SemaDeclCXX.cpp revision 8d7ba402ba062994e242c97719685d6d66a056dd
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(DeclTy *param, SourceLocation EqualLoc, 109 ExprArg defarg) { 110 ParmVarDecl *Param = (ParmVarDecl *)param; 111 ExprOwningPtr<Expr> DefaultArg(this, (Expr *)defarg.release()); 112 QualType ParamType = Param->getType(); 113 114 // Default arguments are only permitted in C++ 115 if (!getLangOptions().CPlusPlus) { 116 Diag(EqualLoc, diag::err_param_default_argument) 117 << DefaultArg->getSourceRange(); 118 Param->setInvalidDecl(); 119 return; 120 } 121 122 // C++ [dcl.fct.default]p5 123 // A default argument expression is implicitly converted (clause 124 // 4) to the parameter type. The default argument expression has 125 // the same semantic constraints as the initializer expression in 126 // a declaration of a variable of the parameter type, using the 127 // copy-initialization semantics (8.5). 128 Expr *DefaultArgPtr = DefaultArg.get(); 129 bool DefaultInitFailed = CheckInitializerTypes(DefaultArgPtr, ParamType, 130 EqualLoc, 131 Param->getDeclName(), 132 /*DirectInit=*/false); 133 if (DefaultArgPtr != DefaultArg.get()) { 134 DefaultArg.take(); 135 DefaultArg.reset(DefaultArgPtr); 136 } 137 if (DefaultInitFailed) { 138 return; 139 } 140 141 // Check that the default argument is well-formed 142 CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg.get(), this); 143 if (DefaultArgChecker.Visit(DefaultArg.get())) { 144 Param->setInvalidDecl(); 145 return; 146 } 147 148 // Okay: add the default argument to the parameter 149 Param->setDefaultArg(DefaultArg.take()); 150} 151 152/// ActOnParamUnparsedDefaultArgument - We've seen a default 153/// argument for a function parameter, but we can't parse it yet 154/// because we're inside a class definition. Note that this default 155/// argument will be parsed later. 156void Sema::ActOnParamUnparsedDefaultArgument(DeclTy *param, 157 SourceLocation EqualLoc) { 158 ParmVarDecl *Param = (ParmVarDecl*)param; 159 if (Param) 160 Param->setUnparsedDefaultArg(); 161} 162 163/// ActOnParamDefaultArgumentError - Parsing or semantic analysis of 164/// the default argument for the parameter param failed. 165void Sema::ActOnParamDefaultArgumentError(DeclTy *param) { 166 ((ParmVarDecl*)param)->setInvalidDecl(); 167} 168 169/// CheckExtraCXXDefaultArguments - Check for any extra default 170/// arguments in the declarator, which is not a function declaration 171/// or definition and therefore is not permitted to have default 172/// arguments. This routine should be invoked for every declarator 173/// that is not a function declaration or definition. 174void Sema::CheckExtraCXXDefaultArguments(Declarator &D) { 175 // C++ [dcl.fct.default]p3 176 // A default argument expression shall be specified only in the 177 // parameter-declaration-clause of a function declaration or in a 178 // template-parameter (14.1). It shall not be specified for a 179 // parameter pack. If it is specified in a 180 // parameter-declaration-clause, it shall not occur within a 181 // declarator or abstract-declarator of a parameter-declaration. 182 for (unsigned i = 0; i < D.getNumTypeObjects(); ++i) { 183 DeclaratorChunk &chunk = D.getTypeObject(i); 184 if (chunk.Kind == DeclaratorChunk::Function) { 185 for (unsigned argIdx = 0; argIdx < chunk.Fun.NumArgs; ++argIdx) { 186 ParmVarDecl *Param = (ParmVarDecl *)chunk.Fun.ArgInfo[argIdx].Param; 187 if (Param->hasUnparsedDefaultArg()) { 188 CachedTokens *Toks = chunk.Fun.ArgInfo[argIdx].DefaultArgTokens; 189 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc) 190 << SourceRange((*Toks)[1].getLocation(), Toks->back().getLocation()); 191 delete Toks; 192 chunk.Fun.ArgInfo[argIdx].DefaultArgTokens = 0; 193 } else if (Param->getDefaultArg()) { 194 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc) 195 << Param->getDefaultArg()->getSourceRange(); 196 Param->setDefaultArg(0); 197 } 198 } 199 } 200 } 201} 202 203// MergeCXXFunctionDecl - Merge two declarations of the same C++ 204// function, once we already know that they have the same 205// type. Subroutine of MergeFunctionDecl. Returns true if there was an 206// error, false otherwise. 207bool Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old) { 208 bool Invalid = false; 209 210 // C++ [dcl.fct.default]p4: 211 // 212 // For non-template functions, default arguments can be added in 213 // later declarations of a function in the same 214 // scope. Declarations in different scopes have completely 215 // distinct sets of default arguments. That is, declarations in 216 // inner scopes do not acquire default arguments from 217 // declarations in outer scopes, and vice versa. In a given 218 // function declaration, all parameters subsequent to a 219 // parameter with a default argument shall have default 220 // arguments supplied in this or previous declarations. A 221 // default argument shall not be redefined by a later 222 // declaration (not even to the same value). 223 for (unsigned p = 0, NumParams = Old->getNumParams(); p < NumParams; ++p) { 224 ParmVarDecl *OldParam = Old->getParamDecl(p); 225 ParmVarDecl *NewParam = New->getParamDecl(p); 226 227 if(OldParam->getDefaultArg() && NewParam->getDefaultArg()) { 228 Diag(NewParam->getLocation(), 229 diag::err_param_default_argument_redefinition) 230 << NewParam->getDefaultArg()->getSourceRange(); 231 Diag(OldParam->getLocation(), diag::note_previous_definition); 232 Invalid = true; 233 } else if (OldParam->getDefaultArg()) { 234 // Merge the old default argument into the new parameter 235 NewParam->setDefaultArg(OldParam->getDefaultArg()); 236 } 237 } 238 239 return Invalid; 240} 241 242/// CheckCXXDefaultArguments - Verify that the default arguments for a 243/// function declaration are well-formed according to C++ 244/// [dcl.fct.default]. 245void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) { 246 unsigned NumParams = FD->getNumParams(); 247 unsigned p; 248 249 // Find first parameter with a default argument 250 for (p = 0; p < NumParams; ++p) { 251 ParmVarDecl *Param = FD->getParamDecl(p); 252 if (Param->getDefaultArg()) 253 break; 254 } 255 256 // C++ [dcl.fct.default]p4: 257 // In a given function declaration, all parameters 258 // subsequent to a parameter with a default argument shall 259 // have default arguments supplied in this or previous 260 // declarations. A default argument shall not be redefined 261 // by a later declaration (not even to the same value). 262 unsigned LastMissingDefaultArg = 0; 263 for(; p < NumParams; ++p) { 264 ParmVarDecl *Param = FD->getParamDecl(p); 265 if (!Param->getDefaultArg()) { 266 if (Param->isInvalidDecl()) 267 /* We already complained about this parameter. */; 268 else if (Param->getIdentifier()) 269 Diag(Param->getLocation(), 270 diag::err_param_default_argument_missing_name) 271 << Param->getIdentifier(); 272 else 273 Diag(Param->getLocation(), 274 diag::err_param_default_argument_missing); 275 276 LastMissingDefaultArg = p; 277 } 278 } 279 280 if (LastMissingDefaultArg > 0) { 281 // Some default arguments were missing. Clear out all of the 282 // default arguments up to (and including) the last missing 283 // default argument, so that we leave the function parameters 284 // in a semantically valid state. 285 for (p = 0; p <= LastMissingDefaultArg; ++p) { 286 ParmVarDecl *Param = FD->getParamDecl(p); 287 if (Param->getDefaultArg()) { 288 if (!Param->hasUnparsedDefaultArg()) 289 Param->getDefaultArg()->Destroy(Context); 290 Param->setDefaultArg(0); 291 } 292 } 293 } 294} 295 296/// isCurrentClassName - Determine whether the identifier II is the 297/// name of the class type currently being defined. In the case of 298/// nested classes, this will only return true if II is the name of 299/// the innermost class. 300bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *, 301 const CXXScopeSpec *SS) { 302 CXXRecordDecl *CurDecl; 303 if (SS && SS->isSet() && !SS->isInvalid()) { 304 DeclContext *DC = computeDeclContext(*SS); 305 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC); 306 } else 307 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 308 309 if (CurDecl) 310 return &II == CurDecl->getIdentifier(); 311 else 312 return false; 313} 314 315/// \brief Check the validity of a C++ base class specifier. 316/// 317/// \returns a new CXXBaseSpecifier if well-formed, emits diagnostics 318/// and returns NULL otherwise. 319CXXBaseSpecifier * 320Sema::CheckBaseSpecifier(CXXRecordDecl *Class, 321 SourceRange SpecifierRange, 322 bool Virtual, AccessSpecifier Access, 323 QualType BaseType, 324 SourceLocation BaseLoc) { 325 // C++ [class.union]p1: 326 // A union shall not have base classes. 327 if (Class->isUnion()) { 328 Diag(Class->getLocation(), diag::err_base_clause_on_union) 329 << SpecifierRange; 330 return 0; 331 } 332 333 if (BaseType->isDependentType()) 334 return new CXXBaseSpecifier(SpecifierRange, Virtual, 335 Class->getTagKind() == RecordDecl::TK_class, 336 Access, BaseType); 337 338 // Base specifiers must be record types. 339 if (!BaseType->isRecordType()) { 340 Diag(BaseLoc, diag::err_base_must_be_class) << SpecifierRange; 341 return 0; 342 } 343 344 // C++ [class.union]p1: 345 // A union shall not be used as a base class. 346 if (BaseType->isUnionType()) { 347 Diag(BaseLoc, diag::err_union_as_base_class) << SpecifierRange; 348 return 0; 349 } 350 351 // C++ [class.derived]p2: 352 // The class-name in a base-specifier shall not be an incompletely 353 // defined class. 354 if (RequireCompleteType(BaseLoc, BaseType, diag::err_incomplete_base_class, 355 SpecifierRange)) 356 return 0; 357 358 // If the base class is polymorphic, the new one is, too. 359 RecordDecl *BaseDecl = BaseType->getAsRecordType()->getDecl(); 360 assert(BaseDecl && "Record type has no declaration"); 361 BaseDecl = BaseDecl->getDefinition(Context); 362 assert(BaseDecl && "Base type is not incomplete, but has no definition"); 363 if (cast<CXXRecordDecl>(BaseDecl)->isPolymorphic()) 364 Class->setPolymorphic(true); 365 366 // C++ [dcl.init.aggr]p1: 367 // An aggregate is [...] a class with [...] no base classes [...]. 368 Class->setAggregate(false); 369 Class->setPOD(false); 370 371 // Create the base specifier. 372 // FIXME: Allocate via ASTContext? 373 return new CXXBaseSpecifier(SpecifierRange, Virtual, 374 Class->getTagKind() == RecordDecl::TK_class, 375 Access, BaseType); 376} 377 378/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is 379/// one entry in the base class list of a class specifier, for 380/// example: 381/// class foo : public bar, virtual private baz { 382/// 'public bar' and 'virtual private baz' are each base-specifiers. 383Sema::BaseResult 384Sema::ActOnBaseSpecifier(DeclTy *classdecl, SourceRange SpecifierRange, 385 bool Virtual, AccessSpecifier Access, 386 TypeTy *basetype, SourceLocation BaseLoc) { 387 AdjustDeclIfTemplate(classdecl); 388 CXXRecordDecl *Class = cast<CXXRecordDecl>((Decl*)classdecl); 389 QualType BaseType = QualType::getFromOpaquePtr(basetype); 390 if (CXXBaseSpecifier *BaseSpec = CheckBaseSpecifier(Class, SpecifierRange, 391 Virtual, Access, 392 BaseType, BaseLoc)) 393 return BaseSpec; 394 395 return true; 396} 397 398/// \brief Performs the actual work of attaching the given base class 399/// specifiers to a C++ class. 400bool Sema::AttachBaseSpecifiers(CXXRecordDecl *Class, CXXBaseSpecifier **Bases, 401 unsigned NumBases) { 402 if (NumBases == 0) 403 return false; 404 405 // Used to keep track of which base types we have already seen, so 406 // that we can properly diagnose redundant direct base types. Note 407 // that the key is always the unqualified canonical type of the base 408 // class. 409 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes; 410 411 // Copy non-redundant base specifiers into permanent storage. 