1 //===--- SemaOverload.cpp - C++ Overloading -------------------------------===// 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/Overload.h" 15 #include "clang/AST/ASTContext.h" 16 #include "clang/AST/CXXInheritance.h" 17 #include "clang/AST/DeclObjC.h" 18 #include "clang/AST/Expr.h" 19 #include "clang/AST/ExprCXX.h" 20 #include "clang/AST/ExprObjC.h" 21 #include "clang/AST/TypeOrdering.h" 22 #include "clang/Basic/Diagnostic.h" 23 #include "clang/Basic/PartialDiagnostic.h" 24 #include "clang/Lex/Preprocessor.h" 25 #include "clang/Sema/Initialization.h" 26 #include "clang/Sema/Lookup.h" 27 #include "clang/Sema/SemaInternal.h" 28 #include "clang/Sema/Template.h" 29 #include "clang/Sema/TemplateDeduction.h" 30 #include "llvm/ADT/DenseSet.h" 31 #include "llvm/ADT/STLExtras.h" 32 #include "llvm/ADT/SmallPtrSet.h" 33 #include "llvm/ADT/SmallString.h" 34 #include <algorithm> 35 36 namespace clang { 37 using namespace sema; 38 39 /// A convenience routine for creating a decayed reference to a function. 40 static ExprResult 41 CreateFunctionRefExpr(Sema &S, FunctionDecl *Fn, NamedDecl *FoundDecl, 42 bool HadMultipleCandidates, 43 SourceLocation Loc = SourceLocation(), 44 const DeclarationNameLoc &LocInfo = DeclarationNameLoc()){ 45 DeclRefExpr *DRE = new (S.Context) DeclRefExpr(Fn, false, Fn->getType(), 46 VK_LValue, Loc, LocInfo); 47 if (HadMultipleCandidates) 48 DRE->setHadMultipleCandidates(true); 49 50 S.MarkDeclRefReferenced(DRE); 51 S.DiagnoseUseOfDecl(FoundDecl, Loc); 52 53 ExprResult E = S.Owned(DRE); 54 E = S.DefaultFunctionArrayConversion(E.take()); 55 if (E.isInvalid()) 56 return ExprError(); 57 return E; 58 } 59 60 static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType, 61 bool InOverloadResolution, 62 StandardConversionSequence &SCS, 63 bool CStyle, 64 bool AllowObjCWritebackConversion); 65 66 static bool IsTransparentUnionStandardConversion(Sema &S, Expr* From, 67 QualType &ToType, 68 bool InOverloadResolution, 69 StandardConversionSequence &SCS, 70 bool CStyle); 71 static OverloadingResult 72 IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 73 UserDefinedConversionSequence& User, 74 OverloadCandidateSet& Conversions, 75 bool AllowExplicit); 76 77 78 static ImplicitConversionSequence::CompareKind 79 CompareStandardConversionSequences(Sema &S, 80 const StandardConversionSequence& SCS1, 81 const StandardConversionSequence& SCS2); 82 83 static ImplicitConversionSequence::CompareKind 84 CompareQualificationConversions(Sema &S, 85 const StandardConversionSequence& SCS1, 86 const StandardConversionSequence& SCS2); 87 88 static ImplicitConversionSequence::CompareKind 89 CompareDerivedToBaseConversions(Sema &S, 90 const StandardConversionSequence& SCS1, 91 const StandardConversionSequence& SCS2); 92 93 94 95 /// GetConversionCategory - Retrieve the implicit conversion 96 /// category corresponding to the given implicit conversion kind. 97 ImplicitConversionCategory 98 GetConversionCategory(ImplicitConversionKind Kind) { 99 static const ImplicitConversionCategory 100 Category[(int)ICK_Num_Conversion_Kinds] = { 101 ICC_Identity, 102 ICC_Lvalue_Transformation, 103 ICC_Lvalue_Transformation, 104 ICC_Lvalue_Transformation, 105 ICC_Identity, 106 ICC_Qualification_Adjustment, 107 ICC_Promotion, 108 ICC_Promotion, 109 ICC_Promotion, 110 ICC_Conversion, 111 ICC_Conversion, 112 ICC_Conversion, 113 ICC_Conversion, 114 ICC_Conversion, 115 ICC_Conversion, 116 ICC_Conversion, 117 ICC_Conversion, 118 ICC_Conversion, 119 ICC_Conversion, 120 ICC_Conversion, 121 ICC_Conversion, 122 ICC_Conversion 123 }; 124 return Category[(int)Kind]; 125 } 126 127 /// GetConversionRank - Retrieve the implicit conversion rank 128 /// corresponding to the given implicit conversion kind. 129 ImplicitConversionRank GetConversionRank(ImplicitConversionKind Kind) { 130 static const ImplicitConversionRank 131 Rank[(int)ICK_Num_Conversion_Kinds] = { 132 ICR_Exact_Match, 133 ICR_Exact_Match, 134 ICR_Exact_Match, 135 ICR_Exact_Match, 136 ICR_Exact_Match, 137 ICR_Exact_Match, 138 ICR_Promotion, 139 ICR_Promotion, 140 ICR_Promotion, 141 ICR_Conversion, 142 ICR_Conversion, 143 ICR_Conversion, 144 ICR_Conversion, 145 ICR_Conversion, 146 ICR_Conversion, 147 ICR_Conversion, 148 ICR_Conversion, 149 ICR_Conversion, 150 ICR_Conversion, 151 ICR_Conversion, 152 ICR_Complex_Real_Conversion, 153 ICR_Conversion, 154 ICR_Conversion, 155 ICR_Writeback_Conversion 156 }; 157 return Rank[(int)Kind]; 158 } 159 160 /// GetImplicitConversionName - Return the name of this kind of 161 /// implicit conversion. 162 const char* GetImplicitConversionName(ImplicitConversionKind Kind) { 163 static const char* const Name[(int)ICK_Num_Conversion_Kinds] = { 164 "No conversion", 165 "Lvalue-to-rvalue", 166 "Array-to-pointer", 167 "Function-to-pointer", 168 "Noreturn adjustment", 169 "Qualification", 170 "Integral promotion", 171 "Floating point promotion", 172 "Complex promotion", 173 "Integral conversion", 174 "Floating conversion", 175 "Complex conversion", 176 "Floating-integral conversion", 177 "Pointer conversion", 178 "Pointer-to-member conversion", 179 "Boolean conversion", 180 "Compatible-types conversion", 181 "Derived-to-base conversion", 182 "Vector conversion", 183 "Vector splat", 184 "Complex-real conversion", 185 "Block Pointer conversion", 186 "Transparent Union Conversion" 187 "Writeback conversion" 188 }; 189 return Name[Kind]; 190 } 191 192 /// StandardConversionSequence - Set the standard conversion 193 /// sequence to the identity conversion. 194 void StandardConversionSequence::setAsIdentityConversion() { 195 First = ICK_Identity; 196 Second = ICK_Identity; 197 Third = ICK_Identity; 198 DeprecatedStringLiteralToCharPtr = false; 199 QualificationIncludesObjCLifetime = false; 200 ReferenceBinding = false; 201 DirectBinding = false; 202 IsLvalueReference = true; 203 BindsToFunctionLvalue = false; 204 BindsToRvalue = false; 205 BindsImplicitObjectArgumentWithoutRefQualifier = false; 206 ObjCLifetimeConversionBinding = false; 207 CopyConstructor = 0; 208 } 209 210 /// getRank - Retrieve the rank of this standard conversion sequence 211 /// (C++ 13.3.3.1.1p3). The rank is the largest rank of each of the 212 /// implicit conversions. 213 ImplicitConversionRank StandardConversionSequence::getRank() const { 214 ImplicitConversionRank Rank = ICR_Exact_Match; 215 if (GetConversionRank(First) > Rank) 216 Rank = GetConversionRank(First); 217 if (GetConversionRank(Second) > Rank) 218 Rank = GetConversionRank(Second); 219 if (GetConversionRank(Third) > Rank) 220 Rank = GetConversionRank(Third); 221 return Rank; 222 } 223 224 /// isPointerConversionToBool - Determines whether this conversion is 225 /// a conversion of a pointer or pointer-to-member to bool. This is 226 /// used as part of the ranking of standard conversion sequences 227 /// (C++ 13.3.3.2p4). 228 bool StandardConversionSequence::isPointerConversionToBool() const { 229 // Note that FromType has not necessarily been transformed by the 230 // array-to-pointer or function-to-pointer implicit conversions, so 231 // check for their presence as well as checking whether FromType is 232 // a pointer. 233 if (getToType(1)->isBooleanType() && 234 (getFromType()->isPointerType() || 235 getFromType()->isObjCObjectPointerType() || 236 getFromType()->isBlockPointerType() || 237 getFromType()->isNullPtrType() || 238 First == ICK_Array_To_Pointer || First == ICK_Function_To_Pointer)) 239 return true; 240 241 return false; 242 } 243 244 /// isPointerConversionToVoidPointer - Determines whether this 245 /// conversion is a conversion of a pointer to a void pointer. This is 246 /// used as part of the ranking of standard conversion sequences (C++ 247 /// 13.3.3.2p4). 248 bool 249 StandardConversionSequence:: 250 isPointerConversionToVoidPointer(ASTContext& Context) const { 251 QualType FromType = getFromType(); 252 QualType ToType = getToType(1); 253 254 // Note that FromType has not necessarily been transformed by the 255 // array-to-pointer implicit conversion, so check for its presence 256 // and redo the conversion to get a pointer. 257 if (First == ICK_Array_To_Pointer) 258 FromType = Context.getArrayDecayedType(FromType); 259 260 if (Second == ICK_Pointer_Conversion && FromType->isAnyPointerType()) 261 if (const PointerType* ToPtrType = ToType->getAs<PointerType>()) 262 return ToPtrType->getPointeeType()->isVoidType(); 263 264 return false; 265 } 266 267 /// Skip any implicit casts which could be either part of a narrowing conversion 268 /// or after one in an implicit conversion. 269 static const Expr *IgnoreNarrowingConversion(const Expr *Converted) { 270 while (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(Converted)) { 271 switch (ICE->getCastKind()) { 272 case CK_NoOp: 273 case CK_IntegralCast: 274 case CK_IntegralToBoolean: 275 case CK_IntegralToFloating: 276 case CK_FloatingToIntegral: 277 case CK_FloatingToBoolean: 278 case CK_FloatingCast: 279 Converted = ICE->getSubExpr(); 280 continue; 281 282 default: 283 return Converted; 284 } 285 } 286 287 return Converted; 288 } 289 290 /// Check if this standard conversion sequence represents a narrowing 291 /// conversion, according to C++11 [dcl.init.list]p7. 292 /// 293 /// \param Ctx The AST context. 294 /// \param Converted The result of applying this standard conversion sequence. 295 /// \param ConstantValue If this is an NK_Constant_Narrowing conversion, the 296 /// value of the expression prior to the narrowing conversion. 297 /// \param ConstantType If this is an NK_Constant_Narrowing conversion, the 298 /// type of the expression prior to the narrowing conversion. 299 NarrowingKind 300 StandardConversionSequence::getNarrowingKind(ASTContext &Ctx, 301 const Expr *Converted, 302 APValue &ConstantValue, 303 QualType &ConstantType) const { 304 assert(Ctx.getLangOpts().CPlusPlus && "narrowing check outside C++"); 305 306 // C++11 [dcl.init.list]p7: 307 // A narrowing conversion is an implicit conversion ... 308 QualType FromType = getToType(0); 309 QualType ToType = getToType(1); 310 switch (Second) { 311 // -- from a floating-point type to an integer type, or 312 // 313 // -- from an integer type or unscoped enumeration type to a floating-point 314 // type, except where the source is a constant expression and the actual 315 // value after conversion will fit into the target type and will produce 316 // the original value when converted back to the original type, or 317 case ICK_Floating_Integral: 318 if (FromType->isRealFloatingType() && ToType->isIntegralType(Ctx)) { 319 return NK_Type_Narrowing; 320 } else if (FromType->isIntegralType(Ctx) && ToType->isRealFloatingType()) { 321 llvm::APSInt IntConstantValue; 322 const Expr *Initializer = IgnoreNarrowingConversion(Converted); 323 if (Initializer && 324 Initializer->isIntegerConstantExpr(IntConstantValue, Ctx)) { 325 // Convert the integer to the floating type. 326 llvm::APFloat Result(Ctx.getFloatTypeSemantics(ToType)); 327 Result.convertFromAPInt(IntConstantValue, IntConstantValue.isSigned(), 328 llvm::APFloat::rmNearestTiesToEven); 329 // And back. 330 llvm::APSInt ConvertedValue = IntConstantValue; 331 bool ignored; 332 Result.convertToInteger(ConvertedValue, 333 llvm::APFloat::rmTowardZero, &ignored); 334 // If the resulting value is different, this was a narrowing conversion. 335 if (IntConstantValue != ConvertedValue) { 336 ConstantValue = APValue(IntConstantValue); 337 ConstantType = Initializer->getType(); 338 return NK_Constant_Narrowing; 339 } 340 } else { 341 // Variables are always narrowings. 342 return NK_Variable_Narrowing; 343 } 344 } 345 return NK_Not_Narrowing; 346 347 // -- from long double to double or float, or from double to float, except 348 // where the source is a constant expression and the actual value after 349 // conversion is within the range of values that can be represented (even 350 // if it cannot be represented exactly), or 351 case ICK_Floating_Conversion: 352 if (FromType->isRealFloatingType() && ToType->isRealFloatingType() && 353 Ctx.getFloatingTypeOrder(FromType, ToType) == 1) { 354 // FromType is larger than ToType. 355 const Expr *Initializer = IgnoreNarrowingConversion(Converted); 356 if (Initializer->isCXX11ConstantExpr(Ctx, &ConstantValue)) { 357 // Constant! 358 assert(ConstantValue.isFloat()); 359 llvm::APFloat FloatVal = ConstantValue.getFloat(); 360 // Convert the source value into the target type. 361 bool ignored; 362 llvm::APFloat::opStatus ConvertStatus = FloatVal.convert( 363 Ctx.getFloatTypeSemantics(ToType), 364 llvm::APFloat::rmNearestTiesToEven, &ignored); 365 // If there was no overflow, the source value is within the range of 366 // values that can be represented. 367 if (ConvertStatus & llvm::APFloat::opOverflow) { 368 ConstantType = Initializer->getType(); 369 return NK_Constant_Narrowing; 370 } 371 } else { 372 return NK_Variable_Narrowing; 373 } 374 } 375 return NK_Not_Narrowing; 376 377 // -- from an integer type or unscoped enumeration type to an integer type 378 // that cannot represent all the values of the original type, except where 379 // the source is a constant expression and the actual value after 380 // conversion will fit into the target type and will produce the original 381 // value when converted back to the original type. 382 case ICK_Boolean_Conversion: // Bools are integers too. 383 if (!FromType->isIntegralOrUnscopedEnumerationType()) { 384 // Boolean conversions can be from pointers and pointers to members 385 // [conv.bool], and those aren't considered narrowing conversions. 386 return NK_Not_Narrowing; 387 } // Otherwise, fall through to the integral case. 388 case ICK_Integral_Conversion: { 389 assert(FromType->isIntegralOrUnscopedEnumerationType()); 390 assert(ToType->isIntegralOrUnscopedEnumerationType()); 391 const bool FromSigned = FromType->isSignedIntegerOrEnumerationType(); 392 const unsigned FromWidth = Ctx.getIntWidth(FromType); 393 const bool ToSigned = ToType->isSignedIntegerOrEnumerationType(); 394 const unsigned ToWidth = Ctx.getIntWidth(ToType); 395 396 if (FromWidth > ToWidth || 397 (FromWidth == ToWidth && FromSigned != ToSigned) || 398 (FromSigned && !ToSigned)) { 399 // Not all values of FromType can be represented in ToType. 400 llvm::APSInt InitializerValue; 401 const Expr *Initializer = IgnoreNarrowingConversion(Converted); 402 if (!Initializer->isIntegerConstantExpr(InitializerValue, Ctx)) { 403 // Such conversions on variables are always narrowing. 404 return NK_Variable_Narrowing; 405 } 406 bool Narrowing = false; 407 if (FromWidth < ToWidth) { 408 // Negative -> unsigned is narrowing. Otherwise, more bits is never 409 // narrowing. 410 if (InitializerValue.isSigned() && InitializerValue.isNegative()) 411 Narrowing = true; 412 } else { 413 // Add a bit to the InitializerValue so we don't have to worry about 414 // signed vs. unsigned comparisons. 415 InitializerValue = InitializerValue.extend( 416 InitializerValue.getBitWidth() + 1); 417 // Convert the initializer to and from the target width and signed-ness. 418 llvm::APSInt ConvertedValue = InitializerValue; 419 ConvertedValue = ConvertedValue.trunc(ToWidth); 420 ConvertedValue.setIsSigned(ToSigned); 421 ConvertedValue = ConvertedValue.extend(InitializerValue.getBitWidth()); 422 ConvertedValue.setIsSigned(InitializerValue.isSigned()); 423 // If the result is different, this was a narrowing conversion. 424 if (ConvertedValue != InitializerValue) 425 Narrowing = true; 426 } 427 if (Narrowing) { 428 ConstantType = Initializer->getType(); 429 ConstantValue = APValue(InitializerValue); 430 return NK_Constant_Narrowing; 431 } 432 } 433 return NK_Not_Narrowing; 434 } 435 436 default: 437 // Other kinds of conversions are not narrowings. 438 return NK_Not_Narrowing; 439 } 440 } 441 442 /// DebugPrint - Print this standard conversion sequence to standard 443 /// error. Useful for debugging overloading issues. 444 void StandardConversionSequence::DebugPrint() const { 445 raw_ostream &OS = llvm::errs(); 446 bool PrintedSomething = false; 447 if (First != ICK_Identity) { 448 OS << GetImplicitConversionName(First); 449 PrintedSomething = true; 450 } 451 452 if (Second != ICK_Identity) { 453 if (PrintedSomething) { 454 OS << " -> "; 455 } 456 OS << GetImplicitConversionName(Second); 457 458 if (CopyConstructor) { 459 OS << " (by copy constructor)"; 460 } else if (DirectBinding) { 461 OS << " (direct reference binding)"; 462 } else if (ReferenceBinding) { 463 OS << " (reference binding)"; 464 } 465 PrintedSomething = true; 466 } 467 468 if (Third != ICK_Identity) { 469 if (PrintedSomething) { 470 OS << " -> "; 471 } 472 OS << GetImplicitConversionName(Third); 473 PrintedSomething = true; 474 } 475 476 if (!PrintedSomething) { 477 OS << "No conversions required"; 478 } 479 } 480 481 /// DebugPrint - Print this user-defined conversion sequence to standard 482 /// error. Useful for debugging overloading issues. 483 void UserDefinedConversionSequence::DebugPrint() const { 484 raw_ostream &OS = llvm::errs(); 485 if (Before.First || Before.Second || Before.Third) { 486 Before.DebugPrint(); 487 OS << " -> "; 488 } 489 if (ConversionFunction) 490 OS << '\'' << *ConversionFunction << '\''; 491 else 492 OS << "aggregate initialization"; 493 if (After.First || After.Second || After.Third) { 494 OS << " -> "; 495 After.DebugPrint(); 496 } 497 } 498 499 /// DebugPrint - Print this implicit conversion sequence to standard 500 /// error. Useful for debugging overloading issues. 501 void ImplicitConversionSequence::DebugPrint() const { 502 raw_ostream &OS = llvm::errs(); 503 switch (ConversionKind) { 504 case StandardConversion: 505 OS << "Standard conversion: "; 506 Standard.DebugPrint(); 507 break; 508 case UserDefinedConversion: 509 OS << "User-defined conversion: "; 510 UserDefined.DebugPrint(); 511 break; 512 case EllipsisConversion: 513 OS << "Ellipsis conversion"; 514 break; 515 case AmbiguousConversion: 516 OS << "Ambiguous conversion"; 517 break; 518 case BadConversion: 519 OS << "Bad conversion"; 520 break; 521 } 522 523 OS << "\n"; 524 } 525 526 void AmbiguousConversionSequence::construct() { 527 new (&conversions()) ConversionSet(); 528 } 529 530 void AmbiguousConversionSequence::destruct() { 531 conversions().~ConversionSet(); 532 } 533 534 void 535 AmbiguousConversionSequence::copyFrom(const AmbiguousConversionSequence &O) { 536 FromTypePtr = O.FromTypePtr; 537 ToTypePtr = O.ToTypePtr; 538 new (&conversions()) ConversionSet(O.conversions()); 539 } 540 541 namespace { 542 // Structure used by OverloadCandidate::DeductionFailureInfo to store 543 // template argument information. 544 struct DFIArguments { 545 TemplateArgument FirstArg; 546 TemplateArgument SecondArg; 547 }; 548 // Structure used by OverloadCandidate::DeductionFailureInfo to store 549 // template parameter and template argument information. 550 struct DFIParamWithArguments : DFIArguments { 551 TemplateParameter Param; 552 }; 553 } 554 555 /// \brief Convert from Sema's representation of template deduction information 556 /// to the form used in overload-candidate information. 557 OverloadCandidate::DeductionFailureInfo 558 static MakeDeductionFailureInfo(ASTContext &Context, 559 Sema::TemplateDeductionResult TDK, 560 TemplateDeductionInfo &Info) { 561 OverloadCandidate::DeductionFailureInfo Result; 562 Result.Result = static_cast<unsigned>(TDK); 563 Result.HasDiagnostic = false; 564 Result.Data = 0; 565 switch (TDK) { 566 case Sema::TDK_Success: 567 case Sema::TDK_Invalid: 568 case Sema::TDK_InstantiationDepth: 569 case Sema::TDK_TooManyArguments: 570 case Sema::TDK_TooFewArguments: 571 break; 572 573 case Sema::TDK_Incomplete: 574 case Sema::TDK_InvalidExplicitArguments: 575 Result.Data = Info.Param.getOpaqueValue(); 576 break; 577 578 case Sema::TDK_NonDeducedMismatch: { 579 // FIXME: Should allocate from normal heap so that we can free this later. 580 DFIArguments *Saved = new (Context) DFIArguments; 581 Saved->FirstArg = Info.FirstArg; 582 Saved->SecondArg = Info.SecondArg; 583 Result.Data = Saved; 584 break; 585 } 586 587 case Sema::TDK_Inconsistent: 588 case Sema::TDK_Underqualified: { 589 // FIXME: Should allocate from normal heap so that we can free this later. 590 DFIParamWithArguments *Saved = new (Context) DFIParamWithArguments; 591 Saved->Param = Info.Param; 592 Saved->FirstArg = Info.FirstArg; 593 Saved->SecondArg = Info.SecondArg; 594 Result.Data = Saved; 595 break; 596 } 597 598 case Sema::TDK_SubstitutionFailure: 599 Result.Data = Info.take(); 600 if (Info.hasSFINAEDiagnostic()) { 601 PartialDiagnosticAt *Diag = new (Result.Diagnostic) PartialDiagnosticAt( 602 SourceLocation(), PartialDiagnostic::NullDiagnostic()); 603 Info.takeSFINAEDiagnostic(*Diag); 604 Result.HasDiagnostic = true; 605 } 606 break; 607 608 case Sema::TDK_FailedOverloadResolution: 609 Result.Data = Info.Expression; 610 break; 611 612 case Sema::TDK_MiscellaneousDeductionFailure: 613 break; 614 } 615 616 return Result; 617 } 618 619 void OverloadCandidate::DeductionFailureInfo::Destroy() { 620 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 621 case Sema::TDK_Success: 622 case Sema::TDK_Invalid: 623 case Sema::TDK_InstantiationDepth: 624 case Sema::TDK_Incomplete: 625 case Sema::TDK_TooManyArguments: 626 case Sema::TDK_TooFewArguments: 627 case Sema::TDK_InvalidExplicitArguments: 628 case Sema::TDK_FailedOverloadResolution: 629 break; 630 631 case Sema::TDK_Inconsistent: 632 case Sema::TDK_Underqualified: 633 case Sema::TDK_NonDeducedMismatch: 634 // FIXME: Destroy the data? 635 Data = 0; 636 break; 637 638 case Sema::TDK_SubstitutionFailure: 639 // FIXME: Destroy the template argument list? 640 Data = 0; 641 if (PartialDiagnosticAt *Diag = getSFINAEDiagnostic()) { 642 Diag->~PartialDiagnosticAt(); 643 HasDiagnostic = false; 644 } 645 break; 646 647 // Unhandled 648 case Sema::TDK_MiscellaneousDeductionFailure: 649 break; 650 } 651 } 652 653 PartialDiagnosticAt * 654 OverloadCandidate::DeductionFailureInfo::getSFINAEDiagnostic() { 655 if (HasDiagnostic) 656 return static_cast<PartialDiagnosticAt*>(static_cast<void*>(Diagnostic)); 657 return 0; 658 } 659 660 TemplateParameter 661 OverloadCandidate::DeductionFailureInfo::getTemplateParameter() { 662 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 663 case Sema::TDK_Success: 664 case Sema::TDK_Invalid: 665 case Sema::TDK_InstantiationDepth: 666 case Sema::TDK_TooManyArguments: 667 case Sema::TDK_TooFewArguments: 668 case Sema::TDK_SubstitutionFailure: 669 case Sema::TDK_NonDeducedMismatch: 670 case Sema::TDK_FailedOverloadResolution: 671 return TemplateParameter(); 672 673 case Sema::TDK_Incomplete: 674 case Sema::TDK_InvalidExplicitArguments: 675 return TemplateParameter::getFromOpaqueValue(Data); 676 677 case Sema::TDK_Inconsistent: 678 case Sema::TDK_Underqualified: 679 return static_cast<DFIParamWithArguments*>(Data)->Param; 680 681 // Unhandled 682 case Sema::TDK_MiscellaneousDeductionFailure: 683 break; 684 } 685 686 return TemplateParameter(); 687 } 688 689 TemplateArgumentList * 690 OverloadCandidate::DeductionFailureInfo::getTemplateArgumentList() { 691 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 692 case Sema::TDK_Success: 693 case Sema::TDK_Invalid: 694 case Sema::TDK_InstantiationDepth: 695 case Sema::TDK_TooManyArguments: 696 case Sema::TDK_TooFewArguments: 697 case Sema::TDK_Incomplete: 698 case Sema::TDK_InvalidExplicitArguments: 699 case Sema::TDK_Inconsistent: 700 case Sema::TDK_Underqualified: 701 case Sema::TDK_NonDeducedMismatch: 702 case Sema::TDK_FailedOverloadResolution: 703 return 0; 704 705 case Sema::TDK_SubstitutionFailure: 706 return static_cast<TemplateArgumentList*>(Data); 707 708 // Unhandled 709 case Sema::TDK_MiscellaneousDeductionFailure: 710 break; 711 } 712 713 return 0; 714 } 715 716 const TemplateArgument *OverloadCandidate::DeductionFailureInfo::getFirstArg() { 717 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 718 case Sema::TDK_Success: 719 case Sema::TDK_Invalid: 720 case Sema::TDK_InstantiationDepth: 721 case Sema::TDK_Incomplete: 722 case Sema::TDK_TooManyArguments: 723 case Sema::TDK_TooFewArguments: 724 case Sema::TDK_InvalidExplicitArguments: 725 case Sema::TDK_SubstitutionFailure: 726 case Sema::TDK_FailedOverloadResolution: 727 return 0; 728 729 case Sema::TDK_Inconsistent: 730 case Sema::TDK_Underqualified: 731 case Sema::TDK_NonDeducedMismatch: 732 return &static_cast<DFIArguments*>(Data)->FirstArg; 733 734 // Unhandled 735 case Sema::TDK_MiscellaneousDeductionFailure: 736 break; 737 } 738 739 return 0; 740 } 741 742 const TemplateArgument * 743 OverloadCandidate::DeductionFailureInfo::getSecondArg() { 744 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 745 case Sema::TDK_Success: 746 case Sema::TDK_Invalid: 747 case Sema::TDK_InstantiationDepth: 748 case Sema::TDK_Incomplete: 749 case Sema::TDK_TooManyArguments: 750 case Sema::TDK_TooFewArguments: 751 case Sema::TDK_InvalidExplicitArguments: 752 case Sema::TDK_SubstitutionFailure: 753 case Sema::TDK_FailedOverloadResolution: 754 return 0; 755 756 case Sema::TDK_Inconsistent: 757 case Sema::TDK_Underqualified: 758 case Sema::TDK_NonDeducedMismatch: 759 return &static_cast<DFIArguments*>(Data)->SecondArg; 760 761 // Unhandled 762 case Sema::TDK_MiscellaneousDeductionFailure: 763 break; 764 } 765 766 return 0; 767 } 768 769 Expr * 770 OverloadCandidate::DeductionFailureInfo::getExpr() { 771 if (static_cast<Sema::TemplateDeductionResult>(Result) == 772 Sema::TDK_FailedOverloadResolution) 773 return static_cast<Expr*>(Data); 774 775 return 0; 776 } 777 778 void OverloadCandidateSet::destroyCandidates() { 779 for (iterator i = begin(), e = end(); i != e; ++i) { 780 for (unsigned ii = 0, ie = i->NumConversions; ii != ie; ++ii) 781 i->Conversions[ii].~ImplicitConversionSequence(); 782 if (!i->Viable && i->FailureKind == ovl_fail_bad_deduction) 783 i->DeductionFailure.Destroy(); 784 } 785 } 786 787 void OverloadCandidateSet::clear() { 788 destroyCandidates(); 789 NumInlineSequences = 0; 790 Candidates.clear(); 791 Functions.clear(); 792 } 793 794 namespace { 795 class UnbridgedCastsSet { 796 struct Entry { 797 Expr **Addr; 798 Expr *Saved; 799 }; 800 SmallVector<Entry, 2> Entries; 801 802 public: 803 void save(Sema &S, Expr *&E) { 804 assert(E->hasPlaceholderType(BuiltinType::ARCUnbridgedCast)); 805 Entry entry = { &E, E }; 806 Entries.push_back(entry); 807 E = S.stripARCUnbridgedCast(E); 808 } 809 810 void restore() { 811 for (SmallVectorImpl<Entry>::iterator 812 i = Entries.begin(), e = Entries.end(); i != e; ++i) 813 *i->Addr = i->Saved; 814 } 815 }; 816 } 817 818 /// checkPlaceholderForOverload - Do any interesting placeholder-like 819 /// preprocessing on the given expression. 820 /// 821 /// \param unbridgedCasts a collection to which to add unbridged casts; 822 /// without this, they will be immediately diagnosed as errors 823 /// 824 /// Return true on unrecoverable error. 825 static bool checkPlaceholderForOverload(Sema &S, Expr *&E, 826 UnbridgedCastsSet *unbridgedCasts = 0) { 827 if (const BuiltinType *placeholder = E->getType()->getAsPlaceholderType()) { 828 // We can't handle overloaded expressions here because overload 829 // resolution might reasonably tweak them. 830 if (placeholder->getKind() == BuiltinType::Overload) return false; 831 832 // If the context potentially accepts unbridged ARC casts, strip 833 // the unbridged cast and add it to the collection for later restoration. 834 if (placeholder->getKind() == BuiltinType::ARCUnbridgedCast && 835 unbridgedCasts) { 836 unbridgedCasts->save(S, E); 837 return false; 838 } 839 840 // Go ahead and check everything else. 841 ExprResult result = S.CheckPlaceholderExpr(E); 842 if (result.isInvalid()) 843 return true; 844 845 E = result.take(); 846 return false; 847 } 848 849 // Nothing to do. 850 return false; 851 } 852 853 /// checkArgPlaceholdersForOverload - Check a set of call operands for 854 /// placeholders. 855 static bool checkArgPlaceholdersForOverload(Sema &S, Expr **args, 856 unsigned numArgs, 857 UnbridgedCastsSet &unbridged) { 858 for (unsigned i = 0; i != numArgs; ++i) 859 if (checkPlaceholderForOverload(S, args[i], &unbridged)) 860 return true; 861 862 return false; 863 } 864 865 // IsOverload - Determine whether the given New declaration is an 866 // overload of the declarations in Old. This routine returns false if 867 // New and Old cannot be overloaded, e.g., if New has the same 868 // signature as some function in Old (C++ 1.3.10) or if the Old 869 // declarations aren't functions (or function templates) at all. When 870 // it does return false, MatchedDecl will point to the decl that New 871 // cannot be overloaded with. This decl may be a UsingShadowDecl on 872 // top of the underlying declaration. 873 // 874 // Example: Given the following input: 875 // 876 // void f(int, float); // #1 877 // void f(int, int); // #2 878 // int f(int, int); // #3 879 // 880 // When we process #1, there is no previous declaration of "f", 881 // so IsOverload will not be used. 882 // 883 // When we process #2, Old contains only the FunctionDecl for #1. By 884 // comparing the parameter types, we see that #1 and #2 are overloaded 885 // (since they have different signatures), so this routine returns 886 // false; MatchedDecl is unchanged. 887 // 888 // When we process #3, Old is an overload set containing #1 and #2. We 889 // compare the signatures of #3 to #1 (they're overloaded, so we do 890 // nothing) and then #3 to #2. Since the signatures of #3 and #2 are 891 // identical (return types of functions are not part of the 892 // signature), IsOverload returns false and MatchedDecl will be set to 893 // point to the FunctionDecl for #2. 894 // 895 // 'NewIsUsingShadowDecl' indicates that 'New' is being introduced 896 // into a class by a using declaration. The rules for whether to hide 897 // shadow declarations ignore some properties which otherwise figure 898 // into a function template's signature. 899 Sema::OverloadKind 900 Sema::CheckOverload(Scope *S, FunctionDecl *New, const LookupResult &Old, 901 NamedDecl *&Match, bool NewIsUsingDecl) { 902 for (LookupResult::iterator I = Old.begin(), E = Old.end(); 903 I != E; ++I) { 904 NamedDecl *OldD = *I; 905 906 bool OldIsUsingDecl = false; 907 if (isa<UsingShadowDecl>(OldD)) { 908 OldIsUsingDecl = true; 909 910 // We can always introduce two using declarations into the same 911 // context, even if they have identical signatures. 912 if (NewIsUsingDecl) continue; 913 914 OldD = cast<UsingShadowDecl>(OldD)->getTargetDecl(); 915 } 916 917 // If either declaration was introduced by a using declaration, 918 // we'll need to use slightly different rules for matching. 919 // Essentially, these rules are the normal rules, except that 920 // function templates hide function templates with different 921 // return types or template parameter lists. 922 bool UseMemberUsingDeclRules = 923 (OldIsUsingDecl || NewIsUsingDecl) && CurContext->isRecord(); 924 925 if (FunctionTemplateDecl *OldT = dyn_cast<FunctionTemplateDecl>(OldD)) { 926 if (!IsOverload(New, OldT->getTemplatedDecl(), UseMemberUsingDeclRules)) { 927 if (UseMemberUsingDeclRules && OldIsUsingDecl) { 928 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I)); 929 continue; 930 } 931 932 Match = *I; 933 return Ovl_Match; 934 } 935 } else if (FunctionDecl *OldF = dyn_cast<FunctionDecl>(OldD)) { 936 if (!IsOverload(New, OldF, UseMemberUsingDeclRules)) { 937 if (UseMemberUsingDeclRules && OldIsUsingDecl) { 938 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I)); 939 continue; 940 } 941 942 Match = *I; 943 return Ovl_Match; 944 } 945 } else if (isa<UsingDecl>(OldD)) { 946 // We can overload with these, which can show up when doing 947 // redeclaration checks for UsingDecls. 948 assert(Old.getLookupKind() == LookupUsingDeclName); 949 } else if (isa<TagDecl>(OldD)) { 950 // We can always overload with tags by hiding them. 951 } else if (isa<UnresolvedUsingValueDecl>(OldD)) { 952 // Optimistically assume that an unresolved using decl will 953 // overload; if it doesn't, we'll have to diagnose during 954 // template instantiation. 955 } else { 956 // (C++ 13p1): 957 // Only function declarations can be overloaded; object and type 958 // declarations cannot be overloaded. 959 Match = *I; 960 return Ovl_NonFunction; 961 } 962 } 963 964 return Ovl_Overload; 965 } 966 967 static bool canBeOverloaded(const FunctionDecl &D) { 968 if (D.getAttr<OverloadableAttr>()) 969 return true; 970 if (D.isExternC()) 971 return false; 972 973 // Main cannot be overloaded (basic.start.main). 974 if (D.isMain()) 975 return false; 976 977 return true; 978 } 979 980 static bool shouldTryToOverload(Sema &S, FunctionDecl *New, FunctionDecl *Old, 981 bool UseUsingDeclRules) { 982 FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate(); 983 FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate(); 984 985 // C++ [temp.fct]p2: 986 // A function template can be overloaded with other function templates 987 // and with normal (non-template) functions. 988 if ((OldTemplate == 0) != (NewTemplate == 0)) 989 return true; 990 991 // Is the function New an overload of the function Old? 992 QualType OldQType = S.Context.getCanonicalType(Old->getType()); 993 QualType NewQType = S.Context.getCanonicalType(New->getType()); 994 995 // Compare the signatures (C++ 1.3.10) of the two functions to 996 // determine whether they are overloads. If we find any mismatch 997 // in the signature, they are overloads. 998 999 // If either of these functions is a K&R-style function (no 1000 // prototype), then we consider them to have matching signatures. 1001 if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) || 1002 isa<FunctionNoProtoType>(NewQType.getTypePtr())) 1003 return false; 1004 1005 const FunctionProtoType* OldType = cast<FunctionProtoType>(OldQType); 1006 const FunctionProtoType* NewType = cast<FunctionProtoType>(NewQType); 1007 1008 // The signature of a function includes the types of its 1009 // parameters (C++ 1.3.10), which includes the presence or absence 1010 // of the ellipsis; see C++ DR 357). 1011 if (OldQType != NewQType && 1012 (OldType->getNumArgs() != NewType->getNumArgs() || 1013 OldType->isVariadic() != NewType->isVariadic() || 1014 !S.FunctionArgTypesAreEqual(OldType, NewType))) 1015 return true; 1016 1017 // C++ [temp.over.link]p4: 1018 // The signature of a function template consists of its function 1019 // signature, its return type and its template parameter list. The names 1020 // of the template parameters are significant only for establishing the 1021 // relationship between the template parameters and the rest of the 1022 // signature. 1023 // 1024 // We check the return type and template parameter lists for function 1025 // templates first; the remaining checks follow. 1026 // 1027 // However, we don't consider either of these when deciding whether 1028 // a member introduced by a shadow declaration is hidden. 1029 if (!UseUsingDeclRules && NewTemplate && 1030 (!S.TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(), 1031 OldTemplate->getTemplateParameters(), 1032 false, S.TPL_TemplateMatch) || 1033 OldType->getResultType() != NewType->getResultType())) 1034 return true; 1035 1036 // If the function is a class member, its signature includes the 1037 // cv-qualifiers (if any) and ref-qualifier (if any) on the function itself. 1038 // 1039 // As part of this, also check whether one of the member functions 1040 // is static, in which case they are not overloads (C++ 1041 // 13.1p2). While not part of the definition of the signature, 1042 // this check is important to determine whether these functions 1043 // can be overloaded. 1044 CXXMethodDecl *OldMethod = dyn_cast<CXXMethodDecl>(Old); 1045 CXXMethodDecl *NewMethod = dyn_cast<CXXMethodDecl>(New); 1046 if (OldMethod && NewMethod && 1047 !OldMethod->isStatic() && !NewMethod->isStatic()) { 1048 if (OldMethod->getRefQualifier() != NewMethod->getRefQualifier()) { 1049 if (!UseUsingDeclRules && 1050 (OldMethod->getRefQualifier() == RQ_None || 1051 NewMethod->getRefQualifier() == RQ_None)) { 1052 // C++0x [over.load]p2: 1053 // - Member function declarations with the same name and the same 1054 // parameter-type-list as well as member function template 1055 // declarations with the same name, the same parameter-type-list, and 1056 // the same template parameter lists cannot be overloaded if any of 1057 // them, but not all, have a ref-qualifier (8.3.5). 1058 S.Diag(NewMethod->getLocation(), diag::err_ref_qualifier_overload) 1059 << NewMethod->getRefQualifier() << OldMethod->getRefQualifier(); 1060 S.Diag(OldMethod->getLocation(), diag::note_previous_declaration); 1061 } 1062 return true; 1063 } 1064 1065 // We may not have applied the implicit const for a constexpr member 1066 // function yet (because we haven't yet resolved whether this is a static 1067 // or non-static member function). Add it now, on the assumption that this 1068 // is a redeclaration of OldMethod. 1069 unsigned NewQuals = NewMethod->getTypeQualifiers(); 1070 if (NewMethod->isConstexpr() && !isa<CXXConstructorDecl>(NewMethod)) 1071 NewQuals |= Qualifiers::Const; 1072 if (OldMethod->getTypeQualifiers() != NewQuals) 1073 return true; 1074 } 1075 1076 // The signatures match; this is not an overload. 1077 return false; 1078 } 1079 1080 bool Sema::IsOverload(FunctionDecl *New, FunctionDecl *Old, 1081 bool UseUsingDeclRules) { 1082 if (!shouldTryToOverload(*this, New, Old, UseUsingDeclRules)) 1083 return false; 1084 1085 // If both of the functions are extern "C", then they are not 1086 // overloads. 1087 if (!canBeOverloaded(*Old) && !canBeOverloaded(*New)) 1088 return false; 1089 1090 return true; 1091 } 1092 1093 /// \brief Checks availability of the function depending on the current 1094 /// function context. Inside an unavailable function, unavailability is ignored. 1095 /// 1096 /// \returns true if \arg FD is unavailable and current context is inside 1097 /// an available function, false otherwise. 1098 bool Sema::isFunctionConsideredUnavailable(FunctionDecl *FD) { 1099 return FD->isUnavailable() && !cast<Decl>(CurContext)->isUnavailable(); 1100 } 1101 1102 /// \brief Tries a user-defined conversion from From to ToType. 1103 /// 1104 /// Produces an implicit conversion sequence for when a standard conversion 1105 /// is not an option. See TryImplicitConversion for more information. 1106 static ImplicitConversionSequence 1107 TryUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 1108 bool SuppressUserConversions, 1109 bool AllowExplicit, 1110 bool InOverloadResolution, 1111 bool CStyle, 1112 bool AllowObjCWritebackConversion) { 1113 ImplicitConversionSequence ICS; 1114 1115 if (SuppressUserConversions) { 1116 // We're not in the case above, so there is no conversion that 1117 // we can perform. 1118 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 1119 return ICS; 1120 } 1121 1122 // Attempt user-defined conversion. 1123 OverloadCandidateSet Conversions(From->getExprLoc()); 1124 OverloadingResult UserDefResult 1125 = IsUserDefinedConversion(S, From, ToType, ICS.UserDefined, Conversions, 1126 AllowExplicit); 1127 1128 if (UserDefResult == OR_Success) { 1129 ICS.setUserDefined(); 1130 // C++ [over.ics.user]p4: 1131 // A conversion of an expression of class type to the same class 1132 // type is given Exact Match rank, and a conversion of an 1133 // expression of class type to a base class of that type is 1134 // given Conversion rank, in spite of the fact that a copy 1135 // constructor (i.e., a user-defined conversion function) is 1136 // called for those cases. 1137 if (CXXConstructorDecl *Constructor 1138 = dyn_cast<CXXConstructorDecl>(ICS.UserDefined.ConversionFunction)) { 1139 QualType FromCanon 1140 = S.Context.getCanonicalType(From->getType().getUnqualifiedType()); 1141 QualType ToCanon 1142 = S.Context.getCanonicalType(ToType).getUnqualifiedType(); 1143 if (Constructor->isCopyConstructor() && 1144 (FromCanon == ToCanon || S.IsDerivedFrom(FromCanon, ToCanon))) { 1145 // Turn this into a "standard" conversion sequence, so that it 1146 // gets ranked with standard conversion sequences. 1147 ICS.setStandard(); 1148 ICS.Standard.setAsIdentityConversion(); 1149 ICS.Standard.setFromType(From->getType()); 1150 ICS.Standard.setAllToTypes(ToType); 1151 ICS.Standard.CopyConstructor = Constructor; 1152 if (ToCanon != FromCanon) 1153 ICS.Standard.Second = ICK_Derived_To_Base; 1154 } 1155 } 1156 1157 // C++ [over.best.ics]p4: 1158 // However, when considering the argument of a user-defined 1159 // conversion function that is a candidate by 13.3.1.3 when 1160 // invoked for the copying of the temporary in the second step 1161 // of a class copy-initialization, or by 13.3.1.4, 13.3.1.5, or 1162 // 13.3.1.6 in all cases, only standard conversion sequences and 1163 // ellipsis conversion sequences are allowed. 1164 if (SuppressUserConversions && ICS.isUserDefined()) { 1165 ICS.setBad(BadConversionSequence::suppressed_user, From, ToType); 1166 } 1167 } else if (UserDefResult == OR_Ambiguous && !SuppressUserConversions) { 1168 ICS.setAmbiguous(); 1169 ICS.Ambiguous.setFromType(From->getType()); 1170 ICS.Ambiguous.setToType(ToType); 1171 for (OverloadCandidateSet::iterator Cand = Conversions.begin(); 1172 Cand != Conversions.end(); ++Cand) 1173 if (Cand->Viable) 1174 ICS.Ambiguous.addConversion(Cand->Function); 1175 } else { 1176 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 1177 } 1178 1179 return ICS; 1180 } 1181 1182 /// TryImplicitConversion - Attempt to perform an implicit conversion 1183 /// from the given expression (Expr) to the given type (ToType). This 1184 /// function returns an implicit conversion sequence that can be used 1185 /// to perform the initialization. Given 1186 /// 1187 /// void f(float f); 1188 /// void g(int i) { f(i); } 1189 /// 1190 /// this routine would produce an implicit conversion sequence to 1191 /// describe the initialization of f from i, which will be a standard 1192 /// conversion sequence containing an lvalue-to-rvalue conversion (C++ 1193 /// 4.1) followed by a floating-integral conversion (C++ 4.9). 1194 // 1195 /// Note that this routine only determines how the conversion can be 1196 /// performed; it does not actually perform the conversion. As such, 1197 /// it will not produce any diagnostics if no conversion is available, 1198 /// but will instead return an implicit conversion sequence of kind 1199 /// "BadConversion". 1200 /// 1201 /// If @p SuppressUserConversions, then user-defined conversions are 1202 /// not permitted. 1203 /// If @p AllowExplicit, then explicit user-defined conversions are 1204 /// permitted. 1205 /// 1206 /// \param AllowObjCWritebackConversion Whether we allow the Objective-C 1207 /// writeback conversion, which allows __autoreleasing id* parameters to 1208 /// be initialized with __strong id* or __weak id* arguments. 1209 static ImplicitConversionSequence 1210 TryImplicitConversion(Sema &S, Expr *From, QualType ToType, 1211 bool SuppressUserConversions, 1212 bool AllowExplicit, 1213 bool InOverloadResolution, 1214 bool CStyle, 1215 bool AllowObjCWritebackConversion) { 1216 ImplicitConversionSequence ICS; 1217 if (IsStandardConversion(S, From, ToType, InOverloadResolution, 1218 ICS.Standard, CStyle, AllowObjCWritebackConversion)){ 1219 ICS.setStandard(); 1220 return ICS; 1221 } 1222 1223 if (!S.getLangOpts().CPlusPlus) { 1224 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 1225 return ICS; 1226 } 1227 1228 // C++ [over.ics.user]p4: 1229 // A conversion of an expression of class type to the same class 1230 // type is given Exact Match rank, and a conversion of an 1231 // expression of class type to a base class of that type is 1232 // given Conversion rank, in spite of the fact that a copy/move 1233 // constructor (i.e., a user-defined conversion function) is 1234 // called for those cases. 1235 QualType FromType = From->getType(); 1236 if (ToType->getAs<RecordType>() && FromType->getAs<RecordType>() && 1237 (S.Context.hasSameUnqualifiedType(FromType, ToType) || 1238 S.IsDerivedFrom(FromType, ToType))) { 1239 ICS.setStandard(); 1240 ICS.Standard.setAsIdentityConversion(); 1241 ICS.Standard.setFromType(FromType); 1242 ICS.Standard.setAllToTypes(ToType); 1243 1244 // We don't actually check at this point whether there is a valid 1245 // copy/move constructor, since overloading just assumes that it 1246 // exists. When we actually perform initialization, we'll find the 1247 // appropriate constructor to copy the returned object, if needed. 1248 ICS.Standard.CopyConstructor = 0; 1249 1250 // Determine whether this is considered a derived-to-base conversion. 1251 if (!S.Context.hasSameUnqualifiedType(FromType, ToType)) 1252 ICS.Standard.Second = ICK_Derived_To_Base; 1253 1254 return ICS; 1255 } 1256 1257 return TryUserDefinedConversion(S, From, ToType, SuppressUserConversions, 1258 AllowExplicit, InOverloadResolution, CStyle, 1259 AllowObjCWritebackConversion); 1260 } 1261 1262 ImplicitConversionSequence 1263 Sema::TryImplicitConversion(Expr *From, QualType ToType, 1264 bool SuppressUserConversions, 1265 bool AllowExplicit, 1266 bool InOverloadResolution, 1267 bool CStyle, 1268 bool AllowObjCWritebackConversion) { 1269 return clang::TryImplicitConversion(*this, From, ToType, 1270 SuppressUserConversions, AllowExplicit, 1271 InOverloadResolution, CStyle, 1272 AllowObjCWritebackConversion); 1273 } 1274 1275 /// PerformImplicitConversion - Perform an implicit conversion of the 1276 /// expression From to the type ToType. Returns the 1277 /// converted expression. Flavor is the kind of conversion we're 1278 /// performing, used in the error message. If @p AllowExplicit, 1279 /// explicit user-defined conversions are permitted. 1280 ExprResult 1281 Sema::PerformImplicitConversion(Expr *From, QualType ToType, 1282 AssignmentAction Action, bool AllowExplicit) { 1283 ImplicitConversionSequence ICS; 1284 return PerformImplicitConversion(From, ToType, Action, AllowExplicit, ICS); 1285 } 1286 1287 ExprResult 1288 Sema::PerformImplicitConversion(Expr *From, QualType ToType, 1289 AssignmentAction Action, bool AllowExplicit, 1290 ImplicitConversionSequence& ICS) { 1291 if (checkPlaceholderForOverload(*this, From)) 1292 return ExprError(); 1293 1294 // Objective-C ARC: Determine whether we will allow the writeback conversion. 1295 bool AllowObjCWritebackConversion 1296 = getLangOpts().ObjCAutoRefCount && 1297 (Action == AA_Passing || Action == AA_Sending); 1298 1299 ICS = clang::TryImplicitConversion(*this, From, ToType, 1300 /*SuppressUserConversions=*/false, 1301 AllowExplicit, 1302 /*InOverloadResolution=*/false, 1303 /*CStyle=*/false, 1304 AllowObjCWritebackConversion); 1305 return PerformImplicitConversion(From, ToType, ICS, Action); 1306 } 1307 1308 /// \brief Determine whether the conversion from FromType to ToType is a valid 1309 /// conversion that strips "noreturn" off the nested function type. 1310 bool Sema::IsNoReturnConversion(QualType FromType, QualType ToType, 1311 QualType &ResultTy) { 1312 if (Context.hasSameUnqualifiedType(FromType, ToType)) 1313 return false; 1314 1315 // Permit the conversion F(t __attribute__((noreturn))) -> F(t) 1316 // where F adds one of the following at most once: 1317 // - a pointer 1318 // - a member pointer 1319 // - a block pointer 1320 CanQualType CanTo = Context.getCanonicalType(ToType); 1321 CanQualType CanFrom = Context.getCanonicalType(FromType); 1322 Type::TypeClass TyClass = CanTo->getTypeClass(); 1323 if (TyClass != CanFrom->getTypeClass()) return false; 1324 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) { 1325 if (TyClass == Type::Pointer) { 1326 CanTo = CanTo.getAs<PointerType>()->getPointeeType(); 1327 CanFrom = CanFrom.getAs<PointerType>()->getPointeeType(); 1328 } else if (TyClass == Type::BlockPointer) { 1329 CanTo = CanTo.getAs<BlockPointerType>()->getPointeeType(); 1330 CanFrom = CanFrom.getAs<BlockPointerType>()->getPointeeType(); 1331 } else if (TyClass == Type::MemberPointer) { 1332 CanTo = CanTo.getAs<MemberPointerType>()->getPointeeType(); 1333 CanFrom = CanFrom.getAs<MemberPointerType>()->getPointeeType(); 1334 } else { 1335 return false; 1336 } 1337 1338 TyClass = CanTo->getTypeClass(); 1339 if (TyClass != CanFrom->getTypeClass()) return false; 1340 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) 1341 return false; 1342 } 1343 1344 const FunctionType *FromFn = cast<FunctionType>(CanFrom); 1345 FunctionType::ExtInfo EInfo = FromFn->getExtInfo(); 1346 if (!EInfo.getNoReturn()) return false; 1347 1348 FromFn = Context.adjustFunctionType(FromFn, EInfo.withNoReturn(false)); 1349 assert(QualType(FromFn, 0).isCanonical()); 1350 if (QualType(FromFn, 0) != CanTo) return false; 1351 1352 ResultTy = ToType; 1353 return true; 1354 } 1355 1356 /// \brief Determine whether the conversion from FromType to ToType is a valid 1357 /// vector conversion. 1358 /// 1359 /// \param ICK Will be set to the vector conversion kind, if this is a vector 1360 /// conversion. 1361 static bool IsVectorConversion(ASTContext &Context, QualType FromType, 1362 QualType ToType, ImplicitConversionKind &ICK) { 1363 // We need at least one of these types to be a vector type to have a vector 1364 // conversion. 1365 if (!ToType->isVectorType() && !FromType->isVectorType()) 1366 return false; 1367 1368 // Identical types require no conversions. 1369 if (Context.hasSameUnqualifiedType(FromType, ToType)) 1370 return false; 1371 1372 // There are no conversions between extended vector types, only identity. 1373 if (ToType->isExtVectorType()) { 1374 // There are no conversions between extended vector types other than the 1375 // identity conversion. 1376 if (FromType->isExtVectorType()) 1377 return false; 1378 1379 // Vector splat from any arithmetic type to a vector. 1380 if (FromType->isArithmeticType()) { 1381 ICK = ICK_Vector_Splat; 1382 return true; 1383 } 1384 } 1385 1386 // We can perform the conversion between vector types in the following cases: 1387 // 1)vector types are equivalent AltiVec and GCC vector types 1388 // 2)lax vector conversions are permitted and the vector types are of the 1389 // same size 1390 if (ToType->isVectorType() && FromType->isVectorType()) { 1391 if (Context.areCompatibleVectorTypes(FromType, ToType) || 1392 (Context.getLangOpts().LaxVectorConversions && 1393 (Context.getTypeSize(FromType) == Context.getTypeSize(ToType)))) { 1394 ICK = ICK_Vector_Conversion; 1395 return true; 1396 } 1397 } 1398 1399 return false; 1400 } 1401 1402 static bool tryAtomicConversion(Sema &S, Expr *From, QualType ToType, 1403 bool InOverloadResolution, 1404 StandardConversionSequence &SCS, 1405 bool CStyle); 1406 1407 /// IsStandardConversion - Determines whether there is a standard 1408 /// conversion sequence (C++ [conv], C++ [over.ics.scs]) from the 1409 /// expression From to the type ToType. Standard conversion sequences 1410 /// only consider non-class types; for conversions that involve class 1411 /// types, use TryImplicitConversion. If a conversion exists, SCS will 1412 /// contain the standard conversion sequence required to perform this 1413 /// conversion and this routine will return true. Otherwise, this 1414 /// routine will return false and the value of SCS is unspecified. 1415 static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType, 1416 bool InOverloadResolution, 1417 StandardConversionSequence &SCS, 1418 bool CStyle, 1419 bool AllowObjCWritebackConversion) { 1420 QualType FromType = From->getType(); 1421 1422 // Standard conversions (C++ [conv]) 1423 SCS.setAsIdentityConversion(); 1424 SCS.DeprecatedStringLiteralToCharPtr = false; 1425 SCS.IncompatibleObjC = false; 1426 SCS.setFromType(FromType); 1427 SCS.CopyConstructor = 0; 1428 1429 // There are no standard conversions for class types in C++, so 1430 // abort early. When overloading in C, however, we do permit 1431 if (FromType->isRecordType() || ToType->isRecordType()) { 1432 if (S.getLangOpts().CPlusPlus) 1433 return false; 1434 1435 // When we're overloading in C, we allow, as standard conversions, 1436 } 1437 1438 // The first conversion can be an lvalue-to-rvalue conversion, 1439 // array-to-pointer conversion, or function-to-pointer conversion 1440 // (C++ 4p1). 1441 1442 if (FromType == S.Context.OverloadTy) { 1443 DeclAccessPair AccessPair; 1444 if (FunctionDecl *Fn 1445 = S.ResolveAddressOfOverloadedFunction(From, ToType, false, 1446 AccessPair)) { 1447 // We were able to resolve the address of the overloaded function, 1448 // so we can convert to the type of that function. 1449 FromType = Fn->getType(); 1450 1451 // we can sometimes resolve &foo<int> regardless of ToType, so check 1452 // if the type matches (identity) or we are converting to bool 1453 if (!S.Context.hasSameUnqualifiedType( 1454 S.ExtractUnqualifiedFunctionType(ToType), FromType)) { 1455 QualType resultTy; 1456 // if the function type matches except for [[noreturn]], it's ok 1457 if (!S.IsNoReturnConversion(FromType, 1458 S.ExtractUnqualifiedFunctionType(ToType), resultTy)) 1459 // otherwise, only a boolean conversion is standard 1460 if (!ToType->isBooleanType()) 1461 return false; 1462 } 1463 1464 // Check if the "from" expression is taking the address of an overloaded 1465 // function and recompute the FromType accordingly. Take advantage of the 1466 // fact that non-static member functions *must* have such an address-of 1467 // expression. 1468 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn); 1469 if (Method && !Method->isStatic()) { 1470 assert(isa<UnaryOperator>(From->IgnoreParens()) && 1471 "Non-unary operator on non-static member address"); 1472 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() 1473 == UO_AddrOf && 1474 "Non-address-of operator on non-static member address"); 1475 const Type *ClassType 1476 = S.Context.getTypeDeclType(Method->getParent()).getTypePtr(); 1477 FromType = S.Context.getMemberPointerType(FromType, ClassType); 1478 } else if (isa<UnaryOperator>(From->IgnoreParens())) { 1479 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == 1480 UO_AddrOf && 1481 "Non-address-of operator for overloaded function expression"); 1482 FromType = S.Context.getPointerType(FromType); 1483 } 1484 1485 // Check that we've computed the proper type after overload resolution. 1486 assert(S.Context.hasSameType( 1487 FromType, 1488 S.FixOverloadedFunctionReference(From, AccessPair, Fn)->getType())); 1489 } else { 1490 return false; 1491 } 1492 } 1493 // Lvalue-to-rvalue conversion (C++11 4.1): 1494 // A glvalue (3.10) of a non-function, non-array type T can 1495 // be converted to a prvalue. 1496 bool argIsLValue = From->isGLValue(); 1497 if (argIsLValue && 1498 !FromType->isFunctionType() && !FromType->isArrayType() && 1499 S.Context.getCanonicalType(FromType) != S.Context.OverloadTy) { 1500 SCS.First = ICK_Lvalue_To_Rvalue; 1501 1502 // C11 6.3.2.1p2: 1503 // ... if the lvalue has atomic type, the value has the non-atomic version 1504 // of the type of the lvalue ... 1505 if (const AtomicType *Atomic = FromType->getAs<AtomicType>()) 1506 FromType = Atomic->getValueType(); 1507 1508 // If T is a non-class type, the type of the rvalue is the 1509 // cv-unqualified version of T. Otherwise, the type of the rvalue 1510 // is T (C++ 4.1p1). C++ can't get here with class types; in C, we 1511 // just strip the qualifiers because they don't matter. 1512 FromType = FromType.getUnqualifiedType(); 1513 } else if (FromType->isArrayType()) { 1514 // Array-to-pointer conversion (C++ 4.2) 1515 SCS.First = ICK_Array_To_Pointer; 1516 1517 // An lvalue or rvalue of type "array of N T" or "array of unknown 1518 // bound of T" can be converted to an rvalue of type "pointer to 1519 // T" (C++ 4.2p1). 1520 FromType = S.Context.getArrayDecayedType(FromType); 1521 1522 if (S.IsStringLiteralToNonConstPointerConversion(From, ToType)) { 1523 // This conversion is deprecated. (C++ D.4). 1524 SCS.DeprecatedStringLiteralToCharPtr = true; 1525 1526 // For the purpose of ranking in overload resolution 1527 // (13.3.3.1.1), this conversion is considered an 1528 // array-to-pointer conversion followed by a qualification 1529 // conversion (4.4). (C++ 4.2p2) 1530 SCS.Second = ICK_Identity; 1531 SCS.Third = ICK_Qualification; 1532 SCS.QualificationIncludesObjCLifetime = false; 1533 SCS.setAllToTypes(FromType); 1534 return true; 1535 } 1536 } else if (FromType->isFunctionType() && argIsLValue) { 1537 // Function-to-pointer conversion (C++ 4.3). 