SemaDeclCXX.cpp revision 2e1cd4264d363ca869bf37ef160902f211d21b8c
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/TypeOrdering.h" 19#include "clang/AST/StmtVisitor.h" 20#include "clang/Lex/Preprocessor.h" 21#include "clang/Basic/Diagnostic.h" 22#include "clang/Parse/DeclSpec.h" 23#include "llvm/Support/Compiler.h" 24#include <algorithm> // for std::equal 25#include <map> 26 27using namespace clang; 28 29//===----------------------------------------------------------------------===// 30// CheckDefaultArgumentVisitor 31//===----------------------------------------------------------------------===// 32 33namespace { 34 /// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses 35 /// the default argument of a parameter to determine whether it 36 /// contains any ill-formed subexpressions. For example, this will 37 /// diagnose the use of local variables or parameters within the 38 /// default argument expression. 39 class VISIBILITY_HIDDEN CheckDefaultArgumentVisitor 40 : public StmtVisitor<CheckDefaultArgumentVisitor, bool> { 41 Expr *DefaultArg; 42 Sema *S; 43 44 public: 45 CheckDefaultArgumentVisitor(Expr *defarg, Sema *s) 46 : DefaultArg(defarg), S(s) {} 47 48 bool VisitExpr(Expr *Node); 49 bool VisitDeclRefExpr(DeclRefExpr *DRE); 50 bool VisitCXXThisExpr(CXXThisExpr *ThisE); 51 }; 52 53 /// VisitExpr - Visit all of the children of this expression. 54 bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) { 55 bool IsInvalid = false; 56 for (Stmt::child_iterator I = Node->child_begin(), 57 E = Node->child_end(); I != E; ++I) 58 IsInvalid |= Visit(*I); 59 return IsInvalid; 60 } 61 62 /// VisitDeclRefExpr - Visit a reference to a declaration, to 63 /// determine whether this declaration can be used in the default 64 /// argument expression. 65 bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) { 66 NamedDecl *Decl = DRE->getDecl(); 67 if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) { 68 // C++ [dcl.fct.default]p9 69 // Default arguments are evaluated each time the function is 70 // called. The order of evaluation of function arguments is 71 // unspecified. Consequently, parameters of a function shall not 72 // be used in default argument expressions, even if they are not 73 // evaluated. Parameters of a function declared before a default 74 // argument expression are in scope and can hide namespace and 75 // class member names. 76 return S->Diag(DRE->getSourceRange().getBegin(), 77 diag::err_param_default_argument_references_param, 78 Param->getName(), DefaultArg->getSourceRange()); 79 } else if (VarDecl *VDecl = dyn_cast<VarDecl>(Decl)) { 80 // C++ [dcl.fct.default]p7 81 // Local variables shall not be used in default argument 82 // expressions. 83 if (VDecl->isBlockVarDecl()) 84 return S->Diag(DRE->getSourceRange().getBegin(), 85 diag::err_param_default_argument_references_local, 86 VDecl->getName(), DefaultArg->getSourceRange()); 87 } 88 89 return false; 90 } 91 92 /// VisitCXXThisExpr - Visit a C++ "this" expression. 93 bool CheckDefaultArgumentVisitor::VisitCXXThisExpr(CXXThisExpr *ThisE) { 94 // C++ [dcl.fct.default]p8: 95 // The keyword this shall not be used in a default argument of a 96 // member function. 97 return S->Diag(ThisE->getSourceRange().getBegin(), 98 diag::err_param_default_argument_references_this, 99 ThisE->getSourceRange()); 100 } 101} 102 103/// ActOnParamDefaultArgument - Check whether the default argument 104/// provided for a function parameter is well-formed. If so, attach it 105/// to the parameter declaration. 106void 107Sema::ActOnParamDefaultArgument(DeclTy *param, SourceLocation EqualLoc, 108 ExprTy *defarg) { 109 ParmVarDecl *Param = (ParmVarDecl *)param; 110 llvm::OwningPtr<Expr> DefaultArg((Expr *)defarg); 111 QualType ParamType = Param->getType(); 112 113 // Default arguments are only permitted in C++ 114 if (!getLangOptions().CPlusPlus) { 115 Diag(EqualLoc, diag::err_param_default_argument, 116 DefaultArg->getSourceRange()); 117 return; 118 } 119 120 // C++ [dcl.fct.default]p5 121 // A default argument expression is implicitly converted (clause 122 // 4) to the parameter type. The default argument expression has 123 // the same semantic constraints as the initializer expression in 124 // a declaration of a variable of the parameter type, using the 125 // copy-initialization semantics (8.5). 126 Expr *DefaultArgPtr = DefaultArg.get(); 127 bool DefaultInitFailed = PerformCopyInitialization(DefaultArgPtr, ParamType, 128 "in default argument"); 129 if (DefaultArgPtr != DefaultArg.get()) { 130 DefaultArg.take(); 131 DefaultArg.reset(DefaultArgPtr); 132 } 133 if (DefaultInitFailed) { 134 return; 135 } 136 137 // Check that the default argument is well-formed 138 CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg.get(), this); 139 if (DefaultArgChecker.Visit(DefaultArg.get())) 140 return; 141 142 // Okay: add the default argument to the parameter 143 Param->setDefaultArg(DefaultArg.take()); 144} 145 146/// CheckExtraCXXDefaultArguments - Check for any extra default 147/// arguments in the declarator, which is not a function declaration 148/// or definition and therefore is not permitted to have default 149/// arguments. This routine should be invoked for every declarator 150/// that is not a function declaration or definition. 151void Sema::CheckExtraCXXDefaultArguments(Declarator &D) { 152 // C++ [dcl.fct.default]p3 153 // A default argument expression shall be specified only in the 154 // parameter-declaration-clause of a function declaration or in a 155 // template-parameter (14.1). It shall not be specified for a 156 // parameter pack. If it is specified in a 157 // parameter-declaration-clause, it shall not occur within a 158 // declarator or abstract-declarator of a parameter-declaration. 159 for (unsigned i = 0; i < D.getNumTypeObjects(); ++i) { 160 DeclaratorChunk &chunk = D.getTypeObject(i); 161 if (chunk.Kind == DeclaratorChunk::Function) { 162 for (unsigned argIdx = 0; argIdx < chunk.Fun.NumArgs; ++argIdx) { 163 ParmVarDecl *Param = (ParmVarDecl *)chunk.Fun.ArgInfo[argIdx].Param; 164 if (Param->getDefaultArg()) { 165 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc, 166 Param->getDefaultArg()->getSourceRange()); 167 Param->setDefaultArg(0); 168 } 169 } 170 } 171 } 172} 173 174// MergeCXXFunctionDecl - Merge two declarations of the same C++ 175// function, once we already know that they have the same 176// type. Subroutine of MergeFunctionDecl. 177FunctionDecl * 178Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old) { 179 // C++ [dcl.fct.default]p4: 180 // 181 // For non-template functions, default arguments can be added in 182 // later declarations of a function in the same 183 // scope. Declarations in different scopes have completely 184 // distinct sets of default arguments. That is, declarations in 185 // inner scopes do not acquire default arguments from 186 // declarations in outer scopes, and vice versa. In a given 187 // function declaration, all parameters subsequent to a 188 // parameter with a default argument shall have default 189 // arguments supplied in this or previous declarations. A 190 // default argument shall not be redefined by a later 191 // declaration (not even to the same value). 192 for (unsigned p = 0, NumParams = Old->getNumParams(); p < NumParams; ++p) { 193 ParmVarDecl *OldParam = Old->getParamDecl(p); 194 ParmVarDecl *NewParam = New->getParamDecl(p); 195 196 if(OldParam->getDefaultArg() && NewParam->getDefaultArg()) { 197 Diag(NewParam->getLocation(), 198 diag::err_param_default_argument_redefinition, 199 NewParam->getDefaultArg()->getSourceRange()); 200 Diag(OldParam->getLocation(), diag::err_previous_definition); 201 } else if (OldParam->getDefaultArg()) { 202 // Merge the old default argument into the new parameter 203 NewParam->setDefaultArg(OldParam->getDefaultArg()); 204 } 205 } 206 207 return New; 208} 209 210/// CheckCXXDefaultArguments - Verify that the default arguments for a 211/// function declaration are well-formed according to C++ 212/// [dcl.fct.default]. 213void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) { 214 unsigned NumParams = FD->getNumParams(); 215 unsigned p; 216 217 // Find first parameter with a default argument 218 for (p = 0; p < NumParams; ++p) { 219 ParmVarDecl *Param = FD->getParamDecl(p); 220 if (Param->getDefaultArg()) 221 break; 222 } 223 224 // C++ [dcl.fct.default]p4: 225 // In a given function declaration, all parameters 226 // subsequent to a parameter with a default argument shall 227 // have default arguments supplied in this or previous 228 // declarations. A default argument shall not be redefined 229 // by a later declaration (not even to the same value). 230 unsigned LastMissingDefaultArg = 0; 231 for(; p < NumParams; ++p) { 232 ParmVarDecl *Param = FD->getParamDecl(p); 233 if (!Param->getDefaultArg()) { 234 if (Param->getIdentifier()) 235 Diag(Param->getLocation(), 236 diag::err_param_default_argument_missing_name, 237 Param->getIdentifier()->getName()); 238 else 239 Diag(Param->getLocation(), 240 diag::err_param_default_argument_missing); 241 242 LastMissingDefaultArg = p; 243 } 244 } 245 246 if (LastMissingDefaultArg > 0) { 247 // Some default arguments were missing. Clear out all of the 248 // default arguments up to (and including) the last missing 249 // default argument, so that we leave the function parameters 250 // in a semantically valid state. 251 for (p = 0; p <= LastMissingDefaultArg; ++p) { 252 ParmVarDecl *Param = FD->getParamDecl(p); 253 if (Param->getDefaultArg()) { 254 delete Param->getDefaultArg(); 255 Param->setDefaultArg(0); 256 } 257 } 258 } 259} 260 261/// isCurrentClassName - Determine whether the identifier II is the 262/// name of the class type currently being defined. In the case of 263/// nested classes, this will only return true if II is the name of 264/// the innermost class. 265bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *, 266 const CXXScopeSpec *SS) { 267 CXXRecordDecl *CurDecl; 268 if (SS) { 269 DeclContext *DC = static_cast<DeclContext*>(SS->getScopeRep()); 270 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC); 271 } else 272 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 273 274 if (CurDecl) 275 return &II == CurDecl->getIdentifier(); 276 else 277 return false; 278} 279 280/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is 281/// one entry in the base class list of a class specifier, for 282/// example: 283/// class foo : public bar, virtual private baz { 284/// 'public bar' and 'virtual private baz' are each base-specifiers. 285Sema::BaseResult 286Sema::ActOnBaseSpecifier(DeclTy *classdecl, SourceRange SpecifierRange, 287 bool Virtual, AccessSpecifier Access, 288 TypeTy *basetype, SourceLocation BaseLoc) { 289 RecordDecl *Decl = (RecordDecl*)classdecl; 290 QualType BaseType = Context.getTypeDeclType((TypeDecl*)basetype); 291 292 // Base specifiers must be record types. 293 if (!BaseType->isRecordType()) { 294 Diag(BaseLoc, diag::err_base_must_be_class, SpecifierRange); 295 return true; 296 } 297 298 // C++ [class.union]p1: 299 // A union shall not be used as a base class. 300 if (BaseType->isUnionType()) { 301 Diag(BaseLoc, diag::err_union_as_base_class, SpecifierRange); 302 return true; 303 } 304 305 // C++ [class.union]p1: 306 // A union shall not have base classes. 307 if (Decl->isUnion()) { 308 Diag(Decl->getLocation(), diag::err_base_clause_on_union, 309 SpecifierRange); 310 return true; 311 } 312 313 // C++ [class.derived]p2: 314 // The class-name in a base-specifier shall not be an incompletely 315 // defined class. 316 if (BaseType->isIncompleteType()) { 317 Diag(BaseLoc, diag::err_incomplete_base_class, SpecifierRange); 318 return true; 319 } 320 321 // If the base class is polymorphic, the new one is, too. 322 RecordDecl *BaseDecl = BaseType->getAsRecordType()->getDecl(); 323 assert(BaseDecl && "Record type has no declaration"); 324 BaseDecl = BaseDecl->getDefinition(Context); 325 assert(BaseDecl && "Base type is not incomplete, but has no definition"); 326 if (cast<CXXRecordDecl>(BaseDecl)->isPolymorphic()) { 327 cast<CXXRecordDecl>(Decl)->setPolymorphic(true); 328 } 329 330 // Create the base specifier. 331 return new CXXBaseSpecifier(SpecifierRange, Virtual, 332 BaseType->isClassType(), Access, BaseType); 333} 334 335/// ActOnBaseSpecifiers - Attach the given base specifiers to the 336/// class, after checking whether there are any duplicate base 337/// classes. 338void Sema::ActOnBaseSpecifiers(DeclTy *ClassDecl, BaseTy **Bases, 339 unsigned NumBases) { 340 if (NumBases == 0) 341 return; 342 343 // Used to keep track of which base types we have already seen, so 344 // that we can properly diagnose redundant direct base types. Note 345 // that the key is always the unqualified canonical type of the base 346 // class. 347 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes; 348 349 // Copy non-redundant base specifiers into permanent storage. 350 CXXBaseSpecifier **BaseSpecs = (CXXBaseSpecifier **)Bases; 351 unsigned NumGoodBases = 0; 352 for (unsigned idx = 0; idx < NumBases; ++idx) { 353 QualType NewBaseType 354 = Context.getCanonicalType(BaseSpecs[idx]->getType()); 355 NewBaseType = NewBaseType.getUnqualifiedType(); 356 357 if (KnownBaseTypes[NewBaseType]) { 358 // C++ [class.mi]p3: 359 // A class shall not be specified as a direct base class of a 360 // derived class more than once. 361 Diag(BaseSpecs[idx]->getSourceRange().getBegin(), 362 diag::err_duplicate_base_class, 363 KnownBaseTypes[NewBaseType]->getType().getAsString(), 364 BaseSpecs[idx]->getSourceRange()); 365 366 // Delete the duplicate base class specifier; we're going to 367 // overwrite its pointer later. 368 delete BaseSpecs[idx]; 369 } else { 370 // Okay, add this new base class. 371 KnownBaseTypes[NewBaseType] = BaseSpecs[idx]; 372 BaseSpecs[NumGoodBases++] = BaseSpecs[idx]; 373 } 374 } 375 376 // Attach the remaining base class specifiers to the derived class. 377 CXXRecordDecl *Decl = (CXXRecordDecl*)ClassDecl; 378 Decl->setBases(BaseSpecs, NumGoodBases); 379 380 // Delete the remaining (good) base class specifiers, since their 381 // data has been copied into the CXXRecordDecl. 382 for (unsigned idx = 0; idx < NumGoodBases; ++idx) 383 delete BaseSpecs[idx]; 384} 385 386//===----------------------------------------------------------------------===// 387// C++ class member Handling 388//===----------------------------------------------------------------------===// 389 390/// ActOnStartCXXClassDef - This is called at the start of a class/struct/union 391/// definition, when on C++. 392void Sema::ActOnStartCXXClassDef(Scope *S, DeclTy *D, SourceLocation LBrace) { 393 CXXRecordDecl *Dcl = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 394 PushDeclContext(Dcl); 395 FieldCollector->StartClass(); 396 397 if (Dcl->getIdentifier()) { 398 // C++ [class]p2: 399 // [...] The class-name is also inserted into the scope of the 400 // class itself; this is known as the injected-class-name. For 401 // purposes of access checking, the injected-class-name is treated 402 // as if it were a public member name. 403 PushOnScopeChains(Dcl, S); 404 } 405} 406 407/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member 408/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the 409/// bitfield width if there is one and 'InitExpr' specifies the initializer if 410/// any. 'LastInGroup' is non-null for cases where one declspec has multiple 411/// declarators on it. 412/// 413/// NOTE: Because of CXXFieldDecl's inability to be chained like ScopedDecls, if 414/// an instance field is declared, a new CXXFieldDecl is created but the method 415/// does *not* return it; it returns LastInGroup instead. The other C++ members 416/// (which are all ScopedDecls) are returned after appending them to 417/// LastInGroup. 418Sema::DeclTy * 419Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D, 420 ExprTy *BW, ExprTy *InitExpr, 421 DeclTy *LastInGroup) { 422 const DeclSpec &DS = D.getDeclSpec(); 423 IdentifierInfo *II = D.getIdentifier(); 424 Expr *BitWidth = static_cast<Expr*>(BW); 425 Expr *Init = static_cast<Expr*>(InitExpr); 426 SourceLocation Loc = D.getIdentifierLoc(); 427 428 bool isFunc = D.isFunctionDeclarator(); 429 430 // C++ 9.2p6: A member shall not be declared to have automatic storage 431 // duration (auto, register) or with the extern storage-class-specifier. 432 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class 433 // data members and cannot be applied to names declared const or static, 434 // and cannot be applied to reference members. 435 switch (DS.getStorageClassSpec()) { 436 case DeclSpec::SCS_unspecified: 437 case DeclSpec::SCS_typedef: 438 case DeclSpec::SCS_static: 439 // FALL THROUGH. 440 break; 441 case DeclSpec::SCS_mutable: 442 if (isFunc) { 443 if (DS.getStorageClassSpecLoc().isValid()) 444 Diag(DS.getStorageClassSpecLoc(), 445 diag::err_mutable_function); 446 else 447 Diag(DS.getThreadSpecLoc(), 448 diag::err_mutable_function); 449 D.getMutableDeclSpec().ClearStorageClassSpecs(); 450 } else { 451 QualType T = GetTypeForDeclarator(D, S); 452 diag::kind err = static_cast<diag::kind>(0); 453 if (T->isReferenceType()) 454 err = diag::err_mutable_reference; 455 else if (T.isConstQualified()) 456 err = diag::err_mutable_const; 457 if (err != 0) { 458 if (DS.getStorageClassSpecLoc().isValid()) 459 Diag(DS.getStorageClassSpecLoc(), err); 460 else 461 Diag(DS.getThreadSpecLoc(), err); 462 D.getMutableDeclSpec().ClearStorageClassSpecs(); 463 } 464 } 465 break; 466 default: 467 if (DS.getStorageClassSpecLoc().isValid()) 468 Diag(DS.getStorageClassSpecLoc(), 469 diag::err_storageclass_invalid_for_member); 470 else 471 Diag(DS.getThreadSpecLoc(), diag::err_storageclass_invalid_for_member); 472 D.getMutableDeclSpec().ClearStorageClassSpecs(); 473 } 474 475 if (!isFunc && 476 D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_typedef && 477 D.getNumTypeObjects() == 0) { 478 // Check also for this case: 479 // 480 // typedef int f(); 481 // f a; 482 // 483 Decl *TD = static_cast<Decl *>(DS.getTypeRep()); 484 isFunc = Context.getTypeDeclType(cast<TypeDecl>(TD))->isFunctionType(); 485 } 486 487 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified || 488 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) && 489 !isFunc); 490 491 Decl *Member; 492 bool InvalidDecl = false; 493 494 if (isInstField) 495 Member = static_cast<Decl*>(ActOnField(S, Loc, D, BitWidth)); 496 else 497 Member = static_cast<Decl*>(ActOnDeclarator(S, D, LastInGroup)); 498 499 if (!Member) return LastInGroup; 500 501 assert((II || isInstField) && "No identifier for non-field ?"); 502 503 // set/getAccess is not part of Decl's interface to avoid bloating it with C++ 504 // specific methods. Use a wrapper class that can be used with all C++ class 505 // member decls. 506 CXXClassMemberWrapper(Member).setAccess(AS); 507 508 // C++ [dcl.init.aggr]p1: 509 // An aggregate is an array or a class (clause 9) with [...] no 510 // private or protected non-static data members (clause 11). 511 if (isInstField && (AS == AS_private || AS == AS_protected)) 512 cast<CXXRecordDecl>(CurContext)->setAggregate(false); 513 514 if (DS.isVirtualSpecified()) { 515 if (!isFunc || DS.getStorageClassSpec() == DeclSpec::SCS_static) { 516 Diag(DS.getVirtualSpecLoc(), diag::err_virtual_non_function); 517 InvalidDecl = true; 518 } else { 519 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(CurContext); 520 CurClass->setAggregate(false); 521 CurClass->setPolymorphic(true); 522 } 523 } 524 525 if (BitWidth) { 526 // C++ 9.6p2: Only when declaring an unnamed bit-field may the 527 // constant-expression be a value equal to zero. 528 // FIXME: Check this. 529 530 if (D.isFunctionDeclarator()) { 531 // FIXME: Emit diagnostic about only constructors taking base initializers 532 // or something similar, when constructor support is in place. 