SemaOverload.cpp revision f5307514ee48978b5e17e42542e111afee4ce62b
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 ExprResult E = S.Owned(new (S.Context) DeclRefExpr(Fn, Fn->getType(), VK_LValue, Loc)); 43 E = S.DefaultFunctionArrayConversion(E.take()); 44 if (E.isInvalid()) 45 return ExprError(); 46 return move(E); 47} 48 49static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType, 50 bool InOverloadResolution, 51 StandardConversionSequence &SCS, 52 bool CStyle); 53 54static bool IsTransparentUnionStandardConversion(Sema &S, Expr* From, 55 QualType &ToType, 56 bool InOverloadResolution, 57 StandardConversionSequence &SCS, 58 bool CStyle); 59static OverloadingResult 60IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 61 UserDefinedConversionSequence& User, 62 OverloadCandidateSet& Conversions, 63 bool AllowExplicit); 64 65 66static ImplicitConversionSequence::CompareKind 67CompareStandardConversionSequences(Sema &S, 68 const StandardConversionSequence& SCS1, 69 const StandardConversionSequence& SCS2); 70 71static ImplicitConversionSequence::CompareKind 72CompareQualificationConversions(Sema &S, 73 const StandardConversionSequence& SCS1, 74 const StandardConversionSequence& SCS2); 75 76static ImplicitConversionSequence::CompareKind 77CompareDerivedToBaseConversions(Sema &S, 78 const StandardConversionSequence& SCS1, 79 const StandardConversionSequence& SCS2); 80 81 82 83/// GetConversionCategory - Retrieve the implicit conversion 84/// category corresponding to the given implicit conversion kind. 85ImplicitConversionCategory 86GetConversionCategory(ImplicitConversionKind Kind) { 87 static const ImplicitConversionCategory 88 Category[(int)ICK_Num_Conversion_Kinds] = { 89 ICC_Identity, 90 ICC_Lvalue_Transformation, 91 ICC_Lvalue_Transformation, 92 ICC_Lvalue_Transformation, 93 ICC_Identity, 94 ICC_Qualification_Adjustment, 95 ICC_Promotion, 96 ICC_Promotion, 97 ICC_Promotion, 98 ICC_Conversion, 99 ICC_Conversion, 100 ICC_Conversion, 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 }; 111 return Category[(int)Kind]; 112} 113 114/// GetConversionRank - Retrieve the implicit conversion rank 115/// corresponding to the given implicit conversion kind. 116ImplicitConversionRank GetConversionRank(ImplicitConversionKind Kind) { 117 static const ImplicitConversionRank 118 Rank[(int)ICK_Num_Conversion_Kinds] = { 119 ICR_Exact_Match, 120 ICR_Exact_Match, 121 ICR_Exact_Match, 122 ICR_Exact_Match, 123 ICR_Exact_Match, 124 ICR_Exact_Match, 125 ICR_Promotion, 126 ICR_Promotion, 127 ICR_Promotion, 128 ICR_Conversion, 129 ICR_Conversion, 130 ICR_Conversion, 131 ICR_Conversion, 132 ICR_Conversion, 133 ICR_Conversion, 134 ICR_Conversion, 135 ICR_Conversion, 136 ICR_Conversion, 137 ICR_Conversion, 138 ICR_Conversion, 139 ICR_Complex_Real_Conversion, 140 ICR_Conversion, 141 ICR_Conversion 142 }; 143 return Rank[(int)Kind]; 144} 145 146/// GetImplicitConversionName - Return the name of this kind of 147/// implicit conversion. 148const char* GetImplicitConversionName(ImplicitConversionKind Kind) { 149 static const char* const Name[(int)ICK_Num_Conversion_Kinds] = { 150 "No conversion", 151 "Lvalue-to-rvalue", 152 "Array-to-pointer", 153 "Function-to-pointer", 154 "Noreturn adjustment", 155 "Qualification", 156 "Integral promotion", 157 "Floating point promotion", 158 "Complex promotion", 159 "Integral conversion", 160 "Floating conversion", 161 "Complex conversion", 162 "Floating-integral conversion", 163 "Pointer conversion", 164 "Pointer-to-member conversion", 165 "Boolean conversion", 166 "Compatible-types conversion", 167 "Derived-to-base conversion", 168 "Vector conversion", 169 "Vector splat", 170 "Complex-real conversion", 171 "Block Pointer conversion", 172 "Transparent Union Conversion" 173 }; 174 return Name[Kind]; 175} 176 177/// StandardConversionSequence - Set the standard conversion 178/// sequence to the identity conversion. 179void StandardConversionSequence::setAsIdentityConversion() { 180 First = ICK_Identity; 181 Second = ICK_Identity; 182 Third = ICK_Identity; 183 DeprecatedStringLiteralToCharPtr = false; 184 ReferenceBinding = false; 185 DirectBinding = false; 186 IsLvalueReference = true; 187 BindsToFunctionLvalue = false; 188 BindsToRvalue = false; 189 BindsImplicitObjectArgumentWithoutRefQualifier = false; 190 CopyConstructor = 0; 191} 192 193/// getRank - Retrieve the rank of this standard conversion sequence 194/// (C++ 13.3.3.1.1p3). The rank is the largest rank of each of the 195/// implicit conversions. 196ImplicitConversionRank StandardConversionSequence::getRank() const { 197 ImplicitConversionRank Rank = ICR_Exact_Match; 198 if (GetConversionRank(First) > Rank) 199 Rank = GetConversionRank(First); 200 if (GetConversionRank(Second) > Rank) 201 Rank = GetConversionRank(Second); 202 if (GetConversionRank(Third) > Rank) 203 Rank = GetConversionRank(Third); 204 return Rank; 205} 206 207/// isPointerConversionToBool - Determines whether this conversion is 208/// a conversion of a pointer or pointer-to-member to bool. This is 209/// used as part of the ranking of standard conversion sequences 210/// (C++ 13.3.3.2p4). 211bool StandardConversionSequence::isPointerConversionToBool() const { 212 // Note that FromType has not necessarily been transformed by the 213 // array-to-pointer or function-to-pointer implicit conversions, so 214 // check for their presence as well as checking whether FromType is 215 // a pointer. 216 if (getToType(1)->isBooleanType() && 217 (getFromType()->isPointerType() || 218 getFromType()->isObjCObjectPointerType() || 219 getFromType()->isBlockPointerType() || 220 getFromType()->isNullPtrType() || 221 First == ICK_Array_To_Pointer || First == ICK_Function_To_Pointer)) 222 return true; 223 224 return false; 225} 226 227/// isPointerConversionToVoidPointer - Determines whether this 228/// conversion is a conversion of a pointer to a void pointer. This is 229/// used as part of the ranking of standard conversion sequences (C++ 230/// 13.3.3.2p4). 231bool 232StandardConversionSequence:: 233isPointerConversionToVoidPointer(ASTContext& Context) const { 234 QualType FromType = getFromType(); 235 QualType ToType = getToType(1); 236 237 // Note that FromType has not necessarily been transformed by the 238 // array-to-pointer implicit conversion, so check for its presence 239 // and redo the conversion to get a pointer. 240 if (First == ICK_Array_To_Pointer) 241 FromType = Context.getArrayDecayedType(FromType); 242 243 if (Second == ICK_Pointer_Conversion && FromType->isAnyPointerType()) 244 if (const PointerType* ToPtrType = ToType->getAs<PointerType>()) 245 return ToPtrType->getPointeeType()->isVoidType(); 246 247 return false; 248} 249 250/// DebugPrint - Print this standard conversion sequence to standard 251/// error. Useful for debugging overloading issues. 252void StandardConversionSequence::DebugPrint() const { 253 llvm::raw_ostream &OS = llvm::errs(); 254 bool PrintedSomething = false; 255 if (First != ICK_Identity) { 256 OS << GetImplicitConversionName(First); 257 PrintedSomething = true; 258 } 259 260 if (Second != ICK_Identity) { 261 if (PrintedSomething) { 262 OS << " -> "; 263 } 264 OS << GetImplicitConversionName(Second); 265 266 if (CopyConstructor) { 267 OS << " (by copy constructor)"; 268 } else if (DirectBinding) { 269 OS << " (direct reference binding)"; 270 } else if (ReferenceBinding) { 271 OS << " (reference binding)"; 272 } 273 PrintedSomething = true; 274 } 275 276 if (Third != ICK_Identity) { 277 if (PrintedSomething) { 278 OS << " -> "; 279 } 280 OS << GetImplicitConversionName(Third); 281 PrintedSomething = true; 282 } 283 284 if (!PrintedSomething) { 285 OS << "No conversions required"; 286 } 287} 288 289/// DebugPrint - Print this user-defined conversion sequence to standard 290/// error. Useful for debugging overloading issues. 291void UserDefinedConversionSequence::DebugPrint() const { 292 llvm::raw_ostream &OS = llvm::errs(); 293 if (Before.First || Before.Second || Before.Third) { 294 Before.DebugPrint(); 295 OS << " -> "; 296 } 297 OS << '\'' << ConversionFunction << '\''; 298 if (After.First || After.Second || After.Third) { 299 OS << " -> "; 300 After.DebugPrint(); 301 } 302} 303 304/// DebugPrint - Print this implicit conversion sequence to standard 305/// error. Useful for debugging overloading issues. 306void ImplicitConversionSequence::DebugPrint() const { 307 llvm::raw_ostream &OS = llvm::errs(); 308 switch (ConversionKind) { 309 case StandardConversion: 310 OS << "Standard conversion: "; 311 Standard.DebugPrint(); 312 break; 313 case UserDefinedConversion: 314 OS << "User-defined conversion: "; 315 UserDefined.DebugPrint(); 316 break; 317 case EllipsisConversion: 318 OS << "Ellipsis conversion"; 319 break; 320 case AmbiguousConversion: 321 OS << "Ambiguous conversion"; 322 break; 323 case BadConversion: 324 OS << "Bad conversion"; 325 break; 326 } 327 328 OS << "\n"; 329} 330 331void AmbiguousConversionSequence::construct() { 332 new (&conversions()) ConversionSet(); 333} 334 335void AmbiguousConversionSequence::destruct() { 336 conversions().~ConversionSet(); 337} 338 339void 340AmbiguousConversionSequence::copyFrom(const AmbiguousConversionSequence &O) { 341 FromTypePtr = O.FromTypePtr; 342 ToTypePtr = O.ToTypePtr; 343 new (&conversions()) ConversionSet(O.conversions()); 344} 345 346namespace { 347 // Structure used by OverloadCandidate::DeductionFailureInfo to store 348 // template parameter and template argument information. 349 struct DFIParamWithArguments { 350 TemplateParameter Param; 351 TemplateArgument FirstArg; 352 TemplateArgument SecondArg; 353 }; 354} 355 356/// \brief Convert from Sema's representation of template deduction information 357/// to the form used in overload-candidate information. 358OverloadCandidate::DeductionFailureInfo 359static MakeDeductionFailureInfo(ASTContext &Context, 360 Sema::TemplateDeductionResult TDK, 361 TemplateDeductionInfo &Info) { 362 OverloadCandidate::DeductionFailureInfo Result; 363 Result.Result = static_cast<unsigned>(TDK); 364 Result.Data = 0; 365 switch (TDK) { 366 case Sema::TDK_Success: 367 case Sema::TDK_InstantiationDepth: 368 case Sema::TDK_TooManyArguments: 369 case Sema::TDK_TooFewArguments: 370 break; 371 372 case Sema::TDK_Incomplete: 373 case Sema::TDK_InvalidExplicitArguments: 374 Result.Data = Info.Param.getOpaqueValue(); 375 break; 376 377 case Sema::TDK_Inconsistent: 378 case Sema::TDK_Underqualified: { 379 // FIXME: Should allocate from normal heap so that we can free this later. 380 DFIParamWithArguments *Saved = new (Context) DFIParamWithArguments; 381 Saved->Param = Info.Param; 382 Saved->FirstArg = Info.FirstArg; 383 Saved->SecondArg = Info.SecondArg; 384 Result.Data = Saved; 385 break; 386 } 387 388 case Sema::TDK_SubstitutionFailure: 389 Result.Data = Info.take(); 390 break; 391 392 case Sema::TDK_NonDeducedMismatch: 393 case Sema::TDK_FailedOverloadResolution: 394 break; 395 } 396 397 return Result; 398} 399 400void OverloadCandidate::DeductionFailureInfo::Destroy() { 401 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 402 case Sema::TDK_Success: 403 case Sema::TDK_InstantiationDepth: 404 case Sema::TDK_Incomplete: 405 case Sema::TDK_TooManyArguments: 406 case Sema::TDK_TooFewArguments: 407 case Sema::TDK_InvalidExplicitArguments: 408 break; 409 410 case Sema::TDK_Inconsistent: 411 case Sema::TDK_Underqualified: 412 // FIXME: Destroy the data? 413 Data = 0; 414 break; 415 416 case Sema::TDK_SubstitutionFailure: 417 // FIXME: Destroy the template arugment list? 418 Data = 0; 419 break; 420 421 // Unhandled 422 case Sema::TDK_NonDeducedMismatch: 423 case Sema::TDK_FailedOverloadResolution: 424 break; 425 } 426} 427 428TemplateParameter 429OverloadCandidate::DeductionFailureInfo::getTemplateParameter() { 430 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 431 case Sema::TDK_Success: 432 case Sema::TDK_InstantiationDepth: 433 case Sema::TDK_TooManyArguments: 434 case Sema::TDK_TooFewArguments: 435 case Sema::TDK_SubstitutionFailure: 436 return TemplateParameter(); 437 438 case Sema::TDK_Incomplete: 439 case Sema::TDK_InvalidExplicitArguments: 440 return TemplateParameter::getFromOpaqueValue(Data); 441 442 case Sema::TDK_Inconsistent: 443 case Sema::TDK_Underqualified: 444 return static_cast<DFIParamWithArguments*>(Data)->Param; 445 446 // Unhandled 447 case Sema::TDK_NonDeducedMismatch: 448 case Sema::TDK_FailedOverloadResolution: 449 break; 450 } 451 452 return TemplateParameter(); 453} 454 455TemplateArgumentList * 456OverloadCandidate::DeductionFailureInfo::getTemplateArgumentList() { 457 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 458 case Sema::TDK_Success: 459 case Sema::TDK_InstantiationDepth: 460 case Sema::TDK_TooManyArguments: 461 case Sema::TDK_TooFewArguments: 462 case Sema::TDK_Incomplete: 463 case Sema::TDK_InvalidExplicitArguments: 464 case Sema::TDK_Inconsistent: 465 case Sema::TDK_Underqualified: 466 return 0; 467 468 case Sema::TDK_SubstitutionFailure: 469 return static_cast<TemplateArgumentList*>(Data); 470 471 // Unhandled 472 case Sema::TDK_NonDeducedMismatch: 473 case Sema::TDK_FailedOverloadResolution: 474 break; 475 } 476 477 return 0; 478} 479 480const TemplateArgument *OverloadCandidate::DeductionFailureInfo::getFirstArg() { 481 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 482 case Sema::TDK_Success: 483 case Sema::TDK_InstantiationDepth: 484 case Sema::TDK_Incomplete: 485 case Sema::TDK_TooManyArguments: 486 case Sema::TDK_TooFewArguments: 487 case Sema::TDK_InvalidExplicitArguments: 488 case Sema::TDK_SubstitutionFailure: 489 return 0; 490 491 case Sema::TDK_Inconsistent: 492 case Sema::TDK_Underqualified: 493 return &static_cast<DFIParamWithArguments*>(Data)->FirstArg; 494 495 // Unhandled 496 case Sema::TDK_NonDeducedMismatch: 497 case Sema::TDK_FailedOverloadResolution: 498 break; 499 } 500 501 return 0; 502} 503 504const TemplateArgument * 505OverloadCandidate::DeductionFailureInfo::getSecondArg() { 506 switch (static_cast<Sema::TemplateDeductionResult>(Result)) { 507 case Sema::TDK_Success: 508 case Sema::TDK_InstantiationDepth: 509 case Sema::TDK_Incomplete: 510 case Sema::TDK_TooManyArguments: 511 case Sema::TDK_TooFewArguments: 512 case Sema::TDK_InvalidExplicitArguments: 513 case Sema::TDK_SubstitutionFailure: 514 return 0; 515 516 case Sema::TDK_Inconsistent: 517 case Sema::TDK_Underqualified: 518 return &static_cast<DFIParamWithArguments*>(Data)->SecondArg; 519 520 // Unhandled 521 case Sema::TDK_NonDeducedMismatch: 522 case Sema::TDK_FailedOverloadResolution: 523 break; 524 } 525 526 return 0; 527} 528 529void OverloadCandidateSet::clear() { 530 inherited::clear(); 531 Functions.clear(); 532} 533 534// IsOverload - Determine whether the given New declaration is an 535// overload of the declarations in Old. This routine returns false if 536// New and Old cannot be overloaded, e.g., if New has the same 537// signature as some function in Old (C++ 1.3.10) or if the Old 538// declarations aren't functions (or function templates) at all. When 539// it does return false, MatchedDecl will point to the decl that New 540// cannot be overloaded with. This decl may be a UsingShadowDecl on 541// top of the underlying declaration. 542// 543// Example: Given the following input: 544// 545// void f(int, float); // #1 546// void f(int, int); // #2 547// int f(int, int); // #3 548// 549// When we process #1, there is no previous declaration of "f", 550// so IsOverload will not be used. 551// 552// When we process #2, Old contains only the FunctionDecl for #1. By 553// comparing the parameter types, we see that #1 and #2 are overloaded 554// (since they have different signatures), so this routine returns 555// false; MatchedDecl is unchanged. 556// 557// When we process #3, Old is an overload set containing #1 and #2. We 558// compare the signatures of #3 to #1 (they're overloaded, so we do 559// nothing) and then #3 to #2. Since the signatures of #3 and #2 are 560// identical (return types of functions are not part of the 561// signature), IsOverload returns false and MatchedDecl will be set to 562// point to the FunctionDecl for #2. 563// 564// 'NewIsUsingShadowDecl' indicates that 'New' is being introduced 565// into a class by a using declaration. The rules for whether to hide 566// shadow declarations ignore some properties which otherwise figure 567// into a function template's signature. 568Sema::OverloadKind 569Sema::CheckOverload(Scope *S, FunctionDecl *New, const LookupResult &Old, 570 NamedDecl *&Match, bool NewIsUsingDecl) { 571 for (LookupResult::iterator I = Old.begin(), E = Old.end(); 572 I != E; ++I) { 573 NamedDecl *OldD = *I; 574 575 bool OldIsUsingDecl = false; 576 if (isa<UsingShadowDecl>(OldD)) { 577 OldIsUsingDecl = true; 578 579 // We can always introduce two using declarations into the same 580 // context, even if they have identical signatures. 581 if (NewIsUsingDecl) continue; 582 583 OldD = cast<UsingShadowDecl>(OldD)->getTargetDecl(); 584 } 585 586 // If either declaration was introduced by a using declaration, 587 // we'll need to use slightly different rules for matching. 588 // Essentially, these rules are the normal rules, except that 589 // function templates hide function templates with different 590 // return types or template parameter lists. 591 bool UseMemberUsingDeclRules = 592 (OldIsUsingDecl || NewIsUsingDecl) && CurContext->isRecord(); 593 594 if (FunctionTemplateDecl *OldT = dyn_cast<FunctionTemplateDecl>(OldD)) { 595 if (!IsOverload(New, OldT->getTemplatedDecl(), UseMemberUsingDeclRules)) { 596 if (UseMemberUsingDeclRules && OldIsUsingDecl) { 597 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I)); 598 continue; 599 } 600 601 Match = *I; 602 return Ovl_Match; 603 } 604 } else if (FunctionDecl *OldF = dyn_cast<FunctionDecl>(OldD)) { 605 if (!IsOverload(New, OldF, UseMemberUsingDeclRules)) { 606 if (UseMemberUsingDeclRules && OldIsUsingDecl) { 607 HideUsingShadowDecl(S, cast<UsingShadowDecl>(*I)); 608 continue; 609 } 610 611 Match = *I; 612 return Ovl_Match; 613 } 614 } else if (isa<UsingDecl>(OldD)) { 615 // We can overload with these, which can show up when doing 616 // redeclaration checks for UsingDecls. 617 assert(Old.getLookupKind() == LookupUsingDeclName); 618 } else if (isa<TagDecl>(OldD)) { 619 // We can always overload with tags by hiding them. 620 } else if (isa<UnresolvedUsingValueDecl>(OldD)) { 621 // Optimistically assume that an unresolved using decl will 622 // overload; if it doesn't, we'll have to diagnose during 623 // template instantiation. 624 } else { 625 // (C++ 13p1): 626 // Only function declarations can be overloaded; object and type 627 // declarations cannot be overloaded. 628 Match = *I; 629 return Ovl_NonFunction; 630 } 631 } 632 633 return Ovl_Overload; 634} 635 636bool Sema::IsOverload(FunctionDecl *New, FunctionDecl *Old, 637 bool UseUsingDeclRules) { 638 // If both of the functions are extern "C", then they are not 639 // overloads. 640 if (Old->isExternC() && New->isExternC()) 641 return false; 642 643 FunctionTemplateDecl *OldTemplate = Old->getDescribedFunctionTemplate(); 644 FunctionTemplateDecl *NewTemplate = New->getDescribedFunctionTemplate(); 645 646 // C++ [temp.fct]p2: 647 // A function template can be overloaded with other function templates 648 // and with normal (non-template) functions. 649 if ((OldTemplate == 0) != (NewTemplate == 0)) 650 return true; 651 652 // Is the function New an overload of the function Old? 653 QualType OldQType = Context.getCanonicalType(Old->getType()); 654 QualType NewQType = Context.getCanonicalType(New->getType()); 655 656 // Compare the signatures (C++ 1.3.10) of the two functions to 657 // determine whether they are overloads. If we find any mismatch 658 // in the signature, they are overloads. 659 660 // If either of these functions is a K&R-style function (no 661 // prototype), then we consider them to have matching signatures. 662 if (isa<FunctionNoProtoType>(OldQType.getTypePtr()) || 663 isa<FunctionNoProtoType>(NewQType.getTypePtr())) 664 return false; 665 666 const FunctionProtoType* OldType = cast<FunctionProtoType>(OldQType); 667 const FunctionProtoType* NewType = cast<FunctionProtoType>(NewQType); 668 669 // The signature of a function includes the types of its 670 // parameters (C++ 1.3.10), which includes the presence or absence 671 // of the ellipsis; see C++ DR 357). 672 if (OldQType != NewQType && 673 (OldType->getNumArgs() != NewType->getNumArgs() || 674 OldType->isVariadic() != NewType->isVariadic() || 675 !FunctionArgTypesAreEqual(OldType, NewType))) 676 return true; 677 678 // C++ [temp.over.link]p4: 679 // The signature of a function template consists of its function 680 // signature, its return type and its template parameter list. The names 681 // of the template parameters are significant only for establishing the 682 // relationship between the template parameters and the rest of the 683 // signature. 684 // 685 // We check the return type and template parameter lists for function 686 // templates first; the remaining checks follow. 687 // 688 // However, we don't consider either of these when deciding whether 689 // a member introduced by a shadow declaration is hidden. 690 if (!UseUsingDeclRules && NewTemplate && 691 (!TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(), 692 OldTemplate->getTemplateParameters(), 693 false, TPL_TemplateMatch) || 694 OldType->getResultType() != NewType->getResultType())) 695 return true; 696 697 // If the function is a class member, its signature includes the 698 // cv-qualifiers (if any) and ref-qualifier (if any) on the function itself. 699 // 700 // As part of this, also check whether one of the member functions 701 // is static, in which case they are not overloads (C++ 702 // 13.1p2). While not part of the definition of the signature, 703 // this check is important to determine whether these functions 704 // can be overloaded. 705 CXXMethodDecl* OldMethod = dyn_cast<CXXMethodDecl>(Old); 706 CXXMethodDecl* NewMethod = dyn_cast<CXXMethodDecl>(New); 707 if (OldMethod && NewMethod && 708 !OldMethod->isStatic() && !NewMethod->isStatic() && 709 (OldMethod->getTypeQualifiers() != NewMethod->getTypeQualifiers() || 710 OldMethod->getRefQualifier() != NewMethod->getRefQualifier())) { 711 if (!UseUsingDeclRules && 712 OldMethod->getRefQualifier() != NewMethod->getRefQualifier() && 713 (OldMethod->getRefQualifier() == RQ_None || 714 NewMethod->getRefQualifier() == RQ_None)) { 715 // C++0x [over.load]p2: 716 // - Member function declarations with the same name and the same 717 // parameter-type-list as well as member function template 718 // declarations with the same name, the same parameter-type-list, and 719 // the same template parameter lists cannot be overloaded if any of 720 // them, but not all, have a ref-qualifier (8.3.5). 721 Diag(NewMethod->getLocation(), diag::err_ref_qualifier_overload) 722 << NewMethod->getRefQualifier() << OldMethod->getRefQualifier(); 723 Diag(OldMethod->getLocation(), diag::note_previous_declaration); 724 } 725 726 return true; 727 } 728 729 // The signatures match; this is not an overload. 730 return false; 731} 732 733/// TryImplicitConversion - Attempt to perform an implicit conversion 734/// from the given expression (Expr) to the given type (ToType). This 735/// function returns an implicit conversion sequence that can be used 736/// to perform the initialization. Given 737/// 738/// void f(float f); 739/// void g(int i) { f(i); } 740/// 741/// this routine would produce an implicit conversion sequence to 742/// describe the initialization of f from i, which will be a standard 743/// conversion sequence containing an lvalue-to-rvalue conversion (C++ 744/// 4.1) followed by a floating-integral conversion (C++ 4.9). 745// 746/// Note that this routine only determines how the conversion can be 747/// performed; it does not actually perform the conversion. As such, 748/// it will not produce any diagnostics if no conversion is available, 749/// but will instead return an implicit conversion sequence of kind 750/// "BadConversion". 751/// 752/// If @p SuppressUserConversions, then user-defined conversions are 753/// not permitted. 754/// If @p AllowExplicit, then explicit user-defined conversions are 755/// permitted. 756static ImplicitConversionSequence 757TryImplicitConversion(Sema &S, Expr *From, QualType ToType, 758 bool SuppressUserConversions, 759 bool AllowExplicit, 760 bool InOverloadResolution, 761 bool CStyle) { 762 ImplicitConversionSequence ICS; 763 if (IsStandardConversion(S, From, ToType, InOverloadResolution, 764 ICS.Standard, CStyle)) { 765 ICS.setStandard(); 766 return ICS; 767 } 768 769 if (!S.getLangOptions().CPlusPlus) { 770 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 771 return ICS; 772 } 773 774 // C++ [over.ics.user]p4: 775 // A conversion of an expression of class type to the same class 776 // type is given Exact Match rank, and a conversion of an 777 // expression of class type to a base class of that type is 778 // given Conversion rank, in spite of the fact that a copy/move 779 // constructor (i.e., a user-defined conversion function) is 780 // called for those cases. 781 QualType FromType = From->getType(); 782 if (ToType->getAs<RecordType>() && FromType->getAs<RecordType>() && 783 (S.Context.hasSameUnqualifiedType(FromType, ToType) || 784 S.IsDerivedFrom(FromType, ToType))) { 785 ICS.setStandard(); 786 ICS.Standard.setAsIdentityConversion(); 787 ICS.Standard.setFromType(FromType); 788 ICS.Standard.setAllToTypes(ToType); 789 790 // We don't actually check at this point whether there is a valid 791 // copy/move constructor, since overloading just assumes that it 792 // exists. When we actually perform initialization, we'll find the 793 // appropriate constructor to copy the returned object, if needed. 794 ICS.Standard.CopyConstructor = 0; 795 796 // Determine whether this is considered a derived-to-base conversion. 797 if (!S.Context.hasSameUnqualifiedType(FromType, ToType)) 798 ICS.Standard.Second = ICK_Derived_To_Base; 799 800 return ICS; 801 } 802 803 if (SuppressUserConversions) { 804 // We're not in the case above, so there is no conversion that 805 // we can perform. 806 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 807 return ICS; 808 } 809 810 // Attempt user-defined conversion. 811 OverloadCandidateSet Conversions(From->getExprLoc()); 812 OverloadingResult UserDefResult 813 = IsUserDefinedConversion(S, From, ToType, ICS.UserDefined, Conversions, 814 AllowExplicit); 815 816 if (UserDefResult == OR_Success) { 817 ICS.setUserDefined(); 818 // C++ [over.ics.user]p4: 819 // A conversion of an expression of class type to the same class 820 // type is given Exact Match rank, and a conversion of an 821 // expression of class type to a base class of that type is 822 // given Conversion rank, in spite of the fact that a copy 823 // constructor (i.e., a user-defined conversion function) is 824 // called for those cases. 825 if (CXXConstructorDecl *Constructor 826 = dyn_cast<CXXConstructorDecl>(ICS.UserDefined.ConversionFunction)) { 827 QualType FromCanon 828 = S.Context.getCanonicalType(From->getType().getUnqualifiedType()); 829 QualType ToCanon 830 = S.Context.getCanonicalType(ToType).getUnqualifiedType(); 831 if (Constructor->isCopyConstructor() && 832 (FromCanon == ToCanon || S.IsDerivedFrom(FromCanon, ToCanon))) { 833 // Turn this into a "standard" conversion sequence, so that it 834 // gets ranked with standard conversion sequences. 835 ICS.setStandard(); 836 ICS.Standard.setAsIdentityConversion(); 837 ICS.Standard.setFromType(From->getType()); 838 ICS.Standard.setAllToTypes(ToType); 839 ICS.Standard.CopyConstructor = Constructor; 840 if (ToCanon != FromCanon) 841 ICS.Standard.Second = ICK_Derived_To_Base; 842 } 843 } 844 845 // C++ [over.best.ics]p4: 846 // However, when considering the argument of a user-defined 847 // conversion function that is a candidate by 13.3.1.3 when 848 // invoked for the copying of the temporary in the second step 849 // of a class copy-initialization, or by 13.3.1.4, 13.3.1.5, or 850 // 13.3.1.6 in all cases, only standard conversion sequences and 851 // ellipsis conversion sequences are allowed. 852 if (SuppressUserConversions && ICS.isUserDefined()) { 853 ICS.setBad(BadConversionSequence::suppressed_user, From, ToType); 854 } 855 } else if (UserDefResult == OR_Ambiguous && !SuppressUserConversions) { 856 ICS.setAmbiguous(); 857 ICS.Ambiguous.setFromType(From->getType()); 858 ICS.Ambiguous.setToType(ToType); 859 for (OverloadCandidateSet::iterator Cand = Conversions.begin(); 860 Cand != Conversions.end(); ++Cand) 861 if (Cand->Viable) 862 ICS.Ambiguous.addConversion(Cand->Function); 863 } else { 864 ICS.setBad(BadConversionSequence::no_conversion, From, ToType); 865 } 866 867 return ICS; 868} 869 870bool Sema::TryImplicitConversion(InitializationSequence &Sequence, 871 const InitializedEntity &Entity, 872 Expr *Initializer, 873 bool SuppressUserConversions, 874 bool AllowExplicitConversions, 875 bool InOverloadResolution, 876 bool CStyle) { 877 ImplicitConversionSequence ICS 878 = clang::TryImplicitConversion(*this, Initializer, Entity.getType(), 879 SuppressUserConversions, 880 AllowExplicitConversions, 881 InOverloadResolution, 882 CStyle); 883 if (ICS.isBad()) return true; 884 885 // Perform the actual conversion. 886 Sequence.AddConversionSequenceStep(ICS, Entity.getType()); 887 return false; 888} 889 890/// PerformImplicitConversion - Perform an implicit conversion of the 891/// expression From to the type ToType. Returns the 892/// converted expression. Flavor is the kind of conversion we're 893/// performing, used in the error message. If @p AllowExplicit, 894/// explicit user-defined conversions are permitted. 895ExprResult 896Sema::PerformImplicitConversion(Expr *From, QualType ToType, 897 AssignmentAction Action, bool AllowExplicit) { 898 ImplicitConversionSequence ICS; 899 return PerformImplicitConversion(From, ToType, Action, AllowExplicit, ICS); 900} 901 902ExprResult 903Sema::PerformImplicitConversion(Expr *From, QualType ToType, 904 AssignmentAction Action, bool AllowExplicit, 905 ImplicitConversionSequence& ICS) { 906 ICS = clang::TryImplicitConversion(*this, From, ToType, 907 /*SuppressUserConversions=*/false, 908 AllowExplicit, 909 /*InOverloadResolution=*/false, 910 /*CStyle=*/false); 911 return PerformImplicitConversion(From, ToType, ICS, Action); 912} 913 914/// \brief Determine whether the conversion from FromType to ToType is a valid 915/// conversion that strips "noreturn" off the nested function type. 916static bool IsNoReturnConversion(ASTContext &Context, QualType FromType, 917 QualType ToType, QualType &ResultTy) { 918 if (Context.hasSameUnqualifiedType(FromType, ToType)) 919 return false; 920 921 // Permit the conversion F(t __attribute__((noreturn))) -> F(t) 922 // where F adds one of the following at most once: 923 // - a pointer 924 // - a member pointer 925 // - a block pointer 926 CanQualType CanTo = Context.getCanonicalType(ToType); 927 CanQualType CanFrom = Context.getCanonicalType(FromType); 928 Type::TypeClass TyClass = CanTo->getTypeClass(); 929 if (TyClass != CanFrom->getTypeClass()) return false; 930 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) { 931 if (TyClass == Type::Pointer) { 932 CanTo = CanTo.getAs<PointerType>()->getPointeeType(); 933 CanFrom = CanFrom.getAs<PointerType>()->getPointeeType(); 934 } else if (TyClass == Type::BlockPointer) { 935 CanTo = CanTo.getAs<BlockPointerType>()->getPointeeType(); 936 CanFrom = CanFrom.getAs<BlockPointerType>()->getPointeeType(); 937 } else if (TyClass == Type::MemberPointer) { 938 CanTo = CanTo.getAs<MemberPointerType>()->getPointeeType(); 939 CanFrom = CanFrom.getAs<MemberPointerType>()->getPointeeType(); 940 } else { 941 return false; 942 } 943 944 TyClass = CanTo->getTypeClass(); 945 if (TyClass != CanFrom->getTypeClass()) return false; 946 if (TyClass != Type::FunctionProto && TyClass != Type::FunctionNoProto) 947 return false; 948 } 949 950 const FunctionType *FromFn = cast<FunctionType>(CanFrom); 951 FunctionType::ExtInfo EInfo = FromFn->getExtInfo(); 952 if (!EInfo.getNoReturn()) return false; 953 954 FromFn = Context.adjustFunctionType(FromFn, EInfo.withNoReturn(false)); 955 assert(QualType(FromFn, 0).isCanonical()); 956 if (QualType(FromFn, 0) != CanTo) return false; 957 958 ResultTy = ToType; 959 return true; 960} 961 962/// \brief Determine whether the conversion from FromType to ToType is a valid 963/// vector conversion. 964/// 965/// \param ICK Will be set to the vector conversion kind, if this is a vector 966/// conversion. 967static bool IsVectorConversion(ASTContext &Context, QualType FromType, 968 QualType ToType, ImplicitConversionKind &ICK) { 969 // We need at least one of these types to be a vector type to have a vector 970 // conversion. 971 if (!ToType->isVectorType() && !FromType->isVectorType()) 972 return false; 973 974 // Identical types require no conversions. 975 if (Context.hasSameUnqualifiedType(FromType, ToType)) 976 return false; 977 978 // There are no conversions between extended vector types, only identity. 979 if (ToType->isExtVectorType()) { 980 // There are no conversions between extended vector types other than the 981 // identity conversion. 982 if (FromType->isExtVectorType()) 983 return false; 984 985 // Vector splat from any arithmetic type to a vector. 986 if (FromType->isArithmeticType()) { 987 ICK = ICK_Vector_Splat; 988 return true; 989 } 990 } 991 992 // We can perform the conversion between vector types in the following cases: 993 // 1)vector types are equivalent AltiVec and GCC vector types 994 // 2)lax vector conversions are permitted and the vector types are of the 995 // same size 996 if (ToType->isVectorType() && FromType->isVectorType()) { 997 if (Context.areCompatibleVectorTypes(FromType, ToType) || 998 (Context.getLangOptions().LaxVectorConversions && 999 (Context.getTypeSize(FromType) == Context.getTypeSize(ToType)))) { 1000 ICK = ICK_Vector_Conversion; 1001 return true; 1002 } 1003 } 1004 1005 return false; 1006} 1007 1008/// IsStandardConversion - Determines whether there is a standard 1009/// conversion sequence (C++ [conv], C++ [over.ics.scs]) from the 1010/// expression From to the type ToType. Standard conversion sequences 1011/// only consider non-class types; for conversions that involve class 1012/// types, use TryImplicitConversion. If a conversion exists, SCS will 1013/// contain the standard conversion sequence required to perform this 1014/// conversion and this routine will return true. Otherwise, this 1015/// routine will return false and the value of SCS is unspecified. 1016static bool IsStandardConversion(Sema &S, Expr* From, QualType ToType, 1017 bool InOverloadResolution, 1018 StandardConversionSequence &SCS, 1019 bool CStyle) { 1020 QualType FromType = From->getType(); 1021 1022 // Standard conversions (C++ [conv]) 1023 SCS.setAsIdentityConversion(); 1024 SCS.DeprecatedStringLiteralToCharPtr = false; 1025 SCS.IncompatibleObjC = false; 1026 SCS.setFromType(FromType); 1027 SCS.CopyConstructor = 0; 1028 1029 // There are no standard conversions for class types in C++, so 1030 // abort early. When overloading in C, however, we do permit 1031 if (FromType->isRecordType() || ToType->isRecordType()) { 1032 if (S.getLangOptions().CPlusPlus) 1033 return false; 1034 1035 // When we're overloading in C, we allow, as standard conversions, 1036 } 1037 1038 // The first conversion can be an lvalue-to-rvalue conversion, 1039 // array-to-pointer conversion, or function-to-pointer conversion 1040 // (C++ 4p1). 1041 1042 if (FromType == S.Context.OverloadTy) { 1043 DeclAccessPair AccessPair; 1044 if (FunctionDecl *Fn 1045 = S.ResolveAddressOfOverloadedFunction(From, ToType, false, 1046 AccessPair)) { 1047 // We were able to resolve the address of the overloaded function, 1048 // so we can convert to the type of that function. 1049 FromType = Fn->getType(); 1050 1051 // we can sometimes resolve &foo<int> regardless of ToType, so check 1052 // if the type matches (identity) or we are converting to bool 1053 if (!S.Context.hasSameUnqualifiedType( 1054 S.ExtractUnqualifiedFunctionType(ToType), FromType)) { 1055 QualType resultTy; 1056 // if the function type matches except for [[noreturn]], it's ok 1057 if (!IsNoReturnConversion(S.Context, FromType, 1058 S.ExtractUnqualifiedFunctionType(ToType), resultTy)) 1059 // otherwise, only a boolean conversion is standard 1060 if (!ToType->isBooleanType()) 1061 return false; 1062 } 1063 1064 // Check if the "from" expression is taking the address of an overloaded 1065 // function and recompute the FromType accordingly. Take advantage of the 1066 // fact that non-static member functions *must* have such an address-of 1067 // expression. 1068 CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn); 1069 if (Method && !Method->isStatic()) { 1070 assert(isa<UnaryOperator>(From->IgnoreParens()) && 1071 "Non-unary operator on non-static member address"); 1072 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() 1073 == UO_AddrOf && 1074 "Non-address-of operator on non-static member address"); 1075 const Type *ClassType 1076 = S.Context.getTypeDeclType(Method->getParent()).getTypePtr(); 1077 FromType = S.Context.getMemberPointerType(FromType, ClassType); 1078 } else if (isa<UnaryOperator>(From->IgnoreParens())) { 1079 assert(cast<UnaryOperator>(From->IgnoreParens())->getOpcode() == 1080 UO_AddrOf && 1081 "Non-address-of operator for overloaded function expression"); 1082 FromType = S.Context.getPointerType(FromType); 1083 } 1084 1085 // Check that we've computed the proper type after overload resolution. 1086 assert(S.Context.hasSameType( 1087 FromType, 1088 S.FixOverloadedFunctionReference(From, AccessPair, Fn)->getType())); 1089 } else { 1090 return false; 1091 } 1092 } 1093 // Lvalue-to-rvalue conversion (C++ 4.1): 1094 // An lvalue (3.10) of a non-function, non-array type T can be 1095 // converted to an rvalue. 1096 bool argIsLValue = From->isLValue(); 1097 if (argIsLValue && 1098 !FromType->isFunctionType() && !FromType->isArrayType() && 1099 S.Context.getCanonicalType(FromType) != S.Context.OverloadTy) { 1100 SCS.First = ICK_Lvalue_To_Rvalue; 1101 1102 // If T is a non-class type, the type of the rvalue is the 1103 // cv-unqualified version of T. Otherwise, the type of the rvalue 1104 // is T (C++ 4.1p1). C++ can't get here with class types; in C, we 1105 // just strip the qualifiers because they don't matter. 1106 FromType = FromType.getUnqualifiedType(); 1107 } else if (FromType->isArrayType()) { 1108 // Array-to-pointer conversion (C++ 4.2) 1109 SCS.First = ICK_Array_To_Pointer; 1110 1111 // An lvalue or rvalue of type "array of N T" or "array of unknown 1112 // bound of T" can be converted to an rvalue of type "pointer to 1113 // T" (C++ 4.2p1). 1114 FromType = S.Context.getArrayDecayedType(FromType); 1115 1116 if (S.IsStringLiteralToNonConstPointerConversion(From, ToType)) { 1117 // This conversion is deprecated. (C++ D.4). 1118 SCS.DeprecatedStringLiteralToCharPtr = true; 1119 1120 // For the purpose of ranking in overload resolution 1121 // (13.3.3.1.1), this conversion is considered an 1122 // array-to-pointer conversion followed by a qualification 1123 // conversion (4.4). (C++ 4.2p2) 1124 SCS.Second = ICK_Identity; 1125 SCS.Third = ICK_Qualification; 1126 SCS.setAllToTypes(FromType); 1127 return true; 1128 } 1129 } else if (FromType->isFunctionType() && argIsLValue) { 1130 // Function-to-pointer conversion (C++ 4.3). 1131 SCS.First = ICK_Function_To_Pointer; 1132 1133 // An lvalue of function type T can be converted to an rvalue of 1134 // type "pointer to T." The result is a pointer to the 1135 // function. (C++ 4.3p1). 1136 FromType = S.Context.getPointerType(FromType); 1137 } else { 1138 // We don't require any conversions for the first step. 1139 SCS.First = ICK_Identity; 1140 } 1141 SCS.setToType(0, FromType); 1142 1143 // The second conversion can be an integral promotion, floating 1144 // point promotion, integral conversion, floating point conversion, 1145 // floating-integral conversion, pointer conversion, 1146 // pointer-to-member conversion, or boolean conversion (C++ 4p1). 1147 // For overloading in C, this can also be a "compatible-type" 1148 // conversion. 1149 bool IncompatibleObjC = false; 1150 ImplicitConversionKind SecondICK = ICK_Identity; 1151 if (S.Context.hasSameUnqualifiedType(FromType, ToType)) { 1152 // The unqualified versions of the types are the same: there's no 1153 // conversion to do. 1154 SCS.Second = ICK_Identity; 1155 } else if (S.IsIntegralPromotion(From, FromType, ToType)) { 1156 // Integral promotion (C++ 4.5). 1157 SCS.Second = ICK_Integral_Promotion; 1158 FromType = ToType.getUnqualifiedType(); 1159 } else if (S.IsFloatingPointPromotion(FromType, ToType)) { 1160 // Floating point promotion (C++ 4.6). 1161 SCS.Second = ICK_Floating_Promotion; 1162 FromType = ToType.getUnqualifiedType(); 1163 } else if (S.IsComplexPromotion(FromType, ToType)) { 1164 // Complex promotion (Clang extension) 1165 SCS.Second = ICK_Complex_Promotion; 1166 FromType = ToType.getUnqualifiedType(); 1167 } else if (ToType->isBooleanType() && 1168 (FromType->isArithmeticType() || 1169 FromType->isAnyPointerType() || 1170 FromType->isBlockPointerType() || 1171 FromType->isMemberPointerType() || 1172 FromType->isNullPtrType())) { 1173 // Boolean conversions (C++ 4.12). 1174 SCS.Second = ICK_Boolean_Conversion; 1175 FromType = S.Context.BoolTy; 1176 } else if (FromType->isIntegralOrUnscopedEnumerationType() && 1177 ToType->isIntegralType(S.Context)) { 1178 // Integral conversions (C++ 4.7). 1179 SCS.Second = ICK_Integral_Conversion; 1180 FromType = ToType.getUnqualifiedType(); 1181 } else if (FromType->isAnyComplexType() && ToType->isComplexType()) { 1182 // Complex conversions (C99 6.3.1.6) 1183 SCS.Second = ICK_Complex_Conversion; 1184 FromType = ToType.getUnqualifiedType(); 1185 } else if ((FromType->isAnyComplexType() && ToType->isArithmeticType()) || 1186 (ToType->isAnyComplexType() && FromType->isArithmeticType())) { 1187 // Complex-real conversions (C99 6.3.1.7) 1188 SCS.Second = ICK_Complex_Real; 1189 FromType = ToType.getUnqualifiedType(); 1190 } else if (FromType->isRealFloatingType() && ToType->isRealFloatingType()) { 1191 // Floating point conversions (C++ 4.8). 1192 SCS.Second = ICK_Floating_Conversion; 1193 FromType = ToType.getUnqualifiedType(); 1194 } else if ((FromType->isRealFloatingType() && 1195 ToType->isIntegralType(S.Context)) || 1196 (FromType->isIntegralOrUnscopedEnumerationType() && 1197 ToType->isRealFloatingType())) { 1198 // Floating-integral conversions (C++ 4.9). 1199 SCS.Second = ICK_Floating_Integral; 1200 FromType = ToType.getUnqualifiedType(); 1201 } else if (S.IsBlockPointerConversion(FromType, ToType, FromType)) { 1202 SCS.Second = ICK_Block_Pointer_Conversion; 1203 } else if (S.IsPointerConversion(From, FromType, ToType, InOverloadResolution, 1204 FromType, IncompatibleObjC)) { 1205 // Pointer conversions (C++ 4.10). 1206 SCS.Second = ICK_Pointer_Conversion; 1207 SCS.IncompatibleObjC = IncompatibleObjC; 1208 FromType = FromType.getUnqualifiedType(); 1209 } else if (S.IsMemberPointerConversion(From, FromType, ToType, 1210 InOverloadResolution, FromType)) { 1211 // Pointer to member conversions (4.11). 1212 SCS.Second = ICK_Pointer_Member; 1213 } else if (IsVectorConversion(S.Context, FromType, ToType, SecondICK)) { 1214 SCS.Second = SecondICK; 1215 FromType = ToType.getUnqualifiedType(); 1216 } else if (!S.getLangOptions().CPlusPlus && 1217 S.Context.typesAreCompatible(ToType, FromType)) { 1218 // Compatible conversions (Clang extension for C function overloading) 1219 SCS.Second = ICK_Compatible_Conversion; 1220 FromType = ToType.getUnqualifiedType(); 1221 } else if (IsNoReturnConversion(S.Context, FromType, ToType, FromType)) { 1222 // Treat a conversion that strips "noreturn" as an identity conversion. 1223 SCS.Second = ICK_NoReturn_Adjustment; 1224 } else if (IsTransparentUnionStandardConversion(S, From, ToType, 1225 InOverloadResolution, 1226 SCS, CStyle)) { 1227 SCS.Second = ICK_TransparentUnionConversion; 1228 FromType = ToType; 1229 } else { 1230 // No second conversion required. 1231 SCS.Second = ICK_Identity; 1232 } 1233 SCS.setToType(1, FromType); 1234 1235 QualType CanonFrom; 1236 QualType CanonTo; 1237 // The third conversion can be a qualification conversion (C++ 4p1). 1238 if (S.IsQualificationConversion(FromType, ToType, CStyle)) { 1239 SCS.Third = ICK_Qualification; 1240 FromType = ToType; 1241 CanonFrom = S.Context.getCanonicalType(FromType); 1242 CanonTo = S.Context.getCanonicalType(ToType); 1243 } else { 1244 // No conversion required 1245 SCS.Third = ICK_Identity; 1246 1247 // C++ [over.best.ics]p6: 1248 // [...] Any difference in top-level cv-qualification is 1249 // subsumed by the initialization itself and does not constitute 1250 // a conversion. [...] 