SemaDeclCXX.cpp revision eb83ecde1a822b1c38cd060a85a08c1ac9f82cf8
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 if (CXXRecordDecl *CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext)) 268 return &II == CurDecl->getIdentifier(); 269 else 270 return false; 271} 272 273/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is 274/// one entry in the base class list of a class specifier, for 275/// example: 276/// class foo : public bar, virtual private baz { 277/// 'public bar' and 'virtual private baz' are each base-specifiers. 278Sema::BaseResult 279Sema::ActOnBaseSpecifier(DeclTy *classdecl, SourceRange SpecifierRange, 280 bool Virtual, AccessSpecifier Access, 281 TypeTy *basetype, SourceLocation BaseLoc) { 282 RecordDecl *Decl = (RecordDecl*)classdecl; 283 QualType BaseType = Context.getTypeDeclType((TypeDecl*)basetype); 284 285 // Base specifiers must be record types. 286 if (!BaseType->isRecordType()) { 287 Diag(BaseLoc, diag::err_base_must_be_class, SpecifierRange); 288 return true; 289 } 290 291 // C++ [class.union]p1: 292 // A union shall not be used as a base class. 293 if (BaseType->isUnionType()) { 294 Diag(BaseLoc, diag::err_union_as_base_class, SpecifierRange); 295 return true; 296 } 297 298 // C++ [class.union]p1: 299 // A union shall not have base classes. 300 if (Decl->isUnion()) { 301 Diag(Decl->getLocation(), diag::err_base_clause_on_union, 302 SpecifierRange); 303 return true; 304 } 305 306 // C++ [class.derived]p2: 307 // The class-name in a base-specifier shall not be an incompletely 308 // defined class. 309 if (BaseType->isIncompleteType()) { 310 Diag(BaseLoc, diag::err_incomplete_base_class, SpecifierRange); 311 return true; 312 } 313 314 // If the base class is polymorphic, the new one is, too. 315 RecordDecl *BaseDecl = BaseType->getAsRecordType()->getDecl(); 316 assert(BaseDecl && "Record type has no declaration"); 317 BaseDecl = BaseDecl->getDefinition(Context); 318 assert(BaseDecl && "Base type is not incomplete, but has no definition"); 319 if (cast<CXXRecordDecl>(BaseDecl)->isPolymorphic()) { 320 cast<CXXRecordDecl>(Decl)->setPolymorphic(true); 321 } 322 323 // Create the base specifier. 324 return new CXXBaseSpecifier(SpecifierRange, Virtual, 325 BaseType->isClassType(), Access, BaseType); 326} 327 328/// ActOnBaseSpecifiers - Attach the given base specifiers to the 329/// class, after checking whether there are any duplicate base 330/// classes. 331void Sema::ActOnBaseSpecifiers(DeclTy *ClassDecl, BaseTy **Bases, 332 unsigned NumBases) { 333 if (NumBases == 0) 334 return; 335 336 // Used to keep track of which base types we have already seen, so 337 // that we can properly diagnose redundant direct base types. Note 338 // that the key is always the unqualified canonical type of the base 339 // class. 340 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes; 341 342 // Copy non-redundant base specifiers into permanent storage. 343 CXXBaseSpecifier **BaseSpecs = (CXXBaseSpecifier **)Bases; 344 unsigned NumGoodBases = 0; 345 for (unsigned idx = 0; idx < NumBases; ++idx) { 346 QualType NewBaseType 347 = Context.getCanonicalType(BaseSpecs[idx]->getType()); 348 NewBaseType = NewBaseType.getUnqualifiedType(); 349 350 if (KnownBaseTypes[NewBaseType]) { 351 // C++ [class.mi]p3: 352 // A class shall not be specified as a direct base class of a 353 // derived class more than once. 354 Diag(BaseSpecs[idx]->getSourceRange().getBegin(), 355 diag::err_duplicate_base_class, 356 KnownBaseTypes[NewBaseType]->getType().getAsString(), 357 BaseSpecs[idx]->getSourceRange()); 358 359 // Delete the duplicate base class specifier; we're going to 360 // overwrite its pointer later. 361 delete BaseSpecs[idx]; 362 } else { 363 // Okay, add this new base class. 364 KnownBaseTypes[NewBaseType] = BaseSpecs[idx]; 365 BaseSpecs[NumGoodBases++] = BaseSpecs[idx]; 366 } 367 } 368 369 // Attach the remaining base class specifiers to the derived class. 370 CXXRecordDecl *Decl = (CXXRecordDecl*)ClassDecl; 371 Decl->setBases(BaseSpecs, NumGoodBases); 372 373 // Delete the remaining (good) base class specifiers, since their 374 // data has been copied into the CXXRecordDecl. 375 for (unsigned idx = 0; idx < NumGoodBases; ++idx) 376 delete BaseSpecs[idx]; 377} 378 379//===----------------------------------------------------------------------===// 380// C++ class member Handling 381//===----------------------------------------------------------------------===// 382 383/// ActOnStartCXXClassDef - This is called at the start of a class/struct/union 384/// definition, when on C++. 385void Sema::ActOnStartCXXClassDef(Scope *S, DeclTy *D, SourceLocation LBrace) { 386 CXXRecordDecl *Dcl = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 387 PushDeclContext(Dcl); 388 FieldCollector->StartClass(); 389 390 if (Dcl->getIdentifier()) { 391 // C++ [class]p2: 392 // [...] The class-name is also inserted into the scope of the 393 // class itself; this is known as the injected-class-name. For 394 // purposes of access checking, the injected-class-name is treated 395 // as if it were a public member name. 396 // FIXME: this should probably have its own kind of type node. 397 TypedefDecl *InjectedClassName 398 = TypedefDecl::Create(Context, Dcl, LBrace, Dcl->getIdentifier(), 399 Context.getTypeDeclType(Dcl), /*PrevDecl=*/0); 400 PushOnScopeChains(InjectedClassName, S); 401 } 402} 403 404/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member 405/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the 406/// bitfield width if there is one and 'InitExpr' specifies the initializer if 407/// any. 'LastInGroup' is non-null for cases where one declspec has multiple 408/// declarators on it. 409/// 410/// NOTE: Because of CXXFieldDecl's inability to be chained like ScopedDecls, if 411/// an instance field is declared, a new CXXFieldDecl is created but the method 412/// does *not* return it; it returns LastInGroup instead. The other C++ members 413/// (which are all ScopedDecls) are returned after appending them to 414/// LastInGroup. 415Sema::DeclTy * 416Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D, 417 ExprTy *BW, ExprTy *InitExpr, 418 DeclTy *LastInGroup) { 419 const DeclSpec &DS = D.getDeclSpec(); 420 IdentifierInfo *II = D.getIdentifier(); 421 Expr *BitWidth = static_cast<Expr*>(BW); 422 Expr *Init = static_cast<Expr*>(InitExpr); 423 SourceLocation Loc = D.getIdentifierLoc(); 424 425 // C++ 9.2p6: A member shall not be declared to have automatic storage 426 // duration (auto, register) or with the extern storage-class-specifier. 427 switch (DS.getStorageClassSpec()) { 428 case DeclSpec::SCS_unspecified: 429 case DeclSpec::SCS_typedef: 430 case DeclSpec::SCS_static: 431 // FALL THROUGH. 432 break; 433 default: 434 if (DS.getStorageClassSpecLoc().isValid()) 435 Diag(DS.getStorageClassSpecLoc(), 436 diag::err_storageclass_invalid_for_member); 437 else 438 Diag(DS.getThreadSpecLoc(), diag::err_storageclass_invalid_for_member); 439 D.getMutableDeclSpec().ClearStorageClassSpecs(); 440 } 441 442 bool isFunc = D.isFunctionDeclarator(); 443 if (!isFunc && 444 D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_typedef && 445 D.getNumTypeObjects() == 0) { 446 // Check also for this case: 447 // 448 // typedef int f(); 449 // f a; 450 // 451 Decl *TD = static_cast<Decl *>(DS.getTypeRep()); 452 isFunc = Context.getTypeDeclType(cast<TypeDecl>(TD))->isFunctionType(); 453 } 454 455 bool isInstField = (DS.getStorageClassSpec() == DeclSpec::SCS_unspecified && 456 !isFunc); 457 458 Decl *Member; 459 bool InvalidDecl = false; 460 461 if (isInstField) 462 Member = static_cast<Decl*>(ActOnField(S, Loc, D, BitWidth)); 463 else 464 Member = static_cast<Decl*>(ActOnDeclarator(S, D, LastInGroup)); 465 466 if (!Member) return LastInGroup; 467 468 assert((II || isInstField) && "No identifier for non-field ?"); 469 470 // set/getAccess is not part of Decl's interface to avoid bloating it with C++ 471 // specific methods. Use a wrapper class that can be used with all C++ class 472 // member decls. 473 CXXClassMemberWrapper(Member).setAccess(AS); 474 475 // C++ [dcl.init.aggr]p1: 476 // An aggregate is an array or a class (clause 9) with [...] no 477 // private or protected non-static data members (clause 11). 