SemaOverload.cpp revision ace5e76e5c707f4a8447abc01ef540fa6d57ff95
1//===--- SemaOverload.cpp - C++ Overloading ---------------------*- C++ -*-===// 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 provides Sema routines for C++ overloading. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Lookup.h" 16#include "clang/Sema/Initialization.h" 17#include "clang/Sema/Template.h" 18#include "clang/Sema/TemplateDeduction.h" 19#include "clang/Basic/Diagnostic.h" 20#include "clang/Lex/Preprocessor.h" 21#include "clang/AST/ASTContext.h" 22#include "clang/AST/CXXInheritance.h" 23#include "clang/AST/DeclObjC.h" 24#include "clang/AST/Expr.h" 25#include "clang/AST/ExprCXX.h" 26#include "clang/AST/ExprObjC.h" 27#include "clang/AST/TypeOrdering.h" 28#include "clang/Basic/PartialDiagnostic.h" 29#include "llvm/ADT/DenseSet.h" 30#include "llvm/ADT/SmallPtrSet.h" 31#include "llvm/ADT/STLExtras.h" 32#include <algorithm> 33 34namespace clang { 35using namespace sema; 36 37/// A convenience routine for creating a decayed reference to a 38/// function. 39static ExprResult 40CreateFunctionRefExpr(Sema &S, FunctionDecl *Fn, 41 SourceLocation Loc = SourceLocation(), 42 const DeclarationNameLoc &LocInfo = DeclarationNameLoc()){ 43 ExprResult E = S.Owned(new (S.Context) DeclRefExpr(Fn, Fn->getType(), 44 VK_LValue, Loc, LocInfo)); 45 E = S.DefaultFunctionArrayConversion(E.take()); 46 if (E.isInvalid()) 47 return ExprError(); 48 return move(E); 49} 50 51static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType, 52 bool InOverloadResolution, 53 StandardConversionSequence &SCS, 54 bool CStyle, 55 bool AllowObjCWritebackConversion); 56 57static bool IsTransparentUnionStandardConversion(Sema &S, Expr* From, 58 QualType &ToType, 59 bool InOverloadResolution, 60 StandardConversionSequence &SCS, 61 bool CStyle); 62static OverloadingResult 63IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 64 UserDefinedConversionSequence& User, 65 OverloadCandidateSet& Conversions, 66 bool AllowExplicit); 67 68 69static ImplicitConversionSequence::CompareKind 70CompareStandardConversionSequences(Sema &S, 71 const StandardConversionSequence& SCS1, 72 const StandardConversionSequence& SCS2); 73 74static ImplicitConversionSequence::CompareKind 75CompareQualificationConversions(Sema &S, 76 const StandardConversionSequence& SCS1, 77 const StandardConversionSequence& SCS2); 78 79static ImplicitConversionSequence::CompareKind 80CompareDerivedToBaseConversions(Sema &S, 81 const StandardConversionSequence& SCS1, 82 const StandardConversionSequence& SCS2); 83 84 85 86/// GetConversionCategory - Retrieve the implicit conversion 87/// category corresponding to the given implicit conversion kind. 88ImplicitConversionCategory 89GetConversionCategory(ImplicitConversionKind Kind) { 90 static const ImplicitConversionCategory 91 Category[(int)ICK_Num_Conversion_Kinds] = { 92 ICC_Identity, 93 ICC_Lvalue_Transformation, 94 ICC_Lvalue_Transformation, 95 ICC_Lvalue_Transformation, 96 ICC_Identity, 97 ICC_Qualification_Adjustment, 98 ICC_Promotion, 99 ICC_Promotion, 100 ICC_Promotion, 101 ICC_Conversion, 102 ICC_Conversion, 103 ICC_Conversion, 104 ICC_Conversion, 105 ICC_Conversion, 106 ICC_Conversion, 107 ICC_Conversion, 108 ICC_Conversion, 109 ICC_Conversion, 110 ICC_Conversion, 111 ICC_Conversion, 112 ICC_Conversion, 113 ICC_Conversion 114 }; 115 return Category[(int)Kind]; 116} 117 118/// GetConversionRank - Retrieve the implicit conversion rank 119/// corresponding to the given implicit conversion kind. 120ImplicitConversionRank GetConversionRank(ImplicitConversionKind Kind) { 121 static const ImplicitConversionRank 122 Rank[(int)ICK_Num_Conversion_Kinds] = { 123 ICR_Exact_Match, 124 ICR_Exact_Match, 125 ICR_Exact_Match, 126 ICR_Exact_Match, 127 ICR_Exact_Match, 128 ICR_Exact_Match, 129 ICR_Promotion, 130 ICR_Promotion, 131 ICR_Promotion, 132 ICR_Conversion, 133 ICR_Conversion, 134 ICR_Conversion, 135 ICR_Conversion, 136 ICR_Conversion, 137 ICR_Conversion, 138 ICR_Conversion, 139 ICR_Conversion, 140 ICR_Conversion, 141 ICR_Conversion, 142 ICR_Conversion, 143 ICR_Complex_Real_Conversion, 144 ICR_Conversion, 145 ICR_Conversion, 146 ICR_Writeback_Conversion 147 }; 148 return Rank[(int)Kind]; 149} 150 151/// GetImplicitConversionName - Return the name of this kind of 152/// implicit conversion. 153const char* GetImplicitConversionName(ImplicitConversionKind Kind) { 154 static const char* const Name[(int)ICK_Num_Conversion_Kinds] = { 155 "No conversion", 156 "Lvalue-to-rvalue", 157 "Array-to-pointer", 158 "Function-to-pointer", 159 "Noreturn adjustment", 160 "Qualification", 161 "Integral promotion", 162 "Floating point promotion", 163 "Complex promotion", 164 "Integral conversion", 165 "Floating conversion", 166 "Complex conversion", 167 "Floating-integral conversion", 168 "Pointer conversion", 169 "Pointer-to-member conversion", 170 "Boolean conversion", 171 "Compatible-types conversion", 172 "Derived-to-base conversion", 173 "Vector conversion", 174 "Vector splat", 175 "Complex-real conversion", 176 "Block Pointer conversion", 177 "Transparent Union Conversion" 178 "Writeback conversion" 179 }; 180 return Name[Kind]; 181} 182 183/// StandardConversionSequence - Set the standard conversion 184/// sequence to the identity conversion. 185void StandardConversionSequence::setAsIdentityConversion() { 186 First = ICK_Identity; 187 Second = ICK_Identity; 188 Third = ICK_Identity; 189 DeprecatedStringLiteralToCharPtr = false; 190 QualificationIncludesObjCLifetime = false; 191 ReferenceBinding = false; 192 DirectBinding = false; 193 IsLvalueReference = true; 194 BindsToFunctionLvalue = false; 195 BindsToRvalue = false; 196 BindsImplicitObjectArgumentWithoutRefQualifier = false; 197 ObjCLifetimeConversionBinding = false; 198 CopyConstructor = 0; 199} 200 201/// getRank - Retrieve the rank of this standard conversion sequence 202/// (C++ 13.3.3.1.1p3). The rank is the largest rank of each of the 203/// implicit conversions. 204ImplicitConversionRank StandardConversionSequence::getRank() const { 205 ImplicitConversionRank Rank = ICR_Exact_Match; 206 if (GetConversionRank(First) > Rank) 207 Rank = GetConversionRank(First); 208 if (GetConversionRank(Second) > Rank) 209 Rank = GetConversionRank(Second); 210 if (GetConversionRank(Third) > Rank) 211 Rank = GetConversionRank(Third); 212 return Rank; 213} 214 215/// isPointerConversionToBool - Determines whether this conversion is 216/// a conversion of a pointer or pointer-to-member to bool. This is 217/// used as part of the ranking of standard conversion sequences 218/// (C++ 13.3.3.2p4). 219bool StandardConversionSequence::isPointerConversionToBool() const { 220 // Note that FromType has not necessarily been transformed by the 221 // array-to-pointer or function-to-pointer implicit conversions, so 222 // check for their presence as well as checking whether FromType is 223 // a pointer. 224 if (getToType(1)->isBooleanType() && 225 (getFromType()->isPointerType() || 226 getFromType()->isObjCObjectPointerType() || 227 getFromType()->isBlockPointerType() || 228 getFromType()->isNullPtrType() || 229 First == ICK_Array_To_Pointer || First == ICK_Function_To_Pointer)) 230 return true; 231 232 return false; 233} 234 235/// isPointerConversionToVoidPointer - Determines whether this 236/// conversion is a conversion of a pointer to a void pointer. This is 237/// used as part of the ranking of standard conversion sequences (C++ 238/// 13.3.3.2p4). 239bool 240StandardConversionSequence:: 241isPointerConversionToVoidPointer(ASTContext& Context) const { 242 QualType FromType = getFromType(); 243 QualType ToType = getToType(1); 244 245 // Note that FromType has not necessarily been transformed by the 246 // array-to-pointer implicit conversion, so check for its presence 247 // and redo the conversion to get a pointer. 248 if (First == ICK_Array_To_Pointer) 249 FromType = Context.getArrayDecayedType(FromType); 250 251 if (Second == ICK_Pointer_Conversion && FromType->isAnyPointerType()) 252 if (const PointerType* ToPtrType = ToType->getAs<PointerType>()) 253 return ToPtrType->getPointeeType()->isVoidType(); 254 255 return false; 256} 257 258/// DebugPrint - Print this standard conversion sequence to standard 259/// error. Useful for debugging overloading issues. 260void StandardConversionSequence::DebugPrint() const { 261 raw_ostream &OS = llvm::errs(); 262 bool PrintedSomething = false; 263 if (First != ICK_Identity) { 264 OS << GetImplicitConversionName(First); 265 PrintedSomething = true; 266 } 267 268 if (Second != ICK_Identity) { 269 if (PrintedSomething) { 270 OS << " -> "; 271 } 272 OS << GetImplicitConversionName(Second); 273 274 if (CopyConstructor) { 275 OS << " (by copy constructor)"; 276 } else if (DirectBinding) { 277 OS << " (direct reference binding)"; 278 } else if (ReferenceBinding) { 279 OS << " (reference binding)"; 280 } 281 PrintedSomething = true; 282 } 283 284 if (Third != ICK_Identity) { 285 if (PrintedSomething) { 286 OS << " -> "; 287 } 288 OS << GetImplicitConversionName(Third); 289 PrintedSomething = true; 290 } 291 292 if (!PrintedSomething) { 293 OS << "No conversions required"; 294 } 295} 296 297/// DebugPrint - Print this user-defined conversion sequence to standard 298/// error. Useful for debugging overloading issues. 299void UserDefinedConversionSequence::DebugPrint() const { 300 raw_ostream &OS = llvm::errs(); 301 if (Before.First || Before.Second || Before.Third) { 302 Before.DebugPrint(); 303 OS << " -> "; 304 } 305 OS << '\'' << ConversionFunction << '\''; 306 if (After.First || After.Second || After.Third) { 307 OS << " -> "; 308 After.DebugPrint(); 309 } 310} 311 312/// DebugPrint - Print this implicit conversion sequence to standard 313/// error. Useful for debugging overloading issues. 314void ImplicitConversionSequence::DebugPrint() const { 315 raw_ostream &OS = llvm::errs(); 316 switch (ConversionKind) { 317 case StandardConversion: 318 OS << "Standard conversion: "; 319 Standard.DebugPrint(); 320 break; 321 case UserDefinedConversion: 322 OS << "User-defined conversion: "; 323 UserDefined.DebugPrint(); 324 break; 325 case EllipsisConversion: 326 OS << "Ellipsis conversion"; 327 break; 328 case AmbiguousConversion: 329 OS << "Ambiguous conversion"; 330 break; 331 case BadConversion: 332 OS << "Bad conversion"; 333 break; 334 } 335 336 OS << "\n"; 337} 338 339void AmbiguousConversionSequence::construct() { 340 new (&conversions()) ConversionSet(); 341} 342 343void AmbiguousConversionSequence::destruct() { 344 conversions().~ConversionSet(); 345} 346 347void 348AmbiguousConversionSequence::copyFrom(const AmbiguousConversionSequence &O) { 349 FromTypePtr = O.FromTypePtr; 350 ToTypePtr = O.ToTypePtr; 351 new (&conversions()) ConversionSet(O.conversions()); 352} 353 354namespace { 355 // Structure used by OverloadCandidate::DeductionFailureInfo to store 356 // template parameter and template argument information. 357 struct DFIParamWithArguments { 358 TemplateParameter Param; 359 TemplateArgument FirstArg; 360 TemplateArgument SecondArg; 361 }; 362} 363 364/// \brief Convert from Sema's representation of template deduction information 365/// to the form used in overload-candidate information. 366OverloadCandidate::DeductionFailureInfo 367static MakeDeductionFailureInfo(ASTContext &Context, 368 Sema::TemplateDeductionResult TDK, 369 TemplateDeductionInfo &Info) { 370 OverloadCandidate::DeductionFailureInfo Result; 371 Result.Result = static_cast<unsigned>(TDK); 372 Result.Data = 0; 373 switch (TDK) { 374 case Sema::TDK_Success: 375 case Sema::TDK_InstantiationDepth: 376 case Sema::TDK_TooManyArguments: 377 case Sema::TDK_TooFewArguments: 378 break; 379 380 case Sema::TDK_Incomplete: 381 case Sema::TDK_InvalidExplicitArguments: 382 Result.Data = Info.Param.getOpaqueValue(); 383 break; 384 385 case Sema::TDK_Inconsistent: 386 case Sema::TDK_Underqualified: { 387 // FIXME: Should allocate from normal heap so that we can free this later. 388 DFIParamWithArguments *Saved = new (Context) DFIParamWithArguments; 389 Saved->Param = Info.Param; 390 Saved->FirstArg = Info.FirstArg; 391 Saved->SecondArg = Info.SecondArg; 392 Result.Data = Saved; 393 break; 394 } 395 396 case Sema::TDK_SubstitutionFailure: 397 Result.Data = Info.take(); 398 break; 399 400 case Sema::TDK_NonDeducedMismatch: 401 case Sema::TDK_FailedOverloadResolution: 402 break; 403 } 404 405 return Result; 406} 407 408void OverloadCandidate::DeductionFailureInfo::Destroy() { 409 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 410 case Sema::TDK_Success: 411 case Sema::TDK_InstantiationDepth: 412 case Sema::TDK_Incomplete: 413 case Sema::TDK_TooManyArguments: 414 case Sema::TDK_TooFewArguments: 415 case Sema::TDK_InvalidExplicitArguments: 416 break; 417 418 case Sema::TDK_Inconsistent: 419 case Sema::TDK_Underqualified: 420 // FIXME: Destroy the data? 421 Data = 0; 422 break; 423 424 case Sema::TDK_SubstitutionFailure: 425 // FIXME: Destroy the template arugment list? 426 Data = 0; 427 break; 428 429 // Unhandled 430 case Sema::TDK_NonDeducedMismatch: 431 case Sema::TDK_FailedOverloadResolution: 432 break; 433 } 434} 435 436TemplateParameter 437OverloadCandidate::DeductionFailureInfo::getTemplateParameter() { 438 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 439 case Sema::TDK_Success: 440 case Sema::TDK_InstantiationDepth: 441 case Sema::TDK_TooManyArguments: 442 case Sema::TDK_TooFewArguments: 443 case Sema::TDK_SubstitutionFailure: 444 return TemplateParameter(); 445 446 case Sema::TDK_Incomplete: 447 case Sema::TDK_InvalidExplicitArguments: 448 return TemplateParameter::getFromOpaqueValue(Data); 449 450 case Sema::TDK_Inconsistent: 451 case Sema::TDK_Underqualified: 452 return static_cast<DFIParamWithArguments*>(Data)->Param; 453 454 // Unhandled 455 case Sema::TDK_NonDeducedMismatch: 456 case Sema::TDK_FailedOverloadResolution: 457 break; 458 } 459 460 return TemplateParameter(); 461} 462 463TemplateArgumentList * 464OverloadCandidate::DeductionFailureInfo::getTemplateArgumentList() { 465 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 466 case Sema::TDK_Success: 467 case Sema::TDK_InstantiationDepth: 468 case Sema::TDK_TooManyArguments: 469 case Sema::TDK_TooFewArguments: 470 case Sema::TDK_Incomplete: 471 case Sema::TDK_InvalidExplicitArguments: 472 case Sema::TDK_Inconsistent: 473 case Sema::TDK_Underqualified: 474 return 0; 475 476 case Sema::TDK_SubstitutionFailure: 477 return static_cast<TemplateArgumentList*>(Data); 478 479 // Unhandled 480 case Sema::TDK_NonDeducedMismatch: 481 case Sema::TDK_FailedOverloadResolution: 482 break; 483 } 484 485 return 0; 486} 487 488const TemplateArgument *OverloadCandidate::DeductionFailureInfo::getFirstArg() { 489 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 490 case Sema::TDK_Success: 491 case Sema::TDK_InstantiationDepth: 492 case Sema::TDK_Incomplete: 493 case Sema::TDK_TooManyArguments: 494 case Sema::TDK_TooFewArguments: 495 case Sema::TDK_InvalidExplicitArguments: 496 case Sema::TDK_SubstitutionFailure: 497 return 0; 498 499 case Sema::TDK_Inconsistent: 500 case Sema::TDK_Underqualified: 501 return &static_cast<DFIParamWithArguments*>(Data)->FirstArg; 502 503 // Unhandled 504 case Sema::TDK_NonDeducedMismatch: 505 case Sema::TDK_FailedOverloadResolution: 506 break; 507 } 508 509 return 0; 510} 511 512const TemplateArgument * 513OverloadCandidate::DeductionFailureInfo::getSecondArg() { 514 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 515 case Sema::TDK_Success: 516 case Sema::TDK_InstantiationDepth: 517 case Sema::TDK_Incomplete: 518 case Sema::TDK_TooManyArguments: 519 case Sema::TDK_TooFewArguments: 520 case Sema::TDK_InvalidExplicitArguments: 521 case Sema::TDK_SubstitutionFailure: 522 return 0; 523 524 case Sema::TDK_Inconsistent: 525 case Sema::TDK_Underqualified: 526 return &static_cast<DFIParamWithArguments*>(Data)->SecondArg; 527 528 // Unhandled 529 case Sema::TDK_NonDeducedMismatch: 530 case Sema::TDK_FailedOverloadResolution: 531 break; 532 } 533 534 return 0; 535} 536 537void OverloadCandidateSet::clear() { 538 inherited::clear(); 539 Functions.clear(); 540} 541 542// IsOverload - Determine whether the given New declaration is an 543// overload of the declarations in Old. This routine returns false if 544// New and Old cannot be overloaded, e.g., if New has the same 545// signature as some function in Old (C++ 1.3.10) or if the Old 546// declarations aren't functions (or function templates) at all. When 547// it does return false, MatchedDecl will point to the decl that New 548// cannot be overloaded with. This decl may be a UsingShadowDecl on 549// top of the underlying declaration. 550// 551// Example: Given the following input: 552// 553// void f(int, float); // #1 554// void f(int, int); // #2 555// int f(int, int); // #3 556// 557// When we process #1, there is no previous declaration of "f", 558// so IsOverload will not be used. 559// 560// When we process #2, Old contains only the FunctionDecl for #1. By 561// comparing the parameter types, we see that #1 and #2 are overloaded 562// (since they have different signatures), so this routine returns 563// false; MatchedDecl is unchanged. 564// 565// When we process #3, Old is an overload set containing #1 and #2. We 566// compare the signatures of #3 to #1 (they're overloaded, so we do 567// nothing) and then #3 to #2. Since the signatures of #3 and #2 are 568// identical (return types of functions are not part of the 569// signature), IsOverload returns false and MatchedDecl will be set to 570// point to the FunctionDecl for #2. 571// 572// 'NewIsUsingShadowDecl' indicates that 'New' is being introduced 573// into a class by a using declaration. The rules for whether to hide 574// shadow declarations ignore some properties which otherwise figure 575// into a function template's signature. 576Sema::OverloadKind 577Sema::CheckOverload(Scope *S, FunctionDecl *New, const LookupResult &Old, 578 NamedDecl *&Match, bool NewIsUsingDecl) { 579 for (LookupResult::iterator I = Old.begin(), E = Old.end(); 580 I != E; ++I) { 581 NamedDecl *OldD = *I; 582 583 bool OldIsUsingDecl = false; 584 if (isa<UsingShadowDecl>(OldD)) { 585 OldIsUsingDecl = true; 586 587 // We can always introduce two using declarations into the same 588 // context, even if they have identical signatures. 589 if (NewIsUsingDecl) continue; 590 591 OldD = cast<UsingShadowDecl>(OldD)->getTargetDecl(); 592 } 593 594 // If either declaration was introduced by a using declaration, 595 // we'll need to use slightly different rules for matching. 596 // Essentially, these rules are the normal rules, except that 597 // function templates hide function templates with different 598 // return types or template parameter lists. 599 bool UseMemberUsingDeclRules = 600 (OldIsUsingDecl || NewIsUsingDecl) && CurContext->isRecord(); 601 602 if (FunctionTemplateDecl *OldT = dyn_cast<FunctionTemplateDecl>(OldD)) { 603 if (!IsOverload(New, OldT->getTemplatedDecl(), UseMemberUsingDeclRules)) { 604 if (UseMemberUsingDeclRules && OldIsUsingDecl) { 605 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I)); 606 continue; 607 } 608 609 Match = *I; 610 return Ovl_Match; 611 } 612 } else if (FunctionDecl *OldF = dyn_cast<FunctionDecl>(OldD)) { 613 if (!IsOverload(New, OldF, UseMemberUsingDeclRules)) { 614 if (UseMemberUsingDeclRules && OldIsUsingDecl) { 615 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I)); 616 continue; 617 } 618 619 Match = *I; 620 return Ovl_Match; 621 } 622 } else if (isa<UsingDecl>(OldD)) { 623 // We can overload with these, which can show up when doing 624 // redeclaration checks for UsingDecls. 625 assert(Old.getLookupKind() == LookupUsingDeclName); 626 } else if (isa<TagDecl>(OldD)) { 627 // We can always overload with tags by hiding them. 628 } else if (isa<UnresolvedUsingValueDecl>(OldD)) { 629 // Optimistically assume that an unresolved using decl will 630 // overload; if it doesn't, we'll have to diagnose during 631 // template instantiation. 632 } else { 633 // (C++ 13p1): 634 // Only function declarations can be overloaded; object and type 635 // declarations cannot be overloaded. 636 Match = *I; 637 return Ovl_NonFunction; 638 } 639 } 640 641 return Ovl_Overload; 642} 643 644bool Sema::IsOverload(FunctionDecl *New, FunctionDecl *Old, 645 bool UseUsingDeclRules) { 646 // If both of the functions are extern "C", then they are not 647 // overloads. 648 if (Old->isExternC() && New->isExternC()) 649 return false; 650 651 FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate(); 652 FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate(); 653 654 // C++ [temp.fct]p2: 655 // A function template can be overloaded with other function templates 656 // and with normal (non-template) functions. 657 if ((OldTemplate == 0) != (NewTemplate == 0)) 658 return true; 659 660 // Is the function New an overload of the function Old? 661 QualType OldQType = Context.getCanonicalType(Old->getType()); 662 QualType NewQType = Context.getCanonicalType(New->getType()); 663 664 // Compare the signatures (C++ 1.3.10) of the two functions to 665 // determine whether they are overloads. If we find any mismatch 666 // in the signature, they are overloads. 667 668 // If either of these functions is a K&R-style function (no 669 // prototype), then we consider them to have matching signatures. 670 if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) || 671 isa<FunctionNoProtoType>(NewQType.getTypePtr())) 672 return false; 673 674 const FunctionProtoType* OldType = cast<FunctionProtoType>(OldQType); 675 const FunctionProtoType* NewType = cast<FunctionProtoType>(NewQType); 676 677 // The signature of a function includes the types of its 678 // parameters (C++ 1.3.10), which includes the presence or absence 679 // of the ellipsis; see C++ DR 357). 680 if (OldQType != NewQType && 681 (OldType->getNumArgs() != NewType->getNumArgs() || 682 OldType->isVariadic() != NewType->isVariadic() || 683 !FunctionArgTypesAreEqual(OldType, NewType))) 684 return true; 685 686 // C++ [temp.over.link]p4: 687 // The signature of a function template consists of its function 688 // signature, its return type and its template parameter list. The names 689 // of the template parameters are significant only for establishing the 690 // relationship between the template parameters and the rest of the 691 // signature. 692 // 693 // We check the return type and template parameter lists for function 694 // templates first; the remaining checks follow. 695 // 696 // However, we don't consider either of these when deciding whether 697 // a member introduced by a shadow declaration is hidden. 698 if (!UseUsingDeclRules && NewTemplate && 699 (!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(), 700 OldTemplate->getTemplateParameters(), 701 false, TPL_TemplateMatch) || 702 OldType->getResultType() != NewType->getResultType())) 703 return true; 704 705 // If the function is a class member, its signature includes the 706 // cv-qualifiers (if any) and ref-qualifier (if any) on the function itself. 707 // 708 // As part of this, also check whether one of the member functions 709 // is static, in which case they are not overloads (C++ 710 // 13.1p2). While not part of the definition of the signature, 711 // this check is important to determine whether these functions 712 // can be overloaded. 713 CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 714 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 715 if (OldMethod && NewMethod && 716 !OldMethod->isStatic() && !NewMethod->isStatic() && 717 (OldMethod->getTypeQualifiers() != NewMethod->getTypeQualifiers() || 718 OldMethod->getRefQualifier() != NewMethod->getRefQualifier())) { 719 if (!UseUsingDeclRules && 720 OldMethod->getRefQualifier() != NewMethod->getRefQualifier() && 721 (OldMethod->getRefQualifier() == RQ_None || 722 NewMethod->getRefQualifier() == RQ_None)) { 723 // C++0x [over.load]p2: 724 // - Member function declarations with the same name and the same 725 // parameter-type-list as well as member function template 726 // declarations with the same name, the same parameter-type-list, and 727 // the same template parameter lists cannot be overloaded if any of 728 // them, but not all, have a ref-qualifier (8.3.5). 729 Diag(NewMethod->getLocation(), diag::err_ref_qualifier_overload) 730 << NewMethod->getRefQualifier() << OldMethod->getRefQualifier(); 731 Diag(OldMethod->getLocation(), diag::note_previous_declaration); 732 } 733 734 return true; 735 } 736 737 // The signatures match; this is not an overload. 738 return false; 739} 740 741/// \brief Checks availability of the function depending on the current 742/// function context. Inside an unavailable function, unavailability is ignored. 743/// 744/// \returns true if \arg FD is unavailable and current context is inside 745/// an available function, false otherwise. 746bool Sema::isFunctionConsideredUnavailable(FunctionDecl *FD) { 747 return FD->isUnavailable() && !cast<Decl>(CurContext)->isUnavailable(); 748} 749 750/// TryImplicitConversion - Attempt to perform an implicit conversion 751/// from the given expression (Expr) to the given type (ToType). This 752/// function returns an implicit conversion sequence that can be used 753/// to perform the initialization. Given 754/// 755/// void f(float f); 756/// void g(int i) { f(i); } 757/// 758/// this routine would produce an implicit conversion sequence to 759/// describe the initialization of f from i, which will be a standard 760/// conversion sequence containing an lvalue-to-rvalue conversion (C++ 761/// 4.1) followed by a floating-integral conversion (C++ 4.9). 762// 763/// Note that this routine only determines how the conversion can be 764/// performed; it does not actually perform the conversion. As such, 765/// it will not produce any diagnostics if no conversion is available, 766/// but will instead return an implicit conversion sequence of kind 767/// "BadConversion". 768/// 769/// If @p SuppressUserConversions, then user-defined conversions are 770/// not permitted. 771/// If @p AllowExplicit, then explicit user-defined conversions are 772/// permitted. 773/// 774/// \param AllowObjCWritebackConversion Whether we allow the Objective-C 775/// writeback conversion, which allows __autoreleasing id* parameters to 776/// be initialized with __strong id* or __weak id* arguments. 777static ImplicitConversionSequence 778TryImplicitConversion(Sema &S, Expr *From, QualType ToType, 779 bool SuppressUserConversions, 780 bool AllowExplicit, 781 bool InOverloadResolution, 782 bool CStyle, 783 bool AllowObjCWritebackConversion) { 784 ImplicitConversionSequence ICS; 785 if (IsStandardConversion(S, From, ToType, InOverloadResolution, 786 ICS.Standard, CStyle, AllowObjCWritebackConversion)){ 787 ICS.setStandard(); 788 return ICS; 789 } 790 791 if (!S.getLangOptions().CPlusPlus) { 792 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 793 return ICS; 794 } 795 796 // C++ [over.ics.user]p4: 797 // A conversion of an expression of class type to the same class 798 // type is given Exact Match rank, and a conversion of an 799 // expression of class type to a base class of that type is 800 // given Conversion rank, in spite of the fact that a copy/move 801 // constructor (i.e., a user-defined conversion function) is 802 // called for those cases. 803 QualType FromType = From->getType(); 804 if (ToType->getAs<RecordType>() && FromType->getAs<RecordType>() && 805 (S.Context.hasSameUnqualifiedType(FromType, ToType) || 806 S.IsDerivedFrom(FromType, ToType))) { 807 ICS.setStandard(); 808 ICS.Standard.setAsIdentityConversion(); 809 ICS.Standard.setFromType(FromType); 810 ICS.Standard.setAllToTypes(ToType); 811 812 // We don't actually check at this point whether there is a valid 813 // copy/move constructor, since overloading just assumes that it 814 // exists. When we actually perform initialization, we'll find the 815 // appropriate constructor to copy the returned object, if needed. 816 ICS.Standard.CopyConstructor = 0; 817 818 // Determine whether this is considered a derived-to-base conversion. 819 if (!S.Context.hasSameUnqualifiedType(FromType, ToType)) 820 ICS.Standard.Second = ICK_Derived_To_Base; 821 822 return ICS; 823 } 824 825 if (SuppressUserConversions) { 826 // We're not in the case above, so there is no conversion that 827 // we can perform. 828 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 829 return ICS; 830 } 831 832 // Attempt user-defined conversion. 833 OverloadCandidateSet Conversions(From->getExprLoc()); 834 OverloadingResult UserDefResult 835 = IsUserDefinedConversion(S, From, ToType, ICS.UserDefined, Conversions, 836 AllowExplicit); 837 838 if (UserDefResult == OR_Success) { 839 ICS.setUserDefined(); 840 // C++ [over.ics.user]p4: 841 // A conversion of an expression of class type to the same class 842 // type is given Exact Match rank, and a conversion of an 843 // expression of class type to a base class of that type is 844 // given Conversion rank, in spite of the fact that a copy 845 // constructor (i.e., a user-defined conversion function) is 846 // called for those cases. 847 if (CXXConstructorDecl *Constructor 848 = dyn_cast<CXXConstructorDecl>(ICS.UserDefined.ConversionFunction)) { 849 QualType FromCanon 850 = S.Context.getCanonicalType(From->getType().getUnqualifiedType()); 851 QualType ToCanon 852 = S.Context.getCanonicalType(ToType).getUnqualifiedType(); 853 if (Constructor->isCopyConstructor() && 854 (FromCanon == ToCanon || S.IsDerivedFrom(FromCanon, ToCanon))) { 855 // Turn this into a "standard" conversion sequence, so that it 856 // gets ranked with standard conversion sequences. 857 ICS.setStandard(); 858 ICS.Standard.setAsIdentityConversion(); 859 ICS.Standard.setFromType(From->getType()); 860 ICS.Standard.setAllToTypes(ToType); 861 ICS.Standard.CopyConstructor = Constructor; 862 if (ToCanon != FromCanon) 863 ICS.Standard.Second = ICK_Derived_To_Base; 864 } 865 } 866 867 // C++ [over.best.ics]p4: 868 // However, when considering the argument of a user-defined 869 // conversion function that is a candidate by 13.3.1.3 when 870 // invoked for the copying of the temporary in the second step 871 // of a class copy-initialization, or by 13.3.1.4, 13.3.1.5, or 872 // 13.3.1.6 in all cases, only standard conversion sequences and 873 // ellipsis conversion sequences are allowed. 874 if (SuppressUserConversions && ICS.isUserDefined()) { 875 ICS.setBad(BadConversionSequence::suppressed_user, From, ToType); 876 } 877 } else if (UserDefResult == OR_Ambiguous && !SuppressUserConversions) { 878 ICS.setAmbiguous(); 879 ICS.Ambiguous.setFromType(From->getType()); 880 ICS.Ambiguous.setToType(ToType); 881 for (OverloadCandidateSet::iterator Cand = Conversions.begin(); 882 Cand != Conversions.end(); ++Cand) 883 if (Cand->Viable) 884 ICS.Ambiguous.addConversion(Cand->Function); 885 } else { 886 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 887 } 888 889 return ICS; 890} 891 892ImplicitConversionSequence 893Sema::TryImplicitConversion(Expr *From, QualType ToType, 894 bool SuppressUserConversions, 895 bool AllowExplicit, 896 bool InOverloadResolution, 897 bool CStyle, 898 bool AllowObjCWritebackConversion) { 899 return clang::TryImplicitConversion(*this, From, ToType, 900 SuppressUserConversions, AllowExplicit, 901 InOverloadResolution, CStyle, 902 AllowObjCWritebackConversion); 903} 904 905/// PerformImplicitConversion - Perform an implicit conversion of the 906/// expression From to the type ToType. Returns the 907/// converted expression. Flavor is the kind of conversion we're 908/// performing, used in the error message. If @p AllowExplicit, 909/// explicit user-defined conversions are permitted. 910ExprResult 911Sema::PerformImplicitConversion(Expr *From, QualType ToType, 912 AssignmentAction Action, bool AllowExplicit) { 913 ImplicitConversionSequence ICS; 914 return PerformImplicitConversion(From, ToType, Action, AllowExplicit, ICS); 915} 916 917ExprResult 918Sema::PerformImplicitConversion(Expr *From, QualType ToType, 919 AssignmentAction Action, bool AllowExplicit, 920 ImplicitConversionSequence& ICS) { 921 // Objective-C ARC: Determine whether we will allow the writeback conversion. 922 bool AllowObjCWritebackConversion 923 = getLangOptions().ObjCAutoRefCount && 924 (Action == AA_Passing || Action == AA_Sending); 925 926 927 ICS = clang::TryImplicitConversion(*this, From, ToType, 928 /*SuppressUserConversions=*/false, 929 AllowExplicit, 930 /*InOverloadResolution=*/false, 931 /*CStyle=*/false, 932 AllowObjCWritebackConversion); 933 return PerformImplicitConversion(From, ToType, ICS, Action); 934} 935 936/// \brief Determine whether the conversion from FromType to ToType is a valid 937/// conversion that strips "noreturn" off the nested function type. 938bool Sema::IsNoReturnConversion(QualType FromType, QualType ToType, 939 QualType &ResultTy) { 940 if (Context.hasSameUnqualifiedType(FromType, ToType)) 941 return false; 942 943 // Permit the conversion F(t __attribute__((noreturn))) -> F(t) 944 // where F adds one of the following at most once: 945 // - a pointer 946 // - a member pointer 947 // - a block pointer 948 CanQualType CanTo = Context.getCanonicalType(ToType); 949 CanQualType CanFrom = Context.getCanonicalType(FromType); 950 Type::TypeClass TyClass = CanTo->getTypeClass(); 951 if (TyClass != CanFrom->getTypeClass()) return false; 952 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) { 953 if (TyClass == Type::Pointer) { 954 CanTo = CanTo.getAs<PointerType>()->getPointeeType(); 955 CanFrom = CanFrom.getAs<PointerType>()->getPointeeType(); 956 } else if (TyClass == Type::BlockPointer) { 957 CanTo = CanTo.getAs<BlockPointerType>()->getPointeeType(); 958 CanFrom = CanFrom.getAs<BlockPointerType>()->getPointeeType(); 959 } else if (TyClass == Type::MemberPointer) { 960 CanTo = CanTo.getAs<MemberPointerType>()->getPointeeType(); 961 CanFrom = CanFrom.getAs<MemberPointerType>()->getPointeeType(); 962 } else { 963 return false; 964 } 965 966 TyClass = CanTo->getTypeClass(); 967 if (TyClass != CanFrom->getTypeClass()) return false; 968 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) 969 return false; 970 } 971 972 const FunctionType *FromFn = cast<FunctionType>(CanFrom); 973 FunctionType::ExtInfo EInfo = FromFn->getExtInfo(); 974 if (!EInfo.getNoReturn()) return false; 975 976 FromFn = Context.adjustFunctionType(FromFn, EInfo.withNoReturn(false)); 977 assert(QualType(FromFn, 0).isCanonical()); 978 if (QualType(FromFn, 0) != CanTo) return false; 979 980 ResultTy = ToType; 981 return true; 982} 983 984/// \brief Determine whether the conversion from FromType to ToType is a valid 985/// vector conversion. 986/// 987/// \param ICK Will be set to the vector conversion kind, if this is a vector 988/// conversion. 989static bool IsVectorConversion(ASTContext &Context, QualType FromType, 990 QualType ToType, ImplicitConversionKind &ICK) { 991 // We need at least one of these types to be a vector type to have a vector 992 // conversion. 993 if (!ToType->isVectorType() && !FromType->isVectorType()) 994 return false; 995 996 // Identical types require no conversions. 997 if (Context.hasSameUnqualifiedType(FromType, ToType)) 998 return false; 999 1000 // There are no conversions between extended vector types, only identity. 1001 if (ToType->isExtVectorType()) { 1002 // There are no conversions between extended vector types other than the 1003 // identity conversion. 1004 if (FromType->isExtVectorType()) 1005 return false; 1006 1007 // Vector splat from any arithmetic type to a vector. 1008 if (FromType->isArithmeticType()) { 1009 ICK = ICK_Vector_Splat; 1010 return true; 1011 } 1012 } 1013 1014 // We can perform the conversion between vector types in the following cases: 1015 // 1)vector types are equivalent AltiVec and GCC vector types 1016 // 2)lax vector conversions are permitted and the vector types are of the 1017 // same size 1018 if (ToType->isVectorType() && FromType->isVectorType()) { 1019 if (Context.areCompatibleVectorTypes(FromType, ToType) || 1020 (Context.getLangOptions().LaxVectorConversions && 1021 (Context.getTypeSize(FromType) == Context.getTypeSize(ToType)))) { 1022 ICK = ICK_Vector_Conversion; 1023 return true; 1024 } 1025 } 1026 1027 return false; 1028} 1029 1030/// IsStandardConversion - Determines whether there is a standard 1031/// conversion sequence (C++ [conv], C++ [over.ics.scs]) from the 1032/// expression From to the type ToType. Standard conversion sequences 1033/// only consider non-class types; for conversions that involve class 1034/// types, use TryImplicitConversion. If a conversion exists, SCS will 1035/// contain the standard conversion sequence required to perform this 1036/// conversion and this routine will return true. Otherwise, this 1037/// routine will return false and the value of SCS is unspecified. 1038static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType, 1039 bool InOverloadResolution, 1040 StandardConversionSequence &SCS, 1041 bool CStyle, 1042 bool AllowObjCWritebackConversion) { 1043 QualType FromType = From->getType(); 1044 1045 // Standard conversions (C++ [conv]) 1046 SCS.setAsIdentityConversion(); 1047 SCS.DeprecatedStringLiteralToCharPtr = false; 1048 SCS.IncompatibleObjC = false; 1049 SCS.setFromType(FromType); 1050 SCS.CopyConstructor = 0; 1051 1052 // There are no standard conversions for class types in C++, so 1053 // abort early. When overloading in C, however, we do permit 1054 if (FromType->isRecordType() || ToType->isRecordType()) { 1055 if (S.getLangOptions().CPlusPlus) 1056 return false; 1057 1058 // When we're overloading in C, we allow, as standard conversions, 1059 } 1060 1061 // The first conversion can be an lvalue-to-rvalue conversion, 1062 // array-to-pointer conversion, or function-to-pointer conversion 1063 // (C++ 4p1). 1064 1065 if (FromType == S.Context.OverloadTy) { 1066 DeclAccessPair AccessPair; 1067 if (FunctionDecl *Fn 1068 = S.ResolveAddressOfOverloadedFunction(From, ToType, false, 1069 AccessPair)) { 1070 // We were able to resolve the address of the overloaded function, 1071 // so we can convert to the type of that function. 1072 FromType = Fn->getType(); 1073 1074 // we can sometimes resolve &foo<int> regardless of ToType, so check 1075 // if the type matches (identity) or we are converting to bool 1076 if (!S.Context.hasSameUnqualifiedType( 1077 S.ExtractUnqualifiedFunctionType(ToType), FromType)) { 1078 QualType resultTy; 1079 // if the function type matches except for [[noreturn]], it's ok 1080 if (!S.IsNoReturnConversion(FromType, 1081 S.ExtractUnqualifiedFunctionType(ToType), resultTy)) 1082 // otherwise, only a boolean conversion is standard 1083 if (!ToType->isBooleanType()) 1084 return false; 1085 } 1086 1087 // Check if the "from" expression is taking the address of an overloaded 1088 // function and recompute the FromType accordingly. Take advantage of the 1089 // fact that non-static member functions *must* have such an address-of 1090 // expression. 1091 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn); 1092 if (Method && !Method->isStatic()) { 1093 assert(isa<UnaryOperator>(From->IgnoreParens()) && 1094 "Non-unary operator on non-static member address"); 1095 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() 1096 == UO_AddrOf && 1097 "Non-address-of operator on non-static member address"); 1098 const Type *ClassType 1099 = S.Context.getTypeDeclType(Method->getParent()).getTypePtr(); 1100 FromType = S.Context.getMemberPointerType(FromType, ClassType); 1101 } else if (isa<UnaryOperator>(From->IgnoreParens())) { 1102 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == 1103 UO_AddrOf && 1104 "Non-address-of operator for overloaded function expression"); 1105 FromType = S.Context.getPointerType(FromType); 1106 } 1107 1108 // Check that we've computed the proper type after overload resolution. 1109 assert(S.Context.hasSameType( 1110 FromType, 1111 S.FixOverloadedFunctionReference(From, AccessPair, Fn)->getType())); 1112 } else { 1113 return false; 1114 } 1115 } 1116 // Lvalue-to-rvalue conversion (C++ 4.1): 1117 // An lvalue (3.10) of a non-function, non-array type T can be 1118 // converted to an rvalue. 1119 bool argIsLValue = From->isLValue(); 1120 if (argIsLValue && 1121 !FromType->isFunctionType() && !FromType->isArrayType() && 1122 S.Context.getCanonicalType(FromType) != S.Context.OverloadTy) { 1123 SCS.First = ICK_Lvalue_To_Rvalue; 1124 1125 // If T is a non-class type, the type of the rvalue is the 1126 // cv-unqualified version of T. Otherwise, the type of the rvalue 1127 // is T (C++ 4.1p1). C++ can't get here with class types; in C, we 1128 // just strip the qualifiers because they don't matter. 1129 FromType = FromType.getUnqualifiedType(); 1130 } else if (FromType->isArrayType()) { 1131 // Array-to-pointer conversion (C++ 4.2) 1132 SCS.First = ICK_Array_To_Pointer; 1133 1134 // An lvalue or rvalue of type "array of N T" or "array of unknown 1135 // bound of T" can be converted to an rvalue of type "pointer to 1136 // T" (C++ 4.2p1). 1137 FromType = S.Context.getArrayDecayedType(FromType); 1138 1139 if (S.IsStringLiteralToNonConstPointerConversion(From, ToType)) { 1140 // This conversion is deprecated. (C++ D.4). 1141 SCS.DeprecatedStringLiteralToCharPtr = true; 1142 1143 // For the purpose of ranking in overload resolution 1144 // (13.3.3.1.1), this conversion is considered an 1145 // array-to-pointer conversion followed by a qualification 1146 // conversion (4.4). (C++ 4.2p2) 1147 SCS.Second = ICK_Identity; 1148 SCS.Third = ICK_Qualification; 1149 SCS.QualificationIncludesObjCLifetime = false; 1150 SCS.setAllToTypes(FromType); 1151 return true; 1152 } 1153 } else if (FromType->isFunctionType() && argIsLValue) { 1154 // Function-to-pointer conversion (C++ 4.3). 1155 SCS.First = ICK_Function_To_Pointer; 1156 1157 // An lvalue of function type T can be converted to an rvalue of 1158 // type "pointer to T." The result is a pointer to the 1159 // function. (C++ 4.3p1). 1160 FromType = S.Context.getPointerType(FromType); 1161 } else { 1162 // We don't require any conversions for the first step. 1163 SCS.First = ICK_Identity; 1164 } 1165 SCS.setToType(0, FromType); 1166 1167 // The second conversion can be an integral promotion, floating 1168 // point promotion, integral conversion, floating point conversion, 1169 // floating-integral conversion, pointer conversion, 1170 // pointer-to-member conversion, or boolean conversion (C++ 4p1). 1171 // For overloading in C, this can also be a "compatible-type" 1172 // conversion. 1173 bool IncompatibleObjC = false; 1174 ImplicitConversionKind SecondICK = ICK_Identity; 1175 if (S.Context.hasSameUnqualifiedType(FromType, ToType)) { 1176 // The unqualified versions of the types are the same: there's no 1177 // conversion to do. 1178 SCS.Second = ICK_Identity; 1179 } else if (S.IsIntegralPromotion(From, FromType, ToType)) { 1180 // Integral promotion (C++ 4.5). 1181 SCS.Second = ICK_Integral_Promotion; 1182 FromType = ToType.getUnqualifiedType(); 1183 } else if (S.IsFloatingPointPromotion(FromType, ToType)) { 1184 // Floating point promotion (C++ 4.6). 1185 SCS.Second = ICK_Floating_Promotion; 1186 FromType = ToType.getUnqualifiedType(); 1187 } else if (S.IsComplexPromotion(FromType, ToType)) { 1188 // Complex promotion (Clang extension) 1189 SCS.Second = ICK_Complex_Promotion; 1190 FromType = ToType.getUnqualifiedType(); 1191 } else if (ToType->isBooleanType() && 1192 (FromType->isArithmeticType() || 1193 FromType->isAnyPointerType() || 1194 FromType->isBlockPointerType() || 1195 FromType->isMemberPointerType() || 1196 FromType->isNullPtrType())) { 1197 // Boolean conversions (C++ 4.12). 1198 SCS.Second = ICK_Boolean_Conversion; 1199 FromType = S.Context.BoolTy; 1200 } else if (FromType->isIntegralOrUnscopedEnumerationType() && 1201 ToType->isIntegralType(S.Context)) { 1202 // Integral conversions (C++ 4.7). 1203 SCS.Second = ICK_Integral_Conversion; 1204 FromType = ToType.getUnqualifiedType(); 1205 } else if (FromType->isAnyComplexType() && ToType->isComplexType()) { 1206 // Complex conversions (C99 6.3.1.6) 1207 SCS.Second = ICK_Complex_Conversion; 1208 FromType = ToType.getUnqualifiedType(); 1209 } else if ((FromType->isAnyComplexType() && ToType->isArithmeticType()) || 1210 (ToType->isAnyComplexType() && FromType->isArithmeticType())) { 1211 // Complex-real conversions (C99 6.3.1.7) 1212 SCS.Second = ICK_Complex_Real; 1213 FromType = ToType.getUnqualifiedType(); 1214 } else if (FromType->isRealFloatingType() && ToType->isRealFloatingType()) { 1215 // Floating point conversions (C++ 4.8). 1216 SCS.Second = ICK_Floating_Conversion; 1217 FromType = ToType.getUnqualifiedType(); 1218 } else if ((FromType->isRealFloatingType() && 1219 ToType->isIntegralType(S.Context)) || 1220 (FromType->isIntegralOrUnscopedEnumerationType() && 1221 ToType->isRealFloatingType())) { 1222 // Floating-integral conversions (C++ 4.9). 1223 SCS.Second = ICK_Floating_Integral; 1224 FromType = ToType.getUnqualifiedType(); 1225 } else if (S.IsBlockPointerConversion(FromType, ToType, FromType)) { 1226 SCS.Second = ICK_Block_Pointer_Conversion; 1227 } else if (AllowObjCWritebackConversion && 1228 S.isObjCWritebackConversion(FromType, ToType, FromType)) { 1229 SCS.Second = ICK_Writeback_Conversion; 1230 } else if (S.IsPointerConversion(From, FromType, ToType, InOverloadResolution, 1231 FromType, IncompatibleObjC)) { 1232 // Pointer conversions (C++ 4.10). 1233 SCS.Second = ICK_Pointer_Conversion; 1234 SCS.IncompatibleObjC = IncompatibleObjC; 1235 FromType = FromType.getUnqualifiedType(); 1236 } else if (S.IsMemberPointerConversion(From, FromType, ToType, 1237 InOverloadResolution, FromType)) { 1238 // Pointer to member conversions (4.11). 1239 SCS.Second = ICK_Pointer_Member; 1240 } else if (IsVectorConversion(S.Context, FromType, ToType, SecondICK)) { 1241 SCS.Second = SecondICK; 1242 FromType = ToType.getUnqualifiedType(); 1243 } else if (!S.getLangOptions().CPlusPlus && 1244 S.Context.typesAreCompatible(ToType, FromType)) { 1245 // Compatible conversions (Clang extension for C function overloading) 1246 SCS.Second = ICK_Compatible_Conversion; 1247 FromType = ToType.getUnqualifiedType(); 1248 } else if (S.IsNoReturnConversion(FromType, ToType, FromType)) { 1249 // Treat a conversion that strips "noreturn" as an identity conversion. 1250 SCS.Second = ICK_NoReturn_Adjustment; 1251 } else if (IsTransparentUnionStandardConversion(S, From, ToType, 1252 InOverloadResolution, 1253 SCS, CStyle)) { 1254 SCS.Second = ICK_TransparentUnionConversion; 1255 FromType = ToType; 1256 } else { 1257 // No second conversion required. 1258 SCS.Second = ICK_Identity; 1259 } 1260 SCS.setToType(1, FromType); 1261 1262 QualType CanonFrom; 1263 QualType CanonTo; 1264 // The third conversion can be a qualification conversion (C++ 4p1). 1265 bool ObjCLifetimeConversion; 1266 if (S.IsQualificationConversion(FromType, ToType, CStyle, 1267 ObjCLifetimeConversion)) { 1268 SCS.Third = ICK_Qualification; 1269 SCS.QualificationIncludesObjCLifetime = ObjCLifetimeConversion; 1270 FromType = ToType; 1271 CanonFrom = S.Context.getCanonicalType(FromType); 1272 CanonTo = S.Context.getCanonicalType(ToType); 1273 } else { 1274 // No conversion required 1275 SCS.Third = ICK_Identity; 1276 1277 // C++ [over.best.ics]p6: 1278 // [...] Any difference in top-level cv-qualification is 1279 // subsumed by the initialization itself and does not constitute 1280 // a conversion. [...] 