1251 CanonFrom = S.Context.getCanonicalType(FromType); 1252 CanonTo = S.Context.getCanonicalType(ToType); 1253 if (CanonFrom.getLocalUnqualifiedType() 1254 == CanonTo.getLocalUnqualifiedType() && 1255 (CanonFrom.getLocalCVRQualifiers() != CanonTo.getLocalCVRQualifiers() 1256 || CanonFrom.getObjCGCAttr() != CanonTo.getObjCGCAttr())) { 1257 FromType = ToType; 1258 CanonFrom = CanonTo; 1259 } 1260 } 1261 SCS.setToType(2, FromType); 1262 1263 // If we have not converted the argument type to the parameter type, 1264 // this is a bad conversion sequence. 1265 if (CanonFrom != CanonTo) 1266 return false; 1267 1268 return true; 1269} 1270 1271static bool 1272IsTransparentUnionStandardConversion(Sema &S, Expr* From, 1273 QualType &ToType, 1274 bool InOverloadResolution, 1275 StandardConversionSequence &SCS, 1276 bool CStyle) { 1277 1278 const RecordType *UT = ToType->getAsUnionType(); 1279 if (!UT || !UT->getDecl()->hasAttr<TransparentUnionAttr>()) 1280 return false; 1281 // The field to initialize within the transparent union. 1282 RecordDecl *UD = UT->getDecl(); 1283 // It's compatible if the expression matches any of the fields. 1284 for (RecordDecl::field_iterator it = UD->field_begin(), 1285 itend = UD->field_end(); 1286 it != itend; ++it) { 1287 if (IsStandardConversion(S, From, it->getType(), InOverloadResolution, SCS, CStyle)) { 1288 ToType = it->getType(); 1289 return true; 1290 } 1291 } 1292 return false; 1293} 1294 1295/// IsIntegralPromotion - Determines whether the conversion from the 1296/// expression From (whose potentially-adjusted type is FromType) to 1297/// ToType is an integral promotion (C++ 4.5). If so, returns true and 1298/// sets PromotedType to the promoted type. 1299bool Sema::IsIntegralPromotion(Expr *From, QualType FromType, QualType ToType) { 1300 const BuiltinType *To = ToType->getAs<BuiltinType>(); 1301 // All integers are built-in. 1302 if (!To) { 1303 return false; 1304 } 1305 1306 // An rvalue of type char, signed char, unsigned char, short int, or 1307 // unsigned short int can be converted to an rvalue of type int if 1308 // int can represent all the values of the source type; otherwise, 1309 // the source rvalue can be converted to an rvalue of type unsigned 1310 // int (C++ 4.5p1). 1311 if (FromType->isPromotableIntegerType() && !FromType->isBooleanType() && 1312 !FromType->isEnumeralType()) { 1313 if (// We can promote any signed, promotable integer type to an int 1314 (FromType->isSignedIntegerType() || 1315 // We can promote any unsigned integer type whose size is 1316 // less than int to an int. 1317 (!FromType->isSignedIntegerType() && 1318 Context.getTypeSize(FromType) < Context.getTypeSize(ToType)))) { 1319 return To->getKind() == BuiltinType::Int; 1320 } 1321 1322 return To->getKind() == BuiltinType::UInt; 1323 } 1324 1325 // C++0x [conv.prom]p3: 1326 // A prvalue of an unscoped enumeration type whose underlying type is not 1327 // fixed (7.2) can be converted to an rvalue a prvalue of the first of the 1328 // following types that can represent all the values of the enumeration 1329 // (i.e., the values in the range bmin to bmax as described in 7.2): int, 1330 // unsigned int, long int, unsigned long int, long long int, or unsigned 1331 // long long int. If none of the types in that list can represent all the 1332 // values of the enumeration, an rvalue a prvalue of an unscoped enumeration 1333 // type can be converted to an rvalue a prvalue of the extended integer type 1334 // with lowest integer conversion rank (4.13) greater than the rank of long 1335 // long in which all the values of the enumeration can be represented. If 1336 // there are two such extended types, the signed one is chosen. 1337 if (const EnumType *FromEnumType = FromType->getAs<EnumType>()) { 1338 // C++0x 7.2p9: Note that this implicit enum to int conversion is not 1339 // provided for a scoped enumeration. 1340 if (FromEnumType->getDecl()->isScoped()) 1341 return false; 1342 1343 // We have already pre-calculated the promotion type, so this is trivial. 1344 if (ToType->isIntegerType() && 1345 !RequireCompleteType(From->getLocStart(), FromType, PDiag())) 1346 return Context.hasSameUnqualifiedType(ToType, 1347 FromEnumType->getDecl()->getPromotionType()); 1348 } 1349 1350 // C++0x [conv.prom]p2: 1351 // A prvalue of type char16_t, char32_t, or wchar_t (3.9.1) can be converted 1352 // to an rvalue a prvalue of the first of the following types that can 1353 // represent all the values of its underlying type: int, unsigned int, 1354 // long int, unsigned long int, long long int, or unsigned long long int. 1355 // If none of the types in that list can represent all the values of its 1356 // underlying type, an rvalue a prvalue of type char16_t, char32_t, 1357 // or wchar_t can be converted to an rvalue a prvalue of its underlying 1358 // type. 1359 if (FromType->isAnyCharacterType() && !FromType->isCharType() && 1360 ToType->isIntegerType()) { 1361 // Determine whether the type we're converting from is signed or 1362 // unsigned. 1363 bool FromIsSigned; 1364 uint64_t FromSize = Context.getTypeSize(FromType); 1365 1366 // FIXME: Is wchar_t signed or unsigned? We assume it's signed for now. 1367 FromIsSigned = true; 1368 1369 // The types we'll try to promote to, in the appropriate 1370 // order. Try each of these types. 1371 QualType PromoteTypes[6] = { 1372 Context.IntTy, Context.UnsignedIntTy, 1373 Context.LongTy, Context.UnsignedLongTy , 1374 Context.LongLongTy, Context.UnsignedLongLongTy 1375 }; 1376 for (int Idx = 0; Idx < 6; ++Idx) { 1377 uint64_t ToSize = Context.getTypeSize(PromoteTypes[Idx]); 1378 if (FromSize < ToSize || 1379 (FromSize == ToSize && 1380 FromIsSigned == PromoteTypes[Idx]->isSignedIntegerType())) { 1381 // We found the type that we can promote to. If this is the 1382 // type we wanted, we have a promotion. Otherwise, no 1383 // promotion. 1384 return Context.hasSameUnqualifiedType(ToType, PromoteTypes[Idx]); 1385 } 1386 } 1387 } 1388 1389 // An rvalue for an integral bit-field (9.6) can be converted to an 1390 // rvalue of type int if int can represent all the values of the 1391 // bit-field; otherwise, it can be converted to unsigned int if 1392 // unsigned int can represent all the values of the bit-field. If 1393 // the bit-field is larger yet, no integral promotion applies to 1394 // it. If the bit-field has an enumerated type, it is treated as any 1395 // other value of that type for promotion purposes (C++ 4.5p3). 1396 // FIXME: We should delay checking of bit-fields until we actually perform the 1397 // conversion. 1398 using llvm::APSInt; 1399 if (From) 1400 if (FieldDecl *MemberDecl = From->getBitField()) { 1401 APSInt BitWidth; 1402 if (FromType->isIntegralType(Context) && 1403 MemberDecl->getBitWidth()->isIntegerConstantExpr(BitWidth, Context)) { 1404 APSInt ToSize(BitWidth.getBitWidth(), BitWidth.isUnsigned()); 1405 ToSize = Context.getTypeSize(ToType); 1406 1407 // Are we promoting to an int from a bitfield that fits in an int? 1408 if (BitWidth < ToSize || 1409 (FromType->isSignedIntegerType() && BitWidth <= ToSize)) { 1410 return To->getKind() == BuiltinType::Int; 1411 } 1412 1413 // Are we promoting to an unsigned int from an unsigned bitfield 1414 // that fits into an unsigned int? 1415 if (FromType->isUnsignedIntegerType() && BitWidth <= ToSize) { 1416 return To->getKind() == BuiltinType::UInt; 1417 } 1418 1419 return false; 1420 } 1421 } 1422 1423 // An rvalue of type bool can be converted to an rvalue of type int, 1424 // with false becoming zero and true becoming one (C++ 4.5p4). 1425 if (FromType->isBooleanType() && To->getKind() == BuiltinType::Int) { 1426 return true; 1427 } 1428 1429 return false; 1430} 1431 1432/// IsFloatingPointPromotion - Determines whether the conversion from 1433/// FromType to ToType is a floating point promotion (C++ 4.6). If so, 1434/// returns true and sets PromotedType to the promoted type. 1435bool Sema::IsFloatingPointPromotion(QualType FromType, QualType ToType) { 1436 /// An rvalue of type float can be converted to an rvalue of type 1437 /// double. (C++ 4.6p1). 1438 if (const BuiltinType *FromBuiltin = FromType->getAs<BuiltinType>()) 1439 if (const BuiltinType *ToBuiltin = ToType->getAs<BuiltinType>()) { 1440 if (FromBuiltin->getKind() == BuiltinType::Float && 1441 ToBuiltin->getKind() == BuiltinType::Double) 1442 return true; 1443 1444 // C99 6.3.1.5p1: 1445 // When a float is promoted to double or long double, or a 1446 // double is promoted to long double [...]. 1447 if (!getLangOptions().CPlusPlus && 1448 (FromBuiltin->getKind() == BuiltinType::Float || 1449 FromBuiltin->getKind() == BuiltinType::Double) && 1450 (ToBuiltin->getKind() == BuiltinType::LongDouble)) 1451 return true; 1452 } 1453 1454 return false; 1455} 1456 1457/// \brief Determine if a conversion is a complex promotion. 1458/// 1459/// A complex promotion is defined as a complex -> complex conversion 1460/// where the conversion between the underlying real types is a 1461/// floating-point or integral promotion. 1462bool Sema::IsComplexPromotion(QualType FromType, QualType ToType) { 1463 const ComplexType *FromComplex = FromType->getAs<ComplexType>(); 1464 if (!FromComplex) 1465 return false; 1466 1467 const ComplexType *ToComplex = ToType->getAs<ComplexType>(); 1468 if (!ToComplex) 1469 return false; 1470 1471 return IsFloatingPointPromotion(FromComplex->getElementType(), 1472 ToComplex->getElementType()) || 1473 IsIntegralPromotion(0, FromComplex->getElementType(), 1474 ToComplex->getElementType()); 1475} 1476 1477/// BuildSimilarlyQualifiedPointerType - In a pointer conversion from 1478/// the pointer type FromPtr to a pointer to type ToPointee, with the 1479/// same type qualifiers as FromPtr has on its pointee type. ToType, 1480/// if non-empty, will be a pointer to ToType that may or may not have 1481/// the right set of qualifiers on its pointee. 1482static QualType 1483BuildSimilarlyQualifiedPointerType(const Type *FromPtr, 1484 QualType ToPointee, QualType ToType, 1485 ASTContext &Context) { 1486 assert((FromPtr->getTypeClass() == Type::Pointer || 1487 FromPtr->getTypeClass() == Type::ObjCObjectPointer) && 1488 "Invalid similarly-qualified pointer type"); 1489 1490 /// \brief Conversions to 'id' subsume cv-qualifier conversions. 1491 if (ToType->isObjCIdType() || ToType->isObjCQualifiedIdType()) 1492 return ToType.getUnqualifiedType(); 1493 1494 QualType CanonFromPointee 1495 = Context.getCanonicalType(FromPtr->getPointeeType()); 1496 QualType CanonToPointee = Context.getCanonicalType(ToPointee); 1497 Qualifiers Quals = CanonFromPointee.getQualifiers(); 1498 1499 // Exact qualifier match -> return the pointer type we're converting to. 1500 if (CanonToPointee.getLocalQualifiers() == Quals) { 1501 // ToType is exactly what we need. Return it. 1502 if (!ToType.isNull()) 1503 return ToType.getUnqualifiedType(); 1504 1505 // Build a pointer to ToPointee. It has the right qualifiers 1506 // already. 1507 if (isa<ObjCObjectPointerType>(ToType)) 1508 return Context.getObjCObjectPointerType(ToPointee); 1509 return Context.getPointerType(ToPointee); 1510 } 1511 1512 // Just build a canonical type that has the right qualifiers. 1513 QualType QualifiedCanonToPointee 1514 = Context.getQualifiedType(CanonToPointee.getLocalUnqualifiedType(), Quals); 1515 1516 if (isa<ObjCObjectPointerType>(ToType)) 1517 return Context.getObjCObjectPointerType(QualifiedCanonToPointee); 1518 return Context.getPointerType(QualifiedCanonToPointee); 1519} 1520 1521static bool isNullPointerConstantForConversion(Expr *Expr, 1522 bool InOverloadResolution, 1523 ASTContext &Context) { 1524 // Handle value-dependent integral null pointer constants correctly. 1525 // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#903 1526 if (Expr->isValueDependent() && !Expr->isTypeDependent() && 1527 Expr->getType()->isIntegerType() && !Expr->getType()->isEnumeralType()) 1528 return !InOverloadResolution; 1529 1530 return Expr->isNullPointerConstant(Context, 1531 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 1532 : Expr::NPC_ValueDependentIsNull); 1533} 1534 1535/// IsPointerConversion - Determines whether the conversion of the 1536/// expression From, which has the (possibly adjusted) type FromType, 1537/// can be converted to the type ToType via a pointer conversion (C++ 1538/// 4.10). If so, returns true and places the converted type (that 1539/// might differ from ToType in its cv-qualifiers at some level) into 1540/// ConvertedType. 1541/// 1542/// This routine also supports conversions to and from block pointers 1543/// and conversions with Objective-C's 'id', 'id<protocols...>', and 1544/// pointers to interfaces. FIXME: Once we've determined the 1545/// appropriate overloading rules for Objective-C, we may want to 1546/// split the Objective-C checks into a different routine; however, 1547/// GCC seems to consider all of these conversions to be pointer 1548/// conversions, so for now they live here. IncompatibleObjC will be 1549/// set if the conversion is an allowed Objective-C conversion that 1550/// should result in a warning. 1551bool Sema::IsPointerConversion(Expr *From, QualType FromType, QualType ToType, 1552 bool InOverloadResolution, 1553 QualType& ConvertedType, 1554 bool &IncompatibleObjC) { 1555 IncompatibleObjC = false; 1556 if (isObjCPointerConversion(FromType, ToType, ConvertedType, 1557 IncompatibleObjC)) 1558 return true; 1559 1560 // Conversion from a null pointer constant to any Objective-C pointer type. 1561 if (ToType->isObjCObjectPointerType() && 1562 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1563 ConvertedType = ToType; 1564 return true; 1565 } 1566 1567 // Blocks: Block pointers can be converted to void*. 1568 if (FromType->isBlockPointerType() && ToType->isPointerType() && 1569 ToType->getAs<PointerType>()->getPointeeType()->isVoidType()) { 1570 ConvertedType = ToType; 1571 return true; 1572 } 1573 // Blocks: A null pointer constant can be converted to a block 1574 // pointer type. 1575 if (ToType->isBlockPointerType() && 1576 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1577 ConvertedType = ToType; 1578 return true; 1579 } 1580 1581 // If the left-hand-side is nullptr_t, the right side can be a null 1582 // pointer constant. 1583 if (ToType->isNullPtrType() && 1584 isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1585 ConvertedType = ToType; 1586 return true; 1587 } 1588 1589 const PointerType* ToTypePtr = ToType->getAs<PointerType>(); 1590 if (!ToTypePtr) 1591 return false; 1592 1593 // A null pointer constant can be converted to a pointer type (C++ 4.10p1). 1594 if (isNullPointerConstantForConversion(From, InOverloadResolution, Context)) { 1595 ConvertedType = ToType; 1596 return true; 1597 } 1598 1599 // Beyond this point, both types need to be pointers 1600 // , including objective-c pointers. 1601 QualType ToPointeeType = ToTypePtr->getPointeeType(); 1602 if (FromType->isObjCObjectPointerType() && ToPointeeType->isVoidType()) { 1603 ConvertedType = BuildSimilarlyQualifiedPointerType( 1604 FromType->getAs<ObjCObjectPointerType>(), 1605 ToPointeeType, 1606 ToType, Context); 1607 return true; 1608 } 1609 const PointerType *FromTypePtr = FromType->getAs<PointerType>(); 1610 if (!FromTypePtr) 1611 return false; 1612 1613 QualType FromPointeeType = FromTypePtr->getPointeeType(); 1614 1615 // If the unqualified pointee types are the same, this can't be a 1616 // pointer conversion, so don't do all of the work below. 1617 if (Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) 1618 return false; 1619 1620 // An rvalue of type "pointer to cv T," where T is an object type, 1621 // can be converted to an rvalue of type "pointer to cv void" (C++ 1622 // 4.10p2). 1623 if (FromPointeeType->isIncompleteOrObjectType() && 1624 ToPointeeType->isVoidType()) { 1625 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1626 ToPointeeType, 1627 ToType, Context); 1628 return true; 1629 } 1630 1631 // When we're overloading in C, we allow a special kind of pointer 1632 // conversion for compatible-but-not-identical pointee types. 1633 if (!getLangOptions().CPlusPlus && 1634 Context.typesAreCompatible(FromPointeeType, ToPointeeType)) { 1635 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1636 ToPointeeType, 1637 ToType, Context); 1638 return true; 1639 } 1640 1641 // C++ [conv.ptr]p3: 1642 // 1643 // An rvalue of type "pointer to cv D," where D is a class type, 1644 // can be converted to an rvalue of type "pointer to cv B," where 1645 // B is a base class (clause 10) of D. If B is an inaccessible 1646 // (clause 11) or ambiguous (10.2) base class of D, a program that 1647 // necessitates this conversion is ill-formed. The result of the 1648 // conversion is a pointer to the base class sub-object of the 1649 // derived class object. The null pointer value is converted to 1650 // the null pointer value of the destination type. 1651 // 1652 // Note that we do not check for ambiguity or inaccessibility 1653 // here. That is handled by CheckPointerConversion. 1654 if (getLangOptions().CPlusPlus && 1655 FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 1656 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType) && 1657 !RequireCompleteType(From->getLocStart(), FromPointeeType, PDiag()) && 1658 IsDerivedFrom(FromPointeeType, ToPointeeType)) { 1659 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1660 ToPointeeType, 1661 ToType, Context); 1662 return true; 1663 } 1664 1665 if (FromPointeeType->isVectorType() && ToPointeeType->isVectorType() && 1666 Context.areCompatibleVectorTypes(FromPointeeType, ToPointeeType)) { 1667 ConvertedType = BuildSimilarlyQualifiedPointerType(FromTypePtr, 1668 ToPointeeType, 1669 ToType, Context); 1670 return true; 1671 } 1672 1673 return false; 1674} 1675 1676/// \brief Adopt the given qualifiers for the given type. 1677static QualType AdoptQualifiers(ASTContext &Context, QualType T, Qualifiers Qs){ 1678 Qualifiers TQs = T.getQualifiers(); 1679 1680 // Check whether qualifiers already match. 1681 if (TQs == Qs) 1682 return T; 1683 1684 if (Qs.compatiblyIncludes(TQs)) 1685 return Context.getQualifiedType(T, Qs); 1686 1687 return Context.getQualifiedType(T.getUnqualifiedType(), Qs); 1688} 1689 1690/// isObjCPointerConversion - Determines whether this is an 1691/// Objective-C pointer conversion. Subroutine of IsPointerConversion, 1692/// with the same arguments and return values. 1693bool Sema::isObjCPointerConversion(QualType FromType, QualType ToType, 1694 QualType& ConvertedType, 1695 bool &IncompatibleObjC) { 1696 if (!getLangOptions().ObjC1) 1697 return false; 1698 1699 // The set of qualifiers on the type we're converting from. 1700 Qualifiers FromQualifiers = FromType.getQualifiers(); 1701 1702 // First, we handle all conversions on ObjC object pointer types. 1703 const ObjCObjectPointerType* ToObjCPtr = 1704 ToType->getAs<ObjCObjectPointerType>(); 1705 const ObjCObjectPointerType *FromObjCPtr = 1706 FromType->getAs<ObjCObjectPointerType>(); 1707 1708 if (ToObjCPtr && FromObjCPtr) { 1709 // If the pointee types are the same (ignoring qualifications), 1710 // then this is not a pointer conversion. 1711 if (Context.hasSameUnqualifiedType(ToObjCPtr->getPointeeType(), 1712 FromObjCPtr->getPointeeType())) 1713 return false; 1714 1715 // Check for compatible 1716 // Objective C++: We're able to convert between "id" or "Class" and a 1717 // pointer to any interface (in both directions). 1718 if (ToObjCPtr->isObjCBuiltinType() && FromObjCPtr->isObjCBuiltinType()) { 1719 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1720 return true; 1721 } 1722 // Conversions with Objective-C's id<...>. 1723 if ((FromObjCPtr->isObjCQualifiedIdType() || 1724 ToObjCPtr->isObjCQualifiedIdType()) && 1725 Context.ObjCQualifiedIdTypesAreCompatible(ToType, FromType, 1726 /*compare=*/false)) { 1727 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1728 return true; 1729 } 1730 // Objective C++: We're able to convert from a pointer to an 1731 // interface to a pointer to a different interface. 1732 if (Context.canAssignObjCInterfaces(ToObjCPtr, FromObjCPtr)) { 1733 const ObjCInterfaceType* LHS = ToObjCPtr->getInterfaceType(); 1734 const ObjCInterfaceType* RHS = FromObjCPtr->getInterfaceType(); 1735 if (getLangOptions().CPlusPlus && LHS && RHS && 1736 !ToObjCPtr->getPointeeType().isAtLeastAsQualifiedAs( 1737 FromObjCPtr->getPointeeType())) 1738 return false; 1739 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 1740 ToObjCPtr->getPointeeType(), 1741 ToType, Context); 1742 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1743 return true; 1744 } 1745 1746 if (Context.canAssignObjCInterfaces(FromObjCPtr, ToObjCPtr)) { 1747 // Okay: this is some kind of implicit downcast of Objective-C 1748 // interfaces, which is permitted. However, we're going to 1749 // complain about it. 1750 IncompatibleObjC = true; 1751 ConvertedType = BuildSimilarlyQualifiedPointerType(FromObjCPtr, 1752 ToObjCPtr->getPointeeType(), 1753 ToType, Context); 1754 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1755 return true; 1756 } 1757 } 1758 // Beyond this point, both types need to be C pointers or block pointers. 1759 QualType ToPointeeType; 1760 if (const PointerType *ToCPtr = ToType->getAs<PointerType>()) 1761 ToPointeeType = ToCPtr->getPointeeType(); 1762 else if (const BlockPointerType *ToBlockPtr = 1763 ToType->getAs<BlockPointerType>()) { 1764 // Objective C++: We're able to convert from a pointer to any object 1765 // to a block pointer type. 1766 if (FromObjCPtr && FromObjCPtr->isObjCBuiltinType()) { 1767 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1768 return true; 1769 } 1770 ToPointeeType = ToBlockPtr->getPointeeType(); 1771 } 1772 else if (FromType->getAs<BlockPointerType>() && 1773 ToObjCPtr && ToObjCPtr->isObjCBuiltinType()) { 1774 // Objective C++: We're able to convert from a block pointer type to a 1775 // pointer to any object. 1776 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1777 return true; 1778 } 1779 else 1780 return false; 1781 1782 QualType FromPointeeType; 1783 if (const PointerType *FromCPtr = FromType->getAs<PointerType>()) 1784 FromPointeeType = FromCPtr->getPointeeType(); 1785 else if (const BlockPointerType *FromBlockPtr = 1786 FromType->getAs<BlockPointerType>()) 1787 FromPointeeType = FromBlockPtr->getPointeeType(); 1788 else 1789 return false; 1790 1791 // If we have pointers to pointers, recursively check whether this 1792 // is an Objective-C conversion. 1793 if (FromPointeeType->isPointerType() && ToPointeeType->isPointerType() && 1794 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1795 IncompatibleObjC)) { 1796 // We always complain about this conversion. 1797 IncompatibleObjC = true; 1798 ConvertedType = Context.getPointerType(ConvertedType); 1799 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1800 return true; 1801 } 1802 // Allow conversion of pointee being objective-c pointer to another one; 1803 // as in I* to id. 1804 if (FromPointeeType->getAs<ObjCObjectPointerType>() && 1805 ToPointeeType->getAs<ObjCObjectPointerType>() && 1806 isObjCPointerConversion(FromPointeeType, ToPointeeType, ConvertedType, 1807 IncompatibleObjC)) { 1808 ConvertedType = Context.getPointerType(ConvertedType); 1809 ConvertedType = AdoptQualifiers(Context, ConvertedType, FromQualifiers); 1810 return true; 1811 } 1812 1813 // If we have pointers to functions or blocks, check whether the only 1814 // differences in the argument and result types are in Objective-C 1815 // pointer conversions. If so, we permit the conversion (but 1816 // complain about it). 1817 const FunctionProtoType *FromFunctionType 1818 = FromPointeeType->getAs<FunctionProtoType>(); 1819 const FunctionProtoType *ToFunctionType 1820 = ToPointeeType->getAs<FunctionProtoType>(); 1821 if (FromFunctionType && ToFunctionType) { 1822 // If the function types are exactly the same, this isn't an 1823 // Objective-C pointer conversion. 1824 if (Context.getCanonicalType(FromPointeeType) 1825 == Context.getCanonicalType(ToPointeeType)) 1826 return false; 1827 1828 // Perform the quick checks that will tell us whether these 1829 // function types are obviously different. 1830 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 1831 FromFunctionType->isVariadic() != ToFunctionType->isVariadic() || 1832 FromFunctionType->getTypeQuals() != ToFunctionType->getTypeQuals()) 1833 return false; 1834 1835 bool HasObjCConversion = false; 1836 if (Context.getCanonicalType(FromFunctionType->getResultType()) 1837 == Context.getCanonicalType(ToFunctionType->getResultType())) { 1838 // Okay, the types match exactly. Nothing to do. 1839 } else if (isObjCPointerConversion(FromFunctionType->getResultType(), 1840 ToFunctionType->getResultType(), 1841 ConvertedType, IncompatibleObjC)) { 1842 // Okay, we have an Objective-C pointer conversion. 1843 HasObjCConversion = true; 1844 } else { 1845 // Function types are too different. Abort. 1846 return false; 1847 } 1848 1849 // Check argument types. 1850 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 1851 ArgIdx != NumArgs; ++ArgIdx) { 1852 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 1853 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 1854 if (Context.getCanonicalType(FromArgType) 1855 == Context.getCanonicalType(ToArgType)) { 1856 // Okay, the types match exactly. Nothing to do. 1857 } else if (isObjCPointerConversion(FromArgType, ToArgType, 1858 ConvertedType, IncompatibleObjC)) { 1859 // Okay, we have an Objective-C pointer conversion. 1860 HasObjCConversion = true; 1861 } else { 1862 // Argument types are too different. Abort. 1863 return false; 1864 } 1865 } 1866 1867 if (HasObjCConversion) { 1868 // We had an Objective-C conversion. Allow this pointer 1869 // conversion, but complain about it. 1870 ConvertedType = AdoptQualifiers(Context, ToType, FromQualifiers); 1871 IncompatibleObjC = true; 1872 return true; 1873 } 1874 } 1875 1876 return false; 1877} 1878 1879bool Sema::IsBlockPointerConversion(QualType FromType, QualType ToType, 1880 QualType& ConvertedType) { 1881 QualType ToPointeeType; 1882 if (const BlockPointerType *ToBlockPtr = 1883 ToType->getAs<BlockPointerType>()) 1884 ToPointeeType = ToBlockPtr->getPointeeType(); 1885 else 1886 return false; 1887 1888 QualType FromPointeeType; 1889 if (const BlockPointerType *FromBlockPtr = 1890 FromType->getAs<BlockPointerType>()) 1891 FromPointeeType = FromBlockPtr->getPointeeType(); 1892 else 1893 return false; 1894 // We have pointer to blocks, check whether the only 1895 // differences in the argument and result types are in Objective-C 1896 // pointer conversions. If so, we permit the conversion. 1897 1898 const FunctionProtoType *FromFunctionType 1899 = FromPointeeType->getAs<FunctionProtoType>(); 1900 const FunctionProtoType *ToFunctionType 1901 = ToPointeeType->getAs<FunctionProtoType>(); 1902 1903 if (!FromFunctionType || !ToFunctionType) 1904 return false; 1905 1906 if (Context.hasSameType(FromPointeeType, ToPointeeType)) 1907 return true; 1908 1909 // Perform the quick checks that will tell us whether these 1910 // function types are obviously different. 1911 if (FromFunctionType->getNumArgs() != ToFunctionType->getNumArgs() || 1912 FromFunctionType->isVariadic() != ToFunctionType->isVariadic()) 1913 return false; 1914 1915 FunctionType::ExtInfo FromEInfo = FromFunctionType->getExtInfo(); 1916 FunctionType::ExtInfo ToEInfo = ToFunctionType->getExtInfo(); 1917 if (FromEInfo != ToEInfo) 1918 return false; 1919 1920 bool IncompatibleObjC = false; 1921 if (Context.hasSameType(FromFunctionType->getResultType(), 1922 ToFunctionType->getResultType())) { 1923 // Okay, the types match exactly. Nothing to do. 1924 } else { 1925 QualType RHS = FromFunctionType->getResultType(); 1926 QualType LHS = ToFunctionType->getResultType(); 1927 if ((!getLangOptions().CPlusPlus || !RHS->isRecordType()) && 1928 !RHS.hasQualifiers() && LHS.hasQualifiers()) 1929 LHS = LHS.getUnqualifiedType(); 1930 1931 if (Context.hasSameType(RHS,LHS)) { 1932 // OK exact match. 1933 } else if (isObjCPointerConversion(RHS, LHS, 1934 ConvertedType, IncompatibleObjC)) { 1935 if (IncompatibleObjC) 1936 return false; 1937 // Okay, we have an Objective-C pointer conversion. 1938 } 1939 else 1940 return false; 1941 } 1942 1943 // Check argument types. 1944 for (unsigned ArgIdx = 0, NumArgs = FromFunctionType->getNumArgs(); 1945 ArgIdx != NumArgs; ++ArgIdx) { 1946 IncompatibleObjC = false; 1947 QualType FromArgType = FromFunctionType->getArgType(ArgIdx); 1948 QualType ToArgType = ToFunctionType->getArgType(ArgIdx); 1949 if (Context.hasSameType(FromArgType, ToArgType)) { 1950 // Okay, the types match exactly. Nothing to do. 1951 } else if (isObjCPointerConversion(ToArgType, FromArgType, 1952 ConvertedType, IncompatibleObjC)) { 1953 if (IncompatibleObjC) 1954 return false; 1955 // Okay, we have an Objective-C pointer conversion. 1956 } else 1957 // Argument types are too different. Abort. 1958 return false; 1959 } 1960 ConvertedType = ToType; 1961 return true; 1962} 1963 1964/// FunctionArgTypesAreEqual - This routine checks two function proto types 1965/// for equlity of their argument types. Caller has already checked that 1966/// they have same number of arguments. This routine assumes that Objective-C 1967/// pointer types which only differ in their protocol qualifiers are equal. 1968bool Sema::FunctionArgTypesAreEqual(const FunctionProtoType *OldType, 1969 const FunctionProtoType *NewType) { 1970 if (!getLangOptions().ObjC1) 1971 return std::equal(OldType->arg_type_begin(), OldType->arg_type_end(), 1972 NewType->arg_type_begin()); 1973 1974 for (FunctionProtoType::arg_type_iterator O = OldType->arg_type_begin(), 1975 N = NewType->arg_type_begin(), 1976 E = OldType->arg_type_end(); O && (O != E); ++O, ++N) { 1977 QualType ToType = (*O); 1978 QualType FromType = (*N); 1979 if (ToType != FromType) { 1980 if (const PointerType *PTTo = ToType->getAs<PointerType>()) { 1981 if (const PointerType *PTFr = FromType->getAs<PointerType>()) 1982 if ((PTTo->getPointeeType()->isObjCQualifiedIdType() && 1983 PTFr->getPointeeType()->isObjCQualifiedIdType()) || 1984 (PTTo->getPointeeType()->isObjCQualifiedClassType() && 1985 PTFr->getPointeeType()->isObjCQualifiedClassType())) 1986 continue; 1987 } 1988 else if (const ObjCObjectPointerType *PTTo = 1989 ToType->getAs<ObjCObjectPointerType>()) { 1990 if (const ObjCObjectPointerType *PTFr = 1991 FromType->getAs<ObjCObjectPointerType>()) 1992 if (PTTo->getInterfaceDecl() == PTFr->getInterfaceDecl()) 1993 continue; 1994 } 1995 return false; 1996 } 1997 } 1998 return true; 1999} 2000 2001/// CheckPointerConversion - Check the pointer conversion from the 2002/// expression From to the type ToType. This routine checks for 2003/// ambiguous or inaccessible derived-to-base pointer 2004/// conversions for which IsPointerConversion has already returned 2005/// true. It returns true and produces a diagnostic if there was an 2006/// error, or returns false otherwise. 2007bool Sema::CheckPointerConversion(Expr *From, QualType ToType, 2008 CastKind &Kind, 2009 CXXCastPath& BasePath, 2010 bool IgnoreBaseAccess) { 2011 QualType FromType = From->getType(); 2012 bool IsCStyleOrFunctionalCast = IgnoreBaseAccess; 2013 2014 Kind = CK_BitCast; 2015 2016 if (!IsCStyleOrFunctionalCast && 2017 Context.hasSameUnqualifiedType(From->getType(), Context.BoolTy) && 2018 From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNotNull)) 2019 DiagRuntimeBehavior(From->getExprLoc(), From, 2020 PDiag(diag::warn_impcast_bool_to_null_pointer) 2021 << ToType << From->getSourceRange()); 2022 2023 if (const PointerType *FromPtrType = FromType->getAs<PointerType>()) 2024 if (const PointerType *ToPtrType = ToType->getAs<PointerType>()) { 2025 QualType FromPointeeType = FromPtrType->getPointeeType(), 2026 ToPointeeType = ToPtrType->getPointeeType(); 2027 2028 if (FromPointeeType->isRecordType() && ToPointeeType->isRecordType() && 2029 !Context.hasSameUnqualifiedType(FromPointeeType, ToPointeeType)) { 2030 // We must have a derived-to-base conversion. Check an 2031 // ambiguous or inaccessible conversion. 2032 if (CheckDerivedToBaseConversion(FromPointeeType, ToPointeeType, 2033 From->getExprLoc(), 2034 From->getSourceRange(), &BasePath, 2035 IgnoreBaseAccess)) 2036 return true; 2037 2038 // The conversion was successful. 2039 Kind = CK_DerivedToBase; 2040 } 2041 } 2042 if (const ObjCObjectPointerType *FromPtrType = 2043 FromType->getAs<ObjCObjectPointerType>()) { 2044 if (const ObjCObjectPointerType *ToPtrType = 2045 ToType->getAs<ObjCObjectPointerType>()) { 2046 // Objective-C++ conversions are always okay. 2047 // FIXME: We should have a different class of conversions for the 2048 // Objective-C++ implicit conversions. 2049 if (FromPtrType->isObjCBuiltinType() || ToPtrType->isObjCBuiltinType()) 2050 return false; 2051 } 2052 } 2053 2054 // We shouldn't fall into this case unless it's valid for other 2055 // reasons. 2056 if (From->isNullPointerConstant(Context, Expr::NPC_ValueDependentIsNull)) 2057 Kind = CK_NullToPointer; 2058 2059 return false; 2060} 2061 2062/// IsMemberPointerConversion - Determines whether the conversion of the 2063/// expression From, which has the (possibly adjusted) type FromType, can be 2064/// converted to the type ToType via a member pointer conversion (C++ 4.11). 2065/// If so, returns true and places the converted type (that might differ from 2066/// ToType in its cv-qualifiers at some level) into ConvertedType. 2067bool Sema::IsMemberPointerConversion(Expr *From, QualType FromType, 2068 QualType ToType, 2069 bool InOverloadResolution, 2070 QualType &ConvertedType) { 2071 const MemberPointerType *ToTypePtr = ToType->getAs<MemberPointerType>(); 2072 if (!ToTypePtr) 2073 return false; 2074 2075 // A null pointer constant can be converted to a member pointer (C++ 4.11p1) 2076 if (From->isNullPointerConstant(Context, 2077 InOverloadResolution? Expr::NPC_ValueDependentIsNotNull 2078 : Expr::NPC_ValueDependentIsNull)) { 2079 ConvertedType = ToType; 2080 return true; 2081 } 2082 2083 // Otherwise, both types have to be member pointers. 2084 const MemberPointerType *FromTypePtr = FromType->getAs<MemberPointerType>(); 2085 if (!FromTypePtr) 2086 return false; 2087 2088 // A pointer to member of B can be converted to a pointer to member of D, 2089 // where D is derived from B (C++ 4.11p2). 2090 QualType FromClass(FromTypePtr->getClass(), 0); 2091 QualType ToClass(ToTypePtr->getClass(), 0); 2092 2093 if (!Context.hasSameUnqualifiedType(FromClass, ToClass) && 2094 !RequireCompleteType(From->getLocStart(), ToClass, PDiag()) && 2095 IsDerivedFrom(ToClass, FromClass)) { 2096 ConvertedType = Context.getMemberPointerType(FromTypePtr->getPointeeType(), 2097 ToClass.getTypePtr()); 2098 return true; 2099 } 2100 2101 return false; 2102} 2103 2104/// CheckMemberPointerConversion - Check the member pointer conversion from the 2105/// expression From to the type ToType. This routine checks for ambiguous or 2106/// virtual or inaccessible base-to-derived member pointer conversions 2107/// for which IsMemberPointerConversion has already returned true. It returns 2108/// true and produces a diagnostic if there was an error, or returns false 2109/// otherwise. 2110bool Sema::CheckMemberPointerConversion(Expr *From, QualType ToType, 2111 CastKind &Kind, 2112 CXXCastPath &BasePath, 2113 bool IgnoreBaseAccess) { 2114 QualType FromType = From->getType(); 2115 const MemberPointerType *FromPtrType = FromType->getAs<MemberPointerType>(); 2116 if (!FromPtrType) { 2117 // This must be a null pointer to member pointer conversion 2118 assert(From->isNullPointerConstant(Context, 2119 Expr::NPC_ValueDependentIsNull) && 2120 "Expr must be null pointer constant!"); 2121 Kind = CK_NullToMemberPointer; 2122 return false; 2123 } 2124 2125 const MemberPointerType *ToPtrType = ToType->getAs<MemberPointerType>(); 2126 assert(ToPtrType && "No member pointer cast has a target type " 2127 "that is not a member pointer."); 2128 2129 QualType FromClass = QualType(FromPtrType->getClass(), 0); 2130 QualType ToClass = QualType(ToPtrType->getClass(), 0); 2131 2132 // FIXME: What about dependent types? 2133 assert(FromClass->isRecordType() && "Pointer into non-class."); 2134 assert(ToClass->isRecordType() && "Pointer into non-class."); 2135 2136 CXXBasePaths Paths(/*FindAmbiguities=*/true, /*RecordPaths=*/true, 2137 /*DetectVirtual=*/true); 2138 bool DerivationOkay = IsDerivedFrom(ToClass, FromClass, Paths); 2139 assert(DerivationOkay && 2140 "Should not have been called if derivation isn't OK."); 2141 (void)DerivationOkay; 2142 2143 if (Paths.isAmbiguous(Context.getCanonicalType(FromClass). 2144 getUnqualifiedType())) { 2145 std::string PathDisplayStr = getAmbiguousPathsDisplayString(Paths); 2146 Diag(From->getExprLoc(), diag::err_ambiguous_memptr_conv) 2147 << 0 << FromClass << ToClass << PathDisplayStr << From->getSourceRange(); 2148 return true; 2149 } 2150 2151 if (const RecordType *VBase = Paths.getDetectedVirtual()) { 2152 Diag(From->getExprLoc(), diag::err_memptr_conv_via_virtual) 2153 << FromClass << ToClass << QualType(VBase, 0) 2154 << From->getSourceRange(); 2155 return true; 2156 } 2157 2158 if (!IgnoreBaseAccess) 2159 CheckBaseClassAccess(From->getExprLoc(), FromClass, ToClass, 2160 Paths.front(), 2161 diag::err_downcast_from_inaccessible_base); 2162 2163 // Must be a base to derived member conversion. 2164 BuildBasePathArray(Paths, BasePath); 2165 Kind = CK_BaseToDerivedMemberPointer; 2166 return false; 2167} 2168 2169/// IsQualificationConversion - Determines whether the conversion from 2170/// an rvalue of type FromType to ToType is a qualification conversion 2171/// (C++ 4.4). 2172bool 2173Sema::IsQualificationConversion(QualType FromType, QualType ToType, 2174 bool CStyle) { 2175 FromType = Context.getCanonicalType(FromType); 2176 ToType = Context.getCanonicalType(ToType); 2177 2178 // If FromType and ToType are the same type, this is not a 2179 // qualification conversion. 2180 if (FromType.getUnqualifiedType() == ToType.getUnqualifiedType()) 2181 return false; 2182 2183 // (C++ 4.4p4): 2184 // A conversion can add cv-qualifiers at levels other than the first 2185 // in multi-level pointers, subject to the following rules: [...] 2186 bool PreviousToQualsIncludeConst = true; 2187 bool UnwrappedAnyPointer = false; 2188 while (Context.UnwrapSimilarPointerTypes(FromType, ToType)) { 2189 // Within each iteration of the loop, we check the qualifiers to 2190 // determine if this still looks like a qualification 2191 // conversion. Then, if all is well, we unwrap one more level of 2192 // pointers or pointers-to-members and do it all again 2193 // until there are no more pointers or pointers-to-members left to 2194 // unwrap. 2195 UnwrappedAnyPointer = true; 2196 2197 Qualifiers FromQuals = FromType.getQualifiers(); 2198 Qualifiers ToQuals = ToType.getQualifiers(); 2199 2200 // -- for every j > 0, if const is in cv 1,j then const is in cv 2201 // 2,j, and similarly for volatile. 2202 if (!CStyle && !ToQuals.compatiblyIncludes(FromQuals)) 2203 return false; 2204 2205 // -- if the cv 1,j and cv 2,j are different, then const is in 2206 // every cv for 0 < k < j. 2207 if (!CStyle && FromQuals.getCVRQualifiers() != ToQuals.getCVRQualifiers() 2208 && !PreviousToQualsIncludeConst) 2209 return false; 2210 2211 // Keep track of whether all prior cv-qualifiers in the "to" type 2212 // include const. 2213 PreviousToQualsIncludeConst 2214 = PreviousToQualsIncludeConst && ToQuals.hasConst(); 2215 } 2216 2217 // We are left with FromType and ToType being the pointee types 2218 // after unwrapping the original FromType and ToType the same number 2219 // of types. If we unwrapped any pointers, and if FromType and 2220 // ToType have the same unqualified type (since we checked 2221 // qualifiers above), then this is a qualification conversion. 2222 return UnwrappedAnyPointer && Context.hasSameUnqualifiedType(FromType,ToType); 2223} 2224 2225/// Determines whether there is a user-defined conversion sequence 2226/// (C++ [over.ics.user]) that converts expression From to the type 2227/// ToType. If such a conversion exists, User will contain the 2228/// user-defined conversion sequence that performs such a conversion 2229/// and this routine will return true. Otherwise, this routine returns 2230/// false and User is unspecified. 2231/// 2232/// \param AllowExplicit true if the conversion should consider C++0x 2233/// "explicit" conversion functions as well as non-explicit conversion 2234/// functions (C++0x [class.conv.fct]p2). 2235static OverloadingResult 2236IsUserDefinedConversion(Sema &S, Expr *From, QualType ToType, 2237 UserDefinedConversionSequence& User, 2238 OverloadCandidateSet& CandidateSet, 2239 bool AllowExplicit) { 2240 // Whether we will only visit constructors. 2241 bool ConstructorsOnly = false; 2242 2243 // If the type we are conversion to is a class type, enumerate its 2244 // constructors. 2245 if (const RecordType *ToRecordType = ToType->getAs<RecordType>()) { 2246 // C++ [over.match.ctor]p1: 2247 // When objects of class type are direct-initialized (8.5), or 2248 // copy-initialized from an expression of the same or a 2249 // derived class type (8.5), overload resolution selects the 2250 // constructor. [...] For copy-initialization, the candidate 2251 // functions are all the converting constructors (12.3.1) of 2252 // that class. The argument list is the expression-list within 2253 // the parentheses of the initializer. 2254 if (S.Context.hasSameUnqualifiedType(ToType, From->getType()) || 2255 (From->getType()->getAs<RecordType>() && 2256 S.IsDerivedFrom(From->getType(), ToType))) 2257 ConstructorsOnly = true; 2258 2259 S.RequireCompleteType(From->getLocStart(), ToType, S.PDiag()); 2260 // RequireCompleteType may have returned true due to some invalid decl 2261 // during template instantiation, but ToType may be complete enough now 2262 // to try to recover. 2263 if (ToType->isIncompleteType()) { 2264 // We're not going to find any constructors. 2265 } else if (CXXRecordDecl *ToRecordDecl 2266 = dyn_cast<CXXRecordDecl>(ToRecordType->getDecl())) { 2267 DeclContext::lookup_iterator Con, ConEnd; 2268 for (llvm::tie(Con, ConEnd) = S.LookupConstructors(ToRecordDecl); 2269 Con != ConEnd; ++Con) { 2270 NamedDecl *D = *Con; 2271 DeclAccessPair FoundDecl = DeclAccessPair::make(D, D->getAccess()); 2272 2273 // Find the constructor (which may be a template). 2274 CXXConstructorDecl *Constructor = 0; 2275 FunctionTemplateDecl *ConstructorTmpl 2276 = dyn_cast<FunctionTemplateDecl>(D); 2277 if (ConstructorTmpl) 2278 Constructor 2279 = cast<CXXConstructorDecl>(ConstructorTmpl->getTemplatedDecl()); 2280 else 2281 Constructor = cast<CXXConstructorDecl>(D); 2282 2283 if (!Constructor->isInvalidDecl() && 2284 Constructor->isConvertingConstructor(AllowExplicit)) { 2285 if (ConstructorTmpl) 2286 S.AddTemplateOverloadCandidate(ConstructorTmpl, FoundDecl, 2287 /*ExplicitArgs*/ 0, 2288 &From, 1, CandidateSet, 2289 /*SuppressUserConversions=*/ 2290 !ConstructorsOnly); 2291 else 2292 // Allow one user-defined conversion when user specifies a 2293 // From->ToType conversion via an static cast (c-style, etc). 2294 S.AddOverloadCandidate(Constructor, FoundDecl, 2295 &From, 1, CandidateSet, 2296 /*SuppressUserConversions=*/ 2297 !ConstructorsOnly); 2298 } 2299 } 2300 } 2301 } 2302 2303 // Enumerate conversion functions, if we're allowed to. 2304 if (ConstructorsOnly) { 2305 } else if (S.RequireCompleteType(From->getLocStart(), From->getType(), 2306 S.PDiag(0) << From->getSourceRange())) { 2307 // No conversion functions from incomplete types. 2308 } else if (const RecordType *FromRecordType 2309 = From->getType()->getAs<RecordType>()) { 2310 if (CXXRecordDecl *FromRecordDecl 2311 = dyn_cast<CXXRecordDecl>(FromRecordType->getDecl())) { 2312 // Add all of the conversion functions as candidates. 2313 const UnresolvedSetImpl *Conversions 2314 = FromRecordDecl->getVisibleConversionFunctions(); 2315 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 2316 E = Conversions->end(); I != E; ++I) { 2317 DeclAccessPair FoundDecl = I.getPair(); 2318 NamedDecl *D = FoundDecl.getDecl(); 2319 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 2320 if (isa<UsingShadowDecl>(D)) 2321 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 2322 2323 CXXConversionDecl *Conv; 2324 FunctionTemplateDecl *ConvTemplate; 2325 if ((ConvTemplate = dyn_cast<FunctionTemplateDecl>(D))) 2326 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 2327 else 2328 Conv = cast<CXXConversionDecl>(D); 2329 2330 if (AllowExplicit || !Conv->isExplicit()) { 2331 if (ConvTemplate) 2332 S.AddTemplateConversionCandidate(ConvTemplate, FoundDecl, 2333 ActingContext, From, ToType, 2334 CandidateSet); 2335 else 2336 S.AddConversionCandidate(Conv, FoundDecl, ActingContext, 2337 From, ToType, CandidateSet); 2338 } 2339 } 2340 } 2341 } 2342 2343 OverloadCandidateSet::iterator Best; 2344 switch (CandidateSet.BestViableFunction(S, From->getLocStart(), Best, true)) { 2345 case OR_Success: 2346 // Record the standard conversion we used and the conversion function. 