412 unsigned NumGoodBases = 0; 413 bool Invalid = false; 414 for (unsigned idx = 0; idx < NumBases; ++idx) { 415 QualType NewBaseType 416 = Context.getCanonicalType(Bases[idx]->getType()); 417 NewBaseType = NewBaseType.getUnqualifiedType(); 418 419 if (KnownBaseTypes[NewBaseType]) { 420 // C++ [class.mi]p3: 421 // A class shall not be specified as a direct base class of a 422 // derived class more than once. 423 Diag(Bases[idx]->getSourceRange().getBegin(), 424 diag::err_duplicate_base_class) 425 << KnownBaseTypes[NewBaseType]->getType() 426 << Bases[idx]->getSourceRange(); 427 428 // Delete the duplicate base class specifier; we're going to 429 // overwrite its pointer later. 430 delete Bases[idx]; 431 432 Invalid = true; 433 } else { 434 // Okay, add this new base class. 435 KnownBaseTypes[NewBaseType] = Bases[idx]; 436 Bases[NumGoodBases++] = Bases[idx]; 437 } 438 } 439 440 // Attach the remaining base class specifiers to the derived class. 441 Class->setBases(Bases, NumGoodBases); 442 443 // Delete the remaining (good) base class specifiers, since their 444 // data has been copied into the CXXRecordDecl. 445 for (unsigned idx = 0; idx < NumGoodBases; ++idx) 446 delete Bases[idx]; 447 448 return Invalid; 449} 450 451/// ActOnBaseSpecifiers - Attach the given base specifiers to the 452/// class, after checking whether there are any duplicate base 453/// classes. 454void Sema::ActOnBaseSpecifiers(DeclTy *ClassDecl, BaseTy **Bases, 455 unsigned NumBases) { 456 if (!ClassDecl || !Bases || !NumBases) 457 return; 458 459 AdjustDeclIfTemplate(ClassDecl); 460 AttachBaseSpecifiers(cast<CXXRecordDecl>((Decl*)ClassDecl), 461 (CXXBaseSpecifier**)(Bases), NumBases); 462} 463 464//===----------------------------------------------------------------------===// 465// C++ class member Handling 466//===----------------------------------------------------------------------===// 467 468/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member 469/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the 470/// bitfield width if there is one and 'InitExpr' specifies the initializer if 471/// any. 'LastInGroup' is non-null for cases where one declspec has multiple 472/// declarators on it. 473Sema::DeclTy * 474Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D, 475 ExprTy *BW, ExprTy *InitExpr, 476 DeclTy *LastInGroup) { 477 const DeclSpec &DS = D.getDeclSpec(); 478 DeclarationName Name = GetNameForDeclarator(D); 479 Expr *BitWidth = static_cast<Expr*>(BW); 480 Expr *Init = static_cast<Expr*>(InitExpr); 481 SourceLocation Loc = D.getIdentifierLoc(); 482 483 bool isFunc = D.isFunctionDeclarator(); 484 485 // C++ 9.2p6: A member shall not be declared to have automatic storage 486 // duration (auto, register) or with the extern storage-class-specifier. 487 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class 488 // data members and cannot be applied to names declared const or static, 489 // and cannot be applied to reference members. 490 switch (DS.getStorageClassSpec()) { 491 case DeclSpec::SCS_unspecified: 492 case DeclSpec::SCS_typedef: 493 case DeclSpec::SCS_static: 494 // FALL THROUGH. 495 break; 496 case DeclSpec::SCS_mutable: 497 if (isFunc) { 498 if (DS.getStorageClassSpecLoc().isValid()) 499 Diag(DS.getStorageClassSpecLoc(), diag::err_mutable_function); 500 else 501 Diag(DS.getThreadSpecLoc(), diag::err_mutable_function); 502 503 // FIXME: It would be nicer if the keyword was ignored only for this 504 // declarator. Otherwise we could get follow-up errors. 505 D.getMutableDeclSpec().ClearStorageClassSpecs(); 506 } else { 507 QualType T = GetTypeForDeclarator(D, S); 508 diag::kind err = static_cast<diag::kind>(0); 509 if (T->isReferenceType()) 510 err = diag::err_mutable_reference; 511 else if (T.isConstQualified()) 512 err = diag::err_mutable_const; 513 if (err != 0) { 514 if (DS.getStorageClassSpecLoc().isValid()) 515 Diag(DS.getStorageClassSpecLoc(), err); 516 else 517 Diag(DS.getThreadSpecLoc(), err); 518 // FIXME: It would be nicer if the keyword was ignored only for this 519 // declarator. Otherwise we could get follow-up errors. 520 D.getMutableDeclSpec().ClearStorageClassSpecs(); 521 } 522 } 523 break; 524 default: 525 if (DS.getStorageClassSpecLoc().isValid()) 526 Diag(DS.getStorageClassSpecLoc(), 527 diag::err_storageclass_invalid_for_member); 528 else 529 Diag(DS.getThreadSpecLoc(), diag::err_storageclass_invalid_for_member); 530 D.getMutableDeclSpec().ClearStorageClassSpecs(); 531 } 532 533 if (!isFunc && 534 D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_typename && 535 D.getNumTypeObjects() == 0) { 536 // Check also for this case: 537 // 538 // typedef int f(); 539 // f a; 540 // 541 QualType TDType = QualType::getFromOpaquePtr(DS.getTypeRep()); 542 isFunc = TDType->isFunctionType(); 543 } 544 545 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified || 546 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) && 547 !isFunc); 548 549 Decl *Member; 550 if (isInstField) { 551 Member = HandleField(S, cast<CXXRecordDecl>(CurContext), Loc, D, BitWidth, 552 AS); 553 assert(Member && "HandleField never returns null"); 554 } else { 555 Member = static_cast<Decl*>(ActOnDeclarator(S, D, LastInGroup)); 556 if (!Member) { 557 if (BitWidth) DeleteExpr(BitWidth); 558 return LastInGroup; 559 } 560 561 // Non-instance-fields can't have a bitfield. 562 if (BitWidth) { 563 if (Member->isInvalidDecl()) { 564 // don't emit another diagnostic. 565 } else if (isa<VarDecl>(Member)) { 566 // C++ 9.6p3: A bit-field shall not be a static member. 567 // "static member 'A' cannot be a bit-field" 568 Diag(Loc, diag::err_static_not_bitfield) 569 << Name << BitWidth->getSourceRange(); 570 } else if (isa<TypedefDecl>(Member)) { 571 // "typedef member 'x' cannot be a bit-field" 572 Diag(Loc, diag::err_typedef_not_bitfield) 573 << Name << BitWidth->getSourceRange(); 574 } else { 575 // A function typedef ("typedef int f(); f a;"). 576 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 577 Diag(Loc, diag::err_not_integral_type_bitfield) 578 << Name << cast<ValueDecl>(Member)->getType() 579 << BitWidth->getSourceRange(); 580 } 581 582 DeleteExpr(BitWidth); 583 BitWidth = 0; 584 Member->setInvalidDecl(); 585 } 586 587 Member->setAccess(AS); 588 } 589 590 assert((Name || isInstField) && "No identifier for non-field ?"); 591 592 if (Init) 593 AddInitializerToDecl(Member, ExprArg(*this, Init), false); 594 595 if (isInstField) { 596 FieldCollector->Add(cast<FieldDecl>(Member)); 597 return LastInGroup; 598 } 599 return Member; 600} 601 602/// ActOnMemInitializer - Handle a C++ member initializer. 603Sema::MemInitResult 604Sema::ActOnMemInitializer(DeclTy *ConstructorD, 605 Scope *S, 606 IdentifierInfo *MemberOrBase, 607 SourceLocation IdLoc, 608 SourceLocation LParenLoc, 609 ExprTy **Args, unsigned NumArgs, 610 SourceLocation *CommaLocs, 611 SourceLocation RParenLoc) { 612 CXXConstructorDecl *Constructor 613 = dyn_cast<CXXConstructorDecl>((Decl*)ConstructorD); 614 if (!Constructor) { 615 // The user wrote a constructor initializer on a function that is 616 // not a C++ constructor. Ignore the error for now, because we may 617 // have more member initializers coming; we'll diagnose it just 618 // once in ActOnMemInitializers. 619 return true; 620 } 621 622 CXXRecordDecl *ClassDecl = Constructor->getParent(); 623 624 // C++ [class.base.init]p2: 625 // Names in a mem-initializer-id are looked up in the scope of the 626 // constructor’s class and, if not found in that scope, are looked 627 // up in the scope containing the constructor’s 628 // definition. [Note: if the constructor’s class contains a member 629 // with the same name as a direct or virtual base class of the 630 // class, a mem-initializer-id naming the member or base class and 631 // composed of a single identifier refers to the class member. A 632 // mem-initializer-id for the hidden base class may be specified 633 // using a qualified name. ] 634 // Look for a member, first. 635 FieldDecl *Member = 0; 636 DeclContext::lookup_result Result = ClassDecl->lookup(MemberOrBase); 637 if (Result.first != Result.second) 638 Member = dyn_cast<FieldDecl>(*Result.first); 639 640 // FIXME: Handle members of an anonymous union. 641 642 if (Member) { 643 // FIXME: Perform direct initialization of the member. 644 return new CXXBaseOrMemberInitializer(Member, (Expr **)Args, NumArgs); 645 } 646 647 // It didn't name a member, so see if it names a class. 648 TypeTy *BaseTy = getTypeName(*MemberOrBase, IdLoc, S, 0/*SS*/); 649 if (!BaseTy) 650 return Diag(IdLoc, diag::err_mem_init_not_member_or_class) 651 << MemberOrBase << SourceRange(IdLoc, RParenLoc); 652 653 QualType BaseType = QualType::getFromOpaquePtr(BaseTy); 654 if (!BaseType->isRecordType()) 655 return Diag(IdLoc, diag::err_base_init_does_not_name_class) 656 << BaseType << SourceRange(IdLoc, RParenLoc); 657 658 // C++ [class.base.init]p2: 659 // [...] Unless the mem-initializer-id names a nonstatic data 660 // member of the constructor’s class or a direct or virtual base 661 // of that class, the mem-initializer is ill-formed. A 662 // mem-initializer-list can initialize a base class using any 663 // name that denotes that base class type. 664 665 // First, check for a direct base class. 666 const CXXBaseSpecifier *DirectBaseSpec = 0; 667 for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin(); 668 Base != ClassDecl->bases_end(); ++Base) { 669 if (Context.getCanonicalType(BaseType).getUnqualifiedType() == 670 Context.getCanonicalType(Base->getType()).getUnqualifiedType()) { 671 // We found a direct base of this type. That's what we're 672 // initializing. 673 DirectBaseSpec = &*Base; 674 break; 675 } 676 } 677 678 // Check for a virtual base class. 679 // FIXME: We might be able to short-circuit this if we know in 680 // advance that there are no virtual bases. 681 const CXXBaseSpecifier *VirtualBaseSpec = 0; 682 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) { 683 // We haven't found a base yet; search the class hierarchy for a 684 // virtual base class. 685 BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 686 /*DetectVirtual=*/false); 687 if (IsDerivedFrom(Context.getTypeDeclType(ClassDecl), BaseType, Paths)) { 688 for (BasePaths::paths_iterator Path = Paths.begin(); 689 Path != Paths.end(); ++Path) { 690 if (Path->back().Base->isVirtual()) { 691 VirtualBaseSpec = Path->back().Base; 692 break; 693 } 694 } 695 } 696 } 697 698 // C++ [base.class.init]p2: 699 // If a mem-initializer-id is ambiguous because it designates both 700 // a direct non-virtual base class and an inherited virtual base 701 // class, the mem-initializer is ill-formed. 702 if (DirectBaseSpec && VirtualBaseSpec) 703 return Diag(IdLoc, diag::err_base_init_direct_and_virtual) 704 << MemberOrBase << SourceRange(IdLoc, RParenLoc); 705 706 return new CXXBaseOrMemberInitializer(BaseType, (Expr **)Args, NumArgs); 707} 708 709void Sema::ActOnMemInitializers(DeclTy *ConstructorDecl, 710 SourceLocation ColonLoc, 711 MemInitTy **MemInits, unsigned NumMemInits) { 712 CXXConstructorDecl *Constructor = 713 dyn_cast<CXXConstructorDecl>((Decl *)ConstructorDecl); 714 715 if (!Constructor) { 716 Diag(ColonLoc, diag::err_only_constructors_take_base_inits); 717 return; 718 } 719} 720 721namespace { 722 /// PureVirtualMethodCollector - traverses a class and its superclasses 723 /// and determines if it has any pure virtual methods. 724 class VISIBILITY_HIDDEN PureVirtualMethodCollector { 725 ASTContext &Context; 726 727 public: 728 typedef llvm::SmallVector<const CXXMethodDecl*, 8> MethodList; 729 730 private: 731 MethodList Methods; 732 733 void Collect(const CXXRecordDecl* RD, MethodList& Methods); 734 735 public: 736 PureVirtualMethodCollector(ASTContext &Ctx, const CXXRecordDecl* RD) 737 : Context(Ctx) { 738 739 MethodList List; 740 Collect(RD, List); 741 742 // Copy the temporary list to methods, and make sure to ignore any 743 // null entries. 744 for (size_t i = 0, e = List.size(); i != e; ++i) { 745 if (List[i]) 746 Methods.push_back(List[i]); 747 } 748 } 749 750 bool empty() const { return Methods.empty(); } 751 752 MethodList::const_iterator methods_begin() { return Methods.begin(); } 753 MethodList::const_iterator methods_end() { return Methods.end(); } 754 }; 755 756 void PureVirtualMethodCollector::Collect(const CXXRecordDecl* RD, 757 MethodList& Methods) { 758 // First, collect the pure virtual methods for the base classes. 