SemaDeclCXX.cpp revision 10bd36882406cdf4805e35add1ce2f11ab9ae152
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/ADT/StringExtras.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->getName(), 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->getName(), 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 ExprTy *defarg) { 110 ParmVarDecl *Param = (ParmVarDecl *)param; 111 llvm::OwningPtr<Expr> DefaultArg((Expr *)defarg); 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 return; 119 } 120 121 // C++ [dcl.fct.default]p5 122 // A default argument expression is implicitly converted (clause 123 // 4) to the parameter type. The default argument expression has 124 // the same semantic constraints as the initializer expression in 125 // a declaration of a variable of the parameter type, using the 126 // copy-initialization semantics (8.5). 127 Expr *DefaultArgPtr = DefaultArg.get(); 128 bool DefaultInitFailed = PerformCopyInitialization(DefaultArgPtr, ParamType, 129 "in default argument"); 130 if (DefaultArgPtr != DefaultArg.get()) { 131 DefaultArg.take(); 132 DefaultArg.reset(DefaultArgPtr); 133 } 134 if (DefaultInitFailed) { 135 return; 136 } 137 138 // Check that the default argument is well-formed 139 CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg.get(), this); 140 if (DefaultArgChecker.Visit(DefaultArg.get())) 141 return; 142 143 // Okay: add the default argument to the parameter 144 Param->setDefaultArg(DefaultArg.take()); 145} 146 147/// CheckExtraCXXDefaultArguments - Check for any extra default 148/// arguments in the declarator, which is not a function declaration 149/// or definition and therefore is not permitted to have default 150/// arguments. This routine should be invoked for every declarator 151/// that is not a function declaration or definition. 152void Sema::CheckExtraCXXDefaultArguments(Declarator &D) { 153 // C++ [dcl.fct.default]p3 154 // A default argument expression shall be specified only in the 155 // parameter-declaration-clause of a function declaration or in a 156 // template-parameter (14.1). It shall not be specified for a 157 // parameter pack. If it is specified in a 158 // parameter-declaration-clause, it shall not occur within a 159 // declarator or abstract-declarator of a parameter-declaration. 160 for (unsigned i = 0; i < D.getNumTypeObjects(); ++i) { 161 DeclaratorChunk &chunk = D.getTypeObject(i); 162 if (chunk.Kind == DeclaratorChunk::Function) { 163 for (unsigned argIdx = 0; argIdx < chunk.Fun.NumArgs; ++argIdx) { 164 ParmVarDecl *Param = (ParmVarDecl *)chunk.Fun.ArgInfo[argIdx].Param; 165 if (Param->getDefaultArg()) { 166 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc, 167 Param->getDefaultArg()->getSourceRange()); 168 Param->setDefaultArg(0); 169 } 170 } 171 } 172 } 173} 174 175// MergeCXXFunctionDecl - Merge two declarations of the same C++ 176// function, once we already know that they have the same 177// type. Subroutine of MergeFunctionDecl. 178FunctionDecl * 179Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old) { 180 // C++ [dcl.fct.default]p4: 181 // 182 // For non-template functions, default arguments can be added in 183 // later declarations of a function in the same 184 // scope. Declarations in different scopes have completely 185 // distinct sets of default arguments. That is, declarations in 186 // inner scopes do not acquire default arguments from 187 // declarations in outer scopes, and vice versa. In a given 188 // function declaration, all parameters subsequent to a 189 // parameter with a default argument shall have default 190 // arguments supplied in this or previous declarations. A 191 // default argument shall not be redefined by a later 192 // declaration (not even to the same value). 193 for (unsigned p = 0, NumParams = Old->getNumParams(); p < NumParams; ++p) { 194 ParmVarDecl *OldParam = Old->getParamDecl(p); 195 ParmVarDecl *NewParam = New->getParamDecl(p); 196 197 if(OldParam->getDefaultArg() && NewParam->getDefaultArg()) { 198 Diag(NewParam->getLocation(), 199 diag::err_param_default_argument_redefinition, 200 NewParam->getDefaultArg()->getSourceRange()); 201 Diag(OldParam->getLocation(), diag::err_previous_definition); 202 } else if (OldParam->getDefaultArg()) { 203 // Merge the old default argument into the new parameter 204 NewParam->setDefaultArg(OldParam->getDefaultArg()); 205 } 206 } 207 208 return New; 209} 210 211/// CheckCXXDefaultArguments - Verify that the default arguments for a 212/// function declaration are well-formed according to C++ 213/// [dcl.fct.default]. 214void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) { 215 unsigned NumParams = FD->getNumParams(); 216 unsigned p; 217 218 // Find first parameter with a default argument 219 for (p = 0; p < NumParams; ++p) { 220 ParmVarDecl *Param = FD->getParamDecl(p); 221 if (Param->getDefaultArg()) 222 break; 223 } 224 225 // C++ [dcl.fct.default]p4: 226 // In a given function declaration, all parameters 227 // subsequent to a parameter with a default argument shall 228 // have default arguments supplied in this or previous 229 // declarations. A default argument shall not be redefined 230 // by a later declaration (not even to the same value). 231 unsigned LastMissingDefaultArg = 0; 232 for(; p < NumParams; ++p) { 233 ParmVarDecl *Param = FD->getParamDecl(p); 234 if (!Param->getDefaultArg()) { 235 if (Param->getIdentifier()) 236 Diag(Param->getLocation(), 237 diag::err_param_default_argument_missing_name, 238 Param->getIdentifier()->getName()); 239 else 240 Diag(Param->getLocation(), 241 diag::err_param_default_argument_missing); 242 243 LastMissingDefaultArg = p; 244 } 245 } 246 247 if (LastMissingDefaultArg > 0) { 248 // Some default arguments were missing. Clear out all of the 249 // default arguments up to (and including) the last missing 250 // default argument, so that we leave the function parameters 251 // in a semantically valid state. 252 for (p = 0; p <= LastMissingDefaultArg; ++p) { 253 ParmVarDecl *Param = FD->getParamDecl(p); 254 if (Param->getDefaultArg()) { 255 delete Param->getDefaultArg(); 256 Param->setDefaultArg(0); 257 } 258 } 259 } 260} 261 262/// isCurrentClassName - Determine whether the identifier II is the 263/// name of the class type currently being defined. In the case of 264/// nested classes, this will only return true if II is the name of 265/// the innermost class. 266bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *, 267 const CXXScopeSpec *SS) { 268 CXXRecordDecl *CurDecl; 269 if (SS) { 270 DeclContext *DC = static_cast<DeclContext*>(SS->getScopeRep()); 271 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC); 272 } else 273 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 274 275 if (CurDecl) 276 return &II == CurDecl->getIdentifier(); 277 else 278 return false; 279} 280 281/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is 282/// one entry in the base class list of a class specifier, for 283/// example: 284/// class foo : public bar, virtual private baz { 285/// 'public bar' and 'virtual private baz' are each base-specifiers. 286Sema::BaseResult 287Sema::ActOnBaseSpecifier(DeclTy *classdecl, SourceRange SpecifierRange, 288 bool Virtual, AccessSpecifier Access, 289 TypeTy *basetype, SourceLocation BaseLoc) { 290 RecordDecl *Decl = (RecordDecl*)classdecl; 291 QualType BaseType = Context.getTypeDeclType((TypeDecl*)basetype); 292 293 // Base specifiers must be record types. 294 if (!BaseType->isRecordType()) { 295 Diag(BaseLoc, diag::err_base_must_be_class, SpecifierRange); 296 return true; 297 } 298 299 // C++ [class.union]p1: 300 // A union shall not be used as a base class. 301 if (BaseType->isUnionType()) { 302 Diag(BaseLoc, diag::err_union_as_base_class, SpecifierRange); 303 return true; 304 } 305 306 // C++ [class.union]p1: 307 // A union shall not have base classes. 308 if (Decl->isUnion()) { 309 Diag(Decl->getLocation(), diag::err_base_clause_on_union, 310 SpecifierRange); 311 return true; 312 } 313 314 // C++ [class.derived]p2: 315 // The class-name in a base-specifier shall not be an incompletely 316 // defined class. 317 if (BaseType->isIncompleteType()) { 318 Diag(BaseLoc, diag::err_incomplete_base_class, SpecifierRange); 319 return true; 320 } 321 322 // If the base class is polymorphic, the new one is, too. 323 RecordDecl *BaseDecl = BaseType->getAsRecordType()->getDecl(); 324 assert(BaseDecl && "Record type has no declaration"); 325 BaseDecl = BaseDecl->getDefinition(Context); 326 assert(BaseDecl && "Base type is not incomplete, but has no definition"); 327 if (cast<CXXRecordDecl>(BaseDecl)->isPolymorphic()) { 328 cast<CXXRecordDecl>(Decl)->setPolymorphic(true); 329 } 330 331 // Create the base specifier. 332 return new CXXBaseSpecifier(SpecifierRange, Virtual, 333 BaseType->isClassType(), Access, BaseType); 334} 335 336/// ActOnBaseSpecifiers - Attach the given base specifiers to the 337/// class, after checking whether there are any duplicate base 338/// classes. 339void Sema::ActOnBaseSpecifiers(DeclTy *ClassDecl, BaseTy **Bases, 340 unsigned NumBases) { 341 if (NumBases == 0) 342 return; 343 344 // Used to keep track of which base types we have already seen, so 345 // that we can properly diagnose redundant direct base types. Note 346 // that the key is always the unqualified canonical type of the base 347 // class. 