SemaDeclCXX.cpp revision 70d2612fd956d4d3aeac8b3abed8ef5e29c4b7a5
1//===------ SemaDeclCXX.cpp - Semantic Analysis for C++ Declarations ------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for C++ declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/TypeOrdering.h" 19#include "clang/AST/StmtVisitor.h" 20#include "clang/Lex/Preprocessor.h" 21#include "clang/Basic/Diagnostic.h" 22#include "clang/Parse/DeclSpec.h" 23#include "llvm/Support/Compiler.h" 24#include <algorithm> // for std::equal 25#include <map> 26 27using namespace clang; 28 29//===----------------------------------------------------------------------===// 30// CheckDefaultArgumentVisitor 31//===----------------------------------------------------------------------===// 32 33namespace { 34 /// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses 35 /// the default argument of a parameter to determine whether it 36 /// contains any ill-formed subexpressions. For example, this will 37 /// diagnose the use of local variables or parameters within the 38 /// default argument expression. 39 class VISIBILITY_HIDDEN CheckDefaultArgumentVisitor 40 : public StmtVisitor<CheckDefaultArgumentVisitor, bool> { 41 Expr *DefaultArg; 42 Sema *S; 43 44 public: 45 CheckDefaultArgumentVisitor(Expr *defarg, Sema *s) 46 : DefaultArg(defarg), S(s) {} 47 48 bool VisitExpr(Expr *Node); 49 bool VisitDeclRefExpr(DeclRefExpr *DRE); 50 bool VisitCXXThisExpr(CXXThisExpr *ThisE); 51 }; 52 53 /// VisitExpr - Visit all of the children of this expression. 54 bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) { 55 bool IsInvalid = false; 56 for (Stmt::child_iterator I = Node->child_begin(), 57 E = Node->child_end(); I != E; ++I) 58 IsInvalid |= Visit(*I); 59 return IsInvalid; 60 } 61 62 /// VisitDeclRefExpr - Visit a reference to a declaration, to 63 /// determine whether this declaration can be used in the default 64 /// argument expression. 65 bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) { 66 NamedDecl *Decl = DRE->getDecl(); 67 if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) { 68 // C++ [dcl.fct.default]p9 69 // Default arguments are evaluated each time the function is 70 // called. The order of evaluation of function arguments is 71 // unspecified. Consequently, parameters of a function shall not 72 // be used in default argument expressions, even if they are not 73 // evaluated. Parameters of a function declared before a default 74 // argument expression are in scope and can hide namespace and 75 // class member names. 76 return S->Diag(DRE->getSourceRange().getBegin(), 77 diag::err_param_default_argument_references_param, 78 Param->getName(), DefaultArg->getSourceRange()); 79 } else if (VarDecl *VDecl = dyn_cast<VarDecl>(Decl)) { 80 // C++ [dcl.fct.default]p7 81 // Local variables shall not be used in default argument 82 // expressions. 83 if (VDecl->isBlockVarDecl()) 84 return S->Diag(DRE->getSourceRange().getBegin(), 85 diag::err_param_default_argument_references_local, 86 VDecl->getName(), DefaultArg->getSourceRange()); 87 } 88 89 return false; 90 } 91 92 /// VisitCXXThisExpr - Visit a C++ "this" expression. 93 bool CheckDefaultArgumentVisitor::VisitCXXThisExpr(CXXThisExpr *ThisE) { 94 // C++ [dcl.fct.default]p8: 95 // The keyword this shall not be used in a default argument of a 96 // member function. 97 return S->Diag(ThisE->getSourceRange().getBegin(), 98 diag::err_param_default_argument_references_this, 99 ThisE->getSourceRange()); 100 } 101} 102 103/// ActOnParamDefaultArgument - Check whether the default argument 104/// provided for a function parameter is well-formed. If so, attach it 105/// to the parameter declaration. 106void 107Sema::ActOnParamDefaultArgument(DeclTy *param, SourceLocation EqualLoc, 108 ExprTy *defarg) { 109 ParmVarDecl *Param = (ParmVarDecl *)param; 110 llvm::OwningPtr<Expr> DefaultArg((Expr *)defarg); 111 QualType ParamType = Param->getType(); 112 113 // Default arguments are only permitted in C++ 114 if (!getLangOptions().CPlusPlus) { 115 Diag(EqualLoc, diag::err_param_default_argument, 116 DefaultArg->getSourceRange()); 117 return; 118 } 119 120 // C++ [dcl.fct.default]p5 121 // A default argument expression is implicitly converted (clause 122 // 4) to the parameter type. The default argument expression has 123 // the same semantic constraints as the initializer expression in 124 // a declaration of a variable of the parameter type, using the 125 // copy-initialization semantics (8.5). 126 Expr *DefaultArgPtr = DefaultArg.get(); 127 bool DefaultInitFailed = PerformCopyInitialization(DefaultArgPtr, ParamType, 128 "in default argument"); 129 if (DefaultArgPtr != DefaultArg.get()) { 130 DefaultArg.take(); 131 DefaultArg.reset(DefaultArgPtr); 132 } 133 if (DefaultInitFailed) { 134 return; 135 } 136 137 // Check that the default argument is well-formed 138 CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg.get(), this); 139 if (DefaultArgChecker.Visit(DefaultArg.get())) 140 return; 141 142 // Okay: add the default argument to the parameter 143 Param->setDefaultArg(DefaultArg.take()); 144} 145 146/// CheckExtraCXXDefaultArguments - Check for any extra default 147/// arguments in the declarator, which is not a function declaration 148/// or definition and therefore is not permitted to have default 149/// arguments. This routine should be invoked for every declarator 150/// that is not a function declaration or definition. 151void Sema::CheckExtraCXXDefaultArguments(Declarator &D) { 152 // C++ [dcl.fct.default]p3 153 // A default argument expression shall be specified only in the 154 // parameter-declaration-clause of a function declaration or in a 155 // template-parameter (14.1). It shall not be specified for a 156 // parameter pack. If it is specified in a 157 // parameter-declaration-clause, it shall not occur within a 158 // declarator or abstract-declarator of a parameter-declaration. 159 for (unsigned i = 0; i < D.getNumTypeObjects(); ++i) { 160 DeclaratorChunk &chunk = D.getTypeObject(i); 161 if (chunk.Kind == DeclaratorChunk::Function) { 162 for (unsigned argIdx = 0; argIdx < chunk.Fun.NumArgs; ++argIdx) { 163 ParmVarDecl *Param = (ParmVarDecl *)chunk.Fun.ArgInfo[argIdx].Param; 164 if (Param->getDefaultArg()) { 165 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc, 166 Param->getDefaultArg()->getSourceRange()); 167 Param->setDefaultArg(0); 168 } 169 } 170 } 171 } 172} 173 174// MergeCXXFunctionDecl - Merge two declarations of the same C++ 175// function, once we already know that they have the same 176// type. Subroutine of MergeFunctionDecl. 177FunctionDecl * 178Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old) { 179 // C++ [dcl.fct.default]p4: 180 // 181 // For non-template functions, default arguments can be added in 182 // later declarations of a function in the same 183 // scope. Declarations in different scopes have completely 184 // distinct sets of default arguments. That is, declarations in 185 // inner scopes do not acquire default arguments from 186 // declarations in outer scopes, and vice versa. In a given 187 // function declaration, all parameters subsequent to a 188 // parameter with a default argument shall have default 189 // arguments supplied in this or previous declarations. A 190 // default argument shall not be redefined by a later 191 // declaration (not even to the same value). 192 for (unsigned p = 0, NumParams = Old->getNumParams(); p < NumParams; ++p) { 193 ParmVarDecl *OldParam = Old->getParamDecl(p); 194 ParmVarDecl *NewParam = New->getParamDecl(p); 195 196 if(OldParam->getDefaultArg() && NewParam->getDefaultArg()) { 197 Diag(NewParam->getLocation(), 198 diag::err_param_default_argument_redefinition, 199 NewParam->getDefaultArg()->getSourceRange()); 200 Diag(OldParam->getLocation(), diag::err_previous_definition); 201 } else if (OldParam->getDefaultArg()) { 202 // Merge the old default argument into the new parameter 203 NewParam->setDefaultArg(OldParam->getDefaultArg()); 204 } 205 } 206 207 return New; 208} 209 210/// CheckCXXDefaultArguments - Verify that the default arguments for a 211/// function declaration are well-formed according to C++ 212/// [dcl.fct.default]. 213void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) { 214 unsigned NumParams = FD->getNumParams(); 215 unsigned p; 216 217 // Find first parameter with a default argument 218 for (p = 0; p < NumParams; ++p) { 219 ParmVarDecl *Param = FD->getParamDecl(p); 220 if (Param->getDefaultArg()) 221 break; 222 } 223 224 // C++ [dcl.fct.default]p4: 225 // In a given function declaration, all parameters 226 // subsequent to a parameter with a default argument shall 227 // have default arguments supplied in this or previous 228 // declarations. A default argument shall not be redefined 229 // by a later declaration (not even to the same value). 230 unsigned LastMissingDefaultArg = 0; 231 for(; p < NumParams; ++p) { 232 ParmVarDecl *Param = FD->getParamDecl(p); 233 if (!Param->getDefaultArg()) { 234 if (Param->getIdentifier()) 235 Diag(Param->getLocation(), 236 diag::err_param_default_argument_missing_name, 237 Param->getIdentifier()->getName()); 238 else 239 Diag(Param->getLocation(), 240 diag::err_param_default_argument_missing); 241 242 LastMissingDefaultArg = p; 243 } 244 } 245 246 if (LastMissingDefaultArg > 0) { 247 // Some default arguments were missing. Clear out all of the 248 // default arguments up to (and including) the last missing 249 // default argument, so that we leave the function parameters 250 // in a semantically valid state. 