SemaOverload.cpp revision eb2d1f1c88836bd5382e5d7aa8f6b85148a88b27
1//===--- SemaOverload.cpp - C++ Overloading ---------------------*- C++ -*-===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file provides Sema routines for C++ overloading. 11// 12//===----------------------------------------------------------------------===// 13 14#include "clang/Sema/SemaInternal.h" 15#include "clang/Sema/Lookup.h" 16#include "clang/Sema/Initialization.h" 17#include "clang/Sema/Template.h" 18#include "clang/Sema/TemplateDeduction.h" 19#include "clang/Basic/Diagnostic.h" 20#include "clang/Lex/Preprocessor.h" 21#include "clang/AST/ASTContext.h" 22#include "clang/AST/CXXInheritance.h" 23#include "clang/AST/DeclObjC.h" 24#include "clang/AST/Expr.h" 25#include "clang/AST/ExprCXX.h" 26#include "clang/AST/ExprObjC.h" 27#include "clang/AST/TypeOrdering.h" 28#include "clang/Basic/PartialDiagnostic.h" 29#include "llvm/ADT/DenseSet.h" 30#include "llvm/ADT/SmallPtrSet.h" 31#include "llvm/ADT/STLExtras.h" 32#include <algorithm> 33 34namespace clang { 35using namespace sema; 36 37/// A convenience routine for creating a decayed reference to a 38/// function. 39static ExprResult 40CreateFunctionRefExpr(Sema &S, FunctionDecl *Fn, 41 SourceLocation Loc = SourceLocation(), 42 const DeclarationNameLoc &LocInfo = DeclarationNameLoc()){ 43 ExprResult E = S.Owned(new (S.Context) DeclRefExpr(Fn, Fn->getType(), 44 VK_LValue, Loc, LocInfo)); 45 E = S.DefaultFunctionArrayConversion(E.take()); 46 if (E.isInvalid()) 47 return ExprError(); 48 return move(E); 49} 50 51static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType, 52 bool InOverloadResolution, 53 StandardConversionSequence &SCS, 54 bool CStyle, 55 bool AllowObjCWritebackConversion); 56 57static bool IsTransparentUnionStandardConversion(Sema &S, Expr* From, 58 QualType &ToType, 59 bool InOverloadResolution, 60 StandardConversionSequence &SCS, 61 bool CStyle); 62static OverloadingResult 63IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 64 UserDefinedConversionSequence& User, 65 OverloadCandidateSet& Conversions, 66 bool AllowExplicit); 67 68 69static ImplicitConversionSequence::CompareKind 70CompareStandardConversionSequences(Sema &S, 71 const StandardConversionSequence& SCS1, 72 const StandardConversionSequence& SCS2); 73 74static ImplicitConversionSequence::CompareKind 75CompareQualificationConversions(Sema &S, 76 const StandardConversionSequence& SCS1, 77 const StandardConversionSequence& SCS2); 78 79static ImplicitConversionSequence::CompareKind 80CompareDerivedToBaseConversions(Sema &S, 81 const StandardConversionSequence& SCS1, 82 const StandardConversionSequence& SCS2); 83 84 85 86/// GetConversionCategory - Retrieve the implicit conversion 87/// category corresponding to the given implicit conversion kind. 88ImplicitConversionCategory 89GetConversionCategory(ImplicitConversionKind Kind) { 90 static const ImplicitConversionCategory 91 Category[(int)ICK_Num_Conversion_Kinds] = { 92 ICC_Identity, 93 ICC_Lvalue_Transformation, 94 ICC_Lvalue_Transformation, 95 ICC_Lvalue_Transformation, 96 ICC_Identity, 97 ICC_Qualification_Adjustment, 98 ICC_Promotion, 99 ICC_Promotion, 100 ICC_Promotion, 101 ICC_Conversion, 102 ICC_Conversion, 103 ICC_Conversion, 104 ICC_Conversion, 105 ICC_Conversion, 106 ICC_Conversion, 107 ICC_Conversion, 108 ICC_Conversion, 109 ICC_Conversion, 110 ICC_Conversion, 111 ICC_Conversion, 112 ICC_Conversion, 113 ICC_Conversion 114 }; 115 return Category[(int)Kind]; 116} 117 118/// GetConversionRank - Retrieve the implicit conversion rank 119/// corresponding to the given implicit conversion kind. 120ImplicitConversionRank GetConversionRank(ImplicitConversionKind Kind) { 121 static const ImplicitConversionRank 122 Rank[(int)ICK_Num_Conversion_Kinds] = { 123 ICR_Exact_Match, 124 ICR_Exact_Match, 125 ICR_Exact_Match, 126 ICR_Exact_Match, 127 ICR_Exact_Match, 128 ICR_Exact_Match, 129 ICR_Promotion, 130 ICR_Promotion, 131 ICR_Promotion, 132 ICR_Conversion, 133 ICR_Conversion, 134 ICR_Conversion, 135 ICR_Conversion, 136 ICR_Conversion, 137 ICR_Conversion, 138 ICR_Conversion, 139 ICR_Conversion, 140 ICR_Conversion, 141 ICR_Conversion, 142 ICR_Conversion, 143 ICR_Complex_Real_Conversion, 144 ICR_Conversion, 145 ICR_Conversion, 146 ICR_Writeback_Conversion 147 }; 148 return Rank[(int)Kind]; 149} 150 151/// GetImplicitConversionName - Return the name of this kind of 152/// implicit conversion. 153const char* GetImplicitConversionName(ImplicitConversionKind Kind) { 154 static const char* const Name[(int)ICK_Num_Conversion_Kinds] = { 155 "No conversion", 156 "Lvalue-to-rvalue", 157 "Array-to-pointer", 158 "Function-to-pointer", 159 "Noreturn adjustment", 160 "Qualification", 161 "Integral promotion", 162 "Floating point promotion", 163 "Complex promotion", 164 "Integral conversion", 165 "Floating conversion", 166 "Complex conversion", 167 "Floating-integral conversion", 168 "Pointer conversion", 169 "Pointer-to-member conversion", 170 "Boolean conversion", 171 "Compatible-types conversion", 172 "Derived-to-base conversion", 173 "Vector conversion", 174 "Vector splat", 175 "Complex-real conversion", 176 "Block Pointer conversion", 177 "Transparent Union Conversion" 178 "Writeback conversion" 179 }; 180 return Name[Kind]; 181} 182 183/// StandardConversionSequence - Set the standard conversion 184/// sequence to the identity conversion. 185void StandardConversionSequence::setAsIdentityConversion() { 186 First = ICK_Identity; 187 Second = ICK_Identity; 188 Third = ICK_Identity; 189 DeprecatedStringLiteralToCharPtr = false; 190 QualificationIncludesObjCLifetime = false; 191 ReferenceBinding = false; 192 DirectBinding = false; 193 IsLvalueReference = true; 194 BindsToFunctionLvalue = false; 195 BindsToRvalue = false; 196 BindsImplicitObjectArgumentWithoutRefQualifier = false; 197 ObjCLifetimeConversionBinding = false; 198 CopyConstructor = 0; 199} 200 201/// getRank - Retrieve the rank of this standard conversion sequence 202/// (C++ 13.3.3.1.1p3). The rank is the largest rank of each of the 203/// implicit conversions. 204ImplicitConversionRank StandardConversionSequence::getRank() const { 205 ImplicitConversionRank Rank = ICR_Exact_Match; 206 if (GetConversionRank(First) > Rank) 207 Rank = GetConversionRank(First); 208 if (GetConversionRank(Second) > Rank) 209 Rank = GetConversionRank(Second); 210 if (GetConversionRank(Third) > Rank) 211 Rank = GetConversionRank(Third); 212 return Rank; 213} 214 215/// isPointerConversionToBool - Determines whether this conversion is 216/// a conversion of a pointer or pointer-to-member to bool. This is 217/// used as part of the ranking of standard conversion sequences 218/// (C++ 13.3.3.2p4). 219bool StandardConversionSequence::isPointerConversionToBool() const { 220 // Note that FromType has not necessarily been transformed by the 221 // array-to-pointer or function-to-pointer implicit conversions, so 222 // check for their presence as well as checking whether FromType is 223 // a pointer. 224 if (getToType(1)->isBooleanType() && 225 (getFromType()->isPointerType() || 226 getFromType()->isObjCObjectPointerType() || 227 getFromType()->isBlockPointerType() || 228 getFromType()->isNullPtrType() || 229 First == ICK_Array_To_Pointer || First == ICK_Function_To_Pointer)) 230 return true; 231 232 return false; 233} 234 235/// isPointerConversionToVoidPointer - Determines whether this 236/// conversion is a conversion of a pointer to a void pointer. This is 237/// used as part of the ranking of standard conversion sequences (C++ 238/// 13.3.3.2p4). 239bool 240StandardConversionSequence:: 241isPointerConversionToVoidPointer(ASTContext& Context) const { 242 QualType FromType = getFromType(); 243 QualType ToType = getToType(1); 244 245 // Note that FromType has not necessarily been transformed by the 246 // array-to-pointer implicit conversion, so check for its presence 247 // and redo the conversion to get a pointer. 248 if (First == ICK_Array_To_Pointer) 249 FromType = Context.getArrayDecayedType(FromType); 250 251 if (Second == ICK_Pointer_Conversion && FromType->isAnyPointerType()) 252 if (const PointerType* ToPtrType = ToType->getAs<PointerType>()) 253 return ToPtrType->getPointeeType()->isVoidType(); 254 255 return false; 256} 257 258/// DebugPrint - Print this standard conversion sequence to standard 259/// error. Useful for debugging overloading issues. 260void StandardConversionSequence::DebugPrint() const { 261 raw_ostream &OS = llvm::errs(); 262 bool PrintedSomething = false; 263 if (First != ICK_Identity) { 264 OS << GetImplicitConversionName(First); 265 PrintedSomething = true; 266 } 267 268 if (Second != ICK_Identity) { 269 if (PrintedSomething) { 270 OS << " -> "; 271 } 272 OS << GetImplicitConversionName(Second); 273 274 if (CopyConstructor) { 275 OS << " (by copy constructor)"; 276 } else if (DirectBinding) { 277 OS << " (direct reference binding)"; 278 } else if (ReferenceBinding) { 279 OS << " (reference binding)"; 280 } 281 PrintedSomething = true; 282 } 283 284 if (Third != ICK_Identity) { 285 if (PrintedSomething) { 286 OS << " -> "; 287 } 288 OS << GetImplicitConversionName(Third); 289 PrintedSomething = true; 290 } 291 292 if (!PrintedSomething) { 293 OS << "No conversions required"; 294 } 295} 296 297/// DebugPrint - Print this user-defined conversion sequence to standard 298/// error. Useful for debugging overloading issues. 299void UserDefinedConversionSequence::DebugPrint() const { 300 raw_ostream &OS = llvm::errs(); 301 if (Before.First || Before.Second || Before.Third) { 302 Before.DebugPrint(); 303 OS << " -> "; 304 } 305 OS << '\'' << ConversionFunction << '\''; 306 if (After.First || After.Second || After.Third) { 307 OS << " -> "; 308 After.DebugPrint(); 309 } 310} 311 312/// DebugPrint - Print this implicit conversion sequence to standard 313/// error. Useful for debugging overloading issues. 314void ImplicitConversionSequence::DebugPrint() const { 315 raw_ostream &OS = llvm::errs(); 316 switch (ConversionKind) { 317 case StandardConversion: 318 OS << "Standard conversion: "; 319 Standard.DebugPrint(); 320 break; 321 case UserDefinedConversion: 322 OS << "User-defined conversion: "; 323 UserDefined.DebugPrint(); 324 break; 325 case EllipsisConversion: 326 OS << "Ellipsis conversion"; 327 break; 328 case AmbiguousConversion: 329 OS << "Ambiguous conversion"; 330 break; 331 case BadConversion: 332 OS << "Bad conversion"; 333 break; 334 } 335 336 OS << "\n"; 337} 338 339void AmbiguousConversionSequence::construct() { 340 new (&conversions()) ConversionSet(); 341} 342 343void AmbiguousConversionSequence::destruct() { 344 conversions().~ConversionSet(); 345} 346 347void 348AmbiguousConversionSequence::copyFrom(const AmbiguousConversionSequence &O) { 349 FromTypePtr = O.FromTypePtr; 350 ToTypePtr = O.ToTypePtr; 351 new (&conversions()) ConversionSet(O.conversions()); 352} 353 354namespace { 355 // Structure used by OverloadCandidate::DeductionFailureInfo to store 356 // template parameter and template argument information. 357 struct DFIParamWithArguments { 358 TemplateParameter Param; 359 TemplateArgument FirstArg; 360 TemplateArgument SecondArg; 361 }; 362} 363 364/// \brief Convert from Sema's representation of template deduction information 365/// to the form used in overload-candidate information. 366OverloadCandidate::DeductionFailureInfo 367static MakeDeductionFailureInfo(ASTContext &Context, 368 Sema::TemplateDeductionResult TDK, 369 TemplateDeductionInfo &Info) { 370 OverloadCandidate::DeductionFailureInfo Result; 371 Result.Result = static_cast<unsigned>(TDK); 372 Result.Data = 0; 373 switch (TDK) { 374 case Sema::TDK_Success: 375 case Sema::TDK_InstantiationDepth: 376 case Sema::TDK_TooManyArguments: 377 case Sema::TDK_TooFewArguments: 378 break; 379 380 case Sema::TDK_Incomplete: 381 case Sema::TDK_InvalidExplicitArguments: 382 Result.Data = Info.Param.getOpaqueValue(); 383 break; 384 385 case Sema::TDK_Inconsistent: 386 case Sema::TDK_Underqualified: { 387 // FIXME: Should allocate from normal heap so that we can free this later. 388 DFIParamWithArguments *Saved = new (Context) DFIParamWithArguments; 389 Saved->Param = Info.Param; 390 Saved->FirstArg = Info.FirstArg; 391 Saved->SecondArg = Info.SecondArg; 392 Result.Data = Saved; 393 break; 394 } 395 396 case Sema::TDK_SubstitutionFailure: 397 Result.Data = Info.take(); 398 break; 399 400 case Sema::TDK_NonDeducedMismatch: 401 case Sema::TDK_FailedOverloadResolution: 402 break; 403 } 404 405 return Result; 406} 407 408void OverloadCandidate::DeductionFailureInfo::Destroy() { 409 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 410 case Sema::TDK_Success: 411 case Sema::TDK_InstantiationDepth: 412 case Sema::TDK_Incomplete: 413 case Sema::TDK_TooManyArguments: 414 case Sema::TDK_TooFewArguments: 415 case Sema::TDK_InvalidExplicitArguments: 416 break; 417 418 case Sema::TDK_Inconsistent: 419 case Sema::TDK_Underqualified: 420 // FIXME: Destroy the data? 421 Data = 0; 422 break; 423 424 case Sema::TDK_SubstitutionFailure: 425 // FIXME: Destroy the template arugment list? 426 Data = 0; 427 break; 428 429 // Unhandled 430 case Sema::TDK_NonDeducedMismatch: 431 case Sema::TDK_FailedOverloadResolution: 432 break; 433 } 434} 435 436TemplateParameter 437OverloadCandidate::DeductionFailureInfo::getTemplateParameter() { 438 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 439 case Sema::TDK_Success: 440 case Sema::TDK_InstantiationDepth: 441 case Sema::TDK_TooManyArguments: 442 case Sema::TDK_TooFewArguments: 443 case Sema::TDK_SubstitutionFailure: 444 return TemplateParameter(); 445 446 case Sema::TDK_Incomplete: 447 case Sema::TDK_InvalidExplicitArguments: 448 return TemplateParameter::getFromOpaqueValue(Data); 449 450 case Sema::TDK_Inconsistent: 451 case Sema::TDK_Underqualified: 452 return static_cast<DFIParamWithArguments*>(Data)->Param; 453 454 // Unhandled 455 case Sema::TDK_NonDeducedMismatch: 456 case Sema::TDK_FailedOverloadResolution: 457 break; 458 } 459 460 return TemplateParameter(); 461} 462 463TemplateArgumentList * 464OverloadCandidate::DeductionFailureInfo::getTemplateArgumentList() { 465 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 466 case Sema::TDK_Success: 467 case Sema::TDK_InstantiationDepth: 468 case Sema::TDK_TooManyArguments: 469 case Sema::TDK_TooFewArguments: 470 case Sema::TDK_Incomplete: 471 case Sema::TDK_InvalidExplicitArguments: 472 case Sema::TDK_Inconsistent: 473 case Sema::TDK_Underqualified: 474 return 0; 475 476 case Sema::TDK_SubstitutionFailure: 477 return static_cast<TemplateArgumentList*>(Data); 478 479 // Unhandled 480 case Sema::TDK_NonDeducedMismatch: 481 case Sema::TDK_FailedOverloadResolution: 482 break; 483 } 484 485 return 0; 486} 487 488const TemplateArgument *OverloadCandidate::DeductionFailureInfo::getFirstArg() { 489 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 490 case Sema::TDK_Success: 491 case Sema::TDK_InstantiationDepth: 492 case Sema::TDK_Incomplete: 493 case Sema::TDK_TooManyArguments: 494 case Sema::TDK_TooFewArguments: 495 case Sema::TDK_InvalidExplicitArguments: 496 case Sema::TDK_SubstitutionFailure: 497 return 0; 498 499 case Sema::TDK_Inconsistent: 500 case Sema::TDK_Underqualified: 501 return &static_cast<DFIParamWithArguments*>(Data)->FirstArg; 502 503 // Unhandled 504 case Sema::TDK_NonDeducedMismatch: 505 case Sema::TDK_FailedOverloadResolution: 506 break; 507 } 508 509 return 0; 510} 511 512const TemplateArgument * 513OverloadCandidate::DeductionFailureInfo::getSecondArg() { 514 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 515 case Sema::TDK_Success: 516 case Sema::TDK_InstantiationDepth: 517 case Sema::TDK_Incomplete: 518 case Sema::TDK_TooManyArguments: 519 case Sema::TDK_TooFewArguments: 520 case Sema::TDK_InvalidExplicitArguments: 521 case Sema::TDK_SubstitutionFailure: 522 return 0; 523 524 case Sema::TDK_Inconsistent: 525 case Sema::TDK_Underqualified: 526 return &static_cast<DFIParamWithArguments*>(Data)->SecondArg; 527 528 // Unhandled 529 case Sema::TDK_NonDeducedMismatch: 530 case Sema::TDK_FailedOverloadResolution: 531 break; 532 } 533 534 return 0; 535} 536 537void OverloadCandidateSet::clear() { 538 inherited::clear(); 539 Functions.clear(); 540} 541 542// IsOverload - Determine whether the given New declaration is an 543// overload of the declarations in Old. This routine returns false if 544// New and Old cannot be overloaded, e.g., if New has the same 545// signature as some function in Old (C++ 1.3.10) or if the Old 546// declarations aren't functions (or function templates) at all. When 547// it does return false, MatchedDecl will point to the decl that New 548// cannot be overloaded with. This decl may be a UsingShadowDecl on 549// top of the underlying declaration. 550// 551// Example: Given the following input: 552// 553// void f(int, float); // #1 554// void f(int, int); // #2 555// int f(int, int); // #3 556// 557// When we process #1, there is no previous declaration of "f", 558// so IsOverload will not be used. 559// 560// When we process #2, Old contains only the FunctionDecl for #1. By 561// comparing the parameter types, we see that #1 and #2 are overloaded 562// (since they have different signatures), so this routine returns 563// false; MatchedDecl is unchanged. 564// 565// When we process #3, Old is an overload set containing #1 and #2. We 566// compare the signatures of #3 to #1 (they're overloaded, so we do 567// nothing) and then #3 to #2. Since the signatures of #3 and #2 are 568// identical (return types of functions are not part of the 569// signature), IsOverload returns false and MatchedDecl will be set to 570// point to the FunctionDecl for #2. 571// 572// 'NewIsUsingShadowDecl' indicates that 'New' is being introduced 573// into a class by a using declaration. The rules for whether to hide 574// shadow declarations ignore some properties which otherwise figure 575// into a function template's signature. 576Sema::OverloadKind 577Sema::CheckOverload(Scope *S, FunctionDecl *New, const LookupResult &Old, 578 NamedDecl *&Match, bool NewIsUsingDecl) { 579 for (LookupResult::iterator I = Old.begin(), E = Old.end(); 580 I != E; ++I) { 581 NamedDecl *OldD = *I; 582 583 bool OldIsUsingDecl = false; 584 if (isa<UsingShadowDecl>(OldD)) { 585 OldIsUsingDecl = true; 586 587 // We can always introduce two using declarations into the same 588 // context, even if they have identical signatures. 589 if (NewIsUsingDecl) continue; 590 591 OldD = cast<UsingShadowDecl>(OldD)->getTargetDecl(); 592 } 593 594 // If either declaration was introduced by a using declaration, 595 // we'll need to use slightly different rules for matching. 596 // Essentially, these rules are the normal rules, except that 597 // function templates hide function templates with different 598 // return types or template parameter lists. 599 bool UseMemberUsingDeclRules = 600 (OldIsUsingDecl || NewIsUsingDecl) && CurContext->isRecord(); 601 602 if (FunctionTemplateDecl *OldT = dyn_cast<FunctionTemplateDecl>(OldD)) { 603 if (!IsOverload(New, OldT->getTemplatedDecl(), UseMemberUsingDeclRules)) { 604 if (UseMemberUsingDeclRules && OldIsUsingDecl) { 605 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I)); 606 continue; 607 } 608 609 Match = *I; 610 return Ovl_Match; 611 } 612 } else if (FunctionDecl *OldF = dyn_cast<FunctionDecl>(OldD)) { 613 if (!IsOverload(New, OldF, UseMemberUsingDeclRules)) { 614 if (UseMemberUsingDeclRules && OldIsUsingDecl) { 615 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I)); 616 continue; 617 } 618 619 Match = *I; 620 return Ovl_Match; 621 } 622 } else if (isa<UsingDecl>(OldD)) { 623 // We can overload with these, which can show up when doing 624 // redeclaration checks for UsingDecls. 625 assert(Old.getLookupKind() == LookupUsingDeclName); 626 } else if (isa<TagDecl>(OldD)) { 627 // We can always overload with tags by hiding them. 628 } else if (isa<UnresolvedUsingValueDecl>(OldD)) { 629 // Optimistically assume that an unresolved using decl will 630 // overload; if it doesn't, we'll have to diagnose during 631 // template instantiation. 632 } else { 633 // (C++ 13p1): 634 // Only function declarations can be overloaded; object and type 635 // declarations cannot be overloaded. 636 Match = *I; 637 return Ovl_NonFunction; 638 } 639 } 640 641 return Ovl_Overload; 642} 643 644bool Sema::IsOverload(FunctionDecl *New, FunctionDecl *Old, 645 bool UseUsingDeclRules) { 646 // If both of the functions are extern "C", then they are not 647 // overloads. 648 if (Old->isExternC() && New->isExternC()) 649 return false; 650 651 FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate(); 652 FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate(); 653 654 // C++ [temp.fct]p2: 655 // A function template can be overloaded with other function templates 656 // and with normal (non-template) functions. 657 if ((OldTemplate == 0) != (NewTemplate == 0)) 658 return true; 659 660 // Is the function New an overload of the function Old? 661 QualType OldQType = Context.getCanonicalType(Old->getType()); 662 QualType NewQType = Context.getCanonicalType(New->getType()); 663 664 // Compare the signatures (C++ 1.3.10) of the two functions to 665 // determine whether they are overloads. If we find any mismatch 666 // in the signature, they are overloads. 667 668 // If either of these functions is a K&R-style function (no 669 // prototype), then we consider them to have matching signatures. 670 if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) || 671 isa<FunctionNoProtoType>(NewQType.getTypePtr())) 672 return false; 673 674 const FunctionProtoType* OldType = cast<FunctionProtoType>(OldQType); 675 const FunctionProtoType* NewType = cast<FunctionProtoType>(NewQType); 676 677 // The signature of a function includes the types of its 678 // parameters (C++ 1.3.10), which includes the presence or absence 679 // of the ellipsis; see C++ DR 357). 680 if (OldQType != NewQType && 681 (OldType->getNumArgs() != NewType->getNumArgs() || 682 OldType->isVariadic() != NewType->isVariadic() || 683 !FunctionArgTypesAreEqual(OldType, NewType))) 684 return true; 685 686 // C++ [temp.over.link]p4: 687 // The signature of a function template consists of its function 688 // signature, its return type and its template parameter list. The names 689 // of the template parameters are significant only for establishing the 690 // relationship between the template parameters and the rest of the 691 // signature. 692 // 693 // We check the return type and template parameter lists for function 694 // templates first; the remaining checks follow. 695 // 696 // However, we don't consider either of these when deciding whether 697 // a member introduced by a shadow declaration is hidden. 698 if (!UseUsingDeclRules && NewTemplate && 699 (!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(), 700 OldTemplate->getTemplateParameters(), 701 false, TPL_TemplateMatch) || 702 OldType->getResultType() != NewType->getResultType())) 703 return true; 704 705 // If the function is a class member, its signature includes the 706 // cv-qualifiers (if any) and ref-qualifier (if any) on the function itself. 707 // 708 // As part of this, also check whether one of the member functions 709 // is static, in which case they are not overloads (C++ 710 // 13.1p2). While not part of the definition of the signature, 711 // this check is important to determine whether these functions 712 // can be overloaded. 713 CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 714 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 715 if (OldMethod && NewMethod && 716 !OldMethod->isStatic() && !NewMethod->isStatic() && 717 (OldMethod->getTypeQualifiers() != NewMethod->getTypeQualifiers() || 718 OldMethod->getRefQualifier() != NewMethod->getRefQualifier())) { 719 if (!UseUsingDeclRules && 720 OldMethod->getRefQualifier() != NewMethod->getRefQualifier() && 721 (OldMethod->getRefQualifier() == RQ_None || 722 NewMethod->getRefQualifier() == RQ_None)) { 723 // C++0x [over.load]p2: 724 // - Member function declarations with the same name and the same 725 // parameter-type-list as well as member function template 726 // declarations with the same name, the same parameter-type-list, and 727 // the same template parameter lists cannot be overloaded if any of 728 // them, but not all, have a ref-qualifier (8.3.5). 729 Diag(NewMethod->getLocation(), diag::err_ref_qualifier_overload) 730 << NewMethod->getRefQualifier() << OldMethod->getRefQualifier(); 731 Diag(OldMethod->getLocation(), diag::note_previous_declaration); 732 } 733 734 return true; 735 } 736 737 // The signatures match; this is not an overload. 738 return false; 739} 740 741/// \brief Checks availability of the function depending on the current 742/// function context. Inside an unavailable function, unavailability is ignored. 743/// 744/// \returns true if \arg FD is unavailable and current context is inside 745/// an available function, false otherwise. 746bool Sema::isFunctionConsideredUnavailable(FunctionDecl *FD) { 747 return FD->isUnavailable() && !cast<Decl>(CurContext)->isUnavailable(); 748} 749 750/// TryImplicitConversion - Attempt to perform an implicit conversion 751/// from the given expression (Expr) to the given type (ToType). This 752/// function returns an implicit conversion sequence that can be used 753/// to perform the initialization. Given 754/// 755/// void f(float f); 756/// void g(int i) { f(i); } 757/// 758/// this routine would produce an implicit conversion sequence to 759/// describe the initialization of f from i, which will be a standard 760/// conversion sequence containing an lvalue-to-rvalue conversion (C++ 761/// 4.1) followed by a floating-integral conversion (C++ 4.9). 762// 763/// Note that this routine only determines how the conversion can be 764/// performed; it does not actually perform the conversion. As such, 765/// it will not produce any diagnostics if no conversion is available, 766/// but will instead return an implicit conversion sequence of kind 767/// "BadConversion". 768/// 769/// If @p SuppressUserConversions, then user-defined conversions are 770/// not permitted. 771/// If @p AllowExplicit, then explicit user-defined conversions are 772/// permitted. 773/// 774/// \param AllowObjCWritebackConversion Whether we allow the Objective-C 775/// writeback conversion, which allows __autoreleasing id* parameters to 776/// be initialized with __strong id* or __weak id* arguments. 777static ImplicitConversionSequence 778TryImplicitConversion(Sema &S, Expr *From, QualType ToType, 779 bool SuppressUserConversions, 780 bool AllowExplicit, 781 bool InOverloadResolution, 782 bool CStyle, 783 bool AllowObjCWritebackConversion) { 784 ImplicitConversionSequence ICS; 785 if (IsStandardConversion(S, From, ToType, InOverloadResolution, 786 ICS.Standard, CStyle, AllowObjCWritebackConversion)){ 787 ICS.setStandard(); 788 return ICS; 789 } 790 791 if (!S.getLangOptions().CPlusPlus) { 792 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 793 return ICS; 794 } 795 796 // C++ [over.ics.user]p4: 797 // A conversion of an expression of class type to the same class 798 // type is given Exact Match rank, and a conversion of an 799 // expression of class type to a base class of that type is 800 // given Conversion rank, in spite of the fact that a copy/move 801 // constructor (i.e., a user-defined conversion function) is 802 // called for those cases. 803 QualType FromType = From->getType(); 804 if (ToType->getAs<RecordType>() && FromType->getAs<RecordType>() && 805 (S.Context.hasSameUnqualifiedType(FromType, ToType) || 806 S.IsDerivedFrom(FromType, ToType))) { 807 ICS.setStandard(); 808 ICS.Standard.setAsIdentityConversion(); 809 ICS.Standard.setFromType(FromType); 810 ICS.Standard.setAllToTypes(ToType); 811 812 // We don't actually check at this point whether there is a valid 813 // copy/move constructor, since overloading just assumes that it 814 // exists. When we actually perform initialization, we'll find the 815 // appropriate constructor to copy the returned object, if needed. 816 ICS.Standard.CopyConstructor = 0; 817 818 // Determine whether this is considered a derived-to-base conversion. 819 if (!S.Context.hasSameUnqualifiedType(FromType, ToType)) 820 ICS.Standard.Second = ICK_Derived_To_Base; 821 822 return ICS; 823 } 824 825 if (SuppressUserConversions) { 826 // We're not in the case above, so there is no conversion that 827 // we can perform. 828 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 829 return ICS; 830 } 831 832 // Attempt user-defined conversion. 833 OverloadCandidateSet Conversions(From->getExprLoc()); 834 OverloadingResult UserDefResult 835 = IsUserDefinedConversion(S, From, ToType, ICS.UserDefined, Conversions, 836 AllowExplicit); 837 838 if (UserDefResult == OR_Success) { 839 ICS.setUserDefined(); 840 // C++ [over.ics.user]p4: 841 // A conversion of an expression of class type to the same class 842 // type is given Exact Match rank, and a conversion of an 843 // expression of class type to a base class of that type is 844 // given Conversion rank, in spite of the fact that a copy 845 // constructor (i.e., a user-defined conversion function) is 846 // called for those cases. 847 if (CXXConstructorDecl *Constructor 848 = dyn_cast<CXXConstructorDecl>(ICS.UserDefined.ConversionFunction)) { 849 QualType FromCanon 850 = S.Context.getCanonicalType(From->getType().getUnqualifiedType()); 851 QualType ToCanon 852 = S.Context.getCanonicalType(ToType).getUnqualifiedType(); 853 if (Constructor->isCopyConstructor() && 854 (FromCanon == ToCanon || S.IsDerivedFrom(FromCanon, ToCanon))) { 855 // Turn this into a "standard" conversion sequence, so that it 856 // gets ranked with standard conversion sequences. 857 ICS.setStandard(); 858 ICS.Standard.setAsIdentityConversion(); 859 ICS.Standard.setFromType(From->getType()); 860 ICS.Standard.setAllToTypes(ToType); 861 ICS.Standard.CopyConstructor = Constructor; 862 if (ToCanon != FromCanon) 863 ICS.Standard.Second = ICK_Derived_To_Base; 864 } 865 } 866 867 // C++ [over.best.ics]p4: 868 // However, when considering the argument of a user-defined 869 // conversion function that is a candidate by 13.3.1.3 when 870 // invoked for the copying of the temporary in the second step 871 // of a class copy-initialization, or by 13.3.1.4, 13.3.1.5, or 872 // 13.3.1.6 in all cases, only standard conversion sequences and 873 // ellipsis conversion sequences are allowed. 874 if (SuppressUserConversions && ICS.isUserDefined()) { 875 ICS.setBad(BadConversionSequence::suppressed_user, From, ToType); 876 } 877 } else if (UserDefResult == OR_Ambiguous && !SuppressUserConversions) { 878 ICS.setAmbiguous(); 879 ICS.Ambiguous.setFromType(From->getType()); 880 ICS.Ambiguous.setToType(ToType); 881 for (OverloadCandidateSet::iterator Cand = Conversions.begin(); 882 Cand != Conversions.end(); ++Cand) 883 if (Cand->Viable) 884 ICS.Ambiguous.addConversion(Cand->Function); 885 } else { 886 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 887 } 888 889 return ICS; 890} 891 892ImplicitConversionSequence 893Sema::TryImplicitConversion(Expr *From, QualType ToType, 894 bool SuppressUserConversions, 895 bool AllowExplicit, 896 bool InOverloadResolution, 897 bool CStyle, 898 bool AllowObjCWritebackConversion) { 899 return clang::TryImplicitConversion(*this, From, ToType, 900 SuppressUserConversions, AllowExplicit, 901 InOverloadResolution, CStyle, 902 AllowObjCWritebackConversion); 903} 904 905/// PerformImplicitConversion - Perform an implicit conversion of the 906/// expression From to the type ToType. Returns the 907/// converted expression. Flavor is the kind of conversion we're 908/// performing, used in the error message. If @p AllowExplicit, 909/// explicit user-defined conversions are permitted. 910ExprResult 911Sema::PerformImplicitConversion(Expr *From, QualType ToType, 912 AssignmentAction Action, bool AllowExplicit) { 913 ImplicitConversionSequence ICS; 914 return PerformImplicitConversion(From, ToType, Action, AllowExplicit, ICS); 915} 916 917ExprResult 918Sema::PerformImplicitConversion(Expr *From, QualType ToType, 919 AssignmentAction Action, bool AllowExplicit, 920 ImplicitConversionSequence& ICS) { 921 // Objective-C ARC: Determine whether we will allow the writeback conversion. 922 bool AllowObjCWritebackConversion 923 = getLangOptions().ObjCAutoRefCount && 924 (Action == AA_Passing || Action == AA_Sending); 925 926 927 ICS = clang::TryImplicitConversion(*this, From, ToType, 928 /*SuppressUserConversions=*/false, 929 AllowExplicit, 930 /*InOverloadResolution=*/false, 931 /*CStyle=*/false, 932 AllowObjCWritebackConversion); 933 return PerformImplicitConversion(From, ToType, ICS, Action); 934} 935 936/// \brief Determine whether the conversion from FromType to ToType is a valid 937/// conversion that strips "noreturn" off the nested function type. 938bool Sema::IsNoReturnConversion(QualType FromType, QualType ToType, 939 QualType &ResultTy) { 940 if (Context.hasSameUnqualifiedType(FromType, ToType)) 941 return false; 942 943 // Permit the conversion F(t __attribute__((noreturn))) -> F(t) 944 // where F adds one of the following at most once: 945 // - a pointer 946 // - a member pointer 947 // - a block pointer 948 CanQualType CanTo = Context.getCanonicalType(ToType); 949 CanQualType CanFrom = Context.getCanonicalType(FromType); 950 Type::TypeClass TyClass = CanTo->getTypeClass(); 951 if (TyClass != CanFrom->getTypeClass()) return false; 952 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) { 953 if (TyClass == Type::Pointer) { 954 CanTo = CanTo.getAs<PointerType>()->getPointeeType(); 955 CanFrom = CanFrom.getAs<PointerType>()->getPointeeType(); 956 } else if (TyClass == Type::BlockPointer) { 957 CanTo = CanTo.getAs<BlockPointerType>()->getPointeeType(); 958 CanFrom = CanFrom.getAs<BlockPointerType>()->getPointeeType(); 959 } else if (TyClass == Type::MemberPointer) { 960 CanTo = CanTo.getAs<MemberPointerType>()->getPointeeType(); 961 CanFrom = CanFrom.getAs<MemberPointerType>()->getPointeeType(); 962 } else { 963 return false; 964 } 965 966 TyClass = CanTo->getTypeClass(); 967 if (TyClass != CanFrom->getTypeClass()) return false; 968 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) 969 return false; 970 } 971 972 const FunctionType *FromFn = cast<FunctionType>(CanFrom); 973 FunctionType::ExtInfo EInfo = FromFn->getExtInfo(); 974 if (!EInfo.getNoReturn()) return false; 975 976 FromFn = Context.adjustFunctionType(FromFn, EInfo.withNoReturn(false)); 977 assert(QualType(FromFn, 0).isCanonical()); 978 if (QualType(FromFn, 0) != CanTo) return false; 979 980 ResultTy = ToType; 981 return true; 982} 983 984/// \brief Determine whether the conversion from FromType to ToType is a valid 985/// vector conversion. 986/// 987/// \param ICK Will be set to the vector conversion kind, if this is a vector 988/// conversion. 989static bool IsVectorConversion(ASTContext &Context, QualType FromType, 990 QualType ToType, ImplicitConversionKind &ICK) { 991 // We need at least one of these types to be a vector type to have a vector 992 // conversion. 993 if (!ToType->isVectorType() && !FromType->isVectorType()) 994 return false; 995 996 // Identical types require no conversions. 997 if (Context.hasSameUnqualifiedType(FromType, ToType)) 998 return false; 999 1000 // There are no conversions between extended vector types, only identity. 1001 if (ToType->isExtVectorType()) { 1002 // There are no conversions between extended vector types other than the 1003 // identity conversion. 1004 if (FromType->isExtVectorType()) 1005 return false; 1006 1007 // Vector splat from any arithmetic type to a vector. 1008 if (FromType->isArithmeticType()) { 1009 ICK = ICK_Vector_Splat; 1010 return true; 1011 } 1012 } 1013 1014 // We can perform the conversion between vector types in the following cases: 1015 // 1)vector types are equivalent AltiVec and GCC vector types 1016 // 2)lax vector conversions are permitted and the vector types are of the 1017 // same size 1018 if (ToType->isVectorType() && FromType->isVectorType()) { 1019 if (Context.areCompatibleVectorTypes(FromType, ToType) || 1020 (Context.getLangOptions().LaxVectorConversions && 1021 (Context.getTypeSize(FromType) == Context.getTypeSize(ToType)))) { 1022 ICK = ICK_Vector_Conversion; 1023 return true; 1024 } 1025 } 1026 1027 return false; 1028} 1029 1030/// IsStandardConversion - Determines whether there is a standard 1031/// conversion sequence (C++ [conv], C++ [over.ics.scs]) from the 1032/// expression From to the type ToType. Standard conversion sequences 1033/// only consider non-class types; for conversions that involve class 1034/// types, use TryImplicitConversion. If a conversion exists, SCS will 1035/// contain the standard conversion sequence required to perform this 1036/// conversion and this routine will return true. Otherwise, this 1037/// routine will return false and the value of SCS is unspecified. 1038static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType, 1039 bool InOverloadResolution, 1040 StandardConversionSequence &SCS, 1041 bool CStyle, 1042 bool AllowObjCWritebackConversion) { 1043 QualType FromType = From->getType(); 1044 1045 // Standard conversions (C++ [conv]) 1046 SCS.setAsIdentityConversion(); 1047 SCS.DeprecatedStringLiteralToCharPtr = false; 1048 SCS.IncompatibleObjC = false; 1049 SCS.setFromType(FromType); 1050 SCS.CopyConstructor = 0; 1051 1052 // There are no standard conversions for class types in C++, so 1053 // abort early. When overloading in C, however, we do permit 1054 if (FromType->isRecordType() || ToType->isRecordType()) { 1055 if (S.getLangOptions().CPlusPlus) 1056 return false; 1057 1058 // When we're overloading in C, we allow, as standard conversions, 1059 } 1060 1061 // The first conversion can be an lvalue-to-rvalue conversion, 1062 // array-to-pointer conversion, or function-to-pointer conversion 1063 // (C++ 4p1). 1064 1065 if (FromType == S.Context.OverloadTy) { 1066 DeclAccessPair AccessPair; 1067 if (FunctionDecl *Fn 1068 = S.ResolveAddressOfOverloadedFunction(From, ToType, false, 1069 AccessPair)) { 1070 // We were able to resolve the address of the overloaded function, 1071 // so we can convert to the type of that function. 1072 FromType = Fn->getType(); 1073 1074 // we can sometimes resolve &foo<int> regardless of ToType, so check 1075 // if the type matches (identity) or we are converting to bool 1076 if (!S.Context.hasSameUnqualifiedType( 1077 S.ExtractUnqualifiedFunctionType(ToType), FromType)) { 1078 QualType resultTy; 1079 // if the function type matches except for [[noreturn]], it's ok 1080 if (!S.IsNoReturnConversion(FromType, 1081 S.ExtractUnqualifiedFunctionType(ToType), resultTy)) 1082 // otherwise, only a boolean conversion is standard 1083 if (!ToType->isBooleanType()) 1084 return false; 1085 } 1086 1087 // Check if the "from" expression is taking the address of an overloaded 1088 // function and recompute the FromType accordingly. Take advantage of the 1089 // fact that non-static member functions *must* have such an address-of 1090 // expression. 1091 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn); 1092 if (Method && !Method->isStatic()) { 1093 assert(isa<UnaryOperator>(From->IgnoreParens()) && 1094 "Non-unary operator on non-static member address"); 1095 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() 1096 == UO_AddrOf && 1097 "Non-address-of operator on non-static member address"); 1098 const Type *ClassType 1099 = S.Context.getTypeDeclType(Method->getParent()).getTypePtr(); 1100 FromType = S.Context.getMemberPointerType(FromType, ClassType); 1101 } else if (isa<UnaryOperator>(From->IgnoreParens())) { 1102 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == 1103 UO_AddrOf && 1104 "Non-address-of operator for overloaded function expression"); 1105 FromType = S.Context.getPointerType(FromType); 1106 } 1107 1108 // Check that we've computed the proper type after overload resolution. 1109 assert(S.Context.hasSameType( 1110 FromType, 1111 S.FixOverloadedFunctionReference(From, AccessPair, Fn)->getType())); 1112 } else { 1113 return false; 1114 } 1115 } 1116 // Lvalue-to-rvalue conversion (C++11 4.1): 1117 // A glvalue (3.10) of a non-function, non-array type T can 1118 // be converted to a prvalue. 1119 bool argIsLValue = From->isGLValue(); 1120 if (argIsLValue && 1121 !FromType->isFunctionType() && !FromType->isArrayType() && 1122 S.Context.getCanonicalType(FromType) != S.Context.OverloadTy) { 1123 SCS.First = ICK_Lvalue_To_Rvalue; 1124 1125 // If T is a non-class type, the type of the rvalue is the 1126 // cv-unqualified version of T. Otherwise, the type of the rvalue 1127 // is T (C++ 4.1p1). C++ can't get here with class types; in C, we 1128 // just strip the qualifiers because they don't matter. 1129 FromType = FromType.getUnqualifiedType(); 1130 } else if (FromType->isArrayType()) { 1131 // Array-to-pointer conversion (C++ 4.2) 1132 SCS.First = ICK_Array_To_Pointer; 1133 1134 // An lvalue or rvalue of type "array of N T" or "array of unknown 1135 // bound of T" can be converted to an rvalue of type "pointer to 1136 // T" (C++ 4.2p1). 1137 FromType = S.Context.getArrayDecayedType(FromType); 1138 1139 if (S.IsStringLiteralToNonConstPointerConversion(From, ToType)) { 1140 // This conversion is deprecated. (C++ D.4). 1141 SCS.DeprecatedStringLiteralToCharPtr = true; 1142 1143 // For the purpose of ranking in overload resolution 1144 // (13.3.3.1.1), this conversion is considered an 1145 // array-to-pointer conversion followed by a qualification 1146 // conversion (4.4). (C++ 4.2p2) 1147 SCS.Second = ICK_Identity; 1148 SCS.Third = ICK_Qualification; 1149 SCS.QualificationIncludesObjCLifetime = false; 1150 SCS.setAllToTypes(FromType); 1151 return true; 1152 } 1153 } else if (FromType->isFunctionType() && argIsLValue) { 1154 // Function-to-pointer conversion (C++ 4.3). 1155 SCS.First = ICK_Function_To_Pointer; 1156 1157 // An lvalue of function type T can be converted to an rvalue of 1158 // type "pointer to T." The result is a pointer to the 1159 // function. (C++ 4.3p1). 1160 FromType = S.Context.getPointerType(FromType); 1161 } else { 1162 // We don't require any conversions for the first step. 1163 SCS.First = ICK_Identity; 1164 } 1165 SCS.setToType(0, FromType); 1166 1167 // The second conversion can be an integral promotion, floating 1168 // point promotion, integral conversion, floating point conversion, 1169 // floating-integral conversion, pointer conversion, 1170 // pointer-to-member conversion, or boolean conversion (C++ 4p1). 1171 // For overloading in C, this can also be a "compatible-type" 1172 // conversion. 1173 bool IncompatibleObjC = false; 1174 ImplicitConversionKind SecondICK = ICK_Identity; 1175 if (S.Context.hasSameUnqualifiedType(FromType, ToType)) { 1176 // The unqualified versions of the types are the same: there's no 1177 // conversion to do. 1178 SCS.Second = ICK_Identity; 1179 } else if (S.IsIntegralPromotion(From, FromType, ToType)) { 1180 // Integral promotion (C++ 4.5). 1181 SCS.Second = ICK_Integral_Promotion; 1182 FromType = ToType.getUnqualifiedType(); 1183 } else if (S.IsFloatingPointPromotion(FromType, ToType)) { 1184 // Floating point promotion (C++ 4.6). 1185 SCS.Second = ICK_Floating_Promotion; 1186 FromType = ToType.getUnqualifiedType(); 1187 } else if (S.IsComplexPromotion(FromType, ToType)) { 1188 // Complex promotion (Clang extension) 1189 SCS.Second = ICK_Complex_Promotion; 1190 FromType = ToType.getUnqualifiedType(); 1191 } else if (ToType->isBooleanType() && 1192 (FromType->isArithmeticType() || 1193 FromType->isAnyPointerType() || 1194 FromType->isBlockPointerType() || 1195 FromType->isMemberPointerType() || 1196 FromType->isNullPtrType())) { 1197 // Boolean conversions (C++ 4.12). 1198 SCS.Second = ICK_Boolean_Conversion; 1199 FromType = S.Context.BoolTy; 1200 } else if (FromType->isIntegralOrUnscopedEnumerationType() && 1201 ToType->isIntegralType(S.Context)) { 1202 // Integral conversions (C++ 4.7). 1203 SCS.Second = ICK_Integral_Conversion; 1204 FromType = ToType.getUnqualifiedType(); 1205 } else if (FromType->isAnyComplexType() && ToType->isComplexType()) { 1206 // Complex conversions (C99 6.3.1.6) 1207 SCS.Second = ICK_Complex_Conversion; 1208 FromType = ToType.getUnqualifiedType(); 1209 } else if ((FromType->isAnyComplexType() && ToType->isArithmeticType()) || 1210 (ToType->isAnyComplexType() && FromType->isArithmeticType())) { 1211 // Complex-real conversions (C99 6.3.1.7) 1212 SCS.Second = ICK_Complex_Real; 1213 FromType = ToType.getUnqualifiedType(); 1214 } else if (FromType->isRealFloatingType() && ToType->isRealFloatingType()) { 1215 // Floating point conversions (C++ 4.8). 1216 SCS.Second = ICK_Floating_Conversion; 1217 FromType = ToType.getUnqualifiedType(); 1218 } else if ((FromType->isRealFloatingType() && 1219 ToType->isIntegralType(S.Context)) || 1220 (FromType->isIntegralOrUnscopedEnumerationType() && 1221 ToType->isRealFloatingType())) { 1222 // Floating-integral conversions (C++ 4.9). 1223 SCS.Second = ICK_Floating_Integral; 1224 FromType = ToType.getUnqualifiedType(); 1225 } else if (S.IsBlockPointerConversion(FromType, ToType, FromType)) { 1226 SCS.Second = ICK_Block_Pointer_Conversion; 1227 } else if (AllowObjCWritebackConversion && 1228 S.isObjCWritebackConversion(FromType, ToType, FromType)) { 1229 SCS.Second = ICK_Writeback_Conversion; 1230 } else if (S.IsPointerConversion(From, FromType, ToType, InOverloadResolution, 1231 FromType, IncompatibleObjC)) { 1232 // Pointer conversions (C++ 4.10). 1233 SCS.Second = ICK_Pointer_Conversion; 1234 SCS.IncompatibleObjC = IncompatibleObjC; 1235 FromType = FromType.getUnqualifiedType(); 1236 } else if (S.IsMemberPointerConversion(From, FromType, ToType, 1237 InOverloadResolution, FromType)) { 1238 // Pointer to member conversions (4.11). 1239 SCS.Second = ICK_Pointer_Member; 1240 } else if (IsVectorConversion(S.Context, FromType, ToType, SecondICK)) { 1241 SCS.Second = SecondICK; 1242 FromType = ToType.getUnqualifiedType(); 1243 } else if (!S.getLangOptions().CPlusPlus && 1244 S.Context.typesAreCompatible(ToType, FromType)) { 1245 // Compatible conversions (Clang extension for C function overloading) 1246 SCS.Second = ICK_Compatible_Conversion; 1247 FromType = ToType.getUnqualifiedType(); 1248 } else if (S.IsNoReturnConversion(FromType, ToType, FromType)) { 1249 // Treat a conversion that strips "noreturn" as an identity conversion. 1250 SCS.Second = ICK_NoReturn_Adjustment; 1251 } else if (IsTransparentUnionStandardConversion(S, From, ToType, 1252 InOverloadResolution, 1253 SCS, CStyle)) { 1254 SCS.Second = ICK_TransparentUnionConversion; 1255 FromType = ToType; 1256 } else { 1257 // No second conversion required. 1258 SCS.Second = ICK_Identity; 1259 } 1260 SCS.setToType(1, FromType); 1261 1262 QualType CanonFrom; 1263 QualType CanonTo; 1264 // The third conversion can be a qualification conversion (C++ 4p1). 1265 bool ObjCLifetimeConversion; 1266 if (S.IsQualificationConversion(FromType, ToType, CStyle, 1267 ObjCLifetimeConversion)) { 1268 SCS.Third = ICK_Qualification; 1269 SCS.QualificationIncludesObjCLifetime = ObjCLifetimeConversion; 1270 FromType = ToType; 1271 CanonFrom = S.Context.getCanonicalType(FromType); 1272 CanonTo = S.Context.getCanonicalType(ToType); 1273 } else { 1274 // No conversion required 1275 SCS.Third = ICK_Identity; 1276 1277 // C++ [over.best.ics]p6: 1278 // [...] Any difference in top-level cv-qualification is 1279 // subsumed by the initialization itself and does not constitute 1280 // a conversion. [...] 1281 CanonFrom = S.Context.getCanonicalType(FromType); 1282 CanonTo = S.Context.getCanonicalType(ToType); 1283 if (CanonFrom.getLocalUnqualifiedType() 1284 == CanonTo.getLocalUnqualifiedType() && 1285 (CanonFrom.getLocalCVRQualifiers() != CanonTo.getLocalCVRQualifiers() 1286 || CanonFrom.getObjCGCAttr() != CanonTo.getObjCGCAttr() 1287 || CanonFrom.getObjCLifetime() != CanonTo.getObjCLifetime())) { 1288 FromType = ToType; 1289 CanonFrom = CanonTo; 1290 } 1291 } 1292 SCS.setToType(2, FromType); 1293 1294 // If we have not converted the argument type to the parameter type, 1295 // this is a bad conversion sequence. 