SemaDeclCXX.cpp revision 9f5337b3f6c3871db5756b0f9ba0babc13c4eac7
1//===------ SemaDeclCXX.cpp - Semantic Analysis for C++ Declarations ------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file implements semantic analysis for C++ declarations. 11// 12//===----------------------------------------------------------------------===// 13 14#include "Sema.h" 15#include "SemaInherit.h" 16#include "clang/AST/ASTConsumer.h" 17#include "clang/AST/ASTContext.h" 18#include "clang/AST/TypeOrdering.h" 19#include "clang/AST/StmtVisitor.h" 20#include "clang/Lex/Preprocessor.h" 21#include "clang/Basic/Diagnostic.h" 22#include "clang/Parse/DeclSpec.h" 23#include "llvm/Support/Compiler.h" 24#include <algorithm> // for std::equal 25#include <map> 26 27using namespace clang; 28 29//===----------------------------------------------------------------------===// 30// CheckDefaultArgumentVisitor 31//===----------------------------------------------------------------------===// 32 33namespace { 34 /// CheckDefaultArgumentVisitor - C++ [dcl.fct.default] Traverses 35 /// the default argument of a parameter to determine whether it 36 /// contains any ill-formed subexpressions. For example, this will 37 /// diagnose the use of local variables or parameters within the 38 /// default argument expression. 39 class VISIBILITY_HIDDEN CheckDefaultArgumentVisitor 40 : public StmtVisitor<CheckDefaultArgumentVisitor, bool> { 41 Expr *DefaultArg; 42 Sema *S; 43 44 public: 45 CheckDefaultArgumentVisitor(Expr *defarg, Sema *s) 46 : DefaultArg(defarg), S(s) {} 47 48 bool VisitExpr(Expr *Node); 49 bool VisitDeclRefExpr(DeclRefExpr *DRE); 50 bool VisitCXXThisExpr(CXXThisExpr *ThisE); 51 }; 52 53 /// VisitExpr - Visit all of the children of this expression. 54 bool CheckDefaultArgumentVisitor::VisitExpr(Expr *Node) { 55 bool IsInvalid = false; 56 for (Stmt::child_iterator I = Node->child_begin(), 57 E = Node->child_end(); I != E; ++I) 58 IsInvalid |= Visit(*I); 59 return IsInvalid; 60 } 61 62 /// VisitDeclRefExpr - Visit a reference to a declaration, to 63 /// determine whether this declaration can be used in the default 64 /// argument expression. 65 bool CheckDefaultArgumentVisitor::VisitDeclRefExpr(DeclRefExpr *DRE) { 66 NamedDecl *Decl = DRE->getDecl(); 67 if (ParmVarDecl *Param = dyn_cast<ParmVarDecl>(Decl)) { 68 // C++ [dcl.fct.default]p9 69 // Default arguments are evaluated each time the function is 70 // called. The order of evaluation of function arguments is 71 // unspecified. Consequently, parameters of a function shall not 72 // be used in default argument expressions, even if they are not 73 // evaluated. Parameters of a function declared before a default 74 // argument expression are in scope and can hide namespace and 75 // class member names. 76 return S->Diag(DRE->getSourceRange().getBegin(), 77 diag::err_param_default_argument_references_param, 78 Param->getName(), DefaultArg->getSourceRange()); 79 } else if (VarDecl *VDecl = dyn_cast<VarDecl>(Decl)) { 80 // C++ [dcl.fct.default]p7 81 // Local variables shall not be used in default argument 82 // expressions. 83 if (VDecl->isBlockVarDecl()) 84 return S->Diag(DRE->getSourceRange().getBegin(), 85 diag::err_param_default_argument_references_local, 86 VDecl->getName(), DefaultArg->getSourceRange()); 87 } 88 89 return false; 90 } 91 92 /// VisitCXXThisExpr - Visit a C++ "this" expression. 93 bool CheckDefaultArgumentVisitor::VisitCXXThisExpr(CXXThisExpr *ThisE) { 94 // C++ [dcl.fct.default]p8: 95 // The keyword this shall not be used in a default argument of a 96 // member function. 97 return S->Diag(ThisE->getSourceRange().getBegin(), 98 diag::err_param_default_argument_references_this, 99 ThisE->getSourceRange()); 100 } 101} 102 103/// ActOnParamDefaultArgument - Check whether the default argument 104/// provided for a function parameter is well-formed. If so, attach it 105/// to the parameter declaration. 106void 107Sema::ActOnParamDefaultArgument(DeclTy *param, SourceLocation EqualLoc, 108 ExprTy *defarg) { 109 ParmVarDecl *Param = (ParmVarDecl *)param; 110 llvm::OwningPtr<Expr> DefaultArg((Expr *)defarg); 111 QualType ParamType = Param->getType(); 112 113 // Default arguments are only permitted in C++ 114 if (!getLangOptions().CPlusPlus) { 115 Diag(EqualLoc, diag::err_param_default_argument, 116 DefaultArg->getSourceRange()); 117 return; 118 } 119 120 // C++ [dcl.fct.default]p5 121 // A default argument expression is implicitly converted (clause 122 // 4) to the parameter type. The default argument expression has 123 // the same semantic constraints as the initializer expression in 124 // a declaration of a variable of the parameter type, using the 125 // copy-initialization semantics (8.5). 126 Expr *DefaultArgPtr = DefaultArg.get(); 127 bool DefaultInitFailed = PerformCopyInitialization(DefaultArgPtr, ParamType, 128 "in default argument"); 129 if (DefaultArgPtr != DefaultArg.get()) { 130 DefaultArg.take(); 131 DefaultArg.reset(DefaultArgPtr); 132 } 133 if (DefaultInitFailed) { 134 return; 135 } 136 137 // Check that the default argument is well-formed 138 CheckDefaultArgumentVisitor DefaultArgChecker(DefaultArg.get(), this); 139 if (DefaultArgChecker.Visit(DefaultArg.get())) 140 return; 141 142 // Okay: add the default argument to the parameter 143 Param->setDefaultArg(DefaultArg.take()); 144} 145 146/// CheckExtraCXXDefaultArguments - Check for any extra default 147/// arguments in the declarator, which is not a function declaration 148/// or definition and therefore is not permitted to have default 149/// arguments. This routine should be invoked for every declarator 150/// that is not a function declaration or definition. 151void Sema::CheckExtraCXXDefaultArguments(Declarator &D) { 152 // C++ [dcl.fct.default]p3 153 // A default argument expression shall be specified only in the 154 // parameter-declaration-clause of a function declaration or in a 155 // template-parameter (14.1). It shall not be specified for a 156 // parameter pack. If it is specified in a 157 // parameter-declaration-clause, it shall not occur within a 158 // declarator or abstract-declarator of a parameter-declaration. 159 for (unsigned i = 0; i < D.getNumTypeObjects(); ++i) { 160 DeclaratorChunk &chunk = D.getTypeObject(i); 161 if (chunk.Kind == DeclaratorChunk::Function) { 162 for (unsigned argIdx = 0; argIdx < chunk.Fun.NumArgs; ++argIdx) { 163 ParmVarDecl *Param = (ParmVarDecl *)chunk.Fun.ArgInfo[argIdx].Param; 164 if (Param->getDefaultArg()) { 165 Diag(Param->getLocation(), diag::err_param_default_argument_nonfunc, 166 Param->getDefaultArg()->getSourceRange()); 167 Param->setDefaultArg(0); 168 } 169 } 170 } 171 } 172} 173 174// MergeCXXFunctionDecl - Merge two declarations of the same C++ 175// function, once we already know that they have the same 176// type. Subroutine of MergeFunctionDecl. 177FunctionDecl * 178Sema::MergeCXXFunctionDecl(FunctionDecl *New, FunctionDecl *Old) { 179 // C++ [dcl.fct.default]p4: 180 // 181 // For non-template functions, default arguments can be added in 182 // later declarations of a function in the same 183 // scope. Declarations in different scopes have completely 184 // distinct sets of default arguments. That is, declarations in 185 // inner scopes do not acquire default arguments from 186 // declarations in outer scopes, and vice versa. In a given 187 // function declaration, all parameters subsequent to a 188 // parameter with a default argument shall have default 189 // arguments supplied in this or previous declarations. A 190 // default argument shall not be redefined by a later 191 // declaration (not even to the same value). 192 for (unsigned p = 0, NumParams = Old->getNumParams(); p < NumParams; ++p) { 193 ParmVarDecl *OldParam = Old->getParamDecl(p); 194 ParmVarDecl *NewParam = New->getParamDecl(p); 195 196 if(OldParam->getDefaultArg() && NewParam->getDefaultArg()) { 197 Diag(NewParam->getLocation(), 198 diag::err_param_default_argument_redefinition, 199 NewParam->getDefaultArg()->getSourceRange()); 200 Diag(OldParam->getLocation(), diag::err_previous_definition); 201 } else if (OldParam->getDefaultArg()) { 202 // Merge the old default argument into the new parameter 203 NewParam->setDefaultArg(OldParam->getDefaultArg()); 204 } 205 } 206 207 return New; 208} 209 210/// CheckCXXDefaultArguments - Verify that the default arguments for a 211/// function declaration are well-formed according to C++ 212/// [dcl.fct.default]. 213void Sema::CheckCXXDefaultArguments(FunctionDecl *FD) { 214 unsigned NumParams = FD->getNumParams(); 215 unsigned p; 216 217 // Find first parameter with a default argument 218 for (p = 0; p < NumParams; ++p) { 219 ParmVarDecl *Param = FD->getParamDecl(p); 220 if (Param->getDefaultArg()) 221 break; 222 } 223 224 // C++ [dcl.fct.default]p4: 225 // In a given function declaration, all parameters 226 // subsequent to a parameter with a default argument shall 227 // have default arguments supplied in this or previous 228 // declarations. A default argument shall not be redefined 229 // by a later declaration (not even to the same value). 230 unsigned LastMissingDefaultArg = 0; 231 for(; p < NumParams; ++p) { 232 ParmVarDecl *Param = FD->getParamDecl(p); 233 if (!Param->getDefaultArg()) { 234 if (Param->getIdentifier()) 235 Diag(Param->getLocation(), 236 diag::err_param_default_argument_missing_name, 237 Param->getIdentifier()->getName()); 238 else 239 Diag(Param->getLocation(), 240 diag::err_param_default_argument_missing); 241 242 LastMissingDefaultArg = p; 243 } 244 } 245 246 if (LastMissingDefaultArg > 0) { 247 // Some default arguments were missing. Clear out all of the 248 // default arguments up to (and including) the last missing 249 // default argument, so that we leave the function parameters 250 // in a semantically valid state. 