1538 SCS.First = ICK_Function_To_Pointer; 1539 1540 // An lvalue of function type T can be converted to an rvalue of 1541 // type "pointer to T." The result is a pointer to the 1542 // function. (C++ 4.3p1). 1543 FromType = S.Context.getPointerType(FromType); 1544 } else { 1545 // We don't require any conversions for the first step. 1546 SCS.First = ICK_Identity; 1547 } 1548 SCS.setToType(0, FromType); 1549 1550 // The second conversion can be an integral promotion, floating 1551 // point promotion, integral conversion, floating point conversion, 1552 // floating-integral conversion, pointer conversion, 1553 // pointer-to-member conversion, or boolean conversion (C++ 4p1). 1554 // For overloading in C, this can also be a "compatible-type" 1555 // conversion. 1556 bool IncompatibleObjC = false; 1557 ImplicitConversionKind SecondICK = ICK_Identity; 1558 if (S.Context.hasSameUnqualifiedType(FromType, ToType)) { 1559 // The unqualified versions of the types are the same: there's no 1560 // conversion to do. 1561 SCS.Second = ICK_Identity; 1562 } else if (S.IsIntegralPromotion(From, FromType, ToType)) { 1563 // Integral promotion (C++ 4.5). 1564 SCS.Second = ICK_Integral_Promotion; 1565 FromType = ToType.getUnqualifiedType(); 1566 } else if (S.IsFloatingPointPromotion(FromType, ToType)) { 1567 // Floating point promotion (C++ 4.6). 1568 SCS.Second = ICK_Floating_Promotion; 1569 FromType = ToType.getUnqualifiedType(); 1570 } else if (S.IsComplexPromotion(FromType, ToType)) { 1571 // Complex promotion (Clang extension) 1572 SCS.Second = ICK_Complex_Promotion; 1573 FromType = ToType.getUnqualifiedType(); 1574 } else if (ToType->isBooleanType() && 1575 (FromType->isArithmeticType() || 1576 FromType->isAnyPointerType() || 1577 FromType->isBlockPointerType() || 1578 FromType->isMemberPointerType() || 1579 FromType->isNullPtrType())) { 1580 // Boolean conversions (C++ 4.12). 1581 SCS.Second = ICK_Boolean_Conversion; 1582 FromType = S.Context.BoolTy; 1583 } else if (FromType->isIntegralOrUnscopedEnumerationType() && 1584 ToType->isIntegralType(S.Context)) { 1585 // Integral conversions (C++ 4.7). 1586 SCS.Second = ICK_Integral_Conversion; 1587 FromType = ToType.getUnqualifiedType(); 1588 } else if (FromType->isAnyComplexType() && ToType->isComplexType()) { 1589 // Complex conversions (C99 6.3.1.6) 1590 SCS.Second = ICK_Complex_Conversion; 1591 FromType = ToType.getUnqualifiedType(); 1592 } else if ((FromType->isAnyComplexType() && ToType->isArithmeticType()) || 1593 (ToType->isAnyComplexType() && FromType->isArithmeticType())) { 1594 // Complex-real conversions (C99 6.3.1.7) 1595 SCS.Second = ICK_Complex_Real; 1596 FromType = ToType.getUnqualifiedType(); 1597 } else if (FromType->isRealFloatingType() && ToType->isRealFloatingType()) { 1598 // Floating point conversions (C++ 4.8). 1599 SCS.Second = ICK_Floating_Conversion; 1600 FromType = ToType.getUnqualifiedType(); 1601 } else if ((FromType->isRealFloatingType() && 1602 ToType->isIntegralType(S.Context)) || 1603 (FromType->isIntegralOrUnscopedEnumerationType() && 1604 ToType->isRealFloatingType())) { 1605 // Floating-integral conversions (C++ 4.9). 1606 SCS.Second = ICK_Floating_Integral; 1607 FromType = ToType.getUnqualifiedType(); 1608 } else if (S.IsBlockPointerConversion(FromType, ToType, FromType)) { 1609 SCS.Second = ICK_Block_Pointer_Conversion; 1610 } else if (AllowObjCWritebackConversion && 1611 S.isObjCWritebackConversion(FromType, ToType, FromType)) { 1612 SCS.Second = ICK_Writeback_Conversion; 1613 } else if (S.IsPointerConversion(From, FromType, ToType, InOverloadResolution, 1614 FromType, IncompatibleObjC)) { 1615 // Pointer conversions (C++ 4.10). 1616 SCS.Second = ICK_Pointer_Conversion; 1617 SCS.IncompatibleObjC = IncompatibleObjC; 1618 FromType = FromType.getUnqualifiedType(); 1619 } else if (S.IsMemberPointerConversion(From, FromType, ToType, 1620 InOverloadResolution, FromType)) { 1621 // Pointer to member conversions (4.11). 1622 SCS.Second = ICK_Pointer_Member; 1623 } else if (IsVectorConversion(S.Context, FromType, ToType, SecondICK)) { 1624 SCS.Second = SecondICK; 1625 FromType = ToType.getUnqualifiedType(); 1626 } else if (!S.getLangOpts().CPlusPlus && 1627 S.Context.typesAreCompatible(ToType, FromType)) { 1628 // Compatible conversions (Clang extension for C function overloading) 1629 SCS.Second = ICK_Compatible_Conversion; 1630 FromType = ToType.getUnqualifiedType(); 1631 } else if (S.IsNoReturnConversion(FromType, ToType, FromType)) { 1632 // Treat a conversion that strips "noreturn" as an identity conversion. 1633 SCS.Second = ICK_NoReturn_Adjustment; 1634 } else if (IsTransparentUnionStandardConversion(S, From, ToType, 1635 InOverloadResolution, 1636 SCS, CStyle)) { 1637 SCS.Second = ICK_TransparentUnionConversion; 1638 FromType = ToType; 1639 } else if (tryAtomicConversion(S, From, ToType, InOverloadResolution, SCS, 1640 CStyle)) { 1641 // tryAtomicConversion has updated the standard conversion sequence 1642 // appropriately. 1643 return true; 1644 } else if (ToType->isEventT() && 1645 From->isIntegerConstantExpr(S.getASTContext()) && 1646 (From->EvaluateKnownConstInt(S.getASTContext()) == 0)) { 1647 SCS.Second = ICK_Zero_Event_Conversion; 1648 FromType = ToType; 1649 } else { 1650 // No second conversion required. 1651 SCS.Second = ICK_Identity; 1652 } 1653 SCS.setToType(1, FromType); 1654 1655 QualType CanonFrom; 1656 QualType CanonTo; 1657 // The third conversion can be a qualification conversion (C++ 4p1). 1658 bool ObjCLifetimeConversion; 1659 if (S.IsQualificationConversion(FromType, ToType, CStyle, 1660 ObjCLifetimeConversion)) { 1661 SCS.Third = ICK_Qualification; 1662 SCS.QualificationIncludesObjCLifetime = ObjCLifetimeConversion; 1663 FromType = ToType; 1664 CanonFrom = S.Context.getCanonicalType(FromType); 1665 CanonTo = S.Context.getCanonicalType(ToType); 1666 } else { 1667 // No conversion required 1668 SCS.Third = ICK_Identity; 1669 1670 // C++ [over.best.ics]p6: 1671 // [...] Any difference in top-level cv-qualification is 1672 // subsumed by the initialization itself and does not constitute 1673 // a conversion. [...] 1674 CanonFrom = S.Context.getCanonicalType(FromType); 1675 CanonTo = S.Context.getCanonicalType(ToType); 1676 if (CanonFrom.getLocalUnqualifiedType() 1677 == CanonTo.getLocalUnqualifiedType() && 1678 CanonFrom.getLocalQualifiers() != CanonTo.getLocalQualifiers()) { 1679 FromType = ToType; 1680 CanonFrom = CanonTo; 1681 } 1682 } 1683 SCS.setToType(2, FromType); 1684 1685 // If we have not converted the argument type to the parameter type, 1686 // this is a bad conversion sequence. 1687 if (CanonFrom != CanonTo) 1688 return false; 1689 1690 return true; 1691 } 1692 1693 static bool 1694 IsTransparentUnionStandardConversion(Sema &S, Expr* From, 1695 QualType &ToType, 1696 bool InOverloadResolution, 1697 StandardConversionSequence &SCS, 1698 bool CStyle) { 1699 1700 const RecordType *UT = ToType->getAsUnionType(); 1701 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 1702 return false; 1703 // The field to initialize within the transparent union. 1704 RecordDecl *UD = UT->getDecl(); 1705 // It's compatible if the expression matches any of the fields. 1706 for (RecordDecl::field_iterator it = UD->field_begin(), 1707 itend = UD->field_end(); 1708 it != itend; ++it) { 1709 if (IsStandardConversion(S, From, it->getType(), InOverloadResolution, SCS, 1710 CStyle, /*ObjCWritebackConversion=*/false)) { 1711 ToType = it->getType(); 1712 return true; 1713 } 1714 } 1715 return false; 1716 } 1717 1718 /// IsIntegralPromotion - Determines whether the conversion from the 1719 /// expression From (whose potentially-adjusted type is FromType) to 1720 /// ToType is an integral promotion (C++ 4.5). If so, returns true and 1721 /// sets PromotedType to the promoted type. 1722 bool Sema::IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType) { 1723 const BuiltinType *To = ToType->getAs<BuiltinType>(); 1724 // All integers are built-in. 1725 if (!To) { 1726 return false; 1727 } 1728 1729 // An rvalue of type char, signed char, unsigned char, short int, or 1730 // unsigned short int can be converted to an rvalue of type int if 1731 // int can represent all the values of the source type; otherwise, 1732 // the source rvalue can be converted to an rvalue of type unsigned 1733 // int (C++ 4.5p1). 1734 if (FromType->isPromotableIntegerType() && !FromType->isBooleanType() && 1735 !FromType->isEnumeralType()) { 1736 if (// We can promote any signed, promotable integer type to an int 1737 (FromType->isSignedIntegerType() || 1738 // We can promote any unsigned integer type whose size is 1739 // less than int to an int. 1740 (!FromType->isSignedIntegerType() && 1741 Context.getTypeSize(FromType) < Context.getTypeSize(ToType)))) { 1742 return To->getKind() == BuiltinType::Int; 1743 } 1744 1745 return To->getKind() == BuiltinType::UInt; 1746 } 1747 1748 // C++11 [conv.prom]p3: 1749 // A prvalue of an unscoped enumeration type whose underlying type is not 1750 // fixed (7.2) can be converted to an rvalue a prvalue of the first of the 1751 // following types that can represent all the values of the enumeration 1752 // (i.e., the values in the range bmin to bmax as described in 7.2): int, 1753 // unsigned int, long int, unsigned long int, long long int, or unsigned 1754 // long long int. If none of the types in that list can represent all the 1755 // values of the enumeration, an rvalue a prvalue of an unscoped enumeration 1756 // type can be converted to an rvalue a prvalue of the extended integer type 1757 // with lowest integer conversion rank (4.13) greater than the rank of long 1758 // long in which all the values of the enumeration can be represented. If 1759 // there are two such extended types, the signed one is chosen. 1760 // C++11 [conv.prom]p4: 1761 // A prvalue of an unscoped enumeration type whose underlying type is fixed 1762 // can be converted to a prvalue of its underlying type. Moreover, if 1763 // integral promotion can be applied to its underlying type, a prvalue of an 1764 // unscoped enumeration type whose underlying type is fixed can also be 1765 // converted to a prvalue of the promoted underlying type. 1766 if (const EnumType *FromEnumType = FromType->getAs<EnumType>()) { 1767 // C++0x 7.2p9: Note that this implicit enum to int conversion is not 1768 // provided for a scoped enumeration. 1769 if (FromEnumType->getDecl()->isScoped()) 1770 return false; 1771 1772 // We can perform an integral promotion to the underlying type of the enum, 1773 // even if that's not the promoted type. 1774 if (FromEnumType->getDecl()->isFixed()) { 1775 QualType Underlying = FromEnumType->getDecl()->getIntegerType(); 1776 return Context.hasSameUnqualifiedType(Underlying, ToType) || 1777 IsIntegralPromotion(From, Underlying, ToType); 1778 } 1779 1780 // We have already pre-calculated the promotion type, so this is trivial. 1781 if (ToType->isIntegerType() && 1782 !RequireCompleteType(From->getLocStart(), FromType, 0)) 1783 return Context.hasSameUnqualifiedType(ToType, 1784 FromEnumType->getDecl()->getPromotionType()); 1785 } 1786 1787 // C++0x [conv.prom]p2: 1788 // A prvalue of type char16_t, char32_t, or wchar_t (3.9.1) can be converted 1789 // to an rvalue a prvalue of the first of the following types that can 1790 // represent all the values of its underlying type: int, unsigned int, 1791 // long int, unsigned long int, long long int, or unsigned long long int. 1792 // If none of the types in that list can represent all the values of its 1793 // underlying type, an rvalue a prvalue of type char16_t, char32_t, 1794 // or wchar_t can be converted to an rvalue a prvalue of its underlying 1795 // type. 1796 if (FromType->isAnyCharacterType() && !FromType->isCharType() && 1797 ToType->isIntegerType()) { 1798 // Determine whether the type we're converting from is signed or 1799 // unsigned. 1800 bool FromIsSigned = FromType->isSignedIntegerType(); 1801 uint64_t FromSize = Context.getTypeSize(FromType); 1802 1803 // The types we'll try to promote to, in the appropriate 1804 // order. Try each of these types. 1805 QualType PromoteTypes[6] = { 1806 Context.IntTy, Context.UnsignedIntTy, 1807 Context.LongTy, Context.UnsignedLongTy , 1808 Context.LongLongTy, Context.UnsignedLongLongTy 1809 }; 1810 for (int Idx = 0; Idx < 6; ++Idx) { 1811 uint64_t ToSize = Context.getTypeSize(PromoteTypes[Idx]); 1812 if (FromSize < ToSize || 1813 (FromSize == ToSize && 1814 FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType())) { 1815 // We found the type that we can promote to. If this is the 1816 // type we wanted, we have a promotion. Otherwise, no 1817 // promotion. 1818 return Context.hasSameUnqualifiedType(ToType, PromoteTypes[Idx]); 1819 } 1820 } 1821 } 1822 1823 // An rvalue for an integral bit-field (9.6) can be converted to an 1824 // rvalue of type int if int can represent all the values of the 1825 // bit-field; otherwise, it can be converted to unsigned int if 1826 // unsigned int can represent all the values of the bit-field. If 1827 // the bit-field is larger yet, no integral promotion applies to 1828 // it. If the bit-field has an enumerated type, it is treated as any 1829 // other value of that type for promotion purposes (C++ 4.5p3). 1830 // FIXME: We should delay checking of bit-fields until we actually perform the 1831 // conversion. 1832 using llvm::APSInt; 1833 if (From) 1834 if (FieldDecl *MemberDecl = From->getBitField()) { 1835 APSInt BitWidth; 1836 if (FromType->isIntegralType(Context) && 1837 MemberDecl->getBitWidth()->isIntegerConstantExpr(BitWidth, Context)) { 1838 APSInt ToSize(BitWidth.getBitWidth(), BitWidth.isUnsigned()); 1839 ToSize = Context.getTypeSize(ToType); 1840 1841 // Are we promoting to an int from a bitfield that fits in an int? 1842 if (BitWidth < ToSize || 1843 (FromType->isSignedIntegerType() && BitWidth <= ToSize)) { 1844 return To->getKind() == BuiltinType::Int; 1845 } 1846 1847 // Are we promoting to an unsigned int from an unsigned bitfield 1848 // that fits into an unsigned int? 1849 if (FromType->isUnsignedIntegerType() && BitWidth <= ToSize) { 1850 return To->getKind() == BuiltinType::UInt; 1851 } 1852 1853 return false; 1854 } 1855 } 1856 1857 // An rvalue of type bool can be converted to an rvalue of type int, 1858 // with false becoming zero and true becoming one (C++ 4.5p4). 1859 if (FromType->isBooleanType() && To->getKind() == BuiltinType::Int) { 1860 return true; 1861 } 1862 1863 return false; 1864 } 1865 1866 /// IsFloatingPointPromotion - Determines whether the conversion from 1867 /// FromType to ToType is a floating point promotion (C++ 4.6). If so, 1868 /// returns true and sets PromotedType to the promoted type. 1869 bool Sema::IsFloatingPointPromotion(QualType FromType, QualType ToType) { 1870 if (const BuiltinType *FromBuiltin = FromType->getAs<BuiltinType>()) 1871 if (const BuiltinType *ToBuiltin = ToType->getAs<BuiltinType>()) { 1872 /// An rvalue of type float can be converted to an rvalue of type 1873 /// double. (C++ 4.6p1). 1874 if (FromBuiltin->getKind() == BuiltinType::Float && 1875 ToBuiltin->getKind() == BuiltinType::Double) 1876 return true; 1877 1878 // C99 6.3.1.5p1: 1879 // When a float is promoted to double or long double, or a 1880 // double is promoted to long double [...]. 1881 if (!getLangOpts().CPlusPlus && 1882 (FromBuiltin->getKind() == BuiltinType::Float || 1883 FromBuiltin->getKind() == BuiltinType::Double) && 1884 (ToBuiltin->getKind() == BuiltinType::LongDouble)) 1885 return true; 1886 1887 // Half can be promoted to float. 1888 if (!getLangOpts().NativeHalfType && 1889 FromBuiltin->getKind() == BuiltinType::Half && 1890 ToBuiltin->getKind() == BuiltinType::Float) 1891 return true; 1892 } 1893 1894 return false; 1895 } 1896 1897 /// \brief Determine if a conversion is a complex promotion. 1898 /// 1899 /// A complex promotion is defined as a complex -> complex conversion 1900 /// where the conversion between the underlying real types is a 1901 /// floating-point or integral promotion. 1902 bool Sema::IsComplexPromotion(QualType FromType, QualType ToType) { 1903 const ComplexType *FromComplex = FromType->getAs<ComplexType>(); 1904 if (!FromComplex) 1905 return false; 1906 1907 const ComplexType *ToComplex = ToType->getAs<ComplexType>(); 1908 if (!ToComplex) 1909 return false; 1910 1911 return IsFloatingPointPromotion(FromComplex->getElementType(), 1912 ToComplex->getElementType()) || 1913 IsIntegralPromotion(0, FromComplex->getElementType(), 1914 ToComplex->getElementType()); 1915 } 1916 1917 /// BuildSimilarlyQualifiedPointerType - In a pointer conversion from 1918 /// the pointer type FromPtr to a pointer to type ToPointee, with the 1919 /// same type qualifiers as FromPtr has on its pointee type. ToType, 1920 /// if non-empty, will be a pointer to ToType that may or may not have 1921 /// the right set of qualifiers on its pointee. 1922 /// 1923 static QualType 1924 BuildSimilarlyQualifiedPointerType(const Type *FromPtr, 1925 QualType ToPointee, QualType ToType, 1926 ASTContext &Context, 1927 bool StripObjCLifetime = false) { 1928 assert((FromPtr->getTypeClass() == Type::Pointer || 1929 FromPtr->getTypeClass() == Type::ObjCObjectPointer) && 1930 "Invalid similarly-qualified pointer type"); 1931 1932 /// Conversions to 'id' subsume cv-qualifier conversions. 1933 if (ToType->isObjCIdType() || ToType->isObjCQualifiedIdType()) 1934 return ToType.getUnqualifiedType(); 1935 1936 QualType CanonFromPointee 1937 = Context.getCanonicalType(FromPtr->getPointeeType()); 1938 QualType CanonToPointee = Context.getCanonicalType(ToPointee); 1939 Qualifiers Quals = CanonFromPointee.getQualifiers(); 1940 1941 if (StripObjCLifetime) 1942 Quals.removeObjCLifetime(); 1943 1944 // Exact qualifier match -> return the pointer type we're converting to. 1945 if (CanonToPointee.getLocalQualifiers() == Quals) { 1946 // ToType is exactly what we need. Return it. 1947 if (!ToType.isNull()) 1948 return ToType.getUnqualifiedType(); 1949 1950 // Build a pointer to ToPointee. It has the right qualifiers 1951 // already. 1952 if (isa<ObjCObjectPointerType>(ToType)) 1953 return Context.getObjCObjectPointerType(ToPointee); 1954 return Context.getPointerType(ToPointee); 1955 } 1956 1957 // Just build a canonical type that has the right qualifiers. 1958 QualType QualifiedCanonToPointee 1959 = Context.getQualifiedType(CanonToPointee.getLocalUnqualifiedType(), Quals); 1960 1961 if (isa<ObjCObjectPointerType>(ToType)) 1962 return Context.getObjCObjectPointerType(QualifiedCanonToPointee); 1963 return Context.getPointerType(QualifiedCanonToPointee); 1964 } 1965 1966 static bool isNullPointerConstantForConversion(Expr *Expr, 1967 bool InOverloadResolution, 1968 ASTContext &Context) { 1969 // Handle value-dependent integral null pointer constants correctly. 1970 // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#903 1971 if (Expr->isValueDependent() && !Expr->isTypeDependent() && 1972 Expr->getType()->isIntegerType() && !Expr->getType()->isEnumeralType()) 1973 return !InOverloadResolution; 1974 1975 return Expr->isNullPointerConstant(Context, 1976 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 1977 : Expr::NPC_ValueDependentIsNull); 1978 } 1979 1980 /// IsPointerConversion - Determines whether the conversion of the 1981 /// expression From, which has the (possibly adjusted) type FromType, 1982 /// can be converted to the type ToType via a pointer conversion (C++ 1983 /// 4.10). If so, returns true and places the converted type (that 1984 /// might differ from ToType in its cv-qualifiers at some level) into 1985 /// ConvertedType. 1986 /// 1987 /// This routine also supports conversions to and from block pointers 1988 /// and conversions with Objective-C's 'id', 'id<protocols...>', and 1989 /// pointers to interfaces. FIXME: Once we've determined the 1990 /// appropriate overloading rules for Objective-C, we may want to 1991 /// split the Objective-C checks into a different routine; however, 1992 /// GCC seems to consider all of these conversions to be pointer 1993 /// conversions, so for now they live here. IncompatibleObjC will be 1994 /// set if the conversion is an allowed Objective-C conversion that 1995 /// should result in a warning. 1996 bool Sema::IsPointerConversion(Expr *From, QualType FromType, QualType ToType, 1997 bool InOverloadResolution, 1998 QualType& ConvertedType, 1999 bool &IncompatibleObjC) { 2000 IncompatibleObjC = false; 2001 if (isObjCPointerConversion(FromType, ToType, ConvertedType, 2002 IncompatibleObjC)) 2003 return true; 2004 2005 // Conversion from a null pointer constant to any Objective-C pointer type. 2006 if (ToType->isObjCObjectPointerType() && 2007 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 2008 ConvertedType = ToType; 2009 return true; 2010 } 2011 2012 // Blocks: Block pointers can be converted to void*. 2013 if (FromType->isBlockPointerType() && ToType->isPointerType() && 2014 ToType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 2015 ConvertedType = ToType; 2016 return true; 2017 } 2018 // Blocks: A null pointer constant can be converted to a block 2019 // pointer type. 2020 if (ToType->isBlockPointerType() && 2021 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 2022 ConvertedType = ToType; 2023 return true; 2024 } 2025 2026 // If the left-hand-side is nullptr_t, the right side can be a null 2027 // pointer constant. 2028 if (ToType->isNullPtrType() && 2029 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 2030 ConvertedType = ToType; 2031 return true; 2032 } 2033 2034 const PointerType* ToTypePtr = ToType->getAs<PointerType>(); 2035 if (!ToTypePtr) 2036 return false; 2037 2038 // A null pointer constant can be converted to a pointer type (C++ 4.10p1). 2039 if (isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 2040 ConvertedType = ToType; 2041 return true; 2042 } 2043 2044 // Beyond this point, both types need to be pointers 2045 // , including objective-c pointers. 2046 QualType ToPointeeType = ToTypePtr->getPointeeType(); 2047 if (FromType->isObjCObjectPointerType() && ToPointeeType->isVoidType() && 2048 !getLangOpts().ObjCAutoRefCount) { 2049 ConvertedType = BuildSimilarlyQualifiedPointerType( 2050 FromType->getAs<ObjCObjectPointerType>(), 2051 ToPointeeType, 2052 ToType, Context); 2053 return true; 2054 } 2055 const PointerType *FromTypePtr = FromType->getAs<PointerType>(); 2056 if (!FromTypePtr) 2057 return false; 2058 2059 QualType FromPointeeType = FromTypePtr->getPointeeType(); 2060 2061 // If the unqualified pointee types are the same, this can't be a 2062 // pointer conversion, so don't do all of the work below. 2063 if (Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) 2064 return false; 2065 2066 // An rvalue of type "pointer to cv T," where T is an object type, 2067 // can be converted to an rvalue of type "pointer to cv void" (C++ 2068 // 4.10p2). 2069 if (FromPointeeType->isIncompleteOrObjectType() && 2070 ToPointeeType->isVoidType()) { 2071 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 2072 ToPointeeType, 2073 ToType, Context, 2074 /*StripObjCLifetime=*/true); 2075 return true; 2076 } 2077 2078 // MSVC allows implicit function to void* type conversion. 2079 if (getLangOpts().MicrosoftExt && FromPointeeType->isFunctionType() && 2080 ToPointeeType->isVoidType()) { 2081 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 2082 ToPointeeType, 2083 ToType, Context); 2084 return true; 2085 } 2086 2087 // When we're overloading in C, we allow a special kind of pointer 2088 // conversion for compatible-but-not-identical pointee types. 2089 if (!getLangOpts().CPlusPlus && 2090 Context.typesAreCompatible(FromPointeeType, ToPointeeType)) { 2091 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 2092 ToPointeeType, 2093 ToType, Context); 2094 return true; 2095 } 2096 2097 // C++ [conv.ptr]p3: 2098 // 2099 // An rvalue of type "pointer to cv D," where D is a class type, 2100 // can be converted to an rvalue of type "pointer to cv B," where 2101 // B is a base class (clause 10) of D. If B is an inaccessible 2102 // (clause 11) or ambiguous (10.2) base class of D, a program that 2103 // necessitates this conversion is ill-formed. The result of the 2104 // conversion is a pointer to the base class sub-object of the 2105 // derived class object. The null pointer value is converted to 2106 // the null pointer value of the destination type. 2107 // 2108 // Note that we do not check for ambiguity or inaccessibility 2109 // here. That is handled by CheckPointerConversion. 2110 if (getLangOpts().CPlusPlus && 2111 FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 2112 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType) && 2113 !RequireCompleteType(From->getLocStart(), FromPointeeType, 0) && 2114 IsDerivedFrom(FromPointeeType, ToPointeeType)) { 2115 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 2116 ToPointeeType, 2117 ToType, Context); 2118 return true; 2119 } 2120 2121 if (FromPointeeType->isVectorType() && ToPointeeType->isVectorType() && 2122 Context.areCompatibleVectorTypes(FromPointeeType, ToPointeeType)) { 2123 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 2124 ToPointeeType, 2125 ToType, Context); 2126 return true; 2127 } 2128 2129 return false; 2130 } 2131 2132 /// \brief Adopt the given qualifiers for the given type. 2133 static QualType AdoptQualifiers(ASTContext &Context, QualType T, Qualifiers Qs){ 2134 Qualifiers TQs = T.getQualifiers(); 2135 2136 // Check whether qualifiers already match. 2137 if (TQs == Qs) 2138 return T; 2139 2140 if (Qs.compatiblyIncludes(TQs)) 2141 return Context.getQualifiedType(T, Qs); 2142 2143 return Context.getQualifiedType(T.getUnqualifiedType(), Qs); 2144 } 2145 2146 /// isObjCPointerConversion - Determines whether this is an 2147 /// Objective-C pointer conversion. Subroutine of IsPointerConversion, 2148 /// with the same arguments and return values. 2149 bool Sema::isObjCPointerConversion(QualType FromType, QualType ToType, 2150 QualType& ConvertedType, 2151 bool &IncompatibleObjC) { 2152 if (!getLangOpts().ObjC1) 2153 return false; 2154 2155 // The set of qualifiers on the type we're converting from. 2156 Qualifiers FromQualifiers = FromType.getQualifiers(); 2157 2158 // First, we handle all conversions on ObjC object pointer types. 2159 const ObjCObjectPointerType* ToObjCPtr = 2160 ToType->getAs<ObjCObjectPointerType>(); 2161 const ObjCObjectPointerType *FromObjCPtr = 2162 FromType->getAs<ObjCObjectPointerType>(); 2163 2164 if (ToObjCPtr && FromObjCPtr) { 2165 // If the pointee types are the same (ignoring qualifications), 2166 // then this is not a pointer conversion. 2167 if (Context.hasSameUnqualifiedType(ToObjCPtr->getPointeeType(), 2168 FromObjCPtr->getPointeeType())) 2169 return false; 2170 2171 // Check for compatible 2172 // Objective C++: We're able to convert between "id" or "Class" and a 2173 // pointer to any interface (in both directions). 2174 if (ToObjCPtr->isObjCBuiltinType() && FromObjCPtr->isObjCBuiltinType()) { 2175 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 2176 return true; 2177 } 2178 // Conversions with Objective-C's id<...>. 2179 if ((FromObjCPtr->isObjCQualifiedIdType() || 2180 ToObjCPtr->isObjCQualifiedIdType()) && 2181 Context.ObjCQualifiedIdTypesAreCompatible(ToType, FromType, 2182 /*compare=*/false)) { 2183 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 2184 return true; 2185 } 2186 // Objective C++: We're able to convert from a pointer to an 2187 // interface to a pointer to a different interface. 2188 if (Context.canAssignObjCInterfaces(ToObjCPtr, FromObjCPtr)) { 2189 const ObjCInterfaceType* LHS = ToObjCPtr->getInterfaceType(); 2190 const ObjCInterfaceType* RHS = FromObjCPtr->getInterfaceType(); 2191 if (getLangOpts().CPlusPlus && LHS && RHS && 2192 !ToObjCPtr->getPointeeType().isAtLeastAsQualifiedAs( 2193 FromObjCPtr->getPointeeType())) 2194 return false; 2195 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 2196 ToObjCPtr->getPointeeType(), 2197 ToType, Context); 2198 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 2199 return true; 2200 } 2201 2202 if (Context.canAssignObjCInterfaces(FromObjCPtr, ToObjCPtr)) { 2203 // Okay: this is some kind of implicit downcast of Objective-C 2204 // interfaces, which is permitted. However, we're going to 2205 // complain about it. 2206 IncompatibleObjC = true; 2207 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 2208 ToObjCPtr->getPointeeType(), 2209 ToType, Context); 2210 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 2211 return true; 2212 } 2213 } 2214 // Beyond this point, both types need to be C pointers or block pointers. 2215 QualType ToPointeeType; 2216 if (const PointerType *ToCPtr = ToType->getAs<PointerType>()) 2217 ToPointeeType = ToCPtr->getPointeeType(); 2218 else if (const BlockPointerType *ToBlockPtr = 2219 ToType->getAs<BlockPointerType>()) { 2220 // Objective C++: We're able to convert from a pointer to any object 2221 // to a block pointer type. 2222 if (FromObjCPtr && FromObjCPtr->isObjCBuiltinType()) { 2223 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 2224 return true; 2225 } 2226 ToPointeeType = ToBlockPtr->getPointeeType(); 2227 } 2228 else if (FromType->getAs<BlockPointerType>() && 2229 ToObjCPtr && ToObjCPtr->isObjCBuiltinType()) { 2230 // Objective C++: We're able to convert from a block pointer type to a 2231 // pointer to any object. 2232 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 2233 return true; 2234 } 2235 else 2236 return false; 2237 2238 QualType FromPointeeType; 2239 if (const PointerType *FromCPtr = FromType->getAs<PointerType>()) 2240 FromPointeeType = FromCPtr->getPointeeType(); 2241 else if (const BlockPointerType *FromBlockPtr = 2242 FromType->getAs<BlockPointerType>()) 2243 FromPointeeType = FromBlockPtr->getPointeeType(); 2244 else 2245 return false; 2246 2247 // If we have pointers to pointers, recursively check whether this 2248 // is an Objective-C conversion. 2249 if (FromPointeeType->isPointerType() && ToPointeeType->isPointerType() && 2250 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 2251 IncompatibleObjC)) { 2252 // We always complain about this conversion. 2253 IncompatibleObjC = true; 2254 ConvertedType = Context.getPointerType(ConvertedType); 2255 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 2256 return true; 2257 } 2258 // Allow conversion of pointee being objective-c pointer to another one; 2259 // as in I* to id. 2260 if (FromPointeeType->getAs<ObjCObjectPointerType>() && 2261 ToPointeeType->getAs<ObjCObjectPointerType>() && 2262 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 2263 IncompatibleObjC)) { 2264 2265 ConvertedType = Context.getPointerType(ConvertedType); 2266 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 2267 return true; 2268 } 2269 2270 // If we have pointers to functions or blocks, check whether the only 2271 // differences in the argument and result types are in Objective-C 2272 // pointer conversions. If so, we permit the conversion (but 2273 // complain about it). 2274 const FunctionProtoType *FromFunctionType 2275 = FromPointeeType->getAs<FunctionProtoType>(); 2276 const FunctionProtoType *ToFunctionType 2277 = ToPointeeType->getAs<FunctionProtoType>(); 2278 if (FromFunctionType && ToFunctionType) { 2279 // If the function types are exactly the same, this isn't an 2280 // Objective-C pointer conversion. 2281 if (Context.getCanonicalType(FromPointeeType) 2282 == Context.getCanonicalType(ToPointeeType)) 2283 return false; 2284 2285 // Perform the quick checks that will tell us whether these 2286 // function types are obviously different. 2287 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 2288 FromFunctionType->isVariadic() != ToFunctionType->isVariadic() || 2289 FromFunctionType->getTypeQuals() != ToFunctionType->getTypeQuals()) 2290 return false; 2291 2292 bool HasObjCConversion = false; 2293 if (Context.getCanonicalType(FromFunctionType->getResultType()) 2294 == Context.getCanonicalType(ToFunctionType->getResultType())) { 2295 // Okay, the types match exactly. Nothing to do. 2296 } else if (isObjCPointerConversion(FromFunctionType->getResultType(), 2297 ToFunctionType->getResultType(), 2298 ConvertedType, IncompatibleObjC)) { 2299 // Okay, we have an Objective-C pointer conversion. 2300 HasObjCConversion = true; 2301 } else { 2302 // Function types are too different. Abort. 2303 return false; 2304 } 2305 2306 // Check argument types. 2307 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 2308 ArgIdx != NumArgs; ++ArgIdx) { 2309 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 2310 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 2311 if (Context.getCanonicalType(FromArgType) 2312 == Context.getCanonicalType(ToArgType)) { 2313 // Okay, the types match exactly. Nothing to do. 2314 } else if (isObjCPointerConversion(FromArgType, ToArgType, 2315 ConvertedType, IncompatibleObjC)) { 2316 // Okay, we have an Objective-C pointer conversion. 2317 HasObjCConversion = true; 2318 } else { 2319 // Argument types are too different. Abort. 2320 return false; 2321 } 2322 } 2323 2324 if (HasObjCConversion) { 2325 // We had an Objective-C conversion. Allow this pointer 2326 // conversion, but complain about it. 2327 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 2328 IncompatibleObjC = true; 2329 return true; 2330 } 2331 } 2332 2333 return false; 2334 } 2335 2336 /// \brief Determine whether this is an Objective-C writeback conversion, 2337 /// used for parameter passing when performing automatic reference counting. 2338 /// 2339 /// \param FromType The type we're converting form. 2340 /// 2341 /// \param ToType The type we're converting to. 2342 /// 2343 /// \param ConvertedType The type that will be produced after applying 2344 /// this conversion. 2345 bool Sema::isObjCWritebackConversion(QualType FromType, QualType ToType, 2346 QualType &ConvertedType) { 2347 if (!getLangOpts().ObjCAutoRefCount || 2348 Context.hasSameUnqualifiedType(FromType, ToType)) 2349 return false; 2350 2351 // Parameter must be a pointer to __autoreleasing (with no other qualifiers). 2352 QualType ToPointee; 2353 if (const PointerType *ToPointer = ToType->getAs<PointerType>()) 2354 ToPointee = ToPointer->getPointeeType(); 2355 else 2356 return false; 2357 2358 Qualifiers ToQuals = ToPointee.getQualifiers(); 2359 if (!ToPointee->isObjCLifetimeType() || 2360 ToQuals.getObjCLifetime() != Qualifiers::OCL_Autoreleasing || 2361 !ToQuals.withoutObjCLifetime().empty()) 2362 return false; 2363 2364 // Argument must be a pointer to __strong to __weak. 2365 QualType FromPointee; 2366 if (const PointerType *FromPointer = FromType->getAs<PointerType>()) 2367 FromPointee = FromPointer->getPointeeType(); 2368 else 2369 return false; 2370 2371 Qualifiers FromQuals = FromPointee.getQualifiers(); 2372 if (!FromPointee->isObjCLifetimeType() || 2373 (FromQuals.getObjCLifetime() != Qualifiers::OCL_Strong && 2374 FromQuals.getObjCLifetime() != Qualifiers::OCL_Weak)) 2375 return false; 2376 2377 // Make sure that we have compatible qualifiers. 2378 FromQuals.setObjCLifetime(Qualifiers::OCL_Autoreleasing); 2379 if (!ToQuals.compatiblyIncludes(FromQuals)) 2380 return false; 2381 2382 // Remove qualifiers from the pointee type we're converting from; they 2383 // aren't used in the compatibility check belong, and we'll be adding back 2384 // qualifiers (with __autoreleasing) if the compatibility check succeeds. 2385 FromPointee = FromPointee.getUnqualifiedType(); 2386 2387 // The unqualified form of the pointee types must be compatible. 2388 ToPointee = ToPointee.getUnqualifiedType(); 2389 bool IncompatibleObjC; 2390 if (Context.typesAreCompatible(FromPointee, ToPointee)) 2391 FromPointee = ToPointee; 2392 else if (!isObjCPointerConversion(FromPointee, ToPointee, FromPointee, 2393 IncompatibleObjC)) 2394 return false; 2395 2396 /// \brief Construct the type we're converting to, which is a pointer to 2397 /// __autoreleasing pointee. 2398 FromPointee = Context.getQualifiedType(FromPointee, FromQuals); 2399 ConvertedType = Context.getPointerType(FromPointee); 2400 return true; 2401 } 2402 2403 bool Sema::IsBlockPointerConversion(QualType FromType, QualType ToType, 2404 QualType& ConvertedType) { 2405 QualType ToPointeeType; 2406 if (const BlockPointerType *ToBlockPtr = 2407 ToType->getAs<BlockPointerType>()) 2408 ToPointeeType = ToBlockPtr->getPointeeType(); 2409 else 2410 return false; 2411 2412 QualType FromPointeeType; 2413 if (const BlockPointerType *FromBlockPtr = 2414 FromType->getAs<BlockPointerType>()) 2415 FromPointeeType = FromBlockPtr->getPointeeType(); 2416 else 2417 return false; 2418 // We have pointer to blocks, check whether the only 2419 // differences in the argument and result types are in Objective-C 2420 // pointer conversions. If so, we permit the conversion. 2421 2422 const FunctionProtoType *FromFunctionType 2423 = FromPointeeType->getAs<FunctionProtoType>(); 2424 const FunctionProtoType *ToFunctionType 2425 = ToPointeeType->getAs<FunctionProtoType>(); 2426 2427 if (!FromFunctionType || !ToFunctionType) 2428 return false; 2429 2430 if (Context.hasSameType(FromPointeeType, ToPointeeType)) 2431 return true; 2432 2433 // Perform the quick checks that will tell us whether these 2434 // function types are obviously different. 2435 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 2436 FromFunctionType->isVariadic() != ToFunctionType->isVariadic()) 2437 return false; 2438 2439 FunctionType::ExtInfo FromEInfo = FromFunctionType->getExtInfo(); 2440 FunctionType::ExtInfo ToEInfo = ToFunctionType->getExtInfo(); 2441 if (FromEInfo != ToEInfo) 2442 return false; 2443 2444 bool IncompatibleObjC = false; 2445 if (Context.hasSameType(FromFunctionType->getResultType(), 2446 ToFunctionType->getResultType())) { 2447 // Okay, the types match exactly. Nothing to do. 2448 } else { 2449 QualType RHS = FromFunctionType->getResultType(); 2450 QualType LHS = ToFunctionType->getResultType(); 2451 if ((!getLangOpts().CPlusPlus || !RHS->isRecordType()) && 2452 !RHS.hasQualifiers() && LHS.hasQualifiers()) 2453 LHS = LHS.getUnqualifiedType(); 2454 2455 if (Context.hasSameType(RHS,LHS)) { 2456 // OK exact match. 2457 } else if (isObjCPointerConversion(RHS, LHS, 2458 ConvertedType, IncompatibleObjC)) { 2459 if (IncompatibleObjC) 2460 return false; 2461 // Okay, we have an Objective-C pointer conversion. 2462 } 2463 else 2464 return false; 2465 } 2466 2467 // Check argument types. 2468 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 2469 ArgIdx != NumArgs; ++ArgIdx) { 2470 IncompatibleObjC = false; 2471 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 2472 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 2473 if (Context.hasSameType(FromArgType, ToArgType)) { 2474 // Okay, the types match exactly. Nothing to do. 2475 } else if (isObjCPointerConversion(ToArgType, FromArgType, 2476 ConvertedType, IncompatibleObjC)) { 2477 if (IncompatibleObjC) 2478 return false; 2479 // Okay, we have an Objective-C pointer conversion. 2480 } else 2481 // Argument types are too different. Abort. 2482 return false; 2483 } 2484 if (LangOpts.ObjCAutoRefCount && 2485 !Context.FunctionTypesMatchOnNSConsumedAttrs(FromFunctionType, 2486 ToFunctionType)) 2487 return false; 2488 2489 ConvertedType = ToType; 2490 return true; 2491 } 2492 2493 enum { 2494 ft_default, 2495 ft_different_class, 2496 ft_parameter_arity, 2497 ft_parameter_mismatch, 2498 ft_return_type, 2499 ft_qualifer_mismatch 2500 }; 2501 2502 /// HandleFunctionTypeMismatch - Gives diagnostic information for differeing 2503 /// function types. Catches different number of parameter, mismatch in 2504 /// parameter types, and different return types. 2505 void Sema::HandleFunctionTypeMismatch(PartialDiagnostic &PDiag, 2506 QualType FromType, QualType ToType) { 2507 // If either type is not valid, include no extra info. 2508 if (FromType.isNull() || ToType.isNull()) { 2509 PDiag << ft_default; 2510 return; 2511 } 2512 2513 // Get the function type from the pointers. 2514 if (FromType->isMemberPointerType() && ToType->isMemberPointerType()) { 2515 const MemberPointerType *FromMember = FromType->getAs<MemberPointerType>(), 2516 *ToMember = ToType->getAs<MemberPointerType>(); 2517 if (FromMember->getClass() != ToMember->getClass()) { 2518 PDiag << ft_different_class << QualType(ToMember->getClass(), 0) 2519 << QualType(FromMember->getClass(), 0); 2520 return; 2521 } 2522 FromType = FromMember->getPointeeType(); 2523 ToType = ToMember->getPointeeType(); 2524 } 2525 2526 if (FromType->isPointerType()) 2527 FromType = FromType->getPointeeType(); 2528 if (ToType->isPointerType()) 2529 ToType = ToType->getPointeeType(); 2530 2531 // Remove references. 2532 FromType = FromType.getNonReferenceType(); 2533 ToType = ToType.getNonReferenceType(); 2534 2535 // Don't print extra info for non-specialized template functions. 2536 if (FromType->isInstantiationDependentType() && 2537 !FromType->getAs<TemplateSpecializationType>()) { 2538 PDiag << ft_default; 2539 return; 2540 } 2541 2542 // No extra info for same types. 2543 if (Context.hasSameType(FromType, ToType)) { 2544 PDiag << ft_default; 2545 return; 2546 } 2547 2548 const FunctionProtoType *FromFunction = FromType->getAs<FunctionProtoType>(), 2549 *ToFunction = ToType->getAs<FunctionProtoType>(); 2550 2551 // Both types need to be function types. 2552 if (!FromFunction || !ToFunction) { 2553 PDiag << ft_default; 2554 return; 2555 } 2556 2557 if (FromFunction->getNumArgs() != ToFunction->getNumArgs()) { 2558 PDiag << ft_parameter_arity << ToFunction->getNumArgs() 2559 << FromFunction->getNumArgs(); 2560 return; 2561 } 2562 2563 // Handle different parameter types. 2564 unsigned ArgPos; 2565 if (!FunctionArgTypesAreEqual(FromFunction, ToFunction, &ArgPos)) { 2566 PDiag << ft_parameter_mismatch << ArgPos + 1 2567 << ToFunction->getArgType(ArgPos) 2568 << FromFunction->getArgType(ArgPos); 2569 return; 2570 } 2571 2572 // Handle different return type. 2573 if (!Context.hasSameType(FromFunction->getResultType(), 2574 ToFunction->getResultType())) { 2575 PDiag << ft_return_type << ToFunction->getResultType() 2576 << FromFunction->getResultType(); 2577 return; 2578 } 2579 2580 unsigned FromQuals = FromFunction->getTypeQuals(), 2581 ToQuals = ToFunction->getTypeQuals(); 2582 if (FromQuals != ToQuals) { 2583 PDiag << ft_qualifer_mismatch << ToQuals << FromQuals; 2584 return; 2585 } 2586 2587 // Unable to find a difference, so add no extra info. 2588 PDiag << ft_default; 2589 } 2590 2591 /// FunctionArgTypesAreEqual - This routine checks two function proto types 2592 /// for equality of their argument types. Caller has already checked that 2593 /// they have same number of arguments. This routine assumes that Objective-C 2594 /// pointer types which only differ in their protocol qualifiers are equal. 2595 /// If the parameters are different, ArgPos will have the parameter index 2596 /// of the first different parameter. 2597 bool Sema::FunctionArgTypesAreEqual(const FunctionProtoType *OldType, 2598 const FunctionProtoType *NewType, 2599 unsigned *ArgPos) { 2600 if (!getLangOpts().ObjC1) { 2601 for (FunctionProtoType::arg_type_iterator O = OldType->arg_type_begin(), 2602 N = NewType->arg_type_begin(), 2603 E = OldType->arg_type_end(); O && (O != E); ++O, ++N) { 2604 if (!Context.hasSameType(*O, *N)) { 2605 if (ArgPos) *ArgPos = O - OldType->arg_type_begin(); 2606 return false; 2607 } 2608 } 2609 return true; 2610 } 2611 2612 for (FunctionProtoType::arg_type_iterator O = OldType->arg_type_begin(), 2613 N = NewType->arg_type_begin(), 2614 E = OldType->arg_type_end(); O && (O != E); ++O, ++N) { 2615 QualType ToType = (*O); 2616 QualType FromType = (*N); 2617 if (!Context.hasSameType(ToType, FromType)) { 2618 if (const PointerType *PTTo = ToType->getAs<PointerType>()) { 2619 if (const PointerType *PTFr = FromType->getAs<PointerType>()) 2620 if ((PTTo->getPointeeType()->isObjCQualifiedIdType() && 2621 PTFr->getPointeeType()->isObjCQualifiedIdType()) || 2622 (PTTo->getPointeeType()->isObjCQualifiedClassType() && 2623 PTFr->getPointeeType()->isObjCQualifiedClassType())) 2624 continue; 2625 } 2626 else if (const ObjCObjectPointerType *PTTo = 2627 ToType->getAs<ObjCObjectPointerType>()) { 2628 if (const ObjCObjectPointerType *PTFr = 2629 FromType->getAs<ObjCObjectPointerType>()) 2630 if (Context.hasSameUnqualifiedType( 2631 PTTo->getObjectType()->getBaseType(), 2632 PTFr->getObjectType()->getBaseType())) 2633 continue; 2634 } 2635 if (ArgPos) *ArgPos = O - OldType->arg_type_begin(); 2636 return false; 2637 } 2638 } 2639 return true; 2640 } 2641 2642 /// CheckPointerConversion - Check the pointer conversion from the 2643 /// expression From to the type ToType. This routine checks for 2644 /// ambiguous or inaccessible derived-to-base pointer 2645 /// conversions for which IsPointerConversion has already returned 2646 /// true. It returns true and produces a diagnostic if there was an 2647 /// error, or returns false otherwise. 2648 bool Sema::CheckPointerConversion(Expr *From, QualType ToType, 2649 CastKind &Kind, 2650 CXXCastPath& BasePath, 2651 bool IgnoreBaseAccess) { 2652 QualType FromType = From->getType(); 2653 bool IsCStyleOrFunctionalCast = IgnoreBaseAccess; 2654 2655 Kind = CK_BitCast; 2656 2657 if (!IsCStyleOrFunctionalCast && !FromType->isAnyPointerType() && 2658 From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull) == 2659 Expr::NPCK_ZeroExpression) { 2660 if (Context.hasSameUnqualifiedType(From->getType(), Context.BoolTy)) 2661 DiagRuntimeBehavior(From->getExprLoc(), From, 2662 PDiag(diag::warn_impcast_bool_to_null_pointer) 2663 << ToType << From->getSourceRange()); 2664 else if (!isUnevaluatedContext()) 2665 Diag(From->getExprLoc(), diag::warn_non_literal_null_pointer) 2666 << ToType << From->getSourceRange(); 2667 } 2668 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) { 2669 if (const PointerType *FromPtrType = FromType->getAs<PointerType>()) { 2670 QualType FromPointeeType = FromPtrType->getPointeeType(), 2671 ToPointeeType = ToPtrType->getPointeeType(); 2672 2673 if (FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 2674 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) { 2675 // We must have a derived-to-base conversion. Check an 2676 // ambiguous or inaccessible conversion. 2677 if (CheckDerivedToBaseConversion(FromPointeeType, ToPointeeType, 2678 From->getExprLoc(), 2679 From->getSourceRange(), &BasePath, 2680 IgnoreBaseAccess)) 2681 return true; 2682 2683 // The conversion was successful. 2684 Kind = CK_DerivedToBase; 2685 } 2686 } 2687 } else if (const ObjCObjectPointerType *ToPtrType = 2688 ToType->getAs<ObjCObjectPointerType>()) { 2689 if (const ObjCObjectPointerType *FromPtrType = 2690 FromType->getAs<ObjCObjectPointerType>()) { 2691 // Objective-C++ conversions are always okay. 2692 // FIXME: We should have a different class of conversions for the 2693 // Objective-C++ implicit conversions. 2694 if (FromPtrType->isObjCBuiltinType() || ToPtrType->isObjCBuiltinType()) 2695 return false; 2696 } else if (FromType->isBlockPointerType()) { 2697 Kind = CK_BlockPointerToObjCPointerCast; 2698 } else { 2699 Kind = CK_CPointerToObjCPointerCast; 2700 } 2701 } else if (ToType->isBlockPointerType()) { 2702 if (!FromType->isBlockPointerType()) 2703 Kind = CK_AnyPointerToBlockPointerCast; 2704 } 2705 2706 // We shouldn't fall into this case unless it's valid for other 2707 // reasons. 2708 if (From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 2709 Kind = CK_NullToPointer; 2710 2711 return false; 2712 } 2713 2714 /// IsMemberPointerConversion - Determines whether the conversion of the 2715 /// expression From, which has the (possibly adjusted) type FromType, can be 2716 /// converted to the type ToType via a member pointer conversion (C++ 4.11). 2717 /// If so, returns true and places the converted type (that might differ from 2718 /// ToType in its cv-qualifiers at some level) into ConvertedType. 2719 bool Sema::IsMemberPointerConversion(Expr *From, QualType FromType, 2720 QualType ToType, 2721 bool InOverloadResolution, 2722 QualType &ConvertedType) { 2723 const MemberPointerType *ToTypePtr = ToType->getAs<MemberPointerType>(); 2724 if (!ToTypePtr) 2725 return false; 2726 2727 // A null pointer constant can be converted to a member pointer (C++ 4.11p1) 2728 if (From->isNullPointerConstant(Context, 2729 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 2730 : Expr::NPC_ValueDependentIsNull)) { 2731 ConvertedType = ToType; 2732 return true; 2733 } 2734 2735 // Otherwise, both types have to be member pointers. 2736 const MemberPointerType *FromTypePtr = FromType->getAs<MemberPointerType>(); 2737 if (!FromTypePtr) 2738 return false; 2739 2740 // A pointer to member of B can be converted to a pointer to member of D, 2741 // where D is derived from B (C++ 4.11p2). 2742 QualType FromClass(FromTypePtr->getClass(), 0); 2743 QualType ToClass(ToTypePtr->getClass(), 0); 2744 2745 if (!Context.hasSameUnqualifiedType(FromClass, ToClass) && 2746 !RequireCompleteType(From->getLocStart(), ToClass, 0) && 2747 IsDerivedFrom(ToClass, FromClass)) { 2748 ConvertedType = Context.getMemberPointerType(FromTypePtr->getPointeeType(), 2749 ToClass.getTypePtr()); 2750 return true; 2751 } 2752 2753 return false; 2754 } 2755 2756 /// CheckMemberPointerConversion - Check the member pointer conversion from the 2757 /// expression From to the type ToType. This routine checks for ambiguous or 2758 /// virtual or inaccessible base-to-derived member pointer conversions 2759 /// for which IsMemberPointerConversion has already returned true. It returns 2760 /// true and produces a diagnostic if there was an error, or returns false 2761 /// otherwise. 2762 bool Sema::CheckMemberPointerConversion(Expr *From, QualType ToType, 2763 CastKind &Kind, 2764 CXXCastPath &BasePath, 2765 bool IgnoreBaseAccess) { 2766 QualType FromType = From->getType(); 2767 const MemberPointerType *FromPtrType = FromType->getAs<MemberPointerType>(); 2768 if (!FromPtrType) { 2769 // This must be a null pointer to member pointer conversion 2770 assert(From->isNullPointerConstant(Context, 2771 Expr::NPC_ValueDependentIsNull) && 2772 "Expr must be null pointer constant!"); 2773 Kind = CK_NullToMemberPointer; 2774 return false; 2775 } 2776 2777 const MemberPointerType *ToPtrType = ToType->getAs<MemberPointerType>(); 2778 assert(ToPtrType && "No member pointer cast has a target type " 2779 "that is not a member pointer."); 2780 2781 QualType FromClass = QualType(FromPtrType->getClass(), 0); 2782 QualType ToClass = QualType(ToPtrType->getClass(), 0); 2783 2784 // FIXME: What about dependent types? 2785 assert(FromClass->isRecordType() && "Pointer into non-class."); 2786 assert(ToClass->isRecordType() && "Pointer into non-class."); 2787 2788 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 2789 /*DetectVirtual=*/true); 2790 bool DerivationOkay = IsDerivedFrom(ToClass, FromClass, Paths); 2791 assert(DerivationOkay && 2792 "Should not have been called if derivation isn't OK."); 2793 (void)DerivationOkay; 2794 2795 if (Paths.isAmbiguous(Context.getCanonicalType(FromClass). 2796 getUnqualifiedType())) { 2797 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths); 2798 Diag(From->getExprLoc(), diag::err_ambiguous_memptr_conv) 2799 << 0 << FromClass << ToClass << PathDisplayStr << From->getSourceRange(); 2800 return true; 2801 } 2802 2803 if (const RecordType *VBase = Paths.getDetectedVirtual()) { 2804 Diag(From->getExprLoc(), diag::err_memptr_conv_via_virtual) 2805 << FromClass << ToClass << QualType(VBase, 0) 2806 << From->getSourceRange(); 2807 return true; 2808 } 2809 2810 if (!IgnoreBaseAccess) 2811 CheckBaseClassAccess(From->getExprLoc(), FromClass, ToClass, 2812 Paths.front(), 2813 diag::err_downcast_from_inaccessible_base); 2814 2815 // Must be a base to derived member conversion. 2816 BuildBasePathArray(Paths, BasePath); 2817 Kind = CK_BaseToDerivedMemberPointer; 2818 return false; 2819 } 2820 2821 /// IsQualificationConversion - Determines whether the conversion from 2822 /// an rvalue of type FromType to ToType is a qualification conversion 2823 /// (C++ 4.4). 2824 /// 2825 /// \param ObjCLifetimeConversion Output parameter that will be set to indicate 2826 /// when the qualification conversion involves a change in the Objective-C 2827 /// object lifetime. 2828 bool 2829 Sema::IsQualificationConversion(QualType FromType, QualType ToType, 2830 bool CStyle, bool &ObjCLifetimeConversion) { 2831 FromType = Context.getCanonicalType(FromType); 2832 ToType = Context.getCanonicalType(ToType); 2833 ObjCLifetimeConversion = false; 2834 2835 // If FromType and ToType are the same type, this is not a 2836 // qualification conversion. 2837 if (FromType.getUnqualifiedType() == ToType.getUnqualifiedType()) 2838 return false; 2839 2840 // (C++ 4.4p4): 2841 // A conversion can add cv-qualifiers at levels other than the first 2842 // in multi-level pointers, subject to the following rules: [...] 2843 bool PreviousToQualsIncludeConst = true; 2844 bool UnwrappedAnyPointer = false; 2845 while (Context.UnwrapSimilarPointerTypes(FromType, ToType)) { 2846 // Within each iteration of the loop, we check the qualifiers to 2847 // determine if this still looks like a qualification 2848 // conversion. Then, if all is well, we unwrap one more level of 2849 // pointers or pointers-to-members and do it all again 2850 // until there are no more pointers or pointers-to-members left to 2851 // unwrap. 2852 UnwrappedAnyPointer = true; 2853 2854 Qualifiers FromQuals = FromType.getQualifiers(); 2855 Qualifiers ToQuals = ToType.getQualifiers(); 2856 2857 // Objective-C ARC: 2858 // Check Objective-C lifetime conversions. 2859 if (FromQuals.getObjCLifetime() != ToQuals.getObjCLifetime() && 2860 UnwrappedAnyPointer) { 2861 if (ToQuals.compatiblyIncludesObjCLifetime(FromQuals)) { 2862 ObjCLifetimeConversion = true; 2863 FromQuals.removeObjCLifetime(); 2864 ToQuals.removeObjCLifetime(); 2865 } else { 2866 // Qualification conversions cannot cast between different 2867 // Objective-C lifetime qualifiers. 2868 return false; 2869 } 2870 } 2871 2872 // Allow addition/removal of GC attributes but not changing GC attributes. 2873 if (FromQuals.getObjCGCAttr() != ToQuals.getObjCGCAttr() && 2874 (!FromQuals.hasObjCGCAttr() || !ToQuals.hasObjCGCAttr())) { 2875 FromQuals.removeObjCGCAttr(); 2876 ToQuals.removeObjCGCAttr(); 2877 } 2878 2879 // -- for every j > 0, if const is in cv 1,j then const is in cv 2880 // 2,j, and similarly for volatile. 2881 if (!CStyle && !ToQuals.compatiblyIncludes(FromQuals)) 2882 return false; 2883 2884 // -- if the cv 1,j and cv 2,j are different, then const is in 2885 // every cv for 0 < k < j. 2886 if (!CStyle && FromQuals.getCVRQualifiers() != ToQuals.getCVRQualifiers() 2887 && !PreviousToQualsIncludeConst) 2888 return false; 2889 2890 // Keep track of whether all prior cv-qualifiers in the "to" type 2891 // include const. 2892 PreviousToQualsIncludeConst 2893 = PreviousToQualsIncludeConst && ToQuals.hasConst(); 2894 } 2895 2896 // We are left with FromType and ToType being the pointee types 2897 // after unwrapping the original FromType and ToType the same number 2898 // of types. If we unwrapped any pointers, and if FromType and 2899 // ToType have the same unqualified type (since we checked 2900 // qualifiers above), then this is a qualification conversion. 2901 return UnwrappedAnyPointer && Context.hasSameUnqualifiedType(FromType,ToType); 2902 } 2903 2904 /// \brief - Determine whether this is a conversion from a scalar type to an 2905 /// atomic type. 2906 /// 2907 /// If successful, updates \c SCS's second and third steps in the conversion 2908 /// sequence to finish the conversion. 