478 if (isInstField && (AS == AS_private || AS == AS_protected)) 479 cast<CXXRecordDecl>(CurContext)->setAggregate(false); 480 481 if (DS.isVirtualSpecified()) { 482 if (!isFunc || DS.getStorageClassSpec() == DeclSpec::SCS_static) { 483 Diag(DS.getVirtualSpecLoc(), diag::err_virtual_non_function); 484 InvalidDecl = true; 485 } else { 486 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(CurContext); 487 CurClass->setAggregate(false); 488 CurClass->setPolymorphic(true); 489 } 490 } 491 492 if (BitWidth) { 493 // C++ 9.6p2: Only when declaring an unnamed bit-field may the 494 // constant-expression be a value equal to zero. 495 // FIXME: Check this. 496 497 if (D.isFunctionDeclarator()) { 498 // FIXME: Emit diagnostic about only constructors taking base initializers 499 // or something similar, when constructor support is in place. 500 Diag(Loc, diag::err_not_bitfield_type, 501 II->getName(), BitWidth->getSourceRange()); 502 InvalidDecl = true; 503 504 } else if (isInstField) { 505 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 506 if (!cast<FieldDecl>(Member)->getType()->isIntegralType()) { 507 Diag(Loc, diag::err_not_integral_type_bitfield, 508 II->getName(), BitWidth->getSourceRange()); 509 InvalidDecl = true; 510 } 511 512 } else if (isa<FunctionDecl>(Member)) { 513 // A function typedef ("typedef int f(); f a;"). 514 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 515 Diag(Loc, diag::err_not_integral_type_bitfield, 516 II->getName(), BitWidth->getSourceRange()); 517 InvalidDecl = true; 518 519 } else if (isa<TypedefDecl>(Member)) { 520 // "cannot declare 'A' to be a bit-field type" 521 Diag(Loc, diag::err_not_bitfield_type, II->getName(), 522 BitWidth->getSourceRange()); 523 InvalidDecl = true; 524 525 } else { 526 assert(isa<CXXClassVarDecl>(Member) && 527 "Didn't we cover all member kinds?"); 528 // C++ 9.6p3: A bit-field shall not be a static member. 529 // "static member 'A' cannot be a bit-field" 530 Diag(Loc, diag::err_static_not_bitfield, II->getName(), 531 BitWidth->getSourceRange()); 532 InvalidDecl = true; 533 } 534 } 535 536 if (Init) { 537 // C++ 9.2p4: A member-declarator can contain a constant-initializer only 538 // if it declares a static member of const integral or const enumeration 539 // type. 540 if (CXXClassVarDecl *CVD = dyn_cast<CXXClassVarDecl>(Member)) { 541 // ...static member of... 542 CVD->setInit(Init); 543 // ...const integral or const enumeration type. 544 if (Context.getCanonicalType(CVD->getType()).isConstQualified() && 545 CVD->getType()->isIntegralType()) { 546 // constant-initializer 547 if (CheckForConstantInitializer(Init, CVD->getType())) 548 InvalidDecl = true; 549 550 } else { 551 // not const integral. 552 Diag(Loc, diag::err_member_initialization, 553 II->getName(), Init->getSourceRange()); 554 InvalidDecl = true; 555 } 556 557 } else { 558 // not static member. 559 Diag(Loc, diag::err_member_initialization, 560 II->getName(), Init->getSourceRange()); 561 InvalidDecl = true; 562 } 563 } 564 565 if (InvalidDecl) 566 Member->setInvalidDecl(); 567 568 if (isInstField) { 569 FieldCollector->Add(cast<CXXFieldDecl>(Member)); 570 return LastInGroup; 571 } 572 return Member; 573} 574 575/// ActOnMemInitializer - Handle a C++ member initializer. 576Sema::MemInitResult 577Sema::ActOnMemInitializer(DeclTy *ConstructorD, 578 Scope *S, 579 IdentifierInfo *MemberOrBase, 580 SourceLocation IdLoc, 581 SourceLocation LParenLoc, 582 ExprTy **Args, unsigned NumArgs, 583 SourceLocation *CommaLocs, 584 SourceLocation RParenLoc) { 585 CXXConstructorDecl *Constructor 586 = dyn_cast<CXXConstructorDecl>((Decl*)ConstructorD); 587 if (!Constructor) { 588 // The user wrote a constructor initializer on a function that is 589 // not a C++ constructor. Ignore the error for now, because we may 590 // have more member initializers coming; we'll diagnose it just 591 // once in ActOnMemInitializers. 592 return true; 593 } 594 595 CXXRecordDecl *ClassDecl = Constructor->getParent(); 596 597 // C++ [class.base.init]p2: 598 // Names in a mem-initializer-id are looked up in the scope of the 599 // constructor’s class and, if not found in that scope, are looked 600 // up in the scope containing the constructor’s 601 // definition. [Note: if the constructor’s class contains a member 602 // with the same name as a direct or virtual base class of the 603 // class, a mem-initializer-id naming the member or base class and 604 // composed of a single identifier refers to the class member. A 605 // mem-initializer-id for the hidden base class may be specified 606 // using a qualified name. ] 607 // Look for a member, first. 608 CXXFieldDecl *Member = ClassDecl->getMember(MemberOrBase); 609 610 // FIXME: Handle members of an anonymous union. 611 612 if (Member) { 613 // FIXME: Perform direct initialization of the member. 614 return new CXXBaseOrMemberInitializer(Member, (Expr **)Args, NumArgs); 615 } 616 617 // It didn't name a member, so see if it names a class. 618 TypeTy *BaseTy = isTypeName(*MemberOrBase, S, 0/*SS*/); 619 if (!BaseTy) 620 return Diag(IdLoc, diag::err_mem_init_not_member_or_class, 621 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 622 623 QualType BaseType = Context.getTypeDeclType((TypeDecl *)BaseTy); 624 if (!BaseType->isRecordType()) 625 return Diag(IdLoc, diag::err_base_init_does_not_name_class, 626 BaseType.getAsString(), SourceRange(IdLoc, RParenLoc)); 627 628 // C++ [class.base.init]p2: 629 // [...] Unless the mem-initializer-id names a nonstatic data 630 // member of the constructor’s class or a direct or virtual base 631 // of that class, the mem-initializer is ill-formed. A 632 // mem-initializer-list can initialize a base class using any 633 // name that denotes that base class type. 634 635 // First, check for a direct base class. 636 const CXXBaseSpecifier *DirectBaseSpec = 0; 637 for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin(); 638 Base != ClassDecl->bases_end(); ++Base) { 639 if (Context.getCanonicalType(BaseType).getUnqualifiedType() == 640 Context.getCanonicalType(Base->getType()).getUnqualifiedType()) { 641 // We found a direct base of this type. That's what we're 642 // initializing. 643 DirectBaseSpec = &*Base; 644 break; 645 } 646 } 647 648 // Check for a virtual base class. 649 // FIXME: We might be able to short-circuit this if we know in 650 // advance that there are no virtual bases. 651 const CXXBaseSpecifier *VirtualBaseSpec = 0; 652 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) { 653 // We haven't found a base yet; search the class hierarchy for a 654 // virtual base class. 655 BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 656 /*DetectVirtual=*/false); 657 if (IsDerivedFrom(Context.getTypeDeclType(ClassDecl), BaseType, Paths)) { 658 for (BasePaths::paths_iterator Path = Paths.begin(); 659 Path != Paths.end(); ++Path) { 660 if (Path->back().Base->isVirtual()) { 661 VirtualBaseSpec = Path->back().Base; 662 break; 663 } 664 } 665 } 666 } 667 668 // C++ [base.class.init]p2: 669 // If a mem-initializer-id is ambiguous because it designates both 670 // a direct non-virtual base class and an inherited virtual base 671 // class, the mem-initializer is ill-formed. 672 if (DirectBaseSpec && VirtualBaseSpec) 673 return Diag(IdLoc, diag::err_base_init_direct_and_virtual, 674 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 675 676 return new CXXBaseOrMemberInitializer(BaseType, (Expr **)Args, NumArgs); 677} 678 679 680void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc, 681 DeclTy *TagDecl, 682 SourceLocation LBrac, 683 SourceLocation RBrac) { 684 ActOnFields(S, RLoc, TagDecl, 685 (DeclTy**)FieldCollector->getCurFields(), 686 FieldCollector->getCurNumFields(), LBrac, RBrac, 0); 687} 688 689/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared 690/// special functions, such as the default constructor, copy 691/// constructor, or destructor, to the given C++ class (C++ 692/// [special]p1). This routine can only be executed just before the 693/// definition of the class is complete. 