1997 1998 return 0; 1999} 2000 2001/// CompareReferenceRelationship - Compare the two types T1 and T2 to 2002/// determine whether they are reference-related, 2003/// reference-compatible, reference-compatible with added 2004/// qualification, or incompatible, for use in C++ initialization by 2005/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 2006/// type, and the first type (T1) is the pointee type of the reference 2007/// type being initialized. 2008Sema::ReferenceCompareResult 2009Sema::CompareReferenceRelationship(QualType T1, QualType T2, 2010 bool& DerivedToBase) { 2011 assert(!T1->isReferenceType() && 2012 "T1 must be the pointee type of the reference type"); 2013 assert(!T2->isReferenceType() && "T2 cannot be a reference type"); 2014 2015 T1 = Context.getCanonicalType(T1); 2016 T2 = Context.getCanonicalType(T2); 2017 QualType UnqualT1 = T1.getUnqualifiedType(); 2018 QualType UnqualT2 = T2.getUnqualifiedType(); 2019 2020 // C++ [dcl.init.ref]p4: 2021 // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is 2022 // reference-related to “cv2 T2” if T1 is the same type as T2, or 2023 // T1 is a base class of T2. 2024 if (UnqualT1 == UnqualT2) 2025 DerivedToBase = false; 2026 else if (IsDerivedFrom(UnqualT2, UnqualT1)) 2027 DerivedToBase = true; 2028 else 2029 return Ref_Incompatible; 2030 2031 // At this point, we know that T1 and T2 are reference-related (at 2032 // least). 2033 2034 // C++ [dcl.init.ref]p4: 2035 // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is 2036 // reference-related to T2 and cv1 is the same cv-qualification 2037 // as, or greater cv-qualification than, cv2. For purposes of 2038 // overload resolution, cases for which cv1 is greater 2039 // cv-qualification than cv2 are identified as 2040 // reference-compatible with added qualification (see 13.3.3.2). 2041 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 2042 return Ref_Compatible; 2043 else if (T1.isMoreQualifiedThan(T2)) 2044 return Ref_Compatible_With_Added_Qualification; 2045 else 2046 return Ref_Related; 2047} 2048 2049/// CheckReferenceInit - Check the initialization of a reference 2050/// variable with the given initializer (C++ [dcl.init.ref]). Init is 2051/// the initializer (either a simple initializer or an initializer 2052/// list), and DeclType is the type of the declaration. When ICS is 2053/// non-null, this routine will compute the implicit conversion 2054/// sequence according to C++ [over.ics.ref] and will not produce any 2055/// diagnostics; when ICS is null, it will emit diagnostics when any 2056/// errors are found. Either way, a return value of true indicates 2057/// that there was a failure, a return value of false indicates that 2058/// the reference initialization succeeded. 2059/// 2060/// When @p SuppressUserConversions, user-defined conversions are 2061/// suppressed. 2062/// When @p AllowExplicit, we also permit explicit user-defined 2063/// conversion functions. 2064/// When @p ForceRValue, we unconditionally treat the initializer as an rvalue. 2065bool 2066Sema::CheckReferenceInit(Expr *&Init, QualType DeclType, 2067 ImplicitConversionSequence *ICS, 2068 bool SuppressUserConversions, 2069 bool AllowExplicit, bool ForceRValue) { 2070 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 2071 2072 QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); 2073 QualType T2 = Init->getType(); 2074 2075 // If the initializer is the address of an overloaded function, try 2076 // to resolve the overloaded function. If all goes well, T2 is the 2077 // type of the resulting function. 2078 if (Context.getCanonicalType(T2) == Context.OverloadTy) { 2079 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Init, DeclType, 2080 ICS != 0); 2081 if (Fn) { 2082 // Since we're performing this reference-initialization for 2083 // real, update the initializer with the resulting function. 2084 if (!ICS) { 2085 if (DiagnoseUseOfDecl(Fn, Init->getSourceRange().getBegin())) 2086 return true; 2087 2088 FixOverloadedFunctionReference(Init, Fn); 2089 } 2090 2091 T2 = Fn->getType(); 2092 } 2093 } 2094 2095 // Compute some basic properties of the types and the initializer. 