1281 CanonFrom = S.Context.getCanonicalType(FromType); 1282 CanonTo = S.Context.getCanonicalType(ToType); 1283 if (CanonFrom.getLocalUnqualifiedType() 1284 == CanonTo.getLocalUnqualifiedType() && 1285 (CanonFrom.getLocalCVRQualifiers() != CanonTo.getLocalCVRQualifiers() 1286 || CanonFrom.getObjCGCAttr() != CanonTo.getObjCGCAttr() 1287 || CanonFrom.getObjCLifetime() != CanonTo.getObjCLifetime())) { 1288 FromType = ToType; 1289 CanonFrom = CanonTo; 1290 } 1291 } 1292 SCS.setToType(2, FromType); 1293 1294 // If we have not converted the argument type to the parameter type, 1295 // this is a bad conversion sequence. 1296 if (CanonFrom != CanonTo) 1297 return false; 1298 1299 return true; 1300} 1301 1302static bool 1303IsTransparentUnionStandardConversion(Sema &S, Expr* From, 1304 QualType &ToType, 1305 bool InOverloadResolution, 1306 StandardConversionSequence &SCS, 1307 bool CStyle) { 1308 1309 const RecordType *UT = ToType->getAsUnionType(); 1310 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 1311 return false; 1312 // The field to initialize within the transparent union. 1313 RecordDecl *UD = UT->getDecl(); 1314 // It's compatible if the expression matches any of the fields. 1315 for (RecordDecl::field_iterator it = UD->field_begin(), 1316 itend = UD->field_end(); 1317 it != itend; ++it) { 1318 if (IsStandardConversion(S, From, it->getType(), InOverloadResolution, SCS, 1319 CStyle, /*ObjCWritebackConversion=*/false)) { 1320 ToType = it->getType(); 1321 return true; 1322 } 1323 } 1324 return false; 1325} 1326 1327/// IsIntegralPromotion - Determines whether the conversion from the 1328/// expression From (whose potentially-adjusted type is FromType) to 1329/// ToType is an integral promotion (C++ 4.5). If so, returns true and 1330/// sets PromotedType to the promoted type. 1331bool Sema::IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType) { 1332 const BuiltinType *To = ToType->getAs<BuiltinType>(); 1333 // All integers are built-in. 1334 if (!To) { 1335 return false; 1336 } 1337 1338 // An rvalue of type char, signed char, unsigned char, short int, or 1339 // unsigned short int can be converted to an rvalue of type int if 1340 // int can represent all the values of the source type; otherwise, 1341 // the source rvalue can be converted to an rvalue of type unsigned 1342 // int (C++ 4.5p1). 1343 if (FromType->isPromotableIntegerType() && !FromType->isBooleanType() && 1344 !FromType->isEnumeralType()) { 1345 if (// We can promote any signed, promotable integer type to an int 1346 (FromType->isSignedIntegerType() || 1347 // We can promote any unsigned integer type whose size is 1348 // less than int to an int. 1349 (!FromType->isSignedIntegerType() && 1350 Context.getTypeSize(FromType) < Context.getTypeSize(ToType)))) { 1351 return To->getKind() == BuiltinType::Int; 1352 } 1353 1354 return To->getKind() == BuiltinType::UInt; 1355 } 1356 1357 // C++0x [conv.prom]p3: 1358 // A prvalue of an unscoped enumeration type whose underlying type is not 1359 // fixed (7.2) can be converted to an rvalue a prvalue of the first of the 1360 // following types that can represent all the values of the enumeration 1361 // (i.e., the values in the range bmin to bmax as described in 7.2): int, 1362 // unsigned int, long int, unsigned long int, long long int, or unsigned 1363 // long long int. If none of the types in that list can represent all the 1364 // values of the enumeration, an rvalue a prvalue of an unscoped enumeration 1365 // type can be converted to an rvalue a prvalue of the extended integer type 1366 // with lowest integer conversion rank (4.13) greater than the rank of long 1367 // long in which all the values of the enumeration can be represented. If 1368 // there are two such extended types, the signed one is chosen. 1369 if (const EnumType *FromEnumType = FromType->getAs<EnumType>()) { 1370 // C++0x 7.2p9: Note that this implicit enum to int conversion is not 1371 // provided for a scoped enumeration. 1372 if (FromEnumType->getDecl()->isScoped()) 1373 return false; 1374 1375 // We have already pre-calculated the promotion type, so this is trivial. 1376 if (ToType->isIntegerType() && 1377 !RequireCompleteType(From->getLocStart(), FromType, PDiag())) 1378 return Context.hasSameUnqualifiedType(ToType, 1379 FromEnumType->getDecl()->getPromotionType()); 1380 } 1381 1382 // C++0x [conv.prom]p2: 1383 // A prvalue of type char16_t, char32_t, or wchar_t (3.9.1) can be converted 1384 // to an rvalue a prvalue of the first of the following types that can 1385 // represent all the values of its underlying type: int, unsigned int, 1386 // long int, unsigned long int, long long int, or unsigned long long int. 1387 // If none of the types in that list can represent all the values of its 1388 // underlying type, an rvalue a prvalue of type char16_t, char32_t, 1389 // or wchar_t can be converted to an rvalue a prvalue of its underlying 1390 // type. 1391 if (FromType->isAnyCharacterType() && !FromType->isCharType() && 1392 ToType->isIntegerType()) { 1393 // Determine whether the type we're converting from is signed or 1394 // unsigned. 1395 bool FromIsSigned = FromType->isSignedIntegerType(); 1396 uint64_t FromSize = Context.getTypeSize(FromType); 1397 1398 // The types we'll try to promote to, in the appropriate 1399 // order. Try each of these types. 1400 QualType PromoteTypes[6] = { 1401 Context.IntTy, Context.UnsignedIntTy, 1402 Context.LongTy, Context.UnsignedLongTy , 1403 Context.LongLongTy, Context.UnsignedLongLongTy 1404 }; 1405 for (int Idx = 0; Idx < 6; ++Idx) { 1406 uint64_t ToSize = Context.getTypeSize(PromoteTypes[Idx]); 1407 if (FromSize < ToSize || 1408 (FromSize == ToSize && 1409 FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType())) { 1410 // We found the type that we can promote to. If this is the 1411 // type we wanted, we have a promotion. Otherwise, no 1412 // promotion. 1413 return Context.hasSameUnqualifiedType(ToType, PromoteTypes[Idx]); 1414 } 1415 } 1416 } 1417 1418 // An rvalue for an integral bit-field (9.6) can be converted to an 1419 // rvalue of type int if int can represent all the values of the 1420 // bit-field; otherwise, it can be converted to unsigned int if 1421 // unsigned int can represent all the values of the bit-field. If 1422 // the bit-field is larger yet, no integral promotion applies to 1423 // it. If the bit-field has an enumerated type, it is treated as any 1424 // other value of that type for promotion purposes (C++ 4.5p3). 1425 // FIXME: We should delay checking of bit-fields until we actually perform the 1426 // conversion. 1427 using llvm::APSInt; 1428 if (From) 1429 if (FieldDecl *MemberDecl = From->getBitField()) { 1430 APSInt BitWidth; 1431 if (FromType->isIntegralType(Context) && 1432 MemberDecl->getBitWidth()->isIntegerConstantExpr(BitWidth, Context)) { 1433 APSInt ToSize(BitWidth.getBitWidth(), BitWidth.isUnsigned()); 1434 ToSize = Context.getTypeSize(ToType); 1435 1436 // Are we promoting to an int from a bitfield that fits in an int? 1437 if (BitWidth < ToSize || 1438 (FromType->isSignedIntegerType() && BitWidth <= ToSize)) { 1439 return To->getKind() == BuiltinType::Int; 1440 } 1441 1442 // Are we promoting to an unsigned int from an unsigned bitfield 1443 // that fits into an unsigned int? 1444 if (FromType->isUnsignedIntegerType() && BitWidth <= ToSize) { 1445 return To->getKind() == BuiltinType::UInt; 1446 } 1447 1448 return false; 1449 } 1450 } 1451 1452 // An rvalue of type bool can be converted to an rvalue of type int, 1453 // with false becoming zero and true becoming one (C++ 4.5p4). 1454 if (FromType->isBooleanType() && To->getKind() == BuiltinType::Int) { 1455 return true; 1456 } 1457 1458 return false; 1459} 1460 1461/// IsFloatingPointPromotion - Determines whether the conversion from 1462/// FromType to ToType is a floating point promotion (C++ 4.6). If so, 1463/// returns true and sets PromotedType to the promoted type. 1464bool Sema::IsFloatingPointPromotion(QualType FromType, QualType ToType) { 1465 /// An rvalue of type float can be converted to an rvalue of type 1466 /// double. (C++ 4.6p1). 1467 if (const BuiltinType *FromBuiltin = FromType->getAs<BuiltinType>()) 1468 if (const BuiltinType *ToBuiltin = ToType->getAs<BuiltinType>()) { 1469 if (FromBuiltin->getKind() == BuiltinType::Float && 1470 ToBuiltin->getKind() == BuiltinType::Double) 1471 return true; 1472 1473 // C99 6.3.1.5p1: 1474 // When a float is promoted to double or long double, or a 1475 // double is promoted to long double [...]. 1476 if (!getLangOptions().CPlusPlus && 1477 (FromBuiltin->getKind() == BuiltinType::Float || 1478 FromBuiltin->getKind() == BuiltinType::Double) && 1479 (ToBuiltin->getKind() == BuiltinType::LongDouble)) 1480 return true; 1481 } 1482 1483 return false; 1484} 1485 1486/// \brief Determine if a conversion is a complex promotion. 1487/// 1488/// A complex promotion is defined as a complex -> complex conversion 1489/// where the conversion between the underlying real types is a 1490/// floating-point or integral promotion. 1491bool Sema::IsComplexPromotion(QualType FromType, QualType ToType) { 1492 const ComplexType *FromComplex = FromType->getAs<ComplexType>(); 1493 if (!FromComplex) 1494 return false; 1495 1496 const ComplexType *ToComplex = ToType->getAs<ComplexType>(); 1497 if (!ToComplex) 1498 return false; 1499 1500 return IsFloatingPointPromotion(FromComplex->getElementType(), 1501 ToComplex->getElementType()) || 1502 IsIntegralPromotion(0, FromComplex->getElementType(), 1503 ToComplex->getElementType()); 1504} 1505 1506/// BuildSimilarlyQualifiedPointerType - In a pointer conversion from 1507/// the pointer type FromPtr to a pointer to type ToPointee, with the 1508/// same type qualifiers as FromPtr has on its pointee type. ToType, 1509/// if non-empty, will be a pointer to ToType that may or may not have 1510/// the right set of qualifiers on its pointee. 1511/// 1512static QualType 1513BuildSimilarlyQualifiedPointerType(const Type *FromPtr, 1514 QualType ToPointee, QualType ToType, 1515 ASTContext &Context, 1516 bool StripObjCLifetime = false) { 1517 assert((FromPtr->getTypeClass() == Type::Pointer || 1518 FromPtr->getTypeClass() == Type::ObjCObjectPointer) && 1519 "Invalid similarly-qualified pointer type"); 1520 1521 /// Conversions to 'id' subsume cv-qualifier conversions. 1522 if (ToType->isObjCIdType() || ToType->isObjCQualifiedIdType()) 1523 return ToType.getUnqualifiedType(); 1524 1525 QualType CanonFromPointee 1526 = Context.getCanonicalType(FromPtr->getPointeeType()); 1527 QualType CanonToPointee = Context.getCanonicalType(ToPointee); 1528 Qualifiers Quals = CanonFromPointee.getQualifiers(); 1529 1530 if (StripObjCLifetime) 1531 Quals.removeObjCLifetime(); 1532 1533 // Exact qualifier match -> return the pointer type we're converting to. 1534 if (CanonToPointee.getLocalQualifiers() == Quals) { 1535 // ToType is exactly what we need. Return it. 1536 if (!ToType.isNull()) 1537 return ToType.getUnqualifiedType(); 1538 1539 // Build a pointer to ToPointee. It has the right qualifiers 1540 // already. 1541 if (isa<ObjCObjectPointerType>(ToType)) 1542 return Context.getObjCObjectPointerType(ToPointee); 1543 return Context.getPointerType(ToPointee); 1544 } 1545 1546 // Just build a canonical type that has the right qualifiers. 1547 QualType QualifiedCanonToPointee 1548 = Context.getQualifiedType(CanonToPointee.getLocalUnqualifiedType(), Quals); 1549 1550 if (isa<ObjCObjectPointerType>(ToType)) 1551 return Context.getObjCObjectPointerType(QualifiedCanonToPointee); 1552 return Context.getPointerType(QualifiedCanonToPointee); 1553} 1554 1555static bool isNullPointerConstantForConversion(Expr *Expr, 1556 bool InOverloadResolution, 1557 ASTContext &Context) { 1558 // Handle value-dependent integral null pointer constants correctly. 1559 // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#903 1560 if (Expr->isValueDependent() && !Expr->isTypeDependent() && 1561 Expr->getType()->isIntegerType() && !Expr->getType()->isEnumeralType()) 1562 return !InOverloadResolution; 1563 1564 return Expr->isNullPointerConstant(Context, 1565 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 1566 : Expr::NPC_ValueDependentIsNull); 1567} 1568 1569/// IsPointerConversion - Determines whether the conversion of the 1570/// expression From, which has the (possibly adjusted) type FromType, 1571/// can be converted to the type ToType via a pointer conversion (C++ 1572/// 4.10). If so, returns true and places the converted type (that 1573/// might differ from ToType in its cv-qualifiers at some level) into 1574/// ConvertedType. 1575/// 1576/// This routine also supports conversions to and from block pointers 1577/// and conversions with Objective-C's 'id', 'id<protocols...>', and 1578/// pointers to interfaces. FIXME: Once we've determined the 1579/// appropriate overloading rules for Objective-C, we may want to 1580/// split the Objective-C checks into a different routine; however, 1581/// GCC seems to consider all of these conversions to be pointer 1582/// conversions, so for now they live here. IncompatibleObjC will be 1583/// set if the conversion is an allowed Objective-C conversion that 1584/// should result in a warning. 1585bool Sema::IsPointerConversion(Expr *From, QualType FromType, QualType ToType, 1586 bool InOverloadResolution, 1587 QualType& ConvertedType, 1588 bool &IncompatibleObjC) { 1589 IncompatibleObjC = false; 1590 if (isObjCPointerConversion(FromType, ToType, ConvertedType, 1591 IncompatibleObjC)) 1592 return true; 1593 1594 // Conversion from a null pointer constant to any Objective-C pointer type. 1595 if (ToType->isObjCObjectPointerType() && 1596 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1597 ConvertedType = ToType; 1598 return true; 1599 } 1600 1601 // Blocks: Block pointers can be converted to void*. 1602 if (FromType->isBlockPointerType() && ToType->isPointerType() && 1603 ToType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 1604 ConvertedType = ToType; 1605 return true; 1606 } 1607 // Blocks: A null pointer constant can be converted to a block 1608 // pointer type. 1609 if (ToType->isBlockPointerType() && 1610 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1611 ConvertedType = ToType; 1612 return true; 1613 } 1614 1615 // If the left-hand-side is nullptr_t, the right side can be a null 1616 // pointer constant. 1617 if (ToType->isNullPtrType() && 1618 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1619 ConvertedType = ToType; 1620 return true; 1621 } 1622 1623 const PointerType* ToTypePtr = ToType->getAs<PointerType>(); 1624 if (!ToTypePtr) 1625 return false; 1626 1627 // A null pointer constant can be converted to a pointer type (C++ 4.10p1). 1628 if (isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1629 ConvertedType = ToType; 1630 return true; 1631 } 1632 1633 // Beyond this point, both types need to be pointers 1634 // , including objective-c pointers. 1635 QualType ToPointeeType = ToTypePtr->getPointeeType(); 1636 if (FromType->isObjCObjectPointerType() && ToPointeeType->isVoidType() && 1637 !getLangOptions().ObjCAutoRefCount) { 1638 ConvertedType = BuildSimilarlyQualifiedPointerType( 1639 FromType->getAs<ObjCObjectPointerType>(), 1640 ToPointeeType, 1641 ToType, Context); 1642 return true; 1643 } 1644 const PointerType *FromTypePtr = FromType->getAs<PointerType>(); 1645 if (!FromTypePtr) 1646 return false; 1647 1648 QualType FromPointeeType = FromTypePtr->getPointeeType(); 1649 1650 // If the unqualified pointee types are the same, this can't be a 1651 // pointer conversion, so don't do all of the work below. 1652 if (Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) 1653 return false; 1654 1655 // An rvalue of type "pointer to cv T," where T is an object type, 1656 // can be converted to an rvalue of type "pointer to cv void" (C++ 1657 // 4.10p2). 1658 if (FromPointeeType->isIncompleteOrObjectType() && 1659 ToPointeeType->isVoidType()) { 1660 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1661 ToPointeeType, 1662 ToType, Context, 1663 /*StripObjCLifetime=*/true); 1664 return true; 1665 } 1666 1667 // MSVC allows implicit function to void* type conversion. 1668 if (getLangOptions().Microsoft && FromPointeeType->isFunctionType() && 1669 ToPointeeType->isVoidType()) { 1670 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1671 ToPointeeType, 1672 ToType, Context); 1673 return true; 1674 } 1675 1676 // When we're overloading in C, we allow a special kind of pointer 1677 // conversion for compatible-but-not-identical pointee types. 1678 if (!getLangOptions().CPlusPlus && 1679 Context.typesAreCompatible(FromPointeeType, ToPointeeType)) { 1680 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1681 ToPointeeType, 1682 ToType, Context); 1683 return true; 1684 } 1685 1686 // C++ [conv.ptr]p3: 1687 // 1688 // An rvalue of type "pointer to cv D," where D is a class type, 1689 // can be converted to an rvalue of type "pointer to cv B," where 1690 // B is a base class (clause 10) of D. If B is an inaccessible 1691 // (clause 11) or ambiguous (10.2) base class of D, a program that 1692 // necessitates this conversion is ill-formed. The result of the 1693 // conversion is a pointer to the base class sub-object of the 1694 // derived class object. The null pointer value is converted to 1695 // the null pointer value of the destination type. 1696 // 1697 // Note that we do not check for ambiguity or inaccessibility 1698 // here. That is handled by CheckPointerConversion. 1699 if (getLangOptions().CPlusPlus && 1700 FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 1701 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType) && 1702 !RequireCompleteType(From->getLocStart(), FromPointeeType, PDiag()) && 1703 IsDerivedFrom(FromPointeeType, ToPointeeType)) { 1704 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1705 ToPointeeType, 1706 ToType, Context); 1707 return true; 1708 } 1709 1710 if (FromPointeeType->isVectorType() && ToPointeeType->isVectorType() && 1711 Context.areCompatibleVectorTypes(FromPointeeType, ToPointeeType)) { 1712 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1713 ToPointeeType, 1714 ToType, Context); 1715 return true; 1716 } 1717 1718 return false; 1719} 1720 1721/// \brief Adopt the given qualifiers for the given type. 1722static QualType AdoptQualifiers(ASTContext &Context, QualType T, Qualifiers Qs){ 1723 Qualifiers TQs = T.getQualifiers(); 1724 1725 // Check whether qualifiers already match. 1726 if (TQs == Qs) 1727 return T; 1728 1729 if (Qs.compatiblyIncludes(TQs)) 1730 return Context.getQualifiedType(T, Qs); 1731 1732 return Context.getQualifiedType(T.getUnqualifiedType(), Qs); 1733} 1734 1735/// isObjCPointerConversion - Determines whether this is an 1736/// Objective-C pointer conversion. Subroutine of IsPointerConversion, 1737/// with the same arguments and return values. 1738bool Sema::isObjCPointerConversion(QualType FromType, QualType ToType, 1739 QualType& ConvertedType, 1740 bool &IncompatibleObjC) { 1741 if (!getLangOptions().ObjC1) 1742 return false; 1743 1744 // The set of qualifiers on the type we're converting from. 1745 Qualifiers FromQualifiers = FromType.getQualifiers(); 1746 1747 // First, we handle all conversions on ObjC object pointer types. 1748 const ObjCObjectPointerType* ToObjCPtr = 1749 ToType->getAs<ObjCObjectPointerType>(); 1750 const ObjCObjectPointerType *FromObjCPtr = 1751 FromType->getAs<ObjCObjectPointerType>(); 1752 1753 if (ToObjCPtr && FromObjCPtr) { 1754 // If the pointee types are the same (ignoring qualifications), 1755 // then this is not a pointer conversion. 1756 if (Context.hasSameUnqualifiedType(ToObjCPtr->getPointeeType(), 1757 FromObjCPtr->getPointeeType())) 1758 return false; 1759 1760 // Check for compatible 1761 // Objective C++: We're able to convert between "id" or "Class" and a 1762 // pointer to any interface (in both directions). 1763 if (ToObjCPtr->isObjCBuiltinType() && FromObjCPtr->isObjCBuiltinType()) { 1764 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1765 return true; 1766 } 1767 // Conversions with Objective-C's id<...>. 1768 if ((FromObjCPtr->isObjCQualifiedIdType() || 1769 ToObjCPtr->isObjCQualifiedIdType()) && 1770 Context.ObjCQualifiedIdTypesAreCompatible(ToType, FromType, 1771 /*compare=*/false)) { 1772 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1773 return true; 1774 } 1775 // Objective C++: We're able to convert from a pointer to an 1776 // interface to a pointer to a different interface. 1777 if (Context.canAssignObjCInterfaces(ToObjCPtr, FromObjCPtr)) { 1778 const ObjCInterfaceType* LHS = ToObjCPtr->getInterfaceType(); 1779 const ObjCInterfaceType* RHS = FromObjCPtr->getInterfaceType(); 1780 if (getLangOptions().CPlusPlus && LHS && RHS && 1781 !ToObjCPtr->getPointeeType().isAtLeastAsQualifiedAs( 1782 FromObjCPtr->getPointeeType())) 1783 return false; 1784 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 1785 ToObjCPtr->getPointeeType(), 1786 ToType, Context); 1787 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1788 return true; 1789 } 1790 1791 if (Context.canAssignObjCInterfaces(FromObjCPtr, ToObjCPtr)) { 1792 // Okay: this is some kind of implicit downcast of Objective-C 1793 // interfaces, which is permitted. However, we're going to 1794 // complain about it. 1795 IncompatibleObjC = true; 1796 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 1797 ToObjCPtr->getPointeeType(), 1798 ToType, Context); 1799 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1800 return true; 1801 } 1802 } 1803 // Beyond this point, both types need to be C pointers or block pointers. 1804 QualType ToPointeeType; 1805 if (const PointerType *ToCPtr = ToType->getAs<PointerType>()) 1806 ToPointeeType = ToCPtr->getPointeeType(); 1807 else if (const BlockPointerType *ToBlockPtr = 1808 ToType->getAs<BlockPointerType>()) { 1809 // Objective C++: We're able to convert from a pointer to any object 1810 // to a block pointer type. 1811 if (FromObjCPtr && FromObjCPtr->isObjCBuiltinType()) { 1812 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1813 return true; 1814 } 1815 ToPointeeType = ToBlockPtr->getPointeeType(); 1816 } 1817 else if (FromType->getAs<BlockPointerType>() && 1818 ToObjCPtr && ToObjCPtr->isObjCBuiltinType()) { 1819 // Objective C++: We're able to convert from a block pointer type to a 1820 // pointer to any object. 1821 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1822 return true; 1823 } 1824 else 1825 return false; 1826 1827 QualType FromPointeeType; 1828 if (const PointerType *FromCPtr = FromType->getAs<PointerType>()) 1829 FromPointeeType = FromCPtr->getPointeeType(); 1830 else if (const BlockPointerType *FromBlockPtr = 1831 FromType->getAs<BlockPointerType>()) 1832 FromPointeeType = FromBlockPtr->getPointeeType(); 1833 else 1834 return false; 1835 1836 // If we have pointers to pointers, recursively check whether this 1837 // is an Objective-C conversion. 1838 if (FromPointeeType->isPointerType() && ToPointeeType->isPointerType() && 1839 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1840 IncompatibleObjC)) { 1841 // We always complain about this conversion. 1842 IncompatibleObjC = true; 1843 ConvertedType = Context.getPointerType(ConvertedType); 1844 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1845 return true; 1846 } 1847 // Allow conversion of pointee being objective-c pointer to another one; 1848 // as in I* to id. 1849 if (FromPointeeType->getAs<ObjCObjectPointerType>() && 1850 ToPointeeType->getAs<ObjCObjectPointerType>() && 1851 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1852 IncompatibleObjC)) { 1853 1854 ConvertedType = Context.getPointerType(ConvertedType); 1855 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1856 return true; 1857 } 1858 1859 // If we have pointers to functions or blocks, check whether the only 1860 // differences in the argument and result types are in Objective-C 1861 // pointer conversions. If so, we permit the conversion (but 1862 // complain about it). 1863 const FunctionProtoType *FromFunctionType 1864 = FromPointeeType->getAs<FunctionProtoType>(); 1865 const FunctionProtoType *ToFunctionType 1866 = ToPointeeType->getAs<FunctionProtoType>(); 1867 if (FromFunctionType && ToFunctionType) { 1868 // If the function types are exactly the same, this isn't an 1869 // Objective-C pointer conversion. 1870 if (Context.getCanonicalType(FromPointeeType) 1871 == Context.getCanonicalType(ToPointeeType)) 1872 return false; 1873 1874 // Perform the quick checks that will tell us whether these 1875 // function types are obviously different. 1876 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 1877 FromFunctionType->isVariadic() != ToFunctionType->isVariadic() || 1878 FromFunctionType->getTypeQuals() != ToFunctionType->getTypeQuals()) 1879 return false; 1880 1881 bool HasObjCConversion = false; 1882 if (Context.getCanonicalType(FromFunctionType->getResultType()) 1883 == Context.getCanonicalType(ToFunctionType->getResultType())) { 1884 // Okay, the types match exactly. Nothing to do. 1885 } else if (isObjCPointerConversion(FromFunctionType->getResultType(), 1886 ToFunctionType->getResultType(), 1887 ConvertedType, IncompatibleObjC)) { 1888 // Okay, we have an Objective-C pointer conversion. 1889 HasObjCConversion = true; 1890 } else { 1891 // Function types are too different. Abort. 1892 return false; 1893 } 1894 1895 // Check argument types. 1896 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 1897 ArgIdx != NumArgs; ++ArgIdx) { 1898 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 1899 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 1900 if (Context.getCanonicalType(FromArgType) 1901 == Context.getCanonicalType(ToArgType)) { 1902 // Okay, the types match exactly. Nothing to do. 1903 } else if (isObjCPointerConversion(FromArgType, ToArgType, 1904 ConvertedType, IncompatibleObjC)) { 1905 // Okay, we have an Objective-C pointer conversion. 1906 HasObjCConversion = true; 1907 } else { 1908 // Argument types are too different. Abort. 1909 return false; 1910 } 1911 } 1912 1913 if (HasObjCConversion) { 1914 // We had an Objective-C conversion. Allow this pointer 1915 // conversion, but complain about it. 1916 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1917 IncompatibleObjC = true; 1918 return true; 1919 } 1920 } 1921 1922 return false; 1923} 1924 1925/// \brief Determine whether this is an Objective-C writeback conversion, 1926/// used for parameter passing when performing automatic reference counting. 1927/// 1928/// \param FromType The type we're converting form. 1929/// 1930/// \param ToType The type we're converting to. 1931/// 1932/// \param ConvertedType The type that will be produced after applying 1933/// this conversion. 1934bool Sema::isObjCWritebackConversion(QualType FromType, QualType ToType, 1935 QualType &ConvertedType) { 1936 if (!getLangOptions().ObjCAutoRefCount || 1937 Context.hasSameUnqualifiedType(FromType, ToType)) 1938 return false; 1939 1940 // Parameter must be a pointer to __autoreleasing (with no other qualifiers). 1941 QualType ToPointee; 1942 if (const PointerType *ToPointer = ToType->getAs<PointerType>()) 1943 ToPointee = ToPointer->getPointeeType(); 1944 else 1945 return false; 1946 1947 Qualifiers ToQuals = ToPointee.getQualifiers(); 1948 if (!ToPointee->isObjCLifetimeType() || 1949 ToQuals.getObjCLifetime() != Qualifiers::OCL_Autoreleasing || 1950 !ToQuals.withoutObjCGLifetime().empty()) 1951 return false; 1952 1953 // Argument must be a pointer to __strong to __weak. 1954 QualType FromPointee; 1955 if (const PointerType *FromPointer = FromType->getAs<PointerType>()) 1956 FromPointee = FromPointer->getPointeeType(); 1957 else 1958 return false; 1959 1960 Qualifiers FromQuals = FromPointee.getQualifiers(); 1961 if (!FromPointee->isObjCLifetimeType() || 1962 (FromQuals.getObjCLifetime() != Qualifiers::OCL_Strong && 1963 FromQuals.getObjCLifetime() != Qualifiers::OCL_Weak)) 1964 return false; 1965 1966 // Make sure that we have compatible qualifiers. 1967 FromQuals.setObjCLifetime(Qualifiers::OCL_Autoreleasing); 1968 if (!ToQuals.compatiblyIncludes(FromQuals)) 1969 return false; 1970 1971 // Remove qualifiers from the pointee type we're converting from; they 1972 // aren't used in the compatibility check belong, and we'll be adding back 1973 // qualifiers (with __autoreleasing) if the compatibility check succeeds. 1974 FromPointee = FromPointee.getUnqualifiedType(); 1975 1976 // The unqualified form of the pointee types must be compatible. 1977 ToPointee = ToPointee.getUnqualifiedType(); 1978 bool IncompatibleObjC; 1979 if (Context.typesAreCompatible(FromPointee, ToPointee)) 1980 FromPointee = ToPointee; 1981 else if (!isObjCPointerConversion(FromPointee, ToPointee, FromPointee, 1982 IncompatibleObjC)) 1983 return false; 1984 1985 /// \brief Construct the type we're converting to, which is a pointer to 1986 /// __autoreleasing pointee. 1987 FromPointee = Context.getQualifiedType(FromPointee, FromQuals); 1988 ConvertedType = Context.getPointerType(FromPointee); 1989 return true; 1990} 1991 1992bool Sema::IsBlockPointerConversion(QualType FromType, QualType ToType, 1993 QualType& ConvertedType) { 1994 QualType ToPointeeType; 1995 if (const BlockPointerType *ToBlockPtr = 1996 ToType->getAs<BlockPointerType>()) 1997 ToPointeeType = ToBlockPtr->getPointeeType(); 1998 else 1999 return false; 2000 2001 QualType FromPointeeType; 2002 if (const BlockPointerType *FromBlockPtr = 2003 FromType->getAs<BlockPointerType>()) 2004 FromPointeeType = FromBlockPtr->getPointeeType(); 2005 else 2006 return false; 2007 // We have pointer to blocks, check whether the only 2008 // differences in the argument and result types are in Objective-C 2009 // pointer conversions. If so, we permit the conversion. 2010 2011 const FunctionProtoType *FromFunctionType 2012 = FromPointeeType->getAs<FunctionProtoType>(); 2013 const FunctionProtoType *ToFunctionType 2014 = ToPointeeType->getAs<FunctionProtoType>(); 2015 2016 if (!FromFunctionType || !ToFunctionType) 2017 return false; 2018 2019 if (Context.hasSameType(FromPointeeType, ToPointeeType)) 2020 return true; 2021 2022 // Perform the quick checks that will tell us whether these 2023 // function types are obviously different. 2024 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 2025 FromFunctionType->isVariadic() != ToFunctionType->isVariadic()) 2026 return false; 2027 2028 FunctionType::ExtInfo FromEInfo = FromFunctionType->getExtInfo(); 2029 FunctionType::ExtInfo ToEInfo = ToFunctionType->getExtInfo(); 2030 if (FromEInfo != ToEInfo) 2031 return false; 2032 2033 bool IncompatibleObjC = false; 2034 if (Context.hasSameType(FromFunctionType->getResultType(), 2035 ToFunctionType->getResultType())) { 2036 // Okay, the types match exactly. Nothing to do. 2037 } else { 2038 QualType RHS = FromFunctionType->getResultType(); 2039 QualType LHS = ToFunctionType->getResultType(); 2040 if ((!getLangOptions().CPlusPlus || !RHS->isRecordType()) && 2041 !RHS.hasQualifiers() && LHS.hasQualifiers()) 2042 LHS = LHS.getUnqualifiedType(); 2043 2044 if (Context.hasSameType(RHS,LHS)) { 2045 // OK exact match. 2046 } else if (isObjCPointerConversion(RHS, LHS, 2047 ConvertedType, IncompatibleObjC)) { 2048 if (IncompatibleObjC) 2049 return false; 2050 // Okay, we have an Objective-C pointer conversion. 2051 } 2052 else 2053 return false; 2054 } 2055 2056 // Check argument types. 2057 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 2058 ArgIdx != NumArgs; ++ArgIdx) { 2059 IncompatibleObjC = false; 2060 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 2061 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 2062 if (Context.hasSameType(FromArgType, ToArgType)) { 2063 // Okay, the types match exactly. Nothing to do. 2064 } else if (isObjCPointerConversion(ToArgType, FromArgType, 2065 ConvertedType, IncompatibleObjC)) { 2066 if (IncompatibleObjC) 2067 return false; 2068 // Okay, we have an Objective-C pointer conversion. 2069 } else 2070 // Argument types are too different. Abort. 2071 return false; 2072 } 2073 ConvertedType = ToType; 2074 return true; 2075} 2076 2077/// FunctionArgTypesAreEqual - This routine checks two function proto types 2078/// for equlity of their argument types. Caller has already checked that 2079/// they have same number of arguments. This routine assumes that Objective-C 2080/// pointer types which only differ in their protocol qualifiers are equal. 2081bool Sema::FunctionArgTypesAreEqual(const FunctionProtoType *OldType, 2082 const FunctionProtoType *NewType) { 2083 if (!getLangOptions().ObjC1) 2084 return std::equal(OldType->arg_type_begin(), OldType->arg_type_end(), 2085 NewType->arg_type_begin()); 2086 2087 for (FunctionProtoType::arg_type_iterator O = OldType->arg_type_begin(), 2088 N = NewType->arg_type_begin(), 2089 E = OldType->arg_type_end(); O && (O != E); ++O, ++N) { 2090 QualType ToType = (*O); 2091 QualType FromType = (*N); 2092 if (ToType != FromType) { 2093 if (const PointerType *PTTo = ToType->getAs<PointerType>()) { 2094 if (const PointerType *PTFr = FromType->getAs<PointerType>()) 2095 if ((PTTo->getPointeeType()->isObjCQualifiedIdType() && 2096 PTFr->getPointeeType()->isObjCQualifiedIdType()) || 2097 (PTTo->getPointeeType()->isObjCQualifiedClassType() && 2098 PTFr->getPointeeType()->isObjCQualifiedClassType())) 2099 continue; 2100 } 2101 else if (const ObjCObjectPointerType *PTTo = 2102 ToType->getAs<ObjCObjectPointerType>()) { 2103 if (const ObjCObjectPointerType *PTFr = 2104 FromType->getAs<ObjCObjectPointerType>()) 2105 if (PTTo->getInterfaceDecl() == PTFr->getInterfaceDecl()) 2106 continue; 2107 } 2108 return false; 2109 } 2110 } 2111 return true; 2112} 2113 2114/// CheckPointerConversion - Check the pointer conversion from the 2115/// expression From to the type ToType. This routine checks for 2116/// ambiguous or inaccessible derived-to-base pointer 2117/// conversions for which IsPointerConversion has already returned 2118/// true. It returns true and produces a diagnostic if there was an 2119/// error, or returns false otherwise. 2120bool Sema::CheckPointerConversion(Expr *From, QualType ToType, 2121 CastKind &Kind, 2122 CXXCastPath& BasePath, 2123 bool IgnoreBaseAccess) { 2124 QualType FromType = From->getType(); 2125 bool IsCStyleOrFunctionalCast = IgnoreBaseAccess; 2126 2127 Kind = CK_BitCast; 2128 2129 if (!IsCStyleOrFunctionalCast && 2130 Context.hasSameUnqualifiedType(From->getType(), Context.BoolTy) && 2131 From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 2132 DiagRuntimeBehavior(From->getExprLoc(), From, 2133 PDiag(diag::warn_impcast_bool_to_null_pointer) 2134 << ToType << From->getSourceRange()); 2135 2136 if (const PointerType *FromPtrType = FromType->getAs<PointerType>()) 2137 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) { 2138 QualType FromPointeeType = FromPtrType->getPointeeType(), 2139 ToPointeeType = ToPtrType->getPointeeType(); 2140 2141 if (FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 2142 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) { 2143 // We must have a derived-to-base conversion. Check an 2144 // ambiguous or inaccessible conversion. 2145 if (CheckDerivedToBaseConversion(FromPointeeType, ToPointeeType, 2146 From->getExprLoc(), 2147 From->getSourceRange(), &BasePath, 2148 IgnoreBaseAccess)) 2149 return true; 2150 2151 // The conversion was successful. 2152 Kind = CK_DerivedToBase; 2153 } 2154 } 2155 if (const ObjCObjectPointerType *FromPtrType = 2156 FromType->getAs<ObjCObjectPointerType>()) { 2157 if (const ObjCObjectPointerType *ToPtrType = 2158 ToType->getAs<ObjCObjectPointerType>()) { 2159 // Objective-C++ conversions are always okay. 2160 // FIXME: We should have a different class of conversions for the 2161 // Objective-C++ implicit conversions. 2162 if (FromPtrType->isObjCBuiltinType() || ToPtrType->isObjCBuiltinType()) 2163 return false; 2164 } 2165 } 2166 2167 // We shouldn't fall into this case unless it's valid for other 2168 // reasons. 2169 if (From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 2170 Kind = CK_NullToPointer; 2171 2172 return false; 2173} 2174 2175/// IsMemberPointerConversion - Determines whether the conversion of the 2176/// expression From, which has the (possibly adjusted) type FromType, can be 2177/// converted to the type ToType via a member pointer conversion (C++ 4.11). 2178/// If so, returns true and places the converted type (that might differ from 2179/// ToType in its cv-qualifiers at some level) into ConvertedType. 2180bool Sema::IsMemberPointerConversion(Expr *From, QualType FromType, 2181 QualType ToType, 2182 bool InOverloadResolution, 2183 QualType &ConvertedType) { 2184 const MemberPointerType *ToTypePtr = ToType->getAs<MemberPointerType>(); 2185 if (!ToTypePtr) 2186 return false; 2187 2188 // A null pointer constant can be converted to a member pointer (C++ 4.11p1) 2189 if (From->isNullPointerConstant(Context, 2190 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 2191 : Expr::NPC_ValueDependentIsNull)) { 2192 ConvertedType = ToType; 2193 return true; 2194 } 2195 2196 // Otherwise, both types have to be member pointers. 2197 const MemberPointerType *FromTypePtr = FromType->getAs<MemberPointerType>(); 2198 if (!FromTypePtr) 2199 return false; 2200 2201 // A pointer to member of B can be converted to a pointer to member of D, 2202 // where D is derived from B (C++ 4.11p2). 2203 QualType FromClass(FromTypePtr->getClass(), 0); 2204 QualType ToClass(ToTypePtr->getClass(), 0); 2205 2206 if (!Context.hasSameUnqualifiedType(FromClass, ToClass) && 2207 !RequireCompleteType(From->getLocStart(), ToClass, PDiag()) && 2208 IsDerivedFrom(ToClass, FromClass)) { 2209 ConvertedType = Context.getMemberPointerType(FromTypePtr->getPointeeType(), 2210 ToClass.getTypePtr()); 2211 return true; 2212 } 2213 2214 return false; 2215} 2216 2217/// CheckMemberPointerConversion - Check the member pointer conversion from the 2218/// expression From to the type ToType. This routine checks for ambiguous or 2219/// virtual or inaccessible base-to-derived member pointer conversions 2220/// for which IsMemberPointerConversion has already returned true. It returns 2221/// true and produces a diagnostic if there was an error, or returns false 2222/// otherwise. 2223bool Sema::CheckMemberPointerConversion(Expr *From, QualType ToType, 2224 CastKind &Kind, 2225 CXXCastPath &BasePath, 2226 bool IgnoreBaseAccess) { 2227 QualType FromType = From->getType(); 2228 const MemberPointerType *FromPtrType = FromType->getAs<MemberPointerType>(); 2229 if (!FromPtrType) { 2230 // This must be a null pointer to member pointer conversion 2231 assert(From->isNullPointerConstant(Context, 2232 Expr::NPC_ValueDependentIsNull) && 2233 "Expr must be null pointer constant!"); 2234 Kind = CK_NullToMemberPointer; 2235 return false; 2236 } 2237 2238 const MemberPointerType *ToPtrType = ToType->getAs<MemberPointerType>(); 2239 assert(ToPtrType && "No member pointer cast has a target type " 2240 "that is not a member pointer."); 2241 2242 QualType FromClass = QualType(FromPtrType->getClass(), 0); 2243 QualType ToClass = QualType(ToPtrType->getClass(), 0); 2244 2245 // FIXME: What about dependent types? 2246 assert(FromClass->isRecordType() && "Pointer into non-class."); 2247 assert(ToClass->isRecordType() && "Pointer into non-class."); 2248 2249 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 2250 /*DetectVirtual=*/true); 2251 bool DerivationOkay = IsDerivedFrom(ToClass, FromClass, Paths); 2252 assert(DerivationOkay && 2253 "Should not have been called if derivation isn't OK."); 2254 (void)DerivationOkay; 2255 2256 if (Paths.isAmbiguous(Context.getCanonicalType(FromClass). 2257 getUnqualifiedType())) { 2258 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths); 2259 Diag(From->getExprLoc(), diag::err_ambiguous_memptr_conv) 2260 << 0 << FromClass << ToClass << PathDisplayStr << From->getSourceRange(); 2261 return true; 2262 } 2263 2264 if (const RecordType *VBase = Paths.getDetectedVirtual()) { 2265 Diag(From->getExprLoc(), diag::err_memptr_conv_via_virtual) 2266 << FromClass << ToClass << QualType(VBase, 0) 2267 << From->getSourceRange(); 2268 return true; 2269 } 2270 2271 if (!IgnoreBaseAccess) 2272 CheckBaseClassAccess(From->getExprLoc(), FromClass, ToClass, 2273 Paths.front(), 2274 diag::err_downcast_from_inaccessible_base); 2275 2276 // Must be a base to derived member conversion. 2277 BuildBasePathArray(Paths, BasePath); 2278 Kind = CK_BaseToDerivedMemberPointer; 2279 return false; 2280} 2281 2282/// IsQualificationConversion - Determines whether the conversion from 2283/// an rvalue of type FromType to ToType is a qualification conversion 2284/// (C++ 4.4). 2285/// 2286/// \param ObjCLifetimeConversion Output parameter that will be set to indicate 2287/// when the qualification conversion involves a change in the Objective-C 2288/// object lifetime. 2289bool 2290Sema::IsQualificationConversion(QualType FromType, QualType ToType, 2291 bool CStyle, bool &ObjCLifetimeConversion) { 2292 FromType = Context.getCanonicalType(FromType); 2293 ToType = Context.getCanonicalType(ToType); 2294 ObjCLifetimeConversion = false; 2295 2296 // If FromType and ToType are the same type, this is not a 2297 // qualification conversion. 2298 if (FromType.getUnqualifiedType() == ToType.getUnqualifiedType()) 2299 return false; 2300 2301 // (C++ 4.4p4): 2302 // A conversion can add cv-qualifiers at levels other than the first 2303 // in multi-level pointers, subject to the following rules: [...] 2304 bool PreviousToQualsIncludeConst = true; 2305 bool UnwrappedAnyPointer = false; 2306 while (Context.UnwrapSimilarPointerTypes(FromType, ToType)) { 2307 // Within each iteration of the loop, we check the qualifiers to 2308 // determine if this still looks like a qualification 2309 // conversion. Then, if all is well, we unwrap one more level of 2310 // pointers or pointers-to-members and do it all again 2311 // until there are no more pointers or pointers-to-members left to 2312 // unwrap. 2313 UnwrappedAnyPointer = true; 2314 2315 Qualifiers FromQuals = FromType.getQualifiers(); 2316 Qualifiers ToQuals = ToType.getQualifiers(); 2317 2318 // Objective-C ARC: 2319 // Check Objective-C lifetime conversions. 2320 if (FromQuals.getObjCLifetime() != ToQuals.getObjCLifetime() && 2321 UnwrappedAnyPointer) { 2322 if (ToQuals.compatiblyIncludesObjCLifetime(FromQuals)) { 2323 ObjCLifetimeConversion = true; 2324 FromQuals.removeObjCLifetime(); 2325 ToQuals.removeObjCLifetime(); 2326 } else { 2327 // Qualification conversions cannot cast between different 2328 // Objective-C lifetime qualifiers. 2329 return false; 2330 } 2331 } 2332 2333 // Allow addition/removal of GC attributes but not changing GC attributes. 2334 if (FromQuals.getObjCGCAttr() != ToQuals.getObjCGCAttr() && 2335 (!FromQuals.hasObjCGCAttr() || !ToQuals.hasObjCGCAttr())) { 2336 FromQuals.removeObjCGCAttr(); 2337 ToQuals.removeObjCGCAttr(); 2338 } 2339 2340 // -- for every j > 0, if const is in cv 1,j then const is in cv 2341 // 2,j, and similarly for volatile. 2342 if (!CStyle && !ToQuals.compatiblyIncludes(FromQuals)) 2343 return false; 2344 2345 // -- if the cv 1,j and cv 2,j are different, then const is in 2346 // every cv for 0 < k < j. 2347 if (!CStyle && FromQuals.getCVRQualifiers() != ToQuals.getCVRQualifiers() 2348 && !PreviousToQualsIncludeConst) 2349 return false; 2350 2351 // Keep track of whether all prior cv-qualifiers in the "to" type 2352 // include const. 2353 PreviousToQualsIncludeConst 2354 = PreviousToQualsIncludeConst && ToQuals.hasConst(); 2355 } 2356 2357 // We are left with FromType and ToType being the pointee types 2358 // after unwrapping the original FromType and ToType the same number 2359 // of types. If we unwrapped any pointers, and if FromType and 2360 // ToType have the same unqualified type (since we checked 2361 // qualifiers above), then this is a qualification conversion. 2362 return UnwrappedAnyPointer && Context.hasSameUnqualifiedType(FromType,ToType); 2363} 2364 2365/// Determines whether there is a user-defined conversion sequence 2366/// (C++ [over.ics.user]) that converts expression From to the type 2367/// ToType. If such a conversion exists, User will contain the 2368/// user-defined conversion sequence that performs such a conversion 2369/// and this routine will return true. Otherwise, this routine returns 2370/// false and User is unspecified. 2371/// 2372/// \param AllowExplicit true if the conversion should consider C++0x 2373/// "explicit" conversion functions as well as non-explicit conversion 2374/// functions (C++0x [class.conv.fct]p2). 2375static OverloadingResult 2376IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 2377 UserDefinedConversionSequence& User, 2378 OverloadCandidateSet& CandidateSet, 2379 bool AllowExplicit) { 2380 // Whether we will only visit constructors. 2381 bool ConstructorsOnly = false; 2382 2383 // If the type we are conversion to is a class type, enumerate its 2384 // constructors. 2385 if (const RecordType *ToRecordType = ToType->getAs<RecordType>()) { 2386 // C++ [over.match.ctor]p1: 2387 // When objects of class type are direct-initialized (8.5), or 2388 // copy-initialized from an expression of the same or a 2389 // derived class type (8.5), overload resolution selects the 2390 // constructor. [...] For copy-initialization, the candidate 2391 // functions are all the converting constructors (12.3.1) of 2392 // that class. The argument list is the expression-list within 2393 // the parentheses of the initializer. 2394 if (S.Context.hasSameUnqualifiedType(ToType, From->getType()) || 2395 (From->getType()->getAs<RecordType>() && 2396 S.IsDerivedFrom(From->getType(), ToType))) 2397 ConstructorsOnly = true; 2398 2399 S.RequireCompleteType(From->getLocStart(), ToType, S.PDiag()); 2400 // RequireCompleteType may have returned true due to some invalid decl 2401 // during template instantiation, but ToType may be complete enough now 2402 // to try to recover. 2403 if (ToType->isIncompleteType()) { 2404 // We're not going to find any constructors. 2405 } else if (CXXRecordDecl *ToRecordDecl 2406 = dyn_cast<CXXRecordDecl>(ToRecordType->getDecl())) { 2407 DeclContext::lookup_iterator Con, ConEnd; 2408 for (llvm::tie(Con, ConEnd) = S.LookupConstructors(ToRecordDecl); 2409 Con != ConEnd; ++Con) { 2410 NamedDecl *D = *Con; 2411 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2412 2413 // Find the constructor (which may be a template). 2414 CXXConstructorDecl *Constructor = 0; 2415 FunctionTemplateDecl *ConstructorTmpl 2416 = dyn_cast<FunctionTemplateDecl>(D); 2417 if (ConstructorTmpl) 2418 Constructor 2419 = cast<CXXConstructorDecl>(ConstructorTmpl->getTemplatedDecl()); 2420 else 2421 Constructor = cast<CXXConstructorDecl>(D); 2422 2423 if (!Constructor->isInvalidDecl() && 2424 Constructor->isConvertingConstructor(AllowExplicit)) { 2425 if (ConstructorTmpl) 2426 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2427 /*ExplicitArgs*/ 0, 2428 &From, 1, CandidateSet, 2429 /*SuppressUserConversions=*/ 2430 !ConstructorsOnly); 2431 else 2432 // Allow one user-defined conversion when user specifies a 2433 // From->ToType conversion via an static cast (c-style, etc). 