759 for (CXXRecordDecl::base_class_const_iterator Base = RD->bases_begin(), 760 BaseEnd = RD->bases_end(); Base != BaseEnd; ++Base) { 761 if (const RecordType *RT = Base->getType()->getAsRecordType()) { 762 const CXXRecordDecl *BaseDecl 763 = cast<CXXRecordDecl>(RT->getDecl()); 764 if (BaseDecl && BaseDecl->isAbstract()) 765 Collect(BaseDecl, Methods); 766 } 767 } 768 769 // Next, zero out any pure virtual methods that this class overrides. 770 for (size_t i = 0, e = Methods.size(); i != e; ++i) { 771 const CXXMethodDecl *VMD = dyn_cast_or_null<CXXMethodDecl>(Methods[i]); 772 if (!VMD) 773 continue; 774 775 DeclContext::lookup_const_iterator I, E; 776 for (llvm::tie(I, E) = RD->lookup(VMD->getDeclName()); I != E; ++I) { 777 if (const CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*I)) { 778 if (Context.getCanonicalType(MD->getType()) == 779 Context.getCanonicalType(VMD->getType())) { 780 // We did find a matching method, which means that this is not a 781 // pure virtual method in the current class. Zero it out. 782 Methods[i] = 0; 783 } 784 } 785 } 786 } 787 788 // Finally, add pure virtual methods from this class. 789 for (RecordDecl::decl_iterator i = RD->decls_begin(), e = RD->decls_end(); 790 i != e; ++i) { 791 if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(*i)) { 792 if (MD->isPure()) 793 Methods.push_back(MD); 794 } 795 } 796 } 797} 798 799bool Sema::RequireNonAbstractType(SourceLocation Loc, QualType T, 800 unsigned DiagID, AbstractDiagSelID SelID, 801 const CXXRecordDecl *CurrentRD) { 802 803 if (!getLangOptions().CPlusPlus) 804 return false; 805 806 if (const ArrayType *AT = Context.getAsArrayType(T)) 807 return RequireNonAbstractType(Loc, AT->getElementType(), DiagID, SelID, 808 CurrentRD); 809 810 if (const PointerType *PT = T->getAsPointerType()) { 811 // Find the innermost pointer type. 812 while (const PointerType *T = PT->getPointeeType()->getAsPointerType()) 813 PT = T; 814 815 if (const ArrayType *AT = Context.getAsArrayType(PT->getPointeeType())) 816 return RequireNonAbstractType(Loc, AT->getElementType(), DiagID, SelID, 817 CurrentRD); 818 } 819 820 const RecordType *RT = T->getAsRecordType(); 821 if (!RT) 822 return false; 823 824 const CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(RT->getDecl()); 825 if (!RD) 826 return false; 827 828 if (CurrentRD && CurrentRD != RD) 829 return false; 830 831 if (!RD->isAbstract()) 832 return false; 833 834 Diag(Loc, DiagID) << RD->getDeclName() << SelID; 835 836 // Check if we've already emitted the list of pure virtual functions for this 837 // class. 838 if (PureVirtualClassDiagSet && PureVirtualClassDiagSet->count(RD)) 839 return true; 840 841 PureVirtualMethodCollector Collector(Context, RD); 842 843 for (PureVirtualMethodCollector::MethodList::const_iterator I = 844 Collector.methods_begin(), E = Collector.methods_end(); I != E; ++I) { 845 const CXXMethodDecl *MD = *I; 846 847 Diag(MD->getLocation(), diag::note_pure_virtual_function) << 848 MD->getDeclName(); 849 } 850 851 if (!PureVirtualClassDiagSet) 852 PureVirtualClassDiagSet.reset(new RecordDeclSetTy); 853 PureVirtualClassDiagSet->insert(RD); 854 855 return true; 856} 857 858namespace { 859 class VISIBILITY_HIDDEN AbstractClassUsageDiagnoser 860 : public DeclVisitor<AbstractClassUsageDiagnoser, bool> { 861 Sema &SemaRef; 862 CXXRecordDecl *AbstractClass; 863 864 bool VisitDeclContext(const DeclContext *DC) { 865 bool Invalid = false; 866 867 for (CXXRecordDecl::decl_iterator I = DC->decls_begin(), 868 E = DC->decls_end(); I != E; ++I) 869 Invalid |= Visit(*I); 870 871 return Invalid; 872 } 873 874 public: 875 AbstractClassUsageDiagnoser(Sema& SemaRef, CXXRecordDecl *ac) 876 : SemaRef(SemaRef), AbstractClass(ac) { 877 Visit(SemaRef.Context.getTranslationUnitDecl()); 878 } 879 880 bool VisitFunctionDecl(const FunctionDecl *FD) { 881 if (FD->isThisDeclarationADefinition()) { 882 // No need to do the check if we're in a definition, because it requires 883 // that the return/param types are complete. 884 // because that requires 885 return VisitDeclContext(FD); 886 } 887 888 // Check the return type. 889 QualType RTy = FD->getType()->getAsFunctionType()->getResultType(); 890 bool Invalid = 891 SemaRef.RequireNonAbstractType(FD->getLocation(), RTy, 892 diag::err_abstract_type_in_decl, 893 Sema::AbstractReturnType, 894 AbstractClass); 895 896 for (FunctionDecl::param_const_iterator I = FD->param_begin(), 897 E = FD->param_end(); I != E; ++I) { 898 const ParmVarDecl *VD = *I; 899 Invalid |= 900 SemaRef.RequireNonAbstractType(VD->getLocation(), 901 VD->getOriginalType(), 902 diag::err_abstract_type_in_decl, 903 Sema::AbstractParamType, 904 AbstractClass); 905 } 906 907 return Invalid; 908 } 909 910 bool VisitDecl(const Decl* D) { 911 if (const DeclContext *DC = dyn_cast<DeclContext>(D)) 912 return VisitDeclContext(DC); 913 914 return false; 915 } 916 }; 917} 918 919void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc, 920 DeclTy *TagDecl, 921 SourceLocation LBrac, 922 SourceLocation RBrac) { 923 TemplateDecl *Template = AdjustDeclIfTemplate(TagDecl); 924 ActOnFields(S, RLoc, TagDecl, 925 (DeclTy**)FieldCollector->getCurFields(), 926 FieldCollector->getCurNumFields(), LBrac, RBrac, 0); 927 928 CXXRecordDecl *RD = cast<CXXRecordDecl>((Decl*)TagDecl); 929 if (!RD->isAbstract()) { 930 // Collect all the pure virtual methods and see if this is an abstract 931 // class after all. 932 PureVirtualMethodCollector Collector(Context, RD); 933 if (!Collector.empty()) 934 RD->setAbstract(true); 935 } 936 937 if (RD->isAbstract()) 938 AbstractClassUsageDiagnoser(*this, RD); 939 940 if (!Template) 941 AddImplicitlyDeclaredMembersToClass(RD); 942} 943 944/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared 945/// special functions, such as the default constructor, copy 946/// constructor, or destructor, to the given C++ class (C++ 947/// [special]p1). This routine can only be executed just before the 948/// definition of the class is complete. 949void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) { 950 QualType ClassType = Context.getTypeDeclType(ClassDecl); 951 ClassType = Context.getCanonicalType(ClassType); 952 953 if (!ClassDecl->hasUserDeclaredConstructor()) { 954 // C++ [class.ctor]p5: 955 // A default constructor for a class X is a constructor of class X 956 // that can be called without an argument. If there is no 957 // user-declared constructor for class X, a default constructor is 958 // implicitly declared. An implicitly-declared default constructor 959 // is an inline public member of its class. 960 DeclarationName Name 961 = Context.DeclarationNames.getCXXConstructorName(ClassType); 962 CXXConstructorDecl *DefaultCon = 963 CXXConstructorDecl::Create(Context, ClassDecl, 964 ClassDecl->getLocation(), Name, 965 Context.getFunctionType(Context.VoidTy, 966 0, 0, false, 0), 967 /*isExplicit=*/false, 968 /*isInline=*/true, 969 /*isImplicitlyDeclared=*/true); 970 DefaultCon->setAccess(AS_public); 971 DefaultCon->setImplicit(); 972 ClassDecl->addDecl(DefaultCon); 973 974 // Notify the class that we've added a constructor. 975 ClassDecl->addedConstructor(Context, DefaultCon); 976 } 977 978 if (!ClassDecl->hasUserDeclaredCopyConstructor()) { 979 // C++ [class.copy]p4: 980 // If the class definition does not explicitly declare a copy 981 // constructor, one is declared implicitly. 982 983 // C++ [class.copy]p5: 984 // The implicitly-declared copy constructor for a class X will 985 // have the form 986 // 987 // X::X(const X&) 988 // 989 // if 990 bool HasConstCopyConstructor = true; 991 992 // -- each direct or virtual base class B of X has a copy 993 // constructor whose first parameter is of type const B& or 994 // const volatile B&, and 995 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 996 HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { 997 const CXXRecordDecl *BaseClassDecl 998 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 999 HasConstCopyConstructor 1000 = BaseClassDecl->hasConstCopyConstructor(Context); 1001 } 1002 1003 // -- for all the nonstatic data members of X that are of a 1004 // class type M (or array thereof), each such class type 1005 // has a copy constructor whose first parameter is of type 1006 // const M& or const volatile M&. 1007 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(); 1008 HasConstCopyConstructor && Field != ClassDecl->field_end(); ++Field) { 1009 QualType FieldType = (*Field)->getType(); 1010 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 1011 FieldType = Array->getElementType(); 1012 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 1013 const CXXRecordDecl *FieldClassDecl 1014 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 1015 HasConstCopyConstructor 1016 = FieldClassDecl->hasConstCopyConstructor(Context); 1017 } 1018 } 1019 1020 // Otherwise, the implicitly declared copy constructor will have 1021 // the form 1022 // 1023 // X::X(X&) 1024 QualType ArgType = ClassType; 1025 if (HasConstCopyConstructor) 1026 ArgType = ArgType.withConst(); 1027 ArgType = Context.getLValueReferenceType(ArgType); 1028 1029 // An implicitly-declared copy constructor is an inline public 1030 // member of its class. 1031 DeclarationName Name 1032 = Context.DeclarationNames.getCXXConstructorName(ClassType); 1033 CXXConstructorDecl *CopyConstructor 1034 = CXXConstructorDecl::Create(Context, ClassDecl, 1035 ClassDecl->getLocation(), Name, 1036 Context.getFunctionType(Context.VoidTy, 1037 &ArgType, 1, 1038 false, 0), 1039 /*isExplicit=*/false, 1040 /*isInline=*/true, 1041 /*isImplicitlyDeclared=*/true); 1042 CopyConstructor->setAccess(AS_public); 1043 CopyConstructor->setImplicit(); 1044 1045 // Add the parameter to the constructor. 1046 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, 1047 ClassDecl->getLocation(), 1048 /*IdentifierInfo=*/0, 1049 ArgType, VarDecl::None, 0); 1050 CopyConstructor->setParams(Context, &FromParam, 1); 1051 1052 ClassDecl->addedConstructor(Context, CopyConstructor); 1053 ClassDecl->addDecl(CopyConstructor); 1054 } 1055 1056 if (!ClassDecl->hasUserDeclaredCopyAssignment()) { 1057 // Note: The following rules are largely analoguous to the copy 1058 // constructor rules. Note that virtual bases are not taken into account 1059 // for determining the argument type of the operator. Note also that 1060 // operators taking an object instead of a reference are allowed. 1061 // 1062 // C++ [class.copy]p10: 1063 // If the class definition does not explicitly declare a copy 1064 // assignment operator, one is declared implicitly. 1065 // The implicitly-defined copy assignment operator for a class X 1066 // will have the form 1067 // 1068 // X& X::operator=(const X&) 1069 // 1070 // if 1071 bool HasConstCopyAssignment = true; 1072 1073 // -- each direct base class B of X has a copy assignment operator 1074 // whose parameter is of type const B&, const volatile B& or B, 1075 // and 1076 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 1077 HasConstCopyAssignment && Base != ClassDecl->bases_end(); ++Base) { 1078 const CXXRecordDecl *BaseClassDecl 1079 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 1080 HasConstCopyAssignment = BaseClassDecl->hasConstCopyAssignment(Context); 1081 } 1082 1083 // -- for all the nonstatic data members of X that are of a class 1084 // type M (or array thereof), each such class type has a copy 1085 // assignment operator whose parameter is of type const M&, 1086 // const volatile M& or M. 1087 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(); 1088 HasConstCopyAssignment && Field != ClassDecl->field_end(); ++Field) { 1089 QualType FieldType = (*Field)->getType(); 1090 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 1091 FieldType = Array->getElementType(); 1092 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 1093 const CXXRecordDecl *FieldClassDecl 1094 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 1095 HasConstCopyAssignment 1096 = FieldClassDecl->hasConstCopyAssignment(Context); 1097 } 1098 } 1099 1100 // Otherwise, the implicitly declared copy assignment operator will 1101 // have the form 1102 // 1103 // X& X::operator=(X&) 1104 QualType ArgType = ClassType; 1105 QualType RetType = Context.getLValueReferenceType(ArgType); 1106 if (HasConstCopyAssignment) 1107 ArgType = ArgType.withConst(); 1108 ArgType = Context.getLValueReferenceType(ArgType); 1109 1110 // An implicitly-declared copy assignment operator is an inline public 1111 // member of its class. 