533 Diag(Loc, diag::err_not_bitfield_type, 534 II->getName(), BitWidth->getSourceRange()); 535 InvalidDecl = true; 536 537 } else if (isInstField) { 538 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 539 if (!cast<FieldDecl>(Member)->getType()->isIntegralType()) { 540 Diag(Loc, diag::err_not_integral_type_bitfield, 541 II->getName(), BitWidth->getSourceRange()); 542 InvalidDecl = true; 543 } 544 545 } else if (isa<FunctionDecl>(Member)) { 546 // A function typedef ("typedef int f(); f a;"). 547 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 548 Diag(Loc, diag::err_not_integral_type_bitfield, 549 II->getName(), BitWidth->getSourceRange()); 550 InvalidDecl = true; 551 552 } else if (isa<TypedefDecl>(Member)) { 553 // "cannot declare 'A' to be a bit-field type" 554 Diag(Loc, diag::err_not_bitfield_type, II->getName(), 555 BitWidth->getSourceRange()); 556 InvalidDecl = true; 557 558 } else { 559 assert(isa<CXXClassVarDecl>(Member) && 560 "Didn't we cover all member kinds?"); 561 // C++ 9.6p3: A bit-field shall not be a static member. 562 // "static member 'A' cannot be a bit-field" 563 Diag(Loc, diag::err_static_not_bitfield, II->getName(), 564 BitWidth->getSourceRange()); 565 InvalidDecl = true; 566 } 567 } 568 569 if (Init) { 570 // C++ 9.2p4: A member-declarator can contain a constant-initializer only 571 // if it declares a static member of const integral or const enumeration 572 // type. 573 if (CXXClassVarDecl *CVD = dyn_cast<CXXClassVarDecl>(Member)) { 574 // ...static member of... 575 CVD->setInit(Init); 576 // ...const integral or const enumeration type. 577 if (Context.getCanonicalType(CVD->getType()).isConstQualified() && 578 CVD->getType()->isIntegralType()) { 579 // constant-initializer 580 if (CheckForConstantInitializer(Init, CVD->getType())) 581 InvalidDecl = true; 582 583 } else { 584 // not const integral. 585 Diag(Loc, diag::err_member_initialization, 586 II->getName(), Init->getSourceRange()); 587 InvalidDecl = true; 588 } 589 590 } else { 591 // not static member. 592 Diag(Loc, diag::err_member_initialization, 593 II->getName(), Init->getSourceRange()); 594 InvalidDecl = true; 595 } 596 } 597 598 if (InvalidDecl) 599 Member->setInvalidDecl(); 600 601 if (isInstField) { 602 FieldCollector->Add(cast<CXXFieldDecl>(Member)); 603 return LastInGroup; 604 } 605 return Member; 606} 607 608/// ActOnMemInitializer - Handle a C++ member initializer. 609Sema::MemInitResult 610Sema::ActOnMemInitializer(DeclTy *ConstructorD, 611 Scope *S, 612 IdentifierInfo *MemberOrBase, 613 SourceLocation IdLoc, 614 SourceLocation LParenLoc, 615 ExprTy **Args, unsigned NumArgs, 616 SourceLocation *CommaLocs, 617 SourceLocation RParenLoc) { 618 CXXConstructorDecl *Constructor 619 = dyn_cast<CXXConstructorDecl>((Decl*)ConstructorD); 620 if (!Constructor) { 621 // The user wrote a constructor initializer on a function that is 622 // not a C++ constructor. Ignore the error for now, because we may 623 // have more member initializers coming; we'll diagnose it just 624 // once in ActOnMemInitializers. 625 return true; 626 } 627 628 CXXRecordDecl *ClassDecl = Constructor->getParent(); 629 630 // C++ [class.base.init]p2: 631 // Names in a mem-initializer-id are looked up in the scope of the 632 // constructor’s class and, if not found in that scope, are looked 633 // up in the scope containing the constructor’s 634 // definition. [Note: if the constructor’s class contains a member 635 // with the same name as a direct or virtual base class of the 636 // class, a mem-initializer-id naming the member or base class and 637 // composed of a single identifier refers to the class member. A 638 // mem-initializer-id for the hidden base class may be specified 639 // using a qualified name. ] 640 // Look for a member, first. 641 CXXFieldDecl *Member = ClassDecl->getMember(MemberOrBase); 642 643 // FIXME: Handle members of an anonymous union. 644 645 if (Member) { 646 // FIXME: Perform direct initialization of the member. 647 return new CXXBaseOrMemberInitializer(Member, (Expr **)Args, NumArgs); 648 } 649 650 // It didn't name a member, so see if it names a class. 651 TypeTy *BaseTy = isTypeName(*MemberOrBase, S, 0/*SS*/); 652 if (!BaseTy) 653 return Diag(IdLoc, diag::err_mem_init_not_member_or_class, 654 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 655 656 QualType BaseType = Context.getTypeDeclType((TypeDecl *)BaseTy); 657 if (!BaseType->isRecordType()) 658 return Diag(IdLoc, diag::err_base_init_does_not_name_class, 659 BaseType.getAsString(), SourceRange(IdLoc, RParenLoc)); 660 661 // C++ [class.base.init]p2: 662 // [...] Unless the mem-initializer-id names a nonstatic data 663 // member of the constructor’s class or a direct or virtual base 664 // of that class, the mem-initializer is ill-formed. A 665 // mem-initializer-list can initialize a base class using any 666 // name that denotes that base class type. 667 668 // First, check for a direct base class. 669 const CXXBaseSpecifier *DirectBaseSpec = 0; 670 for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin(); 671 Base != ClassDecl->bases_end(); ++Base) { 672 if (Context.getCanonicalType(BaseType).getUnqualifiedType() == 673 Context.getCanonicalType(Base->getType()).getUnqualifiedType()) { 674 // We found a direct base of this type. That's what we're 675 // initializing. 676 DirectBaseSpec = &*Base; 677 break; 678 } 679 } 680 681 // Check for a virtual base class. 682 // FIXME: We might be able to short-circuit this if we know in 683 // advance that there are no virtual bases. 684 const CXXBaseSpecifier *VirtualBaseSpec = 0; 685 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) { 686 // We haven't found a base yet; search the class hierarchy for a 687 // virtual base class. 688 BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 689 /*DetectVirtual=*/false); 690 if (IsDerivedFrom(Context.getTypeDeclType(ClassDecl), BaseType, Paths)) { 691 for (BasePaths::paths_iterator Path = Paths.begin(); 692 Path != Paths.end(); ++Path) { 693 if (Path->back().Base->isVirtual()) { 694 VirtualBaseSpec = Path->back().Base; 695 break; 696 } 697 } 698 } 699 } 700 701 // C++ [base.class.init]p2: 702 // If a mem-initializer-id is ambiguous because it designates both 703 // a direct non-virtual base class and an inherited virtual base 704 // class, the mem-initializer is ill-formed. 705 if (DirectBaseSpec && VirtualBaseSpec) 706 return Diag(IdLoc, diag::err_base_init_direct_and_virtual, 707 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 708 709 return new CXXBaseOrMemberInitializer(BaseType, (Expr **)Args, NumArgs); 710} 711 712 713void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc, 714 DeclTy *TagDecl, 715 SourceLocation LBrac, 716 SourceLocation RBrac) { 717 ActOnFields(S, RLoc, TagDecl, 718 (DeclTy**)FieldCollector->getCurFields(), 719 FieldCollector->getCurNumFields(), LBrac, RBrac, 0); 720} 721 722/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared 723/// special functions, such as the default constructor, copy 724/// constructor, or destructor, to the given C++ class (C++ 725/// [special]p1). This routine can only be executed just before the 726/// definition of the class is complete. 727void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) { 728 QualType ClassType = Context.getTypeDeclType(ClassDecl); 729 ClassType = Context.getCanonicalType(ClassType); 730 731 if (!ClassDecl->hasUserDeclaredConstructor()) { 732 // C++ [class.ctor]p5: 733 // A default constructor for a class X is a constructor of class X 734 // that can be called without an argument. If there is no 735 // user-declared constructor for class X, a default constructor is 736 // implicitly declared. An implicitly-declared default constructor 737 // is an inline public member of its class. 738 DeclarationName Name 739 = Context.DeclarationNames.getCXXConstructorName(ClassType); 740 CXXConstructorDecl *DefaultCon = 741 CXXConstructorDecl::Create(Context, ClassDecl, 742 ClassDecl->getLocation(), Name, 743 Context.getFunctionType(Context.VoidTy, 744 0, 0, false, 0), 745 /*isExplicit=*/false, 746 /*isInline=*/true, 747 /*isImplicitlyDeclared=*/true); 748 DefaultCon->setAccess(AS_public); 749 ClassDecl->addConstructor(Context, DefaultCon); 750 } 751 752 if (!ClassDecl->hasUserDeclaredCopyConstructor()) { 753 // C++ [class.copy]p4: 754 // If the class definition does not explicitly declare a copy 755 // constructor, one is declared implicitly. 756 757 // C++ [class.copy]p5: 758 // The implicitly-declared copy constructor for a class X will 759 // have the form 760 // 761 // X::X(const X&) 762 // 763 // if 764 bool HasConstCopyConstructor = true; 765 766 // -- each direct or virtual base class B of X has a copy 767 // constructor whose first parameter is of type const B& or 768 // const volatile B&, and 769 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 770 HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { 771 const CXXRecordDecl *BaseClassDecl 772 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 773 HasConstCopyConstructor 774 = BaseClassDecl->hasConstCopyConstructor(Context); 775 } 776 777 // -- for all the nonstatic data members of X that are of a 778 // class type M (or array thereof), each such class type 779 // has a copy constructor whose first parameter is of type 780 // const M& or const volatile M&. 