251 for (p = 0; p <= LastMissingDefaultArg; ++p) { 252 ParmVarDecl *Param = FD->getParamDecl(p); 253 if (Param->getDefaultArg()) { 254 delete Param->getDefaultArg(); 255 Param->setDefaultArg(0); 256 } 257 } 258 } 259} 260 261/// isCurrentClassName - Determine whether the identifier II is the 262/// name of the class type currently being defined. In the case of 263/// nested classes, this will only return true if II is the name of 264/// the innermost class. 265bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *, 266 const CXXScopeSpec *SS) { 267 CXXRecordDecl *CurDecl; 268 if (SS) { 269 DeclContext *DC = static_cast<DeclContext*>(SS->getScopeRep()); 270 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC); 271 } else 272 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 273 274 if (CurDecl) 275 return &II == CurDecl->getIdentifier(); 276 else 277 return false; 278} 279 280/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is 281/// one entry in the base class list of a class specifier, for 282/// example: 283/// class foo : public bar, virtual private baz { 284/// 'public bar' and 'virtual private baz' are each base-specifiers. 285Sema::BaseResult 286Sema::ActOnBaseSpecifier(DeclTy *classdecl, SourceRange SpecifierRange, 287 bool Virtual, AccessSpecifier Access, 288 TypeTy *basetype, SourceLocation BaseLoc) { 289 RecordDecl *Decl = (RecordDecl*)classdecl; 290 QualType BaseType = Context.getTypeDeclType((TypeDecl*)basetype); 291 292 // Base specifiers must be record types. 293 if (!BaseType->isRecordType()) { 294 Diag(BaseLoc, diag::err_base_must_be_class, SpecifierRange); 295 return true; 296 } 297 298 // C++ [class.union]p1: 299 // A union shall not be used as a base class. 300 if (BaseType->isUnionType()) { 301 Diag(BaseLoc, diag::err_union_as_base_class, SpecifierRange); 302 return true; 303 } 304 305 // C++ [class.union]p1: 306 // A union shall not have base classes. 307 if (Decl->isUnion()) { 308 Diag(Decl->getLocation(), diag::err_base_clause_on_union, 309 SpecifierRange); 310 return true; 311 } 312 313 // C++ [class.derived]p2: 314 // The class-name in a base-specifier shall not be an incompletely 315 // defined class. 316 if (BaseType->isIncompleteType()) { 317 Diag(BaseLoc, diag::err_incomplete_base_class, SpecifierRange); 318 return true; 319 } 320 321 // If the base class is polymorphic, the new one is, too. 322 RecordDecl *BaseDecl = BaseType->getAsRecordType()->getDecl(); 323 assert(BaseDecl && "Record type has no declaration"); 324 BaseDecl = BaseDecl->getDefinition(Context); 325 assert(BaseDecl && "Base type is not incomplete, but has no definition"); 326 if (cast<CXXRecordDecl>(BaseDecl)->isPolymorphic()) { 327 cast<CXXRecordDecl>(Decl)->setPolymorphic(true); 328 } 329 330 // Create the base specifier. 331 return new CXXBaseSpecifier(SpecifierRange, Virtual, 332 BaseType->isClassType(), Access, BaseType); 333} 334 335/// ActOnBaseSpecifiers - Attach the given base specifiers to the 336/// class, after checking whether there are any duplicate base 337/// classes. 338void Sema::ActOnBaseSpecifiers(DeclTy *ClassDecl, BaseTy **Bases, 339 unsigned NumBases) { 340 if (NumBases == 0) 341 return; 342 343 // Used to keep track of which base types we have already seen, so 344 // that we can properly diagnose redundant direct base types. Note 345 // that the key is always the unqualified canonical type of the base 346 // class. 347 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes; 348 349 // Copy non-redundant base specifiers into permanent storage. 350 CXXBaseSpecifier **BaseSpecs = (CXXBaseSpecifier **)Bases; 351 unsigned NumGoodBases = 0; 352 for (unsigned idx = 0; idx < NumBases; ++idx) { 353 QualType NewBaseType 354 = Context.getCanonicalType(BaseSpecs[idx]->getType()); 355 NewBaseType = NewBaseType.getUnqualifiedType(); 356 357 if (KnownBaseTypes[NewBaseType]) { 358 // C++ [class.mi]p3: 359 // A class shall not be specified as a direct base class of a 360 // derived class more than once. 361 Diag(BaseSpecs[idx]->getSourceRange().getBegin(), 362 diag::err_duplicate_base_class, 363 KnownBaseTypes[NewBaseType]->getType().getAsString(), 364 BaseSpecs[idx]->getSourceRange()); 365 366 // Delete the duplicate base class specifier; we're going to 367 // overwrite its pointer later. 368 delete BaseSpecs[idx]; 369 } else { 370 // Okay, add this new base class. 371 KnownBaseTypes[NewBaseType] = BaseSpecs[idx]; 372 BaseSpecs[NumGoodBases++] = BaseSpecs[idx]; 373 } 374 } 375 376 // Attach the remaining base class specifiers to the derived class. 377 CXXRecordDecl *Decl = (CXXRecordDecl*)ClassDecl; 378 Decl->setBases(BaseSpecs, NumGoodBases); 379 380 // Delete the remaining (good) base class specifiers, since their 381 // data has been copied into the CXXRecordDecl. 382 for (unsigned idx = 0; idx < NumGoodBases; ++idx) 383 delete BaseSpecs[idx]; 384} 385 386//===----------------------------------------------------------------------===// 387// C++ class member Handling 388//===----------------------------------------------------------------------===// 389 390/// ActOnStartCXXClassDef - This is called at the start of a class/struct/union 391/// definition, when on C++. 392void Sema::ActOnStartCXXClassDef(Scope *S, DeclTy *D, SourceLocation LBrace) { 393 CXXRecordDecl *Dcl = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 394 PushDeclContext(Dcl); 395 FieldCollector->StartClass(); 396 397 if (Dcl->getIdentifier()) { 398 // C++ [class]p2: 399 // [...] The class-name is also inserted into the scope of the 400 // class itself; this is known as the injected-class-name. For 401 // purposes of access checking, the injected-class-name is treated 402 // as if it were a public member name. 403 PushOnScopeChains(Dcl, S); 404 } 405} 406 407/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member 408/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the 409/// bitfield width if there is one and 'InitExpr' specifies the initializer if 410/// any. 'LastInGroup' is non-null for cases where one declspec has multiple 411/// declarators on it. 412/// 413/// NOTE: Because of CXXFieldDecl's inability to be chained like ScopedDecls, if 414/// an instance field is declared, a new CXXFieldDecl is created but the method 415/// does *not* return it; it returns LastInGroup instead. The other C++ members 416/// (which are all ScopedDecls) are returned after appending them to 417/// LastInGroup. 418Sema::DeclTy * 419Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D, 420 ExprTy *BW, ExprTy *InitExpr, 421 DeclTy *LastInGroup) { 422 const DeclSpec &DS = D.getDeclSpec(); 423 IdentifierInfo *II = D.getIdentifier(); 424 Expr *BitWidth = static_cast<Expr*>(BW); 425 Expr *Init = static_cast<Expr*>(InitExpr); 426 SourceLocation Loc = D.getIdentifierLoc(); 427 428 // C++ 9.2p6: A member shall not be declared to have automatic storage 429 // duration (auto, register) or with the extern storage-class-specifier. 430 switch (DS.getStorageClassSpec()) { 431 case DeclSpec::SCS_unspecified: 432 case DeclSpec::SCS_typedef: 433 case DeclSpec::SCS_static: 434 // FALL THROUGH. 435 break; 436 default: 437 if (DS.getStorageClassSpecLoc().isValid()) 438 Diag(DS.getStorageClassSpecLoc(), 439 diag::err_storageclass_invalid_for_member); 440 else 441 Diag(DS.getThreadSpecLoc(), diag::err_storageclass_invalid_for_member); 442 D.getMutableDeclSpec().ClearStorageClassSpecs(); 443 } 444 445 bool isFunc = D.isFunctionDeclarator(); 446 if (!isFunc && 447 D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_typedef && 448 D.getNumTypeObjects() == 0) { 449 // Check also for this case: 450 // 451 // typedef int f(); 452 // f a; 453 // 454 Decl *TD = static_cast<Decl *>(DS.getTypeRep()); 455 isFunc = Context.getTypeDeclType(cast<TypeDecl>(TD))->isFunctionType(); 456 } 457 458 bool isInstField = (DS.getStorageClassSpec() == DeclSpec::SCS_unspecified && 459 !isFunc); 460 461 Decl *Member; 462 bool InvalidDecl = false; 463 464 if (isInstField) 465 Member = static_cast<Decl*>(ActOnField(S, Loc, D, BitWidth)); 466 else 467 Member = static_cast<Decl*>(ActOnDeclarator(S, D, LastInGroup)); 468 469 if (!Member) return LastInGroup; 470 471 assert((II || isInstField) && "No identifier for non-field ?"); 472 473 // set/getAccess is not part of Decl's interface to avoid bloating it with C++ 474 // specific methods. Use a wrapper class that can be used with all C++ class 475 // member decls. 476 CXXClassMemberWrapper(Member).setAccess(AS); 477 478 // C++ [dcl.init.aggr]p1: 479 // An aggregate is an array or a class (clause 9) with [...] no 480 // private or protected non-static data members (clause 11). 481 if (isInstField && (AS == AS_private || AS == AS_protected)) 482 cast<CXXRecordDecl>(CurContext)->setAggregate(false); 483 484 if (DS.isVirtualSpecified()) { 485 if (!isFunc || DS.getStorageClassSpec() == DeclSpec::SCS_static) { 486 Diag(DS.getVirtualSpecLoc(), diag::err_virtual_non_function); 487 InvalidDecl = true; 488 } else { 489 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(CurContext); 490 CurClass->setAggregate(false); 491 CurClass->setPolymorphic(true); 492 } 493 } 494 495 if (BitWidth) { 496 // C++ 9.6p2: Only when declaring an unnamed bit-field may the 497 // constant-expression be a value equal to zero. 498 // FIXME: Check this. 499 500 if (D.isFunctionDeclarator()) { 501 // FIXME: Emit diagnostic about only constructors taking base initializers 502 // or something similar, when constructor support is in place. 503 Diag(Loc, diag::err_not_bitfield_type, 504 II->getName(), BitWidth->getSourceRange()); 505 InvalidDecl = true; 506 507 } else if (isInstField) { 508 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 509 if (!cast<FieldDecl>(Member)->getType()->isIntegralType()) { 510 Diag(Loc, diag::err_not_integral_type_bitfield, 511 II->getName(), BitWidth->getSourceRange()); 512 InvalidDecl = true; 513 } 514 515 } else if (isa<FunctionDecl>(Member)) { 516 // A function typedef ("typedef int f(); f a;"). 