1296 if (CanonFrom != CanonTo) 1297 return false; 1298 1299 return true; 1300} 1301 1302static bool 1303IsTransparentUnionStandardConversion(Sema &S, Expr* From, 1304 QualType &ToType, 1305 bool InOverloadResolution, 1306 StandardConversionSequence &SCS, 1307 bool CStyle) { 1308 1309 const RecordType *UT = ToType->getAsUnionType(); 1310 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 1311 return false; 1312 // The field to initialize within the transparent union. 1313 RecordDecl *UD = UT->getDecl(); 1314 // It's compatible if the expression matches any of the fields. 1315 for (RecordDecl::field_iterator it = UD->field_begin(), 1316 itend = UD->field_end(); 1317 it != itend; ++it) { 1318 if (IsStandardConversion(S, From, it->getType(), InOverloadResolution, SCS, 1319 CStyle, /*ObjCWritebackConversion=*/false)) { 1320 ToType = it->getType(); 1321 return true; 1322 } 1323 } 1324 return false; 1325} 1326 1327/// IsIntegralPromotion - Determines whether the conversion from the 1328/// expression From (whose potentially-adjusted type is FromType) to 1329/// ToType is an integral promotion (C++ 4.5). If so, returns true and 1330/// sets PromotedType to the promoted type. 1331bool Sema::IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType) { 1332 const BuiltinType *To = ToType->getAs<BuiltinType>(); 1333 // All integers are built-in. 1334 if (!To) { 1335 return false; 1336 } 1337 1338 // An rvalue of type char, signed char, unsigned char, short int, or 1339 // unsigned short int can be converted to an rvalue of type int if 1340 // int can represent all the values of the source type; otherwise, 1341 // the source rvalue can be converted to an rvalue of type unsigned 1342 // int (C++ 4.5p1). 1343 if (FromType->isPromotableIntegerType() && !FromType->isBooleanType() && 1344 !FromType->isEnumeralType()) { 1345 if (// We can promote any signed, promotable integer type to an int 1346 (FromType->isSignedIntegerType() || 1347 // We can promote any unsigned integer type whose size is 1348 // less than int to an int. 1349 (!FromType->isSignedIntegerType() && 1350 Context.getTypeSize(FromType) < Context.getTypeSize(ToType)))) { 1351 return To->getKind() == BuiltinType::Int; 1352 } 1353 1354 return To->getKind() == BuiltinType::UInt; 1355 } 1356 1357 // C++0x [conv.prom]p3: 1358 // A prvalue of an unscoped enumeration type whose underlying type is not 1359 // fixed (7.2) can be converted to an rvalue a prvalue of the first of the 1360 // following types that can represent all the values of the enumeration 1361 // (i.e., the values in the range bmin to bmax as described in 7.2): int, 1362 // unsigned int, long int, unsigned long int, long long int, or unsigned 1363 // long long int. If none of the types in that list can represent all the 1364 // values of the enumeration, an rvalue a prvalue of an unscoped enumeration 1365 // type can be converted to an rvalue a prvalue of the extended integer type 1366 // with lowest integer conversion rank (4.13) greater than the rank of long 1367 // long in which all the values of the enumeration can be represented. If 1368 // there are two such extended types, the signed one is chosen. 1369 if (const EnumType *FromEnumType = FromType->getAs<EnumType>()) { 1370 // C++0x 7.2p9: Note that this implicit enum to int conversion is not 1371 // provided for a scoped enumeration. 1372 if (FromEnumType->getDecl()->isScoped()) 1373 return false; 1374 1375 // We have already pre-calculated the promotion type, so this is trivial. 1376 if (ToType->isIntegerType() && 1377 !RequireCompleteType(From->getLocStart(), FromType, PDiag())) 1378 return Context.hasSameUnqualifiedType(ToType, 1379 FromEnumType->getDecl()->getPromotionType()); 1380 } 1381 1382 // C++0x [conv.prom]p2: 1383 // A prvalue of type char16_t, char32_t, or wchar_t (3.9.1) can be converted 1384 // to an rvalue a prvalue of the first of the following types that can 1385 // represent all the values of its underlying type: int, unsigned int, 1386 // long int, unsigned long int, long long int, or unsigned long long int. 1387 // If none of the types in that list can represent all the values of its 1388 // underlying type, an rvalue a prvalue of type char16_t, char32_t, 1389 // or wchar_t can be converted to an rvalue a prvalue of its underlying 1390 // type. 1391 if (FromType->isAnyCharacterType() && !FromType->isCharType() && 1392 ToType->isIntegerType()) { 1393 // Determine whether the type we're converting from is signed or 1394 // unsigned. 1395 bool FromIsSigned = FromType->isSignedIntegerType(); 1396 uint64_t FromSize = Context.getTypeSize(FromType); 1397 1398 // The types we'll try to promote to, in the appropriate 1399 // order. Try each of these types. 1400 QualType PromoteTypes[6] = { 1401 Context.IntTy, Context.UnsignedIntTy, 1402 Context.LongTy, Context.UnsignedLongTy , 1403 Context.LongLongTy, Context.UnsignedLongLongTy 1404 }; 1405 for (int Idx = 0; Idx < 6; ++Idx) { 1406 uint64_t ToSize = Context.getTypeSize(PromoteTypes[Idx]); 1407 if (FromSize < ToSize || 1408 (FromSize == ToSize && 1409 FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType())) { 1410 // We found the type that we can promote to. If this is the 1411 // type we wanted, we have a promotion. Otherwise, no 1412 // promotion. 1413 return Context.hasSameUnqualifiedType(ToType, PromoteTypes[Idx]); 1414 } 1415 } 1416 } 1417 1418 // An rvalue for an integral bit-field (9.6) can be converted to an 1419 // rvalue of type int if int can represent all the values of the 1420 // bit-field; otherwise, it can be converted to unsigned int if 1421 // unsigned int can represent all the values of the bit-field. If 1422 // the bit-field is larger yet, no integral promotion applies to 1423 // it. If the bit-field has an enumerated type, it is treated as any 1424 // other value of that type for promotion purposes (C++ 4.5p3). 1425 // FIXME: We should delay checking of bit-fields until we actually perform the 1426 // conversion. 1427 using llvm::APSInt; 1428 if (From) 1429 if (FieldDecl *MemberDecl = From->getBitField()) { 1430 APSInt BitWidth; 1431 if (FromType->isIntegralType(Context) && 1432 MemberDecl->getBitWidth()->isIntegerConstantExpr(BitWidth, Context)) { 1433 APSInt ToSize(BitWidth.getBitWidth(), BitWidth.isUnsigned()); 1434 ToSize = Context.getTypeSize(ToType); 1435 1436 // Are we promoting to an int from a bitfield that fits in an int? 1437 if (BitWidth < ToSize || 1438 (FromType->isSignedIntegerType() && BitWidth <= ToSize)) { 1439 return To->getKind() == BuiltinType::Int; 1440 } 1441 1442 // Are we promoting to an unsigned int from an unsigned bitfield 1443 // that fits into an unsigned int? 1444 if (FromType->isUnsignedIntegerType() && BitWidth <= ToSize) { 1445 return To->getKind() == BuiltinType::UInt; 1446 } 1447 1448 return false; 1449 } 1450 } 1451 1452 // An rvalue of type bool can be converted to an rvalue of type int, 1453 // with false becoming zero and true becoming one (C++ 4.5p4). 1454 if (FromType->isBooleanType() && To->getKind() == BuiltinType::Int) { 1455 return true; 1456 } 1457 1458 return false; 1459} 1460 1461/// IsFloatingPointPromotion - Determines whether the conversion from 1462/// FromType to ToType is a floating point promotion (C++ 4.6). If so, 1463/// returns true and sets PromotedType to the promoted type. 1464bool Sema::IsFloatingPointPromotion(QualType FromType, QualType ToType) { 1465 /// An rvalue of type float can be converted to an rvalue of type 1466 /// double. (C++ 4.6p1). 1467 if (const BuiltinType *FromBuiltin = FromType->getAs<BuiltinType>()) 1468 if (const BuiltinType *ToBuiltin = ToType->getAs<BuiltinType>()) { 1469 if (FromBuiltin->getKind() == BuiltinType::Float && 1470 ToBuiltin->getKind() == BuiltinType::Double) 1471 return true; 1472 1473 // C99 6.3.1.5p1: 1474 // When a float is promoted to double or long double, or a 1475 // double is promoted to long double [...]. 1476 if (!getLangOptions().CPlusPlus && 1477 (FromBuiltin->getKind() == BuiltinType::Float || 1478 FromBuiltin->getKind() == BuiltinType::Double) && 1479 (ToBuiltin->getKind() == BuiltinType::LongDouble)) 1480 return true; 1481 } 1482 1483 return false; 1484} 1485 1486/// \brief Determine if a conversion is a complex promotion. 1487/// 1488/// A complex promotion is defined as a complex -> complex conversion 1489/// where the conversion between the underlying real types is a 1490/// floating-point or integral promotion. 1491bool Sema::IsComplexPromotion(QualType FromType, QualType ToType) { 1492 const ComplexType *FromComplex = FromType->getAs<ComplexType>(); 1493 if (!FromComplex) 1494 return false; 1495 1496 const ComplexType *ToComplex = ToType->getAs<ComplexType>(); 1497 if (!ToComplex) 1498 return false; 1499 1500 return IsFloatingPointPromotion(FromComplex->getElementType(), 1501 ToComplex->getElementType()) || 1502 IsIntegralPromotion(0, FromComplex->getElementType(), 1503 ToComplex->getElementType()); 1504} 1505 1506/// BuildSimilarlyQualifiedPointerType - In a pointer conversion from 1507/// the pointer type FromPtr to a pointer to type ToPointee, with the 1508/// same type qualifiers as FromPtr has on its pointee type. ToType, 1509/// if non-empty, will be a pointer to ToType that may or may not have 1510/// the right set of qualifiers on its pointee. 1511/// 1512static QualType 1513BuildSimilarlyQualifiedPointerType(const Type *FromPtr, 1514 QualType ToPointee, QualType ToType, 1515 ASTContext &Context, 1516 bool StripObjCLifetime = false) { 1517 assert((FromPtr->getTypeClass() == Type::Pointer || 1518 FromPtr->getTypeClass() == Type::ObjCObjectPointer) && 1519 "Invalid similarly-qualified pointer type"); 1520 1521 /// Conversions to 'id' subsume cv-qualifier conversions. 1522 if (ToType->isObjCIdType() || ToType->isObjCQualifiedIdType()) 1523 return ToType.getUnqualifiedType(); 1524 1525 QualType CanonFromPointee 1526 = Context.getCanonicalType(FromPtr->getPointeeType()); 1527 QualType CanonToPointee = Context.getCanonicalType(ToPointee); 1528 Qualifiers Quals = CanonFromPointee.getQualifiers(); 1529 1530 if (StripObjCLifetime) 1531 Quals.removeObjCLifetime(); 1532 1533 // Exact qualifier match -> return the pointer type we're converting to. 1534 if (CanonToPointee.getLocalQualifiers() == Quals) { 1535 // ToType is exactly what we need. Return it. 1536 if (!ToType.isNull()) 1537 return ToType.getUnqualifiedType(); 1538 1539 // Build a pointer to ToPointee. It has the right qualifiers 1540 // already. 1541 if (isa<ObjCObjectPointerType>(ToType)) 1542 return Context.getObjCObjectPointerType(ToPointee); 1543 return Context.getPointerType(ToPointee); 1544 } 1545 1546 // Just build a canonical type that has the right qualifiers. 1547 QualType QualifiedCanonToPointee 1548 = Context.getQualifiedType(CanonToPointee.getLocalUnqualifiedType(), Quals); 1549 1550 if (isa<ObjCObjectPointerType>(ToType)) 1551 return Context.getObjCObjectPointerType(QualifiedCanonToPointee); 1552 return Context.getPointerType(QualifiedCanonToPointee); 1553} 1554 1555static bool isNullPointerConstantForConversion(Expr *Expr, 1556 bool InOverloadResolution, 1557 ASTContext &Context) { 1558 // Handle value-dependent integral null pointer constants correctly. 1559 // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#903 1560 if (Expr->isValueDependent() && !Expr->isTypeDependent() && 1561 Expr->getType()->isIntegerType() && !Expr->getType()->isEnumeralType()) 1562 return !InOverloadResolution; 1563 1564 return Expr->isNullPointerConstant(Context, 1565 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 1566 : Expr::NPC_ValueDependentIsNull); 1567} 1568 1569/// IsPointerConversion - Determines whether the conversion of the 1570/// expression From, which has the (possibly adjusted) type FromType, 1571/// can be converted to the type ToType via a pointer conversion (C++ 1572/// 4.10). If so, returns true and places the converted type (that 1573/// might differ from ToType in its cv-qualifiers at some level) into 1574/// ConvertedType. 1575/// 1576/// This routine also supports conversions to and from block pointers 1577/// and conversions with Objective-C's 'id', 'id<protocols...>', and 1578/// pointers to interfaces. FIXME: Once we've determined the 1579/// appropriate overloading rules for Objective-C, we may want to 1580/// split the Objective-C checks into a different routine; however, 1581/// GCC seems to consider all of these conversions to be pointer 1582/// conversions, so for now they live here. IncompatibleObjC will be 1583/// set if the conversion is an allowed Objective-C conversion that 1584/// should result in a warning. 1585bool Sema::IsPointerConversion(Expr *From, QualType FromType, QualType ToType, 1586 bool InOverloadResolution, 1587 QualType& ConvertedType, 1588 bool &IncompatibleObjC) { 1589 IncompatibleObjC = false; 1590 if (isObjCPointerConversion(FromType, ToType, ConvertedType, 1591 IncompatibleObjC)) 1592 return true; 1593 1594 // Conversion from a null pointer constant to any Objective-C pointer type. 1595 if (ToType->isObjCObjectPointerType() && 1596 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1597 ConvertedType = ToType; 1598 return true; 1599 } 1600 1601 // Blocks: Block pointers can be converted to void*. 1602 if (FromType->isBlockPointerType() && ToType->isPointerType() && 1603 ToType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 1604 ConvertedType = ToType; 1605 return true; 1606 } 1607 // Blocks: A null pointer constant can be converted to a block 1608 // pointer type. 1609 if (ToType->isBlockPointerType() && 1610 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1611 ConvertedType = ToType; 1612 return true; 1613 } 1614 1615 // If the left-hand-side is nullptr_t, the right side can be a null 1616 // pointer constant. 1617 if (ToType->isNullPtrType() && 1618 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1619 ConvertedType = ToType; 1620 return true; 1621 } 1622 1623 const PointerType* ToTypePtr = ToType->getAs<PointerType>(); 1624 if (!ToTypePtr) 1625 return false; 1626 1627 // A null pointer constant can be converted to a pointer type (C++ 4.10p1). 1628 if (isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1629 ConvertedType = ToType; 1630 return true; 1631 } 1632 1633 // Beyond this point, both types need to be pointers 1634 // , including objective-c pointers. 1635 QualType ToPointeeType = ToTypePtr->getPointeeType(); 1636 if (FromType->isObjCObjectPointerType() && ToPointeeType->isVoidType() && 1637 !getLangOptions().ObjCAutoRefCount) { 1638 ConvertedType = BuildSimilarlyQualifiedPointerType( 1639 FromType->getAs<ObjCObjectPointerType>(), 1640 ToPointeeType, 1641 ToType, Context); 1642 return true; 1643 } 1644 const PointerType *FromTypePtr = FromType->getAs<PointerType>(); 1645 if (!FromTypePtr) 1646 return false; 1647 1648 QualType FromPointeeType = FromTypePtr->getPointeeType(); 1649 1650 // If the unqualified pointee types are the same, this can't be a 1651 // pointer conversion, so don't do all of the work below. 1652 if (Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) 1653 return false; 1654 1655 // An rvalue of type "pointer to cv T," where T is an object type, 1656 // can be converted to an rvalue of type "pointer to cv void" (C++ 1657 // 4.10p2). 1658 if (FromPointeeType->isIncompleteOrObjectType() && 1659 ToPointeeType->isVoidType()) { 1660 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1661 ToPointeeType, 1662 ToType, Context, 1663 /*StripObjCLifetime=*/true); 1664 return true; 1665 } 1666 1667 // MSVC allows implicit function to void* type conversion. 1668 if (getLangOptions().MicrosoftExt && FromPointeeType->isFunctionType() && 1669 ToPointeeType->isVoidType()) { 1670 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1671 ToPointeeType, 1672 ToType, Context); 1673 return true; 1674 } 1675 1676 // When we're overloading in C, we allow a special kind of pointer 1677 // conversion for compatible-but-not-identical pointee types. 1678 if (!getLangOptions().CPlusPlus && 1679 Context.typesAreCompatible(FromPointeeType, ToPointeeType)) { 1680 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1681 ToPointeeType, 1682 ToType, Context); 1683 return true; 1684 } 1685 1686 // C++ [conv.ptr]p3: 1687 // 1688 // An rvalue of type "pointer to cv D," where D is a class type, 1689 // can be converted to an rvalue of type "pointer to cv B," where 1690 // B is a base class (clause 10) of D. If B is an inaccessible 1691 // (clause 11) or ambiguous (10.2) base class of D, a program that 1692 // necessitates this conversion is ill-formed. The result of the 1693 // conversion is a pointer to the base class sub-object of the 1694 // derived class object. The null pointer value is converted to 1695 // the null pointer value of the destination type. 1696 // 1697 // Note that we do not check for ambiguity or inaccessibility 1698 // here. That is handled by CheckPointerConversion. 1699 if (getLangOptions().CPlusPlus && 1700 FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 1701 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType) && 1702 !RequireCompleteType(From->getLocStart(), FromPointeeType, PDiag()) && 1703 IsDerivedFrom(FromPointeeType, ToPointeeType)) { 1704 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1705 ToPointeeType, 1706 ToType, Context); 1707 return true; 1708 } 1709 1710 if (FromPointeeType->isVectorType() && ToPointeeType->isVectorType() && 1711 Context.areCompatibleVectorTypes(FromPointeeType, ToPointeeType)) { 1712 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1713 ToPointeeType, 1714 ToType, Context); 1715 return true; 1716 } 1717 1718 return false; 1719} 1720 1721/// \brief Adopt the given qualifiers for the given type. 1722static QualType AdoptQualifiers(ASTContext &Context, QualType T, Qualifiers Qs){ 1723 Qualifiers TQs = T.getQualifiers(); 1724 1725 // Check whether qualifiers already match. 1726 if (TQs == Qs) 1727 return T; 1728 1729 if (Qs.compatiblyIncludes(TQs)) 1730 return Context.getQualifiedType(T, Qs); 1731 1732 return Context.getQualifiedType(T.getUnqualifiedType(), Qs); 1733} 1734 1735/// isObjCPointerConversion - Determines whether this is an 1736/// Objective-C pointer conversion. Subroutine of IsPointerConversion, 1737/// with the same arguments and return values. 1738bool Sema::isObjCPointerConversion(QualType FromType, QualType ToType, 1739 QualType& ConvertedType, 1740 bool &IncompatibleObjC) { 1741 if (!getLangOptions().ObjC1) 1742 return false; 1743 1744 // The set of qualifiers on the type we're converting from. 1745 Qualifiers FromQualifiers = FromType.getQualifiers(); 1746 1747 // First, we handle all conversions on ObjC object pointer types. 1748 const ObjCObjectPointerType* ToObjCPtr = 1749 ToType->getAs<ObjCObjectPointerType>(); 1750 const ObjCObjectPointerType *FromObjCPtr = 1751 FromType->getAs<ObjCObjectPointerType>(); 1752 1753 if (ToObjCPtr && FromObjCPtr) { 1754 // If the pointee types are the same (ignoring qualifications), 1755 // then this is not a pointer conversion. 1756 if (Context.hasSameUnqualifiedType(ToObjCPtr->getPointeeType(), 1757 FromObjCPtr->getPointeeType())) 1758 return false; 1759 1760 // Check for compatible 1761 // Objective C++: We're able to convert between "id" or "Class" and a 1762 // pointer to any interface (in both directions). 1763 if (ToObjCPtr->isObjCBuiltinType() && FromObjCPtr->isObjCBuiltinType()) { 1764 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1765 return true; 1766 } 1767 // Conversions with Objective-C's id<...>. 1768 if ((FromObjCPtr->isObjCQualifiedIdType() || 1769 ToObjCPtr->isObjCQualifiedIdType()) && 1770 Context.ObjCQualifiedIdTypesAreCompatible(ToType, FromType, 1771 /*compare=*/false)) { 1772 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1773 return true; 1774 } 1775 // Objective C++: We're able to convert from a pointer to an 1776 // interface to a pointer to a different interface. 1777 if (Context.canAssignObjCInterfaces(ToObjCPtr, FromObjCPtr)) { 1778 const ObjCInterfaceType* LHS = ToObjCPtr->getInterfaceType(); 1779 const ObjCInterfaceType* RHS = FromObjCPtr->getInterfaceType(); 1780 if (getLangOptions().CPlusPlus && LHS && RHS && 1781 !ToObjCPtr->getPointeeType().isAtLeastAsQualifiedAs( 1782 FromObjCPtr->getPointeeType())) 1783 return false; 1784 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 1785 ToObjCPtr->getPointeeType(), 1786 ToType, Context); 1787 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1788 return true; 1789 } 1790 1791 if (Context.canAssignObjCInterfaces(FromObjCPtr, ToObjCPtr)) { 1792 // Okay: this is some kind of implicit downcast of Objective-C 1793 // interfaces, which is permitted. However, we're going to 1794 // complain about it. 1795 IncompatibleObjC = true; 1796 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 1797 ToObjCPtr->getPointeeType(), 1798 ToType, Context); 1799 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1800 return true; 1801 } 1802 } 1803 // Beyond this point, both types need to be C pointers or block pointers. 1804 QualType ToPointeeType; 1805 if (const PointerType *ToCPtr = ToType->getAs<PointerType>()) 1806 ToPointeeType = ToCPtr->getPointeeType(); 1807 else if (const BlockPointerType *ToBlockPtr = 1808 ToType->getAs<BlockPointerType>()) { 1809 // Objective C++: We're able to convert from a pointer to any object 1810 // to a block pointer type. 1811 if (FromObjCPtr && FromObjCPtr->isObjCBuiltinType()) { 1812 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1813 return true; 1814 } 1815 ToPointeeType = ToBlockPtr->getPointeeType(); 1816 } 1817 else if (FromType->getAs<BlockPointerType>() && 1818 ToObjCPtr && ToObjCPtr->isObjCBuiltinType()) { 1819 // Objective C++: We're able to convert from a block pointer type to a 1820 // pointer to any object. 1821 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1822 return true; 1823 } 1824 else 1825 return false; 1826 1827 QualType FromPointeeType; 1828 if (const PointerType *FromCPtr = FromType->getAs<PointerType>()) 1829 FromPointeeType = FromCPtr->getPointeeType(); 1830 else if (const BlockPointerType *FromBlockPtr = 1831 FromType->getAs<BlockPointerType>()) 1832 FromPointeeType = FromBlockPtr->getPointeeType(); 1833 else 1834 return false; 1835 1836 // If we have pointers to pointers, recursively check whether this 1837 // is an Objective-C conversion. 1838 if (FromPointeeType->isPointerType() && ToPointeeType->isPointerType() && 1839 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1840 IncompatibleObjC)) { 1841 // We always complain about this conversion. 1842 IncompatibleObjC = true; 1843 ConvertedType = Context.getPointerType(ConvertedType); 1844 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1845 return true; 1846 } 1847 // Allow conversion of pointee being objective-c pointer to another one; 1848 // as in I* to id. 1849 if (FromPointeeType->getAs<ObjCObjectPointerType>() && 1850 ToPointeeType->getAs<ObjCObjectPointerType>() && 1851 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1852 IncompatibleObjC)) { 1853 1854 ConvertedType = Context.getPointerType(ConvertedType); 1855 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1856 return true; 1857 } 1858 1859 // If we have pointers to functions or blocks, check whether the only 1860 // differences in the argument and result types are in Objective-C 1861 // pointer conversions. If so, we permit the conversion (but 1862 // complain about it). 1863 const FunctionProtoType *FromFunctionType 1864 = FromPointeeType->getAs<FunctionProtoType>(); 1865 const FunctionProtoType *ToFunctionType 1866 = ToPointeeType->getAs<FunctionProtoType>(); 1867 if (FromFunctionType && ToFunctionType) { 1868 // If the function types are exactly the same, this isn't an 1869 // Objective-C pointer conversion. 1870 if (Context.getCanonicalType(FromPointeeType) 1871 == Context.getCanonicalType(ToPointeeType)) 1872 return false; 1873 1874 // Perform the quick checks that will tell us whether these 1875 // function types are obviously different. 1876 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 1877 FromFunctionType->isVariadic() != ToFunctionType->isVariadic() || 1878 FromFunctionType->getTypeQuals() != ToFunctionType->getTypeQuals()) 1879 return false; 1880 1881 bool HasObjCConversion = false; 1882 if (Context.getCanonicalType(FromFunctionType->getResultType()) 1883 == Context.getCanonicalType(ToFunctionType->getResultType())) { 1884 // Okay, the types match exactly. Nothing to do. 1885 } else if (isObjCPointerConversion(FromFunctionType->getResultType(), 1886 ToFunctionType->getResultType(), 1887 ConvertedType, IncompatibleObjC)) { 1888 // Okay, we have an Objective-C pointer conversion. 1889 HasObjCConversion = true; 1890 } else { 1891 // Function types are too different. Abort. 1892 return false; 1893 } 1894 1895 // Check argument types. 1896 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 1897 ArgIdx != NumArgs; ++ArgIdx) { 1898 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 1899 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 1900 if (Context.getCanonicalType(FromArgType) 1901 == Context.getCanonicalType(ToArgType)) { 1902 // Okay, the types match exactly. Nothing to do. 1903 } else if (isObjCPointerConversion(FromArgType, ToArgType, 1904 ConvertedType, IncompatibleObjC)) { 1905 // Okay, we have an Objective-C pointer conversion. 1906 HasObjCConversion = true; 1907 } else { 1908 // Argument types are too different. Abort. 1909 return false; 1910 } 1911 } 1912 1913 if (HasObjCConversion) { 1914 // We had an Objective-C conversion. Allow this pointer 1915 // conversion, but complain about it. 1916 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1917 IncompatibleObjC = true; 1918 return true; 1919 } 1920 } 1921 1922 return false; 1923} 1924 1925/// \brief Determine whether this is an Objective-C writeback conversion, 1926/// used for parameter passing when performing automatic reference counting. 1927/// 1928/// \param FromType The type we're converting form. 1929/// 1930/// \param ToType The type we're converting to. 1931/// 1932/// \param ConvertedType The type that will be produced after applying 1933/// this conversion. 1934bool Sema::isObjCWritebackConversion(QualType FromType, QualType ToType, 1935 QualType &ConvertedType) { 1936 if (!getLangOptions().ObjCAutoRefCount || 1937 Context.hasSameUnqualifiedType(FromType, ToType)) 1938 return false; 1939 1940 // Parameter must be a pointer to __autoreleasing (with no other qualifiers). 1941 QualType ToPointee; 1942 if (const PointerType *ToPointer = ToType->getAs<PointerType>()) 1943 ToPointee = ToPointer->getPointeeType(); 1944 else 1945 return false; 1946 1947 Qualifiers ToQuals = ToPointee.getQualifiers(); 1948 if (!ToPointee->isObjCLifetimeType() || 1949 ToQuals.getObjCLifetime() != Qualifiers::OCL_Autoreleasing || 1950 !ToQuals.withoutObjCGLifetime().empty()) 1951 return false; 1952 1953 // Argument must be a pointer to __strong to __weak. 1954 QualType FromPointee; 1955 if (const PointerType *FromPointer = FromType->getAs<PointerType>()) 1956 FromPointee = FromPointer->getPointeeType(); 1957 else 1958 return false; 1959 1960 Qualifiers FromQuals = FromPointee.getQualifiers(); 1961 if (!FromPointee->isObjCLifetimeType() || 1962 (FromQuals.getObjCLifetime() != Qualifiers::OCL_Strong && 1963 FromQuals.getObjCLifetime() != Qualifiers::OCL_Weak)) 1964 return false; 1965 1966 // Make sure that we have compatible qualifiers. 1967 FromQuals.setObjCLifetime(Qualifiers::OCL_Autoreleasing); 1968 if (!ToQuals.compatiblyIncludes(FromQuals)) 1969 return false; 1970 1971 // Remove qualifiers from the pointee type we're converting from; they 1972 // aren't used in the compatibility check belong, and we'll be adding back 1973 // qualifiers (with __autoreleasing) if the compatibility check succeeds. 1974 FromPointee = FromPointee.getUnqualifiedType(); 1975 1976 // The unqualified form of the pointee types must be compatible. 1977 ToPointee = ToPointee.getUnqualifiedType(); 1978 bool IncompatibleObjC; 1979 if (Context.typesAreCompatible(FromPointee, ToPointee)) 1980 FromPointee = ToPointee; 1981 else if (!isObjCPointerConversion(FromPointee, ToPointee, FromPointee, 1982 IncompatibleObjC)) 1983 return false; 1984 1985 /// \brief Construct the type we're converting to, which is a pointer to 1986 /// __autoreleasing pointee. 1987 FromPointee = Context.getQualifiedType(FromPointee, FromQuals); 1988 ConvertedType = Context.getPointerType(FromPointee); 1989 return true; 1990} 1991 1992bool Sema::IsBlockPointerConversion(QualType FromType, QualType ToType, 1993 QualType& ConvertedType) { 1994 QualType ToPointeeType; 1995 if (const BlockPointerType *ToBlockPtr = 1996 ToType->getAs<BlockPointerType>()) 1997 ToPointeeType = ToBlockPtr->getPointeeType(); 1998 else 1999 return false; 2000 2001 QualType FromPointeeType; 2002 if (const BlockPointerType *FromBlockPtr = 2003 FromType->getAs<BlockPointerType>()) 2004 FromPointeeType = FromBlockPtr->getPointeeType(); 2005 else 2006 return false; 2007 // We have pointer to blocks, check whether the only 2008 // differences in the argument and result types are in Objective-C 2009 // pointer conversions. If so, we permit the conversion. 2010 2011 const FunctionProtoType *FromFunctionType 2012 = FromPointeeType->getAs<FunctionProtoType>(); 2013 const FunctionProtoType *ToFunctionType 2014 = ToPointeeType->getAs<FunctionProtoType>(); 2015 2016 if (!FromFunctionType || !ToFunctionType) 2017 return false; 2018 2019 if (Context.hasSameType(FromPointeeType, ToPointeeType)) 2020 return true; 2021 2022 // Perform the quick checks that will tell us whether these 2023 // function types are obviously different. 2024 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 2025 FromFunctionType->isVariadic() != ToFunctionType->isVariadic()) 2026 return false; 2027 2028 FunctionType::ExtInfo FromEInfo = FromFunctionType->getExtInfo(); 2029 FunctionType::ExtInfo ToEInfo = ToFunctionType->getExtInfo(); 2030 if (FromEInfo != ToEInfo) 2031 return false; 2032 2033 bool IncompatibleObjC = false; 2034 if (Context.hasSameType(FromFunctionType->getResultType(), 2035 ToFunctionType->getResultType())) { 2036 // Okay, the types match exactly. Nothing to do. 2037 } else { 2038 QualType RHS = FromFunctionType->getResultType(); 2039 QualType LHS = ToFunctionType->getResultType(); 2040 if ((!getLangOptions().CPlusPlus || !RHS->isRecordType()) && 2041 !RHS.hasQualifiers() && LHS.hasQualifiers()) 2042 LHS = LHS.getUnqualifiedType(); 2043 2044 if (Context.hasSameType(RHS,LHS)) { 2045 // OK exact match. 2046 } else if (isObjCPointerConversion(RHS, LHS, 2047 ConvertedType, IncompatibleObjC)) { 2048 if (IncompatibleObjC) 2049 return false; 2050 // Okay, we have an Objective-C pointer conversion. 2051 } 2052 else 2053 return false; 2054 } 2055 2056 // Check argument types. 2057 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 2058 ArgIdx != NumArgs; ++ArgIdx) { 2059 IncompatibleObjC = false; 2060 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 2061 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 2062 if (Context.hasSameType(FromArgType, ToArgType)) { 2063 // Okay, the types match exactly. Nothing to do. 2064 } else if (isObjCPointerConversion(ToArgType, FromArgType, 2065 ConvertedType, IncompatibleObjC)) { 2066 if (IncompatibleObjC) 2067 return false; 2068 // Okay, we have an Objective-C pointer conversion. 2069 } else 2070 // Argument types are too different. Abort. 2071 return false; 2072 } 2073 ConvertedType = ToType; 2074 return true; 2075} 2076 2077/// FunctionArgTypesAreEqual - This routine checks two function proto types 2078/// for equlity of their argument types. Caller has already checked that 2079/// they have same number of arguments. This routine assumes that Objective-C 2080/// pointer types which only differ in their protocol qualifiers are equal. 2081bool Sema::FunctionArgTypesAreEqual(const FunctionProtoType *OldType, 2082 const FunctionProtoType *NewType) { 2083 if (!getLangOptions().ObjC1) 2084 return std::equal(OldType->arg_type_begin(), OldType->arg_type_end(), 2085 NewType->arg_type_begin()); 2086 2087 for (FunctionProtoType::arg_type_iterator O = OldType->arg_type_begin(), 2088 N = NewType->arg_type_begin(), 2089 E = OldType->arg_type_end(); O && (O != E); ++O, ++N) { 2090 QualType ToType = (*O); 2091 QualType FromType = (*N); 2092 if (ToType != FromType) { 2093 if (const PointerType *PTTo = ToType->getAs<PointerType>()) { 2094 if (const PointerType *PTFr = FromType->getAs<PointerType>()) 2095 if ((PTTo->getPointeeType()->isObjCQualifiedIdType() && 2096 PTFr->getPointeeType()->isObjCQualifiedIdType()) || 2097 (PTTo->getPointeeType()->isObjCQualifiedClassType() && 2098 PTFr->getPointeeType()->isObjCQualifiedClassType())) 2099 continue; 2100 } 2101 else if (const ObjCObjectPointerType *PTTo = 2102 ToType->getAs<ObjCObjectPointerType>()) { 2103 if (const ObjCObjectPointerType *PTFr = 2104 FromType->getAs<ObjCObjectPointerType>()) 2105 if (PTTo->getInterfaceDecl() == PTFr->getInterfaceDecl()) 2106 continue; 2107 } 2108 return false; 2109 } 2110 } 2111 return true; 2112} 2113 2114/// CheckPointerConversion - Check the pointer conversion from the 2115/// expression From to the type ToType. This routine checks for 2116/// ambiguous or inaccessible derived-to-base pointer 2117/// conversions for which IsPointerConversion has already returned 2118/// true. It returns true and produces a diagnostic if there was an 2119/// error, or returns false otherwise. 2120bool Sema::CheckPointerConversion(Expr *From, QualType ToType, 2121 CastKind &Kind, 2122 CXXCastPath& BasePath, 2123 bool IgnoreBaseAccess) { 2124 QualType FromType = From->getType(); 2125 bool IsCStyleOrFunctionalCast = IgnoreBaseAccess; 2126 2127 Kind = CK_BitCast; 2128 2129 if (!IsCStyleOrFunctionalCast && 2130 Context.hasSameUnqualifiedType(From->getType(), Context.BoolTy) && 2131 From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 2132 DiagRuntimeBehavior(From->getExprLoc(), From, 2133 PDiag(diag::warn_impcast_bool_to_null_pointer) 2134 << ToType << From->getSourceRange()); 2135 2136 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) { 2137 if (const PointerType *FromPtrType = FromType->getAs<PointerType>()) { 2138 QualType FromPointeeType = FromPtrType->getPointeeType(), 2139 ToPointeeType = ToPtrType->getPointeeType(); 2140 2141 if (FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 2142 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) { 2143 // We must have a derived-to-base conversion. Check an 2144 // ambiguous or inaccessible conversion. 2145 if (CheckDerivedToBaseConversion(FromPointeeType, ToPointeeType, 2146 From->getExprLoc(), 2147 From->getSourceRange(), &BasePath, 2148 IgnoreBaseAccess)) 2149 return true; 2150 2151 // The conversion was successful. 2152 Kind = CK_DerivedToBase; 2153 } 2154 } 2155 } else if (const ObjCObjectPointerType *ToPtrType = 2156 ToType->getAs<ObjCObjectPointerType>()) { 2157 if (const ObjCObjectPointerType *FromPtrType = 2158 FromType->getAs<ObjCObjectPointerType>()) { 2159 // Objective-C++ conversions are always okay. 2160 // FIXME: We should have a different class of conversions for the 2161 // Objective-C++ implicit conversions. 2162 if (FromPtrType->isObjCBuiltinType() || ToPtrType->isObjCBuiltinType()) 2163 return false; 2164 } else if (FromType->isBlockPointerType()) { 2165 Kind = CK_BlockPointerToObjCPointerCast; 2166 } else { 2167 Kind = CK_CPointerToObjCPointerCast; 2168 } 2169 } else if (ToType->isBlockPointerType()) { 2170 if (!FromType->isBlockPointerType()) 2171 Kind = CK_AnyPointerToBlockPointerCast; 2172 } 2173 2174 // We shouldn't fall into this case unless it's valid for other 2175 // reasons. 2176 if (From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 2177 Kind = CK_NullToPointer; 2178 2179 return false; 2180} 2181 2182/// IsMemberPointerConversion - Determines whether the conversion of the 2183/// expression From, which has the (possibly adjusted) type FromType, can be 2184/// converted to the type ToType via a member pointer conversion (C++ 4.11). 2185/// If so, returns true and places the converted type (that might differ from 2186/// ToType in its cv-qualifiers at some level) into ConvertedType. 2187bool Sema::IsMemberPointerConversion(Expr *From, QualType FromType, 2188 QualType ToType, 2189 bool InOverloadResolution, 2190 QualType &ConvertedType) { 2191 const MemberPointerType *ToTypePtr = ToType->getAs<MemberPointerType>(); 2192 if (!ToTypePtr) 2193 return false; 2194 2195 // A null pointer constant can be converted to a member pointer (C++ 4.11p1) 2196 if (From->isNullPointerConstant(Context, 2197 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 2198 : Expr::NPC_ValueDependentIsNull)) { 2199 ConvertedType = ToType; 2200 return true; 2201 } 2202 2203 // Otherwise, both types have to be member pointers. 2204 const MemberPointerType *FromTypePtr = FromType->getAs<MemberPointerType>(); 2205 if (!FromTypePtr) 2206 return false; 2207 2208 // A pointer to member of B can be converted to a pointer to member of D, 2209 // where D is derived from B (C++ 4.11p2). 2210 QualType FromClass(FromTypePtr->getClass(), 0); 2211 QualType ToClass(ToTypePtr->getClass(), 0); 2212 2213 if (!Context.hasSameUnqualifiedType(FromClass, ToClass) && 2214 !RequireCompleteType(From->getLocStart(), ToClass, PDiag()) && 2215 IsDerivedFrom(ToClass, FromClass)) { 2216 ConvertedType = Context.getMemberPointerType(FromTypePtr->getPointeeType(), 2217 ToClass.getTypePtr()); 2218 return true; 2219 } 2220 2221 return false; 2222} 2223 2224/// CheckMemberPointerConversion - Check the member pointer conversion from the 2225/// expression From to the type ToType. This routine checks for ambiguous or 2226/// virtual or inaccessible base-to-derived member pointer conversions 2227/// for which IsMemberPointerConversion has already returned true. It returns 2228/// true and produces a diagnostic if there was an error, or returns false 2229/// otherwise. 2230bool Sema::CheckMemberPointerConversion(Expr *From, QualType ToType, 2231 CastKind &Kind, 2232 CXXCastPath &BasePath, 2233 bool IgnoreBaseAccess) { 2234 QualType FromType = From->getType(); 2235 const MemberPointerType *FromPtrType = FromType->getAs<MemberPointerType>(); 2236 if (!FromPtrType) { 2237 // This must be a null pointer to member pointer conversion 2238 assert(From->isNullPointerConstant(Context, 2239 Expr::NPC_ValueDependentIsNull) && 2240 "Expr must be null pointer constant!"); 2241 Kind = CK_NullToMemberPointer; 2242 return false; 2243 } 2244 2245 const MemberPointerType *ToPtrType = ToType->getAs<MemberPointerType>(); 2246 assert(ToPtrType && "No member pointer cast has a target type " 2247 "that is not a member pointer."); 2248 2249 QualType FromClass = QualType(FromPtrType->getClass(), 0); 2250 QualType ToClass = QualType(ToPtrType->getClass(), 0); 2251 2252 // FIXME: What about dependent types? 2253 assert(FromClass->isRecordType() && "Pointer into non-class."); 2254 assert(ToClass->isRecordType() && "Pointer into non-class."); 2255 2256 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 2257 /*DetectVirtual=*/true); 2258 bool DerivationOkay = IsDerivedFrom(ToClass, FromClass, Paths); 2259 assert(DerivationOkay && 2260 "Should not have been called if derivation isn't OK."); 2261 (void)DerivationOkay; 2262 2263 if (Paths.isAmbiguous(Context.getCanonicalType(FromClass). 2264 getUnqualifiedType())) { 2265 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths); 2266 Diag(From->getExprLoc(), diag::err_ambiguous_memptr_conv) 2267 << 0 << FromClass << ToClass << PathDisplayStr << From->getSourceRange(); 2268 return true; 2269 } 2270 2271 if (const RecordType *VBase = Paths.getDetectedVirtual()) { 2272 Diag(From->getExprLoc(), diag::err_memptr_conv_via_virtual) 2273 << FromClass << ToClass << QualType(VBase, 0) 2274 << From->getSourceRange(); 2275 return true; 2276 } 2277 2278 if (!IgnoreBaseAccess) 2279 CheckBaseClassAccess(From->getExprLoc(), FromClass, ToClass, 2280 Paths.front(), 2281 diag::err_downcast_from_inaccessible_base); 2282 2283 // Must be a base to derived member conversion. 2284 BuildBasePathArray(Paths, BasePath); 2285 Kind = CK_BaseToDerivedMemberPointer; 2286 return false; 2287} 2288 2289/// IsQualificationConversion - Determines whether the conversion from 2290/// an rvalue of type FromType to ToType is a qualification conversion 2291/// (C++ 4.4). 2292/// 2293/// \param ObjCLifetimeConversion Output parameter that will be set to indicate 2294/// when the qualification conversion involves a change in the Objective-C 2295/// object lifetime. 2296bool 2297Sema::IsQualificationConversion(QualType FromType, QualType ToType, 2298 bool CStyle, bool &ObjCLifetimeConversion) { 2299 FromType = Context.getCanonicalType(FromType); 2300 ToType = Context.getCanonicalType(ToType); 2301 ObjCLifetimeConversion = false; 2302 2303 // If FromType and ToType are the same type, this is not a 2304 // qualification conversion. 2305 if (FromType.getUnqualifiedType() == ToType.getUnqualifiedType()) 2306 return false; 2307 2308 // (C++ 4.4p4): 2309 // A conversion can add cv-qualifiers at levels other than the first 2310 // in multi-level pointers, subject to the following rules: [...] 2311 bool PreviousToQualsIncludeConst = true; 2312 bool UnwrappedAnyPointer = false; 2313 while (Context.UnwrapSimilarPointerTypes(FromType, ToType)) { 2314 // Within each iteration of the loop, we check the qualifiers to 2315 // determine if this still looks like a qualification 2316 // conversion. Then, if all is well, we unwrap one more level of 2317 // pointers or pointers-to-members and do it all again 2318 // until there are no more pointers or pointers-to-members left to 2319 // unwrap. 2320 UnwrappedAnyPointer = true; 2321 2322 Qualifiers FromQuals = FromType.getQualifiers(); 2323 Qualifiers ToQuals = ToType.getQualifiers(); 2324 2325 // Objective-C ARC: 2326 // Check Objective-C lifetime conversions. 2327 if (FromQuals.getObjCLifetime() != ToQuals.getObjCLifetime() && 2328 UnwrappedAnyPointer) { 2329 if (ToQuals.compatiblyIncludesObjCLifetime(FromQuals)) { 2330 ObjCLifetimeConversion = true; 2331 FromQuals.removeObjCLifetime(); 2332 ToQuals.removeObjCLifetime(); 2333 } else { 2334 // Qualification conversions cannot cast between different 2335 // Objective-C lifetime qualifiers. 2336 return false; 2337 } 2338 } 2339 2340 // Allow addition/removal of GC attributes but not changing GC attributes. 2341 if (FromQuals.getObjCGCAttr() != ToQuals.getObjCGCAttr() && 2342 (!FromQuals.hasObjCGCAttr() || !ToQuals.hasObjCGCAttr())) { 2343 FromQuals.removeObjCGCAttr(); 2344 ToQuals.removeObjCGCAttr(); 2345 } 2346 2347 // -- for every j > 0, if const is in cv 1,j then const is in cv 2348 // 2,j, and similarly for volatile. 2349 if (!CStyle && !ToQuals.compatiblyIncludes(FromQuals)) 2350 return false; 2351 2352 // -- if the cv 1,j and cv 2,j are different, then const is in 2353 // every cv for 0 < k < j. 2354 if (!CStyle && FromQuals.getCVRQualifiers() != ToQuals.getCVRQualifiers() 2355 && !PreviousToQualsIncludeConst) 2356 return false; 2357 2358 // Keep track of whether all prior cv-qualifiers in the "to" type 2359 // include const. 2360 PreviousToQualsIncludeConst 2361 = PreviousToQualsIncludeConst && ToQuals.hasConst(); 2362 } 2363 2364 // We are left with FromType and ToType being the pointee types 2365 // after unwrapping the original FromType and ToType the same number 2366 // of types. If we unwrapped any pointers, and if FromType and 2367 // ToType have the same unqualified type (since we checked 2368 // qualifiers above), then this is a qualification conversion. 2369 return UnwrappedAnyPointer && Context.hasSameUnqualifiedType(FromType,ToType); 2370} 2371 2372/// Determines whether there is a user-defined conversion sequence 2373/// (C++ [over.ics.user]) that converts expression From to the type 2374/// ToType. If such a conversion exists, User will contain the 2375/// user-defined conversion sequence that performs such a conversion 2376/// and this routine will return true. Otherwise, this routine returns 2377/// false and User is unspecified. 2378/// 2379/// \param AllowExplicit true if the conversion should consider C++0x 2380/// "explicit" conversion functions as well as non-explicit conversion 2381/// functions (C++0x [class.conv.fct]p2). 2382static OverloadingResult 2383IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 2384 UserDefinedConversionSequence& User, 2385 OverloadCandidateSet& CandidateSet, 2386 bool AllowExplicit) { 2387 // Whether we will only visit constructors. 2388 bool ConstructorsOnly = false; 2389 2390 // If the type we are conversion to is a class type, enumerate its 2391 // constructors. 2392 if (const RecordType *ToRecordType = ToType->getAs<RecordType>()) { 2393 // C++ [over.match.ctor]p1: 2394 // When objects of class type are direct-initialized (8.5), or 2395 // copy-initialized from an expression of the same or a 2396 // derived class type (8.5), overload resolution selects the 2397 // constructor. [...] For copy-initialization, the candidate 2398 // functions are all the converting constructors (12.3.1) of 2399 // that class. The argument list is the expression-list within 2400 // the parentheses of the initializer. 2401 if (S.Context.hasSameUnqualifiedType(ToType, From->getType()) || 2402 (From->getType()->getAs<RecordType>() && 2403 S.IsDerivedFrom(From->getType(), ToType))) 2404 ConstructorsOnly = true; 2405 2406 S.RequireCompleteType(From->getLocStart(), ToType, S.PDiag()); 2407 // RequireCompleteType may have returned true due to some invalid decl 2408 // during template instantiation, but ToType may be complete enough now 2409 // to try to recover. 2410 if (ToType->isIncompleteType()) { 2411 // We're not going to find any constructors. 2412 } else if (CXXRecordDecl *ToRecordDecl 2413 = dyn_cast<CXXRecordDecl>(ToRecordType->getDecl())) { 2414 DeclContext::lookup_iterator Con, ConEnd; 2415 for (llvm::tie(Con, ConEnd) = S.LookupConstructors(ToRecordDecl); 2416 Con != ConEnd; ++Con) { 2417 NamedDecl *D = *Con; 2418 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2419 2420 // Find the constructor (which may be a template). 2421 CXXConstructorDecl *Constructor = 0; 2422 FunctionTemplateDecl *ConstructorTmpl 2423 = dyn_cast<FunctionTemplateDecl>(D); 2424 if (ConstructorTmpl) 2425 Constructor 2426 = cast<CXXConstructorDecl>(ConstructorTmpl->getTemplatedDecl()); 2427 else 2428 Constructor = cast<CXXConstructorDecl>(D); 2429 2430 if (!Constructor->isInvalidDecl() && 2431 Constructor->isConvertingConstructor(AllowExplicit)) { 2432 if (ConstructorTmpl) 2433 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2434 /*ExplicitArgs*/ 0, 2435 &From, 1, CandidateSet, 2436 /*SuppressUserConversions=*/ 2437 !ConstructorsOnly); 2438 else 2439 // Allow one user-defined conversion when user specifies a 2440 // From->ToType conversion via an static cast (c-style, etc). 2441 S.AddOverloadCandidate(Constructor, FoundDecl, 2442 &From, 1, CandidateSet, 2443 /*SuppressUserConversions=*/ 2444 !ConstructorsOnly); 2445 } 2446 } 2447 } 2448 } 2449 2450 // Enumerate conversion functions, if we're allowed to. 2451 if (ConstructorsOnly) { 2452 } else if (S.RequireCompleteType(From->getLocStart(), From->getType(), 2453 S.PDiag(0) << From->getSourceRange())) { 2454 // No conversion functions from incomplete types. 2455 } else if (const RecordType *FromRecordType 2456 = From->getType()->getAs<RecordType>()) { 2457 if (CXXRecordDecl *FromRecordDecl 2458 = dyn_cast<CXXRecordDecl>(FromRecordType->getDecl())) { 2459 // Add all of the conversion functions as candidates. 