781 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(); 782 HasConstCopyConstructor && Field != ClassDecl->field_end(); ++Field) { 783 QualType FieldType = (*Field)->getType(); 784 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 785 FieldType = Array->getElementType(); 786 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 787 const CXXRecordDecl *FieldClassDecl 788 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 789 HasConstCopyConstructor 790 = FieldClassDecl->hasConstCopyConstructor(Context); 791 } 792 } 793 794 // Otherwise, the implicitly declared copy constructor will have 795 // the form 796 // 797 // X::X(X&) 798 QualType ArgType = Context.getTypeDeclType(ClassDecl); 799 if (HasConstCopyConstructor) 800 ArgType = ArgType.withConst(); 801 ArgType = Context.getReferenceType(ArgType); 802 803 // An implicitly-declared copy constructor is an inline public 804 // member of its class. 805 DeclarationName Name 806 = Context.DeclarationNames.getCXXConstructorName(ClassType); 807 CXXConstructorDecl *CopyConstructor 808 = CXXConstructorDecl::Create(Context, ClassDecl, 809 ClassDecl->getLocation(), Name, 810 Context.getFunctionType(Context.VoidTy, 811 &ArgType, 1, 812 false, 0), 813 /*isExplicit=*/false, 814 /*isInline=*/true, 815 /*isImplicitlyDeclared=*/true); 816 CopyConstructor->setAccess(AS_public); 817 818 // Add the parameter to the constructor. 819 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, 820 ClassDecl->getLocation(), 821 /*IdentifierInfo=*/0, 822 ArgType, VarDecl::None, 0, 0); 823 CopyConstructor->setParams(&FromParam, 1); 824 825 ClassDecl->addConstructor(Context, CopyConstructor); 826 } 827 828 if (!ClassDecl->getDestructor()) { 829 // C++ [class.dtor]p2: 830 // If a class has no user-declared destructor, a destructor is 831 // declared implicitly. An implicitly-declared destructor is an 832 // inline public member of its class. 833 DeclarationName Name 834 = Context.DeclarationNames.getCXXDestructorName(ClassType); 835 CXXDestructorDecl *Destructor 836 = CXXDestructorDecl::Create(Context, ClassDecl, 837 ClassDecl->getLocation(), Name, 838 Context.getFunctionType(Context.VoidTy, 839 0, 0, false, 0), 840 /*isInline=*/true, 841 /*isImplicitlyDeclared=*/true); 842 Destructor->setAccess(AS_public); 843 ClassDecl->setDestructor(Destructor); 844 } 845 846 // FIXME: Implicit copy assignment operator 847} 848 849void Sema::ActOnFinishCXXClassDef(DeclTy *D) { 850 CXXRecordDecl *Rec = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 851 FieldCollector->FinishClass(); 852 AddImplicitlyDeclaredMembersToClass(Rec); 853 PopDeclContext(); 854 855 // Everything, including inline method definitions, have been parsed. 856 // Let the consumer know of the new TagDecl definition. 857 Consumer.HandleTagDeclDefinition(Rec); 858} 859 860/// CheckConstructorDeclarator - Called by ActOnDeclarator to check 861/// the well-formednes of the constructor declarator @p D with type @p 862/// R. If there are any errors in the declarator, this routine will 863/// emit diagnostics and return true. Otherwise, it will return 864/// false. Either way, the type @p R will be updated to reflect a 865/// well-formed type for the constructor. 866bool Sema::CheckConstructorDeclarator(Declarator &D, QualType &R, 867 FunctionDecl::StorageClass& SC) { 868 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 869 bool isInvalid = false; 870 871 // C++ [class.ctor]p3: 872 // A constructor shall not be virtual (10.3) or static (9.4). A 873 // constructor can be invoked for a const, volatile or const 874 // volatile object. A constructor shall not be declared const, 875 // volatile, or const volatile (9.3.2). 876 if (isVirtual) { 877 Diag(D.getIdentifierLoc(), 878 diag::err_constructor_cannot_be, 879 "virtual", 880 SourceRange(D.getDeclSpec().getVirtualSpecLoc()), 881 SourceRange(D.getIdentifierLoc())); 882 isInvalid = true; 883 } 884 if (SC == FunctionDecl::Static) { 885 Diag(D.getIdentifierLoc(), 886 diag::err_constructor_cannot_be, 887 "static", 888 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 889 SourceRange(D.getIdentifierLoc())); 890 isInvalid = true; 891 SC = FunctionDecl::None; 892 } 893 if (D.getDeclSpec().hasTypeSpecifier()) { 894 // Constructors don't have return types, but the parser will 895 // happily parse something like: 896 // 897 // class X { 898 // float X(float); 899 // }; 900 // 901 // The return type will be eliminated later. 902 Diag(D.getIdentifierLoc(), 903 diag::err_constructor_return_type, 904 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 905 SourceRange(D.getIdentifierLoc())); 906 } 907 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 908 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 909 if (FTI.TypeQuals & QualType::Const) 910 Diag(D.getIdentifierLoc(), 911 diag::err_invalid_qualified_constructor, 912 "const", 913 SourceRange(D.getIdentifierLoc())); 914 if (FTI.TypeQuals & QualType::Volatile) 915 Diag(D.getIdentifierLoc(), 916 diag::err_invalid_qualified_constructor, 917 "volatile", 918 SourceRange(D.getIdentifierLoc())); 919 if (FTI.TypeQuals & QualType::Restrict) 920 Diag(D.getIdentifierLoc(), 921 diag::err_invalid_qualified_constructor, 922 "restrict", 923 SourceRange(D.getIdentifierLoc())); 924 } 925 926 // Rebuild the function type "R" without any type qualifiers (in 927 // case any of the errors above fired) and with "void" as the 928 // return type, since constructors don't have return types. We 929 // *always* have to do this, because GetTypeForDeclarator will 930 // put in a result type of "int" when none was specified. 931 const FunctionTypeProto *Proto = R->getAsFunctionTypeProto(); 932 R = Context.getFunctionType(Context.VoidTy, Proto->arg_type_begin(), 933 Proto->getNumArgs(), 934 Proto->isVariadic(), 935 0); 936 937 return isInvalid; 938} 939 940/// CheckDestructorDeclarator - Called by ActOnDeclarator to check 941/// the well-formednes of the destructor declarator @p D with type @p 942/// R. If there are any errors in the declarator, this routine will 943/// emit diagnostics and return true. Otherwise, it will return 944/// false. Either way, the type @p R will be updated to reflect a 945/// well-formed type for the destructor. 946bool Sema::CheckDestructorDeclarator(Declarator &D, QualType &R, 947 FunctionDecl::StorageClass& SC) { 948 bool isInvalid = false; 949 950 // C++ [class.dtor]p1: 951 // [...] A typedef-name that names a class is a class-name 952 // (7.1.3); however, a typedef-name that names a class shall not 953 // be used as the identifier in the declarator for a destructor 954 // declaration. 955 TypeDecl *DeclaratorTypeD = (TypeDecl *)D.getDeclaratorIdType(); 956 if (const TypedefDecl *TypedefD = dyn_cast<TypedefDecl>(DeclaratorTypeD)) { 957 Diag(D.getIdentifierLoc(), 958 diag::err_destructor_typedef_name, 959 TypedefD->getName()); 960 isInvalid = true; 961 } 962 963 // C++ [class.dtor]p2: 964 // A destructor is used to destroy objects of its class type. A 965 // destructor takes no parameters, and no return type can be 966 // specified for it (not even void). The address of a destructor 967 // shall not be taken. A destructor shall not be static. A 968 // destructor can be invoked for a const, volatile or const 969 // volatile object. A destructor shall not be declared const, 970 // volatile or const volatile (9.3.2). 971 if (SC == FunctionDecl::Static) { 972 Diag(D.getIdentifierLoc(), 973 diag::err_destructor_cannot_be, 974 "static", 975 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 976 SourceRange(D.getIdentifierLoc())); 977 isInvalid = true; 978 SC = FunctionDecl::None; 979 } 980 if (D.getDeclSpec().hasTypeSpecifier()) { 981 // Destructors don't have return types, but the parser will 982 // happily parse something like: 983 // 984 // class X { 985 // float ~X(); 986 // }; 987 // 988 // The return type will be eliminated later. 989 Diag(D.getIdentifierLoc(), 990 diag::err_destructor_return_type, 991 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 992 SourceRange(D.getIdentifierLoc())); 993 } 994 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 995 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 996 if (FTI.TypeQuals & QualType::Const) 997 Diag(D.getIdentifierLoc(), 998 diag::err_invalid_qualified_destructor, 999 "const", 1000 SourceRange(D.getIdentifierLoc())); 1001 if (FTI.TypeQuals & QualType::Volatile) 1002 Diag(D.getIdentifierLoc(), 1003 diag::err_invalid_qualified_destructor, 1004 "volatile", 1005 SourceRange(D.getIdentifierLoc())); 1006 if (FTI.TypeQuals & QualType::Restrict) 1007 Diag(D.getIdentifierLoc(), 1008 diag::err_invalid_qualified_destructor, 1009 "restrict", 1010 SourceRange(D.getIdentifierLoc())); 1011 } 1012 1013 // Make sure we don't have any parameters. 1014 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 1015 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params); 1016 1017 // Delete the parameters. 1018 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1019 if (FTI.NumArgs) { 1020 delete [] FTI.ArgInfo; 1021 FTI.NumArgs = 0; 1022 FTI.ArgInfo = 0; 1023 } 1024 } 1025 1026 // Make sure the destructor isn't variadic. 1027 if (R->getAsFunctionTypeProto()->isVariadic()) 1028 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic); 1029 1030 // Rebuild the function type "R" without any type qualifiers or 1031 // parameters (in case any of the errors above fired) and with 1032 // "void" as the return type, since destructors don't have return 1033 // types. We *always* have to do this, because GetTypeForDeclarator 1034 // will put in a result type of "int" when none was specified. 1035 R = Context.getFunctionType(Context.VoidTy, 0, 0, false, 0); 1036 1037 return isInvalid; 1038} 1039 1040/// CheckConversionDeclarator - Called by ActOnDeclarator to check the 1041/// well-formednes of the conversion function declarator @p D with 1042/// type @p R. If there are any errors in the declarator, this routine 1043/// will emit diagnostics and return true. Otherwise, it will return 1044/// false. Either way, the type @p R will be updated to reflect a 1045/// well-formed type for the conversion operator. 