2909 static bool tryAtomicConversion(Sema &S, Expr *From, QualType ToType, 2910 bool InOverloadResolution, 2911 StandardConversionSequence &SCS, 2912 bool CStyle) { 2913 const AtomicType *ToAtomic = ToType->getAs<AtomicType>(); 2914 if (!ToAtomic) 2915 return false; 2916 2917 StandardConversionSequence InnerSCS; 2918 if (!IsStandardConversion(S, From, ToAtomic->getValueType(), 2919 InOverloadResolution, InnerSCS, 2920 CStyle, /*AllowObjCWritebackConversion=*/false)) 2921 return false; 2922 2923 SCS.Second = InnerSCS.Second; 2924 SCS.setToType(1, InnerSCS.getToType(1)); 2925 SCS.Third = InnerSCS.Third; 2926 SCS.QualificationIncludesObjCLifetime 2927 = InnerSCS.QualificationIncludesObjCLifetime; 2928 SCS.setToType(2, InnerSCS.getToType(2)); 2929 return true; 2930 } 2931 2932 static bool isFirstArgumentCompatibleWithType(ASTContext &Context, 2933 CXXConstructorDecl *Constructor, 2934 QualType Type) { 2935 const FunctionProtoType *CtorType = 2936 Constructor->getType()->getAs<FunctionProtoType>(); 2937 if (CtorType->getNumArgs() > 0) { 2938 QualType FirstArg = CtorType->getArgType(0); 2939 if (Context.hasSameUnqualifiedType(Type, FirstArg.getNonReferenceType())) 2940 return true; 2941 } 2942 return false; 2943 } 2944 2945 static OverloadingResult 2946 IsInitializerListConstructorConversion(Sema &S, Expr *From, QualType ToType, 2947 CXXRecordDecl *To, 2948 UserDefinedConversionSequence &User, 2949 OverloadCandidateSet &CandidateSet, 2950 bool AllowExplicit) { 2951 DeclContext::lookup_result R = S.LookupConstructors(To); 2952 for (DeclContext::lookup_iterator Con = R.begin(), ConEnd = R.end(); 2953 Con != ConEnd; ++Con) { 2954 NamedDecl *D = *Con; 2955 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2956 2957 // Find the constructor (which may be a template). 2958 CXXConstructorDecl *Constructor = 0; 2959 FunctionTemplateDecl *ConstructorTmpl 2960 = dyn_cast<FunctionTemplateDecl>(D); 2961 if (ConstructorTmpl) 2962 Constructor 2963 = cast<CXXConstructorDecl>(ConstructorTmpl->getTemplatedDecl()); 2964 else 2965 Constructor = cast<CXXConstructorDecl>(D); 2966 2967 bool Usable = !Constructor->isInvalidDecl() && 2968 S.isInitListConstructor(Constructor) && 2969 (AllowExplicit || !Constructor->isExplicit()); 2970 if (Usable) { 2971 // If the first argument is (a reference to) the target type, 2972 // suppress conversions. 2973 bool SuppressUserConversions = 2974 isFirstArgumentCompatibleWithType(S.Context, Constructor, ToType); 2975 if (ConstructorTmpl) 2976 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2977 /*ExplicitArgs*/ 0, 2978 From, CandidateSet, 2979 SuppressUserConversions); 2980 else 2981 S.AddOverloadCandidate(Constructor, FoundDecl, 2982 From, CandidateSet, 2983 SuppressUserConversions); 2984 } 2985 } 2986 2987 bool HadMultipleCandidates = (CandidateSet.size() > 1); 2988 2989 OverloadCandidateSet::iterator Best; 2990 switch (CandidateSet.BestViableFunction(S, From->getLocStart(), Best, true)) { 2991 case OR_Success: { 2992 // Record the standard conversion we used and the conversion function. 2993 CXXConstructorDecl *Constructor = cast<CXXConstructorDecl>(Best->Function); 2994 QualType ThisType = Constructor->getThisType(S.Context); 2995 // Initializer lists don't have conversions as such. 2996 User.Before.setAsIdentityConversion(); 2997 User.HadMultipleCandidates = HadMultipleCandidates; 2998 User.ConversionFunction = Constructor; 2999 User.FoundConversionFunction = Best->FoundDecl; 3000 User.After.setAsIdentityConversion(); 3001 User.After.setFromType(ThisType->getAs<PointerType>()->getPointeeType()); 3002 User.After.setAllToTypes(ToType); 3003 return OR_Success; 3004 } 3005 3006 case OR_No_Viable_Function: 3007 return OR_No_Viable_Function; 3008 case OR_Deleted: 3009 return OR_Deleted; 3010 case OR_Ambiguous: 3011 return OR_Ambiguous; 3012 } 3013 3014 llvm_unreachable("Invalid OverloadResult!"); 3015 } 3016 3017 /// Determines whether there is a user-defined conversion sequence 3018 /// (C++ [over.ics.user]) that converts expression From to the type 3019 /// ToType. If such a conversion exists, User will contain the 3020 /// user-defined conversion sequence that performs such a conversion 3021 /// and this routine will return true. Otherwise, this routine returns 3022 /// false and User is unspecified. 3023 /// 3024 /// \param AllowExplicit true if the conversion should consider C++0x 3025 /// "explicit" conversion functions as well as non-explicit conversion 3026 /// functions (C++0x [class.conv.fct]p2). 3027 static OverloadingResult 3028 IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 3029 UserDefinedConversionSequence &User, 3030 OverloadCandidateSet &CandidateSet, 3031 bool AllowExplicit) { 3032 // Whether we will only visit constructors. 3033 bool ConstructorsOnly = false; 3034 3035 // If the type we are conversion to is a class type, enumerate its 3036 // constructors. 3037 if (const RecordType *ToRecordType = ToType->getAs<RecordType>()) { 3038 // C++ [over.match.ctor]p1: 3039 // When objects of class type are direct-initialized (8.5), or 3040 // copy-initialized from an expression of the same or a 3041 // derived class type (8.5), overload resolution selects the 3042 // constructor. [...] For copy-initialization, the candidate 3043 // functions are all the converting constructors (12.3.1) of 3044 // that class. The argument list is the expression-list within 3045 // the parentheses of the initializer. 3046 if (S.Context.hasSameUnqualifiedType(ToType, From->getType()) || 3047 (From->getType()->getAs<RecordType>() && 3048 S.IsDerivedFrom(From->getType(), ToType))) 3049 ConstructorsOnly = true; 3050 3051 S.RequireCompleteType(From->getExprLoc(), ToType, 0); 3052 // RequireCompleteType may have returned true due to some invalid decl 3053 // during template instantiation, but ToType may be complete enough now 3054 // to try to recover. 3055 if (ToType->isIncompleteType()) { 3056 // We're not going to find any constructors. 3057 } else if (CXXRecordDecl *ToRecordDecl 3058 = dyn_cast<CXXRecordDecl>(ToRecordType->getDecl())) { 3059 3060 Expr **Args = &From; 3061 unsigned NumArgs = 1; 3062 bool ListInitializing = false; 3063 if (InitListExpr *InitList = dyn_cast<InitListExpr>(From)) { 3064 // But first, see if there is an init-list-contructor that will work. 3065 OverloadingResult Result = IsInitializerListConstructorConversion( 3066 S, From, ToType, ToRecordDecl, User, CandidateSet, AllowExplicit); 3067 if (Result != OR_No_Viable_Function) 3068 return Result; 3069 // Never mind. 3070 CandidateSet.clear(); 3071 3072 // If we're list-initializing, we pass the individual elements as 3073 // arguments, not the entire list. 3074 Args = InitList->getInits(); 3075 NumArgs = InitList->getNumInits(); 3076 ListInitializing = true; 3077 } 3078 3079 DeclContext::lookup_result R = S.LookupConstructors(ToRecordDecl); 3080 for (DeclContext::lookup_iterator Con = R.begin(), ConEnd = R.end(); 3081 Con != ConEnd; ++Con) { 3082 NamedDecl *D = *Con; 3083 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 3084 3085 // Find the constructor (which may be a template). 3086 CXXConstructorDecl *Constructor = 0; 3087 FunctionTemplateDecl *ConstructorTmpl 3088 = dyn_cast<FunctionTemplateDecl>(D); 3089 if (ConstructorTmpl) 3090 Constructor 3091 = cast<CXXConstructorDecl>(ConstructorTmpl->getTemplatedDecl()); 3092 else 3093 Constructor = cast<CXXConstructorDecl>(D); 3094 3095 bool Usable = !Constructor->isInvalidDecl(); 3096 if (ListInitializing) 3097 Usable = Usable && (AllowExplicit || !Constructor->isExplicit()); 3098 else 3099 Usable = Usable &&Constructor->isConvertingConstructor(AllowExplicit); 3100 if (Usable) { 3101 bool SuppressUserConversions = !ConstructorsOnly; 3102 if (SuppressUserConversions && ListInitializing) { 3103 SuppressUserConversions = false; 3104 if (NumArgs == 1) { 3105 // If the first argument is (a reference to) the target type, 3106 // suppress conversions. 3107 SuppressUserConversions = isFirstArgumentCompatibleWithType( 3108 S.Context, Constructor, ToType); 3109 } 3110 } 3111 if (ConstructorTmpl) 3112 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 3113 /*ExplicitArgs*/ 0, 3114 llvm::makeArrayRef(Args, NumArgs), 3115 CandidateSet, SuppressUserConversions); 3116 else 3117 // Allow one user-defined conversion when user specifies a 3118 // From->ToType conversion via an static cast (c-style, etc). 3119 S.AddOverloadCandidate(Constructor, FoundDecl, 3120 llvm::makeArrayRef(Args, NumArgs), 3121 CandidateSet, SuppressUserConversions); 3122 } 3123 } 3124 } 3125 } 3126 3127 // Enumerate conversion functions, if we're allowed to. 3128 if (ConstructorsOnly || isa<InitListExpr>(From)) { 3129 } else if (S.RequireCompleteType(From->getLocStart(), From->getType(), 0)) { 3130 // No conversion functions from incomplete types. 3131 } else if (const RecordType *FromRecordType 3132 = From->getType()->getAs<RecordType>()) { 3133 if (CXXRecordDecl *FromRecordDecl 3134 = dyn_cast<CXXRecordDecl>(FromRecordType->getDecl())) { 3135 // Add all of the conversion functions as candidates. 3136 std::pair<CXXRecordDecl::conversion_iterator, 3137 CXXRecordDecl::conversion_iterator> 3138 Conversions = FromRecordDecl->getVisibleConversionFunctions(); 3139 for (CXXRecordDecl::conversion_iterator 3140 I = Conversions.first, E = Conversions.second; I != E; ++I) { 3141 DeclAccessPair FoundDecl = I.getPair(); 3142 NamedDecl *D = FoundDecl.getDecl(); 3143 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 3144 if (isa<UsingShadowDecl>(D)) 3145 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 3146 3147 CXXConversionDecl *Conv; 3148 FunctionTemplateDecl *ConvTemplate; 3149 if ((ConvTemplate = dyn_cast<FunctionTemplateDecl>(D))) 3150 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 3151 else 3152 Conv = cast<CXXConversionDecl>(D); 3153 3154 if (AllowExplicit || !Conv->isExplicit()) { 3155 if (ConvTemplate) 3156 S.AddTemplateConversionCandidate(ConvTemplate, FoundDecl, 3157 ActingContext, From, ToType, 3158 CandidateSet); 3159 else 3160 S.AddConversionCandidate(Conv, FoundDecl, ActingContext, 3161 From, ToType, CandidateSet); 3162 } 3163 } 3164 } 3165 } 3166 3167 bool HadMultipleCandidates = (CandidateSet.size() > 1); 3168 3169 OverloadCandidateSet::iterator Best; 3170 switch (CandidateSet.BestViableFunction(S, From->getLocStart(), Best, true)) { 3171 case OR_Success: 3172 // Record the standard conversion we used and the conversion function. 3173 if (CXXConstructorDecl *Constructor 3174 = dyn_cast<CXXConstructorDecl>(Best->Function)) { 3175 // C++ [over.ics.user]p1: 3176 // If the user-defined conversion is specified by a 3177 // constructor (12.3.1), the initial standard conversion 3178 // sequence converts the source type to the type required by 3179 // the argument of the constructor. 3180 // 3181 QualType ThisType = Constructor->getThisType(S.Context); 3182 if (isa<InitListExpr>(From)) { 3183 // Initializer lists don't have conversions as such. 3184 User.Before.setAsIdentityConversion(); 3185 } else { 3186 if (Best->Conversions[0].isEllipsis()) 3187 User.EllipsisConversion = true; 3188 else { 3189 User.Before = Best->Conversions[0].Standard; 3190 User.EllipsisConversion = false; 3191 } 3192 } 3193 User.HadMultipleCandidates = HadMultipleCandidates; 3194 User.ConversionFunction = Constructor; 3195 User.FoundConversionFunction = Best->FoundDecl; 3196 User.After.setAsIdentityConversion(); 3197 User.After.setFromType(ThisType->getAs<PointerType>()->getPointeeType()); 3198 User.After.setAllToTypes(ToType); 3199 return OR_Success; 3200 } 3201 if (CXXConversionDecl *Conversion 3202 = dyn_cast<CXXConversionDecl>(Best->Function)) { 3203 // C++ [over.ics.user]p1: 3204 // 3205 // [...] If the user-defined conversion is specified by a 3206 // conversion function (12.3.2), the initial standard 3207 // conversion sequence converts the source type to the 3208 // implicit object parameter of the conversion function. 3209 User.Before = Best->Conversions[0].Standard; 3210 User.HadMultipleCandidates = HadMultipleCandidates; 3211 User.ConversionFunction = Conversion; 3212 User.FoundConversionFunction = Best->FoundDecl; 3213 User.EllipsisConversion = false; 3214 3215 // C++ [over.ics.user]p2: 3216 // The second standard conversion sequence converts the 3217 // result of the user-defined conversion to the target type 3218 // for the sequence. Since an implicit conversion sequence 3219 // is an initialization, the special rules for 3220 // initialization by user-defined conversion apply when 3221 // selecting the best user-defined conversion for a 3222 // user-defined conversion sequence (see 13.3.3 and 3223 // 13.3.3.1). 3224 User.After = Best->FinalConversion; 3225 return OR_Success; 3226 } 3227 llvm_unreachable("Not a constructor or conversion function?"); 3228 3229 case OR_No_Viable_Function: 3230 return OR_No_Viable_Function; 3231 case OR_Deleted: 3232 // No conversion here! We're done. 3233 return OR_Deleted; 3234 3235 case OR_Ambiguous: 3236 return OR_Ambiguous; 3237 } 3238 3239 llvm_unreachable("Invalid OverloadResult!"); 3240 } 3241 3242 bool 3243 Sema::DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType) { 3244 ImplicitConversionSequence ICS; 3245 OverloadCandidateSet CandidateSet(From->getExprLoc()); 3246 OverloadingResult OvResult = 3247 IsUserDefinedConversion(*this, From, ToType, ICS.UserDefined, 3248 CandidateSet, false); 3249 if (OvResult == OR_Ambiguous) 3250 Diag(From->getLocStart(), 3251 diag::err_typecheck_ambiguous_condition) 3252 << From->getType() << ToType << From->getSourceRange(); 3253 else if (OvResult == OR_No_Viable_Function && !CandidateSet.empty()) 3254 Diag(From->getLocStart(), 3255 diag::err_typecheck_nonviable_condition) 3256 << From->getType() << ToType << From->getSourceRange(); 3257 else 3258 return false; 3259 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, From); 3260 return true; 3261 } 3262 3263 /// \brief Compare the user-defined conversion functions or constructors 3264 /// of two user-defined conversion sequences to determine whether any ordering 3265 /// is possible. 3266 static ImplicitConversionSequence::CompareKind 3267 compareConversionFunctions(Sema &S, 3268 FunctionDecl *Function1, 3269 FunctionDecl *Function2) { 3270 if (!S.getLangOpts().ObjC1 || !S.getLangOpts().CPlusPlus11) 3271 return ImplicitConversionSequence::Indistinguishable; 3272 3273 // Objective-C++: 3274 // If both conversion functions are implicitly-declared conversions from 3275 // a lambda closure type to a function pointer and a block pointer, 3276 // respectively, always prefer the conversion to a function pointer, 3277 // because the function pointer is more lightweight and is more likely 3278 // to keep code working. 3279 CXXConversionDecl *Conv1 = dyn_cast<CXXConversionDecl>(Function1); 3280 if (!Conv1) 3281 return ImplicitConversionSequence::Indistinguishable; 3282 3283 CXXConversionDecl *Conv2 = dyn_cast<CXXConversionDecl>(Function2); 3284 if (!Conv2) 3285 return ImplicitConversionSequence::Indistinguishable; 3286 3287 if (Conv1->getParent()->isLambda() && Conv2->getParent()->isLambda()) { 3288 bool Block1 = Conv1->getConversionType()->isBlockPointerType(); 3289 bool Block2 = Conv2->getConversionType()->isBlockPointerType(); 3290 if (Block1 != Block2) 3291 return Block1? ImplicitConversionSequence::Worse 3292 : ImplicitConversionSequence::Better; 3293 } 3294 3295 return ImplicitConversionSequence::Indistinguishable; 3296 } 3297 3298 /// CompareImplicitConversionSequences - Compare two implicit 3299 /// conversion sequences to determine whether one is better than the 3300 /// other or if they are indistinguishable (C++ 13.3.3.2). 3301 static ImplicitConversionSequence::CompareKind 3302 CompareImplicitConversionSequences(Sema &S, 3303 const ImplicitConversionSequence& ICS1, 3304 const ImplicitConversionSequence& ICS2) 3305 { 3306 // (C++ 13.3.3.2p2): When comparing the basic forms of implicit 3307 // conversion sequences (as defined in 13.3.3.1) 3308 // -- a standard conversion sequence (13.3.3.1.1) is a better 3309 // conversion sequence than a user-defined conversion sequence or 3310 // an ellipsis conversion sequence, and 3311 // -- a user-defined conversion sequence (13.3.3.1.2) is a better 3312 // conversion sequence than an ellipsis conversion sequence 3313 // (13.3.3.1.3). 3314 // 3315 // C++0x [over.best.ics]p10: 3316 // For the purpose of ranking implicit conversion sequences as 3317 // described in 13.3.3.2, the ambiguous conversion sequence is 3318 // treated as a user-defined sequence that is indistinguishable 3319 // from any other user-defined conversion sequence. 3320 if (ICS1.getKindRank() < ICS2.getKindRank()) 3321 return ImplicitConversionSequence::Better; 3322 if (ICS2.getKindRank() < ICS1.getKindRank()) 3323 return ImplicitConversionSequence::Worse; 3324 3325 // The following checks require both conversion sequences to be of 3326 // the same kind. 3327 if (ICS1.getKind() != ICS2.getKind()) 3328 return ImplicitConversionSequence::Indistinguishable; 3329 3330 ImplicitConversionSequence::CompareKind Result = 3331 ImplicitConversionSequence::Indistinguishable; 3332 3333 // Two implicit conversion sequences of the same form are 3334 // indistinguishable conversion sequences unless one of the 3335 // following rules apply: (C++ 13.3.3.2p3): 3336 if (ICS1.isStandard()) 3337 Result = CompareStandardConversionSequences(S, 3338 ICS1.Standard, ICS2.Standard); 3339 else if (ICS1.isUserDefined()) { 3340 // User-defined conversion sequence U1 is a better conversion 3341 // sequence than another user-defined conversion sequence U2 if 3342 // they contain the same user-defined conversion function or 3343 // constructor and if the second standard conversion sequence of 3344 // U1 is better than the second standard conversion sequence of 3345 // U2 (C++ 13.3.3.2p3). 3346 if (ICS1.UserDefined.ConversionFunction == 3347 ICS2.UserDefined.ConversionFunction) 3348 Result = CompareStandardConversionSequences(S, 3349 ICS1.UserDefined.After, 3350 ICS2.UserDefined.After); 3351 else 3352 Result = compareConversionFunctions(S, 3353 ICS1.UserDefined.ConversionFunction, 3354 ICS2.UserDefined.ConversionFunction); 3355 } 3356 3357 // List-initialization sequence L1 is a better conversion sequence than 3358 // list-initialization sequence L2 if L1 converts to std::initializer_list<X> 3359 // for some X and L2 does not. 3360 if (Result == ImplicitConversionSequence::Indistinguishable && 3361 !ICS1.isBad() && 3362 ICS1.isListInitializationSequence() && 3363 ICS2.isListInitializationSequence()) { 3364 if (ICS1.isStdInitializerListElement() && 3365 !ICS2.isStdInitializerListElement()) 3366 return ImplicitConversionSequence::Better; 3367 if (!ICS1.isStdInitializerListElement() && 3368 ICS2.isStdInitializerListElement()) 3369 return ImplicitConversionSequence::Worse; 3370 } 3371 3372 return Result; 3373 } 3374 3375 static bool hasSimilarType(ASTContext &Context, QualType T1, QualType T2) { 3376 while (Context.UnwrapSimilarPointerTypes(T1, T2)) { 3377 Qualifiers Quals; 3378 T1 = Context.getUnqualifiedArrayType(T1, Quals); 3379 T2 = Context.getUnqualifiedArrayType(T2, Quals); 3380 } 3381 3382 return Context.hasSameUnqualifiedType(T1, T2); 3383 } 3384 3385 // Per 13.3.3.2p3, compare the given standard conversion sequences to 3386 // determine if one is a proper subset of the other. 3387 static ImplicitConversionSequence::CompareKind 3388 compareStandardConversionSubsets(ASTContext &Context, 3389 const StandardConversionSequence& SCS1, 3390 const StandardConversionSequence& SCS2) { 3391 ImplicitConversionSequence::CompareKind Result 3392 = ImplicitConversionSequence::Indistinguishable; 3393 3394 // the identity conversion sequence is considered to be a subsequence of 3395 // any non-identity conversion sequence 3396 if (SCS1.isIdentityConversion() && !SCS2.isIdentityConversion()) 3397 return ImplicitConversionSequence::Better; 3398 else if (!SCS1.isIdentityConversion() && SCS2.isIdentityConversion()) 3399 return ImplicitConversionSequence::Worse; 3400 3401 if (SCS1.Second != SCS2.Second) { 3402 if (SCS1.Second == ICK_Identity) 3403 Result = ImplicitConversionSequence::Better; 3404 else if (SCS2.Second == ICK_Identity) 3405 Result = ImplicitConversionSequence::Worse; 3406 else 3407 return ImplicitConversionSequence::Indistinguishable; 3408 } else if (!hasSimilarType(Context, SCS1.getToType(1), SCS2.getToType(1))) 3409 return ImplicitConversionSequence::Indistinguishable; 3410 3411 if (SCS1.Third == SCS2.Third) { 3412 return Context.hasSameType(SCS1.getToType(2), SCS2.getToType(2))? Result 3413 : ImplicitConversionSequence::Indistinguishable; 3414 } 3415 3416 if (SCS1.Third == ICK_Identity) 3417 return Result == ImplicitConversionSequence::Worse 3418 ? ImplicitConversionSequence::Indistinguishable 3419 : ImplicitConversionSequence::Better; 3420 3421 if (SCS2.Third == ICK_Identity) 3422 return Result == ImplicitConversionSequence::Better 3423 ? ImplicitConversionSequence::Indistinguishable 3424 : ImplicitConversionSequence::Worse; 3425 3426 return ImplicitConversionSequence::Indistinguishable; 3427 } 3428 3429 /// \brief Determine whether one of the given reference bindings is better 3430 /// than the other based on what kind of bindings they are. 3431 static bool isBetterReferenceBindingKind(const StandardConversionSequence &SCS1, 3432 const StandardConversionSequence &SCS2) { 3433 // C++0x [over.ics.rank]p3b4: 3434 // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an 3435 // implicit object parameter of a non-static member function declared 3436 // without a ref-qualifier, and *either* S1 binds an rvalue reference 3437 // to an rvalue and S2 binds an lvalue reference *or S1 binds an 3438 // lvalue reference to a function lvalue and S2 binds an rvalue 3439 // reference*. 3440 // 3441 // FIXME: Rvalue references. We're going rogue with the above edits, 3442 // because the semantics in the current C++0x working paper (N3225 at the 3443 // time of this writing) break the standard definition of std::forward 3444 // and std::reference_wrapper when dealing with references to functions. 3445 // Proposed wording changes submitted to CWG for consideration. 3446 if (SCS1.BindsImplicitObjectArgumentWithoutRefQualifier || 3447 SCS2.BindsImplicitObjectArgumentWithoutRefQualifier) 3448 return false; 3449 3450 return (!SCS1.IsLvalueReference && SCS1.BindsToRvalue && 3451 SCS2.IsLvalueReference) || 3452 (SCS1.IsLvalueReference && SCS1.BindsToFunctionLvalue && 3453 !SCS2.IsLvalueReference); 3454 } 3455 3456 /// CompareStandardConversionSequences - Compare two standard 3457 /// conversion sequences to determine whether one is better than the 3458 /// other or if they are indistinguishable (C++ 13.3.3.2p3). 3459 static ImplicitConversionSequence::CompareKind 3460 CompareStandardConversionSequences(Sema &S, 3461 const StandardConversionSequence& SCS1, 3462 const StandardConversionSequence& SCS2) 3463 { 3464 // Standard conversion sequence S1 is a better conversion sequence 3465 // than standard conversion sequence S2 if (C++ 13.3.3.2p3): 3466 3467 // -- S1 is a proper subsequence of S2 (comparing the conversion 3468 // sequences in the canonical form defined by 13.3.3.1.1, 3469 // excluding any Lvalue Transformation; the identity conversion 3470 // sequence is considered to be a subsequence of any 3471 // non-identity conversion sequence) or, if not that, 3472 if (ImplicitConversionSequence::CompareKind CK 3473 = compareStandardConversionSubsets(S.Context, SCS1, SCS2)) 3474 return CK; 3475 3476 // -- the rank of S1 is better than the rank of S2 (by the rules 3477 // defined below), or, if not that, 3478 ImplicitConversionRank Rank1 = SCS1.getRank(); 3479 ImplicitConversionRank Rank2 = SCS2.getRank(); 3480 if (Rank1 < Rank2) 3481 return ImplicitConversionSequence::Better; 3482 else if (Rank2 < Rank1) 3483 return ImplicitConversionSequence::Worse; 3484 3485 // (C++ 13.3.3.2p4): Two conversion sequences with the same rank 3486 // are indistinguishable unless one of the following rules 3487 // applies: 3488 3489 // A conversion that is not a conversion of a pointer, or 3490 // pointer to member, to bool is better than another conversion 3491 // that is such a conversion. 3492 if (SCS1.isPointerConversionToBool() != SCS2.isPointerConversionToBool()) 3493 return SCS2.isPointerConversionToBool() 3494 ? ImplicitConversionSequence::Better 3495 : ImplicitConversionSequence::Worse; 3496 3497 // C++ [over.ics.rank]p4b2: 3498 // 3499 // If class B is derived directly or indirectly from class A, 3500 // conversion of B* to A* is better than conversion of B* to 3501 // void*, and conversion of A* to void* is better than conversion 3502 // of B* to void*. 3503 bool SCS1ConvertsToVoid 3504 = SCS1.isPointerConversionToVoidPointer(S.Context); 3505 bool SCS2ConvertsToVoid 3506 = SCS2.isPointerConversionToVoidPointer(S.Context); 3507 if (SCS1ConvertsToVoid != SCS2ConvertsToVoid) { 3508 // Exactly one of the conversion sequences is a conversion to 3509 // a void pointer; it's the worse conversion. 3510 return SCS2ConvertsToVoid ? ImplicitConversionSequence::Better 3511 : ImplicitConversionSequence::Worse; 3512 } else if (!SCS1ConvertsToVoid && !SCS2ConvertsToVoid) { 3513 // Neither conversion sequence converts to a void pointer; compare 3514 // their derived-to-base conversions. 3515 if (ImplicitConversionSequence::CompareKind DerivedCK 3516 = CompareDerivedToBaseConversions(S, SCS1, SCS2)) 3517 return DerivedCK; 3518 } else if (SCS1ConvertsToVoid && SCS2ConvertsToVoid && 3519 !S.Context.hasSameType(SCS1.getFromType(), SCS2.getFromType())) { 3520 // Both conversion sequences are conversions to void 3521 // pointers. Compare the source types to determine if there's an 3522 // inheritance relationship in their sources. 3523 QualType FromType1 = SCS1.getFromType(); 3524 QualType FromType2 = SCS2.getFromType(); 3525 3526 // Adjust the types we're converting from via the array-to-pointer 3527 // conversion, if we need to. 3528 if (SCS1.First == ICK_Array_To_Pointer) 3529 FromType1 = S.Context.getArrayDecayedType(FromType1); 3530 if (SCS2.First == ICK_Array_To_Pointer) 3531 FromType2 = S.Context.getArrayDecayedType(FromType2); 3532 3533 QualType FromPointee1 = FromType1->getPointeeType().getUnqualifiedType(); 3534 QualType FromPointee2 = FromType2->getPointeeType().getUnqualifiedType(); 3535 3536 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 3537 return ImplicitConversionSequence::Better; 3538 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 3539 return ImplicitConversionSequence::Worse; 3540 3541 // Objective-C++: If one interface is more specific than the 3542 // other, it is the better one. 3543 const ObjCObjectPointerType* FromObjCPtr1 3544 = FromType1->getAs<ObjCObjectPointerType>(); 3545 const ObjCObjectPointerType* FromObjCPtr2 3546 = FromType2->getAs<ObjCObjectPointerType>(); 3547 if (FromObjCPtr1 && FromObjCPtr2) { 3548 bool AssignLeft = S.Context.canAssignObjCInterfaces(FromObjCPtr1, 3549 FromObjCPtr2); 3550 bool AssignRight = S.Context.canAssignObjCInterfaces(FromObjCPtr2, 3551 FromObjCPtr1); 3552 if (AssignLeft != AssignRight) { 3553 return AssignLeft? ImplicitConversionSequence::Better 3554 : ImplicitConversionSequence::Worse; 3555 } 3556 } 3557 } 3558 3559 // Compare based on qualification conversions (C++ 13.3.3.2p3, 3560 // bullet 3). 3561 if (ImplicitConversionSequence::CompareKind QualCK 3562 = CompareQualificationConversions(S, SCS1, SCS2)) 3563 return QualCK; 3564 3565 if (SCS1.ReferenceBinding && SCS2.ReferenceBinding) { 3566 // Check for a better reference binding based on the kind of bindings. 3567 if (isBetterReferenceBindingKind(SCS1, SCS2)) 3568 return ImplicitConversionSequence::Better; 3569 else if (isBetterReferenceBindingKind(SCS2, SCS1)) 3570 return ImplicitConversionSequence::Worse; 3571 3572 // C++ [over.ics.rank]p3b4: 3573 // -- S1 and S2 are reference bindings (8.5.3), and the types to 3574 // which the references refer are the same type except for 3575 // top-level cv-qualifiers, and the type to which the reference 3576 // initialized by S2 refers is more cv-qualified than the type 3577 // to which the reference initialized by S1 refers. 3578 QualType T1 = SCS1.getToType(2); 3579 QualType T2 = SCS2.getToType(2); 3580 T1 = S.Context.getCanonicalType(T1); 3581 T2 = S.Context.getCanonicalType(T2); 3582 Qualifiers T1Quals, T2Quals; 3583 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 3584 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 3585 if (UnqualT1 == UnqualT2) { 3586 // Objective-C++ ARC: If the references refer to objects with different 3587 // lifetimes, prefer bindings that don't change lifetime. 3588 if (SCS1.ObjCLifetimeConversionBinding != 3589 SCS2.ObjCLifetimeConversionBinding) { 3590 return SCS1.ObjCLifetimeConversionBinding 3591 ? ImplicitConversionSequence::Worse 3592 : ImplicitConversionSequence::Better; 3593 } 3594 3595 // If the type is an array type, promote the element qualifiers to the 3596 // type for comparison. 3597 if (isa<ArrayType>(T1) && T1Quals) 3598 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 3599 if (isa<ArrayType>(T2) && T2Quals) 3600 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 3601 if (T2.isMoreQualifiedThan(T1)) 3602 return ImplicitConversionSequence::Better; 3603 else if (T1.isMoreQualifiedThan(T2)) 3604 return ImplicitConversionSequence::Worse; 3605 } 3606 } 3607 3608 // In Microsoft mode, prefer an integral conversion to a 3609 // floating-to-integral conversion if the integral conversion 3610 // is between types of the same size. 3611 // For example: 3612 // void f(float); 3613 // void f(int); 3614 // int main { 3615 // long a; 3616 // f(a); 3617 // } 3618 // Here, MSVC will call f(int) instead of generating a compile error 3619 // as clang will do in standard mode. 3620 if (S.getLangOpts().MicrosoftMode && 3621 SCS1.Second == ICK_Integral_Conversion && 3622 SCS2.Second == ICK_Floating_Integral && 3623 S.Context.getTypeSize(SCS1.getFromType()) == 3624 S.Context.getTypeSize(SCS1.getToType(2))) 3625 return ImplicitConversionSequence::Better; 3626 3627 return ImplicitConversionSequence::Indistinguishable; 3628 } 3629 3630 /// CompareQualificationConversions - Compares two standard conversion 3631 /// sequences to determine whether they can be ranked based on their 3632 /// qualification conversions (C++ 13.3.3.2p3 bullet 3). 3633 ImplicitConversionSequence::CompareKind 3634 CompareQualificationConversions(Sema &S, 3635 const StandardConversionSequence& SCS1, 3636 const StandardConversionSequence& SCS2) { 3637 // C++ 13.3.3.2p3: 3638 // -- S1 and S2 differ only in their qualification conversion and 3639 // yield similar types T1 and T2 (C++ 4.4), respectively, and the 3640 // cv-qualification signature of type T1 is a proper subset of 3641 // the cv-qualification signature of type T2, and S1 is not the 3642 // deprecated string literal array-to-pointer conversion (4.2). 3643 if (SCS1.First != SCS2.First || SCS1.Second != SCS2.Second || 3644 SCS1.Third != SCS2.Third || SCS1.Third != ICK_Qualification) 3645 return ImplicitConversionSequence::Indistinguishable; 3646 3647 // FIXME: the example in the standard doesn't use a qualification 3648 // conversion (!) 3649 QualType T1 = SCS1.getToType(2); 3650 QualType T2 = SCS2.getToType(2); 3651 T1 = S.Context.getCanonicalType(T1); 3652 T2 = S.Context.getCanonicalType(T2); 3653 Qualifiers T1Quals, T2Quals; 3654 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 3655 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 3656 3657 // If the types are the same, we won't learn anything by unwrapped 3658 // them. 3659 if (UnqualT1 == UnqualT2) 3660 return ImplicitConversionSequence::Indistinguishable; 3661 3662 // If the type is an array type, promote the element qualifiers to the type 3663 // for comparison. 3664 if (isa<ArrayType>(T1) && T1Quals) 3665 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 3666 if (isa<ArrayType>(T2) && T2Quals) 3667 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 3668 3669 ImplicitConversionSequence::CompareKind Result 3670 = ImplicitConversionSequence::Indistinguishable; 3671 3672 // Objective-C++ ARC: 3673 // Prefer qualification conversions not involving a change in lifetime 3674 // to qualification conversions that do not change lifetime. 3675 if (SCS1.QualificationIncludesObjCLifetime != 3676 SCS2.QualificationIncludesObjCLifetime) { 3677 Result = SCS1.QualificationIncludesObjCLifetime 3678 ? ImplicitConversionSequence::Worse 3679 : ImplicitConversionSequence::Better; 3680 } 3681 3682 while (S.Context.UnwrapSimilarPointerTypes(T1, T2)) { 3683 // Within each iteration of the loop, we check the qualifiers to 3684 // determine if this still looks like a qualification 3685 // conversion. Then, if all is well, we unwrap one more level of 3686 // pointers or pointers-to-members and do it all again 3687 // until there are no more pointers or pointers-to-members left 3688 // to unwrap. This essentially mimics what 3689 // IsQualificationConversion does, but here we're checking for a 3690 // strict subset of qualifiers. 3691 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 3692 // The qualifiers are the same, so this doesn't tell us anything 3693 // about how the sequences rank. 3694 ; 3695 else if (T2.isMoreQualifiedThan(T1)) { 3696 // T1 has fewer qualifiers, so it could be the better sequence. 3697 if (Result == ImplicitConversionSequence::Worse) 3698 // Neither has qualifiers that are a subset of the other's 3699 // qualifiers. 3700 return ImplicitConversionSequence::Indistinguishable; 3701 3702 Result = ImplicitConversionSequence::Better; 3703 } else if (T1.isMoreQualifiedThan(T2)) { 3704 // T2 has fewer qualifiers, so it could be the better sequence. 3705 if (Result == ImplicitConversionSequence::Better) 3706 // Neither has qualifiers that are a subset of the other's 3707 // qualifiers. 3708 return ImplicitConversionSequence::Indistinguishable; 3709 3710 Result = ImplicitConversionSequence::Worse; 3711 } else { 3712 // Qualifiers are disjoint. 3713 return ImplicitConversionSequence::Indistinguishable; 3714 } 3715 3716 // If the types after this point are equivalent, we're done. 3717 if (S.Context.hasSameUnqualifiedType(T1, T2)) 3718 break; 3719 } 3720 3721 // Check that the winning standard conversion sequence isn't using 3722 // the deprecated string literal array to pointer conversion. 3723 switch (Result) { 3724 case ImplicitConversionSequence::Better: 3725 if (SCS1.DeprecatedStringLiteralToCharPtr) 3726 Result = ImplicitConversionSequence::Indistinguishable; 3727 break; 3728 3729 case ImplicitConversionSequence::Indistinguishable: 3730 break; 3731 3732 case ImplicitConversionSequence::Worse: 3733 if (SCS2.DeprecatedStringLiteralToCharPtr) 3734 Result = ImplicitConversionSequence::Indistinguishable; 3735 break; 3736 } 3737 3738 return Result; 3739 } 3740 3741 /// CompareDerivedToBaseConversions - Compares two standard conversion 3742 /// sequences to determine whether they can be ranked based on their 3743 /// various kinds of derived-to-base conversions (C++ 3744 /// [over.ics.rank]p4b3). As part of these checks, we also look at 3745 /// conversions between Objective-C interface types. 3746 ImplicitConversionSequence::CompareKind 3747 CompareDerivedToBaseConversions(Sema &S, 3748 const StandardConversionSequence& SCS1, 3749 const StandardConversionSequence& SCS2) { 3750 QualType FromType1 = SCS1.getFromType(); 3751 QualType ToType1 = SCS1.getToType(1); 3752 QualType FromType2 = SCS2.getFromType(); 3753 QualType ToType2 = SCS2.getToType(1); 3754 3755 // Adjust the types we're converting from via the array-to-pointer 3756 // conversion, if we need to. 3757 if (SCS1.First == ICK_Array_To_Pointer) 3758 FromType1 = S.Context.getArrayDecayedType(FromType1); 3759 if (SCS2.First == ICK_Array_To_Pointer) 3760 FromType2 = S.Context.getArrayDecayedType(FromType2); 3761 3762 // Canonicalize all of the types. 3763 FromType1 = S.Context.getCanonicalType(FromType1); 3764 ToType1 = S.Context.getCanonicalType(ToType1); 3765 FromType2 = S.Context.getCanonicalType(FromType2); 3766 ToType2 = S.Context.getCanonicalType(ToType2); 3767 3768 // C++ [over.ics.rank]p4b3: 3769 // 3770 // If class B is derived directly or indirectly from class A and 3771 // class C is derived directly or indirectly from B, 3772 // 3773 // Compare based on pointer conversions. 3774 if (SCS1.Second == ICK_Pointer_Conversion && 3775 SCS2.Second == ICK_Pointer_Conversion && 3776 /*FIXME: Remove if Objective-C id conversions get their own rank*/ 3777 FromType1->isPointerType() && FromType2->isPointerType() && 3778 ToType1->isPointerType() && ToType2->isPointerType()) { 3779 QualType FromPointee1 3780 = FromType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3781 QualType ToPointee1 3782 = ToType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3783 QualType FromPointee2 3784 = FromType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3785 QualType ToPointee2 3786 = ToType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3787 3788 // -- conversion of C* to B* is better than conversion of C* to A*, 3789 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 3790 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 3791 return ImplicitConversionSequence::Better; 3792 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 3793 return ImplicitConversionSequence::Worse; 3794 } 3795 3796 // -- conversion of B* to A* is better than conversion of C* to A*, 3797 if (FromPointee1 != FromPointee2 && ToPointee1 == ToPointee2) { 3798 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 3799 return ImplicitConversionSequence::Better; 3800 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 3801 return ImplicitConversionSequence::Worse; 3802 } 3803 } else if (SCS1.Second == ICK_Pointer_Conversion && 3804 SCS2.Second == ICK_Pointer_Conversion) { 3805 const ObjCObjectPointerType *FromPtr1 3806 = FromType1->getAs<ObjCObjectPointerType>(); 3807 const ObjCObjectPointerType *FromPtr2 3808 = FromType2->getAs<ObjCObjectPointerType>(); 3809 const ObjCObjectPointerType *ToPtr1 3810 = ToType1->getAs<ObjCObjectPointerType>(); 3811 const ObjCObjectPointerType *ToPtr2 3812 = ToType2->getAs<ObjCObjectPointerType>(); 3813 3814 if (FromPtr1 && FromPtr2 && ToPtr1 && ToPtr2) { 3815 // Apply the same conversion ranking rules for Objective-C pointer types 3816 // that we do for C++ pointers to class types. However, we employ the 3817 // Objective-C pseudo-subtyping relationship used for assignment of 3818 // Objective-C pointer types. 3819 bool FromAssignLeft 3820 = S.Context.canAssignObjCInterfaces(FromPtr1, FromPtr2); 3821 bool FromAssignRight 3822 = S.Context.canAssignObjCInterfaces(FromPtr2, FromPtr1); 3823 bool ToAssignLeft 3824 = S.Context.canAssignObjCInterfaces(ToPtr1, ToPtr2); 3825 bool ToAssignRight 3826 = S.Context.canAssignObjCInterfaces(ToPtr2, ToPtr1); 3827 3828 // A conversion to an a non-id object pointer type or qualified 'id' 3829 // type is better than a conversion to 'id'. 3830 if (ToPtr1->isObjCIdType() && 3831 (ToPtr2->isObjCQualifiedIdType() || ToPtr2->getInterfaceDecl())) 3832 return ImplicitConversionSequence::Worse; 3833 if (ToPtr2->isObjCIdType() && 3834 (ToPtr1->isObjCQualifiedIdType() || ToPtr1->getInterfaceDecl())) 3835 return ImplicitConversionSequence::Better; 3836 3837 // A conversion to a non-id object pointer type is better than a 3838 // conversion to a qualified 'id' type 3839 if (ToPtr1->isObjCQualifiedIdType() && ToPtr2->getInterfaceDecl()) 3840 return ImplicitConversionSequence::Worse; 3841 if (ToPtr2->isObjCQualifiedIdType() && ToPtr1->getInterfaceDecl()) 3842 return ImplicitConversionSequence::Better; 3843 3844 // A conversion to an a non-Class object pointer type or qualified 'Class' 3845 // type is better than a conversion to 'Class'. 3846 if (ToPtr1->isObjCClassType() && 3847 (ToPtr2->isObjCQualifiedClassType() || ToPtr2->getInterfaceDecl())) 3848 return ImplicitConversionSequence::Worse; 3849 if (ToPtr2->isObjCClassType() && 3850 (ToPtr1->isObjCQualifiedClassType() || ToPtr1->getInterfaceDecl())) 3851 return ImplicitConversionSequence::Better; 3852 3853 // A conversion to a non-Class object pointer type is better than a 3854 // conversion to a qualified 'Class' type. 3855 if (ToPtr1->isObjCQualifiedClassType() && ToPtr2->getInterfaceDecl()) 3856 return ImplicitConversionSequence::Worse; 3857 if (ToPtr2->isObjCQualifiedClassType() && ToPtr1->getInterfaceDecl()) 3858 return ImplicitConversionSequence::Better; 3859 3860 // -- "conversion of C* to B* is better than conversion of C* to A*," 3861 if (S.Context.hasSameType(FromType1, FromType2) && 3862 !FromPtr1->isObjCIdType() && !FromPtr1->isObjCClassType() && 3863 (ToAssignLeft != ToAssignRight)) 3864 return ToAssignLeft? ImplicitConversionSequence::Worse 3865 : ImplicitConversionSequence::Better; 3866 3867 // -- "conversion of B* to A* is better than conversion of C* to A*," 3868 if (S.Context.hasSameUnqualifiedType(ToType1, ToType2) && 3869 (FromAssignLeft != FromAssignRight)) 3870 return FromAssignLeft? ImplicitConversionSequence::Better 3871 : ImplicitConversionSequence::Worse; 3872 } 3873 } 3874 3875 // Ranking of member-pointer types. 3876 if (SCS1.Second == ICK_Pointer_Member && SCS2.Second == ICK_Pointer_Member && 3877 FromType1->isMemberPointerType() && FromType2->isMemberPointerType() && 3878 ToType1->isMemberPointerType() && ToType2->isMemberPointerType()) { 3879 const MemberPointerType * FromMemPointer1 = 3880 FromType1->getAs<MemberPointerType>(); 3881 const MemberPointerType * ToMemPointer1 = 3882 ToType1->getAs<MemberPointerType>(); 3883 const MemberPointerType * FromMemPointer2 = 3884 FromType2->getAs<MemberPointerType>(); 3885 const MemberPointerType * ToMemPointer2 = 3886 ToType2->getAs<MemberPointerType>(); 3887 const Type *FromPointeeType1 = FromMemPointer1->getClass(); 3888 const Type *ToPointeeType1 = ToMemPointer1->getClass(); 3889 const Type *FromPointeeType2 = FromMemPointer2->getClass(); 3890 const Type *ToPointeeType2 = ToMemPointer2->getClass(); 3891 QualType FromPointee1 = QualType(FromPointeeType1, 0).getUnqualifiedType(); 3892 QualType ToPointee1 = QualType(ToPointeeType1, 0).getUnqualifiedType(); 3893 QualType FromPointee2 = QualType(FromPointeeType2, 0).getUnqualifiedType(); 3894 QualType ToPointee2 = QualType(ToPointeeType2, 0).getUnqualifiedType(); 3895 // conversion of A::* to B::* is better than conversion of A::* to C::*, 3896 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 3897 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 3898 return ImplicitConversionSequence::Worse; 3899 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 3900 return ImplicitConversionSequence::Better; 3901 } 3902 // conversion of B::* to C::* is better than conversion of A::* to C::* 3903 if (ToPointee1 == ToPointee2 && FromPointee1 != FromPointee2) { 3904 if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 3905 return ImplicitConversionSequence::Better; 3906 else if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 3907 return ImplicitConversionSequence::Worse; 3908 } 3909 } 3910 3911 if (SCS1.Second == ICK_Derived_To_Base) { 3912 // -- conversion of C to B is better than conversion of C to A, 3913 // -- binding of an expression of type C to a reference of type 3914 // B& is better than binding an expression of type C to a 3915 // reference of type A&, 3916 if (S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3917 !S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3918 if (S.IsDerivedFrom(ToType1, ToType2)) 3919 return ImplicitConversionSequence::Better; 3920 else if (S.IsDerivedFrom(ToType2, ToType1)) 3921 return ImplicitConversionSequence::Worse; 3922 } 3923 3924 // -- conversion of B to A is better than conversion of C to A. 3925 // -- binding of an expression of type B to a reference of type 3926 // A& is better than binding an expression of type C to a 3927 // reference of type A&, 3928 if (!S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3929 S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3930 if (S.IsDerivedFrom(FromType2, FromType1)) 3931 return ImplicitConversionSequence::Better; 3932 else if (S.IsDerivedFrom(FromType1, FromType2)) 3933 return ImplicitConversionSequence::Worse; 3934 } 3935 } 3936 3937 return ImplicitConversionSequence::Indistinguishable; 3938 } 3939 3940 /// CompareReferenceRelationship - Compare the two types T1 and T2 to 3941 /// determine whether they are reference-related, 3942 /// reference-compatible, reference-compatible with added 3943 /// qualification, or incompatible, for use in C++ initialization by 3944 /// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 3945 /// type, and the first type (T1) is the pointee type of the reference 3946 /// type being initialized. 3947 Sema::ReferenceCompareResult 3948 Sema::CompareReferenceRelationship(SourceLocation Loc, 3949 QualType OrigT1, QualType OrigT2, 3950 bool &DerivedToBase, 3951 bool &ObjCConversion, 3952 bool &ObjCLifetimeConversion) { 3953 assert(!OrigT1->isReferenceType() && 3954 "T1 must be the pointee type of the reference type"); 3955 assert(!OrigT2->isReferenceType() && "T2 cannot be a reference type"); 3956 3957 QualType T1 = Context.getCanonicalType(OrigT1); 3958 QualType T2 = Context.getCanonicalType(OrigT2); 3959 Qualifiers T1Quals, T2Quals; 3960 QualType UnqualT1 = Context.getUnqualifiedArrayType(T1, T1Quals); 3961 QualType UnqualT2 = Context.getUnqualifiedArrayType(T2, T2Quals); 3962 3963 // C++ [dcl.init.ref]p4: 3964 // Given types "cv1 T1" and "cv2 T2," "cv1 T1" is 3965 // reference-related to "cv2 T2" if T1 is the same type as T2, or 3966 // T1 is a base class of T2. 3967 DerivedToBase = false; 3968 ObjCConversion = false; 3969 ObjCLifetimeConversion = false; 3970 if (UnqualT1 == UnqualT2) { 3971 // Nothing to do. 3972 } else if (!RequireCompleteType(Loc, OrigT2, 0) && 3973 IsDerivedFrom(UnqualT2, UnqualT1)) 3974 DerivedToBase = true; 3975 else if (UnqualT1->isObjCObjectOrInterfaceType() && 3976 UnqualT2->isObjCObjectOrInterfaceType() && 3977 Context.canBindObjCObjectType(UnqualT1, UnqualT2)) 3978 ObjCConversion = true; 3979 else 3980 return Ref_Incompatible; 3981 3982 // At this point, we know that T1 and T2 are reference-related (at 3983 // least). 3984 3985 // If the type is an array type, promote the element qualifiers to the type 3986 // for comparison. 3987 if (isa<ArrayType>(T1) && T1Quals) 3988 T1 = Context.getQualifiedType(UnqualT1, T1Quals); 3989 if (isa<ArrayType>(T2) && T2Quals) 3990 T2 = Context.getQualifiedType(UnqualT2, T2Quals); 3991 3992 // C++ [dcl.init.ref]p4: 3993 // "cv1 T1" is reference-compatible with "cv2 T2" if T1 is 3994 // reference-related to T2 and cv1 is the same cv-qualification 3995 // as, or greater cv-qualification than, cv2. For purposes of 3996 // overload resolution, cases for which cv1 is greater 3997 // cv-qualification than cv2 are identified as 3998 // reference-compatible with added qualification (see 13.3.3.2). 3999 // 4000 // Note that we also require equivalence of Objective-C GC and address-space 4001 // qualifiers when performing these computations, so that e.g., an int in 4002 // address space 1 is not reference-compatible with an int in address 4003 // space 2. 4004 if (T1Quals.getObjCLifetime() != T2Quals.getObjCLifetime() && 4005 T1Quals.compatiblyIncludesObjCLifetime(T2Quals)) { 4006 T1Quals.removeObjCLifetime(); 4007 T2Quals.removeObjCLifetime(); 4008 ObjCLifetimeConversion = true; 4009 } 4010 4011 if (T1Quals == T2Quals) 4012 return Ref_Compatible; 4013 else if (T1Quals.compatiblyIncludes(T2Quals)) 4014 return Ref_Compatible_With_Added_Qualification; 4015 else 4016 return Ref_Related; 4017 } 4018 4019 /// \brief Look for a user-defined conversion to an value reference-compatible 4020 /// with DeclType. Return true if something definite is found. 4021 static bool 4022 FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS, 4023 QualType DeclType, SourceLocation DeclLoc, 4024 Expr *Init, QualType T2, bool AllowRvalues, 4025 bool AllowExplicit) { 4026 assert(T2->isRecordType() && "Can only find conversions of record types."); 4027 CXXRecordDecl *T2RecordDecl 4028 = dyn_cast<CXXRecordDecl>(T2->getAs<RecordType>()->getDecl()); 4029 4030 OverloadCandidateSet CandidateSet(DeclLoc); 4031 std::pair<CXXRecordDecl::conversion_iterator, 4032 CXXRecordDecl::conversion_iterator> 4033 Conversions = T2RecordDecl->getVisibleConversionFunctions(); 4034 for (CXXRecordDecl::conversion_iterator 4035 I = Conversions.first, E = Conversions.second; I != E; ++I) { 4036 NamedDecl *D = *I; 4037 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 4038 if (isa<UsingShadowDecl>(D)) 4039 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 4040 4041 FunctionTemplateDecl *ConvTemplate 4042 = dyn_cast<FunctionTemplateDecl>(D); 4043 CXXConversionDecl *Conv; 4044 if (ConvTemplate) 4045 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 4046 else 4047 Conv = cast<CXXConversionDecl>(D); 4048 4049 // If this is an explicit conversion, and we're not allowed to consider 4050 // explicit conversions, skip it. 4051 if (!AllowExplicit && Conv->isExplicit()) 4052 continue; 4053 4054 if (AllowRvalues) { 4055 bool DerivedToBase = false; 4056 bool ObjCConversion = false; 4057 bool ObjCLifetimeConversion = false; 4058 4059 // If we are initializing an rvalue reference, don't permit conversion 4060 // functions that return lvalues. 4061 if (!ConvTemplate && DeclType->isRValueReferenceType()) { 4062 const ReferenceType *RefType 4063 = Conv->getConversionType()->getAs<LValueReferenceType>(); 4064 if (RefType && !RefType->getPointeeType()->isFunctionType()) 4065 continue; 4066 } 4067 4068 if (!ConvTemplate && 4069 S.CompareReferenceRelationship( 4070 DeclLoc, 4071 Conv->getConversionType().getNonReferenceType() 4072 .getUnqualifiedType(), 4073 DeclType.getNonReferenceType().getUnqualifiedType(), 4074 DerivedToBase, ObjCConversion, ObjCLifetimeConversion) == 4075 Sema::Ref_Incompatible) 4076 continue; 4077 } else { 4078 // If the conversion function doesn't return a reference type, 4079 // it can't be considered for this conversion. An rvalue reference 4080 // is only acceptable if its referencee is a function type. 4081 4082 const ReferenceType *RefType = 4083 Conv->getConversionType()->getAs<ReferenceType>(); 4084 if (!RefType || 4085 (!RefType->isLValueReferenceType() && 4086 !RefType->getPointeeType()->isFunctionType())) 4087 continue; 4088 } 4089 4090 if (ConvTemplate) 4091 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), ActingDC, 4092 Init, DeclType, CandidateSet); 4093 else 4094 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Init, 4095 DeclType, CandidateSet); 4096 } 4097 4098 bool HadMultipleCandidates = (CandidateSet.size() > 1); 4099 4100 OverloadCandidateSet::iterator Best; 4101 switch (CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) { 4102 case OR_Success: 4103 // C++ [over.ics.ref]p1: 4104 // 4105 // [...] If the parameter binds directly to the result of 4106 // applying a conversion function to the argument 4107 // expression, the implicit conversion sequence is a 4108 // user-defined conversion sequence (13.3.3.1.2), with the 4109 // second standard conversion sequence either an identity 4110 // conversion or, if the conversion function returns an 4111 // entity of a type that is a derived class of the parameter 4112 // type, a derived-to-base Conversion. 4113 if (!Best->FinalConversion.DirectBinding) 4114 return false; 4115 4116 ICS.setUserDefined(); 4117 ICS.UserDefined.Before = Best->Conversions[0].Standard; 4118 ICS.UserDefined.After = Best->FinalConversion; 4119 ICS.UserDefined.HadMultipleCandidates = HadMultipleCandidates; 4120 ICS.UserDefined.ConversionFunction = Best->Function; 4121 ICS.UserDefined.FoundConversionFunction = Best->FoundDecl; 4122 ICS.UserDefined.EllipsisConversion = false; 4123 assert(ICS.UserDefined.After.ReferenceBinding && 4124 ICS.UserDefined.After.DirectBinding && 4125 "Expected a direct reference binding!"); 4126 return true; 4127 4128 case OR_Ambiguous: 4129 ICS.setAmbiguous(); 4130 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(); 4131 Cand != CandidateSet.end(); ++Cand) 4132 if (Cand->Viable) 4133 ICS.Ambiguous.addConversion(Cand->Function); 4134 return true; 4135 4136 case OR_No_Viable_Function: 4137 case OR_Deleted: 4138 // There was no suitable conversion, or we found a deleted 4139 // conversion; continue with other checks. 4140 return false; 4141 } 4142 4143 llvm_unreachable("Invalid OverloadResult!"); 4144 } 4145 4146 /// \brief Compute an implicit conversion sequence for reference 4147 /// initialization. 4148 static ImplicitConversionSequence 4149 TryReferenceInit(Sema &S, Expr *Init, QualType DeclType, 4150 SourceLocation DeclLoc, 4151 bool SuppressUserConversions, 4152 bool AllowExplicit) { 4153 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 4154 4155 // Most paths end in a failed conversion. 4156 ImplicitConversionSequence ICS; 4157 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 4158 4159 QualType T1 = DeclType->getAs<ReferenceType>()->getPointeeType(); 4160 QualType T2 = Init->getType(); 4161 4162 // If the initializer is the address of an overloaded function, try 4163 // to resolve the overloaded function. If all goes well, T2 is the 4164 // type of the resulting function. 4165 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) { 4166 DeclAccessPair Found; 4167 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Init, DeclType, 4168 false, Found)) 4169 T2 = Fn->getType(); 4170 } 4171 4172 // Compute some basic properties of the types and the initializer. 4173 bool isRValRef = DeclType->isRValueReferenceType(); 4174 bool DerivedToBase = false; 4175 bool ObjCConversion = false; 4176 bool ObjCLifetimeConversion = false; 4177 Expr::Classification InitCategory = Init->Classify(S.Context); 4178 Sema::ReferenceCompareResult RefRelationship 4179 = S.CompareReferenceRelationship(DeclLoc, T1, T2, DerivedToBase, 4180 ObjCConversion, ObjCLifetimeConversion); 4181 4182 4183 // C++0x [dcl.init.ref]p5: 4184 // A reference to type "cv1 T1" is initialized by an expression 4185 // of type "cv2 T2" as follows: 4186 4187 // -- If reference is an lvalue reference and the initializer expression 4188 if (!isRValRef) { 4189 // -- is an lvalue (but is not a bit-field), and "cv1 T1" is 4190 // reference-compatible with "cv2 T2," or 4191 // 4192 // Per C++ [over.ics.ref]p4, we don't check the bit-field property here. 4193 if (InitCategory.isLValue() && 4194 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 4195 // C++ [over.ics.ref]p1: 4196 // When a parameter of reference type binds directly (8.5.3) 4197 // to an argument expression, the implicit conversion sequence 4198 // is the identity conversion, unless the argument expression 4199 // has a type that is a derived class of the parameter type, 4200 // in which case the implicit conversion sequence is a 4201 // derived-to-base Conversion (13.3.3.1). 4202 ICS.setStandard(); 4203 ICS.Standard.First = ICK_Identity; 4204 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 4205 : ObjCConversion? ICK_Compatible_Conversion 4206 : ICK_Identity; 4207 ICS.Standard.Third = ICK_Identity; 4208 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 4209 ICS.Standard.setToType(0, T2); 4210 ICS.Standard.setToType(1, T1); 4211 ICS.Standard.setToType(2, T1); 4212 ICS.Standard.ReferenceBinding = true; 4213 ICS.Standard.DirectBinding = true; 4214 ICS.Standard.IsLvalueReference = !isRValRef; 4215 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 4216 ICS.Standard.BindsToRvalue = false; 4217 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 4218 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion; 4219 ICS.Standard.CopyConstructor = 0; 4220 4221 // Nothing more to do: the inaccessibility/ambiguity check for 4222 // derived-to-base conversions is suppressed when we're 4223 // computing the implicit conversion sequence (C++ 4224 // [over.best.ics]p2). 4225 return ICS; 4226 } 4227 4228 // -- has a class type (i.e., T2 is a class type), where T1 is 4229 // not reference-related to T2, and can be implicitly 4230 // converted to an lvalue of type "cv3 T3," where "cv1 T1" 4231 // is reference-compatible with "cv3 T3" 92) (this 4232 // conversion is selected by enumerating the applicable 4233 // conversion functions (13.3.1.6) and choosing the best 4234 // one through overload resolution (13.3)), 4235 if (!SuppressUserConversions && T2->isRecordType() && 4236 !S.RequireCompleteType(DeclLoc, T2, 0) && 4237 RefRelationship == Sema::Ref_Incompatible) { 4238 if (FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 4239 Init, T2, /*AllowRvalues=*/false, 4240 AllowExplicit)) 4241 return ICS; 4242 } 4243 } 4244 4245 // -- Otherwise, the reference shall be an lvalue reference to a 4246 // non-volatile const type (i.e., cv1 shall be const), or the reference 4247 // shall be an rvalue reference. 4248 // 4249 // We actually handle one oddity of C++ [over.ics.ref] at this 4250 // point, which is that, due to p2 (which short-circuits reference 4251 // binding by only attempting a simple conversion for non-direct 4252 // bindings) and p3's strange wording, we allow a const volatile 4253 // reference to bind to an rvalue. Hence the check for the presence 4254 // of "const" rather than checking for "const" being the only 4255 // qualifier. 