2096 bool isRValRef = DeclType->isRValueReferenceType(); 2097 bool DerivedToBase = false; 2098 Expr::isLvalueResult InitLvalue = ForceRValue ? Expr::LV_InvalidExpression : 2099 Init->isLvalue(Context); 2100 ReferenceCompareResult RefRelationship 2101 = CompareReferenceRelationship(T1, T2, DerivedToBase); 2102 2103 // Most paths end in a failed conversion. 2104 if (ICS) 2105 ICS->ConversionKind = ImplicitConversionSequence::BadConversion; 2106 2107 // C++ [dcl.init.ref]p5: 2108 // A reference to type “cv1 T1” is initialized by an expression 2109 // of type “cv2 T2” as follows: 2110 2111 // -- If the initializer expression 2112 2113 // Rvalue references cannot bind to lvalues (N2812). 2114 // There is absolutely no situation where they can. In particular, note that 2115 // this is ill-formed, even if B has a user-defined conversion to A&&: 2116 // B b; 2117 // A&& r = b; 2118 if (isRValRef && InitLvalue == Expr::LV_Valid) { 2119 if (!ICS) 2120 Diag(Init->getSourceRange().getBegin(), diag::err_lvalue_to_rvalue_ref) 2121 << Init->getSourceRange(); 2122 return true; 2123 } 2124 2125 bool BindsDirectly = false; 2126 // -- is an lvalue (but is not a bit-field), and “cv1 T1” is 2127 // reference-compatible with “cv2 T2,” or 2128 // 2129 // Note that the bit-field check is skipped if we are just computing 2130 // the implicit conversion sequence (C++ [over.best.ics]p2). 2131 if (InitLvalue == Expr::LV_Valid && (ICS || !Init->getBitField()) && 2132 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 2133 BindsDirectly = true; 2134 2135 if (ICS) { 2136 // C++ [over.ics.ref]p1: 2137 // When a parameter of reference type binds directly (8.5.3) 2138 // to an argument expression, the implicit conversion sequence 2139 // is the identity conversion, unless the argument expression 2140 // has a type that is a derived class of the parameter type, 2141 // in which case the implicit conversion sequence is a 2142 // derived-to-base Conversion (13.3.3.1). 2143 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 2144 ICS->Standard.First = ICK_Identity; 2145 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 2146 ICS->Standard.Third = ICK_Identity; 2147 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 2148 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 2149 ICS->Standard.ReferenceBinding = true; 2150 ICS->Standard.DirectBinding = true; 2151 ICS->Standard.RRefBinding = false; 2152 ICS->Standard.CopyConstructor = 0; 2153 2154 // Nothing more to do: the inaccessibility/ambiguity check for 2155 // derived-to-base conversions is suppressed when we're 2156 // computing the implicit conversion sequence (C++ 2157 // [over.best.ics]p2). 2158 return false; 2159 } else { 2160 // Perform the conversion. 2161 // FIXME: Binding to a subobject of the lvalue is going to require more 2162 // AST annotation than this. 2163 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 2164 } 2165 } 2166 2167 // -- has a class type (i.e., T2 is a class type) and can be 2168 // implicitly converted to an lvalue of type “cv3 T3,” 2169 // where “cv1 T1” is reference-compatible with “cv3 T3” 2170 // 92) (this conversion is selected by enumerating the 2171 // applicable conversion functions (13.3.1.6) and choosing 2172 // the best one through overload resolution (13.3)), 2173 if (!isRValRef && !SuppressUserConversions && T2->isRecordType()) { 2174 // FIXME: Look for conversions in base classes! 2175 CXXRecordDecl *T2RecordDecl 2176 = dyn_cast<CXXRecordDecl>(T2->getAsRecordType()->getDecl()); 2177 2178 OverloadCandidateSet CandidateSet; 2179 OverloadedFunctionDecl *Conversions 2180 = T2RecordDecl->getConversionFunctions(); 2181 for (OverloadedFunctionDecl::function_iterator Func 2182 = Conversions->function_begin(); 2183 Func != Conversions->function_end(); ++Func) { 2184 CXXConversionDecl *Conv = cast<CXXConversionDecl>(*Func); 2185 2186 // If the conversion function doesn't return a reference type, 2187 // it can't be considered for this conversion. 2188 if (Conv->getConversionType()->isLValueReferenceType() && 2189 (AllowExplicit || !Conv->isExplicit())) 2190 AddConversionCandidate(Conv, Init, DeclType, CandidateSet); 2191 } 2192 2193 OverloadCandidateSet::iterator Best; 2194 switch (BestViableFunction(CandidateSet, Best)) { 2195 case OR_Success: 2196 // This is a direct binding. 