SemaOverload.cpp revision 3aa8140bde5b9bedf13e46ec0a668daa54814196
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 // 3075 // Note that we also require equivalence of Objective-C GC and address-space 3076 // qualifiers when performing these computations, so that e.g., an int in 3077 // address space 1 is not reference-compatible with an int in address 3078 // space 2. 3079 if (T1Quals == T2Quals) 3080 return Ref_Compatible; 3081 else if (T1.isMoreQualifiedThan(T2)) 3082 return Ref_Compatible_With_Added_Qualification; 3083 else 3084 return Ref_Related; 3085} 3086 3087/// \brief Look for a user-defined conversion to an value reference-compatible 3088/// with DeclType. Return true if something definite is found. 3089static bool 3090FindConversionForRefInit(Sema &S, ImplicitConversionSequence &ICS, 3091 QualType DeclType, SourceLocation DeclLoc, 3092 Expr *Init, QualType T2, bool AllowRvalues, 3093 bool AllowExplicit) { 3094 assert(T2->isRecordType() && "Can only find conversions of record types."); 3095 CXXRecordDecl *T2RecordDecl 3096 = dyn_cast<CXXRecordDecl>(T2->getAs<RecordType>()->getDecl()); 3097 3098 OverloadCandidateSet CandidateSet(DeclLoc); 3099 const UnresolvedSetImpl *Conversions 3100 = T2RecordDecl->getVisibleConversionFunctions(); 3101 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 3102 E = Conversions->end(); I != E; ++I) { 3103 NamedDecl *D = *I; 3104 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(D->getDeclContext()); 3105 if (isa<UsingShadowDecl>(D)) 3106 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 3107 3108 FunctionTemplateDecl *ConvTemplate 3109 = dyn_cast<FunctionTemplateDecl>(D); 3110 CXXConversionDecl *Conv; 3111 if (ConvTemplate) 3112 Conv = cast<CXXConversionDecl>(ConvTemplate->getTemplatedDecl()); 3113 else 3114 Conv = cast<CXXConversionDecl>(D); 3115 3116 // If this is an explicit conversion, and we're not allowed to consider 3117 // explicit conversions, skip it. 3118 if (!AllowExplicit && Conv->isExplicit()) 3119 continue; 3120 3121 if (AllowRvalues) { 3122 bool DerivedToBase = false; 3123 bool ObjCConversion = false; 3124 if (!ConvTemplate && 3125 S.CompareReferenceRelationship( 3126 DeclLoc, 3127 Conv->getConversionType().getNonReferenceType() 3128 .getUnqualifiedType(), 3129 DeclType.getNonReferenceType().getUnqualifiedType(), 3130 DerivedToBase, ObjCConversion) == 3131 Sema::Ref_Incompatible) 3132 continue; 3133 } else { 3134 // If the conversion function doesn't return a reference type, 3135 // it can't be considered for this conversion. An rvalue reference 3136 // is only acceptable if its referencee is a function type. 3137 3138 const ReferenceType *RefType = 3139 Conv->getConversionType()->getAs<ReferenceType>(); 3140 if (!RefType || 3141 (!RefType->isLValueReferenceType() && 3142 !RefType->getPointeeType()->isFunctionType())) 3143 continue; 3144 } 3145 3146 if (ConvTemplate) 3147 S.AddTemplateConversionCandidate(ConvTemplate, I.getPair(), ActingDC, 3148 Init, DeclType, CandidateSet); 3149 else 3150 S.AddConversionCandidate(Conv, I.getPair(), ActingDC, Init, 3151 DeclType, CandidateSet); 3152 } 3153 3154 OverloadCandidateSet::iterator Best; 3155 switch (CandidateSet.BestViableFunction(S, DeclLoc, Best, true)) { 3156 case OR_Success: 3157 // C++ [over.ics.ref]p1: 3158 // 3159 // [...] If the parameter binds directly to the result of 3160 // applying a conversion function to the argument 3161 // expression, the implicit conversion sequence is a 3162 // user-defined conversion sequence (13.3.3.1.2), with the 3163 // second standard conversion sequence either an identity 3164 // conversion or, if the conversion function returns an 3165 // entity of a type that is a derived class of the parameter 3166 // type, a derived-to-base Conversion. 3167 if (!Best->FinalConversion.DirectBinding) 3168 return false; 3169 3170 if (Best->Function) 3171 S.MarkDeclarationReferenced(DeclLoc, Best->Function); 3172 ICS.setUserDefined(); 3173 ICS.UserDefined.Before = Best->Conversions[0].Standard; 3174 ICS.UserDefined.After = Best->FinalConversion; 3175 ICS.UserDefined.ConversionFunction = Best->Function; 3176 ICS.UserDefined.FoundConversionFunction = Best->FoundDecl.getDecl(); 3177 ICS.UserDefined.EllipsisConversion = false; 3178 assert(ICS.UserDefined.After.ReferenceBinding && 3179 ICS.UserDefined.After.DirectBinding && 3180 "Expected a direct reference binding!"); 3181 return true; 3182 3183 case OR_Ambiguous: 3184 ICS.setAmbiguous(); 3185 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(); 3186 Cand != CandidateSet.end(); ++Cand) 3187 if (Cand->Viable) 3188 ICS.Ambiguous.addConversion(Cand->Function); 3189 return true; 3190 3191 case OR_No_Viable_Function: 3192 case OR_Deleted: 3193 // There was no suitable conversion, or we found a deleted 3194 // conversion; continue with other checks. 3195 return false; 3196 } 3197 3198 return false; 3199} 3200 3201/// \brief Compute an implicit conversion sequence for reference 3202/// initialization. 3203static ImplicitConversionSequence 3204TryReferenceInit(Sema &S, Expr *&Init, QualType DeclType, 3205 SourceLocation DeclLoc, 3206 bool SuppressUserConversions, 3207 bool AllowExplicit) { 3208 assert(DeclType->isReferenceType() && "Reference init needs a reference"); 3209 3210 // Most paths end in a failed conversion. 3211 ImplicitConversionSequence ICS; 3212 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3213 3214 QualType T1 = DeclType->getAs<ReferenceType>()->getPointeeType(); 3215 QualType T2 = Init->getType(); 3216 3217 // If the initializer is the address of an overloaded function, try 3218 // to resolve the overloaded function. If all goes well, T2 is the 3219 // type of the resulting function. 3220 if (S.Context.getCanonicalType(T2) == S.Context.OverloadTy) { 3221 DeclAccessPair Found; 3222 if (FunctionDecl *Fn = S.ResolveAddressOfOverloadedFunction(Init, DeclType, 3223 false, Found)) 3224 T2 = Fn->getType(); 3225 } 3226 3227 // Compute some basic properties of the types and the initializer. 3228 bool isRValRef = DeclType->isRValueReferenceType(); 3229 bool DerivedToBase = false; 3230 bool ObjCConversion = false; 3231 Expr::Classification InitCategory = Init->Classify(S.Context); 3232 Sema::ReferenceCompareResult RefRelationship 3233 = S.CompareReferenceRelationship(DeclLoc, T1, T2, DerivedToBase, 3234 ObjCConversion); 3235 3236 3237 // C++0x [dcl.init.ref]p5: 3238 // A reference to type "cv1 T1" is initialized by an expression 3239 // of type "cv2 T2" as follows: 3240 3241 // -- If reference is an lvalue reference and the initializer expression 3242 if (!isRValRef) { 3243 // -- is an lvalue (but is not a bit-field), and "cv1 T1" is 3244 // reference-compatible with "cv2 T2," or 3245 // 3246 // Per C++ [over.ics.ref]p4, we don't check the bit-field property here. 3247 if (InitCategory.isLValue() && 3248 RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification) { 3249 // C++ [over.ics.ref]p1: 3250 // When a parameter of reference type binds directly (8.5.3) 3251 // to an argument expression, the implicit conversion sequence 3252 // is the identity conversion, unless the argument expression 3253 // has a type that is a derived class of the parameter type, 3254 // in which case the implicit conversion sequence is a 3255 // derived-to-base Conversion (13.3.3.1). 3256 ICS.setStandard(); 3257 ICS.Standard.First = ICK_Identity; 3258 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3259 : ObjCConversion? ICK_Compatible_Conversion 3260 : ICK_Identity; 3261 ICS.Standard.Third = ICK_Identity; 3262 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3263 ICS.Standard.setToType(0, T2); 3264 ICS.Standard.setToType(1, T1); 3265 ICS.Standard.setToType(2, T1); 3266 ICS.Standard.ReferenceBinding = true; 3267 ICS.Standard.DirectBinding = true; 3268 ICS.Standard.IsLvalueReference = !isRValRef; 3269 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3270 ICS.Standard.BindsToRvalue = false; 3271 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3272 ICS.Standard.CopyConstructor = 0; 3273 3274 // Nothing more to do: the inaccessibility/ambiguity check for 3275 // derived-to-base conversions is suppressed when we're 3276 // computing the implicit conversion sequence (C++ 3277 // [over.best.ics]p2). 3278 return ICS; 3279 } 3280 3281 // -- has a class type (i.e., T2 is a class type), where T1 is 3282 // not reference-related to T2, and can be implicitly 3283 // converted to an lvalue of type "cv3 T3," where "cv1 T1" 3284 // is reference-compatible with "cv3 T3" 92) (this 3285 // conversion is selected by enumerating the applicable 3286 // conversion functions (13.3.1.6) and choosing the best 3287 // one through overload resolution (13.3)), 3288 if (!SuppressUserConversions && T2->isRecordType() && 3289 !S.RequireCompleteType(DeclLoc, T2, 0) && 3290 RefRelationship == Sema::Ref_Incompatible) { 3291 if (FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3292 Init, T2, /*AllowRvalues=*/false, 3293 AllowExplicit)) 3294 return ICS; 3295 } 3296 } 3297 3298 // -- Otherwise, the reference shall be an lvalue reference to a 3299 // non-volatile const type (i.e., cv1 shall be const), or the reference 3300 // shall be an rvalue reference. 3301 // 3302 // We actually handle one oddity of C++ [over.ics.ref] at this 3303 // point, which is that, due to p2 (which short-circuits reference 3304 // binding by only attempting a simple conversion for non-direct 3305 // bindings) and p3's strange wording, we allow a const volatile 3306 // reference to bind to an rvalue. Hence the check for the presence 3307 // of "const" rather than checking for "const" being the only 3308 // qualifier. 3309 // This is also the point where rvalue references and lvalue inits no longer 3310 // go together. 3311 if (!isRValRef && !T1.isConstQualified()) 3312 return ICS; 3313 3314 // -- If the initializer expression 3315 // 3316 // -- is an xvalue, class prvalue, array prvalue or function 3317 // lvalue and "cv1T1" is reference-compatible with "cv2 T2", or 3318 if (RefRelationship >= Sema::Ref_Compatible_With_Added_Qualification && 3319 (InitCategory.isXValue() || 3320 (InitCategory.isPRValue() && (T2->isRecordType() || T2->isArrayType())) || 3321 (InitCategory.isLValue() && T2->isFunctionType()))) { 3322 ICS.setStandard(); 3323 ICS.Standard.First = ICK_Identity; 3324 ICS.Standard.Second = DerivedToBase? ICK_Derived_To_Base 3325 : ObjCConversion? ICK_Compatible_Conversion 3326 : ICK_Identity; 3327 ICS.Standard.Third = ICK_Identity; 3328 ICS.Standard.FromTypePtr = T2.getAsOpaquePtr(); 3329 ICS.Standard.setToType(0, T2); 3330 ICS.Standard.setToType(1, T1); 3331 ICS.Standard.setToType(2, T1); 3332 ICS.Standard.ReferenceBinding = true; 3333 // In C++0x, this is always a direct binding. In C++98/03, it's a direct 3334 // binding unless we're binding to a class prvalue. 3335 // Note: Although xvalues wouldn't normally show up in C++98/03 code, we 3336 // allow the use of rvalue references in C++98/03 for the benefit of 3337 // standard library implementors; therefore, we need the xvalue check here. 3338 ICS.Standard.DirectBinding = 3339 S.getLangOptions().CPlusPlus0x || 3340 (InitCategory.isPRValue() && !T2->isRecordType()); 3341 ICS.Standard.IsLvalueReference = !isRValRef; 3342 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3343 ICS.Standard.BindsToRvalue = InitCategory.isRValue(); 3344 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3345 ICS.Standard.CopyConstructor = 0; 3346 return ICS; 3347 } 3348 3349 // -- has a class type (i.e., T2 is a class type), where T1 is not 3350 // reference-related to T2, and can be implicitly converted to 3351 // an xvalue, class prvalue, or function lvalue of type 3352 // "cv3 T3", where "cv1 T1" is reference-compatible with 3353 // "cv3 T3", 3354 // 3355 // then the reference is bound to the value of the initializer 3356 // expression in the first case and to the result of the conversion 3357 // in the second case (or, in either case, to an appropriate base 3358 // class subobject). 3359 if (!SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3360 T2->isRecordType() && !S.RequireCompleteType(DeclLoc, T2, 0) && 3361 FindConversionForRefInit(S, ICS, DeclType, DeclLoc, 3362 Init, T2, /*AllowRvalues=*/true, 3363 AllowExplicit)) { 3364 // In the second case, if the reference is an rvalue reference 3365 // and the second standard conversion sequence of the 3366 // user-defined conversion sequence includes an lvalue-to-rvalue 3367 // conversion, the program is ill-formed. 3368 if (ICS.isUserDefined() && isRValRef && 3369 ICS.UserDefined.After.First == ICK_Lvalue_To_Rvalue) 3370 ICS.setBad(BadConversionSequence::no_conversion, Init, DeclType); 3371 3372 return ICS; 3373 } 3374 3375 // -- Otherwise, a temporary of type "cv1 T1" is created and 3376 // initialized from the initializer expression using the 3377 // rules for a non-reference copy initialization (8.5). The 3378 // reference is then bound to the temporary. If T1 is 3379 // reference-related to T2, cv1 must be the same 3380 // cv-qualification as, or greater cv-qualification than, 3381 // cv2; otherwise, the program is ill-formed. 3382 if (RefRelationship == Sema::Ref_Related) { 3383 // If cv1 == cv2 or cv1 is a greater cv-qualified than cv2, then 3384 // we would be reference-compatible or reference-compatible with 3385 // added qualification. But that wasn't the case, so the reference 3386 // initialization fails. 3387 return ICS; 3388 } 3389 3390 // If at least one of the types is a class type, the types are not 3391 // related, and we aren't allowed any user conversions, the 3392 // reference binding fails. This case is important for breaking 3393 // recursion, since TryImplicitConversion below will attempt to 3394 // create a temporary through the use of a copy constructor. 3395 if (SuppressUserConversions && RefRelationship == Sema::Ref_Incompatible && 3396 (T1->isRecordType() || T2->isRecordType())) 3397 return ICS; 3398 3399 // If T1 is reference-related to T2 and the reference is an rvalue 3400 // reference, the initializer expression shall not be an lvalue. 3401 if (RefRelationship >= Sema::Ref_Related && 3402 isRValRef && Init->Classify(S.Context).isLValue()) 3403 return ICS; 3404 3405 // C++ [over.ics.ref]p2: 3406 // When a parameter of reference type is not bound directly to 3407 // an argument expression, the conversion sequence is the one 3408 // required to convert the argument expression to the 3409 // underlying type of the reference according to 3410 // 13.3.3.1. Conceptually, this conversion sequence corresponds 3411 // to copy-initializing a temporary of the underlying type with 3412 // the argument expression. Any difference in top-level 3413 // cv-qualification is subsumed by the initialization itself 3414 // and does not constitute a conversion. 3415 ICS = TryImplicitConversion(S, Init, T1, SuppressUserConversions, 3416 /*AllowExplicit=*/false, 3417 /*InOverloadResolution=*/false, 3418 /*CStyle=*/false); 3419 3420 // Of course, that's still a reference binding. 3421 if (ICS.isStandard()) { 3422 ICS.Standard.ReferenceBinding = true; 3423 ICS.Standard.IsLvalueReference = !isRValRef; 3424 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3425 ICS.Standard.BindsToRvalue = true; 3426 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3427 } else if (ICS.isUserDefined()) { 3428 ICS.UserDefined.After.ReferenceBinding = true; 3429 ICS.Standard.IsLvalueReference = !isRValRef; 3430 ICS.Standard.BindsToFunctionLvalue = T2->isFunctionType(); 3431 ICS.Standard.BindsToRvalue = true; 3432 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier = false; 3433 } 3434 3435 return ICS; 3436} 3437 3438/// TryCopyInitialization - Try to copy-initialize a value of type 3439/// ToType from the expression From. Return the implicit conversion 3440/// sequence required to pass this argument, which may be a bad 3441/// conversion sequence (meaning that the argument cannot be passed to 3442/// a parameter of this type). If @p SuppressUserConversions, then we 3443/// do not permit any user-defined conversion sequences. 3444static ImplicitConversionSequence 3445TryCopyInitialization(Sema &S, Expr *From, QualType ToType, 3446 bool SuppressUserConversions, 3447 bool InOverloadResolution) { 3448 if (ToType->isReferenceType()) 3449 return TryReferenceInit(S, From, ToType, 3450 /*FIXME:*/From->getLocStart(), 3451 SuppressUserConversions, 3452 /*AllowExplicit=*/false); 3453 3454 return TryImplicitConversion(S, From, ToType, 3455 SuppressUserConversions, 3456 /*AllowExplicit=*/false, 3457 InOverloadResolution, 3458 /*CStyle=*/false); 3459} 3460 3461/// TryObjectArgumentInitialization - Try to initialize the object 3462/// parameter of the given member function (@c Method) from the 3463/// expression @p From. 3464static ImplicitConversionSequence 3465TryObjectArgumentInitialization(Sema &S, QualType OrigFromType, 3466 Expr::Classification FromClassification, 3467 CXXMethodDecl *Method, 3468 CXXRecordDecl *ActingContext) { 3469 QualType ClassType = S.Context.getTypeDeclType(ActingContext); 3470 // [class.dtor]p2: A destructor can be invoked for a const, volatile or 3471 // const volatile object. 3472 unsigned Quals = isa<CXXDestructorDecl>(Method) ? 3473 Qualifiers::Const | Qualifiers::Volatile : Method->getTypeQualifiers(); 3474 QualType ImplicitParamType = S.Context.getCVRQualifiedType(ClassType, Quals); 3475 3476 // Set up the conversion sequence as a "bad" conversion, to allow us 3477 // to exit early. 3478 ImplicitConversionSequence ICS; 3479 3480 // We need to have an object of class type. 3481 QualType FromType = OrigFromType; 3482 if (const PointerType *PT = FromType->getAs<PointerType>()) { 3483 FromType = PT->getPointeeType(); 3484 3485 // When we had a pointer, it's implicitly dereferenced, so we 3486 // better have an lvalue. 3487 assert(FromClassification.isLValue()); 3488 } 3489 3490 assert(FromType->isRecordType()); 3491 3492 // C++0x [over.match.funcs]p4: 3493 // For non-static member functions, the type of the implicit object 3494 // parameter is 3495 // 3496 // - "lvalue reference to cv X" for functions declared without a 3497 // ref-qualifier or with the & ref-qualifier 3498 // - "rvalue reference to cv X" for functions declared with the && 3499 // ref-qualifier 3500 // 3501 // where X is the class of which the function is a member and cv is the 3502 // cv-qualification on the member function declaration. 3503 // 3504 // However, when finding an implicit conversion sequence for the argument, we 3505 // are not allowed to create temporaries or perform user-defined conversions 3506 // (C++ [over.match.funcs]p5). We perform a simplified version of 3507 // reference binding here, that allows class rvalues to bind to 3508 // non-constant references. 3509 3510 // First check the qualifiers. 3511 QualType FromTypeCanon = S.Context.getCanonicalType(FromType); 3512 if (ImplicitParamType.getCVRQualifiers() 3513 != FromTypeCanon.getLocalCVRQualifiers() && 3514 !ImplicitParamType.isAtLeastAsQualifiedAs(FromTypeCanon)) { 3515 ICS.setBad(BadConversionSequence::bad_qualifiers, 3516 OrigFromType, ImplicitParamType); 3517 return ICS; 3518 } 3519 3520 // Check that we have either the same type or a derived type. It 3521 // affects the conversion rank. 3522 QualType ClassTypeCanon = S.Context.getCanonicalType(ClassType); 3523 ImplicitConversionKind SecondKind; 3524 if (ClassTypeCanon == FromTypeCanon.getLocalUnqualifiedType()) { 3525 SecondKind = ICK_Identity; 3526 } else if (S.IsDerivedFrom(FromType, ClassType)) 3527 SecondKind = ICK_Derived_To_Base; 3528 else { 3529 ICS.setBad(BadConversionSequence::unrelated_class, 3530 FromType, ImplicitParamType); 3531 return ICS; 3532 } 3533 3534 // Check the ref-qualifier. 3535 switch (Method->getRefQualifier()) { 3536 case RQ_None: 3537 // Do nothing; we don't care about lvalueness or rvalueness. 3538 break; 3539 3540 case RQ_LValue: 3541 if (!FromClassification.isLValue() && Quals != Qualifiers::Const) { 3542 // non-const lvalue reference cannot bind to an rvalue 3543 ICS.setBad(BadConversionSequence::lvalue_ref_to_rvalue, FromType, 3544 ImplicitParamType); 3545 return ICS; 3546 } 3547 break; 3548 3549 case RQ_RValue: 3550 if (!FromClassification.isRValue()) { 3551 // rvalue reference cannot bind to an lvalue 3552 ICS.setBad(BadConversionSequence::rvalue_ref_to_lvalue, FromType, 3553 ImplicitParamType); 3554 return ICS; 3555 } 3556 break; 3557 } 3558 3559 // Success. Mark this as a reference binding. 3560 ICS.setStandard(); 3561 ICS.Standard.setAsIdentityConversion(); 3562 ICS.Standard.Second = SecondKind; 3563 ICS.Standard.setFromType(FromType); 3564 ICS.Standard.setAllToTypes(ImplicitParamType); 3565 ICS.Standard.ReferenceBinding = true; 3566 ICS.Standard.DirectBinding = true; 3567 ICS.Standard.IsLvalueReference = Method->getRefQualifier() != RQ_RValue; 3568 ICS.Standard.BindsToFunctionLvalue = false; 3569 ICS.Standard.BindsToRvalue = FromClassification.isRValue(); 3570 ICS.Standard.BindsImplicitObjectArgumentWithoutRefQualifier 3571 = (Method->getRefQualifier() == RQ_None); 3572 return ICS; 3573} 3574 3575/// PerformObjectArgumentInitialization - Perform initialization of 3576/// the implicit object parameter for the given Method with the given 3577/// expression. 3578ExprResult 3579Sema::PerformObjectArgumentInitialization(Expr *From, 3580 NestedNameSpecifier *Qualifier, 3581 NamedDecl *FoundDecl, 3582 CXXMethodDecl *Method) { 3583 QualType FromRecordType, DestType; 3584 QualType ImplicitParamRecordType = 3585 Method->getThisType(Context)->getAs<PointerType>()->getPointeeType(); 3586 3587 Expr::Classification FromClassification; 3588 if (const PointerType *PT = From->getType()->getAs<PointerType>()) { 3589 FromRecordType = PT->getPointeeType(); 3590 DestType = Method->getThisType(Context); 3591 FromClassification = Expr::Classification::makeSimpleLValue(); 3592 } else { 3593 FromRecordType = From->getType(); 3594 DestType = ImplicitParamRecordType; 3595 FromClassification = From->Classify(Context); 3596 } 3597 3598 // Note that we always use the true parent context when performing 3599 // the actual argument initialization. 3600 ImplicitConversionSequence ICS 3601 = TryObjectArgumentInitialization(*this, From->getType(), FromClassification, 3602 Method, Method->getParent()); 3603 if (ICS.isBad()) { 3604 if (ICS.Bad.Kind == BadConversionSequence::bad_qualifiers) { 3605 Qualifiers FromQs = FromRecordType.getQualifiers(); 3606 Qualifiers ToQs = DestType.getQualifiers(); 3607 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 3608 if (CVR) { 3609 Diag(From->getSourceRange().getBegin(), 3610 diag::err_member_function_call_bad_cvr) 3611 << Method->getDeclName() << FromRecordType << (CVR - 1) 3612 << From->getSourceRange(); 3613 Diag(Method->getLocation(), diag::note_previous_decl) 3614 << Method->getDeclName(); 3615 return ExprError(); 3616 } 3617 } 3618 3619 return Diag(From->getSourceRange().getBegin(), 3620 diag::err_implicit_object_parameter_init) 3621 << ImplicitParamRecordType << FromRecordType << From->getSourceRange(); 3622 } 3623 3624 if (ICS.Standard.Second == ICK_Derived_To_Base) { 3625 ExprResult FromRes = 3626 PerformObjectMemberConversion(From, Qualifier, FoundDecl, Method); 3627 if (FromRes.isInvalid()) 3628 return ExprError(); 3629 From = FromRes.take(); 3630 } 3631 3632 if (!Context.hasSameType(From->getType(), DestType)) 3633 From = ImpCastExprToType(From, DestType, CK_NoOp, 3634 From->getType()->isPointerType() ? VK_RValue : VK_LValue).take(); 3635 return Owned(From); 3636} 3637 3638/// TryContextuallyConvertToBool - Attempt to contextually convert the 3639/// expression From to bool (C++0x [conv]p3). 3640static ImplicitConversionSequence 3641TryContextuallyConvertToBool(Sema &S, Expr *From) { 3642 // FIXME: This is pretty broken. 3643 return TryImplicitConversion(S, From, S.Context.BoolTy, 3644 // FIXME: Are these flags correct? 3645 /*SuppressUserConversions=*/false, 3646 /*AllowExplicit=*/true, 3647 /*InOverloadResolution=*/false, 3648 /*CStyle=*/false); 3649} 3650 3651/// PerformContextuallyConvertToBool - Perform a contextual conversion 3652/// of the expression From to bool (C++0x [conv]p3). 3653ExprResult Sema::PerformContextuallyConvertToBool(Expr *From) { 3654 ImplicitConversionSequence ICS = TryContextuallyConvertToBool(*this, From); 3655 if (!ICS.isBad()) 3656 return PerformImplicitConversion(From, Context.BoolTy, ICS, AA_Converting); 3657 3658 if (!DiagnoseMultipleUserDefinedConversion(From, Context.BoolTy)) 3659 return Diag(From->getSourceRange().getBegin(), 3660 diag::err_typecheck_bool_condition) 3661 << From->getType() << From->getSourceRange(); 3662 return ExprError(); 3663} 3664 3665/// TryContextuallyConvertToObjCId - Attempt to contextually convert the 3666/// expression From to 'id'. 3667static ImplicitConversionSequence 3668TryContextuallyConvertToObjCId(Sema &S, Expr *From) { 3669 QualType Ty = S.Context.getObjCIdType(); 3670 return TryImplicitConversion(S, From, Ty, 3671 // FIXME: Are these flags correct? 3672 /*SuppressUserConversions=*/false, 3673 /*AllowExplicit=*/true, 3674 /*InOverloadResolution=*/false, 3675 /*CStyle=*/false); 3676} 3677 3678/// PerformContextuallyConvertToObjCId - Perform a contextual conversion 3679/// of the expression From to 'id'. 3680ExprResult Sema::PerformContextuallyConvertToObjCId(Expr *From) { 3681 QualType Ty = Context.getObjCIdType(); 3682 ImplicitConversionSequence ICS = TryContextuallyConvertToObjCId(*this, From); 3683 if (!ICS.isBad()) 3684 return PerformImplicitConversion(From, Ty, ICS, AA_Converting); 3685 return ExprError(); 3686} 3687 3688/// \brief Attempt to convert the given expression to an integral or 3689/// enumeration type. 3690/// 3691/// This routine will attempt to convert an expression of class type to an 3692/// integral or enumeration type, if that class type only has a single 3693/// conversion to an integral or enumeration type. 3694/// 3695/// \param Loc The source location of the construct that requires the 3696/// conversion. 3697/// 3698/// \param FromE The expression we're converting from. 3699/// 3700/// \param NotIntDiag The diagnostic to be emitted if the expression does not 3701/// have integral or enumeration type. 3702/// 3703/// \param IncompleteDiag The diagnostic to be emitted if the expression has 3704/// incomplete class type. 3705/// 3706/// \param ExplicitConvDiag The diagnostic to be emitted if we're calling an 3707/// explicit conversion function (because no implicit conversion functions 3708/// were available). This is a recovery mode. 3709/// 3710/// \param ExplicitConvNote The note to be emitted with \p ExplicitConvDiag, 3711/// showing which conversion was picked. 3712/// 3713/// \param AmbigDiag The diagnostic to be emitted if there is more than one 3714/// conversion function that could convert to integral or enumeration type. 3715/// 3716/// \param AmbigNote The note to be emitted with \p AmbigDiag for each 3717/// usable conversion function. 3718/// 3719/// \param ConvDiag The diagnostic to be emitted if we are calling a conversion 3720/// function, which may be an extension in this case. 3721/// 3722/// \returns The expression, converted to an integral or enumeration type if 3723/// successful. 3724ExprResult 3725Sema::ConvertToIntegralOrEnumerationType(SourceLocation Loc, Expr *From, 3726 const PartialDiagnostic &NotIntDiag, 3727 const PartialDiagnostic &IncompleteDiag, 3728 const PartialDiagnostic &ExplicitConvDiag, 3729 const PartialDiagnostic &ExplicitConvNote, 3730 const PartialDiagnostic &AmbigDiag, 3731 const PartialDiagnostic &AmbigNote, 3732 const PartialDiagnostic &ConvDiag) { 3733 // We can't perform any more checking for type-dependent expressions. 3734 if (From->isTypeDependent()) 3735 return Owned(From); 3736 3737 // If the expression already has integral or enumeration type, we're golden. 3738 QualType T = From->getType(); 3739 if (T->isIntegralOrEnumerationType()) 3740 return Owned(From); 3741 3742 // FIXME: Check for missing '()' if T is a function type? 3743 3744 // If we don't have a class type in C++, there's no way we can get an 3745 // expression of integral or enumeration type. 3746 const RecordType *RecordTy = T->getAs<RecordType>(); 3747 if (!RecordTy || !getLangOptions().CPlusPlus) { 3748 Diag(Loc, NotIntDiag) 3749 << T << From->getSourceRange(); 3750 return Owned(From); 3751 } 3752 3753 // We must have a complete class type. 3754 if (RequireCompleteType(Loc, T, IncompleteDiag)) 3755 return Owned(From); 3756 3757 // Look for a conversion to an integral or enumeration type. 3758 UnresolvedSet<4> ViableConversions; 3759 UnresolvedSet<4> ExplicitConversions; 3760 const UnresolvedSetImpl *Conversions 3761 = cast<CXXRecordDecl>(RecordTy->getDecl())->getVisibleConversionFunctions(); 3762 3763 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 3764 E = Conversions->end(); 3765 I != E; 3766 ++I) { 3767 if (CXXConversionDecl *Conversion 3768 = dyn_cast<CXXConversionDecl>((*I)->getUnderlyingDecl())) 3769 if (Conversion->getConversionType().getNonReferenceType() 3770 ->isIntegralOrEnumerationType()) { 3771 if (Conversion->isExplicit()) 3772 ExplicitConversions.addDecl(I.getDecl(), I.getAccess()); 3773 else 3774 ViableConversions.addDecl(I.getDecl(), I.getAccess()); 3775 } 3776 } 3777 3778 switch (ViableConversions.size()) { 3779 case 0: 3780 if (ExplicitConversions.size() == 1) { 3781 DeclAccessPair Found = ExplicitConversions[0]; 3782 CXXConversionDecl *Conversion 3783 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 3784 3785 // The user probably meant to invoke the given explicit 3786 // conversion; use it. 3787 QualType ConvTy 3788 = Conversion->getConversionType().getNonReferenceType(); 3789 std::string TypeStr; 3790 ConvTy.getAsStringInternal(TypeStr, Context.PrintingPolicy); 3791 3792 Diag(Loc, ExplicitConvDiag) 3793 << T << ConvTy 3794 << FixItHint::CreateInsertion(From->getLocStart(), 3795 "static_cast<" + TypeStr + ">(") 3796 << FixItHint::CreateInsertion(PP.getLocForEndOfToken(From->getLocEnd()), 3797 ")"); 3798 Diag(Conversion->getLocation(), ExplicitConvNote) 3799 << ConvTy->isEnumeralType() << ConvTy; 3800 3801 // If we aren't in a SFINAE context, build a call to the 3802 // explicit conversion function. 