348 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes; 349 350 // Copy non-redundant base specifiers into permanent storage. 351 CXXBaseSpecifier **BaseSpecs = (CXXBaseSpecifier **)Bases; 352 unsigned NumGoodBases = 0; 353 for (unsigned idx = 0; idx < NumBases; ++idx) { 354 QualType NewBaseType 355 = Context.getCanonicalType(BaseSpecs[idx]->getType()); 356 NewBaseType = NewBaseType.getUnqualifiedType(); 357 358 if (KnownBaseTypes[NewBaseType]) { 359 // C++ [class.mi]p3: 360 // A class shall not be specified as a direct base class of a 361 // derived class more than once. 362 Diag(BaseSpecs[idx]->getSourceRange().getBegin(), 363 diag::err_duplicate_base_class, 364 KnownBaseTypes[NewBaseType]->getType().getAsString(), 365 BaseSpecs[idx]->getSourceRange()); 366 367 // Delete the duplicate base class specifier; we're going to 368 // overwrite its pointer later. 369 delete BaseSpecs[idx]; 370 } else { 371 // Okay, add this new base class. 372 KnownBaseTypes[NewBaseType] = BaseSpecs[idx]; 373 BaseSpecs[NumGoodBases++] = BaseSpecs[idx]; 374 } 375 } 376 377 // Attach the remaining base class specifiers to the derived class. 378 CXXRecordDecl *Decl = (CXXRecordDecl*)ClassDecl; 379 Decl->setBases(BaseSpecs, NumGoodBases); 380 381 // Delete the remaining (good) base class specifiers, since their 382 // data has been copied into the CXXRecordDecl. 383 for (unsigned idx = 0; idx < NumGoodBases; ++idx) 384 delete BaseSpecs[idx]; 385} 386 387//===----------------------------------------------------------------------===// 388// C++ class member Handling 389//===----------------------------------------------------------------------===// 390 391/// ActOnStartCXXClassDef - This is called at the start of a class/struct/union 392/// definition, when on C++. 393void Sema::ActOnStartCXXClassDef(Scope *S, DeclTy *D, SourceLocation LBrace) { 394 CXXRecordDecl *Dcl = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 395 PushDeclContext(Dcl); 396 FieldCollector->StartClass(); 397 398 if (Dcl->getIdentifier()) { 399 // C++ [class]p2: 400 // [...] The class-name is also inserted into the scope of the 401 // class itself; this is known as the injected-class-name. For 402 // purposes of access checking, the injected-class-name is treated 403 // as if it were a public member name. 404 PushOnScopeChains(Dcl, S); 405 } 406} 407 408/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member 409/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the 410/// bitfield width if there is one and 'InitExpr' specifies the initializer if 411/// any. 'LastInGroup' is non-null for cases where one declspec has multiple 412/// declarators on it. 413/// 414/// NOTE: Because of CXXFieldDecl's inability to be chained like ScopedDecls, if 415/// an instance field is declared, a new CXXFieldDecl is created but the method 416/// does *not* return it; it returns LastInGroup instead. The other C++ members 417/// (which are all ScopedDecls) are returned after appending them to 418/// LastInGroup. 419Sema::DeclTy * 420Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D, 421 ExprTy *BW, ExprTy *InitExpr, 422 DeclTy *LastInGroup) { 423 const DeclSpec &DS = D.getDeclSpec(); 424 DeclarationName Name = GetNameForDeclarator(D); 425 Expr *BitWidth = static_cast<Expr*>(BW); 426 Expr *Init = static_cast<Expr*>(InitExpr); 427 SourceLocation Loc = D.getIdentifierLoc(); 428 429 bool isFunc = D.isFunctionDeclarator(); 430 431 // C++ 9.2p6: A member shall not be declared to have automatic storage 432 // duration (auto, register) or with the extern storage-class-specifier. 433 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class 434 // data members and cannot be applied to names declared const or static, 435 // and cannot be applied to reference members. 436 switch (DS.getStorageClassSpec()) { 437 case DeclSpec::SCS_unspecified: 438 case DeclSpec::SCS_typedef: 439 case DeclSpec::SCS_static: 440 // FALL THROUGH. 441 break; 442 case DeclSpec::SCS_mutable: 443 if (isFunc) { 444 if (DS.getStorageClassSpecLoc().isValid()) 445 Diag(DS.getStorageClassSpecLoc(), 446 diag::err_mutable_function); 447 else 448 Diag(DS.getThreadSpecLoc(), 449 diag::err_mutable_function); 450 D.getMutableDeclSpec().ClearStorageClassSpecs(); 451 } else { 452 QualType T = GetTypeForDeclarator(D, S); 453 diag::kind err = static_cast<diag::kind>(0); 454 if (T->isReferenceType()) 455 err = diag::err_mutable_reference; 456 else if (T.isConstQualified()) 457 err = diag::err_mutable_const; 458 if (err != 0) { 459 if (DS.getStorageClassSpecLoc().isValid()) 460 Diag(DS.getStorageClassSpecLoc(), err); 461 else 462 Diag(DS.getThreadSpecLoc(), err); 463 D.getMutableDeclSpec().ClearStorageClassSpecs(); 464 } 465 } 466 break; 467 default: 468 if (DS.getStorageClassSpecLoc().isValid()) 469 Diag(DS.getStorageClassSpecLoc(), 470 diag::err_storageclass_invalid_for_member); 471 else 472 Diag(DS.getThreadSpecLoc(), diag::err_storageclass_invalid_for_member); 473 D.getMutableDeclSpec().ClearStorageClassSpecs(); 474 } 475 476 if (!isFunc && 477 D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_typedef && 478 D.getNumTypeObjects() == 0) { 479 // Check also for this case: 480 // 481 // typedef int f(); 482 // f a; 483 // 484 Decl *TD = static_cast<Decl *>(DS.getTypeRep()); 485 isFunc = Context.getTypeDeclType(cast<TypeDecl>(TD))->isFunctionType(); 486 } 487 488 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified || 489 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) && 490 !isFunc); 491 492 Decl *Member; 493 bool InvalidDecl = false; 494 495 if (isInstField) 496 Member = static_cast<Decl*>(ActOnField(S, Loc, D, BitWidth)); 497 else 498 Member = static_cast<Decl*>(ActOnDeclarator(S, D, LastInGroup)); 499 500 if (!Member) return LastInGroup; 501 502 assert((Name || isInstField) && "No identifier for non-field ?"); 503 504 // set/getAccess is not part of Decl's interface to avoid bloating it with C++ 505 // specific methods. Use a wrapper class that can be used with all C++ class 506 // member decls. 507 CXXClassMemberWrapper(Member).setAccess(AS); 508 509 // C++ [dcl.init.aggr]p1: 510 // An aggregate is an array or a class (clause 9) with [...] no 511 // private or protected non-static data members (clause 11). 512 if (isInstField && (AS == AS_private || AS == AS_protected)) 513 cast<CXXRecordDecl>(CurContext)->setAggregate(false); 514 515 if (DS.isVirtualSpecified()) { 516 if (!isFunc || DS.getStorageClassSpec() == DeclSpec::SCS_static) { 517 Diag(DS.getVirtualSpecLoc(), diag::err_virtual_non_function); 518 InvalidDecl = true; 519 } else { 520 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(CurContext); 521 CurClass->setAggregate(false); 522 CurClass->setPolymorphic(true); 523 } 524 } 525 526 if (BitWidth) { 527 // C++ 9.6p2: Only when declaring an unnamed bit-field may the 528 // constant-expression be a value equal to zero. 529 // FIXME: Check this. 530 531 if (D.isFunctionDeclarator()) { 532 // FIXME: Emit diagnostic about only constructors taking base initializers 533 // or something similar, when constructor support is in place. 534 Diag(Loc, diag::err_not_bitfield_type, 535 Name.getAsString(), BitWidth->getSourceRange()); 536 InvalidDecl = true; 537 538 } else if (isInstField) { 539 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 540 if (!cast<FieldDecl>(Member)->getType()->isIntegralType()) { 541 Diag(Loc, diag::err_not_integral_type_bitfield, 542 Name.getAsString(), BitWidth->getSourceRange()); 543 InvalidDecl = true; 544 } 545 546 } else if (isa<FunctionDecl>(Member)) { 547 // A function typedef ("typedef int f(); f a;"). 548 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 549 Diag(Loc, diag::err_not_integral_type_bitfield, 550 Name.getAsString(), BitWidth->getSourceRange()); 551 InvalidDecl = true; 552 553 } else if (isa<TypedefDecl>(Member)) { 554 // "cannot declare 'A' to be a bit-field type" 555 Diag(Loc, diag::err_not_bitfield_type, Name.getAsString(), 556 BitWidth->getSourceRange()); 557 InvalidDecl = true; 558 559 } else { 560 assert(isa<CXXClassVarDecl>(Member) && 561 "Didn't we cover all member kinds?"); 562 // C++ 9.6p3: A bit-field shall not be a static member. 563 // "static member 'A' cannot be a bit-field" 564 Diag(Loc, diag::err_static_not_bitfield, Name.getAsString(), 565 BitWidth->getSourceRange()); 566 InvalidDecl = true; 567 } 568 } 569 570 if (Init) { 571 // C++ 9.2p4: A member-declarator can contain a constant-initializer only 572 // if it declares a static member of const integral or const enumeration 573 // type. 574 if (CXXClassVarDecl *CVD = dyn_cast<CXXClassVarDecl>(Member)) { 575 // ...static member of... 576 CVD->setInit(Init); 577 // ...const integral or const enumeration type. 578 if (Context.getCanonicalType(CVD->getType()).isConstQualified() && 579 CVD->getType()->isIntegralType()) { 580 // constant-initializer 581 if (CheckForConstantInitializer(Init, CVD->getType())) 582 InvalidDecl = true; 583 584 } else { 585 // not const integral. 586 Diag(Loc, diag::err_member_initialization, 587 Name.getAsString(), Init->getSourceRange()); 588 InvalidDecl = true; 589 } 590 591 } else { 592 // not static member. 