2197 BindsDirectly = true; 2198 2199 if (ICS) { 2200 // C++ [over.ics.ref]p1: 2201 // 2202 // [...] If the parameter binds directly to the result of 2203 // applying a conversion function to the argument 2204 // expression, the implicit conversion sequence is a 2205 // user-defined conversion sequence (13.3.3.1.2), with the 2206 // second standard conversion sequence either an identity 2207 // conversion or, if the conversion function returns an 2208 // entity of a type that is a derived class of the parameter 2209 // type, a derived-to-base Conversion. 2210 ICS->ConversionKind = ImplicitConversionSequence::UserDefinedConversion; 2211 ICS->UserDefined.Before = Best->Conversions[0].Standard; 2212 ICS->UserDefined.After = Best->FinalConversion; 2213 ICS->UserDefined.ConversionFunction = Best->Function; 2214 assert(ICS->UserDefined.After.ReferenceBinding && 2215 ICS->UserDefined.After.DirectBinding && 2216 "Expected a direct reference binding!"); 2217 return false; 2218 } else { 2219 // Perform the conversion. 2220 // FIXME: Binding to a subobject of the lvalue is going to require more 2221 // AST annotation than this. 2222 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 2223 } 2224 break; 2225 2226 case OR_Ambiguous: 2227 assert(false && "Ambiguous reference binding conversions not implemented."); 2228 return true; 2229 2230 case OR_No_Viable_Function: 2231 case OR_Deleted: 2232 // There was no suitable conversion, or we found a deleted 2233 // conversion; continue with other checks. 2234 break; 2235 } 2236 } 2237 2238 if (BindsDirectly) { 2239 // C++ [dcl.init.ref]p4: 2240 // [...] In all cases where the reference-related or 2241 // reference-compatible relationship of two types is used to 2242 // establish the validity of a reference binding, and T1 is a 2243 // base class of T2, a program that necessitates such a binding 2244 // is ill-formed if T1 is an inaccessible (clause 11) or 2245 // ambiguous (10.2) base class of T2. 2246 // 2247 // Note that we only check this condition when we're allowed to 2248 // complain about errors, because we should not be checking for 2249 // ambiguity (or inaccessibility) unless the reference binding 2250 // actually happens. 2251 if (DerivedToBase) 2252 return CheckDerivedToBaseConversion(T2, T1, 2253 Init->getSourceRange().getBegin(), 2254 Init->getSourceRange()); 2255 else 2256 return false; 2257 } 2258 2259 // -- Otherwise, the reference shall be to a non-volatile const 2260 // type (i.e., cv1 shall be const), or the reference shall be an 2261 // rvalue reference and the initializer expression shall be an rvalue. 2262 if (!isRValRef && T1.getCVRQualifiers() != QualType::Const) { 2263 if (!ICS) 2264 Diag(Init->getSourceRange().getBegin(), 2265 diag::err_not_reference_to_const_init) 2266 << T1 << (InitLvalue != Expr::LV_Valid? "temporary" : "value") 2267 << T2 << Init->getSourceRange(); 2268 return true; 2269 } 2270 2271 // -- If the initializer expression is an rvalue, with T2 a 2272 // class type, and “cv1 T1” is reference-compatible with 2273 // “cv2 T2,” the reference is bound in one of the 2274 // following ways (the choice is implementation-defined): 2275 // 2276 // -- The reference is bound to the object represented by 2277 // the rvalue (see 3.10) or to a sub-object within that 2278 // object. 2279 // 2280 // -- A temporary of type “cv1 T2” [sic] is created, and 2281 // a constructor is called to copy the entire rvalue 2282 // object into the temporary. The reference is bound to 2283 // the temporary or to a sub-object within the 2284 // temporary. 