2434 S.AddOverloadCandidate(Constructor, FoundDecl, 2435 &From, 1, CandidateSet, 2436 /*SuppressUserConversions=*/ 2437 !ConstructorsOnly); 2438 } 2439 } 2440 } 2441 } 2442 2443 // Enumerate conversion functions, if we're allowed to. 2444 if (ConstructorsOnly) { 2445 } else if (S.RequireCompleteType(From->getLocStart(), From->getType(), 2446 S.PDiag(0) << From->getSourceRange())) { 2447 // No conversion functions from incomplete types. 2448 } else if (const RecordType *FromRecordType 2449 = From->getType()->getAs<RecordType>()) { 2450 if (CXXRecordDecl *FromRecordDecl 2451 = dyn_cast<CXXRecordDecl>(FromRecordType->getDecl())) { 2452 // Add all of the conversion functions as candidates. 2453 const UnresolvedSetImpl *Conversions 2454 = FromRecordDecl->getVisibleConversionFunctions(); 2455 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 2456 E = Conversions->end(); I != E; ++I) { 2457 DeclAccessPair FoundDecl = I.getPair(); 2458 NamedDecl *D = FoundDecl.getDecl(); 2459 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 2460 if (isa<UsingShadowDecl>(D)) 2461 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2462 2463 CXXConversionDecl *Conv; 2464 FunctionTemplateDecl *ConvTemplate; 2465 if ((ConvTemplate = dyn_cast<FunctionTemplateDecl>(D))) 2466 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 2467 else 2468 Conv = cast<CXXConversionDecl>(D); 2469 2470 if (AllowExplicit || !Conv->isExplicit()) { 2471 if (ConvTemplate) 2472 S.AddTemplateConversionCandidate(ConvTemplate, FoundDecl, 2473 ActingContext, From, ToType, 2474 CandidateSet); 2475 else 2476 S.AddConversionCandidate(Conv, FoundDecl, ActingContext, 2477 From, ToType, CandidateSet); 2478 } 2479 } 2480 } 2481 } 2482 2483 OverloadCandidateSet::iterator Best; 2484 switch (CandidateSet.BestViableFunction(S, From->getLocStart(), Best, true)) { 2485 case OR_Success: 2486 // Record the standard conversion we used and the conversion function. 2487 if (CXXConstructorDecl *Constructor 2488 = dyn_cast<CXXConstructorDecl>(Best->Function)) { 2489 S.MarkDeclarationReferenced(From->getLocStart(), Constructor); 2490 2491 // C++ [over.ics.user]p1: 2492 // If the user-defined conversion is specified by a 2493 // constructor (12.3.1), the initial standard conversion 2494 // sequence converts the source type to the type required by 2495 // the argument of the constructor. 2496 // 2497 QualType ThisType = Constructor->getThisType(S.Context); 2498 if (Best->Conversions[0].isEllipsis()) 2499 User.EllipsisConversion = true; 2500 else { 2501 User.Before = Best->Conversions[0].Standard; 2502 User.EllipsisConversion = false; 2503 } 2504 User.ConversionFunction = Constructor; 2505 User.FoundConversionFunction = Best->FoundDecl.getDecl(); 2506 User.After.setAsIdentityConversion(); 2507 User.After.setFromType(ThisType->getAs<PointerType>()->getPointeeType()); 2508 User.After.setAllToTypes(ToType); 2509 return OR_Success; 2510 } else if (CXXConversionDecl *Conversion 2511 = dyn_cast<CXXConversionDecl>(Best->Function)) { 2512 S.MarkDeclarationReferenced(From->getLocStart(), Conversion); 2513 2514 // C++ [over.ics.user]p1: 2515 // 2516 // [...] If the user-defined conversion is specified by a 2517 // conversion function (12.3.2), the initial standard 2518 // conversion sequence converts the source type to the 2519 // implicit object parameter of the conversion function. 2520 User.Before = Best->Conversions[0].Standard; 2521 User.ConversionFunction = Conversion; 2522 User.FoundConversionFunction = Best->FoundDecl.getDecl(); 2523 User.EllipsisConversion = false; 2524 2525 // C++ [over.ics.user]p2: 2526 // The second standard conversion sequence converts the 2527 // result of the user-defined conversion to the target type 2528 // for the sequence. Since an implicit conversion sequence 2529 // is an initialization, the special rules for 2530 // initialization by user-defined conversion apply when 2531 // selecting the best user-defined conversion for a 2532 // user-defined conversion sequence (see 13.3.3 and 2533 // 13.3.3.1). 2534 User.After = Best->FinalConversion; 2535 return OR_Success; 2536 } else { 2537 llvm_unreachable("Not a constructor or conversion function?"); 2538 return OR_No_Viable_Function; 2539 } 2540 2541 case OR_No_Viable_Function: 2542 return OR_No_Viable_Function; 2543 case OR_Deleted: 2544 // No conversion here! We're done. 2545 return OR_Deleted; 2546 2547 case OR_Ambiguous: 2548 return OR_Ambiguous; 2549 } 2550 2551 return OR_No_Viable_Function; 2552} 2553 2554bool 2555Sema::DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType) { 2556 ImplicitConversionSequence ICS; 2557 OverloadCandidateSet CandidateSet(From->getExprLoc()); 2558 OverloadingResult OvResult = 2559 IsUserDefinedConversion(*this, From, ToType, ICS.UserDefined, 2560 CandidateSet, false); 2561 if (OvResult == OR_Ambiguous) 2562 Diag(From->getSourceRange().getBegin(), 2563 diag::err_typecheck_ambiguous_condition) 2564 << From->getType() << ToType << From->getSourceRange(); 2565 else if (OvResult == OR_No_Viable_Function && !CandidateSet.empty()) 2566 Diag(From->getSourceRange().getBegin(), 2567 diag::err_typecheck_nonviable_condition) 2568 << From->getType() << ToType << From->getSourceRange(); 2569 else 2570 return false; 2571 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &From, 1); 2572 return true; 2573} 2574 2575/// CompareImplicitConversionSequences - Compare two implicit 2576/// conversion sequences to determine whether one is better than the 2577/// other or if they are indistinguishable (C++ 13.3.3.2). 2578static ImplicitConversionSequence::CompareKind 2579CompareImplicitConversionSequences(Sema &S, 2580 const ImplicitConversionSequence& ICS1, 2581 const ImplicitConversionSequence& ICS2) 2582{ 2583 // (C++ 13.3.3.2p2): When comparing the basic forms of implicit 2584 // conversion sequences (as defined in 13.3.3.1) 2585 // -- a standard conversion sequence (13.3.3.1.1) is a better 2586 // conversion sequence than a user-defined conversion sequence or 2587 // an ellipsis conversion sequence, and 2588 // -- a user-defined conversion sequence (13.3.3.1.2) is a better 2589 // conversion sequence than an ellipsis conversion sequence 2590 // (13.3.3.1.3). 2591 // 2592 // C++0x [over.best.ics]p10: 2593 // For the purpose of ranking implicit conversion sequences as 2594 // described in 13.3.3.2, the ambiguous conversion sequence is 2595 // treated as a user-defined sequence that is indistinguishable 2596 // from any other user-defined conversion sequence. 2597 if (ICS1.getKindRank() < ICS2.getKindRank()) 2598 return ImplicitConversionSequence::Better; 2599 else if (ICS2.getKindRank() < ICS1.getKindRank()) 2600 return ImplicitConversionSequence::Worse; 2601 2602 // The following checks require both conversion sequences to be of 2603 // the same kind. 2604 if (ICS1.getKind() != ICS2.getKind()) 2605 return ImplicitConversionSequence::Indistinguishable; 2606 2607 // Two implicit conversion sequences of the same form are 2608 // indistinguishable conversion sequences unless one of the 2609 // following rules apply: (C++ 13.3.3.2p3): 2610 if (ICS1.isStandard()) 2611 return CompareStandardConversionSequences(S, ICS1.Standard, ICS2.Standard); 2612 else if (ICS1.isUserDefined()) { 2613 // User-defined conversion sequence U1 is a better conversion 2614 // sequence than another user-defined conversion sequence U2 if 2615 // they contain the same user-defined conversion function or 2616 // constructor and if the second standard conversion sequence of 2617 // U1 is better than the second standard conversion sequence of 2618 // U2 (C++ 13.3.3.2p3). 2619 if (ICS1.UserDefined.ConversionFunction == 2620 ICS2.UserDefined.ConversionFunction) 2621 return CompareStandardConversionSequences(S, 2622 ICS1.UserDefined.After, 2623 ICS2.UserDefined.After); 2624 } 2625 2626 return ImplicitConversionSequence::Indistinguishable; 2627} 2628 2629static bool hasSimilarType(ASTContext &Context, QualType T1, QualType T2) { 2630 while (Context.UnwrapSimilarPointerTypes(T1, T2)) { 2631 Qualifiers Quals; 2632 T1 = Context.getUnqualifiedArrayType(T1, Quals); 2633 T2 = Context.getUnqualifiedArrayType(T2, Quals); 2634 } 2635 2636 return Context.hasSameUnqualifiedType(T1, T2); 2637} 2638 2639// Per 13.3.3.2p3, compare the given standard conversion sequences to 2640// determine if one is a proper subset of the other. 2641static ImplicitConversionSequence::CompareKind 2642compareStandardConversionSubsets(ASTContext &Context, 2643 const StandardConversionSequence& SCS1, 2644 const StandardConversionSequence& SCS2) { 2645 ImplicitConversionSequence::CompareKind Result 2646 = ImplicitConversionSequence::Indistinguishable; 2647 2648 // the identity conversion sequence is considered to be a subsequence of 2649 // any non-identity conversion sequence 2650 if (SCS1.isIdentityConversion() && !SCS2.isIdentityConversion()) 2651 return ImplicitConversionSequence::Better; 2652 else if (!SCS1.isIdentityConversion() && SCS2.isIdentityConversion()) 2653 return ImplicitConversionSequence::Worse; 2654 2655 if (SCS1.Second != SCS2.Second) { 2656 if (SCS1.Second == ICK_Identity) 2657 Result = ImplicitConversionSequence::Better; 2658 else if (SCS2.Second == ICK_Identity) 2659 Result = ImplicitConversionSequence::Worse; 2660 else 2661 return ImplicitConversionSequence::Indistinguishable; 2662 } else if (!hasSimilarType(Context, SCS1.getToType(1), SCS2.getToType(1))) 2663 return ImplicitConversionSequence::Indistinguishable; 2664 2665 if (SCS1.Third == SCS2.Third) { 2666 return Context.hasSameType(SCS1.getToType(2), SCS2.getToType(2))? Result 2667 : ImplicitConversionSequence::Indistinguishable; 2668 } 2669 2670 if (SCS1.Third == ICK_Identity) 2671 return Result == ImplicitConversionSequence::Worse 2672 ? ImplicitConversionSequence::Indistinguishable 2673 : ImplicitConversionSequence::Better; 2674 2675 if (SCS2.Third == ICK_Identity) 2676 return Result == ImplicitConversionSequence::Better 2677 ? ImplicitConversionSequence::Indistinguishable 2678 : ImplicitConversionSequence::Worse; 2679 2680 return ImplicitConversionSequence::Indistinguishable; 2681} 2682 2683/// \brief Determine whether one of the given reference bindings is better 2684/// than the other based on what kind of bindings they are. 2685static bool isBetterReferenceBindingKind(const StandardConversionSequence &SCS1, 2686 const StandardConversionSequence &SCS2) { 2687 // C++0x [over.ics.rank]p3b4: 2688 // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an 2689 // implicit object parameter of a non-static member function declared 2690 // without a ref-qualifier, and *either* S1 binds an rvalue reference 2691 // to an rvalue and S2 binds an lvalue reference *or S1 binds an 2692 // lvalue reference to a function lvalue and S2 binds an rvalue 2693 // reference*. 2694 // 2695 // FIXME: Rvalue references. We're going rogue with the above edits, 2696 // because the semantics in the current C++0x working paper (N3225 at the 2697 // time of this writing) break the standard definition of std::forward 2698 // and std::reference_wrapper when dealing with references to functions. 2699 // Proposed wording changes submitted to CWG for consideration. 2700 if (SCS1.BindsImplicitObjectArgumentWithoutRefQualifier || 2701 SCS2.BindsImplicitObjectArgumentWithoutRefQualifier) 2702 return false; 2703 2704 return (!SCS1.IsLvalueReference && SCS1.BindsToRvalue && 2705 SCS2.IsLvalueReference) || 2706 (SCS1.IsLvalueReference && SCS1.BindsToFunctionLvalue && 2707 !SCS2.IsLvalueReference); 2708} 2709 2710/// CompareStandardConversionSequences - Compare two standard 2711/// conversion sequences to determine whether one is better than the 2712/// other or if they are indistinguishable (C++ 13.3.3.2p3). 2713static ImplicitConversionSequence::CompareKind 2714CompareStandardConversionSequences(Sema &S, 2715 const StandardConversionSequence& SCS1, 2716 const StandardConversionSequence& SCS2) 2717{ 2718 // Standard conversion sequence S1 is a better conversion sequence 2719 // than standard conversion sequence S2 if (C++ 13.3.3.2p3): 2720 2721 // -- S1 is a proper subsequence of S2 (comparing the conversion 2722 // sequences in the canonical form defined by 13.3.3.1.1, 2723 // excluding any Lvalue Transformation; the identity conversion 2724 // sequence is considered to be a subsequence of any 2725 // non-identity conversion sequence) or, if not that, 2726 if (ImplicitConversionSequence::CompareKind CK 2727 = compareStandardConversionSubsets(S.Context, SCS1, SCS2)) 2728 return CK; 2729 2730 // -- the rank of S1 is better than the rank of S2 (by the rules 2731 // defined below), or, if not that, 2732 ImplicitConversionRank Rank1 = SCS1.getRank(); 2733 ImplicitConversionRank Rank2 = SCS2.getRank(); 2734 if (Rank1 < Rank2) 2735 return ImplicitConversionSequence::Better; 2736 else if (Rank2 < Rank1) 2737 return ImplicitConversionSequence::Worse; 2738 2739 // (C++ 13.3.3.2p4): Two conversion sequences with the same rank 2740 // are indistinguishable unless one of the following rules 2741 // applies: 2742 2743 // A conversion that is not a conversion of a pointer, or 2744 // pointer to member, to bool is better than another conversion 2745 // that is such a conversion. 2746 if (SCS1.isPointerConversionToBool() != SCS2.isPointerConversionToBool()) 2747 return SCS2.isPointerConversionToBool() 2748 ? ImplicitConversionSequence::Better 2749 : ImplicitConversionSequence::Worse; 2750 2751 // C++ [over.ics.rank]p4b2: 2752 // 2753 // If class B is derived directly or indirectly from class A, 2754 // conversion of B* to A* is better than conversion of B* to 2755 // void*, and conversion of A* to void* is better than conversion 2756 // of B* to void*. 2757 bool SCS1ConvertsToVoid 2758 = SCS1.isPointerConversionToVoidPointer(S.Context); 2759 bool SCS2ConvertsToVoid 2760 = SCS2.isPointerConversionToVoidPointer(S.Context); 2761 if (SCS1ConvertsToVoid != SCS2ConvertsToVoid) { 2762 // Exactly one of the conversion sequences is a conversion to 2763 // a void pointer; it's the worse conversion. 2764 return SCS2ConvertsToVoid ? ImplicitConversionSequence::Better 2765 : ImplicitConversionSequence::Worse; 2766 } else if (!SCS1ConvertsToVoid && !SCS2ConvertsToVoid) { 2767 // Neither conversion sequence converts to a void pointer; compare 2768 // their derived-to-base conversions. 2769 if (ImplicitConversionSequence::CompareKind DerivedCK 2770 = CompareDerivedToBaseConversions(S, SCS1, SCS2)) 2771 return DerivedCK; 2772 } else if (SCS1ConvertsToVoid && SCS2ConvertsToVoid && 2773 !S.Context.hasSameType(SCS1.getFromType(), SCS2.getFromType())) { 2774 // Both conversion sequences are conversions to void 2775 // pointers. Compare the source types to determine if there's an 2776 // inheritance relationship in their sources. 2777 QualType FromType1 = SCS1.getFromType(); 2778 QualType FromType2 = SCS2.getFromType(); 2779 2780 // Adjust the types we're converting from via the array-to-pointer 2781 // conversion, if we need to. 2782 if (SCS1.First == ICK_Array_To_Pointer) 2783 FromType1 = S.Context.getArrayDecayedType(FromType1); 2784 if (SCS2.First == ICK_Array_To_Pointer) 2785 FromType2 = S.Context.getArrayDecayedType(FromType2); 2786 2787 QualType FromPointee1 = FromType1->getPointeeType().getUnqualifiedType(); 2788 QualType FromPointee2 = FromType2->getPointeeType().getUnqualifiedType(); 2789 2790 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 2791 return ImplicitConversionSequence::Better; 2792 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 2793 return ImplicitConversionSequence::Worse; 2794 2795 // Objective-C++: If one interface is more specific than the 2796 // other, it is the better one. 2797 const ObjCObjectPointerType* FromObjCPtr1 2798 = FromType1->getAs<ObjCObjectPointerType>(); 2799 const ObjCObjectPointerType* FromObjCPtr2 2800 = FromType2->getAs<ObjCObjectPointerType>(); 2801 if (FromObjCPtr1 && FromObjCPtr2) { 2802 bool AssignLeft = S.Context.canAssignObjCInterfaces(FromObjCPtr1, 2803 FromObjCPtr2); 2804 bool AssignRight = S.Context.canAssignObjCInterfaces(FromObjCPtr2, 2805 FromObjCPtr1); 2806 if (AssignLeft != AssignRight) { 2807 return AssignLeft? ImplicitConversionSequence::Better 2808 : ImplicitConversionSequence::Worse; 2809 } 2810 } 2811 } 2812 2813 // Compare based on qualification conversions (C++ 13.3.3.2p3, 2814 // bullet 3). 2815 if (ImplicitConversionSequence::CompareKind QualCK 2816 = CompareQualificationConversions(S, SCS1, SCS2)) 2817 return QualCK; 2818 2819 if (SCS1.ReferenceBinding && SCS2.ReferenceBinding) { 2820 // Check for a better reference binding based on the kind of bindings. 2821 if (isBetterReferenceBindingKind(SCS1, SCS2)) 2822 return ImplicitConversionSequence::Better; 2823 else if (isBetterReferenceBindingKind(SCS2, SCS1)) 2824 return ImplicitConversionSequence::Worse; 2825 2826 // C++ [over.ics.rank]p3b4: 2827 // -- S1 and S2 are reference bindings (8.5.3), and the types to 2828 // which the references refer are the same type except for 2829 // top-level cv-qualifiers, and the type to which the reference 2830 // initialized by S2 refers is more cv-qualified than the type 2831 // to which the reference initialized by S1 refers. 2832 QualType T1 = SCS1.getToType(2); 2833 QualType T2 = SCS2.getToType(2); 2834 T1 = S.Context.getCanonicalType(T1); 2835 T2 = S.Context.getCanonicalType(T2); 2836 Qualifiers T1Quals, T2Quals; 2837 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 2838 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 2839 if (UnqualT1 == UnqualT2) { 2840 // Objective-C++ ARC: If the references refer to objects with different 2841 // lifetimes, prefer bindings that don't change lifetime. 2842 if (SCS1.ObjCLifetimeConversionBinding != 2843 SCS2.ObjCLifetimeConversionBinding) { 2844 return SCS1.ObjCLifetimeConversionBinding 2845 ? ImplicitConversionSequence::Worse 2846 : ImplicitConversionSequence::Better; 2847 } 2848 2849 // If the type is an array type, promote the element qualifiers to the 2850 // type for comparison. 2851 if (isa<ArrayType>(T1) && T1Quals) 2852 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 2853 if (isa<ArrayType>(T2) && T2Quals) 2854 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 2855 if (T2.isMoreQualifiedThan(T1)) 2856 return ImplicitConversionSequence::Better; 2857 else if (T1.isMoreQualifiedThan(T2)) 2858 return ImplicitConversionSequence::Worse; 2859 } 2860 } 2861 2862 return ImplicitConversionSequence::Indistinguishable; 2863} 2864 2865/// CompareQualificationConversions - Compares two standard conversion 2866/// sequences to determine whether they can be ranked based on their 2867/// qualification conversions (C++ 13.3.3.2p3 bullet 3). 2868ImplicitConversionSequence::CompareKind 2869CompareQualificationConversions(Sema &S, 2870 const StandardConversionSequence& SCS1, 2871 const StandardConversionSequence& SCS2) { 2872 // C++ 13.3.3.2p3: 2873 // -- S1 and S2 differ only in their qualification conversion and 2874 // yield similar types T1 and T2 (C++ 4.4), respectively, and the 2875 // cv-qualification signature of type T1 is a proper subset of 2876 // the cv-qualification signature of type T2, and S1 is not the 2877 // deprecated string literal array-to-pointer conversion (4.2). 2878 if (SCS1.First != SCS2.First || SCS1.Second != SCS2.Second || 2879 SCS1.Third != SCS2.Third || SCS1.Third != ICK_Qualification) 2880 return ImplicitConversionSequence::Indistinguishable; 2881 2882 // FIXME: the example in the standard doesn't use a qualification 2883 // conversion (!) 2884 QualType T1 = SCS1.getToType(2); 2885 QualType T2 = SCS2.getToType(2); 2886 T1 = S.Context.getCanonicalType(T1); 2887 T2 = S.Context.getCanonicalType(T2); 2888 Qualifiers T1Quals, T2Quals; 2889 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 2890 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 2891 2892 // If the types are the same, we won't learn anything by unwrapped 2893 // them. 2894 if (UnqualT1 == UnqualT2) 2895 return ImplicitConversionSequence::Indistinguishable; 2896 2897 // If the type is an array type, promote the element qualifiers to the type 2898 // for comparison. 2899 if (isa<ArrayType>(T1) && T1Quals) 2900 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 2901 if (isa<ArrayType>(T2) && T2Quals) 2902 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 2903 2904 ImplicitConversionSequence::CompareKind Result 2905 = ImplicitConversionSequence::Indistinguishable; 2906 2907 // Objective-C++ ARC: 2908 // Prefer qualification conversions not involving a change in lifetime 2909 // to qualification conversions that do not change lifetime. 2910 if (SCS1.QualificationIncludesObjCLifetime != 2911 SCS2.QualificationIncludesObjCLifetime) { 2912 Result = SCS1.QualificationIncludesObjCLifetime 2913 ? ImplicitConversionSequence::Worse 2914 : ImplicitConversionSequence::Better; 2915 } 2916 2917 while (S.Context.UnwrapSimilarPointerTypes(T1, T2)) { 2918 // Within each iteration of the loop, we check the qualifiers to 2919 // determine if this still looks like a qualification 2920 // conversion. Then, if all is well, we unwrap one more level of 2921 // pointers or pointers-to-members and do it all again 2922 // until there are no more pointers or pointers-to-members left 2923 // to unwrap. This essentially mimics what 2924 // IsQualificationConversion does, but here we're checking for a 2925 // strict subset of qualifiers. 2926 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 2927 // The qualifiers are the same, so this doesn't tell us anything 2928 // about how the sequences rank. 2929 ; 2930 else if (T2.isMoreQualifiedThan(T1)) { 2931 // T1 has fewer qualifiers, so it could be the better sequence. 2932 if (Result == ImplicitConversionSequence::Worse) 2933 // Neither has qualifiers that are a subset of the other's 2934 // qualifiers. 2935 return ImplicitConversionSequence::Indistinguishable; 2936 2937 Result = ImplicitConversionSequence::Better; 2938 } else if (T1.isMoreQualifiedThan(T2)) { 2939 // T2 has fewer qualifiers, so it could be the better sequence. 2940 if (Result == ImplicitConversionSequence::Better) 2941 // Neither has qualifiers that are a subset of the other's 2942 // qualifiers. 2943 return ImplicitConversionSequence::Indistinguishable; 2944 2945 Result = ImplicitConversionSequence::Worse; 2946 } else { 2947 // Qualifiers are disjoint. 2948 return ImplicitConversionSequence::Indistinguishable; 2949 } 2950 2951 // If the types after this point are equivalent, we're done. 2952 if (S.Context.hasSameUnqualifiedType(T1, T2)) 2953 break; 2954 } 2955 2956 // Check that the winning standard conversion sequence isn't using 2957 // the deprecated string literal array to pointer conversion. 2958 switch (Result) { 2959 case ImplicitConversionSequence::Better: 2960 if (SCS1.DeprecatedStringLiteralToCharPtr) 2961 Result = ImplicitConversionSequence::Indistinguishable; 2962 break; 2963 2964 case ImplicitConversionSequence::Indistinguishable: 2965 break; 2966 2967 case ImplicitConversionSequence::Worse: 2968 if (SCS2.DeprecatedStringLiteralToCharPtr) 2969 Result = ImplicitConversionSequence::Indistinguishable; 2970 break; 2971 } 2972 2973 return Result; 2974} 2975 2976/// CompareDerivedToBaseConversions - Compares two standard conversion 2977/// sequences to determine whether they can be ranked based on their 2978/// various kinds of derived-to-base conversions (C++ 2979/// [over.ics.rank]p4b3). As part of these checks, we also look at 2980/// conversions between Objective-C interface types. 2981ImplicitConversionSequence::CompareKind 2982CompareDerivedToBaseConversions(Sema &S, 2983 const StandardConversionSequence& SCS1, 2984 const StandardConversionSequence& SCS2) { 2985 QualType FromType1 = SCS1.getFromType(); 2986 QualType ToType1 = SCS1.getToType(1); 2987 QualType FromType2 = SCS2.getFromType(); 2988 QualType ToType2 = SCS2.getToType(1); 2989 2990 // Adjust the types we're converting from via the array-to-pointer 2991 // conversion, if we need to. 2992 if (SCS1.First == ICK_Array_To_Pointer) 2993 FromType1 = S.Context.getArrayDecayedType(FromType1); 2994 if (SCS2.First == ICK_Array_To_Pointer) 2995 FromType2 = S.Context.getArrayDecayedType(FromType2); 2996 2997 // Canonicalize all of the types. 2998 FromType1 = S.Context.getCanonicalType(FromType1); 2999 ToType1 = S.Context.getCanonicalType(ToType1); 3000 FromType2 = S.Context.getCanonicalType(FromType2); 3001 ToType2 = S.Context.getCanonicalType(ToType2); 3002 3003 // C++ [over.ics.rank]p4b3: 3004 // 3005 // If class B is derived directly or indirectly from class A and 3006 // class C is derived directly or indirectly from B, 3007 // 3008 // Compare based on pointer conversions. 3009 if (SCS1.Second == ICK_Pointer_Conversion && 3010 SCS2.Second == ICK_Pointer_Conversion && 3011 /*FIXME: Remove if Objective-C id conversions get their own rank*/ 3012 FromType1->isPointerType() && FromType2->isPointerType() && 3013 ToType1->isPointerType() && ToType2->isPointerType()) { 3014 QualType FromPointee1 3015 = FromType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3016 QualType ToPointee1 3017 = ToType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3018 QualType FromPointee2 3019 = FromType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3020 QualType ToPointee2 3021 = ToType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3022 3023 // -- conversion of C* to B* is better than conversion of C* to A*, 3024 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 3025 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 3026 return ImplicitConversionSequence::Better; 3027 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 3028 return ImplicitConversionSequence::Worse; 3029 } 3030 3031 // -- conversion of B* to A* is better than conversion of C* to A*, 3032 if (FromPointee1 != FromPointee2 && ToPointee1 == ToPointee2) { 3033 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 3034 return ImplicitConversionSequence::Better; 3035 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 3036 return ImplicitConversionSequence::Worse; 3037 } 3038 } else if (SCS1.Second == ICK_Pointer_Conversion && 3039 SCS2.Second == ICK_Pointer_Conversion) { 3040 const ObjCObjectPointerType *FromPtr1 3041 = FromType1->getAs<ObjCObjectPointerType>(); 3042 const ObjCObjectPointerType *FromPtr2 3043 = FromType2->getAs<ObjCObjectPointerType>(); 3044 const ObjCObjectPointerType *ToPtr1 3045 = ToType1->getAs<ObjCObjectPointerType>(); 3046 const ObjCObjectPointerType *ToPtr2 3047 = ToType2->getAs<ObjCObjectPointerType>(); 3048 3049 if (FromPtr1 && FromPtr2 && ToPtr1 && ToPtr2) { 3050 // Apply the same conversion ranking rules for Objective-C pointer types 3051 // that we do for C++ pointers to class types. However, we employ the 3052 // Objective-C pseudo-subtyping relationship used for assignment of 3053 // Objective-C pointer types. 3054 bool FromAssignLeft 3055 = S.Context.canAssignObjCInterfaces(FromPtr1, FromPtr2); 3056 bool FromAssignRight 3057 = S.Context.canAssignObjCInterfaces(FromPtr2, FromPtr1); 3058 bool ToAssignLeft 3059 = S.Context.canAssignObjCInterfaces(ToPtr1, ToPtr2); 3060 bool ToAssignRight 3061 = S.Context.canAssignObjCInterfaces(ToPtr2, ToPtr1); 3062 3063 // A conversion to an a non-id object pointer type or qualified 'id' 3064 // type is better than a conversion to 'id'. 3065 if (ToPtr1->isObjCIdType() && 3066 (ToPtr2->isObjCQualifiedIdType() || ToPtr2->getInterfaceDecl())) 3067 return ImplicitConversionSequence::Worse; 3068 if (ToPtr2->isObjCIdType() && 3069 (ToPtr1->isObjCQualifiedIdType() || ToPtr1->getInterfaceDecl())) 3070 return ImplicitConversionSequence::Better; 3071 3072 // A conversion to a non-id object pointer type is better than a 3073 // conversion to a qualified 'id' type 3074 if (ToPtr1->isObjCQualifiedIdType() && ToPtr2->getInterfaceDecl()) 3075 return ImplicitConversionSequence::Worse; 3076 if (ToPtr2->isObjCQualifiedIdType() && ToPtr1->getInterfaceDecl()) 3077 return ImplicitConversionSequence::Better; 3078 3079 // A conversion to an a non-Class object pointer type or qualified 'Class' 3080 // type is better than a conversion to 'Class'. 3081 if (ToPtr1->isObjCClassType() && 3082 (ToPtr2->isObjCQualifiedClassType() || ToPtr2->getInterfaceDecl())) 3083 return ImplicitConversionSequence::Worse; 3084 if (ToPtr2->isObjCClassType() && 3085 (ToPtr1->isObjCQualifiedClassType() || ToPtr1->getInterfaceDecl())) 3086 return ImplicitConversionSequence::Better; 3087 3088 // A conversion to a non-Class object pointer type is better than a 3089 // conversion to a qualified 'Class' type. 3090 if (ToPtr1->isObjCQualifiedClassType() && ToPtr2->getInterfaceDecl()) 3091 return ImplicitConversionSequence::Worse; 3092 if (ToPtr2->isObjCQualifiedClassType() && ToPtr1->getInterfaceDecl()) 3093 return ImplicitConversionSequence::Better; 3094 3095 // -- "conversion of C* to B* is better than conversion of C* to A*," 3096 if (S.Context.hasSameType(FromType1, FromType2) && 3097 !FromPtr1->isObjCIdType() && !FromPtr1->isObjCClassType() && 3098 (ToAssignLeft != ToAssignRight)) 3099 return ToAssignLeft? ImplicitConversionSequence::Worse 3100 : ImplicitConversionSequence::Better; 3101 3102 // -- "conversion of B* to A* is better than conversion of C* to A*," 3103 if (S.Context.hasSameUnqualifiedType(ToType1, ToType2) && 3104 (FromAssignLeft != FromAssignRight)) 3105 return FromAssignLeft? ImplicitConversionSequence::Better 3106 : ImplicitConversionSequence::Worse; 3107 } 3108 } 3109 3110 // Ranking of member-pointer types. 3111 if (SCS1.Second == ICK_Pointer_Member && SCS2.Second == ICK_Pointer_Member && 3112 FromType1->isMemberPointerType() && FromType2->isMemberPointerType() && 3113 ToType1->isMemberPointerType() && ToType2->isMemberPointerType()) { 3114 const MemberPointerType * FromMemPointer1 = 3115 FromType1->getAs<MemberPointerType>(); 3116 const MemberPointerType * ToMemPointer1 = 3117 ToType1->getAs<MemberPointerType>(); 3118 const MemberPointerType * FromMemPointer2 = 3119 FromType2->getAs<MemberPointerType>(); 3120 const MemberPointerType * ToMemPointer2 = 3121 ToType2->getAs<MemberPointerType>(); 3122 const Type *FromPointeeType1 = FromMemPointer1->getClass(); 3123 const Type *ToPointeeType1 = ToMemPointer1->getClass(); 3124 const Type *FromPointeeType2 = FromMemPointer2->getClass(); 3125 const Type *ToPointeeType2 = ToMemPointer2->getClass(); 3126 QualType FromPointee1 = QualType(FromPointeeType1, 0).getUnqualifiedType(); 3127 QualType ToPointee1 = QualType(ToPointeeType1, 0).getUnqualifiedType(); 3128 QualType FromPointee2 = QualType(FromPointeeType2, 0).getUnqualifiedType(); 3129 QualType ToPointee2 = QualType(ToPointeeType2, 0).getUnqualifiedType(); 3130 // conversion of A::* to B::* is better than conversion of A::* to C::*, 3131 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 3132 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 3133 return ImplicitConversionSequence::Worse; 3134 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 3135 return ImplicitConversionSequence::Better; 3136 } 3137 // conversion of B::* to C::* is better than conversion of A::* to C::* 3138 if (ToPointee1 == ToPointee2 && FromPointee1 != FromPointee2) { 3139 if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 3140 return ImplicitConversionSequence::Better; 3141 else if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 3142 return ImplicitConversionSequence::Worse; 3143 } 3144 } 3145 3146 if (SCS1.Second == ICK_Derived_To_Base) { 3147 // -- conversion of C to B is better than conversion of C to A, 3148 // -- binding of an expression of type C to a reference of type 3149 // B& is better than binding an expression of type C to a 3150 // reference of type A&, 3151 if (S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3152 !S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3153 if (S.IsDerivedFrom(ToType1, ToType2)) 3154 return ImplicitConversionSequence::Better; 3155 else if (S.IsDerivedFrom(ToType2, ToType1)) 3156 return ImplicitConversionSequence::Worse; 3157 } 3158 3159 // -- conversion of B to A is better than conversion of C to A. 3160 // -- binding of an expression of type B to a reference of type 3161 // A& is better than binding an expression of type C to a 3162 // reference of type A&, 3163 if (!S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3164 S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3165 if (S.IsDerivedFrom(FromType2, FromType1)) 3166 return ImplicitConversionSequence::Better; 3167 else if (S.IsDerivedFrom(FromType1, FromType2)) 3168 return ImplicitConversionSequence::Worse; 3169 } 3170 } 3171 3172 return ImplicitConversionSequence::Indistinguishable; 3173} 3174 3175/// CompareReferenceRelationship - Compare the two types T1 and T2 to 3176/// determine whether they are reference-related, 3177/// reference-compatible, reference-compatible with added 3178/// qualification, or incompatible, for use in C++ initialization by 3179/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 3180/// type, and the first type (T1) is the pointee type of the reference 3181/// type being initialized. 3182Sema::ReferenceCompareResult 3183Sema::CompareReferenceRelationship(SourceLocation Loc, 3184 QualType OrigT1, QualType OrigT2, 3185 bool &DerivedToBase, 3186 bool &ObjCConversion, 3187 bool &ObjCLifetimeConversion) { 3188 assert(!OrigT1->isReferenceType() && 3189 "T1 must be the pointee type of the reference type"); 3190 assert(!OrigT2->isReferenceType() && "T2 cannot be a reference type"); 3191 3192 QualType T1 = Context.getCanonicalType(OrigT1); 3193 QualType T2 = Context.getCanonicalType(OrigT2); 3194 Qualifiers T1Quals, T2Quals; 3195 QualType UnqualT1 = Context.getUnqualifiedArrayType(T1, T1Quals); 3196 QualType UnqualT2 = Context.getUnqualifiedArrayType(T2, T2Quals); 3197 3198 // C++ [dcl.init.ref]p4: 3199 // Given types "cv1 T1" and "cv2 T2," "cv1 T1" is 3200 // reference-related to "cv2 T2" if T1 is the same type as T2, or 3201 // T1 is a base class of T2. 3202 DerivedToBase = false; 3203 ObjCConversion = false; 3204 ObjCLifetimeConversion = false; 3205 if (UnqualT1 == UnqualT2) { 3206 // Nothing to do. 3207 } else if (!RequireCompleteType(Loc, OrigT2, PDiag()) && 3208 IsDerivedFrom(UnqualT2, UnqualT1)) 3209 DerivedToBase = true; 3210 else if (UnqualT1->isObjCObjectOrInterfaceType() && 3211 UnqualT2->isObjCObjectOrInterfaceType() && 3212 Context.canBindObjCObjectType(UnqualT1, UnqualT2)) 3213 ObjCConversion = true; 3214 else 3215 return Ref_Incompatible; 3216 3217 // At this point, we know that T1 and T2 are reference-related (at 3218 // least). 3219 3220 // If the type is an array type, promote the element qualifiers to the type 3221 // for comparison. 3222 if (isa<ArrayType>(T1) && T1Quals) 3223 T1 = Context.getQualifiedType(UnqualT1, T1Quals); 3224 if (isa<ArrayType>(T2) && T2Quals) 3225 T2 = Context.getQualifiedType(UnqualT2, T2Quals); 3226 3227 // C++ [dcl.init.ref]p4: 3228 // "cv1 T1" is reference-compatible with "cv2 T2" if T1 is 3229 // reference-related to T2 and cv1 is the same cv-qualification 3230 // as, or greater cv-qualification than, cv2. For purposes of 3231 // overload resolution, cases for which cv1 is greater 3232 // cv-qualification than cv2 are identified as 3233 // reference-compatible with added qualification (see 13.3.3.2). 3234 // 3235 // Note that we also require equivalence of Objective-C GC and address-space 3236 // qualifiers when performing these computations, so that e.g., an int in 3237 // address space 1 is not reference-compatible with an int in address 3238 // space 2. 3239 if (T1Quals.getObjCLifetime() != T2Quals.getObjCLifetime() && 3240 T1Quals.compatiblyIncludesObjCLifetime(T2Quals)) { 3241 T1Quals.removeObjCLifetime(); 3242 T2Quals.removeObjCLifetime(); 3243 ObjCLifetimeConversion = true; 3244 } 3245 3246 if (T1Quals == T2Quals) 3247 return Ref_Compatible; 3248 else if (T1Quals.compatiblyIncludes(T2Quals)) 3249 return Ref_Compatible_With_Added_Qualification; 3250 else 3251 return Ref_Related; 3252} 3253 3254/// \brief Look for a user-defined conversion to an value reference-compatible 3255/// with DeclType. Return true if something definite is found. 3256static bool 3257FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS, 3258 QualType DeclType, SourceLocation DeclLoc, 3259 Expr *Init, QualType T2, bool AllowRvalues, 3260 bool AllowExplicit) { 3261 assert(T2->isRecordType() && "Can only find conversions of record types."); 3262 CXXRecordDecl *T2RecordDecl 3263 = dyn_cast<CXXRecordDecl>(T2->getAs<RecordType>()->getDecl()); 3264 3265 OverloadCandidateSet CandidateSet(DeclLoc); 3266 const UnresolvedSetImpl *Conversions 3267 = T2RecordDecl->getVisibleConversionFunctions(); 3268 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 3269 E = Conversions->end(); I != E; ++I) { 3270 NamedDecl *D = *I; 3271 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 3272 if (isa<UsingShadowDecl>(D)) 3273 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 3274 3275 FunctionTemplateDecl *ConvTemplate 3276 = dyn_cast<FunctionTemplateDecl>(D); 3277 CXXConversionDecl *Conv; 3278 if (ConvTemplate) 3279 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 3280 else 3281 Conv = cast<CXXConversionDecl>(D); 3282 3283 // If this is an explicit conversion, and we're not allowed to consider 3284 // explicit conversions, skip it. 3285 if (!AllowExplicit && Conv->isExplicit()) 3286 continue; 3287 3288 if (AllowRvalues) { 3289 bool DerivedToBase = false; 3290 bool ObjCConversion = false; 3291 bool ObjCLifetimeConversion = false; 3292 if (!ConvTemplate && 3293 S.CompareReferenceRelationship( 3294 DeclLoc, 3295 Conv->getConversionType().getNonReferenceType() 3296 .getUnqualifiedType(), 3297 DeclType.getNonReferenceType().getUnqualifiedType(), 3298 DerivedToBase, ObjCConversion, ObjCLifetimeConversion) == 3299 Sema::Ref_Incompatible) 3300 continue; 3301 } else { 3302 // If the conversion function doesn't return a reference type, 3303 // it can't be considered for this conversion. An rvalue reference 3304 // is only acceptable if its referencee is a function type. 3305 3306 const ReferenceType *RefType = 3307 Conv->getConversionType()->getAs<ReferenceType>(); 3308 if (!RefType || 3309 (!RefType->isLValueReferenceType() && 3310 !RefType->getPointeeType()->isFunctionType())) 3311 continue; 3312 } 3313 3314 if (ConvTemplate) 3315 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), ActingDC, 3316 Init, DeclType, CandidateSet); 3317 else 3318 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Init, 3319 DeclType, CandidateSet); 3320 } 3321 3322 OverloadCandidateSet::iterator Best; 3323 switch (CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) { 3324 case OR_Success: 3325 // C++ [over.ics.ref]p1: 3326 // 3327 // [...] If the parameter binds directly to the result of 3328 // applying a conversion function to the argument 3329 // expression, the implicit conversion sequence is a 3330 // user-defined conversion sequence (13.3.3.1.2), with the 3331 // second standard conversion sequence either an identity 3332 // conversion or, if the conversion function returns an 3333 // entity of a type that is a derived class of the parameter 3334 // type, a derived-to-base Conversion. 3335 if (!Best->FinalConversion.DirectBinding) 3336 return false; 3337 3338 if (Best->Function) 3339 S.MarkDeclarationReferenced(DeclLoc, Best->Function); 3340 ICS.setUserDefined(); 3341 ICS.UserDefined.Before = Best->Conversions[0].Standard; 3342 ICS.UserDefined.After = Best->FinalConversion; 3343 ICS.UserDefined.ConversionFunction = Best->Function; 3344 ICS.UserDefined.FoundConversionFunction = Best->FoundDecl.getDecl(); 3345 ICS.UserDefined.EllipsisConversion = false; 3346 assert(ICS.UserDefined.After.ReferenceBinding && 3347 ICS.UserDefined.After.DirectBinding && 3348 "Expected a direct reference binding!"); 3349 return true; 3350 3351 case OR_Ambiguous: 3352 ICS.setAmbiguous(); 3353 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(); 3354 Cand != CandidateSet.end(); ++Cand) 3355 if (Cand->Viable) 3356 ICS.Ambiguous.addConversion(Cand->Function); 3357 return true; 3358 3359 case OR_No_Viable_Function: 3360 case OR_Deleted: 3361 // There was no suitable conversion, or we found a deleted 3362 // conversion; continue with other checks. 3363 return false; 3364 } 3365 3366 return false; 3367} 3368 3369/// \brief Compute an implicit conversion sequence for reference 3370/// initialization. 3371static ImplicitConversionSequence 3372TryReferenceInit(Sema &S, Expr *&Init, QualType DeclType, 3373 SourceLocation DeclLoc, 3374 bool SuppressUserConversions, 3375 bool AllowExplicit) { 3376 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 3377 3378 // Most paths end in a failed conversion. 3379 ImplicitConversionSequence ICS; 3380 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3381 3382 QualType T1 = DeclType->getAs<ReferenceType>()->getPointeeType(); 3383 QualType T2 = Init->getType(); 3384 3385 // If the initializer is the address of an overloaded function, try 3386 // to resolve the overloaded function. If all goes well, T2 is the 3387 // type of the resulting function. 3388 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) { 3389 DeclAccessPair Found; 3390 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Init, DeclType, 3391 false, Found)) 3392 T2 = Fn->getType(); 3393 } 3394 3395 // Compute some basic properties of the types and the initializer. 3396 bool isRValRef = DeclType->isRValueReferenceType(); 3397 bool DerivedToBase = false; 3398 bool ObjCConversion = false; 3399 bool ObjCLifetimeConversion = false; 3400 Expr::Classification InitCategory = Init->Classify(S.Context); 3401 Sema::ReferenceCompareResult RefRelationship 3402 = S.CompareReferenceRelationship(DeclLoc, T1, T2, DerivedToBase, 3403 ObjCConversion, ObjCLifetimeConversion); 3404 3405 3406 // C++0x [dcl.init.ref]p5: 3407 // A reference to type "cv1 T1" is initialized by an expression 3408 // of type "cv2 T2" as follows: 3409 3410 // -- If reference is an lvalue reference and the initializer expression 3411 if (!isRValRef) { 3412 // -- is an lvalue (but is not a bit-field), and "cv1 T1" is 3413 // reference-compatible with "cv2 T2," or 3414 // 3415 // Per C++ [over.ics.ref]p4, we don't check the bit-field property here. 3416 if (InitCategory.isLValue() && 3417 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 3418 // C++ [over.ics.ref]p1: 3419 // When a parameter of reference type binds directly (8.5.3) 3420 // to an argument expression, the implicit conversion sequence 3421 // is the identity conversion, unless the argument expression 3422 // has a type that is a derived class of the parameter type, 3423 // in which case the implicit conversion sequence is a 3424 // derived-to-base Conversion (13.3.3.1). 3425 ICS.setStandard(); 3426 ICS.Standard.First = ICK_Identity; 3427 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3428 : ObjCConversion? ICK_Compatible_Conversion 3429 : ICK_Identity; 3430 ICS.Standard.Third = ICK_Identity; 3431 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3432 ICS.Standard.setToType(0, T2); 3433 ICS.Standard.setToType(1, T1); 3434 ICS.Standard.setToType(2, T1); 3435 ICS.Standard.ReferenceBinding = true; 3436 ICS.Standard.DirectBinding = true; 3437 ICS.Standard.IsLvalueReference = !isRValRef; 3438 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3439 ICS.Standard.BindsToRvalue = false; 3440 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3441 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion; 3442 ICS.Standard.CopyConstructor = 0; 3443 3444 // Nothing more to do: the inaccessibility/ambiguity check for 3445 // derived-to-base conversions is suppressed when we're 3446 // computing the implicit conversion sequence (C++ 3447 // [over.best.ics]p2). 3448 return ICS; 3449 } 3450 3451 // -- has a class type (i.e., T2 is a class type), where T1 is 3452 // not reference-related to T2, and can be implicitly 3453 // converted to an lvalue of type "cv3 T3," where "cv1 T1" 3454 // is reference-compatible with "cv3 T3" 92) (this 3455 // conversion is selected by enumerating the applicable 3456 // conversion functions (13.3.1.6) and choosing the best 3457 // one through overload resolution (13.3)), 3458 if (!SuppressUserConversions && T2->isRecordType() && 3459 !S.RequireCompleteType(DeclLoc, T2, 0) && 3460 RefRelationship == Sema::Ref_Incompatible) { 3461 if (FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3462 Init, T2, /*AllowRvalues=*/false, 3463 AllowExplicit)) 3464 return ICS; 3465 } 3466 } 3467 3468 // -- Otherwise, the reference shall be an lvalue reference to a 3469 // non-volatile const type (i.e., cv1 shall be const), or the reference 3470 // shall be an rvalue reference. 3471 // 3472 // We actually handle one oddity of C++ [over.ics.ref] at this 3473 // point, which is that, due to p2 (which short-circuits reference 3474 // binding by only attempting a simple conversion for non-direct 3475 // bindings) and p3's strange wording, we allow a const volatile 3476 // reference to bind to an rvalue. Hence the check for the presence 3477 // of "const" rather than checking for "const" being the only 3478 // qualifier. 3479 // This is also the point where rvalue references and lvalue inits no longer 3480 // go together. 3481 if (!isRValRef && !T1.isConstQualified()) 3482 return ICS; 3483 3484 // -- If the initializer expression 3485 // 3486 // -- is an xvalue, class prvalue, array prvalue or function 3487 // lvalue and "cv1 T1" is reference-compatible with "cv2 T2", or 3488 if (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification && 3489 (InitCategory.isXValue() || 3490 (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) || 3491 (InitCategory.isLValue() && T2->isFunctionType()))) { 3492 ICS.setStandard(); 3493 ICS.Standard.First = ICK_Identity; 3494 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3495 : ObjCConversion? ICK_Compatible_Conversion 3496 : ICK_Identity; 3497 ICS.Standard.Third = ICK_Identity; 3498 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3499 ICS.Standard.setToType(0, T2); 3500 ICS.Standard.setToType(1, T1); 3501 ICS.Standard.setToType(2, T1); 3502 ICS.Standard.ReferenceBinding = true; 3503 // In C++0x, this is always a direct binding. In C++98/03, it's a direct 3504 // binding unless we're binding to a class prvalue. 3505 // Note: Although xvalues wouldn't normally show up in C++98/03 code, we 3506 // allow the use of rvalue references in C++98/03 for the benefit of 3507 // standard library implementors; therefore, we need the xvalue check here. 3508 ICS.Standard.DirectBinding = 3509 S.getLangOptions().CPlusPlus0x || 3510 (InitCategory.isPRValue() && !T2->isRecordType()); 3511 ICS.Standard.IsLvalueReference = !isRValRef; 3512 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3513 ICS.Standard.BindsToRvalue = InitCategory.isRValue(); 3514 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3515 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion; 3516 ICS.Standard.CopyConstructor = 0; 3517 return ICS; 3518 } 3519 3520 // -- has a class type (i.e., T2 is a class type), where T1 is not 3521 // reference-related to T2, and can be implicitly converted to 3522 // an xvalue, class prvalue, or function lvalue of type 3523 // "cv3 T3", where "cv1 T1" is reference-compatible with 3524 // "cv3 T3", 3525 // 3526 // then the reference is bound to the value of the initializer 3527 // expression in the first case and to the result of the conversion 3528 // in the second case (or, in either case, to an appropriate base 3529 // class subobject). 