593 Diag(Loc, diag::err_member_initialization, 594 Name.getAsString(), Init->getSourceRange()); 595 InvalidDecl = true; 596 } 597 } 598 599 if (InvalidDecl) 600 Member->setInvalidDecl(); 601 602 if (isInstField) { 603 FieldCollector->Add(cast<CXXFieldDecl>(Member)); 604 return LastInGroup; 605 } 606 return Member; 607} 608 609/// ActOnMemInitializer - Handle a C++ member initializer. 610Sema::MemInitResult 611Sema::ActOnMemInitializer(DeclTy *ConstructorD, 612 Scope *S, 613 IdentifierInfo *MemberOrBase, 614 SourceLocation IdLoc, 615 SourceLocation LParenLoc, 616 ExprTy **Args, unsigned NumArgs, 617 SourceLocation *CommaLocs, 618 SourceLocation RParenLoc) { 619 CXXConstructorDecl *Constructor 620 = dyn_cast<CXXConstructorDecl>((Decl*)ConstructorD); 621 if (!Constructor) { 622 // The user wrote a constructor initializer on a function that is 623 // not a C++ constructor. Ignore the error for now, because we may 624 // have more member initializers coming; we'll diagnose it just 625 // once in ActOnMemInitializers. 626 return true; 627 } 628 629 CXXRecordDecl *ClassDecl = Constructor->getParent(); 630 631 // C++ [class.base.init]p2: 632 // Names in a mem-initializer-id are looked up in the scope of the 633 // constructor’s class and, if not found in that scope, are looked 634 // up in the scope containing the constructor’s 635 // definition. [Note: if the constructor’s class contains a member 636 // with the same name as a direct or virtual base class of the 637 // class, a mem-initializer-id naming the member or base class and 638 // composed of a single identifier refers to the class member. A 639 // mem-initializer-id for the hidden base class may be specified 640 // using a qualified name. ] 641 // Look for a member, first. 642 CXXFieldDecl *Member = ClassDecl->getMember(MemberOrBase); 643 644 // FIXME: Handle members of an anonymous union. 645 646 if (Member) { 647 // FIXME: Perform direct initialization of the member. 648 return new CXXBaseOrMemberInitializer(Member, (Expr **)Args, NumArgs); 649 } 650 651 // It didn't name a member, so see if it names a class. 652 TypeTy *BaseTy = isTypeName(*MemberOrBase, S, 0/*SS*/); 653 if (!BaseTy) 654 return Diag(IdLoc, diag::err_mem_init_not_member_or_class, 655 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 656 657 QualType BaseType = Context.getTypeDeclType((TypeDecl *)BaseTy); 658 if (!BaseType->isRecordType()) 659 return Diag(IdLoc, diag::err_base_init_does_not_name_class, 660 BaseType.getAsString(), SourceRange(IdLoc, RParenLoc)); 661 662 // C++ [class.base.init]p2: 663 // [...] Unless the mem-initializer-id names a nonstatic data 664 // member of the constructor’s class or a direct or virtual base 665 // of that class, the mem-initializer is ill-formed. A 666 // mem-initializer-list can initialize a base class using any 667 // name that denotes that base class type. 668 669 // First, check for a direct base class. 670 const CXXBaseSpecifier *DirectBaseSpec = 0; 671 for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin(); 672 Base != ClassDecl->bases_end(); ++Base) { 673 if (Context.getCanonicalType(BaseType).getUnqualifiedType() == 674 Context.getCanonicalType(Base->getType()).getUnqualifiedType()) { 675 // We found a direct base of this type. That's what we're 676 // initializing. 677 DirectBaseSpec = &*Base; 678 break; 679 } 680 } 681 682 // Check for a virtual base class. 683 // FIXME: We might be able to short-circuit this if we know in 684 // advance that there are no virtual bases. 685 const CXXBaseSpecifier *VirtualBaseSpec = 0; 686 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) { 687 // We haven't found a base yet; search the class hierarchy for a 688 // virtual base class. 689 BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 690 /*DetectVirtual=*/false); 691 if (IsDerivedFrom(Context.getTypeDeclType(ClassDecl), BaseType, Paths)) { 692 for (BasePaths::paths_iterator Path = Paths.begin(); 693 Path != Paths.end(); ++Path) { 694 if (Path->back().Base->isVirtual()) { 695 VirtualBaseSpec = Path->back().Base; 696 break; 697 } 698 } 699 } 700 } 701 702 // C++ [base.class.init]p2: 703 // If a mem-initializer-id is ambiguous because it designates both 704 // a direct non-virtual base class and an inherited virtual base 705 // class, the mem-initializer is ill-formed. 706 if (DirectBaseSpec && VirtualBaseSpec) 707 return Diag(IdLoc, diag::err_base_init_direct_and_virtual, 708 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 709 710 return new CXXBaseOrMemberInitializer(BaseType, (Expr **)Args, NumArgs); 711} 712 713 714void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc, 715 DeclTy *TagDecl, 716 SourceLocation LBrac, 717 SourceLocation RBrac) { 718 ActOnFields(S, RLoc, TagDecl, 719 (DeclTy**)FieldCollector->getCurFields(), 720 FieldCollector->getCurNumFields(), LBrac, RBrac, 0); 721} 722 723/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared 724/// special functions, such as the default constructor, copy 725/// constructor, or destructor, to the given C++ class (C++ 726/// [special]p1). This routine can only be executed just before the 727/// definition of the class is complete. 728void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) { 729 QualType ClassType = Context.getTypeDeclType(ClassDecl); 730 ClassType = Context.getCanonicalType(ClassType); 731 732 if (!ClassDecl->hasUserDeclaredConstructor()) { 733 // C++ [class.ctor]p5: 734 // A default constructor for a class X is a constructor of class X 735 // that can be called without an argument. If there is no 736 // user-declared constructor for class X, a default constructor is 737 // implicitly declared. An implicitly-declared default constructor 738 // is an inline public member of its class. 739 DeclarationName Name 740 = Context.DeclarationNames.getCXXConstructorName(ClassType); 741 CXXConstructorDecl *DefaultCon = 742 CXXConstructorDecl::Create(Context, ClassDecl, 743 ClassDecl->getLocation(), Name, 744 Context.getFunctionType(Context.VoidTy, 745 0, 0, false, 0), 746 /*isExplicit=*/false, 747 /*isInline=*/true, 748 /*isImplicitlyDeclared=*/true); 749 DefaultCon->setAccess(AS_public); 750 ClassDecl->addConstructor(Context, DefaultCon); 751 } 752 753 if (!ClassDecl->hasUserDeclaredCopyConstructor()) { 754 // C++ [class.copy]p4: 755 // If the class definition does not explicitly declare a copy 756 // constructor, one is declared implicitly. 757 758 // C++ [class.copy]p5: 759 // The implicitly-declared copy constructor for a class X will 760 // have the form 761 // 762 // X::X(const X&) 763 // 764 // if 765 bool HasConstCopyConstructor = true; 766 767 // -- each direct or virtual base class B of X has a copy 768 // constructor whose first parameter is of type const B& or 769 // const volatile B&, and 770 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 771 HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { 772 const CXXRecordDecl *BaseClassDecl 773 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 774 HasConstCopyConstructor 775 = BaseClassDecl->hasConstCopyConstructor(Context); 776 } 777 778 // -- for all the nonstatic data members of X that are of a 779 // class type M (or array thereof), each such class type 780 // has a copy constructor whose first parameter is of type 781 // const M& or const volatile M&. 782 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(); 783 HasConstCopyConstructor && Field != ClassDecl->field_end(); ++Field) { 784 QualType FieldType = (*Field)->getType(); 785 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 786 FieldType = Array->getElementType(); 787 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 788 const CXXRecordDecl *FieldClassDecl 789 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 790 HasConstCopyConstructor 791 = FieldClassDecl->hasConstCopyConstructor(Context); 792 } 793 } 794 795 // Otherwise, the implicitly declared copy constructor will have 796 // the form 797 // 798 // X::X(X&) 799 QualType ArgType = Context.getTypeDeclType(ClassDecl); 800 if (HasConstCopyConstructor) 801 ArgType = ArgType.withConst(); 802 ArgType = Context.getReferenceType(ArgType); 803 804 // An implicitly-declared copy constructor is an inline public 805 // member of its class. 806 DeclarationName Name 807 = Context.DeclarationNames.getCXXConstructorName(ClassType); 808 CXXConstructorDecl *CopyConstructor 809 = CXXConstructorDecl::Create(Context, ClassDecl, 810 ClassDecl->getLocation(), Name, 811 Context.getFunctionType(Context.VoidTy, 812 &ArgType, 1, 813 false, 0), 814 /*isExplicit=*/false, 815 /*isInline=*/true, 816 /*isImplicitlyDeclared=*/true); 817 CopyConstructor->setAccess(AS_public); 818 819 // Add the parameter to the constructor. 820 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, 821 ClassDecl->getLocation(), 822 /*IdentifierInfo=*/0, 823 ArgType, VarDecl::None, 0, 0); 824 CopyConstructor->setParams(&FromParam, 1); 825 826 ClassDecl->addConstructor(Context, CopyConstructor); 827 } 828 829 if (!ClassDecl->getDestructor()) { 830 // C++ [class.dtor]p2: 831 // If a class has no user-declared destructor, a destructor is 832 // declared implicitly. An implicitly-declared destructor is an 833 // inline public member of its class. 