2347 if (CXXConstructorDecl *Constructor 2348 = dyn_cast<CXXConstructorDecl>(Best->Function)) { 2349 S.MarkDeclarationReferenced(From->getLocStart(), Constructor); 2350 2351 // C++ [over.ics.user]p1: 2352 // If the user-defined conversion is specified by a 2353 // constructor (12.3.1), the initial standard conversion 2354 // sequence converts the source type to the type required by 2355 // the argument of the constructor. 2356 // 2357 QualType ThisType = Constructor->getThisType(S.Context); 2358 if (Best->Conversions[0].isEllipsis()) 2359 User.EllipsisConversion = true; 2360 else { 2361 User.Before = Best->Conversions[0].Standard; 2362 User.EllipsisConversion = false; 2363 } 2364 User.ConversionFunction = Constructor; 2365 User.FoundConversionFunction = Best->FoundDecl.getDecl(); 2366 User.After.setAsIdentityConversion(); 2367 User.After.setFromType(ThisType->getAs<PointerType>()->getPointeeType()); 2368 User.After.setAllToTypes(ToType); 2369 return OR_Success; 2370 } else if (CXXConversionDecl *Conversion 2371 = dyn_cast<CXXConversionDecl>(Best->Function)) { 2372 S.MarkDeclarationReferenced(From->getLocStart(), Conversion); 2373 2374 // C++ [over.ics.user]p1: 2375 // 2376 // [...] If the user-defined conversion is specified by a 2377 // conversion function (12.3.2), the initial standard 2378 // conversion sequence converts the source type to the 2379 // implicit object parameter of the conversion function. 2380 User.Before = Best->Conversions[0].Standard; 2381 User.ConversionFunction = Conversion; 2382 User.FoundConversionFunction = Best->FoundDecl.getDecl(); 2383 User.EllipsisConversion = false; 2384 2385 // C++ [over.ics.user]p2: 2386 // The second standard conversion sequence converts the 2387 // result of the user-defined conversion to the target type 2388 // for the sequence. Since an implicit conversion sequence 2389 // is an initialization, the special rules for 2390 // initialization by user-defined conversion apply when 2391 // selecting the best user-defined conversion for a 2392 // user-defined conversion sequence (see 13.3.3 and 2393 // 13.3.3.1). 2394 User.After = Best->FinalConversion; 2395 return OR_Success; 2396 } else { 2397 llvm_unreachable("Not a constructor or conversion function?"); 2398 return OR_No_Viable_Function; 2399 } 2400 2401 case OR_No_Viable_Function: 2402 return OR_No_Viable_Function; 2403 case OR_Deleted: 2404 // No conversion here! We're done. 2405 return OR_Deleted; 2406 2407 case OR_Ambiguous: 2408 return OR_Ambiguous; 2409 } 2410 2411 return OR_No_Viable_Function; 2412} 2413 2414bool 2415Sema::DiagnoseMultipleUserDefinedConversion(Expr *From, QualType ToType) { 2416 ImplicitConversionSequence ICS; 2417 OverloadCandidateSet CandidateSet(From->getExprLoc()); 2418 OverloadingResult OvResult = 2419 IsUserDefinedConversion(*this, From, ToType, ICS.UserDefined, 2420 CandidateSet, false); 2421 if (OvResult == OR_Ambiguous) 2422 Diag(From->getSourceRange().getBegin(), 2423 diag::err_typecheck_ambiguous_condition) 2424 << From->getType() << ToType << From->getSourceRange(); 2425 else if (OvResult == OR_No_Viable_Function && !CandidateSet.empty()) 2426 Diag(From->getSourceRange().getBegin(), 2427 diag::err_typecheck_nonviable_condition) 2428 << From->getType() << ToType << From->getSourceRange(); 2429 else 2430 return false; 2431 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &From, 1); 2432 return true; 2433} 2434 2435/// CompareImplicitConversionSequences - Compare two implicit 2436/// conversion sequences to determine whether one is better than the 2437/// other or if they are indistinguishable (C++ 13.3.3.2). 2438static ImplicitConversionSequence::CompareKind 2439CompareImplicitConversionSequences(Sema &S, 2440 const ImplicitConversionSequence& ICS1, 2441 const ImplicitConversionSequence& ICS2) 2442{ 2443 // (C++ 13.3.3.2p2): When comparing the basic forms of implicit 2444 // conversion sequences (as defined in 13.3.3.1) 2445 // -- a standard conversion sequence (13.3.3.1.1) is a better 2446 // conversion sequence than a user-defined conversion sequence or 2447 // an ellipsis conversion sequence, and 2448 // -- a user-defined conversion sequence (13.3.3.1.2) is a better 2449 // conversion sequence than an ellipsis conversion sequence 2450 // (13.3.3.1.3). 2451 // 2452 // C++0x [over.best.ics]p10: 2453 // For the purpose of ranking implicit conversion sequences as 2454 // described in 13.3.3.2, the ambiguous conversion sequence is 2455 // treated as a user-defined sequence that is indistinguishable 2456 // from any other user-defined conversion sequence. 2457 if (ICS1.getKindRank() < ICS2.getKindRank()) 2458 return ImplicitConversionSequence::Better; 2459 else if (ICS2.getKindRank() < ICS1.getKindRank()) 2460 return ImplicitConversionSequence::Worse; 2461 2462 // The following checks require both conversion sequences to be of 2463 // the same kind. 2464 if (ICS1.getKind() != ICS2.getKind()) 2465 return ImplicitConversionSequence::Indistinguishable; 2466 2467 // Two implicit conversion sequences of the same form are 2468 // indistinguishable conversion sequences unless one of the 2469 // following rules apply: (C++ 13.3.3.2p3): 2470 if (ICS1.isStandard()) 2471 return CompareStandardConversionSequences(S, ICS1.Standard, ICS2.Standard); 2472 else if (ICS1.isUserDefined()) { 2473 // User-defined conversion sequence U1 is a better conversion 2474 // sequence than another user-defined conversion sequence U2 if 2475 // they contain the same user-defined conversion function or 2476 // constructor and if the second standard conversion sequence of 2477 // U1 is better than the second standard conversion sequence of 2478 // U2 (C++ 13.3.3.2p3). 2479 if (ICS1.UserDefined.ConversionFunction == 2480 ICS2.UserDefined.ConversionFunction) 2481 return CompareStandardConversionSequences(S, 2482 ICS1.UserDefined.After, 2483 ICS2.UserDefined.After); 2484 } 2485 2486 return ImplicitConversionSequence::Indistinguishable; 2487} 2488 2489static bool hasSimilarType(ASTContext &Context, QualType T1, QualType T2) { 2490 while (Context.UnwrapSimilarPointerTypes(T1, T2)) { 2491 Qualifiers Quals; 2492 T1 = Context.getUnqualifiedArrayType(T1, Quals); 2493 T2 = Context.getUnqualifiedArrayType(T2, Quals); 2494 } 2495 2496 return Context.hasSameUnqualifiedType(T1, T2); 2497} 2498 2499// Per 13.3.3.2p3, compare the given standard conversion sequences to 2500// determine if one is a proper subset of the other. 2501static ImplicitConversionSequence::CompareKind 2502compareStandardConversionSubsets(ASTContext &Context, 2503 const StandardConversionSequence& SCS1, 2504 const StandardConversionSequence& SCS2) { 2505 ImplicitConversionSequence::CompareKind Result 2506 = ImplicitConversionSequence::Indistinguishable; 2507 2508 // the identity conversion sequence is considered to be a subsequence of 2509 // any non-identity conversion sequence 2510 if (SCS1.ReferenceBinding == SCS2.ReferenceBinding) { 2511 if (SCS1.isIdentityConversion() && !SCS2.isIdentityConversion()) 2512 return ImplicitConversionSequence::Better; 2513 else if (!SCS1.isIdentityConversion() && SCS2.isIdentityConversion()) 2514 return ImplicitConversionSequence::Worse; 2515 } 2516 2517 if (SCS1.Second != SCS2.Second) { 2518 if (SCS1.Second == ICK_Identity) 2519 Result = ImplicitConversionSequence::Better; 2520 else if (SCS2.Second == ICK_Identity) 2521 Result = ImplicitConversionSequence::Worse; 2522 else 2523 return ImplicitConversionSequence::Indistinguishable; 2524 } else if (!hasSimilarType(Context, SCS1.getToType(1), SCS2.getToType(1))) 2525 return ImplicitConversionSequence::Indistinguishable; 2526 2527 if (SCS1.Third == SCS2.Third) { 2528 return Context.hasSameType(SCS1.getToType(2), SCS2.getToType(2))? Result 2529 : ImplicitConversionSequence::Indistinguishable; 2530 } 2531 2532 if (SCS1.Third == ICK_Identity) 2533 return Result == ImplicitConversionSequence::Worse 2534 ? ImplicitConversionSequence::Indistinguishable 2535 : ImplicitConversionSequence::Better; 2536 2537 if (SCS2.Third == ICK_Identity) 2538 return Result == ImplicitConversionSequence::Better 2539 ? ImplicitConversionSequence::Indistinguishable 2540 : ImplicitConversionSequence::Worse; 2541 2542 return ImplicitConversionSequence::Indistinguishable; 2543} 2544 2545/// \brief Determine whether one of the given reference bindings is better 2546/// than the other based on what kind of bindings they are. 2547static bool isBetterReferenceBindingKind(const StandardConversionSequence &SCS1, 2548 const StandardConversionSequence &SCS2) { 2549 // C++0x [over.ics.rank]p3b4: 2550 // -- S1 and S2 are reference bindings (8.5.3) and neither refers to an 2551 // implicit object parameter of a non-static member function declared 2552 // without a ref-qualifier, and *either* S1 binds an rvalue reference 2553 // to an rvalue and S2 binds an lvalue reference *or S1 binds an 2554 // lvalue reference to a function lvalue and S2 binds an rvalue 2555 // reference*. 2556 // 2557 // FIXME: Rvalue references. We're going rogue with the above edits, 2558 // because the semantics in the current C++0x working paper (N3225 at the 2559 // time of this writing) break the standard definition of std::forward 2560 // and std::reference_wrapper when dealing with references to functions. 2561 // Proposed wording changes submitted to CWG for consideration. 2562 if (SCS1.BindsImplicitObjectArgumentWithoutRefQualifier || 2563 SCS2.BindsImplicitObjectArgumentWithoutRefQualifier) 2564 return false; 2565 2566 return (!SCS1.IsLvalueReference && SCS1.BindsToRvalue && 2567 SCS2.IsLvalueReference) || 2568 (SCS1.IsLvalueReference && SCS1.BindsToFunctionLvalue && 2569 !SCS2.IsLvalueReference); 2570} 2571 2572/// CompareStandardConversionSequences - Compare two standard 2573/// conversion sequences to determine whether one is better than the 2574/// other or if they are indistinguishable (C++ 13.3.3.2p3). 2575static ImplicitConversionSequence::CompareKind 2576CompareStandardConversionSequences(Sema &S, 2577 const StandardConversionSequence& SCS1, 2578 const StandardConversionSequence& SCS2) 2579{ 2580 // Standard conversion sequence S1 is a better conversion sequence 2581 // than standard conversion sequence S2 if (C++ 13.3.3.2p3): 2582 2583 // -- S1 is a proper subsequence of S2 (comparing the conversion 2584 // sequences in the canonical form defined by 13.3.3.1.1, 2585 // excluding any Lvalue Transformation; the identity conversion 2586 // sequence is considered to be a subsequence of any 2587 // non-identity conversion sequence) or, if not that, 2588 if (ImplicitConversionSequence::CompareKind CK 2589 = compareStandardConversionSubsets(S.Context, SCS1, SCS2)) 2590 return CK; 2591 2592 // -- the rank of S1 is better than the rank of S2 (by the rules 2593 // defined below), or, if not that, 2594 ImplicitConversionRank Rank1 = SCS1.getRank(); 2595 ImplicitConversionRank Rank2 = SCS2.getRank(); 2596 if (Rank1 < Rank2) 2597 return ImplicitConversionSequence::Better; 2598 else if (Rank2 < Rank1) 2599 return ImplicitConversionSequence::Worse; 2600 2601 // (C++ 13.3.3.2p4): Two conversion sequences with the same rank 2602 // are indistinguishable unless one of the following rules 2603 // applies: 2604 2605 // A conversion that is not a conversion of a pointer, or 2606 // pointer to member, to bool is better than another conversion 2607 // that is such a conversion. 2608 if (SCS1.isPointerConversionToBool() != SCS2.isPointerConversionToBool()) 2609 return SCS2.isPointerConversionToBool() 2610 ? ImplicitConversionSequence::Better 2611 : ImplicitConversionSequence::Worse; 2612 2613 // C++ [over.ics.rank]p4b2: 2614 // 2615 // If class B is derived directly or indirectly from class A, 2616 // conversion of B* to A* is better than conversion of B* to 2617 // void*, and conversion of A* to void* is better than conversion 2618 // of B* to void*. 2619 bool SCS1ConvertsToVoid 2620 = SCS1.isPointerConversionToVoidPointer(S.Context); 2621 bool SCS2ConvertsToVoid 2622 = SCS2.isPointerConversionToVoidPointer(S.Context); 2623 if (SCS1ConvertsToVoid != SCS2ConvertsToVoid) { 2624 // Exactly one of the conversion sequences is a conversion to 2625 // a void pointer; it's the worse conversion. 2626 return SCS2ConvertsToVoid ? ImplicitConversionSequence::Better 2627 : ImplicitConversionSequence::Worse; 2628 } else if (!SCS1ConvertsToVoid && !SCS2ConvertsToVoid) { 2629 // Neither conversion sequence converts to a void pointer; compare 2630 // their derived-to-base conversions. 2631 if (ImplicitConversionSequence::CompareKind DerivedCK 2632 = CompareDerivedToBaseConversions(S, SCS1, SCS2)) 2633 return DerivedCK; 2634 } else if (SCS1ConvertsToVoid && SCS2ConvertsToVoid && 2635 !S.Context.hasSameType(SCS1.getFromType(), SCS2.getFromType())) { 2636 // Both conversion sequences are conversions to void 2637 // pointers. Compare the source types to determine if there's an 2638 // inheritance relationship in their sources. 2639 QualType FromType1 = SCS1.getFromType(); 2640 QualType FromType2 = SCS2.getFromType(); 2641 2642 // Adjust the types we're converting from via the array-to-pointer 2643 // conversion, if we need to. 2644 if (SCS1.First == ICK_Array_To_Pointer) 2645 FromType1 = S.Context.getArrayDecayedType(FromType1); 2646 if (SCS2.First == ICK_Array_To_Pointer) 2647 FromType2 = S.Context.getArrayDecayedType(FromType2); 2648 2649 QualType FromPointee1 = FromType1->getPointeeType().getUnqualifiedType(); 2650 QualType FromPointee2 = FromType2->getPointeeType().getUnqualifiedType(); 2651 2652 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 2653 return ImplicitConversionSequence::Better; 2654 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 2655 return ImplicitConversionSequence::Worse; 2656 2657 // Objective-C++: If one interface is more specific than the 2658 // other, it is the better one. 2659 const ObjCObjectPointerType* FromObjCPtr1 2660 = FromType1->getAs<ObjCObjectPointerType>(); 2661 const ObjCObjectPointerType* FromObjCPtr2 2662 = FromType2->getAs<ObjCObjectPointerType>(); 2663 if (FromObjCPtr1 && FromObjCPtr2) { 2664 bool AssignLeft = S.Context.canAssignObjCInterfaces(FromObjCPtr1, 2665 FromObjCPtr2); 2666 bool AssignRight = S.Context.canAssignObjCInterfaces(FromObjCPtr2, 2667 FromObjCPtr1); 2668 if (AssignLeft != AssignRight) { 2669 return AssignLeft? ImplicitConversionSequence::Better 2670 : ImplicitConversionSequence::Worse; 2671 } 2672 } 2673 } 2674 2675 // Compare based on qualification conversions (C++ 13.3.3.2p3, 2676 // bullet 3). 2677 if (ImplicitConversionSequence::CompareKind QualCK 2678 = CompareQualificationConversions(S, SCS1, SCS2)) 2679 return QualCK; 2680 2681 if (SCS1.ReferenceBinding && SCS2.ReferenceBinding) { 2682 // Check for a better reference binding based on the kind of bindings. 2683 if (isBetterReferenceBindingKind(SCS1, SCS2)) 2684 return ImplicitConversionSequence::Better; 2685 else if (isBetterReferenceBindingKind(SCS2, SCS1)) 2686 return ImplicitConversionSequence::Worse; 2687 2688 // C++ [over.ics.rank]p3b4: 2689 // -- S1 and S2 are reference bindings (8.5.3), and the types to 2690 // which the references refer are the same type except for 2691 // top-level cv-qualifiers, and the type to which the reference 2692 // initialized by S2 refers is more cv-qualified than the type 2693 // to which the reference initialized by S1 refers. 2694 QualType T1 = SCS1.getToType(2); 2695 QualType T2 = SCS2.getToType(2); 2696 T1 = S.Context.getCanonicalType(T1); 2697 T2 = S.Context.getCanonicalType(T2); 2698 Qualifiers T1Quals, T2Quals; 2699 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 2700 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 2701 if (UnqualT1 == UnqualT2) { 2702 // If the type is an array type, promote the element qualifiers to the 2703 // type for comparison. 2704 if (isa<ArrayType>(T1) && T1Quals) 2705 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 2706 if (isa<ArrayType>(T2) && T2Quals) 2707 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 2708 if (T2.isMoreQualifiedThan(T1)) 2709 return ImplicitConversionSequence::Better; 2710 else if (T1.isMoreQualifiedThan(T2)) 2711 return ImplicitConversionSequence::Worse; 2712 } 2713 } 2714 2715 return ImplicitConversionSequence::Indistinguishable; 2716} 2717 2718/// CompareQualificationConversions - Compares two standard conversion 2719/// sequences to determine whether they can be ranked based on their 2720/// qualification conversions (C++ 13.3.3.2p3 bullet 3). 2721ImplicitConversionSequence::CompareKind 2722CompareQualificationConversions(Sema &S, 2723 const StandardConversionSequence& SCS1, 2724 const StandardConversionSequence& SCS2) { 2725 // C++ 13.3.3.2p3: 2726 // -- S1 and S2 differ only in their qualification conversion and 2727 // yield similar types T1 and T2 (C++ 4.4), respectively, and the 2728 // cv-qualification signature of type T1 is a proper subset of 2729 // the cv-qualification signature of type T2, and S1 is not the 2730 // deprecated string literal array-to-pointer conversion (4.2). 2731 if (SCS1.First != SCS2.First || SCS1.Second != SCS2.Second || 2732 SCS1.Third != SCS2.Third || SCS1.Third != ICK_Qualification) 2733 return ImplicitConversionSequence::Indistinguishable; 2734 2735 // FIXME: the example in the standard doesn't use a qualification 2736 // conversion (!) 2737 QualType T1 = SCS1.getToType(2); 2738 QualType T2 = SCS2.getToType(2); 2739 T1 = S.Context.getCanonicalType(T1); 2740 T2 = S.Context.getCanonicalType(T2); 2741 Qualifiers T1Quals, T2Quals; 2742 QualType UnqualT1 = S.Context.getUnqualifiedArrayType(T1, T1Quals); 2743 QualType UnqualT2 = S.Context.getUnqualifiedArrayType(T2, T2Quals); 2744 2745 // If the types are the same, we won't learn anything by unwrapped 2746 // them. 2747 if (UnqualT1 == UnqualT2) 2748 return ImplicitConversionSequence::Indistinguishable; 2749 2750 // If the type is an array type, promote the element qualifiers to the type 2751 // for comparison. 2752 if (isa<ArrayType>(T1) && T1Quals) 2753 T1 = S.Context.getQualifiedType(UnqualT1, T1Quals); 2754 if (isa<ArrayType>(T2) && T2Quals) 2755 T2 = S.Context.getQualifiedType(UnqualT2, T2Quals); 2756 2757 ImplicitConversionSequence::CompareKind Result 2758 = ImplicitConversionSequence::Indistinguishable; 2759 while (S.Context.UnwrapSimilarPointerTypes(T1, T2)) { 2760 // Within each iteration of the loop, we check the qualifiers to 2761 // determine if this still looks like a qualification 2762 // conversion. Then, if all is well, we unwrap one more level of 2763 // pointers or pointers-to-members and do it all again 2764 // until there are no more pointers or pointers-to-members left 2765 // to unwrap. This essentially mimics what 2766 // IsQualificationConversion does, but here we're checking for a 2767 // strict subset of qualifiers. 2768 if (T1.getCVRQualifiers() == T2.getCVRQualifiers()) 2769 // The qualifiers are the same, so this doesn't tell us anything 2770 // about how the sequences rank. 2771 ; 2772 else if (T2.isMoreQualifiedThan(T1)) { 2773 // T1 has fewer qualifiers, so it could be the better sequence. 2774 if (Result == ImplicitConversionSequence::Worse) 2775 // Neither has qualifiers that are a subset of the other's 2776 // qualifiers. 2777 return ImplicitConversionSequence::Indistinguishable; 2778 2779 Result = ImplicitConversionSequence::Better; 2780 } else if (T1.isMoreQualifiedThan(T2)) { 2781 // T2 has fewer qualifiers, so it could be the better sequence. 2782 if (Result == ImplicitConversionSequence::Better) 2783 // Neither has qualifiers that are a subset of the other's 2784 // qualifiers. 2785 return ImplicitConversionSequence::Indistinguishable; 2786 2787 Result = ImplicitConversionSequence::Worse; 2788 } else { 2789 // Qualifiers are disjoint. 2790 return ImplicitConversionSequence::Indistinguishable; 2791 } 2792 2793 // If the types after this point are equivalent, we're done. 2794 if (S.Context.hasSameUnqualifiedType(T1, T2)) 2795 break; 2796 } 2797 2798 // Check that the winning standard conversion sequence isn't using 2799 // the deprecated string literal array to pointer conversion. 2800 switch (Result) { 2801 case ImplicitConversionSequence::Better: 2802 if (SCS1.DeprecatedStringLiteralToCharPtr) 2803 Result = ImplicitConversionSequence::Indistinguishable; 2804 break; 2805 2806 case ImplicitConversionSequence::Indistinguishable: 2807 break; 2808 2809 case ImplicitConversionSequence::Worse: 2810 if (SCS2.DeprecatedStringLiteralToCharPtr) 2811 Result = ImplicitConversionSequence::Indistinguishable; 2812 break; 2813 } 2814 2815 return Result; 2816} 2817 2818/// CompareDerivedToBaseConversions - Compares two standard conversion 2819/// sequences to determine whether they can be ranked based on their 2820/// various kinds of derived-to-base conversions (C++ 2821/// [over.ics.rank]p4b3). As part of these checks, we also look at 2822/// conversions between Objective-C interface types. 2823ImplicitConversionSequence::CompareKind 2824CompareDerivedToBaseConversions(Sema &S, 2825 const StandardConversionSequence& SCS1, 2826 const StandardConversionSequence& SCS2) { 2827 QualType FromType1 = SCS1.getFromType(); 2828 QualType ToType1 = SCS1.getToType(1); 2829 QualType FromType2 = SCS2.getFromType(); 2830 QualType ToType2 = SCS2.getToType(1); 2831 2832 // Adjust the types we're converting from via the array-to-pointer 2833 // conversion, if we need to. 2834 if (SCS1.First == ICK_Array_To_Pointer) 2835 FromType1 = S.Context.getArrayDecayedType(FromType1); 2836 if (SCS2.First == ICK_Array_To_Pointer) 2837 FromType2 = S.Context.getArrayDecayedType(FromType2); 2838 2839 // Canonicalize all of the types. 2840 FromType1 = S.Context.getCanonicalType(FromType1); 2841 ToType1 = S.Context.getCanonicalType(ToType1); 2842 FromType2 = S.Context.getCanonicalType(FromType2); 2843 ToType2 = S.Context.getCanonicalType(ToType2); 2844 2845 // C++ [over.ics.rank]p4b3: 2846 // 2847 // If class B is derived directly or indirectly from class A and 2848 // class C is derived directly or indirectly from B, 2849 // 2850 // Compare based on pointer conversions. 2851 if (SCS1.Second == ICK_Pointer_Conversion && 2852 SCS2.Second == ICK_Pointer_Conversion && 2853 /*FIXME: Remove if Objective-C id conversions get their own rank*/ 2854 FromType1->isPointerType() && FromType2->isPointerType() && 2855 ToType1->isPointerType() && ToType2->isPointerType()) { 2856 QualType FromPointee1 2857 = FromType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 2858 QualType ToPointee1 2859 = ToType1->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 2860 QualType FromPointee2 2861 = FromType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 2862 QualType ToPointee2 2863 = ToType2->getAs<PointerType>()->getPointeeType().getUnqualifiedType(); 2864 2865 // -- conversion of C* to B* is better than conversion of C* to A*, 2866 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 2867 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 2868 return ImplicitConversionSequence::Better; 2869 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 2870 return ImplicitConversionSequence::Worse; 2871 } 2872 2873 // -- conversion of B* to A* is better than conversion of C* to A*, 2874 if (FromPointee1 != FromPointee2 && ToPointee1 == ToPointee2) { 2875 if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 2876 return ImplicitConversionSequence::Better; 2877 else if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 2878 return ImplicitConversionSequence::Worse; 2879 } 2880 } else if (SCS1.Second == ICK_Pointer_Conversion && 2881 SCS2.Second == ICK_Pointer_Conversion) { 2882 const ObjCObjectPointerType *FromPtr1 2883 = FromType1->getAs<ObjCObjectPointerType>(); 2884 const ObjCObjectPointerType *FromPtr2 2885 = FromType2->getAs<ObjCObjectPointerType>(); 2886 const ObjCObjectPointerType *ToPtr1 2887 = ToType1->getAs<ObjCObjectPointerType>(); 2888 const ObjCObjectPointerType *ToPtr2 2889 = ToType2->getAs<ObjCObjectPointerType>(); 2890 2891 if (FromPtr1 && FromPtr2 && ToPtr1 && ToPtr2) { 2892 // Apply the same conversion ranking rules for Objective-C pointer types 2893 // that we do for C++ pointers to class types. However, we employ the 2894 // Objective-C pseudo-subtyping relationship used for assignment of 2895 // Objective-C pointer types. 2896 bool FromAssignLeft 2897 = S.Context.canAssignObjCInterfaces(FromPtr1, FromPtr2); 2898 bool FromAssignRight 2899 = S.Context.canAssignObjCInterfaces(FromPtr2, FromPtr1); 2900 bool ToAssignLeft 2901 = S.Context.canAssignObjCInterfaces(ToPtr1, ToPtr2); 2902 bool ToAssignRight 2903 = S.Context.canAssignObjCInterfaces(ToPtr2, ToPtr1); 2904 2905 // A conversion to an a non-id object pointer type or qualified 'id' 2906 // type is better than a conversion to 'id'. 2907 if (ToPtr1->isObjCIdType() && 2908 (ToPtr2->isObjCQualifiedIdType() || ToPtr2->getInterfaceDecl())) 2909 return ImplicitConversionSequence::Worse; 2910 if (ToPtr2->isObjCIdType() && 2911 (ToPtr1->isObjCQualifiedIdType() || ToPtr1->getInterfaceDecl())) 2912 return ImplicitConversionSequence::Better; 2913 2914 // A conversion to a non-id object pointer type is better than a 2915 // conversion to a qualified 'id' type 2916 if (ToPtr1->isObjCQualifiedIdType() && ToPtr2->getInterfaceDecl()) 2917 return ImplicitConversionSequence::Worse; 2918 if (ToPtr2->isObjCQualifiedIdType() && ToPtr1->getInterfaceDecl()) 2919 return ImplicitConversionSequence::Better; 2920 2921 // A conversion to an a non-Class object pointer type or qualified 'Class' 2922 // type is better than a conversion to 'Class'. 2923 if (ToPtr1->isObjCClassType() && 2924 (ToPtr2->isObjCQualifiedClassType() || ToPtr2->getInterfaceDecl())) 2925 return ImplicitConversionSequence::Worse; 2926 if (ToPtr2->isObjCClassType() && 2927 (ToPtr1->isObjCQualifiedClassType() || ToPtr1->getInterfaceDecl())) 2928 return ImplicitConversionSequence::Better; 2929 2930 // A conversion to a non-Class object pointer type is better than a 2931 // conversion to a qualified 'Class' type. 2932 if (ToPtr1->isObjCQualifiedClassType() && ToPtr2->getInterfaceDecl()) 2933 return ImplicitConversionSequence::Worse; 2934 if (ToPtr2->isObjCQualifiedClassType() && ToPtr1->getInterfaceDecl()) 2935 return ImplicitConversionSequence::Better; 2936 2937 // -- "conversion of C* to B* is better than conversion of C* to A*," 2938 if (S.Context.hasSameType(FromType1, FromType2) && 2939 !FromPtr1->isObjCIdType() && !FromPtr1->isObjCClassType() && 2940 (ToAssignLeft != ToAssignRight)) 2941 return ToAssignLeft? ImplicitConversionSequence::Worse 2942 : ImplicitConversionSequence::Better; 2943 2944 // -- "conversion of B* to A* is better than conversion of C* to A*," 2945 if (S.Context.hasSameUnqualifiedType(ToType1, ToType2) && 2946 (FromAssignLeft != FromAssignRight)) 2947 return FromAssignLeft? ImplicitConversionSequence::Better 2948 : ImplicitConversionSequence::Worse; 2949 } 2950 } 2951 2952 // Ranking of member-pointer types. 2953 if (SCS1.Second == ICK_Pointer_Member && SCS2.Second == ICK_Pointer_Member && 2954 FromType1->isMemberPointerType() && FromType2->isMemberPointerType() && 2955 ToType1->isMemberPointerType() && ToType2->isMemberPointerType()) { 2956 const MemberPointerType * FromMemPointer1 = 2957 FromType1->getAs<MemberPointerType>(); 2958 const MemberPointerType * ToMemPointer1 = 2959 ToType1->getAs<MemberPointerType>(); 2960 const MemberPointerType * FromMemPointer2 = 2961 FromType2->getAs<MemberPointerType>(); 2962 const MemberPointerType * ToMemPointer2 = 2963 ToType2->getAs<MemberPointerType>(); 2964 const Type *FromPointeeType1 = FromMemPointer1->getClass(); 2965 const Type *ToPointeeType1 = ToMemPointer1->getClass(); 2966 const Type *FromPointeeType2 = FromMemPointer2->getClass(); 2967 const Type *ToPointeeType2 = ToMemPointer2->getClass(); 2968 QualType FromPointee1 = QualType(FromPointeeType1, 0).getUnqualifiedType(); 2969 QualType ToPointee1 = QualType(ToPointeeType1, 0).getUnqualifiedType(); 2970 QualType FromPointee2 = QualType(FromPointeeType2, 0).getUnqualifiedType(); 2971 QualType ToPointee2 = QualType(ToPointeeType2, 0).getUnqualifiedType(); 2972 // conversion of A::* to B::* is better than conversion of A::* to C::*, 2973 if (FromPointee1 == FromPointee2 && ToPointee1 != ToPointee2) { 2974 if (S.IsDerivedFrom(ToPointee1, ToPointee2)) 2975 return ImplicitConversionSequence::Worse; 2976 else if (S.IsDerivedFrom(ToPointee2, ToPointee1)) 2977 return ImplicitConversionSequence::Better; 2978 } 2979 // conversion of B::* to C::* is better than conversion of A::* to C::* 2980 if (ToPointee1 == ToPointee2 && FromPointee1 != FromPointee2) { 2981 if (S.IsDerivedFrom(FromPointee1, FromPointee2)) 2982 return ImplicitConversionSequence::Better; 2983 else if (S.IsDerivedFrom(FromPointee2, FromPointee1)) 2984 return ImplicitConversionSequence::Worse; 2985 } 2986 } 2987 2988 if (SCS1.Second == ICK_Derived_To_Base) { 2989 // -- conversion of C to B is better than conversion of C to A, 2990 // -- binding of an expression of type C to a reference of type 2991 // B& is better than binding an expression of type C to a 2992 // reference of type A&, 2993 if (S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 2994 !S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 2995 if (S.IsDerivedFrom(ToType1, ToType2)) 2996 return ImplicitConversionSequence::Better; 2997 else if (S.IsDerivedFrom(ToType2, ToType1)) 2998 return ImplicitConversionSequence::Worse; 2999 } 3000 3001 // -- conversion of B to A is better than conversion of C to A. 3002 // -- binding of an expression of type B to a reference of type 3003 // A& is better than binding an expression of type C to a 3004 // reference of type A&, 3005 if (!S.Context.hasSameUnqualifiedType(FromType1, FromType2) && 3006 S.Context.hasSameUnqualifiedType(ToType1, ToType2)) { 3007 if (S.IsDerivedFrom(FromType2, FromType1)) 3008 return ImplicitConversionSequence::Better; 3009 else if (S.IsDerivedFrom(FromType1, FromType2)) 3010 return ImplicitConversionSequence::Worse; 3011 } 3012 } 3013 3014 return ImplicitConversionSequence::Indistinguishable; 3015} 3016 3017/// CompareReferenceRelationship - Compare the two types T1 and T2 to 3018/// determine whether they are reference-related, 3019/// reference-compatible, reference-compatible with added 3020/// qualification, or incompatible, for use in C++ initialization by 3021/// reference (C++ [dcl.ref.init]p4). Neither type can be a reference 3022/// type, and the first type (T1) is the pointee type of the reference 3023/// type being initialized. 3024Sema::ReferenceCompareResult 3025Sema::CompareReferenceRelationship(SourceLocation Loc, 3026 QualType OrigT1, QualType OrigT2, 3027 bool &DerivedToBase, 3028 bool &ObjCConversion) { 3029 assert(!OrigT1->isReferenceType() && 3030 "T1 must be the pointee type of the reference type"); 3031 assert(!OrigT2->isReferenceType() && "T2 cannot be a reference type"); 3032 3033 QualType T1 = Context.getCanonicalType(OrigT1); 3034 QualType T2 = Context.getCanonicalType(OrigT2); 3035 Qualifiers T1Quals, T2Quals; 3036 QualType UnqualT1 = Context.getUnqualifiedArrayType(T1, T1Quals); 3037 QualType UnqualT2 = Context.getUnqualifiedArrayType(T2, T2Quals); 3038 3039 // C++ [dcl.init.ref]p4: 3040 // Given types "cv1 T1" and "cv2 T2," "cv1 T1" is 3041 // reference-related to "cv2 T2" if T1 is the same type as T2, or 3042 // T1 is a base class of T2. 3043 DerivedToBase = false; 3044 ObjCConversion = false; 3045 if (UnqualT1 == UnqualT2) { 3046 // Nothing to do. 3047 } else if (!RequireCompleteType(Loc, OrigT2, PDiag()) && 3048 IsDerivedFrom(UnqualT2, UnqualT1)) 3049 DerivedToBase = true; 3050 else if (UnqualT1->isObjCObjectOrInterfaceType() && 3051 UnqualT2->isObjCObjectOrInterfaceType() && 3052 Context.canBindObjCObjectType(UnqualT1, UnqualT2)) 3053 ObjCConversion = true; 3054 else 3055 return Ref_Incompatible; 3056 3057 // At this point, we know that T1 and T2 are reference-related (at 3058 // least). 3059 3060 // If the type is an array type, promote the element qualifiers to the type 3061 // for comparison. 3062 if (isa<ArrayType>(T1) && T1Quals) 3063 T1 = Context.getQualifiedType(UnqualT1, T1Quals); 3064 if (isa<ArrayType>(T2) && T2Quals) 3065 T2 = Context.getQualifiedType(UnqualT2, T2Quals); 3066 3067 // C++ [dcl.init.ref]p4: 3068 // "cv1 T1" is reference-compatible with "cv2 T2" if T1 is 3069 // reference-related to T2 and cv1 is the same cv-qualification 3070 // as, or greater cv-qualification than, cv2. For purposes of 3071 // overload resolution, cases for which cv1 is greater 3072 // cv-qualification than cv2 are identified as 3073 // reference-compatible with added qualification (see 13.3.3.2). 3074 if (T1Quals.getCVRQualifiers() == T2Quals.getCVRQualifiers()) 3075 return Ref_Compatible; 3076 else if (T1.isMoreQualifiedThan(T2)) 3077 return Ref_Compatible_With_Added_Qualification; 3078 else 3079 return Ref_Related; 3080} 3081 3082/// \brief Look for a user-defined conversion to an value reference-compatible 3083/// with DeclType. Return true if something definite is found. 3084static bool 3085FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS, 3086 QualType DeclType, SourceLocation DeclLoc, 3087 Expr *Init, QualType T2, bool AllowRvalues, 3088 bool AllowExplicit) { 3089 assert(T2->isRecordType() && "Can only find conversions of record types."); 3090 CXXRecordDecl *T2RecordDecl 3091 = dyn_cast<CXXRecordDecl>(T2->getAs<RecordType>()->getDecl()); 3092 3093 OverloadCandidateSet CandidateSet(DeclLoc); 3094 const UnresolvedSetImpl *Conversions 3095 = T2RecordDecl->getVisibleConversionFunctions(); 3096 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 3097 E = Conversions->end(); I != E; ++I) { 3098 NamedDecl *D = *I; 3099 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 3100 if (isa<UsingShadowDecl>(D)) 3101 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 3102 3103 FunctionTemplateDecl *ConvTemplate 3104 = dyn_cast<FunctionTemplateDecl>(D); 3105 CXXConversionDecl *Conv; 3106 if (ConvTemplate) 3107 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 3108 else 3109 Conv = cast<CXXConversionDecl>(D); 3110 3111 // If this is an explicit conversion, and we're not allowed to consider 3112 // explicit conversions, skip it. 3113 if (!AllowExplicit && Conv->isExplicit()) 3114 continue; 3115 3116 if (AllowRvalues) { 3117 bool DerivedToBase = false; 3118 bool ObjCConversion = false; 3119 if (!ConvTemplate && 3120 S.CompareReferenceRelationship( 3121 DeclLoc, 3122 Conv->getConversionType().getNonReferenceType() 3123 .getUnqualifiedType(), 3124 DeclType.getNonReferenceType().getUnqualifiedType(), 3125 DerivedToBase, ObjCConversion) == 3126 Sema::Ref_Incompatible) 3127 continue; 3128 } else { 3129 // If the conversion function doesn't return a reference type, 3130 // it can't be considered for this conversion. An rvalue reference 3131 // is only acceptable if its referencee is a function type. 3132 3133 const ReferenceType *RefType = 3134 Conv->getConversionType()->getAs<ReferenceType>(); 3135 if (!RefType || 3136 (!RefType->isLValueReferenceType() && 3137 !RefType->getPointeeType()->isFunctionType())) 3138 continue; 3139 } 3140 3141 if (ConvTemplate) 3142 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), ActingDC, 3143 Init, DeclType, CandidateSet); 3144 else 3145 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Init, 3146 DeclType, CandidateSet); 3147 } 3148 3149 OverloadCandidateSet::iterator Best; 3150 switch (CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) { 3151 case OR_Success: 3152 // C++ [over.ics.ref]p1: 3153 // 3154 // [...] If the parameter binds directly to the result of 3155 // applying a conversion function to the argument 3156 // expression, the implicit conversion sequence is a 3157 // user-defined conversion sequence (13.3.3.1.2), with the 3158 // second standard conversion sequence either an identity 3159 // conversion or, if the conversion function returns an 3160 // entity of a type that is a derived class of the parameter 3161 // type, a derived-to-base Conversion. 3162 if (!Best->FinalConversion.DirectBinding) 3163 return false; 3164 3165 if (Best->Function) 3166 S.MarkDeclarationReferenced(DeclLoc, Best->Function); 3167 ICS.setUserDefined(); 3168 ICS.UserDefined.Before = Best->Conversions[0].Standard; 3169 ICS.UserDefined.After = Best->FinalConversion; 3170 ICS.UserDefined.ConversionFunction = Best->Function; 3171 ICS.UserDefined.FoundConversionFunction = Best->FoundDecl.getDecl(); 3172 ICS.UserDefined.EllipsisConversion = false; 3173 assert(ICS.UserDefined.After.ReferenceBinding && 3174 ICS.UserDefined.After.DirectBinding && 3175 "Expected a direct reference binding!"); 3176 return true; 3177 3178 case OR_Ambiguous: 3179 ICS.setAmbiguous(); 3180 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(); 3181 Cand != CandidateSet.end(); ++Cand) 3182 if (Cand->Viable) 3183 ICS.Ambiguous.addConversion(Cand->Function); 3184 return true; 3185 3186 case OR_No_Viable_Function: 3187 case OR_Deleted: 3188 // There was no suitable conversion, or we found a deleted 3189 // conversion; continue with other checks. 3190 return false; 3191 } 3192 3193 return false; 3194} 3195 3196/// \brief Compute an implicit conversion sequence for reference 3197/// initialization. 3198static ImplicitConversionSequence 3199TryReferenceInit(Sema &S, Expr *&Init, QualType DeclType, 3200 SourceLocation DeclLoc, 3201 bool SuppressUserConversions, 3202 bool AllowExplicit) { 3203 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 3204 3205 // Most paths end in a failed conversion. 3206 ImplicitConversionSequence ICS; 3207 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3208 3209 QualType T1 = DeclType->getAs<ReferenceType>()->getPointeeType(); 3210 QualType T2 = Init->getType(); 3211 3212 // If the initializer is the address of an overloaded function, try 3213 // to resolve the overloaded function. If all goes well, T2 is the 3214 // type of the resulting function. 3215 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) { 3216 DeclAccessPair Found; 3217 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Init, DeclType, 3218 false, Found)) 3219 T2 = Fn->getType(); 3220 } 3221 3222 // Compute some basic properties of the types and the initializer. 3223 bool isRValRef = DeclType->isRValueReferenceType(); 3224 bool DerivedToBase = false; 3225 bool ObjCConversion = false; 3226 Expr::Classification InitCategory = Init->Classify(S.Context); 3227 Sema::ReferenceCompareResult RefRelationship 3228 = S.CompareReferenceRelationship(DeclLoc, T1, T2, DerivedToBase, 3229 ObjCConversion); 3230 3231 3232 // C++0x [dcl.init.ref]p5: 3233 // A reference to type "cv1 T1" is initialized by an expression 3234 // of type "cv2 T2" as follows: 3235 3236 // -- If reference is an lvalue reference and the initializer expression 3237 if (!isRValRef) { 3238 // -- is an lvalue (but is not a bit-field), and "cv1 T1" is 3239 // reference-compatible with "cv2 T2," or 3240 // 3241 // Per C++ [over.ics.ref]p4, we don't check the bit-field property here. 3242 if (InitCategory.isLValue() && 3243 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 3244 // C++ [over.ics.ref]p1: 3245 // When a parameter of reference type binds directly (8.5.3) 3246 // to an argument expression, the implicit conversion sequence 3247 // is the identity conversion, unless the argument expression 3248 // has a type that is a derived class of the parameter type, 3249 // in which case the implicit conversion sequence is a 3250 // derived-to-base Conversion (13.3.3.1). 3251 ICS.setStandard(); 3252 ICS.Standard.First = ICK_Identity; 3253 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3254 : ObjCConversion? ICK_Compatible_Conversion 3255 : ICK_Identity; 3256 ICS.Standard.Third = ICK_Identity; 3257 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3258 ICS.Standard.setToType(0, T2); 3259 ICS.Standard.setToType(1, T1); 3260 ICS.Standard.setToType(2, T1); 3261 ICS.Standard.ReferenceBinding = true; 3262 ICS.Standard.DirectBinding = true; 3263 ICS.Standard.IsLvalueReference = !isRValRef; 3264 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3265 ICS.Standard.BindsToRvalue = false; 3266 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3267 ICS.Standard.CopyConstructor = 0; 3268 3269 // Nothing more to do: the inaccessibility/ambiguity check for 3270 // derived-to-base conversions is suppressed when we're 3271 // computing the implicit conversion sequence (C++ 3272 // [over.best.ics]p2). 3273 return ICS; 3274 } 3275 3276 // -- has a class type (i.e., T2 is a class type), where T1 is 3277 // not reference-related to T2, and can be implicitly 3278 // converted to an lvalue of type "cv3 T3," where "cv1 T1" 3279 // is reference-compatible with "cv3 T3" 92) (this 3280 // conversion is selected by enumerating the applicable 3281 // conversion functions (13.3.1.6) and choosing the best 3282 // one through overload resolution (13.3)), 3283 if (!SuppressUserConversions && T2->isRecordType() && 3284 !S.RequireCompleteType(DeclLoc, T2, 0) && 3285 RefRelationship == Sema::Ref_Incompatible) { 3286 if (FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3287 Init, T2, /*AllowRvalues=*/false, 3288 AllowExplicit)) 3289 return ICS; 3290 } 3291 } 3292 3293 // -- Otherwise, the reference shall be an lvalue reference to a 3294 // non-volatile const type (i.e., cv1 shall be const), or the reference 3295 // shall be an rvalue reference. 3296 // 3297 // We actually handle one oddity of C++ [over.ics.ref] at this 3298 // point, which is that, due to p2 (which short-circuits reference 3299 // binding by only attempting a simple conversion for non-direct 3300 // bindings) and p3's strange wording, we allow a const volatile 3301 // reference to bind to an rvalue. Hence the check for the presence 3302 // of "const" rather than checking for "const" being the only 3303 // qualifier. 3304 // This is also the point where rvalue references and lvalue inits no longer 3305 // go together. 3306 if (!isRValRef && !T1.isConstQualified()) 3307 return ICS; 3308 3309 // -- If the initializer expression 3310 // 3311 // -- is an xvalue, class prvalue, array prvalue or function 3312 // lvalue and "cv1T1" is reference-compatible with "cv2 T2", or 3313 if (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification && 3314 (InitCategory.isXValue() || 3315 (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) || 3316 (InitCategory.isLValue() && T2->isFunctionType()))) { 3317 ICS.setStandard(); 3318 ICS.Standard.First = ICK_Identity; 3319 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3320 : ObjCConversion? ICK_Compatible_Conversion 3321 : ICK_Identity; 3322 ICS.Standard.Third = ICK_Identity; 3323 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3324 ICS.Standard.setToType(0, T2); 3325 ICS.Standard.setToType(1, T1); 3326 ICS.Standard.setToType(2, T1); 3327 ICS.Standard.ReferenceBinding = true; 3328 // In C++0x, this is always a direct binding. In C++98/03, it's a direct 3329 // binding unless we're binding to a class prvalue. 3330 // Note: Although xvalues wouldn't normally show up in C++98/03 code, we 3331 // allow the use of rvalue references in C++98/03 for the benefit of 3332 // standard library implementors; therefore, we need the xvalue check here. 3333 ICS.Standard.DirectBinding = 3334 S.getLangOptions().CPlusPlus0x || 3335 (InitCategory.isPRValue() && !T2->isRecordType()); 3336 ICS.Standard.IsLvalueReference = !isRValRef; 3337 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3338 ICS.Standard.BindsToRvalue = InitCategory.isRValue(); 3339 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3340 ICS.Standard.CopyConstructor = 0; 3341 return ICS; 3342 } 3343 3344 // -- has a class type (i.e., T2 is a class type), where T1 is not 3345 // reference-related to T2, and can be implicitly converted to 3346 // an xvalue, class prvalue, or function lvalue of type 3347 // "cv3 T3", where "cv1 T1" is reference-compatible with 3348 // "cv3 T3", 3349 // 3350 // then the reference is bound to the value of the initializer 3351 // expression in the first case and to the result of the conversion 3352 // in the second case (or, in either case, to an appropriate base 3353 // class subobject). 3354 if (!SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3355 T2->isRecordType() && !S.RequireCompleteType(DeclLoc, T2, 0) && 3356 FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3357 Init, T2, /*AllowRvalues=*/true, 3358 AllowExplicit)) { 3359 // In the second case, if the reference is an rvalue reference 3360 // and the second standard conversion sequence of the 3361 // user-defined conversion sequence includes an lvalue-to-rvalue 3362 // conversion, the program is ill-formed. 