2285 // 2286 // The constructor that would be used to make the copy 2287 // shall be callable whether or not the copy is actually 2288 // done. 2289 // 2290 // Note that C++0x [dcl.init.ref]p5 takes away this implementation 2291 // freedom, so we will always take the first option and never build 2292 // a temporary in this case. FIXME: We will, however, have to check 2293 // for the presence of a copy constructor in C++98/03 mode. 2294 if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && 2295 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 2296 if (ICS) { 2297 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 2298 ICS->Standard.First = ICK_Identity; 2299 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 2300 ICS->Standard.Third = ICK_Identity; 2301 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 2302 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 2303 ICS->Standard.ReferenceBinding = true; 2304 ICS->Standard.DirectBinding = false; 2305 ICS->Standard.RRefBinding = isRValRef; 2306 ICS->Standard.CopyConstructor = 0; 2307 } else { 2308 // FIXME: Binding to a subobject of the rvalue is going to require more 2309 // AST annotation than this. 2310 ImpCastExprToType(Init, T1, /*isLvalue=*/false); 2311 } 2312 return false; 2313 } 2314 2315 // -- Otherwise, a temporary of type “cv1 T1” is created and 2316 // initialized from the initializer expression using the 2317 // rules for a non-reference copy initialization (8.5). The 2318 // reference is then bound to the temporary. If T1 is 2319 // reference-related to T2, cv1 must be the same 2320 // cv-qualification as, or greater cv-qualification than, 2321 // cv2; otherwise, the program is ill-formed. 2322 if (RefRelationship == Ref_Related) { 2323 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 2324 // we would be reference-compatible or reference-compatible with 2325 // added qualification. But that wasn't the case, so the reference 2326 // initialization fails. 2327 if (!ICS) 2328 Diag(Init->getSourceRange().getBegin(), 2329 diag::err_reference_init_drops_quals) 2330 << T1 << (InitLvalue != Expr::LV_Valid? "temporary" : "value") 2331 << T2 << Init->getSourceRange(); 2332 return true; 2333 } 2334 2335 // If at least one of the types is a class type, the types are not 2336 // related, and we aren't allowed any user conversions, the 2337 // reference binding fails. This case is important for breaking 2338 // recursion, since TryImplicitConversion below will attempt to 2339 // create a temporary through the use of a copy constructor. 2340 if (SuppressUserConversions && RefRelationship == Ref_Incompatible && 2341 (T1->isRecordType() || T2->isRecordType())) { 2342 if (!ICS) 2343 Diag(Init->getSourceRange().getBegin(), 2344 diag::err_typecheck_convert_incompatible) 2345 << DeclType << Init->getType() << "initializing" << Init->getSourceRange(); 2346 return true; 2347 } 2348 2349 // Actually try to convert the initializer to T1. 2350 if (ICS) { 2351 // C++ [over.ics.ref]p2: 2352 // 2353 // When a parameter of reference type is not bound directly to 2354 // an argument expression, the conversion sequence is the one 2355 // required to convert the argument expression to the 2356 // underlying type of the reference according to 2357 // 13.3.3.1. Conceptually, this conversion sequence corresponds 2358 // to copy-initializing a temporary of the underlying type with 2359 // the argument expression. Any difference in top-level 2360 // cv-qualification is subsumed by the initialization itself 2361 // and does not constitute a conversion. 2362 *ICS = TryImplicitConversion(Init, T1, SuppressUserConversions); 2363 // Of course, that's still a reference binding. 2364 if (ICS->ConversionKind == ImplicitConversionSequence::StandardConversion) { 2365 ICS->Standard.ReferenceBinding = true; 2366 ICS->Standard.RRefBinding = isRValRef; 2367 } else if(ICS->ConversionKind == 2368 ImplicitConversionSequence::UserDefinedConversion) { 2369 ICS->UserDefined.After.ReferenceBinding = true; 2370 ICS->UserDefined.After.RRefBinding = isRValRef; 2371 } 2372 return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; 2373 } else { 2374 return PerformImplicitConversion(Init, T1, "initializing"); 2375 } 2376} 2377 2378/// CheckOverloadedOperatorDeclaration - Check whether the declaration 2379/// of this overloaded operator is well-formed. If so, returns false; 2380/// otherwise, emits appropriate diagnostics and returns true. 2381bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) { 2382 assert(FnDecl && FnDecl->isOverloadedOperator() && 2383 "Expected an overloaded operator declaration"); 2384 2385 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator(); 2386 2387 // C++ [over.oper]p5: 2388 // The allocation and deallocation functions, operator new, 2389 // operator new[], operator delete and operator delete[], are 2390 // described completely in 3.7.3. The attributes and restrictions 2391 // found in the rest of this subclause do not apply to them unless 2392 // explicitly stated in 3.7.3. 