2460 const UnresolvedSetImpl *Conversions 2461 = FromRecordDecl->getVisibleConversionFunctions(); 2462 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 2463 E = Conversions->end(); I != E; ++I) { 2464 DeclAccessPair FoundDecl = I.getPair(); 2465 NamedDecl *D = FoundDecl.getDecl(); 2466 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 2467 if (isa<UsingShadowDecl>(D)) 2468 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2469 2470 CXXConversionDecl *Conv; 2471 FunctionTemplateDecl *ConvTemplate; 2472 if ((ConvTemplate = dyn_cast<FunctionTemplateDecl>(D))) 2473 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 2474 else 2475 Conv = cast<CXXConversionDecl>(D); 2476 2477 if (AllowExplicit || !Conv->isExplicit()) { 2478 if (ConvTemplate) 2479 S.AddTemplateConversionCandidate(ConvTemplate, FoundDecl, 2480 ActingContext, From, ToType, 2481 CandidateSet); 2482 else 2483 S.AddConversionCandidate(Conv, FoundDecl, ActingContext, 2484 From, ToType, CandidateSet); 2485 } 2486 } 2487 } 2488 } 2489 2490 OverloadCandidateSet::iterator Best; 2491 switch (CandidateSet.BestViableFunction(S, From->getLocStart(), Best, true)) { 2492 case OR_Success: 2493 // Record the standard conversion we used and the conversion function. 2494 if (CXXConstructorDecl *Constructor 2495 = dyn_cast<CXXConstructorDecl>(Best->Function)) { 2496 S.MarkDeclarationReferenced(From->getLocStart(), Constructor); 2497 2498 // C++ [over.ics.user]p1: 2499 // If the user-defined conversion is specified by a 2500 // constructor (12.3.1), the initial standard conversion 2501 // sequence converts the source type to the type required by 2502 // the argument of the constructor. 2503 // 2504 QualType ThisType = Constructor->getThisType(S.Context); 2505 if (Best->Conversions[0].isEllipsis()) 2506 User.EllipsisConversion = true; 2507 else { 2508 User.Before = Best->Conversions[0].Standard; 2509 User.EllipsisConversion = false; 2510 } 2511 User.ConversionFunction = Constructor; 2512 User.FoundConversionFunction = Best->FoundDecl; 2513 User.After.setAsIdentityConversion(); 2514 User.After.setFromType(ThisType->getAs<PointerType>()->getPointeeType()); 2515 User.After.setAllToTypes(ToType); 2516 return OR_Success; 2517 } else if (CXXConversionDecl *Conversion 2518 = dyn_cast<CXXConversionDecl>(Best->Function)) { 2519 S.MarkDeclarationReferenced(From->getLocStart(), Conversion); 2520 2521 // C++ [over.ics.user]p1: 2522 // 2523 // [...] If the user-defined conversion is specified by a 2524 // conversion function (12.3.2), the initial standard 2525 // conversion sequence converts the source type to the 2526 // implicit object parameter of the conversion function. 2527 User.Before = Best->Conversions[0].Standard; 2528 User.ConversionFunction = Conversion; 2529 User.FoundConversionFunction = Best->FoundDecl; 2530 User.EllipsisConversion = false; 2531 2532 // C++ [over.ics.user]p2: 2533 // The second standard conversion sequence converts the 2534 // result of the user-defined conversion to the target type 2535 // for the sequence. Since an implicit conversion sequence 2536 // is an initialization, the special rules for 2537 // initialization by user-defined conversion apply when 2538 // selecting the best user-defined conversion for a 2539 // user-defined conversion sequence (see 13.3.3 and 2540 // 13.3.3.1). 2541 User.After = Best->FinalConversion; 2542 return OR_Success; 2543 } else { 2544 llvm_unreachable("Not a constructor or conversion function?"); 2545 return OR_No_Viable_Function; 2546 } 2547 2548 case OR_No_Viable_Function: 2549 return OR_No_Viable_Function; 2550 case OR_Deleted: 2551 // No conversion here! We're done. 2552 return OR_Deleted; 2553 2554 case OR_Ambiguous: 2555 return OR_Ambiguous; 2556 } 2557 2558 return OR_No_Viable_Function; 2559} 2560 2561bool 2562Sema::DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType) { 2563 ImplicitConversionSequence ICS; 2564 OverloadCandidateSet CandidateSet(From->getExprLoc()); 2565 OverloadingResult OvResult = 2566 IsUserDefinedConversion(*this, From, ToType, ICS.UserDefined, 2567 CandidateSet, false); 2568 if (OvResult == OR_Ambiguous) 2569 Diag(From->getSourceRange().getBegin(), 2570 diag::err_typecheck_ambiguous_condition) 2571 << From->getType() << ToType << From->getSourceRange(); 2572 else if (OvResult == OR_No_Viable_Function && !CandidateSet.empty()) 2573 Diag(From->getSourceRange().getBegin(), 2574 diag::err_typecheck_nonviable_condition) 2575 << From->getType() << ToType << From->getSourceRange(); 2576 else 2577 return false; 2578 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &From, 1); 2579 return true; 2580} 2581 2582/// CompareImplicitConversionSequences - Compare two implicit 2583/// conversion sequences to determine whether one is better than the 2584/// other or if they are indistinguishable (C++ 13.3.3.2). 2585static ImplicitConversionSequence::CompareKind 2586CompareImplicitConversionSequences(Sema &S, 2587 const ImplicitConversionSequence& ICS1, 2588 const ImplicitConversionSequence& ICS2) 2589{ 2590 // (C++ 13.3.3.2p2): When comparing the basic forms of implicit 2591 // conversion sequences (as defined in 13.3.3.1) 2592 // -- a standard conversion sequence (13.3.3.1.1) is a better 2593 // conversion sequence than a user-defined conversion sequence or 2594 // an ellipsis conversion sequence, and 2595 // -- a user-defined conversion sequence (13.3.3.1.2) is a better 2596 // conversion sequence than an ellipsis conversion sequence 2597 // (13.3.3.1.3). 2598 // 2599 // C++0x [over.best.ics]p10: 2600 // For the purpose of ranking implicit conversion sequences as 2601 // described in 13.3.3.2, the ambiguous conversion sequence is 2602 // treated as a user-defined sequence that is indistinguishable 2603 // from any other user-defined conversion sequence. 2604 if (ICS1.getKindRank() < ICS2.getKindRank()) 2605 return ImplicitConversionSequence::Better; 2606 else if (ICS2.getKindRank() < ICS1.getKindRank()) 2607 return ImplicitConversionSequence::Worse; 2608 2609 // The following checks require both conversion sequences to be of 2610 // the same kind. 2611 if (ICS1.getKind() != ICS2.getKind()) 2612 return ImplicitConversionSequence::Indistinguishable; 2613 2614 // Two implicit conversion sequences of the same form are 2615 // indistinguishable conversion sequences unless one of the 2616 // following rules apply: (C++ 13.3.3.2p3): 2617 if (ICS1.isStandard()) 2618 return CompareStandardConversionSequences(S, ICS1.Standard, ICS2.Standard); 2619 else if (ICS1.isUserDefined()) { 2620 // User-defined conversion sequence U1 is a better conversion 2621 // sequence than another user-defined conversion sequence U2 if 2622 // they contain the same user-defined conversion function or 2623 // constructor and if the second standard conversion sequence of 2624 // U1 is better than the second standard conversion sequence of 2625 // U2 (C++ 13.3.3.2p3). 2626 if (ICS1.UserDefined.ConversionFunction == 2627 ICS2.UserDefined.ConversionFunction) 2628 return CompareStandardConversionSequences(S, 2629 ICS1.UserDefined.After, 2630 ICS2.UserDefined.After); 2631 } 2632 2633 return ImplicitConversionSequence::Indistinguishable; 2634} 2635 2636static bool hasSimilarType(ASTContext &Context, QualType T1, QualType T2) { 2637 while (Context.UnwrapSimilarPointerTypes(T1, T2)) { 2638 Qualifiers Quals; 2639 T1 = Context.getUnqualifiedArrayType(T1, Quals); 2640 T2 = Context.getUnqualifiedArrayType(T2, Quals); 2641 } 2642 2643 return Context.hasSameUnqualifiedType(T1, T2); 2644} 2645 2646// Per 13.3.3.2p3, compare the given standard conversion sequences to 2647// determine if one is a proper subset of the other. 2648static ImplicitConversionSequence::CompareKind 2649compareStandardConversionSubsets(ASTContext &Context, 2650 const StandardConversionSequence& SCS1, 2651 const StandardConversionSequence& SCS2) { 2652 ImplicitConversionSequence::CompareKind Result 2653 = ImplicitConversionSequence::Indistinguishable; 2654 2655 // the identity conversion sequence is considered to be a subsequence of 2656 // any non-identity conversion sequence 2657 if (SCS1.isIdentityConversion() && !SCS2.isIdentityConversion()) 2658 return ImplicitConversionSequence::Better; 2659 else if (!SCS1.isIdentityConversion() && SCS2.isIdentityConversion()) 2660 return ImplicitConversionSequence::Worse; 2661 2662 if (SCS1.Second != SCS2.Second) { 2663 if (SCS1.Second == ICK_Identity) 2664 Result = ImplicitConversionSequence::Better; 2665 else if (SCS2.Second == ICK_Identity) 2666 Result = ImplicitConversionSequence::Worse; 2667 else 2668 return ImplicitConversionSequence::Indistinguishable; 2669 } else if (!hasSimilarType(Context, SCS1.getToType(1), SCS2.getToType(1))) 2670 return ImplicitConversionSequence::Indistinguishable; 2671 2672 if (SCS1.Third == SCS2.Third) { 2673 return Context.hasSameType(SCS1.getToType(2), SCS2.getToType(2))? Result 2674 : ImplicitConversionSequence::Indistinguishable; 2675 } 2676 2677 if (SCS1.Third == ICK_Identity) 2678 return Result == ImplicitConversionSequence::Worse 2679 ? ImplicitConversionSequence::Indistinguishable 2680 : ImplicitConversionSequence::Better; 2681 2682 if (SCS2.Third == ICK_Identity) 2683 return Result == ImplicitConversionSequence::Better 2684 ? ImplicitConversionSequence::Indistinguishable 2685 : ImplicitConversionSequence::Worse; 2686 2687 return ImplicitConversionSequence::Indistinguishable; 2688} 2689 2690/// \brief Determine whether one of the given reference bindings is better 2691/// than the other based on what kind of bindings they are. 2692static bool isBetterReferenceBindingKind(const StandardConversionSequence &SCS1, 2693 const StandardConversionSequence &SCS2) { 2694 // C++0x [over.ics.rank]p3b4: 2695 // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an 2696 // implicit object parameter of a non-static member function declared 2697 // without a ref-qualifier, and *either* S1 binds an rvalue reference 2698 // to an rvalue and S2 binds an lvalue reference *or S1 binds an 2699 // lvalue reference to a function lvalue and S2 binds an rvalue 2700 // reference*. 2701 // 2702 // FIXME: Rvalue references. We're going rogue with the above edits, 2703 // because the semantics in the current C++0x working paper (N3225 at the 2704 // time of this writing) break the standard definition of std::forward 2705 // and std::reference_wrapper when dealing with references to functions. 2706 // Proposed wording changes submitted to CWG for consideration. 2707 if (SCS1.BindsImplicitObjectArgumentWithoutRefQualifier || 2708 SCS2.BindsImplicitObjectArgumentWithoutRefQualifier) 2709 return false; 2710 2711 return (!SCS1.IsLvalueReference && SCS1.BindsToRvalue && 2712 SCS2.IsLvalueReference) || 2713 (SCS1.IsLvalueReference && SCS1.BindsToFunctionLvalue && 2714 !SCS2.IsLvalueReference); 2715} 2716 2717/// CompareStandardConversionSequences - Compare two standard 2718/// conversion sequences to determine whether one is better than the 2719/// other or if they are indistinguishable (C++ 13.3.3.2p3). 2720static ImplicitConversionSequence::CompareKind 2721CompareStandardConversionSequences(Sema &S, 2722 const StandardConversionSequence& SCS1, 2723 const StandardConversionSequence& SCS2) 2724{ 2725 // Standard conversion sequence S1 is a better conversion sequence 2726 // than standard conversion sequence S2 if (C++ 13.3.3.2p3): 2727 2728 // -- S1 is a proper subsequence of S2 (comparing the conversion 2729 // sequences in the canonical form defined by 13.3.3.1.1, 2730 // excluding any Lvalue Transformation; the identity conversion 2731 // sequence is considered to be a subsequence of any 2732 // non-identity conversion sequence) or, if not that, 2733 if (ImplicitConversionSequence::CompareKind CK 2734 = compareStandardConversionSubsets(S.Context, SCS1, SCS2)) 2735 return CK; 2736 2737 // -- the rank of S1 is better than the rank of S2 (by the rules 2738 // defined below), or, if not that, 2739 ImplicitConversionRank Rank1 = SCS1.getRank(); 2740 ImplicitConversionRank Rank2 = SCS2.getRank(); 2741 if (Rank1 < Rank2) 2742 return ImplicitConversionSequence::Better; 2743 else if (Rank2 < Rank1) 2744 return ImplicitConversionSequence::Worse; 2745 2746 // (C++ 13.3.3.2p4): Two conversion sequences with the same rank 2747 // are indistinguishable unless one of the following rules 2748 // applies: 2749 2750 // A conversion that is not a conversion of a pointer, or 2751 // pointer to member, to bool is better than another conversion 2752 // that is such a conversion. 2753 if (SCS1.isPointerConversionToBool() != SCS2.isPointerConversionToBool()) 2754 return SCS2.isPointerConversionToBool() 2755 ? ImplicitConversionSequence::Better 2756 : ImplicitConversionSequence::Worse; 2757 2758 // C++ [over.ics.rank]p4b2: 2759 // 2760 // If class B is derived directly or indirectly from class A, 2761 // conversion of B* to A* is better than conversion of B* to 2762 // void*, and conversion of A* to void* is better than conversion 2763 // of B* to void*. 2764 bool SCS1ConvertsToVoid 2765 = SCS1.isPointerConversionToVoidPointer(S.Context); 2766 bool SCS2ConvertsToVoid 2767 = SCS2.isPointerConversionToVoidPointer(S.Context); 2768 if (SCS1ConvertsToVoid != SCS2ConvertsToVoid) { 2769 // Exactly one of the conversion sequences is a conversion to 2770 // a void pointer; it's the worse conversion. 2771 return SCS2ConvertsToVoid ? ImplicitConversionSequence::Better 2772 : ImplicitConversionSequence::Worse; 2773 } else if (!SCS1ConvertsToVoid && !SCS2ConvertsToVoid) { 2774 // Neither conversion sequence converts to a void pointer; compare 2775 // their derived-to-base conversions. 2776 if (ImplicitConversionSequence::CompareKind DerivedCK 2777 = CompareDerivedToBaseConversions(S, SCS1, SCS2)) 2778 return DerivedCK; 2779 } else if (SCS1ConvertsToVoid && SCS2ConvertsToVoid && 2780 !S.Context.hasSameType(SCS1.getFromType(), SCS2.getFromType())) { 2781 // Both conversion sequences are conversions to void 2782 // pointers. Compare the source types to determine if there's an 2783 // inheritance relationship in their sources. 2784 QualType FromType1 = SCS1.getFromType(); 2785 QualType FromType2 = SCS2.getFromType(); 2786 2787 // Adjust the types we're converting from via the array-to-pointer 2788 // conversion, if we need to. 2789 if (SCS1.First == ICK_Array_To_Pointer) 2790 FromType1 = S.Context.getArrayDecayedType(FromType1); 2791 if (SCS2.First == ICK_Array_To_Pointer) 2792 FromType2 = S.Context.getArrayDecayedType(FromType2); 2793 2794 QualType FromPointee1 = FromType1->getPointeeType().getUnqualifiedType(); 2795 QualType FromPointee2 = FromType2->getPointeeType().getUnqualifiedType(); 2796 2797 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 2798 return ImplicitConversionSequence::Better; 2799 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 2800 return ImplicitConversionSequence::Worse; 2801 2802 // Objective-C++: If one interface is more specific than the 2803 // other, it is the better one. 2804 const ObjCObjectPointerType* FromObjCPtr1 2805 = FromType1->getAs<ObjCObjectPointerType>(); 2806 const ObjCObjectPointerType* FromObjCPtr2 2807 = FromType2->getAs<ObjCObjectPointerType>(); 2808 if (FromObjCPtr1 && FromObjCPtr2) { 2809 bool AssignLeft = S.Context.canAssignObjCInterfaces(FromObjCPtr1, 2810 FromObjCPtr2); 2811 bool AssignRight = S.Context.canAssignObjCInterfaces(FromObjCPtr2, 2812 FromObjCPtr1); 2813 if (AssignLeft != AssignRight) { 2814 return AssignLeft? ImplicitConversionSequence::Better 2815 : ImplicitConversionSequence::Worse; 2816 } 2817 } 2818 } 2819 2820 // Compare based on qualification conversions (C++ 13.3.3.2p3, 2821 // bullet 3). 2822 if (ImplicitConversionSequence::CompareKind QualCK 2823 = CompareQualificationConversions(S, SCS1, SCS2)) 2824 return QualCK; 2825 2826 if (SCS1.ReferenceBinding && SCS2.ReferenceBinding) { 2827 // Check for a better reference binding based on the kind of bindings. 2828 if (isBetterReferenceBindingKind(SCS1, SCS2)) 2829 return ImplicitConversionSequence::Better; 2830 else if (isBetterReferenceBindingKind(SCS2, SCS1)) 2831 return ImplicitConversionSequence::Worse; 2832 2833 // C++ [over.ics.rank]p3b4: 2834 // -- S1 and S2 are reference bindings (8.5.3), and the types to 2835 // which the references refer are the same type except for 2836 // top-level cv-qualifiers, and the type to which the reference 2837 // initialized by S2 refers is more cv-qualified than the type 2838 // to which the reference initialized by S1 refers. 2839 QualType T1 = SCS1.getToType(2); 2840 QualType T2 = SCS2.getToType(2); 2841 T1 = S.Context.getCanonicalType(T1); 2842 T2 = S.Context.getCanonicalType(T2); 2843 Qualifiers T1Quals, T2Quals; 2844 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 2845 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 2846 if (UnqualT1 == UnqualT2) { 2847 // Objective-C++ ARC: If the references refer to objects with different 2848 // lifetimes, prefer bindings that don't change lifetime. 2849 if (SCS1.ObjCLifetimeConversionBinding != 2850 SCS2.ObjCLifetimeConversionBinding) { 2851 return SCS1.ObjCLifetimeConversionBinding 2852 ? ImplicitConversionSequence::Worse 2853 : ImplicitConversionSequence::Better; 2854 } 2855 2856 // If the type is an array type, promote the element qualifiers to the 2857 // type for comparison. 2858 if (isa<ArrayType>(T1) && T1Quals) 2859 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 2860 if (isa<ArrayType>(T2) && T2Quals) 2861 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 2862 if (T2.isMoreQualifiedThan(T1)) 2863 return ImplicitConversionSequence::Better; 2864 else if (T1.isMoreQualifiedThan(T2)) 2865 return ImplicitConversionSequence::Worse; 2866 } 2867 } 2868 2869 // In Microsoft mode, prefer an integral conversion to a 2870 // floating-to-integral conversion if the integral conversion 2871 // is between types of the same size. 2872 // For example: 2873 // void f(float); 2874 // void f(int); 2875 // int main { 2876 // long a; 2877 // f(a); 2878 // } 2879 // Here, MSVC will call f(int) instead of generating a compile error 2880 // as clang will do in standard mode. 2881 if (S.getLangOptions().MicrosoftMode && 2882 SCS1.Second == ICK_Integral_Conversion && 2883 SCS2.Second == ICK_Floating_Integral && 2884 S.Context.getTypeSize(SCS1.getFromType()) == 2885 S.Context.getTypeSize(SCS1.getToType(2))) 2886 return ImplicitConversionSequence::Better; 2887 2888 return ImplicitConversionSequence::Indistinguishable; 2889} 2890 2891/// CompareQualificationConversions - Compares two standard conversion 2892/// sequences to determine whether they can be ranked based on their 2893/// qualification conversions (C++ 13.3.3.2p3 bullet 3). 2894ImplicitConversionSequence::CompareKind 2895CompareQualificationConversions(Sema &S, 2896 const StandardConversionSequence& SCS1, 2897 const StandardConversionSequence& SCS2) { 2898 // C++ 13.3.3.2p3: 2899 // -- S1 and S2 differ only in their qualification conversion and 2900 // yield similar types T1 and T2 (C++ 4.4), respectively, and the 2901 // cv-qualification signature of type T1 is a proper subset of 2902 // the cv-qualification signature of type T2, and S1 is not the 2903 // deprecated string literal array-to-pointer conversion (4.2). 2904 if (SCS1.First != SCS2.First || SCS1.Second != SCS2.Second || 2905 SCS1.Third != SCS2.Third || SCS1.Third != ICK_Qualification) 2906 return ImplicitConversionSequence::Indistinguishable; 2907 2908 // FIXME: the example in the standard doesn't use a qualification 2909 // conversion (!) 2910 QualType T1 = SCS1.getToType(2); 2911 QualType T2 = SCS2.getToType(2); 2912 T1 = S.Context.getCanonicalType(T1); 2913 T2 = S.Context.getCanonicalType(T2); 2914 Qualifiers T1Quals, T2Quals; 2915 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 2916 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 2917 2918 // If the types are the same, we won't learn anything by unwrapped 2919 // them. 2920 if (UnqualT1 == UnqualT2) 2921 return ImplicitConversionSequence::Indistinguishable; 2922 2923 // If the type is an array type, promote the element qualifiers to the type 2924 // for comparison. 2925 if (isa<ArrayType>(T1) && T1Quals) 2926 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 2927 if (isa<ArrayType>(T2) && T2Quals) 2928 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 2929 2930 ImplicitConversionSequence::CompareKind Result 2931 = ImplicitConversionSequence::Indistinguishable; 2932 2933 // Objective-C++ ARC: 2934 // Prefer qualification conversions not involving a change in lifetime 2935 // to qualification conversions that do not change lifetime. 2936 if (SCS1.QualificationIncludesObjCLifetime != 2937 SCS2.QualificationIncludesObjCLifetime) { 2938 Result = SCS1.QualificationIncludesObjCLifetime 2939 ? ImplicitConversionSequence::Worse 2940 : ImplicitConversionSequence::Better; 2941 } 2942 2943 while (S.Context.UnwrapSimilarPointerTypes(T1, T2)) { 2944 // Within each iteration of the loop, we check the qualifiers to 2945 // determine if this still looks like a qualification 2946 // conversion. Then, if all is well, we unwrap one more level of 2947 // pointers or pointers-to-members and do it all again 2948 // until there are no more pointers or pointers-to-members left 2949 // to unwrap. This essentially mimics what 2950 // IsQualificationConversion does, but here we're checking for a 2951 // strict subset of qualifiers. 2952 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 2953 // The qualifiers are the same, so this doesn't tell us anything 2954 // about how the sequences rank. 2955 ; 2956 else if (T2.isMoreQualifiedThan(T1)) { 2957 // T1 has fewer qualifiers, so it could be the better sequence. 2958 if (Result == ImplicitConversionSequence::Worse) 2959 // Neither has qualifiers that are a subset of the other's 2960 // qualifiers. 2961 return ImplicitConversionSequence::Indistinguishable; 2962 2963 Result = ImplicitConversionSequence::Better; 2964 } else if (T1.isMoreQualifiedThan(T2)) { 2965 // T2 has fewer qualifiers, so it could be the better sequence. 2966 if (Result == ImplicitConversionSequence::Better) 2967 // Neither has qualifiers that are a subset of the other's 2968 // qualifiers. 2969 return ImplicitConversionSequence::Indistinguishable; 2970 2971 Result = ImplicitConversionSequence::Worse; 2972 } else { 2973 // Qualifiers are disjoint. 2974 return ImplicitConversionSequence::Indistinguishable; 2975 } 2976 2977 // If the types after this point are equivalent, we're done. 2978 if (S.Context.hasSameUnqualifiedType(T1, T2)) 2979 break; 2980 } 2981 2982 // Check that the winning standard conversion sequence isn't using 2983 // the deprecated string literal array to pointer conversion. 2984 switch (Result) { 2985 case ImplicitConversionSequence::Better: 2986 if (SCS1.DeprecatedStringLiteralToCharPtr) 2987 Result = ImplicitConversionSequence::Indistinguishable; 2988 break; 2989 2990 case ImplicitConversionSequence::Indistinguishable: 2991 break; 2992 2993 case ImplicitConversionSequence::Worse: 2994 if (SCS2.DeprecatedStringLiteralToCharPtr) 2995 Result = ImplicitConversionSequence::Indistinguishable; 2996 break; 2997 } 2998 2999 return Result; 3000} 3001 3002/// CompareDerivedToBaseConversions - Compares two standard conversion 3003/// sequences to determine whether they can be ranked based on their 3004/// various kinds of derived-to-base conversions (C++ 3005/// [over.ics.rank]p4b3). As part of these checks, we also look at 3006/// conversions between Objective-C interface types. 3007ImplicitConversionSequence::CompareKind 3008CompareDerivedToBaseConversions(Sema &S, 3009 const StandardConversionSequence& SCS1, 3010 const StandardConversionSequence& SCS2) { 3011 QualType FromType1 = SCS1.getFromType(); 3012 QualType ToType1 = SCS1.getToType(1); 3013 QualType FromType2 = SCS2.getFromType(); 3014 QualType ToType2 = SCS2.getToType(1); 3015 3016 // Adjust the types we're converting from via the array-to-pointer 3017 // conversion, if we need to. 3018 if (SCS1.First == ICK_Array_To_Pointer) 3019 FromType1 = S.Context.getArrayDecayedType(FromType1); 3020 if (SCS2.First == ICK_Array_To_Pointer) 3021 FromType2 = S.Context.getArrayDecayedType(FromType2); 3022 3023 // Canonicalize all of the types. 3024 FromType1 = S.Context.getCanonicalType(FromType1); 3025 ToType1 = S.Context.getCanonicalType(ToType1); 3026 FromType2 = S.Context.getCanonicalType(FromType2); 3027 ToType2 = S.Context.getCanonicalType(ToType2); 3028 3029 // C++ [over.ics.rank]p4b3: 3030 // 3031 // If class B is derived directly or indirectly from class A and 3032 // class C is derived directly or indirectly from B, 3033 // 3034 // Compare based on pointer conversions. 3035 if (SCS1.Second == ICK_Pointer_Conversion && 3036 SCS2.Second == ICK_Pointer_Conversion && 3037 /*FIXME: Remove if Objective-C id conversions get their own rank*/ 3038 FromType1->isPointerType() && FromType2->isPointerType() && 3039 ToType1->isPointerType() && ToType2->isPointerType()) { 3040 QualType FromPointee1 3041 = FromType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3042 QualType ToPointee1 3043 = ToType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3044 QualType FromPointee2 3045 = FromType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3046 QualType ToPointee2 3047 = ToType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 3048 3049 // -- conversion of C* to B* is better than conversion of C* to A*, 3050 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 3051 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 3052 return ImplicitConversionSequence::Better; 3053 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 3054 return ImplicitConversionSequence::Worse; 3055 } 3056 3057 // -- conversion of B* to A* is better than conversion of C* to A*, 3058 if (FromPointee1 != FromPointee2 && ToPointee1 == ToPointee2) { 3059 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 3060 return ImplicitConversionSequence::Better; 3061 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 3062 return ImplicitConversionSequence::Worse; 3063 } 3064 } else if (SCS1.Second == ICK_Pointer_Conversion && 3065 SCS2.Second == ICK_Pointer_Conversion) { 3066 const ObjCObjectPointerType *FromPtr1 3067 = FromType1->getAs<ObjCObjectPointerType>(); 3068 const ObjCObjectPointerType *FromPtr2 3069 = FromType2->getAs<ObjCObjectPointerType>(); 3070 const ObjCObjectPointerType *ToPtr1 3071 = ToType1->getAs<ObjCObjectPointerType>(); 3072 const ObjCObjectPointerType *ToPtr2 3073 = ToType2->getAs<ObjCObjectPointerType>(); 3074 3075 if (FromPtr1 && FromPtr2 && ToPtr1 && ToPtr2) { 3076 // Apply the same conversion ranking rules for Objective-C pointer types 3077 // that we do for C++ pointers to class types. However, we employ the 3078 // Objective-C pseudo-subtyping relationship used for assignment of 3079 // Objective-C pointer types. 3080 bool FromAssignLeft 3081 = S.Context.canAssignObjCInterfaces(FromPtr1, FromPtr2); 3082 bool FromAssignRight 3083 = S.Context.canAssignObjCInterfaces(FromPtr2, FromPtr1); 3084 bool ToAssignLeft 3085 = S.Context.canAssignObjCInterfaces(ToPtr1, ToPtr2); 3086 bool ToAssignRight 3087 = S.Context.canAssignObjCInterfaces(ToPtr2, ToPtr1); 3088 3089 // A conversion to an a non-id object pointer type or qualified 'id' 3090 // type is better than a conversion to 'id'. 3091 if (ToPtr1->isObjCIdType() && 3092 (ToPtr2->isObjCQualifiedIdType() || ToPtr2->getInterfaceDecl())) 3093 return ImplicitConversionSequence::Worse; 3094 if (ToPtr2->isObjCIdType() && 3095 (ToPtr1->isObjCQualifiedIdType() || ToPtr1->getInterfaceDecl())) 3096 return ImplicitConversionSequence::Better; 3097 3098 // A conversion to a non-id object pointer type is better than a 3099 // conversion to a qualified 'id' type 3100 if (ToPtr1->isObjCQualifiedIdType() && ToPtr2->getInterfaceDecl()) 3101 return ImplicitConversionSequence::Worse; 3102 if (ToPtr2->isObjCQualifiedIdType() && ToPtr1->getInterfaceDecl()) 3103 return ImplicitConversionSequence::Better; 3104 3105 // A conversion to an a non-Class object pointer type or qualified 'Class' 3106 // type is better than a conversion to 'Class'. 3107 if (ToPtr1->isObjCClassType() && 3108 (ToPtr2->isObjCQualifiedClassType() || ToPtr2->getInterfaceDecl())) 3109 return ImplicitConversionSequence::Worse; 3110 if (ToPtr2->isObjCClassType() && 3111 (ToPtr1->isObjCQualifiedClassType() || ToPtr1->getInterfaceDecl())) 3112 return ImplicitConversionSequence::Better; 3113 3114 // A conversion to a non-Class object pointer type is better than a 3115 // conversion to a qualified 'Class' type. 3116 if (ToPtr1->isObjCQualifiedClassType() && ToPtr2->getInterfaceDecl()) 3117 return ImplicitConversionSequence::Worse; 3118 if (ToPtr2->isObjCQualifiedClassType() && ToPtr1->getInterfaceDecl()) 3119 return ImplicitConversionSequence::Better; 3120 3121 // -- "conversion of C* to B* is better than conversion of C* to A*," 3122 if (S.Context.hasSameType(FromType1, FromType2) && 3123 !FromPtr1->isObjCIdType() && !FromPtr1->isObjCClassType() && 3124 (ToAssignLeft != ToAssignRight)) 3125 return ToAssignLeft? ImplicitConversionSequence::Worse 3126 : ImplicitConversionSequence::Better; 3127 3128 // -- "conversion of B* to A* is better than conversion of C* to A*," 3129 if (S.Context.hasSameUnqualifiedType(ToType1, ToType2) && 3130 (FromAssignLeft != FromAssignRight)) 3131 return FromAssignLeft? ImplicitConversionSequence::Better 3132 : ImplicitConversionSequence::Worse; 3133 } 3134 } 3135 3136 // Ranking of member-pointer types. 3137 if (SCS1.Second == ICK_Pointer_Member && SCS2.Second == ICK_Pointer_Member && 3138 FromType1->isMemberPointerType() && FromType2->isMemberPointerType() && 3139 ToType1->isMemberPointerType() && ToType2->isMemberPointerType()) { 3140 const MemberPointerType * FromMemPointer1 = 3141 FromType1->getAs<MemberPointerType>(); 3142 const MemberPointerType * ToMemPointer1 = 3143 ToType1->getAs<MemberPointerType>(); 3144 const MemberPointerType * FromMemPointer2 = 3145 FromType2->getAs<MemberPointerType>(); 3146 const MemberPointerType * ToMemPointer2 = 3147 ToType2->getAs<MemberPointerType>(); 3148 const Type *FromPointeeType1 = FromMemPointer1->getClass(); 3149 const Type *ToPointeeType1 = ToMemPointer1->getClass(); 3150 const Type *FromPointeeType2 = FromMemPointer2->getClass(); 3151 const Type *ToPointeeType2 = ToMemPointer2->getClass(); 3152 QualType FromPointee1 = QualType(FromPointeeType1, 0).getUnqualifiedType(); 3153 QualType ToPointee1 = QualType(ToPointeeType1, 0).getUnqualifiedType(); 3154 QualType FromPointee2 = QualType(FromPointeeType2, 0).getUnqualifiedType(); 3155 QualType ToPointee2 = QualType(ToPointeeType2, 0).getUnqualifiedType(); 3156 // conversion of A::* to B::* is better than conversion of A::* to C::*, 3157 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 3158 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 3159 return ImplicitConversionSequence::Worse; 3160 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 3161 return ImplicitConversionSequence::Better; 3162 } 3163 // conversion of B::* to C::* is better than conversion of A::* to C::* 3164 if (ToPointee1 == ToPointee2 && FromPointee1 != FromPointee2) { 3165 if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 3166 return ImplicitConversionSequence::Better; 3167 else if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 3168 return ImplicitConversionSequence::Worse; 3169 } 3170 } 3171 3172 if (SCS1.Second == ICK_Derived_To_Base) { 3173 // -- conversion of C to B is better than conversion of C to A, 3174 // -- binding of an expression of type C to a reference of type 3175 // B& is better than binding an expression of type C to a 3176 // reference of type A&, 3177 if (S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3178 !S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3179 if (S.IsDerivedFrom(ToType1, ToType2)) 3180 return ImplicitConversionSequence::Better; 3181 else if (S.IsDerivedFrom(ToType2, ToType1)) 3182 return ImplicitConversionSequence::Worse; 3183 } 3184 3185 // -- conversion of B to A is better than conversion of C to A. 3186 // -- binding of an expression of type B to a reference of type 3187 // A& is better than binding an expression of type C to a 3188 // reference of type A&, 3189 if (!S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3190 S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3191 if (S.IsDerivedFrom(FromType2, FromType1)) 3192 return ImplicitConversionSequence::Better; 3193 else if (S.IsDerivedFrom(FromType1, FromType2)) 3194 return ImplicitConversionSequence::Worse; 3195 } 3196 } 3197 3198 return ImplicitConversionSequence::Indistinguishable; 3199} 3200 3201/// CompareReferenceRelationship - Compare the two types T1 and T2 to 3202/// determine whether they are reference-related, 3203/// reference-compatible, reference-compatible with added 3204/// qualification, or incompatible, for use in C++ initialization by 3205/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 3206/// type, and the first type (T1) is the pointee type of the reference 3207/// type being initialized. 3208Sema::ReferenceCompareResult 3209Sema::CompareReferenceRelationship(SourceLocation Loc, 3210 QualType OrigT1, QualType OrigT2, 3211 bool &DerivedToBase, 3212 bool &ObjCConversion, 3213 bool &ObjCLifetimeConversion) { 3214 assert(!OrigT1->isReferenceType() && 3215 "T1 must be the pointee type of the reference type"); 3216 assert(!OrigT2->isReferenceType() && "T2 cannot be a reference type"); 3217 3218 QualType T1 = Context.getCanonicalType(OrigT1); 3219 QualType T2 = Context.getCanonicalType(OrigT2); 3220 Qualifiers T1Quals, T2Quals; 3221 QualType UnqualT1 = Context.getUnqualifiedArrayType(T1, T1Quals); 3222 QualType UnqualT2 = Context.getUnqualifiedArrayType(T2, T2Quals); 3223 3224 // C++ [dcl.init.ref]p4: 3225 // Given types "cv1 T1" and "cv2 T2," "cv1 T1" is 3226 // reference-related to "cv2 T2" if T1 is the same type as T2, or 3227 // T1 is a base class of T2. 3228 DerivedToBase = false; 3229 ObjCConversion = false; 3230 ObjCLifetimeConversion = false; 3231 if (UnqualT1 == UnqualT2) { 3232 // Nothing to do. 3233 } else if (!RequireCompleteType(Loc, OrigT2, PDiag()) && 3234 IsDerivedFrom(UnqualT2, UnqualT1)) 3235 DerivedToBase = true; 3236 else if (UnqualT1->isObjCObjectOrInterfaceType() && 3237 UnqualT2->isObjCObjectOrInterfaceType() && 3238 Context.canBindObjCObjectType(UnqualT1, UnqualT2)) 3239 ObjCConversion = true; 3240 else 3241 return Ref_Incompatible; 3242 3243 // At this point, we know that T1 and T2 are reference-related (at 3244 // least). 3245 3246 // If the type is an array type, promote the element qualifiers to the type 3247 // for comparison. 3248 if (isa<ArrayType>(T1) && T1Quals) 3249 T1 = Context.getQualifiedType(UnqualT1, T1Quals); 3250 if (isa<ArrayType>(T2) && T2Quals) 3251 T2 = Context.getQualifiedType(UnqualT2, T2Quals); 3252 3253 // C++ [dcl.init.ref]p4: 3254 // "cv1 T1" is reference-compatible with "cv2 T2" if T1 is 3255 // reference-related to T2 and cv1 is the same cv-qualification 3256 // as, or greater cv-qualification than, cv2. For purposes of 3257 // overload resolution, cases for which cv1 is greater 3258 // cv-qualification than cv2 are identified as 3259 // reference-compatible with added qualification (see 13.3.3.2). 3260 // 3261 // Note that we also require equivalence of Objective-C GC and address-space 3262 // qualifiers when performing these computations, so that e.g., an int in 3263 // address space 1 is not reference-compatible with an int in address 3264 // space 2. 3265 if (T1Quals.getObjCLifetime() != T2Quals.getObjCLifetime() && 3266 T1Quals.compatiblyIncludesObjCLifetime(T2Quals)) { 3267 T1Quals.removeObjCLifetime(); 3268 T2Quals.removeObjCLifetime(); 3269 ObjCLifetimeConversion = true; 3270 } 3271 3272 if (T1Quals == T2Quals) 3273 return Ref_Compatible; 3274 else if (T1Quals.compatiblyIncludes(T2Quals)) 3275 return Ref_Compatible_With_Added_Qualification; 3276 else 3277 return Ref_Related; 3278} 3279 3280/// \brief Look for a user-defined conversion to an value reference-compatible 3281/// with DeclType. Return true if something definite is found. 3282static bool 3283FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS, 3284 QualType DeclType, SourceLocation DeclLoc, 3285 Expr *Init, QualType T2, bool AllowRvalues, 3286 bool AllowExplicit) { 3287 assert(T2->isRecordType() && "Can only find conversions of record types."); 3288 CXXRecordDecl *T2RecordDecl 3289 = dyn_cast<CXXRecordDecl>(T2->getAs<RecordType>()->getDecl()); 3290 3291 OverloadCandidateSet CandidateSet(DeclLoc); 3292 const UnresolvedSetImpl *Conversions 3293 = T2RecordDecl->getVisibleConversionFunctions(); 3294 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 3295 E = Conversions->end(); I != E; ++I) { 3296 NamedDecl *D = *I; 3297 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 3298 if (isa<UsingShadowDecl>(D)) 3299 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 3300 3301 FunctionTemplateDecl *ConvTemplate 3302 = dyn_cast<FunctionTemplateDecl>(D); 3303 CXXConversionDecl *Conv; 3304 if (ConvTemplate) 3305 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 3306 else 3307 Conv = cast<CXXConversionDecl>(D); 3308 3309 // If this is an explicit conversion, and we're not allowed to consider 3310 // explicit conversions, skip it. 3311 if (!AllowExplicit && Conv->isExplicit()) 3312 continue; 3313 3314 if (AllowRvalues) { 3315 bool DerivedToBase = false; 3316 bool ObjCConversion = false; 3317 bool ObjCLifetimeConversion = false; 3318 if (!ConvTemplate && 3319 S.CompareReferenceRelationship( 3320 DeclLoc, 3321 Conv->getConversionType().getNonReferenceType() 3322 .getUnqualifiedType(), 3323 DeclType.getNonReferenceType().getUnqualifiedType(), 3324 DerivedToBase, ObjCConversion, ObjCLifetimeConversion) == 3325 Sema::Ref_Incompatible) 3326 continue; 3327 } else { 3328 // If the conversion function doesn't return a reference type, 3329 // it can't be considered for this conversion. An rvalue reference 3330 // is only acceptable if its referencee is a function type. 3331 3332 const ReferenceType *RefType = 3333 Conv->getConversionType()->getAs<ReferenceType>(); 3334 if (!RefType || 3335 (!RefType->isLValueReferenceType() && 3336 !RefType->getPointeeType()->isFunctionType())) 3337 continue; 3338 } 3339 3340 if (ConvTemplate) 3341 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), ActingDC, 3342 Init, DeclType, CandidateSet); 3343 else 3344 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Init, 3345 DeclType, CandidateSet); 3346 } 3347 3348 OverloadCandidateSet::iterator Best; 3349 switch (CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) { 3350 case OR_Success: 3351 // C++ [over.ics.ref]p1: 3352 // 3353 // [...] If the parameter binds directly to the result of 3354 // applying a conversion function to the argument 3355 // expression, the implicit conversion sequence is a 3356 // user-defined conversion sequence (13.3.3.1.2), with the 3357 // second standard conversion sequence either an identity 3358 // conversion or, if the conversion function returns an 3359 // entity of a type that is a derived class of the parameter 3360 // type, a derived-to-base Conversion. 3361 if (!Best->FinalConversion.DirectBinding) 3362 return false; 3363 3364 if (Best->Function) 3365 S.MarkDeclarationReferenced(DeclLoc, Best->Function); 3366 ICS.setUserDefined(); 3367 ICS.UserDefined.Before = Best->Conversions[0].Standard; 3368 ICS.UserDefined.After = Best->FinalConversion; 3369 ICS.UserDefined.ConversionFunction = Best->Function; 3370 ICS.UserDefined.FoundConversionFunction = Best->FoundDecl; 3371 ICS.UserDefined.EllipsisConversion = false; 3372 assert(ICS.UserDefined.After.ReferenceBinding && 3373 ICS.UserDefined.After.DirectBinding && 3374 "Expected a direct reference binding!"); 3375 return true; 3376 3377 case OR_Ambiguous: 3378 ICS.setAmbiguous(); 3379 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(); 3380 Cand != CandidateSet.end(); ++Cand) 3381 if (Cand->Viable) 3382 ICS.Ambiguous.addConversion(Cand->Function); 3383 return true; 3384 3385 case OR_No_Viable_Function: 3386 case OR_Deleted: 3387 // There was no suitable conversion, or we found a deleted 3388 // conversion; continue with other checks. 3389 return false; 3390 } 3391 3392 return false; 3393} 3394 3395/// \brief Compute an implicit conversion sequence for reference 3396/// initialization. 3397static ImplicitConversionSequence 3398TryReferenceInit(Sema &S, Expr *&Init, QualType DeclType, 3399 SourceLocation DeclLoc, 3400 bool SuppressUserConversions, 3401 bool AllowExplicit) { 3402 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 3403 3404 // Most paths end in a failed conversion. 3405 ImplicitConversionSequence ICS; 3406 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3407 3408 QualType T1 = DeclType->getAs<ReferenceType>()->getPointeeType(); 3409 QualType T2 = Init->getType(); 3410 3411 // If the initializer is the address of an overloaded function, try 3412 // to resolve the overloaded function. If all goes well, T2 is the 3413 // type of the resulting function. 3414 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) { 3415 DeclAccessPair Found; 3416 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Init, DeclType, 3417 false, Found)) 3418 T2 = Fn->getType(); 3419 } 3420 3421 // Compute some basic properties of the types and the initializer. 3422 bool isRValRef = DeclType->isRValueReferenceType(); 3423 bool DerivedToBase = false; 3424 bool ObjCConversion = false; 3425 bool ObjCLifetimeConversion = false; 3426 Expr::Classification InitCategory = Init->Classify(S.Context); 3427 Sema::ReferenceCompareResult RefRelationship 3428 = S.CompareReferenceRelationship(DeclLoc, T1, T2, DerivedToBase, 3429 ObjCConversion, ObjCLifetimeConversion); 3430 3431 3432 // C++0x [dcl.init.ref]p5: 3433 // A reference to type "cv1 T1" is initialized by an expression 3434 // of type "cv2 T2" as follows: 3435 3436 // -- If reference is an lvalue reference and the initializer expression 3437 if (!isRValRef) { 3438 // -- is an lvalue (but is not a bit-field), and "cv1 T1" is 3439 // reference-compatible with "cv2 T2," or 3440 // 3441 // Per C++ [over.ics.ref]p4, we don't check the bit-field property here. 3442 if (InitCategory.isLValue() && 3443 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 3444 // C++ [over.ics.ref]p1: 3445 // When a parameter of reference type binds directly (8.5.3) 3446 // to an argument expression, the implicit conversion sequence 3447 // is the identity conversion, unless the argument expression 3448 // has a type that is a derived class of the parameter type, 3449 // in which case the implicit conversion sequence is a 3450 // derived-to-base Conversion (13.3.3.1). 3451 ICS.setStandard(); 3452 ICS.Standard.First = ICK_Identity; 3453 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3454 : ObjCConversion? ICK_Compatible_Conversion 3455 : ICK_Identity; 3456 ICS.Standard.Third = ICK_Identity; 3457 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3458 ICS.Standard.setToType(0, T2); 3459 ICS.Standard.setToType(1, T1); 3460 ICS.Standard.setToType(2, T1); 3461 ICS.Standard.ReferenceBinding = true; 3462 ICS.Standard.DirectBinding = true; 3463 ICS.Standard.IsLvalueReference = !isRValRef; 3464 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3465 ICS.Standard.BindsToRvalue = false; 3466 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3467 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion; 3468 ICS.Standard.CopyConstructor = 0; 3469 3470 // Nothing more to do: the inaccessibility/ambiguity check for 3471 // derived-to-base conversions is suppressed when we're 3472 // computing the implicit conversion sequence (C++ 3473 // [over.best.ics]p2). 3474 return ICS; 3475 } 3476 3477 // -- has a class type (i.e., T2 is a class type), where T1 is 3478 // not reference-related to T2, and can be implicitly 3479 // converted to an lvalue of type "cv3 T3," where "cv1 T1" 3480 // is reference-compatible with "cv3 T3" 92) (this 3481 // conversion is selected by enumerating the applicable 3482 // conversion functions (13.3.1.6) and choosing the best 3483 // one through overload resolution (13.3)), 3484 if (!SuppressUserConversions && T2->isRecordType() && 3485 !S.RequireCompleteType(DeclLoc, T2, 0) && 3486 RefRelationship == Sema::Ref_Incompatible) { 3487 if (FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3488 Init, T2, /*AllowRvalues=*/false, 3489 AllowExplicit)) 3490 return ICS; 3491 } 3492 } 3493 3494 // -- Otherwise, the reference shall be an lvalue reference to a 3495 // non-volatile const type (i.e., cv1 shall be const), or the reference 3496 // shall be an rvalue reference. 3497 // 3498 // We actually handle one oddity of C++ [over.ics.ref] at this 3499 // point, which is that, due to p2 (which short-circuits reference 3500 // binding by only attempting a simple conversion for non-direct 3501 // bindings) and p3's strange wording, we allow a const volatile 3502 // reference to bind to an rvalue. Hence the check for the presence 3503 // of "const" rather than checking for "const" being the only 3504 // qualifier. 3505 // This is also the point where rvalue references and lvalue inits no longer 3506 // go together. 3507 if (!isRValRef && !T1.isConstQualified()) 3508 return ICS; 3509 3510 // -- If the initializer expression 3511 // 3512 // -- is an xvalue, class prvalue, array prvalue or function 3513 // lvalue and "cv1 T1" is reference-compatible with "cv2 T2", or 3514 if (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification && 3515 (InitCategory.isXValue() || 3516 (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) || 3517 (InitCategory.isLValue() && T2->isFunctionType()))) { 3518 ICS.setStandard(); 3519 ICS.Standard.First = ICK_Identity; 3520 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3521 : ObjCConversion? ICK_Compatible_Conversion 3522 : ICK_Identity; 3523 ICS.Standard.Third = ICK_Identity; 3524 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3525 ICS.Standard.setToType(0, T2); 3526 ICS.Standard.setToType(1, T1); 3527 ICS.Standard.setToType(2, T1); 3528 ICS.Standard.ReferenceBinding = true; 3529 // In C++0x, this is always a direct binding. In C++98/03, it's a direct 3530 // binding unless we're binding to a class prvalue. 3531 // Note: Although xvalues wouldn't normally show up in C++98/03 code, we 3532 // allow the use of rvalue references in C++98/03 for the benefit of 3533 // standard library implementors; therefore, we need the xvalue check here. 3534 ICS.Standard.DirectBinding = 3535 S.getLangOptions().CPlusPlus0x || 3536 (InitCategory.isPRValue() && !T2->isRecordType()); 3537 ICS.Standard.IsLvalueReference = !isRValRef; 3538 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3539 ICS.Standard.BindsToRvalue = InitCategory.isRValue(); 3540 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3541 ICS.Standard.ObjCLifetimeConversionBinding = ObjCLifetimeConversion; 3542 ICS.Standard.CopyConstructor = 0; 3543 return ICS; 3544 } 3545 3546 // -- has a class type (i.e., T2 is a class type), where T1 is not 3547 // reference-related to T2, and can be implicitly converted to 3548 // an xvalue, class prvalue, or function lvalue of type 3549 // "cv3 T3", where "cv1 T1" is reference-compatible with 3550 // "cv3 T3", 3551 // 3552 // then the reference is bound to the value of the initializer 3553 // expression in the first case and to the result of the conversion 3554 // in the second case (or, in either case, to an appropriate base 3555 // class subobject). 3556 if (!SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3557 T2->isRecordType() && !S.RequireCompleteType(DeclLoc, T2, 0) && 3558 FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3559 Init, T2, /*AllowRvalues=*/true, 3560 AllowExplicit)) { 3561 // In the second case, if the reference is an rvalue reference 3562 // and the second standard conversion sequence of the 3563 // user-defined conversion sequence includes an lvalue-to-rvalue 3564 // conversion, the program is ill-formed. 