3363 if (ICS.isUserDefined() && isRValRef && 3364 ICS.UserDefined.After.First == ICK_Lvalue_To_Rvalue) 3365 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3366 3367 return ICS; 3368 } 3369 3370 // -- Otherwise, a temporary of type "cv1 T1" is created and 3371 // initialized from the initializer expression using the 3372 // rules for a non-reference copy initialization (8.5). The 3373 // reference is then bound to the temporary. If T1 is 3374 // reference-related to T2, cv1 must be the same 3375 // cv-qualification as, or greater cv-qualification than, 3376 // cv2; otherwise, the program is ill-formed. 3377 if (RefRelationship == Sema::Ref_Related) { 3378 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 3379 // we would be reference-compatible or reference-compatible with 3380 // added qualification. But that wasn't the case, so the reference 3381 // initialization fails. 3382 return ICS; 3383 } 3384 3385 // If at least one of the types is a class type, the types are not 3386 // related, and we aren't allowed any user conversions, the 3387 // reference binding fails. This case is important for breaking 3388 // recursion, since TryImplicitConversion below will attempt to 3389 // create a temporary through the use of a copy constructor. 3390 if (SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3391 (T1->isRecordType() || T2->isRecordType())) 3392 return ICS; 3393 3394 // If T1 is reference-related to T2 and the reference is an rvalue 3395 // reference, the initializer expression shall not be an lvalue. 3396 if (RefRelationship >= Sema::Ref_Related && 3397 isRValRef && Init->Classify(S.Context).isLValue()) 3398 return ICS; 3399 3400 // C++ [over.ics.ref]p2: 3401 // When a parameter of reference type is not bound directly to 3402 // an argument expression, the conversion sequence is the one 3403 // required to convert the argument expression to the 3404 // underlying type of the reference according to 3405 // 13.3.3.1. Conceptually, this conversion sequence corresponds 3406 // to copy-initializing a temporary of the underlying type with 3407 // the argument expression. Any difference in top-level 3408 // cv-qualification is subsumed by the initialization itself 3409 // and does not constitute a conversion. 3410 ICS = TryImplicitConversion(S, Init, T1, SuppressUserConversions, 3411 /*AllowExplicit=*/false, 3412 /*InOverloadResolution=*/false, 3413 /*CStyle=*/false); 3414 3415 // Of course, that's still a reference binding. 3416 if (ICS.isStandard()) { 3417 ICS.Standard.ReferenceBinding = true; 3418 ICS.Standard.IsLvalueReference = !isRValRef; 3419 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3420 ICS.Standard.BindsToRvalue = true; 3421 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3422 } else if (ICS.isUserDefined()) { 3423 ICS.UserDefined.After.ReferenceBinding = true; 3424 ICS.Standard.IsLvalueReference = !isRValRef; 3425 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3426 ICS.Standard.BindsToRvalue = true; 3427 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3428 } 3429 3430 return ICS; 3431} 3432 3433/// TryCopyInitialization - Try to copy-initialize a value of type 3434/// ToType from the expression From. Return the implicit conversion 3435/// sequence required to pass this argument, which may be a bad 3436/// conversion sequence (meaning that the argument cannot be passed to 3437/// a parameter of this type). If @p SuppressUserConversions, then we 3438/// do not permit any user-defined conversion sequences. 3439static ImplicitConversionSequence 3440TryCopyInitialization(Sema &S, Expr *From, QualType ToType, 3441 bool SuppressUserConversions, 3442 bool InOverloadResolution) { 3443 if (ToType->isReferenceType()) 3444 return TryReferenceInit(S, From, ToType, 3445 /*FIXME:*/From->getLocStart(), 3446 SuppressUserConversions, 3447 /*AllowExplicit=*/false); 3448 3449 return TryImplicitConversion(S, From, ToType, 3450 SuppressUserConversions, 3451 /*AllowExplicit=*/false, 3452 InOverloadResolution, 3453 /*CStyle=*/false); 3454} 3455 3456/// TryObjectArgumentInitialization - Try to initialize the object 3457/// parameter of the given member function (@c Method) from the 3458/// expression @p From. 3459static ImplicitConversionSequence 3460TryObjectArgumentInitialization(Sema &S, QualType OrigFromType, 3461 Expr::Classification FromClassification, 3462 CXXMethodDecl *Method, 3463 CXXRecordDecl *ActingContext) { 3464 QualType ClassType = S.Context.getTypeDeclType(ActingContext); 3465 // [class.dtor]p2: A destructor can be invoked for a const, volatile or 3466 // const volatile object. 3467 unsigned Quals = isa<CXXDestructorDecl>(Method) ? 3468 Qualifiers::Const | Qualifiers::Volatile : Method->getTypeQualifiers(); 3469 QualType ImplicitParamType = S.Context.getCVRQualifiedType(ClassType, Quals); 3470 3471 // Set up the conversion sequence as a "bad" conversion, to allow us 3472 // to exit early. 3473 ImplicitConversionSequence ICS; 3474 3475 // We need to have an object of class type. 3476 QualType FromType = OrigFromType; 3477 if (const PointerType *PT = FromType->getAs<PointerType>()) { 3478 FromType = PT->getPointeeType(); 3479 3480 // When we had a pointer, it's implicitly dereferenced, so we 3481 // better have an lvalue. 3482 assert(FromClassification.isLValue()); 3483 } 3484 3485 assert(FromType->isRecordType()); 3486 3487 // C++0x [over.match.funcs]p4: 3488 // For non-static member functions, the type of the implicit object 3489 // parameter is 3490 // 3491 // - "lvalue reference to cv X" for functions declared without a 3492 // ref-qualifier or with the & ref-qualifier 3493 // - "rvalue reference to cv X" for functions declared with the && 3494 // ref-qualifier 3495 // 3496 // where X is the class of which the function is a member and cv is the 3497 // cv-qualification on the member function declaration. 3498 // 3499 // However, when finding an implicit conversion sequence for the argument, we 3500 // are not allowed to create temporaries or perform user-defined conversions 3501 // (C++ [over.match.funcs]p5). We perform a simplified version of 3502 // reference binding here, that allows class rvalues to bind to 3503 // non-constant references. 3504 3505 // First check the qualifiers. 3506 QualType FromTypeCanon = S.Context.getCanonicalType(FromType); 3507 if (ImplicitParamType.getCVRQualifiers() 3508 != FromTypeCanon.getLocalCVRQualifiers() && 3509 !ImplicitParamType.isAtLeastAsQualifiedAs(FromTypeCanon)) { 3510 ICS.setBad(BadConversionSequence::bad_qualifiers, 3511 OrigFromType, ImplicitParamType); 3512 return ICS; 3513 } 3514 3515 // Check that we have either the same type or a derived type. It 3516 // affects the conversion rank. 3517 QualType ClassTypeCanon = S.Context.getCanonicalType(ClassType); 3518 ImplicitConversionKind SecondKind; 3519 if (ClassTypeCanon == FromTypeCanon.getLocalUnqualifiedType()) { 3520 SecondKind = ICK_Identity; 3521 } else if (S.IsDerivedFrom(FromType, ClassType)) 3522 SecondKind = ICK_Derived_To_Base; 3523 else { 3524 ICS.setBad(BadConversionSequence::unrelated_class, 3525 FromType, ImplicitParamType); 3526 return ICS; 3527 } 3528 3529 // Check the ref-qualifier. 3530 switch (Method->getRefQualifier()) { 3531 case RQ_None: 3532 // Do nothing; we don't care about lvalueness or rvalueness. 3533 break; 3534 3535 case RQ_LValue: 3536 if (!FromClassification.isLValue() && Quals != Qualifiers::Const) { 3537 // non-const lvalue reference cannot bind to an rvalue 3538 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, FromType, 3539 ImplicitParamType); 3540 return ICS; 3541 } 3542 break; 3543 3544 case RQ_RValue: 3545 if (!FromClassification.isRValue()) { 3546 // rvalue reference cannot bind to an lvalue 3547 ICS.setBad(BadConversionSequence::rvalue_ref_to_lvalue, FromType, 3548 ImplicitParamType); 3549 return ICS; 3550 } 3551 break; 3552 } 3553 3554 // Success. Mark this as a reference binding. 3555 ICS.setStandard(); 3556 ICS.Standard.setAsIdentityConversion(); 3557 ICS.Standard.Second = SecondKind; 3558 ICS.Standard.setFromType(FromType); 3559 ICS.Standard.setAllToTypes(ImplicitParamType); 3560 ICS.Standard.ReferenceBinding = true; 3561 ICS.Standard.DirectBinding = true; 3562 ICS.Standard.IsLvalueReference = Method->getRefQualifier() != RQ_RValue; 3563 ICS.Standard.BindsToFunctionLvalue = false; 3564 ICS.Standard.BindsToRvalue = FromClassification.isRValue(); 3565 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier 3566 = (Method->getRefQualifier() == RQ_None); 3567 return ICS; 3568} 3569 3570/// PerformObjectArgumentInitialization - Perform initialization of 3571/// the implicit object parameter for the given Method with the given 3572/// expression. 3573ExprResult 3574Sema::PerformObjectArgumentInitialization(Expr *From, 3575 NestedNameSpecifier *Qualifier, 3576 NamedDecl *FoundDecl, 3577 CXXMethodDecl *Method) { 3578 QualType FromRecordType, DestType; 3579 QualType ImplicitParamRecordType = 3580 Method->getThisType(Context)->getAs<PointerType>()->getPointeeType(); 3581 3582 Expr::Classification FromClassification; 3583 if (const PointerType *PT = From->getType()->getAs<PointerType>()) { 3584 FromRecordType = PT->getPointeeType(); 3585 DestType = Method->getThisType(Context); 3586 FromClassification = Expr::Classification::makeSimpleLValue(); 3587 } else { 3588 FromRecordType = From->getType(); 3589 DestType = ImplicitParamRecordType; 3590 FromClassification = From->Classify(Context); 3591 } 3592 3593 // Note that we always use the true parent context when performing 3594 // the actual argument initialization. 3595 ImplicitConversionSequence ICS 3596 = TryObjectArgumentInitialization(*this, From->getType(), FromClassification, 3597 Method, Method->getParent()); 3598 if (ICS.isBad()) { 3599 if (ICS.Bad.Kind == BadConversionSequence::bad_qualifiers) { 3600 Qualifiers FromQs = FromRecordType.getQualifiers(); 3601 Qualifiers ToQs = DestType.getQualifiers(); 3602 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 3603 if (CVR) { 3604 Diag(From->getSourceRange().getBegin(), 3605 diag::err_member_function_call_bad_cvr) 3606 << Method->getDeclName() << FromRecordType << (CVR - 1) 3607 << From->getSourceRange(); 3608 Diag(Method->getLocation(), diag::note_previous_decl) 3609 << Method->getDeclName(); 3610 return ExprError(); 3611 } 3612 } 3613 3614 return Diag(From->getSourceRange().getBegin(), 3615 diag::err_implicit_object_parameter_init) 3616 << ImplicitParamRecordType << FromRecordType << From->getSourceRange(); 3617 } 3618 3619 if (ICS.Standard.Second == ICK_Derived_To_Base) { 3620 ExprResult FromRes = 3621 PerformObjectMemberConversion(From, Qualifier, FoundDecl, Method); 3622 if (FromRes.isInvalid()) 3623 return ExprError(); 3624 From = FromRes.take(); 3625 } 3626 3627 if (!Context.hasSameType(From->getType(), DestType)) 3628 From = ImpCastExprToType(From, DestType, CK_NoOp, 3629 From->getType()->isPointerType() ? VK_RValue : VK_LValue).take(); 3630 return Owned(From); 3631} 3632 3633/// TryContextuallyConvertToBool - Attempt to contextually convert the 3634/// expression From to bool (C++0x [conv]p3). 3635static ImplicitConversionSequence 3636TryContextuallyConvertToBool(Sema &S, Expr *From) { 3637 // FIXME: This is pretty broken. 3638 return TryImplicitConversion(S, From, S.Context.BoolTy, 3639 // FIXME: Are these flags correct? 3640 /*SuppressUserConversions=*/false, 3641 /*AllowExplicit=*/true, 3642 /*InOverloadResolution=*/false, 3643 /*CStyle=*/false); 3644} 3645 3646/// PerformContextuallyConvertToBool - Perform a contextual conversion 3647/// of the expression From to bool (C++0x [conv]p3). 3648ExprResult Sema::PerformContextuallyConvertToBool(Expr *From) { 3649 ImplicitConversionSequence ICS = TryContextuallyConvertToBool(*this, From); 3650 if (!ICS.isBad()) 3651 return PerformImplicitConversion(From, Context.BoolTy, ICS, AA_Converting); 3652 3653 if (!DiagnoseMultipleUserDefinedConversion(From, Context.BoolTy)) 3654 return Diag(From->getSourceRange().getBegin(), 3655 diag::err_typecheck_bool_condition) 3656 << From->getType() << From->getSourceRange(); 3657 return ExprError(); 3658} 3659 3660/// TryContextuallyConvertToObjCId - Attempt to contextually convert the 3661/// expression From to 'id'. 3662static ImplicitConversionSequence 3663TryContextuallyConvertToObjCId(Sema &S, Expr *From) { 3664 QualType Ty = S.Context.getObjCIdType(); 3665 return TryImplicitConversion(S, From, Ty, 3666 // FIXME: Are these flags correct? 3667 /*SuppressUserConversions=*/false, 3668 /*AllowExplicit=*/true, 3669 /*InOverloadResolution=*/false, 3670 /*CStyle=*/false); 3671} 3672 3673/// PerformContextuallyConvertToObjCId - Perform a contextual conversion 3674/// of the expression From to 'id'. 3675ExprResult Sema::PerformContextuallyConvertToObjCId(Expr *From) { 3676 QualType Ty = Context.getObjCIdType(); 3677 ImplicitConversionSequence ICS = TryContextuallyConvertToObjCId(*this, From); 3678 if (!ICS.isBad()) 3679 return PerformImplicitConversion(From, Ty, ICS, AA_Converting); 3680 return ExprError(); 3681} 3682 3683/// \brief Attempt to convert the given expression to an integral or 3684/// enumeration type. 3685/// 3686/// This routine will attempt to convert an expression of class type to an 3687/// integral or enumeration type, if that class type only has a single 3688/// conversion to an integral or enumeration type. 3689/// 3690/// \param Loc The source location of the construct that requires the 3691/// conversion. 3692/// 3693/// \param FromE The expression we're converting from. 3694/// 3695/// \param NotIntDiag The diagnostic to be emitted if the expression does not 3696/// have integral or enumeration type. 3697/// 3698/// \param IncompleteDiag The diagnostic to be emitted if the expression has 3699/// incomplete class type. 3700/// 3701/// \param ExplicitConvDiag The diagnostic to be emitted if we're calling an 3702/// explicit conversion function (because no implicit conversion functions 3703/// were available). This is a recovery mode. 3704/// 3705/// \param ExplicitConvNote The note to be emitted with \p ExplicitConvDiag, 3706/// showing which conversion was picked. 3707/// 3708/// \param AmbigDiag The diagnostic to be emitted if there is more than one 3709/// conversion function that could convert to integral or enumeration type. 3710/// 3711/// \param AmbigNote The note to be emitted with \p AmbigDiag for each 3712/// usable conversion function. 3713/// 3714/// \param ConvDiag The diagnostic to be emitted if we are calling a conversion 3715/// function, which may be an extension in this case. 3716/// 3717/// \returns The expression, converted to an integral or enumeration type if 3718/// successful. 3719ExprResult 3720Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From, 3721 const PartialDiagnostic &NotIntDiag, 3722 const PartialDiagnostic &IncompleteDiag, 3723 const PartialDiagnostic &ExplicitConvDiag, 3724 const PartialDiagnostic &ExplicitConvNote, 3725 const PartialDiagnostic &AmbigDiag, 3726 const PartialDiagnostic &AmbigNote, 3727 const PartialDiagnostic &ConvDiag) { 3728 // We can't perform any more checking for type-dependent expressions. 3729 if (From->isTypeDependent()) 3730 return Owned(From); 3731 3732 // If the expression already has integral or enumeration type, we're golden. 3733 QualType T = From->getType(); 3734 if (T->isIntegralOrEnumerationType()) 3735 return Owned(From); 3736 3737 // FIXME: Check for missing '()' if T is a function type? 3738 3739 // If we don't have a class type in C++, there's no way we can get an 3740 // expression of integral or enumeration type. 3741 const RecordType *RecordTy = T->getAs<RecordType>(); 3742 if (!RecordTy || !getLangOptions().CPlusPlus) { 3743 Diag(Loc, NotIntDiag) 3744 << T << From->getSourceRange(); 3745 return Owned(From); 3746 } 3747 3748 // We must have a complete class type. 3749 if (RequireCompleteType(Loc, T, IncompleteDiag)) 3750 return Owned(From); 3751 3752 // Look for a conversion to an integral or enumeration type. 3753 UnresolvedSet<4> ViableConversions; 3754 UnresolvedSet<4> ExplicitConversions; 3755 const UnresolvedSetImpl *Conversions 3756 = cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions(); 3757 3758 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 3759 E = Conversions->end(); 3760 I != E; 3761 ++I) { 3762 if (CXXConversionDecl *Conversion 3763 = dyn_cast<CXXConversionDecl>((*I)->getUnderlyingDecl())) 3764 if (Conversion->getConversionType().getNonReferenceType() 3765 ->isIntegralOrEnumerationType()) { 3766 if (Conversion->isExplicit()) 3767 ExplicitConversions.addDecl(I.getDecl(), I.getAccess()); 3768 else 3769 ViableConversions.addDecl(I.getDecl(), I.getAccess()); 3770 } 3771 } 3772 3773 switch (ViableConversions.size()) { 3774 case 0: 3775 if (ExplicitConversions.size() == 1) { 3776 DeclAccessPair Found = ExplicitConversions[0]; 3777 CXXConversionDecl *Conversion 3778 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 3779 3780 // The user probably meant to invoke the given explicit 3781 // conversion; use it. 3782 QualType ConvTy 3783 = Conversion->getConversionType().getNonReferenceType(); 3784 std::string TypeStr; 3785 ConvTy.getAsStringInternal(TypeStr, Context.PrintingPolicy); 3786 3787 Diag(Loc, ExplicitConvDiag) 3788 << T << ConvTy 3789 << FixItHint::CreateInsertion(From->getLocStart(), 3790 "static_cast<" + TypeStr + ">(") 3791 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(From->getLocEnd()), 3792 ")"); 3793 Diag(Conversion->getLocation(), ExplicitConvNote) 3794 << ConvTy->isEnumeralType() << ConvTy; 3795 3796 // If we aren't in a SFINAE context, build a call to the 3797 // explicit conversion function. 3798 if (isSFINAEContext()) 3799 return ExprError(); 3800 3801 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 3802 ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion); 3803 if (Result.isInvalid()) 3804 return ExprError(); 3805 3806 From = Result.get(); 3807 } 3808 3809 // We'll complain below about a non-integral condition type. 3810 break; 3811 3812 case 1: { 3813 // Apply this conversion. 3814 DeclAccessPair Found = ViableConversions[0]; 3815 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 3816 3817 CXXConversionDecl *Conversion 3818 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 3819 QualType ConvTy 3820 = Conversion->getConversionType().getNonReferenceType(); 3821 if (ConvDiag.getDiagID()) { 3822 if (isSFINAEContext()) 3823 return ExprError(); 3824 3825 Diag(Loc, ConvDiag) 3826 << T << ConvTy->isEnumeralType() << ConvTy << From->getSourceRange(); 3827 } 3828 3829 ExprResult Result = BuildCXXMemberCallExpr(From, Found, 3830 cast<CXXConversionDecl>(Found->getUnderlyingDecl())); 3831 if (Result.isInvalid()) 3832 return ExprError(); 3833 3834 From = Result.get(); 3835 break; 3836 } 3837 3838 default: 3839 Diag(Loc, AmbigDiag) 3840 << T << From->getSourceRange(); 3841 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) { 3842 CXXConversionDecl *Conv 3843 = cast<CXXConversionDecl>(ViableConversions[I]->getUnderlyingDecl()); 3844 QualType ConvTy = Conv->getConversionType().getNonReferenceType(); 3845 Diag(Conv->getLocation(), AmbigNote) 3846 << ConvTy->isEnumeralType() << ConvTy; 3847 } 3848 return Owned(From); 3849 } 3850 3851 if (!From->getType()->isIntegralOrEnumerationType()) 3852 Diag(Loc, NotIntDiag) 3853 << From->getType() << From->getSourceRange(); 3854 3855 return Owned(From); 3856} 3857 3858/// AddOverloadCandidate - Adds the given function to the set of 3859/// candidate functions, using the given function call arguments. If 3860/// @p SuppressUserConversions, then don't allow user-defined 3861/// conversions via constructors or conversion operators. 3862/// 3863/// \para PartialOverloading true if we are performing "partial" overloading 3864/// based on an incomplete set of function arguments. This feature is used by 3865/// code completion. 3866void 3867Sema::AddOverloadCandidate(FunctionDecl *Function, 3868 DeclAccessPair FoundDecl, 3869 Expr **Args, unsigned NumArgs, 3870 OverloadCandidateSet& CandidateSet, 3871 bool SuppressUserConversions, 3872 bool PartialOverloading) { 3873 const FunctionProtoType* Proto 3874 = dyn_cast<FunctionProtoType>(Function->getType()->getAs<FunctionType>()); 3875 assert(Proto && "Functions without a prototype cannot be overloaded"); 3876 assert(!Function->getDescribedFunctionTemplate() && 3877 "Use AddTemplateOverloadCandidate for function templates"); 3878 3879 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { 3880 if (!isa<CXXConstructorDecl>(Method)) { 3881 // If we get here, it's because we're calling a member function 3882 // that is named without a member access expression (e.g., 3883 // "this->f") that was either written explicitly or created 3884 // implicitly. This can happen with a qualified call to a member 3885 // function, e.g., X::f(). We use an empty type for the implied 3886 // object argument (C++ [over.call.func]p3), and the acting context 3887 // is irrelevant. 3888 AddMethodCandidate(Method, FoundDecl, Method->getParent(), 3889 QualType(), Expr::Classification::makeSimpleLValue(), 3890 Args, NumArgs, CandidateSet, 3891 SuppressUserConversions); 3892 return; 3893 } 3894 // We treat a constructor like a non-member function, since its object 3895 // argument doesn't participate in overload resolution. 3896 } 3897 3898 if (!CandidateSet.isNewCandidate(Function)) 3899 return; 3900 3901 // Overload resolution is always an unevaluated context. 3902 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 3903 3904 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Function)){ 3905 // C++ [class.copy]p3: 3906 // A member function template is never instantiated to perform the copy 3907 // of a class object to an object of its class type. 3908 QualType ClassType = Context.getTypeDeclType(Constructor->getParent()); 3909 if (NumArgs == 1 && 3910 Constructor->isSpecializationCopyingObject() && 3911 (Context.hasSameUnqualifiedType(ClassType, Args[0]->getType()) || 3912 IsDerivedFrom(Args[0]->getType(), ClassType))) 3913 return; 3914 } 3915 3916 // Add this candidate 3917 CandidateSet.push_back(OverloadCandidate()); 3918 OverloadCandidate& Candidate = CandidateSet.back(); 3919 Candidate.FoundDecl = FoundDecl; 3920 Candidate.Function = Function; 3921 Candidate.Viable = true; 3922 Candidate.IsSurrogate = false; 3923 Candidate.IgnoreObjectArgument = false; 3924 Candidate.ExplicitCallArguments = NumArgs; 3925 3926 unsigned NumArgsInProto = Proto->getNumArgs(); 3927 3928 // (C++ 13.3.2p2): A candidate function having fewer than m 3929 // parameters is viable only if it has an ellipsis in its parameter 3930 // list (8.3.5). 3931 if ((NumArgs + (PartialOverloading && NumArgs)) > NumArgsInProto && 3932 !Proto->isVariadic()) { 3933 Candidate.Viable = false; 3934 Candidate.FailureKind = ovl_fail_too_many_arguments; 3935 return; 3936 } 3937 3938 // (C++ 13.3.2p2): A candidate function having more than m parameters 3939 // is viable only if the (m+1)st parameter has a default argument 3940 // (8.3.6). For the purposes of overload resolution, the 3941 // parameter list is truncated on the right, so that there are 3942 // exactly m parameters. 3943 unsigned MinRequiredArgs = Function->getMinRequiredArguments(); 3944 if (NumArgs < MinRequiredArgs && !PartialOverloading) { 3945 // Not enough arguments. 3946 Candidate.Viable = false; 3947 Candidate.FailureKind = ovl_fail_too_few_arguments; 3948 return; 3949 } 3950 3951 // Determine the implicit conversion sequences for each of the 3952 // arguments. 3953 Candidate.Conversions.resize(NumArgs); 3954 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 3955 if (ArgIdx < NumArgsInProto) { 3956 // (C++ 13.3.2p3): for F to be a viable function, there shall 3957 // exist for each argument an implicit conversion sequence 3958 // (13.3.3.1) that converts that argument to the corresponding 3959 // parameter of F. 3960 QualType ParamType = Proto->getArgType(ArgIdx); 3961 Candidate.Conversions[ArgIdx] 3962 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 3963 SuppressUserConversions, 3964 /*InOverloadResolution=*/true); 3965 if (Candidate.Conversions[ArgIdx].isBad()) { 3966 Candidate.Viable = false; 3967 Candidate.FailureKind = ovl_fail_bad_conversion; 3968 break; 3969 } 3970 } else { 3971 // (C++ 13.3.2p2): For the purposes of overload resolution, any 3972 // argument for which there is no corresponding parameter is 3973 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 3974 Candidate.Conversions[ArgIdx].setEllipsis(); 3975 } 3976 } 3977} 3978 3979/// \brief Add all of the function declarations in the given function set to 3980/// the overload canddiate set. 3981void Sema::AddFunctionCandidates(const UnresolvedSetImpl &Fns, 3982 Expr **Args, unsigned NumArgs, 3983 OverloadCandidateSet& CandidateSet, 3984 bool SuppressUserConversions) { 3985 for (UnresolvedSetIterator F = Fns.begin(), E = Fns.end(); F != E; ++F) { 3986 NamedDecl *D = F.getDecl()->getUnderlyingDecl(); 3987 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 3988 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 3989 AddMethodCandidate(cast<CXXMethodDecl>(FD), F.getPair(), 3990 cast<CXXMethodDecl>(FD)->getParent(), 3991 Args[0]->getType(), Args[0]->Classify(Context), 3992 Args + 1, NumArgs - 1, 3993 CandidateSet, SuppressUserConversions); 3994 else 3995 AddOverloadCandidate(FD, F.getPair(), Args, NumArgs, CandidateSet, 3996 SuppressUserConversions); 3997 } else { 3998 FunctionTemplateDecl *FunTmpl = cast<FunctionTemplateDecl>(D); 3999 if (isa<CXXMethodDecl>(FunTmpl->getTemplatedDecl()) && 4000 !cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl())->isStatic()) 4001 AddMethodTemplateCandidate(FunTmpl, F.getPair(), 4002 cast<CXXRecordDecl>(FunTmpl->getDeclContext()), 4003 /*FIXME: explicit args */ 0, 4004 Args[0]->getType(), 4005 Args[0]->Classify(Context), 4006 Args + 1, NumArgs - 1, 4007 CandidateSet, 4008 SuppressUserConversions); 4009 else 4010 AddTemplateOverloadCandidate(FunTmpl, F.getPair(), 4011 /*FIXME: explicit args */ 0, 4012 Args, NumArgs, CandidateSet, 4013 SuppressUserConversions); 4014 } 4015 } 4016} 4017 4018/// AddMethodCandidate - Adds a named decl (which is some kind of 4019/// method) as a method candidate to the given overload set. 4020void Sema::AddMethodCandidate(DeclAccessPair FoundDecl, 4021 QualType ObjectType, 4022 Expr::Classification ObjectClassification, 4023 Expr **Args, unsigned NumArgs, 4024 OverloadCandidateSet& CandidateSet, 4025 bool SuppressUserConversions) { 4026 NamedDecl *Decl = FoundDecl.getDecl(); 4027 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(Decl->getDeclContext()); 4028 4029 if (isa<UsingShadowDecl>(Decl)) 4030 Decl = cast<UsingShadowDecl>(Decl)->getTargetDecl(); 4031 4032 if (FunctionTemplateDecl *TD = dyn_cast<FunctionTemplateDecl>(Decl)) { 4033 assert(isa<CXXMethodDecl>(TD->getTemplatedDecl()) && 4034 "Expected a member function template"); 4035 AddMethodTemplateCandidate(TD, FoundDecl, ActingContext, 4036 /*ExplicitArgs*/ 0, 4037 ObjectType, ObjectClassification, Args, NumArgs, 4038 CandidateSet, 4039 SuppressUserConversions); 4040 } else { 4041 AddMethodCandidate(cast<CXXMethodDecl>(Decl), FoundDecl, ActingContext, 4042 ObjectType, ObjectClassification, Args, NumArgs, 4043 CandidateSet, SuppressUserConversions); 4044 } 4045} 4046 4047/// AddMethodCandidate - Adds the given C++ member function to the set 4048/// of candidate functions, using the given function call arguments 4049/// and the object argument (@c Object). For example, in a call 4050/// @c o.f(a1,a2), @c Object will contain @c o and @c Args will contain 4051/// both @c a1 and @c a2. If @p SuppressUserConversions, then don't 4052/// allow user-defined conversions via constructors or conversion 4053/// operators. 4054void 4055Sema::AddMethodCandidate(CXXMethodDecl *Method, DeclAccessPair FoundDecl, 4056 CXXRecordDecl *ActingContext, QualType ObjectType, 4057 Expr::Classification ObjectClassification, 4058 Expr **Args, unsigned NumArgs, 4059 OverloadCandidateSet& CandidateSet, 4060 bool SuppressUserConversions) { 4061 const FunctionProtoType* Proto 4062 = dyn_cast<FunctionProtoType>(Method->getType()->getAs<FunctionType>()); 4063 assert(Proto && "Methods without a prototype cannot be overloaded"); 4064 assert(!isa<CXXConstructorDecl>(Method) && 4065 "Use AddOverloadCandidate for constructors"); 4066 4067 if (!CandidateSet.isNewCandidate(Method)) 4068 return; 4069 4070 // Overload resolution is always an unevaluated context. 4071 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4072 4073 // Add this candidate 4074 CandidateSet.push_back(OverloadCandidate()); 4075 OverloadCandidate& Candidate = CandidateSet.back(); 4076 Candidate.FoundDecl = FoundDecl; 4077 Candidate.Function = Method; 4078 Candidate.IsSurrogate = false; 4079 Candidate.IgnoreObjectArgument = false; 4080 Candidate.ExplicitCallArguments = NumArgs; 4081 4082 unsigned NumArgsInProto = Proto->getNumArgs(); 4083 4084 // (C++ 13.3.2p2): A candidate function having fewer than m 4085 // parameters is viable only if it has an ellipsis in its parameter 4086 // list (8.3.5). 4087 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4088 Candidate.Viable = false; 4089 Candidate.FailureKind = ovl_fail_too_many_arguments; 4090 return; 4091 } 4092 4093 // (C++ 13.3.2p2): A candidate function having more than m parameters 4094 // is viable only if the (m+1)st parameter has a default argument 4095 // (8.3.6). For the purposes of overload resolution, the 4096 // parameter list is truncated on the right, so that there are 4097 // exactly m parameters. 4098 unsigned MinRequiredArgs = Method->getMinRequiredArguments(); 4099 if (NumArgs < MinRequiredArgs) { 4100 // Not enough arguments. 4101 Candidate.Viable = false; 4102 Candidate.FailureKind = ovl_fail_too_few_arguments; 4103 return; 4104 } 4105 4106 Candidate.Viable = true; 4107 Candidate.Conversions.resize(NumArgs + 1); 4108 4109 if (Method->isStatic() || ObjectType.isNull()) 4110 // The implicit object argument is ignored. 4111 Candidate.IgnoreObjectArgument = true; 4112 else { 4113 // Determine the implicit conversion sequence for the object 4114 // parameter. 4115 Candidate.Conversions[0] 4116 = TryObjectArgumentInitialization(*this, ObjectType, ObjectClassification, 4117 Method, ActingContext); 4118 if (Candidate.Conversions[0].isBad()) { 4119 Candidate.Viable = false; 4120 Candidate.FailureKind = ovl_fail_bad_conversion; 4121 return; 4122 } 4123 } 4124 4125 // Determine the implicit conversion sequences for each of the 4126 // arguments. 4127 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4128 if (ArgIdx < NumArgsInProto) { 4129 // (C++ 13.3.2p3): for F to be a viable function, there shall 4130 // exist for each argument an implicit conversion sequence 4131 // (13.3.3.1) that converts that argument to the corresponding 4132 // parameter of F. 4133 QualType ParamType = Proto->getArgType(ArgIdx); 4134 Candidate.Conversions[ArgIdx + 1] 4135 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4136 SuppressUserConversions, 4137 /*InOverloadResolution=*/true); 4138 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4139 Candidate.Viable = false; 4140 Candidate.FailureKind = ovl_fail_bad_conversion; 4141 break; 4142 } 4143 } else { 4144 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4145 // argument for which there is no corresponding parameter is 4146 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4147 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4148 } 4149 } 4150} 4151 4152/// \brief Add a C++ member function template as a candidate to the candidate 4153/// set, using template argument deduction to produce an appropriate member 4154/// function template specialization. 4155void 4156Sema::AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl, 4157 DeclAccessPair FoundDecl, 4158 CXXRecordDecl *ActingContext, 4159 TemplateArgumentListInfo *ExplicitTemplateArgs, 4160 QualType ObjectType, 4161 Expr::Classification ObjectClassification, 4162 Expr **Args, unsigned NumArgs, 4163 OverloadCandidateSet& CandidateSet, 4164 bool SuppressUserConversions) { 4165 if (!CandidateSet.isNewCandidate(MethodTmpl)) 4166 return; 4167 4168 // C++ [over.match.funcs]p7: 4169 // In each case where a candidate is a function template, candidate 4170 // function template specializations are generated using template argument 4171 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4172 // candidate functions in the usual way.113) A given name can refer to one 4173 // or more function templates and also to a set of overloaded non-template 4174 // functions. In such a case, the candidate functions generated from each 4175 // function template are combined with the set of non-template candidate 4176 // functions. 4177 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4178 FunctionDecl *Specialization = 0; 4179 if (TemplateDeductionResult Result 4180 = DeduceTemplateArguments(MethodTmpl, ExplicitTemplateArgs, 4181 Args, NumArgs, Specialization, Info)) { 4182 CandidateSet.push_back(OverloadCandidate()); 4183 OverloadCandidate &Candidate = CandidateSet.back(); 4184 Candidate.FoundDecl = FoundDecl; 4185 Candidate.Function = MethodTmpl->getTemplatedDecl(); 4186 Candidate.Viable = false; 4187 Candidate.FailureKind = ovl_fail_bad_deduction; 4188 Candidate.IsSurrogate = false; 4189 Candidate.IgnoreObjectArgument = false; 4190 Candidate.ExplicitCallArguments = NumArgs; 4191 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4192 Info); 4193 return; 4194 } 4195 4196 // Add the function template specialization produced by template argument 4197 // deduction as a candidate. 4198 assert(Specialization && "Missing member function template specialization?"); 4199 assert(isa<CXXMethodDecl>(Specialization) && 4200 "Specialization is not a member function?"); 4201 AddMethodCandidate(cast<CXXMethodDecl>(Specialization), FoundDecl, 4202 ActingContext, ObjectType, ObjectClassification, 4203 Args, NumArgs, CandidateSet, SuppressUserConversions); 4204} 4205 4206/// \brief Add a C++ function template specialization as a candidate 4207/// in the candidate set, using template argument deduction to produce 4208/// an appropriate function template specialization. 4209void 4210Sema::AddTemplateOverloadCandidate(FunctionTemplateDecl *FunctionTemplate, 4211 DeclAccessPair FoundDecl, 4212 TemplateArgumentListInfo *ExplicitTemplateArgs, 4213 Expr **Args, unsigned NumArgs, 4214 OverloadCandidateSet& CandidateSet, 4215 bool SuppressUserConversions) { 4216 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4217 return; 4218 4219 // C++ [over.match.funcs]p7: 4220 // In each case where a candidate is a function template, candidate 4221 // function template specializations are generated using template argument 4222 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4223 // candidate functions in the usual way.113) A given name can refer to one 4224 // or more function templates and also to a set of overloaded non-template 4225 // functions. In such a case, the candidate functions generated from each 4226 // function template are combined with the set of non-template candidate 4227 // functions. 4228 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4229 FunctionDecl *Specialization = 0; 4230 if (TemplateDeductionResult Result 4231 = DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs, 4232 Args, NumArgs, Specialization, Info)) { 4233 CandidateSet.push_back(OverloadCandidate()); 4234 OverloadCandidate &Candidate = CandidateSet.back(); 4235 Candidate.FoundDecl = FoundDecl; 4236 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4237 Candidate.Viable = false; 4238 Candidate.FailureKind = ovl_fail_bad_deduction; 4239 Candidate.IsSurrogate = false; 4240 Candidate.IgnoreObjectArgument = false; 4241 Candidate.ExplicitCallArguments = NumArgs; 4242 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4243 Info); 4244 return; 4245 } 4246 4247 // Add the function template specialization produced by template argument 4248 // deduction as a candidate. 4249 assert(Specialization && "Missing function template specialization?"); 4250 AddOverloadCandidate(Specialization, FoundDecl, Args, NumArgs, CandidateSet, 4251 SuppressUserConversions); 4252} 4253 4254/// AddConversionCandidate - Add a C++ conversion function as a 4255/// candidate in the candidate set (C++ [over.match.conv], 4256/// C++ [over.match.copy]). From is the expression we're converting from, 4257/// and ToType is the type that we're eventually trying to convert to 4258/// (which may or may not be the same type as the type that the 4259/// conversion function produces). 4260void 4261Sema::AddConversionCandidate(CXXConversionDecl *Conversion, 4262 DeclAccessPair FoundDecl, 4263 CXXRecordDecl *ActingContext, 4264 Expr *From, QualType ToType, 4265 OverloadCandidateSet& CandidateSet) { 4266 assert(!Conversion->getDescribedFunctionTemplate() && 4267 "Conversion function templates use AddTemplateConversionCandidate"); 4268 QualType ConvType = Conversion->getConversionType().getNonReferenceType(); 4269 if (!CandidateSet.isNewCandidate(Conversion)) 4270 return; 4271 4272 // Overload resolution is always an unevaluated context. 4273 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4274 4275 // Add this candidate 4276 CandidateSet.push_back(OverloadCandidate()); 4277 OverloadCandidate& Candidate = CandidateSet.back(); 4278 Candidate.FoundDecl = FoundDecl; 4279 Candidate.Function = Conversion; 4280 Candidate.IsSurrogate = false; 4281 Candidate.IgnoreObjectArgument = false; 4282 Candidate.FinalConversion.setAsIdentityConversion(); 4283 Candidate.FinalConversion.setFromType(ConvType); 4284 Candidate.FinalConversion.setAllToTypes(ToType); 4285 Candidate.Viable = true; 4286 Candidate.Conversions.resize(1); 4287 Candidate.ExplicitCallArguments = 1; 4288 4289 // C++ [over.match.funcs]p4: 4290 // For conversion functions, the function is considered to be a member of 4291 // the class of the implicit implied object argument for the purpose of 4292 // defining the type of the implicit object parameter. 4293 // 4294 // Determine the implicit conversion sequence for the implicit 4295 // object parameter. 4296 QualType ImplicitParamType = From->getType(); 4297 if (const PointerType *FromPtrType = ImplicitParamType->getAs<PointerType>()) 4298 ImplicitParamType = FromPtrType->getPointeeType(); 4299 CXXRecordDecl *ConversionContext 4300 = cast<CXXRecordDecl>(ImplicitParamType->getAs<RecordType>()->getDecl()); 4301 4302 Candidate.Conversions[0] 4303 = TryObjectArgumentInitialization(*this, From->getType(), 4304 From->Classify(Context), 4305 Conversion, ConversionContext); 4306 4307 if (Candidate.Conversions[0].isBad()) { 4308 Candidate.Viable = false; 4309 Candidate.FailureKind = ovl_fail_bad_conversion; 4310 return; 4311 } 4312 4313 // We won't go through a user-define type conversion function to convert a 4314 // derived to base as such conversions are given Conversion Rank. They only 4315 // go through a copy constructor. 13.3.3.1.2-p4 [over.ics.user] 4316 QualType FromCanon 4317 = Context.getCanonicalType(From->getType().getUnqualifiedType()); 4318 QualType ToCanon = Context.getCanonicalType(ToType).getUnqualifiedType(); 4319 if (FromCanon == ToCanon || IsDerivedFrom(FromCanon, ToCanon)) { 4320 Candidate.Viable = false; 4321 Candidate.FailureKind = ovl_fail_trivial_conversion; 4322 return; 4323 } 4324 4325 // To determine what the conversion from the result of calling the 4326 // conversion function to the type we're eventually trying to 4327 // convert to (ToType), we need to synthesize a call to the 4328 // conversion function and attempt copy initialization from it. This 4329 // makes sure that we get the right semantics with respect to 4330 // lvalues/rvalues and the type. Fortunately, we can allocate this 4331 // call on the stack and we don't need its arguments to be 4332 // well-formed. 4333 DeclRefExpr ConversionRef(Conversion, Conversion->getType(), 4334 VK_LValue, From->getLocStart()); 4335 ImplicitCastExpr ConversionFn(ImplicitCastExpr::OnStack, 4336 Context.getPointerType(Conversion->getType()), 4337 CK_FunctionToPointerDecay, 4338 &ConversionRef, VK_RValue); 4339 4340 QualType CallResultType 4341 = Conversion->getConversionType().getNonLValueExprType(Context); 4342 if (RequireCompleteType(From->getLocStart(), CallResultType, 0)) { 4343 Candidate.Viable = false; 4344 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4345 return; 4346 } 4347 4348 ExprValueKind VK = Expr::getValueKindForType(Conversion->getConversionType()); 4349 4350 // Note that it is safe to allocate CallExpr on the stack here because 4351 // there are 0 arguments (i.e., nothing is allocated using ASTContext's 4352 // allocator). 4353 CallExpr Call(Context, &ConversionFn, 0, 0, CallResultType, VK, 4354 From->getLocStart()); 4355 ImplicitConversionSequence ICS = 4356 TryCopyInitialization(*this, &Call, ToType, 4357 /*SuppressUserConversions=*/true, 4358 /*InOverloadResolution=*/false); 4359 4360 switch (ICS.getKind()) { 4361 case ImplicitConversionSequence::StandardConversion: 4362 Candidate.FinalConversion = ICS.Standard; 4363 4364 // C++ [over.ics.user]p3: 4365 // If the user-defined conversion is specified by a specialization of a 4366 // conversion function template, the second standard conversion sequence 4367 // shall have exact match rank. 4368 if (Conversion->getPrimaryTemplate() && 4369 GetConversionRank(ICS.Standard.Second) != ICR_Exact_Match) { 4370 Candidate.Viable = false; 4371 Candidate.FailureKind = ovl_fail_final_conversion_not_exact; 4372 } 4373 4374 // C++0x [dcl.init.ref]p5: 4375 // In the second case, if the reference is an rvalue reference and 4376 // the second standard conversion sequence of the user-defined 4377 // conversion sequence includes an lvalue-to-rvalue conversion, the 4378 // program is ill-formed. 4379 if (ToType->isRValueReferenceType() && 4380 ICS.Standard.First == ICK_Lvalue_To_Rvalue) { 4381 Candidate.Viable = false; 4382 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4383 } 4384 break; 4385 4386 case ImplicitConversionSequence::BadConversion: 4387 Candidate.Viable = false; 4388 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4389 break; 4390 4391 default: 4392 assert(false && 4393 "Can only end up with a standard conversion sequence or failure"); 4394 } 4395} 4396 4397/// \brief Adds a conversion function template specialization 4398/// candidate to the overload set, using template argument deduction 4399/// to deduce the template arguments of the conversion function 4400/// template from the type that we are converting to (C++ 4401/// [temp.deduct.conv]). 4402void 4403Sema::AddTemplateConversionCandidate(FunctionTemplateDecl *FunctionTemplate, 4404 DeclAccessPair FoundDecl, 4405 CXXRecordDecl *ActingDC, 4406 Expr *From, QualType ToType, 4407 OverloadCandidateSet &CandidateSet) { 4408 assert(isa<CXXConversionDecl>(FunctionTemplate->getTemplatedDecl()) && 4409 "Only conversion function templates permitted here"); 4410 4411 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4412 return; 4413 4414 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4415 CXXConversionDecl *Specialization = 0; 4416 if (TemplateDeductionResult Result 4417 = DeduceTemplateArguments(FunctionTemplate, ToType, 4418 Specialization, Info)) { 4419 CandidateSet.push_back(OverloadCandidate()); 4420 OverloadCandidate &Candidate = CandidateSet.back(); 4421 Candidate.FoundDecl = FoundDecl; 4422 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4423 Candidate.Viable = false; 4424 Candidate.FailureKind = ovl_fail_bad_deduction; 4425 Candidate.IsSurrogate = false; 4426 Candidate.IgnoreObjectArgument = false; 4427 Candidate.ExplicitCallArguments = 1; 4428 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4429 Info); 4430 return; 4431 } 4432 4433 // Add the conversion function template specialization produced by 4434 // template argument deduction as a candidate. 4435 assert(Specialization && "Missing function template specialization?"); 4436 AddConversionCandidate(Specialization, FoundDecl, ActingDC, From, ToType, 4437 CandidateSet); 4438} 4439 4440/// AddSurrogateCandidate - Adds a "surrogate" candidate function that 4441/// converts the given @c Object to a function pointer via the 4442/// conversion function @c Conversion, and then attempts to call it 4443/// with the given arguments (C++ [over.call.object]p2-4). Proto is 4444/// the type of function that we'll eventually be calling. 4445void Sema::AddSurrogateCandidate(CXXConversionDecl *Conversion, 4446 DeclAccessPair FoundDecl, 4447 CXXRecordDecl *ActingContext, 4448 const FunctionProtoType *Proto, 4449 Expr *Object, 4450 Expr **Args, unsigned NumArgs, 4451 OverloadCandidateSet& CandidateSet) { 4452 if (!CandidateSet.isNewCandidate(Conversion)) 4453 return; 4454 4455 // Overload resolution is always an unevaluated context. 