2393 // FIXME: Write a separate routine for checking this. For now, just allow it. 2394 if (Op == OO_New || Op == OO_Array_New || 2395 Op == OO_Delete || Op == OO_Array_Delete) 2396 return false; 2397 2398 // C++ [over.oper]p6: 2399 // An operator function shall either be a non-static member 2400 // function or be a non-member function and have at least one 2401 // parameter whose type is a class, a reference to a class, an 2402 // enumeration, or a reference to an enumeration. 2403 if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl)) { 2404 if (MethodDecl->isStatic()) 2405 return Diag(FnDecl->getLocation(), 2406 diag::err_operator_overload_static) << FnDecl->getDeclName(); 2407 } else { 2408 bool ClassOrEnumParam = false; 2409 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(), 2410 ParamEnd = FnDecl->param_end(); 2411 Param != ParamEnd; ++Param) { 2412 QualType ParamType = (*Param)->getType().getNonReferenceType(); 2413 if (ParamType->isRecordType() || ParamType->isEnumeralType()) { 2414 ClassOrEnumParam = true; 2415 break; 2416 } 2417 } 2418 2419 if (!ClassOrEnumParam) 2420 return Diag(FnDecl->getLocation(), 2421 diag::err_operator_overload_needs_class_or_enum) 2422 << FnDecl->getDeclName(); 2423 } 2424 2425 // C++ [over.oper]p8: 2426 // An operator function cannot have default arguments (8.3.6), 2427 // except where explicitly stated below. 2428 // 2429 // Only the function-call operator allows default arguments 2430 // (C++ [over.call]p1). 2431 if (Op != OO_Call) { 2432 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 2433 Param != FnDecl->param_end(); ++Param) { 2434 if ((*Param)->hasUnparsedDefaultArg()) 2435 return Diag((*Param)->getLocation(), 2436 diag::err_operator_overload_default_arg) 2437 << FnDecl->getDeclName(); 2438 else if (Expr *DefArg = (*Param)->getDefaultArg()) 2439 return Diag((*Param)->getLocation(), 2440 diag::err_operator_overload_default_arg) 2441 << FnDecl->getDeclName() << DefArg->getSourceRange(); 2442 } 2443 } 2444 2445 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = { 2446 { false, false, false } 2447#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \ 2448 , { Unary, Binary, MemberOnly } 2449#include "clang/Basic/OperatorKinds.def" 2450 }; 2451 2452 bool CanBeUnaryOperator = OperatorUses[Op][0]; 2453 bool CanBeBinaryOperator = OperatorUses[Op][1]; 2454 bool MustBeMemberOperator = OperatorUses[Op][2]; 2455 2456 // C++ [over.oper]p8: 2457 // [...] Operator functions cannot have more or fewer parameters 2458 // than the number required for the corresponding operator, as 2459 // described in the rest of this subclause. 2460 unsigned NumParams = FnDecl->getNumParams() 2461 + (isa<CXXMethodDecl>(FnDecl)? 1 : 0); 2462 if (Op != OO_Call && 2463 ((NumParams == 1 && !CanBeUnaryOperator) || 2464 (NumParams == 2 && !CanBeBinaryOperator) || 2465 (NumParams < 1) || (NumParams > 2))) { 2466 // We have the wrong number of parameters. 2467 unsigned ErrorKind; 2468 if (CanBeUnaryOperator && CanBeBinaryOperator) { 2469 ErrorKind = 2; // 2 -> unary or binary. 2470 } else if (CanBeUnaryOperator) { 2471 ErrorKind = 0; // 0 -> unary 2472 } else { 2473 assert(CanBeBinaryOperator && 2474 "All non-call overloaded operators are unary or binary!"); 2475 ErrorKind = 1; // 1 -> binary 2476 } 2477 2478 return Diag(FnDecl->getLocation(), diag::err_operator_overload_must_be) 2479 << FnDecl->getDeclName() << NumParams << ErrorKind; 2480 } 2481 2482 // Overloaded operators other than operator() cannot be variadic. 2483 if (Op != OO_Call && 2484 FnDecl->getType()->getAsFunctionProtoType()->isVariadic()) { 2485 return Diag(FnDecl->getLocation(), diag::err_operator_overload_variadic) 2486 << FnDecl->getDeclName(); 2487 } 2488 2489 // Some operators must be non-static member functions. 