3530 if (!SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3531 T2->isRecordType() && !S.RequireCompleteType(DeclLoc, T2, 0) && 3532 FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3533 Init, T2, /*AllowRvalues=*/true, 3534 AllowExplicit)) { 3535 // In the second case, if the reference is an rvalue reference 3536 // and the second standard conversion sequence of the 3537 // user-defined conversion sequence includes an lvalue-to-rvalue 3538 // conversion, the program is ill-formed. 3539 if (ICS.isUserDefined() && isRValRef && 3540 ICS.UserDefined.After.First == ICK_Lvalue_To_Rvalue) 3541 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3542 3543 return ICS; 3544 } 3545 3546 // -- Otherwise, a temporary of type "cv1 T1" is created and 3547 // initialized from the initializer expression using the 3548 // rules for a non-reference copy initialization (8.5). The 3549 // reference is then bound to the temporary. If T1 is 3550 // reference-related to T2, cv1 must be the same 3551 // cv-qualification as, or greater cv-qualification than, 3552 // cv2; otherwise, the program is ill-formed. 3553 if (RefRelationship == Sema::Ref_Related) { 3554 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 3555 // we would be reference-compatible or reference-compatible with 3556 // added qualification. But that wasn't the case, so the reference 3557 // initialization fails. 3558 // 3559 // Note that we only want to check address spaces and cvr-qualifiers here. 3560 // ObjC GC and lifetime qualifiers aren't important. 3561 Qualifiers T1Quals = T1.getQualifiers(); 3562 Qualifiers T2Quals = T2.getQualifiers(); 3563 T1Quals.removeObjCGCAttr(); 3564 T1Quals.removeObjCLifetime(); 3565 T2Quals.removeObjCGCAttr(); 3566 T2Quals.removeObjCLifetime(); 3567 if (!T1Quals.compatiblyIncludes(T2Quals)) 3568 return ICS; 3569 } 3570 3571 // If at least one of the types is a class type, the types are not 3572 // related, and we aren't allowed any user conversions, the 3573 // reference binding fails. This case is important for breaking 3574 // recursion, since TryImplicitConversion below will attempt to 3575 // create a temporary through the use of a copy constructor. 3576 if (SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3577 (T1->isRecordType() || T2->isRecordType())) 3578 return ICS; 3579 3580 // If T1 is reference-related to T2 and the reference is an rvalue 3581 // reference, the initializer expression shall not be an lvalue. 3582 if (RefRelationship >= Sema::Ref_Related && 3583 isRValRef && Init->Classify(S.Context).isLValue()) 3584 return ICS; 3585 3586 // C++ [over.ics.ref]p2: 3587 // When a parameter of reference type is not bound directly to 3588 // an argument expression, the conversion sequence is the one 3589 // required to convert the argument expression to the 3590 // underlying type of the reference according to 3591 // 13.3.3.1. Conceptually, this conversion sequence corresponds 3592 // to copy-initializing a temporary of the underlying type with 3593 // the argument expression. Any difference in top-level 3594 // cv-qualification is subsumed by the initialization itself 3595 // and does not constitute a conversion. 3596 ICS = TryImplicitConversion(S, Init, T1, SuppressUserConversions, 3597 /*AllowExplicit=*/false, 3598 /*InOverloadResolution=*/false, 3599 /*CStyle=*/false, 3600 /*AllowObjCWritebackConversion=*/false); 3601 3602 // Of course, that's still a reference binding. 3603 if (ICS.isStandard()) { 3604 ICS.Standard.ReferenceBinding = true; 3605 ICS.Standard.IsLvalueReference = !isRValRef; 3606 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3607 ICS.Standard.BindsToRvalue = true; 3608 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3609 ICS.Standard.ObjCLifetimeConversionBinding = false; 3610 } else if (ICS.isUserDefined()) { 3611 ICS.UserDefined.After.ReferenceBinding = true; 3612 ICS.Standard.IsLvalueReference = !isRValRef; 3613 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3614 ICS.Standard.BindsToRvalue = true; 3615 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3616 ICS.Standard.ObjCLifetimeConversionBinding = false; 3617 } 3618 3619 return ICS; 3620} 3621 3622/// TryCopyInitialization - Try to copy-initialize a value of type 3623/// ToType from the expression From. Return the implicit conversion 3624/// sequence required to pass this argument, which may be a bad 3625/// conversion sequence (meaning that the argument cannot be passed to 3626/// a parameter of this type). If @p SuppressUserConversions, then we 3627/// do not permit any user-defined conversion sequences. 3628static ImplicitConversionSequence 3629TryCopyInitialization(Sema &S, Expr *From, QualType ToType, 3630 bool SuppressUserConversions, 3631 bool InOverloadResolution, 3632 bool AllowObjCWritebackConversion) { 3633 if (ToType->isReferenceType()) 3634 return TryReferenceInit(S, From, ToType, 3635 /*FIXME:*/From->getLocStart(), 3636 SuppressUserConversions, 3637 /*AllowExplicit=*/false); 3638 3639 return TryImplicitConversion(S, From, ToType, 3640 SuppressUserConversions, 3641 /*AllowExplicit=*/false, 3642 InOverloadResolution, 3643 /*CStyle=*/false, 3644 AllowObjCWritebackConversion); 3645} 3646 3647static bool TryCopyInitialization(const CanQualType FromQTy, 3648 const CanQualType ToQTy, 3649 Sema &S, 3650 SourceLocation Loc, 3651 ExprValueKind FromVK) { 3652 OpaqueValueExpr TmpExpr(Loc, FromQTy, FromVK); 3653 ImplicitConversionSequence ICS = 3654 TryCopyInitialization(S, &TmpExpr, ToQTy, true, true, false); 3655 3656 return !ICS.isBad(); 3657} 3658 3659/// TryObjectArgumentInitialization - Try to initialize the object 3660/// parameter of the given member function (@c Method) from the 3661/// expression @p From. 3662static ImplicitConversionSequence 3663TryObjectArgumentInitialization(Sema &S, QualType OrigFromType, 3664 Expr::Classification FromClassification, 3665 CXXMethodDecl *Method, 3666 CXXRecordDecl *ActingContext) { 3667 QualType ClassType = S.Context.getTypeDeclType(ActingContext); 3668 // [class.dtor]p2: A destructor can be invoked for a const, volatile or 3669 // const volatile object. 3670 unsigned Quals = isa<CXXDestructorDecl>(Method) ? 3671 Qualifiers::Const | Qualifiers::Volatile : Method->getTypeQualifiers(); 3672 QualType ImplicitParamType = S.Context.getCVRQualifiedType(ClassType, Quals); 3673 3674 // Set up the conversion sequence as a "bad" conversion, to allow us 3675 // to exit early. 3676 ImplicitConversionSequence ICS; 3677 3678 // We need to have an object of class type. 3679 QualType FromType = OrigFromType; 3680 if (const PointerType *PT = FromType->getAs<PointerType>()) { 3681 FromType = PT->getPointeeType(); 3682 3683 // When we had a pointer, it's implicitly dereferenced, so we 3684 // better have an lvalue. 3685 assert(FromClassification.isLValue()); 3686 } 3687 3688 assert(FromType->isRecordType()); 3689 3690 // C++0x [over.match.funcs]p4: 3691 // For non-static member functions, the type of the implicit object 3692 // parameter is 3693 // 3694 // - "lvalue reference to cv X" for functions declared without a 3695 // ref-qualifier or with the & ref-qualifier 3696 // - "rvalue reference to cv X" for functions declared with the && 3697 // ref-qualifier 3698 // 3699 // where X is the class of which the function is a member and cv is the 3700 // cv-qualification on the member function declaration. 3701 // 3702 // However, when finding an implicit conversion sequence for the argument, we 3703 // are not allowed to create temporaries or perform user-defined conversions 3704 // (C++ [over.match.funcs]p5). We perform a simplified version of 3705 // reference binding here, that allows class rvalues to bind to 3706 // non-constant references. 3707 3708 // First check the qualifiers. 3709 QualType FromTypeCanon = S.Context.getCanonicalType(FromType); 3710 if (ImplicitParamType.getCVRQualifiers() 3711 != FromTypeCanon.getLocalCVRQualifiers() && 3712 !ImplicitParamType.isAtLeastAsQualifiedAs(FromTypeCanon)) { 3713 ICS.setBad(BadConversionSequence::bad_qualifiers, 3714 OrigFromType, ImplicitParamType); 3715 return ICS; 3716 } 3717 3718 // Check that we have either the same type or a derived type. It 3719 // affects the conversion rank. 3720 QualType ClassTypeCanon = S.Context.getCanonicalType(ClassType); 3721 ImplicitConversionKind SecondKind; 3722 if (ClassTypeCanon == FromTypeCanon.getLocalUnqualifiedType()) { 3723 SecondKind = ICK_Identity; 3724 } else if (S.IsDerivedFrom(FromType, ClassType)) 3725 SecondKind = ICK_Derived_To_Base; 3726 else { 3727 ICS.setBad(BadConversionSequence::unrelated_class, 3728 FromType, ImplicitParamType); 3729 return ICS; 3730 } 3731 3732 // Check the ref-qualifier. 3733 switch (Method->getRefQualifier()) { 3734 case RQ_None: 3735 // Do nothing; we don't care about lvalueness or rvalueness. 3736 break; 3737 3738 case RQ_LValue: 3739 if (!FromClassification.isLValue() && Quals != Qualifiers::Const) { 3740 // non-const lvalue reference cannot bind to an rvalue 3741 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, FromType, 3742 ImplicitParamType); 3743 return ICS; 3744 } 3745 break; 3746 3747 case RQ_RValue: 3748 if (!FromClassification.isRValue()) { 3749 // rvalue reference cannot bind to an lvalue 3750 ICS.setBad(BadConversionSequence::rvalue_ref_to_lvalue, FromType, 3751 ImplicitParamType); 3752 return ICS; 3753 } 3754 break; 3755 } 3756 3757 // Success. Mark this as a reference binding. 3758 ICS.setStandard(); 3759 ICS.Standard.setAsIdentityConversion(); 3760 ICS.Standard.Second = SecondKind; 3761 ICS.Standard.setFromType(FromType); 3762 ICS.Standard.setAllToTypes(ImplicitParamType); 3763 ICS.Standard.ReferenceBinding = true; 3764 ICS.Standard.DirectBinding = true; 3765 ICS.Standard.IsLvalueReference = Method->getRefQualifier() != RQ_RValue; 3766 ICS.Standard.BindsToFunctionLvalue = false; 3767 ICS.Standard.BindsToRvalue = FromClassification.isRValue(); 3768 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier 3769 = (Method->getRefQualifier() == RQ_None); 3770 return ICS; 3771} 3772 3773/// PerformObjectArgumentInitialization - Perform initialization of 3774/// the implicit object parameter for the given Method with the given 3775/// expression. 3776ExprResult 3777Sema::PerformObjectArgumentInitialization(Expr *From, 3778 NestedNameSpecifier *Qualifier, 3779 NamedDecl *FoundDecl, 3780 CXXMethodDecl *Method) { 3781 QualType FromRecordType, DestType; 3782 QualType ImplicitParamRecordType = 3783 Method->getThisType(Context)->getAs<PointerType>()->getPointeeType(); 3784 3785 Expr::Classification FromClassification; 3786 if (const PointerType *PT = From->getType()->getAs<PointerType>()) { 3787 FromRecordType = PT->getPointeeType(); 3788 DestType = Method->getThisType(Context); 3789 FromClassification = Expr::Classification::makeSimpleLValue(); 3790 } else { 3791 FromRecordType = From->getType(); 3792 DestType = ImplicitParamRecordType; 3793 FromClassification = From->Classify(Context); 3794 } 3795 3796 // Note that we always use the true parent context when performing 3797 // the actual argument initialization. 3798 ImplicitConversionSequence ICS 3799 = TryObjectArgumentInitialization(*this, From->getType(), FromClassification, 3800 Method, Method->getParent()); 3801 if (ICS.isBad()) { 3802 if (ICS.Bad.Kind == BadConversionSequence::bad_qualifiers) { 3803 Qualifiers FromQs = FromRecordType.getQualifiers(); 3804 Qualifiers ToQs = DestType.getQualifiers(); 3805 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 3806 if (CVR) { 3807 Diag(From->getSourceRange().getBegin(), 3808 diag::err_member_function_call_bad_cvr) 3809 << Method->getDeclName() << FromRecordType << (CVR - 1) 3810 << From->getSourceRange(); 3811 Diag(Method->getLocation(), diag::note_previous_decl) 3812 << Method->getDeclName(); 3813 return ExprError(); 3814 } 3815 } 3816 3817 return Diag(From->getSourceRange().getBegin(), 3818 diag::err_implicit_object_parameter_init) 3819 << ImplicitParamRecordType << FromRecordType << From->getSourceRange(); 3820 } 3821 3822 if (ICS.Standard.Second == ICK_Derived_To_Base) { 3823 ExprResult FromRes = 3824 PerformObjectMemberConversion(From, Qualifier, FoundDecl, Method); 3825 if (FromRes.isInvalid()) 3826 return ExprError(); 3827 From = FromRes.take(); 3828 } 3829 3830 if (!Context.hasSameType(From->getType(), DestType)) 3831 From = ImpCastExprToType(From, DestType, CK_NoOp, 3832 From->getType()->isPointerType() ? VK_RValue : VK_LValue).take(); 3833 return Owned(From); 3834} 3835 3836/// TryContextuallyConvertToBool - Attempt to contextually convert the 3837/// expression From to bool (C++0x [conv]p3). 3838static ImplicitConversionSequence 3839TryContextuallyConvertToBool(Sema &S, Expr *From) { 3840 // FIXME: This is pretty broken. 3841 return TryImplicitConversion(S, From, S.Context.BoolTy, 3842 // FIXME: Are these flags correct? 3843 /*SuppressUserConversions=*/false, 3844 /*AllowExplicit=*/true, 3845 /*InOverloadResolution=*/false, 3846 /*CStyle=*/false, 3847 /*AllowObjCWritebackConversion=*/false); 3848} 3849 3850/// PerformContextuallyConvertToBool - Perform a contextual conversion 3851/// of the expression From to bool (C++0x [conv]p3). 3852ExprResult Sema::PerformContextuallyConvertToBool(Expr *From) { 3853 ImplicitConversionSequence ICS = TryContextuallyConvertToBool(*this, From); 3854 if (!ICS.isBad()) 3855 return PerformImplicitConversion(From, Context.BoolTy, ICS, AA_Converting); 3856 3857 if (!DiagnoseMultipleUserDefinedConversion(From, Context.BoolTy)) 3858 return Diag(From->getSourceRange().getBegin(), 3859 diag::err_typecheck_bool_condition) 3860 << From->getType() << From->getSourceRange(); 3861 return ExprError(); 3862} 3863 3864/// TryContextuallyConvertToObjCId - Attempt to contextually convert the 3865/// expression From to 'id'. 3866static ImplicitConversionSequence 3867TryContextuallyConvertToObjCId(Sema &S, Expr *From) { 3868 QualType Ty = S.Context.getObjCIdType(); 3869 return TryImplicitConversion(S, From, Ty, 3870 // FIXME: Are these flags correct? 3871 /*SuppressUserConversions=*/false, 3872 /*AllowExplicit=*/true, 3873 /*InOverloadResolution=*/false, 3874 /*CStyle=*/false, 3875 /*AllowObjCWritebackConversion=*/false); 3876} 3877 3878/// PerformContextuallyConvertToObjCId - Perform a contextual conversion 3879/// of the expression From to 'id'. 3880ExprResult Sema::PerformContextuallyConvertToObjCId(Expr *From) { 3881 QualType Ty = Context.getObjCIdType(); 3882 ImplicitConversionSequence ICS = TryContextuallyConvertToObjCId(*this, From); 3883 if (!ICS.isBad()) 3884 return PerformImplicitConversion(From, Ty, ICS, AA_Converting); 3885 return ExprError(); 3886} 3887 3888/// \brief Attempt to convert the given expression to an integral or 3889/// enumeration type. 3890/// 3891/// This routine will attempt to convert an expression of class type to an 3892/// integral or enumeration type, if that class type only has a single 3893/// conversion to an integral or enumeration type. 3894/// 3895/// \param Loc The source location of the construct that requires the 3896/// conversion. 3897/// 3898/// \param FromE The expression we're converting from. 3899/// 3900/// \param NotIntDiag The diagnostic to be emitted if the expression does not 3901/// have integral or enumeration type. 3902/// 3903/// \param IncompleteDiag The diagnostic to be emitted if the expression has 3904/// incomplete class type. 3905/// 3906/// \param ExplicitConvDiag The diagnostic to be emitted if we're calling an 3907/// explicit conversion function (because no implicit conversion functions 3908/// were available). This is a recovery mode. 3909/// 3910/// \param ExplicitConvNote The note to be emitted with \p ExplicitConvDiag, 3911/// showing which conversion was picked. 3912/// 3913/// \param AmbigDiag The diagnostic to be emitted if there is more than one 3914/// conversion function that could convert to integral or enumeration type. 3915/// 3916/// \param AmbigNote The note to be emitted with \p AmbigDiag for each 3917/// usable conversion function. 3918/// 3919/// \param ConvDiag The diagnostic to be emitted if we are calling a conversion 3920/// function, which may be an extension in this case. 3921/// 3922/// \returns The expression, converted to an integral or enumeration type if 3923/// successful. 3924ExprResult 3925Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From, 3926 const PartialDiagnostic &NotIntDiag, 3927 const PartialDiagnostic &IncompleteDiag, 3928 const PartialDiagnostic &ExplicitConvDiag, 3929 const PartialDiagnostic &ExplicitConvNote, 3930 const PartialDiagnostic &AmbigDiag, 3931 const PartialDiagnostic &AmbigNote, 3932 const PartialDiagnostic &ConvDiag) { 3933 // We can't perform any more checking for type-dependent expressions. 3934 if (From->isTypeDependent()) 3935 return Owned(From); 3936 3937 // If the expression already has integral or enumeration type, we're golden. 3938 QualType T = From->getType(); 3939 if (T->isIntegralOrEnumerationType()) 3940 return Owned(From); 3941 3942 // FIXME: Check for missing '()' if T is a function type? 3943 3944 // If we don't have a class type in C++, there's no way we can get an 3945 // expression of integral or enumeration type. 3946 const RecordType *RecordTy = T->getAs<RecordType>(); 3947 if (!RecordTy || !getLangOptions().CPlusPlus) { 3948 Diag(Loc, NotIntDiag) 3949 << T << From->getSourceRange(); 3950 return Owned(From); 3951 } 3952 3953 // We must have a complete class type. 3954 if (RequireCompleteType(Loc, T, IncompleteDiag)) 3955 return Owned(From); 3956 3957 // Look for a conversion to an integral or enumeration type. 3958 UnresolvedSet<4> ViableConversions; 3959 UnresolvedSet<4> ExplicitConversions; 3960 const UnresolvedSetImpl *Conversions 3961 = cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions(); 3962 3963 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 3964 E = Conversions->end(); 3965 I != E; 3966 ++I) { 3967 if (CXXConversionDecl *Conversion 3968 = dyn_cast<CXXConversionDecl>((*I)->getUnderlyingDecl())) 3969 if (Conversion->getConversionType().getNonReferenceType() 3970 ->isIntegralOrEnumerationType()) { 3971 if (Conversion->isExplicit()) 3972 ExplicitConversions.addDecl(I.getDecl(), I.getAccess()); 3973 else 3974 ViableConversions.addDecl(I.getDecl(), I.getAccess()); 3975 } 3976 } 3977 3978 switch (ViableConversions.size()) { 3979 case 0: 3980 if (ExplicitConversions.size() == 1) { 3981 DeclAccessPair Found = ExplicitConversions[0]; 3982 CXXConversionDecl *Conversion 3983 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 3984 3985 // The user probably meant to invoke the given explicit 3986 // conversion; use it. 3987 QualType ConvTy 3988 = Conversion->getConversionType().getNonReferenceType(); 3989 std::string TypeStr; 3990 ConvTy.getAsStringInternal(TypeStr, Context.PrintingPolicy); 3991 3992 Diag(Loc, ExplicitConvDiag) 3993 << T << ConvTy 3994 << FixItHint::CreateInsertion(From->getLocStart(), 3995 "static_cast<" + TypeStr + ">(") 3996 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(From->getLocEnd()), 3997 ")"); 3998 Diag(Conversion->getLocation(), ExplicitConvNote) 3999 << ConvTy->isEnumeralType() << ConvTy; 4000 4001 // If we aren't in a SFINAE context, build a call to the 4002 // explicit conversion function. 4003 if (isSFINAEContext()) 4004 return ExprError(); 4005 4006 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 4007 ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion); 4008 if (Result.isInvalid()) 4009 return ExprError(); 4010 4011 From = Result.get(); 4012 } 4013 4014 // We'll complain below about a non-integral condition type. 4015 break; 4016 4017 case 1: { 4018 // Apply this conversion. 4019 DeclAccessPair Found = ViableConversions[0]; 4020 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 4021 4022 CXXConversionDecl *Conversion 4023 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 4024 QualType ConvTy 4025 = Conversion->getConversionType().getNonReferenceType(); 4026 if (ConvDiag.getDiagID()) { 4027 if (isSFINAEContext()) 4028 return ExprError(); 4029 4030 Diag(Loc, ConvDiag) 4031 << T << ConvTy->isEnumeralType() << ConvTy << From->getSourceRange(); 4032 } 4033 4034 ExprResult Result = BuildCXXMemberCallExpr(From, Found, 4035 cast<CXXConversionDecl>(Found->getUnderlyingDecl())); 4036 if (Result.isInvalid()) 4037 return ExprError(); 4038 4039 From = Result.get(); 4040 break; 4041 } 4042 4043 default: 4044 Diag(Loc, AmbigDiag) 4045 << T << From->getSourceRange(); 4046 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) { 4047 CXXConversionDecl *Conv 4048 = cast<CXXConversionDecl>(ViableConversions[I]->getUnderlyingDecl()); 4049 QualType ConvTy = Conv->getConversionType().getNonReferenceType(); 4050 Diag(Conv->getLocation(), AmbigNote) 4051 << ConvTy->isEnumeralType() << ConvTy; 4052 } 4053 return Owned(From); 4054 } 4055 4056 if (!From->getType()->isIntegralOrEnumerationType()) 4057 Diag(Loc, NotIntDiag) 4058 << From->getType() << From->getSourceRange(); 4059 4060 return Owned(From); 4061} 4062 4063/// AddOverloadCandidate - Adds the given function to the set of 4064/// candidate functions, using the given function call arguments. If 4065/// @p SuppressUserConversions, then don't allow user-defined 4066/// conversions via constructors or conversion operators. 4067/// 4068/// \para PartialOverloading true if we are performing "partial" overloading 4069/// based on an incomplete set of function arguments. This feature is used by 4070/// code completion. 4071void 4072Sema::AddOverloadCandidate(FunctionDecl *Function, 4073 DeclAccessPair FoundDecl, 4074 Expr **Args, unsigned NumArgs, 4075 OverloadCandidateSet& CandidateSet, 4076 bool SuppressUserConversions, 4077 bool PartialOverloading) { 4078 const FunctionProtoType* Proto 4079 = dyn_cast<FunctionProtoType>(Function->getType()->getAs<FunctionType>()); 4080 assert(Proto && "Functions without a prototype cannot be overloaded"); 4081 assert(!Function->getDescribedFunctionTemplate() && 4082 "Use AddTemplateOverloadCandidate for function templates"); 4083 4084 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { 4085 if (!isa<CXXConstructorDecl>(Method)) { 4086 // If we get here, it's because we're calling a member function 4087 // that is named without a member access expression (e.g., 4088 // "this->f") that was either written explicitly or created 4089 // implicitly. This can happen with a qualified call to a member 4090 // function, e.g., X::f(). We use an empty type for the implied 4091 // object argument (C++ [over.call.func]p3), and the acting context 4092 // is irrelevant. 4093 AddMethodCandidate(Method, FoundDecl, Method->getParent(), 4094 QualType(), Expr::Classification::makeSimpleLValue(), 4095 Args, NumArgs, CandidateSet, 4096 SuppressUserConversions); 4097 return; 4098 } 4099 // We treat a constructor like a non-member function, since its object 4100 // argument doesn't participate in overload resolution. 4101 } 4102 4103 if (!CandidateSet.isNewCandidate(Function)) 4104 return; 4105 4106 // Overload resolution is always an unevaluated context. 4107 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4108 4109 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Function)){ 4110 // C++ [class.copy]p3: 4111 // A member function template is never instantiated to perform the copy 4112 // of a class object to an object of its class type. 4113 QualType ClassType = Context.getTypeDeclType(Constructor->getParent()); 4114 if (NumArgs == 1 && 4115 Constructor->isSpecializationCopyingObject() && 4116 (Context.hasSameUnqualifiedType(ClassType, Args[0]->getType()) || 4117 IsDerivedFrom(Args[0]->getType(), ClassType))) 4118 return; 4119 } 4120 4121 // Add this candidate 4122 CandidateSet.push_back(OverloadCandidate()); 4123 OverloadCandidate& Candidate = CandidateSet.back(); 4124 Candidate.FoundDecl = FoundDecl; 4125 Candidate.Function = Function; 4126 Candidate.Viable = true; 4127 Candidate.IsSurrogate = false; 4128 Candidate.IgnoreObjectArgument = false; 4129 Candidate.ExplicitCallArguments = NumArgs; 4130 4131 unsigned NumArgsInProto = Proto->getNumArgs(); 4132 4133 // (C++ 13.3.2p2): A candidate function having fewer than m 4134 // parameters is viable only if it has an ellipsis in its parameter 4135 // list (8.3.5). 4136 if ((NumArgs + (PartialOverloading && NumArgs)) > NumArgsInProto && 4137 !Proto->isVariadic()) { 4138 Candidate.Viable = false; 4139 Candidate.FailureKind = ovl_fail_too_many_arguments; 4140 return; 4141 } 4142 4143 // (C++ 13.3.2p2): A candidate function having more than m parameters 4144 // is viable only if the (m+1)st parameter has a default argument 4145 // (8.3.6). For the purposes of overload resolution, the 4146 // parameter list is truncated on the right, so that there are 4147 // exactly m parameters. 4148 unsigned MinRequiredArgs = Function->getMinRequiredArguments(); 4149 if (NumArgs < MinRequiredArgs && !PartialOverloading) { 4150 // Not enough arguments. 4151 Candidate.Viable = false; 4152 Candidate.FailureKind = ovl_fail_too_few_arguments; 4153 return; 4154 } 4155 4156 // Determine the implicit conversion sequences for each of the 4157 // arguments. 4158 Candidate.Conversions.resize(NumArgs); 4159 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4160 if (ArgIdx < NumArgsInProto) { 4161 // (C++ 13.3.2p3): for F to be a viable function, there shall 4162 // exist for each argument an implicit conversion sequence 4163 // (13.3.3.1) that converts that argument to the corresponding 4164 // parameter of F. 4165 QualType ParamType = Proto->getArgType(ArgIdx); 4166 Candidate.Conversions[ArgIdx] 4167 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4168 SuppressUserConversions, 4169 /*InOverloadResolution=*/true, 4170 /*AllowObjCWritebackConversion=*/ 4171 getLangOptions().ObjCAutoRefCount); 4172 if (Candidate.Conversions[ArgIdx].isBad()) { 4173 Candidate.Viable = false; 4174 Candidate.FailureKind = ovl_fail_bad_conversion; 4175 break; 4176 } 4177 } else { 4178 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4179 // argument for which there is no corresponding parameter is 4180 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4181 Candidate.Conversions[ArgIdx].setEllipsis(); 4182 } 4183 } 4184} 4185 4186/// \brief Add all of the function declarations in the given function set to 4187/// the overload canddiate set. 4188void Sema::AddFunctionCandidates(const UnresolvedSetImpl &Fns, 4189 Expr **Args, unsigned NumArgs, 4190 OverloadCandidateSet& CandidateSet, 4191 bool SuppressUserConversions) { 4192 for (UnresolvedSetIterator F = Fns.begin(), E = Fns.end(); F != E; ++F) { 4193 NamedDecl *D = F.getDecl()->getUnderlyingDecl(); 4194 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 4195 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 4196 AddMethodCandidate(cast<CXXMethodDecl>(FD), F.getPair(), 4197 cast<CXXMethodDecl>(FD)->getParent(), 4198 Args[0]->getType(), Args[0]->Classify(Context), 4199 Args + 1, NumArgs - 1, 4200 CandidateSet, SuppressUserConversions); 4201 else 4202 AddOverloadCandidate(FD, F.getPair(), Args, NumArgs, CandidateSet, 4203 SuppressUserConversions); 4204 } else { 4205 FunctionTemplateDecl *FunTmpl = cast<FunctionTemplateDecl>(D); 4206 if (isa<CXXMethodDecl>(FunTmpl->getTemplatedDecl()) && 4207 !cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl())->isStatic()) 4208 AddMethodTemplateCandidate(FunTmpl, F.getPair(), 4209 cast<CXXRecordDecl>(FunTmpl->getDeclContext()), 4210 /*FIXME: explicit args */ 0, 4211 Args[0]->getType(), 4212 Args[0]->Classify(Context), 4213 Args + 1, NumArgs - 1, 4214 CandidateSet, 4215 SuppressUserConversions); 4216 else 4217 AddTemplateOverloadCandidate(FunTmpl, F.getPair(), 4218 /*FIXME: explicit args */ 0, 4219 Args, NumArgs, CandidateSet, 4220 SuppressUserConversions); 4221 } 4222 } 4223} 4224 4225/// AddMethodCandidate - Adds a named decl (which is some kind of 4226/// method) as a method candidate to the given overload set. 4227void Sema::AddMethodCandidate(DeclAccessPair FoundDecl, 4228 QualType ObjectType, 4229 Expr::Classification ObjectClassification, 4230 Expr **Args, unsigned NumArgs, 4231 OverloadCandidateSet& CandidateSet, 4232 bool SuppressUserConversions) { 4233 NamedDecl *Decl = FoundDecl.getDecl(); 4234 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(Decl->getDeclContext()); 4235 4236 if (isa<UsingShadowDecl>(Decl)) 4237 Decl = cast<UsingShadowDecl>(Decl)->getTargetDecl(); 4238 4239 if (FunctionTemplateDecl *TD = dyn_cast<FunctionTemplateDecl>(Decl)) { 4240 assert(isa<CXXMethodDecl>(TD->getTemplatedDecl()) && 4241 "Expected a member function template"); 4242 AddMethodTemplateCandidate(TD, FoundDecl, ActingContext, 4243 /*ExplicitArgs*/ 0, 4244 ObjectType, ObjectClassification, Args, NumArgs, 4245 CandidateSet, 4246 SuppressUserConversions); 4247 } else { 4248 AddMethodCandidate(cast<CXXMethodDecl>(Decl), FoundDecl, ActingContext, 4249 ObjectType, ObjectClassification, Args, NumArgs, 4250 CandidateSet, SuppressUserConversions); 4251 } 4252} 4253 4254/// AddMethodCandidate - Adds the given C++ member function to the set 4255/// of candidate functions, using the given function call arguments 4256/// and the object argument (@c Object). For example, in a call 4257/// @c o.f(a1,a2), @c Object will contain @c o and @c Args will contain 4258/// both @c a1 and @c a2. If @p SuppressUserConversions, then don't 4259/// allow user-defined conversions via constructors or conversion 4260/// operators. 4261void 4262Sema::AddMethodCandidate(CXXMethodDecl *Method, DeclAccessPair FoundDecl, 4263 CXXRecordDecl *ActingContext, QualType ObjectType, 4264 Expr::Classification ObjectClassification, 4265 Expr **Args, unsigned NumArgs, 4266 OverloadCandidateSet& CandidateSet, 4267 bool SuppressUserConversions) { 4268 const FunctionProtoType* Proto 4269 = dyn_cast<FunctionProtoType>(Method->getType()->getAs<FunctionType>()); 4270 assert(Proto && "Methods without a prototype cannot be overloaded"); 4271 assert(!isa<CXXConstructorDecl>(Method) && 4272 "Use AddOverloadCandidate for constructors"); 4273 4274 if (!CandidateSet.isNewCandidate(Method)) 4275 return; 4276 4277 // Overload resolution is always an unevaluated context. 4278 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4279 4280 // Add this candidate 4281 CandidateSet.push_back(OverloadCandidate()); 4282 OverloadCandidate& Candidate = CandidateSet.back(); 4283 Candidate.FoundDecl = FoundDecl; 4284 Candidate.Function = Method; 4285 Candidate.IsSurrogate = false; 4286 Candidate.IgnoreObjectArgument = false; 4287 Candidate.ExplicitCallArguments = NumArgs; 4288 4289 unsigned NumArgsInProto = Proto->getNumArgs(); 4290 4291 // (C++ 13.3.2p2): A candidate function having fewer than m 4292 // parameters is viable only if it has an ellipsis in its parameter 4293 // list (8.3.5). 4294 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4295 Candidate.Viable = false; 4296 Candidate.FailureKind = ovl_fail_too_many_arguments; 4297 return; 4298 } 4299 4300 // (C++ 13.3.2p2): A candidate function having more than m parameters 4301 // is viable only if the (m+1)st parameter has a default argument 4302 // (8.3.6). For the purposes of overload resolution, the 4303 // parameter list is truncated on the right, so that there are 4304 // exactly m parameters. 4305 unsigned MinRequiredArgs = Method->getMinRequiredArguments(); 4306 if (NumArgs < MinRequiredArgs) { 4307 // Not enough arguments. 4308 Candidate.Viable = false; 4309 Candidate.FailureKind = ovl_fail_too_few_arguments; 4310 return; 4311 } 4312 4313 Candidate.Viable = true; 4314 Candidate.Conversions.resize(NumArgs + 1); 4315 4316 if (Method->isStatic() || ObjectType.isNull()) 4317 // The implicit object argument is ignored. 4318 Candidate.IgnoreObjectArgument = true; 4319 else { 4320 // Determine the implicit conversion sequence for the object 4321 // parameter. 4322 Candidate.Conversions[0] 4323 = TryObjectArgumentInitialization(*this, ObjectType, ObjectClassification, 4324 Method, ActingContext); 4325 if (Candidate.Conversions[0].isBad()) { 4326 Candidate.Viable = false; 4327 Candidate.FailureKind = ovl_fail_bad_conversion; 4328 return; 4329 } 4330 } 4331 4332 // Determine the implicit conversion sequences for each of the 4333 // arguments. 4334 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4335 if (ArgIdx < NumArgsInProto) { 4336 // (C++ 13.3.2p3): for F to be a viable function, there shall 4337 // exist for each argument an implicit conversion sequence 4338 // (13.3.3.1) that converts that argument to the corresponding 4339 // parameter of F. 4340 QualType ParamType = Proto->getArgType(ArgIdx); 4341 Candidate.Conversions[ArgIdx + 1] 4342 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4343 SuppressUserConversions, 4344 /*InOverloadResolution=*/true, 4345 /*AllowObjCWritebackConversion=*/ 4346 getLangOptions().ObjCAutoRefCount); 4347 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4348 Candidate.Viable = false; 4349 Candidate.FailureKind = ovl_fail_bad_conversion; 4350 break; 4351 } 4352 } else { 4353 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4354 // argument for which there is no corresponding parameter is 4355 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4356 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4357 } 4358 } 4359} 4360 4361/// \brief Add a C++ member function template as a candidate to the candidate 4362/// set, using template argument deduction to produce an appropriate member 4363/// function template specialization. 4364void 4365Sema::AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl, 4366 DeclAccessPair FoundDecl, 4367 CXXRecordDecl *ActingContext, 4368 TemplateArgumentListInfo *ExplicitTemplateArgs, 4369 QualType ObjectType, 4370 Expr::Classification ObjectClassification, 4371 Expr **Args, unsigned NumArgs, 4372 OverloadCandidateSet& CandidateSet, 4373 bool SuppressUserConversions) { 4374 if (!CandidateSet.isNewCandidate(MethodTmpl)) 4375 return; 4376 4377 // C++ [over.match.funcs]p7: 4378 // In each case where a candidate is a function template, candidate 4379 // function template specializations are generated using template argument 4380 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4381 // candidate functions in the usual way.113) A given name can refer to one 4382 // or more function templates and also to a set of overloaded non-template 4383 // functions. In such a case, the candidate functions generated from each 4384 // function template are combined with the set of non-template candidate 4385 // functions. 4386 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4387 FunctionDecl *Specialization = 0; 4388 if (TemplateDeductionResult Result 4389 = DeduceTemplateArguments(MethodTmpl, ExplicitTemplateArgs, 4390 Args, NumArgs, Specialization, Info)) { 4391 CandidateSet.push_back(OverloadCandidate()); 4392 OverloadCandidate &Candidate = CandidateSet.back(); 4393 Candidate.FoundDecl = FoundDecl; 4394 Candidate.Function = MethodTmpl->getTemplatedDecl(); 4395 Candidate.Viable = false; 4396 Candidate.FailureKind = ovl_fail_bad_deduction; 4397 Candidate.IsSurrogate = false; 4398 Candidate.IgnoreObjectArgument = false; 4399 Candidate.ExplicitCallArguments = NumArgs; 4400 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4401 Info); 4402 return; 4403 } 4404 4405 // Add the function template specialization produced by template argument 4406 // deduction as a candidate. 4407 assert(Specialization && "Missing member function template specialization?"); 4408 assert(isa<CXXMethodDecl>(Specialization) && 4409 "Specialization is not a member function?"); 4410 AddMethodCandidate(cast<CXXMethodDecl>(Specialization), FoundDecl, 4411 ActingContext, ObjectType, ObjectClassification, 4412 Args, NumArgs, CandidateSet, SuppressUserConversions); 4413} 4414 4415/// \brief Add a C++ function template specialization as a candidate 4416/// in the candidate set, using template argument deduction to produce 4417/// an appropriate function template specialization. 4418void 4419Sema::AddTemplateOverloadCandidate(FunctionTemplateDecl *FunctionTemplate, 4420 DeclAccessPair FoundDecl, 4421 TemplateArgumentListInfo *ExplicitTemplateArgs, 4422 Expr **Args, unsigned NumArgs, 4423 OverloadCandidateSet& CandidateSet, 4424 bool SuppressUserConversions) { 4425 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4426 return; 4427 4428 // C++ [over.match.funcs]p7: 4429 // In each case where a candidate is a function template, candidate 4430 // function template specializations are generated using template argument 4431 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4432 // candidate functions in the usual way.113) A given name can refer to one 4433 // or more function templates and also to a set of overloaded non-template 4434 // functions. In such a case, the candidate functions generated from each 4435 // function template are combined with the set of non-template candidate 4436 // functions. 4437 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4438 FunctionDecl *Specialization = 0; 4439 if (TemplateDeductionResult Result 4440 = DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs, 4441 Args, NumArgs, Specialization, Info)) { 4442 CandidateSet.push_back(OverloadCandidate()); 4443 OverloadCandidate &Candidate = CandidateSet.back(); 4444 Candidate.FoundDecl = FoundDecl; 4445 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4446 Candidate.Viable = false; 4447 Candidate.FailureKind = ovl_fail_bad_deduction; 4448 Candidate.IsSurrogate = false; 4449 Candidate.IgnoreObjectArgument = false; 4450 Candidate.ExplicitCallArguments = NumArgs; 4451 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4452 Info); 4453 return; 4454 } 4455 4456 // Add the function template specialization produced by template argument 4457 // deduction as a candidate. 4458 assert(Specialization && "Missing function template specialization?"); 4459 AddOverloadCandidate(Specialization, FoundDecl, Args, NumArgs, CandidateSet, 4460 SuppressUserConversions); 4461} 4462 4463/// AddConversionCandidate - Add a C++ conversion function as a 4464/// candidate in the candidate set (C++ [over.match.conv], 4465/// C++ [over.match.copy]). From is the expression we're converting from, 4466/// and ToType is the type that we're eventually trying to convert to 4467/// (which may or may not be the same type as the type that the 4468/// conversion function produces). 4469void 4470Sema::AddConversionCandidate(CXXConversionDecl *Conversion, 4471 DeclAccessPair FoundDecl, 4472 CXXRecordDecl *ActingContext, 4473 Expr *From, QualType ToType, 4474 OverloadCandidateSet& CandidateSet) { 4475 assert(!Conversion->getDescribedFunctionTemplate() && 4476 "Conversion function templates use AddTemplateConversionCandidate"); 4477 QualType ConvType = Conversion->getConversionType().getNonReferenceType(); 4478 if (!CandidateSet.isNewCandidate(Conversion)) 4479 return; 4480 4481 // Overload resolution is always an unevaluated context. 4482 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4483 4484 // Add this candidate 4485 CandidateSet.push_back(OverloadCandidate()); 4486 OverloadCandidate& Candidate = CandidateSet.back(); 4487 Candidate.FoundDecl = FoundDecl; 4488 Candidate.Function = Conversion; 4489 Candidate.IsSurrogate = false; 4490 Candidate.IgnoreObjectArgument = false; 4491 Candidate.FinalConversion.setAsIdentityConversion(); 4492 Candidate.FinalConversion.setFromType(ConvType); 4493 Candidate.FinalConversion.setAllToTypes(ToType); 4494 Candidate.Viable = true; 4495 Candidate.Conversions.resize(1); 4496 Candidate.ExplicitCallArguments = 1; 4497 4498 // C++ [over.match.funcs]p4: 4499 // For conversion functions, the function is considered to be a member of 4500 // the class of the implicit implied object argument for the purpose of 4501 // defining the type of the implicit object parameter. 4502 // 4503 // Determine the implicit conversion sequence for the implicit 4504 // object parameter. 4505 QualType ImplicitParamType = From->getType(); 4506 if (const PointerType *FromPtrType = ImplicitParamType->getAs<PointerType>()) 4507 ImplicitParamType = FromPtrType->getPointeeType(); 4508 CXXRecordDecl *ConversionContext 4509 = cast<CXXRecordDecl>(ImplicitParamType->getAs<RecordType>()->getDecl()); 4510 4511 Candidate.Conversions[0] 4512 = TryObjectArgumentInitialization(*this, From->getType(), 4513 From->Classify(Context), 4514 Conversion, ConversionContext); 4515 4516 if (Candidate.Conversions[0].isBad()) { 4517 Candidate.Viable = false; 4518 Candidate.FailureKind = ovl_fail_bad_conversion; 4519 return; 4520 } 4521 4522 // We won't go through a user-define type conversion function to convert a 4523 // derived to base as such conversions are given Conversion Rank. They only 4524 // go through a copy constructor. 13.3.3.1.2-p4 [over.ics.user] 4525 QualType FromCanon 4526 = Context.getCanonicalType(From->getType().getUnqualifiedType()); 4527 QualType ToCanon = Context.getCanonicalType(ToType).getUnqualifiedType(); 4528 if (FromCanon == ToCanon || IsDerivedFrom(FromCanon, ToCanon)) { 4529 Candidate.Viable = false; 4530 Candidate.FailureKind = ovl_fail_trivial_conversion; 4531 return; 4532 } 4533 4534 // To determine what the conversion from the result of calling the 4535 // conversion function to the type we're eventually trying to 4536 // convert to (ToType), we need to synthesize a call to the 4537 // conversion function and attempt copy initialization from it. This 4538 // makes sure that we get the right semantics with respect to 4539 // lvalues/rvalues and the type. Fortunately, we can allocate this 4540 // call on the stack and we don't need its arguments to be 4541 // well-formed. 4542 DeclRefExpr ConversionRef(Conversion, Conversion->getType(), 4543 VK_LValue, From->getLocStart()); 4544 ImplicitCastExpr ConversionFn(ImplicitCastExpr::OnStack, 4545 Context.getPointerType(Conversion->getType()), 4546 CK_FunctionToPointerDecay, 4547 &ConversionRef, VK_RValue); 4548 4549 QualType ConversionType = Conversion->getConversionType(); 4550 if (RequireCompleteType(From->getLocStart(), ConversionType, 0)) { 4551 Candidate.Viable = false; 4552 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4553 return; 4554 } 4555 4556 ExprValueKind VK = Expr::getValueKindForType(ConversionType); 4557 4558 // Note that it is safe to allocate CallExpr on the stack here because 4559 // there are 0 arguments (i.e., nothing is allocated using ASTContext's 4560 // allocator). 4561 QualType CallResultType = ConversionType.getNonLValueExprType(Context); 4562 CallExpr Call(Context, &ConversionFn, 0, 0, CallResultType, VK, 4563 From->getLocStart()); 4564 ImplicitConversionSequence ICS = 4565 TryCopyInitialization(*this, &Call, ToType, 4566 /*SuppressUserConversions=*/true, 4567 /*InOverloadResolution=*/false, 4568 /*AllowObjCWritebackConversion=*/false); 4569 4570 switch (ICS.getKind()) { 4571 case ImplicitConversionSequence::StandardConversion: 4572 Candidate.FinalConversion = ICS.Standard; 4573 4574 // C++ [over.ics.user]p3: 4575 // If the user-defined conversion is specified by a specialization of a 4576 // conversion function template, the second standard conversion sequence 4577 // shall have exact match rank. 4578 if (Conversion->getPrimaryTemplate() && 4579 GetConversionRank(ICS.Standard.Second) != ICR_Exact_Match) { 4580 Candidate.Viable = false; 4581 Candidate.FailureKind = ovl_fail_final_conversion_not_exact; 4582 } 4583 4584 // C++0x [dcl.init.ref]p5: 4585 // In the second case, if the reference is an rvalue reference and 4586 // the second standard conversion sequence of the user-defined 4587 // conversion sequence includes an lvalue-to-rvalue conversion, the 4588 // program is ill-formed. 4589 if (ToType->isRValueReferenceType() && 4590 ICS.Standard.First == ICK_Lvalue_To_Rvalue) { 4591 Candidate.Viable = false; 4592 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4593 } 4594 break; 4595 4596 case ImplicitConversionSequence::BadConversion: 4597 Candidate.Viable = false; 4598 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4599 break; 4600 4601 default: 4602 assert(false && 4603 "Can only end up with a standard conversion sequence or failure"); 4604 } 4605} 4606 4607/// \brief Adds a conversion function template specialization 4608/// candidate to the overload set, using template argument deduction 4609/// to deduce the template arguments of the conversion function 4610/// template from the type that we are converting to (C++ 4611/// [temp.deduct.conv]). 4612void 4613Sema::AddTemplateConversionCandidate(FunctionTemplateDecl *FunctionTemplate, 4614 DeclAccessPair FoundDecl, 4615 CXXRecordDecl *ActingDC, 4616 Expr *From, QualType ToType, 4617 OverloadCandidateSet &CandidateSet) { 4618 assert(isa<CXXConversionDecl>(FunctionTemplate->getTemplatedDecl()) && 4619 "Only conversion function templates permitted here"); 4620 4621 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4622 return; 4623 4624 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4625 CXXConversionDecl *Specialization = 0; 4626 if (TemplateDeductionResult Result 4627 = DeduceTemplateArguments(FunctionTemplate, ToType, 4628 Specialization, Info)) { 4629 CandidateSet.push_back(OverloadCandidate()); 4630 OverloadCandidate &Candidate = CandidateSet.back(); 4631 Candidate.FoundDecl = FoundDecl; 4632 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4633 Candidate.Viable = false; 4634 Candidate.FailureKind = ovl_fail_bad_deduction; 4635 Candidate.IsSurrogate = false; 4636 Candidate.IgnoreObjectArgument = false; 4637 Candidate.ExplicitCallArguments = 1; 4638 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4639 Info); 4640 return; 4641 } 4642 4643 // Add the conversion function template specialization produced by 4644 // template argument deduction as a candidate. 4645 assert(Specialization && "Missing function template specialization?"); 4646 AddConversionCandidate(Specialization, FoundDecl, ActingDC, From, ToType, 4647 CandidateSet); 4648} 4649 4650/// AddSurrogateCandidate - Adds a "surrogate" candidate function that 4651/// converts the given @c Object to a function pointer via the 4652/// conversion function @c Conversion, and then attempts to call it 4653/// with the given arguments (C++ [over.call.object]p2-4). Proto is 4654/// the type of function that we'll eventually be calling. 4655void Sema::AddSurrogateCandidate(CXXConversionDecl *Conversion, 4656 DeclAccessPair FoundDecl, 4657 CXXRecordDecl *ActingContext, 4658 const FunctionProtoType *Proto, 4659 Expr *Object, 4660 Expr **Args, unsigned NumArgs, 4661 OverloadCandidateSet& CandidateSet) { 4662 if (!CandidateSet.isNewCandidate(Conversion)) 4663 return; 4664 4665 // Overload resolution is always an unevaluated context. 4666 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4667 4668 CandidateSet.push_back(OverloadCandidate()); 4669 OverloadCandidate& Candidate = CandidateSet.back(); 4670 Candidate.FoundDecl = FoundDecl; 4671 Candidate.Function = 0; 4672 Candidate.Surrogate = Conversion; 4673 Candidate.Viable = true; 4674 Candidate.IsSurrogate = true; 4675 Candidate.IgnoreObjectArgument = false; 4676 Candidate.Conversions.resize(NumArgs + 1); 4677 Candidate.ExplicitCallArguments = NumArgs; 4678 4679 // Determine the implicit conversion sequence for the implicit 4680 // object parameter. 