517 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 518 Diag(Loc, diag::err_not_integral_type_bitfield, 519 II->getName(), BitWidth->getSourceRange()); 520 InvalidDecl = true; 521 522 } else if (isa<TypedefDecl>(Member)) { 523 // "cannot declare 'A' to be a bit-field type" 524 Diag(Loc, diag::err_not_bitfield_type, II->getName(), 525 BitWidth->getSourceRange()); 526 InvalidDecl = true; 527 528 } else { 529 assert(isa<CXXClassVarDecl>(Member) && 530 "Didn't we cover all member kinds?"); 531 // C++ 9.6p3: A bit-field shall not be a static member. 532 // "static member 'A' cannot be a bit-field" 533 Diag(Loc, diag::err_static_not_bitfield, II->getName(), 534 BitWidth->getSourceRange()); 535 InvalidDecl = true; 536 } 537 } 538 539 if (Init) { 540 // C++ 9.2p4: A member-declarator can contain a constant-initializer only 541 // if it declares a static member of const integral or const enumeration 542 // type. 543 if (CXXClassVarDecl *CVD = dyn_cast<CXXClassVarDecl>(Member)) { 544 // ...static member of... 545 CVD->setInit(Init); 546 // ...const integral or const enumeration type. 547 if (Context.getCanonicalType(CVD->getType()).isConstQualified() && 548 CVD->getType()->isIntegralType()) { 549 // constant-initializer 550 if (CheckForConstantInitializer(Init, CVD->getType())) 551 InvalidDecl = true; 552 553 } else { 554 // not const integral. 555 Diag(Loc, diag::err_member_initialization, 556 II->getName(), Init->getSourceRange()); 557 InvalidDecl = true; 558 } 559 560 } else { 561 // not static member. 562 Diag(Loc, diag::err_member_initialization, 563 II->getName(), Init->getSourceRange()); 564 InvalidDecl = true; 565 } 566 } 567 568 if (InvalidDecl) 569 Member->setInvalidDecl(); 570 571 if (isInstField) { 572 FieldCollector->Add(cast<CXXFieldDecl>(Member)); 573 return LastInGroup; 574 } 575 return Member; 576} 577 578/// ActOnMemInitializer - Handle a C++ member initializer. 579Sema::MemInitResult 580Sema::ActOnMemInitializer(DeclTy *ConstructorD, 581 Scope *S, 582 IdentifierInfo *MemberOrBase, 583 SourceLocation IdLoc, 584 SourceLocation LParenLoc, 585 ExprTy **Args, unsigned NumArgs, 586 SourceLocation *CommaLocs, 587 SourceLocation RParenLoc) { 588 CXXConstructorDecl *Constructor 589 = dyn_cast<CXXConstructorDecl>((Decl*)ConstructorD); 590 if (!Constructor) { 591 // The user wrote a constructor initializer on a function that is 592 // not a C++ constructor. Ignore the error for now, because we may 593 // have more member initializers coming; we'll diagnose it just 594 // once in ActOnMemInitializers. 595 return true; 596 } 597 598 CXXRecordDecl *ClassDecl = Constructor->getParent(); 599 600 // C++ [class.base.init]p2: 601 // Names in a mem-initializer-id are looked up in the scope of the 602 // constructor’s class and, if not found in that scope, are looked 603 // up in the scope containing the constructor’s 604 // definition. [Note: if the constructor’s class contains a member 605 // with the same name as a direct or virtual base class of the 606 // class, a mem-initializer-id naming the member or base class and 607 // composed of a single identifier refers to the class member. A 608 // mem-initializer-id for the hidden base class may be specified 609 // using a qualified name. ] 610 // Look for a member, first. 611 CXXFieldDecl *Member = ClassDecl->getMember(MemberOrBase); 612 613 // FIXME: Handle members of an anonymous union. 614 615 if (Member) { 616 // FIXME: Perform direct initialization of the member. 617 return new CXXBaseOrMemberInitializer(Member, (Expr **)Args, NumArgs); 618 } 619 620 // It didn't name a member, so see if it names a class. 621 TypeTy *BaseTy = isTypeName(*MemberOrBase, S, 0/*SS*/); 622 if (!BaseTy) 623 return Diag(IdLoc, diag::err_mem_init_not_member_or_class, 624 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 625 626 QualType BaseType = Context.getTypeDeclType((TypeDecl *)BaseTy); 627 if (!BaseType->isRecordType()) 628 return Diag(IdLoc, diag::err_base_init_does_not_name_class, 629 BaseType.getAsString(), SourceRange(IdLoc, RParenLoc)); 630 631 // C++ [class.base.init]p2: 632 // [...] Unless the mem-initializer-id names a nonstatic data 633 // member of the constructor’s class or a direct or virtual base 634 // of that class, the mem-initializer is ill-formed. A 635 // mem-initializer-list can initialize a base class using any 636 // name that denotes that base class type. 637 638 // First, check for a direct base class. 639 const CXXBaseSpecifier *DirectBaseSpec = 0; 640 for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin(); 641 Base != ClassDecl->bases_end(); ++Base) { 642 if (Context.getCanonicalType(BaseType).getUnqualifiedType() == 643 Context.getCanonicalType(Base->getType()).getUnqualifiedType()) { 644 // We found a direct base of this type. That's what we're 645 // initializing. 646 DirectBaseSpec = &*Base; 647 break; 648 } 649 } 650 651 // Check for a virtual base class. 652 // FIXME: We might be able to short-circuit this if we know in 653 // advance that there are no virtual bases. 654 const CXXBaseSpecifier *VirtualBaseSpec = 0; 655 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) { 656 // We haven't found a base yet; search the class hierarchy for a 657 // virtual base class. 658 BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 659 /*DetectVirtual=*/false); 660 if (IsDerivedFrom(Context.getTypeDeclType(ClassDecl), BaseType, Paths)) { 661 for (BasePaths::paths_iterator Path = Paths.begin(); 662 Path != Paths.end(); ++Path) { 663 if (Path->back().Base->isVirtual()) { 664 VirtualBaseSpec = Path->back().Base; 665 break; 666 } 667 } 668 } 669 } 670 671 // C++ [base.class.init]p2: 672 // If a mem-initializer-id is ambiguous because it designates both 673 // a direct non-virtual base class and an inherited virtual base 674 // class, the mem-initializer is ill-formed. 675 if (DirectBaseSpec && VirtualBaseSpec) 676 return Diag(IdLoc, diag::err_base_init_direct_and_virtual, 677 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 678 679 return new CXXBaseOrMemberInitializer(BaseType, (Expr **)Args, NumArgs); 680} 681 682 683void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc, 684 DeclTy *TagDecl, 685 SourceLocation LBrac, 686 SourceLocation RBrac) { 687 ActOnFields(S, RLoc, TagDecl, 688 (DeclTy**)FieldCollector->getCurFields(), 689 FieldCollector->getCurNumFields(), LBrac, RBrac, 0); 690} 691 692/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared 693/// special functions, such as the default constructor, copy 694/// constructor, or destructor, to the given C++ class (C++ 695/// [special]p1). This routine can only be executed just before the 696/// definition of the class is complete. 697void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) { 698 if (!ClassDecl->hasUserDeclaredConstructor()) { 699 // C++ [class.ctor]p5: 700 // A default constructor for a class X is a constructor of class X 701 // that can be called without an argument. If there is no 702 // user-declared constructor for class X, a default constructor is 703 // implicitly declared. An implicitly-declared default constructor 704 // is an inline public member of its class. 705 CXXConstructorDecl *DefaultCon = 706 CXXConstructorDecl::Create(Context, ClassDecl, 707 ClassDecl->getLocation(), 708 ClassDecl->getIdentifier(), 709 Context.getFunctionType(Context.VoidTy, 710 0, 0, false, 0), 711 /*isExplicit=*/false, 712 /*isInline=*/true, 713 /*isImplicitlyDeclared=*/true); 714 DefaultCon->setAccess(AS_public); 715 ClassDecl->addConstructor(Context, DefaultCon); 716 } 717 718 if (!ClassDecl->hasUserDeclaredCopyConstructor()) { 719 // C++ [class.copy]p4: 720 // If the class definition does not explicitly declare a copy 721 // constructor, one is declared implicitly. 722 723 // C++ [class.copy]p5: 724 // The implicitly-declared copy constructor for a class X will 725 // have the form 726 // 727 // X::X(const X&) 728 // 729 // if 730 bool HasConstCopyConstructor = true; 731 732 // -- each direct or virtual base class B of X has a copy 733 // constructor whose first parameter is of type const B& or 734 // const volatile B&, and 735 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 736 HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { 737 const CXXRecordDecl *BaseClassDecl 738 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 739 HasConstCopyConstructor 740 = BaseClassDecl->hasConstCopyConstructor(Context); 741 } 742 743 // -- for all the nonstatic data members of X that are of a 744 // class type M (or array thereof), each such class type 745 // has a copy constructor whose first parameter is of type 746 // const M& or const volatile M&. 747 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(); 748 HasConstCopyConstructor && Field != ClassDecl->field_end(); ++Field) { 749 QualType FieldType = (*Field)->getType(); 750 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 751 FieldType = Array->getElementType(); 752 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 753 const CXXRecordDecl *FieldClassDecl 754 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 755 HasConstCopyConstructor 756 = FieldClassDecl->hasConstCopyConstructor(Context); 757 } 758 } 759 760 // Otherwise, the implicitly declared copy constructor will have 761 // the form 762 // 763 // X::X(X&) 764 QualType ArgType = Context.getTypeDeclType(ClassDecl); 765 if (HasConstCopyConstructor) 766 ArgType = ArgType.withConst(); 767 ArgType = Context.getReferenceType(ArgType); 768 769 // An implicitly-declared copy constructor is an inline public 770 // member of its class. 