4256 // This is also the point where rvalue references and lvalue inits no longer 4257 // go together. 4258 if (!isRValRef && (!T1.isConstQualified() || T1.isVolatileQualified())) 4259 return ICS; 4260 4261 // -- If the initializer expression 4262 // 4263 // -- is an xvalue, class prvalue, array prvalue or function 4264 // lvalue and "cv1 T1" is reference-compatible with "cv2 T2", or 4265 if (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification && 4266 (InitCategory.isXValue() || 4267 (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) || 4268 (InitCategory.isLValue() && T2->isFunctionType()))) { 4269 ICS.setStandard(); 4270 ICS.Standard.First = ICK_Identity; 4271 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 4272 : ObjCConversion? ICK_Compatible_Conversion 4273 : ICK_Identity; 4274 ICS.Standard.Third = ICK_Identity; 4275 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 4276 ICS.Standard.setToType(0, T2); 4277 ICS.Standard.setToType(1, T1); 4278 ICS.Standard.setToType(2, T1); 4279 ICS.Standard.ReferenceBinding = true; 4280 // In C++0x, this is always a direct binding. In C++98/03, it's a direct 4281 // binding unless we're binding to a class prvalue. 4282 // Note: Although xvalues wouldn't normally show up in C++98/03 code, we 4283 // allow the use of rvalue references in C++98/03 for the benefit of 4284 // standard library implementors; therefore, we need the xvalue check here. 4285 ICS.Standard.DirectBinding = 4286 S.getLangOpts().CPlusPlus11 || 4287 (InitCategory.isPRValue() && !T2->isRecordType()); 4288 ICS.Standard.IsLvalueReference = !isRValRef; 4289 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 4290 ICS.Standard.BindsToRvalue = InitCategory.isRValue(); 4291 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 4292 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion; 4293 ICS.Standard.CopyConstructor = 0; 4294 return ICS; 4295 } 4296 4297 // -- has a class type (i.e., T2 is a class type), where T1 is not 4298 // reference-related to T2, and can be implicitly converted to 4299 // an xvalue, class prvalue, or function lvalue of type 4300 // "cv3 T3", where "cv1 T1" is reference-compatible with 4301 // "cv3 T3", 4302 // 4303 // then the reference is bound to the value of the initializer 4304 // expression in the first case and to the result of the conversion 4305 // in the second case (or, in either case, to an appropriate base 4306 // class subobject). 4307 if (!SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 4308 T2->isRecordType() && !S.RequireCompleteType(DeclLoc, T2, 0) && 4309 FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 4310 Init, T2, /*AllowRvalues=*/true, 4311 AllowExplicit)) { 4312 // In the second case, if the reference is an rvalue reference 4313 // and the second standard conversion sequence of the 4314 // user-defined conversion sequence includes an lvalue-to-rvalue 4315 // conversion, the program is ill-formed. 4316 if (ICS.isUserDefined() && isRValRef && 4317 ICS.UserDefined.After.First == ICK_Lvalue_To_Rvalue) 4318 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 4319 4320 return ICS; 4321 } 4322 4323 // -- Otherwise, a temporary of type "cv1 T1" is created and 4324 // initialized from the initializer expression using the 4325 // rules for a non-reference copy initialization (8.5). The 4326 // reference is then bound to the temporary. If T1 is 4327 // reference-related to T2, cv1 must be the same 4328 // cv-qualification as, or greater cv-qualification than, 4329 // cv2; otherwise, the program is ill-formed. 4330 if (RefRelationship == Sema::Ref_Related) { 4331 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 4332 // we would be reference-compatible or reference-compatible with 4333 // added qualification. But that wasn't the case, so the reference 4334 // initialization fails. 4335 // 4336 // Note that we only want to check address spaces and cvr-qualifiers here. 4337 // ObjC GC and lifetime qualifiers aren't important. 4338 Qualifiers T1Quals = T1.getQualifiers(); 4339 Qualifiers T2Quals = T2.getQualifiers(); 4340 T1Quals.removeObjCGCAttr(); 4341 T1Quals.removeObjCLifetime(); 4342 T2Quals.removeObjCGCAttr(); 4343 T2Quals.removeObjCLifetime(); 4344 if (!T1Quals.compatiblyIncludes(T2Quals)) 4345 return ICS; 4346 } 4347 4348 // If at least one of the types is a class type, the types are not 4349 // related, and we aren't allowed any user conversions, the 4350 // reference binding fails. This case is important for breaking 4351 // recursion, since TryImplicitConversion below will attempt to 4352 // create a temporary through the use of a copy constructor. 4353 if (SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 4354 (T1->isRecordType() || T2->isRecordType())) 4355 return ICS; 4356 4357 // If T1 is reference-related to T2 and the reference is an rvalue 4358 // reference, the initializer expression shall not be an lvalue. 4359 if (RefRelationship >= Sema::Ref_Related && 4360 isRValRef && Init->Classify(S.Context).isLValue()) 4361 return ICS; 4362 4363 // C++ [over.ics.ref]p2: 4364 // When a parameter of reference type is not bound directly to 4365 // an argument expression, the conversion sequence is the one 4366 // required to convert the argument expression to the 4367 // underlying type of the reference according to 4368 // 13.3.3.1. Conceptually, this conversion sequence corresponds 4369 // to copy-initializing a temporary of the underlying type with 4370 // the argument expression. Any difference in top-level 4371 // cv-qualification is subsumed by the initialization itself 4372 // and does not constitute a conversion. 4373 ICS = TryImplicitConversion(S, Init, T1, SuppressUserConversions, 4374 /*AllowExplicit=*/false, 4375 /*InOverloadResolution=*/false, 4376 /*CStyle=*/false, 4377 /*AllowObjCWritebackConversion=*/false); 4378 4379 // Of course, that's still a reference binding. 4380 if (ICS.isStandard()) { 4381 ICS.Standard.ReferenceBinding = true; 4382 ICS.Standard.IsLvalueReference = !isRValRef; 4383 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 4384 ICS.Standard.BindsToRvalue = true; 4385 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 4386 ICS.Standard.ObjCLifetimeConversionBinding = false; 4387 } else if (ICS.isUserDefined()) { 4388 // Don't allow rvalue references to bind to lvalues. 4389 if (DeclType->isRValueReferenceType()) { 4390 if (const ReferenceType *RefType 4391 = ICS.UserDefined.ConversionFunction->getResultType() 4392 ->getAs<LValueReferenceType>()) { 4393 if (!RefType->getPointeeType()->isFunctionType()) { 4394 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, Init, 4395 DeclType); 4396 return ICS; 4397 } 4398 } 4399 } 4400 4401 ICS.UserDefined.After.ReferenceBinding = true; 4402 ICS.UserDefined.After.IsLvalueReference = !isRValRef; 4403 ICS.UserDefined.After.BindsToFunctionLvalue = T2->isFunctionType(); 4404 ICS.UserDefined.After.BindsToRvalue = true; 4405 ICS.UserDefined.After.BindsImplicitObjectArgumentWithoutRefQualifier = false; 4406 ICS.UserDefined.After.ObjCLifetimeConversionBinding = false; 4407 } 4408 4409 return ICS; 4410 } 4411 4412 static ImplicitConversionSequence 4413 TryCopyInitialization(Sema &S, Expr *From, QualType ToType, 4414 bool SuppressUserConversions, 4415 bool InOverloadResolution, 4416 bool AllowObjCWritebackConversion, 4417 bool AllowExplicit = false); 4418 4419 /// TryListConversion - Try to copy-initialize a value of type ToType from the 4420 /// initializer list From. 4421 static ImplicitConversionSequence 4422 TryListConversion(Sema &S, InitListExpr *From, QualType ToType, 4423 bool SuppressUserConversions, 4424 bool InOverloadResolution, 4425 bool AllowObjCWritebackConversion) { 4426 // C++11 [over.ics.list]p1: 4427 // When an argument is an initializer list, it is not an expression and 4428 // special rules apply for converting it to a parameter type. 4429 4430 ImplicitConversionSequence Result; 4431 Result.setBad(BadConversionSequence::no_conversion, From, ToType); 4432 Result.setListInitializationSequence(); 4433 4434 // We need a complete type for what follows. Incomplete types can never be 4435 // initialized from init lists. 4436 if (S.RequireCompleteType(From->getLocStart(), ToType, 0)) 4437 return Result; 4438 4439 // C++11 [over.ics.list]p2: 4440 // If the parameter type is std::initializer_list<X> or "array of X" and 4441 // all the elements can be implicitly converted to X, the implicit 4442 // conversion sequence is the worst conversion necessary to convert an 4443 // element of the list to X. 4444 bool toStdInitializerList = false; 4445 QualType X; 4446 if (ToType->isArrayType()) 4447 X = S.Context.getAsArrayType(ToType)->getElementType(); 4448 else 4449 toStdInitializerList = S.isStdInitializerList(ToType, &X); 4450 if (!X.isNull()) { 4451 for (unsigned i = 0, e = From->getNumInits(); i < e; ++i) { 4452 Expr *Init = From->getInit(i); 4453 ImplicitConversionSequence ICS = 4454 TryCopyInitialization(S, Init, X, SuppressUserConversions, 4455 InOverloadResolution, 4456 AllowObjCWritebackConversion); 4457 // If a single element isn't convertible, fail. 4458 if (ICS.isBad()) { 4459 Result = ICS; 4460 break; 4461 } 4462 // Otherwise, look for the worst conversion. 4463 if (Result.isBad() || 4464 CompareImplicitConversionSequences(S, ICS, Result) == 4465 ImplicitConversionSequence::Worse) 4466 Result = ICS; 4467 } 4468 4469 // For an empty list, we won't have computed any conversion sequence. 4470 // Introduce the identity conversion sequence. 4471 if (From->getNumInits() == 0) { 4472 Result.setStandard(); 4473 Result.Standard.setAsIdentityConversion(); 4474 Result.Standard.setFromType(ToType); 4475 Result.Standard.setAllToTypes(ToType); 4476 } 4477 4478 Result.setListInitializationSequence(); 4479 Result.setStdInitializerListElement(toStdInitializerList); 4480 return Result; 4481 } 4482 4483 // C++11 [over.ics.list]p3: 4484 // Otherwise, if the parameter is a non-aggregate class X and overload 4485 // resolution chooses a single best constructor [...] the implicit 4486 // conversion sequence is a user-defined conversion sequence. If multiple 4487 // constructors are viable but none is better than the others, the 4488 // implicit conversion sequence is a user-defined conversion sequence. 4489 if (ToType->isRecordType() && !ToType->isAggregateType()) { 4490 // This function can deal with initializer lists. 4491 Result = TryUserDefinedConversion(S, From, ToType, SuppressUserConversions, 4492 /*AllowExplicit=*/false, 4493 InOverloadResolution, /*CStyle=*/false, 4494 AllowObjCWritebackConversion); 4495 Result.setListInitializationSequence(); 4496 return Result; 4497 } 4498 4499 // C++11 [over.ics.list]p4: 4500 // Otherwise, if the parameter has an aggregate type which can be 4501 // initialized from the initializer list [...] the implicit conversion 4502 // sequence is a user-defined conversion sequence. 4503 if (ToType->isAggregateType()) { 4504 // Type is an aggregate, argument is an init list. At this point it comes 4505 // down to checking whether the initialization works. 4506 // FIXME: Find out whether this parameter is consumed or not. 4507 InitializedEntity Entity = 4508 InitializedEntity::InitializeParameter(S.Context, ToType, 4509 /*Consumed=*/false); 4510 if (S.CanPerformCopyInitialization(Entity, S.Owned(From))) { 4511 Result.setUserDefined(); 4512 Result.UserDefined.Before.setAsIdentityConversion(); 4513 // Initializer lists don't have a type. 4514 Result.UserDefined.Before.setFromType(QualType()); 4515 Result.UserDefined.Before.setAllToTypes(QualType()); 4516 4517 Result.UserDefined.After.setAsIdentityConversion(); 4518 Result.UserDefined.After.setFromType(ToType); 4519 Result.UserDefined.After.setAllToTypes(ToType); 4520 Result.UserDefined.ConversionFunction = 0; 4521 } 4522 return Result; 4523 } 4524 4525 // C++11 [over.ics.list]p5: 4526 // Otherwise, if the parameter is a reference, see 13.3.3.1.4. 4527 if (ToType->isReferenceType()) { 4528 // The standard is notoriously unclear here, since 13.3.3.1.4 doesn't 4529 // mention initializer lists in any way. So we go by what list- 4530 // initialization would do and try to extrapolate from that. 4531 4532 QualType T1 = ToType->getAs<ReferenceType>()->getPointeeType(); 4533 4534 // If the initializer list has a single element that is reference-related 4535 // to the parameter type, we initialize the reference from that. 4536 if (From->getNumInits() == 1) { 4537 Expr *Init = From->getInit(0); 4538 4539 QualType T2 = Init->getType(); 4540 4541 // If the initializer is the address of an overloaded function, try 4542 // to resolve the overloaded function. If all goes well, T2 is the 4543 // type of the resulting function. 4544 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) { 4545 DeclAccessPair Found; 4546 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction( 4547 Init, ToType, false, Found)) 4548 T2 = Fn->getType(); 4549 } 4550 4551 // Compute some basic properties of the types and the initializer. 4552 bool dummy1 = false; 4553 bool dummy2 = false; 4554 bool dummy3 = false; 4555 Sema::ReferenceCompareResult RefRelationship 4556 = S.CompareReferenceRelationship(From->getLocStart(), T1, T2, dummy1, 4557 dummy2, dummy3); 4558 4559 if (RefRelationship >= Sema::Ref_Related) 4560 return TryReferenceInit(S, Init, ToType, 4561 /*FIXME:*/From->getLocStart(), 4562 SuppressUserConversions, 4563 /*AllowExplicit=*/false); 4564 } 4565 4566 // Otherwise, we bind the reference to a temporary created from the 4567 // initializer list. 4568 Result = TryListConversion(S, From, T1, SuppressUserConversions, 4569 InOverloadResolution, 4570 AllowObjCWritebackConversion); 4571 if (Result.isFailure()) 4572 return Result; 4573 assert(!Result.isEllipsis() && 4574 "Sub-initialization cannot result in ellipsis conversion."); 4575 4576 // Can we even bind to a temporary? 4577 if (ToType->isRValueReferenceType() || 4578 (T1.isConstQualified() && !T1.isVolatileQualified())) { 4579 StandardConversionSequence &SCS = Result.isStandard() ? Result.Standard : 4580 Result.UserDefined.After; 4581 SCS.ReferenceBinding = true; 4582 SCS.IsLvalueReference = ToType->isLValueReferenceType(); 4583 SCS.BindsToRvalue = true; 4584 SCS.BindsToFunctionLvalue = false; 4585 SCS.BindsImplicitObjectArgumentWithoutRefQualifier = false; 4586 SCS.ObjCLifetimeConversionBinding = false; 4587 } else 4588 Result.setBad(BadConversionSequence::lvalue_ref_to_rvalue, 4589 From, ToType); 4590 return Result; 4591 } 4592 4593 // C++11 [over.ics.list]p6: 4594 // Otherwise, if the parameter type is not a class: 4595 if (!ToType->isRecordType()) { 4596 // - if the initializer list has one element, the implicit conversion 4597 // sequence is the one required to convert the element to the 4598 // parameter type. 4599 unsigned NumInits = From->getNumInits(); 4600 if (NumInits == 1) 4601 Result = TryCopyInitialization(S, From->getInit(0), ToType, 4602 SuppressUserConversions, 4603 InOverloadResolution, 4604 AllowObjCWritebackConversion); 4605 // - if the initializer list has no elements, the implicit conversion 4606 // sequence is the identity conversion. 4607 else if (NumInits == 0) { 4608 Result.setStandard(); 4609 Result.Standard.setAsIdentityConversion(); 4610 Result.Standard.setFromType(ToType); 4611 Result.Standard.setAllToTypes(ToType); 4612 } 4613 Result.setListInitializationSequence(); 4614 return Result; 4615 } 4616 4617 // C++11 [over.ics.list]p7: 4618 // In all cases other than those enumerated above, no conversion is possible 4619 return Result; 4620 } 4621 4622 /// TryCopyInitialization - Try to copy-initialize a value of type 4623 /// ToType from the expression From. Return the implicit conversion 4624 /// sequence required to pass this argument, which may be a bad 4625 /// conversion sequence (meaning that the argument cannot be passed to 4626 /// a parameter of this type). If @p SuppressUserConversions, then we 4627 /// do not permit any user-defined conversion sequences. 4628 static ImplicitConversionSequence 4629 TryCopyInitialization(Sema &S, Expr *From, QualType ToType, 4630 bool SuppressUserConversions, 4631 bool InOverloadResolution, 4632 bool AllowObjCWritebackConversion, 4633 bool AllowExplicit) { 4634 if (InitListExpr *FromInitList = dyn_cast<InitListExpr>(From)) 4635 return TryListConversion(S, FromInitList, ToType, SuppressUserConversions, 4636 InOverloadResolution,AllowObjCWritebackConversion); 4637 4638 if (ToType->isReferenceType()) 4639 return TryReferenceInit(S, From, ToType, 4640 /*FIXME:*/From->getLocStart(), 4641 SuppressUserConversions, 4642 AllowExplicit); 4643 4644 return TryImplicitConversion(S, From, ToType, 4645 SuppressUserConversions, 4646 /*AllowExplicit=*/false, 4647 InOverloadResolution, 4648 /*CStyle=*/false, 4649 AllowObjCWritebackConversion); 4650 } 4651 4652 static bool TryCopyInitialization(const CanQualType FromQTy, 4653 const CanQualType ToQTy, 4654 Sema &S, 4655 SourceLocation Loc, 4656 ExprValueKind FromVK) { 4657 OpaqueValueExpr TmpExpr(Loc, FromQTy, FromVK); 4658 ImplicitConversionSequence ICS = 4659 TryCopyInitialization(S, &TmpExpr, ToQTy, true, true, false); 4660 4661 return !ICS.isBad(); 4662 } 4663 4664 /// TryObjectArgumentInitialization - Try to initialize the object 4665 /// parameter of the given member function (@c Method) from the 4666 /// expression @p From. 4667 static ImplicitConversionSequence 4668 TryObjectArgumentInitialization(Sema &S, QualType FromType, 4669 Expr::Classification FromClassification, 4670 CXXMethodDecl *Method, 4671 CXXRecordDecl *ActingContext) { 4672 QualType ClassType = S.Context.getTypeDeclType(ActingContext); 4673 // [class.dtor]p2: A destructor can be invoked for a const, volatile or 4674 // const volatile object. 4675 unsigned Quals = isa<CXXDestructorDecl>(Method) ? 4676 Qualifiers::Const | Qualifiers::Volatile : Method->getTypeQualifiers(); 4677 QualType ImplicitParamType = S.Context.getCVRQualifiedType(ClassType, Quals); 4678 4679 // Set up the conversion sequence as a "bad" conversion, to allow us 4680 // to exit early. 4681 ImplicitConversionSequence ICS; 4682 4683 // We need to have an object of class type. 4684 if (const PointerType *PT = FromType->getAs<PointerType>()) { 4685 FromType = PT->getPointeeType(); 4686 4687 // When we had a pointer, it's implicitly dereferenced, so we 4688 // better have an lvalue. 4689 assert(FromClassification.isLValue()); 4690 } 4691 4692 assert(FromType->isRecordType()); 4693 4694 // C++0x [over.match.funcs]p4: 4695 // For non-static member functions, the type of the implicit object 4696 // parameter is 4697 // 4698 // - "lvalue reference to cv X" for functions declared without a 4699 // ref-qualifier or with the & ref-qualifier 4700 // - "rvalue reference to cv X" for functions declared with the && 4701 // ref-qualifier 4702 // 4703 // where X is the class of which the function is a member and cv is the 4704 // cv-qualification on the member function declaration. 4705 // 4706 // However, when finding an implicit conversion sequence for the argument, we 4707 // are not allowed to create temporaries or perform user-defined conversions 4708 // (C++ [over.match.funcs]p5). We perform a simplified version of 4709 // reference binding here, that allows class rvalues to bind to 4710 // non-constant references. 4711 4712 // First check the qualifiers. 4713 QualType FromTypeCanon = S.Context.getCanonicalType(FromType); 4714 if (ImplicitParamType.getCVRQualifiers() 4715 != FromTypeCanon.getLocalCVRQualifiers() && 4716 !ImplicitParamType.isAtLeastAsQualifiedAs(FromTypeCanon)) { 4717 ICS.setBad(BadConversionSequence::bad_qualifiers, 4718 FromType, ImplicitParamType); 4719 return ICS; 4720 } 4721 4722 // Check that we have either the same type or a derived type. It 4723 // affects the conversion rank. 4724 QualType ClassTypeCanon = S.Context.getCanonicalType(ClassType); 4725 ImplicitConversionKind SecondKind; 4726 if (ClassTypeCanon == FromTypeCanon.getLocalUnqualifiedType()) { 4727 SecondKind = ICK_Identity; 4728 } else if (S.IsDerivedFrom(FromType, ClassType)) 4729 SecondKind = ICK_Derived_To_Base; 4730 else { 4731 ICS.setBad(BadConversionSequence::unrelated_class, 4732 FromType, ImplicitParamType); 4733 return ICS; 4734 } 4735 4736 // Check the ref-qualifier. 4737 switch (Method->getRefQualifier()) { 4738 case RQ_None: 4739 // Do nothing; we don't care about lvalueness or rvalueness. 4740 break; 4741 4742 case RQ_LValue: 4743 if (!FromClassification.isLValue() && Quals != Qualifiers::Const) { 4744 // non-const lvalue reference cannot bind to an rvalue 4745 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, FromType, 4746 ImplicitParamType); 4747 return ICS; 4748 } 4749 break; 4750 4751 case RQ_RValue: 4752 if (!FromClassification.isRValue()) { 4753 // rvalue reference cannot bind to an lvalue 4754 ICS.setBad(BadConversionSequence::rvalue_ref_to_lvalue, FromType, 4755 ImplicitParamType); 4756 return ICS; 4757 } 4758 break; 4759 } 4760 4761 // Success. Mark this as a reference binding. 4762 ICS.setStandard(); 4763 ICS.Standard.setAsIdentityConversion(); 4764 ICS.Standard.Second = SecondKind; 4765 ICS.Standard.setFromType(FromType); 4766 ICS.Standard.setAllToTypes(ImplicitParamType); 4767 ICS.Standard.ReferenceBinding = true; 4768 ICS.Standard.DirectBinding = true; 4769 ICS.Standard.IsLvalueReference = Method->getRefQualifier() != RQ_RValue; 4770 ICS.Standard.BindsToFunctionLvalue = false; 4771 ICS.Standard.BindsToRvalue = FromClassification.isRValue(); 4772 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier 4773 = (Method->getRefQualifier() == RQ_None); 4774 return ICS; 4775 } 4776 4777 /// PerformObjectArgumentInitialization - Perform initialization of 4778 /// the implicit object parameter for the given Method with the given 4779 /// expression. 4780 ExprResult 4781 Sema::PerformObjectArgumentInitialization(Expr *From, 4782 NestedNameSpecifier *Qualifier, 4783 NamedDecl *FoundDecl, 4784 CXXMethodDecl *Method) { 4785 QualType FromRecordType, DestType; 4786 QualType ImplicitParamRecordType = 4787 Method->getThisType(Context)->getAs<PointerType>()->getPointeeType(); 4788 4789 Expr::Classification FromClassification; 4790 if (const PointerType *PT = From->getType()->getAs<PointerType>()) { 4791 FromRecordType = PT->getPointeeType(); 4792 DestType = Method->getThisType(Context); 4793 FromClassification = Expr::Classification::makeSimpleLValue(); 4794 } else { 4795 FromRecordType = From->getType(); 4796 DestType = ImplicitParamRecordType; 4797 FromClassification = From->Classify(Context); 4798 } 4799 4800 // Note that we always use the true parent context when performing 4801 // the actual argument initialization. 4802 ImplicitConversionSequence ICS 4803 = TryObjectArgumentInitialization(*this, From->getType(), FromClassification, 4804 Method, Method->getParent()); 4805 if (ICS.isBad()) { 4806 if (ICS.Bad.Kind == BadConversionSequence::bad_qualifiers) { 4807 Qualifiers FromQs = FromRecordType.getQualifiers(); 4808 Qualifiers ToQs = DestType.getQualifiers(); 4809 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 4810 if (CVR) { 4811 Diag(From->getLocStart(), 4812 diag::err_member_function_call_bad_cvr) 4813 << Method->getDeclName() << FromRecordType << (CVR - 1) 4814 << From->getSourceRange(); 4815 Diag(Method->getLocation(), diag::note_previous_decl) 4816 << Method->getDeclName(); 4817 return ExprError(); 4818 } 4819 } 4820 4821 return Diag(From->getLocStart(), 4822 diag::err_implicit_object_parameter_init) 4823 << ImplicitParamRecordType << FromRecordType << From->getSourceRange(); 4824 } 4825 4826 if (ICS.Standard.Second == ICK_Derived_To_Base) { 4827 ExprResult FromRes = 4828 PerformObjectMemberConversion(From, Qualifier, FoundDecl, Method); 4829 if (FromRes.isInvalid()) 4830 return ExprError(); 4831 From = FromRes.take(); 4832 } 4833 4834 if (!Context.hasSameType(From->getType(), DestType)) 4835 From = ImpCastExprToType(From, DestType, CK_NoOp, 4836 From->getValueKind()).take(); 4837 return Owned(From); 4838 } 4839 4840 /// TryContextuallyConvertToBool - Attempt to contextually convert the 4841 /// expression From to bool (C++0x [conv]p3). 4842 static ImplicitConversionSequence 4843 TryContextuallyConvertToBool(Sema &S, Expr *From) { 4844 // FIXME: This is pretty broken. 4845 return TryImplicitConversion(S, From, S.Context.BoolTy, 4846 // FIXME: Are these flags correct? 4847 /*SuppressUserConversions=*/false, 4848 /*AllowExplicit=*/true, 4849 /*InOverloadResolution=*/false, 4850 /*CStyle=*/false, 4851 /*AllowObjCWritebackConversion=*/false); 4852 } 4853 4854 /// PerformContextuallyConvertToBool - Perform a contextual conversion 4855 /// of the expression From to bool (C++0x [conv]p3). 4856 ExprResult Sema::PerformContextuallyConvertToBool(Expr *From) { 4857 if (checkPlaceholderForOverload(*this, From)) 4858 return ExprError(); 4859 4860 ImplicitConversionSequence ICS = TryContextuallyConvertToBool(*this, From); 4861 if (!ICS.isBad()) 4862 return PerformImplicitConversion(From, Context.BoolTy, ICS, AA_Converting); 4863 4864 if (!DiagnoseMultipleUserDefinedConversion(From, Context.BoolTy)) 4865 return Diag(From->getLocStart(), 4866 diag::err_typecheck_bool_condition) 4867 << From->getType() << From->getSourceRange(); 4868 return ExprError(); 4869 } 4870 4871 /// Check that the specified conversion is permitted in a converted constant 4872 /// expression, according to C++11 [expr.const]p3. Return true if the conversion 4873 /// is acceptable. 4874 static bool CheckConvertedConstantConversions(Sema &S, 4875 StandardConversionSequence &SCS) { 4876 // Since we know that the target type is an integral or unscoped enumeration 4877 // type, most conversion kinds are impossible. All possible First and Third 4878 // conversions are fine. 4879 switch (SCS.Second) { 4880 case ICK_Identity: 4881 case ICK_Integral_Promotion: 4882 case ICK_Integral_Conversion: 4883 case ICK_Zero_Event_Conversion: 4884 return true; 4885 4886 case ICK_Boolean_Conversion: 4887 // Conversion from an integral or unscoped enumeration type to bool is 4888 // classified as ICK_Boolean_Conversion, but it's also an integral 4889 // conversion, so it's permitted in a converted constant expression. 4890 return SCS.getFromType()->isIntegralOrUnscopedEnumerationType() && 4891 SCS.getToType(2)->isBooleanType(); 4892 4893 case ICK_Floating_Integral: 4894 case ICK_Complex_Real: 4895 return false; 4896 4897 case ICK_Lvalue_To_Rvalue: 4898 case ICK_Array_To_Pointer: 4899 case ICK_Function_To_Pointer: 4900 case ICK_NoReturn_Adjustment: 4901 case ICK_Qualification: 4902 case ICK_Compatible_Conversion: 4903 case ICK_Vector_Conversion: 4904 case ICK_Vector_Splat: 4905 case ICK_Derived_To_Base: 4906 case ICK_Pointer_Conversion: 4907 case ICK_Pointer_Member: 4908 case ICK_Block_Pointer_Conversion: 4909 case ICK_Writeback_Conversion: 4910 case ICK_Floating_Promotion: 4911 case ICK_Complex_Promotion: 4912 case ICK_Complex_Conversion: 4913 case ICK_Floating_Conversion: 4914 case ICK_TransparentUnionConversion: 4915 llvm_unreachable("unexpected second conversion kind"); 4916 4917 case ICK_Num_Conversion_Kinds: 4918 break; 4919 } 4920 4921 llvm_unreachable("unknown conversion kind"); 4922 } 4923 4924 /// CheckConvertedConstantExpression - Check that the expression From is a 4925 /// converted constant expression of type T, perform the conversion and produce 4926 /// the converted expression, per C++11 [expr.const]p3. 4927 ExprResult Sema::CheckConvertedConstantExpression(Expr *From, QualType T, 4928 llvm::APSInt &Value, 4929 CCEKind CCE) { 4930 assert(LangOpts.CPlusPlus11 && "converted constant expression outside C++11"); 4931 assert(T->isIntegralOrEnumerationType() && "unexpected converted const type"); 4932 4933 if (checkPlaceholderForOverload(*this, From)) 4934 return ExprError(); 4935 4936 // C++11 [expr.const]p3 with proposed wording fixes: 4937 // A converted constant expression of type T is a core constant expression, 4938 // implicitly converted to a prvalue of type T, where the converted 4939 // expression is a literal constant expression and the implicit conversion 4940 // sequence contains only user-defined conversions, lvalue-to-rvalue 4941 // conversions, integral promotions, and integral conversions other than 4942 // narrowing conversions. 4943 ImplicitConversionSequence ICS = 4944 TryImplicitConversion(From, T, 4945 /*SuppressUserConversions=*/false, 4946 /*AllowExplicit=*/false, 4947 /*InOverloadResolution=*/false, 4948 /*CStyle=*/false, 4949 /*AllowObjcWritebackConversion=*/false); 4950 StandardConversionSequence *SCS = 0; 4951 switch (ICS.getKind()) { 4952 case ImplicitConversionSequence::StandardConversion: 4953 if (!CheckConvertedConstantConversions(*this, ICS.Standard)) 4954 return Diag(From->getLocStart(), 4955 diag::err_typecheck_converted_constant_expression_disallowed) 4956 << From->getType() << From->getSourceRange() << T; 4957 SCS = &ICS.Standard; 4958 break; 4959 case ImplicitConversionSequence::UserDefinedConversion: 4960 // We are converting from class type to an integral or enumeration type, so 4961 // the Before sequence must be trivial. 4962 if (!CheckConvertedConstantConversions(*this, ICS.UserDefined.After)) 4963 return Diag(From->getLocStart(), 4964 diag::err_typecheck_converted_constant_expression_disallowed) 4965 << From->getType() << From->getSourceRange() << T; 4966 SCS = &ICS.UserDefined.After; 4967 break; 4968 case ImplicitConversionSequence::AmbiguousConversion: 4969 case ImplicitConversionSequence::BadConversion: 4970 if (!DiagnoseMultipleUserDefinedConversion(From, T)) 4971 return Diag(From->getLocStart(), 4972 diag::err_typecheck_converted_constant_expression) 4973 << From->getType() << From->getSourceRange() << T; 4974 return ExprError(); 4975 4976 case ImplicitConversionSequence::EllipsisConversion: 4977 llvm_unreachable("ellipsis conversion in converted constant expression"); 4978 } 4979 4980 ExprResult Result = PerformImplicitConversion(From, T, ICS, AA_Converting); 4981 if (Result.isInvalid()) 4982 return Result; 4983 4984 // Check for a narrowing implicit conversion. 4985 APValue PreNarrowingValue; 4986 QualType PreNarrowingType; 4987 switch (SCS->getNarrowingKind(Context, Result.get(), PreNarrowingValue, 4988 PreNarrowingType)) { 4989 case NK_Variable_Narrowing: 4990 // Implicit conversion to a narrower type, and the value is not a constant 4991 // expression. We'll diagnose this in a moment. 4992 case NK_Not_Narrowing: 4993 break; 4994 4995 case NK_Constant_Narrowing: 4996 Diag(From->getLocStart(), 4997 isSFINAEContext() ? diag::err_cce_narrowing_sfinae : 4998 diag::err_cce_narrowing) 4999 << CCE << /*Constant*/1 5000 << PreNarrowingValue.getAsString(Context, PreNarrowingType) << T; 5001 break; 5002 5003 case NK_Type_Narrowing: 5004 Diag(From->getLocStart(), 5005 isSFINAEContext() ? diag::err_cce_narrowing_sfinae : 5006 diag::err_cce_narrowing) 5007 << CCE << /*Constant*/0 << From->getType() << T; 5008 break; 5009 } 5010 5011 // Check the expression is a constant expression. 5012 SmallVector<PartialDiagnosticAt, 8> Notes; 5013 Expr::EvalResult Eval; 5014 Eval.Diag = &Notes; 5015 5016 if (!Result.get()->EvaluateAsRValue(Eval, Context)) { 5017 // The expression can't be folded, so we can't keep it at this position in 5018 // the AST. 5019 Result = ExprError(); 5020 } else { 5021 Value = Eval.Val.getInt(); 5022 5023 if (Notes.empty()) { 5024 // It's a constant expression. 5025 return Result; 5026 } 5027 } 5028 5029 // It's not a constant expression. Produce an appropriate diagnostic. 5030 if (Notes.size() == 1 && 5031 Notes[0].second.getDiagID() == diag::note_invalid_subexpr_in_const_expr) 5032 Diag(Notes[0].first, diag::err_expr_not_cce) << CCE; 5033 else { 5034 Diag(From->getLocStart(), diag::err_expr_not_cce) 5035 << CCE << From->getSourceRange(); 5036 for (unsigned I = 0; I < Notes.size(); ++I) 5037 Diag(Notes[I].first, Notes[I].second); 5038 } 5039 return Result; 5040 } 5041 5042 /// dropPointerConversions - If the given standard conversion sequence 5043 /// involves any pointer conversions, remove them. This may change 5044 /// the result type of the conversion sequence. 5045 static void dropPointerConversion(StandardConversionSequence &SCS) { 5046 if (SCS.Second == ICK_Pointer_Conversion) { 5047 SCS.Second = ICK_Identity; 5048 SCS.Third = ICK_Identity; 5049 SCS.ToTypePtrs[2] = SCS.ToTypePtrs[1] = SCS.ToTypePtrs[0]; 5050 } 5051 } 5052 5053 /// TryContextuallyConvertToObjCPointer - Attempt to contextually 5054 /// convert the expression From to an Objective-C pointer type. 5055 static ImplicitConversionSequence 5056 TryContextuallyConvertToObjCPointer(Sema &S, Expr *From) { 5057 // Do an implicit conversion to 'id'. 5058 QualType Ty = S.Context.getObjCIdType(); 5059 ImplicitConversionSequence ICS 5060 = TryImplicitConversion(S, From, Ty, 5061 // FIXME: Are these flags correct? 5062 /*SuppressUserConversions=*/false, 5063 /*AllowExplicit=*/true, 5064 /*InOverloadResolution=*/false, 5065 /*CStyle=*/false, 5066 /*AllowObjCWritebackConversion=*/false); 5067 5068 // Strip off any final conversions to 'id'. 5069 switch (ICS.getKind()) { 5070 case ImplicitConversionSequence::BadConversion: 5071 case ImplicitConversionSequence::AmbiguousConversion: 5072 case ImplicitConversionSequence::EllipsisConversion: 5073 break; 5074 5075 case ImplicitConversionSequence::UserDefinedConversion: 5076 dropPointerConversion(ICS.UserDefined.After); 5077 break; 5078 5079 case ImplicitConversionSequence::StandardConversion: 5080 dropPointerConversion(ICS.Standard); 5081 break; 5082 } 5083 5084 return ICS; 5085 } 5086 5087 /// PerformContextuallyConvertToObjCPointer - Perform a contextual 5088 /// conversion of the expression From to an Objective-C pointer type. 5089 ExprResult Sema::PerformContextuallyConvertToObjCPointer(Expr *From) { 5090 if (checkPlaceholderForOverload(*this, From)) 5091 return ExprError(); 5092 5093 QualType Ty = Context.getObjCIdType(); 5094 ImplicitConversionSequence ICS = 5095 TryContextuallyConvertToObjCPointer(*this, From); 5096 if (!ICS.isBad()) 5097 return PerformImplicitConversion(From, Ty, ICS, AA_Converting); 5098 return ExprError(); 5099 } 5100 5101 /// Determine whether the provided type is an integral type, or an enumeration 5102 /// type of a permitted flavor. 5103 static bool isIntegralOrEnumerationType(QualType T, bool AllowScopedEnum) { 5104 return AllowScopedEnum ? T->isIntegralOrEnumerationType() 5105 : T->isIntegralOrUnscopedEnumerationType(); 5106 } 5107 5108 /// \brief Attempt to convert the given expression to an integral or 5109 /// enumeration type. 5110 /// 5111 /// This routine will attempt to convert an expression of class type to an 5112 /// integral or enumeration type, if that class type only has a single 5113 /// conversion to an integral or enumeration type. 5114 /// 5115 /// \param Loc The source location of the construct that requires the 5116 /// conversion. 5117 /// 5118 /// \param From The expression we're converting from. 5119 /// 5120 /// \param Diagnoser Used to output any diagnostics. 5121 /// 5122 /// \param AllowScopedEnumerations Specifies whether conversions to scoped 5123 /// enumerations should be considered. 5124 /// 5125 /// \returns The expression, converted to an integral or enumeration type if 5126 /// successful. 5127 ExprResult 5128 Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From, 5129 ICEConvertDiagnoser &Diagnoser, 5130 bool AllowScopedEnumerations) { 5131 // We can't perform any more checking for type-dependent expressions. 5132 if (From->isTypeDependent()) 5133 return Owned(From); 5134 5135 // Process placeholders immediately. 5136 if (From->hasPlaceholderType()) { 5137 ExprResult result = CheckPlaceholderExpr(From); 5138 if (result.isInvalid()) return result; 5139 From = result.take(); 5140 } 5141 5142 // If the expression already has integral or enumeration type, we're golden. 5143 QualType T = From->getType(); 5144 if (isIntegralOrEnumerationType(T, AllowScopedEnumerations)) 5145 return DefaultLvalueConversion(From); 5146 5147 // FIXME: Check for missing '()' if T is a function type? 5148 5149 // If we don't have a class type in C++, there's no way we can get an 5150 // expression of integral or enumeration type. 5151 const RecordType *RecordTy = T->getAs<RecordType>(); 5152 if (!RecordTy || !getLangOpts().CPlusPlus) { 5153 if (!Diagnoser.Suppress) 5154 Diagnoser.diagnoseNotInt(*this, Loc, T) << From->getSourceRange(); 5155 return Owned(From); 5156 } 5157 5158 // We must have a complete class type. 5159 struct TypeDiagnoserPartialDiag : TypeDiagnoser { 5160 ICEConvertDiagnoser &Diagnoser; 5161 Expr *From; 5162 5163 TypeDiagnoserPartialDiag(ICEConvertDiagnoser &Diagnoser, Expr *From) 5164 : TypeDiagnoser(Diagnoser.Suppress), Diagnoser(Diagnoser), From(From) {} 5165 5166 virtual void diagnose(Sema &S, SourceLocation Loc, QualType T) { 5167 Diagnoser.diagnoseIncomplete(S, Loc, T) << From->getSourceRange(); 5168 } 5169 } IncompleteDiagnoser(Diagnoser, From); 5170 5171 if (RequireCompleteType(Loc, T, IncompleteDiagnoser)) 5172 return Owned(From); 5173 5174 // Look for a conversion to an integral or enumeration type. 5175 UnresolvedSet<4> ViableConversions; 5176 UnresolvedSet<4> ExplicitConversions; 5177 std::pair<CXXRecordDecl::conversion_iterator, 5178 CXXRecordDecl::conversion_iterator> Conversions 5179 = cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions(); 5180 5181 bool HadMultipleCandidates 5182 = (std::distance(Conversions.first, Conversions.second) > 1); 5183 5184 for (CXXRecordDecl::conversion_iterator 5185 I = Conversions.first, E = Conversions.second; I != E; ++I) { 5186 if (CXXConversionDecl *Conversion 5187 = dyn_cast<CXXConversionDecl>((*I)->getUnderlyingDecl())) { 5188 if (isIntegralOrEnumerationType( 5189 Conversion->getConversionType().getNonReferenceType(), 5190 AllowScopedEnumerations)) { 5191 if (Conversion->isExplicit()) 5192 ExplicitConversions.addDecl(I.getDecl(), I.getAccess()); 5193 else 5194 ViableConversions.addDecl(I.getDecl(), I.getAccess()); 5195 } 5196 } 5197 } 5198 5199 switch (ViableConversions.size()) { 5200 case 0: 5201 if (ExplicitConversions.size() == 1 && !Diagnoser.Suppress) { 5202 DeclAccessPair Found = ExplicitConversions[0]; 5203 CXXConversionDecl *Conversion 5204 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 5205 5206 // The user probably meant to invoke the given explicit 5207 // conversion; use it. 5208 QualType ConvTy 5209 = Conversion->getConversionType().getNonReferenceType(); 5210 std::string TypeStr; 5211 ConvTy.getAsStringInternal(TypeStr, getPrintingPolicy()); 5212 5213 Diagnoser.diagnoseExplicitConv(*this, Loc, T, ConvTy) 5214 << FixItHint::CreateInsertion(From->getLocStart(), 5215 "static_cast<" + TypeStr + ">(") 5216 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(From->getLocEnd()), 5217 ")"); 5218 Diagnoser.noteExplicitConv(*this, Conversion, ConvTy); 5219 5220 // If we aren't in a SFINAE context, build a call to the 5221 // explicit conversion function. 5222 if (isSFINAEContext()) 5223 return ExprError(); 5224 5225 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 5226 ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion, 5227 HadMultipleCandidates); 5228 if (Result.isInvalid()) 5229 return ExprError(); 5230 // Record usage of conversion in an implicit cast. 5231 From = ImplicitCastExpr::Create(Context, Result.get()->getType(), 5232 CK_UserDefinedConversion, 5233 Result.get(), 0, 5234 Result.get()->getValueKind()); 5235 } 5236 5237 // We'll complain below about a non-integral condition type. 5238 break; 5239 5240 case 1: { 5241 // Apply this conversion. 5242 DeclAccessPair Found = ViableConversions[0]; 5243 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 5244 5245 CXXConversionDecl *Conversion 5246 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 5247 QualType ConvTy 5248 = Conversion->getConversionType().getNonReferenceType(); 5249 if (!Diagnoser.SuppressConversion) { 5250 if (isSFINAEContext()) 5251 return ExprError(); 5252 5253 Diagnoser.diagnoseConversion(*this, Loc, T, ConvTy) 5254 << From->getSourceRange(); 5255 } 5256 5257 ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion, 5258 HadMultipleCandidates); 5259 if (Result.isInvalid()) 5260 return ExprError(); 5261 // Record usage of conversion in an implicit cast. 5262 From = ImplicitCastExpr::Create(Context, Result.get()->getType(), 5263 CK_UserDefinedConversion, 5264 Result.get(), 0, 5265 Result.get()->getValueKind()); 5266 break; 5267 } 5268 5269 default: 5270 if (Diagnoser.Suppress) 5271 return ExprError(); 5272 5273 Diagnoser.diagnoseAmbiguous(*this, Loc, T) << From->getSourceRange(); 5274 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) { 5275 CXXConversionDecl *Conv 5276 = cast<CXXConversionDecl>(ViableConversions[I]->getUnderlyingDecl()); 5277 QualType ConvTy = Conv->getConversionType().getNonReferenceType(); 5278 Diagnoser.noteAmbiguous(*this, Conv, ConvTy); 5279 } 5280 return Owned(From); 5281 } 5282 5283 if (!isIntegralOrEnumerationType(From->getType(), AllowScopedEnumerations) && 5284 !Diagnoser.Suppress) { 5285 Diagnoser.diagnoseNotInt(*this, Loc, From->getType()) 5286 << From->getSourceRange(); 5287 } 5288 5289 return DefaultLvalueConversion(From); 5290 } 5291 5292 /// AddOverloadCandidate - Adds the given function to the set of 5293 /// candidate functions, using the given function call arguments. If 5294 /// @p SuppressUserConversions, then don't allow user-defined 5295 /// conversions via constructors or conversion operators. 5296 /// 5297 /// \param PartialOverloading true if we are performing "partial" overloading 5298 /// based on an incomplete set of function arguments. This feature is used by 5299 /// code completion. 5300 void 5301 Sema::AddOverloadCandidate(FunctionDecl *Function, 5302 DeclAccessPair FoundDecl, 5303 ArrayRef<Expr *> Args, 5304 OverloadCandidateSet& CandidateSet, 5305 bool SuppressUserConversions, 5306 bool PartialOverloading, 5307 bool AllowExplicit) { 5308 const FunctionProtoType* Proto 5309 = dyn_cast<FunctionProtoType>(Function->getType()->getAs<FunctionType>()); 5310 assert(Proto && "Functions without a prototype cannot be overloaded"); 5311 assert(!Function->getDescribedFunctionTemplate() && 5312 "Use AddTemplateOverloadCandidate for function templates"); 5313 5314 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { 5315 if (!isa<CXXConstructorDecl>(Method)) { 5316 // If we get here, it's because we're calling a member function 5317 // that is named without a member access expression (e.g., 5318 // "this->f") that was either written explicitly or created 5319 // implicitly. This can happen with a qualified call to a member 5320 // function, e.g., X::f(). We use an empty type for the implied 5321 // object argument (C++ [over.call.func]p3), and the acting context 5322 // is irrelevant. 5323 AddMethodCandidate(Method, FoundDecl, Method->getParent(), 5324 QualType(), Expr::Classification::makeSimpleLValue(), 5325 Args, CandidateSet, SuppressUserConversions); 5326 return; 5327 } 5328 // We treat a constructor like a non-member function, since its object 5329 // argument doesn't participate in overload resolution. 5330 } 5331 5332 if (!CandidateSet.isNewCandidate(Function)) 5333 return; 5334 5335 // Overload resolution is always an unevaluated context. 5336 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 5337 5338 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Function)){ 5339 // C++ [class.copy]p3: 5340 // A member function template is never instantiated to perform the copy 5341 // of a class object to an object of its class type. 5342 QualType ClassType = Context.getTypeDeclType(Constructor->getParent()); 5343 if (Args.size() == 1 && 5344 Constructor->isSpecializationCopyingObject() && 5345 (Context.hasSameUnqualifiedType(ClassType, Args[0]->getType()) || 5346 IsDerivedFrom(Args[0]->getType(), ClassType))) 5347 return; 5348 } 5349 5350 // Add this candidate 5351 OverloadCandidate &Candidate = CandidateSet.addCandidate(Args.size()); 5352 Candidate.FoundDecl = FoundDecl; 5353 Candidate.Function = Function; 5354 Candidate.Viable = true; 5355 Candidate.IsSurrogate = false; 5356 Candidate.IgnoreObjectArgument = false; 5357 Candidate.ExplicitCallArguments = Args.size(); 5358 5359 unsigned NumArgsInProto = Proto->getNumArgs(); 5360 5361 // (C++ 13.3.2p2): A candidate function having fewer than m 5362 // parameters is viable only if it has an ellipsis in its parameter 5363 // list (8.3.5). 5364 if ((Args.size() + (PartialOverloading && Args.size())) > NumArgsInProto && 5365 !Proto->isVariadic()) { 5366 Candidate.Viable = false; 5367 Candidate.FailureKind = ovl_fail_too_many_arguments; 5368 return; 5369 } 5370 5371 // (C++ 13.3.2p2): A candidate function having more than m parameters 5372 // is viable only if the (m+1)st parameter has a default argument 5373 // (8.3.6). For the purposes of overload resolution, the 5374 // parameter list is truncated on the right, so that there are 5375 // exactly m parameters. 5376 unsigned MinRequiredArgs = Function->getMinRequiredArguments(); 5377 if (Args.size() < MinRequiredArgs && !PartialOverloading) { 5378 // Not enough arguments. 5379 Candidate.Viable = false; 5380 Candidate.FailureKind = ovl_fail_too_few_arguments; 5381 return; 5382 } 5383 5384 // (CUDA B.1): Check for invalid calls between targets. 5385 if (getLangOpts().CUDA) 5386 if (const FunctionDecl *Caller = dyn_cast<FunctionDecl>(CurContext)) 5387 if (CheckCUDATarget(Caller, Function)) { 5388 Candidate.Viable = false; 5389 Candidate.FailureKind = ovl_fail_bad_target; 5390 return; 5391 } 5392 5393 // Determine the implicit conversion sequences for each of the 5394 // arguments. 5395 for (unsigned ArgIdx = 0; ArgIdx < Args.size(); ++ArgIdx) { 5396 if (ArgIdx < NumArgsInProto) { 5397 // (C++ 13.3.2p3): for F to be a viable function, there shall 5398 // exist for each argument an implicit conversion sequence 5399 // (13.3.3.1) that converts that argument to the corresponding 5400 // parameter of F. 5401 QualType ParamType = Proto->getArgType(ArgIdx); 5402 Candidate.Conversions[ArgIdx] 5403 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 5404 SuppressUserConversions, 5405 /*InOverloadResolution=*/true, 5406 /*AllowObjCWritebackConversion=*/ 5407 getLangOpts().ObjCAutoRefCount, 5408 AllowExplicit); 5409 if (Candidate.Conversions[ArgIdx].isBad()) { 5410 Candidate.Viable = false; 5411 Candidate.FailureKind = ovl_fail_bad_conversion; 5412 break; 5413 } 5414 } else { 5415 // (C++ 13.3.2p2): For the purposes of overload resolution, any 5416 // argument for which there is no corresponding parameter is 5417 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 5418 Candidate.Conversions[ArgIdx].setEllipsis(); 5419 } 5420 } 5421 } 5422 5423 /// \brief Add all of the function declarations in the given function set to 5424 /// the overload canddiate set. 5425 void Sema::AddFunctionCandidates(const UnresolvedSetImpl &Fns, 5426 ArrayRef<Expr *> Args, 5427 OverloadCandidateSet& CandidateSet, 5428 bool SuppressUserConversions, 5429 TemplateArgumentListInfo *ExplicitTemplateArgs) { 5430 for (UnresolvedSetIterator F = Fns.begin(), E = Fns.end(); F != E; ++F) { 5431 NamedDecl *D = F.getDecl()->getUnderlyingDecl(); 5432 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 5433 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 5434 AddMethodCandidate(cast<CXXMethodDecl>(FD), F.getPair(), 5435 cast<CXXMethodDecl>(FD)->getParent(), 5436 Args[0]->getType(), Args[0]->Classify(Context), 5437 Args.slice(1), CandidateSet, 5438 SuppressUserConversions); 5439 else 5440 AddOverloadCandidate(FD, F.getPair(), Args, CandidateSet, 5441 SuppressUserConversions); 5442 } else { 5443 FunctionTemplateDecl *FunTmpl = cast<FunctionTemplateDecl>(D); 5444 if (isa<CXXMethodDecl>(FunTmpl->getTemplatedDecl()) && 5445 !cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl())->isStatic()) 5446 AddMethodTemplateCandidate(FunTmpl, F.getPair(), 5447 cast<CXXRecordDecl>(FunTmpl->getDeclContext()), 5448 ExplicitTemplateArgs, 5449 Args[0]->getType(), 5450 Args[0]->Classify(Context), Args.slice(1), 5451 CandidateSet, SuppressUserConversions); 5452 else 5453 AddTemplateOverloadCandidate(FunTmpl, F.getPair(), 5454 ExplicitTemplateArgs, Args, 5455 CandidateSet, SuppressUserConversions); 5456 } 5457 } 5458 } 5459 5460 /// AddMethodCandidate - Adds a named decl (which is some kind of 5461 /// method) as a method candidate to the given overload set. 5462 void Sema::AddMethodCandidate(DeclAccessPair FoundDecl, 5463 QualType ObjectType, 5464 Expr::Classification ObjectClassification, 5465 Expr **Args, unsigned NumArgs, 5466 OverloadCandidateSet& CandidateSet, 5467 bool SuppressUserConversions) { 5468 NamedDecl *Decl = FoundDecl.getDecl(); 5469 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(Decl->getDeclContext()); 5470 5471 if (isa<UsingShadowDecl>(Decl)) 5472 Decl = cast<UsingShadowDecl>(Decl)->getTargetDecl(); 5473 5474 if (FunctionTemplateDecl *TD = dyn_cast<FunctionTemplateDecl>(Decl)) { 5475 assert(isa<CXXMethodDecl>(TD->getTemplatedDecl()) && 5476 "Expected a member function template"); 5477 AddMethodTemplateCandidate(TD, FoundDecl, ActingContext, 5478 /*ExplicitArgs*/ 0, 5479 ObjectType, ObjectClassification, 5480 llvm::makeArrayRef(Args, NumArgs), CandidateSet, 5481 SuppressUserConversions); 5482 } else { 5483 AddMethodCandidate(cast<CXXMethodDecl>(Decl), FoundDecl, ActingContext, 5484 ObjectType, ObjectClassification, 5485 llvm::makeArrayRef(Args, NumArgs), 5486 CandidateSet, SuppressUserConversions); 5487 } 5488 } 5489 5490 /// AddMethodCandidate - Adds the given C++ member function to the set 5491 /// of candidate functions, using the given function call arguments 5492 /// and the object argument (@c Object). For example, in a call 5493 /// @c o.f(a1,a2), @c Object will contain @c o and @c Args will contain 5494 /// both @c a1 and @c a2. If @p SuppressUserConversions, then don't 5495 /// allow user-defined conversions via constructors or conversion 5496 /// operators. 5497 void 5498 Sema::AddMethodCandidate(CXXMethodDecl *Method, DeclAccessPair FoundDecl, 5499 CXXRecordDecl *ActingContext, QualType ObjectType, 5500 Expr::Classification ObjectClassification, 5501 ArrayRef<Expr *> Args, 5502 OverloadCandidateSet& CandidateSet, 5503 bool SuppressUserConversions) { 5504 const FunctionProtoType* Proto 5505 = dyn_cast<FunctionProtoType>(Method->getType()->getAs<FunctionType>()); 5506 assert(Proto && "Methods without a prototype cannot be overloaded"); 5507 assert(!isa<CXXConstructorDecl>(Method) && 5508 "Use AddOverloadCandidate for constructors"); 5509 5510 if (!CandidateSet.isNewCandidate(Method)) 5511 return; 5512 5513 // Overload resolution is always an unevaluated context. 5514 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 5515 5516 // Add this candidate 5517 OverloadCandidate &Candidate = CandidateSet.addCandidate(Args.size() + 1); 5518 Candidate.FoundDecl = FoundDecl; 5519 Candidate.Function = Method; 5520 Candidate.IsSurrogate = false; 5521 Candidate.IgnoreObjectArgument = false; 5522 Candidate.ExplicitCallArguments = Args.size(); 5523 5524 unsigned NumArgsInProto = Proto->getNumArgs(); 5525 5526 // (C++ 13.3.2p2): A candidate function having fewer than m 5527 // parameters is viable only if it has an ellipsis in its parameter 5528 // list (8.3.5). 5529 if (Args.size() > NumArgsInProto && !Proto->isVariadic()) { 5530 Candidate.Viable = false; 5531 Candidate.FailureKind = ovl_fail_too_many_arguments; 5532 return; 5533 } 5534 5535 // (C++ 13.3.2p2): A candidate function having more than m parameters 5536 // is viable only if the (m+1)st parameter has a default argument 5537 // (8.3.6). For the purposes of overload resolution, the 5538 // parameter list is truncated on the right, so that there are 5539 // exactly m parameters. 5540 unsigned MinRequiredArgs = Method->getMinRequiredArguments(); 5541 if (Args.size() < MinRequiredArgs) { 5542 // Not enough arguments. 5543 Candidate.Viable = false; 5544 Candidate.FailureKind = ovl_fail_too_few_arguments; 5545 return; 5546 } 5547 5548 Candidate.Viable = true; 5549 5550 if (Method->isStatic() || ObjectType.isNull()) 5551 // The implicit object argument is ignored. 5552 Candidate.IgnoreObjectArgument = true; 5553 else { 5554 // Determine the implicit conversion sequence for the object 5555 // parameter. 5556 Candidate.Conversions[0] 5557 = TryObjectArgumentInitialization(*this, ObjectType, ObjectClassification, 5558 Method, ActingContext); 5559 if (Candidate.Conversions[0].isBad()) { 5560 Candidate.Viable = false; 5561 Candidate.FailureKind = ovl_fail_bad_conversion; 5562 return; 5563 } 5564 } 5565 5566 // Determine the implicit conversion sequences for each of the 5567 // arguments. 5568 for (unsigned ArgIdx = 0; ArgIdx < Args.size(); ++ArgIdx) { 5569 if (ArgIdx < NumArgsInProto) { 5570 // (C++ 13.3.2p3): for F to be a viable function, there shall 5571 // exist for each argument an implicit conversion sequence 5572 // (13.3.3.1) that converts that argument to the corresponding 5573 // parameter of F. 5574 QualType ParamType = Proto->getArgType(ArgIdx); 5575 Candidate.Conversions[ArgIdx + 1] 5576 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 5577 SuppressUserConversions, 5578 /*InOverloadResolution=*/true, 5579 /*AllowObjCWritebackConversion=*/ 5580 getLangOpts().ObjCAutoRefCount); 5581 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 5582 Candidate.Viable = false; 5583 Candidate.FailureKind = ovl_fail_bad_conversion; 5584 break; 5585 } 5586 } else { 5587 // (C++ 13.3.2p2): For the purposes of overload resolution, any 5588 // argument for which there is no corresponding parameter is 5589 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 5590 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 5591 } 5592 } 5593 } 5594 5595 /// \brief Add a C++ member function template as a candidate to the candidate 5596 /// set, using template argument deduction to produce an appropriate member 5597 /// function template specialization. 5598 void 5599 Sema::AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl, 5600 DeclAccessPair FoundDecl, 5601 CXXRecordDecl *ActingContext, 5602 TemplateArgumentListInfo *ExplicitTemplateArgs, 5603 QualType ObjectType, 5604 Expr::Classification ObjectClassification, 5605 ArrayRef<Expr *> Args, 5606 OverloadCandidateSet& CandidateSet, 5607 bool SuppressUserConversions) { 5608 if (!CandidateSet.isNewCandidate(MethodTmpl)) 5609 return; 5610 5611 // C++ [over.match.funcs]p7: 5612 // In each case where a candidate is a function template, candidate 5613 // function template specializations are generated using template argument 5614 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 5615 // candidate functions in the usual way.113) A given name can refer to one 5616 // or more function templates and also to a set of overloaded non-template 5617 // functions. In such a case, the candidate functions generated from each 5618 // function template are combined with the set of non-template candidate 5619 // functions. 5620 TemplateDeductionInfo Info(CandidateSet.getLocation()); 5621 FunctionDecl *Specialization = 0; 5622 if (TemplateDeductionResult Result 5623 = DeduceTemplateArguments(MethodTmpl, ExplicitTemplateArgs, Args, 5624 Specialization, Info)) { 5625 OverloadCandidate &Candidate = CandidateSet.addCandidate(); 5626 Candidate.FoundDecl = FoundDecl; 5627 Candidate.Function = MethodTmpl->getTemplatedDecl(); 5628 Candidate.Viable = false; 5629 Candidate.FailureKind = ovl_fail_bad_deduction; 5630 Candidate.IsSurrogate = false; 5631 Candidate.IgnoreObjectArgument = false; 5632 Candidate.ExplicitCallArguments = Args.size(); 5633 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 5634 Info); 5635 return; 5636 } 5637 5638 // Add the function template specialization produced by template argument 5639 // deduction as a candidate. 5640 assert(Specialization && "Missing member function template specialization?"); 5641 assert(isa<CXXMethodDecl>(Specialization) && 5642 "Specialization is not a member function?"); 5643 AddMethodCandidate(cast<CXXMethodDecl>(Specialization), FoundDecl, 5644 ActingContext, ObjectType, ObjectClassification, Args, 5645 CandidateSet, SuppressUserConversions); 5646 } 5647 5648 /// \brief Add a C++ function template specialization as a candidate 5649 /// in the candidate set, using template argument deduction to produce 5650 /// an appropriate function template specialization. 