1112 DeclarationName Name = 1113 Context.DeclarationNames.getCXXOperatorName(OO_Equal); 1114 CXXMethodDecl *CopyAssignment = 1115 CXXMethodDecl::Create(Context, ClassDecl, ClassDecl->getLocation(), Name, 1116 Context.getFunctionType(RetType, &ArgType, 1, 1117 false, 0), 1118 /*isStatic=*/false, /*isInline=*/true); 1119 CopyAssignment->setAccess(AS_public); 1120 CopyAssignment->setImplicit(); 1121 1122 // Add the parameter to the operator. 1123 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyAssignment, 1124 ClassDecl->getLocation(), 1125 /*IdentifierInfo=*/0, 1126 ArgType, VarDecl::None, 0); 1127 CopyAssignment->setParams(Context, &FromParam, 1); 1128 1129 // Don't call addedAssignmentOperator. There is no way to distinguish an 1130 // implicit from an explicit assignment operator. 1131 ClassDecl->addDecl(CopyAssignment); 1132 } 1133 1134 if (!ClassDecl->hasUserDeclaredDestructor()) { 1135 // C++ [class.dtor]p2: 1136 // If a class has no user-declared destructor, a destructor is 1137 // declared implicitly. An implicitly-declared destructor is an 1138 // inline public member of its class. 1139 DeclarationName Name 1140 = Context.DeclarationNames.getCXXDestructorName(ClassType); 1141 CXXDestructorDecl *Destructor 1142 = CXXDestructorDecl::Create(Context, ClassDecl, 1143 ClassDecl->getLocation(), Name, 1144 Context.getFunctionType(Context.VoidTy, 1145 0, 0, false, 0), 1146 /*isInline=*/true, 1147 /*isImplicitlyDeclared=*/true); 1148 Destructor->setAccess(AS_public); 1149 Destructor->setImplicit(); 1150 ClassDecl->addDecl(Destructor); 1151 } 1152} 1153 1154/// ActOnStartDelayedCXXMethodDeclaration - We have completed 1155/// parsing a top-level (non-nested) C++ class, and we are now 1156/// parsing those parts of the given Method declaration that could 1157/// not be parsed earlier (C++ [class.mem]p2), such as default 1158/// arguments. This action should enter the scope of the given 1159/// Method declaration as if we had just parsed the qualified method 1160/// name. However, it should not bring the parameters into scope; 1161/// that will be performed by ActOnDelayedCXXMethodParameter. 1162void Sema::ActOnStartDelayedCXXMethodDeclaration(Scope *S, DeclTy *MethodD) { 1163 CXXScopeSpec SS; 1164 FunctionDecl *Method = (FunctionDecl*)MethodD; 1165 QualType ClassTy 1166 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 1167 SS.setScopeRep( 1168 NestedNameSpecifier::Create(Context, 0, false, ClassTy.getTypePtr())); 1169 ActOnCXXEnterDeclaratorScope(S, SS); 1170} 1171 1172/// ActOnDelayedCXXMethodParameter - We've already started a delayed 1173/// C++ method declaration. We're (re-)introducing the given 1174/// function parameter into scope for use in parsing later parts of 1175/// the method declaration. For example, we could see an 1176/// ActOnParamDefaultArgument event for this parameter. 1177void Sema::ActOnDelayedCXXMethodParameter(Scope *S, DeclTy *ParamD) { 1178 ParmVarDecl *Param = (ParmVarDecl*)ParamD; 1179 1180 // If this parameter has an unparsed default argument, clear it out 1181 // to make way for the parsed default argument. 1182 if (Param->hasUnparsedDefaultArg()) 1183 Param->setDefaultArg(0); 1184 1185 S->AddDecl(Param); 1186 if (Param->getDeclName()) 1187 IdResolver.AddDecl(Param); 1188} 1189 1190/// ActOnFinishDelayedCXXMethodDeclaration - We have finished 1191/// processing the delayed method declaration for Method. The method 1192/// declaration is now considered finished. There may be a separate 1193/// ActOnStartOfFunctionDef action later (not necessarily 1194/// immediately!) for this method, if it was also defined inside the 1195/// class body. 1196void Sema::ActOnFinishDelayedCXXMethodDeclaration(Scope *S, DeclTy *MethodD) { 1197 FunctionDecl *Method = (FunctionDecl*)MethodD; 1198 CXXScopeSpec SS; 1199 QualType ClassTy 1200 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 1201 SS.setScopeRep( 1202 NestedNameSpecifier::Create(Context, 0, false, ClassTy.getTypePtr())); 1203 ActOnCXXExitDeclaratorScope(S, SS); 1204 1205 // Now that we have our default arguments, check the constructor 1206 // again. It could produce additional diagnostics or affect whether 1207 // the class has implicitly-declared destructors, among other 1208 // things. 1209 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Method)) { 1210 if (CheckConstructor(Constructor)) 1211 Constructor->setInvalidDecl(); 1212 } 1213 1214 // Check the default arguments, which we may have added. 1215 if (!Method->isInvalidDecl()) 1216 CheckCXXDefaultArguments(Method); 1217} 1218 1219/// CheckConstructorDeclarator - Called by ActOnDeclarator to check 1220/// the well-formedness of the constructor declarator @p D with type @p 1221/// R. If there are any errors in the declarator, this routine will 1222/// emit diagnostics and return true. Otherwise, it will return 1223/// false. Either way, the type @p R will be updated to reflect a 1224/// well-formed type for the constructor. 1225bool Sema::CheckConstructorDeclarator(Declarator &D, QualType &R, 1226 FunctionDecl::StorageClass& SC) { 1227 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 1228 bool isInvalid = false; 1229 1230 // C++ [class.ctor]p3: 1231 // A constructor shall not be virtual (10.3) or static (9.4). A 1232 // constructor can be invoked for a const, volatile or const 1233 // volatile object. A constructor shall not be declared const, 1234 // volatile, or const volatile (9.3.2). 1235 if (isVirtual) { 1236 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be) 1237 << "virtual" << SourceRange(D.getDeclSpec().getVirtualSpecLoc()) 1238 << SourceRange(D.getIdentifierLoc()); 1239 isInvalid = true; 1240 } 1241 if (SC == FunctionDecl::Static) { 1242 Diag(D.getIdentifierLoc(), diag::err_constructor_cannot_be) 1243 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1244 << SourceRange(D.getIdentifierLoc()); 1245 isInvalid = true; 1246 SC = FunctionDecl::None; 1247 } 1248 if (D.getDeclSpec().hasTypeSpecifier()) { 1249 // Constructors don't have return types, but the parser will 1250 // happily parse something like: 1251 // 1252 // class X { 1253 // float X(float); 1254 // }; 1255 // 1256 // The return type will be eliminated later. 1257 Diag(D.getIdentifierLoc(), diag::err_constructor_return_type) 1258 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 1259 << SourceRange(D.getIdentifierLoc()); 1260 } 1261 if (R->getAsFunctionProtoType()->getTypeQuals() != 0) { 1262 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1263 if (FTI.TypeQuals & QualType::Const) 1264 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1265 << "const" << SourceRange(D.getIdentifierLoc()); 1266 if (FTI.TypeQuals & QualType::Volatile) 1267 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1268 << "volatile" << SourceRange(D.getIdentifierLoc()); 1269 if (FTI.TypeQuals & QualType::Restrict) 1270 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_constructor) 1271 << "restrict" << SourceRange(D.getIdentifierLoc()); 1272 } 1273 1274 // Rebuild the function type "R" without any type qualifiers (in 1275 // case any of the errors above fired) and with "void" as the 1276 // return type, since constructors don't have return types. We 1277 // *always* have to do this, because GetTypeForDeclarator will 1278 // put in a result type of "int" when none was specified. 1279 const FunctionProtoType *Proto = R->getAsFunctionProtoType(); 1280 R = Context.getFunctionType(Context.VoidTy, Proto->arg_type_begin(), 1281 Proto->getNumArgs(), 1282 Proto->isVariadic(), 1283 0); 1284 1285 return isInvalid; 1286} 1287 1288/// CheckConstructor - Checks a fully-formed constructor for 1289/// well-formedness, issuing any diagnostics required. Returns true if 1290/// the constructor declarator is invalid. 1291bool Sema::CheckConstructor(CXXConstructorDecl *Constructor) { 1292 CXXRecordDecl *ClassDecl 1293 = dyn_cast<CXXRecordDecl>(Constructor->getDeclContext()); 1294 if (!ClassDecl) 1295 return true; 1296 1297 bool Invalid = Constructor->isInvalidDecl(); 1298 1299 // C++ [class.copy]p3: 1300 // A declaration of a constructor for a class X is ill-formed if 1301 // its first parameter is of type (optionally cv-qualified) X and 1302 // either there are no other parameters or else all other 1303 // parameters have default arguments. 1304 if (!Constructor->isInvalidDecl() && 1305 ((Constructor->getNumParams() == 1) || 1306 (Constructor->getNumParams() > 1 && 1307 Constructor->getParamDecl(1)->getDefaultArg() != 0))) { 1308 QualType ParamType = Constructor->getParamDecl(0)->getType(); 1309 QualType ClassTy = Context.getTagDeclType(ClassDecl); 1310 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { 1311 Diag(Constructor->getLocation(), diag::err_constructor_byvalue_arg) 1312 << SourceRange(Constructor->getParamDecl(0)->getLocation()); 1313 Invalid = true; 1314 } 1315 } 1316 1317 // Notify the class that we've added a constructor. 1318 ClassDecl->addedConstructor(Context, Constructor); 1319 1320 return Invalid; 1321} 1322 1323/// CheckDestructorDeclarator - Called by ActOnDeclarator to check 1324/// the well-formednes of the destructor declarator @p D with type @p 1325/// R. If there are any errors in the declarator, this routine will 1326/// emit diagnostics and return true. Otherwise, it will return 1327/// false. Either way, the type @p R will be updated to reflect a 1328/// well-formed type for the destructor. 1329bool Sema::CheckDestructorDeclarator(Declarator &D, QualType &R, 1330 FunctionDecl::StorageClass& SC) { 1331 bool isInvalid = false; 1332 1333 // C++ [class.dtor]p1: 1334 // [...] A typedef-name that names a class is a class-name 1335 // (7.1.3); however, a typedef-name that names a class shall not 1336 // be used as the identifier in the declarator for a destructor 1337 // declaration. 1338 QualType DeclaratorType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1339 if (DeclaratorType->getAsTypedefType()) { 1340 Diag(D.getIdentifierLoc(), diag::err_destructor_typedef_name) 1341 << DeclaratorType; 1342 isInvalid = true; 1343 } 1344 1345 // C++ [class.dtor]p2: 1346 // A destructor is used to destroy objects of its class type. A 1347 // destructor takes no parameters, and no return type can be 1348 // specified for it (not even void). The address of a destructor 1349 // shall not be taken. A destructor shall not be static. A 1350 // destructor can be invoked for a const, volatile or const 1351 // volatile object. A destructor shall not be declared const, 1352 // volatile or const volatile (9.3.2). 1353 if (SC == FunctionDecl::Static) { 1354 Diag(D.getIdentifierLoc(), diag::err_destructor_cannot_be) 1355 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1356 << SourceRange(D.getIdentifierLoc()); 1357 isInvalid = true; 1358 SC = FunctionDecl::None; 1359 } 1360 if (D.getDeclSpec().hasTypeSpecifier()) { 1361 // Destructors don't have return types, but the parser will 1362 // happily parse something like: 1363 // 1364 // class X { 1365 // float ~X(); 1366 // }; 1367 // 1368 // The return type will be eliminated later. 1369 Diag(D.getIdentifierLoc(), diag::err_destructor_return_type) 1370 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 1371 << SourceRange(D.getIdentifierLoc()); 1372 } 1373 if (R->getAsFunctionProtoType()->getTypeQuals() != 0) { 1374 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1375 if (FTI.TypeQuals & QualType::Const) 1376 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1377 << "const" << SourceRange(D.getIdentifierLoc()); 1378 if (FTI.TypeQuals & QualType::Volatile) 1379 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1380 << "volatile" << SourceRange(D.getIdentifierLoc()); 1381 if (FTI.TypeQuals & QualType::Restrict) 1382 Diag(D.getIdentifierLoc(), diag::err_invalid_qualified_destructor) 1383 << "restrict" << SourceRange(D.getIdentifierLoc()); 1384 } 1385 1386 // Make sure we don't have any parameters. 