SemaDeclCXX.cpp revision a11f42f4bca694b9be91350d0a74815f119e3fbf
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 // FIXME: It would be nicer if the keyword was ignored only for this 451 // declarator. Otherwise we could get follow-up errors. 452 D.getMutableDeclSpec().ClearStorageClassSpecs(); 453 } else { 454 QualType T = GetTypeForDeclarator(D, S); 455 diag::kind err = static_cast<diag::kind>(0); 456 if (T->isReferenceType()) 457 err = diag::err_mutable_reference; 458 else if (T.isConstQualified()) 459 err = diag::err_mutable_const; 460 if (err != 0) { 461 if (DS.getStorageClassSpecLoc().isValid()) 462 Diag(DS.getStorageClassSpecLoc(), err); 463 else 464 Diag(DS.getThreadSpecLoc(), err); 465 // FIXME: It would be nicer if the keyword was ignored only for this 466 // declarator. Otherwise we could get follow-up errors. 467 D.getMutableDeclSpec().ClearStorageClassSpecs(); 468 } 469 } 470 break; 471 default: 472 if (DS.getStorageClassSpecLoc().isValid()) 473 Diag(DS.getStorageClassSpecLoc(), 474 diag::err_storageclass_invalid_for_member); 475 else 476 Diag(DS.getThreadSpecLoc(), diag::err_storageclass_invalid_for_member); 477 D.getMutableDeclSpec().ClearStorageClassSpecs(); 478 } 479 480 if (!isFunc && 481 D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_typedef && 482 D.getNumTypeObjects() == 0) { 483 // Check also for this case: 484 // 485 // typedef int f(); 486 // f a; 487 // 488 Decl *TD = static_cast<Decl *>(DS.getTypeRep()); 489 isFunc = Context.getTypeDeclType(cast<TypeDecl>(TD))->isFunctionType(); 490 } 491 492 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified || 493 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) && 494 !isFunc); 495 496 Decl *Member; 497 bool InvalidDecl = false; 498 499 if (isInstField) 500 Member = static_cast<Decl*>(ActOnField(S, Loc, D, BitWidth)); 501 else 502 Member = static_cast<Decl*>(ActOnDeclarator(S, D, LastInGroup)); 503 504 if (!Member) return LastInGroup; 505 506 assert((Name || isInstField) && "No identifier for non-field ?"); 507 508 // set/getAccess is not part of Decl's interface to avoid bloating it with C++ 509 // specific methods. Use a wrapper class that can be used with all C++ class 510 // member decls. 511 CXXClassMemberWrapper(Member).setAccess(AS); 512 513 // C++ [dcl.init.aggr]p1: 514 // An aggregate is an array or a class (clause 9) with [...] no 515 // private or protected non-static data members (clause 11). 516 if (isInstField && (AS == AS_private || AS == AS_protected)) 517 cast<CXXRecordDecl>(CurContext)->setAggregate(false); 518 519 if (DS.isVirtualSpecified()) { 520 if (!isFunc || DS.getStorageClassSpec() == DeclSpec::SCS_static) { 521 Diag(DS.getVirtualSpecLoc(), diag::err_virtual_non_function); 522 InvalidDecl = true; 523 } else { 524 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(CurContext); 525 CurClass->setAggregate(false); 526 CurClass->setPolymorphic(true); 527 } 528 } 529 530 if (BitWidth) { 531 // C++ 9.6p2: Only when declaring an unnamed bit-field may the 532 // constant-expression be a value equal to zero. 533 // FIXME: Check this. 534 535 if (D.isFunctionDeclarator()) { 536 // FIXME: Emit diagnostic about only constructors taking base initializers 537 // or something similar, when constructor support is in place. 538 Diag(Loc, diag::err_not_bitfield_type, 539 Name.getAsString(), BitWidth->getSourceRange()); 540 InvalidDecl = true; 541 542 } else if (isInstField) { 543 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 544 if (!cast<FieldDecl>(Member)->getType()->isIntegralType()) { 545 Diag(Loc, diag::err_not_integral_type_bitfield, 546 Name.getAsString(), BitWidth->getSourceRange()); 547 InvalidDecl = true; 548 } 549 550 } else if (isa<FunctionDecl>(Member)) { 551 // A function typedef ("typedef int f(); f a;"). 552 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 553 Diag(Loc, diag::err_not_integral_type_bitfield, 554 Name.getAsString(), BitWidth->getSourceRange()); 555 InvalidDecl = true; 556 557 } else if (isa<TypedefDecl>(Member)) { 558 // "cannot declare 'A' to be a bit-field type" 559 Diag(Loc, diag::err_not_bitfield_type, Name.getAsString(), 560 BitWidth->getSourceRange()); 561 InvalidDecl = true; 562 563 } else { 564 assert(isa<CXXClassVarDecl>(Member) && 565 "Didn't we cover all member kinds?"); 566 // C++ 9.6p3: A bit-field shall not be a static member. 567 // "static member 'A' cannot be a bit-field" 568 Diag(Loc, diag::err_static_not_bitfield, Name.getAsString(), 569 BitWidth->getSourceRange()); 570 InvalidDecl = true; 571 } 572 } 573 574 if (Init) { 575 // C++ 9.2p4: A member-declarator can contain a constant-initializer only 576 // if it declares a static member of const integral or const enumeration 577 // type. 578 if (CXXClassVarDecl *CVD = dyn_cast<CXXClassVarDecl>(Member)) { 579 // ...static member of... 580 CVD->setInit(Init); 581 // ...const integral or const enumeration type. 582 if (Context.getCanonicalType(CVD->getType()).isConstQualified() && 583 CVD->getType()->isIntegralType()) { 584 // constant-initializer 585 if (CheckForConstantInitializer(Init, CVD->getType())) 586 InvalidDecl = true; 587 588 } else { 589 // not const integral. 590 Diag(Loc, diag::err_member_initialization, 591 Name.getAsString(), Init->getSourceRange()); 592 InvalidDecl = true; 593 } 594 595 } else { 596 // not static member. 597 Diag(Loc, diag::err_member_initialization, 598 Name.getAsString(), Init->getSourceRange()); 599 InvalidDecl = true; 600 } 601 } 602 603 if (InvalidDecl) 604 Member->setInvalidDecl(); 605 606 if (isInstField) { 607 FieldCollector->Add(cast<CXXFieldDecl>(Member)); 608 return LastInGroup; 609 } 610 return Member; 611} 612 613/// ActOnMemInitializer - Handle a C++ member initializer. 614Sema::MemInitResult 615Sema::ActOnMemInitializer(DeclTy *ConstructorD, 616 Scope *S, 617 IdentifierInfo *MemberOrBase, 618 SourceLocation IdLoc, 619 SourceLocation LParenLoc, 620 ExprTy **Args, unsigned NumArgs, 621 SourceLocation *CommaLocs, 622 SourceLocation RParenLoc) { 623 CXXConstructorDecl *Constructor 624 = dyn_cast<CXXConstructorDecl>((Decl*)ConstructorD); 625 if (!Constructor) { 626 // The user wrote a constructor initializer on a function that is 627 // not a C++ constructor. Ignore the error for now, because we may 628 // have more member initializers coming; we'll diagnose it just 629 // once in ActOnMemInitializers. 630 return true; 631 } 632 633 CXXRecordDecl *ClassDecl = Constructor->getParent(); 634 635 // C++ [class.base.init]p2: 636 // Names in a mem-initializer-id are looked up in the scope of the 637 // constructor’s class and, if not found in that scope, are looked 638 // up in the scope containing the constructor’s 639 // definition. [Note: if the constructor’s class contains a member 640 // with the same name as a direct or virtual base class of the 641 // class, a mem-initializer-id naming the member or base class and 642 // composed of a single identifier refers to the class member. A 643 // mem-initializer-id for the hidden base class may be specified 644 // using a qualified name. ] 645 // Look for a member, first. 646 CXXFieldDecl *Member = ClassDecl->getMember(MemberOrBase); 647 648 // FIXME: Handle members of an anonymous union. 649 650 if (Member) { 651 // FIXME: Perform direct initialization of the member. 652 return new CXXBaseOrMemberInitializer(Member, (Expr **)Args, NumArgs); 653 } 654 655 // It didn't name a member, so see if it names a class. 