771 CXXConstructorDecl *CopyConstructor 772 = CXXConstructorDecl::Create(Context, ClassDecl, 773 ClassDecl->getLocation(), 774 ClassDecl->getIdentifier(), 775 Context.getFunctionType(Context.VoidTy, 776 &ArgType, 1, 777 false, 0), 778 /*isExplicit=*/false, 779 /*isInline=*/true, 780 /*isImplicitlyDeclared=*/true); 781 CopyConstructor->setAccess(AS_public); 782 783 // Add the parameter to the constructor. 784 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, 785 ClassDecl->getLocation(), 786 /*IdentifierInfo=*/0, 787 ArgType, VarDecl::None, 0, 0); 788 CopyConstructor->setParams(&FromParam, 1); 789 790 ClassDecl->addConstructor(Context, CopyConstructor); 791 } 792 793 if (!ClassDecl->getDestructor()) { 794 // C++ [class.dtor]p2: 795 // If a class has no user-declared destructor, a destructor is 796 // declared implicitly. An implicitly-declared destructor is an 797 // inline public member of its class. 798 std::string DestructorName = "~"; 799 DestructorName += ClassDecl->getName(); 800 CXXDestructorDecl *Destructor 801 = CXXDestructorDecl::Create(Context, ClassDecl, 802 ClassDecl->getLocation(), 803 &PP.getIdentifierTable().get(DestructorName), 804 Context.getFunctionType(Context.VoidTy, 805 0, 0, false, 0), 806 /*isInline=*/true, 807 /*isImplicitlyDeclared=*/true); 808 Destructor->setAccess(AS_public); 809 ClassDecl->setDestructor(Destructor); 810 } 811 812 // FIXME: Implicit copy assignment operator 813} 814 815void Sema::ActOnFinishCXXClassDef(DeclTy *D) { 816 CXXRecordDecl *Rec = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 817 FieldCollector->FinishClass(); 818 AddImplicitlyDeclaredMembersToClass(Rec); 819 PopDeclContext(); 820 821 // Everything, including inline method definitions, have been parsed. 822 // Let the consumer know of the new TagDecl definition. 823 Consumer.HandleTagDeclDefinition(Rec); 824} 825 826/// CheckConstructorDeclarator - Called by ActOnDeclarator to check 827/// the well-formednes of the constructor declarator @p D with type @p 828/// R. If there are any errors in the declarator, this routine will 829/// emit diagnostics and return true. Otherwise, it will return 830/// false. Either way, the type @p R will be updated to reflect a 831/// well-formed type for the constructor. 832bool Sema::CheckConstructorDeclarator(Declarator &D, QualType &R, 833 FunctionDecl::StorageClass& SC) { 834 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 835 bool isInvalid = false; 836 837 // C++ [class.ctor]p3: 838 // A constructor shall not be virtual (10.3) or static (9.4). A 839 // constructor can be invoked for a const, volatile or const 840 // volatile object. A constructor shall not be declared const, 841 // volatile, or const volatile (9.3.2). 842 if (isVirtual) { 843 Diag(D.getIdentifierLoc(), 844 diag::err_constructor_cannot_be, 845 "virtual", 846 SourceRange(D.getDeclSpec().getVirtualSpecLoc()), 847 SourceRange(D.getIdentifierLoc())); 848 isInvalid = true; 849 } 850 if (SC == FunctionDecl::Static) { 851 Diag(D.getIdentifierLoc(), 852 diag::err_constructor_cannot_be, 853 "static", 854 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 855 SourceRange(D.getIdentifierLoc())); 856 isInvalid = true; 857 SC = FunctionDecl::None; 858 } 859 if (D.getDeclSpec().hasTypeSpecifier()) { 860 // Constructors don't have return types, but the parser will 861 // happily parse something like: 862 // 863 // class X { 864 // float X(float); 865 // }; 866 // 867 // The return type will be eliminated later. 868 Diag(D.getIdentifierLoc(), 869 diag::err_constructor_return_type, 870 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 871 SourceRange(D.getIdentifierLoc())); 872 } 873 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 874 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 875 if (FTI.TypeQuals & QualType::Const) 876 Diag(D.getIdentifierLoc(), 877 diag::err_invalid_qualified_constructor, 878 "const", 879 SourceRange(D.getIdentifierLoc())); 880 if (FTI.TypeQuals & QualType::Volatile) 881 Diag(D.getIdentifierLoc(), 882 diag::err_invalid_qualified_constructor, 883 "volatile", 884 SourceRange(D.getIdentifierLoc())); 885 if (FTI.TypeQuals & QualType::Restrict) 886 Diag(D.getIdentifierLoc(), 887 diag::err_invalid_qualified_constructor, 888 "restrict", 889 SourceRange(D.getIdentifierLoc())); 890 } 891 892 // Rebuild the function type "R" without any type qualifiers (in 893 // case any of the errors above fired) and with "void" as the 894 // return type, since constructors don't have return types. We 895 // *always* have to do this, because GetTypeForDeclarator will 896 // put in a result type of "int" when none was specified. 897 const FunctionTypeProto *Proto = R->getAsFunctionTypeProto(); 898 R = Context.getFunctionType(Context.VoidTy, Proto->arg_type_begin(), 899 Proto->getNumArgs(), 900 Proto->isVariadic(), 901 0); 902 903 return isInvalid; 904} 905 906/// CheckDestructorDeclarator - Called by ActOnDeclarator to check 907/// the well-formednes of the destructor declarator @p D with type @p 908/// R. If there are any errors in the declarator, this routine will 909/// emit diagnostics and return true. Otherwise, it will return 910/// false. Either way, the type @p R will be updated to reflect a 911/// well-formed type for the destructor. 912bool Sema::CheckDestructorDeclarator(Declarator &D, QualType &R, 913 FunctionDecl::StorageClass& SC) { 914 bool isInvalid = false; 915 916 // C++ [class.dtor]p1: 917 // [...] A typedef-name that names a class is a class-name 918 // (7.1.3); however, a typedef-name that names a class shall not 919 // be used as the identifier in the declarator for a destructor 920 // declaration. 921 TypeDecl *DeclaratorTypeD = (TypeDecl *)D.getDeclaratorIdType(); 922 if (const TypedefDecl *TypedefD = dyn_cast<TypedefDecl>(DeclaratorTypeD)) { 923 Diag(D.getIdentifierLoc(), 924 diag::err_destructor_typedef_name, 925 TypedefD->getName()); 926 isInvalid = true; 927 } 928 929 // C++ [class.dtor]p2: 930 // A destructor is used to destroy objects of its class type. A 931 // destructor takes no parameters, and no return type can be 932 // specified for it (not even void). The address of a destructor 933 // shall not be taken. A destructor shall not be static. A 934 // destructor can be invoked for a const, volatile or const 935 // volatile object. A destructor shall not be declared const, 936 // volatile or const volatile (9.3.2). 937 if (SC == FunctionDecl::Static) { 938 Diag(D.getIdentifierLoc(), 939 diag::err_destructor_cannot_be, 940 "static", 941 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 942 SourceRange(D.getIdentifierLoc())); 943 isInvalid = true; 944 SC = FunctionDecl::None; 945 } 946 if (D.getDeclSpec().hasTypeSpecifier()) { 947 // Destructors don't have return types, but the parser will 948 // happily parse something like: 949 // 950 // class X { 951 // float ~X(); 952 // }; 953 // 954 // The return type will be eliminated later. 955 Diag(D.getIdentifierLoc(), 956 diag::err_destructor_return_type, 957 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 958 SourceRange(D.getIdentifierLoc())); 959 } 960 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 961 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 962 if (FTI.TypeQuals & QualType::Const) 963 Diag(D.getIdentifierLoc(), 964 diag::err_invalid_qualified_destructor, 965 "const", 966 SourceRange(D.getIdentifierLoc())); 967 if (FTI.TypeQuals & QualType::Volatile) 968 Diag(D.getIdentifierLoc(), 969 diag::err_invalid_qualified_destructor, 970 "volatile", 971 SourceRange(D.getIdentifierLoc())); 972 if (FTI.TypeQuals & QualType::Restrict) 973 Diag(D.getIdentifierLoc(), 974 diag::err_invalid_qualified_destructor, 975 "restrict", 976 SourceRange(D.getIdentifierLoc())); 977 } 978 979 // Make sure we don't have any parameters. 980 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 981 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params); 982 983 // Delete the parameters. 984 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 985 if (FTI.NumArgs) { 986 delete [] FTI.ArgInfo; 987 FTI.NumArgs = 0; 988 FTI.ArgInfo = 0; 989 } 990 } 991 992 // Make sure the destructor isn't variadic. 993 if (R->getAsFunctionTypeProto()->isVariadic()) 994 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic); 995 996 // Rebuild the function type "R" without any type qualifiers or 997 // parameters (in case any of the errors above fired) and with 998 // "void" as the return type, since destructors don't have return 999 // types. We *always* have to do this, because GetTypeForDeclarator 1000 // will put in a result type of "int" when none was specified. 1001 R = Context.getFunctionType(Context.VoidTy, 0, 0, false, 0); 1002 1003 return isInvalid; 1004} 1005 1006/// CheckConversionDeclarator - Called by ActOnDeclarator to check the 1007/// well-formednes of the conversion function declarator @p D with 1008/// type @p R. If there are any errors in the declarator, this routine 1009/// will emit diagnostics and return true. Otherwise, it will return 1010/// false. Either way, the type @p R will be updated to reflect a 1011/// well-formed type for the conversion operator. 