834 DeclarationName Name 835 = Context.DeclarationNames.getCXXDestructorName(ClassType); 836 CXXDestructorDecl *Destructor 837 = CXXDestructorDecl::Create(Context, ClassDecl, 838 ClassDecl->getLocation(), Name, 839 Context.getFunctionType(Context.VoidTy, 840 0, 0, false, 0), 841 /*isInline=*/true, 842 /*isImplicitlyDeclared=*/true); 843 Destructor->setAccess(AS_public); 844 ClassDecl->setDestructor(Destructor); 845 } 846 847 // FIXME: Implicit copy assignment operator 848} 849 850void Sema::ActOnFinishCXXClassDef(DeclTy *D) { 851 CXXRecordDecl *Rec = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 852 FieldCollector->FinishClass(); 853 AddImplicitlyDeclaredMembersToClass(Rec); 854 PopDeclContext(); 855 856 // Everything, including inline method definitions, have been parsed. 857 // Let the consumer know of the new TagDecl definition. 858 Consumer.HandleTagDeclDefinition(Rec); 859} 860 861/// CheckConstructorDeclarator - Called by ActOnDeclarator to check 862/// the well-formednes of the constructor declarator @p D with type @p 863/// R. If there are any errors in the declarator, this routine will 864/// emit diagnostics and return true. Otherwise, it will return 865/// false. Either way, the type @p R will be updated to reflect a 866/// well-formed type for the constructor. 867bool Sema::CheckConstructorDeclarator(Declarator &D, QualType &R, 868 FunctionDecl::StorageClass& SC) { 869 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 870 bool isInvalid = false; 871 872 // C++ [class.ctor]p3: 873 // A constructor shall not be virtual (10.3) or static (9.4). A 874 // constructor can be invoked for a const, volatile or const 875 // volatile object. A constructor shall not be declared const, 876 // volatile, or const volatile (9.3.2). 877 if (isVirtual) { 878 Diag(D.getIdentifierLoc(), 879 diag::err_constructor_cannot_be, 880 "virtual", 881 SourceRange(D.getDeclSpec().getVirtualSpecLoc()), 882 SourceRange(D.getIdentifierLoc())); 883 isInvalid = true; 884 } 885 if (SC == FunctionDecl::Static) { 886 Diag(D.getIdentifierLoc(), 887 diag::err_constructor_cannot_be, 888 "static", 889 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 890 SourceRange(D.getIdentifierLoc())); 891 isInvalid = true; 892 SC = FunctionDecl::None; 893 } 894 if (D.getDeclSpec().hasTypeSpecifier()) { 895 // Constructors don't have return types, but the parser will 896 // happily parse something like: 897 // 898 // class X { 899 // float X(float); 900 // }; 901 // 902 // The return type will be eliminated later. 903 Diag(D.getIdentifierLoc(), 904 diag::err_constructor_return_type, 905 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 906 SourceRange(D.getIdentifierLoc())); 907 } 908 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 909 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 910 if (FTI.TypeQuals & QualType::Const) 911 Diag(D.getIdentifierLoc(), 912 diag::err_invalid_qualified_constructor, 913 "const", 914 SourceRange(D.getIdentifierLoc())); 915 if (FTI.TypeQuals & QualType::Volatile) 916 Diag(D.getIdentifierLoc(), 917 diag::err_invalid_qualified_constructor, 918 "volatile", 919 SourceRange(D.getIdentifierLoc())); 920 if (FTI.TypeQuals & QualType::Restrict) 921 Diag(D.getIdentifierLoc(), 922 diag::err_invalid_qualified_constructor, 923 "restrict", 924 SourceRange(D.getIdentifierLoc())); 925 } 926 927 // Rebuild the function type "R" without any type qualifiers (in 928 // case any of the errors above fired) and with "void" as the 929 // return type, since constructors don't have return types. We 930 // *always* have to do this, because GetTypeForDeclarator will 931 // put in a result type of "int" when none was specified. 932 const FunctionTypeProto *Proto = R->getAsFunctionTypeProto(); 933 R = Context.getFunctionType(Context.VoidTy, Proto->arg_type_begin(), 934 Proto->getNumArgs(), 935 Proto->isVariadic(), 936 0); 937 938 return isInvalid; 939} 940 941/// CheckDestructorDeclarator - Called by ActOnDeclarator to check 942/// the well-formednes of the destructor declarator @p D with type @p 943/// R. If there are any errors in the declarator, this routine will 944/// emit diagnostics and return true. Otherwise, it will return 945/// false. Either way, the type @p R will be updated to reflect a 946/// well-formed type for the destructor. 947bool Sema::CheckDestructorDeclarator(Declarator &D, QualType &R, 948 FunctionDecl::StorageClass& SC) { 949 bool isInvalid = false; 950 951 // C++ [class.dtor]p1: 952 // [...] A typedef-name that names a class is a class-name 953 // (7.1.3); however, a typedef-name that names a class shall not 954 // be used as the identifier in the declarator for a destructor 955 // declaration. 956 TypeDecl *DeclaratorTypeD = (TypeDecl *)D.getDeclaratorIdType(); 957 if (const TypedefDecl *TypedefD = dyn_cast<TypedefDecl>(DeclaratorTypeD)) { 958 Diag(D.getIdentifierLoc(), 959 diag::err_destructor_typedef_name, 960 TypedefD->getName()); 961 isInvalid = true; 962 } 963 964 // C++ [class.dtor]p2: 965 // A destructor is used to destroy objects of its class type. A 966 // destructor takes no parameters, and no return type can be 967 // specified for it (not even void). The address of a destructor 968 // shall not be taken. A destructor shall not be static. A 969 // destructor can be invoked for a const, volatile or const 970 // volatile object. A destructor shall not be declared const, 971 // volatile or const volatile (9.3.2). 972 if (SC == FunctionDecl::Static) { 973 Diag(D.getIdentifierLoc(), 974 diag::err_destructor_cannot_be, 975 "static", 976 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 977 SourceRange(D.getIdentifierLoc())); 978 isInvalid = true; 979 SC = FunctionDecl::None; 980 } 981 if (D.getDeclSpec().hasTypeSpecifier()) { 982 // Destructors don't have return types, but the parser will 983 // happily parse something like: 984 // 985 // class X { 986 // float ~X(); 987 // }; 988 // 989 // The return type will be eliminated later. 990 Diag(D.getIdentifierLoc(), 991 diag::err_destructor_return_type, 992 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 993 SourceRange(D.getIdentifierLoc())); 994 } 995 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 996 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 997 if (FTI.TypeQuals & QualType::Const) 998 Diag(D.getIdentifierLoc(), 999 diag::err_invalid_qualified_destructor, 1000 "const", 1001 SourceRange(D.getIdentifierLoc())); 1002 if (FTI.TypeQuals & QualType::Volatile) 1003 Diag(D.getIdentifierLoc(), 1004 diag::err_invalid_qualified_destructor, 1005 "volatile", 1006 SourceRange(D.getIdentifierLoc())); 1007 if (FTI.TypeQuals & QualType::Restrict) 1008 Diag(D.getIdentifierLoc(), 1009 diag::err_invalid_qualified_destructor, 1010 "restrict", 1011 SourceRange(D.getIdentifierLoc())); 1012 } 1013 1014 // Make sure we don't have any parameters. 1015 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 1016 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params); 1017 1018 // Delete the parameters. 1019 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1020 if (FTI.NumArgs) { 1021 delete [] FTI.ArgInfo; 1022 FTI.NumArgs = 0; 1023 FTI.ArgInfo = 0; 1024 } 1025 } 1026 1027 // Make sure the destructor isn't variadic. 1028 if (R->getAsFunctionTypeProto()->isVariadic()) 1029 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic); 1030 1031 // Rebuild the function type "R" without any type qualifiers or 1032 // parameters (in case any of the errors above fired) and with 1033 // "void" as the return type, since destructors don't have return 1034 // types. We *always* have to do this, because GetTypeForDeclarator 1035 // will put in a result type of "int" when none was specified. 1036 R = Context.getFunctionType(Context.VoidTy, 0, 0, false, 0); 1037 1038 return isInvalid; 1039} 1040 1041/// CheckConversionDeclarator - Called by ActOnDeclarator to check the 1042/// well-formednes of the conversion function declarator @p D with 1043/// type @p R. If there are any errors in the declarator, this routine 1044/// will emit diagnostics and return true. Otherwise, it will return 1045/// false. Either way, the type @p R will be updated to reflect a 1046/// well-formed type for the conversion operator. 1047bool Sema::CheckConversionDeclarator(Declarator &D, QualType &R, 1048 FunctionDecl::StorageClass& SC) { 1049 bool isInvalid = false; 1050 1051 // C++ [class.conv.fct]p1: 1052 // Neither parameter types nor return type can be specified. The 1053 // type of a conversion function (8.3.5) is “function taking no 1054 // parameter returning conversion-type-id.” 1055 if (SC == FunctionDecl::Static) { 1056 Diag(D.getIdentifierLoc(), 1057 diag::err_conv_function_not_member, 1058 "static", 1059 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 1060 SourceRange(D.getIdentifierLoc())); 1061 isInvalid = true; 1062 SC = FunctionDecl::None; 1063 } 1064 if (D.getDeclSpec().hasTypeSpecifier()) { 1065 // Conversion functions don't have return types, but the parser will 1066 // happily parse something like: 1067 // 1068 // class X { 1069 // float operator bool(); 1070 // }; 1071 // 1072 // The return type will be changed later anyway. 1073 Diag(D.getIdentifierLoc(), 1074 diag::err_conv_function_return_type, 1075 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 1076 SourceRange(D.getIdentifierLoc())); 1077 } 1078 1079 // Make sure we don't have any parameters. 