2490 if (MustBeMemberOperator && !isa<CXXMethodDecl>(FnDecl)) { 2491 return Diag(FnDecl->getLocation(), 2492 diag::err_operator_overload_must_be_member) 2493 << FnDecl->getDeclName(); 2494 } 2495 2496 // C++ [over.inc]p1: 2497 // The user-defined function called operator++ implements the 2498 // prefix and postfix ++ operator. If this function is a member 2499 // function with no parameters, or a non-member function with one 2500 // parameter of class or enumeration type, it defines the prefix 2501 // increment operator ++ for objects of that type. If the function 2502 // is a member function with one parameter (which shall be of type 2503 // int) or a non-member function with two parameters (the second 2504 // of which shall be of type int), it defines the postfix 2505 // increment operator ++ for objects of that type. 2506 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) { 2507 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1); 2508 bool ParamIsInt = false; 2509 if (const BuiltinType *BT = LastParam->getType()->getAsBuiltinType()) 2510 ParamIsInt = BT->getKind() == BuiltinType::Int; 2511 2512 if (!ParamIsInt) 2513 return Diag(LastParam->getLocation(), 2514 diag::err_operator_overload_post_incdec_must_be_int) 2515 << LastParam->getType() << (Op == OO_MinusMinus); 2516 } 2517 2518 // Notify the class if it got an assignment operator. 2519 if (Op == OO_Equal) { 2520 // Would have returned earlier otherwise. 2521 assert(isa<CXXMethodDecl>(FnDecl) && 2522 "Overloaded = not member, but not filtered."); 2523 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 2524 Method->getParent()->addedAssignmentOperator(Context, Method); 2525 } 2526 2527 return false; 2528} 2529 2530/// ActOnStartLinkageSpecification - Parsed the beginning of a C++ 2531/// linkage specification, including the language and (if present) 2532/// the '{'. ExternLoc is the location of the 'extern', LangLoc is 2533/// the location of the language string literal, which is provided 2534/// by Lang/StrSize. LBraceLoc, if valid, provides the location of 2535/// the '{' brace. Otherwise, this linkage specification does not 2536/// have any braces. 2537Sema::DeclPtrTy Sema::ActOnStartLinkageSpecification(Scope *S, 2538 SourceLocation ExternLoc, 2539 SourceLocation LangLoc, 2540 const char *Lang, 2541 unsigned StrSize, 2542 SourceLocation LBraceLoc) { 2543 LinkageSpecDecl::LanguageIDs Language; 2544 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2545 Language = LinkageSpecDecl::lang_c; 2546 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2547 Language = LinkageSpecDecl::lang_cxx; 2548 else { 2549 Diag(LangLoc, diag::err_bad_language); 2550 return DeclPtrTy(); 2551 } 2552 2553 // FIXME: Add all the various semantics of linkage specifications 2554 2555 LinkageSpecDecl *D = LinkageSpecDecl::Create(Context, CurContext, 2556 LangLoc, Language, 2557 LBraceLoc.isValid()); 2558 CurContext->addDecl(Context, D); 2559 PushDeclContext(S, D); 2560 return DeclPtrTy::make(D); 2561} 2562 2563/// ActOnFinishLinkageSpecification - Completely the definition of 2564/// the C++ linkage specification LinkageSpec. If RBraceLoc is 2565/// valid, it's the position of the closing '}' brace in a linkage 2566/// specification that uses braces. 2567Sema::DeclPtrTy Sema::ActOnFinishLinkageSpecification(Scope *S, 2568 DeclPtrTy LinkageSpec, 2569 SourceLocation RBraceLoc) { 2570 if (LinkageSpec) 2571 PopDeclContext(); 2572 return LinkageSpec; 2573} 2574 2575/// \brief Perform semantic analysis for the variable declaration that 2576/// occurs within a C++ catch clause, returning the newly-created 2577/// variable. 2578VarDecl *Sema::BuildExceptionDeclaration(Scope *S, QualType ExDeclType, 2579 IdentifierInfo *Name, 2580 SourceLocation Loc, 2581 SourceRange Range) { 2582 bool Invalid = false; 2583 2584 // Arrays and functions decay. 2585 if (ExDeclType->isArrayType()) 2586 ExDeclType = Context.getArrayDecayedType(ExDeclType); 2587 else if (ExDeclType->isFunctionType()) 2588 ExDeclType = Context.getPointerType(ExDeclType); 2589 2590 // C++ 15.3p1: The exception-declaration shall not denote an incomplete type. 2591 // The exception-declaration shall not denote a pointer or reference to an 2592 // incomplete type, other than [cv] void*. 2593 // N2844 forbids rvalue references. 