3803 if (isSFINAEContext()) 3804 return ExprError(); 3805 3806 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 3807 ExprResult Result = BuildCXXMemberCallExpr(From, Found, Conversion); 3808 if (Result.isInvalid()) 3809 return ExprError(); 3810 3811 From = Result.get(); 3812 } 3813 3814 // We'll complain below about a non-integral condition type. 3815 break; 3816 3817 case 1: { 3818 // Apply this conversion. 3819 DeclAccessPair Found = ViableConversions[0]; 3820 CheckMemberOperatorAccess(From->getExprLoc(), From, 0, Found); 3821 3822 CXXConversionDecl *Conversion 3823 = cast<CXXConversionDecl>(Found->getUnderlyingDecl()); 3824 QualType ConvTy 3825 = Conversion->getConversionType().getNonReferenceType(); 3826 if (ConvDiag.getDiagID()) { 3827 if (isSFINAEContext()) 3828 return ExprError(); 3829 3830 Diag(Loc, ConvDiag) 3831 << T << ConvTy->isEnumeralType() << ConvTy << From->getSourceRange(); 3832 } 3833 3834 ExprResult Result = BuildCXXMemberCallExpr(From, Found, 3835 cast<CXXConversionDecl>(Found->getUnderlyingDecl())); 3836 if (Result.isInvalid()) 3837 return ExprError(); 3838 3839 From = Result.get(); 3840 break; 3841 } 3842 3843 default: 3844 Diag(Loc, AmbigDiag) 3845 << T << From->getSourceRange(); 3846 for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) { 3847 CXXConversionDecl *Conv 3848 = cast<CXXConversionDecl>(ViableConversions[I]->getUnderlyingDecl()); 3849 QualType ConvTy = Conv->getConversionType().getNonReferenceType(); 3850 Diag(Conv->getLocation(), AmbigNote) 3851 << ConvTy->isEnumeralType() << ConvTy; 3852 } 3853 return Owned(From); 3854 } 3855 3856 if (!From->getType()->isIntegralOrEnumerationType()) 3857 Diag(Loc, NotIntDiag) 3858 << From->getType() << From->getSourceRange(); 3859 3860 return Owned(From); 3861} 3862 3863/// AddOverloadCandidate - Adds the given function to the set of 3864/// candidate functions, using the given function call arguments. If 3865/// @p SuppressUserConversions, then don't allow user-defined 3866/// conversions via constructors or conversion operators. 3867/// 3868/// \para PartialOverloading true if we are performing "partial" overloading 3869/// based on an incomplete set of function arguments. This feature is used by 3870/// code completion. 3871void 3872Sema::AddOverloadCandidate(FunctionDecl *Function, 3873 DeclAccessPair FoundDecl, 3874 Expr **Args, unsigned NumArgs, 3875 OverloadCandidateSet& CandidateSet, 3876 bool SuppressUserConversions, 3877 bool PartialOverloading) { 3878 const FunctionProtoType* Proto 3879 = dyn_cast<FunctionProtoType>(Function->getType()->getAs<FunctionType>()); 3880 assert(Proto && "Functions without a prototype cannot be overloaded"); 3881 assert(!Function->getDescribedFunctionTemplate() && 3882 "Use AddTemplateOverloadCandidate for function templates"); 3883 3884 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { 3885 if (!isa<CXXConstructorDecl>(Method)) { 3886 // If we get here, it's because we're calling a member function 3887 // that is named without a member access expression (e.g., 3888 // "this->f") that was either written explicitly or created 3889 // implicitly. This can happen with a qualified call to a member 3890 // function, e.g., X::f(). We use an empty type for the implied 3891 // object argument (C++ [over.call.func]p3), and the acting context 3892 // is irrelevant. 3893 AddMethodCandidate(Method, FoundDecl, Method->getParent(), 3894 QualType(), Expr::Classification::makeSimpleLValue(), 3895 Args, NumArgs, CandidateSet, 3896 SuppressUserConversions); 3897 return; 3898 } 3899 // We treat a constructor like a non-member function, since its object 3900 // argument doesn't participate in overload resolution. 3901 } 3902 3903 if (!CandidateSet.isNewCandidate(Function)) 3904 return; 3905 3906 // Overload resolution is always an unevaluated context. 3907 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 3908 3909 if (CXXConstructorDecl *Constructor = dyn_cast<CXXConstructorDecl>(Function)){ 3910 // C++ [class.copy]p3: 3911 // A member function template is never instantiated to perform the copy 3912 // of a class object to an object of its class type. 3913 QualType ClassType = Context.getTypeDeclType(Constructor->getParent()); 3914 if (NumArgs == 1 && 3915 Constructor->isSpecializationCopyingObject() && 3916 (Context.hasSameUnqualifiedType(ClassType, Args[0]->getType()) || 3917 IsDerivedFrom(Args[0]->getType(), ClassType))) 3918 return; 3919 } 3920 3921 // Add this candidate 3922 CandidateSet.push_back(OverloadCandidate()); 3923 OverloadCandidate& Candidate = CandidateSet.back(); 3924 Candidate.FoundDecl = FoundDecl; 3925 Candidate.Function = Function; 3926 Candidate.Viable = true; 3927 Candidate.IsSurrogate = false; 3928 Candidate.IgnoreObjectArgument = false; 3929 Candidate.ExplicitCallArguments = NumArgs; 3930 3931 unsigned NumArgsInProto = Proto->getNumArgs(); 3932 3933 // (C++ 13.3.2p2): A candidate function having fewer than m 3934 // parameters is viable only if it has an ellipsis in its parameter 3935 // list (8.3.5). 3936 if ((NumArgs + (PartialOverloading && NumArgs)) > NumArgsInProto && 3937 !Proto->isVariadic()) { 3938 Candidate.Viable = false; 3939 Candidate.FailureKind = ovl_fail_too_many_arguments; 3940 return; 3941 } 3942 3943 // (C++ 13.3.2p2): A candidate function having more than m parameters 3944 // is viable only if the (m+1)st parameter has a default argument 3945 // (8.3.6). For the purposes of overload resolution, the 3946 // parameter list is truncated on the right, so that there are 3947 // exactly m parameters. 3948 unsigned MinRequiredArgs = Function->getMinRequiredArguments(); 3949 if (NumArgs < MinRequiredArgs && !PartialOverloading) { 3950 // Not enough arguments. 3951 Candidate.Viable = false; 3952 Candidate.FailureKind = ovl_fail_too_few_arguments; 3953 return; 3954 } 3955 3956 // Determine the implicit conversion sequences for each of the 3957 // arguments. 3958 Candidate.Conversions.resize(NumArgs); 3959 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 3960 if (ArgIdx < NumArgsInProto) { 3961 // (C++ 13.3.2p3): for F to be a viable function, there shall 3962 // exist for each argument an implicit conversion sequence 3963 // (13.3.3.1) that converts that argument to the corresponding 3964 // parameter of F. 3965 QualType ParamType = Proto->getArgType(ArgIdx); 3966 Candidate.Conversions[ArgIdx] 3967 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 3968 SuppressUserConversions, 3969 /*InOverloadResolution=*/true); 3970 if (Candidate.Conversions[ArgIdx].isBad()) { 3971 Candidate.Viable = false; 3972 Candidate.FailureKind = ovl_fail_bad_conversion; 3973 break; 3974 } 3975 } else { 3976 // (C++ 13.3.2p2): For the purposes of overload resolution, any 3977 // argument for which there is no corresponding parameter is 3978 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 3979 Candidate.Conversions[ArgIdx].setEllipsis(); 3980 } 3981 } 3982} 3983 3984/// \brief Add all of the function declarations in the given function set to 3985/// the overload canddiate set. 3986void Sema::AddFunctionCandidates(const UnresolvedSetImpl &Fns, 3987 Expr **Args, unsigned NumArgs, 3988 OverloadCandidateSet& CandidateSet, 3989 bool SuppressUserConversions) { 3990 for (UnresolvedSetIterator F = Fns.begin(), E = Fns.end(); F != E; ++F) { 3991 NamedDecl *D = F.getDecl()->getUnderlyingDecl(); 3992 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) { 3993 if (isa<CXXMethodDecl>(FD) && !cast<CXXMethodDecl>(FD)->isStatic()) 3994 AddMethodCandidate(cast<CXXMethodDecl>(FD), F.getPair(), 3995 cast<CXXMethodDecl>(FD)->getParent(), 3996 Args[0]->getType(), Args[0]->Classify(Context), 3997 Args + 1, NumArgs - 1, 3998 CandidateSet, SuppressUserConversions); 3999 else 4000 AddOverloadCandidate(FD, F.getPair(), Args, NumArgs, CandidateSet, 4001 SuppressUserConversions); 4002 } else { 4003 FunctionTemplateDecl *FunTmpl = cast<FunctionTemplateDecl>(D); 4004 if (isa<CXXMethodDecl>(FunTmpl->getTemplatedDecl()) && 4005 !cast<CXXMethodDecl>(FunTmpl->getTemplatedDecl())->isStatic()) 4006 AddMethodTemplateCandidate(FunTmpl, F.getPair(), 4007 cast<CXXRecordDecl>(FunTmpl->getDeclContext()), 4008 /*FIXME: explicit args */ 0, 4009 Args[0]->getType(), 4010 Args[0]->Classify(Context), 4011 Args + 1, NumArgs - 1, 4012 CandidateSet, 4013 SuppressUserConversions); 4014 else 4015 AddTemplateOverloadCandidate(FunTmpl, F.getPair(), 4016 /*FIXME: explicit args */ 0, 4017 Args, NumArgs, CandidateSet, 4018 SuppressUserConversions); 4019 } 4020 } 4021} 4022 4023/// AddMethodCandidate - Adds a named decl (which is some kind of 4024/// method) as a method candidate to the given overload set. 4025void Sema::AddMethodCandidate(DeclAccessPair FoundDecl, 4026 QualType ObjectType, 4027 Expr::Classification ObjectClassification, 4028 Expr **Args, unsigned NumArgs, 4029 OverloadCandidateSet& CandidateSet, 4030 bool SuppressUserConversions) { 4031 NamedDecl *Decl = FoundDecl.getDecl(); 4032 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(Decl->getDeclContext()); 4033 4034 if (isa<UsingShadowDecl>(Decl)) 4035 Decl = cast<UsingShadowDecl>(Decl)->getTargetDecl(); 4036 4037 if (FunctionTemplateDecl *TD = dyn_cast<FunctionTemplateDecl>(Decl)) { 4038 assert(isa<CXXMethodDecl>(TD->getTemplatedDecl()) && 4039 "Expected a member function template"); 4040 AddMethodTemplateCandidate(TD, FoundDecl, ActingContext, 4041 /*ExplicitArgs*/ 0, 4042 ObjectType, ObjectClassification, Args, NumArgs, 4043 CandidateSet, 4044 SuppressUserConversions); 4045 } else { 4046 AddMethodCandidate(cast<CXXMethodDecl>(Decl), FoundDecl, ActingContext, 4047 ObjectType, ObjectClassification, Args, NumArgs, 4048 CandidateSet, SuppressUserConversions); 4049 } 4050} 4051 4052/// AddMethodCandidate - Adds the given C++ member function to the set 4053/// of candidate functions, using the given function call arguments 4054/// and the object argument (@c Object). For example, in a call 4055/// @c o.f(a1,a2), @c Object will contain @c o and @c Args will contain 4056/// both @c a1 and @c a2. If @p SuppressUserConversions, then don't 4057/// allow user-defined conversions via constructors or conversion 4058/// operators. 4059void 4060Sema::AddMethodCandidate(CXXMethodDecl *Method, DeclAccessPair FoundDecl, 4061 CXXRecordDecl *ActingContext, QualType ObjectType, 4062 Expr::Classification ObjectClassification, 4063 Expr **Args, unsigned NumArgs, 4064 OverloadCandidateSet& CandidateSet, 4065 bool SuppressUserConversions) { 4066 const FunctionProtoType* Proto 4067 = dyn_cast<FunctionProtoType>(Method->getType()->getAs<FunctionType>()); 4068 assert(Proto && "Methods without a prototype cannot be overloaded"); 4069 assert(!isa<CXXConstructorDecl>(Method) && 4070 "Use AddOverloadCandidate for constructors"); 4071 4072 if (!CandidateSet.isNewCandidate(Method)) 4073 return; 4074 4075 // Overload resolution is always an unevaluated context. 4076 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4077 4078 // Add this candidate 4079 CandidateSet.push_back(OverloadCandidate()); 4080 OverloadCandidate& Candidate = CandidateSet.back(); 4081 Candidate.FoundDecl = FoundDecl; 4082 Candidate.Function = Method; 4083 Candidate.IsSurrogate = false; 4084 Candidate.IgnoreObjectArgument = false; 4085 Candidate.ExplicitCallArguments = NumArgs; 4086 4087 unsigned NumArgsInProto = Proto->getNumArgs(); 4088 4089 // (C++ 13.3.2p2): A candidate function having fewer than m 4090 // parameters is viable only if it has an ellipsis in its parameter 4091 // list (8.3.5). 4092 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4093 Candidate.Viable = false; 4094 Candidate.FailureKind = ovl_fail_too_many_arguments; 4095 return; 4096 } 4097 4098 // (C++ 13.3.2p2): A candidate function having more than m parameters 4099 // is viable only if the (m+1)st parameter has a default argument 4100 // (8.3.6). For the purposes of overload resolution, the 4101 // parameter list is truncated on the right, so that there are 4102 // exactly m parameters. 4103 unsigned MinRequiredArgs = Method->getMinRequiredArguments(); 4104 if (NumArgs < MinRequiredArgs) { 4105 // Not enough arguments. 4106 Candidate.Viable = false; 4107 Candidate.FailureKind = ovl_fail_too_few_arguments; 4108 return; 4109 } 4110 4111 Candidate.Viable = true; 4112 Candidate.Conversions.resize(NumArgs + 1); 4113 4114 if (Method->isStatic() || ObjectType.isNull()) 4115 // The implicit object argument is ignored. 4116 Candidate.IgnoreObjectArgument = true; 4117 else { 4118 // Determine the implicit conversion sequence for the object 4119 // parameter. 4120 Candidate.Conversions[0] 4121 = TryObjectArgumentInitialization(*this, ObjectType, ObjectClassification, 4122 Method, ActingContext); 4123 if (Candidate.Conversions[0].isBad()) { 4124 Candidate.Viable = false; 4125 Candidate.FailureKind = ovl_fail_bad_conversion; 4126 return; 4127 } 4128 } 4129 4130 // Determine the implicit conversion sequences for each of the 4131 // arguments. 4132 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4133 if (ArgIdx < NumArgsInProto) { 4134 // (C++ 13.3.2p3): for F to be a viable function, there shall 4135 // exist for each argument an implicit conversion sequence 4136 // (13.3.3.1) that converts that argument to the corresponding 4137 // parameter of F. 4138 QualType ParamType = Proto->getArgType(ArgIdx); 4139 Candidate.Conversions[ArgIdx + 1] 4140 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4141 SuppressUserConversions, 4142 /*InOverloadResolution=*/true); 4143 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4144 Candidate.Viable = false; 4145 Candidate.FailureKind = ovl_fail_bad_conversion; 4146 break; 4147 } 4148 } else { 4149 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4150 // argument for which there is no corresponding parameter is 4151 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4152 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4153 } 4154 } 4155} 4156 4157/// \brief Add a C++ member function template as a candidate to the candidate 4158/// set, using template argument deduction to produce an appropriate member 4159/// function template specialization. 4160void 4161Sema::AddMethodTemplateCandidate(FunctionTemplateDecl *MethodTmpl, 4162 DeclAccessPair FoundDecl, 4163 CXXRecordDecl *ActingContext, 4164 TemplateArgumentListInfo *ExplicitTemplateArgs, 4165 QualType ObjectType, 4166 Expr::Classification ObjectClassification, 4167 Expr **Args, unsigned NumArgs, 4168 OverloadCandidateSet& CandidateSet, 4169 bool SuppressUserConversions) { 4170 if (!CandidateSet.isNewCandidate(MethodTmpl)) 4171 return; 4172 4173 // C++ [over.match.funcs]p7: 4174 // In each case where a candidate is a function template, candidate 4175 // function template specializations are generated using template argument 4176 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4177 // candidate functions in the usual way.113) A given name can refer to one 4178 // or more function templates and also to a set of overloaded non-template 4179 // functions. In such a case, the candidate functions generated from each 4180 // function template are combined with the set of non-template candidate 4181 // functions. 4182 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4183 FunctionDecl *Specialization = 0; 4184 if (TemplateDeductionResult Result 4185 = DeduceTemplateArguments(MethodTmpl, ExplicitTemplateArgs, 4186 Args, NumArgs, Specialization, Info)) { 4187 CandidateSet.push_back(OverloadCandidate()); 4188 OverloadCandidate &Candidate = CandidateSet.back(); 4189 Candidate.FoundDecl = FoundDecl; 4190 Candidate.Function = MethodTmpl->getTemplatedDecl(); 4191 Candidate.Viable = false; 4192 Candidate.FailureKind = ovl_fail_bad_deduction; 4193 Candidate.IsSurrogate = false; 4194 Candidate.IgnoreObjectArgument = false; 4195 Candidate.ExplicitCallArguments = NumArgs; 4196 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4197 Info); 4198 return; 4199 } 4200 4201 // Add the function template specialization produced by template argument 4202 // deduction as a candidate. 4203 assert(Specialization && "Missing member function template specialization?"); 4204 assert(isa<CXXMethodDecl>(Specialization) && 4205 "Specialization is not a member function?"); 4206 AddMethodCandidate(cast<CXXMethodDecl>(Specialization), FoundDecl, 4207 ActingContext, ObjectType, ObjectClassification, 4208 Args, NumArgs, CandidateSet, SuppressUserConversions); 4209} 4210 4211/// \brief Add a C++ function template specialization as a candidate 4212/// in the candidate set, using template argument deduction to produce 4213/// an appropriate function template specialization. 4214void 4215Sema::AddTemplateOverloadCandidate(FunctionTemplateDecl *FunctionTemplate, 4216 DeclAccessPair FoundDecl, 4217 TemplateArgumentListInfo *ExplicitTemplateArgs, 4218 Expr **Args, unsigned NumArgs, 4219 OverloadCandidateSet& CandidateSet, 4220 bool SuppressUserConversions) { 4221 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4222 return; 4223 4224 // C++ [over.match.funcs]p7: 4225 // In each case where a candidate is a function template, candidate 4226 // function template specializations are generated using template argument 4227 // deduction (14.8.3, 14.8.2). Those candidates are then handled as 4228 // candidate functions in the usual way.113) A given name can refer to one 4229 // or more function templates and also to a set of overloaded non-template 4230 // functions. In such a case, the candidate functions generated from each 4231 // function template are combined with the set of non-template candidate 4232 // functions. 4233 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4234 FunctionDecl *Specialization = 0; 4235 if (TemplateDeductionResult Result 4236 = DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs, 4237 Args, NumArgs, Specialization, Info)) { 4238 CandidateSet.push_back(OverloadCandidate()); 4239 OverloadCandidate &Candidate = CandidateSet.back(); 4240 Candidate.FoundDecl = FoundDecl; 4241 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4242 Candidate.Viable = false; 4243 Candidate.FailureKind = ovl_fail_bad_deduction; 4244 Candidate.IsSurrogate = false; 4245 Candidate.IgnoreObjectArgument = false; 4246 Candidate.ExplicitCallArguments = NumArgs; 4247 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4248 Info); 4249 return; 4250 } 4251 4252 // Add the function template specialization produced by template argument 4253 // deduction as a candidate. 4254 assert(Specialization && "Missing function template specialization?"); 4255 AddOverloadCandidate(Specialization, FoundDecl, Args, NumArgs, CandidateSet, 4256 SuppressUserConversions); 4257} 4258 4259/// AddConversionCandidate - Add a C++ conversion function as a 4260/// candidate in the candidate set (C++ [over.match.conv], 4261/// C++ [over.match.copy]). From is the expression we're converting from, 4262/// and ToType is the type that we're eventually trying to convert to 4263/// (which may or may not be the same type as the type that the 4264/// conversion function produces). 4265void 4266Sema::AddConversionCandidate(CXXConversionDecl *Conversion, 4267 DeclAccessPair FoundDecl, 4268 CXXRecordDecl *ActingContext, 4269 Expr *From, QualType ToType, 4270 OverloadCandidateSet& CandidateSet) { 4271 assert(!Conversion->getDescribedFunctionTemplate() && 4272 "Conversion function templates use AddTemplateConversionCandidate"); 4273 QualType ConvType = Conversion->getConversionType().getNonReferenceType(); 4274 if (!CandidateSet.isNewCandidate(Conversion)) 4275 return; 4276 4277 // Overload resolution is always an unevaluated context. 4278 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4279 4280 // Add this candidate 4281 CandidateSet.push_back(OverloadCandidate()); 4282 OverloadCandidate& Candidate = CandidateSet.back(); 4283 Candidate.FoundDecl = FoundDecl; 4284 Candidate.Function = Conversion; 4285 Candidate.IsSurrogate = false; 4286 Candidate.IgnoreObjectArgument = false; 4287 Candidate.FinalConversion.setAsIdentityConversion(); 4288 Candidate.FinalConversion.setFromType(ConvType); 4289 Candidate.FinalConversion.setAllToTypes(ToType); 4290 Candidate.Viable = true; 4291 Candidate.Conversions.resize(1); 4292 Candidate.ExplicitCallArguments = 1; 4293 4294 // C++ [over.match.funcs]p4: 4295 // For conversion functions, the function is considered to be a member of 4296 // the class of the implicit implied object argument for the purpose of 4297 // defining the type of the implicit object parameter. 4298 // 4299 // Determine the implicit conversion sequence for the implicit 4300 // object parameter. 4301 QualType ImplicitParamType = From->getType(); 4302 if (const PointerType *FromPtrType = ImplicitParamType->getAs<PointerType>()) 4303 ImplicitParamType = FromPtrType->getPointeeType(); 4304 CXXRecordDecl *ConversionContext 4305 = cast<CXXRecordDecl>(ImplicitParamType->getAs<RecordType>()->getDecl()); 4306 4307 Candidate.Conversions[0] 4308 = TryObjectArgumentInitialization(*this, From->getType(), 4309 From->Classify(Context), 4310 Conversion, ConversionContext); 4311 4312 if (Candidate.Conversions[0].isBad()) { 4313 Candidate.Viable = false; 4314 Candidate.FailureKind = ovl_fail_bad_conversion; 4315 return; 4316 } 4317 4318 // We won't go through a user-define type conversion function to convert a 4319 // derived to base as such conversions are given Conversion Rank. They only 4320 // go through a copy constructor. 13.3.3.1.2-p4 [over.ics.user] 4321 QualType FromCanon 4322 = Context.getCanonicalType(From->getType().getUnqualifiedType()); 4323 QualType ToCanon = Context.getCanonicalType(ToType).getUnqualifiedType(); 4324 if (FromCanon == ToCanon || IsDerivedFrom(FromCanon, ToCanon)) { 4325 Candidate.Viable = false; 4326 Candidate.FailureKind = ovl_fail_trivial_conversion; 4327 return; 4328 } 4329 4330 // To determine what the conversion from the result of calling the 4331 // conversion function to the type we're eventually trying to 4332 // convert to (ToType), we need to synthesize a call to the 4333 // conversion function and attempt copy initialization from it. This 4334 // makes sure that we get the right semantics with respect to 4335 // lvalues/rvalues and the type. Fortunately, we can allocate this 4336 // call on the stack and we don't need its arguments to be 4337 // well-formed. 4338 DeclRefExpr ConversionRef(Conversion, Conversion->getType(), 4339 VK_LValue, From->getLocStart()); 4340 ImplicitCastExpr ConversionFn(ImplicitCastExpr::OnStack, 4341 Context.getPointerType(Conversion->getType()), 4342 CK_FunctionToPointerDecay, 4343 &ConversionRef, VK_RValue); 4344 4345 QualType CallResultType 4346 = Conversion->getConversionType().getNonLValueExprType(Context); 4347 if (RequireCompleteType(From->getLocStart(), CallResultType, 0)) { 4348 Candidate.Viable = false; 4349 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4350 return; 4351 } 4352 4353 ExprValueKind VK = Expr::getValueKindForType(Conversion->getConversionType()); 4354 4355 // Note that it is safe to allocate CallExpr on the stack here because 4356 // there are 0 arguments (i.e., nothing is allocated using ASTContext's 4357 // allocator). 4358 CallExpr Call(Context, &ConversionFn, 0, 0, CallResultType, VK, 4359 From->getLocStart()); 4360 ImplicitConversionSequence ICS = 4361 TryCopyInitialization(*this, &Call, ToType, 4362 /*SuppressUserConversions=*/true, 4363 /*InOverloadResolution=*/false); 4364 4365 switch (ICS.getKind()) { 4366 case ImplicitConversionSequence::StandardConversion: 4367 Candidate.FinalConversion = ICS.Standard; 4368 4369 // C++ [over.ics.user]p3: 4370 // If the user-defined conversion is specified by a specialization of a 4371 // conversion function template, the second standard conversion sequence 4372 // shall have exact match rank. 4373 if (Conversion->getPrimaryTemplate() && 4374 GetConversionRank(ICS.Standard.Second) != ICR_Exact_Match) { 4375 Candidate.Viable = false; 4376 Candidate.FailureKind = ovl_fail_final_conversion_not_exact; 4377 } 4378 4379 // C++0x [dcl.init.ref]p5: 4380 // In the second case, if the reference is an rvalue reference and 4381 // the second standard conversion sequence of the user-defined 4382 // conversion sequence includes an lvalue-to-rvalue conversion, the 4383 // program is ill-formed. 4384 if (ToType->isRValueReferenceType() && 4385 ICS.Standard.First == ICK_Lvalue_To_Rvalue) { 4386 Candidate.Viable = false; 4387 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4388 } 4389 break; 4390 4391 case ImplicitConversionSequence::BadConversion: 4392 Candidate.Viable = false; 4393 Candidate.FailureKind = ovl_fail_bad_final_conversion; 4394 break; 4395 4396 default: 4397 assert(false && 4398 "Can only end up with a standard conversion sequence or failure"); 4399 } 4400} 4401 4402/// \brief Adds a conversion function template specialization 4403/// candidate to the overload set, using template argument deduction 4404/// to deduce the template arguments of the conversion function 4405/// template from the type that we are converting to (C++ 4406/// [temp.deduct.conv]). 4407void 4408Sema::AddTemplateConversionCandidate(FunctionTemplateDecl *FunctionTemplate, 4409 DeclAccessPair FoundDecl, 4410 CXXRecordDecl *ActingDC, 4411 Expr *From, QualType ToType, 4412 OverloadCandidateSet &CandidateSet) { 4413 assert(isa<CXXConversionDecl>(FunctionTemplate->getTemplatedDecl()) && 4414 "Only conversion function templates permitted here"); 4415 4416 if (!CandidateSet.isNewCandidate(FunctionTemplate)) 4417 return; 4418 4419 TemplateDeductionInfo Info(Context, CandidateSet.getLocation()); 4420 CXXConversionDecl *Specialization = 0; 4421 if (TemplateDeductionResult Result 4422 = DeduceTemplateArguments(FunctionTemplate, ToType, 4423 Specialization, Info)) { 4424 CandidateSet.push_back(OverloadCandidate()); 4425 OverloadCandidate &Candidate = CandidateSet.back(); 4426 Candidate.FoundDecl = FoundDecl; 4427 Candidate.Function = FunctionTemplate->getTemplatedDecl(); 4428 Candidate.Viable = false; 4429 Candidate.FailureKind = ovl_fail_bad_deduction; 4430 Candidate.IsSurrogate = false; 4431 Candidate.IgnoreObjectArgument = false; 4432 Candidate.ExplicitCallArguments = 1; 4433 Candidate.DeductionFailure = MakeDeductionFailureInfo(Context, Result, 4434 Info); 4435 return; 4436 } 4437 4438 // Add the conversion function template specialization produced by 4439 // template argument deduction as a candidate. 4440 assert(Specialization && "Missing function template specialization?"); 4441 AddConversionCandidate(Specialization, FoundDecl, ActingDC, From, ToType, 4442 CandidateSet); 4443} 4444 4445/// AddSurrogateCandidate - Adds a "surrogate" candidate function that 4446/// converts the given @c Object to a function pointer via the 4447/// conversion function @c Conversion, and then attempts to call it 4448/// with the given arguments (C++ [over.call.object]p2-4). Proto is 4449/// the type of function that we'll eventually be calling. 4450void Sema::AddSurrogateCandidate(CXXConversionDecl *Conversion, 4451 DeclAccessPair FoundDecl, 4452 CXXRecordDecl *ActingContext, 4453 const FunctionProtoType *Proto, 4454 Expr *Object, 4455 Expr **Args, unsigned NumArgs, 4456 OverloadCandidateSet& CandidateSet) { 4457 if (!CandidateSet.isNewCandidate(Conversion)) 4458 return; 4459 4460 // Overload resolution is always an unevaluated context. 4461 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4462 4463 CandidateSet.push_back(OverloadCandidate()); 4464 OverloadCandidate& Candidate = CandidateSet.back(); 4465 Candidate.FoundDecl = FoundDecl; 4466 Candidate.Function = 0; 4467 Candidate.Surrogate = Conversion; 4468 Candidate.Viable = true; 4469 Candidate.IsSurrogate = true; 4470 Candidate.IgnoreObjectArgument = false; 4471 Candidate.Conversions.resize(NumArgs + 1); 4472 Candidate.ExplicitCallArguments = NumArgs; 4473 4474 // Determine the implicit conversion sequence for the implicit 4475 // object parameter. 4476 ImplicitConversionSequence ObjectInit 4477 = TryObjectArgumentInitialization(*this, Object->getType(), 4478 Object->Classify(Context), 4479 Conversion, ActingContext); 4480 if (ObjectInit.isBad()) { 4481 Candidate.Viable = false; 4482 Candidate.FailureKind = ovl_fail_bad_conversion; 4483 Candidate.Conversions[0] = ObjectInit; 4484 return; 4485 } 4486 4487 // The first conversion is actually a user-defined conversion whose 4488 // first conversion is ObjectInit's standard conversion (which is 4489 // effectively a reference binding). Record it as such. 4490 Candidate.Conversions[0].setUserDefined(); 4491 Candidate.Conversions[0].UserDefined.Before = ObjectInit.Standard; 4492 Candidate.Conversions[0].UserDefined.EllipsisConversion = false; 4493 Candidate.Conversions[0].UserDefined.ConversionFunction = Conversion; 4494 Candidate.Conversions[0].UserDefined.FoundConversionFunction 4495 = FoundDecl.getDecl(); 4496 Candidate.Conversions[0].UserDefined.After 4497 = Candidate.Conversions[0].UserDefined.Before; 4498 Candidate.Conversions[0].UserDefined.After.setAsIdentityConversion(); 4499 4500 // Find the 4501 unsigned NumArgsInProto = Proto->getNumArgs(); 4502 4503 // (C++ 13.3.2p2): A candidate function having fewer than m 4504 // parameters is viable only if it has an ellipsis in its parameter 4505 // list (8.3.5). 4506 if (NumArgs > NumArgsInProto && !Proto->isVariadic()) { 4507 Candidate.Viable = false; 4508 Candidate.FailureKind = ovl_fail_too_many_arguments; 4509 return; 4510 } 4511 4512 // Function types don't have any default arguments, so just check if 4513 // we have enough arguments. 