1080 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 1081 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params); 1082 1083 // Delete the parameters. 1084 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1085 if (FTI.NumArgs) { 1086 delete [] FTI.ArgInfo; 1087 FTI.NumArgs = 0; 1088 FTI.ArgInfo = 0; 1089 } 1090 } 1091 1092 // Make sure the conversion function isn't variadic. 1093 if (R->getAsFunctionTypeProto()->isVariadic()) 1094 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic); 1095 1096 // C++ [class.conv.fct]p4: 1097 // The conversion-type-id shall not represent a function type nor 1098 // an array type. 1099 QualType ConvType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1100 if (ConvType->isArrayType()) { 1101 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array); 1102 ConvType = Context.getPointerType(ConvType); 1103 } else if (ConvType->isFunctionType()) { 1104 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function); 1105 ConvType = Context.getPointerType(ConvType); 1106 } 1107 1108 // Rebuild the function type "R" without any parameters (in case any 1109 // of the errors above fired) and with the conversion type as the 1110 // return type. 1111 R = Context.getFunctionType(ConvType, 0, 0, false, 1112 R->getAsFunctionTypeProto()->getTypeQuals()); 1113 1114 return isInvalid; 1115} 1116 1117/// ActOnConstructorDeclarator - Called by ActOnDeclarator to complete 1118/// the declaration of the given C++ constructor ConDecl that was 1119/// built from declarator D. This routine is responsible for checking 1120/// that the newly-created constructor declaration is well-formed and 1121/// for recording it in the C++ class. Example: 1122/// 1123/// @code 1124/// class X { 1125/// X(); // X::X() will be the ConDecl. 1126/// }; 1127/// @endcode 1128Sema::DeclTy *Sema::ActOnConstructorDeclarator(CXXConstructorDecl *ConDecl) { 1129 assert(ConDecl && "Expected to receive a constructor declaration"); 1130 1131 // Check default arguments on the constructor 1132 CheckCXXDefaultArguments(ConDecl); 1133 1134 CXXRecordDecl *ClassDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 1135 if (!ClassDecl) { 1136 ConDecl->setInvalidDecl(); 1137 return ConDecl; 1138 } 1139 1140 // Make sure this constructor is an overload of the existing 1141 // constructors. 1142 OverloadedFunctionDecl::function_iterator MatchedDecl; 1143 if (!IsOverload(ConDecl, ClassDecl->getConstructors(), MatchedDecl)) { 1144 Diag(ConDecl->getLocation(), 1145 diag::err_constructor_redeclared, 1146 SourceRange(ConDecl->getLocation())); 1147 Diag((*MatchedDecl)->getLocation(), 1148 diag::err_previous_declaration, 1149 SourceRange((*MatchedDecl)->getLocation())); 1150 ConDecl->setInvalidDecl(); 1151 return ConDecl; 1152 } 1153 1154 1155 // C++ [class.copy]p3: 1156 // A declaration of a constructor for a class X is ill-formed if 1157 // its first parameter is of type (optionally cv-qualified) X and 1158 // either there are no other parameters or else all other 1159 // parameters have default arguments. 1160 if ((ConDecl->getNumParams() == 1) || 1161 (ConDecl->getNumParams() > 1 && 1162 ConDecl->getParamDecl(1)->getDefaultArg() != 0)) { 1163 QualType ParamType = ConDecl->getParamDecl(0)->getType(); 1164 QualType ClassTy = Context.getTagDeclType( 1165 const_cast<CXXRecordDecl*>(ConDecl->getParent())); 1166 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { 1167 Diag(ConDecl->getLocation(), 1168 diag::err_constructor_byvalue_arg, 1169 SourceRange(ConDecl->getParamDecl(0)->getLocation())); 1170 ConDecl->setInvalidDecl(); 1171 return ConDecl; 1172 } 1173 } 1174 1175 // Add this constructor to the set of constructors of the current 1176 // class. 1177 ClassDecl->addConstructor(Context, ConDecl); 1178 return (DeclTy *)ConDecl; 1179} 1180 1181/// ActOnDestructorDeclarator - Called by ActOnDeclarator to complete 1182/// the declaration of the given C++ @p Destructor. This routine is 1183/// responsible for recording the destructor in the C++ class, if 1184/// possible. 1185Sema::DeclTy *Sema::ActOnDestructorDeclarator(CXXDestructorDecl *Destructor) { 1186 assert(Destructor && "Expected to receive a destructor declaration"); 1187 1188 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1189 1190 // Make sure we aren't redeclaring the destructor. 1191 if (CXXDestructorDecl *PrevDestructor = ClassDecl->getDestructor()) { 1192 Diag(Destructor->getLocation(), diag::err_destructor_redeclared); 1193 Diag(PrevDestructor->getLocation(), 1194 PrevDestructor->isThisDeclarationADefinition()? 1195 diag::err_previous_definition 1196 : diag::err_previous_declaration); 1197 Destructor->setInvalidDecl(); 1198 return Destructor; 1199 } 1200 1201 ClassDecl->setDestructor(Destructor); 1202 return (DeclTy *)Destructor; 1203} 1204 1205/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete 1206/// the declaration of the given C++ conversion function. This routine 1207/// is responsible for recording the conversion function in the C++ 1208/// class, if possible. 1209Sema::DeclTy *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) { 1210 assert(Conversion && "Expected to receive a conversion function declaration"); 1211 1212 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1213 1214 // Make sure we aren't redeclaring the conversion function. 1215 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType()); 1216 OverloadedFunctionDecl *Conversions = ClassDecl->getConversionFunctions(); 1217 for (OverloadedFunctionDecl::function_iterator Func 1218 = Conversions->function_begin(); 1219 Func != Conversions->function_end(); ++Func) { 1220 CXXConversionDecl *OtherConv = cast<CXXConversionDecl>(*Func); 1221 if (ConvType == Context.getCanonicalType(OtherConv->getConversionType())) { 1222 Diag(Conversion->getLocation(), diag::err_conv_function_redeclared); 1223 Diag(OtherConv->getLocation(), 1224 OtherConv->isThisDeclarationADefinition()? 1225 diag::err_previous_definition 1226 : diag::err_previous_declaration); 1227 Conversion->setInvalidDecl(); 1228 return (DeclTy *)Conversion; 1229 } 1230 } 1231 1232 // C++ [class.conv.fct]p1: 1233 // [...] A conversion function is never used to convert a 1234 // (possibly cv-qualified) object to the (possibly cv-qualified) 1235 // same object type (or a reference to it), to a (possibly 1236 // cv-qualified) base class of that type (or a reference to it), 1237 // or to (possibly cv-qualified) void. 1238 // FIXME: Suppress this warning if the conversion function ends up 1239 // being a virtual function that overrides a virtual function in a 1240 // base class. 1241 QualType ClassType 1242 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl)); 1243 if (const ReferenceType *ConvTypeRef = ConvType->getAsReferenceType()) 1244 ConvType = ConvTypeRef->getPointeeType(); 1245 if (ConvType->isRecordType()) { 1246 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType(); 1247 if (ConvType == ClassType) 1248 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used, 1249 ClassType.getAsString()); 1250 else if (IsDerivedFrom(ClassType, ConvType)) 1251 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used, 1252 ClassType.getAsString(), 1253 ConvType.getAsString()); 1254 } else if (ConvType->isVoidType()) { 1255 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used, 1256 ClassType.getAsString(), ConvType.getAsString()); 1257 } 1258 1259 ClassDecl->addConversionFunction(Context, Conversion); 1260 1261 return (DeclTy *)Conversion; 1262} 1263 1264//===----------------------------------------------------------------------===// 1265// Namespace Handling 1266//===----------------------------------------------------------------------===// 1267 1268/// ActOnStartNamespaceDef - This is called at the start of a namespace 1269/// definition. 1270Sema::DeclTy *Sema::ActOnStartNamespaceDef(Scope *NamespcScope, 1271 SourceLocation IdentLoc, 1272 IdentifierInfo *II, 1273 SourceLocation LBrace) { 1274 NamespaceDecl *Namespc = 1275 NamespaceDecl::Create(Context, CurContext, IdentLoc, II); 1276 Namespc->setLBracLoc(LBrace); 1277 1278 Scope *DeclRegionScope = NamespcScope->getParent(); 1279 1280 if (II) { 1281 // C++ [namespace.def]p2: 1282 // The identifier in an original-namespace-definition shall not have been 1283 // previously defined in the declarative region in which the 1284 // original-namespace-definition appears. The identifier in an 1285 // original-namespace-definition is the name of the namespace. Subsequently 1286 // in that declarative region, it is treated as an original-namespace-name. 1287 1288 Decl *PrevDecl = 1289 LookupDecl(II, Decl::IDNS_Tag | Decl::IDNS_Ordinary, DeclRegionScope, 0, 1290 /*enableLazyBuiltinCreation=*/false); 1291 1292 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, DeclRegionScope)) { 1293 if (NamespaceDecl *OrigNS = dyn_cast<NamespaceDecl>(PrevDecl)) { 1294 // This is an extended namespace definition. 1295 // Attach this namespace decl to the chain of extended namespace 1296 // definitions. 1297 NamespaceDecl *NextNS = OrigNS; 1298 while (NextNS->getNextNamespace()) 1299 NextNS = NextNS->getNextNamespace(); 1300 1301 NextNS->setNextNamespace(Namespc); 1302 Namespc->setOriginalNamespace(OrigNS); 1303 1304 // We won't add this decl to the current scope. We want the namespace 1305 // name to return the original namespace decl during a name lookup. 