694void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) { 695 if (!ClassDecl->hasUserDeclaredConstructor()) { 696 // C++ [class.ctor]p5: 697 // A default constructor for a class X is a constructor of class X 698 // that can be called without an argument. If there is no 699 // user-declared constructor for class X, a default constructor is 700 // implicitly declared. An implicitly-declared default constructor 701 // is an inline public member of its class. 702 CXXConstructorDecl *DefaultCon = 703 CXXConstructorDecl::Create(Context, ClassDecl, 704 ClassDecl->getLocation(), 705 ClassDecl->getIdentifier(), 706 Context.getFunctionType(Context.VoidTy, 707 0, 0, false, 0), 708 /*isExplicit=*/false, 709 /*isInline=*/true, 710 /*isImplicitlyDeclared=*/true); 711 DefaultCon->setAccess(AS_public); 712 ClassDecl->addConstructor(Context, DefaultCon); 713 } 714 715 if (!ClassDecl->hasUserDeclaredCopyConstructor()) { 716 // C++ [class.copy]p4: 717 // If the class definition does not explicitly declare a copy 718 // constructor, one is declared implicitly. 719 720 // C++ [class.copy]p5: 721 // The implicitly-declared copy constructor for a class X will 722 // have the form 723 // 724 // X::X(const X&) 725 // 726 // if 727 bool HasConstCopyConstructor = true; 728 729 // -- each direct or virtual base class B of X has a copy 730 // constructor whose first parameter is of type const B& or 731 // const volatile B&, and 732 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 733 HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { 734 const CXXRecordDecl *BaseClassDecl 735 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 736 HasConstCopyConstructor 737 = BaseClassDecl->hasConstCopyConstructor(Context); 738 } 739 740 // -- for all the nonstatic data members of X that are of a 741 // class type M (or array thereof), each such class type 742 // has a copy constructor whose first parameter is of type 743 // const M& or const volatile M&. 744 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(); 745 HasConstCopyConstructor && Field != ClassDecl->field_end(); ++Field) { 746 QualType FieldType = (*Field)->getType(); 747 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 748 FieldType = Array->getElementType(); 749 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 750 const CXXRecordDecl *FieldClassDecl 751 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 752 HasConstCopyConstructor 753 = FieldClassDecl->hasConstCopyConstructor(Context); 754 } 755 } 756 757 // Otherwise, the implicitly declared copy constructor will have 758 // the form 759 // 760 // X::X(X&) 761 QualType ArgType = Context.getTypeDeclType(ClassDecl); 762 if (HasConstCopyConstructor) 763 ArgType = ArgType.withConst(); 764 ArgType = Context.getReferenceType(ArgType); 765 766 // An implicitly-declared copy constructor is an inline public 767 // member of its class. 768 CXXConstructorDecl *CopyConstructor 769 = CXXConstructorDecl::Create(Context, ClassDecl, 770 ClassDecl->getLocation(), 771 ClassDecl->getIdentifier(), 772 Context.getFunctionType(Context.VoidTy, 773 &ArgType, 1, 774 false, 0), 775 /*isExplicit=*/false, 776 /*isInline=*/true, 777 /*isImplicitlyDeclared=*/true); 778 CopyConstructor->setAccess(AS_public); 779 780 // Add the parameter to the constructor. 781 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, 782 ClassDecl->getLocation(), 783 /*IdentifierInfo=*/0, 784 ArgType, VarDecl::None, 0, 0); 785 CopyConstructor->setParams(&FromParam, 1); 786 787 ClassDecl->addConstructor(Context, CopyConstructor); 788 } 789 790 if (!ClassDecl->getDestructor()) { 791 // C++ [class.dtor]p2: 792 // If a class has no user-declared destructor, a destructor is 793 // declared implicitly. An implicitly-declared destructor is an 794 // inline public member of its class. 795 std::string DestructorName = "~"; 796 DestructorName += ClassDecl->getName(); 797 CXXDestructorDecl *Destructor 798 = CXXDestructorDecl::Create(Context, ClassDecl, 799 ClassDecl->getLocation(), 800 &PP.getIdentifierTable().get(DestructorName), 801 Context.getFunctionType(Context.VoidTy, 802 0, 0, false, 0), 803 /*isInline=*/true, 804 /*isImplicitlyDeclared=*/true); 805 Destructor->setAccess(AS_public); 806 ClassDecl->setDestructor(Destructor); 807 } 808 809 // FIXME: Implicit copy assignment operator 810} 811 812void Sema::ActOnFinishCXXClassDef(DeclTy *D) { 813 CXXRecordDecl *Rec = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 814 FieldCollector->FinishClass(); 815 AddImplicitlyDeclaredMembersToClass(Rec); 816 PopDeclContext(); 817 818 // Everything, including inline method definitions, have been parsed. 819 // Let the consumer know of the new TagDecl definition. 820 Consumer.HandleTagDeclDefinition(Rec); 821} 822 823/// CheckConstructorDeclarator - Called by ActOnDeclarator to check 824/// the well-formednes of the constructor declarator @p D with type @p 825/// R. If there are any errors in the declarator, this routine will 826/// emit diagnostics and return true. Otherwise, it will return 827/// false. Either way, the type @p R will be updated to reflect a 828/// well-formed type for the constructor. 829bool Sema::CheckConstructorDeclarator(Declarator &D, QualType &R, 830 FunctionDecl::StorageClass& SC) { 831 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 832 bool isInvalid = false; 833 834 // C++ [class.ctor]p3: 835 // A constructor shall not be virtual (10.3) or static (9.4). A 836 // constructor can be invoked for a const, volatile or const 837 // volatile object. A constructor shall not be declared const, 838 // volatile, or const volatile (9.3.2). 839 if (isVirtual) { 840 Diag(D.getIdentifierLoc(), 841 diag::err_constructor_cannot_be, 842 "virtual", 843 SourceRange(D.getDeclSpec().getVirtualSpecLoc()), 844 SourceRange(D.getIdentifierLoc())); 845 isInvalid = true; 846 } 847 if (SC == FunctionDecl::Static) { 848 Diag(D.getIdentifierLoc(), 849 diag::err_constructor_cannot_be, 850 "static", 851 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 852 SourceRange(D.getIdentifierLoc())); 853 isInvalid = true; 854 SC = FunctionDecl::None; 855 } 856 if (D.getDeclSpec().hasTypeSpecifier()) { 857 // Constructors don't have return types, but the parser will 858 // happily parse something like: 859 // 860 // class X { 861 // float X(float); 862 // }; 863 // 864 // The return type will be eliminated later. 865 Diag(D.getIdentifierLoc(), 866 diag::err_constructor_return_type, 867 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 868 SourceRange(D.getIdentifierLoc())); 869 } 870 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 871 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 872 if (FTI.TypeQuals & QualType::Const) 873 Diag(D.getIdentifierLoc(), 874 diag::err_invalid_qualified_constructor, 875 "const", 876 SourceRange(D.getIdentifierLoc())); 877 if (FTI.TypeQuals & QualType::Volatile) 878 Diag(D.getIdentifierLoc(), 879 diag::err_invalid_qualified_constructor, 880 "volatile", 881 SourceRange(D.getIdentifierLoc())); 882 if (FTI.TypeQuals & QualType::Restrict) 883 Diag(D.getIdentifierLoc(), 884 diag::err_invalid_qualified_constructor, 885 "restrict", 886 SourceRange(D.getIdentifierLoc())); 887 } 888 889 // Rebuild the function type "R" without any type qualifiers (in 890 // case any of the errors above fired) and with "void" as the 891 // return type, since constructors don't have return types. We 892 // *always* have to do this, because GetTypeForDeclarator will 893 // put in a result type of "int" when none was specified. 894 const FunctionTypeProto *Proto = R->getAsFunctionTypeProto(); 895 R = Context.getFunctionType(Context.VoidTy, Proto->arg_type_begin(), 896 Proto->getNumArgs(), 897 Proto->isVariadic(), 898 0); 899 900 return isInvalid; 901} 902 903/// CheckDestructorDeclarator - Called by ActOnDeclarator to check 904/// the well-formednes of the destructor declarator @p D with type @p 905/// R. If there are any errors in the declarator, this routine will 906/// emit diagnostics and return true. Otherwise, it will return 907/// false. Either way, the type @p R will be updated to reflect a 908/// well-formed type for the destructor. 