4514 if (NumArgs < NumArgsInProto) { 4515 // Not enough arguments. 4516 Candidate.Viable = false; 4517 Candidate.FailureKind = ovl_fail_too_few_arguments; 4518 return; 4519 } 4520 4521 // Determine the implicit conversion sequences for each of the 4522 // arguments. 4523 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4524 if (ArgIdx < NumArgsInProto) { 4525 // (C++ 13.3.2p3): for F to be a viable function, there shall 4526 // exist for each argument an implicit conversion sequence 4527 // (13.3.3.1) that converts that argument to the corresponding 4528 // parameter of F. 4529 QualType ParamType = Proto->getArgType(ArgIdx); 4530 Candidate.Conversions[ArgIdx + 1] 4531 = TryCopyInitialization(*this, Args[ArgIdx], ParamType, 4532 /*SuppressUserConversions=*/false, 4533 /*InOverloadResolution=*/false); 4534 if (Candidate.Conversions[ArgIdx + 1].isBad()) { 4535 Candidate.Viable = false; 4536 Candidate.FailureKind = ovl_fail_bad_conversion; 4537 break; 4538 } 4539 } else { 4540 // (C++ 13.3.2p2): For the purposes of overload resolution, any 4541 // argument for which there is no corresponding parameter is 4542 // considered to ""match the ellipsis" (C+ 13.3.3.1.3). 4543 Candidate.Conversions[ArgIdx + 1].setEllipsis(); 4544 } 4545 } 4546} 4547 4548/// \brief Add overload candidates for overloaded operators that are 4549/// member functions. 4550/// 4551/// Add the overloaded operator candidates that are member functions 4552/// for the operator Op that was used in an operator expression such 4553/// as "x Op y". , Args/NumArgs provides the operator arguments, and 4554/// CandidateSet will store the added overload candidates. (C++ 4555/// [over.match.oper]). 4556void Sema::AddMemberOperatorCandidates(OverloadedOperatorKind Op, 4557 SourceLocation OpLoc, 4558 Expr **Args, unsigned NumArgs, 4559 OverloadCandidateSet& CandidateSet, 4560 SourceRange OpRange) { 4561 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 4562 4563 // C++ [over.match.oper]p3: 4564 // For a unary operator @ with an operand of a type whose 4565 // cv-unqualified version is T1, and for a binary operator @ with 4566 // a left operand of a type whose cv-unqualified version is T1 and 4567 // a right operand of a type whose cv-unqualified version is T2, 4568 // three sets of candidate functions, designated member 4569 // candidates, non-member candidates and built-in candidates, are 4570 // constructed as follows: 4571 QualType T1 = Args[0]->getType(); 4572 4573 // -- If T1 is a class type, the set of member candidates is the 4574 // result of the qualified lookup of T1::operator@ 4575 // (13.3.1.1.1); otherwise, the set of member candidates is 4576 // empty. 4577 if (const RecordType *T1Rec = T1->getAs<RecordType>()) { 4578 // Complete the type if it can be completed. Otherwise, we're done. 4579 if (RequireCompleteType(OpLoc, T1, PDiag())) 4580 return; 4581 4582 LookupResult Operators(*this, OpName, OpLoc, LookupOrdinaryName); 4583 LookupQualifiedName(Operators, T1Rec->getDecl()); 4584 Operators.suppressDiagnostics(); 4585 4586 for (LookupResult::iterator Oper = Operators.begin(), 4587 OperEnd = Operators.end(); 4588 Oper != OperEnd; 4589 ++Oper) 4590 AddMethodCandidate(Oper.getPair(), Args[0]->getType(), 4591 Args[0]->Classify(Context), Args + 1, NumArgs - 1, 4592 CandidateSet, 4593 /* SuppressUserConversions = */ false); 4594 } 4595} 4596 4597/// AddBuiltinCandidate - Add a candidate for a built-in 4598/// operator. ResultTy and ParamTys are the result and parameter types 4599/// of the built-in candidate, respectively. Args and NumArgs are the 4600/// arguments being passed to the candidate. IsAssignmentOperator 4601/// should be true when this built-in candidate is an assignment 4602/// operator. NumContextualBoolArguments is the number of arguments 4603/// (at the beginning of the argument list) that will be contextually 4604/// converted to bool. 4605void Sema::AddBuiltinCandidate(QualType ResultTy, QualType *ParamTys, 4606 Expr **Args, unsigned NumArgs, 4607 OverloadCandidateSet& CandidateSet, 4608 bool IsAssignmentOperator, 4609 unsigned NumContextualBoolArguments) { 4610 // Overload resolution is always an unevaluated context. 4611 EnterExpressionEvaluationContext Unevaluated(*this, Sema::Unevaluated); 4612 4613 // Add this candidate 4614 CandidateSet.push_back(OverloadCandidate()); 4615 OverloadCandidate& Candidate = CandidateSet.back(); 4616 Candidate.FoundDecl = DeclAccessPair::make(0, AS_none); 4617 Candidate.Function = 0; 4618 Candidate.IsSurrogate = false; 4619 Candidate.IgnoreObjectArgument = false; 4620 Candidate.BuiltinTypes.ResultTy = ResultTy; 4621 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 4622 Candidate.BuiltinTypes.ParamTypes[ArgIdx] = ParamTys[ArgIdx]; 4623 4624 // Determine the implicit conversion sequences for each of the 4625 // arguments. 4626 Candidate.Viable = true; 4627 Candidate.Conversions.resize(NumArgs); 4628 Candidate.ExplicitCallArguments = NumArgs; 4629 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 4630 // C++ [over.match.oper]p4: 4631 // For the built-in assignment operators, conversions of the 4632 // left operand are restricted as follows: 4633 // -- no temporaries are introduced to hold the left operand, and 4634 // -- no user-defined conversions are applied to the left 4635 // operand to achieve a type match with the left-most 4636 // parameter of a built-in candidate. 4637 // 4638 // We block these conversions by turning off user-defined 4639 // conversions, since that is the only way that initialization of 4640 // a reference to a non-class type can occur from something that 4641 // is not of the same type. 4642 if (ArgIdx < NumContextualBoolArguments) { 4643 assert(ParamTys[ArgIdx] == Context.BoolTy && 4644 "Contextual conversion to bool requires bool type"); 4645 Candidate.Conversions[ArgIdx] 4646 = TryContextuallyConvertToBool(*this, Args[ArgIdx]); 4647 } else { 4648 Candidate.Conversions[ArgIdx] 4649 = TryCopyInitialization(*this, Args[ArgIdx], ParamTys[ArgIdx], 4650 ArgIdx == 0 && IsAssignmentOperator, 4651 /*InOverloadResolution=*/false); 4652 } 4653 if (Candidate.Conversions[ArgIdx].isBad()) { 4654 Candidate.Viable = false; 4655 Candidate.FailureKind = ovl_fail_bad_conversion; 4656 break; 4657 } 4658 } 4659} 4660 4661/// BuiltinCandidateTypeSet - A set of types that will be used for the 4662/// candidate operator functions for built-in operators (C++ 4663/// [over.built]). The types are separated into pointer types and 4664/// enumeration types. 4665class BuiltinCandidateTypeSet { 4666 /// TypeSet - A set of types. 4667 typedef llvm::SmallPtrSet<QualType, 8> TypeSet; 4668 4669 /// PointerTypes - The set of pointer types that will be used in the 4670 /// built-in candidates. 4671 TypeSet PointerTypes; 4672 4673 /// MemberPointerTypes - The set of member pointer types that will be 4674 /// used in the built-in candidates. 4675 TypeSet MemberPointerTypes; 4676 4677 /// EnumerationTypes - The set of enumeration types that will be 4678 /// used in the built-in candidates. 4679 TypeSet EnumerationTypes; 4680 4681 /// \brief The set of vector types that will be used in the built-in 4682 /// candidates. 4683 TypeSet VectorTypes; 4684 4685 /// \brief A flag indicating non-record types are viable candidates 4686 bool HasNonRecordTypes; 4687 4688 /// \brief A flag indicating whether either arithmetic or enumeration types 4689 /// were present in the candidate set. 4690 bool HasArithmeticOrEnumeralTypes; 4691 4692 /// Sema - The semantic analysis instance where we are building the 4693 /// candidate type set. 4694 Sema &SemaRef; 4695 4696 /// Context - The AST context in which we will build the type sets. 4697 ASTContext &Context; 4698 4699 bool AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 4700 const Qualifiers &VisibleQuals); 4701 bool AddMemberPointerWithMoreQualifiedTypeVariants(QualType Ty); 4702 4703public: 4704 /// iterator - Iterates through the types that are part of the set. 4705 typedef TypeSet::iterator iterator; 4706 4707 BuiltinCandidateTypeSet(Sema &SemaRef) 4708 : HasNonRecordTypes(false), 4709 HasArithmeticOrEnumeralTypes(false), 4710 SemaRef(SemaRef), 4711 Context(SemaRef.Context) { } 4712 4713 void AddTypesConvertedFrom(QualType Ty, 4714 SourceLocation Loc, 4715 bool AllowUserConversions, 4716 bool AllowExplicitConversions, 4717 const Qualifiers &VisibleTypeConversionsQuals); 4718 4719 /// pointer_begin - First pointer type found; 4720 iterator pointer_begin() { return PointerTypes.begin(); } 4721 4722 /// pointer_end - Past the last pointer type found; 4723 iterator pointer_end() { return PointerTypes.end(); } 4724 4725 /// member_pointer_begin - First member pointer type found; 4726 iterator member_pointer_begin() { return MemberPointerTypes.begin(); } 4727 4728 /// member_pointer_end - Past the last member pointer type found; 4729 iterator member_pointer_end() { return MemberPointerTypes.end(); } 4730 4731 /// enumeration_begin - First enumeration type found; 4732 iterator enumeration_begin() { return EnumerationTypes.begin(); } 4733 4734 /// enumeration_end - Past the last enumeration type found; 4735 iterator enumeration_end() { return EnumerationTypes.end(); } 4736 4737 iterator vector_begin() { return VectorTypes.begin(); } 4738 iterator vector_end() { return VectorTypes.end(); } 4739 4740 bool hasNonRecordTypes() { return HasNonRecordTypes; } 4741 bool hasArithmeticOrEnumeralTypes() { return HasArithmeticOrEnumeralTypes; } 4742}; 4743 4744/// AddPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty to 4745/// the set of pointer types along with any more-qualified variants of 4746/// that type. For example, if @p Ty is "int const *", this routine 4747/// will add "int const *", "int const volatile *", "int const 4748/// restrict *", and "int const volatile restrict *" to the set of 4749/// pointer types. Returns true if the add of @p Ty itself succeeded, 4750/// false otherwise. 4751/// 4752/// FIXME: what to do about extended qualifiers? 4753bool 4754BuiltinCandidateTypeSet::AddPointerWithMoreQualifiedTypeVariants(QualType Ty, 4755 const Qualifiers &VisibleQuals) { 4756 4757 // Insert this type. 4758 if (!PointerTypes.insert(Ty)) 4759 return false; 4760 4761 QualType PointeeTy; 4762 const PointerType *PointerTy = Ty->getAs<PointerType>(); 4763 bool buildObjCPtr = false; 4764 if (!PointerTy) { 4765 if (const ObjCObjectPointerType *PTy = Ty->getAs<ObjCObjectPointerType>()) { 4766 PointeeTy = PTy->getPointeeType(); 4767 buildObjCPtr = true; 4768 } 4769 else 4770 assert(false && "type was not a pointer type!"); 4771 } 4772 else 4773 PointeeTy = PointerTy->getPointeeType(); 4774 4775 // Don't add qualified variants of arrays. For one, they're not allowed 4776 // (the qualifier would sink to the element type), and for another, the 4777 // only overload situation where it matters is subscript or pointer +- int, 4778 // and those shouldn't have qualifier variants anyway. 4779 if (PointeeTy->isArrayType()) 4780 return true; 4781 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 4782 if (const ConstantArrayType *Array =Context.getAsConstantArrayType(PointeeTy)) 4783 BaseCVR = Array->getElementType().getCVRQualifiers(); 4784 bool hasVolatile = VisibleQuals.hasVolatile(); 4785 bool hasRestrict = VisibleQuals.hasRestrict(); 4786 4787 // Iterate through all strict supersets of BaseCVR. 4788 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 4789 if ((CVR | BaseCVR) != CVR) continue; 4790 // Skip over Volatile/Restrict if no Volatile/Restrict found anywhere 4791 // in the types. 4792 if ((CVR & Qualifiers::Volatile) && !hasVolatile) continue; 4793 if ((CVR & Qualifiers::Restrict) && !hasRestrict) continue; 4794 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 4795 if (!buildObjCPtr) 4796 PointerTypes.insert(Context.getPointerType(QPointeeTy)); 4797 else 4798 PointerTypes.insert(Context.getObjCObjectPointerType(QPointeeTy)); 4799 } 4800 4801 return true; 4802} 4803 4804/// AddMemberPointerWithMoreQualifiedTypeVariants - Add the pointer type @p Ty 4805/// to the set of pointer types along with any more-qualified variants of 4806/// that type. For example, if @p Ty is "int const *", this routine 4807/// will add "int const *", "int const volatile *", "int const 4808/// restrict *", and "int const volatile restrict *" to the set of 4809/// pointer types. Returns true if the add of @p Ty itself succeeded, 4810/// false otherwise. 4811/// 4812/// FIXME: what to do about extended qualifiers? 4813bool 4814BuiltinCandidateTypeSet::AddMemberPointerWithMoreQualifiedTypeVariants( 4815 QualType Ty) { 4816 // Insert this type. 4817 if (!MemberPointerTypes.insert(Ty)) 4818 return false; 4819 4820 const MemberPointerType *PointerTy = Ty->getAs<MemberPointerType>(); 4821 assert(PointerTy && "type was not a member pointer type!"); 4822 4823 QualType PointeeTy = PointerTy->getPointeeType(); 4824 // Don't add qualified variants of arrays. For one, they're not allowed 4825 // (the qualifier would sink to the element type), and for another, the 4826 // only overload situation where it matters is subscript or pointer +- int, 4827 // and those shouldn't have qualifier variants anyway. 4828 if (PointeeTy->isArrayType()) 4829 return true; 4830 const Type *ClassTy = PointerTy->getClass(); 4831 4832 // Iterate through all strict supersets of the pointee type's CVR 4833 // qualifiers. 4834 unsigned BaseCVR = PointeeTy.getCVRQualifiers(); 4835 for (unsigned CVR = BaseCVR+1; CVR <= Qualifiers::CVRMask; ++CVR) { 4836 if ((CVR | BaseCVR) != CVR) continue; 4837 4838 QualType QPointeeTy = Context.getCVRQualifiedType(PointeeTy, CVR); 4839 MemberPointerTypes.insert( 4840 Context.getMemberPointerType(QPointeeTy, ClassTy)); 4841 } 4842 4843 return true; 4844} 4845 4846/// AddTypesConvertedFrom - Add each of the types to which the type @p 4847/// Ty can be implicit converted to the given set of @p Types. We're 4848/// primarily interested in pointer types and enumeration types. We also 4849/// take member pointer types, for the conditional operator. 4850/// AllowUserConversions is true if we should look at the conversion 4851/// functions of a class type, and AllowExplicitConversions if we 4852/// should also include the explicit conversion functions of a class 4853/// type. 4854void 4855BuiltinCandidateTypeSet::AddTypesConvertedFrom(QualType Ty, 4856 SourceLocation Loc, 4857 bool AllowUserConversions, 4858 bool AllowExplicitConversions, 4859 const Qualifiers &VisibleQuals) { 4860 // Only deal with canonical types. 4861 Ty = Context.getCanonicalType(Ty); 4862 4863 // Look through reference types; they aren't part of the type of an 4864 // expression for the purposes of conversions. 4865 if (const ReferenceType *RefTy = Ty->getAs<ReferenceType>()) 4866 Ty = RefTy->getPointeeType(); 4867 4868 // If we're dealing with an array type, decay to the pointer. 4869 if (Ty->isArrayType()) 4870 Ty = SemaRef.Context.getArrayDecayedType(Ty); 4871 4872 // Otherwise, we don't care about qualifiers on the type. 4873 Ty = Ty.getLocalUnqualifiedType(); 4874 4875 // Flag if we ever add a non-record type. 4876 const RecordType *TyRec = Ty->getAs<RecordType>(); 4877 HasNonRecordTypes = HasNonRecordTypes || !TyRec; 4878 4879 // Flag if we encounter an arithmetic type. 4880 HasArithmeticOrEnumeralTypes = 4881 HasArithmeticOrEnumeralTypes || Ty->isArithmeticType(); 4882 4883 if (Ty->isObjCIdType() || Ty->isObjCClassType()) 4884 PointerTypes.insert(Ty); 4885 else if (Ty->getAs<PointerType>() || Ty->getAs<ObjCObjectPointerType>()) { 4886 // Insert our type, and its more-qualified variants, into the set 4887 // of types. 4888 if (!AddPointerWithMoreQualifiedTypeVariants(Ty, VisibleQuals)) 4889 return; 4890 } else if (Ty->isMemberPointerType()) { 4891 // Member pointers are far easier, since the pointee can't be converted. 4892 if (!AddMemberPointerWithMoreQualifiedTypeVariants(Ty)) 4893 return; 4894 } else if (Ty->isEnumeralType()) { 4895 HasArithmeticOrEnumeralTypes = true; 4896 EnumerationTypes.insert(Ty); 4897 } else if (Ty->isVectorType()) { 4898 // We treat vector types as arithmetic types in many contexts as an 4899 // extension. 4900 HasArithmeticOrEnumeralTypes = true; 4901 VectorTypes.insert(Ty); 4902 } else if (AllowUserConversions && TyRec) { 4903 // No conversion functions in incomplete types. 4904 if (SemaRef.RequireCompleteType(Loc, Ty, 0)) 4905 return; 4906 4907 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 4908 const UnresolvedSetImpl *Conversions 4909 = ClassDecl->getVisibleConversionFunctions(); 4910 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 4911 E = Conversions->end(); I != E; ++I) { 4912 NamedDecl *D = I.getDecl(); 4913 if (isa<UsingShadowDecl>(D)) 4914 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 4915 4916 // Skip conversion function templates; they don't tell us anything 4917 // about which builtin types we can convert to. 4918 if (isa<FunctionTemplateDecl>(D)) 4919 continue; 4920 4921 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 4922 if (AllowExplicitConversions || !Conv->isExplicit()) { 4923 AddTypesConvertedFrom(Conv->getConversionType(), Loc, false, false, 4924 VisibleQuals); 4925 } 4926 } 4927 } 4928} 4929 4930/// \brief Helper function for AddBuiltinOperatorCandidates() that adds 4931/// the volatile- and non-volatile-qualified assignment operators for the 4932/// given type to the candidate set. 4933static void AddBuiltinAssignmentOperatorCandidates(Sema &S, 4934 QualType T, 4935 Expr **Args, 4936 unsigned NumArgs, 4937 OverloadCandidateSet &CandidateSet) { 4938 QualType ParamTypes[2]; 4939 4940 // T& operator=(T&, T) 4941 ParamTypes[0] = S.Context.getLValueReferenceType(T); 4942 ParamTypes[1] = T; 4943 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 4944 /*IsAssignmentOperator=*/true); 4945 4946 if (!S.Context.getCanonicalType(T).isVolatileQualified()) { 4947 // volatile T& operator=(volatile T&, T) 4948 ParamTypes[0] 4949 = S.Context.getLValueReferenceType(S.Context.getVolatileType(T)); 4950 ParamTypes[1] = T; 4951 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 4952 /*IsAssignmentOperator=*/true); 4953 } 4954} 4955 4956/// CollectVRQualifiers - This routine returns Volatile/Restrict qualifiers, 4957/// if any, found in visible type conversion functions found in ArgExpr's type. 4958static Qualifiers CollectVRQualifiers(ASTContext &Context, Expr* ArgExpr) { 4959 Qualifiers VRQuals; 4960 const RecordType *TyRec; 4961 if (const MemberPointerType *RHSMPType = 4962 ArgExpr->getType()->getAs<MemberPointerType>()) 4963 TyRec = RHSMPType->getClass()->getAs<RecordType>(); 4964 else 4965 TyRec = ArgExpr->getType()->getAs<RecordType>(); 4966 if (!TyRec) { 4967 // Just to be safe, assume the worst case. 4968 VRQuals.addVolatile(); 4969 VRQuals.addRestrict(); 4970 return VRQuals; 4971 } 4972 4973 CXXRecordDecl *ClassDecl = cast<CXXRecordDecl>(TyRec->getDecl()); 4974 if (!ClassDecl->hasDefinition()) 4975 return VRQuals; 4976 4977 const UnresolvedSetImpl *Conversions = 4978 ClassDecl->getVisibleConversionFunctions(); 4979 4980 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 4981 E = Conversions->end(); I != E; ++I) { 4982 NamedDecl *D = I.getDecl(); 4983 if (isa<UsingShadowDecl>(D)) 4984 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 4985 if (CXXConversionDecl *Conv = dyn_cast<CXXConversionDecl>(D)) { 4986 QualType CanTy = Context.getCanonicalType(Conv->getConversionType()); 4987 if (const ReferenceType *ResTypeRef = CanTy->getAs<ReferenceType>()) 4988 CanTy = ResTypeRef->getPointeeType(); 4989 // Need to go down the pointer/mempointer chain and add qualifiers 4990 // as see them. 4991 bool done = false; 4992 while (!done) { 4993 if (const PointerType *ResTypePtr = CanTy->getAs<PointerType>()) 4994 CanTy = ResTypePtr->getPointeeType(); 4995 else if (const MemberPointerType *ResTypeMPtr = 4996 CanTy->getAs<MemberPointerType>()) 4997 CanTy = ResTypeMPtr->getPointeeType(); 4998 else 4999 done = true; 5000 if (CanTy.isVolatileQualified()) 5001 VRQuals.addVolatile(); 5002 if (CanTy.isRestrictQualified()) 5003 VRQuals.addRestrict(); 5004 if (VRQuals.hasRestrict() && VRQuals.hasVolatile()) 5005 return VRQuals; 5006 } 5007 } 5008 } 5009 return VRQuals; 5010} 5011 5012namespace { 5013 5014/// \brief Helper class to manage the addition of builtin operator overload 5015/// candidates. It provides shared state and utility methods used throughout 5016/// the process, as well as a helper method to add each group of builtin 5017/// operator overloads from the standard to a candidate set. 5018class BuiltinOperatorOverloadBuilder { 5019 // Common instance state available to all overload candidate addition methods. 5020 Sema &S; 5021 Expr **Args; 5022 unsigned NumArgs; 5023 Qualifiers VisibleTypeConversionsQuals; 5024 bool HasArithmeticOrEnumeralCandidateType; 5025 llvm::SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes; 5026 OverloadCandidateSet &CandidateSet; 5027 5028 // Define some constants used to index and iterate over the arithemetic types 5029 // provided via the getArithmeticType() method below. 5030 // The "promoted arithmetic types" are the arithmetic 5031 // types are that preserved by promotion (C++ [over.built]p2). 5032 static const unsigned FirstIntegralType = 3; 5033 static const unsigned LastIntegralType = 18; 5034 static const unsigned FirstPromotedIntegralType = 3, 5035 LastPromotedIntegralType = 9; 5036 static const unsigned FirstPromotedArithmeticType = 0, 5037 LastPromotedArithmeticType = 9; 5038 static const unsigned NumArithmeticTypes = 18; 5039 5040 /// \brief Get the canonical type for a given arithmetic type index. 5041 CanQualType getArithmeticType(unsigned index) { 5042 assert(index < NumArithmeticTypes); 5043 static CanQualType ASTContext::* const 5044 ArithmeticTypes[NumArithmeticTypes] = { 5045 // Start of promoted types. 5046 &ASTContext::FloatTy, 5047 &ASTContext::DoubleTy, 5048 &ASTContext::LongDoubleTy, 5049 5050 // Start of integral types. 5051 &ASTContext::IntTy, 5052 &ASTContext::LongTy, 5053 &ASTContext::LongLongTy, 5054 &ASTContext::UnsignedIntTy, 5055 &ASTContext::UnsignedLongTy, 5056 &ASTContext::UnsignedLongLongTy, 5057 // End of promoted types. 5058 5059 &ASTContext::BoolTy, 5060 &ASTContext::CharTy, 5061 &ASTContext::WCharTy, 5062 &ASTContext::Char16Ty, 5063 &ASTContext::Char32Ty, 5064 &ASTContext::SignedCharTy, 5065 &ASTContext::ShortTy, 5066 &ASTContext::UnsignedCharTy, 5067 &ASTContext::UnsignedShortTy, 5068 // End of integral types. 5069 // FIXME: What about complex? 5070 }; 5071 return S.Context.*ArithmeticTypes[index]; 5072 } 5073 5074 /// \brief Gets the canonical type resulting from the usual arithemetic 5075 /// converions for the given arithmetic types. 5076 CanQualType getUsualArithmeticConversions(unsigned L, unsigned R) { 5077 // Accelerator table for performing the usual arithmetic conversions. 5078 // The rules are basically: 5079 // - if either is floating-point, use the wider floating-point 5080 // - if same signedness, use the higher rank 5081 // - if same size, use unsigned of the higher rank 5082 // - use the larger type 5083 // These rules, together with the axiom that higher ranks are 5084 // never smaller, are sufficient to precompute all of these results 5085 // *except* when dealing with signed types of higher rank. 5086 // (we could precompute SLL x UI for all known platforms, but it's 5087 // better not to make any assumptions). 5088 enum PromotedType { 5089 Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL, Dep=-1 5090 }; 5091 static PromotedType ConversionsTable[LastPromotedArithmeticType] 5092 [LastPromotedArithmeticType] = { 5093 /* Flt*/ { Flt, Dbl, LDbl, Flt, Flt, Flt, Flt, Flt, Flt }, 5094 /* Dbl*/ { Dbl, Dbl, LDbl, Dbl, Dbl, Dbl, Dbl, Dbl, Dbl }, 5095 /*LDbl*/ { LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl, LDbl }, 5096 /* SI*/ { Flt, Dbl, LDbl, SI, SL, SLL, UI, UL, ULL }, 5097 /* SL*/ { Flt, Dbl, LDbl, SL, SL, SLL, Dep, UL, ULL }, 5098 /* SLL*/ { Flt, Dbl, LDbl, SLL, SLL, SLL, Dep, Dep, ULL }, 5099 /* UI*/ { Flt, Dbl, LDbl, UI, Dep, Dep, UI, UL, ULL }, 5100 /* UL*/ { Flt, Dbl, LDbl, UL, UL, Dep, UL, UL, ULL }, 5101 /* ULL*/ { Flt, Dbl, LDbl, ULL, ULL, ULL, ULL, ULL, ULL }, 5102 }; 5103 5104 assert(L < LastPromotedArithmeticType); 5105 assert(R < LastPromotedArithmeticType); 5106 int Idx = ConversionsTable[L][R]; 5107 5108 // Fast path: the table gives us a concrete answer. 5109 if (Idx != Dep) return getArithmeticType(Idx); 5110 5111 // Slow path: we need to compare widths. 5112 // An invariant is that the signed type has higher rank. 5113 CanQualType LT = getArithmeticType(L), 5114 RT = getArithmeticType(R); 5115 unsigned LW = S.Context.getIntWidth(LT), 5116 RW = S.Context.getIntWidth(RT); 5117 5118 // If they're different widths, use the signed type. 5119 if (LW > RW) return LT; 5120 else if (LW < RW) return RT; 5121 5122 // Otherwise, use the unsigned type of the signed type's rank. 5123 if (L == SL || R == SL) return S.Context.UnsignedLongTy; 5124 assert(L == SLL || R == SLL); 5125 return S.Context.UnsignedLongLongTy; 5126 } 5127 5128 /// \brief Helper method to factor out the common pattern of adding overloads 5129 /// for '++' and '--' builtin operators. 5130 void addPlusPlusMinusMinusStyleOverloads(QualType CandidateTy, 5131 bool HasVolatile) { 5132 QualType ParamTypes[2] = { 5133 S.Context.getLValueReferenceType(CandidateTy), 5134 S.Context.IntTy 5135 }; 5136 5137 // Non-volatile version. 5138 if (NumArgs == 1) 5139 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5140 else 5141 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5142 5143 // Use a heuristic to reduce number of builtin candidates in the set: 5144 // add volatile version only if there are conversions to a volatile type. 5145 if (HasVolatile) { 5146 ParamTypes[0] = 5147 S.Context.getLValueReferenceType( 5148 S.Context.getVolatileType(CandidateTy)); 5149 if (NumArgs == 1) 5150 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 1, CandidateSet); 5151 else 5152 S.AddBuiltinCandidate(CandidateTy, ParamTypes, Args, 2, CandidateSet); 5153 } 5154 } 5155 5156public: 5157 BuiltinOperatorOverloadBuilder( 5158 Sema &S, Expr **Args, unsigned NumArgs, 5159 Qualifiers VisibleTypeConversionsQuals, 5160 bool HasArithmeticOrEnumeralCandidateType, 5161 llvm::SmallVectorImpl<BuiltinCandidateTypeSet> &CandidateTypes, 5162 OverloadCandidateSet &CandidateSet) 5163 : S(S), Args(Args), NumArgs(NumArgs), 5164 VisibleTypeConversionsQuals(VisibleTypeConversionsQuals), 5165 HasArithmeticOrEnumeralCandidateType( 5166 HasArithmeticOrEnumeralCandidateType), 5167 CandidateTypes(CandidateTypes), 5168 CandidateSet(CandidateSet) { 5169 // Validate some of our static helper constants in debug builds. 5170 assert(getArithmeticType(FirstPromotedIntegralType) == S.Context.IntTy && 5171 "Invalid first promoted integral type"); 5172 assert(getArithmeticType(LastPromotedIntegralType - 1) 5173 == S.Context.UnsignedLongLongTy && 5174 "Invalid last promoted integral type"); 5175 assert(getArithmeticType(FirstPromotedArithmeticType) 5176 == S.Context.FloatTy && 5177 "Invalid first promoted arithmetic type"); 5178 assert(getArithmeticType(LastPromotedArithmeticType - 1) 5179 == S.Context.UnsignedLongLongTy && 5180 "Invalid last promoted arithmetic type"); 5181 } 5182 5183 // C++ [over.built]p3: 5184 // 5185 // For every pair (T, VQ), where T is an arithmetic type, and VQ 5186 // is either volatile or empty, there exist candidate operator 5187 // functions of the form 5188 // 5189 // VQ T& operator++(VQ T&); 5190 // T operator++(VQ T&, int); 5191 // 5192 // C++ [over.built]p4: 5193 // 5194 // For every pair (T, VQ), where T is an arithmetic type other 5195 // than bool, and VQ is either volatile or empty, there exist 5196 // candidate operator functions of the form 5197 // 5198 // VQ T& operator--(VQ T&); 5199 // T operator--(VQ T&, int); 5200 void addPlusPlusMinusMinusArithmeticOverloads(OverloadedOperatorKind Op) { 5201 if (!HasArithmeticOrEnumeralCandidateType) 5202 return; 5203 5204 for (unsigned Arith = (Op == OO_PlusPlus? 0 : 1); 5205 Arith < NumArithmeticTypes; ++Arith) { 5206 addPlusPlusMinusMinusStyleOverloads( 5207 getArithmeticType(Arith), 5208 VisibleTypeConversionsQuals.hasVolatile()); 5209 } 5210 } 5211 5212 // C++ [over.built]p5: 5213 // 5214 // For every pair (T, VQ), where T is a cv-qualified or 5215 // cv-unqualified object type, and VQ is either volatile or 5216 // empty, there exist candidate operator functions of the form 5217 // 5218 // T*VQ& operator++(T*VQ&); 5219 // T*VQ& operator--(T*VQ&); 5220 // T* operator++(T*VQ&, int); 5221 // T* operator--(T*VQ&, int); 5222 void addPlusPlusMinusMinusPointerOverloads() { 5223 for (BuiltinCandidateTypeSet::iterator 5224 Ptr = CandidateTypes[0].pointer_begin(), 5225 PtrEnd = CandidateTypes[0].pointer_end(); 5226 Ptr != PtrEnd; ++Ptr) { 5227 // Skip pointer types that aren't pointers to object types. 5228 if (!