1012bool Sema::CheckConversionDeclarator(Declarator &D, QualType &R, 1013 FunctionDecl::StorageClass& SC) { 1014 bool isInvalid = false; 1015 1016 // C++ [class.conv.fct]p1: 1017 // Neither parameter types nor return type can be specified. The 1018 // type of a conversion function (8.3.5) is “function taking no 1019 // parameter returning conversion-type-id.” 1020 if (SC == FunctionDecl::Static) { 1021 Diag(D.getIdentifierLoc(), 1022 diag::err_conv_function_not_member, 1023 "static", 1024 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 1025 SourceRange(D.getIdentifierLoc())); 1026 isInvalid = true; 1027 SC = FunctionDecl::None; 1028 } 1029 if (D.getDeclSpec().hasTypeSpecifier()) { 1030 // Conversion functions don't have return types, but the parser will 1031 // happily parse something like: 1032 // 1033 // class X { 1034 // float operator bool(); 1035 // }; 1036 // 1037 // The return type will be changed later anyway. 1038 Diag(D.getIdentifierLoc(), 1039 diag::err_conv_function_return_type, 1040 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 1041 SourceRange(D.getIdentifierLoc())); 1042 } 1043 1044 // Make sure we don't have any parameters. 1045 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 1046 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params); 1047 1048 // Delete the parameters. 1049 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1050 if (FTI.NumArgs) { 1051 delete [] FTI.ArgInfo; 1052 FTI.NumArgs = 0; 1053 FTI.ArgInfo = 0; 1054 } 1055 } 1056 1057 // Make sure the conversion function isn't variadic. 1058 if (R->getAsFunctionTypeProto()->isVariadic()) 1059 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic); 1060 1061 // C++ [class.conv.fct]p4: 1062 // The conversion-type-id shall not represent a function type nor 1063 // an array type. 1064 QualType ConvType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1065 if (ConvType->isArrayType()) { 1066 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array); 1067 ConvType = Context.getPointerType(ConvType); 1068 } else if (ConvType->isFunctionType()) { 1069 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function); 1070 ConvType = Context.getPointerType(ConvType); 1071 } 1072 1073 // Rebuild the function type "R" without any parameters (in case any 1074 // of the errors above fired) and with the conversion type as the 1075 // return type. 1076 R = Context.getFunctionType(ConvType, 0, 0, false, 1077 R->getAsFunctionTypeProto()->getTypeQuals()); 1078 1079 return isInvalid; 1080} 1081 1082/// ActOnConstructorDeclarator - Called by ActOnDeclarator to complete 1083/// the declaration of the given C++ constructor ConDecl that was 1084/// built from declarator D. This routine is responsible for checking 1085/// that the newly-created constructor declaration is well-formed and 1086/// for recording it in the C++ class. Example: 1087/// 1088/// @code 1089/// class X { 1090/// X(); // X::X() will be the ConDecl. 1091/// }; 1092/// @endcode 1093Sema::DeclTy *Sema::ActOnConstructorDeclarator(CXXConstructorDecl *ConDecl) { 1094 assert(ConDecl && "Expected to receive a constructor declaration"); 1095 1096 // Check default arguments on the constructor 1097 CheckCXXDefaultArguments(ConDecl); 1098 1099 CXXRecordDecl *ClassDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 1100 if (!ClassDecl) { 1101 ConDecl->setInvalidDecl(); 1102 return ConDecl; 1103 } 1104 1105 // Make sure this constructor is an overload of the existing 1106 // constructors. 1107 OverloadedFunctionDecl::function_iterator MatchedDecl; 1108 if (!IsOverload(ConDecl, ClassDecl->getConstructors(), MatchedDecl)) { 1109 Diag(ConDecl->getLocation(), 1110 diag::err_constructor_redeclared, 1111 SourceRange(ConDecl->getLocation())); 1112 Diag((*MatchedDecl)->getLocation(), 1113 diag::err_previous_declaration, 1114 SourceRange((*MatchedDecl)->getLocation())); 1115 ConDecl->setInvalidDecl(); 1116 return ConDecl; 1117 } 1118 1119 1120 // C++ [class.copy]p3: 1121 // A declaration of a constructor for a class X is ill-formed if 1122 // its first parameter is of type (optionally cv-qualified) X and 1123 // either there are no other parameters or else all other 1124 // parameters have default arguments. 1125 if ((ConDecl->getNumParams() == 1) || 1126 (ConDecl->getNumParams() > 1 && 1127 ConDecl->getParamDecl(1)->getDefaultArg() != 0)) { 1128 QualType ParamType = ConDecl->getParamDecl(0)->getType(); 1129 QualType ClassTy = Context.getTagDeclType( 1130 const_cast<CXXRecordDecl*>(ConDecl->getParent())); 1131 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { 1132 Diag(ConDecl->getLocation(), 1133 diag::err_constructor_byvalue_arg, 1134 SourceRange(ConDecl->getParamDecl(0)->getLocation())); 1135 ConDecl->setInvalidDecl(); 1136 return ConDecl; 1137 } 1138 } 1139 1140 // Add this constructor to the set of constructors of the current 1141 // class. 1142 ClassDecl->addConstructor(Context, ConDecl); 1143 return (DeclTy *)ConDecl; 1144} 1145 1146/// ActOnDestructorDeclarator - Called by ActOnDeclarator to complete 1147/// the declaration of the given C++ @p Destructor. This routine is 1148/// responsible for recording the destructor in the C++ class, if 1149/// possible. 1150Sema::DeclTy *Sema::ActOnDestructorDeclarator(CXXDestructorDecl *Destructor) { 1151 assert(Destructor && "Expected to receive a destructor declaration"); 1152 1153 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1154 1155 // Make sure we aren't redeclaring the destructor. 1156 if (CXXDestructorDecl *PrevDestructor = ClassDecl->getDestructor()) { 1157 Diag(Destructor->getLocation(), diag::err_destructor_redeclared); 1158 Diag(PrevDestructor->getLocation(), 1159 PrevDestructor->isThisDeclarationADefinition()? 1160 diag::err_previous_definition 1161 : diag::err_previous_declaration); 1162 Destructor->setInvalidDecl(); 1163 return Destructor; 1164 } 1165 1166 ClassDecl->setDestructor(Destructor); 1167 return (DeclTy *)Destructor; 1168} 1169 1170/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete 1171/// the declaration of the given C++ conversion function. This routine 1172/// is responsible for recording the conversion function in the C++ 1173/// class, if possible. 1174Sema::DeclTy *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) { 1175 assert(Conversion && "Expected to receive a conversion function declaration"); 1176 1177 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1178 1179 // Make sure we aren't redeclaring the conversion function. 1180 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType()); 1181 OverloadedFunctionDecl *Conversions = ClassDecl->getConversionFunctions(); 1182 for (OverloadedFunctionDecl::function_iterator Func 1183 = Conversions->function_begin(); 1184 Func != Conversions->function_end(); ++Func) { 1185 CXXConversionDecl *OtherConv = cast<CXXConversionDecl>(*Func); 1186 if (ConvType == Context.getCanonicalType(OtherConv->getConversionType())) { 1187 Diag(Conversion->getLocation(), diag::err_conv_function_redeclared); 1188 Diag(OtherConv->getLocation(), 1189 OtherConv->isThisDeclarationADefinition()? 1190 diag::err_previous_definition 1191 : diag::err_previous_declaration); 1192 Conversion->setInvalidDecl(); 1193 return (DeclTy *)Conversion; 1194 } 1195 } 1196 1197 // C++ [class.conv.fct]p1: 1198 // [...] A conversion function is never used to convert a 1199 // (possibly cv-qualified) object to the (possibly cv-qualified) 1200 // same object type (or a reference to it), to a (possibly 1201 // cv-qualified) base class of that type (or a reference to it), 1202 // or to (possibly cv-qualified) void. 1203 // FIXME: Suppress this warning if the conversion function ends up 1204 // being a virtual function that overrides a virtual function in a 1205 // base class. 1206 QualType ClassType 1207 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl)); 1208 if (const ReferenceType *ConvTypeRef = ConvType->getAsReferenceType()) 1209 ConvType = ConvTypeRef->getPointeeType(); 1210 if (ConvType->isRecordType()) { 1211 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType(); 1212 if (ConvType == ClassType) 1213 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used, 1214 ClassType.getAsString()); 1215 else if (IsDerivedFrom(ClassType, ConvType)) 1216 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used, 1217 ClassType.getAsString(), 1218 ConvType.getAsString()); 1219 } else if (ConvType->isVoidType()) { 1220 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used, 1221 ClassType.getAsString(), ConvType.getAsString()); 1222 } 1223 1224 ClassDecl->addConversionFunction(Context, Conversion); 1225 1226 return (DeclTy *)Conversion; 1227} 1228 1229//===----------------------------------------------------------------------===// 1230// Namespace Handling 1231//===----------------------------------------------------------------------===// 1232 1233/// ActOnStartNamespaceDef - This is called at the start of a namespace 1234/// definition. 1235Sema::DeclTy *Sema::ActOnStartNamespaceDef(Scope *NamespcScope, 1236 SourceLocation IdentLoc, 1237 IdentifierInfo *II, 1238 SourceLocation LBrace) { 1239 NamespaceDecl *Namespc = 1240 NamespaceDecl::Create(Context, CurContext, IdentLoc, II); 1241 Namespc->setLBracLoc(LBrace); 1242 1243 Scope *DeclRegionScope = NamespcScope->getParent(); 1244 1245 if (II) { 1246 // C++ [namespace.def]p2: 1247 // The identifier in an original-namespace-definition shall not have been 1248 // previously defined in the declarative region in which the 1249 // original-namespace-definition appears. The identifier in an 1250 // original-namespace-definition is the name of the namespace. Subsequently 1251 // in that declarative region, it is treated as an original-namespace-name. 1252 1253 Decl *PrevDecl = 1254 LookupDecl(II, Decl::IDNS_Tag | Decl::IDNS_Ordinary, DeclRegionScope, 0, 1255 /*enableLazyBuiltinCreation=*/false); 1256 1257 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, DeclRegionScope)) { 1258 if (NamespaceDecl *OrigNS = dyn_cast<NamespaceDecl>(PrevDecl)) { 1259 // This is an extended namespace definition. 