1387 if (R->getAsFunctionProtoType()->getNumArgs() > 0) { 1388 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params); 1389 1390 // Delete the parameters. 1391 D.getTypeObject(0).Fun.freeArgs(); 1392 } 1393 1394 // Make sure the destructor isn't variadic. 1395 if (R->getAsFunctionProtoType()->isVariadic()) 1396 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic); 1397 1398 // Rebuild the function type "R" without any type qualifiers or 1399 // parameters (in case any of the errors above fired) and with 1400 // "void" as the return type, since destructors don't have return 1401 // types. We *always* have to do this, because GetTypeForDeclarator 1402 // will put in a result type of "int" when none was specified. 1403 R = Context.getFunctionType(Context.VoidTy, 0, 0, false, 0); 1404 1405 return isInvalid; 1406} 1407 1408/// CheckConversionDeclarator - Called by ActOnDeclarator to check the 1409/// well-formednes of the conversion function declarator @p D with 1410/// type @p R. If there are any errors in the declarator, this routine 1411/// will emit diagnostics and return true. Otherwise, it will return 1412/// false. Either way, the type @p R will be updated to reflect a 1413/// well-formed type for the conversion operator. 1414bool Sema::CheckConversionDeclarator(Declarator &D, QualType &R, 1415 FunctionDecl::StorageClass& SC) { 1416 bool isInvalid = false; 1417 1418 // C++ [class.conv.fct]p1: 1419 // Neither parameter types nor return type can be specified. The 1420 // type of a conversion function (8.3.5) is “function taking no 1421 // parameter returning conversion-type-id.” 1422 if (SC == FunctionDecl::Static) { 1423 Diag(D.getIdentifierLoc(), diag::err_conv_function_not_member) 1424 << "static" << SourceRange(D.getDeclSpec().getStorageClassSpecLoc()) 1425 << SourceRange(D.getIdentifierLoc()); 1426 isInvalid = true; 1427 SC = FunctionDecl::None; 1428 } 1429 if (D.getDeclSpec().hasTypeSpecifier()) { 1430 // Conversion functions don't have return types, but the parser will 1431 // happily parse something like: 1432 // 1433 // class X { 1434 // float operator bool(); 1435 // }; 1436 // 1437 // The return type will be changed later anyway. 1438 Diag(D.getIdentifierLoc(), diag::err_conv_function_return_type) 1439 << SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()) 1440 << SourceRange(D.getIdentifierLoc()); 1441 } 1442 1443 // Make sure we don't have any parameters. 1444 if (R->getAsFunctionProtoType()->getNumArgs() > 0) { 1445 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params); 1446 1447 // Delete the parameters. 1448 D.getTypeObject(0).Fun.freeArgs(); 1449 } 1450 1451 // Make sure the conversion function isn't variadic. 1452 if (R->getAsFunctionProtoType()->isVariadic()) 1453 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic); 1454 1455 // C++ [class.conv.fct]p4: 1456 // The conversion-type-id shall not represent a function type nor 1457 // an array type. 1458 QualType ConvType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1459 if (ConvType->isArrayType()) { 1460 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array); 1461 ConvType = Context.getPointerType(ConvType); 1462 } else if (ConvType->isFunctionType()) { 1463 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function); 1464 ConvType = Context.getPointerType(ConvType); 1465 } 1466 1467 // Rebuild the function type "R" without any parameters (in case any 1468 // of the errors above fired) and with the conversion type as the 1469 // return type. 1470 R = Context.getFunctionType(ConvType, 0, 0, false, 1471 R->getAsFunctionProtoType()->getTypeQuals()); 1472 1473 // C++0x explicit conversion operators. 1474 if (D.getDeclSpec().isExplicitSpecified() && !getLangOptions().CPlusPlus0x) 1475 Diag(D.getDeclSpec().getExplicitSpecLoc(), 1476 diag::warn_explicit_conversion_functions) 1477 << SourceRange(D.getDeclSpec().getExplicitSpecLoc()); 1478 1479 return isInvalid; 1480} 1481 1482/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete 1483/// the declaration of the given C++ conversion function. This routine 1484/// is responsible for recording the conversion function in the C++ 1485/// class, if possible. 1486Sema::DeclTy *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) { 1487 assert(Conversion && "Expected to receive a conversion function declaration"); 1488 1489 // Set the lexical context of this conversion function 1490 Conversion->setLexicalDeclContext(CurContext); 1491 1492 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(Conversion->getDeclContext()); 1493 1494 // Make sure we aren't redeclaring the conversion function. 1495 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType()); 1496 1497 // C++ [class.conv.fct]p1: 1498 // [...] A conversion function is never used to convert a 1499 // (possibly cv-qualified) object to the (possibly cv-qualified) 1500 // same object type (or a reference to it), to a (possibly 1501 // cv-qualified) base class of that type (or a reference to it), 1502 // or to (possibly cv-qualified) void. 1503 // FIXME: Suppress this warning if the conversion function ends up 1504 // being a virtual function that overrides a virtual function in a 1505 // base class. 1506 QualType ClassType 1507 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl)); 1508 if (const ReferenceType *ConvTypeRef = ConvType->getAsReferenceType()) 1509 ConvType = ConvTypeRef->getPointeeType(); 1510 if (ConvType->isRecordType()) { 1511 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType(); 1512 if (ConvType == ClassType) 1513 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used) 1514 << ClassType; 1515 else if (IsDerivedFrom(ClassType, ConvType)) 1516 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used) 1517 << ClassType << ConvType; 1518 } else if (ConvType->isVoidType()) { 1519 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used) 1520 << ClassType << ConvType; 1521 } 1522 1523 if (Conversion->getPreviousDeclaration()) { 1524 OverloadedFunctionDecl *Conversions = ClassDecl->getConversionFunctions(); 1525 for (OverloadedFunctionDecl::function_iterator 1526 Conv = Conversions->function_begin(), 1527 ConvEnd = Conversions->function_end(); 1528 Conv != ConvEnd; ++Conv) { 1529 if (*Conv == Conversion->getPreviousDeclaration()) { 1530 *Conv = Conversion; 1531 return (DeclTy *)Conversion; 1532 } 1533 } 1534 assert(Conversion->isInvalidDecl() && "Conversion should not get here."); 1535 } else 1536 ClassDecl->addConversionFunction(Context, Conversion); 1537 1538 return (DeclTy *)Conversion; 1539} 1540 1541//===----------------------------------------------------------------------===// 1542// Namespace Handling 1543//===----------------------------------------------------------------------===// 1544 1545/// ActOnStartNamespaceDef - This is called at the start of a namespace 1546/// definition. 1547Sema::DeclTy *Sema::ActOnStartNamespaceDef(Scope *NamespcScope, 1548 SourceLocation IdentLoc, 1549 IdentifierInfo *II, 1550 SourceLocation LBrace) { 1551 NamespaceDecl *Namespc = 1552 NamespaceDecl::Create(Context, CurContext, IdentLoc, II); 1553 Namespc->setLBracLoc(LBrace); 1554 1555 Scope *DeclRegionScope = NamespcScope->getParent(); 1556 1557 if (II) { 1558 // C++ [namespace.def]p2: 1559 // The identifier in an original-namespace-definition shall not have been 1560 // previously defined in the declarative region in which the 1561 // original-namespace-definition appears. The identifier in an 1562 // original-namespace-definition is the name of the namespace. Subsequently 1563 // in that declarative region, it is treated as an original-namespace-name. 1564 1565 NamedDecl *PrevDecl = LookupName(DeclRegionScope, II, LookupOrdinaryName, 1566 true); 1567 1568 if (NamespaceDecl *OrigNS = dyn_cast_or_null<NamespaceDecl>(PrevDecl)) { 1569 // This is an extended namespace definition. 1570 // Attach this namespace decl to the chain of extended namespace 1571 // definitions. 1572 OrigNS->setNextNamespace(Namespc); 1573 Namespc->setOriginalNamespace(OrigNS->getOriginalNamespace()); 1574 1575 // Remove the previous declaration from the scope. 1576 if (DeclRegionScope->isDeclScope(OrigNS)) { 1577 IdResolver.RemoveDecl(OrigNS); 1578 DeclRegionScope->RemoveDecl(OrigNS); 1579 } 1580 } else if (PrevDecl) { 1581 // This is an invalid name redefinition. 1582 Diag(Namespc->getLocation(), diag::err_redefinition_different_kind) 1583 << Namespc->getDeclName(); 1584 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 1585 Namespc->setInvalidDecl(); 1586 // Continue on to push Namespc as current DeclContext and return it. 1587 } 1588 1589 PushOnScopeChains(Namespc, DeclRegionScope); 1590 } else { 1591 // FIXME: Handle anonymous namespaces 1592 } 1593 1594 // Although we could have an invalid decl (i.e. the namespace name is a 1595 // redefinition), push it as current DeclContext and try to continue parsing. 1596 // FIXME: We should be able to push Namespc here, so that the 1597 // each DeclContext for the namespace has the declarations 1598 // that showed up in that particular namespace definition. 1599 PushDeclContext(NamespcScope, Namespc); 1600 return Namespc; 1601} 1602 1603/// ActOnFinishNamespaceDef - This callback is called after a namespace is 1604/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. 1605void Sema::ActOnFinishNamespaceDef(DeclTy *D, SourceLocation RBrace) { 1606 Decl *Dcl = static_cast<Decl *>(D); 1607 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); 1608 assert(Namespc && "Invalid parameter, expected NamespaceDecl"); 1609 Namespc->setRBracLoc(RBrace); 1610 PopDeclContext(); 1611} 1612 1613Sema::DeclTy *Sema::ActOnUsingDirective(Scope *S, 1614 SourceLocation UsingLoc, 1615 SourceLocation NamespcLoc, 1616 const CXXScopeSpec &SS, 1617 SourceLocation IdentLoc, 1618 IdentifierInfo *NamespcName, 1619 AttributeList *AttrList) { 1620 assert(!SS.isInvalid() && "Invalid CXXScopeSpec."); 1621 assert(NamespcName && "Invalid NamespcName."); 1622 assert(IdentLoc.isValid() && "Invalid NamespceName location."); 1623 assert(S->getFlags() & Scope::DeclScope && "Invalid Scope."); 1624 1625 UsingDirectiveDecl *UDir = 0; 1626 1627 // Lookup namespace name. 1628 LookupResult R = LookupParsedName(S, &SS, NamespcName, 1629 LookupNamespaceName, false); 1630 if (R.isAmbiguous()) { 1631 DiagnoseAmbiguousLookup(R, NamespcName, IdentLoc); 1632 return 0; 1633 } 1634 if (NamedDecl *NS = R) { 1635 assert(isa<NamespaceDecl>(NS) && "expected namespace decl"); 1636 // C++ [namespace.udir]p1: 1637 // A using-directive specifies that the names in the nominated 1638 // namespace can be used in the scope in which the 1639 // using-directive appears after the using-directive. During 1640 // unqualified name lookup (3.4.1), the names appear as if they 1641 // were declared in the nearest enclosing namespace which 1642 // contains both the using-directive and the nominated 1643 // namespace. [Note: in this context, “contains” means “contains 1644 // directly or indirectly”. ] 1645 1646 // Find enclosing context containing both using-directive and 1647 // nominated namespace. 1648 DeclContext *CommonAncestor = cast<DeclContext>(NS); 1649 while (CommonAncestor && !CommonAncestor->Encloses(CurContext)) 1650 CommonAncestor = CommonAncestor->getParent(); 1651 1652 UDir = UsingDirectiveDecl::Create(Context, CurContext, UsingLoc, 1653 NamespcLoc, IdentLoc, 1654 cast<NamespaceDecl>(NS), 1655 CommonAncestor); 1656 PushUsingDirective(S, UDir); 1657 } else { 1658 Diag(IdentLoc, diag::err_expected_namespace_name) << SS.getRange(); 1659 } 1660 1661 // FIXME: We ignore attributes for now. 1662 delete AttrList; 1663 return UDir; 1664} 1665 1666void Sema::PushUsingDirective(Scope *S, UsingDirectiveDecl *UDir) { 1667 // If scope has associated entity, then using directive is at namespace 1668 // or translation unit scope. We add UsingDirectiveDecls, into 1669 // it's lookup structure. 