(*Ptr)->getPointeeType()->isObjectType()) 5229 continue; 5230 5231 addPlusPlusMinusMinusStyleOverloads(*Ptr, 5232 (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5233 VisibleTypeConversionsQuals.hasVolatile())); 5234 } 5235 } 5236 5237 // C++ [over.built]p6: 5238 // For every cv-qualified or cv-unqualified object type T, there 5239 // exist candidate operator functions of the form 5240 // 5241 // T& operator*(T*); 5242 // 5243 // C++ [over.built]p7: 5244 // For every function type T that does not have cv-qualifiers or a 5245 // ref-qualifier, there exist candidate operator functions of the form 5246 // T& operator*(T*); 5247 void addUnaryStarPointerOverloads() { 5248 for (BuiltinCandidateTypeSet::iterator 5249 Ptr = CandidateTypes[0].pointer_begin(), 5250 PtrEnd = CandidateTypes[0].pointer_end(); 5251 Ptr != PtrEnd; ++Ptr) { 5252 QualType ParamTy = *Ptr; 5253 QualType PointeeTy = ParamTy->getPointeeType(); 5254 if (!PointeeTy->isObjectType() && !PointeeTy->isFunctionType()) 5255 continue; 5256 5257 if (const FunctionProtoType *Proto =PointeeTy->getAs<FunctionProtoType>()) 5258 if (Proto->getTypeQuals() || Proto->getRefQualifier()) 5259 continue; 5260 5261 S.AddBuiltinCandidate(S.Context.getLValueReferenceType(PointeeTy), 5262 &ParamTy, Args, 1, CandidateSet); 5263 } 5264 } 5265 5266 // C++ [over.built]p9: 5267 // For every promoted arithmetic type T, there exist candidate 5268 // operator functions of the form 5269 // 5270 // T operator+(T); 5271 // T operator-(T); 5272 void addUnaryPlusOrMinusArithmeticOverloads() { 5273 if (!HasArithmeticOrEnumeralCandidateType) 5274 return; 5275 5276 for (unsigned Arith = FirstPromotedArithmeticType; 5277 Arith < LastPromotedArithmeticType; ++Arith) { 5278 QualType ArithTy = getArithmeticType(Arith); 5279 S.AddBuiltinCandidate(ArithTy, &ArithTy, Args, 1, CandidateSet); 5280 } 5281 5282 // Extension: We also add these operators for vector types. 5283 for (BuiltinCandidateTypeSet::iterator 5284 Vec = CandidateTypes[0].vector_begin(), 5285 VecEnd = CandidateTypes[0].vector_end(); 5286 Vec != VecEnd; ++Vec) { 5287 QualType VecTy = *Vec; 5288 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5289 } 5290 } 5291 5292 // C++ [over.built]p8: 5293 // For every type T, there exist candidate operator functions of 5294 // the form 5295 // 5296 // T* operator+(T*); 5297 void addUnaryPlusPointerOverloads() { 5298 for (BuiltinCandidateTypeSet::iterator 5299 Ptr = CandidateTypes[0].pointer_begin(), 5300 PtrEnd = CandidateTypes[0].pointer_end(); 5301 Ptr != PtrEnd; ++Ptr) { 5302 QualType ParamTy = *Ptr; 5303 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet); 5304 } 5305 } 5306 5307 // C++ [over.built]p10: 5308 // For every promoted integral type T, there exist candidate 5309 // operator functions of the form 5310 // 5311 // T operator~(T); 5312 void addUnaryTildePromotedIntegralOverloads() { 5313 if (!HasArithmeticOrEnumeralCandidateType) 5314 return; 5315 5316 for (unsigned Int = FirstPromotedIntegralType; 5317 Int < LastPromotedIntegralType; ++Int) { 5318 QualType IntTy = getArithmeticType(Int); 5319 S.AddBuiltinCandidate(IntTy, &IntTy, Args, 1, CandidateSet); 5320 } 5321 5322 // Extension: We also add this operator for vector types. 5323 for (BuiltinCandidateTypeSet::iterator 5324 Vec = CandidateTypes[0].vector_begin(), 5325 VecEnd = CandidateTypes[0].vector_end(); 5326 Vec != VecEnd; ++Vec) { 5327 QualType VecTy = *Vec; 5328 S.AddBuiltinCandidate(VecTy, &VecTy, Args, 1, CandidateSet); 5329 } 5330 } 5331 5332 // C++ [over.match.oper]p16: 5333 // For every pointer to member type T, there exist candidate operator 5334 // functions of the form 5335 // 5336 // bool operator==(T,T); 5337 // bool operator!=(T,T); 5338 void addEqualEqualOrNotEqualMemberPointerOverloads() { 5339 /// Set of (canonical) types that we've already handled. 5340 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5341 5342 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5343 for (BuiltinCandidateTypeSet::iterator 5344 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5345 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5346 MemPtr != MemPtrEnd; 5347 ++MemPtr) { 5348 // Don't add the same builtin candidate twice. 5349 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5350 continue; 5351 5352 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 5353 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5354 CandidateSet); 5355 } 5356 } 5357 } 5358 5359 // C++ [over.built]p15: 5360 // 5361 // For every pointer or enumeration type T, there exist 5362 // candidate operator functions of the form 5363 // 5364 // bool operator<(T, T); 5365 // bool operator>(T, T); 5366 // bool operator<=(T, T); 5367 // bool operator>=(T, T); 5368 // bool operator==(T, T); 5369 // bool operator!=(T, T); 5370 void addRelationalPointerOrEnumeralOverloads() { 5371 // C++ [over.built]p1: 5372 // If there is a user-written candidate with the same name and parameter 5373 // types as a built-in candidate operator function, the built-in operator 5374 // function is hidden and is not included in the set of candidate 5375 // functions. 5376 // 5377 // The text is actually in a note, but if we don't implement it then we end 5378 // up with ambiguities when the user provides an overloaded operator for 5379 // an enumeration type. Note that only enumeration types have this problem, 5380 // so we track which enumeration types we've seen operators for. Also, the 5381 // only other overloaded operator with enumeration argumenst, operator=, 5382 // cannot be overloaded for enumeration types, so this is the only place 5383 // where we must suppress candidates like this. 5384 llvm::DenseSet<std::pair<CanQualType, CanQualType> > 5385 UserDefinedBinaryOperators; 5386 5387 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5388 if (CandidateTypes[ArgIdx].enumeration_begin() != 5389 CandidateTypes[ArgIdx].enumeration_end()) { 5390 for (OverloadCandidateSet::iterator C = CandidateSet.begin(), 5391 CEnd = CandidateSet.end(); 5392 C != CEnd; ++C) { 5393 if (!C->Viable || !C->Function || C->Function->getNumParams() != 2) 5394 continue; 5395 5396 QualType FirstParamType = 5397 C->Function->getParamDecl(0)->getType().getUnqualifiedType(); 5398 QualType SecondParamType = 5399 C->Function->getParamDecl(1)->getType().getUnqualifiedType(); 5400 5401 // Skip if either parameter isn't of enumeral type. 5402 if (!FirstParamType->isEnumeralType() || 5403 !SecondParamType->isEnumeralType()) 5404 continue; 5405 5406 // Add this operator to the set of known user-defined operators. 5407 UserDefinedBinaryOperators.insert( 5408 std::make_pair(S.Context.getCanonicalType(FirstParamType), 5409 S.Context.getCanonicalType(SecondParamType))); 5410 } 5411 } 5412 } 5413 5414 /// Set of (canonical) types that we've already handled. 5415 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5416 5417 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 5418 for (BuiltinCandidateTypeSet::iterator 5419 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 5420 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 5421 Ptr != PtrEnd; ++Ptr) { 5422 // Don't add the same builtin candidate twice. 5423 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5424 continue; 5425 5426 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5427 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5428 CandidateSet); 5429 } 5430 for (BuiltinCandidateTypeSet::iterator 5431 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5432 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5433 Enum != EnumEnd; ++Enum) { 5434 CanQualType CanonType = S.Context.getCanonicalType(*Enum); 5435 5436 // Don't add the same builtin candidate twice, or if a user defined 5437 // candidate exists. 5438 if (!AddedTypes.insert(CanonType) || 5439 UserDefinedBinaryOperators.count(std::make_pair(CanonType, 5440 CanonType))) 5441 continue; 5442 5443 QualType ParamTypes[2] = { *Enum, *Enum }; 5444 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, 5445 CandidateSet); 5446 } 5447 } 5448 } 5449 5450 // C++ [over.built]p13: 5451 // 5452 // For every cv-qualified or cv-unqualified object type T 5453 // there exist candidate operator functions of the form 5454 // 5455 // T* operator+(T*, ptrdiff_t); 5456 // T& operator[](T*, ptrdiff_t); [BELOW] 5457 // T* operator-(T*, ptrdiff_t); 5458 // T* operator+(ptrdiff_t, T*); 5459 // T& operator[](ptrdiff_t, T*); [BELOW] 5460 // 5461 // C++ [over.built]p14: 5462 // 5463 // For every T, where T is a pointer to object type, there 5464 // exist candidate operator functions of the form 5465 // 5466 // ptrdiff_t operator-(T, T); 5467 void addBinaryPlusOrMinusPointerOverloads(OverloadedOperatorKind Op) { 5468 /// Set of (canonical) types that we've already handled. 5469 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5470 5471 for (int Arg = 0; Arg < 2; ++Arg) { 5472 QualType AsymetricParamTypes[2] = { 5473 S.Context.getPointerDiffType(), 5474 S.Context.getPointerDiffType(), 5475 }; 5476 for (BuiltinCandidateTypeSet::iterator 5477 Ptr = CandidateTypes[Arg].pointer_begin(), 5478 PtrEnd = CandidateTypes[Arg].pointer_end(); 5479 Ptr != PtrEnd; ++Ptr) { 5480 QualType PointeeTy = (*Ptr)->getPointeeType(); 5481 if (!PointeeTy->isObjectType()) 5482 continue; 5483 5484 AsymetricParamTypes[Arg] = *Ptr; 5485 if (Arg == 0 || Op == OO_Plus) { 5486 // operator+(T*, ptrdiff_t) or operator-(T*, ptrdiff_t) 5487 // T* operator+(ptrdiff_t, T*); 5488 S.AddBuiltinCandidate(*Ptr, AsymetricParamTypes, Args, 2, 5489 CandidateSet); 5490 } 5491 if (Op == OO_Minus) { 5492 // ptrdiff_t operator-(T, T); 5493 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5494 continue; 5495 5496 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5497 S.AddBuiltinCandidate(S.Context.getPointerDiffType(), ParamTypes, 5498 Args, 2, CandidateSet); 5499 } 5500 } 5501 } 5502 } 5503 5504 // C++ [over.built]p12: 5505 // 5506 // For every pair of promoted arithmetic types L and R, there 5507 // exist candidate operator functions of the form 5508 // 5509 // LR operator*(L, R); 5510 // LR operator/(L, R); 5511 // LR operator+(L, R); 5512 // LR operator-(L, R); 5513 // bool operator<(L, R); 5514 // bool operator>(L, R); 5515 // bool operator<=(L, R); 5516 // bool operator>=(L, R); 5517 // bool operator==(L, R); 5518 // bool operator!=(L, R); 5519 // 5520 // where LR is the result of the usual arithmetic conversions 5521 // between types L and R. 5522 // 5523 // C++ [over.built]p24: 5524 // 5525 // For every pair of promoted arithmetic types L and R, there exist 5526 // candidate operator functions of the form 5527 // 5528 // LR operator?(bool, L, R); 5529 // 5530 // where LR is the result of the usual arithmetic conversions 5531 // between types L and R. 5532 // Our candidates ignore the first parameter. 5533 void addGenericBinaryArithmeticOverloads(bool isComparison) { 5534 if (!HasArithmeticOrEnumeralCandidateType) 5535 return; 5536 5537 for (unsigned Left = FirstPromotedArithmeticType; 5538 Left < LastPromotedArithmeticType; ++Left) { 5539 for (unsigned Right = FirstPromotedArithmeticType; 5540 Right < LastPromotedArithmeticType; ++Right) { 5541 QualType LandR[2] = { getArithmeticType(Left), 5542 getArithmeticType(Right) }; 5543 QualType Result = 5544 isComparison ? S.Context.BoolTy 5545 : getUsualArithmeticConversions(Left, Right); 5546 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5547 } 5548 } 5549 5550 // Extension: Add the binary operators ==, !=, <, <=, >=, >, *, /, and the 5551 // conditional operator for vector types. 5552 for (BuiltinCandidateTypeSet::iterator 5553 Vec1 = CandidateTypes[0].vector_begin(), 5554 Vec1End = CandidateTypes[0].vector_end(); 5555 Vec1 != Vec1End; ++Vec1) { 5556 for (BuiltinCandidateTypeSet::iterator 5557 Vec2 = CandidateTypes[1].vector_begin(), 5558 Vec2End = CandidateTypes[1].vector_end(); 5559 Vec2 != Vec2End; ++Vec2) { 5560 QualType LandR[2] = { *Vec1, *Vec2 }; 5561 QualType Result = S.Context.BoolTy; 5562 if (!isComparison) { 5563 if ((*Vec1)->isExtVectorType() || !(*Vec2)->isExtVectorType()) 5564 Result = *Vec1; 5565 else 5566 Result = *Vec2; 5567 } 5568 5569 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5570 } 5571 } 5572 } 5573 5574 // C++ [over.built]p17: 5575 // 5576 // For every pair of promoted integral types L and R, there 5577 // exist candidate operator functions of the form 5578 // 5579 // LR operator%(L, R); 5580 // LR operator&(L, R); 5581 // LR operator^(L, R); 5582 // LR operator|(L, R); 5583 // L operator<<(L, R); 5584 // L operator>>(L, R); 5585 // 5586 // where LR is the result of the usual arithmetic conversions 5587 // between types L and R. 5588 void addBinaryBitwiseArithmeticOverloads(OverloadedOperatorKind Op) { 5589 if (!HasArithmeticOrEnumeralCandidateType) 5590 return; 5591 5592 for (unsigned Left = FirstPromotedIntegralType; 5593 Left < LastPromotedIntegralType; ++Left) { 5594 for (unsigned Right = FirstPromotedIntegralType; 5595 Right < LastPromotedIntegralType; ++Right) { 5596 QualType LandR[2] = { getArithmeticType(Left), 5597 getArithmeticType(Right) }; 5598 QualType Result = (Op == OO_LessLess || Op == OO_GreaterGreater) 5599 ? LandR[0] 5600 : getUsualArithmeticConversions(Left, Right); 5601 S.AddBuiltinCandidate(Result, LandR, Args, 2, CandidateSet); 5602 } 5603 } 5604 } 5605 5606 // C++ [over.built]p20: 5607 // 5608 // For every pair (T, VQ), where T is an enumeration or 5609 // pointer to member type and VQ is either volatile or 5610 // empty, there exist candidate operator functions of the form 5611 // 5612 // VQ T& operator=(VQ T&, T); 5613 void addAssignmentMemberPointerOrEnumeralOverloads() { 5614 /// Set of (canonical) types that we've already handled. 5615 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5616 5617 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 5618 for (BuiltinCandidateTypeSet::iterator 5619 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5620 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5621 Enum != EnumEnd; ++Enum) { 5622 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 5623 continue; 5624 5625 AddBuiltinAssignmentOperatorCandidates(S, *Enum, Args, 2, 5626 CandidateSet); 5627 } 5628 5629 for (BuiltinCandidateTypeSet::iterator 5630 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5631 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5632 MemPtr != MemPtrEnd; ++MemPtr) { 5633 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5634 continue; 5635 5636 AddBuiltinAssignmentOperatorCandidates(S, *MemPtr, Args, 2, 5637 CandidateSet); 5638 } 5639 } 5640 } 5641 5642 // C++ [over.built]p19: 5643 // 5644 // For every pair (T, VQ), where T is any type and VQ is either 5645 // volatile or empty, there exist candidate operator functions 5646 // of the form 5647 // 5648 // T*VQ& operator=(T*VQ&, T*); 5649 // 5650 // C++ [over.built]p21: 5651 // 5652 // For every pair (T, VQ), where T is a cv-qualified or 5653 // cv-unqualified object type and VQ is either volatile or 5654 // empty, there exist candidate operator functions of the form 5655 // 5656 // T*VQ& operator+=(T*VQ&, ptrdiff_t); 5657 // T*VQ& operator-=(T*VQ&, ptrdiff_t); 5658 void addAssignmentPointerOverloads(bool isEqualOp) { 5659 /// Set of (canonical) types that we've already handled. 5660 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5661 5662 for (BuiltinCandidateTypeSet::iterator 5663 Ptr = CandidateTypes[0].pointer_begin(), 5664 PtrEnd = CandidateTypes[0].pointer_end(); 5665 Ptr != PtrEnd; ++Ptr) { 5666 // If this is operator=, keep track of the builtin candidates we added. 5667 if (isEqualOp) 5668 AddedTypes.insert(S.Context.getCanonicalType(*Ptr)); 5669 else if (!(*Ptr)->getPointeeType()->isObjectType()) 5670 continue; 5671 5672 // non-volatile version 5673 QualType ParamTypes[2] = { 5674 S.Context.getLValueReferenceType(*Ptr), 5675 isEqualOp ? *Ptr : S.Context.getPointerDiffType(), 5676 }; 5677 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5678 /*IsAssigmentOperator=*/ isEqualOp); 5679 5680 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5681 VisibleTypeConversionsQuals.hasVolatile()) { 5682 // volatile version 5683 ParamTypes[0] = 5684 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 5685 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5686 /*IsAssigmentOperator=*/isEqualOp); 5687 } 5688 } 5689 5690 if (isEqualOp) { 5691 for (BuiltinCandidateTypeSet::iterator 5692 Ptr = CandidateTypes[1].pointer_begin(), 5693 PtrEnd = CandidateTypes[1].pointer_end(); 5694 Ptr != PtrEnd; ++Ptr) { 5695 // Make sure we don't add the same candidate twice. 5696 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5697 continue; 5698 5699 QualType ParamTypes[2] = { 5700 S.Context.getLValueReferenceType(*Ptr), 5701 *Ptr, 5702 }; 5703 5704 // non-volatile version 5705 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5706 /*IsAssigmentOperator=*/true); 5707 5708 if (!S.Context.getCanonicalType(*Ptr).isVolatileQualified() && 5709 VisibleTypeConversionsQuals.hasVolatile()) { 5710 // volatile version 5711 ParamTypes[0] = 5712 S.Context.getLValueReferenceType(S.Context.getVolatileType(*Ptr)); 5713 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5714 CandidateSet, /*IsAssigmentOperator=*/true); 5715 } 5716 } 5717 } 5718 } 5719 5720 // C++ [over.built]p18: 5721 // 5722 // For every triple (L, VQ, R), where L is an arithmetic type, 5723 // VQ is either volatile or empty, and R is a promoted 5724 // arithmetic type, there exist candidate operator functions of 5725 // the form 5726 // 5727 // VQ L& operator=(VQ L&, R); 5728 // VQ L& operator*=(VQ L&, R); 5729 // VQ L& operator/=(VQ L&, R); 5730 // VQ L& operator+=(VQ L&, R); 5731 // VQ L& operator-=(VQ L&, R); 5732 void addAssignmentArithmeticOverloads(bool isEqualOp) { 5733 if (!HasArithmeticOrEnumeralCandidateType) 5734 return; 5735 5736 for (unsigned Left = 0; Left < NumArithmeticTypes; ++Left) { 5737 for (unsigned Right = FirstPromotedArithmeticType; 5738 Right < LastPromotedArithmeticType; ++Right) { 5739 QualType ParamTypes[2]; 5740 ParamTypes[1] = getArithmeticType(Right); 5741 5742 // Add this built-in operator as a candidate (VQ is empty). 5743 ParamTypes[0] = 5744 S.Context.getLValueReferenceType(getArithmeticType(Left)); 5745 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5746 /*IsAssigmentOperator=*/isEqualOp); 5747 5748 // Add this built-in operator as a candidate (VQ is 'volatile'). 5749 if (VisibleTypeConversionsQuals.hasVolatile()) { 5750 ParamTypes[0] = 5751 S.Context.getVolatileType(getArithmeticType(Left)); 5752 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 5753 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5754 CandidateSet, 5755 /*IsAssigmentOperator=*/isEqualOp); 5756 } 5757 } 5758 } 5759 5760 // Extension: Add the binary operators =, +=, -=, *=, /= for vector types. 5761 for (BuiltinCandidateTypeSet::iterator 5762 Vec1 = CandidateTypes[0].vector_begin(), 5763 Vec1End = CandidateTypes[0].vector_end(); 5764 Vec1 != Vec1End; ++Vec1) { 5765 for (BuiltinCandidateTypeSet::iterator 5766 Vec2 = CandidateTypes[1].vector_begin(), 5767 Vec2End = CandidateTypes[1].vector_end(); 5768 Vec2 != Vec2End; ++Vec2) { 5769 QualType ParamTypes[2]; 5770 ParamTypes[1] = *Vec2; 5771 // Add this built-in operator as a candidate (VQ is empty). 5772 ParamTypes[0] = S.Context.getLValueReferenceType(*Vec1); 5773 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet, 5774 /*IsAssigmentOperator=*/isEqualOp); 5775 5776 // Add this built-in operator as a candidate (VQ is 'volatile'). 5777 if (VisibleTypeConversionsQuals.hasVolatile()) { 5778 ParamTypes[0] = S.Context.getVolatileType(*Vec1); 5779 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 5780 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5781 CandidateSet, 5782 /*IsAssigmentOperator=*/isEqualOp); 5783 } 5784 } 5785 } 5786 } 5787 5788 // C++ [over.built]p22: 5789 // 5790 // For every triple (L, VQ, R), where L is an integral type, VQ 5791 // is either volatile or empty, and R is a promoted integral 5792 // type, there exist candidate operator functions of the form 5793 // 5794 // VQ L& operator%=(VQ L&, R); 5795 // VQ L& operator<<=(VQ L&, R); 5796 // VQ L& operator>>=(VQ L&, R); 5797 // VQ L& operator&=(VQ L&, R); 5798 // VQ L& operator^=(VQ L&, R); 5799 // VQ L& operator|=(VQ L&, R); 5800 void addAssignmentIntegralOverloads() { 5801 if (!HasArithmeticOrEnumeralCandidateType) 5802 return; 5803 5804 for (unsigned Left = FirstIntegralType; Left < LastIntegralType; ++Left) { 5805 for (unsigned Right = FirstPromotedIntegralType; 5806 Right < LastPromotedIntegralType; ++Right) { 5807 QualType ParamTypes[2]; 5808 ParamTypes[1] = getArithmeticType(Right); 5809 5810 // Add this built-in operator as a candidate (VQ is empty). 5811 ParamTypes[0] = 5812 S.Context.getLValueReferenceType(getArithmeticType(Left)); 5813 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, CandidateSet); 5814 if (VisibleTypeConversionsQuals.hasVolatile()) { 5815 // Add this built-in operator as a candidate (VQ is 'volatile'). 5816 ParamTypes[0] = getArithmeticType(Left); 5817 ParamTypes[0] = S.Context.getVolatileType(ParamTypes[0]); 5818 ParamTypes[0] = S.Context.getLValueReferenceType(ParamTypes[0]); 5819 S.AddBuiltinCandidate(ParamTypes[0], ParamTypes, Args, 2, 5820 CandidateSet); 5821 } 5822 } 5823 } 5824 } 5825 5826 // C++ [over.operator]p23: 5827 // 5828 // There also exist candidate operator functions of the form 5829 // 5830 // bool operator!(bool); 5831 // bool operator&&(bool, bool); 5832 // bool operator||(bool, bool); 5833 void addExclaimOverload() { 5834 QualType ParamTy = S.Context.BoolTy; 5835 S.AddBuiltinCandidate(ParamTy, &ParamTy, Args, 1, CandidateSet, 5836 /*IsAssignmentOperator=*/false, 5837 /*NumContextualBoolArguments=*/1); 5838 } 5839 void addAmpAmpOrPipePipeOverload() { 5840 QualType ParamTypes[2] = { S.Context.BoolTy, S.Context.BoolTy }; 5841 S.AddBuiltinCandidate(S.Context.BoolTy, ParamTypes, Args, 2, CandidateSet, 5842 /*IsAssignmentOperator=*/false, 5843 /*NumContextualBoolArguments=*/2); 5844 } 5845 5846 // C++ [over.built]p13: 5847 // 5848 // For every cv-qualified or cv-unqualified object type T there 5849 // exist candidate operator functions of the form 5850 // 5851 // T* operator+(T*, ptrdiff_t); [ABOVE] 5852 // T& operator[](T*, ptrdiff_t); 5853 // T* operator-(T*, ptrdiff_t); [ABOVE] 5854 // T* operator+(ptrdiff_t, T*); [ABOVE] 5855 // T& operator[](ptrdiff_t, T*); 5856 void addSubscriptOverloads() { 5857 for (BuiltinCandidateTypeSet::iterator 5858 Ptr = CandidateTypes[0].pointer_begin(), 5859 PtrEnd = CandidateTypes[0].pointer_end(); 5860 Ptr != PtrEnd; ++Ptr) { 5861 QualType ParamTypes[2] = { *Ptr, S.Context.getPointerDiffType() }; 5862 QualType PointeeType = (*Ptr)->getPointeeType(); 5863 if (!PointeeType->isObjectType()) 5864 continue; 5865 5866 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 5867 5868 // T& operator[](T*, ptrdiff_t) 5869 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 5870 } 5871 5872 for (BuiltinCandidateTypeSet::iterator 5873 Ptr = CandidateTypes[1].pointer_begin(), 5874 PtrEnd = CandidateTypes[1].pointer_end(); 5875 Ptr != PtrEnd; ++Ptr) { 5876 QualType ParamTypes[2] = { S.Context.getPointerDiffType(), *Ptr }; 5877 QualType PointeeType = (*Ptr)->getPointeeType(); 5878 if (!PointeeType->isObjectType()) 5879 continue; 5880 5881 QualType ResultTy = S.Context.getLValueReferenceType(PointeeType); 5882 5883 // T& operator[](ptrdiff_t, T*) 5884 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 5885 } 5886 } 5887 5888 // C++ [over.built]p11: 5889 // For every quintuple (C1, C2, T, CV1, CV2), where C2 is a class type, 5890 // C1 is the same type as C2 or is a derived class of C2, T is an object 5891 // type or a function type, and CV1 and CV2 are cv-qualifier-seqs, 5892 // there exist candidate operator functions of the form 5893 // 5894 // CV12 T& operator->*(CV1 C1*, CV2 T C2::*); 5895 // 5896 // where CV12 is the union of CV1 and CV2. 5897 void addArrowStarOverloads() { 5898 for (BuiltinCandidateTypeSet::iterator 5899 Ptr = CandidateTypes[0].pointer_begin(), 5900 PtrEnd = CandidateTypes[0].pointer_end(); 5901 Ptr != PtrEnd; ++Ptr) { 5902 QualType C1Ty = (*Ptr); 5903 QualType C1; 5904 QualifierCollector Q1; 5905 C1 = QualType(Q1.strip(C1Ty->getPointeeType()), 0); 5906 if (!isa<RecordType>(C1)) 5907 continue; 5908 // heuristic to reduce number of builtin candidates in the set. 5909 // Add volatile/restrict version only if there are conversions to a 5910 // volatile/restrict type. 5911 if (!VisibleTypeConversionsQuals.hasVolatile() && Q1.hasVolatile()) 5912 continue; 5913 if (!VisibleTypeConversionsQuals.hasRestrict() && Q1.hasRestrict()) 5914 continue; 5915 for (BuiltinCandidateTypeSet::iterator 5916 MemPtr = CandidateTypes[1].member_pointer_begin(), 5917 MemPtrEnd = CandidateTypes[1].member_pointer_end(); 5918 MemPtr != MemPtrEnd; ++MemPtr) { 5919 const MemberPointerType *mptr = cast<MemberPointerType>(*MemPtr); 5920 QualType C2 = QualType(mptr->getClass(), 0); 5921 C2 = C2.getUnqualifiedType(); 5922 if (C1 != C2 && !S.IsDerivedFrom(C1, C2)) 5923 break; 5924 QualType ParamTypes[2] = { *Ptr, *MemPtr }; 5925 // build CV12 T& 5926 QualType T = mptr->getPointeeType(); 5927 if (!VisibleTypeConversionsQuals.hasVolatile() && 5928 T.isVolatileQualified()) 5929 continue; 5930 if (!VisibleTypeConversionsQuals.hasRestrict() && 5931 T.isRestrictQualified()) 5932 continue; 5933 T = Q1.apply(S.Context, T); 5934 QualType ResultTy = S.Context.getLValueReferenceType(T); 5935 S.AddBuiltinCandidate(ResultTy, ParamTypes, Args, 2, CandidateSet); 5936 } 5937 } 5938 } 5939 5940 // Note that we don't consider the first argument, since it has been 5941 // contextually converted to bool long ago. The candidates below are 5942 // therefore added as binary. 5943 // 5944 // C++ [over.built]p25: 5945 // For every type T, where T is a pointer, pointer-to-member, or scoped 5946 // enumeration type, there exist candidate operator functions of the form 5947 // 5948 // T operator?(bool, T, T); 5949 // 5950 void addConditionalOperatorOverloads() { 5951 /// Set of (canonical) types that we've already handled. 5952 llvm::SmallPtrSet<QualType, 8> AddedTypes; 5953 5954 for (unsigned ArgIdx = 0; ArgIdx < 2; ++ArgIdx) { 5955 for (BuiltinCandidateTypeSet::iterator 5956 Ptr = CandidateTypes[ArgIdx].pointer_begin(), 5957 PtrEnd = CandidateTypes[ArgIdx].pointer_end(); 5958 Ptr != PtrEnd; ++Ptr) { 5959 if (!AddedTypes.insert(S.Context.getCanonicalType(*Ptr))) 5960 continue; 5961 5962 QualType ParamTypes[2] = { *Ptr, *Ptr }; 5963 S.AddBuiltinCandidate(*Ptr, ParamTypes, Args, 2, CandidateSet); 5964 } 5965 5966 for (BuiltinCandidateTypeSet::iterator 5967 MemPtr = CandidateTypes[ArgIdx].member_pointer_begin(), 5968 MemPtrEnd = CandidateTypes[ArgIdx].member_pointer_end(); 5969 MemPtr != MemPtrEnd; ++MemPtr) { 5970 if (!AddedTypes.insert(S.Context.getCanonicalType(*MemPtr))) 5971 continue; 5972 5973 QualType ParamTypes[2] = { *MemPtr, *MemPtr }; 5974 S.AddBuiltinCandidate(*MemPtr, ParamTypes, Args, 2, CandidateSet); 5975 } 5976 5977 if (S.getLangOptions().CPlusPlus0x) { 5978 for (BuiltinCandidateTypeSet::iterator 5979 Enum = CandidateTypes[ArgIdx].enumeration_begin(), 5980 EnumEnd = CandidateTypes[ArgIdx].enumeration_end(); 5981 Enum != EnumEnd; ++Enum) { 5982 if (!(*Enum)->getAs<EnumType>()->getDecl()->isScoped()) 5983 continue; 5984 5985 if (!AddedTypes.insert(S.Context.getCanonicalType(*Enum))) 5986 continue; 5987 5988 QualType ParamTypes[2] = { *Enum, *Enum }; 5989 S.AddBuiltinCandidate(*Enum, ParamTypes, Args, 2, CandidateSet); 5990 } 5991 } 5992 } 5993 } 5994}; 5995 5996} // end anonymous namespace 5997 5998/// AddBuiltinOperatorCandidates - Add the appropriate built-in 5999/// operator overloads to the candidate set (C++ [over.built]), based 6000/// on the operator @p Op and the arguments given. For example, if the 6001/// operator is a binary '+', this routine might add "int 6002/// operator+(int, int)" to cover integer addition. 6003void 6004Sema::AddBuiltinOperatorCandidates(OverloadedOperatorKind Op, 6005 SourceLocation OpLoc, 6006 Expr **Args, unsigned NumArgs, 6007 OverloadCandidateSet& CandidateSet) { 6008 // Find all of the types that the arguments can convert to, but only 6009 // if the operator we're looking at has built-in operator candidates 6010 // that make use of these types. Also record whether we encounter non-record 6011 // candidate types or either arithmetic or enumeral candidate types. 6012 Qualifiers VisibleTypeConversionsQuals; 6013 VisibleTypeConversionsQuals.addConst(); 6014 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 6015 VisibleTypeConversionsQuals += CollectVRQualifiers(Context, Args[ArgIdx]); 6016 6017 bool HasNonRecordCandidateType = false; 6018 bool HasArithmeticOrEnumeralCandidateType = false; 6019 llvm::SmallVector<BuiltinCandidateTypeSet, 2> CandidateTypes; 6020 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) { 6021 CandidateTypes.push_back(BuiltinCandidateTypeSet(*this)); 6022 CandidateTypes[ArgIdx].AddTypesConvertedFrom(Args[ArgIdx]->getType(), 6023 OpLoc, 6024 true, 6025 (Op == OO_Exclaim || 6026 Op == OO_AmpAmp || 6027 Op == OO_PipePipe), 6028 VisibleTypeConversionsQuals); 6029 HasNonRecordCandidateType = HasNonRecordCandidateType || 6030 CandidateTypes[ArgIdx].hasNonRecordTypes(); 6031 HasArithmeticOrEnumeralCandidateType = 6032 HasArithmeticOrEnumeralCandidateType || 6033 CandidateTypes[ArgIdx].hasArithmeticOrEnumeralTypes(); 6034 } 6035 6036 // Exit early when no non-record types have been added to the candidate set 6037 // for any of the arguments to the operator. 6038 if (!HasNonRecordCandidateType) 6039 return; 6040 6041 // Setup an object to manage the common state for building overloads. 6042 BuiltinOperatorOverloadBuilder OpBuilder(*this, Args, NumArgs, 6043 VisibleTypeConversionsQuals, 6044 HasArithmeticOrEnumeralCandidateType, 6045 CandidateTypes, CandidateSet); 6046 6047 // Dispatch over the operation to add in only those overloads which apply. 6048 switch (Op) { 6049 case OO_None: 6050 case NUM_OVERLOADED_OPERATORS: 6051 assert(false && "Expected an overloaded operator"); 6052 break; 6053 6054 case OO_New: 6055 case OO_Delete: 6056 case OO_Array_New: 6057 case OO_Array_Delete: 6058 case OO_Call: 6059 assert(false && "Special operators don't use AddBuiltinOperatorCandidates"); 6060 break; 6061 6062 case OO_Comma: 6063 case OO_Arrow: 6064 // C++ [over.match.oper]p3: 6065 // -- For the operator ',', the unary operator '&', or the 6066 // operator '->', the built-in candidates set is empty. 