5651 void 5652 Sema::AddTemplateOverloadCandidate(FunctionTemplateDecl *FunctionTemplate, 5653 DeclAccessPair FoundDecl, 5654 TemplateArgumentListInfo *ExplicitTemplateArgs, 5655 ArrayRef<Expr *> Args, 5656 OverloadCandidateSet& CandidateSet, 5657 bool SuppressUserConversions) { 5658 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 5659 return; 5660 5661 // C++ [over.match.funcs]p7: 5662 // In each case where a candidate is a function template, candidate 5663 // function template specializations are generated using template argument 5664 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 5665 // candidate functions in the usual way.113) A given name can refer to one 5666 // or more function templates and also to a set of overloaded non-template 5667 // functions. In such a case, the candidate functions generated from each 5668 // function template are combined with the set of non-template candidate 5669 // functions. 5670 TemplateDeductionInfo Info(CandidateSet.getLocation()); 5671 FunctionDecl *Specialization = 0; 5672 if (TemplateDeductionResult Result 5673 = DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs, Args, 5674 Specialization, Info)) { 5675 OverloadCandidate &Candidate = CandidateSet.addCandidate(); 5676 Candidate.FoundDecl = FoundDecl; 5677 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 5678 Candidate.Viable = false; 5679 Candidate.FailureKind = ovl_fail_bad_deduction; 5680 Candidate.IsSurrogate = false; 5681 Candidate.IgnoreObjectArgument = false; 5682 Candidate.ExplicitCallArguments = Args.size(); 5683 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 5684 Info); 5685 return; 5686 } 5687 5688 // Add the function template specialization produced by template argument 5689 // deduction as a candidate. 5690 assert(Specialization && "Missing function template specialization?"); 5691 AddOverloadCandidate(Specialization, FoundDecl, Args, CandidateSet, 5692 SuppressUserConversions); 5693 } 5694 5695 /// AddConversionCandidate - Add a C++ conversion function as a 5696 /// candidate in the candidate set (C++ [over.match.conv], 5697 /// C++ [over.match.copy]). From is the expression we're converting from, 5698 /// and ToType is the type that we're eventually trying to convert to 5699 /// (which may or may not be the same type as the type that the 5700 /// conversion function produces). 5701 void 5702 Sema::AddConversionCandidate(CXXConversionDecl *Conversion, 5703 DeclAccessPair FoundDecl, 5704 CXXRecordDecl *ActingContext, 5705 Expr *From, QualType ToType, 5706 OverloadCandidateSet& CandidateSet) { 5707 assert(!Conversion->getDescribedFunctionTemplate() && 5708 "Conversion function templates use AddTemplateConversionCandidate"); 5709 QualType ConvType = Conversion->getConversionType().getNonReferenceType(); 5710 if (!CandidateSet.isNewCandidate(Conversion)) 5711 return; 5712 5713 // Overload resolution is always an unevaluated context. 5714 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 5715 5716 // Add this candidate 5717 OverloadCandidate &Candidate = CandidateSet.addCandidate(1); 5718 Candidate.FoundDecl = FoundDecl; 5719 Candidate.Function = Conversion; 5720 Candidate.IsSurrogate = false; 5721 Candidate.IgnoreObjectArgument = false; 5722 Candidate.FinalConversion.setAsIdentityConversion(); 5723 Candidate.FinalConversion.setFromType(ConvType); 5724 Candidate.FinalConversion.setAllToTypes(ToType); 5725 Candidate.Viable = true; 5726 Candidate.ExplicitCallArguments = 1; 5727 5728 // C++ [over.match.funcs]p4: 5729 // For conversion functions, the function is considered to be a member of 5730 // the class of the implicit implied object argument for the purpose of 5731 // defining the type of the implicit object parameter. 5732 // 5733 // Determine the implicit conversion sequence for the implicit 5734 // object parameter. 5735 QualType ImplicitParamType = From->getType(); 5736 if (const PointerType *FromPtrType = ImplicitParamType->getAs<PointerType>()) 5737 ImplicitParamType = FromPtrType->getPointeeType(); 5738 CXXRecordDecl *ConversionContext 5739 = cast<CXXRecordDecl>(ImplicitParamType->getAs<RecordType>()->getDecl()); 5740 5741 Candidate.Conversions[0] 5742 = TryObjectArgumentInitialization(*this, From->getType(), 5743 From->Classify(Context), 5744 Conversion, ConversionContext); 5745 5746 if (Candidate.Conversions[0].isBad()) { 5747 Candidate.Viable = false; 5748 Candidate.FailureKind = ovl_fail_bad_conversion; 5749 return; 5750 } 5751 5752 // We won't go through a user-define type conversion function to convert a 5753 // derived to base as such conversions are given Conversion Rank. They only 5754 // go through a copy constructor. 13.3.3.1.2-p4 [over.ics.user] 5755 QualType FromCanon 5756 = Context.getCanonicalType(From->getType().getUnqualifiedType()); 5757 QualType ToCanon = Context.getCanonicalType(ToType).getUnqualifiedType(); 5758 if (FromCanon == ToCanon || IsDerivedFrom(FromCanon, ToCanon)) { 5759 Candidate.Viable = false; 5760 Candidate.FailureKind = ovl_fail_trivial_conversion; 5761 return; 5762 } 5763 5764 // To determine what the conversion from the result of calling the 5765 // conversion function to the type we're eventually trying to 5766 // convert to (ToType), we need to synthesize a call to the 5767 // conversion function and attempt copy initialization from it. This 5768 // makes sure that we get the right semantics with respect to 5769 // lvalues/rvalues and the type. Fortunately, we can allocate this 5770 // call on the stack and we don't need its arguments to be 5771 // well-formed. 5772 DeclRefExpr ConversionRef(Conversion, false, Conversion->getType(), 5773 VK_LValue, From->getLocStart()); 5774 ImplicitCastExpr ConversionFn(ImplicitCastExpr::OnStack, 5775 Context.getPointerType(Conversion->getType()), 5776 CK_FunctionToPointerDecay, 5777 &ConversionRef, VK_RValue); 5778 5779 QualType ConversionType = Conversion->getConversionType(); 5780 if (RequireCompleteType(From->getLocStart(), ConversionType, 0)) { 5781 Candidate.Viable = false; 5782 Candidate.FailureKind = ovl_fail_bad_final_conversion; 5783 return; 5784 } 5785 5786 ExprValueKind VK = Expr::getValueKindForType(ConversionType); 5787 5788 // Note that it is safe to allocate CallExpr on the stack here because 5789 // there are 0 arguments (i.e., nothing is allocated using ASTContext's 5790 // allocator). 5791 QualType CallResultType = ConversionType.getNonLValueExprType(Context); 5792 CallExpr Call(Context, &ConversionFn, MultiExprArg(), CallResultType, VK, 5793 From->getLocStart()); 5794 ImplicitConversionSequence ICS = 5795 TryCopyInitialization(*this, &Call, ToType, 5796 /*SuppressUserConversions=*/true, 5797 /*InOverloadResolution=*/false, 5798 /*AllowObjCWritebackConversion=*/false); 5799 5800 switch (ICS.getKind()) { 5801 case ImplicitConversionSequence::StandardConversion: 5802 Candidate.FinalConversion = ICS.Standard; 5803 5804 // C++ [over.ics.user]p3: 5805 // If the user-defined conversion is specified by a specialization of a 5806 // conversion function template, the second standard conversion sequence 5807 // shall have exact match rank. 5808 if (Conversion->getPrimaryTemplate() && 5809 GetConversionRank(ICS.Standard.Second) != ICR_Exact_Match) { 5810 Candidate.Viable = false; 5811 Candidate.FailureKind = ovl_fail_final_conversion_not_exact; 5812 } 5813 5814 // C++0x [dcl.init.ref]p5: 5815 // In the second case, if the reference is an rvalue reference and 5816 // the second standard conversion sequence of the user-defined 5817 // conversion sequence includes an lvalue-to-rvalue conversion, the 5818 // program is ill-formed. 5819 if (ToType->isRValueReferenceType() && 5820 ICS.Standard.First == ICK_Lvalue_To_Rvalue) { 5821 Candidate.Viable = false; 5822 Candidate.FailureKind = ovl_fail_bad_final_conversion; 5823 } 5824 break; 5825 5826 case ImplicitConversionSequence::BadConversion: 5827 Candidate.Viable = false; 5828 Candidate.FailureKind = ovl_fail_bad_final_conversion; 5829 break; 5830 5831 default: 5832 llvm_unreachable( 5833 "Can only end up with a standard conversion sequence or failure"); 5834 } 5835 } 5836 5837 /// \brief Adds a conversion function template specialization 5838 /// candidate to the overload set, using template argument deduction 5839 /// to deduce the template arguments of the conversion function 5840 /// template from the type that we are converting to (C++ 5841 /// [temp.deduct.conv]). 5842 void 5843 Sema::AddTemplateConversionCandidate(FunctionTemplateDecl *FunctionTemplate, 5844 DeclAccessPair FoundDecl, 5845 CXXRecordDecl *ActingDC, 5846 Expr *From, QualType ToType, 5847 OverloadCandidateSet &CandidateSet) { 5848 assert(isa<CXXConversionDecl>(FunctionTemplate->getTemplatedDecl()) && 5849 "Only conversion function templates permitted here"); 5850 5851 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 5852 return; 5853 5854 TemplateDeductionInfo Info(CandidateSet.getLocation()); 5855 CXXConversionDecl *Specialization = 0; 5856 if (TemplateDeductionResult Result 5857 = DeduceTemplateArguments(FunctionTemplate, ToType, 5858 Specialization, Info)) { 5859 OverloadCandidate &Candidate = CandidateSet.addCandidate(); 5860 Candidate.FoundDecl = FoundDecl; 5861 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 5862 Candidate.Viable = false; 5863 Candidate.FailureKind = ovl_fail_bad_deduction; 5864 Candidate.IsSurrogate = false; 5865 Candidate.IgnoreObjectArgument = false; 5866 Candidate.ExplicitCallArguments = 1; 5867 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 5868 Info); 5869 return; 5870 } 5871 5872 // Add the conversion function template specialization produced by 5873 // template argument deduction as a candidate. 5874 assert(Specialization && "Missing function template specialization?"); 5875 AddConversionCandidate(Specialization, FoundDecl, ActingDC, From, ToType, 5876 CandidateSet); 5877 } 5878 5879 /// AddSurrogateCandidate - Adds a "surrogate" candidate function that 5880 /// converts the given @c Object to a function pointer via the 5881 /// conversion function @c Conversion, and then attempts to call it 5882 /// with the given arguments (C++ [over.call.object]p2-4). Proto is 5883 /// the type of function that we'll eventually be calling. 5884 void Sema::AddSurrogateCandidate(CXXConversionDecl *Conversion, 5885 DeclAccessPair FoundDecl, 5886 CXXRecordDecl *ActingContext, 5887 const FunctionProtoType *Proto, 5888 Expr *Object, 5889 ArrayRef<Expr *> Args, 5890 OverloadCandidateSet& CandidateSet) { 5891 if (!CandidateSet.isNewCandidate(Conversion)) 5892 return; 5893 5894 // Overload resolution is always an unevaluated context. 5895 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 5896 5897 OverloadCandidate &Candidate = CandidateSet.addCandidate(Args.size() + 1); 5898 Candidate.FoundDecl = FoundDecl; 5899 Candidate.Function = 0; 5900 Candidate.Surrogate = Conversion; 5901 Candidate.Viable = true; 5902 Candidate.IsSurrogate = true; 5903 Candidate.IgnoreObjectArgument = false; 5904 Candidate.ExplicitCallArguments = Args.size(); 5905 5906 // Determine the implicit conversion sequence for the implicit 5907 // object parameter. 5908 ImplicitConversionSequence ObjectInit 5909 = TryObjectArgumentInitialization(*this, Object->getType(), 5910 Object->Classify(Context), 5911 Conversion, ActingContext); 5912 if (ObjectInit.isBad()) { 5913 Candidate.Viable = false; 5914 Candidate.FailureKind = ovl_fail_bad_conversion; 5915 Candidate.Conversions[0] = ObjectInit; 5916 return; 5917 } 5918 5919 // The first conversion is actually a user-defined conversion whose 5920 // first conversion is ObjectInit's standard conversion (which is 5921 // effectively a reference binding). Record it as such. 5922 Candidate.Conversions[0].setUserDefined(); 5923 Candidate.Conversions[0].UserDefined.Before = ObjectInit.Standard; 5924 Candidate.Conversions[0].UserDefined.EllipsisConversion = false; 5925 Candidate.Conversions[0].UserDefined.HadMultipleCandidates = false; 5926 Candidate.Conversions[0].UserDefined.ConversionFunction = Conversion; 5927 Candidate.Conversions[0].UserDefined.FoundConversionFunction = FoundDecl; 5928 Candidate.Conversions[0].UserDefined.After 5929 = Candidate.Conversions[0].UserDefined.Before; 5930 Candidate.Conversions[0].UserDefined.After.setAsIdentityConversion(); 5931 5932 // Find the 5933 unsigned NumArgsInProto = Proto->getNumArgs(); 5934 5935 // (C++ 13.3.2p2): A candidate function having fewer than m 5936 // parameters is viable only if it has an ellipsis in its parameter 5937 // list (8.3.5). 5938 if (Args.size() > NumArgsInProto && !Proto->isVariadic()) { 5939 Candidate.Viable = false; 5940 Candidate.FailureKind = ovl_fail_too_many_arguments; 5941 return; 5942 } 5943 5944 // Function types don't have any default arguments, so just check if 5945 // we have enough arguments. 5946 if (Args.size() < NumArgsInProto) { 5947 // Not enough arguments. 5948 Candidate.Viable = false; 5949 Candidate.FailureKind = ovl_fail_too_few_arguments; 5950 return; 5951 } 5952 5953 // Determine the implicit conversion sequences for each of the 5954 // arguments. 5955 for (unsigned ArgIdx = 0; ArgIdx < Args.size(); ++ArgIdx) { 5956 if (ArgIdx < NumArgsInProto) { 5957 // (C++ 13.3.2p3): for F to be a viable function, there shall 5958 // exist for each argument an implicit conversion sequence 5959 // (13.3.3.1) that converts that argument to the corresponding 5960 // parameter of F. 5961 QualType ParamType = Proto->getArgType(ArgIdx); 5962 Candidate.Conversions[ArgIdx + 1] 5963 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 5964 /*SuppressUserConversions=*/false, 5965 /*InOverloadResolution=*/false, 5966 /*AllowObjCWritebackConversion=*/ 5967 getLangOpts().ObjCAutoRefCount); 5968 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 5969 Candidate.Viable = false; 5970 Candidate.FailureKind = ovl_fail_bad_conversion; 5971 break; 5972 } 5973 } else { 5974 // (C++ 13.3.2p2): For the purposes of overload resolution, any 5975 // argument for which there is no corresponding parameter is 5976 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 5977 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 5978 } 5979 } 5980 } 5981 5982 /// \brief Add overload candidates for overloaded operators that are 5983 /// member functions. 5984 /// 5985 /// Add the overloaded operator candidates that are member functions 5986 /// for the operator Op that was used in an operator expression such 5987 /// as "x Op y". , Args/NumArgs provides the operator arguments, and 5988 /// CandidateSet will store the added overload candidates. (C++ 5989 /// [over.match.oper]). 5990 void Sema::AddMemberOperatorCandidates(OverloadedOperatorKind Op, 5991 SourceLocation OpLoc, 5992 Expr **Args, unsigned NumArgs, 5993 OverloadCandidateSet& CandidateSet, 5994 SourceRange OpRange) { 5995 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 5996 5997 // C++ [over.match.oper]p3: 5998 // For a unary operator @ with an operand of a type whose 5999 // cv-unqualified version is T1, and for a binary operator @ with 6000 // a left operand of a type whose cv-unqualified version is T1 and 6001 // a right operand of a type whose cv-unqualified version is T2, 6002 // three sets of candidate functions, designated member 6003 // candidates, non-member candidates and built-in candidates, are 6004 // constructed as follows: 6005 QualType T1 = Args[0]->getType(); 6006 6007 // -- If T1 is a class type, the set of member candidates is the 6008 // result of the qualified lookup of T1::operator@ 6009 // (13.3.1.1.1); otherwise, the set of member candidates is 6010 // empty. 6011 if (const RecordType *T1Rec = T1->getAs<RecordType>()) { 6012 // Complete the type if it can be completed. Otherwise, we're done. 6013 if (RequireCompleteType(OpLoc, T1, 0)) 6014 return; 6015 6016 LookupResult Operators(*this, OpName, OpLoc, LookupOrdinaryName); 6017 LookupQualifiedName(Operators, T1Rec->getDecl()); 6018 Operators.suppressDiagnostics(); 6019 6020 for (LookupResult::iterator Oper = Operators.begin(), 6021 OperEnd = Operators.end(); 6022 Oper != OperEnd; 6023 ++Oper) 6024 AddMethodCandidate(Oper.getPair(), Args[0]->getType(), 6025 Args[0]->Classify(Context), Args + 1, NumArgs - 1, 6026 CandidateSet, 6027 /* SuppressUserConversions = */ false); 6028 } 6029 } 6030 6031 /// AddBuiltinCandidate - Add a candidate for a built-in 6032 /// operator. ResultTy and ParamTys are the result and parameter types 6033 /// of the built-in candidate, respectively. Args and NumArgs are the 6034 /// arguments being passed to the candidate. IsAssignmentOperator 6035 /// should be true when this built-in candidate is an assignment 6036 /// operator. NumContextualBoolArguments is the number of arguments 6037 /// (at the beginning of the argument list) that will be contextually 6038 /// converted to bool. 6039 void Sema::AddBuiltinCandidate(QualType ResultTy, QualType *ParamTys, 6040 Expr **Args, unsigned NumArgs, 6041 OverloadCandidateSet& CandidateSet, 6042 bool IsAssignmentOperator, 6043 unsigned NumContextualBoolArguments) { 6044 // Overload resolution is always an unevaluated context. 6045 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 6046 6047 // Add this candidate 6048 OverloadCandidate &Candidate = CandidateSet.addCandidate(NumArgs); 6049 Candidate.FoundDecl = DeclAccessPair::make(0, AS_none); 6050 Candidate.Function = 0; 6051 Candidate.IsSurrogate = false; 6052 Candidate.IgnoreObjectArgument = false; 6053 Candidate.BuiltinTypes.ResultTy = ResultTy; 6054 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 6055 Candidate.BuiltinTypes.ParamTypes[ArgIdx] = ParamTys[ArgIdx]; 6056 6057 // Determine the implicit conversion sequences for each of the 6058 // arguments. 6059 Candidate.Viable = true; 6060 Candidate.ExplicitCallArguments = NumArgs; 6061 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6062 // C++ [over.match.oper]p4: 6063 // For the built-in assignment operators, conversions of the 6064 // left operand are restricted as follows: 6065 // -- no temporaries are introduced to hold the left operand, and 6066 // -- no user-defined conversions are applied to the left 6067 // operand to achieve a type match with the left-most 6068 // parameter of a built-in candidate. 6069 // 6070 // We block these conversions by turning off user-defined 6071 // conversions, since that is the only way that initialization of 6072 // a reference to a non-class type can occur from something that 6073 // is not of the same type. 6074 if (ArgIdx < NumContextualBoolArguments) { 6075 assert(ParamTys[ArgIdx] == Context.BoolTy && 6076 "Contextual conversion to bool requires bool type"); 6077 Candidate.Conversions[ArgIdx] 6078 = TryContextuallyConvertToBool(*this, Args[ArgIdx]); 6079 } else { 6080 Candidate.Conversions[ArgIdx] 6081 = TryCopyInitialization(*this, Args[ArgIdx], ParamTys[ArgIdx], 6082 ArgIdx == 0 && IsAssignmentOperator, 6083 /*InOverloadResolution=*/false, 6084 /*AllowObjCWritebackConversion=*/ 6085 getLangOpts().ObjCAutoRefCount); 6086 } 6087 if (Candidate.Conversions[ArgIdx].isBad()) { 6088 Candidate.Viable = false; 6089 Candidate.FailureKind = ovl_fail_bad_conversion; 6090 break; 6091 } 6092 } 6093 } 6094 6095 /// BuiltinCandidateTypeSet - A set of types that will be used for the 6096 /// candidate operator functions for built-in operators (C++ 6097 /// [over.built]). The types are separated into pointer types and 6098 /// enumeration types. 6099 class BuiltinCandidateTypeSet { 6100 /// TypeSet - A set of types. 6101 typedef llvm::SmallPtrSet<QualType, 8> TypeSet; 6102 6103 /// PointerTypes - The set of pointer types that will be used in the 6104 /// built-in candidates. 6105 TypeSet PointerTypes; 6106 6107 /// MemberPointerTypes - The set of member pointer types that will be 6108 /// used in the built-in candidates. 6109 TypeSet MemberPointerTypes; 6110 6111 /// EnumerationTypes - The set of enumeration types that will be 6112 /// used in the built-in candidates. 6113 TypeSet EnumerationTypes; 6114 6115 /// \brief The set of vector types that will be used in the built-in 6116 /// candidates. 6117 TypeSet VectorTypes; 6118 6119 /// \brief A flag indicating non-record types are viable candidates 6120 bool HasNonRecordTypes; 6121 6122 /// \brief A flag indicating whether either arithmetic or enumeration types 6123 /// were present in the candidate set. 6124 bool HasArithmeticOrEnumeralTypes; 6125 6126 /// \brief A flag indicating whether the nullptr type was present in the 6127 /// candidate set. 6128 bool HasNullPtrType; 6129 6130 /// Sema - The semantic analysis instance where we are building the 6131 /// candidate type set. 6132 Sema &SemaRef; 6133 6134 /// Context - The AST context in which we will build the type sets. 6135 ASTContext &Context; 6136 6137 bool AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 6138 const Qualifiers &VisibleQuals); 6139 bool AddMemberPointerWithMoreQualifiedTypeVariants(QualType Ty); 6140 6141 public: 6142 /// iterator - Iterates through the types that are part of the set. 6143 typedef TypeSet::iterator iterator; 6144 6145 BuiltinCandidateTypeSet(Sema &SemaRef) 6146 : HasNonRecordTypes(false), 6147 HasArithmeticOrEnumeralTypes(false), 6148 HasNullPtrType(false), 6149 SemaRef(SemaRef), 6150 Context(SemaRef.Context) { } 6151 6152 void AddTypesConvertedFrom(QualType Ty, 6153 SourceLocation Loc, 6154 bool AllowUserConversions, 6155 bool AllowExplicitConversions, 6156 const Qualifiers &VisibleTypeConversionsQuals); 6157 6158 /// pointer_begin - First pointer type found; 6159 iterator pointer_begin() { return PointerTypes.begin(); } 6160 6161 /// pointer_end - Past the last pointer type found; 6162 iterator pointer_end() { return PointerTypes.end(); } 6163 6164 /// member_pointer_begin - First member pointer type found; 6165 iterator member_pointer_begin() { return MemberPointerTypes.begin(); } 6166 6167 /// member_pointer_end - Past the last member pointer type found; 6168 iterator member_pointer_end() { return MemberPointerTypes.end(); } 6169 6170 /// enumeration_begin - First enumeration type found; 6171 iterator enumeration_begin() { return EnumerationTypes.begin(); } 6172 6173 /// enumeration_end - Past the last enumeration type found; 6174 iterator enumeration_end() { return EnumerationTypes.end(); } 6175 6176 iterator vector_begin() { return VectorTypes.begin(); } 6177 iterator vector_end() { return VectorTypes.end(); } 6178 6179 bool hasNonRecordTypes() { return HasNonRecordTypes; } 6180 bool hasArithmeticOrEnumeralTypes() { return HasArithmeticOrEnumeralTypes; } 6181 bool hasNullPtrType() const { return HasNullPtrType; } 6182 }; 6183 6184 /// AddPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty to 6185 /// the set of pointer types along with any more-qualified variants of 6186 /// that type. For example, if @p Ty is "int const *", this routine 6187 /// will add "int const *", "int const volatile *", "int const 6188 /// restrict *", and "int const volatile restrict *" to the set of 6189 /// pointer types. Returns true if the add of @p Ty itself succeeded, 6190 /// false otherwise. 6191 /// 6192 /// FIXME: what to do about extended qualifiers? 6193 bool 6194 BuiltinCandidateTypeSet::AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 6195 const Qualifiers &VisibleQuals) { 6196 6197 // Insert this type. 6198 if (!PointerTypes.insert(Ty)) 6199 return false; 6200 6201 QualType PointeeTy; 6202 const PointerType *PointerTy = Ty->getAs<PointerType>(); 6203 bool buildObjCPtr = false; 6204 if (!PointerTy) { 6205 const ObjCObjectPointerType *PTy = Ty->castAs<ObjCObjectPointerType>(); 6206 PointeeTy = PTy->getPointeeType(); 6207 buildObjCPtr = true; 6208 } else { 6209 PointeeTy = PointerTy->getPointeeType(); 6210 } 6211 6212 // Don't add qualified variants of arrays. For one, they're not allowed 6213 // (the qualifier would sink to the element type), and for another, the 6214 // only overload situation where it matters is subscript or pointer +- int, 6215 // and those shouldn't have qualifier variants anyway. 6216 if (PointeeTy->isArrayType()) 6217 return true; 6218 6219 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 6220 bool hasVolatile = VisibleQuals.hasVolatile(); 6221 bool hasRestrict = VisibleQuals.hasRestrict(); 6222 6223 // Iterate through all strict supersets of BaseCVR. 6224 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 6225 if ((CVR | BaseCVR) != CVR) continue; 6226 // Skip over volatile if no volatile found anywhere in the types. 6227 if ((CVR & Qualifiers::Volatile) && !hasVolatile) continue; 6228 6229 // Skip over restrict if no restrict found anywhere in the types, or if 6230 // the type cannot be restrict-qualified. 6231 if ((CVR & Qualifiers::Restrict) && 6232 (!hasRestrict || 6233 (!(PointeeTy->isAnyPointerType() || PointeeTy->isReferenceType())))) 6234 continue; 6235 6236 // Build qualified pointee type. 6237 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 6238 6239 // Build qualified pointer type. 6240 QualType QPointerTy; 6241 if (!buildObjCPtr) 6242 QPointerTy = Context.getPointerType(QPointeeTy); 6243 else 6244 QPointerTy = Context.getObjCObjectPointerType(QPointeeTy); 6245 6246 // Insert qualified pointer type. 6247 PointerTypes.insert(QPointerTy); 6248 } 6249 6250 return true; 6251 } 6252 6253 /// AddMemberPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty 6254 /// to the set of pointer types along with any more-qualified variants of 6255 /// that type. For example, if @p Ty is "int const *", this routine 6256 /// will add "int const *", "int const volatile *", "int const 6257 /// restrict *", and "int const volatile restrict *" to the set of 6258 /// pointer types. Returns true if the add of @p Ty itself succeeded, 6259 /// false otherwise. 6260 /// 6261 /// FIXME: what to do about extended qualifiers? 6262 bool 6263 BuiltinCandidateTypeSet::AddMemberPointerWithMoreQualifiedTypeVariants( 6264 QualType Ty) { 6265 // Insert this type. 6266 if (!MemberPointerTypes.insert(Ty)) 6267 return false; 6268 6269 const MemberPointerType *PointerTy = Ty->getAs<MemberPointerType>(); 6270 assert(PointerTy && "type was not a member pointer type!"); 6271 6272 QualType PointeeTy = PointerTy->getPointeeType(); 6273 // Don't add qualified variants of arrays. For one, they're not allowed 6274 // (the qualifier would sink to the element type), and for another, the 6275 // only overload situation where it matters is subscript or pointer +- int, 6276 // and those shouldn't have qualifier variants anyway. 6277 if (PointeeTy->isArrayType()) 6278 return true; 6279 const Type *ClassTy = PointerTy->getClass(); 6280 6281 // Iterate through all strict supersets of the pointee type's CVR 6282 // qualifiers. 6283 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 6284 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 6285 if ((CVR | BaseCVR) != CVR) continue; 6286 6287 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 6288 MemberPointerTypes.insert( 6289 Context.getMemberPointerType(QPointeeTy, ClassTy)); 6290 } 6291 6292 return true; 6293 } 6294 6295 /// AddTypesConvertedFrom - Add each of the types to which the type @p 6296 /// Ty can be implicit converted to the given set of @p Types. We're 6297 /// primarily interested in pointer types and enumeration types. We also 6298 /// take member pointer types, for the conditional operator. 6299 /// AllowUserConversions is true if we should look at the conversion 6300 /// functions of a class type, and AllowExplicitConversions if we 6301 /// should also include the explicit conversion functions of a class 6302 /// type. 6303 void 6304 BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty, 6305 SourceLocation Loc, 6306 bool AllowUserConversions, 6307 bool AllowExplicitConversions, 6308 const Qualifiers &VisibleQuals) { 6309 // Only deal with canonical types. 6310 Ty = Context.getCanonicalType(Ty); 6311 6312 // Look through reference types; they aren't part of the type of an 6313 // expression for the purposes of conversions. 6314 if (const ReferenceType *RefTy = Ty->getAs<ReferenceType>()) 6315 Ty = RefTy->getPointeeType(); 6316 6317 // If we're dealing with an array type, decay to the pointer. 6318 if (Ty->isArrayType()) 6319 Ty = SemaRef.Context.getArrayDecayedType(Ty); 6320 6321 // Otherwise, we don't care about qualifiers on the type. 6322 Ty = Ty.getLocalUnqualifiedType(); 6323 6324 // Flag if we ever add a non-record type. 6325 const RecordType *TyRec = Ty->getAs<RecordType>(); 6326 HasNonRecordTypes = HasNonRecordTypes || !TyRec; 6327 6328 // Flag if we encounter an arithmetic type. 6329 HasArithmeticOrEnumeralTypes = 6330 HasArithmeticOrEnumeralTypes || Ty->isArithmeticType(); 6331 6332 if (Ty->isObjCIdType() || Ty->isObjCClassType()) 6333 PointerTypes.insert(Ty); 6334 else if (Ty->getAs<PointerType>() || Ty->getAs<ObjCObjectPointerType>()) { 6335 // Insert our type, and its more-qualified variants, into the set 6336 // of types. 6337 if (!AddPointerWithMoreQualifiedTypeVariants(Ty, VisibleQuals)) 6338 return; 6339 } else if (Ty->isMemberPointerType()) { 6340 // Member pointers are far easier, since the pointee can't be converted. 6341 if (!AddMemberPointerWithMoreQualifiedTypeVariants(Ty)) 6342 return; 6343 } else if (Ty->isEnumeralType()) { 6344 HasArithmeticOrEnumeralTypes = true; 6345 EnumerationTypes.insert(Ty); 6346 } else if (Ty->isVectorType()) { 6347 // We treat vector types as arithmetic types in many contexts as an 6348 // extension. 6349 HasArithmeticOrEnumeralTypes = true; 6350 VectorTypes.insert(Ty); 6351 } else if (Ty->isNullPtrType()) { 6352 HasNullPtrType = true; 6353 } else if (AllowUserConversions && TyRec) { 6354 // No conversion functions in incomplete types. 6355 if (SemaRef.RequireCompleteType(Loc, Ty, 0)) 6356 return; 6357 6358 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 6359 std::pair<CXXRecordDecl::conversion_iterator, 6360 CXXRecordDecl::conversion_iterator> 6361 Conversions = ClassDecl->getVisibleConversionFunctions(); 6362 for (CXXRecordDecl::conversion_iterator 6363 I = Conversions.first, E = Conversions.second; I != E; ++I) { 6364 NamedDecl *D = I.getDecl(); 6365 if (isa<UsingShadowDecl>(D)) 6366 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 6367 6368 // Skip conversion function templates; they don't tell us anything 6369 // about which builtin types we can convert to. 6370 if (isa<FunctionTemplateDecl>(D)) 6371 continue; 6372 6373 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 6374 if (AllowExplicitConversions || !Conv->isExplicit()) { 6375 AddTypesConvertedFrom(Conv->getConversionType(), Loc, false, false, 6376 VisibleQuals); 6377 } 6378 } 6379 } 6380 } 6381 6382 /// \brief Helper function for AddBuiltinOperatorCandidates() that adds 6383 /// the volatile- and non-volatile-qualified assignment operators for the 6384 /// given type to the candidate set. 6385 static void AddBuiltinAssignmentOperatorCandidates(Sema &S, 6386 QualType T, 6387 Expr **Args, 6388 unsigned NumArgs, 6389 OverloadCandidateSet &CandidateSet) { 6390 QualType ParamTypes[2]; 6391 6392 // T& operator=(T&, T) 6393 ParamTypes[0] = S.Context.getLValueReferenceType(T); 6394 ParamTypes[1] = T; 6395 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 6396 /*IsAssignmentOperator=*/true); 6397 6398 if (!S.Context.getCanonicalType(T).isVolatileQualified()) { 6399 // volatile T& operator=(volatile T&, T) 6400 ParamTypes[0] 6401 = S.Context.getLValueReferenceType(S.Context.getVolatileType(T)); 6402 ParamTypes[1] = T; 6403 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 6404 /*IsAssignmentOperator=*/true); 6405 } 6406 } 6407 6408 /// CollectVRQualifiers - This routine returns Volatile/Restrict qualifiers, 6409 /// if any, found in visible type conversion functions found in ArgExpr's type. 6410 static Qualifiers CollectVRQualifiers(ASTContext &Context, Expr* ArgExpr) { 6411 Qualifiers VRQuals; 6412 const RecordType *TyRec; 6413 if (const MemberPointerType *RHSMPType = 6414 ArgExpr->getType()->getAs<MemberPointerType>()) 6415 TyRec = RHSMPType->getClass()->getAs<RecordType>(); 6416 else 6417 TyRec = ArgExpr->getType()->getAs<RecordType>(); 6418 if (!TyRec) { 6419 // Just to be safe, assume the worst case. 6420 VRQuals.addVolatile(); 6421 VRQuals.addRestrict(); 6422 return VRQuals; 6423 } 6424 6425 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 6426 if (!ClassDecl->hasDefinition()) 6427 return VRQuals; 6428 6429 std::pair<CXXRecordDecl::conversion_iterator, 6430 CXXRecordDecl::conversion_iterator> 6431 Conversions = ClassDecl->getVisibleConversionFunctions(); 6432 6433 for (CXXRecordDecl::conversion_iterator 6434 I = Conversions.first, E = Conversions.second; I != E; ++I) { 6435 NamedDecl *D = I.getDecl(); 6436 if (isa<UsingShadowDecl>(D)) 6437 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 6438 if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(D)) { 6439 QualType CanTy = Context.getCanonicalType(Conv->getConversionType()); 6440 if (const ReferenceType *ResTypeRef = CanTy->getAs<ReferenceType>()) 6441 CanTy = ResTypeRef->getPointeeType(); 6442 // Need to go down the pointer/mempointer chain and add qualifiers 6443 // as see them. 6444 bool done = false; 6445 while (!done) { 6446 if (CanTy.isRestrictQualified()) 6447 VRQuals.addRestrict(); 6448 if (const PointerType *ResTypePtr = CanTy->getAs<PointerType>()) 6449 CanTy = ResTypePtr->getPointeeType(); 6450 else if (const MemberPointerType *ResTypeMPtr = 6451 CanTy->getAs<MemberPointerType>()) 6452 CanTy = ResTypeMPtr->getPointeeType(); 6453 else 6454 done = true; 6455 if (CanTy.isVolatileQualified()) 6456 VRQuals.addVolatile(); 6457 if (VRQuals.hasRestrict() && VRQuals.hasVolatile()) 6458 return VRQuals; 6459 } 6460 } 6461 } 6462 return VRQuals; 6463 } 6464 6465 namespace { 6466 6467 /// \brief Helper class to manage the addition of builtin operator overload 6468 /// candidates. It provides shared state and utility methods used throughout 6469 /// the process, as well as a helper method to add each group of builtin 6470 /// operator overloads from the standard to a candidate set. 6471 class BuiltinOperatorOverloadBuilder { 6472 // Common instance state available to all overload candidate addition methods. 6473 Sema &S; 6474 Expr **Args; 6475 unsigned NumArgs; 6476 Qualifiers VisibleTypeConversionsQuals; 6477 bool HasArithmeticOrEnumeralCandidateType; 6478 SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes; 6479 OverloadCandidateSet &CandidateSet; 6480 6481 // Define some constants used to index and iterate over the arithemetic types 6482 // provided via the getArithmeticType() method below. 6483 // The "promoted arithmetic types" are the arithmetic 6484 // types are that preserved by promotion (C++ [over.built]p2). 6485 static const unsigned FirstIntegralType = 3; 6486 static const unsigned LastIntegralType = 20; 6487 static const unsigned FirstPromotedIntegralType = 3, 6488 LastPromotedIntegralType = 11; 6489 static const unsigned FirstPromotedArithmeticType = 0, 6490 LastPromotedArithmeticType = 11; 6491 static const unsigned NumArithmeticTypes = 20; 6492 6493 /// \brief Get the canonical type for a given arithmetic type index. 6494 CanQualType getArithmeticType(unsigned index) { 6495 assert(index < NumArithmeticTypes); 6496 static CanQualType ASTContext::* const 6497 ArithmeticTypes[NumArithmeticTypes] = { 6498 // Start of promoted types. 6499 &ASTContext::FloatTy, 6500 &ASTContext::DoubleTy, 6501 &ASTContext::LongDoubleTy, 6502 6503 // Start of integral types. 6504 &ASTContext::IntTy, 6505 &ASTContext::LongTy, 6506 &ASTContext::LongLongTy, 6507 &ASTContext::Int128Ty, 6508 &ASTContext::UnsignedIntTy, 6509 &ASTContext::UnsignedLongTy, 6510 &ASTContext::UnsignedLongLongTy, 6511 &ASTContext::UnsignedInt128Ty, 6512 // End of promoted types. 6513 6514 &ASTContext::BoolTy, 6515 &ASTContext::CharTy, 6516 &ASTContext::WCharTy, 6517 &ASTContext::Char16Ty, 6518 &ASTContext::Char32Ty, 6519 &ASTContext::SignedCharTy, 6520 &ASTContext::ShortTy, 6521 &ASTContext::UnsignedCharTy, 6522 &ASTContext::UnsignedShortTy, 6523 // End of integral types. 6524 // FIXME: What about complex? What about half? 6525 }; 6526 return S.Context.*ArithmeticTypes[index]; 6527 } 6528 6529 /// \brief Gets the canonical type resulting from the usual arithemetic 6530 /// converions for the given arithmetic types. 6531 CanQualType getUsualArithmeticConversions(unsigned L, unsigned R) { 6532 // Accelerator table for performing the usual arithmetic conversions. 6533 // The rules are basically: 6534 // - if either is floating-point, use the wider floating-point 6535 // - if same signedness, use the higher rank 6536 // - if same size, use unsigned of the higher rank 6537 // - use the larger type 6538 // These rules, together with the axiom that higher ranks are 6539 // never smaller, are sufficient to precompute all of these results 6540 // *except* when dealing with signed types of higher rank. 6541 // (we could precompute SLL x UI for all known platforms, but it's 6542 // better not to make any assumptions). 6543 // We assume that int128 has a higher rank than long long on all platforms. 6544 enum PromotedType { 6545 Dep=-1, 6546 Flt, Dbl, LDbl, SI, SL, SLL, S128, UI, UL, ULL, U128 6547 }; 6548 static const PromotedType ConversionsTable[LastPromotedArithmeticType] 6549 [LastPromotedArithmeticType] = { 6550 /* Flt*/ { Flt, Dbl, LDbl, Flt, Flt, Flt, Flt, Flt, Flt, Flt, Flt }, 6551 /* Dbl*/ { Dbl, Dbl, LDbl, Dbl, Dbl, Dbl, Dbl, Dbl, Dbl, Dbl, Dbl }, 6552 /*LDbl*/ { LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl }, 6553 /* SI*/ { Flt, Dbl, LDbl, SI, SL, SLL, S128, UI, UL, ULL, U128 }, 6554 /* SL*/ { Flt, Dbl, LDbl, SL, SL, SLL, S128, Dep, UL, ULL, U128 }, 6555 /* SLL*/ { Flt, Dbl, LDbl, SLL, SLL, SLL, S128, Dep, Dep, ULL, U128 }, 6556 /*S128*/ { Flt, Dbl, LDbl, S128, S128, S128, S128, S128, S128, S128, U128 }, 6557 /* UI*/ { Flt, Dbl, LDbl, UI, Dep, Dep, S128, UI, UL, ULL, U128 }, 6558 /* UL*/ { Flt, Dbl, LDbl, UL, UL, Dep, S128, UL, UL, ULL, U128 }, 6559 /* ULL*/ { Flt, Dbl, LDbl, ULL, ULL, ULL, S128, ULL, ULL, ULL, U128 }, 6560 /*U128*/ { Flt, Dbl, LDbl, U128, U128, U128, U128, U128, U128, U128, U128 }, 6561 }; 6562 6563 assert(L < LastPromotedArithmeticType); 6564 assert(R < LastPromotedArithmeticType); 6565 int Idx = ConversionsTable[L][R]; 6566 6567 // Fast path: the table gives us a concrete answer. 6568 if (Idx != Dep) return getArithmeticType(Idx); 6569 6570 // Slow path: we need to compare widths. 6571 // An invariant is that the signed type has higher rank. 6572 CanQualType LT = getArithmeticType(L), 6573 RT = getArithmeticType(R); 6574 unsigned LW = S.Context.getIntWidth(LT), 6575 RW = S.Context.getIntWidth(RT); 6576 6577 // If they're different widths, use the signed type. 6578 if (LW > RW) return LT; 6579 else if (LW < RW) return RT; 6580 6581 // Otherwise, use the unsigned type of the signed type's rank. 6582 if (L == SL || R == SL) return S.Context.UnsignedLongTy; 6583 assert(L == SLL || R == SLL); 6584 return S.Context.UnsignedLongLongTy; 6585 } 6586 6587 /// \brief Helper method to factor out the common pattern of adding overloads 6588 /// for '++' and '--' builtin operators. 6589 void addPlusPlusMinusMinusStyleOverloads(QualType CandidateTy, 6590 bool HasVolatile, 6591 bool HasRestrict) { 6592 QualType ParamTypes[2] = { 6593 S.Context.getLValueReferenceType(CandidateTy), 6594 S.Context.IntTy 6595 }; 6596 6597 // Non-volatile version. 6598 if (NumArgs == 1) 6599 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 6600 else 6601 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 6602 6603 // Use a heuristic to reduce number of builtin candidates in the set: 6604 // add volatile version only if there are conversions to a volatile type. 6605 if (HasVolatile) { 6606 ParamTypes[0] = 6607 S.Context.getLValueReferenceType( 6608 S.Context.getVolatileType(CandidateTy)); 6609 if (NumArgs == 1) 6610 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 6611 else 6612 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 6613 } 6614 6615 // Add restrict version only if there are conversions to a restrict type 6616 // and our candidate type is a non-restrict-qualified pointer. 6617 if (HasRestrict && CandidateTy->isAnyPointerType() && 6618 !CandidateTy.isRestrictQualified()) { 6619 ParamTypes[0] 6620 = S.Context.getLValueReferenceType( 6621 S.Context.getCVRQualifiedType(CandidateTy, Qualifiers::Restrict)); 6622 if (NumArgs == 1) 6623 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 6624 else 6625 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 6626 6627 if (HasVolatile) { 6628 ParamTypes[0] 6629 = S.Context.getLValueReferenceType( 6630 S.Context.getCVRQualifiedType(CandidateTy, 6631 (Qualifiers::Volatile | 6632 Qualifiers::Restrict))); 6633 if (NumArgs == 1) 6634 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, 6635 CandidateSet); 6636 else 6637 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 6638 } 6639 } 6640 6641 } 6642 6643 public: 6644 BuiltinOperatorOverloadBuilder( 6645 Sema &S, Expr **Args, unsigned NumArgs, 6646 Qualifiers VisibleTypeConversionsQuals, 6647 bool HasArithmeticOrEnumeralCandidateType, 6648 SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes, 6649 OverloadCandidateSet &CandidateSet) 6650 : S(S), Args(Args), NumArgs(NumArgs), 6651 VisibleTypeConversionsQuals(VisibleTypeConversionsQuals), 6652 HasArithmeticOrEnumeralCandidateType( 6653 HasArithmeticOrEnumeralCandidateType), 6654 CandidateTypes(CandidateTypes), 6655 CandidateSet(CandidateSet) { 6656 // Validate some of our static helper constants in debug builds. 6657 assert(getArithmeticType(FirstPromotedIntegralType) == S.Context.IntTy && 6658 "Invalid first promoted integral type"); 6659 assert(getArithmeticType(LastPromotedIntegralType - 1) 6660 == S.Context.UnsignedInt128Ty && 6661 "Invalid last promoted integral type"); 6662 assert(getArithmeticType(FirstPromotedArithmeticType) 6663 == S.Context.FloatTy && 6664 "Invalid first promoted arithmetic type"); 6665 assert(getArithmeticType(LastPromotedArithmeticType - 1) 6666 == S.Context.UnsignedInt128Ty && 6667 "Invalid last promoted arithmetic type"); 6668 } 6669 6670 // C++ [over.built]p3: 6671 // 6672 // For every pair (T, VQ), where T is an arithmetic type, and VQ 6673 // is either volatile or empty, there exist candidate operator 6674 // functions of the form 6675 // 6676 // VQ T& operator++(VQ T&); 6677 // T operator++(VQ T&, int); 6678 // 6679 // C++ [over.built]p4: 6680 // 6681 // For every pair (T, VQ), where T is an arithmetic type other 6682 // than bool, and VQ is either volatile or empty, there exist 6683 // candidate operator functions of the form 6684 // 6685 // VQ T& operator--(VQ T&); 6686 // T operator--(VQ T&, int); 6687 void addPlusPlusMinusMinusArithmeticOverloads(OverloadedOperatorKind Op) { 6688 if (!HasArithmeticOrEnumeralCandidateType) 6689 return; 6690 6691 for (unsigned Arith = (Op == OO_PlusPlus? 0 : 1); 6692 Arith < NumArithmeticTypes; ++Arith) { 6693 addPlusPlusMinusMinusStyleOverloads( 6694 getArithmeticType(Arith), 6695 VisibleTypeConversionsQuals.hasVolatile(), 6696 VisibleTypeConversionsQuals.hasRestrict()); 6697 } 6698 } 6699 6700 // C++ [over.built]p5: 6701 // 6702 // For every pair (T, VQ), where T is a cv-qualified or 6703 // cv-unqualified object type, and VQ is either volatile or 6704 // empty, there exist candidate operator functions of the form 6705 // 6706 // T*VQ& operator++(T*VQ&); 6707 // T*VQ& operator--(T*VQ&); 6708 // T* operator++(T*VQ&, int); 6709 // T* operator--(T*VQ&, int); 6710 void addPlusPlusMinusMinusPointerOverloads() { 6711 for (BuiltinCandidateTypeSet::iterator 6712 Ptr = CandidateTypes[0].pointer_begin(), 6713 PtrEnd = CandidateTypes[0].pointer_end(); 6714 Ptr != PtrEnd; ++Ptr) { 6715 // Skip pointer types that aren't pointers to object types. 6716 if (!(*Ptr)->getPointeeType()->isObjectType()) 6717 continue; 6718 6719 addPlusPlusMinusMinusStyleOverloads(*Ptr, 6720 (!(*Ptr).isVolatileQualified() && 6721 VisibleTypeConversionsQuals.hasVolatile()), 6722 (!(*Ptr).isRestrictQualified() && 6723 VisibleTypeConversionsQuals.hasRestrict())); 6724 } 6725 } 6726 6727 // C++ [over.built]p6: 6728 // For every cv-qualified or cv-unqualified object type T, there 6729 // exist candidate operator functions of the form 6730 // 6731 // T& operator*(T*); 6732 // 6733 // C++ [over.built]p7: 6734 // For every function type T that does not have cv-qualifiers or a 6735 // ref-qualifier, there exist candidate operator functions of the form 6736 // T& operator*(T*); 6737 void addUnaryStarPointerOverloads() { 6738 for (BuiltinCandidateTypeSet::iterator 6739 Ptr = CandidateTypes[0].pointer_begin(), 6740 PtrEnd = CandidateTypes[0].pointer_end(); 6741 Ptr != PtrEnd; ++Ptr) { 6742 QualType ParamTy = *Ptr; 6743 QualType PointeeTy = ParamTy->getPointeeType(); 6744 if (!PointeeTy->isObjectType() && !PointeeTy->isFunctionType()) 6745 continue; 6746 6747 if (const FunctionProtoType *Proto =PointeeTy->getAs<FunctionProtoType>()) 6748 if (Proto->getTypeQuals() || Proto->getRefQualifier()) 6749 continue; 6750 6751 S.AddBuiltinCandidate(S.Context.getLValueReferenceType(PointeeTy), 6752 &ParamTy, Args, 1, CandidateSet); 6753 } 6754 } 6755 6756 // C++ [over.built]p9: 6757 // For every promoted arithmetic type T, there exist candidate 6758 // operator functions of the form 6759 // 6760 // T operator+(T); 6761 // T operator-(T); 6762 void addUnaryPlusOrMinusArithmeticOverloads() { 6763 if (!HasArithmeticOrEnumeralCandidateType) 6764 return; 6765 6766 for (unsigned Arith = FirstPromotedArithmeticType; 6767 Arith < LastPromotedArithmeticType; ++Arith) { 6768 QualType ArithTy = getArithmeticType(Arith); 6769 S.AddBuiltinCandidate(ArithTy, &ArithTy, Args, 1, CandidateSet); 6770 } 6771 6772 // Extension: We also add these operators for vector types. 6773 for (BuiltinCandidateTypeSet::iterator 6774 Vec = CandidateTypes[0].vector_begin(), 6775 VecEnd = CandidateTypes[0].vector_end(); 6776 Vec != VecEnd; ++Vec) { 6777 QualType VecTy = *Vec; 6778 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 6779 } 6780 } 6781 6782 // C++ [over.built]p8: 6783 // For every type T, there exist candidate operator functions of 6784 // the form 6785 // 6786 // T* operator+(T*); 6787 void addUnaryPlusPointerOverloads() { 6788 for (BuiltinCandidateTypeSet::iterator 6789 Ptr = CandidateTypes[0].pointer_begin(), 6790 PtrEnd = CandidateTypes[0].pointer_end(); 6791 Ptr != PtrEnd; ++Ptr) { 6792 QualType ParamTy = *Ptr; 6793 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet); 6794 } 6795 } 6796 6797 // C++ [over.built]p10: 6798 // For every promoted integral type T, there exist candidate 6799 // operator functions of the form 6800 // 6801 // T operator~(T); 6802 void addUnaryTildePromotedIntegralOverloads() { 6803 if (!HasArithmeticOrEnumeralCandidateType) 6804 return; 6805 6806 for (unsigned Int = FirstPromotedIntegralType; 6807 Int < LastPromotedIntegralType; ++Int) { 6808 QualType IntTy = getArithmeticType(Int); 6809 S.AddBuiltinCandidate(IntTy, &IntTy, Args, 1, CandidateSet); 6810 } 6811 6812 // Extension: We also add this operator for vector types. 6813 for (BuiltinCandidateTypeSet::iterator 6814 Vec = CandidateTypes[0].vector_begin(), 6815 VecEnd = CandidateTypes[0].vector_end(); 6816 Vec != VecEnd; ++Vec) { 6817 QualType VecTy = *Vec; 6818 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 6819 } 6820 } 6821 6822 // C++ [over.match.oper]p16: 6823 // For every pointer to member type T, there exist candidate operator 6824 // functions of the form 6825 // 6826 // bool operator==(T,T); 6827 // bool operator!=(T,T); 6828 void addEqualEqualOrNotEqualMemberPointerOverloads() { 6829 /// Set of (canonical) types that we've already handled. 6830 llvm::SmallPtrSet<QualType, 8> AddedTypes; 6831 6832 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6833 for (BuiltinCandidateTypeSet::iterator 6834 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 6835 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 6836 MemPtr != MemPtrEnd; 6837 ++MemPtr) { 6838 // Don't add the same builtin candidate twice. 6839 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 6840 continue; 6841 6842 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 6843 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 6844 CandidateSet); 6845 } 6846 } 6847 } 6848 6849 // C++ [over.built]p15: 6850 // 6851 // For every T, where T is an enumeration type, a pointer type, or 6852 // std::nullptr_t, there exist candidate operator functions of the form 6853 // 6854 // bool operator<(T, T); 6855 // bool operator>(T, T); 6856 // bool operator<=(T, T); 6857 // bool operator>=(T, T); 6858 // bool operator==(T, T); 6859 // bool operator!=(T, T); 6860 void addRelationalPointerOrEnumeralOverloads() { 6861 // C++ [over.match.oper]p3: 6862 // [...]the built-in candidates include all of the candidate operator 6863 // functions defined in 13.6 that, compared to the given operator, [...] 6864 // do not have the same parameter-type-list as any non-template non-member 6865 // candidate. 6866 // 6867 // Note that in practice, this only affects enumeration types because there 6868 // aren't any built-in candidates of record type, and a user-defined operator 6869 // must have an operand of record or enumeration type. Also, the only other 6870 // overloaded operator with enumeration arguments, operator=, 6871 // cannot be overloaded for enumeration types, so this is the only place 6872 // where we must suppress candidates like this. 6873 llvm::DenseSet<std::pair<CanQualType, CanQualType> > 6874 UserDefinedBinaryOperators; 6875 6876 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6877 if (CandidateTypes[ArgIdx].enumeration_begin() != 6878 CandidateTypes[ArgIdx].enumeration_end()) { 6879 for (OverloadCandidateSet::iterator C = CandidateSet.begin(), 6880 CEnd = CandidateSet.end(); 6881 C != CEnd; ++C) { 6882 if (!C->Viable || !C->Function || C->Function->getNumParams() != 2) 6883 continue; 6884 6885 if (C->Function->isFunctionTemplateSpecialization()) 6886 continue; 6887 6888 QualType FirstParamType = 6889 C->Function->getParamDecl(0)->getType().getUnqualifiedType(); 6890 QualType SecondParamType = 6891 C->Function->getParamDecl(1)->getType().getUnqualifiedType(); 6892 6893 // Skip if either parameter isn't of enumeral type. 6894 if (!FirstParamType->isEnumeralType() || 6895 !SecondParamType->isEnumeralType()) 6896 continue; 6897 6898 // Add this operator to the set of known user-defined operators. 6899 UserDefinedBinaryOperators.insert( 6900 std::make_pair(S.Context.getCanonicalType(FirstParamType), 6901 S.Context.getCanonicalType(SecondParamType))); 6902 } 6903 } 6904 } 6905 6906 /// Set of (canonical) types that we've already handled. 6907 llvm::SmallPtrSet<QualType, 8> AddedTypes; 6908 6909 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6910 for (BuiltinCandidateTypeSet::iterator 6911 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 6912 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 6913 Ptr != PtrEnd; ++Ptr) { 6914 // Don't add the same builtin candidate twice. 6915 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 6916 continue; 6917 6918 QualType ParamTypes[2] = { *Ptr, *Ptr }; 6919 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 6920 CandidateSet); 6921 } 6922 for (BuiltinCandidateTypeSet::iterator 6923 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 6924 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 6925 Enum != EnumEnd; ++Enum) { 6926 CanQualType CanonType = S.Context.getCanonicalType(*Enum); 6927 6928 // Don't add the same builtin candidate twice, or if a user defined 6929 // candidate exists. 6930 if (!AddedTypes.insert(CanonType) || 6931 UserDefinedBinaryOperators.count(std::make_pair(CanonType, 6932 CanonType))) 6933 continue; 6934 6935 QualType ParamTypes[2] = { *Enum, *Enum }; 6936 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 6937 CandidateSet); 6938 } 6939 6940 if (CandidateTypes[ArgIdx].hasNullPtrType()) { 6941 CanQualType NullPtrTy = S.Context.getCanonicalType(S.Context.NullPtrTy); 6942 if (AddedTypes.insert(NullPtrTy) && 6943 !UserDefinedBinaryOperators.count(std::make_pair(NullPtrTy, 6944 NullPtrTy))) { 6945 QualType ParamTypes[2] = { NullPtrTy, NullPtrTy }; 6946 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 6947 CandidateSet); 6948 } 6949 } 6950 } 6951 } 6952 6953 // C++ [over.built]p13: 6954 // 6955 // For every cv-qualified or cv-unqualified object type T 6956 // there exist candidate operator functions of the form 6957 // 6958 // T* operator+(T*, ptrdiff_t); 6959 // T& operator[](T*, ptrdiff_t); [BELOW] 6960 // T* operator-(T*, ptrdiff_t); 6961 // T* operator+(ptrdiff_t, T*); 6962 // T& operator[](ptrdiff_t, T*); [BELOW] 6963 // 6964 // C++ [over.built]p14: 6965 // 6966 // For every T, where T is a pointer to object type, there 6967 // exist candidate operator functions of the form 6968 // 6969 // ptrdiff_t operator-(T, T); 6970 void addBinaryPlusOrMinusPointerOverloads(OverloadedOperatorKind Op) { 6971 /// Set of (canonical) types that we've already handled. 6972 llvm::SmallPtrSet<QualType, 8> AddedTypes; 6973 6974 for (int Arg = 0; Arg < 2; ++Arg) { 6975 QualType AsymetricParamTypes[2] = { 6976 S.Context.getPointerDiffType(), 6977 S.Context.getPointerDiffType(), 6978 }; 6979 for (BuiltinCandidateTypeSet::iterator 6980 Ptr = CandidateTypes[Arg].pointer_begin(), 6981 PtrEnd = CandidateTypes[Arg].pointer_end(); 6982 Ptr != PtrEnd; ++Ptr) { 6983 QualType PointeeTy = (*Ptr)->getPointeeType(); 6984 if (!PointeeTy->isObjectType()) 6985 continue; 6986 6987 AsymetricParamTypes[Arg] = *Ptr; 6988 if (Arg == 0 || Op == OO_Plus) { 6989 // operator+(T*, ptrdiff_t) or operator-(T*, ptrdiff_t) 6990 // T* operator+(ptrdiff_t, T*); 6991 S.AddBuiltinCandidate(*Ptr, AsymetricParamTypes, Args, 2, 6992 CandidateSet); 6993 } 6994 if (Op == OO_Minus) { 6995 // ptrdiff_t operator-(T, T); 6996 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 6997 continue; 6998 6999 QualType ParamTypes[2] = { *Ptr, *Ptr }; 7000 S.AddBuiltinCandidate(S.Context.getPointerDiffType(), ParamTypes, 7001 Args, 2, CandidateSet); 7002 } 7003 } 7004 } 7005 } 7006 7007 // C++ [over.built]p12: 7008 // 7009 // For every pair of promoted arithmetic types L and R, there 7010 // exist candidate operator functions of the form 7011 // 7012 // LR operator*(L, R); 7013 // LR operator/(L, R); 7014 // LR operator+(L, R); 7015 // LR operator-(L, R); 7016 // bool operator<(L, R); 7017 // bool operator>(L, R); 7018 // bool operator<=(L, R); 7019 // bool operator>=(L, R); 7020 // bool operator==(L, R); 7021 // bool operator!=(L, R); 7022 // 7023 // where LR is the result of the usual arithmetic conversions 7024 // between types L and R. 7025 // 7026 // C++ [over.built]p24: 7027 // 7028 // For every pair of promoted arithmetic types L and R, there exist 7029 // candidate operator functions of the form 7030 // 7031 // LR operator?(bool, L, R); 7032 // 7033 // where LR is the result of the usual arithmetic conversions 7034 // between types L and R. 7035 // Our candidates ignore the first parameter. 7036 void addGenericBinaryArithmeticOverloads(bool isComparison) { 7037 if (!HasArithmeticOrEnumeralCandidateType) 7038 return; 7039 7040 for (unsigned Left = FirstPromotedArithmeticType; 7041 Left < LastPromotedArithmeticType; ++Left) { 7042 for (unsigned Right = FirstPromotedArithmeticType; 7043 Right < LastPromotedArithmeticType; ++Right) { 7044 QualType LandR[2] = { getArithmeticType(Left), 7045 getArithmeticType(Right) }; 7046 QualType Result = 7047 isComparison ? S.Context.BoolTy 7048 : getUsualArithmeticConversions(Left, Right); 7049 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 7050 } 7051 } 7052 7053 // Extension: Add the binary operators ==, !=, <, <=, >=, >, *, /, and the 7054 // conditional operator for vector types. 7055 for (BuiltinCandidateTypeSet::iterator 7056 Vec1 = CandidateTypes[0].vector_begin(), 7057 Vec1End = CandidateTypes[0].vector_end(); 7058 Vec1 != Vec1End; ++Vec1) { 7059 for (BuiltinCandidateTypeSet::iterator 7060 Vec2 = CandidateTypes[1].vector_begin(), 7061 Vec2End = CandidateTypes[1].vector_end(); 7062 Vec2 != Vec2End; ++Vec2) { 7063 QualType LandR[2] = { *Vec1, *Vec2 }; 7064 QualType Result = S.Context.BoolTy; 7065 if (!isComparison) { 7066 if ((*Vec1)->isExtVectorType() || !