4456 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4457 4458 CandidateSet.push_back(OverloadCandidate()); 4459 OverloadCandidate& Candidate = CandidateSet.back(); 4460 Candidate.FoundDecl = FoundDecl; 4461 Candidate.Function = 0; 4462 Candidate.Surrogate = Conversion; 4463 Candidate.Viable = true; 4464 Candidate.IsSurrogate = true; 4465 Candidate.IgnoreObjectArgument = false; 4466 Candidate.Conversions.resize(NumArgs + 1); 4467 Candidate.ExplicitCallArguments = NumArgs; 4468 4469 // Determine the implicit conversion sequence for the implicit 4470 // object parameter. 4471 ImplicitConversionSequence ObjectInit 4472 = TryObjectArgumentInitialization(*this, Object->getType(), 4473 Object->Classify(Context), 4474 Conversion, ActingContext); 4475 if (ObjectInit.isBad()) { 4476 Candidate.Viable = false; 4477 Candidate.FailureKind = ovl_fail_bad_conversion; 4478 Candidate.Conversions[0] = ObjectInit; 4479 return; 4480 } 4481 4482 // The first conversion is actually a user-defined conversion whose 4483 // first conversion is ObjectInit's standard conversion (which is 4484 // effectively a reference binding). Record it as such. 4485 Candidate.Conversions[0].setUserDefined(); 4486 Candidate.Conversions[0].UserDefined.Before = ObjectInit.Standard; 4487 Candidate.Conversions[0].UserDefined.EllipsisConversion = false; 4488 Candidate.Conversions[0].UserDefined.ConversionFunction = Conversion; 4489 Candidate.Conversions[0].UserDefined.FoundConversionFunction 4490 = FoundDecl.getDecl(); 4491 Candidate.Conversions[0].UserDefined.After 4492 = Candidate.Conversions[0].UserDefined.Before; 4493 Candidate.Conversions[0].UserDefined.After.setAsIdentityConversion(); 4494 4495 // Find the 4496 unsigned NumArgsInProto = Proto->getNumArgs(); 4497 4498 // (C++ 13.3.2p2): A candidate function having fewer than m 4499 // parameters is viable only if it has an ellipsis in its parameter 4500 // list (8.3.5). 4501 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4502 Candidate.Viable = false; 4503 Candidate.FailureKind = ovl_fail_too_many_arguments; 4504 return; 4505 } 4506 4507 // Function types don't have any default arguments, so just check if 4508 // we have enough arguments. 4509 if (NumArgs < NumArgsInProto) { 4510 // Not enough arguments. 4511 Candidate.Viable = false; 4512 Candidate.FailureKind = ovl_fail_too_few_arguments; 4513 return; 4514 } 4515 4516 // Determine the implicit conversion sequences for each of the 4517 // arguments. 4518 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4519 if (ArgIdx < NumArgsInProto) { 4520 // (C++ 13.3.2p3): for F to be a viable function, there shall 4521 // exist for each argument an implicit conversion sequence 4522 // (13.3.3.1) that converts that argument to the corresponding 4523 // parameter of F. 4524 QualType ParamType = Proto->getArgType(ArgIdx); 4525 Candidate.Conversions[ArgIdx + 1] 4526 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4527 /*SuppressUserConversions=*/false, 4528 /*InOverloadResolution=*/false); 4529 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4530 Candidate.Viable = false; 4531 Candidate.FailureKind = ovl_fail_bad_conversion; 4532 break; 4533 } 4534 } else { 4535 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4536 // argument for which there is no corresponding parameter is 4537 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4538 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4539 } 4540 } 4541} 4542 4543/// \brief Add overload candidates for overloaded operators that are 4544/// member functions. 4545/// 4546/// Add the overloaded operator candidates that are member functions 4547/// for the operator Op that was used in an operator expression such 4548/// as "x Op y". , Args/NumArgs provides the operator arguments, and 4549/// CandidateSet will store the added overload candidates. (C++ 4550/// [over.match.oper]). 4551void Sema::AddMemberOperatorCandidates(OverloadedOperatorKind Op, 4552 SourceLocation OpLoc, 4553 Expr **Args, unsigned NumArgs, 4554 OverloadCandidateSet& CandidateSet, 4555 SourceRange OpRange) { 4556 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 4557 4558 // C++ [over.match.oper]p3: 4559 // For a unary operator @ with an operand of a type whose 4560 // cv-unqualified version is T1, and for a binary operator @ with 4561 // a left operand of a type whose cv-unqualified version is T1 and 4562 // a right operand of a type whose cv-unqualified version is T2, 4563 // three sets of candidate functions, designated member 4564 // candidates, non-member candidates and built-in candidates, are 4565 // constructed as follows: 4566 QualType T1 = Args[0]->getType(); 4567 4568 // -- If T1 is a class type, the set of member candidates is the 4569 // result of the qualified lookup of T1::operator@ 4570 // (13.3.1.1.1); otherwise, the set of member candidates is 4571 // empty. 4572 if (const RecordType *T1Rec = T1->getAs<RecordType>()) { 4573 // Complete the type if it can be completed. Otherwise, we're done. 4574 if (RequireCompleteType(OpLoc, T1, PDiag())) 4575 return; 4576 4577 LookupResult Operators(*this, OpName, OpLoc, LookupOrdinaryName); 4578 LookupQualifiedName(Operators, T1Rec->getDecl()); 4579 Operators.suppressDiagnostics(); 4580 4581 for (LookupResult::iterator Oper = Operators.begin(), 4582 OperEnd = Operators.end(); 4583 Oper != OperEnd; 4584 ++Oper) 4585 AddMethodCandidate(Oper.getPair(), Args[0]->getType(), 4586 Args[0]->Classify(Context), Args + 1, NumArgs - 1, 4587 CandidateSet, 4588 /* SuppressUserConversions = */ false); 4589 } 4590} 4591 4592/// AddBuiltinCandidate - Add a candidate for a built-in 4593/// operator. ResultTy and ParamTys are the result and parameter types 4594/// of the built-in candidate, respectively. Args and NumArgs are the 4595/// arguments being passed to the candidate. IsAssignmentOperator 4596/// should be true when this built-in candidate is an assignment 4597/// operator. NumContextualBoolArguments is the number of arguments 4598/// (at the beginning of the argument list) that will be contextually 4599/// converted to bool. 4600void Sema::AddBuiltinCandidate(QualType ResultTy, QualType *ParamTys, 4601 Expr **Args, unsigned NumArgs, 4602 OverloadCandidateSet& CandidateSet, 4603 bool IsAssignmentOperator, 4604 unsigned NumContextualBoolArguments) { 4605 // Overload resolution is always an unevaluated context. 4606 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4607 4608 // Add this candidate 4609 CandidateSet.push_back(OverloadCandidate()); 4610 OverloadCandidate& Candidate = CandidateSet.back(); 4611 Candidate.FoundDecl = DeclAccessPair::make(0, AS_none); 4612 Candidate.Function = 0; 4613 Candidate.IsSurrogate = false; 4614 Candidate.IgnoreObjectArgument = false; 4615 Candidate.BuiltinTypes.ResultTy = ResultTy; 4616 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 4617 Candidate.BuiltinTypes.ParamTypes[ArgIdx] = ParamTys[ArgIdx]; 4618 4619 // Determine the implicit conversion sequences for each of the 4620 // arguments. 4621 Candidate.Viable = true; 4622 Candidate.Conversions.resize(NumArgs); 4623 Candidate.ExplicitCallArguments = NumArgs; 4624 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4625 // C++ [over.match.oper]p4: 4626 // For the built-in assignment operators, conversions of the 4627 // left operand are restricted as follows: 4628 // -- no temporaries are introduced to hold the left operand, and 4629 // -- no user-defined conversions are applied to the left 4630 // operand to achieve a type match with the left-most 4631 // parameter of a built-in candidate. 4632 // 4633 // We block these conversions by turning off user-defined 4634 // conversions, since that is the only way that initialization of 4635 // a reference to a non-class type can occur from something that 4636 // is not of the same type. 4637 if (ArgIdx < NumContextualBoolArguments) { 4638 assert(ParamTys[ArgIdx] == Context.BoolTy && 4639 "Contextual conversion to bool requires bool type"); 4640 Candidate.Conversions[ArgIdx] 4641 = TryContextuallyConvertToBool(*this, Args[ArgIdx]); 4642 } else { 4643 Candidate.Conversions[ArgIdx] 4644 = TryCopyInitialization(*this, Args[ArgIdx], ParamTys[ArgIdx], 4645 ArgIdx == 0 && IsAssignmentOperator, 4646 /*InOverloadResolution=*/false); 4647 } 4648 if (Candidate.Conversions[ArgIdx].isBad()) { 4649 Candidate.Viable = false; 4650 Candidate.FailureKind = ovl_fail_bad_conversion; 4651 break; 4652 } 4653 } 4654} 4655 4656/// BuiltinCandidateTypeSet - A set of types that will be used for the 4657/// candidate operator functions for built-in operators (C++ 4658/// [over.built]). The types are separated into pointer types and 4659/// enumeration types. 4660class BuiltinCandidateTypeSet { 4661 /// TypeSet - A set of types. 4662 typedef llvm::SmallPtrSet<QualType, 8> TypeSet; 4663 4664 /// PointerTypes - The set of pointer types that will be used in the 4665 /// built-in candidates. 4666 TypeSet PointerTypes; 4667 4668 /// MemberPointerTypes - The set of member pointer types that will be 4669 /// used in the built-in candidates. 4670 TypeSet MemberPointerTypes; 4671 4672 /// EnumerationTypes - The set of enumeration types that will be 4673 /// used in the built-in candidates. 4674 TypeSet EnumerationTypes; 4675 4676 /// \brief The set of vector types that will be used in the built-in 4677 /// candidates. 4678 TypeSet VectorTypes; 4679 4680 /// \brief A flag indicating non-record types are viable candidates 4681 bool HasNonRecordTypes; 4682 4683 /// \brief A flag indicating whether either arithmetic or enumeration types 4684 /// were present in the candidate set. 4685 bool HasArithmeticOrEnumeralTypes; 4686 4687 /// Sema - The semantic analysis instance where we are building the 4688 /// candidate type set. 4689 Sema &SemaRef; 4690 4691 /// Context - The AST context in which we will build the type sets. 4692 ASTContext &Context; 4693 4694 bool AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 4695 const Qualifiers &VisibleQuals); 4696 bool AddMemberPointerWithMoreQualifiedTypeVariants(QualType Ty); 4697 4698public: 4699 /// iterator - Iterates through the types that are part of the set. 4700 typedef TypeSet::iterator iterator; 4701 4702 BuiltinCandidateTypeSet(Sema &SemaRef) 4703 : HasNonRecordTypes(false), 4704 HasArithmeticOrEnumeralTypes(false), 4705 SemaRef(SemaRef), 4706 Context(SemaRef.Context) { } 4707 4708 void AddTypesConvertedFrom(QualType Ty, 4709 SourceLocation Loc, 4710 bool AllowUserConversions, 4711 bool AllowExplicitConversions, 4712 const Qualifiers &VisibleTypeConversionsQuals); 4713 4714 /// pointer_begin - First pointer type found; 4715 iterator pointer_begin() { return PointerTypes.begin(); } 4716 4717 /// pointer_end - Past the last pointer type found; 4718 iterator pointer_end() { return PointerTypes.end(); } 4719 4720 /// member_pointer_begin - First member pointer type found; 4721 iterator member_pointer_begin() { return MemberPointerTypes.begin(); } 4722 4723 /// member_pointer_end - Past the last member pointer type found; 4724 iterator member_pointer_end() { return MemberPointerTypes.end(); } 4725 4726 /// enumeration_begin - First enumeration type found; 4727 iterator enumeration_begin() { return EnumerationTypes.begin(); } 4728 4729 /// enumeration_end - Past the last enumeration type found; 4730 iterator enumeration_end() { return EnumerationTypes.end(); } 4731 4732 iterator vector_begin() { return VectorTypes.begin(); } 4733 iterator vector_end() { return VectorTypes.end(); } 4734 4735 bool hasNonRecordTypes() { return HasNonRecordTypes; } 4736 bool hasArithmeticOrEnumeralTypes() { return HasArithmeticOrEnumeralTypes; } 4737}; 4738 4739/// AddPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty to 4740/// the set of pointer types along with any more-qualified variants of 4741/// that type. For example, if @p Ty is "int const *", this routine 4742/// will add "int const *", "int const volatile *", "int const 4743/// restrict *", and "int const volatile restrict *" to the set of 4744/// pointer types. Returns true if the add of @p Ty itself succeeded, 4745/// false otherwise. 4746/// 4747/// FIXME: what to do about extended qualifiers? 4748bool 4749BuiltinCandidateTypeSet::AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 4750 const Qualifiers &VisibleQuals) { 4751 4752 // Insert this type. 4753 if (!PointerTypes.insert(Ty)) 4754 return false; 4755 4756 QualType PointeeTy; 4757 const PointerType *PointerTy = Ty->getAs<PointerType>(); 4758 bool buildObjCPtr = false; 4759 if (!PointerTy) { 4760 if (const ObjCObjectPointerType *PTy = Ty->getAs<ObjCObjectPointerType>()) { 4761 PointeeTy = PTy->getPointeeType(); 4762 buildObjCPtr = true; 4763 } 4764 else 4765 assert(false && "type was not a pointer type!"); 4766 } 4767 else 4768 PointeeTy = PointerTy->getPointeeType(); 4769 4770 // Don't add qualified variants of arrays. For one, they're not allowed 4771 // (the qualifier would sink to the element type), and for another, the 4772 // only overload situation where it matters is subscript or pointer +- int, 4773 // and those shouldn't have qualifier variants anyway. 4774 if (PointeeTy->isArrayType()) 4775 return true; 4776 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 4777 if (const ConstantArrayType *Array =Context.getAsConstantArrayType(PointeeTy)) 4778 BaseCVR = Array->getElementType().getCVRQualifiers(); 4779 bool hasVolatile = VisibleQuals.hasVolatile(); 4780 bool hasRestrict = VisibleQuals.hasRestrict(); 4781 4782 // Iterate through all strict supersets of BaseCVR. 4783 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 4784 if ((CVR | BaseCVR) != CVR) continue; 4785 // Skip over Volatile/Restrict if no Volatile/Restrict found anywhere 4786 // in the types. 4787 if ((CVR & Qualifiers::Volatile) && !hasVolatile) continue; 4788 if ((CVR & Qualifiers::Restrict) && !hasRestrict) continue; 4789 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 4790 if (!buildObjCPtr) 4791 PointerTypes.insert(Context.getPointerType(QPointeeTy)); 4792 else 4793 PointerTypes.insert(Context.getObjCObjectPointerType(QPointeeTy)); 4794 } 4795 4796 return true; 4797} 4798 4799/// AddMemberPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty 4800/// to the set of pointer types along with any more-qualified variants of 4801/// that type. For example, if @p Ty is "int const *", this routine 4802/// will add "int const *", "int const volatile *", "int const 4803/// restrict *", and "int const volatile restrict *" to the set of 4804/// pointer types. Returns true if the add of @p Ty itself succeeded, 4805/// false otherwise. 4806/// 4807/// FIXME: what to do about extended qualifiers? 4808bool 4809BuiltinCandidateTypeSet::AddMemberPointerWithMoreQualifiedTypeVariants( 4810 QualType Ty) { 4811 // Insert this type. 4812 if (!MemberPointerTypes.insert(Ty)) 4813 return false; 4814 4815 const MemberPointerType *PointerTy = Ty->getAs<MemberPointerType>(); 4816 assert(PointerTy && "type was not a member pointer type!"); 4817 4818 QualType PointeeTy = PointerTy->getPointeeType(); 4819 // Don't add qualified variants of arrays. For one, they're not allowed 4820 // (the qualifier would sink to the element type), and for another, the 4821 // only overload situation where it matters is subscript or pointer +- int, 4822 // and those shouldn't have qualifier variants anyway. 4823 if (PointeeTy->isArrayType()) 4824 return true; 4825 const Type *ClassTy = PointerTy->getClass(); 4826 4827 // Iterate through all strict supersets of the pointee type's CVR 4828 // qualifiers. 4829 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 4830 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 4831 if ((CVR | BaseCVR) != CVR) continue; 4832 4833 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 4834 MemberPointerTypes.insert( 4835 Context.getMemberPointerType(QPointeeTy, ClassTy)); 4836 } 4837 4838 return true; 4839} 4840 4841/// AddTypesConvertedFrom - Add each of the types to which the type @p 4842/// Ty can be implicit converted to the given set of @p Types. We're 4843/// primarily interested in pointer types and enumeration types. We also 4844/// take member pointer types, for the conditional operator. 4845/// AllowUserConversions is true if we should look at the conversion 4846/// functions of a class type, and AllowExplicitConversions if we 4847/// should also include the explicit conversion functions of a class 4848/// type. 4849void 4850BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty, 4851 SourceLocation Loc, 4852 bool AllowUserConversions, 4853 bool AllowExplicitConversions, 4854 const Qualifiers &VisibleQuals) { 4855 // Only deal with canonical types. 4856 Ty = Context.getCanonicalType(Ty); 4857 4858 // Look through reference types; they aren't part of the type of an 4859 // expression for the purposes of conversions. 4860 if (const ReferenceType *RefTy = Ty->getAs<ReferenceType>()) 4861 Ty = RefTy->getPointeeType(); 4862 4863 // If we're dealing with an array type, decay to the pointer. 4864 if (Ty->isArrayType()) 4865 Ty = SemaRef.Context.getArrayDecayedType(Ty); 4866 4867 // Otherwise, we don't care about qualifiers on the type. 4868 Ty = Ty.getLocalUnqualifiedType(); 4869 4870 // Flag if we ever add a non-record type. 4871 const RecordType *TyRec = Ty->getAs<RecordType>(); 4872 HasNonRecordTypes = HasNonRecordTypes || !TyRec; 4873 4874 // Flag if we encounter an arithmetic type. 4875 HasArithmeticOrEnumeralTypes = 4876 HasArithmeticOrEnumeralTypes || Ty->isArithmeticType(); 4877 4878 if (Ty->isObjCIdType() || Ty->isObjCClassType()) 4879 PointerTypes.insert(Ty); 4880 else if (Ty->getAs<PointerType>() || Ty->getAs<ObjCObjectPointerType>()) { 4881 // Insert our type, and its more-qualified variants, into the set 4882 // of types. 4883 if (!AddPointerWithMoreQualifiedTypeVariants(Ty, VisibleQuals)) 4884 return; 4885 } else if (Ty->isMemberPointerType()) { 4886 // Member pointers are far easier, since the pointee can't be converted. 4887 if (!AddMemberPointerWithMoreQualifiedTypeVariants(Ty)) 4888 return; 4889 } else if (Ty->isEnumeralType()) { 4890 HasArithmeticOrEnumeralTypes = true; 4891 EnumerationTypes.insert(Ty); 4892 } else if (Ty->isVectorType()) { 4893 // We treat vector types as arithmetic types in many contexts as an 4894 // extension. 4895 HasArithmeticOrEnumeralTypes = true; 4896 VectorTypes.insert(Ty); 4897 } else if (AllowUserConversions && TyRec) { 4898 // No conversion functions in incomplete types. 4899 if (SemaRef.RequireCompleteType(Loc, Ty, 0)) 4900 return; 4901 4902 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 4903 const UnresolvedSetImpl *Conversions 4904 = ClassDecl->getVisibleConversionFunctions(); 4905 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 4906 E = Conversions->end(); I != E; ++I) { 4907 NamedDecl *D = I.getDecl(); 4908 if (isa<UsingShadowDecl>(D)) 4909 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 4910 4911 // Skip conversion function templates; they don't tell us anything 4912 // about which builtin types we can convert to. 4913 if (isa<FunctionTemplateDecl>(D)) 4914 continue; 4915 4916 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 4917 if (AllowExplicitConversions || !Conv->isExplicit()) { 4918 AddTypesConvertedFrom(Conv->getConversionType(), Loc, false, false, 4919 VisibleQuals); 4920 } 4921 } 4922 } 4923} 4924 4925/// \brief Helper function for AddBuiltinOperatorCandidates() that adds 4926/// the volatile- and non-volatile-qualified assignment operators for the 4927/// given type to the candidate set. 4928static void AddBuiltinAssignmentOperatorCandidates(Sema &S, 4929 QualType T, 4930 Expr **Args, 4931 unsigned NumArgs, 4932 OverloadCandidateSet &CandidateSet) { 4933 QualType ParamTypes[2]; 4934 4935 // T& operator=(T&, T) 4936 ParamTypes[0] = S.Context.getLValueReferenceType(T); 4937 ParamTypes[1] = T; 4938 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 4939 /*IsAssignmentOperator=*/true); 4940 4941 if (!S.Context.getCanonicalType(T).isVolatileQualified()) { 4942 // volatile T& operator=(volatile T&, T) 4943 ParamTypes[0] 4944 = S.Context.getLValueReferenceType(S.Context.getVolatileType(T)); 4945 ParamTypes[1] = T; 4946 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 4947 /*IsAssignmentOperator=*/true); 4948 } 4949} 4950 4951/// CollectVRQualifiers - This routine returns Volatile/Restrict qualifiers, 4952/// if any, found in visible type conversion functions found in ArgExpr's type. 4953static Qualifiers CollectVRQualifiers(ASTContext &Context, Expr* ArgExpr) { 4954 Qualifiers VRQuals; 4955 const RecordType *TyRec; 4956 if (const MemberPointerType *RHSMPType = 4957 ArgExpr->getType()->getAs<MemberPointerType>()) 4958 TyRec = RHSMPType->getClass()->getAs<RecordType>(); 4959 else 4960 TyRec = ArgExpr->getType()->getAs<RecordType>(); 4961 if (!TyRec) { 4962 // Just to be safe, assume the worst case. 4963 VRQuals.addVolatile(); 4964 VRQuals.addRestrict(); 4965 return VRQuals; 4966 } 4967 4968 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 4969 if (!ClassDecl->hasDefinition()) 4970 return VRQuals; 4971 4972 const UnresolvedSetImpl *Conversions = 4973 ClassDecl->getVisibleConversionFunctions(); 4974 4975 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 4976 E = Conversions->end(); I != E; ++I) { 4977 NamedDecl *D = I.getDecl(); 4978 if (isa<UsingShadowDecl>(D)) 4979 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 4980 if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(D)) { 4981 QualType CanTy = Context.getCanonicalType(Conv->getConversionType()); 4982 if (const ReferenceType *ResTypeRef = CanTy->getAs<ReferenceType>()) 4983 CanTy = ResTypeRef->getPointeeType(); 4984 // Need to go down the pointer/mempointer chain and add qualifiers 4985 // as see them. 4986 bool done = false; 4987 while (!done) { 4988 if (const PointerType *ResTypePtr = CanTy->getAs<PointerType>()) 4989 CanTy = ResTypePtr->getPointeeType(); 4990 else if (const MemberPointerType *ResTypeMPtr = 4991 CanTy->getAs<MemberPointerType>()) 4992 CanTy = ResTypeMPtr->getPointeeType(); 4993 else 4994 done = true; 4995 if (CanTy.isVolatileQualified()) 4996 VRQuals.addVolatile(); 4997 if (CanTy.isRestrictQualified()) 4998 VRQuals.addRestrict(); 4999 if (VRQuals.hasRestrict() && VRQuals.hasVolatile()) 5000 return VRQuals; 5001 } 5002 } 5003 } 5004 return VRQuals; 5005} 5006 5007namespace { 5008 5009/// \brief Helper class to manage the addition of builtin operator overload 5010/// candidates. It provides shared state and utility methods used throughout 5011/// the process, as well as a helper method to add each group of builtin 5012/// operator overloads from the standard to a candidate set. 5013class BuiltinOperatorOverloadBuilder { 5014 // Common instance state available to all overload candidate addition methods. 5015 Sema &S; 5016 Expr **Args; 5017 unsigned NumArgs; 5018 Qualifiers VisibleTypeConversionsQuals; 5019 bool HasArithmeticOrEnumeralCandidateType; 5020 llvm::SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes; 5021 OverloadCandidateSet &CandidateSet; 5022 5023 // Define some constants used to index and iterate over the arithemetic types 5024 // provided via the getArithmeticType() method below. 5025 // The "promoted arithmetic types" are the arithmetic 5026 // types are that preserved by promotion (C++ [over.built]p2). 5027 static const unsigned FirstIntegralType = 3; 5028 static const unsigned LastIntegralType = 18; 5029 static const unsigned FirstPromotedIntegralType = 3, 5030 LastPromotedIntegralType = 9; 5031 static const unsigned FirstPromotedArithmeticType = 0, 5032 LastPromotedArithmeticType = 9; 5033 static const unsigned NumArithmeticTypes = 18; 5034 5035 /// \brief Get the canonical type for a given arithmetic type index. 5036 CanQualType getArithmeticType(unsigned index) { 5037 assert(index < NumArithmeticTypes); 5038 static CanQualType ASTContext::* const 5039 ArithmeticTypes[NumArithmeticTypes] = { 5040 // Start of promoted types. 5041 &ASTContext::FloatTy, 5042 &ASTContext::DoubleTy, 5043 &ASTContext::LongDoubleTy, 5044 5045 // Start of integral types. 5046 &ASTContext::IntTy, 5047 &ASTContext::LongTy, 5048 &ASTContext::LongLongTy, 5049 &ASTContext::UnsignedIntTy, 5050 &ASTContext::UnsignedLongTy, 5051 &ASTContext::UnsignedLongLongTy, 5052 // End of promoted types. 5053 5054 &ASTContext::BoolTy, 5055 &ASTContext::CharTy, 5056 &ASTContext::WCharTy, 5057 &ASTContext::Char16Ty, 5058 &ASTContext::Char32Ty, 5059 &ASTContext::SignedCharTy, 5060 &ASTContext::ShortTy, 5061 &ASTContext::UnsignedCharTy, 5062 &ASTContext::UnsignedShortTy, 5063 // End of integral types. 5064 // FIXME: What about complex? 5065 }; 5066 return S.Context.*ArithmeticTypes[index]; 5067 } 5068 5069 /// \brief Gets the canonical type resulting from the usual arithemetic 5070 /// converions for the given arithmetic types. 5071 CanQualType getUsualArithmeticConversions(unsigned L, unsigned R) { 5072 // Accelerator table for performing the usual arithmetic conversions. 5073 // The rules are basically: 5074 // - if either is floating-point, use the wider floating-point 5075 // - if same signedness, use the higher rank 5076 // - if same size, use unsigned of the higher rank 5077 // - use the larger type 5078 // These rules, together with the axiom that higher ranks are 5079 // never smaller, are sufficient to precompute all of these results 5080 // *except* when dealing with signed types of higher rank. 5081 // (we could precompute SLL x UI for all known platforms, but it's 5082 // better not to make any assumptions). 5083 enum PromotedType { 5084 Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL, Dep=-1 5085 }; 5086 static PromotedType ConversionsTable[LastPromotedArithmeticType] 5087 [LastPromotedArithmeticType] = { 5088 /* Flt*/ { Flt, Dbl, LDbl, Flt, Flt, Flt, Flt, Flt, Flt }, 5089 /* Dbl*/ { Dbl, Dbl, LDbl, Dbl, Dbl, Dbl, Dbl, Dbl, Dbl }, 5090 /*LDbl*/ { LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl }, 5091 /* SI*/ { Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL }, 5092 /* SL*/ { Flt, Dbl, LDbl, SL, SL, SLL, Dep, UL, ULL }, 5093 /* SLL*/ { Flt, Dbl, LDbl, SLL, SLL, SLL, Dep, Dep, ULL }, 5094 /* UI*/ { Flt, Dbl, LDbl, UI, Dep, Dep, UI, UL, ULL }, 5095 /* UL*/ { Flt, Dbl, LDbl, UL, UL, Dep, UL, UL, ULL }, 5096 /* ULL*/ { Flt, Dbl, LDbl, ULL, ULL, ULL, ULL, ULL, ULL }, 5097 }; 5098 5099 assert(L < LastPromotedArithmeticType); 5100 assert(R < LastPromotedArithmeticType); 5101 int Idx = ConversionsTable[L][R]; 5102 5103 // Fast path: the table gives us a concrete answer. 5104 if (Idx != Dep) return getArithmeticType(Idx); 5105 5106 // Slow path: we need to compare widths. 5107 // An invariant is that the signed type has higher rank. 5108 CanQualType LT = getArithmeticType(L), 5109 RT = getArithmeticType(R); 5110 unsigned LW = S.Context.getIntWidth(LT), 5111 RW = S.Context.getIntWidth(RT); 5112 5113 // If they're different widths, use the signed type. 5114 if (LW > RW) return LT; 5115 else if (LW < RW) return RT; 5116 5117 // Otherwise, use the unsigned type of the signed type's rank. 5118 if (L == SL || R == SL) return S.Context.UnsignedLongTy; 5119 assert(L == SLL || R == SLL); 5120 return S.Context.UnsignedLongLongTy; 5121 } 5122 5123 /// \brief Helper method to factor out the common pattern of adding overloads 5124 /// for '++' and '--' builtin operators. 5125 void addPlusPlusMinusMinusStyleOverloads(QualType CandidateTy, 5126 bool HasVolatile) { 5127 QualType ParamTypes[2] = { 5128 S.Context.getLValueReferenceType(CandidateTy), 5129 S.Context.IntTy 5130 }; 5131 5132 // Non-volatile version. 5133 if (NumArgs == 1) 5134 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5135 else 5136 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5137 5138 // Use a heuristic to reduce number of builtin candidates in the set: 5139 // add volatile version only if there are conversions to a volatile type. 5140 if (HasVolatile) { 5141 ParamTypes[0] = 5142 S.Context.getLValueReferenceType( 5143 S.Context.getVolatileType(CandidateTy)); 5144 if (NumArgs == 1) 5145 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5146 else 5147 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5148 } 5149 } 5150 5151public: 5152 BuiltinOperatorOverloadBuilder( 5153 Sema &S, Expr **Args, unsigned NumArgs, 5154 Qualifiers VisibleTypeConversionsQuals, 5155 bool HasArithmeticOrEnumeralCandidateType, 5156 llvm::SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes, 5157 OverloadCandidateSet &CandidateSet) 5158 : S(S), Args(Args), NumArgs(NumArgs), 5159 VisibleTypeConversionsQuals(VisibleTypeConversionsQuals), 5160 HasArithmeticOrEnumeralCandidateType( 5161 HasArithmeticOrEnumeralCandidateType), 5162 CandidateTypes(CandidateTypes), 5163 CandidateSet(CandidateSet) { 5164 // Validate some of our static helper constants in debug builds. 5165 assert(getArithmeticType(FirstPromotedIntegralType) == S.Context.IntTy && 5166 "Invalid first promoted integral type"); 5167 assert(getArithmeticType(LastPromotedIntegralType - 1) 5168 == S.Context.UnsignedLongLongTy && 5169 "Invalid last promoted integral type"); 5170 assert(getArithmeticType(FirstPromotedArithmeticType) 5171 == S.Context.FloatTy && 5172 "Invalid first promoted arithmetic type"); 5173 assert(getArithmeticType(LastPromotedArithmeticType - 1) 5174 == S.Context.UnsignedLongLongTy && 5175 "Invalid last promoted arithmetic type"); 5176 } 5177 5178 // C++ [over.built]p3: 5179 // 5180 // For every pair (T, VQ), where T is an arithmetic type, and VQ 5181 // is either volatile or empty, there exist candidate operator 5182 // functions of the form 5183 // 5184 // VQ T& operator++(VQ T&); 5185 // T operator++(VQ T&, int); 5186 // 5187 // C++ [over.built]p4: 5188 // 5189 // For every pair (T, VQ), where T is an arithmetic type other 5190 // than bool, and VQ is either volatile or empty, there exist 5191 // candidate operator functions of the form 5192 // 5193 // VQ T& operator--(VQ T&); 5194 // T operator--(VQ T&, int); 5195 void addPlusPlusMinusMinusArithmeticOverloads(OverloadedOperatorKind Op) { 5196 if (!HasArithmeticOrEnumeralCandidateType) 5197 return; 5198 5199 for (unsigned Arith = (Op == OO_PlusPlus? 0 : 1); 5200 Arith < NumArithmeticTypes; ++Arith) { 5201 addPlusPlusMinusMinusStyleOverloads( 5202 getArithmeticType(Arith), 5203 VisibleTypeConversionsQuals.hasVolatile()); 5204 } 5205 } 5206 5207 // C++ [over.built]p5: 5208 // 5209 // For every pair (T, VQ), where T is a cv-qualified or 5210 // cv-unqualified object type, and VQ is either volatile or 5211 // empty, there exist candidate operator functions of the form 5212 // 5213 // T*VQ& operator++(T*VQ&); 5214 // T*VQ& operator--(T*VQ&); 5215 // T* operator++(T*VQ&, int); 5216 // T* operator--(T*VQ&, int); 5217 void addPlusPlusMinusMinusPointerOverloads() { 5218 for (BuiltinCandidateTypeSet::iterator 5219 Ptr = CandidateTypes[0].pointer_begin(), 5220 PtrEnd = CandidateTypes[0].pointer_end(); 5221 Ptr != PtrEnd; ++Ptr) { 5222 // Skip pointer types that aren't pointers to object types. 5223 if (!(*Ptr)->getPointeeType()->isObjectType()) 5224 continue; 5225 5226 addPlusPlusMinusMinusStyleOverloads(*Ptr, 5227 (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5228 VisibleTypeConversionsQuals.hasVolatile())); 5229 } 5230 } 5231 5232 // C++ [over.built]p6: 5233 // For every cv-qualified or cv-unqualified object type T, there 5234 // exist candidate operator functions of the form 5235 // 5236 // T& operator*(T*); 5237 // 5238 // C++ [over.built]p7: 5239 // For every function type T that does not have cv-qualifiers or a 5240 // ref-qualifier, there exist candidate operator functions of the form 5241 // T& operator*(T*); 5242 void addUnaryStarPointerOverloads() { 5243 for (BuiltinCandidateTypeSet::iterator 5244 Ptr = CandidateTypes[0].pointer_begin(), 5245 PtrEnd = CandidateTypes[0].pointer_end(); 5246 Ptr != PtrEnd; ++Ptr) { 5247 QualType ParamTy = *Ptr; 5248 QualType PointeeTy = ParamTy->getPointeeType(); 5249 if (!PointeeTy->isObjectType() && !PointeeTy->isFunctionType()) 5250 continue; 5251 5252 if (const FunctionProtoType *Proto =PointeeTy->getAs<FunctionProtoType>()) 5253 if (Proto->getTypeQuals() || Proto->getRefQualifier()) 5254 continue; 5255 5256 S.AddBuiltinCandidate(S.Context.getLValueReferenceType(PointeeTy), 5257 &ParamTy, Args, 1, CandidateSet); 5258 } 5259 } 5260 5261 // C++ [over.built]p9: 5262 // For every promoted arithmetic type T, there exist candidate 5263 // operator functions of the form 5264 // 5265 // T operator+(T); 5266 // T operator-(T); 5267 void addUnaryPlusOrMinusArithmeticOverloads() { 5268 if (!HasArithmeticOrEnumeralCandidateType) 5269 return; 5270 5271 for (unsigned Arith = FirstPromotedArithmeticType; 5272 Arith < LastPromotedArithmeticType; ++Arith) { 5273 QualType ArithTy = getArithmeticType(Arith); 5274 S.AddBuiltinCandidate(ArithTy, &ArithTy, Args, 1, CandidateSet); 5275 } 5276 5277 // Extension: We also add these operators for vector types. 5278 for (BuiltinCandidateTypeSet::iterator 5279 Vec = CandidateTypes[0].vector_begin(), 5280 VecEnd = CandidateTypes[0].vector_end(); 5281 Vec != VecEnd; ++Vec) { 5282 QualType VecTy = *Vec; 5283 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5284 } 5285 } 5286 5287 // C++ [over.built]p8: 5288 // For every type T, there exist candidate operator functions of 5289 // the form 5290 // 5291 // T* operator+(T*); 5292 void addUnaryPlusPointerOverloads() { 5293 for (BuiltinCandidateTypeSet::iterator 5294 Ptr = CandidateTypes[0].pointer_begin(), 5295 PtrEnd = CandidateTypes[0].pointer_end(); 5296 Ptr != PtrEnd; ++Ptr) { 5297 QualType ParamTy = *Ptr; 5298 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet); 5299 } 5300 } 5301 5302 // C++ [over.built]p10: 5303 // For every promoted integral type T, there exist candidate 5304 // operator functions of the form 5305 // 5306 // T operator~(T); 5307 void addUnaryTildePromotedIntegralOverloads() { 5308 if (!HasArithmeticOrEnumeralCandidateType) 5309 return; 5310 5311 for (unsigned Int = FirstPromotedIntegralType; 5312 Int < LastPromotedIntegralType; ++Int) { 5313 QualType IntTy = getArithmeticType(Int); 5314 S.AddBuiltinCandidate(IntTy, &IntTy, Args, 1, CandidateSet); 5315 } 5316 5317 // Extension: We also add this operator for vector types. 5318 for (BuiltinCandidateTypeSet::iterator 5319 Vec = CandidateTypes[0].vector_begin(), 5320 VecEnd = CandidateTypes[0].vector_end(); 5321 Vec != VecEnd; ++Vec) { 5322 QualType VecTy = *Vec; 5323 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5324 } 5325 } 5326 5327 // C++ [over.match.oper]p16: 5328 // For every pointer to member type T, there exist candidate operator 5329 // functions of the form 5330 // 5331 // bool operator==(T,T); 5332 // bool operator!=(T,T); 5333 void addEqualEqualOrNotEqualMemberPointerOverloads() { 5334 /// Set of (canonical) types that we've already handled. 5335 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5336 5337 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5338 for (BuiltinCandidateTypeSet::iterator 5339 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5340 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5341 MemPtr != MemPtrEnd; 5342 ++MemPtr) { 5343 // Don't add the same builtin candidate twice. 5344 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5345 continue; 5346 5347 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 5348 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5349 CandidateSet); 5350 } 5351 } 5352 } 5353 5354 // C++ [over.built]p15: 5355 // 5356 // For every pointer or enumeration type T, there exist 5357 // candidate operator functions of the form 5358 // 5359 // bool operator<(T, T); 5360 // bool operator>(T, T); 5361 // bool operator<=(T, T); 5362 // bool operator>=(T, T); 5363 // bool operator==(T, T); 5364 // bool operator!=(T, T); 5365 void addRelationalPointerOrEnumeralOverloads() { 5366 // C++ [over.built]p1: 5367 // If there is a user-written candidate with the same name and parameter 5368 // types as a built-in candidate operator function, the built-in operator 5369 // function is hidden and is not included in the set of candidate 5370 // functions. 5371 // 5372 // The text is actually in a note, but if we don't implement it then we end 5373 // up with ambiguities when the user provides an overloaded operator for 5374 // an enumeration type. Note that only enumeration types have this problem, 5375 // so we track which enumeration types we've seen operators for. Also, the 5376 // only other overloaded operator with enumeration argumenst, operator=, 5377 // cannot be overloaded for enumeration types, so this is the only place 5378 // where we must suppress candidates like this. 5379 llvm::DenseSet<std::pair<CanQualType, CanQualType> > 5380 UserDefinedBinaryOperators; 5381 5382 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5383 if (CandidateTypes[ArgIdx].enumeration_begin() != 5384 CandidateTypes[ArgIdx].enumeration_end()) { 5385 for (OverloadCandidateSet::iterator C = CandidateSet.begin(), 5386 CEnd = CandidateSet.end(); 5387 C != CEnd; ++C) { 5388 if (!C->Viable || !C->Function || C->Function->getNumParams() != 2) 5389 continue; 5390 5391 QualType FirstParamType = 5392 C->Function->getParamDecl(0)->getType().getUnqualifiedType(); 5393 QualType SecondParamType = 5394 C->Function->getParamDecl(1)->getType().getUnqualifiedType(); 5395 5396 // Skip if either parameter isn't of enumeral type. 5397 if (!FirstParamType->isEnumeralType() || 5398 !SecondParamType->isEnumeralType()) 5399 continue; 5400 5401 // Add this operator to the set of known user-defined operators. 5402 UserDefinedBinaryOperators.insert( 5403 std::make_pair(S.Context.getCanonicalType(FirstParamType), 5404 S.Context.getCanonicalType(SecondParamType))); 5405 } 5406 } 5407 } 5408 5409 /// Set of (canonical) types that we've already handled. 5410 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5411 5412 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5413 for (BuiltinCandidateTypeSet::iterator 5414 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 5415 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 5416 Ptr != PtrEnd; ++Ptr) { 5417 // Don't add the same builtin candidate twice. 5418 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5419 continue; 5420 5421 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5422 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5423 CandidateSet); 5424 } 5425 for (BuiltinCandidateTypeSet::iterator 5426 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5427 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5428 Enum != EnumEnd; ++Enum) { 5429 CanQualType CanonType = S.Context.getCanonicalType(*Enum); 5430 5431 // Don't add the same builtin candidate twice, or if a user defined 5432 // candidate exists. 5433 if (!AddedTypes.insert(CanonType) || 5434 UserDefinedBinaryOperators.count(std::make_pair(CanonType, 5435 CanonType))) 5436 continue; 5437 5438 QualType ParamTypes[2] = { *Enum, *Enum }; 5439 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5440 CandidateSet); 5441 } 5442 } 5443 } 5444 5445 // C++ [over.built]p13: 5446 // 5447 // For every cv-qualified or cv-unqualified object type T 5448 // there exist candidate operator functions of the form 5449 // 5450 // T* operator+(T*, ptrdiff_t); 5451 // T& operator[](T*, ptrdiff_t); [BELOW] 5452 // T* operator-(T*, ptrdiff_t); 5453 // T* operator+(ptrdiff_t, T*); 5454 // T& operator[](ptrdiff_t, T*); [BELOW] 5455 // 5456 // C++ [over.built]p14: 5457 // 5458 // For every T, where T is a pointer to object type, there 5459 // exist candidate operator functions of the form 5460 // 5461 // ptrdiff_t operator-(T, T); 5462 void addBinaryPlusOrMinusPointerOverloads(OverloadedOperatorKind Op) { 5463 /// Set of (canonical) types that we've already handled. 5464 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5465 5466 for (int Arg = 0; Arg < 2; ++Arg) { 5467 QualType AsymetricParamTypes[2] = { 5468 S.Context.getPointerDiffType(), 5469 S.Context.getPointerDiffType(), 5470 }; 5471 for (BuiltinCandidateTypeSet::iterator 5472 Ptr = CandidateTypes[Arg].pointer_begin(), 5473 PtrEnd = CandidateTypes[Arg].pointer_end(); 5474 Ptr != PtrEnd; ++Ptr) { 5475 QualType PointeeTy = (*Ptr)->getPointeeType(); 5476 if (!PointeeTy->isObjectType()) 5477 continue; 5478 5479 AsymetricParamTypes[Arg] = *Ptr; 5480 if (Arg == 0 || Op == OO_Plus) { 5481 // operator+(T*, ptrdiff_t) or operator-(T*, ptrdiff_t) 5482 // T* operator+(ptrdiff_t, T*); 5483 S.AddBuiltinCandidate(*Ptr, AsymetricParamTypes, Args, 2, 5484 CandidateSet); 5485 } 5486 if (Op == OO_Minus) { 5487 // ptrdiff_t operator-(T, T); 5488 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5489 continue; 5490 5491 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5492 S.AddBuiltinCandidate(S.Context.getPointerDiffType(), ParamTypes, 5493 Args, 2, CandidateSet); 5494 } 5495 } 5496 } 5497 } 5498 5499 // C++ [over.built]p12: 5500 // 5501 // For every pair of promoted arithmetic types L and R, there 5502 // exist candidate operator functions of the form 5503 // 5504 // LR operator*(L, R); 5505 // LR operator/(L, R); 5506 // LR operator+(L, R); 5507 // LR operator-(L, R); 5508 // bool operator<(L, R); 5509 // bool operator>(L, R); 5510 // bool operator<=(L, R); 5511 // bool operator>=(L, R); 5512 // bool operator==(L, R); 5513 // bool operator!=(L, R); 5514 // 5515 // where LR is the result of the usual arithmetic conversions 5516 // between types L and R. 5517 // 5518 // C++ [over.built]p24: 5519 // 5520 // For every pair of promoted arithmetic types L and R, there exist 5521 // candidate operator functions of the form 5522 // 5523 // LR operator?(bool, L, R); 5524 // 5525 // where LR is the result of the usual arithmetic conversions 5526 // between types L and R. 5527 // Our candidates ignore the first parameter. 5528 void addGenericBinaryArithmeticOverloads(bool isComparison) { 5529 if (!HasArithmeticOrEnumeralCandidateType) 5530 return; 5531 5532 for (unsigned Left = FirstPromotedArithmeticType; 5533 Left < LastPromotedArithmeticType; ++Left) { 5534 for (unsigned Right = FirstPromotedArithmeticType; 5535 Right < LastPromotedArithmeticType; ++Right) { 5536 QualType LandR[2] = { getArithmeticType(Left), 5537 getArithmeticType(Right) }; 5538 QualType Result = 5539 isComparison ? S.Context.BoolTy 5540 : getUsualArithmeticConversions(Left, Right); 5541 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5542 } 5543 } 5544 5545 // Extension: Add the binary operators ==, !=, <, <=, >=, >, *, /, and the 5546 // conditional operator for vector types. 5547 for (BuiltinCandidateTypeSet::iterator 5548 Vec1 = CandidateTypes[0].vector_begin(), 5549 Vec1End = CandidateTypes[0].vector_end(); 5550 Vec1 != Vec1End; ++Vec1) { 5551 for (BuiltinCandidateTypeSet::iterator 5552 Vec2 = CandidateTypes[1].vector_begin(), 5553 Vec2End = CandidateTypes[1].vector_end(); 5554 Vec2 != Vec2End; ++Vec2) { 5555 QualType LandR[2] = { *Vec1, *Vec2 }; 5556 QualType Result = S.Context.BoolTy; 5557 if (!isComparison) { 5558 if ((*Vec1)->isExtVectorType() || !(*Vec2)->isExtVectorType()) 5559 Result = *Vec1; 5560 else 5561 Result = *Vec2; 5562 } 5563 5564 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5565 } 5566 } 5567 } 5568 5569 // C++ [over.built]p17: 5570 // 5571 // For every pair of promoted integral types L and R, there 5572 // exist candidate operator functions of the form 5573 // 5574 // LR operator%(L, R); 5575 // LR operator&(L, R); 5576 // LR operator^(L, R); 5577 // LR operator|(L, R); 5578 // L operator<<(L, R); 5579 // L operator>>(L, R); 5580 // 5581 // where LR is the result of the usual arithmetic conversions 5582 // between types L and R. 5583 void addBinaryBitwiseArithmeticOverloads(OverloadedOperatorKind Op) { 5584 if (!HasArithmeticOrEnumeralCandidateType) 5585 return; 5586 5587 for (unsigned Left = FirstPromotedIntegralType; 5588 Left < LastPromotedIntegralType; ++Left) { 5589 for (unsigned Right = FirstPromotedIntegralType; 5590 Right < LastPromotedIntegralType; ++Right) { 5591 QualType LandR[2] = { getArithmeticType(Left), 5592 getArithmeticType(Right) }; 5593 QualType Result = (Op == OO_LessLess || Op == OO_GreaterGreater) 5594 ? LandR[0] 5595 : getUsualArithmeticConversions(Left, Right); 5596 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5597 } 5598 } 5599 } 5600 5601 // C++ [over.built]p20: 5602 // 5603 // For every pair (T, VQ), where T is an enumeration or 5604 // pointer to member type and VQ is either volatile or 5605 // empty, there exist candidate operator functions of the form 5606 // 5607 // VQ T& operator=(VQ T&, T); 5608 void addAssignmentMemberPointerOrEnumeralOverloads() { 5609 /// Set of (canonical) types that we've already handled. 