6067 break; 6068 6069 case OO_Plus: // '+' is either unary or binary 6070 if (NumArgs == 1) 6071 OpBuilder.addUnaryPlusPointerOverloads(); 6072 // Fall through. 6073 6074 case OO_Minus: // '-' is either unary or binary 6075 if (NumArgs == 1) { 6076 OpBuilder.addUnaryPlusOrMinusArithmeticOverloads(); 6077 } else { 6078 OpBuilder.addBinaryPlusOrMinusPointerOverloads(Op); 6079 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6080 } 6081 break; 6082 6083 case OO_Star: // '*' is either unary or binary 6084 if (NumArgs == 1) 6085 OpBuilder.addUnaryStarPointerOverloads(); 6086 else 6087 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6088 break; 6089 6090 case OO_Slash: 6091 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6092 break; 6093 6094 case OO_PlusPlus: 6095 case OO_MinusMinus: 6096 OpBuilder.addPlusPlusMinusMinusArithmeticOverloads(Op); 6097 OpBuilder.addPlusPlusMinusMinusPointerOverloads(); 6098 break; 6099 6100 case OO_EqualEqual: 6101 case OO_ExclaimEqual: 6102 OpBuilder.addEqualEqualOrNotEqualMemberPointerOverloads(); 6103 // Fall through. 6104 6105 case OO_Less: 6106 case OO_Greater: 6107 case OO_LessEqual: 6108 case OO_GreaterEqual: 6109 OpBuilder.addRelationalPointerOrEnumeralOverloads(); 6110 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/true); 6111 break; 6112 6113 case OO_Percent: 6114 case OO_Caret: 6115 case OO_Pipe: 6116 case OO_LessLess: 6117 case OO_GreaterGreater: 6118 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6119 break; 6120 6121 case OO_Amp: // '&' is either unary or binary 6122 if (NumArgs == 1) 6123 // C++ [over.match.oper]p3: 6124 // -- For the operator ',', the unary operator '&', or the 6125 // operator '->', the built-in candidates set is empty. 6126 break; 6127 6128 OpBuilder.addBinaryBitwiseArithmeticOverloads(Op); 6129 break; 6130 6131 case OO_Tilde: 6132 OpBuilder.addUnaryTildePromotedIntegralOverloads(); 6133 break; 6134 6135 case OO_Equal: 6136 OpBuilder.addAssignmentMemberPointerOrEnumeralOverloads(); 6137 // Fall through. 6138 6139 case OO_PlusEqual: 6140 case OO_MinusEqual: 6141 OpBuilder.addAssignmentPointerOverloads(Op == OO_Equal); 6142 // Fall through. 6143 6144 case OO_StarEqual: 6145 case OO_SlashEqual: 6146 OpBuilder.addAssignmentArithmeticOverloads(Op == OO_Equal); 6147 break; 6148 6149 case OO_PercentEqual: 6150 case OO_LessLessEqual: 6151 case OO_GreaterGreaterEqual: 6152 case OO_AmpEqual: 6153 case OO_CaretEqual: 6154 case OO_PipeEqual: 6155 OpBuilder.addAssignmentIntegralOverloads(); 6156 break; 6157 6158 case OO_Exclaim: 6159 OpBuilder.addExclaimOverload(); 6160 break; 6161 6162 case OO_AmpAmp: 6163 case OO_PipePipe: 6164 OpBuilder.addAmpAmpOrPipePipeOverload(); 6165 break; 6166 6167 case OO_Subscript: 6168 OpBuilder.addSubscriptOverloads(); 6169 break; 6170 6171 case OO_ArrowStar: 6172 OpBuilder.addArrowStarOverloads(); 6173 break; 6174 6175 case OO_Conditional: 6176 OpBuilder.addConditionalOperatorOverloads(); 6177 OpBuilder.addGenericBinaryArithmeticOverloads(/*isComparison=*/false); 6178 break; 6179 } 6180} 6181 6182/// \brief Add function candidates found via argument-dependent lookup 6183/// to the set of overloading candidates. 6184/// 6185/// This routine performs argument-dependent name lookup based on the 6186/// given function name (which may also be an operator name) and adds 6187/// all of the overload candidates found by ADL to the overload 6188/// candidate set (C++ [basic.lookup.argdep]). 6189void 6190Sema::AddArgumentDependentLookupCandidates(DeclarationName Name, 6191 bool Operator, 6192 Expr **Args, unsigned NumArgs, 6193 TemplateArgumentListInfo *ExplicitTemplateArgs, 6194 OverloadCandidateSet& CandidateSet, 6195 bool PartialOverloading, 6196 bool StdNamespaceIsAssociated) { 6197 ADLResult Fns; 6198 6199 // FIXME: This approach for uniquing ADL results (and removing 6200 // redundant candidates from the set) relies on pointer-equality, 6201 // which means we need to key off the canonical decl. However, 6202 // always going back to the canonical decl might not get us the 6203 // right set of default arguments. What default arguments are 6204 // we supposed to consider on ADL candidates, anyway? 6205 6206 // FIXME: Pass in the explicit template arguments? 6207 ArgumentDependentLookup(Name, Operator, Args, NumArgs, Fns, 6208 StdNamespaceIsAssociated); 6209 6210 // Erase all of the candidates we already knew about. 6211 for (OverloadCandidateSet::iterator Cand = CandidateSet.begin(), 6212 CandEnd = CandidateSet.end(); 6213 Cand != CandEnd; ++Cand) 6214 if (Cand->Function) { 6215 Fns.erase(Cand->Function); 6216 if (FunctionTemplateDecl *FunTmpl = Cand->Function->getPrimaryTemplate()) 6217 Fns.erase(FunTmpl); 6218 } 6219 6220 // For each of the ADL candidates we found, add it to the overload 6221 // set. 6222 for (ADLResult::iterator I = Fns.begin(), E = Fns.end(); I != E; ++I) { 6223 DeclAccessPair FoundDecl = DeclAccessPair::make(*I, AS_none); 6224 if (FunctionDecl *FD = dyn_cast<FunctionDecl>(*I)) { 6225 if (ExplicitTemplateArgs) 6226 continue; 6227 6228 AddOverloadCandidate(FD, FoundDecl, Args, NumArgs, CandidateSet, 6229 false, PartialOverloading); 6230 } else 6231 AddTemplateOverloadCandidate(cast<FunctionTemplateDecl>(*I), 6232 FoundDecl, ExplicitTemplateArgs, 6233 Args, NumArgs, CandidateSet); 6234 } 6235} 6236 6237/// isBetterOverloadCandidate - Determines whether the first overload 6238/// candidate is a better candidate than the second (C++ 13.3.3p1). 6239bool 6240isBetterOverloadCandidate(Sema &S, 6241 const OverloadCandidate &Cand1, 6242 const OverloadCandidate &Cand2, 6243 SourceLocation Loc, 6244 bool UserDefinedConversion) { 6245 // Define viable functions to be better candidates than non-viable 6246 // functions. 6247 if (!Cand2.Viable) 6248 return Cand1.Viable; 6249 else if (!Cand1.Viable) 6250 return false; 6251 6252 // C++ [over.match.best]p1: 6253 // 6254 // -- if F is a static member function, ICS1(F) is defined such 6255 // that ICS1(F) is neither better nor worse than ICS1(G) for 6256 // any function G, and, symmetrically, ICS1(G) is neither 6257 // better nor worse than ICS1(F). 6258 unsigned StartArg = 0; 6259 if (Cand1.IgnoreObjectArgument || Cand2.IgnoreObjectArgument) 6260 StartArg = 1; 6261 6262 // C++ [over.match.best]p1: 6263 // A viable function F1 is defined to be a better function than another 6264 // viable function F2 if for all arguments i, ICSi(F1) is not a worse 6265 // conversion sequence than ICSi(F2), and then... 6266 unsigned NumArgs = Cand1.Conversions.size(); 6267 assert(Cand2.Conversions.size() == NumArgs && "Overload candidate mismatch"); 6268 bool HasBetterConversion = false; 6269 for (unsigned ArgIdx = StartArg; ArgIdx < NumArgs; ++ArgIdx) { 6270 switch (CompareImplicitConversionSequences(S, 6271 Cand1.Conversions[ArgIdx], 6272 Cand2.Conversions[ArgIdx])) { 6273 case ImplicitConversionSequence::Better: 6274 // Cand1 has a better conversion sequence. 6275 HasBetterConversion = true; 6276 break; 6277 6278 case ImplicitConversionSequence::Worse: 6279 // Cand1 can't be better than Cand2. 6280 return false; 6281 6282 case ImplicitConversionSequence::Indistinguishable: 6283 // Do nothing. 6284 break; 6285 } 6286 } 6287 6288 // -- for some argument j, ICSj(F1) is a better conversion sequence than 6289 // ICSj(F2), or, if not that, 6290 if (HasBetterConversion) 6291 return true; 6292 6293 // - F1 is a non-template function and F2 is a function template 6294 // specialization, or, if not that, 6295 if ((!Cand1.Function || !Cand1.Function->getPrimaryTemplate()) && 6296 Cand2.Function && Cand2.Function->getPrimaryTemplate()) 6297 return true; 6298 6299 // -- F1 and F2 are function template specializations, and the function 6300 // template for F1 is more specialized than the template for F2 6301 // according to the partial ordering rules described in 14.5.5.2, or, 6302 // if not that, 6303 if (Cand1.Function && Cand1.Function->getPrimaryTemplate() && 6304 Cand2.Function && Cand2.Function->getPrimaryTemplate()) { 6305 if (FunctionTemplateDecl *BetterTemplate 6306 = S.getMoreSpecializedTemplate(Cand1.Function->getPrimaryTemplate(), 6307 Cand2.Function->getPrimaryTemplate(), 6308 Loc, 6309 isa<CXXConversionDecl>(Cand1.Function)? TPOC_Conversion 6310 : TPOC_Call, 6311 Cand1.ExplicitCallArguments)) 6312 return BetterTemplate == Cand1.Function->getPrimaryTemplate(); 6313 } 6314 6315 // -- the context is an initialization by user-defined conversion 6316 // (see 8.5, 13.3.1.5) and the standard conversion sequence 6317 // from the return type of F1 to the destination type (i.e., 6318 // the type of the entity being initialized) is a better 6319 // conversion sequence than the standard conversion sequence 6320 // from the return type of F2 to the destination type. 6321 if (UserDefinedConversion && Cand1.Function && Cand2.Function && 6322 isa<CXXConversionDecl>(Cand1.Function) && 6323 isa<CXXConversionDecl>(Cand2.Function)) { 6324 switch (CompareStandardConversionSequences(S, 6325 Cand1.FinalConversion, 6326 Cand2.FinalConversion)) { 6327 case ImplicitConversionSequence::Better: 6328 // Cand1 has a better conversion sequence. 6329 return true; 6330 6331 case ImplicitConversionSequence::Worse: 6332 // Cand1 can't be better than Cand2. 6333 return false; 6334 6335 case ImplicitConversionSequence::Indistinguishable: 6336 // Do nothing 6337 break; 6338 } 6339 } 6340 6341 return false; 6342} 6343 6344/// \brief Computes the best viable function (C++ 13.3.3) 6345/// within an overload candidate set. 6346/// 6347/// \param CandidateSet the set of candidate functions. 6348/// 6349/// \param Loc the location of the function name (or operator symbol) for 6350/// which overload resolution occurs. 6351/// 6352/// \param Best f overload resolution was successful or found a deleted 6353/// function, Best points to the candidate function found. 6354/// 6355/// \returns The result of overload resolution. 6356OverloadingResult 6357OverloadCandidateSet::BestViableFunction(Sema &S, SourceLocation Loc, 6358 iterator &Best, 6359 bool UserDefinedConversion) { 6360 // Find the best viable function. 6361 Best = end(); 6362 for (iterator Cand = begin(); Cand != end(); ++Cand) { 6363 if (Cand->Viable) 6364 if (Best == end() || isBetterOverloadCandidate(S, *Cand, *Best, Loc, 6365 UserDefinedConversion)) 6366 Best = Cand; 6367 } 6368 6369 // If we didn't find any viable functions, abort. 6370 if (Best == end()) 6371 return OR_No_Viable_Function; 6372 6373 // Make sure that this function is better than every other viable 6374 // function. If not, we have an ambiguity. 6375 for (iterator Cand = begin(); Cand != end(); ++Cand) { 6376 if (Cand->Viable && 6377 Cand != Best && 6378 !isBetterOverloadCandidate(S, *Best, *Cand, Loc, 6379 UserDefinedConversion)) { 6380 Best = end(); 6381 return OR_Ambiguous; 6382 } 6383 } 6384 6385 // Best is the best viable function. 6386 if (Best->Function && 6387 (Best->Function->isDeleted() || Best->Function->isUnavailable())) 6388 return OR_Deleted; 6389 6390 return OR_Success; 6391} 6392 6393namespace { 6394 6395enum OverloadCandidateKind { 6396 oc_function, 6397 oc_method, 6398 oc_constructor, 6399 oc_function_template, 6400 oc_method_template, 6401 oc_constructor_template, 6402 oc_implicit_default_constructor, 6403 oc_implicit_copy_constructor, 6404 oc_implicit_copy_assignment, 6405 oc_implicit_inherited_constructor 6406}; 6407 6408OverloadCandidateKind ClassifyOverloadCandidate(Sema &S, 6409 FunctionDecl *Fn, 6410 std::string &Description) { 6411 bool isTemplate = false; 6412 6413 if (FunctionTemplateDecl *FunTmpl = Fn->getPrimaryTemplate()) { 6414 isTemplate = true; 6415 Description = S.getTemplateArgumentBindingsText( 6416 FunTmpl->getTemplateParameters(), *Fn->getTemplateSpecializationArgs()); 6417 } 6418 6419 if (CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn)) { 6420 if (!Ctor->isImplicit()) 6421 return isTemplate ? oc_constructor_template : oc_constructor; 6422 6423 if (Ctor->getInheritedConstructor()) 6424 return oc_implicit_inherited_constructor; 6425 6426 return Ctor->isCopyConstructor() ? oc_implicit_copy_constructor 6427 : oc_implicit_default_constructor; 6428 } 6429 6430 if (CXXMethodDecl *Meth = dyn_cast<CXXMethodDecl>(Fn)) { 6431 // This actually gets spelled 'candidate function' for now, but 6432 // it doesn't hurt to split it out. 6433 if (!Meth->isImplicit()) 6434 return isTemplate ? oc_method_template : oc_method; 6435 6436 assert(Meth->isCopyAssignmentOperator() 6437 && "implicit method is not copy assignment operator?"); 6438 return oc_implicit_copy_assignment; 6439 } 6440 6441 return isTemplate ? oc_function_template : oc_function; 6442} 6443 6444void MaybeEmitInheritedConstructorNote(Sema &S, FunctionDecl *Fn) { 6445 const CXXConstructorDecl *Ctor = dyn_cast<CXXConstructorDecl>(Fn); 6446 if (!Ctor) return; 6447 6448 Ctor = Ctor->getInheritedConstructor(); 6449 if (!Ctor) return; 6450 6451 S.Diag(Ctor->getLocation(), diag::note_ovl_candidate_inherited_constructor); 6452} 6453 6454} // end anonymous namespace 6455 6456// Notes the location of an overload candidate. 6457void Sema::NoteOverloadCandidate(FunctionDecl *Fn) { 6458 std::string FnDesc; 6459 OverloadCandidateKind K = ClassifyOverloadCandidate(*this, Fn, FnDesc); 6460 Diag(Fn->getLocation(), diag::note_ovl_candidate) 6461 << (unsigned) K << FnDesc; 6462 MaybeEmitInheritedConstructorNote(*this, Fn); 6463} 6464 6465//Notes the location of all overload candidates designated through 6466// OverloadedExpr 6467void Sema::NoteAllOverloadCandidates(Expr* OverloadedExpr) { 6468 assert(OverloadedExpr->getType() == Context.OverloadTy); 6469 6470 OverloadExpr::FindResult Ovl = OverloadExpr::find(OverloadedExpr); 6471 OverloadExpr *OvlExpr = Ovl.Expression; 6472 6473 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 6474 IEnd = OvlExpr->decls_end(); 6475 I != IEnd; ++I) { 6476 if (FunctionTemplateDecl *FunTmpl = 6477 dyn_cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()) ) { 6478 NoteOverloadCandidate(FunTmpl->getTemplatedDecl()); 6479 } else if (FunctionDecl *Fun 6480 = dyn_cast<FunctionDecl>((*I)->getUnderlyingDecl()) ) { 6481 NoteOverloadCandidate(Fun); 6482 } 6483 } 6484} 6485 6486/// Diagnoses an ambiguous conversion. The partial diagnostic is the 6487/// "lead" diagnostic; it will be given two arguments, the source and 6488/// target types of the conversion. 6489void ImplicitConversionSequence::DiagnoseAmbiguousConversion( 6490 Sema &S, 6491 SourceLocation CaretLoc, 6492 const PartialDiagnostic &PDiag) const { 6493 S.Diag(CaretLoc, PDiag) 6494 << Ambiguous.getFromType() << Ambiguous.getToType(); 6495 for (AmbiguousConversionSequence::const_iterator 6496 I = Ambiguous.begin(), E = Ambiguous.end(); I != E; ++I) { 6497 S.NoteOverloadCandidate(*I); 6498 } 6499} 6500 6501namespace { 6502 6503void DiagnoseBadConversion(Sema &S, OverloadCandidate *Cand, unsigned I) { 6504 const ImplicitConversionSequence &Conv = Cand->Conversions[I]; 6505 assert(Conv.isBad()); 6506 assert(Cand->Function && "for now, candidate must be a function"); 6507 FunctionDecl *Fn = Cand->Function; 6508 6509 // There's a conversion slot for the object argument if this is a 6510 // non-constructor method. Note that 'I' corresponds the 6511 // conversion-slot index. 6512 bool isObjectArgument = false; 6513 if (isa<CXXMethodDecl>(Fn) && !isa<CXXConstructorDecl>(Fn)) { 6514 if (I == 0) 6515 isObjectArgument = true; 6516 else 6517 I--; 6518 } 6519 6520 std::string FnDesc; 6521 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 6522 6523 Expr *FromExpr = Conv.Bad.FromExpr; 6524 QualType FromTy = Conv.Bad.getFromType(); 6525 QualType ToTy = Conv.Bad.getToType(); 6526 6527 if (FromTy == S.Context.OverloadTy) { 6528 assert(FromExpr && "overload set argument came from implicit argument?"); 6529 Expr *E = FromExpr->IgnoreParens(); 6530 if (isa<UnaryOperator>(E)) 6531 E = cast<UnaryOperator>(E)->getSubExpr()->IgnoreParens(); 6532 DeclarationName Name = cast<OverloadExpr>(E)->getName(); 6533 6534 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_overload) 6535 << (unsigned) FnKind << FnDesc 6536 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6537 << ToTy << Name << I+1; 6538 MaybeEmitInheritedConstructorNote(S, Fn); 6539 return; 6540 } 6541 6542 // Do some hand-waving analysis to see if the non-viability is due 6543 // to a qualifier mismatch. 6544 CanQualType CFromTy = S.Context.getCanonicalType(FromTy); 6545 CanQualType CToTy = S.Context.getCanonicalType(ToTy); 6546 if (CanQual<ReferenceType> RT = CToTy->getAs<ReferenceType>()) 6547 CToTy = RT->getPointeeType(); 6548 else { 6549 // TODO: detect and diagnose the full richness of const mismatches. 6550 if (CanQual<PointerType> FromPT = CFromTy->getAs<PointerType>()) 6551 if (CanQual<PointerType> ToPT = CToTy->getAs<PointerType>()) 6552 CFromTy = FromPT->getPointeeType(), CToTy = ToPT->getPointeeType(); 6553 } 6554 6555 if (CToTy.getUnqualifiedType() == CFromTy.getUnqualifiedType() && 6556 !CToTy.isAtLeastAsQualifiedAs(CFromTy)) { 6557 // It is dumb that we have to do this here. 6558 while (isa<ArrayType>(CFromTy)) 6559 CFromTy = CFromTy->getAs<ArrayType>()->getElementType(); 6560 while (isa<ArrayType>(CToTy)) 6561 CToTy = CFromTy->getAs<ArrayType>()->getElementType(); 6562 6563 Qualifiers FromQs = CFromTy.getQualifiers(); 6564 Qualifiers ToQs = CToTy.getQualifiers(); 6565 6566 if (FromQs.getAddressSpace() != ToQs.getAddressSpace()) { 6567 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_addrspace) 6568 << (unsigned) FnKind << FnDesc 6569 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6570 << FromTy 6571 << FromQs.getAddressSpace() << ToQs.getAddressSpace() 6572 << (unsigned) isObjectArgument << I+1; 6573 MaybeEmitInheritedConstructorNote(S, Fn); 6574 return; 6575 } 6576 6577 if (FromQs.getObjCGCAttr() != ToQs.getObjCGCAttr()) { 6578 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_gc) 6579 << (unsigned) FnKind << FnDesc 6580 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6581 << FromTy 6582 << FromQs.getObjCGCAttr() << ToQs.getObjCGCAttr() 6583 << (unsigned) isObjectArgument << I+1; 6584 MaybeEmitInheritedConstructorNote(S, Fn); 6585 return; 6586 } 6587 6588 unsigned CVR = FromQs.getCVRQualifiers() & ~ToQs.getCVRQualifiers(); 6589 assert(CVR && "unexpected qualifiers mismatch"); 6590 6591 if (isObjectArgument) { 6592 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr_this) 6593 << (unsigned) FnKind << FnDesc 6594 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6595 << FromTy << (CVR - 1); 6596 } else { 6597 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_cvr) 6598 << (unsigned) FnKind << FnDesc 6599 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6600 << FromTy << (CVR - 1) << I+1; 6601 } 6602 MaybeEmitInheritedConstructorNote(S, Fn); 6603 return; 6604 } 6605 6606 // Diagnose references or pointers to incomplete types differently, 6607 // since it's far from impossible that the incompleteness triggered 6608 // the failure. 6609 QualType TempFromTy = FromTy.getNonReferenceType(); 6610 if (const PointerType *PTy = TempFromTy->getAs<PointerType>()) 6611 TempFromTy = PTy->getPointeeType(); 6612 if (TempFromTy->isIncompleteType()) { 6613 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv_incomplete) 6614 << (unsigned) FnKind << FnDesc 6615 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6616 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 6617 MaybeEmitInheritedConstructorNote(S, Fn); 6618 return; 6619 } 6620 6621 // Diagnose base -> derived pointer conversions. 6622 unsigned BaseToDerivedConversion = 0; 6623 if (const PointerType *FromPtrTy = FromTy->getAs<PointerType>()) { 6624 if (const PointerType *ToPtrTy = ToTy->getAs<PointerType>()) { 6625 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 6626 FromPtrTy->getPointeeType()) && 6627 !FromPtrTy->getPointeeType()->isIncompleteType() && 6628 !ToPtrTy->getPointeeType()->isIncompleteType() && 6629 S.IsDerivedFrom(ToPtrTy->getPointeeType(), 6630 FromPtrTy->getPointeeType())) 6631 BaseToDerivedConversion = 1; 6632 } 6633 } else if (const ObjCObjectPointerType *FromPtrTy 6634 = FromTy->getAs<ObjCObjectPointerType>()) { 6635 if (const ObjCObjectPointerType *ToPtrTy 6636 = ToTy->getAs<ObjCObjectPointerType>()) 6637 if (const ObjCInterfaceDecl *FromIface = FromPtrTy->getInterfaceDecl()) 6638 if (const ObjCInterfaceDecl *ToIface = ToPtrTy->getInterfaceDecl()) 6639 if (ToPtrTy->getPointeeType().isAtLeastAsQualifiedAs( 6640 FromPtrTy->getPointeeType()) && 6641 FromIface->isSuperClassOf(ToIface)) 6642 BaseToDerivedConversion = 2; 6643 } else if (const ReferenceType *ToRefTy = ToTy->getAs<ReferenceType>()) { 6644 if (ToRefTy->getPointeeType().isAtLeastAsQualifiedAs(FromTy) && 6645 !FromTy->isIncompleteType() && 6646 !ToRefTy->getPointeeType()->isIncompleteType() && 6647 S.IsDerivedFrom(ToRefTy->getPointeeType(), FromTy)) 6648 BaseToDerivedConversion = 3; 6649 } 6650 6651 if (BaseToDerivedConversion) { 6652 S.Diag(Fn->getLocation(), 6653 diag::note_ovl_candidate_bad_base_to_derived_conv) 6654 << (unsigned) FnKind << FnDesc 6655 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6656 << (BaseToDerivedConversion - 1) 6657 << FromTy << ToTy << I+1; 6658 MaybeEmitInheritedConstructorNote(S, Fn); 6659 return; 6660 } 6661 6662 // TODO: specialize more based on the kind of mismatch 6663 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_conv) 6664 << (unsigned) FnKind << FnDesc 6665 << (FromExpr ? FromExpr->getSourceRange() : SourceRange()) 6666 << FromTy << ToTy << (unsigned) isObjectArgument << I+1; 6667 MaybeEmitInheritedConstructorNote(S, Fn); 6668} 6669 6670void DiagnoseArityMismatch(Sema &S, OverloadCandidate *Cand, 6671 unsigned NumFormalArgs) { 6672 // TODO: treat calls to a missing default constructor as a special case 6673 6674 FunctionDecl *Fn = Cand->Function; 6675 const FunctionProtoType *FnTy = Fn->getType()->getAs<FunctionProtoType>(); 6676 6677 unsigned MinParams = Fn->getMinRequiredArguments(); 6678 6679 // at least / at most / exactly 6680 unsigned mode, modeCount; 6681 if (NumFormalArgs < MinParams) { 6682 assert((Cand->FailureKind == ovl_fail_too_few_arguments) || 6683 (Cand->FailureKind == ovl_fail_bad_deduction && 6684 Cand->DeductionFailure.Result == Sema::TDK_TooFewArguments)); 6685 if (MinParams != FnTy->getNumArgs() || 6686 FnTy->isVariadic() || FnTy->isTemplateVariadic()) 6687 mode = 0; // "at least" 6688 else 6689 mode = 2; // "exactly" 6690 modeCount = MinParams; 6691 } else { 6692 assert((Cand->FailureKind == ovl_fail_too_many_arguments) || 6693 (Cand->FailureKind == ovl_fail_bad_deduction && 6694 Cand->DeductionFailure.Result == Sema::TDK_TooManyArguments)); 6695 if (MinParams != FnTy->getNumArgs()) 6696 mode = 1; // "at most" 6697 else 6698 mode = 2; // "exactly" 6699 modeCount = FnTy->getNumArgs(); 6700 } 6701 6702 std::string Description; 6703 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, Description); 6704 6705 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_arity) 6706 << (unsigned) FnKind << (Fn->getDescribedFunctionTemplate() != 0) << mode 6707 << modeCount << NumFormalArgs; 6708 MaybeEmitInheritedConstructorNote(S, Fn); 6709} 6710 6711/// Diagnose a failed template-argument deduction. 6712void DiagnoseBadDeduction(Sema &S, OverloadCandidate *Cand, 6713 Expr **Args, unsigned NumArgs) { 6714 FunctionDecl *Fn = Cand->Function; // pattern 6715 6716 TemplateParameter Param = Cand->DeductionFailure.getTemplateParameter(); 6717 NamedDecl *ParamD; 6718 (ParamD = Param.dyn_cast<TemplateTypeParmDecl*>()) || 6719 (ParamD = Param.dyn_cast<NonTypeTemplateParmDecl*>()) || 6720 (ParamD = Param.dyn_cast<TemplateTemplateParmDecl*>()); 6721 switch (Cand->DeductionFailure.Result) { 6722 case Sema::TDK_Success: 6723 llvm_unreachable("TDK_success while diagnosing bad deduction"); 6724 6725 case Sema::TDK_Incomplete: { 6726 assert(ParamD && "no parameter found for incomplete deduction result"); 6727 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_incomplete_deduction) 6728 << ParamD->getDeclName(); 6729 MaybeEmitInheritedConstructorNote(S, Fn); 6730 return; 6731 } 6732 6733 case Sema::TDK_Underqualified: { 6734 assert(ParamD && "no parameter found for bad qualifiers deduction result"); 6735 TemplateTypeParmDecl *TParam = cast<TemplateTypeParmDecl>(ParamD); 6736 6737 QualType Param = Cand->DeductionFailure.getFirstArg()->getAsType(); 6738 6739 // Param will have been canonicalized, but it should just be a 6740 // qualified version of ParamD, so move the qualifiers to that. 6741 QualifierCollector Qs; 6742 Qs.strip(Param); 6743 QualType NonCanonParam = Qs.apply(S.Context, TParam->getTypeForDecl()); 6744 assert(S.Context.hasSameType(Param, NonCanonParam)); 6745 6746 // Arg has also been canonicalized, but there's nothing we can do 6747 // about that. It also doesn't matter as much, because it won't 6748 // have any template parameters in it (because deduction isn't 6749 // done on dependent types). 6750 QualType Arg = Cand->DeductionFailure.getSecondArg()->getAsType(); 6751 6752 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_underqualified) 6753 << ParamD->getDeclName() << Arg << NonCanonParam; 6754 MaybeEmitInheritedConstructorNote(S, Fn); 6755 return; 6756 } 6757 6758 case Sema::TDK_Inconsistent: { 6759 assert(ParamD && "no parameter found for inconsistent deduction result"); 6760 int which = 0; 6761 if (isa<TemplateTypeParmDecl>(ParamD)) 6762 which = 0; 6763 else if (isa<NonTypeTemplateParmDecl>(ParamD)) 6764 which = 1; 6765 else { 6766 which = 2; 6767 } 6768 6769 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_inconsistent_deduction) 6770 << which << ParamD->getDeclName() 6771 << *Cand->DeductionFailure.getFirstArg() 6772 << *Cand->DeductionFailure.getSecondArg(); 6773 MaybeEmitInheritedConstructorNote(S, Fn); 6774 return; 6775 } 6776 6777 case Sema::TDK_InvalidExplicitArguments: 6778 assert(ParamD && "no parameter found for invalid explicit arguments"); 6779 if (ParamD->getDeclName()) 6780 S.Diag(Fn->getLocation(), 6781 diag::note_ovl_candidate_explicit_arg_mismatch_named) 6782 << ParamD->getDeclName(); 6783 else { 6784 int index = 0; 6785 if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(ParamD)) 6786 index = TTP->getIndex(); 6787 else if (NonTypeTemplateParmDecl *NTTP 6788 = dyn_cast<NonTypeTemplateParmDecl>(ParamD)) 6789 index = NTTP->getIndex(); 6790 else 6791 index = cast<TemplateTemplateParmDecl>(ParamD)->getIndex(); 6792 S.Diag(Fn->getLocation(), 6793 diag::note_ovl_candidate_explicit_arg_mismatch_unnamed) 6794 << (index + 1); 6795 } 6796 MaybeEmitInheritedConstructorNote(S, Fn); 6797 return; 6798 6799 case Sema::TDK_TooManyArguments: 6800 case Sema::TDK_TooFewArguments: 6801 DiagnoseArityMismatch(S, Cand, NumArgs); 6802 return; 6803 6804 case Sema::TDK_InstantiationDepth: 6805 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_instantiation_depth); 6806 MaybeEmitInheritedConstructorNote(S, Fn); 6807 return; 6808 6809 case Sema::TDK_SubstitutionFailure: { 6810 std::string ArgString; 6811 if (TemplateArgumentList *Args 6812 = Cand->DeductionFailure.getTemplateArgumentList()) 6813 ArgString = S.getTemplateArgumentBindingsText( 6814 Fn->getDescribedFunctionTemplate()->getTemplateParameters(), 6815 *Args); 6816 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_substitution_failure) 6817 << ArgString; 6818 MaybeEmitInheritedConstructorNote(S, Fn); 6819 return; 6820 } 6821 6822 // TODO: diagnose these individually, then kill off 6823 // note_ovl_candidate_bad_deduction, which is uselessly vague. 6824 case Sema::TDK_NonDeducedMismatch: 6825 case Sema::TDK_FailedOverloadResolution: 6826 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_bad_deduction); 6827 MaybeEmitInheritedConstructorNote(S, Fn); 6828 return; 6829 } 6830} 6831 6832/// Generates a 'note' diagnostic for an overload candidate. We've 6833/// already generated a primary error at the call site. 6834/// 6835/// It really does need to be a single diagnostic with its caret 6836/// pointed at the candidate declaration. Yes, this creates some 6837/// major challenges of technical writing. Yes, this makes pointing 6838/// out problems with specific arguments quite awkward. It's still 6839/// better than generating twenty screens of text for every failed 6840/// overload. 6841/// 6842/// It would be great to be able to express per-candidate problems 6843/// more richly for those diagnostic clients that cared, but we'd 6844/// still have to be just as careful with the default diagnostics. 6845void NoteFunctionCandidate(Sema &S, OverloadCandidate *Cand, 6846 Expr **Args, unsigned NumArgs) { 6847 FunctionDecl *Fn = Cand->Function; 6848 6849 // Note deleted candidates, but only if they're viable. 6850 if (Cand->Viable && (Fn->isDeleted() || Fn->isUnavailable())) { 6851 std::string FnDesc; 6852 OverloadCandidateKind FnKind = ClassifyOverloadCandidate(S, Fn, FnDesc); 6853 6854 S.Diag(Fn->getLocation(), diag::note_ovl_candidate_deleted) 6855 << FnKind << FnDesc << Fn->isDeleted(); 6856 MaybeEmitInheritedConstructorNote(S, Fn); 6857 return; 6858 } 6859 6860 // We don't really have anything else to say about viable candidates. 6861 if (Cand->Viable) { 6862 S.NoteOverloadCandidate(Fn); 6863 return; 6864 } 6865 6866 switch (Cand->FailureKind) { 6867 case ovl_fail_too_many_arguments: 6868 case ovl_fail_too_few_arguments: 6869 return DiagnoseArityMismatch(S, Cand, NumArgs); 6870 6871 case ovl_fail_bad_deduction: 6872 return DiagnoseBadDeduction(S, Cand, Args, NumArgs); 6873 6874 case ovl_fail_trivial_conversion: 6875 case ovl_fail_bad_final_conversion: 6876 case ovl_fail_final_conversion_not_exact: 6877 return S.NoteOverloadCandidate(Fn); 6878 6879 case ovl_fail_bad_conversion: { 6880 unsigned I = (Cand->IgnoreObjectArgument ? 