251 for (p = 0; p <= LastMissingDefaultArg; ++p) { 252 ParmVarDecl *Param = FD->getParamDecl(p); 253 if (Param->getDefaultArg()) { 254 delete Param->getDefaultArg(); 255 Param->setDefaultArg(0); 256 } 257 } 258 } 259} 260 261/// isCurrentClassName - Determine whether the identifier II is the 262/// name of the class type currently being defined. In the case of 263/// nested classes, this will only return true if II is the name of 264/// the innermost class. 265bool Sema::isCurrentClassName(const IdentifierInfo &II, Scope *, 266 const CXXScopeSpec *SS) { 267 CXXRecordDecl *CurDecl; 268 if (SS) { 269 DeclContext *DC = static_cast<DeclContext*>(SS->getScopeRep()); 270 CurDecl = dyn_cast_or_null<CXXRecordDecl>(DC); 271 } else 272 CurDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 273 274 if (CurDecl) 275 return &II == CurDecl->getIdentifier(); 276 else 277 return false; 278} 279 280/// ActOnBaseSpecifier - Parsed a base specifier. A base specifier is 281/// one entry in the base class list of a class specifier, for 282/// example: 283/// class foo : public bar, virtual private baz { 284/// 'public bar' and 'virtual private baz' are each base-specifiers. 285Sema::BaseResult 286Sema::ActOnBaseSpecifier(DeclTy *classdecl, SourceRange SpecifierRange, 287 bool Virtual, AccessSpecifier Access, 288 TypeTy *basetype, SourceLocation BaseLoc) { 289 RecordDecl *Decl = (RecordDecl*)classdecl; 290 QualType BaseType = Context.getTypeDeclType((TypeDecl*)basetype); 291 292 // Base specifiers must be record types. 293 if (!BaseType->isRecordType()) { 294 Diag(BaseLoc, diag::err_base_must_be_class, SpecifierRange); 295 return true; 296 } 297 298 // C++ [class.union]p1: 299 // A union shall not be used as a base class. 300 if (BaseType->isUnionType()) { 301 Diag(BaseLoc, diag::err_union_as_base_class, SpecifierRange); 302 return true; 303 } 304 305 // C++ [class.union]p1: 306 // A union shall not have base classes. 307 if (Decl->isUnion()) { 308 Diag(Decl->getLocation(), diag::err_base_clause_on_union, 309 SpecifierRange); 310 return true; 311 } 312 313 // C++ [class.derived]p2: 314 // The class-name in a base-specifier shall not be an incompletely 315 // defined class. 316 if (BaseType->isIncompleteType()) { 317 Diag(BaseLoc, diag::err_incomplete_base_class, SpecifierRange); 318 return true; 319 } 320 321 // If the base class is polymorphic, the new one is, too. 322 RecordDecl *BaseDecl = BaseType->getAsRecordType()->getDecl(); 323 assert(BaseDecl && "Record type has no declaration"); 324 BaseDecl = BaseDecl->getDefinition(Context); 325 assert(BaseDecl && "Base type is not incomplete, but has no definition"); 326 if (cast<CXXRecordDecl>(BaseDecl)->isPolymorphic()) { 327 cast<CXXRecordDecl>(Decl)->setPolymorphic(true); 328 } 329 330 // Create the base specifier. 331 return new CXXBaseSpecifier(SpecifierRange, Virtual, 332 BaseType->isClassType(), Access, BaseType); 333} 334 335/// ActOnBaseSpecifiers - Attach the given base specifiers to the 336/// class, after checking whether there are any duplicate base 337/// classes. 338void Sema::ActOnBaseSpecifiers(DeclTy *ClassDecl, BaseTy **Bases, 339 unsigned NumBases) { 340 if (NumBases == 0) 341 return; 342 343 // Used to keep track of which base types we have already seen, so 344 // that we can properly diagnose redundant direct base types. Note 345 // that the key is always the unqualified canonical type of the base 346 // class. 347 std::map<QualType, CXXBaseSpecifier*, QualTypeOrdering> KnownBaseTypes; 348 349 // Copy non-redundant base specifiers into permanent storage. 350 CXXBaseSpecifier **BaseSpecs = (CXXBaseSpecifier **)Bases; 351 unsigned NumGoodBases = 0; 352 for (unsigned idx = 0; idx < NumBases; ++idx) { 353 QualType NewBaseType 354 = Context.getCanonicalType(BaseSpecs[idx]->getType()); 355 NewBaseType = NewBaseType.getUnqualifiedType(); 356 357 if (KnownBaseTypes[NewBaseType]) { 358 // C++ [class.mi]p3: 359 // A class shall not be specified as a direct base class of a 360 // derived class more than once. 361 Diag(BaseSpecs[idx]->getSourceRange().getBegin(), 362 diag::err_duplicate_base_class, 363 KnownBaseTypes[NewBaseType]->getType().getAsString(), 364 BaseSpecs[idx]->getSourceRange()); 365 366 // Delete the duplicate base class specifier; we're going to 367 // overwrite its pointer later. 368 delete BaseSpecs[idx]; 369 } else { 370 // Okay, add this new base class. 371 KnownBaseTypes[NewBaseType] = BaseSpecs[idx]; 372 BaseSpecs[NumGoodBases++] = BaseSpecs[idx]; 373 } 374 } 375 376 // Attach the remaining base class specifiers to the derived class. 377 CXXRecordDecl *Decl = (CXXRecordDecl*)ClassDecl; 378 Decl->setBases(BaseSpecs, NumGoodBases); 379 380 // Delete the remaining (good) base class specifiers, since their 381 // data has been copied into the CXXRecordDecl. 382 for (unsigned idx = 0; idx < NumGoodBases; ++idx) 383 delete BaseSpecs[idx]; 384} 385 386//===----------------------------------------------------------------------===// 387// C++ class member Handling 388//===----------------------------------------------------------------------===// 389 390/// ActOnStartCXXClassDef - This is called at the start of a class/struct/union 391/// definition, when on C++. 392void Sema::ActOnStartCXXClassDef(Scope *S, DeclTy *D, SourceLocation LBrace) { 393 CXXRecordDecl *Dcl = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 394 PushDeclContext(Dcl); 395 FieldCollector->StartClass(); 396 397 if (Dcl->getIdentifier()) { 398 // C++ [class]p2: 399 // [...] The class-name is also inserted into the scope of the 400 // class itself; this is known as the injected-class-name. For 401 // purposes of access checking, the injected-class-name is treated 402 // as if it were a public member name. 403 PushOnScopeChains(Dcl, S); 404 } 405} 406 407/// ActOnCXXMemberDeclarator - This is invoked when a C++ class member 408/// declarator is parsed. 'AS' is the access specifier, 'BW' specifies the 409/// bitfield width if there is one and 'InitExpr' specifies the initializer if 410/// any. 'LastInGroup' is non-null for cases where one declspec has multiple 411/// declarators on it. 412/// 413/// NOTE: Because of CXXFieldDecl's inability to be chained like ScopedDecls, if 414/// an instance field is declared, a new CXXFieldDecl is created but the method 415/// does *not* return it; it returns LastInGroup instead. The other C++ members 416/// (which are all ScopedDecls) are returned after appending them to 417/// LastInGroup. 418Sema::DeclTy * 419Sema::ActOnCXXMemberDeclarator(Scope *S, AccessSpecifier AS, Declarator &D, 420 ExprTy *BW, ExprTy *InitExpr, 421 DeclTy *LastInGroup) { 422 const DeclSpec &DS = D.getDeclSpec(); 423 IdentifierInfo *II = D.getIdentifier(); 424 Expr *BitWidth = static_cast<Expr*>(BW); 425 Expr *Init = static_cast<Expr*>(InitExpr); 426 SourceLocation Loc = D.getIdentifierLoc(); 427 428 bool isFunc = D.isFunctionDeclarator(); 429 430 // C++ 9.2p6: A member shall not be declared to have automatic storage 431 // duration (auto, register) or with the extern storage-class-specifier. 432 // C++ 7.1.1p8: The mutable specifier can be applied only to names of class 433 // data members and cannot be applied to names declared const or static, 434 // and cannot be applied to reference members. 435 switch (DS.getStorageClassSpec()) { 436 case DeclSpec::SCS_unspecified: 437 case DeclSpec::SCS_typedef: 438 case DeclSpec::SCS_static: 439 // FALL THROUGH. 440 break; 441 case DeclSpec::SCS_mutable: 442 if (isFunc) { 443 if (DS.getStorageClassSpecLoc().isValid()) 444 Diag(DS.getStorageClassSpecLoc(), 445 diag::err_mutable_function); 446 else 447 Diag(DS.getThreadSpecLoc(), 448 diag::err_mutable_function); 449 D.getMutableDeclSpec().ClearStorageClassSpecs(); 450 } else { 451 QualType T = GetTypeForDeclarator(D, S); 452 diag::kind err = static_cast<diag::kind>(0); 453 if (T->isReferenceType()) 454 err = diag::err_mutable_reference; 455 else if (T.isConstQualified()) 456 err = diag::err_mutable_const; 457 if (err != 0) { 458 if (DS.getStorageClassSpecLoc().isValid()) 459 Diag(DS.getStorageClassSpecLoc(), err); 460 else 461 Diag(DS.getThreadSpecLoc(), err); 462 D.getMutableDeclSpec().ClearStorageClassSpecs(); 463 } 464 } 465 break; 466 default: 467 if (DS.getStorageClassSpecLoc().isValid()) 468 Diag(DS.getStorageClassSpecLoc(), 469 diag::err_storageclass_invalid_for_member); 470 else 471 Diag(DS.getThreadSpecLoc(), diag::err_storageclass_invalid_for_member); 472 D.getMutableDeclSpec().ClearStorageClassSpecs(); 473 } 474 475 if (!isFunc && 476 D.getDeclSpec().getTypeSpecType() == DeclSpec::TST_typedef && 477 D.getNumTypeObjects() == 0) { 478 // Check also for this case: 479 // 480 // typedef int f(); 481 // f a; 482 // 483 Decl *TD = static_cast<Decl *>(DS.getTypeRep()); 484 isFunc = Context.getTypeDeclType(cast<TypeDecl>(TD))->isFunctionType(); 485 } 486 487 bool isInstField = ((DS.getStorageClassSpec() == DeclSpec::SCS_unspecified || 488 DS.getStorageClassSpec() == DeclSpec::SCS_mutable) && 489 !isFunc); 490 491 Decl *Member; 492 bool InvalidDecl = false; 493 494 if (isInstField) 495 Member = static_cast<Decl*>(ActOnField(S, Loc, D, BitWidth)); 496 else 497 Member = static_cast<Decl*>(ActOnDeclarator(S, D, LastInGroup)); 498 499 if (!Member) return LastInGroup; 500 501 assert((II || isInstField) && "No identifier for non-field ?"); 502 503 // set/getAccess is not part of Decl's interface to avoid bloating it with C++ 504 // specific methods. Use a wrapper class that can be used with all C++ class 505 // member decls. 506 CXXClassMemberWrapper(Member).setAccess(AS); 507 508 // C++ [dcl.init.aggr]p1: 509 // An aggregate is an array or a class (clause 9) with [...] no 510 // private or protected non-static data members (clause 11). 