909bool Sema::CheckDestructorDeclarator(Declarator &D, QualType &R, 910 FunctionDecl::StorageClass& SC) { 911 bool isInvalid = false; 912 913 // C++ [class.dtor]p1: 914 // [...] A typedef-name that names a class is a class-name 915 // (7.1.3); however, a typedef-name that names a class shall not 916 // be used as the identifier in the declarator for a destructor 917 // declaration. 918 TypeDecl *DeclaratorTypeD = (TypeDecl *)D.getDeclaratorIdType(); 919 if (const TypedefDecl *TypedefD = dyn_cast<TypedefDecl>(DeclaratorTypeD)) { 920 if (TypedefD->getIdentifier() != 921 cast<CXXRecordDecl>(CurContext)->getIdentifier()) { 922 // FIXME: This would be easier if we could just look at whether 923 // we found the injected-class-name. 924 Diag(D.getIdentifierLoc(), 925 diag::err_destructor_typedef_name, 926 TypedefD->getName()); 927 isInvalid = true; 928 } 929 } 930 931 // C++ [class.dtor]p2: 932 // A destructor is used to destroy objects of its class type. A 933 // destructor takes no parameters, and no return type can be 934 // specified for it (not even void). The address of a destructor 935 // shall not be taken. A destructor shall not be static. A 936 // destructor can be invoked for a const, volatile or const 937 // volatile object. A destructor shall not be declared const, 938 // volatile or const volatile (9.3.2). 939 if (SC == FunctionDecl::Static) { 940 Diag(D.getIdentifierLoc(), 941 diag::err_destructor_cannot_be, 942 "static", 943 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 944 SourceRange(D.getIdentifierLoc())); 945 isInvalid = true; 946 SC = FunctionDecl::None; 947 } 948 if (D.getDeclSpec().hasTypeSpecifier()) { 949 // Destructors don't have return types, but the parser will 950 // happily parse something like: 951 // 952 // class X { 953 // float ~X(); 954 // }; 955 // 956 // The return type will be eliminated later. 957 Diag(D.getIdentifierLoc(), 958 diag::err_destructor_return_type, 959 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 960 SourceRange(D.getIdentifierLoc())); 961 } 962 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 963 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 964 if (FTI.TypeQuals & QualType::Const) 965 Diag(D.getIdentifierLoc(), 966 diag::err_invalid_qualified_destructor, 967 "const", 968 SourceRange(D.getIdentifierLoc())); 969 if (FTI.TypeQuals & QualType::Volatile) 970 Diag(D.getIdentifierLoc(), 971 diag::err_invalid_qualified_destructor, 972 "volatile", 973 SourceRange(D.getIdentifierLoc())); 974 if (FTI.TypeQuals & QualType::Restrict) 975 Diag(D.getIdentifierLoc(), 976 diag::err_invalid_qualified_destructor, 977 "restrict", 978 SourceRange(D.getIdentifierLoc())); 979 } 980 981 // Make sure we don't have any parameters. 982 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 983 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params); 984 985 // Delete the parameters. 986 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 987 if (FTI.NumArgs) { 988 delete [] FTI.ArgInfo; 989 FTI.NumArgs = 0; 990 FTI.ArgInfo = 0; 991 } 992 } 993 994 // Make sure the destructor isn't variadic. 995 if (R->getAsFunctionTypeProto()->isVariadic()) 996 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic); 997 998 // Rebuild the function type "R" without any type qualifiers or 999 // parameters (in case any of the errors above fired) and with 1000 // "void" as the return type, since destructors don't have return 1001 // types. We *always* have to do this, because GetTypeForDeclarator 1002 // will put in a result type of "int" when none was specified. 1003 R = Context.getFunctionType(Context.VoidTy, 0, 0, false, 0); 1004 1005 return isInvalid; 1006} 1007 1008/// CheckConversionDeclarator - Called by ActOnDeclarator to check the 1009/// well-formednes of the conversion function declarator @p D with 1010/// type @p R. If there are any errors in the declarator, this routine 1011/// will emit diagnostics and return true. Otherwise, it will return 1012/// false. Either way, the type @p R will be updated to reflect a 1013/// well-formed type for the conversion operator. 1014bool Sema::CheckConversionDeclarator(Declarator &D, QualType &R, 1015 FunctionDecl::StorageClass& SC) { 1016 bool isInvalid = false; 1017 1018 // C++ [class.conv.fct]p1: 1019 // Neither parameter types nor return type can be specified. The 1020 // type of a conversion function (8.3.5) is “function taking no 1021 // parameter returning conversion-type-id.” 1022 if (SC == FunctionDecl::Static) { 1023 Diag(D.getIdentifierLoc(), 1024 diag::err_conv_function_not_member, 1025 "static", 1026 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 1027 SourceRange(D.getIdentifierLoc())); 1028 isInvalid = true; 1029 SC = FunctionDecl::None; 1030 } 1031 if (D.getDeclSpec().hasTypeSpecifier()) { 1032 // Conversion functions don't have return types, but the parser will 1033 // happily parse something like: 1034 // 1035 // class X { 1036 // float operator bool(); 1037 // }; 1038 // 1039 // The return type will be changed later anyway. 1040 Diag(D.getIdentifierLoc(), 1041 diag::err_conv_function_return_type, 1042 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 1043 SourceRange(D.getIdentifierLoc())); 1044 } 1045 1046 // Make sure we don't have any parameters. 1047 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 1048 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params); 1049 1050 // Delete the parameters. 1051 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1052 if (FTI.NumArgs) { 1053 delete [] FTI.ArgInfo; 1054 FTI.NumArgs = 0; 1055 FTI.ArgInfo = 0; 1056 } 1057 } 1058 1059 // Make sure the conversion function isn't variadic. 1060 if (R->getAsFunctionTypeProto()->isVariadic()) 1061 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic); 1062 1063 // C++ [class.conv.fct]p4: 1064 // The conversion-type-id shall not represent a function type nor 1065 // an array type. 1066 QualType ConvType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1067 if (ConvType->isArrayType()) { 1068 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array); 1069 ConvType = Context.getPointerType(ConvType); 1070 } else if (ConvType->isFunctionType()) { 1071 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function); 1072 ConvType = Context.getPointerType(ConvType); 1073 } 1074 1075 // Rebuild the function type "R" without any parameters (in case any 1076 // of the errors above fired) and with the conversion type as the 1077 // return type. 1078 R = Context.getFunctionType(ConvType, 0, 0, false, 1079 R->getAsFunctionTypeProto()->getTypeQuals()); 1080 1081 return isInvalid; 1082} 1083 1084/// ActOnConstructorDeclarator - Called by ActOnDeclarator to complete 1085/// the declaration of the given C++ constructor ConDecl that was 1086/// built from declarator D. This routine is responsible for checking 1087/// that the newly-created constructor declaration is well-formed and 1088/// for recording it in the C++ class. Example: 1089/// 1090/// @code 1091/// class X { 1092/// X(); // X::X() will be the ConDecl. 1093/// }; 1094/// @endcode 1095Sema::DeclTy *Sema::ActOnConstructorDeclarator(CXXConstructorDecl *ConDecl) { 1096 assert(ConDecl && "Expected to receive a constructor declaration"); 1097 1098 // Check default arguments on the constructor 1099 CheckCXXDefaultArguments(ConDecl); 1100 1101 CXXRecordDecl *ClassDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 1102 if (!ClassDecl) { 1103 ConDecl->setInvalidDecl(); 1104 return ConDecl; 1105 } 1106 1107 // Make sure this constructor is an overload of the existing 1108 // constructors. 1109 OverloadedFunctionDecl::function_iterator MatchedDecl; 1110 if (!IsOverload(ConDecl, ClassDecl->getConstructors(), MatchedDecl)) { 1111 Diag(ConDecl->getLocation(), 1112 diag::err_constructor_redeclared, 1113 SourceRange(ConDecl->getLocation())); 1114 Diag((*MatchedDecl)->getLocation(), 1115 diag::err_previous_declaration, 1116 SourceRange((*MatchedDecl)->getLocation())); 1117 ConDecl->setInvalidDecl(); 1118 return ConDecl; 1119 } 1120 1121 1122 // C++ [class.copy]p3: 1123 // A declaration of a constructor for a class X is ill-formed if 1124 // its first parameter is of type (optionally cv-qualified) X and 1125 // either there are no other parameters or else all other 1126 // parameters have default arguments. 