1306 } else { 1307 // This is an invalid name redefinition. 1308 Diag(Namespc->getLocation(), diag::err_redefinition_different_kind, 1309 Namespc->getName()); 1310 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1311 Namespc->setInvalidDecl(); 1312 // Continue on to push Namespc as current DeclContext and return it. 1313 } 1314 } else { 1315 // This namespace name is declared for the first time. 1316 PushOnScopeChains(Namespc, DeclRegionScope); 1317 } 1318 } 1319 else { 1320 // FIXME: Handle anonymous namespaces 1321 } 1322 1323 // Although we could have an invalid decl (i.e. the namespace name is a 1324 // redefinition), push it as current DeclContext and try to continue parsing. 1325 PushDeclContext(Namespc->getOriginalNamespace()); 1326 return Namespc; 1327} 1328 1329/// ActOnFinishNamespaceDef - This callback is called after a namespace is 1330/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. 1331void Sema::ActOnFinishNamespaceDef(DeclTy *D, SourceLocation RBrace) { 1332 Decl *Dcl = static_cast<Decl *>(D); 1333 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); 1334 assert(Namespc && "Invalid parameter, expected NamespaceDecl"); 1335 Namespc->setRBracLoc(RBrace); 1336 PopDeclContext(); 1337} 1338 1339 1340/// AddCXXDirectInitializerToDecl - This action is called immediately after 1341/// ActOnDeclarator, when a C++ direct initializer is present. 1342/// e.g: "int x(1);" 1343void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc, 1344 ExprTy **ExprTys, unsigned NumExprs, 1345 SourceLocation *CommaLocs, 1346 SourceLocation RParenLoc) { 1347 assert(NumExprs != 0 && ExprTys && "missing expressions"); 1348 Decl *RealDecl = static_cast<Decl *>(Dcl); 1349 1350 // If there is no declaration, there was an error parsing it. Just ignore 1351 // the initializer. 1352 if (RealDecl == 0) { 1353 for (unsigned i = 0; i != NumExprs; ++i) 1354 delete static_cast<Expr *>(ExprTys[i]); 1355 return; 1356 } 1357 1358 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1359 if (!VDecl) { 1360 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 1361 RealDecl->setInvalidDecl(); 1362 return; 1363 } 1364 1365 // We will treat direct-initialization as a copy-initialization: 1366 // int x(1); -as-> int x = 1; 1367 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); 1368 // 1369 // Clients that want to distinguish between the two forms, can check for 1370 // direct initializer using VarDecl::hasCXXDirectInitializer(). 1371 // A major benefit is that clients that don't particularly care about which 1372 // exactly form was it (like the CodeGen) can handle both cases without 1373 // special case code. 1374 1375 // C++ 8.5p11: 1376 // The form of initialization (using parentheses or '=') is generally 1377 // insignificant, but does matter when the entity being initialized has a 1378 // class type. 1379 QualType DeclInitType = VDecl->getType(); 1380 if (const ArrayType *Array = Context.getAsArrayType(DeclInitType)) 1381 DeclInitType = Array->getElementType(); 1382 1383 if (VDecl->getType()->isRecordType()) { 1384 CXXConstructorDecl *Constructor 1385 = PerformInitializationByConstructor(DeclInitType, 1386 (Expr **)ExprTys, NumExprs, 1387 VDecl->getLocation(), 1388 SourceRange(VDecl->getLocation(), 1389 RParenLoc), 1390 VDecl->getName(), 1391 IK_Direct); 1392 if (!Constructor) { 1393 RealDecl->setInvalidDecl(); 1394 } 1395 1396 // Let clients know that initialization was done with a direct 1397 // initializer. 1398 VDecl->setCXXDirectInitializer(true); 1399 1400 // FIXME: Add ExprTys and Constructor to the RealDecl as part of 1401 // the initializer. 1402 return; 1403 } 1404 1405 if (NumExprs > 1) { 1406 Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg, 1407 SourceRange(VDecl->getLocation(), RParenLoc)); 1408 RealDecl->setInvalidDecl(); 1409 return; 1410 } 1411 1412 // Let clients know that initialization was done with a direct initializer. 1413 VDecl->setCXXDirectInitializer(true); 1414 1415 assert(NumExprs == 1 && "Expected 1 expression"); 1416 // Set the init expression, handles conversions. 1417 AddInitializerToDecl(Dcl, ExprTys[0]); 1418} 1419 1420/// PerformInitializationByConstructor - Perform initialization by 1421/// constructor (C++ [dcl.init]p14), which may occur as part of 1422/// direct-initialization or copy-initialization. We are initializing 1423/// an object of type @p ClassType with the given arguments @p 1424/// Args. @p Loc is the location in the source code where the 1425/// initializer occurs (e.g., a declaration, member initializer, 1426/// functional cast, etc.) while @p Range covers the whole 1427/// initialization. @p InitEntity is the entity being initialized, 1428/// which may by the name of a declaration or a type. @p Kind is the 1429/// kind of initialization we're performing, which affects whether 1430/// explicit constructors will be considered. When successful, returns 1431/// the constructor that will be used to perform the initialization; 1432/// when the initialization fails, emits a diagnostic and returns 1433/// null. 1434CXXConstructorDecl * 1435Sema::PerformInitializationByConstructor(QualType ClassType, 1436 Expr **Args, unsigned NumArgs, 1437 SourceLocation Loc, SourceRange Range, 1438 std::string InitEntity, 1439 InitializationKind Kind) { 1440 const RecordType *ClassRec = ClassType->getAsRecordType(); 1441 assert(ClassRec && "Can only initialize a class type here"); 1442 1443 // C++ [dcl.init]p14: 1444 // 1445 // If the initialization is direct-initialization, or if it is 1446 // copy-initialization where the cv-unqualified version of the 1447 // source type is the same class as, or a derived class of, the 1448 // class of the destination, constructors are considered. The 1449 // applicable constructors are enumerated (13.3.1.3), and the 1450 // best one is chosen through overload resolution (13.3). The 1451 // constructor so selected is called to initialize the object, 1452 // with the initializer expression(s) as its argument(s). If no 1453 // constructor applies, or the overload resolution is ambiguous, 1454 // the initialization is ill-formed. 1455 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1456 OverloadCandidateSet CandidateSet; 1457 1458 // Add constructors to the overload set. 1459 OverloadedFunctionDecl *Constructors 1460 = const_cast<OverloadedFunctionDecl *>(ClassDecl->getConstructors()); 1461 for (OverloadedFunctionDecl::function_iterator Con 1462 = Constructors->function_begin(); 1463 Con != Constructors->function_end(); ++Con) { 1464 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 1465 if ((Kind == IK_Direct) || 1466 (Kind == IK_Copy && Constructor->isConvertingConstructor()) || 1467 (Kind == IK_Default && Constructor->isDefaultConstructor())) 1468 AddOverloadCandidate(Constructor, Args, NumArgs, CandidateSet); 1469 } 1470 1471 OverloadCandidateSet::iterator Best; 1472 switch (BestViableFunction(CandidateSet, Best)) { 1473 case OR_Success: 1474 // We found a constructor. Return it. 1475 return cast<CXXConstructorDecl>(Best->Function); 1476 1477 case OR_No_Viable_Function: 1478 if (CandidateSet.empty()) 1479 Diag(Loc, diag::err_ovl_no_viable_function_in_init, 1480 InitEntity, Range); 1481 else { 1482 Diag(Loc, diag::err_ovl_no_viable_function_in_init_with_cands, 1483 InitEntity, Range); 1484 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1485 } 1486 return 0; 1487 1488 case OR_Ambiguous: 1489 Diag(Loc, diag::err_ovl_ambiguous_init, 1490 InitEntity, Range); 1491 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1492 return 0; 1493 } 1494 1495 return 0; 1496} 1497 1498/// CompareReferenceRelationship - Compare the two types T1 and T2 to 1499/// determine whether they are reference-related, 1500/// reference-compatible, reference-compatible with added 1501/// qualification, or incompatible, for use in C++ initialization by 1502/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 1503/// type, and the first type (T1) is the pointee type of the reference 1504/// type being initialized. 1505Sema::ReferenceCompareResult 1506Sema::CompareReferenceRelationship(QualType T1, QualType T2, 1507 bool& DerivedToBase) { 1508 assert(!T1->isReferenceType() && "T1 must be the pointee type of the reference type"); 1509 assert(!T2->isReferenceType() && "T2 cannot be a reference type"); 1510 1511 T1 = Context.getCanonicalType(T1); 1512 T2 = Context.getCanonicalType(T2); 1513 QualType UnqualT1 = T1.getUnqualifiedType(); 1514 QualType UnqualT2 = T2.getUnqualifiedType(); 1515 1516 // C++ [dcl.init.ref]p4: 1517 // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is 1518 // reference-related to “cv2 T2” if T1 is the same type as T2, or 1519 // T1 is a base class of T2. 1520 if (UnqualT1 == UnqualT2) 1521 DerivedToBase = false; 1522 else if (IsDerivedFrom(UnqualT2, UnqualT1)) 1523 DerivedToBase = true; 1524 else 1525 return Ref_Incompatible; 1526 1527 // At this point, we know that T1 and T2 are reference-related (at 1528 // least). 1529 1530 // C++ [dcl.init.ref]p4: 1531 // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is 1532 // reference-related to T2 and cv1 is the same cv-qualification 1533 // as, or greater cv-qualification than, cv2. For purposes of 1534 // overload resolution, cases for which cv1 is greater 1535 // cv-qualification than cv2 are identified as 1536 // reference-compatible with added qualification (see 13.3.3.2). 