1 : 0); 6881 for (unsigned N = Cand->Conversions.size(); I != N; ++I) 6882 if (Cand->Conversions[I].isBad()) 6883 return DiagnoseBadConversion(S, Cand, I); 6884 6885 // FIXME: this currently happens when we're called from SemaInit 6886 // when user-conversion overload fails. Figure out how to handle 6887 // those conditions and diagnose them well. 6888 return S.NoteOverloadCandidate(Fn); 6889 } 6890 } 6891} 6892 6893void NoteSurrogateCandidate(Sema &S, OverloadCandidate *Cand) { 6894 // Desugar the type of the surrogate down to a function type, 6895 // retaining as many typedefs as possible while still showing 6896 // the function type (and, therefore, its parameter types). 6897 QualType FnType = Cand->Surrogate->getConversionType(); 6898 bool isLValueReference = false; 6899 bool isRValueReference = false; 6900 bool isPointer = false; 6901 if (const LValueReferenceType *FnTypeRef = 6902 FnType->getAs<LValueReferenceType>()) { 6903 FnType = FnTypeRef->getPointeeType(); 6904 isLValueReference = true; 6905 } else if (const RValueReferenceType *FnTypeRef = 6906 FnType->getAs<RValueReferenceType>()) { 6907 FnType = FnTypeRef->getPointeeType(); 6908 isRValueReference = true; 6909 } 6910 if (const PointerType *FnTypePtr = FnType->getAs<PointerType>()) { 6911 FnType = FnTypePtr->getPointeeType(); 6912 isPointer = true; 6913 } 6914 // Desugar down to a function type. 6915 FnType = QualType(FnType->getAs<FunctionType>(), 0); 6916 // Reconstruct the pointer/reference as appropriate. 6917 if (isPointer) FnType = S.Context.getPointerType(FnType); 6918 if (isRValueReference) FnType = S.Context.getRValueReferenceType(FnType); 6919 if (isLValueReference) FnType = S.Context.getLValueReferenceType(FnType); 6920 6921 S.Diag(Cand->Surrogate->getLocation(), diag::note_ovl_surrogate_cand) 6922 << FnType; 6923 MaybeEmitInheritedConstructorNote(S, Cand->Surrogate); 6924} 6925 6926void NoteBuiltinOperatorCandidate(Sema &S, 6927 const char *Opc, 6928 SourceLocation OpLoc, 6929 OverloadCandidate *Cand) { 6930 assert(Cand->Conversions.size() <= 2 && "builtin operator is not binary"); 6931 std::string TypeStr("operator"); 6932 TypeStr += Opc; 6933 TypeStr += "("; 6934 TypeStr += Cand->BuiltinTypes.ParamTypes[0].getAsString(); 6935 if (Cand->Conversions.size() == 1) { 6936 TypeStr += ")"; 6937 S.Diag(OpLoc, diag::note_ovl_builtin_unary_candidate) << TypeStr; 6938 } else { 6939 TypeStr += ", "; 6940 TypeStr += Cand->BuiltinTypes.ParamTypes[1].getAsString(); 6941 TypeStr += ")"; 6942 S.Diag(OpLoc, diag::note_ovl_builtin_binary_candidate) << TypeStr; 6943 } 6944} 6945 6946void NoteAmbiguousUserConversions(Sema &S, SourceLocation OpLoc, 6947 OverloadCandidate *Cand) { 6948 unsigned NoOperands = Cand->Conversions.size(); 6949 for (unsigned ArgIdx = 0; ArgIdx < NoOperands; ++ArgIdx) { 6950 const ImplicitConversionSequence &ICS = Cand->Conversions[ArgIdx]; 6951 if (ICS.isBad()) break; // all meaningless after first invalid 6952 if (!ICS.isAmbiguous()) continue; 6953 6954 ICS.DiagnoseAmbiguousConversion(S, OpLoc, 6955 S.PDiag(diag::note_ambiguous_type_conversion)); 6956 } 6957} 6958 6959SourceLocation GetLocationForCandidate(const OverloadCandidate *Cand) { 6960 if (Cand->Function) 6961 return Cand->Function->getLocation(); 6962 if (Cand->IsSurrogate) 6963 return Cand->Surrogate->getLocation(); 6964 return SourceLocation(); 6965} 6966 6967struct CompareOverloadCandidatesForDisplay { 6968 Sema &S; 6969 CompareOverloadCandidatesForDisplay(Sema &S) : S(S) {} 6970 6971 bool operator()(const OverloadCandidate *L, 6972 const OverloadCandidate *R) { 6973 // Fast-path this check. 6974 if (L == R) return false; 6975 6976 // Order first by viability. 6977 if (L->Viable) { 6978 if (!R->Viable) return true; 6979 6980 // TODO: introduce a tri-valued comparison for overload 6981 // candidates. Would be more worthwhile if we had a sort 6982 // that could exploit it. 6983 if (isBetterOverloadCandidate(S, *L, *R, SourceLocation())) return true; 6984 if (isBetterOverloadCandidate(S, *R, *L, SourceLocation())) return false; 6985 } else if (R->Viable) 6986 return false; 6987 6988 assert(L->Viable == R->Viable); 6989 6990 // Criteria by which we can sort non-viable candidates: 6991 if (!L->Viable) { 6992 // 1. Arity mismatches come after other candidates. 6993 if (L->FailureKind == ovl_fail_too_many_arguments || 6994 L->FailureKind == ovl_fail_too_few_arguments) 6995 return false; 6996 if (R->FailureKind == ovl_fail_too_many_arguments || 6997 R->FailureKind == ovl_fail_too_few_arguments) 6998 return true; 6999 7000 // 2. Bad conversions come first and are ordered by the number 7001 // of bad conversions and quality of good conversions. 7002 if (L->FailureKind == ovl_fail_bad_conversion) { 7003 if (R->FailureKind != ovl_fail_bad_conversion) 7004 return true; 7005 7006 // If there's any ordering between the defined conversions... 7007 // FIXME: this might not be transitive. 7008 assert(L->Conversions.size() == R->Conversions.size()); 7009 7010 int leftBetter = 0; 7011 unsigned I = (L->IgnoreObjectArgument || R->IgnoreObjectArgument); 7012 for (unsigned E = L->Conversions.size(); I != E; ++I) { 7013 switch (CompareImplicitConversionSequences(S, 7014 L->Conversions[I], 7015 R->Conversions[I])) { 7016 case ImplicitConversionSequence::Better: 7017 leftBetter++; 7018 break; 7019 7020 case ImplicitConversionSequence::Worse: 7021 leftBetter--; 7022 break; 7023 7024 case ImplicitConversionSequence::Indistinguishable: 7025 break; 7026 } 7027 } 7028 if (leftBetter > 0) return true; 7029 if (leftBetter < 0) return false; 7030 7031 } else if (R->FailureKind == ovl_fail_bad_conversion) 7032 return false; 7033 7034 // TODO: others? 7035 } 7036 7037 // Sort everything else by location. 7038 SourceLocation LLoc = GetLocationForCandidate(L); 7039 SourceLocation RLoc = GetLocationForCandidate(R); 7040 7041 // Put candidates without locations (e.g. builtins) at the end. 7042 if (LLoc.isInvalid()) return false; 7043 if (RLoc.isInvalid()) return true; 7044 7045 return S.SourceMgr.isBeforeInTranslationUnit(LLoc, RLoc); 7046 } 7047}; 7048 7049/// CompleteNonViableCandidate - Normally, overload resolution only 7050/// computes up to the first 7051void CompleteNonViableCandidate(Sema &S, OverloadCandidate *Cand, 7052 Expr **Args, unsigned NumArgs) { 7053 assert(!Cand->Viable); 7054 7055 // Don't do anything on failures other than bad conversion. 7056 if (Cand->FailureKind != ovl_fail_bad_conversion) return; 7057 7058 // Skip forward to the first bad conversion. 7059 unsigned ConvIdx = (Cand->IgnoreObjectArgument ? 1 : 0); 7060 unsigned ConvCount = Cand->Conversions.size(); 7061 while (true) { 7062 assert(ConvIdx != ConvCount && "no bad conversion in candidate"); 7063 ConvIdx++; 7064 if (Cand->Conversions[ConvIdx - 1].isBad()) 7065 break; 7066 } 7067 7068 if (ConvIdx == ConvCount) 7069 return; 7070 7071 assert(!Cand->Conversions[ConvIdx].isInitialized() && 7072 "remaining conversion is initialized?"); 7073 7074 // FIXME: this should probably be preserved from the overload 7075 // operation somehow. 7076 bool SuppressUserConversions = false; 7077 7078 const FunctionProtoType* Proto; 7079 unsigned ArgIdx = ConvIdx; 7080 7081 if (Cand->IsSurrogate) { 7082 QualType ConvType 7083 = Cand->Surrogate->getConversionType().getNonReferenceType(); 7084 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 7085 ConvType = ConvPtrType->getPointeeType(); 7086 Proto = ConvType->getAs<FunctionProtoType>(); 7087 ArgIdx--; 7088 } else if (Cand->Function) { 7089 Proto = Cand->Function->getType()->getAs<FunctionProtoType>(); 7090 if (isa<CXXMethodDecl>(Cand->Function) && 7091 !isa<CXXConstructorDecl>(Cand->Function)) 7092 ArgIdx--; 7093 } else { 7094 // Builtin binary operator with a bad first conversion. 7095 assert(ConvCount <= 3); 7096 for (; ConvIdx != ConvCount; ++ConvIdx) 7097 Cand->Conversions[ConvIdx] 7098 = TryCopyInitialization(S, Args[ConvIdx], 7099 Cand->BuiltinTypes.ParamTypes[ConvIdx], 7100 SuppressUserConversions, 7101 /*InOverloadResolution*/ true); 7102 return; 7103 } 7104 7105 // Fill in the rest of the conversions. 7106 unsigned NumArgsInProto = Proto->getNumArgs(); 7107 for (; ConvIdx != ConvCount; ++ConvIdx, ++ArgIdx) { 7108 if (ArgIdx < NumArgsInProto) 7109 Cand->Conversions[ConvIdx] 7110 = TryCopyInitialization(S, Args[ArgIdx], Proto->getArgType(ArgIdx), 7111 SuppressUserConversions, 7112 /*InOverloadResolution=*/true); 7113 else 7114 Cand->Conversions[ConvIdx].setEllipsis(); 7115 } 7116} 7117 7118} // end anonymous namespace 7119 7120/// PrintOverloadCandidates - When overload resolution fails, prints 7121/// diagnostic messages containing the candidates in the candidate 7122/// set. 7123void OverloadCandidateSet::NoteCandidates(Sema &S, 7124 OverloadCandidateDisplayKind OCD, 7125 Expr **Args, unsigned NumArgs, 7126 const char *Opc, 7127 SourceLocation OpLoc) { 7128 // Sort the candidates by viability and position. Sorting directly would 7129 // be prohibitive, so we make a set of pointers and sort those. 7130 llvm::SmallVector<OverloadCandidate*, 32> Cands; 7131 if (OCD == OCD_AllCandidates) Cands.reserve(size()); 7132 for (iterator Cand = begin(), LastCand = end(); Cand != LastCand; ++Cand) { 7133 if (Cand->Viable) 7134 Cands.push_back(Cand); 7135 else if (OCD == OCD_AllCandidates) { 7136 CompleteNonViableCandidate(S, Cand, Args, NumArgs); 7137 if (Cand->Function || Cand->IsSurrogate) 7138 Cands.push_back(Cand); 7139 // Otherwise, this a non-viable builtin candidate. We do not, in general, 7140 // want to list every possible builtin candidate. 7141 } 7142 } 7143 7144 std::sort(Cands.begin(), Cands.end(), 7145 CompareOverloadCandidatesForDisplay(S)); 7146 7147 bool ReportedAmbiguousConversions = false; 7148 7149 llvm::SmallVectorImpl<OverloadCandidate*>::iterator I, E; 7150 const Diagnostic::OverloadsShown ShowOverloads = S.Diags.getShowOverloads(); 7151 unsigned CandsShown = 0; 7152 for (I = Cands.begin(), E = Cands.end(); I != E; ++I) { 7153 OverloadCandidate *Cand = *I; 7154 7155 // Set an arbitrary limit on the number of candidate functions we'll spam 7156 // the user with. FIXME: This limit should depend on details of the 7157 // candidate list. 7158 if (CandsShown >= 4 && ShowOverloads == Diagnostic::Ovl_Best) { 7159 break; 7160 } 7161 ++CandsShown; 7162 7163 if (Cand->Function) 7164 NoteFunctionCandidate(S, Cand, Args, NumArgs); 7165 else if (Cand->IsSurrogate) 7166 NoteSurrogateCandidate(S, Cand); 7167 else { 7168 assert(Cand->Viable && 7169 "Non-viable built-in candidates are not added to Cands."); 7170 // Generally we only see ambiguities including viable builtin 7171 // operators if overload resolution got screwed up by an 7172 // ambiguous user-defined conversion. 7173 // 7174 // FIXME: It's quite possible for different conversions to see 7175 // different ambiguities, though. 7176 if (!ReportedAmbiguousConversions) { 7177 NoteAmbiguousUserConversions(S, OpLoc, Cand); 7178 ReportedAmbiguousConversions = true; 7179 } 7180 7181 // If this is a viable builtin, print it. 7182 NoteBuiltinOperatorCandidate(S, Opc, OpLoc, Cand); 7183 } 7184 } 7185 7186 if (I != E) 7187 S.Diag(OpLoc, diag::note_ovl_too_many_candidates) << int(E - I); 7188} 7189 7190// [PossiblyAFunctionType] --> [Return] 7191// NonFunctionType --> NonFunctionType 7192// R (A) --> R(A) 7193// R (*)(A) --> R (A) 7194// R (&)(A) --> R (A) 7195// R (S::*)(A) --> R (A) 7196QualType Sema::ExtractUnqualifiedFunctionType(QualType PossiblyAFunctionType) { 7197 QualType Ret = PossiblyAFunctionType; 7198 if (const PointerType *ToTypePtr = 7199 PossiblyAFunctionType->getAs<PointerType>()) 7200 Ret = ToTypePtr->getPointeeType(); 7201 else if (const ReferenceType *ToTypeRef = 7202 PossiblyAFunctionType->getAs<ReferenceType>()) 7203 Ret = ToTypeRef->getPointeeType(); 7204 else if (const MemberPointerType *MemTypePtr = 7205 PossiblyAFunctionType->getAs<MemberPointerType>()) 7206 Ret = MemTypePtr->getPointeeType(); 7207 Ret = 7208 Context.getCanonicalType(Ret).getUnqualifiedType(); 7209 return Ret; 7210} 7211 7212// A helper class to help with address of function resolution 7213// - allows us to avoid passing around all those ugly parameters 7214class AddressOfFunctionResolver 7215{ 7216 Sema& S; 7217 Expr* SourceExpr; 7218 const QualType& TargetType; 7219 QualType TargetFunctionType; // Extracted function type from target type 7220 7221 bool Complain; 7222 //DeclAccessPair& ResultFunctionAccessPair; 7223 ASTContext& Context; 7224 7225 bool TargetTypeIsNonStaticMemberFunction; 7226 bool FoundNonTemplateFunction; 7227 7228 OverloadExpr::FindResult OvlExprInfo; 7229 OverloadExpr *OvlExpr; 7230 TemplateArgumentListInfo OvlExplicitTemplateArgs; 7231 llvm::SmallVector<std::pair<DeclAccessPair, FunctionDecl*>, 4> Matches; 7232 7233public: 7234 AddressOfFunctionResolver(Sema &S, Expr* SourceExpr, 7235 const QualType& TargetType, bool Complain) 7236 : S(S), SourceExpr(SourceExpr), TargetType(TargetType), 7237 Complain(Complain), Context(S.getASTContext()), 7238 TargetTypeIsNonStaticMemberFunction( 7239 !!TargetType->getAs<MemberPointerType>()), 7240 FoundNonTemplateFunction(false), 7241 OvlExprInfo(OverloadExpr::find(SourceExpr)), 7242 OvlExpr(OvlExprInfo.Expression) 7243 { 7244 ExtractUnqualifiedFunctionTypeFromTargetType(); 7245 7246 if (!TargetFunctionType->isFunctionType()) { 7247 if (OvlExpr->hasExplicitTemplateArgs()) { 7248 DeclAccessPair dap; 7249 if (FunctionDecl* Fn = S.ResolveSingleFunctionTemplateSpecialization( 7250 OvlExpr, false, &dap) ) { 7251 7252 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 7253 if (!Method->isStatic()) { 7254 // If the target type is a non-function type and the function 7255 // found is a non-static member function, pretend as if that was 7256 // the target, it's the only possible type to end up with. 7257 TargetTypeIsNonStaticMemberFunction = true; 7258 7259 // And skip adding the function if its not in the proper form. 7260 // We'll diagnose this due to an empty set of functions. 7261 if (!OvlExprInfo.HasFormOfMemberPointer) 7262 return; 7263 } 7264 } 7265 7266 Matches.push_back(std::make_pair(dap,Fn)); 7267 } 7268 } 7269 return; 7270 } 7271 7272 if (OvlExpr->hasExplicitTemplateArgs()) 7273 OvlExpr->getExplicitTemplateArgs().copyInto(OvlExplicitTemplateArgs); 7274 7275 if (FindAllFunctionsThatMatchTargetTypeExactly()) { 7276 // C++ [over.over]p4: 7277 // If more than one function is selected, [...] 7278 if (Matches.size() > 1) { 7279 if (FoundNonTemplateFunction) 7280 EliminateAllTemplateMatches(); 7281 else 7282 EliminateAllExceptMostSpecializedTemplate(); 7283 } 7284 } 7285 } 7286 7287private: 7288 bool isTargetTypeAFunction() const { 7289 return TargetFunctionType->isFunctionType(); 7290 } 7291 7292 // [ToType] [Return] 7293 7294 // R (*)(A) --> R (A), IsNonStaticMemberFunction = false 7295 // R (&)(A) --> R (A), IsNonStaticMemberFunction = false 7296 // R (S::*)(A) --> R (A), IsNonStaticMemberFunction = true 7297 void inline ExtractUnqualifiedFunctionTypeFromTargetType() { 7298 TargetFunctionType = S.ExtractUnqualifiedFunctionType(TargetType); 7299 } 7300 7301 // return true if any matching specializations were found 7302 bool AddMatchingTemplateFunction(FunctionTemplateDecl* FunctionTemplate, 7303 const DeclAccessPair& CurAccessFunPair) { 7304 if (CXXMethodDecl *Method 7305 = dyn_cast<CXXMethodDecl>(FunctionTemplate->getTemplatedDecl())) { 7306 // Skip non-static function templates when converting to pointer, and 7307 // static when converting to member pointer. 7308 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 7309 return false; 7310 } 7311 else if (TargetTypeIsNonStaticMemberFunction) 7312 return false; 7313 7314 // C++ [over.over]p2: 7315 // If the name is a function template, template argument deduction is 7316 // done (14.8.2.2), and if the argument deduction succeeds, the 7317 // resulting template argument list is used to generate a single 7318 // function template specialization, which is added to the set of 7319 // overloaded functions considered. 7320 FunctionDecl *Specialization = 0; 7321 TemplateDeductionInfo Info(Context, OvlExpr->getNameLoc()); 7322 if (Sema::TemplateDeductionResult Result 7323 = S.DeduceTemplateArguments(FunctionTemplate, 7324 &OvlExplicitTemplateArgs, 7325 TargetFunctionType, Specialization, 7326 Info)) { 7327 // FIXME: make a note of the failed deduction for diagnostics. 7328 (void)Result; 7329 return false; 7330 } 7331 7332 // Template argument deduction ensures that we have an exact match. 7333 // This function template specicalization works. 7334 Specialization = cast<FunctionDecl>(Specialization->getCanonicalDecl()); 7335 assert(TargetFunctionType 7336 == Context.getCanonicalType(Specialization->getType())); 7337 Matches.push_back(std::make_pair(CurAccessFunPair, Specialization)); 7338 return true; 7339 } 7340 7341 bool AddMatchingNonTemplateFunction(NamedDecl* Fn, 7342 const DeclAccessPair& CurAccessFunPair) { 7343 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 7344 // Skip non-static functions when converting to pointer, and static 7345 // when converting to member pointer. 7346 if (Method->isStatic() == TargetTypeIsNonStaticMemberFunction) 7347 return false; 7348 } 7349 else if (TargetTypeIsNonStaticMemberFunction) 7350 return false; 7351 7352 if (FunctionDecl *FunDecl = dyn_cast<FunctionDecl>(Fn)) { 7353 QualType ResultTy; 7354 if (Context.hasSameUnqualifiedType(TargetFunctionType, 7355 FunDecl->getType()) || 7356 IsNoReturnConversion(Context, FunDecl->getType(), TargetFunctionType, 7357 ResultTy)) { 7358 Matches.push_back(std::make_pair(CurAccessFunPair, 7359 cast<FunctionDecl>(FunDecl->getCanonicalDecl()))); 7360 FoundNonTemplateFunction = true; 7361 return true; 7362 } 7363 } 7364 7365 return false; 7366 } 7367 7368 bool FindAllFunctionsThatMatchTargetTypeExactly() { 7369 bool Ret = false; 7370 7371 // If the overload expression doesn't have the form of a pointer to 7372 // member, don't try to convert it to a pointer-to-member type. 7373 if (IsInvalidFormOfPointerToMemberFunction()) 7374 return false; 7375 7376 for (UnresolvedSetIterator I = OvlExpr->decls_begin(), 7377 E = OvlExpr->decls_end(); 7378 I != E; ++I) { 7379 // Look through any using declarations to find the underlying function. 7380 NamedDecl *Fn = (*I)->getUnderlyingDecl(); 7381 7382 // C++ [over.over]p3: 7383 // Non-member functions and static member functions match 7384 // targets of type "pointer-to-function" or "reference-to-function." 7385 // Nonstatic member functions match targets of 7386 // type "pointer-to-member-function." 7387 // Note that according to DR 247, the containing class does not matter. 7388 if (FunctionTemplateDecl *FunctionTemplate 7389 = dyn_cast<FunctionTemplateDecl>(Fn)) { 7390 if (AddMatchingTemplateFunction(FunctionTemplate, I.getPair())) 7391 Ret = true; 7392 } 7393 // If we have explicit template arguments supplied, skip non-templates. 7394 else if (!OvlExpr->hasExplicitTemplateArgs() && 7395 AddMatchingNonTemplateFunction(Fn, I.getPair())) 7396 Ret = true; 7397 } 7398 assert(Ret || Matches.empty()); 7399 return Ret; 7400 } 7401 7402 void EliminateAllExceptMostSpecializedTemplate() { 7403 // [...] and any given function template specialization F1 is 7404 // eliminated if the set contains a second function template 7405 // specialization whose function template is more specialized 7406 // than the function template of F1 according to the partial 7407 // ordering rules of 14.5.5.2. 7408 7409 // The algorithm specified above is quadratic. We instead use a 7410 // two-pass algorithm (similar to the one used to identify the 7411 // best viable function in an overload set) that identifies the 7412 // best function template (if it exists). 7413 7414 UnresolvedSet<4> MatchesCopy; // TODO: avoid! 7415 for (unsigned I = 0, E = Matches.size(); I != E; ++I) 7416 MatchesCopy.addDecl(Matches[I].second, Matches[I].first.getAccess()); 7417 7418 UnresolvedSetIterator Result = 7419 S.getMostSpecialized(MatchesCopy.begin(), MatchesCopy.end(), 7420 TPOC_Other, 0, SourceExpr->getLocStart(), 7421 S.PDiag(), 7422 S.PDiag(diag::err_addr_ovl_ambiguous) 7423 << Matches[0].second->getDeclName(), 7424 S.PDiag(diag::note_ovl_candidate) 7425 << (unsigned) oc_function_template, 7426 Complain); 7427 7428 if (Result != MatchesCopy.end()) { 7429 // Make it the first and only element 7430 Matches[0].first = Matches[Result - MatchesCopy.begin()].first; 7431 Matches[0].second = cast<FunctionDecl>(*Result); 7432 Matches.resize(1); 7433 } 7434 } 7435 7436 void EliminateAllTemplateMatches() { 7437 // [...] any function template specializations in the set are 7438 // eliminated if the set also contains a non-template function, [...] 7439 for (unsigned I = 0, N = Matches.size(); I != N; ) { 7440 if (Matches[I].second->getPrimaryTemplate() == 0) 7441 ++I; 7442 else { 7443 Matches[I] = Matches[--N]; 7444 Matches.set_size(N); 7445 } 7446 } 7447 } 7448 7449public: 7450 void ComplainNoMatchesFound() const { 7451 assert(Matches.empty()); 7452 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_no_viable) 7453 << OvlExpr->getName() << TargetFunctionType 7454 << OvlExpr->getSourceRange(); 7455 S.NoteAllOverloadCandidates(OvlExpr); 7456 } 7457 7458 bool IsInvalidFormOfPointerToMemberFunction() const { 7459 return TargetTypeIsNonStaticMemberFunction && 7460 !OvlExprInfo.HasFormOfMemberPointer; 7461 } 7462 7463 void ComplainIsInvalidFormOfPointerToMemberFunction() const { 7464 // TODO: Should we condition this on whether any functions might 7465 // have matched, or is it more appropriate to do that in callers? 7466 // TODO: a fixit wouldn't hurt. 7467 S.Diag(OvlExpr->getNameLoc(), diag::err_addr_ovl_no_qualifier) 7468 << TargetType << OvlExpr->getSourceRange(); 7469 } 7470 7471 void ComplainOfInvalidConversion() const { 7472 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_not_func_ptrref) 7473 << OvlExpr->getName() << TargetType; 7474 } 7475 7476 void ComplainMultipleMatchesFound() const { 7477 assert(Matches.size() > 1); 7478 S.Diag(OvlExpr->getLocStart(), diag::err_addr_ovl_ambiguous) 7479 << OvlExpr->getName() 7480 << OvlExpr->getSourceRange(); 7481 S.NoteAllOverloadCandidates(OvlExpr); 7482 } 7483 7484 int getNumMatches() const { return Matches.size(); } 7485 7486 FunctionDecl* getMatchingFunctionDecl() const { 7487 if (Matches.size() != 1) return 0; 7488 return Matches[0].second; 7489 } 7490 7491 const DeclAccessPair* getMatchingFunctionAccessPair() const { 7492 if (Matches.size() != 1) return 0; 7493 return &Matches[0].first; 7494 } 7495}; 7496 7497/// ResolveAddressOfOverloadedFunction - Try to resolve the address of 7498/// an overloaded function (C++ [over.over]), where @p From is an 7499/// expression with overloaded function type and @p ToType is the type 7500/// we're trying to resolve to. For example: 7501/// 7502/// @code 7503/// int f(double); 7504/// int f(int); 7505/// 7506/// int (*pfd)(double) = f; // selects f(double) 7507/// @endcode 7508/// 7509/// This routine returns the resulting FunctionDecl if it could be 7510/// resolved, and NULL otherwise. When @p Complain is true, this 7511/// routine will emit diagnostics if there is an error. 7512FunctionDecl * 7513Sema::ResolveAddressOfOverloadedFunction(Expr *AddressOfExpr, QualType TargetType, 7514 bool Complain, 7515 DeclAccessPair &FoundResult) { 7516 7517 assert(AddressOfExpr->getType() == Context.OverloadTy); 7518 7519 AddressOfFunctionResolver Resolver(*this, AddressOfExpr, TargetType, Complain); 7520 int NumMatches = Resolver.getNumMatches(); 7521 FunctionDecl* Fn = 0; 7522 if ( NumMatches == 0 && Complain) { 7523 if (Resolver.IsInvalidFormOfPointerToMemberFunction()) 7524 Resolver.ComplainIsInvalidFormOfPointerToMemberFunction(); 7525 else 7526 Resolver.ComplainNoMatchesFound(); 7527 } 7528 else if (NumMatches > 1 && Complain) 7529 Resolver.ComplainMultipleMatchesFound(); 7530 else if (NumMatches == 1) { 7531 Fn = Resolver.getMatchingFunctionDecl(); 7532 assert(Fn); 7533 FoundResult = *Resolver.getMatchingFunctionAccessPair(); 7534 MarkDeclarationReferenced(AddressOfExpr->getLocStart(), Fn); 7535 if (Complain) 7536 CheckAddressOfMemberAccess(AddressOfExpr, FoundResult); 7537 } 7538 7539 return Fn; 7540} 7541 7542/// \brief Given an expression that refers to an overloaded function, try to 7543/// resolve that overloaded function expression down to a single function. 7544/// 7545/// This routine can only resolve template-ids that refer to a single function 7546/// template, where that template-id refers to a single template whose template 7547/// arguments are either provided by the template-id or have defaults, 7548/// as described in C++0x [temp.arg.explicit]p3. 7549FunctionDecl * 7550Sema::ResolveSingleFunctionTemplateSpecialization(OverloadExpr *ovl, 7551 bool Complain, 7552 DeclAccessPair *FoundResult) { 7553 // C++ [over.over]p1: 7554 // [...] [Note: any redundant set of parentheses surrounding the 7555 // overloaded function name is ignored (5.1). ] 7556 // C++ [over.over]p1: 7557 // [...] The overloaded function name can be preceded by the & 7558 // operator. 7559 7560 // If we didn't actually find any template-ids, we're done. 7561 if (!ovl->hasExplicitTemplateArgs()) 7562 return 0; 7563 7564 TemplateArgumentListInfo ExplicitTemplateArgs; 7565 ovl->getExplicitTemplateArgs().copyInto(ExplicitTemplateArgs); 7566 7567 // Look through all of the overloaded functions, searching for one 7568 // whose type matches exactly. 7569 FunctionDecl *Matched = 0; 7570 for (UnresolvedSetIterator I = ovl->decls_begin(), 7571 E = ovl->decls_end(); I != E; ++I) { 7572 // C++0x [temp.arg.explicit]p3: 7573 // [...] In contexts where deduction is done and fails, or in contexts 7574 // where deduction is not done, if a template argument list is 7575 // specified and it, along with any default template arguments, 7576 // identifies a single function template specialization, then the 7577 // template-id is an lvalue for the function template specialization. 7578 FunctionTemplateDecl *FunctionTemplate 7579 = cast<FunctionTemplateDecl>((*I)->getUnderlyingDecl()); 7580 7581 // C++ [over.over]p2: 7582 // If the name is a function template, template argument deduction is 7583 // done (14.8.2.2), and if the argument deduction succeeds, the 7584 // resulting template argument list is used to generate a single 7585 // function template specialization, which is added to the set of 7586 // overloaded functions considered. 7587 FunctionDecl *Specialization = 0; 7588 TemplateDeductionInfo Info(Context, ovl->getNameLoc()); 7589 if (TemplateDeductionResult Result 7590 = DeduceTemplateArguments(FunctionTemplate, &ExplicitTemplateArgs, 7591 Specialization, Info)) { 7592 // FIXME: make a note of the failed deduction for diagnostics. 7593 (void)Result; 7594 continue; 7595 } 7596 7597 assert(Specialization && "no specialization and no error?"); 7598 7599 // Multiple matches; we can't resolve to a single declaration. 7600 if (Matched) { 7601 if (Complain) { 7602 Diag(ovl->getExprLoc(), diag::err_addr_ovl_ambiguous) 7603 << ovl->getName(); 7604 NoteAllOverloadCandidates(ovl); 7605 } 7606 return 0; 7607 } 7608 7609 Matched = Specialization; 7610 if (FoundResult) *FoundResult = I.getPair(); 7611 } 7612 7613 return Matched; 7614} 7615 7616 7617 7618 7619// Resolve and fix an overloaded expression that 7620// can be resolved because it identifies a single function 7621// template specialization 7622// Last three arguments should only be supplied if Complain = true 7623ExprResult Sema::ResolveAndFixSingleFunctionTemplateSpecialization( 7624 Expr *SrcExpr, bool doFunctionPointerConverion, bool complain, 7625 const SourceRange& OpRangeForComplaining, 7626 QualType DestTypeForComplaining, 7627 unsigned DiagIDForComplaining) { 7628 assert(SrcExpr->getType() == Context.OverloadTy); 7629 7630 OverloadExpr::FindResult ovl = OverloadExpr::find(SrcExpr); 7631 7632 DeclAccessPair found; 7633 ExprResult SingleFunctionExpression; 7634 if (FunctionDecl *fn = ResolveSingleFunctionTemplateSpecialization( 7635 ovl.Expression, /*complain*/ false, &found)) { 7636 if (DiagnoseUseOfDecl(fn, SrcExpr->getSourceRange().getBegin())) 7637 return ExprError(); 7638 7639 // It is only correct to resolve to an instance method if we're 7640 // resolving a form that's permitted to be a pointer to member. 7641 // Otherwise we'll end up making a bound member expression, which 7642 // is illegal in all the contexts we resolve like this. 7643 if (!ovl.HasFormOfMemberPointer && 7644 isa<CXXMethodDecl>(fn) && 7645 cast<CXXMethodDecl>(fn)->isInstance()) { 7646 if (complain) { 7647 Diag(ovl.Expression->getExprLoc(), 7648 diag::err_invalid_use_of_bound_member_func) 7649 << ovl.Expression->getSourceRange(); 7650 // TODO: I believe we only end up here if there's a mix of 7651 // static and non-static candidates (otherwise the expression 7652 // would have 'bound member' type, not 'overload' type). 7653 // Ideally we would note which candidate was chosen and why 7654 // the static candidates were rejected. 7655 } 7656 7657 return ExprError(); 7658 } 7659 7660 // Fix the expresion to refer to 'fn'. 7661 SingleFunctionExpression = 7662 Owned(FixOverloadedFunctionReference(SrcExpr, found, fn)); 7663 7664 // If desired, do function-to-pointer decay. 