5610 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5611 5612 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 5613 for (BuiltinCandidateTypeSet::iterator 5614 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5615 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5616 Enum != EnumEnd; ++Enum) { 5617 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 5618 continue; 5619 5620 AddBuiltinAssignmentOperatorCandidates(S, *Enum, Args, 2, 5621 CandidateSet); 5622 } 5623 5624 for (BuiltinCandidateTypeSet::iterator 5625 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5626 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5627 MemPtr != MemPtrEnd; ++MemPtr) { 5628 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5629 continue; 5630 5631 AddBuiltinAssignmentOperatorCandidates(S, *MemPtr, Args, 2, 5632 CandidateSet); 5633 } 5634 } 5635 } 5636 5637 // C++ [over.built]p19: 5638 // 5639 // For every pair (T, VQ), where T is any type and VQ is either 5640 // volatile or empty, there exist candidate operator functions 5641 // of the form 5642 // 5643 // T*VQ& operator=(T*VQ&, T*); 5644 // 5645 // C++ [over.built]p21: 5646 // 5647 // For every pair (T, VQ), where T is a cv-qualified or 5648 // cv-unqualified object type and VQ is either volatile or 5649 // empty, there exist candidate operator functions of the form 5650 // 5651 // T*VQ& operator+=(T*VQ&, ptrdiff_t); 5652 // T*VQ& operator-=(T*VQ&, ptrdiff_t); 5653 void addAssignmentPointerOverloads(bool isEqualOp) { 5654 /// Set of (canonical) types that we've already handled. 5655 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5656 5657 for (BuiltinCandidateTypeSet::iterator 5658 Ptr = CandidateTypes[0].pointer_begin(), 5659 PtrEnd = CandidateTypes[0].pointer_end(); 5660 Ptr != PtrEnd; ++Ptr) { 5661 // If this is operator=, keep track of the builtin candidates we added. 5662 if (isEqualOp) 5663 AddedTypes.insert(S.Context.getCanonicalType(*Ptr)); 5664 else if (!(*Ptr)->getPointeeType()->isObjectType()) 5665 continue; 5666 5667 // non-volatile version 5668 QualType ParamTypes[2] = { 5669 S.Context.getLValueReferenceType(*Ptr), 5670 isEqualOp ? *Ptr : S.Context.getPointerDiffType(), 5671 }; 5672 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5673 /*IsAssigmentOperator=*/ isEqualOp); 5674 5675 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5676 VisibleTypeConversionsQuals.hasVolatile()) { 5677 // volatile version 5678 ParamTypes[0] = 5679 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 5680 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5681 /*IsAssigmentOperator=*/isEqualOp); 5682 } 5683 } 5684 5685 if (isEqualOp) { 5686 for (BuiltinCandidateTypeSet::iterator 5687 Ptr = CandidateTypes[1].pointer_begin(), 5688 PtrEnd = CandidateTypes[1].pointer_end(); 5689 Ptr != PtrEnd; ++Ptr) { 5690 // Make sure we don't add the same candidate twice. 5691 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5692 continue; 5693 5694 QualType ParamTypes[2] = { 5695 S.Context.getLValueReferenceType(*Ptr), 5696 *Ptr, 5697 }; 5698 5699 // non-volatile version 5700 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5701 /*IsAssigmentOperator=*/true); 5702 5703 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5704 VisibleTypeConversionsQuals.hasVolatile()) { 5705 // volatile version 5706 ParamTypes[0] = 5707 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 5708 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5709 CandidateSet, /*IsAssigmentOperator=*/true); 5710 } 5711 } 5712 } 5713 } 5714 5715 // C++ [over.built]p18: 5716 // 5717 // For every triple (L, VQ, R), where L is an arithmetic type, 5718 // VQ is either volatile or empty, and R is a promoted 5719 // arithmetic type, there exist candidate operator functions of 5720 // the form 5721 // 5722 // VQ L& operator=(VQ L&, R); 5723 // VQ L& operator*=(VQ L&, R); 5724 // VQ L& operator/=(VQ L&, R); 5725 // VQ L& operator+=(VQ L&, R); 5726 // VQ L& operator-=(VQ L&, R); 5727 void addAssignmentArithmeticOverloads(bool isEqualOp) { 5728 if (!HasArithmeticOrEnumeralCandidateType) 5729 return; 5730 5731 for (unsigned Left = 0; Left < NumArithmeticTypes; ++Left) { 5732 for (unsigned Right = FirstPromotedArithmeticType; 5733 Right < LastPromotedArithmeticType; ++Right) { 5734 QualType ParamTypes[2]; 5735 ParamTypes[1] = getArithmeticType(Right); 5736 5737 // Add this built-in operator as a candidate (VQ is empty). 5738 ParamTypes[0] = 5739 S.Context.getLValueReferenceType(getArithmeticType(Left)); 5740 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5741 /*IsAssigmentOperator=*/isEqualOp); 5742 5743 // Add this built-in operator as a candidate (VQ is 'volatile'). 5744 if (VisibleTypeConversionsQuals.hasVolatile()) { 5745 ParamTypes[0] = 5746 S.Context.getVolatileType(getArithmeticType(Left)); 5747 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 5748 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5749 CandidateSet, 5750 /*IsAssigmentOperator=*/isEqualOp); 5751 } 5752 } 5753 } 5754 5755 // Extension: Add the binary operators =, +=, -=, *=, /= for vector types. 5756 for (BuiltinCandidateTypeSet::iterator 5757 Vec1 = CandidateTypes[0].vector_begin(), 5758 Vec1End = CandidateTypes[0].vector_end(); 5759 Vec1 != Vec1End; ++Vec1) { 5760 for (BuiltinCandidateTypeSet::iterator 5761 Vec2 = CandidateTypes[1].vector_begin(), 5762 Vec2End = CandidateTypes[1].vector_end(); 5763 Vec2 != Vec2End; ++Vec2) { 5764 QualType ParamTypes[2]; 5765 ParamTypes[1] = *Vec2; 5766 // Add this built-in operator as a candidate (VQ is empty). 5767 ParamTypes[0] = S.Context.getLValueReferenceType(*Vec1); 5768 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5769 /*IsAssigmentOperator=*/isEqualOp); 5770 5771 // Add this built-in operator as a candidate (VQ is 'volatile'). 5772 if (VisibleTypeConversionsQuals.hasVolatile()) { 5773 ParamTypes[0] = S.Context.getVolatileType(*Vec1); 5774 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 5775 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5776 CandidateSet, 5777 /*IsAssigmentOperator=*/isEqualOp); 5778 } 5779 } 5780 } 5781 } 5782 5783 // C++ [over.built]p22: 5784 // 5785 // For every triple (L, VQ, R), where L is an integral type, VQ 5786 // is either volatile or empty, and R is a promoted integral 5787 // type, there exist candidate operator functions of the form 5788 // 5789 // VQ L& operator%=(VQ L&, R); 5790 // VQ L& operator<<=(VQ L&, R); 5791 // VQ L& operator>>=(VQ L&, R); 5792 // VQ L& operator&=(VQ L&, R); 5793 // VQ L& operator^=(VQ L&, R); 5794 // VQ L& operator|=(VQ L&, R); 5795 void addAssignmentIntegralOverloads() { 5796 if (!HasArithmeticOrEnumeralCandidateType) 5797 return; 5798 5799 for (unsigned Left = FirstIntegralType; Left < LastIntegralType; ++Left) { 5800 for (unsigned Right = FirstPromotedIntegralType; 5801 Right < LastPromotedIntegralType; ++Right) { 5802 QualType ParamTypes[2]; 5803 ParamTypes[1] = getArithmeticType(Right); 5804 5805 // Add this built-in operator as a candidate (VQ is empty). 5806 ParamTypes[0] = 5807 S.Context.getLValueReferenceType(getArithmeticType(Left)); 5808 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet); 5809 if (VisibleTypeConversionsQuals.hasVolatile()) { 5810 // Add this built-in operator as a candidate (VQ is 'volatile'). 5811 ParamTypes[0] = getArithmeticType(Left); 5812 ParamTypes[0] = S.Context.getVolatileType(ParamTypes[0]); 5813 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 5814 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5815 CandidateSet); 5816 } 5817 } 5818 } 5819 } 5820 5821 // C++ [over.operator]p23: 5822 // 5823 // There also exist candidate operator functions of the form 5824 // 5825 // bool operator!(bool); 5826 // bool operator&&(bool, bool); 5827 // bool operator||(bool, bool); 5828 void addExclaimOverload() { 5829 QualType ParamTy = S.Context.BoolTy; 5830 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet, 5831 /*IsAssignmentOperator=*/false, 5832 /*NumContextualBoolArguments=*/1); 5833 } 5834 void addAmpAmpOrPipePipeOverload() { 5835 QualType ParamTypes[2] = { S.Context.BoolTy, S.Context.BoolTy }; 5836 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, CandidateSet, 5837 /*IsAssignmentOperator=*/false, 5838 /*NumContextualBoolArguments=*/2); 5839 } 5840 5841 // C++ [over.built]p13: 5842 // 5843 // For every cv-qualified or cv-unqualified object type T there 5844 // exist candidate operator functions of the form 5845 // 5846 // T* operator+(T*, ptrdiff_t); [ABOVE] 5847 // T& operator[](T*, ptrdiff_t); 5848 // T* operator-(T*, ptrdiff_t); [ABOVE] 5849 // T* operator+(ptrdiff_t, T*); [ABOVE] 5850 // T& operator[](ptrdiff_t, T*); 5851 void addSubscriptOverloads() { 5852 for (BuiltinCandidateTypeSet::iterator 5853 Ptr = CandidateTypes[0].pointer_begin(), 5854 PtrEnd = CandidateTypes[0].pointer_end(); 5855 Ptr != PtrEnd; ++Ptr) { 5856 QualType ParamTypes[2] = { *Ptr, S.Context.getPointerDiffType() }; 5857 QualType PointeeType = (*Ptr)->getPointeeType(); 5858 if (!PointeeType->isObjectType()) 5859 continue; 5860 5861 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 5862 5863 // T& operator[](T*, ptrdiff_t) 5864 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 5865 } 5866 5867 for (BuiltinCandidateTypeSet::iterator 5868 Ptr = CandidateTypes[1].pointer_begin(), 5869 PtrEnd = CandidateTypes[1].pointer_end(); 5870 Ptr != PtrEnd; ++Ptr) { 5871 QualType ParamTypes[2] = { S.Context.getPointerDiffType(), *Ptr }; 5872 QualType PointeeType = (*Ptr)->getPointeeType(); 5873 if (!PointeeType->isObjectType()) 5874 continue; 5875 5876 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 5877 5878 // T& operator[](ptrdiff_t, T*) 5879 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 5880 } 5881 } 5882 5883 // C++ [over.built]p11: 5884 // For every quintuple (C1, C2, T, CV1, CV2), where C2 is a class type, 5885 // C1 is the same type as C2 or is a derived class of C2, T is an object 5886 // type or a function type, and CV1 and CV2 are cv-qualifier-seqs, 5887 // there exist candidate operator functions of the form 5888 // 5889 // CV12 T& operator->*(CV1 C1*, CV2 T C2::*); 5890 // 5891 // where CV12 is the union of CV1 and CV2. 5892 void addArrowStarOverloads() { 5893 for (BuiltinCandidateTypeSet::iterator 5894 Ptr = CandidateTypes[0].pointer_begin(), 5895 PtrEnd = CandidateTypes[0].pointer_end(); 5896 Ptr != PtrEnd; ++Ptr) { 5897 QualType C1Ty = (*Ptr); 5898 QualType C1; 5899 QualifierCollector Q1; 5900 C1 = QualType(Q1.strip(C1Ty->getPointeeType()), 0); 5901 if (!isa<RecordType>(C1)) 5902 continue; 5903 // heuristic to reduce number of builtin candidates in the set. 5904 // Add volatile/restrict version only if there are conversions to a 5905 // volatile/restrict type. 5906 if (!VisibleTypeConversionsQuals.hasVolatile() && Q1.hasVolatile()) 5907 continue; 5908 if (!VisibleTypeConversionsQuals.hasRestrict() && Q1.hasRestrict()) 5909 continue; 5910 for (BuiltinCandidateTypeSet::iterator 5911 MemPtr = CandidateTypes[1].member_pointer_begin(), 5912 MemPtrEnd = CandidateTypes[1].member_pointer_end(); 5913 MemPtr != MemPtrEnd; ++MemPtr) { 5914 const MemberPointerType *mptr = cast<MemberPointerType>(*MemPtr); 5915 QualType C2 = QualType(mptr->getClass(), 0); 5916 C2 = C2.getUnqualifiedType(); 5917 if (C1 != C2 && !S.IsDerivedFrom(C1, C2)) 5918 break; 5919 QualType ParamTypes[2] = { *Ptr, *MemPtr }; 5920 // build CV12 T& 5921 QualType T = mptr->getPointeeType(); 5922 if (!VisibleTypeConversionsQuals.hasVolatile() && 5923 T.isVolatileQualified()) 5924 continue; 5925 if (!VisibleTypeConversionsQuals.hasRestrict() && 5926 T.isRestrictQualified()) 5927 continue; 5928 T = Q1.apply(S.Context, T); 5929 QualType ResultTy = S.Context.getLValueReferenceType(T); 5930 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 5931 } 5932 } 5933 } 5934 5935 // Note that we don't consider the first argument, since it has been 5936 // contextually converted to bool long ago. The candidates below are 5937 // therefore added as binary. 5938 // 5939 // C++ [over.built]p25: 5940 // For every type T, where T is a pointer, pointer-to-member, or scoped 5941 // enumeration type, there exist candidate operator functions of the form 5942 // 5943 // T operator?(bool, T, T); 5944 // 5945 void addConditionalOperatorOverloads() { 5946 /// Set of (canonical) types that we've already handled. 5947 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5948 5949 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 5950 for (BuiltinCandidateTypeSet::iterator 5951 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 5952 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 5953 Ptr != PtrEnd; ++Ptr) { 5954 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5955 continue; 5956 5957 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5958 S.AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 5959 } 5960 5961 for (BuiltinCandidateTypeSet::iterator 5962 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5963 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5964 MemPtr != MemPtrEnd; ++MemPtr) { 5965 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5966 continue; 5967 5968 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 5969 S.AddBuiltinCandidate(*MemPtr, ParamTypes, Args, 2, CandidateSet); 5970 } 5971 5972 if (S.getLangOptions().CPlusPlus0x) { 5973 for (BuiltinCandidateTypeSet::iterator 5974 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5975 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5976 Enum != EnumEnd; ++Enum) { 5977 if (!(*Enum)->getAs<EnumType>()->getDecl()->isScoped()) 5978 continue; 5979 5980 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 5981 continue; 5982 5983 QualType ParamTypes[2] = { *Enum, *Enum }; 5984 S.AddBuiltinCandidate(*Enum, ParamTypes, Args, 2, CandidateSet); 5985 } 5986 } 5987 } 5988 } 5989}; 5990 5991} // end anonymous namespace 5992 5993/// AddBuiltinOperatorCandidates - Add the appropriate built-in 5994/// operator overloads to the candidate set (C++ [over.built]), based 5995/// on the operator @p Op and the arguments given. For example, if the 5996/// operator is a binary '+', this routine might add "int 5997/// operator+(int, int)" to cover integer addition. 5998void 5999Sema::AddBuiltinOperatorCandidates(OverloadedOperatorKind Op, 6000 SourceLocation OpLoc, 6001 Expr **Args, unsigned NumArgs, 6002 OverloadCandidateSet& CandidateSet) { 6003 // Find all of the types that the arguments can convert to, but only 6004 // if the operator we're looking at has built-in operator candidates 6005 // that make use of these types. Also record whether we encounter non-record 6006 // candidate types or either arithmetic or enumeral candidate types. 6007 Qualifiers VisibleTypeConversionsQuals; 6008 VisibleTypeConversionsQuals.addConst(); 6009 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 6010 VisibleTypeConversionsQuals += CollectVRQualifiers(Context, Args[ArgIdx]); 6011 6012 bool HasNonRecordCandidateType = false; 6013 bool HasArithmeticOrEnumeralCandidateType = false; 6014 llvm::SmallVector<BuiltinCandidateTypeSet, 2> CandidateTypes; 6015 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6016 CandidateTypes.push_back(BuiltinCandidateTypeSet(*this)); 6017 CandidateTypes[ArgIdx].AddTypesConvertedFrom(Args[ArgIdx]->getType(), 6018 OpLoc, 6019 true, 6020 (Op == OO_Exclaim || 6021 Op == OO_AmpAmp || 6022 Op == OO_PipePipe), 6023 VisibleTypeConversionsQuals); 6024 HasNonRecordCandidateType = HasNonRecordCandidateType || 6025 CandidateTypes[ArgIdx].hasNonRecordTypes(); 6026 HasArithmeticOrEnumeralCandidateType = 6027 HasArithmeticOrEnumeralCandidateType || 6028 CandidateTypes[ArgIdx].hasArithmeticOrEnumeralTypes(); 6029 } 6030 6031 // Exit early when no non-record types have been added to the candidate set 6032 // for any of the arguments to the operator. 6033 if (!HasNonRecordCandidateType) 6034 return; 6035 6036 // Setup an object to manage the common state for building overloads. 6037 BuiltinOperatorOverloadBuilder OpBuilder(*this, Args, NumArgs, 6038 VisibleTypeConversionsQuals, 6039 HasArithmeticOrEnumeralCandidateType, 6040 CandidateTypes, CandidateSet); 6041 6042 // Dispatch over the operation to add in only those overloads which apply. 6043 switch (Op) { 6044 case OO_None: 6045 case NUM_OVERLOADED_OPERATORS: 6046 assert(false && "Expected an overloaded operator"); 6047 break; 6048 6049 case OO_New: 6050 case OO_Delete: 6051 case OO_Array_New: 6052 case OO_Array_Delete: 6053 case OO_Call: 6054 assert(false && "Special operators don't use AddBuiltinOperatorCandidates"); 6055 break; 6056 6057 case OO_Comma: 6058 case OO_Arrow: 6059 // C++ [over.match.oper]p3: 6060 // -- For the operator ',', the unary operator '&', or the 6061 // operator '->', the built-in candidates set is empty. 6062 break; 6063 6064 case OO_Plus: // '+' is either unary or binary 6065 if (NumArgs == 1) 6066 OpBuilder.addUnaryPlusPointerOverloads(); 6067 // Fall through. 6068 6069 case OO_Minus: // '-' is either unary or binary 6070 if (NumArgs == 1) { 6071 OpBuilder.addUnaryPlusOrMinusArithmeticOverloads(); 6072 } else { 6073 OpBuilder.addBinaryPlusOrMinusPointerOverloads(Op); 6074 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6075 } 6076 break; 6077 6078 case OO_Star: // '*' is either unary or binary 6079 if (NumArgs == 1) 6080 OpBuilder.addUnaryStarPointerOverloads(); 6081 else 6082 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6083 break; 6084 6085 case OO_Slash: 6086 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6087 break; 6088 6089 case OO_PlusPlus: 6090 case OO_MinusMinus: 6091 OpBuilder.addPlusPlusMinusMinusArithmeticOverloads(Op); 6092 OpBuilder.addPlusPlusMinusMinusPointerOverloads(); 6093 break; 6094 6095 case OO_EqualEqual: 6096 case OO_ExclaimEqual: 6097 OpBuilder.addEqualEqualOrNotEqualMemberPointerOverloads(); 6098 // Fall through. 6099 6100 case OO_Less: 6101 case OO_Greater: 6102 case OO_LessEqual: 6103 case OO_GreaterEqual: 6104 OpBuilder.addRelationalPointerOrEnumeralOverloads(); 6105 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/true); 6106 break; 6107 6108 case OO_Percent: 6109 case OO_Caret: 6110 case OO_Pipe: 6111 case OO_LessLess: 6112 case OO_GreaterGreater: 6113 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6114 break; 6115 6116 case OO_Amp: // '&' is either unary or binary 6117 if (NumArgs == 1) 6118 // C++ [over.match.oper]p3: 6119 // -- For the operator ',', the unary operator '&', or the 6120 // operator '->', the built-in candidates set is empty. 6121 break; 6122 6123 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6124 break; 6125 6126 case OO_Tilde: 6127 OpBuilder.addUnaryTildePromotedIntegralOverloads(); 6128 break; 6129 6130 case OO_Equal: 6131 OpBuilder.addAssignmentMemberPointerOrEnumeralOverloads(); 6132 // Fall through. 6133 6134 case OO_PlusEqual: 6135 case OO_MinusEqual: 6136 OpBuilder.addAssignmentPointerOverloads(Op == OO_Equal); 6137 // Fall through. 6138 6139 case OO_StarEqual: 6140 case OO_SlashEqual: 6141 OpBuilder.addAssignmentArithmeticOverloads(Op == OO_Equal); 6142 break; 6143 6144 case OO_PercentEqual: 6145 case OO_LessLessEqual: 6146 case OO_GreaterGreaterEqual: 6147 case OO_AmpEqual: 6148 case OO_CaretEqual: 6149 case OO_PipeEqual: 6150 OpBuilder.addAssignmentIntegralOverloads(); 6151 break; 6152 6153 case OO_Exclaim: 6154 OpBuilder.addExclaimOverload(); 6155 break; 6156 6157 case OO_AmpAmp: 6158 case OO_PipePipe: 6159 OpBuilder.addAmpAmpOrPipePipeOverload(); 6160 break; 6161 6162 case OO_Subscript: 6163 OpBuilder.addSubscriptOverloads(); 6164 break; 6165 6166 case OO_ArrowStar: 6167 OpBuilder.addArrowStarOverloads(); 6168 break; 6169 6170 case OO_Conditional: 6171 OpBuilder.addConditionalOperatorOverloads(); 6172 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6173 break; 6174 } 6175} 6176 6177/// \brief Add function candidates found via argument-dependent lookup 6178/// to the set of overloading candidates. 6179/// 6180/// This routine performs argument-dependent name lookup based on the 6181/// given function name (which may also be an operator name) and adds 6182/// all of the overload candidates found by ADL to the overload 6183/// candidate set (C++ [basic.lookup.argdep]). 6184void 6185Sema::AddArgumentDependentLookupCandidates(DeclarationName Name, 6186 bool Operator, 6187 Expr **Args, unsigned NumArgs, 6188 TemplateArgumentListInfo *ExplicitTemplateArgs, 6189 OverloadCandidateSet& CandidateSet, 6190 bool PartialOverloading, 6191 bool StdNamespaceIsAssociated) { 6192 ADLResult Fns; 6193 6194 // FIXME: This approach for uniquing ADL results (and removing 6195 // redundant candidates from the set) relies on pointer-equality, 6196 // which means we need to key off the canonical decl. However, 6197 // always going back to the canonical decl might not get us the 6198 // right set of default arguments. What default arguments are 6199 // we supposed to consider on ADL candidates, anyway? 6200 6201 // FIXME: Pass in the explicit template arguments? 6202 ArgumentDependentLookup(Name, Operator, Args, NumArgs, Fns, 6203 StdNamespaceIsAssociated); 6204 6205 // Erase all of the candidates we already knew about. 6206 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(), 6207 CandEnd = CandidateSet.end(); 6208 Cand != CandEnd; ++Cand) 6209 if (Cand->Function) { 6210 Fns.erase(Cand->Function); 6211 if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate()) 6212 Fns.erase(FunTmpl); 6213 } 6214 6215 // For each of the ADL candidates we found, add it to the overload 6216 // set. 6217 for (ADLResult::iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) { 6218 DeclAccessPair FoundDecl = DeclAccessPair::make(*I, AS_none); 6219 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) { 6220 if (ExplicitTemplateArgs) 6221 continue; 6222 6223 AddOverloadCandidate(FD, FoundDecl, Args, NumArgs, CandidateSet, 6224 false, PartialOverloading); 6225 } else 6226 AddTemplateOverloadCandidate(cast<FunctionTemplateDecl>(*I), 6227 FoundDecl, ExplicitTemplateArgs, 6228 Args, NumArgs, CandidateSet); 6229 } 6230} 6231 6232/// isBetterOverloadCandidate - Determines whether the first overload 6233/// candidate is a better candidate than the second (C++ 13.3.3p1). 6234bool 6235isBetterOverloadCandidate(Sema &S, 6236 const OverloadCandidate &Cand1, 6237 const OverloadCandidate &Cand2, 6238 SourceLocation Loc, 6239 bool UserDefinedConversion) { 6240 // Define viable functions to be better candidates than non-viable 6241 // functions. 6242 if (!Cand2.Viable) 6243 return Cand1.Viable; 6244 else if (!Cand1.Viable) 6245 return false; 6246 6247 // C++ [over.match.best]p1: 6248 // 6249 // -- if F is a static member function, ICS1(F) is defined such 6250 // that ICS1(F) is neither better nor worse than ICS1(G) for 6251 // any function G, and, symmetrically, ICS1(G) is neither 6252 // better nor worse than ICS1(F). 6253 unsigned StartArg = 0; 6254 if (Cand1.IgnoreObjectArgument || Cand2.IgnoreObjectArgument) 6255 StartArg = 1; 6256 6257 // C++ [over.match.best]p1: 6258 // A viable function F1 is defined to be a better function than another 6259 // viable function F2 if for all arguments i, ICSi(F1) is not a worse 6260 // conversion sequence than ICSi(F2), and then... 6261 unsigned NumArgs = Cand1.Conversions.size(); 6262 assert(Cand2.Conversions.size() == NumArgs && "Overload candidate mismatch"); 6263 bool HasBetterConversion = false; 6264 for (unsigned ArgIdx = StartArg; ArgIdx < NumArgs; ++ArgIdx) { 6265 switch (CompareImplicitConversionSequences(S, 6266 Cand1.Conversions[ArgIdx], 6267 Cand2.Conversions[ArgIdx])) { 6268 case ImplicitConversionSequence::Better: 6269 // Cand1 has a better conversion sequence. 6270 HasBetterConversion = true; 6271 break; 6272 6273 case ImplicitConversionSequence::Worse: 6274 // Cand1 can't be better than Cand2. 6275 return false; 6276 6277 case ImplicitConversionSequence::Indistinguishable: 6278 // Do nothing. 6279 break; 6280 } 6281 } 6282 6283 // -- for some argument j, ICSj(F1) is a better conversion sequence than 6284 // ICSj(F2), or, if not that, 6285 if (HasBetterConversion) 6286 return true; 6287 6288 // - F1 is a non-template function and F2 is a function template 6289 // specialization, or, if not that, 6290 if ((!Cand1.Function || !Cand1.Function->getPrimaryTemplate()) && 6291 Cand2.Function && Cand2.Function->getPrimaryTemplate()) 6292 return true; 6293 6294 // -- F1 and F2 are function template specializations, and the function 6295 // template for F1 is more specialized than the template for F2 6296 // according to the partial ordering rules described in 14.5.5.2, or, 6297 // if not that, 6298 if (Cand1.Function && Cand1.Function->getPrimaryTemplate() && 6299 Cand2.Function && Cand2.Function->getPrimaryTemplate()) { 6300 if (FunctionTemplateDecl *BetterTemplate 6301 = S.getMoreSpecializedTemplate(Cand1.Function->getPrimaryTemplate(), 6302 Cand2.Function->getPrimaryTemplate(), 6303 Loc, 6304 isa<CXXConversionDecl>(Cand1.Function)? TPOC_Conversion 6305 : TPOC_Call, 6306 Cand1.ExplicitCallArguments)) 6307 return BetterTemplate == Cand1.Function->getPrimaryTemplate(); 6308 } 6309 6310 // -- the context is an initialization by user-defined conversion 6311 // (see 8.5, 13.3.1.5) and the standard conversion sequence 6312 // from the return type of F1 to the destination type (i.e., 6313 // the type of the entity being initialized) is a better 6314 // conversion sequence than the standard conversion sequence 6315 // from the return type of F2 to the destination type. 6316 if (UserDefinedConversion && Cand1.Function && Cand2.Function && 6317 isa<CXXConversionDecl>(Cand1.Function) && 6318 isa<CXXConversionDecl>(Cand2.Function)) { 6319 switch (CompareStandardConversionSequences(S, 6320 Cand1.FinalConversion, 6321 Cand2.FinalConversion)) { 6322 case ImplicitConversionSequence::Better: 6323 // Cand1 has a better conversion sequence. 6324 return true; 6325 6326 case ImplicitConversionSequence::Worse: 6327 // Cand1 can't be better than Cand2. 6328 return false; 6329 6330 case ImplicitConversionSequence::Indistinguishable: 6331 // Do nothing 6332 break; 6333 } 6334 } 6335 6336 return false; 6337} 6338 6339/// \brief Computes the best viable function (C++ 13.3.3) 6340/// within an overload candidate set. 6341/// 6342/// \param CandidateSet the set of candidate functions. 6343/// 6344/// \param Loc the location of the function name (or operator symbol) for 6345/// which overload resolution occurs. 6346/// 6347/// \param Best f overload resolution was successful or found a deleted 6348/// function, Best points to the candidate function found. 6349/// 6350/// \returns The result of overload resolution. 6351OverloadingResult 6352OverloadCandidateSet::BestViableFunction(Sema &S, SourceLocation Loc, 6353 iterator &Best, 6354 bool UserDefinedConversion) { 6355 // Find the best viable function. 6356 Best = end(); 6357 for (iterator Cand = begin(); Cand != end(); ++Cand) { 6358 if (Cand->Viable) 6359 if (Best == end() || isBetterOverloadCandidate(S, *Cand, *Best, Loc, 6360 UserDefinedConversion)) 6361 Best = Cand; 6362 } 6363 6364 // If we didn't find any viable functions, abort. 6365 if (Best == end()) 6366 return OR_No_Viable_Function; 6367 6368 // Make sure that this function is better than every other viable 6369 // function. If not, we have an ambiguity. 6370 for (iterator Cand = begin(); Cand != end(); ++Cand) { 6371 if (Cand->Viable && 6372 Cand != Best && 6373 !isBetterOverloadCandidate(S, *Best, *Cand, Loc, 6374 UserDefinedConversion)) { 6375 Best = end(); 6376 return OR_Ambiguous; 6377 } 6378 } 6379 6380 // Best is the best viable function. 6381 if (Best->Function && 6382 (Best->Function->isDeleted() || Best->Function->isUnavailable())) 6383 return OR_Deleted; 6384 6385 return OR_Success; 6386} 6387 6388namespace { 6389 6390enum OverloadCandidateKind { 6391 oc_function, 6392 oc_method, 6393 oc_constructor, 6394 oc_function_template, 6395 oc_method_template, 6396 oc_constructor_template, 6397 oc_implicit_default_constructor, 6398 oc_implicit_copy_constructor, 6399 oc_implicit_copy_assignment, 6400 oc_implicit_inherited_constructor 6401}; 6402 6403OverloadCandidateKind ClassifyOverloadCandidate(Sema &S, 6404 FunctionDecl *Fn, 6405 std::string &Description) { 6406 bool isTemplate = false; 6407 6408 if (FunctionTemplateDecl *FunTmpl = Fn->getPrimaryTemplate()) { 6409 isTemplate = true; 6410 Description = S.getTemplateArgumentBindingsText( 6411 FunTmpl->getTemplateParameters(), *Fn->getTemplateSpecializationArgs()); 6412 } 6413 6414 if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn)) { 6415 if (!Ctor->isImplicit()) 6416 return isTemplate ? oc_constructor_template : oc_constructor; 6417 6418 if (Ctor->getInheritedConstructor()) 6419 return oc_implicit_inherited_constructor; 6420 6421 return Ctor->isCopyConstructor() ? oc_implicit_copy_constructor 6422 : oc_implicit_default_constructor; 6423 } 6424 6425 if (CXXMethodDecl *Meth = dyn_cast<CXXMethodDecl>(Fn)) { 6426 // This actually gets spelled 'candidate function' for now, but 6427 // it doesn't hurt to split it out. 6428 if (!Meth->isImplicit()) 6429 return isTemplate ? oc_method_template : oc_method; 6430 6431 assert(Meth->isCopyAssignmentOperator() 6432 && "implicit method is not copy assignment operator?"); 6433 return oc_implicit_copy_assignment; 6434 } 6435 6436 return isTemplate ? oc_function_template : oc_function; 6437} 6438 6439void MaybeEmitInheritedConstructorNote(Sema &S, FunctionDecl *Fn) { 6440 const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn); 6441 if (!Ctor) return; 6442 6443 Ctor = Ctor->getInheritedConstructor(); 6444 if (!Ctor) return; 6445 6446 S.Diag(Ctor->getLocation(), diag::note_ovl_candidate_inherited_constructor); 6447} 6448 6449} // end anonymous namespace 6450 6451// Notes the location of an overload candidate. 6452void Sema::NoteOverloadCandidate(FunctionDecl *Fn) { 6453 std::string FnDesc; 6454 OverloadCandidateKind K = ClassifyOverloadCandidate(*this, Fn, FnDesc); 6455 Diag(Fn->getLocation(), diag::note_ovl_candidate) 6456 << (unsigned) K << FnDesc; 6457 MaybeEmitInheritedConstructorNote(*this, Fn); 6458} 6459 6460//Notes the location of all overload candidates designated through 6461// OverloadedExpr 6462void Sema::NoteAllOverloadCandidates(Expr* OverloadedExpr) { 6463 assert(OverloadedExpr->getType() == Context.OverloadTy); 6464 6465 OverloadExpr::FindResult Ovl = OverloadExpr::find(OverloadedExpr); 6466 OverloadExpr *OvlExpr = Ovl.Expression; 6467 6468 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 6469 IEnd = OvlExpr->decls_end(); 6470 I != IEnd; ++I) { 6471 if (FunctionTemplateDecl *FunTmpl = 6472 dyn_cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()) ) { 6473 NoteOverloadCandidate(FunTmpl->getTemplatedDecl()); 6474 } else if (FunctionDecl *Fun 6475 = dyn_cast<FunctionDecl>((*I)->getUnderlyingDecl()) ) { 6476 NoteOverloadCandidate(Fun); 6477 } 6478 } 6479} 6480 6481/// Diagnoses an ambiguous conversion. The partial diagnostic is the 6482/// "lead" diagnostic; it will be given two arguments, the source and 6483/// target types of the conversion. 6484void ImplicitConversionSequence::DiagnoseAmbiguousConversion( 6485 Sema &S, 6486 SourceLocation CaretLoc, 6487 const PartialDiagnostic &PDiag) const { 6488 S.Diag(CaretLoc, PDiag) 6489 << Ambiguous.getFromType() << Ambiguous.getToType(); 6490 for (AmbiguousConversionSequence::const_iterator 6491 I = Ambiguous.begin(), E = Ambiguous.end(); I != E; ++I) { 6492 S.NoteOverloadCandidate(*I); 6493 } 6494} 6495 6496namespace { 6497 6498void DiagnoseBadConversion(Sema &S, OverloadCandidate *Cand, unsigned I) { 6499 const ImplicitConversionSequence &Conv = Cand->Conversions[I]; 6500 assert(Conv.isBad()); 6501 assert(Cand->Function && "for now, candidate must be a function"); 6502 FunctionDecl *Fn = Cand->Function; 6503 6504 // There's a conversion slot for the object argument if this is a 6505 // non-constructor method. Note that 'I' corresponds the 6506 // conversion-slot index. 6507 bool isObjectArgument = false; 6508 if (isa<CXXMethodDecl>(Fn) && !isa<CXXConstructorDecl>(Fn)) { 6509 if (I == 0) 6510 isObjectArgument = true; 6511 else 6512 I--; 6513 } 6514 6515 std::string FnDesc; 6516 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 6517 6518 Expr *FromExpr = Conv.Bad.FromExpr; 6519 QualType FromTy = Conv.Bad.getFromType(); 6520 QualType ToTy = Conv.Bad.getToType(); 6521 6522 if (FromTy == S.Context.OverloadTy) { 6523 assert(FromExpr && "overload set argument came from implicit argument?"); 6524 Expr *E = FromExpr->IgnoreParens(); 6525 if (isa<UnaryOperator>(E)) 6526 E = cast<UnaryOperator>(E)->getSubExpr()->IgnoreParens(); 6527 DeclarationName Name = cast<OverloadExpr>(E)->getName(); 6528 6529 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_overload) 6530 << (unsigned) FnKind << FnDesc 6531 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6532 << ToTy << Name << I+1; 6533 MaybeEmitInheritedConstructorNote(S, Fn); 6534 return; 6535 } 6536 6537 // Do some hand-waving analysis to see if the non-viability is due 6538 // to a qualifier mismatch. 6539 CanQualType CFromTy = S.Context.getCanonicalType(FromTy); 6540 CanQualType CToTy = S.Context.getCanonicalType(ToTy); 6541 if (CanQual<ReferenceType> RT = CToTy->getAs<ReferenceType>()) 6542 CToTy = RT->getPointeeType(); 6543 else { 6544 // TODO: detect and diagnose the full richness of const mismatches. 6545 if (CanQual<PointerType> FromPT = CFromTy->getAs<PointerType>()) 6546 if (CanQual<PointerType> ToPT = CToTy->getAs<PointerType>()) 6547 CFromTy = FromPT->getPointeeType(), CToTy = ToPT->getPointeeType(); 6548 } 6549 6550 if (CToTy.getUnqualifiedType() == CFromTy.getUnqualifiedType() && 6551 !CToTy.isAtLeastAsQualifiedAs(CFromTy)) { 6552 // It is dumb that we have to do this here. 6553 while (isa<ArrayType>(CFromTy)) 6554 CFromTy = CFromTy->getAs<ArrayType>()->getElementType(); 6555 while (isa<ArrayType>(CToTy)) 6556 CToTy = CFromTy->getAs<ArrayType>()->getElementType(); 6557 6558 Qualifiers FromQs = CFromTy.getQualifiers(); 6559 Qualifiers ToQs = CToTy.getQualifiers(); 6560 6561 if (FromQs.getAddressSpace() != ToQs.getAddressSpace()) { 6562 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_addrspace) 6563 << (unsigned) FnKind << FnDesc 6564 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6565 << FromTy 6566 << FromQs.getAddressSpace() << ToQs.getAddressSpace() 6567 << (unsigned) isObjectArgument << I+1; 6568 MaybeEmitInheritedConstructorNote(S, Fn); 6569 return; 6570 } 6571 6572 if (FromQs.getObjCGCAttr() != ToQs.getObjCGCAttr()) { 6573 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_gc) 6574 << (unsigned) FnKind << FnDesc 6575 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6576 << FromTy 6577 << FromQs.getObjCGCAttr() << ToQs.getObjCGCAttr() 6578 << (unsigned) isObjectArgument << I+1; 6579 MaybeEmitInheritedConstructorNote(S, Fn); 6580 return; 6581 } 6582 6583 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 6584 assert(CVR && "unexpected qualifiers mismatch"); 6585 6586 if (isObjectArgument) { 6587 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr_this) 6588 << (unsigned) FnKind << FnDesc 6589 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6590 << FromTy << (CVR - 1); 6591 } else { 6592 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr) 6593 << (unsigned) FnKind << FnDesc 6594 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6595 << FromTy << (CVR - 1) << I+1; 6596 } 6597 MaybeEmitInheritedConstructorNote(S, Fn); 6598 return; 6599 } 6600 6601 // Diagnose references or pointers to incomplete types differently, 6602 // since it's far from impossible that the incompleteness triggered 6603 // the failure. 6604 QualType TempFromTy = FromTy.getNonReferenceType(); 6605 if (const PointerType *PTy = TempFromTy->getAs<PointerType>()) 6606 TempFromTy = PTy->getPointeeType(); 6607 if (TempFromTy->isIncompleteType()) { 6608 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv_incomplete) 6609 << (unsigned) FnKind << FnDesc 6610 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6611 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 6612 MaybeEmitInheritedConstructorNote(S, Fn); 6613 return; 6614 } 6615 6616 // Diagnose base -> derived pointer conversions. 6617 unsigned BaseToDerivedConversion = 0; 6618 if (const PointerType *FromPtrTy = FromTy->getAs<PointerType>()) { 6619 if (const PointerType *ToPtrTy = ToTy->getAs<PointerType>()) { 6620 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 6621 FromPtrTy->getPointeeType()) && 6622 !FromPtrTy->getPointeeType()->isIncompleteType() && 6623 !ToPtrTy->getPointeeType()->isIncompleteType() && 6624 S.IsDerivedFrom(ToPtrTy->getPointeeType(), 6625 FromPtrTy->getPointeeType())) 6626 BaseToDerivedConversion = 1; 6627 } 6628 } else if (const ObjCObjectPointerType *FromPtrTy 6629 = FromTy->getAs<ObjCObjectPointerType>()) { 6630 if (const ObjCObjectPointerType *ToPtrTy 6631 = ToTy->getAs<ObjCObjectPointerType>()) 6632 if (const ObjCInterfaceDecl *FromIface = FromPtrTy->getInterfaceDecl()) 6633 if (const ObjCInterfaceDecl *ToIface = ToPtrTy->getInterfaceDecl()) 6634 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 6635 FromPtrTy->getPointeeType()) && 6636 FromIface->isSuperClassOf(ToIface)) 6637 BaseToDerivedConversion = 2; 6638 } else if (const ReferenceType *ToRefTy = ToTy->getAs<ReferenceType>()) { 6639 if (ToRefTy->getPointeeType().isAtLeastAsQualifiedAs(FromTy) && 6640 !FromTy->isIncompleteType() && 6641 !ToRefTy->getPointeeType()->isIncompleteType() && 6642 S.IsDerivedFrom(ToRefTy->getPointeeType(), FromTy)) 6643 BaseToDerivedConversion = 3; 6644 } 6645 6646 if (BaseToDerivedConversion) { 6647 S.Diag(Fn->getLocation(), 6648 diag::note_ovl_candidate_bad_base_to_derived_conv) 6649 << (unsigned) FnKind << FnDesc 6650 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6651 << (BaseToDerivedConversion - 1) 6652 << FromTy << ToTy << I+1; 6653 MaybeEmitInheritedConstructorNote(S, Fn); 6654 return; 6655 } 6656 6657 // TODO: specialize more based on the kind of mismatch 6658 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv) 6659 << (unsigned) FnKind << FnDesc 6660 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6661 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 6662 MaybeEmitInheritedConstructorNote(S, Fn); 6663} 6664 6665void DiagnoseArityMismatch(Sema &S, OverloadCandidate *Cand, 6666 unsigned NumFormalArgs) { 6667 // TODO: treat calls to a missing default constructor as a special case 6668 6669 FunctionDecl *Fn = Cand->Function; 6670 const FunctionProtoType *FnTy = Fn->getType()->getAs<FunctionProtoType>(); 6671 6672 unsigned MinParams = Fn->getMinRequiredArguments(); 6673 6674 // at least / at most / exactly 6675 unsigned mode, modeCount; 6676 if (NumFormalArgs < MinParams) { 6677 assert((Cand->FailureKind == ovl_fail_too_few_arguments) || 6678 (Cand->FailureKind == ovl_fail_bad_deduction && 6679 Cand->DeductionFailure.Result == Sema::TDK_TooFewArguments)); 6680 if (MinParams != FnTy->getNumArgs() || 6681 FnTy->isVariadic() || FnTy->isTemplateVariadic()) 6682 mode = 0; // "at least" 6683 else 6684 mode = 2; // "exactly" 6685 modeCount = MinParams; 6686 } else { 6687 assert((Cand->FailureKind == ovl_fail_too_many_arguments) || 6688 (Cand->FailureKind == ovl_fail_bad_deduction && 6689 Cand->DeductionFailure.Result == Sema::TDK_TooManyArguments)); 6690 if (MinParams != FnTy->getNumArgs()) 6691 mode = 1; // "at most" 6692 else 6693 mode = 2; // "exactly" 6694 modeCount = FnTy->getNumArgs(); 6695 } 6696 6697 std::string Description; 6698 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, Description); 6699 6700 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity) 6701 << (unsigned) FnKind << (Fn->getDescribedFunctionTemplate() != 0) << mode 6702 << modeCount << NumFormalArgs; 6703 MaybeEmitInheritedConstructorNote(S, Fn); 6704} 6705 6706/// Diagnose a failed template-argument deduction. 6707void DiagnoseBadDeduction(Sema &S, OverloadCandidate *Cand, 6708 Expr **Args, unsigned NumArgs) { 6709 FunctionDecl *Fn = Cand->Function; // pattern 6710 6711 TemplateParameter Param = Cand->DeductionFailure.getTemplateParameter(); 6712 NamedDecl *ParamD; 6713 (ParamD = Param.dyn_cast<TemplateTypeParmDecl*>()) || 6714 (ParamD = Param.dyn_cast<NonTypeTemplateParmDecl*>()) || 6715 (ParamD = Param.dyn_cast<TemplateTemplateParmDecl*>()); 6716 switch (Cand->DeductionFailure.Result) { 6717 case Sema::TDK_Success: 6718 llvm_unreachable("TDK_success while diagnosing bad deduction"); 6719 6720 case Sema::TDK_Incomplete: { 6721 assert(ParamD && "no parameter found for incomplete deduction result"); 6722 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_incomplete_deduction) 6723 << ParamD->getDeclName(); 6724 MaybeEmitInheritedConstructorNote(S, Fn); 6725 return; 6726 } 6727 6728 case Sema::TDK_Underqualified: { 6729 assert(ParamD && "no parameter found for bad qualifiers deduction result"); 6730 TemplateTypeParmDecl *TParam = cast<TemplateTypeParmDecl>(ParamD); 6731 6732 QualType Param = Cand->DeductionFailure.getFirstArg()->getAsType(); 6733 6734 // Param will have been canonicalized, but it should just be a 6735 // qualified version of ParamD, so move the qualifiers to that. 6736 QualifierCollector Qs; 6737 Qs.strip(Param); 6738 QualType NonCanonParam = Qs.apply(S.Context, TParam->getTypeForDecl()); 6739 assert(S.Context.hasSameType(Param, NonCanonParam)); 6740 6741 // Arg has also been canonicalized, but there's nothing we can do 6742 // about that. It also doesn't matter as much, because it won't 6743 // have any template parameters in it (because deduction isn't 6744 // done on dependent types). 6745 QualType Arg = Cand->DeductionFailure.getSecondArg()->getAsType(); 6746 6747 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_underqualified) 6748 << ParamD->getDeclName() << Arg << NonCanonParam; 6749 MaybeEmitInheritedConstructorNote(S, Fn); 6750 return; 6751 } 6752 6753 case Sema::TDK_Inconsistent: { 6754 assert(ParamD && "no parameter found for inconsistent deduction result"); 6755 int which = 0; 6756 if (isa<TemplateTypeParmDecl>(ParamD)) 6757 which = 0; 6758 else if (isa<NonTypeTemplateParmDecl>(ParamD)) 6759 which = 1; 6760 else { 6761 which = 2; 6762 } 6763 6764 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_inconsistent_deduction) 6765 << which << ParamD->getDeclName() 6766 << *Cand->DeductionFailure.getFirstArg() 6767 << *Cand->DeductionFailure.getSecondArg(); 6768 MaybeEmitInheritedConstructorNote(S, Fn); 6769 return; 6770 } 6771 6772 case Sema::TDK_InvalidExplicitArguments: 6773 assert(ParamD && "no parameter found for invalid explicit arguments"); 6774 if (ParamD->getDeclName()) 6775 S.Diag(Fn->getLocation(), 6776 diag::note_ovl_candidate_explicit_arg_mismatch_named) 6777 << ParamD->getDeclName(); 6778 else { 6779 int index = 0; 6780 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ParamD)) 6781 index = TTP->getIndex(); 6782 else if (NonTypeTemplateParmDecl *NTTP 6783 = dyn_cast<NonTypeTemplateParmDecl>(ParamD)) 6784 index = NTTP->getIndex(); 6785 else 6786 index = cast<TemplateTemplateParmDecl>(ParamD)->getIndex(); 6787 S.Diag(Fn->getLocation(), 6788 diag::note_ovl_candidate_explicit_arg_mismatch_unnamed) 6789 << (index + 1); 6790 } 6791 MaybeEmitInheritedConstructorNote(S, Fn); 6792 return; 6793 6794 case Sema::TDK_TooManyArguments: 6795 case Sema::TDK_TooFewArguments: 6796 DiagnoseArityMismatch(S, Cand, NumArgs); 6797 return; 6798 6799 case Sema::TDK_InstantiationDepth: 6800 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_instantiation_depth); 6801 MaybeEmitInheritedConstructorNote(S, Fn); 6802 return; 6803 6804 case Sema::TDK_SubstitutionFailure: { 6805 std::string ArgString; 6806 if (TemplateArgumentList *Args 6807 = Cand->DeductionFailure.getTemplateArgumentList()) 6808 ArgString = S.getTemplateArgumentBindingsText( 6809 Fn->getDescribedFunctionTemplate()->getTemplateParameters(), 6810 *Args); 6811 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_substitution_failure) 6812 << ArgString; 6813 MaybeEmitInheritedConstructorNote(S, Fn); 6814 return; 6815 } 6816 6817 // TODO: diagnose these individually, then kill off 6818 // note_ovl_candidate_bad_deduction, which is uselessly vague. 6819 case Sema::TDK_NonDeducedMismatch: 6820 case Sema::TDK_FailedOverloadResolution: 6821 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_deduction); 6822 MaybeEmitInheritedConstructorNote(S, Fn); 6823 return; 6824 } 6825} 6826 6827/// Generates a 'note' diagnostic for an overload candidate. We've 6828/// already generated a primary error at the call site. 6829/// 6830/// It really does need to be a single diagnostic with its caret 6831/// pointed at the candidate declaration. Yes, this creates some 6832/// major challenges of technical writing. Yes, this makes pointing 6833/// out problems with specific arguments quite awkward. It's still 6834/// better than generating twenty screens of text for every failed 6835/// overload. 6836/// 6837/// It would be great to be able to express per-candidate problems 6838/// more richly for those diagnostic clients that cared, but we'd 6839/// still have to be just as careful with the default diagnostics. 6840void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand, 6841 Expr **Args, unsigned NumArgs) { 6842 FunctionDecl *Fn = Cand->Function; 6843 6844 // Note deleted candidates, but only if they're viable. 