1127 if ((ConDecl->getNumParams() == 1) || 1128 (ConDecl->getNumParams() > 1 && 1129 ConDecl->getParamDecl(1)->getDefaultArg() != 0)) { 1130 QualType ParamType = ConDecl->getParamDecl(0)->getType(); 1131 QualType ClassTy = Context.getTagDeclType( 1132 const_cast<CXXRecordDecl*>(ConDecl->getParent())); 1133 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { 1134 Diag(ConDecl->getLocation(), 1135 diag::err_constructor_byvalue_arg, 1136 SourceRange(ConDecl->getParamDecl(0)->getLocation())); 1137 ConDecl->setInvalidDecl(); 1138 return ConDecl; 1139 } 1140 } 1141 1142 // Add this constructor to the set of constructors of the current 1143 // class. 1144 ClassDecl->addConstructor(Context, ConDecl); 1145 return (DeclTy *)ConDecl; 1146} 1147 1148/// ActOnDestructorDeclarator - Called by ActOnDeclarator to complete 1149/// the declaration of the given C++ @p Destructor. This routine is 1150/// responsible for recording the destructor in the C++ class, if 1151/// possible. 1152Sema::DeclTy *Sema::ActOnDestructorDeclarator(CXXDestructorDecl *Destructor) { 1153 assert(Destructor && "Expected to receive a destructor declaration"); 1154 1155 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1156 1157 // Make sure we aren't redeclaring the destructor. 1158 if (CXXDestructorDecl *PrevDestructor = ClassDecl->getDestructor()) { 1159 Diag(Destructor->getLocation(), diag::err_destructor_redeclared); 1160 Diag(PrevDestructor->getLocation(), 1161 PrevDestructor->isThisDeclarationADefinition()? 1162 diag::err_previous_definition 1163 : diag::err_previous_declaration); 1164 Destructor->setInvalidDecl(); 1165 return Destructor; 1166 } 1167 1168 ClassDecl->setDestructor(Destructor); 1169 return (DeclTy *)Destructor; 1170} 1171 1172/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete 1173/// the declaration of the given C++ conversion function. This routine 1174/// is responsible for recording the conversion function in the C++ 1175/// class, if possible. 1176Sema::DeclTy *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) { 1177 assert(Conversion && "Expected to receive a conversion function declaration"); 1178 1179 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1180 1181 // Make sure we aren't redeclaring the conversion function. 1182 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType()); 1183 OverloadedFunctionDecl *Conversions = ClassDecl->getConversionFunctions(); 1184 for (OverloadedFunctionDecl::function_iterator Func 1185 = Conversions->function_begin(); 1186 Func != Conversions->function_end(); ++Func) { 1187 CXXConversionDecl *OtherConv = cast<CXXConversionDecl>(*Func); 1188 if (ConvType == Context.getCanonicalType(OtherConv->getConversionType())) { 1189 Diag(Conversion->getLocation(), diag::err_conv_function_redeclared); 1190 Diag(OtherConv->getLocation(), 1191 OtherConv->isThisDeclarationADefinition()? 1192 diag::err_previous_definition 1193 : diag::err_previous_declaration); 1194 Conversion->setInvalidDecl(); 1195 return (DeclTy *)Conversion; 1196 } 1197 } 1198 1199 // C++ [class.conv.fct]p1: 1200 // [...] A conversion function is never used to convert a 1201 // (possibly cv-qualified) object to the (possibly cv-qualified) 1202 // same object type (or a reference to it), to a (possibly 1203 // cv-qualified) base class of that type (or a reference to it), 1204 // or to (possibly cv-qualified) void. 1205 // FIXME: Suppress this warning if the conversion function ends up 1206 // being a virtual function that overrides a virtual function in a 1207 // base class. 1208 QualType ClassType 1209 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl)); 1210 if (const ReferenceType *ConvTypeRef = ConvType->getAsReferenceType()) 1211 ConvType = ConvTypeRef->getPointeeType(); 1212 if (ConvType->isRecordType()) { 1213 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType(); 1214 if (ConvType == ClassType) 1215 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used, 1216 ClassType.getAsString()); 1217 else if (IsDerivedFrom(ClassType, ConvType)) 1218 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used, 1219 ClassType.getAsString(), 1220 ConvType.getAsString()); 1221 } else if (ConvType->isVoidType()) { 1222 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used, 1223 ClassType.getAsString(), ConvType.getAsString()); 1224 } 1225 1226 ClassDecl->addConversionFunction(Context, Conversion); 1227 1228 return (DeclTy *)Conversion; 1229} 1230 1231//===----------------------------------------------------------------------===// 1232// Namespace Handling 1233//===----------------------------------------------------------------------===// 1234 1235/// ActOnStartNamespaceDef - This is called at the start of a namespace 1236/// definition. 1237Sema::DeclTy *Sema::ActOnStartNamespaceDef(Scope *NamespcScope, 1238 SourceLocation IdentLoc, 1239 IdentifierInfo *II, 1240 SourceLocation LBrace) { 1241 NamespaceDecl *Namespc = 1242 NamespaceDecl::Create(Context, CurContext, IdentLoc, II); 1243 Namespc->setLBracLoc(LBrace); 1244 1245 Scope *DeclRegionScope = NamespcScope->getParent(); 1246 1247 if (II) { 1248 // C++ [namespace.def]p2: 1249 // The identifier in an original-namespace-definition shall not have been 1250 // previously defined in the declarative region in which the 1251 // original-namespace-definition appears. The identifier in an 1252 // original-namespace-definition is the name of the namespace. Subsequently 1253 // in that declarative region, it is treated as an original-namespace-name. 1254 1255 Decl *PrevDecl = 1256 LookupDecl(II, Decl::IDNS_Tag | Decl::IDNS_Ordinary, DeclRegionScope, 1257 /*enableLazyBuiltinCreation=*/false); 1258 1259 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, DeclRegionScope)) { 1260 if (NamespaceDecl *OrigNS = dyn_cast<NamespaceDecl>(PrevDecl)) { 1261 // This is an extended namespace definition. 1262 // Attach this namespace decl to the chain of extended namespace 1263 // definitions. 1264 NamespaceDecl *NextNS = OrigNS; 1265 while (NextNS->getNextNamespace()) 1266 NextNS = NextNS->getNextNamespace(); 1267 1268 NextNS->setNextNamespace(Namespc); 1269 Namespc->setOriginalNamespace(OrigNS); 1270 1271 // We won't add this decl to the current scope. We want the namespace 1272 // name to return the original namespace decl during a name lookup. 1273 } else { 1274 // This is an invalid name redefinition. 1275 Diag(Namespc->getLocation(), diag::err_redefinition_different_kind, 1276 Namespc->getName()); 1277 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1278 Namespc->setInvalidDecl(); 1279 // Continue on to push Namespc as current DeclContext and return it. 1280 } 1281 } else { 1282 // This namespace name is declared for the first time. 1283 PushOnScopeChains(Namespc, DeclRegionScope); 1284 } 1285 } 1286 else { 1287 // FIXME: Handle anonymous namespaces 1288 } 1289 1290 // Although we could have an invalid decl (i.e. the namespace name is a 1291 // redefinition), push it as current DeclContext and try to continue parsing. 1292 PushDeclContext(Namespc->getOriginalNamespace()); 1293 return Namespc; 1294} 1295 1296/// ActOnFinishNamespaceDef - This callback is called after a namespace is 1297/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. 1298void Sema::ActOnFinishNamespaceDef(DeclTy *D, SourceLocation RBrace) { 1299 Decl *Dcl = static_cast<Decl *>(D); 1300 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); 1301 assert(Namespc && "Invalid parameter, expected NamespaceDecl"); 1302 Namespc->setRBracLoc(RBrace); 1303 PopDeclContext(); 1304} 1305 1306 1307/// AddCXXDirectInitializerToDecl - This action is called immediately after 1308/// ActOnDeclarator, when a C++ direct initializer is present. 1309/// e.g: "int x(1);" 1310void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc, 1311 ExprTy **ExprTys, unsigned NumExprs, 1312 SourceLocation *CommaLocs, 1313 SourceLocation RParenLoc) { 1314 assert(NumExprs != 0 && ExprTys && "missing expressions"); 1315 Decl *RealDecl = static_cast<Decl *>(Dcl); 1316 1317 // If there is no declaration, there was an error parsing it. Just ignore 1318 // the initializer. 