4681 ImplicitConversionSequence ObjectInit 4682 = TryObjectArgumentInitialization(*this, Object->getType(), 4683 Object->Classify(Context), 4684 Conversion, ActingContext); 4685 if (ObjectInit.isBad()) { 4686 Candidate.Viable = false; 4687 Candidate.FailureKind = ovl_fail_bad_conversion; 4688 Candidate.Conversions[0] = ObjectInit; 4689 return; 4690 } 4691 4692 // The first conversion is actually a user-defined conversion whose 4693 // first conversion is ObjectInit's standard conversion (which is 4694 // effectively a reference binding). Record it as such. 4695 Candidate.Conversions[0].setUserDefined(); 4696 Candidate.Conversions[0].UserDefined.Before = ObjectInit.Standard; 4697 Candidate.Conversions[0].UserDefined.EllipsisConversion = false; 4698 Candidate.Conversions[0].UserDefined.ConversionFunction = Conversion; 4699 Candidate.Conversions[0].UserDefined.FoundConversionFunction 4700 = FoundDecl.getDecl(); 4701 Candidate.Conversions[0].UserDefined.After 4702 = Candidate.Conversions[0].UserDefined.Before; 4703 Candidate.Conversions[0].UserDefined.After.setAsIdentityConversion(); 4704 4705 // Find the 4706 unsigned NumArgsInProto = Proto->getNumArgs(); 4707 4708 // (C++ 13.3.2p2): A candidate function having fewer than m 4709 // parameters is viable only if it has an ellipsis in its parameter 4710 // list (8.3.5). 4711 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4712 Candidate.Viable = false; 4713 Candidate.FailureKind = ovl_fail_too_many_arguments; 4714 return; 4715 } 4716 4717 // Function types don't have any default arguments, so just check if 4718 // we have enough arguments. 4719 if (NumArgs < NumArgsInProto) { 4720 // Not enough arguments. 4721 Candidate.Viable = false; 4722 Candidate.FailureKind = ovl_fail_too_few_arguments; 4723 return; 4724 } 4725 4726 // Determine the implicit conversion sequences for each of the 4727 // arguments. 4728 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4729 if (ArgIdx < NumArgsInProto) { 4730 // (C++ 13.3.2p3): for F to be a viable function, there shall 4731 // exist for each argument an implicit conversion sequence 4732 // (13.3.3.1) that converts that argument to the corresponding 4733 // parameter of F. 4734 QualType ParamType = Proto->getArgType(ArgIdx); 4735 Candidate.Conversions[ArgIdx + 1] 4736 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4737 /*SuppressUserConversions=*/false, 4738 /*InOverloadResolution=*/false, 4739 /*AllowObjCWritebackConversion=*/ 4740 getLangOptions().ObjCAutoRefCount); 4741 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4742 Candidate.Viable = false; 4743 Candidate.FailureKind = ovl_fail_bad_conversion; 4744 break; 4745 } 4746 } else { 4747 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4748 // argument for which there is no corresponding parameter is 4749 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4750 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4751 } 4752 } 4753} 4754 4755/// \brief Add overload candidates for overloaded operators that are 4756/// member functions. 4757/// 4758/// Add the overloaded operator candidates that are member functions 4759/// for the operator Op that was used in an operator expression such 4760/// as "x Op y". , Args/NumArgs provides the operator arguments, and 4761/// CandidateSet will store the added overload candidates. (C++ 4762/// [over.match.oper]). 4763void Sema::AddMemberOperatorCandidates(OverloadedOperatorKind Op, 4764 SourceLocation OpLoc, 4765 Expr **Args, unsigned NumArgs, 4766 OverloadCandidateSet& CandidateSet, 4767 SourceRange OpRange) { 4768 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 4769 4770 // C++ [over.match.oper]p3: 4771 // For a unary operator @ with an operand of a type whose 4772 // cv-unqualified version is T1, and for a binary operator @ with 4773 // a left operand of a type whose cv-unqualified version is T1 and 4774 // a right operand of a type whose cv-unqualified version is T2, 4775 // three sets of candidate functions, designated member 4776 // candidates, non-member candidates and built-in candidates, are 4777 // constructed as follows: 4778 QualType T1 = Args[0]->getType(); 4779 4780 // -- If T1 is a class type, the set of member candidates is the 4781 // result of the qualified lookup of T1::operator@ 4782 // (13.3.1.1.1); otherwise, the set of member candidates is 4783 // empty. 4784 if (const RecordType *T1Rec = T1->getAs<RecordType>()) { 4785 // Complete the type if it can be completed. Otherwise, we're done. 4786 if (RequireCompleteType(OpLoc, T1, PDiag())) 4787 return; 4788 4789 LookupResult Operators(*this, OpName, OpLoc, LookupOrdinaryName); 4790 LookupQualifiedName(Operators, T1Rec->getDecl()); 4791 Operators.suppressDiagnostics(); 4792 4793 for (LookupResult::iterator Oper = Operators.begin(), 4794 OperEnd = Operators.end(); 4795 Oper != OperEnd; 4796 ++Oper) 4797 AddMethodCandidate(Oper.getPair(), Args[0]->getType(), 4798 Args[0]->Classify(Context), Args + 1, NumArgs - 1, 4799 CandidateSet, 4800 /* SuppressUserConversions = */ false); 4801 } 4802} 4803 4804/// AddBuiltinCandidate - Add a candidate for a built-in 4805/// operator. ResultTy and ParamTys are the result and parameter types 4806/// of the built-in candidate, respectively. Args and NumArgs are the 4807/// arguments being passed to the candidate. IsAssignmentOperator 4808/// should be true when this built-in candidate is an assignment 4809/// operator. NumContextualBoolArguments is the number of arguments 4810/// (at the beginning of the argument list) that will be contextually 4811/// converted to bool. 4812void Sema::AddBuiltinCandidate(QualType ResultTy, QualType *ParamTys, 4813 Expr **Args, unsigned NumArgs, 4814 OverloadCandidateSet& CandidateSet, 4815 bool IsAssignmentOperator, 4816 unsigned NumContextualBoolArguments) { 4817 // Overload resolution is always an unevaluated context. 4818 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4819 4820 // Add this candidate 4821 CandidateSet.push_back(OverloadCandidate()); 4822 OverloadCandidate& Candidate = CandidateSet.back(); 4823 Candidate.FoundDecl = DeclAccessPair::make(0, AS_none); 4824 Candidate.Function = 0; 4825 Candidate.IsSurrogate = false; 4826 Candidate.IgnoreObjectArgument = false; 4827 Candidate.BuiltinTypes.ResultTy = ResultTy; 4828 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 4829 Candidate.BuiltinTypes.ParamTypes[ArgIdx] = ParamTys[ArgIdx]; 4830 4831 // Determine the implicit conversion sequences for each of the 4832 // arguments. 4833 Candidate.Viable = true; 4834 Candidate.Conversions.resize(NumArgs); 4835 Candidate.ExplicitCallArguments = NumArgs; 4836 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4837 // C++ [over.match.oper]p4: 4838 // For the built-in assignment operators, conversions of the 4839 // left operand are restricted as follows: 4840 // -- no temporaries are introduced to hold the left operand, and 4841 // -- no user-defined conversions are applied to the left 4842 // operand to achieve a type match with the left-most 4843 // parameter of a built-in candidate. 4844 // 4845 // We block these conversions by turning off user-defined 4846 // conversions, since that is the only way that initialization of 4847 // a reference to a non-class type can occur from something that 4848 // is not of the same type. 4849 if (ArgIdx < NumContextualBoolArguments) { 4850 assert(ParamTys[ArgIdx] == Context.BoolTy && 4851 "Contextual conversion to bool requires bool type"); 4852 Candidate.Conversions[ArgIdx] 4853 = TryContextuallyConvertToBool(*this, Args[ArgIdx]); 4854 } else { 4855 Candidate.Conversions[ArgIdx] 4856 = TryCopyInitialization(*this, Args[ArgIdx], ParamTys[ArgIdx], 4857 ArgIdx == 0 && IsAssignmentOperator, 4858 /*InOverloadResolution=*/false, 4859 /*AllowObjCWritebackConversion=*/ 4860 getLangOptions().ObjCAutoRefCount); 4861 } 4862 if (Candidate.Conversions[ArgIdx].isBad()) { 4863 Candidate.Viable = false; 4864 Candidate.FailureKind = ovl_fail_bad_conversion; 4865 break; 4866 } 4867 } 4868} 4869 4870/// BuiltinCandidateTypeSet - A set of types that will be used for the 4871/// candidate operator functions for built-in operators (C++ 4872/// [over.built]). The types are separated into pointer types and 4873/// enumeration types. 4874class BuiltinCandidateTypeSet { 4875 /// TypeSet - A set of types. 4876 typedef llvm::SmallPtrSet<QualType, 8> TypeSet; 4877 4878 /// PointerTypes - The set of pointer types that will be used in the 4879 /// built-in candidates. 4880 TypeSet PointerTypes; 4881 4882 /// MemberPointerTypes - The set of member pointer types that will be 4883 /// used in the built-in candidates. 4884 TypeSet MemberPointerTypes; 4885 4886 /// EnumerationTypes - The set of enumeration types that will be 4887 /// used in the built-in candidates. 4888 TypeSet EnumerationTypes; 4889 4890 /// \brief The set of vector types that will be used in the built-in 4891 /// candidates. 4892 TypeSet VectorTypes; 4893 4894 /// \brief A flag indicating non-record types are viable candidates 4895 bool HasNonRecordTypes; 4896 4897 /// \brief A flag indicating whether either arithmetic or enumeration types 4898 /// were present in the candidate set. 4899 bool HasArithmeticOrEnumeralTypes; 4900 4901 /// \brief A flag indicating whether the nullptr type was present in the 4902 /// candidate set. 4903 bool HasNullPtrType; 4904 4905 /// Sema - The semantic analysis instance where we are building the 4906 /// candidate type set. 4907 Sema &SemaRef; 4908 4909 /// Context - The AST context in which we will build the type sets. 4910 ASTContext &Context; 4911 4912 bool AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 4913 const Qualifiers &VisibleQuals); 4914 bool AddMemberPointerWithMoreQualifiedTypeVariants(QualType Ty); 4915 4916public: 4917 /// iterator - Iterates through the types that are part of the set. 4918 typedef TypeSet::iterator iterator; 4919 4920 BuiltinCandidateTypeSet(Sema &SemaRef) 4921 : HasNonRecordTypes(false), 4922 HasArithmeticOrEnumeralTypes(false), 4923 HasNullPtrType(false), 4924 SemaRef(SemaRef), 4925 Context(SemaRef.Context) { } 4926 4927 void AddTypesConvertedFrom(QualType Ty, 4928 SourceLocation Loc, 4929 bool AllowUserConversions, 4930 bool AllowExplicitConversions, 4931 const Qualifiers &VisibleTypeConversionsQuals); 4932 4933 /// pointer_begin - First pointer type found; 4934 iterator pointer_begin() { return PointerTypes.begin(); } 4935 4936 /// pointer_end - Past the last pointer type found; 4937 iterator pointer_end() { return PointerTypes.end(); } 4938 4939 /// member_pointer_begin - First member pointer type found; 4940 iterator member_pointer_begin() { return MemberPointerTypes.begin(); } 4941 4942 /// member_pointer_end - Past the last member pointer type found; 4943 iterator member_pointer_end() { return MemberPointerTypes.end(); } 4944 4945 /// enumeration_begin - First enumeration type found; 4946 iterator enumeration_begin() { return EnumerationTypes.begin(); } 4947 4948 /// enumeration_end - Past the last enumeration type found; 4949 iterator enumeration_end() { return EnumerationTypes.end(); } 4950 4951 iterator vector_begin() { return VectorTypes.begin(); } 4952 iterator vector_end() { return VectorTypes.end(); } 4953 4954 bool hasNonRecordTypes() { return HasNonRecordTypes; } 4955 bool hasArithmeticOrEnumeralTypes() { return HasArithmeticOrEnumeralTypes; } 4956 bool hasNullPtrType() const { return HasNullPtrType; } 4957}; 4958 4959/// AddPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty to 4960/// the set of pointer types along with any more-qualified variants of 4961/// that type. For example, if @p Ty is "int const *", this routine 4962/// will add "int const *", "int const volatile *", "int const 4963/// restrict *", and "int const volatile restrict *" to the set of 4964/// pointer types. Returns true if the add of @p Ty itself succeeded, 4965/// false otherwise. 4966/// 4967/// FIXME: what to do about extended qualifiers? 4968bool 4969BuiltinCandidateTypeSet::AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 4970 const Qualifiers &VisibleQuals) { 4971 4972 // Insert this type. 4973 if (!PointerTypes.insert(Ty)) 4974 return false; 4975 4976 QualType PointeeTy; 4977 const PointerType *PointerTy = Ty->getAs<PointerType>(); 4978 bool buildObjCPtr = false; 4979 if (!PointerTy) { 4980 if (const ObjCObjectPointerType *PTy = Ty->getAs<ObjCObjectPointerType>()) { 4981 PointeeTy = PTy->getPointeeType(); 4982 buildObjCPtr = true; 4983 } 4984 else 4985 assert(false && "type was not a pointer type!"); 4986 } 4987 else 4988 PointeeTy = PointerTy->getPointeeType(); 4989 4990 // Don't add qualified variants of arrays. For one, they're not allowed 4991 // (the qualifier would sink to the element type), and for another, the 4992 // only overload situation where it matters is subscript or pointer +- int, 4993 // and those shouldn't have qualifier variants anyway. 4994 if (PointeeTy->isArrayType()) 4995 return true; 4996 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 4997 if (const ConstantArrayType *Array =Context.getAsConstantArrayType(PointeeTy)) 4998 BaseCVR = Array->getElementType().getCVRQualifiers(); 4999 bool hasVolatile = VisibleQuals.hasVolatile(); 5000 bool hasRestrict = VisibleQuals.hasRestrict(); 5001 5002 // Iterate through all strict supersets of BaseCVR. 5003 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 5004 if ((CVR | BaseCVR) != CVR) continue; 5005 // Skip over Volatile/Restrict if no Volatile/Restrict found anywhere 5006 // in the types. 5007 if ((CVR & Qualifiers::Volatile) && !hasVolatile) continue; 5008 if ((CVR & Qualifiers::Restrict) && !hasRestrict) continue; 5009 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 5010 if (!buildObjCPtr) 5011 PointerTypes.insert(Context.getPointerType(QPointeeTy)); 5012 else 5013 PointerTypes.insert(Context.getObjCObjectPointerType(QPointeeTy)); 5014 } 5015 5016 return true; 5017} 5018 5019/// AddMemberPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty 5020/// to the set of pointer types along with any more-qualified variants of 5021/// that type. For example, if @p Ty is "int const *", this routine 5022/// will add "int const *", "int const volatile *", "int const 5023/// restrict *", and "int const volatile restrict *" to the set of 5024/// pointer types. Returns true if the add of @p Ty itself succeeded, 5025/// false otherwise. 5026/// 5027/// FIXME: what to do about extended qualifiers? 5028bool 5029BuiltinCandidateTypeSet::AddMemberPointerWithMoreQualifiedTypeVariants( 5030 QualType Ty) { 5031 // Insert this type. 5032 if (!MemberPointerTypes.insert(Ty)) 5033 return false; 5034 5035 const MemberPointerType *PointerTy = Ty->getAs<MemberPointerType>(); 5036 assert(PointerTy && "type was not a member pointer type!"); 5037 5038 QualType PointeeTy = PointerTy->getPointeeType(); 5039 // Don't add qualified variants of arrays. For one, they're not allowed 5040 // (the qualifier would sink to the element type), and for another, the 5041 // only overload situation where it matters is subscript or pointer +- int, 5042 // and those shouldn't have qualifier variants anyway. 5043 if (PointeeTy->isArrayType()) 5044 return true; 5045 const Type *ClassTy = PointerTy->getClass(); 5046 5047 // Iterate through all strict supersets of the pointee type's CVR 5048 // qualifiers. 5049 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 5050 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 5051 if ((CVR | BaseCVR) != CVR) continue; 5052 5053 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 5054 MemberPointerTypes.insert( 5055 Context.getMemberPointerType(QPointeeTy, ClassTy)); 5056 } 5057 5058 return true; 5059} 5060 5061/// AddTypesConvertedFrom - Add each of the types to which the type @p 5062/// Ty can be implicit converted to the given set of @p Types. We're 5063/// primarily interested in pointer types and enumeration types. We also 5064/// take member pointer types, for the conditional operator. 5065/// AllowUserConversions is true if we should look at the conversion 5066/// functions of a class type, and AllowExplicitConversions if we 5067/// should also include the explicit conversion functions of a class 5068/// type. 5069void 5070BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty, 5071 SourceLocation Loc, 5072 bool AllowUserConversions, 5073 bool AllowExplicitConversions, 5074 const Qualifiers &VisibleQuals) { 5075 // Only deal with canonical types. 5076 Ty = Context.getCanonicalType(Ty); 5077 5078 // Look through reference types; they aren't part of the type of an 5079 // expression for the purposes of conversions. 5080 if (const ReferenceType *RefTy = Ty->getAs<ReferenceType>()) 5081 Ty = RefTy->getPointeeType(); 5082 5083 // If we're dealing with an array type, decay to the pointer. 5084 if (Ty->isArrayType()) 5085 Ty = SemaRef.Context.getArrayDecayedType(Ty); 5086 5087 // Otherwise, we don't care about qualifiers on the type. 5088 Ty = Ty.getLocalUnqualifiedType(); 5089 5090 // Flag if we ever add a non-record type. 5091 const RecordType *TyRec = Ty->getAs<RecordType>(); 5092 HasNonRecordTypes = HasNonRecordTypes || !TyRec; 5093 5094 // Flag if we encounter an arithmetic type. 5095 HasArithmeticOrEnumeralTypes = 5096 HasArithmeticOrEnumeralTypes || Ty->isArithmeticType(); 5097 5098 if (Ty->isObjCIdType() || Ty->isObjCClassType()) 5099 PointerTypes.insert(Ty); 5100 else if (Ty->getAs<PointerType>() || Ty->getAs<ObjCObjectPointerType>()) { 5101 // Insert our type, and its more-qualified variants, into the set 5102 // of types. 5103 if (!AddPointerWithMoreQualifiedTypeVariants(Ty, VisibleQuals)) 5104 return; 5105 } else if (Ty->isMemberPointerType()) { 5106 // Member pointers are far easier, since the pointee can't be converted. 5107 if (!AddMemberPointerWithMoreQualifiedTypeVariants(Ty)) 5108 return; 5109 } else if (Ty->isEnumeralType()) { 5110 HasArithmeticOrEnumeralTypes = true; 5111 EnumerationTypes.insert(Ty); 5112 } else if (Ty->isVectorType()) { 5113 // We treat vector types as arithmetic types in many contexts as an 5114 // extension. 5115 HasArithmeticOrEnumeralTypes = true; 5116 VectorTypes.insert(Ty); 5117 } else if (Ty->isNullPtrType()) { 5118 HasNullPtrType = true; 5119 } else if (AllowUserConversions && TyRec) { 5120 // No conversion functions in incomplete types. 5121 if (SemaRef.RequireCompleteType(Loc, Ty, 0)) 5122 return; 5123 5124 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 5125 const UnresolvedSetImpl *Conversions 5126 = ClassDecl->getVisibleConversionFunctions(); 5127 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 5128 E = Conversions->end(); I != E; ++I) { 5129 NamedDecl *D = I.getDecl(); 5130 if (isa<UsingShadowDecl>(D)) 5131 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 5132 5133 // Skip conversion function templates; they don't tell us anything 5134 // about which builtin types we can convert to. 5135 if (isa<FunctionTemplateDecl>(D)) 5136 continue; 5137 5138 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 5139 if (AllowExplicitConversions || !Conv->isExplicit()) { 5140 AddTypesConvertedFrom(Conv->getConversionType(), Loc, false, false, 5141 VisibleQuals); 5142 } 5143 } 5144 } 5145} 5146 5147/// \brief Helper function for AddBuiltinOperatorCandidates() that adds 5148/// the volatile- and non-volatile-qualified assignment operators for the 5149/// given type to the candidate set. 5150static void AddBuiltinAssignmentOperatorCandidates(Sema &S, 5151 QualType T, 5152 Expr **Args, 5153 unsigned NumArgs, 5154 OverloadCandidateSet &CandidateSet) { 5155 QualType ParamTypes[2]; 5156 5157 // T& operator=(T&, T) 5158 ParamTypes[0] = S.Context.getLValueReferenceType(T); 5159 ParamTypes[1] = T; 5160 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5161 /*IsAssignmentOperator=*/true); 5162 5163 if (!S.Context.getCanonicalType(T).isVolatileQualified()) { 5164 // volatile T& operator=(volatile T&, T) 5165 ParamTypes[0] 5166 = S.Context.getLValueReferenceType(S.Context.getVolatileType(T)); 5167 ParamTypes[1] = T; 5168 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5169 /*IsAssignmentOperator=*/true); 5170 } 5171} 5172 5173/// CollectVRQualifiers - This routine returns Volatile/Restrict qualifiers, 5174/// if any, found in visible type conversion functions found in ArgExpr's type. 5175static Qualifiers CollectVRQualifiers(ASTContext &Context, Expr* ArgExpr) { 5176 Qualifiers VRQuals; 5177 const RecordType *TyRec; 5178 if (const MemberPointerType *RHSMPType = 5179 ArgExpr->getType()->getAs<MemberPointerType>()) 5180 TyRec = RHSMPType->getClass()->getAs<RecordType>(); 5181 else 5182 TyRec = ArgExpr->getType()->getAs<RecordType>(); 5183 if (!TyRec) { 5184 // Just to be safe, assume the worst case. 5185 VRQuals.addVolatile(); 5186 VRQuals.addRestrict(); 5187 return VRQuals; 5188 } 5189 5190 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 5191 if (!ClassDecl->hasDefinition()) 5192 return VRQuals; 5193 5194 const UnresolvedSetImpl *Conversions = 5195 ClassDecl->getVisibleConversionFunctions(); 5196 5197 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 5198 E = Conversions->end(); I != E; ++I) { 5199 NamedDecl *D = I.getDecl(); 5200 if (isa<UsingShadowDecl>(D)) 5201 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 5202 if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(D)) { 5203 QualType CanTy = Context.getCanonicalType(Conv->getConversionType()); 5204 if (const ReferenceType *ResTypeRef = CanTy->getAs<ReferenceType>()) 5205 CanTy = ResTypeRef->getPointeeType(); 5206 // Need to go down the pointer/mempointer chain and add qualifiers 5207 // as see them. 5208 bool done = false; 5209 while (!done) { 5210 if (const PointerType *ResTypePtr = CanTy->getAs<PointerType>()) 5211 CanTy = ResTypePtr->getPointeeType(); 5212 else if (const MemberPointerType *ResTypeMPtr = 5213 CanTy->getAs<MemberPointerType>()) 5214 CanTy = ResTypeMPtr->getPointeeType(); 5215 else 5216 done = true; 5217 if (CanTy.isVolatileQualified()) 5218 VRQuals.addVolatile(); 5219 if (CanTy.isRestrictQualified()) 5220 VRQuals.addRestrict(); 5221 if (VRQuals.hasRestrict() && VRQuals.hasVolatile()) 5222 return VRQuals; 5223 } 5224 } 5225 } 5226 return VRQuals; 5227} 5228 5229namespace { 5230 5231/// \brief Helper class to manage the addition of builtin operator overload 5232/// candidates. It provides shared state and utility methods used throughout 5233/// the process, as well as a helper method to add each group of builtin 5234/// operator overloads from the standard to a candidate set. 5235class BuiltinOperatorOverloadBuilder { 5236 // Common instance state available to all overload candidate addition methods. 5237 Sema &S; 5238 Expr **Args; 5239 unsigned NumArgs; 5240 Qualifiers VisibleTypeConversionsQuals; 5241 bool HasArithmeticOrEnumeralCandidateType; 5242 SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes; 5243 OverloadCandidateSet &CandidateSet; 5244 5245 // Define some constants used to index and iterate over the arithemetic types 5246 // provided via the getArithmeticType() method below. 5247 // The "promoted arithmetic types" are the arithmetic 5248 // types are that preserved by promotion (C++ [over.built]p2). 5249 static const unsigned FirstIntegralType = 3; 5250 static const unsigned LastIntegralType = 18; 5251 static const unsigned FirstPromotedIntegralType = 3, 5252 LastPromotedIntegralType = 9; 5253 static const unsigned FirstPromotedArithmeticType = 0, 5254 LastPromotedArithmeticType = 9; 5255 static const unsigned NumArithmeticTypes = 18; 5256 5257 /// \brief Get the canonical type for a given arithmetic type index. 5258 CanQualType getArithmeticType(unsigned index) { 5259 assert(index < NumArithmeticTypes); 5260 static CanQualType ASTContext::* const 5261 ArithmeticTypes[NumArithmeticTypes] = { 5262 // Start of promoted types. 5263 &ASTContext::FloatTy, 5264 &ASTContext::DoubleTy, 5265 &ASTContext::LongDoubleTy, 5266 5267 // Start of integral types. 5268 &ASTContext::IntTy, 5269 &ASTContext::LongTy, 5270 &ASTContext::LongLongTy, 5271 &ASTContext::UnsignedIntTy, 5272 &ASTContext::UnsignedLongTy, 5273 &ASTContext::UnsignedLongLongTy, 5274 // End of promoted types. 5275 5276 &ASTContext::BoolTy, 5277 &ASTContext::CharTy, 5278 &ASTContext::WCharTy, 5279 &ASTContext::Char16Ty, 5280 &ASTContext::Char32Ty, 5281 &ASTContext::SignedCharTy, 5282 &ASTContext::ShortTy, 5283 &ASTContext::UnsignedCharTy, 5284 &ASTContext::UnsignedShortTy, 5285 // End of integral types. 5286 // FIXME: What about complex? 5287 }; 5288 return S.Context.*ArithmeticTypes[index]; 5289 } 5290 5291 /// \brief Gets the canonical type resulting from the usual arithemetic 5292 /// converions for the given arithmetic types. 5293 CanQualType getUsualArithmeticConversions(unsigned L, unsigned R) { 5294 // Accelerator table for performing the usual arithmetic conversions. 5295 // The rules are basically: 5296 // - if either is floating-point, use the wider floating-point 5297 // - if same signedness, use the higher rank 5298 // - if same size, use unsigned of the higher rank 5299 // - use the larger type 5300 // These rules, together with the axiom that higher ranks are 5301 // never smaller, are sufficient to precompute all of these results 5302 // *except* when dealing with signed types of higher rank. 5303 // (we could precompute SLL x UI for all known platforms, but it's 5304 // better not to make any assumptions). 5305 enum PromotedType { 5306 Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL, Dep=-1 5307 }; 5308 static PromotedType ConversionsTable[LastPromotedArithmeticType] 5309 [LastPromotedArithmeticType] = { 5310 /* Flt*/ { Flt, Dbl, LDbl, Flt, Flt, Flt, Flt, Flt, Flt }, 5311 /* Dbl*/ { Dbl, Dbl, LDbl, Dbl, Dbl, Dbl, Dbl, Dbl, Dbl }, 5312 /*LDbl*/ { LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl }, 5313 /* SI*/ { Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL }, 5314 /* SL*/ { Flt, Dbl, LDbl, SL, SL, SLL, Dep, UL, ULL }, 5315 /* SLL*/ { Flt, Dbl, LDbl, SLL, SLL, SLL, Dep, Dep, ULL }, 5316 /* UI*/ { Flt, Dbl, LDbl, UI, Dep, Dep, UI, UL, ULL }, 5317 /* UL*/ { Flt, Dbl, LDbl, UL, UL, Dep, UL, UL, ULL }, 5318 /* ULL*/ { Flt, Dbl, LDbl, ULL, ULL, ULL, ULL, ULL, ULL }, 5319 }; 5320 5321 assert(L < LastPromotedArithmeticType); 5322 assert(R < LastPromotedArithmeticType); 5323 int Idx = ConversionsTable[L][R]; 5324 5325 // Fast path: the table gives us a concrete answer. 5326 if (Idx != Dep) return getArithmeticType(Idx); 5327 5328 // Slow path: we need to compare widths. 5329 // An invariant is that the signed type has higher rank. 5330 CanQualType LT = getArithmeticType(L), 5331 RT = getArithmeticType(R); 5332 unsigned LW = S.Context.getIntWidth(LT), 5333 RW = S.Context.getIntWidth(RT); 5334 5335 // If they're different widths, use the signed type. 5336 if (LW > RW) return LT; 5337 else if (LW < RW) return RT; 5338 5339 // Otherwise, use the unsigned type of the signed type's rank. 5340 if (L == SL || R == SL) return S.Context.UnsignedLongTy; 5341 assert(L == SLL || R == SLL); 5342 return S.Context.UnsignedLongLongTy; 5343 } 5344 5345 /// \brief Helper method to factor out the common pattern of adding overloads 5346 /// for '++' and '--' builtin operators. 5347 void addPlusPlusMinusMinusStyleOverloads(QualType CandidateTy, 5348 bool HasVolatile) { 5349 QualType ParamTypes[2] = { 5350 S.Context.getLValueReferenceType(CandidateTy), 5351 S.Context.IntTy 5352 }; 5353 5354 // Non-volatile version. 5355 if (NumArgs == 1) 5356 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5357 else 5358 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5359 5360 // Use a heuristic to reduce number of builtin candidates in the set: 5361 // add volatile version only if there are conversions to a volatile type. 5362 if (HasVolatile) { 5363 ParamTypes[0] = 5364 S.Context.getLValueReferenceType( 5365 S.Context.getVolatileType(CandidateTy)); 5366 if (NumArgs == 1) 5367 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5368 else 5369 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5370 } 5371 } 5372 5373public: 5374 BuiltinOperatorOverloadBuilder( 5375 Sema &S, Expr **Args, unsigned NumArgs, 5376 Qualifiers VisibleTypeConversionsQuals, 5377 bool HasArithmeticOrEnumeralCandidateType, 5378 SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes, 5379 OverloadCandidateSet &CandidateSet) 5380 : S(S), Args(Args), NumArgs(NumArgs), 5381 VisibleTypeConversionsQuals(VisibleTypeConversionsQuals), 5382 HasArithmeticOrEnumeralCandidateType( 5383 HasArithmeticOrEnumeralCandidateType), 5384 CandidateTypes(CandidateTypes), 5385 CandidateSet(CandidateSet) { 5386 // Validate some of our static helper constants in debug builds. 5387 assert(getArithmeticType(FirstPromotedIntegralType) == S.Context.IntTy && 5388 "Invalid first promoted integral type"); 5389 assert(getArithmeticType(LastPromotedIntegralType - 1) 5390 == S.Context.UnsignedLongLongTy && 5391 "Invalid last promoted integral type"); 5392 assert(getArithmeticType(FirstPromotedArithmeticType) 5393 == S.Context.FloatTy && 5394 "Invalid first promoted arithmetic type"); 5395 assert(getArithmeticType(LastPromotedArithmeticType - 1) 5396 == S.Context.UnsignedLongLongTy && 5397 "Invalid last promoted arithmetic type"); 5398 } 5399 5400 // C++ [over.built]p3: 5401 // 5402 // For every pair (T, VQ), where T is an arithmetic type, and VQ 5403 // is either volatile or empty, there exist candidate operator 5404 // functions of the form 5405 // 5406 // VQ T& operator++(VQ T&); 5407 // T operator++(VQ T&, int); 5408 // 5409 // C++ [over.built]p4: 5410 // 5411 // For every pair (T, VQ), where T is an arithmetic type other 5412 // than bool, and VQ is either volatile or empty, there exist 5413 // candidate operator functions of the form 5414 // 5415 // VQ T& operator--(VQ T&); 5416 // T operator--(VQ T&, int); 5417 void addPlusPlusMinusMinusArithmeticOverloads(OverloadedOperatorKind Op) { 5418 if (!HasArithmeticOrEnumeralCandidateType) 5419 return; 5420 5421 for (unsigned Arith = (Op == OO_PlusPlus? 0 : 1); 5422 Arith < NumArithmeticTypes; ++Arith) { 5423 addPlusPlusMinusMinusStyleOverloads( 5424 getArithmeticType(Arith), 5425 VisibleTypeConversionsQuals.hasVolatile()); 5426 } 5427 } 5428 5429 // C++ [over.built]p5: 5430 // 5431 // For every pair (T, VQ), where T is a cv-qualified or 5432 // cv-unqualified object type, and VQ is either volatile or 5433 // empty, there exist candidate operator functions of the form 5434 // 5435 // T*VQ& operator++(T*VQ&); 5436 // T*VQ& operator--(T*VQ&); 5437 // T* operator++(T*VQ&, int); 5438 // T* operator--(T*VQ&, int); 5439 void addPlusPlusMinusMinusPointerOverloads() { 5440 for (BuiltinCandidateTypeSet::iterator 5441 Ptr = CandidateTypes[0].pointer_begin(), 5442 PtrEnd = CandidateTypes[0].pointer_end(); 5443 Ptr != PtrEnd; ++Ptr) { 5444 // Skip pointer types that aren't pointers to object types. 5445 if (!(*Ptr)->getPointeeType()->isObjectType()) 5446 continue; 5447 5448 addPlusPlusMinusMinusStyleOverloads(*Ptr, 5449 (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5450 VisibleTypeConversionsQuals.hasVolatile())); 5451 } 5452 } 5453 5454 // C++ [over.built]p6: 5455 // For every cv-qualified or cv-unqualified object type T, there 5456 // exist candidate operator functions of the form 5457 // 5458 // T& operator*(T*); 5459 // 5460 // C++ [over.built]p7: 5461 // For every function type T that does not have cv-qualifiers or a 5462 // ref-qualifier, there exist candidate operator functions of the form 5463 // T& operator*(T*); 5464 void addUnaryStarPointerOverloads() { 5465 for (BuiltinCandidateTypeSet::iterator 5466 Ptr = CandidateTypes[0].pointer_begin(), 5467 PtrEnd = CandidateTypes[0].pointer_end(); 5468 Ptr != PtrEnd; ++Ptr) { 5469 QualType ParamTy = *Ptr; 5470 QualType PointeeTy = ParamTy->getPointeeType(); 5471 if (!PointeeTy->isObjectType() && !PointeeTy->isFunctionType()) 5472 continue; 5473 5474 if (const FunctionProtoType *Proto =PointeeTy->getAs<FunctionProtoType>()) 5475 if (Proto->getTypeQuals() || Proto->getRefQualifier()) 5476 continue; 5477 5478 S.AddBuiltinCandidate(S.Context.getLValueReferenceType(PointeeTy), 5479 &ParamTy, Args, 1, CandidateSet); 5480 } 5481 } 5482 5483 // C++ [over.built]p9: 5484 // For every promoted arithmetic type T, there exist candidate 5485 // operator functions of the form 5486 // 5487 // T operator+(T); 5488 // T operator-(T); 5489 void addUnaryPlusOrMinusArithmeticOverloads() { 5490 if (!HasArithmeticOrEnumeralCandidateType) 5491 return; 5492 5493 for (unsigned Arith = FirstPromotedArithmeticType; 5494 Arith < LastPromotedArithmeticType; ++Arith) { 5495 QualType ArithTy = getArithmeticType(Arith); 5496 S.AddBuiltinCandidate(ArithTy, &ArithTy, Args, 1, CandidateSet); 5497 } 5498 5499 // Extension: We also add these operators for vector types. 5500 for (BuiltinCandidateTypeSet::iterator 5501 Vec = CandidateTypes[0].vector_begin(), 5502 VecEnd = CandidateTypes[0].vector_end(); 5503 Vec != VecEnd; ++Vec) { 5504 QualType VecTy = *Vec; 5505 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5506 } 5507 } 5508 5509 // C++ [over.built]p8: 5510 // For every type T, there exist candidate operator functions of 5511 // the form 5512 // 5513 // T* operator+(T*); 5514 void addUnaryPlusPointerOverloads() { 5515 for (BuiltinCandidateTypeSet::iterator 5516 Ptr = CandidateTypes[0].pointer_begin(), 5517 PtrEnd = CandidateTypes[0].pointer_end(); 5518 Ptr != PtrEnd; ++Ptr) { 5519 QualType ParamTy = *Ptr; 5520 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet); 5521 } 5522 } 5523 5524 // C++ [over.built]p10: 5525 // For every promoted integral type T, there exist candidate 5526 // operator functions of the form 5527 // 5528 // T operator~(T); 5529 void addUnaryTildePromotedIntegralOverloads() { 5530 if (!HasArithmeticOrEnumeralCandidateType) 5531 return; 5532 5533 for (unsigned Int = FirstPromotedIntegralType; 5534 Int < LastPromotedIntegralType; ++Int) { 5535 QualType IntTy = getArithmeticType(Int); 5536 S.AddBuiltinCandidate(IntTy, &IntTy, Args, 1, CandidateSet); 5537 } 5538 5539 // Extension: We also add this operator for vector types. 5540 for (BuiltinCandidateTypeSet::iterator 5541 Vec = CandidateTypes[0].vector_begin(), 5542 VecEnd = CandidateTypes[0].vector_end(); 5543 Vec != VecEnd; ++Vec) { 5544 QualType VecTy = *Vec; 5545 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5546 } 5547 } 5548 5549 // C++ [over.match.oper]p16: 5550 // For every pointer to member type T, there exist candidate operator 5551 // functions of the form 5552 // 5553 // bool operator==(T,T); 5554 // bool operator!=(T,T); 5555 void addEqualEqualOrNotEqualMemberPointerOverloads() { 5556 /// Set of (canonical) types that we've already handled. 5557 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5558 5559 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5560 for (BuiltinCandidateTypeSet::iterator 5561 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5562 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5563 MemPtr != MemPtrEnd; 5564 ++MemPtr) { 5565 // Don't add the same builtin candidate twice. 5566 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5567 continue; 5568 5569 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 5570 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5571 CandidateSet); 5572 } 5573 } 5574 } 5575 5576 // C++ [over.built]p15: 5577 // 5578 // For every T, where T is an enumeration type, a pointer type, or 5579 // std::nullptr_t, there exist candidate operator functions of the form 5580 // 5581 // bool operator<(T, T); 5582 // bool operator>(T, T); 5583 // bool operator<=(T, T); 5584 // bool operator>=(T, T); 5585 // bool operator==(T, T); 5586 // bool operator!=(T, T); 5587 void addRelationalPointerOrEnumeralOverloads() { 5588 // C++ [over.built]p1: 5589 // If there is a user-written candidate with the same name and parameter 5590 // types as a built-in candidate operator function, the built-in operator 5591 // function is hidden and is not included in the set of candidate 5592 // functions. 5593 // 5594 // The text is actually in a note, but if we don't implement it then we end 5595 // up with ambiguities when the user provides an overloaded operator for 5596 // an enumeration type. Note that only enumeration types have this problem, 5597 // so we track which enumeration types we've seen operators for. Also, the 5598 // only other overloaded operator with enumeration argumenst, operator=, 5599 // cannot be overloaded for enumeration types, so this is the only place 5600 // where we must suppress candidates like this. 5601 llvm::DenseSet<std::pair<CanQualType, CanQualType> > 5602 UserDefinedBinaryOperators; 5603 5604 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5605 if (CandidateTypes[ArgIdx].enumeration_begin() != 5606 CandidateTypes[ArgIdx].enumeration_end()) { 5607 for (OverloadCandidateSet::iterator C = CandidateSet.begin(), 5608 CEnd = CandidateSet.end(); 5609 C != CEnd; ++C) { 5610 if (!C->Viable || !C->Function || C->Function->getNumParams() != 2) 5611 continue; 5612 5613 QualType FirstParamType = 5614 C->Function->getParamDecl(0)->getType().getUnqualifiedType(); 5615 QualType SecondParamType = 5616 C->Function->getParamDecl(1)->getType().getUnqualifiedType(); 5617 5618 // Skip if either parameter isn't of enumeral type. 5619 if (!FirstParamType->isEnumeralType() || 5620 !SecondParamType->isEnumeralType()) 5621 continue; 5622 5623 // Add this operator to the set of known user-defined operators. 5624 UserDefinedBinaryOperators.insert( 5625 std::make_pair(S.Context.getCanonicalType(FirstParamType), 5626 S.Context.getCanonicalType(SecondParamType))); 5627 } 5628 } 5629 } 5630 5631 /// Set of (canonical) types that we've already handled. 5632 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5633 5634 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5635 for (BuiltinCandidateTypeSet::iterator 5636 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 5637 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 5638 Ptr != PtrEnd; ++Ptr) { 5639 // Don't add the same builtin candidate twice. 5640 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5641 continue; 5642 5643 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5644 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5645 CandidateSet); 5646 } 5647 for (BuiltinCandidateTypeSet::iterator 5648 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5649 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5650 Enum != EnumEnd; ++Enum) { 5651 CanQualType CanonType = S.Context.getCanonicalType(*Enum); 5652 5653 // Don't add the same builtin candidate twice, or if a user defined 5654 // candidate exists. 5655 if (!AddedTypes.insert(CanonType) || 5656 UserDefinedBinaryOperators.count(std::make_pair(CanonType, 5657 CanonType))) 5658 continue; 5659 5660 QualType ParamTypes[2] = { *Enum, *Enum }; 5661 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5662 CandidateSet); 5663 } 5664 5665 if (CandidateTypes[ArgIdx].hasNullPtrType()) { 5666 CanQualType NullPtrTy = S.Context.getCanonicalType(S.Context.NullPtrTy); 5667 if (AddedTypes.insert(NullPtrTy) && 5668 !UserDefinedBinaryOperators.count(std::make_pair(NullPtrTy, 5669 NullPtrTy))) { 5670 QualType ParamTypes[2] = { NullPtrTy, NullPtrTy }; 5671 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5672 CandidateSet); 5673 } 5674 } 5675 } 5676 } 5677 5678 // C++ [over.built]p13: 5679 // 5680 // For every cv-qualified or cv-unqualified object type T 5681 // there exist candidate operator functions of the form 5682 // 5683 // T* operator+(T*, ptrdiff_t); 5684 // T& operator[](T*, ptrdiff_t); [BELOW] 5685 // T* operator-(T*, ptrdiff_t); 5686 // T* operator+(ptrdiff_t, T*); 5687 // T& operator[](ptrdiff_t, T*); [BELOW] 5688 // 5689 // C++ [over.built]p14: 5690 // 5691 // For every T, where T is a pointer to object type, there 5692 // exist candidate operator functions of the form 5693 // 5694 // ptrdiff_t operator-(T, T); 5695 void addBinaryPlusOrMinusPointerOverloads(OverloadedOperatorKind Op) { 5696 /// Set of (canonical) types that we've already handled. 5697 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5698 5699 for (int Arg = 0; Arg < 2; ++Arg) { 5700 QualType AsymetricParamTypes[2] = { 5701 S.Context.getPointerDiffType(), 5702 S.Context.getPointerDiffType(), 5703 }; 5704 for (BuiltinCandidateTypeSet::iterator 5705 Ptr = CandidateTypes[Arg].pointer_begin(), 5706 PtrEnd = CandidateTypes[Arg].pointer_end(); 5707 Ptr != PtrEnd; ++Ptr) { 5708 QualType PointeeTy = (*Ptr)->getPointeeType(); 5709 if (!PointeeTy->isObjectType()) 5710 continue; 5711 5712 AsymetricParamTypes[Arg] = *Ptr; 5713 if (Arg == 0 || Op == OO_Plus) { 5714 // operator+(T*, ptrdiff_t) or operator-(T*, ptrdiff_t) 5715 // T* operator+(ptrdiff_t, T*); 5716 S.AddBuiltinCandidate(*Ptr, AsymetricParamTypes, Args, 2, 5717 CandidateSet); 5718 } 5719 if (Op == OO_Minus) { 5720 // ptrdiff_t operator-(T, T); 5721 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5722 continue; 5723 5724 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5725 S.AddBuiltinCandidate(S.Context.getPointerDiffType(), ParamTypes, 5726 Args, 2, CandidateSet); 5727 } 5728 } 5729 } 5730 } 5731 5732 // C++ [over.built]p12: 5733 // 5734 // For every pair of promoted arithmetic types L and R, there 5735 // exist candidate operator functions of the form 5736 // 5737 // LR operator*(L, R); 5738 // LR operator/(L, R); 5739 // LR operator+(L, R); 5740 // LR operator-(L, R); 5741 // bool operator<(L, R); 5742 // bool operator>(L, R); 5743 // bool operator<=(L, R); 5744 // bool operator>=(L, R); 5745 // bool operator==(L, R); 5746 // bool operator!=(L, R); 5747 // 5748 // where LR is the result of the usual arithmetic conversions 5749 // between types L and R. 5750 // 5751 // C++ [over.built]p24: 5752 // 5753 // For every pair of promoted arithmetic types L and R, there exist 5754 // candidate operator functions of the form 5755 // 5756 // LR operator?(bool, L, R); 5757 // 5758 // where LR is the result of the usual arithmetic conversions 5759 // between types L and R. 5760 // Our candidates ignore the first parameter. 5761 void addGenericBinaryArithmeticOverloads(bool isComparison) { 5762 if (!HasArithmeticOrEnumeralCandidateType) 5763 return; 5764 5765 for (unsigned Left = FirstPromotedArithmeticType; 5766 Left < LastPromotedArithmeticType; ++Left) { 5767 for (unsigned Right = FirstPromotedArithmeticType; 5768 Right < LastPromotedArithmeticType; ++Right) { 5769 QualType LandR[2] = { getArithmeticType(Left), 5770 getArithmeticType(Right) }; 5771 QualType Result = 5772 isComparison ? S.Context.BoolTy 5773 : getUsualArithmeticConversions(Left, Right); 5774 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5775 } 5776 } 5777 5778 // Extension: Add the binary operators ==, !=, <, <=, >=, >, *, /, and the 5779 // conditional operator for vector types. 5780 for (BuiltinCandidateTypeSet::iterator 5781 Vec1 = CandidateTypes[0].vector_begin(), 5782 Vec1End = CandidateTypes[0].vector_end(); 5783 Vec1 != Vec1End; ++Vec1) { 5784 for (BuiltinCandidateTypeSet::iterator 5785 Vec2 = CandidateTypes[1].vector_begin(), 5786 Vec2End = CandidateTypes[1].vector_end(); 5787 Vec2 != Vec2End; ++Vec2) { 5788 QualType LandR[2] = { *Vec1, *Vec2 }; 5789 QualType Result = S.Context.BoolTy; 5790 if (!isComparison) { 5791 if ((*Vec1)->isExtVectorType() || !(*Vec2)->isExtVectorType()) 5792 Result = *Vec1; 5793 else 5794 Result = *Vec2; 5795 } 5796 5797 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5798 } 5799 } 5800 } 5801 5802 // C++ [over.built]p17: 5803 // 5804 // For every pair of promoted integral types L and R, there 5805 // exist candidate operator functions of the form 5806 // 5807 // LR operator%(L, R); 5808 // LR operator&(L, R); 5809 // LR operator^(L, R); 5810 // LR operator|(L, R); 5811 // L operator<<(L, R); 5812 // L operator>>(L, R); 5813 // 5814 // where LR is the result of the usual arithmetic conversions 5815 // between types L and R. 5816 void addBinaryBitwiseArithmeticOverloads(OverloadedOperatorKind Op) { 5817 if (!HasArithmeticOrEnumeralCandidateType) 5818 return; 5819 5820 for (unsigned Left = FirstPromotedIntegralType; 5821 Left < LastPromotedIntegralType; ++Left) { 5822 for (unsigned Right = FirstPromotedIntegralType; 5823 Right < LastPromotedIntegralType; ++Right) { 5824 QualType LandR[2] = { getArithmeticType(Left), 5825 getArithmeticType(Right) }; 5826 QualType Result = (Op == OO_LessLess || Op == OO_GreaterGreater) 5827 ? LandR[0] 5828 : getUsualArithmeticConversions(Left, Right); 5829 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5830 } 5831 } 5832 } 5833 5834 // C++ [over.built]p20: 5835 // 5836 // For every pair (T, VQ), where T is an enumeration or 5837 // pointer to member type and VQ is either volatile or 5838 // empty, there exist candidate operator functions of the form 5839 // 5840 // VQ T& operator=(VQ T&, T); 5841 void addAssignmentMemberPointerOrEnumeralOverloads() { 5842 /// Set of (canonical) types that we've already handled. 5843 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5844 5845 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 5846 for (BuiltinCandidateTypeSet::iterator 5847 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5848 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5849 Enum != EnumEnd; ++Enum) { 5850 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 5851 continue; 5852 5853 AddBuiltinAssignmentOperatorCandidates(S, *Enum, Args, 2, 5854 CandidateSet); 5855 } 5856 5857 for (BuiltinCandidateTypeSet::iterator 5858 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5859 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5860 MemPtr != MemPtrEnd; ++MemPtr) { 5861 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5862 continue; 5863 5864 AddBuiltinAssignmentOperatorCandidates(S, *MemPtr, Args, 2, 5865 CandidateSet); 5866 } 5867 } 5868 } 5869 5870 // C++ [over.built]p19: 5871 // 5872 // For every pair (T, VQ), where T is any type and VQ is either 5873 // volatile or empty, there exist candidate operator functions 5874 // of the form 5875 // 5876 // T*VQ& operator=(T*VQ&, T*); 5877 // 5878 // C++ [over.built]p21: 5879 // 5880 // For every pair (T, VQ), where T is a cv-qualified or 5881 // cv-unqualified object type and VQ is either volatile or 5882 // empty, there exist candidate operator functions of the form 5883 // 5884 // T*VQ& operator+=(T*VQ&, ptrdiff_t); 5885 // T*VQ& operator-=(T*VQ&, ptrdiff_t); 5886 void addAssignmentPointerOverloads(bool isEqualOp) { 5887 /// Set of (canonical) types that we've already handled. 5888 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5889 5890 for (BuiltinCandidateTypeSet::iterator 5891 Ptr = CandidateTypes[0].pointer_begin(), 5892 PtrEnd = CandidateTypes[0].pointer_end(); 5893 Ptr != PtrEnd; ++Ptr) { 5894 // If this is operator=, keep track of the builtin candidates we added. 5895 if (isEqualOp) 5896 AddedTypes.insert(S.Context.getCanonicalType(*Ptr)); 5897 else if (!(*Ptr)->getPointeeType()->isObjectType()) 5898 continue; 5899 5900 // non-volatile version 5901 QualType ParamTypes[2] = { 5902 S.Context.getLValueReferenceType(*Ptr), 5903 isEqualOp ? *Ptr : S.Context.getPointerDiffType(), 5904 }; 5905 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5906 /*IsAssigmentOperator=*/ isEqualOp); 5907 5908 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5909 VisibleTypeConversionsQuals.hasVolatile()) { 5910 // volatile version 5911 ParamTypes[0] = 5912 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 5913 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5914 /*IsAssigmentOperator=*/isEqualOp); 5915 } 5916 } 5917 5918 if (isEqualOp) { 5919 for (BuiltinCandidateTypeSet::iterator 5920 Ptr = CandidateTypes[1].pointer_begin(), 5921 PtrEnd = CandidateTypes[1].pointer_end(); 5922 Ptr != PtrEnd; ++Ptr) { 5923 // Make sure we don't add the same candidate twice. 