6845 if (Cand->Viable && (Fn->isDeleted() || Fn->isUnavailable())) { 6846 std::string FnDesc; 6847 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 6848 6849 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_deleted) 6850 << FnKind << FnDesc << Fn->isDeleted(); 6851 MaybeEmitInheritedConstructorNote(S, Fn); 6852 return; 6853 } 6854 6855 // We don't really have anything else to say about viable candidates. 6856 if (Cand->Viable) { 6857 S.NoteOverloadCandidate(Fn); 6858 return; 6859 } 6860 6861 switch (Cand->FailureKind) { 6862 case ovl_fail_too_many_arguments: 6863 case ovl_fail_too_few_arguments: 6864 return DiagnoseArityMismatch(S, Cand, NumArgs); 6865 6866 case ovl_fail_bad_deduction: 6867 return DiagnoseBadDeduction(S, Cand, Args, NumArgs); 6868 6869 case ovl_fail_trivial_conversion: 6870 case ovl_fail_bad_final_conversion: 6871 case ovl_fail_final_conversion_not_exact: 6872 return S.NoteOverloadCandidate(Fn); 6873 6874 case ovl_fail_bad_conversion: { 6875 unsigned I = (Cand->IgnoreObjectArgument ? 1 : 0); 6876 for (unsigned N = Cand->Conversions.size(); I != N; ++I) 6877 if (Cand->Conversions[I].isBad()) 6878 return DiagnoseBadConversion(S, Cand, I); 6879 6880 // FIXME: this currently happens when we're called from SemaInit 6881 // when user-conversion overload fails. Figure out how to handle 6882 // those conditions and diagnose them well. 6883 return S.NoteOverloadCandidate(Fn); 6884 } 6885 } 6886} 6887 6888void NoteSurrogateCandidate(Sema &S, OverloadCandidate *Cand) { 6889 // Desugar the type of the surrogate down to a function type, 6890 // retaining as many typedefs as possible while still showing 6891 // the function type (and, therefore, its parameter types). 6892 QualType FnType = Cand->Surrogate->getConversionType(); 6893 bool isLValueReference = false; 6894 bool isRValueReference = false; 6895 bool isPointer = false; 6896 if (const LValueReferenceType *FnTypeRef = 6897 FnType->getAs<LValueReferenceType>()) { 6898 FnType = FnTypeRef->getPointeeType(); 6899 isLValueReference = true; 6900 } else if (const RValueReferenceType *FnTypeRef = 6901 FnType->getAs<RValueReferenceType>()) { 6902 FnType = FnTypeRef->getPointeeType(); 6903 isRValueReference = true; 6904 } 6905 if (const PointerType *FnTypePtr = FnType->getAs<PointerType>()) { 6906 FnType = FnTypePtr->getPointeeType(); 6907 isPointer = true; 6908 } 6909 // Desugar down to a function type. 6910 FnType = QualType(FnType->getAs<FunctionType>(), 0); 6911 // Reconstruct the pointer/reference as appropriate. 6912 if (isPointer) FnType = S.Context.getPointerType(FnType); 6913 if (isRValueReference) FnType = S.Context.getRValueReferenceType(FnType); 6914 if (isLValueReference) FnType = S.Context.getLValueReferenceType(FnType); 6915 6916 S.Diag(Cand->Surrogate->getLocation(), diag::note_ovl_surrogate_cand) 6917 << FnType; 6918 MaybeEmitInheritedConstructorNote(S, Cand->Surrogate); 6919} 6920 6921void NoteBuiltinOperatorCandidate(Sema &S, 6922 const char *Opc, 6923 SourceLocation OpLoc, 6924 OverloadCandidate *Cand) { 6925 assert(Cand->Conversions.size() <= 2 && "builtin operator is not binary"); 6926 std::string TypeStr("operator"); 6927 TypeStr += Opc; 6928 TypeStr += "("; 6929 TypeStr += Cand->BuiltinTypes.ParamTypes[0].getAsString(); 6930 if (Cand->Conversions.size() == 1) { 6931 TypeStr += ")"; 6932 S.Diag(OpLoc, diag::note_ovl_builtin_unary_candidate) << TypeStr; 6933 } else { 6934 TypeStr += ", "; 6935 TypeStr += Cand->BuiltinTypes.ParamTypes[1].getAsString(); 6936 TypeStr += ")"; 6937 S.Diag(OpLoc, diag::note_ovl_builtin_binary_candidate) << TypeStr; 6938 } 6939} 6940 6941void NoteAmbiguousUserConversions(Sema &S, SourceLocation OpLoc, 6942 OverloadCandidate *Cand) { 6943 unsigned NoOperands = Cand->Conversions.size(); 6944 for (unsigned ArgIdx = 0; ArgIdx < NoOperands; ++ArgIdx) { 6945 const ImplicitConversionSequence &ICS = Cand->Conversions[ArgIdx]; 6946 if (ICS.isBad()) break; // all meaningless after first invalid 6947 if (!ICS.isAmbiguous()) continue; 6948 6949 ICS.DiagnoseAmbiguousConversion(S, OpLoc, 6950 S.PDiag(diag::note_ambiguous_type_conversion)); 6951 } 6952} 6953 6954SourceLocation GetLocationForCandidate(const OverloadCandidate *Cand) { 6955 if (Cand->Function) 6956 return Cand->Function->getLocation(); 6957 if (Cand->IsSurrogate) 6958 return Cand->Surrogate->getLocation(); 6959 return SourceLocation(); 6960} 6961 6962struct CompareOverloadCandidatesForDisplay { 6963 Sema &S; 6964 CompareOverloadCandidatesForDisplay(Sema &S) : S(S) {} 6965 6966 bool operator()(const OverloadCandidate *L, 6967 const OverloadCandidate *R) { 6968 // Fast-path this check. 6969 if (L == R) return false; 6970 6971 // Order first by viability. 6972 if (L->Viable) { 6973 if (!R->Viable) return true; 6974 6975 // TODO: introduce a tri-valued comparison for overload 6976 // candidates. Would be more worthwhile if we had a sort 6977 // that could exploit it. 6978 if (isBetterOverloadCandidate(S, *L, *R, SourceLocation())) return true; 6979 if (isBetterOverloadCandidate(S, *R, *L, SourceLocation())) return false; 6980 } else if (R->Viable) 6981 return false; 6982 6983 assert(L->Viable == R->Viable); 6984 6985 // Criteria by which we can sort non-viable candidates: 6986 if (!L->Viable) { 6987 // 1. Arity mismatches come after other candidates. 6988 if (L->FailureKind == ovl_fail_too_many_arguments || 6989 L->FailureKind == ovl_fail_too_few_arguments) 6990 return false; 6991 if (R->FailureKind == ovl_fail_too_many_arguments || 6992 R->FailureKind == ovl_fail_too_few_arguments) 6993 return true; 6994 6995 // 2. Bad conversions come first and are ordered by the number 6996 // of bad conversions and quality of good conversions. 6997 if (L->FailureKind == ovl_fail_bad_conversion) { 6998 if (R->FailureKind != ovl_fail_bad_conversion) 6999 return true; 7000 7001 // If there's any ordering between the defined conversions... 7002 // FIXME: this might not be transitive. 7003 assert(L->Conversions.size() == R->Conversions.size()); 7004 7005 int leftBetter = 0; 7006 unsigned I = (L->IgnoreObjectArgument || R->IgnoreObjectArgument); 7007 for (unsigned E = L->Conversions.size(); I != E; ++I) { 7008 switch (CompareImplicitConversionSequences(S, 7009 L->Conversions[I], 7010 R->Conversions[I])) { 7011 case ImplicitConversionSequence::Better: 7012 leftBetter++; 7013 break; 7014 7015 case ImplicitConversionSequence::Worse: 7016 leftBetter--; 7017 break; 7018 7019 case ImplicitConversionSequence::Indistinguishable: 7020 break; 7021 } 7022 } 7023 if (leftBetter > 0) return true; 7024 if (leftBetter < 0) return false; 7025 7026 } else if (R->FailureKind == ovl_fail_bad_conversion) 7027 return false; 7028 7029 // TODO: others? 7030 } 7031 7032 // Sort everything else by location. 7033 SourceLocation LLoc = GetLocationForCandidate(L); 7034 SourceLocation RLoc = GetLocationForCandidate(R); 7035 7036 // Put candidates without locations (e.g. builtins) at the end. 7037 if (LLoc.isInvalid()) return false; 7038 if (RLoc.isInvalid()) return true; 7039 7040 return S.SourceMgr.isBeforeInTranslationUnit(LLoc, RLoc); 7041 } 7042}; 7043 7044/// CompleteNonViableCandidate - Normally, overload resolution only 7045/// computes up to the first 7046void CompleteNonViableCandidate(Sema &S, OverloadCandidate *Cand, 7047 Expr **Args, unsigned NumArgs) { 7048 assert(!Cand->Viable); 7049 7050 // Don't do anything on failures other than bad conversion. 7051 if (Cand->FailureKind != ovl_fail_bad_conversion) return; 7052 7053 // Skip forward to the first bad conversion. 7054 unsigned ConvIdx = (Cand->IgnoreObjectArgument ? 1 : 0); 7055 unsigned ConvCount = Cand->Conversions.size(); 7056 while (true) { 7057 assert(ConvIdx != ConvCount && "no bad conversion in candidate"); 7058 ConvIdx++; 7059 if (Cand->Conversions[ConvIdx - 1].isBad()) 7060 break; 7061 } 7062 7063 if (ConvIdx == ConvCount) 7064 return; 7065 7066 assert(!Cand->Conversions[ConvIdx].isInitialized() && 7067 "remaining conversion is initialized?"); 7068 7069 // FIXME: this should probably be preserved from the overload 7070 // operation somehow. 7071 bool SuppressUserConversions = false; 7072 7073 const FunctionProtoType* Proto; 7074 unsigned ArgIdx = ConvIdx; 7075 7076 if (Cand->IsSurrogate) { 7077 QualType ConvType 7078 = Cand->Surrogate->getConversionType().getNonReferenceType(); 7079 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 7080 ConvType = ConvPtrType->getPointeeType(); 7081 Proto = ConvType->getAs<FunctionProtoType>(); 7082 ArgIdx--; 7083 } else if (Cand->Function) { 7084 Proto = Cand->Function->getType()->getAs<FunctionProtoType>(); 7085 if (isa<CXXMethodDecl>(Cand->Function) && 7086 !isa<CXXConstructorDecl>(Cand->Function)) 7087 ArgIdx--; 7088 } else { 7089 // Builtin binary operator with a bad first conversion. 7090 assert(ConvCount <= 3); 7091 for (; ConvIdx != ConvCount; ++ConvIdx) 7092 Cand->Conversions[ConvIdx] 7093 = TryCopyInitialization(S, Args[ConvIdx], 7094 Cand->BuiltinTypes.ParamTypes[ConvIdx], 7095 SuppressUserConversions, 7096 /*InOverloadResolution*/ true); 7097 return; 7098 } 7099 7100 // Fill in the rest of the conversions. 7101 unsigned NumArgsInProto = Proto->getNumArgs(); 7102 for (; ConvIdx != ConvCount; ++ConvIdx, ++ArgIdx) { 7103 if (ArgIdx < NumArgsInProto) 7104 Cand->Conversions[ConvIdx] 7105 = TryCopyInitialization(S, Args[ArgIdx], Proto->getArgType(ArgIdx), 7106 SuppressUserConversions, 7107 /*InOverloadResolution=*/true); 7108 else 7109 Cand->Conversions[ConvIdx].setEllipsis(); 7110 } 7111} 7112 7113} // end anonymous namespace 7114 7115/// PrintOverloadCandidates - When overload resolution fails, prints 7116/// diagnostic messages containing the candidates in the candidate 7117/// set. 7118void OverloadCandidateSet::NoteCandidates(Sema &S, 7119 OverloadCandidateDisplayKind OCD, 7120 Expr **Args, unsigned NumArgs, 7121 const char *Opc, 7122 SourceLocation OpLoc) { 7123 // Sort the candidates by viability and position. Sorting directly would 7124 // be prohibitive, so we make a set of pointers and sort those. 7125 llvm::SmallVector<OverloadCandidate*, 32> Cands; 7126 if (OCD == OCD_AllCandidates) Cands.reserve(size()); 7127 for (iterator Cand = begin(), LastCand = end(); Cand != LastCand; ++Cand) { 7128 if (Cand->Viable) 7129 Cands.push_back(Cand); 7130 else if (OCD == OCD_AllCandidates) { 7131 CompleteNonViableCandidate(S, Cand, Args, NumArgs); 7132 if (Cand->Function || Cand->IsSurrogate) 7133 Cands.push_back(Cand); 7134 // Otherwise, this a non-viable builtin candidate. We do not, in general, 7135 // want to list every possible builtin candidate. 7136 } 7137 } 7138 7139 std::sort(Cands.begin(), Cands.end(), 7140 CompareOverloadCandidatesForDisplay(S)); 7141 7142 bool ReportedAmbiguousConversions = false; 7143 7144 llvm::SmallVectorImpl<OverloadCandidate*>::iterator I, E; 7145 const Diagnostic::OverloadsShown ShowOverloads = S.Diags.getShowOverloads(); 7146 unsigned CandsShown = 0; 7147 for (I = Cands.begin(), E = Cands.end(); I != E; ++I) { 7148 OverloadCandidate *Cand = *I; 7149 7150 // Set an arbitrary limit on the number of candidate functions we'll spam 7151 // the user with. FIXME: This limit should depend on details of the 7152 // candidate list. 7153 if (CandsShown >= 4 && ShowOverloads == Diagnostic::Ovl_Best) { 7154 break; 7155 } 7156 ++CandsShown; 7157 7158 if (Cand->Function) 7159 NoteFunctionCandidate(S, Cand, Args, NumArgs); 7160 else if (Cand->IsSurrogate) 7161 NoteSurrogateCandidate(S, Cand); 7162 else { 7163 assert(Cand->Viable && 7164 "Non-viable built-in candidates are not added to Cands."); 7165 // Generally we only see ambiguities including viable builtin 7166 // operators if overload resolution got screwed up by an 7167 // ambiguous user-defined conversion. 7168 // 7169 // FIXME: It's quite possible for different conversions to see 7170 // different ambiguities, though. 7171 if (!ReportedAmbiguousConversions) { 7172 NoteAmbiguousUserConversions(S, OpLoc, Cand); 7173 ReportedAmbiguousConversions = true; 7174 } 7175 7176 // If this is a viable builtin, print it. 7177 NoteBuiltinOperatorCandidate(S, Opc, OpLoc, Cand); 7178 } 7179 } 7180 7181 if (I != E) 7182 S.Diag(OpLoc, diag::note_ovl_too_many_candidates) << int(E - I); 7183} 7184 7185// [PossiblyAFunctionType] --> [Return] 7186// NonFunctionType --> NonFunctionType 7187// R (A) --> R(A) 7188// R (*)(A) --> R (A) 7189// R (&)(A) --> R (A) 7190// R (S::*)(A) --> R (A) 7191QualType Sema::ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType) { 7192 QualType Ret = PossiblyAFunctionType; 7193 if (const PointerType *ToTypePtr = 7194 PossiblyAFunctionType->getAs<PointerType>()) 7195 Ret = ToTypePtr->getPointeeType(); 7196 else if (const ReferenceType *ToTypeRef = 7197 PossiblyAFunctionType->getAs<ReferenceType>()) 7198 Ret = ToTypeRef->getPointeeType(); 7199 else if (const MemberPointerType *MemTypePtr = 7200 PossiblyAFunctionType->getAs<MemberPointerType>()) 7201 Ret = MemTypePtr->getPointeeType(); 7202 Ret = 7203 Context.getCanonicalType(Ret).getUnqualifiedType(); 7204 return Ret; 7205} 7206 7207// A helper class to help with address of function resolution 7208// - allows us to avoid passing around all those ugly parameters 7209class AddressOfFunctionResolver 7210{ 7211 Sema& S; 7212 Expr* SourceExpr; 7213 const QualType& TargetType; 7214 QualType TargetFunctionType; // Extracted function type from target type 7215 7216 bool Complain; 7217 //DeclAccessPair& ResultFunctionAccessPair; 7218 ASTContext& Context; 7219 7220 bool TargetTypeIsNonStaticMemberFunction; 7221 bool FoundNonTemplateFunction; 7222 7223 OverloadExpr::FindResult OvlExprInfo; 7224 OverloadExpr *OvlExpr; 7225 TemplateArgumentListInfo OvlExplicitTemplateArgs; 7226 llvm::SmallVector<std::pair<DeclAccessPair, FunctionDecl*>, 4> Matches; 7227 7228public: 7229 AddressOfFunctionResolver(Sema &S, Expr* SourceExpr, 7230 const QualType& TargetType, bool Complain) 7231 : S(S), SourceExpr(SourceExpr), TargetType(TargetType), 7232 Complain(Complain), Context(S.getASTContext()), 7233 TargetTypeIsNonStaticMemberFunction( 7234 !!TargetType->getAs<MemberPointerType>()), 7235 FoundNonTemplateFunction(false), 7236 OvlExprInfo(OverloadExpr::find(SourceExpr)), 7237 OvlExpr(OvlExprInfo.Expression) 7238 { 7239 ExtractUnqualifiedFunctionTypeFromTargetType(); 7240 7241 if (!TargetFunctionType->isFunctionType()) { 7242 if (OvlExpr->hasExplicitTemplateArgs()) { 7243 DeclAccessPair dap; 7244 if (FunctionDecl* Fn = S.ResolveSingleFunctionTemplateSpecialization( 7245 OvlExpr, false, &dap) ) { 7246 7247 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 7248 if (!Method->isStatic()) { 7249 // If the target type is a non-function type and the function 7250 // found is a non-static member function, pretend as if that was 7251 // the target, it's the only possible type to end up with. 7252 TargetTypeIsNonStaticMemberFunction = true; 7253 7254 // And skip adding the function if its not in the proper form. 7255 // We'll diagnose this due to an empty set of functions. 7256 if (!OvlExprInfo.HasFormOfMemberPointer) 7257 return; 7258 } 7259 } 7260 7261 Matches.push_back(std::make_pair(dap,Fn)); 7262 } 7263 } 7264 return; 7265 } 7266 7267 if (OvlExpr->hasExplicitTemplateArgs()) 7268 OvlExpr->getExplicitTemplateArgs().copyInto(OvlExplicitTemplateArgs); 7269 7270 if (FindAllFunctionsThatMatchTargetTypeExactly()) { 7271 // C++ [over.over]p4: 7272 // If more than one function is selected, [...] 7273 if (Matches.size() > 1) { 7274 if (FoundNonTemplateFunction) 7275 EliminateAllTemplateMatches(); 7276 else 7277 EliminateAllExceptMostSpecializedTemplate(); 7278 } 7279 } 7280 } 7281 7282private: 7283 bool isTargetTypeAFunction() const { 7284 return TargetFunctionType->isFunctionType(); 7285 } 7286 7287 // [ToType] [Return] 7288 7289 // R (*)(A) --> R (A), IsNonStaticMemberFunction = false 7290 // R (&)(A) --> R (A), IsNonStaticMemberFunction = false 7291 // R (S::*)(A) --> R (A), IsNonStaticMemberFunction = true 7292 void inline ExtractUnqualifiedFunctionTypeFromTargetType() { 7293 TargetFunctionType = S.ExtractUnqualifiedFunctionType(TargetType); 7294 } 7295 7296 // return true if any matching specializations were found 7297 bool AddMatchingTemplateFunction(FunctionTemplateDecl* FunctionTemplate, 7298 const DeclAccessPair& CurAccessFunPair) { 7299 if (CXXMethodDecl *Method 7300 = dyn_cast<CXXMethodDecl>(FunctionTemplate->getTemplatedDecl())) { 7301 // Skip non-static function templates when converting to pointer, and 7302 // static when converting to member pointer. 7303 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 7304 return false; 7305 } 7306 else if (TargetTypeIsNonStaticMemberFunction) 7307 return false; 7308 7309 // C++ [over.over]p2: 7310 // If the name is a function template, template argument deduction is 7311 // done (14.8.2.2), and if the argument deduction succeeds, the 7312 // resulting template argument list is used to generate a single 7313 // function template specialization, which is added to the set of 7314 // overloaded functions considered. 7315 FunctionDecl *Specialization = 0; 7316 TemplateDeductionInfo Info(Context, OvlExpr->getNameLoc()); 7317 if (Sema::TemplateDeductionResult Result 7318 = S.DeduceTemplateArguments(FunctionTemplate, 7319 &OvlExplicitTemplateArgs, 7320 TargetFunctionType, Specialization, 7321 Info)) { 7322 // FIXME: make a note of the failed deduction for diagnostics. 7323 (void)Result; 7324 return false; 7325 } 7326 7327 // Template argument deduction ensures that we have an exact match. 7328 // This function template specicalization works. 7329 Specialization = cast<FunctionDecl>(Specialization->getCanonicalDecl()); 7330 assert(TargetFunctionType 7331 == Context.getCanonicalType(Specialization->getType())); 7332 Matches.push_back(std::make_pair(CurAccessFunPair, Specialization)); 7333 return true; 7334 } 7335 7336 bool AddMatchingNonTemplateFunction(NamedDecl* Fn, 7337 const DeclAccessPair& CurAccessFunPair) { 7338 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 7339 // Skip non-static functions when converting to pointer, and static 7340 // when converting to member pointer. 7341 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 7342 return false; 7343 } 7344 else if (TargetTypeIsNonStaticMemberFunction) 7345 return false; 7346 7347 if (FunctionDecl *FunDecl = dyn_cast<FunctionDecl>(Fn)) { 7348 QualType ResultTy; 7349 if (Context.hasSameUnqualifiedType(TargetFunctionType, 7350 FunDecl->getType()) || 7351 IsNoReturnConversion(Context, FunDecl->getType(), TargetFunctionType, 7352 ResultTy)) { 7353 Matches.push_back(std::make_pair(CurAccessFunPair, 7354 cast<FunctionDecl>(FunDecl->getCanonicalDecl()))); 7355 FoundNonTemplateFunction = true; 7356 return true; 7357 } 7358 } 7359 7360 return false; 7361 } 7362 7363 bool FindAllFunctionsThatMatchTargetTypeExactly() { 7364 bool Ret = false; 7365 7366 // If the overload expression doesn't have the form of a pointer to 7367 // member, don't try to convert it to a pointer-to-member type. 7368 if (IsInvalidFormOfPointerToMemberFunction()) 7369 return false; 7370 7371 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 7372 E = OvlExpr->decls_end(); 7373 I != E; ++I) { 7374 // Look through any using declarations to find the underlying function. 7375 NamedDecl *Fn = (*I)->getUnderlyingDecl(); 7376 7377 // C++ [over.over]p3: 7378 // Non-member functions and static member functions match 7379 // targets of type "pointer-to-function" or "reference-to-function." 7380 // Nonstatic member functions match targets of 7381 // type "pointer-to-member-function." 7382 // Note that according to DR 247, the containing class does not matter. 7383 if (FunctionTemplateDecl *FunctionTemplate 7384 = dyn_cast<FunctionTemplateDecl>(Fn)) { 7385 if (AddMatchingTemplateFunction(FunctionTemplate, I.getPair())) 7386 Ret = true; 7387 } 7388 // If we have explicit template arguments supplied, skip non-templates. 7389 else if (!OvlExpr->hasExplicitTemplateArgs() && 7390 AddMatchingNonTemplateFunction(Fn, I.getPair())) 7391 Ret = true; 7392 } 7393 assert(Ret || Matches.empty()); 7394 return Ret; 7395 } 7396 7397 void EliminateAllExceptMostSpecializedTemplate() { 7398 // [...] and any given function template specialization F1 is 7399 // eliminated if the set contains a second function template 7400 // specialization whose function template is more specialized 7401 // than the function template of F1 according to the partial 7402 // ordering rules of 14.5.5.2. 7403 7404 // The algorithm specified above is quadratic. We instead use a 7405 // two-pass algorithm (similar to the one used to identify the 7406 // best viable function in an overload set) that identifies the 7407 // best function template (if it exists). 7408 7409 UnresolvedSet<4> MatchesCopy; // TODO: avoid! 7410 for (unsigned I = 0, E = Matches.size(); I != E; ++I) 7411 MatchesCopy.addDecl(Matches[I].second, Matches[I].first.getAccess()); 7412 7413 UnresolvedSetIterator Result = 7414 S.getMostSpecialized(MatchesCopy.begin(), MatchesCopy.end(), 7415 TPOC_Other, 0, SourceExpr->getLocStart(), 7416 S.PDiag(), 7417 S.PDiag(diag::err_addr_ovl_ambiguous) 7418 << Matches[0].second->getDeclName(), 7419 S.PDiag(diag::note_ovl_candidate) 7420 << (unsigned) oc_function_template, 7421 Complain); 7422 7423 if (Result != MatchesCopy.end()) { 7424 // Make it the first and only element 7425 Matches[0].first = Matches[Result - MatchesCopy.begin()].first; 7426 Matches[0].second = cast<FunctionDecl>(*Result); 7427 Matches.resize(1); 7428 } 7429 } 7430 7431 void EliminateAllTemplateMatches() { 7432 // [...] any function template specializations in the set are 7433 // eliminated if the set also contains a non-template function, [...] 7434 for (unsigned I = 0, N = Matches.size(); I != N; ) { 7435 if (Matches[I].second->getPrimaryTemplate() == 0) 7436 ++I; 7437 else { 7438 Matches[I] = Matches[--N]; 7439 Matches.set_size(N); 7440 } 7441 } 7442 } 7443 7444public: 7445 void ComplainNoMatchesFound() const { 7446 assert(Matches.empty()); 7447 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_no_viable) 7448 << OvlExpr->getName() << TargetFunctionType 7449 << OvlExpr->getSourceRange(); 7450 S.NoteAllOverloadCandidates(OvlExpr); 7451 } 7452 7453 bool IsInvalidFormOfPointerToMemberFunction() const { 7454 return TargetTypeIsNonStaticMemberFunction && 7455 !OvlExprInfo.HasFormOfMemberPointer; 7456 } 7457 7458 void ComplainIsInvalidFormOfPointerToMemberFunction() const { 7459 // TODO: Should we condition this on whether any functions might 7460 // have matched, or is it more appropriate to do that in callers? 7461 // TODO: a fixit wouldn't hurt. 7462 S.Diag(OvlExpr->getNameLoc(), diag::err_addr_ovl_no_qualifier) 7463 << TargetType << OvlExpr->getSourceRange(); 7464 } 7465 7466 void ComplainOfInvalidConversion() const { 7467 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_not_func_ptrref) 7468 << OvlExpr->getName() << TargetType; 7469 } 7470 7471 void ComplainMultipleMatchesFound() const { 7472 assert(Matches.size() > 1); 7473 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_ambiguous) 7474 << OvlExpr->getName() 7475 << OvlExpr->getSourceRange(); 7476 S.NoteAllOverloadCandidates(OvlExpr); 7477 } 7478 7479 int getNumMatches() const { return Matches.size(); } 7480 7481 FunctionDecl* getMatchingFunctionDecl() const { 7482 if (Matches.size() != 1) return 0; 7483 return Matches[0].second; 7484 } 7485 7486 const DeclAccessPair* getMatchingFunctionAccessPair() const { 7487 if (Matches.size() != 1) return 0; 7488 return &Matches[0].first; 7489 } 7490}; 7491 7492/// ResolveAddressOfOverloadedFunction - Try to resolve the address of 7493/// an overloaded function (C++ [over.over]), where @p From is an 7494/// expression with overloaded function type and @p ToType is the type 7495/// we're trying to resolve to. For example: 7496/// 7497/// @code 7498/// int f(double); 7499/// int f(int); 7500/// 7501/// int (*pfd)(double) = f; // selects f(double) 7502/// @endcode 7503/// 7504/// This routine returns the resulting FunctionDecl if it could be 7505/// resolved, and NULL otherwise. When @p Complain is true, this 7506/// routine will emit diagnostics if there is an error. 7507FunctionDecl * 7508Sema::ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr, QualType TargetType, 7509 bool Complain, 7510 DeclAccessPair &FoundResult) { 7511 7512 assert(AddressOfExpr->getType() == Context.OverloadTy); 7513 7514 AddressOfFunctionResolver Resolver(*this, AddressOfExpr, TargetType, Complain); 7515 int NumMatches = Resolver.getNumMatches(); 7516 FunctionDecl* Fn = 0; 7517 if ( NumMatches == 0 && Complain) { 7518 if (Resolver.IsInvalidFormOfPointerToMemberFunction()) 7519 Resolver.ComplainIsInvalidFormOfPointerToMemberFunction(); 7520 else 7521 Resolver.ComplainNoMatchesFound(); 7522 } 7523 else if (NumMatches > 1 && Complain) 7524 Resolver.ComplainMultipleMatchesFound(); 7525 else if (NumMatches == 1) { 7526 Fn = Resolver.getMatchingFunctionDecl(); 7527 assert(Fn); 7528 FoundResult = *Resolver.getMatchingFunctionAccessPair(); 7529 MarkDeclarationReferenced(AddressOfExpr->getLocStart(), Fn); 7530 if (Complain) 7531 CheckAddressOfMemberAccess(AddressOfExpr, FoundResult); 7532 } 7533 7534 return Fn; 7535} 7536 7537/// \brief Given an expression that refers to an overloaded function, try to 7538/// resolve that overloaded function expression down to a single function. 7539/// 7540/// This routine can only resolve template-ids that refer to a single function 7541/// template, where that template-id refers to a single template whose template 7542/// arguments are either provided by the template-id or have defaults, 7543/// as described in C++0x [temp.arg.explicit]p3. 7544FunctionDecl * 7545Sema::ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl, 7546 bool Complain, 7547 DeclAccessPair *FoundResult) { 7548 // C++ [over.over]p1: 7549 // [...] [Note: any redundant set of parentheses surrounding the 7550 // overloaded function name is ignored (5.1). ] 7551 // C++ [over.over]p1: 7552 // [...] The overloaded function name can be preceded by the & 7553 // operator. 7554 7555 // If we didn't actually find any template-ids, we're done. 7556 if (!ovl->hasExplicitTemplateArgs()) 7557 return 0; 7558 7559 TemplateArgumentListInfo ExplicitTemplateArgs; 7560 ovl->getExplicitTemplateArgs().copyInto(ExplicitTemplateArgs); 7561 7562 // Look through all of the overloaded functions, searching for one 7563 // whose type matches exactly. 7564 FunctionDecl *Matched = 0; 7565 for (UnresolvedSetIterator I = ovl->decls_begin(), 7566 E = ovl->decls_end(); I != E; ++I) { 7567 // C++0x [temp.arg.explicit]p3: 7568 // [...] In contexts where deduction is done and fails, or in contexts 7569 // where deduction is not done, if a template argument list is 7570 // specified and it, along with any default template arguments, 7571 // identifies a single function template specialization, then the 7572 // template-id is an lvalue for the function template specialization. 7573 FunctionTemplateDecl *FunctionTemplate 7574 = cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()); 7575 7576 // C++ [over.over]p2: 7577 // If the name is a function template, template argument deduction is 7578 // done (14.8.2.2), and if the argument deduction succeeds, the 7579 // resulting template argument list is used to generate a single 7580 // function template specialization, which is added to the set of 7581 // overloaded functions considered. 7582 FunctionDecl *Specialization = 0; 7583 TemplateDeductionInfo Info(Context, ovl->getNameLoc()); 7584 if (TemplateDeductionResult Result 7585 = DeduceTemplateArguments(FunctionTemplate, &ExplicitTemplateArgs, 7586 Specialization, Info)) { 7587 // FIXME: make a note of the failed deduction for diagnostics. 7588 (void)Result; 7589 continue; 7590 } 7591 7592 assert(Specialization && "no specialization and no error?"); 7593 7594 // Multiple matches; we can't resolve to a single declaration. 7595 if (Matched) { 7596 if (Complain) { 7597 Diag(ovl->getExprLoc(), diag::err_addr_ovl_ambiguous) 7598 << ovl->getName(); 7599 NoteAllOverloadCandidates(ovl); 7600 } 7601 return 0; 7602 } 7603 7604 Matched = Specialization; 7605 if (FoundResult) *FoundResult = I.getPair(); 7606 } 7607 7608 return Matched; 7609} 7610 7611 7612 7613 7614// Resolve and fix an overloaded expression that 7615// can be resolved because it identifies a single function 7616// template specialization 7617// Last three arguments should only be supplied if Complain = true 7618ExprResult Sema::ResolveAndFixSingleFunctionTemplateSpecialization( 7619 Expr *SrcExpr, bool doFunctionPointerConverion, bool complain, 7620 const SourceRange& OpRangeForComplaining, 7621 QualType DestTypeForComplaining, 7622 unsigned DiagIDForComplaining) { 7623 assert(SrcExpr->getType() == Context.OverloadTy); 7624 7625 OverloadExpr::FindResult ovl = OverloadExpr::find(SrcExpr); 7626 7627 DeclAccessPair found; 7628 ExprResult SingleFunctionExpression; 7629 if (FunctionDecl *fn = ResolveSingleFunctionTemplateSpecialization( 7630 ovl.Expression, /*complain*/ false, &found)) { 7631 if (DiagnoseUseOfDecl(fn, SrcExpr->getSourceRange().getBegin())) 7632 return ExprError(); 7633 7634 // It is only correct to resolve to an instance method if we're 7635 // resolving a form that's permitted to be a pointer to member. 7636 // Otherwise we'll end up making a bound member expression, which 7637 // is illegal in all the contexts we resolve like this. 7638 if (!ovl.HasFormOfMemberPointer && 7639 isa<CXXMethodDecl>(fn) && 7640 cast<CXXMethodDecl>(fn)->isInstance()) { 7641 if (complain) { 7642 Diag(ovl.Expression->getExprLoc(), 7643 diag::err_invalid_use_of_bound_member_func) 7644 << ovl.Expression->getSourceRange(); 7645 // TODO: I believe we only end up here if there's a mix of 7646 // static and non-static candidates (otherwise the expression 7647 // would have 'bound member' type, not 'overload' type). 7648 // Ideally we would note which candidate was chosen and why 7649 // the static candidates were rejected. 7650 } 7651 7652 return ExprError(); 7653 } 7654 7655 // Fix the expresion to refer to 'fn'. 7656 SingleFunctionExpression = 7657 Owned(FixOverloadedFunctionReference(SrcExpr, found, fn)); 7658 7659 // If desired, do function-to-pointer decay. 7660 if (doFunctionPointerConverion) 7661 SingleFunctionExpression = 7662 DefaultFunctionArrayLvalueConversion(SingleFunctionExpression.take()); 7663 } 7664 7665 if (!SingleFunctionExpression.isUsable()) { 7666 if (complain) { 7667 Diag(OpRangeForComplaining.getBegin(), DiagIDForComplaining) 7668 << ovl.Expression->getName() 7669 << DestTypeForComplaining 7670 << OpRangeForComplaining 7671 << ovl.Expression->getQualifierLoc().getSourceRange(); 7672 NoteAllOverloadCandidates(SrcExpr); 7673 } 7674 return ExprError(); 7675 } 7676 7677 return SingleFunctionExpression; 7678} 7679 7680/// \brief Add a single candidate to the overload set. 7681static void AddOverloadedCallCandidate(Sema &S, 7682 DeclAccessPair FoundDecl, 7683 TemplateArgumentListInfo *ExplicitTemplateArgs, 7684 Expr **Args, unsigned NumArgs, 7685 OverloadCandidateSet &CandidateSet, 7686 bool PartialOverloading) { 7687 NamedDecl *Callee = FoundDecl.getDecl(); 7688 if (isa<UsingShadowDecl>(Callee)) 7689 Callee = cast<UsingShadowDecl>(Callee)->getTargetDecl(); 7690 7691 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(Callee)) { 7692 assert(!ExplicitTemplateArgs && "Explicit template arguments?"); 7693 S.AddOverloadCandidate(Func, FoundDecl, Args, NumArgs, CandidateSet, 7694 false, PartialOverloading); 7695 return; 7696 } 7697 7698 if (FunctionTemplateDecl *FuncTemplate 7699 = dyn_cast<FunctionTemplateDecl>(Callee)) { 7700 S.AddTemplateOverloadCandidate(FuncTemplate, FoundDecl, 7701 ExplicitTemplateArgs, 7702 Args, NumArgs, CandidateSet); 7703 return; 7704 } 7705 7706 assert(false && "unhandled case in overloaded call candidate"); 7707 7708 // do nothing? 7709} 7710 7711/// \brief Add the overload candidates named by callee and/or found by argument 7712/// dependent lookup to the given overload set. 7713void Sema::AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE, 7714 Expr **Args, unsigned NumArgs, 7715 OverloadCandidateSet &CandidateSet, 7716 bool PartialOverloading) { 7717 7718#ifndef NDEBUG 7719 // Verify that ArgumentDependentLookup is consistent with the rules 7720 // in C++0x [basic.lookup.argdep]p3: 7721 // 7722 // Let X be the lookup set produced by unqualified lookup (3.4.1) 7723 // and let Y be the lookup set produced by argument dependent 7724 // lookup (defined as follows). If X contains 7725 // 7726 // -- a declaration of a class member, or 7727 // 7728 // -- a block-scope function declaration that is not a 7729 // using-declaration, or 7730 // 7731 // -- a declaration that is neither a function or a function 7732 // template 7733 // 7734 // then Y is empty. 7735 7736 if (ULE->requiresADL()) { 7737 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 7738 E = ULE->decls_end(); I != E; ++I) { 7739 assert(!(*I)->getDeclContext()->isRecord()); 7740 assert(isa<UsingShadowDecl>(*I) || 7741 !(*I)->getDeclContext()->isFunctionOrMethod()); 7742 assert((*I)->getUnderlyingDecl()->isFunctionOrFunctionTemplate()); 7743 } 7744 } 7745#endif 7746 7747 // It would be nice to avoid this copy. 7748 TemplateArgumentListInfo TABuffer; 7749 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 7750 if (ULE->hasExplicitTemplateArgs()) { 7751 ULE->copyTemplateArgumentsInto(TABuffer); 7752 ExplicitTemplateArgs = &TABuffer; 7753 } 7754 7755 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 7756 E = ULE->decls_end(); I != E; ++I) 7757 AddOverloadedCallCandidate(*this, I.getPair(), ExplicitTemplateArgs, 7758 Args, NumArgs, CandidateSet, 7759 PartialOverloading); 7760 7761 if (ULE->requiresADL()) 7762 AddArgumentDependentLookupCandidates(ULE->getName(), /*Operator*/ false, 7763 Args, NumArgs, 7764 ExplicitTemplateArgs, 7765 CandidateSet, 7766 PartialOverloading, 7767 ULE->isStdAssociatedNamespace()); 7768} 7769 7770/// Attempts to recover from a call where no functions were found. 7771/// 7772/// Returns true if new candidates were found. 7773static ExprResult 7774BuildRecoveryCallExpr(Sema &SemaRef, Scope *S, Expr *Fn, 7775 UnresolvedLookupExpr *ULE, 7776 SourceLocation LParenLoc, 7777 Expr **Args, unsigned NumArgs, 7778 SourceLocation RParenLoc) { 7779 7780 CXXScopeSpec SS; 7781 SS.Adopt(ULE->getQualifierLoc()); 7782 7783 TemplateArgumentListInfo TABuffer; 7784 const TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 7785 if (ULE->hasExplicitTemplateArgs()) { 7786 ULE->copyTemplateArgumentsInto(TABuffer); 7787 ExplicitTemplateArgs = &TABuffer; 7788 } 7789 7790 LookupResult R(SemaRef, ULE->getName(), ULE->getNameLoc(), 7791 Sema::LookupOrdinaryName); 7792 if (SemaRef.DiagnoseEmptyLookup(S, SS, R, Sema::CTC_Expression)) 7793 return ExprError(); 7794 7795 assert(!R.empty() && "lookup results empty despite recovery"); 7796 7797 // Build an implicit member call if appropriate. Just drop the 7798 // casts and such from the call, we don't really care. 7799 ExprResult NewFn = ExprError(); 7800 if ((*R.begin())->isCXXClassMember()) 7801 NewFn = SemaRef.BuildPossibleImplicitMemberExpr(SS, R, 7802 ExplicitTemplateArgs); 7803 else if (ExplicitTemplateArgs) 7804 NewFn = SemaRef.BuildTemplateIdExpr(SS, R, false, *ExplicitTemplateArgs); 7805 else 7806 NewFn = SemaRef.BuildDeclarationNameExpr(SS, R, false); 7807 7808 if (NewFn.isInvalid()) 7809 return ExprError(); 7810 7811 // This shouldn't cause an infinite loop because we're giving it 7812 // an expression with non-empty lookup results, which should never 7813 // end up here. 7814 return SemaRef.ActOnCallExpr(/*Scope*/ 0, NewFn.take(), LParenLoc, 7815 MultiExprArg(Args, NumArgs), RParenLoc); 7816} 7817 7818/// ResolveOverloadedCallFn - Given the call expression that calls Fn 7819/// (which eventually refers to the declaration Func) and the call 7820/// arguments Args/NumArgs, attempt to resolve the function call down 7821/// to a specific function. If overload resolution succeeds, returns 7822/// the function declaration produced by overload 7823/// resolution. Otherwise, emits diagnostics, deletes all of the 7824/// arguments and Fn, and returns NULL. 7825ExprResult 7826Sema::BuildOverloadedCallExpr(Scope *S, Expr *Fn, UnresolvedLookupExpr *ULE, 7827 SourceLocation LParenLoc, 7828 Expr **Args, unsigned NumArgs, 7829 SourceLocation RParenLoc, 7830 Expr *ExecConfig) { 7831#ifndef NDEBUG 7832 if (ULE->requiresADL()) { 7833 // To do ADL, we must have found an unqualified name. 7834 assert(!ULE->getQualifier() && "qualified name with ADL"); 7835 7836 // We don't perform ADL for implicit declarations of builtins. 7837 // Verify that this was correctly set up. 7838 FunctionDecl *F; 7839 if (ULE->decls_begin() + 1 == ULE->decls_end() && 7840 (F = dyn_cast<FunctionDecl>(*ULE->decls_begin())) && 7841 F->getBuiltinID() && F->isImplicit()) 7842 assert(0 && "performing ADL for builtin"); 7843 7844 // We don't perform ADL in C. 7845 assert(getLangOptions().CPlusPlus && "ADL enabled in C"); 7846 } else 7847 assert(!ULE->isStdAssociatedNamespace() && 7848 "std is associated namespace but not doing ADL"); 7849#endif 7850 7851 OverloadCandidateSet CandidateSet(Fn->getExprLoc()); 7852 7853 // Add the functions denoted by the callee to the set of candidate 7854 // functions, including those from argument-dependent lookup. 7855 AddOverloadedCallCandidates(ULE, Args, NumArgs, CandidateSet); 7856 7857 // If we found nothing, try to recover. 7858 // AddRecoveryCallCandidates diagnoses the error itself, so we just 7859 // bailout out if it fails. 7860 if (CandidateSet.empty()) 7861 return BuildRecoveryCallExpr(*this, S, Fn, ULE, LParenLoc, Args, NumArgs, 7862 RParenLoc); 7863 7864 OverloadCandidateSet::iterator Best; 7865 switch (CandidateSet.BestViableFunction(*this, Fn->getLocStart(), Best)) { 7866 case OR_Success: { 7867 FunctionDecl *FDecl = Best->Function; 7868 MarkDeclarationReferenced(Fn->getExprLoc(), FDecl); 7869 CheckUnresolvedLookupAccess(ULE, Best->FoundDecl); 7870 DiagnoseUseOfDecl(FDecl? FDecl : Best->FoundDecl.getDecl(), 7871 ULE->getNameLoc()); 7872 Fn = FixOverloadedFunctionReference(Fn, Best->FoundDecl, FDecl); 7873 return BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, NumArgs, RParenLoc, 7874 ExecConfig); 7875 } 7876 7877 case OR_No_Viable_Function: 7878 Diag(Fn->getSourceRange().getBegin(), 7879 diag::err_ovl_no_viable_function_in_call) 7880 << ULE->getName() << Fn->getSourceRange(); 7881 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 7882 break; 7883 7884 case OR_Ambiguous: 7885 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_ambiguous_call) 7886 << ULE->getName() << Fn->getSourceRange(); 7887 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 7888 break; 7889 7890 case OR_Deleted: 7891 { 7892 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_deleted_call) 7893 << Best->Function->isDeleted() 7894 << ULE->getName() 7895 << getDeletedOrUnavailableSuffix(Best->Function) 7896 << Fn->getSourceRange(); 7897 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 7898 } 7899 break; 7900 } 7901 7902 // Overload resolution failed. 7903 return ExprError(); 7904} 7905 7906static bool IsOverloaded(const UnresolvedSetImpl &Functions) { 7907 return Functions.size() > 1 || 7908 (Functions.size() == 1 && isa<FunctionTemplateDecl>(*Functions.begin())); 7909} 7910 7911/// \brief Create a unary operation that may resolve to an overloaded 7912/// operator. 7913/// 7914/// \param OpLoc The location of the operator itself (e.g., '*'). 7915/// 7916/// \param OpcIn The UnaryOperator::Opcode that describes this 7917/// operator. 7918/// 7919/// \param Functions The set of non-member functions that will be 7920/// considered by overload resolution. The caller needs to build this 7921/// set based on the context using, e.g., 7922/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 7923/// set should not contain any member functions; those will be added 7924/// by CreateOverloadedUnaryOp(). 7925/// 7926/// \param input The input argument. 7927ExprResult 7928Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, unsigned OpcIn, 7929 const UnresolvedSetImpl &Fns, 7930 Expr *Input) { 7931 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 7932 7933 OverloadedOperatorKind Op = UnaryOperator::getOverloadedOperator(Opc); 7934 assert(Op != OO_None && "Invalid opcode for overloaded unary operator"); 7935 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 7936 // TODO: provide better source location info. 7937 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 7938 7939 if (Input->getObjectKind() == OK_ObjCProperty) { 7940 ExprResult Result = ConvertPropertyForRValue(Input); 7941 if (Result.isInvalid()) 7942 return ExprError(); 7943 Input = Result.take(); 7944 } 7945 7946 Expr *Args[2] = { Input, 0 }; 7947 unsigned NumArgs = 1; 7948 7949 // For post-increment and post-decrement, add the implicit '0' as 7950 // the second argument, so that we know this is a post-increment or 7951 // post-decrement. 7952 if (Opc == UO_PostInc || Opc == UO_PostDec) { 7953 llvm::APSInt Zero(Context.getTypeSize(Context.IntTy), false); 7954 Args[1] = IntegerLiteral::Create(Context, Zero, Context.IntTy, 7955 SourceLocation()); 7956 NumArgs = 2; 7957 } 7958 7959 if (Input->isTypeDependent()) { 7960 if (Fns.empty()) 7961 return Owned(new (Context) UnaryOperator(Input, 7962 Opc, 7963 Context.DependentTy, 7964 VK_RValue, OK_Ordinary, 7965 OpLoc)); 7966 7967 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 7968 UnresolvedLookupExpr *Fn 7969 = UnresolvedLookupExpr::Create(Context, NamingClass, 7970 NestedNameSpecifierLoc(), OpNameInfo, 7971 /*ADL*/ true, IsOverloaded(Fns), 7972 Fns.begin(), Fns.end()); 7973 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 7974 &Args[0], NumArgs, 7975 Context.DependentTy, 7976 VK_RValue, 7977 OpLoc)); 7978 } 7979 7980 // Build an empty overload set. 7981 OverloadCandidateSet CandidateSet(OpLoc); 7982 7983 // Add the candidates from the given function set. 7984 AddFunctionCandidates(Fns, &Args[0], NumArgs, CandidateSet, false); 7985 7986 // Add operator candidates that are member functions. 7987 AddMemberOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 7988 7989 // Add candidates from ADL. 7990 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 7991 Args, NumArgs, 7992 /*ExplicitTemplateArgs*/ 0, 7993 CandidateSet); 7994 7995 // Add builtin operator candidates. 7996 AddBuiltinOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 7997 7998 // Perform overload resolution. 7999 OverloadCandidateSet::iterator Best; 8000 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8001 case OR_Success: { 8002 // We found a built-in operator or an overloaded operator. 8003 FunctionDecl *FnDecl = Best->Function; 8004 8005 if (FnDecl) { 8006 // We matched an overloaded operator. Build a call to that 8007 // operator. 8008 8009 MarkDeclarationReferenced(OpLoc, FnDecl); 8010 8011 // Convert the arguments. 8012 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 8013 CheckMemberOperatorAccess(OpLoc, Args[0], 0, Best->FoundDecl); 8014 8015 ExprResult InputRes = 8016 PerformObjectArgumentInitialization(Input, /*Qualifier=*/0, 8017 Best->FoundDecl, Method); 8018 if (InputRes.isInvalid()) 8019 return ExprError(); 8020 Input = InputRes.take(); 8021 } else { 8022 // Convert the arguments. 8023 ExprResult InputInit 8024 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 8025 Context, 8026 FnDecl->getParamDecl(0)), 8027 SourceLocation(), 8028 Input); 8029 if (InputInit.isInvalid()) 8030 return ExprError(); 8031 Input = InputInit.take(); 8032 } 8033 8034 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 8035 8036 // Determine the result type. 8037 QualType ResultTy = FnDecl->getResultType(); 8038 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8039 ResultTy = ResultTy.getNonLValueExprType(Context); 8040 8041 // Build the actual expression node. 8042 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl); 8043 if (FnExpr.isInvalid()) 8044 return ExprError(); 8045 8046 Args[0] = Input; 8047 CallExpr *TheCall = 8048 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 8049 Args, NumArgs, ResultTy, VK, OpLoc); 8050 8051 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 8052 FnDecl)) 8053 return ExprError(); 8054 8055 return MaybeBindToTemporary(TheCall); 8056 } else { 8057 // We matched a built-in operator. Convert the arguments, then 8058 // break out so that we will build the appropriate built-in 8059 // operator node. 8060 ExprResult InputRes = 8061 PerformImplicitConversion(Input, Best->BuiltinTypes.ParamTypes[0], 8062 Best->Conversions[0], AA_Passing); 8063 if (InputRes.isInvalid()) 8064 return ExprError(); 8065 Input = InputRes.take(); 8066 break; 8067 } 8068 } 8069 8070 case OR_No_Viable_Function: 8071 // No viable function; fall through to handling this as a 8072 // built-in operator, which will produce an error message for us. 8073 break; 8074 8075 case OR_Ambiguous: 8076 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 8077 << UnaryOperator::getOpcodeStr(Opc) 8078 << Input->getType() 8079 << Input->getSourceRange(); 8080 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, 8081 Args, NumArgs, 8082 UnaryOperator::getOpcodeStr(Opc), OpLoc); 8083 return ExprError(); 8084 8085 case OR_Deleted: 8086 Diag(OpLoc, diag::err_ovl_deleted_oper) 8087 << Best->Function->isDeleted() 8088 << UnaryOperator::getOpcodeStr(Opc) 8089 << getDeletedOrUnavailableSuffix(Best->Function) 8090 << Input->getSourceRange(); 8091 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8092 return ExprError(); 8093 } 8094 8095 // Either we found no viable overloaded operator or we matched a 8096 // built-in operator. In either case, fall through to trying to 8097 // build a built-in operation. 