656 TypeTy *BaseTy = isTypeName(*MemberOrBase, S, 0/*SS*/); 657 if (!BaseTy) 658 return Diag(IdLoc, diag::err_mem_init_not_member_or_class, 659 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 660 661 QualType BaseType = Context.getTypeDeclType((TypeDecl *)BaseTy); 662 if (!BaseType->isRecordType()) 663 return Diag(IdLoc, diag::err_base_init_does_not_name_class, 664 BaseType.getAsString(), SourceRange(IdLoc, RParenLoc)); 665 666 // C++ [class.base.init]p2: 667 // [...] Unless the mem-initializer-id names a nonstatic data 668 // member of the constructor’s class or a direct or virtual base 669 // of that class, the mem-initializer is ill-formed. A 670 // mem-initializer-list can initialize a base class using any 671 // name that denotes that base class type. 672 673 // First, check for a direct base class. 674 const CXXBaseSpecifier *DirectBaseSpec = 0; 675 for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin(); 676 Base != ClassDecl->bases_end(); ++Base) { 677 if (Context.getCanonicalType(BaseType).getUnqualifiedType() == 678 Context.getCanonicalType(Base->getType()).getUnqualifiedType()) { 679 // We found a direct base of this type. That's what we're 680 // initializing. 681 DirectBaseSpec = &*Base; 682 break; 683 } 684 } 685 686 // Check for a virtual base class. 687 // FIXME: We might be able to short-circuit this if we know in 688 // advance that there are no virtual bases. 689 const CXXBaseSpecifier *VirtualBaseSpec = 0; 690 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) { 691 // We haven't found a base yet; search the class hierarchy for a 692 // virtual base class. 693 BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 694 /*DetectVirtual=*/false); 695 if (IsDerivedFrom(Context.getTypeDeclType(ClassDecl), BaseType, Paths)) { 696 for (BasePaths::paths_iterator Path = Paths.begin(); 697 Path != Paths.end(); ++Path) { 698 if (Path->back().Base->isVirtual()) { 699 VirtualBaseSpec = Path->back().Base; 700 break; 701 } 702 } 703 } 704 } 705 706 // C++ [base.class.init]p2: 707 // If a mem-initializer-id is ambiguous because it designates both 708 // a direct non-virtual base class and an inherited virtual base 709 // class, the mem-initializer is ill-formed. 710 if (DirectBaseSpec && VirtualBaseSpec) 711 return Diag(IdLoc, diag::err_base_init_direct_and_virtual, 712 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 713 714 return new CXXBaseOrMemberInitializer(BaseType, (Expr **)Args, NumArgs); 715} 716 717 718void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc, 719 DeclTy *TagDecl, 720 SourceLocation LBrac, 721 SourceLocation RBrac) { 722 ActOnFields(S, RLoc, TagDecl, 723 (DeclTy**)FieldCollector->getCurFields(), 724 FieldCollector->getCurNumFields(), LBrac, RBrac, 0); 725} 726 727/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared 728/// special functions, such as the default constructor, copy 729/// constructor, or destructor, to the given C++ class (C++ 730/// [special]p1). This routine can only be executed just before the 731/// definition of the class is complete. 732void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) { 733 QualType ClassType = Context.getTypeDeclType(ClassDecl); 734 ClassType = Context.getCanonicalType(ClassType); 735 736 if (!ClassDecl->hasUserDeclaredConstructor()) { 737 // C++ [class.ctor]p5: 738 // A default constructor for a class X is a constructor of class X 739 // that can be called without an argument. If there is no 740 // user-declared constructor for class X, a default constructor is 741 // implicitly declared. An implicitly-declared default constructor 742 // is an inline public member of its class. 743 DeclarationName Name 744 = Context.DeclarationNames.getCXXConstructorName(ClassType); 745 CXXConstructorDecl *DefaultCon = 746 CXXConstructorDecl::Create(Context, ClassDecl, 747 ClassDecl->getLocation(), Name, 748 Context.getFunctionType(Context.VoidTy, 749 0, 0, false, 0), 750 /*isExplicit=*/false, 751 /*isInline=*/true, 752 /*isImplicitlyDeclared=*/true); 753 DefaultCon->setAccess(AS_public); 754 ClassDecl->addConstructor(Context, DefaultCon); 755 } 756 757 if (!ClassDecl->hasUserDeclaredCopyConstructor()) { 758 // C++ [class.copy]p4: 759 // If the class definition does not explicitly declare a copy 760 // constructor, one is declared implicitly. 761 762 // C++ [class.copy]p5: 763 // The implicitly-declared copy constructor for a class X will 764 // have the form 765 // 766 // X::X(const X&) 767 // 768 // if 769 bool HasConstCopyConstructor = true; 770 771 // -- each direct or virtual base class B of X has a copy 772 // constructor whose first parameter is of type const B& or 773 // const volatile B&, and 774 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 775 HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { 776 const CXXRecordDecl *BaseClassDecl 777 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 778 HasConstCopyConstructor 779 = BaseClassDecl->hasConstCopyConstructor(Context); 780 } 781 782 // -- for all the nonstatic data members of X that are of a 783 // class type M (or array thereof), each such class type 784 // has a copy constructor whose first parameter is of type 785 // const M& or const volatile M&. 786 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(); 787 HasConstCopyConstructor && Field != ClassDecl->field_end(); ++Field) { 788 QualType FieldType = (*Field)->getType(); 789 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 790 FieldType = Array->getElementType(); 791 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 792 const CXXRecordDecl *FieldClassDecl 793 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 794 HasConstCopyConstructor 795 = FieldClassDecl->hasConstCopyConstructor(Context); 796 } 797 } 798 799 // Otherwise, the implicitly declared copy constructor will have 800 // the form 801 // 802 // X::X(X&) 803 QualType ArgType = Context.getTypeDeclType(ClassDecl); 804 if (HasConstCopyConstructor) 805 ArgType = ArgType.withConst(); 806 ArgType = Context.getReferenceType(ArgType); 807 808 // An implicitly-declared copy constructor is an inline public 809 // member of its class. 810 DeclarationName Name 811 = Context.DeclarationNames.getCXXConstructorName(ClassType); 812 CXXConstructorDecl *CopyConstructor 813 = CXXConstructorDecl::Create(Context, ClassDecl, 814 ClassDecl->getLocation(), Name, 815 Context.getFunctionType(Context.VoidTy, 816 &ArgType, 1, 817 false, 0), 818 /*isExplicit=*/false, 819 /*isInline=*/true, 820 /*isImplicitlyDeclared=*/true); 821 CopyConstructor->setAccess(AS_public); 822 823 // Add the parameter to the constructor. 824 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, 825 ClassDecl->getLocation(), 826 /*IdentifierInfo=*/0, 827 ArgType, VarDecl::None, 0, 0); 828 CopyConstructor->setParams(&FromParam, 1); 829 830 ClassDecl->addConstructor(Context, CopyConstructor); 831 } 832 833 if (!ClassDecl->getDestructor()) { 834 // C++ [class.dtor]p2: 835 // If a class has no user-declared destructor, a destructor is 836 // declared implicitly. An implicitly-declared destructor is an 837 // inline public member of its class. 838 DeclarationName Name 839 = Context.DeclarationNames.getCXXDestructorName(ClassType); 840 CXXDestructorDecl *Destructor 841 = CXXDestructorDecl::Create(Context, ClassDecl, 842 ClassDecl->getLocation(), Name, 843 Context.getFunctionType(Context.VoidTy, 844 0, 0, false, 0), 845 /*isInline=*/true, 846 /*isImplicitlyDeclared=*/true); 847 Destructor->setAccess(AS_public); 848 ClassDecl->setDestructor(Destructor); 849 } 850 851 // FIXME: Implicit copy assignment operator 852} 853 854void Sema::ActOnFinishCXXClassDef(DeclTy *D) { 855 CXXRecordDecl *Rec = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 856 FieldCollector->FinishClass(); 857 AddImplicitlyDeclaredMembersToClass(Rec); 858 PopDeclContext(); 859 860 // Everything, including inline method definitions, have been parsed. 