1670 if (DeclContext *Ctx = static_cast<DeclContext*>(S->getEntity())) 1671 Ctx->addDecl(UDir); 1672 else 1673 // Otherwise it is block-sope. using-directives will affect lookup 1674 // only to the end of scope. 1675 S->PushUsingDirective(UDir); 1676} 1677 1678Sema::DeclTy *Sema::ActOnNamespaceAliasDef(Scope *S, 1679 SourceLocation AliasLoc, 1680 IdentifierInfo *Alias, 1681 const CXXScopeSpec &SS, 1682 SourceLocation NamespaceLoc, 1683 IdentifierInfo *NamespaceName) { 1684 1685 // Check if we have a previous declaration with the same name. 1686 if (NamedDecl *PrevDecl = LookupName(S, Alias, LookupOrdinaryName)) { 1687 // FIXME: If this is a namespace alias decl, and it points to the same 1688 // namespace, we shouldn't warn. 1689 unsigned DiagID = isa<NamespaceDecl>(PrevDecl) ? diag::err_redefinition : 1690 diag::err_redefinition_different_kind; 1691 Diag(AliasLoc, DiagID) << Alias; 1692 Diag(PrevDecl->getLocation(), diag::note_previous_definition); 1693 return 0; 1694 } 1695 1696 return 0; 1697} 1698 1699/// AddCXXDirectInitializerToDecl - This action is called immediately after 1700/// ActOnDeclarator, when a C++ direct initializer is present. 1701/// e.g: "int x(1);" 1702void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc, 1703 MultiExprArg Exprs, 1704 SourceLocation *CommaLocs, 1705 SourceLocation RParenLoc) { 1706 unsigned NumExprs = Exprs.size(); 1707 assert(NumExprs != 0 && Exprs.get() && "missing expressions"); 1708 Decl *RealDecl = static_cast<Decl *>(Dcl); 1709 1710 // If there is no declaration, there was an error parsing it. Just ignore 1711 // the initializer. 1712 if (RealDecl == 0) { 1713 return; 1714 } 1715 1716 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1717 if (!VDecl) { 1718 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 1719 RealDecl->setInvalidDecl(); 1720 return; 1721 } 1722 1723 // FIXME: Need to handle dependent types and expressions here. 1724 1725 // We will treat direct-initialization as a copy-initialization: 1726 // int x(1); -as-> int x = 1; 1727 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); 1728 // 1729 // Clients that want to distinguish between the two forms, can check for 1730 // direct initializer using VarDecl::hasCXXDirectInitializer(). 1731 // A major benefit is that clients that don't particularly care about which 1732 // exactly form was it (like the CodeGen) can handle both cases without 1733 // special case code. 1734 1735 // C++ 8.5p11: 1736 // The form of initialization (using parentheses or '=') is generally 1737 // insignificant, but does matter when the entity being initialized has a 1738 // class type. 1739 QualType DeclInitType = VDecl->getType(); 1740 if (const ArrayType *Array = Context.getAsArrayType(DeclInitType)) 1741 DeclInitType = Array->getElementType(); 1742 1743 // FIXME: This isn't the right place to complete the type. 1744 if (RequireCompleteType(VDecl->getLocation(), VDecl->getType(), 1745 diag::err_typecheck_decl_incomplete_type)) { 1746 VDecl->setInvalidDecl(); 1747 return; 1748 } 1749 1750 if (VDecl->getType()->isRecordType()) { 1751 CXXConstructorDecl *Constructor 1752 = PerformInitializationByConstructor(DeclInitType, 1753 (Expr **)Exprs.get(), NumExprs, 1754 VDecl->getLocation(), 1755 SourceRange(VDecl->getLocation(), 1756 RParenLoc), 1757 VDecl->getDeclName(), 1758 IK_Direct); 1759 if (!Constructor) 1760 RealDecl->setInvalidDecl(); 1761 else 1762 Exprs.release(); 1763 1764 // Let clients know that initialization was done with a direct 1765 // initializer. 1766 VDecl->setCXXDirectInitializer(true); 1767 1768 // FIXME: Add ExprTys and Constructor to the RealDecl as part of 1769 // the initializer. 1770 return; 1771 } 1772 1773 if (NumExprs > 1) { 1774 Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg) 1775 << SourceRange(VDecl->getLocation(), RParenLoc); 1776 RealDecl->setInvalidDecl(); 1777 return; 1778 } 1779 1780 // Let clients know that initialization was done with a direct initializer. 1781 VDecl->setCXXDirectInitializer(true); 1782 1783 assert(NumExprs == 1 && "Expected 1 expression"); 1784 // Set the init expression, handles conversions. 1785 AddInitializerToDecl(Dcl, ExprArg(*this, Exprs.release()[0]), 1786 /*DirectInit=*/true); 1787} 1788 1789/// PerformInitializationByConstructor - Perform initialization by 1790/// constructor (C++ [dcl.init]p14), which may occur as part of 1791/// direct-initialization or copy-initialization. We are initializing 1792/// an object of type @p ClassType with the given arguments @p 1793/// Args. @p Loc is the location in the source code where the 1794/// initializer occurs (e.g., a declaration, member initializer, 1795/// functional cast, etc.) while @p Range covers the whole 1796/// initialization. @p InitEntity is the entity being initialized, 1797/// which may by the name of a declaration or a type. @p Kind is the 1798/// kind of initialization we're performing, which affects whether 1799/// explicit constructors will be considered. When successful, returns 1800/// the constructor that will be used to perform the initialization; 1801/// when the initialization fails, emits a diagnostic and returns 1802/// null. 1803CXXConstructorDecl * 1804Sema::PerformInitializationByConstructor(QualType ClassType, 1805 Expr **Args, unsigned NumArgs, 1806 SourceLocation Loc, SourceRange Range, 1807 DeclarationName InitEntity, 1808 InitializationKind Kind) { 1809 const RecordType *ClassRec = ClassType->getAsRecordType(); 1810 assert(ClassRec && "Can only initialize a class type here"); 1811 1812 // C++ [dcl.init]p14: 1813 // 1814 // If the initialization is direct-initialization, or if it is 1815 // copy-initialization where the cv-unqualified version of the 1816 // source type is the same class as, or a derived class of, the 1817 // class of the destination, constructors are considered. The 1818 // applicable constructors are enumerated (13.3.1.3), and the 1819 // best one is chosen through overload resolution (13.3). The 1820 // constructor so selected is called to initialize the object, 1821 // with the initializer expression(s) as its argument(s). If no 1822 // constructor applies, or the overload resolution is ambiguous, 1823 // the initialization is ill-formed. 1824 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1825 OverloadCandidateSet CandidateSet; 1826 1827 // Add constructors to the overload set. 1828 DeclarationName ConstructorName 1829 = Context.DeclarationNames.getCXXConstructorName( 1830 Context.getCanonicalType(ClassType.getUnqualifiedType())); 1831 DeclContext::lookup_const_iterator Con, ConEnd; 1832 for (llvm::tie(Con, ConEnd) = ClassDecl->lookup(ConstructorName); 1833 Con != ConEnd; ++Con) { 1834 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 1835 if ((Kind == IK_Direct) || 1836 (Kind == IK_Copy && Constructor->isConvertingConstructor()) || 1837 (Kind == IK_Default && Constructor->isDefaultConstructor())) 1838 AddOverloadCandidate(Constructor, Args, NumArgs, CandidateSet); 1839 } 1840 1841 // FIXME: When we decide not to synthesize the implicitly-declared 1842 // constructors, we'll need to make them appear here. 1843 1844 OverloadCandidateSet::iterator Best; 1845 switch (BestViableFunction(CandidateSet, Best)) { 1846 case OR_Success: 1847 // We found a constructor. Return it. 1848 return cast<CXXConstructorDecl>(Best->Function); 1849 1850 case OR_No_Viable_Function: 1851 if (InitEntity) 1852 Diag(Loc, diag::err_ovl_no_viable_function_in_init) 1853 << InitEntity << Range; 1854 else 1855 Diag(Loc, diag::err_ovl_no_viable_function_in_init) 1856 << ClassType << Range; 1857 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1858 return 0; 1859 1860 case OR_Ambiguous: 1861 if (InitEntity) 1862 Diag(Loc, diag::err_ovl_ambiguous_init) << InitEntity << Range; 1863 else 1864 Diag(Loc, diag::err_ovl_ambiguous_init) << ClassType << Range; 1865 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1866 return 0; 1867 1868 case OR_Deleted: 1869 if (InitEntity) 1870 Diag(Loc, diag::err_ovl_deleted_init) 1871 << Best->Function->isDeleted() 1872 << InitEntity << Range; 1873 else 1874 Diag(Loc, diag::err_ovl_deleted_init) 1875 << Best->Function->isDeleted() 1876 << InitEntity << Range; 1877 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1878 return 0; 1879 } 1880 1881 return 0; 1882} 1883 1884/// CompareReferenceRelationship - Compare the two types T1 and T2 to 1885/// determine whether they are reference-related, 1886/// reference-compatible, reference-compatible with added 1887/// qualification, or incompatible, for use in C++ initialization by 1888/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 1889/// type, and the first type (T1) is the pointee type of the reference 1890/// type being initialized. 1891Sema::ReferenceCompareResult 1892Sema::CompareReferenceRelationship(QualType T1, QualType T2, 1893 bool& DerivedToBase) { 1894 assert(!T1->isReferenceType() && 1895 "T1 must be the pointee type of the reference type"); 1896 assert(!T2->isReferenceType() && "T2 cannot be a reference type"); 1897 1898 T1 = Context.getCanonicalType(T1); 1899 T2 = Context.getCanonicalType(T2); 1900 QualType UnqualT1 = T1.getUnqualifiedType(); 1901 QualType UnqualT2 = T2.getUnqualifiedType(); 1902 1903 // C++ [dcl.init.ref]p4: 1904 // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is 1905 // reference-related to “cv2 T2” if T1 is the same type as T2, or 1906 // T1 is a base class of T2. 1907 if (UnqualT1 == UnqualT2) 1908 DerivedToBase = false; 1909 else if (IsDerivedFrom(UnqualT2, UnqualT1)) 1910 DerivedToBase = true; 1911 else 1912 return Ref_Incompatible; 1913 1914 // At this point, we know that T1 and T2 are reference-related (at 1915 // least). 1916 1917 // C++ [dcl.init.ref]p4: 1918 // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is 1919 // reference-related to T2 and cv1 is the same cv-qualification 1920 // as, or greater cv-qualification than, cv2. For purposes of 1921 // overload resolution, cases for which cv1 is greater 1922 // cv-qualification than cv2 are identified as 1923 // reference-compatible with added qualification (see 13.3.3.2). 1924 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 1925 return Ref_Compatible; 1926 else if (T1.isMoreQualifiedThan(T2)) 1927 return Ref_Compatible_With_Added_Qualification; 1928 else 1929 return Ref_Related; 1930} 1931 1932/// CheckReferenceInit - Check the initialization of a reference 1933/// variable with the given initializer (C++ [dcl.init.ref]). Init is 1934/// the initializer (either a simple initializer or an initializer 1935/// list), and DeclType is the type of the declaration. When ICS is 1936/// non-null, this routine will compute the implicit conversion 1937/// sequence according to C++ [over.ics.ref] and will not produce any 1938/// diagnostics; when ICS is null, it will emit diagnostics when any 1939/// errors are found. Either way, a return value of true indicates 1940/// that there was a failure, a return value of false indicates that 1941/// the reference initialization succeeded. 1942/// 1943/// When @p SuppressUserConversions, user-defined conversions are 1944/// suppressed. 1945/// When @p AllowExplicit, we also permit explicit user-defined 1946/// conversion functions. 1947bool 1948Sema::CheckReferenceInit(Expr *&Init, QualType &DeclType, 1949 ImplicitConversionSequence *ICS, 1950 bool SuppressUserConversions, 1951 bool AllowExplicit) { 1952 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 1953 1954 QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); 1955 QualType T2 = Init->getType(); 1956 1957 // If the initializer is the address of an overloaded function, try 1958 // to resolve the overloaded function. If all goes well, T2 is the 1959 // type of the resulting function. 1960 if (Context.getCanonicalType(T2) == Context.OverloadTy) { 1961 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Init, DeclType, 1962 ICS != 0); 1963 if (Fn) { 1964 // Since we're performing this reference-initialization for 1965 // real, update the initializer with the resulting function. 