511 if (isInstField && (AS == AS_private || AS == AS_protected)) 512 cast<CXXRecordDecl>(CurContext)->setAggregate(false); 513 514 if (DS.isVirtualSpecified()) { 515 if (!isFunc || DS.getStorageClassSpec() == DeclSpec::SCS_static) { 516 Diag(DS.getVirtualSpecLoc(), diag::err_virtual_non_function); 517 InvalidDecl = true; 518 } else { 519 CXXRecordDecl *CurClass = cast<CXXRecordDecl>(CurContext); 520 CurClass->setAggregate(false); 521 CurClass->setPolymorphic(true); 522 } 523 } 524 525 if (BitWidth) { 526 // C++ 9.6p2: Only when declaring an unnamed bit-field may the 527 // constant-expression be a value equal to zero. 528 // FIXME: Check this. 529 530 if (D.isFunctionDeclarator()) { 531 // FIXME: Emit diagnostic about only constructors taking base initializers 532 // or something similar, when constructor support is in place. 533 Diag(Loc, diag::err_not_bitfield_type, 534 II->getName(), BitWidth->getSourceRange()); 535 InvalidDecl = true; 536 537 } else if (isInstField) { 538 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 539 if (!cast<FieldDecl>(Member)->getType()->isIntegralType()) { 540 Diag(Loc, diag::err_not_integral_type_bitfield, 541 II->getName(), BitWidth->getSourceRange()); 542 InvalidDecl = true; 543 } 544 545 } else if (isa<FunctionDecl>(Member)) { 546 // A function typedef ("typedef int f(); f a;"). 547 // C++ 9.6p3: A bit-field shall have integral or enumeration type. 548 Diag(Loc, diag::err_not_integral_type_bitfield, 549 II->getName(), BitWidth->getSourceRange()); 550 InvalidDecl = true; 551 552 } else if (isa<TypedefDecl>(Member)) { 553 // "cannot declare 'A' to be a bit-field type" 554 Diag(Loc, diag::err_not_bitfield_type, II->getName(), 555 BitWidth->getSourceRange()); 556 InvalidDecl = true; 557 558 } else { 559 assert(isa<CXXClassVarDecl>(Member) && 560 "Didn't we cover all member kinds?"); 561 // C++ 9.6p3: A bit-field shall not be a static member. 562 // "static member 'A' cannot be a bit-field" 563 Diag(Loc, diag::err_static_not_bitfield, II->getName(), 564 BitWidth->getSourceRange()); 565 InvalidDecl = true; 566 } 567 } 568 569 if (Init) { 570 // C++ 9.2p4: A member-declarator can contain a constant-initializer only 571 // if it declares a static member of const integral or const enumeration 572 // type. 573 if (CXXClassVarDecl *CVD = dyn_cast<CXXClassVarDecl>(Member)) { 574 // ...static member of... 575 CVD->setInit(Init); 576 // ...const integral or const enumeration type. 577 if (Context.getCanonicalType(CVD->getType()).isConstQualified() && 578 CVD->getType()->isIntegralType()) { 579 // constant-initializer 580 if (CheckForConstantInitializer(Init, CVD->getType())) 581 InvalidDecl = true; 582 583 } else { 584 // not const integral. 585 Diag(Loc, diag::err_member_initialization, 586 II->getName(), Init->getSourceRange()); 587 InvalidDecl = true; 588 } 589 590 } else { 591 // not static member. 592 Diag(Loc, diag::err_member_initialization, 593 II->getName(), Init->getSourceRange()); 594 InvalidDecl = true; 595 } 596 } 597 598 if (InvalidDecl) 599 Member->setInvalidDecl(); 600 601 if (isInstField) { 602 FieldCollector->Add(cast<CXXFieldDecl>(Member)); 603 return LastInGroup; 604 } 605 return Member; 606} 607 608/// ActOnMemInitializer - Handle a C++ member initializer. 609Sema::MemInitResult 610Sema::ActOnMemInitializer(DeclTy *ConstructorD, 611 Scope *S, 612 IdentifierInfo *MemberOrBase, 613 SourceLocation IdLoc, 614 SourceLocation LParenLoc, 615 ExprTy **Args, unsigned NumArgs, 616 SourceLocation *CommaLocs, 617 SourceLocation RParenLoc) { 618 CXXConstructorDecl *Constructor 619 = dyn_cast<CXXConstructorDecl>((Decl*)ConstructorD); 620 if (!Constructor) { 621 // The user wrote a constructor initializer on a function that is 622 // not a C++ constructor. Ignore the error for now, because we may 623 // have more member initializers coming; we'll diagnose it just 624 // once in ActOnMemInitializers. 625 return true; 626 } 627 628 CXXRecordDecl *ClassDecl = Constructor->getParent(); 629 630 // C++ [class.base.init]p2: 631 // Names in a mem-initializer-id are looked up in the scope of the 632 // constructor’s class and, if not found in that scope, are looked 633 // up in the scope containing the constructor’s 634 // definition. [Note: if the constructor’s class contains a member 635 // with the same name as a direct or virtual base class of the 636 // class, a mem-initializer-id naming the member or base class and 637 // composed of a single identifier refers to the class member. A 638 // mem-initializer-id for the hidden base class may be specified 639 // using a qualified name. ] 640 // Look for a member, first. 641 CXXFieldDecl *Member = ClassDecl->getMember(MemberOrBase); 642 643 // FIXME: Handle members of an anonymous union. 644 645 if (Member) { 646 // FIXME: Perform direct initialization of the member. 647 return new CXXBaseOrMemberInitializer(Member, (Expr **)Args, NumArgs); 648 } 649 650 // It didn't name a member, so see if it names a class. 651 TypeTy *BaseTy = isTypeName(*MemberOrBase, S, 0/*SS*/); 652 if (!BaseTy) 653 return Diag(IdLoc, diag::err_mem_init_not_member_or_class, 654 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 655 656 QualType BaseType = Context.getTypeDeclType((TypeDecl *)BaseTy); 657 if (!BaseType->isRecordType()) 658 return Diag(IdLoc, diag::err_base_init_does_not_name_class, 659 BaseType.getAsString(), SourceRange(IdLoc, RParenLoc)); 660 661 // C++ [class.base.init]p2: 662 // [...] Unless the mem-initializer-id names a nonstatic data 663 // member of the constructor’s class or a direct or virtual base 664 // of that class, the mem-initializer is ill-formed. A 665 // mem-initializer-list can initialize a base class using any 666 // name that denotes that base class type. 667 668 // First, check for a direct base class. 669 const CXXBaseSpecifier *DirectBaseSpec = 0; 670 for (CXXRecordDecl::base_class_const_iterator Base = ClassDecl->bases_begin(); 671 Base != ClassDecl->bases_end(); ++Base) { 672 if (Context.getCanonicalType(BaseType).getUnqualifiedType() == 673 Context.getCanonicalType(Base->getType()).getUnqualifiedType()) { 674 // We found a direct base of this type. That's what we're 675 // initializing. 676 DirectBaseSpec = &*Base; 677 break; 678 } 679 } 680 681 // Check for a virtual base class. 682 // FIXME: We might be able to short-circuit this if we know in 683 // advance that there are no virtual bases. 684 const CXXBaseSpecifier *VirtualBaseSpec = 0; 685 if (!DirectBaseSpec || !DirectBaseSpec->isVirtual()) { 686 // We haven't found a base yet; search the class hierarchy for a 687 // virtual base class. 688 BasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 689 /*DetectVirtual=*/false); 690 if (IsDerivedFrom(Context.getTypeDeclType(ClassDecl), BaseType, Paths)) { 691 for (BasePaths::paths_iterator Path = Paths.begin(); 692 Path != Paths.end(); ++Path) { 693 if (Path->back().Base->isVirtual()) { 694 VirtualBaseSpec = Path->back().Base; 695 break; 696 } 697 } 698 } 699 } 700 701 // C++ [base.class.init]p2: 702 // If a mem-initializer-id is ambiguous because it designates both 703 // a direct non-virtual base class and an inherited virtual base 704 // class, the mem-initializer is ill-formed. 705 if (DirectBaseSpec && VirtualBaseSpec) 706 return Diag(IdLoc, diag::err_base_init_direct_and_virtual, 707 MemberOrBase->getName(), SourceRange(IdLoc, RParenLoc)); 708 709 return new CXXBaseOrMemberInitializer(BaseType, (Expr **)Args, NumArgs); 710} 711 712 713void Sema::ActOnFinishCXXMemberSpecification(Scope* S, SourceLocation RLoc, 714 DeclTy *TagDecl, 715 SourceLocation LBrac, 716 SourceLocation RBrac) { 717 ActOnFields(S, RLoc, TagDecl, 718 (DeclTy**)FieldCollector->getCurFields(), 719 FieldCollector->getCurNumFields(), LBrac, RBrac, 0); 720} 721 722/// AddImplicitlyDeclaredMembersToClass - Adds any implicitly-declared 723/// special functions, such as the default constructor, copy 724/// constructor, or destructor, to the given C++ class (C++ 725/// [special]p1). This routine can only be executed just before the 726/// definition of the class is complete. 727void Sema::AddImplicitlyDeclaredMembersToClass(CXXRecordDecl *ClassDecl) { 728 if (!ClassDecl->hasUserDeclaredConstructor()) { 729 // C++ [class.ctor]p5: 730 // A default constructor for a class X is a constructor of class X 731 // that can be called without an argument. If there is no 732 // user-declared constructor for class X, a default constructor is 733 // implicitly declared. An implicitly-declared default constructor 734 // is an inline public member of its class. 735 CXXConstructorDecl *DefaultCon = 736 CXXConstructorDecl::Create(Context, ClassDecl, 737 ClassDecl->getLocation(), 738 &Context.Idents.getConstructorId(), 739 Context.getFunctionType(Context.VoidTy, 740 0, 0, false, 0), 741 /*isExplicit=*/false, 742 /*isInline=*/true, 743 /*isImplicitlyDeclared=*/true); 744 DefaultCon->setAccess(AS_public); 745 ClassDecl->addConstructor(Context, DefaultCon); 746 } 747 748 if (!ClassDecl->hasUserDeclaredCopyConstructor()) { 749 // C++ [class.copy]p4: 750 // If the class definition does not explicitly declare a copy 751 // constructor, one is declared implicitly. 752 753 // C++ [class.copy]p5: 754 // The implicitly-declared copy constructor for a class X will 755 // have the form 756 // 757 // X::X(const X&) 758 // 759 // if 760 bool HasConstCopyConstructor = true; 761 762 // -- each direct or virtual base class B of X has a copy 763 // constructor whose first parameter is of type const B& or 764 // const volatile B&, and 765 for (CXXRecordDecl::base_class_iterator Base = ClassDecl->bases_begin(); 766 HasConstCopyConstructor && Base != ClassDecl->bases_end(); ++Base) { 767 const CXXRecordDecl *BaseClassDecl 768 = cast<CXXRecordDecl>(Base->getType()->getAsRecordType()->getDecl()); 769 HasConstCopyConstructor 770 = BaseClassDecl->hasConstCopyConstructor(Context); 771 } 772 773 // -- for all the nonstatic data members of X that are of a 774 // class type M (or array thereof), each such class type 775 // has a copy constructor whose first parameter is of type 776 // const M& or const volatile M&. 