861 // Let the consumer know of the new TagDecl definition. 862 Consumer.HandleTagDeclDefinition(Rec); 863} 864 865/// CheckConstructorDeclarator - Called by ActOnDeclarator to check 866/// the well-formednes of the constructor declarator @p D with type @p 867/// R. If there are any errors in the declarator, this routine will 868/// emit diagnostics and return true. Otherwise, it will return 869/// false. Either way, the type @p R will be updated to reflect a 870/// well-formed type for the constructor. 871bool Sema::CheckConstructorDeclarator(Declarator &D, QualType &R, 872 FunctionDecl::StorageClass& SC) { 873 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 874 bool isInvalid = false; 875 876 // C++ [class.ctor]p3: 877 // A constructor shall not be virtual (10.3) or static (9.4). A 878 // constructor can be invoked for a const, volatile or const 879 // volatile object. A constructor shall not be declared const, 880 // volatile, or const volatile (9.3.2). 881 if (isVirtual) { 882 Diag(D.getIdentifierLoc(), 883 diag::err_constructor_cannot_be, 884 "virtual", 885 SourceRange(D.getDeclSpec().getVirtualSpecLoc()), 886 SourceRange(D.getIdentifierLoc())); 887 isInvalid = true; 888 } 889 if (SC == FunctionDecl::Static) { 890 Diag(D.getIdentifierLoc(), 891 diag::err_constructor_cannot_be, 892 "static", 893 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 894 SourceRange(D.getIdentifierLoc())); 895 isInvalid = true; 896 SC = FunctionDecl::None; 897 } 898 if (D.getDeclSpec().hasTypeSpecifier()) { 899 // Constructors don't have return types, but the parser will 900 // happily parse something like: 901 // 902 // class X { 903 // float X(float); 904 // }; 905 // 906 // The return type will be eliminated later. 907 Diag(D.getIdentifierLoc(), 908 diag::err_constructor_return_type, 909 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 910 SourceRange(D.getIdentifierLoc())); 911 } 912 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 913 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 914 if (FTI.TypeQuals & QualType::Const) 915 Diag(D.getIdentifierLoc(), 916 diag::err_invalid_qualified_constructor, 917 "const", 918 SourceRange(D.getIdentifierLoc())); 919 if (FTI.TypeQuals & QualType::Volatile) 920 Diag(D.getIdentifierLoc(), 921 diag::err_invalid_qualified_constructor, 922 "volatile", 923 SourceRange(D.getIdentifierLoc())); 924 if (FTI.TypeQuals & QualType::Restrict) 925 Diag(D.getIdentifierLoc(), 926 diag::err_invalid_qualified_constructor, 927 "restrict", 928 SourceRange(D.getIdentifierLoc())); 929 } 930 931 // Rebuild the function type "R" without any type qualifiers (in 932 // case any of the errors above fired) and with "void" as the 933 // return type, since constructors don't have return types. We 934 // *always* have to do this, because GetTypeForDeclarator will 935 // put in a result type of "int" when none was specified. 936 const FunctionTypeProto *Proto = R->getAsFunctionTypeProto(); 937 R = Context.getFunctionType(Context.VoidTy, Proto->arg_type_begin(), 938 Proto->getNumArgs(), 939 Proto->isVariadic(), 940 0); 941 942 return isInvalid; 943} 944 945/// CheckDestructorDeclarator - Called by ActOnDeclarator to check 946/// the well-formednes of the destructor declarator @p D with type @p 947/// R. If there are any errors in the declarator, this routine will 948/// emit diagnostics and return true. Otherwise, it will return 949/// false. Either way, the type @p R will be updated to reflect a 950/// well-formed type for the destructor. 951bool Sema::CheckDestructorDeclarator(Declarator &D, QualType &R, 952 FunctionDecl::StorageClass& SC) { 953 bool isInvalid = false; 954 955 // C++ [class.dtor]p1: 956 // [...] A typedef-name that names a class is a class-name 957 // (7.1.3); however, a typedef-name that names a class shall not 958 // be used as the identifier in the declarator for a destructor 959 // declaration. 960 TypeDecl *DeclaratorTypeD = (TypeDecl *)D.getDeclaratorIdType(); 961 if (const TypedefDecl *TypedefD = dyn_cast<TypedefDecl>(DeclaratorTypeD)) { 962 Diag(D.getIdentifierLoc(), 963 diag::err_destructor_typedef_name, 964 TypedefD->getName()); 965 isInvalid = true; 966 } 967 968 // C++ [class.dtor]p2: 969 // A destructor is used to destroy objects of its class type. A 970 // destructor takes no parameters, and no return type can be 971 // specified for it (not even void). The address of a destructor 972 // shall not be taken. A destructor shall not be static. A 973 // destructor can be invoked for a const, volatile or const 974 // volatile object. A destructor shall not be declared const, 975 // volatile or const volatile (9.3.2). 976 if (SC == FunctionDecl::Static) { 977 Diag(D.getIdentifierLoc(), 978 diag::err_destructor_cannot_be, 979 "static", 980 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 981 SourceRange(D.getIdentifierLoc())); 982 isInvalid = true; 983 SC = FunctionDecl::None; 984 } 985 if (D.getDeclSpec().hasTypeSpecifier()) { 986 // Destructors don't have return types, but the parser will 987 // happily parse something like: 988 // 989 // class X { 990 // float ~X(); 991 // }; 992 // 993 // The return type will be eliminated later. 994 Diag(D.getIdentifierLoc(), 995 diag::err_destructor_return_type, 996 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 997 SourceRange(D.getIdentifierLoc())); 998 } 999 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 1000 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1001 if (FTI.TypeQuals & QualType::Const) 1002 Diag(D.getIdentifierLoc(), 1003 diag::err_invalid_qualified_destructor, 1004 "const", 1005 SourceRange(D.getIdentifierLoc())); 1006 if (FTI.TypeQuals & QualType::Volatile) 1007 Diag(D.getIdentifierLoc(), 1008 diag::err_invalid_qualified_destructor, 1009 "volatile", 1010 SourceRange(D.getIdentifierLoc())); 1011 if (FTI.TypeQuals & QualType::Restrict) 1012 Diag(D.getIdentifierLoc(), 1013 diag::err_invalid_qualified_destructor, 1014 "restrict", 1015 SourceRange(D.getIdentifierLoc())); 1016 } 1017 1018 // Make sure we don't have any parameters. 1019 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 1020 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params); 1021 1022 // Delete the parameters. 1023 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1024 if (FTI.NumArgs) { 1025 delete [] FTI.ArgInfo; 1026 FTI.NumArgs = 0; 1027 FTI.ArgInfo = 0; 1028 } 1029 } 1030 1031 // Make sure the destructor isn't variadic. 1032 if (R->getAsFunctionTypeProto()->isVariadic()) 1033 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic); 1034 1035 // Rebuild the function type "R" without any type qualifiers or 1036 // parameters (in case any of the errors above fired) and with 1037 // "void" as the return type, since destructors don't have return 1038 // types. We *always* have to do this, because GetTypeForDeclarator 1039 // will put in a result type of "int" when none was specified. 1040 R = Context.getFunctionType(Context.VoidTy, 0, 0, false, 0); 1041 1042 return isInvalid; 1043} 1044 1045/// CheckConversionDeclarator - Called by ActOnDeclarator to check the 1046/// well-formednes of the conversion function declarator @p D with 1047/// type @p R. If there are any errors in the declarator, this routine 1048/// will emit diagnostics and return true. Otherwise, it will return 1049/// false. Either way, the type @p R will be updated to reflect a 1050/// well-formed type for the conversion operator. 