1046bool Sema::CheckConversionDeclarator(Declarator &D, QualType &R, 1047 FunctionDecl::StorageClass& SC) { 1048 bool isInvalid = false; 1049 1050 // C++ [class.conv.fct]p1: 1051 // Neither parameter types nor return type can be specified. The 1052 // type of a conversion function (8.3.5) is “function taking no 1053 // parameter returning conversion-type-id.” 1054 if (SC == FunctionDecl::Static) { 1055 Diag(D.getIdentifierLoc(), 1056 diag::err_conv_function_not_member, 1057 "static", 1058 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 1059 SourceRange(D.getIdentifierLoc())); 1060 isInvalid = true; 1061 SC = FunctionDecl::None; 1062 } 1063 if (D.getDeclSpec().hasTypeSpecifier()) { 1064 // Conversion functions don't have return types, but the parser will 1065 // happily parse something like: 1066 // 1067 // class X { 1068 // float operator bool(); 1069 // }; 1070 // 1071 // The return type will be changed later anyway. 1072 Diag(D.getIdentifierLoc(), 1073 diag::err_conv_function_return_type, 1074 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 1075 SourceRange(D.getIdentifierLoc())); 1076 } 1077 1078 // Make sure we don't have any parameters. 1079 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 1080 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params); 1081 1082 // Delete the parameters. 1083 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1084 if (FTI.NumArgs) { 1085 delete [] FTI.ArgInfo; 1086 FTI.NumArgs = 0; 1087 FTI.ArgInfo = 0; 1088 } 1089 } 1090 1091 // Make sure the conversion function isn't variadic. 1092 if (R->getAsFunctionTypeProto()->isVariadic()) 1093 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic); 1094 1095 // C++ [class.conv.fct]p4: 1096 // The conversion-type-id shall not represent a function type nor 1097 // an array type. 1098 QualType ConvType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1099 if (ConvType->isArrayType()) { 1100 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array); 1101 ConvType = Context.getPointerType(ConvType); 1102 } else if (ConvType->isFunctionType()) { 1103 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function); 1104 ConvType = Context.getPointerType(ConvType); 1105 } 1106 1107 // Rebuild the function type "R" without any parameters (in case any 1108 // of the errors above fired) and with the conversion type as the 1109 // return type. 1110 R = Context.getFunctionType(ConvType, 0, 0, false, 1111 R->getAsFunctionTypeProto()->getTypeQuals()); 1112 1113 return isInvalid; 1114} 1115 1116/// ActOnConstructorDeclarator - Called by ActOnDeclarator to complete 1117/// the declaration of the given C++ constructor ConDecl that was 1118/// built from declarator D. This routine is responsible for checking 1119/// that the newly-created constructor declaration is well-formed and 1120/// for recording it in the C++ class. Example: 1121/// 1122/// @code 1123/// class X { 1124/// X(); // X::X() will be the ConDecl. 1125/// }; 1126/// @endcode 1127Sema::DeclTy *Sema::ActOnConstructorDeclarator(CXXConstructorDecl *ConDecl) { 1128 assert(ConDecl && "Expected to receive a constructor declaration"); 1129 1130 // Check default arguments on the constructor 1131 CheckCXXDefaultArguments(ConDecl); 1132 1133 CXXRecordDecl *ClassDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 1134 if (!ClassDecl) { 1135 ConDecl->setInvalidDecl(); 1136 return ConDecl; 1137 } 1138 1139 // Make sure this constructor is an overload of the existing 1140 // constructors. 1141 OverloadedFunctionDecl::function_iterator MatchedDecl; 1142 if (!IsOverload(ConDecl, ClassDecl->getConstructors(), MatchedDecl)) { 1143 Diag(ConDecl->getLocation(), 1144 diag::err_constructor_redeclared, 1145 SourceRange(ConDecl->getLocation())); 1146 Diag((*MatchedDecl)->getLocation(), 1147 diag::err_previous_declaration, 1148 SourceRange((*MatchedDecl)->getLocation())); 1149 ConDecl->setInvalidDecl(); 1150 return ConDecl; 1151 } 1152 1153 1154 // C++ [class.copy]p3: 1155 // A declaration of a constructor for a class X is ill-formed if 1156 // its first parameter is of type (optionally cv-qualified) X and 1157 // either there are no other parameters or else all other 1158 // parameters have default arguments. 1159 if ((ConDecl->getNumParams() == 1) || 1160 (ConDecl->getNumParams() > 1 && 1161 ConDecl->getParamDecl(1)->getDefaultArg() != 0)) { 1162 QualType ParamType = ConDecl->getParamDecl(0)->getType(); 1163 QualType ClassTy = Context.getTagDeclType( 1164 const_cast<CXXRecordDecl*>(ConDecl->getParent())); 1165 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { 1166 Diag(ConDecl->getLocation(), 1167 diag::err_constructor_byvalue_arg, 1168 SourceRange(ConDecl->getParamDecl(0)->getLocation())); 1169 ConDecl->setInvalidDecl(); 1170 return ConDecl; 1171 } 1172 } 1173 1174 // Add this constructor to the set of constructors of the current 1175 // class. 1176 ClassDecl->addConstructor(Context, ConDecl); 1177 return (DeclTy *)ConDecl; 1178} 1179 1180/// ActOnDestructorDeclarator - Called by ActOnDeclarator to complete 1181/// the declaration of the given C++ @p Destructor. This routine is 1182/// responsible for recording the destructor in the C++ class, if 1183/// possible. 1184Sema::DeclTy *Sema::ActOnDestructorDeclarator(CXXDestructorDecl *Destructor) { 1185 assert(Destructor && "Expected to receive a destructor declaration"); 1186 1187 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1188 1189 // Make sure we aren't redeclaring the destructor. 1190 if (CXXDestructorDecl *PrevDestructor = ClassDecl->getDestructor()) { 1191 Diag(Destructor->getLocation(), diag::err_destructor_redeclared); 1192 Diag(PrevDestructor->getLocation(), 1193 PrevDestructor->isThisDeclarationADefinition()? 1194 diag::err_previous_definition 1195 : diag::err_previous_declaration); 1196 Destructor->setInvalidDecl(); 1197 return Destructor; 1198 } 1199 1200 ClassDecl->setDestructor(Destructor); 1201 return (DeclTy *)Destructor; 1202} 1203 1204/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete 1205/// the declaration of the given C++ conversion function. This routine 1206/// is responsible for recording the conversion function in the C++ 1207/// class, if possible. 1208Sema::DeclTy *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) { 1209 assert(Conversion && "Expected to receive a conversion function declaration"); 1210 1211 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1212 1213 // Make sure we aren't redeclaring the conversion function. 1214 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType()); 1215 OverloadedFunctionDecl *Conversions = ClassDecl->getConversionFunctions(); 1216 for (OverloadedFunctionDecl::function_iterator Func 1217 = Conversions->function_begin(); 1218 Func != Conversions->function_end(); ++Func) { 1219 CXXConversionDecl *OtherConv = cast<CXXConversionDecl>(*Func); 1220 if (ConvType == Context.getCanonicalType(OtherConv->getConversionType())) { 1221 Diag(Conversion->getLocation(), diag::err_conv_function_redeclared); 1222 Diag(OtherConv->getLocation(), 1223 OtherConv->isThisDeclarationADefinition()? 1224 diag::err_previous_definition 1225 : diag::err_previous_declaration); 1226 Conversion->setInvalidDecl(); 1227 return (DeclTy *)Conversion; 1228 } 1229 } 1230 1231 // C++ [class.conv.fct]p1: 1232 // [...] A conversion function is never used to convert a 1233 // (possibly cv-qualified) object to the (possibly cv-qualified) 1234 // same object type (or a reference to it), to a (possibly 1235 // cv-qualified) base class of that type (or a reference to it), 1236 // or to (possibly cv-qualified) void. 1237 // FIXME: Suppress this warning if the conversion function ends up 1238 // being a virtual function that overrides a virtual function in a 1239 // base class. 1240 QualType ClassType 1241 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl)); 1242 if (const ReferenceType *ConvTypeRef = ConvType->getAsReferenceType()) 1243 ConvType = ConvTypeRef->getPointeeType(); 1244 if (ConvType->isRecordType()) { 1245 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType(); 1246 if (ConvType == ClassType) 1247 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used, 1248 ClassType.getAsString()); 1249 else if (IsDerivedFrom(ClassType, ConvType)) 1250 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used, 1251 ClassType.getAsString(), 1252 ConvType.getAsString()); 1253 } else if (ConvType->isVoidType()) { 1254 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used, 1255 ClassType.getAsString(), ConvType.getAsString()); 1256 } 1257 1258 ClassDecl->addConversionFunction(Context, Conversion); 1259 1260 return (DeclTy *)Conversion; 1261} 1262 1263//===----------------------------------------------------------------------===// 1264// Namespace Handling 1265//===----------------------------------------------------------------------===// 1266 1267/// ActOnStartNamespaceDef - This is called at the start of a namespace 1268/// definition. 1269Sema::DeclTy *Sema::ActOnStartNamespaceDef(Scope *NamespcScope, 1270 SourceLocation IdentLoc, 1271 IdentifierInfo *II, 1272 SourceLocation LBrace) { 1273 NamespaceDecl *Namespc = 1274 NamespaceDecl::Create(Context, CurContext, IdentLoc, II); 1275 Namespc->setLBracLoc(LBrace); 1276 1277 Scope *DeclRegionScope = NamespcScope->getParent(); 1278 1279 if (II) { 1280 // C++ [namespace.def]p2: 1281 // The identifier in an original-namespace-definition shall not have been 1282 // previously defined in the declarative region in which the 1283 // original-namespace-definition appears. The identifier in an 1284 // original-namespace-definition is the name of the namespace. Subsequently 1285 // in that declarative region, it is treated as an original-namespace-name. 1286 1287 Decl *PrevDecl = 1288 LookupDecl(II, Decl::IDNS_Tag | Decl::IDNS_Ordinary, DeclRegionScope, 0, 1289 /*enableLazyBuiltinCreation=*/false); 1290 1291 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, DeclRegionScope)) { 1292 if (NamespaceDecl *OrigNS = dyn_cast<NamespaceDecl>(PrevDecl)) { 1293 // This is an extended namespace definition. 