3565 if (ICS.isUserDefined() && isRValRef && 3566 ICS.UserDefined.After.First == ICK_Lvalue_To_Rvalue) 3567 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3568 3569 return ICS; 3570 } 3571 3572 // -- Otherwise, a temporary of type "cv1 T1" is created and 3573 // initialized from the initializer expression using the 3574 // rules for a non-reference copy initialization (8.5). The 3575 // reference is then bound to the temporary. If T1 is 3576 // reference-related to T2, cv1 must be the same 3577 // cv-qualification as, or greater cv-qualification than, 3578 // cv2; otherwise, the program is ill-formed. 3579 if (RefRelationship == Sema::Ref_Related) { 3580 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 3581 // we would be reference-compatible or reference-compatible with 3582 // added qualification. But that wasn't the case, so the reference 3583 // initialization fails. 3584 // 3585 // Note that we only want to check address spaces and cvr-qualifiers here. 3586 // ObjC GC and lifetime qualifiers aren't important. 3587 Qualifiers T1Quals = T1.getQualifiers(); 3588 Qualifiers T2Quals = T2.getQualifiers(); 3589 T1Quals.removeObjCGCAttr(); 3590 T1Quals.removeObjCLifetime(); 3591 T2Quals.removeObjCGCAttr(); 3592 T2Quals.removeObjCLifetime(); 3593 if (!T1Quals.compatiblyIncludes(T2Quals)) 3594 return ICS; 3595 } 3596 3597 // If at least one of the types is a class type, the types are not 3598 // related, and we aren't allowed any user conversions, the 3599 // reference binding fails. This case is important for breaking 3600 // recursion, since TryImplicitConversion below will attempt to 3601 // create a temporary through the use of a copy constructor. 3602 if (SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3603 (T1->isRecordType() || T2->isRecordType())) 3604 return ICS; 3605 3606 // If T1 is reference-related to T2 and the reference is an rvalue 3607 // reference, the initializer expression shall not be an lvalue. 3608 if (RefRelationship >= Sema::Ref_Related && 3609 isRValRef && Init->Classify(S.Context).isLValue()) 3610 return ICS; 3611 3612 // C++ [over.ics.ref]p2: 3613 // When a parameter of reference type is not bound directly to 3614 // an argument expression, the conversion sequence is the one 3615 // required to convert the argument expression to the 3616 // underlying type of the reference according to 3617 // 13.3.3.1. Conceptually, this conversion sequence corresponds 3618 // to copy-initializing a temporary of the underlying type with 3619 // the argument expression. Any difference in top-level 3620 // cv-qualification is subsumed by the initialization itself 3621 // and does not constitute a conversion. 3622 ICS = TryImplicitConversion(S, Init, T1, SuppressUserConversions, 3623 /*AllowExplicit=*/false, 3624 /*InOverloadResolution=*/false, 3625 /*CStyle=*/false, 3626 /*AllowObjCWritebackConversion=*/false); 3627 3628 // Of course, that's still a reference binding. 3629 if (ICS.isStandard()) { 3630 ICS.Standard.ReferenceBinding = true; 3631 ICS.Standard.IsLvalueReference = !isRValRef; 3632 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3633 ICS.Standard.BindsToRvalue = true; 3634 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3635 ICS.Standard.ObjCLifetimeConversionBinding = false; 3636 } else if (ICS.isUserDefined()) { 3637 ICS.UserDefined.After.ReferenceBinding = true; 3638 ICS.UserDefined.After.IsLvalueReference = !isRValRef; 3639 ICS.UserDefined.After.BindsToFunctionLvalue = T2->isFunctionType(); 3640 ICS.UserDefined.After.BindsToRvalue = true; 3641 ICS.UserDefined.After.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3642 ICS.UserDefined.After.ObjCLifetimeConversionBinding = false; 3643 } 3644 3645 return ICS; 3646} 3647 3648/// TryCopyInitialization - Try to copy-initialize a value of type 3649/// ToType from the expression From. Return the implicit conversion 3650/// sequence required to pass this argument, which may be a bad 3651/// conversion sequence (meaning that the argument cannot be passed to 3652/// a parameter of this type). If @p SuppressUserConversions, then we 3653/// do not permit any user-defined conversion sequences. 3654static ImplicitConversionSequence 3655TryCopyInitialization(Sema &S, Expr *From, QualType ToType, 3656 bool SuppressUserConversions, 3657 bool InOverloadResolution, 3658 bool AllowObjCWritebackConversion) { 3659 if (ToType->isReferenceType()) 3660 return TryReferenceInit(S, From, ToType, 3661 /*FIXME:*/From->getLocStart(), 3662 SuppressUserConversions, 3663 /*AllowExplicit=*/false); 3664 3665 return TryImplicitConversion(S, From, ToType, 3666 SuppressUserConversions, 3667 /*AllowExplicit=*/false, 3668 InOverloadResolution, 3669 /*CStyle=*/false, 3670 AllowObjCWritebackConversion); 3671} 3672 3673static bool TryCopyInitialization(const CanQualType FromQTy, 3674 const CanQualType ToQTy, 3675 Sema &S, 3676 SourceLocation Loc, 3677 ExprValueKind FromVK) { 3678 OpaqueValueExpr TmpExpr(Loc, FromQTy, FromVK); 3679 ImplicitConversionSequence ICS = 3680 TryCopyInitialization(S, &TmpExpr, ToQTy, true, true, false); 3681 3682 return !ICS.isBad(); 3683} 3684 3685/// TryObjectArgumentInitialization - Try to initialize the object 3686/// parameter of the given member function (@c Method) from the 3687/// expression @p From. 3688static ImplicitConversionSequence 3689TryObjectArgumentInitialization(Sema &S, QualType OrigFromType, 3690 Expr::Classification FromClassification, 3691 CXXMethodDecl *Method, 3692 CXXRecordDecl *ActingContext) { 3693 QualType ClassType = S.Context.getTypeDeclType(ActingContext); 3694 // [class.dtor]p2: A destructor can be invoked for a const, volatile or 3695 // const volatile object. 3696 unsigned Quals = isa<CXXDestructorDecl>(Method) ? 3697 Qualifiers::Const | Qualifiers::Volatile : Method->getTypeQualifiers(); 3698 QualType ImplicitParamType = S.Context.getCVRQualifiedType(ClassType, Quals); 3699 3700 // Set up the conversion sequence as a "bad" conversion, to allow us 3701 // to exit early. 3702 ImplicitConversionSequence ICS; 3703 3704 // We need to have an object of class type. 3705 QualType FromType = OrigFromType; 3706 if (const PointerType *PT = FromType->getAs<PointerType>()) { 3707 FromType = PT->getPointeeType(); 3708 3709 // When we had a pointer, it's implicitly dereferenced, so we 3710 // better have an lvalue. 3711 assert(FromClassification.isLValue()); 3712 } 3713 3714 assert(FromType->isRecordType()); 3715 3716 // C++0x [over.match.funcs]p4: 3717 // For non-static member functions, the type of the implicit object 3718 // parameter is 3719 // 3720 // - "lvalue reference to cv X" for functions declared without a 3721 // ref-qualifier or with the & ref-qualifier 3722 // - "rvalue reference to cv X" for functions declared with the && 3723 // ref-qualifier 3724 // 3725 // where X is the class of which the function is a member and cv is the 3726 // cv-qualification on the member function declaration. 3727 // 3728 // However, when finding an implicit conversion sequence for the argument, we 3729 // are not allowed to create temporaries or perform user-defined conversions 3730 // (C++ [over.match.funcs]p5). We perform a simplified version of 3731 // reference binding here, that allows class rvalues to bind to 3732 // non-constant references. 3733 3734 // First check the qualifiers. 3735 QualType FromTypeCanon = S.Context.getCanonicalType(FromType); 3736 if (ImplicitParamType.getCVRQualifiers() 3737 != FromTypeCanon.getLocalCVRQualifiers() && 3738 !ImplicitParamType.isAtLeastAsQualifiedAs(FromTypeCanon)) { 3739 ICS.setBad(BadConversionSequence::bad_qualifiers, 3740 OrigFromType, ImplicitParamType); 3741 return ICS; 3742 } 3743 3744 // Check that we have either the same type or a derived type. It 3745 // affects the conversion rank. 3746 QualType ClassTypeCanon = S.Context.getCanonicalType(ClassType); 3747 ImplicitConversionKind SecondKind; 3748 if (ClassTypeCanon == FromTypeCanon.getLocalUnqualifiedType()) { 3749 SecondKind = ICK_Identity; 3750 } else if (S.IsDerivedFrom(FromType, ClassType)) 3751 SecondKind = ICK_Derived_To_Base; 3752 else { 3753 ICS.setBad(BadConversionSequence::unrelated_class, 3754 FromType, ImplicitParamType); 3755 return ICS; 3756 } 3757 3758 // Check the ref-qualifier. 3759 switch (Method->getRefQualifier()) { 3760 case RQ_None: 3761 // Do nothing; we don't care about lvalueness or rvalueness. 3762 break; 3763 3764 case RQ_LValue: 3765 if (!FromClassification.isLValue() && Quals != Qualifiers::Const) { 3766 // non-const lvalue reference cannot bind to an rvalue 3767 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, FromType, 3768 ImplicitParamType); 3769 return ICS; 3770 } 3771 break; 3772 3773 case RQ_RValue: 3774 if (!FromClassification.isRValue()) { 3775 // rvalue reference cannot bind to an lvalue 3776 ICS.setBad(BadConversionSequence::rvalue_ref_to_lvalue, FromType, 3777 ImplicitParamType); 3778 return ICS; 3779 } 3780 break; 3781 } 3782 3783 // Success. Mark this as a reference binding. 3784 ICS.setStandard(); 3785 ICS.Standard.setAsIdentityConversion(); 3786 ICS.Standard.Second = SecondKind; 3787 ICS.Standard.setFromType(FromType); 3788 ICS.Standard.setAllToTypes(ImplicitParamType); 3789 ICS.Standard.ReferenceBinding = true; 3790 ICS.Standard.DirectBinding = true; 3791 ICS.Standard.IsLvalueReference = Method->getRefQualifier() != RQ_RValue; 3792 ICS.Standard.BindsToFunctionLvalue = false; 3793 ICS.Standard.BindsToRvalue = FromClassification.isRValue(); 3794 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier 3795 = (Method->getRefQualifier() == RQ_None); 3796 return ICS; 3797} 3798 3799/// PerformObjectArgumentInitialization - Perform initialization of 3800/// the implicit object parameter for the given Method with the given 3801/// expression. 3802ExprResult 3803Sema::PerformObjectArgumentInitialization(Expr *From, 3804 NestedNameSpecifier *Qualifier, 3805 NamedDecl *FoundDecl, 3806 CXXMethodDecl *Method) { 3807 QualType FromRecordType, DestType; 3808 QualType ImplicitParamRecordType = 3809 Method->getThisType(Context)->getAs<PointerType>()->getPointeeType(); 3810 3811 Expr::Classification FromClassification; 3812 if (const PointerType *PT = From->getType()->getAs<PointerType>()) { 3813 FromRecordType = PT->getPointeeType(); 3814 DestType = Method->getThisType(Context); 3815 FromClassification = Expr::Classification::makeSimpleLValue(); 3816 } else { 3817 FromRecordType = From->getType(); 3818 DestType = ImplicitParamRecordType; 3819 FromClassification = From->Classify(Context); 3820 } 3821 3822 // Note that we always use the true parent context when performing 3823 // the actual argument initialization. 3824 ImplicitConversionSequence ICS 3825 = TryObjectArgumentInitialization(*this, From->getType(), FromClassification, 3826 Method, Method->getParent()); 3827 if (ICS.isBad()) { 3828 if (ICS.Bad.Kind == BadConversionSequence::bad_qualifiers) { 3829 Qualifiers FromQs = FromRecordType.getQualifiers(); 3830 Qualifiers ToQs = DestType.getQualifiers(); 3831 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 3832 if (CVR) { 3833 Diag(From->getSourceRange().getBegin(), 3834 diag::err_member_function_call_bad_cvr) 3835 << Method->getDeclName() << FromRecordType << (CVR - 1) 3836 << From->getSourceRange(); 3837 Diag(Method->getLocation(), diag::note_previous_decl) 3838 << Method->getDeclName(); 3839 return ExprError(); 3840 } 3841 } 3842 3843 return Diag(From->getSourceRange().getBegin(), 3844 diag::err_implicit_object_parameter_init) 3845 << ImplicitParamRecordType << FromRecordType << From->getSourceRange(); 3846 } 3847 3848 if (ICS.Standard.Second == ICK_Derived_To_Base) { 3849 ExprResult FromRes = 3850 PerformObjectMemberConversion(From, Qualifier, FoundDecl, Method); 3851 if (FromRes.isInvalid()) 3852 return ExprError(); 3853 From = FromRes.take(); 3854 } 3855 3856 if (!Context.hasSameType(From->getType(), DestType)) 3857 From = ImpCastExprToType(From, DestType, CK_NoOp, 3858 From->getType()->isPointerType() ? VK_RValue : VK_LValue).take(); 3859 return Owned(From); 3860} 3861 3862/// TryContextuallyConvertToBool - Attempt to contextually convert the 3863/// expression From to bool (C++0x [conv]p3). 3864static ImplicitConversionSequence 3865TryContextuallyConvertToBool(Sema &S, Expr *From) { 3866 // FIXME: This is pretty broken. 3867 return TryImplicitConversion(S, From, S.Context.BoolTy, 3868 // FIXME: Are these flags correct? 3869 /*SuppressUserConversions=*/false, 3870 /*AllowExplicit=*/true, 3871 /*InOverloadResolution=*/false, 3872 /*CStyle=*/false, 3873 /*AllowObjCWritebackConversion=*/false); 3874} 3875 3876/// PerformContextuallyConvertToBool - Perform a contextual conversion 3877/// of the expression From to bool (C++0x [conv]p3). 3878ExprResult Sema::PerformContextuallyConvertToBool(Expr *From) { 3879 ImplicitConversionSequence ICS = TryContextuallyConvertToBool(*this, From); 3880 if (!ICS.isBad()) 3881 return PerformImplicitConversion(From, Context.BoolTy, ICS, AA_Converting); 3882 3883 if (!DiagnoseMultipleUserDefinedConversion(From, Context.BoolTy)) 3884 return Diag(From->getSourceRange().getBegin(), 3885 diag::err_typecheck_bool_condition) 3886 << From->getType() << From->getSourceRange(); 3887 return ExprError(); 3888} 3889 3890/// dropPointerConversions - If the given standard conversion sequence 3891/// involves any pointer conversions, remove them. This may change 3892/// the result type of the conversion sequence. 3893static void dropPointerConversion(StandardConversionSequence &SCS) { 3894 if (SCS.Second == ICK_Pointer_Conversion) { 3895 SCS.Second = ICK_Identity; 3896 SCS.Third = ICK_Identity; 3897 SCS.ToTypePtrs[2] = SCS.ToTypePtrs[1] = SCS.ToTypePtrs[0]; 3898 } 3899} 3900 3901/// TryContextuallyConvertToObjCPointer - Attempt to contextually 3902/// convert the expression From to an Objective-C pointer type. 3903static ImplicitConversionSequence 3904TryContextuallyConvertToObjCPointer(Sema &S, Expr *From) { 3905 // Do an implicit conversion to 'id'. 3906 QualType Ty = S.Context.getObjCIdType(); 3907 ImplicitConversionSequence ICS 3908 = TryImplicitConversion(S, From, Ty, 3909 // FIXME: Are these flags correct? 3910 /*SuppressUserConversions=*/false, 3911 /*AllowExplicit=*/true, 3912 /*InOverloadResolution=*/false, 3913 /*CStyle=*/false, 3914 /*AllowObjCWritebackConversion=*/false); 3915 3916 // Strip off any final conversions to 'id'. 3917 switch (ICS.getKind()) { 3918 case ImplicitConversionSequence::BadConversion: 3919 case ImplicitConversionSequence::AmbiguousConversion: 3920 case ImplicitConversionSequence::EllipsisConversion: 3921 break; 3922 3923 case ImplicitConversionSequence::UserDefinedConversion: 3924 dropPointerConversion(ICS.UserDefined.After); 3925 break; 3926 3927 case ImplicitConversionSequence::StandardConversion: 3928 dropPointerConversion(ICS.Standard); 3929 break; 3930 } 3931 3932 return ICS; 3933} 3934 3935/// PerformContextuallyConvertToObjCPointer - Perform a contextual 3936/// conversion of the expression From to an Objective-C pointer type. 3937ExprResult Sema::PerformContextuallyConvertToObjCPointer(Expr *From) { 3938 QualType Ty = Context.getObjCIdType(); 3939 ImplicitConversionSequence ICS = 3940 TryContextuallyConvertToObjCPointer(*this, From); 3941 if (!ICS.isBad()) 3942 return PerformImplicitConversion(From, Ty, ICS, AA_Converting); 3943 return ExprError(); 3944} 3945 3946/// \brief Attempt to convert the given expression to an integral or 3947/// enumeration type. 3948/// 3949/// This routine will attempt to convert an expression of class type to an 3950/// integral or enumeration type, if that class type only has a single 3951/// conversion to an integral or enumeration type. 3952/// 3953/// \param Loc The source location of the construct that requires the 3954/// conversion. 3955/// 3956/// \param FromE The expression we're converting from. 3957/// 3958/// \param NotIntDiag The diagnostic to be emitted if the expression does not 3959/// have integral or enumeration type. 3960/// 3961/// \param IncompleteDiag The diagnostic to be emitted if the expression has 3962/// incomplete class type. 3963/// 3964/// \param ExplicitConvDiag The diagnostic to be emitted if we're calling an 3965/// explicit conversion function (because no implicit conversion functions 3966/// were available). This is a recovery mode. 3967/// 3968/// \param ExplicitConvNote The note to be emitted with \p ExplicitConvDiag, 3969/// showing which conversion was picked. 3970/// 3971/// \param AmbigDiag The diagnostic to be emitted if there is more than one 3972/// conversion function that could convert to integral or enumeration type. 3973/// 3974/// \param AmbigNote The note to be emitted with \p AmbigDiag for each 3975/// usable conversion function. 3976/// 3977/// \param ConvDiag The diagnostic to be emitted if we are calling a conversion 3978/// function, which may be an extension in this case. 3979/// 3980/// \returns The expression, converted to an integral or enumeration type if 3981/// successful. 3982ExprResult 3983Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From, 3984 const PartialDiagnostic &NotIntDiag, 3985 const PartialDiagnostic &IncompleteDiag, 3986 const PartialDiagnostic &ExplicitConvDiag, 3987 const PartialDiagnostic &ExplicitConvNote, 3988 const PartialDiagnostic &AmbigDiag, 3989 const PartialDiagnostic &AmbigNote, 3990 const PartialDiagnostic &ConvDiag) { 3991 // We can't perform any more checking for type-dependent expressions. 3992 if (From->isTypeDependent()) 3993 return Owned(From); 3994 3995 // If the expression already has integral or enumeration type, we're golden. 3996 QualType T = From->getType(); 3997 if (T->isIntegralOrEnumerationType()) 3998 return Owned(From); 3999 4000 // FIXME: Check for missing '()' if T is a function type? 4001 4002 // If we don't have a class type in C++, there's no way we can get an 4003 // expression of integral or enumeration type. 4004 const RecordType *RecordTy = T->getAs<RecordType>(); 4005 if (!RecordTy || !getLangOptions().CPlusPlus) { 4006 Diag(Loc, NotIntDiag) 4007 << T << From->getSourceRange(); 4008 return Owned(From); 4009 } 4010 4011 // We must have a complete class type. 4012 if (RequireCompleteType(Loc, T, IncompleteDiag)) 4013 return Owned(From); 4014 4015 // Look for a conversion to an integral or enumeration type. 4016 UnresolvedSet<4> ViableConversions; 4017 UnresolvedSet<4> ExplicitConversions; 4018 const UnresolvedSetImpl *Conversions 4019 = cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions(); 4020 4021 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 4022 E = Conversions->end(); 4023 I != E; 4024 ++I) { 4025 if (CXXConversionDecl *Conversion 4026 = dyn_cast<CXXConversionDecl>((*I)->getUnderlyingDecl())) 4027 if (Conversion->getConversionType().getNonReferenceType() 4028 ->isIntegralOrEnumerationType()) { 4029 if (Conversion->isExplicit()) 4030 ExplicitConversions.addDecl(I.getDecl(), I.getAccess()); 4031 else 4032 ViableConversions.addDecl(I.getDecl(), I.getAccess()); 4033 } 4034 } 4035 4036 switch (ViableConversions.size()) { 4037 case 0: 4038 if (ExplicitConversions.size() == 1) { 4039 DeclAccessPair Found = ExplicitConversions[0]; 4040 CXXConversionDecl *Conversion 4041 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 4042 4043 // The user probably meant to invoke the given explicit 4044 // conversion; use it. 4045 QualType ConvTy 4046 = Conversion->getConversionType().getNonReferenceType(); 4047 std::string TypeStr; 4048 ConvTy.getAsStringInternal(TypeStr, Context.PrintingPolicy); 4049 4050 Diag(Loc, ExplicitConvDiag) 4051 << T << ConvTy 4052 << FixItHint::CreateInsertion(From->getLocStart(), 4053 "static_cast<" + TypeStr + ">(") 4054 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(From->getLocEnd()), 4055 ")"); 4056 Diag(Conversion->getLocation(), ExplicitConvNote) 4057 << ConvTy->isEnumeralType() << ConvTy; 4058 4059 // If we aren't in a SFINAE context, build a call to the 4060 // explicit conversion function. 4061 if (isSFINAEContext()) 4062 return ExprError(); 4063 4064 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 4065 ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion); 4066 if (Result.isInvalid()) 4067 return ExprError(); 4068 4069 From = Result.get(); 4070 } 4071 4072 // We'll complain below about a non-integral condition type. 4073 break; 4074 4075 case 1: { 4076 // Apply this conversion. 4077 DeclAccessPair Found = ViableConversions[0]; 4078 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 4079 4080 CXXConversionDecl *Conversion 4081 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 4082 QualType ConvTy 4083 = Conversion->getConversionType().getNonReferenceType(); 4084 if (ConvDiag.getDiagID()) { 4085 if (isSFINAEContext()) 4086 return ExprError(); 4087 4088 Diag(Loc, ConvDiag) 4089 << T << ConvTy->isEnumeralType() << ConvTy << From->getSourceRange(); 4090 } 4091 4092 ExprResult Result = BuildCXXMemberCallExpr(From, Found, 4093 cast<CXXConversionDecl>(Found->getUnderlyingDecl())); 4094 if (Result.isInvalid()) 4095 return ExprError(); 4096 4097 From = Result.get(); 4098 break; 4099 } 4100 4101 default: 4102 Diag(Loc, AmbigDiag) 4103 << T << From->getSourceRange(); 4104 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) { 4105 CXXConversionDecl *Conv 4106 = cast<CXXConversionDecl>(ViableConversions[I]->getUnderlyingDecl()); 4107 QualType ConvTy = Conv->getConversionType().getNonReferenceType(); 4108 Diag(Conv->getLocation(), AmbigNote) 4109 << ConvTy->isEnumeralType() << ConvTy; 4110 } 4111 return Owned(From); 4112 } 4113 4114 if (!From->getType()->isIntegralOrEnumerationType()) 4115 Diag(Loc, NotIntDiag) 4116 << From->getType() << From->getSourceRange(); 4117 4118 return Owned(From); 4119} 4120 4121/// AddOverloadCandidate - Adds the given function to the set of 4122/// candidate functions, using the given function call arguments. If 4123/// @p SuppressUserConversions, then don't allow user-defined 4124/// conversions via constructors or conversion operators. 4125/// 4126/// \para PartialOverloading true if we are performing "partial" overloading 4127/// based on an incomplete set of function arguments. This feature is used by 4128/// code completion. 4129void 4130Sema::AddOverloadCandidate(FunctionDecl *Function, 4131 DeclAccessPair FoundDecl, 4132 Expr **Args, unsigned NumArgs, 4133 OverloadCandidateSet& CandidateSet, 4134 bool SuppressUserConversions, 4135 bool PartialOverloading) { 4136 const FunctionProtoType* Proto 4137 = dyn_cast<FunctionProtoType>(Function->getType()->getAs<FunctionType>()); 4138 assert(Proto && "Functions without a prototype cannot be overloaded"); 4139 assert(!Function->getDescribedFunctionTemplate() && 4140 "Use AddTemplateOverloadCandidate for function templates"); 4141 4142 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { 4143 if (!isa<CXXConstructorDecl>(Method)) { 4144 // If we get here, it's because we're calling a member function 4145 // that is named without a member access expression (e.g., 4146 // "this->f") that was either written explicitly or created 4147 // implicitly. This can happen with a qualified call to a member 4148 // function, e.g., X::f(). We use an empty type for the implied 4149 // object argument (C++ [over.call.func]p3), and the acting context 4150 // is irrelevant. 4151 AddMethodCandidate(Method, FoundDecl, Method->getParent(), 4152 QualType(), Expr::Classification::makeSimpleLValue(), 4153 Args, NumArgs, CandidateSet, 4154 SuppressUserConversions); 4155 return; 4156 } 4157 // We treat a constructor like a non-member function, since its object 4158 // argument doesn't participate in overload resolution. 4159 } 4160 4161 if (!CandidateSet.isNewCandidate(Function)) 4162 return; 4163 4164 // Overload resolution is always an unevaluated context. 4165 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4166 4167 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Function)){ 4168 // C++ [class.copy]p3: 4169 // A member function template is never instantiated to perform the copy 4170 // of a class object to an object of its class type. 4171 QualType ClassType = Context.getTypeDeclType(Constructor->getParent()); 4172 if (NumArgs == 1 && 4173 Constructor->isSpecializationCopyingObject() && 4174 (Context.hasSameUnqualifiedType(ClassType, Args[0]->getType()) || 4175 IsDerivedFrom(Args[0]->getType(), ClassType))) 4176 return; 4177 } 4178 4179 // Add this candidate 4180 CandidateSet.push_back(OverloadCandidate()); 4181 OverloadCandidate& Candidate = CandidateSet.back(); 4182 Candidate.FoundDecl = FoundDecl; 4183 Candidate.Function = Function; 4184 Candidate.Viable = true; 4185 Candidate.IsSurrogate = false; 4186 Candidate.IgnoreObjectArgument = false; 4187 Candidate.ExplicitCallArguments = NumArgs; 4188 4189 unsigned NumArgsInProto = Proto->getNumArgs(); 4190 4191 // (C++ 13.3.2p2): A candidate function having fewer than m 4192 // parameters is viable only if it has an ellipsis in its parameter 4193 // list (8.3.5). 4194 if ((NumArgs + (PartialOverloading && NumArgs)) > NumArgsInProto && 4195 !Proto->isVariadic()) { 4196 Candidate.Viable = false; 4197 Candidate.FailureKind = ovl_fail_too_many_arguments; 4198 return; 4199 } 4200 4201 // (C++ 13.3.2p2): A candidate function having more than m parameters 4202 // is viable only if the (m+1)st parameter has a default argument 4203 // (8.3.6). For the purposes of overload resolution, the 4204 // parameter list is truncated on the right, so that there are 4205 // exactly m parameters. 4206 unsigned MinRequiredArgs = Function->getMinRequiredArguments(); 4207 if (NumArgs < MinRequiredArgs && !PartialOverloading) { 4208 // Not enough arguments. 4209 Candidate.Viable = false; 4210 Candidate.FailureKind = ovl_fail_too_few_arguments; 4211 return; 4212 } 4213 4214 // Determine the implicit conversion sequences for each of the 4215 // arguments. 4216 Candidate.Conversions.resize(NumArgs); 4217 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4218 if (ArgIdx < NumArgsInProto) { 4219 // (C++ 13.3.2p3): for F to be a viable function, there shall 4220 // exist for each argument an implicit conversion sequence 4221 // (13.3.3.1) that converts that argument to the corresponding 4222 // parameter of F. 4223 QualType ParamType = Proto->getArgType(ArgIdx); 4224 Candidate.Conversions[ArgIdx] 4225 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4226 SuppressUserConversions, 4227 /*InOverloadResolution=*/true, 4228 /*AllowObjCWritebackConversion=*/ 4229 getLangOptions().ObjCAutoRefCount); 4230 if (Candidate.Conversions[ArgIdx].isBad()) { 4231 Candidate.Viable = false; 4232 Candidate.FailureKind = ovl_fail_bad_conversion; 4233 break; 4234 } 4235 } else { 4236 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4237 // argument for which there is no corresponding parameter is 4238 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4239 Candidate.Conversions[ArgIdx].setEllipsis(); 4240 } 4241 } 4242} 4243 4244/// \brief Add all of the function declarations in the given function set to 4245/// the overload canddiate set. 4246void Sema::AddFunctionCandidates(const UnresolvedSetImpl &Fns, 4247 Expr **Args, unsigned NumArgs, 4248 OverloadCandidateSet& CandidateSet, 4249 bool SuppressUserConversions) { 4250 for (UnresolvedSetIterator F = Fns.begin(), E = Fns.end(); F != E; ++F) { 4251 NamedDecl *D = F.getDecl()->getUnderlyingDecl(); 4252 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 4253 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 4254 AddMethodCandidate(cast<CXXMethodDecl>(FD), F.getPair(), 4255 cast<CXXMethodDecl>(FD)->getParent(), 4256 Args[0]->getType(), Args[0]->Classify(Context), 4257 Args + 1, NumArgs - 1, 4258 CandidateSet, SuppressUserConversions); 4259 else 4260 AddOverloadCandidate(FD, F.getPair(), Args, NumArgs, CandidateSet, 4261 SuppressUserConversions); 4262 } else { 4263 FunctionTemplateDecl *FunTmpl = cast<FunctionTemplateDecl>(D); 4264 if (isa<CXXMethodDecl>(FunTmpl->getTemplatedDecl()) && 4265 !cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl())->isStatic()) 4266 AddMethodTemplateCandidate(FunTmpl, F.getPair(), 4267 cast<CXXRecordDecl>(FunTmpl->getDeclContext()), 4268 /*FIXME: explicit args */ 0, 4269 Args[0]->getType(), 4270 Args[0]->Classify(Context), 4271 Args + 1, NumArgs - 1, 4272 CandidateSet, 4273 SuppressUserConversions); 4274 else 4275 AddTemplateOverloadCandidate(FunTmpl, F.getPair(), 4276 /*FIXME: explicit args */ 0, 4277 Args, NumArgs, CandidateSet, 4278 SuppressUserConversions); 4279 } 4280 } 4281} 4282 4283/// AddMethodCandidate - Adds a named decl (which is some kind of 4284/// method) as a method candidate to the given overload set. 4285void Sema::AddMethodCandidate(DeclAccessPair FoundDecl, 4286 QualType ObjectType, 4287 Expr::Classification ObjectClassification, 4288 Expr **Args, unsigned NumArgs, 4289 OverloadCandidateSet& CandidateSet, 4290 bool SuppressUserConversions) { 4291 NamedDecl *Decl = FoundDecl.getDecl(); 4292 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(Decl->getDeclContext()); 4293 4294 if (isa<UsingShadowDecl>(Decl)) 4295 Decl = cast<UsingShadowDecl>(Decl)->getTargetDecl(); 4296 4297 if (FunctionTemplateDecl *TD = dyn_cast<FunctionTemplateDecl>(Decl)) { 4298 assert(isa<CXXMethodDecl>(TD->getTemplatedDecl()) && 4299 "Expected a member function template"); 4300 AddMethodTemplateCandidate(TD, FoundDecl, ActingContext, 4301 /*ExplicitArgs*/ 0, 4302 ObjectType, ObjectClassification, Args, NumArgs, 4303 CandidateSet, 4304 SuppressUserConversions); 4305 } else { 4306 AddMethodCandidate(cast<CXXMethodDecl>(Decl), FoundDecl, ActingContext, 4307 ObjectType, ObjectClassification, Args, NumArgs, 4308 CandidateSet, SuppressUserConversions); 4309 } 4310} 4311 4312/// AddMethodCandidate - Adds the given C++ member function to the set 4313/// of candidate functions, using the given function call arguments 4314/// and the object argument (@c Object). For example, in a call 4315/// @c o.f(a1,a2), @c Object will contain @c o and @c Args will contain 4316/// both @c a1 and @c a2. If @p SuppressUserConversions, then don't 4317/// allow user-defined conversions via constructors or conversion 4318/// operators. 4319void 4320Sema::AddMethodCandidate(CXXMethodDecl *Method, DeclAccessPair FoundDecl, 4321 CXXRecordDecl *ActingContext, QualType ObjectType, 4322 Expr::Classification ObjectClassification, 4323 Expr **Args, unsigned NumArgs, 4324 OverloadCandidateSet& CandidateSet, 4325 bool SuppressUserConversions) { 4326 const FunctionProtoType* Proto 4327 = dyn_cast<FunctionProtoType>(Method->getType()->getAs<FunctionType>()); 4328 assert(Proto && "Methods without a prototype cannot be overloaded"); 4329 assert(!isa<CXXConstructorDecl>(Method) && 4330 "Use AddOverloadCandidate for constructors"); 4331 4332 if (!CandidateSet.isNewCandidate(Method)) 4333 return; 4334 4335 // Overload resolution is always an unevaluated context. 4336 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4337 4338 // Add this candidate 4339 CandidateSet.push_back(OverloadCandidate()); 4340 OverloadCandidate& Candidate = CandidateSet.back(); 4341 Candidate.FoundDecl = FoundDecl; 4342 Candidate.Function = Method; 4343 Candidate.IsSurrogate = false; 4344 Candidate.IgnoreObjectArgument = false; 4345 Candidate.ExplicitCallArguments = NumArgs; 4346 4347 unsigned NumArgsInProto = Proto->getNumArgs(); 4348 4349 // (C++ 13.3.2p2): A candidate function having fewer than m 4350 // parameters is viable only if it has an ellipsis in its parameter 4351 // list (8.3.5). 4352 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4353 Candidate.Viable = false; 4354 Candidate.FailureKind = ovl_fail_too_many_arguments; 4355 return; 4356 } 4357 4358 // (C++ 13.3.2p2): A candidate function having more than m parameters 4359 // is viable only if the (m+1)st parameter has a default argument 4360 // (8.3.6). For the purposes of overload resolution, the 4361 // parameter list is truncated on the right, so that there are 4362 // exactly m parameters. 4363 unsigned MinRequiredArgs = Method->getMinRequiredArguments(); 4364 if (NumArgs < MinRequiredArgs) { 4365 // Not enough arguments. 4366 Candidate.Viable = false; 4367 Candidate.FailureKind = ovl_fail_too_few_arguments; 4368 return; 4369 } 4370 4371 Candidate.Viable = true; 4372 Candidate.Conversions.resize(NumArgs + 1); 4373 4374 if (Method->isStatic() || ObjectType.isNull()) 4375 // The implicit object argument is ignored. 4376 Candidate.IgnoreObjectArgument = true; 4377 else { 4378 // Determine the implicit conversion sequence for the object 4379 // parameter. 4380 Candidate.Conversions[0] 4381 = TryObjectArgumentInitialization(*this, ObjectType, ObjectClassification, 4382 Method, ActingContext); 4383 if (Candidate.Conversions[0].isBad()) { 4384 Candidate.Viable = false; 4385 Candidate.FailureKind = ovl_fail_bad_conversion; 4386 return; 4387 } 4388 } 4389 4390 // Determine the implicit conversion sequences for each of the 4391 // arguments. 4392 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4393 if (ArgIdx < NumArgsInProto) { 4394 // (C++ 13.3.2p3): for F to be a viable function, there shall 4395 // exist for each argument an implicit conversion sequence 4396 // (13.3.3.1) that converts that argument to the corresponding 4397 // parameter of F. 4398 QualType ParamType = Proto->getArgType(ArgIdx); 4399 Candidate.Conversions[ArgIdx + 1] 4400 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4401 SuppressUserConversions, 4402 /*InOverloadResolution=*/true, 4403 /*AllowObjCWritebackConversion=*/ 4404 getLangOptions().ObjCAutoRefCount); 4405 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4406 Candidate.Viable = false; 4407 Candidate.FailureKind = ovl_fail_bad_conversion; 4408 break; 4409 } 4410 } else { 4411 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4412 // argument for which there is no corresponding parameter is 4413 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4414 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4415 } 4416 } 4417} 4418 4419/// \brief Add a C++ member function template as a candidate to the candidate 4420/// set, using template argument deduction to produce an appropriate member 4421/// function template specialization. 4422void 4423Sema::AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl, 4424 DeclAccessPair FoundDecl, 4425 CXXRecordDecl *ActingContext, 4426 TemplateArgumentListInfo *ExplicitTemplateArgs, 4427 QualType ObjectType, 4428 Expr::Classification ObjectClassification, 4429 Expr **Args, unsigned NumArgs, 4430 OverloadCandidateSet& CandidateSet, 4431 bool SuppressUserConversions) { 4432 if (!CandidateSet.isNewCandidate(MethodTmpl)) 4433 return; 4434 4435 // C++ [over.match.funcs]p7: 4436 // In each case where a candidate is a function template, candidate 4437 // function template specializations are generated using template argument 4438 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4439 // candidate functions in the usual way.113) A given name can refer to one 4440 // or more function templates and also to a set of overloaded non-template 4441 // functions. In such a case, the candidate functions generated from each 4442 // function template are combined with the set of non-template candidate 4443 // functions. 4444 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4445 FunctionDecl *Specialization = 0; 4446 if (TemplateDeductionResult Result 4447 = DeduceTemplateArguments(MethodTmpl, ExplicitTemplateArgs, 4448 Args, NumArgs, Specialization, Info)) { 4449 CandidateSet.push_back(OverloadCandidate()); 4450 OverloadCandidate &Candidate = CandidateSet.back(); 4451 Candidate.FoundDecl = FoundDecl; 4452 Candidate.Function = MethodTmpl->getTemplatedDecl(); 4453 Candidate.Viable = false; 4454 Candidate.FailureKind = ovl_fail_bad_deduction; 4455 Candidate.IsSurrogate = false; 4456 Candidate.IgnoreObjectArgument = false; 4457 Candidate.ExplicitCallArguments = NumArgs; 4458 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4459 Info); 4460 return; 4461 } 4462 4463 // Add the function template specialization produced by template argument 4464 // deduction as a candidate. 4465 assert(Specialization && "Missing member function template specialization?"); 4466 assert(isa<CXXMethodDecl>(Specialization) && 4467 "Specialization is not a member function?"); 4468 AddMethodCandidate(cast<CXXMethodDecl>(Specialization), FoundDecl, 4469 ActingContext, ObjectType, ObjectClassification, 4470 Args, NumArgs, CandidateSet, SuppressUserConversions); 4471} 4472 4473/// \brief Add a C++ function template specialization as a candidate 4474/// in the candidate set, using template argument deduction to produce 4475/// an appropriate function template specialization. 4476void 4477Sema::AddTemplateOverloadCandidate(FunctionTemplateDecl *FunctionTemplate, 4478 DeclAccessPair FoundDecl, 4479 TemplateArgumentListInfo *ExplicitTemplateArgs, 4480 Expr **Args, unsigned NumArgs, 4481 OverloadCandidateSet& CandidateSet, 4482 bool SuppressUserConversions) { 4483 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4484 return; 4485 4486 // C++ [over.match.funcs]p7: 4487 // In each case where a candidate is a function template, candidate 4488 // function template specializations are generated using template argument 4489 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4490 // candidate functions in the usual way.113) A given name can refer to one 4491 // or more function templates and also to a set of overloaded non-template 4492 // functions. In such a case, the candidate functions generated from each 4493 // function template are combined with the set of non-template candidate 4494 // functions. 4495 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4496 FunctionDecl *Specialization = 0; 4497 if (TemplateDeductionResult Result 4498 = DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs, 4499 Args, NumArgs, Specialization, Info)) { 4500 CandidateSet.push_back(OverloadCandidate()); 4501 OverloadCandidate &Candidate = CandidateSet.back(); 4502 Candidate.FoundDecl = FoundDecl; 4503 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4504 Candidate.Viable = false; 4505 Candidate.FailureKind = ovl_fail_bad_deduction; 4506 Candidate.IsSurrogate = false; 4507 Candidate.IgnoreObjectArgument = false; 4508 Candidate.ExplicitCallArguments = NumArgs; 4509 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4510 Info); 4511 return; 4512 } 4513 4514 // Add the function template specialization produced by template argument 4515 // deduction as a candidate. 4516 assert(Specialization && "Missing function template specialization?"); 4517 AddOverloadCandidate(Specialization, FoundDecl, Args, NumArgs, CandidateSet, 4518 SuppressUserConversions); 4519} 4520 4521/// AddConversionCandidate - Add a C++ conversion function as a 4522/// candidate in the candidate set (C++ [over.match.conv], 4523/// C++ [over.match.copy]). From is the expression we're converting from, 4524/// and ToType is the type that we're eventually trying to convert to 4525/// (which may or may not be the same type as the type that the 4526/// conversion function produces). 4527void 4528Sema::AddConversionCandidate(CXXConversionDecl *Conversion, 4529 DeclAccessPair FoundDecl, 4530 CXXRecordDecl *ActingContext, 4531 Expr *From, QualType ToType, 4532 OverloadCandidateSet& CandidateSet) { 4533 assert(!Conversion->getDescribedFunctionTemplate() && 4534 "Conversion function templates use AddTemplateConversionCandidate"); 4535 QualType ConvType = Conversion->getConversionType().getNonReferenceType(); 4536 if (!CandidateSet.isNewCandidate(Conversion)) 4537 return; 4538 4539 // Overload resolution is always an unevaluated context. 4540 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4541 4542 // Add this candidate 4543 CandidateSet.push_back(OverloadCandidate()); 4544 OverloadCandidate& Candidate = CandidateSet.back(); 4545 Candidate.FoundDecl = FoundDecl; 4546 Candidate.Function = Conversion; 4547 Candidate.IsSurrogate = false; 4548 Candidate.IgnoreObjectArgument = false; 4549 Candidate.FinalConversion.setAsIdentityConversion(); 4550 Candidate.FinalConversion.setFromType(ConvType); 4551 Candidate.FinalConversion.setAllToTypes(ToType); 4552 Candidate.Viable = true; 4553 Candidate.Conversions.resize(1); 4554 Candidate.ExplicitCallArguments = 1; 4555 4556 // C++ [over.match.funcs]p4: 4557 // For conversion functions, the function is considered to be a member of 4558 // the class of the implicit implied object argument for the purpose of 4559 // defining the type of the implicit object parameter. 4560 // 4561 // Determine the implicit conversion sequence for the implicit 4562 // object parameter. 4563 QualType ImplicitParamType = From->getType(); 4564 if (const PointerType *FromPtrType = ImplicitParamType->getAs<PointerType>()) 4565 ImplicitParamType = FromPtrType->getPointeeType(); 4566 CXXRecordDecl *ConversionContext 4567 = cast<CXXRecordDecl>(ImplicitParamType->getAs<RecordType>()->getDecl()); 4568 4569 Candidate.Conversions[0] 4570 = TryObjectArgumentInitialization(*this, From->getType(), 4571 From->Classify(Context), 4572 Conversion, ConversionContext); 4573 4574 if (Candidate.Conversions[0].isBad()) { 4575 Candidate.Viable = false; 4576 Candidate.FailureKind = ovl_fail_bad_conversion; 4577 return; 4578 } 4579 4580 // We won't go through a user-define type conversion function to convert a 4581 // derived to base as such conversions are given Conversion Rank. They only 4582 // go through a copy constructor. 13.3.3.1.2-p4 [over.ics.user] 4583 QualType FromCanon 4584 = Context.getCanonicalType(From->getType().getUnqualifiedType()); 4585 QualType ToCanon = Context.getCanonicalType(ToType).getUnqualifiedType(); 4586 if (FromCanon == ToCanon || IsDerivedFrom(FromCanon, ToCanon)) { 4587 Candidate.Viable = false; 4588 Candidate.FailureKind = ovl_fail_trivial_conversion; 4589 return; 4590 } 4591 4592 // To determine what the conversion from the result of calling the 4593 // conversion function to the type we're eventually trying to 4594 // convert to (ToType), we need to synthesize a call to the 4595 // conversion function and attempt copy initialization from it. This 4596 // makes sure that we get the right semantics with respect to 4597 // lvalues/rvalues and the type. Fortunately, we can allocate this 4598 // call on the stack and we don't need its arguments to be 4599 // well-formed. 4600 DeclRefExpr ConversionRef(Conversion, Conversion->getType(), 4601 VK_LValue, From->getLocStart()); 4602 ImplicitCastExpr ConversionFn(ImplicitCastExpr::OnStack, 4603 Context.getPointerType(Conversion->getType()), 4604 CK_FunctionToPointerDecay, 4605 &ConversionRef, VK_RValue); 4606 4607 QualType ConversionType = Conversion->getConversionType(); 4608 if (RequireCompleteType(From->getLocStart(), ConversionType, 0)) { 4609 Candidate.Viable = false; 4610 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4611 return; 4612 } 4613 4614 ExprValueKind VK = Expr::getValueKindForType(ConversionType); 4615 4616 // Note that it is safe to allocate CallExpr on the stack here because 4617 // there are 0 arguments (i.e., nothing is allocated using ASTContext's 4618 // allocator). 4619 QualType CallResultType = ConversionType.getNonLValueExprType(Context); 4620 CallExpr Call(Context, &ConversionFn, 0, 0, CallResultType, VK, 4621 From->getLocStart()); 4622 ImplicitConversionSequence ICS = 4623 TryCopyInitialization(*this, &Call, ToType, 4624 /*SuppressUserConversions=*/true, 4625 /*InOverloadResolution=*/false, 4626 /*AllowObjCWritebackConversion=*/false); 4627 4628 switch (ICS.getKind()) { 4629 case ImplicitConversionSequence::StandardConversion: 4630 Candidate.FinalConversion = ICS.Standard; 4631 4632 // C++ [over.ics.user]p3: 4633 // If the user-defined conversion is specified by a specialization of a 4634 // conversion function template, the second standard conversion sequence 4635 // shall have exact match rank. 4636 if (Conversion->getPrimaryTemplate() && 4637 GetConversionRank(ICS.Standard.Second) != ICR_Exact_Match) { 4638 Candidate.Viable = false; 4639 Candidate.FailureKind = ovl_fail_final_conversion_not_exact; 4640 } 4641 4642 // C++0x [dcl.init.ref]p5: 4643 // In the second case, if the reference is an rvalue reference and 4644 // the second standard conversion sequence of the user-defined 4645 // conversion sequence includes an lvalue-to-rvalue conversion, the 4646 // program is ill-formed. 4647 if (ToType->isRValueReferenceType() && 4648 ICS.Standard.First == ICK_Lvalue_To_Rvalue) { 4649 Candidate.Viable = false; 4650 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4651 } 4652 break; 4653 4654 case ImplicitConversionSequence::BadConversion: 4655 Candidate.Viable = false; 4656 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4657 break; 4658 4659 default: 4660 llvm_unreachable( 4661 "Can only end up with a standard conversion sequence or failure"); 4662 } 4663} 4664 4665/// \brief Adds a conversion function template specialization 4666/// candidate to the overload set, using template argument deduction 4667/// to deduce the template arguments of the conversion function 4668/// template from the type that we are converting to (C++ 4669/// [temp.deduct.conv]). 4670void 4671Sema::AddTemplateConversionCandidate(FunctionTemplateDecl *FunctionTemplate, 4672 DeclAccessPair FoundDecl, 4673 CXXRecordDecl *ActingDC, 4674 Expr *From, QualType ToType, 4675 OverloadCandidateSet &CandidateSet) { 4676 assert(isa<CXXConversionDecl>(FunctionTemplate->getTemplatedDecl()) && 4677 "Only conversion function templates permitted here"); 4678 4679 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4680 return; 4681 4682 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4683 CXXConversionDecl *Specialization = 0; 4684 if (TemplateDeductionResult Result 4685 = DeduceTemplateArguments(FunctionTemplate, ToType, 4686 Specialization, Info)) { 4687 CandidateSet.push_back(OverloadCandidate()); 4688 OverloadCandidate &Candidate = CandidateSet.back(); 4689 Candidate.FoundDecl = FoundDecl; 4690 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4691 Candidate.Viable = false; 4692 Candidate.FailureKind = ovl_fail_bad_deduction; 4693 Candidate.IsSurrogate = false; 4694 Candidate.IgnoreObjectArgument = false; 4695 Candidate.ExplicitCallArguments = 1; 4696 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4697 Info); 4698 return; 4699 } 4700 4701 // Add the conversion function template specialization produced by 4702 // template argument deduction as a candidate. 4703 assert(Specialization && "Missing function template specialization?"); 4704 AddConversionCandidate(Specialization, FoundDecl, ActingDC, From, ToType, 4705 CandidateSet); 4706} 4707 4708/// AddSurrogateCandidate - Adds a "surrogate" candidate function that 4709/// converts the given @c Object to a function pointer via the 4710/// conversion function @c Conversion, and then attempts to call it 4711/// with the given arguments (C++ [over.call.object]p2-4). Proto is 4712/// the type of function that we'll eventually be calling. 4713void Sema::AddSurrogateCandidate(CXXConversionDecl *Conversion, 4714 DeclAccessPair FoundDecl, 4715 CXXRecordDecl *ActingContext, 4716 const FunctionProtoType *Proto, 4717 Expr *Object, 4718 Expr **Args, unsigned NumArgs, 4719 OverloadCandidateSet& CandidateSet) { 4720 if (!CandidateSet.isNewCandidate(Conversion)) 4721 return; 4722 4723 // Overload resolution is always an unevaluated context. 4724 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4725 4726 CandidateSet.push_back(OverloadCandidate()); 4727 OverloadCandidate& Candidate = CandidateSet.back(); 4728 Candidate.FoundDecl = FoundDecl; 4729 Candidate.Function = 0; 4730 Candidate.Surrogate = Conversion; 4731 Candidate.Viable = true; 4732 Candidate.IsSurrogate = true; 4733 Candidate.IgnoreObjectArgument = false; 4734 Candidate.Conversions.resize(NumArgs + 1); 4735 Candidate.ExplicitCallArguments = NumArgs; 4736 4737 // Determine the implicit conversion sequence for the implicit 4738 // object parameter. 