777 for (CXXRecordDecl::field_iterator Field = ClassDecl->field_begin(); 778 HasConstCopyConstructor && Field != ClassDecl->field_end(); ++Field) { 779 QualType FieldType = (*Field)->getType(); 780 if (const ArrayType *Array = Context.getAsArrayType(FieldType)) 781 FieldType = Array->getElementType(); 782 if (const RecordType *FieldClassType = FieldType->getAsRecordType()) { 783 const CXXRecordDecl *FieldClassDecl 784 = cast<CXXRecordDecl>(FieldClassType->getDecl()); 785 HasConstCopyConstructor 786 = FieldClassDecl->hasConstCopyConstructor(Context); 787 } 788 } 789 790 // Otherwise, the implicitly declared copy constructor will have 791 // the form 792 // 793 // X::X(X&) 794 QualType ArgType = Context.getTypeDeclType(ClassDecl); 795 if (HasConstCopyConstructor) 796 ArgType = ArgType.withConst(); 797 ArgType = Context.getReferenceType(ArgType); 798 799 // An implicitly-declared copy constructor is an inline public 800 // member of its class. 801 CXXConstructorDecl *CopyConstructor 802 = CXXConstructorDecl::Create(Context, ClassDecl, 803 ClassDecl->getLocation(), 804 &Context.Idents.getConstructorId(), 805 Context.getFunctionType(Context.VoidTy, 806 &ArgType, 1, 807 false, 0), 808 /*isExplicit=*/false, 809 /*isInline=*/true, 810 /*isImplicitlyDeclared=*/true); 811 CopyConstructor->setAccess(AS_public); 812 813 // Add the parameter to the constructor. 814 ParmVarDecl *FromParam = ParmVarDecl::Create(Context, CopyConstructor, 815 ClassDecl->getLocation(), 816 /*IdentifierInfo=*/0, 817 ArgType, VarDecl::None, 0, 0); 818 CopyConstructor->setParams(&FromParam, 1); 819 820 ClassDecl->addConstructor(Context, CopyConstructor); 821 } 822 823 if (!ClassDecl->getDestructor()) { 824 // C++ [class.dtor]p2: 825 // If a class has no user-declared destructor, a destructor is 826 // declared implicitly. An implicitly-declared destructor is an 827 // inline public member of its class. 828 CXXDestructorDecl *Destructor 829 = CXXDestructorDecl::Create(Context, ClassDecl, 830 ClassDecl->getLocation(), 831 &Context.Idents.getConstructorId(), 832 Context.getFunctionType(Context.VoidTy, 833 0, 0, false, 0), 834 /*isInline=*/true, 835 /*isImplicitlyDeclared=*/true); 836 Destructor->setAccess(AS_public); 837 ClassDecl->setDestructor(Destructor); 838 } 839 840 // FIXME: Implicit copy assignment operator 841} 842 843void Sema::ActOnFinishCXXClassDef(DeclTy *D) { 844 CXXRecordDecl *Rec = cast<CXXRecordDecl>(static_cast<Decl *>(D)); 845 FieldCollector->FinishClass(); 846 AddImplicitlyDeclaredMembersToClass(Rec); 847 PopDeclContext(); 848 849 // Everything, including inline method definitions, have been parsed. 850 // Let the consumer know of the new TagDecl definition. 851 Consumer.HandleTagDeclDefinition(Rec); 852} 853 854/// CheckConstructorDeclarator - Called by ActOnDeclarator to check 855/// the well-formednes of the constructor declarator @p D with type @p 856/// R. If there are any errors in the declarator, this routine will 857/// emit diagnostics and return true. Otherwise, it will return 858/// false. Either way, the type @p R will be updated to reflect a 859/// well-formed type for the constructor. 860bool Sema::CheckConstructorDeclarator(Declarator &D, QualType &R, 861 FunctionDecl::StorageClass& SC) { 862 bool isVirtual = D.getDeclSpec().isVirtualSpecified(); 863 bool isInvalid = false; 864 865 // C++ [class.ctor]p3: 866 // A constructor shall not be virtual (10.3) or static (9.4). A 867 // constructor can be invoked for a const, volatile or const 868 // volatile object. A constructor shall not be declared const, 869 // volatile, or const volatile (9.3.2). 870 if (isVirtual) { 871 Diag(D.getIdentifierLoc(), 872 diag::err_constructor_cannot_be, 873 "virtual", 874 SourceRange(D.getDeclSpec().getVirtualSpecLoc()), 875 SourceRange(D.getIdentifierLoc())); 876 isInvalid = true; 877 } 878 if (SC == FunctionDecl::Static) { 879 Diag(D.getIdentifierLoc(), 880 diag::err_constructor_cannot_be, 881 "static", 882 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 883 SourceRange(D.getIdentifierLoc())); 884 isInvalid = true; 885 SC = FunctionDecl::None; 886 } 887 if (D.getDeclSpec().hasTypeSpecifier()) { 888 // Constructors don't have return types, but the parser will 889 // happily parse something like: 890 // 891 // class X { 892 // float X(float); 893 // }; 894 // 895 // The return type will be eliminated later. 896 Diag(D.getIdentifierLoc(), 897 diag::err_constructor_return_type, 898 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 899 SourceRange(D.getIdentifierLoc())); 900 } 901 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 902 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 903 if (FTI.TypeQuals & QualType::Const) 904 Diag(D.getIdentifierLoc(), 905 diag::err_invalid_qualified_constructor, 906 "const", 907 SourceRange(D.getIdentifierLoc())); 908 if (FTI.TypeQuals & QualType::Volatile) 909 Diag(D.getIdentifierLoc(), 910 diag::err_invalid_qualified_constructor, 911 "volatile", 912 SourceRange(D.getIdentifierLoc())); 913 if (FTI.TypeQuals & QualType::Restrict) 914 Diag(D.getIdentifierLoc(), 915 diag::err_invalid_qualified_constructor, 916 "restrict", 917 SourceRange(D.getIdentifierLoc())); 918 } 919 920 // Rebuild the function type "R" without any type qualifiers (in 921 // case any of the errors above fired) and with "void" as the 922 // return type, since constructors don't have return types. We 923 // *always* have to do this, because GetTypeForDeclarator will 924 // put in a result type of "int" when none was specified. 925 const FunctionTypeProto *Proto = R->getAsFunctionTypeProto(); 926 R = Context.getFunctionType(Context.VoidTy, Proto->arg_type_begin(), 927 Proto->getNumArgs(), 928 Proto->isVariadic(), 929 0); 930 931 return isInvalid; 932} 933 934/// CheckDestructorDeclarator - Called by ActOnDeclarator to check 935/// the well-formednes of the destructor declarator @p D with type @p 936/// R. If there are any errors in the declarator, this routine will 937/// emit diagnostics and return true. Otherwise, it will return 938/// false. Either way, the type @p R will be updated to reflect a 939/// well-formed type for the destructor. 940bool Sema::CheckDestructorDeclarator(Declarator &D, QualType &R, 941 FunctionDecl::StorageClass& SC) { 942 bool isInvalid = false; 943 944 // C++ [class.dtor]p1: 945 // [...] A typedef-name that names a class is a class-name 946 // (7.1.3); however, a typedef-name that names a class shall not 947 // be used as the identifier in the declarator for a destructor 948 // declaration. 949 TypeDecl *DeclaratorTypeD = (TypeDecl *)D.getDeclaratorIdType(); 950 if (const TypedefDecl *TypedefD = dyn_cast<TypedefDecl>(DeclaratorTypeD)) { 951 Diag(D.getIdentifierLoc(), 952 diag::err_destructor_typedef_name, 953 TypedefD->getName()); 954 isInvalid = true; 955 } 956 957 // C++ [class.dtor]p2: 958 // A destructor is used to destroy objects of its class type. A 959 // destructor takes no parameters, and no return type can be 960 // specified for it (not even void). The address of a destructor 961 // shall not be taken. A destructor shall not be static. A 962 // destructor can be invoked for a const, volatile or const 963 // volatile object. A destructor shall not be declared const, 964 // volatile or const volatile (9.3.2). 965 if (SC == FunctionDecl::Static) { 966 Diag(D.getIdentifierLoc(), 967 diag::err_destructor_cannot_be, 968 "static", 969 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 970 SourceRange(D.getIdentifierLoc())); 971 isInvalid = true; 972 SC = FunctionDecl::None; 973 } 974 if (D.getDeclSpec().hasTypeSpecifier()) { 975 // Destructors don't have return types, but the parser will 976 // happily parse something like: 977 // 978 // class X { 979 // float ~X(); 980 // }; 981 // 982 // The return type will be eliminated later. 983 Diag(D.getIdentifierLoc(), 984 diag::err_destructor_return_type, 985 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 986 SourceRange(D.getIdentifierLoc())); 987 } 988 if (R->getAsFunctionTypeProto()->getTypeQuals() != 0) { 989 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 990 if (FTI.TypeQuals & QualType::Const) 991 Diag(D.getIdentifierLoc(), 992 diag::err_invalid_qualified_destructor, 993 "const", 994 SourceRange(D.getIdentifierLoc())); 995 if (FTI.TypeQuals & QualType::Volatile) 996 Diag(D.getIdentifierLoc(), 997 diag::err_invalid_qualified_destructor, 998 "volatile", 999 SourceRange(D.getIdentifierLoc())); 1000 if (FTI.TypeQuals & QualType::Restrict) 1001 Diag(D.getIdentifierLoc(), 1002 diag::err_invalid_qualified_destructor, 1003 "restrict", 1004 SourceRange(D.getIdentifierLoc())); 1005 } 1006 1007 // Make sure we don't have any parameters. 1008 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 1009 Diag(D.getIdentifierLoc(), diag::err_destructor_with_params); 1010 1011 // Delete the parameters. 1012 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1013 if (FTI.NumArgs) { 1014 delete [] FTI.ArgInfo; 1015 FTI.NumArgs = 0; 1016 FTI.ArgInfo = 0; 1017 } 1018 } 1019 1020 // Make sure the destructor isn't variadic. 1021 if (R->getAsFunctionTypeProto()->isVariadic()) 1022 Diag(D.getIdentifierLoc(), diag::err_destructor_variadic); 1023 1024 // Rebuild the function type "R" without any type qualifiers or 1025 // parameters (in case any of the errors above fired) and with 1026 // "void" as the return type, since destructors don't have return 1027 // types. We *always* have to do this, because GetTypeForDeclarator 1028 // will put in a result type of "int" when none was specified. 1029 R = Context.getFunctionType(Context.VoidTy, 0, 0, false, 0); 1030 1031 return isInvalid; 1032} 1033 1034/// CheckConversionDeclarator - Called by ActOnDeclarator to check the 1035/// well-formednes of the conversion function declarator @p D with 1036/// type @p R. If there are any errors in the declarator, this routine 1037/// will emit diagnostics and return true. Otherwise, it will return 1038/// false. Either way, the type @p R will be updated to reflect a 1039/// well-formed type for the conversion operator. 