(*Vec2)->isExtVectorType()) 7067 Result = *Vec1; 7068 else 7069 Result = *Vec2; 7070 } 7071 7072 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 7073 } 7074 } 7075 } 7076 7077 // C++ [over.built]p17: 7078 // 7079 // For every pair of promoted integral types L and R, there 7080 // exist candidate operator functions of the form 7081 // 7082 // LR operator%(L, R); 7083 // LR operator&(L, R); 7084 // LR operator^(L, R); 7085 // LR operator|(L, R); 7086 // L operator<<(L, R); 7087 // L operator>>(L, R); 7088 // 7089 // where LR is the result of the usual arithmetic conversions 7090 // between types L and R. 7091 void addBinaryBitwiseArithmeticOverloads(OverloadedOperatorKind Op) { 7092 if (!HasArithmeticOrEnumeralCandidateType) 7093 return; 7094 7095 for (unsigned Left = FirstPromotedIntegralType; 7096 Left < LastPromotedIntegralType; ++Left) { 7097 for (unsigned Right = FirstPromotedIntegralType; 7098 Right < LastPromotedIntegralType; ++Right) { 7099 QualType LandR[2] = { getArithmeticType(Left), 7100 getArithmeticType(Right) }; 7101 QualType Result = (Op == OO_LessLess || Op == OO_GreaterGreater) 7102 ? LandR[0] 7103 : getUsualArithmeticConversions(Left, Right); 7104 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 7105 } 7106 } 7107 } 7108 7109 // C++ [over.built]p20: 7110 // 7111 // For every pair (T, VQ), where T is an enumeration or 7112 // pointer to member type and VQ is either volatile or 7113 // empty, there exist candidate operator functions of the form 7114 // 7115 // VQ T& operator=(VQ T&, T); 7116 void addAssignmentMemberPointerOrEnumeralOverloads() { 7117 /// Set of (canonical) types that we've already handled. 7118 llvm::SmallPtrSet<QualType, 8> AddedTypes; 7119 7120 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 7121 for (BuiltinCandidateTypeSet::iterator 7122 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 7123 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 7124 Enum != EnumEnd; ++Enum) { 7125 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 7126 continue; 7127 7128 AddBuiltinAssignmentOperatorCandidates(S, *Enum, Args, 2, 7129 CandidateSet); 7130 } 7131 7132 for (BuiltinCandidateTypeSet::iterator 7133 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 7134 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 7135 MemPtr != MemPtrEnd; ++MemPtr) { 7136 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 7137 continue; 7138 7139 AddBuiltinAssignmentOperatorCandidates(S, *MemPtr, Args, 2, 7140 CandidateSet); 7141 } 7142 } 7143 } 7144 7145 // C++ [over.built]p19: 7146 // 7147 // For every pair (T, VQ), where T is any type and VQ is either 7148 // volatile or empty, there exist candidate operator functions 7149 // of the form 7150 // 7151 // T*VQ& operator=(T*VQ&, T*); 7152 // 7153 // C++ [over.built]p21: 7154 // 7155 // For every pair (T, VQ), where T is a cv-qualified or 7156 // cv-unqualified object type and VQ is either volatile or 7157 // empty, there exist candidate operator functions of the form 7158 // 7159 // T*VQ& operator+=(T*VQ&, ptrdiff_t); 7160 // T*VQ& operator-=(T*VQ&, ptrdiff_t); 7161 void addAssignmentPointerOverloads(bool isEqualOp) { 7162 /// Set of (canonical) types that we've already handled. 7163 llvm::SmallPtrSet<QualType, 8> AddedTypes; 7164 7165 for (BuiltinCandidateTypeSet::iterator 7166 Ptr = CandidateTypes[0].pointer_begin(), 7167 PtrEnd = CandidateTypes[0].pointer_end(); 7168 Ptr != PtrEnd; ++Ptr) { 7169 // If this is operator=, keep track of the builtin candidates we added. 7170 if (isEqualOp) 7171 AddedTypes.insert(S.Context.getCanonicalType(*Ptr)); 7172 else if (!(*Ptr)->getPointeeType()->isObjectType()) 7173 continue; 7174 7175 // non-volatile version 7176 QualType ParamTypes[2] = { 7177 S.Context.getLValueReferenceType(*Ptr), 7178 isEqualOp ? *Ptr : S.Context.getPointerDiffType(), 7179 }; 7180 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 7181 /*IsAssigmentOperator=*/ isEqualOp); 7182 7183 bool NeedVolatile = !(*Ptr).isVolatileQualified() && 7184 VisibleTypeConversionsQuals.hasVolatile(); 7185 if (NeedVolatile) { 7186 // volatile version 7187 ParamTypes[0] = 7188 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 7189 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 7190 /*IsAssigmentOperator=*/isEqualOp); 7191 } 7192 7193 if (!(*Ptr).isRestrictQualified() && 7194 VisibleTypeConversionsQuals.hasRestrict()) { 7195 // restrict version 7196 ParamTypes[0] 7197 = S.Context.getLValueReferenceType(S.Context.getRestrictType(*Ptr)); 7198 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 7199 /*IsAssigmentOperator=*/isEqualOp); 7200 7201 if (NeedVolatile) { 7202 // volatile restrict version 7203 ParamTypes[0] 7204 = S.Context.getLValueReferenceType( 7205 S.Context.getCVRQualifiedType(*Ptr, 7206 (Qualifiers::Volatile | 7207 Qualifiers::Restrict))); 7208 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 7209 CandidateSet, 7210 /*IsAssigmentOperator=*/isEqualOp); 7211 } 7212 } 7213 } 7214 7215 if (isEqualOp) { 7216 for (BuiltinCandidateTypeSet::iterator 7217 Ptr = CandidateTypes[1].pointer_begin(), 7218 PtrEnd = CandidateTypes[1].pointer_end(); 7219 Ptr != PtrEnd; ++Ptr) { 7220 // Make sure we don't add the same candidate twice. 7221 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 7222 continue; 7223 7224 QualType ParamTypes[2] = { 7225 S.Context.getLValueReferenceType(*Ptr), 7226 *Ptr, 7227 }; 7228 7229 // non-volatile version 7230 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 7231 /*IsAssigmentOperator=*/true); 7232 7233 bool NeedVolatile = !(*Ptr).isVolatileQualified() && 7234 VisibleTypeConversionsQuals.hasVolatile(); 7235 if (NeedVolatile) { 7236 // volatile version 7237 ParamTypes[0] = 7238 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 7239 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 7240 CandidateSet, /*IsAssigmentOperator=*/true); 7241 } 7242 7243 if (!(*Ptr).isRestrictQualified() && 7244 VisibleTypeConversionsQuals.hasRestrict()) { 7245 // restrict version 7246 ParamTypes[0] 7247 = S.Context.getLValueReferenceType(S.Context.getRestrictType(*Ptr)); 7248 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 7249 CandidateSet, /*IsAssigmentOperator=*/true); 7250 7251 if (NeedVolatile) { 7252 // volatile restrict version 7253 ParamTypes[0] 7254 = S.Context.getLValueReferenceType( 7255 S.Context.getCVRQualifiedType(*Ptr, 7256 (Qualifiers::Volatile | 7257 Qualifiers::Restrict))); 7258 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 7259 CandidateSet, /*IsAssigmentOperator=*/true); 7260 7261 } 7262 } 7263 } 7264 } 7265 } 7266 7267 // C++ [over.built]p18: 7268 // 7269 // For every triple (L, VQ, R), where L is an arithmetic type, 7270 // VQ is either volatile or empty, and R is a promoted 7271 // arithmetic type, there exist candidate operator functions of 7272 // the form 7273 // 7274 // VQ L& operator=(VQ L&, R); 7275 // VQ L& operator*=(VQ L&, R); 7276 // VQ L& operator/=(VQ L&, R); 7277 // VQ L& operator+=(VQ L&, R); 7278 // VQ L& operator-=(VQ L&, R); 7279 void addAssignmentArithmeticOverloads(bool isEqualOp) { 7280 if (!HasArithmeticOrEnumeralCandidateType) 7281 return; 7282 7283 for (unsigned Left = 0; Left < NumArithmeticTypes; ++Left) { 7284 for (unsigned Right = FirstPromotedArithmeticType; 7285 Right < LastPromotedArithmeticType; ++Right) { 7286 QualType ParamTypes[2]; 7287 ParamTypes[1] = getArithmeticType(Right); 7288 7289 // Add this built-in operator as a candidate (VQ is empty). 7290 ParamTypes[0] = 7291 S.Context.getLValueReferenceType(getArithmeticType(Left)); 7292 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 7293 /*IsAssigmentOperator=*/isEqualOp); 7294 7295 // Add this built-in operator as a candidate (VQ is 'volatile'). 7296 if (VisibleTypeConversionsQuals.hasVolatile()) { 7297 ParamTypes[0] = 7298 S.Context.getVolatileType(getArithmeticType(Left)); 7299 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 7300 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 7301 CandidateSet, 7302 /*IsAssigmentOperator=*/isEqualOp); 7303 } 7304 } 7305 } 7306 7307 // Extension: Add the binary operators =, +=, -=, *=, /= for vector types. 7308 for (BuiltinCandidateTypeSet::iterator 7309 Vec1 = CandidateTypes[0].vector_begin(), 7310 Vec1End = CandidateTypes[0].vector_end(); 7311 Vec1 != Vec1End; ++Vec1) { 7312 for (BuiltinCandidateTypeSet::iterator 7313 Vec2 = CandidateTypes[1].vector_begin(), 7314 Vec2End = CandidateTypes[1].vector_end(); 7315 Vec2 != Vec2End; ++Vec2) { 7316 QualType ParamTypes[2]; 7317 ParamTypes[1] = *Vec2; 7318 // Add this built-in operator as a candidate (VQ is empty). 7319 ParamTypes[0] = S.Context.getLValueReferenceType(*Vec1); 7320 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 7321 /*IsAssigmentOperator=*/isEqualOp); 7322 7323 // Add this built-in operator as a candidate (VQ is 'volatile'). 7324 if (VisibleTypeConversionsQuals.hasVolatile()) { 7325 ParamTypes[0] = S.Context.getVolatileType(*Vec1); 7326 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 7327 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 7328 CandidateSet, 7329 /*IsAssigmentOperator=*/isEqualOp); 7330 } 7331 } 7332 } 7333 } 7334 7335 // C++ [over.built]p22: 7336 // 7337 // For every triple (L, VQ, R), where L is an integral type, VQ 7338 // is either volatile or empty, and R is a promoted integral 7339 // type, there exist candidate operator functions of the form 7340 // 7341 // VQ L& operator%=(VQ L&, R); 7342 // VQ L& operator<<=(VQ L&, R); 7343 // VQ L& operator>>=(VQ L&, R); 7344 // VQ L& operator&=(VQ L&, R); 7345 // VQ L& operator^=(VQ L&, R); 7346 // VQ L& operator|=(VQ L&, R); 7347 void addAssignmentIntegralOverloads() { 7348 if (!HasArithmeticOrEnumeralCandidateType) 7349 return; 7350 7351 for (unsigned Left = FirstIntegralType; Left < LastIntegralType; ++Left) { 7352 for (unsigned Right = FirstPromotedIntegralType; 7353 Right < LastPromotedIntegralType; ++Right) { 7354 QualType ParamTypes[2]; 7355 ParamTypes[1] = getArithmeticType(Right); 7356 7357 // Add this built-in operator as a candidate (VQ is empty). 7358 ParamTypes[0] = 7359 S.Context.getLValueReferenceType(getArithmeticType(Left)); 7360 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet); 7361 if (VisibleTypeConversionsQuals.hasVolatile()) { 7362 // Add this built-in operator as a candidate (VQ is 'volatile'). 7363 ParamTypes[0] = getArithmeticType(Left); 7364 ParamTypes[0] = S.Context.getVolatileType(ParamTypes[0]); 7365 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 7366 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 7367 CandidateSet); 7368 } 7369 } 7370 } 7371 } 7372 7373 // C++ [over.operator]p23: 7374 // 7375 // There also exist candidate operator functions of the form 7376 // 7377 // bool operator!(bool); 7378 // bool operator&&(bool, bool); 7379 // bool operator||(bool, bool); 7380 void addExclaimOverload() { 7381 QualType ParamTy = S.Context.BoolTy; 7382 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet, 7383 /*IsAssignmentOperator=*/false, 7384 /*NumContextualBoolArguments=*/1); 7385 } 7386 void addAmpAmpOrPipePipeOverload() { 7387 QualType ParamTypes[2] = { S.Context.BoolTy, S.Context.BoolTy }; 7388 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, CandidateSet, 7389 /*IsAssignmentOperator=*/false, 7390 /*NumContextualBoolArguments=*/2); 7391 } 7392 7393 // C++ [over.built]p13: 7394 // 7395 // For every cv-qualified or cv-unqualified object type T there 7396 // exist candidate operator functions of the form 7397 // 7398 // T* operator+(T*, ptrdiff_t); [ABOVE] 7399 // T& operator[](T*, ptrdiff_t); 7400 // T* operator-(T*, ptrdiff_t); [ABOVE] 7401 // T* operator+(ptrdiff_t, T*); [ABOVE] 7402 // T& operator[](ptrdiff_t, T*); 7403 void addSubscriptOverloads() { 7404 for (BuiltinCandidateTypeSet::iterator 7405 Ptr = CandidateTypes[0].pointer_begin(), 7406 PtrEnd = CandidateTypes[0].pointer_end(); 7407 Ptr != PtrEnd; ++Ptr) { 7408 QualType ParamTypes[2] = { *Ptr, S.Context.getPointerDiffType() }; 7409 QualType PointeeType = (*Ptr)->getPointeeType(); 7410 if (!PointeeType->isObjectType()) 7411 continue; 7412 7413 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 7414 7415 // T& operator[](T*, ptrdiff_t) 7416 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 7417 } 7418 7419 for (BuiltinCandidateTypeSet::iterator 7420 Ptr = CandidateTypes[1].pointer_begin(), 7421 PtrEnd = CandidateTypes[1].pointer_end(); 7422 Ptr != PtrEnd; ++Ptr) { 7423 QualType ParamTypes[2] = { S.Context.getPointerDiffType(), *Ptr }; 7424 QualType PointeeType = (*Ptr)->getPointeeType(); 7425 if (!PointeeType->isObjectType()) 7426 continue; 7427 7428 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 7429 7430 // T& operator[](ptrdiff_t, T*) 7431 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 7432 } 7433 } 7434 7435 // C++ [over.built]p11: 7436 // For every quintuple (C1, C2, T, CV1, CV2), where C2 is a class type, 7437 // C1 is the same type as C2 or is a derived class of C2, T is an object 7438 // type or a function type, and CV1 and CV2 are cv-qualifier-seqs, 7439 // there exist candidate operator functions of the form 7440 // 7441 // CV12 T& operator->*(CV1 C1*, CV2 T C2::*); 7442 // 7443 // where CV12 is the union of CV1 and CV2. 7444 void addArrowStarOverloads() { 7445 for (BuiltinCandidateTypeSet::iterator 7446 Ptr = CandidateTypes[0].pointer_begin(), 7447 PtrEnd = CandidateTypes[0].pointer_end(); 7448 Ptr != PtrEnd; ++Ptr) { 7449 QualType C1Ty = (*Ptr); 7450 QualType C1; 7451 QualifierCollector Q1; 7452 C1 = QualType(Q1.strip(C1Ty->getPointeeType()), 0); 7453 if (!isa<RecordType>(C1)) 7454 continue; 7455 // heuristic to reduce number of builtin candidates in the set. 7456 // Add volatile/restrict version only if there are conversions to a 7457 // volatile/restrict type. 7458 if (!VisibleTypeConversionsQuals.hasVolatile() && Q1.hasVolatile()) 7459 continue; 7460 if (!VisibleTypeConversionsQuals.hasRestrict() && Q1.hasRestrict()) 7461 continue; 7462 for (BuiltinCandidateTypeSet::iterator 7463 MemPtr = CandidateTypes[1].member_pointer_begin(), 7464 MemPtrEnd = CandidateTypes[1].member_pointer_end(); 7465 MemPtr != MemPtrEnd; ++MemPtr) { 7466 const MemberPointerType *mptr = cast<MemberPointerType>(*MemPtr); 7467 QualType C2 = QualType(mptr->getClass(), 0); 7468 C2 = C2.getUnqualifiedType(); 7469 if (C1 != C2 && !S.IsDerivedFrom(C1, C2)) 7470 break; 7471 QualType ParamTypes[2] = { *Ptr, *MemPtr }; 7472 // build CV12 T& 7473 QualType T = mptr->getPointeeType(); 7474 if (!VisibleTypeConversionsQuals.hasVolatile() && 7475 T.isVolatileQualified()) 7476 continue; 7477 if (!VisibleTypeConversionsQuals.hasRestrict() && 7478 T.isRestrictQualified()) 7479 continue; 7480 T = Q1.apply(S.Context, T); 7481 QualType ResultTy = S.Context.getLValueReferenceType(T); 7482 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 7483 } 7484 } 7485 } 7486 7487 // Note that we don't consider the first argument, since it has been 7488 // contextually converted to bool long ago. The candidates below are 7489 // therefore added as binary. 7490 // 7491 // C++ [over.built]p25: 7492 // For every type T, where T is a pointer, pointer-to-member, or scoped 7493 // enumeration type, there exist candidate operator functions of the form 7494 // 7495 // T operator?(bool, T, T); 7496 // 7497 void addConditionalOperatorOverloads() { 7498 /// Set of (canonical) types that we've already handled. 7499 llvm::SmallPtrSet<QualType, 8> AddedTypes; 7500 7501 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 7502 for (BuiltinCandidateTypeSet::iterator 7503 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 7504 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 7505 Ptr != PtrEnd; ++Ptr) { 7506 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 7507 continue; 7508 7509 QualType ParamTypes[2] = { *Ptr, *Ptr }; 7510 S.AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 7511 } 7512 7513 for (BuiltinCandidateTypeSet::iterator 7514 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 7515 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 7516 MemPtr != MemPtrEnd; ++MemPtr) { 7517 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 7518 continue; 7519 7520 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 7521 S.AddBuiltinCandidate(*MemPtr, ParamTypes, Args, 2, CandidateSet); 7522 } 7523 7524 if (S.getLangOpts().CPlusPlus11) { 7525 for (BuiltinCandidateTypeSet::iterator 7526 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 7527 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 7528 Enum != EnumEnd; ++Enum) { 7529 if (!(*Enum)->getAs<EnumType>()->getDecl()->isScoped()) 7530 continue; 7531 7532 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 7533 continue; 7534 7535 QualType ParamTypes[2] = { *Enum, *Enum }; 7536 S.AddBuiltinCandidate(*Enum, ParamTypes, Args, 2, CandidateSet); 7537 } 7538 } 7539 } 7540 } 7541 }; 7542 7543 } // end anonymous namespace 7544 7545 /// AddBuiltinOperatorCandidates - Add the appropriate built-in 7546 /// operator overloads to the candidate set (C++ [over.built]), based 7547 /// on the operator @p Op and the arguments given. For example, if the 7548 /// operator is a binary '+', this routine might add "int 7549 /// operator+(int, int)" to cover integer addition. 7550 void 7551 Sema::AddBuiltinOperatorCandidates(OverloadedOperatorKind Op, 7552 SourceLocation OpLoc, 7553 Expr **Args, unsigned NumArgs, 7554 OverloadCandidateSet& CandidateSet) { 7555 // Find all of the types that the arguments can convert to, but only 7556 // if the operator we're looking at has built-in operator candidates 7557 // that make use of these types. Also record whether we encounter non-record 7558 // candidate types or either arithmetic or enumeral candidate types. 7559 Qualifiers VisibleTypeConversionsQuals; 7560 VisibleTypeConversionsQuals.addConst(); 7561 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 7562 VisibleTypeConversionsQuals += CollectVRQualifiers(Context, Args[ArgIdx]); 7563 7564 bool HasNonRecordCandidateType = false; 7565 bool HasArithmeticOrEnumeralCandidateType = false; 7566 SmallVector<BuiltinCandidateTypeSet, 2> CandidateTypes; 7567 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 7568 CandidateTypes.push_back(BuiltinCandidateTypeSet(*this)); 7569 CandidateTypes[ArgIdx].AddTypesConvertedFrom(Args[ArgIdx]->getType(), 7570 OpLoc, 7571 true, 7572 (Op == OO_Exclaim || 7573 Op == OO_AmpAmp || 7574 Op == OO_PipePipe), 7575 VisibleTypeConversionsQuals); 7576 HasNonRecordCandidateType = HasNonRecordCandidateType || 7577 CandidateTypes[ArgIdx].hasNonRecordTypes(); 7578 HasArithmeticOrEnumeralCandidateType = 7579 HasArithmeticOrEnumeralCandidateType || 7580 CandidateTypes[ArgIdx].hasArithmeticOrEnumeralTypes(); 7581 } 7582 7583 // Exit early when no non-record types have been added to the candidate set 7584 // for any of the arguments to the operator. 7585 // 7586 // We can't exit early for !, ||, or &&, since there we have always have 7587 // 'bool' overloads. 7588 if (!HasNonRecordCandidateType && 7589 !(Op == OO_Exclaim || Op == OO_AmpAmp || Op == OO_PipePipe)) 7590 return; 7591 7592 // Setup an object to manage the common state for building overloads. 7593 BuiltinOperatorOverloadBuilder OpBuilder(*this, Args, NumArgs, 7594 VisibleTypeConversionsQuals, 7595 HasArithmeticOrEnumeralCandidateType, 7596 CandidateTypes, CandidateSet); 7597 7598 // Dispatch over the operation to add in only those overloads which apply. 7599 switch (Op) { 7600 case OO_None: 7601 case NUM_OVERLOADED_OPERATORS: 7602 llvm_unreachable("Expected an overloaded operator"); 7603 7604 case OO_New: 7605 case OO_Delete: 7606 case OO_Array_New: 7607 case OO_Array_Delete: 7608 case OO_Call: 7609 llvm_unreachable( 7610 "Special operators don't use AddBuiltinOperatorCandidates"); 7611 7612 case OO_Comma: 7613 case OO_Arrow: 7614 // C++ [over.match.oper]p3: 7615 // -- For the operator ',', the unary operator '&', or the 7616 // operator '->', the built-in candidates set is empty. 7617 break; 7618 7619 case OO_Plus: // '+' is either unary or binary 7620 if (NumArgs == 1) 7621 OpBuilder.addUnaryPlusPointerOverloads(); 7622 // Fall through. 7623 7624 case OO_Minus: // '-' is either unary or binary 7625 if (NumArgs == 1) { 7626 OpBuilder.addUnaryPlusOrMinusArithmeticOverloads(); 7627 } else { 7628 OpBuilder.addBinaryPlusOrMinusPointerOverloads(Op); 7629 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 7630 } 7631 break; 7632 7633 case OO_Star: // '*' is either unary or binary 7634 if (NumArgs == 1) 7635 OpBuilder.addUnaryStarPointerOverloads(); 7636 else 7637 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 7638 break; 7639 7640 case OO_Slash: 7641 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 7642 break; 7643 7644 case OO_PlusPlus: 7645 case OO_MinusMinus: 7646 OpBuilder.addPlusPlusMinusMinusArithmeticOverloads(Op); 7647 OpBuilder.addPlusPlusMinusMinusPointerOverloads(); 7648 break; 7649 7650 case OO_EqualEqual: 7651 case OO_ExclaimEqual: 7652 OpBuilder.addEqualEqualOrNotEqualMemberPointerOverloads(); 7653 // Fall through. 7654 7655 case OO_Less: 7656 case OO_Greater: 7657 case OO_LessEqual: 7658 case OO_GreaterEqual: 7659 OpBuilder.addRelationalPointerOrEnumeralOverloads(); 7660 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/true); 7661 break; 7662 7663 case OO_Percent: 7664 case OO_Caret: 7665 case OO_Pipe: 7666 case OO_LessLess: 7667 case OO_GreaterGreater: 7668 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 7669 break; 7670 7671 case OO_Amp: // '&' is either unary or binary 7672 if (NumArgs == 1) 7673 // C++ [over.match.oper]p3: 7674 // -- For the operator ',', the unary operator '&', or the 7675 // operator '->', the built-in candidates set is empty. 7676 break; 7677 7678 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 7679 break; 7680 7681 case OO_Tilde: 7682 OpBuilder.addUnaryTildePromotedIntegralOverloads(); 7683 break; 7684 7685 case OO_Equal: 7686 OpBuilder.addAssignmentMemberPointerOrEnumeralOverloads(); 7687 // Fall through. 7688 7689 case OO_PlusEqual: 7690 case OO_MinusEqual: 7691 OpBuilder.addAssignmentPointerOverloads(Op == OO_Equal); 7692 // Fall through. 7693 7694 case OO_StarEqual: 7695 case OO_SlashEqual: 7696 OpBuilder.addAssignmentArithmeticOverloads(Op == OO_Equal); 7697 break; 7698 7699 case OO_PercentEqual: 7700 case OO_LessLessEqual: 7701 case OO_GreaterGreaterEqual: 7702 case OO_AmpEqual: 7703 case OO_CaretEqual: 7704 case OO_PipeEqual: 7705 OpBuilder.addAssignmentIntegralOverloads(); 7706 break; 7707 7708 case OO_Exclaim: 7709 OpBuilder.addExclaimOverload(); 7710 break; 7711 7712 case OO_AmpAmp: 7713 case OO_PipePipe: 7714 OpBuilder.addAmpAmpOrPipePipeOverload(); 7715 break; 7716 7717 case OO_Subscript: 7718 OpBuilder.addSubscriptOverloads(); 7719 break; 7720 7721 case OO_ArrowStar: 7722 OpBuilder.addArrowStarOverloads(); 7723 break; 7724 7725 case OO_Conditional: 7726 OpBuilder.addConditionalOperatorOverloads(); 7727 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 7728 break; 7729 } 7730 } 7731 7732 /// \brief Add function candidates found via argument-dependent lookup 7733 /// to the set of overloading candidates. 7734 /// 7735 /// This routine performs argument-dependent name lookup based on the 7736 /// given function name (which may also be an operator name) and adds 7737 /// all of the overload candidates found by ADL to the overload 7738 /// candidate set (C++ [basic.lookup.argdep]). 7739 void 7740 Sema::AddArgumentDependentLookupCandidates(DeclarationName Name, 7741 bool Operator, SourceLocation Loc, 7742 ArrayRef<Expr *> Args, 7743 TemplateArgumentListInfo *ExplicitTemplateArgs, 7744 OverloadCandidateSet& CandidateSet, 7745 bool PartialOverloading) { 7746 ADLResult Fns; 7747 7748 // FIXME: This approach for uniquing ADL results (and removing 7749 // redundant candidates from the set) relies on pointer-equality, 7750 // which means we need to key off the canonical decl. However, 7751 // always going back to the canonical decl might not get us the 7752 // right set of default arguments. What default arguments are 7753 // we supposed to consider on ADL candidates, anyway? 7754 7755 // FIXME: Pass in the explicit template arguments? 7756 ArgumentDependentLookup(Name, Operator, Loc, Args, Fns); 7757 7758 // Erase all of the candidates we already knew about. 7759 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(), 7760 CandEnd = CandidateSet.end(); 7761 Cand != CandEnd; ++Cand) 7762 if (Cand->Function) { 7763 Fns.erase(Cand->Function); 7764 if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate()) 7765 Fns.erase(FunTmpl); 7766 } 7767 7768 // For each of the ADL candidates we found, add it to the overload 7769 // set. 7770 for (ADLResult::iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) { 7771 DeclAccessPair FoundDecl = DeclAccessPair::make(*I, AS_none); 7772 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) { 7773 if (ExplicitTemplateArgs) 7774 continue; 7775 7776 AddOverloadCandidate(FD, FoundDecl, Args, CandidateSet, false, 7777 PartialOverloading); 7778 } else 7779 AddTemplateOverloadCandidate(cast<FunctionTemplateDecl>(*I), 7780 FoundDecl, ExplicitTemplateArgs, 7781 Args, CandidateSet); 7782 } 7783 } 7784 7785 /// isBetterOverloadCandidate - Determines whether the first overload 7786 /// candidate is a better candidate than the second (C++ 13.3.3p1). 7787 bool 7788 isBetterOverloadCandidate(Sema &S, 7789 const OverloadCandidate &Cand1, 7790 const OverloadCandidate &Cand2, 7791 SourceLocation Loc, 7792 bool UserDefinedConversion) { 7793 // Define viable functions to be better candidates than non-viable 7794 // functions. 7795 if (!Cand2.Viable) 7796 return Cand1.Viable; 7797 else if (!Cand1.Viable) 7798 return false; 7799 7800 // C++ [over.match.best]p1: 7801 // 7802 // -- if F is a static member function, ICS1(F) is defined such 7803 // that ICS1(F) is neither better nor worse than ICS1(G) for 7804 // any function G, and, symmetrically, ICS1(G) is neither 7805 // better nor worse than ICS1(F). 7806 unsigned StartArg = 0; 7807 if (Cand1.IgnoreObjectArgument || Cand2.IgnoreObjectArgument) 7808 StartArg = 1; 7809 7810 // C++ [over.match.best]p1: 7811 // A viable function F1 is defined to be a better function than another 7812 // viable function F2 if for all arguments i, ICSi(F1) is not a worse 7813 // conversion sequence than ICSi(F2), and then... 7814 unsigned NumArgs = Cand1.NumConversions; 7815 assert(Cand2.NumConversions == NumArgs && "Overload candidate mismatch"); 7816 bool HasBetterConversion = false; 7817 for (unsigned ArgIdx = StartArg; ArgIdx < NumArgs; ++ArgIdx) { 7818 switch (CompareImplicitConversionSequences(S, 7819 Cand1.Conversions[ArgIdx], 7820 Cand2.Conversions[ArgIdx])) { 7821 case ImplicitConversionSequence::Better: 7822 // Cand1 has a better conversion sequence. 7823 HasBetterConversion = true; 7824 break; 7825 7826 case ImplicitConversionSequence::Worse: 7827 // Cand1 can't be better than Cand2. 7828 return false; 7829 7830 case ImplicitConversionSequence::Indistinguishable: 7831 // Do nothing. 7832 break; 7833 } 7834 } 7835 7836 // -- for some argument j, ICSj(F1) is a better conversion sequence than 7837 // ICSj(F2), or, if not that, 7838 if (HasBetterConversion) 7839 return true; 7840 7841 // - F1 is a non-template function and F2 is a function template 7842 // specialization, or, if not that, 7843 if ((!Cand1.Function || !Cand1.Function->getPrimaryTemplate()) && 7844 Cand2.Function && Cand2.Function->getPrimaryTemplate()) 7845 return true; 7846 7847 // -- F1 and F2 are function template specializations, and the function 7848 // template for F1 is more specialized than the template for F2 7849 // according to the partial ordering rules described in 14.5.5.2, or, 7850 // if not that, 7851 if (Cand1.Function && Cand1.Function->getPrimaryTemplate() && 7852 Cand2.Function && Cand2.Function->getPrimaryTemplate()) { 7853 if (FunctionTemplateDecl *BetterTemplate 7854 = S.getMoreSpecializedTemplate(Cand1.Function->getPrimaryTemplate(), 7855 Cand2.Function->getPrimaryTemplate(), 7856 Loc, 7857 isa<CXXConversionDecl>(Cand1.Function)? TPOC_Conversion 7858 : TPOC_Call, 7859 Cand1.ExplicitCallArguments)) 7860 return BetterTemplate == Cand1.Function->getPrimaryTemplate(); 7861 } 7862 7863 // -- the context is an initialization by user-defined conversion 7864 // (see 8.5, 13.3.1.5) and the standard conversion sequence 7865 // from the return type of F1 to the destination type (i.e., 7866 // the type of the entity being initialized) is a better 7867 // conversion sequence than the standard conversion sequence 7868 // from the return type of F2 to the destination type. 7869 if (UserDefinedConversion && Cand1.Function && Cand2.Function && 7870 isa<CXXConversionDecl>(Cand1.Function) && 7871 isa<CXXConversionDecl>(Cand2.Function)) { 7872 // First check whether we prefer one of the conversion functions over the 7873 // other. This only distinguishes the results in non-standard, extension 7874 // cases such as the conversion from a lambda closure type to a function 7875 // pointer or block. 7876 ImplicitConversionSequence::CompareKind FuncResult 7877 = compareConversionFunctions(S, Cand1.Function, Cand2.Function); 7878 if (FuncResult != ImplicitConversionSequence::Indistinguishable) 7879 return FuncResult; 7880 7881 switch (CompareStandardConversionSequences(S, 7882 Cand1.FinalConversion, 7883 Cand2.FinalConversion)) { 7884 case ImplicitConversionSequence::Better: 7885 // Cand1 has a better conversion sequence. 7886 return true; 7887 7888 case ImplicitConversionSequence::Worse: 7889 // Cand1 can't be better than Cand2. 7890 return false; 7891 7892 case ImplicitConversionSequence::Indistinguishable: 7893 // Do nothing 7894 break; 7895 } 7896 } 7897 7898 return false; 7899 } 7900 7901 /// \brief Computes the best viable function (C++ 13.3.3) 7902 /// within an overload candidate set. 7903 /// 7904 /// \param Loc The location of the function name (or operator symbol) for 7905 /// which overload resolution occurs. 7906 /// 7907 /// \param Best If overload resolution was successful or found a deleted 7908 /// function, \p Best points to the candidate function found. 7909 /// 7910 /// \returns The result of overload resolution. 7911 OverloadingResult 7912 OverloadCandidateSet::BestViableFunction(Sema &S, SourceLocation Loc, 7913 iterator &Best, 7914 bool UserDefinedConversion) { 7915 // Find the best viable function. 7916 Best = end(); 7917 for (iterator Cand = begin(); Cand != end(); ++Cand) { 7918 if (Cand->Viable) 7919 if (Best == end() || isBetterOverloadCandidate(S, *Cand, *Best, Loc, 7920 UserDefinedConversion)) 7921 Best = Cand; 7922 } 7923 7924 // If we didn't find any viable functions, abort. 7925 if (Best == end()) 7926 return OR_No_Viable_Function; 7927 7928 // Make sure that this function is better than every other viable 7929 // function. If not, we have an ambiguity. 7930 for (iterator Cand = begin(); Cand != end(); ++Cand) { 7931 if (Cand->Viable && 7932 Cand != Best && 7933 !isBetterOverloadCandidate(S, *Best, *Cand, Loc, 7934 UserDefinedConversion)) { 7935 Best = end(); 7936 return OR_Ambiguous; 7937 } 7938 } 7939 7940 // Best is the best viable function. 7941 if (Best->Function && 7942 (Best->Function->isDeleted() || 7943 S.isFunctionConsideredUnavailable(Best->Function))) 7944 return OR_Deleted; 7945 7946 return OR_Success; 7947 } 7948 7949 namespace { 7950 7951 enum OverloadCandidateKind { 7952 oc_function, 7953 oc_method, 7954 oc_constructor, 7955 oc_function_template, 7956 oc_method_template, 7957 oc_constructor_template, 7958 oc_implicit_default_constructor, 7959 oc_implicit_copy_constructor, 7960 oc_implicit_move_constructor, 7961 oc_implicit_copy_assignment, 7962 oc_implicit_move_assignment, 7963 oc_implicit_inherited_constructor 7964 }; 7965 7966 OverloadCandidateKind ClassifyOverloadCandidate(Sema &S, 7967 FunctionDecl *Fn, 7968 std::string &Description) { 7969 bool isTemplate = false; 7970 7971 if (FunctionTemplateDecl *FunTmpl = Fn->getPrimaryTemplate()) { 7972 isTemplate = true; 7973 Description = S.getTemplateArgumentBindingsText( 7974 FunTmpl->getTemplateParameters(), *Fn->getTemplateSpecializationArgs()); 7975 } 7976 7977 if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn)) { 7978 if (!Ctor->isImplicit()) 7979 return isTemplate ? oc_constructor_template : oc_constructor; 7980 7981 if (Ctor->getInheritedConstructor()) 7982 return oc_implicit_inherited_constructor; 7983 7984 if (Ctor->isDefaultConstructor()) 7985 return oc_implicit_default_constructor; 7986 7987 if (Ctor->isMoveConstructor()) 7988 return oc_implicit_move_constructor; 7989 7990 assert(Ctor->isCopyConstructor() && 7991 "unexpected sort of implicit constructor"); 7992 return oc_implicit_copy_constructor; 7993 } 7994 7995 if (CXXMethodDecl *Meth = dyn_cast<CXXMethodDecl>(Fn)) { 7996 // This actually gets spelled 'candidate function' for now, but 7997 // it doesn't hurt to split it out. 7998 if (!Meth->isImplicit()) 7999 return isTemplate ? oc_method_template : oc_method; 8000 8001 if (Meth->isMoveAssignmentOperator()) 8002 return oc_implicit_move_assignment; 8003 8004 if (Meth->isCopyAssignmentOperator()) 8005 return oc_implicit_copy_assignment; 8006 8007 assert(isa<CXXConversionDecl>(Meth) && "expected conversion"); 8008 return oc_method; 8009 } 8010 8011 return isTemplate ? oc_function_template : oc_function; 8012 } 8013 8014 void MaybeEmitInheritedConstructorNote(Sema &S, FunctionDecl *Fn) { 8015 const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn); 8016 if (!Ctor) return; 8017 8018 Ctor = Ctor->getInheritedConstructor(); 8019 if (!Ctor) return; 8020 8021 S.Diag(Ctor->getLocation(), diag::note_ovl_candidate_inherited_constructor); 8022 } 8023 8024 } // end anonymous namespace 8025 8026 // Notes the location of an overload candidate. 8027 void Sema::NoteOverloadCandidate(FunctionDecl *Fn, QualType DestType) { 8028 std::string FnDesc; 8029 OverloadCandidateKind K = ClassifyOverloadCandidate(*this, Fn, FnDesc); 8030 PartialDiagnostic PD = PDiag(diag::note_ovl_candidate) 8031 << (unsigned) K << FnDesc; 8032 HandleFunctionTypeMismatch(PD, Fn->getType(), DestType); 8033 Diag(Fn->getLocation(), PD); 8034 MaybeEmitInheritedConstructorNote(*this, Fn); 8035 } 8036 8037 //Notes the location of all overload candidates designated through 8038 // OverloadedExpr 8039 void Sema::NoteAllOverloadCandidates(Expr* OverloadedExpr, QualType DestType) { 8040 assert(OverloadedExpr->getType() == Context.OverloadTy); 8041 8042 OverloadExpr::FindResult Ovl = OverloadExpr::find(OverloadedExpr); 8043 OverloadExpr *OvlExpr = Ovl.Expression; 8044 8045 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 8046 IEnd = OvlExpr->decls_end(); 8047 I != IEnd; ++I) { 8048 if (FunctionTemplateDecl *FunTmpl = 8049 dyn_cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()) ) { 8050 NoteOverloadCandidate(FunTmpl->getTemplatedDecl(), DestType); 8051 } else if (FunctionDecl *Fun 8052 = dyn_cast<FunctionDecl>((*I)->getUnderlyingDecl()) ) { 8053 NoteOverloadCandidate(Fun, DestType); 8054 } 8055 } 8056 } 8057 8058 /// Diagnoses an ambiguous conversion. The partial diagnostic is the 8059 /// "lead" diagnostic; it will be given two arguments, the source and 8060 /// target types of the conversion. 8061 void ImplicitConversionSequence::DiagnoseAmbiguousConversion( 8062 Sema &S, 8063 SourceLocation CaretLoc, 8064 const PartialDiagnostic &PDiag) const { 8065 S.Diag(CaretLoc, PDiag) 8066 << Ambiguous.getFromType() << Ambiguous.getToType(); 8067 // FIXME: The note limiting machinery is borrowed from 8068 // OverloadCandidateSet::NoteCandidates; there's an opportunity for 8069 // refactoring here. 8070 const OverloadsShown ShowOverloads = S.Diags.getShowOverloads(); 8071 unsigned CandsShown = 0; 8072 AmbiguousConversionSequence::const_iterator I, E; 8073 for (I = Ambiguous.begin(), E = Ambiguous.end(); I != E; ++I) { 8074 if (CandsShown >= 4 && ShowOverloads == Ovl_Best) 8075 break; 8076 ++CandsShown; 8077 S.NoteOverloadCandidate(*I); 8078 } 8079 if (I != E) 8080 S.Diag(SourceLocation(), diag::note_ovl_too_many_candidates) << int(E - I); 8081 } 8082 8083 namespace { 8084 8085 void DiagnoseBadConversion(Sema &S, OverloadCandidate *Cand, unsigned I) { 8086 const ImplicitConversionSequence &Conv = Cand->Conversions[I]; 8087 assert(Conv.isBad()); 8088 assert(Cand->Function && "for now, candidate must be a function"); 8089 FunctionDecl *Fn = Cand->Function; 8090 8091 // There's a conversion slot for the object argument if this is a 8092 // non-constructor method. Note that 'I' corresponds the 8093 // conversion-slot index. 8094 bool isObjectArgument = false; 8095 if (isa<CXXMethodDecl>(Fn) && !isa<CXXConstructorDecl>(Fn)) { 8096 if (I == 0) 8097 isObjectArgument = true; 8098 else 8099 I--; 8100 } 8101 8102 std::string FnDesc; 8103 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 8104 8105 Expr *FromExpr = Conv.Bad.FromExpr; 8106 QualType FromTy = Conv.Bad.getFromType(); 8107 QualType ToTy = Conv.Bad.getToType(); 8108 8109 if (FromTy == S.Context.OverloadTy) { 8110 assert(FromExpr && "overload set argument came from implicit argument?"); 8111 Expr *E = FromExpr->IgnoreParens(); 8112 if (isa<UnaryOperator>(E)) 8113 E = cast<UnaryOperator>(E)->getSubExpr()->IgnoreParens(); 8114 DeclarationName Name = cast<OverloadExpr>(E)->getName(); 8115 8116 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_overload) 8117 << (unsigned) FnKind << FnDesc 8118 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8119 << ToTy << Name << I+1; 8120 MaybeEmitInheritedConstructorNote(S, Fn); 8121 return; 8122 } 8123 8124 // Do some hand-waving analysis to see if the non-viability is due 8125 // to a qualifier mismatch. 8126 CanQualType CFromTy = S.Context.getCanonicalType(FromTy); 8127 CanQualType CToTy = S.Context.getCanonicalType(ToTy); 8128 if (CanQual<ReferenceType> RT = CToTy->getAs<ReferenceType>()) 8129 CToTy = RT->getPointeeType(); 8130 else { 8131 // TODO: detect and diagnose the full richness of const mismatches. 8132 if (CanQual<PointerType> FromPT = CFromTy->getAs<PointerType>()) 8133 if (CanQual<PointerType> ToPT = CToTy->getAs<PointerType>()) 8134 CFromTy = FromPT->getPointeeType(), CToTy = ToPT->getPointeeType(); 8135 } 8136 8137 if (CToTy.getUnqualifiedType() == CFromTy.getUnqualifiedType() && 8138 !CToTy.isAtLeastAsQualifiedAs(CFromTy)) { 8139 Qualifiers FromQs = CFromTy.getQualifiers(); 8140 Qualifiers ToQs = CToTy.getQualifiers(); 8141 8142 if (FromQs.getAddressSpace() != ToQs.getAddressSpace()) { 8143 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_addrspace) 8144 << (unsigned) FnKind << FnDesc 8145 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8146 << FromTy 8147 << FromQs.getAddressSpace() << ToQs.getAddressSpace() 8148 << (unsigned) isObjectArgument << I+1; 8149 MaybeEmitInheritedConstructorNote(S, Fn); 8150 return; 8151 } 8152 8153 if (FromQs.getObjCLifetime() != ToQs.getObjCLifetime()) { 8154 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_ownership) 8155 << (unsigned) FnKind << FnDesc 8156 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8157 << FromTy 8158 << FromQs.getObjCLifetime() << ToQs.getObjCLifetime() 8159 << (unsigned) isObjectArgument << I+1; 8160 MaybeEmitInheritedConstructorNote(S, Fn); 8161 return; 8162 } 8163 8164 if (FromQs.getObjCGCAttr() != ToQs.getObjCGCAttr()) { 8165 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_gc) 8166 << (unsigned) FnKind << FnDesc 8167 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8168 << FromTy 8169 << FromQs.getObjCGCAttr() << ToQs.getObjCGCAttr() 8170 << (unsigned) isObjectArgument << I+1; 8171 MaybeEmitInheritedConstructorNote(S, Fn); 8172 return; 8173 } 8174 8175 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 8176 assert(CVR && "unexpected qualifiers mismatch"); 8177 8178 if (isObjectArgument) { 8179 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr_this) 8180 << (unsigned) FnKind << FnDesc 8181 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8182 << FromTy << (CVR - 1); 8183 } else { 8184 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr) 8185 << (unsigned) FnKind << FnDesc 8186 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8187 << FromTy << (CVR - 1) << I+1; 8188 } 8189 MaybeEmitInheritedConstructorNote(S, Fn); 8190 return; 8191 } 8192 8193 // Special diagnostic for failure to convert an initializer list, since 8194 // telling the user that it has type void is not useful. 8195 if (FromExpr && isa<InitListExpr>(FromExpr)) { 8196 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_list_argument) 8197 << (unsigned) FnKind << FnDesc 8198 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8199 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 8200 MaybeEmitInheritedConstructorNote(S, Fn); 8201 return; 8202 } 8203 8204 // Diagnose references or pointers to incomplete types differently, 8205 // since it's far from impossible that the incompleteness triggered 8206 // the failure. 8207 QualType TempFromTy = FromTy.getNonReferenceType(); 8208 if (const PointerType *PTy = TempFromTy->getAs<PointerType>()) 8209 TempFromTy = PTy->getPointeeType(); 8210 if (TempFromTy->isIncompleteType()) { 8211 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv_incomplete) 8212 << (unsigned) FnKind << FnDesc 8213 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8214 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 8215 MaybeEmitInheritedConstructorNote(S, Fn); 8216 return; 8217 } 8218 8219 // Diagnose base -> derived pointer conversions. 8220 unsigned BaseToDerivedConversion = 0; 8221 if (const PointerType *FromPtrTy = FromTy->getAs<PointerType>()) { 8222 if (const PointerType *ToPtrTy = ToTy->getAs<PointerType>()) { 8223 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 8224 FromPtrTy->getPointeeType()) && 8225 !FromPtrTy->getPointeeType()->isIncompleteType() && 8226 !ToPtrTy->getPointeeType()->isIncompleteType() && 8227 S.IsDerivedFrom(ToPtrTy->getPointeeType(), 8228 FromPtrTy->getPointeeType())) 8229 BaseToDerivedConversion = 1; 8230 } 8231 } else if (const ObjCObjectPointerType *FromPtrTy 8232 = FromTy->getAs<ObjCObjectPointerType>()) { 8233 if (const ObjCObjectPointerType *ToPtrTy 8234 = ToTy->getAs<ObjCObjectPointerType>()) 8235 if (const ObjCInterfaceDecl *FromIface = FromPtrTy->getInterfaceDecl()) 8236 if (const ObjCInterfaceDecl *ToIface = ToPtrTy->getInterfaceDecl()) 8237 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 8238 FromPtrTy->getPointeeType()) && 8239 FromIface->isSuperClassOf(ToIface)) 8240 BaseToDerivedConversion = 2; 8241 } else if (const ReferenceType *ToRefTy = ToTy->getAs<ReferenceType>()) { 8242 if (ToRefTy->getPointeeType().isAtLeastAsQualifiedAs(FromTy) && 8243 !FromTy->isIncompleteType() && 8244 !ToRefTy->getPointeeType()->isIncompleteType() && 8245 S.IsDerivedFrom(ToRefTy->getPointeeType(), FromTy)) { 8246 BaseToDerivedConversion = 3; 8247 } else if (ToTy->isLValueReferenceType() && !FromExpr->isLValue() && 8248 ToTy.getNonReferenceType().getCanonicalType() == 8249 FromTy.getNonReferenceType().getCanonicalType()) { 8250 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_lvalue) 8251 << (unsigned) FnKind << FnDesc 8252 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8253 << (unsigned) isObjectArgument << I + 1; 8254 MaybeEmitInheritedConstructorNote(S, Fn); 8255 return; 8256 } 8257 } 8258 8259 if (BaseToDerivedConversion) { 8260 S.Diag(Fn->getLocation(), 8261 diag::note_ovl_candidate_bad_base_to_derived_conv) 8262 << (unsigned) FnKind << FnDesc 8263 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8264 << (BaseToDerivedConversion - 1) 8265 << FromTy << ToTy << I+1; 8266 MaybeEmitInheritedConstructorNote(S, Fn); 8267 return; 8268 } 8269 8270 if (isa<ObjCObjectPointerType>(CFromTy) && 8271 isa<PointerType>(CToTy)) { 8272 Qualifiers FromQs = CFromTy.getQualifiers(); 8273 Qualifiers ToQs = CToTy.getQualifiers(); 8274 if (FromQs.getObjCLifetime() != ToQs.getObjCLifetime()) { 8275 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_arc_conv) 8276 << (unsigned) FnKind << FnDesc 8277 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8278 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 8279 MaybeEmitInheritedConstructorNote(S, Fn); 8280 return; 8281 } 8282 } 8283 8284 // Emit the generic diagnostic and, optionally, add the hints to it. 8285 PartialDiagnostic FDiag = S.PDiag(diag::note_ovl_candidate_bad_conv); 8286 FDiag << (unsigned) FnKind << FnDesc 8287 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 8288 << FromTy << ToTy << (unsigned) isObjectArgument << I + 1 8289 << (unsigned) (Cand->Fix.Kind); 8290 8291 // If we can fix the conversion, suggest the FixIts. 8292 for (std::vector<FixItHint>::iterator HI = Cand->Fix.Hints.begin(), 8293 HE = Cand->Fix.Hints.end(); HI != HE; ++HI) 8294 FDiag << *HI; 8295 S.Diag(Fn->getLocation(), FDiag); 8296 8297 MaybeEmitInheritedConstructorNote(S, Fn); 8298 } 8299 8300 void DiagnoseArityMismatch(Sema &S, OverloadCandidate *Cand, 8301 unsigned NumFormalArgs) { 8302 // TODO: treat calls to a missing default constructor as a special case 8303 8304 FunctionDecl *Fn = Cand->Function; 8305 const FunctionProtoType *FnTy = Fn->getType()->getAs<FunctionProtoType>(); 8306 8307 unsigned MinParams = Fn->getMinRequiredArguments(); 8308 8309 // With invalid overloaded operators, it's possible that we think we 8310 // have an arity mismatch when it fact it looks like we have the 8311 // right number of arguments, because only overloaded operators have 8312 // the weird behavior of overloading member and non-member functions. 8313 // Just don't report anything. 8314 if (Fn->isInvalidDecl() && 8315 Fn->getDeclName().getNameKind() == DeclarationName::CXXOperatorName) 8316 return; 8317 8318 // at least / at most / exactly 8319 unsigned mode, modeCount; 8320 if (NumFormalArgs < MinParams) { 8321 assert((Cand->FailureKind == ovl_fail_too_few_arguments) || 8322 (Cand->FailureKind == ovl_fail_bad_deduction && 8323 Cand->DeductionFailure.Result == Sema::TDK_TooFewArguments)); 8324 if (MinParams != FnTy->getNumArgs() || 8325 FnTy->isVariadic() || FnTy->isTemplateVariadic()) 8326 mode = 0; // "at least" 8327 else 8328 mode = 2; // "exactly" 8329 modeCount = MinParams; 8330 } else { 8331 assert((Cand->FailureKind == ovl_fail_too_many_arguments) || 8332 (Cand->FailureKind == ovl_fail_bad_deduction && 8333 Cand->DeductionFailure.Result == Sema::TDK_TooManyArguments)); 8334 if (MinParams != FnTy->getNumArgs()) 8335 mode = 1; // "at most" 8336 else 8337 mode = 2; // "exactly" 8338 modeCount = FnTy->getNumArgs(); 8339 } 8340 8341 std::string Description; 8342 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, Description); 8343 8344 if (modeCount == 1 && Fn->getParamDecl(0)->getDeclName()) 8345 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity_one) 8346 << (unsigned) FnKind << (Fn->getDescribedFunctionTemplate() != 0) << mode 8347 << Fn->getParamDecl(0) << NumFormalArgs; 8348 else 8349 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity) 8350 << (unsigned) FnKind << (Fn->getDescribedFunctionTemplate() != 0) << mode 8351 << modeCount << NumFormalArgs; 8352 MaybeEmitInheritedConstructorNote(S, Fn); 8353 } 8354 8355 /// Diagnose a failed template-argument deduction. 8356 void DiagnoseBadDeduction(Sema &S, OverloadCandidate *Cand, 8357 unsigned NumArgs) { 8358 FunctionDecl *Fn = Cand->Function; // pattern 8359 8360 TemplateParameter Param = Cand->DeductionFailure.getTemplateParameter(); 8361 NamedDecl *ParamD; 8362 (ParamD = Param.dyn_cast<TemplateTypeParmDecl*>()) || 8363 (ParamD = Param.dyn_cast<NonTypeTemplateParmDecl*>()) || 8364 (ParamD = Param.dyn_cast<TemplateTemplateParmDecl*>()); 8365 switch (Cand->DeductionFailure.Result) { 8366 case Sema::TDK_Success: 8367 llvm_unreachable("TDK_success while diagnosing bad deduction"); 8368 8369 case Sema::TDK_Incomplete: { 8370 assert(ParamD && "no parameter found for incomplete deduction result"); 8371 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_incomplete_deduction) 8372 << ParamD->getDeclName(); 8373 MaybeEmitInheritedConstructorNote(S, Fn); 8374 return; 8375 } 8376 8377 case Sema::TDK_Underqualified: { 8378 assert(ParamD && "no parameter found for bad qualifiers deduction result"); 8379 TemplateTypeParmDecl *TParam = cast<TemplateTypeParmDecl>(ParamD); 8380 8381 QualType Param = Cand->DeductionFailure.getFirstArg()->getAsType(); 8382 8383 // Param will have been canonicalized, but it should just be a 8384 // qualified version of ParamD, so move the qualifiers to that. 8385 QualifierCollector Qs; 8386 Qs.strip(Param); 8387 QualType NonCanonParam = Qs.apply(S.Context, TParam->getTypeForDecl()); 8388 assert(S.Context.hasSameType(Param, NonCanonParam)); 8389 8390 // Arg has also been canonicalized, but there's nothing we can do 8391 // about that. It also doesn't matter as much, because it won't 8392 // have any template parameters in it (because deduction isn't 8393 // done on dependent types). 8394 QualType Arg = Cand->DeductionFailure.getSecondArg()->getAsType(); 8395 8396 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_underqualified) 8397 << ParamD->getDeclName() << Arg << NonCanonParam; 8398 MaybeEmitInheritedConstructorNote(S, Fn); 8399 return; 8400 } 8401 8402 case Sema::TDK_Inconsistent: { 8403 assert(ParamD && "no parameter found for inconsistent deduction result"); 8404 int which = 0; 8405 if (isa<TemplateTypeParmDecl>(ParamD)) 8406 which = 0; 8407 else if (isa<NonTypeTemplateParmDecl>(ParamD)) 8408 which = 1; 8409 else { 8410 which = 2; 8411 } 8412 8413 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_inconsistent_deduction) 8414 << which << ParamD->getDeclName() 8415 << *Cand->DeductionFailure.getFirstArg() 8416 << *Cand->DeductionFailure.getSecondArg(); 8417 MaybeEmitInheritedConstructorNote(S, Fn); 8418 return; 8419 } 8420 8421 case Sema::TDK_InvalidExplicitArguments: 8422 assert(ParamD && "no parameter found for invalid explicit arguments"); 8423 if (ParamD->getDeclName()) 8424 S.Diag(Fn->getLocation(), 8425 diag::note_ovl_candidate_explicit_arg_mismatch_named) 8426 << ParamD->getDeclName(); 8427 else { 8428 int index = 0; 8429 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ParamD)) 8430 index = TTP->getIndex(); 8431 else if (NonTypeTemplateParmDecl *NTTP 8432 = dyn_cast<NonTypeTemplateParmDecl>(ParamD)) 8433 index = NTTP->getIndex(); 8434 else 8435 index = cast<TemplateTemplateParmDecl>(ParamD)->getIndex(); 8436 S.Diag(Fn->getLocation(), 8437 diag::note_ovl_candidate_explicit_arg_mismatch_unnamed) 8438 << (index + 1); 8439 } 8440 MaybeEmitInheritedConstructorNote(S, Fn); 8441 return; 8442 8443 case Sema::TDK_TooManyArguments: 8444 case Sema::TDK_TooFewArguments: 8445 DiagnoseArityMismatch(S, Cand, NumArgs); 8446 return; 8447 8448 case Sema::TDK_InstantiationDepth: 8449 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_instantiation_depth); 8450 MaybeEmitInheritedConstructorNote(S, Fn); 8451 return; 8452 8453 case Sema::TDK_SubstitutionFailure: { 8454 // Format the template argument list into the argument string. 8455 SmallString<128> TemplateArgString; 8456 if (TemplateArgumentList *Args = 8457 Cand->DeductionFailure.getTemplateArgumentList()) { 8458 TemplateArgString = " "; 8459 TemplateArgString += S.getTemplateArgumentBindingsText( 8460 Fn->getDescribedFunctionTemplate()->getTemplateParameters(), *Args); 8461 } 8462 8463 // If this candidate was disabled by enable_if, say so. 8464 PartialDiagnosticAt *PDiag = Cand->DeductionFailure.getSFINAEDiagnostic(); 8465 if (PDiag && PDiag->second.getDiagID() == 8466 diag::err_typename_nested_not_found_enable_if) { 8467 // FIXME: Use the source range of the condition, and the fully-qualified 8468 // name of the enable_if template. These are both present in PDiag. 8469 S.Diag(PDiag->first, diag::note_ovl_candidate_disabled_by_enable_if) 8470 << "'enable_if'" << TemplateArgString; 8471 return; 8472 } 8473 8474 // Format the SFINAE diagnostic into the argument string. 8475 // FIXME: Add a general mechanism to include a PartialDiagnostic *'s 8476 // formatted message in another diagnostic. 8477 SmallString<128> SFINAEArgString; 8478 SourceRange R; 8479 if (PDiag) { 8480 SFINAEArgString = ": "; 8481 R = SourceRange(PDiag->first, PDiag->first); 8482 PDiag->second.EmitToString(S.getDiagnostics(), SFINAEArgString); 8483 } 8484 8485 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_substitution_failure) 8486 << TemplateArgString << SFINAEArgString << R; 8487 MaybeEmitInheritedConstructorNote(S, Fn); 8488 return; 8489 } 8490 8491 case Sema::TDK_FailedOverloadResolution: { 8492 OverloadExpr::FindResult R = 8493 OverloadExpr::find(Cand->DeductionFailure.getExpr()); 8494 S.Diag(Fn->getLocation(), 8495 diag::note_ovl_candidate_failed_overload_resolution) 8496 << R.Expression->getName(); 8497 return; 8498 } 8499 8500 case Sema::TDK_NonDeducedMismatch: 8501 // FIXME: Provide a source location to indicate what we couldn't match. 8502 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_non_deduced_mismatch) 8503 << *Cand->DeductionFailure.getFirstArg() 8504 << *Cand->DeductionFailure.getSecondArg(); 8505 return; 8506 8507 // TODO: diagnose these individually, then kill off 8508 // note_ovl_candidate_bad_deduction, which is uselessly vague. 8509 case Sema::TDK_MiscellaneousDeductionFailure: 8510 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_deduction); 8511 MaybeEmitInheritedConstructorNote(S, Fn); 8512 return; 8513 } 8514 } 8515 8516 /// CUDA: diagnose an invalid call across targets. 8517 void DiagnoseBadTarget(Sema &S, OverloadCandidate *Cand) { 8518 FunctionDecl *Caller = cast<FunctionDecl>(S.CurContext); 8519 FunctionDecl *Callee = Cand->Function; 8520 8521 Sema::CUDAFunctionTarget CallerTarget = S.IdentifyCUDATarget(Caller), 8522 CalleeTarget = S.IdentifyCUDATarget(Callee); 8523 8524 std::string FnDesc; 8525 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Callee, FnDesc); 8526 8527 S.Diag(Callee->getLocation(), diag::note_ovl_candidate_bad_target) 8528 << (unsigned) FnKind << CalleeTarget << CallerTarget; 8529 } 8530 8531 /// Generates a 'note' diagnostic for an overload candidate. We've 8532 /// already generated a primary error at the call site. 8533 /// 8534 /// It really does need to be a single diagnostic with its caret 8535 /// pointed at the candidate declaration. Yes, this creates some 8536 /// major challenges of technical writing. Yes, this makes pointing 8537 /// out problems with specific arguments quite awkward. It's still 8538 /// better than generating twenty screens of text for every failed 8539 /// overload. 8540 /// 8541 /// It would be great to be able to express per-candidate problems 8542 /// more richly for those diagnostic clients that cared, but we'd 8543 /// still have to be just as careful with the default diagnostics. 8544 void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand, 8545 unsigned NumArgs) { 8546 FunctionDecl *Fn = Cand->Function; 8547 8548 // Note deleted candidates, but only if they're viable. 8549 if (Cand->Viable && (Fn->isDeleted() || 8550 S.isFunctionConsideredUnavailable(Fn))) { 8551 std::string FnDesc; 8552 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 8553 8554 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_deleted) 8555 << FnKind << FnDesc 8556 << (Fn->isDeleted() ? (Fn->isDeletedAsWritten() ? 1 : 2) : 0); 8557 MaybeEmitInheritedConstructorNote(S, Fn); 8558 return; 8559 } 8560 8561 // We don't really have anything else to say about viable candidates. 8562 if (Cand->Viable) { 8563 S.NoteOverloadCandidate(Fn); 8564 return; 8565 } 8566 8567 switch (Cand->FailureKind) { 8568 case ovl_fail_too_many_arguments: 8569 case ovl_fail_too_few_arguments: 8570 return DiagnoseArityMismatch(S, Cand, NumArgs); 8571 8572 case ovl_fail_bad_deduction: 8573 return DiagnoseBadDeduction(S, Cand, NumArgs); 8574 8575 case ovl_fail_trivial_conversion: 8576 case ovl_fail_bad_final_conversion: 8577 case ovl_fail_final_conversion_not_exact: 8578 return S.NoteOverloadCandidate(Fn); 8579 8580 case ovl_fail_bad_conversion: { 8581 unsigned I = (Cand->IgnoreObjectArgument ? 1 : 0); 8582 for (unsigned N = Cand->NumConversions; I != N; ++I) 8583 if (Cand->Conversions[I].isBad()) 8584 return DiagnoseBadConversion(S, Cand, I); 8585 8586 // FIXME: this currently happens when we're called from SemaInit 8587 // when user-conversion overload fails. Figure out how to handle 8588 // those conditions and diagnose them well. 8589 return S.NoteOverloadCandidate(Fn); 8590 } 8591 8592 case ovl_fail_bad_target: 8593 return DiagnoseBadTarget(S, Cand); 8594 } 8595 } 8596 8597 void NoteSurrogateCandidate(Sema &S, OverloadCandidate *Cand) { 8598 // Desugar the type of the surrogate down to a function type, 8599 // retaining as many typedefs as possible while still showing 8600 // the function type (and, therefore, its parameter types). 