1051bool Sema::CheckConversionDeclarator(Declarator &D, QualType &R, 1052 FunctionDecl::StorageClass& SC) { 1053 bool isInvalid = false; 1054 1055 // C++ [class.conv.fct]p1: 1056 // Neither parameter types nor return type can be specified. The 1057 // type of a conversion function (8.3.5) is “function taking no 1058 // parameter returning conversion-type-id.” 1059 if (SC == FunctionDecl::Static) { 1060 Diag(D.getIdentifierLoc(), 1061 diag::err_conv_function_not_member, 1062 "static", 1063 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 1064 SourceRange(D.getIdentifierLoc())); 1065 isInvalid = true; 1066 SC = FunctionDecl::None; 1067 } 1068 if (D.getDeclSpec().hasTypeSpecifier()) { 1069 // Conversion functions don't have return types, but the parser will 1070 // happily parse something like: 1071 // 1072 // class X { 1073 // float operator bool(); 1074 // }; 1075 // 1076 // The return type will be changed later anyway. 1077 Diag(D.getIdentifierLoc(), 1078 diag::err_conv_function_return_type, 1079 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 1080 SourceRange(D.getIdentifierLoc())); 1081 } 1082 1083 // Make sure we don't have any parameters. 1084 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 1085 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params); 1086 1087 // Delete the parameters. 1088 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1089 if (FTI.NumArgs) { 1090 delete [] FTI.ArgInfo; 1091 FTI.NumArgs = 0; 1092 FTI.ArgInfo = 0; 1093 } 1094 } 1095 1096 // Make sure the conversion function isn't variadic. 1097 if (R->getAsFunctionTypeProto()->isVariadic()) 1098 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic); 1099 1100 // C++ [class.conv.fct]p4: 1101 // The conversion-type-id shall not represent a function type nor 1102 // an array type. 1103 QualType ConvType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1104 if (ConvType->isArrayType()) { 1105 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array); 1106 ConvType = Context.getPointerType(ConvType); 1107 } else if (ConvType->isFunctionType()) { 1108 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function); 1109 ConvType = Context.getPointerType(ConvType); 1110 } 1111 1112 // Rebuild the function type "R" without any parameters (in case any 1113 // of the errors above fired) and with the conversion type as the 1114 // return type. 1115 R = Context.getFunctionType(ConvType, 0, 0, false, 1116 R->getAsFunctionTypeProto()->getTypeQuals()); 1117 1118 return isInvalid; 1119} 1120 1121/// ActOnConstructorDeclarator - Called by ActOnDeclarator to complete 1122/// the declaration of the given C++ constructor ConDecl that was 1123/// built from declarator D. This routine is responsible for checking 1124/// that the newly-created constructor declaration is well-formed and 1125/// for recording it in the C++ class. Example: 1126/// 1127/// @code 1128/// class X { 1129/// X(); // X::X() will be the ConDecl. 1130/// }; 1131/// @endcode 1132Sema::DeclTy *Sema::ActOnConstructorDeclarator(CXXConstructorDecl *ConDecl) { 1133 assert(ConDecl && "Expected to receive a constructor declaration"); 1134 1135 // Check default arguments on the constructor 1136 CheckCXXDefaultArguments(ConDecl); 1137 1138 CXXRecordDecl *ClassDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 1139 if (!ClassDecl) { 1140 ConDecl->setInvalidDecl(); 1141 return ConDecl; 1142 } 1143 1144 // Make sure this constructor is an overload of the existing 1145 // constructors. 1146 OverloadedFunctionDecl::function_iterator MatchedDecl; 1147 if (!IsOverload(ConDecl, ClassDecl->getConstructors(), MatchedDecl)) { 1148 Diag(ConDecl->getLocation(), 1149 diag::err_constructor_redeclared, 1150 SourceRange(ConDecl->getLocation())); 1151 Diag((*MatchedDecl)->getLocation(), 1152 diag::err_previous_declaration, 1153 SourceRange((*MatchedDecl)->getLocation())); 1154 ConDecl->setInvalidDecl(); 1155 return ConDecl; 1156 } 1157 1158 1159 // C++ [class.copy]p3: 1160 // A declaration of a constructor for a class X is ill-formed if 1161 // its first parameter is of type (optionally cv-qualified) X and 1162 // either there are no other parameters or else all other 1163 // parameters have default arguments. 1164 if ((ConDecl->getNumParams() == 1) || 1165 (ConDecl->getNumParams() > 1 && 1166 ConDecl->getParamDecl(1)->getDefaultArg() != 0)) { 1167 QualType ParamType = ConDecl->getParamDecl(0)->getType(); 1168 QualType ClassTy = Context.getTagDeclType( 1169 const_cast<CXXRecordDecl*>(ConDecl->getParent())); 1170 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { 1171 Diag(ConDecl->getLocation(), 1172 diag::err_constructor_byvalue_arg, 1173 SourceRange(ConDecl->getParamDecl(0)->getLocation())); 1174 ConDecl->setInvalidDecl(); 1175 return ConDecl; 1176 } 1177 } 1178 1179 // Add this constructor to the set of constructors of the current 1180 // class. 1181 ClassDecl->addConstructor(Context, ConDecl); 1182 return (DeclTy *)ConDecl; 1183} 1184 1185/// ActOnDestructorDeclarator - Called by ActOnDeclarator to complete 1186/// the declaration of the given C++ @p Destructor. This routine is 1187/// responsible for recording the destructor in the C++ class, if 1188/// possible. 1189Sema::DeclTy *Sema::ActOnDestructorDeclarator(CXXDestructorDecl *Destructor) { 1190 assert(Destructor && "Expected to receive a destructor declaration"); 1191 1192 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1193 1194 // Make sure we aren't redeclaring the destructor. 1195 if (CXXDestructorDecl *PrevDestructor = ClassDecl->getDestructor()) { 1196 Diag(Destructor->getLocation(), diag::err_destructor_redeclared); 1197 Diag(PrevDestructor->getLocation(), 1198 PrevDestructor->isThisDeclarationADefinition()? 1199 diag::err_previous_definition 1200 : diag::err_previous_declaration); 1201 Destructor->setInvalidDecl(); 1202 return Destructor; 1203 } 1204 1205 ClassDecl->setDestructor(Destructor); 1206 return (DeclTy *)Destructor; 1207} 1208 1209/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete 1210/// the declaration of the given C++ conversion function. This routine 1211/// is responsible for recording the conversion function in the C++ 1212/// class, if possible. 1213Sema::DeclTy *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) { 1214 assert(Conversion && "Expected to receive a conversion function declaration"); 1215 1216 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1217 1218 // Make sure we aren't redeclaring the conversion function. 1219 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType()); 1220 OverloadedFunctionDecl *Conversions = ClassDecl->getConversionFunctions(); 1221 for (OverloadedFunctionDecl::function_iterator Func 1222 = Conversions->function_begin(); 1223 Func != Conversions->function_end(); ++Func) { 1224 CXXConversionDecl *OtherConv = cast<CXXConversionDecl>(*Func); 1225 if (ConvType == Context.getCanonicalType(OtherConv->getConversionType())) { 1226 Diag(Conversion->getLocation(), diag::err_conv_function_redeclared); 1227 Diag(OtherConv->getLocation(), 1228 OtherConv->isThisDeclarationADefinition()? 1229 diag::err_previous_definition 1230 : diag::err_previous_declaration); 1231 Conversion->setInvalidDecl(); 1232 return (DeclTy *)Conversion; 1233 } 1234 } 1235 1236 // C++ [class.conv.fct]p1: 1237 // [...] A conversion function is never used to convert a 1238 // (possibly cv-qualified) object to the (possibly cv-qualified) 1239 // same object type (or a reference to it), to a (possibly 1240 // cv-qualified) base class of that type (or a reference to it), 1241 // or to (possibly cv-qualified) void. 1242 // FIXME: Suppress this warning if the conversion function ends up 1243 // being a virtual function that overrides a virtual function in a 1244 // base class. 