1260 // Attach this namespace decl to the chain of extended namespace 1261 // definitions. 1262 NamespaceDecl *NextNS = OrigNS; 1263 while (NextNS->getNextNamespace()) 1264 NextNS = NextNS->getNextNamespace(); 1265 1266 NextNS->setNextNamespace(Namespc); 1267 Namespc->setOriginalNamespace(OrigNS); 1268 1269 // We won't add this decl to the current scope. We want the namespace 1270 // name to return the original namespace decl during a name lookup. 1271 } else { 1272 // This is an invalid name redefinition. 1273 Diag(Namespc->getLocation(), diag::err_redefinition_different_kind, 1274 Namespc->getName()); 1275 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1276 Namespc->setInvalidDecl(); 1277 // Continue on to push Namespc as current DeclContext and return it. 1278 } 1279 } else { 1280 // This namespace name is declared for the first time. 1281 PushOnScopeChains(Namespc, DeclRegionScope); 1282 } 1283 } 1284 else { 1285 // FIXME: Handle anonymous namespaces 1286 } 1287 1288 // Although we could have an invalid decl (i.e. the namespace name is a 1289 // redefinition), push it as current DeclContext and try to continue parsing. 1290 PushDeclContext(Namespc->getOriginalNamespace()); 1291 return Namespc; 1292} 1293 1294/// ActOnFinishNamespaceDef - This callback is called after a namespace is 1295/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. 1296void Sema::ActOnFinishNamespaceDef(DeclTy *D, SourceLocation RBrace) { 1297 Decl *Dcl = static_cast<Decl *>(D); 1298 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); 1299 assert(Namespc && "Invalid parameter, expected NamespaceDecl"); 1300 Namespc->setRBracLoc(RBrace); 1301 PopDeclContext(); 1302} 1303 1304 1305/// AddCXXDirectInitializerToDecl - This action is called immediately after 1306/// ActOnDeclarator, when a C++ direct initializer is present. 1307/// e.g: "int x(1);" 1308void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc, 1309 ExprTy **ExprTys, unsigned NumExprs, 1310 SourceLocation *CommaLocs, 1311 SourceLocation RParenLoc) { 1312 assert(NumExprs != 0 && ExprTys && "missing expressions"); 1313 Decl *RealDecl = static_cast<Decl *>(Dcl); 1314 1315 // If there is no declaration, there was an error parsing it. Just ignore 1316 // the initializer. 1317 if (RealDecl == 0) { 1318 for (unsigned i = 0; i != NumExprs; ++i) 1319 delete static_cast<Expr *>(ExprTys[i]); 1320 return; 1321 } 1322 1323 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1324 if (!VDecl) { 1325 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 1326 RealDecl->setInvalidDecl(); 1327 return; 1328 } 1329 1330 // We will treat direct-initialization as a copy-initialization: 1331 // int x(1); -as-> int x = 1; 1332 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); 1333 // 1334 // Clients that want to distinguish between the two forms, can check for 1335 // direct initializer using VarDecl::hasCXXDirectInitializer(). 1336 // A major benefit is that clients that don't particularly care about which 1337 // exactly form was it (like the CodeGen) can handle both cases without 1338 // special case code. 1339 1340 // C++ 8.5p11: 1341 // The form of initialization (using parentheses or '=') is generally 1342 // insignificant, but does matter when the entity being initialized has a 1343 // class type. 1344 QualType DeclInitType = VDecl->getType(); 1345 if (const ArrayType *Array = Context.getAsArrayType(DeclInitType)) 1346 DeclInitType = Array->getElementType(); 1347 1348 if (VDecl->getType()->isRecordType()) { 1349 CXXConstructorDecl *Constructor 1350 = PerformInitializationByConstructor(DeclInitType, 1351 (Expr **)ExprTys, NumExprs, 1352 VDecl->getLocation(), 1353 SourceRange(VDecl->getLocation(), 1354 RParenLoc), 1355 VDecl->getName(), 1356 IK_Direct); 1357 if (!Constructor) { 1358 RealDecl->setInvalidDecl(); 1359 } 1360 1361 // Let clients know that initialization was done with a direct 1362 // initializer. 1363 VDecl->setCXXDirectInitializer(true); 1364 1365 // FIXME: Add ExprTys and Constructor to the RealDecl as part of 1366 // the initializer. 1367 return; 1368 } 1369 1370 if (NumExprs > 1) { 1371 Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg, 1372 SourceRange(VDecl->getLocation(), RParenLoc)); 1373 RealDecl->setInvalidDecl(); 1374 return; 1375 } 1376 1377 // Let clients know that initialization was done with a direct initializer. 1378 VDecl->setCXXDirectInitializer(true); 1379 1380 assert(NumExprs == 1 && "Expected 1 expression"); 1381 // Set the init expression, handles conversions. 1382 AddInitializerToDecl(Dcl, ExprTys[0]); 1383} 1384 1385/// PerformInitializationByConstructor - Perform initialization by 1386/// constructor (C++ [dcl.init]p14), which may occur as part of 1387/// direct-initialization or copy-initialization. We are initializing 1388/// an object of type @p ClassType with the given arguments @p 1389/// Args. @p Loc is the location in the source code where the 1390/// initializer occurs (e.g., a declaration, member initializer, 1391/// functional cast, etc.) while @p Range covers the whole 1392/// initialization. @p InitEntity is the entity being initialized, 1393/// which may by the name of a declaration or a type. @p Kind is the 1394/// kind of initialization we're performing, which affects whether 1395/// explicit constructors will be considered. When successful, returns 1396/// the constructor that will be used to perform the initialization; 1397/// when the initialization fails, emits a diagnostic and returns 1398/// null. 1399CXXConstructorDecl * 1400Sema::PerformInitializationByConstructor(QualType ClassType, 1401 Expr **Args, unsigned NumArgs, 1402 SourceLocation Loc, SourceRange Range, 1403 std::string InitEntity, 1404 InitializationKind Kind) { 1405 const RecordType *ClassRec = ClassType->getAsRecordType(); 1406 assert(ClassRec && "Can only initialize a class type here"); 1407 1408 // C++ [dcl.init]p14: 1409 // 1410 // If the initialization is direct-initialization, or if it is 1411 // copy-initialization where the cv-unqualified version of the 1412 // source type is the same class as, or a derived class of, the 1413 // class of the destination, constructors are considered. The 1414 // applicable constructors are enumerated (13.3.1.3), and the 1415 // best one is chosen through overload resolution (13.3). The 1416 // constructor so selected is called to initialize the object, 1417 // with the initializer expression(s) as its argument(s). If no 1418 // constructor applies, or the overload resolution is ambiguous, 1419 // the initialization is ill-formed. 1420 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1421 OverloadCandidateSet CandidateSet; 1422 1423 // Add constructors to the overload set. 1424 OverloadedFunctionDecl *Constructors 1425 = const_cast<OverloadedFunctionDecl *>(ClassDecl->getConstructors()); 1426 for (OverloadedFunctionDecl::function_iterator Con 1427 = Constructors->function_begin(); 1428 Con != Constructors->function_end(); ++Con) { 1429 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 1430 if ((Kind == IK_Direct) || 1431 (Kind == IK_Copy && Constructor->isConvertingConstructor()) || 1432 (Kind == IK_Default && Constructor->isDefaultConstructor())) 1433 AddOverloadCandidate(Constructor, Args, NumArgs, CandidateSet); 1434 } 1435 1436 OverloadCandidateSet::iterator Best; 1437 switch (BestViableFunction(CandidateSet, Best)) { 1438 case OR_Success: 1439 // We found a constructor. Return it. 1440 return cast<CXXConstructorDecl>(Best->Function); 1441 1442 case OR_No_Viable_Function: 1443 if (CandidateSet.empty()) 1444 Diag(Loc, diag::err_ovl_no_viable_function_in_init, 1445 InitEntity, Range); 1446 else { 1447 Diag(Loc, diag::err_ovl_no_viable_function_in_init_with_cands, 1448 InitEntity, Range); 1449 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1450 } 1451 return 0; 1452 1453 case OR_Ambiguous: 1454 Diag(Loc, diag::err_ovl_ambiguous_init, 1455 InitEntity, Range); 1456 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1457 return 0; 1458 } 1459 1460 return 0; 1461} 1462 1463/// CompareReferenceRelationship - Compare the two types T1 and T2 to 1464/// determine whether they are reference-related, 1465/// reference-compatible, reference-compatible with added 1466/// qualification, or incompatible, for use in C++ initialization by 1467/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 1468/// type, and the first type (T1) is the pointee type of the reference 1469/// type being initialized. 1470Sema::ReferenceCompareResult 1471Sema::CompareReferenceRelationship(QualType T1, QualType T2, 1472 bool& DerivedToBase) { 1473 assert(!T1->isReferenceType() && "T1 must be the pointee type of the reference type"); 1474 assert(!T2->isReferenceType() && "T2 cannot be a reference type"); 1475 1476 T1 = Context.getCanonicalType(T1); 1477 T2 = Context.getCanonicalType(T2); 1478 QualType UnqualT1 = T1.getUnqualifiedType(); 1479 QualType UnqualT2 = T2.getUnqualifiedType(); 1480 1481 // C++ [dcl.init.ref]p4: 1482 // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is 1483 // reference-related to “cv2 T2” if T1 is the same type as T2, or 1484 // T1 is a base class of T2. 1485 if (UnqualT1 == UnqualT2) 1486 DerivedToBase = false; 1487 else if (IsDerivedFrom(UnqualT2, UnqualT1)) 1488 DerivedToBase = true; 1489 else 1490 return Ref_Incompatible; 1491 1492 // At this point, we know that T1 and T2 are reference-related (at 1493 // least). 1494 1495 // C++ [dcl.init.ref]p4: 1496 // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is 1497 // reference-related to T2 and cv1 is the same cv-qualification 1498 // as, or greater cv-qualification than, cv2. For purposes of 1499 // overload resolution, cases for which cv1 is greater 1500 // cv-qualification than cv2 are identified as 1501 // reference-compatible with added qualification (see 13.3.3.2). 