1040bool Sema::CheckConversionDeclarator(Declarator &D, QualType &R, 1041 FunctionDecl::StorageClass& SC) { 1042 bool isInvalid = false; 1043 1044 // C++ [class.conv.fct]p1: 1045 // Neither parameter types nor return type can be specified. The 1046 // type of a conversion function (8.3.5) is “function taking no 1047 // parameter returning conversion-type-id.” 1048 if (SC == FunctionDecl::Static) { 1049 Diag(D.getIdentifierLoc(), 1050 diag::err_conv_function_not_member, 1051 "static", 1052 SourceRange(D.getDeclSpec().getStorageClassSpecLoc()), 1053 SourceRange(D.getIdentifierLoc())); 1054 isInvalid = true; 1055 SC = FunctionDecl::None; 1056 } 1057 if (D.getDeclSpec().hasTypeSpecifier()) { 1058 // Conversion functions don't have return types, but the parser will 1059 // happily parse something like: 1060 // 1061 // class X { 1062 // float operator bool(); 1063 // }; 1064 // 1065 // The return type will be changed later anyway. 1066 Diag(D.getIdentifierLoc(), 1067 diag::err_conv_function_return_type, 1068 SourceRange(D.getDeclSpec().getTypeSpecTypeLoc()), 1069 SourceRange(D.getIdentifierLoc())); 1070 } 1071 1072 // Make sure we don't have any parameters. 1073 if (R->getAsFunctionTypeProto()->getNumArgs() > 0) { 1074 Diag(D.getIdentifierLoc(), diag::err_conv_function_with_params); 1075 1076 // Delete the parameters. 1077 DeclaratorChunk::FunctionTypeInfo &FTI = D.getTypeObject(0).Fun; 1078 if (FTI.NumArgs) { 1079 delete [] FTI.ArgInfo; 1080 FTI.NumArgs = 0; 1081 FTI.ArgInfo = 0; 1082 } 1083 } 1084 1085 // Make sure the conversion function isn't variadic. 1086 if (R->getAsFunctionTypeProto()->isVariadic()) 1087 Diag(D.getIdentifierLoc(), diag::err_conv_function_variadic); 1088 1089 // C++ [class.conv.fct]p4: 1090 // The conversion-type-id shall not represent a function type nor 1091 // an array type. 1092 QualType ConvType = QualType::getFromOpaquePtr(D.getDeclaratorIdType()); 1093 if (ConvType->isArrayType()) { 1094 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_array); 1095 ConvType = Context.getPointerType(ConvType); 1096 } else if (ConvType->isFunctionType()) { 1097 Diag(D.getIdentifierLoc(), diag::err_conv_function_to_function); 1098 ConvType = Context.getPointerType(ConvType); 1099 } 1100 1101 // Rebuild the function type "R" without any parameters (in case any 1102 // of the errors above fired) and with the conversion type as the 1103 // return type. 1104 R = Context.getFunctionType(ConvType, 0, 0, false, 1105 R->getAsFunctionTypeProto()->getTypeQuals()); 1106 1107 return isInvalid; 1108} 1109 1110/// ActOnConstructorDeclarator - Called by ActOnDeclarator to complete 1111/// the declaration of the given C++ constructor ConDecl that was 1112/// built from declarator D. This routine is responsible for checking 1113/// that the newly-created constructor declaration is well-formed and 1114/// for recording it in the C++ class. Example: 1115/// 1116/// @code 1117/// class X { 1118/// X(); // X::X() will be the ConDecl. 1119/// }; 1120/// @endcode 1121Sema::DeclTy *Sema::ActOnConstructorDeclarator(CXXConstructorDecl *ConDecl) { 1122 assert(ConDecl && "Expected to receive a constructor declaration"); 1123 1124 // Check default arguments on the constructor 1125 CheckCXXDefaultArguments(ConDecl); 1126 1127 CXXRecordDecl *ClassDecl = dyn_cast_or_null<CXXRecordDecl>(CurContext); 1128 if (!ClassDecl) { 1129 ConDecl->setInvalidDecl(); 1130 return ConDecl; 1131 } 1132 1133 // Make sure this constructor is an overload of the existing 1134 // constructors. 1135 OverloadedFunctionDecl::function_iterator MatchedDecl; 1136 if (!IsOverload(ConDecl, ClassDecl->getConstructors(), MatchedDecl)) { 1137 Diag(ConDecl->getLocation(), 1138 diag::err_constructor_redeclared, 1139 SourceRange(ConDecl->getLocation())); 1140 Diag((*MatchedDecl)->getLocation(), 1141 diag::err_previous_declaration, 1142 SourceRange((*MatchedDecl)->getLocation())); 1143 ConDecl->setInvalidDecl(); 1144 return ConDecl; 1145 } 1146 1147 1148 // C++ [class.copy]p3: 1149 // A declaration of a constructor for a class X is ill-formed if 1150 // its first parameter is of type (optionally cv-qualified) X and 1151 // either there are no other parameters or else all other 1152 // parameters have default arguments. 1153 if ((ConDecl->getNumParams() == 1) || 1154 (ConDecl->getNumParams() > 1 && 1155 ConDecl->getParamDecl(1)->getDefaultArg() != 0)) { 1156 QualType ParamType = ConDecl->getParamDecl(0)->getType(); 1157 QualType ClassTy = Context.getTagDeclType( 1158 const_cast<CXXRecordDecl*>(ConDecl->getParent())); 1159 if (Context.getCanonicalType(ParamType).getUnqualifiedType() == ClassTy) { 1160 Diag(ConDecl->getLocation(), 1161 diag::err_constructor_byvalue_arg, 1162 SourceRange(ConDecl->getParamDecl(0)->getLocation())); 1163 ConDecl->setInvalidDecl(); 1164 return ConDecl; 1165 } 1166 } 1167 1168 // Add this constructor to the set of constructors of the current 1169 // class. 1170 ClassDecl->addConstructor(Context, ConDecl); 1171 return (DeclTy *)ConDecl; 1172} 1173 1174/// ActOnDestructorDeclarator - Called by ActOnDeclarator to complete 1175/// the declaration of the given C++ @p Destructor. This routine is 1176/// responsible for recording the destructor in the C++ class, if 1177/// possible. 1178Sema::DeclTy *Sema::ActOnDestructorDeclarator(CXXDestructorDecl *Destructor) { 1179 assert(Destructor && "Expected to receive a destructor declaration"); 1180 1181 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1182 1183 // Make sure we aren't redeclaring the destructor. 1184 if (CXXDestructorDecl *PrevDestructor = ClassDecl->getDestructor()) { 1185 Diag(Destructor->getLocation(), diag::err_destructor_redeclared); 1186 Diag(PrevDestructor->getLocation(), 1187 PrevDestructor->isThisDeclarationADefinition()? 1188 diag::err_previous_definition 1189 : diag::err_previous_declaration); 1190 Destructor->setInvalidDecl(); 1191 return Destructor; 1192 } 1193 1194 ClassDecl->setDestructor(Destructor); 1195 return (DeclTy *)Destructor; 1196} 1197 1198/// ActOnConversionDeclarator - Called by ActOnDeclarator to complete 1199/// the declaration of the given C++ conversion function. This routine 1200/// is responsible for recording the conversion function in the C++ 1201/// class, if possible. 1202Sema::DeclTy *Sema::ActOnConversionDeclarator(CXXConversionDecl *Conversion) { 1203 assert(Conversion && "Expected to receive a conversion function declaration"); 1204 1205 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(CurContext); 1206 1207 // Make sure we aren't redeclaring the conversion function. 1208 QualType ConvType = Context.getCanonicalType(Conversion->getConversionType()); 1209 OverloadedFunctionDecl *Conversions = ClassDecl->getConversionFunctions(); 1210 for (OverloadedFunctionDecl::function_iterator Func 1211 = Conversions->function_begin(); 1212 Func != Conversions->function_end(); ++Func) { 1213 CXXConversionDecl *OtherConv = cast<CXXConversionDecl>(*Func); 1214 if (ConvType == Context.getCanonicalType(OtherConv->getConversionType())) { 1215 Diag(Conversion->getLocation(), diag::err_conv_function_redeclared); 1216 Diag(OtherConv->getLocation(), 1217 OtherConv->isThisDeclarationADefinition()? 1218 diag::err_previous_definition 1219 : diag::err_previous_declaration); 1220 Conversion->setInvalidDecl(); 1221 return (DeclTy *)Conversion; 1222 } 1223 } 1224 1225 // C++ [class.conv.fct]p1: 1226 // [...] A conversion function is never used to convert a 1227 // (possibly cv-qualified) object to the (possibly cv-qualified) 1228 // same object type (or a reference to it), to a (possibly 1229 // cv-qualified) base class of that type (or a reference to it), 1230 // or to (possibly cv-qualified) void. 1231 // FIXME: Suppress this warning if the conversion function ends up 1232 // being a virtual function that overrides a virtual function in a 1233 // base class. 1234 QualType ClassType 1235 = Context.getCanonicalType(Context.getTypeDeclType(ClassDecl)); 1236 if (const ReferenceType *ConvTypeRef = ConvType->getAsReferenceType()) 1237 ConvType = ConvTypeRef->getPointeeType(); 1238 if (ConvType->isRecordType()) { 1239 ConvType = Context.getCanonicalType(ConvType).getUnqualifiedType(); 1240 if (ConvType == ClassType) 1241 Diag(Conversion->getLocation(), diag::warn_conv_to_self_not_used, 1242 ClassType.getAsString()); 1243 else if (IsDerivedFrom(ClassType, ConvType)) 1244 Diag(Conversion->getLocation(), diag::warn_conv_to_base_not_used, 1245 ClassType.getAsString(), 1246 ConvType.getAsString()); 1247 } else if (ConvType->isVoidType()) { 1248 Diag(Conversion->getLocation(), diag::warn_conv_to_void_not_used, 1249 ClassType.getAsString(), ConvType.getAsString()); 1250 } 1251 1252 ClassDecl->addConversionFunction(Context, Conversion); 1253 1254 return (DeclTy *)Conversion; 1255} 1256 1257//===----------------------------------------------------------------------===// 1258// Namespace Handling 1259//===----------------------------------------------------------------------===// 1260 1261/// ActOnStartNamespaceDef - This is called at the start of a namespace 1262/// definition. 1263Sema::DeclTy *Sema::ActOnStartNamespaceDef(Scope *NamespcScope, 1264 SourceLocation IdentLoc, 1265 IdentifierInfo *II, 1266 SourceLocation LBrace) { 1267 NamespaceDecl *Namespc = 1268 NamespaceDecl::Create(Context, CurContext, IdentLoc, II); 1269 Namespc->setLBracLoc(LBrace); 1270 1271 Scope *DeclRegionScope = NamespcScope->getParent(); 1272 1273 if (II) { 1274 // C++ [namespace.def]p2: 1275 // The identifier in an original-namespace-definition shall not have been 1276 // previously defined in the declarative region in which the 1277 // original-namespace-definition appears. The identifier in an 1278 // original-namespace-definition is the name of the namespace. Subsequently 1279 // in that declarative region, it is treated as an original-namespace-name. 1280 1281 Decl *PrevDecl = 1282 LookupDecl(II, Decl::IDNS_Tag | Decl::IDNS_Ordinary, DeclRegionScope, 0, 1283 /*enableLazyBuiltinCreation=*/false); 1284 1285 if (PrevDecl && isDeclInScope(PrevDecl, CurContext, DeclRegionScope)) { 1286 if (NamespaceDecl *OrigNS = dyn_cast<NamespaceDecl>(PrevDecl)) { 1287 // This is an extended namespace definition. 