1966 if (!ICS) { 1967 if (DiagnoseUseOfDecl(Fn, Init->getSourceRange().getBegin())) 1968 return true; 1969 1970 FixOverloadedFunctionReference(Init, Fn); 1971 } 1972 1973 T2 = Fn->getType(); 1974 } 1975 } 1976 1977 // Compute some basic properties of the types and the initializer. 1978 bool isRValRef = DeclType->isRValueReferenceType(); 1979 bool DerivedToBase = false; 1980 Expr::isLvalueResult InitLvalue = Init->isLvalue(Context); 1981 ReferenceCompareResult RefRelationship 1982 = CompareReferenceRelationship(T1, T2, DerivedToBase); 1983 1984 // Most paths end in a failed conversion. 1985 if (ICS) 1986 ICS->ConversionKind = ImplicitConversionSequence::BadConversion; 1987 1988 // C++ [dcl.init.ref]p5: 1989 // A reference to type “cv1 T1” is initialized by an expression 1990 // of type “cv2 T2” as follows: 1991 1992 // -- If the initializer expression 1993 1994 bool BindsDirectly = false; 1995 // -- is an lvalue (but is not a bit-field), and “cv1 T1” is 1996 // reference-compatible with “cv2 T2,” or 1997 // 1998 // Note that the bit-field check is skipped if we are just computing 1999 // the implicit conversion sequence (C++ [over.best.ics]p2). 2000 if (InitLvalue == Expr::LV_Valid && (ICS || !Init->isBitField()) && 2001 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 2002 BindsDirectly = true; 2003 2004 // Rvalue references cannot bind to lvalues (N2812). 2005 if (isRValRef) { 2006 if (!ICS) 2007 Diag(Init->getSourceRange().getBegin(), diag::err_lvalue_to_rvalue_ref) 2008 << Init->getSourceRange(); 2009 return true; 2010 } 2011 2012 if (ICS) { 2013 // C++ [over.ics.ref]p1: 2014 // When a parameter of reference type binds directly (8.5.3) 2015 // to an argument expression, the implicit conversion sequence 2016 // is the identity conversion, unless the argument expression 2017 // has a type that is a derived class of the parameter type, 2018 // in which case the implicit conversion sequence is a 2019 // derived-to-base Conversion (13.3.3.1). 2020 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 2021 ICS->Standard.First = ICK_Identity; 2022 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 2023 ICS->Standard.Third = ICK_Identity; 2024 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 2025 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 2026 ICS->Standard.ReferenceBinding = true; 2027 ICS->Standard.DirectBinding = true; 2028 2029 // Nothing more to do: the inaccessibility/ambiguity check for 2030 // derived-to-base conversions is suppressed when we're 2031 // computing the implicit conversion sequence (C++ 2032 // [over.best.ics]p2). 2033 return false; 2034 } else { 2035 // Perform the conversion. 2036 // FIXME: Binding to a subobject of the lvalue is going to require 2037 // more AST annotation than this. 2038 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 2039 } 2040 } 2041 2042 // -- has a class type (i.e., T2 is a class type) and can be 2043 // implicitly converted to an lvalue of type “cv3 T3,” 2044 // where “cv1 T1” is reference-compatible with “cv3 T3” 2045 // 92) (this conversion is selected by enumerating the 2046 // applicable conversion functions (13.3.1.6) and choosing 2047 // the best one through overload resolution (13.3)), 2048 if (!isRValRef && !SuppressUserConversions && T2->isRecordType()) { 2049 // FIXME: Look for conversions in base classes! 2050 CXXRecordDecl *T2RecordDecl 2051 = dyn_cast<CXXRecordDecl>(T2->getAsRecordType()->getDecl()); 2052 2053 OverloadCandidateSet CandidateSet; 2054 OverloadedFunctionDecl *Conversions 2055 = T2RecordDecl->getConversionFunctions(); 2056 for (OverloadedFunctionDecl::function_iterator Func 2057 = Conversions->function_begin(); 2058 Func != Conversions->function_end(); ++Func) { 2059 CXXConversionDecl *Conv = cast<CXXConversionDecl>(*Func); 2060 2061 // If the conversion function doesn't return a reference type, 2062 // it can't be considered for this conversion. 2063 if (Conv->getConversionType()->isLValueReferenceType() && 2064 (AllowExplicit || !Conv->isExplicit())) 2065 AddConversionCandidate(Conv, Init, DeclType, CandidateSet); 2066 } 2067 2068 OverloadCandidateSet::iterator Best; 2069 switch (BestViableFunction(CandidateSet, Best)) { 2070 case OR_Success: 2071 // This is a direct binding. 2072 BindsDirectly = true; 2073 2074 if (ICS) { 2075 // C++ [over.ics.ref]p1: 2076 // 2077 // [...] If the parameter binds directly to the result of 2078 // applying a conversion function to the argument 2079 // expression, the implicit conversion sequence is a 2080 // user-defined conversion sequence (13.3.3.1.2), with the 2081 // second standard conversion sequence either an identity 2082 // conversion or, if the conversion function returns an 2083 // entity of a type that is a derived class of the parameter 2084 // type, a derived-to-base Conversion. 2085 ICS->ConversionKind = ImplicitConversionSequence::UserDefinedConversion; 2086 ICS->UserDefined.Before = Best->Conversions[0].Standard; 2087 ICS->UserDefined.After = Best->FinalConversion; 2088 ICS->UserDefined.ConversionFunction = Best->Function; 2089 assert(ICS->UserDefined.After.ReferenceBinding && 2090 ICS->UserDefined.After.DirectBinding && 2091 "Expected a direct reference binding!"); 2092 return false; 2093 } else { 2094 // Perform the conversion. 2095 // FIXME: Binding to a subobject of the lvalue is going to require 2096 // more AST annotation than this. 2097 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 2098 } 2099 break; 2100 2101 case OR_Ambiguous: 2102 assert(false && "Ambiguous reference binding conversions not implemented."); 2103 return true; 2104 2105 case OR_No_Viable_Function: 2106 case OR_Deleted: 2107 // There was no suitable conversion, or we found a deleted 2108 // conversion; continue with other checks. 2109 break; 2110 } 2111 } 2112 2113 if (BindsDirectly) { 2114 // C++ [dcl.init.ref]p4: 2115 // [...] In all cases where the reference-related or 2116 // reference-compatible relationship of two types is used to 2117 // establish the validity of a reference binding, and T1 is a 2118 // base class of T2, a program that necessitates such a binding 2119 // is ill-formed if T1 is an inaccessible (clause 11) or 2120 // ambiguous (10.2) base class of T2. 2121 // 2122 // Note that we only check this condition when we're allowed to 2123 // complain about errors, because we should not be checking for 2124 // ambiguity (or inaccessibility) unless the reference binding 2125 // actually happens. 2126 if (DerivedToBase) 2127 return CheckDerivedToBaseConversion(T2, T1, 2128 Init->getSourceRange().getBegin(), 2129 Init->getSourceRange()); 2130 else 2131 return false; 2132 } 2133 2134 // -- Otherwise, the reference shall be to a non-volatile const 2135 // type (i.e., cv1 shall be const), or shall be an rvalue reference. 2136 if (!isRValRef && T1.getCVRQualifiers() != QualType::Const) { 2137 if (!ICS) 2138 Diag(Init->getSourceRange().getBegin(), 2139 diag::err_not_reference_to_const_init) 2140 << T1 << (InitLvalue != Expr::LV_Valid? "temporary" : "value") 2141 << T2 << Init->getSourceRange(); 2142 return true; 2143 } 2144 2145 // -- If the initializer expression is an rvalue, with T2 a 2146 // class type, and “cv1 T1” is reference-compatible with 2147 // “cv2 T2,” the reference is bound in one of the 2148 // following ways (the choice is implementation-defined): 2149 // 2150 // -- The reference is bound to the object represented by 2151 // the rvalue (see 3.10) or to a sub-object within that 2152 // object. 2153 // 2154 // -- A temporary of type “cv1 T2” [sic] is created, and 2155 // a constructor is called to copy the entire rvalue 2156 // object into the temporary. The reference is bound to 2157 // the temporary or to a sub-object within the 2158 // temporary. 2159 // 2160 // The constructor that would be used to make the copy 2161 // shall be callable whether or not the copy is actually 2162 // done. 2163 // 2164 // Note that C++0x [dcl.ref.init]p5 takes away this implementation 2165 // freedom, so we will always take the first option and never build 2166 // a temporary in this case. FIXME: We will, however, have to check 2167 // for the presence of a copy constructor in C++98/03 mode. 2168 if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && 2169 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 2170 if (ICS) { 2171 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 2172 ICS->Standard.First = ICK_Identity; 2173 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 2174 ICS->Standard.Third = ICK_Identity; 2175 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 2176 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 2177 ICS->Standard.ReferenceBinding = true; 2178 ICS->Standard.DirectBinding = false; 2179 } else { 2180 // FIXME: Binding to a subobject of the rvalue is going to require 2181 // more AST annotation than this. 2182 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 2183 } 2184 return false; 2185 } 2186 2187 // -- Otherwise, a temporary of type “cv1 T1” is created and 2188 // initialized from the initializer expression using the 2189 // rules for a non-reference copy initialization (8.5). The 2190 // reference is then bound to the temporary. If T1 is 2191 // reference-related to T2, cv1 must be the same 2192 // cv-qualification as, or greater cv-qualification than, 2193 // cv2; otherwise, the program is ill-formed. 2194 if (RefRelationship == Ref_Related) { 2195 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 2196 // we would be reference-compatible or reference-compatible with 2197 // added qualification. But that wasn't the case, so the reference 2198 // initialization fails. 2199 if (!ICS) 2200 Diag(Init->getSourceRange().getBegin(), 2201 diag::err_reference_init_drops_quals) 2202 << T1 << (InitLvalue != Expr::LV_Valid? "temporary" : "value") 2203 << T2 << Init->getSourceRange(); 2204 return true; 2205 } 2206 2207 // If at least one of the types is a class type, the types are not 2208 // related, and we aren't allowed any user conversions, the 2209 // reference binding fails. This case is important for breaking 2210 // recursion, since TryImplicitConversion below will attempt to 2211 // create a temporary through the use of a copy constructor. 2212 if (SuppressUserConversions && RefRelationship == Ref_Incompatible && 2213 (T1->isRecordType() || T2->isRecordType())) { 2214 if (!ICS) 2215 Diag(Init->getSourceRange().getBegin(), 2216 diag::err_typecheck_convert_incompatible) 2217 << DeclType << Init->getType() << "initializing" << Init->getSourceRange(); 2218 return true; 2219 } 2220 2221 // Actually try to convert the initializer to T1. 2222 if (ICS) { 2223 /// C++ [over.ics.ref]p2: 2224 /// 2225 /// When a parameter of reference type is not bound directly to 2226 /// an argument expression, the conversion sequence is the one 2227 /// required to convert the argument expression to the 2228 /// underlying type of the reference according to 2229 /// 13.3.3.1. Conceptually, this conversion sequence corresponds 2230 /// to copy-initializing a temporary of the underlying type with 2231 /// the argument expression. Any difference in top-level 2232 /// cv-qualification is subsumed by the initialization itself 2233 /// and does not constitute a conversion. 2234 *ICS = TryImplicitConversion(Init, T1, SuppressUserConversions); 2235 return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; 2236 } else { 2237 return PerformImplicitConversion(Init, T1, "initializing"); 2238 } 2239} 2240 2241/// CheckOverloadedOperatorDeclaration - Check whether the declaration 2242/// of this overloaded operator is well-formed. If so, returns false; 2243/// otherwise, emits appropriate diagnostics and returns true. 2244bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) { 2245 assert(FnDecl && FnDecl->isOverloadedOperator() && 2246 "Expected an overloaded operator declaration"); 2247 2248 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator(); 2249 2250 // C++ [over.oper]p5: 2251 // The allocation and deallocation functions, operator new, 2252 // operator new[], operator delete and operator delete[], are 2253 // described completely in 3.7.3. The attributes and restrictions 2254 // found in the rest of this subclause do not apply to them unless 2255 // explicitly stated in 3.7.3. 