1294 // Attach this namespace decl to the chain of extended namespace 1295 // definitions. 1296 NamespaceDecl *NextNS = OrigNS; 1297 while (NextNS->getNextNamespace()) 1298 NextNS = NextNS->getNextNamespace(); 1299 1300 NextNS->setNextNamespace(Namespc); 1301 Namespc->setOriginalNamespace(OrigNS); 1302 1303 // We won't add this decl to the current scope. We want the namespace 1304 // name to return the original namespace decl during a name lookup. 1305 } else { 1306 // This is an invalid name redefinition. 1307 Diag(Namespc->getLocation(), diag::err_redefinition_different_kind, 1308 Namespc->getName()); 1309 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1310 Namespc->setInvalidDecl(); 1311 // Continue on to push Namespc as current DeclContext and return it. 1312 } 1313 } else { 1314 // This namespace name is declared for the first time. 1315 PushOnScopeChains(Namespc, DeclRegionScope); 1316 } 1317 } 1318 else { 1319 // FIXME: Handle anonymous namespaces 1320 } 1321 1322 // Although we could have an invalid decl (i.e. the namespace name is a 1323 // redefinition), push it as current DeclContext and try to continue parsing. 1324 PushDeclContext(Namespc->getOriginalNamespace()); 1325 return Namespc; 1326} 1327 1328/// ActOnFinishNamespaceDef - This callback is called after a namespace is 1329/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. 1330void Sema::ActOnFinishNamespaceDef(DeclTy *D, SourceLocation RBrace) { 1331 Decl *Dcl = static_cast<Decl *>(D); 1332 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); 1333 assert(Namespc && "Invalid parameter, expected NamespaceDecl"); 1334 Namespc->setRBracLoc(RBrace); 1335 PopDeclContext(); 1336} 1337 1338 1339/// AddCXXDirectInitializerToDecl - This action is called immediately after 1340/// ActOnDeclarator, when a C++ direct initializer is present. 1341/// e.g: "int x(1);" 1342void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc, 1343 ExprTy **ExprTys, unsigned NumExprs, 1344 SourceLocation *CommaLocs, 1345 SourceLocation RParenLoc) { 1346 assert(NumExprs != 0 && ExprTys && "missing expressions"); 1347 Decl *RealDecl = static_cast<Decl *>(Dcl); 1348 1349 // If there is no declaration, there was an error parsing it. Just ignore 1350 // the initializer. 1351 if (RealDecl == 0) { 1352 for (unsigned i = 0; i != NumExprs; ++i) 1353 delete static_cast<Expr *>(ExprTys[i]); 1354 return; 1355 } 1356 1357 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1358 if (!VDecl) { 1359 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 1360 RealDecl->setInvalidDecl(); 1361 return; 1362 } 1363 1364 // We will treat direct-initialization as a copy-initialization: 1365 // int x(1); -as-> int x = 1; 1366 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); 1367 // 1368 // Clients that want to distinguish between the two forms, can check for 1369 // direct initializer using VarDecl::hasCXXDirectInitializer(). 1370 // A major benefit is that clients that don't particularly care about which 1371 // exactly form was it (like the CodeGen) can handle both cases without 1372 // special case code. 1373 1374 // C++ 8.5p11: 1375 // The form of initialization (using parentheses or '=') is generally 1376 // insignificant, but does matter when the entity being initialized has a 1377 // class type. 1378 QualType DeclInitType = VDecl->getType(); 1379 if (const ArrayType *Array = Context.getAsArrayType(DeclInitType)) 1380 DeclInitType = Array->getElementType(); 1381 1382 if (VDecl->getType()->isRecordType()) { 1383 CXXConstructorDecl *Constructor 1384 = PerformInitializationByConstructor(DeclInitType, 1385 (Expr **)ExprTys, NumExprs, 1386 VDecl->getLocation(), 1387 SourceRange(VDecl->getLocation(), 1388 RParenLoc), 1389 VDecl->getName(), 1390 IK_Direct); 1391 if (!Constructor) { 1392 RealDecl->setInvalidDecl(); 1393 } 1394 1395 // Let clients know that initialization was done with a direct 1396 // initializer. 1397 VDecl->setCXXDirectInitializer(true); 1398 1399 // FIXME: Add ExprTys and Constructor to the RealDecl as part of 1400 // the initializer. 1401 return; 1402 } 1403 1404 if (NumExprs > 1) { 1405 Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg, 1406 SourceRange(VDecl->getLocation(), RParenLoc)); 1407 RealDecl->setInvalidDecl(); 1408 return; 1409 } 1410 1411 // Let clients know that initialization was done with a direct initializer. 1412 VDecl->setCXXDirectInitializer(true); 1413 1414 assert(NumExprs == 1 && "Expected 1 expression"); 1415 // Set the init expression, handles conversions. 1416 AddInitializerToDecl(Dcl, ExprTys[0]); 1417} 1418 1419/// PerformInitializationByConstructor - Perform initialization by 1420/// constructor (C++ [dcl.init]p14), which may occur as part of 1421/// direct-initialization or copy-initialization. We are initializing 1422/// an object of type @p ClassType with the given arguments @p 1423/// Args. @p Loc is the location in the source code where the 1424/// initializer occurs (e.g., a declaration, member initializer, 1425/// functional cast, etc.) while @p Range covers the whole 1426/// initialization. @p InitEntity is the entity being initialized, 1427/// which may by the name of a declaration or a type. @p Kind is the 1428/// kind of initialization we're performing, which affects whether 1429/// explicit constructors will be considered. When successful, returns 1430/// the constructor that will be used to perform the initialization; 1431/// when the initialization fails, emits a diagnostic and returns 1432/// null. 1433CXXConstructorDecl * 1434Sema::PerformInitializationByConstructor(QualType ClassType, 1435 Expr **Args, unsigned NumArgs, 1436 SourceLocation Loc, SourceRange Range, 1437 std::string InitEntity, 1438 InitializationKind Kind) { 1439 const RecordType *ClassRec = ClassType->getAsRecordType(); 1440 assert(ClassRec && "Can only initialize a class type here"); 1441 1442 // C++ [dcl.init]p14: 1443 // 1444 // If the initialization is direct-initialization, or if it is 1445 // copy-initialization where the cv-unqualified version of the 1446 // source type is the same class as, or a derived class of, the 1447 // class of the destination, constructors are considered. The 1448 // applicable constructors are enumerated (13.3.1.3), and the 1449 // best one is chosen through overload resolution (13.3). The 1450 // constructor so selected is called to initialize the object, 1451 // with the initializer expression(s) as its argument(s). If no 1452 // constructor applies, or the overload resolution is ambiguous, 1453 // the initialization is ill-formed. 1454 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1455 OverloadCandidateSet CandidateSet; 1456 1457 // Add constructors to the overload set. 1458 OverloadedFunctionDecl *Constructors 1459 = const_cast<OverloadedFunctionDecl *>(ClassDecl->getConstructors()); 1460 for (OverloadedFunctionDecl::function_iterator Con 1461 = Constructors->function_begin(); 1462 Con != Constructors->function_end(); ++Con) { 1463 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 1464 if ((Kind == IK_Direct) || 1465 (Kind == IK_Copy && Constructor->isConvertingConstructor()) || 1466 (Kind == IK_Default && Constructor->isDefaultConstructor())) 1467 AddOverloadCandidate(Constructor, Args, NumArgs, CandidateSet); 1468 } 1469 1470 OverloadCandidateSet::iterator Best; 1471 switch (BestViableFunction(CandidateSet, Best)) { 1472 case OR_Success: 1473 // We found a constructor. Return it. 1474 return cast<CXXConstructorDecl>(Best->Function); 1475 1476 case OR_No_Viable_Function: 1477 if (CandidateSet.empty()) 1478 Diag(Loc, diag::err_ovl_no_viable_function_in_init, 1479 InitEntity, Range); 1480 else { 1481 Diag(Loc, diag::err_ovl_no_viable_function_in_init_with_cands, 1482 InitEntity, Range); 1483 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1484 } 1485 return 0; 1486 1487 case OR_Ambiguous: 1488 Diag(Loc, diag::err_ovl_ambiguous_init, 1489 InitEntity, Range); 1490 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1491 return 0; 1492 } 1493 1494 return 0; 1495} 1496 1497/// CompareReferenceRelationship - Compare the two types T1 and T2 to 1498/// determine whether they are reference-related, 1499/// reference-compatible, reference-compatible with added 1500/// qualification, or incompatible, for use in C++ initialization by 1501/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 1502/// type, and the first type (T1) is the pointee type of the reference 1503/// type being initialized. 1504Sema::ReferenceCompareResult 1505Sema::CompareReferenceRelationship(QualType T1, QualType T2, 1506 bool& DerivedToBase) { 1507 assert(!T1->isReferenceType() && "T1 must be the pointee type of the reference type"); 1508 assert(!T2->isReferenceType() && "T2 cannot be a reference type"); 1509 1510 T1 = Context.getCanonicalType(T1); 1511 T2 = Context.getCanonicalType(T2); 1512 QualType UnqualT1 = T1.getUnqualifiedType(); 1513 QualType UnqualT2 = T2.getUnqualifiedType(); 1514 1515 // C++ [dcl.init.ref]p4: 1516 // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is 1517 // reference-related to “cv2 T2” if T1 is the same type as T2, or 1518 // T1 is a base class of T2. 1519 if (UnqualT1 == UnqualT2) 1520 DerivedToBase = false; 1521 else if (IsDerivedFrom(UnqualT2, UnqualT1)) 1522 DerivedToBase = true; 1523 else 1524 return Ref_Incompatible; 1525 1526 // At this point, we know that T1 and T2 are reference-related (at 1527 // least). 