4739 ImplicitConversionSequence ObjectInit 4740 = TryObjectArgumentInitialization(*this, Object->getType(), 4741 Object->Classify(Context), 4742 Conversion, ActingContext); 4743 if (ObjectInit.isBad()) { 4744 Candidate.Viable = false; 4745 Candidate.FailureKind = ovl_fail_bad_conversion; 4746 Candidate.Conversions[0] = ObjectInit; 4747 return; 4748 } 4749 4750 // The first conversion is actually a user-defined conversion whose 4751 // first conversion is ObjectInit's standard conversion (which is 4752 // effectively a reference binding). Record it as such. 4753 Candidate.Conversions[0].setUserDefined(); 4754 Candidate.Conversions[0].UserDefined.Before = ObjectInit.Standard; 4755 Candidate.Conversions[0].UserDefined.EllipsisConversion = false; 4756 Candidate.Conversions[0].UserDefined.ConversionFunction = Conversion; 4757 Candidate.Conversions[0].UserDefined.FoundConversionFunction = FoundDecl; 4758 Candidate.Conversions[0].UserDefined.After 4759 = Candidate.Conversions[0].UserDefined.Before; 4760 Candidate.Conversions[0].UserDefined.After.setAsIdentityConversion(); 4761 4762 // Find the 4763 unsigned NumArgsInProto = Proto->getNumArgs(); 4764 4765 // (C++ 13.3.2p2): A candidate function having fewer than m 4766 // parameters is viable only if it has an ellipsis in its parameter 4767 // list (8.3.5). 4768 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4769 Candidate.Viable = false; 4770 Candidate.FailureKind = ovl_fail_too_many_arguments; 4771 return; 4772 } 4773 4774 // Function types don't have any default arguments, so just check if 4775 // we have enough arguments. 4776 if (NumArgs < NumArgsInProto) { 4777 // Not enough arguments. 4778 Candidate.Viable = false; 4779 Candidate.FailureKind = ovl_fail_too_few_arguments; 4780 return; 4781 } 4782 4783 // Determine the implicit conversion sequences for each of the 4784 // arguments. 4785 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4786 if (ArgIdx < NumArgsInProto) { 4787 // (C++ 13.3.2p3): for F to be a viable function, there shall 4788 // exist for each argument an implicit conversion sequence 4789 // (13.3.3.1) that converts that argument to the corresponding 4790 // parameter of F. 4791 QualType ParamType = Proto->getArgType(ArgIdx); 4792 Candidate.Conversions[ArgIdx + 1] 4793 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4794 /*SuppressUserConversions=*/false, 4795 /*InOverloadResolution=*/false, 4796 /*AllowObjCWritebackConversion=*/ 4797 getLangOptions().ObjCAutoRefCount); 4798 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4799 Candidate.Viable = false; 4800 Candidate.FailureKind = ovl_fail_bad_conversion; 4801 break; 4802 } 4803 } else { 4804 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4805 // argument for which there is no corresponding parameter is 4806 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4807 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4808 } 4809 } 4810} 4811 4812/// \brief Add overload candidates for overloaded operators that are 4813/// member functions. 4814/// 4815/// Add the overloaded operator candidates that are member functions 4816/// for the operator Op that was used in an operator expression such 4817/// as "x Op y". , Args/NumArgs provides the operator arguments, and 4818/// CandidateSet will store the added overload candidates. (C++ 4819/// [over.match.oper]). 4820void Sema::AddMemberOperatorCandidates(OverloadedOperatorKind Op, 4821 SourceLocation OpLoc, 4822 Expr **Args, unsigned NumArgs, 4823 OverloadCandidateSet& CandidateSet, 4824 SourceRange OpRange) { 4825 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 4826 4827 // C++ [over.match.oper]p3: 4828 // For a unary operator @ with an operand of a type whose 4829 // cv-unqualified version is T1, and for a binary operator @ with 4830 // a left operand of a type whose cv-unqualified version is T1 and 4831 // a right operand of a type whose cv-unqualified version is T2, 4832 // three sets of candidate functions, designated member 4833 // candidates, non-member candidates and built-in candidates, are 4834 // constructed as follows: 4835 QualType T1 = Args[0]->getType(); 4836 4837 // -- If T1 is a class type, the set of member candidates is the 4838 // result of the qualified lookup of T1::operator@ 4839 // (13.3.1.1.1); otherwise, the set of member candidates is 4840 // empty. 4841 if (const RecordType *T1Rec = T1->getAs<RecordType>()) { 4842 // Complete the type if it can be completed. Otherwise, we're done. 4843 if (RequireCompleteType(OpLoc, T1, PDiag())) 4844 return; 4845 4846 LookupResult Operators(*this, OpName, OpLoc, LookupOrdinaryName); 4847 LookupQualifiedName(Operators, T1Rec->getDecl()); 4848 Operators.suppressDiagnostics(); 4849 4850 for (LookupResult::iterator Oper = Operators.begin(), 4851 OperEnd = Operators.end(); 4852 Oper != OperEnd; 4853 ++Oper) 4854 AddMethodCandidate(Oper.getPair(), Args[0]->getType(), 4855 Args[0]->Classify(Context), Args + 1, NumArgs - 1, 4856 CandidateSet, 4857 /* SuppressUserConversions = */ false); 4858 } 4859} 4860 4861/// AddBuiltinCandidate - Add a candidate for a built-in 4862/// operator. ResultTy and ParamTys are the result and parameter types 4863/// of the built-in candidate, respectively. Args and NumArgs are the 4864/// arguments being passed to the candidate. IsAssignmentOperator 4865/// should be true when this built-in candidate is an assignment 4866/// operator. NumContextualBoolArguments is the number of arguments 4867/// (at the beginning of the argument list) that will be contextually 4868/// converted to bool. 4869void Sema::AddBuiltinCandidate(QualType ResultTy, QualType *ParamTys, 4870 Expr **Args, unsigned NumArgs, 4871 OverloadCandidateSet& CandidateSet, 4872 bool IsAssignmentOperator, 4873 unsigned NumContextualBoolArguments) { 4874 // Overload resolution is always an unevaluated context. 4875 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4876 4877 // Add this candidate 4878 CandidateSet.push_back(OverloadCandidate()); 4879 OverloadCandidate& Candidate = CandidateSet.back(); 4880 Candidate.FoundDecl = DeclAccessPair::make(0, AS_none); 4881 Candidate.Function = 0; 4882 Candidate.IsSurrogate = false; 4883 Candidate.IgnoreObjectArgument = false; 4884 Candidate.BuiltinTypes.ResultTy = ResultTy; 4885 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 4886 Candidate.BuiltinTypes.ParamTypes[ArgIdx] = ParamTys[ArgIdx]; 4887 4888 // Determine the implicit conversion sequences for each of the 4889 // arguments. 4890 Candidate.Viable = true; 4891 Candidate.Conversions.resize(NumArgs); 4892 Candidate.ExplicitCallArguments = NumArgs; 4893 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4894 // C++ [over.match.oper]p4: 4895 // For the built-in assignment operators, conversions of the 4896 // left operand are restricted as follows: 4897 // -- no temporaries are introduced to hold the left operand, and 4898 // -- no user-defined conversions are applied to the left 4899 // operand to achieve a type match with the left-most 4900 // parameter of a built-in candidate. 4901 // 4902 // We block these conversions by turning off user-defined 4903 // conversions, since that is the only way that initialization of 4904 // a reference to a non-class type can occur from something that 4905 // is not of the same type. 4906 if (ArgIdx < NumContextualBoolArguments) { 4907 assert(ParamTys[ArgIdx] == Context.BoolTy && 4908 "Contextual conversion to bool requires bool type"); 4909 Candidate.Conversions[ArgIdx] 4910 = TryContextuallyConvertToBool(*this, Args[ArgIdx]); 4911 } else { 4912 Candidate.Conversions[ArgIdx] 4913 = TryCopyInitialization(*this, Args[ArgIdx], ParamTys[ArgIdx], 4914 ArgIdx == 0 && IsAssignmentOperator, 4915 /*InOverloadResolution=*/false, 4916 /*AllowObjCWritebackConversion=*/ 4917 getLangOptions().ObjCAutoRefCount); 4918 } 4919 if (Candidate.Conversions[ArgIdx].isBad()) { 4920 Candidate.Viable = false; 4921 Candidate.FailureKind = ovl_fail_bad_conversion; 4922 break; 4923 } 4924 } 4925} 4926 4927/// BuiltinCandidateTypeSet - A set of types that will be used for the 4928/// candidate operator functions for built-in operators (C++ 4929/// [over.built]). The types are separated into pointer types and 4930/// enumeration types. 4931class BuiltinCandidateTypeSet { 4932 /// TypeSet - A set of types. 4933 typedef llvm::SmallPtrSet<QualType, 8> TypeSet; 4934 4935 /// PointerTypes - The set of pointer types that will be used in the 4936 /// built-in candidates. 4937 TypeSet PointerTypes; 4938 4939 /// MemberPointerTypes - The set of member pointer types that will be 4940 /// used in the built-in candidates. 4941 TypeSet MemberPointerTypes; 4942 4943 /// EnumerationTypes - The set of enumeration types that will be 4944 /// used in the built-in candidates. 4945 TypeSet EnumerationTypes; 4946 4947 /// \brief The set of vector types that will be used in the built-in 4948 /// candidates. 4949 TypeSet VectorTypes; 4950 4951 /// \brief A flag indicating non-record types are viable candidates 4952 bool HasNonRecordTypes; 4953 4954 /// \brief A flag indicating whether either arithmetic or enumeration types 4955 /// were present in the candidate set. 4956 bool HasArithmeticOrEnumeralTypes; 4957 4958 /// \brief A flag indicating whether the nullptr type was present in the 4959 /// candidate set. 4960 bool HasNullPtrType; 4961 4962 /// Sema - The semantic analysis instance where we are building the 4963 /// candidate type set. 4964 Sema &SemaRef; 4965 4966 /// Context - The AST context in which we will build the type sets. 4967 ASTContext &Context; 4968 4969 bool AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 4970 const Qualifiers &VisibleQuals); 4971 bool AddMemberPointerWithMoreQualifiedTypeVariants(QualType Ty); 4972 4973public: 4974 /// iterator - Iterates through the types that are part of the set. 4975 typedef TypeSet::iterator iterator; 4976 4977 BuiltinCandidateTypeSet(Sema &SemaRef) 4978 : HasNonRecordTypes(false), 4979 HasArithmeticOrEnumeralTypes(false), 4980 HasNullPtrType(false), 4981 SemaRef(SemaRef), 4982 Context(SemaRef.Context) { } 4983 4984 void AddTypesConvertedFrom(QualType Ty, 4985 SourceLocation Loc, 4986 bool AllowUserConversions, 4987 bool AllowExplicitConversions, 4988 const Qualifiers &VisibleTypeConversionsQuals); 4989 4990 /// pointer_begin - First pointer type found; 4991 iterator pointer_begin() { return PointerTypes.begin(); } 4992 4993 /// pointer_end - Past the last pointer type found; 4994 iterator pointer_end() { return PointerTypes.end(); } 4995 4996 /// member_pointer_begin - First member pointer type found; 4997 iterator member_pointer_begin() { return MemberPointerTypes.begin(); } 4998 4999 /// member_pointer_end - Past the last member pointer type found; 5000 iterator member_pointer_end() { return MemberPointerTypes.end(); } 5001 5002 /// enumeration_begin - First enumeration type found; 5003 iterator enumeration_begin() { return EnumerationTypes.begin(); } 5004 5005 /// enumeration_end - Past the last enumeration type found; 5006 iterator enumeration_end() { return EnumerationTypes.end(); } 5007 5008 iterator vector_begin() { return VectorTypes.begin(); } 5009 iterator vector_end() { return VectorTypes.end(); } 5010 5011 bool hasNonRecordTypes() { return HasNonRecordTypes; } 5012 bool hasArithmeticOrEnumeralTypes() { return HasArithmeticOrEnumeralTypes; } 5013 bool hasNullPtrType() const { return HasNullPtrType; } 5014}; 5015 5016/// AddPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty to 5017/// the set of pointer types along with any more-qualified variants of 5018/// that type. For example, if @p Ty is "int const *", this routine 5019/// will add "int const *", "int const volatile *", "int const 5020/// restrict *", and "int const volatile restrict *" to the set of 5021/// pointer types. Returns true if the add of @p Ty itself succeeded, 5022/// false otherwise. 5023/// 5024/// FIXME: what to do about extended qualifiers? 5025bool 5026BuiltinCandidateTypeSet::AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 5027 const Qualifiers &VisibleQuals) { 5028 5029 // Insert this type. 5030 if (!PointerTypes.insert(Ty)) 5031 return false; 5032 5033 QualType PointeeTy; 5034 const PointerType *PointerTy = Ty->getAs<PointerType>(); 5035 bool buildObjCPtr = false; 5036 if (!PointerTy) { 5037 if (const ObjCObjectPointerType *PTy = Ty->getAs<ObjCObjectPointerType>()) { 5038 PointeeTy = PTy->getPointeeType(); 5039 buildObjCPtr = true; 5040 } 5041 else 5042 llvm_unreachable("type was not a pointer type!"); 5043 } 5044 else 5045 PointeeTy = PointerTy->getPointeeType(); 5046 5047 // Don't add qualified variants of arrays. For one, they're not allowed 5048 // (the qualifier would sink to the element type), and for another, the 5049 // only overload situation where it matters is subscript or pointer +- int, 5050 // and those shouldn't have qualifier variants anyway. 5051 if (PointeeTy->isArrayType()) 5052 return true; 5053 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 5054 if (const ConstantArrayType *Array =Context.getAsConstantArrayType(PointeeTy)) 5055 BaseCVR = Array->getElementType().getCVRQualifiers(); 5056 bool hasVolatile = VisibleQuals.hasVolatile(); 5057 bool hasRestrict = VisibleQuals.hasRestrict(); 5058 5059 // Iterate through all strict supersets of BaseCVR. 5060 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 5061 if ((CVR | BaseCVR) != CVR) continue; 5062 // Skip over Volatile/Restrict if no Volatile/Restrict found anywhere 5063 // in the types. 5064 if ((CVR & Qualifiers::Volatile) && !hasVolatile) continue; 5065 if ((CVR & Qualifiers::Restrict) && !hasRestrict) continue; 5066 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 5067 if (!buildObjCPtr) 5068 PointerTypes.insert(Context.getPointerType(QPointeeTy)); 5069 else 5070 PointerTypes.insert(Context.getObjCObjectPointerType(QPointeeTy)); 5071 } 5072 5073 return true; 5074} 5075 5076/// AddMemberPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty 5077/// to the set of pointer types along with any more-qualified variants of 5078/// that type. For example, if @p Ty is "int const *", this routine 5079/// will add "int const *", "int const volatile *", "int const 5080/// restrict *", and "int const volatile restrict *" to the set of 5081/// pointer types. Returns true if the add of @p Ty itself succeeded, 5082/// false otherwise. 5083/// 5084/// FIXME: what to do about extended qualifiers? 5085bool 5086BuiltinCandidateTypeSet::AddMemberPointerWithMoreQualifiedTypeVariants( 5087 QualType Ty) { 5088 // Insert this type. 5089 if (!MemberPointerTypes.insert(Ty)) 5090 return false; 5091 5092 const MemberPointerType *PointerTy = Ty->getAs<MemberPointerType>(); 5093 assert(PointerTy && "type was not a member pointer type!"); 5094 5095 QualType PointeeTy = PointerTy->getPointeeType(); 5096 // Don't add qualified variants of arrays. For one, they're not allowed 5097 // (the qualifier would sink to the element type), and for another, the 5098 // only overload situation where it matters is subscript or pointer +- int, 5099 // and those shouldn't have qualifier variants anyway. 5100 if (PointeeTy->isArrayType()) 5101 return true; 5102 const Type *ClassTy = PointerTy->getClass(); 5103 5104 // Iterate through all strict supersets of the pointee type's CVR 5105 // qualifiers. 5106 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 5107 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 5108 if ((CVR | BaseCVR) != CVR) continue; 5109 5110 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 5111 MemberPointerTypes.insert( 5112 Context.getMemberPointerType(QPointeeTy, ClassTy)); 5113 } 5114 5115 return true; 5116} 5117 5118/// AddTypesConvertedFrom - Add each of the types to which the type @p 5119/// Ty can be implicit converted to the given set of @p Types. We're 5120/// primarily interested in pointer types and enumeration types. We also 5121/// take member pointer types, for the conditional operator. 5122/// AllowUserConversions is true if we should look at the conversion 5123/// functions of a class type, and AllowExplicitConversions if we 5124/// should also include the explicit conversion functions of a class 5125/// type. 5126void 5127BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty, 5128 SourceLocation Loc, 5129 bool AllowUserConversions, 5130 bool AllowExplicitConversions, 5131 const Qualifiers &VisibleQuals) { 5132 // Only deal with canonical types. 5133 Ty = Context.getCanonicalType(Ty); 5134 5135 // Look through reference types; they aren't part of the type of an 5136 // expression for the purposes of conversions. 5137 if (const ReferenceType *RefTy = Ty->getAs<ReferenceType>()) 5138 Ty = RefTy->getPointeeType(); 5139 5140 // If we're dealing with an array type, decay to the pointer. 5141 if (Ty->isArrayType()) 5142 Ty = SemaRef.Context.getArrayDecayedType(Ty); 5143 5144 // Otherwise, we don't care about qualifiers on the type. 5145 Ty = Ty.getLocalUnqualifiedType(); 5146 5147 // Flag if we ever add a non-record type. 5148 const RecordType *TyRec = Ty->getAs<RecordType>(); 5149 HasNonRecordTypes = HasNonRecordTypes || !TyRec; 5150 5151 // Flag if we encounter an arithmetic type. 5152 HasArithmeticOrEnumeralTypes = 5153 HasArithmeticOrEnumeralTypes || Ty->isArithmeticType(); 5154 5155 if (Ty->isObjCIdType() || Ty->isObjCClassType()) 5156 PointerTypes.insert(Ty); 5157 else if (Ty->getAs<PointerType>() || Ty->getAs<ObjCObjectPointerType>()) { 5158 // Insert our type, and its more-qualified variants, into the set 5159 // of types. 5160 if (!AddPointerWithMoreQualifiedTypeVariants(Ty, VisibleQuals)) 5161 return; 5162 } else if (Ty->isMemberPointerType()) { 5163 // Member pointers are far easier, since the pointee can't be converted. 5164 if (!AddMemberPointerWithMoreQualifiedTypeVariants(Ty)) 5165 return; 5166 } else if (Ty->isEnumeralType()) { 5167 HasArithmeticOrEnumeralTypes = true; 5168 EnumerationTypes.insert(Ty); 5169 } else if (Ty->isVectorType()) { 5170 // We treat vector types as arithmetic types in many contexts as an 5171 // extension. 5172 HasArithmeticOrEnumeralTypes = true; 5173 VectorTypes.insert(Ty); 5174 } else if (Ty->isNullPtrType()) { 5175 HasNullPtrType = true; 5176 } else if (AllowUserConversions && TyRec) { 5177 // No conversion functions in incomplete types. 5178 if (SemaRef.RequireCompleteType(Loc, Ty, 0)) 5179 return; 5180 5181 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 5182 const UnresolvedSetImpl *Conversions 5183 = ClassDecl->getVisibleConversionFunctions(); 5184 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 5185 E = Conversions->end(); I != E; ++I) { 5186 NamedDecl *D = I.getDecl(); 5187 if (isa<UsingShadowDecl>(D)) 5188 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 5189 5190 // Skip conversion function templates; they don't tell us anything 5191 // about which builtin types we can convert to. 5192 if (isa<FunctionTemplateDecl>(D)) 5193 continue; 5194 5195 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 5196 if (AllowExplicitConversions || !Conv->isExplicit()) { 5197 AddTypesConvertedFrom(Conv->getConversionType(), Loc, false, false, 5198 VisibleQuals); 5199 } 5200 } 5201 } 5202} 5203 5204/// \brief Helper function for AddBuiltinOperatorCandidates() that adds 5205/// the volatile- and non-volatile-qualified assignment operators for the 5206/// given type to the candidate set. 5207static void AddBuiltinAssignmentOperatorCandidates(Sema &S, 5208 QualType T, 5209 Expr **Args, 5210 unsigned NumArgs, 5211 OverloadCandidateSet &CandidateSet) { 5212 QualType ParamTypes[2]; 5213 5214 // T& operator=(T&, T) 5215 ParamTypes[0] = S.Context.getLValueReferenceType(T); 5216 ParamTypes[1] = T; 5217 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5218 /*IsAssignmentOperator=*/true); 5219 5220 if (!S.Context.getCanonicalType(T).isVolatileQualified()) { 5221 // volatile T& operator=(volatile T&, T) 5222 ParamTypes[0] 5223 = S.Context.getLValueReferenceType(S.Context.getVolatileType(T)); 5224 ParamTypes[1] = T; 5225 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5226 /*IsAssignmentOperator=*/true); 5227 } 5228} 5229 5230/// CollectVRQualifiers - This routine returns Volatile/Restrict qualifiers, 5231/// if any, found in visible type conversion functions found in ArgExpr's type. 5232static Qualifiers CollectVRQualifiers(ASTContext &Context, Expr* ArgExpr) { 5233 Qualifiers VRQuals; 5234 const RecordType *TyRec; 5235 if (const MemberPointerType *RHSMPType = 5236 ArgExpr->getType()->getAs<MemberPointerType>()) 5237 TyRec = RHSMPType->getClass()->getAs<RecordType>(); 5238 else 5239 TyRec = ArgExpr->getType()->getAs<RecordType>(); 5240 if (!TyRec) { 5241 // Just to be safe, assume the worst case. 5242 VRQuals.addVolatile(); 5243 VRQuals.addRestrict(); 5244 return VRQuals; 5245 } 5246 5247 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 5248 if (!ClassDecl->hasDefinition()) 5249 return VRQuals; 5250 5251 const UnresolvedSetImpl *Conversions = 5252 ClassDecl->getVisibleConversionFunctions(); 5253 5254 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 5255 E = Conversions->end(); I != E; ++I) { 5256 NamedDecl *D = I.getDecl(); 5257 if (isa<UsingShadowDecl>(D)) 5258 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 5259 if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(D)) { 5260 QualType CanTy = Context.getCanonicalType(Conv->getConversionType()); 5261 if (const ReferenceType *ResTypeRef = CanTy->getAs<ReferenceType>()) 5262 CanTy = ResTypeRef->getPointeeType(); 5263 // Need to go down the pointer/mempointer chain and add qualifiers 5264 // as see them. 5265 bool done = false; 5266 while (!done) { 5267 if (const PointerType *ResTypePtr = CanTy->getAs<PointerType>()) 5268 CanTy = ResTypePtr->getPointeeType(); 5269 else if (const MemberPointerType *ResTypeMPtr = 5270 CanTy->getAs<MemberPointerType>()) 5271 CanTy = ResTypeMPtr->getPointeeType(); 5272 else 5273 done = true; 5274 if (CanTy.isVolatileQualified()) 5275 VRQuals.addVolatile(); 5276 if (CanTy.isRestrictQualified()) 5277 VRQuals.addRestrict(); 5278 if (VRQuals.hasRestrict() && VRQuals.hasVolatile()) 5279 return VRQuals; 5280 } 5281 } 5282 } 5283 return VRQuals; 5284} 5285 5286namespace { 5287 5288/// \brief Helper class to manage the addition of builtin operator overload 5289/// candidates. It provides shared state and utility methods used throughout 5290/// the process, as well as a helper method to add each group of builtin 5291/// operator overloads from the standard to a candidate set. 5292class BuiltinOperatorOverloadBuilder { 5293 // Common instance state available to all overload candidate addition methods. 5294 Sema &S; 5295 Expr **Args; 5296 unsigned NumArgs; 5297 Qualifiers VisibleTypeConversionsQuals; 5298 bool HasArithmeticOrEnumeralCandidateType; 5299 SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes; 5300 OverloadCandidateSet &CandidateSet; 5301 5302 // Define some constants used to index and iterate over the arithemetic types 5303 // provided via the getArithmeticType() method below. 5304 // The "promoted arithmetic types" are the arithmetic 5305 // types are that preserved by promotion (C++ [over.built]p2). 5306 static const unsigned FirstIntegralType = 3; 5307 static const unsigned LastIntegralType = 18; 5308 static const unsigned FirstPromotedIntegralType = 3, 5309 LastPromotedIntegralType = 9; 5310 static const unsigned FirstPromotedArithmeticType = 0, 5311 LastPromotedArithmeticType = 9; 5312 static const unsigned NumArithmeticTypes = 18; 5313 5314 /// \brief Get the canonical type for a given arithmetic type index. 5315 CanQualType getArithmeticType(unsigned index) { 5316 assert(index < NumArithmeticTypes); 5317 static CanQualType ASTContext::* const 5318 ArithmeticTypes[NumArithmeticTypes] = { 5319 // Start of promoted types. 5320 &ASTContext::FloatTy, 5321 &ASTContext::DoubleTy, 5322 &ASTContext::LongDoubleTy, 5323 5324 // Start of integral types. 5325 &ASTContext::IntTy, 5326 &ASTContext::LongTy, 5327 &ASTContext::LongLongTy, 5328 &ASTContext::UnsignedIntTy, 5329 &ASTContext::UnsignedLongTy, 5330 &ASTContext::UnsignedLongLongTy, 5331 // End of promoted types. 5332 5333 &ASTContext::BoolTy, 5334 &ASTContext::CharTy, 5335 &ASTContext::WCharTy, 5336 &ASTContext::Char16Ty, 5337 &ASTContext::Char32Ty, 5338 &ASTContext::SignedCharTy, 5339 &ASTContext::ShortTy, 5340 &ASTContext::UnsignedCharTy, 5341 &ASTContext::UnsignedShortTy, 5342 // End of integral types. 5343 // FIXME: What about complex? 5344 }; 5345 return S.Context.*ArithmeticTypes[index]; 5346 } 5347 5348 /// \brief Gets the canonical type resulting from the usual arithemetic 5349 /// converions for the given arithmetic types. 5350 CanQualType getUsualArithmeticConversions(unsigned L, unsigned R) { 5351 // Accelerator table for performing the usual arithmetic conversions. 5352 // The rules are basically: 5353 // - if either is floating-point, use the wider floating-point 5354 // - if same signedness, use the higher rank 5355 // - if same size, use unsigned of the higher rank 5356 // - use the larger type 5357 // These rules, together with the axiom that higher ranks are 5358 // never smaller, are sufficient to precompute all of these results 5359 // *except* when dealing with signed types of higher rank. 5360 // (we could precompute SLL x UI for all known platforms, but it's 5361 // better not to make any assumptions). 5362 enum PromotedType { 5363 Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL, Dep=-1 5364 }; 5365 static PromotedType ConversionsTable[LastPromotedArithmeticType] 5366 [LastPromotedArithmeticType] = { 5367 /* Flt*/ { Flt, Dbl, LDbl, Flt, Flt, Flt, Flt, Flt, Flt }, 5368 /* Dbl*/ { Dbl, Dbl, LDbl, Dbl, Dbl, Dbl, Dbl, Dbl, Dbl }, 5369 /*LDbl*/ { LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl }, 5370 /* SI*/ { Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL }, 5371 /* SL*/ { Flt, Dbl, LDbl, SL, SL, SLL, Dep, UL, ULL }, 5372 /* SLL*/ { Flt, Dbl, LDbl, SLL, SLL, SLL, Dep, Dep, ULL }, 5373 /* UI*/ { Flt, Dbl, LDbl, UI, Dep, Dep, UI, UL, ULL }, 5374 /* UL*/ { Flt, Dbl, LDbl, UL, UL, Dep, UL, UL, ULL }, 5375 /* ULL*/ { Flt, Dbl, LDbl, ULL, ULL, ULL, ULL, ULL, ULL }, 5376 }; 5377 5378 assert(L < LastPromotedArithmeticType); 5379 assert(R < LastPromotedArithmeticType); 5380 int Idx = ConversionsTable[L][R]; 5381 5382 // Fast path: the table gives us a concrete answer. 5383 if (Idx != Dep) return getArithmeticType(Idx); 5384 5385 // Slow path: we need to compare widths. 5386 // An invariant is that the signed type has higher rank. 5387 CanQualType LT = getArithmeticType(L), 5388 RT = getArithmeticType(R); 5389 unsigned LW = S.Context.getIntWidth(LT), 5390 RW = S.Context.getIntWidth(RT); 5391 5392 // If they're different widths, use the signed type. 5393 if (LW > RW) return LT; 5394 else if (LW < RW) return RT; 5395 5396 // Otherwise, use the unsigned type of the signed type's rank. 5397 if (L == SL || R == SL) return S.Context.UnsignedLongTy; 5398 assert(L == SLL || R == SLL); 5399 return S.Context.UnsignedLongLongTy; 5400 } 5401 5402 /// \brief Helper method to factor out the common pattern of adding overloads 5403 /// for '++' and '--' builtin operators. 5404 void addPlusPlusMinusMinusStyleOverloads(QualType CandidateTy, 5405 bool HasVolatile) { 5406 QualType ParamTypes[2] = { 5407 S.Context.getLValueReferenceType(CandidateTy), 5408 S.Context.IntTy 5409 }; 5410 5411 // Non-volatile version. 5412 if (NumArgs == 1) 5413 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5414 else 5415 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5416 5417 // Use a heuristic to reduce number of builtin candidates in the set: 5418 // add volatile version only if there are conversions to a volatile type. 5419 if (HasVolatile) { 5420 ParamTypes[0] = 5421 S.Context.getLValueReferenceType( 5422 S.Context.getVolatileType(CandidateTy)); 5423 if (NumArgs == 1) 5424 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5425 else 5426 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5427 } 5428 } 5429 5430public: 5431 BuiltinOperatorOverloadBuilder( 5432 Sema &S, Expr **Args, unsigned NumArgs, 5433 Qualifiers VisibleTypeConversionsQuals, 5434 bool HasArithmeticOrEnumeralCandidateType, 5435 SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes, 5436 OverloadCandidateSet &CandidateSet) 5437 : S(S), Args(Args), NumArgs(NumArgs), 5438 VisibleTypeConversionsQuals(VisibleTypeConversionsQuals), 5439 HasArithmeticOrEnumeralCandidateType( 5440 HasArithmeticOrEnumeralCandidateType), 5441 CandidateTypes(CandidateTypes), 5442 CandidateSet(CandidateSet) { 5443 // Validate some of our static helper constants in debug builds. 5444 assert(getArithmeticType(FirstPromotedIntegralType) == S.Context.IntTy && 5445 "Invalid first promoted integral type"); 5446 assert(getArithmeticType(LastPromotedIntegralType - 1) 5447 == S.Context.UnsignedLongLongTy && 5448 "Invalid last promoted integral type"); 5449 assert(getArithmeticType(FirstPromotedArithmeticType) 5450 == S.Context.FloatTy && 5451 "Invalid first promoted arithmetic type"); 5452 assert(getArithmeticType(LastPromotedArithmeticType - 1) 5453 == S.Context.UnsignedLongLongTy && 5454 "Invalid last promoted arithmetic type"); 5455 } 5456 5457 // C++ [over.built]p3: 5458 // 5459 // For every pair (T, VQ), where T is an arithmetic type, and VQ 5460 // is either volatile or empty, there exist candidate operator 5461 // functions of the form 5462 // 5463 // VQ T& operator++(VQ T&); 5464 // T operator++(VQ T&, int); 5465 // 5466 // C++ [over.built]p4: 5467 // 5468 // For every pair (T, VQ), where T is an arithmetic type other 5469 // than bool, and VQ is either volatile or empty, there exist 5470 // candidate operator functions of the form 5471 // 5472 // VQ T& operator--(VQ T&); 5473 // T operator--(VQ T&, int); 5474 void addPlusPlusMinusMinusArithmeticOverloads(OverloadedOperatorKind Op) { 5475 if (!HasArithmeticOrEnumeralCandidateType) 5476 return; 5477 5478 for (unsigned Arith = (Op == OO_PlusPlus? 0 : 1); 5479 Arith < NumArithmeticTypes; ++Arith) { 5480 addPlusPlusMinusMinusStyleOverloads( 5481 getArithmeticType(Arith), 5482 VisibleTypeConversionsQuals.hasVolatile()); 5483 } 5484 } 5485 5486 // C++ [over.built]p5: 5487 // 5488 // For every pair (T, VQ), where T is a cv-qualified or 5489 // cv-unqualified object type, and VQ is either volatile or 5490 // empty, there exist candidate operator functions of the form 5491 // 5492 // T*VQ& operator++(T*VQ&); 5493 // T*VQ& operator--(T*VQ&); 5494 // T* operator++(T*VQ&, int); 5495 // T* operator--(T*VQ&, int); 5496 void addPlusPlusMinusMinusPointerOverloads() { 5497 for (BuiltinCandidateTypeSet::iterator 5498 Ptr = CandidateTypes[0].pointer_begin(), 5499 PtrEnd = CandidateTypes[0].pointer_end(); 5500 Ptr != PtrEnd; ++Ptr) { 5501 // Skip pointer types that aren't pointers to object types. 5502 if (!(*Ptr)->getPointeeType()->isObjectType()) 5503 continue; 5504 5505 addPlusPlusMinusMinusStyleOverloads(*Ptr, 5506 (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5507 VisibleTypeConversionsQuals.hasVolatile())); 5508 } 5509 } 5510 5511 // C++ [over.built]p6: 5512 // For every cv-qualified or cv-unqualified object type T, there 5513 // exist candidate operator functions of the form 5514 // 5515 // T& operator*(T*); 5516 // 5517 // C++ [over.built]p7: 5518 // For every function type T that does not have cv-qualifiers or a 5519 // ref-qualifier, there exist candidate operator functions of the form 5520 // T& operator*(T*); 5521 void addUnaryStarPointerOverloads() { 5522 for (BuiltinCandidateTypeSet::iterator 5523 Ptr = CandidateTypes[0].pointer_begin(), 5524 PtrEnd = CandidateTypes[0].pointer_end(); 5525 Ptr != PtrEnd; ++Ptr) { 5526 QualType ParamTy = *Ptr; 5527 QualType PointeeTy = ParamTy->getPointeeType(); 5528 if (!PointeeTy->isObjectType() && !PointeeTy->isFunctionType()) 5529 continue; 5530 5531 if (const FunctionProtoType *Proto =PointeeTy->getAs<FunctionProtoType>()) 5532 if (Proto->getTypeQuals() || Proto->getRefQualifier()) 5533 continue; 5534 5535 S.AddBuiltinCandidate(S.Context.getLValueReferenceType(PointeeTy), 5536 &ParamTy, Args, 1, CandidateSet); 5537 } 5538 } 5539 5540 // C++ [over.built]p9: 5541 // For every promoted arithmetic type T, there exist candidate 5542 // operator functions of the form 5543 // 5544 // T operator+(T); 5545 // T operator-(T); 5546 void addUnaryPlusOrMinusArithmeticOverloads() { 5547 if (!HasArithmeticOrEnumeralCandidateType) 5548 return; 5549 5550 for (unsigned Arith = FirstPromotedArithmeticType; 5551 Arith < LastPromotedArithmeticType; ++Arith) { 5552 QualType ArithTy = getArithmeticType(Arith); 5553 S.AddBuiltinCandidate(ArithTy, &ArithTy, Args, 1, CandidateSet); 5554 } 5555 5556 // Extension: We also add these operators for vector types. 5557 for (BuiltinCandidateTypeSet::iterator 5558 Vec = CandidateTypes[0].vector_begin(), 5559 VecEnd = CandidateTypes[0].vector_end(); 5560 Vec != VecEnd; ++Vec) { 5561 QualType VecTy = *Vec; 5562 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5563 } 5564 } 5565 5566 // C++ [over.built]p8: 5567 // For every type T, there exist candidate operator functions of 5568 // the form 5569 // 5570 // T* operator+(T*); 5571 void addUnaryPlusPointerOverloads() { 5572 for (BuiltinCandidateTypeSet::iterator 5573 Ptr = CandidateTypes[0].pointer_begin(), 5574 PtrEnd = CandidateTypes[0].pointer_end(); 5575 Ptr != PtrEnd; ++Ptr) { 5576 QualType ParamTy = *Ptr; 5577 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet); 5578 } 5579 } 5580 5581 // C++ [over.built]p10: 5582 // For every promoted integral type T, there exist candidate 5583 // operator functions of the form 5584 // 5585 // T operator~(T); 5586 void addUnaryTildePromotedIntegralOverloads() { 5587 if (!HasArithmeticOrEnumeralCandidateType) 5588 return; 5589 5590 for (unsigned Int = FirstPromotedIntegralType; 5591 Int < LastPromotedIntegralType; ++Int) { 5592 QualType IntTy = getArithmeticType(Int); 5593 S.AddBuiltinCandidate(IntTy, &IntTy, Args, 1, CandidateSet); 5594 } 5595 5596 // Extension: We also add this operator for vector types. 5597 for (BuiltinCandidateTypeSet::iterator 5598 Vec = CandidateTypes[0].vector_begin(), 5599 VecEnd = CandidateTypes[0].vector_end(); 5600 Vec != VecEnd; ++Vec) { 5601 QualType VecTy = *Vec; 5602 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5603 } 5604 } 5605 5606 // C++ [over.match.oper]p16: 5607 // For every pointer to member type T, there exist candidate operator 5608 // functions of the form 5609 // 5610 // bool operator==(T,T); 5611 // bool operator!=(T,T); 5612 void addEqualEqualOrNotEqualMemberPointerOverloads() { 5613 /// Set of (canonical) types that we've already handled. 5614 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5615 5616 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5617 for (BuiltinCandidateTypeSet::iterator 5618 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5619 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5620 MemPtr != MemPtrEnd; 5621 ++MemPtr) { 5622 // Don't add the same builtin candidate twice. 5623 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5624 continue; 5625 5626 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 5627 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5628 CandidateSet); 5629 } 5630 } 5631 } 5632 5633 // C++ [over.built]p15: 5634 // 5635 // For every T, where T is an enumeration type, a pointer type, or 5636 // std::nullptr_t, there exist candidate operator functions of the form 5637 // 5638 // bool operator<(T, T); 5639 // bool operator>(T, T); 5640 // bool operator<=(T, T); 5641 // bool operator>=(T, T); 5642 // bool operator==(T, T); 5643 // bool operator!=(T, T); 5644 void addRelationalPointerOrEnumeralOverloads() { 5645 // C++ [over.built]p1: 5646 // If there is a user-written candidate with the same name and parameter 5647 // types as a built-in candidate operator function, the built-in operator 5648 // function is hidden and is not included in the set of candidate 5649 // functions. 5650 // 5651 // The text is actually in a note, but if we don't implement it then we end 5652 // up with ambiguities when the user provides an overloaded operator for 5653 // an enumeration type. Note that only enumeration types have this problem, 5654 // so we track which enumeration types we've seen operators for. Also, the 5655 // only other overloaded operator with enumeration argumenst, operator=, 5656 // cannot be overloaded for enumeration types, so this is the only place 5657 // where we must suppress candidates like this. 5658 llvm::DenseSet<std::pair<CanQualType, CanQualType> > 5659 UserDefinedBinaryOperators; 5660 5661 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5662 if (CandidateTypes[ArgIdx].enumeration_begin() != 5663 CandidateTypes[ArgIdx].enumeration_end()) { 5664 for (OverloadCandidateSet::iterator C = CandidateSet.begin(), 5665 CEnd = CandidateSet.end(); 5666 C != CEnd; ++C) { 5667 if (!C->Viable || !C->Function || C->Function->getNumParams() != 2) 5668 continue; 5669 5670 QualType FirstParamType = 5671 C->Function->getParamDecl(0)->getType().getUnqualifiedType(); 5672 QualType SecondParamType = 5673 C->Function->getParamDecl(1)->getType().getUnqualifiedType(); 5674 5675 // Skip if either parameter isn't of enumeral type. 5676 if (!FirstParamType->isEnumeralType() || 5677 !SecondParamType->isEnumeralType()) 5678 continue; 5679 5680 // Add this operator to the set of known user-defined operators. 5681 UserDefinedBinaryOperators.insert( 5682 std::make_pair(S.Context.getCanonicalType(FirstParamType), 5683 S.Context.getCanonicalType(SecondParamType))); 5684 } 5685 } 5686 } 5687 5688 /// Set of (canonical) types that we've already handled. 5689 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5690 5691 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5692 for (BuiltinCandidateTypeSet::iterator 5693 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 5694 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 5695 Ptr != PtrEnd; ++Ptr) { 5696 // Don't add the same builtin candidate twice. 5697 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5698 continue; 5699 5700 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5701 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5702 CandidateSet); 5703 } 5704 for (BuiltinCandidateTypeSet::iterator 5705 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5706 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5707 Enum != EnumEnd; ++Enum) { 5708 CanQualType CanonType = S.Context.getCanonicalType(*Enum); 5709 5710 // Don't add the same builtin candidate twice, or if a user defined 5711 // candidate exists. 5712 if (!AddedTypes.insert(CanonType) || 5713 UserDefinedBinaryOperators.count(std::make_pair(CanonType, 5714 CanonType))) 5715 continue; 5716 5717 QualType ParamTypes[2] = { *Enum, *Enum }; 5718 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5719 CandidateSet); 5720 } 5721 5722 if (CandidateTypes[ArgIdx].hasNullPtrType()) { 5723 CanQualType NullPtrTy = S.Context.getCanonicalType(S.Context.NullPtrTy); 5724 if (AddedTypes.insert(NullPtrTy) && 5725 !UserDefinedBinaryOperators.count(std::make_pair(NullPtrTy, 5726 NullPtrTy))) { 5727 QualType ParamTypes[2] = { NullPtrTy, NullPtrTy }; 5728 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5729 CandidateSet); 5730 } 5731 } 5732 } 5733 } 5734 5735 // C++ [over.built]p13: 5736 // 5737 // For every cv-qualified or cv-unqualified object type T 5738 // there exist candidate operator functions of the form 5739 // 5740 // T* operator+(T*, ptrdiff_t); 5741 // T& operator[](T*, ptrdiff_t); [BELOW] 5742 // T* operator-(T*, ptrdiff_t); 5743 // T* operator+(ptrdiff_t, T*); 5744 // T& operator[](ptrdiff_t, T*); [BELOW] 5745 // 5746 // C++ [over.built]p14: 5747 // 5748 // For every T, where T is a pointer to object type, there 5749 // exist candidate operator functions of the form 5750 // 5751 // ptrdiff_t operator-(T, T); 5752 void addBinaryPlusOrMinusPointerOverloads(OverloadedOperatorKind Op) { 5753 /// Set of (canonical) types that we've already handled. 5754 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5755 5756 for (int Arg = 0; Arg < 2; ++Arg) { 5757 QualType AsymetricParamTypes[2] = { 5758 S.Context.getPointerDiffType(), 5759 S.Context.getPointerDiffType(), 5760 }; 5761 for (BuiltinCandidateTypeSet::iterator 5762 Ptr = CandidateTypes[Arg].pointer_begin(), 5763 PtrEnd = CandidateTypes[Arg].pointer_end(); 5764 Ptr != PtrEnd; ++Ptr) { 5765 QualType PointeeTy = (*Ptr)->getPointeeType(); 5766 if (!PointeeTy->isObjectType()) 5767 continue; 5768 5769 AsymetricParamTypes[Arg] = *Ptr; 5770 if (Arg == 0 || Op == OO_Plus) { 5771 // operator+(T*, ptrdiff_t) or operator-(T*, ptrdiff_t) 5772 // T* operator+(ptrdiff_t, T*); 5773 S.AddBuiltinCandidate(*Ptr, AsymetricParamTypes, Args, 2, 5774 CandidateSet); 5775 } 5776 if (Op == OO_Minus) { 5777 // ptrdiff_t operator-(T, T); 5778 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5779 continue; 5780 5781 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5782 S.AddBuiltinCandidate(S.Context.getPointerDiffType(), ParamTypes, 5783 Args, 2, CandidateSet); 5784 } 5785 } 5786 } 5787 } 5788 5789 // C++ [over.built]p12: 5790 // 5791 // For every pair of promoted arithmetic types L and R, there 5792 // exist candidate operator functions of the form 5793 // 5794 // LR operator*(L, R); 5795 // LR operator/(L, R); 5796 // LR operator+(L, R); 5797 // LR operator-(L, R); 5798 // bool operator<(L, R); 5799 // bool operator>(L, R); 5800 // bool operator<=(L, R); 5801 // bool operator>=(L, R); 5802 // bool operator==(L, R); 5803 // bool operator!=(L, R); 5804 // 5805 // where LR is the result of the usual arithmetic conversions 5806 // between types L and R. 5807 // 5808 // C++ [over.built]p24: 5809 // 5810 // For every pair of promoted arithmetic types L and R, there exist 5811 // candidate operator functions of the form 5812 // 5813 // LR operator?(bool, L, R); 5814 // 5815 // where LR is the result of the usual arithmetic conversions 5816 // between types L and R. 5817 // Our candidates ignore the first parameter. 5818 void addGenericBinaryArithmeticOverloads(bool isComparison) { 5819 if (!HasArithmeticOrEnumeralCandidateType) 5820 return; 5821 5822 for (unsigned Left = FirstPromotedArithmeticType; 5823 Left < LastPromotedArithmeticType; ++Left) { 5824 for (unsigned Right = FirstPromotedArithmeticType; 5825 Right < LastPromotedArithmeticType; ++Right) { 5826 QualType LandR[2] = { getArithmeticType(Left), 5827 getArithmeticType(Right) }; 5828 QualType Result = 5829 isComparison ? S.Context.BoolTy 5830 : getUsualArithmeticConversions(Left, Right); 5831 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5832 } 5833 } 5834 5835 // Extension: Add the binary operators ==, !=, <, <=, >=, >, *, /, and the 5836 // conditional operator for vector types. 5837 for (BuiltinCandidateTypeSet::iterator 5838 Vec1 = CandidateTypes[0].vector_begin(), 5839 Vec1End = CandidateTypes[0].vector_end(); 5840 Vec1 != Vec1End; ++Vec1) { 5841 for (BuiltinCandidateTypeSet::iterator 5842 Vec2 = CandidateTypes[1].vector_begin(), 5843 Vec2End = CandidateTypes[1].vector_end(); 5844 Vec2 != Vec2End; ++Vec2) { 5845 QualType LandR[2] = { *Vec1, *Vec2 }; 5846 QualType Result = S.Context.BoolTy; 5847 if (!isComparison) { 5848 if ((*Vec1)->isExtVectorType() || !(*Vec2)->isExtVectorType()) 5849 Result = *Vec1; 5850 else 5851 Result = *Vec2; 5852 } 5853 5854 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5855 } 5856 } 5857 } 5858 5859 // C++ [over.built]p17: 5860 // 5861 // For every pair of promoted integral types L and R, there 5862 // exist candidate operator functions of the form 5863 // 5864 // LR operator%(L, R); 5865 // LR operator&(L, R); 5866 // LR operator^(L, R); 5867 // LR operator|(L, R); 5868 // L operator<<(L, R); 5869 // L operator>>(L, R); 5870 // 5871 // where LR is the result of the usual arithmetic conversions 5872 // between types L and R. 5873 void addBinaryBitwiseArithmeticOverloads(OverloadedOperatorKind Op) { 5874 if (!HasArithmeticOrEnumeralCandidateType) 5875 return; 5876 5877 for (unsigned Left = FirstPromotedIntegralType; 5878 Left < LastPromotedIntegralType; ++Left) { 5879 for (unsigned Right = FirstPromotedIntegralType; 5880 Right < LastPromotedIntegralType; ++Right) { 5881 QualType LandR[2] = { getArithmeticType(Left), 5882 getArithmeticType(Right) }; 5883 QualType Result = (Op == OO_LessLess || Op == OO_GreaterGreater) 5884 ? LandR[0] 5885 : getUsualArithmeticConversions(Left, Right); 5886 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5887 } 5888 } 5889 } 5890 5891 // C++ [over.built]p20: 5892 // 5893 // For every pair (T, VQ), where T is an enumeration or 5894 // pointer to member type and VQ is either volatile or 5895 // empty, there exist candidate operator functions of the form 5896 // 5897 // VQ T& operator=(VQ T&, T); 5898 void addAssignmentMemberPointerOrEnumeralOverloads() { 5899 /// Set of (canonical) types that we've already handled. 5900 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5901 5902 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 5903 for (BuiltinCandidateTypeSet::iterator 5904 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5905 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5906 Enum != EnumEnd; ++Enum) { 5907 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 5908 continue; 5909 5910 AddBuiltinAssignmentOperatorCandidates(S, *Enum, Args, 2, 5911 CandidateSet); 5912 } 5913 5914 for (BuiltinCandidateTypeSet::iterator 5915 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5916 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5917 MemPtr != MemPtrEnd; ++MemPtr) { 5918 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5919 continue; 5920 5921 AddBuiltinAssignmentOperatorCandidates(S, *MemPtr, Args, 2, 5922 CandidateSet); 5923 } 5924 } 5925 } 5926 5927 // C++ [over.built]p19: 5928 // 5929 // For every pair (T, VQ), where T is any type and VQ is either 5930 // volatile or empty, there exist candidate operator functions 5931 // of the form 5932 // 5933 // T*VQ& operator=(T*VQ&, T*); 5934 // 5935 // C++ [over.built]p21: 5936 // 5937 // For every pair (T, VQ), where T is a cv-qualified or 5938 // cv-unqualified object type and VQ is either volatile or 5939 // empty, there exist candidate operator functions of the form 5940 // 5941 // T*VQ& operator+=(T*VQ&, ptrdiff_t); 5942 // T*VQ& operator-=(T*VQ&, ptrdiff_t); 5943 void addAssignmentPointerOverloads(bool isEqualOp) { 5944 /// Set of (canonical) types that we've already handled. 5945 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5946 5947 for (BuiltinCandidateTypeSet::iterator 5948 Ptr = CandidateTypes[0].pointer_begin(), 5949 PtrEnd = CandidateTypes[0].pointer_end(); 5950 Ptr != PtrEnd; ++Ptr) { 5951 // If this is operator=, keep track of the builtin candidates we added. 5952 if (isEqualOp) 5953 AddedTypes.insert(S.Context.getCanonicalType(*Ptr)); 5954 else if (!(*Ptr)->getPointeeType()->isObjectType()) 5955 continue; 5956 5957 // non-volatile version 5958 QualType ParamTypes[2] = { 5959 S.Context.getLValueReferenceType(*Ptr), 5960 isEqualOp ? *Ptr : S.Context.getPointerDiffType(), 5961 }; 5962 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5963 /*IsAssigmentOperator=*/ isEqualOp); 5964 5965 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5966 VisibleTypeConversionsQuals.hasVolatile()) { 5967 // volatile version 5968 ParamTypes[0] = 5969 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 5970 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5971 /*IsAssigmentOperator=*/isEqualOp); 5972 } 5973 } 5974 5975 if (isEqualOp) { 5976 for (BuiltinCandidateTypeSet::iterator 5977 Ptr = CandidateTypes[1].pointer_begin(), 5978 PtrEnd = CandidateTypes[1].pointer_end(); 5979 Ptr != PtrEnd; ++Ptr) { 5980 // Make sure we don't add the same candidate twice. 