7665 if (doFunctionPointerConverion) 7666 SingleFunctionExpression = 7667 DefaultFunctionArrayLvalueConversion(SingleFunctionExpression.take()); 7668 } 7669 7670 if (!SingleFunctionExpression.isUsable()) { 7671 if (complain) { 7672 Diag(OpRangeForComplaining.getBegin(), DiagIDForComplaining) 7673 << ovl.Expression->getName() 7674 << DestTypeForComplaining 7675 << OpRangeForComplaining 7676 << ovl.Expression->getQualifierLoc().getSourceRange(); 7677 NoteAllOverloadCandidates(SrcExpr); 7678 } 7679 return ExprError(); 7680 } 7681 7682 return SingleFunctionExpression; 7683} 7684 7685/// \brief Add a single candidate to the overload set. 7686static void AddOverloadedCallCandidate(Sema &S, 7687 DeclAccessPair FoundDecl, 7688 TemplateArgumentListInfo *ExplicitTemplateArgs, 7689 Expr **Args, unsigned NumArgs, 7690 OverloadCandidateSet &CandidateSet, 7691 bool PartialOverloading) { 7692 NamedDecl *Callee = FoundDecl.getDecl(); 7693 if (isa<UsingShadowDecl>(Callee)) 7694 Callee = cast<UsingShadowDecl>(Callee)->getTargetDecl(); 7695 7696 if (FunctionDecl *Func = dyn_cast<FunctionDecl>(Callee)) { 7697 assert(!ExplicitTemplateArgs && "Explicit template arguments?"); 7698 S.AddOverloadCandidate(Func, FoundDecl, Args, NumArgs, CandidateSet, 7699 false, PartialOverloading); 7700 return; 7701 } 7702 7703 if (FunctionTemplateDecl *FuncTemplate 7704 = dyn_cast<FunctionTemplateDecl>(Callee)) { 7705 S.AddTemplateOverloadCandidate(FuncTemplate, FoundDecl, 7706 ExplicitTemplateArgs, 7707 Args, NumArgs, CandidateSet); 7708 return; 7709 } 7710 7711 assert(false && "unhandled case in overloaded call candidate"); 7712 7713 // do nothing? 7714} 7715 7716/// \brief Add the overload candidates named by callee and/or found by argument 7717/// dependent lookup to the given overload set. 7718void Sema::AddOverloadedCallCandidates(UnresolvedLookupExpr *ULE, 7719 Expr **Args, unsigned NumArgs, 7720 OverloadCandidateSet &CandidateSet, 7721 bool PartialOverloading) { 7722 7723#ifndef NDEBUG 7724 // Verify that ArgumentDependentLookup is consistent with the rules 7725 // in C++0x [basic.lookup.argdep]p3: 7726 // 7727 // Let X be the lookup set produced by unqualified lookup (3.4.1) 7728 // and let Y be the lookup set produced by argument dependent 7729 // lookup (defined as follows). If X contains 7730 // 7731 // -- a declaration of a class member, or 7732 // 7733 // -- a block-scope function declaration that is not a 7734 // using-declaration, or 7735 // 7736 // -- a declaration that is neither a function or a function 7737 // template 7738 // 7739 // then Y is empty. 7740 7741 if (ULE->requiresADL()) { 7742 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 7743 E = ULE->decls_end(); I != E; ++I) { 7744 assert(!(*I)->getDeclContext()->isRecord()); 7745 assert(isa<UsingShadowDecl>(*I) || 7746 !(*I)->getDeclContext()->isFunctionOrMethod()); 7747 assert((*I)->getUnderlyingDecl()->isFunctionOrFunctionTemplate()); 7748 } 7749 } 7750#endif 7751 7752 // It would be nice to avoid this copy. 7753 TemplateArgumentListInfo TABuffer; 7754 TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 7755 if (ULE->hasExplicitTemplateArgs()) { 7756 ULE->copyTemplateArgumentsInto(TABuffer); 7757 ExplicitTemplateArgs = &TABuffer; 7758 } 7759 7760 for (UnresolvedLookupExpr::decls_iterator I = ULE->decls_begin(), 7761 E = ULE->decls_end(); I != E; ++I) 7762 AddOverloadedCallCandidate(*this, I.getPair(), ExplicitTemplateArgs, 7763 Args, NumArgs, CandidateSet, 7764 PartialOverloading); 7765 7766 if (ULE->requiresADL()) 7767 AddArgumentDependentLookupCandidates(ULE->getName(), /*Operator*/ false, 7768 Args, NumArgs, 7769 ExplicitTemplateArgs, 7770 CandidateSet, 7771 PartialOverloading, 7772 ULE->isStdAssociatedNamespace()); 7773} 7774 7775/// Attempts to recover from a call where no functions were found. 7776/// 7777/// Returns true if new candidates were found. 7778static ExprResult 7779BuildRecoveryCallExpr(Sema &SemaRef, Scope *S, Expr *Fn, 7780 UnresolvedLookupExpr *ULE, 7781 SourceLocation LParenLoc, 7782 Expr **Args, unsigned NumArgs, 7783 SourceLocation RParenLoc) { 7784 7785 CXXScopeSpec SS; 7786 SS.Adopt(ULE->getQualifierLoc()); 7787 7788 TemplateArgumentListInfo TABuffer; 7789 const TemplateArgumentListInfo *ExplicitTemplateArgs = 0; 7790 if (ULE->hasExplicitTemplateArgs()) { 7791 ULE->copyTemplateArgumentsInto(TABuffer); 7792 ExplicitTemplateArgs = &TABuffer; 7793 } 7794 7795 LookupResult R(SemaRef, ULE->getName(), ULE->getNameLoc(), 7796 Sema::LookupOrdinaryName); 7797 if (SemaRef.DiagnoseEmptyLookup(S, SS, R, Sema::CTC_Expression)) 7798 return ExprError(); 7799 7800 assert(!R.empty() && "lookup results empty despite recovery"); 7801 7802 // Build an implicit member call if appropriate. Just drop the 7803 // casts and such from the call, we don't really care. 7804 ExprResult NewFn = ExprError(); 7805 if ((*R.begin())->isCXXClassMember()) 7806 NewFn = SemaRef.BuildPossibleImplicitMemberExpr(SS, R, 7807 ExplicitTemplateArgs); 7808 else if (ExplicitTemplateArgs) 7809 NewFn = SemaRef.BuildTemplateIdExpr(SS, R, false, *ExplicitTemplateArgs); 7810 else 7811 NewFn = SemaRef.BuildDeclarationNameExpr(SS, R, false); 7812 7813 if (NewFn.isInvalid()) 7814 return ExprError(); 7815 7816 // This shouldn't cause an infinite loop because we're giving it 7817 // an expression with non-empty lookup results, which should never 7818 // end up here. 7819 return SemaRef.ActOnCallExpr(/*Scope*/ 0, NewFn.take(), LParenLoc, 7820 MultiExprArg(Args, NumArgs), RParenLoc); 7821} 7822 7823/// ResolveOverloadedCallFn - Given the call expression that calls Fn 7824/// (which eventually refers to the declaration Func) and the call 7825/// arguments Args/NumArgs, attempt to resolve the function call down 7826/// to a specific function. If overload resolution succeeds, returns 7827/// the function declaration produced by overload 7828/// resolution. Otherwise, emits diagnostics, deletes all of the 7829/// arguments and Fn, and returns NULL. 7830ExprResult 7831Sema::BuildOverloadedCallExpr(Scope *S, Expr *Fn, UnresolvedLookupExpr *ULE, 7832 SourceLocation LParenLoc, 7833 Expr **Args, unsigned NumArgs, 7834 SourceLocation RParenLoc, 7835 Expr *ExecConfig) { 7836#ifndef NDEBUG 7837 if (ULE->requiresADL()) { 7838 // To do ADL, we must have found an unqualified name. 7839 assert(!ULE->getQualifier() && "qualified name with ADL"); 7840 7841 // We don't perform ADL for implicit declarations of builtins. 7842 // Verify that this was correctly set up. 7843 FunctionDecl *F; 7844 if (ULE->decls_begin() + 1 == ULE->decls_end() && 7845 (F = dyn_cast<FunctionDecl>(*ULE->decls_begin())) && 7846 F->getBuiltinID() && F->isImplicit()) 7847 assert(0 && "performing ADL for builtin"); 7848 7849 // We don't perform ADL in C. 7850 assert(getLangOptions().CPlusPlus && "ADL enabled in C"); 7851 } else 7852 assert(!ULE->isStdAssociatedNamespace() && 7853 "std is associated namespace but not doing ADL"); 7854#endif 7855 7856 OverloadCandidateSet CandidateSet(Fn->getExprLoc()); 7857 7858 // Add the functions denoted by the callee to the set of candidate 7859 // functions, including those from argument-dependent lookup. 7860 AddOverloadedCallCandidates(ULE, Args, NumArgs, CandidateSet); 7861 7862 // If we found nothing, try to recover. 7863 // AddRecoveryCallCandidates diagnoses the error itself, so we just 7864 // bailout out if it fails. 7865 if (CandidateSet.empty()) 7866 return BuildRecoveryCallExpr(*this, S, Fn, ULE, LParenLoc, Args, NumArgs, 7867 RParenLoc); 7868 7869 OverloadCandidateSet::iterator Best; 7870 switch (CandidateSet.BestViableFunction(*this, Fn->getLocStart(), Best)) { 7871 case OR_Success: { 7872 FunctionDecl *FDecl = Best->Function; 7873 MarkDeclarationReferenced(Fn->getExprLoc(), FDecl); 7874 CheckUnresolvedLookupAccess(ULE, Best->FoundDecl); 7875 DiagnoseUseOfDecl(FDecl? FDecl : Best->FoundDecl.getDecl(), 7876 ULE->getNameLoc()); 7877 Fn = FixOverloadedFunctionReference(Fn, Best->FoundDecl, FDecl); 7878 return BuildResolvedCallExpr(Fn, FDecl, LParenLoc, Args, NumArgs, RParenLoc, 7879 ExecConfig); 7880 } 7881 7882 case OR_No_Viable_Function: 7883 Diag(Fn->getSourceRange().getBegin(), 7884 diag::err_ovl_no_viable_function_in_call) 7885 << ULE->getName() << Fn->getSourceRange(); 7886 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 7887 break; 7888 7889 case OR_Ambiguous: 7890 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_ambiguous_call) 7891 << ULE->getName() << Fn->getSourceRange(); 7892 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 7893 break; 7894 7895 case OR_Deleted: 7896 { 7897 Diag(Fn->getSourceRange().getBegin(), diag::err_ovl_deleted_call) 7898 << Best->Function->isDeleted() 7899 << ULE->getName() 7900 << getDeletedOrUnavailableSuffix(Best->Function) 7901 << Fn->getSourceRange(); 7902 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 7903 } 7904 break; 7905 } 7906 7907 // Overload resolution failed. 7908 return ExprError(); 7909} 7910 7911static bool IsOverloaded(const UnresolvedSetImpl &Functions) { 7912 return Functions.size() > 1 || 7913 (Functions.size() == 1 && isa<FunctionTemplateDecl>(*Functions.begin())); 7914} 7915 7916/// \brief Create a unary operation that may resolve to an overloaded 7917/// operator. 7918/// 7919/// \param OpLoc The location of the operator itself (e.g., '*'). 7920/// 7921/// \param OpcIn The UnaryOperator::Opcode that describes this 7922/// operator. 7923/// 7924/// \param Functions The set of non-member functions that will be 7925/// considered by overload resolution. The caller needs to build this 7926/// set based on the context using, e.g., 7927/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 7928/// set should not contain any member functions; those will be added 7929/// by CreateOverloadedUnaryOp(). 7930/// 7931/// \param input The input argument. 7932ExprResult 7933Sema::CreateOverloadedUnaryOp(SourceLocation OpLoc, unsigned OpcIn, 7934 const UnresolvedSetImpl &Fns, 7935 Expr *Input) { 7936 UnaryOperator::Opcode Opc = static_cast<UnaryOperator::Opcode>(OpcIn); 7937 7938 OverloadedOperatorKind Op = UnaryOperator::getOverloadedOperator(Opc); 7939 assert(Op != OO_None && "Invalid opcode for overloaded unary operator"); 7940 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 7941 // TODO: provide better source location info. 7942 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 7943 7944 if (Input->getObjectKind() == OK_ObjCProperty) { 7945 ExprResult Result = ConvertPropertyForRValue(Input); 7946 if (Result.isInvalid()) 7947 return ExprError(); 7948 Input = Result.take(); 7949 } 7950 7951 Expr *Args[2] = { Input, 0 }; 7952 unsigned NumArgs = 1; 7953 7954 // For post-increment and post-decrement, add the implicit '0' as 7955 // the second argument, so that we know this is a post-increment or 7956 // post-decrement. 7957 if (Opc == UO_PostInc || Opc == UO_PostDec) { 7958 llvm::APSInt Zero(Context.getTypeSize(Context.IntTy), false); 7959 Args[1] = IntegerLiteral::Create(Context, Zero, Context.IntTy, 7960 SourceLocation()); 7961 NumArgs = 2; 7962 } 7963 7964 if (Input->isTypeDependent()) { 7965 if (Fns.empty()) 7966 return Owned(new (Context) UnaryOperator(Input, 7967 Opc, 7968 Context.DependentTy, 7969 VK_RValue, OK_Ordinary, 7970 OpLoc)); 7971 7972 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 7973 UnresolvedLookupExpr *Fn 7974 = UnresolvedLookupExpr::Create(Context, NamingClass, 7975 NestedNameSpecifierLoc(), OpNameInfo, 7976 /*ADL*/ true, IsOverloaded(Fns), 7977 Fns.begin(), Fns.end()); 7978 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 7979 &Args[0], NumArgs, 7980 Context.DependentTy, 7981 VK_RValue, 7982 OpLoc)); 7983 } 7984 7985 // Build an empty overload set. 7986 OverloadCandidateSet CandidateSet(OpLoc); 7987 7988 // Add the candidates from the given function set. 7989 AddFunctionCandidates(Fns, &Args[0], NumArgs, CandidateSet, false); 7990 7991 // Add operator candidates that are member functions. 7992 AddMemberOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 7993 7994 // Add candidates from ADL. 7995 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 7996 Args, NumArgs, 7997 /*ExplicitTemplateArgs*/ 0, 7998 CandidateSet); 7999 8000 // Add builtin operator candidates. 8001 AddBuiltinOperatorCandidates(Op, OpLoc, &Args[0], NumArgs, CandidateSet); 8002 8003 // Perform overload resolution. 8004 OverloadCandidateSet::iterator Best; 8005 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8006 case OR_Success: { 8007 // We found a built-in operator or an overloaded operator. 8008 FunctionDecl *FnDecl = Best->Function; 8009 8010 if (FnDecl) { 8011 // We matched an overloaded operator. Build a call to that 8012 // operator. 8013 8014 MarkDeclarationReferenced(OpLoc, FnDecl); 8015 8016 // Convert the arguments. 8017 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 8018 CheckMemberOperatorAccess(OpLoc, Args[0], 0, Best->FoundDecl); 8019 8020 ExprResult InputRes = 8021 PerformObjectArgumentInitialization(Input, /*Qualifier=*/0, 8022 Best->FoundDecl, Method); 8023 if (InputRes.isInvalid()) 8024 return ExprError(); 8025 Input = InputRes.take(); 8026 } else { 8027 // Convert the arguments. 8028 ExprResult InputInit 8029 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 8030 Context, 8031 FnDecl->getParamDecl(0)), 8032 SourceLocation(), 8033 Input); 8034 if (InputInit.isInvalid()) 8035 return ExprError(); 8036 Input = InputInit.take(); 8037 } 8038 8039 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 8040 8041 // Determine the result type. 8042 QualType ResultTy = FnDecl->getResultType(); 8043 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8044 ResultTy = ResultTy.getNonLValueExprType(Context); 8045 8046 // Build the actual expression node. 8047 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl); 8048 if (FnExpr.isInvalid()) 8049 return ExprError(); 8050 8051 Args[0] = Input; 8052 CallExpr *TheCall = 8053 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 8054 Args, NumArgs, ResultTy, VK, OpLoc); 8055 8056 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 8057 FnDecl)) 8058 return ExprError(); 8059 8060 return MaybeBindToTemporary(TheCall); 8061 } else { 8062 // We matched a built-in operator. Convert the arguments, then 8063 // break out so that we will build the appropriate built-in 8064 // operator node. 8065 ExprResult InputRes = 8066 PerformImplicitConversion(Input, Best->BuiltinTypes.ParamTypes[0], 8067 Best->Conversions[0], AA_Passing); 8068 if (InputRes.isInvalid()) 8069 return ExprError(); 8070 Input = InputRes.take(); 8071 break; 8072 } 8073 } 8074 8075 case OR_No_Viable_Function: 8076 // No viable function; fall through to handling this as a 8077 // built-in operator, which will produce an error message for us. 8078 break; 8079 8080 case OR_Ambiguous: 8081 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 8082 << UnaryOperator::getOpcodeStr(Opc) 8083 << Input->getType() 8084 << Input->getSourceRange(); 8085 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, 8086 Args, NumArgs, 8087 UnaryOperator::getOpcodeStr(Opc), OpLoc); 8088 return ExprError(); 8089 8090 case OR_Deleted: 8091 Diag(OpLoc, diag::err_ovl_deleted_oper) 8092 << Best->Function->isDeleted() 8093 << UnaryOperator::getOpcodeStr(Opc) 8094 << getDeletedOrUnavailableSuffix(Best->Function) 8095 << Input->getSourceRange(); 8096 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8097 return ExprError(); 8098 } 8099 8100 // Either we found no viable overloaded operator or we matched a 8101 // built-in operator. In either case, fall through to trying to 8102 // build a built-in operation. 8103 return CreateBuiltinUnaryOp(OpLoc, Opc, Input); 8104} 8105 8106/// \brief Create a binary operation that may resolve to an overloaded 8107/// operator. 8108/// 8109/// \param OpLoc The location of the operator itself (e.g., '+'). 8110/// 8111/// \param OpcIn The BinaryOperator::Opcode that describes this 8112/// operator. 8113/// 8114/// \param Functions The set of non-member functions that will be 8115/// considered by overload resolution. The caller needs to build this 8116/// set based on the context using, e.g., 8117/// LookupOverloadedOperatorName() and ArgumentDependentLookup(). This 8118/// set should not contain any member functions; those will be added 8119/// by CreateOverloadedBinOp(). 8120/// 8121/// \param LHS Left-hand argument. 8122/// \param RHS Right-hand argument. 8123ExprResult 8124Sema::CreateOverloadedBinOp(SourceLocation OpLoc, 8125 unsigned OpcIn, 8126 const UnresolvedSetImpl &Fns, 8127 Expr *LHS, Expr *RHS) { 8128 Expr *Args[2] = { LHS, RHS }; 8129 LHS=RHS=0; //Please use only Args instead of LHS/RHS couple 8130 8131 BinaryOperator::Opcode Opc = static_cast<BinaryOperator::Opcode>(OpcIn); 8132 OverloadedOperatorKind Op = BinaryOperator::getOverloadedOperator(Opc); 8133 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op); 8134 8135 // If either side is type-dependent, create an appropriate dependent 8136 // expression. 8137 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 8138 if (Fns.empty()) { 8139 // If there are no functions to store, just build a dependent 8140 // BinaryOperator or CompoundAssignment. 8141 if (Opc <= BO_Assign || Opc > BO_OrAssign) 8142 return Owned(new (Context) BinaryOperator(Args[0], Args[1], Opc, 8143 Context.DependentTy, 8144 VK_RValue, OK_Ordinary, 8145 OpLoc)); 8146 8147 return Owned(new (Context) CompoundAssignOperator(Args[0], Args[1], Opc, 8148 Context.DependentTy, 8149 VK_LValue, 8150 OK_Ordinary, 8151 Context.DependentTy, 8152 Context.DependentTy, 8153 OpLoc)); 8154 } 8155 8156 // FIXME: save results of ADL from here? 8157 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8158 // TODO: provide better source location info in DNLoc component. 8159 DeclarationNameInfo OpNameInfo(OpName, OpLoc); 8160 UnresolvedLookupExpr *Fn 8161 = UnresolvedLookupExpr::Create(Context, NamingClass, 8162 NestedNameSpecifierLoc(), OpNameInfo, 8163 /*ADL*/ true, IsOverloaded(Fns), 8164 Fns.begin(), Fns.end()); 8165 return Owned(new (Context) CXXOperatorCallExpr(Context, Op, Fn, 8166 Args, 2, 8167 Context.DependentTy, 8168 VK_RValue, 8169 OpLoc)); 8170 } 8171 8172 // Always do property rvalue conversions on the RHS. 8173 if (Args[1]->getObjectKind() == OK_ObjCProperty) { 8174 ExprResult Result = ConvertPropertyForRValue(Args[1]); 8175 if (Result.isInvalid()) 8176 return ExprError(); 8177 Args[1] = Result.take(); 8178 } 8179 8180 // The LHS is more complicated. 8181 if (Args[0]->getObjectKind() == OK_ObjCProperty) { 8182 8183 // There's a tension for assignment operators between primitive 8184 // property assignment and the overloaded operators. 8185 if (BinaryOperator::isAssignmentOp(Opc)) { 8186 const ObjCPropertyRefExpr *PRE = LHS->getObjCProperty(); 8187 8188 // Is the property "logically" settable? 8189 bool Settable = (PRE->isExplicitProperty() || 8190 PRE->getImplicitPropertySetter()); 8191 8192 // To avoid gratuitously inventing semantics, use the primitive 8193 // unless it isn't. Thoughts in case we ever really care: 8194 // - If the property isn't logically settable, we have to 8195 // load and hope. 8196 // - If the property is settable and this is simple assignment, 8197 // we really should use the primitive. 8198 // - If the property is settable, then we could try overloading 8199 // on a generic lvalue of the appropriate type; if it works 8200 // out to a builtin candidate, we would do that same operation 8201 // on the property, and otherwise just error. 8202 if (Settable) 8203 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8204 } 8205 8206 ExprResult Result = ConvertPropertyForRValue(Args[0]); 8207 if (Result.isInvalid()) 8208 return ExprError(); 8209 Args[0] = Result.take(); 8210 } 8211 8212 // If this is the assignment operator, we only perform overload resolution 8213 // if the left-hand side is a class or enumeration type. This is actually 8214 // a hack. The standard requires that we do overload resolution between the 8215 // various built-in candidates, but as DR507 points out, this can lead to 8216 // problems. So we do it this way, which pretty much follows what GCC does. 8217 // Note that we go the traditional code path for compound assignment forms. 8218 if (Opc == BO_Assign && !Args[0]->getType()->isOverloadableType()) 8219 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8220 8221 // If this is the .* operator, which is not overloadable, just 8222 // create a built-in binary operator. 8223 if (Opc == BO_PtrMemD) 8224 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8225 8226 // Build an empty overload set. 8227 OverloadCandidateSet CandidateSet(OpLoc); 8228 8229 // Add the candidates from the given function set. 8230 AddFunctionCandidates(Fns, Args, 2, CandidateSet, false); 8231 8232 // Add operator candidates that are member functions. 8233 AddMemberOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 8234 8235 // Add candidates from ADL. 8236 AddArgumentDependentLookupCandidates(OpName, /*Operator*/ true, 8237 Args, 2, 8238 /*ExplicitTemplateArgs*/ 0, 8239 CandidateSet); 8240 8241 // Add builtin operator candidates. 8242 AddBuiltinOperatorCandidates(Op, OpLoc, Args, 2, CandidateSet); 8243 8244 // Perform overload resolution. 8245 OverloadCandidateSet::iterator Best; 8246 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 8247 case OR_Success: { 8248 // We found a built-in operator or an overloaded operator. 8249 FunctionDecl *FnDecl = Best->Function; 8250 8251 if (FnDecl) { 8252 // We matched an overloaded operator. Build a call to that 8253 // operator. 8254 8255 MarkDeclarationReferenced(OpLoc, FnDecl); 8256 8257 // Convert the arguments. 8258 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(FnDecl)) { 8259 // Best->Access is only meaningful for class members. 8260 CheckMemberOperatorAccess(OpLoc, Args[0], Args[1], Best->FoundDecl); 8261 8262 ExprResult Arg1 = 8263 PerformCopyInitialization( 8264 InitializedEntity::InitializeParameter(Context, 8265 FnDecl->getParamDecl(0)), 8266 SourceLocation(), Owned(Args[1])); 8267 if (Arg1.isInvalid()) 8268 return ExprError(); 8269 8270 ExprResult Arg0 = 8271 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 8272 Best->FoundDecl, Method); 8273 if (Arg0.isInvalid()) 8274 return ExprError(); 8275 Args[0] = Arg0.takeAs<Expr>(); 8276 Args[1] = RHS = Arg1.takeAs<Expr>(); 8277 } else { 8278 // Convert the arguments. 8279 ExprResult Arg0 = PerformCopyInitialization( 8280 InitializedEntity::InitializeParameter(Context, 8281 FnDecl->getParamDecl(0)), 8282 SourceLocation(), Owned(Args[0])); 8283 if (Arg0.isInvalid()) 8284 return ExprError(); 8285 8286 ExprResult Arg1 = 8287 PerformCopyInitialization( 8288 InitializedEntity::InitializeParameter(Context, 8289 FnDecl->getParamDecl(1)), 8290 SourceLocation(), Owned(Args[1])); 8291 if (Arg1.isInvalid()) 8292 return ExprError(); 8293 Args[0] = LHS = Arg0.takeAs<Expr>(); 8294 Args[1] = RHS = Arg1.takeAs<Expr>(); 8295 } 8296 8297 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 8298 8299 // Determine the result type. 8300 QualType ResultTy = FnDecl->getResultType(); 8301 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8302 ResultTy = ResultTy.getNonLValueExprType(Context); 8303 8304 // Build the actual expression node. 8305 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, OpLoc); 8306 if (FnExpr.isInvalid()) 8307 return ExprError(); 8308 8309 CXXOperatorCallExpr *TheCall = 8310 new (Context) CXXOperatorCallExpr(Context, Op, FnExpr.take(), 8311 Args, 2, ResultTy, VK, OpLoc); 8312 8313 if (CheckCallReturnType(FnDecl->getResultType(), OpLoc, TheCall, 8314 FnDecl)) 8315 return ExprError(); 8316 8317 return MaybeBindToTemporary(TheCall); 8318 } else { 8319 // We matched a built-in operator. Convert the arguments, then 8320 // break out so that we will build the appropriate built-in 8321 // operator node. 8322 ExprResult ArgsRes0 = 8323 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 8324 Best->Conversions[0], AA_Passing); 8325 if (ArgsRes0.isInvalid()) 8326 return ExprError(); 8327 Args[0] = ArgsRes0.take(); 8328 8329 ExprResult ArgsRes1 = 8330 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 8331 Best->Conversions[1], AA_Passing); 8332 if (ArgsRes1.isInvalid()) 8333 return ExprError(); 8334 Args[1] = ArgsRes1.take(); 8335 break; 8336 } 8337 } 8338 8339 case OR_No_Viable_Function: { 8340 // C++ [over.match.oper]p9: 8341 // If the operator is the operator , [...] and there are no 8342 // viable functions, then the operator is assumed to be the 8343 // built-in operator and interpreted according to clause 5. 8344 if (Opc == BO_Comma) 8345 break; 8346 8347 // For class as left operand for assignment or compound assigment 8348 // operator do not fall through to handling in built-in, but report that 8349 // no overloaded assignment operator found 8350 ExprResult Result = ExprError(); 8351 if (Args[0]->getType()->isRecordType() && 8352 Opc >= BO_Assign && Opc <= BO_OrAssign) { 8353 Diag(OpLoc, diag::err_ovl_no_viable_oper) 8354 << BinaryOperator::getOpcodeStr(Opc) 8355 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8356 } else { 8357 // No viable function; try to create a built-in operation, which will 8358 // produce an error. Then, show the non-viable candidates. 8359 Result = CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8360 } 8361 assert(Result.isInvalid() && 8362 "C++ binary operator overloading is missing candidates!"); 8363 if (Result.isInvalid()) 8364 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8365 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8366 return move(Result); 8367 } 8368 8369 case OR_Ambiguous: 8370 Diag(OpLoc, diag::err_ovl_ambiguous_oper_binary) 8371 << BinaryOperator::getOpcodeStr(Opc) 8372 << Args[0]->getType() << Args[1]->getType() 8373 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8374 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 8375 BinaryOperator::getOpcodeStr(Opc), OpLoc); 8376 return ExprError(); 8377 8378 case OR_Deleted: 8379 Diag(OpLoc, diag::err_ovl_deleted_oper) 8380 << Best->Function->isDeleted() 8381 << BinaryOperator::getOpcodeStr(Opc) 8382 << getDeletedOrUnavailableSuffix(Best->Function) 8383 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8384 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2); 8385 return ExprError(); 8386 } 8387 8388 // We matched a built-in operator; build it. 8389 return CreateBuiltinBinOp(OpLoc, Opc, Args[0], Args[1]); 8390} 8391 8392ExprResult 8393Sema::CreateOverloadedArraySubscriptExpr(SourceLocation LLoc, 8394 SourceLocation RLoc, 8395 Expr *Base, Expr *Idx) { 8396 Expr *Args[2] = { Base, Idx }; 8397 DeclarationName OpName = 8398 Context.DeclarationNames.getCXXOperatorName(OO_Subscript); 8399 8400 // If either side is type-dependent, create an appropriate dependent 8401 // expression. 8402 if (Args[0]->isTypeDependent() || Args[1]->isTypeDependent()) { 8403 8404 CXXRecordDecl *NamingClass = 0; // because lookup ignores member operators 8405 // CHECKME: no 'operator' keyword? 8406 DeclarationNameInfo OpNameInfo(OpName, LLoc); 8407 OpNameInfo.setCXXOperatorNameRange(SourceRange(LLoc, RLoc)); 8408 UnresolvedLookupExpr *Fn 8409 = UnresolvedLookupExpr::Create(Context, NamingClass, 8410 NestedNameSpecifierLoc(), OpNameInfo, 8411 /*ADL*/ true, /*Overloaded*/ false, 8412 UnresolvedSetIterator(), 8413 UnresolvedSetIterator()); 8414 // Can't add any actual overloads yet 8415 8416 return Owned(new (Context) CXXOperatorCallExpr(Context, OO_Subscript, Fn, 8417 Args, 2, 8418 Context.DependentTy, 8419 VK_RValue, 8420 RLoc)); 8421 } 8422 8423 if (Args[0]->getObjectKind() == OK_ObjCProperty) { 8424 ExprResult Result = ConvertPropertyForRValue(Args[0]); 8425 if (Result.isInvalid()) 8426 return ExprError(); 8427 Args[0] = Result.take(); 8428 } 8429 if (Args[1]->getObjectKind() == OK_ObjCProperty) { 8430 ExprResult Result = ConvertPropertyForRValue(Args[1]); 8431 if (Result.isInvalid()) 8432 return ExprError(); 8433 Args[1] = Result.take(); 8434 } 8435 8436 // Build an empty overload set. 8437 OverloadCandidateSet CandidateSet(LLoc); 8438 8439 // Subscript can only be overloaded as a member function. 8440 8441 // Add operator candidates that are member functions. 8442 AddMemberOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 8443 8444 // Add builtin operator candidates. 8445 AddBuiltinOperatorCandidates(OO_Subscript, LLoc, Args, 2, CandidateSet); 8446 8447 // Perform overload resolution. 8448 OverloadCandidateSet::iterator Best; 8449 switch (CandidateSet.BestViableFunction(*this, LLoc, Best)) { 8450 case OR_Success: { 8451 // We found a built-in operator or an overloaded operator. 8452 FunctionDecl *FnDecl = Best->Function; 8453 8454 if (FnDecl) { 8455 // We matched an overloaded operator. Build a call to that 8456 // operator. 8457 8458 MarkDeclarationReferenced(LLoc, FnDecl); 8459 8460 CheckMemberOperatorAccess(LLoc, Args[0], Args[1], Best->FoundDecl); 8461 DiagnoseUseOfDecl(Best->FoundDecl, LLoc); 8462 8463 // Convert the arguments. 8464 CXXMethodDecl *Method = cast<CXXMethodDecl>(FnDecl); 8465 ExprResult Arg0 = 8466 PerformObjectArgumentInitialization(Args[0], /*Qualifier=*/0, 8467 Best->FoundDecl, Method); 8468 if (Arg0.isInvalid()) 8469 return ExprError(); 8470 Args[0] = Arg0.take(); 8471 8472 // Convert the arguments. 