5924 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5925 continue; 5926 5927 QualType ParamTypes[2] = { 5928 S.Context.getLValueReferenceType(*Ptr), 5929 *Ptr, 5930 }; 5931 5932 // non-volatile version 5933 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5934 /*IsAssigmentOperator=*/true); 5935 5936 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5937 VisibleTypeConversionsQuals.hasVolatile()) { 5938 // volatile version 5939 ParamTypes[0] = 5940 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 5941 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5942 CandidateSet, /*IsAssigmentOperator=*/true); 5943 } 5944 } 5945 } 5946 } 5947 5948 // C++ [over.built]p18: 5949 // 5950 // For every triple (L, VQ, R), where L is an arithmetic type, 5951 // VQ is either volatile or empty, and R is a promoted 5952 // arithmetic type, there exist candidate operator functions of 5953 // the form 5954 // 5955 // VQ L& operator=(VQ L&, R); 5956 // VQ L& operator*=(VQ L&, R); 5957 // VQ L& operator/=(VQ L&, R); 5958 // VQ L& operator+=(VQ L&, R); 5959 // VQ L& operator-=(VQ L&, R); 5960 void addAssignmentArithmeticOverloads(bool isEqualOp) { 5961 if (!HasArithmeticOrEnumeralCandidateType) 5962 return; 5963 5964 for (unsigned Left = 0; Left < NumArithmeticTypes; ++Left) { 5965 for (unsigned Right = FirstPromotedArithmeticType; 5966 Right < LastPromotedArithmeticType; ++Right) { 5967 QualType ParamTypes[2]; 5968 ParamTypes[1] = getArithmeticType(Right); 5969 5970 // Add this built-in operator as a candidate (VQ is empty). 5971 ParamTypes[0] = 5972 S.Context.getLValueReferenceType(getArithmeticType(Left)); 5973 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5974 /*IsAssigmentOperator=*/isEqualOp); 5975 5976 // Add this built-in operator as a candidate (VQ is 'volatile'). 5977 if (VisibleTypeConversionsQuals.hasVolatile()) { 5978 ParamTypes[0] = 5979 S.Context.getVolatileType(getArithmeticType(Left)); 5980 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 5981 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5982 CandidateSet, 5983 /*IsAssigmentOperator=*/isEqualOp); 5984 } 5985 } 5986 } 5987 5988 // Extension: Add the binary operators =, +=, -=, *=, /= for vector types. 5989 for (BuiltinCandidateTypeSet::iterator 5990 Vec1 = CandidateTypes[0].vector_begin(), 5991 Vec1End = CandidateTypes[0].vector_end(); 5992 Vec1 != Vec1End; ++Vec1) { 5993 for (BuiltinCandidateTypeSet::iterator 5994 Vec2 = CandidateTypes[1].vector_begin(), 5995 Vec2End = CandidateTypes[1].vector_end(); 5996 Vec2 != Vec2End; ++Vec2) { 5997 QualType ParamTypes[2]; 5998 ParamTypes[1] = *Vec2; 5999 // Add this built-in operator as a candidate (VQ is empty). 6000 ParamTypes[0] = S.Context.getLValueReferenceType(*Vec1); 6001 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 6002 /*IsAssigmentOperator=*/isEqualOp); 6003 6004 // Add this built-in operator as a candidate (VQ is 'volatile'). 6005 if (VisibleTypeConversionsQuals.hasVolatile()) { 6006 ParamTypes[0] = S.Context.getVolatileType(*Vec1); 6007 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 6008 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 6009 CandidateSet, 6010 /*IsAssigmentOperator=*/isEqualOp); 6011 } 6012 } 6013 } 6014 } 6015 6016 // C++ [over.built]p22: 6017 // 6018 // For every triple (L, VQ, R), where L is an integral type, VQ 6019 // is either volatile or empty, and R is a promoted integral 6020 // type, there exist candidate operator functions of the form 6021 // 6022 // VQ L& operator%=(VQ L&, R); 6023 // VQ L& operator<<=(VQ L&, R); 6024 // VQ L& operator>>=(VQ L&, R); 6025 // VQ L& operator&=(VQ L&, R); 6026 // VQ L& operator^=(VQ L&, R); 6027 // VQ L& operator|=(VQ L&, R); 6028 void addAssignmentIntegralOverloads() { 6029 if (!HasArithmeticOrEnumeralCandidateType) 6030 return; 6031 6032 for (unsigned Left = FirstIntegralType; Left < LastIntegralType; ++Left) { 6033 for (unsigned Right = FirstPromotedIntegralType; 6034 Right < LastPromotedIntegralType; ++Right) { 6035 QualType ParamTypes[2]; 6036 ParamTypes[1] = getArithmeticType(Right); 6037 6038 // Add this built-in operator as a candidate (VQ is empty). 6039 ParamTypes[0] = 6040 S.Context.getLValueReferenceType(getArithmeticType(Left)); 6041 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet); 6042 if (VisibleTypeConversionsQuals.hasVolatile()) { 6043 // Add this built-in operator as a candidate (VQ is 'volatile'). 6044 ParamTypes[0] = getArithmeticType(Left); 6045 ParamTypes[0] = S.Context.getVolatileType(ParamTypes[0]); 6046 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 6047 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 6048 CandidateSet); 6049 } 6050 } 6051 } 6052 } 6053 6054 // C++ [over.operator]p23: 6055 // 6056 // There also exist candidate operator functions of the form 6057 // 6058 // bool operator!(bool); 6059 // bool operator&&(bool, bool); 6060 // bool operator||(bool, bool); 6061 void addExclaimOverload() { 6062 QualType ParamTy = S.Context.BoolTy; 6063 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet, 6064 /*IsAssignmentOperator=*/false, 6065 /*NumContextualBoolArguments=*/1); 6066 } 6067 void addAmpAmpOrPipePipeOverload() { 6068 QualType ParamTypes[2] = { S.Context.BoolTy, S.Context.BoolTy }; 6069 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, CandidateSet, 6070 /*IsAssignmentOperator=*/false, 6071 /*NumContextualBoolArguments=*/2); 6072 } 6073 6074 // C++ [over.built]p13: 6075 // 6076 // For every cv-qualified or cv-unqualified object type T there 6077 // exist candidate operator functions of the form 6078 // 6079 // T* operator+(T*, ptrdiff_t); [ABOVE] 6080 // T& operator[](T*, ptrdiff_t); 6081 // T* operator-(T*, ptrdiff_t); [ABOVE] 6082 // T* operator+(ptrdiff_t, T*); [ABOVE] 6083 // T& operator[](ptrdiff_t, T*); 6084 void addSubscriptOverloads() { 6085 for (BuiltinCandidateTypeSet::iterator 6086 Ptr = CandidateTypes[0].pointer_begin(), 6087 PtrEnd = CandidateTypes[0].pointer_end(); 6088 Ptr != PtrEnd; ++Ptr) { 6089 QualType ParamTypes[2] = { *Ptr, S.Context.getPointerDiffType() }; 6090 QualType PointeeType = (*Ptr)->getPointeeType(); 6091 if (!PointeeType->isObjectType()) 6092 continue; 6093 6094 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 6095 6096 // T& operator[](T*, ptrdiff_t) 6097 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 6098 } 6099 6100 for (BuiltinCandidateTypeSet::iterator 6101 Ptr = CandidateTypes[1].pointer_begin(), 6102 PtrEnd = CandidateTypes[1].pointer_end(); 6103 Ptr != PtrEnd; ++Ptr) { 6104 QualType ParamTypes[2] = { S.Context.getPointerDiffType(), *Ptr }; 6105 QualType PointeeType = (*Ptr)->getPointeeType(); 6106 if (!PointeeType->isObjectType()) 6107 continue; 6108 6109 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 6110 6111 // T& operator[](ptrdiff_t, T*) 6112 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 6113 } 6114 } 6115 6116 // C++ [over.built]p11: 6117 // For every quintuple (C1, C2, T, CV1, CV2), where C2 is a class type, 6118 // C1 is the same type as C2 or is a derived class of C2, T is an object 6119 // type or a function type, and CV1 and CV2 are cv-qualifier-seqs, 6120 // there exist candidate operator functions of the form 6121 // 6122 // CV12 T& operator->*(CV1 C1*, CV2 T C2::*); 6123 // 6124 // where CV12 is the union of CV1 and CV2. 6125 void addArrowStarOverloads() { 6126 for (BuiltinCandidateTypeSet::iterator 6127 Ptr = CandidateTypes[0].pointer_begin(), 6128 PtrEnd = CandidateTypes[0].pointer_end(); 6129 Ptr != PtrEnd; ++Ptr) { 6130 QualType C1Ty = (*Ptr); 6131 QualType C1; 6132 QualifierCollector Q1; 6133 C1 = QualType(Q1.strip(C1Ty->getPointeeType()), 0); 6134 if (!isa<RecordType>(C1)) 6135 continue; 6136 // heuristic to reduce number of builtin candidates in the set. 6137 // Add volatile/restrict version only if there are conversions to a 6138 // volatile/restrict type. 6139 if (!VisibleTypeConversionsQuals.hasVolatile() && Q1.hasVolatile()) 6140 continue; 6141 if (!VisibleTypeConversionsQuals.hasRestrict() && Q1.hasRestrict()) 6142 continue; 6143 for (BuiltinCandidateTypeSet::iterator 6144 MemPtr = CandidateTypes[1].member_pointer_begin(), 6145 MemPtrEnd = CandidateTypes[1].member_pointer_end(); 6146 MemPtr != MemPtrEnd; ++MemPtr) { 6147 const MemberPointerType *mptr = cast<MemberPointerType>(*MemPtr); 6148 QualType C2 = QualType(mptr->getClass(), 0); 6149 C2 = C2.getUnqualifiedType(); 6150 if (C1 != C2 && !S.IsDerivedFrom(C1, C2)) 6151 break; 6152 QualType ParamTypes[2] = { *Ptr, *MemPtr }; 6153 // build CV12 T& 6154 QualType T = mptr->getPointeeType(); 6155 if (!VisibleTypeConversionsQuals.hasVolatile() && 6156 T.isVolatileQualified()) 6157 continue; 6158 if (!VisibleTypeConversionsQuals.hasRestrict() && 6159 T.isRestrictQualified()) 6160 continue; 6161 T = Q1.apply(S.Context, T); 6162 QualType ResultTy = S.Context.getLValueReferenceType(T); 6163 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 6164 } 6165 } 6166 } 6167 6168 // Note that we don't consider the first argument, since it has been 6169 // contextually converted to bool long ago. The candidates below are 6170 // therefore added as binary. 6171 // 6172 // C++ [over.built]p25: 6173 // For every type T, where T is a pointer, pointer-to-member, or scoped 6174 // enumeration type, there exist candidate operator functions of the form 6175 // 6176 // T operator?(bool, T, T); 6177 // 6178 void addConditionalOperatorOverloads() { 6179 /// Set of (canonical) types that we've already handled. 6180 llvm::SmallPtrSet<QualType, 8> AddedTypes; 6181 6182 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 6183 for (BuiltinCandidateTypeSet::iterator 6184 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 6185 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 6186 Ptr != PtrEnd; ++Ptr) { 6187 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 6188 continue; 6189 6190 QualType ParamTypes[2] = { *Ptr, *Ptr }; 6191 S.AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 6192 } 6193 6194 for (BuiltinCandidateTypeSet::iterator 6195 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 6196 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 6197 MemPtr != MemPtrEnd; ++MemPtr) { 6198 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 6199 continue; 6200 6201 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 6202 S.AddBuiltinCandidate(*MemPtr, ParamTypes, Args, 2, CandidateSet); 6203 } 6204 6205 if (S.getLangOptions().CPlusPlus0x) { 6206 for (BuiltinCandidateTypeSet::iterator 6207 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 6208 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 6209 Enum != EnumEnd; ++Enum) { 6210 if (!(*Enum)->getAs<EnumType>()->getDecl()->isScoped()) 6211 continue; 6212 6213 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 6214 continue; 6215 6216 QualType ParamTypes[2] = { *Enum, *Enum }; 6217 S.AddBuiltinCandidate(*Enum, ParamTypes, Args, 2, CandidateSet); 6218 } 6219 } 6220 } 6221 } 6222}; 6223 6224} // end anonymous namespace 6225 6226/// AddBuiltinOperatorCandidates - Add the appropriate built-in 6227/// operator overloads to the candidate set (C++ [over.built]), based 6228/// on the operator @p Op and the arguments given. For example, if the 6229/// operator is a binary '+', this routine might add "int 6230/// operator+(int, int)" to cover integer addition. 6231void 6232Sema::AddBuiltinOperatorCandidates(OverloadedOperatorKind Op, 6233 SourceLocation OpLoc, 6234 Expr **Args, unsigned NumArgs, 6235 OverloadCandidateSet& CandidateSet) { 6236 // Find all of the types that the arguments can convert to, but only 6237 // if the operator we're looking at has built-in operator candidates 6238 // that make use of these types. Also record whether we encounter non-record 6239 // candidate types or either arithmetic or enumeral candidate types. 6240 Qualifiers VisibleTypeConversionsQuals; 6241 VisibleTypeConversionsQuals.addConst(); 6242 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 6243 VisibleTypeConversionsQuals += CollectVRQualifiers(Context, Args[ArgIdx]); 6244 6245 bool HasNonRecordCandidateType = false; 6246 bool HasArithmeticOrEnumeralCandidateType = false; 6247 SmallVector<BuiltinCandidateTypeSet, 2> CandidateTypes; 6248 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6249 CandidateTypes.push_back(BuiltinCandidateTypeSet(*this)); 6250 CandidateTypes[ArgIdx].AddTypesConvertedFrom(Args[ArgIdx]->getType(), 6251 OpLoc, 6252 true, 6253 (Op == OO_Exclaim || 6254 Op == OO_AmpAmp || 6255 Op == OO_PipePipe), 6256 VisibleTypeConversionsQuals); 6257 HasNonRecordCandidateType = HasNonRecordCandidateType || 6258 CandidateTypes[ArgIdx].hasNonRecordTypes(); 6259 HasArithmeticOrEnumeralCandidateType = 6260 HasArithmeticOrEnumeralCandidateType || 6261 CandidateTypes[ArgIdx].hasArithmeticOrEnumeralTypes(); 6262 } 6263 6264 // Exit early when no non-record types have been added to the candidate set 6265 // for any of the arguments to the operator. 6266 if (!HasNonRecordCandidateType) 6267 return; 6268 6269 // Setup an object to manage the common state for building overloads. 6270 BuiltinOperatorOverloadBuilder OpBuilder(*this, Args, NumArgs, 6271 VisibleTypeConversionsQuals, 6272 HasArithmeticOrEnumeralCandidateType, 6273 CandidateTypes, CandidateSet); 6274 6275 // Dispatch over the operation to add in only those overloads which apply. 6276 switch (Op) { 6277 case OO_None: 6278 case NUM_OVERLOADED_OPERATORS: 6279 assert(false && "Expected an overloaded operator"); 6280 break; 6281 6282 case OO_New: 6283 case OO_Delete: 6284 case OO_Array_New: 6285 case OO_Array_Delete: 6286 case OO_Call: 6287 assert(false && "Special operators don't use AddBuiltinOperatorCandidates"); 6288 break; 6289 6290 case OO_Comma: 6291 case OO_Arrow: 6292 // C++ [over.match.oper]p3: 6293 // -- For the operator ',', the unary operator '&', or the 6294 // operator '->', the built-in candidates set is empty. 6295 break; 6296 6297 case OO_Plus: // '+' is either unary or binary 6298 if (NumArgs == 1) 6299 OpBuilder.addUnaryPlusPointerOverloads(); 6300 // Fall through. 6301 6302 case OO_Minus: // '-' is either unary or binary 6303 if (NumArgs == 1) { 6304 OpBuilder.addUnaryPlusOrMinusArithmeticOverloads(); 6305 } else { 6306 OpBuilder.addBinaryPlusOrMinusPointerOverloads(Op); 6307 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6308 } 6309 break; 6310 6311 case OO_Star: // '*' is either unary or binary 6312 if (NumArgs == 1) 6313 OpBuilder.addUnaryStarPointerOverloads(); 6314 else 6315 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6316 break; 6317 6318 case OO_Slash: 6319 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6320 break; 6321 6322 case OO_PlusPlus: 6323 case OO_MinusMinus: 6324 OpBuilder.addPlusPlusMinusMinusArithmeticOverloads(Op); 6325 OpBuilder.addPlusPlusMinusMinusPointerOverloads(); 6326 break; 6327 6328 case OO_EqualEqual: 6329 case OO_ExclaimEqual: 6330 OpBuilder.addEqualEqualOrNotEqualMemberPointerOverloads(); 6331 // Fall through. 6332 6333 case OO_Less: 6334 case OO_Greater: 6335 case OO_LessEqual: 6336 case OO_GreaterEqual: 6337 OpBuilder.addRelationalPointerOrEnumeralOverloads(); 6338 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/true); 6339 break; 6340 6341 case OO_Percent: 6342 case OO_Caret: 6343 case OO_Pipe: 6344 case OO_LessLess: 6345 case OO_GreaterGreater: 6346 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6347 break; 6348 6349 case OO_Amp: // '&' is either unary or binary 6350 if (NumArgs == 1) 6351 // C++ [over.match.oper]p3: 6352 // -- For the operator ',', the unary operator '&', or the 6353 // operator '->', the built-in candidates set is empty. 6354 break; 6355 6356 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6357 break; 6358 6359 case OO_Tilde: 6360 OpBuilder.addUnaryTildePromotedIntegralOverloads(); 6361 break; 6362 6363 case OO_Equal: 6364 OpBuilder.addAssignmentMemberPointerOrEnumeralOverloads(); 6365 // Fall through. 6366 6367 case OO_PlusEqual: 6368 case OO_MinusEqual: 6369 OpBuilder.addAssignmentPointerOverloads(Op == OO_Equal); 6370 // Fall through. 6371 6372 case OO_StarEqual: 6373 case OO_SlashEqual: 6374 OpBuilder.addAssignmentArithmeticOverloads(Op == OO_Equal); 6375 break; 6376 6377 case OO_PercentEqual: 6378 case OO_LessLessEqual: 6379 case OO_GreaterGreaterEqual: 6380 case OO_AmpEqual: 6381 case OO_CaretEqual: 6382 case OO_PipeEqual: 6383 OpBuilder.addAssignmentIntegralOverloads(); 6384 break; 6385 6386 case OO_Exclaim: 6387 OpBuilder.addExclaimOverload(); 6388 break; 6389 6390 case OO_AmpAmp: 6391 case OO_PipePipe: 6392 OpBuilder.addAmpAmpOrPipePipeOverload(); 6393 break; 6394 6395 case OO_Subscript: 6396 OpBuilder.addSubscriptOverloads(); 6397 break; 6398 6399 case OO_ArrowStar: 6400 OpBuilder.addArrowStarOverloads(); 6401 break; 6402 6403 case OO_Conditional: 6404 OpBuilder.addConditionalOperatorOverloads(); 6405 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6406 break; 6407 } 6408} 6409 6410/// \brief Add function candidates found via argument-dependent lookup 6411/// to the set of overloading candidates. 6412/// 6413/// This routine performs argument-dependent name lookup based on the 6414/// given function name (which may also be an operator name) and adds 6415/// all of the overload candidates found by ADL to the overload 6416/// candidate set (C++ [basic.lookup.argdep]). 6417void 6418Sema::AddArgumentDependentLookupCandidates(DeclarationName Name, 6419 bool Operator, 6420 Expr **Args, unsigned NumArgs, 6421 TemplateArgumentListInfo *ExplicitTemplateArgs, 6422 OverloadCandidateSet& CandidateSet, 6423 bool PartialOverloading, 6424 bool StdNamespaceIsAssociated) { 6425 ADLResult Fns; 6426 6427 // FIXME: This approach for uniquing ADL results (and removing 6428 // redundant candidates from the set) relies on pointer-equality, 6429 // which means we need to key off the canonical decl. However, 6430 // always going back to the canonical decl might not get us the 6431 // right set of default arguments. What default arguments are 6432 // we supposed to consider on ADL candidates, anyway? 6433 6434 // FIXME: Pass in the explicit template arguments? 6435 ArgumentDependentLookup(Name, Operator, Args, NumArgs, Fns, 6436 StdNamespaceIsAssociated); 6437 6438 // Erase all of the candidates we already knew about. 6439 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(), 6440 CandEnd = CandidateSet.end(); 6441 Cand != CandEnd; ++Cand) 6442 if (Cand->Function) { 6443 Fns.erase(Cand->Function); 6444 if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate()) 6445 Fns.erase(FunTmpl); 6446 } 6447 6448 // For each of the ADL candidates we found, add it to the overload 6449 // set. 6450 for (ADLResult::iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) { 6451 DeclAccessPair FoundDecl = DeclAccessPair::make(*I, AS_none); 6452 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) { 6453 if (ExplicitTemplateArgs) 6454 continue; 6455 6456 AddOverloadCandidate(FD, FoundDecl, Args, NumArgs, CandidateSet, 6457 false, PartialOverloading); 6458 } else 6459 AddTemplateOverloadCandidate(cast<FunctionTemplateDecl>(*I), 6460 FoundDecl, ExplicitTemplateArgs, 6461 Args, NumArgs, CandidateSet); 6462 } 6463} 6464 6465/// isBetterOverloadCandidate - Determines whether the first overload 6466/// candidate is a better candidate than the second (C++ 13.3.3p1). 6467bool 6468isBetterOverloadCandidate(Sema &S, 6469 const OverloadCandidate &Cand1, 6470 const OverloadCandidate &Cand2, 6471 SourceLocation Loc, 6472 bool UserDefinedConversion) { 6473 // Define viable functions to be better candidates than non-viable 6474 // functions. 6475 if (!Cand2.Viable) 6476 return Cand1.Viable; 6477 else if (!Cand1.Viable) 6478 return false; 6479 6480 // C++ [over.match.best]p1: 6481 // 6482 // -- if F is a static member function, ICS1(F) is defined such 6483 // that ICS1(F) is neither better nor worse than ICS1(G) for 6484 // any function G, and, symmetrically, ICS1(G) is neither 6485 // better nor worse than ICS1(F). 6486 unsigned StartArg = 0; 6487 if (Cand1.IgnoreObjectArgument || Cand2.IgnoreObjectArgument) 6488 StartArg = 1; 6489 6490 // C++ [over.match.best]p1: 6491 // A viable function F1 is defined to be a better function than another 6492 // viable function F2 if for all arguments i, ICSi(F1) is not a worse 6493 // conversion sequence than ICSi(F2), and then... 6494 unsigned NumArgs = Cand1.Conversions.size(); 6495 assert(Cand2.Conversions.size() == NumArgs && "Overload candidate mismatch"); 6496 bool HasBetterConversion = false; 6497 for (unsigned ArgIdx = StartArg; ArgIdx < NumArgs; ++ArgIdx) { 6498 switch (CompareImplicitConversionSequences(S, 6499 Cand1.Conversions[ArgIdx], 6500 Cand2.Conversions[ArgIdx])) { 6501 case ImplicitConversionSequence::Better: 6502 // Cand1 has a better conversion sequence. 6503 HasBetterConversion = true; 6504 break; 6505 6506 case ImplicitConversionSequence::Worse: 6507 // Cand1 can't be better than Cand2. 6508 return false; 6509 6510 case ImplicitConversionSequence::Indistinguishable: 6511 // Do nothing. 6512 break; 6513 } 6514 } 6515 6516 // -- for some argument j, ICSj(F1) is a better conversion sequence than 6517 // ICSj(F2), or, if not that, 6518 if (HasBetterConversion) 6519 return true; 6520 6521 // - F1 is a non-template function and F2 is a function template 6522 // specialization, or, if not that, 6523 if ((!Cand1.Function || !Cand1.Function->getPrimaryTemplate()) && 6524 Cand2.Function && Cand2.Function->getPrimaryTemplate()) 6525 return true; 6526 6527 // -- F1 and F2 are function template specializations, and the function 6528 // template for F1 is more specialized than the template for F2 6529 // according to the partial ordering rules described in 14.5.5.2, or, 6530 // if not that, 6531 if (Cand1.Function && Cand1.Function->getPrimaryTemplate() && 6532 Cand2.Function && Cand2.Function->getPrimaryTemplate()) { 6533 if (FunctionTemplateDecl *BetterTemplate 6534 = S.getMoreSpecializedTemplate(Cand1.Function->getPrimaryTemplate(), 6535 Cand2.Function->getPrimaryTemplate(), 6536 Loc, 6537 isa<CXXConversionDecl>(Cand1.Function)? TPOC_Conversion 6538 : TPOC_Call, 6539 Cand1.ExplicitCallArguments)) 6540 return BetterTemplate == Cand1.Function->getPrimaryTemplate(); 6541 } 6542 6543 // -- the context is an initialization by user-defined conversion 6544 // (see 8.5, 13.3.1.5) and the standard conversion sequence 6545 // from the return type of F1 to the destination type (i.e., 6546 // the type of the entity being initialized) is a better 6547 // conversion sequence than the standard conversion sequence 6548 // from the return type of F2 to the destination type. 6549 if (UserDefinedConversion && Cand1.Function && Cand2.Function && 6550 isa<CXXConversionDecl>(Cand1.Function) && 6551 isa<CXXConversionDecl>(Cand2.Function)) { 6552 switch (CompareStandardConversionSequences(S, 6553 Cand1.FinalConversion, 6554 Cand2.FinalConversion)) { 6555 case ImplicitConversionSequence::Better: 6556 // Cand1 has a better conversion sequence. 6557 return true; 6558 6559 case ImplicitConversionSequence::Worse: 6560 // Cand1 can't be better than Cand2. 6561 return false; 6562 6563 case ImplicitConversionSequence::Indistinguishable: 6564 // Do nothing 6565 break; 6566 } 6567 } 6568 6569 return false; 6570} 6571 6572/// \brief Computes the best viable function (C++ 13.3.3) 6573/// within an overload candidate set. 6574/// 6575/// \param CandidateSet the set of candidate functions. 6576/// 6577/// \param Loc the location of the function name (or operator symbol) for 6578/// which overload resolution occurs. 6579/// 6580/// \param Best f overload resolution was successful or found a deleted 6581/// function, Best points to the candidate function found. 6582/// 6583/// \returns The result of overload resolution. 6584OverloadingResult 6585OverloadCandidateSet::BestViableFunction(Sema &S, SourceLocation Loc, 6586 iterator &Best, 6587 bool UserDefinedConversion) { 6588 // Find the best viable function. 6589 Best = end(); 6590 for (iterator Cand = begin(); Cand != end(); ++Cand) { 6591 if (Cand->Viable) 6592 if (Best == end() || isBetterOverloadCandidate(S, *Cand, *Best, Loc, 6593 UserDefinedConversion)) 6594 Best = Cand; 6595 } 6596 6597 // If we didn't find any viable functions, abort. 6598 if (Best == end()) 6599 return OR_No_Viable_Function; 6600 6601 // Make sure that this function is better than every other viable 6602 // function. If not, we have an ambiguity. 6603 for (iterator Cand = begin(); Cand != end(); ++Cand) { 6604 if (Cand->Viable && 6605 Cand != Best && 6606 !isBetterOverloadCandidate(S, *Best, *Cand, Loc, 6607 UserDefinedConversion)) { 6608 Best = end(); 6609 return OR_Ambiguous; 6610 } 6611 } 6612 6613 // Best is the best viable function. 6614 if (Best->Function && 6615 (Best->Function->isDeleted() || 6616 S.isFunctionConsideredUnavailable(Best->Function))) 6617 return OR_Deleted; 6618 6619 return OR_Success; 6620} 6621 6622namespace { 6623 6624enum OverloadCandidateKind { 6625 oc_function, 6626 oc_method, 6627 oc_constructor, 6628 oc_function_template, 6629 oc_method_template, 6630 oc_constructor_template, 6631 oc_implicit_default_constructor, 6632 oc_implicit_copy_constructor, 6633 oc_implicit_move_constructor, 6634 oc_implicit_copy_assignment, 6635 oc_implicit_move_assignment, 6636 oc_implicit_inherited_constructor 6637}; 6638 6639OverloadCandidateKind ClassifyOverloadCandidate(Sema &S, 6640 FunctionDecl *Fn, 6641 std::string &Description) { 6642 bool isTemplate = false; 6643 6644 if (FunctionTemplateDecl *FunTmpl = Fn->getPrimaryTemplate()) { 6645 isTemplate = true; 6646 Description = S.getTemplateArgumentBindingsText( 6647 FunTmpl->getTemplateParameters(), *Fn->getTemplateSpecializationArgs()); 6648 } 6649 6650 if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn)) { 6651 if (!Ctor->isImplicit()) 6652 return isTemplate ? oc_constructor_template : oc_constructor; 6653 6654 if (Ctor->getInheritedConstructor()) 6655 return oc_implicit_inherited_constructor; 6656 6657 if (Ctor->isDefaultConstructor()) 6658 return oc_implicit_default_constructor; 6659 6660 if (Ctor->isMoveConstructor()) 6661 return oc_implicit_move_constructor; 6662 6663 assert(Ctor->isCopyConstructor() && 6664 "unexpected sort of implicit constructor"); 6665 return oc_implicit_copy_constructor; 6666 } 6667 6668 if (CXXMethodDecl *Meth = dyn_cast<CXXMethodDecl>(Fn)) { 6669 // This actually gets spelled 'candidate function' for now, but 6670 // it doesn't hurt to split it out. 6671 if (!Meth->isImplicit()) 6672 return isTemplate ? oc_method_template : oc_method; 6673 6674 if (Meth->isMoveAssignmentOperator()) 6675 return oc_implicit_move_assignment; 6676 6677 assert(Meth->isCopyAssignmentOperator() 6678 && "implicit method is not copy assignment operator?"); 6679 return oc_implicit_copy_assignment; 6680 } 6681 6682 return isTemplate ? oc_function_template : oc_function; 6683} 6684 6685void MaybeEmitInheritedConstructorNote(Sema &S, FunctionDecl *Fn) { 6686 const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn); 6687 if (!Ctor) return; 6688 6689 Ctor = Ctor->getInheritedConstructor(); 6690 if (!Ctor) return; 6691 6692 S.Diag(Ctor->getLocation(), diag::note_ovl_candidate_inherited_constructor); 6693} 6694 6695} // end anonymous namespace 6696 6697// Notes the location of an overload candidate. 6698void Sema::NoteOverloadCandidate(FunctionDecl *Fn) { 6699 std::string FnDesc; 6700 OverloadCandidateKind K = ClassifyOverloadCandidate(*this, Fn, FnDesc); 6701 Diag(Fn->getLocation(), diag::note_ovl_candidate) 6702 << (unsigned) K << FnDesc; 6703 MaybeEmitInheritedConstructorNote(*this, Fn); 6704} 6705 6706//Notes the location of all overload candidates designated through 6707// OverloadedExpr 6708void Sema::NoteAllOverloadCandidates(Expr* OverloadedExpr) { 6709 assert(OverloadedExpr->getType() == Context.OverloadTy); 6710 6711 OverloadExpr::FindResult Ovl = OverloadExpr::find(OverloadedExpr); 6712 OverloadExpr *OvlExpr = Ovl.Expression; 6713 6714 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 6715 IEnd = OvlExpr->decls_end(); 6716 I != IEnd; ++I) { 6717 if (FunctionTemplateDecl *FunTmpl = 6718 dyn_cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()) ) { 6719 NoteOverloadCandidate(FunTmpl->getTemplatedDecl()); 6720 } else if (FunctionDecl *Fun 6721 = dyn_cast<FunctionDecl>((*I)->getUnderlyingDecl()) ) { 6722 NoteOverloadCandidate(Fun); 6723 } 6724 } 6725} 6726 6727/// Diagnoses an ambiguous conversion. The partial diagnostic is the 6728/// "lead" diagnostic; it will be given two arguments, the source and 6729/// target types of the conversion. 6730void ImplicitConversionSequence::DiagnoseAmbiguousConversion( 6731 Sema &S, 6732 SourceLocation CaretLoc, 6733 const PartialDiagnostic &PDiag) const { 6734 S.Diag(CaretLoc, PDiag) 6735 << Ambiguous.getFromType() << Ambiguous.getToType(); 6736 for (AmbiguousConversionSequence::const_iterator 6737 I = Ambiguous.begin(), E = Ambiguous.end(); I != E; ++I) { 6738 S.NoteOverloadCandidate(*I); 6739 } 6740} 6741 6742namespace { 6743 6744void DiagnoseBadConversion(Sema &S, OverloadCandidate *Cand, unsigned I) { 6745 const ImplicitConversionSequence &Conv = Cand->Conversions[I]; 6746 assert(Conv.isBad()); 6747 assert(Cand->Function && "for now, candidate must be a function"); 6748 FunctionDecl *Fn = Cand->Function; 6749 6750 // There's a conversion slot for the object argument if this is a 6751 // non-constructor method. Note that 'I' corresponds the 6752 // conversion-slot index. 6753 bool isObjectArgument = false; 6754 if (isa<CXXMethodDecl>(Fn) && !isa<CXXConstructorDecl>(Fn)) { 6755 if (I == 0) 6756 isObjectArgument = true; 6757 else 6758 I--; 6759 } 6760 6761 std::string FnDesc; 6762 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 6763 6764 Expr *FromExpr = Conv.Bad.FromExpr; 6765 QualType FromTy = Conv.Bad.getFromType(); 6766 QualType ToTy = Conv.Bad.getToType(); 6767 6768 if (FromTy == S.Context.OverloadTy) { 6769 assert(FromExpr && "overload set argument came from implicit argument?"); 6770 Expr *E = FromExpr->IgnoreParens(); 6771 if (isa<UnaryOperator>(E)) 6772 E = cast<UnaryOperator>(E)->getSubExpr()->IgnoreParens(); 6773 DeclarationName Name = cast<OverloadExpr>(E)->getName(); 6774 6775 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_overload) 6776 << (unsigned) FnKind << FnDesc 6777 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6778 << ToTy << Name << I+1; 6779 MaybeEmitInheritedConstructorNote(S, Fn); 6780 return; 6781 } 6782 6783 // Do some hand-waving analysis to see if the non-viability is due 6784 // to a qualifier mismatch. 6785 CanQualType CFromTy = S.Context.getCanonicalType(FromTy); 6786 CanQualType CToTy = S.Context.getCanonicalType(ToTy); 6787 if (CanQual<ReferenceType> RT = CToTy->getAs<ReferenceType>()) 6788 CToTy = RT->getPointeeType(); 6789 else { 6790 // TODO: detect and diagnose the full richness of const mismatches. 6791 if (CanQual<PointerType> FromPT = CFromTy->getAs<PointerType>()) 6792 if (CanQual<PointerType> ToPT = CToTy->getAs<PointerType>()) 6793 CFromTy = FromPT->getPointeeType(), CToTy = ToPT->getPointeeType(); 6794 } 6795 6796 if (CToTy.getUnqualifiedType() == CFromTy.getUnqualifiedType() && 6797 !CToTy.isAtLeastAsQualifiedAs(CFromTy)) { 6798 // It is dumb that we have to do this here. 6799 while (isa<ArrayType>(CFromTy)) 6800 CFromTy = CFromTy->getAs<ArrayType>()->getElementType(); 6801 while (isa<ArrayType>(CToTy)) 6802 CToTy = CFromTy->getAs<ArrayType>()->getElementType(); 6803 6804 Qualifiers FromQs = CFromTy.getQualifiers(); 6805 Qualifiers ToQs = CToTy.getQualifiers(); 6806 6807 if (FromQs.getAddressSpace() != ToQs.getAddressSpace()) { 6808 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_addrspace) 6809 << (unsigned) FnKind << FnDesc 6810 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6811 << FromTy 6812 << FromQs.getAddressSpace() << ToQs.getAddressSpace() 6813 << (unsigned) isObjectArgument << I+1; 6814 MaybeEmitInheritedConstructorNote(S, Fn); 6815 return; 6816 } 6817 6818 if (FromQs.getObjCLifetime() != ToQs.getObjCLifetime()) { 6819 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_ownership) 6820 << (unsigned) FnKind << FnDesc 6821 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6822 << FromTy 6823 << FromQs.getObjCLifetime() << ToQs.getObjCLifetime() 6824 << (unsigned) isObjectArgument << I+1; 6825 MaybeEmitInheritedConstructorNote(S, Fn); 6826 return; 6827 } 6828 6829 if (FromQs.getObjCGCAttr() != ToQs.getObjCGCAttr()) { 6830 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_gc) 6831 << (unsigned) FnKind << FnDesc 6832 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6833 << FromTy 6834 << FromQs.getObjCGCAttr() << ToQs.getObjCGCAttr() 6835 << (unsigned) isObjectArgument << I+1; 6836 MaybeEmitInheritedConstructorNote(S, Fn); 6837 return; 6838 } 6839 6840 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 6841 assert(CVR && "unexpected qualifiers mismatch"); 6842 6843 if (isObjectArgument) { 6844 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr_this) 6845 << (unsigned) FnKind << FnDesc 6846 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6847 << FromTy << (CVR - 1); 6848 } else { 6849 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr) 6850 << (unsigned) FnKind << FnDesc 6851 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6852 << FromTy << (CVR - 1) << I+1; 6853 } 6854 MaybeEmitInheritedConstructorNote(S, Fn); 6855 return; 6856 } 6857 6858 // Diagnose references or pointers to incomplete types differently, 6859 // since it's far from impossible that the incompleteness triggered 6860 // the failure. 6861 QualType TempFromTy = FromTy.getNonReferenceType(); 6862 if (const PointerType *PTy = TempFromTy->getAs<PointerType>()) 6863 TempFromTy = PTy->getPointeeType(); 6864 if (TempFromTy->isIncompleteType()) { 6865 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv_incomplete) 6866 << (unsigned) FnKind << FnDesc 6867 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6868 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 6869 MaybeEmitInheritedConstructorNote(S, Fn); 6870 return; 6871 } 6872 6873 // Diagnose base -> derived pointer conversions. 6874 unsigned BaseToDerivedConversion = 0; 6875 if (const PointerType *FromPtrTy = FromTy->getAs<PointerType>()) { 6876 if (const PointerType *ToPtrTy = ToTy->getAs<PointerType>()) { 6877 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 6878 FromPtrTy->getPointeeType()) && 6879 !FromPtrTy->getPointeeType()->isIncompleteType() && 6880 !ToPtrTy->getPointeeType()->isIncompleteType() && 6881 S.IsDerivedFrom(ToPtrTy->getPointeeType(), 6882 FromPtrTy->getPointeeType())) 6883 BaseToDerivedConversion = 1; 6884 } 6885 } else if (const ObjCObjectPointerType *FromPtrTy 6886 = FromTy->getAs<ObjCObjectPointerType>()) { 6887 if (const ObjCObjectPointerType *ToPtrTy 6888 = ToTy->getAs<ObjCObjectPointerType>()) 6889 if (const ObjCInterfaceDecl *FromIface = FromPtrTy->getInterfaceDecl()) 6890 if (const ObjCInterfaceDecl *ToIface = ToPtrTy->getInterfaceDecl()) 6891 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 6892 FromPtrTy->getPointeeType()) && 6893 FromIface->isSuperClassOf(ToIface)) 6894 BaseToDerivedConversion = 2; 6895 } else if (const ReferenceType *ToRefTy = ToTy->getAs<ReferenceType>()) { 6896 if (ToRefTy->getPointeeType().isAtLeastAsQualifiedAs(FromTy) && 6897 !FromTy->isIncompleteType() && 6898 !ToRefTy->getPointeeType()->isIncompleteType() && 6899 S.IsDerivedFrom(ToRefTy->getPointeeType(), FromTy)) 6900 BaseToDerivedConversion = 3; 6901 } 6902 6903 if (BaseToDerivedConversion) { 6904 S.Diag(Fn->getLocation(), 6905 diag::note_ovl_candidate_bad_base_to_derived_conv) 6906 << (unsigned) FnKind << FnDesc 6907 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6908 << (BaseToDerivedConversion - 1) 6909 << FromTy << ToTy << I+1; 6910 MaybeEmitInheritedConstructorNote(S, Fn); 6911 return; 6912 } 6913 6914 if (isa<ObjCObjectPointerType>(CFromTy) && 6915 isa<PointerType>(CToTy)) { 6916 Qualifiers FromQs = CFromTy.getQualifiers(); 6917 Qualifiers ToQs = CToTy.getQualifiers(); 6918 if (FromQs.getObjCLifetime() != ToQs.getObjCLifetime()) { 6919 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_arc_conv) 6920 << (unsigned) FnKind << FnDesc 6921 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6922 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 6923 MaybeEmitInheritedConstructorNote(S, Fn); 6924 return; 6925 } 6926 } 6927 6928 // Emit the generic diagnostic and, optionally, add the hints to it. 6929 PartialDiagnostic FDiag = S.PDiag(diag::note_ovl_candidate_bad_conv); 6930 FDiag << (unsigned) FnKind << FnDesc 6931 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6932 << FromTy << ToTy << (unsigned) isObjectArgument << I + 1 6933 << (unsigned) (Cand->Fix.Kind); 6934 6935 // If we can fix the conversion, suggest the FixIts. 6936 for (SmallVector<FixItHint, 1>::iterator 6937 HI = Cand->Fix.Hints.begin(), HE = Cand->Fix.Hints.end(); 6938 HI != HE; ++HI) 6939 FDiag << *HI; 6940 S.Diag(Fn->getLocation(), FDiag); 6941 6942 MaybeEmitInheritedConstructorNote(S, Fn); 6943} 6944 6945void DiagnoseArityMismatch(Sema &S, OverloadCandidate *Cand, 6946 unsigned NumFormalArgs) { 6947 // TODO: treat calls to a missing default constructor as a special case 6948 6949 FunctionDecl *Fn = Cand->Function; 6950 const FunctionProtoType *FnTy = Fn->getType()->getAs<FunctionProtoType>(); 6951 6952 unsigned MinParams = Fn->getMinRequiredArguments(); 6953 6954 // With invalid overloaded operators, it's possible that we think we 6955 // have an arity mismatch when it fact it looks like we have the 6956 // right number of arguments, because only overloaded operators have 6957 // the weird behavior of overloading member and non-member functions. 6958 // Just don't report anything. 6959 if (Fn->isInvalidDecl() && 6960 Fn->getDeclName().getNameKind() == DeclarationName::CXXOperatorName) 6961 return; 6962 6963 // at least / at most / exactly 6964 unsigned mode, modeCount; 6965 if (NumFormalArgs < MinParams) { 6966 assert((Cand->FailureKind == ovl_fail_too_few_arguments) || 6967 (Cand->FailureKind == ovl_fail_bad_deduction && 6968 Cand->DeductionFailure.Result == Sema::TDK_TooFewArguments)); 6969 if (MinParams != FnTy->getNumArgs() || 6970 FnTy->isVariadic() || FnTy->isTemplateVariadic()) 6971 mode = 0; // "at least" 6972 else 6973 mode = 2; // "exactly" 6974 modeCount = MinParams; 6975 } else { 6976 assert((Cand->FailureKind == ovl_fail_too_many_arguments) || 6977 (Cand->FailureKind == ovl_fail_bad_deduction && 6978 Cand->DeductionFailure.Result == Sema::TDK_TooManyArguments)); 6979 if (MinParams != FnTy->getNumArgs()) 6980 mode = 1; // "at most" 6981 else 6982 mode = 2; // "exactly" 6983 modeCount = FnTy->getNumArgs(); 6984 } 6985 6986 std::string Description; 6987 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, Description); 6988 6989 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity) 6990 << (unsigned) FnKind << (Fn->getDescribedFunctionTemplate() != 0) << mode 6991 << modeCount << NumFormalArgs; 6992 MaybeEmitInheritedConstructorNote(S, Fn); 6993} 6994 6995/// Diagnose a failed template-argument deduction. 6996void DiagnoseBadDeduction(Sema &S, OverloadCandidate *Cand, 6997 Expr **Args, unsigned NumArgs) { 6998 FunctionDecl *Fn = Cand->Function; // pattern 6999 7000 TemplateParameter Param = Cand->DeductionFailure.getTemplateParameter(); 7001 NamedDecl *ParamD; 7002 (ParamD = Param.dyn_cast<TemplateTypeParmDecl*>()) || 7003 (ParamD = Param.dyn_cast<NonTypeTemplateParmDecl*>()) || 7004 (ParamD = Param.dyn_cast<TemplateTemplateParmDecl*>()); 7005 switch (Cand->DeductionFailure.Result) { 7006 case Sema::TDK_Success: 7007 llvm_unreachable("TDK_success while diagnosing bad deduction"); 7008 7009 case Sema::TDK_Incomplete: { 7010 assert(ParamD && "no parameter found for incomplete deduction result"); 7011 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_incomplete_deduction) 7012 << ParamD->getDeclName(); 7013 MaybeEmitInheritedConstructorNote(S, Fn); 7014 return; 7015 } 7016 7017 case Sema::TDK_Underqualified: { 7018 assert(ParamD && "no parameter found for bad qualifiers deduction result"); 7019 TemplateTypeParmDecl *TParam = cast<TemplateTypeParmDecl>(ParamD); 7020 7021 QualType Param = Cand->DeductionFailure.getFirstArg()->getAsType(); 7022 7023 // Param will have been canonicalized, but it should just be a 7024 // qualified version of ParamD, so move the qualifiers to that. 7025 QualifierCollector Qs; 7026 Qs.strip(Param); 7027 QualType NonCanonParam = Qs.apply(S.Context, TParam->getTypeForDecl()); 7028 assert(S.Context.hasSameType(Param, NonCanonParam)); 7029 7030 // Arg has also been canonicalized, but there's nothing we can do 7031 // about that. It also doesn't matter as much, because it won't 7032 // have any template parameters in it (because deduction isn't 7033 // done on dependent types). 7034 QualType Arg = Cand->DeductionFailure.getSecondArg()->getAsType(); 7035 7036 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_underqualified) 7037 << ParamD->getDeclName() << Arg << NonCanonParam; 7038 MaybeEmitInheritedConstructorNote(S, Fn); 7039 return; 7040 } 7041 7042 case Sema::TDK_Inconsistent: { 7043 assert(ParamD && "no parameter found for inconsistent deduction result"); 7044 int which = 0; 7045 if (isa<TemplateTypeParmDecl>(ParamD)) 7046 which = 0; 7047 else if (isa<NonTypeTemplateParmDecl>(ParamD)) 7048 which = 1; 7049 else { 7050 which = 2; 7051 } 7052 7053 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_inconsistent_deduction) 7054 << which << ParamD->getDeclName() 7055 << *Cand->DeductionFailure.getFirstArg() 7056 << *Cand->DeductionFailure.getSecondArg(); 7057 MaybeEmitInheritedConstructorNote(S, Fn); 7058 return; 7059 } 7060 7061 case Sema::TDK_InvalidExplicitArguments: 7062 assert(ParamD && "no parameter found for invalid explicit arguments"); 7063 if (ParamD->getDeclName()) 7064 S.Diag(Fn->getLocation(), 7065 diag::note_ovl_candidate_explicit_arg_mismatch_named) 7066 << ParamD->getDeclName(); 7067 else { 7068 int index = 0; 7069 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ParamD)) 7070 index = TTP->getIndex(); 7071 else if (NonTypeTemplateParmDecl *NTTP 7072 = dyn_cast<NonTypeTemplateParmDecl>(ParamD)) 7073 index = NTTP->getIndex(); 7074 else 7075 index = cast<TemplateTemplateParmDecl>(ParamD)->getIndex(); 7076 S.Diag(Fn->getLocation(), 7077 diag::note_ovl_candidate_explicit_arg_mismatch_unnamed) 7078 << (index + 1); 7079 } 7080 MaybeEmitInheritedConstructorNote(S, Fn); 7081 return; 7082 7083 case Sema::TDK_TooManyArguments: 7084 case Sema::TDK_TooFewArguments: 7085 DiagnoseArityMismatch(S, Cand, NumArgs); 7086 return; 7087 7088 case Sema::TDK_InstantiationDepth: 7089 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_instantiation_depth); 7090 MaybeEmitInheritedConstructorNote(S, Fn); 7091 return; 7092 7093 case Sema::TDK_SubstitutionFailure: { 7094 std::string ArgString; 7095 if (TemplateArgumentList *Args 7096 = Cand->DeductionFailure.getTemplateArgumentList()) 7097 ArgString = S.getTemplateArgumentBindingsText( 7098 Fn->getDescribedFunctionTemplate()->getTemplateParameters(), 7099 *Args); 7100 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_substitution_failure) 7101 << ArgString; 7102 MaybeEmitInheritedConstructorNote(S, Fn); 7103 return; 7104 } 7105 7106 // TODO: diagnose these individually, then kill off 7107 // note_ovl_candidate_bad_deduction, which is uselessly vague. 7108 case Sema::TDK_NonDeducedMismatch: 7109 case Sema::TDK_FailedOverloadResolution: 7110 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_deduction); 7111 MaybeEmitInheritedConstructorNote(S, Fn); 7112 return; 7113 } 7114} 7115 7116/// Generates a 'note' diagnostic for an overload candidate. We've 7117/// already generated a primary error at the call site. 7118/// 7119/// It really does need to be a single diagnostic with its caret 7120/// pointed at the candidate declaration. Yes, this creates some 7121/// major challenges of technical writing. Yes, this makes pointing 7122/// out problems with specific arguments quite awkward. It's still 7123/// better than generating twenty screens of text for every failed 7124/// overload. 7125/// 7126/// It would be great to be able to express per-candidate problems 7127/// more richly for those diagnostic clients that cared, but we'd 7128/// still have to be just as careful with the default diagnostics. 7129void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand, 7130 Expr **Args, unsigned NumArgs) { 7131 FunctionDecl *Fn = Cand->Function; 7132 7133 // Note deleted candidates, but only if they're viable. 7134 if (Cand->Viable && (Fn->isDeleted() || 7135 S.isFunctionConsideredUnavailable(Fn))) { 7136 std::string FnDesc; 7137 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 7138 7139 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_deleted) 7140 << FnKind << FnDesc << Fn->isDeleted(); 7141 MaybeEmitInheritedConstructorNote(S, Fn); 7142 return; 7143 } 7144 7145 // We don't really have anything else to say about viable candidates. 7146 if (Cand->Viable) { 7147 S.NoteOverloadCandidate(Fn); 7148 return; 7149 } 7150 7151 switch (Cand->FailureKind) { 7152 case ovl_fail_too_many_arguments: 7153 case ovl_fail_too_few_arguments: 7154 return DiagnoseArityMismatch(S, Cand, NumArgs); 7155 7156 case ovl_fail_bad_deduction: 7157 return DiagnoseBadDeduction(S, Cand, Args, NumArgs); 7158 7159 case ovl_fail_trivial_conversion: 7160 case ovl_fail_bad_final_conversion: 7161 case ovl_fail_final_conversion_not_exact: 7162 return S.NoteOverloadCandidate(Fn); 7163 7164 case ovl_fail_bad_conversion: { 7165 unsigned I = (Cand->IgnoreObjectArgument ? 1 : 0); 7166 for (unsigned N = Cand->Conversions.size(); I != N; ++I) 7167 if (Cand->Conversions[I].isBad()) 7168 return DiagnoseBadConversion(S, Cand, I); 7169 7170 // FIXME: this currently happens when we're called from SemaInit 7171 // when user-conversion overload fails. Figure out how to handle 7172 // those conditions and diagnose them well. 7173 return S.NoteOverloadCandidate(Fn); 7174 } 7175 } 7176} 7177 7178void NoteSurrogateCandidate(Sema &S, OverloadCandidate *Cand) { 7179 // Desugar the type of the surrogate down to a function type, 7180 // retaining as many typedefs as possible while still showing 7181 // the function type (and, therefore, its parameter types). 7182 QualType FnType = Cand->Surrogate->getConversionType(); 7183 bool isLValueReference = false; 7184 bool isRValueReference = false; 7185 bool isPointer = false; 7186 if (const LValueReferenceType *FnTypeRef = 7187 FnType->getAs<LValueReferenceType>()) { 7188 FnType = FnTypeRef->getPointeeType(); 7189 isLValueReference = true; 7190 } else if (const RValueReferenceType *FnTypeRef = 7191 FnType->getAs<RValueReferenceType>()) { 7192 FnType = FnTypeRef->getPointeeType(); 7193 isRValueReference = true; 7194 } 7195 if (const PointerType *FnTypePtr = FnType->getAs<PointerType>()) { 7196 FnType = FnTypePtr->getPointeeType(); 7197 isPointer = true; 7198 } 7199 // Desugar down to a function type. 7200 FnType = QualType(FnType->getAs<FunctionType>(), 0); 7201 // Reconstruct the pointer/reference as appropriate. 