2256 // FIXME: Write a separate routine for checking this. For now, just 2257 // allow it. 2258 if (Op == OO_New || Op == OO_Array_New || 2259 Op == OO_Delete || Op == OO_Array_Delete) 2260 return false; 2261 2262 // C++ [over.oper]p6: 2263 // An operator function shall either be a non-static member 2264 // function or be a non-member function and have at least one 2265 // parameter whose type is a class, a reference to a class, an 2266 // enumeration, or a reference to an enumeration. 2267 if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl)) { 2268 if (MethodDecl->isStatic()) 2269 return Diag(FnDecl->getLocation(), 2270 diag::err_operator_overload_static) << FnDecl->getDeclName(); 2271 } else { 2272 bool ClassOrEnumParam = false; 2273 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(), 2274 ParamEnd = FnDecl->param_end(); 2275 Param != ParamEnd; ++Param) { 2276 QualType ParamType = (*Param)->getType().getNonReferenceType(); 2277 if (ParamType->isRecordType() || ParamType->isEnumeralType()) { 2278 ClassOrEnumParam = true; 2279 break; 2280 } 2281 } 2282 2283 if (!ClassOrEnumParam) 2284 return Diag(FnDecl->getLocation(), 2285 diag::err_operator_overload_needs_class_or_enum) 2286 << FnDecl->getDeclName(); 2287 } 2288 2289 // C++ [over.oper]p8: 2290 // An operator function cannot have default arguments (8.3.6), 2291 // except where explicitly stated below. 2292 // 2293 // Only the function-call operator allows default arguments 2294 // (C++ [over.call]p1). 2295 if (Op != OO_Call) { 2296 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 2297 Param != FnDecl->param_end(); ++Param) { 2298 if ((*Param)->hasUnparsedDefaultArg()) 2299 return Diag((*Param)->getLocation(), 2300 diag::err_operator_overload_default_arg) 2301 << FnDecl->getDeclName(); 2302 else if (Expr *DefArg = (*Param)->getDefaultArg()) 2303 return Diag((*Param)->getLocation(), 2304 diag::err_operator_overload_default_arg) 2305 << FnDecl->getDeclName() << DefArg->getSourceRange(); 2306 } 2307 } 2308 2309 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = { 2310 { false, false, false } 2311#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \ 2312 , { Unary, Binary, MemberOnly } 2313#include "clang/Basic/OperatorKinds.def" 2314 }; 2315 2316 bool CanBeUnaryOperator = OperatorUses[Op][0]; 2317 bool CanBeBinaryOperator = OperatorUses[Op][1]; 2318 bool MustBeMemberOperator = OperatorUses[Op][2]; 2319 2320 // C++ [over.oper]p8: 2321 // [...] Operator functions cannot have more or fewer parameters 2322 // than the number required for the corresponding operator, as 2323 // described in the rest of this subclause. 2324 unsigned NumParams = FnDecl->getNumParams() 2325 + (isa<CXXMethodDecl>(FnDecl)? 1 : 0); 2326 if (Op != OO_Call && 2327 ((NumParams == 1 && !CanBeUnaryOperator) || 2328 (NumParams == 2 && !CanBeBinaryOperator) || 2329 (NumParams < 1) || (NumParams > 2))) { 2330 // We have the wrong number of parameters. 2331 unsigned ErrorKind; 2332 if (CanBeUnaryOperator && CanBeBinaryOperator) { 2333 ErrorKind = 2; // 2 -> unary or binary. 2334 } else if (CanBeUnaryOperator) { 2335 ErrorKind = 0; // 0 -> unary 2336 } else { 2337 assert(CanBeBinaryOperator && 2338 "All non-call overloaded operators are unary or binary!"); 2339 ErrorKind = 1; // 1 -> binary 2340 } 2341 2342 return Diag(FnDecl->getLocation(), diag::err_operator_overload_must_be) 2343 << FnDecl->getDeclName() << NumParams << ErrorKind; 2344 } 2345 2346 // Overloaded operators other than operator() cannot be variadic. 2347 if (Op != OO_Call && 2348 FnDecl->getType()->getAsFunctionProtoType()->isVariadic()) { 2349 return Diag(FnDecl->getLocation(), diag::err_operator_overload_variadic) 2350 << FnDecl->getDeclName(); 2351 } 2352 2353 // Some operators must be non-static member functions. 2354 if (MustBeMemberOperator && !isa<CXXMethodDecl>(FnDecl)) { 2355 return Diag(FnDecl->getLocation(), 2356 diag::err_operator_overload_must_be_member) 2357 << FnDecl->getDeclName(); 2358 } 2359 2360 // C++ [over.inc]p1: 2361 // The user-defined function called operator++ implements the 2362 // prefix and postfix ++ operator. If this function is a member 2363 // function with no parameters, or a non-member function with one 2364 // parameter of class or enumeration type, it defines the prefix 2365 // increment operator ++ for objects of that type. If the function 2366 // is a member function with one parameter (which shall be of type 2367 // int) or a non-member function with two parameters (the second 2368 // of which shall be of type int), it defines the postfix 2369 // increment operator ++ for objects of that type. 2370 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) { 2371 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1); 2372 bool ParamIsInt = false; 2373 if (const BuiltinType *BT = LastParam->getType()->getAsBuiltinType()) 2374 ParamIsInt = BT->getKind() == BuiltinType::Int; 2375 2376 if (!ParamIsInt) 2377 return Diag(LastParam->getLocation(), 2378 diag::err_operator_overload_post_incdec_must_be_int) 2379 << LastParam->getType() << (Op == OO_MinusMinus); 2380 } 2381 2382 // Notify the class if it got an assignment operator. 2383 if (Op == OO_Equal) { 2384 // Would have returned earlier otherwise. 2385 assert(isa<CXXMethodDecl>(FnDecl) && 2386 "Overloaded = not member, but not filtered."); 2387 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 2388 Method->getParent()->addedAssignmentOperator(Context, Method); 2389 } 2390 2391 return false; 2392} 2393 2394/// ActOnStartLinkageSpecification - Parsed the beginning of a C++ 2395/// linkage specification, including the language and (if present) 2396/// the '{'. ExternLoc is the location of the 'extern', LangLoc is 2397/// the location of the language string literal, which is provided 2398/// by Lang/StrSize. LBraceLoc, if valid, provides the location of 2399/// the '{' brace. Otherwise, this linkage specification does not 2400/// have any braces. 2401Sema::DeclTy *Sema::ActOnStartLinkageSpecification(Scope *S, 2402 SourceLocation ExternLoc, 2403 SourceLocation LangLoc, 2404 const char *Lang, 2405 unsigned StrSize, 2406 SourceLocation LBraceLoc) { 2407 LinkageSpecDecl::LanguageIDs Language; 2408 if (strncmp(Lang, "\"C\"", StrSize) == 0) 2409 Language = LinkageSpecDecl::lang_c; 2410 else if (strncmp(Lang, "\"C++\"", StrSize) == 0) 2411 Language = LinkageSpecDecl::lang_cxx; 2412 else { 2413 Diag(LangLoc, diag::err_bad_language); 2414 return 0; 2415 } 2416 2417 // FIXME: Add all the various semantics of linkage specifications 2418 2419 LinkageSpecDecl *D = LinkageSpecDecl::Create(Context, CurContext, 2420 LangLoc, Language, 2421 LBraceLoc.isValid()); 2422 CurContext->addDecl(D); 2423 PushDeclContext(S, D); 2424 return D; 2425} 2426 2427/// ActOnFinishLinkageSpecification - Completely the definition of 2428/// the C++ linkage specification LinkageSpec. If RBraceLoc is 2429/// valid, it's the position of the closing '}' brace in a linkage 2430/// specification that uses braces. 2431Sema::DeclTy *Sema::ActOnFinishLinkageSpecification(Scope *S, 2432 DeclTy *LinkageSpec, 2433 SourceLocation RBraceLoc) { 2434 if (LinkageSpec) 2435 PopDeclContext(); 2436 return LinkageSpec; 2437} 2438 2439/// ActOnExceptionDeclarator - Parsed the exception-declarator in a C++ catch 2440/// handler. 2441Sema::DeclTy *Sema::ActOnExceptionDeclarator(Scope *S, Declarator &D) 2442{ 2443 QualType ExDeclType = GetTypeForDeclarator(D, S); 2444 SourceLocation Begin = D.getDeclSpec().getSourceRange().getBegin(); 2445 2446 bool Invalid = false; 2447 2448 // Arrays and functions decay. 2449 if (ExDeclType->isArrayType()) 2450 ExDeclType = Context.getArrayDecayedType(ExDeclType); 2451 else if (ExDeclType->isFunctionType()) 2452 ExDeclType = Context.getPointerType(ExDeclType); 2453 2454 // C++ 15.3p1: The exception-declaration shall not denote an incomplete type. 2455 // The exception-declaration shall not denote a pointer or reference to an 2456 // incomplete type, other than [cv] void*. 2457 // N2844 forbids rvalue references. 2458 if(ExDeclType->isRValueReferenceType()) { 2459 Diag(Begin, diag::err_catch_rvalue_ref) << D.getSourceRange(); 2460 Invalid = true; 2461 } 2462 QualType BaseType = ExDeclType; 2463 int Mode = 0; // 0 for direct type, 1 for pointer, 2 for reference 2464 unsigned DK = diag::err_catch_incomplete; 2465 if (const PointerType *Ptr = BaseType->getAsPointerType()) { 2466 BaseType = Ptr->getPointeeType(); 2467 Mode = 1; 2468 DK = diag::err_catch_incomplete_ptr; 2469 } else if(const ReferenceType *Ref = BaseType->getAsReferenceType()) { 2470 // For the purpose of error recovery, we treat rvalue refs like lvalue refs. 2471 BaseType = Ref->getPointeeType(); 2472 Mode = 2; 2473 DK = diag::err_catch_incomplete_ref; 2474 } 2475 if (!Invalid && (Mode == 0 || !BaseType->isVoidType()) && 2476 RequireCompleteType(Begin, BaseType, DK)) 2477 Invalid = true; 2478 2479 // FIXME: Need to test for ability to copy-construct and destroy the 2480 // exception variable. 2481 // FIXME: Need to check for abstract classes. 2482 2483 IdentifierInfo *II = D.getIdentifier(); 2484 if (NamedDecl *PrevDecl = LookupName(S, II, LookupOrdinaryName)) { 2485 // The scope should be freshly made just for us. There is just no way 2486 // it contains any previous declaration. 2487 assert(!S->isDeclScope(PrevDecl)); 2488 if (PrevDecl->isTemplateParameter()) { 2489 // Maybe we will complain about the shadowed template parameter. 2490 DiagnoseTemplateParameterShadow(D.getIdentifierLoc(), PrevDecl); 2491 2492 } 2493 } 2494 2495 VarDecl *ExDecl = VarDecl::Create(Context, CurContext, D.getIdentifierLoc(), 2496 II, ExDeclType, VarDecl::None, Begin); 2497 if (D.getInvalidType() || Invalid) 2498 ExDecl->setInvalidDecl(); 2499 2500 if (D.getCXXScopeSpec().isSet()) { 2501 Diag(D.getIdentifierLoc(), diag::err_qualified_catch_declarator) 2502 << D.getCXXScopeSpec().getRange(); 2503 ExDecl->setInvalidDecl(); 2504 } 2505 2506 // Add the exception declaration into this scope. 2507 S->AddDecl(ExDecl); 2508 if (II) 2509 IdResolver.AddDecl(ExDecl); 2510 2511 ProcessDeclAttributes(ExDecl, D); 2512 return ExDecl; 2513} 2514 2515Sema::DeclTy *Sema::ActOnStaticAssertDeclaration(SourceLocation AssertLoc, 2516 ExprArg assertexpr, 2517 ExprArg assertmessageexpr) { 2518 Expr *AssertExpr = (Expr *)assertexpr.get(); 2519 StringLiteral *AssertMessage = 2520 cast<StringLiteral>((Expr *)assertmessageexpr.get()); 2521 2522 if (!AssertExpr->isTypeDependent() && !AssertExpr->isValueDependent()) { 2523 llvm::APSInt Value(32); 2524 if (!AssertExpr->isIntegerConstantExpr(Value, Context)) { 2525 Diag(AssertLoc, diag::err_static_assert_expression_is_not_constant) << 2526 AssertExpr->getSourceRange(); 2527 return 0; 2528 } 2529 2530 if (Value == 0) { 2531 std::string str(AssertMessage->getStrData(), 2532 AssertMessage->getByteLength()); 2533 Diag(AssertLoc, diag::err_static_assert_failed) 2534 << str << AssertExpr->getSourceRange(); 2535 } 2536 } 2537 2538 assertexpr.release(); 2539 assertmessageexpr.release(); 2540 Decl *Decl = StaticAssertDecl::Create(Context, CurContext, AssertLoc, 2541 AssertExpr, AssertMessage); 2542 2543 CurContext->addDecl(Decl); 2544 return Decl; 2545} 2546 2547void Sema::SetDeclDeleted(DeclTy *dcl, SourceLocation DelLoc) { 2548 Decl *Dcl = static_cast<Decl*>(dcl); 2549 FunctionDecl *Fn = dyn_cast<FunctionDecl>(Dcl); 2550 if (!Fn) { 2551 Diag(DelLoc, diag::err_deleted_non_function); 2552 return; 2553 } 2554 if (const FunctionDecl *Prev = Fn->getPreviousDeclaration()) { 2555 Diag(DelLoc, diag::err_deleted_decl_not_first); 2556 Diag(Prev->getLocation(), diag::note_previous_declaration); 2557 // If the declaration wasn't the first, we delete the function anyway for 2558 // recovery. 2559 } 2560 Fn->setDeleted(); 2561} 2562