1502 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 1503 return Ref_Compatible; 1504 else if (T1.isMoreQualifiedThan(T2)) 1505 return Ref_Compatible_With_Added_Qualification; 1506 else 1507 return Ref_Related; 1508} 1509 1510/// CheckReferenceInit - Check the initialization of a reference 1511/// variable with the given initializer (C++ [dcl.init.ref]). Init is 1512/// the initializer (either a simple initializer or an initializer 1513/// list), and DeclType is the type of the declaration. When ICS is 1514/// non-null, this routine will compute the implicit conversion 1515/// sequence according to C++ [over.ics.ref] and will not produce any 1516/// diagnostics; when ICS is null, it will emit diagnostics when any 1517/// errors are found. Either way, a return value of true indicates 1518/// that there was a failure, a return value of false indicates that 1519/// the reference initialization succeeded. 1520/// 1521/// When @p SuppressUserConversions, user-defined conversions are 1522/// suppressed. 1523bool 1524Sema::CheckReferenceInit(Expr *&Init, QualType &DeclType, 1525 ImplicitConversionSequence *ICS, 1526 bool SuppressUserConversions) { 1527 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 1528 1529 QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); 1530 QualType T2 = Init->getType(); 1531 1532 // If the initializer is the address of an overloaded function, try 1533 // to resolve the overloaded function. If all goes well, T2 is the 1534 // type of the resulting function. 1535 if (T2->isOverloadType()) { 1536 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Init, DeclType, 1537 ICS != 0); 1538 if (Fn) { 1539 // Since we're performing this reference-initialization for 1540 // real, update the initializer with the resulting function. 1541 if (!ICS) 1542 FixOverloadedFunctionReference(Init, Fn); 1543 1544 T2 = Fn->getType(); 1545 } 1546 } 1547 1548 // Compute some basic properties of the types and the initializer. 1549 bool DerivedToBase = false; 1550 Expr::isLvalueResult InitLvalue = Init->isLvalue(Context); 1551 ReferenceCompareResult RefRelationship 1552 = CompareReferenceRelationship(T1, T2, DerivedToBase); 1553 1554 // Most paths end in a failed conversion. 1555 if (ICS) 1556 ICS->ConversionKind = ImplicitConversionSequence::BadConversion; 1557 1558 // C++ [dcl.init.ref]p5: 1559 // A reference to type “cv1 T1” is initialized by an expression 1560 // of type “cv2 T2” as follows: 1561 1562 // -- If the initializer expression 1563 1564 bool BindsDirectly = false; 1565 // -- is an lvalue (but is not a bit-field), and “cv1 T1” is 1566 // reference-compatible with “cv2 T2,” or 1567 // 1568 // Note that the bit-field check is skipped if we are just computing 1569 // the implicit conversion sequence (C++ [over.best.ics]p2). 1570 if (InitLvalue == Expr::LV_Valid && (ICS || !Init->isBitField()) && 1571 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1572 BindsDirectly = true; 1573 1574 if (ICS) { 1575 // C++ [over.ics.ref]p1: 1576 // When a parameter of reference type binds directly (8.5.3) 1577 // to an argument expression, the implicit conversion sequence 1578 // is the identity conversion, unless the argument expression 1579 // has a type that is a derived class of the parameter type, 1580 // in which case the implicit conversion sequence is a 1581 // derived-to-base Conversion (13.3.3.1). 1582 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1583 ICS->Standard.First = ICK_Identity; 1584 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1585 ICS->Standard.Third = ICK_Identity; 1586 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1587 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1588 ICS->Standard.ReferenceBinding = true; 1589 ICS->Standard.DirectBinding = true; 1590 1591 // Nothing more to do: the inaccessibility/ambiguity check for 1592 // derived-to-base conversions is suppressed when we're 1593 // computing the implicit conversion sequence (C++ 1594 // [over.best.ics]p2). 1595 return false; 1596 } else { 1597 // Perform the conversion. 1598 // FIXME: Binding to a subobject of the lvalue is going to require 1599 // more AST annotation than this. 1600 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1601 } 1602 } 1603 1604 // -- has a class type (i.e., T2 is a class type) and can be 1605 // implicitly converted to an lvalue of type “cv3 T3,” 1606 // where “cv1 T1” is reference-compatible with “cv3 T3” 1607 // 92) (this conversion is selected by enumerating the 1608 // applicable conversion functions (13.3.1.6) and choosing 1609 // the best one through overload resolution (13.3)), 1610 if (!SuppressUserConversions && T2->isRecordType()) { 1611 // FIXME: Look for conversions in base classes! 1612 CXXRecordDecl *T2RecordDecl 1613 = dyn_cast<CXXRecordDecl>(T2->getAsRecordType()->getDecl()); 1614 1615 OverloadCandidateSet CandidateSet; 1616 OverloadedFunctionDecl *Conversions 1617 = T2RecordDecl->getConversionFunctions(); 1618 for (OverloadedFunctionDecl::function_iterator Func 1619 = Conversions->function_begin(); 1620 Func != Conversions->function_end(); ++Func) { 1621 CXXConversionDecl *Conv = cast<CXXConversionDecl>(*Func); 1622 1623 // If the conversion function doesn't return a reference type, 1624 // it can't be considered for this conversion. 1625 // FIXME: This will change when we support rvalue references. 1626 if (Conv->getConversionType()->isReferenceType()) 1627 AddConversionCandidate(Conv, Init, DeclType, CandidateSet); 1628 } 1629 1630 OverloadCandidateSet::iterator Best; 1631 switch (BestViableFunction(CandidateSet, Best)) { 1632 case OR_Success: 1633 // This is a direct binding. 1634 BindsDirectly = true; 1635 1636 if (ICS) { 1637 // C++ [over.ics.ref]p1: 1638 // 1639 // [...] If the parameter binds directly to the result of 1640 // applying a conversion function to the argument 1641 // expression, the implicit conversion sequence is a 1642 // user-defined conversion sequence (13.3.3.1.2), with the 1643 // second standard conversion sequence either an identity 1644 // conversion or, if the conversion function returns an 1645 // entity of a type that is a derived class of the parameter 1646 // type, a derived-to-base Conversion. 1647 ICS->ConversionKind = ImplicitConversionSequence::UserDefinedConversion; 1648 ICS->UserDefined.Before = Best->Conversions[0].Standard; 1649 ICS->UserDefined.After = Best->FinalConversion; 1650 ICS->UserDefined.ConversionFunction = Best->Function; 1651 assert(ICS->UserDefined.After.ReferenceBinding && 1652 ICS->UserDefined.After.DirectBinding && 1653 "Expected a direct reference binding!"); 1654 return false; 1655 } else { 1656 // Perform the conversion. 1657 // FIXME: Binding to a subobject of the lvalue is going to require 1658 // more AST annotation than this. 1659 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1660 } 1661 break; 1662 1663 case OR_Ambiguous: 1664 assert(false && "Ambiguous reference binding conversions not implemented."); 1665 return true; 1666 1667 case OR_No_Viable_Function: 1668 // There was no suitable conversion; continue with other checks. 1669 break; 1670 } 1671 } 1672 1673 if (BindsDirectly) { 1674 // C++ [dcl.init.ref]p4: 1675 // [...] In all cases where the reference-related or 1676 // reference-compatible relationship of two types is used to 1677 // establish the validity of a reference binding, and T1 is a 1678 // base class of T2, a program that necessitates such a binding 1679 // is ill-formed if T1 is an inaccessible (clause 11) or 1680 // ambiguous (10.2) base class of T2. 1681 // 1682 // Note that we only check this condition when we're allowed to 1683 // complain about errors, because we should not be checking for 1684 // ambiguity (or inaccessibility) unless the reference binding 1685 // actually happens. 1686 if (DerivedToBase) 1687 return CheckDerivedToBaseConversion(T2, T1, 1688 Init->getSourceRange().getBegin(), 1689 Init->getSourceRange()); 1690 else 1691 return false; 1692 } 1693 1694 // -- Otherwise, the reference shall be to a non-volatile const 1695 // type (i.e., cv1 shall be const). 1696 if (T1.getCVRQualifiers() != QualType::Const) { 1697 if (!ICS) 1698 Diag(Init->getSourceRange().getBegin(), 1699 diag::err_not_reference_to_const_init, 1700 T1.getAsString(), 1701 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1702 T2.getAsString(), Init->getSourceRange()); 1703 return true; 1704 } 1705 1706 // -- If the initializer expression is an rvalue, with T2 a 1707 // class type, and “cv1 T1” is reference-compatible with 1708 // “cv2 T2,” the reference is bound in one of the 1709 // following ways (the choice is implementation-defined): 1710 // 1711 // -- The reference is bound to the object represented by 1712 // the rvalue (see 3.10) or to a sub-object within that 1713 // object. 1714 // 1715 // -- A temporary of type “cv1 T2” [sic] is created, and 1716 // a constructor is called to copy the entire rvalue 1717 // object into the temporary. The reference is bound to 1718 // the temporary or to a sub-object within the 1719 // temporary. 