1288 // Attach this namespace decl to the chain of extended namespace 1289 // definitions. 1290 NamespaceDecl *NextNS = OrigNS; 1291 while (NextNS->getNextNamespace()) 1292 NextNS = NextNS->getNextNamespace(); 1293 1294 NextNS->setNextNamespace(Namespc); 1295 Namespc->setOriginalNamespace(OrigNS); 1296 1297 // We won't add this decl to the current scope. We want the namespace 1298 // name to return the original namespace decl during a name lookup. 1299 } else { 1300 // This is an invalid name redefinition. 1301 Diag(Namespc->getLocation(), diag::err_redefinition_different_kind, 1302 Namespc->getName()); 1303 Diag(PrevDecl->getLocation(), diag::err_previous_definition); 1304 Namespc->setInvalidDecl(); 1305 // Continue on to push Namespc as current DeclContext and return it. 1306 } 1307 } else { 1308 // This namespace name is declared for the first time. 1309 PushOnScopeChains(Namespc, DeclRegionScope); 1310 } 1311 } 1312 else { 1313 // FIXME: Handle anonymous namespaces 1314 } 1315 1316 // Although we could have an invalid decl (i.e. the namespace name is a 1317 // redefinition), push it as current DeclContext and try to continue parsing. 1318 PushDeclContext(Namespc->getOriginalNamespace()); 1319 return Namespc; 1320} 1321 1322/// ActOnFinishNamespaceDef - This callback is called after a namespace is 1323/// exited. Decl is the DeclTy returned by ActOnStartNamespaceDef. 1324void Sema::ActOnFinishNamespaceDef(DeclTy *D, SourceLocation RBrace) { 1325 Decl *Dcl = static_cast<Decl *>(D); 1326 NamespaceDecl *Namespc = dyn_cast_or_null<NamespaceDecl>(Dcl); 1327 assert(Namespc && "Invalid parameter, expected NamespaceDecl"); 1328 Namespc->setRBracLoc(RBrace); 1329 PopDeclContext(); 1330} 1331 1332 1333/// AddCXXDirectInitializerToDecl - This action is called immediately after 1334/// ActOnDeclarator, when a C++ direct initializer is present. 1335/// e.g: "int x(1);" 1336void Sema::AddCXXDirectInitializerToDecl(DeclTy *Dcl, SourceLocation LParenLoc, 1337 ExprTy **ExprTys, unsigned NumExprs, 1338 SourceLocation *CommaLocs, 1339 SourceLocation RParenLoc) { 1340 assert(NumExprs != 0 && ExprTys && "missing expressions"); 1341 Decl *RealDecl = static_cast<Decl *>(Dcl); 1342 1343 // If there is no declaration, there was an error parsing it. Just ignore 1344 // the initializer. 1345 if (RealDecl == 0) { 1346 for (unsigned i = 0; i != NumExprs; ++i) 1347 delete static_cast<Expr *>(ExprTys[i]); 1348 return; 1349 } 1350 1351 VarDecl *VDecl = dyn_cast<VarDecl>(RealDecl); 1352 if (!VDecl) { 1353 Diag(RealDecl->getLocation(), diag::err_illegal_initializer); 1354 RealDecl->setInvalidDecl(); 1355 return; 1356 } 1357 1358 // We will treat direct-initialization as a copy-initialization: 1359 // int x(1); -as-> int x = 1; 1360 // ClassType x(a,b,c); -as-> ClassType x = ClassType(a,b,c); 1361 // 1362 // Clients that want to distinguish between the two forms, can check for 1363 // direct initializer using VarDecl::hasCXXDirectInitializer(). 1364 // A major benefit is that clients that don't particularly care about which 1365 // exactly form was it (like the CodeGen) can handle both cases without 1366 // special case code. 1367 1368 // C++ 8.5p11: 1369 // The form of initialization (using parentheses or '=') is generally 1370 // insignificant, but does matter when the entity being initialized has a 1371 // class type. 1372 QualType DeclInitType = VDecl->getType(); 1373 if (const ArrayType *Array = Context.getAsArrayType(DeclInitType)) 1374 DeclInitType = Array->getElementType(); 1375 1376 if (VDecl->getType()->isRecordType()) { 1377 CXXConstructorDecl *Constructor 1378 = PerformInitializationByConstructor(DeclInitType, 1379 (Expr **)ExprTys, NumExprs, 1380 VDecl->getLocation(), 1381 SourceRange(VDecl->getLocation(), 1382 RParenLoc), 1383 VDecl->getName(), 1384 IK_Direct); 1385 if (!Constructor) { 1386 RealDecl->setInvalidDecl(); 1387 } 1388 1389 // Let clients know that initialization was done with a direct 1390 // initializer. 1391 VDecl->setCXXDirectInitializer(true); 1392 1393 // FIXME: Add ExprTys and Constructor to the RealDecl as part of 1394 // the initializer. 1395 return; 1396 } 1397 1398 if (NumExprs > 1) { 1399 Diag(CommaLocs[0], diag::err_builtin_direct_init_more_than_one_arg, 1400 SourceRange(VDecl->getLocation(), RParenLoc)); 1401 RealDecl->setInvalidDecl(); 1402 return; 1403 } 1404 1405 // Let clients know that initialization was done with a direct initializer. 1406 VDecl->setCXXDirectInitializer(true); 1407 1408 assert(NumExprs == 1 && "Expected 1 expression"); 1409 // Set the init expression, handles conversions. 1410 AddInitializerToDecl(Dcl, ExprTys[0]); 1411} 1412 1413/// PerformInitializationByConstructor - Perform initialization by 1414/// constructor (C++ [dcl.init]p14), which may occur as part of 1415/// direct-initialization or copy-initialization. We are initializing 1416/// an object of type @p ClassType with the given arguments @p 1417/// Args. @p Loc is the location in the source code where the 1418/// initializer occurs (e.g., a declaration, member initializer, 1419/// functional cast, etc.) while @p Range covers the whole 1420/// initialization. @p InitEntity is the entity being initialized, 1421/// which may by the name of a declaration or a type. @p Kind is the 1422/// kind of initialization we're performing, which affects whether 1423/// explicit constructors will be considered. When successful, returns 1424/// the constructor that will be used to perform the initialization; 1425/// when the initialization fails, emits a diagnostic and returns 1426/// null. 1427CXXConstructorDecl * 1428Sema::PerformInitializationByConstructor(QualType ClassType, 1429 Expr **Args, unsigned NumArgs, 1430 SourceLocation Loc, SourceRange Range, 1431 std::string InitEntity, 1432 InitializationKind Kind) { 1433 const RecordType *ClassRec = ClassType->getAsRecordType(); 1434 assert(ClassRec && "Can only initialize a class type here"); 1435 1436 // C++ [dcl.init]p14: 1437 // 1438 // If the initialization is direct-initialization, or if it is 1439 // copy-initialization where the cv-unqualified version of the 1440 // source type is the same class as, or a derived class of, the 1441 // class of the destination, constructors are considered. The 1442 // applicable constructors are enumerated (13.3.1.3), and the 1443 // best one is chosen through overload resolution (13.3). The 1444 // constructor so selected is called to initialize the object, 1445 // with the initializer expression(s) as its argument(s). If no 1446 // constructor applies, or the overload resolution is ambiguous, 1447 // the initialization is ill-formed. 1448 const CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(ClassRec->getDecl()); 1449 OverloadCandidateSet CandidateSet; 1450 1451 // Add constructors to the overload set. 1452 OverloadedFunctionDecl *Constructors 1453 = const_cast<OverloadedFunctionDecl *>(ClassDecl->getConstructors()); 1454 for (OverloadedFunctionDecl::function_iterator Con 1455 = Constructors->function_begin(); 1456 Con != Constructors->function_end(); ++Con) { 1457 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(*Con); 1458 if ((Kind == IK_Direct) || 1459 (Kind == IK_Copy && Constructor->isConvertingConstructor()) || 1460 (Kind == IK_Default && Constructor->isDefaultConstructor())) 1461 AddOverloadCandidate(Constructor, Args, NumArgs, CandidateSet); 1462 } 1463 1464 OverloadCandidateSet::iterator Best; 1465 switch (BestViableFunction(CandidateSet, Best)) { 1466 case OR_Success: 1467 // We found a constructor. Return it. 1468 return cast<CXXConstructorDecl>(Best->Function); 1469 1470 case OR_No_Viable_Function: 1471 if (CandidateSet.empty()) 1472 Diag(Loc, diag::err_ovl_no_viable_function_in_init, 1473 InitEntity, Range); 1474 else { 1475 Diag(Loc, diag::err_ovl_no_viable_function_in_init_with_cands, 1476 InitEntity, Range); 1477 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/false); 1478 } 1479 return 0; 1480 1481 case OR_Ambiguous: 1482 Diag(Loc, diag::err_ovl_ambiguous_init, 1483 InitEntity, Range); 1484 PrintOverloadCandidates(CandidateSet, /*OnlyViable=*/true); 1485 return 0; 1486 } 1487 1488 return 0; 1489} 1490 1491/// CompareReferenceRelationship - Compare the two types T1 and T2 to 1492/// determine whether they are reference-related, 1493/// reference-compatible, reference-compatible with added 1494/// qualification, or incompatible, for use in C++ initialization by 1495/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 1496/// type, and the first type (T1) is the pointee type of the reference 1497/// type being initialized. 1498Sema::ReferenceCompareResult 1499Sema::CompareReferenceRelationship(QualType T1, QualType T2, 1500 bool& DerivedToBase) { 1501 assert(!T1->isReferenceType() && "T1 must be the pointee type of the reference type"); 1502 assert(!T2->isReferenceType() && "T2 cannot be a reference type"); 1503 1504 T1 = Context.getCanonicalType(T1); 1505 T2 = Context.getCanonicalType(T2); 1506 QualType UnqualT1 = T1.getUnqualifiedType(); 1507 QualType UnqualT2 = T2.getUnqualifiedType(); 1508 1509 // C++ [dcl.init.ref]p4: 1510 // Given types “cv1 T1” and “cv2 T2,” “cv1 T1” is 1511 // reference-related to “cv2 T2” if T1 is the same type as T2, or 1512 // T1 is a base class of T2. 1513 if (UnqualT1 == UnqualT2) 1514 DerivedToBase = false; 1515 else if (IsDerivedFrom(UnqualT2, UnqualT1)) 1516 DerivedToBase = true; 1517 else 1518 return Ref_Incompatible; 1519 1520 // At this point, we know that T1 and T2 are reference-related (at 1521 // least). 