8601 QualType FnType = Cand->Surrogate->getConversionType(); 8602 bool isLValueReference = false; 8603 bool isRValueReference = false; 8604 bool isPointer = false; 8605 if (const LValueReferenceType *FnTypeRef = 8606 FnType->getAs<LValueReferenceType>()) { 8607 FnType = FnTypeRef->getPointeeType(); 8608 isLValueReference = true; 8609 } else if (const RValueReferenceType *FnTypeRef = 8610 FnType->getAs<RValueReferenceType>()) { 8611 FnType = FnTypeRef->getPointeeType(); 8612 isRValueReference = true; 8613 } 8614 if (const PointerType *FnTypePtr = FnType->getAs<PointerType>()) { 8615 FnType = FnTypePtr->getPointeeType(); 8616 isPointer = true; 8617 } 8618 // Desugar down to a function type. 8619 FnType = QualType(FnType->getAs<FunctionType>(), 0); 8620 // Reconstruct the pointer/reference as appropriate. 8621 if (isPointer) FnType = S.Context.getPointerType(FnType); 8622 if (isRValueReference) FnType = S.Context.getRValueReferenceType(FnType); 8623 if (isLValueReference) FnType = S.Context.getLValueReferenceType(FnType); 8624 8625 S.Diag(Cand->Surrogate->getLocation(), diag::note_ovl_surrogate_cand) 8626 << FnType; 8627 MaybeEmitInheritedConstructorNote(S, Cand->Surrogate); 8628 } 8629 8630 void NoteBuiltinOperatorCandidate(Sema &S, 8631 StringRef Opc, 8632 SourceLocation OpLoc, 8633 OverloadCandidate *Cand) { 8634 assert(Cand->NumConversions <= 2 && "builtin operator is not binary"); 8635 std::string TypeStr("operator"); 8636 TypeStr += Opc; 8637 TypeStr += "("; 8638 TypeStr += Cand->BuiltinTypes.ParamTypes[0].getAsString(); 8639 if (Cand->NumConversions == 1) { 8640 TypeStr += ")"; 8641 S.Diag(OpLoc, diag::note_ovl_builtin_unary_candidate) << TypeStr; 8642 } else { 8643 TypeStr += ", "; 8644 TypeStr += Cand->BuiltinTypes.ParamTypes[1].getAsString(); 8645 TypeStr += ")"; 8646 S.Diag(OpLoc, diag::note_ovl_builtin_binary_candidate) << TypeStr; 8647 } 8648 } 8649 8650 void NoteAmbiguousUserConversions(Sema &S, SourceLocation OpLoc, 8651 OverloadCandidate *Cand) { 8652 unsigned NoOperands = Cand->NumConversions; 8653 for (unsigned ArgIdx = 0; ArgIdx < NoOperands; ++ArgIdx) { 8654 const ImplicitConversionSequence &ICS = Cand->Conversions[ArgIdx]; 8655 if (ICS.isBad()) break; // all meaningless after first invalid 8656 if (!ICS.isAmbiguous()) continue; 8657 8658 ICS.DiagnoseAmbiguousConversion(S, OpLoc, 8659 S.PDiag(diag::note_ambiguous_type_conversion)); 8660 } 8661 } 8662 8663 SourceLocation GetLocationForCandidate(const OverloadCandidate *Cand) { 8664 if (Cand->Function) 8665 return Cand->Function->getLocation(); 8666 if (Cand->IsSurrogate) 8667 return Cand->Surrogate->getLocation(); 8668 return SourceLocation(); 8669 } 8670 8671 static unsigned 8672 RankDeductionFailure(const OverloadCandidate::DeductionFailureInfo &DFI) { 8673 switch ((Sema::TemplateDeductionResult)DFI.Result) { 8674 case Sema::TDK_Success: 8675 llvm_unreachable("TDK_success while diagnosing bad deduction"); 8676 8677 case Sema::TDK_Invalid: 8678 case Sema::TDK_Incomplete: 8679 return 1; 8680 8681 case Sema::TDK_Underqualified: 8682 case Sema::TDK_Inconsistent: 8683 return 2; 8684 8685 case Sema::TDK_SubstitutionFailure: 8686 case Sema::TDK_NonDeducedMismatch: 8687 case Sema::TDK_MiscellaneousDeductionFailure: 8688 return 3; 8689 8690 case Sema::TDK_InstantiationDepth: 8691 case Sema::TDK_FailedOverloadResolution: 8692 return 4; 8693 8694 case Sema::TDK_InvalidExplicitArguments: 8695 return 5; 8696 8697 case Sema::TDK_TooManyArguments: 8698 case Sema::TDK_TooFewArguments: 8699 return 6; 8700 } 8701 llvm_unreachable("Unhandled deduction result"); 8702 } 8703 8704 struct CompareOverloadCandidatesForDisplay { 8705 Sema &S; 8706 CompareOverloadCandidatesForDisplay(Sema &S) : S(S) {} 8707 8708 bool operator()(const OverloadCandidate *L, 8709 const OverloadCandidate *R) { 8710 // Fast-path this check. 8711 if (L == R) return false; 8712 8713 // Order first by viability. 8714 if (L->Viable) { 8715 if (!R->Viable) return true; 8716 8717 // TODO: introduce a tri-valued comparison for overload 8718 // candidates. Would be more worthwhile if we had a sort 8719 // that could exploit it. 8720 if (isBetterOverloadCandidate(S, *L, *R, SourceLocation())) return true; 8721 if (isBetterOverloadCandidate(S, *R, *L, SourceLocation())) return false; 8722 } else if (R->Viable) 8723 return false; 8724 8725 assert(L->Viable == R->Viable); 8726 8727 // Criteria by which we can sort non-viable candidates: 8728 if (!L->Viable) { 8729 // 1. Arity mismatches come after other candidates. 8730 if (L->FailureKind == ovl_fail_too_many_arguments || 8731 L->FailureKind == ovl_fail_too_few_arguments) 8732 return false; 8733 if (R->FailureKind == ovl_fail_too_many_arguments || 8734 R->FailureKind == ovl_fail_too_few_arguments) 8735 return true; 8736 8737 // 2. Bad conversions come first and are ordered by the number 8738 // of bad conversions and quality of good conversions. 8739 if (L->FailureKind == ovl_fail_bad_conversion) { 8740 if (R->FailureKind != ovl_fail_bad_conversion) 8741 return true; 8742 8743 // The conversion that can be fixed with a smaller number of changes, 8744 // comes first. 8745 unsigned numLFixes = L->Fix.NumConversionsFixed; 8746 unsigned numRFixes = R->Fix.NumConversionsFixed; 8747 numLFixes = (numLFixes == 0) ? UINT_MAX : numLFixes; 8748 numRFixes = (numRFixes == 0) ? UINT_MAX : numRFixes; 8749 if (numLFixes != numRFixes) { 8750 if (numLFixes < numRFixes) 8751 return true; 8752 else 8753 return false; 8754 } 8755 8756 // If there's any ordering between the defined conversions... 8757 // FIXME: this might not be transitive. 8758 assert(L->NumConversions == R->NumConversions); 8759 8760 int leftBetter = 0; 8761 unsigned I = (L->IgnoreObjectArgument || R->IgnoreObjectArgument); 8762 for (unsigned E = L->NumConversions; I != E; ++I) { 8763 switch (CompareImplicitConversionSequences(S, 8764 L->Conversions[I], 8765 R->Conversions[I])) { 8766 case ImplicitConversionSequence::Better: 8767 leftBetter++; 8768 break; 8769 8770 case ImplicitConversionSequence::Worse: 8771 leftBetter--; 8772 break; 8773 8774 case ImplicitConversionSequence::Indistinguishable: 8775 break; 8776 } 8777 } 8778 if (leftBetter > 0) return true; 8779 if (leftBetter < 0) return false; 8780 8781 } else if (R->FailureKind == ovl_fail_bad_conversion) 8782 return false; 8783 8784 if (L->FailureKind == ovl_fail_bad_deduction) { 8785 if (R->FailureKind != ovl_fail_bad_deduction) 8786 return true; 8787 8788 if (L->DeductionFailure.Result != R->DeductionFailure.Result) 8789 return RankDeductionFailure(L->DeductionFailure) 8790 < RankDeductionFailure(R->DeductionFailure); 8791 } else if (R->FailureKind == ovl_fail_bad_deduction) 8792 return false; 8793 8794 // TODO: others? 8795 } 8796 8797 // Sort everything else by location. 8798 SourceLocation LLoc = GetLocationForCandidate(L); 8799 SourceLocation RLoc = GetLocationForCandidate(R); 8800 8801 // Put candidates without locations (e.g. builtins) at the end. 8802 if (LLoc.isInvalid()) return false; 8803 if (RLoc.isInvalid()) return true; 8804 8805 return S.SourceMgr.isBeforeInTranslationUnit(LLoc, RLoc); 8806 } 8807 }; 8808 8809 /// CompleteNonViableCandidate - Normally, overload resolution only 8810 /// computes up to the first. Produces the FixIt set if possible. 8811 void CompleteNonViableCandidate(Sema &S, OverloadCandidate *Cand, 8812 ArrayRef<Expr *> Args) { 8813 assert(!Cand->Viable); 8814 8815 // Don't do anything on failures other than bad conversion. 8816 if (Cand->FailureKind != ovl_fail_bad_conversion) return; 8817 8818 // We only want the FixIts if all the arguments can be corrected. 8819 bool Unfixable = false; 8820 // Use a implicit copy initialization to check conversion fixes. 8821 Cand->Fix.setConversionChecker(TryCopyInitialization); 8822 8823 // Skip forward to the first bad conversion. 8824 unsigned ConvIdx = (Cand->IgnoreObjectArgument ? 1 : 0); 8825 unsigned ConvCount = Cand->NumConversions; 8826 while (true) { 8827 assert(ConvIdx != ConvCount && "no bad conversion in candidate"); 8828 ConvIdx++; 8829 if (Cand->Conversions[ConvIdx - 1].isBad()) { 8830 Unfixable = !Cand->TryToFixBadConversion(ConvIdx - 1, S); 8831 break; 8832 } 8833 } 8834 8835 if (ConvIdx == ConvCount) 8836 return; 8837 8838 assert(!Cand->Conversions[ConvIdx].isInitialized() && 8839 "remaining conversion is initialized?"); 8840 8841 // FIXME: this should probably be preserved from the overload 8842 // operation somehow. 8843 bool SuppressUserConversions = false; 8844 8845 const FunctionProtoType* Proto; 8846 unsigned ArgIdx = ConvIdx; 8847 8848 if (Cand->IsSurrogate) { 8849 QualType ConvType 8850 = Cand->Surrogate->getConversionType().getNonReferenceType(); 8851 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 8852 ConvType = ConvPtrType->getPointeeType(); 8853 Proto = ConvType->getAs<FunctionProtoType>(); 8854 ArgIdx--; 8855 } else if (Cand->Function) { 8856 Proto = Cand->Function->getType()->getAs<FunctionProtoType>(); 8857 if (isa<CXXMethodDecl>(Cand->Function) && 8858 !isa<CXXConstructorDecl>(Cand->Function)) 8859 ArgIdx--; 8860 } else { 8861 // Builtin binary operator with a bad first conversion. 8862 assert(ConvCount <= 3); 8863 for (; ConvIdx != ConvCount; ++ConvIdx) 8864 Cand->Conversions[ConvIdx] 8865 = TryCopyInitialization(S, Args[ConvIdx], 8866 Cand->BuiltinTypes.ParamTypes[ConvIdx], 8867 SuppressUserConversions, 8868 /*InOverloadResolution*/ true, 8869 /*AllowObjCWritebackConversion=*/ 8870 S.getLangOpts().ObjCAutoRefCount); 8871 return; 8872 } 8873 8874 // Fill in the rest of the conversions. 8875 unsigned NumArgsInProto = Proto->getNumArgs(); 8876 for (; ConvIdx != ConvCount; ++ConvIdx, ++ArgIdx) { 8877 if (ArgIdx < NumArgsInProto) { 8878 Cand->Conversions[ConvIdx] 8879 = TryCopyInitialization(S, Args[ArgIdx], Proto->getArgType(ArgIdx), 8880 SuppressUserConversions, 8881 /*InOverloadResolution=*/true, 8882 /*AllowObjCWritebackConversion=*/ 8883 S.getLangOpts().ObjCAutoRefCount); 8884 // Store the FixIt in the candidate if it exists. 8885 if (!Unfixable && Cand->Conversions[ConvIdx].isBad()) 8886 Unfixable = !Cand->TryToFixBadConversion(ConvIdx, S); 8887 } 8888 else 8889 Cand->Conversions[ConvIdx].setEllipsis(); 8890 } 8891 } 8892 8893 } // end anonymous namespace 8894 8895 /// PrintOverloadCandidates - When overload resolution fails, prints 8896 /// diagnostic messages containing the candidates in the candidate 8897 /// set. 8898 void OverloadCandidateSet::NoteCandidates(Sema &S, 8899 OverloadCandidateDisplayKind OCD, 8900 ArrayRef<Expr *> Args, 8901 StringRef Opc, 8902 SourceLocation OpLoc) { 8903 // Sort the candidates by viability and position. Sorting directly would 8904 // be prohibitive, so we make a set of pointers and sort those. 8905 SmallVector<OverloadCandidate*, 32> Cands; 8906 if (OCD == OCD_AllCandidates) Cands.reserve(size()); 8907 for (iterator Cand = begin(), LastCand = end(); Cand != LastCand; ++Cand) { 8908 if (Cand->Viable) 8909 Cands.push_back(Cand); 8910 else if (OCD == OCD_AllCandidates) { 8911 CompleteNonViableCandidate(S, Cand, Args); 8912 if (Cand->Function || Cand->IsSurrogate) 8913 Cands.push_back(Cand); 8914 // Otherwise, this a non-viable builtin candidate. We do not, in general, 8915 // want to list every possible builtin candidate. 8916 } 8917 } 8918 8919 std::sort(Cands.begin(), Cands.end(), 8920 CompareOverloadCandidatesForDisplay(S)); 8921 8922 bool ReportedAmbiguousConversions = false; 8923 8924 SmallVectorImpl<OverloadCandidate*>::iterator I, E; 8925 const OverloadsShown ShowOverloads = S.Diags.getShowOverloads(); 8926 unsigned CandsShown = 0; 8927 for (I = Cands.begin(), E = Cands.end(); I != E; ++I) { 8928 OverloadCandidate *Cand = *I; 8929 8930 // Set an arbitrary limit on the number of candidate functions we'll spam 8931 // the user with. FIXME: This limit should depend on details of the 8932 // candidate list. 8933 if (CandsShown >= 4 && ShowOverloads == Ovl_Best) { 8934 break; 8935 } 8936 ++CandsShown; 8937 8938 if (Cand->Function) 8939 NoteFunctionCandidate(S, Cand, Args.size()); 8940 else if (Cand->IsSurrogate) 8941 NoteSurrogateCandidate(S, Cand); 8942 else { 8943 assert(Cand->Viable && 8944 "Non-viable built-in candidates are not added to Cands."); 8945 // Generally we only see ambiguities including viable builtin 8946 // operators if overload resolution got screwed up by an 8947 // ambiguous user-defined conversion. 8948 // 8949 // FIXME: It's quite possible for different conversions to see 8950 // different ambiguities, though. 8951 if (!ReportedAmbiguousConversions) { 8952 NoteAmbiguousUserConversions(S, OpLoc, Cand); 8953 ReportedAmbiguousConversions = true; 8954 } 8955 8956 // If this is a viable builtin, print it. 8957 NoteBuiltinOperatorCandidate(S, Opc, OpLoc, Cand); 8958 } 8959 } 8960 8961 if (I != E) 8962 S.Diag(OpLoc, diag::note_ovl_too_many_candidates) << int(E - I); 8963 } 8964 8965 // [PossiblyAFunctionType] --> [Return] 8966 // NonFunctionType --> NonFunctionType 8967 // R (A) --> R(A) 8968 // R (*)(A) --> R (A) 8969 // R (&)(A) --> R (A) 8970 // R (S::*)(A) --> R (A) 8971 QualType Sema::ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType) { 8972 QualType Ret = PossiblyAFunctionType; 8973 if (const PointerType *ToTypePtr = 8974 PossiblyAFunctionType->getAs<PointerType>()) 8975 Ret = ToTypePtr->getPointeeType(); 8976 else if (const ReferenceType *ToTypeRef = 8977 PossiblyAFunctionType->getAs<ReferenceType>()) 8978 Ret = ToTypeRef->getPointeeType(); 8979 else if (const MemberPointerType *MemTypePtr = 8980 PossiblyAFunctionType->getAs<MemberPointerType>()) 8981 Ret = MemTypePtr->getPointeeType(); 8982 Ret = 8983 Context.getCanonicalType(Ret).getUnqualifiedType(); 8984 return Ret; 8985 } 8986 8987 // A helper class to help with address of function resolution 8988 // - allows us to avoid passing around all those ugly parameters 8989 class AddressOfFunctionResolver 8990 { 8991 Sema& S; 8992 Expr* SourceExpr; 8993 const QualType& TargetType; 8994 QualType TargetFunctionType; // Extracted function type from target type 8995 8996 bool Complain; 8997 //DeclAccessPair& ResultFunctionAccessPair; 8998 ASTContext& Context; 8999 9000 bool TargetTypeIsNonStaticMemberFunction; 9001 bool FoundNonTemplateFunction; 9002 9003 OverloadExpr::FindResult OvlExprInfo; 9004 OverloadExpr *OvlExpr; 9005 TemplateArgumentListInfo OvlExplicitTemplateArgs; 9006 SmallVector<std::pair<DeclAccessPair, FunctionDecl*>, 4> Matches; 9007 9008 public: 9009 AddressOfFunctionResolver(Sema &S, Expr* SourceExpr, 9010 const QualType& TargetType, bool Complain) 9011 : S(S), SourceExpr(SourceExpr), TargetType(TargetType), 9012 Complain(Complain), Context(S.getASTContext()), 9013 TargetTypeIsNonStaticMemberFunction( 9014 !!TargetType->getAs<MemberPointerType>()), 9015 FoundNonTemplateFunction(false), 9016 OvlExprInfo(OverloadExpr::find(SourceExpr)), 9017 OvlExpr(OvlExprInfo.Expression) 9018 { 9019 ExtractUnqualifiedFunctionTypeFromTargetType(); 9020 9021 if (!TargetFunctionType->isFunctionType()) { 9022 if (OvlExpr->hasExplicitTemplateArgs()) { 9023 DeclAccessPair dap; 9024 if (FunctionDecl* Fn = S.ResolveSingleFunctionTemplateSpecialization( 9025 OvlExpr, false, &dap) ) { 9026 9027 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 9028 if (!Method->isStatic()) { 9029 // If the target type is a non-function type and the function 9030 // found is a non-static member function, pretend as if that was 9031 // the target, it's the only possible type to end up with. 9032 TargetTypeIsNonStaticMemberFunction = true; 9033 9034 // And skip adding the function if its not in the proper form. 9035 // We'll diagnose this due to an empty set of functions. 9036 if (!OvlExprInfo.HasFormOfMemberPointer) 9037 return; 9038 } 9039 } 9040 9041 Matches.push_back(std::make_pair(dap,Fn)); 9042 } 9043 } 9044 return; 9045 } 9046 9047 if (OvlExpr->hasExplicitTemplateArgs()) 9048 OvlExpr->getExplicitTemplateArgs().copyInto(OvlExplicitTemplateArgs); 9049 9050 if (FindAllFunctionsThatMatchTargetTypeExactly()) { 9051 // C++ [over.over]p4: 9052 // If more than one function is selected, [...] 9053 if (Matches.size() > 1) { 9054 if (FoundNonTemplateFunction) 9055 EliminateAllTemplateMatches(); 9056 else 9057 EliminateAllExceptMostSpecializedTemplate(); 9058 } 9059 } 9060 } 9061 9062 private: 9063 bool isTargetTypeAFunction() const { 9064 return TargetFunctionType->isFunctionType(); 9065 } 9066 9067 // [ToType] [Return] 9068 9069 // R (*)(A) --> R (A), IsNonStaticMemberFunction = false 9070 // R (&)(A) --> R (A), IsNonStaticMemberFunction = false 9071 // R (S::*)(A) --> R (A), IsNonStaticMemberFunction = true 9072 void inline ExtractUnqualifiedFunctionTypeFromTargetType() { 9073 TargetFunctionType = S.ExtractUnqualifiedFunctionType(TargetType); 9074 } 9075 9076 // return true if any matching specializations were found 9077 bool AddMatchingTemplateFunction(FunctionTemplateDecl* FunctionTemplate, 9078 const DeclAccessPair& CurAccessFunPair) { 9079 if (CXXMethodDecl *Method 9080 = dyn_cast<CXXMethodDecl>(FunctionTemplate->getTemplatedDecl())) { 9081 // Skip non-static function templates when converting to pointer, and 9082 // static when converting to member pointer. 9083 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 9084 return false; 9085 } 9086 else if (TargetTypeIsNonStaticMemberFunction) 9087 return false; 9088 9089 // C++ [over.over]p2: 9090 // If the name is a function template, template argument deduction is 9091 // done (14.8.2.2), and if the argument deduction succeeds, the 9092 // resulting template argument list is used to generate a single 9093 // function template specialization, which is added to the set of 9094 // overloaded functions considered. 9095 FunctionDecl *Specialization = 0; 9096 TemplateDeductionInfo Info(OvlExpr->getNameLoc()); 9097 if (Sema::TemplateDeductionResult Result 9098 = S.DeduceTemplateArguments(FunctionTemplate, 9099 &OvlExplicitTemplateArgs, 9100 TargetFunctionType, Specialization, 9101 Info)) { 9102 // FIXME: make a note of the failed deduction for diagnostics. 9103 (void)Result; 9104 return false; 9105 } 9106 9107 // Template argument deduction ensures that we have an exact match. 9108 // This function template specicalization works. 9109 Specialization = cast<FunctionDecl>(Specialization->getCanonicalDecl()); 9110 assert(TargetFunctionType 9111 == Context.getCanonicalType(Specialization->getType())); 9112 Matches.push_back(std::make_pair(CurAccessFunPair, Specialization)); 9113 return true; 9114 } 9115 9116 bool AddMatchingNonTemplateFunction(NamedDecl* Fn, 9117 const DeclAccessPair& CurAccessFunPair) { 9118 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 9119 // Skip non-static functions when converting to pointer, and static 9120 // when converting to member pointer. 9121 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 9122 return false; 9123 } 9124 else if (TargetTypeIsNonStaticMemberFunction) 9125 return false; 9126 9127 if (FunctionDecl *FunDecl = dyn_cast<FunctionDecl>(Fn)) { 9128 if (S.getLangOpts().CUDA) 9129 if (FunctionDecl *Caller = dyn_cast<FunctionDecl>(S.CurContext)) 9130 if (S.CheckCUDATarget(Caller, FunDecl)) 9131 return false; 9132 9133 QualType ResultTy; 9134 if (Context.hasSameUnqualifiedType(TargetFunctionType, 9135 FunDecl->getType()) || 9136 S.IsNoReturnConversion(FunDecl->getType(), TargetFunctionType, 9137 ResultTy)) { 9138 Matches.push_back(std::make_pair(CurAccessFunPair, 9139 cast<FunctionDecl>(FunDecl->getCanonicalDecl()))); 9140 FoundNonTemplateFunction = true; 9141 return true; 9142 } 9143 } 9144 9145 return false; 9146 } 9147 9148 bool FindAllFunctionsThatMatchTargetTypeExactly() { 9149 bool Ret = false; 9150 9151 // If the overload expression doesn't have the form of a pointer to 9152 // member, don't try to convert it to a pointer-to-member type. 9153 if (IsInvalidFormOfPointerToMemberFunction()) 9154 return false; 9155 9156 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 9157 E = OvlExpr->decls_end(); 9158 I != E; ++I) { 9159 // Look through any using declarations to find the underlying function. 9160 NamedDecl *Fn = (*I)->getUnderlyingDecl(); 9161 9162 // C++ [over.over]p3: 9163 // Non-member functions and static member functions match 9164 // targets of type "pointer-to-function" or "reference-to-function." 9165 // Nonstatic member functions match targets of 9166 // type "pointer-to-member-function." 9167 // Note that according to DR 247, the containing class does not matter. 9168 if (FunctionTemplateDecl *FunctionTemplate 9169 = dyn_cast<FunctionTemplateDecl>(Fn)) { 9170 if (AddMatchingTemplateFunction(FunctionTemplate, I.getPair())) 9171 Ret = true; 9172 } 9173 // If we have explicit template arguments supplied, skip non-templates. 9174 else if (!OvlExpr->hasExplicitTemplateArgs() && 9175 AddMatchingNonTemplateFunction(Fn, I.getPair())) 9176 Ret = true; 9177 } 9178 assert(Ret || Matches.empty()); 9179 return Ret; 9180 } 9181 9182 void EliminateAllExceptMostSpecializedTemplate() { 9183 // [...] and any given function template specialization F1 is 9184 // eliminated if the set contains a second function template 9185 // specialization whose function template is more specialized 9186 // than the function template of F1 according to the partial 9187 // ordering rules of 14.5.5.2. 9188 9189 // The algorithm specified above is quadratic. We instead use a 9190 // two-pass algorithm (similar to the one used to identify the 9191 // best viable function in an overload set) that identifies the 9192 // best function template (if it exists). 9193 9194 UnresolvedSet<4> MatchesCopy; // TODO: avoid! 9195 for (unsigned I = 0, E = Matches.size(); I != E; ++I) 9196 MatchesCopy.addDecl(Matches[I].second, Matches[I].first.getAccess()); 9197 9198 UnresolvedSetIterator Result = 9199 S.getMostSpecialized(MatchesCopy.begin(), MatchesCopy.end(), 9200 TPOC_Other, 0, SourceExpr->getLocStart(), 9201 S.PDiag(), 9202 S.PDiag(diag::err_addr_ovl_ambiguous) 9203 << Matches[0].second->getDeclName(), 9204 S.PDiag(diag::note_ovl_candidate) 9205 << (unsigned) oc_function_template, 9206 Complain, TargetFunctionType); 9207 9208 if (Result != MatchesCopy.end()) { 9209 // Make it the first and only element 9210 Matches[0].first = Matches[Result - MatchesCopy.begin()].first; 9211 Matches[0].second = cast<FunctionDecl>(*Result); 9212 Matches.resize(1); 9213 } 9214 } 9215 9216 void EliminateAllTemplateMatches() { 9217 // [...] any function template specializations in the set are 9218 // eliminated if the set also contains a non-template function, [...] 9219 for (unsigned I = 0, N = Matches.size(); I != N; ) { 9220 if (Matches[I].second->getPrimaryTemplate() == 0) 9221 ++I; 9222 else { 9223 Matches[I] = Matches[--N]; 9224 Matches.set_size(N); 9225 } 9226 } 9227 } 9228 9229 public: 9230 void ComplainNoMatchesFound() const { 9231 assert(Matches.empty()); 9232 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_no_viable) 9233 << OvlExpr->getName() << TargetFunctionType 9234 << OvlExpr->getSourceRange(); 9235 S.NoteAllOverloadCandidates(OvlExpr, TargetFunctionType); 9236 } 9237 9238 bool IsInvalidFormOfPointerToMemberFunction() const { 9239 return TargetTypeIsNonStaticMemberFunction && 9240 !OvlExprInfo.HasFormOfMemberPointer; 9241 } 9242 9243 void ComplainIsInvalidFormOfPointerToMemberFunction() const { 9244 // TODO: Should we condition this on whether any functions might 9245 // have matched, or is it more appropriate to do that in callers? 9246 // TODO: a fixit wouldn't hurt. 9247 S.Diag(OvlExpr->getNameLoc(), diag::err_addr_ovl_no_qualifier) 9248 << TargetType << OvlExpr->getSourceRange(); 9249 } 9250 9251 void ComplainOfInvalidConversion() const { 9252 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_not_func_ptrref) 9253 << OvlExpr->getName() << TargetType; 9254 } 9255 9256 void ComplainMultipleMatchesFound() const { 9257 assert(Matches.size() > 1); 9258 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_ambiguous) 9259 << OvlExpr->getName() 9260 << OvlExpr->getSourceRange(); 9261 S.NoteAllOverloadCandidates(OvlExpr, TargetFunctionType); 9262 } 9263 9264 bool hadMultipleCandidates() const { return (OvlExpr->getNumDecls() > 1); } 9265 9266 int getNumMatches() const { return Matches.size(); } 9267 9268 FunctionDecl* getMatchingFunctionDecl() const { 9269 if (Matches.size() != 1) return 0; 9270 return Matches[0].second; 9271 } 9272 9273 const DeclAccessPair* getMatchingFunctionAccessPair() const { 9274 if (Matches.size() != 1) return 0; 9275 return &Matches[0].first; 9276 } 9277 }; 9278 9279 /// ResolveAddressOfOverloadedFunction - Try to resolve the address of 9280 /// an overloaded function (C++ [over.over]), where @p From is an 9281 /// expression with overloaded function type and @p ToType is the type 9282 /// we're trying to resolve to. For example: 9283 /// 9284 /// @code 9285 /// int f(double); 9286 /// int f(int); 9287 /// 9288 /// int (*pfd)(double) = f; // selects f(double) 9289 /// @endcode 9290 /// 9291 /// This routine returns the resulting FunctionDecl if it could be 9292 /// resolved, and NULL otherwise. When @p Complain is true, this 9293 /// routine will emit diagnostics if there is an error. 9294 FunctionDecl * 9295 Sema::ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr, 9296 QualType TargetType, 9297 bool Complain, 9298 DeclAccessPair &FoundResult, 9299 bool *pHadMultipleCandidates) { 9300 assert(AddressOfExpr->getType() == Context.OverloadTy); 9301 9302 AddressOfFunctionResolver Resolver(*this, AddressOfExpr, TargetType, 9303 Complain); 9304 int NumMatches = Resolver.getNumMatches(); 9305 FunctionDecl* Fn = 0; 9306 if (NumMatches == 0 && Complain) { 9307 if (Resolver.IsInvalidFormOfPointerToMemberFunction()) 9308 Resolver.ComplainIsInvalidFormOfPointerToMemberFunction(); 9309 else 9310 Resolver.ComplainNoMatchesFound(); 9311 } 9312 else if (NumMatches > 1 && Complain) 9313 Resolver.ComplainMultipleMatchesFound(); 9314 else if (NumMatches == 1) { 9315 Fn = Resolver.getMatchingFunctionDecl(); 9316 assert(Fn); 9317 FoundResult = *Resolver.getMatchingFunctionAccessPair(); 9318 if (Complain) 9319 CheckAddressOfMemberAccess(AddressOfExpr, FoundResult); 9320 } 9321 9322 if (pHadMultipleCandidates) 9323 *pHadMultipleCandidates = Resolver.hadMultipleCandidates(); 9324 return Fn; 9325 } 9326 9327 /// \brief Given an expression that refers to an overloaded function, try to 9328 /// resolve that overloaded function expression down to a single function. 9329 /// 9330 /// This routine can only resolve template-ids that refer to a single function 9331 /// template, where that template-id refers to a single template whose template 9332 /// arguments are either provided by the template-id or have defaults, 9333 /// as described in C++0x [temp.arg.explicit]p3. 9334 FunctionDecl * 9335 Sema::ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl, 9336 bool Complain, 9337 DeclAccessPair *FoundResult) { 9338 // C++ [over.over]p1: 9339 // [...] [Note: any redundant set of parentheses surrounding the 9340 // overloaded function name is ignored (5.1). ] 9341 // C++ [over.over]p1: 9342 // [...] The overloaded function name can be preceded by the & 9343 // operator. 9344 9345 // If we didn't actually find any template-ids, we're done. 9346 if (!ovl->hasExplicitTemplateArgs()) 9347 return 0; 9348 9349 TemplateArgumentListInfo ExplicitTemplateArgs; 9350 ovl->getExplicitTemplateArgs().copyInto(ExplicitTemplateArgs); 9351 9352 // Look through all of the overloaded functions, searching for one 9353 // whose type matches exactly. 9354 FunctionDecl *Matched = 0; 9355 for (UnresolvedSetIterator I = ovl->decls_begin(), 9356 E = ovl->decls_end(); I != E; ++I) { 9357 // C++0x [temp.arg.explicit]p3: 9358 // [...] In contexts where deduction is done and fails, or in contexts 9359 // where deduction is not done, if a template argument list is 9360 // specified and it, along with any default template arguments, 9361 // identifies a single function template specialization, then the 9362 // template-id is an lvalue for the function template specialization. 9363 FunctionTemplateDecl *FunctionTemplate 9364 = cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()); 9365 9366 // C++ [over.over]p2: 9367 // If the name is a function template, template argument deduction is 9368 // done (14.8.2.2), and if the argument deduction succeeds, the 9369 // resulting template argument list is used to generate a single 9370 // function template specialization, which is added to the set of 9371 // overloaded functions considered. 9372 FunctionDecl *Specialization = 0; 9373 TemplateDeductionInfo Info(ovl->getNameLoc()); 9374 if (TemplateDeductionResult Result 9375 = DeduceTemplateArguments(FunctionTemplate, &ExplicitTemplateArgs, 9376 Specialization, Info)) { 9377 // FIXME: make a note of the failed deduction for diagnostics. 9378 (void)Result; 9379 continue; 9380 } 9381 9382 assert(Specialization && "no specialization and no error?"); 9383 9384 // Multiple matches; we can't resolve to a single declaration. 9385 if (Matched) { 9386 if (Complain) { 9387 Diag(ovl->getExprLoc(), diag::err_addr_ovl_ambiguous) 9388 << ovl->getName(); 9389 NoteAllOverloadCandidates(ovl); 9390 } 9391 return 0; 9392 } 9393 9394 Matched = Specialization; 9395 if (FoundResult) *FoundResult = I.getPair(); 9396 } 9397 9398 return Matched; 9399 } 9400 9401 9402 9403 9404 // Resolve and fix an overloaded expression that can be resolved 9405 // because it identifies a single function template specialization. 9406 // 9407 // Last three arguments should only be supplied if Complain = true 9408 // 9409 // Return true if it was logically possible to so resolve the 9410 // expression, regardless of whether or not it succeeded. Always 9411 // returns true if 'complain' is set. 9412 bool Sema::ResolveAndFixSingleFunctionTemplateSpecialization( 9413 ExprResult &SrcExpr, bool doFunctionPointerConverion, 9414 bool complain, const SourceRange& OpRangeForComplaining, 9415 QualType DestTypeForComplaining, 9416 unsigned DiagIDForComplaining) { 9417 assert(SrcExpr.get()->getType() == Context.OverloadTy); 9418 9419 OverloadExpr::FindResult ovl = OverloadExpr::find(SrcExpr.get()); 9420 9421 DeclAccessPair found; 9422 ExprResult SingleFunctionExpression; 9423 if (FunctionDecl *fn = ResolveSingleFunctionTemplateSpecialization( 9424 ovl.Expression, /*complain*/ false, &found)) { 9425 if (DiagnoseUseOfDecl(fn, SrcExpr.get()->getLocStart())) { 9426 SrcExpr = ExprError(); 9427 return true; 9428 } 9429 9430 // It is only correct to resolve to an instance method if we're 9431 // resolving a form that's permitted to be a pointer to member. 9432 // Otherwise we'll end up making a bound member expression, which 9433 // is illegal in all the contexts we resolve like this. 9434 if (!ovl.HasFormOfMemberPointer && 9435 isa<CXXMethodDecl>(fn) && 9436 cast<CXXMethodDecl>(fn)->isInstance()) { 9437 if (!complain) return false; 9438 9439 Diag(ovl.Expression->getExprLoc(), 9440 diag::err_bound_member_function) 9441 << 0 << ovl.Expression->getSourceRange(); 9442 9443 // TODO: I believe we only end up here if there's a mix of 9444 // static and non-static candidates (otherwise the expression 9445 // would have 'bound member' type, not 'overload' type). 9446 // Ideally we would note which candidate was chosen and why 9447 // the static candidates were rejected. 9448 SrcExpr = ExprError(); 9449 return true; 9450 } 9451 9452 // Fix the expression to refer to 'fn'. 9453 SingleFunctionExpression = 9454 Owned(FixOverloadedFunctionReference(SrcExpr.take(), found, fn)); 9455 9456 // If desired, do function-to-pointer decay. 9457 if (doFunctionPointerConverion) { 9458 SingleFunctionExpression = 9459 DefaultFunctionArrayLvalueConversion(SingleFunctionExpression.take()); 9460 if (SingleFunctionExpression.isInvalid()) { 9461 SrcExpr = ExprError(); 9462 return true; 9463 } 9464 } 9465 } 9466 9467 if (!SingleFunctionExpression.isUsable()) { 9468 if (complain) { 9469 Diag(OpRangeForComplaining.getBegin(), DiagIDForComplaining) 9470 << ovl.Expression->getName() 9471 << DestTypeForComplaining 9472 << OpRangeForComplaining 9473 << ovl.Expression->getQualifierLoc().getSourceRange(); 9474 NoteAllOverloadCandidates(SrcExpr.get()); 9475 9476 SrcExpr = ExprError(); 9477 return true; 9478 } 9479 9480 return false; 9481 } 9482 9483 SrcExpr = SingleFunctionExpression; 9484 return true; 9485 } 9486 9487 /// \brief Add a single candidate to the overload set. 9488 static void AddOverloadedCallCandidate(Sema &S, 9489 DeclAccessPair FoundDecl, 9490 TemplateArgumentListInfo *ExplicitTemplateArgs, 9491 ArrayRef<Expr *> Args, 9492 OverloadCandidateSet &CandidateSet, 9493 bool PartialOverloading, 9494 bool KnownValid) { 9495 NamedDecl *Callee = FoundDecl.getDecl(); 9496 if (isa<UsingShadowDecl>(Callee)) 9497 Callee = cast<UsingShadowDecl>(Callee)->getTargetDecl(); 9498 9499 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(Callee)) { 9500 if (ExplicitTemplateArgs) { 9501 assert(!KnownValid && "Explicit template arguments?"); 9502 return; 9503 } 9504 S.AddOverloadCandidate(Func, FoundDecl, Args, CandidateSet, false, 9505 PartialOverloading); 9506 return; 9507 } 9508 9509 if (FunctionTemplateDecl *FuncTemplate 9510 = dyn_cast<FunctionTemplateDecl>(Callee)) { 9511 S.AddTemplateOverloadCandidate(FuncTemplate, FoundDecl, 9512 ExplicitTemplateArgs, Args, CandidateSet); 9513 return; 9514 } 9515 9516 assert(!KnownValid && "unhandled case in overloaded call candidate"); 9517 } 9518 9519 /// \brief Add the overload candidates named by callee and/or found by argument 9520 /// dependent lookup to the given overload set. 9521 void Sema::AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE, 9522 ArrayRef<Expr *> Args, 9523 OverloadCandidateSet &CandidateSet, 9524 bool PartialOverloading) { 9525 9526 #ifndef NDEBUG 9527 // Verify that ArgumentDependentLookup is consistent with the rules 9528 // in C++0x [basic.lookup.argdep]p3: 9529 // 9530 // Let X be the lookup set produced by unqualified lookup (3.4.1) 9531 // and let Y be the lookup set produced by argument dependent 9532 // lookup (defined as follows). If X contains 9533 // 9534 // -- a declaration of a class member, or 9535 // 9536 // -- a block-scope function declaration that is not a 9537 // using-declaration, or 9538 // 9539 // -- a declaration that is neither a function or a function 9540 // template 9541 // 9542 // then Y is empty. 9543 9544 if (ULE->requiresADL()) { 9545 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 9546 E = ULE->decls_end(); I != E; ++I) { 9547 assert(!(*I)->getDeclContext()->isRecord()); 9548 assert(isa<UsingShadowDecl>(*I) || 9549 !(*I)->getDeclContext()->isFunctionOrMethod()); 9550 assert((*I)->getUnderlyingDecl()->isFunctionOrFunctionTemplate()); 9551 } 9552 } 9553 #endif 9554 9555 // It would be nice to avoid this copy. 9556 TemplateArgumentListInfo TABuffer; 9557 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 9558 if (ULE->hasExplicitTemplateArgs()) { 9559 ULE->copyTemplateArgumentsInto(TABuffer); 9560 ExplicitTemplateArgs = &TABuffer; 9561 } 9562 9563 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 9564 E = ULE->decls_end(); I != E; ++I) 9565 AddOverloadedCallCandidate(*this, I.getPair(), ExplicitTemplateArgs, Args, 9566 CandidateSet, PartialOverloading, 9567 /*KnownValid*/ true); 9568 9569 if (ULE->requiresADL()) 9570 AddArgumentDependentLookupCandidates(ULE->getName(), /*Operator*/ false, 9571 ULE->getExprLoc(), 9572 Args, ExplicitTemplateArgs, 9573 CandidateSet, PartialOverloading); 9574 } 9575 9576 /// Attempt to recover from an ill-formed use of a non-dependent name in a 9577 /// template, where the non-dependent name was declared after the template 9578 /// was defined. This is common in code written for a compilers which do not 9579 /// correctly implement two-stage name lookup. 9580 /// 9581 /// Returns true if a viable candidate was found and a diagnostic was issued. 9582 static bool 9583 DiagnoseTwoPhaseLookup(Sema &SemaRef, SourceLocation FnLoc, 9584 const CXXScopeSpec &SS, LookupResult &R, 9585 TemplateArgumentListInfo *ExplicitTemplateArgs, 9586 ArrayRef<Expr *> Args) { 9587 if (SemaRef.ActiveTemplateInstantiations.empty() || !SS.isEmpty()) 9588 return false; 9589 9590 for (DeclContext *DC = SemaRef.CurContext; DC; DC = DC->getParent()) { 9591 if (DC->isTransparentContext()) 9592 continue; 9593 9594 SemaRef.LookupQualifiedName(R, DC); 9595 9596 if (!R.empty()) { 9597 R.suppressDiagnostics(); 9598 9599 if (isa<CXXRecordDecl>(DC)) { 9600 // Don't diagnose names we find in classes; we get much better 9601 // diagnostics for these from DiagnoseEmptyLookup. 9602 R.clear(); 9603 return false; 9604 } 9605 9606 OverloadCandidateSet Candidates(FnLoc); 9607 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 9608 AddOverloadedCallCandidate(SemaRef, I.getPair(), 9609 ExplicitTemplateArgs, Args, 9610 Candidates, false, /*KnownValid*/ false); 9611 9612 OverloadCandidateSet::iterator Best; 9613 if (Candidates.BestViableFunction(SemaRef, FnLoc, Best) != OR_Success) { 9614 // No viable functions. Don't bother the user with notes for functions 9615 // which don't work and shouldn't be found anyway. 9616 R.clear(); 9617 return false; 9618 } 9619 9620 // Find the namespaces where ADL would have looked, and suggest 9621 // declaring the function there instead. 9622 Sema::AssociatedNamespaceSet AssociatedNamespaces; 9623 Sema::AssociatedClassSet AssociatedClasses; 9624 SemaRef.FindAssociatedClassesAndNamespaces(FnLoc, Args, 9625 AssociatedNamespaces, 9626 AssociatedClasses); 9627 Sema::AssociatedNamespaceSet SuggestedNamespaces; 9628 DeclContext *Std = SemaRef.getStdNamespace(); 9629 for (Sema::AssociatedNamespaceSet::iterator 9630 it = AssociatedNamespaces.begin(), 9631 end = AssociatedNamespaces.end(); it != end; ++it) { 9632 // Never suggest declaring a function within namespace 'std'. 9633 if (Std && Std->Encloses(*it)) 9634 continue; 9635 9636 // Never suggest declaring a function within a namespace with a reserved 9637 // name, like __gnu_cxx. 9638 NamespaceDecl *NS = dyn_cast<NamespaceDecl>(*it); 9639 if (NS && 9640 NS->getQualifiedNameAsString().find("__") != std::string::npos) 9641 continue; 9642 9643 SuggestedNamespaces.insert(*it); 9644 } 9645 9646 SemaRef.Diag(R.getNameLoc(), diag::err_not_found_by_two_phase_lookup) 9647 << R.getLookupName(); 9648 if (SuggestedNamespaces.empty()) { 9649 SemaRef.Diag(Best->Function->getLocation(), 9650 diag::note_not_found_by_two_phase_lookup) 9651 << R.getLookupName() << 0; 9652 } else if (SuggestedNamespaces.size() == 1) { 9653 SemaRef.Diag(Best->Function->getLocation(), 9654 diag::note_not_found_by_two_phase_lookup) 9655 << R.getLookupName() << 1 << *SuggestedNamespaces.begin(); 9656 } else { 9657 // FIXME: It would be useful to list the associated namespaces here, 9658 // but the diagnostics infrastructure doesn't provide a way to produce 9659 // a localized representation of a list of items. 9660 SemaRef.Diag(Best->Function->getLocation(), 9661 diag::note_not_found_by_two_phase_lookup) 9662 << R.getLookupName() << 2; 9663 } 9664 9665 // Try to recover by calling this function. 9666 return true; 9667 } 9668 9669 R.clear(); 9670 } 9671 9672 return false; 9673 } 9674 9675 /// Attempt to recover from ill-formed use of a non-dependent operator in a 9676 /// template, where the non-dependent operator was declared after the template 9677 /// was defined. 9678 /// 9679 /// Returns true if a viable candidate was found and a diagnostic was issued. 9680 static bool 9681 DiagnoseTwoPhaseOperatorLookup(Sema &SemaRef, OverloadedOperatorKind Op, 9682 SourceLocation OpLoc, 9683 ArrayRef<Expr *> Args) { 9684 DeclarationName OpName = 9685 SemaRef.Context.DeclarationNames.getCXXOperatorName(Op); 9686 LookupResult R(SemaRef, OpName, OpLoc, Sema::LookupOperatorName); 9687 return DiagnoseTwoPhaseLookup(SemaRef, OpLoc, CXXScopeSpec(), R, 9688 /*ExplicitTemplateArgs=*/0, Args); 9689 } 9690 9691 namespace { 9692 // Callback to limit the allowed keywords and to only accept typo corrections 9693 // that are keywords or whose decls refer to functions (or template functions) 9694 // that accept the given number of arguments. 9695 class RecoveryCallCCC : public CorrectionCandidateCallback { 9696 public: 9697 RecoveryCallCCC(Sema &SemaRef, unsigned NumArgs, bool HasExplicitTemplateArgs) 9698 : NumArgs(NumArgs), HasExplicitTemplateArgs(HasExplicitTemplateArgs) { 9699 WantTypeSpecifiers = SemaRef.getLangOpts().CPlusPlus; 9700 WantRemainingKeywords = false; 9701 } 9702 9703 virtual bool ValidateCandidate(const TypoCorrection &candidate) { 9704 if (!candidate.getCorrectionDecl()) 9705 return candidate.isKeyword(); 9706 9707 for (TypoCorrection::const_decl_iterator DI = candidate.begin(), 9708 DIEnd = candidate.end(); DI != DIEnd; ++DI) { 9709 FunctionDecl *FD = 0; 9710 NamedDecl *ND = (*DI)->getUnderlyingDecl(); 9711 if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND)) 9712 FD = FTD->getTemplatedDecl(); 9713 if (!HasExplicitTemplateArgs && !FD) { 9714 if (!(FD = dyn_cast<FunctionDecl>(ND)) && isa<ValueDecl>(ND)) { 9715 // If the Decl is neither a function nor a template function, 9716 // determine if it is a pointer or reference to a function. If so, 9717 // check against the number of arguments expected for the pointee. 9718 QualType ValType = cast<ValueDecl>(ND)->getType(); 9719 if (ValType->isAnyPointerType() || ValType->isReferenceType()) 9720 ValType = ValType->getPointeeType(); 9721 if (const FunctionProtoType *FPT = ValType->getAs<FunctionProtoType>()) 9722 if (FPT->getNumArgs() == NumArgs) 9723 return true; 9724 } 9725 } 9726 if (FD && FD->getNumParams() >= NumArgs && 9727 FD->getMinRequiredArguments() <= NumArgs) 9728 return true; 9729 } 9730 return false; 9731 } 9732 9733 private: 9734 unsigned NumArgs; 9735 bool HasExplicitTemplateArgs; 9736 }; 9737 9738 // Callback that effectively disabled typo correction 9739 class NoTypoCorrectionCCC : public CorrectionCandidateCallback { 9740 public: 9741 NoTypoCorrectionCCC() { 9742 WantTypeSpecifiers = false; 9743 WantExpressionKeywords = false; 9744 WantCXXNamedCasts = false; 9745 WantRemainingKeywords = false; 9746 } 9747 9748 virtual bool ValidateCandidate(const TypoCorrection &candidate) { 9749 return false; 9750 } 9751 }; 9752 9753 class BuildRecoveryCallExprRAII { 9754 Sema &SemaRef; 9755 public: 9756 BuildRecoveryCallExprRAII(Sema &S) : SemaRef(S) { 9757 assert(SemaRef.IsBuildingRecoveryCallExpr == false); 9758 SemaRef.IsBuildingRecoveryCallExpr = true; 9759 } 9760 9761 ~BuildRecoveryCallExprRAII() { 9762 SemaRef.IsBuildingRecoveryCallExpr = false; 9763 } 9764 }; 9765 9766 } 9767 9768 /// Attempts to recover from a call where no functions were found. 9769 /// 9770 /// Returns true if new candidates were found. 9771 static ExprResult 9772 BuildRecoveryCallExpr(Sema &SemaRef, Scope *S, Expr *Fn, 9773 UnresolvedLookupExpr *ULE, 9774 SourceLocation LParenLoc, 9775 llvm::MutableArrayRef<Expr *> Args, 9776 SourceLocation RParenLoc, 9777 bool EmptyLookup, bool AllowTypoCorrection) { 9778 // Do not try to recover if it is already building a recovery call. 9779 // This stops infinite loops for template instantiations like 9780 // 9781 // template <typename T> auto foo(T t) -> decltype(foo(t)) {} 9782 // template <typename T> auto foo(T t) -> decltype(foo(&t)) {} 9783 // 9784 if (SemaRef.IsBuildingRecoveryCallExpr) 9785 return ExprError(); 9786 BuildRecoveryCallExprRAII RCE(SemaRef); 9787 9788 CXXScopeSpec SS; 9789 SS.Adopt(ULE->getQualifierLoc()); 9790 SourceLocation TemplateKWLoc = ULE->getTemplateKeywordLoc(); 9791 9792 TemplateArgumentListInfo TABuffer; 9793 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 9794 if (ULE->hasExplicitTemplateArgs()) { 9795 ULE->copyTemplateArgumentsInto(TABuffer); 9796 ExplicitTemplateArgs = &TABuffer; 9797 } 9798 9799 LookupResult R(SemaRef, ULE->getName(), ULE->getNameLoc(), 9800 Sema::LookupOrdinaryName); 9801 RecoveryCallCCC Validator(SemaRef, Args.size(), ExplicitTemplateArgs != 0); 9802 NoTypoCorrectionCCC RejectAll; 9803 CorrectionCandidateCallback *CCC = AllowTypoCorrection ? 9804 (CorrectionCandidateCallback*)&Validator : 9805 (CorrectionCandidateCallback*)&RejectAll; 9806 if (!DiagnoseTwoPhaseLookup(SemaRef, Fn->getExprLoc(), SS, R, 9807 ExplicitTemplateArgs, Args) && 9808 (!EmptyLookup || 9809 SemaRef.DiagnoseEmptyLookup(S, SS, R, *CCC, 9810 ExplicitTemplateArgs, Args))) 9811 return ExprError(); 9812 9813 assert(!R.empty() && "lookup results empty despite recovery"); 9814 9815 // Build an implicit member call if appropriate. Just drop the 9816 // casts and such from the call, we don't really care. 9817 ExprResult NewFn = ExprError(); 9818 if ((*R.begin())->isCXXClassMember()) 9819 NewFn = SemaRef.BuildPossibleImplicitMemberExpr(SS, TemplateKWLoc, 9820 R, ExplicitTemplateArgs); 9821 else if (ExplicitTemplateArgs || TemplateKWLoc.isValid()) 9822 NewFn = SemaRef.BuildTemplateIdExpr(SS, TemplateKWLoc, R, false, 9823 ExplicitTemplateArgs); 9824 else 9825 NewFn = SemaRef.BuildDeclarationNameExpr(SS, R, false); 9826 9827 if (NewFn.isInvalid()) 9828 return ExprError(); 9829 9830 // This shouldn't cause an infinite loop because we're giving it 9831 // an expression with viable lookup results, which should never 9832 // end up here. 9833 return SemaRef.ActOnCallExpr(/*Scope*/ 0, NewFn.take(), LParenLoc, 9834 MultiExprArg(Args.data(), Args.size()), 9835 RParenLoc); 9836 } 9837 9838 /// \brief Constructs and populates an OverloadedCandidateSet from 9839 /// the given function. 9840 /// \returns true when an the ExprResult output parameter has been set. 9841 bool Sema::buildOverloadedCallSet(Scope *S, Expr *Fn, 9842 UnresolvedLookupExpr *ULE, 9843 Expr **Args, unsigned NumArgs, 9844 SourceLocation RParenLoc, 9845 OverloadCandidateSet *CandidateSet, 9846 ExprResult *Result) { 9847 #ifndef NDEBUG 9848 if (ULE->requiresADL()) { 9849 // To do ADL, we must have found an unqualified name. 9850 assert(!ULE->getQualifier() && "qualified name with ADL"); 9851 9852 // We don't perform ADL for implicit declarations of builtins. 9853 // Verify that this was correctly set up. 9854 FunctionDecl *F; 9855 if (ULE->decls_begin() + 1 == ULE->decls_end() && 9856 (F = dyn_cast<FunctionDecl>(*ULE->decls_begin())) && 9857 F->getBuiltinID() && F->isImplicit()) 9858 llvm_unreachable("performing ADL for builtin"); 9859 9860 // We don't perform ADL in C. 9861 assert(getLangOpts().CPlusPlus && "ADL enabled in C"); 9862 } 9863 #endif 9864 9865 UnbridgedCastsSet UnbridgedCasts; 9866 if (checkArgPlaceholdersForOverload(*this, Args, NumArgs, UnbridgedCasts)) { 9867 *Result = ExprError(); 9868 return true; 9869 } 9870 9871 // Add the functions denoted by the callee to the set of candidate 9872 // functions, including those from argument-dependent lookup. 9873 AddOverloadedCallCandidates(ULE, llvm::makeArrayRef(Args, NumArgs), 9874 *CandidateSet); 9875 9876 // If we found nothing, try to recover. 9877 // BuildRecoveryCallExpr diagnoses the error itself, so we just bail 9878 // out if it fails. 9879 if (CandidateSet->empty()) { 9880 // In Microsoft mode, if we are inside a template class member function then 9881 // create a type dependent CallExpr. The goal is to postpone name lookup 9882 // to instantiation time to be able to search into type dependent base 9883 // classes. 9884 if (getLangOpts().MicrosoftMode && CurContext->isDependentContext() && 9885 (isa<FunctionDecl>(CurContext) || isa<CXXRecordDecl>(CurContext))) { 9886 CallExpr *CE = new (Context) CallExpr(Context, Fn, 9887 llvm::makeArrayRef(Args, NumArgs), 9888 Context.DependentTy, VK_RValue, 9889 RParenLoc); 9890 CE->setTypeDependent(true); 9891 *Result = Owned(CE); 9892 return true; 9893 } 9894 return false; 9895 } 9896 9897 UnbridgedCasts.restore(); 9898 return false; 9899 } 9900 9901 /// FinishOverloadedCallExpr - given an OverloadCandidateSet, builds and returns 9902 /// the completed call expression. If overload resolution fails, emits 9903 /// diagnostics and returns ExprError() 9904 static ExprResult FinishOverloadedCallExpr(Sema &SemaRef, Scope *S, Expr *Fn, 9905 UnresolvedLookupExpr *ULE, 9906 SourceLocation LParenLoc, 9907 Expr **Args, unsigned NumArgs, 9908 SourceLocation RParenLoc, 9909 Expr *ExecConfig, 9910 OverloadCandidateSet *CandidateSet, 9911 OverloadCandidateSet::iterator *Best, 9912 OverloadingResult OverloadResult, 9913 bool AllowTypoCorrection) { 9914 if (CandidateSet->empty()) 9915 return BuildRecoveryCallExpr(SemaRef, S, Fn, ULE, LParenLoc, 9916 llvm::MutableArrayRef<Expr *>(Args, NumArgs), 9917 RParenLoc, /*EmptyLookup=*/true, 9918 AllowTypoCorrection); 9919 9920 switch (OverloadResult) { 9921 case OR_Success: { 9922 FunctionDecl *FDecl = (*Best)->Function; 9923 SemaRef.CheckUnresolvedLookupAccess(ULE, (*Best)->FoundDecl); 9924 SemaRef.DiagnoseUseOfDecl(FDecl, ULE->getNameLoc()); 9925 Fn = SemaRef.FixOverloadedFunctionReference(Fn, (*Best)->FoundDecl, FDecl); 9926 return SemaRef.BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, NumArgs, 9927 RParenLoc, ExecConfig); 9928 } 9929 9930 case OR_No_Viable_Function: { 9931 // Try to recover by looking for viable functions which the user might 9932 // have meant to call. 9933 ExprResult Recovery = BuildRecoveryCallExpr(SemaRef, S, Fn, ULE, LParenLoc, 9934 llvm::MutableArrayRef<Expr *>(Args, NumArgs), 9935 RParenLoc, 9936 /*EmptyLookup=*/false, 9937 AllowTypoCorrection); 9938 if (!Recovery.isInvalid()) 9939 return Recovery; 9940 9941 SemaRef.Diag(Fn->getLocStart(), 9942 diag::err_ovl_no_viable_function_in_call) 9943 << ULE->getName() << Fn->getSourceRange(); 9944 CandidateSet->NoteCandidates(SemaRef, OCD_AllCandidates, 9945 llvm::makeArrayRef(Args, NumArgs)); 9946 break; 9947 } 9948 9949 case OR_Ambiguous: 9950 SemaRef.Diag(Fn->getLocStart(), diag::err_ovl_ambiguous_call) 9951 << ULE->getName() << Fn->getSourceRange(); 9952 CandidateSet->NoteCandidates(SemaRef, OCD_ViableCandidates, 9953 llvm::makeArrayRef(Args, NumArgs)); 9954 break; 9955 9956 case OR_Deleted: { 9957 SemaRef.Diag(Fn->getLocStart(), diag::err_ovl_deleted_call) 9958 << (*Best)->Function->isDeleted() 9959 << ULE->getName() 9960 << SemaRef.getDeletedOrUnavailableSuffix((*Best)->Function) 9961 << Fn->getSourceRange(); 9962 CandidateSet->NoteCandidates(SemaRef, OCD_AllCandidates, 9963 llvm::makeArrayRef(Args, NumArgs)); 9964 9965 // We emitted an error for the unvailable/deleted function call but keep 9966 // the call in the AST. 9967 FunctionDecl *FDecl = (*Best)->Function; 9968 Fn = SemaRef.FixOverloadedFunctionReference(Fn, (*Best)->FoundDecl, FDecl); 9969 return SemaRef.BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, NumArgs, 9970 RParenLoc, ExecConfig); 9971 } 9972 } 9973 9974 // Overload resolution failed. 9975 return ExprError(); 9976 } 9977 9978 /// BuildOverloadedCallExpr - Given the call expression that calls Fn 9979 /// (which eventually refers to the declaration Func) and the call 9980 /// arguments Args/NumArgs, attempt to resolve the function call down 9981 /// to a specific function. If overload resolution succeeds, returns 9982 /// the call expression produced by overload resolution. 9983 /// Otherwise, emits diagnostics and returns ExprError. 9984 ExprResult Sema::BuildOverloadedCallExpr(Scope *S, Expr *Fn, 9985 UnresolvedLookupExpr *ULE, 9986 SourceLocation LParenLoc, 9987 Expr **Args, unsigned NumArgs, 9988 SourceLocation RParenLoc, 9989 Expr *ExecConfig, 9990 bool AllowTypoCorrection) { 9991 OverloadCandidateSet CandidateSet(Fn->getExprLoc()); 9992 ExprResult result; 9993 9994 if (buildOverloadedCallSet(S, Fn, ULE, Args, NumArgs, LParenLoc, 9995 &CandidateSet, &result)) 9996 return result; 9997 9998 OverloadCandidateSet::iterator Best; 9999 OverloadingResult OverloadResult = 10000 CandidateSet.BestViableFunction(*this, Fn->getLocStart(), Best); 10001 10002 return FinishOverloadedCallExpr(*this, S, Fn, ULE, LParenLoc, Args, NumArgs, 10003 RParenLoc, ExecConfig, &CandidateSet, 10004 &Best, OverloadResult, 10005 AllowTypoCorrection); 10006 } 10007 10008 static bool IsOverloaded(const UnresolvedSetImpl &Functions) { 10009 return Functions.size() > 1 || 10010 (Functions.size() == 1 && isa<FunctionTemplateDecl>(*Functions.begin())); 10011 } 10012 10013 /// \brief Create a unary operation that may resolve to an overloaded 10014 /// operator. 10015 /// 10016 /// \param OpLoc The location of the operator itself (e.g., '*'). 10017 /// 10018 /// \param OpcIn The UnaryOperator::Opcode that describes this 10019 /// operator. 10020 /// 10021 /// \param Fns The set of non-member functions that will be 10022 /// considered by overload resolution. The caller needs to build this 10023 /// set based on the context using, e.g., 10024 /// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 10025 /// set should not contain any member functions; those will be added 10026 /// by CreateOverloadedUnaryOp(). 10027 /// 10028 /// \param Input The input argument. 10029 ExprResult 10030 Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, unsigned OpcIn, 10031 const UnresolvedSetImpl &Fns, 10032 Expr *Input) { 10033 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 10034 10035 OverloadedOperatorKind Op = UnaryOperator::getOverloadedOperator(Opc); 10036 assert(Op != OO_None && "Invalid opcode for overloaded unary operator"); 10037 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 10038 // TODO: provide better source location info. 10039 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 10040 10041 if (checkPlaceholderForOverload(*this, Input)) 10042 return ExprError(); 10043 10044 Expr *Args[2] = { Input, 0 }; 10045 unsigned NumArgs = 1; 10046 10047 // For post-increment and post-decrement, add the implicit '0' as 10048 // the second argument, so that we know this is a post-increment or 10049 // post-decrement. 10050 if (Opc == UO_PostInc || Opc == UO_PostDec) { 10051 llvm::APSInt Zero(Context.getTypeSize(Context.IntTy), false); 10052 Args[1] = IntegerLiteral::Create(Context, Zero, Context.IntTy, 10053 SourceLocation()); 10054 NumArgs = 2; 10055 } 10056 10057 if (Input->isTypeDependent()) { 10058 if (Fns.empty()) 10059 return Owned(new (Context) UnaryOperator(Input, 10060 Opc, 10061 Context.DependentTy, 10062 VK_RValue, OK_Ordinary, 10063 OpLoc)); 10064 10065 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 10066 UnresolvedLookupExpr *Fn 10067 = UnresolvedLookupExpr::Create(Context, NamingClass, 10068 NestedNameSpecifierLoc(), OpNameInfo, 10069 /*ADL*/ true, IsOverloaded(Fns), 10070 Fns.begin(), Fns.end()); 10071 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 10072 llvm::makeArrayRef(Args, NumArgs), 10073 Context.DependentTy, 10074 VK_RValue, 10075 OpLoc, false)); 10076 } 10077 10078 // Build an empty overload set. 10079 OverloadCandidateSet CandidateSet(OpLoc); 10080 10081 // Add the candidates from the given function set. 10082 AddFunctionCandidates(Fns, llvm::makeArrayRef(Args, NumArgs), CandidateSet, 10083 false); 10084 10085 // Add operator candidates that are member functions. 10086 AddMemberOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 10087 10088 // Add candidates from ADL. 10089 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 10090 OpLoc, llvm::makeArrayRef(Args, NumArgs), 10091 /*ExplicitTemplateArgs*/ 0, 10092 CandidateSet); 10093 10094 // Add builtin operator candidates. 10095 AddBuiltinOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 10096 10097 bool HadMultipleCandidates = (CandidateSet.size() > 1); 10098 10099 // Perform overload resolution. 10100 OverloadCandidateSet::iterator Best; 10101 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 10102 case OR_Success: { 10103 // We found a built-in operator or an overloaded operator. 10104 FunctionDecl *FnDecl = Best->Function; 10105 10106 if (FnDecl) { 10107 // We matched an overloaded operator. Build a call to that 10108 // operator. 10109 10110 // Convert the arguments. 10111 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 10112 CheckMemberOperatorAccess(OpLoc, Args[0], 0, Best->FoundDecl); 10113 10114 ExprResult InputRes = 10115 PerformObjectArgumentInitialization(Input, /*Qualifier=*/0, 10116 Best->FoundDecl, Method); 10117 if (InputRes.isInvalid()) 10118 return ExprError(); 10119 Input = InputRes.take(); 10120 } else { 10121 // Convert the arguments. 