1720 // 1721 // 1722 // The constructor that would be used to make the copy 1723 // shall be callable whether or not the copy is actually 1724 // done. 1725 // 1726 // Note that C++0x [dcl.ref.init]p5 takes away this implementation 1727 // freedom, so we will always take the first option and never build 1728 // a temporary in this case. FIXME: We will, however, have to check 1729 // for the presence of a copy constructor in C++98/03 mode. 1730 if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && 1731 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1732 if (ICS) { 1733 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1734 ICS->Standard.First = ICK_Identity; 1735 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1736 ICS->Standard.Third = ICK_Identity; 1737 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1738 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1739 ICS->Standard.ReferenceBinding = true; 1740 ICS->Standard.DirectBinding = false; 1741 } else { 1742 // FIXME: Binding to a subobject of the rvalue is going to require 1743 // more AST annotation than this. 1744 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1745 } 1746 return false; 1747 } 1748 1749 // -- Otherwise, a temporary of type “cv1 T1” is created and 1750 // initialized from the initializer expression using the 1751 // rules for a non-reference copy initialization (8.5). The 1752 // reference is then bound to the temporary. If T1 is 1753 // reference-related to T2, cv1 must be the same 1754 // cv-qualification as, or greater cv-qualification than, 1755 // cv2; otherwise, the program is ill-formed. 1756 if (RefRelationship == Ref_Related) { 1757 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 1758 // we would be reference-compatible or reference-compatible with 1759 // added qualification. But that wasn't the case, so the reference 1760 // initialization fails. 1761 if (!ICS) 1762 Diag(Init->getSourceRange().getBegin(), 1763 diag::err_reference_init_drops_quals, 1764 T1.getAsString(), 1765 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1766 T2.getAsString(), Init->getSourceRange()); 1767 return true; 1768 } 1769 1770 // Actually try to convert the initializer to T1. 1771 if (ICS) { 1772 /// C++ [over.ics.ref]p2: 1773 /// 1774 /// When a parameter of reference type is not bound directly to 1775 /// an argument expression, the conversion sequence is the one 1776 /// required to convert the argument expression to the 1777 /// underlying type of the reference according to 1778 /// 13.3.3.1. Conceptually, this conversion sequence corresponds 1779 /// to copy-initializing a temporary of the underlying type with 1780 /// the argument expression. Any difference in top-level 1781 /// cv-qualification is subsumed by the initialization itself 1782 /// and does not constitute a conversion. 1783 *ICS = TryImplicitConversion(Init, T1, SuppressUserConversions); 1784 return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; 1785 } else { 1786 return PerformImplicitConversion(Init, T1); 1787 } 1788} 1789 1790/// CheckOverloadedOperatorDeclaration - Check whether the declaration 1791/// of this overloaded operator is well-formed. If so, returns false; 1792/// otherwise, emits appropriate diagnostics and returns true. 1793bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) { 1794 assert(FnDecl && FnDecl->getOverloadedOperator() != OO_None && 1795 "Expected an overloaded operator declaration"); 1796 1797 bool IsInvalid = false; 1798 1799 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator(); 1800 1801 // C++ [over.oper]p5: 1802 // The allocation and deallocation functions, operator new, 1803 // operator new[], operator delete and operator delete[], are 1804 // described completely in 3.7.3. The attributes and restrictions 1805 // found in the rest of this subclause do not apply to them unless 1806 // explicitly stated in 3.7.3. 1807 // FIXME: Write a separate routine for checking this. For now, just 1808 // allow it. 1809 if (Op == OO_New || Op == OO_Array_New || 1810 Op == OO_Delete || Op == OO_Array_Delete) 1811 return false; 1812 1813 // C++ [over.oper]p6: 1814 // An operator function shall either be a non-static member 1815 // function or be a non-member function and have at least one 1816 // parameter whose type is a class, a reference to a class, an 1817 // enumeration, or a reference to an enumeration. 1818 CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl); 1819 if (MethodDecl) { 1820 if (MethodDecl->isStatic()) { 1821 Diag(FnDecl->getLocation(), 1822 diag::err_operator_overload_static, 1823 FnDecl->getName(), 1824 SourceRange(FnDecl->getLocation())); 1825 IsInvalid = true; 1826 1827 // Pretend this isn't a member function; it'll supress 1828 // additional, unnecessary error messages. 1829 MethodDecl = 0; 1830 } 1831 } else { 1832 bool ClassOrEnumParam = false; 1833 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 1834 Param != FnDecl->param_end(); ++Param) { 1835 QualType ParamType = (*Param)->getType(); 1836 if (const ReferenceType *RefType = ParamType->getAsReferenceType()) 1837 ParamType = RefType->getPointeeType(); 1838 if (ParamType->isRecordType() || ParamType->isEnumeralType()) { 1839 ClassOrEnumParam = true; 1840 break; 1841 } 1842 } 1843 1844 if (!ClassOrEnumParam) { 1845 Diag(FnDecl->getLocation(), 1846 diag::err_operator_overload_needs_class_or_enum, 1847 FnDecl->getName(), 1848 SourceRange(FnDecl->getLocation())); 1849 IsInvalid = true; 1850 } 1851 } 1852 1853 // C++ [over.oper]p8: 1854 // An operator function cannot have default arguments (8.3.6), 1855 // except where explicitly stated below. 1856 // 1857 // Only the function-call operator allows default arguments 1858 // (C++ [over.call]p1). 1859 if (Op != OO_Call) { 1860 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 1861 Param != FnDecl->param_end(); ++Param) { 1862 if (Expr *DefArg = (*Param)->getDefaultArg()) { 1863 Diag((*Param)->getLocation(), 1864 diag::err_operator_overload_default_arg, 1865 DefArg->getSourceRange()); 1866 IsInvalid = true; 1867 } 1868 } 1869 } 1870 1871 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = { 1872 { false, false, false } 1873#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \ 1874 , { Unary, Binary, MemberOnly } 1875#include "clang/Basic/OperatorKinds.def" 1876 }; 1877 1878 bool CanBeUnaryOperator = OperatorUses[Op][0]; 1879 bool CanBeBinaryOperator = OperatorUses[Op][1]; 1880 bool MustBeMemberOperator = OperatorUses[Op][2]; 1881 1882 // C++ [over.oper]p8: 1883 // [...] Operator functions cannot have more or fewer parameters 1884 // than the number required for the corresponding operator, as 1885 // described in the rest of this subclause. 1886 unsigned NumParams = FnDecl->getNumParams() + (MethodDecl? 1 : 0); 1887 if (Op != OO_Call && 1888 ((NumParams == 1 && !CanBeUnaryOperator) || 1889 (NumParams == 2 && !CanBeBinaryOperator) || 1890 (NumParams < 1) || (NumParams > 2))) { 1891 // We have the wrong number of parameters. 1892 std::string NumParamsStr = (llvm::APSInt(32) = NumParams).toString(10); 1893 1894 diag::kind DK; 1895 1896 if (CanBeUnaryOperator && CanBeBinaryOperator) { 1897 if (NumParams == 1) 1898 DK = diag::err_operator_overload_must_be_unary_or_binary; 1899 else 1900 DK = diag::err_operator_overload_must_be_unary_or_binary; 1901 } else if (CanBeUnaryOperator) { 1902 if (NumParams == 1) 1903 DK = diag::err_operator_overload_must_be_unary; 1904 else 1905 DK = diag::err_operator_overload_must_be_unary_plural; 1906 } else if (CanBeBinaryOperator) { 1907 if (NumParams == 1) 1908 DK = diag::err_operator_overload_must_be_binary; 1909 else 1910 DK = diag::err_operator_overload_must_be_binary_plural; 1911 } else { 1912 assert(false && "All non-call overloaded operators are unary or binary!"); 1913 } 1914 1915 Diag(FnDecl->getLocation(), DK, 1916 FnDecl->getName(), NumParamsStr, 1917 SourceRange(FnDecl->getLocation())); 1918 IsInvalid = true; 1919 } 1920 1921 // Overloaded operators cannot be variadic. 1922 if (FnDecl->getType()->getAsFunctionTypeProto()->isVariadic()) { 1923 Diag(FnDecl->getLocation(), 1924 diag::err_operator_overload_variadic, 1925 SourceRange(FnDecl->getLocation())); 1926 IsInvalid = true; 1927 } 1928 1929 // Some operators must be non-static member functions. 1930 if (MustBeMemberOperator && !MethodDecl) { 1931 Diag(FnDecl->getLocation(), 1932 diag::err_operator_overload_must_be_member, 1933 FnDecl->getName(), 1934 SourceRange(FnDecl->getLocation())); 1935 IsInvalid = true; 1936 } 1937 1938 // C++ [over.inc]p1: 1939 // The user-defined function called operator++ implements the 1940 // prefix and postfix ++ operator. If this function is a member 1941 // function with no parameters, or a non-member function with one 1942 // parameter of class or enumeration type, it defines the prefix 1943 // increment operator ++ for objects of that type. If the function 1944 // is a member function with one parameter (which shall be of type 1945 // int) or a non-member function with two parameters (the second 1946 // of which shall be of type int), it defines the postfix 1947 // increment operator ++ for objects of that type. 1948 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) { 1949 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1); 1950 bool ParamIsInt = false; 1951 if (const BuiltinType *BT = LastParam->getType()->getAsBuiltinType()) 1952 ParamIsInt = BT->getKind() == BuiltinType::Int; 1953 1954 if (!ParamIsInt) { 1955 diag::kind DK; 1956 if (Op == OO_PlusPlus) { 1957 if (MethodDecl) 1958 DK = diag::err_operator_overload_post_inc_must_be_int_member; 1959 else 1960 DK = diag::err_operator_overload_post_inc_must_be_int; 1961 } else { 1962 if (MethodDecl) 1963 DK = diag::err_operator_overload_post_dec_must_be_int_member; 1964 else 1965 DK = diag::err_operator_overload_post_dec_must_be_int; 1966 } 1967 Diag(LastParam->getLocation(), DK, 1968 Context.getCanonicalType(LastParam->getType()).getAsString(), 1969 SourceRange(FnDecl->getLocation())); 1970 IsInvalid = true; 1971 } 1972 } 1973 1974 return IsInvalid; 1975} 1976