1522 1523 // C++ [dcl.init.ref]p4: 1524 // "cv1 T1” is reference-compatible with “cv2 T2” if T1 is 1525 // reference-related to T2 and cv1 is the same cv-qualification 1526 // as, or greater cv-qualification than, cv2. For purposes of 1527 // overload resolution, cases for which cv1 is greater 1528 // cv-qualification than cv2 are identified as 1529 // reference-compatible with added qualification (see 13.3.3.2). 1530 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 1531 return Ref_Compatible; 1532 else if (T1.isMoreQualifiedThan(T2)) 1533 return Ref_Compatible_With_Added_Qualification; 1534 else 1535 return Ref_Related; 1536} 1537 1538/// CheckReferenceInit - Check the initialization of a reference 1539/// variable with the given initializer (C++ [dcl.init.ref]). Init is 1540/// the initializer (either a simple initializer or an initializer 1541/// list), and DeclType is the type of the declaration. When ICS is 1542/// non-null, this routine will compute the implicit conversion 1543/// sequence according to C++ [over.ics.ref] and will not produce any 1544/// diagnostics; when ICS is null, it will emit diagnostics when any 1545/// errors are found. Either way, a return value of true indicates 1546/// that there was a failure, a return value of false indicates that 1547/// the reference initialization succeeded. 1548/// 1549/// When @p SuppressUserConversions, user-defined conversions are 1550/// suppressed. 1551bool 1552Sema::CheckReferenceInit(Expr *&Init, QualType &DeclType, 1553 ImplicitConversionSequence *ICS, 1554 bool SuppressUserConversions) { 1555 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 1556 1557 QualType T1 = DeclType->getAsReferenceType()->getPointeeType(); 1558 QualType T2 = Init->getType(); 1559 1560 // If the initializer is the address of an overloaded function, try 1561 // to resolve the overloaded function. If all goes well, T2 is the 1562 // type of the resulting function. 1563 if (T2->isOverloadType()) { 1564 FunctionDecl *Fn = ResolveAddressOfOverloadedFunction(Init, DeclType, 1565 ICS != 0); 1566 if (Fn) { 1567 // Since we're performing this reference-initialization for 1568 // real, update the initializer with the resulting function. 1569 if (!ICS) 1570 FixOverloadedFunctionReference(Init, Fn); 1571 1572 T2 = Fn->getType(); 1573 } 1574 } 1575 1576 // Compute some basic properties of the types and the initializer. 1577 bool DerivedToBase = false; 1578 Expr::isLvalueResult InitLvalue = Init->isLvalue(Context); 1579 ReferenceCompareResult RefRelationship 1580 = CompareReferenceRelationship(T1, T2, DerivedToBase); 1581 1582 // Most paths end in a failed conversion. 1583 if (ICS) 1584 ICS->ConversionKind = ImplicitConversionSequence::BadConversion; 1585 1586 // C++ [dcl.init.ref]p5: 1587 // A reference to type “cv1 T1” is initialized by an expression 1588 // of type “cv2 T2” as follows: 1589 1590 // -- If the initializer expression 1591 1592 bool BindsDirectly = false; 1593 // -- is an lvalue (but is not a bit-field), and “cv1 T1” is 1594 // reference-compatible with “cv2 T2,” or 1595 // 1596 // Note that the bit-field check is skipped if we are just computing 1597 // the implicit conversion sequence (C++ [over.best.ics]p2). 1598 if (InitLvalue == Expr::LV_Valid && (ICS || !Init->isBitField()) && 1599 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1600 BindsDirectly = true; 1601 1602 if (ICS) { 1603 // C++ [over.ics.ref]p1: 1604 // When a parameter of reference type binds directly (8.5.3) 1605 // to an argument expression, the implicit conversion sequence 1606 // is the identity conversion, unless the argument expression 1607 // has a type that is a derived class of the parameter type, 1608 // in which case the implicit conversion sequence is a 1609 // derived-to-base Conversion (13.3.3.1). 1610 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1611 ICS->Standard.First = ICK_Identity; 1612 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1613 ICS->Standard.Third = ICK_Identity; 1614 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1615 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1616 ICS->Standard.ReferenceBinding = true; 1617 ICS->Standard.DirectBinding = true; 1618 1619 // Nothing more to do: the inaccessibility/ambiguity check for 1620 // derived-to-base conversions is suppressed when we're 1621 // computing the implicit conversion sequence (C++ 1622 // [over.best.ics]p2). 1623 return false; 1624 } else { 1625 // Perform the conversion. 1626 // FIXME: Binding to a subobject of the lvalue is going to require 1627 // more AST annotation than this. 1628 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1629 } 1630 } 1631 1632 // -- has a class type (i.e., T2 is a class type) and can be 1633 // implicitly converted to an lvalue of type “cv3 T3,” 1634 // where “cv1 T1” is reference-compatible with “cv3 T3” 1635 // 92) (this conversion is selected by enumerating the 1636 // applicable conversion functions (13.3.1.6) and choosing 1637 // the best one through overload resolution (13.3)), 1638 if (!SuppressUserConversions && T2->isRecordType()) { 1639 // FIXME: Look for conversions in base classes! 1640 CXXRecordDecl *T2RecordDecl 1641 = dyn_cast<CXXRecordDecl>(T2->getAsRecordType()->getDecl()); 1642 1643 OverloadCandidateSet CandidateSet; 1644 OverloadedFunctionDecl *Conversions 1645 = T2RecordDecl->getConversionFunctions(); 1646 for (OverloadedFunctionDecl::function_iterator Func 1647 = Conversions->function_begin(); 1648 Func != Conversions->function_end(); ++Func) { 1649 CXXConversionDecl *Conv = cast<CXXConversionDecl>(*Func); 1650 1651 // If the conversion function doesn't return a reference type, 1652 // it can't be considered for this conversion. 1653 // FIXME: This will change when we support rvalue references. 1654 if (Conv->getConversionType()->isReferenceType()) 1655 AddConversionCandidate(Conv, Init, DeclType, CandidateSet); 1656 } 1657 1658 OverloadCandidateSet::iterator Best; 1659 switch (BestViableFunction(CandidateSet, Best)) { 1660 case OR_Success: 1661 // This is a direct binding. 1662 BindsDirectly = true; 1663 1664 if (ICS) { 1665 // C++ [over.ics.ref]p1: 1666 // 1667 // [...] If the parameter binds directly to the result of 1668 // applying a conversion function to the argument 1669 // expression, the implicit conversion sequence is a 1670 // user-defined conversion sequence (13.3.3.1.2), with the 1671 // second standard conversion sequence either an identity 1672 // conversion or, if the conversion function returns an 1673 // entity of a type that is a derived class of the parameter 1674 // type, a derived-to-base Conversion. 1675 ICS->ConversionKind = ImplicitConversionSequence::UserDefinedConversion; 1676 ICS->UserDefined.Before = Best->Conversions[0].Standard; 1677 ICS->UserDefined.After = Best->FinalConversion; 1678 ICS->UserDefined.ConversionFunction = Best->Function; 1679 assert(ICS->UserDefined.After.ReferenceBinding && 1680 ICS->UserDefined.After.DirectBinding && 1681 "Expected a direct reference binding!"); 1682 return false; 1683 } else { 1684 // Perform the conversion. 1685 // FIXME: Binding to a subobject of the lvalue is going to require 1686 // more AST annotation than this. 1687 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1688 } 1689 break; 1690 1691 case OR_Ambiguous: 1692 assert(false && "Ambiguous reference binding conversions not implemented."); 1693 return true; 1694 1695 case OR_No_Viable_Function: 1696 // There was no suitable conversion; continue with other checks. 1697 break; 1698 } 1699 } 1700 1701 if (BindsDirectly) { 1702 // C++ [dcl.init.ref]p4: 1703 // [...] In all cases where the reference-related or 1704 // reference-compatible relationship of two types is used to 1705 // establish the validity of a reference binding, and T1 is a 1706 // base class of T2, a program that necessitates such a binding 1707 // is ill-formed if T1 is an inaccessible (clause 11) or 1708 // ambiguous (10.2) base class of T2. 1709 // 1710 // Note that we only check this condition when we're allowed to 1711 // complain about errors, because we should not be checking for 1712 // ambiguity (or inaccessibility) unless the reference binding 1713 // actually happens. 1714 if (DerivedToBase) 1715 return CheckDerivedToBaseConversion(T2, T1, 1716 Init->getSourceRange().getBegin(), 1717 Init->getSourceRange()); 1718 else 1719 return false; 1720 } 1721 1722 // -- Otherwise, the reference shall be to a non-volatile const 1723 // type (i.e., cv1 shall be const). 1724 if (T1.getCVRQualifiers() != QualType::Const) { 1725 if (!ICS) 1726 Diag(Init->getSourceRange().getBegin(), 1727 diag::err_not_reference_to_const_init, 1728 T1.getAsString(), 1729 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1730 T2.getAsString(), Init->getSourceRange()); 1731 return true; 1732 } 1733 1734 // -- If the initializer expression is an rvalue, with T2 a 1735 // class type, and “cv1 T1” is reference-compatible with 1736 // “cv2 T2,” the reference is bound in one of the 1737 // following ways (the choice is implementation-defined): 1738 // 1739 // -- The reference is bound to the object represented by 1740 // the rvalue (see 3.10) or to a sub-object within that 1741 // object. 1742 // 1743 // -- A temporary of type “cv1 T2” [sic] is created, and 1744 // a constructor is called to copy the entire rvalue 1745 // object into the temporary. The reference is bound to 1746 // the temporary or to a sub-object within the 1747 // temporary. 