1537 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 1538 return Ref_Compatible; 1539 else if (T1.isMoreQualifiedThan(T2)) 1540 return Ref_Compatible_With_Added_Qualification; 1541 else 1542 return Ref_Related; 1543} 1544 1545/// CheckReferenceInit - Check the initialization of a reference 1546/// variable with the given initializer (C++ [dcl.init.ref]). Init is 1547/// the initializer (either a simple initializer or an initializer 1548/// list), and DeclType is the type of the declaration. When ICS is 1549/// non-null, this routine will compute the implicit conversion 1550/// sequence according to C++ [over.ics.ref] and will not produce any 1551/// diagnostics; when ICS is null, it will emit diagnostics when any 1552/// errors are found. Either way, a return value of true indicates 1553/// that there was a failure, a return value of false indicates that 1554/// the reference initialization succeeded. 1555/// 1556/// When @p SuppressUserConversions, user-defined conversions are 1557/// suppressed. 1558bool 1559Sema::CheckReferenceInit(Expr *&Init, QualType &DeclType, 1560 ImplicitConversionSequence *ICS, 1561 bool SuppressUserConversions) { 1562 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 1563 1564 QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); 1565 QualType T2 = Init->getType(); 1566 1567 // If the initializer is the address of an overloaded function, try 1568 // to resolve the overloaded function. If all goes well, T2 is the 1569 // type of the resulting function. 1570 if (T2->isOverloadType()) { 1571 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Init, DeclType, 1572 ICS != 0); 1573 if (Fn) { 1574 // Since we're performing this reference-initialization for 1575 // real, update the initializer with the resulting function. 1576 if (!ICS) 1577 FixOverloadedFunctionReference(Init, Fn); 1578 1579 T2 = Fn->getType(); 1580 } 1581 } 1582 1583 // Compute some basic properties of the types and the initializer. 1584 bool DerivedToBase = false; 1585 Expr::isLvalueResult InitLvalue = Init->isLvalue(Context); 1586 ReferenceCompareResult RefRelationship 1587 = CompareReferenceRelationship(T1, T2, DerivedToBase); 1588 1589 // Most paths end in a failed conversion. 1590 if (ICS) 1591 ICS->ConversionKind = ImplicitConversionSequence::BadConversion; 1592 1593 // C++ [dcl.init.ref]p5: 1594 // A reference to type “cv1 T1” is initialized by an expression 1595 // of type “cv2 T2” as follows: 1596 1597 // -- If the initializer expression 1598 1599 bool BindsDirectly = false; 1600 // -- is an lvalue (but is not a bit-field), and “cv1 T1” is 1601 // reference-compatible with “cv2 T2,” or 1602 // 1603 // Note that the bit-field check is skipped if we are just computing 1604 // the implicit conversion sequence (C++ [over.best.ics]p2). 1605 if (InitLvalue == Expr::LV_Valid && (ICS || !Init->isBitField()) && 1606 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1607 BindsDirectly = true; 1608 1609 if (ICS) { 1610 // C++ [over.ics.ref]p1: 1611 // When a parameter of reference type binds directly (8.5.3) 1612 // to an argument expression, the implicit conversion sequence 1613 // is the identity conversion, unless the argument expression 1614 // has a type that is a derived class of the parameter type, 1615 // in which case the implicit conversion sequence is a 1616 // derived-to-base Conversion (13.3.3.1). 1617 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1618 ICS->Standard.First = ICK_Identity; 1619 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1620 ICS->Standard.Third = ICK_Identity; 1621 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1622 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1623 ICS->Standard.ReferenceBinding = true; 1624 ICS->Standard.DirectBinding = true; 1625 1626 // Nothing more to do: the inaccessibility/ambiguity check for 1627 // derived-to-base conversions is suppressed when we're 1628 // computing the implicit conversion sequence (C++ 1629 // [over.best.ics]p2). 1630 return false; 1631 } else { 1632 // Perform the conversion. 1633 // FIXME: Binding to a subobject of the lvalue is going to require 1634 // more AST annotation than this. 1635 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1636 } 1637 } 1638 1639 // -- has a class type (i.e., T2 is a class type) and can be 1640 // implicitly converted to an lvalue of type “cv3 T3,” 1641 // where “cv1 T1” is reference-compatible with “cv3 T3” 1642 // 92) (this conversion is selected by enumerating the 1643 // applicable conversion functions (13.3.1.6) and choosing 1644 // the best one through overload resolution (13.3)), 1645 if (!SuppressUserConversions && T2->isRecordType()) { 1646 // FIXME: Look for conversions in base classes! 1647 CXXRecordDecl *T2RecordDecl 1648 = dyn_cast<CXXRecordDecl>(T2->getAsRecordType()->getDecl()); 1649 1650 OverloadCandidateSet CandidateSet; 1651 OverloadedFunctionDecl *Conversions 1652 = T2RecordDecl->getConversionFunctions(); 1653 for (OverloadedFunctionDecl::function_iterator Func 1654 = Conversions->function_begin(); 1655 Func != Conversions->function_end(); ++Func) { 1656 CXXConversionDecl *Conv = cast<CXXConversionDecl>(*Func); 1657 1658 // If the conversion function doesn't return a reference type, 1659 // it can't be considered for this conversion. 1660 // FIXME: This will change when we support rvalue references. 1661 if (Conv->getConversionType()->isReferenceType()) 1662 AddConversionCandidate(Conv, Init, DeclType, CandidateSet); 1663 } 1664 1665 OverloadCandidateSet::iterator Best; 1666 switch (BestViableFunction(CandidateSet, Best)) { 1667 case OR_Success: 1668 // This is a direct binding. 1669 BindsDirectly = true; 1670 1671 if (ICS) { 1672 // C++ [over.ics.ref]p1: 1673 // 1674 // [...] If the parameter binds directly to the result of 1675 // applying a conversion function to the argument 1676 // expression, the implicit conversion sequence is a 1677 // user-defined conversion sequence (13.3.3.1.2), with the 1678 // second standard conversion sequence either an identity 1679 // conversion or, if the conversion function returns an 1680 // entity of a type that is a derived class of the parameter 1681 // type, a derived-to-base Conversion. 1682 ICS->ConversionKind = ImplicitConversionSequence::UserDefinedConversion; 1683 ICS->UserDefined.Before = Best->Conversions[0].Standard; 1684 ICS->UserDefined.After = Best->FinalConversion; 1685 ICS->UserDefined.ConversionFunction = Best->Function; 1686 assert(ICS->UserDefined.After.ReferenceBinding && 1687 ICS->UserDefined.After.DirectBinding && 1688 "Expected a direct reference binding!"); 1689 return false; 1690 } else { 1691 // Perform the conversion. 1692 // FIXME: Binding to a subobject of the lvalue is going to require 1693 // more AST annotation than this. 1694 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1695 } 1696 break; 1697 1698 case OR_Ambiguous: 1699 assert(false && "Ambiguous reference binding conversions not implemented."); 1700 return true; 1701 1702 case OR_No_Viable_Function: 1703 // There was no suitable conversion; continue with other checks. 1704 break; 1705 } 1706 } 1707 1708 if (BindsDirectly) { 1709 // C++ [dcl.init.ref]p4: 1710 // [...] In all cases where the reference-related or 1711 // reference-compatible relationship of two types is used to 1712 // establish the validity of a reference binding, and T1 is a 1713 // base class of T2, a program that necessitates such a binding 1714 // is ill-formed if T1 is an inaccessible (clause 11) or 1715 // ambiguous (10.2) base class of T2. 1716 // 1717 // Note that we only check this condition when we're allowed to 1718 // complain about errors, because we should not be checking for 1719 // ambiguity (or inaccessibility) unless the reference binding 1720 // actually happens. 1721 if (DerivedToBase) 1722 return CheckDerivedToBaseConversion(T2, T1, 1723 Init->getSourceRange().getBegin(), 1724 Init->getSourceRange()); 1725 else 1726 return false; 1727 } 1728 1729 // -- Otherwise, the reference shall be to a non-volatile const 1730 // type (i.e., cv1 shall be const). 1731 if (T1.getCVRQualifiers() != QualType::Const) { 1732 if (!ICS) 1733 Diag(Init->getSourceRange().getBegin(), 1734 diag::err_not_reference_to_const_init, 1735 T1.getAsString(), 1736 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1737 T2.getAsString(), Init->getSourceRange()); 1738 return true; 1739 } 1740 1741 // -- If the initializer expression is an rvalue, with T2 a 1742 // class type, and “cv1 T1” is reference-compatible with 1743 // “cv2 T2,” the reference is bound in one of the 1744 // following ways (the choice is implementation-defined): 1745 // 1746 // -- The reference is bound to the object represented by 1747 // the rvalue (see 3.10) or to a sub-object within that 1748 // object. 1749 // 1750 // -- A temporary of type “cv1 T2” [sic] is created, and 1751 // a constructor is called to copy the entire rvalue 1752 // object into the temporary. The reference is bound to 1753 // the temporary or to a sub-object within the 1754 // temporary. 