7202 if (isPointer) FnType = S.Context.getPointerType(FnType); 7203 if (isRValueReference) FnType = S.Context.getRValueReferenceType(FnType); 7204 if (isLValueReference) FnType = S.Context.getLValueReferenceType(FnType); 7205 7206 S.Diag(Cand->Surrogate->getLocation(), diag::note_ovl_surrogate_cand) 7207 << FnType; 7208 MaybeEmitInheritedConstructorNote(S, Cand->Surrogate); 7209} 7210 7211void NoteBuiltinOperatorCandidate(Sema &S, 7212 const char *Opc, 7213 SourceLocation OpLoc, 7214 OverloadCandidate *Cand) { 7215 assert(Cand->Conversions.size() <= 2 && "builtin operator is not binary"); 7216 std::string TypeStr("operator"); 7217 TypeStr += Opc; 7218 TypeStr += "("; 7219 TypeStr += Cand->BuiltinTypes.ParamTypes[0].getAsString(); 7220 if (Cand->Conversions.size() == 1) { 7221 TypeStr += ")"; 7222 S.Diag(OpLoc, diag::note_ovl_builtin_unary_candidate) << TypeStr; 7223 } else { 7224 TypeStr += ", "; 7225 TypeStr += Cand->BuiltinTypes.ParamTypes[1].getAsString(); 7226 TypeStr += ")"; 7227 S.Diag(OpLoc, diag::note_ovl_builtin_binary_candidate) << TypeStr; 7228 } 7229} 7230 7231void NoteAmbiguousUserConversions(Sema &S, SourceLocation OpLoc, 7232 OverloadCandidate *Cand) { 7233 unsigned NoOperands = Cand->Conversions.size(); 7234 for (unsigned ArgIdx = 0; ArgIdx < NoOperands; ++ArgIdx) { 7235 const ImplicitConversionSequence &ICS = Cand->Conversions[ArgIdx]; 7236 if (ICS.isBad()) break; // all meaningless after first invalid 7237 if (!ICS.isAmbiguous()) continue; 7238 7239 ICS.DiagnoseAmbiguousConversion(S, OpLoc, 7240 S.PDiag(diag::note_ambiguous_type_conversion)); 7241 } 7242} 7243 7244SourceLocation GetLocationForCandidate(const OverloadCandidate *Cand) { 7245 if (Cand->Function) 7246 return Cand->Function->getLocation(); 7247 if (Cand->IsSurrogate) 7248 return Cand->Surrogate->getLocation(); 7249 return SourceLocation(); 7250} 7251 7252struct CompareOverloadCandidatesForDisplay { 7253 Sema &S; 7254 CompareOverloadCandidatesForDisplay(Sema &S) : S(S) {} 7255 7256 bool operator()(const OverloadCandidate *L, 7257 const OverloadCandidate *R) { 7258 // Fast-path this check. 7259 if (L == R) return false; 7260 7261 // Order first by viability. 7262 if (L->Viable) { 7263 if (!R->Viable) return true; 7264 7265 // TODO: introduce a tri-valued comparison for overload 7266 // candidates. Would be more worthwhile if we had a sort 7267 // that could exploit it. 7268 if (isBetterOverloadCandidate(S, *L, *R, SourceLocation())) return true; 7269 if (isBetterOverloadCandidate(S, *R, *L, SourceLocation())) return false; 7270 } else if (R->Viable) 7271 return false; 7272 7273 assert(L->Viable == R->Viable); 7274 7275 // Criteria by which we can sort non-viable candidates: 7276 if (!L->Viable) { 7277 // 1. Arity mismatches come after other candidates. 7278 if (L->FailureKind == ovl_fail_too_many_arguments || 7279 L->FailureKind == ovl_fail_too_few_arguments) 7280 return false; 7281 if (R->FailureKind == ovl_fail_too_many_arguments || 7282 R->FailureKind == ovl_fail_too_few_arguments) 7283 return true; 7284 7285 // 2. Bad conversions come first and are ordered by the number 7286 // of bad conversions and quality of good conversions. 7287 if (L->FailureKind == ovl_fail_bad_conversion) { 7288 if (R->FailureKind != ovl_fail_bad_conversion) 7289 return true; 7290 7291 // The conversion that can be fixed with a smaller number of changes, 7292 // comes first. 7293 unsigned numLFixes = L->Fix.NumConversionsFixed; 7294 unsigned numRFixes = R->Fix.NumConversionsFixed; 7295 numLFixes = (numLFixes == 0) ? UINT_MAX : numLFixes; 7296 numRFixes = (numRFixes == 0) ? UINT_MAX : numRFixes; 7297 if (numLFixes != numRFixes) { 7298 if (numLFixes < numRFixes) 7299 return true; 7300 else 7301 return false; 7302 } 7303 7304 // If there's any ordering between the defined conversions... 7305 // FIXME: this might not be transitive. 7306 assert(L->Conversions.size() == R->Conversions.size()); 7307 7308 int leftBetter = 0; 7309 unsigned I = (L->IgnoreObjectArgument || R->IgnoreObjectArgument); 7310 for (unsigned E = L->Conversions.size(); I != E; ++I) { 7311 switch (CompareImplicitConversionSequences(S, 7312 L->Conversions[I], 7313 R->Conversions[I])) { 7314 case ImplicitConversionSequence::Better: 7315 leftBetter++; 7316 break; 7317 7318 case ImplicitConversionSequence::Worse: 7319 leftBetter--; 7320 break; 7321 7322 case ImplicitConversionSequence::Indistinguishable: 7323 break; 7324 } 7325 } 7326 if (leftBetter > 0) return true; 7327 if (leftBetter < 0) return false; 7328 7329 } else if (R->FailureKind == ovl_fail_bad_conversion) 7330 return false; 7331 7332 // TODO: others? 7333 } 7334 7335 // Sort everything else by location. 7336 SourceLocation LLoc = GetLocationForCandidate(L); 7337 SourceLocation RLoc = GetLocationForCandidate(R); 7338 7339 // Put candidates without locations (e.g. builtins) at the end. 7340 if (LLoc.isInvalid()) return false; 7341 if (RLoc.isInvalid()) return true; 7342 7343 return S.SourceMgr.isBeforeInTranslationUnit(LLoc, RLoc); 7344 } 7345}; 7346 7347/// CompleteNonViableCandidate - Normally, overload resolution only 7348/// computes up to the first. Produces the FixIt set if possible. 7349void CompleteNonViableCandidate(Sema &S, OverloadCandidate *Cand, 7350 Expr **Args, unsigned NumArgs) { 7351 assert(!Cand->Viable); 7352 7353 // Don't do anything on failures other than bad conversion. 7354 if (Cand->FailureKind != ovl_fail_bad_conversion) return; 7355 7356 // We only want the FixIts if all the arguments can be corrected. 7357 bool Unfixable = false; 7358 // Use a implicit copy initialization to check conversion fixes. 7359 Cand->Fix.setConversionChecker(TryCopyInitialization); 7360 7361 // Skip forward to the first bad conversion. 7362 unsigned ConvIdx = (Cand->IgnoreObjectArgument ? 1 : 0); 7363 unsigned ConvCount = Cand->Conversions.size(); 7364 while (true) { 7365 assert(ConvIdx != ConvCount && "no bad conversion in candidate"); 7366 ConvIdx++; 7367 if (Cand->Conversions[ConvIdx - 1].isBad()) { 7368 Unfixable = !Cand->TryToFixBadConversion(ConvIdx - 1, S); 7369 break; 7370 } 7371 } 7372 7373 if (ConvIdx == ConvCount) 7374 return; 7375 7376 assert(!Cand->Conversions[ConvIdx].isInitialized() && 7377 "remaining conversion is initialized?"); 7378 7379 // FIXME: this should probably be preserved from the overload 7380 // operation somehow. 7381 bool SuppressUserConversions = false; 7382 7383 const FunctionProtoType* Proto; 7384 unsigned ArgIdx = ConvIdx; 7385 7386 if (Cand->IsSurrogate) { 7387 QualType ConvType 7388 = Cand->Surrogate->getConversionType().getNonReferenceType(); 7389 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 7390 ConvType = ConvPtrType->getPointeeType(); 7391 Proto = ConvType->getAs<FunctionProtoType>(); 7392 ArgIdx--; 7393 } else if (Cand->Function) { 7394 Proto = Cand->Function->getType()->getAs<FunctionProtoType>(); 7395 if (isa<CXXMethodDecl>(Cand->Function) && 7396 !isa<CXXConstructorDecl>(Cand->Function)) 7397 ArgIdx--; 7398 } else { 7399 // Builtin binary operator with a bad first conversion. 7400 assert(ConvCount <= 3); 7401 for (; ConvIdx != ConvCount; ++ConvIdx) 7402 Cand->Conversions[ConvIdx] 7403 = TryCopyInitialization(S, Args[ConvIdx], 7404 Cand->BuiltinTypes.ParamTypes[ConvIdx], 7405 SuppressUserConversions, 7406 /*InOverloadResolution*/ true, 7407 /*AllowObjCWritebackConversion=*/ 7408 S.getLangOptions().ObjCAutoRefCount); 7409 return; 7410 } 7411 7412 // Fill in the rest of the conversions. 7413 unsigned NumArgsInProto = Proto->getNumArgs(); 7414 for (; ConvIdx != ConvCount; ++ConvIdx, ++ArgIdx) { 7415 if (ArgIdx < NumArgsInProto) { 7416 Cand->Conversions[ConvIdx] 7417 = TryCopyInitialization(S, Args[ArgIdx], Proto->getArgType(ArgIdx), 7418 SuppressUserConversions, 7419 /*InOverloadResolution=*/true, 7420 /*AllowObjCWritebackConversion=*/ 7421 S.getLangOptions().ObjCAutoRefCount); 7422 // Store the FixIt in the candidate if it exists. 7423 if (!Unfixable && Cand->Conversions[ConvIdx].isBad()) 7424 Unfixable = !Cand->TryToFixBadConversion(ConvIdx, S); 7425 } 7426 else 7427 Cand->Conversions[ConvIdx].setEllipsis(); 7428 } 7429} 7430 7431} // end anonymous namespace 7432 7433/// PrintOverloadCandidates - When overload resolution fails, prints 7434/// diagnostic messages containing the candidates in the candidate 7435/// set. 7436void OverloadCandidateSet::NoteCandidates(Sema &S, 7437 OverloadCandidateDisplayKind OCD, 7438 Expr **Args, unsigned NumArgs, 7439 const char *Opc, 7440 SourceLocation OpLoc) { 7441 // Sort the candidates by viability and position. Sorting directly would 7442 // be prohibitive, so we make a set of pointers and sort those. 7443 SmallVector<OverloadCandidate*, 32> Cands; 7444 if (OCD == OCD_AllCandidates) Cands.reserve(size()); 7445 for (iterator Cand = begin(), LastCand = end(); Cand != LastCand; ++Cand) { 7446 if (Cand->Viable) 7447 Cands.push_back(Cand); 7448 else if (OCD == OCD_AllCandidates) { 7449 CompleteNonViableCandidate(S, Cand, Args, NumArgs); 7450 if (Cand->Function || Cand->IsSurrogate) 7451 Cands.push_back(Cand); 7452 // Otherwise, this a non-viable builtin candidate. We do not, in general, 7453 // want to list every possible builtin candidate. 7454 } 7455 } 7456 7457 std::sort(Cands.begin(), Cands.end(), 7458 CompareOverloadCandidatesForDisplay(S)); 7459 7460 bool ReportedAmbiguousConversions = false; 7461 7462 SmallVectorImpl<OverloadCandidate*>::iterator I, E; 7463 const Diagnostic::OverloadsShown ShowOverloads = S.Diags.getShowOverloads(); 7464 unsigned CandsShown = 0; 7465 for (I = Cands.begin(), E = Cands.end(); I != E; ++I) { 7466 OverloadCandidate *Cand = *I; 7467 7468 // Set an arbitrary limit on the number of candidate functions we'll spam 7469 // the user with. FIXME: This limit should depend on details of the 7470 // candidate list. 7471 if (CandsShown >= 4 && ShowOverloads == Diagnostic::Ovl_Best) { 7472 break; 7473 } 7474 ++CandsShown; 7475 7476 if (Cand->Function) 7477 NoteFunctionCandidate(S, Cand, Args, NumArgs); 7478 else if (Cand->IsSurrogate) 7479 NoteSurrogateCandidate(S, Cand); 7480 else { 7481 assert(Cand->Viable && 7482 "Non-viable built-in candidates are not added to Cands."); 7483 // Generally we only see ambiguities including viable builtin 7484 // operators if overload resolution got screwed up by an 7485 // ambiguous user-defined conversion. 7486 // 7487 // FIXME: It's quite possible for different conversions to see 7488 // different ambiguities, though. 7489 if (!ReportedAmbiguousConversions) { 7490 NoteAmbiguousUserConversions(S, OpLoc, Cand); 7491 ReportedAmbiguousConversions = true; 7492 } 7493 7494 // If this is a viable builtin, print it. 7495 NoteBuiltinOperatorCandidate(S, Opc, OpLoc, Cand); 7496 } 7497 } 7498 7499 if (I != E) 7500 S.Diag(OpLoc, diag::note_ovl_too_many_candidates) << int(E - I); 7501} 7502 7503// [PossiblyAFunctionType] --> [Return] 7504// NonFunctionType --> NonFunctionType 7505// R (A) --> R(A) 7506// R (*)(A) --> R (A) 7507// R (&)(A) --> R (A) 7508// R (S::*)(A) --> R (A) 7509QualType Sema::ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType) { 7510 QualType Ret = PossiblyAFunctionType; 7511 if (const PointerType *ToTypePtr = 7512 PossiblyAFunctionType->getAs<PointerType>()) 7513 Ret = ToTypePtr->getPointeeType(); 7514 else if (const ReferenceType *ToTypeRef = 7515 PossiblyAFunctionType->getAs<ReferenceType>()) 7516 Ret = ToTypeRef->getPointeeType(); 7517 else if (const MemberPointerType *MemTypePtr = 7518 PossiblyAFunctionType->getAs<MemberPointerType>()) 7519 Ret = MemTypePtr->getPointeeType(); 7520 Ret = 7521 Context.getCanonicalType(Ret).getUnqualifiedType(); 7522 return Ret; 7523} 7524 7525// A helper class to help with address of function resolution 7526// - allows us to avoid passing around all those ugly parameters 7527class AddressOfFunctionResolver 7528{ 7529 Sema& S; 7530 Expr* SourceExpr; 7531 const QualType& TargetType; 7532 QualType TargetFunctionType; // Extracted function type from target type 7533 7534 bool Complain; 7535 //DeclAccessPair& ResultFunctionAccessPair; 7536 ASTContext& Context; 7537 7538 bool TargetTypeIsNonStaticMemberFunction; 7539 bool FoundNonTemplateFunction; 7540 7541 OverloadExpr::FindResult OvlExprInfo; 7542 OverloadExpr *OvlExpr; 7543 TemplateArgumentListInfo OvlExplicitTemplateArgs; 7544 SmallVector<std::pair<DeclAccessPair, FunctionDecl*>, 4> Matches; 7545 7546public: 7547 AddressOfFunctionResolver(Sema &S, Expr* SourceExpr, 7548 const QualType& TargetType, bool Complain) 7549 : S(S), SourceExpr(SourceExpr), TargetType(TargetType), 7550 Complain(Complain), Context(S.getASTContext()), 7551 TargetTypeIsNonStaticMemberFunction( 7552 !!TargetType->getAs<MemberPointerType>()), 7553 FoundNonTemplateFunction(false), 7554 OvlExprInfo(OverloadExpr::find(SourceExpr)), 7555 OvlExpr(OvlExprInfo.Expression) 7556 { 7557 ExtractUnqualifiedFunctionTypeFromTargetType(); 7558 7559 if (!TargetFunctionType->isFunctionType()) { 7560 if (OvlExpr->hasExplicitTemplateArgs()) { 7561 DeclAccessPair dap; 7562 if (FunctionDecl* Fn = S.ResolveSingleFunctionTemplateSpecialization( 7563 OvlExpr, false, &dap) ) { 7564 7565 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 7566 if (!Method->isStatic()) { 7567 // If the target type is a non-function type and the function 7568 // found is a non-static member function, pretend as if that was 7569 // the target, it's the only possible type to end up with. 7570 TargetTypeIsNonStaticMemberFunction = true; 7571 7572 // And skip adding the function if its not in the proper form. 7573 // We'll diagnose this due to an empty set of functions. 7574 if (!OvlExprInfo.HasFormOfMemberPointer) 7575 return; 7576 } 7577 } 7578 7579 Matches.push_back(std::make_pair(dap,Fn)); 7580 } 7581 } 7582 return; 7583 } 7584 7585 if (OvlExpr->hasExplicitTemplateArgs()) 7586 OvlExpr->getExplicitTemplateArgs().copyInto(OvlExplicitTemplateArgs); 7587 7588 if (FindAllFunctionsThatMatchTargetTypeExactly()) { 7589 // C++ [over.over]p4: 7590 // If more than one function is selected, [...] 7591 if (Matches.size() > 1) { 7592 if (FoundNonTemplateFunction) 7593 EliminateAllTemplateMatches(); 7594 else 7595 EliminateAllExceptMostSpecializedTemplate(); 7596 } 7597 } 7598 } 7599 7600private: 7601 bool isTargetTypeAFunction() const { 7602 return TargetFunctionType->isFunctionType(); 7603 } 7604 7605 // [ToType] [Return] 7606 7607 // R (*)(A) --> R (A), IsNonStaticMemberFunction = false 7608 // R (&)(A) --> R (A), IsNonStaticMemberFunction = false 7609 // R (S::*)(A) --> R (A), IsNonStaticMemberFunction = true 7610 void inline ExtractUnqualifiedFunctionTypeFromTargetType() { 7611 TargetFunctionType = S.ExtractUnqualifiedFunctionType(TargetType); 7612 } 7613 7614 // return true if any matching specializations were found 7615 bool AddMatchingTemplateFunction(FunctionTemplateDecl* FunctionTemplate, 7616 const DeclAccessPair& CurAccessFunPair) { 7617 if (CXXMethodDecl *Method 7618 = dyn_cast<CXXMethodDecl>(FunctionTemplate->getTemplatedDecl())) { 7619 // Skip non-static function templates when converting to pointer, and 7620 // static when converting to member pointer. 7621 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 7622 return false; 7623 } 7624 else if (TargetTypeIsNonStaticMemberFunction) 7625 return false; 7626 7627 // C++ [over.over]p2: 7628 // If the name is a function template, template argument deduction is 7629 // done (14.8.2.2), and if the argument deduction succeeds, the 7630 // resulting template argument list is used to generate a single 7631 // function template specialization, which is added to the set of 7632 // overloaded functions considered. 7633 FunctionDecl *Specialization = 0; 7634 TemplateDeductionInfo Info(Context, OvlExpr->getNameLoc()); 7635 if (Sema::TemplateDeductionResult Result 7636 = S.DeduceTemplateArguments(FunctionTemplate, 7637 &OvlExplicitTemplateArgs, 7638 TargetFunctionType, Specialization, 7639 Info)) { 7640 // FIXME: make a note of the failed deduction for diagnostics. 7641 (void)Result; 7642 return false; 7643 } 7644 7645 // Template argument deduction ensures that we have an exact match. 7646 // This function template specicalization works. 7647 Specialization = cast<FunctionDecl>(Specialization->getCanonicalDecl()); 7648 assert(TargetFunctionType 7649 == Context.getCanonicalType(Specialization->getType())); 7650 Matches.push_back(std::make_pair(CurAccessFunPair, Specialization)); 7651 return true; 7652 } 7653 7654 bool AddMatchingNonTemplateFunction(NamedDecl* Fn, 7655 const DeclAccessPair& CurAccessFunPair) { 7656 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 7657 // Skip non-static functions when converting to pointer, and static 7658 // when converting to member pointer. 7659 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 7660 return false; 7661 } 7662 else if (TargetTypeIsNonStaticMemberFunction) 7663 return false; 7664 7665 if (FunctionDecl *FunDecl = dyn_cast<FunctionDecl>(Fn)) { 7666 QualType ResultTy; 7667 if (Context.hasSameUnqualifiedType(TargetFunctionType, 7668 FunDecl->getType()) || 7669 S.IsNoReturnConversion(FunDecl->getType(), TargetFunctionType, 7670 ResultTy)) { 7671 Matches.push_back(std::make_pair(CurAccessFunPair, 7672 cast<FunctionDecl>(FunDecl->getCanonicalDecl()))); 7673 FoundNonTemplateFunction = true; 7674 return true; 7675 } 7676 } 7677 7678 return false; 7679 } 7680 7681 bool FindAllFunctionsThatMatchTargetTypeExactly() { 7682 bool Ret = false; 7683 7684 // If the overload expression doesn't have the form of a pointer to 7685 // member, don't try to convert it to a pointer-to-member type. 7686 if (IsInvalidFormOfPointerToMemberFunction()) 7687 return false; 7688 7689 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 7690 E = OvlExpr->decls_end(); 7691 I != E; ++I) { 7692 // Look through any using declarations to find the underlying function. 7693 NamedDecl *Fn = (*I)->getUnderlyingDecl(); 7694 7695 // C++ [over.over]p3: 7696 // Non-member functions and static member functions match 7697 // targets of type "pointer-to-function" or "reference-to-function." 7698 // Nonstatic member functions match targets of 7699 // type "pointer-to-member-function." 7700 // Note that according to DR 247, the containing class does not matter. 7701 if (FunctionTemplateDecl *FunctionTemplate 7702 = dyn_cast<FunctionTemplateDecl>(Fn)) { 7703 if (AddMatchingTemplateFunction(FunctionTemplate, I.getPair())) 7704 Ret = true; 7705 } 7706 // If we have explicit template arguments supplied, skip non-templates. 7707 else if (!OvlExpr->hasExplicitTemplateArgs() && 7708 AddMatchingNonTemplateFunction(Fn, I.getPair())) 7709 Ret = true; 7710 } 7711 assert(Ret || Matches.empty()); 7712 return Ret; 7713 } 7714 7715 void EliminateAllExceptMostSpecializedTemplate() { 7716 // [...] and any given function template specialization F1 is 7717 // eliminated if the set contains a second function template 7718 // specialization whose function template is more specialized 7719 // than the function template of F1 according to the partial 7720 // ordering rules of 14.5.5.2. 7721 7722 // The algorithm specified above is quadratic. We instead use a 7723 // two-pass algorithm (similar to the one used to identify the 7724 // best viable function in an overload set) that identifies the 7725 // best function template (if it exists). 7726 7727 UnresolvedSet<4> MatchesCopy; // TODO: avoid! 7728 for (unsigned I = 0, E = Matches.size(); I != E; ++I) 7729 MatchesCopy.addDecl(Matches[I].second, Matches[I].first.getAccess()); 7730 7731 UnresolvedSetIterator Result = 7732 S.getMostSpecialized(MatchesCopy.begin(), MatchesCopy.end(), 7733 TPOC_Other, 0, SourceExpr->getLocStart(), 7734 S.PDiag(), 7735 S.PDiag(diag::err_addr_ovl_ambiguous) 7736 << Matches[0].second->getDeclName(), 7737 S.PDiag(diag::note_ovl_candidate) 7738 << (unsigned) oc_function_template, 7739 Complain); 7740 7741 if (Result != MatchesCopy.end()) { 7742 // Make it the first and only element 7743 Matches[0].first = Matches[Result - MatchesCopy.begin()].first; 7744 Matches[0].second = cast<FunctionDecl>(*Result); 7745 Matches.resize(1); 7746 } 7747 } 7748 7749 void EliminateAllTemplateMatches() { 7750 // [...] any function template specializations in the set are 7751 // eliminated if the set also contains a non-template function, [...] 7752 for (unsigned I = 0, N = Matches.size(); I != N; ) { 7753 if (Matches[I].second->getPrimaryTemplate() == 0) 7754 ++I; 7755 else { 7756 Matches[I] = Matches[--N]; 7757 Matches.set_size(N); 7758 } 7759 } 7760 } 7761 7762public: 7763 void ComplainNoMatchesFound() const { 7764 assert(Matches.empty()); 7765 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_no_viable) 7766 << OvlExpr->getName() << TargetFunctionType 7767 << OvlExpr->getSourceRange(); 7768 S.NoteAllOverloadCandidates(OvlExpr); 7769 } 7770 7771 bool IsInvalidFormOfPointerToMemberFunction() const { 7772 return TargetTypeIsNonStaticMemberFunction && 7773 !OvlExprInfo.HasFormOfMemberPointer; 7774 } 7775 7776 void ComplainIsInvalidFormOfPointerToMemberFunction() const { 7777 // TODO: Should we condition this on whether any functions might 7778 // have matched, or is it more appropriate to do that in callers? 7779 // TODO: a fixit wouldn't hurt. 7780 S.Diag(OvlExpr->getNameLoc(), diag::err_addr_ovl_no_qualifier) 7781 << TargetType << OvlExpr->getSourceRange(); 7782 } 7783 7784 void ComplainOfInvalidConversion() const { 7785 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_not_func_ptrref) 7786 << OvlExpr->getName() << TargetType; 7787 } 7788 7789 void ComplainMultipleMatchesFound() const { 7790 assert(Matches.size() > 1); 7791 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_ambiguous) 7792 << OvlExpr->getName() 7793 << OvlExpr->getSourceRange(); 7794 S.NoteAllOverloadCandidates(OvlExpr); 7795 } 7796 7797 int getNumMatches() const { return Matches.size(); } 7798 7799 FunctionDecl* getMatchingFunctionDecl() const { 7800 if (Matches.size() != 1) return 0; 7801 return Matches[0].second; 7802 } 7803 7804 const DeclAccessPair* getMatchingFunctionAccessPair() const { 7805 if (Matches.size() != 1) return 0; 7806 return &Matches[0].first; 7807 } 7808}; 7809 7810/// ResolveAddressOfOverloadedFunction - Try to resolve the address of 7811/// an overloaded function (C++ [over.over]), where @p From is an 7812/// expression with overloaded function type and @p ToType is the type 7813/// we're trying to resolve to. For example: 7814/// 7815/// @code 7816/// int f(double); 7817/// int f(int); 7818/// 7819/// int (*pfd)(double) = f; // selects f(double) 7820/// @endcode 7821/// 7822/// This routine returns the resulting FunctionDecl if it could be 7823/// resolved, and NULL otherwise. When @p Complain is true, this 7824/// routine will emit diagnostics if there is an error. 7825FunctionDecl * 7826Sema::ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr, QualType TargetType, 7827 bool Complain, 7828 DeclAccessPair &FoundResult) { 7829 7830 assert(AddressOfExpr->getType() == Context.OverloadTy); 7831 7832 AddressOfFunctionResolver Resolver(*this, AddressOfExpr, TargetType, Complain); 7833 int NumMatches = Resolver.getNumMatches(); 7834 FunctionDecl* Fn = 0; 7835 if ( NumMatches == 0 && Complain) { 7836 if (Resolver.IsInvalidFormOfPointerToMemberFunction()) 7837 Resolver.ComplainIsInvalidFormOfPointerToMemberFunction(); 7838 else 7839 Resolver.ComplainNoMatchesFound(); 7840 } 7841 else if (NumMatches > 1 && Complain) 7842 Resolver.ComplainMultipleMatchesFound(); 7843 else if (NumMatches == 1) { 7844 Fn = Resolver.getMatchingFunctionDecl(); 7845 assert(Fn); 7846 FoundResult = *Resolver.getMatchingFunctionAccessPair(); 7847 MarkDeclarationReferenced(AddressOfExpr->getLocStart(), Fn); 7848 if (Complain) 7849 CheckAddressOfMemberAccess(AddressOfExpr, FoundResult); 7850 } 7851 7852 return Fn; 7853} 7854 7855/// \brief Given an expression that refers to an overloaded function, try to 7856/// resolve that overloaded function expression down to a single function. 7857/// 7858/// This routine can only resolve template-ids that refer to a single function 7859/// template, where that template-id refers to a single template whose template 7860/// arguments are either provided by the template-id or have defaults, 7861/// as described in C++0x [temp.arg.explicit]p3. 7862FunctionDecl * 7863Sema::ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl, 7864 bool Complain, 7865 DeclAccessPair *FoundResult) { 7866 // C++ [over.over]p1: 7867 // [...] [Note: any redundant set of parentheses surrounding the 7868 // overloaded function name is ignored (5.1). ] 7869 // C++ [over.over]p1: 7870 // [...] The overloaded function name can be preceded by the & 7871 // operator. 7872 7873 // If we didn't actually find any template-ids, we're done. 7874 if (!ovl->hasExplicitTemplateArgs()) 7875 return 0; 7876 7877 TemplateArgumentListInfo ExplicitTemplateArgs; 7878 ovl->getExplicitTemplateArgs().copyInto(ExplicitTemplateArgs); 7879 7880 // Look through all of the overloaded functions, searching for one 7881 // whose type matches exactly. 7882 FunctionDecl *Matched = 0; 7883 for (UnresolvedSetIterator I = ovl->decls_begin(), 7884 E = ovl->decls_end(); I != E; ++I) { 7885 // C++0x [temp.arg.explicit]p3: 7886 // [...] In contexts where deduction is done and fails, or in contexts 7887 // where deduction is not done, if a template argument list is 7888 // specified and it, along with any default template arguments, 7889 // identifies a single function template specialization, then the 7890 // template-id is an lvalue for the function template specialization. 7891 FunctionTemplateDecl *FunctionTemplate 7892 = cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()); 7893 7894 // C++ [over.over]p2: 7895 // If the name is a function template, template argument deduction is 7896 // done (14.8.2.2), and if the argument deduction succeeds, the 7897 // resulting template argument list is used to generate a single 7898 // function template specialization, which is added to the set of 7899 // overloaded functions considered. 7900 FunctionDecl *Specialization = 0; 7901 TemplateDeductionInfo Info(Context, ovl->getNameLoc()); 7902 if (TemplateDeductionResult Result 7903 = DeduceTemplateArguments(FunctionTemplate, &ExplicitTemplateArgs, 7904 Specialization, Info)) { 7905 // FIXME: make a note of the failed deduction for diagnostics. 7906 (void)Result; 7907 continue; 7908 } 7909 7910 assert(Specialization && "no specialization and no error?"); 7911 7912 // Multiple matches; we can't resolve to a single declaration. 7913 if (Matched) { 7914 if (Complain) { 7915 Diag(ovl->getExprLoc(), diag::err_addr_ovl_ambiguous) 7916 << ovl->getName(); 7917 NoteAllOverloadCandidates(ovl); 7918 } 7919 return 0; 7920 } 7921 7922 Matched = Specialization; 7923 if (FoundResult) *FoundResult = I.getPair(); 7924 } 7925 7926 return Matched; 7927} 7928 7929 7930 7931 7932// Resolve and fix an overloaded expression that 7933// can be resolved because it identifies a single function 7934// template specialization 7935// Last three arguments should only be supplied if Complain = true 7936ExprResult Sema::ResolveAndFixSingleFunctionTemplateSpecialization( 7937 Expr *SrcExpr, bool doFunctionPointerConverion, bool complain, 7938 const SourceRange& OpRangeForComplaining, 7939 QualType DestTypeForComplaining, 7940 unsigned DiagIDForComplaining) { 7941 assert(SrcExpr->getType() == Context.OverloadTy); 7942 7943 OverloadExpr::FindResult ovl = OverloadExpr::find(SrcExpr); 7944 7945 DeclAccessPair found; 7946 ExprResult SingleFunctionExpression; 7947 if (FunctionDecl *fn = ResolveSingleFunctionTemplateSpecialization( 7948 ovl.Expression, /*complain*/ false, &found)) { 7949 if (DiagnoseUseOfDecl(fn, SrcExpr->getSourceRange().getBegin())) 7950 return ExprError(); 7951 7952 // It is only correct to resolve to an instance method if we're 7953 // resolving a form that's permitted to be a pointer to member. 7954 // Otherwise we'll end up making a bound member expression, which 7955 // is illegal in all the contexts we resolve like this. 7956 if (!ovl.HasFormOfMemberPointer && 7957 isa<CXXMethodDecl>(fn) && 7958 cast<CXXMethodDecl>(fn)->isInstance()) { 7959 if (complain) { 7960 Diag(ovl.Expression->getExprLoc(), 7961 diag::err_invalid_use_of_bound_member_func) 7962 << ovl.Expression->getSourceRange(); 7963 // TODO: I believe we only end up here if there's a mix of 7964 // static and non-static candidates (otherwise the expression 7965 // would have 'bound member' type, not 'overload' type). 7966 // Ideally we would note which candidate was chosen and why 7967 // the static candidates were rejected. 7968 } 7969 7970 return ExprError(); 7971 } 7972 7973 // Fix the expresion to refer to 'fn'. 7974 SingleFunctionExpression = 7975 Owned(FixOverloadedFunctionReference(SrcExpr, found, fn)); 7976 7977 // If desired, do function-to-pointer decay. 7978 if (doFunctionPointerConverion) 7979 SingleFunctionExpression = 7980 DefaultFunctionArrayLvalueConversion(SingleFunctionExpression.take()); 7981 } 7982 7983 if (!SingleFunctionExpression.isUsable()) { 7984 if (complain) { 7985 Diag(OpRangeForComplaining.getBegin(), DiagIDForComplaining) 7986 << ovl.Expression->getName() 7987 << DestTypeForComplaining 7988 << OpRangeForComplaining 7989 << ovl.Expression->getQualifierLoc().getSourceRange(); 7990 NoteAllOverloadCandidates(SrcExpr); 7991 } 7992 return ExprError(); 7993 } 7994 7995 return SingleFunctionExpression; 7996} 7997 7998/// \brief Add a single candidate to the overload set. 7999static void AddOverloadedCallCandidate(Sema &S, 8000 DeclAccessPair FoundDecl, 8001 TemplateArgumentListInfo *ExplicitTemplateArgs, 8002 Expr **Args, unsigned NumArgs, 8003 OverloadCandidateSet &CandidateSet, 8004 bool PartialOverloading, 8005 bool KnownValid) { 8006 NamedDecl *Callee = FoundDecl.getDecl(); 8007 if (isa<UsingShadowDecl>(Callee)) 8008 Callee = cast<UsingShadowDecl>(Callee)->getTargetDecl(); 8009 8010 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(Callee)) { 8011 if (ExplicitTemplateArgs) { 8012 assert(!KnownValid && "Explicit template arguments?"); 8013 return; 8014 } 8015 S.AddOverloadCandidate(Func, FoundDecl, Args, NumArgs, CandidateSet, 8016 false, PartialOverloading); 8017 return; 8018 } 8019 8020 if (FunctionTemplateDecl *FuncTemplate 8021 = dyn_cast<FunctionTemplateDecl>(Callee)) { 8022 S.AddTemplateOverloadCandidate(FuncTemplate, FoundDecl, 8023 ExplicitTemplateArgs, 8024 Args, NumArgs, CandidateSet); 8025 return; 8026 } 8027 8028 assert(!KnownValid && "unhandled case in overloaded call candidate"); 8029} 8030 8031/// \brief Add the overload candidates named by callee and/or found by argument 8032/// dependent lookup to the given overload set. 8033void Sema::AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE, 8034 Expr **Args, unsigned NumArgs, 8035 OverloadCandidateSet &CandidateSet, 8036 bool PartialOverloading) { 8037 8038#ifndef NDEBUG 8039 // Verify that ArgumentDependentLookup is consistent with the rules 8040 // in C++0x [basic.lookup.argdep]p3: 8041 // 8042 // Let X be the lookup set produced by unqualified lookup (3.4.1) 8043 // and let Y be the lookup set produced by argument dependent 8044 // lookup (defined as follows). If X contains 8045 // 8046 // -- a declaration of a class member, or 8047 // 8048 // -- a block-scope function declaration that is not a 8049 // using-declaration, or 8050 // 8051 // -- a declaration that is neither a function or a function 8052 // template 8053 // 8054 // then Y is empty. 8055 8056 if (ULE->requiresADL()) { 8057 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 8058 E = ULE->decls_end(); I != E; ++I) { 8059 assert(!(*I)->getDeclContext()->isRecord()); 8060 assert(isa<UsingShadowDecl>(*I) || 8061 !(*I)->getDeclContext()->isFunctionOrMethod()); 8062 assert((*I)->getUnderlyingDecl()->isFunctionOrFunctionTemplate()); 8063 } 8064 } 8065#endif 8066 8067 // It would be nice to avoid this copy. 8068 TemplateArgumentListInfo TABuffer; 8069 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 8070 if (ULE->hasExplicitTemplateArgs()) { 8071 ULE->copyTemplateArgumentsInto(TABuffer); 8072 ExplicitTemplateArgs = &TABuffer; 8073 } 8074 8075 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 8076 E = ULE->decls_end(); I != E; ++I) 8077 AddOverloadedCallCandidate(*this, I.getPair(), ExplicitTemplateArgs, 8078 Args, NumArgs, CandidateSet, 8079 PartialOverloading, /*KnownValid*/ true); 8080 8081 if (ULE->requiresADL()) 8082 AddArgumentDependentLookupCandidates(ULE->getName(), /*Operator*/ false, 8083 Args, NumArgs, 8084 ExplicitTemplateArgs, 8085 CandidateSet, 8086 PartialOverloading, 8087 ULE->isStdAssociatedNamespace()); 8088} 8089 8090/// Attempt to recover from an ill-formed use of a non-dependent name in a 8091/// template, where the non-dependent name was declared after the template 8092/// was defined. This is common in code written for a compilers which do not 8093/// correctly implement two-stage name lookup. 8094/// 8095/// Returns true if a viable candidate was found and a diagnostic was issued. 8096static bool 8097DiagnoseTwoPhaseLookup(Sema &SemaRef, SourceLocation FnLoc, 8098 const CXXScopeSpec &SS, LookupResult &R, 8099 TemplateArgumentListInfo *ExplicitTemplateArgs, 8100 Expr **Args, unsigned NumArgs) { 8101 if (SemaRef.ActiveTemplateInstantiations.empty() || !SS.isEmpty()) 8102 return false; 8103 8104 for (DeclContext *DC = SemaRef.CurContext; DC; DC = DC->getParent()) { 8105 SemaRef.LookupQualifiedName(R, DC); 8106 8107 if (!R.empty()) { 8108 R.suppressDiagnostics(); 8109 8110 if (isa<CXXRecordDecl>(DC)) { 8111 // Don't diagnose names we find in classes; we get much better 8112 // diagnostics for these from DiagnoseEmptyLookup. 8113 R.clear(); 8114 return false; 8115 } 8116 8117 OverloadCandidateSet Candidates(FnLoc); 8118 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 8119 AddOverloadedCallCandidate(SemaRef, I.getPair(), 8120 ExplicitTemplateArgs, Args, NumArgs, 8121 Candidates, false, /*KnownValid*/ false); 8122 8123 OverloadCandidateSet::iterator Best; 8124 if (Candidates.BestViableFunction(SemaRef, FnLoc, Best) != OR_Success) { 8125 // No viable functions. Don't bother the user with notes for functions 8126 // which don't work and shouldn't be found anyway. 8127 R.clear(); 8128 return false; 8129 } 8130 8131 // Find the namespaces where ADL would have looked, and suggest 8132 // declaring the function there instead. 8133 Sema::AssociatedNamespaceSet AssociatedNamespaces; 8134 Sema::AssociatedClassSet AssociatedClasses; 8135 SemaRef.FindAssociatedClassesAndNamespaces(Args, NumArgs, 8136 AssociatedNamespaces, 8137 AssociatedClasses); 8138 // Never suggest declaring a function within namespace 'std'. 8139 Sema::AssociatedNamespaceSet SuggestedNamespaces; 8140 if (DeclContext *Std = SemaRef.getStdNamespace()) { 8141 for (Sema::AssociatedNamespaceSet::iterator 8142 it = AssociatedNamespaces.begin(), 8143 end = AssociatedNamespaces.end(); it != end; ++it) { 8144 if (!Std->Encloses(*it)) 8145 SuggestedNamespaces.insert(*it); 8146 } 8147 } else { 8148 // Lacking the 'std::' namespace, use all of the associated namespaces. 8149 SuggestedNamespaces = AssociatedNamespaces; 8150 } 8151 8152 SemaRef.Diag(R.getNameLoc(), diag::err_not_found_by_two_phase_lookup) 8153 << R.getLookupName(); 8154 if (SuggestedNamespaces.empty()) { 8155 SemaRef.Diag(Best->Function->getLocation(), 8156 diag::note_not_found_by_two_phase_lookup) 8157 << R.getLookupName() << 0; 8158 } else if (SuggestedNamespaces.size() == 1) { 8159 SemaRef.Diag(Best->Function->getLocation(), 8160 diag::note_not_found_by_two_phase_lookup) 8161 << R.getLookupName() << 1 << *SuggestedNamespaces.begin(); 8162 } else { 8163 // FIXME: It would be useful to list the associated namespaces here, 8164 // but the diagnostics infrastructure doesn't provide a way to produce 8165 // a localized representation of a list of items. 8166 SemaRef.Diag(Best->Function->getLocation(), 8167 diag::note_not_found_by_two_phase_lookup) 8168 << R.getLookupName() << 2; 8169 } 8170 8171 // Try to recover by calling this function. 8172 return true; 8173 } 8174 8175 R.clear(); 8176 } 8177 8178 return false; 8179} 8180 8181/// Attempt to recover from ill-formed use of a non-dependent operator in a 8182/// template, where the non-dependent operator was declared after the template 8183/// was defined. 8184/// 8185/// Returns true if a viable candidate was found and a diagnostic was issued. 8186static bool 8187DiagnoseTwoPhaseOperatorLookup(Sema &SemaRef, OverloadedOperatorKind Op, 8188 SourceLocation OpLoc, 8189 Expr **Args, unsigned NumArgs) { 8190 DeclarationName OpName = 8191 SemaRef.Context.DeclarationNames.getCXXOperatorName(Op); 8192 LookupResult R(SemaRef, OpName, OpLoc, Sema::LookupOperatorName); 8193 return DiagnoseTwoPhaseLookup(SemaRef, OpLoc, CXXScopeSpec(), R, 8194 /*ExplicitTemplateArgs=*/0, Args, NumArgs); 8195} 8196 8197/// Attempts to recover from a call where no functions were found. 8198/// 8199/// Returns true if new candidates were found. 8200static ExprResult 8201BuildRecoveryCallExpr(Sema &SemaRef, Scope *S, Expr *Fn, 8202 UnresolvedLookupExpr *ULE, 8203 SourceLocation LParenLoc, 8204 Expr **Args, unsigned NumArgs, 8205 SourceLocation RParenLoc, 8206 bool EmptyLookup) { 8207 8208 CXXScopeSpec SS; 8209 SS.Adopt(ULE->getQualifierLoc()); 8210 8211 TemplateArgumentListInfo TABuffer; 8212 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 8213 if (ULE->hasExplicitTemplateArgs()) { 8214 ULE->copyTemplateArgumentsInto(TABuffer); 8215 ExplicitTemplateArgs = &TABuffer; 8216 } 8217 8218 LookupResult R(SemaRef, ULE->getName(), ULE->getNameLoc(), 8219 Sema::LookupOrdinaryName); 8220 if (!DiagnoseTwoPhaseLookup(SemaRef, Fn->getExprLoc(), SS, R, 8221 ExplicitTemplateArgs, Args, NumArgs) && 8222 (!EmptyLookup || 8223 SemaRef.DiagnoseEmptyLookup(S, SS, R, Sema::CTC_Expression, 8224 ExplicitTemplateArgs, Args, NumArgs))) 8225 return ExprError(); 8226 8227 assert(!R.empty() && "lookup results empty despite recovery"); 8228 8229 // Build an implicit member call if appropriate. Just drop the 8230 // casts and such from the call, we don't really care. 8231 ExprResult NewFn = ExprError(); 8232 if ((*R.begin())->isCXXClassMember()) 8233 NewFn = SemaRef.BuildPossibleImplicitMemberExpr(SS, R, 8234 ExplicitTemplateArgs); 8235 else if (ExplicitTemplateArgs) 8236 NewFn = SemaRef.BuildTemplateIdExpr(SS, R, false, *ExplicitTemplateArgs); 8237 else 8238 NewFn = SemaRef.BuildDeclarationNameExpr(SS, R, false); 8239 8240 if (NewFn.isInvalid()) 8241 return ExprError(); 8242 8243 // This shouldn't cause an infinite loop because we're giving it 8244 // an expression with viable lookup results, which should never 8245 // end up here. 8246 return SemaRef.ActOnCallExpr(/*Scope*/ 0, NewFn.take(), LParenLoc, 8247 MultiExprArg(Args, NumArgs), RParenLoc); 8248} 8249 8250/// ResolveOverloadedCallFn - Given the call expression that calls Fn 8251/// (which eventually refers to the declaration Func) and the call 8252/// arguments Args/NumArgs, attempt to resolve the function call down 8253/// to a specific function. If overload resolution succeeds, returns 8254/// the function declaration produced by overload 8255/// resolution. Otherwise, emits diagnostics, deletes all of the 8256/// arguments and Fn, and returns NULL. 8257ExprResult 8258Sema::BuildOverloadedCallExpr(Scope *S, Expr *Fn, UnresolvedLookupExpr *ULE, 8259 SourceLocation LParenLoc, 8260 Expr **Args, unsigned NumArgs, 8261 SourceLocation RParenLoc, 8262 Expr *ExecConfig) { 8263#ifndef NDEBUG 8264 if (ULE->requiresADL()) { 8265 // To do ADL, we must have found an unqualified name. 8266 assert(!ULE->getQualifier() && "qualified name with ADL"); 8267 8268 // We don't perform ADL for implicit declarations of builtins. 8269 // Verify that this was correctly set up. 8270 FunctionDecl *F; 8271 if (ULE->decls_begin() + 1 == ULE->decls_end() && 8272 (F = dyn_cast<FunctionDecl>(*ULE->decls_begin())) && 8273 F->getBuiltinID() && F->isImplicit()) 8274 assert(0 && "performing ADL for builtin"); 8275 8276 // We don't perform ADL in C. 8277 assert(getLangOptions().CPlusPlus && "ADL enabled in C"); 8278 } else 8279 assert(!ULE->isStdAssociatedNamespace() && 8280 "std is associated namespace but not doing ADL"); 8281#endif 8282 8283 OverloadCandidateSet CandidateSet(Fn->getExprLoc()); 8284 8285 // Add the functions denoted by the callee to the set of candidate 8286 // functions, including those from argument-dependent lookup. 8287 AddOverloadedCallCandidates(ULE, Args, NumArgs, CandidateSet); 8288 8289 // If we found nothing, try to recover. 8290 // BuildRecoveryCallExpr diagnoses the error itself, so we just bail 8291 // out if it fails. 8292 if (CandidateSet.empty()) 8293 return BuildRecoveryCallExpr(*this, S, Fn, ULE, LParenLoc, Args, NumArgs, 8294 RParenLoc, /*EmptyLookup=*/true); 8295 8296 OverloadCandidateSet::iterator Best; 8297 switch (CandidateSet.BestViableFunction(*this, Fn->getLocStart(), Best)) { 8298 case OR_Success: { 8299 FunctionDecl *FDecl = Best->Function; 8300 MarkDeclarationReferenced(Fn->getExprLoc(), FDecl); 8301 CheckUnresolvedLookupAccess(ULE, Best->FoundDecl); 8302 DiagnoseUseOfDecl(FDecl? FDecl : Best->FoundDecl.getDecl(), 8303 ULE->getNameLoc()); 8304 Fn = FixOverloadedFunctionReference(Fn, Best->FoundDecl, FDecl); 8305 return BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, NumArgs, RParenLoc, 8306 ExecConfig); 8307 } 8308 8309 case OR_No_Viable_Function: { 8310 // Try to recover by looking for viable functions which the user might 8311 // have meant to call. 8312 ExprResult Recovery = BuildRecoveryCallExpr(*this, S, Fn, ULE, LParenLoc, 8313 Args, NumArgs, RParenLoc, 8314 /*EmptyLookup=*/false); 8315 if (!Recovery.isInvalid()) 8316 return Recovery; 8317 8318 Diag(Fn->getSourceRange().getBegin(), 8319 diag::err_ovl_no_viable_function_in_call) 8320 << ULE->getName() << Fn->getSourceRange(); 8321 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8322 break; 8323 } 8324 8325 case OR_Ambiguous: 8326 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_ambiguous_call) 8327 << ULE->getName() << Fn->getSourceRange(); 8328 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 8329 break; 8330 8331 case OR_Deleted: 8332 { 8333 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_deleted_call) 8334 << Best->Function->isDeleted() 8335 << ULE->getName() 8336 << getDeletedOrUnavailableSuffix(Best->Function) 8337 << Fn->getSourceRange(); 8338 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8339 } 8340 break; 8341 } 8342 8343 // Overload resolution failed. 8344 return ExprError(); 8345} 8346 8347static bool IsOverloaded(const UnresolvedSetImpl &Functions) { 8348 return Functions.size() > 1 || 8349 (Functions.size() == 1 && isa<FunctionTemplateDecl>(*Functions.begin())); 8350} 8351 8352/// \brief Create a unary operation that may resolve to an overloaded 8353/// operator. 8354/// 8355/// \param OpLoc The location of the operator itself (e.g., '*'). 8356/// 8357/// \param OpcIn The UnaryOperator::Opcode that describes this 8358/// operator. 8359/// 8360/// \param Functions The set of non-member functions that will be 8361/// considered by overload resolution. The caller needs to build this 8362/// set based on the context using, e.g., 8363/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 8364/// set should not contain any member functions; those will be added 8365/// by CreateOverloadedUnaryOp(). 8366/// 8367/// \param input The input argument. 8368ExprResult 8369Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, unsigned OpcIn, 8370 const UnresolvedSetImpl &Fns, 8371 Expr *Input) { 8372 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 8373 8374 OverloadedOperatorKind Op = UnaryOperator::getOverloadedOperator(Opc); 8375 assert(Op != OO_None && "Invalid opcode for overloaded unary operator"); 8376 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 8377 // TODO: provide better source location info. 8378 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 8379 8380 if (Input->getObjectKind() == OK_ObjCProperty) { 8381 ExprResult Result = ConvertPropertyForRValue(Input); 8382 if (Result.isInvalid()) 8383 return ExprError(); 8384 Input = Result.take(); 8385 } 8386 8387 Expr *Args[2] = { Input, 0 }; 8388 unsigned NumArgs = 1; 8389 8390 // For post-increment and post-decrement, add the implicit '0' as 8391 // the second argument, so that we know this is a post-increment or 8392 // post-decrement. 8393 if (Opc == UO_PostInc || Opc == UO_PostDec) { 8394 llvm::APSInt Zero(Context.getTypeSize(Context.IntTy), false); 8395 Args[1] = IntegerLiteral::Create(Context, Zero, Context.IntTy, 8396 SourceLocation()); 8397 NumArgs = 2; 8398 } 8399 8400 if (Input->isTypeDependent()) { 8401 if (Fns.empty()) 8402 return Owned(new (Context) UnaryOperator(Input, 8403 Opc, 8404 Context.DependentTy, 8405 VK_RValue, OK_Ordinary, 8406 OpLoc)); 8407 8408 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8409 UnresolvedLookupExpr *Fn 8410 = UnresolvedLookupExpr::Create(Context, NamingClass, 8411 NestedNameSpecifierLoc(), OpNameInfo, 8412 /*ADL*/ true, IsOverloaded(Fns), 8413 Fns.begin(), Fns.end()); 8414 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 8415 &Args[0], NumArgs, 8416 Context.DependentTy, 8417 VK_RValue, 8418 OpLoc)); 8419 } 8420 8421 // Build an empty overload set. 8422 OverloadCandidateSet CandidateSet(OpLoc); 8423 8424 // Add the candidates from the given function set. 8425 AddFunctionCandidates(Fns, &Args[0], NumArgs, CandidateSet, false); 8426 8427 // Add operator candidates that are member functions. 8428 AddMemberOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 8429 8430 // Add candidates from ADL. 8431 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 8432 Args, NumArgs, 8433 /*ExplicitTemplateArgs*/ 0, 8434 CandidateSet); 8435 8436 // Add builtin operator candidates. 8437 AddBuiltinOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 8438 8439 // Perform overload resolution. 8440 OverloadCandidateSet::iterator Best; 8441 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8442 case OR_Success: { 8443 // We found a built-in operator or an overloaded operator. 8444 FunctionDecl *FnDecl = Best->Function; 8445 8446 if (FnDecl) { 8447 // We matched an overloaded operator. Build a call to that 8448 // operator. 8449 8450 MarkDeclarationReferenced(OpLoc, FnDecl); 8451 8452 // Convert the arguments. 8453 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 8454 CheckMemberOperatorAccess(OpLoc, Args[0], 0, Best->FoundDecl); 8455 8456 ExprResult InputRes = 8457 PerformObjectArgumentInitialization(Input, /*Qualifier=*/0, 8458 Best->FoundDecl, Method); 8459 if (InputRes.isInvalid()) 8460 return ExprError(); 8461 Input = InputRes.take(); 8462 } else { 8463 // Convert the arguments. 8464 ExprResult InputInit 8465 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 8466 Context, 8467 FnDecl->getParamDecl(0)), 8468 SourceLocation(), 8469 Input); 8470 if (InputInit.isInvalid()) 8471 return ExprError(); 8472 Input = InputInit.take(); 8473 } 8474 8475 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 8476 8477 // Determine the result type. 8478 QualType ResultTy = FnDecl->getResultType(); 8479 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8480 ResultTy = ResultTy.getNonLValueExprType(Context); 8481 8482 // Build the actual expression node. 8483 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl); 8484 if (FnExpr.isInvalid()) 8485 return ExprError(); 8486 8487 Args[0] = Input; 8488 CallExpr *TheCall = 8489 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 8490 Args, NumArgs, ResultTy, VK, OpLoc); 8491 8492 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 8493 FnDecl)) 8494 return ExprError(); 8495 8496 return MaybeBindToTemporary(TheCall); 8497 } else { 8498 // We matched a built-in operator. Convert the arguments, then 8499 // break out so that we will build the appropriate built-in 8500 // operator node. 8501 ExprResult InputRes = 8502 PerformImplicitConversion(Input, Best->BuiltinTypes.ParamTypes[0], 8503 Best->Conversions[0], AA_Passing); 8504 if (InputRes.isInvalid()) 8505 return ExprError(); 8506 Input = InputRes.take(); 8507 break; 8508 } 8509 } 8510 8511 case OR_No_Viable_Function: 8512 // This is an erroneous use of an operator which can be overloaded by 8513 // a non-member function. Check for non-member operators which were 8514 // defined too late to be candidates. 