1528 1529 // C++ [dcl.init.ref]p4: 1530 // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is 1531 // reference-related to T2 and cv1 is the same cv-qualification 1532 // as, or greater cv-qualification than, cv2. For purposes of 1533 // overload resolution, cases for which cv1 is greater 1534 // cv-qualification than cv2 are identified as 1535 // reference-compatible with added qualification (see 13.3.3.2). 1536 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 1537 return Ref_Compatible; 1538 else if (T1.isMoreQualifiedThan(T2)) 1539 return Ref_Compatible_With_Added_Qualification; 1540 else 1541 return Ref_Related; 1542} 1543 1544/// CheckReferenceInit - Check the initialization of a reference 1545/// variable with the given initializer (C++ [dcl.init.ref]). Init is 1546/// the initializer (either a simple initializer or an initializer 1547/// list), and DeclType is the type of the declaration. When ICS is 1548/// non-null, this routine will compute the implicit conversion 1549/// sequence according to C++ [over.ics.ref] and will not produce any 1550/// diagnostics; when ICS is null, it will emit diagnostics when any 1551/// errors are found. Either way, a return value of true indicates 1552/// that there was a failure, a return value of false indicates that 1553/// the reference initialization succeeded. 1554/// 1555/// When @p SuppressUserConversions, user-defined conversions are 1556/// suppressed. 1557bool 1558Sema::CheckReferenceInit(Expr *&Init, QualType &DeclType, 1559 ImplicitConversionSequence *ICS, 1560 bool SuppressUserConversions) { 1561 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 1562 1563 QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); 1564 QualType T2 = Init->getType(); 1565 1566 // If the initializer is the address of an overloaded function, try 1567 // to resolve the overloaded function. If all goes well, T2 is the 1568 // type of the resulting function. 1569 if (T2->isOverloadType()) { 1570 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Init, DeclType, 1571 ICS != 0); 1572 if (Fn) { 1573 // Since we're performing this reference-initialization for 1574 // real, update the initializer with the resulting function. 1575 if (!ICS) 1576 FixOverloadedFunctionReference(Init, Fn); 1577 1578 T2 = Fn->getType(); 1579 } 1580 } 1581 1582 // Compute some basic properties of the types and the initializer. 1583 bool DerivedToBase = false; 1584 Expr::isLvalueResult InitLvalue = Init->isLvalue(Context); 1585 ReferenceCompareResult RefRelationship 1586 = CompareReferenceRelationship(T1, T2, DerivedToBase); 1587 1588 // Most paths end in a failed conversion. 1589 if (ICS) 1590 ICS->ConversionKind = ImplicitConversionSequence::BadConversion; 1591 1592 // C++ [dcl.init.ref]p5: 1593 // A reference to type “cv1 T1” is initialized by an expression 1594 // of type “cv2 T2” as follows: 1595 1596 // -- If the initializer expression 1597 1598 bool BindsDirectly = false; 1599 // -- is an lvalue (but is not a bit-field), and “cv1 T1” is 1600 // reference-compatible with “cv2 T2,” or 1601 // 1602 // Note that the bit-field check is skipped if we are just computing 1603 // the implicit conversion sequence (C++ [over.best.ics]p2). 1604 if (InitLvalue == Expr::LV_Valid && (ICS || !Init->isBitField()) && 1605 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1606 BindsDirectly = true; 1607 1608 if (ICS) { 1609 // C++ [over.ics.ref]p1: 1610 // When a parameter of reference type binds directly (8.5.3) 1611 // to an argument expression, the implicit conversion sequence 1612 // is the identity conversion, unless the argument expression 1613 // has a type that is a derived class of the parameter type, 1614 // in which case the implicit conversion sequence is a 1615 // derived-to-base Conversion (13.3.3.1). 1616 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1617 ICS->Standard.First = ICK_Identity; 1618 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1619 ICS->Standard.Third = ICK_Identity; 1620 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1621 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1622 ICS->Standard.ReferenceBinding = true; 1623 ICS->Standard.DirectBinding = true; 1624 1625 // Nothing more to do: the inaccessibility/ambiguity check for 1626 // derived-to-base conversions is suppressed when we're 1627 // computing the implicit conversion sequence (C++ 1628 // [over.best.ics]p2). 1629 return false; 1630 } else { 1631 // Perform the conversion. 1632 // FIXME: Binding to a subobject of the lvalue is going to require 1633 // more AST annotation than this. 1634 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1635 } 1636 } 1637 1638 // -- has a class type (i.e., T2 is a class type) and can be 1639 // implicitly converted to an lvalue of type “cv3 T3,” 1640 // where “cv1 T1” is reference-compatible with “cv3 T3” 1641 // 92) (this conversion is selected by enumerating the 1642 // applicable conversion functions (13.3.1.6) and choosing 1643 // the best one through overload resolution (13.3)), 1644 if (!SuppressUserConversions && T2->isRecordType()) { 1645 // FIXME: Look for conversions in base classes! 1646 CXXRecordDecl *T2RecordDecl 1647 = dyn_cast<CXXRecordDecl>(T2->getAsRecordType()->getDecl()); 1648 1649 OverloadCandidateSet CandidateSet; 1650 OverloadedFunctionDecl *Conversions 1651 = T2RecordDecl->getConversionFunctions(); 1652 for (OverloadedFunctionDecl::function_iterator Func 1653 = Conversions->function_begin(); 1654 Func != Conversions->function_end(); ++Func) { 1655 CXXConversionDecl *Conv = cast<CXXConversionDecl>(*Func); 1656 1657 // If the conversion function doesn't return a reference type, 1658 // it can't be considered for this conversion. 1659 // FIXME: This will change when we support rvalue references. 1660 if (Conv->getConversionType()->isReferenceType()) 1661 AddConversionCandidate(Conv, Init, DeclType, CandidateSet); 1662 } 1663 1664 OverloadCandidateSet::iterator Best; 1665 switch (BestViableFunction(CandidateSet, Best)) { 1666 case OR_Success: 1667 // This is a direct binding. 1668 BindsDirectly = true; 1669 1670 if (ICS) { 1671 // C++ [over.ics.ref]p1: 1672 // 1673 // [...] If the parameter binds directly to the result of 1674 // applying a conversion function to the argument 1675 // expression, the implicit conversion sequence is a 1676 // user-defined conversion sequence (13.3.3.1.2), with the 1677 // second standard conversion sequence either an identity 1678 // conversion or, if the conversion function returns an 1679 // entity of a type that is a derived class of the parameter 1680 // type, a derived-to-base Conversion. 1681 ICS->ConversionKind = ImplicitConversionSequence::UserDefinedConversion; 1682 ICS->UserDefined.Before = Best->Conversions[0].Standard; 1683 ICS->UserDefined.After = Best->FinalConversion; 1684 ICS->UserDefined.ConversionFunction = Best->Function; 1685 assert(ICS->UserDefined.After.ReferenceBinding && 1686 ICS->UserDefined.After.DirectBinding && 1687 "Expected a direct reference binding!"); 1688 return false; 1689 } else { 1690 // Perform the conversion. 1691 // FIXME: Binding to a subobject of the lvalue is going to require 1692 // more AST annotation than this. 1693 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1694 } 1695 break; 1696 1697 case OR_Ambiguous: 1698 assert(false && "Ambiguous reference binding conversions not implemented."); 1699 return true; 1700 1701 case OR_No_Viable_Function: 1702 // There was no suitable conversion; continue with other checks. 1703 break; 1704 } 1705 } 1706 1707 if (BindsDirectly) { 1708 // C++ [dcl.init.ref]p4: 1709 // [...] In all cases where the reference-related or 1710 // reference-compatible relationship of two types is used to 1711 // establish the validity of a reference binding, and T1 is a 1712 // base class of T2, a program that necessitates such a binding 1713 // is ill-formed if T1 is an inaccessible (clause 11) or 1714 // ambiguous (10.2) base class of T2. 1715 // 1716 // Note that we only check this condition when we're allowed to 1717 // complain about errors, because we should not be checking for 1718 // ambiguity (or inaccessibility) unless the reference binding 1719 // actually happens. 1720 if (DerivedToBase) 1721 return CheckDerivedToBaseConversion(T2, T1, 1722 Init->getSourceRange().getBegin(), 1723 Init->getSourceRange()); 1724 else 1725 return false; 1726 } 1727 1728 // -- Otherwise, the reference shall be to a non-volatile const 1729 // type (i.e., cv1 shall be const). 1730 if (T1.getCVRQualifiers() != QualType::Const) { 1731 if (!ICS) 1732 Diag(Init->getSourceRange().getBegin(), 1733 diag::err_not_reference_to_const_init, 1734 T1.getAsString(), 1735 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1736 T2.getAsString(), Init->getSourceRange()); 1737 return true; 1738 } 1739 1740 // -- If the initializer expression is an rvalue, with T2 a 1741 // class type, and “cv1 T1” is reference-compatible with 1742 // “cv2 T2,” the reference is bound in one of the 1743 // following ways (the choice is implementation-defined): 1744 // 1745 // -- The reference is bound to the object represented by 1746 // the rvalue (see 3.10) or to a sub-object within that 1747 // object. 1748 // 1749 // -- A temporary of type “cv1 T2” [sic] is created, and 1750 // a constructor is called to copy the entire rvalue 1751 // object into the temporary. The reference is bound to 1752 // the temporary or to a sub-object within the 1753 // temporary. 