1245 QualType ClassType 1246 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl)); 1247 if (const ReferenceType *ConvTypeRef = ConvType->getAsReferenceType()) 1248 ConvType = ConvTypeRef->getPointeeType(); 1249 if (ConvType->isRecordType()) { 1250 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType(); 1251 if (ConvType == ClassType) 1252 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used, 1253 ClassType.getAsString()); 1254 else if (IsDerivedFrom(ClassType, ConvType)) 1255 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used, 1256 ClassType.getAsString(), 1257 ConvType.getAsString()); 1258 } else if (ConvType->isVoidType()) { 1259 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used, 1260 ClassType.getAsString(), ConvType.getAsString()); 1261 } 1262 1263 ClassDecl->addConversionFunction(Context, Conversion); 1264 1265 return (DeclTy *)Conversion; 1266} 1267 1268//===----------------------------------------------------------------------===// 1269// Namespace Handling 1270//===----------------------------------------------------------------------===// 1271 1272/// ActOnStartNamespaceDef - This is called at the start of a namespace 1273/// definition. 1274Sema::DeclTy *Sema::ActOnStartNamespaceDef(Scope *NamespcScope, 1275 SourceLocation IdentLoc, 1276 IdentifierInfo *II, 1277 SourceLocation LBrace) { 1278 NamespaceDecl *Namespc = 1279 NamespaceDecl::Create(Context, CurContext, IdentLoc, II); 1280 Namespc->setLBracLoc(LBrace); 1281 1282 Scope *DeclRegionScope = NamespcScope->getParent(); 1283 1284 if (II) { 1285 // C++ [namespace.def]p2: 1286 // The identifier in an original-namespace-definition shall not have been 1287 // previously defined in the declarative region in which the 1288 // original-namespace-definition appears. The identifier in an 1289 // original-namespace-definition is the name of the namespace. Subsequently 1290 // in that declarative region, it is treated as an original-namespace-name. 1291 1292 Decl *PrevDecl = 1293 LookupDecl(II, Decl::IDNS_Tag | Decl::IDNS_Ordinary, DeclRegionScope, 0, 1294 /*enableLazyBuiltinCreation=*/false); 1295 1296 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, DeclRegionScope)) { 1297 if (NamespaceDecl *OrigNS = dyn_cast<NamespaceDecl>(PrevDecl)) { 1298 // This is an extended namespace definition. 1299 // Attach this namespace decl to the chain of extended namespace 1300 // definitions. 1301 NamespaceDecl *NextNS = OrigNS; 1302 while (NextNS->getNextNamespace()) 1303 NextNS = NextNS->getNextNamespace(); 1304 1305 NextNS->setNextNamespace(Namespc); 1306 Namespc->setOriginalNamespace(OrigNS); 1307 1308 // We won't add this decl to the current scope. We want the namespace 1309 // name to return the original namespace decl during a name lookup. 1310 } else { 1311 // This is an invalid name redefinition. 1312 Diag(Namespc->getLocation(), diag::err_redefinition_different_kind, 1313 Namespc->getName()); 1314 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1315 Namespc->setInvalidDecl(); 1316 // Continue on to push Namespc as current DeclContext and return it. 1317 } 1318 } else { 1319 // This namespace name is declared for the first time. 1320 PushOnScopeChains(Namespc, DeclRegionScope); 1321 } 1322 } 1323 else { 1324 // FIXME: Handle anonymous namespaces 1325 } 1326 1327 // Although we could have an invalid decl (i.e. the namespace name is a 1328 // redefinition), push it as current DeclContext and try to continue parsing. 1329 PushDeclContext(Namespc->getOriginalNamespace()); 1330 return Namespc; 1331} 1332 1333/// ActOnFinishNamespaceDef - This callback is called after a namespace is 1334/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. 1335void Sema::ActOnFinishNamespaceDef(DeclTy *D, SourceLocation RBrace) { 1336 Decl *Dcl = static_cast<Decl *>(D); 1337 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); 1338 assert(Namespc && "Invalid parameter, expected NamespaceDecl"); 1339 Namespc->setRBracLoc(RBrace); 1340 PopDeclContext(); 1341} 1342 1343 1344/// AddCXXDirectInitializerToDecl - This action is called immediately after 1345/// ActOnDeclarator, when a C++ direct initializer is present. 1346/// e.g: "int x(1);" 1347void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc, 1348 ExprTy **ExprTys, unsigned NumExprs, 1349 SourceLocation *CommaLocs, 1350 SourceLocation RParenLoc) { 1351 assert(NumExprs != 0 && ExprTys && "missing expressions"); 1352 Decl *RealDecl = static_cast<Decl *>(Dcl); 1353 1354 // If there is no declaration, there was an error parsing it. Just ignore 1355 // the initializer. 1356 if (RealDecl == 0) { 1357 for (unsigned i = 0; i != NumExprs; ++i) 1358 delete static_cast<Expr *>(ExprTys[i]); 1359 return; 1360 } 1361 1362 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1363 if (!VDecl) { 1364 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 1365 RealDecl->setInvalidDecl(); 1366 return; 1367 } 1368 1369 // We will treat direct-initialization as a copy-initialization: 1370 // int x(1); -as-> int x = 1; 1371 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); 1372 // 1373 // Clients that want to distinguish between the two forms, can check for 1374 // direct initializer using VarDecl::hasCXXDirectInitializer(). 1375 // A major benefit is that clients that don't particularly care about which 1376 // exactly form was it (like the CodeGen) can handle both cases without 1377 // special case code. 1378 1379 // C++ 8.5p11: 1380 // The form of initialization (using parentheses or '=') is generally 1381 // insignificant, but does matter when the entity being initialized has a 1382 // class type. 1383 QualType DeclInitType = VDecl->getType(); 1384 if (const ArrayType *Array = Context.getAsArrayType(DeclInitType)) 1385 DeclInitType = Array->getElementType(); 1386 1387 if (VDecl->getType()->isRecordType()) { 1388 CXXConstructorDecl *Constructor 1389 = PerformInitializationByConstructor(DeclInitType, 1390 (Expr **)ExprTys, NumExprs, 1391 VDecl->getLocation(), 1392 SourceRange(VDecl->getLocation(), 1393 RParenLoc), 1394 VDecl->getName(), 1395 IK_Direct); 1396 if (!Constructor) { 1397 RealDecl->setInvalidDecl(); 1398 } 1399 1400 // Let clients know that initialization was done with a direct 1401 // initializer. 1402 VDecl->setCXXDirectInitializer(true); 1403 1404 // FIXME: Add ExprTys and Constructor to the RealDecl as part of 1405 // the initializer. 1406 return; 1407 } 1408 1409 if (NumExprs > 1) { 1410 Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg, 1411 SourceRange(VDecl->getLocation(), RParenLoc)); 1412 RealDecl->setInvalidDecl(); 1413 return; 1414 } 1415 1416 // Let clients know that initialization was done with a direct initializer. 1417 VDecl->setCXXDirectInitializer(true); 1418 1419 assert(NumExprs == 1 && "Expected 1 expression"); 1420 // Set the init expression, handles conversions. 