5981 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5982 continue; 5983 5984 QualType ParamTypes[2] = { 5985 S.Context.getLValueReferenceType(*Ptr), 5986 *Ptr, 5987 }; 5988 5989 // non-volatile version 5990 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5991 /*IsAssigmentOperator=*/true); 5992 5993 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5994 VisibleTypeConversionsQuals.hasVolatile()) { 5995 // volatile version 5996 ParamTypes[0] = 5997 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 5998 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5999 CandidateSet, /*IsAssigmentOperator=*/true); 6000 } 6001 } 6002 } 6003 } 6004 6005 // C++ [over.built]p18: 6006 // 6007 // For every triple (L, VQ, R), where L is an arithmetic type, 6008 // VQ is either volatile or empty, and R is a promoted 6009 // arithmetic type, there exist candidate operator functions of 6010 // the form 6011 // 6012 // VQ L& operator=(VQ L&, R); 6013 // VQ L& operator*=(VQ L&, R); 6014 // VQ L& operator/=(VQ L&, R); 6015 // VQ L& operator+=(VQ L&, R); 6016 // VQ L& operator-=(VQ L&, R); 6017 void addAssignmentArithmeticOverloads(bool isEqualOp) { 6018 if (!HasArithmeticOrEnumeralCandidateType) 6019 return; 6020 6021 for (unsigned Left = 0; Left < NumArithmeticTypes; ++Left) { 6022 for (unsigned Right = FirstPromotedArithmeticType; 6023 Right < LastPromotedArithmeticType; ++Right) { 6024 QualType ParamTypes[2]; 6025 ParamTypes[1] = getArithmeticType(Right); 6026 6027 // Add this built-in operator as a candidate (VQ is empty). 6028 ParamTypes[0] = 6029 S.Context.getLValueReferenceType(getArithmeticType(Left)); 6030 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 6031 /*IsAssigmentOperator=*/isEqualOp); 6032 6033 // Add this built-in operator as a candidate (VQ is 'volatile'). 6034 if (VisibleTypeConversionsQuals.hasVolatile()) { 6035 ParamTypes[0] = 6036 S.Context.getVolatileType(getArithmeticType(Left)); 6037 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 6038 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 6039 CandidateSet, 6040 /*IsAssigmentOperator=*/isEqualOp); 6041 } 6042 } 6043 } 6044 6045 // Extension: Add the binary operators =, +=, -=, *=, /= for vector types. 6046 for (BuiltinCandidateTypeSet::iterator 6047 Vec1 = CandidateTypes[0].vector_begin(), 6048 Vec1End = CandidateTypes[0].vector_end(); 6049 Vec1 != Vec1End; ++Vec1) { 6050 for (BuiltinCandidateTypeSet::iterator 6051 Vec2 = CandidateTypes[1].vector_begin(), 6052 Vec2End = CandidateTypes[1].vector_end(); 6053 Vec2 != Vec2End; ++Vec2) { 6054 QualType ParamTypes[2]; 6055 ParamTypes[1] = *Vec2; 6056 // Add this built-in operator as a candidate (VQ is empty). 6057 ParamTypes[0] = S.Context.getLValueReferenceType(*Vec1); 6058 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 6059 /*IsAssigmentOperator=*/isEqualOp); 6060 6061 // Add this built-in operator as a candidate (VQ is 'volatile'). 6062 if (VisibleTypeConversionsQuals.hasVolatile()) { 6063 ParamTypes[0] = S.Context.getVolatileType(*Vec1); 6064 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 6065 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 6066 CandidateSet, 6067 /*IsAssigmentOperator=*/isEqualOp); 6068 } 6069 } 6070 } 6071 } 6072 6073 // C++ [over.built]p22: 6074 // 6075 // For every triple (L, VQ, R), where L is an integral type, VQ 6076 // is either volatile or empty, and R is a promoted integral 6077 // type, there exist candidate operator functions of the form 6078 // 6079 // VQ L& operator%=(VQ L&, R); 6080 // VQ L& operator<<=(VQ L&, R); 6081 // VQ L& operator>>=(VQ L&, R); 6082 // VQ L& operator&=(VQ L&, R); 6083 // VQ L& operator^=(VQ L&, R); 6084 // VQ L& operator|=(VQ L&, R); 6085 void addAssignmentIntegralOverloads() { 6086 if (!HasArithmeticOrEnumeralCandidateType) 6087 return; 6088 6089 for (unsigned Left = FirstIntegralType; Left < LastIntegralType; ++Left) { 6090 for (unsigned Right = FirstPromotedIntegralType; 6091 Right < LastPromotedIntegralType; ++Right) { 6092 QualType ParamTypes[2]; 6093 ParamTypes[1] = getArithmeticType(Right); 6094 6095 // Add this built-in operator as a candidate (VQ is empty). 6096 ParamTypes[0] = 6097 S.Context.getLValueReferenceType(getArithmeticType(Left)); 6098 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet); 6099 if (VisibleTypeConversionsQuals.hasVolatile()) { 6100 // Add this built-in operator as a candidate (VQ is 'volatile'). 6101 ParamTypes[0] = getArithmeticType(Left); 6102 ParamTypes[0] = S.Context.getVolatileType(ParamTypes[0]); 6103 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 6104 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 6105 CandidateSet); 6106 } 6107 } 6108 } 6109 } 6110 6111 // C++ [over.operator]p23: 6112 // 6113 // There also exist candidate operator functions of the form 6114 // 6115 // bool operator!(bool); 6116 // bool operator&&(bool, bool); 6117 // bool operator||(bool, bool); 6118 void addExclaimOverload() { 6119 QualType ParamTy = S.Context.BoolTy; 6120 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet, 6121 /*IsAssignmentOperator=*/false, 6122 /*NumContextualBoolArguments=*/1); 6123 } 6124 void addAmpAmpOrPipePipeOverload() { 6125 QualType ParamTypes[2] = { S.Context.BoolTy, S.Context.BoolTy }; 6126 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, CandidateSet, 6127 /*IsAssignmentOperator=*/false, 6128 /*NumContextualBoolArguments=*/2); 6129 } 6130 6131 // C++ [over.built]p13: 6132 // 6133 // For every cv-qualified or cv-unqualified object type T there 6134 // exist candidate operator functions of the form 6135 // 6136 // T* operator+(T*, ptrdiff_t); [ABOVE] 6137 // T& operator[](T*, ptrdiff_t); 6138 // T* operator-(T*, ptrdiff_t); [ABOVE] 6139 // T* operator+(ptrdiff_t, T*); [ABOVE] 6140 // T& operator[](ptrdiff_t, T*); 6141 void addSubscriptOverloads() { 6142 for (BuiltinCandidateTypeSet::iterator 6143 Ptr = CandidateTypes[0].pointer_begin(), 6144 PtrEnd = CandidateTypes[0].pointer_end(); 6145 Ptr != PtrEnd; ++Ptr) { 6146 QualType ParamTypes[2] = { *Ptr, S.Context.getPointerDiffType() }; 6147 QualType PointeeType = (*Ptr)->getPointeeType(); 6148 if (!PointeeType->isObjectType()) 6149 continue; 6150 6151 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 6152 6153 // T& operator[](T*, ptrdiff_t) 6154 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 6155 } 6156 6157 for (BuiltinCandidateTypeSet::iterator 6158 Ptr = CandidateTypes[1].pointer_begin(), 6159 PtrEnd = CandidateTypes[1].pointer_end(); 6160 Ptr != PtrEnd; ++Ptr) { 6161 QualType ParamTypes[2] = { S.Context.getPointerDiffType(), *Ptr }; 6162 QualType PointeeType = (*Ptr)->getPointeeType(); 6163 if (!PointeeType->isObjectType()) 6164 continue; 6165 6166 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 6167 6168 // T& operator[](ptrdiff_t, T*) 6169 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 6170 } 6171 } 6172 6173 // C++ [over.built]p11: 6174 // For every quintuple (C1, C2, T, CV1, CV2), where C2 is a class type, 6175 // C1 is the same type as C2 or is a derived class of C2, T is an object 6176 // type or a function type, and CV1 and CV2 are cv-qualifier-seqs, 6177 // there exist candidate operator functions of the form 6178 // 6179 // CV12 T& operator->*(CV1 C1*, CV2 T C2::*); 6180 // 6181 // where CV12 is the union of CV1 and CV2. 6182 void addArrowStarOverloads() { 6183 for (BuiltinCandidateTypeSet::iterator 6184 Ptr = CandidateTypes[0].pointer_begin(), 6185 PtrEnd = CandidateTypes[0].pointer_end(); 6186 Ptr != PtrEnd; ++Ptr) { 6187 QualType C1Ty = (*Ptr); 6188 QualType C1; 6189 QualifierCollector Q1; 6190 C1 = QualType(Q1.strip(C1Ty->getPointeeType()), 0); 6191 if (!isa<RecordType>(C1)) 6192 continue; 6193 // heuristic to reduce number of builtin candidates in the set. 6194 // Add volatile/restrict version only if there are conversions to a 6195 // volatile/restrict type. 6196 if (!VisibleTypeConversionsQuals.hasVolatile() && Q1.hasVolatile()) 6197 continue; 6198 if (!VisibleTypeConversionsQuals.hasRestrict() && Q1.hasRestrict()) 6199 continue; 6200 for (BuiltinCandidateTypeSet::iterator 6201 MemPtr = CandidateTypes[1].member_pointer_begin(), 6202 MemPtrEnd = CandidateTypes[1].member_pointer_end(); 6203 MemPtr != MemPtrEnd; ++MemPtr) { 6204 const MemberPointerType *mptr = cast<MemberPointerType>(*MemPtr); 6205 QualType C2 = QualType(mptr->getClass(), 0); 6206 C2 = C2.getUnqualifiedType(); 6207 if (C1 != C2 && !S.IsDerivedFrom(C1, C2)) 6208 break; 6209 QualType ParamTypes[2] = { *Ptr, *MemPtr }; 6210 // build CV12 T& 6211 QualType T = mptr->getPointeeType(); 6212 if (!VisibleTypeConversionsQuals.hasVolatile() && 6213 T.isVolatileQualified()) 6214 continue; 6215 if (!VisibleTypeConversionsQuals.hasRestrict() && 6216 T.isRestrictQualified()) 6217 continue; 6218 T = Q1.apply(S.Context, T); 6219 QualType ResultTy = S.Context.getLValueReferenceType(T); 6220 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 6221 } 6222 } 6223 } 6224 6225 // Note that we don't consider the first argument, since it has been 6226 // contextually converted to bool long ago. The candidates below are 6227 // therefore added as binary. 6228 // 6229 // C++ [over.built]p25: 6230 // For every type T, where T is a pointer, pointer-to-member, or scoped 6231 // enumeration type, there exist candidate operator functions of the form 6232 // 6233 // T operator?(bool, T, T); 6234 // 6235 void addConditionalOperatorOverloads() { 6236 /// Set of (canonical) types that we've already handled. 6237 llvm::SmallPtrSet<QualType, 8> AddedTypes; 6238 6239 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 6240 for (BuiltinCandidateTypeSet::iterator 6241 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 6242 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 6243 Ptr != PtrEnd; ++Ptr) { 6244 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 6245 continue; 6246 6247 QualType ParamTypes[2] = { *Ptr, *Ptr }; 6248 S.AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 6249 } 6250 6251 for (BuiltinCandidateTypeSet::iterator 6252 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 6253 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 6254 MemPtr != MemPtrEnd; ++MemPtr) { 6255 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 6256 continue; 6257 6258 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 6259 S.AddBuiltinCandidate(*MemPtr, ParamTypes, Args, 2, CandidateSet); 6260 } 6261 6262 if (S.getLangOptions().CPlusPlus0x) { 6263 for (BuiltinCandidateTypeSet::iterator 6264 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 6265 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 6266 Enum != EnumEnd; ++Enum) { 6267 if (!(*Enum)->getAs<EnumType>()->getDecl()->isScoped()) 6268 continue; 6269 6270 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 6271 continue; 6272 6273 QualType ParamTypes[2] = { *Enum, *Enum }; 6274 S.AddBuiltinCandidate(*Enum, ParamTypes, Args, 2, CandidateSet); 6275 } 6276 } 6277 } 6278 } 6279}; 6280 6281} // end anonymous namespace 6282 6283/// AddBuiltinOperatorCandidates - Add the appropriate built-in 6284/// operator overloads to the candidate set (C++ [over.built]), based 6285/// on the operator @p Op and the arguments given. For example, if the 6286/// operator is a binary '+', this routine might add "int 6287/// operator+(int, int)" to cover integer addition. 6288void 6289Sema::AddBuiltinOperatorCandidates(OverloadedOperatorKind Op, 6290 SourceLocation OpLoc, 6291 Expr **Args, unsigned NumArgs, 6292 OverloadCandidateSet& CandidateSet) { 6293 // Find all of the types that the arguments can convert to, but only 6294 // if the operator we're looking at has built-in operator candidates 6295 // that make use of these types. Also record whether we encounter non-record 6296 // candidate types or either arithmetic or enumeral candidate types. 6297 Qualifiers VisibleTypeConversionsQuals; 6298 VisibleTypeConversionsQuals.addConst(); 6299 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 6300 VisibleTypeConversionsQuals += CollectVRQualifiers(Context, Args[ArgIdx]); 6301 6302 bool HasNonRecordCandidateType = false; 6303 bool HasArithmeticOrEnumeralCandidateType = false; 6304 SmallVector<BuiltinCandidateTypeSet, 2> CandidateTypes; 6305 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6306 CandidateTypes.push_back(BuiltinCandidateTypeSet(*this)); 6307 CandidateTypes[ArgIdx].AddTypesConvertedFrom(Args[ArgIdx]->getType(), 6308 OpLoc, 6309 true, 6310 (Op == OO_Exclaim || 6311 Op == OO_AmpAmp || 6312 Op == OO_PipePipe), 6313 VisibleTypeConversionsQuals); 6314 HasNonRecordCandidateType = HasNonRecordCandidateType || 6315 CandidateTypes[ArgIdx].hasNonRecordTypes(); 6316 HasArithmeticOrEnumeralCandidateType = 6317 HasArithmeticOrEnumeralCandidateType || 6318 CandidateTypes[ArgIdx].hasArithmeticOrEnumeralTypes(); 6319 } 6320 6321 // Exit early when no non-record types have been added to the candidate set 6322 // for any of the arguments to the operator. 6323 if (!HasNonRecordCandidateType) 6324 return; 6325 6326 // Setup an object to manage the common state for building overloads. 6327 BuiltinOperatorOverloadBuilder OpBuilder(*this, Args, NumArgs, 6328 VisibleTypeConversionsQuals, 6329 HasArithmeticOrEnumeralCandidateType, 6330 CandidateTypes, CandidateSet); 6331 6332 // Dispatch over the operation to add in only those overloads which apply. 6333 switch (Op) { 6334 case OO_None: 6335 case NUM_OVERLOADED_OPERATORS: 6336 llvm_unreachable("Expected an overloaded operator"); 6337 6338 case OO_New: 6339 case OO_Delete: 6340 case OO_Array_New: 6341 case OO_Array_Delete: 6342 case OO_Call: 6343 llvm_unreachable( 6344 "Special operators don't use AddBuiltinOperatorCandidates"); 6345 6346 case OO_Comma: 6347 case OO_Arrow: 6348 // C++ [over.match.oper]p3: 6349 // -- For the operator ',', the unary operator '&', or the 6350 // operator '->', the built-in candidates set is empty. 6351 break; 6352 6353 case OO_Plus: // '+' is either unary or binary 6354 if (NumArgs == 1) 6355 OpBuilder.addUnaryPlusPointerOverloads(); 6356 // Fall through. 6357 6358 case OO_Minus: // '-' is either unary or binary 6359 if (NumArgs == 1) { 6360 OpBuilder.addUnaryPlusOrMinusArithmeticOverloads(); 6361 } else { 6362 OpBuilder.addBinaryPlusOrMinusPointerOverloads(Op); 6363 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6364 } 6365 break; 6366 6367 case OO_Star: // '*' is either unary or binary 6368 if (NumArgs == 1) 6369 OpBuilder.addUnaryStarPointerOverloads(); 6370 else 6371 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6372 break; 6373 6374 case OO_Slash: 6375 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6376 break; 6377 6378 case OO_PlusPlus: 6379 case OO_MinusMinus: 6380 OpBuilder.addPlusPlusMinusMinusArithmeticOverloads(Op); 6381 OpBuilder.addPlusPlusMinusMinusPointerOverloads(); 6382 break; 6383 6384 case OO_EqualEqual: 6385 case OO_ExclaimEqual: 6386 OpBuilder.addEqualEqualOrNotEqualMemberPointerOverloads(); 6387 // Fall through. 6388 6389 case OO_Less: 6390 case OO_Greater: 6391 case OO_LessEqual: 6392 case OO_GreaterEqual: 6393 OpBuilder.addRelationalPointerOrEnumeralOverloads(); 6394 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/true); 6395 break; 6396 6397 case OO_Percent: 6398 case OO_Caret: 6399 case OO_Pipe: 6400 case OO_LessLess: 6401 case OO_GreaterGreater: 6402 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6403 break; 6404 6405 case OO_Amp: // '&' is either unary or binary 6406 if (NumArgs == 1) 6407 // C++ [over.match.oper]p3: 6408 // -- For the operator ',', the unary operator '&', or the 6409 // operator '->', the built-in candidates set is empty. 6410 break; 6411 6412 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6413 break; 6414 6415 case OO_Tilde: 6416 OpBuilder.addUnaryTildePromotedIntegralOverloads(); 6417 break; 6418 6419 case OO_Equal: 6420 OpBuilder.addAssignmentMemberPointerOrEnumeralOverloads(); 6421 // Fall through. 6422 6423 case OO_PlusEqual: 6424 case OO_MinusEqual: 6425 OpBuilder.addAssignmentPointerOverloads(Op == OO_Equal); 6426 // Fall through. 6427 6428 case OO_StarEqual: 6429 case OO_SlashEqual: 6430 OpBuilder.addAssignmentArithmeticOverloads(Op == OO_Equal); 6431 break; 6432 6433 case OO_PercentEqual: 6434 case OO_LessLessEqual: 6435 case OO_GreaterGreaterEqual: 6436 case OO_AmpEqual: 6437 case OO_CaretEqual: 6438 case OO_PipeEqual: 6439 OpBuilder.addAssignmentIntegralOverloads(); 6440 break; 6441 6442 case OO_Exclaim: 6443 OpBuilder.addExclaimOverload(); 6444 break; 6445 6446 case OO_AmpAmp: 6447 case OO_PipePipe: 6448 OpBuilder.addAmpAmpOrPipePipeOverload(); 6449 break; 6450 6451 case OO_Subscript: 6452 OpBuilder.addSubscriptOverloads(); 6453 break; 6454 6455 case OO_ArrowStar: 6456 OpBuilder.addArrowStarOverloads(); 6457 break; 6458 6459 case OO_Conditional: 6460 OpBuilder.addConditionalOperatorOverloads(); 6461 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6462 break; 6463 } 6464} 6465 6466/// \brief Add function candidates found via argument-dependent lookup 6467/// to the set of overloading candidates. 6468/// 6469/// This routine performs argument-dependent name lookup based on the 6470/// given function name (which may also be an operator name) and adds 6471/// all of the overload candidates found by ADL to the overload 6472/// candidate set (C++ [basic.lookup.argdep]). 6473void 6474Sema::AddArgumentDependentLookupCandidates(DeclarationName Name, 6475 bool Operator, 6476 Expr **Args, unsigned NumArgs, 6477 TemplateArgumentListInfo *ExplicitTemplateArgs, 6478 OverloadCandidateSet& CandidateSet, 6479 bool PartialOverloading, 6480 bool StdNamespaceIsAssociated) { 6481 ADLResult Fns; 6482 6483 // FIXME: This approach for uniquing ADL results (and removing 6484 // redundant candidates from the set) relies on pointer-equality, 6485 // which means we need to key off the canonical decl. However, 6486 // always going back to the canonical decl might not get us the 6487 // right set of default arguments. What default arguments are 6488 // we supposed to consider on ADL candidates, anyway? 6489 6490 // FIXME: Pass in the explicit template arguments? 6491 ArgumentDependentLookup(Name, Operator, Args, NumArgs, Fns, 6492 StdNamespaceIsAssociated); 6493 6494 // Erase all of the candidates we already knew about. 6495 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(), 6496 CandEnd = CandidateSet.end(); 6497 Cand != CandEnd; ++Cand) 6498 if (Cand->Function) { 6499 Fns.erase(Cand->Function); 6500 if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate()) 6501 Fns.erase(FunTmpl); 6502 } 6503 6504 // For each of the ADL candidates we found, add it to the overload 6505 // set. 6506 for (ADLResult::iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) { 6507 DeclAccessPair FoundDecl = DeclAccessPair::make(*I, AS_none); 6508 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) { 6509 if (ExplicitTemplateArgs) 6510 continue; 6511 6512 AddOverloadCandidate(FD, FoundDecl, Args, NumArgs, CandidateSet, 6513 false, PartialOverloading); 6514 } else 6515 AddTemplateOverloadCandidate(cast<FunctionTemplateDecl>(*I), 6516 FoundDecl, ExplicitTemplateArgs, 6517 Args, NumArgs, CandidateSet); 6518 } 6519} 6520 6521/// isBetterOverloadCandidate - Determines whether the first overload 6522/// candidate is a better candidate than the second (C++ 13.3.3p1). 6523bool 6524isBetterOverloadCandidate(Sema &S, 6525 const OverloadCandidate &Cand1, 6526 const OverloadCandidate &Cand2, 6527 SourceLocation Loc, 6528 bool UserDefinedConversion) { 6529 // Define viable functions to be better candidates than non-viable 6530 // functions. 6531 if (!Cand2.Viable) 6532 return Cand1.Viable; 6533 else if (!Cand1.Viable) 6534 return false; 6535 6536 // C++ [over.match.best]p1: 6537 // 6538 // -- if F is a static member function, ICS1(F) is defined such 6539 // that ICS1(F) is neither better nor worse than ICS1(G) for 6540 // any function G, and, symmetrically, ICS1(G) is neither 6541 // better nor worse than ICS1(F). 6542 unsigned StartArg = 0; 6543 if (Cand1.IgnoreObjectArgument || Cand2.IgnoreObjectArgument) 6544 StartArg = 1; 6545 6546 // C++ [over.match.best]p1: 6547 // A viable function F1 is defined to be a better function than another 6548 // viable function F2 if for all arguments i, ICSi(F1) is not a worse 6549 // conversion sequence than ICSi(F2), and then... 6550 unsigned NumArgs = Cand1.Conversions.size(); 6551 assert(Cand2.Conversions.size() == NumArgs && "Overload candidate mismatch"); 6552 bool HasBetterConversion = false; 6553 for (unsigned ArgIdx = StartArg; ArgIdx < NumArgs; ++ArgIdx) { 6554 switch (CompareImplicitConversionSequences(S, 6555 Cand1.Conversions[ArgIdx], 6556 Cand2.Conversions[ArgIdx])) { 6557 case ImplicitConversionSequence::Better: 6558 // Cand1 has a better conversion sequence. 6559 HasBetterConversion = true; 6560 break; 6561 6562 case ImplicitConversionSequence::Worse: 6563 // Cand1 can't be better than Cand2. 6564 return false; 6565 6566 case ImplicitConversionSequence::Indistinguishable: 6567 // Do nothing. 6568 break; 6569 } 6570 } 6571 6572 // -- for some argument j, ICSj(F1) is a better conversion sequence than 6573 // ICSj(F2), or, if not that, 6574 if (HasBetterConversion) 6575 return true; 6576 6577 // - F1 is a non-template function and F2 is a function template 6578 // specialization, or, if not that, 6579 if ((!Cand1.Function || !Cand1.Function->getPrimaryTemplate()) && 6580 Cand2.Function && Cand2.Function->getPrimaryTemplate()) 6581 return true; 6582 6583 // -- F1 and F2 are function template specializations, and the function 6584 // template for F1 is more specialized than the template for F2 6585 // according to the partial ordering rules described in 14.5.5.2, or, 6586 // if not that, 6587 if (Cand1.Function && Cand1.Function->getPrimaryTemplate() && 6588 Cand2.Function && Cand2.Function->getPrimaryTemplate()) { 6589 if (FunctionTemplateDecl *BetterTemplate 6590 = S.getMoreSpecializedTemplate(Cand1.Function->getPrimaryTemplate(), 6591 Cand2.Function->getPrimaryTemplate(), 6592 Loc, 6593 isa<CXXConversionDecl>(Cand1.Function)? TPOC_Conversion 6594 : TPOC_Call, 6595 Cand1.ExplicitCallArguments)) 6596 return BetterTemplate == Cand1.Function->getPrimaryTemplate(); 6597 } 6598 6599 // -- the context is an initialization by user-defined conversion 6600 // (see 8.5, 13.3.1.5) and the standard conversion sequence 6601 // from the return type of F1 to the destination type (i.e., 6602 // the type of the entity being initialized) is a better 6603 // conversion sequence than the standard conversion sequence 6604 // from the return type of F2 to the destination type. 6605 if (UserDefinedConversion && Cand1.Function && Cand2.Function && 6606 isa<CXXConversionDecl>(Cand1.Function) && 6607 isa<CXXConversionDecl>(Cand2.Function)) { 6608 switch (CompareStandardConversionSequences(S, 6609 Cand1.FinalConversion, 6610 Cand2.FinalConversion)) { 6611 case ImplicitConversionSequence::Better: 6612 // Cand1 has a better conversion sequence. 6613 return true; 6614 6615 case ImplicitConversionSequence::Worse: 6616 // Cand1 can't be better than Cand2. 6617 return false; 6618 6619 case ImplicitConversionSequence::Indistinguishable: 6620 // Do nothing 6621 break; 6622 } 6623 } 6624 6625 return false; 6626} 6627 6628/// \brief Computes the best viable function (C++ 13.3.3) 6629/// within an overload candidate set. 6630/// 6631/// \param CandidateSet the set of candidate functions. 6632/// 6633/// \param Loc the location of the function name (or operator symbol) for 6634/// which overload resolution occurs. 6635/// 6636/// \param Best f overload resolution was successful or found a deleted 6637/// function, Best points to the candidate function found. 6638/// 6639/// \returns The result of overload resolution. 6640OverloadingResult 6641OverloadCandidateSet::BestViableFunction(Sema &S, SourceLocation Loc, 6642 iterator &Best, 6643 bool UserDefinedConversion) { 6644 // Find the best viable function. 6645 Best = end(); 6646 for (iterator Cand = begin(); Cand != end(); ++Cand) { 6647 if (Cand->Viable) 6648 if (Best == end() || isBetterOverloadCandidate(S, *Cand, *Best, Loc, 6649 UserDefinedConversion)) 6650 Best = Cand; 6651 } 6652 6653 // If we didn't find any viable functions, abort. 6654 if (Best == end()) 6655 return OR_No_Viable_Function; 6656 6657 // Make sure that this function is better than every other viable 6658 // function. If not, we have an ambiguity. 6659 for (iterator Cand = begin(); Cand != end(); ++Cand) { 6660 if (Cand->Viable && 6661 Cand != Best && 6662 !isBetterOverloadCandidate(S, *Best, *Cand, Loc, 6663 UserDefinedConversion)) { 6664 Best = end(); 6665 return OR_Ambiguous; 6666 } 6667 } 6668 6669 // Best is the best viable function. 6670 if (Best->Function && 6671 (Best->Function->isDeleted() || 6672 S.isFunctionConsideredUnavailable(Best->Function))) 6673 return OR_Deleted; 6674 6675 return OR_Success; 6676} 6677 6678namespace { 6679 6680enum OverloadCandidateKind { 6681 oc_function, 6682 oc_method, 6683 oc_constructor, 6684 oc_function_template, 6685 oc_method_template, 6686 oc_constructor_template, 6687 oc_implicit_default_constructor, 6688 oc_implicit_copy_constructor, 6689 oc_implicit_move_constructor, 6690 oc_implicit_copy_assignment, 6691 oc_implicit_move_assignment, 6692 oc_implicit_inherited_constructor 6693}; 6694 6695OverloadCandidateKind ClassifyOverloadCandidate(Sema &S, 6696 FunctionDecl *Fn, 6697 std::string &Description) { 6698 bool isTemplate = false; 6699 6700 if (FunctionTemplateDecl *FunTmpl = Fn->getPrimaryTemplate()) { 6701 isTemplate = true; 6702 Description = S.getTemplateArgumentBindingsText( 6703 FunTmpl->getTemplateParameters(), *Fn->getTemplateSpecializationArgs()); 6704 } 6705 6706 if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn)) { 6707 if (!Ctor->isImplicit()) 6708 return isTemplate ? oc_constructor_template : oc_constructor; 6709 6710 if (Ctor->getInheritedConstructor()) 6711 return oc_implicit_inherited_constructor; 6712 6713 if (Ctor->isDefaultConstructor()) 6714 return oc_implicit_default_constructor; 6715 6716 if (Ctor->isMoveConstructor()) 6717 return oc_implicit_move_constructor; 6718 6719 assert(Ctor->isCopyConstructor() && 6720 "unexpected sort of implicit constructor"); 6721 return oc_implicit_copy_constructor; 6722 } 6723 6724 if (CXXMethodDecl *Meth = dyn_cast<CXXMethodDecl>(Fn)) { 6725 // This actually gets spelled 'candidate function' for now, but 6726 // it doesn't hurt to split it out. 6727 if (!Meth->isImplicit()) 6728 return isTemplate ? oc_method_template : oc_method; 6729 6730 if (Meth->isMoveAssignmentOperator()) 6731 return oc_implicit_move_assignment; 6732 6733 assert(Meth->isCopyAssignmentOperator() 6734 && "implicit method is not copy assignment operator?"); 6735 return oc_implicit_copy_assignment; 6736 } 6737 6738 return isTemplate ? oc_function_template : oc_function; 6739} 6740 6741void MaybeEmitInheritedConstructorNote(Sema &S, FunctionDecl *Fn) { 6742 const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn); 6743 if (!Ctor) return; 6744 6745 Ctor = Ctor->getInheritedConstructor(); 6746 if (!Ctor) return; 6747 6748 S.Diag(Ctor->getLocation(), diag::note_ovl_candidate_inherited_constructor); 6749} 6750 6751} // end anonymous namespace 6752 6753// Notes the location of an overload candidate. 6754void Sema::NoteOverloadCandidate(FunctionDecl *Fn) { 6755 std::string FnDesc; 6756 OverloadCandidateKind K = ClassifyOverloadCandidate(*this, Fn, FnDesc); 6757 Diag(Fn->getLocation(), diag::note_ovl_candidate) 6758 << (unsigned) K << FnDesc; 6759 MaybeEmitInheritedConstructorNote(*this, Fn); 6760} 6761 6762//Notes the location of all overload candidates designated through 6763// OverloadedExpr 6764void Sema::NoteAllOverloadCandidates(Expr* OverloadedExpr) { 6765 assert(OverloadedExpr->getType() == Context.OverloadTy); 6766 6767 OverloadExpr::FindResult Ovl = OverloadExpr::find(OverloadedExpr); 6768 OverloadExpr *OvlExpr = Ovl.Expression; 6769 6770 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 6771 IEnd = OvlExpr->decls_end(); 6772 I != IEnd; ++I) { 6773 if (FunctionTemplateDecl *FunTmpl = 6774 dyn_cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()) ) { 6775 NoteOverloadCandidate(FunTmpl->getTemplatedDecl()); 6776 } else if (FunctionDecl *Fun 6777 = dyn_cast<FunctionDecl>((*I)->getUnderlyingDecl()) ) { 6778 NoteOverloadCandidate(Fun); 6779 } 6780 } 6781} 6782 6783/// Diagnoses an ambiguous conversion. The partial diagnostic is the 6784/// "lead" diagnostic; it will be given two arguments, the source and 6785/// target types of the conversion. 6786void ImplicitConversionSequence::DiagnoseAmbiguousConversion( 6787 Sema &S, 6788 SourceLocation CaretLoc, 6789 const PartialDiagnostic &PDiag) const { 6790 S.Diag(CaretLoc, PDiag) 6791 << Ambiguous.getFromType() << Ambiguous.getToType(); 6792 for (AmbiguousConversionSequence::const_iterator 6793 I = Ambiguous.begin(), E = Ambiguous.end(); I != E; ++I) { 6794 S.NoteOverloadCandidate(*I); 6795 } 6796} 6797 6798namespace { 6799 6800void DiagnoseBadConversion(Sema &S, OverloadCandidate *Cand, unsigned I) { 6801 const ImplicitConversionSequence &Conv = Cand->Conversions[I]; 6802 assert(Conv.isBad()); 6803 assert(Cand->Function && "for now, candidate must be a function"); 6804 FunctionDecl *Fn = Cand->Function; 6805 6806 // There's a conversion slot for the object argument if this is a 6807 // non-constructor method. Note that 'I' corresponds the 6808 // conversion-slot index. 6809 bool isObjectArgument = false; 6810 if (isa<CXXMethodDecl>(Fn) && !isa<CXXConstructorDecl>(Fn)) { 6811 if (I == 0) 6812 isObjectArgument = true; 6813 else 6814 I--; 6815 } 6816 6817 std::string FnDesc; 6818 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 6819 6820 Expr *FromExpr = Conv.Bad.FromExpr; 6821 QualType FromTy = Conv.Bad.getFromType(); 6822 QualType ToTy = Conv.Bad.getToType(); 6823 6824 if (FromTy == S.Context.OverloadTy) { 6825 assert(FromExpr && "overload set argument came from implicit argument?"); 6826 Expr *E = FromExpr->IgnoreParens(); 6827 if (isa<UnaryOperator>(E)) 6828 E = cast<UnaryOperator>(E)->getSubExpr()->IgnoreParens(); 6829 DeclarationName Name = cast<OverloadExpr>(E)->getName(); 6830 6831 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_overload) 6832 << (unsigned) FnKind << FnDesc 6833 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6834 << ToTy << Name << I+1; 6835 MaybeEmitInheritedConstructorNote(S, Fn); 6836 return; 6837 } 6838 6839 // Do some hand-waving analysis to see if the non-viability is due 6840 // to a qualifier mismatch. 6841 CanQualType CFromTy = S.Context.getCanonicalType(FromTy); 6842 CanQualType CToTy = S.Context.getCanonicalType(ToTy); 6843 if (CanQual<ReferenceType> RT = CToTy->getAs<ReferenceType>()) 6844 CToTy = RT->getPointeeType(); 6845 else { 6846 // TODO: detect and diagnose the full richness of const mismatches. 6847 if (CanQual<PointerType> FromPT = CFromTy->getAs<PointerType>()) 6848 if (CanQual<PointerType> ToPT = CToTy->getAs<PointerType>()) 6849 CFromTy = FromPT->getPointeeType(), CToTy = ToPT->getPointeeType(); 6850 } 6851 6852 if (CToTy.getUnqualifiedType() == CFromTy.getUnqualifiedType() && 6853 !CToTy.isAtLeastAsQualifiedAs(CFromTy)) { 6854 // It is dumb that we have to do this here. 6855 while (isa<ArrayType>(CFromTy)) 6856 CFromTy = CFromTy->getAs<ArrayType>()->getElementType(); 6857 while (isa<ArrayType>(CToTy)) 6858 CToTy = CFromTy->getAs<ArrayType>()->getElementType(); 6859 6860 Qualifiers FromQs = CFromTy.getQualifiers(); 6861 Qualifiers ToQs = CToTy.getQualifiers(); 6862 6863 if (FromQs.getAddressSpace() != ToQs.getAddressSpace()) { 6864 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_addrspace) 6865 << (unsigned) FnKind << FnDesc 6866 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6867 << FromTy 6868 << FromQs.getAddressSpace() << ToQs.getAddressSpace() 6869 << (unsigned) isObjectArgument << I+1; 6870 MaybeEmitInheritedConstructorNote(S, Fn); 6871 return; 6872 } 6873 6874 if (FromQs.getObjCLifetime() != ToQs.getObjCLifetime()) { 6875 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_ownership) 6876 << (unsigned) FnKind << FnDesc 6877 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6878 << FromTy 6879 << FromQs.getObjCLifetime() << ToQs.getObjCLifetime() 6880 << (unsigned) isObjectArgument << I+1; 6881 MaybeEmitInheritedConstructorNote(S, Fn); 6882 return; 6883 } 6884 6885 if (FromQs.getObjCGCAttr() != ToQs.getObjCGCAttr()) { 6886 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_gc) 6887 << (unsigned) FnKind << FnDesc 6888 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6889 << FromTy 6890 << FromQs.getObjCGCAttr() << ToQs.getObjCGCAttr() 6891 << (unsigned) isObjectArgument << I+1; 6892 MaybeEmitInheritedConstructorNote(S, Fn); 6893 return; 6894 } 6895 6896 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 6897 assert(CVR && "unexpected qualifiers mismatch"); 6898 6899 if (isObjectArgument) { 6900 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr_this) 6901 << (unsigned) FnKind << FnDesc 6902 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6903 << FromTy << (CVR - 1); 6904 } else { 6905 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr) 6906 << (unsigned) FnKind << FnDesc 6907 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6908 << FromTy << (CVR - 1) << I+1; 6909 } 6910 MaybeEmitInheritedConstructorNote(S, Fn); 6911 return; 6912 } 6913 6914 // Diagnose references or pointers to incomplete types differently, 6915 // since it's far from impossible that the incompleteness triggered 6916 // the failure. 6917 QualType TempFromTy = FromTy.getNonReferenceType(); 6918 if (const PointerType *PTy = TempFromTy->getAs<PointerType>()) 6919 TempFromTy = PTy->getPointeeType(); 6920 if (TempFromTy->isIncompleteType()) { 6921 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv_incomplete) 6922 << (unsigned) FnKind << FnDesc 6923 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6924 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 6925 MaybeEmitInheritedConstructorNote(S, Fn); 6926 return; 6927 } 6928 6929 // Diagnose base -> derived pointer conversions. 6930 unsigned BaseToDerivedConversion = 0; 6931 if (const PointerType *FromPtrTy = FromTy->getAs<PointerType>()) { 6932 if (const PointerType *ToPtrTy = ToTy->getAs<PointerType>()) { 6933 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 6934 FromPtrTy->getPointeeType()) && 6935 !FromPtrTy->getPointeeType()->isIncompleteType() && 6936 !ToPtrTy->getPointeeType()->isIncompleteType() && 6937 S.IsDerivedFrom(ToPtrTy->getPointeeType(), 6938 FromPtrTy->getPointeeType())) 6939 BaseToDerivedConversion = 1; 6940 } 6941 } else if (const ObjCObjectPointerType *FromPtrTy 6942 = FromTy->getAs<ObjCObjectPointerType>()) { 6943 if (const ObjCObjectPointerType *ToPtrTy 6944 = ToTy->getAs<ObjCObjectPointerType>()) 6945 if (const ObjCInterfaceDecl *FromIface = FromPtrTy->getInterfaceDecl()) 6946 if (const ObjCInterfaceDecl *ToIface = ToPtrTy->getInterfaceDecl()) 6947 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 6948 FromPtrTy->getPointeeType()) && 6949 FromIface->isSuperClassOf(ToIface)) 6950 BaseToDerivedConversion = 2; 6951 } else if (const ReferenceType *ToRefTy = ToTy->getAs<ReferenceType>()) { 6952 if (ToRefTy->getPointeeType().isAtLeastAsQualifiedAs(FromTy) && 6953 !FromTy->isIncompleteType() && 6954 !ToRefTy->getPointeeType()->isIncompleteType() && 6955 S.IsDerivedFrom(ToRefTy->getPointeeType(), FromTy)) 6956 BaseToDerivedConversion = 3; 6957 } 6958 6959 if (BaseToDerivedConversion) { 6960 S.Diag(Fn->getLocation(), 6961 diag::note_ovl_candidate_bad_base_to_derived_conv) 6962 << (unsigned) FnKind << FnDesc 6963 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6964 << (BaseToDerivedConversion - 1) 6965 << FromTy << ToTy << I+1; 6966 MaybeEmitInheritedConstructorNote(S, Fn); 6967 return; 6968 } 6969 6970 if (isa<ObjCObjectPointerType>(CFromTy) && 6971 isa<PointerType>(CToTy)) { 6972 Qualifiers FromQs = CFromTy.getQualifiers(); 6973 Qualifiers ToQs = CToTy.getQualifiers(); 6974 if (FromQs.getObjCLifetime() != ToQs.getObjCLifetime()) { 6975 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_arc_conv) 6976 << (unsigned) FnKind << FnDesc 6977 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6978 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 6979 MaybeEmitInheritedConstructorNote(S, Fn); 6980 return; 6981 } 6982 } 6983 6984 // Emit the generic diagnostic and, optionally, add the hints to it. 6985 PartialDiagnostic FDiag = S.PDiag(diag::note_ovl_candidate_bad_conv); 6986 FDiag << (unsigned) FnKind << FnDesc 6987 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6988 << FromTy << ToTy << (unsigned) isObjectArgument << I + 1 6989 << (unsigned) (Cand->Fix.Kind); 6990 6991 // If we can fix the conversion, suggest the FixIts. 6992 for (SmallVector<FixItHint, 1>::iterator 6993 HI = Cand->Fix.Hints.begin(), HE = Cand->Fix.Hints.end(); 6994 HI != HE; ++HI) 6995 FDiag << *HI; 6996 S.Diag(Fn->getLocation(), FDiag); 6997 6998 MaybeEmitInheritedConstructorNote(S, Fn); 6999} 7000 7001void DiagnoseArityMismatch(Sema &S, OverloadCandidate *Cand, 7002 unsigned NumFormalArgs) { 7003 // TODO: treat calls to a missing default constructor as a special case 7004 7005 FunctionDecl *Fn = Cand->Function; 7006 const FunctionProtoType *FnTy = Fn->getType()->getAs<FunctionProtoType>(); 7007 7008 unsigned MinParams = Fn->getMinRequiredArguments(); 7009 7010 // With invalid overloaded operators, it's possible that we think we 7011 // have an arity mismatch when it fact it looks like we have the 7012 // right number of arguments, because only overloaded operators have 7013 // the weird behavior of overloading member and non-member functions. 7014 // Just don't report anything. 7015 if (Fn->isInvalidDecl() && 7016 Fn->getDeclName().getNameKind() == DeclarationName::CXXOperatorName) 7017 return; 7018 7019 // at least / at most / exactly 7020 unsigned mode, modeCount; 7021 if (NumFormalArgs < MinParams) { 7022 assert((Cand->FailureKind == ovl_fail_too_few_arguments) || 7023 (Cand->FailureKind == ovl_fail_bad_deduction && 7024 Cand->DeductionFailure.Result == Sema::TDK_TooFewArguments)); 7025 if (MinParams != FnTy->getNumArgs() || 7026 FnTy->isVariadic() || FnTy->isTemplateVariadic()) 7027 mode = 0; // "at least" 7028 else 7029 mode = 2; // "exactly" 7030 modeCount = MinParams; 7031 } else { 7032 assert((Cand->FailureKind == ovl_fail_too_many_arguments) || 7033 (Cand->FailureKind == ovl_fail_bad_deduction && 7034 Cand->DeductionFailure.Result == Sema::TDK_TooManyArguments)); 7035 if (MinParams != FnTy->getNumArgs()) 7036 mode = 1; // "at most" 7037 else 7038 mode = 2; // "exactly" 7039 modeCount = FnTy->getNumArgs(); 7040 } 7041 7042 std::string Description; 7043 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, Description); 7044 7045 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity) 7046 << (unsigned) FnKind << (Fn->getDescribedFunctionTemplate() != 0) << mode 7047 << modeCount << NumFormalArgs; 7048 MaybeEmitInheritedConstructorNote(S, Fn); 7049} 7050 7051/// Diagnose a failed template-argument deduction. 7052void DiagnoseBadDeduction(Sema &S, OverloadCandidate *Cand, 7053 Expr **Args, unsigned NumArgs) { 7054 FunctionDecl *Fn = Cand->Function; // pattern 7055 7056 TemplateParameter Param = Cand->DeductionFailure.getTemplateParameter(); 7057 NamedDecl *ParamD; 7058 (ParamD = Param.dyn_cast<TemplateTypeParmDecl*>()) || 7059 (ParamD = Param.dyn_cast<NonTypeTemplateParmDecl*>()) || 7060 (ParamD = Param.dyn_cast<TemplateTemplateParmDecl*>()); 7061 switch (Cand->DeductionFailure.Result) { 7062 case Sema::TDK_Success: 7063 llvm_unreachable("TDK_success while diagnosing bad deduction"); 7064 7065 case Sema::TDK_Incomplete: { 7066 assert(ParamD && "no parameter found for incomplete deduction result"); 7067 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_incomplete_deduction) 7068 << ParamD->getDeclName(); 7069 MaybeEmitInheritedConstructorNote(S, Fn); 7070 return; 7071 } 7072 7073 case Sema::TDK_Underqualified: { 7074 assert(ParamD && "no parameter found for bad qualifiers deduction result"); 7075 TemplateTypeParmDecl *TParam = cast<TemplateTypeParmDecl>(ParamD); 7076 7077 QualType Param = Cand->DeductionFailure.getFirstArg()->getAsType(); 7078 7079 // Param will have been canonicalized, but it should just be a 7080 // qualified version of ParamD, so move the qualifiers to that. 7081 QualifierCollector Qs; 7082 Qs.strip(Param); 7083 QualType NonCanonParam = Qs.apply(S.Context, TParam->getTypeForDecl()); 7084 assert(S.Context.hasSameType(Param, NonCanonParam)); 7085 7086 // Arg has also been canonicalized, but there's nothing we can do 7087 // about that. It also doesn't matter as much, because it won't 7088 // have any template parameters in it (because deduction isn't 7089 // done on dependent types). 7090 QualType Arg = Cand->DeductionFailure.getSecondArg()->getAsType(); 7091 7092 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_underqualified) 7093 << ParamD->getDeclName() << Arg << NonCanonParam; 7094 MaybeEmitInheritedConstructorNote(S, Fn); 7095 return; 7096 } 7097 7098 case Sema::TDK_Inconsistent: { 7099 assert(ParamD && "no parameter found for inconsistent deduction result"); 7100 int which = 0; 7101 if (isa<TemplateTypeParmDecl>(ParamD)) 7102 which = 0; 7103 else if (isa<NonTypeTemplateParmDecl>(ParamD)) 7104 which = 1; 7105 else { 7106 which = 2; 7107 } 7108 7109 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_inconsistent_deduction) 7110 << which << ParamD->getDeclName() 7111 << *Cand->DeductionFailure.getFirstArg() 7112 << *Cand->DeductionFailure.getSecondArg(); 7113 MaybeEmitInheritedConstructorNote(S, Fn); 7114 return; 7115 } 7116 7117 case Sema::TDK_InvalidExplicitArguments: 7118 assert(ParamD && "no parameter found for invalid explicit arguments"); 7119 if (ParamD->getDeclName()) 7120 S.Diag(Fn->getLocation(), 7121 diag::note_ovl_candidate_explicit_arg_mismatch_named) 7122 << ParamD->getDeclName(); 7123 else { 7124 int index = 0; 7125 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ParamD)) 7126 index = TTP->getIndex(); 7127 else if (NonTypeTemplateParmDecl *NTTP 7128 = dyn_cast<NonTypeTemplateParmDecl>(ParamD)) 7129 index = NTTP->getIndex(); 7130 else 7131 index = cast<TemplateTemplateParmDecl>(ParamD)->getIndex(); 7132 S.Diag(Fn->getLocation(), 7133 diag::note_ovl_candidate_explicit_arg_mismatch_unnamed) 7134 << (index + 1); 7135 } 7136 MaybeEmitInheritedConstructorNote(S, Fn); 7137 return; 7138 7139 case Sema::TDK_TooManyArguments: 7140 case Sema::TDK_TooFewArguments: 7141 DiagnoseArityMismatch(S, Cand, NumArgs); 7142 return; 7143 7144 case Sema::TDK_InstantiationDepth: 7145 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_instantiation_depth); 7146 MaybeEmitInheritedConstructorNote(S, Fn); 7147 return; 7148 7149 case Sema::TDK_SubstitutionFailure: { 7150 std::string ArgString; 7151 if (TemplateArgumentList *Args 7152 = Cand->DeductionFailure.getTemplateArgumentList()) 7153 ArgString = S.getTemplateArgumentBindingsText( 7154 Fn->getDescribedFunctionTemplate()->getTemplateParameters(), 7155 *Args); 7156 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_substitution_failure) 7157 << ArgString; 7158 MaybeEmitInheritedConstructorNote(S, Fn); 7159 return; 7160 } 7161 7162 // TODO: diagnose these individually, then kill off 7163 // note_ovl_candidate_bad_deduction, which is uselessly vague. 7164 case Sema::TDK_NonDeducedMismatch: 7165 case Sema::TDK_FailedOverloadResolution: 7166 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_deduction); 7167 MaybeEmitInheritedConstructorNote(S, Fn); 7168 return; 7169 } 7170} 7171 7172/// Generates a 'note' diagnostic for an overload candidate. We've 7173/// already generated a primary error at the call site. 7174/// 7175/// It really does need to be a single diagnostic with its caret 7176/// pointed at the candidate declaration. Yes, this creates some 7177/// major challenges of technical writing. Yes, this makes pointing 7178/// out problems with specific arguments quite awkward. It's still 7179/// better than generating twenty screens of text for every failed 7180/// overload. 7181/// 7182/// It would be great to be able to express per-candidate problems 7183/// more richly for those diagnostic clients that cared, but we'd 7184/// still have to be just as careful with the default diagnostics. 7185void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand, 7186 Expr **Args, unsigned NumArgs) { 7187 FunctionDecl *Fn = Cand->Function; 7188 7189 // Note deleted candidates, but only if they're viable. 7190 if (Cand->Viable && (Fn->isDeleted() || 7191 S.isFunctionConsideredUnavailable(Fn))) { 7192 std::string FnDesc; 7193 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 7194 7195 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_deleted) 7196 << FnKind << FnDesc << Fn->isDeleted(); 7197 MaybeEmitInheritedConstructorNote(S, Fn); 7198 return; 7199 } 7200 7201 // We don't really have anything else to say about viable candidates. 7202 if (Cand->Viable) { 7203 S.NoteOverloadCandidate(Fn); 7204 return; 7205 } 7206 7207 switch (Cand->FailureKind) { 7208 case ovl_fail_too_many_arguments: 7209 case ovl_fail_too_few_arguments: 7210 return DiagnoseArityMismatch(S, Cand, NumArgs); 7211 7212 case ovl_fail_bad_deduction: 7213 return DiagnoseBadDeduction(S, Cand, Args, NumArgs); 7214 7215 case ovl_fail_trivial_conversion: 7216 case ovl_fail_bad_final_conversion: 7217 case ovl_fail_final_conversion_not_exact: 7218 return S.NoteOverloadCandidate(Fn); 7219 7220 case ovl_fail_bad_conversion: { 7221 unsigned I = (Cand->IgnoreObjectArgument ? 1 : 0); 7222 for (unsigned N = Cand->Conversions.size(); I != N; ++I) 7223 if (Cand->Conversions[I].isBad()) 7224 return DiagnoseBadConversion(S, Cand, I); 7225 7226 // FIXME: this currently happens when we're called from SemaInit 7227 // when user-conversion overload fails. Figure out how to handle 7228 // those conditions and diagnose them well. 7229 return S.NoteOverloadCandidate(Fn); 7230 } 7231 } 7232} 7233 7234void NoteSurrogateCandidate(Sema &S, OverloadCandidate *Cand) { 7235 // Desugar the type of the surrogate down to a function type, 7236 // retaining as many typedefs as possible while still showing 7237 // the function type (and, therefore, its parameter types). 7238 QualType FnType = Cand->Surrogate->getConversionType(); 7239 bool isLValueReference = false; 7240 bool isRValueReference = false; 7241 bool isPointer = false; 7242 if (const LValueReferenceType *FnTypeRef = 7243 FnType->getAs<LValueReferenceType>()) { 7244 FnType = FnTypeRef->getPointeeType(); 7245 isLValueReference = true; 7246 } else if (const RValueReferenceType *FnTypeRef = 7247 FnType->getAs<RValueReferenceType>()) { 7248 FnType = FnTypeRef->getPointeeType(); 7249 isRValueReference = true; 7250 } 7251 if (const PointerType *FnTypePtr = FnType->getAs<PointerType>()) { 7252 FnType = FnTypePtr->getPointeeType(); 7253 isPointer = true; 7254 } 7255 // Desugar down to a function type. 7256 FnType = QualType(FnType->getAs<FunctionType>(), 0); 7257 // Reconstruct the pointer/reference as appropriate. 