1319 if (RealDecl == 0) { 1320 for (unsigned i = 0; i != NumExprs; ++i) 1321 delete static_cast<Expr *>(ExprTys[i]); 1322 return; 1323 } 1324 1325 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1326 if (!VDecl) { 1327 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 1328 RealDecl->setInvalidDecl(); 1329 return; 1330 } 1331 1332 // We will treat direct-initialization as a copy-initialization: 1333 // int x(1); -as-> int x = 1; 1334 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); 1335 // 1336 // Clients that want to distinguish between the two forms, can check for 1337 // direct initializer using VarDecl::hasCXXDirectInitializer(). 1338 // A major benefit is that clients that don't particularly care about which 1339 // exactly form was it (like the CodeGen) can handle both cases without 1340 // special case code. 1341 1342 // C++ 8.5p11: 1343 // The form of initialization (using parentheses or '=') is generally 1344 // insignificant, but does matter when the entity being initialized has a 1345 // class type. 1346 QualType DeclInitType = VDecl->getType(); 1347 if (const ArrayType *Array = Context.getAsArrayType(DeclInitType)) 1348 DeclInitType = Array->getElementType(); 1349 1350 if (VDecl->getType()->isRecordType()) { 1351 CXXConstructorDecl *Constructor 1352 = PerformInitializationByConstructor(DeclInitType, 1353 (Expr **)ExprTys, NumExprs, 1354 VDecl->getLocation(), 1355 SourceRange(VDecl->getLocation(), 1356 RParenLoc), 1357 VDecl->getName(), 1358 IK_Direct); 1359 if (!Constructor) { 1360 RealDecl->setInvalidDecl(); 1361 } 1362 1363 // Let clients know that initialization was done with a direct 1364 // initializer. 1365 VDecl->setCXXDirectInitializer(true); 1366 1367 // FIXME: Add ExprTys and Constructor to the RealDecl as part of 1368 // the initializer. 1369 return; 1370 } 1371 1372 if (NumExprs > 1) { 1373 Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg, 1374 SourceRange(VDecl->getLocation(), RParenLoc)); 1375 RealDecl->setInvalidDecl(); 1376 return; 1377 } 1378 1379 // Let clients know that initialization was done with a direct initializer. 1380 VDecl->setCXXDirectInitializer(true); 1381 1382 assert(NumExprs == 1 && "Expected 1 expression"); 1383 // Set the init expression, handles conversions. 1384 AddInitializerToDecl(Dcl, ExprTys[0]); 1385} 1386 1387/// PerformInitializationByConstructor - Perform initialization by 1388/// constructor (C++ [dcl.init]p14), which may occur as part of 1389/// direct-initialization or copy-initialization. We are initializing 1390/// an object of type @p ClassType with the given arguments @p 1391/// Args. @p Loc is the location in the source code where the 1392/// initializer occurs (e.g., a declaration, member initializer, 1393/// functional cast, etc.) while @p Range covers the whole 1394/// initialization. @p InitEntity is the entity being initialized, 1395/// which may by the name of a declaration or a type. @p Kind is the 1396/// kind of initialization we're performing, which affects whether 1397/// explicit constructors will be considered. When successful, returns 1398/// the constructor that will be used to perform the initialization; 1399/// when the initialization fails, emits a diagnostic and returns 1400/// null. 1401CXXConstructorDecl * 1402Sema::PerformInitializationByConstructor(QualType ClassType, 1403 Expr **Args, unsigned NumArgs, 1404 SourceLocation Loc, SourceRange Range, 1405 std::string InitEntity, 1406 InitializationKind Kind) { 1407 const RecordType *ClassRec = ClassType->getAsRecordType(); 1408 assert(ClassRec && "Can only initialize a class type here"); 1409 1410 // C++ [dcl.init]p14: 1411 // 1412 // If the initialization is direct-initialization, or if it is 1413 // copy-initialization where the cv-unqualified version of the 1414 // source type is the same class as, or a derived class of, the 1415 // class of the destination, constructors are considered. The 1416 // applicable constructors are enumerated (13.3.1.3), and the 1417 // best one is chosen through overload resolution (13.3). The 1418 // constructor so selected is called to initialize the object, 1419 // with the initializer expression(s) as its argument(s). If no 1420 // constructor applies, or the overload resolution is ambiguous, 1421 // the initialization is ill-formed. 1422 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1423 OverloadCandidateSet CandidateSet; 1424 1425 // Add constructors to the overload set. 1426 OverloadedFunctionDecl *Constructors 1427 = const_cast<OverloadedFunctionDecl *>(ClassDecl->getConstructors()); 1428 for (OverloadedFunctionDecl::function_iterator Con 1429 = Constructors->function_begin(); 1430 Con != Constructors->function_end(); ++Con) { 1431 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 1432 if ((Kind == IK_Direct) || 1433 (Kind == IK_Copy && Constructor->isConvertingConstructor()) || 1434 (Kind == IK_Default && Constructor->isDefaultConstructor())) 1435 AddOverloadCandidate(Constructor, Args, NumArgs, CandidateSet); 1436 } 1437 1438 OverloadCandidateSet::iterator Best; 1439 switch (BestViableFunction(CandidateSet, Best)) { 1440 case OR_Success: 1441 // We found a constructor. Return it. 1442 return cast<CXXConstructorDecl>(Best->Function); 1443 1444 case OR_No_Viable_Function: 1445 if (CandidateSet.empty()) 1446 Diag(Loc, diag::err_ovl_no_viable_function_in_init, 1447 InitEntity, Range); 1448 else { 1449 Diag(Loc, diag::err_ovl_no_viable_function_in_init_with_cands, 1450 InitEntity, Range); 1451 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1452 } 1453 return 0; 1454 1455 case OR_Ambiguous: 1456 Diag(Loc, diag::err_ovl_ambiguous_init, 1457 InitEntity, Range); 1458 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1459 return 0; 1460 } 1461 1462 return 0; 1463} 1464 1465/// CompareReferenceRelationship - Compare the two types T1 and T2 to 1466/// determine whether they are reference-related, 1467/// reference-compatible, reference-compatible with added 1468/// qualification, or incompatible, for use in C++ initialization by 1469/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 1470/// type, and the first type (T1) is the pointee type of the reference 1471/// type being initialized. 1472Sema::ReferenceCompareResult 1473Sema::CompareReferenceRelationship(QualType T1, QualType T2, 1474 bool& DerivedToBase) { 1475 assert(!T1->isReferenceType() && "T1 must be the pointee type of the reference type"); 1476 assert(!T2->isReferenceType() && "T2 cannot be a reference type"); 1477 1478 T1 = Context.getCanonicalType(T1); 1479 T2 = Context.getCanonicalType(T2); 1480 QualType UnqualT1 = T1.getUnqualifiedType(); 1481 QualType UnqualT2 = T2.getUnqualifiedType(); 1482 1483 // C++ [dcl.init.ref]p4: 1484 // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is 1485 // reference-related to “cv2 T2” if T1 is the same type as T2, or 1486 // T1 is a base class of T2. 1487 if (UnqualT1 == UnqualT2) 1488 DerivedToBase = false; 1489 else if (IsDerivedFrom(UnqualT2, UnqualT1)) 1490 DerivedToBase = true; 1491 else 1492 return Ref_Incompatible; 1493 1494 // At this point, we know that T1 and T2 are reference-related (at 1495 // least). 1496 1497 // C++ [dcl.init.ref]p4: 1498 // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is 1499 // reference-related to T2 and cv1 is the same cv-qualification 1500 // as, or greater cv-qualification than, cv2. For purposes of 1501 // overload resolution, cases for which cv1 is greater 1502 // cv-qualification than cv2 are identified as 1503 // reference-compatible with added qualification (see 13.3.3.2). 1504 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 1505 return Ref_Compatible; 1506 else if (T1.isMoreQualifiedThan(T2)) 1507 return Ref_Compatible_With_Added_Qualification; 1508 else 1509 return Ref_Related; 1510} 1511 1512/// CheckReferenceInit - Check the initialization of a reference 1513/// variable with the given initializer (C++ [dcl.init.ref]). Init is 1514/// the initializer (either a simple initializer or an initializer 1515/// list), and DeclType is the type of the declaration. When ICS is 1516/// non-null, this routine will compute the implicit conversion 1517/// sequence according to C++ [over.ics.ref] and will not produce any 1518/// diagnostics; when ICS is null, it will emit diagnostics when any 1519/// errors are found. Either way, a return value of true indicates 1520/// that there was a failure, a return value of false indicates that 1521/// the reference initialization succeeded. 