1755 // 1756 // 1757 // The constructor that would be used to make the copy 1758 // shall be callable whether or not the copy is actually 1759 // done. 1760 // 1761 // Note that C++0x [dcl.ref.init]p5 takes away this implementation 1762 // freedom, so we will always take the first option and never build 1763 // a temporary in this case. FIXME: We will, however, have to check 1764 // for the presence of a copy constructor in C++98/03 mode. 1765 if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && 1766 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1767 if (ICS) { 1768 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1769 ICS->Standard.First = ICK_Identity; 1770 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1771 ICS->Standard.Third = ICK_Identity; 1772 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1773 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1774 ICS->Standard.ReferenceBinding = true; 1775 ICS->Standard.DirectBinding = false; 1776 } else { 1777 // FIXME: Binding to a subobject of the rvalue is going to require 1778 // more AST annotation than this. 1779 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1780 } 1781 return false; 1782 } 1783 1784 // -- Otherwise, a temporary of type “cv1 T1” is created and 1785 // initialized from the initializer expression using the 1786 // rules for a non-reference copy initialization (8.5). The 1787 // reference is then bound to the temporary. If T1 is 1788 // reference-related to T2, cv1 must be the same 1789 // cv-qualification as, or greater cv-qualification than, 1790 // cv2; otherwise, the program is ill-formed. 1791 if (RefRelationship == Ref_Related) { 1792 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 1793 // we would be reference-compatible or reference-compatible with 1794 // added qualification. But that wasn't the case, so the reference 1795 // initialization fails. 1796 if (!ICS) 1797 Diag(Init->getSourceRange().getBegin(), 1798 diag::err_reference_init_drops_quals, 1799 T1.getAsString(), 1800 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1801 T2.getAsString(), Init->getSourceRange()); 1802 return true; 1803 } 1804 1805 // Actually try to convert the initializer to T1. 1806 if (ICS) { 1807 /// C++ [over.ics.ref]p2: 1808 /// 1809 /// When a parameter of reference type is not bound directly to 1810 /// an argument expression, the conversion sequence is the one 1811 /// required to convert the argument expression to the 1812 /// underlying type of the reference according to 1813 /// 13.3.3.1. Conceptually, this conversion sequence corresponds 1814 /// to copy-initializing a temporary of the underlying type with 1815 /// the argument expression. Any difference in top-level 1816 /// cv-qualification is subsumed by the initialization itself 1817 /// and does not constitute a conversion. 1818 *ICS = TryImplicitConversion(Init, T1, SuppressUserConversions); 1819 return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; 1820 } else { 1821 return PerformImplicitConversion(Init, T1); 1822 } 1823} 1824 1825/// CheckOverloadedOperatorDeclaration - Check whether the declaration 1826/// of this overloaded operator is well-formed. If so, returns false; 1827/// otherwise, emits appropriate diagnostics and returns true. 1828bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) { 1829 assert(FnDecl && FnDecl->isOverloadedOperator() && 1830 "Expected an overloaded operator declaration"); 1831 1832 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator(); 1833 1834 // C++ [over.oper]p5: 1835 // The allocation and deallocation functions, operator new, 1836 // operator new[], operator delete and operator delete[], are 1837 // described completely in 3.7.3. The attributes and restrictions 1838 // found in the rest of this subclause do not apply to them unless 1839 // explicitly stated in 3.7.3. 1840 // FIXME: Write a separate routine for checking this. For now, just 1841 // allow it. 1842 if (Op == OO_New || Op == OO_Array_New || 1843 Op == OO_Delete || Op == OO_Array_Delete) 1844 return false; 1845 1846 // C++ [over.oper]p6: 1847 // An operator function shall either be a non-static member 1848 // function or be a non-member function and have at least one 1849 // parameter whose type is a class, a reference to a class, an 1850 // enumeration, or a reference to an enumeration. 1851 if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl)) { 1852 if (MethodDecl->isStatic()) 1853 return Diag(FnDecl->getLocation(), 1854 diag::err_operator_overload_static, 1855 FnDecl->getName()); 1856 } else { 1857 bool ClassOrEnumParam = false; 1858 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(), 1859 ParamEnd = FnDecl->param_end(); 1860 Param != ParamEnd; ++Param) { 1861 QualType ParamType = (*Param)->getType().getNonReferenceType(); 1862 if (ParamType->isRecordType() || ParamType->isEnumeralType()) { 1863 ClassOrEnumParam = true; 1864 break; 1865 } 1866 } 1867 1868 if (!ClassOrEnumParam) 1869 return Diag(FnDecl->getLocation(), 1870 diag::err_operator_overload_needs_class_or_enum, 1871 FnDecl->getName()); 1872 } 1873 1874 // C++ [over.oper]p8: 1875 // An operator function cannot have default arguments (8.3.6), 1876 // except where explicitly stated below. 1877 // 1878 // Only the function-call operator allows default arguments 1879 // (C++ [over.call]p1). 1880 if (Op != OO_Call) { 1881 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 1882 Param != FnDecl->param_end(); ++Param) { 1883 if (Expr *DefArg = (*Param)->getDefaultArg()) 1884 return Diag((*Param)->getLocation(), 1885 diag::err_operator_overload_default_arg, 1886 FnDecl->getName(), DefArg->getSourceRange()); 1887 } 1888 } 1889 1890 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = { 1891 { false, false, false } 1892#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \ 1893 , { Unary, Binary, MemberOnly } 1894#include "clang/Basic/OperatorKinds.def" 1895 }; 1896 1897 bool CanBeUnaryOperator = OperatorUses[Op][0]; 1898 bool CanBeBinaryOperator = OperatorUses[Op][1]; 1899 bool MustBeMemberOperator = OperatorUses[Op][2]; 1900 1901 // C++ [over.oper]p8: 1902 // [...] Operator functions cannot have more or fewer parameters 1903 // than the number required for the corresponding operator, as 1904 // described in the rest of this subclause. 1905 unsigned NumParams = FnDecl->getNumParams() 1906 + (isa<CXXMethodDecl>(FnDecl)? 1 : 0); 1907 if (Op != OO_Call && 1908 ((NumParams == 1 && !CanBeUnaryOperator) || 1909 (NumParams == 2 && !CanBeBinaryOperator) || 1910 (NumParams < 1) || (NumParams > 2))) { 1911 // We have the wrong number of parameters. 1912 std::string NumParamsStr = llvm::utostr(NumParams); 1913 1914 diag::kind DK; 1915 1916 if (CanBeUnaryOperator && CanBeBinaryOperator) { 1917 if (NumParams == 1) 1918 DK = diag::err_operator_overload_must_be_unary_or_binary; 1919 else 1920 DK = diag::err_operator_overload_must_be_unary_or_binary; 1921 } else if (CanBeUnaryOperator) { 1922 if (NumParams == 1) 1923 DK = diag::err_operator_overload_must_be_unary; 1924 else 1925 DK = diag::err_operator_overload_must_be_unary_plural; 1926 } else if (CanBeBinaryOperator) { 1927 if (NumParams == 1) 1928 DK = diag::err_operator_overload_must_be_binary; 1929 else 1930 DK = diag::err_operator_overload_must_be_binary_plural; 1931 } else { 1932 assert(false && "All non-call overloaded operators are unary or binary!"); 1933 } 1934 1935 return Diag(FnDecl->getLocation(), DK, 1936 FnDecl->getName(), NumParamsStr); 1937 } 1938 1939 // Overloaded operators other than operator() cannot be variadic. 1940 if (Op != OO_Call && 1941 FnDecl->getType()->getAsFunctionTypeProto()->isVariadic()) { 1942 return Diag(FnDecl->getLocation(), 1943 diag::err_operator_overload_variadic, 1944 FnDecl->getName()); 1945 } 1946 1947 // Some operators must be non-static member functions. 1948 if (MustBeMemberOperator && !isa<CXXMethodDecl>(FnDecl)) { 1949 return Diag(FnDecl->getLocation(), 1950 diag::err_operator_overload_must_be_member, 1951 FnDecl->getName()); 1952 } 1953 1954 // C++ [over.inc]p1: 1955 // The user-defined function called operator++ implements the 1956 // prefix and postfix ++ operator. If this function is a member 1957 // function with no parameters, or a non-member function with one 1958 // parameter of class or enumeration type, it defines the prefix 1959 // increment operator ++ for objects of that type. If the function 1960 // is a member function with one parameter (which shall be of type 1961 // int) or a non-member function with two parameters (the second 1962 // of which shall be of type int), it defines the postfix 1963 // increment operator ++ for objects of that type. 1964 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) { 1965 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1); 1966 bool ParamIsInt = false; 1967 if (const BuiltinType *BT = LastParam->getType()->getAsBuiltinType()) 1968 ParamIsInt = BT->getKind() == BuiltinType::Int; 1969 1970 if (!ParamIsInt) { 1971 diag::kind DK; 1972 if (Op == OO_PlusPlus) 1973 DK = diag::err_operator_overload_post_inc_must_be_int; 1974 else 1975 DK = diag::err_operator_overload_post_dec_must_be_int; 1976 return Diag(LastParam->getLocation(), DK, 1977 Context.getCanonicalType(LastParam->getType()).getAsString()); 1978 } 1979 } 1980 1981 return false; 1982} 1983