7258 if (isPointer) FnType = S.Context.getPointerType(FnType); 7259 if (isRValueReference) FnType = S.Context.getRValueReferenceType(FnType); 7260 if (isLValueReference) FnType = S.Context.getLValueReferenceType(FnType); 7261 7262 S.Diag(Cand->Surrogate->getLocation(), diag::note_ovl_surrogate_cand) 7263 << FnType; 7264 MaybeEmitInheritedConstructorNote(S, Cand->Surrogate); 7265} 7266 7267void NoteBuiltinOperatorCandidate(Sema &S, 7268 const char *Opc, 7269 SourceLocation OpLoc, 7270 OverloadCandidate *Cand) { 7271 assert(Cand->Conversions.size() <= 2 && "builtin operator is not binary"); 7272 std::string TypeStr("operator"); 7273 TypeStr += Opc; 7274 TypeStr += "("; 7275 TypeStr += Cand->BuiltinTypes.ParamTypes[0].getAsString(); 7276 if (Cand->Conversions.size() == 1) { 7277 TypeStr += ")"; 7278 S.Diag(OpLoc, diag::note_ovl_builtin_unary_candidate) << TypeStr; 7279 } else { 7280 TypeStr += ", "; 7281 TypeStr += Cand->BuiltinTypes.ParamTypes[1].getAsString(); 7282 TypeStr += ")"; 7283 S.Diag(OpLoc, diag::note_ovl_builtin_binary_candidate) << TypeStr; 7284 } 7285} 7286 7287void NoteAmbiguousUserConversions(Sema &S, SourceLocation OpLoc, 7288 OverloadCandidate *Cand) { 7289 unsigned NoOperands = Cand->Conversions.size(); 7290 for (unsigned ArgIdx = 0; ArgIdx < NoOperands; ++ArgIdx) { 7291 const ImplicitConversionSequence &ICS = Cand->Conversions[ArgIdx]; 7292 if (ICS.isBad()) break; // all meaningless after first invalid 7293 if (!ICS.isAmbiguous()) continue; 7294 7295 ICS.DiagnoseAmbiguousConversion(S, OpLoc, 7296 S.PDiag(diag::note_ambiguous_type_conversion)); 7297 } 7298} 7299 7300SourceLocation GetLocationForCandidate(const OverloadCandidate *Cand) { 7301 if (Cand->Function) 7302 return Cand->Function->getLocation(); 7303 if (Cand->IsSurrogate) 7304 return Cand->Surrogate->getLocation(); 7305 return SourceLocation(); 7306} 7307 7308static unsigned 7309RankDeductionFailure(const OverloadCandidate::DeductionFailureInfo &DFI) { 7310 switch ((Sema::TemplateDeductionResult)DFI.Result) { 7311 case Sema::TDK_Success: 7312 llvm_unreachable("TDK_success while diagnosing bad deduction"); 7313 7314 case Sema::TDK_Incomplete: 7315 return 1; 7316 7317 case Sema::TDK_Underqualified: 7318 case Sema::TDK_Inconsistent: 7319 return 2; 7320 7321 case Sema::TDK_SubstitutionFailure: 7322 case Sema::TDK_NonDeducedMismatch: 7323 return 3; 7324 7325 case Sema::TDK_InstantiationDepth: 7326 case Sema::TDK_FailedOverloadResolution: 7327 return 4; 7328 7329 case Sema::TDK_InvalidExplicitArguments: 7330 return 5; 7331 7332 case Sema::TDK_TooManyArguments: 7333 case Sema::TDK_TooFewArguments: 7334 return 6; 7335 } 7336 llvm_unreachable("Unhandled deduction result"); 7337} 7338 7339struct CompareOverloadCandidatesForDisplay { 7340 Sema &S; 7341 CompareOverloadCandidatesForDisplay(Sema &S) : S(S) {} 7342 7343 bool operator()(const OverloadCandidate *L, 7344 const OverloadCandidate *R) { 7345 // Fast-path this check. 7346 if (L == R) return false; 7347 7348 // Order first by viability. 7349 if (L->Viable) { 7350 if (!R->Viable) return true; 7351 7352 // TODO: introduce a tri-valued comparison for overload 7353 // candidates. Would be more worthwhile if we had a sort 7354 // that could exploit it. 7355 if (isBetterOverloadCandidate(S, *L, *R, SourceLocation())) return true; 7356 if (isBetterOverloadCandidate(S, *R, *L, SourceLocation())) return false; 7357 } else if (R->Viable) 7358 return false; 7359 7360 assert(L->Viable == R->Viable); 7361 7362 // Criteria by which we can sort non-viable candidates: 7363 if (!L->Viable) { 7364 // 1. Arity mismatches come after other candidates. 7365 if (L->FailureKind == ovl_fail_too_many_arguments || 7366 L->FailureKind == ovl_fail_too_few_arguments) 7367 return false; 7368 if (R->FailureKind == ovl_fail_too_many_arguments || 7369 R->FailureKind == ovl_fail_too_few_arguments) 7370 return true; 7371 7372 // 2. Bad conversions come first and are ordered by the number 7373 // of bad conversions and quality of good conversions. 7374 if (L->FailureKind == ovl_fail_bad_conversion) { 7375 if (R->FailureKind != ovl_fail_bad_conversion) 7376 return true; 7377 7378 // The conversion that can be fixed with a smaller number of changes, 7379 // comes first. 7380 unsigned numLFixes = L->Fix.NumConversionsFixed; 7381 unsigned numRFixes = R->Fix.NumConversionsFixed; 7382 numLFixes = (numLFixes == 0) ? UINT_MAX : numLFixes; 7383 numRFixes = (numRFixes == 0) ? UINT_MAX : numRFixes; 7384 if (numLFixes != numRFixes) { 7385 if (numLFixes < numRFixes) 7386 return true; 7387 else 7388 return false; 7389 } 7390 7391 // If there's any ordering between the defined conversions... 7392 // FIXME: this might not be transitive. 7393 assert(L->Conversions.size() == R->Conversions.size()); 7394 7395 int leftBetter = 0; 7396 unsigned I = (L->IgnoreObjectArgument || R->IgnoreObjectArgument); 7397 for (unsigned E = L->Conversions.size(); I != E; ++I) { 7398 switch (CompareImplicitConversionSequences(S, 7399 L->Conversions[I], 7400 R->Conversions[I])) { 7401 case ImplicitConversionSequence::Better: 7402 leftBetter++; 7403 break; 7404 7405 case ImplicitConversionSequence::Worse: 7406 leftBetter--; 7407 break; 7408 7409 case ImplicitConversionSequence::Indistinguishable: 7410 break; 7411 } 7412 } 7413 if (leftBetter > 0) return true; 7414 if (leftBetter < 0) return false; 7415 7416 } else if (R->FailureKind == ovl_fail_bad_conversion) 7417 return false; 7418 7419 if (L->FailureKind == ovl_fail_bad_deduction) { 7420 if (R->FailureKind != ovl_fail_bad_deduction) 7421 return true; 7422 7423 if (L->DeductionFailure.Result != R->DeductionFailure.Result) 7424 return RankDeductionFailure(L->DeductionFailure) 7425 <= RankDeductionFailure(R->DeductionFailure); 7426 } 7427 7428 // TODO: others? 7429 } 7430 7431 // Sort everything else by location. 7432 SourceLocation LLoc = GetLocationForCandidate(L); 7433 SourceLocation RLoc = GetLocationForCandidate(R); 7434 7435 // Put candidates without locations (e.g. builtins) at the end. 7436 if (LLoc.isInvalid()) return false; 7437 if (RLoc.isInvalid()) return true; 7438 7439 return S.SourceMgr.isBeforeInTranslationUnit(LLoc, RLoc); 7440 } 7441}; 7442 7443/// CompleteNonViableCandidate - Normally, overload resolution only 7444/// computes up to the first. Produces the FixIt set if possible. 7445void CompleteNonViableCandidate(Sema &S, OverloadCandidate *Cand, 7446 Expr **Args, unsigned NumArgs) { 7447 assert(!Cand->Viable); 7448 7449 // Don't do anything on failures other than bad conversion. 7450 if (Cand->FailureKind != ovl_fail_bad_conversion) return; 7451 7452 // We only want the FixIts if all the arguments can be corrected. 7453 bool Unfixable = false; 7454 // Use a implicit copy initialization to check conversion fixes. 7455 Cand->Fix.setConversionChecker(TryCopyInitialization); 7456 7457 // Skip forward to the first bad conversion. 7458 unsigned ConvIdx = (Cand->IgnoreObjectArgument ? 1 : 0); 7459 unsigned ConvCount = Cand->Conversions.size(); 7460 while (true) { 7461 assert(ConvIdx != ConvCount && "no bad conversion in candidate"); 7462 ConvIdx++; 7463 if (Cand->Conversions[ConvIdx - 1].isBad()) { 7464 Unfixable = !Cand->TryToFixBadConversion(ConvIdx - 1, S); 7465 break; 7466 } 7467 } 7468 7469 if (ConvIdx == ConvCount) 7470 return; 7471 7472 assert(!Cand->Conversions[ConvIdx].isInitialized() && 7473 "remaining conversion is initialized?"); 7474 7475 // FIXME: this should probably be preserved from the overload 7476 // operation somehow. 7477 bool SuppressUserConversions = false; 7478 7479 const FunctionProtoType* Proto; 7480 unsigned ArgIdx = ConvIdx; 7481 7482 if (Cand->IsSurrogate) { 7483 QualType ConvType 7484 = Cand->Surrogate->getConversionType().getNonReferenceType(); 7485 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 7486 ConvType = ConvPtrType->getPointeeType(); 7487 Proto = ConvType->getAs<FunctionProtoType>(); 7488 ArgIdx--; 7489 } else if (Cand->Function) { 7490 Proto = Cand->Function->getType()->getAs<FunctionProtoType>(); 7491 if (isa<CXXMethodDecl>(Cand->Function) && 7492 !isa<CXXConstructorDecl>(Cand->Function)) 7493 ArgIdx--; 7494 } else { 7495 // Builtin binary operator with a bad first conversion. 7496 assert(ConvCount <= 3); 7497 for (; ConvIdx != ConvCount; ++ConvIdx) 7498 Cand->Conversions[ConvIdx] 7499 = TryCopyInitialization(S, Args[ConvIdx], 7500 Cand->BuiltinTypes.ParamTypes[ConvIdx], 7501 SuppressUserConversions, 7502 /*InOverloadResolution*/ true, 7503 /*AllowObjCWritebackConversion=*/ 7504 S.getLangOptions().ObjCAutoRefCount); 7505 return; 7506 } 7507 7508 // Fill in the rest of the conversions. 7509 unsigned NumArgsInProto = Proto->getNumArgs(); 7510 for (; ConvIdx != ConvCount; ++ConvIdx, ++ArgIdx) { 7511 if (ArgIdx < NumArgsInProto) { 7512 Cand->Conversions[ConvIdx] 7513 = TryCopyInitialization(S, Args[ArgIdx], Proto->getArgType(ArgIdx), 7514 SuppressUserConversions, 7515 /*InOverloadResolution=*/true, 7516 /*AllowObjCWritebackConversion=*/ 7517 S.getLangOptions().ObjCAutoRefCount); 7518 // Store the FixIt in the candidate if it exists. 7519 if (!Unfixable && Cand->Conversions[ConvIdx].isBad()) 7520 Unfixable = !Cand->TryToFixBadConversion(ConvIdx, S); 7521 } 7522 else 7523 Cand->Conversions[ConvIdx].setEllipsis(); 7524 } 7525} 7526 7527} // end anonymous namespace 7528 7529/// PrintOverloadCandidates - When overload resolution fails, prints 7530/// diagnostic messages containing the candidates in the candidate 7531/// set. 7532void OverloadCandidateSet::NoteCandidates(Sema &S, 7533 OverloadCandidateDisplayKind OCD, 7534 Expr **Args, unsigned NumArgs, 7535 const char *Opc, 7536 SourceLocation OpLoc) { 7537 // Sort the candidates by viability and position. Sorting directly would 7538 // be prohibitive, so we make a set of pointers and sort those. 7539 SmallVector<OverloadCandidate*, 32> Cands; 7540 if (OCD == OCD_AllCandidates) Cands.reserve(size()); 7541 for (iterator Cand = begin(), LastCand = end(); Cand != LastCand; ++Cand) { 7542 if (Cand->Viable) 7543 Cands.push_back(Cand); 7544 else if (OCD == OCD_AllCandidates) { 7545 CompleteNonViableCandidate(S, Cand, Args, NumArgs); 7546 if (Cand->Function || Cand->IsSurrogate) 7547 Cands.push_back(Cand); 7548 // Otherwise, this a non-viable builtin candidate. We do not, in general, 7549 // want to list every possible builtin candidate. 7550 } 7551 } 7552 7553 std::sort(Cands.begin(), Cands.end(), 7554 CompareOverloadCandidatesForDisplay(S)); 7555 7556 bool ReportedAmbiguousConversions = false; 7557 7558 SmallVectorImpl<OverloadCandidate*>::iterator I, E; 7559 const Diagnostic::OverloadsShown ShowOverloads = S.Diags.getShowOverloads(); 7560 unsigned CandsShown = 0; 7561 for (I = Cands.begin(), E = Cands.end(); I != E; ++I) { 7562 OverloadCandidate *Cand = *I; 7563 7564 // Set an arbitrary limit on the number of candidate functions we'll spam 7565 // the user with. FIXME: This limit should depend on details of the 7566 // candidate list. 7567 if (CandsShown >= 4 && ShowOverloads == Diagnostic::Ovl_Best) { 7568 break; 7569 } 7570 ++CandsShown; 7571 7572 if (Cand->Function) 7573 NoteFunctionCandidate(S, Cand, Args, NumArgs); 7574 else if (Cand->IsSurrogate) 7575 NoteSurrogateCandidate(S, Cand); 7576 else { 7577 assert(Cand->Viable && 7578 "Non-viable built-in candidates are not added to Cands."); 7579 // Generally we only see ambiguities including viable builtin 7580 // operators if overload resolution got screwed up by an 7581 // ambiguous user-defined conversion. 7582 // 7583 // FIXME: It's quite possible for different conversions to see 7584 // different ambiguities, though. 7585 if (!ReportedAmbiguousConversions) { 7586 NoteAmbiguousUserConversions(S, OpLoc, Cand); 7587 ReportedAmbiguousConversions = true; 7588 } 7589 7590 // If this is a viable builtin, print it. 7591 NoteBuiltinOperatorCandidate(S, Opc, OpLoc, Cand); 7592 } 7593 } 7594 7595 if (I != E) 7596 S.Diag(OpLoc, diag::note_ovl_too_many_candidates) << int(E - I); 7597} 7598 7599// [PossiblyAFunctionType] --> [Return] 7600// NonFunctionType --> NonFunctionType 7601// R (A) --> R(A) 7602// R (*)(A) --> R (A) 7603// R (&)(A) --> R (A) 7604// R (S::*)(A) --> R (A) 7605QualType Sema::ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType) { 7606 QualType Ret = PossiblyAFunctionType; 7607 if (const PointerType *ToTypePtr = 7608 PossiblyAFunctionType->getAs<PointerType>()) 7609 Ret = ToTypePtr->getPointeeType(); 7610 else if (const ReferenceType *ToTypeRef = 7611 PossiblyAFunctionType->getAs<ReferenceType>()) 7612 Ret = ToTypeRef->getPointeeType(); 7613 else if (const MemberPointerType *MemTypePtr = 7614 PossiblyAFunctionType->getAs<MemberPointerType>()) 7615 Ret = MemTypePtr->getPointeeType(); 7616 Ret = 7617 Context.getCanonicalType(Ret).getUnqualifiedType(); 7618 return Ret; 7619} 7620 7621// A helper class to help with address of function resolution 7622// - allows us to avoid passing around all those ugly parameters 7623class AddressOfFunctionResolver 7624{ 7625 Sema& S; 7626 Expr* SourceExpr; 7627 const QualType& TargetType; 7628 QualType TargetFunctionType; // Extracted function type from target type 7629 7630 bool Complain; 7631 //DeclAccessPair& ResultFunctionAccessPair; 7632 ASTContext& Context; 7633 7634 bool TargetTypeIsNonStaticMemberFunction; 7635 bool FoundNonTemplateFunction; 7636 7637 OverloadExpr::FindResult OvlExprInfo; 7638 OverloadExpr *OvlExpr; 7639 TemplateArgumentListInfo OvlExplicitTemplateArgs; 7640 SmallVector<std::pair<DeclAccessPair, FunctionDecl*>, 4> Matches; 7641 7642public: 7643 AddressOfFunctionResolver(Sema &S, Expr* SourceExpr, 7644 const QualType& TargetType, bool Complain) 7645 : S(S), SourceExpr(SourceExpr), TargetType(TargetType), 7646 Complain(Complain), Context(S.getASTContext()), 7647 TargetTypeIsNonStaticMemberFunction( 7648 !!TargetType->getAs<MemberPointerType>()), 7649 FoundNonTemplateFunction(false), 7650 OvlExprInfo(OverloadExpr::find(SourceExpr)), 7651 OvlExpr(OvlExprInfo.Expression) 7652 { 7653 ExtractUnqualifiedFunctionTypeFromTargetType(); 7654 7655 if (!TargetFunctionType->isFunctionType()) { 7656 if (OvlExpr->hasExplicitTemplateArgs()) { 7657 DeclAccessPair dap; 7658 if (FunctionDecl* Fn = S.ResolveSingleFunctionTemplateSpecialization( 7659 OvlExpr, false, &dap) ) { 7660 7661 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 7662 if (!Method->isStatic()) { 7663 // If the target type is a non-function type and the function 7664 // found is a non-static member function, pretend as if that was 7665 // the target, it's the only possible type to end up with. 7666 TargetTypeIsNonStaticMemberFunction = true; 7667 7668 // And skip adding the function if its not in the proper form. 7669 // We'll diagnose this due to an empty set of functions. 7670 if (!OvlExprInfo.HasFormOfMemberPointer) 7671 return; 7672 } 7673 } 7674 7675 Matches.push_back(std::make_pair(dap,Fn)); 7676 } 7677 } 7678 return; 7679 } 7680 7681 if (OvlExpr->hasExplicitTemplateArgs()) 7682 OvlExpr->getExplicitTemplateArgs().copyInto(OvlExplicitTemplateArgs); 7683 7684 if (FindAllFunctionsThatMatchTargetTypeExactly()) { 7685 // C++ [over.over]p4: 7686 // If more than one function is selected, [...] 7687 if (Matches.size() > 1) { 7688 if (FoundNonTemplateFunction) 7689 EliminateAllTemplateMatches(); 7690 else 7691 EliminateAllExceptMostSpecializedTemplate(); 7692 } 7693 } 7694 } 7695 7696private: 7697 bool isTargetTypeAFunction() const { 7698 return TargetFunctionType->isFunctionType(); 7699 } 7700 7701 // [ToType] [Return] 7702 7703 // R (*)(A) --> R (A), IsNonStaticMemberFunction = false 7704 // R (&)(A) --> R (A), IsNonStaticMemberFunction = false 7705 // R (S::*)(A) --> R (A), IsNonStaticMemberFunction = true 7706 void inline ExtractUnqualifiedFunctionTypeFromTargetType() { 7707 TargetFunctionType = S.ExtractUnqualifiedFunctionType(TargetType); 7708 } 7709 7710 // return true if any matching specializations were found 7711 bool AddMatchingTemplateFunction(FunctionTemplateDecl* FunctionTemplate, 7712 const DeclAccessPair& CurAccessFunPair) { 7713 if (CXXMethodDecl *Method 7714 = dyn_cast<CXXMethodDecl>(FunctionTemplate->getTemplatedDecl())) { 7715 // Skip non-static function templates when converting to pointer, and 7716 // static when converting to member pointer. 7717 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 7718 return false; 7719 } 7720 else if (TargetTypeIsNonStaticMemberFunction) 7721 return false; 7722 7723 // C++ [over.over]p2: 7724 // If the name is a function template, template argument deduction is 7725 // done (14.8.2.2), and if the argument deduction succeeds, the 7726 // resulting template argument list is used to generate a single 7727 // function template specialization, which is added to the set of 7728 // overloaded functions considered. 7729 FunctionDecl *Specialization = 0; 7730 TemplateDeductionInfo Info(Context, OvlExpr->getNameLoc()); 7731 if (Sema::TemplateDeductionResult Result 7732 = S.DeduceTemplateArguments(FunctionTemplate, 7733 &OvlExplicitTemplateArgs, 7734 TargetFunctionType, Specialization, 7735 Info)) { 7736 // FIXME: make a note of the failed deduction for diagnostics. 7737 (void)Result; 7738 return false; 7739 } 7740 7741 // Template argument deduction ensures that we have an exact match. 7742 // This function template specicalization works. 7743 Specialization = cast<FunctionDecl>(Specialization->getCanonicalDecl()); 7744 assert(TargetFunctionType 7745 == Context.getCanonicalType(Specialization->getType())); 7746 Matches.push_back(std::make_pair(CurAccessFunPair, Specialization)); 7747 return true; 7748 } 7749 7750 bool AddMatchingNonTemplateFunction(NamedDecl* Fn, 7751 const DeclAccessPair& CurAccessFunPair) { 7752 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 7753 // Skip non-static functions when converting to pointer, and static 7754 // when converting to member pointer. 7755 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 7756 return false; 7757 } 7758 else if (TargetTypeIsNonStaticMemberFunction) 7759 return false; 7760 7761 if (FunctionDecl *FunDecl = dyn_cast<FunctionDecl>(Fn)) { 7762 QualType ResultTy; 7763 if (Context.hasSameUnqualifiedType(TargetFunctionType, 7764 FunDecl->getType()) || 7765 S.IsNoReturnConversion(FunDecl->getType(), TargetFunctionType, 7766 ResultTy)) { 7767 Matches.push_back(std::make_pair(CurAccessFunPair, 7768 cast<FunctionDecl>(FunDecl->getCanonicalDecl()))); 7769 FoundNonTemplateFunction = true; 7770 return true; 7771 } 7772 } 7773 7774 return false; 7775 } 7776 7777 bool FindAllFunctionsThatMatchTargetTypeExactly() { 7778 bool Ret = false; 7779 7780 // If the overload expression doesn't have the form of a pointer to 7781 // member, don't try to convert it to a pointer-to-member type. 7782 if (IsInvalidFormOfPointerToMemberFunction()) 7783 return false; 7784 7785 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 7786 E = OvlExpr->decls_end(); 7787 I != E; ++I) { 7788 // Look through any using declarations to find the underlying function. 7789 NamedDecl *Fn = (*I)->getUnderlyingDecl(); 7790 7791 // C++ [over.over]p3: 7792 // Non-member functions and static member functions match 7793 // targets of type "pointer-to-function" or "reference-to-function." 7794 // Nonstatic member functions match targets of 7795 // type "pointer-to-member-function." 7796 // Note that according to DR 247, the containing class does not matter. 7797 if (FunctionTemplateDecl *FunctionTemplate 7798 = dyn_cast<FunctionTemplateDecl>(Fn)) { 7799 if (AddMatchingTemplateFunction(FunctionTemplate, I.getPair())) 7800 Ret = true; 7801 } 7802 // If we have explicit template arguments supplied, skip non-templates. 7803 else if (!OvlExpr->hasExplicitTemplateArgs() && 7804 AddMatchingNonTemplateFunction(Fn, I.getPair())) 7805 Ret = true; 7806 } 7807 assert(Ret || Matches.empty()); 7808 return Ret; 7809 } 7810 7811 void EliminateAllExceptMostSpecializedTemplate() { 7812 // [...] and any given function template specialization F1 is 7813 // eliminated if the set contains a second function template 7814 // specialization whose function template is more specialized 7815 // than the function template of F1 according to the partial 7816 // ordering rules of 14.5.5.2. 7817 7818 // The algorithm specified above is quadratic. We instead use a 7819 // two-pass algorithm (similar to the one used to identify the 7820 // best viable function in an overload set) that identifies the 7821 // best function template (if it exists). 7822 7823 UnresolvedSet<4> MatchesCopy; // TODO: avoid! 7824 for (unsigned I = 0, E = Matches.size(); I != E; ++I) 7825 MatchesCopy.addDecl(Matches[I].second, Matches[I].first.getAccess()); 7826 7827 UnresolvedSetIterator Result = 7828 S.getMostSpecialized(MatchesCopy.begin(), MatchesCopy.end(), 7829 TPOC_Other, 0, SourceExpr->getLocStart(), 7830 S.PDiag(), 7831 S.PDiag(diag::err_addr_ovl_ambiguous) 7832 << Matches[0].second->getDeclName(), 7833 S.PDiag(diag::note_ovl_candidate) 7834 << (unsigned) oc_function_template, 7835 Complain); 7836 7837 if (Result != MatchesCopy.end()) { 7838 // Make it the first and only element 7839 Matches[0].first = Matches[Result - MatchesCopy.begin()].first; 7840 Matches[0].second = cast<FunctionDecl>(*Result); 7841 Matches.resize(1); 7842 } 7843 } 7844 7845 void EliminateAllTemplateMatches() { 7846 // [...] any function template specializations in the set are 7847 // eliminated if the set also contains a non-template function, [...] 7848 for (unsigned I = 0, N = Matches.size(); I != N; ) { 7849 if (Matches[I].second->getPrimaryTemplate() == 0) 7850 ++I; 7851 else { 7852 Matches[I] = Matches[--N]; 7853 Matches.set_size(N); 7854 } 7855 } 7856 } 7857 7858public: 7859 void ComplainNoMatchesFound() const { 7860 assert(Matches.empty()); 7861 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_no_viable) 7862 << OvlExpr->getName() << TargetFunctionType 7863 << OvlExpr->getSourceRange(); 7864 S.NoteAllOverloadCandidates(OvlExpr); 7865 } 7866 7867 bool IsInvalidFormOfPointerToMemberFunction() const { 7868 return TargetTypeIsNonStaticMemberFunction && 7869 !OvlExprInfo.HasFormOfMemberPointer; 7870 } 7871 7872 void ComplainIsInvalidFormOfPointerToMemberFunction() const { 7873 // TODO: Should we condition this on whether any functions might 7874 // have matched, or is it more appropriate to do that in callers? 7875 // TODO: a fixit wouldn't hurt. 7876 S.Diag(OvlExpr->getNameLoc(), diag::err_addr_ovl_no_qualifier) 7877 << TargetType << OvlExpr->getSourceRange(); 7878 } 7879 7880 void ComplainOfInvalidConversion() const { 7881 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_not_func_ptrref) 7882 << OvlExpr->getName() << TargetType; 7883 } 7884 7885 void ComplainMultipleMatchesFound() const { 7886 assert(Matches.size() > 1); 7887 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_ambiguous) 7888 << OvlExpr->getName() 7889 << OvlExpr->getSourceRange(); 7890 S.NoteAllOverloadCandidates(OvlExpr); 7891 } 7892 7893 int getNumMatches() const { return Matches.size(); } 7894 7895 FunctionDecl* getMatchingFunctionDecl() const { 7896 if (Matches.size() != 1) return 0; 7897 return Matches[0].second; 7898 } 7899 7900 const DeclAccessPair* getMatchingFunctionAccessPair() const { 7901 if (Matches.size() != 1) return 0; 7902 return &Matches[0].first; 7903 } 7904}; 7905 7906/// ResolveAddressOfOverloadedFunction - Try to resolve the address of 7907/// an overloaded function (C++ [over.over]), where @p From is an 7908/// expression with overloaded function type and @p ToType is the type 7909/// we're trying to resolve to. For example: 7910/// 7911/// @code 7912/// int f(double); 7913/// int f(int); 7914/// 7915/// int (*pfd)(double) = f; // selects f(double) 7916/// @endcode 7917/// 7918/// This routine returns the resulting FunctionDecl if it could be 7919/// resolved, and NULL otherwise. When @p Complain is true, this 7920/// routine will emit diagnostics if there is an error. 7921FunctionDecl * 7922Sema::ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr, QualType TargetType, 7923 bool Complain, 7924 DeclAccessPair &FoundResult) { 7925 7926 assert(AddressOfExpr->getType() == Context.OverloadTy); 7927 7928 AddressOfFunctionResolver Resolver(*this, AddressOfExpr, TargetType, Complain); 7929 int NumMatches = Resolver.getNumMatches(); 7930 FunctionDecl* Fn = 0; 7931 if ( NumMatches == 0 && Complain) { 7932 if (Resolver.IsInvalidFormOfPointerToMemberFunction()) 7933 Resolver.ComplainIsInvalidFormOfPointerToMemberFunction(); 7934 else 7935 Resolver.ComplainNoMatchesFound(); 7936 } 7937 else if (NumMatches > 1 && Complain) 7938 Resolver.ComplainMultipleMatchesFound(); 7939 else if (NumMatches == 1) { 7940 Fn = Resolver.getMatchingFunctionDecl(); 7941 assert(Fn); 7942 FoundResult = *Resolver.getMatchingFunctionAccessPair(); 7943 MarkDeclarationReferenced(AddressOfExpr->getLocStart(), Fn); 7944 if (Complain) 7945 CheckAddressOfMemberAccess(AddressOfExpr, FoundResult); 7946 } 7947 7948 return Fn; 7949} 7950 7951/// \brief Given an expression that refers to an overloaded function, try to 7952/// resolve that overloaded function expression down to a single function. 7953/// 7954/// This routine can only resolve template-ids that refer to a single function 7955/// template, where that template-id refers to a single template whose template 7956/// arguments are either provided by the template-id or have defaults, 7957/// as described in C++0x [temp.arg.explicit]p3. 7958FunctionDecl * 7959Sema::ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl, 7960 bool Complain, 7961 DeclAccessPair *FoundResult) { 7962 // C++ [over.over]p1: 7963 // [...] [Note: any redundant set of parentheses surrounding the 7964 // overloaded function name is ignored (5.1). ] 7965 // C++ [over.over]p1: 7966 // [...] The overloaded function name can be preceded by the & 7967 // operator. 7968 7969 // If we didn't actually find any template-ids, we're done. 7970 if (!ovl->hasExplicitTemplateArgs()) 7971 return 0; 7972 7973 TemplateArgumentListInfo ExplicitTemplateArgs; 7974 ovl->getExplicitTemplateArgs().copyInto(ExplicitTemplateArgs); 7975 7976 // Look through all of the overloaded functions, searching for one 7977 // whose type matches exactly. 7978 FunctionDecl *Matched = 0; 7979 for (UnresolvedSetIterator I = ovl->decls_begin(), 7980 E = ovl->decls_end(); I != E; ++I) { 7981 // C++0x [temp.arg.explicit]p3: 7982 // [...] In contexts where deduction is done and fails, or in contexts 7983 // where deduction is not done, if a template argument list is 7984 // specified and it, along with any default template arguments, 7985 // identifies a single function template specialization, then the 7986 // template-id is an lvalue for the function template specialization. 7987 FunctionTemplateDecl *FunctionTemplate 7988 = cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()); 7989 7990 // C++ [over.over]p2: 7991 // If the name is a function template, template argument deduction is 7992 // done (14.8.2.2), and if the argument deduction succeeds, the 7993 // resulting template argument list is used to generate a single 7994 // function template specialization, which is added to the set of 7995 // overloaded functions considered. 7996 FunctionDecl *Specialization = 0; 7997 TemplateDeductionInfo Info(Context, ovl->getNameLoc()); 7998 if (TemplateDeductionResult Result 7999 = DeduceTemplateArguments(FunctionTemplate, &ExplicitTemplateArgs, 8000 Specialization, Info)) { 8001 // FIXME: make a note of the failed deduction for diagnostics. 8002 (void)Result; 8003 continue; 8004 } 8005 8006 assert(Specialization && "no specialization and no error?"); 8007 8008 // Multiple matches; we can't resolve to a single declaration. 8009 if (Matched) { 8010 if (Complain) { 8011 Diag(ovl->getExprLoc(), diag::err_addr_ovl_ambiguous) 8012 << ovl->getName(); 8013 NoteAllOverloadCandidates(ovl); 8014 } 8015 return 0; 8016 } 8017 8018 Matched = Specialization; 8019 if (FoundResult) *FoundResult = I.getPair(); 8020 } 8021 8022 return Matched; 8023} 8024 8025 8026 8027 8028// Resolve and fix an overloaded expression that 8029// can be resolved because it identifies a single function 8030// template specialization 8031// Last three arguments should only be supplied if Complain = true 8032ExprResult Sema::ResolveAndFixSingleFunctionTemplateSpecialization( 8033 Expr *SrcExpr, bool doFunctionPointerConverion, bool complain, 8034 const SourceRange& OpRangeForComplaining, 8035 QualType DestTypeForComplaining, 8036 unsigned DiagIDForComplaining) { 8037 assert(SrcExpr->getType() == Context.OverloadTy); 8038 8039 OverloadExpr::FindResult ovl = OverloadExpr::find(SrcExpr); 8040 8041 DeclAccessPair found; 8042 ExprResult SingleFunctionExpression; 8043 if (FunctionDecl *fn = ResolveSingleFunctionTemplateSpecialization( 8044 ovl.Expression, /*complain*/ false, &found)) { 8045 if (DiagnoseUseOfDecl(fn, SrcExpr->getSourceRange().getBegin())) 8046 return ExprError(); 8047 8048 // It is only correct to resolve to an instance method if we're 8049 // resolving a form that's permitted to be a pointer to member. 8050 // Otherwise we'll end up making a bound member expression, which 8051 // is illegal in all the contexts we resolve like this. 8052 if (!ovl.HasFormOfMemberPointer && 8053 isa<CXXMethodDecl>(fn) && 8054 cast<CXXMethodDecl>(fn)->isInstance()) { 8055 if (complain) { 8056 Diag(ovl.Expression->getExprLoc(), 8057 diag::err_invalid_use_of_bound_member_func) 8058 << ovl.Expression->getSourceRange(); 8059 // TODO: I believe we only end up here if there's a mix of 8060 // static and non-static candidates (otherwise the expression 8061 // would have 'bound member' type, not 'overload' type). 8062 // Ideally we would note which candidate was chosen and why 8063 // the static candidates were rejected. 8064 } 8065 8066 return ExprError(); 8067 } 8068 8069 // Fix the expresion to refer to 'fn'. 8070 SingleFunctionExpression = 8071 Owned(FixOverloadedFunctionReference(SrcExpr, found, fn)); 8072 8073 // If desired, do function-to-pointer decay. 8074 if (doFunctionPointerConverion) 8075 SingleFunctionExpression = 8076 DefaultFunctionArrayLvalueConversion(SingleFunctionExpression.take()); 8077 } 8078 8079 if (!SingleFunctionExpression.isUsable()) { 8080 if (complain) { 8081 Diag(OpRangeForComplaining.getBegin(), DiagIDForComplaining) 8082 << ovl.Expression->getName() 8083 << DestTypeForComplaining 8084 << OpRangeForComplaining 8085 << ovl.Expression->getQualifierLoc().getSourceRange(); 8086 NoteAllOverloadCandidates(SrcExpr); 8087 } 8088 return ExprError(); 8089 } 8090 8091 return SingleFunctionExpression; 8092} 8093 8094/// \brief Add a single candidate to the overload set. 8095static void AddOverloadedCallCandidate(Sema &S, 8096 DeclAccessPair FoundDecl, 8097 TemplateArgumentListInfo *ExplicitTemplateArgs, 8098 Expr **Args, unsigned NumArgs, 8099 OverloadCandidateSet &CandidateSet, 8100 bool PartialOverloading, 8101 bool KnownValid) { 8102 NamedDecl *Callee = FoundDecl.getDecl(); 8103 if (isa<UsingShadowDecl>(Callee)) 8104 Callee = cast<UsingShadowDecl>(Callee)->getTargetDecl(); 8105 8106 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(Callee)) { 8107 if (ExplicitTemplateArgs) { 8108 assert(!KnownValid && "Explicit template arguments?"); 8109 return; 8110 } 8111 S.AddOverloadCandidate(Func, FoundDecl, Args, NumArgs, CandidateSet, 8112 false, PartialOverloading); 8113 return; 8114 } 8115 8116 if (FunctionTemplateDecl *FuncTemplate 8117 = dyn_cast<FunctionTemplateDecl>(Callee)) { 8118 S.AddTemplateOverloadCandidate(FuncTemplate, FoundDecl, 8119 ExplicitTemplateArgs, 8120 Args, NumArgs, CandidateSet); 8121 return; 8122 } 8123 8124 assert(!KnownValid && "unhandled case in overloaded call candidate"); 8125} 8126 8127/// \brief Add the overload candidates named by callee and/or found by argument 8128/// dependent lookup to the given overload set. 8129void Sema::AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE, 8130 Expr **Args, unsigned NumArgs, 8131 OverloadCandidateSet &CandidateSet, 8132 bool PartialOverloading) { 8133 8134#ifndef NDEBUG 8135 // Verify that ArgumentDependentLookup is consistent with the rules 8136 // in C++0x [basic.lookup.argdep]p3: 8137 // 8138 // Let X be the lookup set produced by unqualified lookup (3.4.1) 8139 // and let Y be the lookup set produced by argument dependent 8140 // lookup (defined as follows). If X contains 8141 // 8142 // -- a declaration of a class member, or 8143 // 8144 // -- a block-scope function declaration that is not a 8145 // using-declaration, or 8146 // 8147 // -- a declaration that is neither a function or a function 8148 // template 8149 // 8150 // then Y is empty. 8151 8152 if (ULE->requiresADL()) { 8153 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 8154 E = ULE->decls_end(); I != E; ++I) { 8155 assert(!(*I)->getDeclContext()->isRecord()); 8156 assert(isa<UsingShadowDecl>(*I) || 8157 !(*I)->getDeclContext()->isFunctionOrMethod()); 8158 assert((*I)->getUnderlyingDecl()->isFunctionOrFunctionTemplate()); 8159 } 8160 } 8161#endif 8162 8163 // It would be nice to avoid this copy. 8164 TemplateArgumentListInfo TABuffer; 8165 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 8166 if (ULE->hasExplicitTemplateArgs()) { 8167 ULE->copyTemplateArgumentsInto(TABuffer); 8168 ExplicitTemplateArgs = &TABuffer; 8169 } 8170 8171 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 8172 E = ULE->decls_end(); I != E; ++I) 8173 AddOverloadedCallCandidate(*this, I.getPair(), ExplicitTemplateArgs, 8174 Args, NumArgs, CandidateSet, 8175 PartialOverloading, /*KnownValid*/ true); 8176 8177 if (ULE->requiresADL()) 8178 AddArgumentDependentLookupCandidates(ULE->getName(), /*Operator*/ false, 8179 Args, NumArgs, 8180 ExplicitTemplateArgs, 8181 CandidateSet, 8182 PartialOverloading, 8183 ULE->isStdAssociatedNamespace()); 8184} 8185 8186/// Attempt to recover from an ill-formed use of a non-dependent name in a 8187/// template, where the non-dependent name was declared after the template 8188/// was defined. This is common in code written for a compilers which do not 8189/// correctly implement two-stage name lookup. 8190/// 8191/// Returns true if a viable candidate was found and a diagnostic was issued. 8192static bool 8193DiagnoseTwoPhaseLookup(Sema &SemaRef, SourceLocation FnLoc, 8194 const CXXScopeSpec &SS, LookupResult &R, 8195 TemplateArgumentListInfo *ExplicitTemplateArgs, 8196 Expr **Args, unsigned NumArgs) { 8197 if (SemaRef.ActiveTemplateInstantiations.empty() || !SS.isEmpty()) 8198 return false; 8199 8200 for (DeclContext *DC = SemaRef.CurContext; DC; DC = DC->getParent()) { 8201 SemaRef.LookupQualifiedName(R, DC); 8202 8203 if (!R.empty()) { 8204 R.suppressDiagnostics(); 8205 8206 if (isa<CXXRecordDecl>(DC)) { 8207 // Don't diagnose names we find in classes; we get much better 8208 // diagnostics for these from DiagnoseEmptyLookup. 8209 R.clear(); 8210 return false; 8211 } 8212 8213 OverloadCandidateSet Candidates(FnLoc); 8214 for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I) 8215 AddOverloadedCallCandidate(SemaRef, I.getPair(), 8216 ExplicitTemplateArgs, Args, NumArgs, 8217 Candidates, false, /*KnownValid*/ false); 8218 8219 OverloadCandidateSet::iterator Best; 8220 if (Candidates.BestViableFunction(SemaRef, FnLoc, Best) != OR_Success) { 8221 // No viable functions. Don't bother the user with notes for functions 8222 // which don't work and shouldn't be found anyway. 8223 R.clear(); 8224 return false; 8225 } 8226 8227 // Find the namespaces where ADL would have looked, and suggest 8228 // declaring the function there instead. 8229 Sema::AssociatedNamespaceSet AssociatedNamespaces; 8230 Sema::AssociatedClassSet AssociatedClasses; 8231 SemaRef.FindAssociatedClassesAndNamespaces(Args, NumArgs, 8232 AssociatedNamespaces, 8233 AssociatedClasses); 8234 // Never suggest declaring a function within namespace 'std'. 8235 Sema::AssociatedNamespaceSet SuggestedNamespaces; 8236 if (DeclContext *Std = SemaRef.getStdNamespace()) { 8237 for (Sema::AssociatedNamespaceSet::iterator 8238 it = AssociatedNamespaces.begin(), 8239 end = AssociatedNamespaces.end(); it != end; ++it) { 8240 if (!Std->Encloses(*it)) 8241 SuggestedNamespaces.insert(*it); 8242 } 8243 } else { 8244 // Lacking the 'std::' namespace, use all of the associated namespaces. 8245 SuggestedNamespaces = AssociatedNamespaces; 8246 } 8247 8248 SemaRef.Diag(R.getNameLoc(), diag::err_not_found_by_two_phase_lookup) 8249 << R.getLookupName(); 8250 if (SuggestedNamespaces.empty()) { 8251 SemaRef.Diag(Best->Function->getLocation(), 8252 diag::note_not_found_by_two_phase_lookup) 8253 << R.getLookupName() << 0; 8254 } else if (SuggestedNamespaces.size() == 1) { 8255 SemaRef.Diag(Best->Function->getLocation(), 8256 diag::note_not_found_by_two_phase_lookup) 8257 << R.getLookupName() << 1 << *SuggestedNamespaces.begin(); 8258 } else { 8259 // FIXME: It would be useful to list the associated namespaces here, 8260 // but the diagnostics infrastructure doesn't provide a way to produce 8261 // a localized representation of a list of items. 8262 SemaRef.Diag(Best->Function->getLocation(), 8263 diag::note_not_found_by_two_phase_lookup) 8264 << R.getLookupName() << 2; 8265 } 8266 8267 // Try to recover by calling this function. 8268 return true; 8269 } 8270 8271 R.clear(); 8272 } 8273 8274 return false; 8275} 8276 8277/// Attempt to recover from ill-formed use of a non-dependent operator in a 8278/// template, where the non-dependent operator was declared after the template 8279/// was defined. 8280/// 8281/// Returns true if a viable candidate was found and a diagnostic was issued. 8282static bool 8283DiagnoseTwoPhaseOperatorLookup(Sema &SemaRef, OverloadedOperatorKind Op, 8284 SourceLocation OpLoc, 8285 Expr **Args, unsigned NumArgs) { 8286 DeclarationName OpName = 8287 SemaRef.Context.DeclarationNames.getCXXOperatorName(Op); 8288 LookupResult R(SemaRef, OpName, OpLoc, Sema::LookupOperatorName); 8289 return DiagnoseTwoPhaseLookup(SemaRef, OpLoc, CXXScopeSpec(), R, 8290 /*ExplicitTemplateArgs=*/0, Args, NumArgs); 8291} 8292 8293/// Attempts to recover from a call where no functions were found. 8294/// 8295/// Returns true if new candidates were found. 8296static ExprResult 8297BuildRecoveryCallExpr(Sema &SemaRef, Scope *S, Expr *Fn, 8298 UnresolvedLookupExpr *ULE, 8299 SourceLocation LParenLoc, 8300 Expr **Args, unsigned NumArgs, 8301 SourceLocation RParenLoc, 8302 bool EmptyLookup) { 8303 8304 CXXScopeSpec SS; 8305 SS.Adopt(ULE->getQualifierLoc()); 8306 8307 TemplateArgumentListInfo TABuffer; 8308 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 8309 if (ULE->hasExplicitTemplateArgs()) { 8310 ULE->copyTemplateArgumentsInto(TABuffer); 8311 ExplicitTemplateArgs = &TABuffer; 8312 } 8313 8314 LookupResult R(SemaRef, ULE->getName(), ULE->getNameLoc(), 8315 Sema::LookupOrdinaryName); 8316 if (!DiagnoseTwoPhaseLookup(SemaRef, Fn->getExprLoc(), SS, R, 8317 ExplicitTemplateArgs, Args, NumArgs) && 8318 (!EmptyLookup || 8319 SemaRef.DiagnoseEmptyLookup(S, SS, R, Sema::CTC_Expression, 8320 ExplicitTemplateArgs, Args, NumArgs))) 8321 return ExprError(); 8322 8323 assert(!R.empty() && "lookup results empty despite recovery"); 8324 8325 // Build an implicit member call if appropriate. Just drop the 8326 // casts and such from the call, we don't really care. 8327 ExprResult NewFn = ExprError(); 8328 if ((*R.begin())->isCXXClassMember()) 8329 NewFn = SemaRef.BuildPossibleImplicitMemberExpr(SS, R, 8330 ExplicitTemplateArgs); 8331 else if (ExplicitTemplateArgs) 8332 NewFn = SemaRef.BuildTemplateIdExpr(SS, R, false, *ExplicitTemplateArgs); 8333 else 8334 NewFn = SemaRef.BuildDeclarationNameExpr(SS, R, false); 8335 8336 if (NewFn.isInvalid()) 8337 return ExprError(); 8338 8339 // This shouldn't cause an infinite loop because we're giving it 8340 // an expression with viable lookup results, which should never 8341 // end up here. 8342 return SemaRef.ActOnCallExpr(/*Scope*/ 0, NewFn.take(), LParenLoc, 8343 MultiExprArg(Args, NumArgs), RParenLoc); 8344} 8345 8346/// ResolveOverloadedCallFn - Given the call expression that calls Fn 8347/// (which eventually refers to the declaration Func) and the call 8348/// arguments Args/NumArgs, attempt to resolve the function call down 8349/// to a specific function. If overload resolution succeeds, returns 8350/// the function declaration produced by overload 8351/// resolution. Otherwise, emits diagnostics, deletes all of the 8352/// arguments and Fn, and returns NULL. 8353ExprResult 8354Sema::BuildOverloadedCallExpr(Scope *S, Expr *Fn, UnresolvedLookupExpr *ULE, 8355 SourceLocation LParenLoc, 8356 Expr **Args, unsigned NumArgs, 8357 SourceLocation RParenLoc, 8358 Expr *ExecConfig) { 8359#ifndef NDEBUG 8360 if (ULE->requiresADL()) { 8361 // To do ADL, we must have found an unqualified name. 8362 assert(!ULE->getQualifier() && "qualified name with ADL"); 8363 8364 // We don't perform ADL for implicit declarations of builtins. 8365 // Verify that this was correctly set up. 8366 FunctionDecl *F; 8367 if (ULE->decls_begin() + 1 == ULE->decls_end() && 8368 (F = dyn_cast<FunctionDecl>(*ULE->decls_begin())) && 8369 F->getBuiltinID() && F->isImplicit()) 8370 llvm_unreachable("performing ADL for builtin"); 8371 8372 // We don't perform ADL in C. 8373 assert(getLangOptions().CPlusPlus && "ADL enabled in C"); 8374 } else 8375 assert(!ULE->isStdAssociatedNamespace() && 8376 "std is associated namespace but not doing ADL"); 8377#endif 8378 8379 OverloadCandidateSet CandidateSet(Fn->getExprLoc()); 8380 8381 // Add the functions denoted by the callee to the set of candidate 8382 // functions, including those from argument-dependent lookup. 8383 AddOverloadedCallCandidates(ULE, Args, NumArgs, CandidateSet); 8384 8385 // If we found nothing, try to recover. 8386 // BuildRecoveryCallExpr diagnoses the error itself, so we just bail 8387 // out if it fails. 8388 if (CandidateSet.empty()) { 8389 // In Microsoft mode, if we are inside a template class member function then 8390 // create a type dependent CallExpr. The goal is to postpone name lookup 8391 // to instantiation time to be able to search into type dependent base 8392 // classes. 8393 if (getLangOptions().MicrosoftExt && CurContext->isDependentContext() && 8394 isa<CXXMethodDecl>(CurContext)) { 8395 CallExpr *CE = new (Context) CallExpr(Context, Fn, Args, NumArgs, 8396 Context.DependentTy, VK_RValue, 8397 RParenLoc); 8398 CE->setTypeDependent(true); 8399 return Owned(CE); 8400 } 8401 return BuildRecoveryCallExpr(*this, S, Fn, ULE, LParenLoc, Args, NumArgs, 8402 RParenLoc, /*EmptyLookup=*/true); 8403 } 8404 8405 OverloadCandidateSet::iterator Best; 8406 switch (CandidateSet.BestViableFunction(*this, Fn->getLocStart(), Best)) { 8407 case OR_Success: { 8408 FunctionDecl *FDecl = Best->Function; 8409 MarkDeclarationReferenced(Fn->getExprLoc(), FDecl); 8410 CheckUnresolvedLookupAccess(ULE, Best->FoundDecl); 8411 DiagnoseUseOfDecl(FDecl? FDecl : Best->FoundDecl.getDecl(), 8412 ULE->getNameLoc()); 8413 Fn = FixOverloadedFunctionReference(Fn, Best->FoundDecl, FDecl); 8414 return BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, NumArgs, RParenLoc, 8415 ExecConfig); 8416 } 8417 8418 case OR_No_Viable_Function: { 8419 // Try to recover by looking for viable functions which the user might 8420 // have meant to call. 8421 ExprResult Recovery = BuildRecoveryCallExpr(*this, S, Fn, ULE, LParenLoc, 8422 Args, NumArgs, RParenLoc, 8423 /*EmptyLookup=*/false); 8424 if (!Recovery.isInvalid()) 8425 return Recovery; 8426 8427 Diag(Fn->getSourceRange().getBegin(), 8428 diag::err_ovl_no_viable_function_in_call) 8429 << ULE->getName() << Fn->getSourceRange(); 8430 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8431 break; 8432 } 8433 8434 case OR_Ambiguous: 8435 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_ambiguous_call) 8436 << ULE->getName() << Fn->getSourceRange(); 8437 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 8438 break; 8439 8440 case OR_Deleted: 8441 { 8442 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_deleted_call) 8443 << Best->Function->isDeleted() 8444 << ULE->getName() 8445 << getDeletedOrUnavailableSuffix(Best->Function) 8446 << Fn->getSourceRange(); 8447 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8448 } 8449 break; 8450 } 8451 8452 // Overload resolution failed. 8453 return ExprError(); 8454} 8455 8456static bool IsOverloaded(const UnresolvedSetImpl &Functions) { 8457 return Functions.size() > 1 || 8458 (Functions.size() == 1 && isa<FunctionTemplateDecl>(*Functions.begin())); 8459} 8460 8461/// \brief Create a unary operation that may resolve to an overloaded 8462/// operator. 8463/// 8464/// \param OpLoc The location of the operator itself (e.g., '*'). 8465/// 8466/// \param OpcIn The UnaryOperator::Opcode that describes this 8467/// operator. 8468/// 8469/// \param Functions The set of non-member functions that will be 8470/// considered by overload resolution. The caller needs to build this 8471/// set based on the context using, e.g., 8472/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 8473/// set should not contain any member functions; those will be added 8474/// by CreateOverloadedUnaryOp(). 8475/// 8476/// \param input The input argument. 8477ExprResult 8478Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, unsigned OpcIn, 8479 const UnresolvedSetImpl &Fns, 8480 Expr *Input) { 8481 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 8482 8483 OverloadedOperatorKind Op = UnaryOperator::getOverloadedOperator(Opc); 8484 assert(Op != OO_None && "Invalid opcode for overloaded unary operator"); 8485 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 8486 // TODO: provide better source location info. 8487 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 8488 8489 if (Input->getObjectKind() == OK_ObjCProperty) { 8490 ExprResult Result = ConvertPropertyForRValue(Input); 8491 if (Result.isInvalid()) 8492 return ExprError(); 8493 Input = Result.take(); 8494 } 8495 8496 Expr *Args[2] = { Input, 0 }; 8497 unsigned NumArgs = 1; 8498 8499 // For post-increment and post-decrement, add the implicit '0' as 8500 // the second argument, so that we know this is a post-increment or 8501 // post-decrement. 8502 if (Opc == UO_PostInc || Opc == UO_PostDec) { 8503 llvm::APSInt Zero(Context.getTypeSize(Context.IntTy), false); 8504 Args[1] = IntegerLiteral::Create(Context, Zero, Context.IntTy, 8505 SourceLocation()); 8506 NumArgs = 2; 8507 } 8508 8509 if (Input->isTypeDependent()) { 8510 if (Fns.empty()) 8511 return Owned(new (Context) UnaryOperator(Input, 8512 Opc, 8513 Context.DependentTy, 8514 VK_RValue, OK_Ordinary, 8515 OpLoc)); 8516 8517 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8518 UnresolvedLookupExpr *Fn 8519 = UnresolvedLookupExpr::Create(Context, NamingClass, 8520 NestedNameSpecifierLoc(), OpNameInfo, 8521 /*ADL*/ true, IsOverloaded(Fns), 8522 Fns.begin(), Fns.end()); 8523 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 8524 &Args[0], NumArgs, 8525 Context.DependentTy, 8526 VK_RValue, 8527 OpLoc)); 8528 } 8529 8530 // Build an empty overload set. 8531 OverloadCandidateSet CandidateSet(OpLoc); 8532 8533 // Add the candidates from the given function set. 8534 AddFunctionCandidates(Fns, &Args[0], NumArgs, CandidateSet, false); 8535 8536 // Add operator candidates that are member functions. 8537 AddMemberOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 8538 8539 // Add candidates from ADL. 8540 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 8541 Args, NumArgs, 8542 /*ExplicitTemplateArgs*/ 0, 8543 CandidateSet); 8544 8545 // Add builtin operator candidates. 8546 AddBuiltinOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 8547 8548 // Perform overload resolution. 8549 OverloadCandidateSet::iterator Best; 8550 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8551 case OR_Success: { 8552 // We found a built-in operator or an overloaded operator. 8553 FunctionDecl *FnDecl = Best->Function; 8554 8555 if (FnDecl) { 8556 // We matched an overloaded operator. Build a call to that 8557 // operator. 8558 8559 MarkDeclarationReferenced(OpLoc, FnDecl); 8560 8561 // Convert the arguments. 8562 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 8563 CheckMemberOperatorAccess(OpLoc, Args[0], 0, Best->FoundDecl); 8564 8565 ExprResult InputRes = 8566 PerformObjectArgumentInitialization(Input, /*Qualifier=*/0, 8567 Best->FoundDecl, Method); 8568 if (InputRes.isInvalid()) 8569 return ExprError(); 8570 Input = InputRes.take(); 8571 } else { 8572 // Convert the arguments. 