8098 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8099} 8100 8101/// \brief Create a binary operation that may resolve to an overloaded 8102/// operator. 8103/// 8104/// \param OpLoc The location of the operator itself (e.g., '+'). 8105/// 8106/// \param OpcIn The BinaryOperator::Opcode that describes this 8107/// operator. 8108/// 8109/// \param Functions The set of non-member functions that will be 8110/// considered by overload resolution. The caller needs to build this 8111/// set based on the context using, e.g., 8112/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 8113/// set should not contain any member functions; those will be added 8114/// by CreateOverloadedBinOp(). 8115/// 8116/// \param LHS Left-hand argument. 8117/// \param RHS Right-hand argument. 8118ExprResult 8119Sema::CreateOverloadedBinOp(SourceLocation OpLoc, 8120 unsigned OpcIn, 8121 const UnresolvedSetImpl &Fns, 8122 Expr *LHS, Expr *RHS) { 8123 Expr *Args[2] = { LHS, RHS }; 8124 LHS=RHS=0; //Please use only Args instead of LHS/RHS couple 8125 8126 BinaryOperator::Opcode Opc = static_cast<BinaryOperator::Opcode>(OpcIn); 8127 OverloadedOperatorKind Op = BinaryOperator::getOverloadedOperator(Opc); 8128 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 8129 8130 // If either side is type-dependent, create an appropriate dependent 8131 // expression. 8132 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 8133 if (Fns.empty()) { 8134 // If there are no functions to store, just build a dependent 8135 // BinaryOperator or CompoundAssignment. 8136 if (Opc <= BO_Assign || Opc > BO_OrAssign) 8137 return Owned(new (Context) BinaryOperator(Args[0], Args[1], Opc, 8138 Context.DependentTy, 8139 VK_RValue, OK_Ordinary, 8140 OpLoc)); 8141 8142 return Owned(new (Context) CompoundAssignOperator(Args[0], Args[1], Opc, 8143 Context.DependentTy, 8144 VK_LValue, 8145 OK_Ordinary, 8146 Context.DependentTy, 8147 Context.DependentTy, 8148 OpLoc)); 8149 } 8150 8151 // FIXME: save results of ADL from here? 8152 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8153 // TODO: provide better source location info in DNLoc component. 8154 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 8155 UnresolvedLookupExpr *Fn 8156 = UnresolvedLookupExpr::Create(Context, NamingClass, 8157 NestedNameSpecifierLoc(), OpNameInfo, 8158 /*ADL*/ true, IsOverloaded(Fns), 8159 Fns.begin(), Fns.end()); 8160 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 8161 Args, 2, 8162 Context.DependentTy, 8163 VK_RValue, 8164 OpLoc)); 8165 } 8166 8167 // Always do property rvalue conversions on the RHS. 8168 if (Args[1]->getObjectKind() == OK_ObjCProperty) { 8169 ExprResult Result = ConvertPropertyForRValue(Args[1]); 8170 if (Result.isInvalid()) 8171 return ExprError(); 8172 Args[1] = Result.take(); 8173 } 8174 8175 // The LHS is more complicated. 8176 if (Args[0]->getObjectKind() == OK_ObjCProperty) { 8177 8178 // There's a tension for assignment operators between primitive 8179 // property assignment and the overloaded operators. 8180 if (BinaryOperator::isAssignmentOp(Opc)) { 8181 const ObjCPropertyRefExpr *PRE = LHS->getObjCProperty(); 8182 8183 // Is the property "logically" settable? 8184 bool Settable = (PRE->isExplicitProperty() || 8185 PRE->getImplicitPropertySetter()); 8186 8187 // To avoid gratuitously inventing semantics, use the primitive 8188 // unless it isn't. Thoughts in case we ever really care: 8189 // - If the property isn't logically settable, we have to 8190 // load and hope. 8191 // - If the property is settable and this is simple assignment, 8192 // we really should use the primitive. 8193 // - If the property is settable, then we could try overloading 8194 // on a generic lvalue of the appropriate type; if it works 8195 // out to a builtin candidate, we would do that same operation 8196 // on the property, and otherwise just error. 8197 if (Settable) 8198 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8199 } 8200 8201 ExprResult Result = ConvertPropertyForRValue(Args[0]); 8202 if (Result.isInvalid()) 8203 return ExprError(); 8204 Args[0] = Result.take(); 8205 } 8206 8207 // If this is the assignment operator, we only perform overload resolution 8208 // if the left-hand side is a class or enumeration type. This is actually 8209 // a hack. The standard requires that we do overload resolution between the 8210 // various built-in candidates, but as DR507 points out, this can lead to 8211 // problems. So we do it this way, which pretty much follows what GCC does. 8212 // Note that we go the traditional code path for compound assignment forms. 8213 if (Opc == BO_Assign && !Args[0]->getType()->isOverloadableType()) 8214 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8215 8216 // If this is the .* operator, which is not overloadable, just 8217 // create a built-in binary operator. 8218 if (Opc == BO_PtrMemD) 8219 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8220 8221 // Build an empty overload set. 8222 OverloadCandidateSet CandidateSet(OpLoc); 8223 8224 // Add the candidates from the given function set. 8225 AddFunctionCandidates(Fns, Args, 2, CandidateSet, false); 8226 8227 // Add operator candidates that are member functions. 8228 AddMemberOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 8229 8230 // Add candidates from ADL. 8231 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 8232 Args, 2, 8233 /*ExplicitTemplateArgs*/ 0, 8234 CandidateSet); 8235 8236 // Add builtin operator candidates. 8237 AddBuiltinOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 8238 8239 // Perform overload resolution. 8240 OverloadCandidateSet::iterator Best; 8241 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8242 case OR_Success: { 8243 // We found a built-in operator or an overloaded operator. 8244 FunctionDecl *FnDecl = Best->Function; 8245 8246 if (FnDecl) { 8247 // We matched an overloaded operator. Build a call to that 8248 // operator. 8249 8250 MarkDeclarationReferenced(OpLoc, FnDecl); 8251 8252 // Convert the arguments. 8253 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 8254 // Best->Access is only meaningful for class members. 8255 CheckMemberOperatorAccess(OpLoc, Args[0], Args[1], Best->FoundDecl); 8256 8257 ExprResult Arg1 = 8258 PerformCopyInitialization( 8259 InitializedEntity::InitializeParameter(Context, 8260 FnDecl->getParamDecl(0)), 8261 SourceLocation(), Owned(Args[1])); 8262 if (Arg1.isInvalid()) 8263 return ExprError(); 8264 8265 ExprResult Arg0 = 8266 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 8267 Best->FoundDecl, Method); 8268 if (Arg0.isInvalid()) 8269 return ExprError(); 8270 Args[0] = Arg0.takeAs<Expr>(); 8271 Args[1] = RHS = Arg1.takeAs<Expr>(); 8272 } else { 8273 // Convert the arguments. 8274 ExprResult Arg0 = PerformCopyInitialization( 8275 InitializedEntity::InitializeParameter(Context, 8276 FnDecl->getParamDecl(0)), 8277 SourceLocation(), Owned(Args[0])); 8278 if (Arg0.isInvalid()) 8279 return ExprError(); 8280 8281 ExprResult Arg1 = 8282 PerformCopyInitialization( 8283 InitializedEntity::InitializeParameter(Context, 8284 FnDecl->getParamDecl(1)), 8285 SourceLocation(), Owned(Args[1])); 8286 if (Arg1.isInvalid()) 8287 return ExprError(); 8288 Args[0] = LHS = Arg0.takeAs<Expr>(); 8289 Args[1] = RHS = Arg1.takeAs<Expr>(); 8290 } 8291 8292 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 8293 8294 // Determine the result type. 8295 QualType ResultTy = FnDecl->getResultType(); 8296 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8297 ResultTy = ResultTy.getNonLValueExprType(Context); 8298 8299 // Build the actual expression node. 8300 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, OpLoc); 8301 if (FnExpr.isInvalid()) 8302 return ExprError(); 8303 8304 CXXOperatorCallExpr *TheCall = 8305 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 8306 Args, 2, ResultTy, VK, OpLoc); 8307 8308 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 8309 FnDecl)) 8310 return ExprError(); 8311 8312 return MaybeBindToTemporary(TheCall); 8313 } else { 8314 // We matched a built-in operator. Convert the arguments, then 8315 // break out so that we will build the appropriate built-in 8316 // operator node. 8317 ExprResult ArgsRes0 = 8318 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 8319 Best->Conversions[0], AA_Passing); 8320 if (ArgsRes0.isInvalid()) 8321 return ExprError(); 8322 Args[0] = ArgsRes0.take(); 8323 8324 ExprResult ArgsRes1 = 8325 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 8326 Best->Conversions[1], AA_Passing); 8327 if (ArgsRes1.isInvalid()) 8328 return ExprError(); 8329 Args[1] = ArgsRes1.take(); 8330 break; 8331 } 8332 } 8333 8334 case OR_No_Viable_Function: { 8335 // C++ [over.match.oper]p9: 8336 // If the operator is the operator , [...] and there are no 8337 // viable functions, then the operator is assumed to be the 8338 // built-in operator and interpreted according to clause 5. 8339 if (Opc == BO_Comma) 8340 break; 8341 8342 // For class as left operand for assignment or compound assigment 8343 // operator do not fall through to handling in built-in, but report that 8344 // no overloaded assignment operator found 8345 ExprResult Result = ExprError(); 8346 if (Args[0]->getType()->isRecordType() && 8347 Opc >= BO_Assign && Opc <= BO_OrAssign) { 8348 Diag(OpLoc, diag::err_ovl_no_viable_oper) 8349 << BinaryOperator::getOpcodeStr(Opc) 8350 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8351 } else { 8352 // No viable function; try to create a built-in operation, which will 8353 // produce an error. Then, show the non-viable candidates. 8354 Result = CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8355 } 8356 assert(Result.isInvalid() && 8357 "C++ binary operator overloading is missing candidates!"); 8358 if (Result.isInvalid()) 8359 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8360 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8361 return move(Result); 8362 } 8363 8364 case OR_Ambiguous: 8365 Diag(OpLoc, diag::err_ovl_ambiguous_oper_binary) 8366 << BinaryOperator::getOpcodeStr(Opc) 8367 << Args[0]->getType() << Args[1]->getType() 8368 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8369 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 8370 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8371 return ExprError(); 8372 8373 case OR_Deleted: 8374 Diag(OpLoc, diag::err_ovl_deleted_oper) 8375 << Best->Function->isDeleted() 8376 << BinaryOperator::getOpcodeStr(Opc) 8377 << getDeletedOrUnavailableSuffix(Best->Function) 8378 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8379 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2); 8380 return ExprError(); 8381 } 8382 8383 // We matched a built-in operator; build it. 8384 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8385} 8386 8387ExprResult 8388Sema::CreateOverloadedArraySubscriptExpr(SourceLocation LLoc, 8389 SourceLocation RLoc, 8390 Expr *Base, Expr *Idx) { 8391 Expr *Args[2] = { Base, Idx }; 8392 DeclarationName OpName = 8393 Context.DeclarationNames.getCXXOperatorName(OO_Subscript); 8394 8395 // If either side is type-dependent, create an appropriate dependent 8396 // expression. 8397 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 8398 8399 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8400 // CHECKME: no 'operator' keyword? 8401 DeclarationNameInfo OpNameInfo(OpName, LLoc); 8402 OpNameInfo.setCXXOperatorNameRange(SourceRange(LLoc, RLoc)); 8403 UnresolvedLookupExpr *Fn 8404 = UnresolvedLookupExpr::Create(Context, NamingClass, 8405 NestedNameSpecifierLoc(), OpNameInfo, 8406 /*ADL*/ true, /*Overloaded*/ false, 8407 UnresolvedSetIterator(), 8408 UnresolvedSetIterator()); 8409 // Can't add any actual overloads yet 8410 8411 return Owned(new (Context) CXXOperatorCallExpr(Context, OO_Subscript, Fn, 8412 Args, 2, 8413 Context.DependentTy, 8414 VK_RValue, 8415 RLoc)); 8416 } 8417 8418 if (Args[0]->getObjectKind() == OK_ObjCProperty) { 8419 ExprResult Result = ConvertPropertyForRValue(Args[0]); 8420 if (Result.isInvalid()) 8421 return ExprError(); 8422 Args[0] = Result.take(); 8423 } 8424 if (Args[1]->getObjectKind() == OK_ObjCProperty) { 8425 ExprResult Result = ConvertPropertyForRValue(Args[1]); 8426 if (Result.isInvalid()) 8427 return ExprError(); 8428 Args[1] = Result.take(); 8429 } 8430 8431 // Build an empty overload set. 8432 OverloadCandidateSet CandidateSet(LLoc); 8433 8434 // Subscript can only be overloaded as a member function. 8435 8436 // Add operator candidates that are member functions. 8437 AddMemberOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 8438 8439 // Add builtin operator candidates. 8440 AddBuiltinOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 8441 8442 // Perform overload resolution. 8443 OverloadCandidateSet::iterator Best; 8444 switch (CandidateSet.BestViableFunction(*this, LLoc, Best)) { 8445 case OR_Success: { 8446 // We found a built-in operator or an overloaded operator. 8447 FunctionDecl *FnDecl = Best->Function; 8448 8449 if (FnDecl) { 8450 // We matched an overloaded operator. Build a call to that 8451 // operator. 8452 8453 MarkDeclarationReferenced(LLoc, FnDecl); 8454 8455 CheckMemberOperatorAccess(LLoc, Args[0], Args[1], Best->FoundDecl); 8456 DiagnoseUseOfDecl(Best->FoundDecl, LLoc); 8457 8458 // Convert the arguments. 8459 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 8460 ExprResult Arg0 = 8461 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 8462 Best->FoundDecl, Method); 8463 if (Arg0.isInvalid()) 8464 return ExprError(); 8465 Args[0] = Arg0.take(); 8466 8467 // Convert the arguments. 8468 ExprResult InputInit 8469 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 8470 Context, 8471 FnDecl->getParamDecl(0)), 8472 SourceLocation(), 8473 Owned(Args[1])); 8474 if (InputInit.isInvalid()) 8475 return ExprError(); 8476 8477 Args[1] = InputInit.takeAs<Expr>(); 8478 8479 // Determine the result type 8480 QualType ResultTy = FnDecl->getResultType(); 8481 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8482 ResultTy = ResultTy.getNonLValueExprType(Context); 8483 8484 // Build the actual expression node. 8485 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, LLoc); 8486 if (FnExpr.isInvalid()) 8487 return ExprError(); 8488 8489 CXXOperatorCallExpr *TheCall = 8490 new (Context) CXXOperatorCallExpr(Context, OO_Subscript, 8491 FnExpr.take(), Args, 2, 8492 ResultTy, VK, RLoc); 8493 8494 if (CheckCallReturnType(FnDecl->getResultType(), LLoc, TheCall, 8495 FnDecl)) 8496 return ExprError(); 8497 8498 return MaybeBindToTemporary(TheCall); 8499 } else { 8500 // We matched a built-in operator. Convert the arguments, then 8501 // break out so that we will build the appropriate built-in 8502 // operator node. 8503 ExprResult ArgsRes0 = 8504 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 8505 Best->Conversions[0], AA_Passing); 8506 if (ArgsRes0.isInvalid()) 8507 return ExprError(); 8508 Args[0] = ArgsRes0.take(); 8509 8510 ExprResult ArgsRes1 = 8511 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 8512 Best->Conversions[1], AA_Passing); 8513 if (ArgsRes1.isInvalid()) 8514 return ExprError(); 8515 Args[1] = ArgsRes1.take(); 8516 8517 break; 8518 } 8519 } 8520 8521 case OR_No_Viable_Function: { 8522 if (CandidateSet.empty()) 8523 Diag(LLoc, diag::err_ovl_no_oper) 8524 << Args[0]->getType() << /*subscript*/ 0 8525 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8526 else 8527 Diag(LLoc, diag::err_ovl_no_viable_subscript) 8528 << Args[0]->getType() 8529 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8530 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8531 "[]", LLoc); 8532 return ExprError(); 8533 } 8534 8535 case OR_Ambiguous: 8536 Diag(LLoc, diag::err_ovl_ambiguous_oper_binary) 8537 << "[]" 8538 << Args[0]->getType() << Args[1]->getType() 8539 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8540 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 8541 "[]", LLoc); 8542 return ExprError(); 8543 8544 case OR_Deleted: 8545 Diag(LLoc, diag::err_ovl_deleted_oper) 8546 << Best->Function->isDeleted() << "[]" 8547 << getDeletedOrUnavailableSuffix(Best->Function) 8548 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8549 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8550 "[]", LLoc); 8551 return ExprError(); 8552 } 8553 8554 // We matched a built-in operator; build it. 8555 return CreateBuiltinArraySubscriptExpr(Args[0], LLoc, Args[1], RLoc); 8556} 8557 8558/// BuildCallToMemberFunction - Build a call to a member 8559/// function. MemExpr is the expression that refers to the member 8560/// function (and includes the object parameter), Args/NumArgs are the 8561/// arguments to the function call (not including the object 8562/// parameter). The caller needs to validate that the member 8563/// expression refers to a non-static member function or an overloaded 8564/// member function. 8565ExprResult 8566Sema::BuildCallToMemberFunction(Scope *S, Expr *MemExprE, 8567 SourceLocation LParenLoc, Expr **Args, 8568 unsigned NumArgs, SourceLocation RParenLoc) { 8569 assert(MemExprE->getType() == Context.BoundMemberTy || 8570 MemExprE->getType() == Context.OverloadTy); 8571 8572 // Dig out the member expression. This holds both the object 8573 // argument and the member function we're referring to. 8574 Expr *NakedMemExpr = MemExprE->IgnoreParens(); 8575 8576 // Determine whether this is a call to a pointer-to-member function. 8577 if (BinaryOperator *op = dyn_cast<BinaryOperator>(NakedMemExpr)) { 8578 assert(op->getType() == Context.BoundMemberTy); 8579 assert(op->getOpcode() == BO_PtrMemD || op->getOpcode() == BO_PtrMemI); 8580 8581 QualType fnType = 8582 op->getRHS()->getType()->castAs<MemberPointerType>()->getPointeeType(); 8583 8584 const FunctionProtoType *proto = fnType->castAs<FunctionProtoType>(); 8585 QualType resultType = proto->getCallResultType(Context); 8586 ExprValueKind valueKind = Expr::getValueKindForType(proto->getResultType()); 8587 8588 // Check that the object type isn't more qualified than the 8589 // member function we're calling. 8590 Qualifiers funcQuals = Qualifiers::fromCVRMask(proto->getTypeQuals()); 8591 8592 QualType objectType = op->getLHS()->getType(); 8593 if (op->getOpcode() == BO_PtrMemI) 8594 objectType = objectType->castAs<PointerType>()->getPointeeType(); 8595 Qualifiers objectQuals = objectType.getQualifiers(); 8596 8597 Qualifiers difference = objectQuals - funcQuals; 8598 difference.removeObjCGCAttr(); 8599 difference.removeAddressSpace(); 8600 if (difference) { 8601 std::string qualsString = difference.getAsString(); 8602 Diag(LParenLoc, diag::err_pointer_to_member_call_drops_quals) 8603 << fnType.getUnqualifiedType() 8604 << qualsString 8605 << (qualsString.find(' ') == std::string::npos ? 1 : 2); 8606 } 8607 8608 CXXMemberCallExpr *call 8609 = new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 8610 resultType, valueKind, RParenLoc); 8611 8612 if (CheckCallReturnType(proto->getResultType(), 8613 op->getRHS()->getSourceRange().getBegin(), 8614 call, 0)) 8615 return ExprError(); 8616 8617 if (ConvertArgumentsForCall(call, op, 0, proto, Args, NumArgs, RParenLoc)) 8618 return ExprError(); 8619 8620 return MaybeBindToTemporary(call); 8621 } 8622 8623 MemberExpr *MemExpr; 8624 CXXMethodDecl *Method = 0; 8625 DeclAccessPair FoundDecl = DeclAccessPair::make(0, AS_public); 8626 NestedNameSpecifier *Qualifier = 0; 8627 if (isa<MemberExpr>(NakedMemExpr)) { 8628 MemExpr = cast<MemberExpr>(NakedMemExpr); 8629 Method = cast<CXXMethodDecl>(MemExpr->getMemberDecl()); 8630 FoundDecl = MemExpr->getFoundDecl(); 8631 Qualifier = MemExpr->getQualifier(); 8632 } else { 8633 UnresolvedMemberExpr *UnresExpr = cast<UnresolvedMemberExpr>(NakedMemExpr); 8634 Qualifier = UnresExpr->getQualifier(); 8635 8636 QualType ObjectType = UnresExpr->getBaseType(); 8637 Expr::Classification ObjectClassification 8638 = UnresExpr->isArrow()? Expr::Classification::makeSimpleLValue() 8639 : UnresExpr->getBase()->Classify(Context); 8640 8641 // Add overload candidates 8642 OverloadCandidateSet CandidateSet(UnresExpr->getMemberLoc()); 8643 8644 // FIXME: avoid copy. 8645 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 8646 if (UnresExpr->hasExplicitTemplateArgs()) { 8647 UnresExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 8648 TemplateArgs = &TemplateArgsBuffer; 8649 } 8650 8651 for (UnresolvedMemberExpr::decls_iterator I = UnresExpr->decls_begin(), 8652 E = UnresExpr->decls_end(); I != E; ++I) { 8653 8654 NamedDecl *Func = *I; 8655 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(Func->getDeclContext()); 8656 if (isa<UsingShadowDecl>(Func)) 8657 Func = cast<UsingShadowDecl>(Func)->getTargetDecl(); 8658 8659 8660 // Microsoft supports direct constructor calls. 8661 if (getLangOptions().Microsoft && isa<CXXConstructorDecl>(Func)) { 8662 AddOverloadCandidate(cast<CXXConstructorDecl>(Func), I.getPair(), Args, NumArgs, 8663 CandidateSet); 8664 } else if ((Method = dyn_cast<CXXMethodDecl>(Func))) { 8665 // If explicit template arguments were provided, we can't call a 8666 // non-template member function. 8667 if (TemplateArgs) 8668 continue; 8669 8670 AddMethodCandidate(Method, I.getPair(), ActingDC, ObjectType, 8671 ObjectClassification, 8672 Args, NumArgs, CandidateSet, 8673 /*SuppressUserConversions=*/false); 8674 } else { 8675 AddMethodTemplateCandidate(cast<FunctionTemplateDecl>(Func), 8676 I.getPair(), ActingDC, TemplateArgs, 8677 ObjectType, ObjectClassification, 8678 Args, NumArgs, CandidateSet, 8679 /*SuppressUsedConversions=*/false); 8680 } 8681 } 8682 8683 DeclarationName DeclName = UnresExpr->getMemberName(); 8684 8685 OverloadCandidateSet::iterator Best; 8686 switch (CandidateSet.BestViableFunction(*this, UnresExpr->getLocStart(), 8687 Best)) { 8688 case OR_Success: 8689 Method = cast<CXXMethodDecl>(Best->Function); 8690 MarkDeclarationReferenced(UnresExpr->getMemberLoc(), Method); 8691 FoundDecl = Best->FoundDecl; 8692 CheckUnresolvedMemberAccess(UnresExpr, Best->FoundDecl); 8693 DiagnoseUseOfDecl(Best->FoundDecl, UnresExpr->getNameLoc()); 8694 break; 8695 8696 case OR_No_Viable_Function: 8697 Diag(UnresExpr->getMemberLoc(), 8698 diag::err_ovl_no_viable_member_function_in_call) 8699 << DeclName << MemExprE->getSourceRange(); 8700 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8701 // FIXME: Leaking incoming expressions! 8702 return ExprError(); 8703 8704 case OR_Ambiguous: 8705 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_ambiguous_member_call) 8706 << DeclName << MemExprE->getSourceRange(); 8707 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8708 // FIXME: Leaking incoming expressions! 8709 return ExprError(); 8710 8711 case OR_Deleted: 8712 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_deleted_member_call) 8713 << Best->Function->isDeleted() 8714 << DeclName 8715 << getDeletedOrUnavailableSuffix(Best->Function) 8716 << MemExprE->getSourceRange(); 8717 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8718 // FIXME: Leaking incoming expressions! 8719 return ExprError(); 8720 } 8721 8722 MemExprE = FixOverloadedFunctionReference(MemExprE, FoundDecl, Method); 8723 8724 // If overload resolution picked a static member, build a 8725 // non-member call based on that function. 8726 if (Method->isStatic()) { 8727 return BuildResolvedCallExpr(MemExprE, Method, LParenLoc, 8728 Args, NumArgs, RParenLoc); 8729 } 8730 8731 MemExpr = cast<MemberExpr>(MemExprE->IgnoreParens()); 8732 } 8733 8734 QualType ResultType = Method->getResultType(); 8735 ExprValueKind VK = Expr::getValueKindForType(ResultType); 8736 ResultType = ResultType.getNonLValueExprType(Context); 8737 8738 assert(Method && "Member call to something that isn't a method?"); 8739 CXXMemberCallExpr *TheCall = 8740 new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 8741 ResultType, VK, RParenLoc); 8742 8743 // Check for a valid return type. 8744 if (CheckCallReturnType(Method->getResultType(), MemExpr->getMemberLoc(), 8745 TheCall, Method)) 8746 return ExprError(); 8747 8748 // Convert the object argument (for a non-static member function call). 8749 // We only need to do this if there was actually an overload; otherwise 8750 // it was done at lookup. 8751 if (!Method->isStatic()) { 8752 ExprResult ObjectArg = 8753 PerformObjectArgumentInitialization(MemExpr->getBase(), Qualifier, 8754 FoundDecl, Method); 8755 if (ObjectArg.isInvalid()) 8756 return ExprError(); 8757 MemExpr->setBase(ObjectArg.take()); 8758 } 8759 8760 // Convert the rest of the arguments 8761 const FunctionProtoType *Proto = 8762 Method->getType()->getAs<FunctionProtoType>(); 8763 if (ConvertArgumentsForCall(TheCall, MemExpr, Method, Proto, Args, NumArgs, 8764 RParenLoc)) 8765 return ExprError(); 8766 8767 if (CheckFunctionCall(Method, TheCall)) 8768 return ExprError(); 8769 8770 return MaybeBindToTemporary(TheCall); 8771} 8772 8773/// BuildCallToObjectOfClassType - Build a call to an object of class 8774/// type (C++ [over.call.object]), which can end up invoking an 8775/// overloaded function call operator (@c operator()) or performing a 8776/// user-defined conversion on the object argument. 8777ExprResult 8778Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj, 8779 SourceLocation LParenLoc, 8780 Expr **Args, unsigned NumArgs, 8781 SourceLocation RParenLoc) { 8782 ExprResult Object = Owned(Obj); 8783 if (Object.get()->getObjectKind() == OK_ObjCProperty) { 8784 Object = ConvertPropertyForRValue(Object.take()); 8785 if (Object.isInvalid()) 8786 return ExprError(); 8787 } 8788 8789 assert(Object.get()->getType()->isRecordType() && "Requires object type argument"); 8790 const RecordType *Record = Object.get()->getType()->getAs<RecordType>(); 8791 8792 // C++ [over.call.object]p1: 8793 // If the primary-expression E in the function call syntax 8794 // evaluates to a class object of type "cv T", then the set of 8795 // candidate functions includes at least the function call 8796 // operators of T. The function call operators of T are obtained by 8797 // ordinary lookup of the name operator() in the context of 8798 // (E).operator(). 8799 OverloadCandidateSet CandidateSet(LParenLoc); 8800 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(OO_Call); 8801 8802 if (RequireCompleteType(LParenLoc, Object.get()->getType(), 8803 PDiag(diag::err_incomplete_object_call) 8804 << Object.get()->getSourceRange())) 8805 return true; 8806 8807 LookupResult R(*this, OpName, LParenLoc, LookupOrdinaryName); 8808 LookupQualifiedName(R, Record->getDecl()); 8809 R.suppressDiagnostics(); 8810 8811 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 8812 Oper != OperEnd; ++Oper) { 8813 AddMethodCandidate(Oper.getPair(), Object.get()->getType(), 8814 Object.get()->Classify(Context), Args, NumArgs, CandidateSet, 8815 /*SuppressUserConversions=*/ false); 8816 } 8817 8818 // C++ [over.call.object]p2: 8819 // In addition, for each conversion function declared in T of the 8820 // form 8821 // 8822 // operator conversion-type-id () cv-qualifier; 8823 // 8824 // where cv-qualifier is the same cv-qualification as, or a 8825 // greater cv-qualification than, cv, and where conversion-type-id 8826 // denotes the type "pointer to function of (P1,...,Pn) returning 8827 // R", or the type "reference to pointer to function of 8828 // (P1,...,Pn) returning R", or the type "reference to function 8829 // of (P1,...,Pn) returning R", a surrogate call function [...] 8830 // is also considered as a candidate function. Similarly, 8831 // surrogate call functions are added to the set of candidate 8832 // functions for each conversion function declared in an 8833 // accessible base class provided the function is not hidden 8834 // within T by another intervening declaration. 8835 const UnresolvedSetImpl *Conversions 8836 = cast<CXXRecordDecl>(Record->getDecl())->getVisibleConversionFunctions(); 8837 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 8838 E = Conversions->end(); I != E; ++I) { 8839 NamedDecl *D = *I; 8840 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 8841 if (isa<UsingShadowDecl>(D)) 8842 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 8843 8844 // Skip over templated conversion functions; they aren't 8845 // surrogates. 8846 if (isa<FunctionTemplateDecl>(D)) 8847 continue; 8848 8849 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 8850 8851 // Strip the reference type (if any) and then the pointer type (if 8852 // any) to get down to what might be a function type. 8853 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 8854 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 8855 ConvType = ConvPtrType->getPointeeType(); 8856 8857 if (const FunctionProtoType *Proto = ConvType->getAs<FunctionProtoType>()) 8858 AddSurrogateCandidate(Conv, I.getPair(), ActingContext, Proto, 8859 Object.get(), Args, NumArgs, CandidateSet); 8860 } 8861 8862 // Perform overload resolution. 8863 OverloadCandidateSet::iterator Best; 8864 switch (CandidateSet.BestViableFunction(*this, Object.get()->getLocStart(), 8865 Best)) { 8866 case OR_Success: 8867 // Overload resolution succeeded; we'll build the appropriate call 8868 // below. 8869 break; 8870 8871 case OR_No_Viable_Function: 8872 if (CandidateSet.empty()) 8873 Diag(Object.get()->getSourceRange().getBegin(), diag::err_ovl_no_oper) 8874 << Object.get()->getType() << /*call*/ 1 8875 << Object.get()->getSourceRange(); 8876 else 8877 Diag(Object.get()->getSourceRange().getBegin(), 8878 diag::err_ovl_no_viable_object_call) 8879 << Object.get()->getType() << Object.get()->getSourceRange(); 8880 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8881 break; 8882 8883 case OR_Ambiguous: 8884 Diag(Object.get()->getSourceRange().getBegin(), 8885 diag::err_ovl_ambiguous_object_call) 8886 << Object.get()->getType() << Object.get()->getSourceRange(); 8887 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 8888 break; 8889 8890 case OR_Deleted: 8891 Diag(Object.get()->getSourceRange().getBegin(), 8892 diag::err_ovl_deleted_object_call) 8893 << Best->Function->isDeleted() 8894 << Object.get()->getType() 8895 << getDeletedOrUnavailableSuffix(Best->Function) 8896 << Object.get()->getSourceRange(); 8897 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8898 break; 8899 } 8900 8901 if (Best == CandidateSet.end()) 8902 return true; 8903 8904 if (Best->Function == 0) { 8905 // Since there is no function declaration, this is one of the 8906 // surrogate candidates. Dig out the conversion function. 8907 CXXConversionDecl *Conv 8908 = cast<CXXConversionDecl>( 8909 Best->Conversions[0].UserDefined.ConversionFunction); 8910 8911 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 8912 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 8913 8914 // We selected one of the surrogate functions that converts the 8915 // object parameter to a function pointer. Perform the conversion 8916 // on the object argument, then let ActOnCallExpr finish the job. 8917 8918 // Create an implicit member expr to refer to the conversion operator. 8919 // and then call it. 8920 ExprResult Call = BuildCXXMemberCallExpr(Object.get(), Best->FoundDecl, Conv); 8921 if (Call.isInvalid()) 8922 return ExprError(); 8923 8924 return ActOnCallExpr(S, Call.get(), LParenLoc, MultiExprArg(Args, NumArgs), 8925 RParenLoc); 8926 } 8927 8928 MarkDeclarationReferenced(LParenLoc, Best->Function); 8929 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 8930 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 8931 8932 // We found an overloaded operator(). Build a CXXOperatorCallExpr 8933 // that calls this method, using Object for the implicit object 8934 // parameter and passing along the remaining arguments. 8935 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 8936 const FunctionProtoType *Proto = 8937 Method->getType()->getAs<FunctionProtoType>(); 8938 8939 unsigned NumArgsInProto = Proto->getNumArgs(); 8940 unsigned NumArgsToCheck = NumArgs; 8941 8942 // Build the full argument list for the method call (the 8943 // implicit object parameter is placed at the beginning of the 8944 // list). 8945 Expr **MethodArgs; 8946 if (NumArgs < NumArgsInProto) { 8947 NumArgsToCheck = NumArgsInProto; 8948 MethodArgs = new Expr*[NumArgsInProto + 1]; 8949 } else { 8950 MethodArgs = new Expr*[NumArgs + 1]; 8951 } 8952 MethodArgs[0] = Object.get(); 8953 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 8954 MethodArgs[ArgIdx + 1] = Args[ArgIdx]; 8955 8956 ExprResult NewFn = CreateFunctionRefExpr(*this, Method); 8957 if (NewFn.isInvalid()) 8958 return true; 8959 8960 // Once we've built TheCall, all of the expressions are properly 8961 // owned. 8962 QualType ResultTy = Method->getResultType(); 8963 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8964 ResultTy = ResultTy.getNonLValueExprType(Context); 8965 8966 CXXOperatorCallExpr *TheCall = 8967 new (Context) CXXOperatorCallExpr(Context, OO_Call, NewFn.take(), 8968 MethodArgs, NumArgs + 1, 8969 ResultTy, VK, RParenLoc); 8970 delete [] MethodArgs; 8971 8972 if (CheckCallReturnType(Method->getResultType(), LParenLoc, TheCall, 8973 Method)) 8974 return true; 8975 8976 // We may have default arguments. If so, we need to allocate more 8977 // slots in the call for them. 8978 if (NumArgs < NumArgsInProto) 8979 TheCall->setNumArgs(Context, NumArgsInProto + 1); 8980 else if (NumArgs > NumArgsInProto) 8981 NumArgsToCheck = NumArgsInProto; 8982 8983 bool IsError = false; 8984 8985 // Initialize the implicit object parameter. 8986 ExprResult ObjRes = 8987 PerformObjectArgumentInitialization(Object.get(), /*Qualifier=*/0, 8988 Best->FoundDecl, Method); 8989 if (ObjRes.isInvalid()) 8990 IsError = true; 8991 else 8992 Object = move(ObjRes); 8993 TheCall->setArg(0, Object.take()); 8994 8995 // Check the argument types. 8996 for (unsigned i = 0; i != NumArgsToCheck; i++) { 8997 Expr *Arg; 8998 if (i < NumArgs) { 8999 Arg = Args[i]; 9000 9001 // Pass the argument. 9002 9003 ExprResult InputInit 9004 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 9005 Context, 9006 Method->getParamDecl(i)), 9007 SourceLocation(), Arg); 9008 9009 IsError |= InputInit.isInvalid(); 9010 Arg = InputInit.takeAs<Expr>(); 9011 } else { 9012 ExprResult DefArg 9013 = BuildCXXDefaultArgExpr(LParenLoc, Method, Method->getParamDecl(i)); 9014 if (DefArg.isInvalid()) { 9015 IsError = true; 9016 break; 9017 } 9018 9019 Arg = DefArg.takeAs<Expr>(); 9020 } 9021 9022 TheCall->setArg(i + 1, Arg); 9023 } 9024 9025 // If this is a variadic call, handle args passed through "...". 9026 if (Proto->isVariadic()) { 9027 // Promote the arguments (C99 6.5.2.2p7). 9028 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 9029 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], VariadicMethod, 0); 9030 IsError |= Arg.isInvalid(); 9031 TheCall->setArg(i + 1, Arg.take()); 9032 } 9033 } 9034 9035 if (IsError) return true; 9036 9037 if (CheckFunctionCall(Method, TheCall)) 9038 return true; 9039 9040 return MaybeBindToTemporary(TheCall); 9041} 9042 9043/// BuildOverloadedArrowExpr - Build a call to an overloaded @c operator-> 9044/// (if one exists), where @c Base is an expression of class type and 9045/// @c Member is the name of the member we're trying to find. 9046ExprResult 9047Sema::BuildOverloadedArrowExpr(Scope *S, Expr *Base, SourceLocation OpLoc) { 9048 assert(Base->getType()->isRecordType() && 9049 "left-hand side must have class type"); 9050 9051 if (Base->getObjectKind() == OK_ObjCProperty) { 9052 ExprResult Result = ConvertPropertyForRValue(Base); 9053 if (Result.isInvalid()) 9054 return ExprError(); 9055 Base = Result.take(); 9056 } 9057 9058 SourceLocation Loc = Base->getExprLoc(); 9059 9060 // C++ [over.ref]p1: 9061 // 9062 // [...] An expression x->m is interpreted as (x.operator->())->m 9063 // for a class object x of type T if T::operator->() exists and if 9064 // the operator is selected as the best match function by the 9065 // overload resolution mechanism (13.3). 9066 DeclarationName OpName = 9067 Context.DeclarationNames.getCXXOperatorName(OO_Arrow); 9068 OverloadCandidateSet CandidateSet(Loc); 9069 const RecordType *BaseRecord = Base->getType()->getAs<RecordType>(); 9070 9071 if (RequireCompleteType(Loc, Base->getType(), 9072 PDiag(diag::err_typecheck_incomplete_tag) 9073 << Base->getSourceRange())) 9074 return ExprError(); 9075 9076 LookupResult R(*this, OpName, OpLoc, LookupOrdinaryName); 9077 LookupQualifiedName(R, BaseRecord->getDecl()); 9078 R.suppressDiagnostics(); 9079 9080 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 9081 Oper != OperEnd; ++Oper) { 9082 AddMethodCandidate(Oper.getPair(), Base->getType(), Base->Classify(Context), 9083 0, 0, CandidateSet, /*SuppressUserConversions=*/false); 9084 } 9085 9086 // Perform overload resolution. 9087 OverloadCandidateSet::iterator Best; 9088 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 9089 case OR_Success: 9090 // Overload resolution succeeded; we'll build the call below. 9091 break; 9092 9093 case OR_No_Viable_Function: 9094 if (CandidateSet.empty()) 9095 Diag(OpLoc, diag::err_typecheck_member_reference_arrow) 9096 << Base->getType() << Base->getSourceRange(); 9097 else 9098 Diag(OpLoc, diag::err_ovl_no_viable_oper) 9099 << "operator->" << Base->getSourceRange(); 9100 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 9101 return ExprError(); 9102 9103 case OR_Ambiguous: 9104 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 9105 << "->" << Base->getType() << Base->getSourceRange(); 9106 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, &Base, 1); 9107 return ExprError(); 9108 9109 case OR_Deleted: 9110 Diag(OpLoc, diag::err_ovl_deleted_oper) 9111 << Best->Function->isDeleted() 9112 << "->" 9113 << getDeletedOrUnavailableSuffix(Best->Function) 9114 << Base->getSourceRange(); 9115 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 9116 return ExprError(); 9117 } 9118 9119 MarkDeclarationReferenced(OpLoc, Best->Function); 9120 CheckMemberOperatorAccess(OpLoc, Base, 0, Best->FoundDecl); 9121 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 9122 9123 // Convert the object parameter. 9124 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 9125 ExprResult BaseResult = 9126 PerformObjectArgumentInitialization(Base, /*Qualifier=*/0, 9127 Best->FoundDecl, Method); 9128 if (BaseResult.isInvalid()) 9129 return ExprError(); 9130 Base = BaseResult.take(); 9131 9132 // Build the operator call. 9133 ExprResult FnExpr = CreateFunctionRefExpr(*this, Method); 9134 if (FnExpr.isInvalid()) 9135 return ExprError(); 9136 9137 QualType ResultTy = Method->getResultType(); 9138 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9139 ResultTy = ResultTy.getNonLValueExprType(Context); 9140 CXXOperatorCallExpr *TheCall = 9141 new (Context) CXXOperatorCallExpr(Context, OO_Arrow, FnExpr.take(), 9142 &Base, 1, ResultTy, VK, OpLoc); 9143 9144 if (CheckCallReturnType(Method->getResultType(), OpLoc, TheCall, 9145 Method)) 9146 return ExprError(); 9147 9148 return MaybeBindToTemporary(TheCall); 9149} 9150 9151/// FixOverloadedFunctionReference - E is an expression that refers to 9152/// a C++ overloaded function (possibly with some parentheses and 9153/// perhaps a '&' around it). We have resolved the overloaded function 9154/// to the function declaration Fn, so patch up the expression E to 9155/// refer (possibly indirectly) to Fn. Returns the new expr. 9156Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found, 9157 FunctionDecl *Fn) { 9158 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 9159 Expr *SubExpr = FixOverloadedFunctionReference(PE->getSubExpr(), 9160 Found, Fn); 9161 if (SubExpr == PE->getSubExpr()) 9162 return PE; 9163 9164 return new (Context) ParenExpr(PE->getLParen(), PE->getRParen(), SubExpr); 9165 } 9166 9167 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 9168 Expr *SubExpr = FixOverloadedFunctionReference(ICE->getSubExpr(), 9169 Found, Fn); 9170 assert(Context.hasSameType(ICE->getSubExpr()->getType(), 9171 SubExpr->getType()) && 9172 "Implicit cast type cannot be determined from overload"); 9173 assert(ICE->path_empty() && "fixing up hierarchy conversion?"); 9174 if (SubExpr == ICE->getSubExpr()) 9175 return ICE; 9176 9177 return ImplicitCastExpr::Create(Context, ICE->getType(), 9178 ICE->getCastKind(), 9179 SubExpr, 0, 9180 ICE->getValueKind()); 9181 } 9182 9183 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(E)) { 9184 assert(UnOp->getOpcode() == UO_AddrOf && 9185 "Can only take the address of an overloaded function"); 9186 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 9187 if (Method->isStatic()) { 9188 // Do nothing: static member functions aren't any different 9189 // from non-member functions. 9190 } else { 9191 // Fix the sub expression, which really has to be an 9192 // UnresolvedLookupExpr holding an overloaded member function 9193 // or template. 9194 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 9195 Found, Fn); 9196 if (SubExpr == UnOp->getSubExpr()) 9197 return UnOp; 9198 9199 assert(isa<DeclRefExpr>(SubExpr) 9200 && "fixed to something other than a decl ref"); 9201 assert(cast<DeclRefExpr>(SubExpr)->getQualifier() 9202 && "fixed to a member ref with no nested name qualifier"); 9203 9204 // We have taken the address of a pointer to member 9205 // function. Perform the computation here so that we get the 9206 // appropriate pointer to member type. 9207 QualType ClassType 9208 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 9209 QualType MemPtrType 9210 = Context.getMemberPointerType(Fn->getType(), ClassType.getTypePtr()); 9211 9212 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, MemPtrType, 9213 VK_RValue, OK_Ordinary, 9214 UnOp->getOperatorLoc()); 9215 } 9216 } 9217 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 9218 Found, Fn); 9219 if (SubExpr == UnOp->getSubExpr()) 9220 return UnOp; 9221 9222 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, 9223 Context.getPointerType(SubExpr->getType()), 9224 VK_RValue, OK_Ordinary, 9225 UnOp->getOperatorLoc()); 9226 } 9227 9228 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { 9229 // FIXME: avoid copy. 9230 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9231 if (ULE->hasExplicitTemplateArgs()) { 9232 ULE->copyTemplateArgumentsInto(TemplateArgsBuffer); 9233 TemplateArgs = &TemplateArgsBuffer; 9234 } 9235 9236 return DeclRefExpr::Create(Context, 9237 ULE->getQualifierLoc(), 9238 Fn, 9239 ULE->getNameLoc(), 9240 Fn->getType(), 9241 VK_LValue, 9242 TemplateArgs); 9243 } 9244 9245 if (UnresolvedMemberExpr *MemExpr = dyn_cast<UnresolvedMemberExpr>(E)) { 9246 // FIXME: avoid copy. 9247 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9248 if (MemExpr->hasExplicitTemplateArgs()) { 9249 MemExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 9250 TemplateArgs = &TemplateArgsBuffer; 9251 } 9252 9253 Expr *Base; 9254 9255 // If we're filling in a static method where we used to have an 9256 // implicit member access, rewrite to a simple decl ref. 9257 if (MemExpr->isImplicitAccess()) { 9258 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 9259 return DeclRefExpr::Create(Context, 9260 MemExpr->getQualifierLoc(), 9261 Fn, 9262 MemExpr->getMemberLoc(), 9263 Fn->getType(), 9264 VK_LValue, 9265 TemplateArgs); 9266 } else { 9267 SourceLocation Loc = MemExpr->getMemberLoc(); 9268 if (MemExpr->getQualifier()) 9269 Loc = MemExpr->getQualifierLoc().getBeginLoc(); 9270 Base = new (Context) CXXThisExpr(Loc, 9271 MemExpr->getBaseType(), 9272 /*isImplicit=*/true); 9273 } 9274 } else 9275 Base = MemExpr->getBase(); 9276 9277 ExprValueKind valueKind; 9278 QualType type; 9279 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 9280 valueKind = VK_LValue; 9281 type = Fn->getType(); 9282 } else { 9283 valueKind = VK_RValue; 9284 type = Context.BoundMemberTy; 9285 } 9286 9287 return MemberExpr::Create(Context, Base, 9288 MemExpr->isArrow(), 9289 MemExpr->getQualifierLoc(), 9290 Fn, 9291 Found, 9292 MemExpr->getMemberNameInfo(), 9293 TemplateArgs, 9294 type, valueKind, OK_Ordinary); 9295 } 9296 9297 llvm_unreachable("Invalid reference to overloaded function"); 9298 return E; 9299} 9300 9301ExprResult Sema::FixOverloadedFunctionReference(ExprResult E, 9302 DeclAccessPair Found, 9303 FunctionDecl *Fn) { 9304 return Owned(FixOverloadedFunctionReference((Expr *)E.get(), Found, Fn)); 9305} 9306 9307} // end namespace clang 9308