1522/// 1523/// When @p SuppressUserConversions, user-defined conversions are 1524/// suppressed. 1525bool 1526Sema::CheckReferenceInit(Expr *&Init, QualType &DeclType, 1527 ImplicitConversionSequence *ICS, 1528 bool SuppressUserConversions) { 1529 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 1530 1531 QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); 1532 QualType T2 = Init->getType(); 1533 1534 // Compute some basic properties of the types and the initializer. 1535 bool DerivedToBase = false; 1536 Expr::isLvalueResult InitLvalue = Init->isLvalue(Context); 1537 ReferenceCompareResult RefRelationship 1538 = CompareReferenceRelationship(T1, T2, DerivedToBase); 1539 1540 // Most paths end in a failed conversion. 1541 if (ICS) 1542 ICS->ConversionKind = ImplicitConversionSequence::BadConversion; 1543 1544 // C++ [dcl.init.ref]p5: 1545 // A reference to type “cv1 T1” is initialized by an expression 1546 // of type “cv2 T2” as follows: 1547 1548 // -- If the initializer expression 1549 1550 bool BindsDirectly = false; 1551 // -- is an lvalue (but is not a bit-field), and “cv1 T1” is 1552 // reference-compatible with “cv2 T2,” or 1553 // 1554 // Note that the bit-field check is skipped if we are just computing 1555 // the implicit conversion sequence (C++ [over.best.ics]p2). 1556 if (InitLvalue == Expr::LV_Valid && (ICS || !Init->isBitField()) && 1557 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1558 BindsDirectly = true; 1559 1560 if (ICS) { 1561 // C++ [over.ics.ref]p1: 1562 // When a parameter of reference type binds directly (8.5.3) 1563 // to an argument expression, the implicit conversion sequence 1564 // is the identity conversion, unless the argument expression 1565 // has a type that is a derived class of the parameter type, 1566 // in which case the implicit conversion sequence is a 1567 // derived-to-base Conversion (13.3.3.1). 1568 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1569 ICS->Standard.First = ICK_Identity; 1570 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1571 ICS->Standard.Third = ICK_Identity; 1572 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1573 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1574 ICS->Standard.ReferenceBinding = true; 1575 ICS->Standard.DirectBinding = true; 1576 1577 // Nothing more to do: the inaccessibility/ambiguity check for 1578 // derived-to-base conversions is suppressed when we're 1579 // computing the implicit conversion sequence (C++ 1580 // [over.best.ics]p2). 1581 return false; 1582 } else { 1583 // Perform the conversion. 1584 // FIXME: Binding to a subobject of the lvalue is going to require 1585 // more AST annotation than this. 1586 ImpCastExprToType(Init, T1); 1587 } 1588 } 1589 1590 // -- has a class type (i.e., T2 is a class type) and can be 1591 // implicitly converted to an lvalue of type “cv3 T3,” 1592 // where “cv1 T1” is reference-compatible with “cv3 T3” 1593 // 92) (this conversion is selected by enumerating the 1594 // applicable conversion functions (13.3.1.6) and choosing 1595 // the best one through overload resolution (13.3)), 1596 // FIXME: Implement this second bullet, once we have conversion 1597 // functions. Also remember C++ [over.ics.ref]p1, second part. 1598 1599 if (BindsDirectly) { 1600 // C++ [dcl.init.ref]p4: 1601 // [...] In all cases where the reference-related or 1602 // reference-compatible relationship of two types is used to 1603 // establish the validity of a reference binding, and T1 is a 1604 // base class of T2, a program that necessitates such a binding 1605 // is ill-formed if T1 is an inaccessible (clause 11) or 1606 // ambiguous (10.2) base class of T2. 1607 // 1608 // Note that we only check this condition when we're allowed to 1609 // complain about errors, because we should not be checking for 1610 // ambiguity (or inaccessibility) unless the reference binding 1611 // actually happens. 1612 if (DerivedToBase) 1613 return CheckDerivedToBaseConversion(T2, T1, 1614 Init->getSourceRange().getBegin(), 1615 Init->getSourceRange()); 1616 else 1617 return false; 1618 } 1619 1620 // -- Otherwise, the reference shall be to a non-volatile const 1621 // type (i.e., cv1 shall be const). 1622 if (T1.getCVRQualifiers() != QualType::Const) { 1623 if (!ICS) 1624 Diag(Init->getSourceRange().getBegin(), 1625 diag::err_not_reference_to_const_init, 1626 T1.getAsString(), 1627 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1628 T2.getAsString(), Init->getSourceRange()); 1629 return true; 1630 } 1631 1632 // -- If the initializer expression is an rvalue, with T2 a 1633 // class type, and “cv1 T1” is reference-compatible with 1634 // “cv2 T2,” the reference is bound in one of the 1635 // following ways (the choice is implementation-defined): 1636 // 1637 // -- The reference is bound to the object represented by 1638 // the rvalue (see 3.10) or to a sub-object within that 1639 // object. 1640 // 1641 // -- A temporary of type “cv1 T2” [sic] is created, and 1642 // a constructor is called to copy the entire rvalue 1643 // object into the temporary. The reference is bound to 1644 // the temporary or to a sub-object within the 1645 // temporary. 1646 // 1647 // 1648 // The constructor that would be used to make the copy 1649 // shall be callable whether or not the copy is actually 1650 // done. 1651 // 1652 // Note that C++0x [dcl.ref.init]p5 takes away this implementation 1653 // freedom, so we will always take the first option and never build 1654 // a temporary in this case. FIXME: We will, however, have to check 1655 // for the presence of a copy constructor in C++98/03 mode. 1656 if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && 1657 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1658 if (ICS) { 1659 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1660 ICS->Standard.First = ICK_Identity; 1661 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1662 ICS->Standard.Third = ICK_Identity; 1663 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1664 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1665 ICS->Standard.ReferenceBinding = true; 1666 ICS->Standard.DirectBinding = false; 1667 } else { 1668 // FIXME: Binding to a subobject of the rvalue is going to require 1669 // more AST annotation than this. 1670 ImpCastExprToType(Init, T1); 1671 } 1672 return false; 1673 } 1674 1675 // -- Otherwise, a temporary of type “cv1 T1” is created and 1676 // initialized from the initializer expression using the 1677 // rules for a non-reference copy initialization (8.5). The 1678 // reference is then bound to the temporary. If T1 is 1679 // reference-related to T2, cv1 must be the same 1680 // cv-qualification as, or greater cv-qualification than, 1681 // cv2; otherwise, the program is ill-formed. 1682 if (RefRelationship == Ref_Related) { 1683 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 1684 // we would be reference-compatible or reference-compatible with 1685 // added qualification. But that wasn't the case, so the reference 1686 // initialization fails. 1687 if (!ICS) 1688 Diag(Init->getSourceRange().getBegin(), 1689 diag::err_reference_init_drops_quals, 1690 T1.getAsString(), 1691 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1692 T2.getAsString(), Init->getSourceRange()); 1693 return true; 1694 } 1695 1696 // Actually try to convert the initializer to T1. 1697 if (ICS) { 1698 /// C++ [over.ics.ref]p2: 1699 /// 1700 /// When a parameter of reference type is not bound directly to 1701 /// an argument expression, the conversion sequence is the one 1702 /// required to convert the argument expression to the 1703 /// underlying type of the reference according to 1704 /// 13.3.3.1. Conceptually, this conversion sequence corresponds 1705 /// to copy-initializing a temporary of the underlying type with 1706 /// the argument expression. Any difference in top-level 1707 /// cv-qualification is subsumed by the initialization itself 1708 /// and does not constitute a conversion. 