8573 ExprResult InputInit 8574 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 8575 Context, 8576 FnDecl->getParamDecl(0)), 8577 SourceLocation(), 8578 Input); 8579 if (InputInit.isInvalid()) 8580 return ExprError(); 8581 Input = InputInit.take(); 8582 } 8583 8584 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 8585 8586 // Determine the result type. 8587 QualType ResultTy = FnDecl->getResultType(); 8588 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8589 ResultTy = ResultTy.getNonLValueExprType(Context); 8590 8591 // Build the actual expression node. 8592 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl); 8593 if (FnExpr.isInvalid()) 8594 return ExprError(); 8595 8596 Args[0] = Input; 8597 CallExpr *TheCall = 8598 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 8599 Args, NumArgs, ResultTy, VK, OpLoc); 8600 8601 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 8602 FnDecl)) 8603 return ExprError(); 8604 8605 return MaybeBindToTemporary(TheCall); 8606 } else { 8607 // We matched a built-in operator. Convert the arguments, then 8608 // break out so that we will build the appropriate built-in 8609 // operator node. 8610 ExprResult InputRes = 8611 PerformImplicitConversion(Input, Best->BuiltinTypes.ParamTypes[0], 8612 Best->Conversions[0], AA_Passing); 8613 if (InputRes.isInvalid()) 8614 return ExprError(); 8615 Input = InputRes.take(); 8616 break; 8617 } 8618 } 8619 8620 case OR_No_Viable_Function: 8621 // This is an erroneous use of an operator which can be overloaded by 8622 // a non-member function. Check for non-member operators which were 8623 // defined too late to be candidates. 8624 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, Args, NumArgs)) 8625 // FIXME: Recover by calling the found function. 8626 return ExprError(); 8627 8628 // No viable function; fall through to handling this as a 8629 // built-in operator, which will produce an error message for us. 8630 break; 8631 8632 case OR_Ambiguous: 8633 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 8634 << UnaryOperator::getOpcodeStr(Opc) 8635 << Input->getType() 8636 << Input->getSourceRange(); 8637 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs, 8638 UnaryOperator::getOpcodeStr(Opc), OpLoc); 8639 return ExprError(); 8640 8641 case OR_Deleted: 8642 Diag(OpLoc, diag::err_ovl_deleted_oper) 8643 << Best->Function->isDeleted() 8644 << UnaryOperator::getOpcodeStr(Opc) 8645 << getDeletedOrUnavailableSuffix(Best->Function) 8646 << Input->getSourceRange(); 8647 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs, 8648 UnaryOperator::getOpcodeStr(Opc), OpLoc); 8649 return ExprError(); 8650 } 8651 8652 // Either we found no viable overloaded operator or we matched a 8653 // built-in operator. In either case, fall through to trying to 8654 // build a built-in operation. 8655 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8656} 8657 8658/// \brief Create a binary operation that may resolve to an overloaded 8659/// operator. 8660/// 8661/// \param OpLoc The location of the operator itself (e.g., '+'). 8662/// 8663/// \param OpcIn The BinaryOperator::Opcode that describes this 8664/// operator. 8665/// 8666/// \param Functions The set of non-member functions that will be 8667/// considered by overload resolution. The caller needs to build this 8668/// set based on the context using, e.g., 8669/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 8670/// set should not contain any member functions; those will be added 8671/// by CreateOverloadedBinOp(). 8672/// 8673/// \param LHS Left-hand argument. 8674/// \param RHS Right-hand argument. 8675ExprResult 8676Sema::CreateOverloadedBinOp(SourceLocation OpLoc, 8677 unsigned OpcIn, 8678 const UnresolvedSetImpl &Fns, 8679 Expr *LHS, Expr *RHS) { 8680 Expr *Args[2] = { LHS, RHS }; 8681 LHS=RHS=0; //Please use only Args instead of LHS/RHS couple 8682 8683 BinaryOperator::Opcode Opc = static_cast<BinaryOperator::Opcode>(OpcIn); 8684 OverloadedOperatorKind Op = BinaryOperator::getOverloadedOperator(Opc); 8685 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 8686 8687 // If either side is type-dependent, create an appropriate dependent 8688 // expression. 8689 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 8690 if (Fns.empty()) { 8691 // If there are no functions to store, just build a dependent 8692 // BinaryOperator or CompoundAssignment. 8693 if (Opc <= BO_Assign || Opc > BO_OrAssign) 8694 return Owned(new (Context) BinaryOperator(Args[0], Args[1], Opc, 8695 Context.DependentTy, 8696 VK_RValue, OK_Ordinary, 8697 OpLoc)); 8698 8699 return Owned(new (Context) CompoundAssignOperator(Args[0], Args[1], Opc, 8700 Context.DependentTy, 8701 VK_LValue, 8702 OK_Ordinary, 8703 Context.DependentTy, 8704 Context.DependentTy, 8705 OpLoc)); 8706 } 8707 8708 // FIXME: save results of ADL from here? 8709 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8710 // TODO: provide better source location info in DNLoc component. 8711 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 8712 UnresolvedLookupExpr *Fn 8713 = UnresolvedLookupExpr::Create(Context, NamingClass, 8714 NestedNameSpecifierLoc(), OpNameInfo, 8715 /*ADL*/ true, IsOverloaded(Fns), 8716 Fns.begin(), Fns.end()); 8717 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 8718 Args, 2, 8719 Context.DependentTy, 8720 VK_RValue, 8721 OpLoc)); 8722 } 8723 8724 // Always do property rvalue conversions on the RHS. 8725 if (Args[1]->getObjectKind() == OK_ObjCProperty) { 8726 ExprResult Result = ConvertPropertyForRValue(Args[1]); 8727 if (Result.isInvalid()) 8728 return ExprError(); 8729 Args[1] = Result.take(); 8730 } 8731 8732 // The LHS is more complicated. 8733 if (Args[0]->getObjectKind() == OK_ObjCProperty) { 8734 8735 // There's a tension for assignment operators between primitive 8736 // property assignment and the overloaded operators. 8737 if (BinaryOperator::isAssignmentOp(Opc)) { 8738 const ObjCPropertyRefExpr *PRE = LHS->getObjCProperty(); 8739 8740 // Is the property "logically" settable? 8741 bool Settable = (PRE->isExplicitProperty() || 8742 PRE->getImplicitPropertySetter()); 8743 8744 // To avoid gratuitously inventing semantics, use the primitive 8745 // unless it isn't. Thoughts in case we ever really care: 8746 // - If the property isn't logically settable, we have to 8747 // load and hope. 8748 // - If the property is settable and this is simple assignment, 8749 // we really should use the primitive. 8750 // - If the property is settable, then we could try overloading 8751 // on a generic lvalue of the appropriate type; if it works 8752 // out to a builtin candidate, we would do that same operation 8753 // on the property, and otherwise just error. 8754 if (Settable) 8755 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8756 } 8757 8758 ExprResult Result = ConvertPropertyForRValue(Args[0]); 8759 if (Result.isInvalid()) 8760 return ExprError(); 8761 Args[0] = Result.take(); 8762 } 8763 8764 // If this is the assignment operator, we only perform overload resolution 8765 // if the left-hand side is a class or enumeration type. This is actually 8766 // a hack. The standard requires that we do overload resolution between the 8767 // various built-in candidates, but as DR507 points out, this can lead to 8768 // problems. So we do it this way, which pretty much follows what GCC does. 8769 // Note that we go the traditional code path for compound assignment forms. 8770 if (Opc == BO_Assign && !Args[0]->getType()->isOverloadableType()) 8771 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8772 8773 // If this is the .* operator, which is not overloadable, just 8774 // create a built-in binary operator. 8775 if (Opc == BO_PtrMemD) 8776 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8777 8778 // Build an empty overload set. 8779 OverloadCandidateSet CandidateSet(OpLoc); 8780 8781 // Add the candidates from the given function set. 8782 AddFunctionCandidates(Fns, Args, 2, CandidateSet, false); 8783 8784 // Add operator candidates that are member functions. 8785 AddMemberOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 8786 8787 // Add candidates from ADL. 8788 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 8789 Args, 2, 8790 /*ExplicitTemplateArgs*/ 0, 8791 CandidateSet); 8792 8793 // Add builtin operator candidates. 8794 AddBuiltinOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 8795 8796 // Perform overload resolution. 8797 OverloadCandidateSet::iterator Best; 8798 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8799 case OR_Success: { 8800 // We found a built-in operator or an overloaded operator. 8801 FunctionDecl *FnDecl = Best->Function; 8802 8803 if (FnDecl) { 8804 // We matched an overloaded operator. Build a call to that 8805 // operator. 8806 8807 MarkDeclarationReferenced(OpLoc, FnDecl); 8808 8809 // Convert the arguments. 8810 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 8811 // Best->Access is only meaningful for class members. 8812 CheckMemberOperatorAccess(OpLoc, Args[0], Args[1], Best->FoundDecl); 8813 8814 ExprResult Arg1 = 8815 PerformCopyInitialization( 8816 InitializedEntity::InitializeParameter(Context, 8817 FnDecl->getParamDecl(0)), 8818 SourceLocation(), Owned(Args[1])); 8819 if (Arg1.isInvalid()) 8820 return ExprError(); 8821 8822 ExprResult Arg0 = 8823 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 8824 Best->FoundDecl, Method); 8825 if (Arg0.isInvalid()) 8826 return ExprError(); 8827 Args[0] = Arg0.takeAs<Expr>(); 8828 Args[1] = RHS = Arg1.takeAs<Expr>(); 8829 } else { 8830 // Convert the arguments. 8831 ExprResult Arg0 = PerformCopyInitialization( 8832 InitializedEntity::InitializeParameter(Context, 8833 FnDecl->getParamDecl(0)), 8834 SourceLocation(), Owned(Args[0])); 8835 if (Arg0.isInvalid()) 8836 return ExprError(); 8837 8838 ExprResult Arg1 = 8839 PerformCopyInitialization( 8840 InitializedEntity::InitializeParameter(Context, 8841 FnDecl->getParamDecl(1)), 8842 SourceLocation(), Owned(Args[1])); 8843 if (Arg1.isInvalid()) 8844 return ExprError(); 8845 Args[0] = LHS = Arg0.takeAs<Expr>(); 8846 Args[1] = RHS = Arg1.takeAs<Expr>(); 8847 } 8848 8849 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 8850 8851 // Determine the result type. 8852 QualType ResultTy = FnDecl->getResultType(); 8853 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8854 ResultTy = ResultTy.getNonLValueExprType(Context); 8855 8856 // Build the actual expression node. 8857 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, OpLoc); 8858 if (FnExpr.isInvalid()) 8859 return ExprError(); 8860 8861 CXXOperatorCallExpr *TheCall = 8862 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 8863 Args, 2, ResultTy, VK, OpLoc); 8864 8865 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 8866 FnDecl)) 8867 return ExprError(); 8868 8869 return MaybeBindToTemporary(TheCall); 8870 } else { 8871 // We matched a built-in operator. Convert the arguments, then 8872 // break out so that we will build the appropriate built-in 8873 // operator node. 8874 ExprResult ArgsRes0 = 8875 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 8876 Best->Conversions[0], AA_Passing); 8877 if (ArgsRes0.isInvalid()) 8878 return ExprError(); 8879 Args[0] = ArgsRes0.take(); 8880 8881 ExprResult ArgsRes1 = 8882 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 8883 Best->Conversions[1], AA_Passing); 8884 if (ArgsRes1.isInvalid()) 8885 return ExprError(); 8886 Args[1] = ArgsRes1.take(); 8887 break; 8888 } 8889 } 8890 8891 case OR_No_Viable_Function: { 8892 // C++ [over.match.oper]p9: 8893 // If the operator is the operator , [...] and there are no 8894 // viable functions, then the operator is assumed to be the 8895 // built-in operator and interpreted according to clause 5. 8896 if (Opc == BO_Comma) 8897 break; 8898 8899 // For class as left operand for assignment or compound assigment 8900 // operator do not fall through to handling in built-in, but report that 8901 // no overloaded assignment operator found 8902 ExprResult Result = ExprError(); 8903 if (Args[0]->getType()->isRecordType() && 8904 Opc >= BO_Assign && Opc <= BO_OrAssign) { 8905 Diag(OpLoc, diag::err_ovl_no_viable_oper) 8906 << BinaryOperator::getOpcodeStr(Opc) 8907 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8908 } else { 8909 // This is an erroneous use of an operator which can be overloaded by 8910 // a non-member function. Check for non-member operators which were 8911 // defined too late to be candidates. 8912 if (DiagnoseTwoPhaseOperatorLookup(*this, Op, OpLoc, Args, 2)) 8913 // FIXME: Recover by calling the found function. 8914 return ExprError(); 8915 8916 // No viable function; try to create a built-in operation, which will 8917 // produce an error. Then, show the non-viable candidates. 8918 Result = CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8919 } 8920 assert(Result.isInvalid() && 8921 "C++ binary operator overloading is missing candidates!"); 8922 if (Result.isInvalid()) 8923 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8924 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8925 return move(Result); 8926 } 8927 8928 case OR_Ambiguous: 8929 Diag(OpLoc, diag::err_ovl_ambiguous_oper_binary) 8930 << BinaryOperator::getOpcodeStr(Opc) 8931 << Args[0]->getType() << Args[1]->getType() 8932 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8933 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 8934 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8935 return ExprError(); 8936 8937 case OR_Deleted: 8938 Diag(OpLoc, diag::err_ovl_deleted_oper) 8939 << Best->Function->isDeleted() 8940 << BinaryOperator::getOpcodeStr(Opc) 8941 << getDeletedOrUnavailableSuffix(Best->Function) 8942 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8943 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8944 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8945 return ExprError(); 8946 } 8947 8948 // We matched a built-in operator; build it. 8949 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8950} 8951 8952ExprResult 8953Sema::CreateOverloadedArraySubscriptExpr(SourceLocation LLoc, 8954 SourceLocation RLoc, 8955 Expr *Base, Expr *Idx) { 8956 Expr *Args[2] = { Base, Idx }; 8957 DeclarationName OpName = 8958 Context.DeclarationNames.getCXXOperatorName(OO_Subscript); 8959 8960 // If either side is type-dependent, create an appropriate dependent 8961 // expression. 8962 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 8963 8964 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8965 // CHECKME: no 'operator' keyword? 8966 DeclarationNameInfo OpNameInfo(OpName, LLoc); 8967 OpNameInfo.setCXXOperatorNameRange(SourceRange(LLoc, RLoc)); 8968 UnresolvedLookupExpr *Fn 8969 = UnresolvedLookupExpr::Create(Context, NamingClass, 8970 NestedNameSpecifierLoc(), OpNameInfo, 8971 /*ADL*/ true, /*Overloaded*/ false, 8972 UnresolvedSetIterator(), 8973 UnresolvedSetIterator()); 8974 // Can't add any actual overloads yet 8975 8976 return Owned(new (Context) CXXOperatorCallExpr(Context, OO_Subscript, Fn, 8977 Args, 2, 8978 Context.DependentTy, 8979 VK_RValue, 8980 RLoc)); 8981 } 8982 8983 if (Args[0]->getObjectKind() == OK_ObjCProperty) { 8984 ExprResult Result = ConvertPropertyForRValue(Args[0]); 8985 if (Result.isInvalid()) 8986 return ExprError(); 8987 Args[0] = Result.take(); 8988 } 8989 if (Args[1]->getObjectKind() == OK_ObjCProperty) { 8990 ExprResult Result = ConvertPropertyForRValue(Args[1]); 8991 if (Result.isInvalid()) 8992 return ExprError(); 8993 Args[1] = Result.take(); 8994 } 8995 8996 // Build an empty overload set. 8997 OverloadCandidateSet CandidateSet(LLoc); 8998 8999 // Subscript can only be overloaded as a member function. 9000 9001 // Add operator candidates that are member functions. 9002 AddMemberOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 9003 9004 // Add builtin operator candidates. 9005 AddBuiltinOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 9006 9007 // Perform overload resolution. 9008 OverloadCandidateSet::iterator Best; 9009 switch (CandidateSet.BestViableFunction(*this, LLoc, Best)) { 9010 case OR_Success: { 9011 // We found a built-in operator or an overloaded operator. 9012 FunctionDecl *FnDecl = Best->Function; 9013 9014 if (FnDecl) { 9015 // We matched an overloaded operator. Build a call to that 9016 // operator. 9017 9018 MarkDeclarationReferenced(LLoc, FnDecl); 9019 9020 CheckMemberOperatorAccess(LLoc, Args[0], Args[1], Best->FoundDecl); 9021 DiagnoseUseOfDecl(Best->FoundDecl, LLoc); 9022 9023 // Convert the arguments. 9024 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 9025 ExprResult Arg0 = 9026 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 9027 Best->FoundDecl, Method); 9028 if (Arg0.isInvalid()) 9029 return ExprError(); 9030 Args[0] = Arg0.take(); 9031 9032 // Convert the arguments. 9033 ExprResult InputInit 9034 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 9035 Context, 9036 FnDecl->getParamDecl(0)), 9037 SourceLocation(), 9038 Owned(Args[1])); 9039 if (InputInit.isInvalid()) 9040 return ExprError(); 9041 9042 Args[1] = InputInit.takeAs<Expr>(); 9043 9044 // Determine the result type 9045 QualType ResultTy = FnDecl->getResultType(); 9046 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9047 ResultTy = ResultTy.getNonLValueExprType(Context); 9048 9049 // Build the actual expression node. 9050 DeclarationNameLoc LocInfo; 9051 LocInfo.CXXOperatorName.BeginOpNameLoc = LLoc.getRawEncoding(); 9052 LocInfo.CXXOperatorName.EndOpNameLoc = RLoc.getRawEncoding(); 9053 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, LLoc, LocInfo); 9054 if (FnExpr.isInvalid()) 9055 return ExprError(); 9056 9057 CXXOperatorCallExpr *TheCall = 9058 new (Context) CXXOperatorCallExpr(Context, OO_Subscript, 9059 FnExpr.take(), Args, 2, 9060 ResultTy, VK, RLoc); 9061 9062 if (CheckCallReturnType(FnDecl->getResultType(), LLoc, TheCall, 9063 FnDecl)) 9064 return ExprError(); 9065 9066 return MaybeBindToTemporary(TheCall); 9067 } else { 9068 // We matched a built-in operator. Convert the arguments, then 9069 // break out so that we will build the appropriate built-in 9070 // operator node. 9071 ExprResult ArgsRes0 = 9072 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 9073 Best->Conversions[0], AA_Passing); 9074 if (ArgsRes0.isInvalid()) 9075 return ExprError(); 9076 Args[0] = ArgsRes0.take(); 9077 9078 ExprResult ArgsRes1 = 9079 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 9080 Best->Conversions[1], AA_Passing); 9081 if (ArgsRes1.isInvalid()) 9082 return ExprError(); 9083 Args[1] = ArgsRes1.take(); 9084 9085 break; 9086 } 9087 } 9088 9089 case OR_No_Viable_Function: { 9090 if (CandidateSet.empty()) 9091 Diag(LLoc, diag::err_ovl_no_oper) 9092 << Args[0]->getType() << /*subscript*/ 0 9093 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9094 else 9095 Diag(LLoc, diag::err_ovl_no_viable_subscript) 9096 << Args[0]->getType() 9097 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9098 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 9099 "[]", LLoc); 9100 return ExprError(); 9101 } 9102 9103 case OR_Ambiguous: 9104 Diag(LLoc, diag::err_ovl_ambiguous_oper_binary) 9105 << "[]" 9106 << Args[0]->getType() << Args[1]->getType() 9107 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9108 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 9109 "[]", LLoc); 9110 return ExprError(); 9111 9112 case OR_Deleted: 9113 Diag(LLoc, diag::err_ovl_deleted_oper) 9114 << Best->Function->isDeleted() << "[]" 9115 << getDeletedOrUnavailableSuffix(Best->Function) 9116 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 9117 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 9118 "[]", LLoc); 9119 return ExprError(); 9120 } 9121 9122 // We matched a built-in operator; build it. 9123 return CreateBuiltinArraySubscriptExpr(Args[0], LLoc, Args[1], RLoc); 9124} 9125 9126/// BuildCallToMemberFunction - Build a call to a member 9127/// function. MemExpr is the expression that refers to the member 9128/// function (and includes the object parameter), Args/NumArgs are the 9129/// arguments to the function call (not including the object 9130/// parameter). The caller needs to validate that the member 9131/// expression refers to a non-static member function or an overloaded 9132/// member function. 9133ExprResult 9134Sema::BuildCallToMemberFunction(Scope *S, Expr *MemExprE, 9135 SourceLocation LParenLoc, Expr **Args, 9136 unsigned NumArgs, SourceLocation RParenLoc) { 9137 assert(MemExprE->getType() == Context.BoundMemberTy || 9138 MemExprE->getType() == Context.OverloadTy); 9139 9140 // Dig out the member expression. This holds both the object 9141 // argument and the member function we're referring to. 9142 Expr *NakedMemExpr = MemExprE->IgnoreParens(); 9143 9144 // Determine whether this is a call to a pointer-to-member function. 9145 if (BinaryOperator *op = dyn_cast<BinaryOperator>(NakedMemExpr)) { 9146 assert(op->getType() == Context.BoundMemberTy); 9147 assert(op->getOpcode() == BO_PtrMemD || op->getOpcode() == BO_PtrMemI); 9148 9149 QualType fnType = 9150 op->getRHS()->getType()->castAs<MemberPointerType>()->getPointeeType(); 9151 9152 const FunctionProtoType *proto = fnType->castAs<FunctionProtoType>(); 9153 QualType resultType = proto->getCallResultType(Context); 9154 ExprValueKind valueKind = Expr::getValueKindForType(proto->getResultType()); 9155 9156 // Check that the object type isn't more qualified than the 9157 // member function we're calling. 9158 Qualifiers funcQuals = Qualifiers::fromCVRMask(proto->getTypeQuals()); 9159 9160 QualType objectType = op->getLHS()->getType(); 9161 if (op->getOpcode() == BO_PtrMemI) 9162 objectType = objectType->castAs<PointerType>()->getPointeeType(); 9163 Qualifiers objectQuals = objectType.getQualifiers(); 9164 9165 Qualifiers difference = objectQuals - funcQuals; 9166 difference.removeObjCGCAttr(); 9167 difference.removeAddressSpace(); 9168 if (difference) { 9169 std::string qualsString = difference.getAsString(); 9170 Diag(LParenLoc, diag::err_pointer_to_member_call_drops_quals) 9171 << fnType.getUnqualifiedType() 9172 << qualsString 9173 << (qualsString.find(' ') == std::string::npos ? 1 : 2); 9174 } 9175 9176 CXXMemberCallExpr *call 9177 = new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 9178 resultType, valueKind, RParenLoc); 9179 9180 if (CheckCallReturnType(proto->getResultType(), 9181 op->getRHS()->getSourceRange().getBegin(), 9182 call, 0)) 9183 return ExprError(); 9184 9185 if (ConvertArgumentsForCall(call, op, 0, proto, Args, NumArgs, RParenLoc)) 9186 return ExprError(); 9187 9188 return MaybeBindToTemporary(call); 9189 } 9190 9191 MemberExpr *MemExpr; 9192 CXXMethodDecl *Method = 0; 9193 DeclAccessPair FoundDecl = DeclAccessPair::make(0, AS_public); 9194 NestedNameSpecifier *Qualifier = 0; 9195 if (isa<MemberExpr>(NakedMemExpr)) { 9196 MemExpr = cast<MemberExpr>(NakedMemExpr); 9197 Method = cast<CXXMethodDecl>(MemExpr->getMemberDecl()); 9198 FoundDecl = MemExpr->getFoundDecl(); 9199 Qualifier = MemExpr->getQualifier(); 9200 } else { 9201 UnresolvedMemberExpr *UnresExpr = cast<UnresolvedMemberExpr>(NakedMemExpr); 9202 Qualifier = UnresExpr->getQualifier(); 9203 9204 QualType ObjectType = UnresExpr->getBaseType(); 9205 Expr::Classification ObjectClassification 9206 = UnresExpr->isArrow()? Expr::Classification::makeSimpleLValue() 9207 : UnresExpr->getBase()->Classify(Context); 9208 9209 // Add overload candidates 9210 OverloadCandidateSet CandidateSet(UnresExpr->getMemberLoc()); 9211 9212 // FIXME: avoid copy. 9213 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9214 if (UnresExpr->hasExplicitTemplateArgs()) { 9215 UnresExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 9216 TemplateArgs = &TemplateArgsBuffer; 9217 } 9218 9219 for (UnresolvedMemberExpr::decls_iterator I = UnresExpr->decls_begin(), 9220 E = UnresExpr->decls_end(); I != E; ++I) { 9221 9222 NamedDecl *Func = *I; 9223 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(Func->getDeclContext()); 9224 if (isa<UsingShadowDecl>(Func)) 9225 Func = cast<UsingShadowDecl>(Func)->getTargetDecl(); 9226 9227 9228 // Microsoft supports direct constructor calls. 9229 if (getLangOptions().MicrosoftExt && isa<CXXConstructorDecl>(Func)) { 9230 AddOverloadCandidate(cast<CXXConstructorDecl>(Func), I.getPair(), Args, NumArgs, 9231 CandidateSet); 9232 } else if ((Method = dyn_cast<CXXMethodDecl>(Func))) { 9233 // If explicit template arguments were provided, we can't call a 9234 // non-template member function. 9235 if (TemplateArgs) 9236 continue; 9237 9238 AddMethodCandidate(Method, I.getPair(), ActingDC, ObjectType, 9239 ObjectClassification, 9240 Args, NumArgs, CandidateSet, 9241 /*SuppressUserConversions=*/false); 9242 } else { 9243 AddMethodTemplateCandidate(cast<FunctionTemplateDecl>(Func), 9244 I.getPair(), ActingDC, TemplateArgs, 9245 ObjectType, ObjectClassification, 9246 Args, NumArgs, CandidateSet, 9247 /*SuppressUsedConversions=*/false); 9248 } 9249 } 9250 9251 DeclarationName DeclName = UnresExpr->getMemberName(); 9252 9253 OverloadCandidateSet::iterator Best; 9254 switch (CandidateSet.BestViableFunction(*this, UnresExpr->getLocStart(), 9255 Best)) { 9256 case OR_Success: 9257 Method = cast<CXXMethodDecl>(Best->Function); 9258 MarkDeclarationReferenced(UnresExpr->getMemberLoc(), Method); 9259 FoundDecl = Best->FoundDecl; 9260 CheckUnresolvedMemberAccess(UnresExpr, Best->FoundDecl); 9261 DiagnoseUseOfDecl(Best->FoundDecl, UnresExpr->getNameLoc()); 9262 break; 9263 9264 case OR_No_Viable_Function: 9265 Diag(UnresExpr->getMemberLoc(), 9266 diag::err_ovl_no_viable_member_function_in_call) 9267 << DeclName << MemExprE->getSourceRange(); 9268 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9269 // FIXME: Leaking incoming expressions! 9270 return ExprError(); 9271 9272 case OR_Ambiguous: 9273 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_ambiguous_member_call) 9274 << DeclName << MemExprE->getSourceRange(); 9275 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9276 // FIXME: Leaking incoming expressions! 9277 return ExprError(); 9278 9279 case OR_Deleted: 9280 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_deleted_member_call) 9281 << Best->Function->isDeleted() 9282 << DeclName 9283 << getDeletedOrUnavailableSuffix(Best->Function) 9284 << MemExprE->getSourceRange(); 9285 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9286 // FIXME: Leaking incoming expressions! 9287 return ExprError(); 9288 } 9289 9290 MemExprE = FixOverloadedFunctionReference(MemExprE, FoundDecl, Method); 9291 9292 // If overload resolution picked a static member, build a 9293 // non-member call based on that function. 9294 if (Method->isStatic()) { 9295 return BuildResolvedCallExpr(MemExprE, Method, LParenLoc, 9296 Args, NumArgs, RParenLoc); 9297 } 9298 9299 MemExpr = cast<MemberExpr>(MemExprE->IgnoreParens()); 9300 } 9301 9302 QualType ResultType = Method->getResultType(); 9303 ExprValueKind VK = Expr::getValueKindForType(ResultType); 9304 ResultType = ResultType.getNonLValueExprType(Context); 9305 9306 assert(Method && "Member call to something that isn't a method?"); 9307 CXXMemberCallExpr *TheCall = 9308 new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 9309 ResultType, VK, RParenLoc); 9310 9311 // Check for a valid return type. 9312 if (CheckCallReturnType(Method->getResultType(), MemExpr->getMemberLoc(), 9313 TheCall, Method)) 9314 return ExprError(); 9315 9316 // Convert the object argument (for a non-static member function call). 9317 // We only need to do this if there was actually an overload; otherwise 9318 // it was done at lookup. 9319 if (!Method->isStatic()) { 9320 ExprResult ObjectArg = 9321 PerformObjectArgumentInitialization(MemExpr->getBase(), Qualifier, 9322 FoundDecl, Method); 9323 if (ObjectArg.isInvalid()) 9324 return ExprError(); 9325 MemExpr->setBase(ObjectArg.take()); 9326 } 9327 9328 // Convert the rest of the arguments 9329 const FunctionProtoType *Proto = 9330 Method->getType()->getAs<FunctionProtoType>(); 9331 if (ConvertArgumentsForCall(TheCall, MemExpr, Method, Proto, Args, NumArgs, 9332 RParenLoc)) 9333 return ExprError(); 9334 9335 if (CheckFunctionCall(Method, TheCall)) 9336 return ExprError(); 9337 9338 if ((isa<CXXConstructorDecl>(CurContext) || 9339 isa<CXXDestructorDecl>(CurContext)) && 9340 TheCall->getMethodDecl()->isPure()) { 9341 const CXXMethodDecl *MD = TheCall->getMethodDecl(); 9342 9343 if (isa<CXXThisExpr>(MemExpr->getBase()->IgnoreParenCasts())) { 9344 Diag(MemExpr->getLocStart(), 9345 diag::warn_call_to_pure_virtual_member_function_from_ctor_dtor) 9346 << MD->getDeclName() << isa<CXXDestructorDecl>(CurContext) 9347 << MD->getParent()->getDeclName(); 9348 9349 Diag(MD->getLocStart(), diag::note_previous_decl) << MD->getDeclName(); 9350 } 9351 } 9352 return MaybeBindToTemporary(TheCall); 9353} 9354 9355/// BuildCallToObjectOfClassType - Build a call to an object of class 9356/// type (C++ [over.call.object]), which can end up invoking an 9357/// overloaded function call operator (@c operator()) or performing a 9358/// user-defined conversion on the object argument. 9359ExprResult 9360Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj, 9361 SourceLocation LParenLoc, 9362 Expr **Args, unsigned NumArgs, 9363 SourceLocation RParenLoc) { 9364 ExprResult Object = Owned(Obj); 9365 if (Object.get()->getObjectKind() == OK_ObjCProperty) { 9366 Object = ConvertPropertyForRValue(Object.take()); 9367 if (Object.isInvalid()) 9368 return ExprError(); 9369 } 9370 9371 assert(Object.get()->getType()->isRecordType() && "Requires object type argument"); 9372 const RecordType *Record = Object.get()->getType()->getAs<RecordType>(); 9373 9374 // C++ [over.call.object]p1: 9375 // If the primary-expression E in the function call syntax 9376 // evaluates to a class object of type "cv T", then the set of 9377 // candidate functions includes at least the function call 9378 // operators of T. The function call operators of T are obtained by 9379 // ordinary lookup of the name operator() in the context of 9380 // (E).operator(). 9381 OverloadCandidateSet CandidateSet(LParenLoc); 9382 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(OO_Call); 9383 9384 if (RequireCompleteType(LParenLoc, Object.get()->getType(), 9385 PDiag(diag::err_incomplete_object_call) 9386 << Object.get()->getSourceRange())) 9387 return true; 9388 9389 LookupResult R(*this, OpName, LParenLoc, LookupOrdinaryName); 9390 LookupQualifiedName(R, Record->getDecl()); 9391 R.suppressDiagnostics(); 9392 9393 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 9394 Oper != OperEnd; ++Oper) { 9395 AddMethodCandidate(Oper.getPair(), Object.get()->getType(), 9396 Object.get()->Classify(Context), Args, NumArgs, CandidateSet, 9397 /*SuppressUserConversions=*/ false); 9398 } 9399 9400 // C++ [over.call.object]p2: 9401 // In addition, for each (non-explicit in C++0x) conversion function 9402 // declared in T of the form 9403 // 9404 // operator conversion-type-id () cv-qualifier; 9405 // 9406 // where cv-qualifier is the same cv-qualification as, or a 9407 // greater cv-qualification than, cv, and where conversion-type-id 9408 // denotes the type "pointer to function of (P1,...,Pn) returning 9409 // R", or the type "reference to pointer to function of 9410 // (P1,...,Pn) returning R", or the type "reference to function 9411 // of (P1,...,Pn) returning R", a surrogate call function [...] 9412 // is also considered as a candidate function. Similarly, 9413 // surrogate call functions are added to the set of candidate 9414 // functions for each conversion function declared in an 9415 // accessible base class provided the function is not hidden 9416 // within T by another intervening declaration. 9417 const UnresolvedSetImpl *Conversions 9418 = cast<CXXRecordDecl>(Record->getDecl())->getVisibleConversionFunctions(); 9419 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 9420 E = Conversions->end(); I != E; ++I) { 9421 NamedDecl *D = *I; 9422 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 9423 if (isa<UsingShadowDecl>(D)) 9424 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 9425 9426 // Skip over templated conversion functions; they aren't 9427 // surrogates. 9428 if (isa<FunctionTemplateDecl>(D)) 9429 continue; 9430 9431 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 9432 if (!Conv->isExplicit()) { 9433 // Strip the reference type (if any) and then the pointer type (if 9434 // any) to get down to what might be a function type. 9435 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 9436 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 9437 ConvType = ConvPtrType->getPointeeType(); 9438 9439 if (const FunctionProtoType *Proto = ConvType->getAs<FunctionProtoType>()) 9440 { 9441 AddSurrogateCandidate(Conv, I.getPair(), ActingContext, Proto, 9442 Object.get(), Args, NumArgs, CandidateSet); 9443 } 9444 } 9445 } 9446 9447 // Perform overload resolution. 9448 OverloadCandidateSet::iterator Best; 9449 switch (CandidateSet.BestViableFunction(*this, Object.get()->getLocStart(), 9450 Best)) { 9451 case OR_Success: 9452 // Overload resolution succeeded; we'll build the appropriate call 9453 // below. 9454 break; 9455 9456 case OR_No_Viable_Function: 9457 if (CandidateSet.empty()) 9458 Diag(Object.get()->getSourceRange().getBegin(), diag::err_ovl_no_oper) 9459 << Object.get()->getType() << /*call*/ 1 9460 << Object.get()->getSourceRange(); 9461 else 9462 Diag(Object.get()->getSourceRange().getBegin(), 9463 diag::err_ovl_no_viable_object_call) 9464 << Object.get()->getType() << Object.get()->getSourceRange(); 9465 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9466 break; 9467 9468 case OR_Ambiguous: 9469 Diag(Object.get()->getSourceRange().getBegin(), 9470 diag::err_ovl_ambiguous_object_call) 9471 << Object.get()->getType() << Object.get()->getSourceRange(); 9472 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 9473 break; 9474 9475 case OR_Deleted: 9476 Diag(Object.get()->getSourceRange().getBegin(), 9477 diag::err_ovl_deleted_object_call) 9478 << Best->Function->isDeleted() 9479 << Object.get()->getType() 9480 << getDeletedOrUnavailableSuffix(Best->Function) 9481 << Object.get()->getSourceRange(); 9482 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 9483 break; 9484 } 9485 9486 if (Best == CandidateSet.end()) 9487 return true; 9488 9489 if (Best->Function == 0) { 9490 // Since there is no function declaration, this is one of the 9491 // surrogate candidates. Dig out the conversion function. 9492 CXXConversionDecl *Conv 9493 = cast<CXXConversionDecl>( 9494 Best->Conversions[0].UserDefined.ConversionFunction); 9495 9496 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 9497 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 9498 9499 // We selected one of the surrogate functions that converts the 9500 // object parameter to a function pointer. Perform the conversion 9501 // on the object argument, then let ActOnCallExpr finish the job. 9502 9503 // Create an implicit member expr to refer to the conversion operator. 9504 // and then call it. 9505 ExprResult Call = BuildCXXMemberCallExpr(Object.get(), Best->FoundDecl, Conv); 9506 if (Call.isInvalid()) 9507 return ExprError(); 9508 9509 return ActOnCallExpr(S, Call.get(), LParenLoc, MultiExprArg(Args, NumArgs), 9510 RParenLoc); 9511 } 9512 9513 MarkDeclarationReferenced(LParenLoc, Best->Function); 9514 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 9515 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 9516 9517 // We found an overloaded operator(). Build a CXXOperatorCallExpr 9518 // that calls this method, using Object for the implicit object 9519 // parameter and passing along the remaining arguments. 9520 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 9521 const FunctionProtoType *Proto = 9522 Method->getType()->getAs<FunctionProtoType>(); 9523 9524 unsigned NumArgsInProto = Proto->getNumArgs(); 9525 unsigned NumArgsToCheck = NumArgs; 9526 9527 // Build the full argument list for the method call (the 9528 // implicit object parameter is placed at the beginning of the 9529 // list). 9530 Expr **MethodArgs; 9531 if (NumArgs < NumArgsInProto) { 9532 NumArgsToCheck = NumArgsInProto; 9533 MethodArgs = new Expr*[NumArgsInProto + 1]; 9534 } else { 9535 MethodArgs = new Expr*[NumArgs + 1]; 9536 } 9537 MethodArgs[0] = Object.get(); 9538 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 9539 MethodArgs[ArgIdx + 1] = Args[ArgIdx]; 9540 9541 ExprResult NewFn = CreateFunctionRefExpr(*this, Method); 9542 if (NewFn.isInvalid()) 9543 return true; 9544 9545 // Once we've built TheCall, all of the expressions are properly 9546 // owned. 9547 QualType ResultTy = Method->getResultType(); 9548 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9549 ResultTy = ResultTy.getNonLValueExprType(Context); 9550 9551 CXXOperatorCallExpr *TheCall = 9552 new (Context) CXXOperatorCallExpr(Context, OO_Call, NewFn.take(), 9553 MethodArgs, NumArgs + 1, 9554 ResultTy, VK, RParenLoc); 9555 delete [] MethodArgs; 9556 9557 if (CheckCallReturnType(Method->getResultType(), LParenLoc, TheCall, 9558 Method)) 9559 return true; 9560 9561 // We may have default arguments. If so, we need to allocate more 9562 // slots in the call for them. 9563 if (NumArgs < NumArgsInProto) 9564 TheCall->setNumArgs(Context, NumArgsInProto + 1); 9565 else if (NumArgs > NumArgsInProto) 9566 NumArgsToCheck = NumArgsInProto; 9567 9568 bool IsError = false; 9569 9570 // Initialize the implicit object parameter. 9571 ExprResult ObjRes = 9572 PerformObjectArgumentInitialization(Object.get(), /*Qualifier=*/0, 9573 Best->FoundDecl, Method); 9574 if (ObjRes.isInvalid()) 9575 IsError = true; 9576 else 9577 Object = move(ObjRes); 9578 TheCall->setArg(0, Object.take()); 9579 9580 // Check the argument types. 9581 for (unsigned i = 0; i != NumArgsToCheck; i++) { 9582 Expr *Arg; 9583 if (i < NumArgs) { 9584 Arg = Args[i]; 9585 9586 // Pass the argument. 9587 9588 ExprResult InputInit 9589 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 9590 Context, 9591 Method->getParamDecl(i)), 9592 SourceLocation(), Arg); 9593 9594 IsError |= InputInit.isInvalid(); 9595 Arg = InputInit.takeAs<Expr>(); 9596 } else { 9597 ExprResult DefArg 9598 = BuildCXXDefaultArgExpr(LParenLoc, Method, Method->getParamDecl(i)); 9599 if (DefArg.isInvalid()) { 9600 IsError = true; 9601 break; 9602 } 9603 9604 Arg = DefArg.takeAs<Expr>(); 9605 } 9606 9607 TheCall->setArg(i + 1, Arg); 9608 } 9609 9610 // If this is a variadic call, handle args passed through "...". 9611 if (Proto->isVariadic()) { 9612 // Promote the arguments (C99 6.5.2.2p7). 9613 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 9614 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], VariadicMethod, 0); 9615 IsError |= Arg.isInvalid(); 9616 TheCall->setArg(i + 1, Arg.take()); 9617 } 9618 } 9619 9620 if (IsError) return true; 9621 9622 if (CheckFunctionCall(Method, TheCall)) 9623 return true; 9624 9625 return MaybeBindToTemporary(TheCall); 9626} 9627 9628/// BuildOverloadedArrowExpr - Build a call to an overloaded @c operator-> 9629/// (if one exists), where @c Base is an expression of class type and 9630/// @c Member is the name of the member we're trying to find. 9631ExprResult 9632Sema::BuildOverloadedArrowExpr(Scope *S, Expr *Base, SourceLocation OpLoc) { 9633 assert(Base->getType()->isRecordType() && 9634 "left-hand side must have class type"); 9635 9636 if (Base->getObjectKind() == OK_ObjCProperty) { 9637 ExprResult Result = ConvertPropertyForRValue(Base); 9638 if (Result.isInvalid()) 9639 return ExprError(); 9640 Base = Result.take(); 9641 } 9642 9643 SourceLocation Loc = Base->getExprLoc(); 9644 9645 // C++ [over.ref]p1: 9646 // 9647 // [...] An expression x->m is interpreted as (x.operator->())->m 9648 // for a class object x of type T if T::operator->() exists and if 9649 // the operator is selected as the best match function by the 9650 // overload resolution mechanism (13.3). 9651 DeclarationName OpName = 9652 Context.DeclarationNames.getCXXOperatorName(OO_Arrow); 9653 OverloadCandidateSet CandidateSet(Loc); 9654 const RecordType *BaseRecord = Base->getType()->getAs<RecordType>(); 9655 9656 if (RequireCompleteType(Loc, Base->getType(), 9657 PDiag(diag::err_typecheck_incomplete_tag) 9658 << Base->getSourceRange())) 9659 return ExprError(); 9660 9661 LookupResult R(*this, OpName, OpLoc, LookupOrdinaryName); 9662 LookupQualifiedName(R, BaseRecord->getDecl()); 9663 R.suppressDiagnostics(); 9664 9665 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 9666 Oper != OperEnd; ++Oper) { 9667 AddMethodCandidate(Oper.getPair(), Base->getType(), Base->Classify(Context), 9668 0, 0, CandidateSet, /*SuppressUserConversions=*/false); 9669 } 9670 9671 // Perform overload resolution. 9672 OverloadCandidateSet::iterator Best; 9673 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 9674 case OR_Success: 9675 // Overload resolution succeeded; we'll build the call below. 9676 break; 9677 9678 case OR_No_Viable_Function: 9679 if (CandidateSet.empty()) 9680 Diag(OpLoc, diag::err_typecheck_member_reference_arrow) 9681 << Base->getType() << Base->getSourceRange(); 9682 else 9683 Diag(OpLoc, diag::err_ovl_no_viable_oper) 9684 << "operator->" << Base->getSourceRange(); 9685 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 9686 return ExprError(); 9687 9688 case OR_Ambiguous: 9689 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 9690 << "->" << Base->getType() << Base->getSourceRange(); 9691 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, &Base, 1); 9692 return ExprError(); 9693 9694 case OR_Deleted: 9695 Diag(OpLoc, diag::err_ovl_deleted_oper) 9696 << Best->Function->isDeleted() 9697 << "->" 9698 << getDeletedOrUnavailableSuffix(Best->Function) 9699 << Base->getSourceRange(); 9700 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 9701 return ExprError(); 9702 } 9703 9704 MarkDeclarationReferenced(OpLoc, Best->Function); 9705 CheckMemberOperatorAccess(OpLoc, Base, 0, Best->FoundDecl); 9706 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 9707 9708 // Convert the object parameter. 9709 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 9710 ExprResult BaseResult = 9711 PerformObjectArgumentInitialization(Base, /*Qualifier=*/0, 9712 Best->FoundDecl, Method); 9713 if (BaseResult.isInvalid()) 9714 return ExprError(); 9715 Base = BaseResult.take(); 9716 9717 // Build the operator call. 9718 ExprResult FnExpr = CreateFunctionRefExpr(*this, Method); 9719 if (FnExpr.isInvalid()) 9720 return ExprError(); 9721 9722 QualType ResultTy = Method->getResultType(); 9723 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9724 ResultTy = ResultTy.getNonLValueExprType(Context); 9725 CXXOperatorCallExpr *TheCall = 9726 new (Context) CXXOperatorCallExpr(Context, OO_Arrow, FnExpr.take(), 9727 &Base, 1, ResultTy, VK, OpLoc); 9728 9729 if (CheckCallReturnType(Method->getResultType(), OpLoc, TheCall, 9730 Method)) 9731 return ExprError(); 9732 9733 return MaybeBindToTemporary(TheCall); 9734} 9735 9736/// FixOverloadedFunctionReference - E is an expression that refers to 9737/// a C++ overloaded function (possibly with some parentheses and 9738/// perhaps a '&' around it). We have resolved the overloaded function 9739/// to the function declaration Fn, so patch up the expression E to 9740/// refer (possibly indirectly) to Fn. Returns the new expr. 9741Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found, 9742 FunctionDecl *Fn) { 9743 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 9744 Expr *SubExpr = FixOverloadedFunctionReference(PE->getSubExpr(), 9745 Found, Fn); 9746 if (SubExpr == PE->getSubExpr()) 9747 return PE; 9748 9749 return new (Context) ParenExpr(PE->getLParen(), PE->getRParen(), SubExpr); 9750 } 9751 9752 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 9753 Expr *SubExpr = FixOverloadedFunctionReference(ICE->getSubExpr(), 9754 Found, Fn); 9755 assert(Context.hasSameType(ICE->getSubExpr()->getType(), 9756 SubExpr->getType()) && 9757 "Implicit cast type cannot be determined from overload"); 9758 assert(ICE->path_empty() && "fixing up hierarchy conversion?"); 9759 if (SubExpr == ICE->getSubExpr()) 9760 return ICE; 9761 9762 return ImplicitCastExpr::Create(Context, ICE->getType(), 9763 ICE->getCastKind(), 9764 SubExpr, 0, 9765 ICE->getValueKind()); 9766 } 9767 9768 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(E)) { 9769 assert(UnOp->getOpcode() == UO_AddrOf && 9770 "Can only take the address of an overloaded function"); 9771 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 9772 if (Method->isStatic()) { 9773 // Do nothing: static member functions aren't any different 9774 // from non-member functions. 9775 } else { 9776 // Fix the sub expression, which really has to be an 9777 // UnresolvedLookupExpr holding an overloaded member function 9778 // or template. 9779 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 9780 Found, Fn); 9781 if (SubExpr == UnOp->getSubExpr()) 9782 return UnOp; 9783 9784 assert(isa<DeclRefExpr>(SubExpr) 9785 && "fixed to something other than a decl ref"); 9786 assert(cast<DeclRefExpr>(SubExpr)->getQualifier() 9787 && "fixed to a member ref with no nested name qualifier"); 9788 9789 // We have taken the address of a pointer to member 9790 // function. Perform the computation here so that we get the 9791 // appropriate pointer to member type. 9792 QualType ClassType 9793 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 9794 QualType MemPtrType 9795 = Context.getMemberPointerType(Fn->getType(), ClassType.getTypePtr()); 9796 9797 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, MemPtrType, 9798 VK_RValue, OK_Ordinary, 9799 UnOp->getOperatorLoc()); 9800 } 9801 } 9802 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 9803 Found, Fn); 9804 if (SubExpr == UnOp->getSubExpr()) 9805 return UnOp; 9806 9807 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, 9808 Context.getPointerType(SubExpr->getType()), 9809 VK_RValue, OK_Ordinary, 9810 UnOp->getOperatorLoc()); 9811 } 9812 9813 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { 9814 // FIXME: avoid copy. 9815 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9816 if (ULE->hasExplicitTemplateArgs()) { 9817 ULE->copyTemplateArgumentsInto(TemplateArgsBuffer); 9818 TemplateArgs = &TemplateArgsBuffer; 9819 } 9820 9821 return DeclRefExpr::Create(Context, 9822 ULE->getQualifierLoc(), 9823 Fn, 9824 ULE->getNameLoc(), 9825 Fn->getType(), 9826 VK_LValue, 9827 Found.getDecl(), 9828 TemplateArgs); 9829 } 9830 9831 if (UnresolvedMemberExpr *MemExpr = dyn_cast<UnresolvedMemberExpr>(E)) { 9832 // FIXME: avoid copy. 9833 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9834 if (MemExpr->hasExplicitTemplateArgs()) { 9835 MemExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 9836 TemplateArgs = &TemplateArgsBuffer; 9837 } 9838 9839 Expr *Base; 9840 9841 // If we're filling in a static method where we used to have an 9842 // implicit member access, rewrite to a simple decl ref. 9843 if (MemExpr->isImplicitAccess()) { 9844 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 9845 return DeclRefExpr::Create(Context, 9846 MemExpr->getQualifierLoc(), 9847 Fn, 9848 MemExpr->getMemberLoc(), 9849 Fn->getType(), 9850 VK_LValue, 9851 Found.getDecl(), 9852 TemplateArgs); 9853 } else { 9854 SourceLocation Loc = MemExpr->getMemberLoc(); 9855 if (MemExpr->getQualifier()) 9856 Loc = MemExpr->getQualifierLoc().getBeginLoc(); 9857 Base = new (Context) CXXThisExpr(Loc, 9858 MemExpr->getBaseType(), 9859 /*isImplicit=*/true); 9860 } 9861 } else 9862 Base = MemExpr->getBase(); 9863 9864 ExprValueKind valueKind; 9865 QualType type; 9866 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 9867 valueKind = VK_LValue; 9868 type = Fn->getType(); 9869 } else { 9870 valueKind = VK_RValue; 9871 type = Context.BoundMemberTy; 9872 } 9873 9874 return MemberExpr::Create(Context, Base, 9875 MemExpr->isArrow(), 9876 MemExpr->getQualifierLoc(), 9877 Fn, 9878 Found, 9879 MemExpr->getMemberNameInfo(), 9880 TemplateArgs, 9881 type, valueKind, OK_Ordinary); 9882 } 9883 9884 llvm_unreachable("Invalid reference to overloaded function"); 9885 return E; 9886} 9887 9888ExprResult Sema::FixOverloadedFunctionReference(ExprResult E, 9889 DeclAccessPair Found, 9890 FunctionDecl *Fn) { 9891 return Owned(FixOverloadedFunctionReference((Expr *)E.get(), Found, Fn)); 9892} 9893 9894} // end namespace clang 9895