1421 AddInitializerToDecl(Dcl, ExprTys[0]); 1422} 1423 1424/// PerformInitializationByConstructor - Perform initialization by 1425/// constructor (C++ [dcl.init]p14), which may occur as part of 1426/// direct-initialization or copy-initialization. We are initializing 1427/// an object of type @p ClassType with the given arguments @p 1428/// Args. @p Loc is the location in the source code where the 1429/// initializer occurs (e.g., a declaration, member initializer, 1430/// functional cast, etc.) while @p Range covers the whole 1431/// initialization. @p InitEntity is the entity being initialized, 1432/// which may by the name of a declaration or a type. @p Kind is the 1433/// kind of initialization we're performing, which affects whether 1434/// explicit constructors will be considered. When successful, returns 1435/// the constructor that will be used to perform the initialization; 1436/// when the initialization fails, emits a diagnostic and returns 1437/// null. 1438CXXConstructorDecl * 1439Sema::PerformInitializationByConstructor(QualType ClassType, 1440 Expr **Args, unsigned NumArgs, 1441 SourceLocation Loc, SourceRange Range, 1442 std::string InitEntity, 1443 InitializationKind Kind) { 1444 const RecordType *ClassRec = ClassType->getAsRecordType(); 1445 assert(ClassRec && "Can only initialize a class type here"); 1446 1447 // C++ [dcl.init]p14: 1448 // 1449 // If the initialization is direct-initialization, or if it is 1450 // copy-initialization where the cv-unqualified version of the 1451 // source type is the same class as, or a derived class of, the 1452 // class of the destination, constructors are considered. The 1453 // applicable constructors are enumerated (13.3.1.3), and the 1454 // best one is chosen through overload resolution (13.3). The 1455 // constructor so selected is called to initialize the object, 1456 // with the initializer expression(s) as its argument(s). If no 1457 // constructor applies, or the overload resolution is ambiguous, 1458 // the initialization is ill-formed. 1459 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1460 OverloadCandidateSet CandidateSet; 1461 1462 // Add constructors to the overload set. 1463 OverloadedFunctionDecl *Constructors 1464 = const_cast<OverloadedFunctionDecl *>(ClassDecl->getConstructors()); 1465 for (OverloadedFunctionDecl::function_iterator Con 1466 = Constructors->function_begin(); 1467 Con != Constructors->function_end(); ++Con) { 1468 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 1469 if ((Kind == IK_Direct) || 1470 (Kind == IK_Copy && Constructor->isConvertingConstructor()) || 1471 (Kind == IK_Default && Constructor->isDefaultConstructor())) 1472 AddOverloadCandidate(Constructor, Args, NumArgs, CandidateSet); 1473 } 1474 1475 OverloadCandidateSet::iterator Best; 1476 switch (BestViableFunction(CandidateSet, Best)) { 1477 case OR_Success: 1478 // We found a constructor. Return it. 1479 return cast<CXXConstructorDecl>(Best->Function); 1480 1481 case OR_No_Viable_Function: 1482 if (CandidateSet.empty()) 1483 Diag(Loc, diag::err_ovl_no_viable_function_in_init, 1484 InitEntity, Range); 1485 else { 1486 Diag(Loc, diag::err_ovl_no_viable_function_in_init_with_cands, 1487 InitEntity, Range); 1488 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1489 } 1490 return 0; 1491 1492 case OR_Ambiguous: 1493 Diag(Loc, diag::err_ovl_ambiguous_init, 1494 InitEntity, Range); 1495 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1496 return 0; 1497 } 1498 1499 return 0; 1500} 1501 1502/// CompareReferenceRelationship - Compare the two types T1 and T2 to 1503/// determine whether they are reference-related, 1504/// reference-compatible, reference-compatible with added 1505/// qualification, or incompatible, for use in C++ initialization by 1506/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 1507/// type, and the first type (T1) is the pointee type of the reference 1508/// type being initialized. 1509Sema::ReferenceCompareResult 1510Sema::CompareReferenceRelationship(QualType T1, QualType T2, 1511 bool& DerivedToBase) { 1512 assert(!T1->isReferenceType() && "T1 must be the pointee type of the reference type"); 1513 assert(!T2->isReferenceType() && "T2 cannot be a reference type"); 1514 1515 T1 = Context.getCanonicalType(T1); 1516 T2 = Context.getCanonicalType(T2); 1517 QualType UnqualT1 = T1.getUnqualifiedType(); 1518 QualType UnqualT2 = T2.getUnqualifiedType(); 1519 1520 // C++ [dcl.init.ref]p4: 1521 // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is 1522 // reference-related to “cv2 T2” if T1 is the same type as T2, or 1523 // T1 is a base class of T2. 1524 if (UnqualT1 == UnqualT2) 1525 DerivedToBase = false; 1526 else if (IsDerivedFrom(UnqualT2, UnqualT1)) 1527 DerivedToBase = true; 1528 else 1529 return Ref_Incompatible; 1530 1531 // At this point, we know that T1 and T2 are reference-related (at 1532 // least). 1533 1534 // C++ [dcl.init.ref]p4: 1535 // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is 1536 // reference-related to T2 and cv1 is the same cv-qualification 1537 // as, or greater cv-qualification than, cv2. For purposes of 1538 // overload resolution, cases for which cv1 is greater 1539 // cv-qualification than cv2 are identified as 1540 // reference-compatible with added qualification (see 13.3.3.2). 1541 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 1542 return Ref_Compatible; 1543 else if (T1.isMoreQualifiedThan(T2)) 1544 return Ref_Compatible_With_Added_Qualification; 1545 else 1546 return Ref_Related; 1547} 1548 1549/// CheckReferenceInit - Check the initialization of a reference 1550/// variable with the given initializer (C++ [dcl.init.ref]). Init is 1551/// the initializer (either a simple initializer or an initializer 1552/// list), and DeclType is the type of the declaration. When ICS is 1553/// non-null, this routine will compute the implicit conversion 1554/// sequence according to C++ [over.ics.ref] and will not produce any 1555/// diagnostics; when ICS is null, it will emit diagnostics when any 1556/// errors are found. Either way, a return value of true indicates 1557/// that there was a failure, a return value of false indicates that 1558/// the reference initialization succeeded. 1559/// 1560/// When @p SuppressUserConversions, user-defined conversions are 1561/// suppressed. 1562bool 1563Sema::CheckReferenceInit(Expr *&Init, QualType &DeclType, 1564 ImplicitConversionSequence *ICS, 1565 bool SuppressUserConversions) { 1566 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 1567 1568 QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); 1569 QualType T2 = Init->getType(); 1570 1571 // If the initializer is the address of an overloaded function, try 1572 // to resolve the overloaded function. If all goes well, T2 is the 1573 // type of the resulting function. 1574 if (T2->isOverloadType()) { 1575 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Init, DeclType, 1576 ICS != 0); 1577 if (Fn) { 1578 // Since we're performing this reference-initialization for 1579 // real, update the initializer with the resulting function. 1580 if (!ICS) 1581 FixOverloadedFunctionReference(Init, Fn); 1582 1583 T2 = Fn->getType(); 1584 } 1585 } 1586 1587 // Compute some basic properties of the types and the initializer. 1588 bool DerivedToBase = false; 1589 Expr::isLvalueResult InitLvalue = Init->isLvalue(Context); 1590 ReferenceCompareResult RefRelationship 1591 = CompareReferenceRelationship(T1, T2, DerivedToBase); 1592 1593 // Most paths end in a failed conversion. 1594 if (ICS) 1595 ICS->ConversionKind = ImplicitConversionSequence::BadConversion; 1596 1597 // C++ [dcl.init.ref]p5: 1598 // A reference to type “cv1 T1” is initialized by an expression 1599 // of type “cv2 T2” as follows: 1600 1601 // -- If the initializer expression 1602 1603 bool BindsDirectly = false; 1604 // -- is an lvalue (but is not a bit-field), and “cv1 T1” is 1605 // reference-compatible with “cv2 T2,” or 1606 // 1607 // Note that the bit-field check is skipped if we are just computing 1608 // the implicit conversion sequence (C++ [over.best.ics]p2). 1609 if (InitLvalue == Expr::LV_Valid && (ICS || !Init->isBitField()) && 1610 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1611 BindsDirectly = true; 1612 1613 if (ICS) { 1614 // C++ [over.ics.ref]p1: 1615 // When a parameter of reference type binds directly (8.5.3) 1616 // to an argument expression, the implicit conversion sequence 1617 // is the identity conversion, unless the argument expression 1618 // has a type that is a derived class of the parameter type, 1619 // in which case the implicit conversion sequence is a 1620 // derived-to-base Conversion (13.3.3.1). 