1709 *ICS = TryImplicitConversion(Init, T1, SuppressUserConversions); 1710 return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; 1711 } else { 1712 return PerformImplicitConversion(Init, T1); 1713 } 1714} 1715 1716/// CheckOverloadedOperatorDeclaration - Check whether the declaration 1717/// of this overloaded operator is well-formed. If so, returns false; 1718/// otherwise, emits appropriate diagnostics and returns true. 1719bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) { 1720 assert(FnDecl && FnDecl->getOverloadedOperator() != OO_None && 1721 "Expected an overloaded operator declaration"); 1722 1723 bool IsInvalid = false; 1724 1725 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator(); 1726 1727 // C++ [over.oper]p5: 1728 // The allocation and deallocation functions, operator new, 1729 // operator new[], operator delete and operator delete[], are 1730 // described completely in 3.7.3. The attributes and restrictions 1731 // found in the rest of this subclause do not apply to them unless 1732 // explicitly stated in 3.7.3. 1733 // FIXME: Write a separate routine for checking this. For now, just 1734 // allow it. 1735 if (Op == OO_New || Op == OO_Array_New || 1736 Op == OO_Delete || Op == OO_Array_Delete) 1737 return false; 1738 1739 // C++ [over.oper]p6: 1740 // An operator function shall either be a non-static member 1741 // function or be a non-member function and have at least one 1742 // parameter whose type is a class, a reference to a class, an 1743 // enumeration, or a reference to an enumeration. 1744 CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl); 1745 if (MethodDecl) { 1746 if (MethodDecl->isStatic()) { 1747 Diag(FnDecl->getLocation(), 1748 diag::err_operator_overload_static, 1749 FnDecl->getName(), 1750 SourceRange(FnDecl->getLocation())); 1751 IsInvalid = true; 1752 1753 // Pretend this isn't a member function; it'll supress 1754 // additional, unnecessary error messages. 1755 MethodDecl = 0; 1756 } 1757 } else { 1758 bool ClassOrEnumParam = false; 1759 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 1760 Param != FnDecl->param_end(); ++Param) { 1761 QualType ParamType = (*Param)->getType(); 1762 if (const ReferenceType *RefType = ParamType->getAsReferenceType()) 1763 ParamType = RefType->getPointeeType(); 1764 if (ParamType->isRecordType() || ParamType->isEnumeralType()) { 1765 ClassOrEnumParam = true; 1766 break; 1767 } 1768 } 1769 1770 if (!ClassOrEnumParam) { 1771 Diag(FnDecl->getLocation(), 1772 diag::err_operator_overload_needs_class_or_enum, 1773 FnDecl->getName(), 1774 SourceRange(FnDecl->getLocation())); 1775 IsInvalid = true; 1776 } 1777 } 1778 1779 // C++ [over.oper]p8: 1780 // An operator function cannot have default arguments (8.3.6), 1781 // except where explicitly stated below. 1782 // 1783 // Only the function-call operator allows default arguments 1784 // (C++ [over.call]p1). 1785 if (Op != OO_Call) { 1786 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 1787 Param != FnDecl->param_end(); ++Param) { 1788 if (Expr *DefArg = (*Param)->getDefaultArg()) { 1789 Diag((*Param)->getLocation(), 1790 diag::err_operator_overload_default_arg, 1791 DefArg->getSourceRange()); 1792 IsInvalid = true; 1793 } 1794 } 1795 } 1796 1797 bool CanBeUnaryOperator = false; 1798 bool CanBeBinaryOperator = false; 1799 bool MustBeMemberOperator = false; 1800 1801 switch (Op) { 1802 case OO_New: 1803 case OO_Delete: 1804 case OO_Array_New: 1805 case OO_Array_Delete: 1806 assert(false && "Operators new, new[], delete, and delete[] handled above"); 1807 return true; 1808 1809 // Unary-only operators 1810 case OO_Arrow: 1811 MustBeMemberOperator = true; 1812 // Fall through 1813 1814 case OO_Tilde: 1815 case OO_Exclaim: 1816 CanBeUnaryOperator = true; 1817 break; 1818 1819 // Binary-only operators 1820 case OO_Equal: 1821 case OO_Subscript: 1822 MustBeMemberOperator = true; 1823 // Fall through 1824 1825 case OO_Slash: 1826 case OO_Percent: 1827 case OO_Caret: 1828 case OO_Pipe: 1829 case OO_Less: 1830 case OO_Greater: 1831 case OO_PlusEqual: 1832 case OO_MinusEqual: 1833 case OO_StarEqual: 1834 case OO_SlashEqual: 1835 case OO_PercentEqual: 1836 case OO_CaretEqual: 1837 case OO_AmpEqual: 1838 case OO_PipeEqual: 1839 case OO_LessLess: 1840 case OO_GreaterGreater: 1841 case OO_LessLessEqual: 1842 case OO_GreaterGreaterEqual: 1843 case OO_EqualEqual: 1844 case OO_ExclaimEqual: 1845 case OO_LessEqual: 1846 case OO_GreaterEqual: 1847 case OO_AmpAmp: 1848 case OO_PipePipe: 1849 case OO_Comma: 1850 CanBeBinaryOperator = true; 1851 break; 1852 1853 // Unary or binary operators 1854 case OO_Amp: 1855 case OO_Plus: 1856 case OO_Minus: 1857 case OO_Star: 1858 case OO_PlusPlus: 1859 case OO_MinusMinus: 1860 case OO_ArrowStar: 1861 CanBeUnaryOperator = true; 1862 CanBeBinaryOperator = true; 1863 break; 1864 1865 case OO_Call: 1866 MustBeMemberOperator = true; 1867 break; 1868 1869 case OO_None: 1870 case NUM_OVERLOADED_OPERATORS: 1871 assert(false && "Not an overloaded operator!"); 1872 return true; 1873 } 1874 1875 // C++ [over.oper]p8: 1876 // [...] Operator functions cannot have more or fewer parameters 1877 // than the number required for the corresponding operator, as 1878 // described in the rest of this subclause. 1879 unsigned NumParams = FnDecl->getNumParams() + (MethodDecl? 1 : 0); 1880 if (Op != OO_Call && 1881 ((NumParams == 1 && !CanBeUnaryOperator) || 1882 (NumParams == 2 && !CanBeBinaryOperator) || 1883 (NumParams < 1) || (NumParams > 2))) { 1884 // We have the wrong number of parameters. 1885 std::string NumParamsStr = (llvm::APSInt(32) = NumParams).toString(10); 1886 std::string NumParamsPlural; 1887 if (NumParams != 1) 1888 NumParamsPlural = "s"; 1889 1890 diag::kind DK; 1891 1892 if (CanBeUnaryOperator && CanBeBinaryOperator) 1893 DK = diag::err_operator_overload_must_be_unary_or_binary; 1894 else if (CanBeUnaryOperator) 1895 DK = diag::err_operator_overload_must_be_unary; 1896 else if (CanBeBinaryOperator) 1897 DK = diag::err_operator_overload_must_be_binary; 1898 else 1899 assert(false && "All non-call overloaded operators are unary or binary!"); 1900 1901 Diag(FnDecl->getLocation(), DK, 1902 FnDecl->getName(), NumParamsStr, NumParamsPlural, 1903 SourceRange(FnDecl->getLocation())); 1904 IsInvalid = true; 1905 } 1906 1907 // Overloaded operators cannot be variadic. 1908 if (FnDecl->getType()->getAsFunctionTypeProto()->isVariadic()) { 1909 Diag(FnDecl->getLocation(), 1910 diag::err_operator_overload_variadic, 1911 SourceRange(FnDecl->getLocation())); 1912 IsInvalid = true; 1913 } 1914 1915 // Some operators must be non-static member functions. 1916 if (MustBeMemberOperator && !MethodDecl) { 1917 Diag(FnDecl->getLocation(), 1918 diag::err_operator_overload_must_be_member, 1919 FnDecl->getName(), 1920 SourceRange(FnDecl->getLocation())); 1921 IsInvalid = true; 1922 } 1923 1924 // C++ [over.inc]p1: 1925 // The user-defined function called operator++ implements the 1926 // prefix and postfix ++ operator. If this function is a member 1927 // function with no parameters, or a non-member function with one 1928 // parameter of class or enumeration type, it defines the prefix 1929 // increment operator ++ for objects of that type. If the function 1930 // is a member function with one parameter (which shall be of type 1931 // int) or a non-member function with two parameters (the second 1932 // of which shall be of type int), it defines the postfix 1933 // increment operator ++ for objects of that type. 1934 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) { 1935 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1); 1936 bool ParamIsInt = false; 1937 if (const BuiltinType *BT = LastParam->getType()->getAsBuiltinType()) 1938 ParamIsInt = BT->getKind() == BuiltinType::Int; 1939 1940 if (!ParamIsInt) { 1941 Diag(LastParam->getLocation(), 1942 diag::err_operator_overload_post_incdec_must_be_int, 1943 MethodDecl? std::string() : std::string("second "), 1944 (Op == OO_PlusPlus)? std::string("increment") 1945 : std::string("decrement"), 1946 Context.getCanonicalType(LastParam->getType()).getAsString(), 1947 SourceRange(FnDecl->getLocation())); 1948 IsInvalid = true; 1949 } 1950 } 1951 1952 return IsInvalid; 1953} 1954