8515 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, Args, NumArgs)) 8516 // FIXME: Recover by calling the found function. 8517 return ExprError(); 8518 8519 // No viable function; fall through to handling this as a 8520 // built-in operator, which will produce an error message for us. 8521 break; 8522 8523 case OR_Ambiguous: 8524 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 8525 << UnaryOperator::getOpcodeStr(Opc) 8526 << Input->getType() 8527 << Input->getSourceRange(); 8528 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, 8529 Args, NumArgs, 8530 UnaryOperator::getOpcodeStr(Opc), OpLoc); 8531 return ExprError(); 8532 8533 case OR_Deleted: 8534 Diag(OpLoc, diag::err_ovl_deleted_oper) 8535 << Best->Function->isDeleted() 8536 << UnaryOperator::getOpcodeStr(Opc) 8537 << getDeletedOrUnavailableSuffix(Best->Function) 8538 << Input->getSourceRange(); 8539 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8540 return ExprError(); 8541 } 8542 8543 // Either we found no viable overloaded operator or we matched a 8544 // built-in operator. In either case, fall through to trying to 8545 // build a built-in operation. 8546 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8547} 8548 8549/// \brief Create a binary operation that may resolve to an overloaded 8550/// operator. 8551/// 8552/// \param OpLoc The location of the operator itself (e.g., '+'). 8553/// 8554/// \param OpcIn The BinaryOperator::Opcode that describes this 8555/// operator. 8556/// 8557/// \param Functions The set of non-member functions that will be 8558/// considered by overload resolution. The caller needs to build this 8559/// set based on the context using, e.g., 8560/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 8561/// set should not contain any member functions; those will be added 8562/// by CreateOverloadedBinOp(). 8563/// 8564/// \param LHS Left-hand argument. 8565/// \param RHS Right-hand argument. 8566ExprResult 8567Sema::CreateOverloadedBinOp(SourceLocation OpLoc, 8568 unsigned OpcIn, 8569 const UnresolvedSetImpl &Fns, 8570 Expr *LHS, Expr *RHS) { 8571 Expr *Args[2] = { LHS, RHS }; 8572 LHS=RHS=0; //Please use only Args instead of LHS/RHS couple 8573 8574 BinaryOperator::Opcode Opc = static_cast<BinaryOperator::Opcode>(OpcIn); 8575 OverloadedOperatorKind Op = BinaryOperator::getOverloadedOperator(Opc); 8576 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 8577 8578 // If either side is type-dependent, create an appropriate dependent 8579 // expression. 8580 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 8581 if (Fns.empty()) { 8582 // If there are no functions to store, just build a dependent 8583 // BinaryOperator or CompoundAssignment. 8584 if (Opc <= BO_Assign || Opc > BO_OrAssign) 8585 return Owned(new (Context) BinaryOperator(Args[0], Args[1], Opc, 8586 Context.DependentTy, 8587 VK_RValue, OK_Ordinary, 8588 OpLoc)); 8589 8590 return Owned(new (Context) CompoundAssignOperator(Args[0], Args[1], Opc, 8591 Context.DependentTy, 8592 VK_LValue, 8593 OK_Ordinary, 8594 Context.DependentTy, 8595 Context.DependentTy, 8596 OpLoc)); 8597 } 8598 8599 // FIXME: save results of ADL from here? 8600 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8601 // TODO: provide better source location info in DNLoc component. 8602 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 8603 UnresolvedLookupExpr *Fn 8604 = UnresolvedLookupExpr::Create(Context, NamingClass, 8605 NestedNameSpecifierLoc(), OpNameInfo, 8606 /*ADL*/ true, IsOverloaded(Fns), 8607 Fns.begin(), Fns.end()); 8608 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 8609 Args, 2, 8610 Context.DependentTy, 8611 VK_RValue, 8612 OpLoc)); 8613 } 8614 8615 // Always do property rvalue conversions on the RHS. 8616 if (Args[1]->getObjectKind() == OK_ObjCProperty) { 8617 ExprResult Result = ConvertPropertyForRValue(Args[1]); 8618 if (Result.isInvalid()) 8619 return ExprError(); 8620 Args[1] = Result.take(); 8621 } 8622 8623 // The LHS is more complicated. 8624 if (Args[0]->getObjectKind() == OK_ObjCProperty) { 8625 8626 // There's a tension for assignment operators between primitive 8627 // property assignment and the overloaded operators. 8628 if (BinaryOperator::isAssignmentOp(Opc)) { 8629 const ObjCPropertyRefExpr *PRE = LHS->getObjCProperty(); 8630 8631 // Is the property "logically" settable? 8632 bool Settable = (PRE->isExplicitProperty() || 8633 PRE->getImplicitPropertySetter()); 8634 8635 // To avoid gratuitously inventing semantics, use the primitive 8636 // unless it isn't. Thoughts in case we ever really care: 8637 // - If the property isn't logically settable, we have to 8638 // load and hope. 8639 // - If the property is settable and this is simple assignment, 8640 // we really should use the primitive. 8641 // - If the property is settable, then we could try overloading 8642 // on a generic lvalue of the appropriate type; if it works 8643 // out to a builtin candidate, we would do that same operation 8644 // on the property, and otherwise just error. 8645 if (Settable) 8646 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8647 } 8648 8649 ExprResult Result = ConvertPropertyForRValue(Args[0]); 8650 if (Result.isInvalid()) 8651 return ExprError(); 8652 Args[0] = Result.take(); 8653 } 8654 8655 // If this is the assignment operator, we only perform overload resolution 8656 // if the left-hand side is a class or enumeration type. This is actually 8657 // a hack. The standard requires that we do overload resolution between the 8658 // various built-in candidates, but as DR507 points out, this can lead to 8659 // problems. So we do it this way, which pretty much follows what GCC does. 8660 // Note that we go the traditional code path for compound assignment forms. 8661 if (Opc == BO_Assign && !Args[0]->getType()->isOverloadableType()) 8662 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8663 8664 // If this is the .* operator, which is not overloadable, just 8665 // create a built-in binary operator. 8666 if (Opc == BO_PtrMemD) 8667 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8668 8669 // Build an empty overload set. 8670 OverloadCandidateSet CandidateSet(OpLoc); 8671 8672 // Add the candidates from the given function set. 8673 AddFunctionCandidates(Fns, Args, 2, CandidateSet, false); 8674 8675 // Add operator candidates that are member functions. 8676 AddMemberOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 8677 8678 // Add candidates from ADL. 8679 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 8680 Args, 2, 8681 /*ExplicitTemplateArgs*/ 0, 8682 CandidateSet); 8683 8684 // Add builtin operator candidates. 8685 AddBuiltinOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 8686 8687 // Perform overload resolution. 8688 OverloadCandidateSet::iterator Best; 8689 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8690 case OR_Success: { 8691 // We found a built-in operator or an overloaded operator. 8692 FunctionDecl *FnDecl = Best->Function; 8693 8694 if (FnDecl) { 8695 // We matched an overloaded operator. Build a call to that 8696 // operator. 8697 8698 MarkDeclarationReferenced(OpLoc, FnDecl); 8699 8700 // Convert the arguments. 8701 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 8702 // Best->Access is only meaningful for class members. 8703 CheckMemberOperatorAccess(OpLoc, Args[0], Args[1], Best->FoundDecl); 8704 8705 ExprResult Arg1 = 8706 PerformCopyInitialization( 8707 InitializedEntity::InitializeParameter(Context, 8708 FnDecl->getParamDecl(0)), 8709 SourceLocation(), Owned(Args[1])); 8710 if (Arg1.isInvalid()) 8711 return ExprError(); 8712 8713 ExprResult Arg0 = 8714 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 8715 Best->FoundDecl, Method); 8716 if (Arg0.isInvalid()) 8717 return ExprError(); 8718 Args[0] = Arg0.takeAs<Expr>(); 8719 Args[1] = RHS = Arg1.takeAs<Expr>(); 8720 } else { 8721 // Convert the arguments. 8722 ExprResult Arg0 = PerformCopyInitialization( 8723 InitializedEntity::InitializeParameter(Context, 8724 FnDecl->getParamDecl(0)), 8725 SourceLocation(), Owned(Args[0])); 8726 if (Arg0.isInvalid()) 8727 return ExprError(); 8728 8729 ExprResult Arg1 = 8730 PerformCopyInitialization( 8731 InitializedEntity::InitializeParameter(Context, 8732 FnDecl->getParamDecl(1)), 8733 SourceLocation(), Owned(Args[1])); 8734 if (Arg1.isInvalid()) 8735 return ExprError(); 8736 Args[0] = LHS = Arg0.takeAs<Expr>(); 8737 Args[1] = RHS = Arg1.takeAs<Expr>(); 8738 } 8739 8740 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 8741 8742 // Determine the result type. 8743 QualType ResultTy = FnDecl->getResultType(); 8744 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8745 ResultTy = ResultTy.getNonLValueExprType(Context); 8746 8747 // Build the actual expression node. 8748 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, OpLoc); 8749 if (FnExpr.isInvalid()) 8750 return ExprError(); 8751 8752 CXXOperatorCallExpr *TheCall = 8753 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 8754 Args, 2, ResultTy, VK, OpLoc); 8755 8756 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 8757 FnDecl)) 8758 return ExprError(); 8759 8760 return MaybeBindToTemporary(TheCall); 8761 } else { 8762 // We matched a built-in operator. Convert the arguments, then 8763 // break out so that we will build the appropriate built-in 8764 // operator node. 8765 ExprResult ArgsRes0 = 8766 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 8767 Best->Conversions[0], AA_Passing); 8768 if (ArgsRes0.isInvalid()) 8769 return ExprError(); 8770 Args[0] = ArgsRes0.take(); 8771 8772 ExprResult ArgsRes1 = 8773 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 8774 Best->Conversions[1], AA_Passing); 8775 if (ArgsRes1.isInvalid()) 8776 return ExprError(); 8777 Args[1] = ArgsRes1.take(); 8778 break; 8779 } 8780 } 8781 8782 case OR_No_Viable_Function: { 8783 // C++ [over.match.oper]p9: 8784 // If the operator is the operator , [...] and there are no 8785 // viable functions, then the operator is assumed to be the 8786 // built-in operator and interpreted according to clause 5. 8787 if (Opc == BO_Comma) 8788 break; 8789 8790 // For class as left operand for assignment or compound assigment 8791 // operator do not fall through to handling in built-in, but report that 8792 // no overloaded assignment operator found 8793 ExprResult Result = ExprError(); 8794 if (Args[0]->getType()->isRecordType() && 8795 Opc >= BO_Assign && Opc <= BO_OrAssign) { 8796 Diag(OpLoc, diag::err_ovl_no_viable_oper) 8797 << BinaryOperator::getOpcodeStr(Opc) 8798 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8799 } else { 8800 // This is an erroneous use of an operator which can be overloaded by 8801 // a non-member function. Check for non-member operators which were 8802 // defined too late to be candidates. 8803 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, Args, 2)) 8804 // FIXME: Recover by calling the found function. 8805 return ExprError(); 8806 8807 // No viable function; try to create a built-in operation, which will 8808 // produce an error. Then, show the non-viable candidates. 8809 Result = CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8810 } 8811 assert(Result.isInvalid() && 8812 "C++ binary operator overloading is missing candidates!"); 8813 if (Result.isInvalid()) 8814 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8815 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8816 return move(Result); 8817 } 8818 8819 case OR_Ambiguous: 8820 Diag(OpLoc, diag::err_ovl_ambiguous_oper_binary) 8821 << BinaryOperator::getOpcodeStr(Opc) 8822 << Args[0]->getType() << Args[1]->getType() 8823 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8824 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 8825 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8826 return ExprError(); 8827 8828 case OR_Deleted: 8829 Diag(OpLoc, diag::err_ovl_deleted_oper) 8830 << Best->Function->isDeleted() 8831 << BinaryOperator::getOpcodeStr(Opc) 8832 << getDeletedOrUnavailableSuffix(Best->Function) 8833 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8834 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2); 8835 return ExprError(); 8836 } 8837 8838 // We matched a built-in operator; build it. 8839 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8840} 8841 8842ExprResult 8843Sema::CreateOverloadedArraySubscriptExpr(SourceLocation LLoc, 8844 SourceLocation RLoc, 8845 Expr *Base, Expr *Idx) { 8846 Expr *Args[2] = { Base, Idx }; 8847 DeclarationName OpName = 8848 Context.DeclarationNames.getCXXOperatorName(OO_Subscript); 8849 8850 // If either side is type-dependent, create an appropriate dependent 8851 // expression. 8852 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 8853 8854 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8855 // CHECKME: no 'operator' keyword? 8856 DeclarationNameInfo OpNameInfo(OpName, LLoc); 8857 OpNameInfo.setCXXOperatorNameRange(SourceRange(LLoc, RLoc)); 8858 UnresolvedLookupExpr *Fn 8859 = UnresolvedLookupExpr::Create(Context, NamingClass, 8860 NestedNameSpecifierLoc(), OpNameInfo, 8861 /*ADL*/ true, /*Overloaded*/ false, 8862 UnresolvedSetIterator(), 8863 UnresolvedSetIterator()); 8864 // Can't add any actual overloads yet 8865 8866 return Owned(new (Context) CXXOperatorCallExpr(Context, OO_Subscript, Fn, 8867 Args, 2, 8868 Context.DependentTy, 8869 VK_RValue, 8870 RLoc)); 8871 } 8872 8873 if (Args[0]->getObjectKind() == OK_ObjCProperty) { 8874 ExprResult Result = ConvertPropertyForRValue(Args[0]); 8875 if (Result.isInvalid()) 8876 return ExprError(); 8877 Args[0] = Result.take(); 8878 } 8879 if (Args[1]->getObjectKind() == OK_ObjCProperty) { 8880 ExprResult Result = ConvertPropertyForRValue(Args[1]); 8881 if (Result.isInvalid()) 8882 return ExprError(); 8883 Args[1] = Result.take(); 8884 } 8885 8886 // Build an empty overload set. 8887 OverloadCandidateSet CandidateSet(LLoc); 8888 8889 // Subscript can only be overloaded as a member function. 8890 8891 // Add operator candidates that are member functions. 8892 AddMemberOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 8893 8894 // Add builtin operator candidates. 8895 AddBuiltinOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 8896 8897 // Perform overload resolution. 8898 OverloadCandidateSet::iterator Best; 8899 switch (CandidateSet.BestViableFunction(*this, LLoc, Best)) { 8900 case OR_Success: { 8901 // We found a built-in operator or an overloaded operator. 8902 FunctionDecl *FnDecl = Best->Function; 8903 8904 if (FnDecl) { 8905 // We matched an overloaded operator. Build a call to that 8906 // operator. 8907 8908 MarkDeclarationReferenced(LLoc, FnDecl); 8909 8910 CheckMemberOperatorAccess(LLoc, Args[0], Args[1], Best->FoundDecl); 8911 DiagnoseUseOfDecl(Best->FoundDecl, LLoc); 8912 8913 // Convert the arguments. 8914 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 8915 ExprResult Arg0 = 8916 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 8917 Best->FoundDecl, Method); 8918 if (Arg0.isInvalid()) 8919 return ExprError(); 8920 Args[0] = Arg0.take(); 8921 8922 // Convert the arguments. 8923 ExprResult InputInit 8924 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 8925 Context, 8926 FnDecl->getParamDecl(0)), 8927 SourceLocation(), 8928 Owned(Args[1])); 8929 if (InputInit.isInvalid()) 8930 return ExprError(); 8931 8932 Args[1] = InputInit.takeAs<Expr>(); 8933 8934 // Determine the result type 8935 QualType ResultTy = FnDecl->getResultType(); 8936 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8937 ResultTy = ResultTy.getNonLValueExprType(Context); 8938 8939 // Build the actual expression node. 8940 DeclarationNameLoc LocInfo; 8941 LocInfo.CXXOperatorName.BeginOpNameLoc = LLoc.getRawEncoding(); 8942 LocInfo.CXXOperatorName.EndOpNameLoc = RLoc.getRawEncoding(); 8943 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, LLoc, LocInfo); 8944 if (FnExpr.isInvalid()) 8945 return ExprError(); 8946 8947 CXXOperatorCallExpr *TheCall = 8948 new (Context) CXXOperatorCallExpr(Context, OO_Subscript, 8949 FnExpr.take(), Args, 2, 8950 ResultTy, VK, RLoc); 8951 8952 if (CheckCallReturnType(FnDecl->getResultType(), LLoc, TheCall, 8953 FnDecl)) 8954 return ExprError(); 8955 8956 return MaybeBindToTemporary(TheCall); 8957 } else { 8958 // We matched a built-in operator. Convert the arguments, then 8959 // break out so that we will build the appropriate built-in 8960 // operator node. 8961 ExprResult ArgsRes0 = 8962 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 8963 Best->Conversions[0], AA_Passing); 8964 if (ArgsRes0.isInvalid()) 8965 return ExprError(); 8966 Args[0] = ArgsRes0.take(); 8967 8968 ExprResult ArgsRes1 = 8969 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 8970 Best->Conversions[1], AA_Passing); 8971 if (ArgsRes1.isInvalid()) 8972 return ExprError(); 8973 Args[1] = ArgsRes1.take(); 8974 8975 break; 8976 } 8977 } 8978 8979 case OR_No_Viable_Function: { 8980 if (CandidateSet.empty()) 8981 Diag(LLoc, diag::err_ovl_no_oper) 8982 << Args[0]->getType() << /*subscript*/ 0 8983 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8984 else 8985 Diag(LLoc, diag::err_ovl_no_viable_subscript) 8986 << Args[0]->getType() 8987 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8988 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8989 "[]", LLoc); 8990 return ExprError(); 8991 } 8992 8993 case OR_Ambiguous: 8994 Diag(LLoc, diag::err_ovl_ambiguous_oper_binary) 8995 << "[]" 8996 << Args[0]->getType() << Args[1]->getType() 8997 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8998 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 8999 "[]", LLoc); 9000 return ExprError(); 9001 9002 case OR_Deleted: 9003 Diag(LLoc, diag::err_ovl_deleted_oper) 9004 << Best->Function->isDeleted() << "[]" 9005 << getDeletedOrUnavailableSuffix(Best->Function) 9006 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9007 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 9008 "[]", LLoc); 9009 return ExprError(); 9010 } 9011 9012 // We matched a built-in operator; build it. 9013 return CreateBuiltinArraySubscriptExpr(Args[0], LLoc, Args[1], RLoc); 9014} 9015 9016/// BuildCallToMemberFunction - Build a call to a member 9017/// function. MemExpr is the expression that refers to the member 9018/// function (and includes the object parameter), Args/NumArgs are the 9019/// arguments to the function call (not including the object 9020/// parameter). The caller needs to validate that the member 9021/// expression refers to a non-static member function or an overloaded 9022/// member function. 9023ExprResult 9024Sema::BuildCallToMemberFunction(Scope *S, Expr *MemExprE, 9025 SourceLocation LParenLoc, Expr **Args, 9026 unsigned NumArgs, SourceLocation RParenLoc) { 9027 assert(MemExprE->getType() == Context.BoundMemberTy || 9028 MemExprE->getType() == Context.OverloadTy); 9029 9030 // Dig out the member expression. This holds both the object 9031 // argument and the member function we're referring to. 9032 Expr *NakedMemExpr = MemExprE->IgnoreParens(); 9033 9034 // Determine whether this is a call to a pointer-to-member function. 9035 if (BinaryOperator *op = dyn_cast<BinaryOperator>(NakedMemExpr)) { 9036 assert(op->getType() == Context.BoundMemberTy); 9037 assert(op->getOpcode() == BO_PtrMemD || op->getOpcode() == BO_PtrMemI); 9038 9039 QualType fnType = 9040 op->getRHS()->getType()->castAs<MemberPointerType>()->getPointeeType(); 9041 9042 const FunctionProtoType *proto = fnType->castAs<FunctionProtoType>(); 9043 QualType resultType = proto->getCallResultType(Context); 9044 ExprValueKind valueKind = Expr::getValueKindForType(proto->getResultType()); 9045 9046 // Check that the object type isn't more qualified than the 9047 // member function we're calling. 9048 Qualifiers funcQuals = Qualifiers::fromCVRMask(proto->getTypeQuals()); 9049 9050 QualType objectType = op->getLHS()->getType(); 9051 if (op->getOpcode() == BO_PtrMemI) 9052 objectType = objectType->castAs<PointerType>()->getPointeeType(); 9053 Qualifiers objectQuals = objectType.getQualifiers(); 9054 9055 Qualifiers difference = objectQuals - funcQuals; 9056 difference.removeObjCGCAttr(); 9057 difference.removeAddressSpace(); 9058 if (difference) { 9059 std::string qualsString = difference.getAsString(); 9060 Diag(LParenLoc, diag::err_pointer_to_member_call_drops_quals) 9061 << fnType.getUnqualifiedType() 9062 << qualsString 9063 << (qualsString.find(' ') == std::string::npos ? 1 : 2); 9064 } 9065 9066 CXXMemberCallExpr *call 9067 = new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 9068 resultType, valueKind, RParenLoc); 9069 9070 if (CheckCallReturnType(proto->getResultType(), 9071 op->getRHS()->getSourceRange().getBegin(), 9072 call, 0)) 9073 return ExprError(); 9074 9075 if (ConvertArgumentsForCall(call, op, 0, proto, Args, NumArgs, RParenLoc)) 9076 return ExprError(); 9077 9078 return MaybeBindToTemporary(call); 9079 } 9080 9081 MemberExpr *MemExpr; 9082 CXXMethodDecl *Method = 0; 9083 DeclAccessPair FoundDecl = DeclAccessPair::make(0, AS_public); 9084 NestedNameSpecifier *Qualifier = 0; 9085 if (isa<MemberExpr>(NakedMemExpr)) { 9086 MemExpr = cast<MemberExpr>(NakedMemExpr); 9087 Method = cast<CXXMethodDecl>(MemExpr->getMemberDecl()); 9088 FoundDecl = MemExpr->getFoundDecl(); 9089 Qualifier = MemExpr->getQualifier(); 9090 } else { 9091 UnresolvedMemberExpr *UnresExpr = cast<UnresolvedMemberExpr>(NakedMemExpr); 9092 Qualifier = UnresExpr->getQualifier(); 9093 9094 QualType ObjectType = UnresExpr->getBaseType(); 9095 Expr::Classification ObjectClassification 9096 = UnresExpr->isArrow()? Expr::Classification::makeSimpleLValue() 9097 : UnresExpr->getBase()->Classify(Context); 9098 9099 // Add overload candidates 9100 OverloadCandidateSet CandidateSet(UnresExpr->getMemberLoc()); 9101 9102 // FIXME: avoid copy. 9103 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9104 if (UnresExpr->hasExplicitTemplateArgs()) { 9105 UnresExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 9106 TemplateArgs = &TemplateArgsBuffer; 9107 } 9108 9109 for (UnresolvedMemberExpr::decls_iterator I = UnresExpr->decls_begin(), 9110 E = UnresExpr->decls_end(); I != E; ++I) { 9111 9112 NamedDecl *Func = *I; 9113 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(Func->getDeclContext()); 9114 if (isa<UsingShadowDecl>(Func)) 9115 Func = cast<UsingShadowDecl>(Func)->getTargetDecl(); 9116 9117 9118 // Microsoft supports direct constructor calls. 9119 if (getLangOptions().Microsoft && isa<CXXConstructorDecl>(Func)) { 9120 AddOverloadCandidate(cast<CXXConstructorDecl>(Func), I.getPair(), Args, NumArgs, 9121 CandidateSet); 9122 } else if ((Method = dyn_cast<CXXMethodDecl>(Func))) { 9123 // If explicit template arguments were provided, we can't call a 9124 // non-template member function. 9125 if (TemplateArgs) 9126 continue; 9127 9128 AddMethodCandidate(Method, I.getPair(), ActingDC, ObjectType, 9129 ObjectClassification, 9130 Args, NumArgs, CandidateSet, 9131 /*SuppressUserConversions=*/false); 9132 } else { 9133 AddMethodTemplateCandidate(cast<FunctionTemplateDecl>(Func), 9134 I.getPair(), ActingDC, TemplateArgs, 9135 ObjectType, ObjectClassification, 9136 Args, NumArgs, CandidateSet, 9137 /*SuppressUsedConversions=*/false); 9138 } 9139 } 9140 9141 DeclarationName DeclName = UnresExpr->getMemberName(); 9142 9143 OverloadCandidateSet::iterator Best; 9144 switch (CandidateSet.BestViableFunction(*this, UnresExpr->getLocStart(), 9145 Best)) { 9146 case OR_Success: 9147 Method = cast<CXXMethodDecl>(Best->Function); 9148 MarkDeclarationReferenced(UnresExpr->getMemberLoc(), Method); 9149 FoundDecl = Best->FoundDecl; 9150 CheckUnresolvedMemberAccess(UnresExpr, Best->FoundDecl); 9151 DiagnoseUseOfDecl(Best->FoundDecl, UnresExpr->getNameLoc()); 9152 break; 9153 9154 case OR_No_Viable_Function: 9155 Diag(UnresExpr->getMemberLoc(), 9156 diag::err_ovl_no_viable_member_function_in_call) 9157 << DeclName << MemExprE->getSourceRange(); 9158 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9159 // FIXME: Leaking incoming expressions! 9160 return ExprError(); 9161 9162 case OR_Ambiguous: 9163 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_ambiguous_member_call) 9164 << DeclName << MemExprE->getSourceRange(); 9165 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9166 // FIXME: Leaking incoming expressions! 9167 return ExprError(); 9168 9169 case OR_Deleted: 9170 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_deleted_member_call) 9171 << Best->Function->isDeleted() 9172 << DeclName 9173 << getDeletedOrUnavailableSuffix(Best->Function) 9174 << MemExprE->getSourceRange(); 9175 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9176 // FIXME: Leaking incoming expressions! 9177 return ExprError(); 9178 } 9179 9180 MemExprE = FixOverloadedFunctionReference(MemExprE, FoundDecl, Method); 9181 9182 // If overload resolution picked a static member, build a 9183 // non-member call based on that function. 9184 if (Method->isStatic()) { 9185 return BuildResolvedCallExpr(MemExprE, Method, LParenLoc, 9186 Args, NumArgs, RParenLoc); 9187 } 9188 9189 MemExpr = cast<MemberExpr>(MemExprE->IgnoreParens()); 9190 } 9191 9192 QualType ResultType = Method->getResultType(); 9193 ExprValueKind VK = Expr::getValueKindForType(ResultType); 9194 ResultType = ResultType.getNonLValueExprType(Context); 9195 9196 assert(Method && "Member call to something that isn't a method?"); 9197 CXXMemberCallExpr *TheCall = 9198 new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 9199 ResultType, VK, RParenLoc); 9200 9201 // Check for a valid return type. 9202 if (CheckCallReturnType(Method->getResultType(), MemExpr->getMemberLoc(), 9203 TheCall, Method)) 9204 return ExprError(); 9205 9206 // Convert the object argument (for a non-static member function call). 9207 // We only need to do this if there was actually an overload; otherwise 9208 // it was done at lookup. 9209 if (!Method->isStatic()) { 9210 ExprResult ObjectArg = 9211 PerformObjectArgumentInitialization(MemExpr->getBase(), Qualifier, 9212 FoundDecl, Method); 9213 if (ObjectArg.isInvalid()) 9214 return ExprError(); 9215 MemExpr->setBase(ObjectArg.take()); 9216 } 9217 9218 // Convert the rest of the arguments 9219 const FunctionProtoType *Proto = 9220 Method->getType()->getAs<FunctionProtoType>(); 9221 if (ConvertArgumentsForCall(TheCall, MemExpr, Method, Proto, Args, NumArgs, 9222 RParenLoc)) 9223 return ExprError(); 9224 9225 if (CheckFunctionCall(Method, TheCall)) 9226 return ExprError(); 9227 9228 if ((isa<CXXConstructorDecl>(CurContext) || 9229 isa<CXXDestructorDecl>(CurContext)) && 9230 TheCall->getMethodDecl()->isPure()) { 9231 const CXXMethodDecl *MD = TheCall->getMethodDecl(); 9232 9233 if (isa<CXXThisExpr>(MemExpr->getBase()->IgnoreParenCasts())) { 9234 Diag(MemExpr->getLocStart(), 9235 diag::warn_call_to_pure_virtual_member_function_from_ctor_dtor) 9236 << MD->getDeclName() << isa<CXXDestructorDecl>(CurContext) 9237 << MD->getParent()->getDeclName(); 9238 9239 Diag(MD->getLocStart(), diag::note_previous_decl) << MD->getDeclName(); 9240 } 9241 } 9242 return MaybeBindToTemporary(TheCall); 9243} 9244 9245/// BuildCallToObjectOfClassType - Build a call to an object of class 9246/// type (C++ [over.call.object]), which can end up invoking an 9247/// overloaded function call operator (@c operator()) or performing a 9248/// user-defined conversion on the object argument. 9249ExprResult 9250Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj, 9251 SourceLocation LParenLoc, 9252 Expr **Args, unsigned NumArgs, 9253 SourceLocation RParenLoc) { 9254 ExprResult Object = Owned(Obj); 9255 if (Object.get()->getObjectKind() == OK_ObjCProperty) { 9256 Object = ConvertPropertyForRValue(Object.take()); 9257 if (Object.isInvalid()) 9258 return ExprError(); 9259 } 9260 9261 assert(Object.get()->getType()->isRecordType() && "Requires object type argument"); 9262 const RecordType *Record = Object.get()->getType()->getAs<RecordType>(); 9263 9264 // C++ [over.call.object]p1: 9265 // If the primary-expression E in the function call syntax 9266 // evaluates to a class object of type "cv T", then the set of 9267 // candidate functions includes at least the function call 9268 // operators of T. The function call operators of T are obtained by 9269 // ordinary lookup of the name operator() in the context of 9270 // (E).operator(). 9271 OverloadCandidateSet CandidateSet(LParenLoc); 9272 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(OO_Call); 9273 9274 if (RequireCompleteType(LParenLoc, Object.get()->getType(), 9275 PDiag(diag::err_incomplete_object_call) 9276 << Object.get()->getSourceRange())) 9277 return true; 9278 9279 LookupResult R(*this, OpName, LParenLoc, LookupOrdinaryName); 9280 LookupQualifiedName(R, Record->getDecl()); 9281 R.suppressDiagnostics(); 9282 9283 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 9284 Oper != OperEnd; ++Oper) { 9285 AddMethodCandidate(Oper.getPair(), Object.get()->getType(), 9286 Object.get()->Classify(Context), Args, NumArgs, CandidateSet, 9287 /*SuppressUserConversions=*/ false); 9288 } 9289 9290 // C++ [over.call.object]p2: 9291 // In addition, for each (non-explicit in C++0x) conversion function 9292 // declared in T of the form 9293 // 9294 // operator conversion-type-id () cv-qualifier; 9295 // 9296 // where cv-qualifier is the same cv-qualification as, or a 9297 // greater cv-qualification than, cv, and where conversion-type-id 9298 // denotes the type "pointer to function of (P1,...,Pn) returning 9299 // R", or the type "reference to pointer to function of 9300 // (P1,...,Pn) returning R", or the type "reference to function 9301 // of (P1,...,Pn) returning R", a surrogate call function [...] 9302 // is also considered as a candidate function. Similarly, 9303 // surrogate call functions are added to the set of candidate 9304 // functions for each conversion function declared in an 9305 // accessible base class provided the function is not hidden 9306 // within T by another intervening declaration. 9307 const UnresolvedSetImpl *Conversions 9308 = cast<CXXRecordDecl>(Record->getDecl())->getVisibleConversionFunctions(); 9309 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 9310 E = Conversions->end(); I != E; ++I) { 9311 NamedDecl *D = *I; 9312 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 9313 if (isa<UsingShadowDecl>(D)) 9314 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 9315 9316 // Skip over templated conversion functions; they aren't 9317 // surrogates. 9318 if (isa<FunctionTemplateDecl>(D)) 9319 continue; 9320 9321 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 9322 if (!Conv->isExplicit()) { 9323 // Strip the reference type (if any) and then the pointer type (if 9324 // any) to get down to what might be a function type. 9325 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 9326 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 9327 ConvType = ConvPtrType->getPointeeType(); 9328 9329 if (const FunctionProtoType *Proto = ConvType->getAs<FunctionProtoType>()) 9330 { 9331 AddSurrogateCandidate(Conv, I.getPair(), ActingContext, Proto, 9332 Object.get(), Args, NumArgs, CandidateSet); 9333 } 9334 } 9335 } 9336 9337 // Perform overload resolution. 9338 OverloadCandidateSet::iterator Best; 9339 switch (CandidateSet.BestViableFunction(*this, Object.get()->getLocStart(), 9340 Best)) { 9341 case OR_Success: 9342 // Overload resolution succeeded; we'll build the appropriate call 9343 // below. 9344 break; 9345 9346 case OR_No_Viable_Function: 9347 if (CandidateSet.empty()) 9348 Diag(Object.get()->getSourceRange().getBegin(), diag::err_ovl_no_oper) 9349 << Object.get()->getType() << /*call*/ 1 9350 << Object.get()->getSourceRange(); 9351 else 9352 Diag(Object.get()->getSourceRange().getBegin(), 9353 diag::err_ovl_no_viable_object_call) 9354 << Object.get()->getType() << Object.get()->getSourceRange(); 9355 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9356 break; 9357 9358 case OR_Ambiguous: 9359 Diag(Object.get()->getSourceRange().getBegin(), 9360 diag::err_ovl_ambiguous_object_call) 9361 << Object.get()->getType() << Object.get()->getSourceRange(); 9362 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 9363 break; 9364 9365 case OR_Deleted: 9366 Diag(Object.get()->getSourceRange().getBegin(), 9367 diag::err_ovl_deleted_object_call) 9368 << Best->Function->isDeleted() 9369 << Object.get()->getType() 9370 << getDeletedOrUnavailableSuffix(Best->Function) 9371 << Object.get()->getSourceRange(); 9372 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9373 break; 9374 } 9375 9376 if (Best == CandidateSet.end()) 9377 return true; 9378 9379 if (Best->Function == 0) { 9380 // Since there is no function declaration, this is one of the 9381 // surrogate candidates. Dig out the conversion function. 9382 CXXConversionDecl *Conv 9383 = cast<CXXConversionDecl>( 9384 Best->Conversions[0].UserDefined.ConversionFunction); 9385 9386 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 9387 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 9388 9389 // We selected one of the surrogate functions that converts the 9390 // object parameter to a function pointer. Perform the conversion 9391 // on the object argument, then let ActOnCallExpr finish the job. 9392 9393 // Create an implicit member expr to refer to the conversion operator. 9394 // and then call it. 9395 ExprResult Call = BuildCXXMemberCallExpr(Object.get(), Best->FoundDecl, Conv); 9396 if (Call.isInvalid()) 9397 return ExprError(); 9398 9399 return ActOnCallExpr(S, Call.get(), LParenLoc, MultiExprArg(Args, NumArgs), 9400 RParenLoc); 9401 } 9402 9403 MarkDeclarationReferenced(LParenLoc, Best->Function); 9404 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 9405 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 9406 9407 // We found an overloaded operator(). Build a CXXOperatorCallExpr 9408 // that calls this method, using Object for the implicit object 9409 // parameter and passing along the remaining arguments. 9410 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 9411 const FunctionProtoType *Proto = 9412 Method->getType()->getAs<FunctionProtoType>(); 9413 9414 unsigned NumArgsInProto = Proto->getNumArgs(); 9415 unsigned NumArgsToCheck = NumArgs; 9416 9417 // Build the full argument list for the method call (the 9418 // implicit object parameter is placed at the beginning of the 9419 // list). 9420 Expr **MethodArgs; 9421 if (NumArgs < NumArgsInProto) { 9422 NumArgsToCheck = NumArgsInProto; 9423 MethodArgs = new Expr*[NumArgsInProto + 1]; 9424 } else { 9425 MethodArgs = new Expr*[NumArgs + 1]; 9426 } 9427 MethodArgs[0] = Object.get(); 9428 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 9429 MethodArgs[ArgIdx + 1] = Args[ArgIdx]; 9430 9431 ExprResult NewFn = CreateFunctionRefExpr(*this, Method); 9432 if (NewFn.isInvalid()) 9433 return true; 9434 9435 // Once we've built TheCall, all of the expressions are properly 9436 // owned. 9437 QualType ResultTy = Method->getResultType(); 9438 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9439 ResultTy = ResultTy.getNonLValueExprType(Context); 9440 9441 CXXOperatorCallExpr *TheCall = 9442 new (Context) CXXOperatorCallExpr(Context, OO_Call, NewFn.take(), 9443 MethodArgs, NumArgs + 1, 9444 ResultTy, VK, RParenLoc); 9445 delete [] MethodArgs; 9446 9447 if (CheckCallReturnType(Method->getResultType(), LParenLoc, TheCall, 9448 Method)) 9449 return true; 9450 9451 // We may have default arguments. If so, we need to allocate more 9452 // slots in the call for them. 9453 if (NumArgs < NumArgsInProto) 9454 TheCall->setNumArgs(Context, NumArgsInProto + 1); 9455 else if (NumArgs > NumArgsInProto) 9456 NumArgsToCheck = NumArgsInProto; 9457 9458 bool IsError = false; 9459 9460 // Initialize the implicit object parameter. 9461 ExprResult ObjRes = 9462 PerformObjectArgumentInitialization(Object.get(), /*Qualifier=*/0, 9463 Best->FoundDecl, Method); 9464 if (ObjRes.isInvalid()) 9465 IsError = true; 9466 else 9467 Object = move(ObjRes); 9468 TheCall->setArg(0, Object.take()); 9469 9470 // Check the argument types. 9471 for (unsigned i = 0; i != NumArgsToCheck; i++) { 9472 Expr *Arg; 9473 if (i < NumArgs) { 9474 Arg = Args[i]; 9475 9476 // Pass the argument. 9477 9478 ExprResult InputInit 9479 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 9480 Context, 9481 Method->getParamDecl(i)), 9482 SourceLocation(), Arg); 9483 9484 IsError |= InputInit.isInvalid(); 9485 Arg = InputInit.takeAs<Expr>(); 9486 } else { 9487 ExprResult DefArg 9488 = BuildCXXDefaultArgExpr(LParenLoc, Method, Method->getParamDecl(i)); 9489 if (DefArg.isInvalid()) { 9490 IsError = true; 9491 break; 9492 } 9493 9494 Arg = DefArg.takeAs<Expr>(); 9495 } 9496 9497 TheCall->setArg(i + 1, Arg); 9498 } 9499 9500 // If this is a variadic call, handle args passed through "...". 9501 if (Proto->isVariadic()) { 9502 // Promote the arguments (C99 6.5.2.2p7). 9503 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 9504 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], VariadicMethod, 0); 9505 IsError |= Arg.isInvalid(); 9506 TheCall->setArg(i + 1, Arg.take()); 9507 } 9508 } 9509 9510 if (IsError) return true; 9511 9512 if (CheckFunctionCall(Method, TheCall)) 9513 return true; 9514 9515 return MaybeBindToTemporary(TheCall); 9516} 9517 9518/// BuildOverloadedArrowExpr - Build a call to an overloaded @c operator-> 9519/// (if one exists), where @c Base is an expression of class type and 9520/// @c Member is the name of the member we're trying to find. 9521ExprResult 9522Sema::BuildOverloadedArrowExpr(Scope *S, Expr *Base, SourceLocation OpLoc) { 9523 assert(Base->getType()->isRecordType() && 9524 "left-hand side must have class type"); 9525 9526 if (Base->getObjectKind() == OK_ObjCProperty) { 9527 ExprResult Result = ConvertPropertyForRValue(Base); 9528 if (Result.isInvalid()) 9529 return ExprError(); 9530 Base = Result.take(); 9531 } 9532 9533 SourceLocation Loc = Base->getExprLoc(); 9534 9535 // C++ [over.ref]p1: 9536 // 9537 // [...] An expression x->m is interpreted as (x.operator->())->m 9538 // for a class object x of type T if T::operator->() exists and if 9539 // the operator is selected as the best match function by the 9540 // overload resolution mechanism (13.3). 9541 DeclarationName OpName = 9542 Context.DeclarationNames.getCXXOperatorName(OO_Arrow); 9543 OverloadCandidateSet CandidateSet(Loc); 9544 const RecordType *BaseRecord = Base->getType()->getAs<RecordType>(); 9545 9546 if (RequireCompleteType(Loc, Base->getType(), 9547 PDiag(diag::err_typecheck_incomplete_tag) 9548 << Base->getSourceRange())) 9549 return ExprError(); 9550 9551 LookupResult R(*this, OpName, OpLoc, LookupOrdinaryName); 9552 LookupQualifiedName(R, BaseRecord->getDecl()); 9553 R.suppressDiagnostics(); 9554 9555 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 9556 Oper != OperEnd; ++Oper) { 9557 AddMethodCandidate(Oper.getPair(), Base->getType(), Base->Classify(Context), 9558 0, 0, CandidateSet, /*SuppressUserConversions=*/false); 9559 } 9560 9561 // Perform overload resolution. 9562 OverloadCandidateSet::iterator Best; 9563 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 9564 case OR_Success: 9565 // Overload resolution succeeded; we'll build the call below. 9566 break; 9567 9568 case OR_No_Viable_Function: 9569 if (CandidateSet.empty()) 9570 Diag(OpLoc, diag::err_typecheck_member_reference_arrow) 9571 << Base->getType() << Base->getSourceRange(); 9572 else 9573 Diag(OpLoc, diag::err_ovl_no_viable_oper) 9574 << "operator->" << Base->getSourceRange(); 9575 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 9576 return ExprError(); 9577 9578 case OR_Ambiguous: 9579 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 9580 << "->" << Base->getType() << Base->getSourceRange(); 9581 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, &Base, 1); 9582 return ExprError(); 9583 9584 case OR_Deleted: 9585 Diag(OpLoc, diag::err_ovl_deleted_oper) 9586 << Best->Function->isDeleted() 9587 << "->" 9588 << getDeletedOrUnavailableSuffix(Best->Function) 9589 << Base->getSourceRange(); 9590 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 9591 return ExprError(); 9592 } 9593 9594 MarkDeclarationReferenced(OpLoc, Best->Function); 9595 CheckMemberOperatorAccess(OpLoc, Base, 0, Best->FoundDecl); 9596 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 9597 9598 // Convert the object parameter. 9599 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 9600 ExprResult BaseResult = 9601 PerformObjectArgumentInitialization(Base, /*Qualifier=*/0, 9602 Best->FoundDecl, Method); 9603 if (BaseResult.isInvalid()) 9604 return ExprError(); 9605 Base = BaseResult.take(); 9606 9607 // Build the operator call. 9608 ExprResult FnExpr = CreateFunctionRefExpr(*this, Method); 9609 if (FnExpr.isInvalid()) 9610 return ExprError(); 9611 9612 QualType ResultTy = Method->getResultType(); 9613 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9614 ResultTy = ResultTy.getNonLValueExprType(Context); 9615 CXXOperatorCallExpr *TheCall = 9616 new (Context) CXXOperatorCallExpr(Context, OO_Arrow, FnExpr.take(), 9617 &Base, 1, ResultTy, VK, OpLoc); 9618 9619 if (CheckCallReturnType(Method->getResultType(), OpLoc, TheCall, 9620 Method)) 9621 return ExprError(); 9622 9623 return MaybeBindToTemporary(TheCall); 9624} 9625 9626/// FixOverloadedFunctionReference - E is an expression that refers to 9627/// a C++ overloaded function (possibly with some parentheses and 9628/// perhaps a '&' around it). We have resolved the overloaded function 9629/// to the function declaration Fn, so patch up the expression E to 9630/// refer (possibly indirectly) to Fn. Returns the new expr. 9631Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found, 9632 FunctionDecl *Fn) { 9633 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 9634 Expr *SubExpr = FixOverloadedFunctionReference(PE->getSubExpr(), 9635 Found, Fn); 9636 if (SubExpr == PE->getSubExpr()) 9637 return PE; 9638 9639 return new (Context) ParenExpr(PE->getLParen(), PE->getRParen(), SubExpr); 9640 } 9641 9642 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 9643 Expr *SubExpr = FixOverloadedFunctionReference(ICE->getSubExpr(), 9644 Found, Fn); 9645 assert(Context.hasSameType(ICE->getSubExpr()->getType(), 9646 SubExpr->getType()) && 9647 "Implicit cast type cannot be determined from overload"); 9648 assert(ICE->path_empty() && "fixing up hierarchy conversion?"); 9649 if (SubExpr == ICE->getSubExpr()) 9650 return ICE; 9651 9652 return ImplicitCastExpr::Create(Context, ICE->getType(), 9653 ICE->getCastKind(), 9654 SubExpr, 0, 9655 ICE->getValueKind()); 9656 } 9657 9658 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(E)) { 9659 assert(UnOp->getOpcode() == UO_AddrOf && 9660 "Can only take the address of an overloaded function"); 9661 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 9662 if (Method->isStatic()) { 9663 // Do nothing: static member functions aren't any different 9664 // from non-member functions. 9665 } else { 9666 // Fix the sub expression, which really has to be an 9667 // UnresolvedLookupExpr holding an overloaded member function 9668 // or template. 9669 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 9670 Found, Fn); 9671 if (SubExpr == UnOp->getSubExpr()) 9672 return UnOp; 9673 9674 assert(isa<DeclRefExpr>(SubExpr) 9675 && "fixed to something other than a decl ref"); 9676 assert(cast<DeclRefExpr>(SubExpr)->getQualifier() 9677 && "fixed to a member ref with no nested name qualifier"); 9678 9679 // We have taken the address of a pointer to member 9680 // function. Perform the computation here so that we get the 9681 // appropriate pointer to member type. 9682 QualType ClassType 9683 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 9684 QualType MemPtrType 9685 = Context.getMemberPointerType(Fn->getType(), ClassType.getTypePtr()); 9686 9687 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, MemPtrType, 9688 VK_RValue, OK_Ordinary, 9689 UnOp->getOperatorLoc()); 9690 } 9691 } 9692 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 9693 Found, Fn); 9694 if (SubExpr == UnOp->getSubExpr()) 9695 return UnOp; 9696 9697 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, 9698 Context.getPointerType(SubExpr->getType()), 9699 VK_RValue, OK_Ordinary, 9700 UnOp->getOperatorLoc()); 9701 } 9702 9703 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { 9704 // FIXME: avoid copy. 9705 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9706 if (ULE->hasExplicitTemplateArgs()) { 9707 ULE->copyTemplateArgumentsInto(TemplateArgsBuffer); 9708 TemplateArgs = &TemplateArgsBuffer; 9709 } 9710 9711 return DeclRefExpr::Create(Context, 9712 ULE->getQualifierLoc(), 9713 Fn, 9714 ULE->getNameLoc(), 9715 Fn->getType(), 9716 VK_LValue, 9717 Found.getDecl(), 9718 TemplateArgs); 9719 } 9720 9721 if (UnresolvedMemberExpr *MemExpr = dyn_cast<UnresolvedMemberExpr>(E)) { 9722 // FIXME: avoid copy. 9723 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9724 if (MemExpr->hasExplicitTemplateArgs()) { 9725 MemExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 9726 TemplateArgs = &TemplateArgsBuffer; 9727 } 9728 9729 Expr *Base; 9730 9731 // If we're filling in a static method where we used to have an 9732 // implicit member access, rewrite to a simple decl ref. 9733 if (MemExpr->isImplicitAccess()) { 9734 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 9735 return DeclRefExpr::Create(Context, 9736 MemExpr->getQualifierLoc(), 9737 Fn, 9738 MemExpr->getMemberLoc(), 9739 Fn->getType(), 9740 VK_LValue, 9741 Found.getDecl(), 9742 TemplateArgs); 9743 } else { 9744 SourceLocation Loc = MemExpr->getMemberLoc(); 9745 if (MemExpr->getQualifier()) 9746 Loc = MemExpr->getQualifierLoc().getBeginLoc(); 9747 Base = new (Context) CXXThisExpr(Loc, 9748 MemExpr->getBaseType(), 9749 /*isImplicit=*/true); 9750 } 9751 } else 9752 Base = MemExpr->getBase(); 9753 9754 ExprValueKind valueKind; 9755 QualType type; 9756 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 9757 valueKind = VK_LValue; 9758 type = Fn->getType(); 9759 } else { 9760 valueKind = VK_RValue; 9761 type = Context.BoundMemberTy; 9762 } 9763 9764 return MemberExpr::Create(Context, Base, 9765 MemExpr->isArrow(), 9766 MemExpr->getQualifierLoc(), 9767 Fn, 9768 Found, 9769 MemExpr->getMemberNameInfo(), 9770 TemplateArgs, 9771 type, valueKind, OK_Ordinary); 9772 } 9773 9774 llvm_unreachable("Invalid reference to overloaded function"); 9775 return E; 9776} 9777 9778ExprResult Sema::FixOverloadedFunctionReference(ExprResult E, 9779 DeclAccessPair Found, 9780 FunctionDecl *Fn) { 9781 return Owned(FixOverloadedFunctionReference((Expr *)E.get(), Found, Fn)); 9782} 9783 9784} // end namespace clang 9785