1754 // 1755 // 1756 // The constructor that would be used to make the copy 1757 // shall be callable whether or not the copy is actually 1758 // done. 1759 // 1760 // Note that C++0x [dcl.ref.init]p5 takes away this implementation 1761 // freedom, so we will always take the first option and never build 1762 // a temporary in this case. FIXME: We will, however, have to check 1763 // for the presence of a copy constructor in C++98/03 mode. 1764 if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && 1765 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1766 if (ICS) { 1767 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1768 ICS->Standard.First = ICK_Identity; 1769 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1770 ICS->Standard.Third = ICK_Identity; 1771 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1772 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1773 ICS->Standard.ReferenceBinding = true; 1774 ICS->Standard.DirectBinding = false; 1775 } else { 1776 // FIXME: Binding to a subobject of the rvalue is going to require 1777 // more AST annotation than this. 1778 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1779 } 1780 return false; 1781 } 1782 1783 // -- Otherwise, a temporary of type “cv1 T1” is created and 1784 // initialized from the initializer expression using the 1785 // rules for a non-reference copy initialization (8.5). The 1786 // reference is then bound to the temporary. If T1 is 1787 // reference-related to T2, cv1 must be the same 1788 // cv-qualification as, or greater cv-qualification than, 1789 // cv2; otherwise, the program is ill-formed. 1790 if (RefRelationship == Ref_Related) { 1791 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 1792 // we would be reference-compatible or reference-compatible with 1793 // added qualification. But that wasn't the case, so the reference 1794 // initialization fails. 1795 if (!ICS) 1796 Diag(Init->getSourceRange().getBegin(), 1797 diag::err_reference_init_drops_quals, 1798 T1.getAsString(), 1799 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1800 T2.getAsString(), Init->getSourceRange()); 1801 return true; 1802 } 1803 1804 // Actually try to convert the initializer to T1. 1805 if (ICS) { 1806 /// C++ [over.ics.ref]p2: 1807 /// 1808 /// When a parameter of reference type is not bound directly to 1809 /// an argument expression, the conversion sequence is the one 1810 /// required to convert the argument expression to the 1811 /// underlying type of the reference according to 1812 /// 13.3.3.1. Conceptually, this conversion sequence corresponds 1813 /// to copy-initializing a temporary of the underlying type with 1814 /// the argument expression. Any difference in top-level 1815 /// cv-qualification is subsumed by the initialization itself 1816 /// and does not constitute a conversion. 1817 *ICS = TryImplicitConversion(Init, T1, SuppressUserConversions); 1818 return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; 1819 } else { 1820 return PerformImplicitConversion(Init, T1); 1821 } 1822} 1823 1824/// CheckOverloadedOperatorDeclaration - Check whether the declaration 1825/// of this overloaded operator is well-formed. If so, returns false; 1826/// otherwise, emits appropriate diagnostics and returns true. 1827bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) { 1828 assert(FnDecl && FnDecl->getOverloadedOperator() != OO_None && 1829 "Expected an overloaded operator declaration"); 1830 1831 bool IsInvalid = false; 1832 1833 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator(); 1834 1835 // C++ [over.oper]p5: 1836 // The allocation and deallocation functions, operator new, 1837 // operator new[], operator delete and operator delete[], are 1838 // described completely in 3.7.3. The attributes and restrictions 1839 // found in the rest of this subclause do not apply to them unless 1840 // explicitly stated in 3.7.3. 1841 // FIXME: Write a separate routine for checking this. For now, just 1842 // allow it. 1843 if (Op == OO_New || Op == OO_Array_New || 1844 Op == OO_Delete || Op == OO_Array_Delete) 1845 return false; 1846 1847 // C++ [over.oper]p6: 1848 // An operator function shall either be a non-static member 1849 // function or be a non-member function and have at least one 1850 // parameter whose type is a class, a reference to a class, an 1851 // enumeration, or a reference to an enumeration. 1852 CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl); 1853 if (MethodDecl) { 1854 if (MethodDecl->isStatic()) { 1855 Diag(FnDecl->getLocation(), 1856 diag::err_operator_overload_static, 1857 FnDecl->getName(), 1858 SourceRange(FnDecl->getLocation())); 1859 IsInvalid = true; 1860 1861 // Pretend this isn't a member function; it'll supress 1862 // additional, unnecessary error messages. 1863 MethodDecl = 0; 1864 } 1865 } else { 1866 bool ClassOrEnumParam = false; 1867 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 1868 Param != FnDecl->param_end(); ++Param) { 1869 QualType ParamType = (*Param)->getType(); 1870 if (const ReferenceType *RefType = ParamType->getAsReferenceType()) 1871 ParamType = RefType->getPointeeType(); 1872 if (ParamType->isRecordType() || ParamType->isEnumeralType()) { 1873 ClassOrEnumParam = true; 1874 break; 1875 } 1876 } 1877 1878 if (!ClassOrEnumParam) { 1879 Diag(FnDecl->getLocation(), 1880 diag::err_operator_overload_needs_class_or_enum, 1881 FnDecl->getName(), 1882 SourceRange(FnDecl->getLocation())); 1883 IsInvalid = true; 1884 } 1885 } 1886 1887 // C++ [over.oper]p8: 1888 // An operator function cannot have default arguments (8.3.6), 1889 // except where explicitly stated below. 1890 // 1891 // Only the function-call operator allows default arguments 1892 // (C++ [over.call]p1). 1893 if (Op != OO_Call) { 1894 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 1895 Param != FnDecl->param_end(); ++Param) { 1896 if (Expr *DefArg = (*Param)->getDefaultArg()) { 1897 Diag((*Param)->getLocation(), 1898 diag::err_operator_overload_default_arg, 1899 DefArg->getSourceRange()); 1900 IsInvalid = true; 1901 } 1902 } 1903 } 1904 1905 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = { 1906 { false, false, false } 1907#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \ 1908 , { Unary, Binary, MemberOnly } 1909#include "clang/Basic/OperatorKinds.def" 1910 }; 1911 1912 bool CanBeUnaryOperator = OperatorUses[Op][0]; 1913 bool CanBeBinaryOperator = OperatorUses[Op][1]; 1914 bool MustBeMemberOperator = OperatorUses[Op][2]; 1915 1916 // C++ [over.oper]p8: 1917 // [...] Operator functions cannot have more or fewer parameters 1918 // than the number required for the corresponding operator, as 1919 // described in the rest of this subclause. 1920 unsigned NumParams = FnDecl->getNumParams() + (MethodDecl? 1 : 0); 1921 if (Op != OO_Call && 1922 ((NumParams == 1 && !CanBeUnaryOperator) || 1923 (NumParams == 2 && !CanBeBinaryOperator) || 1924 (NumParams < 1) || (NumParams > 2))) { 1925 // We have the wrong number of parameters. 1926 std::string NumParamsStr = (llvm::APSInt(32) = NumParams).toString(10); 1927 1928 diag::kind DK; 1929 1930 if (CanBeUnaryOperator && CanBeBinaryOperator) { 1931 if (NumParams == 1) 1932 DK = diag::err_operator_overload_must_be_unary_or_binary; 1933 else 1934 DK = diag::err_operator_overload_must_be_unary_or_binary; 1935 } else if (CanBeUnaryOperator) { 1936 if (NumParams == 1) 1937 DK = diag::err_operator_overload_must_be_unary; 1938 else 1939 DK = diag::err_operator_overload_must_be_unary_plural; 1940 } else if (CanBeBinaryOperator) { 1941 if (NumParams == 1) 1942 DK = diag::err_operator_overload_must_be_binary; 1943 else 1944 DK = diag::err_operator_overload_must_be_binary_plural; 1945 } else { 1946 assert(false && "All non-call overloaded operators are unary or binary!"); 1947 } 1948 1949 Diag(FnDecl->getLocation(), DK, 1950 FnDecl->getName(), NumParamsStr, 1951 SourceRange(FnDecl->getLocation())); 1952 IsInvalid = true; 1953 } 1954 1955 // Overloaded operators cannot be variadic. 1956 if (FnDecl->getType()->getAsFunctionTypeProto()->isVariadic()) { 1957 Diag(FnDecl->getLocation(), 1958 diag::err_operator_overload_variadic, 1959 SourceRange(FnDecl->getLocation())); 1960 IsInvalid = true; 1961 } 1962 1963 // Some operators must be non-static member functions. 1964 if (MustBeMemberOperator && !MethodDecl) { 1965 Diag(FnDecl->getLocation(), 1966 diag::err_operator_overload_must_be_member, 1967 FnDecl->getName(), 1968 SourceRange(FnDecl->getLocation())); 1969 IsInvalid = true; 1970 } 1971 1972 // C++ [over.inc]p1: 1973 // The user-defined function called operator++ implements the 1974 // prefix and postfix ++ operator. If this function is a member 1975 // function with no parameters, or a non-member function with one 1976 // parameter of class or enumeration type, it defines the prefix 1977 // increment operator ++ for objects of that type. If the function 1978 // is a member function with one parameter (which shall be of type 1979 // int) or a non-member function with two parameters (the second 1980 // of which shall be of type int), it defines the postfix 1981 // increment operator ++ for objects of that type. 1982 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) { 1983 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1); 1984 bool ParamIsInt = false; 1985 if (const BuiltinType *BT = LastParam->getType()->getAsBuiltinType()) 1986 ParamIsInt = BT->getKind() == BuiltinType::Int; 1987 1988 if (!ParamIsInt) { 1989 diag::kind DK; 1990 if (Op == OO_PlusPlus) { 1991 if (MethodDecl) 1992 DK = diag::err_operator_overload_post_inc_must_be_int_member; 1993 else 1994 DK = diag::err_operator_overload_post_inc_must_be_int; 1995 } else { 1996 if (MethodDecl) 1997 DK = diag::err_operator_overload_post_dec_must_be_int_member; 1998 else 1999 DK = diag::err_operator_overload_post_dec_must_be_int; 2000 } 2001 Diag(LastParam->getLocation(), DK, 2002 Context.getCanonicalType(LastParam->getType()).getAsString(), 2003 SourceRange(FnDecl->getLocation())); 2004 IsInvalid = true; 2005 } 2006 } 2007 2008 return IsInvalid; 2009} 2010