2594 if(!ExDeclType->isDependentType() && ExDeclType->isRValueReferenceType()) { 2595 Diag(Loc, diag::err_catch_rvalue_ref) << Range; 2596 Invalid = true; 2597 } 2598 2599 QualType BaseType = ExDeclType; 2600 int Mode = 0; // 0 for direct type, 1 for pointer, 2 for reference 2601 unsigned DK = diag::err_catch_incomplete; 2602 if (const PointerType *Ptr = BaseType->getAsPointerType()) { 2603 BaseType = Ptr->getPointeeType(); 2604 Mode = 1; 2605 DK = diag::err_catch_incomplete_ptr; 2606 } else if(const ReferenceType *Ref = BaseType->getAsReferenceType()) { 2607 // For the purpose of error recovery, we treat rvalue refs like lvalue refs. 2608 BaseType = Ref->getPointeeType(); 2609 Mode = 2; 2610 DK = diag::err_catch_incomplete_ref; 2611 } 2612 if (!Invalid && (Mode == 0 || !BaseType->isVoidType()) && 2613 !BaseType->isDependentType() && RequireCompleteType(Loc, BaseType, DK)) 2614 Invalid = true; 2615 2616 if (!Invalid && !ExDeclType->isDependentType() && 2617 RequireNonAbstractType(Loc, ExDeclType, 2618 diag::err_abstract_type_in_decl, 2619 AbstractVariableType)) 2620 Invalid = true; 2621 2622 // FIXME: Need to test for ability to copy-construct and destroy the 2623 // exception variable. 2624 2625 // FIXME: Need to check for abstract classes. 2626 2627 VarDecl *ExDecl = VarDecl::Create(Context, CurContext, Loc, 2628 Name, ExDeclType, VarDecl::None, 2629 Range.getBegin()); 2630 2631 if (Invalid) 2632 ExDecl->setInvalidDecl(); 2633 2634 return ExDecl; 2635} 2636 2637/// ActOnExceptionDeclarator - Parsed the exception-declarator in a C++ catch 2638/// handler. 2639Sema::DeclPtrTy Sema::ActOnExceptionDeclarator(Scope *S, Declarator &D) { 2640 QualType ExDeclType = GetTypeForDeclarator(D, S); 2641 2642 bool Invalid = D.isInvalidType(); 2643 IdentifierInfo *II = D.getIdentifier(); 2644 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2645 // The scope should be freshly made just for us. There is just no way 2646 // it contains any previous declaration. 2647 assert(!S->isDeclScope(DeclPtrTy::make(PrevDecl))); 2648 if (PrevDecl->isTemplateParameter()) { 2649 // Maybe we will complain about the shadowed template parameter. 2650 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2651 } 2652 } 2653 2654 if (D.getCXXScopeSpec().isSet() && !Invalid) { 2655 Diag(D.getIdentifierLoc(), diag::err_qualified_catch_declarator) 2656 << D.getCXXScopeSpec().getRange(); 2657 Invalid = true; 2658 } 2659 2660 VarDecl *ExDecl = BuildExceptionDeclaration(S, ExDeclType, 2661 D.getIdentifier(), 2662 D.getIdentifierLoc(), 2663 D.getDeclSpec().getSourceRange()); 2664 2665 if (Invalid) 2666 ExDecl->setInvalidDecl(); 2667 2668 // Add the exception declaration into this scope. 2669 if (II) 2670 PushOnScopeChains(ExDecl, S); 2671 else 2672 CurContext->addDecl(Context, ExDecl); 2673 2674 ProcessDeclAttributes(S, ExDecl, D); 2675 return DeclPtrTy::make(ExDecl); 2676} 2677 2678Sema::DeclPtrTy Sema::ActOnStaticAssertDeclaration(SourceLocation AssertLoc, 2679 ExprArg assertexpr, 2680 ExprArg assertmessageexpr) { 2681 Expr *AssertExpr = (Expr *)assertexpr.get(); 2682 StringLiteral *AssertMessage = 2683 cast<StringLiteral>((Expr *)assertmessageexpr.get()); 2684 2685 if (!AssertExpr->isTypeDependent() && !AssertExpr->isValueDependent()) { 2686 llvm::APSInt Value(32); 2687 if (!AssertExpr->isIntegerConstantExpr(Value, Context)) { 2688 Diag(AssertLoc, diag::err_static_assert_expression_is_not_constant) << 2689 AssertExpr->getSourceRange(); 2690 return DeclPtrTy(); 2691 } 2692 2693 if (Value == 0) { 2694 std::string str(AssertMessage->getStrData(), 2695 AssertMessage->getByteLength()); 2696 Diag(AssertLoc, diag::err_static_assert_failed) 2697 << str << AssertExpr->getSourceRange(); 2698 } 2699 } 2700 2701 assertexpr.release(); 2702 assertmessageexpr.release(); 2703 Decl *Decl = StaticAssertDecl::Create(Context, CurContext, AssertLoc, 2704 AssertExpr, AssertMessage); 2705 2706 CurContext->addDecl(Context, Decl); 2707 return DeclPtrTy::make(Decl); 2708} 2709 2710bool Sema::ActOnFriendDecl(Scope *S, SourceLocation FriendLoc, DeclPtrTy Dcl) { 2711 if (!