1621 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1622 ICS->Standard.First = ICK_Identity; 1623 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1624 ICS->Standard.Third = ICK_Identity; 1625 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1626 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1627 ICS->Standard.ReferenceBinding = true; 1628 ICS->Standard.DirectBinding = true; 1629 1630 // Nothing more to do: the inaccessibility/ambiguity check for 1631 // derived-to-base conversions is suppressed when we're 1632 // computing the implicit conversion sequence (C++ 1633 // [over.best.ics]p2). 1634 return false; 1635 } else { 1636 // Perform the conversion. 1637 // FIXME: Binding to a subobject of the lvalue is going to require 1638 // more AST annotation than this. 1639 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1640 } 1641 } 1642 1643 // -- has a class type (i.e., T2 is a class type) and can be 1644 // implicitly converted to an lvalue of type “cv3 T3,” 1645 // where “cv1 T1” is reference-compatible with “cv3 T3” 1646 // 92) (this conversion is selected by enumerating the 1647 // applicable conversion functions (13.3.1.6) and choosing 1648 // the best one through overload resolution (13.3)), 1649 if (!SuppressUserConversions && T2->isRecordType()) { 1650 // FIXME: Look for conversions in base classes! 1651 CXXRecordDecl *T2RecordDecl 1652 = dyn_cast<CXXRecordDecl>(T2->getAsRecordType()->getDecl()); 1653 1654 OverloadCandidateSet CandidateSet; 1655 OverloadedFunctionDecl *Conversions 1656 = T2RecordDecl->getConversionFunctions(); 1657 for (OverloadedFunctionDecl::function_iterator Func 1658 = Conversions->function_begin(); 1659 Func != Conversions->function_end(); ++Func) { 1660 CXXConversionDecl *Conv = cast<CXXConversionDecl>(*Func); 1661 1662 // If the conversion function doesn't return a reference type, 1663 // it can't be considered for this conversion. 1664 // FIXME: This will change when we support rvalue references. 1665 if (Conv->getConversionType()->isReferenceType()) 1666 AddConversionCandidate(Conv, Init, DeclType, CandidateSet); 1667 } 1668 1669 OverloadCandidateSet::iterator Best; 1670 switch (BestViableFunction(CandidateSet, Best)) { 1671 case OR_Success: 1672 // This is a direct binding. 1673 BindsDirectly = true; 1674 1675 if (ICS) { 1676 // C++ [over.ics.ref]p1: 1677 // 1678 // [...] If the parameter binds directly to the result of 1679 // applying a conversion function to the argument 1680 // expression, the implicit conversion sequence is a 1681 // user-defined conversion sequence (13.3.3.1.2), with the 1682 // second standard conversion sequence either an identity 1683 // conversion or, if the conversion function returns an 1684 // entity of a type that is a derived class of the parameter 1685 // type, a derived-to-base Conversion. 1686 ICS->ConversionKind = ImplicitConversionSequence::UserDefinedConversion; 1687 ICS->UserDefined.Before = Best->Conversions[0].Standard; 1688 ICS->UserDefined.After = Best->FinalConversion; 1689 ICS->UserDefined.ConversionFunction = Best->Function; 1690 assert(ICS->UserDefined.After.ReferenceBinding && 1691 ICS->UserDefined.After.DirectBinding && 1692 "Expected a direct reference binding!"); 1693 return false; 1694 } else { 1695 // Perform the conversion. 1696 // FIXME: Binding to a subobject of the lvalue is going to require 1697 // more AST annotation than this. 1698 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1699 } 1700 break; 1701 1702 case OR_Ambiguous: 1703 assert(false && "Ambiguous reference binding conversions not implemented."); 1704 return true; 1705 1706 case OR_No_Viable_Function: 1707 // There was no suitable conversion; continue with other checks. 1708 break; 1709 } 1710 } 1711 1712 if (BindsDirectly) { 1713 // C++ [dcl.init.ref]p4: 1714 // [...] In all cases where the reference-related or 1715 // reference-compatible relationship of two types is used to 1716 // establish the validity of a reference binding, and T1 is a 1717 // base class of T2, a program that necessitates such a binding 1718 // is ill-formed if T1 is an inaccessible (clause 11) or 1719 // ambiguous (10.2) base class of T2. 1720 // 1721 // Note that we only check this condition when we're allowed to 1722 // complain about errors, because we should not be checking for 1723 // ambiguity (or inaccessibility) unless the reference binding 1724 // actually happens. 1725 if (DerivedToBase) 1726 return CheckDerivedToBaseConversion(T2, T1, 1727 Init->getSourceRange().getBegin(), 1728 Init->getSourceRange()); 1729 else 1730 return false; 1731 } 1732 1733 // -- Otherwise, the reference shall be to a non-volatile const 1734 // type (i.e., cv1 shall be const). 1735 if (T1.getCVRQualifiers() != QualType::Const) { 1736 if (!ICS) 1737 Diag(Init->getSourceRange().getBegin(), 1738 diag::err_not_reference_to_const_init, 1739 T1.getAsString(), 1740 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1741 T2.getAsString(), Init->getSourceRange()); 1742 return true; 1743 } 1744 1745 // -- If the initializer expression is an rvalue, with T2 a 1746 // class type, and “cv1 T1” is reference-compatible with 1747 // “cv2 T2,” the reference is bound in one of the 1748 // following ways (the choice is implementation-defined): 1749 // 1750 // -- The reference is bound to the object represented by 1751 // the rvalue (see 3.10) or to a sub-object within that 1752 // object. 1753 // 1754 // -- A temporary of type “cv1 T2” [sic] is created, and 1755 // a constructor is called to copy the entire rvalue 1756 // object into the temporary. The reference is bound to 1757 // the temporary or to a sub-object within the 1758 // temporary. 1759 // 1760 // 1761 // The constructor that would be used to make the copy 1762 // shall be callable whether or not the copy is actually 1763 // done. 1764 // 1765 // Note that C++0x [dcl.ref.init]p5 takes away this implementation 1766 // freedom, so we will always take the first option and never build 1767 // a temporary in this case. FIXME: We will, however, have to check 1768 // for the presence of a copy constructor in C++98/03 mode. 1769 if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && 1770 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1771 if (ICS) { 1772 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1773 ICS->Standard.First = ICK_Identity; 1774 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1775 ICS->Standard.Third = ICK_Identity; 1776 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1777 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1778 ICS->Standard.ReferenceBinding = true; 1779 ICS->Standard.DirectBinding = false; 1780 } else { 1781 // FIXME: Binding to a subobject of the rvalue is going to require 1782 // more AST annotation than this. 1783 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1784 } 1785 return false; 1786 } 1787 1788 // -- Otherwise, a temporary of type “cv1 T1” is created and 1789 // initialized from the initializer expression using the 1790 // rules for a non-reference copy initialization (8.5). The 1791 // reference is then bound to the temporary. If T1 is 1792 // reference-related to T2, cv1 must be the same 1793 // cv-qualification as, or greater cv-qualification than, 1794 // cv2; otherwise, the program is ill-formed. 