10122 ExprResult InputInit 10123 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 10124 Context, 10125 FnDecl->getParamDecl(0)), 10126 SourceLocation(), 10127 Input); 10128 if (InputInit.isInvalid()) 10129 return ExprError(); 10130 Input = InputInit.take(); 10131 } 10132 10133 // Determine the result type. 10134 QualType ResultTy = FnDecl->getResultType(); 10135 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 10136 ResultTy = ResultTy.getNonLValueExprType(Context); 10137 10138 // Build the actual expression node. 10139 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, Best->FoundDecl, 10140 HadMultipleCandidates, OpLoc); 10141 if (FnExpr.isInvalid()) 10142 return ExprError(); 10143 10144 Args[0] = Input; 10145 CallExpr *TheCall = 10146 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 10147 llvm::makeArrayRef(Args, NumArgs), 10148 ResultTy, VK, OpLoc, false); 10149 10150 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 10151 FnDecl)) 10152 return ExprError(); 10153 10154 return MaybeBindToTemporary(TheCall); 10155 } else { 10156 // We matched a built-in operator. Convert the arguments, then 10157 // break out so that we will build the appropriate built-in 10158 // operator node. 10159 ExprResult InputRes = 10160 PerformImplicitConversion(Input, Best->BuiltinTypes.ParamTypes[0], 10161 Best->Conversions[0], AA_Passing); 10162 if (InputRes.isInvalid()) 10163 return ExprError(); 10164 Input = InputRes.take(); 10165 break; 10166 } 10167 } 10168 10169 case OR_No_Viable_Function: 10170 // This is an erroneous use of an operator which can be overloaded by 10171 // a non-member function. Check for non-member operators which were 10172 // defined too late to be candidates. 10173 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, 10174 llvm::makeArrayRef(Args, NumArgs))) 10175 // FIXME: Recover by calling the found function. 10176 return ExprError(); 10177 10178 // No viable function; fall through to handling this as a 10179 // built-in operator, which will produce an error message for us. 10180 break; 10181 10182 case OR_Ambiguous: 10183 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 10184 << UnaryOperator::getOpcodeStr(Opc) 10185 << Input->getType() 10186 << Input->getSourceRange(); 10187 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, 10188 llvm::makeArrayRef(Args, NumArgs), 10189 UnaryOperator::getOpcodeStr(Opc), OpLoc); 10190 return ExprError(); 10191 10192 case OR_Deleted: 10193 Diag(OpLoc, diag::err_ovl_deleted_oper) 10194 << Best->Function->isDeleted() 10195 << UnaryOperator::getOpcodeStr(Opc) 10196 << getDeletedOrUnavailableSuffix(Best->Function) 10197 << Input->getSourceRange(); 10198 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, 10199 llvm::makeArrayRef(Args, NumArgs), 10200 UnaryOperator::getOpcodeStr(Opc), OpLoc); 10201 return ExprError(); 10202 } 10203 10204 // Either we found no viable overloaded operator or we matched a 10205 // built-in operator. In either case, fall through to trying to 10206 // build a built-in operation. 10207 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 10208 } 10209 10210 /// \brief Create a binary operation that may resolve to an overloaded 10211 /// operator. 10212 /// 10213 /// \param OpLoc The location of the operator itself (e.g., '+'). 10214 /// 10215 /// \param OpcIn The BinaryOperator::Opcode that describes this 10216 /// operator. 10217 /// 10218 /// \param Fns The set of non-member functions that will be 10219 /// considered by overload resolution. The caller needs to build this 10220 /// set based on the context using, e.g., 10221 /// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 10222 /// set should not contain any member functions; those will be added 10223 /// by CreateOverloadedBinOp(). 10224 /// 10225 /// \param LHS Left-hand argument. 10226 /// \param RHS Right-hand argument. 10227 ExprResult 10228 Sema::CreateOverloadedBinOp(SourceLocation OpLoc, 10229 unsigned OpcIn, 10230 const UnresolvedSetImpl &Fns, 10231 Expr *LHS, Expr *RHS) { 10232 Expr *Args[2] = { LHS, RHS }; 10233 LHS=RHS=0; //Please use only Args instead of LHS/RHS couple 10234 10235 BinaryOperator::Opcode Opc = static_cast<BinaryOperator::Opcode>(OpcIn); 10236 OverloadedOperatorKind Op = BinaryOperator::getOverloadedOperator(Opc); 10237 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 10238 10239 // If either side is type-dependent, create an appropriate dependent 10240 // expression. 10241 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 10242 if (Fns.empty()) { 10243 // If there are no functions to store, just build a dependent 10244 // BinaryOperator or CompoundAssignment. 10245 if (Opc <= BO_Assign || Opc > BO_OrAssign) 10246 return Owned(new (Context) BinaryOperator(Args[0], Args[1], Opc, 10247 Context.DependentTy, 10248 VK_RValue, OK_Ordinary, 10249 OpLoc, 10250 FPFeatures.fp_contract)); 10251 10252 return Owned(new (Context) CompoundAssignOperator(Args[0], Args[1], Opc, 10253 Context.DependentTy, 10254 VK_LValue, 10255 OK_Ordinary, 10256 Context.DependentTy, 10257 Context.DependentTy, 10258 OpLoc, 10259 FPFeatures.fp_contract)); 10260 } 10261 10262 // FIXME: save results of ADL from here? 10263 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 10264 // TODO: provide better source location info in DNLoc component. 10265 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 10266 UnresolvedLookupExpr *Fn 10267 = UnresolvedLookupExpr::Create(Context, NamingClass, 10268 NestedNameSpecifierLoc(), OpNameInfo, 10269 /*ADL*/ true, IsOverloaded(Fns), 10270 Fns.begin(), Fns.end()); 10271 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, Args, 10272 Context.DependentTy, VK_RValue, 10273 OpLoc, FPFeatures.fp_contract)); 10274 } 10275 10276 // Always do placeholder-like conversions on the RHS. 10277 if (checkPlaceholderForOverload(*this, Args[1])) 10278 return ExprError(); 10279 10280 // Do placeholder-like conversion on the LHS; note that we should 10281 // not get here with a PseudoObject LHS. 10282 assert(Args[0]->getObjectKind() != OK_ObjCProperty); 10283 if (checkPlaceholderForOverload(*this, Args[0])) 10284 return ExprError(); 10285 10286 // If this is the assignment operator, we only perform overload resolution 10287 // if the left-hand side is a class or enumeration type. This is actually 10288 // a hack. The standard requires that we do overload resolution between the 10289 // various built-in candidates, but as DR507 points out, this can lead to 10290 // problems. So we do it this way, which pretty much follows what GCC does. 10291 // Note that we go the traditional code path for compound assignment forms. 10292 if (Opc == BO_Assign && !Args[0]->getType()->isOverloadableType()) 10293 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 10294 10295 // If this is the .* operator, which is not overloadable, just 10296 // create a built-in binary operator. 10297 if (Opc == BO_PtrMemD) 10298 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 10299 10300 // Build an empty overload set. 10301 OverloadCandidateSet CandidateSet(OpLoc); 10302 10303 // Add the candidates from the given function set. 10304 AddFunctionCandidates(Fns, Args, CandidateSet, false); 10305 10306 // Add operator candidates that are member functions. 10307 AddMemberOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 10308 10309 // Add candidates from ADL. 10310 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 10311 OpLoc, Args, 10312 /*ExplicitTemplateArgs*/ 0, 10313 CandidateSet); 10314 10315 // Add builtin operator candidates. 10316 AddBuiltinOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 10317 10318 bool HadMultipleCandidates = (CandidateSet.size() > 1); 10319 10320 // Perform overload resolution. 10321 OverloadCandidateSet::iterator Best; 10322 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 10323 case OR_Success: { 10324 // We found a built-in operator or an overloaded operator. 10325 FunctionDecl *FnDecl = Best->Function; 10326 10327 if (FnDecl) { 10328 // We matched an overloaded operator. Build a call to that 10329 // operator. 10330 10331 // Convert the arguments. 10332 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 10333 // Best->Access is only meaningful for class members. 10334 CheckMemberOperatorAccess(OpLoc, Args[0], Args[1], Best->FoundDecl); 10335 10336 ExprResult Arg1 = 10337 PerformCopyInitialization( 10338 InitializedEntity::InitializeParameter(Context, 10339 FnDecl->getParamDecl(0)), 10340 SourceLocation(), Owned(Args[1])); 10341 if (Arg1.isInvalid()) 10342 return ExprError(); 10343 10344 ExprResult Arg0 = 10345 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 10346 Best->FoundDecl, Method); 10347 if (Arg0.isInvalid()) 10348 return ExprError(); 10349 Args[0] = Arg0.takeAs<Expr>(); 10350 Args[1] = RHS = Arg1.takeAs<Expr>(); 10351 } else { 10352 // Convert the arguments. 10353 ExprResult Arg0 = PerformCopyInitialization( 10354 InitializedEntity::InitializeParameter(Context, 10355 FnDecl->getParamDecl(0)), 10356 SourceLocation(), Owned(Args[0])); 10357 if (Arg0.isInvalid()) 10358 return ExprError(); 10359 10360 ExprResult Arg1 = 10361 PerformCopyInitialization( 10362 InitializedEntity::InitializeParameter(Context, 10363 FnDecl->getParamDecl(1)), 10364 SourceLocation(), Owned(Args[1])); 10365 if (Arg1.isInvalid()) 10366 return ExprError(); 10367 Args[0] = LHS = Arg0.takeAs<Expr>(); 10368 Args[1] = RHS = Arg1.takeAs<Expr>(); 10369 } 10370 10371 // Determine the result type. 10372 QualType ResultTy = FnDecl->getResultType(); 10373 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 10374 ResultTy = ResultTy.getNonLValueExprType(Context); 10375 10376 // Build the actual expression node. 10377 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, 10378 Best->FoundDecl, 10379 HadMultipleCandidates, OpLoc); 10380 if (FnExpr.isInvalid()) 10381 return ExprError(); 10382 10383 CXXOperatorCallExpr *TheCall = 10384 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 10385 Args, ResultTy, VK, OpLoc, 10386 FPFeatures.fp_contract); 10387 10388 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 10389 FnDecl)) 10390 return ExprError(); 10391 10392 ArrayRef<const Expr *> ArgsArray(Args, 2); 10393 // Cut off the implicit 'this'. 10394 if (isa<CXXMethodDecl>(FnDecl)) 10395 ArgsArray = ArgsArray.slice(1); 10396 checkCall(FnDecl, ArgsArray, 0, isa<CXXMethodDecl>(FnDecl), OpLoc, 10397 TheCall->getSourceRange(), VariadicDoesNotApply); 10398 10399 return MaybeBindToTemporary(TheCall); 10400 } else { 10401 // We matched a built-in operator. Convert the arguments, then 10402 // break out so that we will build the appropriate built-in 10403 // operator node. 10404 ExprResult ArgsRes0 = 10405 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 10406 Best->Conversions[0], AA_Passing); 10407 if (ArgsRes0.isInvalid()) 10408 return ExprError(); 10409 Args[0] = ArgsRes0.take(); 10410 10411 ExprResult ArgsRes1 = 10412 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 10413 Best->Conversions[1], AA_Passing); 10414 if (ArgsRes1.isInvalid()) 10415 return ExprError(); 10416 Args[1] = ArgsRes1.take(); 10417 break; 10418 } 10419 } 10420 10421 case OR_No_Viable_Function: { 10422 // C++ [over.match.oper]p9: 10423 // If the operator is the operator , [...] and there are no 10424 // viable functions, then the operator is assumed to be the 10425 // built-in operator and interpreted according to clause 5. 10426 if (Opc == BO_Comma) 10427 break; 10428 10429 // For class as left operand for assignment or compound assigment 10430 // operator do not fall through to handling in built-in, but report that 10431 // no overloaded assignment operator found 10432 ExprResult Result = ExprError(); 10433 if (Args[0]->getType()->isRecordType() && 10434 Opc >= BO_Assign && Opc <= BO_OrAssign) { 10435 Diag(OpLoc, diag::err_ovl_no_viable_oper) 10436 << BinaryOperator::getOpcodeStr(Opc) 10437 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 10438 } else { 10439 // This is an erroneous use of an operator which can be overloaded by 10440 // a non-member function. Check for non-member operators which were 10441 // defined too late to be candidates. 10442 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, Args)) 10443 // FIXME: Recover by calling the found function. 10444 return ExprError(); 10445 10446 // No viable function; try to create a built-in operation, which will 10447 // produce an error. Then, show the non-viable candidates. 10448 Result = CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 10449 } 10450 assert(Result.isInvalid() && 10451 "C++ binary operator overloading is missing candidates!"); 10452 if (Result.isInvalid()) 10453 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 10454 BinaryOperator::getOpcodeStr(Opc), OpLoc); 10455 return Result; 10456 } 10457 10458 case OR_Ambiguous: 10459 Diag(OpLoc, diag::err_ovl_ambiguous_oper_binary) 10460 << BinaryOperator::getOpcodeStr(Opc) 10461 << Args[0]->getType() << Args[1]->getType() 10462 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 10463 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 10464 BinaryOperator::getOpcodeStr(Opc), OpLoc); 10465 return ExprError(); 10466 10467 case OR_Deleted: 10468 if (isImplicitlyDeleted(Best->Function)) { 10469 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 10470 Diag(OpLoc, diag::err_ovl_deleted_special_oper) 10471 << Context.getRecordType(Method->getParent()) 10472 << getSpecialMember(Method); 10473 10474 // The user probably meant to call this special member. Just 10475 // explain why it's deleted. 10476 NoteDeletedFunction(Method); 10477 return ExprError(); 10478 } else { 10479 Diag(OpLoc, diag::err_ovl_deleted_oper) 10480 << Best->Function->isDeleted() 10481 << BinaryOperator::getOpcodeStr(Opc) 10482 << getDeletedOrUnavailableSuffix(Best->Function) 10483 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 10484 } 10485 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 10486 BinaryOperator::getOpcodeStr(Opc), OpLoc); 10487 return ExprError(); 10488 } 10489 10490 // We matched a built-in operator; build it. 10491 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 10492 } 10493 10494 ExprResult 10495 Sema::CreateOverloadedArraySubscriptExpr(SourceLocation LLoc, 10496 SourceLocation RLoc, 10497 Expr *Base, Expr *Idx) { 10498 Expr *Args[2] = { Base, Idx }; 10499 DeclarationName OpName = 10500 Context.DeclarationNames.getCXXOperatorName(OO_Subscript); 10501 10502 // If either side is type-dependent, create an appropriate dependent 10503 // expression. 10504 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 10505 10506 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 10507 // CHECKME: no 'operator' keyword? 10508 DeclarationNameInfo OpNameInfo(OpName, LLoc); 10509 OpNameInfo.setCXXOperatorNameRange(SourceRange(LLoc, RLoc)); 10510 UnresolvedLookupExpr *Fn 10511 = UnresolvedLookupExpr::Create(Context, NamingClass, 10512 NestedNameSpecifierLoc(), OpNameInfo, 10513 /*ADL*/ true, /*Overloaded*/ false, 10514 UnresolvedSetIterator(), 10515 UnresolvedSetIterator()); 10516 // Can't add any actual overloads yet 10517 10518 return Owned(new (Context) CXXOperatorCallExpr(Context, OO_Subscript, Fn, 10519 Args, 10520 Context.DependentTy, 10521 VK_RValue, 10522 RLoc, false)); 10523 } 10524 10525 // Handle placeholders on both operands. 10526 if (checkPlaceholderForOverload(*this, Args[0])) 10527 return ExprError(); 10528 if (checkPlaceholderForOverload(*this, Args[1])) 10529 return ExprError(); 10530 10531 // Build an empty overload set. 10532 OverloadCandidateSet CandidateSet(LLoc); 10533 10534 // Subscript can only be overloaded as a member function. 10535 10536 // Add operator candidates that are member functions. 10537 AddMemberOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 10538 10539 // Add builtin operator candidates. 10540 AddBuiltinOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 10541 10542 bool HadMultipleCandidates = (CandidateSet.size() > 1); 10543 10544 // Perform overload resolution. 10545 OverloadCandidateSet::iterator Best; 10546 switch (CandidateSet.BestViableFunction(*this, LLoc, Best)) { 10547 case OR_Success: { 10548 // We found a built-in operator or an overloaded operator. 10549 FunctionDecl *FnDecl = Best->Function; 10550 10551 if (FnDecl) { 10552 // We matched an overloaded operator. Build a call to that 10553 // operator. 10554 10555 CheckMemberOperatorAccess(LLoc, Args[0], Args[1], Best->FoundDecl); 10556 10557 // Convert the arguments. 10558 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 10559 ExprResult Arg0 = 10560 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 10561 Best->FoundDecl, Method); 10562 if (Arg0.isInvalid()) 10563 return ExprError(); 10564 Args[0] = Arg0.take(); 10565 10566 // Convert the arguments. 10567 ExprResult InputInit 10568 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 10569 Context, 10570 FnDecl->getParamDecl(0)), 10571 SourceLocation(), 10572 Owned(Args[1])); 10573 if (InputInit.isInvalid()) 10574 return ExprError(); 10575 10576 Args[1] = InputInit.takeAs<Expr>(); 10577 10578 // Determine the result type 10579 QualType ResultTy = FnDecl->getResultType(); 10580 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 10581 ResultTy = ResultTy.getNonLValueExprType(Context); 10582 10583 // Build the actual expression node. 10584 DeclarationNameInfo OpLocInfo(OpName, LLoc); 10585 OpLocInfo.setCXXOperatorNameRange(SourceRange(LLoc, RLoc)); 10586 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, 10587 Best->FoundDecl, 10588 HadMultipleCandidates, 10589 OpLocInfo.getLoc(), 10590 OpLocInfo.getInfo()); 10591 if (FnExpr.isInvalid()) 10592 return ExprError(); 10593 10594 CXXOperatorCallExpr *TheCall = 10595 new (Context) CXXOperatorCallExpr(Context, OO_Subscript, 10596 FnExpr.take(), Args, 10597 ResultTy, VK, RLoc, 10598 false); 10599 10600 if (CheckCallReturnType(FnDecl->getResultType(), LLoc, TheCall, 10601 FnDecl)) 10602 return ExprError(); 10603 10604 return MaybeBindToTemporary(TheCall); 10605 } else { 10606 // We matched a built-in operator. Convert the arguments, then 10607 // break out so that we will build the appropriate built-in 10608 // operator node. 10609 ExprResult ArgsRes0 = 10610 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 10611 Best->Conversions[0], AA_Passing); 10612 if (ArgsRes0.isInvalid()) 10613 return ExprError(); 10614 Args[0] = ArgsRes0.take(); 10615 10616 ExprResult ArgsRes1 = 10617 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 10618 Best->Conversions[1], AA_Passing); 10619 if (ArgsRes1.isInvalid()) 10620 return ExprError(); 10621 Args[1] = ArgsRes1.take(); 10622 10623 break; 10624 } 10625 } 10626 10627 case OR_No_Viable_Function: { 10628 if (CandidateSet.empty()) 10629 Diag(LLoc, diag::err_ovl_no_oper) 10630 << Args[0]->getType() << /*subscript*/ 0 10631 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 10632 else 10633 Diag(LLoc, diag::err_ovl_no_viable_subscript) 10634 << Args[0]->getType() 10635 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 10636 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 10637 "[]", LLoc); 10638 return ExprError(); 10639 } 10640 10641 case OR_Ambiguous: 10642 Diag(LLoc, diag::err_ovl_ambiguous_oper_binary) 10643 << "[]" 10644 << Args[0]->getType() << Args[1]->getType() 10645 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 10646 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 10647 "[]", LLoc); 10648 return ExprError(); 10649 10650 case OR_Deleted: 10651 Diag(LLoc, diag::err_ovl_deleted_oper) 10652 << Best->Function->isDeleted() << "[]" 10653 << getDeletedOrUnavailableSuffix(Best->Function) 10654 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 10655 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 10656 "[]", LLoc); 10657 return ExprError(); 10658 } 10659 10660 // We matched a built-in operator; build it. 10661 return CreateBuiltinArraySubscriptExpr(Args[0], LLoc, Args[1], RLoc); 10662 } 10663 10664 /// BuildCallToMemberFunction - Build a call to a member 10665 /// function. MemExpr is the expression that refers to the member 10666 /// function (and includes the object parameter), Args/NumArgs are the 10667 /// arguments to the function call (not including the object 10668 /// parameter). The caller needs to validate that the member 10669 /// expression refers to a non-static member function or an overloaded 10670 /// member function. 10671 ExprResult 10672 Sema::BuildCallToMemberFunction(Scope *S, Expr *MemExprE, 10673 SourceLocation LParenLoc, Expr **Args, 10674 unsigned NumArgs, SourceLocation RParenLoc) { 10675 assert(MemExprE->getType() == Context.BoundMemberTy || 10676 MemExprE->getType() == Context.OverloadTy); 10677 10678 // Dig out the member expression. This holds both the object 10679 // argument and the member function we're referring to. 10680 Expr *NakedMemExpr = MemExprE->IgnoreParens(); 10681 10682 // Determine whether this is a call to a pointer-to-member function. 10683 if (BinaryOperator *op = dyn_cast<BinaryOperator>(NakedMemExpr)) { 10684 assert(op->getType() == Context.BoundMemberTy); 10685 assert(op->getOpcode() == BO_PtrMemD || op->getOpcode() == BO_PtrMemI); 10686 10687 QualType fnType = 10688 op->getRHS()->getType()->castAs<MemberPointerType>()->getPointeeType(); 10689 10690 const FunctionProtoType *proto = fnType->castAs<FunctionProtoType>(); 10691 QualType resultType = proto->getCallResultType(Context); 10692 ExprValueKind valueKind = Expr::getValueKindForType(proto->getResultType()); 10693 10694 // Check that the object type isn't more qualified than the 10695 // member function we're calling. 10696 Qualifiers funcQuals = Qualifiers::fromCVRMask(proto->getTypeQuals()); 10697 10698 QualType objectType = op->getLHS()->getType(); 10699 if (op->getOpcode() == BO_PtrMemI) 10700 objectType = objectType->castAs<PointerType>()->getPointeeType(); 10701 Qualifiers objectQuals = objectType.getQualifiers(); 10702 10703 Qualifiers difference = objectQuals - funcQuals; 10704 difference.removeObjCGCAttr(); 10705 difference.removeAddressSpace(); 10706 if (difference) { 10707 std::string qualsString = difference.getAsString(); 10708 Diag(LParenLoc, diag::err_pointer_to_member_call_drops_quals) 10709 << fnType.getUnqualifiedType() 10710 << qualsString 10711 << (qualsString.find(' ') == std::string::npos ? 1 : 2); 10712 } 10713 10714 CXXMemberCallExpr *call 10715 = new (Context) CXXMemberCallExpr(Context, MemExprE, 10716 llvm::makeArrayRef(Args, NumArgs), 10717 resultType, valueKind, RParenLoc); 10718 10719 if (CheckCallReturnType(proto->getResultType(), 10720 op->getRHS()->getLocStart(), 10721 call, 0)) 10722 return ExprError(); 10723 10724 if (ConvertArgumentsForCall(call, op, 0, proto, Args, NumArgs, RParenLoc)) 10725 return ExprError(); 10726 10727 return MaybeBindToTemporary(call); 10728 } 10729 10730 UnbridgedCastsSet UnbridgedCasts; 10731 if (checkArgPlaceholdersForOverload(*this, Args, NumArgs, UnbridgedCasts)) 10732 return ExprError(); 10733 10734 MemberExpr *MemExpr; 10735 CXXMethodDecl *Method = 0; 10736 DeclAccessPair FoundDecl = DeclAccessPair::make(0, AS_public); 10737 NestedNameSpecifier *Qualifier = 0; 10738 if (isa<MemberExpr>(NakedMemExpr)) { 10739 MemExpr = cast<MemberExpr>(NakedMemExpr); 10740 Method = cast<CXXMethodDecl>(MemExpr->getMemberDecl()); 10741 FoundDecl = MemExpr->getFoundDecl(); 10742 Qualifier = MemExpr->getQualifier(); 10743 UnbridgedCasts.restore(); 10744 } else { 10745 UnresolvedMemberExpr *UnresExpr = cast<UnresolvedMemberExpr>(NakedMemExpr); 10746 Qualifier = UnresExpr->getQualifier(); 10747 10748 QualType ObjectType = UnresExpr->getBaseType(); 10749 Expr::Classification ObjectClassification 10750 = UnresExpr->isArrow()? Expr::Classification::makeSimpleLValue() 10751 : UnresExpr->getBase()->Classify(Context); 10752 10753 // Add overload candidates 10754 OverloadCandidateSet CandidateSet(UnresExpr->getMemberLoc()); 10755 10756 // FIXME: avoid copy. 10757 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 10758 if (UnresExpr->hasExplicitTemplateArgs()) { 10759 UnresExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 10760 TemplateArgs = &TemplateArgsBuffer; 10761 } 10762 10763 for (UnresolvedMemberExpr::decls_iterator I = UnresExpr->decls_begin(), 10764 E = UnresExpr->decls_end(); I != E; ++I) { 10765 10766 NamedDecl *Func = *I; 10767 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(Func->getDeclContext()); 10768 if (isa<UsingShadowDecl>(Func)) 10769 Func = cast<UsingShadowDecl>(Func)->getTargetDecl(); 10770 10771 10772 // Microsoft supports direct constructor calls. 10773 if (getLangOpts().MicrosoftExt && isa<CXXConstructorDecl>(Func)) { 10774 AddOverloadCandidate(cast<CXXConstructorDecl>(Func), I.getPair(), 10775 llvm::makeArrayRef(Args, NumArgs), CandidateSet); 10776 } else if ((Method = dyn_cast<CXXMethodDecl>(Func))) { 10777 // If explicit template arguments were provided, we can't call a 10778 // non-template member function. 10779 if (TemplateArgs) 10780 continue; 10781 10782 AddMethodCandidate(Method, I.getPair(), ActingDC, ObjectType, 10783 ObjectClassification, 10784 llvm::makeArrayRef(Args, NumArgs), CandidateSet, 10785 /*SuppressUserConversions=*/false); 10786 } else { 10787 AddMethodTemplateCandidate(cast<FunctionTemplateDecl>(Func), 10788 I.getPair(), ActingDC, TemplateArgs, 10789 ObjectType, ObjectClassification, 10790 llvm::makeArrayRef(Args, NumArgs), 10791 CandidateSet, 10792 /*SuppressUsedConversions=*/false); 10793 } 10794 } 10795 10796 DeclarationName DeclName = UnresExpr->getMemberName(); 10797 10798 UnbridgedCasts.restore(); 10799 10800 OverloadCandidateSet::iterator Best; 10801 switch (CandidateSet.BestViableFunction(*this, UnresExpr->getLocStart(), 10802 Best)) { 10803 case OR_Success: 10804 Method = cast<CXXMethodDecl>(Best->Function); 10805 FoundDecl = Best->FoundDecl; 10806 CheckUnresolvedMemberAccess(UnresExpr, Best->FoundDecl); 10807 DiagnoseUseOfDecl(Best->FoundDecl, UnresExpr->getNameLoc()); 10808 break; 10809 10810 case OR_No_Viable_Function: 10811 Diag(UnresExpr->getMemberLoc(), 10812 diag::err_ovl_no_viable_member_function_in_call) 10813 << DeclName << MemExprE->getSourceRange(); 10814 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, 10815 llvm::makeArrayRef(Args, NumArgs)); 10816 // FIXME: Leaking incoming expressions! 10817 return ExprError(); 10818 10819 case OR_Ambiguous: 10820 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_ambiguous_member_call) 10821 << DeclName << MemExprE->getSourceRange(); 10822 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, 10823 llvm::makeArrayRef(Args, NumArgs)); 10824 // FIXME: Leaking incoming expressions! 10825 return ExprError(); 10826 10827 case OR_Deleted: 10828 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_deleted_member_call) 10829 << Best->Function->isDeleted() 10830 << DeclName 10831 << getDeletedOrUnavailableSuffix(Best->Function) 10832 << MemExprE->getSourceRange(); 10833 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, 10834 llvm::makeArrayRef(Args, NumArgs)); 10835 // FIXME: Leaking incoming expressions! 10836 return ExprError(); 10837 } 10838 10839 MemExprE = FixOverloadedFunctionReference(MemExprE, FoundDecl, Method); 10840 10841 // If overload resolution picked a static member, build a 10842 // non-member call based on that function. 10843 if (Method->isStatic()) { 10844 return BuildResolvedCallExpr(MemExprE, Method, LParenLoc, 10845 Args, NumArgs, RParenLoc); 10846 } 10847 10848 MemExpr = cast<MemberExpr>(MemExprE->IgnoreParens()); 10849 } 10850 10851 QualType ResultType = Method->getResultType(); 10852 ExprValueKind VK = Expr::getValueKindForType(ResultType); 10853 ResultType = ResultType.getNonLValueExprType(Context); 10854 10855 assert(Method && "Member call to something that isn't a method?"); 10856 CXXMemberCallExpr *TheCall = 10857 new (Context) CXXMemberCallExpr(Context, MemExprE, 10858 llvm::makeArrayRef(Args, NumArgs), 10859 ResultType, VK, RParenLoc); 10860 10861 // Check for a valid return type. 10862 if (CheckCallReturnType(Method->getResultType(), MemExpr->getMemberLoc(), 10863 TheCall, Method)) 10864 return ExprError(); 10865 10866 // Convert the object argument (for a non-static member function call). 10867 // We only need to do this if there was actually an overload; otherwise 10868 // it was done at lookup. 10869 if (!Method->isStatic()) { 10870 ExprResult ObjectArg = 10871 PerformObjectArgumentInitialization(MemExpr->getBase(), Qualifier, 10872 FoundDecl, Method); 10873 if (ObjectArg.isInvalid()) 10874 return ExprError(); 10875 MemExpr->setBase(ObjectArg.take()); 10876 } 10877 10878 // Convert the rest of the arguments 10879 const FunctionProtoType *Proto = 10880 Method->getType()->getAs<FunctionProtoType>(); 10881 if (ConvertArgumentsForCall(TheCall, MemExpr, Method, Proto, Args, NumArgs, 10882 RParenLoc)) 10883 return ExprError(); 10884 10885 DiagnoseSentinelCalls(Method, LParenLoc, Args, NumArgs); 10886 10887 if (CheckFunctionCall(Method, TheCall, Proto)) 10888 return ExprError(); 10889 10890 if ((isa<CXXConstructorDecl>(CurContext) || 10891 isa<CXXDestructorDecl>(CurContext)) && 10892 TheCall->getMethodDecl()->isPure()) { 10893 const CXXMethodDecl *MD = TheCall->getMethodDecl(); 10894 10895 if (isa<CXXThisExpr>(MemExpr->getBase()->IgnoreParenCasts())) { 10896 Diag(MemExpr->getLocStart(), 10897 diag::warn_call_to_pure_virtual_member_function_from_ctor_dtor) 10898 << MD->getDeclName() << isa<CXXDestructorDecl>(CurContext) 10899 << MD->getParent()->getDeclName(); 10900 10901 Diag(MD->getLocStart(), diag::note_previous_decl) << MD->getDeclName(); 10902 } 10903 } 10904 return MaybeBindToTemporary(TheCall); 10905 } 10906 10907 /// BuildCallToObjectOfClassType - Build a call to an object of class 10908 /// type (C++ [over.call.object]), which can end up invoking an 10909 /// overloaded function call operator (@c operator()) or performing a 10910 /// user-defined conversion on the object argument. 10911 ExprResult 10912 Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj, 10913 SourceLocation LParenLoc, 10914 Expr **Args, unsigned NumArgs, 10915 SourceLocation RParenLoc) { 10916 if (checkPlaceholderForOverload(*this, Obj)) 10917 return ExprError(); 10918 ExprResult Object = Owned(Obj); 10919 10920 UnbridgedCastsSet UnbridgedCasts; 10921 if (checkArgPlaceholdersForOverload(*this, Args, NumArgs, UnbridgedCasts)) 10922 return ExprError(); 10923 10924 assert(Object.get()->getType()->isRecordType() && "Requires object type argument"); 10925 const RecordType *Record = Object.get()->getType()->getAs<RecordType>(); 10926 10927 // C++ [over.call.object]p1: 10928 // If the primary-expression E in the function call syntax 10929 // evaluates to a class object of type "cv T", then the set of 10930 // candidate functions includes at least the function call 10931 // operators of T. The function call operators of T are obtained by 10932 // ordinary lookup of the name operator() in the context of 10933 // (E).operator(). 10934 OverloadCandidateSet CandidateSet(LParenLoc); 10935 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(OO_Call); 10936 10937 if (RequireCompleteType(LParenLoc, Object.get()->getType(), 10938 diag::err_incomplete_object_call, Object.get())) 10939 return true; 10940 10941 LookupResult R(*this, OpName, LParenLoc, LookupOrdinaryName); 10942 LookupQualifiedName(R, Record->getDecl()); 10943 R.suppressDiagnostics(); 10944 10945 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 10946 Oper != OperEnd; ++Oper) { 10947 AddMethodCandidate(Oper.getPair(), Object.get()->getType(), 10948 Object.get()->Classify(Context), Args, NumArgs, CandidateSet, 10949 /*SuppressUserConversions=*/ false); 10950 } 10951 10952 // C++ [over.call.object]p2: 10953 // In addition, for each (non-explicit in C++0x) conversion function 10954 // declared in T of the form 10955 // 10956 // operator conversion-type-id () cv-qualifier; 10957 // 10958 // where cv-qualifier is the same cv-qualification as, or a 10959 // greater cv-qualification than, cv, and where conversion-type-id 10960 // denotes the type "pointer to function of (P1,...,Pn) returning 10961 // R", or the type "reference to pointer to function of 10962 // (P1,...,Pn) returning R", or the type "reference to function 10963 // of (P1,...,Pn) returning R", a surrogate call function [...] 10964 // is also considered as a candidate function. Similarly, 10965 // surrogate call functions are added to the set of candidate 10966 // functions for each conversion function declared in an 10967 // accessible base class provided the function is not hidden 10968 // within T by another intervening declaration. 10969 std::pair<CXXRecordDecl::conversion_iterator, 10970 CXXRecordDecl::conversion_iterator> Conversions 10971 = cast<CXXRecordDecl>(Record->getDecl())->getVisibleConversionFunctions(); 10972 for (CXXRecordDecl::conversion_iterator 10973 I = Conversions.first, E = Conversions.second; I != E; ++I) { 10974 NamedDecl *D = *I; 10975 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 10976 if (isa<UsingShadowDecl>(D)) 10977 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 10978 10979 // Skip over templated conversion functions; they aren't 10980 // surrogates. 10981 if (isa<FunctionTemplateDecl>(D)) 10982 continue; 10983 10984 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 10985 if (!Conv->isExplicit()) { 10986 // Strip the reference type (if any) and then the pointer type (if 10987 // any) to get down to what might be a function type. 10988 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 10989 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 10990 ConvType = ConvPtrType->getPointeeType(); 10991 10992 if (const FunctionProtoType *Proto = ConvType->getAs<FunctionProtoType>()) 10993 { 10994 AddSurrogateCandidate(Conv, I.getPair(), ActingContext, Proto, 10995 Object.get(), llvm::makeArrayRef(Args, NumArgs), 10996 CandidateSet); 10997 } 10998 } 10999 } 11000 11001 bool HadMultipleCandidates = (CandidateSet.size() > 1); 11002 11003 // Perform overload resolution. 11004 OverloadCandidateSet::iterator Best; 11005 switch (CandidateSet.BestViableFunction(*this, Object.get()->getLocStart(), 11006 Best)) { 11007 case OR_Success: 11008 // Overload resolution succeeded; we'll build the appropriate call 11009 // below. 11010 break; 11011 11012 case OR_No_Viable_Function: 11013 if (CandidateSet.empty()) 11014 Diag(Object.get()->getLocStart(), diag::err_ovl_no_oper) 11015 << Object.get()->getType() << /*call*/ 1 11016 << Object.get()->getSourceRange(); 11017 else 11018 Diag(Object.get()->getLocStart(), 11019 diag::err_ovl_no_viable_object_call) 11020 << Object.get()->getType() << Object.get()->getSourceRange(); 11021 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, 11022 llvm::makeArrayRef(Args, NumArgs)); 11023 break; 11024 11025 case OR_Ambiguous: 11026 Diag(Object.get()->getLocStart(), 11027 diag::err_ovl_ambiguous_object_call) 11028 << Object.get()->getType() << Object.get()->getSourceRange(); 11029 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, 11030 llvm::makeArrayRef(Args, NumArgs)); 11031 break; 11032 11033 case OR_Deleted: 11034 Diag(Object.get()->getLocStart(), 11035 diag::err_ovl_deleted_object_call) 11036 << Best->Function->isDeleted() 11037 << Object.get()->getType() 11038 << getDeletedOrUnavailableSuffix(Best->Function) 11039 << Object.get()->getSourceRange(); 11040 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, 11041 llvm::makeArrayRef(Args, NumArgs)); 11042 break; 11043 } 11044 11045 if (Best == CandidateSet.end()) 11046 return true; 11047 11048 UnbridgedCasts.restore(); 11049 11050 if (Best->Function == 0) { 11051 // Since there is no function declaration, this is one of the 11052 // surrogate candidates. Dig out the conversion function. 11053 CXXConversionDecl *Conv 11054 = cast<CXXConversionDecl>( 11055 Best->Conversions[0].UserDefined.ConversionFunction); 11056 11057 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 11058 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 11059 11060 // We selected one of the surrogate functions that converts the 11061 // object parameter to a function pointer. Perform the conversion 11062 // on the object argument, then let ActOnCallExpr finish the job. 11063 11064 // Create an implicit member expr to refer to the conversion operator. 11065 // and then call it. 11066 ExprResult Call = BuildCXXMemberCallExpr(Object.get(), Best->FoundDecl, 11067 Conv, HadMultipleCandidates); 11068 if (Call.isInvalid()) 11069 return ExprError(); 11070 // Record usage of conversion in an implicit cast. 11071 Call = Owned(ImplicitCastExpr::Create(Context, Call.get()->getType(), 11072 CK_UserDefinedConversion, 11073 Call.get(), 0, VK_RValue)); 11074 11075 return ActOnCallExpr(S, Call.get(), LParenLoc, MultiExprArg(Args, NumArgs), 11076 RParenLoc); 11077 } 11078 11079 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 11080 11081 // We found an overloaded operator(). Build a CXXOperatorCallExpr 11082 // that calls this method, using Object for the implicit object 11083 // parameter and passing along the remaining arguments. 11084 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 11085 11086 // An error diagnostic has already been printed when parsing the declaration. 11087 if (Method->isInvalidDecl()) 11088 return ExprError(); 11089 11090 const FunctionProtoType *Proto = 11091 Method->getType()->getAs<FunctionProtoType>(); 11092 11093 unsigned NumArgsInProto = Proto->getNumArgs(); 11094 unsigned NumArgsToCheck = NumArgs; 11095 11096 // Build the full argument list for the method call (the 11097 // implicit object parameter is placed at the beginning of the 11098 // list). 11099 Expr **MethodArgs; 11100 if (NumArgs < NumArgsInProto) { 11101 NumArgsToCheck = NumArgsInProto; 11102 MethodArgs = new Expr*[NumArgsInProto + 1]; 11103 } else { 11104 MethodArgs = new Expr*[NumArgs + 1]; 11105 } 11106 MethodArgs[0] = Object.get(); 11107 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 11108 MethodArgs[ArgIdx + 1] = Args[ArgIdx]; 11109 11110 DeclarationNameInfo OpLocInfo( 11111 Context.DeclarationNames.getCXXOperatorName(OO_Call), LParenLoc); 11112 OpLocInfo.setCXXOperatorNameRange(SourceRange(LParenLoc, RParenLoc)); 11113 ExprResult NewFn = CreateFunctionRefExpr(*this, Method, Best->FoundDecl, 11114 HadMultipleCandidates, 11115 OpLocInfo.getLoc(), 11116 OpLocInfo.getInfo()); 11117 if (NewFn.isInvalid()) 11118 return true; 11119 11120 // Once we've built TheCall, all of the expressions are properly 11121 // owned. 11122 QualType ResultTy = Method->getResultType(); 11123 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 11124 ResultTy = ResultTy.getNonLValueExprType(Context); 11125 11126 CXXOperatorCallExpr *TheCall = 11127 new (Context) CXXOperatorCallExpr(Context, OO_Call, NewFn.take(), 11128 llvm::makeArrayRef(MethodArgs, NumArgs+1), 11129 ResultTy, VK, RParenLoc, false); 11130 delete [] MethodArgs; 11131 11132 if (CheckCallReturnType(Method->getResultType(), LParenLoc, TheCall, 11133 Method)) 11134 return true; 11135 11136 // We may have default arguments. If so, we need to allocate more 11137 // slots in the call for them. 11138 if (NumArgs < NumArgsInProto) 11139 TheCall->setNumArgs(Context, NumArgsInProto + 1); 11140 else if (NumArgs > NumArgsInProto) 11141 NumArgsToCheck = NumArgsInProto; 11142 11143 bool IsError = false; 11144 11145 // Initialize the implicit object parameter. 11146 ExprResult ObjRes = 11147 PerformObjectArgumentInitialization(Object.get(), /*Qualifier=*/0, 11148 Best->FoundDecl, Method); 11149 if (ObjRes.isInvalid()) 11150 IsError = true; 11151 else 11152 Object = ObjRes; 11153 TheCall->setArg(0, Object.take()); 11154 11155 // Check the argument types. 11156 for (unsigned i = 0; i != NumArgsToCheck; i++) { 11157 Expr *Arg; 11158 if (i < NumArgs) { 11159 Arg = Args[i]; 11160 11161 // Pass the argument. 11162 11163 ExprResult InputInit 11164 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 11165 Context, 11166 Method->getParamDecl(i)), 11167 SourceLocation(), Arg); 11168 11169 IsError |= InputInit.isInvalid(); 11170 Arg = InputInit.takeAs<Expr>(); 11171 } else { 11172 ExprResult DefArg 11173 = BuildCXXDefaultArgExpr(LParenLoc, Method, Method->getParamDecl(i)); 11174 if (DefArg.isInvalid()) { 11175 IsError = true; 11176 break; 11177 } 11178 11179 Arg = DefArg.takeAs<Expr>(); 11180 } 11181 11182 TheCall->setArg(i + 1, Arg); 11183 } 11184 11185 // If this is a variadic call, handle args passed through "...". 11186 if (Proto->isVariadic()) { 11187 // Promote the arguments (C99 6.5.2.2p7). 11188 for (unsigned i = NumArgsInProto; i < NumArgs; i++) { 11189 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], VariadicMethod, 0); 11190 IsError |= Arg.isInvalid(); 11191 TheCall->setArg(i + 1, Arg.take()); 11192 } 11193 } 11194 11195 if (IsError) return true; 11196 11197 DiagnoseSentinelCalls(Method, LParenLoc, Args, NumArgs); 11198 11199 if (CheckFunctionCall(Method, TheCall, Proto)) 11200 return true; 11201 11202 return MaybeBindToTemporary(TheCall); 11203 } 11204 11205 /// BuildOverloadedArrowExpr - Build a call to an overloaded @c operator-> 11206 /// (if one exists), where @c Base is an expression of class type and 11207 /// @c Member is the name of the member we're trying to find. 11208 ExprResult 11209 Sema::BuildOverloadedArrowExpr(Scope *S, Expr *Base, SourceLocation OpLoc) { 11210 assert(Base->getType()->isRecordType() && 11211 "left-hand side must have class type"); 11212 11213 if (checkPlaceholderForOverload(*this, Base)) 11214 return ExprError(); 11215 11216 SourceLocation Loc = Base->getExprLoc(); 11217 11218 // C++ [over.ref]p1: 11219 // 11220 // [...] An expression x->m is interpreted as (x.operator->())->m 11221 // for a class object x of type T if T::operator->() exists and if 11222 // the operator is selected as the best match function by the 11223 // overload resolution mechanism (13.3). 11224 DeclarationName OpName = 11225 Context.DeclarationNames.getCXXOperatorName(OO_Arrow); 11226 OverloadCandidateSet CandidateSet(Loc); 11227 const RecordType *BaseRecord = Base->getType()->getAs<RecordType>(); 11228 11229 if (RequireCompleteType(Loc, Base->getType(), 11230 diag::err_typecheck_incomplete_tag, Base)) 11231 return ExprError(); 11232 11233 LookupResult R(*this, OpName, OpLoc, LookupOrdinaryName); 11234 LookupQualifiedName(R, BaseRecord->getDecl()); 11235 R.suppressDiagnostics(); 11236 11237 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 11238 Oper != OperEnd; ++Oper) { 11239 AddMethodCandidate(Oper.getPair(), Base->getType(), Base->Classify(Context), 11240 0, 0, CandidateSet, /*SuppressUserConversions=*/false); 11241 } 11242 11243 bool HadMultipleCandidates = (CandidateSet.size() > 1); 11244 11245 // Perform overload resolution. 11246 OverloadCandidateSet::iterator Best; 11247 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 11248 case OR_Success: 11249 // Overload resolution succeeded; we'll build the call below. 11250 break; 11251 11252 case OR_No_Viable_Function: 11253 if (CandidateSet.empty()) 11254 Diag(OpLoc, diag::err_typecheck_member_reference_arrow) 11255 << Base->getType() << Base->getSourceRange(); 11256 else 11257 Diag(OpLoc, diag::err_ovl_no_viable_oper) 11258 << "operator->" << Base->getSourceRange(); 11259 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Base); 11260 return ExprError(); 11261 11262 case OR_Ambiguous: 11263 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 11264 << "->" << Base->getType() << Base->getSourceRange(); 11265 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Base); 11266 return ExprError(); 11267 11268 case OR_Deleted: 11269 Diag(OpLoc, diag::err_ovl_deleted_oper) 11270 << Best->Function->isDeleted() 11271 << "->" 11272 << getDeletedOrUnavailableSuffix(Best->Function) 11273 << Base->getSourceRange(); 11274 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Base); 11275 return ExprError(); 11276 } 11277 11278 CheckMemberOperatorAccess(OpLoc, Base, 0, Best->FoundDecl); 11279 11280 // Convert the object parameter. 11281 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 11282 ExprResult BaseResult = 11283 PerformObjectArgumentInitialization(Base, /*Qualifier=*/0, 11284 Best->FoundDecl, Method); 11285 if (BaseResult.isInvalid()) 11286 return ExprError(); 11287 Base = BaseResult.take(); 11288 11289 // Build the operator call. 11290 ExprResult FnExpr = CreateFunctionRefExpr(*this, Method, Best->FoundDecl, 11291 HadMultipleCandidates, OpLoc); 11292 if (FnExpr.isInvalid()) 11293 return ExprError(); 11294 11295 QualType ResultTy = Method->getResultType(); 11296 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 11297 ResultTy = ResultTy.getNonLValueExprType(Context); 11298 CXXOperatorCallExpr *TheCall = 11299 new (Context) CXXOperatorCallExpr(Context, OO_Arrow, FnExpr.take(), 11300 Base, ResultTy, VK, OpLoc, false); 11301 11302 if (CheckCallReturnType(Method->getResultType(), OpLoc, TheCall, 11303 Method)) 11304 return ExprError(); 11305 11306 return MaybeBindToTemporary(TheCall); 11307 } 11308 11309 /// BuildLiteralOperatorCall - Build a UserDefinedLiteral by creating a call to 11310 /// a literal operator described by the provided lookup results. 11311 ExprResult Sema::BuildLiteralOperatorCall(LookupResult &R, 11312 DeclarationNameInfo &SuffixInfo, 11313 ArrayRef<Expr*> Args, 11314 SourceLocation LitEndLoc, 11315 TemplateArgumentListInfo *TemplateArgs) { 11316 SourceLocation UDSuffixLoc = SuffixInfo.getCXXLiteralOperatorNameLoc(); 11317 11318 OverloadCandidateSet CandidateSet(UDSuffixLoc); 11319 AddFunctionCandidates(R.asUnresolvedSet(), Args, CandidateSet, true, 11320 TemplateArgs); 11321 11322 bool HadMultipleCandidates = (CandidateSet.size() > 1); 11323 11324 // Perform overload resolution. This will usually be trivial, but might need 11325 // to perform substitutions for a literal operator template. 11326 OverloadCandidateSet::iterator Best; 11327 switch (CandidateSet.BestViableFunction(*this, UDSuffixLoc, Best)) { 11328 case OR_Success: 11329 case OR_Deleted: 11330 break; 11331 11332 case OR_No_Viable_Function: 11333 Diag(UDSuffixLoc, diag::err_ovl_no_viable_function_in_call) 11334 << R.getLookupName(); 11335 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args); 11336 return ExprError(); 11337 11338 case OR_Ambiguous: 11339 Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call) << R.getLookupName(); 11340 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args); 11341 return ExprError(); 11342 } 11343 11344 FunctionDecl *FD = Best->Function; 11345 ExprResult Fn = CreateFunctionRefExpr(*this, FD, Best->FoundDecl, 11346 HadMultipleCandidates, 11347 SuffixInfo.getLoc(), 11348 SuffixInfo.getInfo()); 11349 if (Fn.isInvalid()) 11350 return true; 11351 11352 // Check the argument types. This should almost always be a no-op, except 11353 // that array-to-pointer decay is applied to string literals. 11354 Expr *ConvArgs[2]; 11355 for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) { 11356 ExprResult InputInit = PerformCopyInitialization( 11357 InitializedEntity::InitializeParameter(Context, FD->getParamDecl(ArgIdx)), 11358 SourceLocation(), Args[ArgIdx]); 11359 if (InputInit.isInvalid()) 11360 return true; 11361 ConvArgs[ArgIdx] = InputInit.take(); 11362 } 11363 11364 QualType ResultTy = FD->getResultType(); 11365 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 11366 ResultTy = ResultTy.getNonLValueExprType(Context); 11367 11368 UserDefinedLiteral *UDL = 11369 new (Context) UserDefinedLiteral(Context, Fn.take(), 11370 llvm::makeArrayRef(ConvArgs, Args.size()), 11371 ResultTy, VK, LitEndLoc, UDSuffixLoc); 11372 11373 if (CheckCallReturnType(FD->getResultType(), UDSuffixLoc, UDL, FD)) 11374 return ExprError(); 11375 11376 if (CheckFunctionCall(FD, UDL, NULL)) 11377 return ExprError(); 11378 11379 return MaybeBindToTemporary(UDL); 11380 } 11381 11382 /// Build a call to 'begin' or 'end' for a C++11 for-range statement. If the 11383 /// given LookupResult is non-empty, it is assumed to describe a member which 11384 /// will be invoked. Otherwise, the function will be found via argument 11385 /// dependent lookup. 11386 /// CallExpr is set to a valid expression and FRS_Success returned on success, 11387 /// otherwise CallExpr is set to ExprError() and some non-success value 11388 /// is returned. 11389 Sema::ForRangeStatus 11390 Sema::BuildForRangeBeginEndCall(Scope *S, SourceLocation Loc, 11391 SourceLocation RangeLoc, VarDecl *Decl, 11392 BeginEndFunction BEF, 11393 const DeclarationNameInfo &NameInfo, 11394 LookupResult &MemberLookup, 11395 OverloadCandidateSet *CandidateSet, 11396 Expr *Range, ExprResult *CallExpr) { 11397 CandidateSet->clear(); 11398 if (!MemberLookup.empty()) { 11399 ExprResult MemberRef = 11400 BuildMemberReferenceExpr(Range, Range->getType(), Loc, 11401 /*IsPtr=*/false, CXXScopeSpec(), 11402 /*TemplateKWLoc=*/SourceLocation(), 11403 /*FirstQualifierInScope=*/0, 11404 MemberLookup, 11405 /*TemplateArgs=*/0); 11406 if (MemberRef.isInvalid()) { 11407 *CallExpr = ExprError(); 11408 Diag(Range->getLocStart(), diag::note_in_for_range) 11409 << RangeLoc << BEF << Range->getType(); 11410 return FRS_DiagnosticIssued; 11411 } 11412 *CallExpr = ActOnCallExpr(S, MemberRef.get(), Loc, MultiExprArg(), Loc, 0); 11413 if (CallExpr->isInvalid()) { 11414 *CallExpr = ExprError(); 11415 Diag(Range->getLocStart(), diag::note_in_for_range) 11416 << RangeLoc << BEF << Range->getType(); 11417 return FRS_DiagnosticIssued; 11418 } 11419 } else { 11420 UnresolvedSet<0> FoundNames; 11421 UnresolvedLookupExpr *Fn = 11422 UnresolvedLookupExpr::Create(Context, /*NamingClass=*/0, 11423 NestedNameSpecifierLoc(), NameInfo, 11424 /*NeedsADL=*/true, /*Overloaded=*/false, 11425 FoundNames.begin(), FoundNames.end()); 11426 11427 bool CandidateSetError = buildOverloadedCallSet(S, Fn, Fn, &Range, 1, Loc, 11428 CandidateSet, CallExpr); 11429 if (CandidateSet->empty() || CandidateSetError) { 11430 *CallExpr = ExprError(); 11431 return FRS_NoViableFunction; 11432 } 11433 OverloadCandidateSet::iterator Best; 11434 OverloadingResult OverloadResult = 11435 CandidateSet->BestViableFunction(*this, Fn->getLocStart(), Best); 11436 11437 if (OverloadResult == OR_No_Viable_Function) { 11438 *CallExpr = ExprError(); 11439 return FRS_NoViableFunction; 11440 } 11441 *CallExpr = FinishOverloadedCallExpr(*this, S, Fn, Fn, Loc, &Range, 1, 11442 Loc, 0, CandidateSet, &Best, 11443 OverloadResult, 11444 /*AllowTypoCorrection=*/false); 11445 if (CallExpr->isInvalid() || OverloadResult != OR_Success) { 11446 *CallExpr = ExprError(); 11447 Diag(Range->getLocStart(), diag::note_in_for_range) 11448 << RangeLoc << BEF << Range->getType(); 11449 return FRS_DiagnosticIssued; 11450 } 11451 } 11452 return FRS_Success; 11453 } 11454 11455 11456 /// FixOverloadedFunctionReference - E is an expression that refers to 11457 /// a C++ overloaded function (possibly with some parentheses and 11458 /// perhaps a '&' around it). We have resolved the overloaded function 11459 /// to the function declaration Fn, so patch up the expression E to 11460 /// refer (possibly indirectly) to Fn. Returns the new expr. 11461 Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found, 11462 FunctionDecl *Fn) { 11463 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 11464 Expr *SubExpr = FixOverloadedFunctionReference(PE->getSubExpr(), 11465 Found, Fn); 11466 if (SubExpr == PE->getSubExpr()) 11467 return PE; 11468 11469 return new (Context) ParenExpr(PE->getLParen(), PE->getRParen(), SubExpr); 11470 } 11471 11472 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 11473 Expr *SubExpr = FixOverloadedFunctionReference(ICE->getSubExpr(), 11474 Found, Fn); 11475 assert(Context.hasSameType(ICE->getSubExpr()->getType(), 11476 SubExpr->getType()) && 11477 "Implicit cast type cannot be determined from overload"); 11478 assert(ICE->path_empty() && "fixing up hierarchy conversion?"); 11479 if (SubExpr == ICE->getSubExpr()) 11480 return ICE; 11481 11482 return ImplicitCastExpr::Create(Context, ICE->getType(), 11483 ICE->getCastKind(), 11484 SubExpr, 0, 11485 ICE->getValueKind()); 11486 } 11487 11488 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(E)) { 11489 assert(UnOp->getOpcode() == UO_AddrOf && 11490 "Can only take the address of an overloaded function"); 11491 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 11492 if (Method->isStatic()) { 11493 // Do nothing: static member functions aren't any different 11494 // from non-member functions. 11495 } else { 11496 // Fix the sub expression, which really has to be an 11497 // UnresolvedLookupExpr holding an overloaded member function 11498 // or template. 11499 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 11500 Found, Fn); 11501 if (SubExpr == UnOp->getSubExpr()) 11502 return UnOp; 11503 11504 assert(isa<DeclRefExpr>(SubExpr) 11505 && "fixed to something other than a decl ref"); 11506 assert(cast<DeclRefExpr>(SubExpr)->getQualifier() 11507 && "fixed to a member ref with no nested name qualifier"); 11508 11509 // We have taken the address of a pointer to member 11510 // function. Perform the computation here so that we get the 11511 // appropriate pointer to member type. 11512 QualType ClassType 11513 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 11514 QualType MemPtrType 11515 = Context.getMemberPointerType(Fn->getType(), ClassType.getTypePtr()); 11516 11517 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, MemPtrType, 11518 VK_RValue, OK_Ordinary, 11519 UnOp->getOperatorLoc()); 11520 } 11521 } 11522 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 11523 Found, Fn); 11524 if (SubExpr == UnOp->getSubExpr()) 11525 return UnOp; 11526 11527 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, 11528 Context.getPointerType(SubExpr->getType()), 11529 VK_RValue, OK_Ordinary, 11530 UnOp->getOperatorLoc()); 11531 } 11532 11533 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { 11534 // FIXME: avoid copy. 11535 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 11536 if (ULE->hasExplicitTemplateArgs()) { 11537 ULE->copyTemplateArgumentsInto(TemplateArgsBuffer); 11538 TemplateArgs = &TemplateArgsBuffer; 11539 } 11540 11541 DeclRefExpr *DRE = DeclRefExpr::Create(Context, 11542 ULE->getQualifierLoc(), 11543 ULE->getTemplateKeywordLoc(), 11544 Fn, 11545 /*enclosing*/ false, // FIXME? 11546 ULE->getNameLoc(), 11547 Fn->getType(), 11548 VK_LValue, 11549 Found.getDecl(), 11550 TemplateArgs); 11551 MarkDeclRefReferenced(DRE); 11552 DRE->setHadMultipleCandidates(ULE->getNumDecls() > 1); 11553 return DRE; 11554 } 11555 11556 if (UnresolvedMemberExpr *MemExpr = dyn_cast<UnresolvedMemberExpr>(E)) { 11557 // FIXME: avoid copy. 11558 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 11559 if (MemExpr->hasExplicitTemplateArgs()) { 11560 MemExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 11561 TemplateArgs = &TemplateArgsBuffer; 11562 } 11563 11564 Expr *Base; 11565 11566 // If we're filling in a static method where we used to have an 11567 // implicit member access, rewrite to a simple decl ref. 11568 if (MemExpr->isImplicitAccess()) { 11569 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 11570 DeclRefExpr *DRE = DeclRefExpr::Create(Context, 11571 MemExpr->getQualifierLoc(), 11572 MemExpr->getTemplateKeywordLoc(), 11573 Fn, 11574 /*enclosing*/ false, 11575 MemExpr->getMemberLoc(), 11576 Fn->getType(), 11577 VK_LValue, 11578 Found.getDecl(), 11579 TemplateArgs); 11580 MarkDeclRefReferenced(DRE); 11581 DRE->setHadMultipleCandidates(MemExpr->getNumDecls() > 1); 11582 return DRE; 11583 } else { 11584 SourceLocation Loc = MemExpr->getMemberLoc(); 11585 if (MemExpr->getQualifier()) 11586 Loc = MemExpr->getQualifierLoc().getBeginLoc(); 11587 CheckCXXThisCapture(Loc); 11588 Base = new (Context) CXXThisExpr(Loc, 11589 MemExpr->getBaseType(), 11590 /*isImplicit=*/true); 11591 } 11592 } else 11593 Base = MemExpr->getBase(); 11594 11595 ExprValueKind valueKind; 11596 QualType type; 11597 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 11598 valueKind = VK_LValue; 11599 type = Fn->getType(); 11600 } else { 11601 valueKind = VK_RValue; 11602 type = Context.BoundMemberTy; 11603 } 11604 11605 MemberExpr *ME = MemberExpr::Create(Context, Base, 11606 MemExpr->isArrow(), 11607 MemExpr->getQualifierLoc(), 11608 MemExpr->getTemplateKeywordLoc(), 11609 Fn, 11610 Found, 11611 MemExpr->getMemberNameInfo(), 11612 TemplateArgs, 11613 type, valueKind, OK_Ordinary); 11614 ME->setHadMultipleCandidates(true); 11615 MarkMemberReferenced(ME); 11616 return ME; 11617 } 11618 11619 llvm_unreachable("Invalid reference to overloaded function"); 11620 } 11621 11622 ExprResult Sema::FixOverloadedFunctionReference(ExprResult E, 11623 DeclAccessPair Found, 11624 FunctionDecl *Fn) { 11625 return Owned(FixOverloadedFunctionReference((Expr *)E.get(), Found, Fn)); 11626 } 11627 11628 } // end namespace clang 11629