1748 // 1749 // 1750 // The constructor that would be used to make the copy 1751 // shall be callable whether or not the copy is actually 1752 // done. 1753 // 1754 // Note that C++0x [dcl.ref.init]p5 takes away this implementation 1755 // freedom, so we will always take the first option and never build 1756 // a temporary in this case. FIXME: We will, however, have to check 1757 // for the presence of a copy constructor in C++98/03 mode. 1758 if (InitLvalue != Expr::LV_Valid && T2->isRecordType() && 1759 RefRelationship >= Ref_Compatible_With_Added_Qualification) { 1760 if (ICS) { 1761 ICS->ConversionKind = ImplicitConversionSequence::StandardConversion; 1762 ICS->Standard.First = ICK_Identity; 1763 ICS->Standard.Second = DerivedToBase? ICK_Derived_To_Base : ICK_Identity; 1764 ICS->Standard.Third = ICK_Identity; 1765 ICS->Standard.FromTypePtr = T2.getAsOpaquePtr(); 1766 ICS->Standard.ToTypePtr = T1.getAsOpaquePtr(); 1767 ICS->Standard.ReferenceBinding = true; 1768 ICS->Standard.DirectBinding = false; 1769 } else { 1770 // FIXME: Binding to a subobject of the rvalue is going to require 1771 // more AST annotation than this. 1772 ImpCastExprToType(Init, T1, /*isLvalue=*/true); 1773 } 1774 return false; 1775 } 1776 1777 // -- Otherwise, a temporary of type “cv1 T1” is created and 1778 // initialized from the initializer expression using the 1779 // rules for a non-reference copy initialization (8.5). The 1780 // reference is then bound to the temporary. If T1 is 1781 // reference-related to T2, cv1 must be the same 1782 // cv-qualification as, or greater cv-qualification than, 1783 // cv2; otherwise, the program is ill-formed. 1784 if (RefRelationship == Ref_Related) { 1785 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 1786 // we would be reference-compatible or reference-compatible with 1787 // added qualification. But that wasn't the case, so the reference 1788 // initialization fails. 1789 if (!ICS) 1790 Diag(Init->getSourceRange().getBegin(), 1791 diag::err_reference_init_drops_quals, 1792 T1.getAsString(), 1793 InitLvalue != Expr::LV_Valid? "temporary" : "value", 1794 T2.getAsString(), Init->getSourceRange()); 1795 return true; 1796 } 1797 1798 // Actually try to convert the initializer to T1. 1799 if (ICS) { 1800 /// C++ [over.ics.ref]p2: 1801 /// 1802 /// When a parameter of reference type is not bound directly to 1803 /// an argument expression, the conversion sequence is the one 1804 /// required to convert the argument expression to the 1805 /// underlying type of the reference according to 1806 /// 13.3.3.1. Conceptually, this conversion sequence corresponds 1807 /// to copy-initializing a temporary of the underlying type with 1808 /// the argument expression. Any difference in top-level 1809 /// cv-qualification is subsumed by the initialization itself 1810 /// and does not constitute a conversion. 1811 *ICS = TryImplicitConversion(Init, T1, SuppressUserConversions); 1812 return ICS->ConversionKind == ImplicitConversionSequence::BadConversion; 1813 } else { 1814 return PerformImplicitConversion(Init, T1); 1815 } 1816} 1817 1818/// CheckOverloadedOperatorDeclaration - Check whether the declaration 1819/// of this overloaded operator is well-formed. If so, returns false; 1820/// otherwise, emits appropriate diagnostics and returns true. 1821bool Sema::CheckOverloadedOperatorDeclaration(FunctionDecl *FnDecl) { 1822 assert(FnDecl && FnDecl->getOverloadedOperator() != OO_None && 1823 "Expected an overloaded operator declaration"); 1824 1825 bool IsInvalid = false; 1826 1827 OverloadedOperatorKind Op = FnDecl->getOverloadedOperator(); 1828 1829 // C++ [over.oper]p5: 1830 // The allocation and deallocation functions, operator new, 1831 // operator new[], operator delete and operator delete[], are 1832 // described completely in 3.7.3. The attributes and restrictions 1833 // found in the rest of this subclause do not apply to them unless 1834 // explicitly stated in 3.7.3. 1835 // FIXME: Write a separate routine for checking this. For now, just 1836 // allow it. 1837 if (Op == OO_New || Op == OO_Array_New || 1838 Op == OO_Delete || Op == OO_Array_Delete) 1839 return false; 1840 1841 // C++ [over.oper]p6: 1842 // An operator function shall either be a non-static member 1843 // function or be a non-member function and have at least one 1844 // parameter whose type is a class, a reference to a class, an 1845 // enumeration, or a reference to an enumeration. 1846 CXXMethodDecl *MethodDecl = dyn_cast<CXXMethodDecl>(FnDecl); 1847 if (MethodDecl) { 1848 if (MethodDecl->isStatic()) { 1849 Diag(FnDecl->getLocation(), 1850 diag::err_operator_overload_static, 1851 FnDecl->getName(), 1852 SourceRange(FnDecl->getLocation())); 1853 IsInvalid = true; 1854 1855 // Pretend this isn't a member function; it'll supress 1856 // additional, unnecessary error messages. 1857 MethodDecl = 0; 1858 } 1859 } else { 1860 bool ClassOrEnumParam = false; 1861 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 1862 Param != FnDecl->param_end(); ++Param) { 1863 QualType ParamType = (*Param)->getType(); 1864 if (const ReferenceType *RefType = ParamType->getAsReferenceType()) 1865 ParamType = RefType->getPointeeType(); 1866 if (ParamType->isRecordType() || ParamType->isEnumeralType()) { 1867 ClassOrEnumParam = true; 1868 break; 1869 } 1870 } 1871 1872 if (!ClassOrEnumParam) { 1873 Diag(FnDecl->getLocation(), 1874 diag::err_operator_overload_needs_class_or_enum, 1875 FnDecl->getName(), 1876 SourceRange(FnDecl->getLocation())); 1877 IsInvalid = true; 1878 } 1879 } 1880 1881 // C++ [over.oper]p8: 1882 // An operator function cannot have default arguments (8.3.6), 1883 // except where explicitly stated below. 1884 // 1885 // Only the function-call operator allows default arguments 1886 // (C++ [over.call]p1). 1887 if (Op != OO_Call) { 1888 for (FunctionDecl::param_iterator Param = FnDecl->param_begin(); 1889 Param != FnDecl->param_end(); ++Param) { 1890 if (Expr *DefArg = (*Param)->getDefaultArg()) { 1891 Diag((*Param)->getLocation(), 1892 diag::err_operator_overload_default_arg, 1893 DefArg->getSourceRange()); 1894 IsInvalid = true; 1895 } 1896 } 1897 } 1898 1899 static const bool OperatorUses[NUM_OVERLOADED_OPERATORS][3] = { 1900 { false, false, false } 1901#define OVERLOADED_OPERATOR(Name,Spelling,Token,Unary,Binary,MemberOnly) \ 1902 , { Unary, Binary, MemberOnly } 1903#include "clang/Basic/OperatorKinds.def" 1904 }; 1905 1906 bool CanBeUnaryOperator = OperatorUses[Op][0]; 1907 bool CanBeBinaryOperator = OperatorUses[Op][1]; 1908 bool MustBeMemberOperator = OperatorUses[Op][2]; 1909 1910 // C++ [over.oper]p8: 1911 // [...] Operator functions cannot have more or fewer parameters 1912 // than the number required for the corresponding operator, as 1913 // described in the rest of this subclause. 1914 unsigned NumParams = FnDecl->getNumParams() + (MethodDecl? 1 : 0); 1915 if (Op != OO_Call && 1916 ((NumParams == 1 && !CanBeUnaryOperator) || 1917 (NumParams == 2 && !CanBeBinaryOperator) || 1918 (NumParams < 1) || (NumParams > 2))) { 1919 // We have the wrong number of parameters. 1920 std::string NumParamsStr = (llvm::APSInt(32) = NumParams).toString(10); 1921 1922 diag::kind DK; 1923 1924 if (CanBeUnaryOperator && CanBeBinaryOperator) { 1925 if (NumParams == 1) 1926 DK = diag::err_operator_overload_must_be_unary_or_binary; 1927 else 1928 DK = diag::err_operator_overload_must_be_unary_or_binary; 1929 } else if (CanBeUnaryOperator) { 1930 if (NumParams == 1) 1931 DK = diag::err_operator_overload_must_be_unary; 1932 else 1933 DK = diag::err_operator_overload_must_be_unary_plural; 1934 } else if (CanBeBinaryOperator) { 1935 if (NumParams == 1) 1936 DK = diag::err_operator_overload_must_be_binary; 1937 else 1938 DK = diag::err_operator_overload_must_be_binary_plural; 1939 } else { 1940 assert(false && "All non-call overloaded operators are unary or binary!"); 1941 } 1942 1943 Diag(FnDecl->getLocation(), DK, 1944 FnDecl->getName(), NumParamsStr, 1945 SourceRange(FnDecl->getLocation())); 1946 IsInvalid = true; 1947 } 1948 1949 // Overloaded operators cannot be variadic. 1950 if (FnDecl->getType()->getAsFunctionTypeProto()->isVariadic()) { 1951 Diag(FnDecl->getLocation(), 1952 diag::err_operator_overload_variadic, 1953 SourceRange(FnDecl->getLocation())); 1954 IsInvalid = true; 1955 } 1956 1957 // Some operators must be non-static member functions. 1958 if (MustBeMemberOperator && !MethodDecl) { 1959 Diag(FnDecl->getLocation(), 1960 diag::err_operator_overload_must_be_member, 1961 FnDecl->getName(), 1962 SourceRange(FnDecl->getLocation())); 1963 IsInvalid = true; 1964 } 1965 1966 // C++ [over.inc]p1: 1967 // The user-defined function called operator++ implements the 1968 // prefix and postfix ++ operator. If this function is a member 1969 // function with no parameters, or a non-member function with one 1970 // parameter of class or enumeration type, it defines the prefix 1971 // increment operator ++ for objects of that type. If the function 1972 // is a member function with one parameter (which shall be of type 1973 // int) or a non-member function with two parameters (the second 1974 // of which shall be of type int), it defines the postfix 1975 // increment operator ++ for objects of that type. 1976 if ((Op == OO_PlusPlus || Op == OO_MinusMinus) && NumParams == 2) { 1977 ParmVarDecl *LastParam = FnDecl->getParamDecl(FnDecl->getNumParams() - 1); 1978 bool ParamIsInt = false; 1979 if (const BuiltinType *BT = LastParam->getType()->getAsBuiltinType()) 1980 ParamIsInt = BT->getKind() == BuiltinType::Int; 1981 1982 if (!ParamIsInt) { 1983 diag::kind DK; 1984 if (Op == OO_PlusPlus) { 1985 if (MethodDecl) 1986 DK = diag::err_operator_overload_post_inc_must_be_int_member; 1987 else 1988 DK = diag::err_operator_overload_post_inc_must_be_int; 1989 } else { 1990 if (MethodDecl) 1991 DK = diag::err_operator_overload_post_dec_must_be_int_member; 1992 else 1993 DK = diag::err_operator_overload_post_dec_must_be_int; 1994 } 1995 Diag(LastParam->getLocation(), DK, 1996 Context.getCanonicalType(LastParam->getType()).getAsString(), 1997 SourceRange(FnDecl->getLocation())); 1998 IsInvalid = true; 1999 } 2000 } 2001 2002 return IsInvalid; 2003} 2004