1795 if (RefRelationship == Ref_Related) { 1796 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 1797 // we would be reference-compatible or reference-compatible with 1798 // added qualification. But that wasn't the case, so the reference 1799 // initialization fails. 1800 if (!ICS) 1801 Diag(Init->getSourceRange().getBegin(), 1802 diag::err_reference_init_drops_quals, 1803 T1.getAsString(), 1804 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1805 T2.getAsString(), Init->getSourceRange()); 1806 return true; 1807 } 1808 1809 // Actually try to convert the initializer to T1. 1810 if (ICS) { 1811 /// C++ [over.ics.ref]p2: 1812 /// 1813 /// When a parameter of reference type is not bound directly to 1814 /// an argument expression, the conversion sequence is the one 1815 /// required to convert the argument expression to the 1816 /// underlying type of the reference according to 1817 /// 13.3.3.1. Conceptually, this conversion sequence corresponds 1818 /// to copy-initializing a temporary of the underlying type with 1819 /// the argument expression. Any difference in top-level 1820 /// cv-qualification is subsumed by the initialization itself 1821 /// and does not constitute a conversion. 1822 *ICS = TryImplicitConversion(Init, T1, SuppressUserConversions); 1823 return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; 1824 } else { 1825 return PerformImplicitConversion(Init, T1); 1826 } 1827} 1828 1829/// CheckOverloadedOperatorDeclaration - Check whether the declaration 1830/// of this overloaded operator is well-formed. If so, returns false; 1831/// otherwise, emits appropriate diagnostics and returns true. 1832bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) { 1833 assert(FnDecl && FnDecl->isOverloadedOperator() && 1834 "Expected an overloaded operator declaration"); 1835 1836 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator(); 1837 1838 // C++ [over.oper]p5: 1839 // The allocation and deallocation functions, operator new, 1840 // operator new[], operator delete and operator delete[], are 1841 // described completely in 3.7.3. The attributes and restrictions 1842 // found in the rest of this subclause do not apply to them unless 1843 // explicitly stated in 3.7.3. 1844 // FIXME: Write a separate routine for checking this. For now, just 1845 // allow it. 1846 if (Op == OO_New || Op == OO_Array_New || 1847 Op == OO_Delete || Op == OO_Array_Delete) 1848 return false; 1849 1850 // C++ [over.oper]p6: 1851 // An operator function shall either be a non-static member 1852 // function or be a non-member function and have at least one 1853 // parameter whose type is a class, a reference to a class, an 1854 // enumeration, or a reference to an enumeration. 1855 if (CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl)) { 1856 if (MethodDecl->isStatic()) 1857 return Diag(FnDecl->getLocation(), 1858 diag::err_operator_overload_static, 1859 FnDecl->getName()); 1860 } else { 1861 bool ClassOrEnumParam = false; 1862 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(), 1863 ParamEnd = FnDecl->param_end(); 1864 Param != ParamEnd; ++Param) { 1865 QualType ParamType = (*Param)->getType().getNonReferenceType(); 1866 if (ParamType->isRecordType() || ParamType->isEnumeralType()) { 1867 ClassOrEnumParam = true; 1868 break; 1869 } 1870 } 1871 1872 if (!ClassOrEnumParam) 1873 return Diag(FnDecl->getLocation(), 1874 diag::err_operator_overload_needs_class_or_enum, 1875 FnDecl->getName()); 1876 } 1877 1878 // C++ [over.oper]p8: 1879 // An operator function cannot have default arguments (8.3.6), 1880 // except where explicitly stated below. 1881 // 1882 // Only the function-call operator allows default arguments 1883 // (C++ [over.call]p1). 1884 if (Op != OO_Call) { 1885 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 1886 Param != FnDecl->param_end(); ++Param) { 1887 if (Expr *DefArg = (*Param)->getDefaultArg()) 1888 return Diag((*Param)->getLocation(), 1889 diag::err_operator_overload_default_arg, 1890 FnDecl->getName(), DefArg->getSourceRange()); 1891 } 1892 } 1893 1894 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = { 1895 { false, false, false } 1896#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \ 1897 , { Unary, Binary, MemberOnly } 1898#include "clang/Basic/OperatorKinds.def" 1899 }; 1900 1901 bool CanBeUnaryOperator = OperatorUses[Op][0]; 1902 bool CanBeBinaryOperator = OperatorUses[Op][1]; 1903 bool MustBeMemberOperator = OperatorUses[Op][2]; 1904 1905 // C++ [over.oper]p8: 1906 // [...] Operator functions cannot have more or fewer parameters 1907 // than the number required for the corresponding operator, as 1908 // described in the rest of this subclause. 1909 unsigned NumParams = FnDecl->getNumParams() 1910 + (isa<CXXMethodDecl>(FnDecl)? 1 : 0); 1911 if (Op != OO_Call && 1912 ((NumParams == 1 && !CanBeUnaryOperator) || 1913 (NumParams == 2 && !CanBeBinaryOperator) || 1914 (NumParams < 1) || (NumParams > 2))) { 1915 // We have the wrong number of parameters. 1916 std::string NumParamsStr = llvm::utostr(NumParams); 1917 1918 diag::kind DK; 1919 1920 if (CanBeUnaryOperator && CanBeBinaryOperator) { 1921 if (NumParams == 1) 1922 DK = diag::err_operator_overload_must_be_unary_or_binary; 1923 else 1924 DK = diag::err_operator_overload_must_be_unary_or_binary; 1925 } else if (CanBeUnaryOperator) { 1926 if (NumParams == 1) 1927 DK = diag::err_operator_overload_must_be_unary; 1928 else 1929 DK = diag::err_operator_overload_must_be_unary_plural; 1930 } else if (CanBeBinaryOperator) { 1931 if (NumParams == 1) 1932 DK = diag::err_operator_overload_must_be_binary; 1933 else 1934 DK = diag::err_operator_overload_must_be_binary_plural; 1935 } else { 1936 assert(false && "All non-call overloaded operators are unary or binary!"); 1937 } 1938 1939 return Diag(FnDecl->getLocation(), DK, 1940 FnDecl->getName(), NumParamsStr); 1941 } 1942 1943 // Overloaded operators other than operator() cannot be variadic. 1944 if (Op != OO_Call && 1945 FnDecl->getType()->getAsFunctionTypeProto()->isVariadic()) { 1946 return Diag(FnDecl->getLocation(), 1947 diag::err_operator_overload_variadic, 1948 FnDecl->getName()); 1949 } 1950 1951 // Some operators must be non-static member functions. 1952 if (MustBeMemberOperator && !isa<CXXMethodDecl>(FnDecl)) { 1953 return Diag(FnDecl->getLocation(), 1954 diag::err_operator_overload_must_be_member, 1955 FnDecl->getName()); 1956 } 1957 1958 // C++ [over.inc]p1: 1959 // The user-defined function called operator++ implements the 1960 // prefix and postfix ++ operator. If this function is a member 1961 // function with no parameters, or a non-member function with one 1962 // parameter of class or enumeration type, it defines the prefix 1963 // increment operator ++ for objects of that type. If the function 1964 // is a member function with one parameter (which shall be of type 1965 // int) or a non-member function with two parameters (the second 1966 // of which shall be of type int), it defines the postfix 1967 // increment operator ++ for objects of that type. 1968 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) { 1969 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1); 1970 bool ParamIsInt = false; 1971 if (const BuiltinType *BT = LastParam->getType()->getAsBuiltinType()) 1972 ParamIsInt = BT->getKind() == BuiltinType::Int; 1973 1974 if (!ParamIsInt) { 1975 diag::kind DK; 1976 if (Op == OO_PlusPlus) 1977 DK = diag::err_operator_overload_post_inc_must_be_int; 1978 else 1979 DK = diag::err_operator_overload_post_dec_must_be_int; 1980 return Diag(LastParam->getLocation(), DK, 1981 Context.getCanonicalType(LastParam->getType()).getAsString()); 1982 } 1983 } 1984 1985 return false; 1986} 1987