8473 ExprResult InputInit 8474 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 8475 Context, 8476 FnDecl->getParamDecl(0)), 8477 SourceLocation(), 8478 Owned(Args[1])); 8479 if (InputInit.isInvalid()) 8480 return ExprError(); 8481 8482 Args[1] = InputInit.takeAs<Expr>(); 8483 8484 // Determine the result type 8485 QualType ResultTy = FnDecl->getResultType(); 8486 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8487 ResultTy = ResultTy.getNonLValueExprType(Context); 8488 8489 // Build the actual expression node. 8490 ExprResult FnExpr = CreateFunctionRefExpr(*this, FnDecl, LLoc); 8491 if (FnExpr.isInvalid()) 8492 return ExprError(); 8493 8494 CXXOperatorCallExpr *TheCall = 8495 new (Context) CXXOperatorCallExpr(Context, OO_Subscript, 8496 FnExpr.take(), Args, 2, 8497 ResultTy, VK, RLoc); 8498 8499 if (CheckCallReturnType(FnDecl->getResultType(), LLoc, TheCall, 8500 FnDecl)) 8501 return ExprError(); 8502 8503 return MaybeBindToTemporary(TheCall); 8504 } else { 8505 // We matched a built-in operator. Convert the arguments, then 8506 // break out so that we will build the appropriate built-in 8507 // operator node. 8508 ExprResult ArgsRes0 = 8509 PerformImplicitConversion(Args[0], Best->BuiltinTypes.ParamTypes[0], 8510 Best->Conversions[0], AA_Passing); 8511 if (ArgsRes0.isInvalid()) 8512 return ExprError(); 8513 Args[0] = ArgsRes0.take(); 8514 8515 ExprResult ArgsRes1 = 8516 PerformImplicitConversion(Args[1], Best->BuiltinTypes.ParamTypes[1], 8517 Best->Conversions[1], AA_Passing); 8518 if (ArgsRes1.isInvalid()) 8519 return ExprError(); 8520 Args[1] = ArgsRes1.take(); 8521 8522 break; 8523 } 8524 } 8525 8526 case OR_No_Viable_Function: { 8527 if (CandidateSet.empty()) 8528 Diag(LLoc, diag::err_ovl_no_oper) 8529 << Args[0]->getType() << /*subscript*/ 0 8530 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8531 else 8532 Diag(LLoc, diag::err_ovl_no_viable_subscript) 8533 << Args[0]->getType() 8534 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8535 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8536 "[]", LLoc); 8537 return ExprError(); 8538 } 8539 8540 case OR_Ambiguous: 8541 Diag(LLoc, diag::err_ovl_ambiguous_oper_binary) 8542 << "[]" 8543 << Args[0]->getType() << Args[1]->getType() 8544 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8545 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, 2, 8546 "[]", LLoc); 8547 return ExprError(); 8548 8549 case OR_Deleted: 8550 Diag(LLoc, diag::err_ovl_deleted_oper) 8551 << Best->Function->isDeleted() << "[]" 8552 << getDeletedOrUnavailableSuffix(Best->Function) 8553 << Args[0]->getSourceRange() << Args[1]->getSourceRange(); 8554 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, 2, 8555 "[]", LLoc); 8556 return ExprError(); 8557 } 8558 8559 // We matched a built-in operator; build it. 8560 return CreateBuiltinArraySubscriptExpr(Args[0], LLoc, Args[1], RLoc); 8561} 8562 8563/// BuildCallToMemberFunction - Build a call to a member 8564/// function. MemExpr is the expression that refers to the member 8565/// function (and includes the object parameter), Args/NumArgs are the 8566/// arguments to the function call (not including the object 8567/// parameter). The caller needs to validate that the member 8568/// expression refers to a non-static member function or an overloaded 8569/// member function. 8570ExprResult 8571Sema::BuildCallToMemberFunction(Scope *S, Expr *MemExprE, 8572 SourceLocation LParenLoc, Expr **Args, 8573 unsigned NumArgs, SourceLocation RParenLoc) { 8574 assert(MemExprE->getType() == Context.BoundMemberTy || 8575 MemExprE->getType() == Context.OverloadTy); 8576 8577 // Dig out the member expression. This holds both the object 8578 // argument and the member function we're referring to. 8579 Expr *NakedMemExpr = MemExprE->IgnoreParens(); 8580 8581 // Determine whether this is a call to a pointer-to-member function. 8582 if (BinaryOperator *op = dyn_cast<BinaryOperator>(NakedMemExpr)) { 8583 assert(op->getType() == Context.BoundMemberTy); 8584 assert(op->getOpcode() == BO_PtrMemD || op->getOpcode() == BO_PtrMemI); 8585 8586 QualType fnType = 8587 op->getRHS()->getType()->castAs<MemberPointerType>()->getPointeeType(); 8588 8589 const FunctionProtoType *proto = fnType->castAs<FunctionProtoType>(); 8590 QualType resultType = proto->getCallResultType(Context); 8591 ExprValueKind valueKind = Expr::getValueKindForType(proto->getResultType()); 8592 8593 // Check that the object type isn't more qualified than the 8594 // member function we're calling. 8595 Qualifiers funcQuals = Qualifiers::fromCVRMask(proto->getTypeQuals()); 8596 8597 QualType objectType = op->getLHS()->getType(); 8598 if (op->getOpcode() == BO_PtrMemI) 8599 objectType = objectType->castAs<PointerType>()->getPointeeType(); 8600 Qualifiers objectQuals = objectType.getQualifiers(); 8601 8602 Qualifiers difference = objectQuals - funcQuals; 8603 difference.removeObjCGCAttr(); 8604 difference.removeAddressSpace(); 8605 if (difference) { 8606 std::string qualsString = difference.getAsString(); 8607 Diag(LParenLoc, diag::err_pointer_to_member_call_drops_quals) 8608 << fnType.getUnqualifiedType() 8609 << qualsString 8610 << (qualsString.find(' ') == std::string::npos ? 1 : 2); 8611 } 8612 8613 CXXMemberCallExpr *call 8614 = new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 8615 resultType, valueKind, RParenLoc); 8616 8617 if (CheckCallReturnType(proto->getResultType(), 8618 op->getRHS()->getSourceRange().getBegin(), 8619 call, 0)) 8620 return ExprError(); 8621 8622 if (ConvertArgumentsForCall(call, op, 0, proto, Args, NumArgs, RParenLoc)) 8623 return ExprError(); 8624 8625 return MaybeBindToTemporary(call); 8626 } 8627 8628 MemberExpr *MemExpr; 8629 CXXMethodDecl *Method = 0; 8630 DeclAccessPair FoundDecl = DeclAccessPair::make(0, AS_public); 8631 NestedNameSpecifier *Qualifier = 0; 8632 if (isa<MemberExpr>(NakedMemExpr)) { 8633 MemExpr = cast<MemberExpr>(NakedMemExpr); 8634 Method = cast<CXXMethodDecl>(MemExpr->getMemberDecl()); 8635 FoundDecl = MemExpr->getFoundDecl(); 8636 Qualifier = MemExpr->getQualifier(); 8637 } else { 8638 UnresolvedMemberExpr *UnresExpr = cast<UnresolvedMemberExpr>(NakedMemExpr); 8639 Qualifier = UnresExpr->getQualifier(); 8640 8641 QualType ObjectType = UnresExpr->getBaseType(); 8642 Expr::Classification ObjectClassification 8643 = UnresExpr->isArrow()? Expr::Classification::makeSimpleLValue() 8644 : UnresExpr->getBase()->Classify(Context); 8645 8646 // Add overload candidates 8647 OverloadCandidateSet CandidateSet(UnresExpr->getMemberLoc()); 8648 8649 // FIXME: avoid copy. 8650 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 8651 if (UnresExpr->hasExplicitTemplateArgs()) { 8652 UnresExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 8653 TemplateArgs = &TemplateArgsBuffer; 8654 } 8655 8656 for (UnresolvedMemberExpr::decls_iterator I = UnresExpr->decls_begin(), 8657 E = UnresExpr->decls_end(); I != E; ++I) { 8658 8659 NamedDecl *Func = *I; 8660 CXXRecordDecl *ActingDC = cast<CXXRecordDecl>(Func->getDeclContext()); 8661 if (isa<UsingShadowDecl>(Func)) 8662 Func = cast<UsingShadowDecl>(Func)->getTargetDecl(); 8663 8664 8665 // Microsoft supports direct constructor calls. 8666 if (getLangOptions().Microsoft && isa<CXXConstructorDecl>(Func)) { 8667 AddOverloadCandidate(cast<CXXConstructorDecl>(Func), I.getPair(), Args, NumArgs, 8668 CandidateSet); 8669 } else if ((Method = dyn_cast<CXXMethodDecl>(Func))) { 8670 // If explicit template arguments were provided, we can't call a 8671 // non-template member function. 8672 if (TemplateArgs) 8673 continue; 8674 8675 AddMethodCandidate(Method, I.getPair(), ActingDC, ObjectType, 8676 ObjectClassification, 8677 Args, NumArgs, CandidateSet, 8678 /*SuppressUserConversions=*/false); 8679 } else { 8680 AddMethodTemplateCandidate(cast<FunctionTemplateDecl>(Func), 8681 I.getPair(), ActingDC, TemplateArgs, 8682 ObjectType, ObjectClassification, 8683 Args, NumArgs, CandidateSet, 8684 /*SuppressUsedConversions=*/false); 8685 } 8686 } 8687 8688 DeclarationName DeclName = UnresExpr->getMemberName(); 8689 8690 OverloadCandidateSet::iterator Best; 8691 switch (CandidateSet.BestViableFunction(*this, UnresExpr->getLocStart(), 8692 Best)) { 8693 case OR_Success: 8694 Method = cast<CXXMethodDecl>(Best->Function); 8695 MarkDeclarationReferenced(UnresExpr->getMemberLoc(), Method); 8696 FoundDecl = Best->FoundDecl; 8697 CheckUnresolvedMemberAccess(UnresExpr, Best->FoundDecl); 8698 DiagnoseUseOfDecl(Best->FoundDecl, UnresExpr->getNameLoc()); 8699 break; 8700 8701 case OR_No_Viable_Function: 8702 Diag(UnresExpr->getMemberLoc(), 8703 diag::err_ovl_no_viable_member_function_in_call) 8704 << DeclName << MemExprE->getSourceRange(); 8705 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8706 // FIXME: Leaking incoming expressions! 8707 return ExprError(); 8708 8709 case OR_Ambiguous: 8710 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_ambiguous_member_call) 8711 << DeclName << MemExprE->getSourceRange(); 8712 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8713 // FIXME: Leaking incoming expressions! 8714 return ExprError(); 8715 8716 case OR_Deleted: 8717 Diag(UnresExpr->getMemberLoc(), diag::err_ovl_deleted_member_call) 8718 << Best->Function->isDeleted() 8719 << DeclName 8720 << getDeletedOrUnavailableSuffix(Best->Function) 8721 << MemExprE->getSourceRange(); 8722 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8723 // FIXME: Leaking incoming expressions! 8724 return ExprError(); 8725 } 8726 8727 MemExprE = FixOverloadedFunctionReference(MemExprE, FoundDecl, Method); 8728 8729 // If overload resolution picked a static member, build a 8730 // non-member call based on that function. 8731 if (Method->isStatic()) { 8732 return BuildResolvedCallExpr(MemExprE, Method, LParenLoc, 8733 Args, NumArgs, RParenLoc); 8734 } 8735 8736 MemExpr = cast<MemberExpr>(MemExprE->IgnoreParens()); 8737 } 8738 8739 QualType ResultType = Method->getResultType(); 8740 ExprValueKind VK = Expr::getValueKindForType(ResultType); 8741 ResultType = ResultType.getNonLValueExprType(Context); 8742 8743 assert(Method && "Member call to something that isn't a method?"); 8744 CXXMemberCallExpr *TheCall = 8745 new (Context) CXXMemberCallExpr(Context, MemExprE, Args, NumArgs, 8746 ResultType, VK, RParenLoc); 8747 8748 // Check for a valid return type. 8749 if (CheckCallReturnType(Method->getResultType(), MemExpr->getMemberLoc(), 8750 TheCall, Method)) 8751 return ExprError(); 8752 8753 // Convert the object argument (for a non-static member function call). 8754 // We only need to do this if there was actually an overload; otherwise 8755 // it was done at lookup. 8756 if (!Method->isStatic()) { 8757 ExprResult ObjectArg = 8758 PerformObjectArgumentInitialization(MemExpr->getBase(), Qualifier, 8759 FoundDecl, Method); 8760 if (ObjectArg.isInvalid()) 8761 return ExprError(); 8762 MemExpr->setBase(ObjectArg.take()); 8763 } 8764 8765 // Convert the rest of the arguments 8766 const FunctionProtoType *Proto = 8767 Method->getType()->getAs<FunctionProtoType>(); 8768 if (ConvertArgumentsForCall(TheCall, MemExpr, Method, Proto, Args, NumArgs, 8769 RParenLoc)) 8770 return ExprError(); 8771 8772 if (CheckFunctionCall(Method, TheCall)) 8773 return ExprError(); 8774 8775 return MaybeBindToTemporary(TheCall); 8776} 8777 8778/// BuildCallToObjectOfClassType - Build a call to an object of class 8779/// type (C++ [over.call.object]), which can end up invoking an 8780/// overloaded function call operator (@c operator()) or performing a 8781/// user-defined conversion on the object argument. 8782ExprResult 8783Sema::BuildCallToObjectOfClassType(Scope *S, Expr *Obj, 8784 SourceLocation LParenLoc, 8785 Expr **Args, unsigned NumArgs, 8786 SourceLocation RParenLoc) { 8787 ExprResult Object = Owned(Obj); 8788 if (Object.get()->getObjectKind() == OK_ObjCProperty) { 8789 Object = ConvertPropertyForRValue(Object.take()); 8790 if (Object.isInvalid()) 8791 return ExprError(); 8792 } 8793 8794 assert(Object.get()->getType()->isRecordType() && "Requires object type argument"); 8795 const RecordType *Record = Object.get()->getType()->getAs<RecordType>(); 8796 8797 // C++ [over.call.object]p1: 8798 // If the primary-expression E in the function call syntax 8799 // evaluates to a class object of type "cv T", then the set of 8800 // candidate functions includes at least the function call 8801 // operators of T. The function call operators of T are obtained by 8802 // ordinary lookup of the name operator() in the context of 8803 // (E).operator(). 8804 OverloadCandidateSet CandidateSet(LParenLoc); 8805 DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(OO_Call); 8806 8807 if (RequireCompleteType(LParenLoc, Object.get()->getType(), 8808 PDiag(diag::err_incomplete_object_call) 8809 << Object.get()->getSourceRange())) 8810 return true; 8811 8812 LookupResult R(*this, OpName, LParenLoc, LookupOrdinaryName); 8813 LookupQualifiedName(R, Record->getDecl()); 8814 R.suppressDiagnostics(); 8815 8816 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 8817 Oper != OperEnd; ++Oper) { 8818 AddMethodCandidate(Oper.getPair(), Object.get()->getType(), 8819 Object.get()->Classify(Context), Args, NumArgs, CandidateSet, 8820 /*SuppressUserConversions=*/ false); 8821 } 8822 8823 // C++ [over.call.object]p2: 8824 // In addition, for each conversion function declared in T of the 8825 // form 8826 // 8827 // operator conversion-type-id () cv-qualifier; 8828 // 8829 // where cv-qualifier is the same cv-qualification as, or a 8830 // greater cv-qualification than, cv, and where conversion-type-id 8831 // denotes the type "pointer to function of (P1,...,Pn) returning 8832 // R", or the type "reference to pointer to function of 8833 // (P1,...,Pn) returning R", or the type "reference to function 8834 // of (P1,...,Pn) returning R", a surrogate call function [...] 8835 // is also considered as a candidate function. Similarly, 8836 // surrogate call functions are added to the set of candidate 8837 // functions for each conversion function declared in an 8838 // accessible base class provided the function is not hidden 8839 // within T by another intervening declaration. 8840 const UnresolvedSetImpl *Conversions 8841 = cast<CXXRecordDecl>(Record->getDecl())->getVisibleConversionFunctions(); 8842 for (UnresolvedSetImpl::iterator I = Conversions->begin(), 8843 E = Conversions->end(); I != E; ++I) { 8844 NamedDecl *D = *I; 8845 CXXRecordDecl *ActingContext = cast<CXXRecordDecl>(D->getDeclContext()); 8846 if (isa<UsingShadowDecl>(D)) 8847 D = cast<UsingShadowDecl>(D)->getTargetDecl(); 8848 8849 // Skip over templated conversion functions; they aren't 8850 // surrogates. 8851 if (isa<FunctionTemplateDecl>(D)) 8852 continue; 8853 8854 CXXConversionDecl *Conv = cast<CXXConversionDecl>(D); 8855 8856 // Strip the reference type (if any) and then the pointer type (if 8857 // any) to get down to what might be a function type. 8858 QualType ConvType = Conv->getConversionType().getNonReferenceType(); 8859 if (const PointerType *ConvPtrType = ConvType->getAs<PointerType>()) 8860 ConvType = ConvPtrType->getPointeeType(); 8861 8862 if (const FunctionProtoType *Proto = ConvType->getAs<FunctionProtoType>()) 8863 AddSurrogateCandidate(Conv, I.getPair(), ActingContext, Proto, 8864 Object.get(), Args, NumArgs, CandidateSet); 8865 } 8866 8867 // Perform overload resolution. 8868 OverloadCandidateSet::iterator Best; 8869 switch (CandidateSet.BestViableFunction(*this, Object.get()->getLocStart(), 8870 Best)) { 8871 case OR_Success: 8872 // Overload resolution succeeded; we'll build the appropriate call 8873 // below. 8874 break; 8875 8876 case OR_No_Viable_Function: 8877 if (CandidateSet.empty()) 8878 Diag(Object.get()->getSourceRange().getBegin(), diag::err_ovl_no_oper) 8879 << Object.get()->getType() << /*call*/ 1 8880 << Object.get()->getSourceRange(); 8881 else 8882 Diag(Object.get()->getSourceRange().getBegin(), 8883 diag::err_ovl_no_viable_object_call) 8884 << Object.get()->getType() << Object.get()->getSourceRange(); 8885 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8886 break; 8887 8888 case OR_Ambiguous: 8889 Diag(Object.get()->getSourceRange().getBegin(), 8890 diag::err_ovl_ambiguous_object_call) 8891 << Object.get()->getType() << Object.get()->getSourceRange(); 8892 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, Args, NumArgs); 8893 break; 8894 8895 case OR_Deleted: 8896 Diag(Object.get()->getSourceRange().getBegin(), 8897 diag::err_ovl_deleted_object_call) 8898 << Best->Function->isDeleted() 8899 << Object.get()->getType() 8900 << getDeletedOrUnavailableSuffix(Best->Function) 8901 << Object.get()->getSourceRange(); 8902 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, Args, NumArgs); 8903 break; 8904 } 8905 8906 if (Best == CandidateSet.end()) 8907 return true; 8908 8909 if (Best->Function == 0) { 8910 // Since there is no function declaration, this is one of the 8911 // surrogate candidates. Dig out the conversion function. 8912 CXXConversionDecl *Conv 8913 = cast<CXXConversionDecl>( 8914 Best->Conversions[0].UserDefined.ConversionFunction); 8915 8916 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 8917 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 8918 8919 // We selected one of the surrogate functions that converts the 8920 // object parameter to a function pointer. Perform the conversion 8921 // on the object argument, then let ActOnCallExpr finish the job. 8922 8923 // Create an implicit member expr to refer to the conversion operator. 8924 // and then call it. 8925 ExprResult Call = BuildCXXMemberCallExpr(Object.get(), Best->FoundDecl, Conv); 8926 if (Call.isInvalid()) 8927 return ExprError(); 8928 8929 return ActOnCallExpr(S, Call.get(), LParenLoc, MultiExprArg(Args, NumArgs), 8930 RParenLoc); 8931 } 8932 8933 MarkDeclarationReferenced(LParenLoc, Best->Function); 8934 CheckMemberOperatorAccess(LParenLoc, Object.get(), 0, Best->FoundDecl); 8935 DiagnoseUseOfDecl(Best->FoundDecl, LParenLoc); 8936 8937 // We found an overloaded operator(). Build a CXXOperatorCallExpr 8938 // that calls this method, using Object for the implicit object 8939 // parameter and passing along the remaining arguments. 8940 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 8941 const FunctionProtoType *Proto = 8942 Method->getType()->getAs<FunctionProtoType>(); 8943 8944 unsigned NumArgsInProto = Proto->getNumArgs(); 8945 unsigned NumArgsToCheck = NumArgs; 8946 8947 // Build the full argument list for the method call (the 8948 // implicit object parameter is placed at the beginning of the 8949 // list). 8950 Expr **MethodArgs; 8951 if (NumArgs < NumArgsInProto) { 8952 NumArgsToCheck = NumArgsInProto; 8953 MethodArgs = new Expr*[NumArgsInProto + 1]; 8954 } else { 8955 MethodArgs = new Expr*[NumArgs + 1]; 8956 } 8957 MethodArgs[0] = Object.get(); 8958 for (unsigned ArgIdx = 0; ArgIdx < NumArgs; ++ArgIdx) 8959 MethodArgs[ArgIdx + 1] = Args[ArgIdx]; 8960 8961 ExprResult NewFn = CreateFunctionRefExpr(*this, Method); 8962 if (NewFn.isInvalid()) 8963 return true; 8964 8965 // Once we've built TheCall, all of the expressions are properly 8966 // owned. 8967 QualType ResultTy = Method->getResultType(); 8968 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 8969 ResultTy = ResultTy.getNonLValueExprType(Context); 8970 8971 CXXOperatorCallExpr *TheCall = 8972 new (Context) CXXOperatorCallExpr(Context, OO_Call, NewFn.take(), 8973 MethodArgs, NumArgs + 1, 8974 ResultTy, VK, RParenLoc); 8975 delete [] MethodArgs; 8976 8977 if (CheckCallReturnType(Method->getResultType(), LParenLoc, TheCall, 8978 Method)) 8979 return true; 8980 8981 // We may have default arguments. If so, we need to allocate more 8982 // slots in the call for them. 8983 if (NumArgs < NumArgsInProto) 8984 TheCall->setNumArgs(Context, NumArgsInProto + 1); 8985 else if (NumArgs > NumArgsInProto) 8986 NumArgsToCheck = NumArgsInProto; 8987 8988 bool IsError = false; 8989 8990 // Initialize the implicit object parameter. 8991 ExprResult ObjRes = 8992 PerformObjectArgumentInitialization(Object.get(), /*Qualifier=*/0, 8993 Best->FoundDecl, Method); 8994 if (ObjRes.isInvalid()) 8995 IsError = true; 8996 else 8997 Object = move(ObjRes); 8998 TheCall->setArg(0, Object.take()); 8999 9000 // Check the argument types. 9001 for (unsigned i = 0; i != NumArgsToCheck; i++) { 9002 Expr *Arg; 9003 if (i < NumArgs) { 9004 Arg = Args[i]; 9005 9006 // Pass the argument. 9007 9008 ExprResult InputInit 9009 = PerformCopyInitialization(InitializedEntity::InitializeParameter( 9010 Context, 9011 Method->getParamDecl(i)), 9012 SourceLocation(), Arg); 9013 9014 IsError |= InputInit.isInvalid(); 9015 Arg = InputInit.takeAs<Expr>(); 9016 } else { 9017 ExprResult DefArg 9018 = BuildCXXDefaultArgExpr(LParenLoc, Method, Method->getParamDecl(i)); 9019 if (DefArg.isInvalid()) { 9020 IsError = true; 9021 break; 9022 } 9023 9024 Arg = DefArg.takeAs<Expr>(); 9025 } 9026 9027 TheCall->setArg(i + 1, Arg); 9028 } 9029 9030 // If this is a variadic call, handle args passed through "...". 9031 if (Proto->isVariadic()) { 9032 // Promote the arguments (C99 6.5.2.2p7). 9033 for (unsigned i = NumArgsInProto; i != NumArgs; i++) { 9034 ExprResult Arg = DefaultVariadicArgumentPromotion(Args[i], VariadicMethod, 0); 9035 IsError |= Arg.isInvalid(); 9036 TheCall->setArg(i + 1, Arg.take()); 9037 } 9038 } 9039 9040 if (IsError) return true; 9041 9042 if (CheckFunctionCall(Method, TheCall)) 9043 return true; 9044 9045 return MaybeBindToTemporary(TheCall); 9046} 9047 9048/// BuildOverloadedArrowExpr - Build a call to an overloaded @c operator-> 9049/// (if one exists), where @c Base is an expression of class type and 9050/// @c Member is the name of the member we're trying to find. 9051ExprResult 9052Sema::BuildOverloadedArrowExpr(Scope *S, Expr *Base, SourceLocation OpLoc) { 9053 assert(Base->getType()->isRecordType() && 9054 "left-hand side must have class type"); 9055 9056 if (Base->getObjectKind() == OK_ObjCProperty) { 9057 ExprResult Result = ConvertPropertyForRValue(Base); 9058 if (Result.isInvalid()) 9059 return ExprError(); 9060 Base = Result.take(); 9061 } 9062 9063 SourceLocation Loc = Base->getExprLoc(); 9064 9065 // C++ [over.ref]p1: 9066 // 9067 // [...] An expression x->m is interpreted as (x.operator->())->m 9068 // for a class object x of type T if T::operator->() exists and if 9069 // the operator is selected as the best match function by the 9070 // overload resolution mechanism (13.3). 9071 DeclarationName OpName = 9072 Context.DeclarationNames.getCXXOperatorName(OO_Arrow); 9073 OverloadCandidateSet CandidateSet(Loc); 9074 const RecordType *BaseRecord = Base->getType()->getAs<RecordType>(); 9075 9076 if (RequireCompleteType(Loc, Base->getType(), 9077 PDiag(diag::err_typecheck_incomplete_tag) 9078 << Base->getSourceRange())) 9079 return ExprError(); 9080 9081 LookupResult R(*this, OpName, OpLoc, LookupOrdinaryName); 9082 LookupQualifiedName(R, BaseRecord->getDecl()); 9083 R.suppressDiagnostics(); 9084 9085 for (LookupResult::iterator Oper = R.begin(), OperEnd = R.end(); 9086 Oper != OperEnd; ++Oper) { 9087 AddMethodCandidate(Oper.getPair(), Base->getType(), Base->Classify(Context), 9088 0, 0, CandidateSet, /*SuppressUserConversions=*/false); 9089 } 9090 9091 // Perform overload resolution. 9092 OverloadCandidateSet::iterator Best; 9093 switch (CandidateSet.BestViableFunction(*this, OpLoc, Best)) { 9094 case OR_Success: 9095 // Overload resolution succeeded; we'll build the call below. 9096 break; 9097 9098 case OR_No_Viable_Function: 9099 if (CandidateSet.empty()) 9100 Diag(OpLoc, diag::err_typecheck_member_reference_arrow) 9101 << Base->getType() << Base->getSourceRange(); 9102 else 9103 Diag(OpLoc, diag::err_ovl_no_viable_oper) 9104 << "operator->" << Base->getSourceRange(); 9105 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 9106 return ExprError(); 9107 9108 case OR_Ambiguous: 9109 Diag(OpLoc, diag::err_ovl_ambiguous_oper_unary) 9110 << "->" << Base->getType() << Base->getSourceRange(); 9111 CandidateSet.NoteCandidates(*this, OCD_ViableCandidates, &Base, 1); 9112 return ExprError(); 9113 9114 case OR_Deleted: 9115 Diag(OpLoc, diag::err_ovl_deleted_oper) 9116 << Best->Function->isDeleted() 9117 << "->" 9118 << getDeletedOrUnavailableSuffix(Best->Function) 9119 << Base->getSourceRange(); 9120 CandidateSet.NoteCandidates(*this, OCD_AllCandidates, &Base, 1); 9121 return ExprError(); 9122 } 9123 9124 MarkDeclarationReferenced(OpLoc, Best->Function); 9125 CheckMemberOperatorAccess(OpLoc, Base, 0, Best->FoundDecl); 9126 DiagnoseUseOfDecl(Best->FoundDecl, OpLoc); 9127 9128 // Convert the object parameter. 9129 CXXMethodDecl *Method = cast<CXXMethodDecl>(Best->Function); 9130 ExprResult BaseResult = 9131 PerformObjectArgumentInitialization(Base, /*Qualifier=*/0, 9132 Best->FoundDecl, Method); 9133 if (BaseResult.isInvalid()) 9134 return ExprError(); 9135 Base = BaseResult.take(); 9136 9137 // Build the operator call. 9138 ExprResult FnExpr = CreateFunctionRefExpr(*this, Method); 9139 if (FnExpr.isInvalid()) 9140 return ExprError(); 9141 9142 QualType ResultTy = Method->getResultType(); 9143 ExprValueKind VK = Expr::getValueKindForType(ResultTy); 9144 ResultTy = ResultTy.getNonLValueExprType(Context); 9145 CXXOperatorCallExpr *TheCall = 9146 new (Context) CXXOperatorCallExpr(Context, OO_Arrow, FnExpr.take(), 9147 &Base, 1, ResultTy, VK, OpLoc); 9148 9149 if (CheckCallReturnType(Method->getResultType(), OpLoc, TheCall, 9150 Method)) 9151 return ExprError(); 9152 9153 return MaybeBindToTemporary(TheCall); 9154} 9155 9156/// FixOverloadedFunctionReference - E is an expression that refers to 9157/// a C++ overloaded function (possibly with some parentheses and 9158/// perhaps a '&' around it). We have resolved the overloaded function 9159/// to the function declaration Fn, so patch up the expression E to 9160/// refer (possibly indirectly) to Fn. Returns the new expr. 9161Expr *Sema::FixOverloadedFunctionReference(Expr *E, DeclAccessPair Found, 9162 FunctionDecl *Fn) { 9163 if (ParenExpr *PE = dyn_cast<ParenExpr>(E)) { 9164 Expr *SubExpr = FixOverloadedFunctionReference(PE->getSubExpr(), 9165 Found, Fn); 9166 if (SubExpr == PE->getSubExpr()) 9167 return PE; 9168 9169 return new (Context) ParenExpr(PE->getLParen(), PE->getRParen(), SubExpr); 9170 } 9171 9172 if (ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) { 9173 Expr *SubExpr = FixOverloadedFunctionReference(ICE->getSubExpr(), 9174 Found, Fn); 9175 assert(Context.hasSameType(ICE->getSubExpr()->getType(), 9176 SubExpr->getType()) && 9177 "Implicit cast type cannot be determined from overload"); 9178 assert(ICE->path_empty() && "fixing up hierarchy conversion?"); 9179 if (SubExpr == ICE->getSubExpr()) 9180 return ICE; 9181 9182 return ImplicitCastExpr::Create(Context, ICE->getType(), 9183 ICE->getCastKind(), 9184 SubExpr, 0, 9185 ICE->getValueKind()); 9186 } 9187 9188 if (UnaryOperator *UnOp = dyn_cast<UnaryOperator>(E)) { 9189 assert(UnOp->getOpcode() == UO_AddrOf && 9190 "Can only take the address of an overloaded function"); 9191 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) { 9192 if (Method->isStatic()) { 9193 // Do nothing: static member functions aren't any different 9194 // from non-member functions. 9195 } else { 9196 // Fix the sub expression, which really has to be an 9197 // UnresolvedLookupExpr holding an overloaded member function 9198 // or template. 9199 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 9200 Found, Fn); 9201 if (SubExpr == UnOp->getSubExpr()) 9202 return UnOp; 9203 9204 assert(isa<DeclRefExpr>(SubExpr) 9205 && "fixed to something other than a decl ref"); 9206 assert(cast<DeclRefExpr>(SubExpr)->getQualifier() 9207 && "fixed to a member ref with no nested name qualifier"); 9208 9209 // We have taken the address of a pointer to member 9210 // function. Perform the computation here so that we get the 9211 // appropriate pointer to member type. 9212 QualType ClassType 9213 = Context.getTypeDeclType(cast<RecordDecl>(Method->getDeclContext())); 9214 QualType MemPtrType 9215 = Context.getMemberPointerType(Fn->getType(), ClassType.getTypePtr()); 9216 9217 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, MemPtrType, 9218 VK_RValue, OK_Ordinary, 9219 UnOp->getOperatorLoc()); 9220 } 9221 } 9222 Expr *SubExpr = FixOverloadedFunctionReference(UnOp->getSubExpr(), 9223 Found, Fn); 9224 if (SubExpr == UnOp->getSubExpr()) 9225 return UnOp; 9226 9227 return new (Context) UnaryOperator(SubExpr, UO_AddrOf, 9228 Context.getPointerType(SubExpr->getType()), 9229 VK_RValue, OK_Ordinary, 9230 UnOp->getOperatorLoc()); 9231 } 9232 9233 if (UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(E)) { 9234 // FIXME: avoid copy. 9235 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9236 if (ULE->hasExplicitTemplateArgs()) { 9237 ULE->copyTemplateArgumentsInto(TemplateArgsBuffer); 9238 TemplateArgs = &TemplateArgsBuffer; 9239 } 9240 9241 return DeclRefExpr::Create(Context, 9242 ULE->getQualifierLoc(), 9243 Fn, 9244 ULE->getNameLoc(), 9245 Fn->getType(), 9246 VK_LValue, 9247 Found.getDecl(), 9248 TemplateArgs); 9249 } 9250 9251 if (UnresolvedMemberExpr *MemExpr = dyn_cast<UnresolvedMemberExpr>(E)) { 9252 // FIXME: avoid copy. 9253 TemplateArgumentListInfo TemplateArgsBuffer, *TemplateArgs = 0; 9254 if (MemExpr->hasExplicitTemplateArgs()) { 9255 MemExpr->copyTemplateArgumentsInto(TemplateArgsBuffer); 9256 TemplateArgs = &TemplateArgsBuffer; 9257 } 9258 9259 Expr *Base; 9260 9261 // If we're filling in a static method where we used to have an 9262 // implicit member access, rewrite to a simple decl ref. 9263 if (MemExpr->isImplicitAccess()) { 9264 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 9265 return DeclRefExpr::Create(Context, 9266 MemExpr->getQualifierLoc(), 9267 Fn, 9268 MemExpr->getMemberLoc(), 9269 Fn->getType(), 9270 VK_LValue, 9271 Found.getDecl(), 9272 TemplateArgs); 9273 } else { 9274 SourceLocation Loc = MemExpr->getMemberLoc(); 9275 if (MemExpr->getQualifier()) 9276 Loc = MemExpr->getQualifierLoc().getBeginLoc(); 9277 Base = new (Context) CXXThisExpr(Loc, 9278 MemExpr->getBaseType(), 9279 /*isImplicit=*/true); 9280 } 9281 } else 9282 Base = MemExpr->getBase(); 9283 9284 ExprValueKind valueKind; 9285 QualType type; 9286 if (cast<CXXMethodDecl>(Fn)->isStatic()) { 9287 valueKind = VK_LValue; 9288 type = Fn->getType(); 9289 } else { 9290 valueKind = VK_RValue; 9291 type = Context.BoundMemberTy; 9292 } 9293 9294 return MemberExpr::Create(Context, Base, 9295 MemExpr->isArrow(), 9296 MemExpr->getQualifierLoc(), 9297 Fn, 9298 Found, 9299 MemExpr->getMemberNameInfo(), 9300 TemplateArgs, 9301 type, valueKind, OK_Ordinary); 9302 } 9303 9304 llvm_unreachable("Invalid reference to overloaded function"); 9305 return E; 9306} 9307 9308ExprResult Sema::FixOverloadedFunctionReference(ExprResult E, 9309 DeclAccessPair Found, 9310 FunctionDecl *Fn) { 9311 return Owned(FixOverloadedFunctionReference((Expr *)E.get(), Found, Fn)); 9312} 9313 9314} // end namespace clang 9315