(S->getFlags() & Scope::ClassScope)) { 2712 Diag(FriendLoc, diag::err_friend_decl_outside_class); 2713 return true; 2714 } 2715 2716 return false; 2717} 2718 2719void Sema::SetDeclDeleted(DeclPtrTy dcl, SourceLocation DelLoc) { 2720 Decl *Dcl = dcl.getAs<Decl>(); 2721 FunctionDecl *Fn = dyn_cast<FunctionDecl>(Dcl); 2722 if (!Fn) { 2723 Diag(DelLoc, diag::err_deleted_non_function); 2724 return; 2725 } 2726 if (const FunctionDecl *Prev = Fn->getPreviousDeclaration()) { 2727 Diag(DelLoc, diag::err_deleted_decl_not_first); 2728 Diag(Prev->getLocation(), diag::note_previous_declaration); 2729 // If the declaration wasn't the first, we delete the function anyway for 2730 // recovery. 2731 } 2732 Fn->setDeleted(); 2733} 2734 2735static void SearchForReturnInStmt(Sema &Self, Stmt *S) { 2736 for (Stmt::child_iterator CI = S->child_begin(), E = S->child_end(); CI != E; 2737 ++CI) { 2738 Stmt *SubStmt = *CI; 2739 if (!SubStmt) 2740 continue; 2741 if (isa<ReturnStmt>(SubStmt)) 2742 Self.Diag(SubStmt->getSourceRange().getBegin(), 2743 diag::err_return_in_constructor_handler); 2744 if (!isa<Expr>(SubStmt)) 2745 SearchForReturnInStmt(Self, SubStmt); 2746 } 2747} 2748 2749void Sema::DiagnoseReturnInConstructorExceptionHandler(CXXTryStmt *TryBlock) { 2750 for (unsigned I = 0, E = TryBlock->getNumHandlers(); I != E; ++I) { 2751 CXXCatchStmt *Handler = TryBlock->getHandler(I); 2752 SearchForReturnInStmt(*this, Handler); 2753 } 2754} 2755 2756bool Sema::CheckOverridingFunctionReturnType(const CXXMethodDecl *New, 2757 const CXXMethodDecl *Old) { 2758 QualType NewTy = New->getType()->getAsFunctionType()->getResultType(); 2759 QualType OldTy = Old->getType()->getAsFunctionType()->getResultType(); 2760 2761 QualType CNewTy = Context.getCanonicalType(NewTy); 2762 QualType COldTy = Context.getCanonicalType(OldTy); 2763 2764 if (CNewTy == COldTy && 2765 CNewTy.getCVRQualifiers() == COldTy.getCVRQualifiers()) 2766 return false; 2767 2768 // Check if the return types are covariant 2769 QualType NewClassTy, OldClassTy; 2770 2771 /// Both types must be pointers or references to classes. 2772 if (PointerType *NewPT = dyn_cast<PointerType>(NewTy)) { 2773 if (PointerType *OldPT = dyn_cast<PointerType>(OldTy)) { 2774 NewClassTy = NewPT->getPointeeType(); 2775 OldClassTy = OldPT->getPointeeType(); 2776 } 2777 } else if (ReferenceType *NewRT = dyn_cast<ReferenceType>(NewTy)) { 2778 if (ReferenceType *OldRT = dyn_cast<ReferenceType>(OldTy)) { 2779 NewClassTy = NewRT->getPointeeType(); 2780 OldClassTy = OldRT->getPointeeType(); 2781 } 2782 } 2783 2784 // The return types aren't either both pointers or references to a class type. 2785 if (NewClassTy.isNull()) { 2786 Diag(New->getLocation(), 2787 diag::err_different_return_type_for_overriding_virtual_function) 2788 << New->getDeclName() << NewTy << OldTy; 2789 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2790 2791 return true; 2792 } 2793 2794 if (NewClassTy.getUnqualifiedType() != OldClassTy.getUnqualifiedType()) { 2795 // Check if the new class derives from the old class. 2796 if (!IsDerivedFrom(NewClassTy, OldClassTy)) { 2797 Diag(New->getLocation(), 2798 diag::err_covariant_return_not_derived) 2799 << New->getDeclName() << NewTy << OldTy; 2800 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2801 return true; 2802 } 2803 2804 // Check if we the conversion from derived to base is valid. 2805 if (CheckDerivedToBaseConversion(NewClassTy, OldClassTy, 2806 diag::err_covariant_return_inaccessible_base, 2807 diag::err_covariant_return_ambiguous_derived_to_base_conv, 2808 // FIXME: Should this point to the return type? 2809 New->getLocation(), SourceRange(), New->getDeclName())) { 2810 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2811 return true; 2812 } 2813 } 2814 2815 // The qualifiers of the return types must be the same. 2816 if (CNewTy.getCVRQualifiers() != COldTy.getCVRQualifiers()) { 2817 Diag(New->getLocation(), 2818 diag::err_covariant_return_type_different_qualifications) 2819 << New->getDeclName() << NewTy << OldTy; 2820 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2821 return true; 2822 }; 2823 2824 2825 // The new class type must have the same or less qualifiers as the old type. 2826 if (NewClassTy.isMoreQualifiedThan(OldClassTy)) { 2827 Diag(New->getLocation(), 2828 diag::err_covariant_return_type_class_type_more_qualified) 2829 << New->getDeclName() << NewTy << OldTy; 2830 Diag(Old->getLocation(), diag::note_overridden_virtual_function); 2831 return true; 2832 }; 2833 2834 return false; 2835} 2836